handler = handlers.at(i); int index = map->IndexInCodeCache(*name, *handler); if (index >= 0) { map->RemoveFromCodeCache(*name, *handler, index); return; } } } bool IC::IsNameCompatibleWithMonomorphicPrototypeFailure(Handle name) { if (target()->is_keyed_stub()) { // Determine whether the failure is due to a name failure. if (!name->IsName()) return false; Name* stub_name = target()->FindFirstName(); if (*name != stub_name) return false; } return true; } void IC::UpdateState(Handle receiver, Handle name) { if (!name->IsString()) return; if (state() != MONOMORPHIC) { if (state() == POLYMORPHIC && receiver->IsHeapObject()) { TryRemoveInvalidHandlers( handle(Handle::cast(receiver)->map()), Handle::cast(name)); } return; } if (receiver->IsUndefined() || receiver->IsNull()) return; // Remove the target from the code cache if it became invalid // because of changes in the prototype chain to avoid hitting it // again. if (TryRemoveInvalidPrototypeDependentStub( receiver, Handle::cast(name)) && TryMarkMonomorphicPrototypeFailure(name)) { return; } // The builtins object is special. It only changes when JavaScript // builtins are loaded lazily. It is important to keep inline // caches for the builtins object monomorphic. Therefore, if we get // an inline cache miss for the builtins object after lazily loading // JavaScript builtins, we return uninitialized as the state to // force the inline cache back to monomorphic state. if (receiver->IsJSBuiltinsObject()) state_ = UNINITIALIZED; } MaybeHandle IC::TypeError(const char* type, Handle object, Handle key) { HandleScope scope(isolate()); Handle args[2] = { key, object }; Handle error = isolate()->factory()->NewTypeError( type, HandleVector(args, 2)); return isolate()->Throw(error); } MaybeHandle IC::ReferenceError(const char* type, Handle name) { HandleScope scope(isolate()); Handle error = isolate()->factory()->NewReferenceError( type, HandleVector(&name, 1)); return isolate()->Throw(error); } static int ComputeTypeInfoCountDelta(IC::State old_state, IC::State new_state) { bool was_uninitialized = old_state == UNINITIALIZED || old_state == PREMONOMORPHIC; bool is_uninitialized = new_state == UNINITIALIZED || new_state == PREMONOMORPHIC; return (was_uninitialized && !is_uninitialized) ? 1 : (!was_uninitialized && is_uninitialized) ? -1 : 0; } void IC::PostPatching(Address address, Code* target, Code* old_target) { Isolate* isolate = target->GetHeap()->isolate(); Code* host = isolate-> inner_pointer_to_code_cache()->GetCacheEntry(address)->code; if (host->kind() != Code::FUNCTION) return; if (FLAG_type_info_threshold > 0 && old_target->is_inline_cache_stub() && target->is_inline_cache_stub()) { int delta = ComputeTypeInfoCountDelta(old_target->ic_state(), target->ic_state()); // Call ICs don't have interesting state changes from this point // of view. ASSERT(target->kind() != Code::CALL_IC || delta == 0); // Not all Code objects have TypeFeedbackInfo. if (host->type_feedback_info()->IsTypeFeedbackInfo() && delta != 0) { TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info()); info->change_ic_with_type_info_count(delta); } } if (host->type_feedback_info()->IsTypeFeedbackInfo()) { TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info()); info->change_own_type_change_checksum(); } host->set_profiler_ticks(0); isolate->runtime_profiler()->NotifyICChanged(); // TODO(2029): When an optimized function is patched, it would // be nice to propagate the corresponding type information to its // unoptimized version for the benefit of later inlining. } void IC::RegisterWeakMapDependency(Handle stub) { if (FLAG_collect_maps && FLAG_weak_embedded_maps_in_ic && stub->CanBeWeakStub()) { ASSERT(!stub->is_weak_stub()); MapHandleList maps; stub->FindAllMaps(&maps); if (maps.length() == 1 && stub->IsWeakObjectInIC(*maps.at(0))) { Map::AddDependentIC(maps.at(0), stub); stub->mark_as_weak_stub(); if (FLAG_enable_ool_constant_pool) { stub->constant_pool()->set_weak_object_state( ConstantPoolArray::WEAK_OBJECTS_IN_IC); } } } } void IC::InvalidateMaps(Code* stub) { ASSERT(stub->is_weak_stub()); stub->mark_as_invalidated_weak_stub(); Isolate* isolate = stub->GetIsolate(); Heap* heap = isolate->heap(); Object* undefined = heap->undefined_value(); int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT); for (RelocIterator it(stub, mode_mask); !it.done(); it.next()) { RelocInfo::Mode mode = it.rinfo()->rmode(); if (mode == RelocInfo::EMBEDDED_OBJECT && it.rinfo()->target_object()->IsMap()) { it.rinfo()->set_target_object(undefined, SKIP_WRITE_BARRIER); } } CPU::FlushICache(stub->instruction_start(), stub->instruction_size()); } void IC::Clear(Isolate* isolate, Address address, ConstantPoolArray* constant_pool) { Code* target = GetTargetAtAddress(address, constant_pool); // Don't clear debug break inline cache as it will remove the break point. if (target->is_debug_stub()) return; switch (target->kind()) { case Code::LOAD_IC: return LoadIC::Clear(isolate, address, target, constant_pool); case Code::KEYED_LOAD_IC: return KeyedLoadIC::Clear(isolate, address, target, constant_pool); case Code::STORE_IC: return StoreIC::Clear(isolate, address, target, constant_pool); case Code::KEYED_STORE_IC: return KeyedStoreIC::Clear(isolate, address, target, constant_pool); case Code::CALL_IC: return CallIC::Clear(isolate, address, target, constant_pool); case Code::COMPARE_IC: return CompareIC::Clear(isolate, address, target, constant_pool); case Code::COMPARE_NIL_IC: return CompareNilIC::Clear(address, target, constant_pool); case Code::BINARY_OP_IC: case Code::TO_BOOLEAN_IC: // Clearing these is tricky and does not // make any performance difference. return; default: UNREACHABLE(); } } void KeyedLoadIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; // Make sure to also clear the map used in inline fast cases. If we // do not clear these maps, cached code can keep objects alive // through the embedded maps. SetTargetAtAddress(address, *pre_monomorphic_stub(isolate), constant_pool); } void CallIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { // Currently, CallIC doesn't have state changes. } void LoadIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; Code* code = target->GetIsolate()->stub_cache()->FindPreMonomorphicIC( Code::LOAD_IC, target->extra_ic_state()); SetTargetAtAddress(address, code, constant_pool); } void StoreIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; Code* code = target->GetIsolate()->stub_cache()->FindPreMonomorphicIC( Code::STORE_IC, target->extra_ic_state()); SetTargetAtAddress(address, code, constant_pool); } void KeyedStoreIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; SetTargetAtAddress(address, *pre_monomorphic_stub( isolate, StoreIC::GetStrictMode(target->extra_ic_state())), constant_pool); } void CompareIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { ASSERT(target->major_key() == CodeStub::CompareIC); CompareIC::State handler_state; Token::Value op; ICCompareStub::DecodeMinorKey(target->stub_info(), NULL, NULL, &handler_state, &op); // Only clear CompareICs that can retain objects. if (handler_state != KNOWN_OBJECT) return; SetTargetAtAddress(address, GetRawUninitialized(isolate, op), constant_pool); PatchInlinedSmiCode(address, DISABLE_INLINED_SMI_CHECK); } Handle KeyedLoadIC::megamorphic_stub() { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } Handle KeyedLoadIC::generic_stub() const { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } static bool MigrateDeprecated(Handle object) { if (!object->IsJSObject()) return false; Handle receiver = Handle::cast(object); if (!receiver->map()->is_deprecated()) return false; JSObject::MigrateInstance(Handle::cast(object)); return true; } MaybeHandle LoadIC::Load(Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && String::Equals(isolate()->factory()->prototype_string(), name) && Handle::cast(object)->should_have_prototype()) { Handle stub; if (state() == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state() == PREMONOMORPHIC) { FunctionPrototypeStub function_prototype_stub(isolate(), kind()); stub = function_prototype_stub.GetCode(); } else if (state() != MEGAMORPHIC) { ASSERT(state() != GENERIC); stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); } return Accessors::FunctionGetPrototype(Handle::cast(object)); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index; if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetElementOrCharAt(isolate(), object, index), Object); return result; } bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic; // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (use_ic) UpdateCaches(&lookup, object, name); // Get the property. LookupIterator it(object, name); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Object::GetProperty(&it), Object); // If the property is not present, check if we need to throw an exception. if ((lookup.IsInterceptor() || lookup.IsHandler()) && !it.IsFound() && IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } return result; } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } bool IC::UpdatePolymorphicIC(Handle type, Handle name, Handle code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub) { if (FLAG_collect_maps && FLAG_weak_embedded_maps_in_ic && stub->CanBeWeakStub()) { ASSERT(!stub->is_weak_stub()); MapHandleList maps; stub->FindAllMaps(&maps); if (maps.length() == 1 && stub->IsWeakObjectInIC(*maps.at(0))) { Map::AddDependentIC(maps.at(0), stub); stub->mark_as_weak_stub(); if (FLAG_enable_ool_constant_pool) { stub->constant_pool()->set_weak_object_state( ConstantPoolArray::WEAK_OBJECTS_IN_IC); } } } } void IC::InvalidateMaps(Code* stub) { ASSERT(stub->is_weak_stub()); stub->mark_as_invalidated_weak_stub(); Isolate* isolate = stub->GetIsolate(); Heap* heap = isolate->heap(); Object* undefined = heap->undefined_value(); int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT); for (RelocIterator it(stub, mode_mask); !it.done(); it.next()) { RelocInfo::Mode mode = it.rinfo()->rmode(); if (mode == RelocInfo::EMBEDDED_OBJECT && it.rinfo()->target_object()->IsMap()) { it.rinfo()->set_target_object(undefined, SKIP_WRITE_BARRIER); } } CPU::FlushICache(stub->instruction_start(), stub->instruction_size()); } void IC::Clear(Isolate* isolate, Address address, ConstantPoolArray* constant_pool) { Code* target = GetTargetAtAddress(address, constant_pool); // Don't clear debug break inline cache as it will remove the break point. if (target->is_debug_stub()) return; switch (target->kind()) { case Code::LOAD_IC: return LoadIC::Clear(isolate, address, target, constant_pool); case Code::KEYED_LOAD_IC: return KeyedLoadIC::Clear(isolate, address, target, constant_pool); case Code::STORE_IC: return StoreIC::Clear(isolate, address, target, constant_pool); case Code::KEYED_STORE_IC: return KeyedStoreIC::Clear(isolate, address, target, constant_pool); case Code::CALL_IC: return CallIC::Clear(isolate, address, target, constant_pool); case Code::COMPARE_IC: return CompareIC::Clear(isolate, address, target, constant_pool); case Code::COMPARE_NIL_IC: return CompareNilIC::Clear(address, target, constant_pool); case Code::BINARY_OP_IC: case Code::TO_BOOLEAN_IC: // Clearing these is tricky and does not // make any performance difference. return; default: UNREACHABLE(); } } void KeyedLoadIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; // Make sure to also clear the map used in inline fast cases. If we // do not clear these maps, cached code can keep objects alive // through the embedded maps. SetTargetAtAddress(address, *pre_monomorphic_stub(isolate), constant_pool); } void CallIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { // Currently, CallIC doesn't have state changes. } void LoadIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; Code* code = target->GetIsolate()->stub_cache()->FindPreMonomorphicIC( Code::LOAD_IC, target->extra_ic_state()); SetTargetAtAddress(address, code, constant_pool); } void StoreIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; Code* code = target->GetIsolate()->stub_cache()->FindPreMonomorphicIC( Code::STORE_IC, target->extra_ic_state()); SetTargetAtAddress(address, code, constant_pool); } void KeyedStoreIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { if (IsCleared(target)) return; SetTargetAtAddress(address, *pre_monomorphic_stub( isolate, StoreIC::GetStrictMode(target->extra_ic_state())), constant_pool); } void CompareIC::Clear(Isolate* isolate, Address address, Code* target, ConstantPoolArray* constant_pool) { ASSERT(target->major_key() == CodeStub::CompareIC); CompareIC::State handler_state; Token::Value op; ICCompareStub::DecodeMinorKey(target->stub_info(), NULL, NULL, &handler_state, &op); // Only clear CompareICs that can retain objects. if (handler_state != KNOWN_OBJECT) return; SetTargetAtAddress(address, GetRawUninitialized(isolate, op), constant_pool); PatchInlinedSmiCode(address, DISABLE_INLINED_SMI_CHECK); } Handle KeyedLoadIC::megamorphic_stub() { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } Handle KeyedLoadIC::generic_stub() const { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } static bool MigrateDeprecated(Handle object) { if (!object->IsJSObject()) return false; Handle receiver = Handle::cast(object); if (!receiver->map()->is_deprecated()) return false; JSObject::MigrateInstance(Handle::cast(object)); return true; } MaybeHandle LoadIC::Load(Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && String::Equals(isolate()->factory()->prototype_string(), name) && Handle::cast(object)->should_have_prototype()) { Handle stub; if (state() == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state() == PREMONOMORPHIC) { FunctionPrototypeStub function_prototype_stub(isolate(), kind()); stub = function_prototype_stub.GetCode(); } else if (state() != MEGAMORPHIC) { ASSERT(state() != GENERIC); stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); } return Accessors::FunctionGetPrototype(Handle::cast(object)); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index; if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetElementOrCharAt(isolate(), object, index), Object); return result; } bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic; // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (use_ic) UpdateCaches(&lookup, object, name); // Get the property. LookupIterator it(object, name); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Object::GetProperty(&it), Object); // If the property is not present, check if we need to throw an exception. if ((lookup.IsInterceptor() || lookup.IsHandler()) && !it.IsFound() && IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } return result; } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } bool IC::UpdatePolymorphicIC(Handle type, Handle name, Handle code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
KeyedLoadIC::megamorphic_stub() { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } Handle KeyedLoadIC::generic_stub() const { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } static bool MigrateDeprecated(Handle object) { if (!object->IsJSObject()) return false; Handle receiver = Handle::cast(object); if (!receiver->map()->is_deprecated()) return false; JSObject::MigrateInstance(Handle::cast(object)); return true; } MaybeHandle LoadIC::Load(Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && String::Equals(isolate()->factory()->prototype_string(), name) && Handle::cast(object)->should_have_prototype()) { Handle stub; if (state() == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state() == PREMONOMORPHIC) { FunctionPrototypeStub function_prototype_stub(isolate(), kind()); stub = function_prototype_stub.GetCode(); } else if (state() != MEGAMORPHIC) { ASSERT(state() != GENERIC); stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); } return Accessors::FunctionGetPrototype(Handle::cast(object)); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index; if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetElementOrCharAt(isolate(), object, index), Object); return result; } bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic; // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (use_ic) UpdateCaches(&lookup, object, name); // Get the property. LookupIterator it(object, name); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Object::GetProperty(&it), Object); // If the property is not present, check if we need to throw an exception. if ((lookup.IsInterceptor() || lookup.IsHandler()) && !it.IsFound() && IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } return result; } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } bool IC::UpdatePolymorphicIC(Handle type, Handle name, Handle code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
KeyedLoadIC::generic_stub() const { if (FLAG_compiled_keyed_generic_loads) { return KeyedLoadGenericElementStub(isolate()).GetCode(); } else { return isolate()->builtins()->KeyedLoadIC_Generic(); } } static bool MigrateDeprecated(Handle object) { if (!object->IsJSObject()) return false; Handle receiver = Handle::cast(object); if (!receiver->map()->is_deprecated()) return false; JSObject::MigrateInstance(Handle::cast(object)); return true; } MaybeHandle LoadIC::Load(Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && String::Equals(isolate()->factory()->prototype_string(), name) && Handle::cast(object)->should_have_prototype()) { Handle stub; if (state() == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state() == PREMONOMORPHIC) { FunctionPrototypeStub function_prototype_stub(isolate(), kind()); stub = function_prototype_stub.GetCode(); } else if (state() != MEGAMORPHIC) { ASSERT(state() != GENERIC); stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); } return Accessors::FunctionGetPrototype(Handle::cast(object)); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index; if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetElementOrCharAt(isolate(), object, index), Object); return result; } bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic; // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (use_ic) UpdateCaches(&lookup, object, name); // Get the property. LookupIterator it(object, name); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Object::GetProperty(&it), Object); // If the property is not present, check if we need to throw an exception. if ((lookup.IsInterceptor() || lookup.IsHandler()) && !it.IsFound() && IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } return result; } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } bool IC::UpdatePolymorphicIC(Handle type, Handle name, Handle code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub; if (state() == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state() == PREMONOMORPHIC) { FunctionPrototypeStub function_prototype_stub(isolate(), kind()); stub = function_prototype_stub.GetCode(); } else if (state() != MEGAMORPHIC) { ASSERT(state() != GENERIC); stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); } return Accessors::FunctionGetPrototype(Handle::cast(object)); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index; if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetElementOrCharAt(isolate(), object, index), Object); return result; } bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic; // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (use_ic) UpdateCaches(&lookup, object, name); // Get the property. LookupIterator it(object, name); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Object::GetProperty(&it), Object); // If the property is not present, check if we need to throw an exception. if ((lookup.IsInterceptor() || lookup.IsHandler()) && !it.IsFound() && IsUndeclaredGlobal(object)) { return ReferenceError("not_defined", name); } return result; } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } bool IC::UpdatePolymorphicIC(Handle type, Handle name, Handle code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code) { if (!code->is_handler()) return false; TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); int number_of_types = types.length(); int deprecated_types = 0; int handler_to_overwrite = -1; for (int i = 0; i < number_of_types; i++) { Handle current_type = types.at(i); if (current_type->IsClass() && current_type->AsClass()->Map()->is_deprecated()) { // Filter out deprecated maps to ensure their instances get migrated. ++deprecated_types; } else if (type->NowIs(current_type)) { // If the receiver type is already in the polymorphic IC, this indicates // there was a prototoype chain failure. In that case, just overwrite the // handler. handler_to_overwrite = i; } else if (handler_to_overwrite == -1 && current_type->IsClass() && type->IsClass() && IsTransitionOfMonomorphicTarget(*current_type->AsClass()->Map(), *type->AsClass()->Map())) { handler_to_overwrite = i; } } int number_of_valid_types = number_of_types - deprecated_types - (handler_to_overwrite != -1); if (number_of_valid_types >= 4) return false; if (number_of_types == 0) return false; if (!target()->FindHandlers(&handlers, types.length())) return false; number_of_valid_types++; if (handler_to_overwrite >= 0) { handlers.Set(handler_to_overwrite, code); if (!type->NowIs(types.at(handler_to_overwrite))) { types.Set(handler_to_overwrite, type); } } else { types.Add(type); handlers.Add(code); } Handle ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
ic = isolate()->stub_cache()->ComputePolymorphicIC( kind(), &types, &handlers, number_of_valid_types, name, extra_ic_state()); set_target(*ic); return true; } Handle IC::CurrentTypeOf(Handle object, Isolate* isolate) { return object->IsJSGlobalObject() ? HeapType::Constant(Handle::cast(object), isolate) : HeapType::NowOf(object, isolate); } Handle IC::TypeToMap(HeapType* type, Isolate* isolate) { if (type->Is(HeapType::Number())) return isolate->factory()->heap_number_map(); if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map(); if (type->IsConstant()) { return handle( Handle::cast(type->AsConstant()->Value())->map()); } ASSERT(type->IsClass()); return type->AsClass()->Map(); } template typename T::TypeHandle IC::MapToType(Handle map, typename T::Region* region) { if (map->instance_type() == HEAP_NUMBER_TYPE) { return T::Number(region); } else if (map->instance_type() == ODDBALL_TYPE) { // The only oddballs that can be recorded in ICs are booleans. return T::Boolean(region); } else { return T::Class(map, region); } } template Type* IC::MapToType(Handle map, Zone* zone); template Handle IC::MapToType(Handle map, Isolate* region); void IC::UpdateMonomorphicIC(Handle type, Handle handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
handler, Handle name) { if (!handler->is_handler()) return set_target(*handler); Handle ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
ic = isolate()->stub_cache()->ComputeMonomorphicIC( kind(), name, type, handler, extra_ic_state()); set_target(*ic); } void IC::CopyICToMegamorphicCache(Handle name) { TypeHandleList types; CodeHandleList handlers; TargetTypes(&types); if (!target()->FindHandlers(&handlers, types.length())) return; for (int i = 0; i < types.length(); i++) { UpdateMegamorphicCache(*types.at(i), *name, *handlers.at(i)); } } bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) { if (source_map == NULL) return true; if (target_map == NULL) return false; ElementsKind target_elements_kind = target_map->elements_kind(); bool more_general_transition = IsMoreGeneralElementsKindTransition( source_map->elements_kind(), target_elements_kind); Map* transitioned_map = more_general_transition ? source_map->LookupElementsTransitionMap(target_elements_kind) : NULL; return transitioned_map == target_map; } void IC::PatchCache(Handle type, Handle name, Handle code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code) { switch (state()) { case UNINITIALIZED: case PREMONOMORPHIC: case MONOMORPHIC_PROTOTYPE_FAILURE: UpdateMonomorphicIC(type, code, name); break; case MONOMORPHIC: // Fall through. case POLYMORPHIC: if (!target()->is_keyed_stub()) { if (UpdatePolymorphicIC(type, name, code)) break; CopyICToMegamorphicCache(name); } set_target(*megamorphic_stub()); // Fall through. case MEGAMORPHIC: UpdateMegamorphicCache(*type, *name, *code); break; case DEBUG_STUB: break; case GENERIC: UNREACHABLE(); break; } } Handle LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
LoadIC::initialize_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(UNINITIALIZED, extra_state); } Handle LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
LoadIC::pre_monomorphic_stub(Isolate* isolate, ExtraICState extra_state) { return isolate->stub_cache()->ComputeLoad(PREMONOMORPHIC, extra_state); } Handle LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
LoadIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeLoad(MEGAMORPHIC, extra_ic_state()); } Handle LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
LoadIC::SimpleFieldLoad(FieldIndex index) { if (kind() == Code::LOAD_IC) { LoadFieldStub stub(isolate(), index); return stub.GetCode(); } else { KeyedLoadFieldStub stub(isolate(), index); return stub.GetCode(); } } void LoadIC::UpdateCaches(LookupResult* lookup, Handle object, Handle name) { if (state() == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. set_target(*pre_monomorphic_stub()); TRACE_IC("LoadIC", name); return; } Handle type = CurrentTypeOf(object, isolate()); Handle code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code; if (!lookup->IsCacheable()) { // Bail out if the result is not cacheable. code = slow_stub(); } else if (!lookup->IsProperty()) { if (kind() == Code::LOAD_IC) { code = isolate()->stub_cache()->ComputeLoadNonexistent(name, type); } else { code = slow_stub(); } } else { code = ComputeHandler(lookup, object, name); } PatchCache(type, name, code); TRACE_IC("LoadIC", name); } void IC::UpdateMegamorphicCache(HeapType* type, Name* name, Code* code) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. Map* map = *TypeToMap(type, isolate()); isolate()->stub_cache()->Set(name, map, code); } Handle IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
IC::ComputeHandler(LookupResult* lookup, Handle object, Handle name, Handle value) { InlineCacheHolderFlag cache_holder = GetCodeCacheForObject(*object); Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); Handle code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = isolate()->stub_cache()->FindHandler( name, handle(stub_holder->map()), kind(), cache_holder, lookup->holder()->HasFastProperties() ? Code::FAST : Code::NORMAL); if (!code.is_null()) { return code; } code = CompileHandler(lookup, object, name, value, cache_holder); ASSERT(code->is_handler()); if (code->type() != Code::NORMAL) { HeapObject::UpdateMapCodeCache(stub_holder, name, code); } return code; } Handle LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
LoadIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle unused, InlineCacheHolderFlag cache_holder) { if (object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset); return SimpleFieldLoad(index); } if (object->IsStringWrapper() && String::Equals(isolate()->factory()->length_string(), name)) { if (kind() == Code::LOAD_IC) { StringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } else { KeyedStringLengthStub string_length_stub(isolate()); return string_length_stub.GetCode(); } } Handle type = CurrentTypeOf(object, isolate()); Handle holder(lookup->holder()); LoadStubCompiler compiler(isolate(), kNoExtraICState, cache_holder, kind()); switch (lookup->type()) { case FIELD: { FieldIndex field = lookup->GetFieldIndex(); if (object.is_identical_to(holder)) { return SimpleFieldLoad(field); } return compiler.CompileLoadField( type, holder, name, field, lookup->representation()); } case CONSTANT: { Handle constant(lookup->GetConstant(), isolate()); // TODO(2803): Don't compute a stub for cons strings because they cannot // be embedded into code. if (constant->IsConsString()) break; return compiler.CompileLoadConstant(type, holder, name, constant); } case NORMAL: if (kind() != Code::LOAD_IC) break; if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell( global->GetPropertyCell(lookup), isolate()); Handle code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = compiler.CompileLoadGlobal( type, global, cell, name, lookup->IsDontDelete()); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. Handle stub_holder(GetCodeCacheHolder( isolate(), *object, cache_holder)); HeapObject::UpdateMapCodeCache(stub_holder, name, code); return code; } // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the object for the stub to be // applicable. if (!object.is_identical_to(holder)) break; return isolate()->builtins()->LoadIC_Normal(); case CALLBACKS: { // Use simple field loads for some well-known callback properties. if (object->IsJSObject()) { Handle receiver = Handle::cast(object); Handle map(receiver->map()); Handle type = IC::MapToType( handle(receiver->map()), isolate()); int object_offset; if (Accessors::IsJSObjectFieldAccessor( type, name, &object_offset)) { FieldIndex index = FieldIndex::ForInObjectOffset( object_offset, receiver->map()); return SimpleFieldLoad(index); } } Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->getter()) == 0) break; if (!info->IsCompatibleReceiver(*object)) break; return compiler.CompileLoadCallback(type, holder, name, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter(), isolate()); if (!getter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(getter); if (!object->IsJSObject() && !function->IsBuiltin() && function->shared()->strict_mode() == SLOPPY) { // Calling sloppy non-builtins with a value as the receiver // requires boxing. break; } CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(object, holder)) { return compiler.CompileLoadCallback( type, holder, name, call_optimization); } return compiler.CompileLoadViaGetter(type, holder, name, function); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return compiler.CompileLoadInterceptor(type, holder, name); default: break; } return slow_stub(); } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (std::isnan(value)) { key = isolate->factory()->nan_string(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value), isolate); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_string(); } return key; } Handle KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
KeyedLoadIC::LoadElementStub(Handle receiver) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; if (target().is_identical_to(string_stub())) { target_receiver_maps.Add(isolate()->factory()->string_map()); } else { TargetMaps(&target_receiver_maps); } if (target_receiver_maps.length() == 0) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. if (state() == MONOMORPHIC && IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind())) { return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map); } ASSERT(state() != GENERIC); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } return isolate()->stub_cache()->ComputeLoadElementPolymorphic( &target_receiver_maps); } MaybeHandle KeyedLoadIC::Load(Handle object, Handle key) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } Handle load_handle; Handle stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub = generic_stub(); // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), load_handle, LoadIC::Load(object, Handle::cast(key)), Object); } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) { if (object->IsString() && key->IsNumber()) { if (state() == UNINITIALIZED) stub = string_stub(); } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { stub = sloppy_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (!Object::ToSmi(isolate(), key).is_null() && (!target().is_identical_to(sloppy_arguments_stub()))) { stub = LoadElementStub(receiver); } } } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic"); } set_target(*stub); TRACE_IC("LoadIC", key); } if (!load_handle.is_null()) return load_handle; Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::GetObjectProperty(isolate(), object, key), Object); return result; } static bool LookupForWrite(Handle receiver, Handle name, Handle value, LookupResult* lookup, IC* ic) { Handle holder = receiver; receiver->Lookup(name, lookup); if (lookup->IsFound()) { if (lookup->IsInterceptor() && !HasInterceptorSetter(lookup->holder())) { receiver->LookupOwnRealNamedProperty(name, lookup); if (!lookup->IsFound()) return false; } if (lookup->IsReadOnly() || !lookup->IsCacheable()) return false; if (lookup->holder() == *receiver) return lookup->CanHoldValue(value); if (lookup->IsPropertyCallbacks()) return true; // JSGlobalProxy either stores on the global object in the prototype, or // goes into the runtime if access checks are needed, so this is always // safe. if (receiver->IsJSGlobalProxy()) { return lookup->holder() == receiver->GetPrototype(); } // Currently normal holders in the prototype chain are not supported. They // would require a runtime positive lookup and verification that the details // have not changed. if (lookup->IsInterceptor() || lookup->IsNormal()) return false; holder = Handle(lookup->holder(), lookup->isolate()); } // While normally LookupTransition gets passed the receiver, in this case we // pass the holder of the property that we overwrite. This keeps the holder in // the LookupResult intact so we can later use it to generate a prototype // chain check. This avoids a double lookup, but requires us to pass in the // receiver when trying to fetch extra information from the transition. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition() || lookup->IsReadOnly()) return false; // If the value that's being stored does not fit in the field that the // instance would transition to, create a new transition that fits the value. // This has to be done before generating the IC, since that IC will embed the // transition target. // Ensure the instance and its map were migrated before trying to update the // transition target. ASSERT(!receiver->map()->is_deprecated()); if (!lookup->CanHoldValue(value)) { Handle target(lookup->GetTransitionTarget()); Representation field_representation = value->OptimalRepresentation(); Handle field_type = value->OptimalType( lookup->isolate(), field_representation); Map::GeneralizeRepresentation( target, target->LastAdded(), field_representation, field_type, FORCE_FIELD); // Lookup the transition again since the transition tree may have changed // entirely by the migration above. receiver->map()->LookupTransition(*holder, *name, lookup); if (!lookup->IsTransition()) return false; return ic->TryMarkMonomorphicPrototypeFailure(name); } return true; } MaybeHandle StoreIC::Store(Handle object, Handle name, Handle value, JSReceiver::StoreFromKeyed store_mode) { if (MigrateDeprecated(object) || object->IsJSProxy()) { Handle receiver = Handle::cast(object); Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty(receiver, name, value, NONE, strict_mode()), Object); return result; } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode() == STRICT && object->IsString() && String::Equals(isolate()->factory()->length_string(), name)) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. if (!object->IsJSObject()) return value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSObject::SetElement(receiver, index, value, NONE, strict_mode()), Object); return value; } // Observed objects are always modified through the runtime. if (receiver->map()->is_observed()) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } LookupResult lookup(isolate()); bool can_store = LookupForWrite(receiver, name, value, &lookup, this); if (!can_store && strict_mode() == STRICT && !(lookup.IsProperty() && lookup.IsReadOnly()) && object->IsGlobalObject()) { // Strict mode doesn't allow setting non-existent global property. return ReferenceError("not_defined", name); } if (FLAG_use_ic) { if (state() == UNINITIALIZED) { Handle stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub = pre_monomorphic_stub(); set_target(*stub); TRACE_IC("StoreIC", name); } else if (can_store) { UpdateCaches(&lookup, receiver, name, value); } else if (lookup.IsNormal() || (lookup.IsField() && lookup.CanHoldValue(value))) { Handle stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub = generic_stub(); set_target(*stub); } } // Set the property. Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, JSReceiver::SetProperty( receiver, name, value, NONE, strict_mode(), store_mode), Object); return result; } void CallIC::State::Print(StringStream* stream) const { stream->Add("(args(%d), ", argc_); stream->Add("%s, ", call_type_ == CallIC::METHOD ? "METHOD" : "FUNCTION"); } Handle CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
CallIC::initialize_stub(Isolate* isolate, int argc, CallType call_type) { CallICStub stub(isolate, State(argc, call_type)); Handle code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = stub.GetCode(); return code; } Handle StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
StoreIC::initialize_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState extra_state = ComputeExtraICState(strict_mode); Handle ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
ic = isolate->stub_cache()->ComputeStore( UNINITIALIZED, extra_state); return ic; } Handle StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
StoreIC::megamorphic_stub() { return isolate()->stub_cache()->ComputeStore(MEGAMORPHIC, extra_ic_state()); } Handle StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
StoreIC::generic_stub() const { return isolate()->stub_cache()->ComputeStore(GENERIC, extra_ic_state()); } Handle StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
StoreIC::pre_monomorphic_stub(Isolate* isolate, StrictMode strict_mode) { ExtraICState state = ComputeExtraICState(strict_mode); return isolate->stub_cache()->ComputeStore(PREMONOMORPHIC, state); } void StoreIC::UpdateCaches(LookupResult* lookup, Handle receiver, Handle name, Handle value) { ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); Handle code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = ComputeHandler(lookup, receiver, name, value); PatchCache(CurrentTypeOf(receiver, isolate()), name, code); TRACE_IC("StoreIC", name); } Handle StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
StoreIC::CompileHandler(LookupResult* lookup, Handle object, Handle name, Handle value, InlineCacheHolderFlag cache_holder) { if (object->IsAccessCheckNeeded()) return slow_stub(); ASSERT(cache_holder == OWN_MAP); // This is currently guaranteed by checks in StoreIC::Store. Handle receiver = Handle::cast(object); Handle holder(lookup->holder()); // Handlers do not use strict mode. StoreStubCompiler compiler(isolate(), SLOPPY, kind()); if (lookup->IsTransition()) { // Explicitly pass in the receiver map since LookupForWrite may have // stored something else than the receiver in the holder. Handle transition(lookup->GetTransitionTarget()); PropertyDetails details = lookup->GetPropertyDetails(); if (details.type() != CALLBACKS && details.attributes() == NONE) { return compiler.CompileStoreTransition( receiver, lookup, transition, name); } } else { switch (lookup->type()) { case FIELD: return compiler.CompileStoreField(receiver, lookup, name); case NORMAL: if (kind() == Code::KEYED_STORE_IC) break; if (receiver->IsJSGlobalProxy() || receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = receiver->IsJSGlobalProxy() ? handle(GlobalObject::cast(receiver->GetPrototype())) : Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup), isolate()); Handle union_type = PropertyCell::UpdatedType(cell, value); StoreGlobalStub stub( isolate(), union_type->IsConstant(), receiver->IsJSGlobalProxy()); Handle code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = stub.GetCodeCopyFromTemplate(global, cell); // TODO(verwaest): Move caching of these NORMAL stubs outside as well. HeapObject::UpdateMapCodeCache(receiver, name, code); return code; } ASSERT(holder.is_identical_to(receiver)); return isolate()->builtins()->StoreIC_Normal(); case CALLBACKS: { Handle callback(lookup->GetCallbackObject(), isolate()); if (callback->IsExecutableAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData(info->setter()) == 0) break; if (!holder->HasFastProperties()) break; if (!info->IsCompatibleReceiver(*receiver)) break; return compiler.CompileStoreCallback(receiver, holder, name, info); } else if (callback->IsAccessorPair()) { Handle setter( Handle::cast(callback)->setter(), isolate()); if (!setter->IsJSFunction()) break; if (holder->IsGlobalObject()) break; if (!holder->HasFastProperties()) break; Handle function = Handle::cast(setter); CallOptimization call_optimization(function); if (call_optimization.is_simple_api_call() && call_optimization.IsCompatibleReceiver(receiver, holder)) { return compiler.CompileStoreCallback( receiver, holder, name, call_optimization); } return compiler.CompileStoreViaSetter( receiver, holder, name, Handle::cast(setter)); } // TODO(dcarney): Handle correctly. ASSERT(callback->IsDeclaredAccessorInfo()); break; } case INTERCEPTOR: if (kind() == Code::KEYED_STORE_IC) break; ASSERT(HasInterceptorSetter(*holder)); return compiler.CompileStoreInterceptor(receiver, name); case CONSTANT: break; case NONEXISTENT: case HANDLER: UNREACHABLE(); break; } } return slow_stub(); } Handle KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
KeyedStoreIC::StoreElementStub(Handle receiver, KeyedAccessStoreMode store_mode) { // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "non-NORMAL target type"); return generic_stub(); } Handle receiver_map(receiver->map(), isolate()); MapHandleList target_receiver_maps; TargetMaps(&target_receiver_maps); if (target_receiver_maps.length() == 0) { Handle monomorphic_map = ComputeTransitionedMap(receiver_map, store_mode); store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( monomorphic_map, strict_mode(), store_mode); } // There are several special cases where an IC that is MONOMORPHIC can still // transition to a different GetNonTransitioningStoreMode IC that handles a // superset of the original IC. Handle those here if the receiver map hasn't // changed or it has transitioned to a more general kind. KeyedAccessStoreMode old_store_mode = KeyedStoreIC::GetKeyedAccessStoreMode(target()->extra_ic_state()); Handle previous_receiver_map = target_receiver_maps.at(0); if (state() == MONOMORPHIC) { Handle transitioned_receiver_map = receiver_map; if (IsTransitionStoreMode(store_mode)) { transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); } if ((receiver_map.is_identical_to(previous_receiver_map) && IsTransitionStoreMode(store_mode)) || IsTransitionOfMonomorphicTarget(*previous_receiver_map, *transitioned_receiver_map)) { // If the "old" and "new" maps are in the same elements map family, or // if they at least come from the same origin for a transitioning store, // stay MONOMORPHIC and use the map for the most generic ElementsKind. store_mode = GetNonTransitioningStoreMode(store_mode); return isolate()->stub_cache()->ComputeKeyedStoreElement( transitioned_receiver_map, strict_mode(), store_mode); } else if (*previous_receiver_map == receiver->map() && old_store_mode == STANDARD_STORE && (store_mode == STORE_AND_GROW_NO_TRANSITION || store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS || store_mode == STORE_NO_TRANSITION_HANDLE_COW)) { // A "normal" IC that handles stores can switch to a version that can // grow at the end of the array, handle OOB accesses or copy COW arrays // and still stay MONOMORPHIC. return isolate()->stub_cache()->ComputeKeyedStoreElement( receiver_map, strict_mode(), store_mode); } } ASSERT(state() != GENERIC); bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStoreMode(store_mode)) { Handle transitioned_receiver_map = ComputeTransitionedMap(receiver_map, store_mode); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, transitioned_receiver_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC(isolate(), "KeyedIC", "same map added twice"); return generic_stub(); } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "max polymorph exceeded"); return generic_stub(); } // Make sure all polymorphic handlers have the same store mode, otherwise the // generic stub must be used. store_mode = GetNonTransitioningStoreMode(store_mode); if (old_store_mode != STANDARD_STORE) { if (store_mode == STANDARD_STORE) { store_mode = old_store_mode; } else if (store_mode != old_store_mode) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "store mode mismatch"); return generic_stub(); } } // If the store mode isn't the standard mode, make sure that all polymorphic // receivers are either external arrays, or all "normal" arrays. Otherwise, // use the generic stub. if (store_mode != STANDARD_STORE) { int external_arrays = 0; for (int i = 0; i < target_receiver_maps.length(); ++i) { if (target_receiver_maps[i]->has_external_array_elements() || target_receiver_maps[i]->has_fixed_typed_array_elements()) { external_arrays++; } } if (external_arrays != 0 && external_arrays != target_receiver_maps.length()) { TRACE_GENERIC_IC(isolate(), "KeyedIC", "unsupported combination of external and normal arrays"); return generic_stub(); } } return isolate()->stub_cache()->ComputeStoreElementPolymorphic( &target_receiver_maps, store_mode, strict_mode()); } Handle KeyedStoreIC::ComputeTransitionedMap( Handle map, KeyedAccessStoreMode store_mode) { switch (store_mode) { case STORE_TRANSITION_SMI_TO_OBJECT: case STORE_TRANSITION_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_ELEMENTS); case STORE_TRANSITION_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_DOUBLE_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return Map::TransitionElementsTo(map, FAST_HOLEY_ELEMENTS); case STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return Map::TransitionElementsTo(map, FAST_HOLEY_DOUBLE_ELEMENTS); case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS: ASSERT(map->has_external_array_elements()); // Fall through case STORE_NO_TRANSITION_HANDLE_COW: case STANDARD_STORE: case STORE_AND_GROW_NO_TRANSITION: return map; } UNREACHABLE(); return MaybeHandle().ToHandleChecked(); } bool IsOutOfBoundsAccess(Handle receiver, int index) { if (receiver->IsJSArray()) { return JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); } return index >= receiver->elements()->length(); } KeyedAccessStoreMode KeyedStoreIC::GetStoreMode(Handle receiver, Handle key, Handle value) { Handle smi_key = Object::ToSmi(isolate(), key).ToHandleChecked(); int index = smi_key->value(); bool oob_access = IsOutOfBoundsAccess(receiver, index); // Don't consider this a growing store if the store would send the receiver to // dictionary mode. bool allow_growth = receiver->IsJSArray() && oob_access && !receiver->WouldConvertToSlowElements(key); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } if (!FLAG_trace_external_array_abuse && receiver->map()->has_external_array_elements() && oob_access) { return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS; } Heap* heap = receiver->GetHeap(); if (receiver->elements()->map() == heap->fixed_cow_array_map()) { return STORE_NO_TRANSITION_HANDLE_COW; } else { return STANDARD_STORE; } } } MaybeHandle KeyedStoreIC::Store(Handle object, Handle key, Handle value) { if (MigrateDeprecated(object)) { Handle result; ASSIGN_RETURN_ON_EXCEPTION( isolate(), result, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); return result; } // Check for non-string values that can be converted into an // internalized string directly or is representable as a smi. key = TryConvertKey(key, isolate()); Handle store_handle; Handle stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
stub = generic_stub(); if (key->IsInternalizedString()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, StoreIC::Store(object, Handle::cast(key), value, JSReceiver::MAY_BE_STORE_FROM_KEYED), Object); } else { bool use_ic = FLAG_use_ic && !object->IsStringWrapper() && !object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() && !(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); if (use_ic && !object->IsSmi()) { // Don't use ICs for maps of the objects in Array's prototype chain. We // expect to be able to trap element sets to objects with those maps in // the runtime to enable optimization of element hole access. Handle heap_object = Handle::cast(object); if (heap_object->map()->IsMapInArrayPrototypeChain()) use_ic = false; } if (use_ic) { ASSERT(!object->IsAccessCheckNeeded()); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); bool key_is_smi_like = !Object::ToSmi(isolate(), key).is_null(); if (receiver->elements()->map() == isolate()->heap()->sloppy_arguments_elements_map()) { if (strict_mode() == SLOPPY) { stub = sloppy_arguments_stub(); } } else if (key_is_smi_like && !(target().is_identical_to(sloppy_arguments_stub()))) { // We should go generic if receiver isn't a dictionary, but our // prototype chain does have dictionary elements. This ensures that // other non-dictionary receivers in the polymorphic case benefit // from fast path keyed stores. if (!(receiver->map()->DictionaryElementsInPrototypeChainOnly())) { KeyedAccessStoreMode store_mode = GetStoreMode(receiver, key, value); stub = StoreElementStub(receiver, store_mode); } } } } } if (store_handle.is_null()) { ASSIGN_RETURN_ON_EXCEPTION( isolate(), store_handle, Runtime::SetObjectProperty( isolate(), object, key, value, NONE, strict_mode()), Object); } if (!is_target_set()) { Code* generic = *generic_stub(); if (*stub == generic) { TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "set generic"); } ASSERT(!stub.is_null()); set_target(*stub); TRACE_IC("StoreIC", key); } return store_handle; } CallIC::State::State(ExtraICState extra_ic_state) : argc_(ArgcBits::decode(extra_ic_state)), call_type_(CallTypeBits::decode(extra_ic_state)) { } ExtraICState CallIC::State::GetExtraICState() const { ExtraICState extra_ic_state = ArgcBits::encode(argc_) | CallTypeBits::encode(call_type_); return extra_ic_state; } bool CallIC::DoCustomHandler(Handle receiver, Handle function, Handle vector, Handle slot, const State& state) { ASSERT(FLAG_use_ic && function->IsJSFunction()); // Are we the array function? Handle array_function = Handle( isolate()->context()->native_context()->array_function(), isolate()); if (array_function.is_identical_to(Handle::cast(function))) { // Alter the slot. Object* feedback = vector->get(slot->value()); if (!feedback->IsAllocationSite()) { Handle new_site = isolate()->factory()->NewAllocationSite(); vector->set(slot->value(), *new_site); } CallIC_ArrayStub stub(isolate(), state); set_target(*stub.GetCode()); Handle name; if (array_function->shared()->name()->IsString()) { name = Handle(String::cast(array_function->shared()->name()), isolate()); } TRACE_IC("CallIC (Array call)", name); return true; } return false; } void CallIC::PatchMegamorphic(Handle vector, Handle slot) { State state(target()->extra_ic_state()); // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); CallICStub stub(isolate(), state); Handle code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle
code = stub.GetCode(); set_target(*code); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } void CallIC::HandleMiss(Handle receiver, Handle function, Handle vector, Handle slot) { State state(target()->extra_ic_state()); Object* feedback = vector->get(slot->value()); // Hand-coded MISS handling is easier if CallIC slots don't contain smis. ASSERT(!feedback->IsSmi()); if (feedback->IsJSFunction() || !function->IsJSFunction()) { // We are going generic. vector->set(slot->value(), *TypeFeedbackInfo::MegamorphicSentinel(isolate()), SKIP_WRITE_BARRIER); TRACE_GENERIC_IC(isolate(), "CallIC", "megamorphic"); } else { // The feedback is either uninitialized or an allocation site. // It might be an allocation site because if we re-compile the full code // to add deoptimization support, we call with the default call-ic, and // merely need to patch the target to match the feedback. // TODO(mvstanton): the better approach is to dispense with patching // altogether, which is in progress. ASSERT(feedback == *TypeFeedbackInfo::UninitializedSentinel(isolate()) || feedback->IsAllocationSite()); // Do we want to install a custom handler? if (FLAG_use_ic && DoCustomHandler(receiver, function, vector, slot, state)) { return; } Handle js_function = Handle::cast(function); Handle name(js_function->shared()->name(), isolate()); TRACE_IC("CallIC", name); vector->set(slot->value(), *function); } } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(CallIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); CallIC ic(isolate); Handle receiver = args.at(0); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.HandleMiss(receiver, function, vector, slot); return *function; } RUNTIME_FUNCTION(CallIC_Customization_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 4); // A miss on a custom call ic always results in going megamorphic. CallIC ic(isolate); Handle function = args.at(1); Handle vector = args.at(2); Handle slot = args.at(3); ic.PatchMegamorphic(vector, slot); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(LoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle receiver = args.at(0); Handle key = args.at(1); ic.UpdateState(receiver, key); Handle result; ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key)); return *result; } // Used from ic-.cc RUNTIME_FUNCTION(KeyedLoadIC_Miss) { Logger::TimerEventScope timer( isolate, Logger::TimerEventScope::v8_ic_miss); HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate); Handle