blob: b4f4a0611afb82a44dda19353333573e94993a18 [file] [log] [blame]
// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "v8.h"
#include "api.h"
#include "arguments.h"
#include "bootstrapper.h"
#include "builtins.h"
#include "ic-inl.h"
namespace v8 {
namespace internal {
namespace {
// Arguments object passed to C++ builtins.
template <BuiltinExtraArguments extra_args>
class BuiltinArguments : public Arguments {
public:
BuiltinArguments(int length, Object** arguments)
: Arguments(length, arguments) { }
Object*& operator[] (int index) {
ASSERT(index < length());
return Arguments::operator[](index);
}
template <class S> Handle<S> at(int index) {
ASSERT(index < length());
return Arguments::at<S>(index);
}
Handle<Object> receiver() {
return Arguments::at<Object>(0);
}
Handle<JSFunction> called_function() {
STATIC_ASSERT(extra_args == NEEDS_CALLED_FUNCTION);
return Arguments::at<JSFunction>(Arguments::length() - 1);
}
// Gets the total number of arguments including the receiver (but
// excluding extra arguments).
int length() const {
STATIC_ASSERT(extra_args == NO_EXTRA_ARGUMENTS);
return Arguments::length();
}
#ifdef DEBUG
void Verify() {
// Check we have at least the receiver.
ASSERT(Arguments::length() >= 1);
}
#endif
};
// Specialize BuiltinArguments for the called function extra argument.
template <>
int BuiltinArguments<NEEDS_CALLED_FUNCTION>::length() const {
return Arguments::length() - 1;
}
#ifdef DEBUG
template <>
void BuiltinArguments<NEEDS_CALLED_FUNCTION>::Verify() {
// Check we have at least the receiver and the called function.
ASSERT(Arguments::length() >= 2);
// Make sure cast to JSFunction succeeds.
called_function();
}
#endif
#define DEF_ARG_TYPE(name, spec) \
typedef BuiltinArguments<spec> name##ArgumentsType;
BUILTIN_LIST_C(DEF_ARG_TYPE)
#undef DEF_ARG_TYPE
} // namespace
// ----------------------------------------------------------------------------
// Support macro for defining builtins in C++.
// ----------------------------------------------------------------------------
//
// A builtin function is defined by writing:
//
// BUILTIN(name) {
// ...
// }
//
// In the body of the builtin function the arguments can be accessed
// through the BuiltinArguments object args.
#ifdef DEBUG
#define BUILTIN(name) \
static Object* Builtin_Impl_##name(name##ArgumentsType args); \
static Object* Builtin_##name(name##ArgumentsType args) { \
args.Verify(); \
return Builtin_Impl_##name(args); \
} \
static Object* Builtin_Impl_##name(name##ArgumentsType args)
#else // For release mode.
#define BUILTIN(name) \
static Object* Builtin_##name(name##ArgumentsType args)
#endif
static inline bool CalledAsConstructor() {
#ifdef DEBUG
// Calculate the result using a full stack frame iterator and check
// that the state of the stack is as we assume it to be in the
// code below.
StackFrameIterator it;
ASSERT(it.frame()->is_exit());
it.Advance();
StackFrame* frame = it.frame();
bool reference_result = frame->is_construct();
#endif
Address fp = Top::c_entry_fp(Top::GetCurrentThread());
// Because we know fp points to an exit frame we can use the relevant
// part of ExitFrame::ComputeCallerState directly.
const int kCallerOffset = ExitFrameConstants::kCallerFPOffset;
Address caller_fp = Memory::Address_at(fp + kCallerOffset);
// This inlines the part of StackFrame::ComputeType that grabs the
// type of the current frame. Note that StackFrame::ComputeType
// has been specialized for each architecture so if any one of them
// changes this code has to be changed as well.
const int kMarkerOffset = StandardFrameConstants::kMarkerOffset;
const Smi* kConstructMarker = Smi::FromInt(StackFrame::CONSTRUCT);
Object* marker = Memory::Object_at(caller_fp + kMarkerOffset);
bool result = (marker == kConstructMarker);
ASSERT_EQ(result, reference_result);
return result;
}
// ----------------------------------------------------------------------------
BUILTIN(Illegal) {
UNREACHABLE();
return Heap::undefined_value(); // Make compiler happy.
}
BUILTIN(EmptyFunction) {
return Heap::undefined_value();
}
BUILTIN(ArrayCodeGeneric) {
Counters::array_function_runtime.Increment();
JSArray* array;
if (CalledAsConstructor()) {
array = JSArray::cast(*args.receiver());
} else {
// Allocate the JS Array
JSFunction* constructor =
Top::context()->global_context()->array_function();
Object* obj = Heap::AllocateJSObject(constructor);
if (obj->IsFailure()) return obj;
array = JSArray::cast(obj);
}
// 'array' now contains the JSArray we should initialize.
ASSERT(array->HasFastElements());
// Optimize the case where there is one argument and the argument is a
// small smi.
if (args.length() == 2) {
Object* obj = args[1];
if (obj->IsSmi()) {
int len = Smi::cast(obj)->value();
if (len >= 0 && len < JSObject::kInitialMaxFastElementArray) {
Object* obj = Heap::AllocateFixedArrayWithHoles(len);
if (obj->IsFailure()) return obj;
array->SetContent(FixedArray::cast(obj));
return array;
}
}
// Take the argument as the length.
obj = array->Initialize(0);
if (obj->IsFailure()) return obj;
return array->SetElementsLength(args[1]);
}
// Optimize the case where there are no parameters passed.
if (args.length() == 1) {
return array->Initialize(JSArray::kPreallocatedArrayElements);
}
// Take the arguments as elements.
int number_of_elements = args.length() - 1;
Smi* len = Smi::FromInt(number_of_elements);
Object* obj = Heap::AllocateFixedArrayWithHoles(len->value());
if (obj->IsFailure()) return obj;
AssertNoAllocation no_gc;
FixedArray* elms = FixedArray::cast(obj);
WriteBarrierMode mode = elms->GetWriteBarrierMode(no_gc);
// Fill in the content
for (int index = 0; index < number_of_elements; index++) {
elms->set(index, args[index+1], mode);
}
// Set length and elements on the array.
array->set_elements(FixedArray::cast(obj));
array->set_length(len);
return array;
}
MUST_USE_RESULT static Object* AllocateJSArray() {
JSFunction* array_function =
Top::context()->global_context()->array_function();
Object* result = Heap::AllocateJSObject(array_function);
if (result->IsFailure()) return result;
return result;
}
MUST_USE_RESULT static Object* AllocateEmptyJSArray() {
Object* result = AllocateJSArray();
if (result->IsFailure()) return result;
JSArray* result_array = JSArray::cast(result);
result_array->set_length(Smi::FromInt(0));
result_array->set_elements(Heap::empty_fixed_array());
return result_array;
}
static void CopyElements(AssertNoAllocation* no_gc,
FixedArray* dst,
int dst_index,
FixedArray* src,
int src_index,
int len) {
ASSERT(dst != src); // Use MoveElements instead.
ASSERT(dst->map() != Heap::fixed_cow_array_map());
ASSERT(len > 0);
CopyWords(dst->data_start() + dst_index,
src->data_start() + src_index,
len);
WriteBarrierMode mode = dst->GetWriteBarrierMode(*no_gc);
if (mode == UPDATE_WRITE_BARRIER) {
Heap::RecordWrites(dst->address(), dst->OffsetOfElementAt(dst_index), len);
}
}
static void MoveElements(AssertNoAllocation* no_gc,
FixedArray* dst,
int dst_index,
FixedArray* src,
int src_index,
int len) {
ASSERT(dst->map() != Heap::fixed_cow_array_map());
memmove(dst->data_start() + dst_index,
src->data_start() + src_index,
len * kPointerSize);
WriteBarrierMode mode = dst->GetWriteBarrierMode(*no_gc);
if (mode == UPDATE_WRITE_BARRIER) {
Heap::RecordWrites(dst->address(), dst->OffsetOfElementAt(dst_index), len);
}
}
static void FillWithHoles(FixedArray* dst, int from, int to) {
ASSERT(dst->map() != Heap::fixed_cow_array_map());
MemsetPointer(dst->data_start() + from, Heap::the_hole_value(), to - from);
}
static FixedArray* LeftTrimFixedArray(FixedArray* elms, int to_trim) {
ASSERT(elms->map() != Heap::fixed_cow_array_map());
// For now this trick is only applied to fixed arrays in new and paged space.
// In large object space the object's start must coincide with chunk
// and thus the trick is just not applicable.
ASSERT(!Heap::lo_space()->Contains(elms));
STATIC_ASSERT(FixedArray::kMapOffset == 0);
STATIC_ASSERT(FixedArray::kLengthOffset == kPointerSize);
STATIC_ASSERT(FixedArray::kHeaderSize == 2 * kPointerSize);
Object** former_start = HeapObject::RawField(elms, 0);
const int len = elms->length();
if (to_trim > FixedArray::kHeaderSize / kPointerSize &&
!Heap::new_space()->Contains(elms)) {
// If we are doing a big trim in old space then we zap the space that was
// formerly part of the array so that the GC (aided by the card-based
// remembered set) won't find pointers to new-space there.
Object** zap = reinterpret_cast<Object**>(elms->address());
zap++; // Header of filler must be at least one word so skip that.
for (int i = 1; i < to_trim; i++) {
*zap++ = Smi::FromInt(0);
}
}
// Technically in new space this write might be omitted (except for
// debug mode which iterates through the heap), but to play safer
// we still do it.
Heap::CreateFillerObjectAt(elms->address(), to_trim * kPointerSize);
former_start[to_trim] = Heap::fixed_array_map();
former_start[to_trim + 1] = Smi::FromInt(len - to_trim);
return FixedArray::cast(HeapObject::FromAddress(
elms->address() + to_trim * kPointerSize));
}
static bool ArrayPrototypeHasNoElements(Context* global_context,
JSObject* array_proto) {
// This method depends on non writability of Object and Array prototype
// fields.
if (array_proto->elements() != Heap::empty_fixed_array()) return false;
// Hidden prototype
array_proto = JSObject::cast(array_proto->GetPrototype());
ASSERT(array_proto->elements() == Heap::empty_fixed_array());
// Object.prototype
array_proto = JSObject::cast(array_proto->GetPrototype());
if (array_proto != global_context->initial_object_prototype()) return false;
if (array_proto->elements() != Heap::empty_fixed_array()) return false;
ASSERT(array_proto->GetPrototype()->IsNull());
return true;
}
static inline Object* EnsureJSArrayWithWritableFastElements(Object* receiver) {
if (!receiver->IsJSArray()) return NULL;
JSArray* array = JSArray::cast(receiver);
HeapObject* elms = HeapObject::cast(array->elements());
if (elms->map() == Heap::fixed_array_map()) return elms;
if (elms->map() == Heap::fixed_cow_array_map()) {
return array->EnsureWritableFastElements();
}
return NULL;
}
static inline bool IsJSArrayFastElementMovingAllowed(JSArray* receiver) {
Context* global_context = Top::context()->global_context();
JSObject* array_proto =
JSObject::cast(global_context->array_function()->prototype());
return receiver->GetPrototype() == array_proto &&
ArrayPrototypeHasNoElements(global_context, array_proto);
}
static Object* CallJsBuiltin(const char* name,
BuiltinArguments<NO_EXTRA_ARGUMENTS> args) {
HandleScope handleScope;
Handle<Object> js_builtin =
GetProperty(Handle<JSObject>(Top::global_context()->builtins()),
name);
ASSERT(js_builtin->IsJSFunction());
Handle<JSFunction> function(Handle<JSFunction>::cast(js_builtin));
ScopedVector<Object**> argv(args.length() - 1);
int n_args = args.length() - 1;
for (int i = 0; i < n_args; i++) {
argv[i] = args.at<Object>(i + 1).location();
}
bool pending_exception = false;
Handle<Object> result = Execution::Call(function,
args.receiver(),
n_args,
argv.start(),
&pending_exception);
if (pending_exception) return Failure::Exception();
return *result;
}
BUILTIN(ArrayPush) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj == NULL) return CallJsBuiltin("ArrayPush", args);
if (elms_obj->IsFailure()) return elms_obj;
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
int len = Smi::cast(array->length())->value();
int to_add = args.length() - 1;
if (to_add == 0) {
return Smi::FromInt(len);
}
// Currently fixed arrays cannot grow too big, so
// we should never hit this case.
ASSERT(to_add <= (Smi::kMaxValue - len));
int new_length = len + to_add;
if (new_length > elms->length()) {
// New backing storage is needed.
int capacity = new_length + (new_length >> 1) + 16;
Object* obj = Heap::AllocateUninitializedFixedArray(capacity);
if (obj->IsFailure()) return obj;
FixedArray* new_elms = FixedArray::cast(obj);
AssertNoAllocation no_gc;
if (len > 0) {
CopyElements(&no_gc, new_elms, 0, elms, 0, len);
}
FillWithHoles(new_elms, new_length, capacity);
elms = new_elms;
array->set_elements(elms);
}
// Add the provided values.
AssertNoAllocation no_gc;
WriteBarrierMode mode = elms->GetWriteBarrierMode(no_gc);
for (int index = 0; index < to_add; index++) {
elms->set(index + len, args[index + 1], mode);
}
// Set the length.
array->set_length(Smi::FromInt(new_length));
return Smi::FromInt(new_length);
}
BUILTIN(ArrayPop) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj == NULL) return CallJsBuiltin("ArrayPop", args);
if (elms_obj->IsFailure()) return elms_obj;
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
int len = Smi::cast(array->length())->value();
if (len == 0) return Heap::undefined_value();
// Get top element
Object* top = elms->get(len - 1);
// Set the length.
array->set_length(Smi::FromInt(len - 1));
if (!top->IsTheHole()) {
// Delete the top element.
elms->set_the_hole(len - 1);
return top;
}
top = array->GetPrototype()->GetElement(len - 1);
return top;
}
BUILTIN(ArrayShift) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj->IsFailure()) return elms_obj;
if (elms_obj == NULL ||
!IsJSArrayFastElementMovingAllowed(JSArray::cast(receiver))) {
return CallJsBuiltin("ArrayShift", args);
}
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
ASSERT(array->HasFastElements());
int len = Smi::cast(array->length())->value();
if (len == 0) return Heap::undefined_value();
// Get first element
Object* first = elms->get(0);
if (first->IsTheHole()) {
first = Heap::undefined_value();
}
if (!Heap::lo_space()->Contains(elms)) {
// As elms still in the same space they used to be,
// there is no need to update region dirty mark.
array->set_elements(LeftTrimFixedArray(elms, 1), SKIP_WRITE_BARRIER);
} else {
// Shift the elements.
AssertNoAllocation no_gc;
MoveElements(&no_gc, elms, 0, elms, 1, len - 1);
elms->set(len - 1, Heap::the_hole_value());
}
// Set the length.
array->set_length(Smi::FromInt(len - 1));
return first;
}
BUILTIN(ArrayUnshift) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj->IsFailure()) return elms_obj;
if (elms_obj == NULL ||
!IsJSArrayFastElementMovingAllowed(JSArray::cast(receiver))) {
return CallJsBuiltin("ArrayUnshift", args);
}
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
ASSERT(array->HasFastElements());
int len = Smi::cast(array->length())->value();
int to_add = args.length() - 1;
int new_length = len + to_add;
// Currently fixed arrays cannot grow too big, so
// we should never hit this case.
ASSERT(to_add <= (Smi::kMaxValue - len));
if (new_length > elms->length()) {
// New backing storage is needed.
int capacity = new_length + (new_length >> 1) + 16;
Object* obj = Heap::AllocateUninitializedFixedArray(capacity);
if (obj->IsFailure()) return obj;
FixedArray* new_elms = FixedArray::cast(obj);
AssertNoAllocation no_gc;
if (len > 0) {
CopyElements(&no_gc, new_elms, to_add, elms, 0, len);
}
FillWithHoles(new_elms, new_length, capacity);
elms = new_elms;
array->set_elements(elms);
} else {
AssertNoAllocation no_gc;
MoveElements(&no_gc, elms, to_add, elms, 0, len);
}
// Add the provided values.
AssertNoAllocation no_gc;
WriteBarrierMode mode = elms->GetWriteBarrierMode(no_gc);
for (int i = 0; i < to_add; i++) {
elms->set(i, args[i + 1], mode);
}
// Set the length.
array->set_length(Smi::FromInt(new_length));
return Smi::FromInt(new_length);
}
BUILTIN(ArraySlice) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj->IsFailure()) return elms_obj;
if (elms_obj == NULL ||
!IsJSArrayFastElementMovingAllowed(JSArray::cast(receiver))) {
return CallJsBuiltin("ArraySlice", args);
}
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
ASSERT(array->HasFastElements());
int len = Smi::cast(array->length())->value();
int n_arguments = args.length() - 1;
// Note carefully choosen defaults---if argument is missing,
// it's undefined which gets converted to 0 for relative_start
// and to len for relative_end.
int relative_start = 0;
int relative_end = len;
if (n_arguments > 0) {
Object* arg1 = args[1];
if (arg1->IsSmi()) {
relative_start = Smi::cast(arg1)->value();
} else if (!arg1->IsUndefined()) {
return CallJsBuiltin("ArraySlice", args);
}
if (n_arguments > 1) {
Object* arg2 = args[2];
if (arg2->IsSmi()) {
relative_end = Smi::cast(arg2)->value();
} else if (!arg2->IsUndefined()) {
return CallJsBuiltin("ArraySlice", args);
}
}
}
// ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 6.
int k = (relative_start < 0) ? Max(len + relative_start, 0)
: Min(relative_start, len);
// ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 8.
int final = (relative_end < 0) ? Max(len + relative_end, 0)
: Min(relative_end, len);
// Calculate the length of result array.
int result_len = final - k;
if (result_len <= 0) {
return AllocateEmptyJSArray();
}
Object* result = AllocateJSArray();
if (result->IsFailure()) return result;
JSArray* result_array = JSArray::cast(result);
result = Heap::AllocateUninitializedFixedArray(result_len);
if (result->IsFailure()) return result;
FixedArray* result_elms = FixedArray::cast(result);
AssertNoAllocation no_gc;
CopyElements(&no_gc, result_elms, 0, elms, k, result_len);
// Set elements.
result_array->set_elements(result_elms);
// Set the length.
result_array->set_length(Smi::FromInt(result_len));
return result_array;
}
BUILTIN(ArraySplice) {
Object* receiver = *args.receiver();
Object* elms_obj = EnsureJSArrayWithWritableFastElements(receiver);
if (elms_obj->IsFailure()) return elms_obj;
if (elms_obj == NULL ||
!IsJSArrayFastElementMovingAllowed(JSArray::cast(receiver))) {
return CallJsBuiltin("ArraySplice", args);
}
FixedArray* elms = FixedArray::cast(elms_obj);
JSArray* array = JSArray::cast(receiver);
ASSERT(array->HasFastElements());
int len = Smi::cast(array->length())->value();
int n_arguments = args.length() - 1;
// Return empty array when no arguments are supplied.
if (n_arguments == 0) {
return AllocateEmptyJSArray();
}
int relative_start = 0;
Object* arg1 = args[1];
if (arg1->IsSmi()) {
relative_start = Smi::cast(arg1)->value();
} else if (!arg1->IsUndefined()) {
return CallJsBuiltin("ArraySplice", args);
}
int actual_start = (relative_start < 0) ? Max(len + relative_start, 0)
: Min(relative_start, len);
// SpiderMonkey, TraceMonkey and JSC treat the case where no delete count is
// given differently from when an undefined delete count is given.
// This does not follow ECMA-262, but we do the same for
// compatibility.
int delete_count = len;
if (n_arguments > 1) {
Object* arg2 = args[2];
if (arg2->IsSmi()) {
delete_count = Smi::cast(arg2)->value();
} else {
return CallJsBuiltin("ArraySplice", args);
}
}
int actual_delete_count = Min(Max(delete_count, 0), len - actual_start);
JSArray* result_array = NULL;
if (actual_delete_count == 0) {
Object* result = AllocateEmptyJSArray();
if (result->IsFailure()) return result;
result_array = JSArray::cast(result);
} else {
// Allocate result array.
Object* result = AllocateJSArray();
if (result->IsFailure()) return result;
result_array = JSArray::cast(result);
result = Heap::AllocateUninitializedFixedArray(actual_delete_count);
if (result->IsFailure()) return result;
FixedArray* result_elms = FixedArray::cast(result);
AssertNoAllocation no_gc;
// Fill newly created array.
CopyElements(&no_gc,
result_elms, 0,
elms, actual_start,
actual_delete_count);
// Set elements.
result_array->set_elements(result_elms);
// Set the length.
result_array->set_length(Smi::FromInt(actual_delete_count));
}
int item_count = (n_arguments > 1) ? (n_arguments - 2) : 0;
int new_length = len - actual_delete_count + item_count;
if (item_count < actual_delete_count) {
// Shrink the array.
const bool trim_array = !Heap::lo_space()->Contains(elms) &&
((actual_start + item_count) <
(len - actual_delete_count - actual_start));
if (trim_array) {
const int delta = actual_delete_count - item_count;
if (actual_start > 0) {
Object** start = elms->data_start();
memmove(start + delta, start, actual_start * kPointerSize);
}
elms = LeftTrimFixedArray(elms, delta);
array->set_elements(elms, SKIP_WRITE_BARRIER);
} else {
AssertNoAllocation no_gc;
MoveElements(&no_gc,
elms, actual_start + item_count,
elms, actual_start + actual_delete_count,
(len - actual_delete_count - actual_start));
FillWithHoles(elms, new_length, len);
}
} else if (item_count > actual_delete_count) {
// Currently fixed arrays cannot grow too big, so
// we should never hit this case.
ASSERT((item_count - actual_delete_count) <= (Smi::kMaxValue - len));
// Check if array need to grow.
if (new_length > elms->length()) {
// New backing storage is needed.
int capacity = new_length + (new_length >> 1) + 16;
Object* obj = Heap::AllocateUninitializedFixedArray(capacity);
if (obj->IsFailure()) return obj;
FixedArray* new_elms = FixedArray::cast(obj);
AssertNoAllocation no_gc;
// Copy the part before actual_start as is.
if (actual_start > 0) {
CopyElements(&no_gc, new_elms, 0, elms, 0, actual_start);
}
const int to_copy = len - actual_delete_count - actual_start;
if (to_copy > 0) {
CopyElements(&no_gc,
new_elms, actual_start + item_count,
elms, actual_start + actual_delete_count,
to_copy);
}
FillWithHoles(new_elms, new_length, capacity);
elms = new_elms;
array->set_elements(elms);
} else {
AssertNoAllocation no_gc;
MoveElements(&no_gc,
elms, actual_start + item_count,
elms, actual_start + actual_delete_count,
(len - actual_delete_count - actual_start));
}
}
AssertNoAllocation no_gc;
WriteBarrierMode mode = elms->GetWriteBarrierMode(no_gc);
for (int k = actual_start; k < actual_start + item_count; k++) {
elms->set(k, args[3 + k - actual_start], mode);
}
// Set the length.
array->set_length(Smi::FromInt(new_length));
return result_array;
}
BUILTIN(ArrayConcat) {
Context* global_context = Top::context()->global_context();
JSObject* array_proto =
JSObject::cast(global_context->array_function()->prototype());
if (!ArrayPrototypeHasNoElements(global_context, array_proto)) {
return CallJsBuiltin("ArrayConcat", args);
}
// Iterate through all the arguments performing checks
// and calculating total length.
int n_arguments = args.length();
int result_len = 0;
for (int i = 0; i < n_arguments; i++) {
Object* arg = args[i];
if (!arg->IsJSArray() || !JSArray::cast(arg)->HasFastElements()
|| JSArray::cast(arg)->GetPrototype() != array_proto) {
return CallJsBuiltin("ArrayConcat", args);
}
int len = Smi::cast(JSArray::cast(arg)->length())->value();
// We shouldn't overflow when adding another len.
const int kHalfOfMaxInt = 1 << (kBitsPerInt - 2);
STATIC_ASSERT(FixedArray::kMaxLength < kHalfOfMaxInt);
USE(kHalfOfMaxInt);
result_len += len;
ASSERT(result_len >= 0);
if (result_len > FixedArray::kMaxLength) {
return CallJsBuiltin("ArrayConcat", args);
}
}
if (result_len == 0) {
return AllocateEmptyJSArray();
}
// Allocate result.
Object* result = AllocateJSArray();
if (result->IsFailure()) return result;
JSArray* result_array = JSArray::cast(result);
result = Heap::AllocateUninitializedFixedArray(result_len);
if (result->IsFailure()) return result;
FixedArray* result_elms = FixedArray::cast(result);
// Copy data.
AssertNoAllocation no_gc;
int start_pos = 0;
for (int i = 0; i < n_arguments; i++) {
JSArray* array = JSArray::cast(args[i]);
int len = Smi::cast(array->length())->value();
if (len > 0) {
FixedArray* elms = FixedArray::cast(array->elements());
CopyElements(&no_gc, result_elms, start_pos, elms, 0, len);
start_pos += len;
}
}
ASSERT(start_pos == result_len);
// Set the length and elements.
result_array->set_length(Smi::FromInt(result_len));
result_array->set_elements(result_elms);
return result_array;
}
// -----------------------------------------------------------------------------
//
// Returns the holder JSObject if the function can legally be called
// with this receiver. Returns Heap::null_value() if the call is
// illegal. Any arguments that don't fit the expected type is
// overwritten with undefined. Arguments that do fit the expected
// type is overwritten with the object in the prototype chain that
// actually has that type.
static inline Object* TypeCheck(int argc,
Object** argv,
FunctionTemplateInfo* info) {
Object* recv = argv[0];
Object* sig_obj = info->signature();
if (sig_obj->IsUndefined()) return recv;
SignatureInfo* sig = SignatureInfo::cast(sig_obj);
// If necessary, check the receiver
Object* recv_type = sig->receiver();
Object* holder = recv;
if (!recv_type->IsUndefined()) {
for (; holder != Heap::null_value(); holder = holder->GetPrototype()) {
if (holder->IsInstanceOf(FunctionTemplateInfo::cast(recv_type))) {
break;
}
}
if (holder == Heap::null_value()) return holder;
}
Object* args_obj = sig->args();
// If there is no argument signature we're done
if (args_obj->IsUndefined()) return holder;
FixedArray* args = FixedArray::cast(args_obj);
int length = args->length();
if (argc <= length) length = argc - 1;
for (int i = 0; i < length; i++) {
Object* argtype = args->get(i);
if (argtype->IsUndefined()) continue;
Object** arg = &argv[-1 - i];
Object* current = *arg;
for (; current != Heap::null_value(); current = current->GetPrototype()) {
if (current->IsInstanceOf(FunctionTemplateInfo::cast(argtype))) {
*arg = current;
break;
}
}
if (current == Heap::null_value()) *arg = Heap::undefined_value();
}
return holder;
}
template <bool is_construct>
static Object* HandleApiCallHelper(
BuiltinArguments<NEEDS_CALLED_FUNCTION> args) {
ASSERT(is_construct == CalledAsConstructor());
HandleScope scope;
Handle<JSFunction> function = args.called_function();
ASSERT(function->shared()->IsApiFunction());
FunctionTemplateInfo* fun_data = function->shared()->get_api_func_data();
if (is_construct) {
Handle<FunctionTemplateInfo> desc(fun_data);
bool pending_exception = false;
Factory::ConfigureInstance(desc, Handle<JSObject>::cast(args.receiver()),
&pending_exception);
ASSERT(Top::has_pending_exception() == pending_exception);
if (pending_exception) return Failure::Exception();
fun_data = *desc;
}
Object* raw_holder = TypeCheck(args.length(), &args[0], fun_data);
if (raw_holder->IsNull()) {
// This function cannot be called with the given receiver. Abort!
Handle<Object> obj =
Factory::NewTypeError("illegal_invocation", HandleVector(&function, 1));
return Top::Throw(*obj);
}
Object* raw_call_data = fun_data->call_code();
if (!raw_call_data->IsUndefined()) {
CallHandlerInfo* call_data = CallHandlerInfo::cast(raw_call_data);
Object* callback_obj = call_data->callback();
v8::InvocationCallback callback =
v8::ToCData<v8::InvocationCallback>(callback_obj);
Object* data_obj = call_data->data();
Object* result;
Handle<Object> data_handle(data_obj);
v8::Local<v8::Value> data = v8::Utils::ToLocal(data_handle);
ASSERT(raw_holder->IsJSObject());
v8::Local<v8::Function> callee = v8::Utils::ToLocal(function);
Handle<JSObject> holder_handle(JSObject::cast(raw_holder));
v8::Local<v8::Object> holder = v8::Utils::ToLocal(holder_handle);
LOG(ApiObjectAccess("call", JSObject::cast(*args.receiver())));
v8::Arguments new_args = v8::ImplementationUtilities::NewArguments(
data,
holder,
callee,
is_construct,
reinterpret_cast<void**>(&args[0] - 1),
args.length() - 1);
v8::Handle<v8::Value> value;
{
// Leaving JavaScript.
VMState state(EXTERNAL);
#ifdef ENABLE_LOGGING_AND_PROFILING
state.set_external_callback(v8::ToCData<Address>(callback_obj));
#endif
value = callback(new_args);
}
if (value.IsEmpty()) {
result = Heap::undefined_value();
} else {
result = *reinterpret_cast<Object**>(*value);
}
RETURN_IF_SCHEDULED_EXCEPTION();
if (!is_construct || result->IsJSObject()) return result;
}
return *args.receiver();
}
BUILTIN(HandleApiCall) {
return HandleApiCallHelper<false>(args);
}
BUILTIN(HandleApiCallConstruct) {
return HandleApiCallHelper<true>(args);
}
#ifdef DEBUG
static void VerifyTypeCheck(Handle<JSObject> object,
Handle<JSFunction> function) {
ASSERT(function->shared()->IsApiFunction());
FunctionTemplateInfo* info = function->shared()->get_api_func_data();
if (info->signature()->IsUndefined()) return;
SignatureInfo* signature = SignatureInfo::cast(info->signature());
Object* receiver_type = signature->receiver();
if (receiver_type->IsUndefined()) return;
FunctionTemplateInfo* type = FunctionTemplateInfo::cast(receiver_type);
ASSERT(object->IsInstanceOf(type));
}
#endif
BUILTIN(FastHandleApiCall) {
ASSERT(!CalledAsConstructor());
const bool is_construct = false;
// We expect four more arguments: function, callback, call data, and holder.
const int args_length = args.length() - 4;
ASSERT(args_length >= 0);
Handle<JSFunction> function = args.at<JSFunction>(args_length);
Object* callback_obj = args[args_length + 1];
Handle<Object> data_handle = args.at<Object>(args_length + 2);
Handle<JSObject> checked_holder = args.at<JSObject>(args_length + 3);
#ifdef DEBUG
VerifyTypeCheck(checked_holder, function);
#endif
v8::Local<v8::Object> holder = v8::Utils::ToLocal(checked_holder);
v8::Local<v8::Function> callee = v8::Utils::ToLocal(function);
v8::InvocationCallback callback =
v8::ToCData<v8::InvocationCallback>(callback_obj);
v8::Local<v8::Value> data = v8::Utils::ToLocal(data_handle);
v8::Arguments new_args = v8::ImplementationUtilities::NewArguments(
data,
holder,
callee,
is_construct,
reinterpret_cast<void**>(&args[0] - 1),
args_length - 1);
HandleScope scope;
Object* result;
v8::Handle<v8::Value> value;
{
// Leaving JavaScript.
VMState state(EXTERNAL);
#ifdef ENABLE_LOGGING_AND_PROFILING
state.set_external_callback(v8::ToCData<Address>(callback_obj));
#endif
value = callback(new_args);
}
if (value.IsEmpty()) {
result = Heap::undefined_value();
} else {
result = *reinterpret_cast<Object**>(*value);
}
RETURN_IF_SCHEDULED_EXCEPTION();
return result;
}
// Helper function to handle calls to non-function objects created through the
// API. The object can be called as either a constructor (using new) or just as
// a function (without new).
static Object* HandleApiCallAsFunctionOrConstructor(
bool is_construct_call,
BuiltinArguments<NO_EXTRA_ARGUMENTS> args) {
// Non-functions are never called as constructors. Even if this is an object
// called as a constructor the delegate call is not a construct call.
ASSERT(!CalledAsConstructor());
Handle<Object> receiver = args.at<Object>(0);
// Get the object called.
JSObject* obj = JSObject::cast(*args.receiver());
// Get the invocation callback from the function descriptor that was
// used to create the called object.
ASSERT(obj->map()->has_instance_call_handler());
JSFunction* constructor = JSFunction::cast(obj->map()->constructor());
ASSERT(constructor->shared()->IsApiFunction());
Object* handler =
constructor->shared()->get_api_func_data()->instance_call_handler();
ASSERT(!handler->IsUndefined());
CallHandlerInfo* call_data = CallHandlerInfo::cast(handler);
Object* callback_obj = call_data->callback();
v8::InvocationCallback callback =
v8::ToCData<v8::InvocationCallback>(callback_obj);
// Get the data for the call and perform the callback.
Object* data_obj = call_data->data();
Object* result;
{ HandleScope scope;
v8::Local<v8::Object> self =
v8::Utils::ToLocal(Handle<JSObject>::cast(args.receiver()));
Handle<Object> data_handle(data_obj);
v8::Local<v8::Value> data = v8::Utils::ToLocal(data_handle);
Handle<JSFunction> callee_handle(constructor);
v8::Local<v8::Function> callee = v8::Utils::ToLocal(callee_handle);
LOG(ApiObjectAccess("call non-function", JSObject::cast(*args.receiver())));
v8::Arguments new_args = v8::ImplementationUtilities::NewArguments(
data,
self,
callee,
is_construct_call,
reinterpret_cast<void**>(&args[0] - 1),
args.length() - 1);
v8::Handle<v8::Value> value;
{
// Leaving JavaScript.
VMState state(EXTERNAL);
#ifdef ENABLE_LOGGING_AND_PROFILING
state.set_external_callback(v8::ToCData<Address>(callback_obj));
#endif
value = callback(new_args);
}
if (value.IsEmpty()) {
result = Heap::undefined_value();
} else {
result = *reinterpret_cast<Object**>(*value);
}
}
// Check for exceptions and return result.
RETURN_IF_SCHEDULED_EXCEPTION();
return result;
}
// Handle calls to non-function objects created through the API. This delegate
// function is used when the call is a normal function call.
BUILTIN(HandleApiCallAsFunction) {
return HandleApiCallAsFunctionOrConstructor(false, args);
}
// Handle calls to non-function objects created through the API. This delegate
// function is used when the call is a construct call.
BUILTIN(HandleApiCallAsConstructor) {
return HandleApiCallAsFunctionOrConstructor(true, args);
}
static void Generate_LoadIC_ArrayLength(MacroAssembler* masm) {
LoadIC::GenerateArrayLength(masm);
}
static void Generate_LoadIC_StringLength(MacroAssembler* masm) {
LoadIC::GenerateStringLength(masm);
}
static void Generate_LoadIC_FunctionPrototype(MacroAssembler* masm) {
LoadIC::GenerateFunctionPrototype(masm);
}
static void Generate_LoadIC_Initialize(MacroAssembler* masm) {
LoadIC::GenerateInitialize(masm);
}
static void Generate_LoadIC_PreMonomorphic(MacroAssembler* masm) {
LoadIC::GeneratePreMonomorphic(masm);
}
static void Generate_LoadIC_Miss(MacroAssembler* masm) {
LoadIC::GenerateMiss(masm);
}
static void Generate_LoadIC_Megamorphic(MacroAssembler* masm) {
LoadIC::GenerateMegamorphic(masm);
}
static void Generate_LoadIC_Normal(MacroAssembler* masm) {
LoadIC::GenerateNormal(masm);
}
static void Generate_KeyedLoadIC_Initialize(MacroAssembler* masm) {
KeyedLoadIC::GenerateInitialize(masm);
}
static void Generate_KeyedLoadIC_Miss(MacroAssembler* masm) {
KeyedLoadIC::GenerateMiss(masm);
}
static void Generate_KeyedLoadIC_Generic(MacroAssembler* masm) {
KeyedLoadIC::GenerateGeneric(masm);
}
static void Generate_KeyedLoadIC_String(MacroAssembler* masm) {
KeyedLoadIC::GenerateString(masm);
}
static void Generate_KeyedLoadIC_ExternalByteArray(MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalByteArray);
}
static void Generate_KeyedLoadIC_ExternalUnsignedByteArray(
MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalUnsignedByteArray);
}
static void Generate_KeyedLoadIC_ExternalShortArray(MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalShortArray);
}
static void Generate_KeyedLoadIC_ExternalUnsignedShortArray(
MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalUnsignedShortArray);
}
static void Generate_KeyedLoadIC_ExternalIntArray(MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalIntArray);
}
static void Generate_KeyedLoadIC_ExternalUnsignedIntArray(
MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalUnsignedIntArray);
}
static void Generate_KeyedLoadIC_ExternalFloatArray(MacroAssembler* masm) {
KeyedLoadIC::GenerateExternalArray(masm, kExternalFloatArray);
}
static void Generate_KeyedLoadIC_PreMonomorphic(MacroAssembler* masm) {
KeyedLoadIC::GeneratePreMonomorphic(masm);
}
static void Generate_KeyedLoadIC_IndexedInterceptor(MacroAssembler* masm) {
KeyedLoadIC::GenerateIndexedInterceptor(masm);
}
static void Generate_StoreIC_Initialize(MacroAssembler* masm) {
StoreIC::GenerateInitialize(masm);
}
static void Generate_StoreIC_Miss(MacroAssembler* masm) {
StoreIC::GenerateMiss(masm);
}
static void Generate_StoreIC_Normal(MacroAssembler* masm) {
StoreIC::GenerateNormal(masm);
}
static void Generate_StoreIC_Megamorphic(MacroAssembler* masm) {
StoreIC::GenerateMegamorphic(masm);
}
static void Generate_StoreIC_ArrayLength(MacroAssembler* masm) {
StoreIC::GenerateArrayLength(masm);
}
static void Generate_KeyedStoreIC_Generic(MacroAssembler* masm) {
KeyedStoreIC::GenerateGeneric(masm);
}
static void Generate_KeyedStoreIC_ExternalByteArray(MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalByteArray);
}
static void Generate_KeyedStoreIC_ExternalUnsignedByteArray(
MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalUnsignedByteArray);
}
static void Generate_KeyedStoreIC_ExternalShortArray(MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalShortArray);
}
static void Generate_KeyedStoreIC_ExternalUnsignedShortArray(
MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalUnsignedShortArray);
}
static void Generate_KeyedStoreIC_ExternalIntArray(MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalIntArray);
}
static void Generate_KeyedStoreIC_ExternalUnsignedIntArray(
MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalUnsignedIntArray);
}
static void Generate_KeyedStoreIC_ExternalFloatArray(MacroAssembler* masm) {
KeyedStoreIC::GenerateExternalArray(masm, kExternalFloatArray);
}
static void Generate_KeyedStoreIC_Miss(MacroAssembler* masm) {
KeyedStoreIC::GenerateMiss(masm);
}
static void Generate_KeyedStoreIC_Initialize(MacroAssembler* masm) {
KeyedStoreIC::GenerateInitialize(masm);
}
#ifdef ENABLE_DEBUGGER_SUPPORT
static void Generate_LoadIC_DebugBreak(MacroAssembler* masm) {
Debug::GenerateLoadICDebugBreak(masm);
}
static void Generate_StoreIC_DebugBreak(MacroAssembler* masm) {
Debug::GenerateStoreICDebugBreak(masm);
}
static void Generate_KeyedLoadIC_DebugBreak(MacroAssembler* masm) {
Debug::GenerateKeyedLoadICDebugBreak(masm);
}
static void Generate_KeyedStoreIC_DebugBreak(MacroAssembler* masm) {
Debug::GenerateKeyedStoreICDebugBreak(masm);
}
static void Generate_ConstructCall_DebugBreak(MacroAssembler* masm) {
Debug::GenerateConstructCallDebugBreak(masm);
}
static void Generate_Return_DebugBreak(MacroAssembler* masm) {
Debug::GenerateReturnDebugBreak(masm);
}
static void Generate_StubNoRegisters_DebugBreak(MacroAssembler* masm) {
Debug::GenerateStubNoRegistersDebugBreak(masm);
}
static void Generate_Slot_DebugBreak(MacroAssembler* masm) {
Debug::GenerateSlotDebugBreak(masm);
}
static void Generate_PlainReturn_LiveEdit(MacroAssembler* masm) {
Debug::GeneratePlainReturnLiveEdit(masm);
}
static void Generate_FrameDropper_LiveEdit(MacroAssembler* masm) {
Debug::GenerateFrameDropperLiveEdit(masm);
}
#endif
Object* Builtins::builtins_[builtin_count] = { NULL, };
const char* Builtins::names_[builtin_count] = { NULL, };
#define DEF_ENUM_C(name, ignore) FUNCTION_ADDR(Builtin_##name),
Address Builtins::c_functions_[cfunction_count] = {
BUILTIN_LIST_C(DEF_ENUM_C)
};
#undef DEF_ENUM_C
#define DEF_JS_NAME(name, ignore) #name,
#define DEF_JS_ARGC(ignore, argc) argc,
const char* Builtins::javascript_names_[id_count] = {
BUILTINS_LIST_JS(DEF_JS_NAME)
};
int Builtins::javascript_argc_[id_count] = {
BUILTINS_LIST_JS(DEF_JS_ARGC)
};
#undef DEF_JS_NAME
#undef DEF_JS_ARGC
static bool is_initialized = false;
void Builtins::Setup(bool create_heap_objects) {
ASSERT(!is_initialized);
// Create a scope for the handles in the builtins.
HandleScope scope;
struct BuiltinDesc {
byte* generator;
byte* c_code;
const char* s_name; // name is only used for generating log information.
int name;
Code::Flags flags;
BuiltinExtraArguments extra_args;
};
#define DEF_FUNCTION_PTR_C(name, extra_args) \
{ FUNCTION_ADDR(Generate_Adaptor), \
FUNCTION_ADDR(Builtin_##name), \
#name, \
c_##name, \
Code::ComputeFlags(Code::BUILTIN), \
extra_args \
},
#define DEF_FUNCTION_PTR_A(name, kind, state) \
{ FUNCTION_ADDR(Generate_##name), \
NULL, \
#name, \
name, \
Code::ComputeFlags(Code::kind, NOT_IN_LOOP, state), \
NO_EXTRA_ARGUMENTS \
},
// Define array of pointers to generators and C builtin functions.
static BuiltinDesc functions[] = {
BUILTIN_LIST_C(DEF_FUNCTION_PTR_C)
BUILTIN_LIST_A(DEF_FUNCTION_PTR_A)
BUILTIN_LIST_DEBUG_A(DEF_FUNCTION_PTR_A)
// Terminator:
{ NULL, NULL, NULL, builtin_count, static_cast<Code::Flags>(0),
NO_EXTRA_ARGUMENTS }
};
#undef DEF_FUNCTION_PTR_C
#undef DEF_FUNCTION_PTR_A
// For now we generate builtin adaptor code into a stack-allocated
// buffer, before copying it into individual code objects.
byte buffer[4*KB];
// Traverse the list of builtins and generate an adaptor in a
// separate code object for each one.
for (int i = 0; i < builtin_count; i++) {
if (create_heap_objects) {
MacroAssembler masm(buffer, sizeof buffer);
// Generate the code/adaptor.
typedef void (*Generator)(MacroAssembler*, int, BuiltinExtraArguments);
Generator g = FUNCTION_CAST<Generator>(functions[i].generator);
// We pass all arguments to the generator, but it may not use all of
// them. This works because the first arguments are on top of the
// stack.
g(&masm, functions[i].name, functions[i].extra_args);
// Move the code into the object heap.
CodeDesc desc;
masm.GetCode(&desc);
Code::Flags flags = functions[i].flags;
Object* code;
{
// During startup it's OK to always allocate and defer GC to later.
// This simplifies things because we don't need to retry.
AlwaysAllocateScope __scope__;
code = Heap::CreateCode(desc, flags, masm.CodeObject());
if (code->IsFailure()) {
v8::internal::V8::FatalProcessOutOfMemory("CreateCode");
}
}
// Log the event and add the code to the builtins array.
PROFILE(CodeCreateEvent(Logger::BUILTIN_TAG,
Code::cast(code), functions[i].s_name));
builtins_[i] = code;
#ifdef ENABLE_DISASSEMBLER
if (FLAG_print_builtin_code) {
PrintF("Builtin: %s\n", functions[i].s_name);
Code::cast(code)->Disassemble(functions[i].s_name);
PrintF("\n");
}
#endif
} else {
// Deserializing. The values will be filled in during IterateBuiltins.
builtins_[i] = NULL;
}
names_[i] = functions[i].s_name;
}
// Mark as initialized.
is_initialized = true;
}
void Builtins::TearDown() {
is_initialized = false;
}
void Builtins::IterateBuiltins(ObjectVisitor* v) {
v->VisitPointers(&builtins_[0], &builtins_[0] + builtin_count);
}
const char* Builtins::Lookup(byte* pc) {
if (is_initialized) { // may be called during initialization (disassembler!)
for (int i = 0; i < builtin_count; i++) {
Code* entry = Code::cast(builtins_[i]);
if (entry->contains(pc)) {
return names_[i];
}
}
}
return NULL;
}
} } // namespace v8::internal