Google Git
Sign in
ara-mdk / platform / external / v8 / 1e0659c275bb392c045087af4f6b0d7565cb3d77 / . / src / ia32 / codegen-ia32.cc
blob: b977db877411ac0efd03a2aaccbf2399718f88eb [file] [log] [blame]
// 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"
#if defined(V8_TARGET_ARCH_IA32)
#include "codegen-inl.h"
#include "bootstrapper.h"
#include "code-stubs.h"
#include "compiler.h"
#include "debug.h"
#include "ic-inl.h"
#include "parser.h"
#include "regexp-macro-assembler.h"
#include "register-allocator-inl.h"
#include "scopes.h"
#include "virtual-frame-inl.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm)
// -------------------------------------------------------------------------
// Platform-specific FrameRegisterState functions.
void FrameRegisterState::Save(MacroAssembler* masm) const {
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 FrameRegisterState::Restore(MacroAssembler* masm) const {
// 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));
}
}
}
#undef __
#define __ ACCESS_MASM(masm_)
// -------------------------------------------------------------------------
// Platform-specific DeferredCode functions.
void DeferredCode::SaveRegisters() {
frame_state_.Save(masm_);
}
void DeferredCode::RestoreRegisters() {
frame_state_.Restore(masm_);
}
// -------------------------------------------------------------------------
// Platform-specific RuntimeCallHelper functions.
void VirtualFrameRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
frame_state_->Save(masm);
}
void VirtualFrameRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
frame_state_->Restore(masm);
}
void StubRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
masm->EnterInternalFrame();
}
void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
masm->LeaveInternalFrame();
}
// -------------------------------------------------------------------------
// 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),
in_safe_int32_mode_(false),
safe_int32_mode_enabled_(true),
function_return_is_shadowed_(false),
in_spilled_code_(false),
jit_cookie_((FLAG_mask_constants_with_cookie) ? V8::RandomPrivate() : 0) {
}
// 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());
Comment cmnt(masm_, "[ function compiled by virtual frame code generator");
// Initialize state.
info_ = info;
ASSERT(allocator_ == NULL);
RegisterAllocator register_allocator(this);
allocator_ = &register_allocator;
ASSERT(frame_ == NULL);
frame_ = new VirtualFrame();
set_in_spilled_code(false);
// Adjust for function-level loop nesting.
ASSERT_EQ(0, loop_nesting_);
loop_nesting_ = info->is_in_loop() ? 1 : 0;
JumpTarget::set_compiling_deferred_code(false);
{
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();
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
frame_->SpillAll();
__ int3();
}
#endif
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->AsSlot();
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()->AsSlot(), NOT_CONST_INIT);
}
// 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.
ASSERT_EQ(loop_nesting_, info->is_in_loop() ? 1 : 0);
loop_nesting_ = 0;
// Code generation state must be reset.
ASSERT(state_ == NULL);
ASSERT(!function_return_is_shadowed_);
function_return_.Unuse();
DeleteFrame();
// Process any deferred code using the register allocator.
if (!HasStackOverflow()) {
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* expr,
ControlDestination* dest,
bool force_control) {
ASSERT(!in_spilled_code());
int original_height = frame_->height();
{ CodeGenState new_state(this, dest);
Visit(expr);
// 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::LoadInSafeInt32Mode(Expression* expr,
BreakTarget* unsafe_bailout) {
set_unsafe_bailout(unsafe_bailout);
set_in_safe_int32_mode(true);
Load(expr);
Result value = frame_->Pop();
ASSERT(frame_->HasNoUntaggedInt32Elements());
if (expr->GuaranteedSmiResult()) {
ConvertInt32ResultToSmi(&value);
} else {
ConvertInt32ResultToNumber(&value);
}
set_in_safe_int32_mode(false);
set_unsafe_bailout(NULL);
frame_->Push(&value);
}
void CodeGenerator::LoadWithSafeInt32ModeDisabled(Expression* expr) {
set_safe_int32_mode_enabled(false);
Load(expr);
set_safe_int32_mode_enabled(true);
}
void CodeGenerator::ConvertInt32ResultToSmi(Result* value) {
ASSERT(value->is_untagged_int32());
if (value->is_register()) {
__ add(value->reg(), Operand(value->reg()));
} else {
ASSERT(value->is_constant());
ASSERT(value->handle()->IsSmi());
}
value->set_untagged_int32(false);
value->set_type_info(TypeInfo::Smi());
}
void CodeGenerator::ConvertInt32ResultToNumber(Result* value) {
ASSERT(value->is_untagged_int32());
if (value->is_register()) {
Register val = value->reg();
JumpTarget done;
__ add(val, Operand(val));
done.Branch(no_overflow, value);
__ sar(val, 1);
// If there was an overflow, bits 30 and 31 of the original number disagree.
__ xor_(val, 0x80000000u);
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope fscope(SSE2);
__ cvtsi2sd(xmm0, Operand(val));
} else {
// Move val to ST[0] in the FPU
// Push and pop are safe with respect to the virtual frame because
// all synced elements are below the actual stack pointer.
__ push(val);
__ fild_s(Operand(esp, 0));
__ pop(val);
}
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_register());
Label allocation_failed;
__ AllocateHeapNumber(val, scratch.reg(),
no_reg, &allocation_failed);
VirtualFrame* clone = new VirtualFrame(frame_);
scratch.Unuse();
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope fscope(SSE2);
__ movdbl(FieldOperand(val, HeapNumber::kValueOffset), xmm0);
} else {
__ fstp_d(FieldOperand(val, HeapNumber::kValueOffset));
}
done.Jump(value);
// Establish the virtual frame, cloned from where AllocateHeapNumber
// jumped to allocation_failed.
RegisterFile empty_regs;
SetFrame(clone, &empty_regs);
__ bind(&allocation_failed);
if (!CpuFeatures::IsSupported(SSE2)) {
// Pop the value from the floating point stack.
__ fstp(0);
}
unsafe_bailout_->Jump();
done.Bind(value);
} else {
ASSERT(value->is_constant());
}
value->set_untagged_int32(false);
value->set_type_info(TypeInfo::Integer32());
}
void CodeGenerator::Load(Expression* expr) {
#ifdef DEBUG
int original_height = frame_->height();
#endif
ASSERT(!in_spilled_code());
// If the expression should be a side-effect-free 32-bit int computation,
// compile that SafeInt32 path, and a bailout path.
if (!in_safe_int32_mode() &&
safe_int32_mode_enabled() &&
expr->side_effect_free() &&
expr->num_bit_ops() > 2 &&
CpuFeatures::IsSupported(SSE2)) {
BreakTarget unsafe_bailout;
JumpTarget done;
unsafe_bailout.set_expected_height(frame_->height());
LoadInSafeInt32Mode(expr, &unsafe_bailout);
done.Jump();
if (unsafe_bailout.is_linked()) {
unsafe_bailout.Bind();
LoadWithSafeInt32ModeDisabled(expr);
}
done.Bind();
} else {
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(GlobalObjectOperand());
} else {
Result temp = allocator_->Allocate();
__ mov(temp.reg(), GlobalObjectOperand());
frame_->Push(&temp);
}
}
void CodeGenerator::LoadGlobalReceiver() {
Result temp = allocator_->Allocate();
Register reg = temp.reg();
__ mov(reg, GlobalObjectOperand());
__ 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->AsSlot() != NULL) {
// For a variable that rewrites to a slot, we signal it is the immediate
// subexpression of a typeof.
LoadFromSlotCheckForArguments(variable->AsSlot(), INSIDE_TYPEOF);
} 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 arguments marker value
// as a sentinel indicating that the arguments object hasn't been
// allocated yet.
frame_->Push(Factory::arguments_marker());
} 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();
Variable* shadow = scope()->arguments_shadow();
ASSERT(arguments != NULL && arguments->AsSlot() != NULL);
ASSERT(shadow != NULL && shadow->AsSlot() != 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'.
LoadFromSlot(arguments->AsSlot(), NOT_INSIDE_TYPEOF);
Result probe = frame_->Pop();
if (probe.is_constant()) {
// We have to skip updating the arguments object if it has
// been assigned a proper value.
skip_arguments = !probe.handle()->IsArgumentsMarker();
} else {
__ cmp(Operand(probe.reg()), Immediate(Factory::arguments_marker()));
probe.Unuse();
done.Branch(not_equal);
}
}
if (!skip_arguments) {
StoreToSlot(arguments->AsSlot(), NOT_CONST_INIT);
if (mode == LAZY_ARGUMENTS_ALLOCATION) done.Bind();
}
StoreToSlot(shadow->AsSlot(), 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->AsSlot() != 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;
}
// 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_integer32()) { // Also takes Smi case.
Comment cmnt(masm_, "ONLY_INTEGER_32");
if (FLAG_debug_code) {
Label ok;
__ AbortIfNotNumber(value.reg());
__ test(value.reg(), Immediate(kSmiTagMask));
__ j(zero, &ok);
__ fldz();
__ fld_d(FieldOperand(value.reg(), HeapNumber::kValueOffset));
__ FCmp();
__ j(not_zero, &ok);
__ Abort("Smi was wrapped in HeapNumber in output from bitop");
__ bind(&ok);
}
// In the integer32 case there are no Smis hidden in heap numbers, so we
// need only test for Smi zero.
__ test(value.reg(), Operand(value.reg()));
dest->false_target()->Branch(zero);
value.Unuse();
dest->Split(not_zero);
} else if (value.is_number()) {
Comment cmnt(masm_, "ONLY_NUMBER");
// Fast case if TypeInfo indicates only numbers.
if (FLAG_debug_code) {
__ AbortIfNotNumber(value.reg());
}
// Smi => false iff zero.
STATIC_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.
STATIC_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);
}
}
// Perform or call the specialized stub for a binary operation. Requires the
// three registers left, right and dst to be distinct and spilled. This
// deferred operation has up to three entry points: The main one calls the
// runtime system. The second is for when the result is a non-Smi. The
// third is for when at least one of the inputs is non-Smi and we have SSE2.
class DeferredInlineBinaryOperation: public DeferredCode {
public:
DeferredInlineBinaryOperation(Token::Value op,
Register dst,
Register left,
Register right,
TypeInfo left_info,
TypeInfo right_info,
OverwriteMode mode)
: op_(op), dst_(dst), left_(left), right_(right),
left_info_(left_info), right_info_(right_info), mode_(mode) {
set_comment("[ DeferredInlineBinaryOperation");
ASSERT(!left.is(right));
}
virtual void Generate();
// This stub makes explicit calls to SaveRegisters(), RestoreRegisters() and
// Exit().
virtual bool AutoSaveAndRestore() { return false; }
void JumpToAnswerOutOfRange(Condition cond);
void JumpToConstantRhs(Condition cond, Smi* smi_value);
Label* NonSmiInputLabel();
private:
void GenerateAnswerOutOfRange();
void GenerateNonSmiInput();
Token::Value op_;
Register dst_;
Register left_;
Register right_;
TypeInfo left_info_;
TypeInfo right_info_;
OverwriteMode mode_;
Label answer_out_of_range_;
Label non_smi_input_;
Label constant_rhs_;
Smi* smi_value_;
};
Label* DeferredInlineBinaryOperation::NonSmiInputLabel() {
if (Token::IsBitOp(op_) && CpuFeatures::IsSupported(SSE2)) {
return &non_smi_input_;
} else {
return entry_label();
}
}
void DeferredInlineBinaryOperation::JumpToAnswerOutOfRange(Condition cond) {
__ j(cond, &answer_out_of_range_);
}
void DeferredInlineBinaryOperation::JumpToConstantRhs(Condition cond,
Smi* smi_value) {
smi_value_ = smi_value;
__ j(cond, &constant_rhs_);
}
void DeferredInlineBinaryOperation::Generate() {
// Registers are not saved implicitly for this stub, so we should not
// tread on the registers that were not passed to us.
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;
if (!left_info_.IsSmi()) {
__ test(left_, Immediate(kSmiTagMask));
__ j(zero, &left_smi);
if (!left_info_.IsNumber()) {
__ 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);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(left_);
}
__ 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);
if (!right_info_.IsSmi()) {
__ test(right_, Immediate(kSmiTagMask));
__ j(zero, &right_smi);
if (!right_info_.IsNumber()) {
__ 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);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(right_);
}
__ SmiUntag(right_);
__ cvtsi2sd(xmm1, Operand(right_));
__ SmiTag(right_);
if (mode_ == OVERWRITE_RIGHT || mode_ == NO_OVERWRITE) {
__ 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);
Exit();
__ bind(&after_alloc_failure);
__ pop(left_);
__ bind(&call_runtime);
}
// Register spilling is not done implicitly for this stub.
// We can't postpone it any more now though.
SaveRegisters();
GenericBinaryOpStub stub(op_,
mode_,
NO_SMI_CODE_IN_STUB,
TypeInfo::Combine(left_info_, right_info_));
stub.GenerateCall(masm_, left_, right_);
if (!dst_.is(eax)) __ mov(dst_, eax);
RestoreRegisters();
Exit();
if (non_smi_input_.is_linked() || constant_rhs_.is_linked()) {
GenerateNonSmiInput();
}
if (answer_out_of_range_.is_linked()) {
GenerateAnswerOutOfRange();
}
}
void DeferredInlineBinaryOperation::GenerateNonSmiInput() {
// We know at least one of the inputs was not a Smi.
// This is a third entry point into the deferred code.
// We may not overwrite left_ because we want to be able
// to call the handling code for non-smi answer and it
// might want to overwrite the heap number in left_.
ASSERT(!right_.is(dst_));
ASSERT(!left_.is(dst_));
ASSERT(!left_.is(right_));
// This entry point is used for bit ops where the right hand side
// is a constant Smi and the left hand side is a heap object. It
// is also used for bit ops where both sides are unknown, but where
// at least one of them is a heap object.
bool rhs_is_constant = constant_rhs_.is_linked();
// We can't generate code for both cases.
ASSERT(!non_smi_input_.is_linked() || !constant_rhs_.is_linked());
if (FLAG_debug_code) {
__ int3(); // We don't fall through into this code.
}
__ bind(&non_smi_input_);
if (rhs_is_constant) {
__ bind(&constant_rhs_);
// In this case the input is a heap object and it is in the dst_ register.
// The left_ and right_ registers have not been initialized yet.
__ mov(right_, Immediate(smi_value_));
__ mov(left_, Operand(dst_));
if (!CpuFeatures::IsSupported(SSE2)) {
__ jmp(entry_label());
return;
} else {
CpuFeatures::Scope use_sse2(SSE2);
__ JumpIfNotNumber(dst_, left_info_, entry_label());
__ ConvertToInt32(dst_, left_, dst_, left_info_, entry_label());
__ SmiUntag(right_);
}
} else {
// We know we have SSE2 here because otherwise the label is not linked (see
// NonSmiInputLabel).
CpuFeatures::Scope use_sse2(SSE2);
// Handle the non-constant right hand side situation:
if (left_info_.IsSmi()) {
// Right is a heap object.
__ JumpIfNotNumber(right_, right_info_, entry_label());
__ ConvertToInt32(right_, right_, dst_, right_info_, entry_label());
__ mov(dst_, Operand(left_));
__ SmiUntag(dst_);
} else if (right_info_.IsSmi()) {
// Left is a heap object.
__ JumpIfNotNumber(left_, left_info_, entry_label());
__ ConvertToInt32(dst_, left_, dst_, left_info_, entry_label());
__ SmiUntag(right_);
} else {
// Here we don't know if it's one or both that is a heap object.
Label only_right_is_heap_object, got_both;
__ mov(dst_, Operand(left_));
__ SmiUntag(dst_, &only_right_is_heap_object);
// Left was a heap object.
__ JumpIfNotNumber(left_, left_info_, entry_label());
__ ConvertToInt32(dst_, left_, dst_, left_info_, entry_label());
__ SmiUntag(right_, &got_both);
// Both were heap objects.
__ rcl(right_, 1); // Put tag back.
__ JumpIfNotNumber(right_, right_info_, entry_label());
__ ConvertToInt32(right_, right_, no_reg, right_info_, entry_label());
__ jmp(&got_both);
__ bind(&only_right_is_heap_object);
__ JumpIfNotNumber(right_, right_info_, entry_label());
__ ConvertToInt32(right_, right_, no_reg, right_info_, entry_label());
__ bind(&got_both);
}
}
ASSERT(op_ == Token::BIT_AND ||
op_ == Token::BIT_OR ||
op_ == Token::BIT_XOR ||
right_.is(ecx));
switch (op_) {
case Token::BIT_AND: __ and_(dst_, Operand(right_)); break;
case Token::BIT_OR: __ or_(dst_, Operand(right_)); break;
case Token::BIT_XOR: __ xor_(dst_, Operand(right_)); break;
case Token::SHR: __ shr_cl(dst_); break;
case Token::SAR: __ sar_cl(dst_); break;
case Token::SHL: __ shl_cl(dst_); break;
default: UNREACHABLE();
}
if (op_ == Token::SHR) {
// 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.
__ test(dst_, Immediate(0xc0000000));
__ j(not_zero, &answer_out_of_range_);
} else {
// Check that the *signed* result fits in a smi.
__ cmp(dst_, 0xc0000000);
__ j(negative, &answer_out_of_range_);
}
__ SmiTag(dst_);
Exit();
}
void DeferredInlineBinaryOperation::GenerateAnswerOutOfRange() {
Label after_alloc_failure2;
Label allocation_ok;
__ bind(&after_alloc_failure2);
// We have to allocate a number, causing a GC, while keeping hold of
// the answer in dst_. The answer is not a Smi. We can't just call the
// runtime shift function here because we already threw away the inputs.
__ xor_(left_, Operand(left_));
__ shl(dst_, 1); // Put top bit in carry flag and Smi tag the low bits.
__ rcr(left_, 1); // Rotate with carry.
__ push(dst_); // Smi tagged low 31 bits.
__ push(left_); // 0 or 0x80000000, which is Smi tagged in both cases.
__ CallRuntime(Runtime::kNumberAlloc, 0);
if (!left_.is(eax)) {
__ mov(left_, eax);
}
__ pop(right_); // High bit.
__ pop(dst_); // Low 31 bits.
__ shr(dst_, 1); // Put 0 in top bit.
__ or_(dst_, Operand(right_));
__ jmp(&allocation_ok);
// This is the second entry point to the deferred code. It is used only by
// the bit operations.
// The dst_ register has the answer. It is not Smi tagged. If mode_ is
// OVERWRITE_LEFT then left_ must contain either an overwritable heap number
// or a Smi.
// Put a heap number pointer in left_.
__ bind(&answer_out_of_range_);
SaveRegisters();
if (mode_ == OVERWRITE_LEFT) {
__ test(left_, Immediate(kSmiTagMask));
__ j(not_zero, &allocation_ok);
}
// This trashes right_.
__ AllocateHeapNumber(left_, right_, no_reg, &after_alloc_failure2);
__ bind(&allocation_ok);
if (CpuFeatures::IsSupported(SSE2) && op_ != Token::SHR) {
CpuFeatures::Scope use_sse2(SSE2);
ASSERT(Token::IsBitOp(op_));
// Signed conversion.
__ cvtsi2sd(xmm0, Operand(dst_));
__ movdbl(FieldOperand(left_, HeapNumber::kValueOffset), xmm0);
} else {
if (op_ == Token::SHR) {
__ push(Immediate(0)); // High word of unsigned value.
__ push(dst_);
__ fild_d(Operand(esp, 0));
__ Drop(2);
} else {
ASSERT(Token::IsBitOp(op_));
__ push(dst_);
__ fild_s(Operand(esp, 0)); // Signed conversion.
__ pop(dst_);
}
__ fstp_d(FieldOperand(left_, HeapNumber::kValueOffset));
}
__ mov(dst_, left_);
RestoreRegisters();
Exit();
}
static TypeInfo CalculateTypeInfo(TypeInfo operands_type,
Token::Value op,
const Result& right,
const Result& left) {
// Set TypeInfo of result according to the operation performed.
// Rely on the fact that smis have a 31 bit payload on ia32.
STATIC_ASSERT(kSmiValueSize == 31);
switch (op) {
case Token::COMMA:
return right.type_info();
case Token::OR:
case Token::AND:
// Result type can be either of the two input types.
return operands_type;
case Token::BIT_AND: {
// Anding with positive Smis will give you a Smi.
if (right.is_constant() && right.handle()->IsSmi() &&
Smi::cast(*right.handle())->value() >= 0) {
return TypeInfo::Smi();
} else if (left.is_constant() && left.handle()->IsSmi() &&
Smi::cast(*left.handle())->value() >= 0) {
return TypeInfo::Smi();
}
return (operands_type.IsSmi())
? TypeInfo::Smi()
: TypeInfo::Integer32();
}
case Token::BIT_OR: {
// Oring with negative Smis will give you a Smi.
if (right.is_constant() && right.handle()->IsSmi() &&
Smi::cast(*right.handle())->value() < 0) {
return TypeInfo::Smi();
} else if (left.is_constant() && left.handle()->IsSmi() &&
Smi::cast(*left.handle())->value() < 0) {
return TypeInfo::Smi();
}
return (operands_type.IsSmi())
? TypeInfo::Smi()
: TypeInfo::Integer32();
}
case Token::BIT_XOR:
// Result is always a 32 bit integer. Smi property of inputs is preserved.
return (operands_type.IsSmi())
? TypeInfo::Smi()
: TypeInfo::Integer32();
case Token::SAR:
if (left.is_smi()) return TypeInfo::Smi();
// Result is a smi if we shift by a constant >= 1, otherwise an integer32.
// Shift amount is masked with 0x1F (ECMA standard 11.7.2).
return (right.is_constant() && right.handle()->IsSmi()
&& (Smi::cast(*right.handle())->value() & 0x1F) >= 1)
? TypeInfo::Smi()
: TypeInfo::Integer32();
case Token::SHR:
// Result is a smi if we shift by a constant >= 2, an integer32 if
// we shift by 1, and an unsigned 32-bit integer if we shift by 0.
if (right.is_constant() && right.handle()->IsSmi()) {
int shift_amount = Smi::cast(*right.handle())->value() & 0x1F;
if (shift_amount > 1) {
return TypeInfo::Smi();
} else if (shift_amount > 0) {
return TypeInfo::Integer32();
}
}
return TypeInfo::Number();
case Token::ADD:
if (operands_type.IsSmi()) {
// The Integer32 range is big enough to take the sum of any two Smis.
return TypeInfo::Integer32();
} else if (operands_type.IsNumber()) {
return TypeInfo::Number();
} else if (left.type_info().IsString() || right.type_info().IsString()) {
return TypeInfo::String();
} else {
return TypeInfo::Unknown();
}
case Token::SHL:
return TypeInfo::Integer32();
case Token::SUB:
// The Integer32 range is big enough to take the difference of any two
// Smis.
return (operands_type.IsSmi()) ?
TypeInfo::Integer32() :
TypeInfo::Number();
case Token::MUL:
case Token::DIV:
case Token::MOD:
// Result is always a number.
return TypeInfo::Number();
default:
UNREACHABLE();
}
UNREACHABLE();
return TypeInfo::Unknown();
}
void CodeGenerator::GenericBinaryOperation(BinaryOperation* expr,
OverwriteMode overwrite_mode) {
Comment cmnt(masm_, "[ BinaryOperation");
Token::Value op = expr->op();
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) {
const bool left_is_string = left.type_info().IsString();
const bool right_is_string = right.type_info().IsString();
// Make sure constant strings have string type info.
ASSERT(!(left.is_constant() && left.handle()->IsString()) ||
left_is_string);
ASSERT(!(right.is_constant() && right.handle()->IsString()) ||
right_is_string);
if (left_is_string || right_is_string) {
frame_->Push(&left);
frame_->Push(&right);
Result answer;
if (left_is_string) {
if (right_is_string) {
StringAddStub stub(NO_STRING_CHECK_IN_STUB);
answer = frame_->CallStub(&stub, 2);
} else {
StringAddStub stub(NO_STRING_CHECK_LEFT_IN_STUB);
answer = frame_->CallStub(&stub, 2);
}
} else if (right_is_string) {
StringAddStub stub(NO_STRING_CHECK_RIGHT_IN_STUB);
answer = frame_->CallStub(&stub, 2);
}
answer.set_type_info(TypeInfo::String());
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.
TypeInfo operands_type =
TypeInfo::Combine(left.type_info(), right.type_info());
TypeInfo result_type = CalculateTypeInfo(operands_type, op, right, left);
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 = GenerateGenericBinaryOpStubCall(&stub, &left, &right);
} else if (right_is_smi_constant) {
answer = ConstantSmiBinaryOperation(expr, &left, right.handle(),
false, overwrite_mode);
} else if (left_is_smi_constant) {
answer = ConstantSmiBinaryOperation(expr, &right, left.handle(),
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) ||
operands_type.IsInteger32() ||
expr->type()->IsLikelySmi())) {
answer = LikelySmiBinaryOperation(expr, &left, &right, overwrite_mode);
} else {
GenericBinaryOpStub stub(op,
overwrite_mode,
NO_GENERIC_BINARY_FLAGS,
operands_type);
answer = GenerateGenericBinaryOpStubCall(&stub, &left, &right);
}
}
answer.set_type_info(result_type);
frame_->Push(&answer);
}
Result CodeGenerator::GenerateGenericBinaryOpStubCall(GenericBinaryOpStub* stub,
Result* left,
Result* right) {
if (stub->ArgsInRegistersSupported()) {
stub->SetArgsInRegisters();
return frame_->CallStub(stub, left, right);
} else {
frame_->Push(left);
frame_->Push(right);
return frame_->CallStub(stub, 2);
}
}
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(static_cast<int32_t>(unsigned_left)));
answer_object = Smi::FromInt(static_cast<int32_t>(unsigned_left));
break;
}
default:
UNREACHABLE();
break;
}
if (answer_object == Heap::undefined_value()) {
return false;
}
frame_->Push(Handle<Object>(answer_object));
return true;
}
void CodeGenerator::JumpIfBothSmiUsingTypeInfo(Result* left,
Result* right,
JumpTarget* both_smi) {
TypeInfo left_info = left->type_info();
TypeInfo right_info = right->type_info();
if (left_info.IsDouble() || left_info.IsString() ||
right_info.IsDouble() || right_info.IsString()) {
// We know that left and right are not both smi. Don't do any tests.
return;
}
if (left->reg().is(right->reg())) {
if (!left_info.IsSmi()) {
__ test(left->reg(), Immediate(kSmiTagMask));
both_smi->Branch(zero);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(left->reg());
left->Unuse();
right->Unuse();
both_smi->Jump();
}
} else if (!left_info.IsSmi()) {
if (!right_info.IsSmi()) {
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), left->reg());
__ or_(temp.reg(), Operand(right->reg()));
__ test(temp.reg(), Immediate(kSmiTagMask));
temp.Unuse();
both_smi->Branch(zero);
} else {
__ test(left->reg(), Immediate(kSmiTagMask));
both_smi->Branch(zero);
}
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(left->reg());
if (!right_info.IsSmi()) {
__ test(right->reg(), Immediate(kSmiTagMask));
both_smi->Branch(zero);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(right->reg());
left->Unuse();
right->Unuse();
both_smi->Jump();
}
}
}
void CodeGenerator::JumpIfNotBothSmiUsingTypeInfo(Register left,
Register right,
Register scratch,
TypeInfo left_info,
TypeInfo right_info,
DeferredCode* deferred) {
JumpIfNotBothSmiUsingTypeInfo(left,
right,
scratch,
left_info,
right_info,
deferred->entry_label());
}
void CodeGenerator::JumpIfNotBothSmiUsingTypeInfo(Register left,
Register right,
Register scratch,
TypeInfo left_info,
TypeInfo right_info,
Label* on_not_smi) {
if (left.is(right)) {
if (!left_info.IsSmi()) {
__ test(left, Immediate(kSmiTagMask));
__ j(not_zero, on_not_smi);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(left);
}
} else if (!left_info.IsSmi()) {
if (!right_info.IsSmi()) {
__ mov(scratch, left);
__ or_(scratch, Operand(right));
__ test(scratch, Immediate(kSmiTagMask));
__ j(not_zero, on_not_smi);
} else {
__ test(left, Immediate(kSmiTagMask));
__ j(not_zero, on_not_smi);
if (FLAG_debug_code) __ AbortIfNotSmi(right);
}
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(left);
if (!right_info.IsSmi()) {
__ test(right, Immediate(kSmiTagMask));
__ j(not_zero, on_not_smi);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(right);
}
}
}
// Implements a binary operation using a deferred code object and some
// inline code to operate on smis quickly.
Result CodeGenerator::LikelySmiBinaryOperation(BinaryOperation* expr,
Result* left,
Result* right,
OverwriteMode overwrite_mode) {
// Copy the type info because left and right may be overwritten.
TypeInfo left_type_info = left->type_info();
TypeInfo right_type_info = right->type_info();
Token::Value op = expr->op();
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);
// DeferredInlineBinaryOperation requires all the registers that it is
// told about to be spilled and distinct.
Result distinct_right = frame_->MakeDistinctAndSpilled(left, right);
// Check that left and right are smi tagged.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
(op == Token::DIV) ? eax : edx,
left->reg(),
distinct_right.reg(),
left_type_info,
right_type_info,
overwrite_mode);
JumpIfNotBothSmiUsingTypeInfo(left->reg(), right->reg(), edx,
left_type_info, right_type_info, deferred);
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. If the context of this
// expression will treat -0 like 0, do not do this test.
if (!expr->no_negative_zero()) {
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.
STATIC_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.
if (!expr->no_negative_zero()) {
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));
if (left_type_info.IsSmi()) {
if (FLAG_debug_code) __ AbortIfNotSmi(left->reg());
}
if (right_type_info.IsSmi()) {
if (FLAG_debug_code) __ AbortIfNotSmi(right->reg());
}
// We will modify right, it must be spilled.
frame_->Spill(ecx);
// DeferredInlineBinaryOperation requires all the registers that it is told
// about to be spilled and distinct. We know that right is ecx and left is
// not ecx.
frame_->Spill(left->reg());
// Use a fresh answer register to avoid spilling the left operand.
answer = allocator_->Allocate();
ASSERT(answer.is_valid());
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
answer.reg(),
left->reg(),
ecx,
left_type_info,
right_type_info,
overwrite_mode);
JumpIfNotBothSmiUsingTypeInfo(left->reg(), right->reg(), answer.reg(),
left_type_info, right_type_info,
deferred->NonSmiInputLabel());
// Untag both operands.
__ mov(answer.reg(), left->reg());
__ SmiUntag(answer.reg());
__ SmiUntag(right->reg()); // Right is ecx.
// Perform the operation.
ASSERT(right->reg().is(ecx));
switch (op) {
case Token::SAR: {
__ sar_cl(answer.reg());
if (!left_type_info.IsSmi()) {
// Check that the *signed* result fits in a smi.
__ cmp(answer.reg(), 0xc0000000);
deferred->JumpToAnswerOutOfRange(negative);
}
break;
}
case Token::SHR: {
__ 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));
deferred->JumpToAnswerOutOfRange(not_zero);
break;
}
case Token::SHL: {
__ shl_cl(answer.reg());
// Check that the *signed* result fits in a smi.
__ cmp(answer.reg(), 0xc0000000);
deferred->JumpToAnswerOutOfRange(negative);
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();
// DeferredInlineBinaryOperation requires all the registers that it is told
// about to be spilled.
Result distinct_right = frame_->MakeDistinctAndSpilled(left, right);
// 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(),
distinct_right.reg(),
left_type_info,
right_type_info,
overwrite_mode);
Label non_smi_bit_op;
if (op != Token::BIT_OR) {
JumpIfNotBothSmiUsingTypeInfo(left->reg(), right->reg(), answer.reg(),
left_type_info, right_type_info,
deferred->NonSmiInputLabel());
}
__ 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.
STATIC_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.
if (!expr->no_negative_zero()) {
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()));
__ test(answer.reg(), Immediate(kSmiTagMask));
__ j(not_zero, deferred->NonSmiInputLabel());
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,
TypeInfo type_info,
Smi* value,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
src_(src),
type_info_(type_info),
value_(value),
overwrite_mode_(overwrite_mode) {
if (type_info.IsSmi()) overwrite_mode_ = NO_OVERWRITE;
set_comment("[ DeferredInlineSmiOperation");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Register src_;
TypeInfo type_info_;
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,
TypeInfo::Combine(TypeInfo::Smi(), type_info_));
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,
TypeInfo type_info,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
type_info_(type_info),
value_(value),
src_(src),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiOperationReversed");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
TypeInfo type_info_;
Smi* value_;
Register src_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiOperationReversed::Generate() {
GenericBinaryOpStub stub(
op_,
overwrite_mode_,
NO_SMI_CODE_IN_STUB,
TypeInfo::Combine(TypeInfo::Smi(), type_info_));
stub.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,
TypeInfo type_info,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst),
type_info_(type_info),
value_(value),
overwrite_mode_(overwrite_mode) {
if (type_info_.IsSmi()) overwrite_mode_ = NO_OVERWRITE;
set_comment("[ DeferredInlineSmiAdd");
}
virtual void Generate();
private:
Register dst_;
TypeInfo type_info_;
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,
TypeInfo::Combine(TypeInfo::Smi(), type_info_));
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,
TypeInfo type_info,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst),
type_info_(type_info),
value_(value),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiAddReversed");
}
virtual void Generate();
private:
Register dst_;
TypeInfo type_info_;
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,
TypeInfo::Combine(TypeInfo::Smi(), type_info_));
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,
TypeInfo type_info,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst),
type_info_(type_info),
value_(value),
overwrite_mode_(overwrite_mode) {
if (type_info.IsSmi()) overwrite_mode_ = NO_OVERWRITE;
set_comment("[ DeferredInlineSmiSub");
}
virtual void Generate();
private:
Register dst_;
TypeInfo type_info_;
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,
TypeInfo::Combine(TypeInfo::Smi(), type_info_));
igostub.GenerateCall(masm_, dst_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
Result CodeGenerator::ConstantSmiBinaryOperation(BinaryOperation* expr,
Result* operand,
Handle<Object> value,
bool reversed,
OverwriteMode overwrite_mode) {
// Generate inline code for a binary operation when one of the
// operands is a constant smi. Consumes the argument "operand".
if (IsUnsafeSmi(value)) {
Result unsafe_operand(value);
if (reversed) {
return LikelySmiBinaryOperation(expr, &unsafe_operand, operand,
overwrite_mode);
} else {
return LikelySmiBinaryOperation(expr, operand, &unsafe_operand,
overwrite_mode);
}
}
// Get the literal value.
Smi* smi_value = Smi::cast(*value);
int int_value = smi_value->value();
Token::Value op = expr->op();
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(),
operand->type_info(),
smi_value,
overwrite_mode);
} else {
deferred = new DeferredInlineSmiAdd(operand->reg(),
operand->type_info(),
smi_value,
overwrite_mode);
}
__ add(Operand(operand->reg()), Immediate(value));
deferred->Branch(overflow);
if (!operand->type_info().IsSmi()) {
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
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(),
operand->type_info(),
overwrite_mode);
__ sub(answer.reg(), Operand(operand->reg()));
} else {
operand->ToRegister();
frame_->Spill(operand->reg());
answer = *operand;
deferred = new DeferredInlineSmiSub(operand->reg(),
operand->type_info(),
smi_value,
overwrite_mode);
__ sub(Operand(operand->reg()), Immediate(value));
}
deferred->Branch(overflow);
if (!operand->type_info().IsSmi()) {
__ test(answer.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
deferred->BindExit();
operand->Unuse();
break;
}
case Token::SAR:
if (reversed) {
Result constant_operand(value);
answer = LikelySmiBinaryOperation(expr, &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());
if (!operand->type_info().IsSmi()) {
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
operand->type_info(),
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();
} else {
if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
if (shift_value > 0) {
__ sar(operand->reg(), shift_value);
__ and_(operand->reg(), ~kSmiTagMask);
}
}
answer = *operand;
}
break;
case Token::SHR:
if (reversed) {
Result constant_operand(value);
answer = LikelySmiBinaryOperation(expr, &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(),
operand->type_info(),
smi_value,
overwrite_mode);
if (!operand->type_info().IsSmi()) {
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
__ 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) {
// Move operand into ecx and also into a second register.
// If operand is already in a register, take advantage of that.
// This lets us modify ecx, but still bail out to deferred code.
Result right;
Result right_copy_in_ecx;
TypeInfo right_type_info = operand->type_info();
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(),
right_type_info,
overwrite_mode);
__ mov(answer.reg(), Immediate(int_value));
__ sar(ecx, kSmiTagSize);
if (!right_type_info.IsSmi()) {
deferred->Branch(carry);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(right.reg());
}
__ 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(),
operand->type_info(),
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(),
operand->type_info(),
smi_value,
overwrite_mode);
if (!operand->type_info().IsSmi()) {
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
__ mov(answer.reg(), operand->reg());
STATIC_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.
STATIC_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();
// DeferredInlineBinaryOperation requires all the registers that it is
// told about to be spilled.
frame_->Spill(operand->reg());
DeferredInlineBinaryOperation* deferred = NULL;
if (!operand->type_info().IsSmi()) {
Result left = allocator()->Allocate();
ASSERT(left.is_valid());
Result right = allocator()->Allocate();
ASSERT(right.is_valid());
deferred = new DeferredInlineBinaryOperation(
op,
operand->reg(),
left.reg(),
right.reg(),
operand->type_info(),
TypeInfo::Smi(),
overwrite_mode == NO_OVERWRITE ? NO_OVERWRITE : OVERWRITE_LEFT);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->JumpToConstantRhs(not_zero, smi_value);
} else if (FLAG_debug_code) {
__ AbortIfNotSmi(operand->reg());
}
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));
}
}
if (deferred != NULL) 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(),
operand->type_info(),
smi_value,
overwrite_mode);
// Check that lowest log2(value) bits of operand are zero, and test
// smi tag at the same time.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize == 1);
__ 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(expr, &constant_operand, operand,
overwrite_mode);
} else {
answer = LikelySmiBinaryOperation(expr, 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(),
operand->type_info(),
smi_value,
overwrite_mode);
// Check for negative or non-Smi left hand side.
__ test(operand->reg(), Immediate(kSmiTagMask | kSmiSignMask));
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!
// The next case must be the default.
default: {
Result constant_operand(value);
if (reversed) {
answer = LikelySmiBinaryOperation(expr, &constant_operand, operand,
overwrite_mode);
} else {
answer = LikelySmiBinaryOperation(expr, operand, &constant_operand,
overwrite_mode);
}
break;
}
}
ASSERT(answer.is_valid());
return answer;
}
static bool CouldBeNaN(const Result& result) {
if (result.type_info().IsSmi()) return false;
if (result.type_info().IsInteger32()) return false;
if (!result.is_constant()) return true;
if (!result.handle()->IsHeapNumber()) return false;
return isnan(HeapNumber::cast(*result.handle())->value());
}
// Convert from signed to unsigned comparison to match the way EFLAGS are set
// by FPU and XMM compare instructions.
static Condition DoubleCondition(Condition cc) {
switch (cc) {
case less: return below;
case equal: return equal;
case less_equal: return below_equal;
case greater: return above;
case greater_equal: return above_equal;
default: UNREACHABLE();
}
UNREACHABLE();
return equal;
}
static CompareFlags ComputeCompareFlags(NaNInformation nan_info,
bool inline_number_compare) {
CompareFlags flags = NO_SMI_COMPARE_IN_STUB;
if (nan_info == kCantBothBeNaN) {
flags = static_cast<CompareFlags>(flags | CANT_BOTH_BE_NAN);
}
if (inline_number_compare) {
flags = static_cast<CompareFlags>(flags | NO_NUMBER_COMPARE_IN_STUB);
}
return flags;
}
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 smi, 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 &&
String::cast(*left_side.handle())->IsAsciiRepresentation());
}
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 &&
String::cast(*right_side.handle())->IsAsciiRepresentation());
}
if (left_side_constant_smi || right_side_constant_smi) {
bool is_loop_condition = (node->AsExpression() != NULL) &&
node->AsExpression()->is_loop_condition();
ConstantSmiComparison(cc, strict, dest, &left_side, &right_side,
left_side_constant_smi, right_side_constant_smi,
is_loop_condition);
} 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();
ASSERT(StringShape(String::cast(*right_val)).IsSymbol());
__ 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;
STATIC_ASSERT(kSymbolTag != 0);
// Ensure that no non-strings have the symbol bit set.
STATIC_ASSERT(LAST_TYPE < kNotStringTag + kIsSymbolMask);
__ test(temp.reg(), Immediate(kIsSymbolMask)); // Test the symbol bit.
__ j(zero, &not_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(&not_a_symbol);
}
// Call the compare stub if the left side is not a flat ascii string.
__ 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);
CompareFlags flags =
static_cast<CompareFlags>(CANT_BOTH_BE_NAN | NO_SMI_COMPARE_IN_STUB);
CompareStub stub(cc, strict, flags);
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);
// left_side is a sequential ASCII string.
left_side = Result(left_reg);
right_side = Result(right_val);
// Test string equality and comparison.
Label comparison_done;
if (cc == equal) {
__ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
Immediate(Smi::FromInt(1)));
__ j(not_equal, &comparison_done);
uint8_t char_value =
static_cast<uint8_t>(String::cast(*right_val)->Get(0));
__ cmpb(FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize),
char_value);
} else {
__ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
Immediate(Smi::FromInt(1)));
// If the length is 0 then the jump is taken and the flags
// correctly represent being less than the one-character string.
__ j(below, &comparison_done);
// Compare the first character of the string with the
// constant 1-character string.
uint8_t char_value =
static_cast<uint8_t>(String::cast(*right_val)->Get(0));
__ cmpb(FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize),
char_value);
__ j(not_equal, &comparison_done);
// If the first character is the same then the long string sorts after
// the short one.
__ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
Immediate(Smi::FromInt(1)));
}
__ bind(&comparison_done);
left_side.Unuse();
right_side.Unuse();
dest->Split(cc);
}
} else {
// Neither side is a constant Smi, constant 1-char string or constant null.
// If either side is a non-smi constant, or known to be a heap number,
// skip the smi check.
bool known_non_smi =
(left_side.is_constant() && !left_side.handle()->IsSmi()) ||
(right_side.is_constant() && !right_side.handle()->IsSmi()) ||
left_side.type_info().IsDouble() ||
right_side.type_info().IsDouble();
NaNInformation nan_info =
(CouldBeNaN(left_side) && CouldBeNaN(right_side)) ?
kBothCouldBeNaN :
kCantBothBeNaN;
// Inline number comparison handling any combination of smi's and heap
// numbers if:
// code is in a loop
// the compare operation is different from equal
// compare is not a for-loop comparison
// The reason for excluding equal is that it will most likely be done
// with smi's (not heap numbers) and the code to comparing smi's is inlined
// separately. The same reason applies for for-loop comparison which will
// also most likely be smi comparisons.
bool is_loop_condition = (node->AsExpression() != NULL)
&& node->AsExpression()->is_loop_condition();
bool inline_number_compare =
loop_nesting() > 0 && cc != equal && !is_loop_condition;
// Left and right needed in registers for the following code.
left_side.ToRegister();
right_side.ToRegister();
if (known_non_smi) {
// Inlined equality check:
// If at least one of the objects is not NaN, then if the objects
// are identical, they are equal.
if (nan_info == kCantBothBeNaN && cc == equal) {
__ cmp(left_side.reg(), Operand(right_side.reg()));
dest->true_target()->Branch(equal);
}
// Inlined number comparison:
if (inline_number_compare) {
GenerateInlineNumberComparison(&left_side, &right_side, cc, dest);
}
// End of in-line compare, call out to the compare stub. Don't include
// number comparison in the stub if it was inlined.
CompareFlags flags = ComputeCompareFlags(nan_info, inline_number_compare);
CompareStub stub(cc, strict, flags);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
__ test(answer.reg(), Operand(answer.reg()));
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();
// In-line check for comparing two smis.
JumpIfBothSmiUsingTypeInfo(&left_side, &right_side, &is_smi);
if (has_valid_frame()) {
// Inline the equality check if both operands can't be a NaN. If both
// objects are the same they are equal.
if (nan_info == kCantBothBeNaN && cc == equal) {
__ cmp(left_side.reg(), Operand(right_side.reg()));
dest->true_target()->Branch(equal);
}
// Inlined number comparison:
if (inline_number_compare) {
GenerateInlineNumberComparison(&left_side, &right_side, cc, dest);
}
// End of in-line compare, call out to the compare stub. Don't include
// number comparison in the stub if it was inlined.
CompareFlags flags =
ComputeCompareFlags(nan_info, inline_number_compare);
CompareStub stub(cc, strict, flags);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
__ test(answer.reg(), Operand(answer.reg()));
answer.Unuse();
if (is_smi.is_linked()) {
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
} else {
dest->Split(cc);
}
}
if (is_smi.is_linked()) {
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);
}
}
}
}
void CodeGenerator::ConstantSmiComparison(Condition cc,
bool strict,
ControlDestination* dest,
Result* left_side,
Result* right_side,
bool left_side_constant_smi,
bool right_side_constant_smi,
bool is_loop_condition) {
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 re-introduce 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();
if (left_side->is_smi()) {
if (FLAG_debug_code) {
__ AbortIfNotSmi(left_reg);
}
// Test smi equality and comparison by signed int comparison.
if (IsUnsafeSmi(right_side->handle())) {
right_side->ToRegister();
__ cmp(left_reg, Operand(right_side->reg()));
} else {
__ cmp(Operand(left_reg), Immediate(right_side->handle()));
}
left_side->Unuse();
right_side->Unuse();
dest->Split(cc);
} else {
// Only the case where the left side could possibly be a non-smi is left.
JumpTarget is_smi;
if (cc == equal) {
// We can do the equality comparison before the smi check.
__ cmp(Operand(left_reg), Immediate(right_side->handle()));
dest->true_target()->Branch(equal);
__ test(left_reg, Immediate(kSmiTagMask));
dest->false_target()->Branch(zero);
} else {
// Do the smi check, then the comparison.
__ test(left_reg, Immediate(kSmiTagMask));
is_smi.Branch(zero, left_side, right_side);
}
// Jump or fall through to here if we are comparing a non-smi to a
// constant smi. If the non-smi is a heap number and this is not
// a loop condition, inline the floating point code.
if (!is_loop_condition && CpuFeatures::IsSupported(SSE2)) {
// 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();
}
__ ucomisd(xmm1, xmm0);
// Jump to builtin for NaN.
not_number.Branch(parity_even, left_side);
left_side->Unuse();
dest->true_target()->Branch(DoubleCondition(cc));
dest->false_target()->Jump();
not_number.Bind(left_side);
}
// Setup and call the compare stub.
CompareFlags flags =
static_cast<CompareFlags>(CANT_BOTH_BE_NAN | NO_SMI_CODE_IN_STUB);
CompareStub stub(cc, strict, flags);
Result result = frame_->CallStub(&stub, left_side, right_side);
result.ToRegister();
__ test(result.reg(), Operand(result.reg()));
result.Unuse();
if (cc == equal) {
dest->Split(cc);
} else {
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
// It is important for performance for this case to be at the end.
is_smi.Bind(left_side, right_side);
if (IsUnsafeSmi(right_side->handle())) {
right_side->ToRegister();
__ cmp(left_reg, Operand(right_side->reg()));
} else {
__ cmp(Operand(left_reg), Immediate(right_side->handle()));
}
left_side->Unuse();
right_side->Unuse();
dest->Split(cc);
}
}
}
}
// Check that the comparison operand is a number. Jump to not_numbers jump
// target passing the left and right result if the operand is not a number.
static void CheckComparisonOperand(MacroAssembler* masm_,
Result* operand,
Result* left_side,
Result* right_side,
JumpTarget* not_numbers) {
// Perform check if operand is not known to be a number.
if (!operand->type_info().IsNumber()) {
Label done;
__ test(operand->reg(), Immediate(kSmiTagMask));
__ j(zero, &done);
__ cmp(FieldOperand(operand->reg(), HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
not_numbers->Branch(not_equal, left_side, right_side, not_taken);
__ bind(&done);
}
}
// Load a comparison operand to the FPU stack. This assumes that the operand has
// already been checked and is a number.
static void LoadComparisonOperand(MacroAssembler* masm_,
Result* operand) {
Label done;
if (operand->type_info().IsDouble()) {
// Operand is known to be a heap number, just load it.
__ fld_d(FieldOperand(operand->reg(), HeapNumber::kValueOffset));
} else if (operand->type_info().IsSmi()) {
// Operand is known to be a smi. Convert it to double and keep the original
// smi.
__ SmiUntag(operand->reg());
__ push(operand->reg());
__ fild_s(Operand(esp, 0));
__ pop(operand->reg());
__ SmiTag(operand->reg());
} else {
// Operand type not known, check for smi otherwise assume heap number.
Label smi;
__ test(operand->reg(), Immediate(kSmiTagMask));
__ j(zero, &smi);
__ fld_d(FieldOperand(operand->reg(), HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&smi);
__ SmiUntag(operand->reg());
__ push(operand->reg());
__ fild_s(Operand(esp, 0));
__ pop(operand->reg());
__ SmiTag(operand->reg());
__ jmp(&done);
}
__ bind(&done);
}
// Load a comparison operand into into a XMM register. Jump to not_numbers jump
// target passing the left and right result if the operand is not a number.
static void LoadComparisonOperandSSE2(MacroAssembler* masm_,
Result* operand,
XMMRegister xmm_reg,
Result* left_side,
Result* right_side,
JumpTarget* not_numbers) {
Label done;
if (operand->type_info().IsDouble()) {
// Operand is known to be a heap number, just load it.
__ movdbl(xmm_reg, FieldOperand(operand->reg(), HeapNumber::kValueOffset));
} else if (operand->type_info().IsSmi()) {
// Operand is known to be a smi. Convert it to double and keep the original
// smi.
__ SmiUntag(operand->reg());
__ cvtsi2sd(xmm_reg, Operand(operand->reg()));
__ SmiTag(operand->reg());
} else {
// Operand type not known, check for smi or heap number.
Label smi;
__ test(operand->reg(), Immediate(kSmiTagMask));
__ j(zero, &smi);
if (!operand->type_info().IsNumber()) {
__ cmp(FieldOperand(operand->reg(), HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
not_numbers->Branch(not_equal, left_side, right_side, taken);
}
__ movdbl(xmm_reg, FieldOperand(operand->reg(), HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&smi);
// Comvert smi to float and keep the original smi.
__ SmiUntag(operand->reg());
__ cvtsi2sd(xmm_reg, Operand(operand->reg()));
__ SmiTag(operand->reg());
__ jmp(&done);
}
__ bind(&done);
}
void CodeGenerator::GenerateInlineNumberComparison(Result* left_side,
Result* right_side,
Condition cc,
ControlDestination* dest) {
ASSERT(left_side->is_register());
ASSERT(right_side->is_register());
JumpTarget not_numbers;
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope use_sse2(SSE2);
// Load left and right operand into registers xmm0 and xmm1 and compare.
LoadComparisonOperandSSE2(masm_, left_side, xmm0, left_side, right_side,
&not_numbers);
LoadComparisonOperandSSE2(masm_, right_side, xmm1, left_side, right_side,
&not_numbers);
__ ucomisd(xmm0, xmm1);
} else {
Label check_right, compare;
// Make sure that both comparison operands are numbers.
CheckComparisonOperand(masm_, left_side, left_side, right_side,
&not_numbers);
CheckComparisonOperand(masm_, right_side, left_side, right_side,
&not_numbers);
// Load right and left operand to FPU stack and compare.
LoadComparisonOperand(masm_, right_side);
LoadComparisonOperand(masm_, left_side);
__ FCmp();
}
// Bail out if a NaN is involved.
not_numbers.Branch(parity_even, left_side, right_side, not_taken);
// Split to destination targets based on comparison.
left_side->Unuse();
right_side->Unuse();
dest->true_target()->Branch(DoubleCondition(cc));
dest->false_target()->Jump();
not_numbers.Bind(left_side, right_side);
}
// 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));
frame_->SpillTop();
}
// 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);
LoadFromSlot(scope()->arguments()->AsSlot(), NOT_INSIDE_TYPEOF);
// 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()->IsArgumentsMarker();
} else {
__ cmp(Operand(probe.reg()), Immediate(Factory::arguments_marker()));
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.
STATIC_ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
STATIC_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::kCodeEntryOffset));
__ sub(Operand(ecx), Immediate(Code::kHeaderSize - kHeapObjectTag));
Handle<Code> apply_code(Builtins::builtin(Builtins::FunctionApply));
__ cmp(Operand(ecx), 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) {
#ifdef DEBUG
int original_height = frame_->height();
#endif
ASSERT(in_spilled_code());
set_in_spilled_code(false);
VisitStatements(statements);
if (frame_ != NULL) {
frame_->SpillAll();
}
set_in_spilled_code(true);
ASSERT(!has_valid_frame() || frame_->height() == original_height);
}
void CodeGenerator::VisitStatements(ZoneList<Statement*>* statements) {
#ifdef DEBUG
int original_height = frame_->height();
#endif
ASSERT(!in_spilled_code());
for (int i = 0; has_valid_frame() && i < statements->length(); i++) {
Visit(statements->at(i));
}
ASSERT(!has_valid_frame() || frame_->height() == original_height);
}
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->AsSlot();
// 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()->positions_recorder()->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.
#ifdef DEBUG
Label check_exit_codesize;
masm_->bind(&check_exit_codesize);
#endif
// Leave the frame and return popping the arguments and the
// receiver.
frame_->Exit();
int arguments_bytes = (scope()->num_parameters() + 1) * kPointerSize;
__ Ret(arguments_bytes, ecx);
DeleteFrame();
#ifdef ENABLE_DEBUGGER_SUPPORT
// Check that the size of the code used for returning is large enough
// for the debugger's requirements.
ASSERT(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();
node->continue_target()->Unuse();
node->break_target()->Unuse();
}
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::SetTypeForStackSlot(Slot* slot, TypeInfo info) {
ASSERT(slot->type() == Slot::LOCAL || slot->type() == Slot::PARAMETER);
if (slot->type() == Slot::LOCAL) {
frame_->SetTypeForLocalAt(slot->index(), info);
} else {
frame_->SetTypeForParamAt(slot->index(), info);
}
if (FLAG_debug_code && info.IsSmi()) {
if (slot->type() == Slot::LOCAL) {
frame_->PushLocalAt(slot->index());
} else {
frame_->PushParameterAt(slot->index());
}
Result var = frame_->Pop();
var.ToRegister();
__ AbortIfNotSmi(var.reg());
}
}
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.
// We know that the loop index is a smi if it is not modified in the
// loop body and it is checked against a constant limit in the loop
// condition. In this case, we reset the static type information of the
// loop index to smi before compiling the body, the update expression, and
// the bottom check of the loop condition.
if (node->is_fast_smi_loop()) {
// Set number type of the loop variable to smi.
SetTypeForStackSlot(node->loop_variable()->AsSlot(), TypeInfo::Smi());
}
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());
}
}
// Set the type of the loop variable to smi before compiling the test
// expression if we are in a fast smi loop condition.
if (node->is_fast_smi_loop() && has_valid_frame()) {
// Set number type of the loop variable to smi.
SetTypeForStackSlot(node->loop_variable()->AsSlot(), TypeInfo::Smi());
}
// 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);
__ CmpObjectType(eax, FIRST_JS_OBJECT_TYPE, ecx);
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));
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));
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, FixedArrayElementOperand(edx, eax));
// 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.
__ test(ebx, Operand(ebx));
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());
if (!each.is_illegal()) {
if (each.size() > 0) {
// Loading a reference may leave the frame in an unspilled state.
frame_->SpillAll();
// Get the value (under the reference on the stack) from memory.
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->AsSlot() != NULL);
StoreToSlot(catch_var->AsSlot(), 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.
STATIC_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);
STATIC_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.
STATIC_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.
STATIC_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::InstantiateFunction(
Handle<SharedFunctionInfo> function_info,
bool pretenure) {
// 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() &&
function_info->num_literals() == 0 &&
!pretenure) {
FastNewClosureStub stub;
frame()->EmitPush(Immediate(function_info));
return frame()->CallStub(&stub, 1);
} else {
// Call the runtime to instantiate the function based on the
// shared function info.
frame()->EmitPush(esi);
frame()->EmitPush(Immediate(function_info));
frame()->EmitPush(Immediate(pretenure
? Factory::true_value()
: Factory::false_value()));
return frame()->CallRuntime(Runtime::kNewClosure, 3);
}
}
void CodeGenerator::VisitFunctionLiteral(FunctionLiteral* node) {
Comment cmnt(masm_, "[ FunctionLiteral");
ASSERT(!in_safe_int32_mode());
// Build the function info and instantiate it.
Handle<SharedFunctionInfo> function_info =
Compiler::BuildFunctionInfo(node, script());
// Check for stack-overflow exception.
if (function_info.is_null()) {
SetStackOverflow();
return;
}
Result result = InstantiateFunction(function_info, node->pretenure());
frame()->Push(&result);
}
void CodeGenerator::VisitSharedFunctionInfoLiteral(
SharedFunctionInfoLiteral* node) {
ASSERT(!in_safe_int32_mode());
Comment cmnt(masm_, "[ SharedFunctionInfoLiteral");
Result result = InstantiateFunction(node->shared_function_info(), false);
frame()->Push(&result);
}
void CodeGenerator::VisitConditional(Conditional* node) {
Comment cmnt(masm_, "[ Conditional");
ASSERT(!in_safe_int32_mode());
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();
}
void CodeGenerator::LoadFromSlot(Slot* slot, TypeofState typeof_state) {
if (slot->type() == Slot::LOOKUP) {
ASSERT(slot->var()->is_dynamic());
JumpTarget slow;
JumpTarget done;
Result value;
// Generate fast case for loading from slots that correspond to
// local/global variables or arguments unless they are shadowed by
// eval-introduced bindings.
EmitDynamicLoadFromSlotFastCase(slot,
typeof_state,
&value,
&slow,
&done);
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) {
value =
frame()->CallRuntime(Runtime::kLoadContextSlotNoReferenceError, 2);
} else {
value = frame()->CallRuntime(Runtime::kLoadContextSlot, 2);
}
done.Bind(&value);
frame_->Push(&value);
} 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);
frame()->EmitPush(ecx);
} else if (slot->type() == Slot::PARAMETER) {
frame()->PushParameterAt(slot->index());
} else if (slot->type() == Slot::LOCAL) {
frame()->PushLocalAt(slot->index());
} 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 temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), SlotOperand(slot, temp.reg()));
frame()->Push(&temp);
}
}
void CodeGenerator::LoadFromSlotCheckForArguments(Slot* slot,
TypeofState state) {
LoadFromSlot(slot, state);
// Bail out quickly if we're not using lazy arguments allocation.
if (ArgumentsMode() != LAZY_ARGUMENTS_ALLOCATION) return;
// ... or if the slot isn't a non-parameter arguments slot.
if (slot->type() == Slot::PARAMETER || !slot->is_arguments()) return;
// If the loaded value is a constant, we know if the arguments
// object has been lazily loaded yet.
Result result = frame()->Pop();
if (result.is_constant()) {
if (result.handle()->IsArgumentsMarker()) {
result = StoreArgumentsObject(false);
}
frame()->Push(&result);
return;
}
ASSERT(result.is_register());
// 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::arguments_marker()));
frame()->Push(&result);
exit.Branch(not_equal);
result = StoreArgumentsObject(false);
frame()->SetElementAt(0, &result);
result.Unuse();
exit.Bind();
return;
}
Result CodeGenerator::LoadFromGlobalSlotCheckExtensions(
Slot* slot,
TypeofState typeof_state,
JumpTarget* slow) {
ASSERT(!in_safe_int32_mode());
// 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::EmitDynamicLoadFromSlotFastCase(Slot* slot,
TypeofState typeof_state,
Result* result,
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);
done->Jump(result);
} else if (slot->var()->mode() == Variable::DYNAMIC_LOCAL) {
Slot* potential_slot = slot->var()->local_if_not_shadowed()->AsSlot();
Expression* rewrite = slot->var()->local_if_not_shadowed()->rewrite();
if (potential_slot != NULL) {
// Generate fast case for locals that rewrite to slots.
// 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());
}
done->Jump(result);
} else if (rewrite != NULL) {
// Generate fast case for calls of an argument function.
Property* property = rewrite->AsProperty();
if (property != NULL) {
VariableProxy* obj_proxy = property->obj()->AsVariableProxy();
Literal* key_literal = property->key()->AsLiteral();
if (obj_proxy != NULL &&
key_literal != NULL &&
obj_proxy->IsArguments() &&
key_literal->handle()->IsSmi()) {
// Load arguments object if there are no eval-introduced
// variables. Then load the argument from the arguments
// object using keyed load.
Result arguments = allocator()->Allocate();
ASSERT(arguments.is_valid());
__ mov(arguments.reg(),
ContextSlotOperandCheckExtensions(obj_proxy->var()->AsSlot(),
arguments,
slow));
frame_->Push(&arguments);
frame_->Push(key_literal->handle());
*result = EmitKeyedLoad();
done->Jump(result);
}
}
}
}
}
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* slot) {
Comment cmnt(masm_, "[ Slot");
if (in_safe_int32_mode()) {
if ((slot->type() == Slot::LOCAL && !slot->is_arguments())) {
frame()->UntaggedPushLocalAt(slot->index());
} else if (slot->type() == Slot::PARAMETER) {
frame()->UntaggedPushParameterAt(slot->index());
} else {
UNREACHABLE();
}
} else {
LoadFromSlotCheckForArguments(slot, NOT_INSIDE_TYPEOF);
}
}
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());
ASSERT(!in_safe_int32_mode());
Reference ref(this, node);
ref.GetValue();
}
}
void CodeGenerator::VisitLiteral(Literal* node) {
Comment cmnt(masm_, "[ Literal");
if (in_safe_int32_mode()) {
frame_->PushUntaggedElement(node->handle());
} else {
frame_->Push(node->handle());
}
}
void CodeGenerator::PushUnsafeSmi(Handle<Object> value) {
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ push(Immediate(bits ^ jit_cookie_));
__ xor_(Operand(esp, 0), Immediate(jit_cookie_));
}
void CodeGenerator::StoreUnsafeSmiToLocal(int offset, Handle<Object> value) {
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ mov(Operand(ebp, offset), Immediate(bits ^ jit_cookie_));
__ xor_(Operand(ebp, offset), Immediate(jit_cookie_));
}
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 ^ jit_cookie_));
__ xor_(target, jit_cookie_);
}
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);
}
class DeferredAllocateInNewSpace: public DeferredCode {
public:
DeferredAllocateInNewSpace(int size,
Register target,
int registers_to_save = 0)
: size_(size), target_(target), registers_to_save_(registers_to_save) {
ASSERT(size >= kPointerSize && size <= Heap::MaxObjectSizeInNewSpace());
ASSERT_EQ(0, registers_to_save & target.bit());
set_comment("[ DeferredAllocateInNewSpace");
}
void Generate();
private:
int size_;
Register target_;
int registers_to_save_;
};
void DeferredAllocateInNewSpace::Generate() {
for (int i = 0; i < kNumRegs; i++) {
if (registers_to_save_ & (1 << i)) {
Register save_register = { i };
__ push(save_register);
}
}
__ push(Immediate(Smi::FromInt(size_)));
__ CallRuntime(Runtime::kAllocateInNewSpace, 1);
if (!target_.is(eax)) {
__ mov(target_, eax);
}
for (int i = kNumRegs - 1; i >= 0; i--) {
if (registers_to_save_ & (1 << i)) {
Register save_register = { i };
__ pop(save_register);
}
}
}
void CodeGenerator::VisitRegExpLiteral(RegExpLiteral* node) {
ASSERT(!in_safe_int32_mode());
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();
// Register of boilerplate contains RegExp object.
Result tmp = allocator()->Allocate();
ASSERT(tmp.is_valid());
int size = JSRegExp::kSize + JSRegExp::kInObjectFieldCount * kPointerSize;
DeferredAllocateInNewSpace* allocate_fallback =
new DeferredAllocateInNewSpace(size, literals.reg());
frame_->Push(&boilerplate);
frame_->SpillTop();
__ AllocateInNewSpace(size,
literals.reg(),
tmp.reg(),
no_reg,
allocate_fallback->entry_label(),
TAG_OBJECT);
allocate_fallback->BindExit();
boilerplate = frame_->Pop();
// Copy from boilerplate to clone and return clone.
for (int i = 0; i < size; i += kPointerSize) {
__ mov(tmp.reg(), FieldOperand(boilerplate.reg(), i));
__ mov(FieldOperand(literals.reg(), i), tmp.reg());
}
frame_->Push(&literals);
}
void CodeGenerator::VisitObjectLiteral(ObjectLiteral* node) {
ASSERT(!in_safe_int32_mode());
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());
// Should the object literal have fast elements?
frame_->Push(Smi::FromInt(node->fast_elements() ? 1 : 0));
Result clone;
if (node->depth() > 1) {
clone = frame_->CallRuntime(Runtime::kCreateObjectLiteral, 4);
} else {
clone = frame_->CallRuntime(Runtime::kCreateObjectLiteralShallow, 4);
}
frame_->Push(&clone);
// Mark all computed expressions that are bound to a key that
// is shadowed by a later occurrence of the same key. For the
// marked expressions, no store code is emitted.
node->CalculateEmitStore();
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());
if (property->emit_store()) {
Result ignored =
frame_->CallStoreIC(Handle<String>::cast(key), false,
strict_mode_flag());
// A test eax instruction following the store IC call would
// indicate the presence of an inlined version of the
// store. Add a nop to indicate that there is no such
// inlined version.
__ nop();
} else {
frame_->Drop(2);
}
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());
if (property->emit_store()) {
// Ignore the result.
Result ignored = frame_->CallRuntime(Runtime::kSetProperty, 3);
} else {
frame_->Drop(3);
}
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) {
ASSERT(!in_safe_int32_mode());
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->constant_elements()->map() == Heap::fixed_cow_array_map()) {
FastCloneShallowArrayStub stub(
FastCloneShallowArrayStub::COPY_ON_WRITE_ELEMENTS, length);
clone = frame_->CallStub(&stub, 3);
__ IncrementCounter(&Counters::cow_arrays_created_stub, 1);
} else if (node->depth() > 1) {
clone = frame_->CallRuntime(Runtime::kCreateArrayLiteral, 3);
} else if (length > FastCloneShallowArrayStub::kMaximumClonedLength) {
clone = frame_->CallRuntime(Runtime::kCreateArrayLiteralShallow, 3);
} else {
FastCloneShallowArrayStub stub(
FastCloneShallowArrayStub::CLONE_ELEMENTS, 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 (!CompileTimeValue::ArrayLiteralElementNeedsInitialization(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_safe_int32_mode());
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->AsSlot();
ASSERT(slot != NULL);
// Evaluate the right-hand side.
if (node->is_compound()) {
// For a compound assignment the right-hand side is a binary operation
// between the current property value and the actual right-hand side.
LoadFromSlotCheckForArguments(slot, NOT_INSIDE_TYPEOF);
Load(node->value());
// Perform the binary operation.
bool overwrite_value = node->value()->ResultOverwriteAllowed();
// Construct the implicit binary operation.
BinaryOperation expr(node);
GenericBinaryOperation(&expr,
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
// For non-compound assignment just load the right-hand side.
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 sub-expression if necessary. If
// the receiver is trivial it is not placed on the stack at this point, but
// loaded whenever actually needed.
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());
}
// Change to slow case in the beginning of an initialization block to
// avoid the quadratic behavior of repeatedly adding fast properties.
if (node->starts_initialization_block()) {
// Initialization block consists of assignments of the form expr.x = ..., so
// this will never be an assignment to a variable, so there must be a
// receiver object.
ASSERT_EQ(NULL, var);
if (is_trivial_receiver) {
frame()->Push(prop->obj());
} else {
frame()->Dup();
}
Result ignored = frame()->CallRuntime(Runtime::kToSlowProperties, 1);
}
// Change to fast case at the end of an initialization block. To prepare for
// that add an extra copy of the receiver to the frame, so that it can be
// converted back to fast case after the assignment.
if (node->ends_initialization_block() && !is_trivial_receiver) {
frame()->Dup();
}
// Stack layout:
// [tos] : receiver (only materialized if non-trivial)
// [tos+1] : receiver if at the end of an initialization block
// Evaluate the right-hand side.
if (node->is_compound()) {
// For a compound assignment the right-hand side is a binary operation
// between the current property value and the actual right-hand side.
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()->ResultOverwriteAllowed();
// Construct the implicit binary operation.
BinaryOperation expr(node);
GenericBinaryOperation(&expr,
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
// For non-compound assignment just load the right-hand side.
Load(node->value());
}
// Stack layout:
// [tos] : value
// [tos+1] : receiver (only materialized if non-trivial)
// [tos+2] : receiver if at the end of an initialization block
// 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);
// Stack layout:
// [tos] : result
// [tos+1] : receiver if at the end of an initialization block
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);
}
// Stack layout:
// [tos] : result
ASSERT_EQ(frame()->height(), original_height + 1);
}
void CodeGenerator::EmitKeyedPropertyAssignment(Assignment* node) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
Comment cmnt(masm_, "[ Keyed Property Assignment");
Property* prop = node->target()->AsProperty();
ASSERT_NOT_NULL(prop);
// Evaluate the receiver subexpression.
Load(prop->obj());
// Change to slow case in the beginning of an initialization block to
// avoid the quadratic behavior of repeatedly adding fast properties.
if (node->starts_initialization_block()) {
frame_->Dup();
Result ignored = frame_->CallRuntime(Runtime::kToSlowProperties, 1);
}
// Change to fast case at the end of an initialization block. To prepare for
// that add an extra copy of the receiver to the frame, so that it can be
// converted back to fast case after the assignment.
if (node->ends_initialization_block()) {
frame_->Dup();
}
// Evaluate the key subexpression.
Load(prop->key());
// Stack layout:
// [tos] : key
// [tos+1] : receiver
// [tos+2] : receiver if at the end of an initialization block
// Evaluate the right-hand side.
if (node->is_compound()) {
// For a compound assignment the right-hand side is a binary operation
// between the current property value and the actual right-hand side.
// Duplicate receiver and key for loading the current property value.
frame()->PushElementAt(1);
frame()->PushElementAt(1);
Result value = EmitKeyedLoad();
frame()->Push(&value);
Load(node->value());
// Perform the binary operation.
bool overwrite_value = node->value()->ResultOverwriteAllowed();
BinaryOperation expr(node);
GenericBinaryOperation(&expr,
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
} else {
// For non-compound assignment just load the right-hand side.
Load(node->value());
}
// Stack layout:
// [tos] : value
// [tos+1] : key
// [tos+2] : receiver
// [tos+3] : receiver if at the end of an initialization block
// 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);
// Stack layout:
// [tos] : result
// [tos+1] : receiver if at the end of an initialization block
// Change to fast case at the end of an initialization block.
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);
}
// Stack layout:
// [tos] : result
ASSERT(frame()->height() == original_height + 1);
}
void CodeGenerator::VisitAssignment(Assignment* node) {
ASSERT(!in_safe_int32_mode());
#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) {
ASSERT(!in_safe_int32_mode());
Comment cmnt(masm_, "[ Throw");
Load(node->exception());
Result result = frame_->CallRuntime(Runtime::kThrow, 1);
frame_->Push(&result);
}
void CodeGenerator::VisitProperty(Property* node) {
ASSERT(!in_safe_int32_mode());
Comment cmnt(masm_, "[ Property");
Reference property(this, node);
property.GetValue();
}
void CodeGenerator::VisitCall(Call* node) {
ASSERT(!in_safe_int32_mode());
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());
// Load the arguments.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
frame_->SpillTop();
}
// Result to hold the result of the function resolution and the
// final result of the eval call.
Result result;
// If we know that eval can only be shadowed by eval-introduced
// variables we attempt to load the global eval function directly
// in generated code. If we succeed, there is no need to perform a
// context lookup in the runtime system.
JumpTarget done;
if (var->AsSlot() != NULL && var->mode() == Variable::DYNAMIC_GLOBAL) {
ASSERT(var->AsSlot()->type() == Slot::LOOKUP);
JumpTarget slow;
// Prepare the stack for the call to
// ResolvePossiblyDirectEvalNoLookup by pushing the loaded
// function, the first argument to the eval call and the
// receiver.
Result fun = LoadFromGlobalSlotCheckExtensions(var->AsSlot(),
NOT_INSIDE_TYPEOF,
&slow);
frame_->Push(&fun);
if (arg_count > 0) {
frame_->PushElementAt(arg_count);
} else {
frame_->Push(Factory::undefined_value());
}
frame_->PushParameterAt(-1);
// Push the strict mode flag.
frame_->Push(Smi::FromInt(strict_mode_flag()));
// Resolve the call.
result =
frame_->CallRuntime(Runtime::kResolvePossiblyDirectEvalNoLookup, 4);
done.Jump(&result);
slow.Bind();
}
// Prepare the stack for the call to ResolvePossiblyDirectEval by
// pushing the loaded function, the first argument to the eval
// call and the receiver.
frame_->PushElementAt(arg_count + 1);
if (arg_count > 0) {
frame_->PushElementAt(arg_count);
} else {
frame_->Push(Factory::undefined_value());
}
frame_->PushParameterAt(-1);
// Push the strict mode flag.
frame_->Push(Smi::FromInt(strict_mode_flag()));
// Resolve the call.
result = frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 4);
// If we generated fast-case code bind the jump-target where fast
// and slow case merge.
if (done.is_linked()) done.Bind(&result);
// 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));
frame_->SpillTop();
}
// 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->AsSlot() != NULL &&
var->AsSlot()->type() == Slot::LOOKUP) {
// ----------------------------------
// JavaScript examples:
//
// with (obj) foo(1, 2, 3) // foo may be in obj.
//
// function f() {};
// function g() {
// eval(...);
// f(); // f could be in extension object.
// }
// ----------------------------------
JumpTarget slow, done;
Result function;
// Generate fast case for loading functions from slots that
// correspond to local/global variables or arguments unless they
// are shadowed by eval-introduced bindings.
EmitDynamicLoadFromSlotFastCase(var->AsSlot(),
NOT_INSIDE_TYPEOF,
&function,
&slow,
&done);
slow.Bind();
// Enter the runtime system to 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);
// If fast case code has been generated, emit code to push the
// function and receiver and have the slow path jump around this
// code.
if (done.is_linked()) {
JumpTarget call;
call.Jump();
done.Bind(&function);
frame_->Push(&function);
LoadGlobalReceiver();
call.Bind();
}
// 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));
frame_->SpillTop();
}
// 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();
// Call the function.
CallWithArguments(args, RECEIVER_MIGHT_BE_VALUE, node->position());
} else {
// Push the receiver onto the frame.
Load(property->obj());
// Load the name of the function.
Load(property->key());
// Swap the name of the function and the receiver on the stack to follow
// the calling convention for call ICs.
Result key = frame_->Pop();
Result receiver = frame_->Pop();
frame_->Push(&key);
frame_->Push(&receiver);
key.Unuse();
receiver.Unuse();
// Load the arguments.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
frame_->SpillTop();
}
// Place the key on top of stack and call the IC initialization code.
frame_->PushElementAt(arg_count + 1);
CodeForSourcePosition(node->position());
Result result =
frame_->CallKeyedCallIC(RelocInfo::CODE_TARGET,
arg_count,
loop_nesting());
frame_->Drop(); // Drop the key still on the stack.
frame_->RestoreContextRegister();
frame_->Push(&result);
}
}
} 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) {
ASSERT(!in_safe_int32_mode());
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.
// Push constructor on the stack. If it's not a function it's used as
// receiver for CALL_NON_FUNCTION, otherwise the value on the stack is
// ignored.
Load(node->expression());
// 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);
frame_->Push(&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 | kSmiSignMask));
value.Unuse();
destination()->Split(zero);
}
class DeferredStringCharCodeAt : public DeferredCode {
public:
DeferredStringCharCodeAt(Register object,
Register index,
Register scratch,
Register result)
: result_(result),
char_code_at_generator_(object,
index,
scratch,
result,
&need_conversion_,
&need_conversion_,
&index_out_of_range_,
STRING_INDEX_IS_NUMBER) {}
StringCharCodeAtGenerator* fast_case_generator() {
return &char_code_at_generator_;
}
virtual void Generate() {
VirtualFrameRuntimeCallHelper call_helper(frame_state());
char_code_at_generator_.GenerateSlow(masm(), call_helper);
__ bind(&need_conversion_);
// Move the undefined value into the result register, which will
// trigger conversion.
__ Set(result_, Immediate(Factory::undefined_value()));
__ jmp(exit_label());
__ bind(&index_out_of_range_);
// When the index is out of range, the spec requires us to return
// NaN.
__ Set(result_, Immediate(Factory::nan_value()));
__ jmp(exit_label());
}
private:
Register result_;
Label need_conversion_;
Label index_out_of_range_;
StringCharCodeAtGenerator char_code_at_generator_;
};
// This generates code that performs a String.prototype.charCodeAt() call
// or returns a smi in order to trigger conversion.
void CodeGenerator::GenerateStringCharCodeAt(ZoneList<Expression*>* args) {
Comment(masm_, "[ GenerateStringCharCodeAt");
ASSERT(args->length() == 2);
Load(args->at(0));
Load(args->at(1));
Result index = frame_->Pop();
Result object = frame_->Pop();
object.ToRegister();
index.ToRegister();
// We might mutate the object register.
frame_->Spill(object.reg());
// We need two extra registers.
Result result = allocator()->Allocate();
ASSERT(result.is_valid());
Result scratch = allocator()->Allocate();
ASSERT(scratch.is_valid());
DeferredStringCharCodeAt* deferred =
new DeferredStringCharCodeAt(object.reg(),
index.reg(),
scratch.reg(),
result.reg());
deferred->fast_case_generator()->GenerateFast(masm_);
deferred->BindExit();
frame_->Push(&result);
}
class DeferredStringCharFromCode : public DeferredCode {
public:
DeferredStringCharFromCode(Register code,
Register result)
: char_from_code_generator_(code, result) {}
StringCharFromCodeGenerator* fast_case_generator() {
return &char_from_code_generator_;
}
virtual void Generate() {
VirtualFrameRuntimeCallHelper call_helper(frame_state());
char_from_code_generator_.GenerateSlow(masm(), call_helper);
}
private:
StringCharFromCodeGenerator char_from_code_generator_;
};
// Generates code for creating a one-char string from a char code.
void CodeGenerator::GenerateStringCharFromCode(ZoneList<Expression*>* args) {
Comment(masm_, "[ GenerateStringCharFromCode");
ASSERT(args->length() == 1);
Load(args->at(0));
Result code = frame_->Pop();
code.ToRegister();
ASSERT(code.is_valid());
Result result = allocator()->Allocate();
ASSERT(result.is_valid());
DeferredStringCharFromCode* deferred = new DeferredStringCharFromCode(
code.reg(), result.reg());
deferred->fast_case_generator()->GenerateFast(masm_);
deferred->BindExit();
frame_->Push(&result);
}
class DeferredStringCharAt : public DeferredCode {
public:
DeferredStringCharAt(Register object,
Register index,
Register scratch1,
Register scratch2,
Register result)
: result_(result),
char_at_generator_(object,
index,
scratch1,
scratch2,
result,
&need_conversion_,
&need_conversion_,
&index_out_of_range_,
STRING_INDEX_IS_NUMBER) {}
StringCharAtGenerator* fast_case_generator() {
return &char_at_generator_;
}
virtual void Generate() {
VirtualFrameRuntimeCallHelper call_helper(frame_state());
char_at_generator_.GenerateSlow(masm(), call_helper);
__ bind(&need_conversion_);
// Move smi zero into the result register, which will trigger
// conversion.
__ Set(result_, Immediate(Smi::FromInt(0)));
__ jmp(exit_label());
__ bind(&index_out_of_range_);
// When the index is out of range, the spec requires us to return
// the empty string.
__ Set(result_, Immediate(Factory::empty_string()));
__ jmp(exit_label());
}
private:
Register result_;
Label need_conversion_;
Label index_out_of_range_;
StringCharAtGenerator char_at_generator_;
};
// This generates code that performs a String.prototype.charAt() call
// or returns a smi in order to trigger conversion.
void CodeGenerator::GenerateStringCharAt(ZoneList<Expression*>* args) {
Comment(masm_, "[ GenerateStringCharAt");
ASSERT(args->length() == 2);
Load(args->at(0));
Load(args->at(1));
Result index = frame_->Pop();
Result object = frame_->Pop();
object.ToRegister();
index.ToRegister();
// We might mutate the object register.
frame_->Spill(object.reg());
// We need three extra registers.
Result result = allocator()->Allocate();
ASSERT(result.is_valid());
Result scratch1 = allocator()->Allocate();
ASSERT(scratch1.is_valid());
Result scratch2 = allocator()->Allocate();
ASSERT(scratch2.is_valid());
DeferredStringCharAt* deferred =
new DeferredStringCharAt(object.reg(),
index.reg(),
scratch1.reg(),
scratch2.reg(),
result.reg());
deferred->fast_case_generator()->GenerateFast(masm_);
deferred->BindExit();
frame_->Push(&result);
}
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::GenerateFastAsciiArrayJoin(ZoneList<Expression*>* args) {
Label bailout, done, one_char_separator, long_separator,
non_trivial_array, not_size_one_array, loop, loop_condition,
loop_1, loop_1_condition, loop_2, loop_2_entry, loop_3, loop_3_entry;
ASSERT(args->length() == 2);
// We will leave the separator on the stack until the end of the function.
Load(args->at(1));
// Load this to eax (= array)
Load(args->at(0));
Result array_result = frame_->Pop();
array_result.ToRegister(eax);
frame_->SpillAll();
// All aliases of the same register have disjoint lifetimes.
Register array = eax;
Register elements = no_reg; // Will be eax.
Register index = edx;
Register string_length = ecx;
Register string = esi;
Register scratch = ebx;
Register array_length = edi;
Register result_pos = no_reg; // Will be edi.
// Separator operand is already pushed.
Operand separator_operand = Operand(esp, 2 * kPointerSize);
Operand result_operand = Operand(esp, 1 * kPointerSize);
Operand array_length_operand = Operand(esp, 0);
__ sub(Operand(esp), Immediate(2 * kPointerSize));
__ cld();
// Check that the array is a JSArray
__ test(array, Immediate(kSmiTagMask));
__ j(zero, &bailout);
__ CmpObjectType(array, JS_ARRAY_TYPE, scratch);
__ j(not_equal, &bailout);
// Check that the array has fast elements.
__ test_b(FieldOperand(scratch, Map::kBitField2Offset),
1 << Map::kHasFastElements);
__ j(zero, &bailout);
// If the array has length zero, return the empty string.
__ mov(array_length, FieldOperand(array, JSArray::kLengthOffset));
__ sar(array_length, 1);
__ j(not_zero, &non_trivial_array);
__ mov(result_operand, Factory::empty_string());
__ jmp(&done);
// Save the array length.
__ bind(&non_trivial_array);
__ mov(array_length_operand, array_length);
// Save the FixedArray containing array's elements.
// End of array's live range.
elements = array;
__ mov(elements, FieldOperand(array, JSArray::kElementsOffset));
array = no_reg;
// Check that all array elements are sequential ASCII strings, and
// accumulate the sum of their lengths, as a smi-encoded value.
__ Set(index, Immediate(0));
__ Set(string_length, Immediate(0));
// Loop condition: while (index < length).
// Live loop registers: index, array_length, string,
// scratch, string_length, elements.
__ jmp(&loop_condition);
__ bind(&loop);
__ cmp(index, Operand(array_length));
__ j(greater_equal, &done);
__ mov(string, FieldOperand(elements, index,
times_pointer_size,
FixedArray::kHeaderSize));
__ test(string, Immediate(kSmiTagMask));
__ j(zero, &bailout);
__ mov(scratch, FieldOperand(string, HeapObject::kMapOffset));
__ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
__ and_(scratch, Immediate(
kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask));
__ cmp(scratch, kStringTag | kAsciiStringTag | kSeqStringTag);
__ j(not_equal, &bailout);
__ add(string_length,
FieldOperand(string, SeqAsciiString::kLengthOffset));
__ j(overflow, &bailout);
__ add(Operand(index), Immediate(1));
__ bind(&loop_condition);
__ cmp(index, Operand(array_length));
__ j(less, &loop);
// If array_length is 1, return elements[0], a string.
__ cmp(array_length, 1);
__ j(not_equal, &not_size_one_array);
__ mov(scratch, FieldOperand(elements, FixedArray::kHeaderSize));
__ mov(result_operand, scratch);
__ jmp(&done);
__ bind(&not_size_one_array);
// End of array_length live range.
result_pos = array_length;
array_length = no_reg;
// Live registers:
// string_length: Sum of string lengths, as a smi.
// elements: FixedArray of strings.
// Check that the separator is a flat ASCII string.
__ mov(string, separator_operand);
__ test(string, Immediate(kSmiTagMask));
__ j(zero, &bailout);
__ mov(scratch, FieldOperand(string, HeapObject::kMapOffset));
__ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
__ and_(scratch, Immediate(
kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask));
__ cmp(scratch, kStringTag | kAsciiStringTag | kSeqStringTag);
__ j(not_equal, &bailout);
// Add (separator length times array_length) - separator length
// to string_length.
__ mov(scratch, separator_operand);
__ mov(scratch, FieldOperand(scratch, SeqAsciiString::kLengthOffset));
__ sub(string_length, Operand(scratch)); // May be negative, temporarily.
__ imul(scratch, array_length_operand);
__ j(overflow, &bailout);
__ add(string_length, Operand(scratch));
__ j(overflow, &bailout);
__ shr(string_length, 1);
// Live registers and stack values:
// string_length
// elements
__ AllocateAsciiString(result_pos, string_length, scratch,
index, string, &bailout);
__ mov(result_operand, result_pos);
__ lea(result_pos, FieldOperand(result_pos, SeqAsciiString::kHeaderSize));
__ mov(string, separator_operand);
__ cmp(FieldOperand(string, SeqAsciiString::kLengthOffset),
Immediate(Smi::FromInt(1)));
__ j(equal, &one_char_separator);
__ j(greater, &long_separator);
// Empty separator case
__ mov(index, Immediate(0));
__ jmp(&loop_1_condition);
// Loop condition: while (index < length).
__ bind(&loop_1);
// Each iteration of the loop concatenates one string to the result.
// Live values in registers:
// index: which element of the elements array we are adding to the result.
// result_pos: the position to which we are currently copying characters.
// elements: the FixedArray of strings we are joining.
// Get string = array[index].
__ mov(string, FieldOperand(elements, index,
times_pointer_size,
FixedArray::kHeaderSize));
__ mov(string_length,
FieldOperand(string, String::kLengthOffset));
__ shr(string_length, 1);
__ lea(string,
FieldOperand(string, SeqAsciiString::kHeaderSize));
__ CopyBytes(string, result_pos, string_length, scratch);
__ add(Operand(index), Immediate(1));
__ bind(&loop_1_condition);
__ cmp(index, array_length_operand);
__ j(less, &loop_1); // End while (index < length).
__ jmp(&done);
// One-character separator case
__ bind(&one_char_separator);
// Replace separator with its ascii character value.
__ mov_b(scratch, FieldOperand(string, SeqAsciiString::kHeaderSize));
__ mov_b(separator_operand, scratch);
__ Set(index, Immediate(0));
// Jump into the loop after the code that copies the separator, so the first
// element is not preceded by a separator
__ jmp(&loop_2_entry);
// Loop condition: while (index < length).
__ bind(&loop_2);
// Each iteration of the loop concatenates one string to the result.
// Live values in registers:
// index: which element of the elements array we are adding to the result.
// result_pos: the position to which we are currently copying characters.
// Copy the separator character to the result.
__ mov_b(scratch, separator_operand);
__ mov_b(Operand(result_pos, 0), scratch);
__ inc(result_pos);
__ bind(&loop_2_entry);
// Get string = array[index].
__ mov(string, FieldOperand(elements, index,
times_pointer_size,
FixedArray::kHeaderSize));
__ mov(string_length,
FieldOperand(string, String::kLengthOffset));
__ shr(string_length, 1);
__ lea(string,
FieldOperand(string, SeqAsciiString::kHeaderSize));
__ CopyBytes(string, result_pos, string_length, scratch);
__ add(Operand(index), Immediate(1));
__ cmp(index, array_length_operand);
__ j(less, &loop_2); // End while (index < length).
__ jmp(&done);
// Long separator case (separator is more than one character).
__ bind(&long_separator);
__ Set(index, Immediate(0));
// Jump into the loop after the code that copies the separator, so the first
// element is not preceded by a separator
__ jmp(&loop_3_entry);
// Loop condition: while (index < length).
__ bind(&loop_3);
// Each iteration of the loop concatenates one string to the result.
// Live values in registers:
// index: which element of the elements array we are adding to the result.
// result_pos: the position to which we are currently copying characters.
// Copy the separator to the result.
__ mov(string, separator_operand);
__ mov(string_length,
FieldOperand(string, String::kLengthOffset));
__ shr(string_length, 1);
__ lea(string,
FieldOperand(string, SeqAsciiString::kHeaderSize));
__ CopyBytes(string, result_pos, string_length, scratch);
__ bind(&loop_3_entry);
// Get string = array[index].
__ mov(string, FieldOperand(elements, index,
times_pointer_size,
FixedArray::kHeaderSize));
__ mov(string_length,
FieldOperand(string, String::kLengthOffset));
__ shr(string_length, 1);
__ lea(string,
FieldOperand(string, SeqAsciiString::kHeaderSize));
__ CopyBytes(string, result_pos, string_length, scratch);
__ add(Operand(index), Immediate(1));
__ cmp(index, array_length_operand);
__ j(less, &loop_3); // End while (index < length).
__ jmp(&done);
__ bind(&bailout);
__ mov(result_operand, Factory::undefined_value());
__ bind(&done);
__ mov(eax, result_operand);
// Drop temp values from the stack, and restore context register.
__ add(Operand(esp), Immediate(2 * kPointerSize));
__ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
frame_->Drop(1);
frame_->Push(&array_result);
}
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.
__ test_b(FieldOperand(map.reg(), Map::kBitFieldOffset),
1 << Map::kIsUndetectable);
destination()->false_target()->Branch(not_zero);
// Do a range test for JSObject type. We can't use
// MacroAssembler::IsInstanceJSObjectType, because we are using a
// ControlDestination, so we copy its implementation here.
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
__ sub(Operand(map.reg()), Immediate(FIRST_JS_OBJECT_TYPE));
__ cmp(map.reg(), LAST_JS_OBJECT_TYPE - FIRST_JS_OBJECT_TYPE);
obj.Unuse();
map.Unuse();
destination()->Split(below_equal);
}
void CodeGenerator::GenerateIsSpecObject(ZoneList<Expression*>* args) {
// This generates a fast version of:
// (typeof(arg) === 'object' || %_ClassOf(arg) == 'RegExp' ||
// typeof(arg) == function).
// It includes undetectable objects (as opposed to IsObject).
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);
// Check that this is an object.
frame_->Spill(value.reg());
__ CmpObjectType(value.reg(), FIRST_JS_OBJECT_TYPE, value.reg());
value.Unuse();
destination()->Split(above_equal);
}
// Deferred code to check whether the String JavaScript object is safe for using
// default value of. This code is called after the bit caching this information
// in the map has been checked with the map for the object in the map_result_
// register. On return the register map_result_ contains 1 for true and 0 for
// false.
class DeferredIsStringWrapperSafeForDefaultValueOf : public DeferredCode {
public:
DeferredIsStringWrapperSafeForDefaultValueOf(Register object,
Register map_result,
Register scratch1,
Register scratch2)
: object_(object),
map_result_(map_result),
scratch1_(scratch1),
scratch2_(scratch2) { }
virtual void Generate() {
Label false_result;
// Check that map is loaded as expected.
if (FLAG_debug_code) {
__ cmp(map_result_, FieldOperand(object_, HeapObject::kMapOffset));
__ Assert(equal, "Map not in expected register");
}
// Check for fast case object. Generate false result for slow case object.
__ mov(scratch1_, FieldOperand(object_, JSObject::kPropertiesOffset));
__ mov(scratch1_, FieldOperand(scratch1_, HeapObject::kMapOffset));
__ cmp(scratch1_, Factory::hash_table_map());
__ j(equal, &false_result);
// Look for valueOf symbol in the descriptor array, and indicate false if
// found. The type is not checked, so if it is a transition it is a false
// negative.
__ mov(map_result_,
FieldOperand(map_result_, Map::kInstanceDescriptorsOffset));
__ mov(scratch1_, FieldOperand(map_result_, FixedArray::kLengthOffset));
// map_result_: descriptor array
// scratch1_: length of descriptor array
// Calculate the end of the descriptor array.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize == 1);
STATIC_ASSERT(kPointerSize == 4);
__ lea(scratch1_,
Operand(map_result_, scratch1_, times_2, FixedArray::kHeaderSize));
// Calculate location of the first key name.
__ add(Operand(map_result_),
Immediate(FixedArray::kHeaderSize +
DescriptorArray::kFirstIndex * kPointerSize));
// Loop through all the keys in the descriptor array. If one of these is the
// symbol valueOf the result is false.
Label entry, loop;
__ jmp(&entry);
__ bind(&loop);
__ mov(scratch2_, FieldOperand(map_result_, 0));
__ cmp(scratch2_, Factory::value_of_symbol());
__ j(equal, &false_result);
__ add(Operand(map_result_), Immediate(kPointerSize));
__ bind(&entry);
__ cmp(map_result_, Operand(scratch1_));
__ j(not_equal, &loop);
// Reload map as register map_result_ was used as temporary above.
__ mov(map_result_, FieldOperand(object_, HeapObject::kMapOffset));
// If a valueOf property is not found on the object check that it's
// prototype is the un-modified String prototype. If not result is false.
__ mov(scratch1_, FieldOperand(map_result_, Map::kPrototypeOffset));
__ test(scratch1_, Immediate(kSmiTagMask));
__ j(zero, &false_result);
__ mov(scratch1_, FieldOperand(scratch1_, HeapObject::kMapOffset));
__ mov(scratch2_, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ mov(scratch2_,
FieldOperand(scratch2_, GlobalObject::kGlobalContextOffset));
__ cmp(scratch1_,
ContextOperand(scratch2_,
Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX));
__ j(not_equal, &false_result);
// Set the bit in the map to indicate that it has been checked safe for
// default valueOf and set true result.
__ or_(FieldOperand(map_result_, Map::kBitField2Offset),
Immediate(1 << Map::kStringWrapperSafeForDefaultValueOf));
__ Set(map_result_, Immediate(1));
__ jmp(exit_label());
__ bind(&false_result);
// Set false result.
__ Set(map_result_, Immediate(0));
}
private:
Register object_;
Register map_result_;
Register scratch1_;
Register scratch2_;
};
void CodeGenerator::GenerateIsStringWrapperSafeForDefaultValueOf(
ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result obj = frame_->Pop(); // Pop the string wrapper.
obj.ToRegister();
ASSERT(obj.is_valid());
if (FLAG_debug_code) {
__ AbortIfSmi(obj.reg());
}
// Check whether this map has already been checked to be safe for default
// valueOf.
Result map_result = allocator()->Allocate();
ASSERT(map_result.is_valid());
__ mov(map_result.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
__ test_b(FieldOperand(map_result.reg(), Map::kBitField2Offset),
1 << Map::kStringWrapperSafeForDefaultValueOf);
destination()->true_target()->Branch(not_zero);
// We need an additional two scratch registers for the deferred code.
Result temp1 = allocator()->Allocate();
ASSERT(temp1.is_valid());
Result temp2 = allocator()->Allocate();
ASSERT(temp2.is_valid());
DeferredIsStringWrapperSafeForDefaultValueOf* deferred =
new DeferredIsStringWrapperSafeForDefaultValueOf(
obj.reg(), map_result.reg(), temp1.reg(), temp2.reg());
deferred->Branch(zero);
deferred->BindExit();
__ test(map_result.reg(), Operand(map_result.reg()));
obj.Unuse();
map_result.Unuse();
temp1.Unuse();
temp2.Unuse();
destination()->Split(not_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));
__ test_b(FieldOperand(temp.reg(), Map::kBitFieldOffset),
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);
Result fp = allocator_->Allocate();
Result result = allocator_->Allocate();
ASSERT(fp.is_valid() && result.is_valid());
Label exit;
// Get the number of formal parameters.
__ Set(result.reg(), Immediate(Smi::FromInt(scope()->num_parameters())));
// Check if the calling frame is an arguments adaptor frame.
__ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(not_equal, &exit);
// Arguments adaptor case: Read the arguments length from the
// adaptor frame.
__ mov(result.reg(),
Operand(fp.reg(), ArgumentsAdaptorFrameConstants::kLengthOffset));
__ bind(&exit);
result.set_type_info(TypeInfo::Smi());
if (FLAG_debug_code) __ AbortIfNotSmi(result.reg());
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.
__ CmpObjectType(obj.reg(), FIRST_JS_OBJECT_TYPE, obj.reg());
null.Branch(below);
// 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.
STATIC_ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
STATIC_ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
__ CmpInstanceType(obj.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::GenerateArguments(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);
STATIC_ASSERT(kSmiTag == 0); // EBP value is aligned, so it looks like a 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::GenerateRandomHeapNumber(
ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
frame_->SpillAll();
Label slow_allocate_heapnumber;
Label heapnumber_allocated;
__ AllocateHeapNumber(edi, ebx, ecx, &slow_allocate_heapnumber);
__ jmp(&heapnumber_allocated);
__ bind(&slow_allocate_heapnumber);
// Allocate a heap number.
__ CallRuntime(Runtime::kNumberAlloc, 0);
__ mov(edi, eax);
__ bind(&heapnumber_allocated);
__ PrepareCallCFunction(0, ebx);
__ CallCFunction(ExternalReference::random_uint32_function(), 0);
// Convert 32 random bits in eax to 0.(32 random bits) in a double
// by computing:
// ( 1.(20 0s)(32 random bits) x 2^20 ) - (1.0 x 2^20)).
// This is implemented on both SSE2 and FPU.
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope fscope(SSE2);
__ mov(ebx, Immediate(0x49800000)); // 1.0 x 2^20 as single.
__ movd(xmm1, Operand(ebx));
__ movd(xmm0, Operand(eax));
__ cvtss2sd(xmm1, xmm1);
__ pxor(xmm0, xmm1);
__ subsd(xmm0, xmm1);
__ movdbl(FieldOperand(edi, HeapNumber::kValueOffset), xmm0);
} else {
// 0x4130000000000000 is 1.0 x 2^20 as a double.
__ mov(FieldOperand(edi, HeapNumber::kExponentOffset),
Immediate(0x41300000));
__ mov(FieldOperand(edi, HeapNumber::kMantissaOffset), eax);
__ fld_d(FieldOperand(edi, HeapNumber::kValueOffset));
__ mov(FieldOperand(edi, HeapNumber::kMantissaOffset), Immediate(0));
__ fld_d(FieldOperand(edi, HeapNumber::kValueOffset));
__ fsubp(1);
__ fstp_d(FieldOperand(edi, HeapNumber::kValueOffset));
}
__ mov(eax, 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(4, args->length());
// 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::GenerateRegExpConstructResult(ZoneList<Expression*>* args) {
ASSERT_EQ(3, args->length());
Load(args->at(0)); // Size of array, smi.
Load(args->at(1)); // "index" property value.
Load(args->at(2)); // "input" property value.
RegExpConstructResultStub stub;
Result result = frame_->CallStub(&stub, 3);
frame_->Push(&result);
}
class DeferredSearchCache: public DeferredCode {
public:
DeferredSearchCache(Register dst, Register cache, Register key)
: dst_(dst), cache_(cache), key_(key) {
set_comment("[ DeferredSearchCache");
}
virtual void Generate();
private:
Register dst_; // on invocation Smi index of finger, on exit
// holds value being looked up.
Register cache_; // instance of JSFunctionResultCache.
Register key_; // key being looked up.
};
void DeferredSearchCache::Generate() {
Label first_loop, search_further, second_loop, cache_miss;
// Smi-tagging is equivalent to multiplying by 2.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize == 1);
Smi* kEntrySizeSmi = Smi::FromInt(JSFunctionResultCache::kEntrySize);
Smi* kEntriesIndexSmi = Smi::FromInt(JSFunctionResultCache::kEntriesIndex);
// Check the cache from finger to start of the cache.
__ bind(&first_loop);
__ sub(Operand(dst_), Immediate(kEntrySizeSmi));
__ cmp(Operand(dst_), Immediate(kEntriesIndexSmi));
__ j(less, &search_further);
__ cmp(key_, CodeGenerator::FixedArrayElementOperand(cache_, dst_));
__ j(not_equal, &first_loop);
__ mov(FieldOperand(cache_, JSFunctionResultCache::kFingerOffset), dst_);
__ mov(dst_, CodeGenerator::FixedArrayElementOperand(cache_, dst_, 1));
__ jmp(exit_label());
__ bind(&search_further);
// Check the cache from end of cache up to finger.
__ mov(dst_, FieldOperand(cache_, JSFunctionResultCache::kCacheSizeOffset));
__ bind(&second_loop);
__ sub(Operand(dst_), Immediate(kEntrySizeSmi));
// Consider prefetching into some reg.
__ cmp(dst_, FieldOperand(cache_, JSFunctionResultCache::kFingerOffset));
__ j(less_equal, &cache_miss);
__ cmp(key_, CodeGenerator::FixedArrayElementOperand(cache_, dst_));
__ j(not_equal, &second_loop);
__ mov(FieldOperand(cache_, JSFunctionResultCache::kFingerOffset), dst_);
__ mov(dst_, CodeGenerator::FixedArrayElementOperand(cache_, dst_, 1));
__ jmp(exit_label());
__ bind(&cache_miss);
__ push(cache_); // store a reference to cache
__ push(key_); // store a key
__ push(Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ push(key_);
// On ia32 function must be in edi.
__ mov(edi, FieldOperand(cache_, JSFunctionResultCache::kFactoryOffset));
ParameterCount expected(1);
__ InvokeFunction(edi, expected, CALL_FUNCTION);
// Find a place to put new cached value into.
Label add_new_entry, update_cache;
__ mov(ecx, Operand(esp, kPointerSize)); // restore the cache
// Possible optimization: cache size is constant for the given cache
// so technically we could use a constant here. However, if we have
// cache miss this optimization would hardly matter much.
// Check if we could add new entry to cache.
__ mov(ebx, FieldOperand(ecx, FixedArray::kLengthOffset));
__ cmp(ebx, FieldOperand(ecx, JSFunctionResultCache::kCacheSizeOffset));
__ j(greater, &add_new_entry);
// Check if we could evict entry after finger.
__ mov(edx, FieldOperand(ecx, JSFunctionResultCache::kFingerOffset));
__ add(Operand(edx), Immediate(kEntrySizeSmi));
__ cmp(ebx, Operand(edx));
__ j(greater, &update_cache);
// Need to wrap over the cache.
__ mov(edx, Immediate(kEntriesIndexSmi));
__ jmp(&update_cache);
__ bind(&add_new_entry);
__ mov(edx, FieldOperand(ecx, JSFunctionResultCache::kCacheSizeOffset));
__ lea(ebx, Operand(edx, JSFunctionResultCache::kEntrySize << 1));
__ mov(FieldOperand(ecx, JSFunctionResultCache::kCacheSizeOffset), ebx);
// Update the cache itself.
// edx holds the index.
__ bind(&update_cache);
__ pop(ebx); // restore the key
__ mov(FieldOperand(ecx, JSFunctionResultCache::kFingerOffset), edx);
// Store key.
__ mov(CodeGenerator::FixedArrayElementOperand(ecx, edx), ebx);
__ RecordWrite(ecx, 0, ebx, edx);
// Store value.
__ pop(ecx); // restore the cache.
__ mov(edx, FieldOperand(ecx, JSFunctionResultCache::kFingerOffset));
__ add(Operand(edx), Immediate(Smi::FromInt(1)));
__ mov(ebx, eax);
__ mov(CodeGenerator::FixedArrayElementOperand(ecx, edx), ebx);
__ RecordWrite(ecx, 0, ebx, edx);
if (!dst_.is(eax)) {
__ mov(dst_, eax);
}
}
void CodeGenerator::GenerateGetFromCache(ZoneList<Expression*>* args) {
ASSERT_EQ(2, args->length());
ASSERT_NE(NULL, args->at(0)->AsLiteral());
int cache_id = Smi::cast(*(args->at(0)->AsLiteral()->handle()))->value();
Handle<FixedArray> jsfunction_result_caches(
Top::global_context()->jsfunction_result_caches());
if (jsfunction_result_caches->length() <= cache_id) {
__ Abort("Attempt to use undefined cache.");
frame_->Push(Factory::undefined_value());
return;
}
Load(args->at(1));
Result key = frame_->Pop();
key.ToRegister();
Result cache = allocator()->Allocate();
ASSERT(cache.is_valid());
__ mov(cache.reg(), ContextOperand(esi, Context::GLOBAL_INDEX));
__ mov(cache.reg(),
FieldOperand(cache.reg(), GlobalObject::kGlobalContextOffset));
__ mov(cache.reg(),
ContextOperand(cache.reg(), Context::JSFUNCTION_RESULT_CACHES_INDEX));
__ mov(cache.reg(),
FieldOperand(cache.reg(), FixedArray::OffsetOfElementAt(cache_id)));
Result tmp = allocator()->Allocate();
ASSERT(tmp.is_valid());
DeferredSearchCache* deferred = new DeferredSearchCache(tmp.reg(),
cache.reg(),
key.reg());
// tmp.reg() now holds finger offset as a smi.
STATIC_ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ mov(tmp.reg(), FieldOperand(cache.reg(),
JSFunctionResultCache::kFingerOffset));
__ cmp(key.reg(), FixedArrayElementOperand(cache.reg(), tmp.reg()));
deferred->Branch(not_equal);
__ mov(tmp.reg(), FixedArrayElementOperand(cache.reg(), tmp.reg(), 1));
deferred->BindExit();
frame_->Push(&tmp);
}
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);
}
class DeferredSwapElements: public DeferredCode {
public:
DeferredSwapElements(Register object, Register index1, Register index2)
: object_(object), index1_(index1), index2_(index2) {
set_comment("[ DeferredSwapElements");
}
virtual void Generate();
private:
Register object_, index1_, index2_;
};
void DeferredSwapElements::Generate() {
__ push(object_);
__ push(index1_);
__ push(index2_);
__ CallRuntime(Runtime::kSwapElements, 3);
}
void CodeGenerator::GenerateSwapElements(ZoneList<Expression*>* args) {
// Note: this code assumes that indices are passed are within
// elements' bounds and refer to valid (not holes) values.
Comment cmnt(masm_, "[ GenerateSwapElements");
ASSERT_EQ(3, args->length());
Load(args->at(0));
Load(args->at(1));
Load(args->at(2));
Result index2 = frame_->Pop();
index2.ToRegister();
Result index1 = frame_->Pop();
index1.ToRegister();
Result object = frame_->Pop();
object.ToRegister();
Result tmp1 = allocator()->Allocate();
tmp1.ToRegister();
Result tmp2 = allocator()->Allocate();
tmp2.ToRegister();
frame_->Spill(object.reg());
frame_->Spill(index1.reg());
frame_->Spill(index2.reg());
DeferredSwapElements* deferred = new DeferredSwapElements(object.reg(),
index1.reg(),
index2.reg());
// Fetch the map and check if array is in fast case.
// Check that object doesn't require security checks and
// has no indexed interceptor.
__ CmpObjectType(object.reg(), FIRST_JS_OBJECT_TYPE, tmp1.reg());
deferred->Branch(below);
__ test_b(FieldOperand(tmp1.reg(), Map::kBitFieldOffset),
KeyedLoadIC::kSlowCaseBitFieldMask);
deferred->Branch(not_zero);
// Check the object's elements are in fast case and writable.
__ mov(tmp1.reg(), FieldOperand(object.reg(), JSObject::kElementsOffset));
__ cmp(FieldOperand(tmp1.reg(), HeapObject::kMapOffset),
Immediate(Factory::fixed_array_map()));
deferred->Branch(not_equal);
// Smi-tagging is equivalent to multiplying by 2.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize == 1);
// Check that both indices are smis.
__ mov(tmp2.reg(), index1.reg());
__ or_(tmp2.reg(), Operand(index2.reg()));
__ test(tmp2.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
// Check that both indices are valid.
__ mov(tmp2.reg(), FieldOperand(object.reg(), JSArray::kLengthOffset));
__ cmp(tmp2.reg(), Operand(index1.reg()));
deferred->Branch(below_equal);
__ cmp(tmp2.reg(), Operand(index2.reg()));
deferred->Branch(below_equal);
// Bring addresses into index1 and index2.
__ lea(index1.reg(), FixedArrayElementOperand(tmp1.reg(), index1.reg()));
__ lea(index2.reg(), FixedArrayElementOperand(tmp1.reg(), index2.reg()));
// Swap elements.
__ mov(object.reg(), Operand(index1.reg(), 0));
__ mov(tmp2.reg(), Operand(index2.reg(), 0));
__ mov(Operand(index2.reg(), 0), object.reg());
__ mov(Operand(index1.reg(), 0), tmp2.reg());
Label done;
__ InNewSpace(tmp1.reg(), tmp2.reg(), equal, &done);
// Possible optimization: do a check that both values are Smis
// (or them and test against Smi mask.)
__ mov(tmp2.reg(), tmp1.reg());
__ RecordWriteHelper(tmp2.reg(), index1.reg(), object.reg());
__ RecordWriteHelper(tmp1.reg(), index2.reg(), object.reg());
__ bind(&done);
deferred->BindExit();
frame_->Push(Factory::undefined_value());
}
void CodeGenerator::GenerateCallFunction(ZoneList<Expression*>* args) {
Comment cmnt(masm_, "[ GenerateCallFunction");
ASSERT(args->length() >= 2);
int n_args = args->length() - 2; // for receiver and function.
Load(args->at(0)); // receiver
for (int i = 0; i < n_args; i++) {
Load(args->at(i + 1));
}
Load(args->at(n_args + 1)); // function
Result result = frame_->CallJSFunction(n_args);
frame_->Push(&result);
}
// Generates the Math.pow method. Only handles special cases and
// branches to the runtime system for everything else. Please note
// that this function assumes that the callsite has executed ToNumber
// on both arguments.
void CodeGenerator::GenerateMathPow(ZoneList<Expression*>* args) {
ASSERT(args->length() == 2);
Load(args->at(0));
Load(args->at(1));
if (!CpuFeatures::IsSupported(SSE2)) {
Result res = frame_->CallRuntime(Runtime::kMath_pow, 2);
frame_->Push(&res);
} else {
CpuFeatures::Scope use_sse2(SSE2);
Label allocate_return;
// Load the two operands while leaving the values on the frame.
frame()->Dup();
Result exponent = frame()->Pop();
exponent.ToRegister();
frame()->Spill(exponent.reg());
frame()->PushElementAt(1);
Result base = frame()->Pop();
base.ToRegister();
frame()->Spill(base.reg());
Result answer = allocator()->Allocate();
ASSERT(answer.is_valid());
ASSERT(!exponent.reg().is(base.reg()));
JumpTarget call_runtime;
// Save 1 in xmm3 - we need this several times later on.
__ mov(answer.reg(), Immediate(1));
__ cvtsi2sd(xmm3, Operand(answer.reg()));
Label exponent_nonsmi;
Label base_nonsmi;
// If the exponent is a heap number go to that specific case.
__ test(exponent.reg(), Immediate(kSmiTagMask));
__ j(not_zero, &exponent_nonsmi);
__ test(base.reg(), Immediate(kSmiTagMask));
__ j(not_zero, &base_nonsmi);
// Optimized version when y is an integer.
Label powi;
__ SmiUntag(base.reg());
__ cvtsi2sd(xmm0, Operand(base.reg()));
__ jmp(&powi);
// exponent is smi and base is a heapnumber.
__ bind(&base_nonsmi);
__ cmp(FieldOperand(base.reg(), HeapObject::kMapOffset),
Factory::heap_number_map());
call_runtime.Branch(not_equal);
__ movdbl(xmm0, FieldOperand(base.reg(), HeapNumber::kValueOffset));
// Optimized version of pow if y is an integer.
__ bind(&powi);
__ SmiUntag(exponent.reg());
// Save exponent in base as we need to check if exponent is negative later.
// We know that base and exponent are in different registers.
__ mov(base.reg(), exponent.reg());
// Get absolute value of exponent.
Label no_neg;
__ cmp(exponent.reg(), 0);
__ j(greater_equal, &no_neg);
__ neg(exponent.reg());
__ bind(&no_neg);
// Load xmm1 with 1.
__ movsd(xmm1, xmm3);
Label while_true;
Label no_multiply;
__ bind(&while_true);
__ shr(exponent.reg(), 1);
__ j(not_carry, &no_multiply);
__ mulsd(xmm1, xmm0);
__ bind(&no_multiply);
__ test(exponent.reg(), Operand(exponent.reg()));
__ mulsd(xmm0, xmm0);
__ j(not_zero, &while_true);
// x has the original value of y - if y is negative return 1/result.
__ test(base.reg(), Operand(base.reg()));
__ j(positive, &allocate_return);
// Special case if xmm1 has reached infinity.
__ mov(answer.reg(), Immediate(0x7FB00000));
__ movd(xmm0, Operand(answer.reg()));
__ cvtss2sd(xmm0, xmm0);
__ ucomisd(xmm0, xmm1);
call_runtime.Branch(equal);
__ divsd(xmm3, xmm1);
__ movsd(xmm1, xmm3);
__ jmp(&allocate_return);
// exponent (or both) is a heapnumber - no matter what we should now work
// on doubles.
__ bind(&exponent_nonsmi);
__ cmp(FieldOperand(exponent.reg(), HeapObject::kMapOffset),
Factory::heap_number_map());
call_runtime.Branch(not_equal);
__ movdbl(xmm1, FieldOperand(exponent.reg(), HeapNumber::kValueOffset));
// Test if exponent is nan.
__ ucomisd(xmm1, xmm1);
call_runtime.Branch(parity_even);
Label base_not_smi;
Label handle_special_cases;
__ test(base.reg(), Immediate(kSmiTagMask));
__ j(not_zero, &base_not_smi);
__ SmiUntag(base.reg());
__ cvtsi2sd(xmm0, Operand(base.reg()));
__ jmp(&handle_special_cases);
__ bind(&base_not_smi);
__ cmp(FieldOperand(base.reg(), HeapObject::kMapOffset),
Factory::heap_number_map());
call_runtime.Branch(not_equal);
__ mov(answer.reg(), FieldOperand(base.reg(), HeapNumber::kExponentOffset));
__ and_(answer.reg(), HeapNumber::kExponentMask);
__ cmp(Operand(answer.reg()), Immediate(HeapNumber::kExponentMask));
// base is NaN or +/-Infinity
call_runtime.Branch(greater_equal);
__ movdbl(xmm0, FieldOperand(base.reg(), HeapNumber::kValueOffset));
// base is in xmm0 and exponent is in xmm1.
__ bind(&handle_special_cases);
Label not_minus_half;
// Test for -0.5.
// Load xmm2 with -0.5.
__ mov(answer.reg(), Immediate(0xBF000000));
__ movd(xmm2, Operand(answer.reg()));
__ cvtss2sd(xmm2, xmm2);
// xmm2 now has -0.5.
__ ucomisd(xmm2, xmm1);
__ j(not_equal, &not_minus_half);
// Calculates reciprocal of square root.
// sqrtsd returns -0 when input is -0. ECMA spec requires +0.
__ xorpd(xmm1, xmm1);
__ addsd(xmm1, xmm0);
__ sqrtsd(xmm1, xmm1);
__ divsd(xmm3, xmm1);
__ movsd(xmm1, xmm3);
__ jmp(&allocate_return);
// Test for 0.5.
__ bind(&not_minus_half);
// Load xmm2 with 0.5.
// Since xmm3 is 1 and xmm2 is -0.5 this is simply xmm2 + xmm3.
__ addsd(xmm2, xmm3);
// xmm2 now has 0.5.
__ ucomisd(xmm2, xmm1);
call_runtime.Branch(not_equal);
// Calculates square root.
// sqrtsd returns -0 when input is -0. ECMA spec requires +0.
__ xorpd(xmm1, xmm1);
__ addsd(xmm1, xmm0);
__ sqrtsd(xmm1, xmm1);
JumpTarget done;
Label failure, success;
__ bind(&allocate_return);
// Make a copy of the frame to enable us to handle allocation
// failure after the JumpTarget jump.
VirtualFrame* clone = new VirtualFrame(frame());
__ AllocateHeapNumber(answer.reg(), exponent.reg(),
base.reg(), &failure);
__ movdbl(FieldOperand(answer.reg(), HeapNumber::kValueOffset), xmm1);
// Remove the two original values from the frame - we only need those
// in the case where we branch to runtime.
frame()->Drop(2);
exponent.Unuse();
base.Unuse();
done.Jump(&answer);
// Use the copy of the original frame as our current frame.
RegisterFile empty_regs;
SetFrame(clone, &empty_regs);
// If we experience an allocation failure we branch to runtime.
__ bind(&failure);
call_runtime.Bind();
answer = frame()->CallRuntime(Runtime::kMath_pow_cfunction, 2);
done.Bind(&answer);
frame()->Push(&answer);
}
}
void CodeGenerator::GenerateMathSin(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
Load(args->at(0));
TranscendentalCacheStub stub(TranscendentalCache::SIN,
TranscendentalCacheStub::TAGGED);
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,
TranscendentalCacheStub::TAGGED);
Result result = frame_->CallStub(&stub, 1);
frame_->Push(&result);
}
void CodeGenerator::GenerateMathLog(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
Load(args->at(0));
TranscendentalCacheStub stub(TranscendentalCache::LOG,
TranscendentalCacheStub::TAGGED);
Result result = frame_->CallStub(&stub, 1);
frame_->Push(&result);
}
// Generates the Math.sqrt method. Please note - this function assumes that
// the callsite has executed ToNumber on the argument.
void CodeGenerator::GenerateMathSqrt(ZoneList<Expression*>* args) {
ASSERT_EQ(args->length(), 1);
Load(args->at(0));
if (!CpuFeatures::IsSupported(SSE2)) {
Result result = frame()->CallRuntime(Runtime::kMath_sqrt, 1);
frame()->Push(&result);
} else {
CpuFeatures::Scope use_sse2(SSE2);
// Leave original value on the frame if we need to call runtime.
frame()->Dup();
Result result = frame()->Pop();
result.ToRegister();
frame()->Spill(result.reg());
Label runtime;
Label non_smi;
Label load_done;
JumpTarget end;
__ test(result.reg(), Immediate(kSmiTagMask));
__ j(not_zero, &non_smi);
__ SmiUntag(result.reg());
__ cvtsi2sd(xmm0, Operand(result.reg()));
__ jmp(&load_done);
__ bind(&non_smi);
__ cmp(FieldOperand(result.reg(), HeapObject::kMapOffset),
Factory::heap_number_map());
__ j(not_equal, &runtime);
__ movdbl(xmm0, FieldOperand(result.reg(), HeapNumber::kValueOffset));
__ bind(&load_done);
__ sqrtsd(xmm0, xmm0);
// A copy of the virtual frame to allow us to go to runtime after the
// JumpTarget jump.
Result scratch = allocator()->Allocate();
VirtualFrame* clone = new VirtualFrame(frame());
__ AllocateHeapNumber(result.reg(), scratch.reg(), no_reg, &runtime);
__ movdbl(FieldOperand(result.reg(), HeapNumber::kValueOffset), xmm0);
frame()->Drop(1);
scratch.Unuse();
end.Jump(&result);
// We only branch to runtime if we have an allocation error.
// Use the copy of the original frame as our current frame.
RegisterFile empty_regs;
SetFrame(clone, &empty_regs);
__ bind(&runtime);
result = frame()->CallRuntime(Runtime::kMath_sqrt, 1);
end.Bind(&result);
frame()->Push(&result);
}
}
void CodeGenerator::GenerateIsRegExpEquivalent(ZoneList<Expression*>* args) {
ASSERT_EQ(2, args->length());
Load(args->at(0));
Load(args->at(1));
Result right_res = frame_->Pop();
Result left_res = frame_->Pop();
right_res.ToRegister();
left_res.ToRegister();
Result tmp_res = allocator()->Allocate();
ASSERT(tmp_res.is_valid());
Register right = right_res.reg();
Register left = left_res.reg();
Register tmp = tmp_res.reg();
right_res.Unuse();
left_res.Unuse();
tmp_res.Unuse();
__ cmp(left, Operand(right));
destination()->true_target()->Branch(equal);
// Fail if either is a non-HeapObject.
__ mov(tmp, left);
__ and_(Operand(tmp), right);
__ test(Operand(tmp), Immediate(kSmiTagMask));
destination()->false_target()->Branch(equal);
__ CmpObjectType(left, JS_REGEXP_TYPE, tmp);
destination()->false_target()->Branch(not_equal);
__ cmp(tmp, FieldOperand(right, HeapObject::kMapOffset));
destination()->false_target()->Branch(not_equal);
__ mov(tmp, FieldOperand(left, JSRegExp::kDataOffset));
__ cmp(tmp, FieldOperand(right, JSRegExp::kDataOffset));
destination()->Split(equal);
}
void CodeGenerator::GenerateHasCachedArrayIndex(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
if (FLAG_debug_code) {
__ AbortIfNotString(value.reg());
}
__ test(FieldOperand(value.reg(), String::kHashFieldOffset),
Immediate(String::kContainsCachedArrayIndexMask));
value.Unuse();
destination()->Split(zero);
}
void CodeGenerator::GenerateGetCachedArrayIndex(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result string = frame_->Pop();
string.ToRegister();
if (FLAG_debug_code) {
__ AbortIfNotString(string.reg());
}
Result number = allocator()->Allocate();
ASSERT(number.is_valid());
__ mov(number.reg(), FieldOperand(string.reg(), String::kHashFieldOffset));
__ IndexFromHash(number.reg(), number.reg());
string.Unuse();
frame_->Push(&number);
}
void CodeGenerator::VisitCallRuntime(CallRuntime* node) {
ASSERT(!in_safe_int32_mode());
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(), GlobalObjectOperand());
__ 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->AsSlot();
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 delete from 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 answer = frame_->CallRuntime(Runtime::kDeleteContextSlot, 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 {
if (in_safe_int32_mode()) {
Visit(node->expression());
Result value = frame_->Pop();
ASSERT(value.is_untagged_int32());
// Registers containing an int32 value are not multiply used.
ASSERT(!value.is_register() || !frame_->is_used(value.reg()));
value.ToRegister();
switch (op) {
case Token::SUB: {
__ neg(value.reg());
if (node->no_negative_zero()) {
// -MIN_INT is MIN_INT with the overflow flag set.
unsafe_bailout_->Branch(overflow);
} else {
// MIN_INT and 0 both have bad negations. They both have 31 zeros.
__ test(value.reg(), Immediate(0x7FFFFFFF));
unsafe_bailout_->Branch(zero);
}
break;
}
case Token::BIT_NOT: {
__ not_(value.reg());
break;
}
case Token::ADD: {
// Unary plus has no effect on int32 values.
break;
}
default:
UNREACHABLE();
break;
}
frame_->Push(&value);
} else {
Load(node->expression());
bool can_overwrite = node->expression()->ResultOverwriteAllowed();
UnaryOverwriteMode overwrite =
can_overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
bool no_negative_zero = node->expression()->no_negative_zero();
switch (op) {
case Token::NOT:
case Token::DELETE:
case Token::TYPEOF:
UNREACHABLE(); // handled above
break;
case Token::SUB: {
GenericUnaryOpStub stub(
Token::SUB,
overwrite,
NO_UNARY_FLAGS,
no_negative_zero ? kIgnoreNegativeZero : kStrictNegativeZero);
Result operand = frame_->Pop();
Result answer = frame_->CallStub(&stub, &operand);
answer.set_type_info(TypeInfo::Number());
frame_->Push(&answer);
break;
}
case Token::BIT_NOT: {
// Smi check.
JumpTarget smi_label;
JumpTarget continue_label;
Result operand = frame_->Pop();
TypeInfo operand_info = operand.type_info();
operand.ToRegister();
if (operand_info.IsSmi()) {
if (FLAG_debug_code) __ AbortIfNotSmi(operand.reg());
frame_->Spill(operand.reg());
// Set smi tag bit. It will be reset by the not operation.
__ lea(operand.reg(), Operand(operand.reg(), kSmiTagMask));
__ not_(operand.reg());
Result answer = operand;
answer.set_type_info(TypeInfo::Smi());
frame_->Push(&answer);
} else {
__ test(operand.reg(), Immediate(kSmiTagMask));
smi_label.Branch(zero, &operand, taken);
GenericUnaryOpStub stub(Token::BIT_NOT,
overwrite,
NO_UNARY_SMI_CODE_IN_STUB);
Result answer = frame_->CallStub(&stub, &operand);
continue_label.Jump(&answer);
smi_label.Bind(&answer);
answer.ToRegister();
frame_->Spill(answer.reg());
// Set smi tag bit. It will be reset by the not operation.
__ lea(answer.reg(), Operand(answer.reg(), kSmiTagMask));
__ not_(answer.reg());
continue_label.Bind(&answer);
answer.set_type_info(TypeInfo::Integer32());
frame_->Push(&answer);
}
break;
}
case Token::ADD: {
// Smi check.
JumpTarget continue_label;
Result operand = frame_->Pop();
TypeInfo operand_info = operand.type_info();
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);
if (operand_info.IsSmi()) {
answer.set_type_info(TypeInfo::Smi());
} else if (operand_info.IsInteger32()) {
answer.set_type_info(TypeInfo::Integer32());
} else {
answer.set_type_info(TypeInfo::Number());
}
frame_->Push(&answer);
break;
}
default:
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,
TypeInfo input_type)
: dst_(dst), is_increment_(is_increment), input_type_(input_type) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
bool is_increment_;
TypeInfo input_type_;
};
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)));
}
Register left;
if (input_type_.IsNumber()) {
left = dst_;
} else {
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
left = eax;
}
GenericBinaryOpStub stub(is_increment_ ? Token::ADD : Token::SUB,
NO_OVERWRITE,
NO_GENERIC_BINARY_FLAGS,
TypeInfo::Number());
stub.GenerateCall(masm_, left, Smi::FromInt(1));
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,
TypeInfo input_type)
: dst_(dst),
old_(old),
is_increment_(is_increment),
input_type_(input_type) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
Register old_;
bool is_increment_;
TypeInfo input_type_;
};
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)));
}
Register left;
if (input_type_.IsNumber()) {
__ push(dst_); // Save the input to use as the old value.
left = dst_;
} else {
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
__ push(eax); // Save the result of ToNumber to use as the old value.
left = eax;
}
GenericBinaryOpStub stub(is_increment_ ? Token::ADD : Token::SUB,
NO_OVERWRITE,
NO_GENERIC_BINARY_FLAGS,
TypeInfo::Number());
stub.GenerateCall(masm_, left, Smi::FromInt(1));
if (!dst_.is(eax)) __ mov(dst_, eax);
__ pop(old_);
}
void CodeGenerator::VisitCountOperation(CountOperation* node) {
ASSERT(!in_safe_int32_mode());
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());
// The return value for postfix operations is ToNumber(input).
// Keep more precise type info if the input is some kind of
// number already. If the input is not a number we have to wait
// for the deferred code to convert it.
if (new_value.type_info().IsNumber()) {
old_value.set_type_info(new_value.type_info());
}
}
// Ensure the new value is writable.
frame_->Spill(new_value.reg());
Result tmp;
if (new_value.is_smi()) {
if (FLAG_debug_code) __ AbortIfNotSmi(new_value.reg());
} else {
// We don't know statically if the input is a smi.
// 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 a temporary byte register before performing
// the count operation since clearing the register using xor will clear
// the overflow flag.
tmp = allocator_->AllocateByteRegisterWithoutSpilling();
if (tmp.is_valid()) {
__ Set(tmp.reg(), Immediate(0));
}
}
if (is_increment) {
__ add(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
} else {
__ sub(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
}
DeferredCode* deferred = NULL;
if (is_postfix) {
deferred = new DeferredPostfixCountOperation(new_value.reg(),
old_value.reg(),
is_increment,
new_value.type_info());
} else {
deferred = new DeferredPrefixCountOperation(new_value.reg(),
is_increment,
new_value.type_info());
}
if (new_value.is_smi()) {
// In case we have a smi as input just check for overflow.
deferred->Branch(overflow);
} else {
// 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.
// We combine the overflow and the smi tag check if we could
// successfully allocate a temporary byte register.
if (tmp.is_valid()) {
__ 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 count operations return their input converted to
// number. The case when the input is already a number is covered
// above in the allocation code for old_value.
if (is_postfix && !new_value.type_info().IsNumber()) {
old_value.set_type_info(TypeInfo::Number());
}
// The result of ++ or -- is an Integer32 if the
// input is a smi. Otherwise it is a number.
if (new_value.is_smi()) {
new_value.set_type_info(TypeInfo::Integer32());
} else {
new_value.set_type_info(TypeInfo::Number());
}
// 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::Int32BinaryOperation(BinaryOperation* node) {
Token::Value op = node->op();
Comment cmnt(masm_, "[ Int32BinaryOperation");
ASSERT(in_safe_int32_mode());
ASSERT(safe_int32_mode_enabled());
ASSERT(FLAG_safe_int32_compiler);
if (op == Token::COMMA) {
// Discard left value.
frame_->Nip(1);
return;
}
Result right = frame_->Pop();
Result left = frame_->Pop();
ASSERT(right.is_untagged_int32());
ASSERT(left.is_untagged_int32());
// Registers containing an int32 value are not multiply used.
ASSERT(!left.is_register() || !frame_->is_used(left.reg()));
ASSERT(!right.is_register() || !frame_->is_used(right.reg()));
switch (op) {
case Token::COMMA:
case Token::OR:
case Token::AND:
UNREACHABLE();
break;
case Token::BIT_OR:
case Token::BIT_XOR:
case Token::BIT_AND:
if (left.is_constant() || right.is_constant()) {
int32_t value; // Put constant in value, non-constant in left.
// Constants are known to be int32 values, from static analysis,
// or else will be converted to int32 by implicit ECMA [[ToInt32]].
if (left.is_constant()) {
ASSERT(left.handle()->IsSmi() || left.handle()->IsHeapNumber());
value = NumberToInt32(*left.handle());
left = right;
} else {
ASSERT(right.handle()->IsSmi() || right.handle()->IsHeapNumber());
value = NumberToInt32(*right.handle());
}
left.ToRegister();
if (op == Token::BIT_OR) {
__ or_(Operand(left.reg()), Immediate(value));
} else if (op == Token::BIT_XOR) {
__ xor_(Operand(left.reg()), Immediate(value));
} else {
ASSERT(op == Token::BIT_AND);
__ and_(Operand(left.reg()), Immediate(value));
}
} else {
ASSERT(left.is_register());
ASSERT(right.is_register());
if (op == Token::BIT_OR) {
__ or_(left.reg(), Operand(right.reg()));
} else if (op == Token::BIT_XOR) {
__ xor_(left.reg(), Operand(right.reg()));
} else {
ASSERT(op == Token::BIT_AND);
__ and_(left.reg(), Operand(right.reg()));
}
}
frame_->Push(&left);
right.Unuse();
break;
case Token::SAR:
case Token::SHL:
case Token::SHR: {
bool test_shr_overflow = false;
left.ToRegister();
if (right.is_constant()) {
ASSERT(right.handle()->IsSmi() || right.handle()->IsHeapNumber());
int shift_amount = NumberToInt32(*right.handle()) & 0x1F;
if (op == Token::SAR) {
__ sar(left.reg(), shift_amount);
} else if (op == Token::SHL) {
__ shl(left.reg(), shift_amount);
} else {
ASSERT(op == Token::SHR);
__ shr(left.reg(), shift_amount);
if (shift_amount == 0) test_shr_overflow = true;
}
} else {
// Move right to ecx
if (left.is_register() && left.reg().is(ecx)) {
right.ToRegister();
__ xchg(left.reg(), right.reg());
left = right; // Left is unused here, copy of right unused by Push.
} else {
right.ToRegister(ecx);
left.ToRegister();
}
if (op == Token::SAR) {
__ sar_cl(left.reg());
} else if (op == Token::SHL) {
__ shl_cl(left.reg());
} else {
ASSERT(op == Token::SHR);
__ shr_cl(left.reg());
test_shr_overflow = true;
}
}
{
Register left_reg = left.reg();
frame_->Push(&left);
right.Unuse();
if (test_shr_overflow && !node->to_int32()) {
// Uint32 results with top bit set are not Int32 values.
// If they will be forced to Int32, skip the test.
// Test is needed because shr with shift amount 0 does not set flags.
__ test(left_reg, Operand(left_reg));
unsafe_bailout_->Branch(sign);
}
}
break;
}
case Token::ADD:
case Token::SUB:
case Token::MUL:
if ((left.is_constant() && op != Token::SUB) || right.is_constant()) {
int32_t value; // Put constant in value, non-constant in left.
if (right.is_constant()) {
ASSERT(right.handle()->IsSmi() || right.handle()->IsHeapNumber());
value = NumberToInt32(*right.handle());
} else {
ASSERT(left.handle()->IsSmi() || left.handle()->IsHeapNumber());
value = NumberToInt32(*left.handle());
left = right;
}
left.ToRegister();
if (op == Token::ADD) {
__ add(Operand(left.reg()), Immediate(value));
} else if (op == Token::SUB) {
__ sub(Operand(left.reg()), Immediate(value));
} else {
ASSERT(op == Token::MUL);
__ imul(left.reg(), left.reg(), value);
}
} else {
left.ToRegister();
ASSERT(left.is_register());
ASSERT(right.is_register());
if (op == Token::ADD) {
__ add(left.reg(), Operand(right.reg()));
} else if (op == Token::SUB) {
__ sub(left.reg(), Operand(right.reg()));
} else {
ASSERT(op == Token::MUL);
// We have statically verified that a negative zero can be ignored.
__ imul(left.reg(), Operand(right.reg()));
}
}
right.Unuse();
frame_->Push(&left);
if (!node->to_int32() || op == Token::MUL) {
// If ToInt32 is called on the result of ADD, SUB, we don't
// care about overflows.
// Result of MUL can be non-representable precisely in double so
// we have to check for overflow.
unsafe_bailout_->Branch(overflow);
}
break;
case Token::DIV:
case Token::MOD: {
if (right.is_register() && (right.reg().is(eax) || right.reg().is(edx))) {
if (left.is_register() && left.reg().is(edi)) {
right.ToRegister(ebx);
} else {
right.ToRegister(edi);
}
}
left.ToRegister(eax);
Result edx_reg = allocator_->Allocate(edx);
right.ToRegister();
// The results are unused here because BreakTarget::Branch cannot handle
// live results.
Register right_reg = right.reg();
left.Unuse();
right.Unuse();
edx_reg.Unuse();
__ cmp(right_reg, 0);
// Ensure divisor is positive: no chance of non-int32 or -0 result.
unsafe_bailout_->Branch(less_equal);
__ cdq(); // Sign-extend eax into edx:eax
__ idiv(right_reg);
if (op == Token::MOD) {
// Negative zero can arise as a negative divident with a zero result.
if (!node->no_negative_zero()) {
Label not_negative_zero;
__ test(edx, Operand(edx));
__ j(not_zero, &not_negative_zero);
__ test(eax, Operand(eax));
unsafe_bailout_->Branch(negative);
__ bind(&not_negative_zero);
}
Result edx_result(edx, TypeInfo::Integer32());
edx_result.set_untagged_int32(true);
frame_->Push(&edx_result);
} else {
ASSERT(op == Token::DIV);
__ test(edx, Operand(edx));
unsafe_bailout_->Branch(not_equal);
Result eax_result(eax, TypeInfo::Integer32());
eax_result.set_untagged_int32(true);
frame_->Push(&eax_result);
}
break;
}
default:
UNREACHABLE();
break;
}
}
void CodeGenerator::GenerateLogicalBooleanOperation(BinaryOperation* node) {
// 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 (node->op() == Token::AND) {
ASSERT(!in_safe_int32_mode());
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 {
ASSERT(node->op() == Token::OR);
ASSERT(!in_safe_int32_mode());
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();
}
}
}
void CodeGenerator::VisitBinaryOperation(BinaryOperation* node) {
Comment cmnt(masm_, "[ BinaryOperation");
if (node->op() == Token::AND || node->op() == Token::OR) {
GenerateLogicalBooleanOperation(node);
} else if (in_safe_int32_mode()) {
Visit(node->left());
Visit(node->right());
Int32BinaryOperation(node);
} 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()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_LEFT;
} else if (node->right()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_RIGHT;
}
if (node->left()->IsTrivial()) {
Load(node->right());
Result right = frame_->Pop();
frame_->Push(node->left());
frame_->Push(&right);
} else {
Load(node->left());
Load(node->right());
}
GenericBinaryOperation(node, overwrite_mode);
}
}
void CodeGenerator::VisitThisFunction(ThisFunction* node) {
ASSERT(!in_safe_int32_mode());
frame_->PushFunction();
}
void CodeGenerator::VisitCompareOperation(CompareOperation* node) {
ASSERT(!in_safe_int32_mode());
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));
__ test_b(FieldOperand(temp.reg(), Map::kBitFieldOffset),
1 << Map::kIsUndetectable);
destination()->false_target()->Branch(not_zero);
__ CmpInstanceType(temp.reg(), FIRST_NONSTRING_TYPE);
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));
__ test_b(FieldOperand(answer.reg(), Map::kBitFieldOffset),
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.
__ test_b(FieldOperand(map.reg(), Map::kBitFieldOffset),
1 << Map::kIsUndetectable);
destination()->false_target()->Branch(not_zero);
// Do a range test for JSObject type. We can't use
// MacroAssembler::IsInstanceJSObjectType, because we are using a
// ControlDestination, so we copy its implementation here.
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
__ sub(Operand(map.reg()), Immediate(FIRST_JS_OBJECT_TYPE));
__ cmp(map.reg(), LAST_JS_OBJECT_TYPE - FIRST_JS_OBJECT_TYPE);
answer.Unuse();
map.Unuse();
destination()->Split(below_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(InstanceofStub::kNoFlags);
Result answer = frame_->CallStub(&stub, 2);
answer.ToRegister();
__ test(answer.reg(), Operand(answer.reg()));
answer.Unuse();
destination()->Split(zero);
return;
}
default:
UNREACHABLE();
}
if (left->IsTrivial()) {
if (!left_already_loaded) {
Load(right);
Result right_result = frame_->Pop();
frame_->Push(left);
frame_->Push(&right_result);
} else {
Load(right);
}
} else {
if (!left_already_loaded) Load(left);
Load(right);
}
Comparison(node, cc, strict, destination());
}
void CodeGenerator::VisitCompareToNull(CompareToNull* node) {
ASSERT(!in_safe_int32_mode());
Comment cmnt(masm_, "[ CompareToNull");
Load(node->expression());
Result operand = frame_->Pop();
operand.ToRegister();
__ cmp(operand.reg(), Factory::null_value());
if (node->is_strict()) {
operand.Unuse();
destination()->Split(equal);
} else {
// The 'null' value is only equal to 'undefined' if using non-strict
// comparisons.
destination()->true_target()->Branch(equal);
__ cmp(operand.reg(), Factory::undefined_value());
destination()->true_target()->Branch(equal);
__ test(operand.reg(), Immediate(kSmiTagMask));
destination()->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));
__ test_b(FieldOperand(temp.reg(), Map::kBitFieldOffset),
1 << Map::kIsUndetectable);
temp.Unuse();
operand.Unuse();
destination()->Split(not_zero);
}
}
#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,
bool is_contextual)
: dst_(dst),
receiver_(receiver),
name_(name),
is_contextual_(is_contextual),
is_dont_delete_(false) {
set_comment(is_contextual
? "[ DeferredReferenceGetNamedValue (contextual)"
: "[ DeferredReferenceGetNamedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
void set_is_dont_delete(bool value) {
ASSERT(is_contextual_);
is_dont_delete_ = value;
}
private:
Label patch_site_;
Register dst_;
Register receiver_;
Handle<String> name_;
bool is_contextual_;
bool is_dont_delete_;
};
void DeferredReferenceGetNamedValue::Generate() {
if (!receiver_.is(eax)) {
__ mov(eax, receiver_);
}
__ Set(ecx, Immediate(name_));
Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
RelocInfo::Mode mode = is_contextual_
? RelocInfo::CODE_TARGET_CONTEXT
: RelocInfo::CODE_TARGET;
__ call(ic, mode);
// The call must be followed by:
// - a test eax instruction to indicate that the inobject property
// case was inlined.
// - a mov ecx or mov edx instruction to indicate that the
// contextual property load 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.
if (is_contextual_) {
masm_->mov(is_dont_delete_ ? edx : ecx, -delta_to_patch_site);
__ IncrementCounter(&Counters::named_load_global_inline_miss, 1);
if (is_dont_delete_) {
__ IncrementCounter(&Counters::dont_delete_hint_miss, 1);
}
} else {
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,
Register scratch)
: value_(value),
key_(key),
receiver_(receiver),
scratch_(scratch) {
set_comment("[ DeferredReferenceSetKeyedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Register value_;
Register key_;
Register receiver_;
Register scratch_;
Label patch_site_;
};
void DeferredReferenceSetKeyedValue::Generate() {
__ IncrementCounter(&Counters::keyed_store_inline_miss, 1);
// Move value_ to eax, key_ to ecx, and receiver_ to edx.
Register old_value = value_;
// First, move value to eax.
if (!value_.is(eax)) {
if (key_.is(eax)) {
// Move key_ out of eax, preferably to ecx.
if (!value_.is(ecx) && !receiver_.is(ecx)) {
__ mov(ecx, key_);
key_ = ecx;
} else {
__ mov(scratch_, key_);
key_ = scratch_;
}
}
if (receiver_.is(eax)) {
// Move receiver_ out of eax, preferably to edx.
if (!value_.is(edx) && !key_.is(edx)) {
__ mov(edx, receiver_);
receiver_ = edx;
} else {
// Both moves to scratch are from eax, also, no valid path hits both.
__ mov(scratch_, receiver_);
receiver_ = scratch_;
}
}
__ mov(eax, value_);
value_ = eax;
}
// Now value_ is in eax. Move the other two to the right positions.
// We do not update the variables key_ and receiver_ to ecx and edx.
if (key_.is(ecx)) {
if (!receiver_.is(edx)) {
__ mov(edx, receiver_);
}
} else if (key_.is(edx)) {
if (receiver_.is(ecx)) {
__ xchg(edx, ecx);
} else {
__ mov(ecx, key_);
if (!receiver_.is(edx)) {
__ mov(edx, receiver_);
}
}
} else { // Key is not in edx or ecx.
if (!receiver_.is(edx)) {
__ mov(edx, receiver_);
}
__ mov(ecx, key_);
}
// 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) register.
if (!old_value.is(eax)) __ mov(old_value, eax);
}
Result CodeGenerator::EmitNamedLoad(Handle<String> name, bool is_contextual) {
#ifdef DEBUG
int original_height = frame()->height();
#endif
bool contextual_load_in_builtin =
is_contextual &&
(Bootstrapper::IsActive() ||
(!info_->closure().is_null() && info_->closure()->IsBuiltin()));
Result result;
// Do not inline in the global code or when not in loop.
if (scope()->is_global_scope() ||
loop_nesting() == 0 ||
contextual_load_in_builtin) {
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 property load.
Comment cmnt(masm(), is_contextual
? "[ Inlined contextual property load"
: "[ 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,
is_contextual);
if (!is_contextual) {
// 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 actual load must be
// statically known.
ASSERT(masm()->SizeOfCodeGeneratedSince(deferred->patch_site()) ==
LoadIC::kOffsetToLoadInstruction);
if (is_contextual) {
// Load the (initialy invalid) cell and get its value.
masm()->mov(result.reg(), Factory::null_value());
if (FLAG_debug_code) {
__ cmp(FieldOperand(result.reg(), HeapObject::kMapOffset),
Factory::global_property_cell_map());
__ Assert(equal, "Uninitialized inlined contextual load");
}
__ mov(result.reg(),
FieldOperand(result.reg(), JSGlobalPropertyCell::kValueOffset));
bool is_dont_delete = false;
if (!info_->closure().is_null()) {
// When doing lazy compilation we can check if the global cell
// already exists and use its "don't delete" status as a hint.
AssertNoAllocation no_gc;
v8::internal::GlobalObject* global_object =
info_->closure()->context()->global();
LookupResult lookup;
global_object->LocalLookupRealNamedProperty(*name, &lookup);
if (lookup.IsProperty() && lookup.type() == NORMAL) {
ASSERT(lookup.holder() == global_object);
ASSERT(global_object->property_dictionary()->ValueAt(
lookup.GetDictionaryEntry())->IsJSGlobalPropertyCell());
is_dont_delete = lookup.IsDontDelete();
}
}
deferred->set_is_dont_delete(is_dont_delete);
if (!is_dont_delete) {
__ cmp(result.reg(), Factory::the_hole_value());
deferred->Branch(equal);
} else if (FLAG_debug_code) {
__ cmp(result.reg(), Factory::the_hole_value());
__ Check(not_equal, "DontDelete cells can't contain the hole");
}
__ IncrementCounter(&Counters::named_load_global_inline, 1);
if (is_dont_delete) {
__ IncrementCounter(&Counters::dont_delete_hint_hit, 1);
}
} else {
// 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;
if (is_contextual || scope()->is_global_scope() || loop_nesting() == 0) {
result = frame()->CallStoreIC(name, is_contextual, strict_mode_flag());
// 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 in-object property case.
JumpTarget slow, done;
Label patch_site;
// Get the value and receiver from the stack.
Result value = frame()->Pop();
value.ToRegister();
Result receiver = frame()->Pop();
receiver.ToRegister();
// Allocate result register.
result = allocator()->Allocate();
ASSERT(result.is_valid() && receiver.is_valid() && value.is_valid());
// Check that the receiver is a heap object.
__ test(receiver.reg(), Immediate(kSmiTagMask));
slow.Branch(zero, &value, &receiver);
// 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.
__ bind(&patch_site);
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.
slow.Branch(not_equal, &value, &receiver);
// The delta from the patch label to the store offset must be
// statically known.
ASSERT(masm()->SizeOfCodeGeneratedSince(&patch_site) ==
StoreIC::kOffsetToStoreInstruction);
// 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;
__ mov(FieldOperand(receiver.reg(), offset), value.reg());
__ mov(result.reg(), Operand(value.reg()));
// Allocate scratch register for write barrier.
Result scratch = allocator()->Allocate();
ASSERT(scratch.is_valid());
// The write barrier clobbers all input registers, so spill the
// receiver and the value.
frame_->Spill(receiver.reg());
frame_->Spill(value.reg());
// If the receiver and the value share a register allocate a new
// register for the receiver.
if (receiver.reg().is(value.reg())) {
receiver = allocator()->Allocate();
ASSERT(receiver.is_valid());
__ mov(receiver.reg(), Operand(value.reg()));
}
// Update the write barrier. To save instructions in the inlined
// version we do not filter smis.
Label skip_write_barrier;
__ InNewSpace(receiver.reg(), value.reg(), equal, &skip_write_barrier);
int delta_to_record_write = masm_->SizeOfCodeGeneratedSince(&patch_site);
__ lea(scratch.reg(), Operand(receiver.reg(), offset));
__ RecordWriteHelper(receiver.reg(), scratch.reg(), value.reg());
if (FLAG_debug_code) {
__ mov(receiver.reg(), Immediate(BitCast<int32_t>(kZapValue)));
__ mov(value.reg(), Immediate(BitCast<int32_t>(kZapValue)));
__ mov(scratch.reg(), Immediate(BitCast<int32_t>(kZapValue)));
}
__ bind(&skip_write_barrier);
value.Unuse();
scratch.Unuse();
receiver.Unuse();
done.Jump(&result);
slow.Bind(&value, &receiver);
frame()->Push(&receiver);
frame()->Push(&value);
result = frame()->CallStoreIC(name, is_contextual, strict_mode_flag());
// Encode the offset to the map check instruction and the offset
// to the write barrier store address computation in a test eax
// instruction.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(&patch_site);
__ test(eax,
Immediate((delta_to_record_write << 16) | delta_to_patch_site));
done.Bind(&result);
}
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");
// 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());
Result key = frame_->Pop();
Result receiver = frame_->Pop();
key.ToRegister();
receiver.ToRegister();
// If key and receiver are shared registers on the frame, their values will
// be automatically saved and restored when going to deferred code.
// The result is in elements, which is guaranteed non-shared.
DeferredReferenceGetKeyedValue* deferred =
new DeferredReferenceGetKeyedValue(elements.reg(),
receiver.reg(),
key.reg());
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
// Check that the receiver has the expected map.
// 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.
if (!key.is_smi()) {
__ test(key.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(key.reg());
}
// Get the elements array from the receiver.
__ mov(elements.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
__ AssertFastElements(elements.reg());
// Check that the key is within bounds.
__ cmp(key.reg(),
FieldOperand(elements.reg(), FixedArray::kLengthOffset));
deferred->Branch(above_equal);
// Load and check that the result is not the hole.
// Key holds a smi.
STATIC_ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ mov(elements.reg(),
FieldOperand(elements.reg(),
key.reg(),
times_2,
FixedArray::kHeaderSize));
result = elements;
__ 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());
Result tmp2 = allocator_->Allocate();
ASSERT(tmp2.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(),
tmp.reg());
// Check that the receiver is not a smi.
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
// Check that the key is a smi.
if (!key.is_smi()) {
__ test(key.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
} else {
if (FLAG_debug_code) __ AbortIfNotSmi(key.reg());
}
// Check that the receiver is a JSArray.
__ CmpObjectType(receiver.reg(), JS_ARRAY_TYPE, tmp.reg());
deferred->Branch(not_equal);
// Check that the key is within bounds. Both the key and the length of
// the JSArray are smis. Use unsigned comparison to handle negative keys.
__ cmp(key.reg(),
FieldOperand(receiver.reg(), JSArray::kLengthOffset));
deferred->Branch(above_equal);
// Get the elements array from the receiver and check that it is not a
// dictionary.
__ mov(tmp.reg(),
FieldOperand(receiver.reg(), JSArray::kElementsOffset));
// Check whether it is possible to omit the write barrier. If the elements
// array is in new space or the value written is a smi we can safely update
// the elements array without write barrier.
Label in_new_space;
__ InNewSpace(tmp.reg(), tmp2.reg(), equal, &in_new_space);
if (!value_is_constant) {
__ test(result.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
}
__ bind(&in_new_space);
// 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(FixedArrayElementOperand(tmp.reg(), key.reg()), 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();
}
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()->AsSlot();
ASSERT(slot != NULL);
cgen_->LoadFromSlotCheckForArguments(slot, NOT_INSIDE_TYPEOF);
if (!persist_after_get_) set_unloaded();
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()->AsSlot();
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()->AsSlot();
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();
}
}
#undef __
#define __ masm.
static void MemCopyWrapper(void* dest, const void* src, size_t size) {
memcpy(dest, src, size);
}
MemCopyFunction CreateMemCopyFunction() {
HandleScope scope;
MacroAssembler masm(NULL, 1 * KB);
// Generated code is put into a fixed, unmovable, buffer, and not into
// the V8 heap. We can't, and don't, refer to any relocatable addresses
// (e.g. the JavaScript nan-object).
// 32-bit C declaration function calls pass arguments on stack.
// Stack layout:
// esp[12]: Third argument, size.
// esp[8]: Second argument, source pointer.
// esp[4]: First argument, destination pointer.
// esp[0]: return address
const int kDestinationOffset = 1 * kPointerSize;
const int kSourceOffset = 2 * kPointerSize;
const int kSizeOffset = 3 * kPointerSize;
int stack_offset = 0; // Update if we change the stack height.
if (FLAG_debug_code) {
__ cmp(Operand(esp, kSizeOffset + stack_offset),
Immediate(kMinComplexMemCopy));
Label ok;
__ j(greater_equal, &ok);
__ int3();
__ bind(&ok);
}
if (CpuFeatures::IsSupported(SSE2)) {
CpuFeatures::Scope enable(SSE2);
__ push(edi);
__ push(esi);
stack_offset += 2 * kPointerSize;
Register dst = edi;
Register src = esi;
Register count = ecx;
__ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
__ mov(src, Operand(esp, stack_offset + kSourceOffset));
__ mov(count, Operand(esp, stack_offset + kSizeOffset));
__ movdqu(xmm0, Operand(src, 0));
__ movdqu(Operand(dst, 0), xmm0);
__ mov(edx, dst);
__ and_(edx, 0xF);
__ neg(edx);
__ add(Operand(edx), Immediate(16));
__ add(dst, Operand(edx));
__ add(src, Operand(edx));
__ sub(Operand(count), edx);
// edi is now aligned. Check if esi is also aligned.
Label unaligned_source;
__ test(Operand(src), Immediate(0x0F));
__ j(not_zero, &unaligned_source);
{
__ IncrementCounter(&Counters::memcopy_aligned, 1);
// Copy loop for aligned source and destination.
__ mov(edx, count);
Register loop_count = ecx;
Register count = edx;
__ shr(loop_count, 5);
{
// Main copy loop.
Label loop;
__ bind(&loop);
__ prefetch(Operand(src, 0x20), 1);
__ movdqa(xmm0, Operand(src, 0x00));
__ movdqa(xmm1, Operand(src, 0x10));
__ add(Operand(src), Immediate(0x20));
__ movdqa(Operand(dst, 0x00), xmm0);
__ movdqa(Operand(dst, 0x10), xmm1);
__ add(Operand(dst), Immediate(0x20));
__ dec(loop_count);
__ j(not_zero, &loop);
}
// At most 31 bytes to copy.
Label move_less_16;
__ test(Operand(count), Immediate(0x10));
__ j(zero, &move_less_16);
__ movdqa(xmm0, Operand(src, 0));
__ add(Operand(src), Immediate(0x10));
__ movdqa(Operand(dst, 0), xmm0);
__ add(Operand(dst), Immediate(0x10));
__ bind(&move_less_16);
// At most 15 bytes to copy. Copy 16 bytes at end of string.
__ and_(count, 0xF);
__ movdqu(xmm0, Operand(src, count, times_1, -0x10));
__ movdqu(Operand(dst, count, times_1, -0x10), xmm0);
__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
__ pop(esi);
__ pop(edi);
__ ret(0);
}
__ Align(16);
{
// Copy loop for unaligned source and aligned destination.
// If source is not aligned, we can't read it as efficiently.
__ bind(&unaligned_source);
__ IncrementCounter(&Counters::memcopy_unaligned, 1);
__ mov(edx, ecx);
Register loop_count = ecx;
Register count = edx;
__ shr(loop_count, 5);
{
// Main copy loop
Label loop;
__ bind(&loop);
__ prefetch(Operand(src, 0x20), 1);
__ movdqu(xmm0, Operand(src, 0x00));
__ movdqu(xmm1, Operand(src, 0x10));
__ add(Operand(src), Immediate(0x20));
__ movdqa(Operand(dst, 0x00), xmm0);
__ movdqa(Operand(dst, 0x10), xmm1);
__ add(Operand(dst), Immediate(0x20));
__ dec(loop_count);
__ j(not_zero, &loop);
}
// At most 31 bytes to copy.
Label move_less_16;
__ test(Operand(count), Immediate(0x10));
__ j(zero, &move_less_16);
__ movdqu(xmm0, Operand(src, 0));
__ add(Operand(src), Immediate(0x10));
__ movdqa(Operand(dst, 0), xmm0);
__ add(Operand(dst), Immediate(0x10));
__ bind(&move_less_16);
// At most 15 bytes to copy. Copy 16 bytes at end of string.
__ and_(count, 0x0F);
__ movdqu(xmm0, Operand(src, count, times_1, -0x10));
__ movdqu(Operand(dst, count, times_1, -0x10), xmm0);
__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
__ pop(esi);
__ pop(edi);
__ ret(0);
}
} else {
__ IncrementCounter(&Counters::memcopy_noxmm, 1);
// SSE2 not supported. Unlikely to happen in practice.
__ push(edi);
__ push(esi);
stack_offset += 2 * kPointerSize;
__ cld();
Register dst = edi;
Register src = esi;
Register count = ecx;
__ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
__ mov(src, Operand(esp, stack_offset + kSourceOffset));
__ mov(count, Operand(esp, stack_offset + kSizeOffset));
// Copy the first word.
__ mov(eax, Operand(src, 0));
__ mov(Operand(dst, 0), eax);
// Increment src,dstso that dst is aligned.
__ mov(edx, dst);
__ and_(edx, 0x03);
__ neg(edx);
__ add(Operand(edx), Immediate(4)); // edx = 4 - (dst & 3)
__ add(dst, Operand(edx));
__ add(src, Operand(edx));
__ sub(Operand(count), edx);
// edi is now aligned, ecx holds number of remaning bytes to copy.
__ mov(edx, count);
count = edx;
__ shr(ecx, 2); // Make word count instead of byte count.
__ rep_movs();
// At most 3 bytes left to copy. Copy 4 bytes at end of string.
__ and_(count, 3);
__ mov(eax, Operand(src, count, times_1, -4));
__ mov(Operand(dst, count, times_1, -4), eax);
__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
__ pop(esi);
__ pop(edi);
__ ret(0);
}
CodeDesc desc;
masm.GetCode(&desc);
ASSERT(desc.reloc_size == 0);
// Copy the generated code into an executable chunk and return a pointer
// to the first instruction in it as a C++ function pointer.
LargeObjectChunk* chunk = LargeObjectChunk::New(desc.instr_size, EXECUTABLE);
if (chunk == NULL) return &MemCopyWrapper;
memcpy(chunk->GetStartAddress(), desc.buffer, desc.instr_size);
CPU::FlushICache(chunk->GetStartAddress(), desc.instr_size);
return FUNCTION_CAST<MemCopyFunction>(chunk->GetStartAddress());
}
#undef __
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_IA32