// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "v8.h"
#include "api.h"
#include "arguments.h"
#include "bootstrapper.h"
#include "codegen.h"
#include "debug.h"
#include "deoptimizer.h"
#include "date.h"
#include "elements.h"
#include "execution.h"
#include "full-codegen.h"
#include "hydrogen.h"
#include "objects-inl.h"
#include "objects-visiting.h"
#include "objects-visiting-inl.h"
#include "macro-assembler.h"
#include "mark-compact.h"
#include "safepoint-table.h"
#include "string-stream.h"
#include "utils.h"
#include "vm-state-inl.h"
#ifdef ENABLE_DISASSEMBLER
#include "disasm.h"
#include "disassembler.h"
#endif
namespace v8 {
namespace internal {
void PrintElementsKind(FILE* out, ElementsKind kind) {
ElementsAccessor* accessor = ElementsAccessor::ForKind(kind);
PrintF(out, "%s", accessor->name());
}
MUST_USE_RESULT static MaybeObject* CreateJSValue(JSFunction* constructor,
Object* value) {
Object* result;
{ MaybeObject* maybe_result =
constructor->GetHeap()->AllocateJSObject(constructor);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
JSValue::cast(result)->set_value(value);
return result;
}
MaybeObject* Object::ToObject(Context* global_context) {
if (IsNumber()) {
return CreateJSValue(global_context->number_function(), this);
} else if (IsBoolean()) {
return CreateJSValue(global_context->boolean_function(), this);
} else if (IsString()) {
return CreateJSValue(global_context->string_function(), this);
}
ASSERT(IsJSObject());
return this;
}
MaybeObject* Object::ToObject() {
if (IsJSReceiver()) {
return this;
} else if (IsNumber()) {
Isolate* isolate = Isolate::Current();
Context* global_context = isolate->context()->global_context();
return CreateJSValue(global_context->number_function(), this);
} else if (IsBoolean()) {
Isolate* isolate = HeapObject::cast(this)->GetIsolate();
Context* global_context = isolate->context()->global_context();
return CreateJSValue(global_context->boolean_function(), this);
} else if (IsString()) {
Isolate* isolate = HeapObject::cast(this)->GetIsolate();
Context* global_context = isolate->context()->global_context();
return CreateJSValue(global_context->string_function(), this);
}
// Throw a type error.
return Failure::InternalError();
}
Object* Object::ToBoolean() {
if (IsTrue()) return this;
if (IsFalse()) return this;
if (IsSmi()) {
return Isolate::Current()->heap()->ToBoolean(Smi::cast(this)->value() != 0);
}
HeapObject* heap_object = HeapObject::cast(this);
if (heap_object->IsUndefined() || heap_object->IsNull()) {
return heap_object->GetHeap()->false_value();
}
// Undetectable object is false
if (heap_object->IsUndetectableObject()) {
return heap_object->GetHeap()->false_value();
}
if (heap_object->IsString()) {
return heap_object->GetHeap()->ToBoolean(
String::cast(this)->length() != 0);
}
if (heap_object->IsHeapNumber()) {
return HeapNumber::cast(this)->HeapNumberToBoolean();
}
return heap_object->GetHeap()->true_value();
}
void Object::Lookup(String* name, LookupResult* result) {
Object* holder = NULL;
if (IsJSReceiver()) {
holder = this;
} else {
Context* global_context = Isolate::Current()->context()->global_context();
if (IsNumber()) {
holder = global_context->number_function()->instance_prototype();
} else if (IsString()) {
holder = global_context->string_function()->instance_prototype();
} else if (IsBoolean()) {
holder = global_context->boolean_function()->instance_prototype();
}
}
ASSERT(holder != NULL); // Cannot handle null or undefined.
JSReceiver::cast(holder)->Lookup(name, result);
}
MaybeObject* Object::GetPropertyWithReceiver(Object* receiver,
String* name,
PropertyAttributes* attributes) {
LookupResult result(name->GetIsolate());
Lookup(name, &result);
MaybeObject* value = GetProperty(receiver, &result, name, attributes);
ASSERT(*attributes <= ABSENT);
return value;
}
MaybeObject* JSObject::GetPropertyWithCallback(Object* receiver,
Object* structure,
String* name) {
Isolate* isolate = name->GetIsolate();
// To accommodate both the old and the new api we switch on the
// data structure used to store the callbacks. Eventually foreign
// callbacks should be phased out.
if (structure->IsForeign()) {
AccessorDescriptor* callback =
reinterpret_cast<AccessorDescriptor*>(
Foreign::cast(structure)->foreign_address());
MaybeObject* value = (callback->getter)(receiver, callback->data);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return value;
}
// api style callbacks.
if (structure->IsAccessorInfo()) {
AccessorInfo* data = AccessorInfo::cast(structure);
Object* fun_obj = data->getter();
v8::AccessorGetter call_fun = v8::ToCData<v8::AccessorGetter>(fun_obj);
HandleScope scope(isolate);
JSObject* self = JSObject::cast(receiver);
Handle<String> key(name);
LOG(isolate, ApiNamedPropertyAccess("load", self, name));
CustomArguments args(isolate, data->data(), self, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = call_fun(v8::Utils::ToLocal(key), info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (result.IsEmpty()) {
return isolate->heap()->undefined_value();
}
return *v8::Utils::OpenHandle(*result);
}
// __defineGetter__ callback
if (structure->IsAccessorPair()) {
Object* getter = AccessorPair::cast(structure)->getter();
if (getter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return GetPropertyWithDefinedGetter(receiver, JSReceiver::cast(getter));
}
// Getter is not a function.
return isolate->heap()->undefined_value();
}
UNREACHABLE();
return NULL;
}
MaybeObject* JSProxy::GetPropertyWithHandler(Object* receiver_raw,
String* name_raw) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<Object> receiver(receiver_raw);
Handle<Object> name(name_raw);
Handle<Object> args[] = { receiver, name };
Handle<Object> result = CallTrap(
"get", isolate->derived_get_trap(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return Failure::Exception();
return *result;
}
Handle<Object> Object::GetElement(Handle<Object> object, uint32_t index) {
Isolate* isolate = object->IsHeapObject()
? Handle<HeapObject>::cast(object)->GetIsolate()
: Isolate::Current();
CALL_HEAP_FUNCTION(isolate, object->GetElement(index), Object);
}
MaybeObject* JSProxy::GetElementWithHandler(Object* receiver,
uint32_t index) {
String* name;
MaybeObject* maybe = GetHeap()->Uint32ToString(index);
if (!maybe->To<String>(&name)) return maybe;
return GetPropertyWithHandler(receiver, name);
}
MaybeObject* JSProxy::SetElementWithHandler(uint32_t index,
Object* value,
StrictModeFlag strict_mode) {
String* name;
MaybeObject* maybe = GetHeap()->Uint32ToString(index);
if (!maybe->To<String>(&name)) return maybe;
return SetPropertyWithHandler(name, value, NONE, strict_mode);
}
bool JSProxy::HasElementWithHandler(uint32_t index) {
String* name;
MaybeObject* maybe = GetHeap()->Uint32ToString(index);
if (!maybe->To<String>(&name)) return maybe;
return HasPropertyWithHandler(name);
}
MaybeObject* Object::GetPropertyWithDefinedGetter(Object* receiver,
JSReceiver* getter) {
HandleScope scope;
Handle<JSReceiver> fun(getter);
Handle<Object> self(receiver);
#ifdef ENABLE_DEBUGGER_SUPPORT
Debug* debug = fun->GetHeap()->isolate()->debug();
// Handle stepping into a getter if step into is active.
// TODO(rossberg): should this apply to getters that are function proxies?
if (debug->StepInActive() && fun->IsJSFunction()) {
debug->HandleStepIn(
Handle<JSFunction>::cast(fun), Handle<Object>::null(), 0, false);
}
#endif
bool has_pending_exception;
Handle<Object> result =
Execution::Call(fun, self, 0, NULL, &has_pending_exception, true);
// Check for pending exception and return the result.
if (has_pending_exception) return Failure::Exception();
return *result;
}
// Only deal with CALLBACKS and INTERCEPTOR
MaybeObject* JSObject::GetPropertyWithFailedAccessCheck(
Object* receiver,
LookupResult* result,
String* name,
PropertyAttributes* attributes) {
if (result->IsProperty()) {
switch (result->type()) {
case CALLBACKS: {
// Only allow API accessors.
Object* obj = result->GetCallbackObject();
if (obj->IsAccessorInfo()) {
AccessorInfo* info = AccessorInfo::cast(obj);
if (info->all_can_read()) {
*attributes = result->GetAttributes();
return result->holder()->GetPropertyWithCallback(
receiver, result->GetCallbackObject(), name);
}
}
break;
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION: {
// Search ALL_CAN_READ accessors in prototype chain.
LookupResult r(GetIsolate());
result->holder()->LookupRealNamedPropertyInPrototypes(name, &r);
if (r.IsProperty()) {
return GetPropertyWithFailedAccessCheck(receiver,
&r,
name,
attributes);
}
break;
}
case INTERCEPTOR: {
// If the object has an interceptor, try real named properties.
// No access check in GetPropertyAttributeWithInterceptor.
LookupResult r(GetIsolate());
result->holder()->LookupRealNamedProperty(name, &r);
if (r.IsProperty()) {
return GetPropertyWithFailedAccessCheck(receiver,
&r,
name,
attributes);
}
break;
}
default:
UNREACHABLE();
}
}
// No accessible property found.
*attributes = ABSENT;
Heap* heap = name->GetHeap();
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_GET);
return heap->undefined_value();
}
PropertyAttributes JSObject::GetPropertyAttributeWithFailedAccessCheck(
Object* receiver,
LookupResult* result,
String* name,
bool continue_search) {
if (result->IsProperty()) {
switch (result->type()) {
case CALLBACKS: {
// Only allow API accessors.
Object* obj = result->GetCallbackObject();
if (obj->IsAccessorInfo()) {
AccessorInfo* info = AccessorInfo::cast(obj);
if (info->all_can_read()) {
return result->GetAttributes();
}
}
break;
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION: {
if (!continue_search) break;
// Search ALL_CAN_READ accessors in prototype chain.
LookupResult r(GetIsolate());
result->holder()->LookupRealNamedPropertyInPrototypes(name, &r);
if (r.IsProperty()) {
return GetPropertyAttributeWithFailedAccessCheck(receiver,
&r,
name,
continue_search);
}
break;
}
case INTERCEPTOR: {
// If the object has an interceptor, try real named properties.
// No access check in GetPropertyAttributeWithInterceptor.
LookupResult r(GetIsolate());
if (continue_search) {
result->holder()->LookupRealNamedProperty(name, &r);
} else {
result->holder()->LocalLookupRealNamedProperty(name, &r);
}
if (r.IsProperty()) {
return GetPropertyAttributeWithFailedAccessCheck(receiver,
&r,
name,
continue_search);
}
break;
}
default:
UNREACHABLE();
}
}
GetIsolate()->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return ABSENT;
}
Object* JSObject::GetNormalizedProperty(LookupResult* result) {
ASSERT(!HasFastProperties());
Object* value = property_dictionary()->ValueAt(result->GetDictionaryEntry());
if (IsGlobalObject()) {
value = JSGlobalPropertyCell::cast(value)->value();
}
ASSERT(!value->IsJSGlobalPropertyCell());
return value;
}
Object* JSObject::SetNormalizedProperty(LookupResult* result, Object* value) {
ASSERT(!HasFastProperties());
if (IsGlobalObject()) {
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(
property_dictionary()->ValueAt(result->GetDictionaryEntry()));
cell->set_value(value);
} else {
property_dictionary()->ValueAtPut(result->GetDictionaryEntry(), value);
}
return value;
}
Handle<Object> JSObject::SetNormalizedProperty(Handle<JSObject> object,
Handle<String> key,
Handle<Object> value,
PropertyDetails details) {
CALL_HEAP_FUNCTION(object->GetIsolate(),
object->SetNormalizedProperty(*key, *value, details),
Object);
}
MaybeObject* JSObject::SetNormalizedProperty(String* name,
Object* value,
PropertyDetails details) {
ASSERT(!HasFastProperties());
int entry = property_dictionary()->FindEntry(name);
if (entry == StringDictionary::kNotFound) {
Object* store_value = value;
if (IsGlobalObject()) {
Heap* heap = name->GetHeap();
MaybeObject* maybe_store_value =
heap->AllocateJSGlobalPropertyCell(value);
if (!maybe_store_value->ToObject(&store_value)) return maybe_store_value;
}
Object* dict;
{ MaybeObject* maybe_dict =
property_dictionary()->Add(name, store_value, details);
if (!maybe_dict->ToObject(&dict)) return maybe_dict;
}
set_properties(StringDictionary::cast(dict));
return value;
}
// Preserve enumeration index.
details = PropertyDetails(details.attributes(),
details.type(),
property_dictionary()->DetailsAt(entry).index());
if (IsGlobalObject()) {
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(property_dictionary()->ValueAt(entry));
cell->set_value(value);
// Please note we have to update the property details.
property_dictionary()->DetailsAtPut(entry, details);
} else {
property_dictionary()->SetEntry(entry, name, value, details);
}
return value;
}
MaybeObject* JSObject::DeleteNormalizedProperty(String* name, DeleteMode mode) {
ASSERT(!HasFastProperties());
StringDictionary* dictionary = property_dictionary();
int entry = dictionary->FindEntry(name);
if (entry != StringDictionary::kNotFound) {
// If we have a global object set the cell to the hole.
if (IsGlobalObject()) {
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.IsDontDelete()) {
if (mode != FORCE_DELETION) return GetHeap()->false_value();
// When forced to delete global properties, we have to make a
// map change to invalidate any ICs that think they can load
// from the DontDelete cell without checking if it contains
// the hole value.
Object* new_map;
{ MaybeObject* maybe_new_map = map()->CopyDropDescriptors();
if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
}
set_map(Map::cast(new_map));
}
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(dictionary->ValueAt(entry));
cell->set_value(cell->GetHeap()->the_hole_value());
dictionary->DetailsAtPut(entry, details.AsDeleted());
} else {
Object* deleted = dictionary->DeleteProperty(entry, mode);
if (deleted == GetHeap()->true_value()) {
FixedArray* new_properties = NULL;
MaybeObject* maybe_properties = dictionary->Shrink(name);
if (!maybe_properties->To(&new_properties)) {
return maybe_properties;
}
set_properties(new_properties);
}
return deleted;
}
}
return GetHeap()->true_value();
}
bool JSObject::IsDirty() {
Object* cons_obj = map()->constructor();
if (!cons_obj->IsJSFunction())
return true;
JSFunction* fun = JSFunction::cast(cons_obj);
if (!fun->shared()->IsApiFunction())
return true;
// If the object is fully fast case and has the same map it was
// created with then no changes can have been made to it.
return map() != fun->initial_map()
|| !HasFastElements()
|| !HasFastProperties();
}
Handle<Object> Object::GetProperty(Handle<Object> object,
Handle<Object> receiver,
LookupResult* result,
Handle<String> key,
PropertyAttributes* attributes) {
Isolate* isolate = object->IsHeapObject()
? Handle<HeapObject>::cast(object)->GetIsolate()
: Isolate::Current();
CALL_HEAP_FUNCTION(
isolate,
object->GetProperty(*receiver, result, *key, attributes),
Object);
}
MaybeObject* Object::GetProperty(Object* receiver,
LookupResult* result,
String* name,
PropertyAttributes* attributes) {
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
Heap* heap = name->GetHeap();
// Traverse the prototype chain from the current object (this) to
// the holder and check for access rights. This avoids traversing the
// objects more than once in case of interceptors, because the
// holder will always be the interceptor holder and the search may
// only continue with a current object just after the interceptor
// holder in the prototype chain.
// Proxy handlers do not use the proxy's prototype, so we can skip this.
if (!result->IsHandler()) {
Object* last = result->IsProperty()
? result->holder()
: Object::cast(heap->null_value());
ASSERT(this != this->GetPrototype());
for (Object* current = this; true; current = current->GetPrototype()) {
if (current->IsAccessCheckNeeded()) {
// Check if we're allowed to read from the current object. Note
// that even though we may not actually end up loading the named
// property from the current object, we still check that we have
// access to it.
JSObject* checked = JSObject::cast(current);
if (!heap->isolate()->MayNamedAccess(checked, name, v8::ACCESS_GET)) {
return checked->GetPropertyWithFailedAccessCheck(receiver,
result,
name,
attributes);
}
}
// Stop traversing the chain once we reach the last object in the
// chain; either the holder of the result or null in case of an
// absent property.
if (current == last) break;
}
}
if (!result->IsProperty()) {
*attributes = ABSENT;
return heap->undefined_value();
}
*attributes = result->GetAttributes();
Object* value;
switch (result->type()) {
case NORMAL:
value = result->holder()->GetNormalizedProperty(result);
ASSERT(!value->IsTheHole() || result->IsReadOnly());
return value->IsTheHole() ? heap->undefined_value() : value;
case FIELD:
value = result->holder()->FastPropertyAt(result->GetFieldIndex());
ASSERT(!value->IsTheHole() || result->IsReadOnly());
return value->IsTheHole() ? heap->undefined_value() : value;
case CONSTANT_FUNCTION:
return result->GetConstantFunction();
case CALLBACKS:
return result->holder()->GetPropertyWithCallback(
receiver, result->GetCallbackObject(), name);
case HANDLER:
return result->proxy()->GetPropertyWithHandler(receiver, name);
case INTERCEPTOR: {
JSObject* recvr = JSObject::cast(receiver);
return result->holder()->GetPropertyWithInterceptor(
recvr, name, attributes);
}
case MAP_TRANSITION:
case ELEMENTS_TRANSITION:
case CONSTANT_TRANSITION:
case NULL_DESCRIPTOR:
break;
}
UNREACHABLE();
return NULL;
}
MaybeObject* Object::GetElementWithReceiver(Object* receiver, uint32_t index) {
Heap* heap = IsSmi()
? Isolate::Current()->heap()
: HeapObject::cast(this)->GetHeap();
Object* holder = this;
// Iterate up the prototype chain until an element is found or the null
// prototype is encountered.
for (holder = this;
holder != heap->null_value();
holder = holder->GetPrototype()) {
if (!holder->IsJSObject()) {
Isolate* isolate = heap->isolate();
Context* global_context = isolate->context()->global_context();
if (holder->IsNumber()) {
holder = global_context->number_function()->instance_prototype();
} else if (holder->IsString()) {
holder = global_context->string_function()->instance_prototype();
} else if (holder->IsBoolean()) {
holder = global_context->boolean_function()->instance_prototype();
} else if (holder->IsJSProxy()) {
return JSProxy::cast(holder)->GetElementWithHandler(receiver, index);
} else {
// Undefined and null have no indexed properties.
ASSERT(holder->IsUndefined() || holder->IsNull());
return heap->undefined_value();
}
}
// Inline the case for JSObjects. Doing so significantly improves the
// performance of fetching elements where checking the prototype chain is
// necessary.
JSObject* js_object = JSObject::cast(holder);
// Check access rights if needed.
if (js_object->IsAccessCheckNeeded()) {
Isolate* isolate = heap->isolate();
if (!isolate->MayIndexedAccess(js_object, index, v8::ACCESS_GET)) {
isolate->ReportFailedAccessCheck(js_object, v8::ACCESS_GET);
return heap->undefined_value();
}
}
if (js_object->HasIndexedInterceptor()) {
return js_object->GetElementWithInterceptor(receiver, index);
}
if (js_object->elements() != heap->empty_fixed_array()) {
MaybeObject* result = js_object->GetElementsAccessor()->Get(
receiver, js_object, index);
if (result != heap->the_hole_value()) return result;
}
}
return heap->undefined_value();
}
Object* Object::GetPrototype() {
if (IsSmi()) {
Heap* heap = Isolate::Current()->heap();
Context* context = heap->isolate()->context()->global_context();
return context->number_function()->instance_prototype();
}
HeapObject* heap_object = HeapObject::cast(this);
// The object is either a number, a string, a boolean,
// a real JS object, or a Harmony proxy.
if (heap_object->IsJSReceiver()) {
return heap_object->map()->prototype();
}
Heap* heap = heap_object->GetHeap();
Context* context = heap->isolate()->context()->global_context();
if (heap_object->IsHeapNumber()) {
return context->number_function()->instance_prototype();
}
if (heap_object->IsString()) {
return context->string_function()->instance_prototype();
}
if (heap_object->IsBoolean()) {
return context->boolean_function()->instance_prototype();
} else {
return heap->null_value();
}
}
MaybeObject* Object::GetHash(CreationFlag flag) {
// The object is either a number, a string, an odd-ball,
// a real JS object, or a Harmony proxy.
if (IsNumber()) {
uint32_t hash = ComputeLongHash(double_to_uint64(Number()));
return Smi::FromInt(hash & Smi::kMaxValue);
}
if (IsString()) {
uint32_t hash = String::cast(this)->Hash();
return Smi::FromInt(hash);
}
if (IsOddball()) {
uint32_t hash = Oddball::cast(this)->to_string()->Hash();
return Smi::FromInt(hash);
}
if (IsJSReceiver()) {
return JSReceiver::cast(this)->GetIdentityHash(flag);
}
UNREACHABLE();
return Smi::FromInt(0);
}
bool Object::SameValue(Object* other) {
if (other == this) return true;
if (!IsHeapObject() || !other->IsHeapObject()) return false;
// The object is either a number, a string, an odd-ball,
// a real JS object, or a Harmony proxy.
if (IsNumber() && other->IsNumber()) {
double this_value = Number();
double other_value = other->Number();
return (this_value == other_value) ||
(isnan(this_value) && isnan(other_value));
}
if (IsString() && other->IsString()) {
return String::cast(this)->Equals(String::cast(other));
}
return false;
}
void Object::ShortPrint(FILE* out) {
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
ShortPrint(&accumulator);
accumulator.OutputToFile(out);
}
void Object::ShortPrint(StringStream* accumulator) {
if (IsSmi()) {
Smi::cast(this)->SmiPrint(accumulator);
} else if (IsFailure()) {
Failure::cast(this)->FailurePrint(accumulator);
} else {
HeapObject::cast(this)->HeapObjectShortPrint(accumulator);
}
}
void Smi::SmiPrint(FILE* out) {
PrintF(out, "%d", value());
}
void Smi::SmiPrint(StringStream* accumulator) {
accumulator->Add("%d", value());
}
void Failure::FailurePrint(StringStream* accumulator) {
accumulator->Add("Failure(%p)", reinterpret_cast<void*>(value()));
}
void Failure::FailurePrint(FILE* out) {
PrintF(out, "Failure(%p)", reinterpret_cast<void*>(value()));
}
// Should a word be prefixed by 'a' or 'an' in order to read naturally in
// English? Returns false for non-ASCII or words that don't start with
// a capital letter. The a/an rule follows pronunciation in English.
// We don't use the BBC's overcorrect "an historic occasion" though if
// you speak a dialect you may well say "an 'istoric occasion".
static bool AnWord(String* str) {
if (str->length() == 0) return false; // A nothing.
int c0 = str->Get(0);
int c1 = str->length() > 1 ? str->Get(1) : 0;
if (c0 == 'U') {
if (c1 > 'Z') {
return true; // An Umpire, but a UTF8String, a U.
}
} else if (c0 == 'A' || c0 == 'E' || c0 == 'I' || c0 == 'O') {
return true; // An Ape, an ABCBook.
} else if ((c1 == 0 || (c1 >= 'A' && c1 <= 'Z')) &&
(c0 == 'F' || c0 == 'H' || c0 == 'M' || c0 == 'N' || c0 == 'R' ||
c0 == 'S' || c0 == 'X')) {
return true; // An MP3File, an M.
}
return false;
}
MaybeObject* String::SlowTryFlatten(PretenureFlag pretenure) {
#ifdef DEBUG
// Do not attempt to flatten in debug mode when allocation is not
// allowed. This is to avoid an assertion failure when allocating.
// Flattening strings is the only case where we always allow
// allocation because no GC is performed if the allocation fails.
if (!HEAP->IsAllocationAllowed()) return this;
#endif
Heap* heap = GetHeap();
switch (StringShape(this).representation_tag()) {
case kConsStringTag: {
ConsString* cs = ConsString::cast(this);
if (cs->second()->length() == 0) {
return cs->first();
}
// There's little point in putting the flat string in new space if the
// cons string is in old space. It can never get GCed until there is
// an old space GC.
PretenureFlag tenure = heap->InNewSpace(this) ? pretenure : TENURED;
int len = length();
Object* object;
String* result;
if (IsAsciiRepresentation()) {
{ MaybeObject* maybe_object = heap->AllocateRawAsciiString(len, tenure);
if (!maybe_object->ToObject(&object)) return maybe_object;
}
result = String::cast(object);
String* first = cs->first();
int first_length = first->length();
char* dest = SeqAsciiString::cast(result)->GetChars();
WriteToFlat(first, dest, 0, first_length);
String* second = cs->second();
WriteToFlat(second,
dest + first_length,
0,
len - first_length);
} else {
{ MaybeObject* maybe_object =
heap->AllocateRawTwoByteString(len, tenure);
if (!maybe_object->ToObject(&object)) return maybe_object;
}
result = String::cast(object);
uc16* dest = SeqTwoByteString::cast(result)->GetChars();
String* first = cs->first();
int first_length = first->length();
WriteToFlat(first, dest, 0, first_length);
String* second = cs->second();
WriteToFlat(second,
dest + first_length,
0,
len - first_length);
}
cs->set_first(result);
cs->set_second(heap->empty_string(), SKIP_WRITE_BARRIER);
return result;
}
default:
return this;
}
}
bool String::MakeExternal(v8::String::ExternalStringResource* resource) {
// Externalizing twice leaks the external resource, so it's
// prohibited by the API.
ASSERT(!this->IsExternalString());
#ifdef DEBUG
if (FLAG_enable_slow_asserts) {
// Assert that the resource and the string are equivalent.
ASSERT(static_cast<size_t>(this->length()) == resource->length());
ScopedVector<uc16> smart_chars(this->length());
String::WriteToFlat(this, smart_chars.start(), 0, this->length());
ASSERT(memcmp(smart_chars.start(),
resource->data(),
resource->length() * sizeof(smart_chars[0])) == 0);
}
#endif // DEBUG
Heap* heap = GetHeap();
int size = this->Size(); // Byte size of the original string.
if (size < ExternalString::kShortSize) {
return false;
}
bool is_ascii = this->IsAsciiRepresentation();
bool is_symbol = this->IsSymbol();
// Morph the object to an external string by adjusting the map and
// reinitializing the fields.
if (size >= ExternalString::kSize) {
this->set_map_no_write_barrier(
is_symbol
? (is_ascii ? heap->external_symbol_with_ascii_data_map()
: heap->external_symbol_map())
: (is_ascii ? heap->external_string_with_ascii_data_map()
: heap->external_string_map()));
} else {
this->set_map_no_write_barrier(
is_symbol
? (is_ascii ? heap->short_external_symbol_with_ascii_data_map()
: heap->short_external_symbol_map())
: (is_ascii ? heap->short_external_string_with_ascii_data_map()
: heap->short_external_string_map()));
}
ExternalTwoByteString* self = ExternalTwoByteString::cast(this);
self->set_resource(resource);
if (is_symbol) self->Hash(); // Force regeneration of the hash value.
// Fill the remainder of the string with dead wood.
int new_size = this->Size(); // Byte size of the external String object.
heap->CreateFillerObjectAt(this->address() + new_size, size - new_size);
if (Marking::IsBlack(Marking::MarkBitFrom(this))) {
MemoryChunk::IncrementLiveBytesFromMutator(this->address(),
new_size - size);
}
return true;
}
bool String::MakeExternal(v8::String::ExternalAsciiStringResource* resource) {
#ifdef DEBUG
if (FLAG_enable_slow_asserts) {
// Assert that the resource and the string are equivalent.
ASSERT(static_cast<size_t>(this->length()) == resource->length());
ScopedVector<char> smart_chars(this->length());
String::WriteToFlat(this, smart_chars.start(), 0, this->length());
ASSERT(memcmp(smart_chars.start(),
resource->data(),
resource->length() * sizeof(smart_chars[0])) == 0);
}
#endif // DEBUG
Heap* heap = GetHeap();
int size = this->Size(); // Byte size of the original string.
if (size < ExternalString::kShortSize) {
return false;
}
bool is_symbol = this->IsSymbol();
// Morph the object to an external string by adjusting the map and
// reinitializing the fields. Use short version if space is limited.
if (size >= ExternalString::kSize) {
this->set_map_no_write_barrier(
is_symbol ? heap->external_ascii_symbol_map()
: heap->external_ascii_string_map());
} else {
this->set_map_no_write_barrier(
is_symbol ? heap->short_external_ascii_symbol_map()
: heap->short_external_ascii_string_map());
}
ExternalAsciiString* self = ExternalAsciiString::cast(this);
self->set_resource(resource);
if (is_symbol) self->Hash(); // Force regeneration of the hash value.
// Fill the remainder of the string with dead wood.
int new_size = this->Size(); // Byte size of the external String object.
heap->CreateFillerObjectAt(this->address() + new_size, size - new_size);
if (Marking::IsBlack(Marking::MarkBitFrom(this))) {
MemoryChunk::IncrementLiveBytesFromMutator(this->address(),
new_size - size);
}
return true;
}
void String::StringShortPrint(StringStream* accumulator) {
int len = length();
if (len > kMaxShortPrintLength) {
accumulator->Add("<Very long string[%u]>", len);
return;
}
if (!LooksValid()) {
accumulator->Add("<Invalid String>");
return;
}
StringInputBuffer buf(this);
bool truncated = false;
if (len > kMaxShortPrintLength) {
len = kMaxShortPrintLength;
truncated = true;
}
bool ascii = true;
for (int i = 0; i < len; i++) {
int c = buf.GetNext();
if (c < 32 || c >= 127) {
ascii = false;
}
}
buf.Reset(this);
if (ascii) {
accumulator->Add("<String[%u]: ", length());
for (int i = 0; i < len; i++) {
accumulator->Put(buf.GetNext());
}
accumulator->Put('>');
} else {
// Backslash indicates that the string contains control
// characters and that backslashes are therefore escaped.
accumulator->Add("<String[%u]\\: ", length());
for (int i = 0; i < len; i++) {
int c = buf.GetNext();
if (c == '\n') {
accumulator->Add("\\n");
} else if (c == '\r') {
accumulator->Add("\\r");
} else if (c == '\\') {
accumulator->Add("\\\\");
} else if (c < 32 || c > 126) {
accumulator->Add("\\x%02x", c);
} else {
accumulator->Put(c);
}
}
if (truncated) {
accumulator->Put('.');
accumulator->Put('.');
accumulator->Put('.');
}
accumulator->Put('>');
}
return;
}
void JSObject::JSObjectShortPrint(StringStream* accumulator) {
switch (map()->instance_type()) {
case JS_ARRAY_TYPE: {
double length = JSArray::cast(this)->length()->Number();
accumulator->Add("<JS Array[%u]>", static_cast<uint32_t>(length));
break;
}
case JS_WEAK_MAP_TYPE: {
accumulator->Add("<JS WeakMap>");
break;
}
case JS_REGEXP_TYPE: {
accumulator->Add("<JS RegExp>");
break;
}
case JS_FUNCTION_TYPE: {
Object* fun_name = JSFunction::cast(this)->shared()->name();
bool printed = false;
if (fun_name->IsString()) {
String* str = String::cast(fun_name);
if (str->length() > 0) {
accumulator->Add("<JS Function ");
accumulator->Put(str);
accumulator->Put('>');
printed = true;
}
}
if (!printed) {
accumulator->Add("<JS Function>");
}
break;
}
// All other JSObjects are rather similar to each other (JSObject,
// JSGlobalProxy, JSGlobalObject, JSUndetectableObject, JSValue).
default: {
Map* map_of_this = map();
Heap* heap = GetHeap();
Object* constructor = map_of_this->constructor();
bool printed = false;
if (constructor->IsHeapObject() &&
!heap->Contains(HeapObject::cast(constructor))) {
accumulator->Add("!!!INVALID CONSTRUCTOR!!!");
} else {
bool global_object = IsJSGlobalProxy();
if (constructor->IsJSFunction()) {
if (!heap->Contains(JSFunction::cast(constructor)->shared())) {
accumulator->Add("!!!INVALID SHARED ON CONSTRUCTOR!!!");
} else {
Object* constructor_name =
JSFunction::cast(constructor)->shared()->name();
if (constructor_name->IsString()) {
String* str = String::cast(constructor_name);
if (str->length() > 0) {
bool vowel = AnWord(str);
accumulator->Add("<%sa%s ",
global_object ? "Global Object: " : "",
vowel ? "n" : "");
accumulator->Put(str);
printed = true;
}
}
}
}
if (!printed) {
accumulator->Add("<JS %sObject", global_object ? "Global " : "");
}
}
if (IsJSValue()) {
accumulator->Add(" value = ");
JSValue::cast(this)->value()->ShortPrint(accumulator);
}
accumulator->Put('>');
break;
}
}
}
void JSObject::PrintElementsTransition(
FILE* file, ElementsKind from_kind, FixedArrayBase* from_elements,
ElementsKind to_kind, FixedArrayBase* to_elements) {
if (from_kind != to_kind) {
PrintF(file, "elements transition [");
PrintElementsKind(file, from_kind);
PrintF(file, " -> ");
PrintElementsKind(file, to_kind);
PrintF(file, "] in ");
JavaScriptFrame::PrintTop(file, false, true);
PrintF(file, " for ");
ShortPrint(file);
PrintF(file, " from ");
from_elements->ShortPrint(file);
PrintF(file, " to ");
to_elements->ShortPrint(file);
PrintF(file, "\n");
}
}
void HeapObject::HeapObjectShortPrint(StringStream* accumulator) {
Heap* heap = GetHeap();
if (!heap->Contains(this)) {
accumulator->Add("!!!INVALID POINTER!!!");
return;
}
if (!heap->Contains(map())) {
accumulator->Add("!!!INVALID MAP!!!");
return;
}
accumulator->Add("%p ", this);
if (IsString()) {
String::cast(this)->StringShortPrint(accumulator);
return;
}
if (IsJSObject()) {
JSObject::cast(this)->JSObjectShortPrint(accumulator);
return;
}
switch (map()->instance_type()) {
case MAP_TYPE:
accumulator->Add("<Map(elements=%u)>", Map::cast(this)->elements_kind());
break;
case FIXED_ARRAY_TYPE:
accumulator->Add("<FixedArray[%u]>", FixedArray::cast(this)->length());
break;
case FIXED_DOUBLE_ARRAY_TYPE:
accumulator->Add("<FixedDoubleArray[%u]>",
FixedDoubleArray::cast(this)->length());
break;
case BYTE_ARRAY_TYPE:
accumulator->Add("<ByteArray[%u]>", ByteArray::cast(this)->length());
break;
case FREE_SPACE_TYPE:
accumulator->Add("<FreeSpace[%u]>", FreeSpace::cast(this)->Size());
break;
case EXTERNAL_PIXEL_ARRAY_TYPE:
accumulator->Add("<ExternalPixelArray[%u]>",
ExternalPixelArray::cast(this)->length());
break;
case EXTERNAL_BYTE_ARRAY_TYPE:
accumulator->Add("<ExternalByteArray[%u]>",
ExternalByteArray::cast(this)->length());
break;
case EXTERNAL_UNSIGNED_BYTE_ARRAY_TYPE:
accumulator->Add("<ExternalUnsignedByteArray[%u]>",
ExternalUnsignedByteArray::cast(this)->length());
break;
case EXTERNAL_SHORT_ARRAY_TYPE:
accumulator->Add("<ExternalShortArray[%u]>",
ExternalShortArray::cast(this)->length());
break;
case EXTERNAL_UNSIGNED_SHORT_ARRAY_TYPE:
accumulator->Add("<ExternalUnsignedShortArray[%u]>",
ExternalUnsignedShortArray::cast(this)->length());
break;
case EXTERNAL_INT_ARRAY_TYPE:
accumulator->Add("<ExternalIntArray[%u]>",
ExternalIntArray::cast(this)->length());
break;
case EXTERNAL_UNSIGNED_INT_ARRAY_TYPE:
accumulator->Add("<ExternalUnsignedIntArray[%u]>",
ExternalUnsignedIntArray::cast(this)->length());
break;
case EXTERNAL_FLOAT_ARRAY_TYPE:
accumulator->Add("<ExternalFloatArray[%u]>",
ExternalFloatArray::cast(this)->length());
break;
case EXTERNAL_DOUBLE_ARRAY_TYPE:
accumulator->Add("<ExternalDoubleArray[%u]>",
ExternalDoubleArray::cast(this)->length());
break;
case SHARED_FUNCTION_INFO_TYPE:
accumulator->Add("<SharedFunctionInfo>");
break;
case JS_MESSAGE_OBJECT_TYPE:
accumulator->Add("<JSMessageObject>");
break;
#define MAKE_STRUCT_CASE(NAME, Name, name) \
case NAME##_TYPE: \
accumulator->Put('<'); \
accumulator->Add(#Name); \
accumulator->Put('>'); \
break;
STRUCT_LIST(MAKE_STRUCT_CASE)
#undef MAKE_STRUCT_CASE
case CODE_TYPE:
accumulator->Add("<Code>");
break;
case ODDBALL_TYPE: {
if (IsUndefined())
accumulator->Add("<undefined>");
else if (IsTheHole())
accumulator->Add("<the hole>");
else if (IsNull())
accumulator->Add("<null>");
else if (IsTrue())
accumulator->Add("<true>");
else if (IsFalse())
accumulator->Add("<false>");
else
accumulator->Add("<Odd Oddball>");
break;
}
case HEAP_NUMBER_TYPE:
accumulator->Add("<Number: ");
HeapNumber::cast(this)->HeapNumberPrint(accumulator);
accumulator->Put('>');
break;
case JS_PROXY_TYPE:
accumulator->Add("<JSProxy>");
break;
case JS_FUNCTION_PROXY_TYPE:
accumulator->Add("<JSFunctionProxy>");
break;
case FOREIGN_TYPE:
accumulator->Add("<Foreign>");
break;
case JS_GLOBAL_PROPERTY_CELL_TYPE:
accumulator->Add("Cell for ");
JSGlobalPropertyCell::cast(this)->value()->ShortPrint(accumulator);
break;
default:
accumulator->Add("<Other heap object (%d)>", map()->instance_type());
break;
}
}
void HeapObject::Iterate(ObjectVisitor* v) {
// Handle header
IteratePointer(v, kMapOffset);
// Handle object body
Map* m = map();
IterateBody(m->instance_type(), SizeFromMap(m), v);
}
void HeapObject::IterateBody(InstanceType type, int object_size,
ObjectVisitor* v) {
// Avoiding <Type>::cast(this) because it accesses the map pointer field.
// During GC, the map pointer field is encoded.
if (type < FIRST_NONSTRING_TYPE) {
switch (type & kStringRepresentationMask) {
case kSeqStringTag:
break;
case kConsStringTag:
ConsString::BodyDescriptor::IterateBody(this, v);
break;
case kSlicedStringTag:
SlicedString::BodyDescriptor::IterateBody(this, v);
break;
case kExternalStringTag:
if ((type & kStringEncodingMask) == kAsciiStringTag) {
reinterpret_cast<ExternalAsciiString*>(this)->
ExternalAsciiStringIterateBody(v);
} else {
reinterpret_cast<ExternalTwoByteString*>(this)->
ExternalTwoByteStringIterateBody(v);
}
break;
}
return;
}
switch (type) {
case FIXED_ARRAY_TYPE:
FixedArray::BodyDescriptor::IterateBody(this, object_size, v);
break;
case FIXED_DOUBLE_ARRAY_TYPE:
break;
case JS_OBJECT_TYPE:
case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
case JS_VALUE_TYPE:
case JS_DATE_TYPE:
case JS_ARRAY_TYPE:
case JS_SET_TYPE:
case JS_MAP_TYPE:
case JS_WEAK_MAP_TYPE:
case JS_REGEXP_TYPE:
case JS_GLOBAL_PROXY_TYPE:
case JS_GLOBAL_OBJECT_TYPE:
case JS_BUILTINS_OBJECT_TYPE:
case JS_MESSAGE_OBJECT_TYPE:
JSObject::BodyDescriptor::IterateBody(this, object_size, v);
break;
case JS_FUNCTION_TYPE:
reinterpret_cast<JSFunction*>(this)
->JSFunctionIterateBody(object_size, v);
break;
case ODDBALL_TYPE:
Oddball::BodyDescriptor::IterateBody(this, v);
break;
case JS_PROXY_TYPE:
JSProxy::BodyDescriptor::IterateBody(this, v);
break;
case JS_FUNCTION_PROXY_TYPE:
JSFunctionProxy::BodyDescriptor::IterateBody(this, v);
break;
case FOREIGN_TYPE:
reinterpret_cast<Foreign*>(this)->ForeignIterateBody(v);
break;
case MAP_TYPE:
Map::BodyDescriptor::IterateBody(this, v);
break;
case CODE_TYPE:
reinterpret_cast<Code*>(this)->CodeIterateBody(v);
break;
case JS_GLOBAL_PROPERTY_CELL_TYPE:
JSGlobalPropertyCell::BodyDescriptor::IterateBody(this, v);
break;
case HEAP_NUMBER_TYPE:
case FILLER_TYPE:
case BYTE_ARRAY_TYPE:
case FREE_SPACE_TYPE:
case EXTERNAL_PIXEL_ARRAY_TYPE:
case EXTERNAL_BYTE_ARRAY_TYPE:
case EXTERNAL_UNSIGNED_BYTE_ARRAY_TYPE:
case EXTERNAL_SHORT_ARRAY_TYPE:
case EXTERNAL_UNSIGNED_SHORT_ARRAY_TYPE:
case EXTERNAL_INT_ARRAY_TYPE:
case EXTERNAL_UNSIGNED_INT_ARRAY_TYPE:
case EXTERNAL_FLOAT_ARRAY_TYPE:
case EXTERNAL_DOUBLE_ARRAY_TYPE:
break;
case SHARED_FUNCTION_INFO_TYPE: {
SharedFunctionInfo* shared = reinterpret_cast<SharedFunctionInfo*>(this);
shared->SharedFunctionInfoIterateBody(v);
break;
}
#define MAKE_STRUCT_CASE(NAME, Name, name) \
case NAME##_TYPE:
STRUCT_LIST(MAKE_STRUCT_CASE)
#undef MAKE_STRUCT_CASE
StructBodyDescriptor::IterateBody(this, object_size, v);
break;
default:
PrintF("Unknown type: %d\n", type);
UNREACHABLE();
}
}
Object* HeapNumber::HeapNumberToBoolean() {
// NaN, +0, and -0 should return the false object
#if __BYTE_ORDER == __LITTLE_ENDIAN
union IeeeDoubleLittleEndianArchType u;
#elif __BYTE_ORDER == __BIG_ENDIAN
union IeeeDoubleBigEndianArchType u;
#endif
u.d = value();
if (u.bits.exp == 2047) {
// Detect NaN for IEEE double precision floating point.
if ((u.bits.man_low | u.bits.man_high) != 0)
return GetHeap()->false_value();
}
if (u.bits.exp == 0) {
// Detect +0, and -0 for IEEE double precision floating point.
if ((u.bits.man_low | u.bits.man_high) == 0)
return GetHeap()->false_value();
}
return GetHeap()->true_value();
}
void HeapNumber::HeapNumberPrint(FILE* out) {
PrintF(out, "%.16g", Number());
}
void HeapNumber::HeapNumberPrint(StringStream* accumulator) {
// The Windows version of vsnprintf can allocate when printing a %g string
// into a buffer that may not be big enough. We don't want random memory
// allocation when producing post-crash stack traces, so we print into a
// buffer that is plenty big enough for any floating point number, then
// print that using vsnprintf (which may truncate but never allocate if
// there is no more space in the buffer).
EmbeddedVector<char, 100> buffer;
OS::SNPrintF(buffer, "%.16g", Number());
accumulator->Add("%s", buffer.start());
}
String* JSReceiver::class_name() {
if (IsJSFunction() && IsJSFunctionProxy()) {
return GetHeap()->function_class_symbol();
}
if (map()->constructor()->IsJSFunction()) {
JSFunction* constructor = JSFunction::cast(map()->constructor());
return String::cast(constructor->shared()->instance_class_name());
}
// If the constructor is not present, return "Object".
return GetHeap()->Object_symbol();
}
String* JSReceiver::constructor_name() {
if (map()->constructor()->IsJSFunction()) {
JSFunction* constructor = JSFunction::cast(map()->constructor());
String* name = String::cast(constructor->shared()->name());
if (name->length() > 0) return name;
String* inferred_name = constructor->shared()->inferred_name();
if (inferred_name->length() > 0) return inferred_name;
Object* proto = GetPrototype();
if (proto->IsJSObject()) return JSObject::cast(proto)->constructor_name();
}
// TODO(rossberg): what about proxies?
// If the constructor is not present, return "Object".
return GetHeap()->Object_symbol();
}
MaybeObject* JSObject::AddFastPropertyUsingMap(Map* new_map,
String* name,
Object* value) {
int index = new_map->PropertyIndexFor(name);
if (map()->unused_property_fields() == 0) {
ASSERT(map()->unused_property_fields() == 0);
int new_unused = new_map->unused_property_fields();
Object* values;
{ MaybeObject* maybe_values =
properties()->CopySize(properties()->length() + new_unused + 1);
if (!maybe_values->ToObject(&values)) return maybe_values;
}
set_properties(FixedArray::cast(values));
}
set_map(new_map);
return FastPropertyAtPut(index, value);
}
static bool IsIdentifier(UnicodeCache* cache,
unibrow::CharacterStream* buffer) {
// Checks whether the buffer contains an identifier (no escape).
if (!buffer->has_more()) return false;
if (!cache->IsIdentifierStart(buffer->GetNext())) {
return false;
}
while (buffer->has_more()) {
if (!cache->IsIdentifierPart(buffer->GetNext())) {
return false;
}
}
return true;
}
MaybeObject* JSObject::AddFastProperty(String* name,
Object* value,
PropertyAttributes attributes) {
ASSERT(!IsJSGlobalProxy());
// Normalize the object if the name is an actual string (not the
// hidden symbols) and is not a real identifier.
Isolate* isolate = GetHeap()->isolate();
StringInputBuffer buffer(name);
if (!IsIdentifier(isolate->unicode_cache(), &buffer)
&& name != isolate->heap()->hidden_symbol()) {
Object* obj;
{ MaybeObject* maybe_obj =
NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return AddSlowProperty(name, value, attributes);
}
DescriptorArray* old_descriptors = map()->instance_descriptors();
// Compute the new index for new field.
int index = map()->NextFreePropertyIndex();
// Allocate new instance descriptors with (name, index) added
FieldDescriptor new_field(name, index, attributes);
Object* new_descriptors;
{ MaybeObject* maybe_new_descriptors =
old_descriptors->CopyInsert(&new_field, REMOVE_TRANSITIONS);
if (!maybe_new_descriptors->ToObject(&new_descriptors)) {
return maybe_new_descriptors;
}
}
// Only allow map transition if the object isn't the global object and there
// is not a transition for the name, or there's a transition for the name but
// it's unrelated to properties.
int descriptor_index = old_descriptors->Search(name);
// Element transitions are stored in the descriptor for property "", which is
// not a identifier and should have forced a switch to slow properties above.
ASSERT(descriptor_index == DescriptorArray::kNotFound ||
old_descriptors->GetType(descriptor_index) != ELEMENTS_TRANSITION);
bool can_insert_transition = descriptor_index == DescriptorArray::kNotFound ||
old_descriptors->GetType(descriptor_index) == ELEMENTS_TRANSITION;
bool allow_map_transition =
can_insert_transition &&
(isolate->context()->global_context()->object_function()->map() != map());
ASSERT(index < map()->inobject_properties() ||
(index - map()->inobject_properties()) < properties()->length() ||
map()->unused_property_fields() == 0);
// Allocate a new map for the object.
Object* r;
{ MaybeObject* maybe_r = map()->CopyDropDescriptors();
if (!maybe_r->ToObject(&r)) return maybe_r;
}
Map* new_map = Map::cast(r);
if (allow_map_transition) {
// Allocate new instance descriptors for the old map with map transition.
MapTransitionDescriptor d(name, Map::cast(new_map), attributes);
Object* r;
{ MaybeObject* maybe_r = old_descriptors->CopyInsert(&d, KEEP_TRANSITIONS);
if (!maybe_r->ToObject(&r)) return maybe_r;
}
old_descriptors = DescriptorArray::cast(r);
}
if (map()->unused_property_fields() == 0) {
if (properties()->length() > MaxFastProperties()) {
Object* obj;
{ MaybeObject* maybe_obj =
NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return AddSlowProperty(name, value, attributes);
}
// Make room for the new value
Object* values;
{ MaybeObject* maybe_values =
properties()->CopySize(properties()->length() + kFieldsAdded);
if (!maybe_values->ToObject(&values)) return maybe_values;
}
set_properties(FixedArray::cast(values));
new_map->set_unused_property_fields(kFieldsAdded - 1);
} else {
new_map->set_unused_property_fields(map()->unused_property_fields() - 1);
}
// We have now allocated all the necessary objects.
// All the changes can be applied at once, so they are atomic.
map()->set_instance_descriptors(old_descriptors);
new_map->set_instance_descriptors(DescriptorArray::cast(new_descriptors));
set_map(new_map);
return FastPropertyAtPut(index, value);
}
MaybeObject* JSObject::AddConstantFunctionProperty(
String* name,
JSFunction* function,
PropertyAttributes attributes) {
// Allocate new instance descriptors with (name, function) added
ConstantFunctionDescriptor d(name, function, attributes);
Object* new_descriptors;
{ MaybeObject* maybe_new_descriptors =
map()->instance_descriptors()->CopyInsert(&d, REMOVE_TRANSITIONS);
if (!maybe_new_descriptors->ToObject(&new_descriptors)) {
return maybe_new_descriptors;
}
}
// Allocate a new map for the object.
Object* new_map;
{ MaybeObject* maybe_new_map = map()->CopyDropDescriptors();
if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
}
DescriptorArray* descriptors = DescriptorArray::cast(new_descriptors);
Map::cast(new_map)->set_instance_descriptors(descriptors);
Map* old_map = map();
set_map(Map::cast(new_map));
// If the old map is the global object map (from new Object()),
// then transitions are not added to it, so we are done.
Heap* heap = GetHeap();
if (old_map == heap->isolate()->context()->global_context()->
object_function()->map()) {
return function;
}
// Do not add CONSTANT_TRANSITIONS to global objects
if (IsGlobalObject()) {
return function;
}
// Add a CONSTANT_TRANSITION descriptor to the old map,
// so future assignments to this property on other objects
// of the same type will create a normal field, not a constant function.
// Don't do this for special properties, with non-trival attributes.
if (attributes != NONE) {
return function;
}
ConstTransitionDescriptor mark(name, Map::cast(new_map));
{ MaybeObject* maybe_new_descriptors =
old_map->instance_descriptors()->CopyInsert(&mark, KEEP_TRANSITIONS);
if (!maybe_new_descriptors->ToObject(&new_descriptors)) {
// We have accomplished the main goal, so return success.
return function;
}
}
old_map->set_instance_descriptors(DescriptorArray::cast(new_descriptors));
return function;
}
// Add property in slow mode
MaybeObject* JSObject::AddSlowProperty(String* name,
Object* value,
PropertyAttributes attributes) {
ASSERT(!HasFastProperties());
StringDictionary* dict = property_dictionary();
Object* store_value = value;
if (IsGlobalObject()) {
// In case name is an orphaned property reuse the cell.
int entry = dict->FindEntry(name);
if (entry != StringDictionary::kNotFound) {
store_value = dict->ValueAt(entry);
JSGlobalPropertyCell::cast(store_value)->set_value(value);
// Assign an enumeration index to the property and update
// SetNextEnumerationIndex.
int index = dict->NextEnumerationIndex();
PropertyDetails details = PropertyDetails(attributes, NORMAL, index);
dict->SetNextEnumerationIndex(index + 1);
dict->SetEntry(entry, name, store_value, details);
return value;
}
Heap* heap = GetHeap();
{ MaybeObject* maybe_store_value =
heap->AllocateJSGlobalPropertyCell(value);
if (!maybe_store_value->ToObject(&store_value)) return maybe_store_value;
}
JSGlobalPropertyCell::cast(store_value)->set_value(value);
}
PropertyDetails details = PropertyDetails(attributes, NORMAL);
Object* result;
{ MaybeObject* maybe_result = dict->Add(name, store_value, details);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
if (dict != result) set_properties(StringDictionary::cast(result));
return value;
}
MaybeObject* JSObject::AddProperty(String* name,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
ASSERT(!IsJSGlobalProxy());
Map* map_of_this = map();
Heap* heap = GetHeap();
if (!map_of_this->is_extensible()) {
if (strict_mode == kNonStrictMode) {
return value;
} else {
Handle<Object> args[1] = {Handle<String>(name)};
return heap->isolate()->Throw(
*FACTORY->NewTypeError("object_not_extensible",
HandleVector(args, 1)));
}
}
if (HasFastProperties()) {
// Ensure the descriptor array does not get too big.
if (map_of_this->instance_descriptors()->number_of_descriptors() <
DescriptorArray::kMaxNumberOfDescriptors) {
if (value->IsJSFunction()) {
return AddConstantFunctionProperty(name,
JSFunction::cast(value),
attributes);
} else {
return AddFastProperty(name, value, attributes);
}
} else {
// Normalize the object to prevent very large instance descriptors.
// This eliminates unwanted N^2 allocation and lookup behavior.
Object* obj;
{ MaybeObject* maybe_obj =
NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
}
}
return AddSlowProperty(name, value, attributes);
}
MaybeObject* JSObject::SetPropertyPostInterceptor(
String* name,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
// Check local property, ignore interceptor.
LookupResult result(GetIsolate());
LocalLookupRealNamedProperty(name, &result);
if (result.IsFound()) {
// An existing property, a map transition or a null descriptor was
// found. Use set property to handle all these cases.
return SetProperty(&result, name, value, attributes, strict_mode);
}
bool found = false;
MaybeObject* result_object;
result_object = SetPropertyWithCallbackSetterInPrototypes(name,
value,
attributes,
&found,
strict_mode);
if (found) return result_object;
// Add a new real property.
return AddProperty(name, value, attributes, strict_mode);
}
MaybeObject* JSObject::ReplaceSlowProperty(String* name,
Object* value,
PropertyAttributes attributes) {
StringDictionary* dictionary = property_dictionary();
int old_index = dictionary->FindEntry(name);
int new_enumeration_index = 0; // 0 means "Use the next available index."
if (old_index != -1) {
// All calls to ReplaceSlowProperty have had all transitions removed.
ASSERT(!dictionary->ContainsTransition(old_index));
new_enumeration_index = dictionary->DetailsAt(old_index).index();
}
PropertyDetails new_details(attributes, NORMAL, new_enumeration_index);
return SetNormalizedProperty(name, value, new_details);
}
MaybeObject* JSObject::ConvertDescriptorToFieldAndMapTransition(
String* name,
Object* new_value,
PropertyAttributes attributes) {
Map* old_map = map();
Object* result;
{ MaybeObject* maybe_result =
ConvertDescriptorToField(name, new_value, attributes);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
// If we get to this point we have succeeded - do not return failure
// after this point. Later stuff is optional.
if (!HasFastProperties()) {
return result;
}
// Do not add transitions to the map of "new Object()".
if (map() == GetIsolate()->context()->global_context()->
object_function()->map()) {
return result;
}
MapTransitionDescriptor transition(name,
map(),
attributes);
Object* new_descriptors;
{ MaybeObject* maybe_new_descriptors = old_map->instance_descriptors()->
CopyInsert(&transition, KEEP_TRANSITIONS);
if (!maybe_new_descriptors->ToObject(&new_descriptors)) {
return result; // Yes, return _result_.
}
}
old_map->set_instance_descriptors(DescriptorArray::cast(new_descriptors));
return result;
}
MaybeObject* JSObject::ConvertDescriptorToField(String* name,
Object* new_value,
PropertyAttributes attributes) {
if (map()->unused_property_fields() == 0 &&
properties()->length() > MaxFastProperties()) {
Object* obj;
{ MaybeObject* maybe_obj =
NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return ReplaceSlowProperty(name, new_value, attributes);
}
int index = map()->NextFreePropertyIndex();
FieldDescriptor new_field(name, index, attributes);
// Make a new DescriptorArray replacing an entry with FieldDescriptor.
Object* descriptors_unchecked;
{ MaybeObject* maybe_descriptors_unchecked = map()->instance_descriptors()->
CopyInsert(&new_field, REMOVE_TRANSITIONS);
if (!maybe_descriptors_unchecked->ToObject(&descriptors_unchecked)) {
return maybe_descriptors_unchecked;
}
}
DescriptorArray* new_descriptors =
DescriptorArray::cast(descriptors_unchecked);
// Make a new map for the object.
Object* new_map_unchecked;
{ MaybeObject* maybe_new_map_unchecked = map()->CopyDropDescriptors();
if (!maybe_new_map_unchecked->ToObject(&new_map_unchecked)) {
return maybe_new_map_unchecked;
}
}
Map* new_map = Map::cast(new_map_unchecked);
new_map->set_instance_descriptors(new_descriptors);
// Make new properties array if necessary.
FixedArray* new_properties = 0; // Will always be NULL or a valid pointer.
int new_unused_property_fields = map()->unused_property_fields() - 1;
if (map()->unused_property_fields() == 0) {
new_unused_property_fields = kFieldsAdded - 1;
Object* new_properties_object;
{ MaybeObject* maybe_new_properties_object =
properties()->CopySize(properties()->length() + kFieldsAdded);
if (!maybe_new_properties_object->ToObject(&new_properties_object)) {
return maybe_new_properties_object;
}
}
new_properties = FixedArray::cast(new_properties_object);
}
// Update pointers to commit changes.
// Object points to the new map.
new_map->set_unused_property_fields(new_unused_property_fields);
set_map(new_map);
if (new_properties) {
set_properties(FixedArray::cast(new_properties));
}
return FastPropertyAtPut(index, new_value);
}
MaybeObject* JSObject::SetPropertyWithInterceptor(
String* name,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<JSObject> this_handle(this);
Handle<String> name_handle(name);
Handle<Object> value_handle(value, isolate);
Handle<InterceptorInfo> interceptor(GetNamedInterceptor());
if (!interceptor->setter()->IsUndefined()) {
LOG(isolate, ApiNamedPropertyAccess("interceptor-named-set", this, name));
CustomArguments args(isolate, interceptor->data(), this, this);
v8::AccessorInfo info(args.end());
v8::NamedPropertySetter setter =
v8::ToCData<v8::NamedPropertySetter>(interceptor->setter());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
Handle<Object> value_unhole(value->IsTheHole() ?
isolate->heap()->undefined_value() :
value,
isolate);
result = setter(v8::Utils::ToLocal(name_handle),
v8::Utils::ToLocal(value_unhole),
info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) return *value_handle;
}
MaybeObject* raw_result =
this_handle->SetPropertyPostInterceptor(*name_handle,
*value_handle,
attributes,
strict_mode);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return raw_result;
}
Handle<Object> JSReceiver::SetProperty(Handle<JSReceiver> object,
Handle<String> key,
Handle<Object> value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
CALL_HEAP_FUNCTION(object->GetIsolate(),
object->SetProperty(*key, *value, attributes, strict_mode),
Object);
}
MaybeObject* JSReceiver::SetProperty(String* name,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
LookupResult result(GetIsolate());
LocalLookup(name, &result);
return SetProperty(&result, name, value, attributes, strict_mode);
}
MaybeObject* JSObject::SetPropertyWithCallback(Object* structure,
String* name,
Object* value,
JSObject* holder,
StrictModeFlag strict_mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
// We should never get here to initialize a const with the hole
// value since a const declaration would conflict with the setter.
ASSERT(!value->IsTheHole());
Handle<Object> value_handle(value, isolate);
// To accommodate both the old and the new api we switch on the
// data structure used to store the callbacks. Eventually foreign
// callbacks should be phased out.
if (structure->IsForeign()) {
AccessorDescriptor* callback =
reinterpret_cast<AccessorDescriptor*>(
Foreign::cast(structure)->foreign_address());
MaybeObject* obj = (callback->setter)(this, value, callback->data);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (obj->IsFailure()) return obj;
return *value_handle;
}
if (structure->IsAccessorInfo()) {
// api style callbacks
AccessorInfo* data = AccessorInfo::cast(structure);
Object* call_obj = data->setter();
v8::AccessorSetter call_fun = v8::ToCData<v8::AccessorSetter>(call_obj);
if (call_fun == NULL) return value;
Handle<String> key(name);
LOG(isolate, ApiNamedPropertyAccess("store", this, name));
CustomArguments args(isolate, data->data(), this, JSObject::cast(holder));
v8::AccessorInfo info(args.end());
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
call_fun(v8::Utils::ToLocal(key),
v8::Utils::ToLocal(value_handle),
info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return *value_handle;
}
if (structure->IsAccessorPair()) {
Object* setter = AccessorPair::cast(structure)->setter();
if (setter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return SetPropertyWithDefinedSetter(JSReceiver::cast(setter), value);
} else {
if (strict_mode == kNonStrictMode) {
return value;
}
Handle<String> key(name);
Handle<Object> holder_handle(holder, isolate);
Handle<Object> args[2] = { key, holder_handle };
return isolate->Throw(
*isolate->factory()->NewTypeError("no_setter_in_callback",
HandleVector(args, 2)));
}
}
UNREACHABLE();
return NULL;
}
MaybeObject* JSReceiver::SetPropertyWithDefinedSetter(JSReceiver* setter,
Object* value) {
Isolate* isolate = GetIsolate();
Handle<Object> value_handle(value, isolate);
Handle<JSReceiver> fun(setter, isolate);
Handle<JSReceiver> self(this, isolate);
#ifdef ENABLE_DEBUGGER_SUPPORT
Debug* debug = isolate->debug();
// Handle stepping into a setter if step into is active.
// TODO(rossberg): should this apply to getters that are function proxies?
if (debug->StepInActive() && fun->IsJSFunction()) {
debug->HandleStepIn(
Handle<JSFunction>::cast(fun), Handle<Object>::null(), 0, false);
}
#endif
bool has_pending_exception;
Handle<Object> argv[] = { value_handle };
Execution::Call(fun, self, ARRAY_SIZE(argv), argv, &has_pending_exception);
// Check for pending exception and return the result.
if (has_pending_exception) return Failure::Exception();
return *value_handle;
}
void JSObject::LookupCallbackSetterInPrototypes(String* name,
LookupResult* result) {
Heap* heap = GetHeap();
for (Object* pt = GetPrototype();
pt != heap->null_value();
pt = pt->GetPrototype()) {
if (pt->IsJSProxy()) {
return result->HandlerResult(JSProxy::cast(pt));
}
JSObject::cast(pt)->LocalLookupRealNamedProperty(name, result);
if (result->IsProperty()) {
if (result->type() == CALLBACKS && !result->IsReadOnly()) return;
// Found non-callback or read-only callback, stop looking.
break;
}
}
result->NotFound();
}
MaybeObject* JSObject::SetElementWithCallbackSetterInPrototypes(
uint32_t index,
Object* value,
bool* found,
StrictModeFlag strict_mode) {
Heap* heap = GetHeap();
for (Object* pt = GetPrototype();
pt != heap->null_value();
pt = pt->GetPrototype()) {
if (pt->IsJSProxy()) {
String* name;
MaybeObject* maybe = GetHeap()->Uint32ToString(index);
if (!maybe->To<String>(&name)) {
*found = true; // Force abort
return maybe;
}
return JSProxy::cast(pt)->SetPropertyWithHandlerIfDefiningSetter(
name, value, NONE, strict_mode, found);
}
if (!JSObject::cast(pt)->HasDictionaryElements()) {
continue;
}
SeededNumberDictionary* dictionary =
JSObject::cast(pt)->element_dictionary();
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS) {
*found = true;
return SetElementWithCallback(dictionary->ValueAt(entry),
index,
value,
JSObject::cast(pt),
strict_mode);
}
}
}
*found = false;
return heap->the_hole_value();
}
MaybeObject* JSObject::SetPropertyWithCallbackSetterInPrototypes(
String* name,
Object* value,
PropertyAttributes attributes,
bool* found,
StrictModeFlag strict_mode) {
Heap* heap = GetHeap();
// We could not find a local property so let's check whether there is an
// accessor that wants to handle the property.
LookupResult accessor_result(heap->isolate());
LookupCallbackSetterInPrototypes(name, &accessor_result);
if (accessor_result.IsFound()) {
*found = true;
if (accessor_result.type() == CALLBACKS) {
return SetPropertyWithCallback(accessor_result.GetCallbackObject(),
name,
value,
accessor_result.holder(),
strict_mode);
} else if (accessor_result.type() == HANDLER) {
// There is a proxy in the prototype chain. Invoke its
// getPropertyDescriptor trap.
bool found = false;
// SetPropertyWithHandlerIfDefiningSetter can cause GC,
// make sure to use the handlified references after calling
// the function.
Handle<JSObject> self(this);
Handle<String> hname(name);
Handle<Object> hvalue(value);
MaybeObject* result =
accessor_result.proxy()->SetPropertyWithHandlerIfDefiningSetter(
name, value, attributes, strict_mode, &found);
if (found) return result;
// The proxy does not define the property as an accessor.
// Consequently, it has no effect on setting the receiver.
return self->AddProperty(*hname, *hvalue, attributes, strict_mode);
}
}
*found = false;
return heap->the_hole_value();
}
void JSObject::LookupInDescriptor(String* name, LookupResult* result) {
DescriptorArray* descriptors = map()->instance_descriptors();
int number = descriptors->SearchWithCache(name);
if (number != DescriptorArray::kNotFound) {
result->DescriptorResult(this, descriptors->GetDetails(number), number);
} else {
result->NotFound();
}
}
void Map::LookupInDescriptors(JSObject* holder,
String* name,
LookupResult* result) {
DescriptorArray* descriptors = instance_descriptors();
DescriptorLookupCache* cache =
GetHeap()->isolate()->descriptor_lookup_cache();
int number = cache->Lookup(descriptors, name);
if (number == DescriptorLookupCache::kAbsent) {
number = descriptors->Search(name);
cache->Update(descriptors, name, number);
}
if (number != DescriptorArray::kNotFound) {
result->DescriptorResult(holder, descriptors->GetDetails(number), number);
} else {
result->NotFound();
}
}
static bool ContainsMap(MapHandleList* maps, Handle<Map> map) {
ASSERT(!map.is_null());
for (int i = 0; i < maps->length(); ++i) {
if (!maps->at(i).is_null() && maps->at(i).is_identical_to(map)) return true;
}
return false;
}
template <class T>
static Handle<T> MaybeNull(T* p) {
if (p == NULL) return Handle<T>::null();
return Handle<T>(p);
}
Handle<Map> Map::FindTransitionedMap(MapHandleList* candidates) {
ElementsKind elms_kind = elements_kind();
if (elms_kind == FAST_DOUBLE_ELEMENTS) {
bool dummy = true;
Handle<Map> fast_map =
MaybeNull(LookupElementsTransitionMap(FAST_ELEMENTS, &dummy));
if (!fast_map.is_null() && ContainsMap(candidates, fast_map)) {
return fast_map;
}
return Handle<Map>::null();
}
if (elms_kind == FAST_SMI_ONLY_ELEMENTS) {
bool dummy = true;
Handle<Map> double_map =
MaybeNull(LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS, &dummy));
// In the current implementation, if the DOUBLE map doesn't exist, the
// FAST map can't exist either.
if (double_map.is_null()) return Handle<Map>::null();
Handle<Map> fast_map =
MaybeNull(double_map->LookupElementsTransitionMap(FAST_ELEMENTS,
&dummy));
if (!fast_map.is_null() && ContainsMap(candidates, fast_map)) {
return fast_map;
}
if (ContainsMap(candidates, double_map)) return double_map;
}
return Handle<Map>::null();
}
static Map* GetElementsTransitionMapFromDescriptor(Object* descriptor_contents,
ElementsKind elements_kind) {
if (descriptor_contents->IsMap()) {
Map* map = Map::cast(descriptor_contents);
if (map->elements_kind() == elements_kind) {
return map;
}
return NULL;
}
FixedArray* map_array = FixedArray::cast(descriptor_contents);
for (int i = 0; i < map_array->length(); ++i) {
Object* current = map_array->get(i);
// Skip undefined slots, they are sentinels for reclaimed maps.
if (!current->IsUndefined()) {
Map* current_map = Map::cast(map_array->get(i));
if (current_map->elements_kind() == elements_kind) {
return current_map;
}
}
}
return NULL;
}
static MaybeObject* AddElementsTransitionMapToDescriptor(
Object* descriptor_contents,
Map* new_map) {
// Nothing was in the descriptor for an ELEMENTS_TRANSITION,
// simply add the map.
if (descriptor_contents == NULL) {
return new_map;
}
// There was already a map in the descriptor, create a 2-element FixedArray
// to contain the existing map plus the new one.
FixedArray* new_array;
Heap* heap = new_map->GetHeap();
if (descriptor_contents->IsMap()) {
// Must tenure, DescriptorArray expects no new-space objects.
MaybeObject* maybe_new_array = heap->AllocateFixedArray(2, TENURED);
if (!maybe_new_array->To<FixedArray>(&new_array)) {
return maybe_new_array;
}
new_array->set(0, descriptor_contents);
new_array->set(1, new_map);
return new_array;
}
// The descriptor already contained a list of maps for different ElementKinds
// of ELEMENTS_TRANSITION, first check the existing array for an undefined
// slot, and if that's not available, create a FixedArray to hold the existing
// maps plus the new one and fill it in.
FixedArray* array = FixedArray::cast(descriptor_contents);
for (int i = 0; i < array->length(); ++i) {
if (array->get(i)->IsUndefined()) {
array->set(i, new_map);
return array;
}
}
// Must tenure, DescriptorArray expects no new-space objects.
MaybeObject* maybe_new_array =
heap->AllocateFixedArray(array->length() + 1, TENURED);
if (!maybe_new_array->To<FixedArray>(&new_array)) {
return maybe_new_array;
}
int i = 0;
while (i < array->length()) {
new_array->set(i, array->get(i));
++i;
}
new_array->set(i, new_map);
return new_array;
}
String* Map::elements_transition_sentinel_name() {
return GetHeap()->empty_symbol();
}
Object* Map::GetDescriptorContents(String* sentinel_name,
bool* safe_to_add_transition) {
// Get the cached index for the descriptors lookup, or find and cache it.
DescriptorArray* descriptors = instance_descriptors();
DescriptorLookupCache* cache = GetIsolate()->descriptor_lookup_cache();
int index = cache->Lookup(descriptors, sentinel_name);
if (index == DescriptorLookupCache::kAbsent) {
index = descriptors->Search(sentinel_name);
cache->Update(descriptors, sentinel_name, index);
}
// If the transition already exists, return its descriptor.
if (index != DescriptorArray::kNotFound) {
PropertyDetails details(descriptors->GetDetails(index));
if (details.type() == ELEMENTS_TRANSITION) {
return descriptors->GetValue(index);
} else {
if (safe_to_add_transition != NULL) {
*safe_to_add_transition = false;
}
}
}
return NULL;
}
Map* Map::LookupElementsTransitionMap(ElementsKind elements_kind,
bool* safe_to_add_transition) {
// Special case: indirect SMI->FAST transition (cf. comment in
// AddElementsTransition()).
if (this->elements_kind() == FAST_SMI_ONLY_ELEMENTS &&
elements_kind == FAST_ELEMENTS) {
Map* double_map = this->LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS,
safe_to_add_transition);
if (double_map == NULL) return double_map;
return double_map->LookupElementsTransitionMap(FAST_ELEMENTS,
safe_to_add_transition);
}
Object* descriptor_contents = GetDescriptorContents(
elements_transition_sentinel_name(), safe_to_add_transition);
if (descriptor_contents != NULL) {
Map* maybe_transition_map =
GetElementsTransitionMapFromDescriptor(descriptor_contents,
elements_kind);
ASSERT(maybe_transition_map == NULL || maybe_transition_map->IsMap());
return maybe_transition_map;
}
return NULL;
}
MaybeObject* Map::AddElementsTransition(ElementsKind elements_kind,
Map* transitioned_map) {
// The map transition graph should be a tree, therefore the transition
// from SMI to FAST elements is not done directly, but by going through
// DOUBLE elements first.
if (this->elements_kind() == FAST_SMI_ONLY_ELEMENTS &&
elements_kind == FAST_ELEMENTS) {
bool safe_to_add = true;
Map* double_map = this->LookupElementsTransitionMap(
FAST_DOUBLE_ELEMENTS, &safe_to_add);
// This method is only called when safe_to_add_transition has been found
// to be true earlier.
ASSERT(safe_to_add);
if (double_map == NULL) {
MaybeObject* maybe_map = this->CopyDropTransitions();
if (!maybe_map->To(&double_map)) return maybe_map;
double_map->set_elements_kind(FAST_DOUBLE_ELEMENTS);
MaybeObject* maybe_double_transition = this->AddElementsTransition(
FAST_DOUBLE_ELEMENTS, double_map);
if (maybe_double_transition->IsFailure()) return maybe_double_transition;
}
return double_map->AddElementsTransition(FAST_ELEMENTS, transitioned_map);
}
bool safe_to_add_transition = true;
Object* descriptor_contents = GetDescriptorContents(
elements_transition_sentinel_name(), &safe_to_add_transition);
// This method is only called when safe_to_add_transition has been found
// to be true earlier.
ASSERT(safe_to_add_transition);
MaybeObject* maybe_new_contents =
AddElementsTransitionMapToDescriptor(descriptor_contents,
transitioned_map);
Object* new_contents;
if (!maybe_new_contents->ToObject(&new_contents)) {
return maybe_new_contents;
}
ElementsTransitionDescriptor desc(elements_transition_sentinel_name(),
new_contents);
Object* new_descriptors;
MaybeObject* maybe_new_descriptors =
instance_descriptors()->CopyInsert(&desc, KEEP_TRANSITIONS);
if (!maybe_new_descriptors->ToObject(&new_descriptors)) {
return maybe_new_descriptors;
}
set_instance_descriptors(DescriptorArray::cast(new_descriptors));
return this;
}
Handle<Map> JSObject::GetElementsTransitionMap(Handle<JSObject> object,
ElementsKind to_kind) {
Isolate* isolate = object->GetIsolate();
CALL_HEAP_FUNCTION(isolate,
object->GetElementsTransitionMap(isolate, to_kind),
Map);
}
MaybeObject* JSObject::GetElementsTransitionMapSlow(ElementsKind to_kind) {
Map* current_map = map();
ElementsKind from_kind = current_map->elements_kind();
if (from_kind == to_kind) return current_map;
// Only objects with FastProperties can have DescriptorArrays and can track
// element-related maps. Also don't add descriptors to maps that are shared.
bool safe_to_add_transition = HasFastProperties() &&
!current_map->IsUndefined() &&
!current_map->is_shared();
// Prevent long chains of DICTIONARY -> FAST_ELEMENTS maps caused by objects
// with elements that switch back and forth between dictionary and fast
// element mode.
if (from_kind == DICTIONARY_ELEMENTS && to_kind == FAST_ELEMENTS) {
safe_to_add_transition = false;
}
if (safe_to_add_transition) {
// It's only safe to manipulate the descriptor array if it would be
// safe to add a transition.
Map* maybe_transition_map = current_map->LookupElementsTransitionMap(
to_kind, &safe_to_add_transition);
if (maybe_transition_map != NULL) {
return maybe_transition_map;
}
}
Map* new_map = NULL;
// No transition to an existing map for the given ElementsKind. Make a new
// one.
{ MaybeObject* maybe_map = current_map->CopyDropTransitions();
if (!maybe_map->To(&new_map)) return maybe_map;
}
new_map->set_elements_kind(to_kind);
// Only remember the map transition if the object's map is NOT equal to the
// global object_function's map and there is not an already existing
// non-matching element transition.
Context* global_context = GetIsolate()->context()->global_context();
bool allow_map_transition = safe_to_add_transition &&
(global_context->object_function()->map() != map());
if (allow_map_transition) {
MaybeObject* maybe_transition =
current_map->AddElementsTransition(to_kind, new_map);
if (maybe_transition->IsFailure()) return maybe_transition;
}
return new_map;
}
void JSObject::LocalLookupRealNamedProperty(String* name,
LookupResult* result) {
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return result->NotFound();
ASSERT(proto->IsJSGlobalObject());
// A GlobalProxy's prototype should always be a proper JSObject.
return JSObject::cast(proto)->LocalLookupRealNamedProperty(name, result);
}
if (HasFastProperties()) {
LookupInDescriptor(name, result);
if (result->IsFound()) {
// A property, a map transition or a null descriptor was found.
// We return all of these result types because
// LocalLookupRealNamedProperty is used when setting properties
// where map transitions and null descriptors are handled.
ASSERT(result->holder() == this && result->type() != NORMAL);
// Disallow caching for uninitialized constants. These can only
// occur as fields.
if (result->IsReadOnly() && result->type() == FIELD &&
FastPropertyAt(result->GetFieldIndex())->IsTheHole()) {
result->DisallowCaching();
}
return;
}
} else {
int entry = property_dictionary()->FindEntry(name);
if (entry != StringDictionary::kNotFound) {
Object* value = property_dictionary()->ValueAt(entry);
if (IsGlobalObject()) {
PropertyDetails d = property_dictionary()->DetailsAt(entry);
if (d.IsDeleted()) {
result->NotFound();
return;
}
value = JSGlobalPropertyCell::cast(value)->value();
}
// Make sure to disallow caching for uninitialized constants
// found in the dictionary-mode objects.
if (value->IsTheHole()) result->DisallowCaching();
result->DictionaryResult(this, entry);
return;
}
}
result->NotFound();
}
void JSObject::LookupRealNamedProperty(String* name, LookupResult* result) {
LocalLookupRealNamedProperty(name, result);
if (result->IsProperty()) return;
LookupRealNamedPropertyInPrototypes(name, result);
}
void JSObject::LookupRealNamedPropertyInPrototypes(String* name,
LookupResult* result) {
Heap* heap = GetHeap();
for (Object* pt = GetPrototype();
pt != heap->null_value();
pt = JSObject::cast(pt)->GetPrototype()) {
JSObject::cast(pt)->LocalLookupRealNamedProperty(name, result);
if (result->IsProperty() && (result->type() != INTERCEPTOR)) return;
}
result->NotFound();
}
// We only need to deal with CALLBACKS and INTERCEPTORS
MaybeObject* JSObject::SetPropertyWithFailedAccessCheck(
LookupResult* result,
String* name,
Object* value,
bool check_prototype,
StrictModeFlag strict_mode) {
if (check_prototype && !result->IsProperty()) {
LookupCallbackSetterInPrototypes(name, result);
}
if (result->IsProperty()) {
if (!result->IsReadOnly()) {
switch (result->type()) {
case CALLBACKS: {
Object* obj = result->GetCallbackObject();
if (obj->IsAccessorInfo()) {
AccessorInfo* info = AccessorInfo::cast(obj);
if (info->all_can_write()) {
return SetPropertyWithCallback(result->GetCallbackObject(),
name,
value,
result->holder(),
strict_mode);
}
}
break;
}
case INTERCEPTOR: {
// Try lookup real named properties. Note that only property can be
// set is callbacks marked as ALL_CAN_WRITE on the prototype chain.
LookupResult r(GetIsolate());
LookupRealNamedProperty(name, &r);
if (r.IsProperty()) {
return SetPropertyWithFailedAccessCheck(&r,
name,
value,
check_prototype,
strict_mode);
}
break;
}
default: {
break;
}
}
}
}
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<Object> value_handle(value);
isolate->ReportFailedAccessCheck(this, v8::ACCESS_SET);
return *value_handle;
}
MaybeObject* JSReceiver::SetProperty(LookupResult* result,
String* key,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
if (result->IsFound() && result->type() == HANDLER) {
return result->proxy()->SetPropertyWithHandler(
key, value, attributes, strict_mode);
} else {
return JSObject::cast(this)->SetPropertyForResult(
result, key, value, attributes, strict_mode);
}
}
bool JSProxy::HasPropertyWithHandler(String* name_raw) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<Object> receiver(this);
Handle<Object> name(name_raw);
Handle<Object> args[] = { name };
Handle<Object> result = CallTrap(
"has", isolate->derived_has_trap(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return Failure::Exception();
return result->ToBoolean()->IsTrue();
}
MUST_USE_RESULT MaybeObject* JSProxy::SetPropertyWithHandler(
String* name_raw,
Object* value_raw,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<Object> receiver(this);
Handle<Object> name(name_raw);
Handle<Object> value(value_raw);
Handle<Object> args[] = { receiver, name, value };
CallTrap("set", isolate->derived_set_trap(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return Failure::Exception();
return *value;
}
MUST_USE_RESULT MaybeObject* JSProxy::SetPropertyWithHandlerIfDefiningSetter(
String* name_raw,
Object* value_raw,
PropertyAttributes attributes,
StrictModeFlag strict_mode,
bool* found) {
*found = true; // except where defined otherwise...
Isolate* isolate = GetHeap()->isolate();
Handle<JSProxy> proxy(this);
Handle<Object> handler(this->handler()); // Trap might morph proxy.
Handle<String> name(name_raw);
Handle<Object> value(value_raw);
Handle<Object> args[] = { name };
Handle<Object> result = proxy->CallTrap(
"getPropertyDescriptor", Handle<Object>(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return Failure::Exception();
if (!result->IsUndefined()) {
// The proxy handler cares about this property.
// Check whether it is virtualized as an accessor.
// Emulate [[GetProperty]] semantics for proxies.
bool has_pending_exception;
Handle<Object> argv[] = { result };
Handle<Object> desc =
Execution::Call(isolate->to_complete_property_descriptor(), result,
ARRAY_SIZE(argv), argv, &has_pending_exception);
if (has_pending_exception) return Failure::Exception();
Handle<String> conf_name =
isolate->factory()->LookupAsciiSymbol("configurable_");
Handle<Object> configurable(v8::internal::GetProperty(desc, conf_name));
ASSERT(!isolate->has_pending_exception());
if (configurable->IsFalse()) {
Handle<String> trap =
isolate->factory()->LookupAsciiSymbol("getPropertyDescriptor");
Handle<Object> args[] = { handler, trap, name };
Handle<Object> error = isolate->factory()->NewTypeError(
"proxy_prop_not_configurable", HandleVector(args, ARRAY_SIZE(args)));
return isolate->Throw(*error);
}
ASSERT(configurable->IsTrue());
// Check for AccessorDescriptor.
Handle<String> set_name = isolate->factory()->LookupAsciiSymbol("set_");
Handle<Object> setter(v8::internal::GetProperty(desc, set_name));
ASSERT(!isolate->has_pending_exception());
if (!setter->IsUndefined()) {
// We have a setter -- invoke it.
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return proxy->SetPropertyWithDefinedSetter(
JSReceiver::cast(*setter), *value);
} else {
Handle<String> get_name = isolate->factory()->LookupAsciiSymbol("get_");
Handle<Object> getter(v8::internal::GetProperty(desc, get_name));
ASSERT(!isolate->has_pending_exception());
if (!getter->IsUndefined()) {
// We have a getter but no setter -- the property may not be
// written. In strict mode, throw an error.
if (strict_mode == kNonStrictMode) return *value;
Handle<Object> args[] = { name, proxy };
Handle<Object> error = isolate->factory()->NewTypeError(
"no_setter_in_callback", HandleVector(args, ARRAY_SIZE(args)));
return isolate->Throw(*error);
}
}
// Fall-through.
}
// The proxy does not define the property as an accessor.
*found = false;
return *value;
}
MUST_USE_RESULT MaybeObject* JSProxy::DeletePropertyWithHandler(
String* name_raw, DeleteMode mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<Object> receiver(this);
Handle<Object> name(name_raw);
Handle<Object> args[] = { name };
Handle<Object> result = CallTrap(
"delete", Handle<Object>(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return Failure::Exception();
Object* bool_result = result->ToBoolean();
if (mode == STRICT_DELETION && bool_result == GetHeap()->false_value()) {
Handle<String> trap_name = isolate->factory()->LookupAsciiSymbol("delete");
Handle<Object> args[] = { Handle<Object>(handler()), trap_name };
Handle<Object> error = isolate->factory()->NewTypeError(
"handler_failed", HandleVector(args, ARRAY_SIZE(args)));
isolate->Throw(*error);
return Failure::Exception();
}
return bool_result;
}
MUST_USE_RESULT MaybeObject* JSProxy::DeleteElementWithHandler(
uint32_t index,
DeleteMode mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<String> name = isolate->factory()->Uint32ToString(index);
return JSProxy::DeletePropertyWithHandler(*name, mode);
}
MUST_USE_RESULT PropertyAttributes JSProxy::GetPropertyAttributeWithHandler(
JSReceiver* receiver_raw,
String* name_raw) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<JSProxy> proxy(this);
Handle<Object> handler(this->handler()); // Trap might morph proxy.
Handle<JSReceiver> receiver(receiver_raw);
Handle<Object> name(name_raw);
Handle<Object> args[] = { name };
Handle<Object> result = CallTrap(
"getPropertyDescriptor", Handle<Object>(), ARRAY_SIZE(args), args);
if (isolate->has_pending_exception()) return NONE;
if (result->IsUndefined()) return ABSENT;
bool has_pending_exception;
Handle<Object> argv[] = { result };
Handle<Object> desc =
Execution::Call(isolate->to_complete_property_descriptor(), result,
ARRAY_SIZE(argv), argv, &has_pending_exception);
if (has_pending_exception) return NONE;
// Convert result to PropertyAttributes.
Handle<String> enum_n = isolate->factory()->LookupAsciiSymbol("enumerable");
Handle<Object> enumerable(v8::internal::GetProperty(desc, enum_n));
if (isolate->has_pending_exception()) return NONE;
Handle<String> conf_n = isolate->factory()->LookupAsciiSymbol("configurable");
Handle<Object> configurable(v8::internal::GetProperty(desc, conf_n));
if (isolate->has_pending_exception()) return NONE;
Handle<String> writ_n = isolate->factory()->LookupAsciiSymbol("writable");
Handle<Object> writable(v8::internal::GetProperty(desc, writ_n));
if (isolate->has_pending_exception()) return NONE;
if (configurable->IsFalse()) {
Handle<String> trap =
isolate->factory()->LookupAsciiSymbol("getPropertyDescriptor");
Handle<Object> args[] = { handler, trap, name };
Handle<Object> error = isolate->factory()->NewTypeError(
"proxy_prop_not_configurable", HandleVector(args, ARRAY_SIZE(args)));
isolate->Throw(*error);
return NONE;
}
int attributes = NONE;
if (enumerable->ToBoolean()->IsFalse()) attributes |= DONT_ENUM;
if (configurable->ToBoolean()->IsFalse()) attributes |= DONT_DELETE;
if (writable->ToBoolean()->IsFalse()) attributes |= READ_ONLY;
return static_cast<PropertyAttributes>(attributes);
}
MUST_USE_RESULT PropertyAttributes JSProxy::GetElementAttributeWithHandler(
JSReceiver* receiver,
uint32_t index) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<String> name = isolate->factory()->Uint32ToString(index);
return GetPropertyAttributeWithHandler(receiver, *name);
}
void JSProxy::Fix() {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<JSProxy> self(this);
// Save identity hash.
MaybeObject* maybe_hash = GetIdentityHash(OMIT_CREATION);
if (IsJSFunctionProxy()) {
isolate->factory()->BecomeJSFunction(self);
// Code will be set on the JavaScript side.
} else {
isolate->factory()->BecomeJSObject(self);
}
ASSERT(self->IsJSObject());
// Inherit identity, if it was present.
Object* hash;
if (maybe_hash->To<Object>(&hash) && hash->IsSmi()) {
Handle<JSObject> new_self(JSObject::cast(*self));
isolate->factory()->SetIdentityHash(new_self, hash);
}
}
MUST_USE_RESULT Handle<Object> JSProxy::CallTrap(const char* name,
Handle<Object> derived,
int argc,
Handle<Object> argv[]) {
Isolate* isolate = GetIsolate();
Handle<Object> handler(this->handler());
Handle<String> trap_name = isolate->factory()->LookupAsciiSymbol(name);
Handle<Object> trap(v8::internal::GetProperty(handler, trap_name));
if (isolate->has_pending_exception()) return trap;
if (trap->IsUndefined()) {
if (derived.is_null()) {
Handle<Object> args[] = { handler, trap_name };
Handle<Object> error = isolate->factory()->NewTypeError(
"handler_trap_missing", HandleVector(args, ARRAY_SIZE(args)));
isolate->Throw(*error);
return Handle<Object>();
}
trap = Handle<Object>(derived);
}
bool threw;
return Execution::Call(trap, handler, argc, argv, &threw);
}
MaybeObject* JSObject::SetPropertyForResult(LookupResult* result,
String* name,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode) {
Heap* heap = GetHeap();
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc;
// Optimization for 2-byte strings often used as keys in a decompression
// dictionary. We make these short keys into symbols to avoid constantly
// reallocating them.
if (!name->IsSymbol() && name->length() <= 2) {
Object* symbol_version;
{ MaybeObject* maybe_symbol_version = heap->LookupSymbol(name);
if (maybe_symbol_version->ToObject(&symbol_version)) {
name = String::cast(symbol_version);
}
}
}
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
if (!heap->isolate()->MayNamedAccess(this, name, v8::ACCESS_SET)) {
return SetPropertyWithFailedAccessCheck(
result, name, value, true, strict_mode);
}
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return value;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->SetPropertyForResult(
result, name, value, attributes, strict_mode);
}
if (!result->IsProperty() && !IsJSContextExtensionObject()) {
bool found = false;
MaybeObject* result_object;
result_object = SetPropertyWithCallbackSetterInPrototypes(name,
value,
attributes,
&found,
strict_mode);
if (found) return result_object;
}
// At this point, no GC should have happened, as this would invalidate
// 'result', which we cannot handlify!
if (!result->IsFound()) {
// Neither properties nor transitions found.
return AddProperty(name, value, attributes, strict_mode);
}
if (result->IsReadOnly() && result->IsProperty()) {
if (strict_mode == kStrictMode) {
Handle<JSObject> self(this);
Handle<String> hname(name);
Handle<Object> args[] = { hname, self };
return heap->isolate()->Throw(*heap->isolate()->factory()->NewTypeError(
"strict_read_only_property", HandleVector(args, ARRAY_SIZE(args))));
} else {
return value;
}
}
// This is a real property that is not read-only, or it is a
// transition or null descriptor and there are no setters in the prototypes.
switch (result->type()) {
case NORMAL:
return SetNormalizedProperty(result, value);
case FIELD:
return FastPropertyAtPut(result->GetFieldIndex(), value);
case MAP_TRANSITION:
if (attributes == result->GetAttributes()) {
// Only use map transition if the attributes match.
return AddFastPropertyUsingMap(result->GetTransitionMap(),
name,
value);
}
return ConvertDescriptorToField(name, value, attributes);
case CONSTANT_FUNCTION:
// Only replace the function if necessary.
if (value == result->GetConstantFunction()) return value;
// Preserve the attributes of this existing property.
attributes = result->GetAttributes();
return ConvertDescriptorToField(name, value, attributes);
case CALLBACKS:
return SetPropertyWithCallback(result->GetCallbackObject(),
name,
value,
result->holder(),
strict_mode);
case INTERCEPTOR:
return SetPropertyWithInterceptor(name, value, attributes, strict_mode);
case CONSTANT_TRANSITION: {
// If the same constant function is being added we can simply
// transition to the target map.
Map* target_map = result->GetTransitionMap();
DescriptorArray* target_descriptors = target_map->instance_descriptors();
int number = target_descriptors->SearchWithCache(name);
ASSERT(number != DescriptorArray::kNotFound);
ASSERT(target_descriptors->GetType(number) == CONSTANT_FUNCTION);
JSFunction* function =
JSFunction::cast(target_descriptors->GetValue(number));
if (value == function) {
set_map(target_map);
return value;
}
// Otherwise, replace with a MAP_TRANSITION to a new map with a
// FIELD, even if the value is a constant function.
return ConvertDescriptorToFieldAndMapTransition(name, value, attributes);
}
case NULL_DESCRIPTOR:
case ELEMENTS_TRANSITION:
return ConvertDescriptorToFieldAndMapTransition(name, value, attributes);
case HANDLER:
UNREACHABLE();
return value;
}
UNREACHABLE(); // keep the compiler happy
return value;
}
// Set a real local property, even if it is READ_ONLY. If the property is not
// present, add it with attributes NONE. This code is an exact clone of
// SetProperty, with the check for IsReadOnly and the check for a
// callback setter removed. The two lines looking up the LookupResult
// result are also added. If one of the functions is changed, the other
// should be.
// Note that this method cannot be used to set the prototype of a function
// because ConvertDescriptorToField() which is called in "case CALLBACKS:"
// doesn't handle function prototypes correctly.
Handle<Object> JSObject::SetLocalPropertyIgnoreAttributes(
Handle<JSObject> object,
Handle<String> key,
Handle<Object> value,
PropertyAttributes attributes) {
CALL_HEAP_FUNCTION(
object->GetIsolate(),
object->SetLocalPropertyIgnoreAttributes(*key, *value, attributes),
Object);
}
MaybeObject* JSObject::SetLocalPropertyIgnoreAttributes(
String* name,
Object* value,
PropertyAttributes attributes) {
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc;
Isolate* isolate = GetIsolate();
LookupResult result(isolate);
LocalLookup(name, &result);
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
if (!isolate->MayNamedAccess(this, name, v8::ACCESS_SET)) {
return SetPropertyWithFailedAccessCheck(&result,
name,
value,
false,
kNonStrictMode);
}
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return value;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->SetLocalPropertyIgnoreAttributes(
name,
value,
attributes);
}
// Check for accessor in prototype chain removed here in clone.
if (!result.IsFound()) {
// Neither properties nor transitions found.
return AddProperty(name, value, attributes, kNonStrictMode);
}
PropertyDetails details = PropertyDetails(attributes, NORMAL);
// Check of IsReadOnly removed from here in clone.
switch (result.type()) {
case NORMAL:
return SetNormalizedProperty(name, value, details);
case FIELD:
return FastPropertyAtPut(result.GetFieldIndex(), value);
case MAP_TRANSITION:
if (attributes == result.GetAttributes()) {
// Only use map transition if the attributes match.
return AddFastPropertyUsingMap(result.GetTransitionMap(),
name,
value);
}
return ConvertDescriptorToField(name, value, attributes);
case CONSTANT_FUNCTION:
// Only replace the function if necessary.
if (value == result.GetConstantFunction()) return value;
// Preserve the attributes of this existing property.
attributes = result.GetAttributes();
return ConvertDescriptorToField(name, value, attributes);
case CALLBACKS:
case INTERCEPTOR:
// Override callback in clone
return ConvertDescriptorToField(name, value, attributes);
case CONSTANT_TRANSITION:
// Replace with a MAP_TRANSITION to a new map with a FIELD, even
// if the value is a function.
return ConvertDescriptorToFieldAndMapTransition(name, value, attributes);
case NULL_DESCRIPTOR:
case ELEMENTS_TRANSITION:
return ConvertDescriptorToFieldAndMapTransition(name, value, attributes);
case HANDLER:
UNREACHABLE();
return value;
}
UNREACHABLE(); // keep the compiler happy
return value;
}
PropertyAttributes JSObject::GetPropertyAttributePostInterceptor(
JSObject* receiver,
String* name,
bool continue_search) {
// Check local property, ignore interceptor.
LookupResult result(GetIsolate());
LocalLookupRealNamedProperty(name, &result);
if (result.IsProperty()) return result.GetAttributes();
if (continue_search) {
// Continue searching via the prototype chain.
Object* pt = GetPrototype();
if (!pt->IsNull()) {
return JSObject::cast(pt)->
GetPropertyAttributeWithReceiver(receiver, name);
}
}
return ABSENT;
}
PropertyAttributes JSObject::GetPropertyAttributeWithInterceptor(
JSObject* receiver,
String* name,
bool continue_search) {
Isolate* isolate = GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetNamedInterceptor());
Handle<JSObject> receiver_handle(receiver);
Handle<JSObject> holder_handle(this);
Handle<String> name_handle(name);
CustomArguments args(isolate, interceptor->data(), receiver, this);
v8::AccessorInfo info(args.end());
if (!interceptor->query()->IsUndefined()) {
v8::NamedPropertyQuery query =
v8::ToCData<v8::NamedPropertyQuery>(interceptor->query());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-has", *holder_handle, name));
v8::Handle<v8::Integer> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = query(v8::Utils::ToLocal(name_handle), info);
}
if (!result.IsEmpty()) {
ASSERT(result->IsInt32());
return static_cast<PropertyAttributes>(result->Int32Value());
}
} else if (!interceptor->getter()->IsUndefined()) {
v8::NamedPropertyGetter getter =
v8::ToCData<v8::NamedPropertyGetter>(interceptor->getter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-get-has", this, name));
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = getter(v8::Utils::ToLocal(name_handle), info);
}
if (!result.IsEmpty()) return DONT_ENUM;
}
return holder_handle->GetPropertyAttributePostInterceptor(*receiver_handle,
*name_handle,
continue_search);
}
PropertyAttributes JSReceiver::GetPropertyAttributeWithReceiver(
JSReceiver* receiver,
String* key) {
uint32_t index = 0;
if (IsJSObject() && key->AsArrayIndex(&index)) {
return JSObject::cast(this)->HasElementWithReceiver(receiver, index)
? NONE : ABSENT;
}
// Named property.
LookupResult result(GetIsolate());
Lookup(key, &result);
return GetPropertyAttribute(receiver, &result, key, true);
}
PropertyAttributes JSReceiver::GetPropertyAttribute(JSReceiver* receiver,
LookupResult* result,
String* name,
bool continue_search) {
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
JSObject* this_obj = JSObject::cast(this);
Heap* heap = GetHeap();
if (!heap->isolate()->MayNamedAccess(this_obj, name, v8::ACCESS_HAS)) {
return this_obj->GetPropertyAttributeWithFailedAccessCheck(
receiver, result, name, continue_search);
}
}
if (result->IsProperty()) {
switch (result->type()) {
case NORMAL: // fall through
case FIELD:
case CONSTANT_FUNCTION:
case CALLBACKS:
return result->GetAttributes();
case HANDLER: {
return JSProxy::cast(result->proxy())->GetPropertyAttributeWithHandler(
receiver, name);
}
case INTERCEPTOR:
return result->holder()->GetPropertyAttributeWithInterceptor(
JSObject::cast(receiver), name, continue_search);
default:
UNREACHABLE();
}
}
return ABSENT;
}
PropertyAttributes JSReceiver::GetLocalPropertyAttribute(String* name) {
// Check whether the name is an array index.
uint32_t index = 0;
if (IsJSObject() && name->AsArrayIndex(&index)) {
if (JSObject::cast(this)->HasLocalElement(index)) return NONE;
return ABSENT;
}
// Named property.
LookupResult result(GetIsolate());
LocalLookup(name, &result);
return GetPropertyAttribute(this, &result, name, false);
}
MaybeObject* NormalizedMapCache::Get(JSObject* obj,
PropertyNormalizationMode mode) {
Isolate* isolate = obj->GetIsolate();
Map* fast = obj->map();
int index = fast->Hash() % kEntries;
Object* result = get(index);
if (result->IsMap() &&
Map::cast(result)->EquivalentToForNormalization(fast, mode)) {
#ifdef DEBUG
if (FLAG_verify_heap) {
Map::cast(result)->SharedMapVerify();
}
if (FLAG_enable_slow_asserts) {
// The cached map should match newly created normalized map bit-by-bit.
Object* fresh;
{ MaybeObject* maybe_fresh =
fast->CopyNormalized(mode, SHARED_NORMALIZED_MAP);
if (maybe_fresh->ToObject(&fresh)) {
ASSERT(memcmp(Map::cast(fresh)->address(),
Map::cast(result)->address(),
Map::kSize) == 0);
}
}
}
#endif
return result;
}
{ MaybeObject* maybe_result =
fast->CopyNormalized(mode, SHARED_NORMALIZED_MAP);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
set(index, result);
isolate->counters()->normalized_maps()->Increment();
return result;
}
void NormalizedMapCache::Clear() {
int entries = length();
for (int i = 0; i != entries; i++) {
set_undefined(i);
}
}
void JSObject::UpdateMapCodeCache(Handle<JSObject> object,
Handle<String> name,
Handle<Code> code) {
Isolate* isolate = object->GetIsolate();
CALL_HEAP_FUNCTION_VOID(isolate,
object->UpdateMapCodeCache(*name, *code));
}
MaybeObject* JSObject::UpdateMapCodeCache(String* name, Code* code) {
if (map()->is_shared()) {
// Fast case maps are never marked as shared.
ASSERT(!HasFastProperties());
// Replace the map with an identical copy that can be safely modified.
Object* obj;
{ MaybeObject* maybe_obj = map()->CopyNormalized(KEEP_INOBJECT_PROPERTIES,
UNIQUE_NORMALIZED_MAP);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
GetIsolate()->counters()->normalized_maps()->Increment();
set_map(Map::cast(obj));
}
return map()->UpdateCodeCache(name, code);
}
void JSObject::NormalizeProperties(Handle<JSObject> object,
PropertyNormalizationMode mode,
int expected_additional_properties) {
CALL_HEAP_FUNCTION_VOID(object->GetIsolate(),
object->NormalizeProperties(
mode, expected_additional_properties));
}
MaybeObject* JSObject::NormalizeProperties(PropertyNormalizationMode mode,
int expected_additional_properties) {
if (!HasFastProperties()) return this;
// The global object is always normalized.
ASSERT(!IsGlobalObject());
// JSGlobalProxy must never be normalized
ASSERT(!IsJSGlobalProxy());
Map* map_of_this = map();
// Allocate new content.
int property_count = map_of_this->NumberOfDescribedProperties();
if (expected_additional_properties > 0) {
property_count += expected_additional_properties;
} else {
property_count += 2; // Make space for two more properties.
}
StringDictionary* dictionary;
{ MaybeObject* maybe_dictionary = StringDictionary::Allocate(property_count);
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
}
DescriptorArray* descs = map_of_this->instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
PropertyDetails details(descs->GetDetails(i));
switch (details.type()) {
case CONSTANT_FUNCTION: {
PropertyDetails d =
PropertyDetails(details.attributes(), NORMAL, details.index());
Object* value = descs->GetConstantFunction(i);
MaybeObject* maybe_dictionary =
dictionary->Add(descs->GetKey(i), value, d);
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
break;
}
case FIELD: {
PropertyDetails d =
PropertyDetails(details.attributes(), NORMAL, details.index());
Object* value = FastPropertyAt(descs->GetFieldIndex(i));
MaybeObject* maybe_dictionary =
dictionary->Add(descs->GetKey(i), value, d);
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
break;
}
case CALLBACKS: {
if (!descs->IsProperty(i)) break;
Object* value = descs->GetCallbacksObject(i);
if (value->IsAccessorPair()) {
MaybeObject* maybe_copy =
AccessorPair::cast(value)->CopyWithoutTransitions();
if (!maybe_copy->To(&value)) return maybe_copy;
}
MaybeObject* maybe_dictionary =
dictionary->Add(descs->GetKey(i), value, details);
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
break;
}
case MAP_TRANSITION:
case CONSTANT_TRANSITION:
case NULL_DESCRIPTOR:
case INTERCEPTOR:
case ELEMENTS_TRANSITION:
break;
case HANDLER:
case NORMAL:
UNREACHABLE();
break;
}
}
Heap* current_heap = GetHeap();
// Copy the next enumeration index from instance descriptor.
int index = map_of_this->instance_descriptors()->NextEnumerationIndex();
dictionary->SetNextEnumerationIndex(index);
Map* new_map;
{ MaybeObject* maybe_map =
current_heap->isolate()->context()->global_context()->
normalized_map_cache()->Get(this, mode);
if (!maybe_map->To(&new_map)) return maybe_map;
}
// We have now successfully allocated all the necessary objects.
// Changes can now be made with the guarantee that all of them take effect.
// Resize the object in the heap if necessary.
int new_instance_size = new_map->instance_size();
int instance_size_delta = map_of_this->instance_size() - new_instance_size;
ASSERT(instance_size_delta >= 0);
current_heap->CreateFillerObjectAt(this->address() + new_instance_size,
instance_size_delta);
if (Marking::IsBlack(Marking::MarkBitFrom(this))) {
MemoryChunk::IncrementLiveBytesFromMutator(this->address(),
-instance_size_delta);
}
set_map(new_map);
new_map->clear_instance_descriptors();
set_properties(dictionary);
current_heap->isolate()->counters()->props_to_dictionary()->Increment();
#ifdef DEBUG
if (FLAG_trace_normalization) {
PrintF("Object properties have been normalized:\n");
Print();
}
#endif
return this;
}
void JSObject::TransformToFastProperties(Handle<JSObject> object,
int unused_property_fields) {
CALL_HEAP_FUNCTION_VOID(
object->GetIsolate(),
object->TransformToFastProperties(unused_property_fields));
}
MaybeObject* JSObject::TransformToFastProperties(int unused_property_fields) {
if (HasFastProperties()) return this;
ASSERT(!IsGlobalObject());
return property_dictionary()->
TransformPropertiesToFastFor(this, unused_property_fields);
}
Handle<SeededNumberDictionary> JSObject::NormalizeElements(
Handle<JSObject> object) {
CALL_HEAP_FUNCTION(object->GetIsolate(),
object->NormalizeElements(),
SeededNumberDictionary);
}
MaybeObject* JSObject::NormalizeElements() {
ASSERT(!HasExternalArrayElements());
// Find the backing store.
FixedArrayBase* array = FixedArrayBase::cast(elements());
Map* old_map = array->map();
bool is_arguments =
(old_map == old_map->GetHeap()->non_strict_arguments_elements_map());
if (is_arguments) {
array = FixedArrayBase::cast(FixedArray::cast(array)->get(1));
}
if (array->IsDictionary()) return array;
ASSERT(HasFastElements() ||
HasFastSmiOnlyElements() ||
HasFastDoubleElements() ||
HasFastArgumentsElements());
// Compute the effective length and allocate a new backing store.
int length = IsJSArray()
? Smi::cast(JSArray::cast(this)->length())->value()
: array->length();
int old_capacity = 0;
int used_elements = 0;
GetElementsCapacityAndUsage(&old_capacity, &used_elements);
SeededNumberDictionary* dictionary = NULL;
{ Object* object;
MaybeObject* maybe = SeededNumberDictionary::Allocate(used_elements);
if (!maybe->ToObject(&object)) return maybe;
dictionary = SeededNumberDictionary::cast(object);
}
// Copy the elements to the new backing store.
bool has_double_elements = array->IsFixedDoubleArray();
for (int i = 0; i < length; i++) {
Object* value = NULL;
if (has_double_elements) {
FixedDoubleArray* double_array = FixedDoubleArray::cast(array);
if (double_array->is_the_hole(i)) {
value = GetIsolate()->heap()->the_hole_value();
} else {
// Objects must be allocated in the old object space, since the
// overall number of HeapNumbers needed for the conversion might
// exceed the capacity of new space, and we would fail repeatedly
// trying to convert the FixedDoubleArray.
MaybeObject* maybe_value_object =
GetHeap()->AllocateHeapNumber(double_array->get_scalar(i), TENURED);
if (!maybe_value_object->ToObject(&value)) return maybe_value_object;
}
} else {
ASSERT(old_map->has_fast_elements() ||
old_map->has_fast_smi_only_elements());
value = FixedArray::cast(array)->get(i);
}
PropertyDetails details = PropertyDetails(NONE, NORMAL);
if (!value->IsTheHole()) {
Object* result;
MaybeObject* maybe_result =
dictionary->AddNumberEntry(i, value, details);
if (!maybe_result->ToObject(&result)) return maybe_result;
dictionary = SeededNumberDictionary::cast(result);
}
}
// Switch to using the dictionary as the backing storage for elements.
if (is_arguments) {
FixedArray::cast(elements())->set(1, dictionary);
} else {
// Set the new map first to satify the elements type assert in
// set_elements().
Object* new_map;
MaybeObject* maybe = GetElementsTransitionMap(GetIsolate(),
DICTIONARY_ELEMENTS);
if (!maybe->ToObject(&new_map)) return maybe;
set_map(Map::cast(new_map));
set_elements(dictionary);
}
old_map->GetHeap()->isolate()->counters()->elements_to_dictionary()->
Increment();
#ifdef DEBUG
if (FLAG_trace_normalization) {
PrintF("Object elements have been normalized:\n");
Print();
}
#endif
ASSERT(HasDictionaryElements() || HasDictionaryArgumentsElements());
return dictionary;
}
Smi* JSReceiver::GenerateIdentityHash() {
Isolate* isolate = GetIsolate();
int hash_value;
int attempts = 0;
do {
// Generate a random 32-bit hash value but limit range to fit
// within a smi.
hash_value = V8::RandomPrivate(isolate) & Smi::kMaxValue;
attempts++;
} while (hash_value == 0 && attempts < 30);
hash_value = hash_value != 0 ? hash_value : 1; // never return 0
return Smi::FromInt(hash_value);
}
MaybeObject* JSObject::SetIdentityHash(Object* hash, CreationFlag flag) {
MaybeObject* maybe = SetHiddenProperty(GetHeap()->identity_hash_symbol(),
hash);
if (maybe->IsFailure()) return maybe;
return this;
}
int JSObject::GetIdentityHash(Handle<JSObject> obj) {
CALL_AND_RETRY(obj->GetIsolate(),
obj->GetIdentityHash(ALLOW_CREATION),
return Smi::cast(__object__)->value(),
return 0);
}
MaybeObject* JSObject::GetIdentityHash(CreationFlag flag) {
Object* stored_value = GetHiddenProperty(GetHeap()->identity_hash_symbol());
if (stored_value->IsSmi()) return stored_value;
// Do not generate permanent identity hash code if not requested.
if (flag == OMIT_CREATION) return GetHeap()->undefined_value();
Smi* hash = GenerateIdentityHash();
MaybeObject* result = SetHiddenProperty(GetHeap()->identity_hash_symbol(),
hash);
if (result->IsFailure()) return result;
if (result->ToObjectUnchecked()->IsUndefined()) {
// Trying to get hash of detached proxy.
return Smi::FromInt(0);
}
return hash;
}
MaybeObject* JSProxy::GetIdentityHash(CreationFlag flag) {
Object* hash = this->hash();
if (!hash->IsSmi() && flag == ALLOW_CREATION) {
hash = GenerateIdentityHash();
set_hash(hash);
}
return hash;
}
Object* JSObject::GetHiddenProperty(String* key) {
if (IsJSGlobalProxy()) {
// For a proxy, use the prototype as target object.
Object* proxy_parent = GetPrototype();
// If the proxy is detached, return undefined.
if (proxy_parent->IsNull()) return GetHeap()->undefined_value();
ASSERT(proxy_parent->IsJSGlobalObject());
return JSObject::cast(proxy_parent)->GetHiddenProperty(key);
}
ASSERT(!IsJSGlobalProxy());
MaybeObject* hidden_lookup = GetHiddenPropertiesDictionary(false);
ASSERT(!hidden_lookup->IsFailure()); // No failure when passing false as arg.
if (hidden_lookup->ToObjectUnchecked()->IsUndefined()) {
return GetHeap()->undefined_value();
}
StringDictionary* dictionary =
StringDictionary::cast(hidden_lookup->ToObjectUnchecked());
int entry = dictionary->FindEntry(key);
if (entry == StringDictionary::kNotFound) return GetHeap()->undefined_value();
return dictionary->ValueAt(entry);
}
Handle<Object> JSObject::SetHiddenProperty(Handle<JSObject> obj,
Handle<String> key,
Handle<Object> value) {
CALL_HEAP_FUNCTION(obj->GetIsolate(),
obj->SetHiddenProperty(*key, *value),
Object);
}
MaybeObject* JSObject::SetHiddenProperty(String* key, Object* value) {
if (IsJSGlobalProxy()) {
// For a proxy, use the prototype as target object.
Object* proxy_parent = GetPrototype();
// If the proxy is detached, return undefined.
if (proxy_parent->IsNull()) return GetHeap()->undefined_value();
ASSERT(proxy_parent->IsJSGlobalObject());
return JSObject::cast(proxy_parent)->SetHiddenProperty(key, value);
}
ASSERT(!IsJSGlobalProxy());
MaybeObject* hidden_lookup = GetHiddenPropertiesDictionary(true);
StringDictionary* dictionary;
if (!hidden_lookup->To<StringDictionary>(&dictionary)) return hidden_lookup;
// If it was found, check if the key is already in the dictionary.
int entry = dictionary->FindEntry(key);
if (entry != StringDictionary::kNotFound) {
// If key was found, just update the value.
dictionary->ValueAtPut(entry, value);
return this;
}
// Key was not already in the dictionary, so add the entry.
MaybeObject* insert_result = dictionary->Add(key,
value,
PropertyDetails(NONE, NORMAL));
StringDictionary* new_dict;
if (!insert_result->To<StringDictionary>(&new_dict)) return insert_result;
if (new_dict != dictionary) {
// If adding the key expanded the dictionary (i.e., Add returned a new
// dictionary), store it back to the object.
MaybeObject* store_result = SetHiddenPropertiesDictionary(new_dict);
if (store_result->IsFailure()) return store_result;
}
// Return this to mark success.
return this;
}
void JSObject::DeleteHiddenProperty(String* key) {
if (IsJSGlobalProxy()) {
// For a proxy, use the prototype as target object.
Object* proxy_parent = GetPrototype();
// If the proxy is detached, return immediately.
if (proxy_parent->IsNull()) return;
ASSERT(proxy_parent->IsJSGlobalObject());
JSObject::cast(proxy_parent)->DeleteHiddenProperty(key);
return;
}
MaybeObject* hidden_lookup = GetHiddenPropertiesDictionary(false);
ASSERT(!hidden_lookup->IsFailure()); // No failure when passing false as arg.
if (hidden_lookup->ToObjectUnchecked()->IsUndefined()) return;
StringDictionary* dictionary =
StringDictionary::cast(hidden_lookup->ToObjectUnchecked());
int entry = dictionary->FindEntry(key);
if (entry == StringDictionary::kNotFound) {
// Key wasn't in dictionary. Deletion is a success.
return;
}
// Key was in the dictionary. Remove it.
dictionary->DeleteProperty(entry, JSReceiver::FORCE_DELETION);
}
bool JSObject::HasHiddenProperties() {
return GetPropertyAttributePostInterceptor(this,
GetHeap()->hidden_symbol(),
false) != ABSENT;
}
MaybeObject* JSObject::GetHiddenPropertiesDictionary(bool create_if_absent) {
ASSERT(!IsJSGlobalProxy());
if (HasFastProperties()) {
// If the object has fast properties, check whether the first slot
// in the descriptor array matches the hidden symbol. Since the
// hidden symbols hash code is zero (and no other string has hash
// code zero) it will always occupy the first entry if present.
DescriptorArray* descriptors = this->map()->instance_descriptors();
if ((descriptors->number_of_descriptors() > 0) &&
(descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
if (descriptors->GetType(0) == FIELD) {
Object* hidden_store =
this->FastPropertyAt(descriptors->GetFieldIndex(0));
return StringDictionary::cast(hidden_store);
} else {
ASSERT(descriptors->GetType(0) == NULL_DESCRIPTOR ||
descriptors->GetType(0) == MAP_TRANSITION);
}
}
} else {
PropertyAttributes attributes;
// You can't install a getter on a property indexed by the hidden symbol,
// so we can be sure that GetLocalPropertyPostInterceptor returns a real
// object.
Object* lookup =
GetLocalPropertyPostInterceptor(this,
GetHeap()->hidden_symbol(),
&attributes)->ToObjectUnchecked();
if (!lookup->IsUndefined()) {
return StringDictionary::cast(lookup);
}
}
if (!create_if_absent) return GetHeap()->undefined_value();
const int kInitialSize = 5;
MaybeObject* dict_alloc = StringDictionary::Allocate(kInitialSize);
StringDictionary* dictionary;
if (!dict_alloc->To<StringDictionary>(&dictionary)) return dict_alloc;
MaybeObject* store_result =
SetPropertyPostInterceptor(GetHeap()->hidden_symbol(),
dictionary,
DONT_ENUM,
kNonStrictMode);
if (store_result->IsFailure()) return store_result;
return dictionary;
}
MaybeObject* JSObject::SetHiddenPropertiesDictionary(
StringDictionary* dictionary) {
ASSERT(!IsJSGlobalProxy());
ASSERT(HasHiddenProperties());
if (HasFastProperties()) {
// If the object has fast properties, check whether the first slot
// in the descriptor array matches the hidden symbol. Since the
// hidden symbols hash code is zero (and no other string has hash
// code zero) it will always occupy the first entry if present.
DescriptorArray* descriptors = this->map()->instance_descriptors();
if ((descriptors->number_of_descriptors() > 0) &&
(descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
if (descriptors->GetType(0) == FIELD) {
this->FastPropertyAtPut(descriptors->GetFieldIndex(0), dictionary);
return this;
} else {
ASSERT(descriptors->GetType(0) == NULL_DESCRIPTOR ||
descriptors->GetType(0) == MAP_TRANSITION);
}
}
}
MaybeObject* store_result =
SetPropertyPostInterceptor(GetHeap()->hidden_symbol(),
dictionary,
DONT_ENUM,
kNonStrictMode);
if (store_result->IsFailure()) return store_result;
return this;
}
MaybeObject* JSObject::DeletePropertyPostInterceptor(String* name,
DeleteMode mode) {
// Check local property, ignore interceptor.
LookupResult result(GetIsolate());
LocalLookupRealNamedProperty(name, &result);
if (!result.IsProperty()) return GetHeap()->true_value();
// Normalize object if needed.
Object* obj;
{ MaybeObject* maybe_obj = NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return DeleteNormalizedProperty(name, mode);
}
MaybeObject* JSObject::DeletePropertyWithInterceptor(String* name) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetNamedInterceptor());
Handle<String> name_handle(name);
Handle<JSObject> this_handle(this);
if (!interceptor->deleter()->IsUndefined()) {
v8::NamedPropertyDeleter deleter =
v8::ToCData<v8::NamedPropertyDeleter>(interceptor->deleter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-delete", *this_handle, name));
CustomArguments args(isolate, interceptor->data(), this, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Boolean> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = deleter(v8::Utils::ToLocal(name_handle), info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) {
ASSERT(result->IsBoolean());
return *v8::Utils::OpenHandle(*result);
}
}
MaybeObject* raw_result =
this_handle->DeletePropertyPostInterceptor(*name_handle, NORMAL_DELETION);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return raw_result;
}
MaybeObject* JSObject::DeleteElementWithInterceptor(uint32_t index) {
Isolate* isolate = GetIsolate();
Heap* heap = isolate->heap();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetIndexedInterceptor());
if (interceptor->deleter()->IsUndefined()) return heap->false_value();
v8::IndexedPropertyDeleter deleter =
v8::ToCData<v8::IndexedPropertyDeleter>(interceptor->deleter());
Handle<JSObject> this_handle(this);
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-delete", this, index));
CustomArguments args(isolate, interceptor->data(), this, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Boolean> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = deleter(index, info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) {
ASSERT(result->IsBoolean());
return *v8::Utils::OpenHandle(*result);
}
MaybeObject* raw_result = this_handle->GetElementsAccessor()->Delete(
*this_handle,
index,
NORMAL_DELETION);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return raw_result;
}
Handle<Object> JSObject::DeleteElement(Handle<JSObject> obj,
uint32_t index) {
CALL_HEAP_FUNCTION(obj->GetIsolate(),
obj->DeleteElement(index, JSObject::NORMAL_DELETION),
Object);
}
MaybeObject* JSObject::DeleteElement(uint32_t index, DeleteMode mode) {
Isolate* isolate = GetIsolate();
// Check access rights if needed.
if (IsAccessCheckNeeded() &&
!isolate->MayIndexedAccess(this, index, v8::ACCESS_DELETE)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_DELETE);
return isolate->heap()->false_value();
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return isolate->heap()->false_value();
ASSERT(proto->IsJSGlobalObject());
return JSGlobalObject::cast(proto)->DeleteElement(index, mode);
}
if (HasIndexedInterceptor()) {
// Skip interceptor if forcing deletion.
if (mode != FORCE_DELETION) {
return DeleteElementWithInterceptor(index);
}
mode = JSReceiver::FORCE_DELETION;
}
return GetElementsAccessor()->Delete(this, index, mode);
}
Handle<Object> JSObject::DeleteProperty(Handle<JSObject> obj,
Handle<String> prop) {
CALL_HEAP_FUNCTION(obj->GetIsolate(),
obj->DeleteProperty(*prop, JSObject::NORMAL_DELETION),
Object);
}
MaybeObject* JSObject::DeleteProperty(String* name, DeleteMode mode) {
Isolate* isolate = GetIsolate();
// ECMA-262, 3rd, 8.6.2.5
ASSERT(name->IsString());
// Check access rights if needed.
if (IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(this, name, v8::ACCESS_DELETE)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_DELETE);
return isolate->heap()->false_value();
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return isolate->heap()->false_value();
ASSERT(proto->IsJSGlobalObject());
return JSGlobalObject::cast(proto)->DeleteProperty(name, mode);
}
uint32_t index = 0;
if (name->AsArrayIndex(&index)) {
return DeleteElement(index, mode);
} else {
LookupResult result(isolate);
LocalLookup(name, &result);
if (!result.IsProperty()) return isolate->heap()->true_value();
// Ignore attributes if forcing a deletion.
if (result.IsDontDelete() && mode != FORCE_DELETION) {
if (mode == STRICT_DELETION) {
// Deleting a non-configurable property in strict mode.
HandleScope scope(isolate);
Handle<Object> args[2] = { Handle<Object>(name), Handle<Object>(this) };
return isolate->Throw(*isolate->factory()->NewTypeError(
"strict_delete_property", HandleVector(args, 2)));
}
return isolate->heap()->false_value();
}
// Check for interceptor.
if (result.type() == INTERCEPTOR) {
// Skip interceptor if forcing a deletion.
if (mode == FORCE_DELETION) {
return DeletePropertyPostInterceptor(name, mode);
}
return DeletePropertyWithInterceptor(name);
}
// Normalize object if needed.
Object* obj;
{ MaybeObject* maybe_obj =
NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
// Make sure the properties are normalized before removing the entry.
return DeleteNormalizedProperty(name, mode);
}
}
MaybeObject* JSReceiver::DeleteElement(uint32_t index, DeleteMode mode) {
if (IsJSProxy()) {
return JSProxy::cast(this)->DeleteElementWithHandler(index, mode);
}
return JSObject::cast(this)->DeleteElement(index, mode);
}
MaybeObject* JSReceiver::DeleteProperty(String* name, DeleteMode mode) {
if (IsJSProxy()) {
return JSProxy::cast(this)->DeletePropertyWithHandler(name, mode);
}
return JSObject::cast(this)->DeleteProperty(name, mode);
}
bool JSObject::ReferencesObjectFromElements(FixedArray* elements,
ElementsKind kind,
Object* object) {
ASSERT(kind == FAST_ELEMENTS ||
kind == DICTIONARY_ELEMENTS);
if (kind == FAST_ELEMENTS) {
int length = IsJSArray()
? Smi::cast(JSArray::cast(this)->length())->value()
: elements->length();
for (int i = 0; i < length; ++i) {
Object* element = elements->get(i);
if (!element->IsTheHole() && element == object) return true;
}
} else {
Object* key =
SeededNumberDictionary::cast(elements)->SlowReverseLookup(object);
if (!key->IsUndefined()) return true;
}
return false;
}
// Check whether this object references another object.
bool JSObject::ReferencesObject(Object* obj) {
Map* map_of_this = map();
Heap* heap = GetHeap();
AssertNoAllocation no_alloc;
// Is the object the constructor for this object?
if (map_of_this->constructor() == obj) {
return true;
}
// Is the object the prototype for this object?
if (map_of_this->prototype() == obj) {
return true;
}
// Check if the object is among the named properties.
Object* key = SlowReverseLookup(obj);
if (!key->IsUndefined()) {
return true;
}
// Check if the object is among the indexed properties.
ElementsKind kind = GetElementsKind();
switch (kind) {
case EXTERNAL_PIXEL_ELEMENTS:
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
// Raw pixels and external arrays do not reference other
// objects.
break;
case FAST_SMI_ONLY_ELEMENTS:
break;
case FAST_ELEMENTS:
case DICTIONARY_ELEMENTS: {
FixedArray* elements = FixedArray::cast(this->elements());
if (ReferencesObjectFromElements(elements, kind, obj)) return true;
break;
}
case NON_STRICT_ARGUMENTS_ELEMENTS: {
FixedArray* parameter_map = FixedArray::cast(elements());
// Check the mapped parameters.
int length = parameter_map->length();
for (int i = 2; i < length; ++i) {
Object* value = parameter_map->get(i);
if (!value->IsTheHole() && value == obj) return true;
}
// Check the arguments.
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
kind = arguments->IsDictionary() ? DICTIONARY_ELEMENTS : FAST_ELEMENTS;
if (ReferencesObjectFromElements(arguments, kind, obj)) return true;
break;
}
}
// For functions check the context.
if (IsJSFunction()) {
// Get the constructor function for arguments array.
JSObject* arguments_boilerplate =
heap->isolate()->context()->global_context()->
arguments_boilerplate();
JSFunction* arguments_function =
JSFunction::cast(arguments_boilerplate->map()->constructor());
// Get the context and don't check if it is the global context.
JSFunction* f = JSFunction::cast(this);
Context* context = f->context();
if (context->IsGlobalContext()) {
return false;
}
// Check the non-special context slots.
for (int i = Context::MIN_CONTEXT_SLOTS; i < context->length(); i++) {
// Only check JS objects.
if (context->get(i)->IsJSObject()) {
JSObject* ctxobj = JSObject::cast(context->get(i));
// If it is an arguments array check the content.
if (ctxobj->map()->constructor() == arguments_function) {
if (ctxobj->ReferencesObject(obj)) {
return true;
}
} else if (ctxobj == obj) {
return true;
}
}
}
// Check the context extension (if any) if it can have references.
if (context->has_extension() && !context->IsCatchContext()) {
return JSObject::cast(context->extension())->ReferencesObject(obj);
}
}
// No references to object.
return false;
}
Handle<Object> JSObject::PreventExtensions(Handle<JSObject> object) {
CALL_HEAP_FUNCTION(object->GetIsolate(), object->PreventExtensions(), Object);
}
MaybeObject* JSObject::PreventExtensions() {
Isolate* isolate = GetIsolate();
if (IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(this,
isolate->heap()->undefined_value(),
v8::ACCESS_KEYS)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_KEYS);
return isolate->heap()->false_value();
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return this;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->PreventExtensions();
}
// It's not possible to seal objects with external array elements
if (HasExternalArrayElements()) {
HandleScope scope(isolate);
Handle<Object> object(this);
Handle<Object> error =
isolate->factory()->NewTypeError(
"cant_prevent_ext_external_array_elements",
HandleVector(&object, 1));
return isolate->Throw(*error);
}
// If there are fast elements we normalize.
SeededNumberDictionary* dictionary = NULL;
{ MaybeObject* maybe = NormalizeElements();
if (!maybe->To<SeededNumberDictionary>(&dictionary)) return maybe;
}
ASSERT(HasDictionaryElements() || HasDictionaryArgumentsElements());
// Make sure that we never go back to fast case.
dictionary->set_requires_slow_elements();
// Do a map transition, other objects with this map may still
// be extensible.
Map* new_map;
{ MaybeObject* maybe = map()->CopyDropTransitions();
if (!maybe->To<Map>(&new_map)) return maybe;
}
new_map->set_is_extensible(false);
set_map(new_map);
ASSERT(!map()->is_extensible());
return new_map;
}
// Tests for the fast common case for property enumeration:
// - This object and all prototypes has an enum cache (which means that
// it is no proxy, has no interceptors and needs no access checks).
// - This object has no elements.
// - No prototype has enumerable properties/elements.
bool JSReceiver::IsSimpleEnum() {
Heap* heap = GetHeap();
for (Object* o = this;
o != heap->null_value();
o = JSObject::cast(o)->GetPrototype()) {
if (!o->IsJSObject()) return false;
JSObject* curr = JSObject::cast(o);
if (!curr->map()->instance_descriptors()->HasEnumCache()) return false;
ASSERT(!curr->HasNamedInterceptor());
ASSERT(!curr->HasIndexedInterceptor());
ASSERT(!curr->IsAccessCheckNeeded());
if (curr->NumberOfEnumElements() > 0) return false;
if (curr != this) {
FixedArray* curr_fixed_array =
FixedArray::cast(curr->map()->instance_descriptors()->GetEnumCache());
if (curr_fixed_array->length() > 0) return false;
}
}
return true;
}
int Map::NumberOfDescribedProperties(PropertyAttributes filter) {
int result = 0;
DescriptorArray* descs = instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
PropertyDetails details(descs->GetDetails(i));
if (descs->IsProperty(i) && (details.attributes() & filter) == 0) {
result++;
}
}
return result;
}
int Map::PropertyIndexFor(String* name) {
DescriptorArray* descs = instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
if (name->Equals(descs->GetKey(i)) && !descs->IsNullDescriptor(i)) {
return descs->GetFieldIndex(i);
}
}
return -1;
}
int Map::NextFreePropertyIndex() {
int max_index = -1;
DescriptorArray* descs = instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
if (descs->GetType(i) == FIELD) {
int current_index = descs->GetFieldIndex(i);
if (current_index > max_index) max_index = current_index;
}
}
return max_index + 1;
}
AccessorDescriptor* Map::FindAccessor(String* name) {
DescriptorArray* descs = instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
if (name->Equals(descs->GetKey(i)) && descs->GetType(i) == CALLBACKS) {
return descs->GetCallbacks(i);
}
}
return NULL;
}
void JSReceiver::LocalLookup(String* name, LookupResult* result) {
ASSERT(name->IsString());
Heap* heap = GetHeap();
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return result->NotFound();
ASSERT(proto->IsJSGlobalObject());
return JSReceiver::cast(proto)->LocalLookup(name, result);
}
if (IsJSProxy()) {
result->HandlerResult(JSProxy::cast(this));
return;
}
// Do not use inline caching if the object is a non-global object
// that requires access checks.
if (IsAccessCheckNeeded()) {
result->DisallowCaching();
}
JSObject* js_object = JSObject::cast(this);
// Check __proto__ before interceptor.
if (name->Equals(heap->Proto_symbol()) && !IsJSContextExtensionObject()) {
result->ConstantResult(js_object);
return;
}
// Check for lookup interceptor except when bootstrapping.
if (js_object->HasNamedInterceptor() &&
!heap->isolate()->bootstrapper()->IsActive()) {
result->InterceptorResult(js_object);
return;
}
js_object->LocalLookupRealNamedProperty(name, result);
}
void JSReceiver::Lookup(String* name, LookupResult* result) {
// Ecma-262 3rd 8.6.2.4
Heap* heap = GetHeap();
for (Object* current = this;
current != heap->null_value();
current = JSObject::cast(current)->GetPrototype()) {
JSReceiver::cast(current)->LocalLookup(name, result);
if (result->IsProperty()) return;
}
result->NotFound();
}
// Search object and it's prototype chain for callback properties.
void JSObject::LookupCallback(String* name, LookupResult* result) {
Heap* heap = GetHeap();
for (Object* current = this;
current != heap->null_value() && current->IsJSObject();
current = JSObject::cast(current)->GetPrototype()) {
JSObject::cast(current)->LocalLookupRealNamedProperty(name, result);
if (result->IsFound() && result->type() == CALLBACKS) return;
}
result->NotFound();
}
// Try to update an accessor in an elements dictionary. Return true if the
// update succeeded, and false otherwise.
static bool UpdateGetterSetterInDictionary(
SeededNumberDictionary* dictionary,
uint32_t index,
Object* getter,
Object* setter,
PropertyAttributes attributes) {
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Object* result = dictionary->ValueAt(entry);
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS && result->IsAccessorPair()) {
ASSERT(!details.IsDontDelete());
if (details.attributes() != attributes) {
dictionary->DetailsAtPut(entry,
PropertyDetails(attributes, CALLBACKS, index));
}
AccessorPair::cast(result)->SetComponents(getter, setter);
return true;
}
}
return false;
}
MaybeObject* JSObject::DefineElementAccessor(uint32_t index,
Object* getter,
Object* setter,
PropertyAttributes attributes) {
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
break;
case EXTERNAL_PIXEL_ELEMENTS:
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS:
// Ignore getters and setters on pixel and external array elements.
return GetHeap()->undefined_value();
case DICTIONARY_ELEMENTS:
if (UpdateGetterSetterInDictionary(element_dictionary(),
index,
getter,
setter,
attributes)) {
return GetHeap()->undefined_value();
}
break;
case NON_STRICT_ARGUMENTS_ELEMENTS: {
// Ascertain whether we have read-only properties or an existing
// getter/setter pair in an arguments elements dictionary backing
// store.
FixedArray* parameter_map = FixedArray::cast(elements());
uint32_t length = parameter_map->length();
Object* probe =
index < (length - 2) ? parameter_map->get(index + 2) : NULL;
if (probe == NULL || probe->IsTheHole()) {
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(arguments);
if (UpdateGetterSetterInDictionary(dictionary,
index,
getter,
setter,
attributes)) {
return GetHeap()->undefined_value();
}
}
}
break;
}
}
AccessorPair* accessors;
{ MaybeObject* maybe_accessors = GetHeap()->AllocateAccessorPair();
if (!maybe_accessors->To(&accessors)) return maybe_accessors;
}
accessors->SetComponents(getter, setter);
return SetElementCallback(index, accessors, attributes);
}
MaybeObject* JSObject::DefinePropertyAccessor(String* name,
Object* getter,
Object* setter,
PropertyAttributes attributes) {
// Lookup the name.
LookupResult result(GetHeap()->isolate());
LocalLookupRealNamedProperty(name, &result);
if (result.IsFound()) {
if (result.type() == CALLBACKS) {
ASSERT(!result.IsDontDelete());
Object* obj = result.GetCallbackObject();
// Need to preserve old getters/setters.
if (obj->IsAccessorPair()) {
AccessorPair* copy;
{ MaybeObject* maybe_copy =
AccessorPair::cast(obj)->CopyWithoutTransitions();
if (!maybe_copy->To(©)) return maybe_copy;
}
copy->SetComponents(getter, setter);
// Use set to update attributes.
return SetPropertyCallback(name, copy, attributes);
}
}
}
AccessorPair* accessors;
{ MaybeObject* maybe_accessors = GetHeap()->AllocateAccessorPair();
if (!maybe_accessors->To(&accessors)) return maybe_accessors;
}
accessors->SetComponents(getter, setter);
return SetPropertyCallback(name, accessors, attributes);
}
bool JSObject::CanSetCallback(String* name) {
ASSERT(!IsAccessCheckNeeded() ||
GetIsolate()->MayNamedAccess(this, name, v8::ACCESS_SET));
// Check if there is an API defined callback object which prohibits
// callback overwriting in this object or it's prototype chain.
// This mechanism is needed for instance in a browser setting, where
// certain accessors such as window.location should not be allowed
// to be overwritten because allowing overwriting could potentially
// cause security problems.
LookupResult callback_result(GetIsolate());
LookupCallback(name, &callback_result);
if (callback_result.IsProperty()) {
Object* obj = callback_result.GetCallbackObject();
if (obj->IsAccessorInfo() &&
AccessorInfo::cast(obj)->prohibits_overwriting()) {
return false;
}
}
return true;
}
MaybeObject* JSObject::SetElementCallback(uint32_t index,
Object* structure,
PropertyAttributes attributes) {
PropertyDetails details = PropertyDetails(attributes, CALLBACKS);
// Normalize elements to make this operation simple.
SeededNumberDictionary* dictionary;
{ MaybeObject* maybe_dictionary = NormalizeElements();
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
}
ASSERT(HasDictionaryElements() || HasDictionaryArgumentsElements());
// Update the dictionary with the new CALLBACKS property.
{ MaybeObject* maybe_dictionary = dictionary->Set(index, structure, details);
if (!maybe_dictionary->To(&dictionary)) return maybe_dictionary;
}
dictionary->set_requires_slow_elements();
// Update the dictionary backing store on the object.
if (elements()->map() == GetHeap()->non_strict_arguments_elements_map()) {
// Also delete any parameter alias.
//
// TODO(kmillikin): when deleting the last parameter alias we could
// switch to a direct backing store without the parameter map. This
// would allow GC of the context.
FixedArray* parameter_map = FixedArray::cast(elements());
if (index < static_cast<uint32_t>(parameter_map->length()) - 2) {
parameter_map->set(index + 2, GetHeap()->the_hole_value());
}
parameter_map->set(1, dictionary);
} else {
set_elements(dictionary);
}
return GetHeap()->undefined_value();
}
MaybeObject* JSObject::SetPropertyCallback(String* name,
Object* structure,
PropertyAttributes attributes) {
// Normalize object to make this operation simple.
{ MaybeObject* maybe_ok = NormalizeProperties(CLEAR_INOBJECT_PROPERTIES, 0);
if (maybe_ok->IsFailure()) return maybe_ok;
}
// For the global object allocate a new map to invalidate the global inline
// caches which have a global property cell reference directly in the code.
if (IsGlobalObject()) {
Map* new_map;
{ MaybeObject* maybe_new_map = map()->CopyDropDescriptors();
if (!maybe_new_map->To(&new_map)) return maybe_new_map;
}
set_map(new_map);
// When running crankshaft, changing the map is not enough. We
// need to deoptimize all functions that rely on this global
// object.
Deoptimizer::DeoptimizeGlobalObject(this);
}
// Update the dictionary with the new CALLBACKS property.
PropertyDetails details = PropertyDetails(attributes, CALLBACKS);
{ MaybeObject* maybe_ok = SetNormalizedProperty(name, structure, details);
if (maybe_ok->IsFailure()) return maybe_ok;
}
return GetHeap()->undefined_value();
}
void JSObject::DefineAccessor(Handle<JSObject> object,
Handle<String> name,
Handle<Object> getter,
Handle<Object> setter,
PropertyAttributes attributes) {
CALL_HEAP_FUNCTION_VOID(
object->GetIsolate(),
object->DefineAccessor(*name, *getter, *setter, attributes));
}
MaybeObject* JSObject::DefineAccessor(String* name,
Object* getter,
Object* setter,
PropertyAttributes attributes) {
Isolate* isolate = GetIsolate();
// Check access rights if needed.
if (IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(this, name, v8::ACCESS_SET)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_SET);
return isolate->heap()->undefined_value();
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return this;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->DefineAccessor(
name, getter, setter, attributes);
}
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc;
// Try to flatten before operating on the string.
name->TryFlatten();
if (!CanSetCallback(name)) return isolate->heap()->undefined_value();
uint32_t index = 0;
return name->AsArrayIndex(&index) ?
DefineElementAccessor(index, getter, setter, attributes) :
DefinePropertyAccessor(name, getter, setter, attributes);
}
MaybeObject* JSObject::DefineAccessor(AccessorInfo* info) {
Isolate* isolate = GetIsolate();
String* name = String::cast(info->name());
// Check access rights if needed.
if (IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(this, name, v8::ACCESS_SET)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_SET);
return isolate->heap()->undefined_value();
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return this;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->DefineAccessor(info);
}
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc;
// Try to flatten before operating on the string.
name->TryFlatten();
if (!CanSetCallback(name)) {
return isolate->heap()->undefined_value();
}
uint32_t index = 0;
bool is_element = name->AsArrayIndex(&index);
if (is_element) {
if (IsJSArray()) return isolate->heap()->undefined_value();
// Accessors overwrite previous callbacks (cf. with getters/setters).
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
break;
case EXTERNAL_PIXEL_ELEMENTS:
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS:
// Ignore getters and setters on pixel and external array
// elements.
return isolate->heap()->undefined_value();
case DICTIONARY_ELEMENTS:
break;
case NON_STRICT_ARGUMENTS_ELEMENTS:
UNIMPLEMENTED();
break;
}
{ MaybeObject* maybe_ok =
SetElementCallback(index, info, info->property_attributes());
if (maybe_ok->IsFailure()) return maybe_ok;
}
} else {
// Lookup the name.
LookupResult result(isolate);
LocalLookup(name, &result);
// ES5 forbids turning a property into an accessor if it's not
// configurable (that is IsDontDelete in ES3 and v8), see 8.6.1 (Table 5).
if (result.IsProperty() && (result.IsReadOnly() || result.IsDontDelete())) {
return isolate->heap()->undefined_value();
}
{ MaybeObject* maybe_ok =
SetPropertyCallback(name, info, info->property_attributes());
if (maybe_ok->IsFailure()) return maybe_ok;
}
}
return this;
}
Object* JSObject::LookupAccessor(String* name, AccessorComponent component) {
Heap* heap = GetHeap();
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc;
// Check access rights if needed.
if (IsAccessCheckNeeded() &&
!heap->isolate()->MayNamedAccess(this, name, v8::ACCESS_HAS)) {
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return heap->undefined_value();
}
// Make the lookup and include prototypes.
uint32_t index = 0;
if (name->AsArrayIndex(&index)) {
for (Object* obj = this;
obj != heap->null_value();
obj = JSObject::cast(obj)->GetPrototype()) {
JSObject* js_object = JSObject::cast(obj);
if (js_object->HasDictionaryElements()) {
SeededNumberDictionary* dictionary = js_object->element_dictionary();
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Object* element = dictionary->ValueAt(entry);
if (dictionary->DetailsAt(entry).type() == CALLBACKS &&
element->IsAccessorPair()) {
return AccessorPair::cast(element)->GetComponent(component);
}
}
}
}
} else {
for (Object* obj = this;
obj != heap->null_value();
obj = JSObject::cast(obj)->GetPrototype()) {
LookupResult result(heap->isolate());
JSObject::cast(obj)->LocalLookup(name, &result);
if (result.IsProperty()) {
if (result.IsReadOnly()) return heap->undefined_value();
if (result.type() == CALLBACKS) {
Object* obj = result.GetCallbackObject();
if (obj->IsAccessorPair()) {
return AccessorPair::cast(obj)->GetComponent(component);
}
}
}
}
}
return heap->undefined_value();
}
Object* JSObject::SlowReverseLookup(Object* value) {
if (HasFastProperties()) {
DescriptorArray* descs = map()->instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
if (descs->GetType(i) == FIELD) {
if (FastPropertyAt(descs->GetFieldIndex(i)) == value) {
return descs->GetKey(i);
}
} else if (descs->GetType(i) == CONSTANT_FUNCTION) {
if (descs->GetConstantFunction(i) == value) {
return descs->GetKey(i);
}
}
}
return GetHeap()->undefined_value();
} else {
return property_dictionary()->SlowReverseLookup(value);
}
}
MaybeObject* Map::CopyDropDescriptors() {
Heap* heap = GetHeap();
Object* result;
{ MaybeObject* maybe_result =
heap->AllocateMap(instance_type(), instance_size());
if (!maybe_result->ToObject(&result)) return maybe_result;
}
Map::cast(result)->set_prototype(prototype());
Map::cast(result)->set_constructor(constructor());
// Don't copy descriptors, so map transitions always remain a forest.
// If we retained the same descriptors we would have two maps
// pointing to the same transition which is bad because the garbage
// collector relies on being able to reverse pointers from transitions
// to maps. If properties need to be retained use CopyDropTransitions.
Map::cast(result)->clear_instance_descriptors();
// Please note instance_type and instance_size are set when allocated.
Map::cast(result)->set_inobject_properties(inobject_properties());
Map::cast(result)->set_unused_property_fields(unused_property_fields());
// If the map has pre-allocated properties always start out with a descriptor
// array describing these properties.
if (pre_allocated_property_fields() > 0) {
ASSERT(constructor()->IsJSFunction());
JSFunction* ctor = JSFunction::cast(constructor());
Object* descriptors;
{ MaybeObject* maybe_descriptors =
ctor->initial_map()->instance_descriptors()->RemoveTransitions();
if (!maybe_descriptors->ToObject(&descriptors)) return maybe_descriptors;
}
Map::cast(result)->set_instance_descriptors(
DescriptorArray::cast(descriptors));
Map::cast(result)->set_pre_allocated_property_fields(
pre_allocated_property_fields());
}
Map::cast(result)->set_bit_field(bit_field());
Map::cast(result)->set_bit_field2(bit_field2());
Map::cast(result)->set_bit_field3(bit_field3());
Map::cast(result)->set_is_shared(false);
Map::cast(result)->ClearCodeCache(heap);
return result;
}
MaybeObject* Map::CopyNormalized(PropertyNormalizationMode mode,
NormalizedMapSharingMode sharing) {
int new_instance_size = instance_size();
if (mode == CLEAR_INOBJECT_PROPERTIES) {
new_instance_size -= inobject_properties() * kPointerSize;
}
Object* result;
{ MaybeObject* maybe_result =
GetHeap()->AllocateMap(instance_type(), new_instance_size);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
if (mode != CLEAR_INOBJECT_PROPERTIES) {
Map::cast(result)->set_inobject_properties(inobject_properties());
}
Map::cast(result)->set_prototype(prototype());
Map::cast(result)->set_constructor(constructor());
Map::cast(result)->set_bit_field(bit_field());
Map::cast(result)->set_bit_field2(bit_field2());
Map::cast(result)->set_bit_field3(bit_field3());
Map::cast(result)->set_is_shared(sharing == SHARED_NORMALIZED_MAP);
#ifdef DEBUG
if (FLAG_verify_heap && Map::cast(result)->is_shared()) {
Map::cast(result)->SharedMapVerify();
}
#endif
return result;
}
MaybeObject* Map::CopyDropTransitions() {
Object* new_map;
{ MaybeObject* maybe_new_map = CopyDropDescriptors();
if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
}
Object* descriptors;
{ MaybeObject* maybe_descriptors =
instance_descriptors()->RemoveTransitions();
if (!maybe_descriptors->ToObject(&descriptors)) return maybe_descriptors;
}
cast(new_map)->set_instance_descriptors(DescriptorArray::cast(descriptors));
return new_map;
}
void Map::UpdateCodeCache(Handle<Map> map,
Handle<String> name,
Handle<Code> code) {
Isolate* isolate = map->GetIsolate();
CALL_HEAP_FUNCTION_VOID(isolate,
map->UpdateCodeCache(*name, *code));
}
MaybeObject* Map::UpdateCodeCache(String* name, Code* code) {
// Allocate the code cache if not present.
if (code_cache()->IsFixedArray()) {
Object* result;
{ MaybeObject* maybe_result = GetHeap()->AllocateCodeCache();
if (!maybe_result->ToObject(&result)) return maybe_result;
}
set_code_cache(result);
}
// Update the code cache.
return CodeCache::cast(code_cache())->Update(name, code);
}
Object* Map::FindInCodeCache(String* name, Code::Flags flags) {
// Do a lookup if a code cache exists.
if (!code_cache()->IsFixedArray()) {
return CodeCache::cast(code_cache())->Lookup(name, flags);
} else {
return GetHeap()->undefined_value();
}
}
int Map::IndexInCodeCache(Object* name, Code* code) {
// Get the internal index if a code cache exists.
if (!code_cache()->IsFixedArray()) {
return CodeCache::cast(code_cache())->GetIndex(name, code);
}
return -1;
}
void Map::RemoveFromCodeCache(String* name, Code* code, int index) {
// No GC is supposed to happen between a call to IndexInCodeCache and
// RemoveFromCodeCache so the code cache must be there.
ASSERT(!code_cache()->IsFixedArray());
CodeCache::cast(code_cache())->RemoveByIndex(name, code, index);
}
// An iterator over all map transitions in an descriptor array, reusing the map
// field of the contens array while it is running.
class IntrusiveMapTransitionIterator {
public:
explicit IntrusiveMapTransitionIterator(DescriptorArray* descriptor_array)
: descriptor_array_(descriptor_array) { }
void Start() {
ASSERT(!IsIterating());
if (HasContentArray()) *ContentHeader() = Smi::FromInt(0);
}
bool IsIterating() {
return HasContentArray() && (*ContentHeader())->IsSmi();
}
Map* Next() {
ASSERT(IsIterating());
FixedArray* contents = ContentArray();
// Attention, tricky index manipulation ahead: Every entry in the contents
// array consists of a value/details pair, so the index is typically even.
// An exception is made for CALLBACKS entries: An even index means we look
// at its getter, and an odd index means we look at its setter.
int index = Smi::cast(*ContentHeader())->value();
while (index < contents->length()) {
PropertyDetails details(Smi::cast(contents->get(index | 1)));
switch (details.type()) {
case MAP_TRANSITION:
case CONSTANT_TRANSITION:
case ELEMENTS_TRANSITION:
// We definitely have a map transition.
*ContentHeader() = Smi::FromInt(index + 2);
return static_cast<Map*>(contents->get(index));
case CALLBACKS: {
// We might have a map transition in a getter or in a setter.
AccessorPair* accessors =
static_cast<AccessorPair*>(contents->get(index & ~1));
Object* accessor =
((index & 1) == 0) ? accessors->getter() : accessors->setter();
index++;
if (accessor->IsMap()) {
*ContentHeader() = Smi::FromInt(index);
return static_cast<Map*>(accessor);
}
break;
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION:
case HANDLER:
case INTERCEPTOR:
case NULL_DESCRIPTOR:
// We definitely have no map transition.
index += 2;
break;
}
}
*ContentHeader() = descriptor_array_->GetHeap()->fixed_array_map();
return NULL;
}
private:
bool HasContentArray() {
return descriptor_array_-> length() > DescriptorArray::kContentArrayIndex;
}
FixedArray* ContentArray() {
Object* array = descriptor_array_->get(DescriptorArray::kContentArrayIndex);
return static_cast<FixedArray*>(array);
}
Object** ContentHeader() {
return HeapObject::RawField(ContentArray(), DescriptorArray::kMapOffset);
}
DescriptorArray* descriptor_array_;
};
// An iterator over all prototype transitions, reusing the map field of the
// underlying array while it is running.
class IntrusivePrototypeTransitionIterator {
public:
explicit IntrusivePrototypeTransitionIterator(FixedArray* proto_trans)
: proto_trans_(proto_trans) { }
void Start() {
ASSERT(!IsIterating());
if (HasTransitions()) *Header() = Smi::FromInt(0);
}
bool IsIterating() {
return HasTransitions() && (*Header())->IsSmi();
}
Map* Next() {
ASSERT(IsIterating());
int transitionNumber = Smi::cast(*Header())->value();
if (transitionNumber < NumberOfTransitions()) {
*Header() = Smi::FromInt(transitionNumber + 1);
return GetTransition(transitionNumber);
}
*Header() = proto_trans_->GetHeap()->fixed_array_map();
return NULL;
}
private:
bool HasTransitions() {
return proto_trans_->length() >= Map::kProtoTransitionHeaderSize;
}
Object** Header() {
return HeapObject::RawField(proto_trans_, FixedArray::kMapOffset);
}
int NumberOfTransitions() {
Object* num = proto_trans_->get(Map::kProtoTransitionNumberOfEntriesOffset);
return Smi::cast(num)->value();
}
Map* GetTransition(int transitionNumber) {
return Map::cast(proto_trans_->get(IndexFor(transitionNumber)));
}
int IndexFor(int transitionNumber) {
return Map::kProtoTransitionHeaderSize +
Map::kProtoTransitionMapOffset +
transitionNumber * Map::kProtoTransitionElementsPerEntry;
}
FixedArray* proto_trans_;
};
// To traverse the transition tree iteratively, we have to store two kinds of
// information in a map: The parent map in the traversal and which children of a
// node have already been visited. To do this without additional memory, we
// temporarily reuse two maps with known values:
//
// (1) The map of the map temporarily holds the parent, and is restored to the
// meta map afterwards.
//
// (2) The info which children have already been visited depends on which part
// of the map we currently iterate:
//
// (a) If we currently follow normal map transitions, we temporarily store
// the current index in the map of the FixedArray of the desciptor
// array's contents, and restore it to the fixed array map afterwards.
// Note that a single descriptor can have 0, 1, or 2 transitions.
//
// (b) If we currently follow prototype transitions, we temporarily store
// the current index in the map of the FixedArray holding the prototype
// transitions, and restore it to the fixed array map afterwards.
//
// Note that the child iterator is just a concatenation of two iterators: One
// iterating over map transitions and one iterating over prototype transisitons.
class TraversableMap : public Map {
public:
// Record the parent in the traversal within this map. Note that this destroys
// this map's map!
void SetParent(TraversableMap* parent) { set_map_no_write_barrier(parent); }
// Reset the current map's map, returning the parent previously stored in it.
TraversableMap* GetAndResetParent() {
TraversableMap* old_parent = static_cast<TraversableMap*>(map());
set_map_no_write_barrier(GetHeap()->meta_map());
return old_parent;
}
// Start iterating over this map's children, possibly destroying a FixedArray
// map (see explanation above).
void ChildIteratorStart() {
IntrusiveMapTransitionIterator(instance_descriptors()).Start();
IntrusivePrototypeTransitionIterator(
unchecked_prototype_transitions()).Start();
}
// If we have an unvisited child map, return that one and advance. If we have
// none, return NULL and reset any destroyed FixedArray maps.
TraversableMap* ChildIteratorNext() {
IntrusiveMapTransitionIterator descriptor_iterator(instance_descriptors());
if (descriptor_iterator.IsIterating()) {
Map* next = descriptor_iterator.Next();
if (next != NULL) return static_cast<TraversableMap*>(next);
}
IntrusivePrototypeTransitionIterator
proto_iterator(unchecked_prototype_transitions());
if (proto_iterator.IsIterating()) {
Map* next = proto_iterator.Next();
if (next != NULL) return static_cast<TraversableMap*>(next);
}
return NULL;
}
};
// Traverse the transition tree in postorder without using the C++ stack by
// doing pointer reversal.
void Map::TraverseTransitionTree(TraverseCallback callback, void* data) {
TraversableMap* current = static_cast<TraversableMap*>(this);
current->ChildIteratorStart();
while (true) {
TraversableMap* child = current->ChildIteratorNext();
if (child != NULL) {
child->ChildIteratorStart();
child->SetParent(current);
current = child;
} else {
TraversableMap* parent = current->GetAndResetParent();
callback(current, data);
if (current == this) break;
current = parent;
}
}
}
MaybeObject* CodeCache::Update(String* name, Code* code) {
// The number of monomorphic stubs for normal load/store/call IC's can grow to
// a large number and therefore they need to go into a hash table. They are
// used to load global properties from cells.
if (code->type() == NORMAL) {
// Make sure that a hash table is allocated for the normal load code cache.
if (normal_type_cache()->IsUndefined()) {
Object* result;
{ MaybeObject* maybe_result =
CodeCacheHashTable::Allocate(CodeCacheHashTable::kInitialSize);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
set_normal_type_cache(result);
}
return UpdateNormalTypeCache(name, code);
} else {
ASSERT(default_cache()->IsFixedArray());
return UpdateDefaultCache(name, code);
}
}
MaybeObject* CodeCache::UpdateDefaultCache(String* name, Code* code) {
// When updating the default code cache we disregard the type encoded in the
// flags. This allows call constant stubs to overwrite call field
// stubs, etc.
Code::Flags flags = Code::RemoveTypeFromFlags(code->flags());
// First check whether we can update existing code cache without
// extending it.
FixedArray* cache = default_cache();
int length = cache->length();
int deleted_index = -1;
for (int i = 0; i < length; i += kCodeCacheEntrySize) {
Object* key = cache->get(i);
if (key->IsNull()) {
if (deleted_index < 0) deleted_index = i;
continue;
}
if (key->IsUndefined()) {
if (deleted_index >= 0) i = deleted_index;
cache->set(i + kCodeCacheEntryNameOffset, name);
cache->set(i + kCodeCacheEntryCodeOffset, code);
return this;
}
if (name->Equals(String::cast(key))) {
Code::Flags found =
Code::cast(cache->get(i + kCodeCacheEntryCodeOffset))->flags();
if (Code::RemoveTypeFromFlags(found) == flags) {
cache->set(i + kCodeCacheEntryCodeOffset, code);
return this;
}
}
}
// Reached the end of the code cache. If there were deleted
// elements, reuse the space for the first of them.
if (deleted_index >= 0) {
cache->set(deleted_index + kCodeCacheEntryNameOffset, name);
cache->set(deleted_index + kCodeCacheEntryCodeOffset, code);
return this;
}
// Extend the code cache with some new entries (at least one). Must be a
// multiple of the entry size.
int new_length = length + ((length >> 1)) + kCodeCacheEntrySize;
new_length = new_length - new_length % kCodeCacheEntrySize;
ASSERT((new_length % kCodeCacheEntrySize) == 0);
Object* result;
{ MaybeObject* maybe_result = cache->CopySize(new_length);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
// Add the (name, code) pair to the new cache.
cache = FixedArray::cast(result);
cache->set(length + kCodeCacheEntryNameOffset, name);
cache->set(length + kCodeCacheEntryCodeOffset, code);
set_default_cache(cache);
return this;
}
MaybeObject* CodeCache::UpdateNormalTypeCache(String* name, Code* code) {
// Adding a new entry can cause a new cache to be allocated.
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
Object* new_cache;
{ MaybeObject* maybe_new_cache = cache->Put(name, code);
if (!maybe_new_cache->ToObject(&new_cache)) return maybe_new_cache;
}
set_normal_type_cache(new_cache);
return this;
}
Object* CodeCache::Lookup(String* name, Code::Flags flags) {
if (Code::ExtractTypeFromFlags(flags) == NORMAL) {
return LookupNormalTypeCache(name, flags);
} else {
return LookupDefaultCache(name, flags);
}
}
Object* CodeCache::LookupDefaultCache(String* name, Code::Flags flags) {
FixedArray* cache = default_cache();
int length = cache->length();
for (int i = 0; i < length; i += kCodeCacheEntrySize) {
Object* key = cache->get(i + kCodeCacheEntryNameOffset);
// Skip deleted elements.
if (key->IsNull()) continue;
if (key->IsUndefined()) return key;
if (name->Equals(String::cast(key))) {
Code* code = Code::cast(cache->get(i + kCodeCacheEntryCodeOffset));
if (code->flags() == flags) {
return code;
}
}
}
return GetHeap()->undefined_value();
}
Object* CodeCache::LookupNormalTypeCache(String* name, Code::Flags flags) {
if (!normal_type_cache()->IsUndefined()) {
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
return cache->Lookup(name, flags);
} else {
return GetHeap()->undefined_value();
}
}
int CodeCache::GetIndex(Object* name, Code* code) {
if (code->type() == NORMAL) {
if (normal_type_cache()->IsUndefined()) return -1;
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
return cache->GetIndex(String::cast(name), code->flags());
}
FixedArray* array = default_cache();
int len = array->length();
for (int i = 0; i < len; i += kCodeCacheEntrySize) {
if (array->get(i + kCodeCacheEntryCodeOffset) == code) return i + 1;
}
return -1;
}
void CodeCache::RemoveByIndex(Object* name, Code* code, int index) {
if (code->type() == NORMAL) {
ASSERT(!normal_type_cache()->IsUndefined());
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
ASSERT(cache->GetIndex(String::cast(name), code->flags()) == index);
cache->RemoveByIndex(index);
} else {
FixedArray* array = default_cache();
ASSERT(array->length() >= index && array->get(index)->IsCode());
// Use null instead of undefined for deleted elements to distinguish
// deleted elements from unused elements. This distinction is used
// when looking up in the cache and when updating the cache.
ASSERT_EQ(1, kCodeCacheEntryCodeOffset - kCodeCacheEntryNameOffset);
array->set_null(index - 1); // Name.
array->set_null(index); // Code.
}
}
// The key in the code cache hash table consists of the property name and the
// code object. The actual match is on the name and the code flags. If a key
// is created using the flags and not a code object it can only be used for
// lookup not to create a new entry.
class CodeCacheHashTableKey : public HashTableKey {
public:
CodeCacheHashTableKey(String* name, Code::Flags flags)
: name_(name), flags_(flags), code_(NULL) { }
CodeCacheHashTableKey(String* name, Code* code)
: name_(name),
flags_(code->flags()),
code_(code) { }
bool IsMatch(Object* other) {
if (!other->IsFixedArray()) return false;
FixedArray* pair = FixedArray::cast(other);
String* name = String::cast(pair->get(0));
Code::Flags flags = Code::cast(pair->get(1))->flags();
if (flags != flags_) {
return false;
}
return name_->Equals(name);
}
static uint32_t NameFlagsHashHelper(String* name, Code::Flags flags) {
return name->Hash() ^ flags;
}
uint32_t Hash() { return NameFlagsHashHelper(name_, flags_); }
uint32_t HashForObject(Object* obj) {
FixedArray* pair = FixedArray::cast(obj);
String* name = String::cast(pair->get(0));
Code* code = Code::cast(pair->get(1));
return NameFlagsHashHelper(name, code->flags());
}
MUST_USE_RESULT MaybeObject* AsObject() {
ASSERT(code_ != NULL);
Object* obj;
{ MaybeObject* maybe_obj = code_->GetHeap()->AllocateFixedArray(2);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* pair = FixedArray::cast(obj);
pair->set(0, name_);
pair->set(1, code_);
return pair;
}
private:
String* name_;
Code::Flags flags_;
// TODO(jkummerow): We should be able to get by without this.
Code* code_;
};
Object* CodeCacheHashTable::Lookup(String* name, Code::Flags flags) {
CodeCacheHashTableKey key(name, flags);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
MaybeObject* CodeCacheHashTable::Put(String* name, Code* code) {
CodeCacheHashTableKey key(name, code);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
// Don't use |this|, as the table might have grown.
CodeCacheHashTable* cache = reinterpret_cast<CodeCacheHashTable*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
Object* k;
{ MaybeObject* maybe_k = key.AsObject();
if (!maybe_k->ToObject(&k)) return maybe_k;
}
cache->set(EntryToIndex(entry), k);
cache->set(EntryToIndex(entry) + 1, code);
cache->ElementAdded();
return cache;
}
int CodeCacheHashTable::GetIndex(String* name, Code::Flags flags) {
CodeCacheHashTableKey key(name, flags);
int entry = FindEntry(&key);
return (entry == kNotFound) ? -1 : entry;
}
void CodeCacheHashTable::RemoveByIndex(int index) {
ASSERT(index >= 0);
Heap* heap = GetHeap();
set(EntryToIndex(index), heap->the_hole_value());
set(EntryToIndex(index) + 1, heap->the_hole_value());
ElementRemoved();
}
void PolymorphicCodeCache::Update(Handle<PolymorphicCodeCache> cache,
MapHandleList* maps,
Code::Flags flags,
Handle<Code> code) {
Isolate* isolate = cache->GetIsolate();
CALL_HEAP_FUNCTION_VOID(isolate, cache->Update(maps, flags, *code));
}
MaybeObject* PolymorphicCodeCache::Update(MapHandleList* maps,
Code::Flags flags,
Code* code) {
// Initialize cache if necessary.
if (cache()->IsUndefined()) {
Object* result;
{ MaybeObject* maybe_result =
PolymorphicCodeCacheHashTable::Allocate(
PolymorphicCodeCacheHashTable::kInitialSize);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
set_cache(result);
} else {
// This entry shouldn't be contained in the cache yet.
ASSERT(PolymorphicCodeCacheHashTable::cast(cache())
->Lookup(maps, flags)->IsUndefined());
}
PolymorphicCodeCacheHashTable* hash_table =
PolymorphicCodeCacheHashTable::cast(cache());
Object* new_cache;
{ MaybeObject* maybe_new_cache = hash_table->Put(maps, flags, code);
if (!maybe_new_cache->ToObject(&new_cache)) return maybe_new_cache;
}
set_cache(new_cache);
return this;
}
Handle<Object> PolymorphicCodeCache::Lookup(MapHandleList* maps,
Code::Flags flags) {
if (!cache()->IsUndefined()) {
PolymorphicCodeCacheHashTable* hash_table =
PolymorphicCodeCacheHashTable::cast(cache());
return Handle<Object>(hash_table->Lookup(maps, flags));
} else {
return GetIsolate()->factory()->undefined_value();
}
}
// Despite their name, object of this class are not stored in the actual
// hash table; instead they're temporarily used for lookups. It is therefore
// safe to have a weak (non-owning) pointer to a MapList as a member field.
class PolymorphicCodeCacheHashTableKey : public HashTableKey {
public:
// Callers must ensure that |maps| outlives the newly constructed object.
PolymorphicCodeCacheHashTableKey(MapHandleList* maps, int code_flags)
: maps_(maps),
code_flags_(code_flags) {}
bool IsMatch(Object* other) {
MapHandleList other_maps(kDefaultListAllocationSize);
int other_flags;
FromObject(other, &other_flags, &other_maps);
if (code_flags_ != other_flags) return false;
if (maps_->length() != other_maps.length()) return false;
// Compare just the hashes first because it's faster.
int this_hash = MapsHashHelper(maps_, code_flags_);
int other_hash = MapsHashHelper(&other_maps, other_flags);
if (this_hash != other_hash) return false;
// Full comparison: for each map in maps_, look for an equivalent map in
// other_maps. This implementation is slow, but probably good enough for
// now because the lists are short (<= 4 elements currently).
for (int i = 0; i < maps_->length(); ++i) {
bool match_found = false;
for (int j = 0; j < other_maps.length(); ++j) {
if (*(maps_->at(i)) == *(other_maps.at(j))) {
match_found = true;
break;
}
}
if (!match_found) return false;
}
return true;
}
static uint32_t MapsHashHelper(MapHandleList* maps, int code_flags) {
uint32_t hash = code_flags;
for (int i = 0; i < maps->length(); ++i) {
hash ^= maps->at(i)->Hash();
}
return hash;
}
uint32_t Hash() {
return MapsHashHelper(maps_, code_flags_);
}
uint32_t HashForObject(Object* obj) {
MapHandleList other_maps(kDefaultListAllocationSize);
int other_flags;
FromObject(obj, &other_flags, &other_maps);
return MapsHashHelper(&other_maps, other_flags);
}
MUST_USE_RESULT MaybeObject* AsObject() {
Object* obj;
// The maps in |maps_| must be copied to a newly allocated FixedArray,
// both because the referenced MapList is short-lived, and because C++
// objects can't be stored in the heap anyway.
{ MaybeObject* maybe_obj =
HEAP->AllocateUninitializedFixedArray(maps_->length() + 1);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* list = FixedArray::cast(obj);
list->set(0, Smi::FromInt(code_flags_));
for (int i = 0; i < maps_->length(); ++i) {
list->set(i + 1, *maps_->at(i));
}
return list;
}
private:
static MapHandleList* FromObject(Object* obj,
int* code_flags,
MapHandleList* maps) {
FixedArray* list = FixedArray::cast(obj);
maps->Rewind(0);
*code_flags = Smi::cast(list->get(0))->value();
for (int i = 1; i < list->length(); ++i) {
maps->Add(Handle<Map>(Map::cast(list->get(i))));
}
return maps;
}
MapHandleList* maps_; // weak.
int code_flags_;
static const int kDefaultListAllocationSize = kMaxKeyedPolymorphism + 1;
};
Object* PolymorphicCodeCacheHashTable::Lookup(MapHandleList* maps,
int code_flags) {
PolymorphicCodeCacheHashTableKey key(maps, code_flags);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
MaybeObject* PolymorphicCodeCacheHashTable::Put(MapHandleList* maps,
int code_flags,
Code* code) {
PolymorphicCodeCacheHashTableKey key(maps, code_flags);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
PolymorphicCodeCacheHashTable* cache =
reinterpret_cast<PolymorphicCodeCacheHashTable*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
{ MaybeObject* maybe_obj = key.AsObject();
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
cache->set(EntryToIndex(entry), obj);
cache->set(EntryToIndex(entry) + 1, code);
cache->ElementAdded();
return cache;
}
MaybeObject* FixedArray::AddKeysFromJSArray(JSArray* array) {
ElementsAccessor* accessor = array->GetElementsAccessor();
MaybeObject* maybe_result =
accessor->AddElementsToFixedArray(array, array, this);
FixedArray* result;
if (!maybe_result->To<FixedArray>(&result)) return maybe_result;
#ifdef DEBUG
if (FLAG_enable_slow_asserts) {
for (int i = 0; i < result->length(); i++) {
Object* current = result->get(i);
ASSERT(current->IsNumber() || current->IsString());
}
}
#endif
return result;
}
MaybeObject* FixedArray::UnionOfKeys(FixedArray* other) {
ElementsAccessor* accessor = ElementsAccessor::ForArray(other);
MaybeObject* maybe_result =
accessor->AddElementsToFixedArray(NULL, NULL, this, other);
FixedArray* result;
if (!maybe_result->To<FixedArray>(&result)) return maybe_result;
#ifdef DEBUG
if (FLAG_enable_slow_asserts) {
for (int i = 0; i < result->length(); i++) {
Object* current = result->get(i);
ASSERT(current->IsNumber() || current->IsString());
}
}
#endif
return result;
}
MaybeObject* FixedArray::CopySize(int new_length) {
Heap* heap = GetHeap();
if (new_length == 0) return heap->empty_fixed_array();
Object* obj;
{ MaybeObject* maybe_obj = heap->AllocateFixedArray(new_length);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* result = FixedArray::cast(obj);
// Copy the content
AssertNoAllocation no_gc;
int len = length();
if (new_length < len) len = new_length;
// We are taking the map from the old fixed array so the map is sure to
// be an immortal immutable object.
result->set_map_no_write_barrier(map());
WriteBarrierMode mode = result->GetWriteBarrierMode(no_gc);
for (int i = 0; i < len; i++) {
result->set(i, get(i), mode);
}
return result;
}
void FixedArray::CopyTo(int pos, FixedArray* dest, int dest_pos, int len) {
AssertNoAllocation no_gc;
WriteBarrierMode mode = dest->GetWriteBarrierMode(no_gc);
for (int index = 0; index < len; index++) {
dest->set(dest_pos+index, get(pos+index), mode);
}
}
#ifdef DEBUG
bool FixedArray::IsEqualTo(FixedArray* other) {
if (length() != other->length()) return false;
for (int i = 0 ; i < length(); ++i) {
if (get(i) != other->get(i)) return false;
}
return true;
}
#endif
MaybeObject* DescriptorArray::Allocate(int number_of_descriptors) {
Heap* heap = Isolate::Current()->heap();
if (number_of_descriptors == 0) {
return heap->empty_descriptor_array();
}
// Allocate the array of keys.
Object* array;
{ MaybeObject* maybe_array =
heap->AllocateFixedArray(ToKeyIndex(number_of_descriptors));
if (!maybe_array->ToObject(&array)) return maybe_array;
}
// Do not use DescriptorArray::cast on incomplete object.
FixedArray* result = FixedArray::cast(array);
// Allocate the content array and set it in the descriptor array.
{ MaybeObject* maybe_array =
heap->AllocateFixedArray(number_of_descriptors << 1);
if (!maybe_array->ToObject(&array)) return maybe_array;
}
result->set(kBitField3StorageIndex, Smi::FromInt(0));
result->set(kContentArrayIndex, array);
result->set(kEnumerationIndexIndex,
Smi::FromInt(PropertyDetails::kInitialIndex));
return result;
}
void DescriptorArray::SetEnumCache(FixedArray* bridge_storage,
FixedArray* new_cache,
Object* new_index_cache) {
ASSERT(bridge_storage->length() >= kEnumCacheBridgeLength);
ASSERT(new_index_cache->IsSmi() || new_index_cache->IsFixedArray());
if (HasEnumCache()) {
FixedArray::cast(get(kEnumerationIndexIndex))->
set(kEnumCacheBridgeCacheIndex, new_cache);
FixedArray::cast(get(kEnumerationIndexIndex))->
set(kEnumCacheBridgeIndicesCacheIndex, new_index_cache);
} else {
if (IsEmpty()) return; // Do nothing for empty descriptor array.
FixedArray::cast(bridge_storage)->
set(kEnumCacheBridgeCacheIndex, new_cache);
FixedArray::cast(bridge_storage)->
set(kEnumCacheBridgeIndicesCacheIndex, new_index_cache);
NoWriteBarrierSet(FixedArray::cast(bridge_storage),
kEnumCacheBridgeEnumIndex,
get(kEnumerationIndexIndex));
set(kEnumerationIndexIndex, bridge_storage);
}
}
static bool InsertionPointFound(String* key1, String* key2) {
return key1->Hash() > key2->Hash() || key1 == key2;
}
void DescriptorArray::CopyFrom(Handle<DescriptorArray> dst,
int dst_index,
Handle<DescriptorArray> src,
int src_index,
const WhitenessWitness& witness) {
CALL_HEAP_FUNCTION_VOID(dst->GetIsolate(),
dst->CopyFrom(dst_index, *src, src_index, witness));
}
MaybeObject* DescriptorArray::CopyFrom(int dst_index,
DescriptorArray* src,
int src_index,
const WhitenessWitness& witness) {
Object* value = src->GetValue(src_index);
PropertyDetails details(src->GetDetails(src_index));
if (details.type() == CALLBACKS && value->IsAccessorPair()) {
MaybeObject* maybe_copy =
AccessorPair::cast(value)->CopyWithoutTransitions();
if (!maybe_copy->To(&value)) return maybe_copy;
}
Descriptor desc(src->GetKey(src_index), value, details);
Set(dst_index, &desc, witness);
return this;
}
MaybeObject* DescriptorArray::CopyInsert(Descriptor* descriptor,
TransitionFlag transition_flag) {
// Transitions are only kept when inserting another transition.
// This precondition is not required by this function's implementation, but
// is currently required by the semantics of maps, so we check it.
// Conversely, we filter after replacing, so replacing a transition and
// removing all other transitions is not supported.
bool remove_transitions = transition_flag == REMOVE_TRANSITIONS;
ASSERT(remove_transitions == !descriptor->ContainsTransition());
ASSERT(descriptor->GetDetails().type() != NULL_DESCRIPTOR);
// Ensure the key is a symbol.
{ MaybeObject* maybe_result = descriptor->KeyToSymbol();
if (maybe_result->IsFailure()) return maybe_result;
}
int new_size = 0;
for (int i = 0; i < number_of_descriptors(); i++) {
if (IsNullDescriptor(i)) continue;
if (remove_transitions && IsTransitionOnly(i)) continue;
new_size++;
}
// If key is in descriptor, we replace it in-place when filtering.
// Count a null descriptor for key as inserted, not replaced.
int index = Search(descriptor->GetKey());
const bool replacing = (index != kNotFound);
bool keep_enumeration_index = false;
if (replacing) {
// We are replacing an existing descriptor. We keep the enumeration
// index of a visible property.
PropertyType t = PropertyDetails(GetDetails(index)).type();
if (t == CONSTANT_FUNCTION ||
t == FIELD ||
t == CALLBACKS ||
t == INTERCEPTOR) {
keep_enumeration_index = true;
} else if (remove_transitions) {
// Replaced descriptor has been counted as removed if it is
// a transition that will be replaced. Adjust count in this case.
++new_size;
}
} else {
++new_size;
}
DescriptorArray* new_descriptors;
{ MaybeObject* maybe_result = Allocate(new_size);
if (!maybe_result->To(&new_descriptors)) return maybe_result;
}
DescriptorArray::WhitenessWitness witness(new_descriptors);
// Set the enumeration index in the descriptors and set the enumeration index
// in the result.
int enumeration_index = NextEnumerationIndex();
if (!descriptor->ContainsTransition()) {
if (keep_enumeration_index) {
descriptor->SetEnumerationIndex(
PropertyDetails(GetDetails(index)).index());
} else {
descriptor->SetEnumerationIndex(enumeration_index);
++enumeration_index;
}
}
new_descriptors->SetNextEnumerationIndex(enumeration_index);
// Copy the descriptors, filtering out transitions and null descriptors,
// and inserting or replacing a descriptor.
int to_index = 0;
int insertion_index = -1;
int from_index = 0;
while (from_index < number_of_descriptors()) {
if (insertion_index < 0 &&
InsertionPointFound(GetKey(from_index), descriptor->GetKey())) {
insertion_index = to_index++;
if (replacing) from_index++;
} else {
if (!(IsNullDescriptor(from_index) ||
(remove_transitions && IsTransitionOnly(from_index)))) {
MaybeObject* copy_result =
new_descriptors->CopyFrom(to_index++, this, from_index, witness);
if (copy_result->IsFailure()) return copy_result;
}
from_index++;
}
}
if (insertion_index < 0) insertion_index = to_index++;
new_descriptors->Set(insertion_index, descriptor, witness);
ASSERT(to_index == new_descriptors->number_of_descriptors());
SLOW_ASSERT(new_descriptors->IsSortedNoDuplicates());
return new_descriptors;
}
MaybeObject* DescriptorArray::RemoveTransitions() {
// Allocate the new descriptor array.
int new_number_of_descriptors = 0;
for (int i = 0; i < number_of_descriptors(); i++) {
if (IsProperty(i)) new_number_of_descriptors++;
}
DescriptorArray* new_descriptors;
{ MaybeObject* maybe_result = Allocate(new_number_of_descriptors);
if (!maybe_result->To(&new_descriptors)) return maybe_result;
}
// Copy the content.
DescriptorArray::WhitenessWitness witness(new_descriptors);
int next_descriptor = 0;
for (int i = 0; i < number_of_descriptors(); i++) {
if (IsProperty(i)) {
MaybeObject* copy_result =
new_descriptors->CopyFrom(next_descriptor++, this, i, witness);
if (copy_result->IsFailure()) return copy_result;
}
}
ASSERT(next_descriptor == new_descriptors->number_of_descriptors());
return new_descriptors;
}
void DescriptorArray::SortUnchecked(const WhitenessWitness& witness) {
// In-place heap sort.
int len = number_of_descriptors();
// Bottom-up max-heap construction.
// Index of the last node with children
const int max_parent_index = (len / 2) - 1;
for (int i = max_parent_index; i >= 0; --i) {
int parent_index = i;
const uint32_t parent_hash = GetKey(i)->Hash();
while (parent_index <= max_parent_index) {
int child_index = 2 * parent_index + 1;
uint32_t child_hash = GetKey(child_index)->Hash();
if (child_index + 1 < len) {
uint32_t right_child_hash = GetKey(child_index + 1)->Hash();
if (right_child_hash > child_hash) {
child_index++;
child_hash = right_child_hash;
}
}
if (child_hash <= parent_hash) break;
NoIncrementalWriteBarrierSwapDescriptors(parent_index, child_index);
// Now element at child_index could be < its children.
parent_index = child_index; // parent_hash remains correct.
}
}
// Extract elements and create sorted array.
for (int i = len - 1; i > 0; --i) {
// Put max element at the back of the array.
NoIncrementalWriteBarrierSwapDescriptors(0, i);
// Shift down the new top element.
int parent_index = 0;
const uint32_t parent_hash = GetKey(parent_index)->Hash();
const int max_parent_index = (i / 2) - 1;
while (parent_index <= max_parent_index) {
int child_index = parent_index * 2 + 1;
uint32_t child_hash = GetKey(child_index)->Hash();
if (child_index + 1 < i) {
uint32_t right_child_hash = GetKey(child_index + 1)->Hash();
if (right_child_hash > child_hash) {
child_index++;
child_hash = right_child_hash;
}
}
if (child_hash <= parent_hash) break;
NoIncrementalWriteBarrierSwapDescriptors(parent_index, child_index);
parent_index = child_index;
}
}
}
void DescriptorArray::Sort(const WhitenessWitness& witness) {
SortUnchecked(witness);
SLOW_ASSERT(IsSortedNoDuplicates());
}
int DescriptorArray::BinarySearch(String* name, int low, int high) {
uint32_t hash = name->Hash();
while (low <= high) {
int mid = (low + high) / 2;
String* mid_name = GetKey(mid);
uint32_t mid_hash = mid_name->Hash();
if (mid_hash > hash) {
high = mid - 1;
continue;
}
if (mid_hash < hash) {
low = mid + 1;
continue;
}
// Found an element with the same hash-code.
ASSERT(hash == mid_hash);
// There might be more, so we find the first one and
// check them all to see if we have a match.
if (name == mid_name && !is_null_descriptor(mid)) return mid;
while ((mid > low) && (GetKey(mid - 1)->Hash() == hash)) mid--;
for (; (mid <= high) && (GetKey(mid)->Hash() == hash); mid++) {
if (GetKey(mid)->Equals(name) && !is_null_descriptor(mid)) return mid;
}
break;
}
return kNotFound;
}
int DescriptorArray::LinearSearch(String* name, int len) {
uint32_t hash = name->Hash();
for (int number = 0; number < len; number++) {
String* entry = GetKey(number);
if ((entry->Hash() == hash) &&
name->Equals(entry) &&
!is_null_descriptor(number)) {
return number;
}
}
return kNotFound;
}
MaybeObject* AccessorPair::CopyWithoutTransitions() {
Heap* heap = GetHeap();
AccessorPair* copy;
{ MaybeObject* maybe_copy = heap->AllocateAccessorPair();
if (!maybe_copy->To(©)) return maybe_copy;
}
copy->set_getter(getter()->IsMap() ? heap->the_hole_value() : getter());
copy->set_setter(setter()->IsMap() ? heap->the_hole_value() : setter());
return copy;
}
Object* AccessorPair::GetComponent(AccessorComponent component) {
Object* accessor = (component == ACCESSOR_GETTER) ? getter() : setter();
return accessor->IsTheHole() ? GetHeap()->undefined_value() : accessor;
}
MaybeObject* DeoptimizationInputData::Allocate(int deopt_entry_count,
PretenureFlag pretenure) {
ASSERT(deopt_entry_count > 0);
return HEAP->AllocateFixedArray(LengthFor(deopt_entry_count),
pretenure);
}
MaybeObject* DeoptimizationOutputData::Allocate(int number_of_deopt_points,
PretenureFlag pretenure) {
if (number_of_deopt_points == 0) return HEAP->empty_fixed_array();
return HEAP->AllocateFixedArray(LengthOfFixedArray(number_of_deopt_points),
pretenure);
}
#ifdef DEBUG
bool DescriptorArray::IsEqualTo(DescriptorArray* other) {
if (IsEmpty()) return other->IsEmpty();
if (other->IsEmpty()) return false;
if (length() != other->length()) return false;
for (int i = 0; i < length(); ++i) {
if (get(i) != other->get(i) && i != kContentArrayIndex) return false;
}
return GetContentArray()->IsEqualTo(other->GetContentArray());
}
#endif
bool String::LooksValid() {
if (!Isolate::Current()->heap()->Contains(this)) return false;
return true;
}
String::FlatContent String::GetFlatContent() {
int length = this->length();
StringShape shape(this);
String* string = this;
int offset = 0;
if (shape.representation_tag() == kConsStringTag) {
ConsString* cons = ConsString::cast(string);
if (cons->second()->length() != 0) {
return FlatContent();
}
string = cons->first();
shape = StringShape(string);
}
if (shape.representation_tag() == kSlicedStringTag) {
SlicedString* slice = SlicedString::cast(string);
offset = slice->offset();
string = slice->parent();
shape = StringShape(string);
ASSERT(shape.representation_tag() != kConsStringTag &&
shape.representation_tag() != kSlicedStringTag);
}
if (shape.encoding_tag() == kAsciiStringTag) {
const char* start;
if (shape.representation_tag() == kSeqStringTag) {
start = SeqAsciiString::cast(string)->GetChars();
} else {
start = ExternalAsciiString::cast(string)->GetChars();
}
return FlatContent(Vector<const char>(start + offset, length));
} else {
ASSERT(shape.encoding_tag() == kTwoByteStringTag);
const uc16* start;
if (shape.representation_tag() == kSeqStringTag) {
start = SeqTwoByteString::cast(string)->GetChars();
} else {
start = ExternalTwoByteString::cast(string)->GetChars();
}
return FlatContent(Vector<const uc16>(start + offset, length));
}
}
SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
RobustnessFlag robust_flag,
int offset,
int length,
int* length_return) {
if (robust_flag == ROBUST_STRING_TRAVERSAL && !LooksValid()) {
return SmartArrayPointer<char>(NULL);
}
Heap* heap = GetHeap();
// Negative length means the to the end of the string.
if (length < 0) length = kMaxInt - offset;
// Compute the size of the UTF-8 string. Start at the specified offset.
Access<StringInputBuffer> buffer(
heap->isolate()->objects_string_input_buffer());
buffer->Reset(offset, this);
int character_position = offset;
int utf8_bytes = 0;
int last = unibrow::Utf16::kNoPreviousCharacter;
while (buffer->has_more() && character_position++ < offset + length) {
uint16_t character = buffer->GetNext();
utf8_bytes += unibrow::Utf8::Length(character, last);
last = character;
}
if (length_return) {
*length_return = utf8_bytes;
}
char* result = NewArray<char>(utf8_bytes + 1);
// Convert the UTF-16 string to a UTF-8 buffer. Start at the specified offset.
buffer->Rewind();
buffer->Seek(offset);
character_position = offset;
int utf8_byte_position = 0;
last = unibrow::Utf16::kNoPreviousCharacter;
while (buffer->has_more() && character_position++ < offset + length) {
uint16_t character = buffer->GetNext();
if (allow_nulls == DISALLOW_NULLS && character == 0) {
character = ' ';
}
utf8_byte_position +=
unibrow::Utf8::Encode(result + utf8_byte_position, character, last);
last = character;
}
result[utf8_byte_position] = 0;
return SmartArrayPointer<char>(result);
}
SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
RobustnessFlag robust_flag,
int* length_return) {
return ToCString(allow_nulls, robust_flag, 0, -1, length_return);
}
const uc16* String::GetTwoByteData() {
return GetTwoByteData(0);
}
const uc16* String::GetTwoByteData(unsigned start) {
ASSERT(!IsAsciiRepresentationUnderneath());
switch (StringShape(this).representation_tag()) {
case kSeqStringTag:
return SeqTwoByteString::cast(this)->SeqTwoByteStringGetData(start);
case kExternalStringTag:
return ExternalTwoByteString::cast(this)->
ExternalTwoByteStringGetData(start);
case kSlicedStringTag: {
SlicedString* slice = SlicedString::cast(this);
return slice->parent()->GetTwoByteData(start + slice->offset());
}
case kConsStringTag:
UNREACHABLE();
return NULL;
}
UNREACHABLE();
return NULL;
}
SmartArrayPointer<uc16> String::ToWideCString(RobustnessFlag robust_flag) {
if (robust_flag == ROBUST_STRING_TRAVERSAL && !LooksValid()) {
return SmartArrayPointer<uc16>();
}
Heap* heap = GetHeap();
Access<StringInputBuffer> buffer(
heap->isolate()->objects_string_input_buffer());
buffer->Reset(this);
uc16* result = NewArray<uc16>(length() + 1);
int i = 0;
while (buffer->has_more()) {
uint16_t character = buffer->GetNext();
result[i++] = character;
}
result[i] = 0;
return SmartArrayPointer<uc16>(result);
}
const uc16* SeqTwoByteString::SeqTwoByteStringGetData(unsigned start) {
return reinterpret_cast<uc16*>(
reinterpret_cast<char*>(this) - kHeapObjectTag + kHeaderSize) + start;
}
void SeqTwoByteString::SeqTwoByteStringReadBlockIntoBuffer(ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
unsigned chars_read = 0;
unsigned offset = *offset_ptr;
while (chars_read < max_chars) {
uint16_t c = *reinterpret_cast<uint16_t*>(
reinterpret_cast<char*>(this) -
kHeapObjectTag + kHeaderSize + offset * kShortSize);
if (c <= kMaxAsciiCharCode) {
// Fast case for ASCII characters. Cursor is an input output argument.
if (!unibrow::CharacterStream::EncodeAsciiCharacter(c,
rbb->util_buffer,
rbb->capacity,
rbb->cursor)) {
break;
}
} else {
if (!unibrow::CharacterStream::EncodeNonAsciiCharacter(c,
rbb->util_buffer,
rbb->capacity,
rbb->cursor)) {
break;
}
}
offset++;
chars_read++;
}
*offset_ptr = offset;
rbb->remaining += chars_read;
}
const unibrow::byte* SeqAsciiString::SeqAsciiStringReadBlock(
unsigned* remaining,
unsigned* offset_ptr,
unsigned max_chars) {
const unibrow::byte* b = reinterpret_cast<unibrow::byte*>(this) -
kHeapObjectTag + kHeaderSize + *offset_ptr * kCharSize;
*remaining = max_chars;
*offset_ptr += max_chars;
return b;
}
// This will iterate unless the block of string data spans two 'halves' of
// a ConsString, in which case it will recurse. Since the block of string
// data to be read has a maximum size this limits the maximum recursion
// depth to something sane. Since C++ does not have tail call recursion
// elimination, the iteration must be explicit. Since this is not an
// -IntoBuffer method it can delegate to one of the efficient
// *AsciiStringReadBlock routines.
const unibrow::byte* ConsString::ConsStringReadBlock(ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
ConsString* current = this;
unsigned offset = *offset_ptr;
int offset_correction = 0;
while (true) {
String* left = current->first();
unsigned left_length = (unsigned)left->length();
if (left_length > offset &&
(max_chars <= left_length - offset ||
(rbb->capacity <= left_length - offset &&
(max_chars = left_length - offset, true)))) { // comma operator!
// Left hand side only - iterate unless we have reached the bottom of
// the cons tree. The assignment on the left of the comma operator is
// in order to make use of the fact that the -IntoBuffer routines can
// produce at most 'capacity' characters. This enables us to postpone
// the point where we switch to the -IntoBuffer routines (below) in order
// to maximize the chances of delegating a big chunk of work to the
// efficient *AsciiStringReadBlock routines.
if (StringShape(left).IsCons()) {
current = ConsString::cast(left);
continue;
} else {
const unibrow::byte* answer =
String::ReadBlock(left, rbb, &offset, max_chars);
*offset_ptr = offset + offset_correction;
return answer;
}
} else if (left_length <= offset) {
// Right hand side only - iterate unless we have reached the bottom of
// the cons tree.
String* right = current->second();
offset -= left_length;
offset_correction += left_length;
if (StringShape(right).IsCons()) {
current = ConsString::cast(right);
continue;
} else {
const unibrow::byte* answer =
String::ReadBlock(right, rbb, &offset, max_chars);
*offset_ptr = offset + offset_correction;
return answer;
}
} else {
// The block to be read spans two sides of the ConsString, so we call the
// -IntoBuffer version, which will recurse. The -IntoBuffer methods
// are able to assemble data from several part strings because they use
// the util_buffer to store their data and never return direct pointers
// to their storage. We don't try to read more than the buffer capacity
// here or we can get too much recursion.
ASSERT(rbb->remaining == 0);
ASSERT(rbb->cursor == 0);
current->ConsStringReadBlockIntoBuffer(
rbb,
&offset,
max_chars > rbb->capacity ? rbb->capacity : max_chars);
*offset_ptr = offset + offset_correction;
return rbb->util_buffer;
}
}
}
const unibrow::byte* ExternalAsciiString::ExternalAsciiStringReadBlock(
unsigned* remaining,
unsigned* offset_ptr,
unsigned max_chars) {
// Cast const char* to unibrow::byte* (signedness difference).
const unibrow::byte* b =
reinterpret_cast<const unibrow::byte*>(GetChars()) + *offset_ptr;
*remaining = max_chars;
*offset_ptr += max_chars;
return b;
}
void ExternalTwoByteString::ExternalTwoByteStringReadBlockIntoBuffer(
ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
unsigned chars_read = 0;
unsigned offset = *offset_ptr;
const uint16_t* data = GetChars();
while (chars_read < max_chars) {
uint16_t c = data[offset];
if (c <= kMaxAsciiCharCode) {
// Fast case for ASCII characters. Cursor is an input output argument.
if (!unibrow::CharacterStream::EncodeAsciiCharacter(c,
rbb->util_buffer,
rbb->capacity,
rbb->cursor))
break;
} else {
if (!unibrow::CharacterStream::EncodeNonAsciiCharacter(c,
rbb->util_buffer,
rbb->capacity,
rbb->cursor))
break;
}
offset++;
chars_read++;
}
*offset_ptr = offset;
rbb->remaining += chars_read;
}
void SeqAsciiString::SeqAsciiStringReadBlockIntoBuffer(ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
unsigned capacity = rbb->capacity - rbb->cursor;
if (max_chars > capacity) max_chars = capacity;
memcpy(rbb->util_buffer + rbb->cursor,
reinterpret_cast<char*>(this) - kHeapObjectTag + kHeaderSize +
*offset_ptr * kCharSize,
max_chars);
rbb->remaining += max_chars;
*offset_ptr += max_chars;
rbb->cursor += max_chars;
}
void ExternalAsciiString::ExternalAsciiStringReadBlockIntoBuffer(
ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
unsigned capacity = rbb->capacity - rbb->cursor;
if (max_chars > capacity) max_chars = capacity;
memcpy(rbb->util_buffer + rbb->cursor, GetChars() + *offset_ptr, max_chars);
rbb->remaining += max_chars;
*offset_ptr += max_chars;
rbb->cursor += max_chars;
}
// This method determines the type of string involved and then copies
// a whole chunk of characters into a buffer, or returns a pointer to a buffer
// where they can be found. The pointer is not necessarily valid across a GC
// (see AsciiStringReadBlock).
const unibrow::byte* String::ReadBlock(String* input,
ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
ASSERT(*offset_ptr <= static_cast<unsigned>(input->length()));
if (max_chars == 0) {
rbb->remaining = 0;
return NULL;
}
switch (StringShape(input).representation_tag()) {
case kSeqStringTag:
if (input->IsAsciiRepresentation()) {
SeqAsciiString* str = SeqAsciiString::cast(input);
return str->SeqAsciiStringReadBlock(&rbb->remaining,
offset_ptr,
max_chars);
} else {
SeqTwoByteString* str = SeqTwoByteString::cast(input);
str->SeqTwoByteStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return rbb->util_buffer;
}
case kConsStringTag:
return ConsString::cast(input)->ConsStringReadBlock(rbb,
offset_ptr,
max_chars);
case kExternalStringTag:
if (input->IsAsciiRepresentation()) {
return ExternalAsciiString::cast(input)->ExternalAsciiStringReadBlock(
&rbb->remaining,
offset_ptr,
max_chars);
} else {
ExternalTwoByteString::cast(input)->
ExternalTwoByteStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return rbb->util_buffer;
}
case kSlicedStringTag:
return SlicedString::cast(input)->SlicedStringReadBlock(rbb,
offset_ptr,
max_chars);
default:
break;
}
UNREACHABLE();
return 0;
}
void Relocatable::PostGarbageCollectionProcessing() {
Isolate* isolate = Isolate::Current();
Relocatable* current = isolate->relocatable_top();
while (current != NULL) {
current->PostGarbageCollection();
current = current->prev_;
}
}
// Reserve space for statics needing saving and restoring.
int Relocatable::ArchiveSpacePerThread() {
return sizeof(Isolate::Current()->relocatable_top());
}
// Archive statics that are thread local.
char* Relocatable::ArchiveState(Isolate* isolate, char* to) {
*reinterpret_cast<Relocatable**>(to) = isolate->relocatable_top();
isolate->set_relocatable_top(NULL);
return to + ArchiveSpacePerThread();
}
// Restore statics that are thread local.
char* Relocatable::RestoreState(Isolate* isolate, char* from) {
isolate->set_relocatable_top(*reinterpret_cast<Relocatable**>(from));
return from + ArchiveSpacePerThread();
}
char* Relocatable::Iterate(ObjectVisitor* v, char* thread_storage) {
Relocatable* top = *reinterpret_cast<Relocatable**>(thread_storage);
Iterate(v, top);
return thread_storage + ArchiveSpacePerThread();
}
void Relocatable::Iterate(ObjectVisitor* v) {
Isolate* isolate = Isolate::Current();
Iterate(v, isolate->relocatable_top());
}
void Relocatable::Iterate(ObjectVisitor* v, Relocatable* top) {
Relocatable* current = top;
while (current != NULL) {
current->IterateInstance(v);
current = current->prev_;
}
}
FlatStringReader::FlatStringReader(Isolate* isolate, Handle<String> str)
: Relocatable(isolate),
str_(str.location()),
length_(str->length()) {
PostGarbageCollection();
}
FlatStringReader::FlatStringReader(Isolate* isolate, Vector<const char> input)
: Relocatable(isolate),
str_(0),
is_ascii_(true),
length_(input.length()),
start_(input.start()) { }
void FlatStringReader::PostGarbageCollection() {
if (str_ == NULL) return;
Handle<String> str(str_);
ASSERT(str->IsFlat());
String::FlatContent content = str->GetFlatContent();
ASSERT(content.IsFlat());
is_ascii_ = content.IsAscii();
if (is_ascii_) {
start_ = content.ToAsciiVector().start();
} else {
start_ = content.ToUC16Vector().start();
}
}
void StringInputBuffer::Seek(unsigned pos) {
Reset(pos, input_);
}
void SafeStringInputBuffer::Seek(unsigned pos) {
Reset(pos, input_);
}
// This method determines the type of string involved and then copies
// a whole chunk of characters into a buffer. It can be used with strings
// that have been glued together to form a ConsString and which must cooperate
// to fill up a buffer.
void String::ReadBlockIntoBuffer(String* input,
ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
ASSERT(*offset_ptr <= (unsigned)input->length());
if (max_chars == 0) return;
switch (StringShape(input).representation_tag()) {
case kSeqStringTag:
if (input->IsAsciiRepresentation()) {
SeqAsciiString::cast(input)->SeqAsciiStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return;
} else {
SeqTwoByteString::cast(input)->SeqTwoByteStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return;
}
case kConsStringTag:
ConsString::cast(input)->ConsStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return;
case kExternalStringTag:
if (input->IsAsciiRepresentation()) {
ExternalAsciiString::cast(input)->
ExternalAsciiStringReadBlockIntoBuffer(rbb, offset_ptr, max_chars);
} else {
ExternalTwoByteString::cast(input)->
ExternalTwoByteStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
}
return;
case kSlicedStringTag:
SlicedString::cast(input)->SlicedStringReadBlockIntoBuffer(rbb,
offset_ptr,
max_chars);
return;
default:
break;
}
UNREACHABLE();
return;
}
const unibrow::byte* String::ReadBlock(String* input,
unibrow::byte* util_buffer,
unsigned capacity,
unsigned* remaining,
unsigned* offset_ptr) {
ASSERT(*offset_ptr <= (unsigned)input->length());
unsigned chars = input->length() - *offset_ptr;
ReadBlockBuffer rbb(util_buffer, 0, capacity, 0);
const unibrow::byte* answer = ReadBlock(input, &rbb, offset_ptr, chars);
ASSERT(rbb.remaining <= static_cast<unsigned>(input->length()));
*remaining = rbb.remaining;
return answer;
}
const unibrow::byte* String::ReadBlock(String** raw_input,
unibrow::byte* util_buffer,
unsigned capacity,
unsigned* remaining,
unsigned* offset_ptr) {
Handle<String> input(raw_input);
ASSERT(*offset_ptr <= (unsigned)input->length());
unsigned chars = input->length() - *offset_ptr;
if (chars > capacity) chars = capacity;
ReadBlockBuffer rbb(util_buffer, 0, capacity, 0);
ReadBlockIntoBuffer(*input, &rbb, offset_ptr, chars);
ASSERT(rbb.remaining <= static_cast<unsigned>(input->length()));
*remaining = rbb.remaining;
return rbb.util_buffer;
}
// This will iterate unless the block of string data spans two 'halves' of
// a ConsString, in which case it will recurse. Since the block of string
// data to be read has a maximum size this limits the maximum recursion
// depth to something sane. Since C++ does not have tail call recursion
// elimination, the iteration must be explicit.
void ConsString::ConsStringReadBlockIntoBuffer(ReadBlockBuffer* rbb,
unsigned* offset_ptr,
unsigned max_chars) {
ConsString* current = this;
unsigned offset = *offset_ptr;
int offset_correction = 0;
while (true) {
String* left = current->first();
unsigned left_length = (unsigned)left->length();
if (left_length > offset &&
max_chars <= left_length - offset) {
// Left hand side only - iterate unless we have reached the bottom of
// the cons tree.
if (StringShape(left).IsCons()) {
current = ConsString::cast(left);
continue;
} else {
String::ReadBlockIntoBuffer(left, rbb, &offset, max_chars);
*offset_ptr = offset + offset_correction;
return;
}
} else if (left_length <= offset) {
// Right hand side only - iterate unless we have reached the bottom of
// the cons tree.
offset -= left_length;
offset_correction += left_length;
String* right = current->second();
if (StringShape(right).IsCons()) {
current = ConsString::cast(right);
continue;
} else {
String::ReadBlockIntoBuffer(right, rbb, &offset, max_chars);
*offset_ptr = offset + offset_correction;
return;
}
} else {
// The block to be read spans two sides of the ConsString, so we recurse.
// First recurse on the left.
max_chars -= left_length - offset;
String::ReadBlockIntoBuffer(left, rbb, &offset, left_length - offset);
// We may have reached the max or there may not have been enough space
// in the buffer for the characters in the left hand side.
if (offset == left_length) {
// Recurse on the right.
String* right = String::cast(current->second());
offset -= left_length;
offset_correction += left_length;
String::ReadBlockIntoBuffer(right, rbb, &offset, max_chars);
}
*offset_ptr = offset + offset_correction;
return;
}
}
}
uint16_t ConsString::ConsStringGet(int index) {
ASSERT(index >= 0 && index < this->length());
// Check for a flattened cons string
if (second()->length() == 0) {
String* left = first();
return left->Get(index);
}
String* string = String::cast(this);
while (true) {
if (StringShape(string).IsCons()) {
ConsString* cons_string = ConsString::cast(string);
String* left = cons_string->first();
if (left->length() > index) {
string = left;
} else {
index -= left->length();
string = cons_string->second();
}
} else {
return string->Get(index);
}
}
UNREACHABLE();
return 0;
}
uint16_t SlicedString::SlicedStringGet(int index) {
return parent()->Get(offset() + index);
}
const unibrow::byte* SlicedString::SlicedStringReadBlock(
ReadBlockBuffer* buffer, unsigned* offset_ptr, unsigned chars) {
unsigned offset = this->offset();
*offset_ptr += offset;
const unibrow::byte* answer = String::ReadBlock(String::cast(parent()),
buffer, offset_ptr, chars);
*offset_ptr -= offset;
return answer;
}
void SlicedString::SlicedStringReadBlockIntoBuffer(
ReadBlockBuffer* buffer, unsigned* offset_ptr, unsigned chars) {
unsigned offset = this->offset();
*offset_ptr += offset;
String::ReadBlockIntoBuffer(String::cast(parent()),
buffer, offset_ptr, chars);
*offset_ptr -= offset;
}
template <typename sinkchar>
void String::WriteToFlat(String* src,
sinkchar* sink,
int f,
int t) {
String* source = src;
int from = f;
int to = t;
while (true) {
ASSERT(0 <= from && from <= to && to <= source->length());
switch (StringShape(source).full_representation_tag()) {
case kAsciiStringTag | kExternalStringTag: {
CopyChars(sink,
ExternalAsciiString::cast(source)->GetChars() + from,
to - from);
return;
}
case kTwoByteStringTag | kExternalStringTag: {
const uc16* data =
ExternalTwoByteString::cast(source)->GetChars();
CopyChars(sink,
data + from,
to - from);
return;
}
case kAsciiStringTag | kSeqStringTag: {
CopyChars(sink,
SeqAsciiString::cast(source)->GetChars() + from,
to - from);
return;
}
case kTwoByteStringTag | kSeqStringTag: {
CopyChars(sink,
SeqTwoByteString::cast(source)->GetChars() + from,
to - from);
return;
}
case kAsciiStringTag | kConsStringTag:
case kTwoByteStringTag | kConsStringTag: {
ConsString* cons_string = ConsString::cast(source);
String* first = cons_string->first();
int boundary = first->length();
if (to - boundary >= boundary - from) {
// Right hand side is longer. Recurse over left.
if (from < boundary) {
WriteToFlat(first, sink, from, boundary);
sink += boundary - from;
from = 0;
} else {
from -= boundary;
}
to -= boundary;
source = cons_string->second();
} else {
// Left hand side is longer. Recurse over right.
if (to > boundary) {
String* second = cons_string->second();
// When repeatedly appending to a string, we get a cons string that
// is unbalanced to the left, a list, essentially. We inline the
// common case of sequential ascii right child.
if (to - boundary == 1) {
sink[boundary - from] = static_cast<sinkchar>(second->Get(0));
} else if (second->IsSeqAsciiString()) {
CopyChars(sink + boundary - from,
SeqAsciiString::cast(second)->GetChars(),
to - boundary);
} else {
WriteToFlat(second,
sink + boundary - from,
0,
to - boundary);
}
to = boundary;
}
source = first;
}
break;
}
case kAsciiStringTag | kSlicedStringTag:
case kTwoByteStringTag | kSlicedStringTag: {
SlicedString* slice = SlicedString::cast(source);
unsigned offset = slice->offset();
WriteToFlat(slice->parent(), sink, from + offset, to + offset);
return;
}
}
}
}
template <typename IteratorA, typename IteratorB>
static inline bool CompareStringContents(IteratorA* ia, IteratorB* ib) {
// General slow case check. We know that the ia and ib iterators
// have the same length.
while (ia->has_more()) {
uint32_t ca = ia->GetNext();
uint32_t cb = ib->GetNext();
ASSERT(ca <= unibrow::Utf16::kMaxNonSurrogateCharCode);
ASSERT(cb <= unibrow::Utf16::kMaxNonSurrogateCharCode);
if (ca != cb)
return false;
}
return true;
}
// Compares the contents of two strings by reading and comparing
// int-sized blocks of characters.
template <typename Char>
static inline bool CompareRawStringContents(Vector<Char> a, Vector<Char> b) {
int length = a.length();
ASSERT_EQ(length, b.length());
const Char* pa = a.start();
const Char* pb = b.start();
int i = 0;
#ifndef V8_HOST_CAN_READ_UNALIGNED
// If this architecture isn't comfortable reading unaligned ints
// then we have to check that the strings are aligned before
// comparing them blockwise.
const int kAlignmentMask = sizeof(uint32_t) - 1; // NOLINT
uint32_t pa_addr = reinterpret_cast<uint32_t>(pa);
uint32_t pb_addr = reinterpret_cast<uint32_t>(pb);
if (((pa_addr & kAlignmentMask) | (pb_addr & kAlignmentMask)) == 0) {
#endif
const int kStepSize = sizeof(int) / sizeof(Char); // NOLINT
int endpoint = length - kStepSize;
// Compare blocks until we reach near the end of the string.
for (; i <= endpoint; i += kStepSize) {
uint32_t wa = *reinterpret_cast<const uint32_t*>(pa + i);
uint32_t wb = *reinterpret_cast<const uint32_t*>(pb + i);
if (wa != wb) {
return false;
}
}
#ifndef V8_HOST_CAN_READ_UNALIGNED
}
#endif
// Compare the remaining characters that didn't fit into a block.
for (; i < length; i++) {
if (a[i] != b[i]) {
return false;
}
}
return true;
}
template <typename IteratorA>
static inline bool CompareStringContentsPartial(Isolate* isolate,
IteratorA* ia,
String* b) {
String::FlatContent content = b->GetFlatContent();
if (content.IsFlat()) {
if (content.IsAscii()) {
VectorIterator<char> ib(content.ToAsciiVector());
return CompareStringContents(ia, &ib);
} else {
VectorIterator<uc16> ib(content.ToUC16Vector());
return CompareStringContents(ia, &ib);
}
} else {
isolate->objects_string_compare_buffer_b()->Reset(0, b);
return CompareStringContents(ia,
isolate->objects_string_compare_buffer_b());
}
}
bool String::SlowEquals(String* other) {
// Fast check: negative check with lengths.
int len = length();
if (len != other->length()) return false;
if (len == 0) return true;
// Fast check: if hash code is computed for both strings
// a fast negative check can be performed.
if (HasHashCode() && other->HasHashCode()) {
#ifdef DEBUG
if (FLAG_enable_slow_asserts) {
if (Hash() != other->Hash()) {
bool found_difference = false;
for (int i = 0; i < len; i++) {
if (Get(i) != other->Get(i)) {
found_difference = true;
break;
}
}
ASSERT(found_difference);
}
}
#endif
if (Hash() != other->Hash()) return false;
}
// We know the strings are both non-empty. Compare the first chars
// before we try to flatten the strings.
if (this->Get(0) != other->Get(0)) return false;
String* lhs = this->TryFlattenGetString();
String* rhs = other->TryFlattenGetString();
if (StringShape(lhs).IsSequentialAscii() &&
StringShape(rhs).IsSequentialAscii()) {
const char* str1 = SeqAsciiString::cast(lhs)->GetChars();
const char* str2 = SeqAsciiString::cast(rhs)->GetChars();
return CompareRawStringContents(Vector<const char>(str1, len),
Vector<const char>(str2, len));
}
Isolate* isolate = GetIsolate();
String::FlatContent lhs_content = lhs->GetFlatContent();
String::FlatContent rhs_content = rhs->GetFlatContent();
if (lhs_content.IsFlat()) {
if (lhs_content.IsAscii()) {
Vector<const char> vec1 = lhs_content.ToAsciiVector();
if (rhs_content.IsFlat()) {
if (rhs_content.IsAscii()) {
Vector<const char> vec2 = rhs_content.ToAsciiVector();
return CompareRawStringContents(vec1, vec2);
} else {
VectorIterator<char> buf1(vec1);
VectorIterator<uc16> ib(rhs_content.ToUC16Vector());
return CompareStringContents(&buf1, &ib);
}
} else {
VectorIterator<char> buf1(vec1);
isolate->objects_string_compare_buffer_b()->Reset(0, rhs);
return CompareStringContents(&buf1,
isolate->objects_string_compare_buffer_b());
}
} else {
Vector<const uc16> vec1 = lhs_content.ToUC16Vector();
if (rhs_content.IsFlat()) {
if (rhs_content.IsAscii()) {
VectorIterator<uc16> buf1(vec1);
VectorIterator<char> ib(rhs_content.ToAsciiVector());
return CompareStringContents(&buf1, &ib);
} else {
Vector<const uc16> vec2(rhs_content.ToUC16Vector());
return CompareRawStringContents(vec1, vec2);
}
} else {
VectorIterator<uc16> buf1(vec1);
isolate->objects_string_compare_buffer_b()->Reset(0, rhs);
return CompareStringContents(&buf1,
isolate->objects_string_compare_buffer_b());
}
}
} else {
isolate->objects_string_compare_buffer_a()->Reset(0, lhs);
return CompareStringContentsPartial(isolate,
isolate->objects_string_compare_buffer_a(), rhs);
}
}
bool String::MarkAsUndetectable() {
if (StringShape(this).IsSymbol()) return false;
Map* map = this->map();
Heap* heap = GetHeap();
if (map == heap->string_map()) {
this->set_map(heap->undetectable_string_map());
return true;
} else if (map == heap->ascii_string_map()) {
this->set_map(heap->undetectable_ascii_string_map());
return true;
}
// Rest cannot be marked as undetectable
return false;
}
bool String::IsEqualTo(Vector<const char> str) {
Isolate* isolate = GetIsolate();
int slen = length();
Access<UnicodeCache::Utf8Decoder>
decoder(isolate->unicode_cache()->utf8_decoder());
decoder->Reset(str.start(), str.length());
int i;
for (i = 0; i < slen && decoder->has_more(); i++) {
uint32_t r = decoder->GetNext();
if (r > unibrow::Utf16::kMaxNonSurrogateCharCode) {
if (i > slen - 1) return false;
if (Get(i++) != unibrow::Utf16::LeadSurrogate(r)) return false;
if (Get(i) != unibrow::Utf16::TrailSurrogate(r)) return false;
} else {
if (Get(i) != r) return false;
}
}
return i == slen && !decoder->has_more();
}
bool String::IsAsciiEqualTo(Vector<const char> str) {
int slen = length();
if (str.length() != slen) return false;
FlatContent content = GetFlatContent();
if (content.IsAscii()) {
return CompareChars(content.ToAsciiVector().start(),
str.start(), slen) == 0;
}
for (int i = 0; i < slen; i++) {
if (Get(i) != static_cast<uint16_t>(str[i])) return false;
}
return true;
}
bool String::IsTwoByteEqualTo(Vector<const uc16> str) {
int slen = length();
if (str.length() != slen) return false;
FlatContent content = GetFlatContent();
if (content.IsTwoByte()) {
return CompareChars(content.ToUC16Vector().start(), str.start(), slen) == 0;
}
for (int i = 0; i < slen; i++) {
if (Get(i) != str[i]) return false;
}
return true;
}
uint32_t String::ComputeAndSetHash() {
// Should only be called if hash code has not yet been computed.
ASSERT(!HasHashCode());
const int len = length();
// Compute the hash code.
uint32_t field = 0;
if (StringShape(this).IsSequentialAscii()) {
field = HashSequentialString(SeqAsciiString::cast(this)->GetChars(),
len,
GetHeap()->HashSeed());
} else if (StringShape(this).IsSequentialTwoByte()) {
field = HashSequentialString(SeqTwoByteString::cast(this)->GetChars(),
len,
GetHeap()->HashSeed());
} else {
StringInputBuffer buffer(this);
field = ComputeHashField(&buffer, len, GetHeap()->HashSeed());
}
// Store the hash code in the object.
set_hash_field(field);
// Check the hash code is there.
ASSERT(HasHashCode());
uint32_t result = field >> kHashShift;
ASSERT(result != 0); // Ensure that the hash value of 0 is never computed.
return result;
}
bool String::ComputeArrayIndex(unibrow::CharacterStream* buffer,
uint32_t* index,
int length) {
if (length == 0 || length > kMaxArrayIndexSize) return false;
uc32 ch = buffer->GetNext();
// If the string begins with a '0' character, it must only consist
// of it to be a legal array index.
if (ch == '0') {
*index = 0;
return length == 1;
}
// Convert string to uint32 array index; character by character.
int d = ch - '0';
if (d < 0 || d > 9) return false;
uint32_t result = d;
while (buffer->has_more()) {
d = buffer->GetNext() - '0';
if (d < 0 || d > 9) return false;
// Check that the new result is below the 32 bit limit.
if (result > 429496729U - ((d > 5) ? 1 : 0)) return false;
result = (result * 10) + d;
}
*index = result;
return true;
}
bool String::SlowAsArrayIndex(uint32_t* index) {
if (length() <= kMaxCachedArrayIndexLength) {
Hash(); // force computation of hash code
uint32_t field = hash_field();
if ((field & kIsNotArrayIndexMask) != 0) return false;
// Isolate the array index form the full hash field.
*index = (kArrayIndexHashMask & field) >> kHashShift;
return true;
} else {
StringInputBuffer buffer(this);
return ComputeArrayIndex(&buffer, index, length());
}
}
uint32_t StringHasher::MakeArrayIndexHash(uint32_t value, int length) {
// For array indexes mix the length into the hash as an array index could
// be zero.
ASSERT(length > 0);
ASSERT(length <= String::kMaxArrayIndexSize);
ASSERT(TenToThe(String::kMaxCachedArrayIndexLength) <
(1 << String::kArrayIndexValueBits));
value <<= String::kHashShift;
value |= length << String::kArrayIndexHashLengthShift;
ASSERT((value & String::kIsNotArrayIndexMask) == 0);
ASSERT((length > String::kMaxCachedArrayIndexLength) ||
(value & String::kContainsCachedArrayIndexMask) == 0);
return value;
}
void StringHasher::AddSurrogatePair(uc32 c) {
uint16_t lead = unibrow::Utf16::LeadSurrogate(c);
AddCharacter(lead);
uint16_t trail = unibrow::Utf16::TrailSurrogate(c);
AddCharacter(trail);
}
void StringHasher::AddSurrogatePairNoIndex(uc32 c) {
uint16_t lead = unibrow::Utf16::LeadSurrogate(c);
AddCharacterNoIndex(lead);
uint16_t trail = unibrow::Utf16::TrailSurrogate(c);
AddCharacterNoIndex(trail);
}
uint32_t StringHasher::GetHashField() {
ASSERT(is_valid());
if (length_ <= String::kMaxHashCalcLength) {
if (is_array_index()) {
return MakeArrayIndexHash(array_index(), length_);
}
return (GetHash() << String::kHashShift) | String::kIsNotArrayIndexMask;
} else {
return (length_ << String::kHashShift) | String::kIsNotArrayIndexMask;
}
}
uint32_t String::ComputeHashField(unibrow::CharacterStream* buffer,
int length,
uint32_t seed) {
StringHasher hasher(length, seed);
// Very long strings have a trivial hash that doesn't inspect the
// string contents.
if (hasher.has_trivial_hash()) {
return hasher.GetHashField();
}
// Do the iterative array index computation as long as there is a
// chance this is an array index.
while (buffer->has_more() && hasher.is_array_index()) {
hasher.AddCharacter(buffer->GetNext());
}
// Process the remaining characters without updating the array
// index.
while (buffer->has_more()) {
hasher.AddCharacterNoIndex(buffer->GetNext());
}
return hasher.GetHashField();
}
MaybeObject* String::SubString(int start, int end, PretenureFlag pretenure) {
Heap* heap = GetHeap();
if (start == 0 && end == length()) return this;
MaybeObject* result = heap->AllocateSubString(this, start, end, pretenure);
return result;
}
void String::PrintOn(FILE* file) {
int length = this->length();
for (int i = 0; i < length; i++) {
fprintf(file, "%c", Get(i));
}
}
void Map::CreateOneBackPointer(Object* transition_target) {
if (!transition_target->IsMap()) return;
Map* target = Map::cast(transition_target);
#ifdef DEBUG
// Verify target.
Object* source_prototype = prototype();
Object* target_prototype = target->prototype();
ASSERT(source_prototype->IsJSReceiver() ||
source_prototype->IsMap() ||
source_prototype->IsNull());
ASSERT(target_prototype->IsJSReceiver() ||
target_prototype->IsNull());
ASSERT(source_prototype->IsMap() ||
source_prototype == target_prototype);
#endif
// Point target back to source. set_prototype() will not let us set
// the prototype to a map, as we do here.
*RawField(target, kPrototypeOffset) = this;
}
void Map::CreateBackPointers() {
DescriptorArray* descriptors = instance_descriptors();
for (int i = 0; i < descriptors->number_of_descriptors(); i++) {
switch (descriptors->GetType(i)) {
case MAP_TRANSITION:
case CONSTANT_TRANSITION:
CreateOneBackPointer(descriptors->GetValue(i));
break;
case ELEMENTS_TRANSITION: {
Object* object = descriptors->GetValue(i);
if (object->IsMap()) {
CreateOneBackPointer(object);
} else {
FixedArray* array = FixedArray::cast(object);
for (int i = 0; i < array->length(); ++i) {
CreateOneBackPointer(array->get(i));
}
}
break;
}
case CALLBACKS: {
Object* object = descriptors->GetValue(i);
if (object->IsAccessorPair()) {
AccessorPair* accessors = AccessorPair::cast(object);
CreateOneBackPointer(accessors->getter());
CreateOneBackPointer(accessors->setter());
}
break;
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION:
case HANDLER:
case INTERCEPTOR:
case NULL_DESCRIPTOR:
break;
}
}
}
bool Map::RestoreOneBackPointer(Object* object,
Object* real_prototype,
bool* keep_entry) {
if (!object->IsMap()) return false;
Map* map = Map::cast(object);
if (Marking::MarkBitFrom(map).Get()) {
*keep_entry = true;
return false;
}
ASSERT(map->prototype() == this || map->prototype() == real_prototype);
// Getter prototype() is read-only, set_prototype() has side effects.
*RawField(map, Map::kPrototypeOffset) = real_prototype;
return true;
}
void Map::ClearNonLiveTransitions(Heap* heap, Object* real_prototype) {
DescriptorArray* d = DescriptorArray::cast(
*RawField(this, Map::kInstanceDescriptorsOrBitField3Offset));
if (d->IsEmpty()) return;
Smi* NullDescriptorDetails =
PropertyDetails(NONE, NULL_DESCRIPTOR).AsSmi();
FixedArray* contents = FixedArray::cast(
d->get(DescriptorArray::kContentArrayIndex));
ASSERT(contents->length() >= 2);
for (int i = 0; i < contents->length(); i += 2) {
// If the pair (value, details) is a map transition, check if the target is
// live. If not, null the descriptor. Also drop the back pointer for that
// map transition, so that this map is not reached again by following a back
// pointer from a non-live object.
bool keep_entry = false;
PropertyDetails details(Smi::cast(contents->get(i + 1)));
switch (details.type()) {
case MAP_TRANSITION:
case CONSTANT_TRANSITION:
RestoreOneBackPointer(contents->get(i), real_prototype, &keep_entry);
break;
case ELEMENTS_TRANSITION: {
Object* object = contents->get(i);
if (object->IsMap()) {
RestoreOneBackPointer(object, real_prototype, &keep_entry);
} else {
FixedArray* array = FixedArray::cast(object);
for (int j = 0; j < array->length(); ++j) {
if (RestoreOneBackPointer(array->get(j),
real_prototype,
&keep_entry)) {
array->set_undefined(j);
}
}
}
break;
}
case CALLBACKS: {
Object* object = contents->get(i);
if (object->IsAccessorPair()) {
AccessorPair* accessors = AccessorPair::cast(object);
if (RestoreOneBackPointer(accessors->getter(),
real_prototype,
&keep_entry)) {
accessors->set_getter(heap->the_hole_value());
}
if (RestoreOneBackPointer(accessors->setter(),
real_prototype,
&keep_entry)) {
accessors->set_setter(heap->the_hole_value());
}
} else {
keep_entry = true;
}
break;
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION:
case HANDLER:
case INTERCEPTOR:
case NULL_DESCRIPTOR:
keep_entry = true;
break;
}
// Make sure that an entry containing only dead transitions gets collected.
// What we *really* want to do here is removing this entry completely, but
// for technical reasons we can't do this, so we zero it out instead.
if (!keep_entry) {
contents->set_unchecked(i + 1, NullDescriptorDetails);
contents->set_null_unchecked(heap, i);
}
}
}
int Map::Hash() {
// For performance reasons we only hash the 3 most variable fields of a map:
// constructor, prototype and bit_field2.
// Shift away the tag.
int hash = (static_cast<uint32_t>(
reinterpret_cast<uintptr_t>(constructor())) >> 2);
// XOR-ing the prototype and constructor directly yields too many zero bits
// when the two pointers are close (which is fairly common).
// To avoid this we shift the prototype 4 bits relatively to the constructor.
hash ^= (static_cast<uint32_t>(
reinterpret_cast<uintptr_t>(prototype())) << 2);
return hash ^ (hash >> 16) ^ bit_field2();
}
bool Map::EquivalentToForNormalization(Map* other,
PropertyNormalizationMode mode) {
return
constructor() == other->constructor() &&
prototype() == other->prototype() &&
inobject_properties() == ((mode == CLEAR_INOBJECT_PROPERTIES) ?
0 :
other->inobject_properties()) &&
instance_type() == other->instance_type() &&
bit_field() == other->bit_field() &&
bit_field2() == other->bit_field2() &&
(bit_field3() & ~(1<<Map::kIsShared)) ==
(other->bit_field3() & ~(1<<Map::kIsShared));
}
void JSFunction::JSFunctionIterateBody(int object_size, ObjectVisitor* v) {
// Iterate over all fields in the body but take care in dealing with
// the code entry.
IteratePointers(v, kPropertiesOffset, kCodeEntryOffset);
v->VisitCodeEntry(this->address() + kCodeEntryOffset);
IteratePointers(v, kCodeEntryOffset + kPointerSize, object_size);
}
void JSFunction::MarkForLazyRecompilation() {
ASSERT(is_compiled() && !IsOptimized());
ASSERT(shared()->allows_lazy_compilation() ||
code()->optimizable());
Builtins* builtins = GetIsolate()->builtins();
ReplaceCode(builtins->builtin(Builtins::kLazyRecompile));
}
bool SharedFunctionInfo::EnsureCompiled(Handle<SharedFunctionInfo> shared,
ClearExceptionFlag flag) {
return shared->is_compiled() || CompileLazy(shared, flag);
}
static bool CompileLazyHelper(CompilationInfo* info,
ClearExceptionFlag flag) {
// Compile the source information to a code object.
ASSERT(info->IsOptimizing() || !info->shared_info()->is_compiled());
ASSERT(!info->isolate()->has_pending_exception());
bool result = Compiler::CompileLazy(info);
ASSERT(result != Isolate::Current()->has_pending_exception());
if (!result && flag == CLEAR_EXCEPTION) {
info->isolate()->clear_pending_exception();
}
return result;
}
bool SharedFunctionInfo::CompileLazy(Handle<SharedFunctionInfo> shared,
ClearExceptionFlag flag) {
CompilationInfo info(shared);
return CompileLazyHelper(&info, flag);
}
bool JSFunction::CompileLazy(Handle<JSFunction> function,
ClearExceptionFlag flag) {
bool result = true;
if (function->shared()->is_compiled()) {
function->ReplaceCode(function->shared()->code());
function->shared()->set_code_age(0);
} else {
CompilationInfo info(function);
result = CompileLazyHelper(&info, flag);
ASSERT(!result || function->is_compiled());
}
return result;
}
bool JSFunction::CompileOptimized(Handle<JSFunction> function,
int osr_ast_id,
ClearExceptionFlag flag) {
CompilationInfo info(function);
info.SetOptimizing(osr_ast_id);
return CompileLazyHelper(&info, flag);
}
bool JSFunction::IsInlineable() {
if (IsBuiltin()) return false;
SharedFunctionInfo* shared_info = shared();
// Check that the function has a script associated with it.
if (!shared_info->script()->IsScript()) return false;
if (shared_info->optimization_disabled()) return false;
Code* code = shared_info->code();
if (code->kind() == Code::OPTIMIZED_FUNCTION) return true;
// If we never ran this (unlikely) then lets try to optimize it.
if (code->kind() != Code::FUNCTION) return true;
return code->optimizable();
}
MaybeObject* JSFunction::SetInstancePrototype(Object* value) {
ASSERT(value->IsJSReceiver());
Heap* heap = GetHeap();
if (has_initial_map()) {
// If the function has allocated the initial map
// replace it with a copy containing the new prototype.
Map* new_map;
MaybeObject* maybe_new_map = initial_map()->CopyDropTransitions();
if (!maybe_new_map->To(&new_map)) return maybe_new_map;
new_map->set_prototype(value);
MaybeObject* maybe_object =
set_initial_map_and_cache_transitions(new_map);
if (maybe_object->IsFailure()) return maybe_object;
} else {
// Put the value in the initial map field until an initial map is
// needed. At that point, a new initial map is created and the
// prototype is put into the initial map where it belongs.
set_prototype_or_initial_map(value);
}
heap->ClearInstanceofCache();
return value;
}
MaybeObject* JSFunction::SetPrototype(Object* value) {
ASSERT(should_have_prototype());
Object* construct_prototype = value;
// If the value is not a JSReceiver, store the value in the map's
// constructor field so it can be accessed. Also, set the prototype
// used for constructing objects to the original object prototype.
// See ECMA-262 13.2.2.
if (!value->IsJSReceiver()) {
// Copy the map so this does not affect unrelated functions.
// Remove map transitions because they point to maps with a
// different prototype.
Map* new_map;
{ MaybeObject* maybe_new_map = map()->CopyDropTransitions();
if (!maybe_new_map->To(&new_map)) return maybe_new_map;
}
Heap* heap = new_map->GetHeap();
set_map(new_map);
new_map->set_constructor(value);
new_map->set_non_instance_prototype(true);
construct_prototype =
heap->isolate()->context()->global_context()->
initial_object_prototype();
} else {
map()->set_non_instance_prototype(false);
}
return SetInstancePrototype(construct_prototype);
}
Object* JSFunction::RemovePrototype() {
Context* global_context = context()->global_context();
Map* no_prototype_map = shared()->is_classic_mode()
? global_context->function_without_prototype_map()
: global_context->strict_mode_function_without_prototype_map();
if (map() == no_prototype_map) {
// Be idempotent.
return this;
}
ASSERT(map() == (shared()->is_classic_mode()
? global_context->function_map()
: global_context->strict_mode_function_map()));
set_map(no_prototype_map);
set_prototype_or_initial_map(no_prototype_map->GetHeap()->the_hole_value());
return this;
}
Object* JSFunction::SetInstanceClassName(String* name) {
shared()->set_instance_class_name(name);
return this;
}
void JSFunction::PrintName(FILE* out) {
SmartArrayPointer<char> name = shared()->DebugName()->ToCString();
PrintF(out, "%s", *name);
}
Context* JSFunction::GlobalContextFromLiterals(FixedArray* literals) {
return Context::cast(literals->get(JSFunction::kLiteralGlobalContextIndex));
}
MaybeObject* Oddball::Initialize(const char* to_string,
Object* to_number,
byte kind) {
String* symbol;
{ MaybeObject* maybe_symbol =
Isolate::Current()->heap()->LookupAsciiSymbol(to_string);
if (!maybe_symbol->To(&symbol)) return maybe_symbol;
}
set_to_string(symbol);
set_to_number(to_number);
set_kind(kind);
return this;
}
String* SharedFunctionInfo::DebugName() {
Object* n = name();
if (!n->IsString() || String::cast(n)->length() == 0) return inferred_name();
return String::cast(n);
}
bool SharedFunctionInfo::HasSourceCode() {
return !script()->IsUndefined() &&
!reinterpret_cast<Script*>(script())->source()->IsUndefined();
}
Handle<Object> SharedFunctionInfo::GetSourceCode() {
if (!HasSourceCode()) return GetIsolate()->factory()->undefined_value();
Handle<String> source(String::cast(Script::cast(script())->source()));
return SubString(source, start_position(), end_position());
}
int SharedFunctionInfo::SourceSize() {
return end_position() - start_position();
}
int SharedFunctionInfo::CalculateInstanceSize() {
int instance_size =
JSObject::kHeaderSize +
expected_nof_properties() * kPointerSize;
if (instance_size > JSObject::kMaxInstanceSize) {
instance_size = JSObject::kMaxInstanceSize;
}
return instance_size;
}
int SharedFunctionInfo::CalculateInObjectProperties() {
return (CalculateInstanceSize() - JSObject::kHeaderSize) / kPointerSize;
}
bool SharedFunctionInfo::CanGenerateInlineConstructor(Object* prototype) {
// Check the basic conditions for generating inline constructor code.
if (!FLAG_inline_new
|| !has_only_simple_this_property_assignments()
|| this_property_assignments_count() == 0) {
return false;
}
// If the prototype is null inline constructors cause no problems.
if (!prototype->IsJSObject()) {
ASSERT(prototype->IsNull());
return true;
}
Heap* heap = GetHeap();
// Traverse the proposed prototype chain looking for setters for properties of
// the same names as are set by the inline constructor.
for (Object* obj = prototype;
obj != heap->null_value();
obj = obj->GetPrototype()) {
JSObject* js_object = JSObject::cast(obj);
for (int i = 0; i < this_property_assignments_count(); i++) {
LookupResult result(heap->isolate());
String* name = GetThisPropertyAssignmentName(i);
js_object->LocalLookupRealNamedProperty(name, &result);
if (result.IsFound() && result.type() == CALLBACKS) {
return false;
}
}
}
return true;
}
void SharedFunctionInfo::ForbidInlineConstructor() {
set_compiler_hints(BooleanBit::set(compiler_hints(),
kHasOnlySimpleThisPropertyAssignments,
false));
}
void SharedFunctionInfo::SetThisPropertyAssignmentsInfo(
bool only_simple_this_property_assignments,
FixedArray* assignments) {
set_compiler_hints(BooleanBit::set(compiler_hints(),
kHasOnlySimpleThisPropertyAssignments,
only_simple_this_property_assignments));
set_this_property_assignments(assignments);
set_this_property_assignments_count(assignments->length() / 3);
}
void SharedFunctionInfo::ClearThisPropertyAssignmentsInfo() {
Heap* heap = GetHeap();
set_compiler_hints(BooleanBit::set(compiler_hints(),
kHasOnlySimpleThisPropertyAssignments,
false));
set_this_property_assignments(heap->undefined_value());
set_this_property_assignments_count(0);
}
String* SharedFunctionInfo::GetThisPropertyAssignmentName(int index) {
Object* obj = this_property_assignments();
ASSERT(obj->IsFixedArray());
ASSERT(index < this_property_assignments_count());
obj = FixedArray::cast(obj)->get(index * 3);
ASSERT(obj->IsString());
return String::cast(obj);
}
bool SharedFunctionInfo::IsThisPropertyAssignmentArgument(int index) {
Object* obj = this_property_assignments();
ASSERT(obj->IsFixedArray());
ASSERT(index < this_property_assignments_count());
obj = FixedArray::cast(obj)->get(index * 3 + 1);
return Smi::cast(obj)->value() != -1;
}
int SharedFunctionInfo::GetThisPropertyAssignmentArgument(int index) {
ASSERT(IsThisPropertyAssignmentArgument(index));
Object* obj =
FixedArray::cast(this_property_assignments())->get(index * 3 + 1);
return Smi::cast(obj)->value();
}
Object* SharedFunctionInfo::GetThisPropertyAssignmentConstant(int index) {
ASSERT(!IsThisPropertyAssignmentArgument(index));
Object* obj =
FixedArray::cast(this_property_assignments())->get(index * 3 + 2);
return obj;
}
// Support function for printing the source code to a StringStream
// without any allocation in the heap.
void SharedFunctionInfo::SourceCodePrint(StringStream* accumulator,
int max_length) {
// For some native functions there is no source.
if (!HasSourceCode()) {
accumulator->Add("<No Source>");
return;
}
// Get the source for the script which this function came from.
// Don't use String::cast because we don't want more assertion errors while
// we are already creating a stack dump.
String* script_source =
reinterpret_cast<String*>(Script::cast(script())->source());
if (!script_source->LooksValid()) {
accumulator->Add("<Invalid Source>");
return;
}
if (!is_toplevel()) {
accumulator->Add("function ");
Object* name = this->name();
if (name->IsString() && String::cast(name)->length() > 0) {
accumulator->PrintName(name);
}
}
int len = end_position() - start_position();
if (len <= max_length || max_length < 0) {
accumulator->Put(script_source, start_position(), end_position());
} else {
accumulator->Put(script_source,
start_position(),
start_position() + max_length);
accumulator->Add("...\n");
}
}
static bool IsCodeEquivalent(Code* code, Code* recompiled) {
if (code->instruction_size() != recompiled->instruction_size()) return false;
ByteArray* code_relocation = code->relocation_info();
ByteArray* recompiled_relocation = recompiled->relocation_info();
int length = code_relocation->length();
if (length != recompiled_relocation->length()) return false;
int compare = memcmp(code_relocation->GetDataStartAddress(),
recompiled_relocation->GetDataStartAddress(),
length);
return compare == 0;
}
void SharedFunctionInfo::EnableDeoptimizationSupport(Code* recompiled) {
ASSERT(!has_deoptimization_support());
AssertNoAllocation no_allocation;
Code* code = this->code();
if (IsCodeEquivalent(code, recompiled)) {
// Copy the deoptimization data from the recompiled code.
code->set_deoptimization_data(recompiled->deoptimization_data());
code->set_has_deoptimization_support(true);
} else {
// TODO(3025757): In case the recompiled isn't equivalent to the
// old code, we have to replace it. We should try to avoid this
// altogether because it flushes valuable type feedback by
// effectively resetting all IC state.
set_code(recompiled);
}
ASSERT(has_deoptimization_support());
}
void SharedFunctionInfo::DisableOptimization() {
// Disable optimization for the shared function info and mark the
// code as non-optimizable. The marker on the shared function info
// is there because we flush non-optimized code thereby loosing the
// non-optimizable information for the code. When the code is
// regenerated and set on the shared function info it is marked as
// non-optimizable if optimization is disabled for the shared
// function info.
set_optimization_disabled(true);
// Code should be the lazy compilation stub or else unoptimized. If the
// latter, disable optimization for the code too.
ASSERT(code()->kind() == Code::FUNCTION || code()->kind() == Code::BUILTIN);
if (code()->kind() == Code::FUNCTION) {
code()->set_optimizable(false);
}
if (FLAG_trace_opt) {
PrintF("[disabled optimization for %s]\n", *DebugName()->ToCString());
}
}
bool SharedFunctionInfo::VerifyBailoutId(int id) {
ASSERT(id != AstNode::kNoNumber);
Code* unoptimized = code();
DeoptimizationOutputData* data =
DeoptimizationOutputData::cast(unoptimized->deoptimization_data());
unsigned ignore = Deoptimizer::GetOutputInfo(data, id, this);
USE(ignore);
return true; // Return true if there was no ASSERT.
}
void SharedFunctionInfo::StartInobjectSlackTracking(Map* map) {
ASSERT(!IsInobjectSlackTrackingInProgress());
if (!FLAG_clever_optimizations) return;
// Only initiate the tracking the first time.
if (live_objects_may_exist()) return;
set_live_objects_may_exist(true);
// No tracking during the snapshot construction phase.
if (Serializer::enabled()) return;
if (map->unused_property_fields() == 0) return;
// Nonzero counter is a leftover from the previous attempt interrupted
// by GC, keep it.
if (construction_count() == 0) {
set_construction_count(kGenerousAllocationCount);
}
set_initial_map(map);
Builtins* builtins = map->GetHeap()->isolate()->builtins();
ASSERT_EQ(builtins->builtin(Builtins::kJSConstructStubGeneric),
construct_stub());
set_construct_stub(builtins->builtin(Builtins::kJSConstructStubCountdown));
}
// Called from GC, hence reinterpret_cast and unchecked accessors.
void SharedFunctionInfo::DetachInitialMap() {
Map* map = reinterpret_cast<Map*>(initial_map());
// Make the map remember to restore the link if it survives the GC.
map->set_bit_field2(
map->bit_field2() | (1 << Map::kAttachedToSharedFunctionInfo));
// Undo state changes made by StartInobjectTracking (except the
// construction_count). This way if the initial map does not survive the GC
// then StartInobjectTracking will be called again the next time the
// constructor is called. The countdown will continue and (possibly after
// several more GCs) CompleteInobjectSlackTracking will eventually be called.
Heap* heap = map->GetHeap();
set_initial_map(heap->raw_unchecked_undefined_value());
Builtins* builtins = heap->isolate()->builtins();
ASSERT_EQ(builtins->builtin(Builtins::kJSConstructStubCountdown),
*RawField(this, kConstructStubOffset));
set_construct_stub(builtins->builtin(Builtins::kJSConstructStubGeneric));
// It is safe to clear the flag: it will be set again if the map is live.
set_live_objects_may_exist(false);
}
// Called from GC, hence reinterpret_cast and unchecked accessors.
void SharedFunctionInfo::AttachInitialMap(Map* map) {
map->set_bit_field2(
map->bit_field2() & ~(1 << Map::kAttachedToSharedFunctionInfo));
// Resume inobject slack tracking.
set_initial_map(map);
Builtins* builtins = map->GetHeap()->isolate()->builtins();
ASSERT_EQ(builtins->builtin(Builtins::kJSConstructStubGeneric),
*RawField(this, kConstructStubOffset));
set_construct_stub(builtins->builtin(Builtins::kJSConstructStubCountdown));
// The map survived the gc, so there may be objects referencing it.
set_live_objects_may_exist(true);
}
void SharedFunctionInfo::ResetForNewContext(int new_ic_age) {
code()->ClearInlineCaches();
set_ic_age(new_ic_age);
if (code()->kind() == Code::FUNCTION) {
code()->set_profiler_ticks(0);
if (optimization_disabled() &&
opt_count() >= Compiler::kDefaultMaxOptCount) {
// Re-enable optimizations if they were disabled due to opt_count limit.
set_optimization_disabled(false);
code()->set_optimizable(true);
}
set_opt_count(0);
}
}
static void GetMinInobjectSlack(Map* map, void* data) {
int slack = map->unused_property_fields();
if (*reinterpret_cast<int*>(data) > slack) {
*reinterpret_cast<int*>(data) = slack;
}
}
static void ShrinkInstanceSize(Map* map, void* data) {
int slack = *reinterpret_cast<int*>(data);
map->set_inobject_properties(map->inobject_properties() - slack);
map->set_unused_property_fields(map->unused_property_fields() - slack);
map->set_instance_size(map->instance_size() - slack * kPointerSize);
// Visitor id might depend on the instance size, recalculate it.
map->set_visitor_id(StaticVisitorBase::GetVisitorId(map));
}
void SharedFunctionInfo::CompleteInobjectSlackTracking() {
ASSERT(live_objects_may_exist() && IsInobjectSlackTrackingInProgress());
Map* map = Map::cast(initial_map());
Heap* heap = map->GetHeap();
set_initial_map(heap->undefined_value());
Builtins* builtins = heap->isolate()->builtins();
ASSERT_EQ(builtins->builtin(Builtins::kJSConstructStubCountdown),
construct_stub());
set_construct_stub(builtins->builtin(Builtins::kJSConstructStubGeneric));
int slack = map->unused_property_fields();
map->TraverseTransitionTree(&GetMinInobjectSlack, &slack);
if (slack != 0) {
// Resize the initial map and all maps in its transition tree.
map->TraverseTransitionTree(&ShrinkInstanceSize, &slack);
// Give the correct expected_nof_properties to initial maps created later.
ASSERT(expected_nof_properties() >= slack);
set_expected_nof_properties(expected_nof_properties() - slack);
}
}
void SharedFunctionInfo::SharedFunctionInfoIterateBody(ObjectVisitor* v) {
v->VisitSharedFunctionInfo(this);
SharedFunctionInfo::BodyDescriptor::IterateBody(this, v);
}
#define DECLARE_TAG(ignore1, name, ignore2) name,
const char* const VisitorSynchronization::kTags[
VisitorSynchronization::kNumberOfSyncTags] = {
VISITOR_SYNCHRONIZATION_TAGS_LIST(DECLARE_TAG)
};
#undef DECLARE_TAG
#define DECLARE_TAG(ignore1, ignore2, name) name,
const char* const VisitorSynchronization::kTagNames[
VisitorSynchronization::kNumberOfSyncTags] = {
VISITOR_SYNCHRONIZATION_TAGS_LIST(DECLARE_TAG)
};
#undef DECLARE_TAG
void ObjectVisitor::VisitCodeTarget(RelocInfo* rinfo) {
ASSERT(RelocInfo::IsCodeTarget(rinfo->rmode()));
Object* target = Code::GetCodeFromTargetAddress(rinfo->target_address());
Object* old_target = target;
VisitPointer(&target);
CHECK_EQ(target, old_target); // VisitPointer doesn't change Code* *target.
}
void ObjectVisitor::VisitCodeEntry(Address entry_address) {
Object* code = Code::GetObjectFromEntryAddress(entry_address);
Object* old_code = code;
VisitPointer(&code);
if (code != old_code) {
Memory::Address_at(entry_address) = reinterpret_cast<Code*>(code)->entry();
}
}
void ObjectVisitor::VisitGlobalPropertyCell(RelocInfo* rinfo) {
ASSERT(rinfo->rmode() == RelocInfo::GLOBAL_PROPERTY_CELL);
Object* cell = rinfo->target_cell();
Object* old_cell = cell;
VisitPointer(&cell);
if (cell != old_cell) {
rinfo->set_target_cell(reinterpret_cast<JSGlobalPropertyCell*>(cell));
}
}
void ObjectVisitor::VisitDebugTarget(RelocInfo* rinfo) {
ASSERT((RelocInfo::IsJSReturn(rinfo->rmode()) &&
rinfo->IsPatchedReturnSequence()) ||
(RelocInfo::IsDebugBreakSlot(rinfo->rmode()) &&
rinfo->IsPatchedDebugBreakSlotSequence()));
Object* target = Code::GetCodeFromTargetAddress(rinfo->call_address());
Object* old_target = target;
VisitPointer(&target);
CHECK_EQ(target, old_target); // VisitPointer doesn't change Code* *target.
}
void ObjectVisitor::VisitEmbeddedPointer(RelocInfo* rinfo) {
ASSERT(rinfo->rmode() == RelocInfo::EMBEDDED_OBJECT);
VisitPointer(rinfo->target_object_address());
}
void ObjectVisitor::VisitExternalReference(RelocInfo* rinfo) {
Address* p = rinfo->target_reference_address();
VisitExternalReferences(p, p + 1);
}
void Code::InvalidateRelocation() {
set_relocation_info(GetHeap()->empty_byte_array());
}
void Code::Relocate(intptr_t delta) {
for (RelocIterator it(this, RelocInfo::kApplyMask); !it.done(); it.next()) {
it.rinfo()->apply(delta);
}
CPU::FlushICache(instruction_start(), instruction_size());
}
void Code::CopyFrom(const CodeDesc& desc) {
ASSERT(Marking::Color(this) == Marking::WHITE_OBJECT);
// copy code
memmove(instruction_start(), desc.buffer, desc.instr_size);
// copy reloc info
memmove(relocation_start(),
desc.buffer + desc.buffer_size - desc.reloc_size,
desc.reloc_size);
// unbox handles and relocate
intptr_t delta = instruction_start() - desc.buffer;
int mode_mask = RelocInfo::kCodeTargetMask |
RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::GLOBAL_PROPERTY_CELL) |
RelocInfo::kApplyMask;
Assembler* origin = desc.origin; // Needed to find target_object on X64.
for (RelocIterator it(this, mode_mask); !it.done(); it.next()) {
RelocInfo::Mode mode = it.rinfo()->rmode();
if (mode == RelocInfo::EMBEDDED_OBJECT) {
Handle<Object> p = it.rinfo()->target_object_handle(origin);
it.rinfo()->set_target_object(*p, SKIP_WRITE_BARRIER);
} else if (mode == RelocInfo::GLOBAL_PROPERTY_CELL) {
Handle<JSGlobalPropertyCell> cell = it.rinfo()->target_cell_handle();
it.rinfo()->set_target_cell(*cell, SKIP_WRITE_BARRIER);
} else if (RelocInfo::IsCodeTarget(mode)) {
// rewrite code handles in inline cache targets to direct
// pointers to the first instruction in the code object
Handle<Object> p = it.rinfo()->target_object_handle(origin);
Code* code = Code::cast(*p);
it.rinfo()->set_target_address(code->instruction_start(),
SKIP_WRITE_BARRIER);
} else {
it.rinfo()->apply(delta);
}
}
CPU::FlushICache(instruction_start(), instruction_size());
}
// Locate the source position which is closest to the address in the code. This
// is using the source position information embedded in the relocation info.
// The position returned is relative to the beginning of the script where the
// source for this function is found.
int Code::SourcePosition(Address pc) {
int distance = kMaxInt;
int position = RelocInfo::kNoPosition; // Initially no position found.
// Run through all the relocation info to find the best matching source
// position. All the code needs to be considered as the sequence of the
// instructions in the code does not necessarily follow the same order as the
// source.
RelocIterator it(this, RelocInfo::kPositionMask);
while (!it.done()) {
// Only look at positions after the current pc.
if (it.rinfo()->pc() < pc) {
// Get position and distance.
int dist = static_cast<int>(pc - it.rinfo()->pc());
int pos = static_cast<int>(it.rinfo()->data());
// If this position is closer than the current candidate or if it has the
// same distance as the current candidate and the position is higher then
// this position is the new candidate.
if ((dist < distance) ||
(dist == distance && pos > position)) {
position = pos;
distance = dist;
}
}
it.next();
}
return position;
}
// Same as Code::SourcePosition above except it only looks for statement
// positions.
int Code::SourceStatementPosition(Address pc) {
// First find the position as close as possible using all position
// information.
int position = SourcePosition(pc);
// Now find the closest statement position before the position.
int statement_position = 0;
RelocIterator it(this, RelocInfo::kPositionMask);
while (!it.done()) {
if (RelocInfo::IsStatementPosition(it.rinfo()->rmode())) {
int p = static_cast<int>(it.rinfo()->data());
if (statement_position < p && p <= position) {
statement_position = p;
}
}
it.next();
}
return statement_position;
}
SafepointEntry Code::GetSafepointEntry(Address pc) {
SafepointTable table(this);
return table.FindEntry(pc);
}
void Code::SetNoStackCheckTable() {
// Indicate the absence of a stack-check table by a table start after the
// end of the instructions. Table start must be aligned, so round up.
set_stack_check_table_offset(RoundUp(instruction_size(), kIntSize));
}
Map* Code::FindFirstMap() {
ASSERT(is_inline_cache_stub());
AssertNoAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Object* object = info->target_object();
if (object->IsMap()) return Map::cast(object);
}
return NULL;
}
void Code::ClearInlineCaches() {
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
RelocInfo::ModeMask(RelocInfo::CONSTRUCT_CALL) |
RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID) |
RelocInfo::ModeMask(RelocInfo::CODE_TARGET_CONTEXT);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Code* target(Code::GetCodeFromTargetAddress(info->target_address()));
if (target->is_inline_cache_stub()) {
IC::Clear(info->pc());
}
}
}
#ifdef ENABLE_DISASSEMBLER
void DeoptimizationInputData::DeoptimizationInputDataPrint(FILE* out) {
disasm::NameConverter converter;
int deopt_count = DeoptCount();
PrintF(out, "Deoptimization Input Data (deopt points = %d)\n", deopt_count);
if (0 == deopt_count) return;
PrintF(out, "%6s %6s %6s %6s %12s\n", "index", "ast id", "argc", "pc",
FLAG_print_code_verbose ? "commands" : "");
for (int i = 0; i < deopt_count; i++) {
PrintF(out, "%6d %6d %6d %6d",
i,
AstId(i)->value(),
ArgumentsStackHeight(i)->value(),
Pc(i)->value());
if (!FLAG_print_code_verbose) {
PrintF(out, "\n");
continue;
}
// Print details of the frame translation.
int translation_index = TranslationIndex(i)->value();
TranslationIterator iterator(TranslationByteArray(), translation_index);
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator.Next());
ASSERT(Translation::BEGIN == opcode);
int frame_count = iterator.Next();
int jsframe_count = iterator.Next();
PrintF(out, " %s {frame count=%d, js frame count=%d}\n",
Translation::StringFor(opcode),
frame_count,
jsframe_count);
while (iterator.HasNext() &&
Translation::BEGIN !=
(opcode = static_cast<Translation::Opcode>(iterator.Next()))) {
PrintF(out, "%24s %s ", "", Translation::StringFor(opcode));
switch (opcode) {
case Translation::BEGIN:
UNREACHABLE();
break;
case Translation::JS_FRAME: {
int ast_id = iterator.Next();
int function_id = iterator.Next();
JSFunction* function =
JSFunction::cast(LiteralArray()->get(function_id));
unsigned height = iterator.Next();
PrintF(out, "{ast_id=%d, function=", ast_id);
function->PrintName(out);
PrintF(out, ", height=%u}", height);
break;
}
case Translation::ARGUMENTS_ADAPTOR_FRAME:
case Translation::CONSTRUCT_STUB_FRAME: {
int function_id = iterator.Next();
JSFunction* function =
JSFunction::cast(LiteralArray()->get(function_id));
unsigned height = iterator.Next();
PrintF(out, "{function=");
function->PrintName(out);
PrintF(out, ", height=%u}", height);
break;
}
case Translation::DUPLICATE:
break;
case Translation::REGISTER: {
int reg_code = iterator.Next();
PrintF(out, "{input=%s}", converter.NameOfCPURegister(reg_code));
break;
}
case Translation::INT32_REGISTER: {
int reg_code = iterator.Next();
PrintF(out, "{input=%s}", converter.NameOfCPURegister(reg_code));
break;
}
case Translation::DOUBLE_REGISTER: {
int reg_code = iterator.Next();
PrintF(out, "{input=%s}",
DoubleRegister::AllocationIndexToString(reg_code));
break;
}
case Translation::STACK_SLOT: {
int input_slot_index = iterator.Next();
PrintF(out, "{input=%d}", input_slot_index);
break;
}
case Translation::INT32_STACK_SLOT: {
int input_slot_index = iterator.Next();
PrintF(out, "{input=%d}", input_slot_index);
break;
}
case Translation::DOUBLE_STACK_SLOT: {
int input_slot_index = iterator.Next();
PrintF(out, "{input=%d}", input_slot_index);
break;
}
case Translation::LITERAL: {
unsigned literal_index = iterator.Next();
PrintF(out, "{literal_id=%u}", literal_index);
break;
}
case Translation::ARGUMENTS_OBJECT:
break;
}
PrintF(out, "\n");
}
}
}
void DeoptimizationOutputData::DeoptimizationOutputDataPrint(FILE* out) {
PrintF(out, "Deoptimization Output Data (deopt points = %d)\n",
this->DeoptPoints());
if (this->DeoptPoints() == 0) return;
PrintF("%6s %8s %s\n", "ast id", "pc", "state");
for (int i = 0; i < this->DeoptPoints(); i++) {
int pc_and_state = this->PcAndState(i)->value();
PrintF("%6d %8d %s\n",
this->AstId(i)->value(),
FullCodeGenerator::PcField::decode(pc_and_state),
FullCodeGenerator::State2String(
FullCodeGenerator::StateField::decode(pc_and_state)));
}
}
// Identify kind of code.
const char* Code::Kind2String(Kind kind) {
switch (kind) {
case FUNCTION: return "FUNCTION";
case OPTIMIZED_FUNCTION: return "OPTIMIZED_FUNCTION";
case STUB: return "STUB";
case BUILTIN: return "BUILTIN";
case LOAD_IC: return "LOAD_IC";
case KEYED_LOAD_IC: return "KEYED_LOAD_IC";
case STORE_IC: return "STORE_IC";
case KEYED_STORE_IC: return "KEYED_STORE_IC";
case CALL_IC: return "CALL_IC";
case KEYED_CALL_IC: return "KEYED_CALL_IC";
case UNARY_OP_IC: return "UNARY_OP_IC";
case BINARY_OP_IC: return "BINARY_OP_IC";
case COMPARE_IC: return "COMPARE_IC";
case TO_BOOLEAN_IC: return "TO_BOOLEAN_IC";
}
UNREACHABLE();
return NULL;
}
const char* Code::ICState2String(InlineCacheState state) {
switch (state) {
case UNINITIALIZED: return "UNINITIALIZED";
case PREMONOMORPHIC: return "PREMONOMORPHIC";
case MONOMORPHIC: return "MONOMORPHIC";
case MONOMORPHIC_PROTOTYPE_FAILURE: return "MONOMORPHIC_PROTOTYPE_FAILURE";
case MEGAMORPHIC: return "MEGAMORPHIC";
case DEBUG_BREAK: return "DEBUG_BREAK";
case DEBUG_PREPARE_STEP_IN: return "DEBUG_PREPARE_STEP_IN";
}
UNREACHABLE();
return NULL;
}
const char* Code::PropertyType2String(PropertyType type) {
switch (type) {
case NORMAL: return "NORMAL";
case FIELD: return "FIELD";
case CONSTANT_FUNCTION: return "CONSTANT_FUNCTION";
case CALLBACKS: return "CALLBACKS";
case HANDLER: return "HANDLER";
case INTERCEPTOR: return "INTERCEPTOR";
case MAP_TRANSITION: return "MAP_TRANSITION";
case ELEMENTS_TRANSITION: return "ELEMENTS_TRANSITION";
case CONSTANT_TRANSITION: return "CONSTANT_TRANSITION";
case NULL_DESCRIPTOR: return "NULL_DESCRIPTOR";
}
UNREACHABLE(); // keep the compiler happy
return NULL;
}
void Code::PrintExtraICState(FILE* out, Kind kind, ExtraICState extra) {
const char* name = NULL;
switch (kind) {
case CALL_IC:
if (extra == STRING_INDEX_OUT_OF_BOUNDS) {
name = "STRING_INDEX_OUT_OF_BOUNDS";
}
break;
case STORE_IC:
case KEYED_STORE_IC:
if (extra == kStrictMode) {
name = "STRICT";
}
break;
default:
break;
}
if (name != NULL) {
PrintF(out, "extra_ic_state = %s\n", name);
} else {
PrintF(out, "extra_ic_state = %d\n", extra);
}
}
void Code::Disassemble(const char* name, FILE* out) {
PrintF(out, "kind = %s\n", Kind2String(kind()));
if (is_inline_cache_stub()) {
PrintF(out, "ic_state = %s\n", ICState2String(ic_state()));
PrintExtraICState(out, kind(), extra_ic_state());
if (ic_state() == MONOMORPHIC) {
PrintF(out, "type = %s\n", PropertyType2String(type()));
}
if (is_call_stub() || is_keyed_call_stub()) {
PrintF(out, "argc = %d\n", arguments_count());
}
}
if ((name != NULL) && (name[0] != '\0')) {
PrintF(out, "name = %s\n", name);
}
if (kind() == OPTIMIZED_FUNCTION) {
PrintF(out, "stack_slots = %d\n", stack_slots());
}
PrintF(out, "Instructions (size = %d)\n", instruction_size());
Disassembler::Decode(out, this);
PrintF(out, "\n");
if (kind() == FUNCTION) {
DeoptimizationOutputData* data =
DeoptimizationOutputData::cast(this->deoptimization_data());
data->DeoptimizationOutputDataPrint(out);
} else if (kind() == OPTIMIZED_FUNCTION) {
DeoptimizationInputData* data =
DeoptimizationInputData::cast(this->deoptimization_data());
data->DeoptimizationInputDataPrint(out);
}
PrintF("\n");
if (kind() == OPTIMIZED_FUNCTION) {
SafepointTable table(this);
PrintF(out, "Safepoints (size = %u)\n", table.size());
for (unsigned i = 0; i < table.length(); i++) {
unsigned pc_offset = table.GetPcOffset(i);
PrintF(out, "%p %4d ", (instruction_start() + pc_offset), pc_offset);
table.PrintEntry(i);
PrintF(out, " (sp -> fp)");
SafepointEntry entry = table.GetEntry(i);
if (entry.deoptimization_index() != Safepoint::kNoDeoptimizationIndex) {
PrintF(out, " %6d", entry.deoptimization_index());
} else {
PrintF(out, " <none>");
}
if (entry.argument_count() > 0) {
PrintF(out, " argc: %d", entry.argument_count());
}
PrintF(out, "\n");
}
PrintF(out, "\n");
} else if (kind() == FUNCTION) {
unsigned offset = stack_check_table_offset();
// If there is no stack check table, the "table start" will at or after
// (due to alignment) the end of the instruction stream.
if (static_cast<int>(offset) < instruction_size()) {
unsigned* address =
reinterpret_cast<unsigned*>(instruction_start() + offset);
unsigned length = address[0];
PrintF(out, "Stack checks (size = %u)\n", length);
PrintF(out, "ast_id pc_offset\n");
for (unsigned i = 0; i < length; ++i) {
unsigned index = (2 * i) + 1;
PrintF(out, "%6u %9u\n", address[index], address[index + 1]);
}
PrintF(out, "\n");
}
}
PrintF("RelocInfo (size = %d)\n", relocation_size());
for (RelocIterator it(this); !it.done(); it.next()) it.rinfo()->Print(out);
PrintF(out, "\n");
}
#endif // ENABLE_DISASSEMBLER
MaybeObject* JSObject::SetFastElementsCapacityAndLength(
int capacity,
int length,
SetFastElementsCapacityMode set_capacity_mode) {
Heap* heap = GetHeap();
// We should never end in here with a pixel or external array.
ASSERT(!HasExternalArrayElements());
// Allocate a new fast elements backing store.
FixedArray* new_elements;
{ MaybeObject* maybe = heap->AllocateFixedArrayWithHoles(capacity);
if (!maybe->To(&new_elements)) return maybe;
}
// Find the new map to use for this object if there is a map change.
Map* new_map = NULL;
if (elements()->map() != heap->non_strict_arguments_elements_map()) {
// The resized array has FAST_SMI_ONLY_ELEMENTS if the capacity mode forces
// it, or if it's allowed and the old elements array contained only SMIs.
bool has_fast_smi_only_elements =
(set_capacity_mode == kForceSmiOnlyElements) ||
((set_capacity_mode == kAllowSmiOnlyElements) &&
(elements()->map()->has_fast_smi_only_elements() ||
elements() == heap->empty_fixed_array()));
ElementsKind elements_kind = has_fast_smi_only_elements
? FAST_SMI_ONLY_ELEMENTS
: FAST_ELEMENTS;
MaybeObject* maybe = GetElementsTransitionMap(GetIsolate(), elements_kind);
if (!maybe->To(&new_map)) return maybe;
}
FixedArrayBase* old_elements = elements();
ElementsKind elements_kind = GetElementsKind();
ElementsAccessor* accessor = ElementsAccessor::ForKind(elements_kind);
ElementsKind to_kind = (elements_kind == FAST_SMI_ONLY_ELEMENTS)
? FAST_SMI_ONLY_ELEMENTS
: FAST_ELEMENTS;
// int copy_size = Min(old_elements_raw->length(), new_elements->length());
accessor->CopyElements(this, new_elements, to_kind);
if (elements_kind != NON_STRICT_ARGUMENTS_ELEMENTS) {
set_map_and_elements(new_map, new_elements);
} else {
FixedArray* parameter_map = FixedArray::cast(old_elements);
parameter_map->set(1, new_elements);
}
if (FLAG_trace_elements_transitions) {
PrintElementsTransition(stdout, elements_kind, old_elements,
GetElementsKind(), new_elements);
}
// Update the length if necessary.
if (IsJSArray()) {
JSArray::cast(this)->set_length(Smi::FromInt(length));
}
return new_elements;
}
MaybeObject* JSObject::SetFastDoubleElementsCapacityAndLength(
int capacity,
int length) {
Heap* heap = GetHeap();
// We should never end in here with a pixel or external array.
ASSERT(!HasExternalArrayElements());
FixedArrayBase* elems;
{ MaybeObject* maybe_obj =
heap->AllocateUninitializedFixedDoubleArray(capacity);
if (!maybe_obj->To(&elems)) return maybe_obj;
}
Map* new_map;
{ MaybeObject* maybe_obj =
GetElementsTransitionMap(heap->isolate(), FAST_DOUBLE_ELEMENTS);
if (!maybe_obj->To(&new_map)) return maybe_obj;
}
FixedArrayBase* old_elements = elements();
ElementsKind elements_kind = GetElementsKind();
ElementsAccessor* accessor = ElementsAccessor::ForKind(elements_kind);
accessor->CopyElements(this, elems, FAST_DOUBLE_ELEMENTS);
if (elements_kind != NON_STRICT_ARGUMENTS_ELEMENTS) {
set_map_and_elements(new_map, elems);
} else {
FixedArray* parameter_map = FixedArray::cast(old_elements);
parameter_map->set(1, elems);
}
if (FLAG_trace_elements_transitions) {
PrintElementsTransition(stdout, elements_kind, old_elements,
FAST_DOUBLE_ELEMENTS, elems);
}
if (IsJSArray()) {
JSArray::cast(this)->set_length(Smi::FromInt(length));
}
return this;
}
MaybeObject* JSArray::Initialize(int capacity) {
Heap* heap = GetHeap();
ASSERT(capacity >= 0);
set_length(Smi::FromInt(0));
FixedArray* new_elements;
if (capacity == 0) {
new_elements = heap->empty_fixed_array();
} else {
MaybeObject* maybe_obj = heap->AllocateFixedArrayWithHoles(capacity);
if (!maybe_obj->To(&new_elements)) return maybe_obj;
}
set_elements(new_elements);
return this;
}
void JSArray::Expand(int required_size) {
GetIsolate()->factory()->SetElementsCapacityAndLength(
Handle<JSArray>(this), required_size, required_size);
}
MaybeObject* JSArray::SetElementsLength(Object* len) {
// We should never end in here with a pixel or external array.
ASSERT(AllowsSetElementsLength());
return GetElementsAccessor()->SetLength(this, len);
}
Object* Map::GetPrototypeTransition(Object* prototype) {
FixedArray* cache = prototype_transitions();
int number_of_transitions = NumberOfProtoTransitions();
const int proto_offset =
kProtoTransitionHeaderSize + kProtoTransitionPrototypeOffset;
const int map_offset = kProtoTransitionHeaderSize + kProtoTransitionMapOffset;
const int step = kProtoTransitionElementsPerEntry;
for (int i = 0; i < number_of_transitions; i++) {
if (cache->get(proto_offset + i * step) == prototype) {
Object* map = cache->get(map_offset + i * step);
ASSERT(map->IsMap());
return map;
}
}
return NULL;
}
MaybeObject* Map::PutPrototypeTransition(Object* prototype, Map* map) {
ASSERT(map->IsMap());
ASSERT(HeapObject::cast(prototype)->map()->IsMap());
// Don't cache prototype transition if this map is shared.
if (is_shared() || !FLAG_cache_prototype_transitions) return this;
FixedArray* cache = prototype_transitions();
const int step = kProtoTransitionElementsPerEntry;
const int header = kProtoTransitionHeaderSize;
int capacity = (cache->length() - header) / step;
int transitions = NumberOfProtoTransitions() + 1;
if (transitions > capacity) {
if (capacity > kMaxCachedPrototypeTransitions) return this;
FixedArray* new_cache;
// Grow array by factor 2 over and above what we need.
{ MaybeObject* maybe_cache =
GetHeap()->AllocateFixedArray(transitions * 2 * step + header);
if (!maybe_cache->To(&new_cache)) return maybe_cache;
}
for (int i = 0; i < capacity * step; i++) {
new_cache->set(i + header, cache->get(i + header));
}
cache = new_cache;
set_prototype_transitions(cache);
}
int last = transitions - 1;
cache->set(header + last * step + kProtoTransitionPrototypeOffset, prototype);
cache->set(header + last * step + kProtoTransitionMapOffset, map);
SetNumberOfProtoTransitions(transitions);
return cache;
}
MaybeObject* JSReceiver::SetPrototype(Object* value,
bool skip_hidden_prototypes) {
#ifdef DEBUG
int size = Size();
#endif
Heap* heap = GetHeap();
// Silently ignore the change if value is not a JSObject or null.
// SpiderMonkey behaves this way.
if (!value->IsJSReceiver() && !value->IsNull()) return value;
// From 8.6.2 Object Internal Methods
// ...
// In addition, if [[Extensible]] is false the value of the [[Class]] and
// [[Prototype]] internal properties of the object may not be modified.
// ...
// Implementation specific extensions that modify [[Class]], [[Prototype]]
// or [[Extensible]] must not violate the invariants defined in the preceding
// paragraph.
if (!this->map()->is_extensible()) {
HandleScope scope(heap->isolate());
Handle<Object> handle(this, heap->isolate());
return heap->isolate()->Throw(
*FACTORY->NewTypeError("non_extensible_proto",
HandleVector<Object>(&handle, 1)));
}
// Before we can set the prototype we need to be sure
// prototype cycles are prevented.
// It is sufficient to validate that the receiver is not in the new prototype
// chain.
for (Object* pt = value; pt != heap->null_value(); pt = pt->GetPrototype()) {
if (JSReceiver::cast(pt) == this) {
// Cycle detected.
HandleScope scope(heap->isolate());
return heap->isolate()->Throw(
*FACTORY->NewError("cyclic_proto", HandleVector<Object>(NULL, 0)));
}
}
JSReceiver* real_receiver = this;
if (skip_hidden_prototypes) {
// Find the first object in the chain whose prototype object is not
// hidden and set the new prototype on that object.
Object* current_proto = real_receiver->GetPrototype();
while (current_proto->IsJSObject() &&
JSReceiver::cast(current_proto)->map()->is_hidden_prototype()) {
real_receiver = JSReceiver::cast(current_proto);
current_proto = current_proto->GetPrototype();
}
}
// Set the new prototype of the object.
Map* map = real_receiver->map();
// Nothing to do if prototype is already set.
if (map->prototype() == value) return value;
Object* new_map = map->GetPrototypeTransition(value);
if (new_map == NULL) {
{ MaybeObject* maybe_new_map = map->CopyDropTransitions();
if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
}
{ MaybeObject* maybe_new_cache =
map->PutPrototypeTransition(value, Map::cast(new_map));
if (maybe_new_cache->IsFailure()) return maybe_new_cache;
}
Map::cast(new_map)->set_prototype(value);
}
ASSERT(Map::cast(new_map)->prototype() == value);
real_receiver->set_map(Map::cast(new_map));
heap->ClearInstanceofCache();
ASSERT(size == Size());
return value;
}
MaybeObject* JSObject::EnsureCanContainElements(Arguments* args,
uint32_t first_arg,
uint32_t arg_count,
EnsureElementsMode mode) {
// Elements in |Arguments| are ordered backwards (because they're on the
// stack), but the method that's called here iterates over them in forward
// direction.
return EnsureCanContainElements(
args->arguments() - first_arg - (arg_count - 1),
arg_count, mode);
}
bool JSObject::HasElementWithInterceptor(JSReceiver* receiver, uint32_t index) {
Isolate* isolate = GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetIndexedInterceptor());
Handle<JSReceiver> receiver_handle(receiver);
Handle<JSObject> holder_handle(this);
CustomArguments args(isolate, interceptor->data(), receiver, this);
v8::AccessorInfo info(args.end());
if (!interceptor->query()->IsUndefined()) {
v8::IndexedPropertyQuery query =
v8::ToCData<v8::IndexedPropertyQuery>(interceptor->query());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-has", this, index));
v8::Handle<v8::Integer> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = query(index, info);
}
if (!result.IsEmpty()) {
ASSERT(result->IsInt32());
return true; // absence of property is signaled by empty handle.
}
} else if (!interceptor->getter()->IsUndefined()) {
v8::IndexedPropertyGetter getter =
v8::ToCData<v8::IndexedPropertyGetter>(interceptor->getter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-has-get", this, index));
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = getter(index, info);
}
if (!result.IsEmpty()) return true;
}
if (holder_handle->GetElementsAccessor()->HasElement(
*receiver_handle, *holder_handle, index)) {
return true;
}
if (holder_handle->IsStringObjectWithCharacterAt(index)) return true;
Object* pt = holder_handle->GetPrototype();
if (pt->IsJSProxy()) {
// We need to follow the spec and simulate a call to [[GetOwnProperty]].
return JSProxy::cast(pt)->GetElementAttributeWithHandler(
receiver, index) != ABSENT;
}
if (pt->IsNull()) return false;
return JSObject::cast(pt)->HasElementWithReceiver(*receiver_handle, index);
}
JSObject::LocalElementType JSObject::HasLocalElement(uint32_t index) {
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
Heap* heap = GetHeap();
if (!heap->isolate()->MayIndexedAccess(this, index, v8::ACCESS_HAS)) {
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return UNDEFINED_ELEMENT;
}
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return UNDEFINED_ELEMENT;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->HasLocalElement(index);
}
// Check for lookup interceptor
if (HasIndexedInterceptor()) {
return HasElementWithInterceptor(this, index) ? INTERCEPTED_ELEMENT
: UNDEFINED_ELEMENT;
}
// Handle [] on String objects.
if (this->IsStringObjectWithCharacterAt(index)) {
return STRING_CHARACTER_ELEMENT;
}
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS: {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>
(Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedArray::cast(elements())->length());
if ((index < length) &&
!FixedArray::cast(elements())->get(index)->IsTheHole()) {
return FAST_ELEMENT;
}
break;
}
case FAST_DOUBLE_ELEMENTS: {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>
(Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedDoubleArray::cast(elements())->length());
if ((index < length) &&
!FixedDoubleArray::cast(elements())->is_the_hole(index)) {
return FAST_ELEMENT;
}
break;
}
case EXTERNAL_PIXEL_ELEMENTS: {
ExternalPixelArray* pixels = ExternalPixelArray::cast(elements());
if (index < static_cast<uint32_t>(pixels->length())) return FAST_ELEMENT;
break;
}
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS: {
ExternalArray* array = ExternalArray::cast(elements());
if (index < static_cast<uint32_t>(array->length())) return FAST_ELEMENT;
break;
}
case DICTIONARY_ELEMENTS: {
if (element_dictionary()->FindEntry(index) !=
SeededNumberDictionary::kNotFound) {
return DICTIONARY_ELEMENT;
}
break;
}
case NON_STRICT_ARGUMENTS_ELEMENTS: {
// Aliased parameters and non-aliased elements in a fast backing store
// behave as FAST_ELEMENT. Non-aliased elements in a dictionary
// backing store behave as DICTIONARY_ELEMENT.
FixedArray* parameter_map = FixedArray::cast(elements());
uint32_t length = parameter_map->length();
Object* probe =
index < (length - 2) ? parameter_map->get(index + 2) : NULL;
if (probe != NULL && !probe->IsTheHole()) return FAST_ELEMENT;
// If not aliased, check the arguments.
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(arguments);
if (dictionary->FindEntry(index) != SeededNumberDictionary::kNotFound) {
return DICTIONARY_ELEMENT;
}
} else {
length = arguments->length();
probe = (index < length) ? arguments->get(index) : NULL;
if (probe != NULL && !probe->IsTheHole()) return FAST_ELEMENT;
}
break;
}
}
return UNDEFINED_ELEMENT;
}
bool JSObject::HasElementWithReceiver(JSReceiver* receiver, uint32_t index) {
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
Heap* heap = GetHeap();
if (!heap->isolate()->MayIndexedAccess(this, index, v8::ACCESS_HAS)) {
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return false;
}
}
// Check for lookup interceptor
if (HasIndexedInterceptor()) {
return HasElementWithInterceptor(receiver, index);
}
ElementsAccessor* accessor = GetElementsAccessor();
if (accessor->HasElement(receiver, this, index)) {
return true;
}
// Handle [] on String objects.
if (this->IsStringObjectWithCharacterAt(index)) return true;
Object* pt = GetPrototype();
if (pt->IsNull()) return false;
if (pt->IsJSProxy()) {
// We need to follow the spec and simulate a call to [[GetOwnProperty]].
return JSProxy::cast(pt)->GetElementAttributeWithHandler(
receiver, index) != ABSENT;
}
return JSObject::cast(pt)->HasElementWithReceiver(receiver, index);
}
MaybeObject* JSObject::SetElementWithInterceptor(uint32_t index,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
Isolate* isolate = GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetIndexedInterceptor());
Handle<JSObject> this_handle(this);
Handle<Object> value_handle(value, isolate);
if (!interceptor->setter()->IsUndefined()) {
v8::IndexedPropertySetter setter =
v8::ToCData<v8::IndexedPropertySetter>(interceptor->setter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-set", this, index));
CustomArguments args(isolate, interceptor->data(), this, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = setter(index, v8::Utils::ToLocal(value_handle), info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) return *value_handle;
}
MaybeObject* raw_result =
this_handle->SetElementWithoutInterceptor(index,
*value_handle,
attributes,
strict_mode,
check_prototype,
set_mode);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return raw_result;
}
MaybeObject* JSObject::GetElementWithCallback(Object* receiver,
Object* structure,
uint32_t index,
Object* holder) {
Isolate* isolate = GetIsolate();
ASSERT(!structure->IsForeign());
// api style callbacks.
if (structure->IsAccessorInfo()) {
Handle<AccessorInfo> data(AccessorInfo::cast(structure));
Object* fun_obj = data->getter();
v8::AccessorGetter call_fun = v8::ToCData<v8::AccessorGetter>(fun_obj);
HandleScope scope(isolate);
Handle<JSObject> self(JSObject::cast(receiver));
Handle<JSObject> holder_handle(JSObject::cast(holder));
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> key = isolate->factory()->NumberToString(number);
LOG(isolate, ApiNamedPropertyAccess("load", *self, *key));
CustomArguments args(isolate, data->data(), *self, *holder_handle);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = call_fun(v8::Utils::ToLocal(key), info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (result.IsEmpty()) return isolate->heap()->undefined_value();
return *v8::Utils::OpenHandle(*result);
}
// __defineGetter__ callback
if (structure->IsAccessorPair()) {
Object* getter = AccessorPair::cast(structure)->getter();
if (getter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return GetPropertyWithDefinedGetter(receiver, JSReceiver::cast(getter));
}
// Getter is not a function.
return isolate->heap()->undefined_value();
}
UNREACHABLE();
return NULL;
}
MaybeObject* JSObject::SetElementWithCallback(Object* structure,
uint32_t index,
Object* value,
JSObject* holder,
StrictModeFlag strict_mode) {
Isolate* isolate = GetIsolate();
HandleScope scope(isolate);
// We should never get here to initialize a const with the hole
// value since a const declaration would conflict with the setter.
ASSERT(!value->IsTheHole());
Handle<Object> value_handle(value, isolate);
// To accommodate both the old and the new api we switch on the
// data structure used to store the callbacks. Eventually foreign
// callbacks should be phased out.
ASSERT(!structure->IsForeign());
if (structure->IsAccessorInfo()) {
// api style callbacks
Handle<JSObject> self(this);
Handle<JSObject> holder_handle(JSObject::cast(holder));
Handle<AccessorInfo> data(AccessorInfo::cast(structure));
Object* call_obj = data->setter();
v8::AccessorSetter call_fun = v8::ToCData<v8::AccessorSetter>(call_obj);
if (call_fun == NULL) return value;
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> key(isolate->factory()->NumberToString(number));
LOG(isolate, ApiNamedPropertyAccess("store", *self, *key));
CustomArguments args(isolate, data->data(), *self, *holder_handle);
v8::AccessorInfo info(args.end());
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
call_fun(v8::Utils::ToLocal(key),
v8::Utils::ToLocal(value_handle),
info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return *value_handle;
}
if (structure->IsAccessorPair()) {
Handle<Object> setter(AccessorPair::cast(structure)->setter());
if (setter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return SetPropertyWithDefinedSetter(JSReceiver::cast(*setter), value);
} else {
if (strict_mode == kNonStrictMode) {
return value;
}
Handle<Object> holder_handle(holder, isolate);
Handle<Object> key(isolate->factory()->NewNumberFromUint(index));
Handle<Object> args[2] = { key, holder_handle };
return isolate->Throw(
*isolate->factory()->NewTypeError("no_setter_in_callback",
HandleVector(args, 2)));
}
}
UNREACHABLE();
return NULL;
}
bool JSObject::HasFastArgumentsElements() {
Heap* heap = GetHeap();
if (!elements()->IsFixedArray()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
if (elements->map() != heap->non_strict_arguments_elements_map()) {
return false;
}
FixedArray* arguments = FixedArray::cast(elements->get(1));
return !arguments->IsDictionary();
}
bool JSObject::HasDictionaryArgumentsElements() {
Heap* heap = GetHeap();
if (!elements()->IsFixedArray()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
if (elements->map() != heap->non_strict_arguments_elements_map()) {
return false;
}
FixedArray* arguments = FixedArray::cast(elements->get(1));
return arguments->IsDictionary();
}
// Adding n elements in fast case is O(n*n).
// Note: revisit design to have dual undefined values to capture absent
// elements.
MaybeObject* JSObject::SetFastElement(uint32_t index,
Object* value,
StrictModeFlag strict_mode,
bool check_prototype) {
ASSERT(HasFastTypeElements() ||
HasFastArgumentsElements());
FixedArray* backing_store = FixedArray::cast(elements());
if (backing_store->map() == GetHeap()->non_strict_arguments_elements_map()) {
backing_store = FixedArray::cast(backing_store->get(1));
} else {
MaybeObject* maybe = EnsureWritableFastElements();
if (!maybe->To(&backing_store)) return maybe;
}
uint32_t capacity = static_cast<uint32_t>(backing_store->length());
if (check_prototype &&
(index >= capacity || backing_store->get(index)->IsTheHole())) {
bool found;
MaybeObject* result = SetElementWithCallbackSetterInPrototypes(index,
value,
&found,
strict_mode);
if (found) return result;
}
uint32_t new_capacity = capacity;
// Check if the length property of this object needs to be updated.
uint32_t array_length = 0;
bool must_update_array_length = false;
if (IsJSArray()) {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&array_length));
if (index >= array_length) {
must_update_array_length = true;
array_length = index + 1;
}
}
// Check if the capacity of the backing store needs to be increased, or if
// a transition to slow elements is necessary.
if (index >= capacity) {
bool convert_to_slow = true;
if ((index - capacity) < kMaxGap) {
new_capacity = NewElementsCapacity(index + 1);
ASSERT(new_capacity > index);
if (!ShouldConvertToSlowElements(new_capacity)) {
convert_to_slow = false;
}
}
if (convert_to_slow) {
MaybeObject* result = NormalizeElements();
if (result->IsFailure()) return result;
return SetDictionaryElement(index, value, NONE, strict_mode,
check_prototype);
}
}
// Convert to fast double elements if appropriate.
if (HasFastSmiOnlyElements() && !value->IsSmi() && value->IsNumber()) {
MaybeObject* maybe =
SetFastDoubleElementsCapacityAndLength(new_capacity, array_length);
if (maybe->IsFailure()) return maybe;
FixedDoubleArray::cast(elements())->set(index, value->Number());
return value;
}
// Change elements kind from SMI_ONLY to generic FAST if necessary.
if (HasFastSmiOnlyElements() && !value->IsSmi()) {
Map* new_map;
{ MaybeObject* maybe_new_map = GetElementsTransitionMap(GetIsolate(),
FAST_ELEMENTS);
if (!maybe_new_map->To(&new_map)) return maybe_new_map;
}
set_map(new_map);
if (FLAG_trace_elements_transitions) {
PrintElementsTransition(stdout, FAST_SMI_ONLY_ELEMENTS, elements(),
FAST_ELEMENTS, elements());
}
}
// Increase backing store capacity if that's been decided previously.
if (new_capacity != capacity) {
FixedArray* new_elements;
SetFastElementsCapacityMode set_capacity_mode =
value->IsSmi() && HasFastSmiOnlyElements()
? kAllowSmiOnlyElements
: kDontAllowSmiOnlyElements;
{ MaybeObject* maybe =
SetFastElementsCapacityAndLength(new_capacity,
array_length,
set_capacity_mode);
if (!maybe->To(&new_elements)) return maybe;
}
new_elements->set(index, value);
return value;
}
// Finally, set the new element and length.
ASSERT(elements()->IsFixedArray());
backing_store->set(index, value);
if (must_update_array_length) {
JSArray::cast(this)->set_length(Smi::FromInt(array_length));
}
return value;
}
MaybeObject* JSObject::SetDictionaryElement(uint32_t index,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
ASSERT(HasDictionaryElements() || HasDictionaryArgumentsElements());
Isolate* isolate = GetIsolate();
Heap* heap = isolate->heap();
// Insert element in the dictionary.
FixedArray* elements = FixedArray::cast(this->elements());
bool is_arguments =
(elements->map() == heap->non_strict_arguments_elements_map());
SeededNumberDictionary* dictionary = NULL;
if (is_arguments) {
dictionary = SeededNumberDictionary::cast(elements->get(1));
} else {
dictionary = SeededNumberDictionary::cast(elements);
}
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Object* element = dictionary->ValueAt(entry);
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS && set_mode == SET_PROPERTY) {
return SetElementWithCallback(element, index, value, this, strict_mode);
} else {
dictionary->UpdateMaxNumberKey(index);
// If a value has not been initialized we allow writing to it even if it
// is read-only (a declared const that has not been initialized). If a
// value is being defined we skip attribute checks completely.
if (set_mode == DEFINE_PROPERTY) {
details = PropertyDetails(attributes, NORMAL, details.index());
dictionary->DetailsAtPut(entry, details);
} else if (details.IsReadOnly() && !element->IsTheHole()) {
if (strict_mode == kNonStrictMode) {
return isolate->heap()->undefined_value();
} else {
Handle<Object> holder(this);
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<Object> args[2] = { number, holder };
Handle<Object> error =
isolate->factory()->NewTypeError("strict_read_only_property",
HandleVector(args, 2));
return isolate->Throw(*error);
}
}
// Elements of the arguments object in slow mode might be slow aliases.
if (is_arguments && element->IsAliasedArgumentsEntry()) {
AliasedArgumentsEntry* entry = AliasedArgumentsEntry::cast(element);
Context* context = Context::cast(elements->get(0));
int context_index = entry->aliased_context_slot();
ASSERT(!context->get(context_index)->IsTheHole());
context->set(context_index, value);
// For elements that are still writable we keep slow aliasing.
if (!details.IsReadOnly()) value = element;
}
dictionary->ValueAtPut(entry, value);
}
} else {
// Index not already used. Look for an accessor in the prototype chain.
if (check_prototype) {
bool found;
MaybeObject* result =
SetElementWithCallbackSetterInPrototypes(
index, value, &found, strict_mode);
if (found) return result;
}
// When we set the is_extensible flag to false we always force the
// element into dictionary mode (and force them to stay there).
if (!map()->is_extensible()) {
if (strict_mode == kNonStrictMode) {
return isolate->heap()->undefined_value();
} else {
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> name = isolate->factory()->NumberToString(number);
Handle<Object> args[1] = { name };
Handle<Object> error =
isolate->factory()->NewTypeError("object_not_extensible",
HandleVector(args, 1));
return isolate->Throw(*error);
}
}
FixedArrayBase* new_dictionary;
PropertyDetails details = PropertyDetails(attributes, NORMAL);
MaybeObject* maybe = dictionary->AddNumberEntry(index, value, details);
if (!maybe->To(&new_dictionary)) return maybe;
if (dictionary != SeededNumberDictionary::cast(new_dictionary)) {
if (is_arguments) {
elements->set(1, new_dictionary);
} else {
set_elements(new_dictionary);
}
dictionary = SeededNumberDictionary::cast(new_dictionary);
}
}
// Update the array length if this JSObject is an array.
if (IsJSArray()) {
MaybeObject* result =
JSArray::cast(this)->JSArrayUpdateLengthFromIndex(index, value);
if (result->IsFailure()) return result;
}
// Attempt to put this object back in fast case.
if (ShouldConvertToFastElements()) {
uint32_t new_length = 0;
if (IsJSArray()) {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&new_length));
} else {
new_length = dictionary->max_number_key() + 1;
}
SetFastElementsCapacityMode set_capacity_mode = FLAG_smi_only_arrays
? kAllowSmiOnlyElements
: kDontAllowSmiOnlyElements;
bool has_smi_only_elements = false;
bool should_convert_to_fast_double_elements =
ShouldConvertToFastDoubleElements(&has_smi_only_elements);
if (has_smi_only_elements) {
set_capacity_mode = kForceSmiOnlyElements;
}
MaybeObject* result = should_convert_to_fast_double_elements
? SetFastDoubleElementsCapacityAndLength(new_length, new_length)
: SetFastElementsCapacityAndLength(new_length,
new_length,
set_capacity_mode);
if (result->IsFailure()) return result;
#ifdef DEBUG
if (FLAG_trace_normalization) {
PrintF("Object elements are fast case again:\n");
Print();
}
#endif
}
return value;
}
MUST_USE_RESULT MaybeObject* JSObject::SetFastDoubleElement(
uint32_t index,
Object* value,
StrictModeFlag strict_mode,
bool check_prototype) {
ASSERT(HasFastDoubleElements());
FixedArrayBase* base_elms = FixedArrayBase::cast(elements());
uint32_t elms_length = static_cast<uint32_t>(base_elms->length());
// If storing to an element that isn't in the array, pass the store request
// up the prototype chain before storing in the receiver's elements.
if (check_prototype &&
(index >= elms_length ||
FixedDoubleArray::cast(base_elms)->is_the_hole(index))) {
bool found;
MaybeObject* result = SetElementWithCallbackSetterInPrototypes(index,
value,
&found,
strict_mode);
if (found) return result;
}
// If the value object is not a heap number, switch to fast elements and try
// again.
bool value_is_smi = value->IsSmi();
if (!value->IsNumber()) {
Object* obj;
uint32_t length = elms_length;
if (IsJSArray()) {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&length));
}
MaybeObject* maybe_obj = SetFastElementsCapacityAndLength(
elms_length,
length,
kDontAllowSmiOnlyElements);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
return SetFastElement(index,
value,
strict_mode,
check_prototype);
}
double double_value = value_is_smi
? static_cast<double>(Smi::cast(value)->value())
: HeapNumber::cast(value)->value();
// Check whether there is extra space in the fixed array.
if (index < elms_length) {
FixedDoubleArray* elms = FixedDoubleArray::cast(elements());
elms->set(index, double_value);
if (IsJSArray()) {
// Update the length of the array if needed.
uint32_t array_length = 0;
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&array_length));
if (index >= array_length) {
JSArray::cast(this)->set_length(Smi::FromInt(index + 1));
}
}
return value;
}
// Allow gap in fast case.
if ((index - elms_length) < kMaxGap) {
// Try allocating extra space.
int new_capacity = NewElementsCapacity(index+1);
if (!ShouldConvertToSlowElements(new_capacity)) {
ASSERT(static_cast<uint32_t>(new_capacity) > index);
Object* obj;
{ MaybeObject* maybe_obj =
SetFastDoubleElementsCapacityAndLength(new_capacity,
index + 1);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedDoubleArray::cast(elements())->set(index, double_value);
return value;
}
}
// Otherwise default to slow case.
ASSERT(HasFastDoubleElements());
ASSERT(map()->has_fast_double_elements());
ASSERT(elements()->IsFixedDoubleArray());
Object* obj;
{ MaybeObject* maybe_obj = NormalizeElements();
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
ASSERT(HasDictionaryElements());
return SetElement(index, value, NONE, strict_mode, check_prototype);
}
MaybeObject* JSReceiver::SetElement(uint32_t index,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode,
bool check_proto) {
if (IsJSProxy()) {
return JSProxy::cast(this)->SetElementWithHandler(
index, value, strict_mode);
} else {
return JSObject::cast(this)->SetElement(
index, value, attributes, strict_mode, check_proto);
}
}
Handle<Object> JSObject::SetOwnElement(Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
StrictModeFlag strict_mode) {
ASSERT(!object->HasExternalArrayElements());
CALL_HEAP_FUNCTION(
object->GetIsolate(),
object->SetElement(index, *value, NONE, strict_mode, false),
Object);
}
Handle<Object> JSObject::SetElement(Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attr,
StrictModeFlag strict_mode,
SetPropertyMode set_mode) {
if (object->HasExternalArrayElements()) {
if (!value->IsSmi() && !value->IsHeapNumber() && !value->IsUndefined()) {
bool has_exception;
Handle<Object> number = Execution::ToNumber(value, &has_exception);
if (has_exception) return Handle<Object>();
value = number;
}
}
CALL_HEAP_FUNCTION(
object->GetIsolate(),
object->SetElement(index, *value, attr, strict_mode, true, set_mode),
Object);
}
MaybeObject* JSObject::SetElement(uint32_t index,
Object* value,
PropertyAttributes attributes,
StrictModeFlag strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
Heap* heap = GetHeap();
if (!heap->isolate()->MayIndexedAccess(this, index, v8::ACCESS_SET)) {
HandleScope scope(heap->isolate());
Handle<Object> value_handle(value);
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_SET);
return *value_handle;
}
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return value;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->SetElement(index,
value,
attributes,
strict_mode,
check_prototype,
set_mode);
}
// Don't allow element properties to be redefined for external arrays.
if (HasExternalArrayElements() && set_mode == DEFINE_PROPERTY) {
Isolate* isolate = GetHeap()->isolate();
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<Object> args[] = { Handle<Object>(this), number };
Handle<Object> error = isolate->factory()->NewTypeError(
"redef_external_array_element", HandleVector(args, ARRAY_SIZE(args)));
return isolate->Throw(*error);
}
// Normalize the elements to enable attributes on the property.
if ((attributes & (DONT_DELETE | DONT_ENUM | READ_ONLY)) != 0) {
SeededNumberDictionary* dictionary;
MaybeObject* maybe_object = NormalizeElements();
if (!maybe_object->To(&dictionary)) return maybe_object;
// Make sure that we never go back to fast case.
dictionary->set_requires_slow_elements();
}
// Check for lookup interceptor
if (HasIndexedInterceptor()) {
return SetElementWithInterceptor(index,
value,
attributes,
strict_mode,
check_prototype,
set_mode);
}
return SetElementWithoutInterceptor(index,
value,
attributes,
strict_mode,
check_prototype,
set_mode);
}
MaybeObject* JSObject::SetElementWithoutInterceptor(uint32_t index,
Object* value,
PropertyAttributes attr,
StrictModeFlag strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
ASSERT(HasDictionaryElements() ||
HasDictionaryArgumentsElements() ||
(attr & (DONT_DELETE | DONT_ENUM | READ_ONLY)) == 0);
Isolate* isolate = GetIsolate();
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS:
return SetFastElement(index, value, strict_mode, check_prototype);
case FAST_DOUBLE_ELEMENTS:
return SetFastDoubleElement(index, value, strict_mode, check_prototype);
case EXTERNAL_PIXEL_ELEMENTS: {
ExternalPixelArray* pixels = ExternalPixelArray::cast(elements());
return pixels->SetValue(index, value);
}
case EXTERNAL_BYTE_ELEMENTS: {
ExternalByteArray* array = ExternalByteArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS: {
ExternalUnsignedByteArray* array =
ExternalUnsignedByteArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_SHORT_ELEMENTS: {
ExternalShortArray* array = ExternalShortArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS: {
ExternalUnsignedShortArray* array =
ExternalUnsignedShortArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_INT_ELEMENTS: {
ExternalIntArray* array = ExternalIntArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_UNSIGNED_INT_ELEMENTS: {
ExternalUnsignedIntArray* array =
ExternalUnsignedIntArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_FLOAT_ELEMENTS: {
ExternalFloatArray* array = ExternalFloatArray::cast(elements());
return array->SetValue(index, value);
}
case EXTERNAL_DOUBLE_ELEMENTS: {
ExternalDoubleArray* array = ExternalDoubleArray::cast(elements());
return array->SetValue(index, value);
}
case DICTIONARY_ELEMENTS:
return SetDictionaryElement(index, value, attr, strict_mode,
check_prototype, set_mode);
case NON_STRICT_ARGUMENTS_ELEMENTS: {
FixedArray* parameter_map = FixedArray::cast(elements());
uint32_t length = parameter_map->length();
Object* probe =
(index < length - 2) ? parameter_map->get(index + 2) : NULL;
if (probe != NULL && !probe->IsTheHole()) {
Context* context = Context::cast(parameter_map->get(0));
int context_index = Smi::cast(probe)->value();
ASSERT(!context->get(context_index)->IsTheHole());
context->set(context_index, value);
// Redefining attributes of an aliased element destroys fast aliasing.
if (set_mode == SET_PROPERTY || attr == NONE) return value;
parameter_map->set_the_hole(index + 2);
// For elements that are still writable we re-establish slow aliasing.
if ((attr & READ_ONLY) == 0) {
MaybeObject* maybe_entry =
isolate->heap()->AllocateAliasedArgumentsEntry(context_index);
if (!maybe_entry->ToObject(&value)) return maybe_entry;
}
}
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
return SetDictionaryElement(index, value, attr, strict_mode,
check_prototype, set_mode);
} else {
return SetFastElement(index, value, strict_mode, check_prototype);
}
}
}
// All possible cases have been handled above. Add a return to avoid the
// complaints from the compiler.
UNREACHABLE();
return isolate->heap()->null_value();
}
Handle<Object> JSObject::TransitionElementsKind(Handle<JSObject> object,
ElementsKind to_kind) {
CALL_HEAP_FUNCTION(object->GetIsolate(),
object->TransitionElementsKind(to_kind),
Object);
}
MaybeObject* JSObject::TransitionElementsKind(ElementsKind to_kind) {
ElementsKind from_kind = map()->elements_kind();
Isolate* isolate = GetIsolate();
if ((from_kind == FAST_SMI_ONLY_ELEMENTS ||
elements() == isolate->heap()->empty_fixed_array()) &&
to_kind == FAST_ELEMENTS) {
ASSERT(from_kind != FAST_ELEMENTS);
MaybeObject* maybe_new_map = GetElementsTransitionMap(isolate, to_kind);
Map* new_map;
if (!maybe_new_map->To(&new_map)) return maybe_new_map;
set_map(new_map);
if (FLAG_trace_elements_transitions) {
FixedArrayBase* elms = FixedArrayBase::cast(elements());
PrintElementsTransition(stdout, from_kind, elms, to_kind, elms);
}
return this;
}
FixedArrayBase* elms = FixedArrayBase::cast(elements());
uint32_t capacity = static_cast<uint32_t>(elms->length());
uint32_t length = capacity;
if (IsJSArray()) {
Object* raw_length = JSArray::cast(this)->length();
if (raw_length->IsUndefined()) {
// If length is undefined, then JSArray is being initialized and has no
// elements, assume a length of zero.
length = 0;
} else {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&length));
}
}
if (from_kind == FAST_SMI_ONLY_ELEMENTS &&
to_kind == FAST_DOUBLE_ELEMENTS) {
MaybeObject* maybe_result =
SetFastDoubleElementsCapacityAndLength(capacity, length);
if (maybe_result->IsFailure()) return maybe_result;
return this;
}
if (from_kind == FAST_DOUBLE_ELEMENTS && to_kind == FAST_ELEMENTS) {
MaybeObject* maybe_result = SetFastElementsCapacityAndLength(
capacity, length, kDontAllowSmiOnlyElements);
if (maybe_result->IsFailure()) return maybe_result;
return this;
}
// This method should never be called for any other case than the ones
// handled above.
UNREACHABLE();
return GetIsolate()->heap()->null_value();
}
// static
bool Map::IsValidElementsTransition(ElementsKind from_kind,
ElementsKind to_kind) {
return
(from_kind == FAST_SMI_ONLY_ELEMENTS &&
(to_kind == FAST_DOUBLE_ELEMENTS || to_kind == FAST_ELEMENTS)) ||
(from_kind == FAST_DOUBLE_ELEMENTS && to_kind == FAST_ELEMENTS);
}
MaybeObject* JSArray::JSArrayUpdateLengthFromIndex(uint32_t index,
Object* value) {
uint32_t old_len = 0;
CHECK(length()->ToArrayIndex(&old_len));
// Check to see if we need to update the length. For now, we make
// sure that the length stays within 32-bits (unsigned).
if (index >= old_len && index != 0xffffffff) {
Object* len;
{ MaybeObject* maybe_len =
GetHeap()->NumberFromDouble(static_cast<double>(index) + 1);
if (!maybe_len->ToObject(&len)) return maybe_len;
}
set_length(len);
}
return value;
}
MaybeObject* JSObject::GetElementWithInterceptor(Object* receiver,
uint32_t index) {
Isolate* isolate = GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc;
HandleScope scope(isolate);
Handle<InterceptorInfo> interceptor(GetIndexedInterceptor(), isolate);
Handle<Object> this_handle(receiver, isolate);
Handle<JSObject> holder_handle(this, isolate);
if (!interceptor->getter()->IsUndefined()) {
v8::IndexedPropertyGetter getter =
v8::ToCData<v8::IndexedPropertyGetter>(interceptor->getter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-get", this, index));
CustomArguments args(isolate, interceptor->data(), receiver, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = getter(index, info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) return *v8::Utils::OpenHandle(*result);
}
Heap* heap = holder_handle->GetHeap();
ElementsAccessor* handler = holder_handle->GetElementsAccessor();
MaybeObject* raw_result = handler->Get(*this_handle,
*holder_handle,
index);
if (raw_result != heap->the_hole_value()) return raw_result;
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
Object* pt = holder_handle->GetPrototype();
if (pt == heap->null_value()) return heap->undefined_value();
return pt->GetElementWithReceiver(*this_handle, index);
}
bool JSObject::HasDenseElements() {
int capacity = 0;
int used = 0;
GetElementsCapacityAndUsage(&capacity, &used);
return (capacity == 0) || (used > (capacity / 2));
}
void JSObject::GetElementsCapacityAndUsage(int* capacity, int* used) {
*capacity = 0;
*used = 0;
FixedArrayBase* backing_store_base = FixedArrayBase::cast(elements());
FixedArray* backing_store = NULL;
switch (GetElementsKind()) {
case NON_STRICT_ARGUMENTS_ELEMENTS:
backing_store_base =
FixedArray::cast(FixedArray::cast(backing_store_base)->get(1));
backing_store = FixedArray::cast(backing_store_base);
if (backing_store->IsDictionary()) {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(backing_store);
*capacity = dictionary->Capacity();
*used = dictionary->NumberOfElements();
break;
}
// Fall through.
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS:
backing_store = FixedArray::cast(backing_store_base);
*capacity = backing_store->length();
for (int i = 0; i < *capacity; ++i) {
if (!backing_store->get(i)->IsTheHole()) ++(*used);
}
break;
case DICTIONARY_ELEMENTS: {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(FixedArray::cast(elements()));
*capacity = dictionary->Capacity();
*used = dictionary->NumberOfElements();
break;
}
case FAST_DOUBLE_ELEMENTS: {
FixedDoubleArray* elms = FixedDoubleArray::cast(elements());
*capacity = elms->length();
for (int i = 0; i < *capacity; i++) {
if (!elms->is_the_hole(i)) ++(*used);
}
break;
}
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS:
case EXTERNAL_PIXEL_ELEMENTS:
// External arrays are considered 100% used.
ExternalArray* external_array = ExternalArray::cast(elements());
*capacity = external_array->length();
*used = external_array->length();
break;
}
}
bool JSObject::ShouldConvertToSlowElements(int new_capacity) {
STATIC_ASSERT(kMaxUncheckedOldFastElementsLength <=
kMaxUncheckedFastElementsLength);
if (new_capacity <= kMaxUncheckedOldFastElementsLength ||
(new_capacity <= kMaxUncheckedFastElementsLength &&
GetHeap()->InNewSpace(this))) {
return false;
}
// If the fast-case backing storage takes up roughly three times as
// much space (in machine words) as a dictionary backing storage
// would, the object should have slow elements.
int old_capacity = 0;
int used_elements = 0;
GetElementsCapacityAndUsage(&old_capacity, &used_elements);
int dictionary_size = SeededNumberDictionary::ComputeCapacity(used_elements) *
SeededNumberDictionary::kEntrySize;
return 3 * dictionary_size <= new_capacity;
}
bool JSObject::ShouldConvertToFastElements() {
ASSERT(HasDictionaryElements() || HasDictionaryArgumentsElements());
// If the elements are sparse, we should not go back to fast case.
if (!HasDenseElements()) return false;
// An object requiring access checks is never allowed to have fast
// elements. If it had fast elements we would skip security checks.
if (IsAccessCheckNeeded()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
SeededNumberDictionary* dictionary = NULL;
if (elements->map() == GetHeap()->non_strict_arguments_elements_map()) {
dictionary = SeededNumberDictionary::cast(elements->get(1));
} else {
dictionary = SeededNumberDictionary::cast(elements);
}
// If an element has been added at a very high index in the elements
// dictionary, we cannot go back to fast case.
if (dictionary->requires_slow_elements()) return false;
// If the dictionary backing storage takes up roughly half as much
// space (in machine words) as a fast-case backing storage would,
// the object should have fast elements.
uint32_t array_size = 0;
if (IsJSArray()) {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&array_size));
} else {
array_size = dictionary->max_number_key();
}
uint32_t dictionary_size = static_cast<uint32_t>(dictionary->Capacity()) *
SeededNumberDictionary::kEntrySize;
return 2 * dictionary_size >= array_size;
}
bool JSObject::ShouldConvertToFastDoubleElements(
bool* has_smi_only_elements) {
*has_smi_only_elements = false;
if (FLAG_unbox_double_arrays) {
ASSERT(HasDictionaryElements());
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(elements());
bool found_double = false;
for (int i = 0; i < dictionary->Capacity(); i++) {
Object* key = dictionary->KeyAt(i);
if (key->IsNumber()) {
Object* value = dictionary->ValueAt(i);
if (!value->IsNumber()) return false;
if (!value->IsSmi()) {
found_double = true;
}
}
}
*has_smi_only_elements = !found_double;
return found_double;
} else {
return false;
}
}
// Certain compilers request function template instantiation when they
// see the definition of the other template functions in the
// class. This requires us to have the template functions put
// together, so even though this function belongs in objects-debug.cc,
// we keep it here instead to satisfy certain compilers.
#ifdef OBJECT_PRINT
template<typename Shape, typename Key>
void Dictionary<Shape, Key>::Print(FILE* out) {
int capacity = HashTable<Shape, Key>::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = HashTable<Shape, Key>::KeyAt(i);
if (HashTable<Shape, Key>::IsKey(k)) {
PrintF(out, " ");
if (k->IsString()) {
String::cast(k)->StringPrint(out);
} else {
k->ShortPrint(out);
}
PrintF(out, ": ");
ValueAt(i)->ShortPrint(out);
PrintF(out, "\n");
}
}
}
#endif
template<typename Shape, typename Key>
void Dictionary<Shape, Key>::CopyValuesTo(FixedArray* elements) {
int pos = 0;
int capacity = HashTable<Shape, Key>::Capacity();
AssertNoAllocation no_gc;
WriteBarrierMode mode = elements->GetWriteBarrierMode(no_gc);
for (int i = 0; i < capacity; i++) {
Object* k = Dictionary<Shape, Key>::KeyAt(i);
if (Dictionary<Shape, Key>::IsKey(k)) {
elements->set(pos++, ValueAt(i), mode);
}
}
ASSERT(pos == elements->length());
}
InterceptorInfo* JSObject::GetNamedInterceptor() {
ASSERT(map()->has_named_interceptor());
JSFunction* constructor = JSFunction::cast(map()->constructor());
ASSERT(constructor->shared()->IsApiFunction());
Object* result =
constructor->shared()->get_api_func_data()->named_property_handler();
return InterceptorInfo::cast(result);
}
InterceptorInfo* JSObject::GetIndexedInterceptor() {
ASSERT(map()->has_indexed_interceptor());
JSFunction* constructor = JSFunction::cast(map()->constructor());
ASSERT(constructor->shared()->IsApiFunction());
Object* result =
constructor->shared()->get_api_func_data()->indexed_property_handler();
return InterceptorInfo::cast(result);
}
MaybeObject* JSObject::GetPropertyPostInterceptor(
JSReceiver* receiver,
String* name,
PropertyAttributes* attributes) {
// Check local property in holder, ignore interceptor.
LookupResult result(GetIsolate());
LocalLookupRealNamedProperty(name, &result);
if (result.IsProperty()) {
return GetProperty(receiver, &result, name, attributes);
}
// Continue searching via the prototype chain.
Object* pt = GetPrototype();
*attributes = ABSENT;
if (pt->IsNull()) return GetHeap()->undefined_value();
return pt->GetPropertyWithReceiver(receiver, name, attributes);
}
MaybeObject* JSObject::GetLocalPropertyPostInterceptor(
JSReceiver* receiver,
String* name,
PropertyAttributes* attributes) {
// Check local property in holder, ignore interceptor.
LookupResult result(GetIsolate());
LocalLookupRealNamedProperty(name, &result);
if (result.IsProperty()) {
return GetProperty(receiver, &result, name, attributes);
}
return GetHeap()->undefined_value();
}
MaybeObject* JSObject::GetPropertyWithInterceptor(
JSReceiver* receiver,
String* name,
PropertyAttributes* attributes) {
Isolate* isolate = GetIsolate();
InterceptorInfo* interceptor = GetNamedInterceptor();
HandleScope scope(isolate);
Handle<JSReceiver> receiver_handle(receiver);
Handle<JSObject> holder_handle(this);
Handle<String> name_handle(name);
if (!interceptor->getter()->IsUndefined()) {
v8::NamedPropertyGetter getter =
v8::ToCData<v8::NamedPropertyGetter>(interceptor->getter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-get", *holder_handle, name));
CustomArguments args(isolate, interceptor->data(), receiver, this);
v8::AccessorInfo info(args.end());
v8::Handle<v8::Value> result;
{
// Leaving JavaScript.
VMState state(isolate, EXTERNAL);
result = getter(v8::Utils::ToLocal(name_handle), info);
}
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.IsEmpty()) {
*attributes = NONE;
return *v8::Utils::OpenHandle(*result);
}
}
MaybeObject* result = holder_handle->GetPropertyPostInterceptor(
*receiver_handle,
*name_handle,
attributes);
RETURN_IF_SCHEDULED_EXCEPTION(isolate);
return result;
}
bool JSObject::HasRealNamedProperty(String* key) {
// Check access rights if needed.
Isolate* isolate = GetIsolate();
if (IsAccessCheckNeeded()) {
if (!isolate->MayNamedAccess(this, key, v8::ACCESS_HAS)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return false;
}
}
LookupResult result(isolate);
LocalLookupRealNamedProperty(key, &result);
return result.IsProperty() && (result.type() != INTERCEPTOR);
}
bool JSObject::HasRealElementProperty(uint32_t index) {
// Check access rights if needed.
if (IsAccessCheckNeeded()) {
Heap* heap = GetHeap();
if (!heap->isolate()->MayIndexedAccess(this, index, v8::ACCESS_HAS)) {
heap->isolate()->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return false;
}
}
if (IsJSGlobalProxy()) {
Object* proto = GetPrototype();
if (proto->IsNull()) return false;
ASSERT(proto->IsJSGlobalObject());
return JSObject::cast(proto)->HasRealElementProperty(index);
}
// Handle [] on String objects.
if (this->IsStringObjectWithCharacterAt(index)) return true;
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS: {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>(
Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedArray::cast(elements())->length());
return (index < length) &&
!FixedArray::cast(elements())->get(index)->IsTheHole();
}
case FAST_DOUBLE_ELEMENTS: {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>(
Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedDoubleArray::cast(elements())->length());
return (index < length) &&
!FixedDoubleArray::cast(elements())->is_the_hole(index);
break;
}
case EXTERNAL_PIXEL_ELEMENTS: {
ExternalPixelArray* pixels = ExternalPixelArray::cast(elements());
return index < static_cast<uint32_t>(pixels->length());
}
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS: {
ExternalArray* array = ExternalArray::cast(elements());
return index < static_cast<uint32_t>(array->length());
}
case DICTIONARY_ELEMENTS: {
return element_dictionary()->FindEntry(index)
!= SeededNumberDictionary::kNotFound;
}
case NON_STRICT_ARGUMENTS_ELEMENTS:
UNIMPLEMENTED();
break;
}
// All possibilities have been handled above already.
UNREACHABLE();
return GetHeap()->null_value();
}
bool JSObject::HasRealNamedCallbackProperty(String* key) {
// Check access rights if needed.
Isolate* isolate = GetIsolate();
if (IsAccessCheckNeeded()) {
if (!isolate->MayNamedAccess(this, key, v8::ACCESS_HAS)) {
isolate->ReportFailedAccessCheck(this, v8::ACCESS_HAS);
return false;
}
}
LookupResult result(isolate);
LocalLookupRealNamedProperty(key, &result);
return result.IsFound() && (result.type() == CALLBACKS);
}
int JSObject::NumberOfLocalProperties(PropertyAttributes filter) {
return HasFastProperties() ?
map()->NumberOfDescribedProperties(filter) :
property_dictionary()->NumberOfElementsFilterAttributes(filter);
}
void FixedArray::SwapPairs(FixedArray* numbers, int i, int j) {
Object* temp = get(i);
set(i, get(j));
set(j, temp);
if (this != numbers) {
temp = numbers->get(i);
numbers->set(i, Smi::cast(numbers->get(j)));
numbers->set(j, Smi::cast(temp));
}
}
static void InsertionSortPairs(FixedArray* content,
FixedArray* numbers,
int len) {
for (int i = 1; i < len; i++) {
int j = i;
while (j > 0 &&
(NumberToUint32(numbers->get(j - 1)) >
NumberToUint32(numbers->get(j)))) {
content->SwapPairs(numbers, j - 1, j);
j--;
}
}
}
void HeapSortPairs(FixedArray* content, FixedArray* numbers, int len) {
// In-place heap sort.
ASSERT(content->length() == numbers->length());
// Bottom-up max-heap construction.
for (int i = 1; i < len; ++i) {
int child_index = i;
while (child_index > 0) {
int parent_index = ((child_index + 1) >> 1) - 1;
uint32_t parent_value = NumberToUint32(numbers->get(parent_index));
uint32_t child_value = NumberToUint32(numbers->get(child_index));
if (parent_value < child_value) {
content->SwapPairs(numbers, parent_index, child_index);
} else {
break;
}
child_index = parent_index;
}
}
// Extract elements and create sorted array.
for (int i = len - 1; i > 0; --i) {
// Put max element at the back of the array.
content->SwapPairs(numbers, 0, i);
// Sift down the new top element.
int parent_index = 0;
while (true) {
int child_index = ((parent_index + 1) << 1) - 1;
if (child_index >= i) break;
uint32_t child1_value = NumberToUint32(numbers->get(child_index));
uint32_t child2_value = NumberToUint32(numbers->get(child_index + 1));
uint32_t parent_value = NumberToUint32(numbers->get(parent_index));
if (child_index + 1 >= i || child1_value > child2_value) {
if (parent_value > child1_value) break;
content->SwapPairs(numbers, parent_index, child_index);
parent_index = child_index;
} else {
if (parent_value > child2_value) break;
content->SwapPairs(numbers, parent_index, child_index + 1);
parent_index = child_index + 1;
}
}
}
}
// Sort this array and the numbers as pairs wrt. the (distinct) numbers.
void FixedArray::SortPairs(FixedArray* numbers, uint32_t len) {
ASSERT(this->length() == numbers->length());
// For small arrays, simply use insertion sort.
if (len <= 10) {
InsertionSortPairs(this, numbers, len);
return;
}
// Check the range of indices.
uint32_t min_index = NumberToUint32(numbers->get(0));
uint32_t max_index = min_index;
uint32_t i;
for (i = 1; i < len; i++) {
if (NumberToUint32(numbers->get(i)) < min_index) {
min_index = NumberToUint32(numbers->get(i));
} else if (NumberToUint32(numbers->get(i)) > max_index) {
max_index = NumberToUint32(numbers->get(i));
}
}
if (max_index - min_index + 1 == len) {
// Indices form a contiguous range, unless there are duplicates.
// Do an in-place linear time sort assuming distinct numbers, but
// avoid hanging in case they are not.
for (i = 0; i < len; i++) {
uint32_t p;
uint32_t j = 0;
// While the current element at i is not at its correct position p,
// swap the elements at these two positions.
while ((p = NumberToUint32(numbers->get(i)) - min_index) != i &&
j++ < len) {
SwapPairs(numbers, i, p);
}
}
} else {
HeapSortPairs(this, numbers, len);
return;
}
}
// Fill in the names of local properties into the supplied storage. The main
// purpose of this function is to provide reflection information for the object
// mirrors.
void JSObject::GetLocalPropertyNames(FixedArray* storage, int index) {
ASSERT(storage->length() >= (NumberOfLocalProperties() - index));
if (HasFastProperties()) {
DescriptorArray* descs = map()->instance_descriptors();
for (int i = 0; i < descs->number_of_descriptors(); i++) {
if (descs->IsProperty(i)) storage->set(index++, descs->GetKey(i));
}
ASSERT(storage->length() >= index);
} else {
property_dictionary()->CopyKeysTo(storage,
index,
StringDictionary::UNSORTED);
}
}
int JSObject::NumberOfLocalElements(PropertyAttributes filter) {
return GetLocalElementKeys(NULL, filter);
}
int JSObject::NumberOfEnumElements() {
// Fast case for objects with no elements.
if (!IsJSValue() && HasFastElements()) {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>(
Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedArray::cast(elements())->length());
if (length == 0) return 0;
}
// Compute the number of enumerable elements.
return NumberOfLocalElements(static_cast<PropertyAttributes>(DONT_ENUM));
}
int JSObject::GetLocalElementKeys(FixedArray* storage,
PropertyAttributes filter) {
int counter = 0;
switch (GetElementsKind()) {
case FAST_SMI_ONLY_ELEMENTS:
case FAST_ELEMENTS: {
int length = IsJSArray() ?
Smi::cast(JSArray::cast(this)->length())->value() :
FixedArray::cast(elements())->length();
for (int i = 0; i < length; i++) {
if (!FixedArray::cast(elements())->get(i)->IsTheHole()) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(i));
}
counter++;
}
}
ASSERT(!storage || storage->length() >= counter);
break;
}
case FAST_DOUBLE_ELEMENTS: {
int length = IsJSArray() ?
Smi::cast(JSArray::cast(this)->length())->value() :
FixedDoubleArray::cast(elements())->length();
for (int i = 0; i < length; i++) {
if (!FixedDoubleArray::cast(elements())->is_the_hole(i)) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(i));
}
counter++;
}
}
ASSERT(!storage || storage->length() >= counter);
break;
}
case EXTERNAL_PIXEL_ELEMENTS: {
int length = ExternalPixelArray::cast(elements())->length();
while (counter < length) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(counter));
}
counter++;
}
ASSERT(!storage || storage->length() >= counter);
break;
}
case EXTERNAL_BYTE_ELEMENTS:
case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
case EXTERNAL_SHORT_ELEMENTS:
case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
case EXTERNAL_INT_ELEMENTS:
case EXTERNAL_UNSIGNED_INT_ELEMENTS:
case EXTERNAL_FLOAT_ELEMENTS:
case EXTERNAL_DOUBLE_ELEMENTS: {
int length = ExternalArray::cast(elements())->length();
while (counter < length) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(counter));
}
counter++;
}
ASSERT(!storage || storage->length() >= counter);
break;
}
case DICTIONARY_ELEMENTS: {
if (storage != NULL) {
element_dictionary()->CopyKeysTo(storage,
filter,
SeededNumberDictionary::SORTED);
}
counter += element_dictionary()->NumberOfElementsFilterAttributes(filter);
break;
}
case NON_STRICT_ARGUMENTS_ELEMENTS: {
FixedArray* parameter_map = FixedArray::cast(elements());
int mapped_length = parameter_map->length() - 2;
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
// Copy the keys from arguments first, because Dictionary::CopyKeysTo
// will insert in storage starting at index 0.
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(arguments);
if (storage != NULL) {
dictionary->CopyKeysTo(
storage, filter, SeededNumberDictionary::UNSORTED);
}
counter += dictionary->NumberOfElementsFilterAttributes(filter);
for (int i = 0; i < mapped_length; ++i) {
if (!parameter_map->get(i + 2)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
if (storage != NULL) storage->SortPairs(storage, counter);
} else {
int backing_length = arguments->length();
int i = 0;
for (; i < mapped_length; ++i) {
if (!parameter_map->get(i + 2)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
} else if (i < backing_length && !arguments->get(i)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
for (; i < backing_length; ++i) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
break;
}
}
if (this->IsJSValue()) {
Object* val = JSValue::cast(this)->value();
if (val->IsString()) {
String* str = String::cast(val);
if (storage) {
for (int i = 0; i < str->length(); i++) {
storage->set(counter + i, Smi::FromInt(i));
}
}
counter += str->length();
}
}
ASSERT(!storage || storage->length() == counter);
return counter;
}
int JSObject::GetEnumElementKeys(FixedArray* storage) {
return GetLocalElementKeys(storage,
static_cast<PropertyAttributes>(DONT_ENUM));
}
// StringKey simply carries a string object as key.
class StringKey : public HashTableKey {
public:
explicit StringKey(String* string) :
string_(string),
hash_(HashForObject(string)) { }
bool IsMatch(Object* string) {
// We know that all entries in a hash table had their hash keys created.
// Use that knowledge to have fast failure.
if (hash_ != HashForObject(string)) {
return false;
}
return string_->Equals(String::cast(string));
}
uint32_t Hash() { return hash_; }
uint32_t HashForObject(Object* other) { return String::cast(other)->Hash(); }
Object* AsObject() { return string_; }
String* string_;
uint32_t hash_;
};
// StringSharedKeys are used as keys in the eval cache.
class StringSharedKey : public HashTableKey {
public:
StringSharedKey(String* source,
SharedFunctionInfo* shared,
LanguageMode language_mode,
int scope_position)
: source_(source),
shared_(shared),
language_mode_(language_mode),
scope_position_(scope_position) { }
bool IsMatch(Object* other) {
if (!other->IsFixedArray()) return false;
FixedArray* other_array = FixedArray::cast(other);
SharedFunctionInfo* shared = SharedFunctionInfo::cast(other_array->get(0));
if (shared != shared_) return false;
int language_unchecked = Smi::cast(other_array->get(2))->value();
ASSERT(language_unchecked == CLASSIC_MODE ||
language_unchecked == STRICT_MODE ||
language_unchecked == EXTENDED_MODE);
LanguageMode language_mode = static_cast<LanguageMode>(language_unchecked);
if (language_mode != language_mode_) return false;
int scope_position = Smi::cast(other_array->get(3))->value();
if (scope_position != scope_position_) return false;
String* source = String::cast(other_array->get(1));
return source->Equals(source_);
}
static uint32_t StringSharedHashHelper(String* source,
SharedFunctionInfo* shared,
LanguageMode language_mode,
int scope_position) {
uint32_t hash = source->Hash();
if (shared->HasSourceCode()) {
// Instead of using the SharedFunctionInfo pointer in the hash
// code computation, we use a combination of the hash of the
// script source code and the start position of the calling scope.
// We do this to ensure that the cache entries can survive garbage
// collection.
Script* script = Script::cast(shared->script());
hash ^= String::cast(script->source())->Hash();
if (language_mode == STRICT_MODE) hash ^= 0x8000;
if (language_mode == EXTENDED_MODE) hash ^= 0x0080;
hash += scope_position;
}
return hash;
}
uint32_t Hash() {
return StringSharedHashHelper(
source_, shared_, language_mode_, scope_position_);
}
uint32_t HashForObject(Object* obj) {
FixedArray* other_array = FixedArray::cast(obj);
SharedFunctionInfo* shared = SharedFunctionInfo::cast(other_array->get(0));
String* source = String::cast(other_array->get(1));
int language_unchecked = Smi::cast(other_array->get(2))->value();
ASSERT(language_unchecked == CLASSIC_MODE ||
language_unchecked == STRICT_MODE ||
language_unchecked == EXTENDED_MODE);
LanguageMode language_mode = static_cast<LanguageMode>(language_unchecked);
int scope_position = Smi::cast(other_array->get(3))->value();
return StringSharedHashHelper(
source, shared, language_mode, scope_position);
}
MUST_USE_RESULT MaybeObject* AsObject() {
Object* obj;
{ MaybeObject* maybe_obj = source_->GetHeap()->AllocateFixedArray(4);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* other_array = FixedArray::cast(obj);
other_array->set(0, shared_);
other_array->set(1, source_);
other_array->set(2, Smi::FromInt(language_mode_));
other_array->set(3, Smi::FromInt(scope_position_));
return other_array;
}
private:
String* source_;
SharedFunctionInfo* shared_;
LanguageMode language_mode_;
int scope_position_;
};
// RegExpKey carries the source and flags of a regular expression as key.
class RegExpKey : public HashTableKey {
public:
RegExpKey(String* string, JSRegExp::Flags flags)
: string_(string),
flags_(Smi::FromInt(flags.value())) { }
// Rather than storing the key in the hash table, a pointer to the
// stored value is stored where the key should be. IsMatch then
// compares the search key to the found object, rather than comparing
// a key to a key.
bool IsMatch(Object* obj) {
FixedArray* val = FixedArray::cast(obj);
return string_->Equals(String::cast(val->get(JSRegExp::kSourceIndex)))
&& (flags_ == val->get(JSRegExp::kFlagsIndex));
}
uint32_t Hash() { return RegExpHash(string_, flags_); }
Object* AsObject() {
// Plain hash maps, which is where regexp keys are used, don't
// use this function.
UNREACHABLE();
return NULL;
}
uint32_t HashForObject(Object* obj) {
FixedArray* val = FixedArray::cast(obj);
return RegExpHash(String::cast(val->get(JSRegExp::kSourceIndex)),
Smi::cast(val->get(JSRegExp::kFlagsIndex)));
}
static uint32_t RegExpHash(String* string, Smi* flags) {
return string->Hash() + flags->value();
}
String* string_;
Smi* flags_;
};
// Utf8SymbolKey carries a vector of chars as key.
class Utf8SymbolKey : public HashTableKey {
public:
explicit Utf8SymbolKey(Vector<const char> string, uint32_t seed)
: string_(string), hash_field_(0), seed_(seed) { }
bool IsMatch(Object* string) {
return String::cast(string)->IsEqualTo(string_);
}
uint32_t Hash() {
if (hash_field_ != 0) return hash_field_ >> String::kHashShift;
unibrow::Utf8InputBuffer<> buffer(string_.start(),
static_cast<unsigned>(string_.length()));
chars_ = buffer.Utf16Length();
hash_field_ = String::ComputeHashField(&buffer, chars_, seed_);
uint32_t result = hash_field_ >> String::kHashShift;
ASSERT(result != 0); // Ensure that the hash value of 0 is never computed.
return result;
}
uint32_t HashForObject(Object* other) {
return String::cast(other)->Hash();
}
MaybeObject* AsObject() {
if (hash_field_ == 0) Hash();
return Isolate::Current()->heap()->AllocateSymbol(
string_, chars_, hash_field_);
}
Vector<const char> string_;
uint32_t hash_field_;
int chars_; // Caches the number of characters when computing the hash code.
uint32_t seed_;
};
template <typename Char>
class SequentialSymbolKey : public HashTableKey {
public:
explicit SequentialSymbolKey(Vector<const Char> string, uint32_t seed)
: string_(string), hash_field_(0), seed_(seed) { }
uint32_t Hash() {
StringHasher hasher(string_.length(), seed_);
// Very long strings have a trivial hash that doesn't inspect the
// string contents.
if (hasher.has_trivial_hash()) {
hash_field_ = hasher.GetHashField();
} else {
int i = 0;
// Do the iterative array index computation as long as there is a
// chance this is an array index.
while (i < string_.length() && hasher.is_array_index()) {
hasher.AddCharacter(static_cast<uc32>(string_[i]));
i++;
}
// Process the remaining characters without updating the array
// index.
while (i < string_.length()) {
hasher.AddCharacterNoIndex(static_cast<uc32>(string_[i]));
i++;
}
hash_field_ = hasher.GetHashField();
}
uint32_t result = hash_field_ >> String::kHashShift;
ASSERT(result != 0); // Ensure that the hash value of 0 is never computed.
return result;
}
uint32_t HashForObject(Object* other) {
return String::cast(other)->Hash();
}
Vector<const Char> string_;
uint32_t hash_field_;
uint32_t seed_;
};
class AsciiSymbolKey : public SequentialSymbolKey<char> {
public:
AsciiSymbolKey(Vector<const char> str, uint32_t seed)
: SequentialSymbolKey<char>(str, seed) { }
bool IsMatch(Object* string) {
return String::cast(string)->IsAsciiEqualTo(string_);
}
MaybeObject* AsObject() {
if (hash_field_ == 0) Hash();
return HEAP->AllocateAsciiSymbol(string_, hash_field_);
}
};
class SubStringAsciiSymbolKey : public HashTableKey {
public:
explicit SubStringAsciiSymbolKey(Handle<SeqAsciiString> string,
int from,
int length,
uint32_t seed)
: string_(string), from_(from), length_(length), seed_(seed) { }
uint32_t Hash() {
ASSERT(length_ >= 0);
ASSERT(from_ + length_ <= string_->length());
StringHasher hasher(length_, string_->GetHeap()->HashSeed());
// Very long strings have a trivial hash that doesn't inspect the
// string contents.
if (hasher.has_trivial_hash()) {
hash_field_ = hasher.GetHashField();
} else {
int i = 0;
// Do the iterative array index computation as long as there is a
// chance this is an array index.
while (i < length_ && hasher.is_array_index()) {
hasher.AddCharacter(static_cast<uc32>(
string_->SeqAsciiStringGet(i + from_)));
i++;
}
// Process the remaining characters without updating the array
// index.
while (i < length_) {
hasher.AddCharacterNoIndex(static_cast<uc32>(
string_->SeqAsciiStringGet(i + from_)));
i++;
}
hash_field_ = hasher.GetHashField();
}
uint32_t result = hash_field_ >> String::kHashShift;
ASSERT(result != 0); // Ensure that the hash value of 0 is never computed.
return result;
}
uint32_t HashForObject(Object* other) {
return String::cast(other)->Hash();
}
bool IsMatch(Object* string) {
Vector<const char> chars(string_->GetChars() + from_, length_);
return String::cast(string)->IsAsciiEqualTo(chars);
}
MaybeObject* AsObject() {
if (hash_field_ == 0) Hash();
Vector<const char> chars(string_->GetChars() + from_, length_);
return HEAP->AllocateAsciiSymbol(chars, hash_field_);
}
private:
Handle<SeqAsciiString> string_;
int from_;
int length_;
uint32_t hash_field_;
uint32_t seed_;
};
class TwoByteSymbolKey : public SequentialSymbolKey<uc16> {
public:
explicit TwoByteSymbolKey(Vector<const uc16> str, uint32_t seed)
: SequentialSymbolKey<uc16>(str, seed) { }
bool IsMatch(Object* string) {
return String::cast(string)->IsTwoByteEqualTo(string_);
}
MaybeObject* AsObject() {
if (hash_field_ == 0) Hash();
return HEAP->AllocateTwoByteSymbol(string_, hash_field_);
}
};
// SymbolKey carries a string/symbol object as key.
class SymbolKey : public HashTableKey {
public:
explicit SymbolKey(String* string)
: string_(string) { }
bool IsMatch(Object* string) {
return String::cast(string)->Equals(string_);
}
uint32_t Hash() { return string_->Hash(); }
uint32_t HashForObject(Object* other) {
return String::cast(other)->Hash();
}
MaybeObject* AsObject() {
// Attempt to flatten the string, so that symbols will most often
// be flat strings.
string_ = string_->TryFlattenGetString();
Heap* heap = string_->GetHeap();
// Transform string to symbol if possible.
Map* map = heap->SymbolMapForString(string_);
if (map != NULL) {
string_->set_map_no_write_barrier(map);
ASSERT(string_->IsSymbol());
return string_;
}
// Otherwise allocate a new symbol.
StringInputBuffer buffer(string_);
return heap->AllocateInternalSymbol(&buffer,
string_->length(),
string_->hash_field());
}
static uint32_t StringHash(Object* obj) {
return String::cast(obj)->Hash();
}
String* string_;
};
template<typename Shape, typename Key>
void HashTable<Shape, Key>::IteratePrefix(ObjectVisitor* v) {
IteratePointers(v, 0, kElementsStartOffset);
}
template<typename Shape, typename Key>
void HashTable<Shape, Key>::IterateElements(ObjectVisitor* v) {
IteratePointers(v,
kElementsStartOffset,
kHeaderSize + length() * kPointerSize);
}
template<typename Shape, typename Key>
MaybeObject* HashTable<Shape, Key>::Allocate(int at_least_space_for,
PretenureFlag pretenure) {
int capacity = ComputeCapacity(at_least_space_for);
if (capacity > HashTable::kMaxCapacity) {
return Failure::OutOfMemoryException();
}
Object* obj;
{ MaybeObject* maybe_obj = Isolate::Current()->heap()->
AllocateHashTable(EntryToIndex(capacity), pretenure);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
HashTable::cast(obj)->SetNumberOfElements(0);
HashTable::cast(obj)->SetNumberOfDeletedElements(0);
HashTable::cast(obj)->SetCapacity(capacity);
return obj;
}
// Find entry for key otherwise return kNotFound.
int StringDictionary::FindEntry(String* key) {
if (!key->IsSymbol()) {
return HashTable<StringDictionaryShape, String*>::FindEntry(key);
}
// Optimized for symbol key. Knowledge of the key type allows:
// 1. Move the check if the key is a symbol out of the loop.
// 2. Avoid comparing hash codes in symbol to symbol comparison.
// 3. Detect a case when a dictionary key is not a symbol but the key is.
// In case of positive result the dictionary key may be replaced by
// the symbol with minimal performance penalty. It gives a chance to
// perform further lookups in code stubs (and significant performance boost
// a certain style of code).
// EnsureCapacity will guarantee the hash table is never full.
uint32_t capacity = Capacity();
uint32_t entry = FirstProbe(key->Hash(), capacity);
uint32_t count = 1;
while (true) {
int index = EntryToIndex(entry);
Object* element = get(index);
if (element->IsUndefined()) break; // Empty entry.
if (key == element) return entry;
if (!element->IsSymbol() &&
!element->IsTheHole() &&
String::cast(element)->Equals(key)) {
// Replace a non-symbol key by the equivalent symbol for faster further
// lookups.
set(index, key);
return entry;
}
ASSERT(element->IsTheHole() || !String::cast(element)->Equals(key));
entry = NextProbe(entry, count++, capacity);
}
return kNotFound;
}
bool StringDictionary::ContainsTransition(int entry) {
switch (DetailsAt(entry).type()) {
case MAP_TRANSITION:
case CONSTANT_TRANSITION:
case ELEMENTS_TRANSITION:
return true;
case CALLBACKS: {
Object* value = ValueAt(entry);
if (!value->IsAccessorPair()) return false;
AccessorPair* accessors = AccessorPair::cast(value);
return accessors->getter()->IsMap() || accessors->setter()->IsMap();
}
case NORMAL:
case FIELD:
case CONSTANT_FUNCTION:
case HANDLER:
case INTERCEPTOR:
case NULL_DESCRIPTOR:
return false;
}
UNREACHABLE(); // Keep the compiler happy.
return false;
}
template<typename Shape, typename Key>
MaybeObject* HashTable<Shape, Key>::Rehash(HashTable* new_table, Key key) {
ASSERT(NumberOfElements() < new_table->Capacity());
AssertNoAllocation no_gc;
WriteBarrierMode mode = new_table->GetWriteBarrierMode(no_gc);
// Copy prefix to new array.
for (int i = kPrefixStartIndex;
i < kPrefixStartIndex + Shape::kPrefixSize;
i++) {
new_table->set(i, get(i), mode);
}
// Rehash the elements.
int capacity = Capacity();
for (int i = 0; i < capacity; i++) {
uint32_t from_index = EntryToIndex(i);
Object* k = get(from_index);
if (IsKey(k)) {
uint32_t hash = HashTable<Shape, Key>::HashForObject(key, k);
uint32_t insertion_index =
EntryToIndex(new_table->FindInsertionEntry(hash));
for (int j = 0; j < Shape::kEntrySize; j++) {
new_table->set(insertion_index + j, get(from_index + j), mode);
}
}
}
new_table->SetNumberOfElements(NumberOfElements());
new_table->SetNumberOfDeletedElements(0);
return new_table;
}
template<typename Shape, typename Key>
MaybeObject* HashTable<Shape, Key>::EnsureCapacity(int n, Key key) {
int capacity = Capacity();
int nof = NumberOfElements() + n;
int nod = NumberOfDeletedElements();
// Return if:
// 50% is still free after adding n elements and
// at most 50% of the free elements are deleted elements.
if (nod <= (capacity - nof) >> 1) {
int needed_free = nof >> 1;
if (nof + needed_free <= capacity) return this;
}
const int kMinCapacityForPretenure = 256;
bool pretenure =
(capacity > kMinCapacityForPretenure) && !GetHeap()->InNewSpace(this);
Object* obj;
{ MaybeObject* maybe_obj =
Allocate(nof * 2, pretenure ? TENURED : NOT_TENURED);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return Rehash(HashTable::cast(obj), key);
}
template<typename Shape, typename Key>
MaybeObject* HashTable<Shape, Key>::Shrink(Key key) {
int capacity = Capacity();
int nof = NumberOfElements();
// Shrink to fit the number of elements if only a quarter of the
// capacity is filled with elements.
if (nof > (capacity >> 2)) return this;
// Allocate a new dictionary with room for at least the current
// number of elements. The allocation method will make sure that
// there is extra room in the dictionary for additions. Don't go
// lower than room for 16 elements.
int at_least_room_for = nof;
if (at_least_room_for < 16) return this;
const int kMinCapacityForPretenure = 256;
bool pretenure =
(at_least_room_for > kMinCapacityForPretenure) &&
!GetHeap()->InNewSpace(this);
Object* obj;
{ MaybeObject* maybe_obj =
Allocate(at_least_room_for, pretenure ? TENURED : NOT_TENURED);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return Rehash(HashTable::cast(obj), key);
}
template<typename Shape, typename Key>
uint32_t HashTable<Shape, Key>::FindInsertionEntry(uint32_t hash) {
uint32_t capacity = Capacity();
uint32_t entry = FirstProbe(hash, capacity);
uint32_t count = 1;
// EnsureCapacity will guarantee the hash table is never full.
while (true) {
Object* element = KeyAt(entry);
if (element->IsUndefined() || element->IsTheHole()) break;
entry = NextProbe(entry, count++, capacity);
}
return entry;
}
// Force instantiation of template instances class.
// Please note this list is compiler dependent.
template class HashTable<SymbolTableShape, HashTableKey*>;
template class HashTable<CompilationCacheShape, HashTableKey*>;
template class HashTable<MapCacheShape, HashTableKey*>;
template class HashTable<ObjectHashTableShape<1>, Object*>;
template class HashTable<ObjectHashTableShape<2>, Object*>;
template class Dictionary<StringDictionaryShape, String*>;
template class Dictionary<SeededNumberDictionaryShape, uint32_t>;
template class Dictionary<UnseededNumberDictionaryShape, uint32_t>;
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::
Allocate(int at_least_space_for);
template MaybeObject* Dictionary<UnseededNumberDictionaryShape, uint32_t>::
Allocate(int at_least_space_for);
template MaybeObject* Dictionary<StringDictionaryShape, String*>::Allocate(
int);
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::AtPut(
uint32_t, Object*);
template MaybeObject* Dictionary<UnseededNumberDictionaryShape, uint32_t>::
AtPut(uint32_t, Object*);
template Object* Dictionary<SeededNumberDictionaryShape, uint32_t>::
SlowReverseLookup(Object* value);
template Object* Dictionary<UnseededNumberDictionaryShape, uint32_t>::
SlowReverseLookup(Object* value);
template Object* Dictionary<StringDictionaryShape, String*>::SlowReverseLookup(
Object*);
template void Dictionary<SeededNumberDictionaryShape, uint32_t>::CopyKeysTo(
FixedArray*,
PropertyAttributes,
Dictionary<SeededNumberDictionaryShape, uint32_t>::SortMode);
template Object* Dictionary<StringDictionaryShape, String*>::DeleteProperty(
int, JSObject::DeleteMode);
template Object* Dictionary<SeededNumberDictionaryShape, uint32_t>::
DeleteProperty(int, JSObject::DeleteMode);
template MaybeObject* Dictionary<StringDictionaryShape, String*>::Shrink(
String*);
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::Shrink(
uint32_t);
template void Dictionary<StringDictionaryShape, String*>::CopyKeysTo(
FixedArray*,
int,
Dictionary<StringDictionaryShape, String*>::SortMode);
template int
Dictionary<StringDictionaryShape, String*>::NumberOfElementsFilterAttributes(
PropertyAttributes);
template MaybeObject* Dictionary<StringDictionaryShape, String*>::Add(
String*, Object*, PropertyDetails);
template MaybeObject*
Dictionary<StringDictionaryShape, String*>::GenerateNewEnumerationIndices();
template int
Dictionary<SeededNumberDictionaryShape, uint32_t>::
NumberOfElementsFilterAttributes(PropertyAttributes);
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::Add(
uint32_t, Object*, PropertyDetails);
template MaybeObject* Dictionary<UnseededNumberDictionaryShape, uint32_t>::Add(
uint32_t, Object*, PropertyDetails);
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::
EnsureCapacity(int, uint32_t);
template MaybeObject* Dictionary<UnseededNumberDictionaryShape, uint32_t>::
EnsureCapacity(int, uint32_t);
template MaybeObject* Dictionary<StringDictionaryShape, String*>::
EnsureCapacity(int, String*);
template MaybeObject* Dictionary<SeededNumberDictionaryShape, uint32_t>::
AddEntry(uint32_t, Object*, PropertyDetails, uint32_t);
template MaybeObject* Dictionary<UnseededNumberDictionaryShape, uint32_t>::
AddEntry(uint32_t, Object*, PropertyDetails, uint32_t);
template MaybeObject* Dictionary<StringDictionaryShape, String*>::AddEntry(
String*, Object*, PropertyDetails, uint32_t);
template
int Dictionary<SeededNumberDictionaryShape, uint32_t>::NumberOfEnumElements();
template
int Dictionary<StringDictionaryShape, String*>::NumberOfEnumElements();
template
int HashTable<SeededNumberDictionaryShape, uint32_t>::FindEntry(uint32_t);
// Collates undefined and unexisting elements below limit from position
// zero of the elements. The object stays in Dictionary mode.
MaybeObject* JSObject::PrepareSlowElementsForSort(uint32_t limit) {
ASSERT(HasDictionaryElements());
// Must stay in dictionary mode, either because of requires_slow_elements,
// or because we are not going to sort (and therefore compact) all of the
// elements.
SeededNumberDictionary* dict = element_dictionary();
HeapNumber* result_double = NULL;
if (limit > static_cast<uint32_t>(Smi::kMaxValue)) {
// Allocate space for result before we start mutating the object.
Object* new_double;
{ MaybeObject* maybe_new_double = GetHeap()->AllocateHeapNumber(0.0);
if (!maybe_new_double->ToObject(&new_double)) return maybe_new_double;
}
result_double = HeapNumber::cast(new_double);
}
Object* obj;
{ MaybeObject* maybe_obj =
SeededNumberDictionary::Allocate(dict->NumberOfElements());
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
SeededNumberDictionary* new_dict = SeededNumberDictionary::cast(obj);
AssertNoAllocation no_alloc;
uint32_t pos = 0;
uint32_t undefs = 0;
int capacity = dict->Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = dict->KeyAt(i);
if (dict->IsKey(k)) {
ASSERT(k->IsNumber());
ASSERT(!k->IsSmi() || Smi::cast(k)->value() >= 0);
ASSERT(!k->IsHeapNumber() || HeapNumber::cast(k)->value() >= 0);
ASSERT(!k->IsHeapNumber() || HeapNumber::cast(k)->value() <= kMaxUInt32);
Object* value = dict->ValueAt(i);
PropertyDetails details = dict->DetailsAt(i);
if (details.type() == CALLBACKS) {
// Bail out and do the sorting of undefineds and array holes in JS.
return Smi::FromInt(-1);
}
uint32_t key = NumberToUint32(k);
// In the following we assert that adding the entry to the new dictionary
// does not cause GC. This is the case because we made sure to allocate
// the dictionary big enough above, so it need not grow.
if (key < limit) {
if (value->IsUndefined()) {
undefs++;
} else {
if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return Smi::FromInt(-1);
}
new_dict->AddNumberEntry(pos, value, details)->ToObjectUnchecked();
pos++;
}
} else {
if (key > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return Smi::FromInt(-1);
}
new_dict->AddNumberEntry(key, value, details)->ToObjectUnchecked();
}
}
}
uint32_t result = pos;
PropertyDetails no_details = PropertyDetails(NONE, NORMAL);
Heap* heap = GetHeap();
while (undefs > 0) {
if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return Smi::FromInt(-1);
}
new_dict->AddNumberEntry(pos, heap->undefined_value(), no_details)->
ToObjectUnchecked();
pos++;
undefs--;
}
set_elements(new_dict);
if (result <= static_cast<uint32_t>(Smi::kMaxValue)) {
return Smi::FromInt(static_cast<int>(result));
}
ASSERT_NE(NULL, result_double);
result_double->set_value(static_cast<double>(result));
return result_double;
}
// Collects all defined (non-hole) and non-undefined (array) elements at
// the start of the elements array.
// If the object is in dictionary mode, it is converted to fast elements
// mode.
MaybeObject* JSObject::PrepareElementsForSort(uint32_t limit) {
Heap* heap = GetHeap();
if (HasDictionaryElements()) {
// Convert to fast elements containing only the existing properties.
// Ordering is irrelevant, since we are going to sort anyway.
SeededNumberDictionary* dict = element_dictionary();
if (IsJSArray() || dict->requires_slow_elements() ||
dict->max_number_key() >= limit) {
return PrepareSlowElementsForSort(limit);
}
// Convert to fast elements.
Object* obj;
{ MaybeObject* maybe_obj = GetElementsTransitionMap(GetIsolate(),
FAST_ELEMENTS);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
Map* new_map = Map::cast(obj);
PretenureFlag tenure = heap->InNewSpace(this) ? NOT_TENURED: TENURED;
Object* new_array;
{ MaybeObject* maybe_new_array =
heap->AllocateFixedArray(dict->NumberOfElements(), tenure);
if (!maybe_new_array->ToObject(&new_array)) return maybe_new_array;
}
FixedArray* fast_elements = FixedArray::cast(new_array);
dict->CopyValuesTo(fast_elements);
set_map(new_map);
set_elements(fast_elements);
} else if (HasExternalArrayElements()) {
// External arrays cannot have holes or undefined elements.
return Smi::FromInt(ExternalArray::cast(elements())->length());
} else if (!HasFastDoubleElements()) {
Object* obj;
{ MaybeObject* maybe_obj = EnsureWritableFastElements();
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
}
ASSERT(HasFastTypeElements() || HasFastDoubleElements());
// Collect holes at the end, undefined before that and the rest at the
// start, and return the number of non-hole, non-undefined values.
FixedArrayBase* elements_base = FixedArrayBase::cast(this->elements());
uint32_t elements_length = static_cast<uint32_t>(elements_base->length());
if (limit > elements_length) {
limit = elements_length ;
}
if (limit == 0) {
return Smi::FromInt(0);
}
HeapNumber* result_double = NULL;
if (limit > static_cast<uint32_t>(Smi::kMaxValue)) {
// Pessimistically allocate space for return value before
// we start mutating the array.
Object* new_double;
{ MaybeObject* maybe_new_double = heap->AllocateHeapNumber(0.0);
if (!maybe_new_double->ToObject(&new_double)) return maybe_new_double;
}
result_double = HeapNumber::cast(new_double);
}
uint32_t result = 0;
if (elements_base->map() == heap->fixed_double_array_map()) {
FixedDoubleArray* elements = FixedDoubleArray::cast(elements_base);
// Split elements into defined and the_hole, in that order.
unsigned int holes = limit;
// Assume most arrays contain no holes and undefined values, so minimize the
// number of stores of non-undefined, non-the-hole values.
for (unsigned int i = 0; i < holes; i++) {
if (elements->is_the_hole(i)) {
holes--;
} else {
continue;
}
// Position i needs to be filled.
while (holes > i) {
if (elements->is_the_hole(holes)) {
holes--;
} else {
elements->set(i, elements->get_scalar(holes));
break;
}
}
}
result = holes;
while (holes < limit) {
elements->set_the_hole(holes);
holes++;
}
} else {
FixedArray* elements = FixedArray::cast(elements_base);
AssertNoAllocation no_alloc;
// Split elements into defined, undefined and the_hole, in that order. Only
// count locations for undefined and the hole, and fill them afterwards.
WriteBarrierMode write_barrier = elements->GetWriteBarrierMode(no_alloc);
unsigned int undefs = limit;
unsigned int holes = limit;
// Assume most arrays contain no holes and undefined values, so minimize the
// number of stores of non-undefined, non-the-hole values.
for (unsigned int i = 0; i < undefs; i++) {
Object* current = elements->get(i);
if (current->IsTheHole()) {
holes--;
undefs--;
} else if (current->IsUndefined()) {
undefs--;
} else {
continue;
}
// Position i needs to be filled.
while (undefs > i) {
current = elements->get(undefs);
if (current->IsTheHole()) {
holes--;
undefs--;
} else if (current->IsUndefined()) {
undefs--;
} else {
elements->set(i, current, write_barrier);
break;
}
}
}
result = undefs;
while (undefs < holes) {
elements->set_undefined(undefs);
undefs++;
}
while (holes < limit) {
elements->set_the_hole(holes);
holes++;
}
}
if (result <= static_cast<uint32_t>(Smi::kMaxValue)) {
return Smi::FromInt(static_cast<int>(result));
}
ASSERT_NE(NULL, result_double);
result_double->set_value(static_cast<double>(result));
return result_double;
}
Object* ExternalPixelArray::SetValue(uint32_t index, Object* value) {
uint8_t clamped_value = 0;
if (index < static_cast<uint32_t>(length())) {
if (value->IsSmi()) {
int int_value = Smi::cast(value)->value();
if (int_value < 0) {
clamped_value = 0;
} else if (int_value > 255) {
clamped_value = 255;
} else {
clamped_value = static_cast<uint8_t>(int_value);
}
} else if (value->IsHeapNumber()) {
double double_value = HeapNumber::cast(value)->value();
if (!(double_value > 0)) {
// NaN and less than zero clamp to zero.
clamped_value = 0;
} else if (double_value > 255) {
// Greater than 255 clamp to 255.
clamped_value = 255;
} else {
// Other doubles are rounded to the nearest integer.
clamped_value = static_cast<uint8_t>(double_value + 0.5);
}
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
ASSERT(value->IsUndefined());
}
set(index, clamped_value);
}
return Smi::FromInt(clamped_value);
}
template<typename ExternalArrayClass, typename ValueType>
static MaybeObject* ExternalArrayIntSetter(Heap* heap,
ExternalArrayClass* receiver,
uint32_t index,
Object* value) {
ValueType cast_value = 0;
if (index < static_cast<uint32_t>(receiver->length())) {
if (value->IsSmi()) {
int int_value = Smi::cast(value)->value();
cast_value = static_cast<ValueType>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = HeapNumber::cast(value)->value();
cast_value = static_cast<ValueType>(DoubleToInt32(double_value));
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
ASSERT(value->IsUndefined());
}
receiver->set(index, cast_value);
}
return heap->NumberFromInt32(cast_value);
}
MaybeObject* ExternalByteArray::SetValue(uint32_t index, Object* value) {
return ExternalArrayIntSetter<ExternalByteArray, int8_t>
(GetHeap(), this, index, value);
}
MaybeObject* ExternalUnsignedByteArray::SetValue(uint32_t index,
Object* value) {
return ExternalArrayIntSetter<ExternalUnsignedByteArray, uint8_t>
(GetHeap(), this, index, value);
}
MaybeObject* ExternalShortArray::SetValue(uint32_t index,
Object* value) {
return ExternalArrayIntSetter<ExternalShortArray, int16_t>
(GetHeap(), this, index, value);
}
MaybeObject* ExternalUnsignedShortArray::SetValue(uint32_t index,
Object* value) {
return ExternalArrayIntSetter<ExternalUnsignedShortArray, uint16_t>
(GetHeap(), this, index, value);
}
MaybeObject* ExternalIntArray::SetValue(uint32_t index, Object* value) {
return ExternalArrayIntSetter<ExternalIntArray, int32_t>
(GetHeap(), this, index, value);
}
MaybeObject* ExternalUnsignedIntArray::SetValue(uint32_t index, Object* value) {
uint32_t cast_value = 0;
Heap* heap = GetHeap();
if (index < static_cast<uint32_t>(length())) {
if (value->IsSmi()) {
int int_value = Smi::cast(value)->value();
cast_value = static_cast<uint32_t>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = HeapNumber::cast(value)->value();
cast_value = static_cast<uint32_t>(DoubleToUint32(double_value));
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
ASSERT(value->IsUndefined());
}
set(index, cast_value);
}
return heap->NumberFromUint32(cast_value);
}
MaybeObject* ExternalFloatArray::SetValue(uint32_t index, Object* value) {
float cast_value = static_cast<float>(OS::nan_value());
Heap* heap = GetHeap();
if (index < static_cast<uint32_t>(length())) {
if (value->IsSmi()) {
int int_value = Smi::cast(value)->value();
cast_value = static_cast<float>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = HeapNumber::cast(value)->value();
cast_value = static_cast<float>(double_value);
} else {
// Clamp undefined to NaN (default). All other types have been
// converted to a number type further up in the call chain.
ASSERT(value->IsUndefined());
}
set(index, cast_value);
}
return heap->AllocateHeapNumber(cast_value);
}
MaybeObject* ExternalDoubleArray::SetValue(uint32_t index, Object* value) {
double double_value = OS::nan_value();
Heap* heap = GetHeap();
if (index < static_cast<uint32_t>(length())) {
if (value->IsSmi()) {
int int_value = Smi::cast(value)->value();
double_value = static_cast<double>(int_value);
} else if (value->IsHeapNumber()) {
double_value = HeapNumber::cast(value)->value();
} else {
// Clamp undefined to NaN (default). All other types have been
// converted to a number type further up in the call chain.
ASSERT(value->IsUndefined());
}
set(index, double_value);
}
return heap->AllocateHeapNumber(double_value);
}
JSGlobalPropertyCell* GlobalObject::GetPropertyCell(LookupResult* result) {
ASSERT(!HasFastProperties());
Object* value = property_dictionary()->ValueAt(result->GetDictionaryEntry());
return JSGlobalPropertyCell::cast(value);
}
Handle<JSGlobalPropertyCell> GlobalObject::EnsurePropertyCell(
Handle<GlobalObject> global,
Handle<String> name) {
Isolate* isolate = global->GetIsolate();
CALL_HEAP_FUNCTION(isolate,
global->EnsurePropertyCell(*name),
JSGlobalPropertyCell);
}
MaybeObject* GlobalObject::EnsurePropertyCell(String* name) {
ASSERT(!HasFastProperties());
int entry = property_dictionary()->FindEntry(name);
if (entry == StringDictionary::kNotFound) {
Heap* heap = GetHeap();
Object* cell;
{ MaybeObject* maybe_cell =
heap->AllocateJSGlobalPropertyCell(heap->the_hole_value());
if (!maybe_cell->ToObject(&cell)) return maybe_cell;
}
PropertyDetails details(NONE, NORMAL);
details = details.AsDeleted();
Object* dictionary;
{ MaybeObject* maybe_dictionary =
property_dictionary()->Add(name, cell, details);
if (!maybe_dictionary->ToObject(&dictionary)) return maybe_dictionary;
}
set_properties(StringDictionary::cast(dictionary));
return cell;
} else {
Object* value = property_dictionary()->ValueAt(entry);
ASSERT(value->IsJSGlobalPropertyCell());
return value;
}
}
MaybeObject* SymbolTable::LookupString(String* string, Object** s) {
SymbolKey key(string);
return LookupKey(&key, s);
}
// This class is used for looking up two character strings in the symbol table.
// If we don't have a hit we don't want to waste much time so we unroll the
// string hash calculation loop here for speed. Doesn't work if the two
// characters form a decimal integer, since such strings have a different hash
// algorithm.
class TwoCharHashTableKey : public HashTableKey {
public:
TwoCharHashTableKey(uint32_t c1, uint32_t c2, uint32_t seed)
: c1_(c1), c2_(c2) {
// Char 1.
uint32_t hash = seed;
hash += c1;
hash += hash << 10;
hash ^= hash >> 6;
// Char 2.
hash += c2;
hash += hash << 10;
hash ^= hash >> 6;
// GetHash.
hash += hash << 3;
hash ^= hash >> 11;
hash += hash << 15;
if ((hash & String::kHashBitMask) == 0) hash = String::kZeroHash;
#ifdef DEBUG
StringHasher hasher(2, seed);
hasher.AddCharacter(c1);
hasher.AddCharacter(c2);
// If this assert fails then we failed to reproduce the two-character
// version of the string hashing algorithm above. One reason could be
// that we were passed two digits as characters, since the hash
// algorithm is different in that case.
ASSERT_EQ(static_cast<int>(hasher.GetHash()), static_cast<int>(hash));
#endif
hash_ = hash;
}
bool IsMatch(Object* o) {
if (!o->IsString()) return false;
String* other = String::cast(o);
if (other->length() != 2) return false;
if (other->Get(0) != c1_) return false;
return other->Get(1) == c2_;
}
uint32_t Hash() { return hash_; }
uint32_t HashForObject(Object* key) {
if (!key->IsString()) return 0;
return String::cast(key)->Hash();
}
Object* AsObject() {
// The TwoCharHashTableKey is only used for looking in the symbol
// table, not for adding to it.
UNREACHABLE();
return NULL;
}
private:
uint32_t c1_;
uint32_t c2_;
uint32_t hash_;
};
bool SymbolTable::LookupSymbolIfExists(String* string, String** symbol) {
SymbolKey key(string);
int entry = FindEntry(&key);
if (entry == kNotFound) {
return false;
} else {
String* result = String::cast(KeyAt(entry));
ASSERT(StringShape(result).IsSymbol());
*symbol = result;
return true;
}
}
bool SymbolTable::LookupTwoCharsSymbolIfExists(uint32_t c1,
uint32_t c2,
String** symbol) {
TwoCharHashTableKey key(c1, c2, GetHeap()->HashSeed());
int entry = FindEntry(&key);
if (entry == kNotFound) {
return false;
} else {
String* result = String::cast(KeyAt(entry));
ASSERT(StringShape(result).IsSymbol());
*symbol = result;
return true;
}
}
MaybeObject* SymbolTable::LookupSymbol(Vector<const char> str,
Object** s) {
Utf8SymbolKey key(str, GetHeap()->HashSeed());
return LookupKey(&key, s);
}
MaybeObject* SymbolTable::LookupAsciiSymbol(Vector<const char> str,
Object** s) {
AsciiSymbolKey key(str, GetHeap()->HashSeed());
return LookupKey(&key, s);
}
MaybeObject* SymbolTable::LookupSubStringAsciiSymbol(Handle<SeqAsciiString> str,
int from,
int length,
Object** s) {
SubStringAsciiSymbolKey key(str, from, length, GetHeap()->HashSeed());
return LookupKey(&key, s);
}
MaybeObject* SymbolTable::LookupTwoByteSymbol(Vector<const uc16> str,
Object** s) {
TwoByteSymbolKey key(str, GetHeap()->HashSeed());
return LookupKey(&key, s);
}
MaybeObject* SymbolTable::LookupKey(HashTableKey* key, Object** s) {
int entry = FindEntry(key);
// Symbol already in table.
if (entry != kNotFound) {
*s = KeyAt(entry);
return this;
}
// Adding new symbol. Grow table if needed.
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
// Create symbol object.
Object* symbol;
{ MaybeObject* maybe_symbol = key->AsObject();
if (!maybe_symbol->ToObject(&symbol)) return maybe_symbol;
}
// If the symbol table grew as part of EnsureCapacity, obj is not
// the current symbol table and therefore we cannot use
// SymbolTable::cast here.
SymbolTable* table = reinterpret_cast<SymbolTable*>(obj);
// Add the new symbol and return it along with the symbol table.
entry = table->FindInsertionEntry(key->Hash());
table->set(EntryToIndex(entry), symbol);
table->ElementAdded();
*s = symbol;
return table;
}
Object* CompilationCacheTable::Lookup(String* src) {
StringKey key(src);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
Object* CompilationCacheTable::LookupEval(String* src,
Context* context,
LanguageMode language_mode,
int scope_position) {
StringSharedKey key(src,
context->closure()->shared(),
language_mode,
scope_position);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
Object* CompilationCacheTable::LookupRegExp(String* src,
JSRegExp::Flags flags) {
RegExpKey key(src, flags);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
MaybeObject* CompilationCacheTable::Put(String* src, Object* value) {
StringKey key(src);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
CompilationCacheTable* cache =
reinterpret_cast<CompilationCacheTable*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
cache->set(EntryToIndex(entry), src);
cache->set(EntryToIndex(entry) + 1, value);
cache->ElementAdded();
return cache;
}
MaybeObject* CompilationCacheTable::PutEval(String* src,
Context* context,
SharedFunctionInfo* value,
int scope_position) {
StringSharedKey key(src,
context->closure()->shared(),
value->language_mode(),
scope_position);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
CompilationCacheTable* cache =
reinterpret_cast<CompilationCacheTable*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
Object* k;
{ MaybeObject* maybe_k = key.AsObject();
if (!maybe_k->ToObject(&k)) return maybe_k;
}
cache->set(EntryToIndex(entry), k);
cache->set(EntryToIndex(entry) + 1, value);
cache->ElementAdded();
return cache;
}
MaybeObject* CompilationCacheTable::PutRegExp(String* src,
JSRegExp::Flags flags,
FixedArray* value) {
RegExpKey key(src, flags);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
CompilationCacheTable* cache =
reinterpret_cast<CompilationCacheTable*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
// We store the value in the key slot, and compare the search key
// to the stored value with a custon IsMatch function during lookups.
cache->set(EntryToIndex(entry), value);
cache->set(EntryToIndex(entry) + 1, value);
cache->ElementAdded();
return cache;
}
void CompilationCacheTable::Remove(Object* value) {
Object* the_hole_value = GetHeap()->the_hole_value();
for (int entry = 0, size = Capacity(); entry < size; entry++) {
int entry_index = EntryToIndex(entry);
int value_index = entry_index + 1;
if (get(value_index) == value) {
NoWriteBarrierSet(this, entry_index, the_hole_value);
NoWriteBarrierSet(this, value_index, the_hole_value);
ElementRemoved();
}
}
return;
}
// SymbolsKey used for HashTable where key is array of symbols.
class SymbolsKey : public HashTableKey {
public:
explicit SymbolsKey(FixedArray* symbols) : symbols_(symbols) { }
bool IsMatch(Object* symbols) {
FixedArray* o = FixedArray::cast(symbols);
int len = symbols_->length();
if (o->length() != len) return false;
for (int i = 0; i < len; i++) {
if (o->get(i) != symbols_->get(i)) return false;
}
return true;
}
uint32_t Hash() { return HashForObject(symbols_); }
uint32_t HashForObject(Object* obj) {
FixedArray* symbols = FixedArray::cast(obj);
int len = symbols->length();
uint32_t hash = 0;
for (int i = 0; i < len; i++) {
hash ^= String::cast(symbols->get(i))->Hash();
}
return hash;
}
Object* AsObject() { return symbols_; }
private:
FixedArray* symbols_;
};
Object* MapCache::Lookup(FixedArray* array) {
SymbolsKey key(array);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
MaybeObject* MapCache::Put(FixedArray* array, Map* value) {
SymbolsKey key(array);
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, &key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
MapCache* cache = reinterpret_cast<MapCache*>(obj);
int entry = cache->FindInsertionEntry(key.Hash());
cache->set(EntryToIndex(entry), array);
cache->set(EntryToIndex(entry) + 1, value);
cache->ElementAdded();
return cache;
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::Allocate(int at_least_space_for) {
Object* obj;
{ MaybeObject* maybe_obj =
HashTable<Shape, Key>::Allocate(at_least_space_for);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
// Initialize the next enumeration index.
Dictionary<Shape, Key>::cast(obj)->
SetNextEnumerationIndex(PropertyDetails::kInitialIndex);
return obj;
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::GenerateNewEnumerationIndices() {
Heap* heap = Dictionary<Shape, Key>::GetHeap();
int length = HashTable<Shape, Key>::NumberOfElements();
// Allocate and initialize iteration order array.
Object* obj;
{ MaybeObject* maybe_obj = heap->AllocateFixedArray(length);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* iteration_order = FixedArray::cast(obj);
for (int i = 0; i < length; i++) {
iteration_order->set(i, Smi::FromInt(i));
}
// Allocate array with enumeration order.
{ MaybeObject* maybe_obj = heap->AllocateFixedArray(length);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
FixedArray* enumeration_order = FixedArray::cast(obj);
// Fill the enumeration order array with property details.
int capacity = HashTable<Shape, Key>::Capacity();
int pos = 0;
for (int i = 0; i < capacity; i++) {
if (Dictionary<Shape, Key>::IsKey(Dictionary<Shape, Key>::KeyAt(i))) {
enumeration_order->set(pos++, Smi::FromInt(DetailsAt(i).index()));
}
}
// Sort the arrays wrt. enumeration order.
iteration_order->SortPairs(enumeration_order, enumeration_order->length());
// Overwrite the enumeration_order with the enumeration indices.
for (int i = 0; i < length; i++) {
int index = Smi::cast(iteration_order->get(i))->value();
int enum_index = PropertyDetails::kInitialIndex + i;
enumeration_order->set(index, Smi::FromInt(enum_index));
}
// Update the dictionary with new indices.
capacity = HashTable<Shape, Key>::Capacity();
pos = 0;
for (int i = 0; i < capacity; i++) {
if (Dictionary<Shape, Key>::IsKey(Dictionary<Shape, Key>::KeyAt(i))) {
int enum_index = Smi::cast(enumeration_order->get(pos++))->value();
PropertyDetails details = DetailsAt(i);
PropertyDetails new_details =
PropertyDetails(details.attributes(), details.type(), enum_index);
DetailsAtPut(i, new_details);
}
}
// Set the next enumeration index.
SetNextEnumerationIndex(PropertyDetails::kInitialIndex+length);
return this;
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::EnsureCapacity(int n, Key key) {
// Check whether there are enough enumeration indices to add n elements.
if (Shape::kIsEnumerable &&
!PropertyDetails::IsValidIndex(NextEnumerationIndex() + n)) {
// If not, we generate new indices for the properties.
Object* result;
{ MaybeObject* maybe_result = GenerateNewEnumerationIndices();
if (!maybe_result->ToObject(&result)) return maybe_result;
}
}
return HashTable<Shape, Key>::EnsureCapacity(n, key);
}
template<typename Shape, typename Key>
Object* Dictionary<Shape, Key>::DeleteProperty(int entry,
JSReceiver::DeleteMode mode) {
Heap* heap = Dictionary<Shape, Key>::GetHeap();
PropertyDetails details = DetailsAt(entry);
// Ignore attributes if forcing a deletion.
if (details.IsDontDelete() && mode != JSReceiver::FORCE_DELETION) {
return heap->false_value();
}
SetEntry(entry, heap->the_hole_value(), heap->the_hole_value());
HashTable<Shape, Key>::ElementRemoved();
return heap->true_value();
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::Shrink(Key key) {
return HashTable<Shape, Key>::Shrink(key);
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::AtPut(Key key, Object* value) {
int entry = this->FindEntry(key);
// If the entry is present set the value;
if (entry != Dictionary<Shape, Key>::kNotFound) {
ValueAtPut(entry, value);
return this;
}
// Check whether the dictionary should be extended.
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
Object* k;
{ MaybeObject* maybe_k = Shape::AsObject(key);
if (!maybe_k->ToObject(&k)) return maybe_k;
}
PropertyDetails details = PropertyDetails(NONE, NORMAL);
return Dictionary<Shape, Key>::cast(obj)->AddEntry(key, value, details,
Dictionary<Shape, Key>::Hash(key));
}
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::Add(Key key,
Object* value,
PropertyDetails details) {
// Valdate key is absent.
SLOW_ASSERT((this->FindEntry(key) == Dictionary<Shape, Key>::kNotFound));
// Check whether the dictionary should be extended.
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
return Dictionary<Shape, Key>::cast(obj)->AddEntry(key, value, details,
Dictionary<Shape, Key>::Hash(key));
}
// Add a key, value pair to the dictionary.
template<typename Shape, typename Key>
MaybeObject* Dictionary<Shape, Key>::AddEntry(Key key,
Object* value,
PropertyDetails details,
uint32_t hash) {
// Compute the key object.
Object* k;
{ MaybeObject* maybe_k = Shape::AsObject(key);
if (!maybe_k->ToObject(&k)) return maybe_k;
}
uint32_t entry = Dictionary<Shape, Key>::FindInsertionEntry(hash);
// Insert element at empty or deleted entry
if (!details.IsDeleted() && details.index() == 0 && Shape::kIsEnumerable) {
// Assign an enumeration index to the property and update
// SetNextEnumerationIndex.
int index = NextEnumerationIndex();
details = PropertyDetails(details.attributes(), details.type(), index);
SetNextEnumerationIndex(index + 1);
}
SetEntry(entry, k, value, details);
ASSERT((Dictionary<Shape, Key>::KeyAt(entry)->IsNumber()
|| Dictionary<Shape, Key>::KeyAt(entry)->IsString()));
HashTable<Shape, Key>::ElementAdded();
return this;
}
void SeededNumberDictionary::UpdateMaxNumberKey(uint32_t key) {
// If the dictionary requires slow elements an element has already
// been added at a high index.
if (requires_slow_elements()) return;
// Check if this index is high enough that we should require slow
// elements.
if (key > kRequiresSlowElementsLimit) {
set_requires_slow_elements();
return;
}
// Update max key value.
Object* max_index_object = get(kMaxNumberKeyIndex);
if (!max_index_object->IsSmi() || max_number_key() < key) {
FixedArray::set(kMaxNumberKeyIndex,
Smi::FromInt(key << kRequiresSlowElementsTagSize));
}
}
MaybeObject* SeededNumberDictionary::AddNumberEntry(uint32_t key,
Object* value,
PropertyDetails details) {
UpdateMaxNumberKey(key);
SLOW_ASSERT(this->FindEntry(key) == kNotFound);
return Add(key, value, details);
}
MaybeObject* UnseededNumberDictionary::AddNumberEntry(uint32_t key,
Object* value) {
SLOW_ASSERT(this->FindEntry(key) == kNotFound);
return Add(key, value, PropertyDetails(NONE, NORMAL));
}
MaybeObject* SeededNumberDictionary::AtNumberPut(uint32_t key, Object* value) {
UpdateMaxNumberKey(key);
return AtPut(key, value);
}
MaybeObject* UnseededNumberDictionary::AtNumberPut(uint32_t key,
Object* value) {
return AtPut(key, value);
}
Handle<SeededNumberDictionary> SeededNumberDictionary::Set(
Handle<SeededNumberDictionary> dictionary,
uint32_t index,
Handle<Object> value,
PropertyDetails details) {
CALL_HEAP_FUNCTION(dictionary->GetIsolate(),
dictionary->Set(index, *value, details),
SeededNumberDictionary);
}
Handle<UnseededNumberDictionary> UnseededNumberDictionary::Set(
Handle<UnseededNumberDictionary> dictionary,
uint32_t index,
Handle<Object> value) {
CALL_HEAP_FUNCTION(dictionary->GetIsolate(),
dictionary->Set(index, *value),
UnseededNumberDictionary);
}
MaybeObject* SeededNumberDictionary::Set(uint32_t key,
Object* value,
PropertyDetails details) {
int entry = FindEntry(key);
if (entry == kNotFound) return AddNumberEntry(key, value, details);
// Preserve enumeration index.
details = PropertyDetails(details.attributes(),
details.type(),
DetailsAt(entry).index());
MaybeObject* maybe_object_key = SeededNumberDictionaryShape::AsObject(key);
Object* object_key;
if (!maybe_object_key->ToObject(&object_key)) return maybe_object_key;
SetEntry(entry, object_key, value, details);
return this;
}
MaybeObject* UnseededNumberDictionary::Set(uint32_t key,
Object* value) {
int entry = FindEntry(key);
if (entry == kNotFound) return AddNumberEntry(key, value);
MaybeObject* maybe_object_key = UnseededNumberDictionaryShape::AsObject(key);
Object* object_key;
if (!maybe_object_key->ToObject(&object_key)) return maybe_object_key;
SetEntry(entry, object_key, value);
return this;
}
template<typename Shape, typename Key>
int Dictionary<Shape, Key>::NumberOfElementsFilterAttributes(
PropertyAttributes filter) {
int capacity = HashTable<Shape, Key>::Capacity();
int result = 0;
for (int i = 0; i < capacity; i++) {
Object* k = HashTable<Shape, Key>::KeyAt(i);
if (HashTable<Shape, Key>::IsKey(k)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
PropertyAttributes attr = details.attributes();
if ((attr & filter) == 0) result++;
}
}
return result;
}
template<typename Shape, typename Key>
int Dictionary<Shape, Key>::NumberOfEnumElements() {
return NumberOfElementsFilterAttributes(
static_cast<PropertyAttributes>(DONT_ENUM));
}
template<typename Shape, typename Key>
void Dictionary<Shape, Key>::CopyKeysTo(
FixedArray* storage,
PropertyAttributes filter,
typename Dictionary<Shape, Key>::SortMode sort_mode) {
ASSERT(storage->length() >= NumberOfEnumElements());
int capacity = HashTable<Shape, Key>::Capacity();
int index = 0;
for (int i = 0; i < capacity; i++) {
Object* k = HashTable<Shape, Key>::KeyAt(i);
if (HashTable<Shape, Key>::IsKey(k)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
PropertyAttributes attr = details.attributes();
if ((attr & filter) == 0) storage->set(index++, k);
}
}
if (sort_mode == Dictionary<Shape, Key>::SORTED) {
storage->SortPairs(storage, index);
}
ASSERT(storage->length() >= index);
}
void StringDictionary::CopyEnumKeysTo(FixedArray* storage,
FixedArray* sort_array) {
ASSERT(storage->length() >= NumberOfEnumElements());
int capacity = Capacity();
int index = 0;
for (int i = 0; i < capacity; i++) {
Object* k = KeyAt(i);
if (IsKey(k)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted() || details.IsDontEnum()) continue;
storage->set(index, k);
sort_array->set(index, Smi::FromInt(details.index()));
index++;
}
}
storage->SortPairs(sort_array, sort_array->length());
ASSERT(storage->length() >= index);
}
template<typename Shape, typename Key>
void Dictionary<Shape, Key>::CopyKeysTo(
FixedArray* storage,
int index,
typename Dictionary<Shape, Key>::SortMode sort_mode) {
ASSERT(storage->length() >= NumberOfElementsFilterAttributes(
static_cast<PropertyAttributes>(NONE)));
int capacity = HashTable<Shape, Key>::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = HashTable<Shape, Key>::KeyAt(i);
if (HashTable<Shape, Key>::IsKey(k)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
storage->set(index++, k);
}
}
if (sort_mode == Dictionary<Shape, Key>::SORTED) {
storage->SortPairs(storage, index);
}
ASSERT(storage->length() >= index);
}
// Backwards lookup (slow).
template<typename Shape, typename Key>
Object* Dictionary<Shape, Key>::SlowReverseLookup(Object* value) {
int capacity = HashTable<Shape, Key>::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = HashTable<Shape, Key>::KeyAt(i);
if (Dictionary<Shape, Key>::IsKey(k)) {
Object* e = ValueAt(i);
if (e->IsJSGlobalPropertyCell()) {
e = JSGlobalPropertyCell::cast(e)->value();
}
if (e == value) return k;
}
}
Heap* heap = Dictionary<Shape, Key>::GetHeap();
return heap->undefined_value();
}
MaybeObject* StringDictionary::TransformPropertiesToFastFor(
JSObject* obj, int unused_property_fields) {
// Make sure we preserve dictionary representation if there are too many
// descriptors.
if (NumberOfElements() > DescriptorArray::kMaxNumberOfDescriptors) return obj;
// Figure out if it is necessary to generate new enumeration indices.
int max_enumeration_index =
NextEnumerationIndex() +
(DescriptorArray::kMaxNumberOfDescriptors -
NumberOfElements());
if (!PropertyDetails::IsValidIndex(max_enumeration_index)) {
Object* result;
{ MaybeObject* maybe_result = GenerateNewEnumerationIndices();
if (!maybe_result->ToObject(&result)) return maybe_result;
}
}
int instance_descriptor_length = 0;
int number_of_fields = 0;
Heap* heap = GetHeap();
// Compute the length of the instance descriptor.
int capacity = Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = KeyAt(i);
if (IsKey(k)) {
Object* value = ValueAt(i);
PropertyType type = DetailsAt(i).type();
ASSERT(type != FIELD);
instance_descriptor_length++;
if (type == NORMAL &&
(!value->IsJSFunction() || heap->InNewSpace(value))) {
number_of_fields += 1;
}
}
}
// Allocate the instance descriptor.
DescriptorArray* descriptors;
{ MaybeObject* maybe_descriptors =
DescriptorArray::Allocate(instance_descriptor_length);
if (!maybe_descriptors->To<DescriptorArray>(&descriptors)) {
return maybe_descriptors;
}
}
DescriptorArray::WhitenessWitness witness(descriptors);
int inobject_props = obj->map()->inobject_properties();
int number_of_allocated_fields =
number_of_fields + unused_property_fields - inobject_props;
if (number_of_allocated_fields < 0) {
// There is enough inobject space for all fields (including unused).
number_of_allocated_fields = 0;
unused_property_fields = inobject_props - number_of_fields;
}
// Allocate the fixed array for the fields.
Object* fields;
{ MaybeObject* maybe_fields =
heap->AllocateFixedArray(number_of_allocated_fields);
if (!maybe_fields->ToObject(&fields)) return maybe_fields;
}
// Fill in the instance descriptor and the fields.
int next_descriptor = 0;
int current_offset = 0;
for (int i = 0; i < capacity; i++) {
Object* k = KeyAt(i);
if (IsKey(k)) {
Object* value = ValueAt(i);
// Ensure the key is a symbol before writing into the instance descriptor.
Object* key;
{ MaybeObject* maybe_key = heap->LookupSymbol(String::cast(k));
if (!maybe_key->ToObject(&key)) return maybe_key;
}
PropertyDetails details = DetailsAt(i);
PropertyType type = details.type();
if (value->IsJSFunction() && !heap->InNewSpace(value)) {
ConstantFunctionDescriptor d(String::cast(key),
JSFunction::cast(value),
details.attributes(),
details.index());
descriptors->Set(next_descriptor++, &d, witness);
} else if (type == NORMAL) {
if (current_offset < inobject_props) {
obj->InObjectPropertyAtPut(current_offset,
value,
UPDATE_WRITE_BARRIER);
} else {
int offset = current_offset - inobject_props;
FixedArray::cast(fields)->set(offset, value);
}
FieldDescriptor d(String::cast(key),
current_offset++,
details.attributes(),
details.index());
descriptors->Set(next_descriptor++, &d, witness);
} else if (type == CALLBACKS) {
if (value->IsAccessorPair()) {
MaybeObject* maybe_copy =
AccessorPair::cast(value)->CopyWithoutTransitions();
if (!maybe_copy->To(&value)) return maybe_copy;
}
CallbacksDescriptor d(String::cast(key),
value,
details.attributes(),
details.index());
descriptors->Set(next_descriptor++, &d, witness);
} else {
UNREACHABLE();
}
}
}
ASSERT(current_offset == number_of_fields);
descriptors->Sort(witness);
// Allocate new map.
Object* new_map;
{ MaybeObject* maybe_new_map = obj->map()->CopyDropDescriptors();
if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
}
// Transform the object.
obj->set_map(Map::cast(new_map));
obj->map()->set_instance_descriptors(descriptors);
obj->map()->set_unused_property_fields(unused_property_fields);
obj->set_properties(FixedArray::cast(fields));
ASSERT(obj->IsJSObject());
descriptors->SetNextEnumerationIndex(NextEnumerationIndex());
// Check that it really works.
ASSERT(obj->HasFastProperties());
return obj;
}
bool ObjectHashSet::Contains(Object* key) {
ASSERT(IsKey(key));
// If the object does not have an identity hash, it was never used as a key.
{ MaybeObject* maybe_hash = key->GetHash(OMIT_CREATION);
if (maybe_hash->ToObjectUnchecked()->IsUndefined()) return false;
}
return (FindEntry(key) != kNotFound);
}
MaybeObject* ObjectHashSet::Add(Object* key) {
ASSERT(IsKey(key));
// Make sure the key object has an identity hash code.
int hash;
{ MaybeObject* maybe_hash = key->GetHash(ALLOW_CREATION);
if (maybe_hash->IsFailure()) return maybe_hash;
hash = Smi::cast(maybe_hash->ToObjectUnchecked())->value();
}
int entry = FindEntry(key);
// Check whether key is already present.
if (entry != kNotFound) return this;
// Check whether the hash set should be extended and add entry.
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
ObjectHashSet* table = ObjectHashSet::cast(obj);
entry = table->FindInsertionEntry(hash);
table->set(EntryToIndex(entry), key);
table->ElementAdded();
return table;
}
MaybeObject* ObjectHashSet::Remove(Object* key) {
ASSERT(IsKey(key));
// If the object does not have an identity hash, it was never used as a key.
{ MaybeObject* maybe_hash = key->GetHash(OMIT_CREATION);
if (maybe_hash->ToObjectUnchecked()->IsUndefined()) return this;
}
int entry = FindEntry(key);
// Check whether key is actually present.
if (entry == kNotFound) return this;
// Remove entry and try to shrink this hash set.
set_the_hole(EntryToIndex(entry));
ElementRemoved();
return Shrink(key);
}
Object* ObjectHashTable::Lookup(Object* key) {
ASSERT(IsKey(key));
// If the object does not have an identity hash, it was never used as a key.
{ MaybeObject* maybe_hash = key->GetHash(OMIT_CREATION);
if (maybe_hash->ToObjectUnchecked()->IsUndefined()) {
return GetHeap()->undefined_value();
}
}
int entry = FindEntry(key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
MaybeObject* ObjectHashTable::Put(Object* key, Object* value) {
ASSERT(IsKey(key));
// Make sure the key object has an identity hash code.
int hash;
{ MaybeObject* maybe_hash = key->GetHash(ALLOW_CREATION);
if (maybe_hash->IsFailure()) return maybe_hash;
hash = Smi::cast(maybe_hash->ToObjectUnchecked())->value();
}
int entry = FindEntry(key);
// Check whether to perform removal operation.
if (value->IsUndefined()) {
if (entry == kNotFound) return this;
RemoveEntry(entry);
return Shrink(key);
}
// Key is already in table, just overwrite value.
if (entry != kNotFound) {
set(EntryToIndex(entry) + 1, value);
return this;
}
// Check whether the hash table should be extended.
Object* obj;
{ MaybeObject* maybe_obj = EnsureCapacity(1, key);
if (!maybe_obj->ToObject(&obj)) return maybe_obj;
}
ObjectHashTable* table = ObjectHashTable::cast(obj);
table->AddEntry(table->FindInsertionEntry(hash), key, value);
return table;
}
void ObjectHashTable::AddEntry(int entry, Object* key, Object* value) {
set(EntryToIndex(entry), key);
set(EntryToIndex(entry) + 1, value);
ElementAdded();
}
void ObjectHashTable::RemoveEntry(int entry) {
set_the_hole(EntryToIndex(entry));
set_the_hole(EntryToIndex(entry) + 1);
ElementRemoved();
}
#ifdef ENABLE_DEBUGGER_SUPPORT
// Check if there is a break point at this code position.
bool DebugInfo::HasBreakPoint(int code_position) {
// Get the break point info object for this code position.
Object* break_point_info = GetBreakPointInfo(code_position);
// If there is no break point info object or no break points in the break
// point info object there is no break point at this code position.
if (break_point_info->IsUndefined()) return false;
return BreakPointInfo::cast(break_point_info)->GetBreakPointCount() > 0;
}
// Get the break point info object for this code position.
Object* DebugInfo::GetBreakPointInfo(int code_position) {
// Find the index of the break point info object for this code position.
int index = GetBreakPointInfoIndex(code_position);
// Return the break point info object if any.
if (index == kNoBreakPointInfo) return GetHeap()->undefined_value();
return BreakPointInfo::cast(break_points()->get(index));
}
// Clear a break point at the specified code position.
void DebugInfo::ClearBreakPoint(Handle<DebugInfo> debug_info,
int code_position,
Handle<Object> break_point_object) {
Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position));
if (break_point_info->IsUndefined()) return;
BreakPointInfo::ClearBreakPoint(
Handle<BreakPointInfo>::cast(break_point_info),
break_point_object);
}
void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
int code_position,
int source_position,
int statement_position,
Handle<Object> break_point_object) {
Isolate* isolate = Isolate::Current();
Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position));
if (!break_point_info->IsUndefined()) {
BreakPointInfo::SetBreakPoint(
Handle<BreakPointInfo>::cast(break_point_info),
break_point_object);
return;
}
// Adding a new break point for a code position which did not have any
// break points before. Try to find a free slot.
int index = kNoBreakPointInfo;
for (int i = 0; i < debug_info->break_points()->length(); i++) {
if (debug_info->break_points()->get(i)->IsUndefined()) {
index = i;
break;
}
}
if (index == kNoBreakPointInfo) {
// No free slot - extend break point info array.
Handle<FixedArray> old_break_points =
Handle<FixedArray>(FixedArray::cast(debug_info->break_points()));
Handle<FixedArray> new_break_points =
isolate->factory()->NewFixedArray(
old_break_points->length() +
Debug::kEstimatedNofBreakPointsInFunction);
debug_info->set_break_points(*new_break_points);
for (int i = 0; i < old_break_points->length(); i++) {
new_break_points->set(i, old_break_points->get(i));
}
index = old_break_points->length();
}
ASSERT(index != kNoBreakPointInfo);
// Allocate new BreakPointInfo object and set the break point.
Handle<BreakPointInfo> new_break_point_info = Handle<BreakPointInfo>::cast(
isolate->factory()->NewStruct(BREAK_POINT_INFO_TYPE));
new_break_point_info->set_code_position(Smi::FromInt(code_position));
new_break_point_info->set_source_position(Smi::FromInt(source_position));
new_break_point_info->
set_statement_position(Smi::FromInt(statement_position));
new_break_point_info->set_break_point_objects(
isolate->heap()->undefined_value());
BreakPointInfo::SetBreakPoint(new_break_point_info, break_point_object);
debug_info->break_points()->set(index, *new_break_point_info);
}
// Get the break point objects for a code position.
Object* DebugInfo::GetBreakPointObjects(int code_position) {
Object* break_point_info = GetBreakPointInfo(code_position);
if (break_point_info->IsUndefined()) {
return GetHeap()->undefined_value();
}
return BreakPointInfo::cast(break_point_info)->break_point_objects();
}
// Get the total number of break points.
int DebugInfo::GetBreakPointCount() {
if (break_points()->IsUndefined()) return 0;
int count = 0;
for (int i = 0; i < break_points()->length(); i++) {
if (!break_points()->get(i)->IsUndefined()) {
BreakPointInfo* break_point_info =
BreakPointInfo::cast(break_points()->get(i));
count += break_point_info->GetBreakPointCount();
}
}
return count;
}
Object* DebugInfo::FindBreakPointInfo(Handle<DebugInfo> debug_info,
Handle<Object> break_point_object) {
Heap* heap = debug_info->GetHeap();
if (debug_info->break_points()->IsUndefined()) return heap->undefined_value();
for (int i = 0; i < debug_info->break_points()->length(); i++) {
if (!debug_info->break_points()->get(i)->IsUndefined()) {
Handle<BreakPointInfo> break_point_info =
Handle<BreakPointInfo>(BreakPointInfo::cast(
debug_info->break_points()->get(i)));
if (BreakPointInfo::HasBreakPointObject(break_point_info,
break_point_object)) {
return *break_point_info;
}
}
}
return heap->undefined_value();
}
// Find the index of the break point info object for the specified code
// position.
int DebugInfo::GetBreakPointInfoIndex(int code_position) {
if (break_points()->IsUndefined()) return kNoBreakPointInfo;
for (int i = 0; i < break_points()->length(); i++) {
if (!break_points()->get(i)->IsUndefined()) {
BreakPointInfo* break_point_info =
BreakPointInfo::cast(break_points()->get(i));
if (break_point_info->code_position()->value() == code_position) {
return i;
}
}
}
return kNoBreakPointInfo;
}
// Remove the specified break point object.
void BreakPointInfo::ClearBreakPoint(Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
Isolate* isolate = Isolate::Current();
// If there are no break points just ignore.
if (break_point_info->break_point_objects()->IsUndefined()) return;
// If there is a single break point clear it if it is the same.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
if (break_point_info->break_point_objects() == *break_point_object) {
break_point_info->set_break_point_objects(
isolate->heap()->undefined_value());
}
return;
}
// If there are multiple break points shrink the array
ASSERT(break_point_info->break_point_objects()->IsFixedArray());
Handle<FixedArray> old_array =
Handle<FixedArray>(
FixedArray::cast(break_point_info->break_point_objects()));
Handle<FixedArray> new_array =
isolate->factory()->NewFixedArray(old_array->length() - 1);
int found_count = 0;
for (int i = 0; i < old_array->length(); i++) {
if (old_array->get(i) == *break_point_object) {
ASSERT(found_count == 0);
found_count++;
} else {
new_array->set(i - found_count, old_array->get(i));
}
}
// If the break point was found in the list change it.
if (found_count > 0) break_point_info->set_break_point_objects(*new_array);
}
// Add the specified break point object.
void BreakPointInfo::SetBreakPoint(Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
// If there was no break point objects before just set it.
if (break_point_info->break_point_objects()->IsUndefined()) {
break_point_info->set_break_point_objects(*break_point_object);
return;
}
// If the break point object is the same as before just ignore.
if (break_point_info->break_point_objects() == *break_point_object) return;
// If there was one break point object before replace with array.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
Handle<FixedArray> array = FACTORY->NewFixedArray(2);
array->set(0, break_point_info->break_point_objects());
array->set(1, *break_point_object);
break_point_info->set_break_point_objects(*array);
return;
}
// If there was more than one break point before extend array.
Handle<FixedArray> old_array =
Handle<FixedArray>(
FixedArray::cast(break_point_info->break_point_objects()));
Handle<FixedArray> new_array =
FACTORY->NewFixedArray(old_array->length() + 1);
for (int i = 0; i < old_array->length(); i++) {
// If the break point was there before just ignore.
if (old_array->get(i) == *break_point_object) return;
new_array->set(i, old_array->get(i));
}
// Add the new break point.
new_array->set(old_array->length(), *break_point_object);
break_point_info->set_break_point_objects(*new_array);
}
bool BreakPointInfo::HasBreakPointObject(
Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
// No break point.
if (break_point_info->break_point_objects()->IsUndefined()) return false;
// Single break point.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
return break_point_info->break_point_objects() == *break_point_object;
}
// Multiple break points.
FixedArray* array = FixedArray::cast(break_point_info->break_point_objects());
for (int i = 0; i < array->length(); i++) {
if (array->get(i) == *break_point_object) {
return true;
}
}
return false;
}
// Get the number of break points.
int BreakPointInfo::GetBreakPointCount() {
// No break point.
if (break_point_objects()->IsUndefined()) return 0;
// Single break point.
if (!break_point_objects()->IsFixedArray()) return 1;
// Multiple break points.
return FixedArray::cast(break_point_objects())->length();
}
#endif // ENABLE_DEBUGGER_SUPPORT
MaybeObject* JSDate::GetField(Object* object, Smi* index) {
return JSDate::cast(object)->DoGetField(
static_cast<FieldIndex>(index->value()));
}
Object* JSDate::DoGetField(FieldIndex index) {
ASSERT(index != kDateValue);
DateCache* date_cache = GetIsolate()->date_cache();
if (index < kFirstUncachedField) {
Object* stamp = cache_stamp();
if (stamp != date_cache->stamp() && stamp->IsSmi()) {
// Since the stamp is not NaN, the value is also not NaN.
int64_t local_time_ms =
date_cache->ToLocal(static_cast<int64_t>(value()->Number()));
SetLocalFields(local_time_ms, date_cache);
}
switch (index) {
case kYear: return year();
case kMonth: return month();
case kDay: return day();
case kWeekday: return weekday();
case kHour: return hour();
case kMinute: return min();
case kSecond: return sec();
default: UNREACHABLE();
}
}
if (index >= kFirstUTCField) {
return GetUTCField(index, value()->Number(), date_cache);
}
double time = value()->Number();
if (isnan(time)) return GetIsolate()->heap()->nan_value();
int64_t local_time_ms = date_cache->ToLocal(static_cast<int64_t>(time));
int days = DateCache::DaysFromTime(local_time_ms);
if (index == kDays) return Smi::FromInt(days);
int time_in_day_ms = DateCache::TimeInDay(local_time_ms, days);
if (index == kMillisecond) return Smi::FromInt(time_in_day_ms % 1000);
ASSERT(index == kTimeInDay);
return Smi::FromInt(time_in_day_ms);
}
Object* JSDate::GetUTCField(FieldIndex index,
double value,
DateCache* date_cache) {
ASSERT(index >= kFirstUTCField);
if (isnan(value)) return GetIsolate()->heap()->nan_value();
int64_t time_ms = static_cast<int64_t>(value);
if (index == kTimezoneOffset) {
return Smi::FromInt(date_cache->TimezoneOffset(time_ms));
}
int days = DateCache::DaysFromTime(time_ms);
if (index == kWeekdayUTC) return Smi::FromInt(date_cache->Weekday(days));
if (index <= kDayUTC) {
int year, month, day;
date_cache->YearMonthDayFromDays(days, &year, &month, &day);
if (index == kYearUTC) return Smi::FromInt(year);
if (index == kMonthUTC) return Smi::FromInt(month);
ASSERT(index == kDayUTC);
return Smi::FromInt(day);
}
int time_in_day_ms = DateCache::TimeInDay(time_ms, days);
switch (index) {
case kHourUTC: return Smi::FromInt(time_in_day_ms / (60 * 60 * 1000));
case kMinuteUTC: return Smi::FromInt((time_in_day_ms / (60 * 1000)) % 60);
case kSecondUTC: return Smi::FromInt((time_in_day_ms / 1000) % 60);
case kMillisecondUTC: return Smi::FromInt(time_in_day_ms % 1000);
case kDaysUTC: return Smi::FromInt(days);
case kTimeInDayUTC: return Smi::FromInt(time_in_day_ms);
default: UNREACHABLE();
}
UNREACHABLE();
return NULL;
}
void JSDate::SetValue(Object* value, bool is_value_nan) {
set_value(value);
if (is_value_nan) {
HeapNumber* nan = GetIsolate()->heap()->nan_value();
set_cache_stamp(nan, SKIP_WRITE_BARRIER);
set_year(nan, SKIP_WRITE_BARRIER);
set_month(nan, SKIP_WRITE_BARRIER);
set_day(nan, SKIP_WRITE_BARRIER);
set_hour(nan, SKIP_WRITE_BARRIER);
set_min(nan, SKIP_WRITE_BARRIER);
set_sec(nan, SKIP_WRITE_BARRIER);
set_weekday(nan, SKIP_WRITE_BARRIER);
} else {
set_cache_stamp(Smi::FromInt(DateCache::kInvalidStamp), SKIP_WRITE_BARRIER);
}
}
void JSDate::SetLocalFields(int64_t local_time_ms, DateCache* date_cache) {
int days = DateCache::DaysFromTime(local_time_ms);
int time_in_day_ms = DateCache::TimeInDay(local_time_ms, days);
int year, month, day;
date_cache->YearMonthDayFromDays(days, &year, &month, &day);
int weekday = date_cache->Weekday(days);
int hour = time_in_day_ms / (60 * 60 * 1000);
int min = (time_in_day_ms / (60 * 1000)) % 60;
int sec = (time_in_day_ms / 1000) % 60;
set_cache_stamp(date_cache->stamp());
set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
}
} } // namespace v8::internal