// Copyright 2010 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 "bootstrapper.h"
#include "codegen-inl.h"
#include "compiler.h"
#include "debug.h"
#include "ic-inl.h"
#include "jsregexp.h"
#include "parser.h"
#include "regexp-macro-assembler.h"
#include "regexp-stack.h"
#include "register-allocator-inl.h"
#include "runtime.h"
#include "scopes.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm_)
// -------------------------------------------------------------------------
// Platform-specific DeferredCode functions.
void DeferredCode::SaveRegisters() {
for (int i = 0; i < RegisterAllocator::kNumRegisters; i++) {
int action = registers_[i];
if (action == kPush) {
__ push(RegisterAllocator::ToRegister(i));
} else if (action != kIgnore && (action & kSyncedFlag) == 0) {
__ mov(Operand(ebp, action), RegisterAllocator::ToRegister(i));
}
}
}
void DeferredCode::RestoreRegisters() {
// Restore registers in reverse order due to the stack.
for (int i = RegisterAllocator::kNumRegisters - 1; i >= 0; i--) {
int action = registers_[i];
if (action == kPush) {
__ pop(RegisterAllocator::ToRegister(i));
} else if (action != kIgnore) {
action &= ~kSyncedFlag;
__ mov(RegisterAllocator::ToRegister(i), Operand(ebp, action));
}
}
}
// -------------------------------------------------------------------------
// CodeGenState implementation.
CodeGenState::CodeGenState(CodeGenerator* owner)
: owner_(owner),
destination_(NULL),
previous_(NULL) {
owner_->set_state(this);
}
CodeGenState::CodeGenState(CodeGenerator* owner,
ControlDestination* destination)
: owner_(owner),
destination_(destination),
previous_(owner->state()) {
owner_->set_state(this);
}
CodeGenState::~CodeGenState() {
ASSERT(owner_->state() == this);
owner_->set_state(previous_);
}
// -------------------------------------------------------------------------
// CodeGenerator implementation
CodeGenerator::CodeGenerator(MacroAssembler* masm)
: deferred_(8),
masm_(masm),
info_(NULL),
frame_(NULL),
allocator_(NULL),
state_(NULL),
loop_nesting_(0),
function_return_is_shadowed_(false),
in_spilled_code_(false) {
}
Scope* CodeGenerator::scope() { return info_->function()->scope(); }
// Calling conventions:
// ebp: caller's frame pointer
// esp: stack pointer
// edi: called JS function
// esi: callee's context
void CodeGenerator::Generate(CompilationInfo* info) {
// Record the position for debugging purposes.
CodeForFunctionPosition(info->function());
// Initialize state.
info_ = info;
ASSERT(allocator_ == NULL);
RegisterAllocator register_allocator(this);
allocator_ = ®ister_allocator;
ASSERT(frame_ == NULL);
frame_ = new VirtualFrame();
set_in_spilled_code(false);
// Adjust for function-level loop nesting.
loop_nesting_ += info->loop_nesting();
JumpTarget::set_compiling_deferred_code(false);
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
frame_->SpillAll();
__ int3();
}
#endif
// New scope to get automatic timing calculation.
{ // NOLINT
HistogramTimerScope codegen_timer(&Counters::code_generation);
CodeGenState state(this);
// Entry:
// Stack: receiver, arguments, return address.
// ebp: caller's frame pointer
// esp: stack pointer
// edi: called JS function
// esi: callee's context
allocator_->Initialize();
if (info->mode() == CompilationInfo::PRIMARY) {
frame_->Enter();
// Allocate space for locals and initialize them.
frame_->AllocateStackSlots();
// Allocate the local context if needed.
int heap_slots = scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
if (heap_slots > 0) {
Comment cmnt(masm_, "[ allocate local context");
// Allocate local context.
// Get outer context and create a new context based on it.
frame_->PushFunction();
Result context;
if (heap_slots <= FastNewContextStub::kMaximumSlots) {
FastNewContextStub stub(heap_slots);
context = frame_->CallStub(&stub, 1);
} else {
context = frame_->CallRuntime(Runtime::kNewContext, 1);
}
// Update context local.
frame_->SaveContextRegister();
// Verify that the runtime call result and esi agree.
if (FLAG_debug_code) {
__ cmp(context.reg(), Operand(esi));
__ Assert(equal, "Runtime::NewContext should end up in esi");
}
}
// TODO(1241774): Improve this code:
// 1) only needed if we have a context
// 2) no need to recompute context ptr every single time
// 3) don't copy parameter operand code from SlotOperand!
{
Comment cmnt2(masm_, "[ copy context parameters into .context");
// Note that iteration order is relevant here! If we have the same
// parameter twice (e.g., function (x, y, x)), and that parameter
// needs to be copied into the context, it must be the last argument
// passed to the parameter that needs to be copied. This is a rare
// case so we don't check for it, instead we rely on the copying
// order: such a parameter is copied repeatedly into the same
// context location and thus the last value is what is seen inside
// the function.
for (int i = 0; i < scope()->num_parameters(); i++) {
Variable* par = scope()->parameter(i);
Slot* slot = par->slot();
if (slot != NULL && slot->type() == Slot::CONTEXT) {
// The use of SlotOperand below is safe in unspilled code
// because the slot is guaranteed to be a context slot.
//
// There are no parameters in the global scope.
ASSERT(!scope()->is_global_scope());
frame_->PushParameterAt(i);
Result value = frame_->Pop();
value.ToRegister();
// SlotOperand loads context.reg() with the context object
// stored to, used below in RecordWrite.
Result context = allocator_->Allocate();
ASSERT(context.is_valid());
__ mov(SlotOperand(slot, context.reg()), value.reg());
int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
frame_->Spill(context.reg());
frame_->Spill(value.reg());
__ RecordWrite(context.reg(), offset, value.reg(), scratch.reg());
}
}
}
// Store the arguments object. This must happen after context
// initialization because the arguments object may be stored in
// the context.
if (ArgumentsMode() != NO_ARGUMENTS_ALLOCATION) {
StoreArgumentsObject(true);
}
// Initialize ThisFunction reference if present.
if (scope()->is_function_scope() && scope()->function() != NULL) {
frame_->Push(Factory::the_hole_value());
StoreToSlot(scope()->function()->slot(), NOT_CONST_INIT);
}
} else {
// When used as the secondary compiler for splitting, ebp, esi,
// and edi have been pushed on the stack. Adjust the virtual
// frame to match this state.
frame_->Adjust(3);
allocator_->Unuse(edi);
// Bind all the bailout labels to the beginning of the function.
List<CompilationInfo::Bailout*>* bailouts = info->bailouts();
for (int i = 0; i < bailouts->length(); i++) {
__ bind(bailouts->at(i)->label());
}
}
// Initialize the function return target after the locals are set
// up, because it needs the expected frame height from the frame.
function_return_.set_direction(JumpTarget::BIDIRECTIONAL);
function_return_is_shadowed_ = false;
// Generate code to 'execute' declarations and initialize functions
// (source elements). In case of an illegal redeclaration we need to
// handle that instead of processing the declarations.
if (scope()->HasIllegalRedeclaration()) {
Comment cmnt(masm_, "[ illegal redeclarations");
scope()->VisitIllegalRedeclaration(this);
} else {
Comment cmnt(masm_, "[ declarations");
ProcessDeclarations(scope()->declarations());
// Bail out if a stack-overflow exception occurred when processing
// declarations.
if (HasStackOverflow()) return;
}
if (FLAG_trace) {
frame_->CallRuntime(Runtime::kTraceEnter, 0);
// Ignore the return value.
}
CheckStack();
// Compile the body of the function in a vanilla state. Don't
// bother compiling all the code if the scope has an illegal
// redeclaration.
if (!scope()->HasIllegalRedeclaration()) {
Comment cmnt(masm_, "[ function body");
#ifdef DEBUG
bool is_builtin = Bootstrapper::IsActive();
bool should_trace =
is_builtin ? FLAG_trace_builtin_calls : FLAG_trace_calls;
if (should_trace) {
frame_->CallRuntime(Runtime::kDebugTrace, 0);
// Ignore the return value.
}
#endif
VisitStatements(info->function()->body());
// Handle the return from the function.
if (has_valid_frame()) {
// If there is a valid frame, control flow can fall off the end of
// the body. In that case there is an implicit return statement.
ASSERT(!function_return_is_shadowed_);
CodeForReturnPosition(info->function());
frame_->PrepareForReturn();
Result undefined(Factory::undefined_value());
if (function_return_.is_bound()) {
function_return_.Jump(&undefined);
} else {
function_return_.Bind(&undefined);
GenerateReturnSequence(&undefined);
}
} else if (function_return_.is_linked()) {
// If the return target has dangling jumps to it, then we have not
// yet generated the return sequence. This can happen when (a)
// control does not flow off the end of the body so we did not
// compile an artificial return statement just above, and (b) there
// are return statements in the body but (c) they are all shadowed.
Result return_value;
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}
}
// Adjust for function-level loop nesting.
loop_nesting_ -= info->loop_nesting();
// Code generation state must be reset.
ASSERT(state_ == NULL);
ASSERT(loop_nesting() == 0);
ASSERT(!function_return_is_shadowed_);
function_return_.Unuse();
DeleteFrame();
// Process any deferred code using the register allocator.
if (!HasStackOverflow()) {
HistogramTimerScope deferred_timer(&Counters::deferred_code_generation);
JumpTarget::set_compiling_deferred_code(true);
ProcessDeferred();
JumpTarget::set_compiling_deferred_code(false);
}
// There is no need to delete the register allocator, it is a
// stack-allocated local.
allocator_ = NULL;
}
Operand CodeGenerator::SlotOperand(Slot* slot, Register tmp) {
// Currently, this assertion will fail if we try to assign to
// a constant variable that is constant because it is read-only
// (such as the variable referring to a named function expression).
// We need to implement assignments to read-only variables.
// Ideally, we should do this during AST generation (by converting
// such assignments into expression statements); however, in general
// we may not be able to make the decision until past AST generation,
// that is when the entire program is known.
ASSERT(slot != NULL);
int index = slot->index();
switch (slot->type()) {
case Slot::PARAMETER:
return frame_->ParameterAt(index);
case Slot::LOCAL:
return frame_->LocalAt(index);
case Slot::CONTEXT: {
// Follow the context chain if necessary.
ASSERT(!tmp.is(esi)); // do not overwrite context register
Register context = esi;
int chain_length = scope()->ContextChainLength(slot->var()->scope());
for (int i = 0; i < chain_length; i++) {
// Load the closure.
// (All contexts, even 'with' contexts, have a closure,
// and it is the same for all contexts inside a function.
// There is no need to go to the function context first.)
__ mov(tmp, ContextOperand(context, Context::CLOSURE_INDEX));
// Load the function context (which is the incoming, outer context).
__ mov(tmp, FieldOperand(tmp, JSFunction::kContextOffset));
context = tmp;
}
// We may have a 'with' context now. Get the function context.
// (In fact this mov may never be the needed, since the scope analysis
// may not permit a direct context access in this case and thus we are
// always at a function context. However it is safe to dereference be-
// cause the function context of a function context is itself. Before
// deleting this mov we should try to create a counter-example first,
// though...)
__ mov(tmp, ContextOperand(context, Context::FCONTEXT_INDEX));
return ContextOperand(tmp, index);
}
default:
UNREACHABLE();
return Operand(eax);
}
}
Operand CodeGenerator::ContextSlotOperandCheckExtensions(Slot* slot,
Result tmp,
JumpTarget* slow) {
ASSERT(slot->type() == Slot::CONTEXT);
ASSERT(tmp.is_register());
Register context = esi;
for (Scope* s = scope(); s != slot->var()->scope(); s = s->outer_scope()) {
if (s->num_heap_slots() > 0) {
if (s->calls_eval()) {
// Check that extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
Immediate(0));
slow->Branch(not_equal, not_taken);
}
__ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
context = tmp.reg();
}
}
// Check that last extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX), Immediate(0));
slow->Branch(not_equal, not_taken);
__ mov(tmp.reg(), ContextOperand(context, Context::FCONTEXT_INDEX));
return ContextOperand(tmp.reg(), slot->index());
}
// Emit code to load the value of an expression to the top of the
// frame. If the expression is boolean-valued it may be compiled (or
// partially compiled) into control flow to the control destination.
// If force_control is true, control flow is forced.
void CodeGenerator::LoadCondition(Expression* x,
ControlDestination* dest,
bool force_control) {
ASSERT(!in_spilled_code());
int original_height = frame_->height();
{ CodeGenState new_state(this, dest);
Visit(x);
// If we hit a stack overflow, we may not have actually visited
// the expression. In that case, we ensure that we have a
// valid-looking frame state because we will continue to generate
// code as we unwind the C++ stack.
//
// It's possible to have both a stack overflow and a valid frame
// state (eg, a subexpression overflowed, visiting it returned
// with a dummied frame state, and visiting this expression
// returned with a normal-looking state).
if (HasStackOverflow() &&
!dest->is_used() &&
frame_->height() == original_height) {
dest->Goto(true);
}
}
if (force_control && !dest->is_used()) {
// Convert the TOS value into flow to the control destination.
ToBoolean(dest);
}
ASSERT(!(force_control && !dest->is_used()));
ASSERT(dest->is_used() || frame_->height() == original_height + 1);
}
void CodeGenerator::LoadAndSpill(Expression* expression) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
Load(expression);
frame_->SpillAll();
set_in_spilled_code(true);
}
void CodeGenerator::Load(Expression* expr) {
#ifdef DEBUG
int original_height = frame_->height();
#endif
ASSERT(!in_spilled_code());
JumpTarget true_target;
JumpTarget false_target;
ControlDestination dest(&true_target, &false_target, true);
LoadCondition(expr, &dest, false);
if (dest.false_was_fall_through()) {
// The false target was just bound.
JumpTarget loaded;
frame_->Push(Factory::false_value());
// There may be dangling jumps to the true target.
if (true_target.is_linked()) {
loaded.Jump();
true_target.Bind();
frame_->Push(Factory::true_value());
loaded.Bind();
}
} else if (dest.is_used()) {
// There is true, and possibly false, control flow (with true as
// the fall through).
JumpTarget loaded;
frame_->Push(Factory::true_value());
if (false_target.is_linked()) {
loaded.Jump();
false_target.Bind();
frame_->Push(Factory::false_value());
loaded.Bind();
}
} else {
// We have a valid value on top of the frame, but we still may
// have dangling jumps to the true and false targets from nested
// subexpressions (eg, the left subexpressions of the
// short-circuited boolean operators).
ASSERT(has_valid_frame());
if (true_target.is_linked() || false_target.is_linked()) {
JumpTarget loaded;
loaded.Jump(); // Don't lose the current TOS.
if (true_target.is_linked()) {
true_target.Bind();
frame_->Push(Factory::true_value());
if (false_target.is_linked()) {
loaded.Jump();
}
}
if (false_target.is_linked()) {
false_target.Bind();
frame_->Push(Factory::false_value());
}
loaded.Bind();
}
}
ASSERT(has_valid_frame());
ASSERT(frame_->height() == original_height + 1);
}
void CodeGenerator::LoadGlobal() {
if (in_spilled_code()) {
frame_->EmitPush(GlobalObject());
} else {
Result temp = allocator_->Allocate();
__ mov(temp.reg(), GlobalObject());
frame_->Push(&temp);
}
}
void CodeGenerator::LoadGlobalReceiver() {
Result temp = allocator_->Allocate();
Register reg = temp.reg();
__ mov(reg, GlobalObject());
__ mov(reg, FieldOperand(reg, GlobalObject::kGlobalReceiverOffset));
frame_->Push(&temp);
}
void CodeGenerator::LoadTypeofExpression(Expression* expr) {
// Special handling of identifiers as subexpressions of typeof.
Variable* variable = expr->AsVariableProxy()->AsVariable();
if (variable != NULL && !variable->is_this() && variable->is_global()) {
// For a global variable we build the property reference
// <global>.<variable> and perform a (regular non-contextual) property
// load to make sure we do not get reference errors.
Slot global(variable, Slot::CONTEXT, Context::GLOBAL_INDEX);
Literal key(variable->name());
Property property(&global, &key, RelocInfo::kNoPosition);
Reference ref(this, &property);
ref.GetValue();
} else if (variable != NULL && variable->slot() != NULL) {
// For a variable that rewrites to a slot, we signal it is the immediate
// subexpression of a typeof.
Result result =
LoadFromSlotCheckForArguments(variable->slot(), INSIDE_TYPEOF);
frame()->Push(&result);
} else {
// Anything else can be handled normally.
Load(expr);
}
}
ArgumentsAllocationMode CodeGenerator::ArgumentsMode() {
if (scope()->arguments() == NULL) return NO_ARGUMENTS_ALLOCATION;
ASSERT(scope()->arguments_shadow() != NULL);
// We don't want to do lazy arguments allocation for functions that
// have heap-allocated contexts, because it interfers with the
// uninitialized const tracking in the context objects.
return (scope()->num_heap_slots() > 0)
? EAGER_ARGUMENTS_ALLOCATION
: LAZY_ARGUMENTS_ALLOCATION;
}
Result CodeGenerator::StoreArgumentsObject(bool initial) {
ArgumentsAllocationMode mode = ArgumentsMode();
ASSERT(mode != NO_ARGUMENTS_ALLOCATION);
Comment cmnt(masm_, "[ store arguments object");
if (mode == LAZY_ARGUMENTS_ALLOCATION && initial) {
// When using lazy arguments allocation, we store the hole value
// as a sentinel indicating that the arguments object hasn't been
// allocated yet.
frame_->Push(Factory::the_hole_value());
} else {
ArgumentsAccessStub stub(ArgumentsAccessStub::NEW_OBJECT);
frame_->PushFunction();
frame_->PushReceiverSlotAddress();
frame_->Push(Smi::FromInt(scope()->num_parameters()));
Result result = frame_->CallStub(&stub, 3);
frame_->Push(&result);
}
Variable* arguments = scope()->arguments()->var();
Variable* shadow = scope()->arguments_shadow()->var();
ASSERT(arguments != NULL && arguments->slot() != NULL);
ASSERT(shadow != NULL && shadow->slot() != NULL);
JumpTarget done;
bool skip_arguments = false;
if (mode == LAZY_ARGUMENTS_ALLOCATION && !initial) {
// We have to skip storing into the arguments slot if it has already
// been written to. This can happen if the a function has a local
// variable named 'arguments'.
Result probe = LoadFromSlot(arguments->slot(), NOT_INSIDE_TYPEOF);
if (probe.is_constant()) {
// We have to skip updating the arguments object if it has
// been assigned a proper value.
skip_arguments = !probe.handle()->IsTheHole();
} else {
__ cmp(Operand(probe.reg()), Immediate(Factory::the_hole_value()));
probe.Unuse();
done.Branch(not_equal);
}
}
if (!skip_arguments) {
StoreToSlot(arguments->slot(), NOT_CONST_INIT);
if (mode == LAZY_ARGUMENTS_ALLOCATION) done.Bind();
}
StoreToSlot(shadow->slot(), NOT_CONST_INIT);
return frame_->Pop();
}
//------------------------------------------------------------------------------
// CodeGenerator implementation of variables, lookups, and stores.
Reference::Reference(CodeGenerator* cgen,
Expression* expression,
bool persist_after_get)
: cgen_(cgen),
expression_(expression),
type_(ILLEGAL),
persist_after_get_(persist_after_get) {
cgen->LoadReference(this);
}
Reference::~Reference() {
ASSERT(is_unloaded() || is_illegal());
}
void CodeGenerator::LoadReference(Reference* ref) {
// References are loaded from both spilled and unspilled code. Set the
// state to unspilled to allow that (and explicitly spill after
// construction at the construction sites).
bool was_in_spilled_code = in_spilled_code_;
in_spilled_code_ = false;
Comment cmnt(masm_, "[ LoadReference");
Expression* e = ref->expression();
Property* property = e->AsProperty();
Variable* var = e->AsVariableProxy()->AsVariable();
if (property != NULL) {
// The expression is either a property or a variable proxy that rewrites
// to a property.
Load(property->obj());
if (property->key()->IsPropertyName()) {
ref->set_type(Reference::NAMED);
} else {
Load(property->key());
ref->set_type(Reference::KEYED);
}
} else if (var != NULL) {
// The expression is a variable proxy that does not rewrite to a
// property. Global variables are treated as named property references.
if (var->is_global()) {
// If eax is free, the register allocator prefers it. Thus the code
// generator will load the global object into eax, which is where
// LoadIC wants it. Most uses of Reference call LoadIC directly
// after the reference is created.
frame_->Spill(eax);
LoadGlobal();
ref->set_type(Reference::NAMED);
} else {
ASSERT(var->slot() != NULL);
ref->set_type(Reference::SLOT);
}
} else {
// Anything else is a runtime error.
Load(e);
frame_->CallRuntime(Runtime::kThrowReferenceError, 1);
}
in_spilled_code_ = was_in_spilled_code;
}
void CodeGenerator::UnloadReference(Reference* ref) {
// Pop a reference from the stack while preserving TOS.
Comment cmnt(masm_, "[ UnloadReference");
frame_->Nip(ref->size());
ref->set_unloaded();
}
// ECMA-262, section 9.2, page 30: ToBoolean(). Pop the top of stack and
// convert it to a boolean in the condition code register or jump to
// 'false_target'/'true_target' as appropriate.
void CodeGenerator::ToBoolean(ControlDestination* dest) {
Comment cmnt(masm_, "[ ToBoolean");
// The value to convert should be popped from the frame.
Result value = frame_->Pop();
value.ToRegister();
if (value.is_number()) {
Comment cmnt(masm_, "ONLY_NUMBER");
// Fast case if NumberInfo indicates only numbers.
if (FLAG_debug_code) {
__ AbortIfNotNumber(value.reg(), "ToBoolean operand is not a number.");
}
// Smi => false iff zero.
ASSERT(kSmiTag == 0);
__ test(value.reg(), Operand(value.reg()));
dest->false_target()->Branch(zero);
__ test(value.reg(), Immediate(kSmiTagMask));
dest->true_target()->Branch(zero);
__ fldz();
__ fld_d(FieldOperand(value.reg(), HeapNumber::kValueOffset));
__ FCmp();
value.Unuse();
dest->Split(not_zero);
} else {
// Fast case checks.
// 'false' => false.
__ cmp(value.reg(), Factory::false_value());
dest->false_target()->Branch(equal);
// 'true' => true.
__ cmp(value.reg(), Factory::true_value());
dest->true_target()->Branch(equal);
// 'undefined' => false.
__ cmp(value.reg(), Factory::undefined_value());
dest->false_target()->Branch(equal);
// Smi => false iff zero.
ASSERT(kSmiTag == 0);
__ test(value.reg(), Operand(value.reg()));
dest->false_target()->Branch(zero);
__ test(value.reg(), Immediate(kSmiTagMask));
dest->true_target()->Branch(zero);
// Call the stub for all other cases.
frame_->Push(&value); // Undo the Pop() from above.
ToBooleanStub stub;
Result temp = frame_->CallStub(&stub, 1);
// Convert the result to a condition code.
__ test(temp.reg(), Operand(temp.reg()));
temp.Unuse();
dest->Split(not_equal);
}
}
class FloatingPointHelper : public AllStatic {
public:
enum ArgLocation {
ARGS_ON_STACK,
ARGS_IN_REGISTERS
};
// Code pattern for loading a floating point value. Input value must
// be either a smi or a heap number object (fp value). Requirements:
// operand in register number. Returns operand as floating point number
// on FPU stack.
static void LoadFloatOperand(MacroAssembler* masm, Register number);
// Code pattern for loading floating point values. Input values must
// be either smi or heap number objects (fp values). Requirements:
// operand_1 on TOS+1 or in edx, operand_2 on TOS+2 or in eax.
// Returns operands as floating point numbers on FPU stack.
static void LoadFloatOperands(MacroAssembler* masm,
Register scratch,
ArgLocation arg_location = ARGS_ON_STACK);
// Similar to LoadFloatOperand but assumes that both operands are smis.
// Expects operands in edx, eax.
static void LoadFloatSmis(MacroAssembler* masm, Register scratch);
// Test if operands are smi or number objects (fp). Requirements:
// operand_1 in eax, operand_2 in edx; falls through on float
// operands, jumps to the non_float label otherwise.
static void CheckFloatOperands(MacroAssembler* masm,
Label* non_float,
Register scratch);
// Takes the operands in edx and eax and loads them as integers in eax
// and ecx.
static void LoadAsIntegers(MacroAssembler* masm,
bool use_sse3,
Label* operand_conversion_failure);
// Test if operands are smis or heap numbers and load them
// into xmm0 and xmm1 if they are. Operands are in edx and eax.
// Leaves operands unchanged.
static void LoadSSE2Operands(MacroAssembler* masm);
// Test if operands are numbers (smi or HeapNumber objects), and load
// them into xmm0 and xmm1 if they are. Jump to label not_numbers if
// either operand is not a number. Operands are in edx and eax.
// Leaves operands unchanged.
static void LoadSSE2Operands(MacroAssembler* masm, Label* not_numbers);
// Similar to LoadSSE2Operands but assumes that both operands are smis.
// Expects operands in edx, eax.
static void LoadSSE2Smis(MacroAssembler* masm, Register scratch);
};
const char* GenericBinaryOpStub::GetName() {
if (name_ != NULL) return name_;
const int kMaxNameLength = 100;
name_ = Bootstrapper::AllocateAutoDeletedArray(kMaxNameLength);
if (name_ == NULL) return "OOM";
const char* op_name = Token::Name(op_);
const char* overwrite_name;
switch (mode_) {
case NO_OVERWRITE: overwrite_name = "Alloc"; break;
case OVERWRITE_RIGHT: overwrite_name = "OverwriteRight"; break;
case OVERWRITE_LEFT: overwrite_name = "OverwriteLeft"; break;
default: overwrite_name = "UnknownOverwrite"; break;
}
OS::SNPrintF(Vector<char>(name_, kMaxNameLength),
"GenericBinaryOpStub_%s_%s%s_%s%s_%s",
op_name,
overwrite_name,
(flags_ & NO_SMI_CODE_IN_STUB) ? "_NoSmiInStub" : "",
args_in_registers_ ? "RegArgs" : "StackArgs",
args_reversed_ ? "_R" : "",
NumberInfo::ToString(operands_type_));
return name_;
}
// Call the specialized stub for a binary operation.
class DeferredInlineBinaryOperation: public DeferredCode {
public:
DeferredInlineBinaryOperation(Token::Value op,
Register dst,
Register left,
Register right,
OverwriteMode mode)
: op_(op), dst_(dst), left_(left), right_(right), mode_(mode) {
set_comment("[ DeferredInlineBinaryOperation");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Register left_;
Register right_;
OverwriteMode mode_;
};
void DeferredInlineBinaryOperation::Generate() {
Label done;
if (CpuFeatures::IsSupported(SSE2) && ((op_ == Token::ADD) ||
(op_ ==Token::SUB) ||
(op_ == Token::MUL) ||
(op_ == Token::DIV))) {
CpuFeatures::Scope use_sse2(SSE2);
Label call_runtime, after_alloc_failure;
Label left_smi, right_smi, load_right, do_op;
__ test(left_, Immediate(kSmiTagMask));
__ j(zero, &left_smi);
__ cmp(FieldOperand(left_, HeapObject::kMapOffset),
Factory::heap_number_map());
__ j(not_equal, &call_runtime);
__ movdbl(xmm0, FieldOperand(left_, HeapNumber::kValueOffset));
if (mode_ == OVERWRITE_LEFT) {
__ mov(dst_, left_);
}
__ jmp(&load_right);
__ bind(&left_smi);
__ SmiUntag(left_);
__ cvtsi2sd(xmm0, Operand(left_));
__ SmiTag(left_);
if (mode_ == OVERWRITE_LEFT) {
Label alloc_failure;
__ push(left_);
__ AllocateHeapNumber(dst_, left_, no_reg, &after_alloc_failure);
__ pop(left_);
}
__ bind(&load_right);
__ test(right_, Immediate(kSmiTagMask));
__ j(zero, &right_smi);
__ cmp(FieldOperand(right_, HeapObject::kMapOffset),
Factory::heap_number_map());
__ j(not_equal, &call_runtime);
__ movdbl(xmm1, FieldOperand(right_, HeapNumber::kValueOffset));
if (mode_ == OVERWRITE_RIGHT) {
__ mov(dst_, right_);
} else if (mode_ == NO_OVERWRITE) {
Label alloc_failure;
__ push(left_);
__ AllocateHeapNumber(dst_, left_, no_reg, &after_alloc_failure);
__ pop(left_);
}
__ jmp(&do_op);
__ bind(&right_smi);
__ SmiUntag(right_);
__ cvtsi2sd(xmm1, Operand(right_));
__ SmiTag(right_);
if (mode_ == OVERWRITE_RIGHT || mode_ == NO_OVERWRITE) {
Label alloc_failure;
__ push(left_);
__ AllocateHeapNumber(dst_, left_, no_reg, &after_alloc_failure);
__ pop(left_);
}
__ bind(&do_op);
switch (op_) {
case Token::ADD: __ addsd(xmm0, xmm1); break;
case Token::SUB: __ subsd(xmm0, xmm1); break;
case Token::MUL: __ mulsd(xmm0, xmm1); break;
case Token::DIV: __ divsd(xmm0, xmm1); break;
default: UNREACHABLE();
}
__ movdbl(FieldOperand(dst_, HeapNumber::kValueOffset), xmm0);
__ jmp(&done);
__ bind(&after_alloc_failure);
__ pop(left_);
__ bind(&call_runtime);
}
GenericBinaryOpStub stub(op_, mode_, NO_SMI_CODE_IN_STUB);
stub.GenerateCall(masm_, left_, right_);
if (!dst_.is(eax)) __ mov(dst_, eax);
__ bind(&done);
}
void CodeGenerator::GenericBinaryOperation(Token::Value op,
StaticType* type,
OverwriteMode overwrite_mode) {
Comment cmnt(masm_, "[ BinaryOperation");
Comment cmnt_token(masm_, Token::String(op));
if (op == Token::COMMA) {
// Simply discard left value.
frame_->Nip(1);
return;
}
Result right = frame_->Pop();
Result left = frame_->Pop();
if (op == Token::ADD) {
bool left_is_string = left.is_constant() && left.handle()->IsString();
bool right_is_string = right.is_constant() && right.handle()->IsString();
if (left_is_string || right_is_string) {
frame_->Push(&left);
frame_->Push(&right);
Result answer;
if (left_is_string) {
if (right_is_string) {
// TODO(lrn): if both are constant strings
// -- do a compile time cons, if allocation during codegen is allowed.
answer = frame_->CallRuntime(Runtime::kStringAdd, 2);
} else {
answer =
frame_->InvokeBuiltin(Builtins::STRING_ADD_LEFT, CALL_FUNCTION, 2);
}
} else if (right_is_string) {
answer =
frame_->InvokeBuiltin(Builtins::STRING_ADD_RIGHT, CALL_FUNCTION, 2);
}
frame_->Push(&answer);
return;
}
// Neither operand is known to be a string.
}
bool left_is_smi_constant = left.is_constant() && left.handle()->IsSmi();
bool left_is_non_smi_constant = left.is_constant() && !left.handle()->IsSmi();
bool right_is_smi_constant = right.is_constant() && right.handle()->IsSmi();
bool right_is_non_smi_constant =
right.is_constant() && !right.handle()->IsSmi();
if (left_is_smi_constant && right_is_smi_constant) {
// Compute the constant result at compile time, and leave it on the frame.
int left_int = Smi::cast(*left.handle())->value();
int right_int = Smi::cast(*right.handle())->value();
if (FoldConstantSmis(op, left_int, right_int)) return;
}
// Get number type of left and right sub-expressions.
NumberInfo::Type operands_type =
NumberInfo::Combine(left.number_info(), right.number_info());
Result answer;
if (left_is_non_smi_constant || right_is_non_smi_constant) {
// Go straight to the slow case, with no smi code.
GenericBinaryOpStub stub(op,
overwrite_mode,
NO_SMI_CODE_IN_STUB,
operands_type);
answer = stub.GenerateCall(masm_, frame_, &left, &right);
} else if (right_is_smi_constant) {
answer = ConstantSmiBinaryOperation(op, &left, right.handle(),
type, false, overwrite_mode);
} else if (left_is_smi_constant) {
answer = ConstantSmiBinaryOperation(op, &right, left.handle(),
type, true, overwrite_mode);
} else {
// Set the flags based on the operation, type and loop nesting level.
// Bit operations always assume they likely operate on Smis. Still only
// generate the inline Smi check code if this operation is part of a loop.
// For all other operations only inline the Smi check code for likely smis
// if the operation is part of a loop.
if (loop_nesting() > 0 && (Token::IsBitOp(op) || type->IsLikelySmi())) {
answer = LikelySmiBinaryOperation(op, &left, &right, overwrite_mode);
} else {
GenericBinaryOpStub stub(op,
overwrite_mode,
NO_GENERIC_BINARY_FLAGS,
operands_type);
answer = stub.GenerateCall(masm_, frame_, &left, &right);
}
}
// Set NumberInfo of result according to the operation performed.
// Rely on the fact that smis have a 31 bit payload on ia32.
ASSERT(kSmiValueSize == 31);
NumberInfo::Type result_type = NumberInfo::kUnknown;
switch (op) {
case Token::COMMA:
result_type = right.number_info();
break;
case Token::OR:
case Token::AND:
// Result type can be either of the two input types.
result_type = operands_type;
break;
case Token::BIT_OR:
case Token::BIT_XOR:
case Token::BIT_AND:
// Result is always a number. Smi property of inputs is preserved.
result_type = (operands_type == NumberInfo::kSmi)
? NumberInfo::kSmi
: NumberInfo::kNumber;
break;
case Token::SAR:
// Result is a smi if we shift by a constant >= 1, otherwise a number.
result_type = (right.is_constant() && right.handle()->IsSmi()
&& Smi::cast(*right.handle())->value() >= 1)
? NumberInfo::kSmi
: NumberInfo::kNumber;
break;
case Token::SHR:
// Result is a smi if we shift by a constant >= 2, otherwise a number.
result_type = (right.is_constant() && right.handle()->IsSmi()
&& Smi::cast(*right.handle())->value() >= 2)
? NumberInfo::kSmi
: NumberInfo::kNumber;
break;
case Token::ADD:
// Result could be a string or a number. Check types of inputs.
result_type = NumberInfo::IsNumber(operands_type)
? NumberInfo::kNumber
: NumberInfo::kUnknown;
break;
case Token::SHL:
case Token::SUB:
case Token::MUL:
case Token::DIV:
case Token::MOD:
// Result is always a number.
result_type = NumberInfo::kNumber;
break;
default:
UNREACHABLE();
}
answer.set_number_info(result_type);
frame_->Push(&answer);
}
bool CodeGenerator::FoldConstantSmis(Token::Value op, int left, int right) {
Object* answer_object = Heap::undefined_value();
switch (op) {
case Token::ADD:
if (Smi::IsValid(left + right)) {
answer_object = Smi::FromInt(left + right);
}
break;
case Token::SUB:
if (Smi::IsValid(left - right)) {
answer_object = Smi::FromInt(left - right);
}
break;
case Token::MUL: {
double answer = static_cast<double>(left) * right;
if (answer >= Smi::kMinValue && answer <= Smi::kMaxValue) {
// If the product is zero and the non-zero factor is negative,
// the spec requires us to return floating point negative zero.
if (answer != 0 || (left >= 0 && right >= 0)) {
answer_object = Smi::FromInt(static_cast<int>(answer));
}
}
}
break;
case Token::DIV:
case Token::MOD:
break;
case Token::BIT_OR:
answer_object = Smi::FromInt(left | right);
break;
case Token::BIT_AND:
answer_object = Smi::FromInt(left & right);
break;
case Token::BIT_XOR:
answer_object = Smi::FromInt(left ^ right);
break;
case Token::SHL: {
int shift_amount = right & 0x1F;
if (Smi::IsValid(left << shift_amount)) {
answer_object = Smi::FromInt(left << shift_amount);
}
break;
}
case Token::SHR: {
int shift_amount = right & 0x1F;
unsigned int unsigned_left = left;
unsigned_left >>= shift_amount;
if (unsigned_left <= static_cast<unsigned int>(Smi::kMaxValue)) {
answer_object = Smi::FromInt(unsigned_left);
}
break;
}
case Token::SAR: {
int shift_amount = right & 0x1F;
unsigned int unsigned_left = left;
if (left < 0) {
// Perform arithmetic shift of a negative number by
// complementing number, logical shifting, complementing again.
unsigned_left = ~unsigned_left;
unsigned_left >>= shift_amount;
unsigned_left = ~unsigned_left;
} else {
unsigned_left >>= shift_amount;
}
ASSERT(Smi::IsValid(unsigned_left)); // Converted to signed.
answer_object = Smi::FromInt(unsigned_left); // Converted to signed.
break;
}
default:
UNREACHABLE();
break;
}
if (answer_object == Heap::undefined_value()) {
return false;
}
frame_->Push(Handle<Object>(answer_object));
return true;
}
// Implements a binary operation using a deferred code object and some
// inline code to operate on smis quickly.
Result CodeGenerator::LikelySmiBinaryOperation(Token::Value op,
Result* left,
Result* right,
OverwriteMode overwrite_mode) {
Result answer;
// Special handling of div and mod because they use fixed registers.
if (op == Token::DIV || op == Token::MOD) {
// We need eax as the quotient register, edx as the remainder
// register, neither left nor right in eax or edx, and left copied
// to eax.
Result quotient;
Result remainder;
bool left_is_in_eax = false;
// Step 1: get eax for quotient.
if ((left->is_register() && left->reg().is(eax)) ||
(right->is_register() && right->reg().is(eax))) {
// One or both is in eax. Use a fresh non-edx register for
// them.
Result fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
if (fresh.reg().is(edx)) {
remainder = fresh;
fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
}
if (left->is_register() && left->reg().is(eax)) {
quotient = *left;
*left = fresh;
left_is_in_eax = true;
}
if (right->is_register() && right->reg().is(eax)) {
quotient = *right;
*right = fresh;
}
__ mov(fresh.reg(), eax);
} else {
// Neither left nor right is in eax.
quotient = allocator_->Allocate(eax);
}
ASSERT(quotient.is_register() && quotient.reg().is(eax));
ASSERT(!(left->is_register() && left->reg().is(eax)));
ASSERT(!(right->is_register() && right->reg().is(eax)));
// Step 2: get edx for remainder if necessary.
if (!remainder.is_valid()) {
if ((left->is_register() && left->reg().is(edx)) ||
(right->is_register() && right->reg().is(edx))) {
Result fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
if (left->is_register() && left->reg().is(edx)) {
remainder = *left;
*left = fresh;
}
if (right->is_register() && right->reg().is(edx)) {
remainder = *right;
*right = fresh;
}
__ mov(fresh.reg(), edx);
} else {
// Neither left nor right is in edx.
remainder = allocator_->Allocate(edx);
}
}
ASSERT(remainder.is_register() && remainder.reg().is(edx));
ASSERT(!(left->is_register() && left->reg().is(edx)));
ASSERT(!(right->is_register() && right->reg().is(edx)));
left->ToRegister();
right->ToRegister();
frame_->Spill(eax);
frame_->Spill(edx);
// Check that left and right are smi tagged.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
(op == Token::DIV) ? eax : edx,
left->reg(),
right->reg(),
overwrite_mode);
if (left->reg().is(right->reg())) {
__ test(left->reg(), Immediate(kSmiTagMask));
} else {
// Use the quotient register as a scratch for the tag check.
if (!left_is_in_eax) __ mov(eax, left->reg());
left_is_in_eax = false; // About to destroy the value in eax.
__ or_(eax, Operand(right->reg()));
ASSERT(kSmiTag == 0); // Adjust test if not the case.
__ test(eax, Immediate(kSmiTagMask));
}
deferred->Branch(not_zero);
if (!left_is_in_eax) __ mov(eax, left->reg());
// Sign extend eax into edx:eax.
__ cdq();
// Check for 0 divisor.
__ test(right->reg(), Operand(right->reg()));
deferred->Branch(zero);
// Divide edx:eax by the right operand.
__ idiv(right->reg());
// Complete the operation.
if (op == Token::DIV) {
// Check for negative zero result. If result is zero, and divisor
// is negative, return a floating point negative zero. The
// virtual frame is unchanged in this block, so local control flow
// can use a Label rather than a JumpTarget.
Label non_zero_result;
__ test(left->reg(), Operand(left->reg()));
__ j(not_zero, &non_zero_result);
__ test(right->reg(), Operand(right->reg()));
deferred->Branch(negative);
__ bind(&non_zero_result);
// Check for the corner case of dividing the most negative smi by
// -1. We cannot use the overflow flag, since it is not set by
// idiv instruction.
ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ cmp(eax, 0x40000000);
deferred->Branch(equal);
// Check that the remainder is zero.
__ test(edx, Operand(edx));
deferred->Branch(not_zero);
// Tag the result and store it in the quotient register.
__ SmiTag(eax);
deferred->BindExit();
left->Unuse();
right->Unuse();
answer = quotient;
} else {
ASSERT(op == Token::MOD);
// Check for a negative zero result. If the result is zero, and
// the dividend is negative, return a floating point negative
// zero. The frame is unchanged in this block, so local control
// flow can use a Label rather than a JumpTarget.
Label non_zero_result;
__ test(edx, Operand(edx));
__ j(not_zero, &non_zero_result, taken);
__ test(left->reg(), Operand(left->reg()));
deferred->Branch(negative);
__ bind(&non_zero_result);
deferred->BindExit();
left->Unuse();
right->Unuse();
answer = remainder;
}
ASSERT(answer.is_valid());
return answer;
}
// Special handling of shift operations because they use fixed
// registers.
if (op == Token::SHL || op == Token::SHR || op == Token::SAR) {
// Move left out of ecx if necessary.
if (left->is_register() && left->reg().is(ecx)) {
*left = allocator_->Allocate();
ASSERT(left->is_valid());
__ mov(left->reg(), ecx);
}
right->ToRegister(ecx);
left->ToRegister();
ASSERT(left->is_register() && !left->reg().is(ecx));
ASSERT(right->is_register() && right->reg().is(ecx));
// We will modify right, it must be spilled.
frame_->Spill(ecx);
// Use a fresh answer register to avoid spilling the left operand.
answer = allocator_->Allocate();
ASSERT(answer.is_valid());
// Check that both operands are smis using the answer register as a
// temporary.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
answer.reg(),
left->reg(),
ecx,
overwrite_mode);
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(ecx));
__ test(answer.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
// Untag both operands.
__ mov(answer.reg(), left->reg());
__ SmiUntag(answer.reg());
__ SmiUntag(ecx);
// Perform the operation.
switch (op) {
case Token::SAR:
__ sar_cl(answer.reg());
// No checks of result necessary
break;
case Token::SHR: {
Label result_ok;
__ shr_cl(answer.reg());
// Check that the *unsigned* result fits in a smi. Neither of
// the two high-order bits can be set:
// * 0x80000000: high bit would be lost when smi tagging.
// * 0x40000000: this number would convert to negative when smi
// tagging.
// These two cases can only happen with shifts by 0 or 1 when
// handed a valid smi. If the answer cannot be represented by a
// smi, restore the left and right arguments, and jump to slow
// case. The low bit of the left argument may be lost, but only
// in a case where it is dropped anyway.
__ test(answer.reg(), Immediate(0xc0000000));
__ j(zero, &result_ok);
__ SmiTag(ecx);
deferred->Jump();
__ bind(&result_ok);
break;
}
case Token::SHL: {
Label result_ok;
__ shl_cl(answer.reg());
// Check that the *signed* result fits in a smi.
__ cmp(answer.reg(), 0xc0000000);
__ j(positive, &result_ok);
__ SmiTag(ecx);
deferred->Jump();
__ bind(&result_ok);
break;
}
default:
UNREACHABLE();
}
// Smi-tag the result in answer.
__ SmiTag(answer.reg());
deferred->BindExit();
left->Unuse();
right->Unuse();
ASSERT(answer.is_valid());
return answer;
}
// Handle the other binary operations.
left->ToRegister();
right->ToRegister();
// A newly allocated register answer is used to hold the answer. The
// registers containing left and right are not modified so they don't
// need to be spilled in the fast case.
answer = allocator_->Allocate();
ASSERT(answer.is_valid());
// Perform the smi tag check.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
answer.reg(),
left->reg(),
right->reg(),
overwrite_mode);
if (left->reg().is(right->reg())) {
__ test(left->reg(), Immediate(kSmiTagMask));
} else {
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(right->reg()));
ASSERT(kSmiTag == 0); // Adjust test if not the case.
__ test(answer.reg(), Immediate(kSmiTagMask));
}
deferred->Branch(not_zero);
__ mov(answer.reg(), left->reg());
switch (op) {
case Token::ADD:
__ add(answer.reg(), Operand(right->reg()));
deferred->Branch(overflow);
break;
case Token::SUB:
__ sub(answer.reg(), Operand(right->reg()));
deferred->Branch(overflow);
break;
case Token::MUL: {
// If the smi tag is 0 we can just leave the tag on one operand.
ASSERT(kSmiTag == 0); // Adjust code below if not the case.
// Remove smi tag from the left operand (but keep sign).
// Left-hand operand has been copied into answer.
__ SmiUntag(answer.reg());
// Do multiplication of smis, leaving result in answer.
__ imul(answer.reg(), Operand(right->reg()));
// Go slow on overflows.
deferred->Branch(overflow);
// Check for negative zero result. If product is zero, and one
// argument is negative, go to slow case. The frame is unchanged
// in this block, so local control flow can use a Label rather
// than a JumpTarget.
Label non_zero_result;
__ test(answer.reg(), Operand(answer.reg()));
__ j(not_zero, &non_zero_result, taken);
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(right->reg()));
deferred->Branch(negative);
__ xor_(answer.reg(), Operand(answer.reg())); // Positive 0 is correct.
__ bind(&non_zero_result);
break;
}
case Token::BIT_OR:
__ or_(answer.reg(), Operand(right->reg()));
break;
case Token::BIT_AND:
__ and_(answer.reg(), Operand(right->reg()));
break;
case Token::BIT_XOR:
__ xor_(answer.reg(), Operand(right->reg()));
break;
default:
UNREACHABLE();
break;
}
deferred->BindExit();
left->Unuse();
right->Unuse();
ASSERT(answer.is_valid());
return answer;
}
// Call the appropriate binary operation stub to compute src op value
// and leave the result in dst.
class DeferredInlineSmiOperation: public DeferredCode {
public:
DeferredInlineSmiOperation(Token::Value op,
Register dst,
Register src,
Smi* value,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
src_(src),
value_(value),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiOperation");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Register src_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiOperation::Generate() {
// For mod we don't generate all the Smi code inline.
GenericBinaryOpStub stub(
op_,
overwrite_mode_,
(op_ == Token::MOD) ? NO_GENERIC_BINARY_FLAGS : NO_SMI_CODE_IN_STUB);
stub.GenerateCall(masm_, src_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// Call the appropriate binary operation stub to compute value op src
// and leave the result in dst.
class DeferredInlineSmiOperationReversed: public DeferredCode {
public:
DeferredInlineSmiOperationReversed(Token::Value op,
Register dst,
Smi* value,
Register src,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
value_(value),
src_(src),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiOperationReversed");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Smi* value_;
Register src_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiOperationReversed::Generate() {
GenericBinaryOpStub igostub(op_, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, value_, src_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of src + value is in dst. It either overflowed or was not
// smi tagged. Undo the speculative addition and call the appropriate
// specialized stub for add. The result is left in dst.
class DeferredInlineSmiAdd: public DeferredCode {
public:
DeferredInlineSmiAdd(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiAdd");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiAdd::Generate() {
// Undo the optimistic add operation and call the shared stub.
__ sub(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, dst_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of value + src is in dst. It either overflowed or was not
// smi tagged. Undo the speculative addition and call the appropriate
// specialized stub for add. The result is left in dst.
class DeferredInlineSmiAddReversed: public DeferredCode {
public:
DeferredInlineSmiAddReversed(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiAddReversed");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiAddReversed::Generate() {
// Undo the optimistic add operation and call the shared stub.
__ sub(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, value_, dst_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of src - value is in dst. It either overflowed or was not
// smi tagged. Undo the speculative subtraction and call the
// appropriate specialized stub for subtract. The result is left in
// dst.
class DeferredInlineSmiSub: public DeferredCode {
public:
DeferredInlineSmiSub(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiSub");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiSub::Generate() {
// Undo the optimistic sub operation and call the shared stub.
__ add(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::SUB, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, dst_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
Result CodeGenerator::ConstantSmiBinaryOperation(Token::Value op,
Result* operand,
Handle<Object> value,
StaticType* type,
bool reversed,
OverwriteMode overwrite_mode) {
// NOTE: This is an attempt to inline (a bit) more of the code for
// some possible smi operations (like + and -) when (at least) one
// of the operands is a constant smi.
// Consumes the argument "operand".
// TODO(199): Optimize some special cases of operations involving a
// smi literal (multiply by 2, shift by 0, etc.).
if (IsUnsafeSmi(value)) {
Result unsafe_operand(value);
if (reversed) {
return LikelySmiBinaryOperation(op, &unsafe_operand, operand,
overwrite_mode);
} else {
return LikelySmiBinaryOperation(op, operand, &unsafe_operand,
overwrite_mode);
}
}
// Get the literal value.
Smi* smi_value = Smi::cast(*value);
int int_value = smi_value->value();
Result answer;
switch (op) {
case Token::ADD: {
operand->ToRegister();
frame_->Spill(operand->reg());
// Optimistically add. Call the specialized add stub if the
// result is not a smi or overflows.
DeferredCode* deferred = NULL;
if (reversed) {
deferred = new DeferredInlineSmiAddReversed(operand->reg(),
smi_value,
overwrite_mode);
} else {
deferred = new DeferredInlineSmiAdd(operand->reg(),
smi_value,
overwrite_mode);
}
__ add(Operand(operand->reg()), Immediate(value));
deferred->Branch(overflow);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
answer = *operand;
break;
}
case Token::SUB: {
DeferredCode* deferred = NULL;
if (reversed) {
// The reversed case is only hit when the right operand is not a
// constant.
ASSERT(operand->is_register());
answer = allocator()->Allocate();
ASSERT(answer.is_valid());
__ Set(answer.reg(), Immediate(value));
deferred = new DeferredInlineSmiOperationReversed(op,
answer.reg(),
smi_value,
operand->reg(),
overwrite_mode);
__ sub(answer.reg(), Operand(operand->reg()));
} else {
operand->ToRegister();
frame_->Spill(operand->reg());
answer = *operand;
deferred = new DeferredInlineSmiSub(operand->reg(),
smi_value,
overwrite_mode);
__ sub(Operand(operand->reg()), Immediate(value));
}
deferred->Branch(overflow);
__ test(answer.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
operand->Unuse();
break;
}
case Token::SAR:
if (reversed) {
Result constant_operand(value);
answer = LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
if (shift_value > 0) {
__ sar(operand->reg(), shift_value);
__ and_(operand->reg(), ~kSmiTagMask);
}
deferred->BindExit();
answer = *operand;
}
break;
case Token::SHR:
if (reversed) {
Result constant_operand(value);
answer = LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
answer = allocator()->Allocate();
ASSERT(answer.is_valid());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
answer.reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
__ mov(answer.reg(), operand->reg());
__ SmiUntag(answer.reg());
__ shr(answer.reg(), shift_value);
// A negative Smi shifted right two is in the positive Smi range.
if (shift_value < 2) {
__ test(answer.reg(), Immediate(0xc0000000));
deferred->Branch(not_zero);
}
operand->Unuse();
__ SmiTag(answer.reg());
deferred->BindExit();
}
break;
case Token::SHL:
if (reversed) {
Result right;
Result right_copy_in_ecx;
// Make sure to get a copy of the right operand into ecx. This
// allows us to modify it without having to restore it in the
// deferred code.
operand->ToRegister();
if (operand->reg().is(ecx)) {
right = allocator()->Allocate();
__ mov(right.reg(), ecx);
frame_->Spill(ecx);
right_copy_in_ecx = *operand;
} else {
right_copy_in_ecx = allocator()->Allocate(ecx);
__ mov(ecx, operand->reg());
right = *operand;
}
operand->Unuse();
answer = allocator()->Allocate();
DeferredInlineSmiOperationReversed* deferred =
new DeferredInlineSmiOperationReversed(op,
answer.reg(),
smi_value,
right.reg(),
overwrite_mode);
__ mov(answer.reg(), Immediate(int_value));
__ sar(ecx, kSmiTagSize);
deferred->Branch(carry);
__ shl_cl(answer.reg());
__ cmp(answer.reg(), 0xc0000000);
deferred->Branch(sign);
__ SmiTag(answer.reg());
deferred->BindExit();
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
if (shift_value == 0) {
// Spill operand so it can be overwritten in the slow case.
frame_->Spill(operand->reg());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
answer = *operand;
} else {
// Use a fresh temporary for nonzero shift values.
answer = allocator()->Allocate();
ASSERT(answer.is_valid());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
answer.reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
__ mov(answer.reg(), operand->reg());
ASSERT(kSmiTag == 0); // adjust code if not the case
// We do no shifts, only the Smi conversion, if shift_value is 1.
if (shift_value > 1) {
__ shl(answer.reg(), shift_value - 1);
}
// Convert int result to Smi, checking that it is in int range.
ASSERT(kSmiTagSize == 1); // adjust code if not the case
__ add(answer.reg(), Operand(answer.reg()));
deferred->Branch(overflow);
deferred->BindExit();
operand->Unuse();
}
}
break;
case Token::BIT_OR:
case Token::BIT_XOR:
case Token::BIT_AND: {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredCode* deferred = NULL;
if (reversed) {
deferred = new DeferredInlineSmiOperationReversed(op,
operand->reg(),
smi_value,
operand->reg(),
overwrite_mode);
} else {
deferred = new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
}
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
if (op == Token::BIT_AND) {
__ and_(Operand(operand->reg()), Immediate(value));
} else if (op == Token::BIT_XOR) {
if (int_value != 0) {
__ xor_(Operand(operand->reg()), Immediate(value));
}
} else {
ASSERT(op == Token::BIT_OR);
if (int_value != 0) {
__ or_(Operand(operand->reg()), Immediate(value));
}
}
deferred->BindExit();
answer = *operand;
break;
}
case Token::DIV:
if (!reversed && int_value == 2) {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
// Check that lowest log2(value) bits of operand are zero, and test
// smi tag at the same time.
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(1, kSmiTagSize);
__ test(operand->reg(), Immediate(3));
deferred->Branch(not_zero); // Branch if non-smi or odd smi.
__ sar(operand->reg(), 1);
deferred->BindExit();
answer = *operand;
} else {
// Cannot fall through MOD to default case, so we duplicate the
// default case here.
Result constant_operand(value);
if (reversed) {
answer = LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
answer = LikelySmiBinaryOperation(op, operand, &constant_operand,
overwrite_mode);
}
}
break;
// Generate inline code for mod of powers of 2 and negative powers of 2.
case Token::MOD:
if (!reversed &&
int_value != 0 &&
(IsPowerOf2(int_value) || IsPowerOf2(-int_value))) {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredCode* deferred = new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
// Check for negative or non-Smi left hand side.
__ test(operand->reg(), Immediate(kSmiTagMask | 0x80000000));
deferred->Branch(not_zero);
if (int_value < 0) int_value = -int_value;
if (int_value == 1) {
__ mov(operand->reg(), Immediate(Smi::FromInt(0)));
} else {
__ and_(operand->reg(), (int_value << kSmiTagSize) - 1);
}
deferred->BindExit();
answer = *operand;
break;
}
// Fall through if we did not find a power of 2 on the right hand side!
default: {
Result constant_operand(value);
if (reversed) {
answer = LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
answer = LikelySmiBinaryOperation(op, operand, &constant_operand,
overwrite_mode);
}
break;
}
}
ASSERT(answer.is_valid());
return answer;
}
static bool CouldBeNaN(const Result& result) {
if (!result.is_constant()) return true;
if (!result.handle()->IsHeapNumber()) return false;
return isnan(HeapNumber::cast(*result.handle())->value());
}
void CodeGenerator::Comparison(AstNode* node,
Condition cc,
bool strict,
ControlDestination* dest) {
// Strict only makes sense for equality comparisons.
ASSERT(!strict || cc == equal);
Result left_side;
Result right_side;
// Implement '>' and '<=' by reversal to obtain ECMA-262 conversion order.
if (cc == greater || cc == less_equal) {
cc = ReverseCondition(cc);
left_side = frame_->Pop();
right_side = frame_->Pop();
} else {
right_side = frame_->Pop();
left_side = frame_->Pop();
}
ASSERT(cc == less || cc == equal || cc == greater_equal);
// If either side is a constant of some sort, we can probably optimize the
// comparison.
bool left_side_constant_smi = false;
bool left_side_constant_null = false;
bool left_side_constant_1_char_string = false;
if (left_side.is_constant()) {
left_side_constant_smi = left_side.handle()->IsSmi();
left_side_constant_null = left_side.handle()->IsNull();
left_side_constant_1_char_string =
(left_side.handle()->IsString() &&
(String::cast(*left_side.handle())->length() == 1));
}
bool right_side_constant_smi = false;
bool right_side_constant_null = false;
bool right_side_constant_1_char_string = false;
if (right_side.is_constant()) {
right_side_constant_smi = right_side.handle()->IsSmi();
right_side_constant_null = right_side.handle()->IsNull();
right_side_constant_1_char_string =
(right_side.handle()->IsString() &&
(String::cast(*right_side.handle())->length() == 1));
}
if (left_side_constant_smi || right_side_constant_smi) {
if (left_side_constant_smi && right_side_constant_smi) {
// Trivial case, comparing two constants.
int left_value = Smi::cast(*left_side.handle())->value();
int right_value = Smi::cast(*right_side.handle())->value();
switch (cc) {
case less:
dest->Goto(left_value < right_value);
break;
case equal:
dest->Goto(left_value == right_value);
break;
case greater_equal:
dest->Goto(left_value >= right_value);
break;
default:
UNREACHABLE();
}
} else {
// Only one side is a constant Smi.
// If left side is a constant Smi, reverse the operands.
// Since one side is a constant Smi, conversion order does not matter.
if (left_side_constant_smi) {
Result temp = left_side;
left_side = right_side;
right_side = temp;
cc = ReverseCondition(cc);
// This may reintroduce greater or less_equal as the value of cc.
// CompareStub and the inline code both support all values of cc.
}
// Implement comparison against a constant Smi, inlining the case
// where both sides are Smis.
left_side.ToRegister();
Register left_reg = left_side.reg();
Handle<Object> right_val = right_side.handle();
// Here we split control flow to the stub call and inlined cases
// before finally splitting it to the control destination. We use
// a jump target and branching to duplicate the virtual frame at
// the first split. We manually handle the off-frame references
// by reconstituting them on the non-fall-through path.
JumpTarget is_smi;
__ test(left_side.reg(), Immediate(kSmiTagMask));
is_smi.Branch(zero, taken);
bool is_for_loop_compare = (node->AsCompareOperation() != NULL)
&& node->AsCompareOperation()->is_for_loop_condition();
if (!is_for_loop_compare
&& CpuFeatures::IsSupported(SSE2)
&& right_val->IsSmi()) {
// Right side is a constant smi and left side has been checked
// not to be a smi.
CpuFeatures::Scope use_sse2(SSE2);
JumpTarget not_number;
__ cmp(FieldOperand(left_reg, HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
not_number.Branch(not_equal, &left_side);
__ movdbl(xmm1,
FieldOperand(left_reg, HeapNumber::kValueOffset));
int value = Smi::cast(*right_val)->value();
if (value == 0) {
__ xorpd(xmm0, xmm0);
} else {
Result temp = allocator()->Allocate();
__ mov(temp.reg(), Immediate(value));
__ cvtsi2sd(xmm0, Operand(temp.reg()));
temp.Unuse();
}
__ comisd(xmm1, xmm0);
// Jump to builtin for NaN.
not_number.Branch(parity_even, &left_side);
left_side.Unuse();
Condition double_cc = cc;
switch (cc) {
case less: double_cc = below; break;
case equal: double_cc = equal; break;
case less_equal: double_cc = below_equal; break;
case greater: double_cc = above; break;
case greater_equal: double_cc = above_equal; break;
default: UNREACHABLE();
}
dest->true_target()->Branch(double_cc);
dest->false_target()->Jump();
not_number.Bind(&left_side);
}
// Setup and call the compare stub.
CompareStub stub(cc, strict, kCantBothBeNaN);
Result result = frame_->CallStub(&stub, &left_side, &right_side);
result.ToRegister();
__ cmp(result.reg(), 0);
result.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
is_smi.Bind();
left_side = Result(left_reg);
right_side = Result(right_val);
// Test smi equality and comparison by signed int comparison.
if (IsUnsafeSmi(right_side.handle())) {
right_side.ToRegister();
__ cmp(left_side.reg(), Operand(right_side.reg()));
} else {
__ cmp(Operand(left_side.reg()), Immediate(right_side.handle()));
}
left_side.Unuse();
right_side.Unuse();
dest->Split(cc);
}
} else if (cc == equal &&
(left_side_constant_null || right_side_constant_null)) {
// To make null checks efficient, we check if either the left side or
// the right side is the constant 'null'.
// If so, we optimize the code by inlining a null check instead of
// calling the (very) general runtime routine for checking equality.
Result operand = left_side_constant_null ? right_side : left_side;
right_side.Unuse();
left_side.Unuse();
operand.ToRegister();
__ cmp(operand.reg(), Factory::null_value());
if (strict) {
operand.Unuse();
dest->Split(equal);
} else {
// The 'null' value is only equal to 'undefined' if using non-strict
// comparisons.
dest->true_target()->Branch(equal);
__ cmp(operand.reg(), Factory::undefined_value());
dest->true_target()->Branch(equal);
__ test(operand.reg(), Immediate(kSmiTagMask));
dest->false_target()->Branch(equal);
// It can be an undetectable object.
// Use a scratch register in preference to spilling operand.reg().
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(),
FieldOperand(operand.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(),
FieldOperand(temp.reg(), Map::kBitFieldOffset));
__ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
temp.Unuse();
operand.Unuse();
dest->Split(not_zero);
}
} else if (left_side_constant_1_char_string ||
right_side_constant_1_char_string) {
if (left_side_constant_1_char_string && right_side_constant_1_char_string) {
// Trivial case, comparing two constants.
int left_value = String::cast(*left_side.handle())->Get(0);
int right_value = String::cast(*right_side.handle())->Get(0);
switch (cc) {
case less:
dest->Goto(left_value < right_value);
break;
case equal:
dest->Goto(left_value == right_value);
break;
case greater_equal:
dest->Goto(left_value >= right_value);
break;
default:
UNREACHABLE();
}
} else {
// Only one side is a constant 1 character string.
// If left side is a constant 1-character string, reverse the operands.
// Since one side is a constant string, conversion order does not matter.
if (left_side_constant_1_char_string) {
Result temp = left_side;
left_side = right_side;
right_side = temp;
cc = ReverseCondition(cc);
// This may reintroduce greater or less_equal as the value of cc.
// CompareStub and the inline code both support all values of cc.
}
// Implement comparison against a constant string, inlining the case
// where both sides are strings.
left_side.ToRegister();
// Here we split control flow to the stub call and inlined cases
// before finally splitting it to the control destination. We use
// a jump target and branching to duplicate the virtual frame at
// the first split. We manually handle the off-frame references
// by reconstituting them on the non-fall-through path.
JumpTarget is_not_string, is_string;
Register left_reg = left_side.reg();
Handle<Object> right_val = right_side.handle();
__ test(left_side.reg(), Immediate(kSmiTagMask));
is_not_string.Branch(zero, &left_side);
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(),
FieldOperand(left_side.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(),
FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
// If we are testing for equality then make use of the symbol shortcut.
// Check if the right left hand side has the same type as the left hand
// side (which is always a symbol).
if (cc == equal) {
Label not_a_symbol;
ASSERT(kSymbolTag != 0);
// Ensure that no non-strings have the symbol bit set.
ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
__ test(temp.reg(), Immediate(kIsSymbolMask)); // Test the symbol bit.
__ j(zero, ¬_a_symbol);
// They are symbols, so do identity compare.
__ cmp(left_side.reg(), right_side.handle());
dest->true_target()->Branch(equal);
dest->false_target()->Branch(not_equal);
__ bind(¬_a_symbol);
}
// If the receiver is not a string of the type we handle call the stub.
__ and_(temp.reg(),
kIsNotStringMask | kStringRepresentationMask | kStringEncodingMask);
__ cmp(temp.reg(), kStringTag | kSeqStringTag | kAsciiStringTag);
temp.Unuse();
is_string.Branch(equal, &left_side);
// Setup and call the compare stub.
is_not_string.Bind(&left_side);
CompareStub stub(cc, strict, kCantBothBeNaN);
Result result = frame_->CallStub(&stub, &left_side, &right_side);
result.ToRegister();
__ cmp(result.reg(), 0);
result.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
is_string.Bind(&left_side);
// Here we know we have a sequential ASCII string.
left_side = Result(left_reg);
right_side = Result(right_val);
Result temp2 = allocator_->Allocate();
ASSERT(temp2.is_valid());
// Test string equality and comparison.
if (cc == equal) {
Label comparison_done;
__ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
Immediate(1));
__ j(not_equal, &comparison_done);
uint8_t char_value =
static_cast<uint8_t>(String::cast(*right_side.handle())->Get(0));
__ cmpb(FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize),
char_value);
__ bind(&comparison_done);
} else {
__ mov(temp2.reg(),
FieldOperand(left_side.reg(), String::kLengthOffset));
__ sub(Operand(temp2.reg()), Immediate(1));
Label comparison;
// If the length is 0 then our subtraction gave -1 which compares less
// than any character.
__ j(negative, &comparison);
// Otherwise load the first character.
__ movzx_b(temp2.reg(),
FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize));
__ bind(&comparison);
// Compare the first character of the string with out constant
// 1-character string.
uint8_t char_value =
static_cast<uint8_t>(String::cast(*right_side.handle())->Get(0));
__ cmp(Operand(temp2.reg()), Immediate(char_value));
Label characters_were_different;
__ j(not_equal, &characters_were_different);
// If the first character is the same then the long string sorts after
// the short one.
__ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
Immediate(1));
__ bind(&characters_were_different);
}
temp2.Unuse();
left_side.Unuse();
right_side.Unuse();
dest->Split(cc);
}
} else {
// Neither side is a constant Smi or null.
// If either side is a non-smi constant, skip the smi check.
bool known_non_smi =
(left_side.is_constant() && !left_side.handle()->IsSmi()) ||
(right_side.is_constant() && !right_side.handle()->IsSmi());
NaNInformation nan_info =
(CouldBeNaN(left_side) && CouldBeNaN(right_side)) ?
kBothCouldBeNaN :
kCantBothBeNaN;
left_side.ToRegister();
right_side.ToRegister();
if (known_non_smi) {
// When non-smi, call out to the compare stub.
CompareStub stub(cc, strict, nan_info);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
} else {
__ cmp(answer.reg(), 0);
}
answer.Unuse();
dest->Split(cc);
} else {
// Here we split control flow to the stub call and inlined cases
// before finally splitting it to the control destination. We use
// a jump target and branching to duplicate the virtual frame at
// the first split. We manually handle the off-frame references
// by reconstituting them on the non-fall-through path.
JumpTarget is_smi;
Register left_reg = left_side.reg();
Register right_reg = right_side.reg();
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), left_side.reg());
__ or_(temp.reg(), Operand(right_side.reg()));
__ test(temp.reg(), Immediate(kSmiTagMask));
temp.Unuse();
is_smi.Branch(zero, taken);
// When non-smi, call out to the compare stub.
CompareStub stub(cc, strict, nan_info);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
} else {
__ cmp(answer.reg(), 0);
}
answer.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
is_smi.Bind();
left_side = Result(left_reg);
right_side = Result(right_reg);
__ cmp(left_side.reg(), Operand(right_side.reg()));
right_side.Unuse();
left_side.Unuse();
dest->Split(cc);
}
}
}
// Call the function just below TOS on the stack with the given
// arguments. The receiver is the TOS.
void CodeGenerator::CallWithArguments(ZoneList<Expression*>* args,
CallFunctionFlags flags,
int position) {
// Push the arguments ("left-to-right") on the stack.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Record the position for debugging purposes.
CodeForSourcePosition(position);
// Use the shared code stub to call the function.
InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
CallFunctionStub call_function(arg_count, in_loop, flags);
Result answer = frame_->CallStub(&call_function, arg_count + 1);
// Restore context and replace function on the stack with the
// result of the stub invocation.
frame_->RestoreContextRegister();
frame_->SetElementAt(0, &answer);
}
void CodeGenerator::CallApplyLazy(Expression* applicand,
Expression* receiver,
VariableProxy* arguments,
int position) {
// An optimized implementation of expressions of the form
// x.apply(y, arguments).
// If the arguments object of the scope has not been allocated,
// and x.apply is Function.prototype.apply, this optimization
// just copies y and the arguments of the current function on the
// stack, as receiver and arguments, and calls x.
// In the implementation comments, we call x the applicand
// and y the receiver.
ASSERT(ArgumentsMode() == LAZY_ARGUMENTS_ALLOCATION);
ASSERT(arguments->IsArguments());
// Load applicand.apply onto the stack. This will usually
// give us a megamorphic load site. Not super, but it works.
Load(applicand);
frame()->Dup();
Handle<String> name = Factory::LookupAsciiSymbol("apply");
frame()->Push(name);
Result answer = frame()->CallLoadIC(RelocInfo::CODE_TARGET);
__ nop();
frame()->Push(&answer);
// Load the receiver and the existing arguments object onto the
// expression stack. Avoid allocating the arguments object here.
Load(receiver);
Result existing_args =
LoadFromSlot(scope()->arguments()->var()->slot(), NOT_INSIDE_TYPEOF);
frame()->Push(&existing_args);
// Emit the source position information after having loaded the
// receiver and the arguments.
CodeForSourcePosition(position);
// Contents of frame at this point:
// Frame[0]: arguments object of the current function or the hole.
// Frame[1]: receiver
// Frame[2]: applicand.apply
// Frame[3]: applicand.
// Check if the arguments object has been lazily allocated
// already. If so, just use that instead of copying the arguments
// from the stack. This also deals with cases where a local variable
// named 'arguments' has been introduced.
frame_->Dup();
Result probe = frame_->Pop();
{ VirtualFrame::SpilledScope spilled_scope;
Label slow, done;
bool try_lazy = true;
if (probe.is_constant()) {
try_lazy = probe.handle()->IsTheHole();
} else {
__ cmp(Operand(probe.reg()), Immediate(Factory::the_hole_value()));
probe.Unuse();
__ j(not_equal, &slow);
}
if (try_lazy) {
Label build_args;
// Get rid of the arguments object probe.
frame_->Drop(); // Can be called on a spilled frame.
// Stack now has 3 elements on it.
// Contents of stack at this point:
// esp[0]: receiver
// esp[1]: applicand.apply
// esp[2]: applicand.
// Check that the receiver really is a JavaScript object.
__ mov(eax, Operand(esp, 0));
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &build_args);
// We allow all JSObjects including JSFunctions. As long as
// JS_FUNCTION_TYPE is the last instance type and it is right
// after LAST_JS_OBJECT_TYPE, we do not have to check the upper
// bound.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
__ CmpObjectType(eax, FIRST_JS_OBJECT_TYPE, ecx);
__ j(below, &build_args);
// Check that applicand.apply is Function.prototype.apply.
__ mov(eax, Operand(esp, kPointerSize));
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &build_args);
__ CmpObjectType(eax, JS_FUNCTION_TYPE, ecx);
__ j(not_equal, &build_args);
__ mov(ecx, FieldOperand(eax, JSFunction::kSharedFunctionInfoOffset));
Handle<Code> apply_code(Builtins::builtin(Builtins::FunctionApply));
__ cmp(FieldOperand(ecx, SharedFunctionInfo::kCodeOffset),
Immediate(apply_code));
__ j(not_equal, &build_args);
// Check that applicand is a function.
__ mov(edi, Operand(esp, 2 * kPointerSize));
__ test(edi, Immediate(kSmiTagMask));
__ j(zero, &build_args);
__ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
__ j(not_equal, &build_args);
// Copy the arguments to this function possibly from the
// adaptor frame below it.
Label invoke, adapted;
__ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx),
Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(equal, &adapted);
// No arguments adaptor frame. Copy fixed number of arguments.
__ mov(eax, Immediate(scope()->num_parameters()));
for (int i = 0; i < scope()->num_parameters(); i++) {
__ push(frame_->ParameterAt(i));
}
__ jmp(&invoke);
// Arguments adaptor frame present. Copy arguments from there, but
// avoid copying too many arguments to avoid stack overflows.
__ bind(&adapted);
static const uint32_t kArgumentsLimit = 1 * KB;
__ mov(eax, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ SmiUntag(eax);
__ mov(ecx, Operand(eax));
__ cmp(eax, kArgumentsLimit);
__ j(above, &build_args);
// Loop through the arguments pushing them onto the execution
// stack. We don't inform the virtual frame of the push, so we don't
// have to worry about getting rid of the elements from the virtual
// frame.
Label loop;
// ecx is a small non-negative integer, due to the test above.
__ test(ecx, Operand(ecx));
__ j(zero, &invoke);
__ bind(&loop);
__ push(Operand(edx, ecx, times_pointer_size, 1 * kPointerSize));
__ dec(ecx);
__ j(not_zero, &loop);
// Invoke the function.
__ bind(&invoke);
ParameterCount actual(eax);
__ InvokeFunction(edi, actual, CALL_FUNCTION);
// Drop applicand.apply and applicand from the stack, and push
// the result of the function call, but leave the spilled frame
// unchanged, with 3 elements, so it is correct when we compile the
// slow-case code.
__ add(Operand(esp), Immediate(2 * kPointerSize));
__ push(eax);
// Stack now has 1 element:
// esp[0]: result
__ jmp(&done);
// Slow-case: Allocate the arguments object since we know it isn't
// there, and fall-through to the slow-case where we call
// applicand.apply.
__ bind(&build_args);
// Stack now has 3 elements, because we have jumped from where:
// esp[0]: receiver
// esp[1]: applicand.apply
// esp[2]: applicand.
// StoreArgumentsObject requires a correct frame, and may modify it.
Result arguments_object = StoreArgumentsObject(false);
frame_->SpillAll();
arguments_object.ToRegister();
frame_->EmitPush(arguments_object.reg());
arguments_object.Unuse();
// Stack and frame now have 4 elements.
__ bind(&slow);
}
// Generic computation of x.apply(y, args) with no special optimization.
// Flip applicand.apply and applicand on the stack, so
// applicand looks like the receiver of the applicand.apply call.
// Then process it as a normal function call.
__ mov(eax, Operand(esp, 3 * kPointerSize));
__ mov(ebx, Operand(esp, 2 * kPointerSize));
__ mov(Operand(esp, 2 * kPointerSize), eax);
__ mov(Operand(esp, 3 * kPointerSize), ebx);
CallFunctionStub call_function(2, NOT_IN_LOOP, NO_CALL_FUNCTION_FLAGS);
Result res = frame_->CallStub(&call_function, 3);
// The function and its two arguments have been dropped.
frame_->Drop(1); // Drop the receiver as well.
res.ToRegister();
frame_->EmitPush(res.reg());
// Stack now has 1 element:
// esp[0]: result
if (try_lazy) __ bind(&done);
} // End of spilled scope.
// Restore the context register after a call.
frame_->RestoreContextRegister();
}
class DeferredStackCheck: public DeferredCode {
public:
DeferredStackCheck() {
set_comment("[ DeferredStackCheck");
}
virtual void Generate();
};
void DeferredStackCheck::Generate() {
StackCheckStub stub;
__ CallStub(&stub);
}
void CodeGenerator::CheckStack() {
DeferredStackCheck* deferred = new DeferredStackCheck;
ExternalReference stack_limit =
ExternalReference::address_of_stack_limit();
__ cmp(esp, Operand::StaticVariable(stack_limit));
deferred->Branch(below);
deferred->BindExit();
}
void CodeGenerator::VisitAndSpill(Statement* statement) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
Visit(statement);
if (frame_ != NULL) {
frame_->SpillAll();
}
set_in_spilled_code(true);
}
void CodeGenerator::VisitStatementsAndSpill(ZoneList<Statement*>* statements) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
VisitStatements(statements);
if (frame_ != NULL) {
frame_->SpillAll();
}
set_in_spilled_code(true);
}
void CodeGenerator::VisitStatements(ZoneList<Statement*>* statements) {
ASSERT(!in_spilled_code());
for (int i = 0; has_valid_frame() && i < statements->length(); i++) {
Visit(statements->at(i));
}
}
void CodeGenerator::VisitBlock(Block* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ Block");
CodeForStatementPosition(node);
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
VisitStatements(node->statements());
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
node->break_target()->Unuse();
}
void CodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
// Call the runtime to declare the globals. The inevitable call
// will sync frame elements to memory anyway, so we do it eagerly to
// allow us to push the arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi); // The context is the first argument.
frame_->EmitPush(Immediate(pairs));
frame_->EmitPush(Immediate(Smi::FromInt(is_eval() ? 1 : 0)));
Result ignored = frame_->CallRuntime(Runtime::kDeclareGlobals, 3);
// Return value is ignored.
}
void CodeGenerator::VisitDeclaration(Declaration* node) {
Comment cmnt(masm_, "[ Declaration");
Variable* var = node->proxy()->var();
ASSERT(var != NULL); // must have been resolved
Slot* slot = var->slot();
// If it was not possible to allocate the variable at compile time,
// we need to "declare" it at runtime to make sure it actually
// exists in the local context.
if (slot != NULL && slot->type() == Slot::LOOKUP) {
// Variables with a "LOOKUP" slot were introduced as non-locals
// during variable resolution and must have mode DYNAMIC.
ASSERT(var->is_dynamic());
// For now, just do a runtime call. Sync the virtual frame eagerly
// so we can simply push the arguments into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(var->name()));
// Declaration nodes are always introduced in one of two modes.
ASSERT(node->mode() == Variable::VAR || node->mode() == Variable::CONST);
PropertyAttributes attr = node->mode() == Variable::VAR ? NONE : READ_ONLY;
frame_->EmitPush(Immediate(Smi::FromInt(attr)));
// Push initial value, if any.
// Note: For variables we must not push an initial value (such as
// 'undefined') because we may have a (legal) redeclaration and we
// must not destroy the current value.
if (node->mode() == Variable::CONST) {
frame_->EmitPush(Immediate(Factory::the_hole_value()));
} else if (node->fun() != NULL) {
Load(node->fun());
} else {
frame_->EmitPush(Immediate(Smi::FromInt(0))); // no initial value!
}
Result ignored = frame_->CallRuntime(Runtime::kDeclareContextSlot, 4);
// Ignore the return value (declarations are statements).
return;
}
ASSERT(!var->is_global());
// If we have a function or a constant, we need to initialize the variable.
Expression* val = NULL;
if (node->mode() == Variable::CONST) {
val = new Literal(Factory::the_hole_value());
} else {
val = node->fun(); // NULL if we don't have a function
}
if (val != NULL) {
{
// Set the initial value.
Reference target(this, node->proxy());
Load(val);
target.SetValue(NOT_CONST_INIT);
// The reference is removed from the stack (preserving TOS) when
// it goes out of scope.
}
// Get rid of the assigned value (declarations are statements).
frame_->Drop();
}
}
void CodeGenerator::VisitExpressionStatement(ExpressionStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ExpressionStatement");
CodeForStatementPosition(node);
Expression* expression = node->expression();
expression->MarkAsStatement();
Load(expression);
// Remove the lingering expression result from the top of stack.
frame_->Drop();
}
void CodeGenerator::VisitEmptyStatement(EmptyStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "// EmptyStatement");
CodeForStatementPosition(node);
// nothing to do
}
void CodeGenerator::VisitIfStatement(IfStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ IfStatement");
// Generate different code depending on which parts of the if statement
// are present or not.
bool has_then_stm = node->HasThenStatement();
bool has_else_stm = node->HasElseStatement();
CodeForStatementPosition(node);
JumpTarget exit;
if (has_then_stm && has_else_stm) {
JumpTarget then;
JumpTarget else_;
ControlDestination dest(&then, &else_, true);
LoadCondition(node->condition(), &dest, true);
if (dest.false_was_fall_through()) {
// The else target was bound, so we compile the else part first.
Visit(node->else_statement());
// We may have dangling jumps to the then part.
if (then.is_linked()) {
if (has_valid_frame()) exit.Jump();
then.Bind();
Visit(node->then_statement());
}
} else {
// The then target was bound, so we compile the then part first.
Visit(node->then_statement());
if (else_.is_linked()) {
if (has_valid_frame()) exit.Jump();
else_.Bind();
Visit(node->else_statement());
}
}
} else if (has_then_stm) {
ASSERT(!has_else_stm);
JumpTarget then;
ControlDestination dest(&then, &exit, true);
LoadCondition(node->condition(), &dest, true);
if (dest.false_was_fall_through()) {
// The exit label was bound. We may have dangling jumps to the
// then part.
if (then.is_linked()) {
exit.Unuse();
exit.Jump();
then.Bind();
Visit(node->then_statement());
}
} else {
// The then label was bound.
Visit(node->then_statement());
}
} else if (has_else_stm) {
ASSERT(!has_then_stm);
JumpTarget else_;
ControlDestination dest(&exit, &else_, false);
LoadCondition(node->condition(), &dest, true);
if (dest.true_was_fall_through()) {
// The exit label was bound. We may have dangling jumps to the
// else part.
if (else_.is_linked()) {
exit.Unuse();
exit.Jump();
else_.Bind();
Visit(node->else_statement());
}
} else {
// The else label was bound.
Visit(node->else_statement());
}
} else {
ASSERT(!has_then_stm && !has_else_stm);
// We only care about the condition's side effects (not its value
// or control flow effect). LoadCondition is called without
// forcing control flow.
ControlDestination dest(&exit, &exit, true);
LoadCondition(node->condition(), &dest, false);
if (!dest.is_used()) {
// We got a value on the frame rather than (or in addition to)
// control flow.
frame_->Drop();
}
}
if (exit.is_linked()) {
exit.Bind();
}
}
void CodeGenerator::VisitContinueStatement(ContinueStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ContinueStatement");
CodeForStatementPosition(node);
node->target()->continue_target()->Jump();
}
void CodeGenerator::VisitBreakStatement(BreakStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ BreakStatement");
CodeForStatementPosition(node);
node->target()->break_target()->Jump();
}
void CodeGenerator::VisitReturnStatement(ReturnStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ReturnStatement");
CodeForStatementPosition(node);
Load(node->expression());
Result return_value = frame_->Pop();
masm()->WriteRecordedPositions();
if (function_return_is_shadowed_) {
function_return_.Jump(&return_value);
} else {
frame_->PrepareForReturn();
if (function_return_.is_bound()) {
// If the function return label is already bound we reuse the
// code by jumping to the return site.
function_return_.Jump(&return_value);
} else {
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}
}
void CodeGenerator::GenerateReturnSequence(Result* return_value) {
// The return value is a live (but not currently reference counted)
// reference to eax. This is safe because the current frame does not
// contain a reference to eax (it is prepared for the return by spilling
// all registers).
if (FLAG_trace) {
frame_->Push(return_value);
*return_value = frame_->CallRuntime(Runtime::kTraceExit, 1);
}
return_value->ToRegister(eax);
// Add a label for checking the size of the code used for returning.
Label check_exit_codesize;
masm_->bind(&check_exit_codesize);
// Leave the frame and return popping the arguments and the
// receiver.
frame_->Exit();
masm_->ret((scope()->num_parameters() + 1) * kPointerSize);
DeleteFrame();
#ifdef ENABLE_DEBUGGER_SUPPORT
// Check that the size of the code used for returning matches what is
// expected by the debugger.
ASSERT_EQ(Assembler::kJSReturnSequenceLength,
masm_->SizeOfCodeGeneratedSince(&check_exit_codesize));
#endif
}
void CodeGenerator::VisitWithEnterStatement(WithEnterStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ WithEnterStatement");
CodeForStatementPosition(node);
Load(node->expression());
Result context;
if (node->is_catch_block()) {
context = frame_->CallRuntime(Runtime::kPushCatchContext, 1);
} else {
context = frame_->CallRuntime(Runtime::kPushContext, 1);
}
// Update context local.
frame_->SaveContextRegister();
// Verify that the runtime call result and esi agree.
if (FLAG_debug_code) {
__ cmp(context.reg(), Operand(esi));
__ Assert(equal, "Runtime::NewContext should end up in esi");
}
}
void CodeGenerator::VisitWithExitStatement(WithExitStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ WithExitStatement");
CodeForStatementPosition(node);
// Pop context.
__ mov(esi, ContextOperand(esi, Context::PREVIOUS_INDEX));
// Update context local.
frame_->SaveContextRegister();
}
void CodeGenerator::VisitSwitchStatement(SwitchStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ SwitchStatement");
CodeForStatementPosition(node);
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
// Compile the switch value.
Load(node->tag());
ZoneList<CaseClause*>* cases = node->cases();
int length = cases->length();
CaseClause* default_clause = NULL;
JumpTarget next_test;
// Compile the case label expressions and comparisons. Exit early
// if a comparison is unconditionally true. The target next_test is
// bound before the loop in order to indicate control flow to the
// first comparison.
next_test.Bind();
for (int i = 0; i < length && !next_test.is_unused(); i++) {
CaseClause* clause = cases->at(i);
// The default is not a test, but remember it for later.
if (clause->is_default()) {
default_clause = clause;
continue;
}
Comment cmnt(masm_, "[ Case comparison");
// We recycle the same target next_test for each test. Bind it if
// the previous test has not done so and then unuse it for the
// loop.
if (next_test.is_linked()) {
next_test.Bind();
}
next_test.Unuse();
// Duplicate the switch value.
frame_->Dup();
// Compile the label expression.
Load(clause->label());
// Compare and branch to the body if true or the next test if
// false. Prefer the next test as a fall through.
ControlDestination dest(clause->body_target(), &next_test, false);
Comparison(node, equal, true, &dest);
// If the comparison fell through to the true target, jump to the
// actual body.
if (dest.true_was_fall_through()) {
clause->body_target()->Unuse();
clause->body_target()->Jump();
}
}
// If there was control flow to a next test from the last one
// compiled, compile a jump to the default or break target.
if (!next_test.is_unused()) {
if (next_test.is_linked()) {
next_test.Bind();
}
// Drop the switch value.
frame_->Drop();
if (default_clause != NULL) {
default_clause->body_target()->Jump();
} else {
node->break_target()->Jump();
}
}
// The last instruction emitted was a jump, either to the default
// clause or the break target, or else to a case body from the loop
// that compiles the tests.
ASSERT(!has_valid_frame());
// Compile case bodies as needed.
for (int i = 0; i < length; i++) {
CaseClause* clause = cases->at(i);
// There are two ways to reach the body: from the corresponding
// test or as the fall through of the previous body.
if (clause->body_target()->is_linked() || has_valid_frame()) {
if (clause->body_target()->is_linked()) {
if (has_valid_frame()) {
// If we have both a jump to the test and a fall through, put
// a jump on the fall through path to avoid the dropping of
// the switch value on the test path. The exception is the
// default which has already had the switch value dropped.
if (clause->is_default()) {
clause->body_target()->Bind();
} else {
JumpTarget body;
body.Jump();
clause->body_target()->Bind();
frame_->Drop();
body.Bind();
}
} else {
// No fall through to worry about.
clause->body_target()->Bind();
if (!clause->is_default()) {
frame_->Drop();
}
}
} else {
// Otherwise, we have only fall through.
ASSERT(has_valid_frame());
}
// We are now prepared to compile the body.
Comment cmnt(masm_, "[ Case body");
VisitStatements(clause->statements());
}
clause->body_target()->Unuse();
}
// We may not have a valid frame here so bind the break target only
// if needed.
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
node->break_target()->Unuse();
}
void CodeGenerator::VisitDoWhileStatement(DoWhileStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ DoWhileStatement");
CodeForStatementPosition(node);
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
JumpTarget body(JumpTarget::BIDIRECTIONAL);
IncrementLoopNesting();
ConditionAnalysis info = AnalyzeCondition(node->cond());
// Label the top of the loop for the backward jump if necessary.
switch (info) {
case ALWAYS_TRUE:
// Use the continue target.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
break;
case ALWAYS_FALSE:
// No need to label it.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
break;
case DONT_KNOW:
// Continue is the test, so use the backward body target.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
body.Bind();
break;
}
CheckStack(); // TODO(1222600): ignore if body contains calls.
Visit(node->body());
// Compile the test.
switch (info) {
case ALWAYS_TRUE:
// If control flow can fall off the end of the body, jump back to
// the top and bind the break target at the exit.
if (has_valid_frame()) {
node->continue_target()->Jump();
}
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
break;
case ALWAYS_FALSE:
// We may have had continues or breaks in the body.
if (node->continue_target()->is_linked()) {
node->continue_target()->Bind();
}
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
break;
case DONT_KNOW:
// We have to compile the test expression if it can be reached by
// control flow falling out of the body or via continue.
if (node->continue_target()->is_linked()) {
node->continue_target()->Bind();
}
if (has_valid_frame()) {
Comment cmnt(masm_, "[ DoWhileCondition");
CodeForDoWhileConditionPosition(node);
ControlDestination dest(&body, node->break_target(), false);
LoadCondition(node->cond(), &dest, true);
}
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
break;
}
DecrementLoopNesting();
}
void CodeGenerator::VisitWhileStatement(WhileStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ WhileStatement");
CodeForStatementPosition(node);
// If the condition is always false and has no side effects, we do not
// need to compile anything.
ConditionAnalysis info = AnalyzeCondition(node->cond());
if (info == ALWAYS_FALSE) return;
// Do not duplicate conditions that may have function literal
// subexpressions. This can cause us to compile the function literal
// twice.
bool test_at_bottom = !node->may_have_function_literal();
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
IncrementLoopNesting();
JumpTarget body;
if (test_at_bottom) {
body.set_direction(JumpTarget::BIDIRECTIONAL);
}
// Based on the condition analysis, compile the test as necessary.
switch (info) {
case ALWAYS_TRUE:
// We will not compile the test expression. Label the top of the
// loop with the continue target.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
break;
case DONT_KNOW: {
if (test_at_bottom) {
// Continue is the test at the bottom, no need to label the test
// at the top. The body is a backward target.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
} else {
// Label the test at the top as the continue target. The body
// is a forward-only target.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
}
// Compile the test with the body as the true target and preferred
// fall-through and with the break target as the false target.
ControlDestination dest(&body, node->break_target(), true);
LoadCondition(node->cond(), &dest, true);
if (dest.false_was_fall_through()) {
// If we got the break target as fall-through, the test may have
// been unconditionally false (if there are no jumps to the
// body).
if (!body.is_linked()) {
DecrementLoopNesting();
return;
}
// Otherwise, jump around the body on the fall through and then
// bind the body target.
node->break_target()->Unuse();
node->break_target()->Jump();
body.Bind();
}
break;
}
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
CheckStack(); // TODO(1222600): ignore if body contains calls.
Visit(node->body());
// Based on the condition analysis, compile the backward jump as
// necessary.
switch (info) {
case ALWAYS_TRUE:
// The loop body has been labeled with the continue target.
if (has_valid_frame()) {
node->continue_target()->Jump();
}
break;
case DONT_KNOW:
if (test_at_bottom) {
// If we have chosen to recompile the test at the bottom, then
// it is the continue target.
if (node->continue_target()->is_linked()) {
node->continue_target()->Bind();
}
if (has_valid_frame()) {
// The break target is the fall-through (body is a backward
// jump from here and thus an invalid fall-through).
ControlDestination dest(&body, node->break_target(), false);
LoadCondition(node->cond(), &dest, true);
}
} else {
// If we have chosen not to recompile the test at the bottom,
// jump back to the one at the top.
if (has_valid_frame()) {
node->continue_target()->Jump();
}
}
break;
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
// The break target may be already bound (by the condition), or there
// may not be a valid frame. Bind it only if needed.
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
DecrementLoopNesting();
}
void CodeGenerator::VisitForStatement(ForStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ForStatement");
CodeForStatementPosition(node);
// Compile the init expression if present.
if (node->init() != NULL) {
Visit(node->init());
}
// If the condition is always false and has no side effects, we do not
// need to compile anything else.
ConditionAnalysis info = AnalyzeCondition(node->cond());
if (info == ALWAYS_FALSE) return;
// Do not duplicate conditions that may have function literal
// subexpressions. This can cause us to compile the function literal
// twice.
bool test_at_bottom = !node->may_have_function_literal();
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
IncrementLoopNesting();
// Target for backward edge if no test at the bottom, otherwise
// unused.
JumpTarget loop(JumpTarget::BIDIRECTIONAL);
// Target for backward edge if there is a test at the bottom,
// otherwise used as target for test at the top.
JumpTarget body;
if (test_at_bottom) {
body.set_direction(JumpTarget::BIDIRECTIONAL);
}
// Based on the condition analysis, compile the test as necessary.
switch (info) {
case ALWAYS_TRUE:
// We will not compile the test expression. Label the top of the
// loop.
if (node->next() == NULL) {
// Use the continue target if there is no update expression.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
} else {
// Otherwise use the backward loop target.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
loop.Bind();
}
break;
case DONT_KNOW: {
if (test_at_bottom) {
// Continue is either the update expression or the test at the
// bottom, no need to label the test at the top.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
} else if (node->next() == NULL) {
// We are not recompiling the test at the bottom and there is no
// update expression.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
} else {
// We are not recompiling the test at the bottom and there is an
// update expression.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
loop.Bind();
}
// Compile the test with the body as the true target and preferred
// fall-through and with the break target as the false target.
ControlDestination dest(&body, node->break_target(), true);
LoadCondition(node->cond(), &dest, true);
if (dest.false_was_fall_through()) {
// If we got the break target as fall-through, the test may have
// been unconditionally false (if there are no jumps to the
// body).
if (!body.is_linked()) {
DecrementLoopNesting();
return;
}
// Otherwise, jump around the body on the fall through and then
// bind the body target.
node->break_target()->Unuse();
node->break_target()->Jump();
body.Bind();
}
break;
}
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
CheckStack(); // TODO(1222600): ignore if body contains calls.
Visit(node->body());
// If there is an update expression, compile it if necessary.
if (node->next() != NULL) {
if (node->continue_target()->is_linked()) {
node->continue_target()->Bind();
}
// Control can reach the update by falling out of the body or by a
// continue.
if (has_valid_frame()) {
// Record the source position of the statement as this code which
// is after the code for the body actually belongs to the loop
// statement and not the body.
CodeForStatementPosition(node);
Visit(node->next());
}
}
// Based on the condition analysis, compile the backward jump as
// necessary.
switch (info) {
case ALWAYS_TRUE:
if (has_valid_frame()) {
if (node->next() == NULL) {
node->continue_target()->Jump();
} else {
loop.Jump();
}
}
break;
case DONT_KNOW:
if (test_at_bottom) {
if (node->continue_target()->is_linked()) {
// We can have dangling jumps to the continue target if there
// was no update expression.
node->continue_target()->Bind();
}
// Control can reach the test at the bottom by falling out of
// the body, by a continue in the body, or from the update
// expression.
if (has_valid_frame()) {
// The break target is the fall-through (body is a backward
// jump from here).
ControlDestination dest(&body, node->break_target(), false);
LoadCondition(node->cond(), &dest, true);
}
} else {
// Otherwise, jump back to the test at the top.
if (has_valid_frame()) {
if (node->next() == NULL) {
node->continue_target()->Jump();
} else {
loop.Jump();
}
}
}
break;
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
// The break target may be already bound (by the condition), or
// there may not be a valid frame. Bind it only if needed.
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
DecrementLoopNesting();
}
void CodeGenerator::VisitForInStatement(ForInStatement* node) {
ASSERT(!in_spilled_code());
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ ForInStatement");
CodeForStatementPosition(node);
JumpTarget primitive;
JumpTarget jsobject;
JumpTarget fixed_array;
JumpTarget entry(JumpTarget::BIDIRECTIONAL);
JumpTarget end_del_check;
JumpTarget exit;
// Get the object to enumerate over (converted to JSObject).
LoadAndSpill(node->enumerable());
// Both SpiderMonkey and kjs ignore null and undefined in contrast
// to the specification. 12.6.4 mandates a call to ToObject.
frame_->EmitPop(eax);
// eax: value to be iterated over
__ cmp(eax, Factory::undefined_value());
exit.Branch(equal);
__ cmp(eax, Factory::null_value());
exit.Branch(equal);
// Stack layout in body:
// [iteration counter (smi)] <- slot 0
// [length of array] <- slot 1
// [FixedArray] <- slot 2
// [Map or 0] <- slot 3
// [Object] <- slot 4
// Check if enumerable is already a JSObject
// eax: value to be iterated over
__ test(eax, Immediate(kSmiTagMask));
primitive.Branch(zero);
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
jsobject.Branch(above_equal);
primitive.Bind();
frame_->EmitPush(eax);
frame_->InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION, 1);
// function call returns the value in eax, which is where we want it below
jsobject.Bind();
// Get the set of properties (as a FixedArray or Map).
// eax: value to be iterated over
frame_->EmitPush(eax); // Push the object being iterated over.
// Check cache validity in generated code. This is a fast case for
// the JSObject::IsSimpleEnum cache validity checks. If we cannot
// guarantee cache validity, call the runtime system to check cache
// validity or get the property names in a fixed array.
JumpTarget call_runtime;
JumpTarget loop(JumpTarget::BIDIRECTIONAL);
JumpTarget check_prototype;
JumpTarget use_cache;
__ mov(ecx, eax);
loop.Bind();
// Check that there are no elements.
__ mov(edx, FieldOperand(ecx, JSObject::kElementsOffset));
__ cmp(Operand(edx), Immediate(Factory::empty_fixed_array()));
call_runtime.Branch(not_equal);
// Check that instance descriptors are not empty so that we can
// check for an enum cache. Leave the map in ebx for the subsequent
// prototype load.
__ mov(ebx, FieldOperand(ecx, HeapObject::kMapOffset));
__ mov(edx, FieldOperand(ebx, Map::kInstanceDescriptorsOffset));
__ cmp(Operand(edx), Immediate(Factory::empty_descriptor_array()));
call_runtime.Branch(equal);
// Check that there in an enum cache in the non-empty instance
// descriptors. This is the case if the next enumeration index
// field does not contain a smi.
__ mov(edx, FieldOperand(edx, DescriptorArray::kEnumerationIndexOffset));
__ test(edx, Immediate(kSmiTagMask));
call_runtime.Branch(zero);
// For all objects but the receiver, check that the cache is empty.
__ cmp(ecx, Operand(eax));
check_prototype.Branch(equal);
__ mov(edx, FieldOperand(edx, DescriptorArray::kEnumCacheBridgeCacheOffset));
__ cmp(Operand(edx), Immediate(Factory::empty_fixed_array()));
call_runtime.Branch(not_equal);
check_prototype.Bind();
// Load the prototype from the map and loop if non-null.
__ mov(ecx, FieldOperand(ebx, Map::kPrototypeOffset));
__ cmp(Operand(ecx), Immediate(Factory::null_value()));
loop.Branch(not_equal);
// The enum cache is valid. Load the map of the object being
// iterated over and use the cache for the iteration.
__ mov(eax, FieldOperand(eax, HeapObject::kMapOffset));
use_cache.Jump();
call_runtime.Bind();
// Call the runtime to get the property names for the object.
frame_->EmitPush(eax); // push the Object (slot 4) for the runtime call
frame_->CallRuntime(Runtime::kGetPropertyNamesFast, 1);
// If we got a map from the runtime call, we can do a fast
// modification check. Otherwise, we got a fixed array, and we have
// to do a slow check.
// eax: map or fixed array (result from call to
// Runtime::kGetPropertyNamesFast)
__ mov(edx, Operand(eax));
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ cmp(ecx, Factory::meta_map());
fixed_array.Branch(not_equal);
use_cache.Bind();
// Get enum cache
// eax: map (either the result from a call to
// Runtime::kGetPropertyNamesFast or has been fetched directly from
// the object)
__ mov(ecx, Operand(eax));
__ mov(ecx, FieldOperand(ecx, Map::kInstanceDescriptorsOffset));
// Get the bridge array held in the enumeration index field.
__ mov(ecx, FieldOperand(ecx, DescriptorArray::kEnumerationIndexOffset));
// Get the cache from the bridge array.
__ mov(edx, FieldOperand(ecx, DescriptorArray::kEnumCacheBridgeCacheOffset));
frame_->EmitPush(eax); // <- slot 3
frame_->EmitPush(edx); // <- slot 2
__ mov(eax, FieldOperand(edx, FixedArray::kLengthOffset));
__ SmiTag(eax);
frame_->EmitPush(eax); // <- slot 1
frame_->EmitPush(Immediate(Smi::FromInt(0))); // <- slot 0
entry.Jump();
fixed_array.Bind();
// eax: fixed array (result from call to Runtime::kGetPropertyNamesFast)
frame_->EmitPush(Immediate(Smi::FromInt(0))); // <- slot 3
frame_->EmitPush(eax); // <- slot 2
// Push the length of the array and the initial index onto the stack.
__ mov(eax, FieldOperand(eax, FixedArray::kLengthOffset));
__ SmiTag(eax);
frame_->EmitPush(eax); // <- slot 1
frame_->EmitPush(Immediate(Smi::FromInt(0))); // <- slot 0
// Condition.
entry.Bind();
// Grab the current frame's height for the break and continue
// targets only after all the state is pushed on the frame.
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
__ mov(eax, frame_->ElementAt(0)); // load the current count
__ cmp(eax, frame_->ElementAt(1)); // compare to the array length
node->break_target()->Branch(above_equal);
// Get the i'th entry of the array.
__ mov(edx, frame_->ElementAt(2));
__ mov(ebx, Operand(edx, eax, times_2,
FixedArray::kHeaderSize - kHeapObjectTag));
// Get the expected map from the stack or a zero map in the
// permanent slow case eax: current iteration count ebx: i'th entry
// of the enum cache
__ mov(edx, frame_->ElementAt(3));
// Check if the expected map still matches that of the enumerable.
// If not, we have to filter the key.
// eax: current iteration count
// ebx: i'th entry of the enum cache
// edx: expected map value
__ mov(ecx, frame_->ElementAt(4));
__ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
__ cmp(ecx, Operand(edx));
end_del_check.Branch(equal);
// Convert the entry to a string (or null if it isn't a property anymore).
frame_->EmitPush(frame_->ElementAt(4)); // push enumerable
frame_->EmitPush(ebx); // push entry
frame_->InvokeBuiltin(Builtins::FILTER_KEY, CALL_FUNCTION, 2);
__ mov(ebx, Operand(eax));
// If the property has been removed while iterating, we just skip it.
__ cmp(ebx, Factory::null_value());
node->continue_target()->Branch(equal);
end_del_check.Bind();
// Store the entry in the 'each' expression and take another spin in the
// loop. edx: i'th entry of the enum cache (or string there of)
frame_->EmitPush(ebx);
{ Reference each(this, node->each());
// Loading a reference may leave the frame in an unspilled state.
frame_->SpillAll();
if (!each.is_illegal()) {
if (each.size() > 0) {
frame_->EmitPush(frame_->ElementAt(each.size()));
each.SetValue(NOT_CONST_INIT);
frame_->Drop(2);
} else {
// If the reference was to a slot we rely on the convenient property
// that it doesn't matter whether a value (eg, ebx pushed above) is
// right on top of or right underneath a zero-sized reference.
each.SetValue(NOT_CONST_INIT);
frame_->Drop();
}
}
}
// Unloading a reference may leave the frame in an unspilled state.
frame_->SpillAll();
// Body.
CheckStack(); // TODO(1222600): ignore if body contains calls.
VisitAndSpill(node->body());
// Next. Reestablish a spilled frame in case we are coming here via
// a continue in the body.
node->continue_target()->Bind();
frame_->SpillAll();
frame_->EmitPop(eax);
__ add(Operand(eax), Immediate(Smi::FromInt(1)));
frame_->EmitPush(eax);
entry.Jump();
// Cleanup. No need to spill because VirtualFrame::Drop is safe for
// any frame.
node->break_target()->Bind();
frame_->Drop(5);
// Exit.
exit.Bind();
node->continue_target()->Unuse();
node->break_target()->Unuse();
}
void CodeGenerator::VisitTryCatchStatement(TryCatchStatement* node) {
ASSERT(!in_spilled_code());
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ TryCatchStatement");
CodeForStatementPosition(node);
JumpTarget try_block;
JumpTarget exit;
try_block.Call();
// --- Catch block ---
frame_->EmitPush(eax);
// Store the caught exception in the catch variable.
Variable* catch_var = node->catch_var()->var();
ASSERT(catch_var != NULL && catch_var->slot() != NULL);
StoreToSlot(catch_var->slot(), NOT_CONST_INIT);
// Remove the exception from the stack.
frame_->Drop();
VisitStatementsAndSpill(node->catch_block()->statements());
if (has_valid_frame()) {
exit.Jump();
}
// --- Try block ---
try_block.Bind();
frame_->PushTryHandler(TRY_CATCH_HANDLER);
int handler_height = frame_->height();
// Shadow the jump targets for all escapes from the try block, including
// returns. During shadowing, the original target is hidden as the
// ShadowTarget and operations on the original actually affect the
// shadowing target.
//
// We should probably try to unify the escaping targets and the return
// target.
int nof_escapes = node->escaping_targets()->length();
List<ShadowTarget*> shadows(1 + nof_escapes);
// Add the shadow target for the function return.
static const int kReturnShadowIndex = 0;
shadows.Add(new ShadowTarget(&function_return_));
bool function_return_was_shadowed = function_return_is_shadowed_;
function_return_is_shadowed_ = true;
ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
// Add the remaining shadow targets.
for (int i = 0; i < nof_escapes; i++) {
shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
}
// Generate code for the statements in the try block.
VisitStatementsAndSpill(node->try_block()->statements());
// Stop the introduced shadowing and count the number of required unlinks.
// After shadowing stops, the original targets are unshadowed and the
// ShadowTargets represent the formerly shadowing targets.
bool has_unlinks = false;
for (int i = 0; i < shadows.length(); i++) {
shadows[i]->StopShadowing();
has_unlinks = has_unlinks || shadows[i]->is_linked();
}
function_return_is_shadowed_ = function_return_was_shadowed;
// Get an external reference to the handler address.
ExternalReference handler_address(Top::k_handler_address);
// Make sure that there's nothing left on the stack above the
// handler structure.
if (FLAG_debug_code) {
__ mov(eax, Operand::StaticVariable(handler_address));
__ cmp(esp, Operand(eax));
__ Assert(equal, "stack pointer should point to top handler");
}
// If we can fall off the end of the try block, unlink from try chain.
if (has_valid_frame()) {
// The next handler address is on top of the frame. Unlink from
// the handler list and drop the rest of this handler from the
// frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (has_unlinks) {
exit.Jump();
}
}
// Generate unlink code for the (formerly) shadowing targets that
// have been jumped to. Deallocate each shadow target.
Result return_value;
for (int i = 0; i < shadows.length(); i++) {
if (shadows[i]->is_linked()) {
// Unlink from try chain; be careful not to destroy the TOS if
// there is one.
if (i == kReturnShadowIndex) {
shadows[i]->Bind(&return_value);
return_value.ToRegister(eax);
} else {
shadows[i]->Bind();
}
// Because we can be jumping here (to spilled code) from
// unspilled code, we need to reestablish a spilled frame at
// this block.
frame_->SpillAll();
// Reload sp from the top handler, because some statements that we
// break from (eg, for...in) may have left stuff on the stack.
__ mov(esp, Operand::StaticVariable(handler_address));
frame_->Forget(frame_->height() - handler_height);
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (i == kReturnShadowIndex) {
if (!function_return_is_shadowed_) frame_->PrepareForReturn();
shadows[i]->other_target()->Jump(&return_value);
} else {
shadows[i]->other_target()->Jump();
}
}
}
exit.Bind();
}
void CodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* node) {
ASSERT(!in_spilled_code());
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ TryFinallyStatement");
CodeForStatementPosition(node);
// State: Used to keep track of reason for entering the finally
// block. Should probably be extended to hold information for
// break/continue from within the try block.
enum { FALLING, THROWING, JUMPING };
JumpTarget try_block;
JumpTarget finally_block;
try_block.Call();
frame_->EmitPush(eax);
// In case of thrown exceptions, this is where we continue.
__ Set(ecx, Immediate(Smi::FromInt(THROWING)));
finally_block.Jump();
// --- Try block ---
try_block.Bind();
frame_->PushTryHandler(TRY_FINALLY_HANDLER);
int handler_height = frame_->height();
// Shadow the jump targets for all escapes from the try block, including
// returns. During shadowing, the original target is hidden as the
// ShadowTarget and operations on the original actually affect the
// shadowing target.
//
// We should probably try to unify the escaping targets and the return
// target.
int nof_escapes = node->escaping_targets()->length();
List<ShadowTarget*> shadows(1 + nof_escapes);
// Add the shadow target for the function return.
static const int kReturnShadowIndex = 0;
shadows.Add(new ShadowTarget(&function_return_));
bool function_return_was_shadowed = function_return_is_shadowed_;
function_return_is_shadowed_ = true;
ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
// Add the remaining shadow targets.
for (int i = 0; i < nof_escapes; i++) {
shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
}
// Generate code for the statements in the try block.
VisitStatementsAndSpill(node->try_block()->statements());
// Stop the introduced shadowing and count the number of required unlinks.
// After shadowing stops, the original targets are unshadowed and the
// ShadowTargets represent the formerly shadowing targets.
int nof_unlinks = 0;
for (int i = 0; i < shadows.length(); i++) {
shadows[i]->StopShadowing();
if (shadows[i]->is_linked()) nof_unlinks++;
}
function_return_is_shadowed_ = function_return_was_shadowed;
// Get an external reference to the handler address.
ExternalReference handler_address(Top::k_handler_address);
// If we can fall off the end of the try block, unlink from the try
// chain and set the state on the frame to FALLING.
if (has_valid_frame()) {
// The next handler address is on top of the frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
// Fake a top of stack value (unneeded when FALLING) and set the
// state in ecx, then jump around the unlink blocks if any.
frame_->EmitPush(Immediate(Factory::undefined_value()));
__ Set(ecx, Immediate(Smi::FromInt(FALLING)));
if (nof_unlinks > 0) {
finally_block.Jump();
}
}
// Generate code to unlink and set the state for the (formerly)
// shadowing targets that have been jumped to.
for (int i = 0; i < shadows.length(); i++) {
if (shadows[i]->is_linked()) {
// If we have come from the shadowed return, the return value is
// on the virtual frame. We must preserve it until it is
// pushed.
if (i == kReturnShadowIndex) {
Result return_value;
shadows[i]->Bind(&return_value);
return_value.ToRegister(eax);
} else {
shadows[i]->Bind();
}
// Because we can be jumping here (to spilled code) from
// unspilled code, we need to reestablish a spilled frame at
// this block.
frame_->SpillAll();
// Reload sp from the top handler, because some statements that
// we break from (eg, for...in) may have left stuff on the
// stack.
__ mov(esp, Operand::StaticVariable(handler_address));
frame_->Forget(frame_->height() - handler_height);
// Unlink this handler and drop it from the frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (i == kReturnShadowIndex) {
// If this target shadowed the function return, materialize
// the return value on the stack.
frame_->EmitPush(eax);
} else {
// Fake TOS for targets that shadowed breaks and continues.
frame_->EmitPush(Immediate(Factory::undefined_value()));
}
__ Set(ecx, Immediate(Smi::FromInt(JUMPING + i)));
if (--nof_unlinks > 0) {
// If this is not the last unlink block, jump around the next.
finally_block.Jump();
}
}
}
// --- Finally block ---
finally_block.Bind();
// Push the state on the stack.
frame_->EmitPush(ecx);
// We keep two elements on the stack - the (possibly faked) result
// and the state - while evaluating the finally block.
//
// Generate code for the statements in the finally block.
VisitStatementsAndSpill(node->finally_block()->statements());
if (has_valid_frame()) {
// Restore state and return value or faked TOS.
frame_->EmitPop(ecx);
frame_->EmitPop(eax);
}
// Generate code to jump to the right destination for all used
// formerly shadowing targets. Deallocate each shadow target.
for (int i = 0; i < shadows.length(); i++) {
if (has_valid_frame() && shadows[i]->is_bound()) {
BreakTarget* original = shadows[i]->other_target();
__ cmp(Operand(ecx), Immediate(Smi::FromInt(JUMPING + i)));
if (i == kReturnShadowIndex) {
// The return value is (already) in eax.
Result return_value = allocator_->Allocate(eax);
ASSERT(return_value.is_valid());
if (function_return_is_shadowed_) {
original->Branch(equal, &return_value);
} else {
// Branch around the preparation for return which may emit
// code.
JumpTarget skip;
skip.Branch(not_equal);
frame_->PrepareForReturn();
original->Jump(&return_value);
skip.Bind();
}
} else {
original->Branch(equal);
}
}
}
if (has_valid_frame()) {
// Check if we need to rethrow the exception.
JumpTarget exit;
__ cmp(Operand(ecx), Immediate(Smi::FromInt(THROWING)));
exit.Branch(not_equal);
// Rethrow exception.
frame_->EmitPush(eax); // undo pop from above
frame_->CallRuntime(Runtime::kReThrow, 1);
// Done.
exit.Bind();
}
}
void CodeGenerator::VisitDebuggerStatement(DebuggerStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ DebuggerStatement");
CodeForStatementPosition(node);
#ifdef ENABLE_DEBUGGER_SUPPORT
// Spill everything, even constants, to the frame.
frame_->SpillAll();
frame_->DebugBreak();
// Ignore the return value.
#endif
}
Result CodeGenerator::InstantiateBoilerplate(Handle<JSFunction> boilerplate) {
ASSERT(boilerplate->IsBoilerplate());
// The inevitable call will sync frame elements to memory anyway, so
// we do it eagerly to allow us to push the arguments directly into
// place.
frame()->SyncRange(0, frame()->element_count() - 1);
// Use the fast case closure allocation code that allocates in new
// space for nested functions that don't need literals cloning.
if (scope()->is_function_scope() && boilerplate->NumberOfLiterals() == 0) {
FastNewClosureStub stub;
frame()->EmitPush(Immediate(boilerplate));
return frame()->CallStub(&stub, 1);
} else {
// Call the runtime to instantiate the function boilerplate
// object.
frame()->EmitPush(esi);
frame()->EmitPush(Immediate(boilerplate));
return frame()->CallRuntime(Runtime::kNewClosure, 2);
}
}
void CodeGenerator::VisitFunctionLiteral(FunctionLiteral* node) {
Comment cmnt(masm_, "[ FunctionLiteral");
// Build the function boilerplate and instantiate it.
Handle<JSFunction> boilerplate =
Compiler::BuildBoilerplate(node, script(), this);
// Check for stack-overflow exception.
if (HasStackOverflow()) return;
Result result = InstantiateBoilerplate(boilerplate);
frame()->Push(&result);
}
void CodeGenerator::VisitFunctionBoilerplateLiteral(
FunctionBoilerplateLiteral* node) {
Comment cmnt(masm_, "[ FunctionBoilerplateLiteral");
Result result = InstantiateBoilerplate(node->boilerplate());
frame()->Push(&result);
}
void CodeGenerator::VisitConditional(Conditional* node) {
Comment cmnt(masm_, "[ Conditional");
JumpTarget then;
JumpTarget else_;
JumpTarget exit;
ControlDestination dest(&then, &else_, true);
LoadCondition(node->condition(), &dest, true);
if (dest.false_was_fall_through()) {
// The else target was bound, so we compile the else part first.
Load(node->else_expression());
if (then.is_linked()) {
exit.Jump();
then.Bind();
Load(node->then_expression());
}
} else {
// The then target was bound, so we compile the then part first.
Load(node->then_expression());
if (else_.is_linked()) {
exit.Jump();
else_.Bind();
Load(node->else_expression());
}
}
exit.Bind();
}
Result CodeGenerator::LoadFromSlot(Slot* slot, TypeofState typeof_state) {
Result result;
if (slot->type() == Slot::LOOKUP) {
ASSERT(slot->var()->is_dynamic());
JumpTarget slow;
JumpTarget done;
// Generate fast-case code for variables that might be shadowed by
// eval-introduced variables. Eval is used a lot without
// introducing variables. In those cases, we do not want to
// perform a runtime call for all variables in the scope
// containing the eval.
if (slot->var()->mode() == Variable::DYNAMIC_GLOBAL) {
result = LoadFromGlobalSlotCheckExtensions(slot, typeof_state, &slow);
// If there was no control flow to slow, we can exit early.
if (!slow.is_linked()) return result;
done.Jump(&result);
} else if (slot->var()->mode() == Variable::DYNAMIC_LOCAL) {
Slot* potential_slot = slot->var()->local_if_not_shadowed()->slot();
// Only generate the fast case for locals that rewrite to slots.
// This rules out argument loads.
if (potential_slot != NULL) {
// Allocate a fresh register to use as a temp in
// ContextSlotOperandCheckExtensions and to hold the result
// value.
result = allocator()->Allocate();
ASSERT(result.is_valid());
__ mov(result.reg(),
ContextSlotOperandCheckExtensions(potential_slot,
result,
&slow));
if (potential_slot->var()->mode() == Variable::CONST) {
__ cmp(result.reg(), Factory::the_hole_value());
done.Branch(not_equal, &result);
__ mov(result.reg(), Factory::undefined_value());
}
// There is always control flow to slow from
// ContextSlotOperandCheckExtensions so we have to jump around
// it.
done.Jump(&result);
}
}
slow.Bind();
// A runtime call is inevitable. We eagerly sync frame elements
// to memory so that we can push the arguments directly into place
// on top of the frame.
frame()->SyncRange(0, frame()->element_count() - 1);
frame()->EmitPush(esi);
frame()->EmitPush(Immediate(slot->var()->name()));
if (typeof_state == INSIDE_TYPEOF) {
result =
frame()->CallRuntime(Runtime::kLoadContextSlotNoReferenceError, 2);
} else {
result = frame()->CallRuntime(Runtime::kLoadContextSlot, 2);
}
done.Bind(&result);
return result;
} else if (slot->var()->mode() == Variable::CONST) {
// Const slots may contain 'the hole' value (the constant hasn't been
// initialized yet) which needs to be converted into the 'undefined'
// value.
//
// We currently spill the virtual frame because constants use the
// potentially unsafe direct-frame access of SlotOperand.
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ Load const");
Label exit;
__ mov(ecx, SlotOperand(slot, ecx));
__ cmp(ecx, Factory::the_hole_value());
__ j(not_equal, &exit);
__ mov(ecx, Factory::undefined_value());
__ bind(&exit);
return Result(ecx);
} else if (slot->type() == Slot::PARAMETER) {
frame()->PushParameterAt(slot->index());
return frame()->Pop();
} else if (slot->type() == Slot::LOCAL) {
frame()->PushLocalAt(slot->index());
return frame()->Pop();
} else {
// The other remaining slot types (LOOKUP and GLOBAL) cannot reach
// here.
//
// The use of SlotOperand below is safe for an unspilled frame
// because it will always be a context slot.
ASSERT(slot->type() == Slot::CONTEXT);
result = allocator()->Allocate();
ASSERT(result.is_valid());
__ mov(result.reg(), SlotOperand(slot, result.reg()));
return result;
}
}
Result CodeGenerator::LoadFromSlotCheckForArguments(Slot* slot,
TypeofState state) {
Result result = LoadFromSlot(slot, state);
// Bail out quickly if we're not using lazy arguments allocation.
if (ArgumentsMode() != LAZY_ARGUMENTS_ALLOCATION) return result;
// ... or if the slot isn't a non-parameter arguments slot.
if (slot->type() == Slot::PARAMETER || !slot->is_arguments()) return result;
// If the loaded value is a constant, we know if the arguments
// object has been lazily loaded yet.
if (result.is_constant()) {
if (result.handle()->IsTheHole()) {
result.Unuse();
return StoreArgumentsObject(false);
} else {
return result;
}
}
// The loaded value is in a register. If it is the sentinel that
// indicates that we haven't loaded the arguments object yet, we
// need to do it now.
JumpTarget exit;
__ cmp(Operand(result.reg()), Immediate(Factory::the_hole_value()));
exit.Branch(not_equal, &result);
result.Unuse();
result = StoreArgumentsObject(false);
exit.Bind(&result);
return result;
}
Result CodeGenerator::LoadFromGlobalSlotCheckExtensions(
Slot* slot,
TypeofState typeof_state,
JumpTarget* slow) {
// Check that no extension objects have been created by calls to
// eval from the current scope to the global scope.
Register context = esi;
Result tmp = allocator_->Allocate();
ASSERT(tmp.is_valid()); // All non-reserved registers were available.
Scope* s = scope();
while (s != NULL) {
if (s->num_heap_slots() > 0) {
if (s->calls_eval()) {
// Check that extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
Immediate(0));
slow->Branch(not_equal, not_taken);
}
// Load next context in chain.
__ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
context = tmp.reg();
}
// If no outer scope calls eval, we do not need to check more
// context extensions. If we have reached an eval scope, we check
// all extensions from this point.
if (!s->outer_scope_calls_eval() || s->is_eval_scope()) break;
s = s->outer_scope();
}
if (s != NULL && s->is_eval_scope()) {
// Loop up the context chain. There is no frame effect so it is
// safe to use raw labels here.
Label next, fast;
if (!context.is(tmp.reg())) {
__ mov(tmp.reg(), context);
}
__ bind(&next);
// Terminate at global context.
__ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
Immediate(Factory::global_context_map()));
__ j(equal, &fast);
// Check that extension is NULL.
__ cmp(ContextOperand(tmp.reg(), Context::EXTENSION_INDEX), Immediate(0));
slow->Branch(not_equal, not_taken);
// Load next context in chain.
__ mov(tmp.reg(), ContextOperand(tmp.reg(), Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
__ jmp(&next);
__ bind(&fast);
}
tmp.Unuse();
// All extension objects were empty and it is safe to use a global
// load IC call.
// The register allocator prefers eax if it is free, so the code generator
// will load the global object directly into eax, which is where the LoadIC
// expects it.
frame_->Spill(eax);
LoadGlobal();
frame_->Push(slot->var()->name());
RelocInfo::Mode mode = (typeof_state == INSIDE_TYPEOF)
? RelocInfo::CODE_TARGET
: RelocInfo::CODE_TARGET_CONTEXT;
Result answer = frame_->CallLoadIC(mode);
// A test eax instruction following the call signals that the inobject
// property case was inlined. Ensure that there is not a test eax
// instruction here.
__ nop();
return answer;
}
void CodeGenerator::StoreToSlot(Slot* slot, InitState init_state) {
if (slot->type() == Slot::LOOKUP) {
ASSERT(slot->var()->is_dynamic());
// For now, just do a runtime call. Since the call is inevitable,
// we eagerly sync the virtual frame so we can directly push the
// arguments into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(slot->var()->name()));
Result value;
if (init_state == CONST_INIT) {
// Same as the case for a normal store, but ignores attribute
// (e.g. READ_ONLY) of context slot so that we can initialize const
// properties (introduced via eval("const foo = (some expr);")). Also,
// uses the current function context instead of the top context.
//
// Note that we must declare the foo upon entry of eval(), via a
// context slot declaration, but we cannot initialize it at the same
// time, because the const declaration may be at the end of the eval
// code (sigh...) and the const variable may have been used before
// (where its value is 'undefined'). Thus, we can only do the
// initialization when we actually encounter the expression and when
// the expression operands are defined and valid, and thus we need the
// split into 2 operations: declaration of the context slot followed
// by initialization.
value = frame_->CallRuntime(Runtime::kInitializeConstContextSlot, 3);
} else {
value = frame_->CallRuntime(Runtime::kStoreContextSlot, 3);
}
// Storing a variable must keep the (new) value on the expression
// stack. This is necessary for compiling chained assignment
// expressions.
frame_->Push(&value);
} else {
ASSERT(!slot->var()->is_dynamic());
JumpTarget exit;
if (init_state == CONST_INIT) {
ASSERT(slot->var()->mode() == Variable::CONST);
// Only the first const initialization must be executed (the slot
// still contains 'the hole' value). When the assignment is executed,
// the code is identical to a normal store (see below).
//
// We spill the frame in the code below because the direct-frame
// access of SlotOperand is potentially unsafe with an unspilled
// frame.
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ Init const");
__ mov(ecx, SlotOperand(slot, ecx));
__ cmp(ecx, Factory::the_hole_value());
exit.Branch(not_equal);
}
// We must execute the store. Storing a variable must keep the (new)
// value on the stack. This is necessary for compiling assignment
// expressions.
//
// Note: We will reach here even with slot->var()->mode() ==
// Variable::CONST because of const declarations which will initialize
// consts to 'the hole' value and by doing so, end up calling this code.
if (slot->type() == Slot::PARAMETER) {
frame_->StoreToParameterAt(slot->index());
} else if (slot->type() == Slot::LOCAL) {
frame_->StoreToLocalAt(slot->index());
} else {
// The other slot types (LOOKUP and GLOBAL) cannot reach here.
//
// The use of SlotOperand below is safe for an unspilled frame
// because the slot is a context slot.
ASSERT(slot->type() == Slot::CONTEXT);
frame_->Dup();
Result value = frame_->Pop();
value.ToRegister();
Result start = allocator_->Allocate();
ASSERT(start.is_valid());
__ mov(SlotOperand(slot, start.reg()), value.reg());
// RecordWrite may destroy the value registers.
//
// TODO(204): Avoid actually spilling when the value is not
// needed (probably the common case).
frame_->Spill(value.reg());
int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ RecordWrite(start.reg(), offset, value.reg(), temp.reg());
// The results start, value, and temp are unused by going out of
// scope.
}
exit.Bind();
}
}
void CodeGenerator::VisitSlot(Slot* node) {
Comment cmnt(masm_, "[ Slot");
Result result = LoadFromSlotCheckForArguments(node, NOT_INSIDE_TYPEOF);
frame()->Push(&result);
}
void CodeGenerator::VisitVariableProxy(VariableProxy* node) {
Comment cmnt(masm_, "[ VariableProxy");
Variable* var = node->var();
Expression* expr = var->rewrite();
if (expr != NULL) {
Visit(expr);
} else {
ASSERT(var->is_global());
Reference ref(this, node);
ref.GetValue();
}
}
void CodeGenerator::VisitLiteral(Literal* node) {
Comment cmnt(masm_, "[ Literal");
frame_->Push(node->handle());
}
void CodeGenerator::PushUnsafeSmi(Handle<Object> value) {
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ push(Immediate(bits & 0x0000FFFF));
__ or_(Operand(esp, 0), Immediate(bits & 0xFFFF0000));
}
void CodeGenerator::StoreUnsafeSmiToLocal(int offset, Handle<Object> value) {
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ mov(Operand(ebp, offset), Immediate(bits & 0x0000FFFF));
__ or_(Operand(ebp, offset), Immediate(bits & 0xFFFF0000));
}
void CodeGenerator::MoveUnsafeSmi(Register target, Handle<Object> value) {
ASSERT(target.is_valid());
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ Set(target, Immediate(bits & 0x0000FFFF));
__ or_(target, bits & 0xFFFF0000);
}
bool CodeGenerator::IsUnsafeSmi(Handle<Object> value) {
if (!value->IsSmi()) return false;
int int_value = Smi::cast(*value)->value();
return !is_intn(int_value, kMaxSmiInlinedBits);
}
// Materialize the regexp literal 'node' in the literals array
// 'literals' of the function. Leave the regexp boilerplate in
// 'boilerplate'.
class DeferredRegExpLiteral: public DeferredCode {
public:
DeferredRegExpLiteral(Register boilerplate,
Register literals,
RegExpLiteral* node)
: boilerplate_(boilerplate), literals_(literals), node_(node) {
set_comment("[ DeferredRegExpLiteral");
}
void Generate();
private:
Register boilerplate_;
Register literals_;
RegExpLiteral* node_;
};
void DeferredRegExpLiteral::Generate() {
// Since the entry is undefined we call the runtime system to
// compute the literal.
// Literal array (0).
__ push(literals_);
// Literal index (1).
__ push(Immediate(Smi::FromInt(node_->literal_index())));
// RegExp pattern (2).
__ push(Immediate(node_->pattern()));
// RegExp flags (3).
__ push(Immediate(node_->flags()));
__ CallRuntime(Runtime::kMaterializeRegExpLiteral, 4);
if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
}
void CodeGenerator::VisitRegExpLiteral(RegExpLiteral* node) {
Comment cmnt(masm_, "[ RegExp Literal");
// Retrieve the literals array and check the allocated entry. Begin
// with a writable copy of the function of this activation in a
// register.
frame_->PushFunction();
Result literals = frame_->Pop();
literals.ToRegister();
frame_->Spill(literals.reg());
// Load the literals array of the function.
__ mov(literals.reg(),
FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
// Load the literal at the ast saved index.
Result boilerplate = allocator_->Allocate();
ASSERT(boilerplate.is_valid());
int literal_offset =
FixedArray::kHeaderSize + node->literal_index() * kPointerSize;
__ mov(boilerplate.reg(), FieldOperand(literals.reg(), literal_offset));
// Check whether we need to materialize the RegExp object. If so,
// jump to the deferred code passing the literals array.
DeferredRegExpLiteral* deferred =
new DeferredRegExpLiteral(boilerplate.reg(), literals.reg(), node);
__ cmp(boilerplate.reg(), Factory::undefined_value());
deferred->Branch(equal);
deferred->BindExit();
literals.Unuse();
// Push the boilerplate object.
frame_->Push(&boilerplate);
}
void CodeGenerator::VisitObjectLiteral(ObjectLiteral* node) {
Comment cmnt(masm_, "[ ObjectLiteral");
// Load a writable copy of the function of this activation in a
// register.
frame_->PushFunction();
Result literals = frame_->Pop();
literals.ToRegister();
frame_->Spill(literals.reg());
// Load the literals array of the function.
__ mov(literals.reg(),
FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
// Literal array.
frame_->Push(&literals);
// Literal index.
frame_->Push(Smi::FromInt(node->literal_index()));
// Constant properties.
frame_->Push(node->constant_properties());
Result clone;
if (node->depth() > 1) {
clone = frame_->CallRuntime(Runtime::kCreateObjectLiteral, 3);
} else {
clone = frame_->CallRuntime(Runtime::kCreateObjectLiteralShallow, 3);
}
frame_->Push(&clone);
for (int i = 0; i < node->properties()->length(); i++) {
ObjectLiteral::Property* property = node->properties()->at(i);
switch (property->kind()) {
case ObjectLiteral::Property::CONSTANT:
break;
case ObjectLiteral::Property::MATERIALIZED_LITERAL:
if (CompileTimeValue::IsCompileTimeValue(property->value())) break;
// else fall through.
case ObjectLiteral::Property::COMPUTED: {
Handle<Object> key(property->key()->handle());
if (key->IsSymbol()) {
// Duplicate the object as the IC receiver.
frame_->Dup();
Load(property->value());
Result dummy = frame_->CallStoreIC(Handle<String>::cast(key), false);
dummy.Unuse();
break;
}
// Fall through
}
case ObjectLiteral::Property::PROTOTYPE: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kSetProperty, 3);
// Ignore the result.
break;
}
case ObjectLiteral::Property::SETTER: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
frame_->Push(Smi::FromInt(1));
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
// Ignore the result.
break;
}
case ObjectLiteral::Property::GETTER: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
frame_->Push(Smi::FromInt(0));
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
// Ignore the result.
break;
}
default: UNREACHABLE();
}
}
}
void CodeGenerator::VisitArrayLiteral(ArrayLiteral* node) {
Comment cmnt(masm_, "[ ArrayLiteral");
// Load a writable copy of the function of this activation in a
// register.
frame_->PushFunction();
Result literals = frame_->Pop();
literals.ToRegister();
frame_->Spill(literals.reg());
// Load the literals array of the function.
__ mov(literals.reg(),
FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
frame_->Push(&literals);
frame_->Push(Smi::FromInt(node->literal_index()));
frame_->Push(node->constant_elements());
int length = node->values()->length();
Result clone;
if (node->depth() > 1) {
clone = frame_->CallRuntime(Runtime::kCreateArrayLiteral, 3);
} else if (length > FastCloneShallowArrayStub::kMaximumLength) {
clone = frame_->CallRuntime(Runtime::kCreateArrayLiteralShallow, 3);
} else {
FastCloneShallowArrayStub stub(length);
clone = frame_->CallStub(&stub, 3);
}
frame_->Push(&clone);
// Generate code to set the elements in the array that are not
// literals.
for (int i = 0; i < length; i++) {
Expression* value = node->values()->at(i);
// If value is a literal the property value is already set in the
// boilerplate object.
if (value->AsLiteral() != NULL) continue;
// If value is a materialized literal the property value is already set
// in the boilerplate object if it is simple.
if (CompileTimeValue::IsCompileTimeValue(value)) continue;
// The property must be set by generated code.
Load(value);
// Get the property value off the stack.
Result prop_value = frame_->Pop();
prop_value.ToRegister();
// Fetch the array literal while leaving a copy on the stack and
// use it to get the elements array.
frame_->Dup();
Result elements = frame_->Pop();
elements.ToRegister();
frame_->Spill(elements.reg());
// Get the elements array.
__ mov(elements.reg(),
FieldOperand(elements.reg(), JSObject::kElementsOffset));
// Write to the indexed properties array.
int offset = i * kPointerSize + FixedArray::kHeaderSize;
__ mov(FieldOperand(elements.reg(), offset), prop_value.reg());
// Update the write barrier for the array address.
frame_->Spill(prop_value.reg()); // Overwritten by the write barrier.
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
__ RecordWrite(elements.reg(), offset, prop_value.reg(), scratch.reg());
}
}
void CodeGenerator::VisitCatchExtensionObject(CatchExtensionObject* node) {
ASSERT(!in_spilled_code());
// Call runtime routine to allocate the catch extension object and
// assign the exception value to the catch variable.
Comment cmnt(masm_, "[ CatchExtensionObject");
Load(node->key());
Load(node->value());
Result result =
frame_->CallRuntime(Runtime::kCreateCatchExtensionObject, 2);
frame_->Push(&result);
}
void CodeGenerator::EmitSlotAssignment(Assignment* node) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Comment cmnt(masm(), "[ Variable Assignment");
Variable* var = node->target()->AsVariableProxy()->AsVariable();
ASSERT(var != NULL);
Slot* slot = var->slot();
ASSERT(slot != NULL);
// Evaluate the right-hand side.
if (node->is_compound()) {
Result result = LoadFromSlotCheckForArguments(slot, NOT_INSIDE_TYPEOF);
frame()->Push(&result);
Load(node->value());
bool overwrite_value =
(node->value()->AsBinaryOperation() != NULL &&
node->value()->AsBinaryOperation()->ResultOverwriteAllowed());
GenericBinaryOperation(node->binary_op(),
node->type(),
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
Load(node->value());
}
// Perform the assignment.
if (var->mode() != Variable::CONST || node->op() == Token::INIT_CONST) {
CodeForSourcePosition(node->position());
StoreToSlot(slot,
node->op() == Token::INIT_CONST ? CONST_INIT : NOT_CONST_INIT);
}
ASSERT(frame()->height() == original_height + 1);
}
void CodeGenerator::EmitNamedPropertyAssignment(Assignment* node) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Comment cmnt(masm(), "[ Named Property Assignment");
Variable* var = node->target()->AsVariableProxy()->AsVariable();
Property* prop = node->target()->AsProperty();
ASSERT(var == NULL || (prop == NULL && var->is_global()));
// Initialize name and evaluate the receiver subexpression if necessary.
Handle<String> name;
bool is_trivial_receiver = false;
if (var != NULL) {
name = var->name();
} else {
Literal* lit = prop->key()->AsLiteral();
ASSERT_NOT_NULL(lit);
name = Handle<String>::cast(lit->handle());
// Do not materialize the receiver on the frame if it is trivial.
is_trivial_receiver = prop->obj()->IsTrivial();
if (!is_trivial_receiver) Load(prop->obj());
}
if (node->starts_initialization_block()) {
ASSERT_EQ(NULL, var);
// Change to slow case in the beginning of an initialization block to
// avoid the quadratic behavior of repeatedly adding fast properties.
if (is_trivial_receiver) {
frame()->Push(prop->obj());
} else {
frame()->Dup();
}
Result ignored = frame()->CallRuntime(Runtime::kToSlowProperties, 1);
}
if (node->ends_initialization_block() && !is_trivial_receiver) {
// Add an extra copy of the receiver to the frame, so that it can be
// converted back to fast case after the assignment.
frame()->Dup();
}
// Evaluate the right-hand side.
if (node->is_compound()) {
if (is_trivial_receiver) {
frame()->Push(prop->obj());
} else if (var != NULL) {
// The LoadIC stub expects the object in eax.
// Freeing eax causes the code generator to load the global into it.
frame_->Spill(eax);
LoadGlobal();
} else {
frame()->Dup();
}
Result value = EmitNamedLoad(name, var != NULL);
frame()->Push(&value);
Load(node->value());
bool overwrite_value =
(node->value()->AsBinaryOperation() != NULL &&
node->value()->AsBinaryOperation()->ResultOverwriteAllowed());
GenericBinaryOperation(node->binary_op(),
node->type(),
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
Load(node->value());
}
// Perform the assignment. It is safe to ignore constants here.
ASSERT(var == NULL || var->mode() != Variable::CONST);
ASSERT_NE(Token::INIT_CONST, node->op());
if (is_trivial_receiver) {
Result value = frame()->Pop();
frame()->Push(prop->obj());
frame()->Push(&value);
}
CodeForSourcePosition(node->position());
bool is_contextual = (var != NULL);
Result answer = EmitNamedStore(name, is_contextual);
frame()->Push(&answer);
if (node->ends_initialization_block()) {
ASSERT_EQ(NULL, var);
// The argument to the runtime call is the receiver.
if (is_trivial_receiver) {
frame()->Push(prop->obj());
} else {
// A copy of the receiver is below the value of the assignment. Swap
// the receiver and the value of the assignment expression.
Result result = frame()->Pop();
Result receiver = frame()->Pop();
frame()->Push(&result);
frame()->Push(&receiver);
}
Result ignored = frame_->CallRuntime(Runtime::kToFastProperties, 1);
}
ASSERT_EQ(frame()->height(), original_height + 1);
}
void CodeGenerator::EmitKeyedPropertyAssignment(Assignment* node) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Comment cmnt(masm_, "[ Named Property Assignment");
Property* prop = node->target()->AsProperty();
ASSERT_NOT_NULL(prop);
// Evaluate the receiver subexpression.
Load(prop->obj());
if (node->starts_initialization_block()) {
// Change to slow case in the beginning of an initialization block to
// avoid the quadratic behavior of repeatedly adding fast properties.
frame_->Dup();
Result ignored = frame_->CallRuntime(Runtime::kToSlowProperties, 1);
}
if (node->ends_initialization_block()) {
// Add an extra copy of the receiver to the frame, so that it can be
// converted back to fast case after the assignment.
frame_->Dup();
}
// Evaluate the key subexpression.
Load(prop->key());
// Evaluate the right-hand side.
if (node->is_compound()) {
// Duplicate receiver and key.
frame()->PushElementAt(1);
frame()->PushElementAt(1);
Result value = EmitKeyedLoad();
frame()->Push(&value);
Load(node->value());
bool overwrite_value =
(node->value()->AsBinaryOperation() != NULL &&
node->value()->AsBinaryOperation()->ResultOverwriteAllowed());
GenericBinaryOperation(node->binary_op(),
node->type(),
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
Load(node->value());
}
// Perform the assignment. It is safe to ignore constants here.
ASSERT(node->op() != Token::INIT_CONST);
CodeForSourcePosition(node->position());
Result answer = EmitKeyedStore(prop->key()->type());
frame()->Push(&answer);
if (node->ends_initialization_block()) {
// The argument to the runtime call is the extra copy of the receiver,
// which is below the value of the assignment. Swap the receiver and
// the value of the assignment expression.
Result result = frame()->Pop();
Result receiver = frame()->Pop();
frame()->Push(&result);
frame()->Push(&receiver);
Result ignored = frame_->CallRuntime(Runtime::kToFastProperties, 1);
}
ASSERT(frame()->height() == original_height + 1);
}
void CodeGenerator::VisitAssignment(Assignment* node) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Variable* var = node->target()->AsVariableProxy()->AsVariable();
Property* prop = node->target()->AsProperty();
if (var != NULL && !var->is_global()) {
EmitSlotAssignment(node);
} else if ((prop != NULL && prop->key()->IsPropertyName()) ||
(var != NULL && var->is_global())) {
// Properties whose keys are property names and global variables are
// treated as named property references. We do not need to consider
// global 'this' because it is not a valid left-hand side.
EmitNamedPropertyAssignment(node);
} else if (prop != NULL) {
// Other properties (including rewritten parameters for a function that
// uses arguments) are keyed property assignments.
EmitKeyedPropertyAssignment(node);
} else {
// Invalid left-hand side.
Load(node->target());
Result result = frame()->CallRuntime(Runtime::kThrowReferenceError, 1);
// The runtime call doesn't actually return but the code generator will
// still generate code and expects a certain frame height.
frame()->Push(&result);
}
ASSERT(frame()->height() == original_height + 1);
}
void CodeGenerator::VisitThrow(Throw* node) {
Comment cmnt(masm_, "[ Throw");
Load(node->exception());
Result result = frame_->CallRuntime(Runtime::kThrow, 1);
frame_->Push(&result);
}
void CodeGenerator::VisitProperty(Property* node) {
Comment cmnt(masm_, "[ Property");
Reference property(this, node);
property.GetValue();
}
void CodeGenerator::VisitCall(Call* node) {
Comment cmnt(masm_, "[ Call");
Expression* function = node->expression();
ZoneList<Expression*>* args = node->arguments();
// Check if the function is a variable or a property.
Variable* var = function->AsVariableProxy()->AsVariable();
Property* property = function->AsProperty();
// ------------------------------------------------------------------------
// Fast-case: Use inline caching.
// ---
// According to ECMA-262, section 11.2.3, page 44, the function to call
// must be resolved after the arguments have been evaluated. The IC code
// automatically handles this by loading the arguments before the function
// is resolved in cache misses (this also holds for megamorphic calls).
// ------------------------------------------------------------------------
if (var != NULL && var->is_possibly_eval()) {
// ----------------------------------
// JavaScript example: 'eval(arg)' // eval is not known to be shadowed
// ----------------------------------
// In a call to eval, we first call %ResolvePossiblyDirectEval to
// resolve the function we need to call and the receiver of the
// call. Then we call the resolved function using the given
// arguments.
// Prepare the stack for the call to the resolved function.
Load(function);
// Allocate a frame slot for the receiver.
frame_->Push(Factory::undefined_value());
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Prepare the stack for the call to ResolvePossiblyDirectEval.
frame_->PushElementAt(arg_count + 1);
if (arg_count > 0) {
frame_->PushElementAt(arg_count);
} else {
frame_->Push(Factory::undefined_value());
}
// Push the receiver.
frame_->PushParameterAt(-1);
// Resolve the call.
Result result =
frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 3);
// The runtime call returns a pair of values in eax (function) and
// edx (receiver). Touch up the stack with the right values.
Result receiver = allocator_->Allocate(edx);
frame_->SetElementAt(arg_count + 1, &result);
frame_->SetElementAt(arg_count, &receiver);
receiver.Unuse();
// Call the function.
CodeForSourcePosition(node->position());
InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
CallFunctionStub call_function(arg_count, in_loop, RECEIVER_MIGHT_BE_VALUE);
result = frame_->CallStub(&call_function, arg_count + 1);
// Restore the context and overwrite the function on the stack with
// the result.
frame_->RestoreContextRegister();
frame_->SetElementAt(0, &result);
} else if (var != NULL && !var->is_this() && var->is_global()) {
// ----------------------------------
// JavaScript example: 'foo(1, 2, 3)' // foo is global
// ----------------------------------
// Pass the global object as the receiver and let the IC stub
// patch the stack to use the global proxy as 'this' in the
// invoked function.
LoadGlobal();
// Load the arguments.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Push the name of the function onto the frame.
frame_->Push(var->name());
// Call the IC initialization code.
CodeForSourcePosition(node->position());
Result result = frame_->CallCallIC(RelocInfo::CODE_TARGET_CONTEXT,
arg_count,
loop_nesting());
frame_->RestoreContextRegister();
frame_->Push(&result);
} else if (var != NULL && var->slot() != NULL &&
var->slot()->type() == Slot::LOOKUP) {
// ----------------------------------
// JavaScript example: 'with (obj) foo(1, 2, 3)' // foo is in obj
// ----------------------------------
// Load the function from the context. Sync the frame so we can
// push the arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(var->name()));
frame_->CallRuntime(Runtime::kLoadContextSlot, 2);
// The runtime call returns a pair of values in eax and edx. The
// looked-up function is in eax and the receiver is in edx. These
// register references are not ref counted here. We spill them
// eagerly since they are arguments to an inevitable call (and are
// not sharable by the arguments).
ASSERT(!allocator()->is_used(eax));
frame_->EmitPush(eax);
// Load the receiver.
ASSERT(!allocator()->is_used(edx));
frame_->EmitPush(edx);
// Call the function.
CallWithArguments(args, NO_CALL_FUNCTION_FLAGS, node->position());
} else if (property != NULL) {
// Check if the key is a literal string.
Literal* literal = property->key()->AsLiteral();
if (literal != NULL && literal->handle()->IsSymbol()) {
// ------------------------------------------------------------------
// JavaScript example: 'object.foo(1, 2, 3)' or 'map["key"](1, 2, 3)'
// ------------------------------------------------------------------
Handle<String> name = Handle<String>::cast(literal->handle());
if (ArgumentsMode() == LAZY_ARGUMENTS_ALLOCATION &&
name->IsEqualTo(CStrVector("apply")) &&
args->length() == 2 &&
args->at(1)->AsVariableProxy() != NULL &&
args->at(1)->AsVariableProxy()->IsArguments()) {
// Use the optimized Function.prototype.apply that avoids
// allocating lazily allocated arguments objects.
CallApplyLazy(property->obj(),
args->at(0),
args->at(1)->AsVariableProxy(),
node->position());
} else {
// Push the receiver onto the frame.
Load(property->obj());
// Load the arguments.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Push the name of the function onto the frame.
frame_->Push(name);
// Call the IC initialization code.
CodeForSourcePosition(node->position());
Result result =
frame_->CallCallIC(RelocInfo::CODE_TARGET, arg_count,
loop_nesting());
frame_->RestoreContextRegister();
frame_->Push(&result);
}
} else {
// -------------------------------------------
// JavaScript example: 'array[index](1, 2, 3)'
// -------------------------------------------
// Load the function to call from the property through a reference.
// Pass receiver to called function.
if (property->is_synthetic()) {
Reference ref(this, property);
ref.GetValue();
// Use global object as receiver.
LoadGlobalReceiver();
} else {
Load(property->obj());
frame()->Dup();
Load(property->key());
Result function = EmitKeyedLoad();
Result receiver = frame_->Pop();
frame_->Push(&function);
frame_->Push(&receiver);
}
// Call the function.
CallWithArguments(args, RECEIVER_MIGHT_BE_VALUE, node->position());
}
} else {
// ----------------------------------
// JavaScript example: 'foo(1, 2, 3)' // foo is not global
// ----------------------------------
// Load the function.
Load(function);
// Pass the global proxy as the receiver.
LoadGlobalReceiver();
// Call the function.
CallWithArguments(args, NO_CALL_FUNCTION_FLAGS, node->position());
}
}
void CodeGenerator::VisitCallNew(CallNew* node) {
Comment cmnt(masm_, "[ CallNew");
// According to ECMA-262, section 11.2.2, page 44, the function
// expression in new calls must be evaluated before the
// arguments. This is different from ordinary calls, where the
// actual function to call is resolved after the arguments have been
// evaluated.
// Compute function to call and use the global object as the
// receiver. There is no need to use the global proxy here because
// it will always be replaced with a newly allocated object.
Load(node->expression());
LoadGlobal();
// Push the arguments ("left-to-right") on the stack.
ZoneList<Expression*>* args = node->arguments();
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Call the construct call builtin that handles allocation and
// constructor invocation.
CodeForSourcePosition(node->position());
Result result = frame_->CallConstructor(arg_count);
// Replace the function on the stack with the result.
frame_->SetElementAt(0, &result);
}
void CodeGenerator::GenerateIsSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask));
value.Unuse();
destination()->Split(zero);
}
void CodeGenerator::GenerateLog(ZoneList<Expression*>* args) {
// Conditionally generate a log call.
// Args:
// 0 (literal string): The type of logging (corresponds to the flags).
// This is used to determine whether or not to generate the log call.
// 1 (string): Format string. Access the string at argument index 2
// with '%2s' (see Logger::LogRuntime for all the formats).
// 2 (array): Arguments to the format string.
ASSERT_EQ(args->length(), 3);
#ifdef ENABLE_LOGGING_AND_PROFILING
if (ShouldGenerateLog(args->at(0))) {
Load(args->at(1));
Load(args->at(2));
frame_->CallRuntime(Runtime::kLog, 2);
}
#endif
// Finally, we're expected to leave a value on the top of the stack.
frame_->Push(Factory::undefined_value());
}
void CodeGenerator::GenerateIsNonNegativeSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask | 0x80000000));
value.Unuse();
destination()->Split(zero);
}
// This generates code that performs a charCodeAt() call or returns
// undefined in order to trigger the slow case, Runtime_StringCharCodeAt.
// It can handle flat, 8 and 16 bit characters and cons strings where the
// answer is found in the left hand branch of the cons. The slow case will
// flatten the string, which will ensure that the answer is in the left hand
// side the next time around.
void CodeGenerator::GenerateFastCharCodeAt(ZoneList<Expression*>* args) {
Comment(masm_, "[ GenerateFastCharCodeAt");
ASSERT(args->length() == 2);
Label slow_case;
Label end;
Label not_a_flat_string;
Label try_again_with_new_string;
Label ascii_string;
Label got_char_code;
Load(args->at(0));
Load(args->at(1));
Result index = frame_->Pop();
Result object = frame_->Pop();
// Get register ecx to use as shift amount later.
Result shift_amount;
if (object.is_register() && object.reg().is(ecx)) {
Result fresh = allocator_->Allocate();
shift_amount = object;
object = fresh;
__ mov(object.reg(), ecx);
}
if (index.is_register() && index.reg().is(ecx)) {
Result fresh = allocator_->Allocate();
shift_amount = index;
index = fresh;
__ mov(index.reg(), ecx);
}
// There could be references to ecx in the frame. Allocating will
// spill them, otherwise spill explicitly.
if (shift_amount.is_valid()) {
frame_->Spill(ecx);
} else {
shift_amount = allocator()->Allocate(ecx);
}
ASSERT(shift_amount.is_register());
ASSERT(shift_amount.reg().is(ecx));
ASSERT(allocator_->count(ecx) == 1);
// We will mutate the index register and possibly the object register.
// The case where they are somehow the same register is handled
// because we only mutate them in the case where the receiver is a
// heap object and the index is not.
object.ToRegister();
index.ToRegister();
frame_->Spill(object.reg());
frame_->Spill(index.reg());
// We need a single extra temporary register.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// There is no virtual frame effect from here up to the final result
// push.
// If the receiver is a smi trigger the slow case.
ASSERT(kSmiTag == 0);
__ test(object.reg(), Immediate(kSmiTagMask));
__ j(zero, &slow_case);
// If the index is negative or non-smi trigger the slow case.
ASSERT(kSmiTag == 0);
__ test(index.reg(), Immediate(kSmiTagMask | 0x80000000));
__ j(not_zero, &slow_case);
// Untag the index.
__ SmiUntag(index.reg());
__ bind(&try_again_with_new_string);
// Fetch the instance type of the receiver into ecx.
__ mov(ecx, FieldOperand(object.reg(), HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
// If the receiver is not a string trigger the slow case.
__ test(ecx, Immediate(kIsNotStringMask));
__ j(not_zero, &slow_case);
// Fetch the length field into the temporary register.
__ mov(temp.reg(), FieldOperand(object.reg(), String::kLengthOffset));
// Check for index out of range.
__ cmp(index.reg(), Operand(temp.reg()));
__ j(greater_equal, &slow_case);
// Reload the instance type (into the temp register this time)..
__ mov(temp.reg(), FieldOperand(object.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
// We need special handling for non-flat strings.
ASSERT(kSeqStringTag == 0);
__ test(temp.reg(), Immediate(kStringRepresentationMask));
__ j(not_zero, ¬_a_flat_string);
// Check for 1-byte or 2-byte string.
__ test(temp.reg(), Immediate(kStringEncodingMask));
__ j(not_zero, &ascii_string);
// 2-byte string.
// Load the 2-byte character code into the temp register.
__ movzx_w(temp.reg(), FieldOperand(object.reg(),
index.reg(),
times_2,
SeqTwoByteString::kHeaderSize));
__ jmp(&got_char_code);
// ASCII string.
__ bind(&ascii_string);
// Load the byte into the temp register.
__ movzx_b(temp.reg(), FieldOperand(object.reg(),
index.reg(),
times_1,
SeqAsciiString::kHeaderSize));
__ bind(&got_char_code);
__ SmiTag(temp.reg());
__ jmp(&end);
// Handle non-flat strings.
__ bind(¬_a_flat_string);
__ and_(temp.reg(), kStringRepresentationMask);
__ cmp(temp.reg(), kConsStringTag);
__ j(not_equal, &slow_case);
// ConsString.
// Check that the right hand side is the empty string (ie if this is really a
// flat string in a cons string). If that is not the case we would rather go
// to the runtime system now, to flatten the string.
__ mov(temp.reg(), FieldOperand(object.reg(), ConsString::kSecondOffset));
__ cmp(Operand(temp.reg()), Factory::empty_string());
__ j(not_equal, &slow_case);
// Get the first of the two strings.
__ mov(object.reg(), FieldOperand(object.reg(), ConsString::kFirstOffset));
__ jmp(&try_again_with_new_string);
__ bind(&slow_case);
// Move the undefined value into the result register, which will
// trigger the slow case.
__ Set(temp.reg(), Immediate(Factory::undefined_value()));
__ bind(&end);
frame_->Push(&temp);
}
void CodeGenerator::GenerateIsArray(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(equal);
// It is a heap object - get map.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// Check if the object is a JS array or not.
__ CmpObjectType(value.reg(), JS_ARRAY_TYPE, temp.reg());
value.Unuse();
temp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateIsRegExp(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(equal);
// It is a heap object - get map.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// Check if the object is a regexp.
__ CmpObjectType(value.reg(), JS_REGEXP_TYPE, temp.reg());
value.Unuse();
temp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateIsObject(ZoneList<Expression*>* args) {
// This generates a fast version of:
// (typeof(arg) === 'object' || %_ClassOf(arg) == 'RegExp')
ASSERT(args->length() == 1);
Load(args->at(0));
Result obj = frame_->Pop();
obj.ToRegister();
__ test(obj.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
__ cmp(obj.reg(), Factory::null_value());
destination()->true_target()->Branch(equal);
Result map = allocator()->Allocate();
ASSERT(map.is_valid());
__ mov(map.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
// Undetectable objects behave like undefined when tested with typeof.
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kBitFieldOffset));
__ test(map.reg(), Immediate(1 << Map::kIsUndetectable));
destination()->false_target()->Branch(not_zero);
__ mov(map.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
__ cmp(map.reg(), FIRST_JS_OBJECT_TYPE);
destination()->false_target()->Branch(less);
__ cmp(map.reg(), LAST_JS_OBJECT_TYPE);
obj.Unuse();
map.Unuse();
destination()->Split(less_equal);
}
void CodeGenerator::GenerateIsFunction(ZoneList<Expression*>* args) {
// This generates a fast version of:
// (%_ClassOf(arg) === 'Function')
ASSERT(args->length() == 1);
Load(args->at(0));
Result obj = frame_->Pop();
obj.ToRegister();
__ test(obj.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, temp.reg());
obj.Unuse();
temp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateIsUndetectableObject(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result obj = frame_->Pop();
obj.ToRegister();
__ test(obj.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(),
FieldOperand(obj.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(),
FieldOperand(temp.reg(), Map::kBitFieldOffset));
__ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
obj.Unuse();
temp.Unuse();
destination()->Split(not_zero);
}
void CodeGenerator::GenerateIsConstructCall(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
// Get the frame pointer for the calling frame.
Result fp = allocator()->Allocate();
__ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
// Skip the arguments adaptor frame if it exists.
Label check_frame_marker;
__ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(not_equal, &check_frame_marker);
__ mov(fp.reg(), Operand(fp.reg(), StandardFrameConstants::kCallerFPOffset));
// Check the marker in the calling frame.
__ bind(&check_frame_marker);
__ cmp(Operand(fp.reg(), StandardFrameConstants::kMarkerOffset),
Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
fp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateArgumentsLength(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
// ArgumentsAccessStub takes the parameter count as an input argument
// in register eax. Create a constant result for it.
Result count(Handle<Smi>(Smi::FromInt(scope()->num_parameters())));
// Call the shared stub to get to the arguments.length.
ArgumentsAccessStub stub(ArgumentsAccessStub::READ_LENGTH);
Result result = frame_->CallStub(&stub, &count);
frame_->Push(&result);
}
void CodeGenerator::GenerateClassOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
JumpTarget leave, null, function, non_function_constructor;
Load(args->at(0)); // Load the object.
Result obj = frame_->Pop();
obj.ToRegister();
frame_->Spill(obj.reg());
// If the object is a smi, we return null.
__ test(obj.reg(), Immediate(kSmiTagMask));
null.Branch(zero);
// Check that the object is a JS object but take special care of JS
// functions to make sure they have 'Function' as their class.
{ Result tmp = allocator()->Allocate();
__ mov(obj.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
__ movzx_b(tmp.reg(), FieldOperand(obj.reg(), Map::kInstanceTypeOffset));
__ cmp(tmp.reg(), FIRST_JS_OBJECT_TYPE);
null.Branch(less);
// As long as JS_FUNCTION_TYPE is the last instance type and it is
// right after LAST_JS_OBJECT_TYPE, we can avoid checking for
// LAST_JS_OBJECT_TYPE.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
__ cmp(tmp.reg(), JS_FUNCTION_TYPE);
function.Branch(equal);
}
// Check if the constructor in the map is a function.
{ Result tmp = allocator()->Allocate();
__ mov(obj.reg(), FieldOperand(obj.reg(), Map::kConstructorOffset));
__ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, tmp.reg());
non_function_constructor.Branch(not_equal);
}
// The map register now contains the constructor function. Grab the
// instance class name from there.
__ mov(obj.reg(),
FieldOperand(obj.reg(), JSFunction::kSharedFunctionInfoOffset));
__ mov(obj.reg(),
FieldOperand(obj.reg(), SharedFunctionInfo::kInstanceClassNameOffset));
frame_->Push(&obj);
leave.Jump();
// Functions have class 'Function'.
function.Bind();
frame_->Push(Factory::function_class_symbol());
leave.Jump();
// Objects with a non-function constructor have class 'Object'.
non_function_constructor.Bind();
frame_->Push(Factory::Object_symbol());
leave.Jump();
// Non-JS objects have class null.
null.Bind();
frame_->Push(Factory::null_value());
// All done.
leave.Bind();
}
void CodeGenerator::GenerateValueOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
JumpTarget leave;
Load(args->at(0)); // Load the object.
frame_->Dup();
Result object = frame_->Pop();
object.ToRegister();
ASSERT(object.is_valid());
// if (object->IsSmi()) return object.
__ test(object.reg(), Immediate(kSmiTagMask));
leave.Branch(zero, taken);
// It is a heap object - get map.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// if (!object->IsJSValue()) return object.
__ CmpObjectType(object.reg(), JS_VALUE_TYPE, temp.reg());
leave.Branch(not_equal, not_taken);
__ mov(temp.reg(), FieldOperand(object.reg(), JSValue::kValueOffset));
object.Unuse();
frame_->SetElementAt(0, &temp);
leave.Bind();
}
void CodeGenerator::GenerateSetValueOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 2);
JumpTarget leave;
Load(args->at(0)); // Load the object.
Load(args->at(1)); // Load the value.
Result value = frame_->Pop();
Result object = frame_->Pop();
value.ToRegister();
object.ToRegister();
// if (object->IsSmi()) return value.
__ test(object.reg(), Immediate(kSmiTagMask));
leave.Branch(zero, &value, taken);
// It is a heap object - get its map.
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
// if (!object->IsJSValue()) return value.
__ CmpObjectType(object.reg(), JS_VALUE_TYPE, scratch.reg());
leave.Branch(not_equal, &value, not_taken);
// Store the value.
__ mov(FieldOperand(object.reg(), JSValue::kValueOffset), value.reg());
// Update the write barrier. Save the value as it will be
// overwritten by the write barrier code and is needed afterward.
Result duplicate_value = allocator_->Allocate();
ASSERT(duplicate_value.is_valid());
__ mov(duplicate_value.reg(), value.reg());
// The object register is also overwritten by the write barrier and
// possibly aliased in the frame.
frame_->Spill(object.reg());
__ RecordWrite(object.reg(), JSValue::kValueOffset, duplicate_value.reg(),
scratch.reg());
object.Unuse();
scratch.Unuse();
duplicate_value.Unuse();
// Leave.
leave.Bind(&value);
frame_->Push(&value);
}
void CodeGenerator::GenerateArgumentsAccess(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
// ArgumentsAccessStub expects the key in edx and the formal
// parameter count in eax.
Load(args->at(0));
Result key = frame_->Pop();
// Explicitly create a constant result.
Result count(Handle<Smi>(Smi::FromInt(scope()->num_parameters())));
// Call the shared stub to get to arguments[key].
ArgumentsAccessStub stub(ArgumentsAccessStub::READ_ELEMENT);
Result result = frame_->CallStub(&stub, &key, &count);
frame_->Push(&result);
}
void CodeGenerator::GenerateObjectEquals(ZoneList<Expression*>* args) {
ASSERT(args->length() == 2);
// Load the two objects into registers and perform the comparison.
Load(args->at(0));
Load(args->at(1));
Result right = frame_->Pop();
Result left = frame_->Pop();
right.ToRegister();
left.ToRegister();
__ cmp(right.reg(), Operand(left.reg()));
right.Unuse();
left.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateGetFramePointer(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
ASSERT(kSmiTag == 0); // EBP value is aligned, so it should look like Smi.
Result ebp_as_smi = allocator_->Allocate();
ASSERT(ebp_as_smi.is_valid());
__ mov(ebp_as_smi.reg(), Operand(ebp));
frame_->Push(&ebp_as_smi);
}
void CodeGenerator::GenerateRandomPositiveSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
frame_->SpillAll();
// Make sure the frame is aligned like the OS expects.
static const int kFrameAlignment = OS::ActivationFrameAlignment();
if (kFrameAlignment > 0) {
ASSERT(IsPowerOf2(kFrameAlignment));
__ mov(edi, Operand(esp)); // Save in callee-saved register.
__ and_(esp, -kFrameAlignment);
}
// Call V8::RandomPositiveSmi().
__ call(FUNCTION_ADDR(V8::RandomPositiveSmi), RelocInfo::RUNTIME_ENTRY);
// Restore stack pointer from callee-saved register edi.
if (kFrameAlignment > 0) {
__ mov(esp, Operand(edi));
}
Result result = allocator_->Allocate(eax);
frame_->Push(&result);
}
void CodeGenerator::GenerateStringAdd(ZoneList<Expression*>* args) {
ASSERT_EQ(2, args->length());
Load(args->at(0));
Load(args->at(1));
StringAddStub stub(NO_STRING_ADD_FLAGS);
Result answer = frame_->CallStub(&stub, 2);
frame_->Push(&answer);
}
void CodeGenerator::GenerateSubString(ZoneList<Expression*>* args) {
ASSERT_EQ(3, args->length());
Load(args->at(0));
Load(args->at(1));
Load(args->at(2));
SubStringStub stub;
Result answer = frame_->CallStub(&stub, 3);
frame_->Push(&answer);
}
void CodeGenerator::GenerateStringCompare(ZoneList<Expression*>* args) {
ASSERT_EQ(2, args->length());
Load(args->at(0));
Load(args->at(1));
StringCompareStub stub;
Result answer = frame_->CallStub(&stub, 2);
frame_->Push(&answer);
}
void CodeGenerator::GenerateRegExpExec(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 4);
// Load the arguments on the stack and call the stub.
Load(args->at(0));
Load(args->at(1));
Load(args->at(2));
Load(args->at(3));
RegExpExecStub stub;
Result result = frame_->CallStub(&stub, 4);
frame_->Push(&result);
}
void CodeGenerator::GenerateNumberToString(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
// Load the argument on the stack and call the stub.
Load(args->at(0));
NumberToStringStub stub;
Result result = frame_->CallStub(&stub, 1);
frame_->Push(&result);
}
void CodeGenerator::GenerateMathSin(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
Load(args->at(0));
TranscendentalCacheStub stub(TranscendentalCache::SIN);
Result result = frame_->CallStub(&stub, 1);
frame_->Push(&result);
}
void CodeGenerator::GenerateMathCos(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
Load(args->at(0));
TranscendentalCacheStub stub(TranscendentalCache::COS);
Result result = frame_->CallStub(&stub, 1);
frame_->Push(&result);
}
void CodeGenerator::VisitCallRuntime(CallRuntime* node) {
if (CheckForInlineRuntimeCall(node)) {
return;
}
ZoneList<Expression*>* args = node->arguments();
Comment cmnt(masm_, "[ CallRuntime");
Runtime::Function* function = node->function();
if (function == NULL) {
// Push the builtins object found in the current global object.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), GlobalObject());
__ mov(temp.reg(), FieldOperand(temp.reg(), GlobalObject::kBuiltinsOffset));
frame_->Push(&temp);
}
// Push the arguments ("left-to-right").
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
if (function == NULL) {
// Call the JS runtime function.
frame_->Push(node->name());
Result answer = frame_->CallCallIC(RelocInfo::CODE_TARGET,
arg_count,
loop_nesting_);
frame_->RestoreContextRegister();
frame_->Push(&answer);
} else {
// Call the C runtime function.
Result answer = frame_->CallRuntime(function, arg_count);
frame_->Push(&answer);
}
}
void CodeGenerator::VisitUnaryOperation(UnaryOperation* node) {
Comment cmnt(masm_, "[ UnaryOperation");
Token::Value op = node->op();
if (op == Token::NOT) {
// Swap the true and false targets but keep the same actual label
// as the fall through.
destination()->Invert();
LoadCondition(node->expression(), destination(), true);
// Swap the labels back.
destination()->Invert();
} else if (op == Token::DELETE) {
Property* property = node->expression()->AsProperty();
if (property != NULL) {
Load(property->obj());
Load(property->key());
Result answer = frame_->InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
}
Variable* variable = node->expression()->AsVariableProxy()->AsVariable();
if (variable != NULL) {
Slot* slot = variable->slot();
if (variable->is_global()) {
LoadGlobal();
frame_->Push(variable->name());
Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
} else if (slot != NULL && slot->type() == Slot::LOOKUP) {
// Call the runtime to look up the context holding the named
// variable. Sync the virtual frame eagerly so we can push the
// arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(variable->name()));
Result context = frame_->CallRuntime(Runtime::kLookupContext, 2);
ASSERT(context.is_register());
frame_->EmitPush(context.reg());
context.Unuse();
frame_->EmitPush(Immediate(variable->name()));
Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
}
// Default: Result of deleting non-global, not dynamically
// introduced variables is false.
frame_->Push(Factory::false_value());
} else {
// Default: Result of deleting expressions is true.
Load(node->expression()); // may have side-effects
frame_->SetElementAt(0, Factory::true_value());
}
} else if (op == Token::TYPEOF) {
// Special case for loading the typeof expression; see comment on
// LoadTypeofExpression().
LoadTypeofExpression(node->expression());
Result answer = frame_->CallRuntime(Runtime::kTypeof, 1);
frame_->Push(&answer);
} else if (op == Token::VOID) {
Expression* expression = node->expression();
if (expression && expression->AsLiteral() && (
expression->AsLiteral()->IsTrue() ||
expression->AsLiteral()->IsFalse() ||
expression->AsLiteral()->handle()->IsNumber() ||
expression->AsLiteral()->handle()->IsString() ||
expression->AsLiteral()->handle()->IsJSRegExp() ||
expression->AsLiteral()->IsNull())) {
// Omit evaluating the value of the primitive literal.
// It will be discarded anyway, and can have no side effect.
frame_->Push(Factory::undefined_value());
} else {
Load(node->expression());
frame_->SetElementAt(0, Factory::undefined_value());
}
} else {
Load(node->expression());
bool overwrite =
(node->expression()->AsBinaryOperation() != NULL &&
node->expression()->AsBinaryOperation()->ResultOverwriteAllowed());
switch (op) {
case Token::SUB: {
GenericUnaryOpStub stub(Token::SUB, overwrite);
Result operand = frame_->Pop();
Result answer = frame_->CallStub(&stub, &operand);
frame_->Push(&answer);
break;
}
case Token::BIT_NOT: {
// Smi check.
JumpTarget smi_label;
JumpTarget continue_label;
Result operand = frame_->Pop();
operand.ToRegister();
__ test(operand.reg(), Immediate(kSmiTagMask));
smi_label.Branch(zero, &operand, taken);
GenericUnaryOpStub stub(Token::BIT_NOT, overwrite);
Result answer = frame_->CallStub(&stub, &operand);
continue_label.Jump(&answer);
smi_label.Bind(&answer);
answer.ToRegister();
frame_->Spill(answer.reg());
__ not_(answer.reg());
__ and_(answer.reg(), ~kSmiTagMask); // Remove inverted smi-tag.
continue_label.Bind(&answer);
frame_->Push(&answer);
break;
}
case Token::ADD: {
// Smi check.
JumpTarget continue_label;
Result operand = frame_->Pop();
operand.ToRegister();
__ test(operand.reg(), Immediate(kSmiTagMask));
continue_label.Branch(zero, &operand, taken);
frame_->Push(&operand);
Result answer = frame_->InvokeBuiltin(Builtins::TO_NUMBER,
CALL_FUNCTION, 1);
continue_label.Bind(&answer);
frame_->Push(&answer);
break;
}
default:
// NOT, DELETE, TYPEOF, and VOID are handled outside the
// switch.
UNREACHABLE();
}
}
}
// The value in dst was optimistically incremented or decremented. The
// result overflowed or was not smi tagged. Undo the operation, call
// into the runtime to convert the argument to a number, and call the
// specialized add or subtract stub. The result is left in dst.
class DeferredPrefixCountOperation: public DeferredCode {
public:
DeferredPrefixCountOperation(Register dst, bool is_increment)
: dst_(dst), is_increment_(is_increment) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
bool is_increment_;
};
void DeferredPrefixCountOperation::Generate() {
// Undo the optimistic smi operation.
if (is_increment_) {
__ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
} else {
__ add(Operand(dst_), Immediate(Smi::FromInt(1)));
}
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
__ push(eax);
__ push(Immediate(Smi::FromInt(1)));
if (is_increment_) {
__ CallRuntime(Runtime::kNumberAdd, 2);
} else {
__ CallRuntime(Runtime::kNumberSub, 2);
}
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The value in dst was optimistically incremented or decremented. The
// result overflowed or was not smi tagged. Undo the operation and call
// into the runtime to convert the argument to a number. Update the
// original value in old. Call the specialized add or subtract stub.
// The result is left in dst.
class DeferredPostfixCountOperation: public DeferredCode {
public:
DeferredPostfixCountOperation(Register dst, Register old, bool is_increment)
: dst_(dst), old_(old), is_increment_(is_increment) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
Register old_;
bool is_increment_;
};
void DeferredPostfixCountOperation::Generate() {
// Undo the optimistic smi operation.
if (is_increment_) {
__ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
} else {
__ add(Operand(dst_), Immediate(Smi::FromInt(1)));
}
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
// Save the result of ToNumber to use as the old value.
__ push(eax);
// Call the runtime for the addition or subtraction.
__ push(eax);
__ push(Immediate(Smi::FromInt(1)));
if (is_increment_) {
__ CallRuntime(Runtime::kNumberAdd, 2);
} else {
__ CallRuntime(Runtime::kNumberSub, 2);
}
if (!dst_.is(eax)) __ mov(dst_, eax);
__ pop(old_);
}
void CodeGenerator::VisitCountOperation(CountOperation* node) {
Comment cmnt(masm_, "[ CountOperation");
bool is_postfix = node->is_postfix();
bool is_increment = node->op() == Token::INC;
Variable* var = node->expression()->AsVariableProxy()->AsVariable();
bool is_const = (var != NULL && var->mode() == Variable::CONST);
// Postfix operations need a stack slot under the reference to hold
// the old value while the new value is being stored. This is so that
// in the case that storing the new value requires a call, the old
// value will be in the frame to be spilled.
if (is_postfix) frame_->Push(Smi::FromInt(0));
// A constant reference is not saved to, so a constant reference is not a
// compound assignment reference.
{ Reference target(this, node->expression(), !is_const);
if (target.is_illegal()) {
// Spoof the virtual frame to have the expected height (one higher
// than on entry).
if (!is_postfix) frame_->Push(Smi::FromInt(0));
return;
}
target.TakeValue();
Result new_value = frame_->Pop();
new_value.ToRegister();
Result old_value; // Only allocated in the postfix case.
if (is_postfix) {
// Allocate a temporary to preserve the old value.
old_value = allocator_->Allocate();
ASSERT(old_value.is_valid());
__ mov(old_value.reg(), new_value.reg());
}
// Ensure the new value is writable.
frame_->Spill(new_value.reg());
// In order to combine the overflow and the smi tag check, we need
// to be able to allocate a byte register. We attempt to do so
// without spilling. If we fail, we will generate separate overflow
// and smi tag checks.
//
// We allocate and clear the temporary byte register before
// performing the count operation since clearing the register using
// xor will clear the overflow flag.
Result tmp = allocator_->AllocateByteRegisterWithoutSpilling();
if (tmp.is_valid()) {
__ Set(tmp.reg(), Immediate(0));
}
DeferredCode* deferred = NULL;
if (is_postfix) {
deferred = new DeferredPostfixCountOperation(new_value.reg(),
old_value.reg(),
is_increment);
} else {
deferred = new DeferredPrefixCountOperation(new_value.reg(),
is_increment);
}
if (is_increment) {
__ add(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
} else {
__ sub(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
}
// If the count operation didn't overflow and the result is a valid
// smi, we're done. Otherwise, we jump to the deferred slow-case
// code.
if (tmp.is_valid()) {
// We combine the overflow and the smi tag check if we could
// successfully allocate a temporary byte register.
__ setcc(overflow, tmp.reg());
__ or_(Operand(tmp.reg()), new_value.reg());
__ test(tmp.reg(), Immediate(kSmiTagMask));
tmp.Unuse();
deferred->Branch(not_zero);
} else {
// Otherwise we test separately for overflow and smi tag.
deferred->Branch(overflow);
__ test(new_value.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
}
deferred->BindExit();
// Postfix: store the old value in the allocated slot under the
// reference.
if (is_postfix) frame_->SetElementAt(target.size(), &old_value);
frame_->Push(&new_value);
// Non-constant: update the reference.
if (!is_const) target.SetValue(NOT_CONST_INIT);
}
// Postfix: drop the new value and use the old.
if (is_postfix) frame_->Drop();
}
void CodeGenerator::VisitBinaryOperation(BinaryOperation* node) {
Comment cmnt(masm_, "[ BinaryOperation");
Token::Value op = node->op();
// According to ECMA-262 section 11.11, page 58, the binary logical
// operators must yield the result of one of the two expressions
// before any ToBoolean() conversions. This means that the value
// produced by a && or || operator is not necessarily a boolean.
// NOTE: If the left hand side produces a materialized value (not
// control flow), we force the right hand side to do the same. This
// is necessary because we assume that if we get control flow on the
// last path out of an expression we got it on all paths.
if (op == Token::AND) {
JumpTarget is_true;
ControlDestination dest(&is_true, destination()->false_target(), true);
LoadCondition(node->left(), &dest, false);
if (dest.false_was_fall_through()) {
// The current false target was used as the fall-through. If
// there are no dangling jumps to is_true then the left
// subexpression was unconditionally false. Otherwise we have
// paths where we do have to evaluate the right subexpression.
if (is_true.is_linked()) {
// We need to compile the right subexpression. If the jump to
// the current false target was a forward jump then we have a
// valid frame, we have just bound the false target, and we
// have to jump around the code for the right subexpression.
if (has_valid_frame()) {
destination()->false_target()->Unuse();
destination()->false_target()->Jump();
}
is_true.Bind();
// The left subexpression compiled to control flow, so the
// right one is free to do so as well.
LoadCondition(node->right(), destination(), false);
} else {
// We have actually just jumped to or bound the current false
// target but the current control destination is not marked as
// used.
destination()->Use(false);
}
} else if (dest.is_used()) {
// The left subexpression compiled to control flow (and is_true
// was just bound), so the right is free to do so as well.
LoadCondition(node->right(), destination(), false);
} else {
// We have a materialized value on the frame, so we exit with
// one on all paths. There are possibly also jumps to is_true
// from nested subexpressions.
JumpTarget pop_and_continue;
JumpTarget exit;
// Avoid popping the result if it converts to 'false' using the
// standard ToBoolean() conversion as described in ECMA-262,
// section 9.2, page 30.
//
// Duplicate the TOS value. The duplicate will be popped by
// ToBoolean.
frame_->Dup();
ControlDestination dest(&pop_and_continue, &exit, true);
ToBoolean(&dest);
// Pop the result of evaluating the first part.
frame_->Drop();
// Compile right side expression.
is_true.Bind();
Load(node->right());
// Exit (always with a materialized value).
exit.Bind();
}
} else if (op == Token::OR) {
JumpTarget is_false;
ControlDestination dest(destination()->true_target(), &is_false, false);
LoadCondition(node->left(), &dest, false);
if (dest.true_was_fall_through()) {
// The current true target was used as the fall-through. If
// there are no dangling jumps to is_false then the left
// subexpression was unconditionally true. Otherwise we have
// paths where we do have to evaluate the right subexpression.
if (is_false.is_linked()) {
// We need to compile the right subexpression. If the jump to
// the current true target was a forward jump then we have a
// valid frame, we have just bound the true target, and we
// have to jump around the code for the right subexpression.
if (has_valid_frame()) {
destination()->true_target()->Unuse();
destination()->true_target()->Jump();
}
is_false.Bind();
// The left subexpression compiled to control flow, so the
// right one is free to do so as well.
LoadCondition(node->right(), destination(), false);
} else {
// We have just jumped to or bound the current true target but
// the current control destination is not marked as used.
destination()->Use(true);
}
} else if (dest.is_used()) {
// The left subexpression compiled to control flow (and is_false
// was just bound), so the right is free to do so as well.
LoadCondition(node->right(), destination(), false);
} else {
// We have a materialized value on the frame, so we exit with
// one on all paths. There are possibly also jumps to is_false
// from nested subexpressions.
JumpTarget pop_and_continue;
JumpTarget exit;
// Avoid popping the result if it converts to 'true' using the
// standard ToBoolean() conversion as described in ECMA-262,
// section 9.2, page 30.
//
// Duplicate the TOS value. The duplicate will be popped by
// ToBoolean.
frame_->Dup();
ControlDestination dest(&exit, &pop_and_continue, false);
ToBoolean(&dest);
// Pop the result of evaluating the first part.
frame_->Drop();
// Compile right side expression.
is_false.Bind();
Load(node->right());
// Exit (always with a materialized value).
exit.Bind();
}
} else {
// NOTE: The code below assumes that the slow cases (calls to runtime)
// never return a constant/immutable object.
OverwriteMode overwrite_mode = NO_OVERWRITE;
if (node->left()->AsBinaryOperation() != NULL &&
node->left()->AsBinaryOperation()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_LEFT;
} else if (node->right()->AsBinaryOperation() != NULL &&
node->right()->AsBinaryOperation()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_RIGHT;
}
Load(node->left());
Load(node->right());
GenericBinaryOperation(node->op(), node->type(), overwrite_mode);
}
}
void CodeGenerator::VisitThisFunction(ThisFunction* node) {
frame_->PushFunction();
}
void CodeGenerator::VisitCompareOperation(CompareOperation* node) {
Comment cmnt(masm_, "[ CompareOperation");
bool left_already_loaded = false;
// Get the expressions from the node.
Expression* left = node->left();
Expression* right = node->right();
Token::Value op = node->op();
// To make typeof testing for natives implemented in JavaScript really
// efficient, we generate special code for expressions of the form:
// 'typeof <expression> == <string>'.
UnaryOperation* operation = left->AsUnaryOperation();
if ((op == Token::EQ || op == Token::EQ_STRICT) &&
(operation != NULL && operation->op() == Token::TYPEOF) &&
(right->AsLiteral() != NULL &&
right->AsLiteral()->handle()->IsString())) {
Handle<String> check(String::cast(*right->AsLiteral()->handle()));
// Load the operand and move it to a register.
LoadTypeofExpression(operation->expression());
Result answer = frame_->Pop();
answer.ToRegister();
if (check->Equals(Heap::number_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->true_target()->Branch(zero);
frame_->Spill(answer.reg());
__ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ cmp(answer.reg(), Factory::heap_number_map());
answer.Unuse();
destination()->Split(equal);
} else if (check->Equals(Heap::string_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
// It can be an undetectable string object.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kBitFieldOffset));
__ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
destination()->false_target()->Branch(not_zero);
__ CmpObjectType(answer.reg(), FIRST_NONSTRING_TYPE, temp.reg());
temp.Unuse();
answer.Unuse();
destination()->Split(below);
} else if (check->Equals(Heap::boolean_symbol())) {
__ cmp(answer.reg(), Factory::true_value());
destination()->true_target()->Branch(equal);
__ cmp(answer.reg(), Factory::false_value());
answer.Unuse();
destination()->Split(equal);
} else if (check->Equals(Heap::undefined_symbol())) {
__ cmp(answer.reg(), Factory::undefined_value());
destination()->true_target()->Branch(equal);
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
// It can be an undetectable object.
frame_->Spill(answer.reg());
__ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(answer.reg(),
FieldOperand(answer.reg(), Map::kBitFieldOffset));
__ test(answer.reg(), Immediate(1 << Map::kIsUndetectable));
answer.Unuse();
destination()->Split(not_zero);
} else if (check->Equals(Heap::function_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
frame_->Spill(answer.reg());
__ CmpObjectType(answer.reg(), JS_FUNCTION_TYPE, answer.reg());
destination()->true_target()->Branch(equal);
// Regular expressions are callable so typeof == 'function'.
__ CmpInstanceType(answer.reg(), JS_REGEXP_TYPE);
answer.Unuse();
destination()->Split(equal);
} else if (check->Equals(Heap::object_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
__ cmp(answer.reg(), Factory::null_value());
destination()->true_target()->Branch(equal);
Result map = allocator()->Allocate();
ASSERT(map.is_valid());
// Regular expressions are typeof == 'function', not 'object'.
__ CmpObjectType(answer.reg(), JS_REGEXP_TYPE, map.reg());
destination()->false_target()->Branch(equal);
// It can be an undetectable object.
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kBitFieldOffset));
__ test(map.reg(), Immediate(1 << Map::kIsUndetectable));
destination()->false_target()->Branch(not_zero);
__ mov(map.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
__ cmp(map.reg(), FIRST_JS_OBJECT_TYPE);
destination()->false_target()->Branch(less);
__ cmp(map.reg(), LAST_JS_OBJECT_TYPE);
answer.Unuse();
map.Unuse();
destination()->Split(less_equal);
} else {
// Uncommon case: typeof testing against a string literal that is
// never returned from the typeof operator.
answer.Unuse();
destination()->Goto(false);
}
return;
} else if (op == Token::LT &&
right->AsLiteral() != NULL &&
right->AsLiteral()->handle()->IsHeapNumber()) {
Handle<HeapNumber> check(HeapNumber::cast(*right->AsLiteral()->handle()));
if (check->value() == 2147483648.0) { // 0x80000000.
Load(left);
left_already_loaded = true;
Result lhs = frame_->Pop();
lhs.ToRegister();
__ test(lhs.reg(), Immediate(kSmiTagMask));
destination()->true_target()->Branch(zero); // All Smis are less.
Result scratch = allocator()->Allocate();
ASSERT(scratch.is_valid());
__ mov(scratch.reg(), FieldOperand(lhs.reg(), HeapObject::kMapOffset));
__ cmp(scratch.reg(), Factory::heap_number_map());
JumpTarget not_a_number;
not_a_number.Branch(not_equal, &lhs);
__ mov(scratch.reg(),
FieldOperand(lhs.reg(), HeapNumber::kExponentOffset));
__ cmp(Operand(scratch.reg()), Immediate(0xfff00000));
not_a_number.Branch(above_equal, &lhs); // It's a negative NaN or -Inf.
const uint32_t borderline_exponent =
(HeapNumber::kExponentBias + 31) << HeapNumber::kExponentShift;
__ cmp(Operand(scratch.reg()), Immediate(borderline_exponent));
scratch.Unuse();
lhs.Unuse();
destination()->true_target()->Branch(less);
destination()->false_target()->Jump();
not_a_number.Bind(&lhs);
frame_->Push(&lhs);
}
}
Condition cc = no_condition;
bool strict = false;
switch (op) {
case Token::EQ_STRICT:
strict = true;
// Fall through
case Token::EQ:
cc = equal;
break;
case Token::LT:
cc = less;
break;
case Token::GT:
cc = greater;
break;
case Token::LTE:
cc = less_equal;
break;
case Token::GTE:
cc = greater_equal;
break;
case Token::IN: {
if (!left_already_loaded) Load(left);
Load(right);
Result answer = frame_->InvokeBuiltin(Builtins::IN, CALL_FUNCTION, 2);
frame_->Push(&answer); // push the result
return;
}
case Token::INSTANCEOF: {
if (!left_already_loaded) Load(left);
Load(right);
InstanceofStub stub;
Result answer = frame_->CallStub(&stub, 2);
answer.ToRegister();
__ test(answer.reg(), Operand(answer.reg()));
answer.Unuse();
destination()->Split(zero);
return;
}
default:
UNREACHABLE();
}
if (!left_already_loaded) Load(left);
Load(right);
Comparison(node, cc, strict, destination());
}
#ifdef DEBUG
bool CodeGenerator::HasValidEntryRegisters() {
return (allocator()->count(eax) == (frame()->is_used(eax) ? 1 : 0))
&& (allocator()->count(ebx) == (frame()->is_used(ebx) ? 1 : 0))
&& (allocator()->count(ecx) == (frame()->is_used(ecx) ? 1 : 0))
&& (allocator()->count(edx) == (frame()->is_used(edx) ? 1 : 0))
&& (allocator()->count(edi) == (frame()->is_used(edi) ? 1 : 0));
}
#endif
// Emit a LoadIC call to get the value from receiver and leave it in
// dst.
class DeferredReferenceGetNamedValue: public DeferredCode {
public:
DeferredReferenceGetNamedValue(Register dst,
Register receiver,
Handle<String> name)
: dst_(dst), receiver_(receiver), name_(name) {
set_comment("[ DeferredReferenceGetNamedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Label patch_site_;
Register dst_;
Register receiver_;
Handle<String> name_;
};
void DeferredReferenceGetNamedValue::Generate() {
if (!receiver_.is(eax)) {
__ mov(eax, receiver_);
}
__ Set(ecx, Immediate(name_));
Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
__ call(ic, RelocInfo::CODE_TARGET);
// The call must be followed by a test eax instruction to indicate
// that the inobject property case was inlined.
//
// Store the delta to the map check instruction here in the test
// instruction. Use masm_-> instead of the __ macro since the
// latter can't return a value.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
// Here we use masm_-> instead of the __ macro because this is the
// instruction that gets patched and coverage code gets in the way.
masm_->test(eax, Immediate(-delta_to_patch_site));
__ IncrementCounter(&Counters::named_load_inline_miss, 1);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
class DeferredReferenceGetKeyedValue: public DeferredCode {
public:
explicit DeferredReferenceGetKeyedValue(Register dst,
Register receiver,
Register key)
: dst_(dst), receiver_(receiver), key_(key) {
set_comment("[ DeferredReferenceGetKeyedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Label patch_site_;
Register dst_;
Register receiver_;
Register key_;
};
void DeferredReferenceGetKeyedValue::Generate() {
if (!receiver_.is(eax)) {
// Register eax is available for key.
if (!key_.is(eax)) {
__ mov(eax, key_);
}
if (!receiver_.is(edx)) {
__ mov(edx, receiver_);
}
} else if (!key_.is(edx)) {
// Register edx is available for receiver.
if (!receiver_.is(edx)) {
__ mov(edx, receiver_);
}
if (!key_.is(eax)) {
__ mov(eax, key_);
}
} else {
__ xchg(edx, eax);
}
// Calculate the delta from the IC call instruction to the map check
// cmp instruction in the inlined version. This delta is stored in
// a test(eax, delta) instruction after the call so that we can find
// it in the IC initialization code and patch the cmp instruction.
// This means that we cannot allow test instructions after calls to
// KeyedLoadIC stubs in other places.
Handle<Code> ic(Builtins::builtin(Builtins::KeyedLoadIC_Initialize));
__ call(ic, RelocInfo::CODE_TARGET);
// The delta from the start of the map-compare instruction to the
// test instruction. We use masm_-> directly here instead of the __
// macro because the macro sometimes uses macro expansion to turn
// into something that can't return a value. This is encountered
// when doing generated code coverage tests.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
// Here we use masm_-> instead of the __ macro because this is the
// instruction that gets patched and coverage code gets in the way.
masm_->test(eax, Immediate(-delta_to_patch_site));
__ IncrementCounter(&Counters::keyed_load_inline_miss, 1);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
class DeferredReferenceSetKeyedValue: public DeferredCode {
public:
DeferredReferenceSetKeyedValue(Register value,
Register key,
Register receiver)
: value_(value), key_(key), receiver_(receiver) {
set_comment("[ DeferredReferenceSetKeyedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Register value_;
Register key_;
Register receiver_;
Label patch_site_;
};
void DeferredReferenceSetKeyedValue::Generate() {
__ IncrementCounter(&Counters::keyed_store_inline_miss, 1);
// Push receiver and key arguments on the stack.
__ push(receiver_);
__ push(key_);
// Move value argument to eax as expected by the IC stub.
if (!value_.is(eax)) __ mov(eax, value_);
// Call the IC stub.
Handle<Code> ic(Builtins::builtin(Builtins::KeyedStoreIC_Initialize));
__ call(ic, RelocInfo::CODE_TARGET);
// The delta from the start of the map-compare instruction to the
// test instruction. We use masm_-> directly here instead of the
// __ macro because the macro sometimes uses macro expansion to turn
// into something that can't return a value. This is encountered
// when doing generated code coverage tests.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
// Here we use masm_-> instead of the __ macro because this is the
// instruction that gets patched and coverage code gets in the way.
masm_->test(eax, Immediate(-delta_to_patch_site));
// Restore value (returned from store IC), key and receiver
// registers.
if (!value_.is(eax)) __ mov(value_, eax);
__ pop(key_);
__ pop(receiver_);
}
Result CodeGenerator::EmitNamedLoad(Handle<String> name, bool is_contextual) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Result result;
// Do not inline the inobject property case for loads from the global
// object. Also do not inline for unoptimized code. This saves time in
// the code generator. Unoptimized code is toplevel code or code that is
// not in a loop.
if (is_contextual || scope()->is_global_scope() || loop_nesting() == 0) {
Comment cmnt(masm(), "[ Load from named Property");
frame()->Push(name);
RelocInfo::Mode mode = is_contextual
? RelocInfo::CODE_TARGET_CONTEXT
: RelocInfo::CODE_TARGET;
result = frame()->CallLoadIC(mode);
// A test eax instruction following the call signals that the inobject
// property case was inlined. Ensure that there is not a test eax
// instruction here.
__ nop();
} else {
// Inline the inobject property case.
Comment cmnt(masm(), "[ Inlined named property load");
Result receiver = frame()->Pop();
receiver.ToRegister();
result = allocator()->Allocate();
ASSERT(result.is_valid());
DeferredReferenceGetNamedValue* deferred =
new DeferredReferenceGetNamedValue(result.reg(), receiver.reg(), name);
// Check that the receiver is a heap object.
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
__ bind(deferred->patch_site());
// This is the map check instruction that will be patched (so we can't
// use the double underscore macro that may insert instructions).
// Initially use an invalid map to force a failure.
masm()->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
Immediate(Factory::null_value()));
// This branch is always a forwards branch so it's always a fixed size
// which allows the assert below to succeed and patching to work.
deferred->Branch(not_equal);
// The delta from the patch label to the load offset must be statically
// known.
ASSERT(masm()->SizeOfCodeGeneratedSince(deferred->patch_site()) ==
LoadIC::kOffsetToLoadInstruction);
// The initial (invalid) offset has to be large enough to force a 32-bit
// instruction encoding to allow patching with an arbitrary offset. Use
// kMaxInt (minus kHeapObjectTag).
int offset = kMaxInt;
masm()->mov(result.reg(), FieldOperand(receiver.reg(), offset));
__ IncrementCounter(&Counters::named_load_inline, 1);
deferred->BindExit();
}
ASSERT(frame()->height() == original_height - 1);
return result;
}
Result CodeGenerator::EmitNamedStore(Handle<String> name, bool is_contextual) {
#ifdef DEBUG
int expected_height = frame()->height() - (is_contextual ? 1 : 2);
#endif
Result result = frame()->CallStoreIC(name, is_contextual);
ASSERT_EQ(expected_height, frame()->height());
return result;
}
Result CodeGenerator::EmitKeyedLoad() {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Result result;
// Inline array load code if inside of a loop. We do not know the
// receiver map yet, so we initially generate the code with a check
// against an invalid map. In the inline cache code, we patch the map
// check if appropriate.
if (loop_nesting() > 0) {
Comment cmnt(masm_, "[ Inlined load from keyed Property");
Result key = frame_->Pop();
Result receiver = frame_->Pop();
key.ToRegister();
receiver.ToRegister();
// Use a fresh temporary to load the elements without destroying
// the receiver which is needed for the deferred slow case.
Result elements = allocator()->Allocate();
ASSERT(elements.is_valid());
// Use a fresh temporary for the index and later the loaded
// value.
result = allocator()->Allocate();
ASSERT(result.is_valid());
DeferredReferenceGetKeyedValue* deferred =
new DeferredReferenceGetKeyedValue(result.reg(),
receiver.reg(),
key.reg());
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
// Initially, use an invalid map. The map is patched in the IC
// initialization code.
__ bind(deferred->patch_site());
// Use masm-> here instead of the double underscore macro since extra
// coverage code can interfere with the patching.
masm_->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
Immediate(Factory::null_value()));
deferred->Branch(not_equal);
// Check that the key is a smi.
__ test(key.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
// Get the elements array from the receiver and check that it
// is not a dictionary.
__ mov(elements.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
__ cmp(FieldOperand(elements.reg(), HeapObject::kMapOffset),
Immediate(Factory::fixed_array_map()));
deferred->Branch(not_equal);
// Shift the key to get the actual index value and check that
// it is within bounds.
__ mov(result.reg(), key.reg());
__ SmiUntag(result.reg());
__ cmp(result.reg(),
FieldOperand(elements.reg(), FixedArray::kLengthOffset));
deferred->Branch(above_equal);
// Load and check that the result is not the hole.
__ mov(result.reg(), Operand(elements.reg(),
result.reg(),
times_4,
FixedArray::kHeaderSize - kHeapObjectTag));
elements.Unuse();
__ cmp(Operand(result.reg()), Immediate(Factory::the_hole_value()));
deferred->Branch(equal);
__ IncrementCounter(&Counters::keyed_load_inline, 1);
deferred->BindExit();
} else {
Comment cmnt(masm_, "[ Load from keyed Property");
result = frame_->CallKeyedLoadIC(RelocInfo::CODE_TARGET);
// Make sure that we do not have a test instruction after the
// call. A test instruction after the call is used to
// indicate that we have generated an inline version of the
// keyed load. The explicit nop instruction is here because
// the push that follows might be peep-hole optimized away.
__ nop();
}
ASSERT(frame()->height() == original_height - 2);
return result;
}
Result CodeGenerator::EmitKeyedStore(StaticType* key_type) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Result result;
// Generate inlined version of the keyed store if the code is in a loop
// and the key is likely to be a smi.
if (loop_nesting() > 0 && key_type->IsLikelySmi()) {
Comment cmnt(masm(), "[ Inlined store to keyed Property");
// Get the receiver, key and value into registers.
result = frame()->Pop();
Result key = frame()->Pop();
Result receiver = frame()->Pop();
Result tmp = allocator_->Allocate();
ASSERT(tmp.is_valid());
// Determine whether the value is a constant before putting it in a
// register.
bool value_is_constant = result.is_constant();
// Make sure that value, key and receiver are in registers.
result.ToRegister();
key.ToRegister();
receiver.ToRegister();
DeferredReferenceSetKeyedValue* deferred =
new DeferredReferenceSetKeyedValue(result.reg(),
key.reg(),
receiver.reg());
// Check that the value is a smi if it is not a constant. We can skip
// the write barrier for smis and constants.
if (!value_is_constant) {
__ test(result.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
}
// Check that the key is a non-negative smi.
__ test(key.reg(), Immediate(kSmiTagMask | 0x80000000));
deferred->Branch(not_zero);
// Check that the receiver is not a smi.
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
// Check that the receiver is a JSArray.
__ mov(tmp.reg(),
FieldOperand(receiver.reg(), HeapObject::kMapOffset));
__ movzx_b(tmp.reg(),
FieldOperand(tmp.reg(), Map::kInstanceTypeOffset));
__ cmp(tmp.reg(), JS_ARRAY_TYPE);
deferred->Branch(not_equal);
// Check that the key is within bounds. Both the key and the length of
// the JSArray are smis.
__ cmp(key.reg(),
FieldOperand(receiver.reg(), JSArray::kLengthOffset));
deferred->Branch(greater_equal);
// Get the elements array from the receiver and check that it is not a
// dictionary.
__ mov(tmp.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
// Bind the deferred code patch site to be able to locate the fixed
// array map comparison. When debugging, we patch this comparison to
// always fail so that we will hit the IC call in the deferred code
// which will allow the debugger to break for fast case stores.
__ bind(deferred->patch_site());
__ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
Immediate(Factory::fixed_array_map()));
deferred->Branch(not_equal);
// Store the value.
__ mov(Operand(tmp.reg(),
key.reg(),
times_2,
FixedArray::kHeaderSize - kHeapObjectTag),
result.reg());
__ IncrementCounter(&Counters::keyed_store_inline, 1);
deferred->BindExit();
} else {
result = frame()->CallKeyedStoreIC();
// Make sure that we do not have a test instruction after the
// call. A test instruction after the call is used to
// indicate that we have generated an inline version of the
// keyed store.
__ nop();
frame()->Drop(2);
}
ASSERT(frame()->height() == original_height - 3);
return result;
}
#undef __
#define __ ACCESS_MASM(masm)
Handle<String> Reference::GetName() {
ASSERT(type_ == NAMED);
Property* property = expression_->AsProperty();
if (property == NULL) {
// Global variable reference treated as a named property reference.
VariableProxy* proxy = expression_->AsVariableProxy();
ASSERT(proxy->AsVariable() != NULL);
ASSERT(proxy->AsVariable()->is_global());
return proxy->name();
} else {
Literal* raw_name = property->key()->AsLiteral();
ASSERT(raw_name != NULL);
return Handle<String>::cast(raw_name->handle());
}
}
void Reference::GetValue() {
ASSERT(!cgen_->in_spilled_code());
ASSERT(cgen_->HasValidEntryRegisters());
ASSERT(!is_illegal());
MacroAssembler* masm = cgen_->masm();
// Record the source position for the property load.
Property* property = expression_->AsProperty();
if (property != NULL) {
cgen_->CodeForSourcePosition(property->position());
}
switch (type_) {
case SLOT: {
Comment cmnt(masm, "[ Load from Slot");
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
Result result =
cgen_->LoadFromSlotCheckForArguments(slot, NOT_INSIDE_TYPEOF);
if (!persist_after_get_) set_unloaded();
cgen_->frame()->Push(&result);
break;
}
case NAMED: {
Variable* var = expression_->AsVariableProxy()->AsVariable();
bool is_global = var != NULL;
ASSERT(!is_global || var->is_global());
if (persist_after_get_) cgen_->frame()->Dup();
Result result = cgen_->EmitNamedLoad(GetName(), is_global);
if (!persist_after_get_) set_unloaded();
cgen_->frame()->Push(&result);
break;
}
case KEYED: {
if (persist_after_get_) {
cgen_->frame()->PushElementAt(1);
cgen_->frame()->PushElementAt(1);
}
Result value = cgen_->EmitKeyedLoad();
cgen_->frame()->Push(&value);
if (!persist_after_get_) set_unloaded();
break;
}
default:
UNREACHABLE();
}
}
void Reference::TakeValue() {
// For non-constant frame-allocated slots, we invalidate the value in the
// slot. For all others, we fall back on GetValue.
ASSERT(!cgen_->in_spilled_code());
ASSERT(!is_illegal());
if (type_ != SLOT) {
GetValue();
return;
}
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
if (slot->type() == Slot::LOOKUP ||
slot->type() == Slot::CONTEXT ||
slot->var()->mode() == Variable::CONST ||
slot->is_arguments()) {
GetValue();
return;
}
// Only non-constant, frame-allocated parameters and locals can
// reach here. Be careful not to use the optimizations for arguments
// object access since it may not have been initialized yet.
ASSERT(!slot->is_arguments());
if (slot->type() == Slot::PARAMETER) {
cgen_->frame()->TakeParameterAt(slot->index());
} else {
ASSERT(slot->type() == Slot::LOCAL);
cgen_->frame()->TakeLocalAt(slot->index());
}
ASSERT(persist_after_get_);
// Do not unload the reference, because it is used in SetValue.
}
void Reference::SetValue(InitState init_state) {
ASSERT(cgen_->HasValidEntryRegisters());
ASSERT(!is_illegal());
MacroAssembler* masm = cgen_->masm();
switch (type_) {
case SLOT: {
Comment cmnt(masm, "[ Store to Slot");
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
cgen_->StoreToSlot(slot, init_state);
set_unloaded();
break;
}
case NAMED: {
Comment cmnt(masm, "[ Store to named Property");
Result answer = cgen_->EmitNamedStore(GetName(), false);
cgen_->frame()->Push(&answer);
set_unloaded();
break;
}
case KEYED: {
Comment cmnt(masm, "[ Store to keyed Property");
Property* property = expression()->AsProperty();
ASSERT(property != NULL);
Result answer = cgen_->EmitKeyedStore(property->key()->type());
cgen_->frame()->Push(&answer);
set_unloaded();
break;
}
case UNLOADED:
case ILLEGAL:
UNREACHABLE();
}
}
void FastNewClosureStub::Generate(MacroAssembler* masm) {
// Clone the boilerplate in new space. Set the context to the
// current context in esi.
Label gc;
__ AllocateInNewSpace(JSFunction::kSize, eax, ebx, ecx, &gc, TAG_OBJECT);
// Get the boilerplate function from the stack.
__ mov(edx, Operand(esp, 1 * kPointerSize));
// Compute the function map in the current global context and set that
// as the map of the allocated object.
__ mov(ecx, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ mov(ecx, FieldOperand(ecx, GlobalObject::kGlobalContextOffset));
__ mov(ecx, Operand(ecx, Context::SlotOffset(Context::FUNCTION_MAP_INDEX)));
__ mov(FieldOperand(eax, JSObject::kMapOffset), ecx);
// Clone the rest of the boilerplate fields. We don't have to update
// the write barrier because the allocated object is in new space.
for (int offset = kPointerSize;
offset < JSFunction::kSize;
offset += kPointerSize) {
if (offset == JSFunction::kContextOffset) {
__ mov(FieldOperand(eax, offset), esi);
} else {
__ mov(ebx, FieldOperand(edx, offset));
__ mov(FieldOperand(eax, offset), ebx);
}
}
// Return and remove the on-stack parameter.
__ ret(1 * kPointerSize);
// Create a new closure through the slower runtime call.
__ bind(&gc);
__ pop(ecx); // Temporarily remove return address.
__ pop(edx);
__ push(esi);
__ push(edx);
__ push(ecx); // Restore return address.
__ TailCallRuntime(ExternalReference(Runtime::kNewClosure), 2, 1);
}
void FastNewContextStub::Generate(MacroAssembler* masm) {
// Try to allocate the context in new space.
Label gc;
int length = slots_ + Context::MIN_CONTEXT_SLOTS;
__ AllocateInNewSpace((length * kPointerSize) + FixedArray::kHeaderSize,
eax, ebx, ecx, &gc, TAG_OBJECT);
// Get the function from the stack.
__ mov(ecx, Operand(esp, 1 * kPointerSize));
// Setup the object header.
__ mov(FieldOperand(eax, HeapObject::kMapOffset), Factory::context_map());
__ mov(FieldOperand(eax, Array::kLengthOffset), Immediate(length));
// Setup the fixed slots.
__ xor_(ebx, Operand(ebx)); // Set to NULL.
__ mov(Operand(eax, Context::SlotOffset(Context::CLOSURE_INDEX)), ecx);
__ mov(Operand(eax, Context::SlotOffset(Context::FCONTEXT_INDEX)), eax);
__ mov(Operand(eax, Context::SlotOffset(Context::PREVIOUS_INDEX)), ebx);
__ mov(Operand(eax, Context::SlotOffset(Context::EXTENSION_INDEX)), ebx);
// Copy the global object from the surrounding context. We go through the
// context in the function (ecx) to match the allocation behavior we have
// in the runtime system (see Heap::AllocateFunctionContext).
__ mov(ebx, FieldOperand(ecx, JSFunction::kContextOffset));
__ mov(ebx, Operand(ebx, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ mov(Operand(eax, Context::SlotOffset(Context::GLOBAL_INDEX)), ebx);
// Initialize the rest of the slots to undefined.
__ mov(ebx, Factory::undefined_value());
for (int i = Context::MIN_CONTEXT_SLOTS; i < length; i++) {
__ mov(Operand(eax, Context::SlotOffset(i)), ebx);
}
// Return and remove the on-stack parameter.
__ mov(esi, Operand(eax));
__ ret(1 * kPointerSize);
// Need to collect. Call into runtime system.
__ bind(&gc);
__ TailCallRuntime(ExternalReference(Runtime::kNewContext), 1, 1);
}
void FastCloneShallowArrayStub::Generate(MacroAssembler* masm) {
// Stack layout on entry:
//
// [esp + kPointerSize]: constant elements.
// [esp + (2 * kPointerSize)]: literal index.
// [esp + (3 * kPointerSize)]: literals array.
// All sizes here are multiples of kPointerSize.
int elements_size = (length_ > 0) ? FixedArray::SizeFor(length_) : 0;
int size = JSArray::kSize + elements_size;
// Load boilerplate object into ecx and check if we need to create a
// boilerplate.
Label slow_case;
__ mov(ecx, Operand(esp, 3 * kPointerSize));
__ mov(eax, Operand(esp, 2 * kPointerSize));
ASSERT((kPointerSize == 4) && (kSmiTagSize == 1) && (kSmiTag == 0));
__ mov(ecx, FieldOperand(ecx, eax, times_2, FixedArray::kHeaderSize));
__ cmp(ecx, Factory::undefined_value());
__ j(equal, &slow_case);
// Allocate both the JS array and the elements array in one big
// allocation. This avoids multiple limit checks.
__ AllocateInNewSpace(size, eax, ebx, edx, &slow_case, TAG_OBJECT);
// Copy the JS array part.
for (int i = 0; i < JSArray::kSize; i += kPointerSize) {
if ((i != JSArray::kElementsOffset) || (length_ == 0)) {
__ mov(ebx, FieldOperand(ecx, i));
__ mov(FieldOperand(eax, i), ebx);
}
}
if (length_ > 0) {
// Get hold of the elements array of the boilerplate and setup the
// elements pointer in the resulting object.
__ mov(ecx, FieldOperand(ecx, JSArray::kElementsOffset));
__ lea(edx, Operand(eax, JSArray::kSize));
__ mov(FieldOperand(eax, JSArray::kElementsOffset), edx);
// Copy the elements array.
for (int i = 0; i < elements_size; i += kPointerSize) {
__ mov(ebx, FieldOperand(ecx, i));
__ mov(FieldOperand(edx, i), ebx);
}
}
// Return and remove the on-stack parameters.
__ ret(3 * kPointerSize);
__ bind(&slow_case);
ExternalReference runtime(Runtime::kCreateArrayLiteralShallow);
__ TailCallRuntime(runtime, 3, 1);
}
// NOTE: The stub does not handle the inlined cases (Smis, Booleans, undefined).
void ToBooleanStub::Generate(MacroAssembler* masm) {
Label false_result, true_result, not_string;
__ mov(eax, Operand(esp, 1 * kPointerSize));
// 'null' => false.
__ cmp(eax, Factory::null_value());
__ j(equal, &false_result);
// Get the map and type of the heap object.
__ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(edx, Map::kInstanceTypeOffset));
// Undetectable => false.
__ movzx_b(ebx, FieldOperand(edx, Map::kBitFieldOffset));
__ and_(ebx, 1 << Map::kIsUndetectable);
__ j(not_zero, &false_result);
// JavaScript object => true.
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(above_equal, &true_result);
// String value => false iff empty.
__ cmp(ecx, FIRST_NONSTRING_TYPE);
__ j(above_equal, ¬_string);
__ mov(edx, FieldOperand(eax, String::kLengthOffset));
__ test(edx, Operand(edx));
__ j(zero, &false_result);
__ jmp(&true_result);
__ bind(¬_string);
// HeapNumber => false iff +0, -0, or NaN.
__ cmp(edx, Factory::heap_number_map());
__ j(not_equal, &true_result);
__ fldz();
__ fld_d(FieldOperand(eax, HeapNumber::kValueOffset));
__ FCmp();
__ j(zero, &false_result);
// Fall through to |true_result|.
// Return 1/0 for true/false in eax.
__ bind(&true_result);
__ mov(eax, 1);
__ ret(1 * kPointerSize);
__ bind(&false_result);
__ mov(eax, 0);
__ ret(1 * kPointerSize);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Register left,
Register right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(left);
__ push(right);
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (!(left.is(left_arg) && right.is(right_arg))) {
if (left.is(right_arg) && right.is(left_arg)) {
if (IsOperationCommutative()) {
SetArgsReversed();
} else {
__ xchg(left, right);
}
} else if (left.is(left_arg)) {
__ mov(right_arg, right);
} else if (right.is(right_arg)) {
__ mov(left_arg, left);
} else if (left.is(right_arg)) {
if (IsOperationCommutative()) {
__ mov(left_arg, right);
SetArgsReversed();
} else {
// Order of moves important to avoid destroying left argument.
__ mov(left_arg, left);
__ mov(right_arg, right);
}
} else if (right.is(left_arg)) {
if (IsOperationCommutative()) {
__ mov(right_arg, left);
SetArgsReversed();
} else {
// Order of moves important to avoid destroying right argument.
__ mov(right_arg, right);
__ mov(left_arg, left);
}
} else {
// Order of moves is not important.
__ mov(left_arg, left);
__ mov(right_arg, right);
}
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Register left,
Smi* right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(left);
__ push(Immediate(right));
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (left.is(left_arg)) {
__ mov(right_arg, Immediate(right));
} else if (left.is(right_arg) && IsOperationCommutative()) {
__ mov(left_arg, Immediate(right));
SetArgsReversed();
} else {
// For non-commutative operations, left and right_arg might be
// the same register. Therefore, the order of the moves is
// important here in order to not overwrite left before moving
// it to left_arg.
__ mov(left_arg, left);
__ mov(right_arg, Immediate(right));
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Smi* left,
Register right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(Immediate(left));
__ push(right);
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (right.is(right_arg)) {
__ mov(left_arg, Immediate(left));
} else if (right.is(left_arg) && IsOperationCommutative()) {
__ mov(right_arg, Immediate(left));
SetArgsReversed();
} else {
// For non-commutative operations, right and left_arg might be
// the same register. Therefore, the order of the moves is
// important here in order to not overwrite right before moving
// it to right_arg.
__ mov(right_arg, right);
__ mov(left_arg, Immediate(left));
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
Result GenericBinaryOpStub::GenerateCall(MacroAssembler* masm,
VirtualFrame* frame,
Result* left,
Result* right) {
if (ArgsInRegistersSupported()) {
SetArgsInRegisters();
return frame->CallStub(this, left, right);
} else {
frame->Push(left);
frame->Push(right);
return frame->CallStub(this, 2);
}
}
void GenericBinaryOpStub::GenerateSmiCode(MacroAssembler* masm, Label* slow) {
// 1. Move arguments into edx, eax except for DIV and MOD, which need the
// dividend in eax and edx free for the division. Use eax, ebx for those.
Comment load_comment(masm, "-- Load arguments");
Register left = edx;
Register right = eax;
if (op_ == Token::DIV || op_ == Token::MOD) {
left = eax;
right = ebx;
if (HasArgsInRegisters()) {
__ mov(ebx, eax);
__ mov(eax, edx);
}
}
if (!HasArgsInRegisters()) {
__ mov(right, Operand(esp, 1 * kPointerSize));
__ mov(left, Operand(esp, 2 * kPointerSize));
}
// 2. Prepare the smi check of both operands by oring them together.
Comment smi_check_comment(masm, "-- Smi check arguments");
Label not_smis;
Register combined = ecx;
ASSERT(!left.is(combined) && !right.is(combined));
switch (op_) {
case Token::BIT_OR:
// Perform the operation into eax and smi check the result. Preserve
// eax in case the result is not a smi.
ASSERT(!left.is(ecx) && !right.is(ecx));
__ mov(ecx, right);
__ or_(right, Operand(left)); // Bitwise or is commutative.
combined = right;
break;
case Token::BIT_XOR:
case Token::BIT_AND:
case Token::ADD:
case Token::SUB:
case Token::MUL:
case Token::DIV:
case Token::MOD:
__ mov(combined, right);
__ or_(combined, Operand(left));
break;
case Token::SHL:
case Token::SAR:
case Token::SHR:
// Move the right operand into ecx for the shift operation, use eax
// for the smi check register.
ASSERT(!left.is(ecx) && !right.is(ecx));
__ mov(ecx, right);
__ or_(right, Operand(left));
combined = right;
break;
default:
break;
}
// 3. Perform the smi check of the operands.
ASSERT(kSmiTag == 0); // Adjust zero check if not the case.
__ test(combined, Immediate(kSmiTagMask));
__ j(not_zero, ¬_smis, not_taken);
// 4. Operands are both smis, perform the operation leaving the result in
// eax and check the result if necessary.
Comment perform_smi(masm, "-- Perform smi operation");
Label use_fp_on_smis;
switch (op_) {
case Token::BIT_OR:
// Nothing to do.
break;
case Token::BIT_XOR:
ASSERT(right.is(eax));
__ xor_(right, Operand(left)); // Bitwise xor is commutative.
break;
case Token::BIT_AND:
ASSERT(right.is(eax));
__ and_(right, Operand(left)); // Bitwise and is commutative.
break;
case Token::SHL:
// Remove tags from operands (but keep sign).
__ SmiUntag(left);
__ SmiUntag(ecx);
// Perform the operation.
__ shl_cl(left);
// Check that the *signed* result fits in a smi.
__ cmp(left, 0xc0000000);
__ j(sign, &use_fp_on_smis, not_taken);
// Tag the result and store it in register eax.
__ SmiTag(left);
__ mov(eax, left);
break;
case Token::SAR:
// Remove tags from operands (but keep sign).
__ SmiUntag(left);
__ SmiUntag(ecx);
// Perform the operation.
__ sar_cl(left);
// Tag the result and store it in register eax.
__ SmiTag(left);
__ mov(eax, left);
break;
case Token::SHR:
// Remove tags from operands (but keep sign).
__ SmiUntag(left);
__ SmiUntag(ecx);
// Perform the operation.
__ shr_cl(left);
// Check that the *unsigned* result fits in a smi.
// Neither of the two high-order bits can be set:
// - 0x80000000: high bit would be lost when smi tagging.
// - 0x40000000: this number would convert to negative when
// Smi tagging these two cases can only happen with shifts
// by 0 or 1 when handed a valid smi.
__ test(left, Immediate(0xc0000000));
__ j(not_zero, slow, not_taken);
// Tag the result and store it in register eax.
__ SmiTag(left);
__ mov(eax, left);
break;
case Token::ADD:
ASSERT(right.is(eax));
__ add(right, Operand(left)); // Addition is commutative.
__ j(overflow, &use_fp_on_smis, not_taken);
break;
case Token::SUB:
__ sub(left, Operand(right));
__ j(overflow, &use_fp_on_smis, not_taken);
__ mov(eax, left);
break;
case Token::MUL:
// If the smi tag is 0 we can just leave the tag on one operand.
ASSERT(kSmiTag == 0); // Adjust code below if not the case.
// We can't revert the multiplication if the result is not a smi
// so save the right operand.
__ mov(ebx, right);
// Remove tag from one of the operands (but keep sign).
__ SmiUntag(right);
// Do multiplication.
__ imul(right, Operand(left)); // Multiplication is commutative.
__ j(overflow, &use_fp_on_smis, not_taken);
// Check for negative zero result. Use combined = left | right.
__ NegativeZeroTest(right, combined, &use_fp_on_smis);
break;
case Token::DIV:
// We can't revert the division if the result is not a smi so
// save the left operand.
__ mov(edi, left);
// Check for 0 divisor.
__ test(right, Operand(right));
__ j(zero, &use_fp_on_smis, not_taken);
// Sign extend left into edx:eax.
ASSERT(left.is(eax));
__ cdq();
// Divide edx:eax by right.
__ idiv(right);
// Check for the corner case of dividing the most negative smi by
// -1. We cannot use the overflow flag, since it is not set by idiv
// instruction.
ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ cmp(eax, 0x40000000);
__ j(equal, &use_fp_on_smis);
// Check for negative zero result. Use combined = left | right.
__ NegativeZeroTest(eax, combined, &use_fp_on_smis);
// Check that the remainder is zero.
__ test(edx, Operand(edx));
__ j(not_zero, &use_fp_on_smis);
// Tag the result and store it in register eax.
__ SmiTag(eax);
break;
case Token::MOD:
// Check for 0 divisor.
__ test(right, Operand(right));
__ j(zero, ¬_smis, not_taken);
// Sign extend left into edx:eax.
ASSERT(left.is(eax));
__ cdq();
// Divide edx:eax by right.
__ idiv(right);
// Check for negative zero result. Use combined = left | right.
__ NegativeZeroTest(edx, combined, slow);
// Move remainder to register eax.
__ mov(eax, edx);
break;
default:
UNREACHABLE();
}
// 5. Emit return of result in eax.
GenerateReturn(masm);
// 6. For some operations emit inline code to perform floating point
// operations on known smis (e.g., if the result of the operation
// overflowed the smi range).
switch (op_) {
case Token::SHL: {
Comment perform_float(masm, "-- Perform float operation on smis");
__ bind(&use_fp_on_smis);
// Result we want is in left == edx, so we can put the allocated heap
// number in eax.
__ AllocateHeapNumber(eax, ecx, ebx, slow);
// Store the result in the HeapNumber and return.
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
__ cvtsi2sd(xmm0, Operand(left));
__ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
} else {
// It's OK to overwrite the right argument on the stack because we
// are about to return.
__ mov(Operand(esp, 1 * kPointerSize), left);
__ fild_s(Operand(esp, 1 * kPointerSize));
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
}
GenerateReturn(masm);
break;
}
case Token::ADD:
case Token::SUB:
case Token::MUL:
case Token::DIV: {
Comment perform_float(masm, "-- Perform float operation on smis");
__ bind(&use_fp_on_smis);
// Restore arguments to edx, eax.
switch (op_) {
case Token::ADD:
// Revert right = right + left.
__ sub(right, Operand(left));
break;
case Token::SUB:
// Revert left = left - right.
__ add(left, Operand(right));
break;
case Token::MUL:
// Right was clobbered but a copy is in ebx.
__ mov(right, ebx);
break;
case Token::DIV:
// Left was clobbered but a copy is in edi. Right is in ebx for
// division.
__ mov(edx, edi);
__ mov(eax, right);
break;
default: UNREACHABLE();
break;
}
__ AllocateHeapNumber(ecx, ebx, no_reg, slow);
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
FloatingPointHelper::LoadSSE2Smis(masm, ebx);
switch (op_) {
case Token::ADD: __ addsd(xmm0, xmm1); break;
case Token::SUB: __ subsd(xmm0, xmm1); break;
case Token::MUL: __ mulsd(xmm0, xmm1); break;
case Token::DIV: __ divsd(xmm0, xmm1); break;
default: UNREACHABLE();
}
__ movdbl(FieldOperand(ecx, HeapNumber::kValueOffset), xmm0);
} else { // SSE2 not available, use FPU.
FloatingPointHelper::LoadFloatSmis(masm, ebx);
switch (op_) {
case Token::ADD: __ faddp(1); break;
case Token::SUB: __ fsubp(1); break;
case Token::MUL: __ fmulp(1); break;
case Token::DIV: __ fdivp(1); break;
default: UNREACHABLE();
}
__ fstp_d(FieldOperand(ecx, HeapNumber::kValueOffset));
}
__ mov(eax, ecx);
GenerateReturn(masm);
break;
}
default:
break;
}
// 7. Non-smi operands, fall out to the non-smi code with the operands in
// edx and eax.
Comment done_comment(masm, "-- Enter non-smi code");
__ bind(¬_smis);
switch (op_) {
case Token::BIT_OR:
case Token::SHL:
case Token::SAR:
case Token::SHR:
// Right operand is saved in ecx and eax was destroyed by the smi
// check.
__ mov(eax, ecx);
break;
case Token::DIV:
case Token::MOD:
// Operands are in eax, ebx at this point.
__ mov(edx, eax);
__ mov(eax, ebx);
break;
default:
break;
}
}
void GenericBinaryOpStub::Generate(MacroAssembler* masm) {
Label call_runtime;
__ IncrementCounter(&Counters::generic_binary_stub_calls, 1);
// Generate fast case smi code if requested. This flag is set when the fast
// case smi code is not generated by the caller. Generating it here will speed
// up common operations.
if (HasSmiCodeInStub()) {
GenerateSmiCode(masm, &call_runtime);
} else if (op_ != Token::MOD) { // MOD goes straight to runtime.
GenerateLoadArguments(masm);
}
// Floating point case.
switch (op_) {
case Token::ADD:
case Token::SUB:
case Token::MUL:
case Token::DIV: {
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
if (NumberInfo::IsNumber(operands_type_)) {
if (FLAG_debug_code) {
// Assert at runtime that inputs are only numbers.
__ AbortIfNotNumber(edx,
"GenericBinaryOpStub operand not a number.");
__ AbortIfNotNumber(eax,
"GenericBinaryOpStub operand not a number.");
}
FloatingPointHelper::LoadSSE2Operands(masm);
} else {
FloatingPointHelper::LoadSSE2Operands(masm, &call_runtime);
}
switch (op_) {
case Token::ADD: __ addsd(xmm0, xmm1); break;
case Token::SUB: __ subsd(xmm0, xmm1); break;
case Token::MUL: __ mulsd(xmm0, xmm1); break;
case Token::DIV: __ divsd(xmm0, xmm1); break;
default: UNREACHABLE();
}
GenerateHeapResultAllocation(masm, &call_runtime);
__ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
GenerateReturn(masm);
} else { // SSE2 not available, use FPU.
if (NumberInfo::IsNumber(operands_type_)) {
if (FLAG_debug_code) {
// Assert at runtime that inputs are only numbers.
__ AbortIfNotNumber(edx,
"GenericBinaryOpStub operand not a number.");
__ AbortIfNotNumber(eax,
"GenericBinaryOpStub operand not a number.");
}
} else {
FloatingPointHelper::CheckFloatOperands(masm, &call_runtime, ebx);
}
FloatingPointHelper::LoadFloatOperands(
masm,
ecx,
FloatingPointHelper::ARGS_IN_REGISTERS);
switch (op_) {
case Token::ADD: __ faddp(1); break;
case Token::SUB: __ fsubp(1); break;
case Token::MUL: __ fmulp(1); break;
case Token::DIV: __ fdivp(1); break;
default: UNREACHABLE();
}
Label after_alloc_failure;
GenerateHeapResultAllocation(masm, &after_alloc_failure);
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
GenerateReturn(masm);
__ bind(&after_alloc_failure);
__ ffree();
__ jmp(&call_runtime);
}
}
case Token::MOD: {
// For MOD we go directly to runtime in the non-smi case.
break;
}
case Token::BIT_OR:
case Token::BIT_AND:
case Token::BIT_XOR:
case Token::SAR:
case Token::SHL:
case Token::SHR: {
Label non_smi_result;
FloatingPointHelper::LoadAsIntegers(masm, use_sse3_, &call_runtime);
switch (op_) {
case Token::BIT_OR: __ or_(eax, Operand(ecx)); break;
case Token::BIT_AND: __ and_(eax, Operand(ecx)); break;
case Token::BIT_XOR: __ xor_(eax, Operand(ecx)); break;
case Token::SAR: __ sar_cl(eax); break;
case Token::SHL: __ shl_cl(eax); break;
case Token::SHR: __ shr_cl(eax); break;
default: UNREACHABLE();
}
if (op_ == Token::SHR) {
// Check if result is non-negative and fits in a smi.
__ test(eax, Immediate(0xc0000000));
__ j(not_zero, &call_runtime);
} else {
// Check if result fits in a smi.
__ cmp(eax, 0xc0000000);
__ j(negative, &non_smi_result);
}
// Tag smi result and return.
__ SmiTag(eax);
GenerateReturn(masm);
// All ops except SHR return a signed int32 that we load in a HeapNumber.
if (op_ != Token::SHR) {
__ bind(&non_smi_result);
// Allocate a heap number if needed.
__ mov(ebx, Operand(eax)); // ebx: result
Label skip_allocation;
switch (mode_) {
case OVERWRITE_LEFT:
case OVERWRITE_RIGHT:
// If the operand was an object, we skip the
// allocation of a heap number.
__ mov(eax, Operand(esp, mode_ == OVERWRITE_RIGHT ?
1 * kPointerSize : 2 * kPointerSize));
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Fall through!
case NO_OVERWRITE:
__ AllocateHeapNumber(eax, ecx, edx, &call_runtime);
__ bind(&skip_allocation);
break;
default: UNREACHABLE();
}
// Store the result in the HeapNumber and return.
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
__ cvtsi2sd(xmm0, Operand(ebx));
__ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
} else {
__ mov(Operand(esp, 1 * kPointerSize), ebx);
__ fild_s(Operand(esp, 1 * kPointerSize));
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
}
GenerateReturn(masm);
}
break;
}
default: UNREACHABLE(); break;
}
// If all else fails, use the runtime system to get the correct
// result. If arguments was passed in registers now place them on the
// stack in the correct order below the return address.
__ bind(&call_runtime);
if (HasArgsInRegisters()) {
__ pop(ecx);
if (HasArgsReversed()) {
__ push(eax);
__ push(edx);
} else {
__ push(edx);
__ push(eax);
}
__ push(ecx);
}
switch (op_) {
case Token::ADD: {
// Test for string arguments before calling runtime.
Label not_strings, not_string1, string1, string1_smi2;
Result answer;
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, ¬_string1);
__ CmpObjectType(edx, FIRST_NONSTRING_TYPE, ecx);
__ j(above_equal, ¬_string1);
// First argument is a string, test second.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &string1_smi2);
__ CmpObjectType(eax, FIRST_NONSTRING_TYPE, ecx);
__ j(above_equal, &string1);
// First and second argument are strings. Jump to the string add stub.
StringAddStub string_add_stub(NO_STRING_CHECK_IN_STUB);
__ TailCallStub(&string_add_stub);
__ bind(&string1_smi2);
// First argument is a string, second is a smi. Try to lookup the number
// string for the smi in the number string cache.
NumberToStringStub::GenerateLookupNumberStringCache(
masm, eax, edi, ebx, ecx, true, &string1);
// Call the string add stub to make the result.
__ EnterInternalFrame();
__ push(edx); // Original first argument.
__ push(edi); // Number to string result for second argument.
__ CallStub(&string_add_stub);
__ LeaveInternalFrame();
__ ret(2 * kPointerSize);
__ bind(&string1);
__ InvokeBuiltin(
HasArgsReversed() ?
Builtins::STRING_ADD_RIGHT :
Builtins::STRING_ADD_LEFT,
JUMP_FUNCTION);
// First argument was not a string, test second.
__ bind(¬_string1);
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, ¬_strings);
__ CmpObjectType(eax, FIRST_NONSTRING_TYPE, ecx);
__ j(above_equal, ¬_strings);
// Only second argument is a string.
__ InvokeBuiltin(
HasArgsReversed() ?
Builtins::STRING_ADD_LEFT :
Builtins::STRING_ADD_RIGHT,
JUMP_FUNCTION);
__ bind(¬_strings);
// Neither argument is a string.
__ InvokeBuiltin(Builtins::ADD, JUMP_FUNCTION);
break;
}
case Token::SUB:
__ InvokeBuiltin(Builtins::SUB, JUMP_FUNCTION);
break;
case Token::MUL:
__ InvokeBuiltin(Builtins::MUL, JUMP_FUNCTION);
break;
case Token::DIV:
__ InvokeBuiltin(Builtins::DIV, JUMP_FUNCTION);
break;
case Token::MOD:
__ InvokeBuiltin(Builtins::MOD, JUMP_FUNCTION);
break;
case Token::BIT_OR:
__ InvokeBuiltin(Builtins::BIT_OR, JUMP_FUNCTION);
break;
case Token::BIT_AND:
__ InvokeBuiltin(Builtins::BIT_AND, JUMP_FUNCTION);
break;
case Token::BIT_XOR:
__ InvokeBuiltin(Builtins::BIT_XOR, JUMP_FUNCTION);
break;
case Token::SAR:
__ InvokeBuiltin(Builtins::SAR, JUMP_FUNCTION);
break;
case Token::SHL:
__ InvokeBuiltin(Builtins::SHL, JUMP_FUNCTION);
break;
case Token::SHR:
__ InvokeBuiltin(Builtins::SHR, JUMP_FUNCTION);
break;
default:
UNREACHABLE();
}
}
void GenericBinaryOpStub::GenerateHeapResultAllocation(MacroAssembler* masm,
Label* alloc_failure) {
Label skip_allocation;
OverwriteMode mode = mode_;
if (HasArgsReversed()) {
if (mode == OVERWRITE_RIGHT) {
mode = OVERWRITE_LEFT;
} else if (mode == OVERWRITE_LEFT) {
mode = OVERWRITE_RIGHT;
}
}
switch (mode) {
case OVERWRITE_LEFT: {
// If the argument in edx is already an object, we skip the
// allocation of a heap number.
__ test(edx, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Allocate a heap number for the result. Keep eax and edx intact
// for the possible runtime call.
__ AllocateHeapNumber(ebx, ecx, no_reg, alloc_failure);
// Now edx can be overwritten losing one of the arguments as we are
// now done and will not need it any more.
__ mov(edx, Operand(ebx));
__ bind(&skip_allocation);
// Use object in edx as a result holder
__ mov(eax, Operand(edx));
break;
}
case OVERWRITE_RIGHT:
// If the argument in eax is already an object, we skip the
// allocation of a heap number.
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Fall through!
case NO_OVERWRITE:
// Allocate a heap number for the result. Keep eax and edx intact
// for the possible runtime call.
__ AllocateHeapNumber(ebx, ecx, no_reg, alloc_failure);
// Now eax can be overwritten losing one of the arguments as we are
// now done and will not need it any more.
__ mov(eax, ebx);
__ bind(&skip_allocation);
break;
default: UNREACHABLE();
}
}
void GenericBinaryOpStub::GenerateLoadArguments(MacroAssembler* masm) {
// If arguments are not passed in registers read them from the stack.
if (!HasArgsInRegisters()) {
__ mov(eax, Operand(esp, 1 * kPointerSize));
__ mov(edx, Operand(esp, 2 * kPointerSize));
}
}
void GenericBinaryOpStub::GenerateReturn(MacroAssembler* masm) {
// If arguments are not passed in registers remove them from the stack before
// returning.
if (!HasArgsInRegisters()) {
__ ret(2 * kPointerSize); // Remove both operands
} else {
__ ret(0);
}
}
void TranscendentalCacheStub::Generate(MacroAssembler* masm) {
// Input on stack:
// esp[4]: argument (should be number).
// esp[0]: return address.
// Test that eax is a number.
Label runtime_call;
Label runtime_call_clear_stack;
Label input_not_smi;
Label loaded;
__ mov(eax, Operand(esp, kPointerSize));
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &input_not_smi);
// Input is a smi. Untag and load it onto the FPU stack.
// Then load the low and high words of the double into ebx, edx.
ASSERT_EQ(1, kSmiTagSize);
__ sar(eax, 1);
__ sub(Operand(esp), Immediate(2 * kPointerSize));
__ mov(Operand(esp, 0), eax);
__ fild_s(Operand(esp, 0));
__ fst_d(Operand(esp, 0));
__ pop(edx);
__ pop(ebx);
__ jmp(&loaded);
__ bind(&input_not_smi);
// Check if input is a HeapNumber.
__ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(Operand(ebx), Immediate(Factory::heap_number_map()));
__ j(not_equal, &runtime_call);
// Input is a HeapNumber. Push it on the FPU stack and load its
// low and high words into ebx, edx.
__ fld_d(FieldOperand(eax, HeapNumber::kValueOffset));
__ mov(edx, FieldOperand(eax, HeapNumber::kExponentOffset));
__ mov(ebx, FieldOperand(eax, HeapNumber::kMantissaOffset));
__ bind(&loaded);
// ST[0] == double value
// ebx = low 32 bits of double value
// edx = high 32 bits of double value
// Compute hash:
// h = (low ^ high); h ^= h >> 16; h ^= h >> 8; h = h & (cacheSize - 1);
__ mov(ecx, ebx);
__ xor_(ecx, Operand(edx));
__ mov(eax, ecx);
__ sar(eax, 16);
__ xor_(ecx, Operand(eax));
__ mov(eax, ecx);
__ sar(eax, 8);
__ xor_(ecx, Operand(eax));
ASSERT(IsPowerOf2(TranscendentalCache::kCacheSize));
__ and_(Operand(ecx), Immediate(TranscendentalCache::kCacheSize - 1));
// ST[0] == double value.
// ebx = low 32 bits of double value.
// edx = high 32 bits of double value.
// ecx = TranscendentalCache::hash(double value).
__ mov(eax,
Immediate(ExternalReference::transcendental_cache_array_address()));
// Eax points to cache array.
__ mov(eax, Operand(eax, type_ * sizeof(TranscendentalCache::caches_[0])));
// Eax points to the cache for the type type_.
// If NULL, the cache hasn't been initialized yet, so go through runtime.
__ test(eax, Operand(eax));
__ j(zero, &runtime_call_clear_stack);
#ifdef DEBUG
// Check that the layout of cache elements match expectations.
{ // NOLINT - doesn't like a single brace on a line.
TranscendentalCache::Element test_elem[2];
char* elem_start = reinterpret_cast<char*>(&test_elem[0]);
char* elem2_start = reinterpret_cast<char*>(&test_elem[1]);
char* elem_in0 = reinterpret_cast<char*>(&(test_elem[0].in[0]));
char* elem_in1 = reinterpret_cast<char*>(&(test_elem[0].in[1]));
char* elem_out = reinterpret_cast<char*>(&(test_elem[0].output));
CHECK_EQ(12, elem2_start - elem_start); // Two uint_32's and a pointer.
CHECK_EQ(0, elem_in0 - elem_start);
CHECK_EQ(kIntSize, elem_in1 - elem_start);
CHECK_EQ(2 * kIntSize, elem_out - elem_start);
}
#endif
// Find the address of the ecx'th entry in the cache, i.e., &eax[ecx*12].
__ lea(ecx, Operand(ecx, ecx, times_2, 0));
__ lea(ecx, Operand(eax, ecx, times_4, 0));
// Check if cache matches: Double value is stored in uint32_t[2] array.
Label cache_miss;
__ cmp(ebx, Operand(ecx, 0));
__ j(not_equal, &cache_miss);
__ cmp(edx, Operand(ecx, kIntSize));
__ j(not_equal, &cache_miss);
// Cache hit!
__ mov(eax, Operand(ecx, 2 * kIntSize));
__ fstp(0);
__ ret(kPointerSize);
__ bind(&cache_miss);
// Update cache with new value.
// We are short on registers, so use no_reg as scratch.
// This gives slightly larger code.
__ AllocateHeapNumber(eax, edi, no_reg, &runtime_call_clear_stack);
GenerateOperation(masm);
__ mov(Operand(ecx, 0), ebx);
__ mov(Operand(ecx, kIntSize), edx);
__ mov(Operand(ecx, 2 * kIntSize), eax);
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
__ ret(kPointerSize);
__ bind(&runtime_call_clear_stack);
__ fstp(0);
__ bind(&runtime_call);
__ TailCallRuntime(ExternalReference(RuntimeFunction()), 1, 1);
}
Runtime::FunctionId TranscendentalCacheStub::RuntimeFunction() {
switch (type_) {
// Add more cases when necessary.
case TranscendentalCache::SIN: return Runtime::kMath_sin;
case TranscendentalCache::COS: return Runtime::kMath_cos;
default:
UNIMPLEMENTED();
return Runtime::kAbort;
}
}
void TranscendentalCacheStub::GenerateOperation(MacroAssembler* masm) {
// Only free register is edi.
Label done;
ASSERT(type_ == TranscendentalCache::SIN ||
type_ == TranscendentalCache::COS);
// More transcendental types can be added later.
// Both fsin and fcos require arguments in the range +/-2^63 and
// return NaN for infinities and NaN. They can share all code except
// the actual fsin/fcos operation.
Label in_range;
// If argument is outside the range -2^63..2^63, fsin/cos doesn't
// work. We must reduce it to the appropriate range.
__ mov(edi, edx);
__ and_(Operand(edi), Immediate(0x7ff00000)); // Exponent only.
int supported_exponent_limit =
(63 + HeapNumber::kExponentBias) << HeapNumber::kExponentShift;
__ cmp(Operand(edi), Immediate(supported_exponent_limit));
__ j(below, &in_range, taken);
// Check for infinity and NaN. Both return NaN for sin.
__ cmp(Operand(edi), Immediate(0x7ff00000));
Label non_nan_result;
__ j(not_equal, &non_nan_result, taken);
// Input is +/-Infinity or NaN. Result is NaN.
__ fstp(0);
// NaN is represented by 0x7ff8000000000000.
__ push(Immediate(0x7ff80000));
__ push(Immediate(0));
__ fld_d(Operand(esp, 0));
__ add(Operand(esp), Immediate(2 * kPointerSize));
__ jmp(&done);
__ bind(&non_nan_result);
// Use fpmod to restrict argument to the range +/-2*PI.
__ mov(edi, eax); // Save eax before using fnstsw_ax.
__ fldpi();
__ fadd(0);
__ fld(1);
// FPU Stack: input, 2*pi, input.
{
Label no_exceptions;
__ fwait();
__ fnstsw_ax();
// Clear if Illegal Operand or Zero Division exceptions are set.
__ test(Operand(eax), Immediate(5));
__ j(zero, &no_exceptions);
__ fnclex();
__ bind(&no_exceptions);
}
// Compute st(0) % st(1)
{
Label partial_remainder_loop;
__ bind(&partial_remainder_loop);
__ fprem1();
__ fwait();
__ fnstsw_ax();
__ test(Operand(eax), Immediate(0x400 /* C2 */));
// If C2 is set, computation only has partial result. Loop to
// continue computation.
__ j(not_zero, &partial_remainder_loop);
}
// FPU Stack: input, 2*pi, input % 2*pi
__ fstp(2);
__ fstp(0);
__ mov(eax, edi); // Restore eax (allocated HeapNumber pointer).
// FPU Stack: input % 2*pi
__ bind(&in_range);
switch (type_) {
case TranscendentalCache::SIN:
__ fsin();
break;
case TranscendentalCache::COS:
__ fcos();
break;
default:
UNREACHABLE();
}
__ bind(&done);
}
// Get the integer part of a heap number. Surprisingly, all this bit twiddling
// is faster than using the built-in instructions on floating point registers.
// Trashes edi and ebx. Dest is ecx. Source cannot be ecx or one of the
// trashed registers.
void IntegerConvert(MacroAssembler* masm,
Register source,
bool use_sse3,
Label* conversion_failure) {
ASSERT(!source.is(ecx) && !source.is(edi) && !source.is(ebx));
Label done, right_exponent, normal_exponent;
Register scratch = ebx;
Register scratch2 = edi;
// Get exponent word.
__ mov(scratch, FieldOperand(source, HeapNumber::kExponentOffset));
// Get exponent alone in scratch2.
__ mov(scratch2, scratch);
__ and_(scratch2, HeapNumber::kExponentMask);
if (use_sse3) {
CpuFeatures::Scope scope(SSE3);
// Check whether the exponent is too big for a 64 bit signed integer.
static const uint32_t kTooBigExponent =
(HeapNumber::kExponentBias + 63) << HeapNumber::kExponentShift;
__ cmp(Operand(scratch2), Immediate(kTooBigExponent));
__ j(greater_equal, conversion_failure);
// Load x87 register with heap number.
__ fld_d(FieldOperand(source, HeapNumber::kValueOffset));
// Reserve space for 64 bit answer.
__ sub(Operand(esp), Immediate(sizeof(uint64_t))); // Nolint.
// Do conversion, which cannot fail because we checked the exponent.
__ fisttp_d(Operand(esp, 0));
__ mov(ecx, Operand(esp, 0)); // Load low word of answer into ecx.
__ add(Operand(esp), Immediate(sizeof(uint64_t))); // Nolint.
} else {
// Load ecx with zero. We use this either for the final shift or
// for the answer.
__ xor_(ecx, Operand(ecx));
// Check whether the exponent matches a 32 bit signed int that cannot be
// represented by a Smi. A non-smi 32 bit integer is 1.xxx * 2^30 so the
// exponent is 30 (biased). This is the exponent that we are fastest at and
// also the highest exponent we can handle here.
const uint32_t non_smi_exponent =
(HeapNumber::kExponentBias + 30) << HeapNumber::kExponentShift;
__ cmp(Operand(scratch2), Immediate(non_smi_exponent));
// If we have a match of the int32-but-not-Smi exponent then skip some
// logic.
__ j(equal, &right_exponent);
// If the exponent is higher than that then go to slow case. This catches
// numbers that don't fit in a signed int32, infinities and NaNs.
__ j(less, &normal_exponent);
{
// Handle a big exponent. The only reason we have this code is that the
// >>> operator has a tendency to generate numbers with an exponent of 31.
const uint32_t big_non_smi_exponent =
(HeapNumber::kExponentBias + 31) << HeapNumber::kExponentShift;
__ cmp(Operand(scratch2), Immediate(big_non_smi_exponent));
__ j(not_equal, conversion_failure);
// We have the big exponent, typically from >>>. This means the number is
// in the range 2^31 to 2^32 - 1. Get the top bits of the mantissa.
__ mov(scratch2, scratch);
__ and_(scratch2, HeapNumber::kMantissaMask);
// Put back the implicit 1.
__ or_(scratch2, 1 << HeapNumber::kExponentShift);
// Shift up the mantissa bits to take up the space the exponent used to
// take. We just orred in the implicit bit so that took care of one and
// we want to use the full unsigned range so we subtract 1 bit from the
// shift distance.
const int big_shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 1;
__ shl(scratch2, big_shift_distance);
// Get the second half of the double.
__ mov(ecx, FieldOperand(source, HeapNumber::kMantissaOffset));
// Shift down 21 bits to get the most significant 11 bits or the low
// mantissa word.
__ shr(ecx, 32 - big_shift_distance);
__ or_(ecx, Operand(scratch2));
// We have the answer in ecx, but we may need to negate it.
__ test(scratch, Operand(scratch));
__ j(positive, &done);
__ neg(ecx);
__ jmp(&done);
}
__ bind(&normal_exponent);
// Exponent word in scratch, exponent part of exponent word in scratch2.
// Zero in ecx.
// We know the exponent is smaller than 30 (biased). If it is less than
// 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, ie
// it rounds to zero.
const uint32_t zero_exponent =
(HeapNumber::kExponentBias + 0) << HeapNumber::kExponentShift;
__ sub(Operand(scratch2), Immediate(zero_exponent));
// ecx already has a Smi zero.
__ j(less, &done);
// We have a shifted exponent between 0 and 30 in scratch2.
__ shr(scratch2, HeapNumber::kExponentShift);
__ mov(ecx, Immediate(30));
__ sub(ecx, Operand(scratch2));
__ bind(&right_exponent);
// Here ecx is the shift, scratch is the exponent word.
// Get the top bits of the mantissa.
__ and_(scratch, HeapNumber::kMantissaMask);
// Put back the implicit 1.
__ or_(scratch, 1 << HeapNumber::kExponentShift);
// Shift up the mantissa bits to take up the space the exponent used to
// take. We have kExponentShift + 1 significant bits int he low end of the
// word. Shift them to the top bits.
const int shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 2;
__ shl(scratch, shift_distance);
// Get the second half of the double. For some exponents we don't
// actually need this because the bits get shifted out again, but
// it's probably slower to test than just to do it.
__ mov(scratch2, FieldOperand(source, HeapNumber::kMantissaOffset));
// Shift down 22 bits to get the most significant 10 bits or the low
// mantissa word.
__ shr(scratch2, 32 - shift_distance);
__ or_(scratch2, Operand(scratch));
// Move down according to the exponent.
__ shr_cl(scratch2);
// Now the unsigned answer is in scratch2. We need to move it to ecx and
// we may need to fix the sign.
Label negative;
__ xor_(ecx, Operand(ecx));
__ cmp(ecx, FieldOperand(source, HeapNumber::kExponentOffset));
__ j(greater, &negative);
__ mov(ecx, scratch2);
__ jmp(&done);
__ bind(&negative);
__ sub(ecx, Operand(scratch2));
__ bind(&done);
}
}
// Input: edx, eax are the left and right objects of a bit op.
// Output: eax, ecx are left and right integers for a bit op.
void FloatingPointHelper::LoadAsIntegers(MacroAssembler* masm,
bool use_sse3,
Label* conversion_failure) {
// Check float operands.
Label arg1_is_object, check_undefined_arg1;
Label arg2_is_object, check_undefined_arg2;
Label load_arg2, done;
__ test(edx, Immediate(kSmiTagMask));
__ j(not_zero, &arg1_is_object);
__ SmiUntag(edx);
__ jmp(&load_arg2);
// If the argument is undefined it converts to zero (ECMA-262, section 9.5).
__ bind(&check_undefined_arg1);
__ cmp(edx, Factory::undefined_value());
__ j(not_equal, conversion_failure);
__ mov(edx, Immediate(0));
__ jmp(&load_arg2);
__ bind(&arg1_is_object);
__ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
__ cmp(ebx, Factory::heap_number_map());
__ j(not_equal, &check_undefined_arg1);
// Get the untagged integer version of the edx heap number in ecx.
IntegerConvert(masm, edx, use_sse3, conversion_failure);
__ mov(edx, ecx);
// Here edx has the untagged integer, eax has a Smi or a heap number.
__ bind(&load_arg2);
// Test if arg2 is a Smi.
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &arg2_is_object);
__ SmiUntag(eax);
__ mov(ecx, eax);
__ jmp(&done);
// If the argument is undefined it converts to zero (ECMA-262, section 9.5).
__ bind(&check_undefined_arg2);
__ cmp(eax, Factory::undefined_value());
__ j(not_equal, conversion_failure);
__ mov(ecx, Immediate(0));
__ jmp(&done);
__ bind(&arg2_is_object);
__ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(ebx, Factory::heap_number_map());
__ j(not_equal, &check_undefined_arg2);
// Get the untagged integer version of the eax heap number in ecx.
IntegerConvert(masm, eax, use_sse3, conversion_failure);
__ bind(&done);
__ mov(eax, edx);
}
void FloatingPointHelper::LoadFloatOperand(MacroAssembler* masm,
Register number) {
Label load_smi, done;
__ test(number, Immediate(kSmiTagMask));
__ j(zero, &load_smi, not_taken);
__ fld_d(FieldOperand(number, HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&load_smi);
__ SmiUntag(number);
__ push(number);
__ fild_s(Operand(esp, 0));
__ pop(number);
__ bind(&done);
}
void FloatingPointHelper::LoadSSE2Operands(MacroAssembler* masm) {
Label load_smi_edx, load_eax, load_smi_eax, done;
// Load operand in edx into xmm0.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &load_smi_edx, not_taken); // Argument in edx is a smi.
__ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
__ bind(&load_eax);
// Load operand in eax into xmm1.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &load_smi_eax, not_taken); // Argument in eax is a smi.
__ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&load_smi_edx);
__ SmiUntag(edx); // Untag smi before converting to float.
__ cvtsi2sd(xmm0, Operand(edx));
__ SmiTag(edx); // Retag smi for heap number overwriting test.
__ jmp(&load_eax);
__ bind(&load_smi_eax);
__ SmiUntag(eax); // Untag smi before converting to float.
__ cvtsi2sd(xmm1, Operand(eax));
__ SmiTag(eax); // Retag smi for heap number overwriting test.
__ bind(&done);
}
void FloatingPointHelper::LoadSSE2Operands(MacroAssembler* masm,
Label* not_numbers) {
Label load_smi_edx, load_eax, load_smi_eax, load_float_eax, done;
// Load operand in edx into xmm0, or branch to not_numbers.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &load_smi_edx, not_taken); // Argument in edx is a smi.
__ cmp(FieldOperand(edx, HeapObject::kMapOffset), Factory::heap_number_map());
__ j(not_equal, not_numbers); // Argument in edx is not a number.
__ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
__ bind(&load_eax);
// Load operand in eax into xmm1, or branch to not_numbers.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &load_smi_eax, not_taken); // Argument in eax is a smi.
__ cmp(FieldOperand(eax, HeapObject::kMapOffset), Factory::heap_number_map());
__ j(equal, &load_float_eax);
__ jmp(not_numbers); // Argument in eax is not a number.
__ bind(&load_smi_edx);
__ SmiUntag(edx); // Untag smi before converting to float.
__ cvtsi2sd(xmm0, Operand(edx));
__ SmiTag(edx); // Retag smi for heap number overwriting test.
__ jmp(&load_eax);
__ bind(&load_smi_eax);
__ SmiUntag(eax); // Untag smi before converting to float.
__ cvtsi2sd(xmm1, Operand(eax));
__ SmiTag(eax); // Retag smi for heap number overwriting test.
__ jmp(&done);
__ bind(&load_float_eax);
__ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
__ bind(&done);
}
void FloatingPointHelper::LoadSSE2Smis(MacroAssembler* masm,
Register scratch) {
const Register left = edx;
const Register right = eax;
__ mov(scratch, left);
ASSERT(!scratch.is(right)); // We're about to clobber scratch.
__ SmiUntag(scratch);
__ cvtsi2sd(xmm0, Operand(scratch));
__ mov(scratch, right);
__ SmiUntag(scratch);
__ cvtsi2sd(xmm1, Operand(scratch));
}
void FloatingPointHelper::LoadFloatOperands(MacroAssembler* masm,
Register scratch,
ArgLocation arg_location) {
Label load_smi_1, load_smi_2, done_load_1, done;
if (arg_location == ARGS_IN_REGISTERS) {
__ mov(scratch, edx);
} else {
__ mov(scratch, Operand(esp, 2 * kPointerSize));
}
__ test(scratch, Immediate(kSmiTagMask));
__ j(zero, &load_smi_1, not_taken);
__ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
__ bind(&done_load_1);
if (arg_location == ARGS_IN_REGISTERS) {
__ mov(scratch, eax);
} else {
__ mov(scratch, Operand(esp, 1 * kPointerSize));
}
__ test(scratch, Immediate(kSmiTagMask));
__ j(zero, &load_smi_2, not_taken);
__ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&load_smi_1);
__ SmiUntag(scratch);
__ push(scratch);
__ fild_s(Operand(esp, 0));
__ pop(scratch);
__ jmp(&done_load_1);
__ bind(&load_smi_2);
__ SmiUntag(scratch);
__ push(scratch);
__ fild_s(Operand(esp, 0));
__ pop(scratch);
__ bind(&done);
}
void FloatingPointHelper::LoadFloatSmis(MacroAssembler* masm,
Register scratch) {
const Register left = edx;
const Register right = eax;
__ mov(scratch, left);
ASSERT(!scratch.is(right)); // We're about to clobber scratch.
__ SmiUntag(scratch);
__ push(scratch);
__ fild_s(Operand(esp, 0));
__ mov(scratch, right);
__ SmiUntag(scratch);
__ mov(Operand(esp, 0), scratch);
__ fild_s(Operand(esp, 0));
__ pop(scratch);
}
void FloatingPointHelper::CheckFloatOperands(MacroAssembler* masm,
Label* non_float,
Register scratch) {
Label test_other, done;
// Test if both operands are floats or smi -> scratch=k_is_float;
// Otherwise scratch = k_not_float.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &test_other, not_taken); // argument in edx is OK
__ mov(scratch, FieldOperand(edx, HeapObject::kMapOffset));
__ cmp(scratch, Factory::heap_number_map());
__ j(not_equal, non_float); // argument in edx is not a number -> NaN
__ bind(&test_other);
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &done); // argument in eax is OK
__ mov(scratch, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(scratch, Factory::heap_number_map());
__ j(not_equal, non_float); // argument in eax is not a number -> NaN
// Fall-through: Both operands are numbers.
__ bind(&done);
}
void GenericUnaryOpStub::Generate(MacroAssembler* masm) {
Label slow, done;
if (op_ == Token::SUB) {
// Check whether the value is a smi.
Label try_float;
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &try_float, not_taken);
// Go slow case if the value of the expression is zero
// to make sure that we switch between 0 and -0.
__ test(eax, Operand(eax));
__ j(zero, &slow, not_taken);
// The value of the expression is a smi that is not zero. Try
// optimistic subtraction '0 - value'.
Label undo;
__ mov(edx, Operand(eax));
__ Set(eax, Immediate(0));
__ sub(eax, Operand(edx));
__ j(overflow, &undo, not_taken);
// If result is a smi we are done.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &done, taken);
// Restore eax and go slow case.
__ bind(&undo);
__ mov(eax, Operand(edx));
__ jmp(&slow);
// Try floating point case.
__ bind(&try_float);
__ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(edx, Factory::heap_number_map());
__ j(not_equal, &slow);
if (overwrite_) {
__ mov(edx, FieldOperand(eax, HeapNumber::kExponentOffset));
__ xor_(edx, HeapNumber::kSignMask); // Flip sign.
__ mov(FieldOperand(eax, HeapNumber::kExponentOffset), edx);
} else {
__ mov(edx, Operand(eax));
// edx: operand
__ AllocateHeapNumber(eax, ebx, ecx, &undo);
// eax: allocated 'empty' number
__ mov(ecx, FieldOperand(edx, HeapNumber::kExponentOffset));
__ xor_(ecx, HeapNumber::kSignMask); // Flip sign.
__ mov(FieldOperand(eax, HeapNumber::kExponentOffset), ecx);
__ mov(ecx, FieldOperand(edx, HeapNumber::kMantissaOffset));
__ mov(FieldOperand(eax, HeapNumber::kMantissaOffset), ecx);
}
} else if (op_ == Token::BIT_NOT) {
// Check if the operand is a heap number.
__ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(edx, Factory::heap_number_map());
__ j(not_equal, &slow, not_taken);
// Convert the heap number in eax to an untagged integer in ecx.
IntegerConvert(masm, eax, CpuFeatures::IsSupported(SSE3), &slow);
// Do the bitwise operation and check if the result fits in a smi.
Label try_float;
__ not_(ecx);
__ cmp(ecx, 0xc0000000);
__ j(sign, &try_float, not_taken);
// Tag the result as a smi and we're done.
ASSERT(kSmiTagSize == 1);
__ lea(eax, Operand(ecx, times_2, kSmiTag));
__ jmp(&done);
// Try to store the result in a heap number.
__ bind(&try_float);
if (!overwrite_) {
// Allocate a fresh heap number, but don't overwrite eax until
// we're sure we can do it without going through the slow case
// that needs the value in eax.
__ AllocateHeapNumber(ebx, edx, edi, &slow);
__ mov(eax, Operand(ebx));
}
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
__ cvtsi2sd(xmm0, Operand(ecx));
__ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
} else {
__ push(ecx);
__ fild_s(Operand(esp, 0));
__ pop(ecx);
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
}
} else {
UNIMPLEMENTED();
}
// Return from the stub.
__ bind(&done);
__ StubReturn(1);
// Handle the slow case by jumping to the JavaScript builtin.
__ bind(&slow);
__ pop(ecx); // pop return address.
__ push(eax);
__ push(ecx); // push return address
switch (op_) {
case Token::SUB:
__ InvokeBuiltin(Builtins::UNARY_MINUS, JUMP_FUNCTION);
break;
case Token::BIT_NOT:
__ InvokeBuiltin(Builtins::BIT_NOT, JUMP_FUNCTION);
break;
default:
UNREACHABLE();
}
}
void ArgumentsAccessStub::GenerateReadLength(MacroAssembler* masm) {
// Check if the calling frame is an arguments adaptor frame.
__ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
// Arguments adaptor case: Read the arguments length from the
// adaptor frame and return it.
// Otherwise nothing to do: The number of formal parameters has already been
// passed in register eax by calling function. Just return it.
if (CpuFeatures::IsSupported(CMOV)) {
CpuFeatures::Scope use_cmov(CMOV);
__ cmov(equal, eax,
Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
} else {
Label exit;
__ j(not_equal, &exit);
__ mov(eax, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ bind(&exit);
}
__ ret(0);
}
void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
// The key is in edx and the parameter count is in eax.
// The displacement is used for skipping the frame pointer on the
// stack. It is the offset of the last parameter (if any) relative
// to the frame pointer.
static const int kDisplacement = 1 * kPointerSize;
// Check that the key is a smi.
Label slow;
__ test(edx, Immediate(kSmiTagMask));
__ j(not_zero, &slow, not_taken);
// Check if the calling frame is an arguments adaptor frame.
Label adaptor;
__ mov(ebx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(ebx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(equal, &adaptor);
// Check index against formal parameters count limit passed in
// through register eax. Use unsigned comparison to get negative
// check for free.
__ cmp(edx, Operand(eax));
__ j(above_equal, &slow, not_taken);
// Read the argument from the stack and return it.
ASSERT(kSmiTagSize == 1 && kSmiTag == 0); // shifting code depends on this
__ lea(ebx, Operand(ebp, eax, times_2, 0));
__ neg(edx);
__ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
__ ret(0);
// Arguments adaptor case: Check index against actual arguments
// limit found in the arguments adaptor frame. Use unsigned
// comparison to get negative check for free.
__ bind(&adaptor);
__ mov(ecx, Operand(ebx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ cmp(edx, Operand(ecx));
__ j(above_equal, &slow, not_taken);
// Read the argument from the stack and return it.
ASSERT(kSmiTagSize == 1 && kSmiTag == 0); // shifting code depends on this
__ lea(ebx, Operand(ebx, ecx, times_2, 0));
__ neg(edx);
__ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
__ ret(0);
// Slow-case: Handle non-smi or out-of-bounds access to arguments
// by calling the runtime system.
__ bind(&slow);
__ pop(ebx); // Return address.
__ push(edx);
__ push(ebx);
__ TailCallRuntime(ExternalReference(Runtime::kGetArgumentsProperty), 1, 1);
}
void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* masm) {
// esp[0] : return address
// esp[4] : number of parameters
// esp[8] : receiver displacement
// esp[16] : function
// The displacement is used for skipping the return address and the
// frame pointer on the stack. It is the offset of the last
// parameter (if any) relative to the frame pointer.
static const int kDisplacement = 2 * kPointerSize;
// Check if the calling frame is an arguments adaptor frame.
Label adaptor_frame, try_allocate, runtime;
__ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(equal, &adaptor_frame);
// Get the length from the frame.
__ mov(ecx, Operand(esp, 1 * kPointerSize));
__ jmp(&try_allocate);
// Patch the arguments.length and the parameters pointer.
__ bind(&adaptor_frame);
__ mov(ecx, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ mov(Operand(esp, 1 * kPointerSize), ecx);
__ lea(edx, Operand(edx, ecx, times_2, kDisplacement));
__ mov(Operand(esp, 2 * kPointerSize), edx);
// Try the new space allocation. Start out with computing the size of
// the arguments object and the elements array.
Label add_arguments_object;
__ bind(&try_allocate);
__ test(ecx, Operand(ecx));
__ j(zero, &add_arguments_object);
__ lea(ecx, Operand(ecx, times_2, FixedArray::kHeaderSize));
__ bind(&add_arguments_object);
__ add(Operand(ecx), Immediate(Heap::kArgumentsObjectSize));
// Do the allocation of both objects in one go.
__ AllocateInNewSpace(ecx, eax, edx, ebx, &runtime, TAG_OBJECT);
// Get the arguments boilerplate from the current (global) context.
int offset = Context::SlotOffset(Context::ARGUMENTS_BOILERPLATE_INDEX);
__ mov(edi, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ mov(edi, FieldOperand(edi, GlobalObject::kGlobalContextOffset));
__ mov(edi, Operand(edi, offset));
// Copy the JS object part.
for (int i = 0; i < JSObject::kHeaderSize; i += kPointerSize) {
__ mov(ebx, FieldOperand(edi, i));
__ mov(FieldOperand(eax, i), ebx);
}
// Setup the callee in-object property.
ASSERT(Heap::arguments_callee_index == 0);
__ mov(ebx, Operand(esp, 3 * kPointerSize));
__ mov(FieldOperand(eax, JSObject::kHeaderSize), ebx);
// Get the length (smi tagged) and set that as an in-object property too.
ASSERT(Heap::arguments_length_index == 1);
__ mov(ecx, Operand(esp, 1 * kPointerSize));
__ mov(FieldOperand(eax, JSObject::kHeaderSize + kPointerSize), ecx);
// If there are no actual arguments, we're done.
Label done;
__ test(ecx, Operand(ecx));
__ j(zero, &done);
// Get the parameters pointer from the stack and untag the length.
__ mov(edx, Operand(esp, 2 * kPointerSize));
__ SmiUntag(ecx);
// Setup the elements pointer in the allocated arguments object and
// initialize the header in the elements fixed array.
__ lea(edi, Operand(eax, Heap::kArgumentsObjectSize));
__ mov(FieldOperand(eax, JSObject::kElementsOffset), edi);
__ mov(FieldOperand(edi, FixedArray::kMapOffset),
Immediate(Factory::fixed_array_map()));
__ mov(FieldOperand(edi, FixedArray::kLengthOffset), ecx);
// Copy the fixed array slots.
Label loop;
__ bind(&loop);
__ mov(ebx, Operand(edx, -1 * kPointerSize)); // Skip receiver.
__ mov(FieldOperand(edi, FixedArray::kHeaderSize), ebx);
__ add(Operand(edi), Immediate(kPointerSize));
__ sub(Operand(edx), Immediate(kPointerSize));
__ dec(ecx);
__ j(not_zero, &loop);
// Return and remove the on-stack parameters.
__ bind(&done);
__ ret(3 * kPointerSize);
// Do the runtime call to allocate the arguments object.
__ bind(&runtime);
__ TailCallRuntime(ExternalReference(Runtime::kNewArgumentsFast), 3, 1);
}
void RegExpExecStub::Generate(MacroAssembler* masm) {
// Just jump directly to runtime if native RegExp is not selected at compile
// time or if regexp entry in generated code is turned off runtime switch or
// at compilation.
#ifndef V8_NATIVE_REGEXP
__ TailCallRuntime(ExternalReference(Runtime::kRegExpExec), 4, 1);
#else // V8_NATIVE_REGEXP
if (!FLAG_regexp_entry_native) {
__ TailCallRuntime(ExternalReference(Runtime::kRegExpExec), 4, 1);
return;
}
// Stack frame on entry.
// esp[0]: return address
// esp[4]: last_match_info (expected JSArray)
// esp[8]: previous index
// esp[12]: subject string
// esp[16]: JSRegExp object
static const int kLastMatchInfoOffset = 1 * kPointerSize;
static const int kPreviousIndexOffset = 2 * kPointerSize;
static const int kSubjectOffset = 3 * kPointerSize;
static const int kJSRegExpOffset = 4 * kPointerSize;
Label runtime, invoke_regexp;
// Ensure that a RegExp stack is allocated.
ExternalReference address_of_regexp_stack_memory_address =
ExternalReference::address_of_regexp_stack_memory_address();
ExternalReference address_of_regexp_stack_memory_size =
ExternalReference::address_of_regexp_stack_memory_size();
__ mov(ebx, Operand::StaticVariable(address_of_regexp_stack_memory_size));
__ test(ebx, Operand(ebx));
__ j(zero, &runtime, not_taken);
// Check that the first argument is a JSRegExp object.
__ mov(eax, Operand(esp, kJSRegExpOffset));
ASSERT_EQ(0, kSmiTag);
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &runtime);
__ CmpObjectType(eax, JS_REGEXP_TYPE, ecx);
__ j(not_equal, &runtime);
// Check that the RegExp has been compiled (data contains a fixed array).
__ mov(ecx, FieldOperand(eax, JSRegExp::kDataOffset));
if (FLAG_debug_code) {
__ test(ecx, Immediate(kSmiTagMask));
__ Check(not_zero, "Unexpected type for RegExp data, FixedArray expected");
__ CmpObjectType(ecx, FIXED_ARRAY_TYPE, ebx);
__ Check(equal, "Unexpected type for RegExp data, FixedArray expected");
}
// ecx: RegExp data (FixedArray)
// Check the type of the RegExp. Only continue if type is JSRegExp::IRREGEXP.
__ mov(ebx, FieldOperand(ecx, JSRegExp::kDataTagOffset));
__ cmp(Operand(ebx), Immediate(Smi::FromInt(JSRegExp::IRREGEXP)));
__ j(not_equal, &runtime);
// ecx: RegExp data (FixedArray)
// Check that the number of captures fit in the static offsets vector buffer.
__ mov(edx, FieldOperand(ecx, JSRegExp::kIrregexpCaptureCountOffset));
// Calculate number of capture registers (number_of_captures + 1) * 2. This
// uses the asumption that smis are 2 * their untagged value.
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(1, kSmiTagSize + kSmiShiftSize);
__ add(Operand(edx), Immediate(2)); // edx was a smi.
// Check that the static offsets vector buffer is large enough.
__ cmp(edx, OffsetsVector::kStaticOffsetsVectorSize);
__ j(above, &runtime);
// ecx: RegExp data (FixedArray)
// edx: Number of capture registers
// Check that the second argument is a string.
__ mov(eax, Operand(esp, kSubjectOffset));
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &runtime);
Condition is_string = masm->IsObjectStringType(eax, ebx, ebx);
__ j(NegateCondition(is_string), &runtime);
// Get the length of the string to ebx.
__ mov(ebx, FieldOperand(eax, String::kLengthOffset));
// ebx: Length of subject string
// ecx: RegExp data (FixedArray)
// edx: Number of capture registers
// Check that the third argument is a positive smi.
// Check that the third argument is a positive smi less than the subject
// string length. A negative value will be greater (usigned comparison).
__ mov(eax, Operand(esp, kPreviousIndexOffset));
__ SmiUntag(eax);
__ cmp(eax, Operand(ebx));
__ j(above, &runtime);
// ecx: RegExp data (FixedArray)
// edx: Number of capture registers
// Check that the fourth object is a JSArray object.
__ mov(eax, Operand(esp, kLastMatchInfoOffset));
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &runtime);
__ CmpObjectType(eax, JS_ARRAY_TYPE, ebx);
__ j(not_equal, &runtime);
// Check that the JSArray is in fast case.
__ mov(ebx, FieldOperand(eax, JSArray::kElementsOffset));
__ mov(eax, FieldOperand(ebx, HeapObject::kMapOffset));
__ cmp(eax, Factory::fixed_array_map());
__ j(not_equal, &runtime);
// Check that the last match info has space for the capture registers and the
// additional information.
__ mov(eax, FieldOperand(ebx, FixedArray::kLengthOffset));
__ add(Operand(edx), Immediate(RegExpImpl::kLastMatchOverhead));
__ cmp(edx, Operand(eax));
__ j(greater, &runtime);
// ecx: RegExp data (FixedArray)
// Check the representation and encoding of the subject string.
Label seq_string, seq_two_byte_string, check_code;
const int kStringRepresentationEncodingMask =
kIsNotStringMask | kStringRepresentationMask | kStringEncodingMask;
__ mov(eax, Operand(esp, kSubjectOffset));
__ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ebx, FieldOperand(ebx, Map::kInstanceTypeOffset));
__ and_(ebx, kStringRepresentationEncodingMask);
// First check for sequential string.
ASSERT_EQ(0, kStringTag);
ASSERT_EQ(0, kSeqStringTag);
__ test(Operand(ebx),
Immediate(kIsNotStringMask | kStringRepresentationMask));
__ j(zero, &seq_string);
// Check for flat cons string.
// A flat cons string is a cons string where the second part is the empty
// string. In that case the subject string is just the first part of the cons
// string. Also in this case the first part of the cons string is known to be
// a sequential string or an external string.
__ mov(edx, ebx);
__ and_(edx, kStringRepresentationMask);
__ cmp(edx, kConsStringTag);
__ j(not_equal, &runtime);
__ mov(edx, FieldOperand(eax, ConsString::kSecondOffset));
__ cmp(Operand(edx), Factory::empty_string());
__ j(not_equal, &runtime);
__ mov(eax, FieldOperand(eax, ConsString::kFirstOffset));
__ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ebx, FieldOperand(ebx, Map::kInstanceTypeOffset));
ASSERT_EQ(0, kSeqStringTag);
__ test(ebx, Immediate(kStringRepresentationMask));
__ j(not_zero, &runtime);
__ and_(ebx, kStringRepresentationEncodingMask);
__ bind(&seq_string);
// eax: subject string (sequential either ascii to two byte)
// ebx: suject string type & kStringRepresentationEncodingMask
// ecx: RegExp data (FixedArray)
// Check that the irregexp code has been generated for an ascii string. If
// it has, the field contains a code object otherwise it contains the hole.
__ cmp(ebx, kStringTag | kSeqStringTag | kTwoByteStringTag);
__ j(equal, &seq_two_byte_string);
if (FLAG_debug_code) {
__ cmp(ebx, kStringTag | kSeqStringTag | kAsciiStringTag);
__ Check(equal, "Expected sequential ascii string");
}
__ mov(edx, FieldOperand(ecx, JSRegExp::kDataAsciiCodeOffset));
__ Set(edi, Immediate(1)); // Type is ascii.
__ jmp(&check_code);
__ bind(&seq_two_byte_string);
// eax: subject string
// ecx: RegExp data (FixedArray)
__ mov(edx, FieldOperand(ecx, JSRegExp::kDataUC16CodeOffset));
__ Set(edi, Immediate(0)); // Type is two byte.
__ bind(&check_code);
// Check that the irregexp code has been generated for the actual string
// encoding. If it has, the field contains a code object otherwise it contains
// the hole.
__ CmpObjectType(edx, CODE_TYPE, ebx);
__ j(not_equal, &runtime);
// eax: subject string
// edx: code
// edi: encoding of subject string (1 if ascii, 0 if two_byte);
// Load used arguments before starting to push arguments for call to native
// RegExp code to avoid handling changing stack height.
__ mov(ebx, Operand(esp, kPreviousIndexOffset));
__ SmiUntag(ebx); // Previous index from smi.
// eax: subject string
// ebx: previous index
// edx: code
// edi: encoding of subject string (1 if ascii 0 if two_byte);
// All checks done. Now push arguments for native regexp code.
__ IncrementCounter(&Counters::regexp_entry_native, 1);
// Argument 7: Indicate that this is a direct call from JavaScript.
__ push(Immediate(1));
// Argument 6: Start (high end) of backtracking stack memory area.
__ mov(ecx, Operand::StaticVariable(address_of_regexp_stack_memory_address));
__ add(ecx, Operand::StaticVariable(address_of_regexp_stack_memory_size));
__ push(ecx);
// Argument 5: static offsets vector buffer.
__ push(Immediate(ExternalReference::address_of_static_offsets_vector()));
// Argument 4: End of string data
// Argument 3: Start of string data
Label push_two_byte, push_rest;
__ test(edi, Operand(edi));
__ mov(edi, FieldOperand(eax, String::kLengthOffset));
__ j(zero, &push_two_byte);
__ lea(ecx, FieldOperand(eax, edi, times_1, SeqAsciiString::kHeaderSize));
__ push(ecx); // Argument 4.
__ lea(ecx, FieldOperand(eax, ebx, times_1, SeqAsciiString::kHeaderSize));
__ push(ecx); // Argument 3.
__ jmp(&push_rest);
__ bind(&push_two_byte);
__ lea(ecx, FieldOperand(eax, edi, times_2, SeqTwoByteString::kHeaderSize));
__ push(ecx); // Argument 4.
__ lea(ecx, FieldOperand(eax, ebx, times_2, SeqTwoByteString::kHeaderSize));
__ push(ecx); // Argument 3.
__ bind(&push_rest);
// Argument 2: Previous index.
__ push(ebx);
// Argument 1: Subject string.
__ push(eax);
// Locate the code entry and call it.
__ add(Operand(edx), Immediate(Code::kHeaderSize - kHeapObjectTag));
__ call(Operand(edx));
// Remove arguments.
__ add(Operand(esp), Immediate(7 * kPointerSize));
// Check the result.
Label success;
__ cmp(eax, NativeRegExpMacroAssembler::SUCCESS);
__ j(equal, &success, taken);
Label failure;
__ cmp(eax, NativeRegExpMacroAssembler::FAILURE);
__ j(equal, &failure, taken);
__ cmp(eax, NativeRegExpMacroAssembler::EXCEPTION);
// If not exception it can only be retry. Handle that in the runtime system.
__ j(not_equal, &runtime);
// Result must now be exception. If there is no pending exception already a
// stack overflow (on the backtrack stack) was detected in RegExp code but
// haven't created the exception yet. Handle that in the runtime system.
// TODO(592) Rerunning the RegExp to get the stack overflow exception.
ExternalReference pending_exception(Top::k_pending_exception_address);
__ mov(eax,
Operand::StaticVariable(ExternalReference::the_hole_value_location()));
__ cmp(eax, Operand::StaticVariable(pending_exception));
__ j(equal, &runtime);
__ bind(&failure);
// For failure and exception return null.
__ mov(Operand(eax), Factory::null_value());
__ ret(4 * kPointerSize);
// Load RegExp data.
__ bind(&success);
__ mov(eax, Operand(esp, kJSRegExpOffset));
__ mov(ecx, FieldOperand(eax, JSRegExp::kDataOffset));
__ mov(edx, FieldOperand(ecx, JSRegExp::kIrregexpCaptureCountOffset));
// Calculate number of capture registers (number_of_captures + 1) * 2.
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(1, kSmiTagSize + kSmiShiftSize);
__ add(Operand(edx), Immediate(2)); // edx was a smi.
// edx: Number of capture registers
// Load last_match_info which is still known to be a fast case JSArray.
__ mov(eax, Operand(esp, kLastMatchInfoOffset));
__ mov(ebx, FieldOperand(eax, JSArray::kElementsOffset));
// ebx: last_match_info backing store (FixedArray)
// edx: number of capture registers
// Store the capture count.
__ SmiTag(edx); // Number of capture registers to smi.
__ mov(FieldOperand(ebx, RegExpImpl::kLastCaptureCountOffset), edx);
__ SmiUntag(edx); // Number of capture registers back from smi.
// Store last subject and last input.
__ mov(eax, Operand(esp, kSubjectOffset));
__ mov(FieldOperand(ebx, RegExpImpl::kLastSubjectOffset), eax);
__ mov(ecx, ebx);
__ RecordWrite(ecx, RegExpImpl::kLastSubjectOffset, eax, edi);
__ mov(eax, Operand(esp, kSubjectOffset));
__ mov(FieldOperand(ebx, RegExpImpl::kLastInputOffset), eax);
__ mov(ecx, ebx);
__ RecordWrite(ecx, RegExpImpl::kLastInputOffset, eax, edi);
// Get the static offsets vector filled by the native regexp code.
ExternalReference address_of_static_offsets_vector =
ExternalReference::address_of_static_offsets_vector();
__ mov(ecx, Immediate(address_of_static_offsets_vector));
// ebx: last_match_info backing store (FixedArray)
// ecx: offsets vector
// edx: number of capture registers
Label next_capture, done;
__ mov(eax, Operand(esp, kPreviousIndexOffset));
// Capture register counter starts from number of capture registers and
// counts down until wraping after zero.
__ bind(&next_capture);
__ sub(Operand(edx), Immediate(1));
__ j(negative, &done);
// Read the value from the static offsets vector buffer.
__ mov(edi, Operand(ecx, edx, times_int_size, 0));
// Perform explicit shift
ASSERT_EQ(0, kSmiTag);
__ shl(edi, kSmiTagSize);
// Add previous index (from its stack slot) if value is not negative.
Label capture_negative;
// Carry flag set by shift above.
__ j(negative, &capture_negative, not_taken);
__ add(edi, Operand(eax)); // Add previous index (adding smi to smi).
__ bind(&capture_negative);
// Store the smi value in the last match info.
__ mov(FieldOperand(ebx,
edx,
times_pointer_size,
RegExpImpl::kFirstCaptureOffset),
edi);
__ jmp(&next_capture);
__ bind(&done);
// Return last match info.
__ mov(eax, Operand(esp, kLastMatchInfoOffset));
__ ret(4 * kPointerSize);
// Do the runtime call to execute the regexp.
__ bind(&runtime);
__ TailCallRuntime(ExternalReference(Runtime::kRegExpExec), 4, 1);
#endif // V8_NATIVE_REGEXP
}
void NumberToStringStub::GenerateLookupNumberStringCache(MacroAssembler* masm,
Register object,
Register result,
Register scratch1,
Register scratch2,
bool object_is_smi,
Label* not_found) {
// Currently only lookup for smis. Check for smi if object is not known to be
// a smi.
if (!object_is_smi) {
ASSERT(kSmiTag == 0);
__ test(object, Immediate(kSmiTagMask));
__ j(not_zero, not_found);
}
// Use of registers. Register result is used as a temporary.
Register number_string_cache = result;
Register mask = scratch1;
Register scratch = scratch2;
// Load the number string cache.
ExternalReference roots_address = ExternalReference::roots_address();
__ mov(scratch, Immediate(Heap::kNumberStringCacheRootIndex));
__ mov(number_string_cache,
Operand::StaticArray(scratch, times_pointer_size, roots_address));
// Make the hash mask from the length of the number string cache. It
// contains two elements (number and string) for each cache entry.
__ mov(mask, FieldOperand(number_string_cache, FixedArray::kLengthOffset));
__ shr(mask, 1); // Divide length by two (length is not a smi).
__ sub(Operand(mask), Immediate(1)); // Make mask.
// Calculate the entry in the number string cache. The hash value in the
// number string cache for smis is just the smi value.
__ mov(scratch, object);
__ SmiUntag(scratch);
__ and_(scratch, Operand(mask));
// Check if the entry is the smi we are looking for.
__ cmp(object,
FieldOperand(number_string_cache,
scratch,
times_twice_pointer_size,
FixedArray::kHeaderSize));
__ j(not_equal, not_found);
// Get the result from the cache.
__ mov(result,
FieldOperand(number_string_cache,
scratch,
times_twice_pointer_size,
FixedArray::kHeaderSize + kPointerSize));
__ IncrementCounter(&Counters::number_to_string_native, 1);
}
void NumberToStringStub::Generate(MacroAssembler* masm) {
Label runtime;
__ mov(ebx, Operand(esp, kPointerSize));
// Generate code to lookup number in the number string cache.
GenerateLookupNumberStringCache(masm, ebx, eax, ecx, edx, false, &runtime);
__ ret(1 * kPointerSize);
__ bind(&runtime);
// Handle number to string in the runtime system if not found in the cache.
__ TailCallRuntime(ExternalReference(Runtime::kNumberToString), 1, 1);
}
void CompareStub::Generate(MacroAssembler* masm) {
Label call_builtin, done;
// NOTICE! This code is only reached after a smi-fast-case check, so
// it is certain that at least one operand isn't a smi.
if (cc_ == equal) { // Both strict and non-strict.
Label slow; // Fallthrough label.
// Equality is almost reflexive (everything but NaN), so start by testing
// for "identity and not NaN".
{
Label not_identical;
__ cmp(eax, Operand(edx));
__ j(not_equal, ¬_identical);
// Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
// so we do the second best thing - test it ourselves.
if (never_nan_nan_) {
__ Set(eax, Immediate(0));
__ ret(0);
} else {
Label return_equal;
Label heap_number;
// If it's not a heap number, then return equal.
__ cmp(FieldOperand(edx, HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
__ j(equal, &heap_number);
__ bind(&return_equal);
__ Set(eax, Immediate(0));
__ ret(0);
__ bind(&heap_number);
// It is a heap number, so return non-equal if it's NaN and equal if
// it's not NaN.
// The representation of NaN values has all exponent bits (52..62) set,
// and not all mantissa bits (0..51) clear.
// We only accept QNaNs, which have bit 51 set.
// Read top bits of double representation (second word of value).
// Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
// all bits in the mask are set. We only need to check the word
// that contains the exponent and high bit of the mantissa.
ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
__ mov(edx, FieldOperand(edx, HeapNumber::kExponentOffset));
__ xor_(eax, Operand(eax));
// Shift value and mask so kQuietNaNHighBitsMask applies to topmost
// bits.
__ add(edx, Operand(edx));
__ cmp(edx, kQuietNaNHighBitsMask << 1);
__ setcc(above_equal, eax);
__ ret(0);
}
__ bind(¬_identical);
}
// If we're doing a strict equality comparison, we don't have to do
// type conversion, so we generate code to do fast comparison for objects
// and oddballs. Non-smi numbers and strings still go through the usual
// slow-case code.
if (strict_) {
// If either is a Smi (we know that not both are), then they can only
// be equal if the other is a HeapNumber. If so, use the slow case.
{
Label not_smis;
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(0, Smi::FromInt(0));
__ mov(ecx, Immediate(kSmiTagMask));
__ and_(ecx, Operand(eax));
__ test(ecx, Operand(edx));
__ j(not_zero, ¬_smis);
// One operand is a smi.
// Check whether the non-smi is a heap number.
ASSERT_EQ(1, kSmiTagMask);
// ecx still holds eax & kSmiTag, which is either zero or one.
__ sub(Operand(ecx), Immediate(0x01));
__ mov(ebx, edx);
__ xor_(ebx, Operand(eax));
__ and_(ebx, Operand(ecx)); // ebx holds either 0 or eax ^ edx.
__ xor_(ebx, Operand(eax));
// if eax was smi, ebx is now edx, else eax.
// Check if the non-smi operand is a heap number.
__ cmp(FieldOperand(ebx, HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
// If heap number, handle it in the slow case.
__ j(equal, &slow);
// Return non-equal (ebx is not zero)
__ mov(eax, ebx);
__ ret(0);
__ bind(¬_smis);
}
// If either operand is a JSObject or an oddball value, then they are not
// equal since their pointers are different
// There is no test for undetectability in strict equality.
// Get the type of the first operand.
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
// If the first object is a JS object, we have done pointer comparison.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
Label first_non_object;
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &first_non_object);
// Return non-zero (eax is not zero)
Label return_not_equal;
ASSERT(kHeapObjectTag != 0);
__ bind(&return_not_equal);
__ ret(0);
__ bind(&first_non_object);
// Check for oddballs: true, false, null, undefined.
__ cmp(ecx, ODDBALL_TYPE);
__ j(equal, &return_not_equal);
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(greater_equal, &return_not_equal);
// Check for oddballs: true, false, null, undefined.
__ cmp(ecx, ODDBALL_TYPE);
__ j(equal, &return_not_equal);
// Fall through to the general case.
}
__ bind(&slow);
}
// Push arguments below the return address.
__ pop(ecx);
__ push(eax);
__ push(edx);
__ push(ecx);
// Inlined floating point compare.
// Call builtin if operands are not floating point or smi.
Label check_for_symbols;
Label unordered;
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
CpuFeatures::Scope use_cmov(CMOV);
FloatingPointHelper::LoadSSE2Operands(masm, &check_for_symbols);
__ comisd(xmm0, xmm1);
// Jump to builtin for NaN.
__ j(parity_even, &unordered, not_taken);
__ mov(eax, 0); // equal
__ mov(ecx, Immediate(Smi::FromInt(1)));
__ cmov(above, eax, Operand(ecx));
__ mov(ecx, Immediate(Smi::FromInt(-1)));
__ cmov(below, eax, Operand(ecx));
__ ret(2 * kPointerSize);
} else {
FloatingPointHelper::CheckFloatOperands(masm, &check_for_symbols, ebx);
FloatingPointHelper::LoadFloatOperands(masm, ecx);
__ FCmp();
// Jump to builtin for NaN.
__ j(parity_even, &unordered, not_taken);
Label below_lbl, above_lbl;
// Return a result of -1, 0, or 1, to indicate result of comparison.
__ j(below, &below_lbl, not_taken);
__ j(above, &above_lbl, not_taken);
__ xor_(eax, Operand(eax)); // equal
// Both arguments were pushed in case a runtime call was needed.
__ ret(2 * kPointerSize);
__ bind(&below_lbl);
__ mov(eax, Immediate(Smi::FromInt(-1)));
__ ret(2 * kPointerSize);
__ bind(&above_lbl);
__ mov(eax, Immediate(Smi::FromInt(1)));
__ ret(2 * kPointerSize); // eax, edx were pushed
}
// If one of the numbers was NaN, then the result is always false.
// The cc is never not-equal.
__ bind(&unordered);
ASSERT(cc_ != not_equal);
if (cc_ == less || cc_ == less_equal) {
__ mov(eax, Immediate(Smi::FromInt(1)));
} else {
__ mov(eax, Immediate(Smi::FromInt(-1)));
}
__ ret(2 * kPointerSize); // eax, edx were pushed
// Fast negative check for symbol-to-symbol equality.
__ bind(&check_for_symbols);
Label check_for_strings;
if (cc_ == equal) {
BranchIfNonSymbol(masm, &check_for_strings, eax, ecx);
BranchIfNonSymbol(masm, &check_for_strings, edx, ecx);
// We've already checked for object identity, so if both operands
// are symbols they aren't equal. Register eax already holds a
// non-zero value, which indicates not equal, so just return.
__ ret(2 * kPointerSize);
}
__ bind(&check_for_strings);
__ JumpIfNotBothSequentialAsciiStrings(edx, eax, ecx, ebx, &call_builtin);
// Inline comparison of ascii strings.
StringCompareStub::GenerateCompareFlatAsciiStrings(masm,
edx,
eax,
ecx,
ebx,
edi);
#ifdef DEBUG
__ Abort("Unexpected fall-through from string comparison");
#endif
__ bind(&call_builtin);
// must swap argument order
__ pop(ecx);
__ pop(edx);
__ pop(eax);
__ push(edx);
__ push(eax);
// Figure out which native to call and setup the arguments.
Builtins::JavaScript builtin;
if (cc_ == equal) {
builtin = strict_ ? Builtins::STRICT_EQUALS : Builtins::EQUALS;
} else {
builtin = Builtins::COMPARE;
int ncr; // NaN compare result
if (cc_ == less || cc_ == less_equal) {
ncr = GREATER;
} else {
ASSERT(cc_ == greater || cc_ == greater_equal); // remaining cases
ncr = LESS;
}
__ push(Immediate(Smi::FromInt(ncr)));
}
// Restore return address on the stack.
__ push(ecx);
// Call the native; it returns -1 (less), 0 (equal), or 1 (greater)
// tagged as a small integer.
__ InvokeBuiltin(builtin, JUMP_FUNCTION);
}
void CompareStub::BranchIfNonSymbol(MacroAssembler* masm,
Label* label,
Register object,
Register scratch) {
__ test(object, Immediate(kSmiTagMask));
__ j(zero, label);
__ mov(scratch, FieldOperand(object, HeapObject::kMapOffset));
__ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
__ and_(scratch, kIsSymbolMask | kIsNotStringMask);
__ cmp(scratch, kSymbolTag | kStringTag);
__ j(not_equal, label);
}
void StackCheckStub::Generate(MacroAssembler* masm) {
// Because builtins always remove the receiver from the stack, we
// have to fake one to avoid underflowing the stack. The receiver
// must be inserted below the return address on the stack so we
// temporarily store that in a register.
__ pop(eax);
__ push(Immediate(Smi::FromInt(0)));
__ push(eax);
// Do tail-call to runtime routine.
__ TailCallRuntime(ExternalReference(Runtime::kStackGuard), 1, 1);
}
void CallFunctionStub::Generate(MacroAssembler* masm) {
Label slow;
// If the receiver might be a value (string, number or boolean) check for this
// and box it if it is.
if (ReceiverMightBeValue()) {
// Get the receiver from the stack.
// +1 ~ return address
Label receiver_is_value, receiver_is_js_object;
__ mov(eax, Operand(esp, (argc_ + 1) * kPointerSize));
// Check if receiver is a smi (which is a number value).
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &receiver_is_value, not_taken);
// Check if the receiver is a valid JS object.
__ CmpObjectType(eax, FIRST_JS_OBJECT_TYPE, edi);
__ j(above_equal, &receiver_is_js_object);
// Call the runtime to box the value.
__ bind(&receiver_is_value);
__ EnterInternalFrame();
__ push(eax);
__ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
__ LeaveInternalFrame();
__ mov(Operand(esp, (argc_ + 1) * kPointerSize), eax);
__ bind(&receiver_is_js_object);
}
// Get the function to call from the stack.
// +2 ~ receiver, return address
__ mov(edi, Operand(esp, (argc_ + 2) * kPointerSize));
// Check that the function really is a JavaScript function.
__ test(edi, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
// Goto slow case if we do not have a function.
__ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
__ j(not_equal, &slow, not_taken);
// Fast-case: Just invoke the function.
ParameterCount actual(argc_);
__ InvokeFunction(edi, actual, JUMP_FUNCTION);
// Slow-case: Non-function called.
__ bind(&slow);
// CALL_NON_FUNCTION expects the non-function callee as receiver (instead
// of the original receiver from the call site).
__ mov(Operand(esp, (argc_ + 1) * kPointerSize), edi);
__ Set(eax, Immediate(argc_));
__ Set(ebx, Immediate(0));
__ GetBuiltinEntry(edx, Builtins::CALL_NON_FUNCTION);
Handle<Code> adaptor(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline));
__ jmp(adaptor, RelocInfo::CODE_TARGET);
}
void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
// eax holds the exception.
// Adjust this code if not the case.
ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop the sp to the top of the handler.
ExternalReference handler_address(Top::k_handler_address);
__ mov(esp, Operand::StaticVariable(handler_address));
// Restore next handler and frame pointer, discard handler state.
ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(Operand::StaticVariable(handler_address));
ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
__ pop(ebp);
__ pop(edx); // Remove state.
// Before returning we restore the context from the frame pointer if
// not NULL. The frame pointer is NULL in the exception handler of
// a JS entry frame.
__ xor_(esi, Operand(esi)); // Tentatively set context pointer to NULL.
Label skip;
__ cmp(ebp, 0);
__ j(equal, &skip, not_taken);
__ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
__ bind(&skip);
ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ ret(0);
}
// If true, a Handle<T> passed by value is passed and returned by
// using the location_ field directly. If false, it is passed and
// returned as a pointer to a handle.
#ifdef USING_MAC_ABI
static const bool kPassHandlesDirectly = true;
#else
static const bool kPassHandlesDirectly = false;
#endif
void ApiGetterEntryStub::Generate(MacroAssembler* masm) {
Label get_result;
Label prologue;
Label promote_scheduled_exception;
__ EnterApiExitFrame(ExitFrame::MODE_NORMAL, kStackSpace, kArgc);
ASSERT_EQ(kArgc, 4);
if (kPassHandlesDirectly) {
// When handles as passed directly we don't have to allocate extra
// space for and pass an out parameter.
__ mov(Operand(esp, 0 * kPointerSize), ebx); // name.
__ mov(Operand(esp, 1 * kPointerSize), eax); // arguments pointer.
} else {
// The function expects three arguments to be passed but we allocate
// four to get space for the output cell. The argument slots are filled
// as follows:
//
// 3: output cell
// 2: arguments pointer
// 1: name
// 0: pointer to the output cell
//
// Note that this is one more "argument" than the function expects
// so the out cell will have to be popped explicitly after returning
// from the function.
__ mov(Operand(esp, 1 * kPointerSize), ebx); // name.
__ mov(Operand(esp, 2 * kPointerSize), eax); // arguments pointer.
__ mov(ebx, esp);
__ add(Operand(ebx), Immediate(3 * kPointerSize));
__ mov(Operand(esp, 0 * kPointerSize), ebx); // output
__ mov(Operand(esp, 3 * kPointerSize), Immediate(0)); // out cell.
}
// Call the api function!
__ call(fun()->address(), RelocInfo::RUNTIME_ENTRY);
// Check if the function scheduled an exception.
ExternalReference scheduled_exception_address =
ExternalReference::scheduled_exception_address();
__ cmp(Operand::StaticVariable(scheduled_exception_address),
Immediate(Factory::the_hole_value()));
__ j(not_equal, &promote_scheduled_exception, not_taken);
if (!kPassHandlesDirectly) {
// The returned value is a pointer to the handle holding the result.
// Dereference this to get to the location.
__ mov(eax, Operand(eax, 0));
}
// Check if the result handle holds 0
__ test(eax, Operand(eax));
__ j(not_zero, &get_result, taken);
// It was zero; the result is undefined.
__ mov(eax, Factory::undefined_value());
__ jmp(&prologue);
// It was non-zero. Dereference to get the result value.
__ bind(&get_result);
__ mov(eax, Operand(eax, 0));
__ bind(&prologue);
__ LeaveExitFrame(ExitFrame::MODE_NORMAL);
__ ret(0);
__ bind(&promote_scheduled_exception);
__ TailCallRuntime(ExternalReference(Runtime::kPromoteScheduledException),
0,
1);
}
void CEntryStub::GenerateCore(MacroAssembler* masm,
Label* throw_normal_exception,
Label* throw_termination_exception,
Label* throw_out_of_memory_exception,
bool do_gc,
bool always_allocate_scope) {
// eax: result parameter for PerformGC, if any
// ebx: pointer to C function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// edi: number of arguments including receiver (C callee-saved)
// esi: pointer to the first argument (C callee-saved)
// Result returned in eax, or eax+edx if result_size_ is 2.
if (do_gc) {
__ mov(Operand(esp, 0 * kPointerSize), eax); // Result.
__ call(FUNCTION_ADDR(Runtime::PerformGC), RelocInfo::RUNTIME_ENTRY);
}
ExternalReference scope_depth =
ExternalReference::heap_always_allocate_scope_depth();
if (always_allocate_scope) {
__ inc(Operand::StaticVariable(scope_depth));
}
// Call C function.
__ mov(Operand(esp, 0 * kPointerSize), edi); // argc.
__ mov(Operand(esp, 1 * kPointerSize), esi); // argv.
__ call(Operand(ebx));
// Result is in eax or edx:eax - do not destroy these registers!
if (always_allocate_scope) {
__ dec(Operand::StaticVariable(scope_depth));
}
// Make sure we're not trying to return 'the hole' from the runtime
// call as this may lead to crashes in the IC code later.
if (FLAG_debug_code) {
Label okay;
__ cmp(eax, Factory::the_hole_value());
__ j(not_equal, &okay);
__ int3();
__ bind(&okay);
}
// Check for failure result.
Label failure_returned;
ASSERT(((kFailureTag + 1) & kFailureTagMask) == 0);
__ lea(ecx, Operand(eax, 1));
// Lower 2 bits of ecx are 0 iff eax has failure tag.
__ test(ecx, Immediate(kFailureTagMask));
__ j(zero, &failure_returned, not_taken);
// Exit the JavaScript to C++ exit frame.
__ LeaveExitFrame(mode_);
__ ret(0);
// Handling of failure.
__ bind(&failure_returned);
Label retry;
// If the returned exception is RETRY_AFTER_GC continue at retry label
ASSERT(Failure::RETRY_AFTER_GC == 0);
__ test(eax, Immediate(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize));
__ j(zero, &retry, taken);
// Special handling of out of memory exceptions.
__ cmp(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
__ j(equal, throw_out_of_memory_exception);
// Retrieve the pending exception and clear the variable.
ExternalReference pending_exception_address(Top::k_pending_exception_address);
__ mov(eax, Operand::StaticVariable(pending_exception_address));
__ mov(edx,
Operand::StaticVariable(ExternalReference::the_hole_value_location()));
__ mov(Operand::StaticVariable(pending_exception_address), edx);
// Special handling of termination exceptions which are uncatchable
// by javascript code.
__ cmp(eax, Factory::termination_exception());
__ j(equal, throw_termination_exception);
// Handle normal exception.
__ jmp(throw_normal_exception);
// Retry.
__ bind(&retry);
}
void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm,
UncatchableExceptionType type) {
// Adjust this code if not the case.
ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop sp to the top stack handler.
ExternalReference handler_address(Top::k_handler_address);
__ mov(esp, Operand::StaticVariable(handler_address));
// Unwind the handlers until the ENTRY handler is found.
Label loop, done;
__ bind(&loop);
// Load the type of the current stack handler.
const int kStateOffset = StackHandlerConstants::kStateOffset;
__ cmp(Operand(esp, kStateOffset), Immediate(StackHandler::ENTRY));
__ j(equal, &done);
// Fetch the next handler in the list.
const int kNextOffset = StackHandlerConstants::kNextOffset;
__ mov(esp, Operand(esp, kNextOffset));
__ jmp(&loop);
__ bind(&done);
// Set the top handler address to next handler past the current ENTRY handler.
ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(Operand::StaticVariable(handler_address));
if (type == OUT_OF_MEMORY) {
// Set external caught exception to false.
ExternalReference external_caught(Top::k_external_caught_exception_address);
__ mov(eax, false);
__ mov(Operand::StaticVariable(external_caught), eax);
// Set pending exception and eax to out of memory exception.
ExternalReference pending_exception(Top::k_pending_exception_address);
__ mov(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
__ mov(Operand::StaticVariable(pending_exception), eax);
}
// Clear the context pointer.
__ xor_(esi, Operand(esi));
// Restore fp from handler and discard handler state.
ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
__ pop(ebp);
__ pop(edx); // State.
ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ ret(0);
}
void CEntryStub::Generate(MacroAssembler* masm) {
// eax: number of arguments including receiver
// ebx: pointer to C function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// esi: current context (C callee-saved)
// edi: JS function of the caller (C callee-saved)
// NOTE: Invocations of builtins may return failure objects instead
// of a proper result. The builtin entry handles this by performing
// a garbage collection and retrying the builtin (twice).
// Enter the exit frame that transitions from JavaScript to C++.
__ EnterExitFrame(mode_);
// eax: result parameter for PerformGC, if any (setup below)
// ebx: pointer to builtin function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// edi: number of arguments including receiver (C callee-saved)
// esi: argv pointer (C callee-saved)
Label throw_normal_exception;
Label throw_termination_exception;
Label throw_out_of_memory_exception;
// Call into the runtime system.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
false,
false);
// Do space-specific GC and retry runtime call.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
true,
false);
// Do full GC and retry runtime call one final time.
Failure* failure = Failure::InternalError();
__ mov(eax, Immediate(reinterpret_cast<int32_t>(failure)));
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
true,
true);
__ bind(&throw_out_of_memory_exception);
GenerateThrowUncatchable(masm, OUT_OF_MEMORY);
__ bind(&throw_termination_exception);
GenerateThrowUncatchable(masm, TERMINATION);
__ bind(&throw_normal_exception);
GenerateThrowTOS(masm);
}
void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
Label invoke, exit;
#ifdef ENABLE_LOGGING_AND_PROFILING
Label not_outermost_js, not_outermost_js_2;
#endif
// Setup frame.
__ push(ebp);
__ mov(ebp, Operand(esp));
// Push marker in two places.
int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
__ push(Immediate(Smi::FromInt(marker))); // context slot
__ push(Immediate(Smi::FromInt(marker))); // function slot
// Save callee-saved registers (C calling conventions).
__ push(edi);
__ push(esi);
__ push(ebx);
// Save copies of the top frame descriptor on the stack.
ExternalReference c_entry_fp(Top::k_c_entry_fp_address);
__ push(Operand::StaticVariable(c_entry_fp));
#ifdef ENABLE_LOGGING_AND_PROFILING
// If this is the outermost JS call, set js_entry_sp value.
ExternalReference js_entry_sp(Top::k_js_entry_sp_address);
__ cmp(Operand::StaticVariable(js_entry_sp), Immediate(0));
__ j(not_equal, ¬_outermost_js);
__ mov(Operand::StaticVariable(js_entry_sp), ebp);
__ bind(¬_outermost_js);
#endif
// Call a faked try-block that does the invoke.
__ call(&invoke);
// Caught exception: Store result (exception) in the pending
// exception field in the JSEnv and return a failure sentinel.
ExternalReference pending_exception(Top::k_pending_exception_address);
__ mov(Operand::StaticVariable(pending_exception), eax);
__ mov(eax, reinterpret_cast<int32_t>(Failure::Exception()));
__ jmp(&exit);
// Invoke: Link this frame into the handler chain.
__ bind(&invoke);
__ PushTryHandler(IN_JS_ENTRY, JS_ENTRY_HANDLER);
// Clear any pending exceptions.
__ mov(edx,
Operand::StaticVariable(ExternalReference::the_hole_value_location()));
__ mov(Operand::StaticVariable(pending_exception), edx);
// Fake a receiver (NULL).
__ push(Immediate(0)); // receiver
// Invoke the function by calling through JS entry trampoline
// builtin and pop the faked function when we return. Notice that we
// cannot store a reference to the trampoline code directly in this
// stub, because the builtin stubs may not have been generated yet.
if (is_construct) {
ExternalReference construct_entry(Builtins::JSConstructEntryTrampoline);
__ mov(edx, Immediate(construct_entry));
} else {
ExternalReference entry(Builtins::JSEntryTrampoline);
__ mov(edx, Immediate(entry));
}
__ mov(edx, Operand(edx, 0)); // deref address
__ lea(edx, FieldOperand(edx, Code::kHeaderSize));
__ call(Operand(edx));
// Unlink this frame from the handler chain.
__ pop(Operand::StaticVariable(ExternalReference(Top::k_handler_address)));
// Pop next_sp.
__ add(Operand(esp), Immediate(StackHandlerConstants::kSize - kPointerSize));
#ifdef ENABLE_LOGGING_AND_PROFILING
// If current EBP value is the same as js_entry_sp value, it means that
// the current function is the outermost.
__ cmp(ebp, Operand::StaticVariable(js_entry_sp));
__ j(not_equal, ¬_outermost_js_2);
__ mov(Operand::StaticVariable(js_entry_sp), Immediate(0));
__ bind(¬_outermost_js_2);
#endif
// Restore the top frame descriptor from the stack.
__ bind(&exit);
__ pop(Operand::StaticVariable(ExternalReference(Top::k_c_entry_fp_address)));
// Restore callee-saved registers (C calling conventions).
__ pop(ebx);
__ pop(esi);
__ pop(edi);
__ add(Operand(esp), Immediate(2 * kPointerSize)); // remove markers
// Restore frame pointer and return.
__ pop(ebp);
__ ret(0);
}
void InstanceofStub::Generate(MacroAssembler* masm) {
// Get the object - go slow case if it's a smi.
Label slow;
__ mov(eax, Operand(esp, 2 * kPointerSize)); // 2 ~ return address, function
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
// Check that the left hand is a JS object.
__ mov(eax, FieldOperand(eax, HeapObject::kMapOffset)); // eax - object map
__ movzx_b(ecx, FieldOperand(eax, Map::kInstanceTypeOffset)); // ecx - type
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &slow, not_taken);
__ cmp(ecx, LAST_JS_OBJECT_TYPE);
__ j(greater, &slow, not_taken);
// Get the prototype of the function.
__ mov(edx, Operand(esp, 1 * kPointerSize)); // 1 ~ return address
__ TryGetFunctionPrototype(edx, ebx, ecx, &slow);
// Check that the function prototype is a JS object.
__ test(ebx, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
__ mov(ecx, FieldOperand(ebx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &slow, not_taken);
__ cmp(ecx, LAST_JS_OBJECT_TYPE);
__ j(greater, &slow, not_taken);
// Register mapping: eax is object map and ebx is function prototype.
__ mov(ecx, FieldOperand(eax, Map::kPrototypeOffset));
// Loop through the prototype chain looking for the function prototype.
Label loop, is_instance, is_not_instance;
__ bind(&loop);
__ cmp(ecx, Operand(ebx));
__ j(equal, &is_instance);
__ cmp(Operand(ecx), Immediate(Factory::null_value()));
__ j(equal, &is_not_instance);
__ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
__ mov(ecx, FieldOperand(ecx, Map::kPrototypeOffset));
__ jmp(&loop);
__ bind(&is_instance);
__ Set(eax, Immediate(0));
__ ret(2 * kPointerSize);
__ bind(&is_not_instance);
__ Set(eax, Immediate(Smi::FromInt(1)));
__ ret(2 * kPointerSize);
// Slow-case: Go through the JavaScript implementation.
__ bind(&slow);
__ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
}
// Unfortunately you have to run without snapshots to see most of these
// names in the profile since most compare stubs end up in the snapshot.
const char* CompareStub::GetName() {
switch (cc_) {
case less: return "CompareStub_LT";
case greater: return "CompareStub_GT";
case less_equal: return "CompareStub_LE";
case greater_equal: return "CompareStub_GE";
case not_equal: {
if (strict_) {
if (never_nan_nan_) {
return "CompareStub_NE_STRICT_NO_NAN";
} else {
return "CompareStub_NE_STRICT";
}
} else {
if (never_nan_nan_) {
return "CompareStub_NE_NO_NAN";
} else {
return "CompareStub_NE";
}
}
}
case equal: {
if (strict_) {
if (never_nan_nan_) {
return "CompareStub_EQ_STRICT_NO_NAN";
} else {
return "CompareStub_EQ_STRICT";
}
} else {
if (never_nan_nan_) {
return "CompareStub_EQ_NO_NAN";
} else {
return "CompareStub_EQ";
}
}
}
default: return "CompareStub";
}
}
int CompareStub::MinorKey() {
// Encode the three parameters in a unique 16 bit value.
ASSERT(static_cast<unsigned>(cc_) < (1 << 14));
int nnn_value = (never_nan_nan_ ? 2 : 0);
if (cc_ != equal) nnn_value = 0; // Avoid duplicate stubs.
return (static_cast<unsigned>(cc_) << 2) | nnn_value | (strict_ ? 1 : 0);
}
void StringAddStub::Generate(MacroAssembler* masm) {
Label string_add_runtime;
// Load the two arguments.
__ mov(eax, Operand(esp, 2 * kPointerSize)); // First argument.
__ mov(edx, Operand(esp, 1 * kPointerSize)); // Second argument.
// Make sure that both arguments are strings if not known in advance.
if (string_check_) {
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &string_add_runtime);
__ CmpObjectType(eax, FIRST_NONSTRING_TYPE, ebx);
__ j(above_equal, &string_add_runtime);
// First argument is a a string, test second.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &string_add_runtime);
__ CmpObjectType(edx, FIRST_NONSTRING_TYPE, ebx);
__ j(above_equal, &string_add_runtime);
}
// Both arguments are strings.
// eax: first string
// edx: second string
// Check if either of the strings are empty. In that case return the other.
Label second_not_zero_length, both_not_zero_length;
__ mov(ecx, FieldOperand(edx, String::kLengthOffset));
__ test(ecx, Operand(ecx));
__ j(not_zero, &second_not_zero_length);
// Second string is empty, result is first string which is already in eax.
__ IncrementCounter(&Counters::string_add_native, 1);
__ ret(2 * kPointerSize);
__ bind(&second_not_zero_length);
__ mov(ebx, FieldOperand(eax, String::kLengthOffset));
__ test(ebx, Operand(ebx));
__ j(not_zero, &both_not_zero_length);
// First string is empty, result is second string which is in edx.
__ mov(eax, edx);
__ IncrementCounter(&Counters::string_add_native, 1);
__ ret(2 * kPointerSize);
// Both strings are non-empty.
// eax: first string
// ebx: length of first string
// ecx: length of second string
// edx: second string
// Look at the length of the result of adding the two strings.
Label string_add_flat_result, longer_than_two;
__ bind(&both_not_zero_length);
__ add(ebx, Operand(ecx));
// Use the runtime system when adding two one character strings, as it
// contains optimizations for this specific case using the symbol table.
__ cmp(ebx, 2);
__ j(not_equal, &longer_than_two);
// Check that both strings are non-external ascii strings.
__ JumpIfNotBothSequentialAsciiStrings(eax, edx, ebx, ecx,
&string_add_runtime);
// Get the two characters forming the sub string.
__ movzx_b(ebx, FieldOperand(eax, SeqAsciiString::kHeaderSize));
__ movzx_b(ecx, FieldOperand(edx, SeqAsciiString::kHeaderSize));
// Try to lookup two character string in symbol table. If it is not found
// just allocate a new one.
Label make_two_character_string, make_flat_ascii_string;
GenerateTwoCharacterSymbolTableProbe(masm, ebx, ecx, eax, edx, edi,
&make_two_character_string);
__ ret(2 * kPointerSize);
__ bind(&make_two_character_string);
__ Set(ebx, Immediate(2));
__ jmp(&make_flat_ascii_string);
__ bind(&longer_than_two);
// Check if resulting string will be flat.
__ cmp(ebx, String::kMinNonFlatLength);
__ j(below, &string_add_flat_result);
// Handle exceptionally long strings in the runtime system.
ASSERT((String::kMaxLength & 0x80000000) == 0);
__ cmp(ebx, String::kMaxLength);
__ j(above, &string_add_runtime);
// If result is not supposed to be flat allocate a cons string object. If both
// strings are ascii the result is an ascii cons string.
Label non_ascii, allocated;
__ mov(edi, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(edi, Map::kInstanceTypeOffset));
__ mov(edi, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(edi, FieldOperand(edi, Map::kInstanceTypeOffset));
__ and_(ecx, Operand(edi));
ASSERT(kStringEncodingMask == kAsciiStringTag);
__ test(ecx, Immediate(kAsciiStringTag));
__ j(zero, &non_ascii);
// Allocate an acsii cons string.
__ AllocateAsciiConsString(ecx, edi, no_reg, &string_add_runtime);
__ bind(&allocated);
// Fill the fields of the cons string.
__ mov(FieldOperand(ecx, ConsString::kLengthOffset), ebx);
__ mov(FieldOperand(ecx, ConsString::kHashFieldOffset),
Immediate(String::kEmptyHashField));
__ mov(FieldOperand(ecx, ConsString::kFirstOffset), eax);
__ mov(FieldOperand(ecx, ConsString::kSecondOffset), edx);
__ mov(eax, ecx);
__ IncrementCounter(&Counters::string_add_native, 1);
__ ret(2 * kPointerSize);
__ bind(&non_ascii);
// Allocate a two byte cons string.
__ AllocateConsString(ecx, edi, no_reg, &string_add_runtime);
__ jmp(&allocated);
// Handle creating a flat result. First check that both strings are not
// external strings.
// eax: first string
// ebx: length of resulting flat string
// edx: second string
__ bind(&string_add_flat_result);
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ and_(ecx, kStringRepresentationMask);
__ cmp(ecx, kExternalStringTag);
__ j(equal, &string_add_runtime);
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ and_(ecx, kStringRepresentationMask);
__ cmp(ecx, kExternalStringTag);
__ j(equal, &string_add_runtime);
// Now check if both strings are ascii strings.
// eax: first string
// ebx: length of resulting flat string
// edx: second string
Label non_ascii_string_add_flat_result;
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
ASSERT(kStringEncodingMask == kAsciiStringTag);
__ test(ecx, Immediate(kAsciiStringTag));
__ j(zero, &non_ascii_string_add_flat_result);
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ test(ecx, Immediate(kAsciiStringTag));
__ j(zero, &string_add_runtime);
__ bind(&make_flat_ascii_string);
// Both strings are ascii strings. As they are short they are both flat.
// ebx: length of resulting flat string
__ AllocateAsciiString(eax, ebx, ecx, edx, edi, &string_add_runtime);
// eax: result string
__ mov(ecx, eax);
// Locate first character of result.
__ add(Operand(ecx), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// Load first argument and locate first character.
__ mov(edx, Operand(esp, 2 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ add(Operand(edx), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// eax: result string
// ecx: first character of result
// edx: first char of first argument
// edi: length of first argument
GenerateCopyCharacters(masm, ecx, edx, edi, ebx, true);
// Load second argument and locate first character.
__ mov(edx, Operand(esp, 1 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ add(Operand(edx), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// eax: result string
// ecx: next character of result
// edx: first char of second argument
// edi: length of second argument
GenerateCopyCharacters(masm, ecx, edx, edi, ebx, true);
__ IncrementCounter(&Counters::string_add_native, 1);
__ ret(2 * kPointerSize);
// Handle creating a flat two byte result.
// eax: first string - known to be two byte
// ebx: length of resulting flat string
// edx: second string
__ bind(&non_ascii_string_add_flat_result);
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ and_(ecx, kAsciiStringTag);
__ j(not_zero, &string_add_runtime);
// Both strings are two byte strings. As they are short they are both
// flat.
__ AllocateTwoByteString(eax, ebx, ecx, edx, edi, &string_add_runtime);
// eax: result string
__ mov(ecx, eax);
// Locate first character of result.
__ add(Operand(ecx),
Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// Load first argument and locate first character.
__ mov(edx, Operand(esp, 2 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ add(Operand(edx),
Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// eax: result string
// ecx: first character of result
// edx: first char of first argument
// edi: length of first argument
GenerateCopyCharacters(masm, ecx, edx, edi, ebx, false);
// Load second argument and locate first character.
__ mov(edx, Operand(esp, 1 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ add(Operand(edx), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// eax: result string
// ecx: next character of result
// edx: first char of second argument
// edi: length of second argument
GenerateCopyCharacters(masm, ecx, edx, edi, ebx, false);
__ IncrementCounter(&Counters::string_add_native, 1);
__ ret(2 * kPointerSize);
// Just jump to runtime to add the two strings.
__ bind(&string_add_runtime);
__ TailCallRuntime(ExternalReference(Runtime::kStringAdd), 2, 1);
}
void StringStubBase::GenerateCopyCharacters(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch,
bool ascii) {
Label loop;
__ bind(&loop);
// This loop just copies one character at a time, as it is only used for very
// short strings.
if (ascii) {
__ mov_b(scratch, Operand(src, 0));
__ mov_b(Operand(dest, 0), scratch);
__ add(Operand(src), Immediate(1));
__ add(Operand(dest), Immediate(1));
} else {
__ mov_w(scratch, Operand(src, 0));
__ mov_w(Operand(dest, 0), scratch);
__ add(Operand(src), Immediate(2));
__ add(Operand(dest), Immediate(2));
}
__ sub(Operand(count), Immediate(1));
__ j(not_zero, &loop);
}
void StringStubBase::GenerateCopyCharactersREP(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch,
bool ascii) {
// Copy characters using rep movs of doublewords. Align destination on 4 byte
// boundary before starting rep movs. Copy remaining characters after running
// rep movs.
ASSERT(dest.is(edi)); // rep movs destination
ASSERT(src.is(esi)); // rep movs source
ASSERT(count.is(ecx)); // rep movs count
ASSERT(!scratch.is(dest));
ASSERT(!scratch.is(src));
ASSERT(!scratch.is(count));
// Nothing to do for zero characters.
Label done;
__ test(count, Operand(count));
__ j(zero, &done);
// Make count the number of bytes to copy.
if (!ascii) {
__ shl(count, 1);
}
// Don't enter the rep movs if there are less than 4 bytes to copy.
Label last_bytes;
__ test(count, Immediate(~3));
__ j(zero, &last_bytes);
// Copy from edi to esi using rep movs instruction.
__ mov(scratch, count);
__ sar(count, 2); // Number of doublewords to copy.
__ rep_movs();
// Find number of bytes left.
__ mov(count, scratch);
__ and_(count, 3);
// Check if there are more bytes to copy.
__ bind(&last_bytes);
__ test(count, Operand(count));
__ j(zero, &done);
// Copy remaining characters.
Label loop;
__ bind(&loop);
__ mov_b(scratch, Operand(src, 0));
__ mov_b(Operand(dest, 0), scratch);
__ add(Operand(src), Immediate(1));
__ add(Operand(dest), Immediate(1));
__ sub(Operand(count), Immediate(1));
__ j(not_zero, &loop);
__ bind(&done);
}
void StringStubBase::GenerateTwoCharacterSymbolTableProbe(MacroAssembler* masm,
Register c1,
Register c2,
Register scratch1,
Register scratch2,
Register scratch3,
Label* not_found) {
// Register scratch3 is the general scratch register in this function.
Register scratch = scratch3;
// Make sure that both characters are not digits as such strings has a
// different hash algorithm. Don't try to look for these in the symbol table.
Label not_array_index;
__ mov(scratch, c1);
__ sub(Operand(scratch), Immediate(static_cast<int>('0')));
__ cmp(Operand(scratch), Immediate(static_cast<int>('9' - '0')));
__ j(above, ¬_array_index);
__ mov(scratch, c2);
__ sub(Operand(scratch), Immediate(static_cast<int>('0')));
__ cmp(Operand(scratch), Immediate(static_cast<int>('9' - '0')));
__ j(below_equal, not_found);
__ bind(¬_array_index);
// Calculate the two character string hash.
Register hash = scratch1;
GenerateHashInit(masm, hash, c1, scratch);
GenerateHashAddCharacter(masm, hash, c2, scratch);
GenerateHashGetHash(masm, hash, scratch);
// Collect the two characters in a register.
Register chars = c1;
__ shl(c2, kBitsPerByte);
__ or_(chars, Operand(c2));
// chars: two character string, char 1 in byte 0 and char 2 in byte 1.
// hash: hash of two character string.
// Load the symbol table.
Register symbol_table = c2;
ExternalReference roots_address = ExternalReference::roots_address();
__ mov(scratch, Immediate(Heap::kSymbolTableRootIndex));
__ mov(symbol_table,
Operand::StaticArray(scratch, times_pointer_size, roots_address));
// Calculate capacity mask from the symbol table capacity.
Register mask = scratch2;
static const int kCapacityOffset =
FixedArray::kHeaderSize +
SymbolTable::kCapacityIndex * kPointerSize;
__ mov(mask, FieldOperand(symbol_table, kCapacityOffset));
__ SmiUntag(mask);
__ sub(Operand(mask), Immediate(1));
// Registers
// chars: two character string, char 1 in byte 0 and char 2 in byte 1.
// hash: hash of two character string
// symbol_table: symbol table
// mask: capacity mask
// scratch: -
// Perform a number of probes in the symbol table.
static const int kProbes = 4;
Label found_in_symbol_table;
Label next_probe[kProbes], next_probe_pop_mask[kProbes];
for (int i = 0; i < kProbes; i++) {
// Calculate entry in symbol table.
__ mov(scratch, hash);
if (i > 0) {
__ add(Operand(scratch), Immediate(SymbolTable::GetProbeOffset(i)));
}
__ and_(scratch, Operand(mask));
// Load the entry from the symble table.
Register candidate = scratch; // Scratch register contains candidate.
ASSERT_EQ(1, SymbolTableShape::kEntrySize);
static const int kFirstElementOffset =
FixedArray::kHeaderSize +
SymbolTable::kPrefixStartIndex * kPointerSize +
SymbolTableShape::kPrefixSize * kPointerSize;
__ mov(candidate,
FieldOperand(symbol_table,
scratch,
times_pointer_size,
kFirstElementOffset));
// If entry is undefined no string with this hash can be found.
__ cmp(candidate, Factory::undefined_value());
__ j(equal, not_found);
// If length is not 2 the string is not a candidate.
__ cmp(FieldOperand(candidate, String::kLengthOffset), Immediate(2));
__ j(not_equal, &next_probe[i]);
// As we are out of registers save the mask on the stack and use that
// register as a temporary.
__ push(mask);
Register temp = mask;
// Check that the candidate is a non-external ascii string.
__ mov(temp, FieldOperand(candidate, HeapObject::kMapOffset));
__ movzx_b(temp, FieldOperand(temp, Map::kInstanceTypeOffset));
__ JumpIfInstanceTypeIsNotSequentialAscii(
temp, temp, &next_probe_pop_mask[i]);
// Check if the two characters match.
__ mov(temp, FieldOperand(candidate, SeqAsciiString::kHeaderSize));
__ and_(temp, 0x0000ffff);
__ cmp(chars, Operand(temp));
__ j(equal, &found_in_symbol_table);
__ bind(&next_probe_pop_mask[i]);
__ pop(mask);
__ bind(&next_probe[i]);
}
// No matching 2 character string found by probing.
__ jmp(not_found);
// Scratch register contains result when we fall through to here.
Register result = scratch;
__ bind(&found_in_symbol_table);
__ pop(mask); // Pop temporally saved mask from the stack.
if (!result.is(eax)) {
__ mov(eax, result);
}
}
void StringStubBase::GenerateHashInit(MacroAssembler* masm,
Register hash,
Register character,
Register scratch) {
// hash = character + (character << 10);
__ mov(hash, character);
__ shl(hash, 10);
__ add(hash, Operand(character));
// hash ^= hash >> 6;
__ mov(scratch, hash);
__ sar(scratch, 6);
__ xor_(hash, Operand(scratch));
}
void StringStubBase::GenerateHashAddCharacter(MacroAssembler* masm,
Register hash,
Register character,
Register scratch) {
// hash += character;
__ add(hash, Operand(character));
// hash += hash << 10;
__ mov(scratch, hash);
__ shl(scratch, 10);
__ add(hash, Operand(scratch));
// hash ^= hash >> 6;
__ mov(scratch, hash);
__ sar(scratch, 6);
__ xor_(hash, Operand(scratch));
}
void StringStubBase::GenerateHashGetHash(MacroAssembler* masm,
Register hash,
Register scratch) {
// hash += hash << 3;
__ mov(scratch, hash);
__ shl(scratch, 3);
__ add(hash, Operand(scratch));
// hash ^= hash >> 11;
__ mov(scratch, hash);
__ sar(scratch, 11);
__ xor_(hash, Operand(scratch));
// hash += hash << 15;
__ mov(scratch, hash);
__ shl(scratch, 15);
__ add(hash, Operand(scratch));
// if (hash == 0) hash = 27;
Label hash_not_zero;
__ test(hash, Operand(hash));
__ j(not_zero, &hash_not_zero);
__ mov(hash, Immediate(27));
__ bind(&hash_not_zero);
}
void SubStringStub::Generate(MacroAssembler* masm) {
Label runtime;
// Stack frame on entry.
// esp[0]: return address
// esp[4]: to
// esp[8]: from
// esp[12]: string
// Make sure first argument is a string.
__ mov(eax, Operand(esp, 3 * kPointerSize));
ASSERT_EQ(0, kSmiTag);
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &runtime);
Condition is_string = masm->IsObjectStringType(eax, ebx, ebx);
__ j(NegateCondition(is_string), &runtime);
// eax: string
// ebx: instance type
// Calculate length of sub string using the smi values.
Label result_longer_than_two;
__ mov(ecx, Operand(esp, 1 * kPointerSize)); // To index.
__ test(ecx, Immediate(kSmiTagMask));
__ j(not_zero, &runtime);
__ mov(edx, Operand(esp, 2 * kPointerSize)); // From index.
__ test(edx, Immediate(kSmiTagMask));
__ j(not_zero, &runtime);
__ sub(ecx, Operand(edx));
// Special handling of sub-strings of length 1 and 2. One character strings
// are handled in the runtime system (looked up in the single character
// cache). Two character strings are looked for in the symbol cache.
__ SmiUntag(ecx); // Result length is no longer smi.
__ cmp(ecx, 2);
__ j(greater, &result_longer_than_two);
__ j(less, &runtime);
// Sub string of length 2 requested.
// eax: string
// ebx: instance type
// ecx: sub string length (value is 2)
// edx: from index (smi)
__ JumpIfInstanceTypeIsNotSequentialAscii(ebx, ebx, &runtime);
// Get the two characters forming the sub string.
__ SmiUntag(edx); // From index is no longer smi.
__ movzx_b(ebx, FieldOperand(eax, edx, times_1, SeqAsciiString::kHeaderSize));
__ movzx_b(ecx,
FieldOperand(eax, edx, times_1, SeqAsciiString::kHeaderSize + 1));
// Try to lookup two character string in symbol table.
Label make_two_character_string;
GenerateTwoCharacterSymbolTableProbe(masm, ebx, ecx, eax, edx, edi,
&make_two_character_string);
__ ret(2 * kPointerSize);
__ bind(&make_two_character_string);
// Setup registers for allocating the two character string.
__ mov(eax, Operand(esp, 3 * kPointerSize));
__ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ebx, FieldOperand(ebx, Map::kInstanceTypeOffset));
__ Set(ecx, Immediate(2));
__ bind(&result_longer_than_two);
// eax: string
// ebx: instance type
// ecx: result string length
// Check for flat ascii string
Label non_ascii_flat;
__ JumpIfInstanceTypeIsNotSequentialAscii(ebx, ebx, &non_ascii_flat);
// Allocate the result.
__ AllocateAsciiString(eax, ecx, ebx, edx, edi, &runtime);
// eax: result string
// ecx: result string length
__ mov(edx, esi); // esi used by following code.
// Locate first character of result.
__ mov(edi, eax);
__ add(Operand(edi), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// Load string argument and locate character of sub string start.
__ mov(esi, Operand(esp, 3 * kPointerSize));
__ add(Operand(esi), Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
__ mov(ebx, Operand(esp, 2 * kPointerSize)); // from
__ SmiUntag(ebx);
__ add(esi, Operand(ebx));
// eax: result string
// ecx: result length
// edx: original value of esi
// edi: first character of result
// esi: character of sub string start
GenerateCopyCharactersREP(masm, edi, esi, ecx, ebx, true);
__ mov(esi, edx); // Restore esi.
__ IncrementCounter(&Counters::sub_string_native, 1);
__ ret(3 * kPointerSize);
__ bind(&non_ascii_flat);
// eax: string
// ebx: instance type & kStringRepresentationMask | kStringEncodingMask
// ecx: result string length
// Check for flat two byte string
__ cmp(ebx, kSeqStringTag | kTwoByteStringTag);
__ j(not_equal, &runtime);
// Allocate the result.
__ AllocateTwoByteString(eax, ecx, ebx, edx, edi, &runtime);
// eax: result string
// ecx: result string length
__ mov(edx, esi); // esi used by following code.
// Locate first character of result.
__ mov(edi, eax);
__ add(Operand(edi),
Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// Load string argument and locate character of sub string start.
__ mov(esi, Operand(esp, 3 * kPointerSize));
__ add(Operand(esi),
Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
__ mov(ebx, Operand(esp, 2 * kPointerSize)); // from
// As from is a smi it is 2 times the value which matches the size of a two
// byte character.
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(1, kSmiTagSize + kSmiShiftSize);
__ add(esi, Operand(ebx));
// eax: result string
// ecx: result length
// edx: original value of esi
// edi: first character of result
// esi: character of sub string start
GenerateCopyCharactersREP(masm, edi, esi, ecx, ebx, false);
__ mov(esi, edx); // Restore esi.
__ IncrementCounter(&Counters::sub_string_native, 1);
__ ret(3 * kPointerSize);
// Just jump to runtime to create the sub string.
__ bind(&runtime);
__ TailCallRuntime(ExternalReference(Runtime::kSubString), 3, 1);
}
void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm,
Register left,
Register right,
Register scratch1,
Register scratch2,
Register scratch3) {
Label result_not_equal;
Label result_greater;
Label compare_lengths;
// Find minimum length.
Label left_shorter;
__ mov(scratch1, FieldOperand(left, String::kLengthOffset));
__ mov(scratch3, scratch1);
__ sub(scratch3, FieldOperand(right, String::kLengthOffset));
Register length_delta = scratch3;
__ j(less_equal, &left_shorter);
// Right string is shorter. Change scratch1 to be length of right string.
__ sub(scratch1, Operand(length_delta));
__ bind(&left_shorter);
Register min_length = scratch1;
// If either length is zero, just compare lengths.
__ test(min_length, Operand(min_length));
__ j(zero, &compare_lengths);
// Change index to run from -min_length to -1 by adding min_length
// to string start. This means that loop ends when index reaches zero,
// which doesn't need an additional compare.
__ lea(left,
FieldOperand(left,
min_length, times_1,
SeqAsciiString::kHeaderSize));
__ lea(right,
FieldOperand(right,
min_length, times_1,
SeqAsciiString::kHeaderSize));
__ neg(min_length);
Register index = min_length; // index = -min_length;
{
// Compare loop.
Label loop;
__ bind(&loop);
// Compare characters.
__ mov_b(scratch2, Operand(left, index, times_1, 0));
__ cmpb(scratch2, Operand(right, index, times_1, 0));
__ j(not_equal, &result_not_equal);
__ add(Operand(index), Immediate(1));
__ j(not_zero, &loop);
}
// Compare lengths - strings up to min-length are equal.
__ bind(&compare_lengths);
__ test(length_delta, Operand(length_delta));
__ j(not_zero, &result_not_equal);
// Result is EQUAL.
ASSERT_EQ(0, EQUAL);
ASSERT_EQ(0, kSmiTag);
__ Set(eax, Immediate(Smi::FromInt(EQUAL)));
__ ret(2 * kPointerSize);
__ bind(&result_not_equal);
__ j(greater, &result_greater);
// Result is LESS.
__ Set(eax, Immediate(Smi::FromInt(LESS)));
__ ret(2 * kPointerSize);
// Result is GREATER.
__ bind(&result_greater);
__ Set(eax, Immediate(Smi::FromInt(GREATER)));
__ ret(2 * kPointerSize);
}
void StringCompareStub::Generate(MacroAssembler* masm) {
Label runtime;
// Stack frame on entry.
// esp[0]: return address
// esp[4]: right string
// esp[8]: left string
__ mov(edx, Operand(esp, 2 * kPointerSize)); // left
__ mov(eax, Operand(esp, 1 * kPointerSize)); // right
Label not_same;
__ cmp(edx, Operand(eax));
__ j(not_equal, ¬_same);
ASSERT_EQ(0, EQUAL);
ASSERT_EQ(0, kSmiTag);
__ Set(eax, Immediate(Smi::FromInt(EQUAL)));
__ IncrementCounter(&Counters::string_compare_native, 1);
__ ret(2 * kPointerSize);
__ bind(¬_same);
// Check that both objects are sequential ascii strings.
__ JumpIfNotBothSequentialAsciiStrings(edx, eax, ecx, ebx, &runtime);
// Compare flat ascii strings.
__ IncrementCounter(&Counters::string_compare_native, 1);
GenerateCompareFlatAsciiStrings(masm, edx, eax, ecx, ebx, edi);
// Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)
// tagged as a small integer.
__ bind(&runtime);
__ TailCallRuntime(ExternalReference(Runtime::kStringCompare), 2, 1);
}
#undef __
} } // namespace v8::internal