mirrored from https://chromium.googlesource.com/v8/v8.git
/
full-codegen-x87.cc
3640 lines (3128 loc) · 124 KB
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full-codegen-x87.cc
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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if V8_TARGET_ARCH_X87
#include "src/full-codegen/full-codegen.h"
#include "src/ast/compile-time-value.h"
#include "src/ast/scopes.h"
#include "src/code-factory.h"
#include "src/code-stubs.h"
#include "src/codegen.h"
#include "src/compilation-info.h"
#include "src/compiler.h"
#include "src/debug/debug.h"
#include "src/ic/ic.h"
#include "src/x87/frames-x87.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm())
class JumpPatchSite BASE_EMBEDDED {
public:
explicit JumpPatchSite(MacroAssembler* masm) : masm_(masm) {
#ifdef DEBUG
info_emitted_ = false;
#endif
}
~JumpPatchSite() {
DCHECK(patch_site_.is_bound() == info_emitted_);
}
void EmitJumpIfNotSmi(Register reg,
Label* target,
Label::Distance distance = Label::kFar) {
__ test(reg, Immediate(kSmiTagMask));
EmitJump(not_carry, target, distance); // Always taken before patched.
}
void EmitJumpIfSmi(Register reg,
Label* target,
Label::Distance distance = Label::kFar) {
__ test(reg, Immediate(kSmiTagMask));
EmitJump(carry, target, distance); // Never taken before patched.
}
void EmitPatchInfo() {
if (patch_site_.is_bound()) {
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(&patch_site_);
DCHECK(is_uint8(delta_to_patch_site));
__ test(eax, Immediate(delta_to_patch_site));
#ifdef DEBUG
info_emitted_ = true;
#endif
} else {
__ nop(); // Signals no inlined code.
}
}
private:
// jc will be patched with jz, jnc will become jnz.
void EmitJump(Condition cc, Label* target, Label::Distance distance) {
DCHECK(!patch_site_.is_bound() && !info_emitted_);
DCHECK(cc == carry || cc == not_carry);
__ bind(&patch_site_);
__ j(cc, target, distance);
}
MacroAssembler* masm() { return masm_; }
MacroAssembler* masm_;
Label patch_site_;
#ifdef DEBUG
bool info_emitted_;
#endif
};
// Generate code for a JS function. On entry to the function the receiver
// and arguments have been pushed on the stack left to right, with the
// return address on top of them. The actual argument count matches the
// formal parameter count expected by the function.
//
// The live registers are:
// o edi: the JS function object being called (i.e. ourselves)
// o edx: the new target value
// o esi: our context
// o ebp: our caller's frame pointer
// o esp: stack pointer (pointing to return address)
//
// The function builds a JS frame. Please see JavaScriptFrameConstants in
// frames-x87.h for its layout.
void FullCodeGenerator::Generate() {
CompilationInfo* info = info_;
profiling_counter_ = isolate()->factory()->NewCell(
Handle<Smi>(Smi::FromInt(FLAG_interrupt_budget), isolate()));
SetFunctionPosition(literal());
Comment cmnt(masm_, "[ function compiled by full code generator");
ProfileEntryHookStub::MaybeCallEntryHook(masm_);
if (FLAG_debug_code && info->ExpectsJSReceiverAsReceiver()) {
int receiver_offset = (info->scope()->num_parameters() + 1) * kPointerSize;
__ mov(ecx, Operand(esp, receiver_offset));
__ AssertNotSmi(ecx);
__ CmpObjectType(ecx, FIRST_JS_RECEIVER_TYPE, ecx);
__ Assert(above_equal, kSloppyFunctionExpectsJSReceiverReceiver);
}
// Open a frame scope to indicate that there is a frame on the stack. The
// MANUAL indicates that the scope shouldn't actually generate code to set up
// the frame (that is done below).
FrameScope frame_scope(masm_, StackFrame::MANUAL);
info->set_prologue_offset(masm_->pc_offset());
__ Prologue(info->GeneratePreagedPrologue());
{ Comment cmnt(masm_, "[ Allocate locals");
int locals_count = info->scope()->num_stack_slots();
// Generators allocate locals, if any, in context slots.
DCHECK(!IsGeneratorFunction(literal()->kind()) || locals_count == 0);
OperandStackDepthIncrement(locals_count);
if (locals_count == 1) {
__ push(Immediate(isolate()->factory()->undefined_value()));
} else if (locals_count > 1) {
if (locals_count >= 128) {
Label ok;
__ mov(ecx, esp);
__ sub(ecx, Immediate(locals_count * kPointerSize));
ExternalReference stack_limit =
ExternalReference::address_of_real_stack_limit(isolate());
__ cmp(ecx, Operand::StaticVariable(stack_limit));
__ j(above_equal, &ok, Label::kNear);
__ CallRuntime(Runtime::kThrowStackOverflow);
__ bind(&ok);
}
__ mov(eax, Immediate(isolate()->factory()->undefined_value()));
const int kMaxPushes = 32;
if (locals_count >= kMaxPushes) {
int loop_iterations = locals_count / kMaxPushes;
__ mov(ecx, loop_iterations);
Label loop_header;
__ bind(&loop_header);
// Do pushes.
for (int i = 0; i < kMaxPushes; i++) {
__ push(eax);
}
__ dec(ecx);
__ j(not_zero, &loop_header, Label::kNear);
}
int remaining = locals_count % kMaxPushes;
// Emit the remaining pushes.
for (int i = 0; i < remaining; i++) {
__ push(eax);
}
}
}
bool function_in_register = true;
// Possibly allocate a local context.
if (info->scope()->NeedsContext()) {
Comment cmnt(masm_, "[ Allocate context");
bool need_write_barrier = true;
int slots = info->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
// Argument to NewContext is the function, which is still in edi.
if (info->scope()->is_script_scope()) {
__ push(edi);
__ Push(info->scope()->scope_info());
__ CallRuntime(Runtime::kNewScriptContext);
PrepareForBailoutForId(BailoutId::ScriptContext(),
BailoutState::TOS_REGISTER);
// The new target value is not used, clobbering is safe.
DCHECK_NULL(info->scope()->new_target_var());
} else {
if (info->scope()->new_target_var() != nullptr) {
__ push(edx); // Preserve new target.
}
FastNewFunctionContextStub stub(isolate());
__ mov(FastNewFunctionContextDescriptor::SlotsRegister(),
Immediate(slots));
__ CallStub(&stub);
// Result of FastNewFunctionContextStub is always in new space.
need_write_barrier = false;
if (info->scope()->new_target_var() != nullptr) {
__ pop(edx); // Restore new target.
}
}
function_in_register = false;
// Context is returned in eax. It replaces the context passed to us.
// It's saved in the stack and kept live in esi.
__ mov(esi, eax);
__ mov(Operand(ebp, StandardFrameConstants::kContextOffset), eax);
// Copy parameters into context if necessary.
int num_parameters = info->scope()->num_parameters();
int first_parameter = info->scope()->has_this_declaration() ? -1 : 0;
for (int i = first_parameter; i < num_parameters; i++) {
Variable* var =
(i == -1) ? info->scope()->receiver() : info->scope()->parameter(i);
if (var->IsContextSlot()) {
int parameter_offset = StandardFrameConstants::kCallerSPOffset +
(num_parameters - 1 - i) * kPointerSize;
// Load parameter from stack.
__ mov(eax, Operand(ebp, parameter_offset));
// Store it in the context.
int context_offset = Context::SlotOffset(var->index());
__ mov(Operand(esi, context_offset), eax);
// Update the write barrier. This clobbers eax and ebx.
if (need_write_barrier) {
__ RecordWriteContextSlot(esi, context_offset, eax, ebx,
kDontSaveFPRegs);
} else if (FLAG_debug_code) {
Label done;
__ JumpIfInNewSpace(esi, eax, &done, Label::kNear);
__ Abort(kExpectedNewSpaceObject);
__ bind(&done);
}
}
}
}
// Register holding this function and new target are both trashed in case we
// bailout here. But since that can happen only when new target is not used
// and we allocate a context, the value of |function_in_register| is correct.
PrepareForBailoutForId(BailoutId::FunctionContext(),
BailoutState::NO_REGISTERS);
// Possibly set up a local binding to the this function which is used in
// derived constructors with super calls.
Variable* this_function_var = info->scope()->this_function_var();
if (this_function_var != nullptr) {
Comment cmnt(masm_, "[ This function");
if (!function_in_register) {
__ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
// The write barrier clobbers register again, keep it marked as such.
}
SetVar(this_function_var, edi, ebx, ecx);
}
// Possibly set up a local binding to the new target value.
Variable* new_target_var = info->scope()->new_target_var();
if (new_target_var != nullptr) {
Comment cmnt(masm_, "[ new.target");
SetVar(new_target_var, edx, ebx, ecx);
}
// Possibly allocate RestParameters
Variable* rest_param = info->scope()->rest_parameter();
if (rest_param != nullptr) {
Comment cmnt(masm_, "[ Allocate rest parameter array");
if (!function_in_register) {
__ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
}
FastNewRestParameterStub stub(isolate());
__ CallStub(&stub);
function_in_register = false;
SetVar(rest_param, eax, ebx, edx);
}
Variable* arguments = info->scope()->arguments();
if (arguments != NULL) {
// Arguments object must be allocated after the context object, in
// case the "arguments" or ".arguments" variables are in the context.
Comment cmnt(masm_, "[ Allocate arguments object");
if (!function_in_register) {
__ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
}
if (is_strict(language_mode()) || !has_simple_parameters()) {
FastNewStrictArgumentsStub stub(isolate());
__ CallStub(&stub);
} else if (literal()->has_duplicate_parameters()) {
__ Push(edi);
__ CallRuntime(Runtime::kNewSloppyArguments_Generic);
} else {
FastNewSloppyArgumentsStub stub(isolate());
__ CallStub(&stub);
}
SetVar(arguments, eax, ebx, edx);
}
if (FLAG_trace) {
__ CallRuntime(Runtime::kTraceEnter);
}
// Visit the declarations and body.
PrepareForBailoutForId(BailoutId::FunctionEntry(),
BailoutState::NO_REGISTERS);
{
Comment cmnt(masm_, "[ Declarations");
VisitDeclarations(scope()->declarations());
}
// Assert that the declarations do not use ICs. Otherwise the debugger
// won't be able to redirect a PC at an IC to the correct IC in newly
// recompiled code.
DCHECK_EQ(0, ic_total_count_);
{
Comment cmnt(masm_, "[ Stack check");
PrepareForBailoutForId(BailoutId::Declarations(),
BailoutState::NO_REGISTERS);
Label ok;
ExternalReference stack_limit =
ExternalReference::address_of_stack_limit(isolate());
__ cmp(esp, Operand::StaticVariable(stack_limit));
__ j(above_equal, &ok, Label::kNear);
__ call(isolate()->builtins()->StackCheck(), RelocInfo::CODE_TARGET);
__ bind(&ok);
}
{
Comment cmnt(masm_, "[ Body");
DCHECK(loop_depth() == 0);
VisitStatements(literal()->body());
DCHECK(loop_depth() == 0);
}
// Always emit a 'return undefined' in case control fell off the end of
// the body.
{ Comment cmnt(masm_, "[ return <undefined>;");
__ mov(eax, isolate()->factory()->undefined_value());
EmitReturnSequence();
}
}
void FullCodeGenerator::ClearAccumulator() {
__ Move(eax, Immediate(Smi::FromInt(0)));
}
void FullCodeGenerator::EmitProfilingCounterDecrement(int delta) {
__ mov(ebx, Immediate(profiling_counter_));
__ sub(FieldOperand(ebx, Cell::kValueOffset),
Immediate(Smi::FromInt(delta)));
}
void FullCodeGenerator::EmitProfilingCounterReset() {
int reset_value = FLAG_interrupt_budget;
__ mov(ebx, Immediate(profiling_counter_));
__ mov(FieldOperand(ebx, Cell::kValueOffset),
Immediate(Smi::FromInt(reset_value)));
}
void FullCodeGenerator::EmitBackEdgeBookkeeping(IterationStatement* stmt,
Label* back_edge_target) {
Comment cmnt(masm_, "[ Back edge bookkeeping");
Label ok;
DCHECK(back_edge_target->is_bound());
int distance = masm_->SizeOfCodeGeneratedSince(back_edge_target);
int weight = Min(kMaxBackEdgeWeight,
Max(1, distance / kCodeSizeMultiplier));
EmitProfilingCounterDecrement(weight);
__ j(positive, &ok, Label::kNear);
__ call(isolate()->builtins()->InterruptCheck(), RelocInfo::CODE_TARGET);
// Record a mapping of this PC offset to the OSR id. This is used to find
// the AST id from the unoptimized code in order to use it as a key into
// the deoptimization input data found in the optimized code.
RecordBackEdge(stmt->OsrEntryId());
EmitProfilingCounterReset();
__ bind(&ok);
PrepareForBailoutForId(stmt->EntryId(), BailoutState::NO_REGISTERS);
// Record a mapping of the OSR id to this PC. This is used if the OSR
// entry becomes the target of a bailout. We don't expect it to be, but
// we want it to work if it is.
PrepareForBailoutForId(stmt->OsrEntryId(), BailoutState::NO_REGISTERS);
}
void FullCodeGenerator::EmitProfilingCounterHandlingForReturnSequence(
bool is_tail_call) {
// Pretend that the exit is a backwards jump to the entry.
int weight = 1;
if (info_->ShouldSelfOptimize()) {
weight = FLAG_interrupt_budget / FLAG_self_opt_count;
} else {
int distance = masm_->pc_offset();
weight = Min(kMaxBackEdgeWeight, Max(1, distance / kCodeSizeMultiplier));
}
EmitProfilingCounterDecrement(weight);
Label ok;
__ j(positive, &ok, Label::kNear);
// Don't need to save result register if we are going to do a tail call.
if (!is_tail_call) {
__ push(eax);
}
__ call(isolate()->builtins()->InterruptCheck(), RelocInfo::CODE_TARGET);
if (!is_tail_call) {
__ pop(eax);
}
EmitProfilingCounterReset();
__ bind(&ok);
}
void FullCodeGenerator::EmitReturnSequence() {
Comment cmnt(masm_, "[ Return sequence");
if (return_label_.is_bound()) {
__ jmp(&return_label_);
} else {
// Common return label
__ bind(&return_label_);
if (FLAG_trace) {
__ push(eax);
__ CallRuntime(Runtime::kTraceExit);
}
EmitProfilingCounterHandlingForReturnSequence(false);
SetReturnPosition(literal());
__ leave();
int arg_count = info_->scope()->num_parameters() + 1;
int arguments_bytes = arg_count * kPointerSize;
__ Ret(arguments_bytes, ecx);
}
}
void FullCodeGenerator::RestoreContext() {
__ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
}
void FullCodeGenerator::StackValueContext::Plug(Variable* var) const {
DCHECK(var->IsStackAllocated() || var->IsContextSlot());
MemOperand operand = codegen()->VarOperand(var, result_register());
// Memory operands can be pushed directly.
codegen()->PushOperand(operand);
}
void FullCodeGenerator::EffectContext::Plug(Heap::RootListIndex index) const {
UNREACHABLE(); // Not used on X87.
}
void FullCodeGenerator::AccumulatorValueContext::Plug(
Heap::RootListIndex index) const {
UNREACHABLE(); // Not used on X87.
}
void FullCodeGenerator::StackValueContext::Plug(
Heap::RootListIndex index) const {
UNREACHABLE(); // Not used on X87.
}
void FullCodeGenerator::TestContext::Plug(Heap::RootListIndex index) const {
UNREACHABLE(); // Not used on X87.
}
void FullCodeGenerator::EffectContext::Plug(Handle<Object> lit) const {
}
void FullCodeGenerator::AccumulatorValueContext::Plug(
Handle<Object> lit) const {
if (lit->IsSmi()) {
__ SafeMove(result_register(), Immediate(lit));
} else {
__ Move(result_register(), Immediate(lit));
}
}
void FullCodeGenerator::StackValueContext::Plug(Handle<Object> lit) const {
codegen()->OperandStackDepthIncrement(1);
if (lit->IsSmi()) {
__ SafePush(Immediate(lit));
} else {
__ push(Immediate(lit));
}
}
void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
codegen()->PrepareForBailoutBeforeSplit(condition(),
true,
true_label_,
false_label_);
DCHECK(lit->IsNull(isolate()) || lit->IsUndefined(isolate()) ||
!lit->IsUndetectable());
if (lit->IsUndefined(isolate()) || lit->IsNull(isolate()) ||
lit->IsFalse(isolate())) {
if (false_label_ != fall_through_) __ jmp(false_label_);
} else if (lit->IsTrue(isolate()) || lit->IsJSObject()) {
if (true_label_ != fall_through_) __ jmp(true_label_);
} else if (lit->IsString()) {
if (String::cast(*lit)->length() == 0) {
if (false_label_ != fall_through_) __ jmp(false_label_);
} else {
if (true_label_ != fall_through_) __ jmp(true_label_);
}
} else if (lit->IsSmi()) {
if (Smi::cast(*lit)->value() == 0) {
if (false_label_ != fall_through_) __ jmp(false_label_);
} else {
if (true_label_ != fall_through_) __ jmp(true_label_);
}
} else {
// For simplicity we always test the accumulator register.
__ mov(result_register(), lit);
codegen()->DoTest(this);
}
}
void FullCodeGenerator::StackValueContext::DropAndPlug(int count,
Register reg) const {
DCHECK(count > 0);
if (count > 1) codegen()->DropOperands(count - 1);
__ mov(Operand(esp, 0), reg);
}
void FullCodeGenerator::EffectContext::Plug(Label* materialize_true,
Label* materialize_false) const {
DCHECK(materialize_true == materialize_false);
__ bind(materialize_true);
}
void FullCodeGenerator::AccumulatorValueContext::Plug(
Label* materialize_true,
Label* materialize_false) const {
Label done;
__ bind(materialize_true);
__ mov(result_register(), isolate()->factory()->true_value());
__ jmp(&done, Label::kNear);
__ bind(materialize_false);
__ mov(result_register(), isolate()->factory()->false_value());
__ bind(&done);
}
void FullCodeGenerator::StackValueContext::Plug(
Label* materialize_true,
Label* materialize_false) const {
codegen()->OperandStackDepthIncrement(1);
Label done;
__ bind(materialize_true);
__ push(Immediate(isolate()->factory()->true_value()));
__ jmp(&done, Label::kNear);
__ bind(materialize_false);
__ push(Immediate(isolate()->factory()->false_value()));
__ bind(&done);
}
void FullCodeGenerator::TestContext::Plug(Label* materialize_true,
Label* materialize_false) const {
DCHECK(materialize_true == true_label_);
DCHECK(materialize_false == false_label_);
}
void FullCodeGenerator::AccumulatorValueContext::Plug(bool flag) const {
Handle<Object> value = flag
? isolate()->factory()->true_value()
: isolate()->factory()->false_value();
__ mov(result_register(), value);
}
void FullCodeGenerator::StackValueContext::Plug(bool flag) const {
codegen()->OperandStackDepthIncrement(1);
Handle<Object> value = flag
? isolate()->factory()->true_value()
: isolate()->factory()->false_value();
__ push(Immediate(value));
}
void FullCodeGenerator::TestContext::Plug(bool flag) const {
codegen()->PrepareForBailoutBeforeSplit(condition(),
true,
true_label_,
false_label_);
if (flag) {
if (true_label_ != fall_through_) __ jmp(true_label_);
} else {
if (false_label_ != fall_through_) __ jmp(false_label_);
}
}
void FullCodeGenerator::DoTest(Expression* condition,
Label* if_true,
Label* if_false,
Label* fall_through) {
Handle<Code> ic = ToBooleanICStub::GetUninitialized(isolate());
CallIC(ic, condition->test_id());
__ CompareRoot(result_register(), Heap::kTrueValueRootIndex);
Split(equal, if_true, if_false, fall_through);
}
void FullCodeGenerator::Split(Condition cc,
Label* if_true,
Label* if_false,
Label* fall_through) {
if (if_false == fall_through) {
__ j(cc, if_true);
} else if (if_true == fall_through) {
__ j(NegateCondition(cc), if_false);
} else {
__ j(cc, if_true);
__ jmp(if_false);
}
}
MemOperand FullCodeGenerator::StackOperand(Variable* var) {
DCHECK(var->IsStackAllocated());
// Offset is negative because higher indexes are at lower addresses.
int offset = -var->index() * kPointerSize;
// Adjust by a (parameter or local) base offset.
if (var->IsParameter()) {
offset += (info_->scope()->num_parameters() + 1) * kPointerSize;
} else {
offset += JavaScriptFrameConstants::kLocal0Offset;
}
return Operand(ebp, offset);
}
MemOperand FullCodeGenerator::VarOperand(Variable* var, Register scratch) {
DCHECK(var->IsContextSlot() || var->IsStackAllocated());
if (var->IsContextSlot()) {
int context_chain_length = scope()->ContextChainLength(var->scope());
__ LoadContext(scratch, context_chain_length);
return ContextOperand(scratch, var->index());
} else {
return StackOperand(var);
}
}
void FullCodeGenerator::GetVar(Register dest, Variable* var) {
DCHECK(var->IsContextSlot() || var->IsStackAllocated());
MemOperand location = VarOperand(var, dest);
__ mov(dest, location);
}
void FullCodeGenerator::SetVar(Variable* var,
Register src,
Register scratch0,
Register scratch1) {
DCHECK(var->IsContextSlot() || var->IsStackAllocated());
DCHECK(!scratch0.is(src));
DCHECK(!scratch0.is(scratch1));
DCHECK(!scratch1.is(src));
MemOperand location = VarOperand(var, scratch0);
__ mov(location, src);
// Emit the write barrier code if the location is in the heap.
if (var->IsContextSlot()) {
int offset = Context::SlotOffset(var->index());
DCHECK(!scratch0.is(esi) && !src.is(esi) && !scratch1.is(esi));
__ RecordWriteContextSlot(scratch0, offset, src, scratch1, kDontSaveFPRegs);
}
}
void FullCodeGenerator::PrepareForBailoutBeforeSplit(Expression* expr,
bool should_normalize,
Label* if_true,
Label* if_false) {
// Only prepare for bailouts before splits if we're in a test
// context. Otherwise, we let the Visit function deal with the
// preparation to avoid preparing with the same AST id twice.
if (!context()->IsTest()) return;
Label skip;
if (should_normalize) __ jmp(&skip, Label::kNear);
PrepareForBailout(expr, BailoutState::TOS_REGISTER);
if (should_normalize) {
__ cmp(eax, isolate()->factory()->true_value());
Split(equal, if_true, if_false, NULL);
__ bind(&skip);
}
}
void FullCodeGenerator::EmitDebugCheckDeclarationContext(Variable* variable) {
// The variable in the declaration always resides in the current context.
DCHECK_EQ(0, scope()->ContextChainLength(variable->scope()));
if (FLAG_debug_code) {
// Check that we're not inside a with or catch context.
__ mov(ebx, FieldOperand(esi, HeapObject::kMapOffset));
__ cmp(ebx, isolate()->factory()->with_context_map());
__ Check(not_equal, kDeclarationInWithContext);
__ cmp(ebx, isolate()->factory()->catch_context_map());
__ Check(not_equal, kDeclarationInCatchContext);
}
}
void FullCodeGenerator::VisitVariableDeclaration(
VariableDeclaration* declaration) {
VariableProxy* proxy = declaration->proxy();
Variable* variable = proxy->var();
switch (variable->location()) {
case VariableLocation::UNALLOCATED: {
DCHECK(!variable->binding_needs_init());
FeedbackVectorSlot slot = proxy->VariableFeedbackSlot();
DCHECK(!slot.IsInvalid());
globals_->Add(handle(Smi::FromInt(slot.ToInt()), isolate()), zone());
globals_->Add(isolate()->factory()->undefined_value(), zone());
break;
}
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL:
if (variable->binding_needs_init()) {
Comment cmnt(masm_, "[ VariableDeclaration");
__ mov(StackOperand(variable),
Immediate(isolate()->factory()->the_hole_value()));
}
break;
case VariableLocation::CONTEXT:
if (variable->binding_needs_init()) {
Comment cmnt(masm_, "[ VariableDeclaration");
EmitDebugCheckDeclarationContext(variable);
__ mov(ContextOperand(esi, variable->index()),
Immediate(isolate()->factory()->the_hole_value()));
// No write barrier since the hole value is in old space.
PrepareForBailoutForId(proxy->id(), BailoutState::NO_REGISTERS);
}
break;
case VariableLocation::LOOKUP: {
Comment cmnt(masm_, "[ VariableDeclaration");
DCHECK_EQ(VAR, variable->mode());
DCHECK(!variable->binding_needs_init());
__ push(Immediate(variable->name()));
__ CallRuntime(Runtime::kDeclareEvalVar);
PrepareForBailoutForId(proxy->id(), BailoutState::NO_REGISTERS);
break;
}
case VariableLocation::MODULE:
UNREACHABLE();
}
}
void FullCodeGenerator::VisitFunctionDeclaration(
FunctionDeclaration* declaration) {
VariableProxy* proxy = declaration->proxy();
Variable* variable = proxy->var();
switch (variable->location()) {
case VariableLocation::UNALLOCATED: {
FeedbackVectorSlot slot = proxy->VariableFeedbackSlot();
DCHECK(!slot.IsInvalid());
globals_->Add(handle(Smi::FromInt(slot.ToInt()), isolate()), zone());
Handle<SharedFunctionInfo> function =
Compiler::GetSharedFunctionInfo(declaration->fun(), script(), info_);
// Check for stack-overflow exception.
if (function.is_null()) return SetStackOverflow();
globals_->Add(function, zone());
break;
}
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL: {
Comment cmnt(masm_, "[ FunctionDeclaration");
VisitForAccumulatorValue(declaration->fun());
__ mov(StackOperand(variable), result_register());
break;
}
case VariableLocation::CONTEXT: {
Comment cmnt(masm_, "[ FunctionDeclaration");
EmitDebugCheckDeclarationContext(variable);
VisitForAccumulatorValue(declaration->fun());
__ mov(ContextOperand(esi, variable->index()), result_register());
// We know that we have written a function, which is not a smi.
__ RecordWriteContextSlot(esi, Context::SlotOffset(variable->index()),
result_register(), ecx, kDontSaveFPRegs,
EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
PrepareForBailoutForId(proxy->id(), BailoutState::NO_REGISTERS);
break;
}
case VariableLocation::LOOKUP: {
Comment cmnt(masm_, "[ FunctionDeclaration");
PushOperand(variable->name());
VisitForStackValue(declaration->fun());
CallRuntimeWithOperands(Runtime::kDeclareEvalFunction);
PrepareForBailoutForId(proxy->id(), BailoutState::NO_REGISTERS);
break;
}
case VariableLocation::MODULE:
UNREACHABLE();
}
}
void FullCodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
// Call the runtime to declare the globals.
__ Push(pairs);
__ Push(Smi::FromInt(DeclareGlobalsFlags()));
__ EmitLoadTypeFeedbackVector(eax);
__ Push(eax);
__ CallRuntime(Runtime::kDeclareGlobals);
// Return value is ignored.
}
void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
Comment cmnt(masm_, "[ SwitchStatement");
Breakable nested_statement(this, stmt);
SetStatementPosition(stmt);
// Keep the switch value on the stack until a case matches.
VisitForStackValue(stmt->tag());
PrepareForBailoutForId(stmt->EntryId(), BailoutState::NO_REGISTERS);
ZoneList<CaseClause*>* clauses = stmt->cases();
CaseClause* default_clause = NULL; // Can occur anywhere in the list.
Label next_test; // Recycled for each test.
// Compile all the tests with branches to their bodies.
for (int i = 0; i < clauses->length(); i++) {
CaseClause* clause = clauses->at(i);
clause->body_target()->Unuse();
// The default is not a test, but remember it as final fall through.
if (clause->is_default()) {
default_clause = clause;
continue;
}
Comment cmnt(masm_, "[ Case comparison");
__ bind(&next_test);
next_test.Unuse();
// Compile the label expression.
VisitForAccumulatorValue(clause->label());
// Perform the comparison as if via '==='.
__ mov(edx, Operand(esp, 0)); // Switch value.
bool inline_smi_code = ShouldInlineSmiCase(Token::EQ_STRICT);
JumpPatchSite patch_site(masm_);
if (inline_smi_code) {
Label slow_case;
__ mov(ecx, edx);
__ or_(ecx, eax);
patch_site.EmitJumpIfNotSmi(ecx, &slow_case, Label::kNear);
__ cmp(edx, eax);
__ j(not_equal, &next_test);
__ Drop(1); // Switch value is no longer needed.
__ jmp(clause->body_target());
__ bind(&slow_case);
}
SetExpressionPosition(clause);
Handle<Code> ic =
CodeFactory::CompareIC(isolate(), Token::EQ_STRICT).code();
CallIC(ic, clause->CompareId());
patch_site.EmitPatchInfo();
Label skip;
__ jmp(&skip, Label::kNear);
PrepareForBailout(clause, BailoutState::TOS_REGISTER);
__ cmp(eax, isolate()->factory()->true_value());
__ j(not_equal, &next_test);
__ Drop(1);
__ jmp(clause->body_target());
__ bind(&skip);
__ test(eax, eax);
__ j(not_equal, &next_test);
__ Drop(1); // Switch value is no longer needed.
__ jmp(clause->body_target());
}
// Discard the test value and jump to the default if present, otherwise to
// the end of the statement.
__ bind(&next_test);
DropOperands(1); // Switch value is no longer needed.
if (default_clause == NULL) {
__ jmp(nested_statement.break_label());
} else {
__ jmp(default_clause->body_target());
}
// Compile all the case bodies.
for (int i = 0; i < clauses->length(); i++) {
Comment cmnt(masm_, "[ Case body");
CaseClause* clause = clauses->at(i);
__ bind(clause->body_target());
PrepareForBailoutForId(clause->EntryId(), BailoutState::NO_REGISTERS);
VisitStatements(clause->statements());
}
__ bind(nested_statement.break_label());
PrepareForBailoutForId(stmt->ExitId(), BailoutState::NO_REGISTERS);
}
void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
Comment cmnt(masm_, "[ ForInStatement");
SetStatementPosition(stmt, SKIP_BREAK);
FeedbackVectorSlot slot = stmt->ForInFeedbackSlot();
// Get the object to enumerate over.
SetExpressionAsStatementPosition(stmt->enumerable());
VisitForAccumulatorValue(stmt->enumerable());
OperandStackDepthIncrement(5);
Label loop, exit;
Iteration loop_statement(this, stmt);
increment_loop_depth();
// If the object is null or undefined, skip over the loop, otherwise convert
// it to a JS receiver. See ECMA-262 version 5, section 12.6.4.
Label convert, done_convert;
__ JumpIfSmi(eax, &convert, Label::kNear);
__ CmpObjectType(eax, FIRST_JS_RECEIVER_TYPE, ecx);
__ j(above_equal, &done_convert, Label::kNear);
__ cmp(eax, isolate()->factory()->undefined_value());
__ j(equal, &exit);
__ cmp(eax, isolate()->factory()->null_value());
__ j(equal, &exit);
__ bind(&convert);
ToObjectStub stub(isolate());
__ CallStub(&stub);
RestoreContext();
__ bind(&done_convert);
PrepareForBailoutForId(stmt->ToObjectId(), BailoutState::TOS_REGISTER);
__ push(eax);
// Check cache validity in generated code. If we cannot guarantee cache
// validity, call the runtime system to check cache validity or get the
// property names in a fixed array. Note: Proxies never have an enum cache,
// so will always take the slow path.
Label call_runtime, use_cache, fixed_array;
__ CheckEnumCache(&call_runtime);
__ mov(eax, FieldOperand(eax, HeapObject::kMapOffset));
__ jmp(&use_cache, Label::kNear);
// Get the set of properties to enumerate.
__ bind(&call_runtime);
__ push(eax);
__ CallRuntime(Runtime::kForInEnumerate);
PrepareForBailoutForId(stmt->EnumId(), BailoutState::TOS_REGISTER);
__ cmp(FieldOperand(eax, HeapObject::kMapOffset),
isolate()->factory()->meta_map());
__ j(not_equal, &fixed_array);
// We got a map in register eax. Get the enumeration cache from it.
Label no_descriptors;
__ bind(&use_cache);
__ EnumLength(edx, eax);
__ cmp(edx, Immediate(Smi::FromInt(0)));
__ j(equal, &no_descriptors);
__ LoadInstanceDescriptors(eax, ecx);
__ mov(ecx, FieldOperand(ecx, DescriptorArray::kEnumCacheOffset));
__ mov(ecx, FieldOperand(ecx, DescriptorArray::kEnumCacheBridgeCacheOffset));
// Set up the four remaining stack slots.
__ push(eax); // Map.
__ push(ecx); // Enumeration cache.
__ push(edx); // Number of valid entries for the map in the enum cache.
__ push(Immediate(Smi::FromInt(0))); // Initial index.
__ jmp(&loop);
__ bind(&no_descriptors);
__ add(esp, Immediate(kPointerSize));
__ jmp(&exit);
// We got a fixed array in register eax. Iterate through that.
__ bind(&fixed_array);
__ push(Immediate(Smi::FromInt(1))); // Smi(1) indicates slow check
__ push(eax); // Array
__ mov(eax, FieldOperand(eax, FixedArray::kLengthOffset));
__ push(eax); // Fixed array length (as smi).
PrepareForBailoutForId(stmt->PrepareId(), BailoutState::NO_REGISTERS);
__ push(Immediate(Smi::FromInt(0))); // Initial index.
// Generate code for doing the condition check.
__ bind(&loop);