// Copyright 2006-2009 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "v8.h"
#include "bootstrapper.h"
#include "codegen-inl.h"
#include "debug.h"
#include "ic-inl.h"
#include "parser.h"
#include "register-allocator-inl.h"
#include "runtime.h"
#include "scopes.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm_)
// -------------------------------------------------------------------------
// Platform-specific DeferredCode functions.
void DeferredCode::SaveRegisters() {
for (int i = 0; i < RegisterAllocator::kNumRegisters; i++) {
int action = registers_[i];
if (action == kPush) {
__ push(RegisterAllocator::ToRegister(i));
} else if (action != kIgnore && (action & kSyncedFlag) == 0) {
__ mov(Operand(ebp, action), RegisterAllocator::ToRegister(i));
}
}
}
void DeferredCode::RestoreRegisters() {
// Restore registers in reverse order due to the stack.
for (int i = RegisterAllocator::kNumRegisters - 1; i >= 0; i--) {
int action = registers_[i];
if (action == kPush) {
__ pop(RegisterAllocator::ToRegister(i));
} else if (action != kIgnore) {
action &= ~kSyncedFlag;
__ mov(RegisterAllocator::ToRegister(i), Operand(ebp, action));
}
}
}
// -------------------------------------------------------------------------
// CodeGenState implementation.
CodeGenState::CodeGenState(CodeGenerator* owner)
: owner_(owner),
typeof_state_(NOT_INSIDE_TYPEOF),
destination_(NULL),
previous_(NULL) {
owner_->set_state(this);
}
CodeGenState::CodeGenState(CodeGenerator* owner,
TypeofState typeof_state,
ControlDestination* destination)
: owner_(owner),
typeof_state_(typeof_state),
destination_(destination),
previous_(owner->state()) {
owner_->set_state(this);
}
CodeGenState::~CodeGenState() {
ASSERT(owner_->state() == this);
owner_->set_state(previous_);
}
// -------------------------------------------------------------------------
// CodeGenerator implementation
CodeGenerator::CodeGenerator(int buffer_size,
Handle<Script> script,
bool is_eval)
: is_eval_(is_eval),
script_(script),
deferred_(8),
masm_(new MacroAssembler(NULL, buffer_size)),
scope_(NULL),
frame_(NULL),
allocator_(NULL),
state_(NULL),
loop_nesting_(0),
function_return_is_shadowed_(false),
in_spilled_code_(false) {
}
// Calling conventions:
// ebp: caller's frame pointer
// esp: stack pointer
// edi: called JS function
// esi: callee's context
void CodeGenerator::GenCode(FunctionLiteral* fun) {
// Record the position for debugging purposes.
CodeForFunctionPosition(fun);
ZoneList<Statement*>* body = fun->body();
// Initialize state.
ASSERT(scope_ == NULL);
scope_ = fun->scope();
ASSERT(allocator_ == NULL);
RegisterAllocator register_allocator(this);
allocator_ = ®ister_allocator;
ASSERT(frame_ == NULL);
frame_ = new VirtualFrame();
set_in_spilled_code(false);
// Adjust for function-level loop nesting.
loop_nesting_ += fun->loop_nesting();
JumpTarget::set_compiling_deferred_code(false);
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
fun->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
frame_->SpillAll();
__ int3();
}
#endif
// New scope to get automatic timing calculation.
{ // NOLINT
HistogramTimerScope codegen_timer(&Counters::code_generation);
CodeGenState state(this);
// Entry:
// Stack: receiver, arguments, return address.
// ebp: caller's frame pointer
// esp: stack pointer
// edi: called JS function
// esi: callee's context
allocator_->Initialize();
frame_->Enter();
// Allocate space for locals and initialize them.
frame_->AllocateStackSlots();
// 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;
// Allocate the local context if needed.
if (scope_->num_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 = frame_->CallRuntime(Runtime::kNewContext, 1);
// Update context local.
frame_->SaveContextRegister();
// Verify that the runtime call result and esi agree.
if (FLAG_debug_code) {
__ cmp(context.reg(), Operand(esi));
__ Assert(equal, "Runtime::NewContext should end up in esi");
}
}
// TODO(1241774): Improve this code:
// 1) only needed if we have a context
// 2) no need to recompute context ptr every single time
// 3) don't copy parameter operand code from SlotOperand!
{
Comment cmnt2(masm_, "[ copy context parameters into .context");
// Note that iteration order is relevant here! If we have the same
// parameter twice (e.g., function (x, y, x)), and that parameter
// needs to be copied into the context, it must be the last argument
// passed to the parameter that needs to be copied. This is a rare
// case so we don't check for it, instead we rely on the copying
// order: such a parameter is copied repeatedly into the same
// context location and thus the last value is what is seen inside
// the function.
for (int i = 0; i < scope_->num_parameters(); i++) {
Variable* par = scope_->parameter(i);
Slot* slot = par->slot();
if (slot != NULL && slot->type() == Slot::CONTEXT) {
// The use of SlotOperand below is safe in unspilled code
// because the slot is guaranteed to be a context slot.
//
// There are no parameters in the global scope.
ASSERT(!scope_->is_global_scope());
frame_->PushParameterAt(i);
Result value = frame_->Pop();
value.ToRegister();
// SlotOperand loads context.reg() with the context object
// stored to, used below in RecordWrite.
Result context = allocator_->Allocate();
ASSERT(context.is_valid());
__ mov(SlotOperand(slot, context.reg()), value.reg());
int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
frame_->Spill(context.reg());
frame_->Spill(value.reg());
__ RecordWrite(context.reg(), offset, value.reg(), scratch.reg());
}
}
}
// Store the arguments object. This must happen after context
// initialization because the arguments object may be stored in
// the context.
if (ArgumentsMode() != NO_ARGUMENTS_ALLOCATION) {
StoreArgumentsObject(true);
}
// 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(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(fun);
frame_->PrepareForReturn();
Result undefined(Factory::undefined_value());
if (function_return_.is_bound()) {
function_return_.Jump(&undefined);
} else {
function_return_.Bind(&undefined);
GenerateReturnSequence(&undefined);
}
} else if (function_return_.is_linked()) {
// If the return target has dangling jumps to it, then we have not
// yet generated the return sequence. This can happen when (a)
// control does not flow off the end of the body so we did not
// compile an artificial return statement just above, and (b) there
// are return statements in the body but (c) they are all shadowed.
Result return_value;
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}
}
// Adjust for function-level loop nesting.
loop_nesting_ -= fun->loop_nesting();
// Code generation state must be reset.
ASSERT(state_ == NULL);
ASSERT(loop_nesting() == 0);
ASSERT(!function_return_is_shadowed_);
function_return_.Unuse();
DeleteFrame();
// Process any deferred code using the register allocator.
if (!HasStackOverflow()) {
HistogramTimerScope deferred_timer(&Counters::deferred_code_generation);
JumpTarget::set_compiling_deferred_code(true);
ProcessDeferred();
JumpTarget::set_compiling_deferred_code(false);
}
// There is no need to delete the register allocator, it is a
// stack-allocated local.
allocator_ = NULL;
scope_ = NULL;
}
Operand CodeGenerator::SlotOperand(Slot* slot, Register tmp) {
// Currently, this assertion will fail if we try to assign to
// a constant variable that is constant because it is read-only
// (such as the variable referring to a named function expression).
// We need to implement assignments to read-only variables.
// Ideally, we should do this during AST generation (by converting
// such assignments into expression statements); however, in general
// we may not be able to make the decision until past AST generation,
// that is when the entire program is known.
ASSERT(slot != NULL);
int index = slot->index();
switch (slot->type()) {
case Slot::PARAMETER:
return frame_->ParameterAt(index);
case Slot::LOCAL:
return frame_->LocalAt(index);
case Slot::CONTEXT: {
// Follow the context chain if necessary.
ASSERT(!tmp.is(esi)); // do not overwrite context register
Register context = esi;
int chain_length = scope()->ContextChainLength(slot->var()->scope());
for (int i = 0; i < chain_length; i++) {
// Load the closure.
// (All contexts, even 'with' contexts, have a closure,
// and it is the same for all contexts inside a function.
// There is no need to go to the function context first.)
__ mov(tmp, ContextOperand(context, Context::CLOSURE_INDEX));
// Load the function context (which is the incoming, outer context).
__ mov(tmp, FieldOperand(tmp, JSFunction::kContextOffset));
context = tmp;
}
// We may have a 'with' context now. Get the function context.
// (In fact this mov may never be the needed, since the scope analysis
// may not permit a direct context access in this case and thus we are
// always at a function context. However it is safe to dereference be-
// cause the function context of a function context is itself. Before
// deleting this mov we should try to create a counter-example first,
// though...)
__ mov(tmp, ContextOperand(context, Context::FCONTEXT_INDEX));
return ContextOperand(tmp, index);
}
default:
UNREACHABLE();
return Operand(eax);
}
}
Operand CodeGenerator::ContextSlotOperandCheckExtensions(Slot* slot,
Result tmp,
JumpTarget* slow) {
ASSERT(slot->type() == Slot::CONTEXT);
ASSERT(tmp.is_register());
Register context = esi;
for (Scope* s = scope(); s != slot->var()->scope(); s = s->outer_scope()) {
if (s->num_heap_slots() > 0) {
if (s->calls_eval()) {
// Check that extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
Immediate(0));
slow->Branch(not_equal, not_taken);
}
__ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
context = tmp.reg();
}
}
// Check that last extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX), Immediate(0));
slow->Branch(not_equal, not_taken);
__ mov(tmp.reg(), ContextOperand(context, Context::FCONTEXT_INDEX));
return ContextOperand(tmp.reg(), slot->index());
}
// Emit code to load the value of an expression to the top of the
// frame. If the expression is boolean-valued it may be compiled (or
// partially compiled) into control flow to the control destination.
// If force_control is true, control flow is forced.
void CodeGenerator::LoadCondition(Expression* x,
TypeofState typeof_state,
ControlDestination* dest,
bool force_control) {
ASSERT(!in_spilled_code());
int original_height = frame_->height();
{ CodeGenState new_state(this, typeof_state, dest);
Visit(x);
// If we hit a stack overflow, we may not have actually visited
// the expression. In that case, we ensure that we have a
// valid-looking frame state because we will continue to generate
// code as we unwind the C++ stack.
//
// It's possible to have both a stack overflow and a valid frame
// state (eg, a subexpression overflowed, visiting it returned
// with a dummied frame state, and visiting this expression
// returned with a normal-looking state).
if (HasStackOverflow() &&
!dest->is_used() &&
frame_->height() == original_height) {
dest->Goto(true);
}
}
if (force_control && !dest->is_used()) {
// Convert the TOS value into flow to the control destination.
ToBoolean(dest);
}
ASSERT(!(force_control && !dest->is_used()));
ASSERT(dest->is_used() || frame_->height() == original_height + 1);
}
void CodeGenerator::LoadAndSpill(Expression* expression,
TypeofState typeof_state) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
Load(expression, typeof_state);
frame_->SpillAll();
set_in_spilled_code(true);
}
void CodeGenerator::Load(Expression* x, TypeofState typeof_state) {
#ifdef DEBUG
int original_height = frame_->height();
#endif
ASSERT(!in_spilled_code());
JumpTarget true_target;
JumpTarget false_target;
ControlDestination dest(&true_target, &false_target, true);
LoadCondition(x, typeof_state, &dest, false);
if (dest.false_was_fall_through()) {
// The false target was just bound.
JumpTarget loaded;
frame_->Push(Factory::false_value());
// There may be dangling jumps to the true target.
if (true_target.is_linked()) {
loaded.Jump();
true_target.Bind();
frame_->Push(Factory::true_value());
loaded.Bind();
}
} else if (dest.is_used()) {
// There is true, and possibly false, control flow (with true as
// the fall through).
JumpTarget loaded;
frame_->Push(Factory::true_value());
if (false_target.is_linked()) {
loaded.Jump();
false_target.Bind();
frame_->Push(Factory::false_value());
loaded.Bind();
}
} else {
// We have a valid value on top of the frame, but we still may
// have dangling jumps to the true and false targets from nested
// subexpressions (eg, the left subexpressions of the
// short-circuited boolean operators).
ASSERT(has_valid_frame());
if (true_target.is_linked() || false_target.is_linked()) {
JumpTarget loaded;
loaded.Jump(); // Don't lose the current TOS.
if (true_target.is_linked()) {
true_target.Bind();
frame_->Push(Factory::true_value());
if (false_target.is_linked()) {
loaded.Jump();
}
}
if (false_target.is_linked()) {
false_target.Bind();
frame_->Push(Factory::false_value());
}
loaded.Bind();
}
}
ASSERT(has_valid_frame());
ASSERT(frame_->height() == original_height + 1);
}
void CodeGenerator::LoadGlobal() {
if (in_spilled_code()) {
frame_->EmitPush(GlobalObject());
} else {
Result temp = allocator_->Allocate();
__ mov(temp.reg(), GlobalObject());
frame_->Push(&temp);
}
}
void CodeGenerator::LoadGlobalReceiver() {
Result temp = allocator_->Allocate();
Register reg = temp.reg();
__ mov(reg, GlobalObject());
__ mov(reg, FieldOperand(reg, GlobalObject::kGlobalReceiverOffset));
frame_->Push(&temp);
}
// TODO(1241834): Get rid of this function in favor of just using Load, now
// that we have the INSIDE_TYPEOF typeof state. => Need to handle global
// variables w/o reference errors elsewhere.
void CodeGenerator::LoadTypeofExpression(Expression* x) {
Variable* variable = x->AsVariableProxy()->AsVariable();
if (variable != NULL && !variable->is_this() && variable->is_global()) {
// NOTE: This is somewhat nasty. We force the compiler to load
// the variable as if through '<global>.<variable>' to make sure we
// do not get reference errors.
Slot global(variable, Slot::CONTEXT, Context::GLOBAL_INDEX);
Literal key(variable->name());
// TODO(1241834): Fetch the position from the variable instead of using
// no position.
Property property(&global, &key, RelocInfo::kNoPosition);
Load(&property);
} else {
Load(x, INSIDE_TYPEOF);
}
}
ArgumentsAllocationMode CodeGenerator::ArgumentsMode() const {
if (scope_->arguments() == NULL) return NO_ARGUMENTS_ALLOCATION;
ASSERT(scope_->arguments_shadow() != NULL);
// We don't want to do lazy arguments allocation for functions that
// have heap-allocated contexts, because it interfers with the
// uninitialized const tracking in the context objects.
return (scope_->num_heap_slots() > 0)
? EAGER_ARGUMENTS_ALLOCATION
: LAZY_ARGUMENTS_ALLOCATION;
}
Result CodeGenerator::StoreArgumentsObject(bool initial) {
ArgumentsAllocationMode mode = ArgumentsMode();
ASSERT(mode != NO_ARGUMENTS_ALLOCATION);
Comment cmnt(masm_, "[ store arguments object");
if (mode == LAZY_ARGUMENTS_ALLOCATION && initial) {
// When using lazy arguments allocation, we store the hole value
// as a sentinel indicating that the arguments object hasn't been
// allocated yet.
frame_->Push(Factory::the_hole_value());
} else {
ArgumentsAccessStub stub(ArgumentsAccessStub::NEW_OBJECT);
frame_->PushFunction();
frame_->PushReceiverSlotAddress();
frame_->Push(Smi::FromInt(scope_->num_parameters()));
Result result = frame_->CallStub(&stub, 3);
frame_->Push(&result);
}
{ Reference shadow_ref(this, scope_->arguments_shadow());
Reference arguments_ref(this, scope_->arguments());
ASSERT(shadow_ref.is_slot() && arguments_ref.is_slot());
// Here we rely on the convenient property that references to slot
// take up zero space in the frame (ie, it doesn't matter that the
// stored value is actually below the reference on the frame).
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(scope_->arguments()->var()->slot(), NOT_INSIDE_TYPEOF);
Result arguments = frame_->Pop();
if (arguments.is_constant()) {
// We have to skip updating the arguments object if it has
// been assigned a proper value.
skip_arguments = !arguments.handle()->IsTheHole();
} else {
__ cmp(Operand(arguments.reg()), Immediate(Factory::the_hole_value()));
arguments.Unuse();
done.Branch(not_equal);
}
}
if (!skip_arguments) {
arguments_ref.SetValue(NOT_CONST_INIT);
if (mode == LAZY_ARGUMENTS_ALLOCATION) done.Bind();
}
shadow_ref.SetValue(NOT_CONST_INIT);
}
return frame_->Pop();
}
Reference::Reference(CodeGenerator* cgen, Expression* expression)
: cgen_(cgen), expression_(expression), type_(ILLEGAL) {
cgen->LoadReference(this);
}
Reference::~Reference() {
cgen_->UnloadReference(this);
}
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());
// We use a named reference if the key is a literal symbol, unless it is
// a string that can be legally parsed as an integer. This is because
// otherwise we will not get into the slow case code that handles [] on
// String objects.
Literal* literal = property->key()->AsLiteral();
uint32_t dummy;
if (literal != NULL &&
literal->handle()->IsSymbol() &&
!String::cast(*(literal->handle()))->AsArrayIndex(&dummy)) {
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()) {
LoadGlobal();
ref->set_type(Reference::NAMED);
} else {
ASSERT(var->slot() != NULL);
ref->set_type(Reference::SLOT);
}
} else {
// Anything else is a runtime error.
Load(e);
frame_->CallRuntime(Runtime::kThrowReferenceError, 1);
}
in_spilled_code_ = was_in_spilled_code;
}
void CodeGenerator::UnloadReference(Reference* ref) {
// Pop a reference from the stack while preserving TOS.
Comment cmnt(masm_, "[ UnloadReference");
frame_->Nip(ref->size());
}
// 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();
// Fast case checks.
// 'false' => false.
__ cmp(value.reg(), Factory::false_value());
dest->false_target()->Branch(equal);
// 'true' => true.
__ cmp(value.reg(), Factory::true_value());
dest->true_target()->Branch(equal);
// 'undefined' => false.
__ cmp(value.reg(), Factory::undefined_value());
dest->false_target()->Branch(equal);
// Smi => false iff zero.
ASSERT(kSmiTag == 0);
__ test(value.reg(), Operand(value.reg()));
dest->false_target()->Branch(zero);
__ test(value.reg(), Immediate(kSmiTagMask));
dest->true_target()->Branch(zero);
// Call the stub for all other cases.
frame_->Push(&value); // Undo the Pop() from above.
ToBooleanStub stub;
Result temp = frame_->CallStub(&stub, 1);
// Convert the result to a condition code.
__ test(temp.reg(), Operand(temp.reg()));
temp.Unuse();
dest->Split(not_equal);
}
class FloatingPointHelper : public AllStatic {
public:
// Code pattern for loading a floating point value. Input value must
// be either a smi or a heap number object (fp value). Requirements:
// operand in register number. Returns operand as floating point number
// on FPU stack.
static void LoadFloatOperand(MacroAssembler* masm, Register number);
// Code pattern for loading floating point values. Input values must
// be either smi or heap number objects (fp values). Requirements:
// operand_1 on TOS+1 , operand_2 on TOS+2; Returns operands as
// floating point numbers on FPU stack.
static void LoadFloatOperands(MacroAssembler* masm, Register scratch);
// Test if operands are smi or number objects (fp). Requirements:
// operand_1 in eax, operand_2 in edx; falls through on float
// operands, jumps to the non_float label otherwise.
static void CheckFloatOperands(MacroAssembler* masm,
Label* non_float,
Register scratch);
// Test if operands are numbers (smi or HeapNumber objects), and load
// them into xmm0 and xmm1 if they are. Jump to label not_numbers if
// either operand is not a number. Operands are in edx and eax.
// Leaves operands unchanged.
static void LoadSse2Operands(MacroAssembler* masm, Label* not_numbers);
};
const char* GenericBinaryOpStub::GetName() {
switch (op_) {
case Token::ADD: return "GenericBinaryOpStub_ADD";
case Token::SUB: return "GenericBinaryOpStub_SUB";
case Token::MUL: return "GenericBinaryOpStub_MUL";
case Token::DIV: return "GenericBinaryOpStub_DIV";
case Token::BIT_OR: return "GenericBinaryOpStub_BIT_OR";
case Token::BIT_AND: return "GenericBinaryOpStub_BIT_AND";
case Token::BIT_XOR: return "GenericBinaryOpStub_BIT_XOR";
case Token::SAR: return "GenericBinaryOpStub_SAR";
case Token::SHL: return "GenericBinaryOpStub_SHL";
case Token::SHR: return "GenericBinaryOpStub_SHR";
default: return "GenericBinaryOpStub";
}
}
// Call the specialized stub for a binary operation.
class DeferredInlineBinaryOperation: public DeferredCode {
public:
DeferredInlineBinaryOperation(Token::Value op,
Register dst,
Register left,
Register right,
OverwriteMode mode)
: op_(op), dst_(dst), left_(left), right_(right), mode_(mode) {
set_comment("[ DeferredInlineBinaryOperation");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Register left_;
Register right_;
OverwriteMode mode_;
};
void DeferredInlineBinaryOperation::Generate() {
GenericBinaryOpStub stub(op_, mode_, NO_SMI_CODE_IN_STUB);
stub.GenerateCall(masm_, left_, right_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
void CodeGenerator::GenericBinaryOperation(Token::Value op,
SmiAnalysis* type,
OverwriteMode overwrite_mode) {
Comment cmnt(masm_, "[ BinaryOperation");
Comment cmnt_token(masm_, Token::String(op));
if (op == Token::COMMA) {
// Simply discard left value.
frame_->Nip(1);
return;
}
// Set the flags based on the operation, type and loop nesting level.
GenericBinaryFlags flags;
switch (op) {
case Token::BIT_OR:
case Token::BIT_AND:
case Token::BIT_XOR:
case Token::SHL:
case Token::SHR:
case Token::SAR:
// 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.
flags = (loop_nesting() > 0)
? NO_SMI_CODE_IN_STUB
: NO_GENERIC_BINARY_FLAGS;
break;
default:
// By default only inline the Smi check code for likely smis if this
// operation is part of a loop.
flags = ((loop_nesting() > 0) && type->IsLikelySmi())
? NO_SMI_CODE_IN_STUB
: NO_GENERIC_BINARY_FLAGS;
break;
}
Result right = frame_->Pop();
Result left = frame_->Pop();
if (op == Token::ADD) {
bool left_is_string = left.is_constant() && left.handle()->IsString();
bool right_is_string = right.is_constant() && right.handle()->IsString();
if (left_is_string || right_is_string) {
frame_->Push(&left);
frame_->Push(&right);
Result answer;
if (left_is_string) {
if (right_is_string) {
// TODO(lrn): if both are constant strings
// -- do a compile time cons, if allocation during codegen is allowed.
answer = frame_->CallRuntime(Runtime::kStringAdd, 2);
} else {
answer =
frame_->InvokeBuiltin(Builtins::STRING_ADD_LEFT, CALL_FUNCTION, 2);
}
} else if (right_is_string) {
answer =
frame_->InvokeBuiltin(Builtins::STRING_ADD_RIGHT, CALL_FUNCTION, 2);
}
frame_->Push(&answer);
return;
}
// Neither operand is known to be a string.
}
bool left_is_smi = left.is_constant() && left.handle()->IsSmi();
bool left_is_non_smi = left.is_constant() && !left.handle()->IsSmi();
bool right_is_smi = right.is_constant() && right.handle()->IsSmi();
bool right_is_non_smi = right.is_constant() && !right.handle()->IsSmi();
bool generate_no_smi_code = false; // No smi code at all, inline or in stub.
if (left_is_smi && right_is_smi) {
// 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;
}
if (left_is_non_smi || right_is_non_smi) {
// Set flag so that we go straight to the slow case, with no smi code.
generate_no_smi_code = true;
} else if (right_is_smi) {
ConstantSmiBinaryOperation(op, &left, right.handle(),
type, false, overwrite_mode);
return;
} else if (left_is_smi) {
ConstantSmiBinaryOperation(op, &right, left.handle(),
type, true, overwrite_mode);
return;
}
if (((flags & NO_SMI_CODE_IN_STUB) != 0) && !generate_no_smi_code) {
LikelySmiBinaryOperation(op, &left, &right, overwrite_mode);
} else {
frame_->Push(&left);
frame_->Push(&right);
// If we know the arguments aren't smis, use the binary operation stub
// that does not check for the fast smi case.
if (generate_no_smi_code) {
flags = NO_SMI_CODE_IN_STUB;
}
GenericBinaryOpStub stub(op, overwrite_mode, flags);
Result answer = frame_->CallStub(&stub, 2);
frame_->Push(&answer);
}
}
bool CodeGenerator::FoldConstantSmis(Token::Value op, int left, int right) {
Object* answer_object = Heap::undefined_value();
switch (op) {
case Token::ADD:
if (Smi::IsValid(left + right)) {
answer_object = Smi::FromInt(left + right);
}
break;
case Token::SUB:
if (Smi::IsValid(left - right)) {
answer_object = Smi::FromInt(left - right);
}
break;
case Token::MUL: {
double answer = static_cast<double>(left) * right;
if (answer >= Smi::kMinValue && answer <= Smi::kMaxValue) {
// If the product is zero and the non-zero factor is negative,
// the spec requires us to return floating point negative zero.
if (answer != 0 || (left >= 0 && right >= 0)) {
answer_object = Smi::FromInt(static_cast<int>(answer));
}
}
}
break;
case Token::DIV:
case Token::MOD:
break;
case Token::BIT_OR:
answer_object = Smi::FromInt(left | right);
break;
case Token::BIT_AND:
answer_object = Smi::FromInt(left & right);
break;
case Token::BIT_XOR:
answer_object = Smi::FromInt(left ^ right);
break;
case Token::SHL: {
int shift_amount = right & 0x1F;
if (Smi::IsValid(left << shift_amount)) {
answer_object = Smi::FromInt(left << shift_amount);
}
break;
}
case Token::SHR: {
int shift_amount = right & 0x1F;
unsigned int unsigned_left = left;
unsigned_left >>= shift_amount;
if (unsigned_left <= static_cast<unsigned int>(Smi::kMaxValue)) {
answer_object = Smi::FromInt(unsigned_left);
}
break;
}
case Token::SAR: {
int shift_amount = right & 0x1F;
unsigned int unsigned_left = left;
if (left < 0) {
// Perform arithmetic shift of a negative number by
// complementing number, logical shifting, complementing again.
unsigned_left = ~unsigned_left;
unsigned_left >>= shift_amount;
unsigned_left = ~unsigned_left;
} else {
unsigned_left >>= shift_amount;
}
ASSERT(Smi::IsValid(unsigned_left)); // Converted to signed.
answer_object = Smi::FromInt(unsigned_left); // Converted to signed.
break;
}
default:
UNREACHABLE();
break;
}
if (answer_object == Heap::undefined_value()) {
return false;
}
frame_->Push(Handle<Object>(answer_object));
return true;
}
// Implements a binary operation using a deferred code object and some
// inline code to operate on smis quickly.
void CodeGenerator::LikelySmiBinaryOperation(Token::Value op,
Result* left,
Result* right,
OverwriteMode overwrite_mode) {
// Special handling of div and mod because they use fixed registers.
if (op == Token::DIV || op == Token::MOD) {
// We need eax as the quotient register, edx as the remainder
// register, neither left nor right in eax or edx, and left copied
// to eax.
Result quotient;
Result remainder;
bool left_is_in_eax = false;
// Step 1: get eax for quotient.
if ((left->is_register() && left->reg().is(eax)) ||
(right->is_register() && right->reg().is(eax))) {
// One or both is in eax. Use a fresh non-edx register for
// them.
Result fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
if (fresh.reg().is(edx)) {
remainder = fresh;
fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
}
if (left->is_register() && left->reg().is(eax)) {
quotient = *left;
*left = fresh;
left_is_in_eax = true;
}
if (right->is_register() && right->reg().is(eax)) {
quotient = *right;
*right = fresh;
}
__ mov(fresh.reg(), eax);
} else {
// Neither left nor right is in eax.
quotient = allocator_->Allocate(eax);
}
ASSERT(quotient.is_register() && quotient.reg().is(eax));
ASSERT(!(left->is_register() && left->reg().is(eax)));
ASSERT(!(right->is_register() && right->reg().is(eax)));
// Step 2: get edx for remainder if necessary.
if (!remainder.is_valid()) {
if ((left->is_register() && left->reg().is(edx)) ||
(right->is_register() && right->reg().is(edx))) {
Result fresh = allocator_->Allocate();
ASSERT(fresh.is_valid());
if (left->is_register() && left->reg().is(edx)) {
remainder = *left;
*left = fresh;
}
if (right->is_register() && right->reg().is(edx)) {
remainder = *right;
*right = fresh;
}
__ mov(fresh.reg(), edx);
} else {
// Neither left nor right is in edx.
remainder = allocator_->Allocate(edx);
}
}
ASSERT(remainder.is_register() && remainder.reg().is(edx));
ASSERT(!(left->is_register() && left->reg().is(edx)));
ASSERT(!(right->is_register() && right->reg().is(edx)));
left->ToRegister();
right->ToRegister();
frame_->Spill(eax);
frame_->Spill(edx);
// Check that left and right are smi tagged.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
(op == Token::DIV) ? eax : edx,
left->reg(),
right->reg(),
overwrite_mode);
if (left->reg().is(right->reg())) {
__ test(left->reg(), Immediate(kSmiTagMask));
} else {
// Use the quotient register as a scratch for the tag check.
if (!left_is_in_eax) __ mov(eax, left->reg());
left_is_in_eax = false; // About to destroy the value in eax.
__ or_(eax, Operand(right->reg()));
ASSERT(kSmiTag == 0); // Adjust test if not the case.
__ test(eax, Immediate(kSmiTagMask));
}
deferred->Branch(not_zero);
if (!left_is_in_eax) __ mov(eax, left->reg());
// Sign extend eax into edx:eax.
__ cdq();
// Check for 0 divisor.
__ test(right->reg(), Operand(right->reg()));
deferred->Branch(zero);
// Divide edx:eax by the right operand.
__ idiv(right->reg());
// Complete the operation.
if (op == Token::DIV) {
// Check for negative zero result. If result is zero, and divisor
// is negative, return a floating point negative zero. The
// virtual frame is unchanged in this block, so local control flow
// can use a Label rather than a JumpTarget.
Label non_zero_result;
__ test(left->reg(), Operand(left->reg()));
__ j(not_zero, &non_zero_result);
__ test(right->reg(), Operand(right->reg()));
deferred->Branch(negative);
__ bind(&non_zero_result);
// Check for the corner case of dividing the most negative smi by
// -1. We cannot use the overflow flag, since it is not set by
// idiv instruction.
ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ cmp(eax, 0x40000000);
deferred->Branch(equal);
// Check that the remainder is zero.
__ test(edx, Operand(edx));
deferred->Branch(not_zero);
// Tag the result and store it in the quotient register.
ASSERT(kSmiTagSize == times_2); // adjust code if not the case
__ lea(eax, Operand(eax, eax, times_1, kSmiTag));
deferred->BindExit();
left->Unuse();
right->Unuse();
frame_->Push("ient);
} else {
ASSERT(op == Token::MOD);
// Check for a negative zero result. If the result is zero, and
// the dividend is negative, return a floating point negative
// zero. The frame is unchanged in this block, so local control
// flow can use a Label rather than a JumpTarget.
Label non_zero_result;
__ test(edx, Operand(edx));
__ j(not_zero, &non_zero_result, taken);
__ test(left->reg(), Operand(left->reg()));
deferred->Branch(negative);
__ bind(&non_zero_result);
deferred->BindExit();
left->Unuse();
right->Unuse();
frame_->Push(&remainder);
}
return;
}
// Special handling of shift operations because they use fixed
// registers.
if (op == Token::SHL || op == Token::SHR || op == Token::SAR) {
// Move left out of ecx if necessary.
if (left->is_register() && left->reg().is(ecx)) {
*left = allocator_->Allocate();
ASSERT(left->is_valid());
__ mov(left->reg(), ecx);
}
right->ToRegister(ecx);
left->ToRegister();
ASSERT(left->is_register() && !left->reg().is(ecx));
ASSERT(right->is_register() && right->reg().is(ecx));
// We will modify right, it must be spilled.
frame_->Spill(ecx);
// Use a fresh answer register to avoid spilling the left operand.
Result answer = allocator_->Allocate();
ASSERT(answer.is_valid());
// Check that both operands are smis using the answer register as a
// temporary.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
answer.reg(),
left->reg(),
ecx,
overwrite_mode);
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(ecx));
__ test(answer.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
// Untag both operands.
__ mov(answer.reg(), left->reg());
__ sar(answer.reg(), kSmiTagSize);
__ sar(ecx, kSmiTagSize);
// Perform the operation.
switch (op) {
case Token::SAR:
__ sar(answer.reg());
// No checks of result necessary
break;
case Token::SHR: {
Label result_ok;
__ shr(answer.reg());
// Check that the *unsigned* result fits in a smi. Neither of
// the two high-order bits can be set:
// * 0x80000000: high bit would be lost when smi tagging.
// * 0x40000000: this number would convert to negative when smi
// tagging.
// These two cases can only happen with shifts by 0 or 1 when
// handed a valid smi. If the answer cannot be represented by a
// smi, restore the left and right arguments, and jump to slow
// case. The low bit of the left argument may be lost, but only
// in a case where it is dropped anyway.
__ test(answer.reg(), Immediate(0xc0000000));
__ j(zero, &result_ok);
ASSERT(kSmiTag == 0);
__ shl(ecx, kSmiTagSize);
deferred->Jump();
__ bind(&result_ok);
break;
}
case Token::SHL: {
Label result_ok;
__ shl(answer.reg());
// Check that the *signed* result fits in a smi.
__ cmp(answer.reg(), 0xc0000000);
__ j(positive, &result_ok);
ASSERT(kSmiTag == 0);
__ shl(ecx, kSmiTagSize);
deferred->Jump();
__ bind(&result_ok);
break;
}
default:
UNREACHABLE();
}
// Smi-tag the result in answer.
ASSERT(kSmiTagSize == 1); // Adjust code if not the case.
__ lea(answer.reg(),
Operand(answer.reg(), answer.reg(), times_1, kSmiTag));
deferred->BindExit();
left->Unuse();
right->Unuse();
frame_->Push(&answer);
return;
}
// Handle the other binary operations.
left->ToRegister();
right->ToRegister();
// A newly allocated register answer is used to hold the answer. The
// registers containing left and right are not modified so they don't
// need to be spilled in the fast case.
Result answer = allocator_->Allocate();
ASSERT(answer.is_valid());
// Perform the smi tag check.
DeferredInlineBinaryOperation* deferred =
new DeferredInlineBinaryOperation(op,
answer.reg(),
left->reg(),
right->reg(),
overwrite_mode);
if (left->reg().is(right->reg())) {
__ test(left->reg(), Immediate(kSmiTagMask));
} else {
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(right->reg()));
ASSERT(kSmiTag == 0); // Adjust test if not the case.
__ test(answer.reg(), Immediate(kSmiTagMask));
}
deferred->Branch(not_zero);
__ mov(answer.reg(), left->reg());
switch (op) {
case Token::ADD:
__ add(answer.reg(), Operand(right->reg())); // Add optimistically.
deferred->Branch(overflow);
break;
case Token::SUB:
__ sub(answer.reg(), Operand(right->reg())); // Subtract optimistically.
deferred->Branch(overflow);
break;
case Token::MUL: {
// If the smi tag is 0 we can just leave the tag on one operand.
ASSERT(kSmiTag == 0); // Adjust code below if not the case.
// Remove smi tag from the left operand (but keep sign).
// Left-hand operand has been copied into answer.
__ sar(answer.reg(), kSmiTagSize);
// Do multiplication of smis, leaving result in answer.
__ imul(answer.reg(), Operand(right->reg()));
// Go slow on overflows.
deferred->Branch(overflow);
// Check for negative zero result. If product is zero, and one
// argument is negative, go to slow case. The frame is unchanged
// in this block, so local control flow can use a Label rather
// than a JumpTarget.
Label non_zero_result;
__ test(answer.reg(), Operand(answer.reg()));
__ j(not_zero, &non_zero_result, taken);
__ mov(answer.reg(), left->reg());
__ or_(answer.reg(), Operand(right->reg()));
deferred->Branch(negative);
__ xor_(answer.reg(), Operand(answer.reg())); // Positive 0 is correct.
__ bind(&non_zero_result);
break;
}
case Token::BIT_OR:
__ or_(answer.reg(), Operand(right->reg()));
break;
case Token::BIT_AND:
__ and_(answer.reg(), Operand(right->reg()));
break;
case Token::BIT_XOR:
__ xor_(answer.reg(), Operand(right->reg()));
break;
default:
UNREACHABLE();
break;
}
deferred->BindExit();
left->Unuse();
right->Unuse();
frame_->Push(&answer);
}
// Call the appropriate binary operation stub to compute src op value
// and leave the result in dst.
class DeferredInlineSmiOperation: public DeferredCode {
public:
DeferredInlineSmiOperation(Token::Value op,
Register dst,
Register src,
Smi* value,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
src_(src),
value_(value),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiOperation");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Register src_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiOperation::Generate() {
// For mod we don't generate all the Smi code inline.
GenericBinaryOpStub stub(
op_,
overwrite_mode_,
(op_ == Token::MOD) ? NO_GENERIC_BINARY_FLAGS : NO_SMI_CODE_IN_STUB);
stub.GenerateCall(masm_, src_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// Call the appropriate binary operation stub to compute value op src
// and leave the result in dst.
class DeferredInlineSmiOperationReversed: public DeferredCode {
public:
DeferredInlineSmiOperationReversed(Token::Value op,
Register dst,
Smi* value,
Register src,
OverwriteMode overwrite_mode)
: op_(op),
dst_(dst),
value_(value),
src_(src),
overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiOperationReversed");
}
virtual void Generate();
private:
Token::Value op_;
Register dst_;
Smi* value_;
Register src_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiOperationReversed::Generate() {
GenericBinaryOpStub igostub(op_, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, value_, src_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of src + value is in dst. It either overflowed or was not
// smi tagged. Undo the speculative addition and call the appropriate
// specialized stub for add. The result is left in dst.
class DeferredInlineSmiAdd: public DeferredCode {
public:
DeferredInlineSmiAdd(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiAdd");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiAdd::Generate() {
// Undo the optimistic add operation and call the shared stub.
__ sub(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, dst_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of value + src is in dst. It either overflowed or was not
// smi tagged. Undo the speculative addition and call the appropriate
// specialized stub for add. The result is left in dst.
class DeferredInlineSmiAddReversed: public DeferredCode {
public:
DeferredInlineSmiAddReversed(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiAddReversed");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiAddReversed::Generate() {
// Undo the optimistic add operation and call the shared stub.
__ sub(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, value_, dst_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The result of src - value is in dst. It either overflowed or was not
// smi tagged. Undo the speculative subtraction and call the
// appropriate specialized stub for subtract. The result is left in
// dst.
class DeferredInlineSmiSub: public DeferredCode {
public:
DeferredInlineSmiSub(Register dst,
Smi* value,
OverwriteMode overwrite_mode)
: dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
set_comment("[ DeferredInlineSmiSub");
}
virtual void Generate();
private:
Register dst_;
Smi* value_;
OverwriteMode overwrite_mode_;
};
void DeferredInlineSmiSub::Generate() {
// Undo the optimistic sub operation and call the shared stub.
__ add(Operand(dst_), Immediate(value_));
GenericBinaryOpStub igostub(Token::SUB, overwrite_mode_, NO_SMI_CODE_IN_STUB);
igostub.GenerateCall(masm_, dst_, value_);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
void CodeGenerator::ConstantSmiBinaryOperation(Token::Value op,
Result* operand,
Handle<Object> value,
SmiAnalysis* type,
bool reversed,
OverwriteMode overwrite_mode) {
// NOTE: This is an attempt to inline (a bit) more of the code for
// some possible smi operations (like + and -) when (at least) one
// of the operands is a constant smi.
// Consumes the argument "operand".
// TODO(199): Optimize some special cases of operations involving a
// smi literal (multiply by 2, shift by 0, etc.).
if (IsUnsafeSmi(value)) {
Result unsafe_operand(value);
if (reversed) {
LikelySmiBinaryOperation(op, &unsafe_operand, operand,
overwrite_mode);
} else {
LikelySmiBinaryOperation(op, operand, &unsafe_operand,
overwrite_mode);
}
ASSERT(!operand->is_valid());
return;
}
// Get the literal value.
Smi* smi_value = Smi::cast(*value);
int int_value = smi_value->value();
switch (op) {
case Token::ADD: {
operand->ToRegister();
frame_->Spill(operand->reg());
// Optimistically add. Call the specialized add stub if the
// result is not a smi or overflows.
DeferredCode* deferred = NULL;
if (reversed) {
deferred = new DeferredInlineSmiAddReversed(operand->reg(),
smi_value,
overwrite_mode);
} else {
deferred = new DeferredInlineSmiAdd(operand->reg(),
smi_value,
overwrite_mode);
}
__ add(Operand(operand->reg()), Immediate(value));
deferred->Branch(overflow);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
frame_->Push(operand);
break;
}
case Token::SUB: {
DeferredCode* deferred = NULL;
Result answer; // Only allocate a new register if reversed.
if (reversed) {
// The reversed case is only hit when the right operand is not a
// constant.
ASSERT(operand->is_register());
answer = allocator()->Allocate();
ASSERT(answer.is_valid());
__ Set(answer.reg(), Immediate(value));
deferred = new DeferredInlineSmiOperationReversed(op,
answer.reg(),
smi_value,
operand->reg(),
overwrite_mode);
__ sub(answer.reg(), Operand(operand->reg()));
} else {
operand->ToRegister();
frame_->Spill(operand->reg());
answer = *operand;
deferred = new DeferredInlineSmiSub(operand->reg(),
smi_value,
overwrite_mode);
__ sub(Operand(operand->reg()), Immediate(value));
}
deferred->Branch(overflow);
__ test(answer.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
operand->Unuse();
frame_->Push(&answer);
break;
}
case Token::SAR:
if (reversed) {
Result constant_operand(value);
LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
if (shift_value > 0) {
__ sar(operand->reg(), shift_value);
__ and_(operand->reg(), ~kSmiTagMask);
}
deferred->BindExit();
frame_->Push(operand);
}
break;
case Token::SHR:
if (reversed) {
Result constant_operand(value);
LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
Result answer = allocator()->Allocate();
ASSERT(answer.is_valid());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
answer.reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
__ mov(answer.reg(), operand->reg());
__ sar(answer.reg(), kSmiTagSize);
__ 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();
ASSERT(kSmiTagSize == times_2); // Adjust the code if not true.
__ lea(answer.reg(),
Operand(answer.reg(), answer.reg(), times_1, kSmiTag));
deferred->BindExit();
frame_->Push(&answer);
}
break;
case Token::SHL:
if (reversed) {
Result constant_operand(value);
LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
// Only the least significant 5 bits of the shift value are used.
// In the slow case, this masking is done inside the runtime call.
int shift_value = int_value & 0x1f;
operand->ToRegister();
if (shift_value == 0) {
// Spill operand so it can be overwritten in the slow case.
frame_->Spill(operand->reg());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
deferred->BindExit();
frame_->Push(operand);
} else {
// Use a fresh temporary for nonzero shift values.
Result answer = allocator()->Allocate();
ASSERT(answer.is_valid());
DeferredInlineSmiOperation* deferred =
new DeferredInlineSmiOperation(op,
answer.reg(),
operand->reg(),
smi_value,
overwrite_mode);
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
__ mov(answer.reg(), operand->reg());
ASSERT(kSmiTag == 0); // adjust code if not the case
// We do no shifts, only the Smi conversion, if shift_value is 1.
if (shift_value > 1) {
__ shl(answer.reg(), shift_value - 1);
}
// Convert int result to Smi, checking that it is in int range.
ASSERT(kSmiTagSize == 1); // adjust code if not the case
__ add(answer.reg(), Operand(answer.reg()));
deferred->Branch(overflow);
deferred->BindExit();
operand->Unuse();
frame_->Push(&answer);
}
}
break;
case Token::BIT_OR:
case Token::BIT_XOR:
case Token::BIT_AND: {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredCode* deferred = NULL;
if (reversed) {
deferred = new DeferredInlineSmiOperationReversed(op,
operand->reg(),
smi_value,
operand->reg(),
overwrite_mode);
} else {
deferred = new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
}
__ test(operand->reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
if (op == Token::BIT_AND) {
__ and_(Operand(operand->reg()), Immediate(value));
} else if (op == Token::BIT_XOR) {
if (int_value != 0) {
__ xor_(Operand(operand->reg()), Immediate(value));
}
} else {
ASSERT(op == Token::BIT_OR);
if (int_value != 0) {
__ or_(Operand(operand->reg()), Immediate(value));
}
}
deferred->BindExit();
frame_->Push(operand);
break;
}
// Generate inline code for mod of powers of 2 and negative powers of 2.
case Token::MOD:
if (!reversed &&
int_value != 0 &&
(IsPowerOf2(int_value) || IsPowerOf2(-int_value))) {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredCode* deferred = new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
// Check for negative or non-Smi left hand side.
__ test(operand->reg(), Immediate(kSmiTagMask | 0x80000000));
deferred->Branch(not_zero);
if (int_value < 0) int_value = -int_value;
if (int_value == 1) {
__ mov(operand->reg(), Immediate(Smi::FromInt(0)));
} else {
__ and_(operand->reg(), (int_value << kSmiTagSize) - 1);
}
deferred->BindExit();
frame_->Push(operand);
break;
}
// Fall through if we did not find a power of 2 on the right hand side!
default: {
Result constant_operand(value);
if (reversed) {
LikelySmiBinaryOperation(op, &constant_operand, operand,
overwrite_mode);
} else {
LikelySmiBinaryOperation(op, operand, &constant_operand,
overwrite_mode);
}
break;
}
}
ASSERT(!operand->is_valid());
}
void CodeGenerator::Comparison(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 =
left_side.is_constant() && left_side.handle()->IsSmi();
bool right_side_constant_smi =
right_side.is_constant() && right_side.handle()->IsSmi();
bool left_side_constant_null =
left_side.is_constant() && left_side.handle()->IsNull();
bool right_side_constant_null =
right_side.is_constant() && right_side.handle()->IsNull();
if (left_side_constant_smi || right_side_constant_smi) {
if (left_side_constant_smi && right_side_constant_smi) {
// Trivial case, comparing two constants.
int left_value = Smi::cast(*left_side.handle())->value();
int right_value = Smi::cast(*right_side.handle())->value();
switch (cc) {
case less:
dest->Goto(left_value < right_value);
break;
case equal:
dest->Goto(left_value == right_value);
break;
case greater_equal:
dest->Goto(left_value >= right_value);
break;
default:
UNREACHABLE();
}
} else { // Only one side is a constant Smi.
// If left side is a constant Smi, reverse the operands.
// Since one side is a constant Smi, conversion order does not matter.
if (left_side_constant_smi) {
Result temp = left_side;
left_side = right_side;
right_side = temp;
cc = ReverseCondition(cc);
// This may reintroduce greater or less_equal as the value of cc.
// CompareStub and the inline code both support all values of cc.
}
// Implement comparison against a constant Smi, inlining the case
// where both sides are Smis.
left_side.ToRegister();
// 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();
Handle<Object> right_val = right_side.handle();
__ test(left_side.reg(), Immediate(kSmiTagMask));
is_smi.Branch(zero, taken);
// Setup and call the compare stub.
CompareStub stub(cc, strict);
Result result = frame_->CallStub(&stub, &left_side, &right_side);
result.ToRegister();
__ cmp(result.reg(), 0);
result.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
is_smi.Bind();
left_side = Result(left_reg);
right_side = Result(right_val);
// Test smi equality and comparison by signed int comparison.
if (IsUnsafeSmi(right_side.handle())) {
right_side.ToRegister();
__ cmp(left_side.reg(), Operand(right_side.reg()));
} else {
__ cmp(Operand(left_side.reg()), Immediate(right_side.handle()));
}
left_side.Unuse();
right_side.Unuse();
dest->Split(cc);
}
} else if (cc == equal &&
(left_side_constant_null || right_side_constant_null)) {
// To make null checks efficient, we check if either the left side or
// the right side is the constant 'null'.
// If so, we optimize the code by inlining a null check instead of
// calling the (very) general runtime routine for checking equality.
Result operand = left_side_constant_null ? right_side : left_side;
right_side.Unuse();
left_side.Unuse();
operand.ToRegister();
__ cmp(operand.reg(), Factory::null_value());
if (strict) {
operand.Unuse();
dest->Split(equal);
} else {
// The 'null' value is only equal to 'undefined' if using non-strict
// comparisons.
dest->true_target()->Branch(equal);
__ cmp(operand.reg(), Factory::undefined_value());
dest->true_target()->Branch(equal);
__ test(operand.reg(), Immediate(kSmiTagMask));
dest->false_target()->Branch(equal);
// It can be an undetectable object.
// Use a scratch register in preference to spilling operand.reg().
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(),
FieldOperand(operand.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(),
FieldOperand(temp.reg(), Map::kBitFieldOffset));
__ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
temp.Unuse();
operand.Unuse();
dest->Split(not_zero);
}
} else { // Neither side is a constant Smi or null.
// If either side is a non-smi constant, skip the smi check.
bool known_non_smi =
(left_side.is_constant() && !left_side.handle()->IsSmi()) ||
(right_side.is_constant() && !right_side.handle()->IsSmi());
left_side.ToRegister();
right_side.ToRegister();
if (known_non_smi) {
// When non-smi, call out to the compare stub.
CompareStub stub(cc, strict);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
} else {
__ cmp(answer.reg(), 0);
}
answer.Unuse();
dest->Split(cc);
} else {
// Here we split control flow to the stub call and inlined cases
// before finally splitting it to the control destination. We use
// a jump target and branching to duplicate the virtual frame at
// the first split. We manually handle the off-frame references
// by reconstituting them on the non-fall-through path.
JumpTarget is_smi;
Register left_reg = left_side.reg();
Register right_reg = right_side.reg();
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), left_side.reg());
__ or_(temp.reg(), Operand(right_side.reg()));
__ test(temp.reg(), Immediate(kSmiTagMask));
temp.Unuse();
is_smi.Branch(zero, taken);
// When non-smi, call out to the compare stub.
CompareStub stub(cc, strict);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
} else {
__ cmp(answer.reg(), 0);
}
answer.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
is_smi.Bind();
left_side = Result(left_reg);
right_side = Result(right_reg);
__ cmp(left_side.reg(), Operand(right_side.reg()));
right_side.Unuse();
left_side.Unuse();
dest->Split(cc);
}
}
}
// Call the function just below TOS on the stack with the given
// arguments. The receiver is the TOS.
void CodeGenerator::CallWithArguments(ZoneList<Expression*>* args,
int position) {
// Push the arguments ("left-to-right") on the stack.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Record the position for debugging purposes.
CodeForSourcePosition(position);
// Use the shared code stub to call the function.
InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
CallFunctionStub call_function(arg_count, in_loop);
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(Property* apply,
Expression* receiver,
VariableProxy* arguments,
int position) {
ASSERT(ArgumentsMode() == LAZY_ARGUMENTS_ALLOCATION);
ASSERT(arguments->IsArguments());
JumpTarget slow, done;
// Load the apply function onto the stack. This will usually
// give us a megamorphic load site. Not super, but it works.
Reference ref(this, apply);
ref.GetValue(NOT_INSIDE_TYPEOF);
ASSERT(ref.type() == Reference::NAMED);
// Load the receiver and the existing arguments object onto the
// expression stack. Avoid allocating the arguments object here.
Load(receiver);
LoadFromSlot(scope_->arguments()->var()->slot(), NOT_INSIDE_TYPEOF);
// Emit the source position information after having loaded the
// receiver and the arguments.
CodeForSourcePosition(position);
// 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();
bool try_lazy = true;
if (probe.is_constant()) {
try_lazy = probe.handle()->IsTheHole();
} else {
__ cmp(Operand(probe.reg()), Immediate(Factory::the_hole_value()));
probe.Unuse();
slow.Branch(not_equal);
}
if (try_lazy) {
JumpTarget build_args;
// Get rid of the arguments object probe.
frame_->Drop();
// Before messing with the execution stack, we sync all
// elements. This is bound to happen anyway because we're
// about to call a function.
frame_->SyncRange(0, frame_->element_count() - 1);
// Check that the receiver really is a JavaScript object.
{ frame_->PushElementAt(0);
Result receiver = frame_->Pop();
receiver.ToRegister();
__ test(receiver.reg(), Immediate(kSmiTagMask));
build_args.Branch(zero);
Result tmp = allocator_->Allocate();
// We allow all JSObjects including JSFunctions. As long as
// JS_FUNCTION_TYPE is the last instance type and it is right
// after LAST_JS_OBJECT_TYPE, we do not have to check the upper
// bound.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
__ CmpObjectType(receiver.reg(), FIRST_JS_OBJECT_TYPE, tmp.reg());
build_args.Branch(less);
}
// Verify that we're invoking Function.prototype.apply.
{ frame_->PushElementAt(1);
Result apply = frame_->Pop();
apply.ToRegister();
__ test(apply.reg(), Immediate(kSmiTagMask));
build_args.Branch(zero);
Result tmp = allocator_->Allocate();
__ CmpObjectType(apply.reg(), JS_FUNCTION_TYPE, tmp.reg());
build_args.Branch(not_equal);
__ mov(tmp.reg(),
FieldOperand(apply.reg(), JSFunction::kSharedFunctionInfoOffset));
Handle<Code> apply_code(Builtins::builtin(Builtins::FunctionApply));
__ cmp(FieldOperand(tmp.reg(), SharedFunctionInfo::kCodeOffset),
Immediate(apply_code));
build_args.Branch(not_equal);
}
// Get the function receiver from the stack. Check that it
// really is a function.
__ mov(edi, Operand(esp, 2 * kPointerSize));
__ test(edi, Immediate(kSmiTagMask));
build_args.Branch(zero);
__ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
build_args.Branch(not_equal);
// 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));
__ shr(eax, kSmiTagSize);
__ mov(ecx, Operand(eax));
__ cmp(eax, kArgumentsLimit);
build_args.Branch(above);
// 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;
__ bind(&loop);
__ test(ecx, Operand(ecx));
__ j(zero, &invoke);
__ push(Operand(edx, ecx, times_4, 1 * kPointerSize));
__ dec(ecx);
__ jmp(&loop);
// Invoke the function. The virtual frame knows about the receiver
// so make sure to forget that explicitly.
__ bind(&invoke);
ParameterCount actual(eax);
__ InvokeFunction(edi, actual, CALL_FUNCTION);
frame_->Forget(1);
Result result = allocator()->Allocate(eax);
frame_->SetElementAt(0, &result);
done.Jump();
// Slow-case: Allocate the arguments object since we know it isn't
// there, and fall-through to the slow-case where we call
// Function.prototype.apply.
build_args.Bind();
Result arguments_object = StoreArgumentsObject(false);
frame_->Push(&arguments_object);
slow.Bind();
}
// Flip the apply function and the function to call on the stack, so
// the function looks like the receiver of the apply call. This way,
// the generic Function.prototype.apply implementation can deal with
// the call like it usually does.
Result a2 = frame_->Pop();
Result a1 = frame_->Pop();
Result ap = frame_->Pop();
Result fn = frame_->Pop();
frame_->Push(&ap);
frame_->Push(&fn);
frame_->Push(&a1);
frame_->Push(&a2);
CallFunctionStub call_function(2, NOT_IN_LOOP);
Result res = frame_->CallStub(&call_function, 3);
frame_->Push(&res);
// All done. Restore context register after call.
if (try_lazy) done.Bind();
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_guard_limit =
ExternalReference::address_of_stack_guard_limit();
__ cmp(esp, Operand::StaticVariable(stack_guard_limit));
deferred->Branch(below);
deferred->BindExit();
}
void CodeGenerator::VisitAndSpill(Statement* statement) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
Visit(statement);
if (frame_ != NULL) {
frame_->SpillAll();
}
set_in_spilled_code(true);
}
void CodeGenerator::VisitStatementsAndSpill(ZoneList<Statement*>* statements) {
ASSERT(in_spilled_code());
set_in_spilled_code(false);
VisitStatements(statements);
if (frame_ != NULL) {
frame_->SpillAll();
}
set_in_spilled_code(true);
}
void CodeGenerator::VisitStatements(ZoneList<Statement*>* statements) {
ASSERT(!in_spilled_code());
for (int i = 0; has_valid_frame() && i < statements->length(); i++) {
Visit(statements->at(i));
}
}
void CodeGenerator::VisitBlock(Block* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ Block");
CodeForStatementPosition(node);
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
VisitStatements(node->statements());
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
node->break_target()->Unuse();
}
void CodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
// Call the runtime to declare the globals. The inevitable call
// will sync frame elements to memory anyway, so we do it eagerly to
// allow us to push the arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi); // The context is the first argument.
frame_->EmitPush(Immediate(pairs));
frame_->EmitPush(Immediate(Smi::FromInt(is_eval() ? 1 : 0)));
Result ignored = frame_->CallRuntime(Runtime::kDeclareGlobals, 3);
// Return value is ignored.
}
void CodeGenerator::VisitDeclaration(Declaration* node) {
Comment cmnt(masm_, "[ Declaration");
Variable* var = node->proxy()->var();
ASSERT(var != NULL); // must have been resolved
Slot* slot = var->slot();
// If it was not possible to allocate the variable at compile time,
// we need to "declare" it at runtime to make sure it actually
// exists in the local context.
if (slot != NULL && slot->type() == Slot::LOOKUP) {
// Variables with a "LOOKUP" slot were introduced as non-locals
// during variable resolution and must have mode DYNAMIC.
ASSERT(var->is_dynamic());
// For now, just do a runtime call. Sync the virtual frame eagerly
// so we can simply push the arguments into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(var->name()));
// Declaration nodes are always introduced in one of two modes.
ASSERT(node->mode() == Variable::VAR || node->mode() == Variable::CONST);
PropertyAttributes attr = node->mode() == Variable::VAR ? NONE : READ_ONLY;
frame_->EmitPush(Immediate(Smi::FromInt(attr)));
// Push initial value, if any.
// Note: For variables we must not push an initial value (such as
// 'undefined') because we may have a (legal) redeclaration and we
// must not destroy the current value.
if (node->mode() == Variable::CONST) {
frame_->EmitPush(Immediate(Factory::the_hole_value()));
} else if (node->fun() != NULL) {
Load(node->fun());
} else {
frame_->EmitPush(Immediate(Smi::FromInt(0))); // no initial value!
}
Result ignored = frame_->CallRuntime(Runtime::kDeclareContextSlot, 4);
// Ignore the return value (declarations are statements).
return;
}
ASSERT(!var->is_global());
// If we have a function or a constant, we need to initialize the variable.
Expression* val = NULL;
if (node->mode() == Variable::CONST) {
val = new Literal(Factory::the_hole_value());
} else {
val = node->fun(); // NULL if we don't have a function
}
if (val != NULL) {
{
// Set the initial value.
Reference target(this, node->proxy());
Load(val);
target.SetValue(NOT_CONST_INIT);
// The reference is removed from the stack (preserving TOS) when
// it goes out of scope.
}
// Get rid of the assigned value (declarations are statements).
frame_->Drop();
}
}
void CodeGenerator::VisitExpressionStatement(ExpressionStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ExpressionStatement");
CodeForStatementPosition(node);
Expression* expression = node->expression();
expression->MarkAsStatement();
Load(expression);
// Remove the lingering expression result from the top of stack.
frame_->Drop();
}
void CodeGenerator::VisitEmptyStatement(EmptyStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "// EmptyStatement");
CodeForStatementPosition(node);
// nothing to do
}
void CodeGenerator::VisitIfStatement(IfStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ IfStatement");
// Generate different code depending on which parts of the if statement
// are present or not.
bool has_then_stm = node->HasThenStatement();
bool has_else_stm = node->HasElseStatement();
CodeForStatementPosition(node);
JumpTarget exit;
if (has_then_stm && has_else_stm) {
JumpTarget then;
JumpTarget else_;
ControlDestination dest(&then, &else_, true);
LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, &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();
if (function_return_is_shadowed_) {
function_return_.Jump(&return_value);
} else {
frame_->PrepareForReturn();
if (function_return_.is_bound()) {
// If the function return label is already bound we reuse the
// code by jumping to the return site.
function_return_.Jump(&return_value);
} else {
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}
}
void CodeGenerator::GenerateReturnSequence(Result* return_value) {
// The return value is a live (but not currently reference counted)
// reference to eax. This is safe because the current frame does not
// contain a reference to eax (it is prepared for the return by spilling
// all registers).
if (FLAG_trace) {
frame_->Push(return_value);
*return_value = frame_->CallRuntime(Runtime::kTraceExit, 1);
}
return_value->ToRegister(eax);
// Add a label for checking the size of the code used for returning.
Label check_exit_codesize;
masm_->bind(&check_exit_codesize);
// Leave the frame and return popping the arguments and the
// receiver.
frame_->Exit();
masm_->ret((scope_->num_parameters() + 1) * kPointerSize);
DeleteFrame();
#ifdef ENABLE_DEBUGGER_SUPPORT
// Check that the size of the code used for returning matches what is
// expected by the debugger.
ASSERT_EQ(Debug::kIa32JSReturnSequenceLength,
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(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()) {
ControlDestination dest(&body, node->break_target(), false);
LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
}
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
break;
}
DecrementLoopNesting();
}
void CodeGenerator::VisitWhileStatement(WhileStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ WhileStatement");
CodeForStatementPosition(node);
// If the condition is always false and has no side effects, we do not
// need to compile anything.
ConditionAnalysis info = AnalyzeCondition(node->cond());
if (info == ALWAYS_FALSE) return;
// Do not duplicate conditions that may have function literal
// subexpressions. This can cause us to compile the function literal
// twice.
bool test_at_bottom = !node->may_have_function_literal();
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
IncrementLoopNesting();
JumpTarget body;
if (test_at_bottom) {
body.set_direction(JumpTarget::BIDIRECTIONAL);
}
// Based on the condition analysis, compile the test as necessary.
switch (info) {
case ALWAYS_TRUE:
// We will not compile the test expression. Label the top of the
// loop with the continue target.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
break;
case DONT_KNOW: {
if (test_at_bottom) {
// Continue is the test at the bottom, no need to label the test
// at the top. The body is a backward target.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
} else {
// Label the test at the top as the continue target. The body
// is a forward-only target.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
}
// Compile the test with the body as the true target and preferred
// fall-through and with the break target as the false target.
ControlDestination dest(&body, node->break_target(), true);
LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, &dest, true);
}
} else {
// If we have chosen not to recompile the test at the bottom,
// jump back to the one at the top.
if (has_valid_frame()) {
node->continue_target()->Jump();
}
}
break;
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
// The break target may be already bound (by the condition), or there
// may not be a valid frame. Bind it only if needed.
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
DecrementLoopNesting();
}
void CodeGenerator::VisitForStatement(ForStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ ForStatement");
CodeForStatementPosition(node);
// Compile the init expression if present.
if (node->init() != NULL) {
Visit(node->init());
}
// If the condition is always false and has no side effects, we do not
// need to compile anything else.
ConditionAnalysis info = AnalyzeCondition(node->cond());
if (info == ALWAYS_FALSE) return;
// Do not duplicate conditions that may have function literal
// subexpressions. This can cause us to compile the function literal
// twice.
bool test_at_bottom = !node->may_have_function_literal();
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
IncrementLoopNesting();
// Target for backward edge if no test at the bottom, otherwise
// unused.
JumpTarget loop(JumpTarget::BIDIRECTIONAL);
// Target for backward edge if there is a test at the bottom,
// otherwise used as target for test at the top.
JumpTarget body;
if (test_at_bottom) {
body.set_direction(JumpTarget::BIDIRECTIONAL);
}
// Based on the condition analysis, compile the test as necessary.
switch (info) {
case ALWAYS_TRUE:
// We will not compile the test expression. Label the top of the
// loop.
if (node->next() == NULL) {
// Use the continue target if there is no update expression.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
} else {
// Otherwise use the backward loop target.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
loop.Bind();
}
break;
case DONT_KNOW: {
if (test_at_bottom) {
// Continue is either the update expression or the test at the
// bottom, no need to label the test at the top.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
} else if (node->next() == NULL) {
// We are not recompiling the test at the bottom and there is no
// update expression.
node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
node->continue_target()->Bind();
} else {
// We are not recompiling the test at the bottom and there is an
// update expression.
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
loop.Bind();
}
// Compile the test with the body as the true target and preferred
// fall-through and with the break target as the false target.
ControlDestination dest(&body, node->break_target(), true);
LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
if (dest.false_was_fall_through()) {
// If we got the break target as fall-through, the test may have
// been unconditionally false (if there are no jumps to the
// body).
if (!body.is_linked()) {
DecrementLoopNesting();
return;
}
// Otherwise, jump around the body on the fall through and then
// bind the body target.
node->break_target()->Unuse();
node->break_target()->Jump();
body.Bind();
}
break;
}
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
CheckStack(); // TODO(1222600): ignore if body contains calls.
Visit(node->body());
// If there is an update expression, compile it if necessary.
if (node->next() != NULL) {
if (node->continue_target()->is_linked()) {
node->continue_target()->Bind();
}
// Control can reach the update by falling out of the body or by a
// continue.
if (has_valid_frame()) {
// Record the source position of the statement as this code which
// is after the code for the body actually belongs to the loop
// statement and not the body.
CodeForStatementPosition(node);
Visit(node->next());
}
}
// Based on the condition analysis, compile the backward jump as
// necessary.
switch (info) {
case ALWAYS_TRUE:
if (has_valid_frame()) {
if (node->next() == NULL) {
node->continue_target()->Jump();
} else {
loop.Jump();
}
}
break;
case DONT_KNOW:
if (test_at_bottom) {
if (node->continue_target()->is_linked()) {
// We can have dangling jumps to the continue target if there
// was no update expression.
node->continue_target()->Bind();
}
// Control can reach the test at the bottom by falling out of
// the body, by a continue in the body, or from the update
// expression.
if (has_valid_frame()) {
// The break target is the fall-through (body is a backward
// jump from here).
ControlDestination dest(&body, node->break_target(), false);
LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
}
} else {
// Otherwise, jump back to the test at the top.
if (has_valid_frame()) {
if (node->next() == NULL) {
node->continue_target()->Jump();
} else {
loop.Jump();
}
}
}
break;
case ALWAYS_FALSE:
UNREACHABLE();
break;
}
// The break target may be already bound (by the condition), or
// there may not be a valid frame. Bind it only if needed.
if (node->break_target()->is_linked()) {
node->break_target()->Bind();
}
DecrementLoopNesting();
}
void CodeGenerator::VisitForInStatement(ForInStatement* node) {
ASSERT(!in_spilled_code());
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ ForInStatement");
CodeForStatementPosition(node);
JumpTarget primitive;
JumpTarget jsobject;
JumpTarget fixed_array;
JumpTarget entry(JumpTarget::BIDIRECTIONAL);
JumpTarget end_del_check;
JumpTarget exit;
// Get the object to enumerate over (converted to JSObject).
LoadAndSpill(node->enumerable());
// Both SpiderMonkey and kjs ignore null and undefined in contrast
// to the specification. 12.6.4 mandates a call to ToObject.
frame_->EmitPop(eax);
// eax: value to be iterated over
__ cmp(eax, Factory::undefined_value());
exit.Branch(equal);
__ cmp(eax, Factory::null_value());
exit.Branch(equal);
// Stack layout in body:
// [iteration counter (smi)] <- slot 0
// [length of array] <- slot 1
// [FixedArray] <- slot 2
// [Map or 0] <- slot 3
// [Object] <- slot 4
// Check if enumerable is already a JSObject
// eax: value to be iterated over
__ test(eax, Immediate(kSmiTagMask));
primitive.Branch(zero);
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
jsobject.Branch(above_equal);
primitive.Bind();
frame_->EmitPush(eax);
frame_->InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION, 1);
// function call returns the value in eax, which is where we want it below
jsobject.Bind();
// Get the set of properties (as a FixedArray or Map).
// eax: value to be iterated over
frame_->EmitPush(eax); // push the object being iterated over (slot 4)
frame_->EmitPush(eax); // push the Object (slot 4) for the runtime call
frame_->CallRuntime(Runtime::kGetPropertyNamesFast, 1);
// If we got a Map, we can do a fast modification check.
// Otherwise, we got a FixedArray, 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);
// Get enum cache
// eax: map (result from call to Runtime::kGetPropertyNamesFast)
__ 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));
__ shl(eax, kSmiTagSize);
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));
__ shl(eax, kSmiTagSize);
frame_->EmitPush(eax); // <- slot 1
frame_->EmitPush(Immediate(Smi::FromInt(0))); // <- slot 0
// Condition.
entry.Bind();
// Grab the current frame's height for the break and continue
// targets only after all the state is pushed on the frame.
node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
__ mov(eax, frame_->ElementAt(0)); // load the current count
__ cmp(eax, frame_->ElementAt(1)); // compare to the array length
node->break_target()->Branch(above_equal);
// Get the i'th entry of the array.
__ mov(edx, frame_->ElementAt(2));
__ mov(ebx, Operand(edx, eax, times_2,
FixedArray::kHeaderSize - kHeapObjectTag));
// Get the expected map from the stack or a zero map in the
// permanent slow case eax: current iteration count ebx: i'th entry
// of the enum cache
__ mov(edx, frame_->ElementAt(3));
// Check if the expected map still matches that of the enumerable.
// If not, we have to filter the key.
// eax: current iteration count
// ebx: i'th entry of the enum cache
// edx: expected map value
__ mov(ecx, frame_->ElementAt(4));
__ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
__ cmp(ecx, Operand(edx));
end_del_check.Branch(equal);
// Convert the entry to a string (or null if it isn't a property anymore).
frame_->EmitPush(frame_->ElementAt(4)); // push enumerable
frame_->EmitPush(ebx); // push entry
frame_->InvokeBuiltin(Builtins::FILTER_KEY, CALL_FUNCTION, 2);
__ mov(ebx, Operand(eax));
// If the property has been removed while iterating, we just skip it.
__ cmp(ebx, Factory::null_value());
node->continue_target()->Branch(equal);
end_del_check.Bind();
// Store the entry in the 'each' expression and take another spin in the
// loop. edx: i'th entry of the enum cache (or string there of)
frame_->EmitPush(ebx);
{ Reference each(this, node->each());
// Loading a reference may leave the frame in an unspilled state.
frame_->SpillAll();
if (!each.is_illegal()) {
if (each.size() > 0) {
frame_->EmitPush(frame_->ElementAt(each.size()));
}
// 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);
if (each.size() > 0) {
// It's safe to pop the value lying on top of the reference before
// unloading the reference itself (which preserves the top of stack,
// ie, now the topmost value of the non-zero sized reference), since
// we will discard the top of stack after unloading the reference
// anyway.
frame_->Drop();
}
}
}
// Unloading a reference may leave the frame in an unspilled state.
frame_->SpillAll();
// Discard the i'th entry pushed above or else the remainder of the
// reference, whichever is currently on top of the stack.
frame_->Drop();
// 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.
{ Reference ref(this, node->catch_var());
ASSERT(ref.is_slot());
// Load the exception to the top of the stack. Here we make use of the
// convenient property that it doesn't matter whether a value is
// immediately on top of or underneath a zero-sized reference.
ref.SetValue(NOT_CONST_INIT);
}
// Remove the exception from the stack.
frame_->Drop();
VisitStatementsAndSpill(node->catch_block()->statements());
if (has_valid_frame()) {
exit.Jump();
}
// --- Try block ---
try_block.Bind();
frame_->PushTryHandler(TRY_CATCH_HANDLER);
int handler_height = frame_->height();
// Shadow the jump targets for all escapes from the try block, including
// returns. During shadowing, the original target is hidden as the
// ShadowTarget and operations on the original actually affect the
// shadowing target.
//
// We should probably try to unify the escaping targets and the return
// target.
int nof_escapes = node->escaping_targets()->length();
List<ShadowTarget*> shadows(1 + nof_escapes);
// Add the shadow target for the function return.
static const int kReturnShadowIndex = 0;
shadows.Add(new ShadowTarget(&function_return_));
bool function_return_was_shadowed = function_return_is_shadowed_;
function_return_is_shadowed_ = true;
ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
// Add the remaining shadow targets.
for (int i = 0; i < nof_escapes; i++) {
shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
}
// Generate code for the statements in the try block.
VisitStatementsAndSpill(node->try_block()->statements());
// Stop the introduced shadowing and count the number of required unlinks.
// After shadowing stops, the original targets are unshadowed and the
// ShadowTargets represent the formerly shadowing targets.
bool has_unlinks = false;
for (int i = 0; i < shadows.length(); i++) {
shadows[i]->StopShadowing();
has_unlinks = has_unlinks || shadows[i]->is_linked();
}
function_return_is_shadowed_ = function_return_was_shadowed;
// Get an external reference to the handler address.
ExternalReference handler_address(Top::k_handler_address);
// Make sure that there's nothing left on the stack above the
// handler structure.
if (FLAG_debug_code) {
__ mov(eax, Operand::StaticVariable(handler_address));
__ cmp(esp, Operand(eax));
__ Assert(equal, "stack pointer should point to top handler");
}
// If we can fall off the end of the try block, unlink from try chain.
if (has_valid_frame()) {
// The next handler address is on top of the frame. Unlink from
// the handler list and drop the rest of this handler from the
// frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (has_unlinks) {
exit.Jump();
}
}
// Generate unlink code for the (formerly) shadowing targets that
// have been jumped to. Deallocate each shadow target.
Result return_value;
for (int i = 0; i < shadows.length(); i++) {
if (shadows[i]->is_linked()) {
// Unlink from try chain; be careful not to destroy the TOS if
// there is one.
if (i == kReturnShadowIndex) {
shadows[i]->Bind(&return_value);
return_value.ToRegister(eax);
} else {
shadows[i]->Bind();
}
// Because we can be jumping here (to spilled code) from
// unspilled code, we need to reestablish a spilled frame at
// this block.
frame_->SpillAll();
// Reload sp from the top handler, because some statements that we
// break from (eg, for...in) may have left stuff on the stack.
__ mov(esp, Operand::StaticVariable(handler_address));
frame_->Forget(frame_->height() - handler_height);
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (i == kReturnShadowIndex) {
if (!function_return_is_shadowed_) frame_->PrepareForReturn();
shadows[i]->other_target()->Jump(&return_value);
} else {
shadows[i]->other_target()->Jump();
}
}
}
exit.Bind();
}
void CodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* node) {
ASSERT(!in_spilled_code());
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ TryFinallyStatement");
CodeForStatementPosition(node);
// State: Used to keep track of reason for entering the finally
// block. Should probably be extended to hold information for
// break/continue from within the try block.
enum { FALLING, THROWING, JUMPING };
JumpTarget try_block;
JumpTarget finally_block;
try_block.Call();
frame_->EmitPush(eax);
// In case of thrown exceptions, this is where we continue.
__ Set(ecx, Immediate(Smi::FromInt(THROWING)));
finally_block.Jump();
// --- Try block ---
try_block.Bind();
frame_->PushTryHandler(TRY_FINALLY_HANDLER);
int handler_height = frame_->height();
// Shadow the jump targets for all escapes from the try block, including
// returns. During shadowing, the original target is hidden as the
// ShadowTarget and operations on the original actually affect the
// shadowing target.
//
// We should probably try to unify the escaping targets and the return
// target.
int nof_escapes = node->escaping_targets()->length();
List<ShadowTarget*> shadows(1 + nof_escapes);
// Add the shadow target for the function return.
static const int kReturnShadowIndex = 0;
shadows.Add(new ShadowTarget(&function_return_));
bool function_return_was_shadowed = function_return_is_shadowed_;
function_return_is_shadowed_ = true;
ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
// Add the remaining shadow targets.
for (int i = 0; i < nof_escapes; i++) {
shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
}
// Generate code for the statements in the try block.
VisitStatementsAndSpill(node->try_block()->statements());
// Stop the introduced shadowing and count the number of required unlinks.
// After shadowing stops, the original targets are unshadowed and the
// ShadowTargets represent the formerly shadowing targets.
int nof_unlinks = 0;
for (int i = 0; i < shadows.length(); i++) {
shadows[i]->StopShadowing();
if (shadows[i]->is_linked()) nof_unlinks++;
}
function_return_is_shadowed_ = function_return_was_shadowed;
// Get an external reference to the handler address.
ExternalReference handler_address(Top::k_handler_address);
// If we can fall off the end of the try block, unlink from the try
// chain and set the state on the frame to FALLING.
if (has_valid_frame()) {
// The next handler address is on top of the frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
// Fake a top of stack value (unneeded when FALLING) and set the
// state in ecx, then jump around the unlink blocks if any.
frame_->EmitPush(Immediate(Factory::undefined_value()));
__ Set(ecx, Immediate(Smi::FromInt(FALLING)));
if (nof_unlinks > 0) {
finally_block.Jump();
}
}
// Generate code to unlink and set the state for the (formerly)
// shadowing targets that have been jumped to.
for (int i = 0; i < shadows.length(); i++) {
if (shadows[i]->is_linked()) {
// If we have come from the shadowed return, the return value is
// on the virtual frame. We must preserve it until it is
// pushed.
if (i == kReturnShadowIndex) {
Result return_value;
shadows[i]->Bind(&return_value);
return_value.ToRegister(eax);
} else {
shadows[i]->Bind();
}
// Because we can be jumping here (to spilled code) from
// unspilled code, we need to reestablish a spilled frame at
// this block.
frame_->SpillAll();
// Reload sp from the top handler, because some statements that
// we break from (eg, for...in) may have left stuff on the
// stack.
__ mov(esp, Operand::StaticVariable(handler_address));
frame_->Forget(frame_->height() - handler_height);
// Unlink this handler and drop it from the frame.
ASSERT(StackHandlerConstants::kNextOffset == 0);
frame_->EmitPop(Operand::StaticVariable(handler_address));
frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
if (i == kReturnShadowIndex) {
// If this target shadowed the function return, materialize
// the return value on the stack.
frame_->EmitPush(eax);
} else {
// Fake TOS for targets that shadowed breaks and continues.
frame_->EmitPush(Immediate(Factory::undefined_value()));
}
__ Set(ecx, Immediate(Smi::FromInt(JUMPING + i)));
if (--nof_unlinks > 0) {
// If this is not the last unlink block, jump around the next.
finally_block.Jump();
}
}
}
// --- Finally block ---
finally_block.Bind();
// Push the state on the stack.
frame_->EmitPush(ecx);
// We keep two elements on the stack - the (possibly faked) result
// and the state - while evaluating the finally block.
//
// Generate code for the statements in the finally block.
VisitStatementsAndSpill(node->finally_block()->statements());
if (has_valid_frame()) {
// Restore state and return value or faked TOS.
frame_->EmitPop(ecx);
frame_->EmitPop(eax);
}
// Generate code to jump to the right destination for all used
// formerly shadowing targets. Deallocate each shadow target.
for (int i = 0; i < shadows.length(); i++) {
if (has_valid_frame() && shadows[i]->is_bound()) {
BreakTarget* original = shadows[i]->other_target();
__ cmp(Operand(ecx), Immediate(Smi::FromInt(JUMPING + i)));
if (i == kReturnShadowIndex) {
// The return value is (already) in eax.
Result return_value = allocator_->Allocate(eax);
ASSERT(return_value.is_valid());
if (function_return_is_shadowed_) {
original->Branch(equal, &return_value);
} else {
// Branch around the preparation for return which may emit
// code.
JumpTarget skip;
skip.Branch(not_equal);
frame_->PrepareForReturn();
original->Jump(&return_value);
skip.Bind();
}
} else {
original->Branch(equal);
}
}
}
if (has_valid_frame()) {
// Check if we need to rethrow the exception.
JumpTarget exit;
__ cmp(Operand(ecx), Immediate(Smi::FromInt(THROWING)));
exit.Branch(not_equal);
// Rethrow exception.
frame_->EmitPush(eax); // undo pop from above
frame_->CallRuntime(Runtime::kReThrow, 1);
// Done.
exit.Bind();
}
}
void CodeGenerator::VisitDebuggerStatement(DebuggerStatement* node) {
ASSERT(!in_spilled_code());
Comment cmnt(masm_, "[ DebuggerStatement");
CodeForStatementPosition(node);
#ifdef ENABLE_DEBUGGER_SUPPORT
// Spill everything, even constants, to the frame.
frame_->SpillAll();
frame_->CallRuntime(Runtime::kDebugBreak, 0);
// Ignore the return value.
#endif
}
void CodeGenerator::InstantiateBoilerplate(Handle<JSFunction> boilerplate) {
// Call the runtime to instantiate the function boilerplate object.
// 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.
ASSERT(boilerplate->IsBoilerplate());
frame_->SyncRange(0, frame_->element_count() - 1);
// Create a new closure.
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(boilerplate));
Result result = frame_->CallRuntime(Runtime::kNewClosure, 2);
frame_->Push(&result);
}
void CodeGenerator::VisitFunctionLiteral(FunctionLiteral* node) {
Comment cmnt(masm_, "[ FunctionLiteral");
// Build the function boilerplate and instantiate it.
Handle<JSFunction> boilerplate = BuildBoilerplate(node);
// Check for stack-overflow exception.
if (HasStackOverflow()) return;
InstantiateBoilerplate(boilerplate);
}
void CodeGenerator::VisitFunctionBoilerplateLiteral(
FunctionBoilerplateLiteral* node) {
Comment cmnt(masm_, "[ FunctionBoilerplateLiteral");
InstantiateBoilerplate(node->boilerplate());
}
void CodeGenerator::VisitConditional(Conditional* node) {
Comment cmnt(masm_, "[ Conditional");
JumpTarget then;
JumpTarget else_;
JumpTarget exit;
ControlDestination dest(&then, &else_, true);
LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, true);
if (dest.false_was_fall_through()) {
// The else target was bound, so we compile the else part first.
Load(node->else_expression(), typeof_state());
if (then.is_linked()) {
exit.Jump();
then.Bind();
Load(node->then_expression(), typeof_state());
}
} else {
// The then target was bound, so we compile the then part first.
Load(node->then_expression(), typeof_state());
if (else_.is_linked()) {
exit.Jump();
else_.Bind();
Load(node->else_expression(), typeof_state());
}
}
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 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) {
value = LoadFromGlobalSlotCheckExtensions(slot, typeof_state, &slow);
// If there was no control flow to slow, we can exit early.
if (!slow.is_linked()) {
frame_->Push(&value);
return;
}
done.Jump(&value);
} else if (slot->var()->mode() == Variable::DYNAMIC_LOCAL) {
Slot* potential_slot = slot->var()->local_if_not_shadowed()->slot();
// Only generate the fast case for locals that rewrite to slots.
// This rules out argument loads.
if (potential_slot != NULL) {
// Allocate a fresh register to use as a temp in
// ContextSlotOperandCheckExtensions and to hold the result
// value.
value = allocator_->Allocate();
ASSERT(value.is_valid());
__ mov(value.reg(),
ContextSlotOperandCheckExtensions(potential_slot,
value,
&slow));
if (potential_slot->var()->mode() == Variable::CONST) {
__ cmp(value.reg(), Factory::the_hole_value());
done.Branch(not_equal, &value);
__ mov(value.reg(), Factory::undefined_value());
}
// There is always control flow to slow from
// ContextSlotOperandCheckExtensions so we have to jump around
// it.
done.Jump(&value);
}
}
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");
JumpTarget exit;
__ mov(ecx, SlotOperand(slot, ecx));
__ cmp(ecx, Factory::the_hole_value());
exit.Branch(not_equal);
__ mov(ecx, Factory::undefined_value());
exit.Bind();
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;
// Pop the loaded value from the stack.
Result value = frame_->Pop();
// If the loaded value is a constant, we know if the arguments
// object has been lazily loaded yet.
if (value.is_constant()) {
if (value.handle()->IsTheHole()) {
Result arguments = StoreArgumentsObject(false);
frame_->Push(&arguments);
} else {
frame_->Push(&value);
}
return;
}
// 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(value.reg()), Immediate(Factory::the_hole_value()));
frame_->Push(&value);
exit.Branch(not_equal);
Result arguments = StoreArgumentsObject(false);
frame_->SetElementAt(0, &arguments);
exit.Bind();
}
Result CodeGenerator::LoadFromGlobalSlotCheckExtensions(
Slot* slot,
TypeofState typeof_state,
JumpTarget* slow) {
// Check that no extension objects have been created by calls to
// eval from the current scope to the global scope.
Register context = esi;
Result tmp = allocator_->Allocate();
ASSERT(tmp.is_valid()); // All non-reserved registers were available.
Scope* s = scope();
while (s != NULL) {
if (s->num_heap_slots() > 0) {
if (s->calls_eval()) {
// Check that extension is NULL.
__ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
Immediate(0));
slow->Branch(not_equal, not_taken);
}
// Load next context in chain.
__ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
context = tmp.reg();
}
// If no outer scope calls eval, we do not need to check more
// context extensions. If we have reached an eval scope, we check
// all extensions from this point.
if (!s->outer_scope_calls_eval() || s->is_eval_scope()) break;
s = s->outer_scope();
}
if (s != NULL && s->is_eval_scope()) {
// Loop up the context chain. There is no frame effect so it is
// safe to use raw labels here.
Label next, fast;
if (!context.is(tmp.reg())) {
__ mov(tmp.reg(), context);
}
__ bind(&next);
// Terminate at global context.
__ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
Immediate(Factory::global_context_map()));
__ j(equal, &fast);
// Check that extension is NULL.
__ cmp(ContextOperand(tmp.reg(), Context::EXTENSION_INDEX), Immediate(0));
slow->Branch(not_equal, not_taken);
// Load next context in chain.
__ mov(tmp.reg(), ContextOperand(tmp.reg(), Context::CLOSURE_INDEX));
__ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
__ jmp(&next);
__ bind(&fast);
}
tmp.Unuse();
// All extension objects were empty and it is safe to use a global
// load IC call.
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();
// Discard the global object. The result is in answer.
frame_->Drop();
return answer;
}
void CodeGenerator::StoreToSlot(Slot* slot, InitState init_state) {
if (slot->type() == Slot::LOOKUP) {
ASSERT(slot->var()->is_dynamic());
// For now, just do a runtime call. Since the call is inevitable,
// we eagerly sync the virtual frame so we can directly push the
// arguments into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(slot->var()->name()));
Result value;
if (init_state == CONST_INIT) {
// Same as the case for a normal store, but ignores attribute
// (e.g. READ_ONLY) of context slot so that we can initialize const
// properties (introduced via eval("const foo = (some expr);")). Also,
// uses the current function context instead of the top context.
//
// Note that we must declare the foo upon entry of eval(), via a
// context slot declaration, but we cannot initialize it at the same
// time, because the const declaration may be at the end of the eval
// code (sigh...) and the const variable may have been used before
// (where its value is 'undefined'). Thus, we can only do the
// initialization when we actually encounter the expression and when
// the expression operands are defined and valid, and thus we need the
// split into 2 operations: declaration of the context slot followed
// by initialization.
value = frame_->CallRuntime(Runtime::kInitializeConstContextSlot, 3);
} else {
value = frame_->CallRuntime(Runtime::kStoreContextSlot, 3);
}
// Storing a variable must keep the (new) value on the expression
// stack. This is necessary for compiling chained assignment
// expressions.
frame_->Push(&value);
} else {
ASSERT(!slot->var()->is_dynamic());
JumpTarget exit;
if (init_state == CONST_INIT) {
ASSERT(slot->var()->mode() == Variable::CONST);
// Only the first const initialization must be executed (the slot
// still contains 'the hole' value). When the assignment is executed,
// the code is identical to a normal store (see below).
//
// We spill the frame in the code below because the direct-frame
// access of SlotOperand is potentially unsafe with an unspilled
// frame.
VirtualFrame::SpilledScope spilled_scope;
Comment cmnt(masm_, "[ Init const");
__ mov(ecx, SlotOperand(slot, ecx));
__ cmp(ecx, Factory::the_hole_value());
exit.Branch(not_equal);
}
// We must execute the store. Storing a variable must keep the (new)
// value on the stack. This is necessary for compiling assignment
// expressions.
//
// Note: We will reach here even with slot->var()->mode() ==
// Variable::CONST because of const declarations which will initialize
// consts to 'the hole' value and by doing so, end up calling this code.
if (slot->type() == Slot::PARAMETER) {
frame_->StoreToParameterAt(slot->index());
} else if (slot->type() == Slot::LOCAL) {
frame_->StoreToLocalAt(slot->index());
} else {
// The other slot types (LOOKUP and GLOBAL) cannot reach here.
//
// The use of SlotOperand below is safe for an unspilled frame
// because the slot is a context slot.
ASSERT(slot->type() == Slot::CONTEXT);
frame_->Dup();
Result value = frame_->Pop();
value.ToRegister();
Result start = allocator_->Allocate();
ASSERT(start.is_valid());
__ mov(SlotOperand(slot, start.reg()), value.reg());
// RecordWrite may destroy the value registers.
//
// TODO(204): Avoid actually spilling when the value is not
// needed (probably the common case).
frame_->Spill(value.reg());
int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
Result temp = allocator_->Allocate();
ASSERT(temp.is_valid());
__ RecordWrite(start.reg(), offset, value.reg(), temp.reg());
// The results start, value, and temp are unused by going out of
// scope.
}
exit.Bind();
}
}
void CodeGenerator::VisitSlot(Slot* node) {
Comment cmnt(masm_, "[ Slot");
LoadFromSlotCheckForArguments(node, typeof_state());
}
void CodeGenerator::VisitVariableProxy(VariableProxy* node) {
Comment cmnt(masm_, "[ VariableProxy");
Variable* var = node->var();
Expression* expr = var->rewrite();
if (expr != NULL) {
Visit(expr);
} else {
ASSERT(var->is_global());
Reference ref(this, node);
ref.GetValue(typeof_state());
}
}
void CodeGenerator::VisitLiteral(Literal* node) {
Comment cmnt(masm_, "[ Literal");
frame_->Push(node->handle());
}
void CodeGenerator::LoadUnsafeSmi(Register target, Handle<Object> value) {
ASSERT(target.is_valid());
ASSERT(value->IsSmi());
int bits = reinterpret_cast<int>(*value);
__ Set(target, Immediate(bits & 0x0000FFFF));
__ xor_(target, bits & 0xFFFF0000);
}
bool CodeGenerator::IsUnsafeSmi(Handle<Object> value) {
if (!value->IsSmi()) return false;
int int_value = Smi::cast(*value)->value();
return !is_intn(int_value, kMaxSmiInlinedBits);
}
// Materialize the regexp literal 'node' in the literals array
// 'literals' of the function. Leave the regexp boilerplate in
// 'boilerplate'.
class DeferredRegExpLiteral: public DeferredCode {
public:
DeferredRegExpLiteral(Register boilerplate,
Register literals,
RegExpLiteral* node)
: boilerplate_(boilerplate), literals_(literals), node_(node) {
set_comment("[ DeferredRegExpLiteral");
}
void Generate();
private:
Register boilerplate_;
Register literals_;
RegExpLiteral* node_;
};
void DeferredRegExpLiteral::Generate() {
// Since the entry is undefined we call the runtime system to
// compute the literal.
// Literal array (0).
__ push(literals_);
// Literal index (1).
__ push(Immediate(Smi::FromInt(node_->literal_index())));
// RegExp pattern (2).
__ push(Immediate(node_->pattern()));
// RegExp flags (3).
__ push(Immediate(node_->flags()));
__ CallRuntime(Runtime::kMaterializeRegExpLiteral, 4);
if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
}
void CodeGenerator::VisitRegExpLiteral(RegExpLiteral* node) {
Comment cmnt(masm_, "[ RegExp Literal");
// Retrieve the literals array and check the allocated entry. Begin
// with a writable copy of the function of this activation in a
// register.
frame_->PushFunction();
Result literals = frame_->Pop();
literals.ToRegister();
frame_->Spill(literals.reg());
// Load the literals array of the function.
__ mov(literals.reg(),
FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
// Load the literal at the ast saved index.
Result boilerplate = allocator_->Allocate();
ASSERT(boilerplate.is_valid());
int literal_offset =
FixedArray::kHeaderSize + node->literal_index() * kPointerSize;
__ mov(boilerplate.reg(), FieldOperand(literals.reg(), literal_offset));
// Check whether we need to materialize the RegExp object. If so,
// jump to the deferred code passing the literals array.
DeferredRegExpLiteral* deferred =
new DeferredRegExpLiteral(boilerplate.reg(), literals.reg(), node);
__ cmp(boilerplate.reg(), Factory::undefined_value());
deferred->Branch(equal);
deferred->BindExit();
literals.Unuse();
// Push the boilerplate object.
frame_->Push(&boilerplate);
}
// Materialize the object literal 'node' in the literals array
// 'literals' of the function. Leave the object boilerplate in
// 'boilerplate'.
class DeferredObjectLiteral: public DeferredCode {
public:
DeferredObjectLiteral(Register boilerplate,
Register literals,
ObjectLiteral* node)
: boilerplate_(boilerplate), literals_(literals), node_(node) {
set_comment("[ DeferredObjectLiteral");
}
void Generate();
private:
Register boilerplate_;
Register literals_;
ObjectLiteral* node_;
};
void DeferredObjectLiteral::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())));
// Constant properties (2).
__ push(Immediate(node_->constant_properties()));
__ CallRuntime(Runtime::kCreateObjectLiteralBoilerplate, 3);
if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
}
void CodeGenerator::VisitObjectLiteral(ObjectLiteral* node) {
Comment cmnt(masm_, "[ ObjectLiteral");
// 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 object literal boilerplate.
// If so, jump to the deferred code passing the literals array.
DeferredObjectLiteral* deferred =
new DeferredObjectLiteral(boilerplate.reg(), literals.reg(), node);
__ cmp(boilerplate.reg(), Factory::undefined_value());
deferred->Branch(equal);
deferred->BindExit();
literals.Unuse();
// Push the boilerplate object.
frame_->Push(&boilerplate);
// Clone the boilerplate object.
Runtime::FunctionId clone_function_id = Runtime::kCloneLiteralBoilerplate;
if (node->depth() == 1) {
clone_function_id = Runtime::kCloneShallowLiteralBoilerplate;
}
Result clone = frame_->CallRuntime(clone_function_id, 1);
// Push the newly cloned literal object as the result.
frame_->Push(&clone);
for (int i = 0; i < node->properties()->length(); i++) {
ObjectLiteral::Property* property = node->properties()->at(i);
switch (property->kind()) {
case ObjectLiteral::Property::CONSTANT:
break;
case ObjectLiteral::Property::MATERIALIZED_LITERAL:
if (CompileTimeValue::IsCompileTimeValue(property->value())) break;
// else fall through.
case ObjectLiteral::Property::COMPUTED: {
Handle<Object> key(property->key()->handle());
if (key->IsSymbol()) {
// Duplicate the object as the IC receiver.
frame_->Dup();
Load(property->value());
frame_->Push(key);
Result ignored = frame_->CallStoreIC();
// Drop the duplicated receiver and ignore the result.
frame_->Drop();
break;
}
// Fall through
}
case ObjectLiteral::Property::PROTOTYPE: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kSetProperty, 3);
// Ignore the result.
break;
}
case ObjectLiteral::Property::SETTER: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
frame_->Push(Smi::FromInt(1));
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
// Ignore the result.
break;
}
case ObjectLiteral::Property::GETTER: {
// Duplicate the object as an argument to the runtime call.
frame_->Dup();
Load(property->key());
frame_->Push(Smi::FromInt(0));
Load(property->value());
Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
// Ignore the result.
break;
}
default: UNREACHABLE();
}
}
}
// Materialize the array literal 'node' in the literals array 'literals'
// of the function. Leave the array boilerplate in 'boilerplate'.
class DeferredArrayLiteral: public DeferredCode {
public:
DeferredArrayLiteral(Register boilerplate,
Register literals,
ArrayLiteral* node)
: boilerplate_(boilerplate), literals_(literals), node_(node) {
set_comment("[ DeferredArrayLiteral");
}
void Generate();
private:
Register boilerplate_;
Register literals_;
ArrayLiteral* node_;
};
void DeferredArrayLiteral::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())));
// Constant properties (2).
__ push(Immediate(node_->literals()));
__ CallRuntime(Runtime::kCreateArrayLiteralBoilerplate, 3);
if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
}
void CodeGenerator::VisitArrayLiteral(ArrayLiteral* node) {
Comment cmnt(masm_, "[ ArrayLiteral");
// 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 object literal boilerplate.
// If so, jump to the deferred code passing the literals array.
DeferredArrayLiteral* deferred =
new DeferredArrayLiteral(boilerplate.reg(), literals.reg(), node);
__ cmp(boilerplate.reg(), Factory::undefined_value());
deferred->Branch(equal);
deferred->BindExit();
literals.Unuse();
// Push the resulting array literal boilerplate on the stack.
frame_->Push(&boilerplate);
// Clone the boilerplate object.
Runtime::FunctionId clone_function_id = Runtime::kCloneLiteralBoilerplate;
if (node->depth() == 1) {
clone_function_id = Runtime::kCloneShallowLiteralBoilerplate;
}
Result clone = frame_->CallRuntime(clone_function_id, 1);
// Push the newly cloned literal object as the result.
frame_->Push(&clone);
// Generate code to set the elements in the array that are not
// literals.
for (int i = 0; i < node->values()->length(); i++) {
Expression* value = node->values()->at(i);
// If value is a literal the property value is already set in the
// boilerplate object.
if (value->AsLiteral() != NULL) continue;
// If value is a materialized literal the property value is already set
// in the boilerplate object if it is simple.
if (CompileTimeValue::IsCompileTimeValue(value)) continue;
// The property must be set by generated code.
Load(value);
// Get the property value off the stack.
Result prop_value = frame_->Pop();
prop_value.ToRegister();
// Fetch the array literal while leaving a copy on the stack and
// use it to get the elements array.
frame_->Dup();
Result elements = frame_->Pop();
elements.ToRegister();
frame_->Spill(elements.reg());
// Get the elements array.
__ mov(elements.reg(),
FieldOperand(elements.reg(), JSObject::kElementsOffset));
// Write to the indexed properties array.
int offset = i * kPointerSize + FixedArray::kHeaderSize;
__ mov(FieldOperand(elements.reg(), offset), prop_value.reg());
// Update the write barrier for the array address.
frame_->Spill(prop_value.reg()); // Overwritten by the write barrier.
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
__ RecordWrite(elements.reg(), offset, prop_value.reg(), scratch.reg());
}
}
void CodeGenerator::VisitCatchExtensionObject(CatchExtensionObject* node) {
ASSERT(!in_spilled_code());
// Call runtime routine to allocate the catch extension object and
// assign the exception value to the catch variable.
Comment cmnt(masm_, "[ CatchExtensionObject");
Load(node->key());
Load(node->value());
Result result =
frame_->CallRuntime(Runtime::kCreateCatchExtensionObject, 2);
frame_->Push(&result);
}
void CodeGenerator::VisitAssignment(Assignment* node) {
Comment cmnt(masm_, "[ Assignment");
{ Reference target(this, node->target());
if (target.is_illegal()) {
// Fool the virtual frame into thinking that we left the assignment's
// value on the frame.
frame_->Push(Smi::FromInt(0));
return;
}
Variable* var = node->target()->AsVariableProxy()->AsVariable();
if (node->starts_initialization_block()) {
ASSERT(target.type() == Reference::NAMED ||
target.type() == Reference::KEYED);
// Change to slow case in the beginning of an initialization
// block to avoid the quadratic behavior of repeatedly adding
// fast properties.
// The receiver is the argument to the runtime call. It is the
// first value pushed when the reference was loaded to the
// frame.
frame_->PushElementAt(target.size() - 1);
Result ignored = frame_->CallRuntime(Runtime::kToSlowProperties, 1);
}
if (node->op() == Token::ASSIGN ||
node->op() == Token::INIT_VAR ||
node->op() == Token::INIT_CONST) {
Load(node->value());
} else {
Literal* literal = node->value()->AsLiteral();
bool overwrite_value =
(node->value()->AsBinaryOperation() != NULL &&
node->value()->AsBinaryOperation()->ResultOverwriteAllowed());
Variable* right_var = node->value()->AsVariableProxy()->AsVariable();
// There are two cases where the target is not read in the right hand
// side, that are easy to test for: the right hand side is a literal,
// or the right hand side is a different variable. TakeValue invalidates
// the target, with an implicit promise that it will be written to again
// before it is read.
if (literal != NULL || (right_var != NULL && right_var != var)) {
target.TakeValue(NOT_INSIDE_TYPEOF);
} else {
target.GetValue(NOT_INSIDE_TYPEOF);
}
Load(node->value());
GenericBinaryOperation(node->binary_op(),
node->type(),
overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
}
if (var != NULL &&
var->mode() == Variable::CONST &&
node->op() != Token::INIT_VAR && node->op() != Token::INIT_CONST) {
// Assignment ignored - leave the value on the stack.
} else {
CodeForSourcePosition(node->position());
if (node->op() == Token::INIT_CONST) {
// Dynamic constant initializations must use the function context
// and initialize the actual constant declared. Dynamic variable
// initializations are simply assignments and use SetValue.
target.SetValue(CONST_INIT);
} else {
target.SetValue(NOT_CONST_INIT);
}
if (node->ends_initialization_block()) {
ASSERT(target.type() == Reference::NAMED ||
target.type() == Reference::KEYED);
// End of initialization block. Revert to fast case. The
// argument to the runtime call is the receiver, which is the
// first value pushed as part of the reference, which is below
// the lhs value.
frame_->PushElementAt(target.size());
Result ignored = frame_->CallRuntime(Runtime::kToFastProperties, 1);
}
}
}
}
void CodeGenerator::VisitThrow(Throw* node) {
Comment cmnt(masm_, "[ Throw");
Load(node->exception());
Result result = frame_->CallRuntime(Runtime::kThrow, 1);
frame_->Push(&result);
}
void CodeGenerator::VisitProperty(Property* node) {
Comment cmnt(masm_, "[ Property");
Reference property(this, node);
property.GetValue(typeof_state());
}
void CodeGenerator::VisitCall(Call* node) {
Comment cmnt(masm_, "[ Call");
Expression* function = node->expression();
ZoneList<Expression*>* args = node->arguments();
// Check if the function is a variable or a property.
Variable* var = function->AsVariableProxy()->AsVariable();
Property* property = function->AsProperty();
// ------------------------------------------------------------------------
// Fast-case: Use inline caching.
// ---
// According to ECMA-262, section 11.2.3, page 44, the function to call
// must be resolved after the arguments have been evaluated. The IC code
// automatically handles this by loading the arguments before the function
// is resolved in cache misses (this also holds for megamorphic calls).
// ------------------------------------------------------------------------
if (var != NULL && var->is_possibly_eval()) {
// ----------------------------------
// JavaScript example: 'eval(arg)' // eval is not known to be shadowed
// ----------------------------------
// In a call to eval, we first call %ResolvePossiblyDirectEval to
// resolve the function we need to call and the receiver of the
// call. Then we call the resolved function using the given
// arguments.
// Prepare the stack for the call to the resolved function.
Load(function);
// Allocate a frame slot for the receiver.
frame_->Push(Factory::undefined_value());
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Prepare the stack for the call to ResolvePossiblyDirectEval.
frame_->PushElementAt(arg_count + 1);
if (arg_count > 0) {
frame_->PushElementAt(arg_count);
} else {
frame_->Push(Factory::undefined_value());
}
// Resolve the call.
Result result =
frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 2);
// Touch up the stack with the right values for the function and the
// receiver. Use a scratch register to avoid destroying the result.
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
__ mov(scratch.reg(), FieldOperand(result.reg(), FixedArray::kHeaderSize));
frame_->SetElementAt(arg_count + 1, &scratch);
// We can reuse the result register now.
frame_->Spill(result.reg());
__ mov(result.reg(),
FieldOperand(result.reg(), FixedArray::kHeaderSize + kPointerSize));
frame_->SetElementAt(arg_count, &result);
// Call the function.
CodeForSourcePosition(node->position());
InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
CallFunctionStub call_function(arg_count, in_loop);
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
// ----------------------------------
// Push the name of the function and the receiver onto the stack.
frame_->Push(var->name());
// 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));
}
// Call the IC initialization code.
CodeForSourcePosition(node->position());
Result result = frame_->CallCallIC(RelocInfo::CODE_TARGET_CONTEXT,
arg_count,
loop_nesting());
frame_->RestoreContextRegister();
// Replace the function on the stack with the result.
frame_->SetElementAt(0, &result);
} else if (var != NULL && var->slot() != NULL &&
var->slot()->type() == Slot::LOOKUP) {
// ----------------------------------
// JavaScript example: 'with (obj) foo(1, 2, 3)' // foo is in obj
// ----------------------------------
// Load the function from the context. Sync the frame so we can
// push the arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(var->name()));
frame_->CallRuntime(Runtime::kLoadContextSlot, 2);
// The runtime call returns a pair of values in eax and edx. The
// looked-up function is in eax and the receiver is in edx. These
// register references are not ref counted here. We spill them
// eagerly since they are arguments to an inevitable call (and are
// not sharable by the arguments).
ASSERT(!allocator()->is_used(eax));
frame_->EmitPush(eax);
// Load the receiver.
ASSERT(!allocator()->is_used(edx));
frame_->EmitPush(edx);
// Call the function.
CallWithArguments(args, 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,
args->at(0),
args->at(1)->AsVariableProxy(),
node->position());
} else {
// Push the name of the function and the receiver onto the stack.
frame_->Push(name);
Load(property->obj());
// Load the arguments.
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Call the IC initialization code.
CodeForSourcePosition(node->position());
Result result =
frame_->CallCallIC(RelocInfo::CODE_TARGET, arg_count,
loop_nesting());
frame_->RestoreContextRegister();
// Replace the function on the stack with the result.
frame_->SetElementAt(0, &result);
}
} else {
// -------------------------------------------
// JavaScript example: 'array[index](1, 2, 3)'
// -------------------------------------------
// Load the function to call from the property through a reference.
Reference ref(this, property);
ref.GetValue(NOT_INSIDE_TYPEOF);
// Pass receiver to called function.
if (property->is_synthetic()) {
// Use global object as receiver.
LoadGlobalReceiver();
} else {
// The reference's size is non-negative.
frame_->PushElementAt(ref.size());
}
// Call the function.
CallWithArguments(args, node->position());
}
} else {
// ----------------------------------
// JavaScript example: 'foo(1, 2, 3)' // foo is not global
// ----------------------------------
// Load the function.
Load(function);
// Pass the global proxy as the receiver.
LoadGlobalReceiver();
// Call the function.
CallWithArguments(args, node->position());
}
}
void CodeGenerator::VisitCallNew(CallNew* node) {
Comment cmnt(masm_, "[ CallNew");
// According to ECMA-262, section 11.2.2, page 44, the function
// expression in new calls must be evaluated before the
// arguments. This is different from ordinary calls, where the
// actual function to call is resolved after the arguments have been
// evaluated.
// Compute function to call and use the global object as the
// receiver. There is no need to use the global proxy here because
// it will always be replaced with a newly allocated object.
Load(node->expression());
LoadGlobal();
// Push the arguments ("left-to-right") on the stack.
ZoneList<Expression*>* args = node->arguments();
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
// Call the construct call builtin that handles allocation and
// constructor invocation.
CodeForSourcePosition(node->position());
Result result = frame_->CallConstructor(arg_count);
// Replace the function on the stack with the result.
frame_->SetElementAt(0, &result);
}
void CodeGenerator::GenerateIsSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask));
value.Unuse();
destination()->Split(zero);
}
void CodeGenerator::GenerateLog(ZoneList<Expression*>* args) {
// Conditionally generate a log call.
// Args:
// 0 (literal string): The type of logging (corresponds to the flags).
// This is used to determine whether or not to generate the log call.
// 1 (string): Format string. Access the string at argument index 2
// with '%2s' (see Logger::LogRuntime for all the formats).
// 2 (array): Arguments to the format string.
ASSERT_EQ(args->length(), 3);
#ifdef ENABLE_LOGGING_AND_PROFILING
if (ShouldGenerateLog(args->at(0))) {
Load(args->at(1));
Load(args->at(2));
frame_->CallRuntime(Runtime::kLog, 2);
}
#endif
// Finally, we're expected to leave a value on the top of the stack.
frame_->Push(Factory::undefined_value());
}
void CodeGenerator::GenerateIsNonNegativeSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask | 0x80000000));
value.Unuse();
destination()->Split(zero);
}
// This generates code that performs a charCodeAt() call or returns
// undefined in order to trigger the slow case, Runtime_StringCharCodeAt.
// It can handle flat and sliced strings, 8 and 16 bit characters and
// cons strings where the answer is found in the left hand branch of the
// cons. The slow case will flatten the string, which will ensure that
// the answer is in the left hand side the next time around.
void CodeGenerator::GenerateFastCharCodeAt(ZoneList<Expression*>* args) {
Comment(masm_, "[ GenerateFastCharCodeAt");
ASSERT(args->length() == 2);
Label slow_case;
Label end;
Label not_a_flat_string;
Label a_cons_string;
Label try_again_with_new_string;
Label ascii_string;
Label got_char_code;
Load(args->at(0));
Load(args->at(1));
Result index = frame_->Pop();
Result object = frame_->Pop();
// Get register ecx to use as shift amount later.
Result shift_amount;
if (object.is_register() && object.reg().is(ecx)) {
Result fresh = allocator_->Allocate();
shift_amount = object;
object = fresh;
__ mov(object.reg(), ecx);
}
if (index.is_register() && index.reg().is(ecx)) {
Result fresh = allocator_->Allocate();
shift_amount = index;
index = fresh;
__ mov(index.reg(), ecx);
}
// There could be references to ecx in the frame. Allocating will
// spill them, otherwise spill explicitly.
if (shift_amount.is_valid()) {
frame_->Spill(ecx);
} else {
shift_amount = allocator()->Allocate(ecx);
}
ASSERT(shift_amount.is_register());
ASSERT(shift_amount.reg().is(ecx));
ASSERT(allocator_->count(ecx) == 1);
// We will mutate the index register and possibly the object register.
// The case where they are somehow the same register is handled
// because we only mutate them in the case where the receiver is a
// heap object and the index is not.
object.ToRegister();
index.ToRegister();
frame_->Spill(object.reg());
frame_->Spill(index.reg());
// We need a single extra temporary register.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// There is no virtual frame effect from here up to the final result
// push.
// If the receiver is a smi trigger the slow case.
ASSERT(kSmiTag == 0);
__ test(object.reg(), Immediate(kSmiTagMask));
__ j(zero, &slow_case);
// If the index is negative or non-smi trigger the slow case.
ASSERT(kSmiTag == 0);
__ test(index.reg(), Immediate(kSmiTagMask | 0x80000000));
__ j(not_zero, &slow_case);
// Untag the index.
__ sar(index.reg(), kSmiTagSize);
__ bind(&try_again_with_new_string);
// Fetch the instance type of the receiver into ecx.
__ mov(ecx, FieldOperand(object.reg(), HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
// If the receiver is not a string trigger the slow case.
__ test(ecx, Immediate(kIsNotStringMask));
__ j(not_zero, &slow_case);
// Here we make assumptions about the tag values and the shifts needed.
// See the comment in objects.h.
ASSERT(kLongStringTag == 0);
ASSERT(kMediumStringTag + String::kLongLengthShift ==
String::kMediumLengthShift);
ASSERT(kShortStringTag + String::kLongLengthShift ==
String::kShortLengthShift);
__ and_(ecx, kStringSizeMask);
__ add(Operand(ecx), Immediate(String::kLongLengthShift));
// Fetch the length field into the temporary register.
__ mov(temp.reg(), FieldOperand(object.reg(), String::kLengthOffset));
__ shr(temp.reg()); // The shift amount in ecx is implicit operand.
// Check for index out of range.
__ cmp(index.reg(), Operand(temp.reg()));
__ j(greater_equal, &slow_case);
// Reload the instance type (into the temp register this time)..
__ mov(temp.reg(), FieldOperand(object.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
// We need special handling for non-flat strings.
ASSERT(kSeqStringTag == 0);
__ test(temp.reg(), Immediate(kStringRepresentationMask));
__ j(not_zero, ¬_a_flat_string);
// Check for 1-byte or 2-byte string.
__ test(temp.reg(), Immediate(kStringEncodingMask));
__ j(not_zero, &ascii_string);
// 2-byte string.
// Load the 2-byte character code into the temp register.
__ movzx_w(temp.reg(), FieldOperand(object.reg(),
index.reg(),
times_2,
SeqTwoByteString::kHeaderSize));
__ jmp(&got_char_code);
// ASCII string.
__ bind(&ascii_string);
// Load the byte into the temp register.
__ movzx_b(temp.reg(), FieldOperand(object.reg(),
index.reg(),
times_1,
SeqAsciiString::kHeaderSize));
__ bind(&got_char_code);
ASSERT(kSmiTag == 0);
__ shl(temp.reg(), kSmiTagSize);
__ jmp(&end);
// Handle non-flat strings.
__ bind(¬_a_flat_string);
__ and_(temp.reg(), kStringRepresentationMask);
__ cmp(temp.reg(), kConsStringTag);
__ j(equal, &a_cons_string);
__ cmp(temp.reg(), kSlicedStringTag);
__ j(not_equal, &slow_case);
// SlicedString.
// Add the offset to the index and trigger the slow case on overflow.
__ add(index.reg(), FieldOperand(object.reg(), SlicedString::kStartOffset));
__ j(overflow, &slow_case);
// Getting the underlying string is done by running the cons string code.
// ConsString.
__ bind(&a_cons_string);
// Get the first of the two strings. Both sliced and cons strings
// store their source string at the same offset.
ASSERT(SlicedString::kBufferOffset == ConsString::kFirstOffset);
__ mov(object.reg(), FieldOperand(object.reg(), ConsString::kFirstOffset));
__ jmp(&try_again_with_new_string);
__ bind(&slow_case);
// Move the undefined value into the result register, which will
// trigger the slow case.
__ Set(temp.reg(), Immediate(Factory::undefined_value()));
__ bind(&end);
frame_->Push(&temp);
}
void CodeGenerator::GenerateIsArray(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
Load(args->at(0));
Result value = frame_->Pop();
value.ToRegister();
ASSERT(value.is_valid());
__ test(value.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(equal);
// It is a heap object - get map.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// Check if the object is a JS array or not.
__ CmpObjectType(value.reg(), JS_ARRAY_TYPE, temp.reg());
value.Unuse();
temp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateIsConstructCall(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
// Get the frame pointer for the calling frame.
Result fp = allocator()->Allocate();
__ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
// Skip the arguments adaptor frame if it exists.
Label check_frame_marker;
__ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(not_equal, &check_frame_marker);
__ mov(fp.reg(), Operand(fp.reg(), StandardFrameConstants::kCallerFPOffset));
// Check the marker in the calling frame.
__ bind(&check_frame_marker);
__ cmp(Operand(fp.reg(), StandardFrameConstants::kMarkerOffset),
Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
fp.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateArgumentsLength(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
// ArgumentsAccessStub takes the parameter count as an input argument
// in register eax. Create a constant result for it.
Result count(Handle<Smi>(Smi::FromInt(scope_->num_parameters())));
// Call the shared stub to get to the arguments.length.
ArgumentsAccessStub stub(ArgumentsAccessStub::READ_LENGTH);
Result result = frame_->CallStub(&stub, &count);
frame_->Push(&result);
}
void CodeGenerator::GenerateClassOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
JumpTarget leave, null, function, non_function_constructor;
Load(args->at(0)); // Load the object.
Result obj = frame_->Pop();
obj.ToRegister();
frame_->Spill(obj.reg());
// If the object is a smi, we return null.
__ test(obj.reg(), Immediate(kSmiTagMask));
null.Branch(zero);
// Check that the object is a JS object but take special care of JS
// functions to make sure they have 'Function' as their class.
{ Result tmp = allocator()->Allocate();
__ mov(obj.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
__ movzx_b(tmp.reg(), FieldOperand(obj.reg(), Map::kInstanceTypeOffset));
__ cmp(tmp.reg(), FIRST_JS_OBJECT_TYPE);
null.Branch(less);
// As long as JS_FUNCTION_TYPE is the last instance type and it is
// right after LAST_JS_OBJECT_TYPE, we can avoid checking for
// LAST_JS_OBJECT_TYPE.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
__ cmp(tmp.reg(), JS_FUNCTION_TYPE);
function.Branch(equal);
}
// Check if the constructor in the map is a function.
{ Result tmp = allocator()->Allocate();
__ mov(obj.reg(), FieldOperand(obj.reg(), Map::kConstructorOffset));
__ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, tmp.reg());
non_function_constructor.Branch(not_equal);
}
// The map register now contains the constructor function. Grab the
// instance class name from there.
__ mov(obj.reg(),
FieldOperand(obj.reg(), JSFunction::kSharedFunctionInfoOffset));
__ mov(obj.reg(),
FieldOperand(obj.reg(), SharedFunctionInfo::kInstanceClassNameOffset));
frame_->Push(&obj);
leave.Jump();
// Functions have class 'Function'.
function.Bind();
frame_->Push(Factory::function_class_symbol());
leave.Jump();
// Objects with a non-function constructor have class 'Object'.
non_function_constructor.Bind();
frame_->Push(Factory::Object_symbol());
leave.Jump();
// Non-JS objects have class null.
null.Bind();
frame_->Push(Factory::null_value());
// All done.
leave.Bind();
}
void CodeGenerator::GenerateValueOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
JumpTarget leave;
Load(args->at(0)); // Load the object.
frame_->Dup();
Result object = frame_->Pop();
object.ToRegister();
ASSERT(object.is_valid());
// if (object->IsSmi()) return object.
__ test(object.reg(), Immediate(kSmiTagMask));
leave.Branch(zero, taken);
// It is a heap object - get map.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
// if (!object->IsJSValue()) return object.
__ CmpObjectType(object.reg(), JS_VALUE_TYPE, temp.reg());
leave.Branch(not_equal, not_taken);
__ mov(temp.reg(), FieldOperand(object.reg(), JSValue::kValueOffset));
object.Unuse();
frame_->SetElementAt(0, &temp);
leave.Bind();
}
void CodeGenerator::GenerateSetValueOf(ZoneList<Expression*>* args) {
ASSERT(args->length() == 2);
JumpTarget leave;
Load(args->at(0)); // Load the object.
Load(args->at(1)); // Load the value.
Result value = frame_->Pop();
Result object = frame_->Pop();
value.ToRegister();
object.ToRegister();
// if (object->IsSmi()) return value.
__ test(object.reg(), Immediate(kSmiTagMask));
leave.Branch(zero, &value, taken);
// It is a heap object - get its map.
Result scratch = allocator_->Allocate();
ASSERT(scratch.is_valid());
// if (!object->IsJSValue()) return value.
__ CmpObjectType(object.reg(), JS_VALUE_TYPE, scratch.reg());
leave.Branch(not_equal, &value, not_taken);
// Store the value.
__ mov(FieldOperand(object.reg(), JSValue::kValueOffset), value.reg());
// Update the write barrier. Save the value as it will be
// overwritten by the write barrier code and is needed afterward.
Result duplicate_value = allocator_->Allocate();
ASSERT(duplicate_value.is_valid());
__ mov(duplicate_value.reg(), value.reg());
// The object register is also overwritten by the write barrier and
// possibly aliased in the frame.
frame_->Spill(object.reg());
__ RecordWrite(object.reg(), JSValue::kValueOffset, duplicate_value.reg(),
scratch.reg());
object.Unuse();
scratch.Unuse();
duplicate_value.Unuse();
// Leave.
leave.Bind(&value);
frame_->Push(&value);
}
void CodeGenerator::GenerateArgumentsAccess(ZoneList<Expression*>* args) {
ASSERT(args->length() == 1);
// ArgumentsAccessStub expects the key in edx and the formal
// parameter count in eax.
Load(args->at(0));
Result key = frame_->Pop();
// Explicitly create a constant result.
Result count(Handle<Smi>(Smi::FromInt(scope_->num_parameters())));
// Call the shared stub to get to arguments[key].
ArgumentsAccessStub stub(ArgumentsAccessStub::READ_ELEMENT);
Result result = frame_->CallStub(&stub, &key, &count);
frame_->Push(&result);
}
void CodeGenerator::GenerateObjectEquals(ZoneList<Expression*>* args) {
ASSERT(args->length() == 2);
// Load the two objects into registers and perform the comparison.
Load(args->at(0));
Load(args->at(1));
Result right = frame_->Pop();
Result left = frame_->Pop();
right.ToRegister();
left.ToRegister();
__ cmp(right.reg(), Operand(left.reg()));
right.Unuse();
left.Unuse();
destination()->Split(equal);
}
void CodeGenerator::GenerateGetFramePointer(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
ASSERT(kSmiTag == 0); // EBP value is aligned, so it should look like Smi.
Result ebp_as_smi = allocator_->Allocate();
ASSERT(ebp_as_smi.is_valid());
__ mov(ebp_as_smi.reg(), Operand(ebp));
frame_->Push(&ebp_as_smi);
}
void CodeGenerator::GenerateRandomPositiveSmi(ZoneList<Expression*>* args) {
ASSERT(args->length() == 0);
frame_->SpillAll();
// Make sure the frame is aligned like the OS expects.
static const int kFrameAlignment = OS::ActivationFrameAlignment();
if (kFrameAlignment > 0) {
ASSERT(IsPowerOf2(kFrameAlignment));
__ mov(edi, Operand(esp)); // Save in callee-saved register.
__ and_(esp, -kFrameAlignment);
}
// Call V8::RandomPositiveSmi().
__ call(FUNCTION_ADDR(V8::RandomPositiveSmi), RelocInfo::RUNTIME_ENTRY);
// Restore stack pointer from callee-saved register edi.
if (kFrameAlignment > 0) {
__ mov(esp, Operand(edi));
}
Result result = allocator_->Allocate(eax);
frame_->Push(&result);
}
void CodeGenerator::GenerateFastMathOp(MathOp op, ZoneList<Expression*>* args) {
JumpTarget done;
JumpTarget call_runtime;
ASSERT(args->length() == 1);
// Load number and duplicate it.
Load(args->at(0));
frame_->Dup();
// Get the number into an unaliased register and load it onto the
// floating point stack still leaving one copy on the frame.
Result number = frame_->Pop();
number.ToRegister();
frame_->Spill(number.reg());
FloatingPointHelper::LoadFloatOperand(masm_, number.reg());
number.Unuse();
// Perform the operation on the number.
switch (op) {
case SIN:
__ fsin();
break;
case COS:
__ fcos();
break;
}
// Go slow case if argument to operation is out of range.
Result eax_reg = allocator_->Allocate(eax);
ASSERT(eax_reg.is_valid());
__ fnstsw_ax();
__ sahf();
eax_reg.Unuse();
call_runtime.Branch(parity_even, not_taken);
// Allocate heap number for result if possible.
Result scratch1 = allocator()->Allocate();
Result scratch2 = allocator()->Allocate();
Result heap_number = allocator()->Allocate();
__ AllocateHeapNumber(heap_number.reg(),
scratch1.reg(),
scratch2.reg(),
call_runtime.entry_label());
scratch1.Unuse();
scratch2.Unuse();
// Store the result in the allocated heap number.
__ fstp_d(FieldOperand(heap_number.reg(), HeapNumber::kValueOffset));
// Replace the extra copy of the argument with the result.
frame_->SetElementAt(0, &heap_number);
done.Jump();
call_runtime.Bind();
// Free ST(0) which was not popped before calling into the runtime.
__ ffree(0);
Result answer;
switch (op) {
case SIN:
answer = frame_->CallRuntime(Runtime::kMath_sin, 1);
break;
case COS:
answer = frame_->CallRuntime(Runtime::kMath_cos, 1);
break;
}
frame_->Push(&answer);
done.Bind();
}
void CodeGenerator::VisitCallRuntime(CallRuntime* node) {
if (CheckForInlineRuntimeCall(node)) {
return;
}
ZoneList<Expression*>* args = node->arguments();
Comment cmnt(masm_, "[ CallRuntime");
Runtime::Function* function = node->function();
if (function == NULL) {
// Prepare stack for calling JS runtime function.
frame_->Push(node->name());
// Push the builtins object found in the current global object.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), GlobalObject());
__ mov(temp.reg(), FieldOperand(temp.reg(), GlobalObject::kBuiltinsOffset));
frame_->Push(&temp);
}
// Push the arguments ("left-to-right").
int arg_count = args->length();
for (int i = 0; i < arg_count; i++) {
Load(args->at(i));
}
if (function == NULL) {
// Call the JS runtime function.
Result answer = frame_->CallCallIC(RelocInfo::CODE_TARGET,
arg_count,
loop_nesting_);
frame_->RestoreContextRegister();
frame_->SetElementAt(0, &answer);
} else {
// Call the C runtime function.
Result answer = frame_->CallRuntime(function, arg_count);
frame_->Push(&answer);
}
}
void CodeGenerator::VisitUnaryOperation(UnaryOperation* node) {
// Note that because of NOT and an optimization in comparison of a typeof
// expression to a literal string, this function can fail to leave a value
// on top of the frame or in the cc register.
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(), NOT_INSIDE_TYPEOF, destination(), true);
// Swap the labels back.
destination()->Invert();
} else if (op == Token::DELETE) {
Property* property = node->expression()->AsProperty();
if (property != NULL) {
Load(property->obj());
Load(property->key());
Result answer = frame_->InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
}
Variable* variable = node->expression()->AsVariableProxy()->AsVariable();
if (variable != NULL) {
Slot* slot = variable->slot();
if (variable->is_global()) {
LoadGlobal();
frame_->Push(variable->name());
Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
} else if (slot != NULL && slot->type() == Slot::LOOKUP) {
// Call the runtime to look up the context holding the named
// variable. Sync the virtual frame eagerly so we can push the
// arguments directly into place.
frame_->SyncRange(0, frame_->element_count() - 1);
frame_->EmitPush(esi);
frame_->EmitPush(Immediate(variable->name()));
Result context = frame_->CallRuntime(Runtime::kLookupContext, 2);
ASSERT(context.is_register());
frame_->EmitPush(context.reg());
context.Unuse();
frame_->EmitPush(Immediate(variable->name()));
Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
CALL_FUNCTION, 2);
frame_->Push(&answer);
return;
}
// Default: Result of deleting non-global, not dynamically
// introduced variables is false.
frame_->Push(Factory::false_value());
} else {
// Default: Result of deleting expressions is true.
Load(node->expression()); // may have side-effects
frame_->SetElementAt(0, Factory::true_value());
}
} else if (op == Token::TYPEOF) {
// Special case for loading the typeof expression; see comment on
// LoadTypeofExpression().
LoadTypeofExpression(node->expression());
Result answer = frame_->CallRuntime(Runtime::kTypeof, 1);
frame_->Push(&answer);
} else if (op == Token::VOID) {
Expression* expression = node->expression();
if (expression && expression->AsLiteral() && (
expression->AsLiteral()->IsTrue() ||
expression->AsLiteral()->IsFalse() ||
expression->AsLiteral()->handle()->IsNumber() ||
expression->AsLiteral()->handle()->IsString() ||
expression->AsLiteral()->handle()->IsJSRegExp() ||
expression->AsLiteral()->IsNull())) {
// Omit evaluating the value of the primitive literal.
// It will be discarded anyway, and can have no side effect.
frame_->Push(Factory::undefined_value());
} else {
Load(node->expression());
frame_->SetElementAt(0, Factory::undefined_value());
}
} else {
Load(node->expression());
switch (op) {
case Token::SUB: {
bool overwrite =
(node->expression()->AsBinaryOperation() != NULL &&
node->expression()->AsBinaryOperation()->ResultOverwriteAllowed());
UnarySubStub stub(overwrite);
// TODO(1222589): remove dependency of TOS being cached inside stub
Result operand = frame_->Pop();
Result answer = frame_->CallStub(&stub, &operand);
frame_->Push(&answer);
break;
}
case Token::BIT_NOT: {
// Smi check.
JumpTarget smi_label;
JumpTarget continue_label;
Result operand = frame_->Pop();
operand.ToRegister();
__ test(operand.reg(), Immediate(kSmiTagMask));
smi_label.Branch(zero, &operand, taken);
frame_->Push(&operand); // undo popping of TOS
Result answer = frame_->InvokeBuiltin(Builtins::BIT_NOT,
CALL_FUNCTION, 1);
continue_label.Jump(&answer);
smi_label.Bind(&answer);
answer.ToRegister();
frame_->Spill(answer.reg());
__ not_(answer.reg());
__ and_(answer.reg(), ~kSmiTagMask); // Remove inverted smi-tag.
continue_label.Bind(&answer);
frame_->Push(&answer);
break;
}
case Token::ADD: {
// Smi check.
JumpTarget continue_label;
Result operand = frame_->Pop();
operand.ToRegister();
__ test(operand.reg(), Immediate(kSmiTagMask));
continue_label.Branch(zero, &operand, taken);
frame_->Push(&operand);
Result answer = frame_->InvokeBuiltin(Builtins::TO_NUMBER,
CALL_FUNCTION, 1);
continue_label.Bind(&answer);
frame_->Push(&answer);
break;
}
default:
// NOT, DELETE, TYPEOF, and VOID are handled outside the
// switch.
UNREACHABLE();
}
}
}
// The value in dst was optimistically incremented or decremented. The
// result overflowed or was not smi tagged. Undo the operation, call
// into the runtime to convert the argument to a number, and call the
// specialized add or subtract stub. The result is left in dst.
class DeferredPrefixCountOperation: public DeferredCode {
public:
DeferredPrefixCountOperation(Register dst, bool is_increment)
: dst_(dst), is_increment_(is_increment) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
bool is_increment_;
};
void DeferredPrefixCountOperation::Generate() {
// Undo the optimistic smi operation.
if (is_increment_) {
__ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
} else {
__ add(Operand(dst_), Immediate(Smi::FromInt(1)));
}
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
__ push(eax);
__ push(Immediate(Smi::FromInt(1)));
if (is_increment_) {
__ CallRuntime(Runtime::kNumberAdd, 2);
} else {
__ CallRuntime(Runtime::kNumberSub, 2);
}
if (!dst_.is(eax)) __ mov(dst_, eax);
}
// The value in dst was optimistically incremented or decremented. The
// result overflowed or was not smi tagged. Undo the operation and call
// into the runtime to convert the argument to a number. Update the
// original value in old. Call the specialized add or subtract stub.
// The result is left in dst.
class DeferredPostfixCountOperation: public DeferredCode {
public:
DeferredPostfixCountOperation(Register dst, Register old, bool is_increment)
: dst_(dst), old_(old), is_increment_(is_increment) {
set_comment("[ DeferredCountOperation");
}
virtual void Generate();
private:
Register dst_;
Register old_;
bool is_increment_;
};
void DeferredPostfixCountOperation::Generate() {
// Undo the optimistic smi operation.
if (is_increment_) {
__ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
} else {
__ add(Operand(dst_), Immediate(Smi::FromInt(1)));
}
__ push(dst_);
__ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
// Save the result of ToNumber to use as the old value.
__ push(eax);
// Call the runtime for the addition or subtraction.
__ push(eax);
__ push(Immediate(Smi::FromInt(1)));
if (is_increment_) {
__ CallRuntime(Runtime::kNumberAdd, 2);
} else {
__ CallRuntime(Runtime::kNumberSub, 2);
}
if (!dst_.is(eax)) __ mov(dst_, eax);
__ pop(old_);
}
void CodeGenerator::VisitCountOperation(CountOperation* node) {
Comment cmnt(masm_, "[ CountOperation");
bool is_postfix = node->is_postfix();
bool is_increment = node->op() == Token::INC;
Variable* var = node->expression()->AsVariableProxy()->AsVariable();
bool is_const = (var != NULL && var->mode() == Variable::CONST);
// Postfix operations need a stack slot under the reference to hold
// the old value while the new value is being stored. This is so that
// in the case that storing the new value requires a call, the old
// value will be in the frame to be spilled.
if (is_postfix) frame_->Push(Smi::FromInt(0));
{ Reference target(this, node->expression());
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(NOT_INSIDE_TYPEOF);
Result new_value = frame_->Pop();
new_value.ToRegister();
Result old_value; // Only allocated in the postfix case.
if (is_postfix) {
// Allocate a temporary to preserve the old value.
old_value = allocator_->Allocate();
ASSERT(old_value.is_valid());
__ mov(old_value.reg(), new_value.reg());
}
// Ensure the new value is writable.
frame_->Spill(new_value.reg());
// In order to combine the overflow and the smi tag check, we need
// to be able to allocate a byte register. We attempt to do so
// without spilling. If we fail, we will generate separate overflow
// and smi tag checks.
//
// We allocate and clear the temporary byte register before
// performing the count operation since clearing the register using
// xor will clear the overflow flag.
Result tmp = allocator_->AllocateByteRegisterWithoutSpilling();
if (tmp.is_valid()) {
__ Set(tmp.reg(), Immediate(0));
}
DeferredCode* deferred = NULL;
if (is_postfix) {
deferred = new DeferredPostfixCountOperation(new_value.reg(),
old_value.reg(),
is_increment);
} else {
deferred = new DeferredPrefixCountOperation(new_value.reg(),
is_increment);
}
if (is_increment) {
__ add(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
} else {
__ sub(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
}
// If the count operation didn't overflow and the result is a valid
// smi, we're done. Otherwise, we jump to the deferred slow-case
// code.
if (tmp.is_valid()) {
// We combine the overflow and the smi tag check if we could
// successfully allocate a temporary byte register.
__ setcc(overflow, tmp.reg());
__ or_(Operand(tmp.reg()), new_value.reg());
__ test(tmp.reg(), Immediate(kSmiTagMask));
tmp.Unuse();
deferred->Branch(not_zero);
} else {
// Otherwise we test separately for overflow and smi tag.
deferred->Branch(overflow);
__ test(new_value.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
}
deferred->BindExit();
// Postfix: store the old value in the allocated slot under the
// reference.
if (is_postfix) frame_->SetElementAt(target.size(), &old_value);
frame_->Push(&new_value);
// Non-constant: update the reference.
if (!is_const) target.SetValue(NOT_CONST_INIT);
}
// Postfix: drop the new value and use the old.
if (is_postfix) frame_->Drop();
}
void CodeGenerator::VisitBinaryOperation(BinaryOperation* node) {
// Note that due to an optimization in comparison operations (typeof
// compared to a string literal), we can evaluate a binary expression such
// as AND or OR and not leave a value on the frame or in the cc register.
Comment cmnt(masm_, "[ BinaryOperation");
Token::Value op = node->op();
// According to ECMA-262 section 11.11, page 58, the binary logical
// operators must yield the result of one of the two expressions
// before any ToBoolean() conversions. This means that the value
// produced by a && or || operator is not necessarily a boolean.
// NOTE: If the left hand side produces a materialized value (not
// control flow), we force the right hand side to do the same. This
// is necessary because we assume that if we get control flow on the
// last path out of an expression we got it on all paths.
if (op == Token::AND) {
JumpTarget is_true;
ControlDestination dest(&is_true, destination()->false_target(), true);
LoadCondition(node->left(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, 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(), NOT_INSIDE_TYPEOF, destination(), false);
} else {
// We have a materialized value on the frame, so we exit with
// one on all paths. There are possibly also jumps to is_true
// from nested subexpressions.
JumpTarget pop_and_continue;
JumpTarget exit;
// Avoid popping the result if it converts to 'false' using the
// standard ToBoolean() conversion as described in ECMA-262,
// section 9.2, page 30.
//
// Duplicate the TOS value. The duplicate will be popped by
// ToBoolean.
frame_->Dup();
ControlDestination dest(&pop_and_continue, &exit, true);
ToBoolean(&dest);
// Pop the result of evaluating the first part.
frame_->Drop();
// Compile right side expression.
is_true.Bind();
Load(node->right());
// Exit (always with a materialized value).
exit.Bind();
}
} else if (op == Token::OR) {
JumpTarget is_false;
ControlDestination dest(destination()->true_target(), &is_false, false);
LoadCondition(node->left(), NOT_INSIDE_TYPEOF, &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(), NOT_INSIDE_TYPEOF, 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(), NOT_INSIDE_TYPEOF, destination(), false);
} else {
// We have a materialized value on the frame, so we exit with
// one on all paths. There are possibly also jumps to is_false
// from nested subexpressions.
JumpTarget pop_and_continue;
JumpTarget exit;
// Avoid popping the result if it converts to 'true' using the
// standard ToBoolean() conversion as described in ECMA-262,
// section 9.2, page 30.
//
// Duplicate the TOS value. The duplicate will be popped by
// ToBoolean.
frame_->Dup();
ControlDestination dest(&exit, &pop_and_continue, false);
ToBoolean(&dest);
// Pop the result of evaluating the first part.
frame_->Drop();
// Compile right side expression.
is_false.Bind();
Load(node->right());
// Exit (always with a materialized value).
exit.Bind();
}
} else {
// NOTE: The code below assumes that the slow cases (calls to runtime)
// never return a constant/immutable object.
OverwriteMode overwrite_mode = NO_OVERWRITE;
if (node->left()->AsBinaryOperation() != NULL &&
node->left()->AsBinaryOperation()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_LEFT;
} else if (node->right()->AsBinaryOperation() != NULL &&
node->right()->AsBinaryOperation()->ResultOverwriteAllowed()) {
overwrite_mode = OVERWRITE_RIGHT;
}
Load(node->left());
Load(node->right());
GenericBinaryOperation(node->op(), node->type(), overwrite_mode);
}
}
void CodeGenerator::VisitThisFunction(ThisFunction* node) {
frame_->PushFunction();
}
void CodeGenerator::VisitCompareOperation(CompareOperation* node) {
Comment cmnt(masm_, "[ CompareOperation");
// Get the expressions from the node.
Expression* left = node->left();
Expression* right = node->right();
Token::Value op = node->op();
// To make typeof testing for natives implemented in JavaScript really
// efficient, we generate special code for expressions of the form:
// 'typeof <expression> == <string>'.
UnaryOperation* operation = left->AsUnaryOperation();
if ((op == Token::EQ || op == Token::EQ_STRICT) &&
(operation != NULL && operation->op() == Token::TYPEOF) &&
(right->AsLiteral() != NULL &&
right->AsLiteral()->handle()->IsString())) {
Handle<String> check(String::cast(*right->AsLiteral()->handle()));
// Load the operand and move it to a register.
LoadTypeofExpression(operation->expression());
Result answer = frame_->Pop();
answer.ToRegister();
if (check->Equals(Heap::number_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->true_target()->Branch(zero);
frame_->Spill(answer.reg());
__ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ cmp(answer.reg(), Factory::heap_number_map());
answer.Unuse();
destination()->Split(equal);
} else if (check->Equals(Heap::string_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
// It can be an undetectable string object.
Result temp = allocator()->Allocate();
ASSERT(temp.is_valid());
__ mov(temp.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kBitFieldOffset));
__ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
destination()->false_target()->Branch(not_zero);
__ mov(temp.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(temp.reg(),
FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
__ cmp(temp.reg(), FIRST_NONSTRING_TYPE);
temp.Unuse();
answer.Unuse();
destination()->Split(less);
} else if (check->Equals(Heap::boolean_symbol())) {
__ cmp(answer.reg(), Factory::true_value());
destination()->true_target()->Branch(equal);
__ cmp(answer.reg(), Factory::false_value());
answer.Unuse();
destination()->Split(equal);
} else if (check->Equals(Heap::undefined_symbol())) {
__ cmp(answer.reg(), Factory::undefined_value());
destination()->true_target()->Branch(equal);
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
// It can be an undetectable object.
frame_->Spill(answer.reg());
__ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(answer.reg(),
FieldOperand(answer.reg(), Map::kBitFieldOffset));
__ test(answer.reg(), Immediate(1 << Map::kIsUndetectable));
answer.Unuse();
destination()->Split(not_zero);
} else if (check->Equals(Heap::function_symbol())) {
__ test(answer.reg(), Immediate(kSmiTagMask));
destination()->false_target()->Branch(zero);
frame_->Spill(answer.reg());
__ CmpObjectType(answer.reg(), JS_FUNCTION_TYPE, answer.reg());
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);
// It can be an undetectable object.
Result map = allocator()->Allocate();
ASSERT(map.is_valid());
__ mov(map.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kBitFieldOffset));
__ test(map.reg(), Immediate(1 << Map::kIsUndetectable));
destination()->false_target()->Branch(not_zero);
__ mov(map.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
__ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
__ cmp(map.reg(), FIRST_JS_OBJECT_TYPE);
destination()->false_target()->Branch(less);
__ cmp(map.reg(), LAST_JS_OBJECT_TYPE);
answer.Unuse();
map.Unuse();
destination()->Split(less_equal);
} else {
// Uncommon case: typeof testing against a string literal that is
// never returned from the typeof operator.
answer.Unuse();
destination()->Goto(false);
}
return;
}
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: {
Load(left);
Load(right);
Result answer = frame_->InvokeBuiltin(Builtins::IN, CALL_FUNCTION, 2);
frame_->Push(&answer); // push the result
return;
}
case Token::INSTANCEOF: {
Load(left);
Load(right);
InstanceofStub stub;
Result answer = frame_->CallStub(&stub, 2);
answer.ToRegister();
__ test(answer.reg(), Operand(answer.reg()));
answer.Unuse();
destination()->Split(zero);
return;
}
default:
UNREACHABLE();
}
Load(left);
Load(right);
Comparison(cc, strict, destination());
}
#ifdef DEBUG
bool CodeGenerator::HasValidEntryRegisters() {
return (allocator()->count(eax) == (frame()->is_used(eax) ? 1 : 0))
&& (allocator()->count(ebx) == (frame()->is_used(ebx) ? 1 : 0))
&& (allocator()->count(ecx) == (frame()->is_used(ecx) ? 1 : 0))
&& (allocator()->count(edx) == (frame()->is_used(edx) ? 1 : 0))
&& (allocator()->count(edi) == (frame()->is_used(edi) ? 1 : 0));
}
#endif
// Emit a LoadIC call to get the value from receiver and leave it in
// dst. The receiver register is restored after the call.
class DeferredReferenceGetNamedValue: public DeferredCode {
public:
DeferredReferenceGetNamedValue(Register dst,
Register receiver,
Handle<String> name)
: dst_(dst), receiver_(receiver), name_(name) {
set_comment("[ DeferredReferenceGetNamedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Label patch_site_;
Register dst_;
Register receiver_;
Handle<String> name_;
};
void DeferredReferenceGetNamedValue::Generate() {
__ push(receiver_);
__ Set(ecx, Immediate(name_));
Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
__ call(ic, RelocInfo::CODE_TARGET);
// The call must be followed by a test eax instruction to indicate
// that the inobject property case was inlined.
//
// Store the delta to the map check instruction here in the test
// instruction. Use masm_-> instead of the __ macro since the
// latter can't return a value.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
// Here we use masm_-> instead of the __ macro because this is the
// instruction that gets patched and coverage code gets in the way.
masm_->test(eax, Immediate(-delta_to_patch_site));
__ IncrementCounter(&Counters::named_load_inline_miss, 1);
if (!dst_.is(eax)) __ mov(dst_, eax);
__ pop(receiver_);
}
class DeferredReferenceGetKeyedValue: public DeferredCode {
public:
explicit DeferredReferenceGetKeyedValue(Register dst,
Register receiver,
Register key,
bool is_global)
: dst_(dst), receiver_(receiver), key_(key), is_global_(is_global) {
set_comment("[ DeferredReferenceGetKeyedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Label patch_site_;
Register dst_;
Register receiver_;
Register key_;
bool is_global_;
};
void DeferredReferenceGetKeyedValue::Generate() {
__ push(receiver_); // First IC argument.
__ push(key_); // Second IC argument.
// 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));
RelocInfo::Mode mode = is_global_
? RelocInfo::CODE_TARGET_CONTEXT
: RelocInfo::CODE_TARGET;
__ call(ic, mode);
// 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);
__ pop(key_);
__ pop(receiver_);
}
class DeferredReferenceSetKeyedValue: public DeferredCode {
public:
DeferredReferenceSetKeyedValue(Register value,
Register key,
Register receiver)
: value_(value), key_(key), receiver_(receiver) {
set_comment("[ DeferredReferenceSetKeyedValue");
}
virtual void Generate();
Label* patch_site() { return &patch_site_; }
private:
Register value_;
Register key_;
Register receiver_;
Label patch_site_;
};
void DeferredReferenceSetKeyedValue::Generate() {
__ IncrementCounter(&Counters::keyed_store_inline_miss, 1);
// Push receiver and key arguments on the stack.
__ push(receiver_);
__ push(key_);
// Move value argument to eax as expected by the IC stub.
if (!value_.is(eax)) __ mov(eax, value_);
// Call the IC stub.
Handle<Code> ic(Builtins::builtin(Builtins::KeyedStoreIC_Initialize));
__ call(ic, RelocInfo::CODE_TARGET);
// The delta from the start of the map-compare instruction to the
// test instruction. We use masm_-> directly here instead of the
// __ macro because the macro sometimes uses macro expansion to turn
// into something that can't return a value. This is encountered
// when doing generated code coverage tests.
int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
// Here we use masm_-> instead of the __ macro because this is the
// instruction that gets patched and coverage code gets in the way.
masm_->test(eax, Immediate(-delta_to_patch_site));
// Restore value (returned from store IC), key and receiver
// registers.
if (!value_.is(eax)) __ mov(value_, eax);
__ pop(key_);
__ pop(receiver_);
}
#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>(String::cast(*raw_name->handle()));
}
}
void Reference::GetValue(TypeofState typeof_state) {
ASSERT(!cgen_->in_spilled_code());
ASSERT(cgen_->HasValidEntryRegisters());
ASSERT(!is_illegal());
MacroAssembler* masm = cgen_->masm();
// Record the source position for the property load.
Property* property = expression_->AsProperty();
if (property != NULL) {
cgen_->CodeForSourcePosition(property->position());
}
switch (type_) {
case SLOT: {
Comment cmnt(masm, "[ Load from Slot");
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
cgen_->LoadFromSlotCheckForArguments(slot, typeof_state);
break;
}
case NAMED: {
// TODO(1241834): Make sure that it is safe to ignore the
// distinction between expressions in a typeof and not in a
// typeof. If there is a chance that reference errors can be
// thrown below, we must distinguish between the two kinds of
// loads (typeof expression loads must not throw a reference
// error).
Variable* var = expression_->AsVariableProxy()->AsVariable();
bool is_global = var != NULL;
ASSERT(!is_global || var->is_global());
// Do not inline the inobject property case for loads from the global
// object. Also do not inline for unoptimized code. This saves time
// in the code generator. Unoptimized code is toplevel code or code
// that is not in a loop.
if (is_global ||
cgen_->scope()->is_global_scope() ||
cgen_->loop_nesting() == 0) {
Comment cmnt(masm, "[ Load from named Property");
cgen_->frame()->Push(GetName());
RelocInfo::Mode mode = is_global
? RelocInfo::CODE_TARGET_CONTEXT
: RelocInfo::CODE_TARGET;
Result answer = cgen_->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();
cgen_->frame()->Push(&answer);
} else {
// Inline the inobject property case.
Comment cmnt(masm, "[ Inlined named property load");
Result receiver = cgen_->frame()->Pop();
receiver.ToRegister();
Result value = cgen_->allocator()->Allocate();
ASSERT(value.is_valid());
DeferredReferenceGetNamedValue* deferred =
new DeferredReferenceGetNamedValue(value.reg(),
receiver.reg(),
GetName());
// Check that the receiver is a heap object.
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
__ bind(deferred->patch_site());
// This is the map check instruction that will be patched (so we can't
// use the double underscore macro that may insert instructions).
// Initially use an invalid map to force a failure.
masm->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
Immediate(Factory::null_value()));
// This branch is always a forwards branch so it's always a fixed
// size which allows the assert below to succeed and patching to work.
deferred->Branch(not_equal);
// The delta from the patch label to the load offset must be
// statically known.
ASSERT(masm->SizeOfCodeGeneratedSince(deferred->patch_site()) ==
LoadIC::kOffsetToLoadInstruction);
// The initial (invalid) offset has to be large enough to force
// a 32-bit instruction encoding to allow patching with an
// arbitrary offset. Use kMaxInt (minus kHeapObjectTag).
int offset = kMaxInt;
masm->mov(value.reg(), FieldOperand(receiver.reg(), offset));
__ IncrementCounter(&Counters::named_load_inline, 1);
deferred->BindExit();
cgen_->frame()->Push(&receiver);
cgen_->frame()->Push(&value);
}
break;
}
case KEYED: {
// TODO(1241834): Make sure that this it is safe to ignore the
// distinction between expressions in a typeof and not in a typeof.
Comment cmnt(masm, "[ Load from keyed Property");
Variable* var = expression_->AsVariableProxy()->AsVariable();
bool is_global = var != NULL;
ASSERT(!is_global || var->is_global());
// 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 (cgen_->loop_nesting() > 0) {
Comment cmnt(masm, "[ Inlined load from keyed Property");
Result key = cgen_->frame()->Pop();
Result receiver = cgen_->frame()->Pop();
key.ToRegister();
receiver.ToRegister();
// Use a fresh temporary to load the elements without destroying
// the receiver which is needed for the deferred slow case.
Result elements = cgen_->allocator()->Allocate();
ASSERT(elements.is_valid());
// Use a fresh temporary for the index and later the loaded
// value.
Result index = cgen_->allocator()->Allocate();
ASSERT(index.is_valid());
DeferredReferenceGetKeyedValue* deferred =
new DeferredReferenceGetKeyedValue(index.reg(),
receiver.reg(),
key.reg(),
is_global);
// Check that the receiver is not a smi (only needed if this
// is not a load from the global context) and that it has the
// expected map.
if (!is_global) {
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
}
// Initially, use an invalid map. The map is patched in the IC
// initialization code.
__ bind(deferred->patch_site());
// Use masm-> here instead of the double underscore macro since extra
// coverage code can interfere with the patching.
masm->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
Immediate(Factory::null_value()));
deferred->Branch(not_equal);
// Check that the key is a smi.
__ test(key.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
// Get the elements array from the receiver and check that it
// is not a dictionary.
__ mov(elements.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
__ cmp(FieldOperand(elements.reg(), HeapObject::kMapOffset),
Immediate(Factory::fixed_array_map()));
deferred->Branch(not_equal);
// Shift the key to get the actual index value and check that
// it is within bounds.
__ mov(index.reg(), key.reg());
__ sar(index.reg(), kSmiTagSize);
__ cmp(index.reg(),
FieldOperand(elements.reg(), FixedArray::kLengthOffset));
deferred->Branch(above_equal);
// Load and check that the result is not the hole. We could
// reuse the index or elements register for the value.
//
// TODO(206): Consider whether it makes sense to try some
// heuristic about which register to reuse. For example, if
// one is eax, the we can reuse that one because the value
// coming from the deferred code will be in eax.
Result value = index;
__ mov(value.reg(), Operand(elements.reg(),
index.reg(),
times_4,
FixedArray::kHeaderSize - kHeapObjectTag));
elements.Unuse();
index.Unuse();
__ cmp(Operand(value.reg()), Immediate(Factory::the_hole_value()));
deferred->Branch(equal);
__ IncrementCounter(&Counters::keyed_load_inline, 1);
deferred->BindExit();
// Restore the receiver and key to the frame and push the
// result on top of it.
cgen_->frame()->Push(&receiver);
cgen_->frame()->Push(&key);
cgen_->frame()->Push(&value);
} else {
Comment cmnt(masm, "[ Load from keyed Property");
RelocInfo::Mode mode = is_global
? RelocInfo::CODE_TARGET_CONTEXT
: RelocInfo::CODE_TARGET;
Result answer = cgen_->frame()->CallKeyedLoadIC(mode);
// 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();
cgen_->frame()->Push(&answer);
}
break;
}
default:
UNREACHABLE();
}
}
void Reference::TakeValue(TypeofState typeof_state) {
// 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(typeof_state);
return;
}
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
if (slot->type() == Slot::LOOKUP ||
slot->type() == Slot::CONTEXT ||
slot->var()->mode() == Variable::CONST ||
slot->is_arguments()) {
GetValue(typeof_state);
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());
}
}
void Reference::SetValue(InitState init_state) {
ASSERT(cgen_->HasValidEntryRegisters());
ASSERT(!is_illegal());
MacroAssembler* masm = cgen_->masm();
switch (type_) {
case SLOT: {
Comment cmnt(masm, "[ Store to Slot");
Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
ASSERT(slot != NULL);
cgen_->StoreToSlot(slot, init_state);
break;
}
case NAMED: {
Comment cmnt(masm, "[ Store to named Property");
cgen_->frame()->Push(GetName());
Result answer = cgen_->frame()->CallStoreIC();
cgen_->frame()->Push(&answer);
break;
}
case KEYED: {
Comment cmnt(masm, "[ Store to keyed Property");
// Generate inlined version of the keyed store if the code is in
// a loop and the key is likely to be a smi.
Property* property = expression()->AsProperty();
ASSERT(property != NULL);
SmiAnalysis* key_smi_analysis = property->key()->type();
if (cgen_->loop_nesting() > 0 && key_smi_analysis->IsLikelySmi()) {
Comment cmnt(masm, "[ Inlined store to keyed Property");
// Get the receiver, key and value into registers.
Result value = cgen_->frame()->Pop();
Result key = cgen_->frame()->Pop();
Result receiver = cgen_->frame()->Pop();
Result tmp = cgen_->allocator_->Allocate();
ASSERT(tmp.is_valid());
// Determine whether the value is a constant before putting it
// in a register.
bool value_is_constant = value.is_constant();
// Make sure that value, key and receiver are in registers.
value.ToRegister();
key.ToRegister();
receiver.ToRegister();
DeferredReferenceSetKeyedValue* deferred =
new DeferredReferenceSetKeyedValue(value.reg(),
key.reg(),
receiver.reg());
// Check that the value is a smi if it is not a constant. We
// can skip the write barrier for smis and constants.
if (!value_is_constant) {
__ test(value.reg(), Immediate(kSmiTagMask));
deferred->Branch(not_zero);
}
// Check that the key is a non-negative smi.
__ test(key.reg(), Immediate(kSmiTagMask | 0x80000000));
deferred->Branch(not_zero);
// Check that the receiver is not a smi.
__ test(receiver.reg(), Immediate(kSmiTagMask));
deferred->Branch(zero);
// Check that the receiver is a JSArray.
__ mov(tmp.reg(),
FieldOperand(receiver.reg(), HeapObject::kMapOffset));
__ movzx_b(tmp.reg(),
FieldOperand(tmp.reg(), Map::kInstanceTypeOffset));
__ cmp(tmp.reg(), JS_ARRAY_TYPE);
deferred->Branch(not_equal);
// Check that the key is within bounds. Both the key and the
// length of the JSArray are smis.
__ cmp(key.reg(),
FieldOperand(receiver.reg(), JSArray::kLengthOffset));
deferred->Branch(greater_equal);
// Get the elements array from the receiver and check that it
// is not a dictionary.
__ mov(tmp.reg(),
FieldOperand(receiver.reg(), JSObject::kElementsOffset));
// Bind the deferred code patch site to be able to locate the
// fixed array map comparison. When debugging, we patch this
// comparison to always fail so that we will hit the IC call
// in the deferred code which will allow the debugger to
// break for fast case stores.
__ bind(deferred->patch_site());
__ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
Immediate(Factory::fixed_array_map()));
deferred->Branch(not_equal);
// Store the value.
__ mov(Operand(tmp.reg(),
key.reg(),
times_2,
FixedArray::kHeaderSize - kHeapObjectTag),
value.reg());
__ IncrementCounter(&Counters::keyed_store_inline, 1);
deferred->BindExit();
cgen_->frame()->Push(&receiver);
cgen_->frame()->Push(&key);
cgen_->frame()->Push(&value);
} else {
Result answer = cgen_->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();
cgen_->frame()->Push(&answer);
}
break;
}
default:
UNREACHABLE();
}
}
// NOTE: The stub does not handle the inlined cases (Smis, Booleans, undefined).
void ToBooleanStub::Generate(MacroAssembler* masm) {
Label false_result, true_result, not_string;
__ mov(eax, Operand(esp, 1 * kPointerSize));
// 'null' => false.
__ cmp(eax, Factory::null_value());
__ j(equal, &false_result);
// Get the map and type of the heap object.
__ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(edx, Map::kInstanceTypeOffset));
// Undetectable => false.
__ movzx_b(ebx, FieldOperand(edx, Map::kBitFieldOffset));
__ and_(ebx, 1 << Map::kIsUndetectable);
__ j(not_zero, &false_result);
// JavaScript object => true.
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(above_equal, &true_result);
// String value => false iff empty.
__ cmp(ecx, FIRST_NONSTRING_TYPE);
__ j(above_equal, ¬_string);
__ and_(ecx, kStringSizeMask);
__ cmp(ecx, kShortStringTag);
__ j(not_equal, &true_result); // Empty string is always short.
__ mov(edx, FieldOperand(eax, String::kLengthOffset));
__ shr(edx, String::kShortLengthShift);
__ j(zero, &false_result);
__ jmp(&true_result);
__ bind(¬_string);
// HeapNumber => false iff +0, -0, or NaN.
__ cmp(edx, Factory::heap_number_map());
__ j(not_equal, &true_result);
__ fldz();
__ fld_d(FieldOperand(eax, HeapNumber::kValueOffset));
__ FCmp();
__ j(zero, &false_result);
// Fall through to |true_result|.
// Return 1/0 for true/false in eax.
__ bind(&true_result);
__ mov(eax, 1);
__ ret(1 * kPointerSize);
__ bind(&false_result);
__ mov(eax, 0);
__ ret(1 * kPointerSize);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Register left,
Register right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(left);
__ push(right);
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (!(left.is(left_arg) && right.is(right_arg))) {
if (left.is(right_arg) && right.is(left_arg)) {
if (IsOperationCommutative()) {
SetArgsReversed();
} else {
__ xchg(left, right);
}
} else if (left.is(left_arg)) {
__ mov(right_arg, right);
} else if (left.is(right_arg)) {
if (IsOperationCommutative()) {
__ mov(left_arg, right);
SetArgsReversed();
} else {
// Order of moves important to avoid destroying left argument.
__ mov(left_arg, left);
__ mov(right_arg, right);
}
} else if (right.is(left_arg)) {
if (IsOperationCommutative()) {
__ mov(right_arg, left);
SetArgsReversed();
} else {
// Order of moves important to avoid destroying right argument.
__ mov(right_arg, right);
__ mov(left_arg, left);
}
} else if (right.is(right_arg)) {
__ mov(left_arg, left);
} else {
// Order of moves is not important.
__ mov(left_arg, left);
__ mov(right_arg, right);
}
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Register left,
Smi* right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(left);
__ push(Immediate(right));
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (left.is(left_arg)) {
__ mov(right_arg, Immediate(right));
} else if (left.is(right_arg) && IsOperationCommutative()) {
__ mov(left_arg, Immediate(right));
SetArgsReversed();
} else {
__ mov(left_arg, left);
__ mov(right_arg, Immediate(right));
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
void GenericBinaryOpStub::GenerateCall(
MacroAssembler* masm,
Smi* left,
Register right) {
if (!ArgsInRegistersSupported()) {
// Pass arguments on the stack.
__ push(Immediate(left));
__ push(right);
} else {
// The calling convention with registers is left in edx and right in eax.
Register left_arg = edx;
Register right_arg = eax;
if (right.is(right_arg)) {
__ mov(left_arg, Immediate(left));
} else if (right.is(left_arg) && IsOperationCommutative()) {
__ mov(right_arg, Immediate(left));
SetArgsReversed();
} else {
__ mov(left_arg, Immediate(left));
__ mov(right_arg, right);
}
// Update flags to indicate that arguments are in registers.
SetArgsInRegisters();
__ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1);
}
// Call the stub.
__ CallStub(this);
}
void GenericBinaryOpStub::GenerateSmiCode(MacroAssembler* masm, Label* slow) {
// Perform fast-case smi code for the operation (eax <op> ebx) and
// leave result in register eax.
// Prepare the smi check of both operands by or'ing them together
// before checking against the smi mask.
__ mov(ecx, Operand(ebx));
__ or_(ecx, Operand(eax));
switch (op_) {
case Token::ADD:
__ add(eax, Operand(ebx)); // add optimistically
__ j(overflow, slow, not_taken);
break;
case Token::SUB:
__ sub(eax, Operand(ebx)); // subtract optimistically
__ j(overflow, slow, not_taken);
break;
case Token::DIV:
case Token::MOD:
// Sign extend eax into edx:eax.
__ cdq();
// Check for 0 divisor.
__ test(ebx, Operand(ebx));
__ j(zero, slow, not_taken);
break;
default:
// Fall-through to smi check.
break;
}
// Perform the actual smi check.
ASSERT(kSmiTag == 0); // adjust zero check if not the case
__ test(ecx, Immediate(kSmiTagMask));
__ j(not_zero, slow, not_taken);
switch (op_) {
case Token::ADD:
case Token::SUB:
// Do nothing here.
break;
case Token::MUL:
// If the smi tag is 0 we can just leave the tag on one operand.
ASSERT(kSmiTag == 0); // adjust code below if not the case
// Remove tag from one of the operands (but keep sign).
__ sar(eax, kSmiTagSize);
// Do multiplication.
__ imul(eax, Operand(ebx)); // multiplication of smis; result in eax
// Go slow on overflows.
__ j(overflow, slow, not_taken);
// Check for negative zero result.
__ NegativeZeroTest(eax, ecx, slow); // use ecx = x | y
break;
case Token::DIV:
// Divide edx:eax by ebx.
__ idiv(ebx);
// Check for the corner case of dividing the most negative smi
// by -1. We cannot use the overflow flag, since it is not set
// by idiv instruction.
ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
__ cmp(eax, 0x40000000);
__ j(equal, slow);
// Check for negative zero result.
__ NegativeZeroTest(eax, ecx, slow); // use ecx = x | y
// Check that the remainder is zero.
__ test(edx, Operand(edx));
__ j(not_zero, slow);
// Tag the result and store it in register eax.
ASSERT(kSmiTagSize == times_2); // adjust code if not the case
__ lea(eax, Operand(eax, eax, times_1, kSmiTag));
break;
case Token::MOD:
// Divide edx:eax by ebx.
__ idiv(ebx);
// Check for negative zero result.
__ NegativeZeroTest(edx, ecx, slow); // use ecx = x | y
// Move remainder to register eax.
__ mov(eax, Operand(edx));
break;
case Token::BIT_OR:
__ or_(eax, Operand(ebx));
break;
case Token::BIT_AND:
__ and_(eax, Operand(ebx));
break;
case Token::BIT_XOR:
__ xor_(eax, Operand(ebx));
break;
case Token::SHL:
case Token::SHR:
case Token::SAR:
// Move the second operand into register ecx.
__ mov(ecx, Operand(ebx));
// Remove tags from operands (but keep sign).
__ sar(eax, kSmiTagSize);
__ sar(ecx, kSmiTagSize);
// Perform the operation.
switch (op_) {
case Token::SAR:
__ sar(eax);
// No checks of result necessary
break;
case Token::SHR:
__ shr(eax);
// Check that the *unsigned* result fits in a smi.
// Neither of the two high-order bits can be set:
// - 0x80000000: high bit would be lost when smi tagging.
// - 0x40000000: this number would convert to negative when
// Smi tagging these two cases can only happen with shifts
// by 0 or 1 when handed a valid smi.
__ test(eax, Immediate(0xc0000000));
__ j(not_zero, slow, not_taken);
break;
case Token::SHL:
__ shl(eax);
// Check that the *signed* result fits in a smi.
__ cmp(eax, 0xc0000000);
__ j(sign, slow, not_taken);
break;
default:
UNREACHABLE();
}
// Tag the result and store it in register eax.
ASSERT(kSmiTagSize == times_2); // adjust code if not the case
__ lea(eax, Operand(eax, eax, times_1, kSmiTag));
break;
default:
UNREACHABLE();
break;
}
}
void GenericBinaryOpStub::Generate(MacroAssembler* masm) {
Label call_runtime;
__ IncrementCounter(&Counters::generic_binary_stub_calls, 1);
// Generate fast case smi code if requested. This flag is set when the fast
// case smi code is not generated by the caller. Generating it here will speed
// up common operations.
if (HasSmiCodeInStub()) {
Label slow;
__ mov(ebx, Operand(esp, 1 * kPointerSize));
__ mov(eax, Operand(esp, 2 * kPointerSize));
GenerateSmiCode(masm, &slow);
GenerateReturn(masm);
// Too bad. The fast case smi code didn't succeed.
__ bind(&slow);
}
// Make sure the arguments are in edx and eax.
GenerateLoadArguments(masm);
// Floating point case.
switch (op_) {
case Token::ADD:
case Token::SUB:
case Token::MUL:
case Token::DIV: {
// eax: y
// edx: x
if (CpuFeatures::IsSupported(CpuFeatures::SSE2)) {
CpuFeatures::Scope use_sse2(CpuFeatures::SSE2);
FloatingPointHelper::LoadSse2Operands(masm, &call_runtime);
switch (op_) {
case Token::ADD: __ addsd(xmm0, xmm1); break;
case Token::SUB: __ subsd(xmm0, xmm1); break;
case Token::MUL: __ mulsd(xmm0, xmm1); break;
case Token::DIV: __ divsd(xmm0, xmm1); break;
default: UNREACHABLE();
}
// Allocate a heap number, if needed.
Label skip_allocation;
switch (mode_) {
case OVERWRITE_LEFT:
__ mov(eax, Operand(edx));
// Fall through!
case OVERWRITE_RIGHT:
// If the argument in eax is already an object, we skip the
// allocation of a heap number.
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Fall through!
case NO_OVERWRITE: {
// Allocate a heap number for the result. Keep eax and edx intact
// for the possible runtime call.
__ AllocateHeapNumber(ebx, ecx, no_reg, &call_runtime);
// Now eax can be overwritten losing one of the arguments as we are
// now done and will not need it any more.
__ mov(eax, ebx);
__ bind(&skip_allocation);
break;
}
default: UNREACHABLE();
}
__ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
GenerateReturn(masm);
} else { // SSE2 not available, use FPU.
FloatingPointHelper::CheckFloatOperands(masm, &call_runtime, ebx);
// Allocate a heap number, if needed.
Label skip_allocation;
switch (mode_) {
case OVERWRITE_LEFT:
__ mov(eax, Operand(edx));
// Fall through!
case OVERWRITE_RIGHT:
// If the argument in eax is already an object, we skip the
// allocation of a heap number.
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Fall through!
case NO_OVERWRITE:
// Allocate a heap number for the result. Keep eax and edx intact
// for the possible runtime call.
__ AllocateHeapNumber(ebx, ecx, no_reg, &call_runtime);
// Now eax can be overwritten losing one of the arguments as we are
// now done and will not need it any more.
__ mov(eax, ebx);
__ bind(&skip_allocation);
break;
default: UNREACHABLE();
}
FloatingPointHelper::LoadFloatOperands(masm, ecx);
switch (op_) {
case Token::ADD: __ faddp(1); break;
case Token::SUB: __ fsubp(1); break;
case Token::MUL: __ fmulp(1); break;
case Token::DIV: __ fdivp(1); break;
default: UNREACHABLE();
}
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
GenerateReturn(masm);
}
}
case Token::MOD: {
// For MOD we go directly to runtime in the non-smi case.
break;
}
case Token::BIT_OR:
case Token::BIT_AND:
case Token::BIT_XOR:
case Token::SAR:
case Token::SHL:
case Token::SHR: {
FloatingPointHelper::CheckFloatOperands(masm, &call_runtime, ebx);
FloatingPointHelper::LoadFloatOperands(masm, ecx);
Label skip_allocation, non_smi_result, operand_conversion_failure;
// Reserve space for converted numbers.
__ sub(Operand(esp), Immediate(2 * kPointerSize));
if (use_sse3_) {
// Truncate the operands to 32-bit integers and check for
// exceptions in doing so.
CpuFeatures::Scope scope(CpuFeatures::SSE3);
__ fisttp_s(Operand(esp, 0 * kPointerSize));
__ fisttp_s(Operand(esp, 1 * kPointerSize));
__ fnstsw_ax();
__ test(eax, Immediate(1));
__ j(not_zero, &operand_conversion_failure);
} else {
// Check if right operand is int32.
__ fist_s(Operand(esp, 0 * kPointerSize));
__ fild_s(Operand(esp, 0 * kPointerSize));
__ FCmp();
__ j(not_zero, &operand_conversion_failure);
__ j(parity_even, &operand_conversion_failure);
// Check if left operand is int32.
__ fist_s(Operand(esp, 1 * kPointerSize));
__ fild_s(Operand(esp, 1 * kPointerSize));
__ FCmp();
__ j(not_zero, &operand_conversion_failure);
__ j(parity_even, &operand_conversion_failure);
}
// Get int32 operands and perform bitop.
__ pop(ecx);
__ pop(eax);
switch (op_) {
case Token::BIT_OR: __ or_(eax, Operand(ecx)); break;
case Token::BIT_AND: __ and_(eax, Operand(ecx)); break;
case Token::BIT_XOR: __ xor_(eax, Operand(ecx)); break;
case Token::SAR: __ sar(eax); break;
case Token::SHL: __ shl(eax); break;
case Token::SHR: __ shr(eax); break;
default: UNREACHABLE();
}
if (op_ == Token::SHR) {
// Check if result is non-negative and fits in a smi.
__ test(eax, Immediate(0xc0000000));
__ j(not_zero, &non_smi_result);
} else {
// Check if result fits in a smi.
__ cmp(eax, 0xc0000000);
__ j(negative, &non_smi_result);
}
// Tag smi result and return.
ASSERT(kSmiTagSize == times_2); // adjust code if not the case
__ lea(eax, Operand(eax, eax, times_1, kSmiTag));
GenerateReturn(masm);
// All ops except SHR return a signed int32 that we load in a HeapNumber.
if (op_ != Token::SHR) {
__ bind(&non_smi_result);
// Allocate a heap number if needed.
__ mov(ebx, Operand(eax)); // ebx: result
switch (mode_) {
case OVERWRITE_LEFT:
case OVERWRITE_RIGHT:
// If the operand was an object, we skip the
// allocation of a heap number.
__ mov(eax, Operand(esp, mode_ == OVERWRITE_RIGHT ?
1 * kPointerSize : 2 * kPointerSize));
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &skip_allocation, not_taken);
// Fall through!
case NO_OVERWRITE:
__ AllocateHeapNumber(eax, ecx, edx, &call_runtime);
__ bind(&skip_allocation);
break;
default: UNREACHABLE();
}
// Store the result in the HeapNumber and return.
__ mov(Operand(esp, 1 * kPointerSize), ebx);
__ fild_s(Operand(esp, 1 * kPointerSize));
__ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
GenerateReturn(masm);
}
// Clear the FPU exception flag and reset the stack before calling
// the runtime system.
__ bind(&operand_conversion_failure);
__ add(Operand(esp), Immediate(2 * kPointerSize));
if (use_sse3_) {
// If we've used the SSE3 instructions for truncating the
// floating point values to integers and it failed, we have a
// pending #IA exception. Clear it.
__ fnclex();
} else {
// The non-SSE3 variant does early bailout if the right
// operand isn't a 32-bit integer, so we may have a single
// value on the FPU stack we need to get rid of.
__ ffree(0);
}
// SHR should return uint32 - go to runtime for non-smi/negative result.
if (op_ == Token::SHR) {
__ bind(&non_smi_result);
}
__ mov(eax, Operand(esp, 1 * kPointerSize));
__ mov(edx, Operand(esp, 2 * kPointerSize));
break;
}
default: UNREACHABLE(); break;
}
// If all else fails, use the runtime system to get the correct
// result. If arguments was passed in registers now place them on the
// stack in the correct order below the return address.
__ bind(&call_runtime);
if (HasArgumentsInRegisters()) {
__ pop(ecx);
if (HasArgumentsReversed()) {
__ push(eax);
__ push(edx);
} else {
__ push(edx);
__ push(eax);
}
__ push(ecx);
}
switch (op_) {
case Token::ADD: {
// Test for string arguments before calling runtime.
Label not_strings, both_strings, not_string1, string1;
Result answer;
__ mov(eax, Operand(esp, 2 * kPointerSize)); // First argument.
__ mov(edx, Operand(esp, 1 * kPointerSize)); // Second argument.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, ¬_string1);
__ CmpObjectType(eax, FIRST_NONSTRING_TYPE, eax);
__ j(above_equal, ¬_string1);
// First argument is a a string, test second.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &string1);
__ CmpObjectType(edx, FIRST_NONSTRING_TYPE, edx);
__ j(above_equal, &string1);
// First and second argument are strings.
__ TailCallRuntime(ExternalReference(Runtime::kStringAdd), 2, 1);
// Only first argument is a string.
__ bind(&string1);
__ InvokeBuiltin(Builtins::STRING_ADD_LEFT, JUMP_FUNCTION);
// First argument was not a string, test second.
__ bind(¬_string1);
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, ¬_strings);
__ CmpObjectType(edx, FIRST_NONSTRING_TYPE, edx);
__ j(above_equal, ¬_strings);
// Only second argument is a string.
__ InvokeBuiltin(Builtins::STRING_ADD_RIGHT, JUMP_FUNCTION);
__ bind(¬_strings);
// Neither argument is a string.
__ InvokeBuiltin(Builtins::ADD, JUMP_FUNCTION);
break;
}
case Token::SUB:
__ InvokeBuiltin(Builtins::SUB, JUMP_FUNCTION);
break;
case Token::MUL:
__ InvokeBuiltin(Builtins::MUL, JUMP_FUNCTION);
break;
case Token::DIV:
__ InvokeBuiltin(Builtins::DIV, JUMP_FUNCTION);
break;
case Token::MOD:
__ InvokeBuiltin(Builtins::MOD, JUMP_FUNCTION);
break;
case Token::BIT_OR:
__ InvokeBuiltin(Builtins::BIT_OR, JUMP_FUNCTION);
break;
case Token::BIT_AND:
__ InvokeBuiltin(Builtins::BIT_AND, JUMP_FUNCTION);
break;
case Token::BIT_XOR:
__ InvokeBuiltin(Builtins::BIT_XOR, JUMP_FUNCTION);
break;
case Token::SAR:
__ InvokeBuiltin(Builtins::SAR, JUMP_FUNCTION);
break;
case Token::SHL:
__ InvokeBuiltin(Builtins::SHL, JUMP_FUNCTION);
break;
case Token::SHR:
__ InvokeBuiltin(Builtins::SHR, JUMP_FUNCTION);
break;
default:
UNREACHABLE();
}
}
void GenericBinaryOpStub::GenerateLoadArguments(MacroAssembler* masm) {
// If arguments are not passed in registers read them from the stack.
if (!HasArgumentsInRegisters()) {
__ mov(eax, Operand(esp, 1 * kPointerSize));
__ mov(edx, Operand(esp, 2 * kPointerSize));
}
}
void GenericBinaryOpStub::GenerateReturn(MacroAssembler* masm) {
// If arguments are not passed in registers remove them from the stack before
// returning.
if (!HasArgumentsInRegisters()) {
__ ret(2 * kPointerSize); // Remove both operands
} else {
__ ret(0);
}
}
void FloatingPointHelper::LoadFloatOperand(MacroAssembler* masm,
Register number) {
Label load_smi, done;
__ test(number, Immediate(kSmiTagMask));
__ j(zero, &load_smi, not_taken);
__ fld_d(FieldOperand(number, HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&load_smi);
__ sar(number, kSmiTagSize);
__ push(number);
__ fild_s(Operand(esp, 0));
__ pop(number);
__ bind(&done);
}
void FloatingPointHelper::LoadSse2Operands(MacroAssembler* masm,
Label* not_numbers) {
Label load_smi_edx, load_eax, load_smi_eax, load_float_eax, done;
// Load operand in edx into xmm0, or branch to not_numbers.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &load_smi_edx, not_taken); // Argument in edx is a smi.
__ cmp(FieldOperand(edx, HeapObject::kMapOffset), Factory::heap_number_map());
__ j(not_equal, not_numbers); // Argument in edx is not a number.
__ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
__ bind(&load_eax);
// Load operand in eax into xmm1, or branch to not_numbers.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &load_smi_eax, not_taken); // Argument in eax is a smi.
__ cmp(FieldOperand(eax, HeapObject::kMapOffset), Factory::heap_number_map());
__ j(equal, &load_float_eax);
__ jmp(not_numbers); // Argument in eax is not a number.
__ bind(&load_smi_edx);
__ sar(edx, 1); // Untag smi before converting to float.
__ cvtsi2sd(xmm0, Operand(edx));
__ shl(edx, 1); // Retag smi for heap number overwriting test.
__ jmp(&load_eax);
__ bind(&load_smi_eax);
__ sar(eax, 1); // Untag smi before converting to float.
__ cvtsi2sd(xmm1, Operand(eax));
__ shl(eax, 1); // Retag smi for heap number overwriting test.
__ jmp(&done);
__ bind(&load_float_eax);
__ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
__ bind(&done);
}
void FloatingPointHelper::LoadFloatOperands(MacroAssembler* masm,
Register scratch) {
Label load_smi_1, load_smi_2, done_load_1, done;
__ mov(scratch, Operand(esp, 2 * kPointerSize));
__ test(scratch, Immediate(kSmiTagMask));
__ j(zero, &load_smi_1, not_taken);
__ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
__ bind(&done_load_1);
__ mov(scratch, Operand(esp, 1 * kPointerSize));
__ test(scratch, Immediate(kSmiTagMask));
__ j(zero, &load_smi_2, not_taken);
__ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&load_smi_1);
__ sar(scratch, kSmiTagSize);
__ push(scratch);
__ fild_s(Operand(esp, 0));
__ pop(scratch);
__ jmp(&done_load_1);
__ bind(&load_smi_2);
__ sar(scratch, kSmiTagSize);
__ push(scratch);
__ fild_s(Operand(esp, 0));
__ pop(scratch);
__ bind(&done);
}
void FloatingPointHelper::CheckFloatOperands(MacroAssembler* masm,
Label* non_float,
Register scratch) {
Label test_other, done;
// Test if both operands are floats or smi -> scratch=k_is_float;
// Otherwise scratch = k_not_float.
__ test(edx, Immediate(kSmiTagMask));
__ j(zero, &test_other, not_taken); // argument in edx is OK
__ mov(scratch, FieldOperand(edx, HeapObject::kMapOffset));
__ cmp(scratch, Factory::heap_number_map());
__ j(not_equal, non_float); // argument in edx is not a number -> NaN
__ bind(&test_other);
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &done); // argument in eax is OK
__ mov(scratch, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(scratch, Factory::heap_number_map());
__ j(not_equal, non_float); // argument in eax is not a number -> NaN
// Fall-through: Both operands are numbers.
__ bind(&done);
}
void UnarySubStub::Generate(MacroAssembler* masm) {
Label undo;
Label slow;
Label done;
Label try_float;
// Check whether the value is a smi.
__ test(eax, Immediate(kSmiTagMask));
__ j(not_zero, &try_float, not_taken);
// Enter runtime system if the value of the expression is zero
// to make sure that we switch between 0 and -0.
__ test(eax, Operand(eax));
__ j(zero, &slow, not_taken);
// The value of the expression is a smi that is not zero. Try
// optimistic subtraction '0 - value'.
__ mov(edx, Operand(eax));
__ Set(eax, Immediate(0));
__ sub(eax, Operand(edx));
__ j(overflow, &undo, not_taken);
// If result is a smi we are done.
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &done, taken);
// Restore eax and enter runtime system.
__ bind(&undo);
__ mov(eax, Operand(edx));
// Enter runtime system.
__ bind(&slow);
__ pop(ecx); // pop return address
__ push(eax);
__ push(ecx); // push return address
__ InvokeBuiltin(Builtins::UNARY_MINUS, JUMP_FUNCTION);
// Try floating point case.
__ bind(&try_float);
__ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
__ cmp(edx, Factory::heap_number_map());
__ j(not_equal, &slow);
if (overwrite_) {
__ mov(edx, FieldOperand(eax, HeapNumber::kExponentOffset));
__ xor_(edx, HeapNumber::kSignMask); // Flip sign.
__ mov(FieldOperand(eax, HeapNumber::kExponentOffset), edx);
} else {
__ mov(edx, Operand(eax));
// edx: operand
__ AllocateHeapNumber(eax, ebx, ecx, &undo);
// eax: allocated 'empty' number
__ mov(ecx, FieldOperand(edx, HeapNumber::kExponentOffset));
__ xor_(ecx, HeapNumber::kSignMask); // Flip sign.
__ mov(FieldOperand(eax, HeapNumber::kExponentOffset), ecx);
__ mov(ecx, FieldOperand(edx, HeapNumber::kMantissaOffset));
__ mov(FieldOperand(eax, HeapNumber::kMantissaOffset), ecx);
}
__ bind(&done);
__ StubReturn(1);
}
void ArgumentsAccessStub::GenerateReadLength(MacroAssembler* masm) {
// Check if the calling frame is an arguments adaptor frame.
Label adaptor;
__ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(equal, &adaptor);
// Nothing to do: The formal number of parameters has already been
// passed in register eax by calling function. Just return it.
__ ret(0);
// Arguments adaptor case: Read the arguments length from the
// adaptor frame and return it.
__ bind(&adaptor);
__ mov(eax, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ ret(0);
}
void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
// The key is in edx and the parameter count is in eax.
// The displacement is used for skipping the frame pointer on the
// stack. It is the offset of the last parameter (if any) relative
// to the frame pointer.
static const int kDisplacement = 1 * kPointerSize;
// Check that the key is a smi.
Label slow;
__ test(edx, Immediate(kSmiTagMask));
__ j(not_zero, &slow, not_taken);
// Check if the calling frame is an arguments adaptor frame.
Label adaptor;
__ mov(ebx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(ebx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(equal, &adaptor);
// Check index against formal parameters count limit passed in
// through register eax. Use unsigned comparison to get negative
// check for free.
__ cmp(edx, Operand(eax));
__ j(above_equal, &slow, not_taken);
// Read the argument from the stack and return it.
ASSERT(kSmiTagSize == 1 && kSmiTag == 0); // shifting code depends on this
__ lea(ebx, Operand(ebp, eax, times_2, 0));
__ neg(edx);
__ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
__ ret(0);
// Arguments adaptor case: Check index against actual arguments
// limit found in the arguments adaptor frame. Use unsigned
// comparison to get negative check for free.
__ bind(&adaptor);
__ mov(ecx, Operand(ebx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ cmp(edx, Operand(ecx));
__ j(above_equal, &slow, not_taken);
// Read the argument from the stack and return it.
ASSERT(kSmiTagSize == 1 && kSmiTag == 0); // shifting code depends on this
__ lea(ebx, Operand(ebx, ecx, times_2, 0));
__ neg(edx);
__ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
__ ret(0);
// Slow-case: Handle non-smi or out-of-bounds access to arguments
// by calling the runtime system.
__ bind(&slow);
__ pop(ebx); // Return address.
__ push(edx);
__ push(ebx);
__ TailCallRuntime(ExternalReference(Runtime::kGetArgumentsProperty), 1, 1);
}
void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* masm) {
// The displacement is used for skipping the return address and the
// frame pointer on the stack. It is the offset of the last
// parameter (if any) relative to the frame pointer.
static const int kDisplacement = 2 * kPointerSize;
// Check if the calling frame is an arguments adaptor frame.
Label runtime;
__ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
__ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
__ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ j(not_equal, &runtime);
// Patch the arguments.length and the parameters pointer.
__ mov(ecx, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ mov(Operand(esp, 1 * kPointerSize), ecx);
__ lea(edx, Operand(edx, ecx, times_2, kDisplacement));
__ mov(Operand(esp, 2 * kPointerSize), edx);
// Do the runtime call to allocate the arguments object.
__ bind(&runtime);
__ TailCallRuntime(ExternalReference(Runtime::kNewArgumentsFast), 3, 1);
}
void CompareStub::Generate(MacroAssembler* masm) {
Label call_builtin, done;
// NOTICE! This code is only reached after a smi-fast-case check, so
// it is certain that at least one operand isn't a smi.
if (cc_ == equal) { // Both strict and non-strict.
Label slow; // Fallthrough label.
// Equality is almost reflexive (everything but NaN), so start by testing
// for "identity and not NaN".
{
Label not_identical;
__ cmp(eax, Operand(edx));
__ j(not_equal, ¬_identical);
// Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
// so we do the second best thing - test it ourselves.
Label return_equal;
Label heap_number;
// If it's not a heap number, then return equal.
__ cmp(FieldOperand(edx, HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
__ j(equal, &heap_number);
__ bind(&return_equal);
__ Set(eax, Immediate(0));
__ ret(0);
__ bind(&heap_number);
// It is a heap number, so return non-equal if it's NaN and equal if it's
// not NaN.
// The representation of NaN values has all exponent bits (52..62) set,
// and not all mantissa bits (0..51) clear.
// We only accept QNaNs, which have bit 51 set.
// Read top bits of double representation (second word of value).
// Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
// all bits in the mask are set. We only need to check the word
// that contains the exponent and high bit of the mantissa.
ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
__ mov(edx, FieldOperand(edx, HeapNumber::kExponentOffset));
__ xor_(eax, Operand(eax));
// Shift value and mask so kQuietNaNHighBitsMask applies to topmost bits.
__ add(edx, Operand(edx));
__ cmp(edx, kQuietNaNHighBitsMask << 1);
__ setcc(above_equal, eax);
__ ret(0);
__ bind(¬_identical);
}
// If we're doing a strict equality comparison, we don't have to do
// type conversion, so we generate code to do fast comparison for objects
// and oddballs. Non-smi numbers and strings still go through the usual
// slow-case code.
if (strict_) {
// If either is a Smi (we know that not both are), then they can only
// be equal if the other is a HeapNumber. If so, use the slow case.
{
Label not_smis;
ASSERT_EQ(0, kSmiTag);
ASSERT_EQ(0, Smi::FromInt(0));
__ mov(ecx, Immediate(kSmiTagMask));
__ and_(ecx, Operand(eax));
__ test(ecx, Operand(edx));
__ j(not_zero, ¬_smis);
// One operand is a smi.
// Check whether the non-smi is a heap number.
ASSERT_EQ(1, kSmiTagMask);
// ecx still holds eax & kSmiTag, which is either zero or one.
__ sub(Operand(ecx), Immediate(0x01));
__ mov(ebx, edx);
__ xor_(ebx, Operand(eax));
__ and_(ebx, Operand(ecx)); // ebx holds either 0 or eax ^ edx.
__ xor_(ebx, Operand(eax));
// if eax was smi, ebx is now edx, else eax.
// Check if the non-smi operand is a heap number.
__ cmp(FieldOperand(ebx, HeapObject::kMapOffset),
Immediate(Factory::heap_number_map()));
// If heap number, handle it in the slow case.
__ j(equal, &slow);
// Return non-equal (ebx is not zero)
__ mov(eax, ebx);
__ ret(0);
__ bind(¬_smis);
}
// If either operand is a JSObject or an oddball value, then they are not
// equal since their pointers are different
// There is no test for undetectability in strict equality.
// Get the type of the first operand.
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
// If the first object is a JS object, we have done pointer comparison.
ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
Label first_non_object;
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &first_non_object);
// Return non-zero (eax is not zero)
Label return_not_equal;
ASSERT(kHeapObjectTag != 0);
__ bind(&return_not_equal);
__ ret(0);
__ bind(&first_non_object);
// Check for oddballs: true, false, null, undefined.
__ cmp(ecx, ODDBALL_TYPE);
__ j(equal, &return_not_equal);
__ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(greater_equal, &return_not_equal);
// Check for oddballs: true, false, null, undefined.
__ cmp(ecx, ODDBALL_TYPE);
__ j(equal, &return_not_equal);
// Fall through to the general case.
}
__ bind(&slow);
}
// Push arguments below the return address.
__ pop(ecx);
__ push(eax);
__ push(edx);
__ push(ecx);
// Inlined floating point compare.
// Call builtin if operands are not floating point or smi.
Label check_for_symbols;
Label unordered;
if (CpuFeatures::IsSupported(CpuFeatures::SSE2)) {
CpuFeatures::Scope use_sse2(CpuFeatures::SSE2);
CpuFeatures::Scope use_cmov(CpuFeatures::CMOV);
FloatingPointHelper::LoadSse2Operands(masm, &check_for_symbols);
__ comisd(xmm0, xmm1);
// Jump to builtin for NaN.
__ j(parity_even, &unordered, not_taken);
__ mov(eax, 0); // equal
__ mov(ecx, Immediate(Smi::FromInt(1)));
__ cmov(above, eax, Operand(ecx));
__ mov(ecx, Immediate(Smi::FromInt(-1)));
__ cmov(below, eax, Operand(ecx));
__ ret(2 * kPointerSize);
} else {
FloatingPointHelper::CheckFloatOperands(masm, &check_for_symbols, ebx);
FloatingPointHelper::LoadFloatOperands(masm, ecx);
__ FCmp();
// Jump to builtin for NaN.
__ j(parity_even, &unordered, not_taken);
Label below_lbl, above_lbl;
// Return a result of -1, 0, or 1, to indicate result of comparison.
__ j(below, &below_lbl, not_taken);
__ j(above, &above_lbl, not_taken);
__ xor_(eax, Operand(eax)); // equal
// Both arguments were pushed in case a runtime call was needed.
__ ret(2 * kPointerSize);
__ bind(&below_lbl);
__ mov(eax, Immediate(Smi::FromInt(-1)));
__ ret(2 * kPointerSize);
__ bind(&above_lbl);
__ mov(eax, Immediate(Smi::FromInt(1)));
__ ret(2 * kPointerSize); // eax, edx were pushed
}
// If one of the numbers was NaN, then the result is always false.
// The cc is never not-equal.
__ bind(&unordered);
ASSERT(cc_ != not_equal);
if (cc_ == less || cc_ == less_equal) {
__ mov(eax, Immediate(Smi::FromInt(1)));
} else {
__ mov(eax, Immediate(Smi::FromInt(-1)));
}
__ ret(2 * kPointerSize); // eax, edx were pushed
// Fast negative check for symbol-to-symbol equality.
__ bind(&check_for_symbols);
if (cc_ == equal) {
BranchIfNonSymbol(masm, &call_builtin, eax, ecx);
BranchIfNonSymbol(masm, &call_builtin, edx, ecx);
// We've already checked for object identity, so if both operands
// are symbols they aren't equal. Register eax already holds a
// non-zero value, which indicates not equal, so just return.
__ ret(2 * kPointerSize);
}
__ bind(&call_builtin);
// must swap argument order
__ pop(ecx);
__ pop(edx);
__ pop(eax);
__ push(edx);
__ push(eax);
// Figure out which native to call and setup the arguments.
Builtins::JavaScript builtin;
if (cc_ == equal) {
builtin = strict_ ? Builtins::STRICT_EQUALS : Builtins::EQUALS;
} else {
builtin = Builtins::COMPARE;
int ncr; // NaN compare result
if (cc_ == less || cc_ == less_equal) {
ncr = GREATER;
} else {
ASSERT(cc_ == greater || cc_ == greater_equal); // remaining cases
ncr = LESS;
}
__ push(Immediate(Smi::FromInt(ncr)));
}
// Restore return address on the stack.
__ push(ecx);
// Call the native; it returns -1 (less), 0 (equal), or 1 (greater)
// tagged as a small integer.
__ InvokeBuiltin(builtin, JUMP_FUNCTION);
}
void CompareStub::BranchIfNonSymbol(MacroAssembler* masm,
Label* label,
Register object,
Register scratch) {
__ test(object, Immediate(kSmiTagMask));
__ j(zero, label);
__ mov(scratch, FieldOperand(object, HeapObject::kMapOffset));
__ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
__ and_(scratch, kIsSymbolMask | kIsNotStringMask);
__ cmp(scratch, kSymbolTag | kStringTag);
__ j(not_equal, label);
}
void StackCheckStub::Generate(MacroAssembler* masm) {
// Because builtins always remove the receiver from the stack, we
// have to fake one to avoid underflowing the stack. The receiver
// must be inserted below the return address on the stack so we
// temporarily store that in a register.
__ pop(eax);
__ push(Immediate(Smi::FromInt(0)));
__ push(eax);
// Do tail-call to runtime routine.
__ TailCallRuntime(ExternalReference(Runtime::kStackGuard), 1, 1);
}
void CallFunctionStub::Generate(MacroAssembler* masm) {
Label slow;
// Get the function to call from the stack.
// +2 ~ receiver, return address
__ mov(edi, Operand(esp, (argc_ + 2) * kPointerSize));
// Check that the function really is a JavaScript function.
__ test(edi, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
// Goto slow case if we do not have a function.
__ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
__ j(not_equal, &slow, not_taken);
// Fast-case: Just invoke the function.
ParameterCount actual(argc_);
__ InvokeFunction(edi, actual, JUMP_FUNCTION);
// Slow-case: Non-function called.
__ bind(&slow);
__ Set(eax, Immediate(argc_));
__ Set(ebx, Immediate(0));
__ GetBuiltinEntry(edx, Builtins::CALL_NON_FUNCTION);
Handle<Code> adaptor(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline));
__ jmp(adaptor, RelocInfo::CODE_TARGET);
}
int CEntryStub::MinorKey() {
ASSERT(result_size_ <= 2);
// Result returned in eax, or eax+edx if result_size_ is 2.
return 0;
}
void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
// eax holds the exception.
// Adjust this code if not the case.
ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop the sp to the top of the handler.
ExternalReference handler_address(Top::k_handler_address);
__ mov(esp, Operand::StaticVariable(handler_address));
// Restore next handler and frame pointer, discard handler state.
ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(Operand::StaticVariable(handler_address));
ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
__ pop(ebp);
__ pop(edx); // Remove state.
// Before returning we restore the context from the frame pointer if
// not NULL. The frame pointer is NULL in the exception handler of
// a JS entry frame.
__ xor_(esi, Operand(esi)); // Tentatively set context pointer to NULL.
Label skip;
__ cmp(ebp, 0);
__ j(equal, &skip, not_taken);
__ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
__ bind(&skip);
ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ ret(0);
}
void CEntryStub::GenerateCore(MacroAssembler* masm,
Label* throw_normal_exception,
Label* throw_termination_exception,
Label* throw_out_of_memory_exception,
StackFrame::Type frame_type,
bool do_gc,
bool always_allocate_scope) {
// eax: result parameter for PerformGC, if any
// ebx: pointer to C function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// edi: number of arguments including receiver (C callee-saved)
// esi: pointer to the first argument (C callee-saved)
if (do_gc) {
__ mov(Operand(esp, 0 * kPointerSize), eax); // Result.
__ call(FUNCTION_ADDR(Runtime::PerformGC), RelocInfo::RUNTIME_ENTRY);
}
ExternalReference scope_depth =
ExternalReference::heap_always_allocate_scope_depth();
if (always_allocate_scope) {
__ inc(Operand::StaticVariable(scope_depth));
}
// Call C function.
__ mov(Operand(esp, 0 * kPointerSize), edi); // argc.
__ mov(Operand(esp, 1 * kPointerSize), esi); // argv.
__ call(Operand(ebx));
// Result is in eax or edx:eax - do not destroy these registers!
if (always_allocate_scope) {
__ dec(Operand::StaticVariable(scope_depth));
}
// Make sure we're not trying to return 'the hole' from the runtime
// call as this may lead to crashes in the IC code later.
if (FLAG_debug_code) {
Label okay;
__ cmp(eax, Factory::the_hole_value());
__ j(not_equal, &okay);
__ int3();
__ bind(&okay);
}
// Check for failure result.
Label failure_returned;
ASSERT(((kFailureTag + 1) & kFailureTagMask) == 0);
__ lea(ecx, Operand(eax, 1));
// Lower 2 bits of ecx are 0 iff eax has failure tag.
__ test(ecx, Immediate(kFailureTagMask));
__ j(zero, &failure_returned, not_taken);
// Exit the JavaScript to C++ exit frame.
__ LeaveExitFrame(frame_type);
__ ret(0);
// Handling of failure.
__ bind(&failure_returned);
Label retry;
// If the returned exception is RETRY_AFTER_GC continue at retry label
ASSERT(Failure::RETRY_AFTER_GC == 0);
__ test(eax, Immediate(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize));
__ j(zero, &retry, taken);
// Special handling of out of memory exceptions.
__ cmp(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
__ j(equal, throw_out_of_memory_exception);
// Retrieve the pending exception and clear the variable.
ExternalReference pending_exception_address(Top::k_pending_exception_address);
__ mov(eax, Operand::StaticVariable(pending_exception_address));
__ mov(edx,
Operand::StaticVariable(ExternalReference::the_hole_value_location()));
__ mov(Operand::StaticVariable(pending_exception_address), edx);
// Special handling of termination exceptions which are uncatchable
// by javascript code.
__ cmp(eax, Factory::termination_exception());
__ j(equal, throw_termination_exception);
// Handle normal exception.
__ jmp(throw_normal_exception);
// Retry.
__ bind(&retry);
}
void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm,
UncatchableExceptionType type) {
// Adjust this code if not the case.
ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop sp to the top stack handler.
ExternalReference handler_address(Top::k_handler_address);
__ mov(esp, Operand::StaticVariable(handler_address));
// Unwind the handlers until the ENTRY handler is found.
Label loop, done;
__ bind(&loop);
// Load the type of the current stack handler.
const int kStateOffset = StackHandlerConstants::kStateOffset;
__ cmp(Operand(esp, kStateOffset), Immediate(StackHandler::ENTRY));
__ j(equal, &done);
// Fetch the next handler in the list.
const int kNextOffset = StackHandlerConstants::kNextOffset;
__ mov(esp, Operand(esp, kNextOffset));
__ jmp(&loop);
__ bind(&done);
// Set the top handler address to next handler past the current ENTRY handler.
ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(Operand::StaticVariable(handler_address));
if (type == OUT_OF_MEMORY) {
// Set external caught exception to false.
ExternalReference external_caught(Top::k_external_caught_exception_address);
__ mov(eax, false);
__ mov(Operand::StaticVariable(external_caught), eax);
// Set pending exception and eax to out of memory exception.
ExternalReference pending_exception(Top::k_pending_exception_address);
__ mov(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
__ mov(Operand::StaticVariable(pending_exception), eax);
}
// Clear the context pointer.
__ xor_(esi, Operand(esi));
// Restore fp from handler and discard handler state.
ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
__ pop(ebp);
__ pop(edx); // State.
ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ ret(0);
}
void CEntryStub::GenerateBody(MacroAssembler* masm, bool is_debug_break) {
// eax: number of arguments including receiver
// ebx: pointer to C function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// esi: current context (C callee-saved)
// edi: JS function of the caller (C callee-saved)
// NOTE: Invocations of builtins may return failure objects instead
// of a proper result. The builtin entry handles this by performing
// a garbage collection and retrying the builtin (twice).
StackFrame::Type frame_type = is_debug_break ?
StackFrame::EXIT_DEBUG :
StackFrame::EXIT;
// Enter the exit frame that transitions from JavaScript to C++.
__ EnterExitFrame(frame_type);
// eax: result parameter for PerformGC, if any (setup below)
// ebx: pointer to builtin function (C callee-saved)
// ebp: frame pointer (restored after C call)
// esp: stack pointer (restored after C call)
// edi: number of arguments including receiver (C callee-saved)
// esi: argv pointer (C callee-saved)
Label throw_normal_exception;
Label throw_termination_exception;
Label throw_out_of_memory_exception;
// Call into the runtime system.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
frame_type,
false,
false);
// Do space-specific GC and retry runtime call.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
frame_type,
true,
false);
// Do full GC and retry runtime call one final time.
Failure* failure = Failure::InternalError();
__ mov(eax, Immediate(reinterpret_cast<int32_t>(failure)));
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
frame_type,
true,
true);
__ bind(&throw_out_of_memory_exception);
GenerateThrowUncatchable(masm, OUT_OF_MEMORY);
__ bind(&throw_termination_exception);
GenerateThrowUncatchable(masm, TERMINATION);
__ bind(&throw_normal_exception);
GenerateThrowTOS(masm);
}
void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
Label invoke, exit;
#ifdef ENABLE_LOGGING_AND_PROFILING
Label not_outermost_js, not_outermost_js_2;
#endif
// Setup frame.
__ push(ebp);
__ mov(ebp, Operand(esp));
// Push marker in two places.
int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
__ push(Immediate(Smi::FromInt(marker))); // context slot
__ push(Immediate(Smi::FromInt(marker))); // function slot
// Save callee-saved registers (C calling conventions).
__ push(edi);
__ push(esi);
__ push(ebx);
// Save copies of the top frame descriptor on the stack.
ExternalReference c_entry_fp(Top::k_c_entry_fp_address);
__ push(Operand::StaticVariable(c_entry_fp));
#ifdef ENABLE_LOGGING_AND_PROFILING
// If this is the outermost JS call, set js_entry_sp value.
ExternalReference js_entry_sp(Top::k_js_entry_sp_address);
__ cmp(Operand::StaticVariable(js_entry_sp), Immediate(0));
__ j(not_equal, ¬_outermost_js);
__ mov(Operand::StaticVariable(js_entry_sp), ebp);
__ bind(¬_outermost_js);
#endif
// Call a faked try-block that does the invoke.
__ call(&invoke);
// Caught exception: Store result (exception) in the pending
// exception field in the JSEnv and return a failure sentinel.
ExternalReference pending_exception(Top::k_pending_exception_address);
__ mov(Operand::StaticVariable(pending_exception), eax);
__ mov(eax, reinterpret_cast<int32_t>(Failure::Exception()));
__ jmp(&exit);
// Invoke: Link this frame into the handler chain.
__ bind(&invoke);
__ PushTryHandler(IN_JS_ENTRY, JS_ENTRY_HANDLER);
// Clear any pending exceptions.
__ mov(edx,
Operand::StaticVariable(ExternalReference::the_hole_value_location()));
__ mov(Operand::StaticVariable(pending_exception), edx);
// Fake a receiver (NULL).
__ push(Immediate(0)); // receiver
// Invoke the function by calling through JS entry trampoline
// builtin and pop the faked function when we return. Notice that we
// cannot store a reference to the trampoline code directly in this
// stub, because the builtin stubs may not have been generated yet.
if (is_construct) {
ExternalReference construct_entry(Builtins::JSConstructEntryTrampoline);
__ mov(edx, Immediate(construct_entry));
} else {
ExternalReference entry(Builtins::JSEntryTrampoline);
__ mov(edx, Immediate(entry));
}
__ mov(edx, Operand(edx, 0)); // deref address
__ lea(edx, FieldOperand(edx, Code::kHeaderSize));
__ call(Operand(edx));
// Unlink this frame from the handler chain.
__ pop(Operand::StaticVariable(ExternalReference(Top::k_handler_address)));
// Pop next_sp.
__ add(Operand(esp), Immediate(StackHandlerConstants::kSize - kPointerSize));
#ifdef ENABLE_LOGGING_AND_PROFILING
// If current EBP value is the same as js_entry_sp value, it means that
// the current function is the outermost.
__ cmp(ebp, Operand::StaticVariable(js_entry_sp));
__ j(not_equal, ¬_outermost_js_2);
__ mov(Operand::StaticVariable(js_entry_sp), Immediate(0));
__ bind(¬_outermost_js_2);
#endif
// Restore the top frame descriptor from the stack.
__ bind(&exit);
__ pop(Operand::StaticVariable(ExternalReference(Top::k_c_entry_fp_address)));
// Restore callee-saved registers (C calling conventions).
__ pop(ebx);
__ pop(esi);
__ pop(edi);
__ add(Operand(esp), Immediate(2 * kPointerSize)); // remove markers
// Restore frame pointer and return.
__ pop(ebp);
__ ret(0);
}
void InstanceofStub::Generate(MacroAssembler* masm) {
// Get the object - go slow case if it's a smi.
Label slow;
__ mov(eax, Operand(esp, 2 * kPointerSize)); // 2 ~ return address, function
__ test(eax, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
// Check that the left hand is a JS object.
__ mov(eax, FieldOperand(eax, HeapObject::kMapOffset)); // eax - object map
__ movzx_b(ecx, FieldOperand(eax, Map::kInstanceTypeOffset)); // ecx - type
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &slow, not_taken);
__ cmp(ecx, LAST_JS_OBJECT_TYPE);
__ j(greater, &slow, not_taken);
// Get the prototype of the function.
__ mov(edx, Operand(esp, 1 * kPointerSize)); // 1 ~ return address
__ TryGetFunctionPrototype(edx, ebx, ecx, &slow);
// Check that the function prototype is a JS object.
__ test(ebx, Immediate(kSmiTagMask));
__ j(zero, &slow, not_taken);
__ mov(ecx, FieldOperand(ebx, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
__ cmp(ecx, FIRST_JS_OBJECT_TYPE);
__ j(less, &slow, not_taken);
__ cmp(ecx, LAST_JS_OBJECT_TYPE);
__ j(greater, &slow, not_taken);
// Register mapping: eax is object map and ebx is function prototype.
__ mov(ecx, FieldOperand(eax, Map::kPrototypeOffset));
// Loop through the prototype chain looking for the function prototype.
Label loop, is_instance, is_not_instance;
__ bind(&loop);
__ cmp(ecx, Operand(ebx));
__ j(equal, &is_instance);
__ cmp(Operand(ecx), Immediate(Factory::null_value()));
__ j(equal, &is_not_instance);
__ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
__ mov(ecx, FieldOperand(ecx, Map::kPrototypeOffset));
__ jmp(&loop);
__ bind(&is_instance);
__ Set(eax, Immediate(0));
__ ret(2 * kPointerSize);
__ bind(&is_not_instance);
__ Set(eax, Immediate(Smi::FromInt(1)));
__ ret(2 * kPointerSize);
// Slow-case: Go through the JavaScript implementation.
__ bind(&slow);
__ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
}
int CompareStub::MinorKey() {
// Encode the two parameters in a unique 16 bit value.
ASSERT(static_cast<unsigned>(cc_) < (1 << 15));
return (static_cast<unsigned>(cc_) << 1) | (strict_ ? 1 : 0);
}
#undef __
} } // namespace v8::internal