// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/v8.h"
#include "src/accessors.h"
#include "src/allocation-site-scopes.h"
#include "src/api.h"
#include "src/arguments.h"
#include "src/base/bits.h"
#include "src/bootstrapper.h"
#include "src/code-stubs.h"
#include "src/codegen.h"
#include "src/cpu-profiler.h"
#include "src/date.h"
#include "src/debug.h"
#include "src/deoptimizer.h"
#include "src/elements.h"
#include "src/execution.h"
#include "src/field-index-inl.h"
#include "src/field-index.h"
#include "src/full-codegen.h"
#include "src/heap/mark-compact.h"
#include "src/heap/objects-visiting-inl.h"
#include "src/hydrogen.h"
#include "src/ic/ic.h"
#include "src/isolate-inl.h"
#include "src/log.h"
#include "src/lookup.h"
#include "src/macro-assembler.h"
#include "src/objects-inl.h"
#include "src/prototype.h"
#include "src/safepoint-table.h"
#include "src/string-search.h"
#include "src/string-stream.h"
#include "src/utils.h"
#ifdef ENABLE_DISASSEMBLER
#include "src/disasm.h"
#include "src/disassembler.h"
#endif
namespace v8 {
namespace internal {
Handle<HeapType> Object::OptimalType(Isolate* isolate,
Representation representation) {
if (representation.IsNone()) return HeapType::None(isolate);
if (FLAG_track_field_types) {
if (representation.IsHeapObject() && IsHeapObject()) {
// We can track only JavaScript objects with stable maps.
Handle<Map> map(HeapObject::cast(this)->map(), isolate);
if (map->is_stable() &&
map->instance_type() >= FIRST_NONCALLABLE_SPEC_OBJECT_TYPE &&
map->instance_type() <= LAST_NONCALLABLE_SPEC_OBJECT_TYPE) {
return HeapType::Class(map, isolate);
}
}
}
return HeapType::Any(isolate);
}
MaybeHandle<JSReceiver> Object::ToObject(Isolate* isolate,
Handle<Object> object,
Handle<Context> native_context) {
if (object->IsJSReceiver()) return Handle<JSReceiver>::cast(object);
Handle<JSFunction> constructor;
if (object->IsNumber()) {
constructor = handle(native_context->number_function(), isolate);
} else if (object->IsBoolean()) {
constructor = handle(native_context->boolean_function(), isolate);
} else if (object->IsString()) {
constructor = handle(native_context->string_function(), isolate);
} else if (object->IsSymbol()) {
constructor = handle(native_context->symbol_function(), isolate);
} else {
return MaybeHandle<JSReceiver>();
}
Handle<JSObject> result = isolate->factory()->NewJSObject(constructor);
Handle<JSValue>::cast(result)->set_value(*object);
return result;
}
bool Object::BooleanValue() {
if (IsBoolean()) return IsTrue();
if (IsSmi()) return Smi::cast(this)->value() != 0;
if (IsUndefined() || IsNull()) return false;
if (IsUndetectableObject()) return false; // Undetectable object is false.
if (IsString()) return String::cast(this)->length() != 0;
if (IsHeapNumber()) return HeapNumber::cast(this)->HeapNumberBooleanValue();
return true;
}
bool Object::IsCallable() const {
const Object* fun = this;
while (fun->IsJSFunctionProxy()) {
fun = JSFunctionProxy::cast(fun)->call_trap();
}
return fun->IsJSFunction() ||
(fun->IsHeapObject() &&
HeapObject::cast(fun)->map()->has_instance_call_handler());
}
MaybeHandle<Object> Object::GetProperty(LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::JSPROXY:
return JSProxy::GetPropertyWithHandler(it->GetHolder<JSProxy>(),
it->GetReceiver(), it->name());
case LookupIterator::INTERCEPTOR: {
MaybeHandle<Object> maybe_result = JSObject::GetPropertyWithInterceptor(
it->GetHolder<JSObject>(), it->GetReceiver(), it->name());
if (!maybe_result.is_null()) return maybe_result;
if (it->isolate()->has_pending_exception()) return maybe_result;
break;
}
case LookupIterator::ACCESS_CHECK:
if (it->HasAccess(v8::ACCESS_GET)) break;
return JSObject::GetPropertyWithFailedAccessCheck(it);
case LookupIterator::ACCESSOR:
return GetPropertyWithAccessor(it->GetReceiver(), it->name(),
it->GetHolder<JSObject>(),
it->GetAccessors());
case LookupIterator::DATA:
return it->GetDataValue();
}
}
return it->factory()->undefined_value();
}
Handle<Object> JSObject::GetDataProperty(Handle<JSObject> object,
Handle<Name> key) {
LookupIterator it(object, key,
LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR);
return GetDataProperty(&it);
}
Handle<Object> JSObject::GetDataProperty(LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::INTERCEPTOR:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::ACCESS_CHECK:
if (it->HasAccess(v8::ACCESS_GET)) continue;
// Fall through.
case LookupIterator::JSPROXY:
it->NotFound();
return it->isolate()->factory()->undefined_value();
case LookupIterator::ACCESSOR:
// TODO(verwaest): For now this doesn't call into
// ExecutableAccessorInfo, since clients don't need it. Update once
// relevant.
it->NotFound();
return it->isolate()->factory()->undefined_value();
case LookupIterator::DATA:
return it->GetDataValue();
}
}
return it->isolate()->factory()->undefined_value();
}
bool Object::ToInt32(int32_t* value) {
if (IsSmi()) {
*value = Smi::cast(this)->value();
return true;
}
if (IsHeapNumber()) {
double num = HeapNumber::cast(this)->value();
if (FastI2D(FastD2I(num)) == num) {
*value = FastD2I(num);
return true;
}
}
return false;
}
bool Object::ToUint32(uint32_t* value) {
if (IsSmi()) {
int num = Smi::cast(this)->value();
if (num >= 0) {
*value = static_cast<uint32_t>(num);
return true;
}
}
if (IsHeapNumber()) {
double num = HeapNumber::cast(this)->value();
if (num >= 0 && FastUI2D(FastD2UI(num)) == num) {
*value = FastD2UI(num);
return true;
}
}
return false;
}
bool FunctionTemplateInfo::IsTemplateFor(Object* object) {
if (!object->IsHeapObject()) return false;
return IsTemplateFor(HeapObject::cast(object)->map());
}
bool FunctionTemplateInfo::IsTemplateFor(Map* map) {
// There is a constraint on the object; check.
if (!map->IsJSObjectMap()) return false;
// Fetch the constructor function of the object.
Object* cons_obj = map->constructor();
if (!cons_obj->IsJSFunction()) return false;
JSFunction* fun = JSFunction::cast(cons_obj);
// Iterate through the chain of inheriting function templates to
// see if the required one occurs.
for (Object* type = fun->shared()->function_data();
type->IsFunctionTemplateInfo();
type = FunctionTemplateInfo::cast(type)->parent_template()) {
if (type == this) return true;
}
// Didn't find the required type in the inheritance chain.
return false;
}
template<typename To>
static inline To* CheckedCast(void *from) {
uintptr_t temp = reinterpret_cast<uintptr_t>(from);
DCHECK(temp % sizeof(To) == 0);
return reinterpret_cast<To*>(temp);
}
static Handle<Object> PerformCompare(const BitmaskCompareDescriptor& descriptor,
char* ptr,
Isolate* isolate) {
uint32_t bitmask = descriptor.bitmask;
uint32_t compare_value = descriptor.compare_value;
uint32_t value;
switch (descriptor.size) {
case 1:
value = static_cast<uint32_t>(*CheckedCast<uint8_t>(ptr));
compare_value &= 0xff;
bitmask &= 0xff;
break;
case 2:
value = static_cast<uint32_t>(*CheckedCast<uint16_t>(ptr));
compare_value &= 0xffff;
bitmask &= 0xffff;
break;
case 4:
value = *CheckedCast<uint32_t>(ptr);
break;
default:
UNREACHABLE();
return isolate->factory()->undefined_value();
}
return isolate->factory()->ToBoolean(
(bitmask & value) == (bitmask & compare_value));
}
static Handle<Object> PerformCompare(const PointerCompareDescriptor& descriptor,
char* ptr,
Isolate* isolate) {
uintptr_t compare_value =
reinterpret_cast<uintptr_t>(descriptor.compare_value);
uintptr_t value = *CheckedCast<uintptr_t>(ptr);
return isolate->factory()->ToBoolean(compare_value == value);
}
static Handle<Object> GetPrimitiveValue(
const PrimitiveValueDescriptor& descriptor,
char* ptr,
Isolate* isolate) {
int32_t int32_value = 0;
switch (descriptor.data_type) {
case kDescriptorInt8Type:
int32_value = *CheckedCast<int8_t>(ptr);
break;
case kDescriptorUint8Type:
int32_value = *CheckedCast<uint8_t>(ptr);
break;
case kDescriptorInt16Type:
int32_value = *CheckedCast<int16_t>(ptr);
break;
case kDescriptorUint16Type:
int32_value = *CheckedCast<uint16_t>(ptr);
break;
case kDescriptorInt32Type:
int32_value = *CheckedCast<int32_t>(ptr);
break;
case kDescriptorUint32Type: {
uint32_t value = *CheckedCast<uint32_t>(ptr);
AllowHeapAllocation allow_gc;
return isolate->factory()->NewNumberFromUint(value);
}
case kDescriptorBoolType: {
uint8_t byte = *CheckedCast<uint8_t>(ptr);
return isolate->factory()->ToBoolean(
byte & (0x1 << descriptor.bool_offset));
}
case kDescriptorFloatType: {
float value = *CheckedCast<float>(ptr);
AllowHeapAllocation allow_gc;
return isolate->factory()->NewNumber(value);
}
case kDescriptorDoubleType: {
double value = *CheckedCast<double>(ptr);
AllowHeapAllocation allow_gc;
return isolate->factory()->NewNumber(value);
}
}
AllowHeapAllocation allow_gc;
return isolate->factory()->NewNumberFromInt(int32_value);
}
static Handle<Object> GetDeclaredAccessorProperty(
Handle<Object> receiver,
Handle<DeclaredAccessorInfo> info,
Isolate* isolate) {
DisallowHeapAllocation no_gc;
char* current = reinterpret_cast<char*>(*receiver);
DeclaredAccessorDescriptorIterator iterator(info->descriptor());
while (true) {
const DeclaredAccessorDescriptorData* data = iterator.Next();
switch (data->type) {
case kDescriptorReturnObject: {
DCHECK(iterator.Complete());
current = *CheckedCast<char*>(current);
return handle(*CheckedCast<Object*>(current), isolate);
}
case kDescriptorPointerDereference:
DCHECK(!iterator.Complete());
current = *reinterpret_cast<char**>(current);
break;
case kDescriptorPointerShift:
DCHECK(!iterator.Complete());
current += data->pointer_shift_descriptor.byte_offset;
break;
case kDescriptorObjectDereference: {
DCHECK(!iterator.Complete());
Object* object = CheckedCast<Object>(current);
int field = data->object_dereference_descriptor.internal_field;
Object* smi = JSObject::cast(object)->GetInternalField(field);
DCHECK(smi->IsSmi());
current = reinterpret_cast<char*>(smi);
break;
}
case kDescriptorBitmaskCompare:
DCHECK(iterator.Complete());
return PerformCompare(data->bitmask_compare_descriptor,
current,
isolate);
case kDescriptorPointerCompare:
DCHECK(iterator.Complete());
return PerformCompare(data->pointer_compare_descriptor,
current,
isolate);
case kDescriptorPrimitiveValue:
DCHECK(iterator.Complete());
return GetPrimitiveValue(data->primitive_value_descriptor,
current,
isolate);
}
}
UNREACHABLE();
return isolate->factory()->undefined_value();
}
Handle<FixedArray> JSObject::EnsureWritableFastElements(
Handle<JSObject> object) {
DCHECK(object->HasFastSmiOrObjectElements());
Isolate* isolate = object->GetIsolate();
Handle<FixedArray> elems(FixedArray::cast(object->elements()), isolate);
if (elems->map() != isolate->heap()->fixed_cow_array_map()) return elems;
Handle<FixedArray> writable_elems = isolate->factory()->CopyFixedArrayWithMap(
elems, isolate->factory()->fixed_array_map());
object->set_elements(*writable_elems);
isolate->counters()->cow_arrays_converted()->Increment();
return writable_elems;
}
MaybeHandle<Object> JSProxy::GetPropertyWithHandler(Handle<JSProxy> proxy,
Handle<Object> receiver,
Handle<Name> name) {
Isolate* isolate = proxy->GetIsolate();
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) return isolate->factory()->undefined_value();
Handle<Object> args[] = { receiver, name };
return CallTrap(
proxy, "get", isolate->derived_get_trap(), arraysize(args), args);
}
MaybeHandle<Object> Object::GetPropertyWithAccessor(Handle<Object> receiver,
Handle<Name> name,
Handle<JSObject> holder,
Handle<Object> structure) {
Isolate* isolate = name->GetIsolate();
DCHECK(!structure->IsForeign());
// api style callbacks.
if (structure->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(structure);
if (!info->IsCompatibleReceiver(*receiver)) {
Handle<Object> args[2] = { name, receiver };
THROW_NEW_ERROR(isolate,
NewTypeError("incompatible_method_receiver",
HandleVector(args, arraysize(args))),
Object);
}
if (structure->IsDeclaredAccessorInfo()) {
return GetDeclaredAccessorProperty(
receiver,
Handle<DeclaredAccessorInfo>::cast(structure),
isolate);
}
Handle<ExecutableAccessorInfo> data =
Handle<ExecutableAccessorInfo>::cast(structure);
v8::AccessorNameGetterCallback call_fun =
v8::ToCData<v8::AccessorNameGetterCallback>(data->getter());
if (call_fun == NULL) return isolate->factory()->undefined_value();
LOG(isolate, ApiNamedPropertyAccess("load", *holder, *name));
PropertyCallbackArguments args(isolate, data->data(), *receiver, *holder);
v8::Handle<v8::Value> result =
args.Call(call_fun, v8::Utils::ToLocal(name));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (result.IsEmpty()) {
return isolate->factory()->undefined_value();
}
Handle<Object> return_value = v8::Utils::OpenHandle(*result);
return_value->VerifyApiCallResultType();
// Rebox handle before return.
return handle(*return_value, isolate);
}
// __defineGetter__ callback
Handle<Object> getter(Handle<AccessorPair>::cast(structure)->getter(),
isolate);
if (getter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return Object::GetPropertyWithDefinedGetter(
receiver, Handle<JSReceiver>::cast(getter));
}
// Getter is not a function.
return isolate->factory()->undefined_value();
}
bool AccessorInfo::IsCompatibleReceiverType(Isolate* isolate,
Handle<AccessorInfo> info,
Handle<HeapType> type) {
if (!info->HasExpectedReceiverType()) return true;
Handle<Map> map = IC::TypeToMap(*type, isolate);
if (!map->IsJSObjectMap()) return false;
return FunctionTemplateInfo::cast(info->expected_receiver_type())
->IsTemplateFor(*map);
}
MaybeHandle<Object> Object::SetPropertyWithAccessor(
Handle<Object> receiver, Handle<Name> name, Handle<Object> value,
Handle<JSObject> holder, Handle<Object> structure, StrictMode strict_mode) {
Isolate* isolate = name->GetIsolate();
// We should never get here to initialize a const with the hole
// value since a const declaration would conflict with the setter.
DCHECK(!structure->IsForeign());
if (structure->IsExecutableAccessorInfo()) {
// Don't call executable accessor setters with non-JSObject receivers.
if (!receiver->IsJSObject()) return value;
// api style callbacks
ExecutableAccessorInfo* info = ExecutableAccessorInfo::cast(*structure);
if (!info->IsCompatibleReceiver(*receiver)) {
Handle<Object> args[2] = { name, receiver };
THROW_NEW_ERROR(isolate,
NewTypeError("incompatible_method_receiver",
HandleVector(args, arraysize(args))),
Object);
}
Object* call_obj = info->setter();
v8::AccessorNameSetterCallback call_fun =
v8::ToCData<v8::AccessorNameSetterCallback>(call_obj);
if (call_fun == NULL) return value;
LOG(isolate, ApiNamedPropertyAccess("store", *holder, *name));
PropertyCallbackArguments args(isolate, info->data(), *receiver, *holder);
args.Call(call_fun,
v8::Utils::ToLocal(name),
v8::Utils::ToLocal(value));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return value;
}
if (structure->IsAccessorPair()) {
Handle<Object> setter(AccessorPair::cast(*structure)->setter(), isolate);
if (setter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return SetPropertyWithDefinedSetter(
receiver, Handle<JSReceiver>::cast(setter), value);
} else {
if (strict_mode == SLOPPY) return value;
Handle<Object> args[2] = { name, holder };
THROW_NEW_ERROR(
isolate, NewTypeError("no_setter_in_callback", HandleVector(args, 2)),
Object);
}
}
// TODO(dcarney): Handle correctly.
if (structure->IsDeclaredAccessorInfo()) {
return value;
}
UNREACHABLE();
return MaybeHandle<Object>();
}
MaybeHandle<Object> Object::GetPropertyWithDefinedGetter(
Handle<Object> receiver,
Handle<JSReceiver> getter) {
Isolate* isolate = getter->GetIsolate();
Debug* debug = isolate->debug();
// Handle stepping into a getter if step into is active.
// TODO(rossberg): should this apply to getters that are function proxies?
if (debug->StepInActive() && getter->IsJSFunction()) {
debug->HandleStepIn(
Handle<JSFunction>::cast(getter), Handle<Object>::null(), 0, false);
}
return Execution::Call(isolate, getter, receiver, 0, NULL, true);
}
MaybeHandle<Object> Object::SetPropertyWithDefinedSetter(
Handle<Object> receiver,
Handle<JSReceiver> setter,
Handle<Object> value) {
Isolate* isolate = setter->GetIsolate();
Debug* debug = isolate->debug();
// Handle stepping into a setter if step into is active.
// TODO(rossberg): should this apply to getters that are function proxies?
if (debug->StepInActive() && setter->IsJSFunction()) {
debug->HandleStepIn(
Handle<JSFunction>::cast(setter), Handle<Object>::null(), 0, false);
}
Handle<Object> argv[] = { value };
RETURN_ON_EXCEPTION(isolate, Execution::Call(isolate, setter, receiver,
arraysize(argv), argv, true),
Object);
return value;
}
static bool FindAllCanReadHolder(LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
if (it->state() == LookupIterator::ACCESSOR) {
Handle<Object> accessors = it->GetAccessors();
if (accessors->IsAccessorInfo()) {
if (AccessorInfo::cast(*accessors)->all_can_read()) return true;
}
}
}
return false;
}
MaybeHandle<Object> JSObject::GetPropertyWithFailedAccessCheck(
LookupIterator* it) {
Handle<JSObject> checked = it->GetHolder<JSObject>();
if (FindAllCanReadHolder(it)) {
return GetPropertyWithAccessor(it->GetReceiver(), it->name(),
it->GetHolder<JSObject>(),
it->GetAccessors());
}
it->isolate()->ReportFailedAccessCheck(checked, v8::ACCESS_GET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(it->isolate(), Object);
return it->factory()->undefined_value();
}
Maybe<PropertyAttributes> JSObject::GetPropertyAttributesWithFailedAccessCheck(
LookupIterator* it) {
Handle<JSObject> checked = it->GetHolder<JSObject>();
if (FindAllCanReadHolder(it))
return maybe(it->property_details().attributes());
it->isolate()->ReportFailedAccessCheck(checked, v8::ACCESS_HAS);
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(it->isolate(),
Maybe<PropertyAttributes>());
return maybe(ABSENT);
}
static bool FindAllCanWriteHolder(LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
if (it->state() == LookupIterator::ACCESSOR) {
Handle<Object> accessors = it->GetAccessors();
if (accessors->IsAccessorInfo()) {
if (AccessorInfo::cast(*accessors)->all_can_write()) return true;
}
}
}
return false;
}
MaybeHandle<Object> JSObject::SetPropertyWithFailedAccessCheck(
LookupIterator* it, Handle<Object> value, StrictMode strict_mode) {
Handle<JSObject> checked = it->GetHolder<JSObject>();
if (FindAllCanWriteHolder(it)) {
return SetPropertyWithAccessor(it->GetReceiver(), it->name(), value,
it->GetHolder<JSObject>(),
it->GetAccessors(), strict_mode);
}
it->isolate()->ReportFailedAccessCheck(checked, v8::ACCESS_SET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(it->isolate(), Object);
return value;
}
void JSObject::SetNormalizedProperty(Handle<JSObject> object,
Handle<Name> name,
Handle<Object> value,
PropertyDetails details) {
DCHECK(!object->HasFastProperties());
Handle<NameDictionary> property_dictionary(object->property_dictionary());
if (!name->IsUniqueName()) {
name = object->GetIsolate()->factory()->InternalizeString(
Handle<String>::cast(name));
}
int entry = property_dictionary->FindEntry(name);
if (entry == NameDictionary::kNotFound) {
Handle<Object> store_value = value;
if (object->IsGlobalObject()) {
store_value = object->GetIsolate()->factory()->NewPropertyCell(value);
}
property_dictionary = NameDictionary::Add(
property_dictionary, name, store_value, details);
object->set_properties(*property_dictionary);
return;
}
PropertyDetails original_details = property_dictionary->DetailsAt(entry);
int enumeration_index;
// Preserve the enumeration index unless the property was deleted.
if (original_details.IsDeleted()) {
enumeration_index = property_dictionary->NextEnumerationIndex();
property_dictionary->SetNextEnumerationIndex(enumeration_index + 1);
} else {
enumeration_index = original_details.dictionary_index();
DCHECK(enumeration_index > 0);
}
details = PropertyDetails(
details.attributes(), details.type(), enumeration_index);
if (object->IsGlobalObject()) {
Handle<PropertyCell> cell(
PropertyCell::cast(property_dictionary->ValueAt(entry)));
PropertyCell::SetValueInferType(cell, value);
// Please note we have to update the property details.
property_dictionary->DetailsAtPut(entry, details);
} else {
property_dictionary->SetEntry(entry, name, value, details);
}
}
Handle<Object> JSObject::DeleteNormalizedProperty(Handle<JSObject> object,
Handle<Name> name,
DeleteMode mode) {
DCHECK(!object->HasFastProperties());
Isolate* isolate = object->GetIsolate();
Handle<NameDictionary> dictionary(object->property_dictionary());
int entry = dictionary->FindEntry(name);
if (entry != NameDictionary::kNotFound) {
// If we have a global object set the cell to the hole.
if (object->IsGlobalObject()) {
PropertyDetails details = dictionary->DetailsAt(entry);
if (!details.IsConfigurable()) {
if (mode != FORCE_DELETION) return isolate->factory()->false_value();
// When forced to delete global properties, we have to make a
// map change to invalidate any ICs that think they can load
// from the non-configurable cell without checking if it contains
// the hole value.
Handle<Map> new_map = Map::CopyDropDescriptors(handle(object->map()));
DCHECK(new_map->is_dictionary_map());
JSObject::MigrateToMap(object, new_map);
}
Handle<PropertyCell> cell(PropertyCell::cast(dictionary->ValueAt(entry)));
Handle<Object> value = isolate->factory()->the_hole_value();
PropertyCell::SetValueInferType(cell, value);
dictionary->DetailsAtPut(entry, details.AsDeleted());
} else {
Handle<Object> deleted(
NameDictionary::DeleteProperty(dictionary, entry, mode));
if (*deleted == isolate->heap()->true_value()) {
Handle<NameDictionary> new_properties =
NameDictionary::Shrink(dictionary, name);
object->set_properties(*new_properties);
}
return deleted;
}
}
return isolate->factory()->true_value();
}
bool JSObject::IsDirty() {
Object* cons_obj = map()->constructor();
if (!cons_obj->IsJSFunction())
return true;
JSFunction* fun = JSFunction::cast(cons_obj);
if (!fun->shared()->IsApiFunction())
return true;
// If the object is fully fast case and has the same map it was
// created with then no changes can have been made to it.
return map() != fun->initial_map()
|| !HasFastObjectElements()
|| !HasFastProperties();
}
MaybeHandle<Object> Object::GetElementWithReceiver(Isolate* isolate,
Handle<Object> object,
Handle<Object> receiver,
uint32_t index) {
if (object->IsUndefined()) {
// TODO(verwaest): Why is this check here?
UNREACHABLE();
return isolate->factory()->undefined_value();
}
// Iterate up the prototype chain until an element is found or the null
// prototype is encountered.
for (PrototypeIterator iter(isolate, object,
object->IsJSProxy() || object->IsJSObject()
? PrototypeIterator::START_AT_RECEIVER
: PrototypeIterator::START_AT_PROTOTYPE);
!iter.IsAtEnd(); iter.Advance()) {
if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
return JSProxy::GetElementWithHandler(
Handle<JSProxy>::cast(PrototypeIterator::GetCurrent(iter)), receiver,
index);
}
// Inline the case for JSObjects. Doing so significantly improves the
// performance of fetching elements where checking the prototype chain is
// necessary.
Handle<JSObject> js_object =
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter));
// Check access rights if needed.
if (js_object->IsAccessCheckNeeded()) {
if (!isolate->MayIndexedAccess(js_object, index, v8::ACCESS_GET)) {
isolate->ReportFailedAccessCheck(js_object, v8::ACCESS_GET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->undefined_value();
}
}
if (js_object->HasIndexedInterceptor()) {
return JSObject::GetElementWithInterceptor(js_object, receiver, index);
}
if (js_object->elements() != isolate->heap()->empty_fixed_array()) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
js_object->GetElementsAccessor()->Get(receiver, js_object, index),
Object);
if (!result->IsTheHole()) return result;
}
}
return isolate->factory()->undefined_value();
}
Map* Object::GetRootMap(Isolate* isolate) {
DisallowHeapAllocation no_alloc;
if (IsSmi()) {
Context* context = isolate->context()->native_context();
return context->number_function()->initial_map();
}
HeapObject* heap_object = HeapObject::cast(this);
// The object is either a number, a string, a boolean,
// a real JS object, or a Harmony proxy.
if (heap_object->IsJSReceiver()) {
return heap_object->map();
}
Context* context = isolate->context()->native_context();
if (heap_object->IsHeapNumber()) {
return context->number_function()->initial_map();
}
if (heap_object->IsString()) {
return context->string_function()->initial_map();
}
if (heap_object->IsSymbol()) {
return context->symbol_function()->initial_map();
}
if (heap_object->IsBoolean()) {
return context->boolean_function()->initial_map();
}
return isolate->heap()->null_value()->map();
}
Object* Object::GetHash() {
// The object is either a number, a name, an odd-ball,
// a real JS object, or a Harmony proxy.
if (IsNumber()) {
uint32_t hash = ComputeLongHash(double_to_uint64(Number()));
return Smi::FromInt(hash & Smi::kMaxValue);
}
if (IsName()) {
uint32_t hash = Name::cast(this)->Hash();
return Smi::FromInt(hash);
}
if (IsOddball()) {
uint32_t hash = Oddball::cast(this)->to_string()->Hash();
return Smi::FromInt(hash);
}
DCHECK(IsJSReceiver());
return JSReceiver::cast(this)->GetIdentityHash();
}
Handle<Smi> Object::GetOrCreateHash(Isolate* isolate, Handle<Object> object) {
Handle<Object> hash(object->GetHash(), isolate);
if (hash->IsSmi()) return Handle<Smi>::cast(hash);
DCHECK(object->IsJSReceiver());
return JSReceiver::GetOrCreateIdentityHash(Handle<JSReceiver>::cast(object));
}
bool Object::SameValue(Object* other) {
if (other == this) return true;
// The object is either a number, a name, an odd-ball,
// a real JS object, or a Harmony proxy.
if (IsNumber() && other->IsNumber()) {
double this_value = Number();
double other_value = other->Number();
bool equal = this_value == other_value;
// SameValue(NaN, NaN) is true.
if (!equal) return std::isnan(this_value) && std::isnan(other_value);
// SameValue(0.0, -0.0) is false.
return (this_value != 0) || ((1 / this_value) == (1 / other_value));
}
if (IsString() && other->IsString()) {
return String::cast(this)->Equals(String::cast(other));
}
return false;
}
bool Object::SameValueZero(Object* other) {
if (other == this) return true;
// The object is either a number, a name, an odd-ball,
// a real JS object, or a Harmony proxy.
if (IsNumber() && other->IsNumber()) {
double this_value = Number();
double other_value = other->Number();
// +0 == -0 is true
return this_value == other_value
|| (std::isnan(this_value) && std::isnan(other_value));
}
if (IsString() && other->IsString()) {
return String::cast(this)->Equals(String::cast(other));
}
return false;
}
void Object::ShortPrint(FILE* out) {
OFStream os(out);
os << Brief(this);
}
void Object::ShortPrint(StringStream* accumulator) {
OStringStream os;
os << Brief(this);
accumulator->Add(os.c_str());
}
OStream& operator<<(OStream& os, const Brief& v) {
if (v.value->IsSmi()) {
Smi::cast(v.value)->SmiPrint(os);
} else {
// TODO(svenpanne) Const-correct HeapObjectShortPrint!
HeapObject* obj = const_cast<HeapObject*>(HeapObject::cast(v.value));
obj->HeapObjectShortPrint(os);
}
return os;
}
void Smi::SmiPrint(OStream& os) const { // NOLINT
os << value();
}
// Should a word be prefixed by 'a' or 'an' in order to read naturally in
// English? Returns false for non-ASCII or words that don't start with
// a capital letter. The a/an rule follows pronunciation in English.
// We don't use the BBC's overcorrect "an historic occasion" though if
// you speak a dialect you may well say "an 'istoric occasion".
static bool AnWord(String* str) {
if (str->length() == 0) return false; // A nothing.
int c0 = str->Get(0);
int c1 = str->length() > 1 ? str->Get(1) : 0;
if (c0 == 'U') {
if (c1 > 'Z') {
return true; // An Umpire, but a UTF8String, a U.
}
} else if (c0 == 'A' || c0 == 'E' || c0 == 'I' || c0 == 'O') {
return true; // An Ape, an ABCBook.
} else if ((c1 == 0 || (c1 >= 'A' && c1 <= 'Z')) &&
(c0 == 'F' || c0 == 'H' || c0 == 'M' || c0 == 'N' || c0 == 'R' ||
c0 == 'S' || c0 == 'X')) {
return true; // An MP3File, an M.
}
return false;
}
Handle<String> String::SlowFlatten(Handle<ConsString> cons,
PretenureFlag pretenure) {
DCHECK(AllowHeapAllocation::IsAllowed());
DCHECK(cons->second()->length() != 0);
Isolate* isolate = cons->GetIsolate();
int length = cons->length();
PretenureFlag tenure = isolate->heap()->InNewSpace(*cons) ? pretenure
: TENURED;
Handle<SeqString> result;
if (cons->IsOneByteRepresentation()) {
Handle<SeqOneByteString> flat = isolate->factory()->NewRawOneByteString(
length, tenure).ToHandleChecked();
DisallowHeapAllocation no_gc;
WriteToFlat(*cons, flat->GetChars(), 0, length);
result = flat;
} else {
Handle<SeqTwoByteString> flat = isolate->factory()->NewRawTwoByteString(
length, tenure).ToHandleChecked();
DisallowHeapAllocation no_gc;
WriteToFlat(*cons, flat->GetChars(), 0, length);
result = flat;
}
cons->set_first(*result);
cons->set_second(isolate->heap()->empty_string());
DCHECK(result->IsFlat());
return result;
}
bool String::MakeExternal(v8::String::ExternalStringResource* resource) {
// Externalizing twice leaks the external resource, so it's
// prohibited by the API.
DCHECK(!this->IsExternalString());
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
// Assert that the resource and the string are equivalent.
DCHECK(static_cast<size_t>(this->length()) == resource->length());
ScopedVector<uc16> smart_chars(this->length());
String::WriteToFlat(this, smart_chars.start(), 0, this->length());
DCHECK(memcmp(smart_chars.start(),
resource->data(),
resource->length() * sizeof(smart_chars[0])) == 0);
}
#endif // DEBUG
int size = this->Size(); // Byte size of the original string.
// Abort if size does not allow in-place conversion.
if (size < ExternalString::kShortSize) return false;
Heap* heap = GetHeap();
bool is_one_byte = this->IsOneByteRepresentation();
bool is_internalized = this->IsInternalizedString();
// Morph the string to an external string by replacing the map and
// reinitializing the fields. This won't work if the space the existing
// string occupies is too small for a regular external string.
// Instead, we resort to a short external string instead, omitting
// the field caching the address of the backing store. When we encounter
// short external strings in generated code, we need to bailout to runtime.
Map* new_map;
if (size < ExternalString::kSize) {
new_map = is_internalized
? (is_one_byte
? heap->short_external_internalized_string_with_one_byte_data_map()
: heap->short_external_internalized_string_map())
: (is_one_byte ? heap->short_external_string_with_one_byte_data_map()
: heap->short_external_string_map());
} else {
new_map = is_internalized
? (is_one_byte
? heap->external_internalized_string_with_one_byte_data_map()
: heap->external_internalized_string_map())
: (is_one_byte ? heap->external_string_with_one_byte_data_map()
: heap->external_string_map());
}
// Byte size of the external String object.
int new_size = this->SizeFromMap(new_map);
heap->CreateFillerObjectAt(this->address() + new_size, size - new_size);
// We are storing the new map using release store after creating a filler for
// the left-over space to avoid races with the sweeper thread.
this->synchronized_set_map(new_map);
ExternalTwoByteString* self = ExternalTwoByteString::cast(this);
self->set_resource(resource);
if (is_internalized) self->Hash(); // Force regeneration of the hash value.
heap->AdjustLiveBytes(this->address(), new_size - size, Heap::FROM_MUTATOR);
return true;
}
bool String::MakeExternal(v8::String::ExternalOneByteStringResource* resource) {
// Externalizing twice leaks the external resource, so it's
// prohibited by the API.
DCHECK(!this->IsExternalString());
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
// Assert that the resource and the string are equivalent.
DCHECK(static_cast<size_t>(this->length()) == resource->length());
if (this->IsTwoByteRepresentation()) {
ScopedVector<uint16_t> smart_chars(this->length());
String::WriteToFlat(this, smart_chars.start(), 0, this->length());
DCHECK(String::IsOneByte(smart_chars.start(), this->length()));
}
ScopedVector<char> smart_chars(this->length());
String::WriteToFlat(this, smart_chars.start(), 0, this->length());
DCHECK(memcmp(smart_chars.start(),
resource->data(),
resource->length() * sizeof(smart_chars[0])) == 0);
}
#endif // DEBUG
int size = this->Size(); // Byte size of the original string.
// Abort if size does not allow in-place conversion.
if (size < ExternalString::kShortSize) return false;
Heap* heap = GetHeap();
bool is_internalized = this->IsInternalizedString();
// Morph the string to an external string by replacing the map and
// reinitializing the fields. This won't work if the space the existing
// string occupies is too small for a regular external string.
// Instead, we resort to a short external string instead, omitting
// the field caching the address of the backing store. When we encounter
// short external strings in generated code, we need to bailout to runtime.
Map* new_map;
if (size < ExternalString::kSize) {
new_map = is_internalized
? heap->short_external_one_byte_internalized_string_map()
: heap->short_external_one_byte_string_map();
} else {
new_map = is_internalized
? heap->external_one_byte_internalized_string_map()
: heap->external_one_byte_string_map();
}
// Byte size of the external String object.
int new_size = this->SizeFromMap(new_map);
heap->CreateFillerObjectAt(this->address() + new_size, size - new_size);
// We are storing the new map using release store after creating a filler for
// the left-over space to avoid races with the sweeper thread.
this->synchronized_set_map(new_map);
ExternalOneByteString* self = ExternalOneByteString::cast(this);
self->set_resource(resource);
if (is_internalized) self->Hash(); // Force regeneration of the hash value.
heap->AdjustLiveBytes(this->address(), new_size - size, Heap::FROM_MUTATOR);
return true;
}
void String::StringShortPrint(StringStream* accumulator) {
int len = length();
if (len > kMaxShortPrintLength) {
accumulator->Add("<Very long string[%u]>", len);
return;
}
if (!LooksValid()) {
accumulator->Add("<Invalid String>");
return;
}
ConsStringIteratorOp op;
StringCharacterStream stream(this, &op);
bool truncated = false;
if (len > kMaxShortPrintLength) {
len = kMaxShortPrintLength;
truncated = true;
}
bool one_byte = true;
for (int i = 0; i < len; i++) {
uint16_t c = stream.GetNext();
if (c < 32 || c >= 127) {
one_byte = false;
}
}
stream.Reset(this);
if (one_byte) {
accumulator->Add("<String[%u]: ", length());
for (int i = 0; i < len; i++) {
accumulator->Put(static_cast<char>(stream.GetNext()));
}
accumulator->Put('>');
} else {
// Backslash indicates that the string contains control
// characters and that backslashes are therefore escaped.
accumulator->Add("<String[%u]\\: ", length());
for (int i = 0; i < len; i++) {
uint16_t c = stream.GetNext();
if (c == '\n') {
accumulator->Add("\\n");
} else if (c == '\r') {
accumulator->Add("\\r");
} else if (c == '\\') {
accumulator->Add("\\\\");
} else if (c < 32 || c > 126) {
accumulator->Add("\\x%02x", c);
} else {
accumulator->Put(static_cast<char>(c));
}
}
if (truncated) {
accumulator->Put('.');
accumulator->Put('.');
accumulator->Put('.');
}
accumulator->Put('>');
}
return;
}
void String::PrintUC16(OStream& os, int start, int end) { // NOLINT
if (end < 0) end = length();
ConsStringIteratorOp op;
StringCharacterStream stream(this, &op, start);
for (int i = start; i < end && stream.HasMore(); i++) {
os << AsUC16(stream.GetNext());
}
}
void JSObject::JSObjectShortPrint(StringStream* accumulator) {
switch (map()->instance_type()) {
case JS_ARRAY_TYPE: {
double length = JSArray::cast(this)->length()->IsUndefined()
? 0
: JSArray::cast(this)->length()->Number();
accumulator->Add("<JS Array[%u]>", static_cast<uint32_t>(length));
break;
}
case JS_WEAK_MAP_TYPE: {
accumulator->Add("<JS WeakMap>");
break;
}
case JS_WEAK_SET_TYPE: {
accumulator->Add("<JS WeakSet>");
break;
}
case JS_REGEXP_TYPE: {
accumulator->Add("<JS RegExp>");
break;
}
case JS_FUNCTION_TYPE: {
JSFunction* function = JSFunction::cast(this);
Object* fun_name = function->shared()->DebugName();
bool printed = false;
if (fun_name->IsString()) {
String* str = String::cast(fun_name);
if (str->length() > 0) {
accumulator->Add("<JS Function ");
accumulator->Put(str);
printed = true;
}
}
if (!printed) {
accumulator->Add("<JS Function");
}
accumulator->Add(" (SharedFunctionInfo %p)",
reinterpret_cast<void*>(function->shared()));
accumulator->Put('>');
break;
}
case JS_GENERATOR_OBJECT_TYPE: {
accumulator->Add("<JS Generator>");
break;
}
case JS_MODULE_TYPE: {
accumulator->Add("<JS Module>");
break;
}
// All other JSObjects are rather similar to each other (JSObject,
// JSGlobalProxy, JSGlobalObject, JSUndetectableObject, JSValue).
default: {
Map* map_of_this = map();
Heap* heap = GetHeap();
Object* constructor = map_of_this->constructor();
bool printed = false;
if (constructor->IsHeapObject() &&
!heap->Contains(HeapObject::cast(constructor))) {
accumulator->Add("!!!INVALID CONSTRUCTOR!!!");
} else {
bool global_object = IsJSGlobalProxy();
if (constructor->IsJSFunction()) {
if (!heap->Contains(JSFunction::cast(constructor)->shared())) {
accumulator->Add("!!!INVALID SHARED ON CONSTRUCTOR!!!");
} else {
Object* constructor_name =
JSFunction::cast(constructor)->shared()->name();
if (constructor_name->IsString()) {
String* str = String::cast(constructor_name);
if (str->length() > 0) {
bool vowel = AnWord(str);
accumulator->Add("<%sa%s ",
global_object ? "Global Object: " : "",
vowel ? "n" : "");
accumulator->Put(str);
accumulator->Add(" with %smap %p",
map_of_this->is_deprecated() ? "deprecated " : "",
map_of_this);
printed = true;
}
}
}
}
if (!printed) {
accumulator->Add("<JS %sObject", global_object ? "Global " : "");
}
}
if (IsJSValue()) {
accumulator->Add(" value = ");
JSValue::cast(this)->value()->ShortPrint(accumulator);
}
accumulator->Put('>');
break;
}
}
}
void JSObject::PrintElementsTransition(
FILE* file, Handle<JSObject> object,
ElementsKind from_kind, Handle<FixedArrayBase> from_elements,
ElementsKind to_kind, Handle<FixedArrayBase> to_elements) {
if (from_kind != to_kind) {
OFStream os(file);
os << "elements transition [" << ElementsKindToString(from_kind) << " -> "
<< ElementsKindToString(to_kind) << "] in ";
JavaScriptFrame::PrintTop(object->GetIsolate(), file, false, true);
PrintF(file, " for ");
object->ShortPrint(file);
PrintF(file, " from ");
from_elements->ShortPrint(file);
PrintF(file, " to ");
to_elements->ShortPrint(file);
PrintF(file, "\n");
}
}
void Map::PrintGeneralization(FILE* file,
const char* reason,
int modify_index,
int split,
int descriptors,
bool constant_to_field,
Representation old_representation,
Representation new_representation,
HeapType* old_field_type,
HeapType* new_field_type) {
OFStream os(file);
os << "[generalizing ";
constructor_name()->PrintOn(file);
os << "] ";
Name* name = instance_descriptors()->GetKey(modify_index);
if (name->IsString()) {
String::cast(name)->PrintOn(file);
} else {
os << "{symbol " << static_cast<void*>(name) << "}";
}
os << ":";
if (constant_to_field) {
os << "c";
} else {
os << old_representation.Mnemonic() << "{";
old_field_type->PrintTo(os, HeapType::SEMANTIC_DIM);
os << "}";
}
os << "->" << new_representation.Mnemonic() << "{";
new_field_type->PrintTo(os, HeapType::SEMANTIC_DIM);
os << "} (";
if (strlen(reason) > 0) {
os << reason;
} else {
os << "+" << (descriptors - split) << " maps";
}
os << ") [";
JavaScriptFrame::PrintTop(GetIsolate(), file, false, true);
os << "]\n";
}
void JSObject::PrintInstanceMigration(FILE* file,
Map* original_map,
Map* new_map) {
PrintF(file, "[migrating ");
map()->constructor_name()->PrintOn(file);
PrintF(file, "] ");
DescriptorArray* o = original_map->instance_descriptors();
DescriptorArray* n = new_map->instance_descriptors();
for (int i = 0; i < original_map->NumberOfOwnDescriptors(); i++) {
Representation o_r = o->GetDetails(i).representation();
Representation n_r = n->GetDetails(i).representation();
if (!o_r.Equals(n_r)) {
String::cast(o->GetKey(i))->PrintOn(file);
PrintF(file, ":%s->%s ", o_r.Mnemonic(), n_r.Mnemonic());
} else if (o->GetDetails(i).type() == CONSTANT &&
n->GetDetails(i).type() == FIELD) {
Name* name = o->GetKey(i);
if (name->IsString()) {
String::cast(name)->PrintOn(file);
} else {
PrintF(file, "{symbol %p}", static_cast<void*>(name));
}
PrintF(file, " ");
}
}
PrintF(file, "\n");
}
void HeapObject::HeapObjectShortPrint(OStream& os) { // NOLINT
Heap* heap = GetHeap();
if (!heap->Contains(this)) {
os << "!!!INVALID POINTER!!!";
return;
}
if (!heap->Contains(map())) {
os << "!!!INVALID MAP!!!";
return;
}
os << this << " ";
if (IsString()) {
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
String::cast(this)->StringShortPrint(&accumulator);
os << accumulator.ToCString().get();
return;
}
if (IsJSObject()) {
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
JSObject::cast(this)->JSObjectShortPrint(&accumulator);
os << accumulator.ToCString().get();
return;
}
switch (map()->instance_type()) {
case MAP_TYPE:
os << "<Map(elements=" << Map::cast(this)->elements_kind() << ")>";
break;
case FIXED_ARRAY_TYPE:
os << "<FixedArray[" << FixedArray::cast(this)->length() << "]>";
break;
case FIXED_DOUBLE_ARRAY_TYPE:
os << "<FixedDoubleArray[" << FixedDoubleArray::cast(this)->length()
<< "]>";
break;
case BYTE_ARRAY_TYPE:
os << "<ByteArray[" << ByteArray::cast(this)->length() << "]>";
break;
case FREE_SPACE_TYPE:
os << "<FreeSpace[" << FreeSpace::cast(this)->Size() << "]>";
break;
#define TYPED_ARRAY_SHORT_PRINT(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ARRAY_TYPE: \
os << "<External" #Type "Array[" \
<< External##Type##Array::cast(this)->length() << "]>"; \
break; \
case FIXED_##TYPE##_ARRAY_TYPE: \
os << "<Fixed" #Type "Array[" << Fixed##Type##Array::cast(this)->length() \
<< "]>"; \
break;
TYPED_ARRAYS(TYPED_ARRAY_SHORT_PRINT)
#undef TYPED_ARRAY_SHORT_PRINT
case SHARED_FUNCTION_INFO_TYPE: {
SharedFunctionInfo* shared = SharedFunctionInfo::cast(this);
SmartArrayPointer<char> debug_name =
shared->DebugName()->ToCString();
if (debug_name[0] != 0) {
os << "<SharedFunctionInfo " << debug_name.get() << ">";
} else {
os << "<SharedFunctionInfo>";
}
break;
}
case JS_MESSAGE_OBJECT_TYPE:
os << "<JSMessageObject>";
break;
#define MAKE_STRUCT_CASE(NAME, Name, name) \
case NAME##_TYPE: \
os << "<" #Name ">"; \
break;
STRUCT_LIST(MAKE_STRUCT_CASE)
#undef MAKE_STRUCT_CASE
case CODE_TYPE: {
Code* code = Code::cast(this);
os << "<Code: " << Code::Kind2String(code->kind()) << ">";
break;
}
case ODDBALL_TYPE: {
if (IsUndefined()) {
os << "<undefined>";
} else if (IsTheHole()) {
os << "<the hole>";
} else if (IsNull()) {
os << "<null>";
} else if (IsTrue()) {
os << "<true>";
} else if (IsFalse()) {
os << "<false>";
} else {
os << "<Odd Oddball>";
}
break;
}
case SYMBOL_TYPE: {
Symbol* symbol = Symbol::cast(this);
os << "<Symbol: " << symbol->Hash();
if (!symbol->name()->IsUndefined()) {
os << " ";
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
String::cast(symbol->name())->StringShortPrint(&accumulator);
os << accumulator.ToCString().get();
}
os << ">";
break;
}
case HEAP_NUMBER_TYPE: {
os << "<Number: ";
HeapNumber::cast(this)->HeapNumberPrint(os);
os << ">";
break;
}
case MUTABLE_HEAP_NUMBER_TYPE: {
os << "<MutableNumber: ";
HeapNumber::cast(this)->HeapNumberPrint(os);
os << '>';
break;
}
case JS_PROXY_TYPE:
os << "<JSProxy>";
break;
case JS_FUNCTION_PROXY_TYPE:
os << "<JSFunctionProxy>";
break;
case FOREIGN_TYPE:
os << "<Foreign>";
break;
case CELL_TYPE: {
os << "Cell for ";
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
Cell::cast(this)->value()->ShortPrint(&accumulator);
os << accumulator.ToCString().get();
break;
}
case PROPERTY_CELL_TYPE: {
os << "PropertyCell for ";
HeapStringAllocator allocator;
StringStream accumulator(&allocator);
PropertyCell::cast(this)->value()->ShortPrint(&accumulator);
os << accumulator.ToCString().get();
break;
}
default:
os << "<Other heap object (" << map()->instance_type() << ")>";
break;
}
}
void HeapObject::Iterate(ObjectVisitor* v) {
// Handle header
IteratePointer(v, kMapOffset);
// Handle object body
Map* m = map();
IterateBody(m->instance_type(), SizeFromMap(m), v);
}
void HeapObject::IterateBody(InstanceType type, int object_size,
ObjectVisitor* v) {
// Avoiding <Type>::cast(this) because it accesses the map pointer field.
// During GC, the map pointer field is encoded.
if (type < FIRST_NONSTRING_TYPE) {
switch (type & kStringRepresentationMask) {
case kSeqStringTag:
break;
case kConsStringTag:
ConsString::BodyDescriptor::IterateBody(this, v);
break;
case kSlicedStringTag:
SlicedString::BodyDescriptor::IterateBody(this, v);
break;
case kExternalStringTag:
if ((type & kStringEncodingMask) == kOneByteStringTag) {
reinterpret_cast<ExternalOneByteString*>(this)
->ExternalOneByteStringIterateBody(v);
} else {
reinterpret_cast<ExternalTwoByteString*>(this)->
ExternalTwoByteStringIterateBody(v);
}
break;
}
return;
}
switch (type) {
case FIXED_ARRAY_TYPE:
FixedArray::BodyDescriptor::IterateBody(this, object_size, v);
break;
case CONSTANT_POOL_ARRAY_TYPE:
reinterpret_cast<ConstantPoolArray*>(this)->ConstantPoolIterateBody(v);
break;
case FIXED_DOUBLE_ARRAY_TYPE:
break;
case JS_OBJECT_TYPE:
case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
case JS_GENERATOR_OBJECT_TYPE:
case JS_MODULE_TYPE:
case JS_VALUE_TYPE:
case JS_DATE_TYPE:
case JS_ARRAY_TYPE:
case JS_ARRAY_BUFFER_TYPE:
case JS_TYPED_ARRAY_TYPE:
case JS_DATA_VIEW_TYPE:
case JS_SET_TYPE:
case JS_MAP_TYPE:
case JS_SET_ITERATOR_TYPE:
case JS_MAP_ITERATOR_TYPE:
case JS_WEAK_MAP_TYPE:
case JS_WEAK_SET_TYPE:
case JS_REGEXP_TYPE:
case JS_GLOBAL_PROXY_TYPE:
case JS_GLOBAL_OBJECT_TYPE:
case JS_BUILTINS_OBJECT_TYPE:
case JS_MESSAGE_OBJECT_TYPE:
JSObject::BodyDescriptor::IterateBody(this, object_size, v);
break;
case JS_FUNCTION_TYPE:
reinterpret_cast<JSFunction*>(this)
->JSFunctionIterateBody(object_size, v);
break;
case ODDBALL_TYPE:
Oddball::BodyDescriptor::IterateBody(this, v);
break;
case JS_PROXY_TYPE:
JSProxy::BodyDescriptor::IterateBody(this, v);
break;
case JS_FUNCTION_PROXY_TYPE:
JSFunctionProxy::BodyDescriptor::IterateBody(this, v);
break;
case FOREIGN_TYPE:
reinterpret_cast<Foreign*>(this)->ForeignIterateBody(v);
break;
case MAP_TYPE:
Map::BodyDescriptor::IterateBody(this, v);
break;
case CODE_TYPE:
reinterpret_cast<Code*>(this)->CodeIterateBody(v);
break;
case CELL_TYPE:
Cell::BodyDescriptor::IterateBody(this, v);
break;
case PROPERTY_CELL_TYPE:
PropertyCell::BodyDescriptor::IterateBody(this, v);
break;
case SYMBOL_TYPE:
Symbol::BodyDescriptor::IterateBody(this, v);
break;
case HEAP_NUMBER_TYPE:
case MUTABLE_HEAP_NUMBER_TYPE:
case FILLER_TYPE:
case BYTE_ARRAY_TYPE:
case FREE_SPACE_TYPE:
break;
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ARRAY_TYPE: \
case FIXED_##TYPE##_ARRAY_TYPE: \
break;
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
case SHARED_FUNCTION_INFO_TYPE: {
SharedFunctionInfo::BodyDescriptor::IterateBody(this, v);
break;
}
#define MAKE_STRUCT_CASE(NAME, Name, name) \
case NAME##_TYPE:
STRUCT_LIST(MAKE_STRUCT_CASE)
#undef MAKE_STRUCT_CASE
if (type == ALLOCATION_SITE_TYPE) {
AllocationSite::BodyDescriptor::IterateBody(this, v);
} else {
StructBodyDescriptor::IterateBody(this, object_size, v);
}
break;
default:
PrintF("Unknown type: %d\n", type);
UNREACHABLE();
}
}
bool HeapNumber::HeapNumberBooleanValue() {
return DoubleToBoolean(value());
}
void HeapNumber::HeapNumberPrint(OStream& os) { // NOLINT
os << value();
}
String* JSReceiver::class_name() {
if (IsJSFunction() || IsJSFunctionProxy()) {
return GetHeap()->Function_string();
}
if (map()->constructor()->IsJSFunction()) {
JSFunction* constructor = JSFunction::cast(map()->constructor());
return String::cast(constructor->shared()->instance_class_name());
}
// If the constructor is not present, return "Object".
return GetHeap()->Object_string();
}
String* Map::constructor_name() {
if (constructor()->IsJSFunction()) {
JSFunction* constructor = JSFunction::cast(this->constructor());
String* name = String::cast(constructor->shared()->name());
if (name->length() > 0) return name;
String* inferred_name = constructor->shared()->inferred_name();
if (inferred_name->length() > 0) return inferred_name;
Object* proto = prototype();
if (proto->IsJSObject()) return JSObject::cast(proto)->constructor_name();
}
// TODO(rossberg): what about proxies?
// If the constructor is not present, return "Object".
return GetHeap()->Object_string();
}
String* JSReceiver::constructor_name() {
return map()->constructor_name();
}
MaybeHandle<Map> Map::CopyWithField(Handle<Map> map,
Handle<Name> name,
Handle<HeapType> type,
PropertyAttributes attributes,
Representation representation,
TransitionFlag flag) {
DCHECK(DescriptorArray::kNotFound ==
map->instance_descriptors()->Search(
*name, map->NumberOfOwnDescriptors()));
// Ensure the descriptor array does not get too big.
if (map->NumberOfOwnDescriptors() >= kMaxNumberOfDescriptors) {
return MaybeHandle<Map>();
}
Isolate* isolate = map->GetIsolate();
// Compute the new index for new field.
int index = map->NextFreePropertyIndex();
if (map->instance_type() == JS_CONTEXT_EXTENSION_OBJECT_TYPE) {
representation = Representation::Tagged();
type = HeapType::Any(isolate);
}
FieldDescriptor new_field_desc(name, index, type, attributes, representation);
Handle<Map> new_map = Map::CopyAddDescriptor(map, &new_field_desc, flag);
int unused_property_fields = new_map->unused_property_fields() - 1;
if (unused_property_fields < 0) {
unused_property_fields += JSObject::kFieldsAdded;
}
new_map->set_unused_property_fields(unused_property_fields);
return new_map;
}
MaybeHandle<Map> Map::CopyWithConstant(Handle<Map> map,
Handle<Name> name,
Handle<Object> constant,
PropertyAttributes attributes,
TransitionFlag flag) {
// Ensure the descriptor array does not get too big.
if (map->NumberOfOwnDescriptors() >= kMaxNumberOfDescriptors) {
return MaybeHandle<Map>();
}
// Allocate new instance descriptors with (name, constant) added.
ConstantDescriptor new_constant_desc(name, constant, attributes);
return Map::CopyAddDescriptor(map, &new_constant_desc, flag);
}
void JSObject::AddSlowProperty(Handle<JSObject> object,
Handle<Name> name,
Handle<Object> value,
PropertyAttributes attributes) {
DCHECK(!object->HasFastProperties());
Isolate* isolate = object->GetIsolate();
Handle<NameDictionary> dict(object->property_dictionary());
if (object->IsGlobalObject()) {
// In case name is an orphaned property reuse the cell.
int entry = dict->FindEntry(name);
if (entry != NameDictionary::kNotFound) {
Handle<PropertyCell> cell(PropertyCell::cast(dict->ValueAt(entry)));
PropertyCell::SetValueInferType(cell, value);
// Assign an enumeration index to the property and update
// SetNextEnumerationIndex.
int index = dict->NextEnumerationIndex();
PropertyDetails details = PropertyDetails(attributes, NORMAL, index);
dict->SetNextEnumerationIndex(index + 1);
dict->SetEntry(entry, name, cell, details);
return;
}
Handle<PropertyCell> cell = isolate->factory()->NewPropertyCell(value);
PropertyCell::SetValueInferType(cell, value);
value = cell;
}
PropertyDetails details = PropertyDetails(attributes, NORMAL, 0);
Handle<NameDictionary> result =
NameDictionary::Add(dict, name, value, details);
if (*dict != *result) object->set_properties(*result);
}
Context* JSObject::GetCreationContext() {
Object* constructor = this->map()->constructor();
JSFunction* function;
if (!constructor->IsJSFunction()) {
// Functions have null as a constructor,
// but any JSFunction knows its context immediately.
function = JSFunction::cast(this);
} else {
function = JSFunction::cast(constructor);
}
return function->context()->native_context();
}
void JSObject::EnqueueChangeRecord(Handle<JSObject> object,
const char* type_str,
Handle<Name> name,
Handle<Object> old_value) {
DCHECK(!object->IsJSGlobalProxy());
DCHECK(!object->IsJSGlobalObject());
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
Handle<String> type = isolate->factory()->InternalizeUtf8String(type_str);
Handle<Object> args[] = { type, object, name, old_value };
int argc = name.is_null() ? 2 : old_value->IsTheHole() ? 3 : 4;
Execution::Call(isolate,
Handle<JSFunction>(isolate->observers_notify_change()),
isolate->factory()->undefined_value(),
argc, args).Assert();
}
const char* Representation::Mnemonic() const {
switch (kind_) {
case kNone: return "v";
case kTagged: return "t";
case kSmi: return "s";
case kDouble: return "d";
case kInteger32: return "i";
case kHeapObject: return "h";
case kExternal: return "x";
default:
UNREACHABLE();
return NULL;
}
}
bool Map::InstancesNeedRewriting(Map* target, int target_number_of_fields,
int target_inobject, int target_unused,
int* old_number_of_fields) {
// If fields were added (or removed), rewrite the instance.
*old_number_of_fields = NumberOfFields();
DCHECK(target_number_of_fields >= *old_number_of_fields);
if (target_number_of_fields != *old_number_of_fields) return true;
// If smi descriptors were replaced by double descriptors, rewrite.
DescriptorArray* old_desc = instance_descriptors();
DescriptorArray* new_desc = target->instance_descriptors();
int limit = NumberOfOwnDescriptors();
for (int i = 0; i < limit; i++) {
if (new_desc->GetDetails(i).representation().IsDouble() !=
old_desc->GetDetails(i).representation().IsDouble()) {
return true;
}
}
// If no fields were added, and no inobject properties were removed, setting
// the map is sufficient.
if (target_inobject == inobject_properties()) return false;
// In-object slack tracking may have reduced the object size of the new map.
// In that case, succeed if all existing fields were inobject, and they still
// fit within the new inobject size.
DCHECK(target_inobject < inobject_properties());
if (target_number_of_fields <= target_inobject) {
DCHECK(target_number_of_fields + target_unused == target_inobject);
return false;
}
// Otherwise, properties will need to be moved to the backing store.
return true;
}
void Map::ConnectElementsTransition(Handle<Map> parent, Handle<Map> child) {
Isolate* isolate = parent->GetIsolate();
Handle<Name> name = isolate->factory()->elements_transition_symbol();
ConnectTransition(parent, child, name, FULL_TRANSITION);
}
void JSObject::MigrateToMap(Handle<JSObject> object, Handle<Map> new_map) {
if (object->map() == *new_map) return;
if (object->HasFastProperties()) {
if (!new_map->is_dictionary_map()) {
Handle<Map> old_map(object->map());
MigrateFastToFast(object, new_map);
if (old_map->is_prototype_map()) {
// Clear out the old descriptor array to avoid problems to sharing
// the descriptor array without using an explicit.
old_map->InitializeDescriptors(
old_map->GetHeap()->empty_descriptor_array());
// Ensure that no transition was inserted for prototype migrations.
DCHECK(!old_map->HasTransitionArray());
DCHECK(new_map->GetBackPointer()->IsUndefined());
}
} else {
MigrateFastToSlow(object, new_map, 0);
}
} else {
// For slow-to-fast migrations JSObject::TransformToFastProperties()
// must be used instead.
CHECK(new_map->is_dictionary_map());
// Slow-to-slow migration is trivial.
object->set_map(*new_map);
}
}
// To migrate a fast instance to a fast map:
// - First check whether the instance needs to be rewritten. If not, simply
// change the map.
// - Otherwise, allocate a fixed array large enough to hold all fields, in
// addition to unused space.
// - Copy all existing properties in, in the following order: backing store
// properties, unused fields, inobject properties.
// - If all allocation succeeded, commit the state atomically:
// * Copy inobject properties from the backing store back into the object.
// * Trim the difference in instance size of the object. This also cleanly
// frees inobject properties that moved to the backing store.
// * If there are properties left in the backing store, trim of the space used
// to temporarily store the inobject properties.
// * If there are properties left in the backing store, install the backing
// store.
void JSObject::MigrateFastToFast(Handle<JSObject> object, Handle<Map> new_map) {
Isolate* isolate = object->GetIsolate();
Handle<Map> old_map(object->map());
int old_number_of_fields;
int number_of_fields = new_map->NumberOfFields();
int inobject = new_map->inobject_properties();
int unused = new_map->unused_property_fields();
// Nothing to do if no functions were converted to fields and no smis were
// converted to doubles.
if (!old_map->InstancesNeedRewriting(*new_map, number_of_fields, inobject,
unused, &old_number_of_fields)) {
object->synchronized_set_map(*new_map);
return;
}
int total_size = number_of_fields + unused;
int external = total_size - inobject;
if (number_of_fields != old_number_of_fields &&
new_map->GetBackPointer() == *old_map) {
PropertyDetails details = new_map->GetLastDescriptorDetails();
if (old_map->unused_property_fields() > 0) {
if (details.representation().IsDouble()) {
Handle<Object> value = isolate->factory()->NewHeapNumber(0, MUTABLE);
FieldIndex index =
FieldIndex::ForDescriptor(*new_map, new_map->LastAdded());
object->FastPropertyAtPut(index, *value);
}
object->synchronized_set_map(*new_map);
return;
}
DCHECK(number_of_fields == old_number_of_fields + 1);
// This migration is a transition from a map that has run out out property
// space. Therefore it could be done by extending the backing store.
Handle<FixedArray> old_storage = handle(object->properties(), isolate);
Handle<FixedArray> new_storage =
FixedArray::CopySize(old_storage, external);
// Properly initialize newly added property.
Handle<Object> value;
if (details.representation().IsDouble()) {
value = isolate->factory()->NewHeapNumber(0, MUTABLE);
} else {
value = isolate->factory()->uninitialized_value();
}
DCHECK(details.type() == FIELD);
int target_index = details.field_index() - inobject;
DCHECK(target_index >= 0); // Must be a backing store index.
new_storage->set(target_index, *value);
// From here on we cannot fail and we shouldn't GC anymore.
DisallowHeapAllocation no_allocation;
// Set the new property value and do the map transition.
object->set_properties(*new_storage);
object->synchronized_set_map(*new_map);
return;
}
Handle<FixedArray> array = isolate->factory()->NewFixedArray(total_size);
Handle<DescriptorArray> old_descriptors(old_map->instance_descriptors());
Handle<DescriptorArray> new_descriptors(new_map->instance_descriptors());
int old_nof = old_map->NumberOfOwnDescriptors();
int new_nof = new_map->NumberOfOwnDescriptors();
// This method only supports generalizing instances to at least the same
// number of properties.
DCHECK(old_nof <= new_nof);
for (int i = 0; i < old_nof; i++) {
PropertyDetails details = new_descriptors->GetDetails(i);
if (details.type() != FIELD) continue;
PropertyDetails old_details = old_descriptors->GetDetails(i);
if (old_details.type() == CALLBACKS) {
DCHECK(details.representation().IsTagged());
continue;
}
DCHECK(old_details.type() == CONSTANT ||
old_details.type() == FIELD);
Object* raw_value = old_details.type() == CONSTANT
? old_descriptors->GetValue(i)
: object->RawFastPropertyAt(FieldIndex::ForDescriptor(*old_map, i));
Handle<Object> value(raw_value, isolate);
if (!old_details.representation().IsDouble() &&
details.representation().IsDouble()) {
if (old_details.representation().IsNone()) {
value = handle(Smi::FromInt(0), isolate);
}
value = Object::NewStorageFor(isolate, value, details.representation());
} else if (old_details.representation().IsDouble() &&
!details.representation().IsDouble()) {
value = Object::WrapForRead(isolate, value, old_details.representation());
}
DCHECK(!(details.representation().IsDouble() && value->IsSmi()));
int target_index = new_descriptors->GetFieldIndex(i) - inobject;
if (target_index < 0) target_index += total_size;
array->set(target_index, *value);
}
for (int i = old_nof; i < new_nof; i++) {
PropertyDetails details = new_descriptors->GetDetails(i);
if (details.type() != FIELD) continue;
Handle<Object> value;
if (details.representation().IsDouble()) {
value = isolate->factory()->NewHeapNumber(0, MUTABLE);
} else {
value = isolate->factory()->uninitialized_value();
}
int target_index = new_descriptors->GetFieldIndex(i) - inobject;
if (target_index < 0) target_index += total_size;
array->set(target_index, *value);
}
// From here on we cannot fail and we shouldn't GC anymore.
DisallowHeapAllocation no_allocation;
// Copy (real) inobject properties. If necessary, stop at number_of_fields to
// avoid overwriting |one_pointer_filler_map|.
int limit = Min(inobject, number_of_fields);
for (int i = 0; i < limit; i++) {
FieldIndex index = FieldIndex::ForPropertyIndex(*new_map, i);
object->FastPropertyAtPut(index, array->get(external + i));
}
Heap* heap = isolate->heap();
// If there are properties in the new backing store, trim it to the correct
// size and install the backing store into the object.
if (external > 0) {
heap->RightTrimFixedArray<Heap::FROM_MUTATOR>(*array, inobject);
object->set_properties(*array);
}
// Create filler object past the new instance size.
int new_instance_size = new_map->instance_size();
int instance_size_delta = old_map->instance_size() - new_instance_size;
DCHECK(instance_size_delta >= 0);
if (instance_size_delta > 0) {
Address address = object->address();
heap->CreateFillerObjectAt(
address + new_instance_size, instance_size_delta);
heap->AdjustLiveBytes(address, -instance_size_delta, Heap::FROM_MUTATOR);
}
// We are storing the new map using release store after creating a filler for
// the left-over space to avoid races with the sweeper thread.
object->synchronized_set_map(*new_map);
}
void JSObject::GeneralizeFieldRepresentation(Handle<JSObject> object,
int modify_index,
Representation new_representation,
Handle<HeapType> new_field_type) {
Handle<Map> new_map = Map::GeneralizeRepresentation(
handle(object->map()), modify_index, new_representation, new_field_type,
FORCE_FIELD);
MigrateToMap(object, new_map);
}
int Map::NumberOfFields() {
DescriptorArray* descriptors = instance_descriptors();
int result = 0;
for (int i = 0; i < NumberOfOwnDescriptors(); i++) {
if (descriptors->GetDetails(i).type() == FIELD) result++;
}
return result;
}
Handle<Map> Map::CopyGeneralizeAllRepresentations(Handle<Map> map,
int modify_index,
StoreMode store_mode,
PropertyAttributes attributes,
const char* reason) {
Isolate* isolate = map->GetIsolate();
Handle<Map> new_map = Copy(map);
DescriptorArray* descriptors = new_map->instance_descriptors();
int length = descriptors->number_of_descriptors();
for (int i = 0; i < length; i++) {
descriptors->SetRepresentation(i, Representation::Tagged());
if (descriptors->GetDetails(i).type() == FIELD) {
descriptors->SetValue(i, HeapType::Any());
}
}
// Unless the instance is being migrated, ensure that modify_index is a field.
PropertyDetails details = descriptors->GetDetails(modify_index);
if (store_mode == FORCE_FIELD &&
(details.type() != FIELD || details.attributes() != attributes)) {
int field_index = details.type() == FIELD ? details.field_index()
: new_map->NumberOfFields();
FieldDescriptor d(handle(descriptors->GetKey(modify_index), isolate),
field_index, attributes, Representation::Tagged());
descriptors->Replace(modify_index, &d);
if (details.type() != FIELD) {
int unused_property_fields = new_map->unused_property_fields() - 1;
if (unused_property_fields < 0) {
unused_property_fields += JSObject::kFieldsAdded;
}
new_map->set_unused_property_fields(unused_property_fields);
}
} else {
DCHECK(details.attributes() == attributes);
}
if (FLAG_trace_generalization) {
HeapType* field_type = (details.type() == FIELD)
? map->instance_descriptors()->GetFieldType(modify_index)
: NULL;
map->PrintGeneralization(stdout, reason, modify_index,
new_map->NumberOfOwnDescriptors(),
new_map->NumberOfOwnDescriptors(),
details.type() == CONSTANT && store_mode == FORCE_FIELD,
details.representation(), Representation::Tagged(),
field_type, HeapType::Any());
}
return new_map;
}
// static
Handle<Map> Map::CopyGeneralizeAllRepresentations(Handle<Map> map,
int modify_index,
StoreMode store_mode,
const char* reason) {
PropertyDetails details =
map->instance_descriptors()->GetDetails(modify_index);
return CopyGeneralizeAllRepresentations(map, modify_index, store_mode,
details.attributes(), reason);
}
void Map::DeprecateTransitionTree() {
if (is_deprecated()) return;
if (HasTransitionArray()) {
TransitionArray* transitions = this->transitions();
for (int i = 0; i < transitions->number_of_transitions(); i++) {
transitions->GetTarget(i)->DeprecateTransitionTree();
}
}
deprecate();
dependent_code()->DeoptimizeDependentCodeGroup(
GetIsolate(), DependentCode::kTransitionGroup);
NotifyLeafMapLayoutChange();
}
// Invalidates a transition target at |key|, and installs |new_descriptors| over
// the current instance_descriptors to ensure proper sharing of descriptor
// arrays.
void Map::DeprecateTarget(Name* key, DescriptorArray* new_descriptors) {
if (HasTransitionArray()) {
TransitionArray* transitions = this->transitions();
int transition = transitions->Search(key);
if (transition != TransitionArray::kNotFound) {
transitions->GetTarget(transition)->DeprecateTransitionTree();
}
}
// Don't overwrite the empty descriptor array.
if (NumberOfOwnDescriptors() == 0) return;
DescriptorArray* to_replace = instance_descriptors();
Map* current = this;
GetHeap()->incremental_marking()->RecordWrites(to_replace);
while (current->instance_descriptors() == to_replace) {
current->SetEnumLength(kInvalidEnumCacheSentinel);
current->set_instance_descriptors(new_descriptors);
Object* next = current->GetBackPointer();
if (next->IsUndefined()) break;
current = Map::cast(next);
}
set_owns_descriptors(false);
}
Map* Map::FindRootMap() {
Map* result = this;
while (true) {
Object* back = result->GetBackPointer();
if (back->IsUndefined()) return result;
result = Map::cast(back);
}
}
Map* Map::FindLastMatchMap(int verbatim,
int length,
DescriptorArray* descriptors) {
DisallowHeapAllocation no_allocation;
// This can only be called on roots of transition trees.
DCHECK(GetBackPointer()->IsUndefined());
Map* current = this;
for (int i = verbatim; i < length; i++) {
if (!current->HasTransitionArray()) break;
Name* name = descriptors->GetKey(i);
TransitionArray* transitions = current->transitions();
int transition = transitions->Search(name);
if (transition == TransitionArray::kNotFound) break;
Map* next = transitions->GetTarget(transition);
DescriptorArray* next_descriptors = next->instance_descriptors();
PropertyDetails details = descriptors->GetDetails(i);
PropertyDetails next_details = next_descriptors->GetDetails(i);
if (details.type() != next_details.type()) break;
if (details.attributes() != next_details.attributes()) break;
if (!details.representation().Equals(next_details.representation())) break;
if (next_details.type() == FIELD) {
if (!descriptors->GetFieldType(i)->NowIs(
next_descriptors->GetFieldType(i))) break;
} else {
if (descriptors->GetValue(i) != next_descriptors->GetValue(i)) break;
}
current = next;
}
return current;
}
Map* Map::FindFieldOwner(int descriptor) {
DisallowHeapAllocation no_allocation;
DCHECK_EQ(FIELD, instance_descriptors()->GetDetails(descriptor).type());
Map* result = this;
while (true) {
Object* back = result->GetBackPointer();
if (back->IsUndefined()) break;
Map* parent = Map::cast(back);
if (parent->NumberOfOwnDescriptors() <= descriptor) break;
result = parent;
}
return result;
}
void Map::UpdateFieldType(int descriptor, Handle<Name> name,
Handle<HeapType> new_type) {
DisallowHeapAllocation no_allocation;
PropertyDetails details = instance_descriptors()->GetDetails(descriptor);
if (details.type() != FIELD) return;
if (HasTransitionArray()) {
TransitionArray* transitions = this->transitions();
for (int i = 0; i < transitions->number_of_transitions(); ++i) {
transitions->GetTarget(i)->UpdateFieldType(descriptor, name, new_type);
}
}
// Skip if already updated the shared descriptor.
if (instance_descriptors()->GetFieldType(descriptor) == *new_type) return;
FieldDescriptor d(name, instance_descriptors()->GetFieldIndex(descriptor),
new_type, details.attributes(), details.representation());
instance_descriptors()->Replace(descriptor, &d);
}
// static
Handle<HeapType> Map::GeneralizeFieldType(Handle<HeapType> type1,
Handle<HeapType> type2,
Isolate* isolate) {
static const int kMaxClassesPerFieldType = 5;
if (type1->NowIs(type2)) return type2;
if (type2->NowIs(type1)) return type1;
if (type1->NowStable() && type2->NowStable()) {
Handle<HeapType> type = HeapType::Union(type1, type2, isolate);
if (type->NumClasses() <= kMaxClassesPerFieldType) {
DCHECK(type->NowStable());
DCHECK(type1->NowIs(type));
DCHECK(type2->NowIs(type));
return type;
}
}
return HeapType::Any(isolate);
}
// static
void Map::GeneralizeFieldType(Handle<Map> map,
int modify_index,
Handle<HeapType> new_field_type) {
Isolate* isolate = map->GetIsolate();
// Check if we actually need to generalize the field type at all.
Handle<HeapType> old_field_type(
map->instance_descriptors()->GetFieldType(modify_index), isolate);
if (new_field_type->NowIs(old_field_type)) {
DCHECK(Map::GeneralizeFieldType(old_field_type,
new_field_type,
isolate)->NowIs(old_field_type));
return;
}
// Determine the field owner.
Handle<Map> field_owner(map->FindFieldOwner(modify_index), isolate);
Handle<DescriptorArray> descriptors(
field_owner->instance_descriptors(), isolate);
DCHECK_EQ(*old_field_type, descriptors->GetFieldType(modify_index));
// Determine the generalized new field type.
new_field_type = Map::GeneralizeFieldType(
old_field_type, new_field_type, isolate);
PropertyDetails details = descriptors->GetDetails(modify_index);
Handle<Name> name(descriptors->GetKey(modify_index));
field_owner->UpdateFieldType(modify_index, name, new_field_type);
field_owner->dependent_code()->DeoptimizeDependentCodeGroup(
isolate, DependentCode::kFieldTypeGroup);
if (FLAG_trace_generalization) {
map->PrintGeneralization(
stdout, "field type generalization",
modify_index, map->NumberOfOwnDescriptors(),
map->NumberOfOwnDescriptors(), false,
details.representation(), details.representation(),
*old_field_type, *new_field_type);
}
}
// Generalize the representation of the descriptor at |modify_index|.
// This method rewrites the transition tree to reflect the new change. To avoid
// high degrees over polymorphism, and to stabilize quickly, on every rewrite
// the new type is deduced by merging the current type with any potential new
// (partial) version of the type in the transition tree.
// To do this, on each rewrite:
// - Search the root of the transition tree using FindRootMap.
// - Find |target_map|, the newest matching version of this map using the keys
// in the |old_map|'s descriptor array to walk the transition tree.
// - Merge/generalize the descriptor array of the |old_map| and |target_map|.
// - Generalize the |modify_index| descriptor using |new_representation| and
// |new_field_type|.
// - Walk the tree again starting from the root towards |target_map|. Stop at
// |split_map|, the first map who's descriptor array does not match the merged
// descriptor array.
// - If |target_map| == |split_map|, |target_map| is in the expected state.
// Return it.
// - Otherwise, invalidate the outdated transition target from |target_map|, and
// replace its transition tree with a new branch for the updated descriptors.
Handle<Map> Map::GeneralizeRepresentation(Handle<Map> old_map,
int modify_index,
Representation new_representation,
Handle<HeapType> new_field_type,
StoreMode store_mode) {
Isolate* isolate = old_map->GetIsolate();
Handle<DescriptorArray> old_descriptors(
old_map->instance_descriptors(), isolate);
int old_nof = old_map->NumberOfOwnDescriptors();
PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
Representation old_representation = old_details.representation();
// It's fine to transition from None to anything but double without any
// modification to the object, because the default uninitialized value for
// representation None can be overwritten by both smi and tagged values.
// Doubles, however, would require a box allocation.
if (old_representation.IsNone() &&
!new_representation.IsNone() &&
!new_representation.IsDouble()) {
DCHECK(old_details.type() == FIELD);
DCHECK(old_descriptors->GetFieldType(modify_index)->NowIs(
HeapType::None()));
if (FLAG_trace_generalization) {
old_map->PrintGeneralization(
stdout, "uninitialized field",
modify_index, old_map->NumberOfOwnDescriptors(),
old_map->NumberOfOwnDescriptors(), false,
old_representation, new_representation,
old_descriptors->GetFieldType(modify_index), *new_field_type);
}
old_descriptors->SetRepresentation(modify_index, new_representation);
old_descriptors->SetValue(modify_index, *new_field_type);
return old_map;
}
// Check the state of the root map.
Handle<Map> root_map(old_map->FindRootMap(), isolate);
if (!old_map->EquivalentToForTransition(*root_map)) {
return CopyGeneralizeAllRepresentations(
old_map, modify_index, store_mode, "not equivalent");
}
int root_nof = root_map->NumberOfOwnDescriptors();
if (modify_index < root_nof) {
PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
if ((old_details.type() != FIELD && store_mode == FORCE_FIELD) ||
(old_details.type() == FIELD &&
(!new_field_type->NowIs(old_descriptors->GetFieldType(modify_index)) ||
!new_representation.fits_into(old_details.representation())))) {
return CopyGeneralizeAllRepresentations(
old_map, modify_index, store_mode, "root modification");
}
}
Handle<Map> target_map = root_map;
for (int i = root_nof; i < old_nof; ++i) {
int j = target_map->SearchTransition(old_descriptors->GetKey(i));
if (j == TransitionArray::kNotFound) break;
Handle<Map> tmp_map(target_map->GetTransition(j), isolate);
Handle<DescriptorArray> tmp_descriptors = handle(
tmp_map->instance_descriptors(), isolate);
// Check if target map is incompatible.
PropertyDetails old_details = old_descriptors->GetDetails(i);
PropertyDetails tmp_details = tmp_descriptors->GetDetails(i);
PropertyType old_type = old_details.type();
PropertyType tmp_type = tmp_details.type();
if (tmp_details.attributes() != old_details.attributes() ||
((tmp_type == CALLBACKS || old_type == CALLBACKS) &&
(tmp_type != old_type ||
tmp_descriptors->GetValue(i) != old_descriptors->GetValue(i)))) {
return CopyGeneralizeAllRepresentations(
old_map, modify_index, store_mode, "incompatible");
}
Representation old_representation = old_details.representation();
Representation tmp_representation = tmp_details.representation();
if (!old_representation.fits_into(tmp_representation) ||
(!new_representation.fits_into(tmp_representation) &&
modify_index == i)) {
break;
}
if (tmp_type == FIELD) {
// Generalize the field type as necessary.
Handle<HeapType> old_field_type = (old_type == FIELD)
? handle(old_descriptors->GetFieldType(i), isolate)
: old_descriptors->GetValue(i)->OptimalType(
isolate, tmp_representation);
if (modify_index == i) {
old_field_type = GeneralizeFieldType(
new_field_type, old_field_type, isolate);
}
GeneralizeFieldType(tmp_map, i, old_field_type);
} else if (tmp_type == CONSTANT) {
if (old_type != CONSTANT ||
old_descriptors->GetConstant(i) != tmp_descriptors->GetConstant(i)) {
break;
}
} else {
DCHECK_EQ(tmp_type, old_type);
DCHECK_EQ(tmp_descriptors->GetValue(i), old_descriptors->GetValue(i));
}
target_map = tmp_map;
}
// Directly change the map if the target map is more general.
Handle<DescriptorArray> target_descriptors(
target_map->instance_descriptors(), isolate);
int target_nof = target_map->NumberOfOwnDescriptors();
if (target_nof == old_nof &&
(store_mode != FORCE_FIELD ||
target_descriptors->GetDetails(modify_index).type() == FIELD)) {
DCHECK(modify_index < target_nof);
DCHECK(new_representation.fits_into(
target_descriptors->GetDetails(modify_index).representation()));
DCHECK(target_descriptors->GetDetails(modify_index).type() != FIELD ||
new_field_type->NowIs(
target_descriptors->GetFieldType(modify_index)));
return target_map;
}
// Find the last compatible target map in the transition tree.
for (int i = target_nof; i < old_nof; ++i) {
int j = target_map->SearchTransition(old_descriptors->GetKey(i));
if (j == TransitionArray::kNotFound) break;
Handle<Map> tmp_map(target_map->GetTransition(j), isolate);
Handle<DescriptorArray> tmp_descriptors(
tmp_map->instance_descriptors(), isolate);
// Check if target map is compatible.
PropertyDetails old_details = old_descriptors->GetDetails(i);
PropertyDetails tmp_details = tmp_descriptors->GetDetails(i);
if (tmp_details.attributes() != old_details.attributes() ||
((tmp_details.type() == CALLBACKS || old_details.type() == CALLBACKS) &&
(tmp_details.type() != old_details.type() ||
tmp_descriptors->GetValue(i) != old_descriptors->GetValue(i)))) {
return CopyGeneralizeAllRepresentations(
old_map, modify_index, store_mode, "incompatible");
}
target_map = tmp_map;
}
target_nof = target_map->NumberOfOwnDescriptors();
target_descriptors = handle(target_map->instance_descriptors(), isolate);
// Allocate a new descriptor array large enough to hold the required
// descriptors, with minimally the exact same size as the old descriptor
// array.
int new_slack = Max(
old_nof, old_descriptors->number_of_descriptors()) - old_nof;
Handle<DescriptorArray> new_descriptors = DescriptorArray::Allocate(
isolate, old_nof, new_slack);
DCHECK(new_descriptors->length() > target_descriptors->length() ||
new_descriptors->NumberOfSlackDescriptors() > 0 ||
new_descriptors->number_of_descriptors() ==
old_descriptors->number_of_descriptors());
DCHECK(new_descriptors->number_of_descriptors() == old_nof);
// 0 -> |root_nof|
int current_offset = 0;
for (int i = 0; i < root_nof; ++i) {
PropertyDetails old_details = old_descriptors->GetDetails(i);
if (old_details.type() == FIELD) current_offset++;
Descriptor d(handle(old_descriptors->GetKey(i), isolate),
handle(old_descriptors->GetValue(i), isolate),
old_details);
new_descriptors->Set(i, &d);
}
// |root_nof| -> |target_nof|
for (int i = root_nof; i < target_nof; ++i) {
Handle<Name> target_key(target_descriptors->GetKey(i), isolate);
PropertyDetails old_details = old_descriptors->GetDetails(i);
PropertyDetails target_details = target_descriptors->GetDetails(i);
target_details = target_details.CopyWithRepresentation(
old_details.representation().generalize(
target_details.representation()));
if (modify_index == i) {
target_details = target_details.CopyWithRepresentation(
new_representation.generalize(target_details.representation()));
}
DCHECK_EQ(old_details.attributes(), target_details.attributes());
if (old_details.type() == FIELD ||
target_details.type() == FIELD ||
(modify_index == i && store_mode == FORCE_FIELD) ||
(target_descriptors->GetValue(i) != old_descriptors->GetValue(i))) {
Handle<HeapType> old_field_type = (old_details.type() == FIELD)
? handle(old_descriptors->GetFieldType(i), isolate)
: old_descriptors->GetValue(i)->OptimalType(
isolate, target_details.representation());
Handle<HeapType> target_field_type = (target_details.type() == FIELD)
? handle(target_descriptors->GetFieldType(i), isolate)
: target_descriptors->GetValue(i)->OptimalType(
isolate, target_details.representation());
target_field_type = GeneralizeFieldType(
target_field_type, old_field_type, isolate);
if (modify_index == i) {
target_field_type = GeneralizeFieldType(
target_field_type, new_field_type, isolate);
}
FieldDescriptor d(target_key,
current_offset++,
target_field_type,
target_details.attributes(),
target_details.representation());
new_descriptors->Set(i, &d);
} else {
DCHECK_NE(FIELD, target_details.type());
Descriptor d(target_key,
handle(target_descriptors->GetValue(i), isolate),
target_details);
new_descriptors->Set(i, &d);
}
}
// |target_nof| -> |old_nof|
for (int i = target_nof; i < old_nof; ++i) {
PropertyDetails old_details = old_descriptors->GetDetails(i);
Handle<Name> old_key(old_descriptors->GetKey(i), isolate);
if (modify_index == i) {
old_details = old_details.CopyWithRepresentation(
new_representation.generalize(old_details.representation()));
}
if (old_details.type() == FIELD) {
Handle<HeapType> old_field_type(
old_descriptors->GetFieldType(i), isolate);
if (modify_index == i) {
old_field_type = GeneralizeFieldType(
old_field_type, new_field_type, isolate);
}
FieldDescriptor d(old_key,
current_offset++,
old_field_type,
old_details.attributes(),
old_details.representation());
new_descriptors->Set(i, &d);
} else {
DCHECK(old_details.type() == CONSTANT || old_details.type() == CALLBACKS);
if (modify_index == i && store_mode == FORCE_FIELD) {
FieldDescriptor d(old_key,
current_offset++,
GeneralizeFieldType(
old_descriptors->GetValue(i)->OptimalType(
isolate, old_details.representation()),
new_field_type, isolate),
old_details.attributes(),
old_details.representation());
new_descriptors->Set(i, &d);
} else {
DCHECK_NE(FIELD, old_details.type());
Descriptor d(old_key,
handle(old_descriptors->GetValue(i), isolate),
old_details);
new_descriptors->Set(i, &d);
}
}
}
new_descriptors->Sort();
DCHECK(store_mode != FORCE_FIELD ||
new_descriptors->GetDetails(modify_index).type() == FIELD);
Handle<Map> split_map(root_map->FindLastMatchMap(
root_nof, old_nof, *new_descriptors), isolate);
int split_nof = split_map->NumberOfOwnDescriptors();
DCHECK_NE(old_nof, split_nof);
split_map->DeprecateTarget(
old_descriptors->GetKey(split_nof), *new_descriptors);
if (FLAG_trace_generalization) {
PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
PropertyDetails new_details = new_descriptors->GetDetails(modify_index);
Handle<HeapType> old_field_type = (old_details.type() == FIELD)
? handle(old_descriptors->GetFieldType(modify_index), isolate)
: HeapType::Constant(handle(old_descriptors->GetValue(modify_index),
isolate), isolate);
Handle<HeapType> new_field_type = (new_details.type() == FIELD)
? handle(new_descriptors->GetFieldType(modify_index), isolate)
: HeapType::Constant(handle(new_descriptors->GetValue(modify_index),
isolate), isolate);
old_map->PrintGeneralization(
stdout, "", modify_index, split_nof, old_nof,
old_details.type() == CONSTANT && store_mode == FORCE_FIELD,
old_details.representation(), new_details.representation(),
*old_field_type, *new_field_type);
}
// Add missing transitions.
Handle<Map> new_map = split_map;
for (int i = split_nof; i < old_nof; ++i) {
new_map = CopyInstallDescriptors(new_map, i, new_descriptors);
}
new_map->set_owns_descriptors(true);
return new_map;
}
// Generalize the representation of all FIELD descriptors.
Handle<Map> Map::GeneralizeAllFieldRepresentations(
Handle<Map> map) {
Handle<DescriptorArray> descriptors(map->instance_descriptors());
for (int i = 0; i < map->NumberOfOwnDescriptors(); ++i) {
if (descriptors->GetDetails(i).type() == FIELD) {
map = GeneralizeRepresentation(map, i, Representation::Tagged(),
HeapType::Any(map->GetIsolate()),
FORCE_FIELD);
}
}
return map;
}
// static
MaybeHandle<Map> Map::TryUpdate(Handle<Map> map) {
Handle<Map> proto_map(map);
while (proto_map->prototype()->IsJSObject()) {
Handle<JSObject> holder(JSObject::cast(proto_map->prototype()));
proto_map = Handle<Map>(holder->map());
if (proto_map->is_deprecated() && JSObject::TryMigrateInstance(holder)) {
proto_map = Handle<Map>(holder->map());
}
}
return TryUpdateInternal(map);
}
// static
Handle<Map> Map::Update(Handle<Map> map) {
if (!map->is_deprecated()) return map;
return GeneralizeRepresentation(map, 0, Representation::None(),
HeapType::None(map->GetIsolate()),
ALLOW_AS_CONSTANT);
}
// static
MaybeHandle<Map> Map::TryUpdateInternal(Handle<Map> old_map) {
DisallowHeapAllocation no_allocation;
DisallowDeoptimization no_deoptimization(old_map->GetIsolate());
if (!old_map->is_deprecated()) return old_map;
// Check the state of the root map.
Map* root_map = old_map->FindRootMap();
if (!old_map->EquivalentToForTransition(root_map)) return MaybeHandle<Map>();
int root_nof = root_map->NumberOfOwnDescriptors();
int old_nof = old_map->NumberOfOwnDescriptors();
DescriptorArray* old_descriptors = old_map->instance_descriptors();
Map* new_map = root_map;
for (int i = root_nof; i < old_nof; ++i) {
int j = new_map->SearchTransition(old_descriptors->GetKey(i));
if (j == TransitionArray::kNotFound) return MaybeHandle<Map>();
new_map = new_map->GetTransition(j);
DescriptorArray* new_descriptors = new_map->instance_descriptors();
PropertyDetails new_details = new_descriptors->GetDetails(i);
PropertyDetails old_details = old_descriptors->GetDetails(i);
if (old_details.attributes() != new_details.attributes() ||
!old_details.representation().fits_into(new_details.representation())) {
return MaybeHandle<Map>();
}
PropertyType new_type = new_details.type();
PropertyType old_type = old_details.type();
Object* new_value = new_descriptors->GetValue(i);
Object* old_value = old_descriptors->GetValue(i);
switch (new_type) {
case FIELD:
if ((old_type == FIELD &&
!HeapType::cast(old_value)->NowIs(HeapType::cast(new_value))) ||
(old_type == CONSTANT &&
!HeapType::cast(new_value)->NowContains(old_value)) ||
(old_type == CALLBACKS &&
!HeapType::Any()->Is(HeapType::cast(new_value)))) {
return MaybeHandle<Map>();
}
break;
case CONSTANT:
case CALLBACKS:
if (old_type != new_type || old_value != new_value) {
return MaybeHandle<Map>();
}
break;
case NORMAL:
UNREACHABLE();
}
}
if (new_map->NumberOfOwnDescriptors() != old_nof) return MaybeHandle<Map>();
return handle(new_map);
}
MaybeHandle<Object> JSObject::SetPropertyWithInterceptor(LookupIterator* it,
Handle<Object> value) {
// TODO(rossberg): Support symbols in the API.
if (it->name()->IsSymbol()) return value;
Handle<String> name_string = Handle<String>::cast(it->name());
Handle<JSObject> holder = it->GetHolder<JSObject>();
Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor());
if (interceptor->setter()->IsUndefined()) return MaybeHandle<Object>();
LOG(it->isolate(),
ApiNamedPropertyAccess("interceptor-named-set", *holder, *name_string));
PropertyCallbackArguments args(it->isolate(), interceptor->data(), *holder,
*holder);
v8::NamedPropertySetterCallback setter =
v8::ToCData<v8::NamedPropertySetterCallback>(interceptor->setter());
v8::Handle<v8::Value> result = args.Call(
setter, v8::Utils::ToLocal(name_string), v8::Utils::ToLocal(value));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(it->isolate(), Object);
if (!result.IsEmpty()) return value;
return MaybeHandle<Object>();
}
MaybeHandle<Object> Object::SetProperty(Handle<Object> object,
Handle<Name> name, Handle<Object> value,
StrictMode strict_mode,
StoreFromKeyed store_mode) {
LookupIterator it(object, name);
return SetProperty(&it, value, strict_mode, store_mode);
}
MaybeHandle<Object> Object::SetProperty(LookupIterator* it,
Handle<Object> value,
StrictMode strict_mode,
StoreFromKeyed store_mode) {
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc(it->isolate());
bool done = false;
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::NOT_FOUND:
UNREACHABLE();
case LookupIterator::ACCESS_CHECK:
// TODO(verwaest): Remove the distinction. This is mostly bogus since we
// don't know whether we'll want to fetch attributes or call a setter
// until we find the property.
if (it->HasAccess(v8::ACCESS_SET)) break;
return JSObject::SetPropertyWithFailedAccessCheck(it, value,
strict_mode);
case LookupIterator::JSPROXY:
if (it->HolderIsReceiverOrHiddenPrototype()) {
return JSProxy::SetPropertyWithHandler(it->GetHolder<JSProxy>(),
it->GetReceiver(), it->name(),
value, strict_mode);
} else {
// TODO(verwaest): Use the MaybeHandle to indicate result.
bool has_result = false;
MaybeHandle<Object> maybe_result =
JSProxy::SetPropertyViaPrototypesWithHandler(
it->GetHolder<JSProxy>(), it->GetReceiver(), it->name(),
value, strict_mode, &has_result);
if (has_result) return maybe_result;
done = true;
}
break;
case LookupIterator::INTERCEPTOR:
if (it->HolderIsReceiverOrHiddenPrototype()) {
MaybeHandle<Object> maybe_result =
JSObject::SetPropertyWithInterceptor(it, value);
if (!maybe_result.is_null()) return maybe_result;
if (it->isolate()->has_pending_exception()) return maybe_result;
} else {
Maybe<PropertyAttributes> maybe_attributes =
JSObject::GetPropertyAttributesWithInterceptor(
it->GetHolder<JSObject>(), it->GetReceiver(), it->name());
if (!maybe_attributes.has_value) return MaybeHandle<Object>();
done = maybe_attributes.value != ABSENT;
if (done && (maybe_attributes.value & READ_ONLY) != 0) {
return WriteToReadOnlyProperty(it, value, strict_mode);
}
}
break;
case LookupIterator::ACCESSOR:
if (it->property_details().IsReadOnly()) {
return WriteToReadOnlyProperty(it, value, strict_mode);
}
if (it->HolderIsReceiverOrHiddenPrototype() ||
!it->GetAccessors()->IsDeclaredAccessorInfo()) {
return SetPropertyWithAccessor(it->GetReceiver(), it->name(), value,
it->GetHolder<JSObject>(),
it->GetAccessors(), strict_mode);
}
done = true;
break;
case LookupIterator::DATA:
if (it->property_details().IsReadOnly()) {
return WriteToReadOnlyProperty(it, value, strict_mode);
}
if (it->HolderIsReceiverOrHiddenPrototype()) {
return SetDataProperty(it, value);
}
done = true;
break;
case LookupIterator::TRANSITION:
done = true;
break;
}
if (done) break;
}
// If the receiver is the JSGlobalObject, the store was contextual. In case
// the property did not exist yet on the global object itself, we have to
// throw a reference error in strict mode.
if (it->GetReceiver()->IsJSGlobalObject() && strict_mode == STRICT) {
Handle<Object> args[1] = {it->name()};
THROW_NEW_ERROR(it->isolate(),
NewReferenceError("not_defined", HandleVector(args, 1)),
Object);
}
return AddDataProperty(it, value, NONE, strict_mode, store_mode);
}
MaybeHandle<Object> Object::WriteToReadOnlyProperty(LookupIterator* it,
Handle<Object> value,
StrictMode strict_mode) {
if (strict_mode != STRICT) return value;
Handle<Object> args[] = {it->name(), it->GetReceiver()};
THROW_NEW_ERROR(it->isolate(),
NewTypeError("strict_read_only_property",
HandleVector(args, arraysize(args))),
Object);
}
Handle<Object> Object::SetDataProperty(LookupIterator* it,
Handle<Object> value) {
// Proxies are handled on the WithHandler path. Other non-JSObjects cannot
// have own properties.
Handle<JSObject> receiver = Handle<JSObject>::cast(it->GetReceiver());
// Store on the holder which may be hidden behind the receiver.
DCHECK(it->HolderIsReceiverOrHiddenPrototype());
// Old value for the observation change record.
// Fetch before transforming the object since the encoding may become
// incompatible with what's cached in |it|.
bool is_observed =
receiver->map()->is_observed() &&
!it->name().is_identical_to(it->factory()->hidden_string());
MaybeHandle<Object> maybe_old;
if (is_observed) maybe_old = it->GetDataValue();
// Possibly migrate to the most up-to-date map that will be able to store
// |value| under it->name().
it->PrepareForDataProperty(value);
// Write the property value.
it->WriteDataValue(value);
// Send the change record if there are observers.
if (is_observed && !value->SameValue(*maybe_old.ToHandleChecked())) {
JSObject::EnqueueChangeRecord(receiver, "update", it->name(),
maybe_old.ToHandleChecked());
}
return value;
}
MaybeHandle<Object> Object::AddDataProperty(LookupIterator* it,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode,
StoreFromKeyed store_mode) {
DCHECK(!it->GetReceiver()->IsJSProxy());
if (!it->GetReceiver()->IsJSObject()) {
// TODO(verwaest): Throw a TypeError with a more specific message.
return WriteToReadOnlyProperty(it, value, strict_mode);
}
Handle<JSObject> receiver = it->GetStoreTarget();
// If the receiver is a JSGlobalProxy, store on the prototype (JSGlobalObject)
// instead. If the prototype is Null, the proxy is detached.
if (receiver->IsJSGlobalProxy()) return value;
// Possibly migrate to the most up-to-date map that will be able to store
// |value| under it->name() with |attributes|.
it->PrepareTransitionToDataProperty(value, attributes, store_mode);
if (it->state() != LookupIterator::TRANSITION) {
if (strict_mode == SLOPPY) return value;
Handle<Object> args[1] = {it->name()};
THROW_NEW_ERROR(it->isolate(),
NewTypeError("object_not_extensible",
HandleVector(args, arraysize(args))),
Object);
}
it->ApplyTransitionToDataProperty();
// TODO(verwaest): Encapsulate dictionary handling better.
if (receiver->map()->is_dictionary_map()) {
// TODO(verwaest): Probably should ensure this is done beforehand.
it->InternalizeName();
JSObject::AddSlowProperty(receiver, it->name(), value, attributes);
} else {
// Write the property value.
it->WriteDataValue(value);
}
// Send the change record if there are observers.
if (receiver->map()->is_observed() &&
!it->name().is_identical_to(it->factory()->hidden_string())) {
JSObject::EnqueueChangeRecord(receiver, "add", it->name(),
it->factory()->the_hole_value());
}
return value;
}
MaybeHandle<Object> JSObject::SetElementWithCallbackSetterInPrototypes(
Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
bool* found,
StrictMode strict_mode) {
Isolate *isolate = object->GetIsolate();
for (PrototypeIterator iter(isolate, object); !iter.IsAtEnd();
iter.Advance()) {
if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
return JSProxy::SetPropertyViaPrototypesWithHandler(
Handle<JSProxy>::cast(PrototypeIterator::GetCurrent(iter)), object,
isolate->factory()->Uint32ToString(index), // name
value, strict_mode, found);
}
Handle<JSObject> js_proto =
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter));
if (!js_proto->HasDictionaryElements()) {
continue;
}
Handle<SeededNumberDictionary> dictionary(js_proto->element_dictionary());
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS) {
*found = true;
Handle<Object> structure(dictionary->ValueAt(entry), isolate);
return SetElementWithCallback(object, structure, index, value, js_proto,
strict_mode);
}
}
}
*found = false;
return isolate->factory()->the_hole_value();
}
void Map::EnsureDescriptorSlack(Handle<Map> map, int slack) {
// Only supports adding slack to owned descriptors.
DCHECK(map->owns_descriptors());
Handle<DescriptorArray> descriptors(map->instance_descriptors());
int old_size = map->NumberOfOwnDescriptors();
if (slack <= descriptors->NumberOfSlackDescriptors()) return;
Handle<DescriptorArray> new_descriptors = DescriptorArray::CopyUpTo(
descriptors, old_size, slack);
if (old_size == 0) {
map->set_instance_descriptors(*new_descriptors);
return;
}
// If the source descriptors had an enum cache we copy it. This ensures
// that the maps to which we push the new descriptor array back can rely
// on a cache always being available once it is set. If the map has more
// enumerated descriptors than available in the original cache, the cache
// will be lazily replaced by the extended cache when needed.
if (descriptors->HasEnumCache()) {
new_descriptors->CopyEnumCacheFrom(*descriptors);
}
// Replace descriptors by new_descriptors in all maps that share it.
map->GetHeap()->incremental_marking()->RecordWrites(*descriptors);
Map* walk_map;
for (Object* current = map->GetBackPointer();
!current->IsUndefined();
current = walk_map->GetBackPointer()) {
walk_map = Map::cast(current);
if (walk_map->instance_descriptors() != *descriptors) break;
walk_map->set_instance_descriptors(*new_descriptors);
}
map->set_instance_descriptors(*new_descriptors);
}
template<class T>
static int AppendUniqueCallbacks(NeanderArray* callbacks,
Handle<typename T::Array> array,
int valid_descriptors) {
int nof_callbacks = callbacks->length();
Isolate* isolate = array->GetIsolate();
// Ensure the keys are unique names before writing them into the
// instance descriptor. Since it may cause a GC, it has to be done before we
// temporarily put the heap in an invalid state while appending descriptors.
for (int i = 0; i < nof_callbacks; ++i) {
Handle<AccessorInfo> entry(AccessorInfo::cast(callbacks->get(i)));
if (entry->name()->IsUniqueName()) continue;
Handle<String> key =
isolate->factory()->InternalizeString(
Handle<String>(String::cast(entry->name())));
entry->set_name(*key);
}
// Fill in new callback descriptors. Process the callbacks from
// back to front so that the last callback with a given name takes
// precedence over previously added callbacks with that name.
for (int i = nof_callbacks - 1; i >= 0; i--) {
Handle<AccessorInfo> entry(AccessorInfo::cast(callbacks->get(i)));
Handle<Name> key(Name::cast(entry->name()));
// Check if a descriptor with this name already exists before writing.
if (!T::Contains(key, entry, valid_descriptors, array)) {
T::Insert(key, entry, valid_descriptors, array);
valid_descriptors++;
}
}
return valid_descriptors;
}
struct DescriptorArrayAppender {
typedef DescriptorArray Array;
static bool Contains(Handle<Name> key,
Handle<AccessorInfo> entry,
int valid_descriptors,
Handle<DescriptorArray> array) {
DisallowHeapAllocation no_gc;
return array->Search(*key, valid_descriptors) != DescriptorArray::kNotFound;
}
static void Insert(Handle<Name> key,
Handle<AccessorInfo> entry,
int valid_descriptors,
Handle<DescriptorArray> array) {
DisallowHeapAllocation no_gc;
CallbacksDescriptor desc(key, entry, entry->property_attributes());
array->Append(&desc);
}
};
struct FixedArrayAppender {
typedef FixedArray Array;
static bool Contains(Handle<Name> key,
Handle<AccessorInfo> entry,
int valid_descriptors,
Handle<FixedArray> array) {
for (int i = 0; i < valid_descriptors; i++) {
if (*key == AccessorInfo::cast(array->get(i))->name()) return true;
}
return false;
}
static void Insert(Handle<Name> key,
Handle<AccessorInfo> entry,
int valid_descriptors,
Handle<FixedArray> array) {
DisallowHeapAllocation no_gc;
array->set(valid_descriptors, *entry);
}
};
void Map::AppendCallbackDescriptors(Handle<Map> map,
Handle<Object> descriptors) {
int nof = map->NumberOfOwnDescriptors();
Handle<DescriptorArray> array(map->instance_descriptors());
NeanderArray callbacks(descriptors);
DCHECK(array->NumberOfSlackDescriptors() >= callbacks.length());
nof = AppendUniqueCallbacks<DescriptorArrayAppender>(&callbacks, array, nof);
map->SetNumberOfOwnDescriptors(nof);
}
int AccessorInfo::AppendUnique(Handle<Object> descriptors,
Handle<FixedArray> array,
int valid_descriptors) {
NeanderArray callbacks(descriptors);
DCHECK(array->length() >= callbacks.length() + valid_descriptors);
return AppendUniqueCallbacks<FixedArrayAppender>(&callbacks,
array,
valid_descriptors);
}
static bool ContainsMap(MapHandleList* maps, Handle<Map> map) {
DCHECK(!map.is_null());
for (int i = 0; i < maps->length(); ++i) {
if (!maps->at(i).is_null() && maps->at(i).is_identical_to(map)) return true;
}
return false;
}
template <class T>
static Handle<T> MaybeNull(T* p) {
if (p == NULL) return Handle<T>::null();
return Handle<T>(p);
}
Handle<Map> Map::FindTransitionedMap(MapHandleList* candidates) {
ElementsKind kind = elements_kind();
Handle<Map> transitioned_map = Handle<Map>::null();
Handle<Map> current_map(this);
bool packed = IsFastPackedElementsKind(kind);
if (IsTransitionableFastElementsKind(kind)) {
while (CanTransitionToMoreGeneralFastElementsKind(kind, false)) {
kind = GetNextMoreGeneralFastElementsKind(kind, false);
Handle<Map> maybe_transitioned_map =
MaybeNull(current_map->LookupElementsTransitionMap(kind));
if (maybe_transitioned_map.is_null()) break;
if (ContainsMap(candidates, maybe_transitioned_map) &&
(packed || !IsFastPackedElementsKind(kind))) {
transitioned_map = maybe_transitioned_map;
if (!IsFastPackedElementsKind(kind)) packed = false;
}
current_map = maybe_transitioned_map;
}
}
return transitioned_map;
}
static Map* FindClosestElementsTransition(Map* map, ElementsKind to_kind) {
Map* current_map = map;
int target_kind =
IsFastElementsKind(to_kind) || IsExternalArrayElementsKind(to_kind)
? to_kind
: TERMINAL_FAST_ELEMENTS_KIND;
// Support for legacy API: SetIndexedPropertiesTo{External,Pixel}Data
// allows to change elements from arbitrary kind to any ExternalArray
// elements kind. Satisfy its requirements, checking whether we already
// have the cached transition.
if (IsExternalArrayElementsKind(to_kind) &&
!IsFixedTypedArrayElementsKind(map->elements_kind())) {
if (map->HasElementsTransition()) {
Map* next_map = map->elements_transition_map();
if (next_map->elements_kind() == to_kind) return next_map;
}
return map;
}
ElementsKind kind = map->elements_kind();
while (kind != target_kind) {
kind = GetNextTransitionElementsKind(kind);
if (!current_map->HasElementsTransition()) return current_map;
current_map = current_map->elements_transition_map();
}
if (to_kind != kind && current_map->HasElementsTransition()) {
DCHECK(to_kind == DICTIONARY_ELEMENTS);
Map* next_map = current_map->elements_transition_map();
if (next_map->elements_kind() == to_kind) return next_map;
}
DCHECK(current_map->elements_kind() == target_kind);
return current_map;
}
Map* Map::LookupElementsTransitionMap(ElementsKind to_kind) {
Map* to_map = FindClosestElementsTransition(this, to_kind);
if (to_map->elements_kind() == to_kind) return to_map;
return NULL;
}
bool Map::IsMapInArrayPrototypeChain() {
Isolate* isolate = GetIsolate();
if (isolate->initial_array_prototype()->map() == this) {
return true;
}
if (isolate->initial_object_prototype()->map() == this) {
return true;
}
return false;
}
static Handle<Map> AddMissingElementsTransitions(Handle<Map> map,
ElementsKind to_kind) {
DCHECK(IsTransitionElementsKind(map->elements_kind()));
Handle<Map> current_map = map;
ElementsKind kind = map->elements_kind();
if (!map->is_prototype_map()) {
while (kind != to_kind && !IsTerminalElementsKind(kind)) {
kind = GetNextTransitionElementsKind(kind);
current_map =
Map::CopyAsElementsKind(current_map, kind, INSERT_TRANSITION);
}
}
// In case we are exiting the fast elements kind system, just add the map in
// the end.
if (kind != to_kind) {
current_map = Map::CopyAsElementsKind(
current_map, to_kind, INSERT_TRANSITION);
}
DCHECK(current_map->elements_kind() == to_kind);
return current_map;
}
Handle<Map> Map::TransitionElementsTo(Handle<Map> map,
ElementsKind to_kind) {
ElementsKind from_kind = map->elements_kind();
if (from_kind == to_kind) return map;
Isolate* isolate = map->GetIsolate();
Context* native_context = isolate->context()->native_context();
Object* maybe_array_maps = native_context->js_array_maps();
if (maybe_array_maps->IsFixedArray()) {
DisallowHeapAllocation no_gc;
FixedArray* array_maps = FixedArray::cast(maybe_array_maps);
if (array_maps->get(from_kind) == *map) {
Object* maybe_transitioned_map = array_maps->get(to_kind);
if (maybe_transitioned_map->IsMap()) {
return handle(Map::cast(maybe_transitioned_map));
}
}
}
return TransitionElementsToSlow(map, to_kind);
}
Handle<Map> Map::TransitionElementsToSlow(Handle<Map> map,
ElementsKind to_kind) {
ElementsKind from_kind = map->elements_kind();
if (from_kind == to_kind) {
return map;
}
bool allow_store_transition =
// Only remember the map transition if there is not an already existing
// non-matching element transition.
!map->IsUndefined() && !map->is_dictionary_map() &&
IsTransitionElementsKind(from_kind);
// Only store fast element maps in ascending generality.
if (IsFastElementsKind(to_kind)) {
allow_store_transition &=
IsTransitionableFastElementsKind(from_kind) &&
IsMoreGeneralElementsKindTransition(from_kind, to_kind);
}
if (!allow_store_transition) {
return Map::CopyAsElementsKind(map, to_kind, OMIT_TRANSITION);
}
return Map::AsElementsKind(map, to_kind);
}
// static
Handle<Map> Map::AsElementsKind(Handle<Map> map, ElementsKind kind) {
Handle<Map> closest_map(FindClosestElementsTransition(*map, kind));
if (closest_map->elements_kind() == kind) {
return closest_map;
}
return AddMissingElementsTransitions(closest_map, kind);
}
Handle<Map> JSObject::GetElementsTransitionMap(Handle<JSObject> object,
ElementsKind to_kind) {
Handle<Map> map(object->map());
return Map::TransitionElementsTo(map, to_kind);
}
Maybe<bool> JSProxy::HasPropertyWithHandler(Handle<JSProxy> proxy,
Handle<Name> name) {
Isolate* isolate = proxy->GetIsolate();
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) return maybe(false);
Handle<Object> args[] = { name };
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(
isolate, result, CallTrap(proxy, "has", isolate->derived_has_trap(),
arraysize(args), args),
Maybe<bool>());
return maybe(result->BooleanValue());
}
MaybeHandle<Object> JSProxy::SetPropertyWithHandler(Handle<JSProxy> proxy,
Handle<Object> receiver,
Handle<Name> name,
Handle<Object> value,
StrictMode strict_mode) {
Isolate* isolate = proxy->GetIsolate();
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) return value;
Handle<Object> args[] = { receiver, name, value };
RETURN_ON_EXCEPTION(
isolate,
CallTrap(proxy,
"set",
isolate->derived_set_trap(),
arraysize(args),
args),
Object);
return value;
}
MaybeHandle<Object> JSProxy::SetPropertyViaPrototypesWithHandler(
Handle<JSProxy> proxy, Handle<Object> receiver, Handle<Name> name,
Handle<Object> value, StrictMode strict_mode, bool* done) {
Isolate* isolate = proxy->GetIsolate();
Handle<Object> handler(proxy->handler(), isolate); // Trap might morph proxy.
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) {
*done = false;
return isolate->factory()->the_hole_value();
}
*done = true; // except where redefined...
Handle<Object> args[] = { name };
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
CallTrap(proxy,
"getPropertyDescriptor",
Handle<Object>(),
arraysize(args),
args),
Object);
if (result->IsUndefined()) {
*done = false;
return isolate->factory()->the_hole_value();
}
// Emulate [[GetProperty]] semantics for proxies.
Handle<Object> argv[] = { result };
Handle<Object> desc;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, desc,
Execution::Call(isolate,
isolate->to_complete_property_descriptor(),
result,
arraysize(argv),
argv),
Object);
// [[GetProperty]] requires to check that all properties are configurable.
Handle<String> configurable_name =
isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("configurable_"));
Handle<Object> configurable =
Object::GetProperty(desc, configurable_name).ToHandleChecked();
DCHECK(configurable->IsBoolean());
if (configurable->IsFalse()) {
Handle<String> trap = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("getPropertyDescriptor"));
Handle<Object> args[] = { handler, trap, name };
THROW_NEW_ERROR(isolate, NewTypeError("proxy_prop_not_configurable",
HandleVector(args, arraysize(args))),
Object);
}
DCHECK(configurable->IsTrue());
// Check for DataDescriptor.
Handle<String> hasWritable_name =
isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("hasWritable_"));
Handle<Object> hasWritable =
Object::GetProperty(desc, hasWritable_name).ToHandleChecked();
DCHECK(hasWritable->IsBoolean());
if (hasWritable->IsTrue()) {
Handle<String> writable_name = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("writable_"));
Handle<Object> writable =
Object::GetProperty(desc, writable_name).ToHandleChecked();
DCHECK(writable->IsBoolean());
*done = writable->IsFalse();
if (!*done) return isolate->factory()->the_hole_value();
if (strict_mode == SLOPPY) return value;
Handle<Object> args[] = { name, receiver };
THROW_NEW_ERROR(isolate, NewTypeError("strict_read_only_property",
HandleVector(args, arraysize(args))),
Object);
}
// We have an AccessorDescriptor.
Handle<String> set_name =
isolate->factory()->InternalizeOneByteString(STATIC_CHAR_VECTOR("set_"));
Handle<Object> setter = Object::GetProperty(desc, set_name).ToHandleChecked();
if (!setter->IsUndefined()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return SetPropertyWithDefinedSetter(
receiver, Handle<JSReceiver>::cast(setter), value);
}
if (strict_mode == SLOPPY) return value;
Handle<Object> args2[] = { name, proxy };
THROW_NEW_ERROR(isolate, NewTypeError("no_setter_in_callback",
HandleVector(args2, arraysize(args2))),
Object);
}
MaybeHandle<Object> JSProxy::DeletePropertyWithHandler(
Handle<JSProxy> proxy, Handle<Name> name, DeleteMode mode) {
Isolate* isolate = proxy->GetIsolate();
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) return isolate->factory()->false_value();
Handle<Object> args[] = { name };
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
CallTrap(proxy,
"delete",
Handle<Object>(),
arraysize(args),
args),
Object);
bool result_bool = result->BooleanValue();
if (mode == STRICT_DELETION && !result_bool) {
Handle<Object> handler(proxy->handler(), isolate);
Handle<String> trap_name = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("delete"));
Handle<Object> args[] = { handler, trap_name };
THROW_NEW_ERROR(isolate, NewTypeError("handler_failed",
HandleVector(args, arraysize(args))),
Object);
}
return isolate->factory()->ToBoolean(result_bool);
}
MaybeHandle<Object> JSProxy::DeleteElementWithHandler(
Handle<JSProxy> proxy, uint32_t index, DeleteMode mode) {
Isolate* isolate = proxy->GetIsolate();
Handle<String> name = isolate->factory()->Uint32ToString(index);
return JSProxy::DeletePropertyWithHandler(proxy, name, mode);
}
Maybe<PropertyAttributes> JSProxy::GetPropertyAttributesWithHandler(
Handle<JSProxy> proxy, Handle<Object> receiver, Handle<Name> name) {
Isolate* isolate = proxy->GetIsolate();
HandleScope scope(isolate);
// TODO(rossberg): adjust once there is a story for symbols vs proxies.
if (name->IsSymbol()) return maybe(ABSENT);
Handle<Object> args[] = { name };
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(
isolate, result,
proxy->CallTrap(proxy, "getPropertyDescriptor", Handle<Object>(),
arraysize(args), args),
Maybe<PropertyAttributes>());
if (result->IsUndefined()) return maybe(ABSENT);
Handle<Object> argv[] = { result };
Handle<Object> desc;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(
isolate, desc,
Execution::Call(isolate, isolate->to_complete_property_descriptor(),
result, arraysize(argv), argv),
Maybe<PropertyAttributes>());
// Convert result to PropertyAttributes.
Handle<String> enum_n = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("enumerable_"));
Handle<Object> enumerable;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, enumerable,
Object::GetProperty(desc, enum_n),
Maybe<PropertyAttributes>());
Handle<String> conf_n = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("configurable_"));
Handle<Object> configurable;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, configurable,
Object::GetProperty(desc, conf_n),
Maybe<PropertyAttributes>());
Handle<String> writ_n = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("writable_"));
Handle<Object> writable;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, writable,
Object::GetProperty(desc, writ_n),
Maybe<PropertyAttributes>());
if (!writable->BooleanValue()) {
Handle<String> set_n = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("set_"));
Handle<Object> setter;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, setter,
Object::GetProperty(desc, set_n),
Maybe<PropertyAttributes>());
writable = isolate->factory()->ToBoolean(!setter->IsUndefined());
}
if (configurable->IsFalse()) {
Handle<Object> handler(proxy->handler(), isolate);
Handle<String> trap = isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("getPropertyDescriptor"));
Handle<Object> args[] = { handler, trap, name };
Handle<Object> error;
MaybeHandle<Object> maybe_error = isolate->factory()->NewTypeError(
"proxy_prop_not_configurable", HandleVector(args, arraysize(args)));
if (maybe_error.ToHandle(&error)) isolate->Throw(*error);
return maybe(NONE);
}
int attributes = NONE;
if (!enumerable->BooleanValue()) attributes |= DONT_ENUM;
if (!configurable->BooleanValue()) attributes |= DONT_DELETE;
if (!writable->BooleanValue()) attributes |= READ_ONLY;
return maybe(static_cast<PropertyAttributes>(attributes));
}
Maybe<PropertyAttributes> JSProxy::GetElementAttributeWithHandler(
Handle<JSProxy> proxy, Handle<JSReceiver> receiver, uint32_t index) {
Isolate* isolate = proxy->GetIsolate();
Handle<String> name = isolate->factory()->Uint32ToString(index);
return GetPropertyAttributesWithHandler(proxy, receiver, name);
}
void JSProxy::Fix(Handle<JSProxy> proxy) {
Isolate* isolate = proxy->GetIsolate();
// Save identity hash.
Handle<Object> hash(proxy->GetIdentityHash(), isolate);
if (proxy->IsJSFunctionProxy()) {
isolate->factory()->BecomeJSFunction(proxy);
// Code will be set on the JavaScript side.
} else {
isolate->factory()->BecomeJSObject(proxy);
}
DCHECK(proxy->IsJSObject());
// Inherit identity, if it was present.
if (hash->IsSmi()) {
JSObject::SetIdentityHash(Handle<JSObject>::cast(proxy),
Handle<Smi>::cast(hash));
}
}
MaybeHandle<Object> JSProxy::CallTrap(Handle<JSProxy> proxy,
const char* name,
Handle<Object> derived,
int argc,
Handle<Object> argv[]) {
Isolate* isolate = proxy->GetIsolate();
Handle<Object> handler(proxy->handler(), isolate);
Handle<String> trap_name = isolate->factory()->InternalizeUtf8String(name);
Handle<Object> trap;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, trap,
Object::GetPropertyOrElement(handler, trap_name),
Object);
if (trap->IsUndefined()) {
if (derived.is_null()) {
Handle<Object> args[] = { handler, trap_name };
THROW_NEW_ERROR(isolate,
NewTypeError("handler_trap_missing",
HandleVector(args, arraysize(args))),
Object);
}
trap = Handle<Object>(derived);
}
return Execution::Call(isolate, trap, handler, argc, argv);
}
void JSObject::AllocateStorageForMap(Handle<JSObject> object, Handle<Map> map) {
DCHECK(object->map()->inobject_properties() == map->inobject_properties());
ElementsKind obj_kind = object->map()->elements_kind();
ElementsKind map_kind = map->elements_kind();
if (map_kind != obj_kind) {
ElementsKind to_kind = map_kind;
if (IsMoreGeneralElementsKindTransition(map_kind, obj_kind) ||
IsDictionaryElementsKind(obj_kind)) {
to_kind = obj_kind;
}
if (IsDictionaryElementsKind(to_kind)) {
NormalizeElements(object);
} else {
TransitionElementsKind(object, to_kind);
}
map = Map::AsElementsKind(map, to_kind);
}
JSObject::MigrateToMap(object, map);
}
void JSObject::MigrateInstance(Handle<JSObject> object) {
Handle<Map> original_map(object->map());
Handle<Map> map = Map::Update(original_map);
map->set_migration_target(true);
MigrateToMap(object, map);
if (FLAG_trace_migration) {
object->PrintInstanceMigration(stdout, *original_map, *map);
}
}
// static
bool JSObject::TryMigrateInstance(Handle<JSObject> object) {
Isolate* isolate = object->GetIsolate();
DisallowDeoptimization no_deoptimization(isolate);
Handle<Map> original_map(object->map(), isolate);
Handle<Map> new_map;
if (!Map::TryUpdate(original_map).ToHandle(&new_map)) {
return false;
}
JSObject::MigrateToMap(object, new_map);
if (FLAG_trace_migration) {
object->PrintInstanceMigration(stdout, *original_map, object->map());
}
return true;
}
void JSObject::MigrateToNewProperty(Handle<JSObject> object,
Handle<Map> map,
Handle<Object> value) {
JSObject::MigrateToMap(object, map);
if (map->GetLastDescriptorDetails().type() != FIELD) return;
object->WriteToField(map->LastAdded(), *value);
}
void JSObject::WriteToField(int descriptor, Object* value) {
DisallowHeapAllocation no_gc;
DescriptorArray* desc = map()->instance_descriptors();
PropertyDetails details = desc->GetDetails(descriptor);
DCHECK(details.type() == FIELD);
FieldIndex index = FieldIndex::ForDescriptor(map(), descriptor);
if (details.representation().IsDouble()) {
// Nothing more to be done.
if (value->IsUninitialized()) return;
HeapNumber* box = HeapNumber::cast(RawFastPropertyAt(index));
DCHECK(box->IsMutableHeapNumber());
box->set_value(value->Number());
} else {
FastPropertyAtPut(index, value);
}
}
void JSObject::AddProperty(Handle<JSObject> object, Handle<Name> name,
Handle<Object> value,
PropertyAttributes attributes) {
LookupIterator it(object, name, LookupIterator::OWN_SKIP_INTERCEPTOR);
CHECK_NE(LookupIterator::ACCESS_CHECK, it.state());
#ifdef DEBUG
uint32_t index;
DCHECK(!object->IsJSProxy());
DCHECK(!name->AsArrayIndex(&index));
Maybe<PropertyAttributes> maybe = GetPropertyAttributes(&it);
DCHECK(maybe.has_value);
DCHECK(!it.IsFound());
DCHECK(object->map()->is_extensible() ||
name.is_identical_to(it.isolate()->factory()->hidden_string()));
#endif
AddDataProperty(&it, value, attributes, STRICT,
CERTAINLY_NOT_STORE_FROM_KEYED).Check();
}
// Reconfigures a property to a data property with attributes, even if it is not
// reconfigurable.
MaybeHandle<Object> JSObject::SetOwnPropertyIgnoreAttributes(
Handle<JSObject> object,
Handle<Name> name,
Handle<Object> value,
PropertyAttributes attributes,
ExecutableAccessorInfoHandling handling) {
DCHECK(!value->IsTheHole());
LookupIterator it(object, name, LookupIterator::OWN_SKIP_INTERCEPTOR);
bool is_observed = object->map()->is_observed() &&
*name != it.isolate()->heap()->hidden_string();
for (; it.IsFound(); it.Next()) {
switch (it.state()) {
case LookupIterator::INTERCEPTOR:
case LookupIterator::JSPROXY:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::ACCESS_CHECK:
if (!it.isolate()->MayNamedAccess(object, name, v8::ACCESS_SET)) {
return SetPropertyWithFailedAccessCheck(&it, value, SLOPPY);
}
break;
case LookupIterator::ACCESSOR: {
PropertyDetails details = it.property_details();
Handle<Object> old_value = it.isolate()->factory()->the_hole_value();
// Ensure the context isn't changed after calling into accessors.
AssertNoContextChange ncc(it.isolate());
Handle<Object> accessors = it.GetAccessors();
if (is_observed && accessors->IsAccessorInfo()) {
ASSIGN_RETURN_ON_EXCEPTION(
it.isolate(), old_value,
GetPropertyWithAccessor(it.GetReceiver(), it.name(),
it.GetHolder<JSObject>(), accessors),
Object);
}
// Special handling for ExecutableAccessorInfo, which behaves like a
// data property.
if (handling == DONT_FORCE_FIELD &&
accessors->IsExecutableAccessorInfo()) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
it.isolate(), result,
JSObject::SetPropertyWithAccessor(it.GetReceiver(), it.name(),
value, it.GetHolder<JSObject>(),
accessors, STRICT),
Object);
DCHECK(result->SameValue(*value));
if (details.attributes() == attributes) {
// Regular property update if the attributes match.
if (is_observed && !old_value->SameValue(*value)) {
// If we are setting the prototype of a function and are
// observed, don't send change records because the prototype
// handles that itself.
if (!object->IsJSFunction() ||
!Name::Equals(it.isolate()->factory()->prototype_string(),
name) ||
!Handle<JSFunction>::cast(object)->should_have_prototype()) {
EnqueueChangeRecord(object, "update", name, old_value);
}
}
return value;
}
// Reconfigure the accessor if attributes mismatch.
Handle<ExecutableAccessorInfo> new_data = Accessors::CloneAccessor(
it.isolate(), Handle<ExecutableAccessorInfo>::cast(accessors));
new_data->set_property_attributes(attributes);
// By clearing the setter we don't have to introduce a lookup to
// the setter, simply make it unavailable to reflect the
// attributes.
if (attributes & READ_ONLY) new_data->clear_setter();
SetPropertyCallback(object, name, new_data, attributes);
if (is_observed) {
if (old_value->SameValue(*value)) {
old_value = it.isolate()->factory()->the_hole_value();
}
EnqueueChangeRecord(object, "reconfigure", name, old_value);
}
return value;
}
it.ReconfigureDataProperty(value, attributes);
it.PrepareForDataProperty(value);
it.WriteDataValue(value);
if (is_observed) {
if (old_value->SameValue(*value)) {
old_value = it.isolate()->factory()->the_hole_value();
}
EnqueueChangeRecord(object, "reconfigure", name, old_value);
}
return value;
}
case LookupIterator::DATA: {
PropertyDetails details = it.property_details();
Handle<Object> old_value = it.isolate()->factory()->the_hole_value();
// Regular property update if the attributes match.
if (details.attributes() == attributes) {
return SetDataProperty(&it, value);
}
// Reconfigure the data property if the attributes mismatch.
if (is_observed) old_value = it.GetDataValue();
it.ReconfigureDataProperty(value, attributes);
it.PrepareForDataProperty(value);
it.WriteDataValue(value);
if (is_observed) {
if (old_value->SameValue(*value)) {
old_value = it.isolate()->factory()->the_hole_value();
}
EnqueueChangeRecord(object, "reconfigure", name, old_value);
}
return value;
}
}
}
return AddDataProperty(&it, value, attributes, STRICT,
CERTAINLY_NOT_STORE_FROM_KEYED);
}
Maybe<PropertyAttributes> JSObject::GetPropertyAttributesWithInterceptor(
Handle<JSObject> holder,
Handle<Object> receiver,
Handle<Name> name) {
// TODO(rossberg): Support symbols in the API.
if (name->IsSymbol()) return maybe(ABSENT);
Isolate* isolate = holder->GetIsolate();
HandleScope scope(isolate);
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc(isolate);
Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor());
PropertyCallbackArguments args(
isolate, interceptor->data(), *receiver, *holder);
if (!interceptor->query()->IsUndefined()) {
v8::NamedPropertyQueryCallback query =
v8::ToCData<v8::NamedPropertyQueryCallback>(interceptor->query());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-has", *holder, *name));
v8::Handle<v8::Integer> result =
args.Call(query, v8::Utils::ToLocal(Handle<String>::cast(name)));
if (!result.IsEmpty()) {
DCHECK(result->IsInt32());
return maybe(static_cast<PropertyAttributes>(result->Int32Value()));
}
} else if (!interceptor->getter()->IsUndefined()) {
v8::NamedPropertyGetterCallback getter =
v8::ToCData<v8::NamedPropertyGetterCallback>(interceptor->getter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-get-has", *holder, *name));
v8::Handle<v8::Value> result =
args.Call(getter, v8::Utils::ToLocal(Handle<String>::cast(name)));
if (!result.IsEmpty()) return maybe(DONT_ENUM);
}
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Maybe<PropertyAttributes>());
return maybe(ABSENT);
}
Maybe<PropertyAttributes> JSReceiver::GetOwnPropertyAttributes(
Handle<JSReceiver> object, Handle<Name> name) {
// Check whether the name is an array index.
uint32_t index = 0;
if (object->IsJSObject() && name->AsArrayIndex(&index)) {
return GetOwnElementAttribute(object, index);
}
LookupIterator it(object, name, LookupIterator::HIDDEN);
return GetPropertyAttributes(&it);
}
Maybe<PropertyAttributes> JSReceiver::GetPropertyAttributes(
LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::JSPROXY:
return JSProxy::GetPropertyAttributesWithHandler(
it->GetHolder<JSProxy>(), it->GetReceiver(), it->name());
case LookupIterator::INTERCEPTOR: {
Maybe<PropertyAttributes> result =
JSObject::GetPropertyAttributesWithInterceptor(
it->GetHolder<JSObject>(), it->GetReceiver(), it->name());
if (!result.has_value) return result;
if (result.value != ABSENT) return result;
break;
}
case LookupIterator::ACCESS_CHECK:
if (it->HasAccess(v8::ACCESS_HAS)) break;
return JSObject::GetPropertyAttributesWithFailedAccessCheck(it);
case LookupIterator::ACCESSOR:
case LookupIterator::DATA:
return maybe(it->property_details().attributes());
}
}
return maybe(ABSENT);
}
Maybe<PropertyAttributes> JSObject::GetElementAttributeWithReceiver(
Handle<JSObject> object, Handle<JSReceiver> receiver, uint32_t index,
bool check_prototype) {
Isolate* isolate = object->GetIsolate();
// Check access rights if needed.
if (object->IsAccessCheckNeeded()) {
if (!isolate->MayIndexedAccess(object, index, v8::ACCESS_HAS)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_HAS);
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Maybe<PropertyAttributes>());
return maybe(ABSENT);
}
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return maybe(ABSENT);
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return JSObject::GetElementAttributeWithReceiver(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), receiver,
index, check_prototype);
}
// Check for lookup interceptor except when bootstrapping.
if (object->HasIndexedInterceptor() && !isolate->bootstrapper()->IsActive()) {
return JSObject::GetElementAttributeWithInterceptor(
object, receiver, index, check_prototype);
}
return GetElementAttributeWithoutInterceptor(
object, receiver, index, check_prototype);
}
Maybe<PropertyAttributes> JSObject::GetElementAttributeWithInterceptor(
Handle<JSObject> object, Handle<JSReceiver> receiver, uint32_t index,
bool check_prototype) {
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc(isolate);
Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
PropertyCallbackArguments args(
isolate, interceptor->data(), *receiver, *object);
if (!interceptor->query()->IsUndefined()) {
v8::IndexedPropertyQueryCallback query =
v8::ToCData<v8::IndexedPropertyQueryCallback>(interceptor->query());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-has", *object, index));
v8::Handle<v8::Integer> result = args.Call(query, index);
if (!result.IsEmpty())
return maybe(static_cast<PropertyAttributes>(result->Int32Value()));
} else if (!interceptor->getter()->IsUndefined()) {
v8::IndexedPropertyGetterCallback getter =
v8::ToCData<v8::IndexedPropertyGetterCallback>(interceptor->getter());
LOG(isolate,
ApiIndexedPropertyAccess(
"interceptor-indexed-get-has", *object, index));
v8::Handle<v8::Value> result = args.Call(getter, index);
if (!result.IsEmpty()) return maybe(NONE);
}
return GetElementAttributeWithoutInterceptor(
object, receiver, index, check_prototype);
}
Maybe<PropertyAttributes> JSObject::GetElementAttributeWithoutInterceptor(
Handle<JSObject> object, Handle<JSReceiver> receiver, uint32_t index,
bool check_prototype) {
PropertyAttributes attr = object->GetElementsAccessor()->GetAttributes(
receiver, object, index);
if (attr != ABSENT) return maybe(attr);
// Handle [] on String objects.
if (object->IsStringObjectWithCharacterAt(index)) {
return maybe(static_cast<PropertyAttributes>(READ_ONLY | DONT_DELETE));
}
if (!check_prototype) return maybe(ABSENT);
PrototypeIterator iter(object->GetIsolate(), object);
if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
// We need to follow the spec and simulate a call to [[GetOwnProperty]].
return JSProxy::GetElementAttributeWithHandler(
Handle<JSProxy>::cast(PrototypeIterator::GetCurrent(iter)), receiver,
index);
}
if (iter.IsAtEnd()) return maybe(ABSENT);
return GetElementAttributeWithReceiver(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), receiver,
index, true);
}
Handle<NormalizedMapCache> NormalizedMapCache::New(Isolate* isolate) {
Handle<FixedArray> array(
isolate->factory()->NewFixedArray(kEntries, TENURED));
return Handle<NormalizedMapCache>::cast(array);
}
MaybeHandle<Map> NormalizedMapCache::Get(Handle<Map> fast_map,
PropertyNormalizationMode mode) {
DisallowHeapAllocation no_gc;
Object* value = FixedArray::get(GetIndex(fast_map));
if (!value->IsMap() ||
!Map::cast(value)->EquivalentToForNormalization(*fast_map, mode)) {
return MaybeHandle<Map>();
}
return handle(Map::cast(value));
}
void NormalizedMapCache::Set(Handle<Map> fast_map,
Handle<Map> normalized_map) {
DisallowHeapAllocation no_gc;
DCHECK(normalized_map->is_dictionary_map());
FixedArray::set(GetIndex(fast_map), *normalized_map);
}
void NormalizedMapCache::Clear() {
int entries = length();
for (int i = 0; i != entries; i++) {
set_undefined(i);
}
}
void HeapObject::UpdateMapCodeCache(Handle<HeapObject> object,
Handle<Name> name,
Handle<Code> code) {
Handle<Map> map(object->map());
Map::UpdateCodeCache(map, name, code);
}
void JSObject::NormalizeProperties(Handle<JSObject> object,
PropertyNormalizationMode mode,
int expected_additional_properties) {
if (!object->HasFastProperties()) return;
Handle<Map> map(object->map());
Handle<Map> new_map = Map::Normalize(map, mode);
MigrateFastToSlow(object, new_map, expected_additional_properties);
}
void JSObject::MigrateFastToSlow(Handle<JSObject> object,
Handle<Map> new_map,
int expected_additional_properties) {
// The global object is always normalized.
DCHECK(!object->IsGlobalObject());
// JSGlobalProxy must never be normalized
DCHECK(!object->IsJSGlobalProxy());
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
Handle<Map> map(object->map());
// Allocate new content.
int real_size = map->NumberOfOwnDescriptors();
int property_count = real_size;
if (expected_additional_properties > 0) {
property_count += expected_additional_properties;
} else {
property_count += 2; // Make space for two more properties.
}
Handle<NameDictionary> dictionary =
NameDictionary::New(isolate, property_count);
Handle<DescriptorArray> descs(map->instance_descriptors());
for (int i = 0; i < real_size; i++) {
PropertyDetails details = descs->GetDetails(i);
switch (details.type()) {
case CONSTANT: {
Handle<Name> key(descs->GetKey(i));
Handle<Object> value(descs->GetConstant(i), isolate);
PropertyDetails d = PropertyDetails(
details.attributes(), NORMAL, i + 1);
dictionary = NameDictionary::Add(dictionary, key, value, d);
break;
}
case FIELD: {
Handle<Name> key(descs->GetKey(i));
FieldIndex index = FieldIndex::ForDescriptor(*map, i);
Handle<Object> value(
object->RawFastPropertyAt(index), isolate);
if (details.representation().IsDouble()) {
DCHECK(value->IsMutableHeapNumber());
Handle<HeapNumber> old = Handle<HeapNumber>::cast(value);
value = isolate->factory()->NewHeapNumber(old->value());
}
PropertyDetails d =
PropertyDetails(details.attributes(), NORMAL, i + 1);
dictionary = NameDictionary::Add(dictionary, key, value, d);
break;
}
case CALLBACKS: {
Handle<Name> key(descs->GetKey(i));
Handle<Object> value(descs->GetCallbacksObject(i), isolate);
PropertyDetails d = PropertyDetails(
details.attributes(), CALLBACKS, i + 1);
dictionary = NameDictionary::Add(dictionary, key, value, d);
break;
}
case NORMAL:
UNREACHABLE();
break;
}
}
// Copy the next enumeration index from instance descriptor.
dictionary->SetNextEnumerationIndex(real_size + 1);
// From here on we cannot fail and we shouldn't GC anymore.
DisallowHeapAllocation no_allocation;
// Resize the object in the heap if necessary.
int new_instance_size = new_map->instance_size();
int instance_size_delta = map->instance_size() - new_instance_size;
DCHECK(instance_size_delta >= 0);
if (instance_size_delta > 0) {
Heap* heap = isolate->heap();
heap->CreateFillerObjectAt(object->address() + new_instance_size,
instance_size_delta);
heap->AdjustLiveBytes(object->address(), -instance_size_delta,
Heap::FROM_MUTATOR);
}
// We are storing the new map using release store after creating a filler for
// the left-over space to avoid races with the sweeper thread.
object->synchronized_set_map(*new_map);
object->set_properties(*dictionary);
isolate->counters()->props_to_dictionary()->Increment();
#ifdef DEBUG
if (FLAG_trace_normalization) {
OFStream os(stdout);
os << "Object properties have been normalized:\n";
object->Print(os);
}
#endif
}
void JSObject::MigrateSlowToFast(Handle<JSObject> object,
int unused_property_fields) {
if (object->HasFastProperties()) return;
DCHECK(!object->IsGlobalObject());
Isolate* isolate = object->GetIsolate();
Factory* factory = isolate->factory();
Handle<NameDictionary> dictionary(object->property_dictionary());
// Make sure we preserve dictionary representation if there are too many
// descriptors.
int number_of_elements = dictionary->NumberOfElements();
if (number_of_elements > kMaxNumberOfDescriptors) return;
if (number_of_elements != dictionary->NextEnumerationIndex()) {
NameDictionary::DoGenerateNewEnumerationIndices(dictionary);
}
int instance_descriptor_length = 0;
int number_of_fields = 0;
// Compute the length of the instance descriptor.
int capacity = dictionary->Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = dictionary->KeyAt(i);
if (dictionary->IsKey(k)) {
Object* value = dictionary->ValueAt(i);
PropertyType type = dictionary->DetailsAt(i).type();
DCHECK(type != FIELD);
instance_descriptor_length++;
if (type == NORMAL && !value->IsJSFunction()) {
number_of_fields += 1;
}
}
}
int inobject_props = object->map()->inobject_properties();
// Allocate new map.
Handle<Map> new_map = Map::CopyDropDescriptors(handle(object->map()));
new_map->set_dictionary_map(false);
if (instance_descriptor_length == 0) {
DisallowHeapAllocation no_gc;
DCHECK_LE(unused_property_fields, inobject_props);
// Transform the object.
new_map->set_unused_property_fields(inobject_props);
object->synchronized_set_map(*new_map);
object->set_properties(isolate->heap()->empty_fixed_array());
// Check that it really works.
DCHECK(object->HasFastProperties());
return;
}
// Allocate the instance descriptor.
Handle<DescriptorArray> descriptors = DescriptorArray::Allocate(
isolate, instance_descriptor_length);
int number_of_allocated_fields =
number_of_fields + unused_property_fields - inobject_props;
if (number_of_allocated_fields < 0) {
// There is enough inobject space for all fields (including unused).
number_of_allocated_fields = 0;
unused_property_fields = inobject_props - number_of_fields;
}
// Allocate the fixed array for the fields.
Handle<FixedArray> fields = factory->NewFixedArray(
number_of_allocated_fields);
// Fill in the instance descriptor and the fields.
int current_offset = 0;
for (int i = 0; i < capacity; i++) {
Object* k = dictionary->KeyAt(i);
if (dictionary->IsKey(k)) {
Object* value = dictionary->ValueAt(i);
Handle<Name> key;
if (k->IsSymbol()) {
key = handle(Symbol::cast(k));
} else {
// Ensure the key is a unique name before writing into the
// instance descriptor.
key = factory->InternalizeString(handle(String::cast(k)));
}
PropertyDetails details = dictionary->DetailsAt(i);
int enumeration_index = details.dictionary_index();
PropertyType type = details.type();
if (value->IsJSFunction()) {
ConstantDescriptor d(key,
handle(value, isolate),
details.attributes());
descriptors->Set(enumeration_index - 1, &d);
} else if (type == NORMAL) {
if (current_offset < inobject_props) {
object->InObjectPropertyAtPut(current_offset,
value,
UPDATE_WRITE_BARRIER);
} else {
int offset = current_offset - inobject_props;
fields->set(offset, value);
}
FieldDescriptor d(key,
current_offset++,
details.attributes(),
// TODO(verwaest): value->OptimalRepresentation();
Representation::Tagged());
descriptors->Set(enumeration_index - 1, &d);
} else if (type == CALLBACKS) {
CallbacksDescriptor d(key,
handle(value, isolate),
details.attributes());
descriptors->Set(enumeration_index - 1, &d);
} else {
UNREACHABLE();
}
}
}
DCHECK(current_offset == number_of_fields);
descriptors->Sort();
DisallowHeapAllocation no_gc;
new_map->InitializeDescriptors(*descriptors);
new_map->set_unused_property_fields(unused_property_fields);
// Transform the object.
object->synchronized_set_map(*new_map);
object->set_properties(*fields);
DCHECK(object->IsJSObject());
// Check that it really works.
DCHECK(object->HasFastProperties());
}
void JSObject::ResetElements(Handle<JSObject> object) {
Isolate* isolate = object->GetIsolate();
CHECK(object->map() != isolate->heap()->sloppy_arguments_elements_map());
if (object->map()->has_dictionary_elements()) {
Handle<SeededNumberDictionary> new_elements =
SeededNumberDictionary::New(isolate, 0);
object->set_elements(*new_elements);
} else {
object->set_elements(object->map()->GetInitialElements());
}
}
static Handle<SeededNumberDictionary> CopyFastElementsToDictionary(
Handle<FixedArrayBase> array,
int length,
Handle<SeededNumberDictionary> dictionary) {
Isolate* isolate = array->GetIsolate();
Factory* factory = isolate->factory();
bool has_double_elements = array->IsFixedDoubleArray();
for (int i = 0; i < length; i++) {
Handle<Object> value;
if (has_double_elements) {
Handle<FixedDoubleArray> double_array =
Handle<FixedDoubleArray>::cast(array);
if (double_array->is_the_hole(i)) {
value = factory->the_hole_value();
} else {
value = factory->NewHeapNumber(double_array->get_scalar(i));
}
} else {
value = handle(Handle<FixedArray>::cast(array)->get(i), isolate);
}
if (!value->IsTheHole()) {
PropertyDetails details = PropertyDetails(NONE, NORMAL, 0);
dictionary =
SeededNumberDictionary::AddNumberEntry(dictionary, i, value, details);
}
}
return dictionary;
}
Handle<SeededNumberDictionary> JSObject::NormalizeElements(
Handle<JSObject> object) {
DCHECK(!object->HasExternalArrayElements() &&
!object->HasFixedTypedArrayElements());
Isolate* isolate = object->GetIsolate();
// Find the backing store.
Handle<FixedArrayBase> array(FixedArrayBase::cast(object->elements()));
bool is_arguments =
(array->map() == isolate->heap()->sloppy_arguments_elements_map());
if (is_arguments) {
array = handle(FixedArrayBase::cast(
Handle<FixedArray>::cast(array)->get(1)));
}
if (array->IsDictionary()) return Handle<SeededNumberDictionary>::cast(array);
DCHECK(object->HasFastSmiOrObjectElements() ||
object->HasFastDoubleElements() ||
object->HasFastArgumentsElements());
// Compute the effective length and allocate a new backing store.
int length = object->IsJSArray()
? Smi::cast(Handle<JSArray>::cast(object)->length())->value()
: array->length();
int old_capacity = 0;
int used_elements = 0;
object->GetElementsCapacityAndUsage(&old_capacity, &used_elements);
Handle<SeededNumberDictionary> dictionary =
SeededNumberDictionary::New(isolate, used_elements);
dictionary = CopyFastElementsToDictionary(array, length, dictionary);
// Switch to using the dictionary as the backing storage for elements.
if (is_arguments) {
FixedArray::cast(object->elements())->set(1, *dictionary);
} else {
// Set the new map first to satify the elements type assert in
// set_elements().
Handle<Map> new_map =
JSObject::GetElementsTransitionMap(object, DICTIONARY_ELEMENTS);
JSObject::MigrateToMap(object, new_map);
object->set_elements(*dictionary);
}
isolate->counters()->elements_to_dictionary()->Increment();
#ifdef DEBUG
if (FLAG_trace_normalization) {
OFStream os(stdout);
os << "Object elements have been normalized:\n";
object->Print(os);
}
#endif
DCHECK(object->HasDictionaryElements() ||
object->HasDictionaryArgumentsElements());
return dictionary;
}
static Smi* GenerateIdentityHash(Isolate* isolate) {
int hash_value;
int attempts = 0;
do {
// Generate a random 32-bit hash value but limit range to fit
// within a smi.
hash_value = isolate->random_number_generator()->NextInt() & Smi::kMaxValue;
attempts++;
} while (hash_value == 0 && attempts < 30);
hash_value = hash_value != 0 ? hash_value : 1; // never return 0
return Smi::FromInt(hash_value);
}
void JSObject::SetIdentityHash(Handle<JSObject> object, Handle<Smi> hash) {
DCHECK(!object->IsJSGlobalProxy());
Isolate* isolate = object->GetIsolate();
SetHiddenProperty(object, isolate->factory()->identity_hash_string(), hash);
}
template<typename ProxyType>
static Handle<Smi> GetOrCreateIdentityHashHelper(Handle<ProxyType> proxy) {
Isolate* isolate = proxy->GetIsolate();
Handle<Object> maybe_hash(proxy->hash(), isolate);
if (maybe_hash->IsSmi()) return Handle<Smi>::cast(maybe_hash);
Handle<Smi> hash(GenerateIdentityHash(isolate), isolate);
proxy->set_hash(*hash);
return hash;
}
Object* JSObject::GetIdentityHash() {
DisallowHeapAllocation no_gc;
Isolate* isolate = GetIsolate();
if (IsJSGlobalProxy()) {
return JSGlobalProxy::cast(this)->hash();
}
Object* stored_value =
GetHiddenProperty(isolate->factory()->identity_hash_string());
return stored_value->IsSmi()
? stored_value
: isolate->heap()->undefined_value();
}
Handle<Smi> JSObject::GetOrCreateIdentityHash(Handle<JSObject> object) {
if (object->IsJSGlobalProxy()) {
return GetOrCreateIdentityHashHelper(Handle<JSGlobalProxy>::cast(object));
}
Isolate* isolate = object->GetIsolate();
Handle<Object> maybe_hash(object->GetIdentityHash(), isolate);
if (maybe_hash->IsSmi()) return Handle<Smi>::cast(maybe_hash);
Handle<Smi> hash(GenerateIdentityHash(isolate), isolate);
SetHiddenProperty(object, isolate->factory()->identity_hash_string(), hash);
return hash;
}
Object* JSProxy::GetIdentityHash() {
return this->hash();
}
Handle<Smi> JSProxy::GetOrCreateIdentityHash(Handle<JSProxy> proxy) {
return GetOrCreateIdentityHashHelper(proxy);
}
Object* JSObject::GetHiddenProperty(Handle<Name> key) {
DisallowHeapAllocation no_gc;
DCHECK(key->IsUniqueName());
if (IsJSGlobalProxy()) {
// JSGlobalProxies store their hash internally.
DCHECK(*key != GetHeap()->identity_hash_string());
// For a proxy, use the prototype as target object.
PrototypeIterator iter(GetIsolate(), this);
// If the proxy is detached, return undefined.
if (iter.IsAtEnd()) return GetHeap()->the_hole_value();
DCHECK(iter.GetCurrent()->IsJSGlobalObject());
return JSObject::cast(iter.GetCurrent())->GetHiddenProperty(key);
}
DCHECK(!IsJSGlobalProxy());
Object* inline_value = GetHiddenPropertiesHashTable();
if (inline_value->IsSmi()) {
// Handle inline-stored identity hash.
if (*key == GetHeap()->identity_hash_string()) {
return inline_value;
} else {
return GetHeap()->the_hole_value();
}
}
if (inline_value->IsUndefined()) return GetHeap()->the_hole_value();
ObjectHashTable* hashtable = ObjectHashTable::cast(inline_value);
Object* entry = hashtable->Lookup(key);
return entry;
}
Handle<Object> JSObject::SetHiddenProperty(Handle<JSObject> object,
Handle<Name> key,
Handle<Object> value) {
Isolate* isolate = object->GetIsolate();
DCHECK(key->IsUniqueName());
if (object->IsJSGlobalProxy()) {
// JSGlobalProxies store their hash internally.
DCHECK(*key != *isolate->factory()->identity_hash_string());
// For a proxy, use the prototype as target object.
PrototypeIterator iter(isolate, object);
// If the proxy is detached, return undefined.
if (iter.IsAtEnd()) return isolate->factory()->undefined_value();
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return SetHiddenProperty(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), key,
value);
}
DCHECK(!object->IsJSGlobalProxy());
Handle<Object> inline_value(object->GetHiddenPropertiesHashTable(), isolate);
// If there is no backing store yet, store the identity hash inline.
if (value->IsSmi() &&
*key == *isolate->factory()->identity_hash_string() &&
(inline_value->IsUndefined() || inline_value->IsSmi())) {
return JSObject::SetHiddenPropertiesHashTable(object, value);
}
Handle<ObjectHashTable> hashtable =
GetOrCreateHiddenPropertiesHashtable(object);
// If it was found, check if the key is already in the dictionary.
Handle<ObjectHashTable> new_table = ObjectHashTable::Put(hashtable, key,
value);
if (*new_table != *hashtable) {
// If adding the key expanded the dictionary (i.e., Add returned a new
// dictionary), store it back to the object.
SetHiddenPropertiesHashTable(object, new_table);
}
// Return this to mark success.
return object;
}
void JSObject::DeleteHiddenProperty(Handle<JSObject> object, Handle<Name> key) {
Isolate* isolate = object->GetIsolate();
DCHECK(key->IsUniqueName());
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return;
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return DeleteHiddenProperty(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), key);
}
Object* inline_value = object->GetHiddenPropertiesHashTable();
// We never delete (inline-stored) identity hashes.
DCHECK(*key != *isolate->factory()->identity_hash_string());
if (inline_value->IsUndefined() || inline_value->IsSmi()) return;
Handle<ObjectHashTable> hashtable(ObjectHashTable::cast(inline_value));
bool was_present = false;
ObjectHashTable::Remove(hashtable, key, &was_present);
}
bool JSObject::HasHiddenProperties(Handle<JSObject> object) {
Handle<Name> hidden = object->GetIsolate()->factory()->hidden_string();
LookupIterator it(object, hidden, LookupIterator::OWN_SKIP_INTERCEPTOR);
Maybe<PropertyAttributes> maybe = GetPropertyAttributes(&it);
// Cannot get an exception since the hidden_string isn't accessible to JS.
DCHECK(maybe.has_value);
return maybe.value != ABSENT;
}
Object* JSObject::GetHiddenPropertiesHashTable() {
DCHECK(!IsJSGlobalProxy());
if (HasFastProperties()) {
// If the object has fast properties, check whether the first slot
// in the descriptor array matches the hidden string. Since the
// hidden strings hash code is zero (and no other name has hash
// code zero) it will always occupy the first entry if present.
DescriptorArray* descriptors = this->map()->instance_descriptors();
if (descriptors->number_of_descriptors() > 0) {
int sorted_index = descriptors->GetSortedKeyIndex(0);
if (descriptors->GetKey(sorted_index) == GetHeap()->hidden_string() &&
sorted_index < map()->NumberOfOwnDescriptors()) {
DCHECK(descriptors->GetType(sorted_index) == FIELD);
DCHECK(descriptors->GetDetails(sorted_index).representation().
IsCompatibleForLoad(Representation::Tagged()));
FieldIndex index = FieldIndex::ForDescriptor(this->map(),
sorted_index);
return this->RawFastPropertyAt(index);
} else {
return GetHeap()->undefined_value();
}
} else {
return GetHeap()->undefined_value();
}
} else {
Isolate* isolate = GetIsolate();
LookupIterator it(handle(this), isolate->factory()->hidden_string(),
LookupIterator::OWN_SKIP_INTERCEPTOR);
// Access check is always skipped for the hidden string anyways.
return *GetDataProperty(&it);
}
}
Handle<ObjectHashTable> JSObject::GetOrCreateHiddenPropertiesHashtable(
Handle<JSObject> object) {
Isolate* isolate = object->GetIsolate();
static const int kInitialCapacity = 4;
Handle<Object> inline_value(object->GetHiddenPropertiesHashTable(), isolate);
if (inline_value->IsHashTable()) {
return Handle<ObjectHashTable>::cast(inline_value);
}
Handle<ObjectHashTable> hashtable = ObjectHashTable::New(
isolate, kInitialCapacity, USE_CUSTOM_MINIMUM_CAPACITY);
if (inline_value->IsSmi()) {
// We were storing the identity hash inline and now allocated an actual
// dictionary. Put the identity hash into the new dictionary.
hashtable = ObjectHashTable::Put(hashtable,
isolate->factory()->identity_hash_string(),
inline_value);
}
SetHiddenPropertiesHashTable(object, hashtable);
return hashtable;
}
Handle<Object> JSObject::SetHiddenPropertiesHashTable(Handle<JSObject> object,
Handle<Object> value) {
DCHECK(!object->IsJSGlobalProxy());
Isolate* isolate = object->GetIsolate();
Handle<Name> name = isolate->factory()->hidden_string();
SetOwnPropertyIgnoreAttributes(object, name, value, DONT_ENUM).Assert();
return object;
}
MaybeHandle<Object> JSObject::DeletePropertyWithInterceptor(
Handle<JSObject> holder, Handle<JSObject> receiver, Handle<Name> name) {
Isolate* isolate = holder->GetIsolate();
// TODO(rossberg): Support symbols in the API.
if (name->IsSymbol()) return MaybeHandle<Object>();
Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor());
if (interceptor->deleter()->IsUndefined()) return MaybeHandle<Object>();
v8::NamedPropertyDeleterCallback deleter =
v8::ToCData<v8::NamedPropertyDeleterCallback>(interceptor->deleter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-delete", *holder, *name));
PropertyCallbackArguments args(isolate, interceptor->data(), *receiver,
*holder);
v8::Handle<v8::Boolean> result =
args.Call(deleter, v8::Utils::ToLocal(Handle<String>::cast(name)));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (result.IsEmpty()) return MaybeHandle<Object>();
DCHECK(result->IsBoolean());
Handle<Object> result_internal = v8::Utils::OpenHandle(*result);
result_internal->VerifyApiCallResultType();
// Rebox CustomArguments::kReturnValueOffset before returning.
return handle(*result_internal, isolate);
}
MaybeHandle<Object> JSObject::DeleteElementWithInterceptor(
Handle<JSObject> object,
uint32_t index) {
Isolate* isolate = object->GetIsolate();
Factory* factory = isolate->factory();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc(isolate);
Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
if (interceptor->deleter()->IsUndefined()) return factory->false_value();
v8::IndexedPropertyDeleterCallback deleter =
v8::ToCData<v8::IndexedPropertyDeleterCallback>(interceptor->deleter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-delete", *object, index));
PropertyCallbackArguments args(
isolate, interceptor->data(), *object, *object);
v8::Handle<v8::Boolean> result = args.Call(deleter, index);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (!result.IsEmpty()) {
DCHECK(result->IsBoolean());
Handle<Object> result_internal = v8::Utils::OpenHandle(*result);
result_internal->VerifyApiCallResultType();
// Rebox CustomArguments::kReturnValueOffset before returning.
return handle(*result_internal, isolate);
}
MaybeHandle<Object> delete_result = object->GetElementsAccessor()->Delete(
object, index, NORMAL_DELETION);
return delete_result;
}
MaybeHandle<Object> JSObject::DeleteElement(Handle<JSObject> object,
uint32_t index,
DeleteMode mode) {
Isolate* isolate = object->GetIsolate();
Factory* factory = isolate->factory();
// Check access rights if needed.
if (object->IsAccessCheckNeeded() &&
!isolate->MayIndexedAccess(object, index, v8::ACCESS_DELETE)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_DELETE);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return factory->false_value();
}
if (object->IsStringObjectWithCharacterAt(index)) {
if (mode == STRICT_DELETION) {
// Deleting a non-configurable property in strict mode.
Handle<Object> name = factory->NewNumberFromUint(index);
Handle<Object> args[2] = { name, object };
THROW_NEW_ERROR(isolate, NewTypeError("strict_delete_property",
HandleVector(args, 2)),
Object);
}
return factory->false_value();
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return factory->false_value();
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return DeleteElement(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), index,
mode);
}
Handle<Object> old_value;
bool should_enqueue_change_record = false;
if (object->map()->is_observed()) {
Maybe<bool> maybe = HasOwnElement(object, index);
if (!maybe.has_value) return MaybeHandle<Object>();
should_enqueue_change_record = maybe.value;
if (should_enqueue_change_record) {
if (!GetOwnElementAccessorPair(object, index).is_null()) {
old_value = Handle<Object>::cast(factory->the_hole_value());
} else {
old_value = Object::GetElement(
isolate, object, index).ToHandleChecked();
}
}
}
// Skip interceptor if forcing deletion.
MaybeHandle<Object> maybe_result;
if (object->HasIndexedInterceptor() && mode != FORCE_DELETION) {
maybe_result = DeleteElementWithInterceptor(object, index);
} else {
maybe_result = object->GetElementsAccessor()->Delete(object, index, mode);
}
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(isolate, result, maybe_result, Object);
if (should_enqueue_change_record) {
Maybe<bool> maybe = HasOwnElement(object, index);
if (!maybe.has_value) return MaybeHandle<Object>();
if (!maybe.value) {
Handle<String> name = factory->Uint32ToString(index);
EnqueueChangeRecord(object, "delete", name, old_value);
}
}
return result;
}
MaybeHandle<Object> JSObject::DeleteProperty(Handle<JSObject> object,
Handle<Name> name,
DeleteMode delete_mode) {
// ECMA-262, 3rd, 8.6.2.5
DCHECK(name->IsName());
uint32_t index = 0;
if (name->AsArrayIndex(&index)) {
return DeleteElement(object, index, delete_mode);
}
// Skip interceptors on FORCE_DELETION.
LookupIterator::Configuration config =
delete_mode == FORCE_DELETION ? LookupIterator::HIDDEN_SKIP_INTERCEPTOR
: LookupIterator::HIDDEN;
LookupIterator it(object, name, config);
bool is_observed = object->map()->is_observed() &&
*name != it.isolate()->heap()->hidden_string();
Handle<Object> old_value = it.isolate()->factory()->the_hole_value();
for (; it.IsFound(); it.Next()) {
switch (it.state()) {
case LookupIterator::JSPROXY:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::ACCESS_CHECK:
if (it.HasAccess(v8::ACCESS_DELETE)) break;
it.isolate()->ReportFailedAccessCheck(it.GetHolder<JSObject>(),
v8::ACCESS_DELETE);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(it.isolate(), Object);
return it.isolate()->factory()->false_value();
case LookupIterator::INTERCEPTOR: {
MaybeHandle<Object> maybe_result =
JSObject::DeletePropertyWithInterceptor(it.GetHolder<JSObject>(),
object, it.name());
// Delete with interceptor succeeded. Return result.
if (!maybe_result.is_null()) return maybe_result;
// An exception was thrown in the interceptor. Propagate.
if (it.isolate()->has_pending_exception()) return maybe_result;
break;
}
case LookupIterator::DATA:
if (is_observed) {
old_value = it.GetDataValue();
}
// Fall through.
case LookupIterator::ACCESSOR: {
if (delete_mode != FORCE_DELETION && !it.IsConfigurable()) {
// Fail if the property is not configurable.
if (delete_mode == STRICT_DELETION) {
Handle<Object> args[2] = {name, object};
THROW_NEW_ERROR(it.isolate(),
NewTypeError("strict_delete_property",
HandleVector(args, arraysize(args))),
Object);
}
return it.isolate()->factory()->false_value();
}
PropertyNormalizationMode mode = object->map()->is_prototype_map()
? KEEP_INOBJECT_PROPERTIES
: CLEAR_INOBJECT_PROPERTIES;
Handle<JSObject> holder = it.GetHolder<JSObject>();
// TODO(verwaest): Remove this temporary compatibility hack when blink
// tests are updated.
if (!holder.is_identical_to(object) &&
!(object->IsJSGlobalProxy() && holder->IsJSGlobalObject())) {
return it.isolate()->factory()->true_value();
}
NormalizeProperties(holder, mode, 0);
Handle<Object> result =
DeleteNormalizedProperty(holder, name, delete_mode);
ReoptimizeIfPrototype(holder);
if (is_observed) {
EnqueueChangeRecord(object, "delete", name, old_value);
}
return result;
}
}
}
return it.isolate()->factory()->true_value();
}
MaybeHandle<Object> JSReceiver::DeleteElement(Handle<JSReceiver> object,
uint32_t index,
DeleteMode mode) {
if (object->IsJSProxy()) {
return JSProxy::DeleteElementWithHandler(
Handle<JSProxy>::cast(object), index, mode);
}
return JSObject::DeleteElement(Handle<JSObject>::cast(object), index, mode);
}
MaybeHandle<Object> JSReceiver::DeleteProperty(Handle<JSReceiver> object,
Handle<Name> name,
DeleteMode mode) {
if (object->IsJSProxy()) {
return JSProxy::DeletePropertyWithHandler(
Handle<JSProxy>::cast(object), name, mode);
}
return JSObject::DeleteProperty(Handle<JSObject>::cast(object), name, mode);
}
bool JSObject::ReferencesObjectFromElements(FixedArray* elements,
ElementsKind kind,
Object* object) {
DCHECK(IsFastObjectElementsKind(kind) ||
kind == DICTIONARY_ELEMENTS);
if (IsFastObjectElementsKind(kind)) {
int length = IsJSArray()
? Smi::cast(JSArray::cast(this)->length())->value()
: elements->length();
for (int i = 0; i < length; ++i) {
Object* element = elements->get(i);
if (!element->IsTheHole() && element == object) return true;
}
} else {
Object* key =
SeededNumberDictionary::cast(elements)->SlowReverseLookup(object);
if (!key->IsUndefined()) return true;
}
return false;
}
// Check whether this object references another object.
bool JSObject::ReferencesObject(Object* obj) {
Map* map_of_this = map();
Heap* heap = GetHeap();
DisallowHeapAllocation no_allocation;
// Is the object the constructor for this object?
if (map_of_this->constructor() == obj) {
return true;
}
// Is the object the prototype for this object?
if (map_of_this->prototype() == obj) {
return true;
}
// Check if the object is among the named properties.
Object* key = SlowReverseLookup(obj);
if (!key->IsUndefined()) {
return true;
}
// Check if the object is among the indexed properties.
ElementsKind kind = GetElementsKind();
switch (kind) {
// Raw pixels and external arrays do not reference other
// objects.
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
break;
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS:
break;
case FAST_SMI_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
break;
case FAST_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
case DICTIONARY_ELEMENTS: {
FixedArray* elements = FixedArray::cast(this->elements());
if (ReferencesObjectFromElements(elements, kind, obj)) return true;
break;
}
case SLOPPY_ARGUMENTS_ELEMENTS: {
FixedArray* parameter_map = FixedArray::cast(elements());
// Check the mapped parameters.
int length = parameter_map->length();
for (int i = 2; i < length; ++i) {
Object* value = parameter_map->get(i);
if (!value->IsTheHole() && value == obj) return true;
}
// Check the arguments.
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
kind = arguments->IsDictionary() ? DICTIONARY_ELEMENTS :
FAST_HOLEY_ELEMENTS;
if (ReferencesObjectFromElements(arguments, kind, obj)) return true;
break;
}
}
// For functions check the context.
if (IsJSFunction()) {
// Get the constructor function for arguments array.
Map* arguments_map =
heap->isolate()->context()->native_context()->sloppy_arguments_map();
JSFunction* arguments_function =
JSFunction::cast(arguments_map->constructor());
// Get the context and don't check if it is the native context.
JSFunction* f = JSFunction::cast(this);
Context* context = f->context();
if (context->IsNativeContext()) {
return false;
}
// Check the non-special context slots.
for (int i = Context::MIN_CONTEXT_SLOTS; i < context->length(); i++) {
// Only check JS objects.
if (context->get(i)->IsJSObject()) {
JSObject* ctxobj = JSObject::cast(context->get(i));
// If it is an arguments array check the content.
if (ctxobj->map()->constructor() == arguments_function) {
if (ctxobj->ReferencesObject(obj)) {
return true;
}
} else if (ctxobj == obj) {
return true;
}
}
}
// Check the context extension (if any) if it can have references.
if (context->has_extension() && !context->IsCatchContext()) {
// With harmony scoping, a JSFunction may have a global context.
// TODO(mvstanton): walk into the ScopeInfo.
if (FLAG_harmony_scoping && context->IsGlobalContext()) {
return false;
}
return JSObject::cast(context->extension())->ReferencesObject(obj);
}
}
// No references to object.
return false;
}
MaybeHandle<Object> JSObject::PreventExtensions(Handle<JSObject> object) {
Isolate* isolate = object->GetIsolate();
if (!object->map()->is_extensible()) return object;
if (object->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(
object, isolate->factory()->undefined_value(), v8::ACCESS_KEYS)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_KEYS);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->false_value();
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return object;
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return PreventExtensions(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)));
}
// It's not possible to seal objects with external array elements
if (object->HasExternalArrayElements() ||
object->HasFixedTypedArrayElements()) {
THROW_NEW_ERROR(isolate,
NewTypeError("cant_prevent_ext_external_array_elements",
HandleVector(&object, 1)),
Object);
}
// If there are fast elements we normalize.
Handle<SeededNumberDictionary> dictionary = NormalizeElements(object);
DCHECK(object->HasDictionaryElements() ||
object->HasDictionaryArgumentsElements());
// Make sure that we never go back to fast case.
dictionary->set_requires_slow_elements();
// Do a map transition, other objects with this map may still
// be extensible.
// TODO(adamk): Extend the NormalizedMapCache to handle non-extensible maps.
Handle<Map> new_map = Map::Copy(handle(object->map()));
new_map->set_is_extensible(false);
JSObject::MigrateToMap(object, new_map);
DCHECK(!object->map()->is_extensible());
if (object->map()->is_observed()) {
EnqueueChangeRecord(object, "preventExtensions", Handle<Name>(),
isolate->factory()->the_hole_value());
}
return object;
}
template<typename Dictionary>
static void FreezeDictionary(Dictionary* dictionary) {
int capacity = dictionary->Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = dictionary->KeyAt(i);
if (dictionary->IsKey(k) &&
!(k->IsSymbol() && Symbol::cast(k)->is_private())) {
PropertyDetails details = dictionary->DetailsAt(i);
int attrs = DONT_DELETE;
// READ_ONLY is an invalid attribute for JS setters/getters.
if (details.type() == CALLBACKS) {
Object* v = dictionary->ValueAt(i);
if (v->IsPropertyCell()) v = PropertyCell::cast(v)->value();
if (!v->IsAccessorPair()) attrs |= READ_ONLY;
} else {
attrs |= READ_ONLY;
}
details = details.CopyAddAttributes(
static_cast<PropertyAttributes>(attrs));
dictionary->DetailsAtPut(i, details);
}
}
}
MaybeHandle<Object> JSObject::Freeze(Handle<JSObject> object) {
// Freezing sloppy arguments should be handled elsewhere.
DCHECK(!object->HasSloppyArgumentsElements());
DCHECK(!object->map()->is_observed());
if (object->map()->is_frozen()) return object;
Isolate* isolate = object->GetIsolate();
if (object->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(
object, isolate->factory()->undefined_value(), v8::ACCESS_KEYS)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_KEYS);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->false_value();
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return object;
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return Freeze(Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)));
}
// It's not possible to freeze objects with external array elements
if (object->HasExternalArrayElements() ||
object->HasFixedTypedArrayElements()) {
THROW_NEW_ERROR(isolate,
NewTypeError("cant_prevent_ext_external_array_elements",
HandleVector(&object, 1)),
Object);
}
Handle<SeededNumberDictionary> new_element_dictionary;
if (!object->elements()->IsDictionary()) {
int length = object->IsJSArray()
? Smi::cast(Handle<JSArray>::cast(object)->length())->value()
: object->elements()->length();
if (length > 0) {
int capacity = 0;
int used = 0;
object->GetElementsCapacityAndUsage(&capacity, &used);
new_element_dictionary = SeededNumberDictionary::New(isolate, used);
// Move elements to a dictionary; avoid calling NormalizeElements to avoid
// unnecessary transitions.
new_element_dictionary = CopyFastElementsToDictionary(
handle(object->elements()), length, new_element_dictionary);
} else {
// No existing elements, use a pre-allocated empty backing store
new_element_dictionary =
isolate->factory()->empty_slow_element_dictionary();
}
}
Handle<Map> old_map(object->map(), isolate);
int transition_index = old_map->SearchTransition(
isolate->heap()->frozen_symbol());
if (transition_index != TransitionArray::kNotFound) {
Handle<Map> transition_map(old_map->GetTransition(transition_index));
DCHECK(transition_map->has_dictionary_elements());
DCHECK(transition_map->is_frozen());
DCHECK(!transition_map->is_extensible());
JSObject::MigrateToMap(object, transition_map);
} else if (object->HasFastProperties() && old_map->CanHaveMoreTransitions()) {
// Create a new descriptor array with fully-frozen properties
Handle<Map> new_map = Map::CopyForFreeze(old_map);
JSObject::MigrateToMap(object, new_map);
} else {
DCHECK(old_map->is_dictionary_map() || !old_map->is_prototype_map());
// Slow path: need to normalize properties for safety
NormalizeProperties(object, CLEAR_INOBJECT_PROPERTIES, 0);
// Create a new map, since other objects with this map may be extensible.
// TODO(adamk): Extend the NormalizedMapCache to handle non-extensible maps.
Handle<Map> new_map = Map::Copy(handle(object->map()));
new_map->freeze();
new_map->set_is_extensible(false);
new_map->set_elements_kind(DICTIONARY_ELEMENTS);
JSObject::MigrateToMap(object, new_map);
// Freeze dictionary-mode properties
FreezeDictionary(object->property_dictionary());
}
DCHECK(object->map()->has_dictionary_elements());
if (!new_element_dictionary.is_null()) {
object->set_elements(*new_element_dictionary);
}
if (object->elements() != isolate->heap()->empty_slow_element_dictionary()) {
SeededNumberDictionary* dictionary = object->element_dictionary();
// Make sure we never go back to the fast case
dictionary->set_requires_slow_elements();
// Freeze all elements in the dictionary
FreezeDictionary(dictionary);
}
return object;
}
void JSObject::SetObserved(Handle<JSObject> object) {
DCHECK(!object->IsJSGlobalProxy());
DCHECK(!object->IsJSGlobalObject());
Isolate* isolate = object->GetIsolate();
Handle<Map> new_map;
Handle<Map> old_map(object->map(), isolate);
DCHECK(!old_map->is_observed());
int transition_index = old_map->SearchTransition(
isolate->heap()->observed_symbol());
if (transition_index != TransitionArray::kNotFound) {
new_map = handle(old_map->GetTransition(transition_index), isolate);
DCHECK(new_map->is_observed());
} else if (object->HasFastProperties() && old_map->CanHaveMoreTransitions()) {
new_map = Map::CopyForObserved(old_map);
} else {
new_map = Map::Copy(old_map);
new_map->set_is_observed();
}
JSObject::MigrateToMap(object, new_map);
}
Handle<Object> JSObject::FastPropertyAt(Handle<JSObject> object,
Representation representation,
FieldIndex index) {
Isolate* isolate = object->GetIsolate();
Handle<Object> raw_value(object->RawFastPropertyAt(index), isolate);
return Object::WrapForRead(isolate, raw_value, representation);
}
template<class ContextObject>
class JSObjectWalkVisitor {
public:
JSObjectWalkVisitor(ContextObject* site_context, bool copying,
JSObject::DeepCopyHints hints)
: site_context_(site_context),
copying_(copying),
hints_(hints) {}
MUST_USE_RESULT MaybeHandle<JSObject> StructureWalk(Handle<JSObject> object);
protected:
MUST_USE_RESULT inline MaybeHandle<JSObject> VisitElementOrProperty(
Handle<JSObject> object,
Handle<JSObject> value) {
Handle<AllocationSite> current_site = site_context()->EnterNewScope();
MaybeHandle<JSObject> copy_of_value = StructureWalk(value);
site_context()->ExitScope(current_site, value);
return copy_of_value;
}
inline ContextObject* site_context() { return site_context_; }
inline Isolate* isolate() { return site_context()->isolate(); }
inline bool copying() const { return copying_; }
private:
ContextObject* site_context_;
const bool copying_;
const JSObject::DeepCopyHints hints_;
};
template <class ContextObject>
MaybeHandle<JSObject> JSObjectWalkVisitor<ContextObject>::StructureWalk(
Handle<JSObject> object) {
Isolate* isolate = this->isolate();
bool copying = this->copying();
bool shallow = hints_ == JSObject::kObjectIsShallow;
if (!shallow) {
StackLimitCheck check(isolate);
if (check.HasOverflowed()) {
isolate->StackOverflow();
return MaybeHandle<JSObject>();
}
}
if (object->map()->is_deprecated()) {
JSObject::MigrateInstance(object);
}
Handle<JSObject> copy;
if (copying) {
Handle<AllocationSite> site_to_pass;
if (site_context()->ShouldCreateMemento(object)) {
site_to_pass = site_context()->current();
}
copy = isolate->factory()->CopyJSObjectWithAllocationSite(
object, site_to_pass);
} else {
copy = object;
}
DCHECK(copying || copy.is_identical_to(object));
ElementsKind kind = copy->GetElementsKind();
if (copying && IsFastSmiOrObjectElementsKind(kind) &&
FixedArray::cast(copy->elements())->map() ==
isolate->heap()->fixed_cow_array_map()) {
isolate->counters()->cow_arrays_created_runtime()->Increment();
}
if (!shallow) {
HandleScope scope(isolate);
// Deep copy own properties.
if (copy->HasFastProperties()) {
Handle<DescriptorArray> descriptors(copy->map()->instance_descriptors());
int limit = copy->map()->NumberOfOwnDescriptors();
for (int i = 0; i < limit; i++) {
PropertyDetails details = descriptors->GetDetails(i);
if (details.type() != FIELD) continue;
FieldIndex index = FieldIndex::ForDescriptor(copy->map(), i);
Handle<Object> value(object->RawFastPropertyAt(index), isolate);
if (value->IsJSObject()) {
ASSIGN_RETURN_ON_EXCEPTION(
isolate, value,
VisitElementOrProperty(copy, Handle<JSObject>::cast(value)),
JSObject);
} else {
Representation representation = details.representation();
value = Object::NewStorageFor(isolate, value, representation);
}
if (copying) {
copy->FastPropertyAtPut(index, *value);
}
}
} else {
Handle<FixedArray> names =
isolate->factory()->NewFixedArray(copy->NumberOfOwnProperties());
copy->GetOwnPropertyNames(*names, 0);
for (int i = 0; i < names->length(); i++) {
DCHECK(names->get(i)->IsString());
Handle<String> key_string(String::cast(names->get(i)));
Maybe<PropertyAttributes> maybe =
JSReceiver::GetOwnPropertyAttributes(copy, key_string);
DCHECK(maybe.has_value);
PropertyAttributes attributes = maybe.value;
// Only deep copy fields from the object literal expression.
// In particular, don't try to copy the length attribute of
// an array.
if (attributes != NONE) continue;
Handle<Object> value =
Object::GetProperty(copy, key_string).ToHandleChecked();
if (value->IsJSObject()) {
Handle<JSObject> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
VisitElementOrProperty(copy, Handle<JSObject>::cast(value)),
JSObject);
if (copying) {
// Creating object copy for literals. No strict mode needed.
JSObject::SetProperty(copy, key_string, result, SLOPPY).Assert();
}
}
}
}
// Deep copy own elements.
// Pixel elements cannot be created using an object literal.
DCHECK(!copy->HasExternalArrayElements());
switch (kind) {
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS: {
Handle<FixedArray> elements(FixedArray::cast(copy->elements()));
if (elements->map() == isolate->heap()->fixed_cow_array_map()) {
#ifdef DEBUG
for (int i = 0; i < elements->length(); i++) {
DCHECK(!elements->get(i)->IsJSObject());
}
#endif
} else {
for (int i = 0; i < elements->length(); i++) {
Handle<Object> value(elements->get(i), isolate);
DCHECK(value->IsSmi() ||
value->IsTheHole() ||
(IsFastObjectElementsKind(copy->GetElementsKind())));
if (value->IsJSObject()) {
Handle<JSObject> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
VisitElementOrProperty(copy, Handle<JSObject>::cast(value)),
JSObject);
if (copying) {
elements->set(i, *result);
}
}
}
}
break;
}
case DICTIONARY_ELEMENTS: {
Handle<SeededNumberDictionary> element_dictionary(
copy->element_dictionary());
int capacity = element_dictionary->Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = element_dictionary->KeyAt(i);
if (element_dictionary->IsKey(k)) {
Handle<Object> value(element_dictionary->ValueAt(i), isolate);
if (value->IsJSObject()) {
Handle<JSObject> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
VisitElementOrProperty(copy, Handle<JSObject>::cast(value)),
JSObject);
if (copying) {
element_dictionary->ValueAtPut(i, *result);
}
}
}
}
break;
}
case SLOPPY_ARGUMENTS_ELEMENTS:
UNIMPLEMENTED();
break;
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS:
// No contained objects, nothing to do.
break;
}
}
return copy;
}
MaybeHandle<JSObject> JSObject::DeepWalk(
Handle<JSObject> object,
AllocationSiteCreationContext* site_context) {
JSObjectWalkVisitor<AllocationSiteCreationContext> v(site_context, false,
kNoHints);
MaybeHandle<JSObject> result = v.StructureWalk(object);
Handle<JSObject> for_assert;
DCHECK(!result.ToHandle(&for_assert) || for_assert.is_identical_to(object));
return result;
}
MaybeHandle<JSObject> JSObject::DeepCopy(
Handle<JSObject> object,
AllocationSiteUsageContext* site_context,
DeepCopyHints hints) {
JSObjectWalkVisitor<AllocationSiteUsageContext> v(site_context, true, hints);
MaybeHandle<JSObject> copy = v.StructureWalk(object);
Handle<JSObject> for_assert;
DCHECK(!copy.ToHandle(&for_assert) || !for_assert.is_identical_to(object));
return copy;
}
// Tests for the fast common case for property enumeration:
// - This object and all prototypes has an enum cache (which means that
// it is no proxy, has no interceptors and needs no access checks).
// - This object has no elements.
// - No prototype has enumerable properties/elements.
bool JSReceiver::IsSimpleEnum() {
for (PrototypeIterator iter(GetIsolate(), this,
PrototypeIterator::START_AT_RECEIVER);
!iter.IsAtEnd(); iter.Advance()) {
if (!iter.GetCurrent()->IsJSObject()) return false;
JSObject* curr = JSObject::cast(iter.GetCurrent());
int enum_length = curr->map()->EnumLength();
if (enum_length == kInvalidEnumCacheSentinel) return false;
if (curr->IsAccessCheckNeeded()) return false;
DCHECK(!curr->HasNamedInterceptor());
DCHECK(!curr->HasIndexedInterceptor());
if (curr->NumberOfEnumElements() > 0) return false;
if (curr != this && enum_length != 0) return false;
}
return true;
}
static bool FilterKey(Object* key, PropertyAttributes filter) {
if ((filter & SYMBOLIC) && key->IsSymbol()) {
return true;
}
if ((filter & PRIVATE_SYMBOL) &&
key->IsSymbol() && Symbol::cast(key)->is_private()) {
return true;
}
if ((filter & STRING) && !key->IsSymbol()) {
return true;
}
return false;
}
int Map::NumberOfDescribedProperties(DescriptorFlag which,
PropertyAttributes filter) {
int result = 0;
DescriptorArray* descs = instance_descriptors();
int limit = which == ALL_DESCRIPTORS
? descs->number_of_descriptors()
: NumberOfOwnDescriptors();
for (int i = 0; i < limit; i++) {
if ((descs->GetDetails(i).attributes() & filter) == 0 &&
!FilterKey(descs->GetKey(i), filter)) {
result++;
}
}
return result;
}
int Map::NextFreePropertyIndex() {
int max_index = -1;
int number_of_own_descriptors = NumberOfOwnDescriptors();
DescriptorArray* descs = instance_descriptors();
for (int i = 0; i < number_of_own_descriptors; i++) {
if (descs->GetType(i) == FIELD) {
int current_index = descs->GetFieldIndex(i);
if (current_index > max_index) max_index = current_index;
}
}
return max_index + 1;
}
static bool ContainsOnlyValidKeys(Handle<FixedArray> array) {
int len = array->length();
for (int i = 0; i < len; i++) {
Object* e = array->get(i);
if (!(e->IsString() || e->IsNumber())) return false;
}
return true;
}
static Handle<FixedArray> ReduceFixedArrayTo(
Handle<FixedArray> array, int length) {
DCHECK(array->length() >= length);
if (array->length() == length) return array;
Handle<FixedArray> new_array =
array->GetIsolate()->factory()->NewFixedArray(length);
for (int i = 0; i < length; ++i) new_array->set(i, array->get(i));
return new_array;
}
static Handle<FixedArray> GetEnumPropertyKeys(Handle<JSObject> object,
bool cache_result) {
Isolate* isolate = object->GetIsolate();
if (object->HasFastProperties()) {
int own_property_count = object->map()->EnumLength();
// If the enum length of the given map is set to kInvalidEnumCache, this
// means that the map itself has never used the present enum cache. The
// first step to using the cache is to set the enum length of the map by
// counting the number of own descriptors that are not DONT_ENUM or
// SYMBOLIC.
if (own_property_count == kInvalidEnumCacheSentinel) {
own_property_count = object->map()->NumberOfDescribedProperties(
OWN_DESCRIPTORS, DONT_SHOW);
} else {
DCHECK(own_property_count == object->map()->NumberOfDescribedProperties(
OWN_DESCRIPTORS, DONT_SHOW));
}
if (object->map()->instance_descriptors()->HasEnumCache()) {
DescriptorArray* desc = object->map()->instance_descriptors();
Handle<FixedArray> keys(desc->GetEnumCache(), isolate);
// In case the number of properties required in the enum are actually
// present, we can reuse the enum cache. Otherwise, this means that the
// enum cache was generated for a previous (smaller) version of the
// Descriptor Array. In that case we regenerate the enum cache.
if (own_property_count <= keys->length()) {
if (cache_result) object->map()->SetEnumLength(own_property_count);
isolate->counters()->enum_cache_hits()->Increment();
return ReduceFixedArrayTo(keys, own_property_count);
}
}
Handle<Map> map(object->map());
if (map->instance_descriptors()->IsEmpty()) {
isolate->counters()->enum_cache_hits()->Increment();
if (cache_result) map->SetEnumLength(0);
return isolate->factory()->empty_fixed_array();
}
isolate->counters()->enum_cache_misses()->Increment();
Handle<FixedArray> storage = isolate->factory()->NewFixedArray(
own_property_count);
Handle<FixedArray> indices = isolate->factory()->NewFixedArray(
own_property_count);
Handle<DescriptorArray> descs =
Handle<DescriptorArray>(object->map()->instance_descriptors(), isolate);
int size = map->NumberOfOwnDescriptors();
int index = 0;
for (int i = 0; i < size; i++) {
PropertyDetails details = descs->GetDetails(i);
Object* key = descs->GetKey(i);
if (!(details.IsDontEnum() || key->IsSymbol())) {
storage->set(index, key);
if (!indices.is_null()) {
if (details.type() != FIELD) {
indices = Handle<FixedArray>();
} else {
FieldIndex field_index = FieldIndex::ForDescriptor(*map, i);
int load_by_field_index = field_index.GetLoadByFieldIndex();
indices->set(index, Smi::FromInt(load_by_field_index));
}
}
index++;
}
}
DCHECK(index == storage->length());
Handle<FixedArray> bridge_storage =
isolate->factory()->NewFixedArray(
DescriptorArray::kEnumCacheBridgeLength);
DescriptorArray* desc = object->map()->instance_descriptors();
desc->SetEnumCache(*bridge_storage,
*storage,
indices.is_null() ? Object::cast(Smi::FromInt(0))
: Object::cast(*indices));
if (cache_result) {
object->map()->SetEnumLength(own_property_count);
}
return storage;
} else {
Handle<NameDictionary> dictionary(object->property_dictionary());
int length = dictionary->NumberOfEnumElements();
if (length == 0) {
return Handle<FixedArray>(isolate->heap()->empty_fixed_array());
}
Handle<FixedArray> storage = isolate->factory()->NewFixedArray(length);
dictionary->CopyEnumKeysTo(*storage);
return storage;
}
}
MaybeHandle<FixedArray> JSReceiver::GetKeys(Handle<JSReceiver> object,
KeyCollectionType type) {
USE(ContainsOnlyValidKeys);
Isolate* isolate = object->GetIsolate();
Handle<FixedArray> content = isolate->factory()->empty_fixed_array();
Handle<JSFunction> arguments_function(
JSFunction::cast(isolate->sloppy_arguments_map()->constructor()));
// Only collect keys if access is permitted.
for (PrototypeIterator iter(isolate, object,
PrototypeIterator::START_AT_RECEIVER);
!iter.IsAtEnd(); iter.Advance()) {
if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
Handle<JSProxy> proxy(JSProxy::cast(*PrototypeIterator::GetCurrent(iter)),
isolate);
Handle<Object> args[] = { proxy };
Handle<Object> names;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, names,
Execution::Call(isolate,
isolate->proxy_enumerate(),
object,
arraysize(args),
args),
FixedArray);
ASSIGN_RETURN_ON_EXCEPTION(
isolate, content,
FixedArray::AddKeysFromArrayLike(
content, Handle<JSObject>::cast(names)),
FixedArray);
break;
}
Handle<JSObject> current =
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter));
// Check access rights if required.
if (current->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(
current, isolate->factory()->undefined_value(), v8::ACCESS_KEYS)) {
isolate->ReportFailedAccessCheck(current, v8::ACCESS_KEYS);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, FixedArray);
break;
}
// Compute the element keys.
Handle<FixedArray> element_keys =
isolate->factory()->NewFixedArray(current->NumberOfEnumElements());
current->GetEnumElementKeys(*element_keys);
ASSIGN_RETURN_ON_EXCEPTION(
isolate, content,
FixedArray::UnionOfKeys(content, element_keys),
FixedArray);
DCHECK(ContainsOnlyValidKeys(content));
// Add the element keys from the interceptor.
if (current->HasIndexedInterceptor()) {
Handle<JSObject> result;
if (JSObject::GetKeysForIndexedInterceptor(
current, object).ToHandle(&result)) {
ASSIGN_RETURN_ON_EXCEPTION(
isolate, content,
FixedArray::AddKeysFromArrayLike(content, result),
FixedArray);
}
DCHECK(ContainsOnlyValidKeys(content));
}
// We can cache the computed property keys if access checks are
// not needed and no interceptors are involved.
//
// We do not use the cache if the object has elements and
// therefore it does not make sense to cache the property names
// for arguments objects. Arguments objects will always have
// elements.
// Wrapped strings have elements, but don't have an elements
// array or dictionary. So the fast inline test for whether to
// use the cache says yes, so we should not create a cache.
bool cache_enum_keys =
((current->map()->constructor() != *arguments_function) &&
!current->IsJSValue() &&
!current->IsAccessCheckNeeded() &&
!current->HasNamedInterceptor() &&
!current->HasIndexedInterceptor());
// Compute the property keys and cache them if possible.
ASSIGN_RETURN_ON_EXCEPTION(
isolate, content,
FixedArray::UnionOfKeys(
content, GetEnumPropertyKeys(current, cache_enum_keys)),
FixedArray);
DCHECK(ContainsOnlyValidKeys(content));
// Add the property keys from the interceptor.
if (current->HasNamedInterceptor()) {
Handle<JSObject> result;
if (JSObject::GetKeysForNamedInterceptor(
current, object).ToHandle(&result)) {
ASSIGN_RETURN_ON_EXCEPTION(
isolate, content,
FixedArray::AddKeysFromArrayLike(content, result),
FixedArray);
}
DCHECK(ContainsOnlyValidKeys(content));
}
// If we only want own properties we bail out after the first
// iteration.
if (type == OWN_ONLY) break;
}
return content;
}
// Try to update an accessor in an elements dictionary. Return true if the
// update succeeded, and false otherwise.
static bool UpdateGetterSetterInDictionary(
SeededNumberDictionary* dictionary,
uint32_t index,
Object* getter,
Object* setter,
PropertyAttributes attributes) {
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Object* result = dictionary->ValueAt(entry);
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS && result->IsAccessorPair()) {
DCHECK(details.IsConfigurable());
if (details.attributes() != attributes) {
dictionary->DetailsAtPut(
entry,
PropertyDetails(attributes, CALLBACKS, index));
}
AccessorPair::cast(result)->SetComponents(getter, setter);
return true;
}
}
return false;
}
void JSObject::DefineElementAccessor(Handle<JSObject> object,
uint32_t index,
Handle<Object> getter,
Handle<Object> setter,
PropertyAttributes attributes) {
switch (object->GetElementsKind()) {
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS:
break;
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
// Ignore getters and setters on pixel and external array elements.
return;
case DICTIONARY_ELEMENTS:
if (UpdateGetterSetterInDictionary(object->element_dictionary(),
index,
*getter,
*setter,
attributes)) {
return;
}
break;
case SLOPPY_ARGUMENTS_ELEMENTS: {
// Ascertain whether we have read-only properties or an existing
// getter/setter pair in an arguments elements dictionary backing
// store.
FixedArray* parameter_map = FixedArray::cast(object->elements());
uint32_t length = parameter_map->length();
Object* probe =
index < (length - 2) ? parameter_map->get(index + 2) : NULL;
if (probe == NULL || probe->IsTheHole()) {
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(arguments);
if (UpdateGetterSetterInDictionary(dictionary,
index,
*getter,
*setter,
attributes)) {
return;
}
}
}
break;
}
}
Isolate* isolate = object->GetIsolate();
Handle<AccessorPair> accessors = isolate->factory()->NewAccessorPair();
accessors->SetComponents(*getter, *setter);
SetElementCallback(object, index, accessors, attributes);
}
bool Map::DictionaryElementsInPrototypeChainOnly() {
if (IsDictionaryElementsKind(elements_kind())) {
return false;
}
for (PrototypeIterator iter(this); !iter.IsAtEnd(); iter.Advance()) {
if (iter.GetCurrent()->IsJSProxy()) {
// Be conservative, don't walk into proxies.
return true;
}
if (IsDictionaryElementsKind(
JSObject::cast(iter.GetCurrent())->map()->elements_kind())) {
return true;
}
}
return false;
}
void JSObject::SetElementCallback(Handle<JSObject> object,
uint32_t index,
Handle<Object> structure,
PropertyAttributes attributes) {
Heap* heap = object->GetHeap();
PropertyDetails details = PropertyDetails(attributes, CALLBACKS, 0);
// Normalize elements to make this operation simple.
bool had_dictionary_elements = object->HasDictionaryElements();
Handle<SeededNumberDictionary> dictionary = NormalizeElements(object);
DCHECK(object->HasDictionaryElements() ||
object->HasDictionaryArgumentsElements());
// Update the dictionary with the new CALLBACKS property.
dictionary = SeededNumberDictionary::Set(dictionary, index, structure,
details);
dictionary->set_requires_slow_elements();
// Update the dictionary backing store on the object.
if (object->elements()->map() == heap->sloppy_arguments_elements_map()) {
// Also delete any parameter alias.
//
// TODO(kmillikin): when deleting the last parameter alias we could
// switch to a direct backing store without the parameter map. This
// would allow GC of the context.
FixedArray* parameter_map = FixedArray::cast(object->elements());
if (index < static_cast<uint32_t>(parameter_map->length()) - 2) {
parameter_map->set(index + 2, heap->the_hole_value());
}
parameter_map->set(1, *dictionary);
} else {
object->set_elements(*dictionary);
if (!had_dictionary_elements) {
// KeyedStoreICs (at least the non-generic ones) need a reset.
heap->ClearAllICsByKind(Code::KEYED_STORE_IC);
}
}
}
void JSObject::SetPropertyCallback(Handle<JSObject> object,
Handle<Name> name,
Handle<Object> structure,
PropertyAttributes attributes) {
PropertyNormalizationMode mode = object->map()->is_prototype_map()
? KEEP_INOBJECT_PROPERTIES
: CLEAR_INOBJECT_PROPERTIES;
// Normalize object to make this operation simple.
NormalizeProperties(object, mode, 0);
// For the global object allocate a new map to invalidate the global inline
// caches which have a global property cell reference directly in the code.
if (object->IsGlobalObject()) {
Handle<Map> new_map = Map::CopyDropDescriptors(handle(object->map()));
DCHECK(new_map->is_dictionary_map());
JSObject::MigrateToMap(object, new_map);
// When running crankshaft, changing the map is not enough. We
// need to deoptimize all functions that rely on this global
// object.
Deoptimizer::DeoptimizeGlobalObject(*object);
}
// Update the dictionary with the new CALLBACKS property.
PropertyDetails details = PropertyDetails(attributes, CALLBACKS, 0);
SetNormalizedProperty(object, name, structure, details);
ReoptimizeIfPrototype(object);
}
MaybeHandle<Object> JSObject::DefineAccessor(Handle<JSObject> object,
Handle<Name> name,
Handle<Object> getter,
Handle<Object> setter,
PropertyAttributes attributes) {
Isolate* isolate = object->GetIsolate();
// Check access rights if needed.
if (object->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(object, name, v8::ACCESS_SET)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_SET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->undefined_value();
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return isolate->factory()->undefined_value();
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
DefineAccessor(Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)),
name, getter, setter, attributes);
return isolate->factory()->undefined_value();
}
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc(isolate);
// Try to flatten before operating on the string.
if (name->IsString()) name = String::Flatten(Handle<String>::cast(name));
uint32_t index = 0;
bool is_element = name->AsArrayIndex(&index);
Handle<Object> old_value = isolate->factory()->the_hole_value();
bool is_observed = object->map()->is_observed() &&
*name != isolate->heap()->hidden_string();
bool preexists = false;
if (is_observed) {
if (is_element) {
Maybe<bool> maybe = HasOwnElement(object, index);
// Workaround for a GCC 4.4.3 bug which leads to "‘preexists’ may be used
// uninitialized in this function".
if (!maybe.has_value) {
DCHECK(false);
return isolate->factory()->undefined_value();
}
preexists = maybe.value;
if (preexists && GetOwnElementAccessorPair(object, index).is_null()) {
old_value =
Object::GetElement(isolate, object, index).ToHandleChecked();
}
} else {
LookupIterator it(object, name, LookupIterator::HIDDEN_SKIP_INTERCEPTOR);
CHECK(GetPropertyAttributes(&it).has_value);
preexists = it.IsFound();
if (preexists && (it.state() == LookupIterator::DATA ||
it.GetAccessors()->IsAccessorInfo())) {
old_value = GetProperty(&it).ToHandleChecked();
}
}
}
if (is_element) {
DefineElementAccessor(object, index, getter, setter, attributes);
} else {
DCHECK(getter->IsSpecFunction() || getter->IsUndefined() ||
getter->IsNull());
DCHECK(setter->IsSpecFunction() || setter->IsUndefined() ||
setter->IsNull());
// At least one of the accessors needs to be a new value.
DCHECK(!getter->IsNull() || !setter->IsNull());
LookupIterator it(object, name, LookupIterator::OWN_SKIP_INTERCEPTOR);
if (it.state() == LookupIterator::ACCESS_CHECK) {
// We already did an access check before. We do have access.
it.Next();
}
if (!getter->IsNull()) {
it.TransitionToAccessorProperty(ACCESSOR_GETTER, getter, attributes);
}
if (!setter->IsNull()) {
it.TransitionToAccessorProperty(ACCESSOR_SETTER, setter, attributes);
}
}
if (is_observed) {
const char* type = preexists ? "reconfigure" : "add";
EnqueueChangeRecord(object, type, name, old_value);
}
return isolate->factory()->undefined_value();
}
MaybeHandle<Object> JSObject::SetAccessor(Handle<JSObject> object,
Handle<AccessorInfo> info) {
Isolate* isolate = object->GetIsolate();
Factory* factory = isolate->factory();
Handle<Name> name(Name::cast(info->name()));
// Check access rights if needed.
if (object->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(object, name, v8::ACCESS_SET)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_SET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return factory->undefined_value();
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return object;
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return SetAccessor(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), info);
}
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc(isolate);
// Try to flatten before operating on the string.
if (name->IsString()) name = String::Flatten(Handle<String>::cast(name));
uint32_t index = 0;
bool is_element = name->AsArrayIndex(&index);
if (is_element) {
if (object->IsJSArray()) return factory->undefined_value();
// Accessors overwrite previous callbacks (cf. with getters/setters).
switch (object->GetElementsKind()) {
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS:
break;
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
// Ignore getters and setters on pixel and external array
// elements.
return factory->undefined_value();
case DICTIONARY_ELEMENTS:
break;
case SLOPPY_ARGUMENTS_ELEMENTS:
UNIMPLEMENTED();
break;
}
SetElementCallback(object, index, info, info->property_attributes());
} else {
// Lookup the name.
LookupIterator it(object, name, LookupIterator::HIDDEN_SKIP_INTERCEPTOR);
CHECK(GetPropertyAttributes(&it).has_value);
// ES5 forbids turning a property into an accessor if it's not
// configurable. See 8.6.1 (Table 5).
if (it.IsFound() && (it.IsReadOnly() || !it.IsConfigurable())) {
return factory->undefined_value();
}
SetPropertyCallback(object, name, info, info->property_attributes());
}
return object;
}
MaybeHandle<Object> JSObject::GetAccessor(Handle<JSObject> object,
Handle<Name> name,
AccessorComponent component) {
Isolate* isolate = object->GetIsolate();
// Make sure that the top context does not change when doing callbacks or
// interceptor calls.
AssertNoContextChange ncc(isolate);
// Make the lookup and include prototypes.
uint32_t index = 0;
if (name->AsArrayIndex(&index)) {
for (PrototypeIterator iter(isolate, object,
PrototypeIterator::START_AT_RECEIVER);
!iter.IsAtEnd(); iter.Advance()) {
Handle<Object> current = PrototypeIterator::GetCurrent(iter);
// Check access rights if needed.
if (current->IsAccessCheckNeeded() &&
!isolate->MayNamedAccess(Handle<JSObject>::cast(current), name,
v8::ACCESS_HAS)) {
isolate->ReportFailedAccessCheck(Handle<JSObject>::cast(current),
v8::ACCESS_HAS);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->undefined_value();
}
if (current->IsJSObject() &&
Handle<JSObject>::cast(current)->HasDictionaryElements()) {
JSObject* js_object = JSObject::cast(*current);
SeededNumberDictionary* dictionary = js_object->element_dictionary();
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Object* element = dictionary->ValueAt(entry);
if (dictionary->DetailsAt(entry).type() == CALLBACKS &&
element->IsAccessorPair()) {
return handle(AccessorPair::cast(element)->GetComponent(component),
isolate);
}
}
}
}
} else {
LookupIterator it(object, name,
LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR);
for (; it.IsFound(); it.Next()) {
switch (it.state()) {
case LookupIterator::INTERCEPTOR:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::ACCESS_CHECK:
if (it.HasAccess(v8::ACCESS_HAS)) continue;
isolate->ReportFailedAccessCheck(it.GetHolder<JSObject>(),
v8::ACCESS_HAS);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return isolate->factory()->undefined_value();
case LookupIterator::JSPROXY:
return isolate->factory()->undefined_value();
case LookupIterator::DATA:
continue;
case LookupIterator::ACCESSOR: {
Handle<Object> maybe_pair = it.GetAccessors();
if (maybe_pair->IsAccessorPair()) {
return handle(
AccessorPair::cast(*maybe_pair)->GetComponent(component),
isolate);
}
}
}
}
}
return isolate->factory()->undefined_value();
}
Object* JSObject::SlowReverseLookup(Object* value) {
if (HasFastProperties()) {
int number_of_own_descriptors = map()->NumberOfOwnDescriptors();
DescriptorArray* descs = map()->instance_descriptors();
for (int i = 0; i < number_of_own_descriptors; i++) {
if (descs->GetType(i) == FIELD) {
Object* property =
RawFastPropertyAt(FieldIndex::ForDescriptor(map(), i));
if (descs->GetDetails(i).representation().IsDouble()) {
DCHECK(property->IsMutableHeapNumber());
if (value->IsNumber() && property->Number() == value->Number()) {
return descs->GetKey(i);
}
} else if (property == value) {
return descs->GetKey(i);
}
} else if (descs->GetType(i) == CONSTANT) {
if (descs->GetConstant(i) == value) {
return descs->GetKey(i);
}
}
}
return GetHeap()->undefined_value();
} else {
return property_dictionary()->SlowReverseLookup(value);
}
}
Handle<Map> Map::RawCopy(Handle<Map> map, int instance_size) {
Handle<Map> result = map->GetIsolate()->factory()->NewMap(
map->instance_type(), instance_size);
result->set_prototype(map->prototype());
result->set_constructor(map->constructor());
result->set_bit_field(map->bit_field());
result->set_bit_field2(map->bit_field2());
int new_bit_field3 = map->bit_field3();
new_bit_field3 = OwnsDescriptors::update(new_bit_field3, true);
new_bit_field3 = NumberOfOwnDescriptorsBits::update(new_bit_field3, 0);
new_bit_field3 = EnumLengthBits::update(new_bit_field3,
kInvalidEnumCacheSentinel);
new_bit_field3 = Deprecated::update(new_bit_field3, false);
if (!map->is_dictionary_map()) {
new_bit_field3 = IsUnstable::update(new_bit_field3, false);
}
new_bit_field3 = ConstructionCount::update(new_bit_field3,
JSFunction::kNoSlackTracking);
result->set_bit_field3(new_bit_field3);
return result;
}
Handle<Map> Map::Normalize(Handle<Map> fast_map,
PropertyNormalizationMode mode) {
DCHECK(!fast_map->is_dictionary_map());
Isolate* isolate = fast_map->GetIsolate();
Handle<Object> maybe_cache(isolate->native_context()->normalized_map_cache(),
isolate);
bool use_cache = !maybe_cache->IsUndefined();
Handle<NormalizedMapCache> cache;
if (use_cache) cache = Handle<NormalizedMapCache>::cast(maybe_cache);
Handle<Map> new_map;
if (use_cache && cache->Get(fast_map, mode).ToHandle(&new_map)) {
#ifdef VERIFY_HEAP
if (FLAG_verify_heap) new_map->DictionaryMapVerify();
#endif
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
// The cached map should match newly created normalized map bit-by-bit,
// except for the code cache, which can contain some ics which can be
// applied to the shared map.
Handle<Map> fresh = Map::CopyNormalized(fast_map, mode);
DCHECK(memcmp(fresh->address(),
new_map->address(),
Map::kCodeCacheOffset) == 0);
STATIC_ASSERT(Map::kDependentCodeOffset ==
Map::kCodeCacheOffset + kPointerSize);
int offset = Map::kDependentCodeOffset + kPointerSize;
DCHECK(memcmp(fresh->address() + offset,
new_map->address() + offset,
Map::kSize - offset) == 0);
}
#endif
} else {
new_map = Map::CopyNormalized(fast_map, mode);
if (use_cache) {
cache->Set(fast_map, new_map);
isolate->counters()->normalized_maps()->Increment();
}
}
fast_map->NotifyLeafMapLayoutChange();
return new_map;
}
Handle<Map> Map::CopyNormalized(Handle<Map> map,
PropertyNormalizationMode mode) {
int new_instance_size = map->instance_size();
if (mode == CLEAR_INOBJECT_PROPERTIES) {
new_instance_size -= map->inobject_properties() * kPointerSize;
}
Handle<Map> result = RawCopy(map, new_instance_size);
if (mode != CLEAR_INOBJECT_PROPERTIES) {
result->set_inobject_properties(map->inobject_properties());
}
result->set_dictionary_map(true);
result->set_migration_target(false);
#ifdef VERIFY_HEAP
if (FLAG_verify_heap) result->DictionaryMapVerify();
#endif
return result;
}
Handle<Map> Map::CopyDropDescriptors(Handle<Map> map) {
Handle<Map> result = RawCopy(map, map->instance_size());
// Please note instance_type and instance_size are set when allocated.
result->set_inobject_properties(map->inobject_properties());
result->set_unused_property_fields(map->unused_property_fields());
result->set_pre_allocated_property_fields(
map->pre_allocated_property_fields());
result->ClearCodeCache(map->GetHeap());
map->NotifyLeafMapLayoutChange();
return result;
}
Handle<Map> Map::ShareDescriptor(Handle<Map> map,
Handle<DescriptorArray> descriptors,
Descriptor* descriptor) {
// Sanity check. This path is only to be taken if the map owns its descriptor
// array, implying that its NumberOfOwnDescriptors equals the number of
// descriptors in the descriptor array.
DCHECK(map->NumberOfOwnDescriptors() ==
map->instance_descriptors()->number_of_descriptors());
Handle<Map> result = CopyDropDescriptors(map);
Handle<Name> name = descriptor->GetKey();
// Ensure there's space for the new descriptor in the shared descriptor array.
if (descriptors->NumberOfSlackDescriptors() == 0) {
int old_size = descriptors->number_of_descriptors();
if (old_size == 0) {
descriptors = DescriptorArray::Allocate(map->GetIsolate(), 0, 1);
} else {
EnsureDescriptorSlack(map, old_size < 4 ? 1 : old_size / 2);
descriptors = handle(map->instance_descriptors());
}
}
{
DisallowHeapAllocation no_gc;
descriptors->Append(descriptor);
result->InitializeDescriptors(*descriptors);
}
DCHECK(result->NumberOfOwnDescriptors() == map->NumberOfOwnDescriptors() + 1);
ConnectTransition(map, result, name, SIMPLE_TRANSITION);
return result;
}
void Map::ConnectTransition(Handle<Map> parent, Handle<Map> child,
Handle<Name> name, SimpleTransitionFlag flag) {
parent->set_owns_descriptors(false);
if (parent->is_prototype_map()) {
DCHECK(child->is_prototype_map());
} else {
Handle<TransitionArray> transitions =
TransitionArray::CopyInsert(parent, name, child, flag);
parent->set_transitions(*transitions);
child->SetBackPointer(*parent);
}
}
Handle<Map> Map::CopyReplaceDescriptors(Handle<Map> map,
Handle<DescriptorArray> descriptors,
TransitionFlag flag,
MaybeHandle<Name> maybe_name,
SimpleTransitionFlag simple_flag) {
DCHECK(descriptors->IsSortedNoDuplicates());
Handle<Map> result = CopyDropDescriptors(map);
result->InitializeDescriptors(*descriptors);
if (!map->is_prototype_map()) {
if (flag == INSERT_TRANSITION && map->CanHaveMoreTransitions()) {
Handle<Name> name;
CHECK(maybe_name.ToHandle(&name));
ConnectTransition(map, result, name, simple_flag);
} else {
int length = descriptors->number_of_descriptors();
for (int i = 0; i < length; i++) {
descriptors->SetRepresentation(i, Representation::Tagged());
if (descriptors->GetDetails(i).type() == FIELD) {
descriptors->SetValue(i, HeapType::Any());
}
}
}
}
return result;
}
// Since this method is used to rewrite an existing transition tree, it can
// always insert transitions without checking.
Handle<Map> Map::CopyInstallDescriptors(Handle<Map> map,
int new_descriptor,
Handle<DescriptorArray> descriptors) {
DCHECK(descriptors->IsSortedNoDuplicates());
Handle<Map> result = CopyDropDescriptors(map);
result->InitializeDescriptors(*descriptors);
result->SetNumberOfOwnDescriptors(new_descriptor + 1);
int unused_property_fields = map->unused_property_fields();
if (descriptors->GetDetails(new_descriptor).type() == FIELD) {
unused_property_fields = map->unused_property_fields() - 1;
if (unused_property_fields < 0) {
unused_property_fields += JSObject::kFieldsAdded;
}
}
result->set_unused_property_fields(unused_property_fields);
Handle<Name> name = handle(descriptors->GetKey(new_descriptor));
ConnectTransition(map, result, name, SIMPLE_TRANSITION);
return result;
}
Handle<Map> Map::CopyAsElementsKind(Handle<Map> map, ElementsKind kind,
TransitionFlag flag) {
if (flag == INSERT_TRANSITION) {
DCHECK(!map->HasElementsTransition() ||
((map->elements_transition_map()->elements_kind() ==
DICTIONARY_ELEMENTS ||
IsExternalArrayElementsKind(
map->elements_transition_map()->elements_kind())) &&
(kind == DICTIONARY_ELEMENTS ||
IsExternalArrayElementsKind(kind))));
DCHECK(!IsFastElementsKind(kind) ||
IsMoreGeneralElementsKindTransition(map->elements_kind(), kind));
DCHECK(kind != map->elements_kind());
}
bool insert_transition =
flag == INSERT_TRANSITION && !map->HasElementsTransition();
if (insert_transition && map->owns_descriptors()) {
// In case the map owned its own descriptors, share the descriptors and
// transfer ownership to the new map.
Handle<Map> new_map = CopyDropDescriptors(map);
ConnectElementsTransition(map, new_map);
new_map->set_elements_kind(kind);
new_map->InitializeDescriptors(map->instance_descriptors());
return new_map;
}
// In case the map did not own its own descriptors, a split is forced by
// copying the map; creating a new descriptor array cell.
// Create a new free-floating map only if we are not allowed to store it.
Handle<Map> new_map = Copy(map);
new_map->set_elements_kind(kind);
if (insert_transition) {
ConnectElementsTransition(map, new_map);
}
return new_map;
}
Handle<Map> Map::CopyForObserved(Handle<Map> map) {
DCHECK(!map->is_observed());
Isolate* isolate = map->GetIsolate();
// In case the map owned its own descriptors, share the descriptors and
// transfer ownership to the new map.
Handle<Map> new_map;
if (map->owns_descriptors()) {
new_map = CopyDropDescriptors(map);
} else {
DCHECK(!map->is_prototype_map());
new_map = Copy(map);
}
new_map->set_is_observed();
if (map->owns_descriptors()) {
new_map->InitializeDescriptors(map->instance_descriptors());
}
Handle<Name> name = isolate->factory()->observed_symbol();
ConnectTransition(map, new_map, name, FULL_TRANSITION);
return new_map;
}
Handle<Map> Map::Copy(Handle<Map> map) {
Handle<DescriptorArray> descriptors(map->instance_descriptors());
int number_of_own_descriptors = map->NumberOfOwnDescriptors();
Handle<DescriptorArray> new_descriptors =
DescriptorArray::CopyUpTo(descriptors, number_of_own_descriptors);
return CopyReplaceDescriptors(
map, new_descriptors, OMIT_TRANSITION, MaybeHandle<Name>());
}
Handle<Map> Map::Create(Isolate* isolate, int inobject_properties) {
Handle<Map> copy = Copy(handle(isolate->object_function()->initial_map()));
// Check that we do not overflow the instance size when adding the extra
// inobject properties. If the instance size overflows, we allocate as many
// properties as we can as inobject properties.
int max_extra_properties =
(JSObject::kMaxInstanceSize - JSObject::kHeaderSize) >> kPointerSizeLog2;
if (inobject_properties > max_extra_properties) {
inobject_properties = max_extra_properties;
}
int new_instance_size =
JSObject::kHeaderSize + kPointerSize * inobject_properties;
// Adjust the map with the extra inobject properties.
copy->set_inobject_properties(inobject_properties);
copy->set_unused_property_fields(inobject_properties);
copy->set_instance_size(new_instance_size);
copy->set_visitor_id(StaticVisitorBase::GetVisitorId(*copy));
return copy;
}
Handle<Map> Map::CopyForFreeze(Handle<Map> map) {
int num_descriptors = map->NumberOfOwnDescriptors();
Isolate* isolate = map->GetIsolate();
Handle<DescriptorArray> new_desc = DescriptorArray::CopyUpToAddAttributes(
handle(map->instance_descriptors(), isolate), num_descriptors, FROZEN);
Handle<Map> new_map = CopyReplaceDescriptors(
map, new_desc, INSERT_TRANSITION, isolate->factory()->frozen_symbol());
new_map->freeze();
new_map->set_is_extensible(false);
new_map->set_elements_kind(DICTIONARY_ELEMENTS);
return new_map;
}
bool DescriptorArray::CanHoldValue(int descriptor, Object* value) {
PropertyDetails details = GetDetails(descriptor);
switch (details.type()) {
case FIELD:
return value->FitsRepresentation(details.representation()) &&
GetFieldType(descriptor)->NowContains(value);
case CONSTANT:
DCHECK(GetConstant(descriptor) != value ||
value->FitsRepresentation(details.representation()));
return GetConstant(descriptor) == value;
case CALLBACKS:
return false;
case NORMAL:
UNREACHABLE();
break;
}
UNREACHABLE();
return false;
}
Handle<Map> Map::PrepareForDataProperty(Handle<Map> map, int descriptor,
Handle<Object> value) {
// Dictionaries can store any property value.
if (map->is_dictionary_map()) return map;
// Migrate to the newest map before storing the property.
map = Update(map);
Handle<DescriptorArray> descriptors(map->instance_descriptors());
if (descriptors->CanHoldValue(descriptor, *value)) return map;
Isolate* isolate = map->GetIsolate();
Representation representation = value->OptimalRepresentation();
Handle<HeapType> type = value->OptimalType(isolate, representation);
return GeneralizeRepresentation(map, descriptor, representation, type,
FORCE_FIELD);
}
Handle<Map> Map::TransitionToDataProperty(Handle<Map> map, Handle<Name> name,
Handle<Object> value,
PropertyAttributes attributes,
StoreFromKeyed store_mode) {
// Dictionary maps can always have additional data properties.
if (map->is_dictionary_map()) return map;
// Migrate to the newest map before storing the property.
map = Update(map);
int index = map->SearchTransition(*name);
if (index != TransitionArray::kNotFound) {
Handle<Map> transition(map->GetTransition(index));
int descriptor = transition->LastAdded();
// TODO(verwaest): Handle attributes better.
DescriptorArray* descriptors = transition->instance_descriptors();
if (descriptors->GetDetails(descriptor).attributes() != attributes) {
return Map::Normalize(map, CLEAR_INOBJECT_PROPERTIES);
}
return Map::PrepareForDataProperty(transition, descriptor, value);
}
TransitionFlag flag = INSERT_TRANSITION;
MaybeHandle<Map> maybe_map;
if (value->IsJSFunction()) {
maybe_map = Map::CopyWithConstant(map, name, value, attributes, flag);
} else if (!map->TooManyFastProperties(store_mode)) {
Isolate* isolate = name->GetIsolate();
Representation representation = value->OptimalRepresentation();
Handle<HeapType> type = value->OptimalType(isolate, representation);
maybe_map =
Map::CopyWithField(map, name, type, attributes, representation, flag);
}
Handle<Map> result;
if (!maybe_map.ToHandle(&result)) {
return Map::Normalize(map, CLEAR_INOBJECT_PROPERTIES);
}
return result;
}
Handle<Map> Map::ReconfigureDataProperty(Handle<Map> map, int descriptor,
PropertyAttributes attributes) {
// Dictionaries have to be reconfigured in-place.
DCHECK(!map->is_dictionary_map());
// For now, give up on transitioning and just create a unique map.
// TODO(verwaest/ishell): Cache transitions with different attributes.
return CopyGeneralizeAllRepresentations(map, descriptor, FORCE_FIELD,
attributes, "attributes mismatch");
}
Handle<Map> Map::TransitionToAccessorProperty(Handle<Map> map,
Handle<Name> name,
AccessorComponent component,
Handle<Object> accessor,
PropertyAttributes attributes) {
Isolate* isolate = name->GetIsolate();
// Dictionary maps can always have additional data properties.
if (map->is_dictionary_map()) {
// For global objects, property cells are inlined. We need to change the
// map.
if (map->IsGlobalObjectMap()) return Copy(map);
return map;
}
// Migrate to the newest map before transitioning to the new property.
map = Update(map);
PropertyNormalizationMode mode = map->is_prototype_map()
? KEEP_INOBJECT_PROPERTIES
: CLEAR_INOBJECT_PROPERTIES;
int index = map->SearchTransition(*name);
if (index != TransitionArray::kNotFound) {
Handle<Map> transition(map->GetTransition(index));
DescriptorArray* descriptors = transition->instance_descriptors();
// Fast path, assume that we're modifying the last added descriptor.
int descriptor = transition->LastAdded();
if (descriptors->GetKey(descriptor) != *name) {
// If not, search for the descriptor.
descriptor = descriptors->SearchWithCache(*name, *transition);
}
if (descriptors->GetDetails(descriptor).type() != CALLBACKS) {
return Map::Normalize(map, mode);
}
// TODO(verwaest): Handle attributes better.
if (descriptors->GetDetails(descriptor).attributes() != attributes) {
return Map::Normalize(map, mode);
}
Handle<Object> maybe_pair(descriptors->GetValue(descriptor), isolate);
if (!maybe_pair->IsAccessorPair()) {
return Map::Normalize(map, mode);
}
Handle<AccessorPair> pair = Handle<AccessorPair>::cast(maybe_pair);
if (pair->get(component) != *accessor) {
return Map::Normalize(map, mode);
}
return transition;
}
Handle<AccessorPair> pair;
DescriptorArray* old_descriptors = map->instance_descriptors();
int descriptor = old_descriptors->SearchWithCache(*name, *map);
if (descriptor != DescriptorArray::kNotFound) {
PropertyDetails old_details = old_descriptors->GetDetails(descriptor);
if (old_details.type() != CALLBACKS) {
return Map::Normalize(map, mode);
}
if (old_details.attributes() != attributes) {
return Map::Normalize(map, mode);
}
Handle<Object> maybe_pair(old_descriptors->GetValue(descriptor), isolate);
if (!maybe_pair->IsAccessorPair()) {
return Map::Normalize(map, mode);
}
Object* current = Handle<AccessorPair>::cast(maybe_pair)->get(component);
if (current == *accessor) return map;
if (!current->IsTheHole()) {
return Map::Normalize(map, mode);
}
pair = AccessorPair::Copy(Handle<AccessorPair>::cast(maybe_pair));
} else if (map->NumberOfOwnDescriptors() >= kMaxNumberOfDescriptors ||
map->TooManyFastProperties(CERTAINLY_NOT_STORE_FROM_KEYED)) {
return Map::Normalize(map, CLEAR_INOBJECT_PROPERTIES);
} else {
pair = isolate->factory()->NewAccessorPair();
}
pair->set(component, *accessor);
TransitionFlag flag = INSERT_TRANSITION;
CallbacksDescriptor new_desc(name, pair, attributes);
return Map::CopyInsertDescriptor(map, &new_desc, flag);
}
Handle<Map> Map::CopyAddDescriptor(Handle<Map> map,
Descriptor* descriptor,
TransitionFlag flag) {
Handle<DescriptorArray> descriptors(map->instance_descriptors());
// Ensure the key is unique.
descriptor->KeyToUniqueName();
if (flag == INSERT_TRANSITION &&
map->owns_descriptors() &&
map->CanHaveMoreTransitions()) {
return ShareDescriptor(map, descriptors, descriptor);
}
Handle<DescriptorArray> new_descriptors = DescriptorArray::CopyUpTo(
descriptors, map->NumberOfOwnDescriptors(), 1);
new_descriptors->Append(descriptor);
return CopyReplaceDescriptors(
map, new_descriptors, flag, descriptor->GetKey(), SIMPLE_TRANSITION);
}
Handle<Map> Map::CopyInsertDescriptor(Handle<Map> map,
Descriptor* descriptor,
TransitionFlag flag) {
Handle<DescriptorArray> old_descriptors(map->instance_descriptors());
// Ensure the key is unique.
descriptor->KeyToUniqueName();
// We replace the key if it is already present.
int index = old_descriptors->SearchWithCache(*descriptor->GetKey(), *map);
if (index != DescriptorArray::kNotFound) {
return CopyReplaceDescriptor(map, old_descriptors, descriptor, index, flag);
}
return CopyAddDescriptor(map, descriptor, flag);
}
Handle<DescriptorArray> DescriptorArray::CopyUpTo(
Handle<DescriptorArray> desc,
int enumeration_index,
int slack) {
return DescriptorArray::CopyUpToAddAttributes(
desc, enumeration_index, NONE, slack);
}
Handle<DescriptorArray> DescriptorArray::CopyUpToAddAttributes(
Handle<DescriptorArray> desc,
int enumeration_index,
PropertyAttributes attributes,
int slack) {
if (enumeration_index + slack == 0) {
return desc->GetIsolate()->factory()->empty_descriptor_array();
}
int size = enumeration_index;
Handle<DescriptorArray> descriptors =
DescriptorArray::Allocate(desc->GetIsolate(), size, slack);
DescriptorArray::WhitenessWitness witness(*descriptors);
if (attributes != NONE) {
for (int i = 0; i < size; ++i) {
Object* value = desc->GetValue(i);
Name* key = desc->GetKey(i);
PropertyDetails details = desc->GetDetails(i);
// Bulk attribute changes never affect private properties.
if (!key->IsSymbol() || !Symbol::cast(key)->is_private()) {
int mask = DONT_DELETE | DONT_ENUM;
// READ_ONLY is an invalid attribute for JS setters/getters.
if (details.type() != CALLBACKS || !value->IsAccessorPair()) {
mask |= READ_ONLY;
}
details = details.CopyAddAttributes(
static_cast<PropertyAttributes>(attributes & mask));
}
Descriptor inner_desc(
handle(key), handle(value, desc->GetIsolate()), details);
descriptors->Set(i, &inner_desc, witness);
}
} else {
for (int i = 0; i < size; ++i) {
descriptors->CopyFrom(i, *desc, witness);
}
}
if (desc->number_of_descriptors() != enumeration_index) descriptors->Sort();
return descriptors;
}
Handle<Map> Map::CopyReplaceDescriptor(Handle<Map> map,
Handle<DescriptorArray> descriptors,
Descriptor* descriptor,
int insertion_index,
TransitionFlag flag) {
// Ensure the key is unique.
descriptor->KeyToUniqueName();
Handle<Name> key = descriptor->GetKey();
DCHECK(*key == descriptors->GetKey(insertion_index));
Handle<DescriptorArray> new_descriptors = DescriptorArray::CopyUpTo(
descriptors, map->NumberOfOwnDescriptors());
new_descriptors->Replace(insertion_index, descriptor);
SimpleTransitionFlag simple_flag =
(insertion_index == descriptors->number_of_descriptors() - 1)
? SIMPLE_TRANSITION
: FULL_TRANSITION;
return CopyReplaceDescriptors(map, new_descriptors, flag, key, simple_flag);
}
void Map::UpdateCodeCache(Handle<Map> map,
Handle<Name> name,
Handle<Code> code) {
Isolate* isolate = map->GetIsolate();
HandleScope scope(isolate);
// Allocate the code cache if not present.
if (map->code_cache()->IsFixedArray()) {
Handle<Object> result = isolate->factory()->NewCodeCache();
map->set_code_cache(*result);
}
// Update the code cache.
Handle<CodeCache> code_cache(CodeCache::cast(map->code_cache()), isolate);
CodeCache::Update(code_cache, name, code);
}
Object* Map::FindInCodeCache(Name* name, Code::Flags flags) {
// Do a lookup if a code cache exists.
if (!code_cache()->IsFixedArray()) {
return CodeCache::cast(code_cache())->Lookup(name, flags);
} else {
return GetHeap()->undefined_value();
}
}
int Map::IndexInCodeCache(Object* name, Code* code) {
// Get the internal index if a code cache exists.
if (!code_cache()->IsFixedArray()) {
return CodeCache::cast(code_cache())->GetIndex(name, code);
}
return -1;
}
void Map::RemoveFromCodeCache(Name* name, Code* code, int index) {
// No GC is supposed to happen between a call to IndexInCodeCache and
// RemoveFromCodeCache so the code cache must be there.
DCHECK(!code_cache()->IsFixedArray());
CodeCache::cast(code_cache())->RemoveByIndex(name, code, index);
}
// An iterator over all map transitions in an descriptor array, reusing the
// constructor field of the map while it is running. Negative values in
// the constructor field indicate an active map transition iteration. The
// original constructor is restored after iterating over all entries.
class IntrusiveMapTransitionIterator {
public:
IntrusiveMapTransitionIterator(
Map* map, TransitionArray* transition_array, Object* constructor)
: map_(map),
transition_array_(transition_array),
constructor_(constructor) { }
void StartIfNotStarted() {
DCHECK(!(*IteratorField())->IsSmi() || IsIterating());
if (!(*IteratorField())->IsSmi()) {
DCHECK(*IteratorField() == constructor_);
*IteratorField() = Smi::FromInt(-1);
}
}
bool IsIterating() {
return (*IteratorField())->IsSmi() &&
Smi::cast(*IteratorField())->value() < 0;
}
Map* Next() {
DCHECK(IsIterating());
int value = Smi::cast(*IteratorField())->value();
int index = -value - 1;
int number_of_transitions = transition_array_->number_of_transitions();
while (index < number_of_transitions) {
*IteratorField() = Smi::FromInt(value - 1);
return transition_array_->GetTarget(index);
}
*IteratorField() = constructor_;
return NULL;
}
private:
Object** IteratorField() {
return HeapObject::RawField(map_, Map::kConstructorOffset);
}
Map* map_;
TransitionArray* transition_array_;
Object* constructor_;
};
// An iterator over all prototype transitions, reusing the constructor field
// of the map while it is running. Positive values in the constructor field
// indicate an active prototype transition iteration. The original constructor
// is restored after iterating over all entries.
class IntrusivePrototypeTransitionIterator {
public:
IntrusivePrototypeTransitionIterator(
Map* map, HeapObject* proto_trans, Object* constructor)
: map_(map), proto_trans_(proto_trans), constructor_(constructor) { }
void StartIfNotStarted() {
if (!(*IteratorField())->IsSmi()) {
DCHECK(*IteratorField() == constructor_);
*IteratorField() = Smi::FromInt(0);
}
}
bool IsIterating() {
return (*IteratorField())->IsSmi() &&
Smi::cast(*IteratorField())->value() >= 0;
}
Map* Next() {
DCHECK(IsIterating());
int transitionNumber = Smi::cast(*IteratorField())->value();
if (transitionNumber < NumberOfTransitions()) {
*IteratorField() = Smi::FromInt(transitionNumber + 1);
return GetTransition(transitionNumber);
}
*IteratorField() = constructor_;
return NULL;
}
private:
Object** IteratorField() {
return HeapObject::RawField(map_, Map::kConstructorOffset);
}
int NumberOfTransitions() {
FixedArray* proto_trans = reinterpret_cast<FixedArray*>(proto_trans_);
Object* num = proto_trans->get(Map::kProtoTransitionNumberOfEntriesOffset);
return Smi::cast(num)->value();
}
Map* GetTransition(int transitionNumber) {
FixedArray* proto_trans = reinterpret_cast<FixedArray*>(proto_trans_);
return Map::cast(proto_trans->get(IndexFor(transitionNumber)));
}
int IndexFor(int transitionNumber) {
return Map::kProtoTransitionHeaderSize +
Map::kProtoTransitionMapOffset +
transitionNumber * Map::kProtoTransitionElementsPerEntry;
}
Map* map_;
HeapObject* proto_trans_;
Object* constructor_;
};
// To traverse the transition tree iteratively, we have to store two kinds of
// information in a map: The parent map in the traversal and which children of a
// node have already been visited. To do this without additional memory, we
// temporarily reuse two fields with known values:
//
// (1) The map of the map temporarily holds the parent, and is restored to the
// meta map afterwards.
//
// (2) The info which children have already been visited depends on which part
// of the map we currently iterate. We use the constructor field of the
// map to store the current index. We can do that because the constructor
// is the same for all involved maps.
//
// (a) If we currently follow normal map transitions, we temporarily store
// the current index in the constructor field, and restore it to the
// original constructor afterwards. Note that a single descriptor can
// have 0, 1, or 2 transitions.
//
// (b) If we currently follow prototype transitions, we temporarily store
// the current index in the constructor field, and restore it to the
// original constructor afterwards.
//
// Note that the child iterator is just a concatenation of two iterators: One
// iterating over map transitions and one iterating over prototype transisitons.
class TraversableMap : public Map {
public:
// Record the parent in the traversal within this map. Note that this destroys
// this map's map!
void SetParent(TraversableMap* parent) { set_map_no_write_barrier(parent); }
// Reset the current map's map, returning the parent previously stored in it.
TraversableMap* GetAndResetParent() {
TraversableMap* old_parent = static_cast<TraversableMap*>(map());
set_map_no_write_barrier(GetHeap()->meta_map());
return old_parent;
}
// If we have an unvisited child map, return that one and advance. If we have
// none, return NULL and restore the overwritten constructor field.
TraversableMap* ChildIteratorNext(Object* constructor) {
if (!HasTransitionArray()) return NULL;
TransitionArray* transition_array = transitions();
if (transition_array->HasPrototypeTransitions()) {
HeapObject* proto_transitions =
transition_array->GetPrototypeTransitions();
IntrusivePrototypeTransitionIterator proto_iterator(this,
proto_transitions,
constructor);
proto_iterator.StartIfNotStarted();
if (proto_iterator.IsIterating()) {
Map* next = proto_iterator.Next();
if (next != NULL) return static_cast<TraversableMap*>(next);
}
}
IntrusiveMapTransitionIterator transition_iterator(this,
transition_array,
constructor);
transition_iterator.StartIfNotStarted();
if (transition_iterator.IsIterating()) {
Map* next = transition_iterator.Next();
if (next != NULL) return static_cast<TraversableMap*>(next);
}
return NULL;
}
};
// Traverse the transition tree in postorder without using the C++ stack by
// doing pointer reversal.
void Map::TraverseTransitionTree(TraverseCallback callback, void* data) {
// Make sure that we do not allocate in the callback.
DisallowHeapAllocation no_allocation;
TraversableMap* current = static_cast<TraversableMap*>(this);
// Get the root constructor here to restore it later when finished iterating
// over maps.
Object* root_constructor = constructor();
while (true) {
TraversableMap* child = current->ChildIteratorNext(root_constructor);
if (child != NULL) {
child->SetParent(current);
current = child;
} else {
TraversableMap* parent = current->GetAndResetParent();
callback(current, data);
if (current == this) break;
current = parent;
}
}
}
void CodeCache::Update(
Handle<CodeCache> code_cache, Handle<Name> name, Handle<Code> code) {
// The number of monomorphic stubs for normal load/store/call IC's can grow to
// a large number and therefore they need to go into a hash table. They are
// used to load global properties from cells.
if (code->type() == Code::NORMAL) {
// Make sure that a hash table is allocated for the normal load code cache.
if (code_cache->normal_type_cache()->IsUndefined()) {
Handle<Object> result =
CodeCacheHashTable::New(code_cache->GetIsolate(),
CodeCacheHashTable::kInitialSize);
code_cache->set_normal_type_cache(*result);
}
UpdateNormalTypeCache(code_cache, name, code);
} else {
DCHECK(code_cache->default_cache()->IsFixedArray());
UpdateDefaultCache(code_cache, name, code);
}
}
void CodeCache::UpdateDefaultCache(
Handle<CodeCache> code_cache, Handle<Name> name, Handle<Code> code) {
// When updating the default code cache we disregard the type encoded in the
// flags. This allows call constant stubs to overwrite call field
// stubs, etc.
Code::Flags flags = Code::RemoveTypeFromFlags(code->flags());
// First check whether we can update existing code cache without
// extending it.
Handle<FixedArray> cache = handle(code_cache->default_cache());
int length = cache->length();
{
DisallowHeapAllocation no_alloc;
int deleted_index = -1;
for (int i = 0; i < length; i += kCodeCacheEntrySize) {
Object* key = cache->get(i);
if (key->IsNull()) {
if (deleted_index < 0) deleted_index = i;
continue;
}
if (key->IsUndefined()) {
if (deleted_index >= 0) i = deleted_index;
cache->set(i + kCodeCacheEntryNameOffset, *name);
cache->set(i + kCodeCacheEntryCodeOffset, *code);
return;
}
if (name->Equals(Name::cast(key))) {
Code::Flags found =
Code::cast(cache->get(i + kCodeCacheEntryCodeOffset))->flags();
if (Code::RemoveTypeFromFlags(found) == flags) {
cache->set(i + kCodeCacheEntryCodeOffset, *code);
return;
}
}
}
// Reached the end of the code cache. If there were deleted
// elements, reuse the space for the first of them.
if (deleted_index >= 0) {
cache->set(deleted_index + kCodeCacheEntryNameOffset, *name);
cache->set(deleted_index + kCodeCacheEntryCodeOffset, *code);
return;
}
}
// Extend the code cache with some new entries (at least one). Must be a
// multiple of the entry size.
int new_length = length + ((length >> 1)) + kCodeCacheEntrySize;
new_length = new_length - new_length % kCodeCacheEntrySize;
DCHECK((new_length % kCodeCacheEntrySize) == 0);
cache = FixedArray::CopySize(cache, new_length);
// Add the (name, code) pair to the new cache.
cache->set(length + kCodeCacheEntryNameOffset, *name);
cache->set(length + kCodeCacheEntryCodeOffset, *code);
code_cache->set_default_cache(*cache);
}
void CodeCache::UpdateNormalTypeCache(
Handle<CodeCache> code_cache, Handle<Name> name, Handle<Code> code) {
// Adding a new entry can cause a new cache to be allocated.
Handle<CodeCacheHashTable> cache(
CodeCacheHashTable::cast(code_cache->normal_type_cache()));
Handle<Object> new_cache = CodeCacheHashTable::Put(cache, name, code);
code_cache->set_normal_type_cache(*new_cache);
}
Object* CodeCache::Lookup(Name* name, Code::Flags flags) {
Object* result = LookupDefaultCache(name, Code::RemoveTypeFromFlags(flags));
if (result->IsCode()) {
if (Code::cast(result)->flags() == flags) return result;
return GetHeap()->undefined_value();
}
return LookupNormalTypeCache(name, flags);
}
Object* CodeCache::LookupDefaultCache(Name* name, Code::Flags flags) {
FixedArray* cache = default_cache();
int length = cache->length();
for (int i = 0; i < length; i += kCodeCacheEntrySize) {
Object* key = cache->get(i + kCodeCacheEntryNameOffset);
// Skip deleted elements.
if (key->IsNull()) continue;
if (key->IsUndefined()) return key;
if (name->Equals(Name::cast(key))) {
Code* code = Code::cast(cache->get(i + kCodeCacheEntryCodeOffset));
if (Code::RemoveTypeFromFlags(code->flags()) == flags) {
return code;
}
}
}
return GetHeap()->undefined_value();
}
Object* CodeCache::LookupNormalTypeCache(Name* name, Code::Flags flags) {
if (!normal_type_cache()->IsUndefined()) {
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
return cache->Lookup(name, flags);
} else {
return GetHeap()->undefined_value();
}
}
int CodeCache::GetIndex(Object* name, Code* code) {
if (code->type() == Code::NORMAL) {
if (normal_type_cache()->IsUndefined()) return -1;
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
return cache->GetIndex(Name::cast(name), code->flags());
}
FixedArray* array = default_cache();
int len = array->length();
for (int i = 0; i < len; i += kCodeCacheEntrySize) {
if (array->get(i + kCodeCacheEntryCodeOffset) == code) return i + 1;
}
return -1;
}
void CodeCache::RemoveByIndex(Object* name, Code* code, int index) {
if (code->type() == Code::NORMAL) {
DCHECK(!normal_type_cache()->IsUndefined());
CodeCacheHashTable* cache = CodeCacheHashTable::cast(normal_type_cache());
DCHECK(cache->GetIndex(Name::cast(name), code->flags()) == index);
cache->RemoveByIndex(index);
} else {
FixedArray* array = default_cache();
DCHECK(array->length() >= index && array->get(index)->IsCode());
// Use null instead of undefined for deleted elements to distinguish
// deleted elements from unused elements. This distinction is used
// when looking up in the cache and when updating the cache.
DCHECK_EQ(1, kCodeCacheEntryCodeOffset - kCodeCacheEntryNameOffset);
array->set_null(index - 1); // Name.
array->set_null(index); // Code.
}
}
// The key in the code cache hash table consists of the property name and the
// code object. The actual match is on the name and the code flags. If a key
// is created using the flags and not a code object it can only be used for
// lookup not to create a new entry.
class CodeCacheHashTableKey : public HashTableKey {
public:
CodeCacheHashTableKey(Handle<Name> name, Code::Flags flags)
: name_(name), flags_(flags), code_() { }
CodeCacheHashTableKey(Handle<Name> name, Handle<Code> code)
: name_(name), flags_(code->flags()), code_(code) { }
bool IsMatch(Object* other) OVERRIDE {
if (!other->IsFixedArray()) return false;
FixedArray* pair = FixedArray::cast(other);
Name* name = Name::cast(pair->get(0));
Code::Flags flags = Code::cast(pair->get(1))->flags();
if (flags != flags_) {
return false;
}
return name_->Equals(name);
}
static uint32_t NameFlagsHashHelper(Name* name, Code::Flags flags) {
return name->Hash() ^ flags;
}
uint32_t Hash() OVERRIDE { return NameFlagsHashHelper(*name_, flags_); }
uint32_t HashForObject(Object* obj) OVERRIDE {
FixedArray* pair = FixedArray::cast(obj);
Name* name = Name::cast(pair->get(0));
Code* code = Code::cast(pair->get(1));
return NameFlagsHashHelper(name, code->flags());
}
MUST_USE_RESULT Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
Handle<Code> code = code_.ToHandleChecked();
Handle<FixedArray> pair = isolate->factory()->NewFixedArray(2);
pair->set(0, *name_);
pair->set(1, *code);
return pair;
}
private:
Handle<Name> name_;
Code::Flags flags_;
// TODO(jkummerow): We should be able to get by without this.
MaybeHandle<Code> code_;
};
Object* CodeCacheHashTable::Lookup(Name* name, Code::Flags flags) {
DisallowHeapAllocation no_alloc;
CodeCacheHashTableKey key(handle(name), flags);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
Handle<CodeCacheHashTable> CodeCacheHashTable::Put(
Handle<CodeCacheHashTable> cache, Handle<Name> name, Handle<Code> code) {
CodeCacheHashTableKey key(name, code);
Handle<CodeCacheHashTable> new_cache = EnsureCapacity(cache, 1, &key);
int entry = new_cache->FindInsertionEntry(key.Hash());
Handle<Object> k = key.AsHandle(cache->GetIsolate());
new_cache->set(EntryToIndex(entry), *k);
new_cache->set(EntryToIndex(entry) + 1, *code);
new_cache->ElementAdded();
return new_cache;
}
int CodeCacheHashTable::GetIndex(Name* name, Code::Flags flags) {
DisallowHeapAllocation no_alloc;
CodeCacheHashTableKey key(handle(name), flags);
int entry = FindEntry(&key);
return (entry == kNotFound) ? -1 : entry;
}
void CodeCacheHashTable::RemoveByIndex(int index) {
DCHECK(index >= 0);
Heap* heap = GetHeap();
set(EntryToIndex(index), heap->the_hole_value());
set(EntryToIndex(index) + 1, heap->the_hole_value());
ElementRemoved();
}
void PolymorphicCodeCache::Update(Handle<PolymorphicCodeCache> code_cache,
MapHandleList* maps,
Code::Flags flags,
Handle<Code> code) {
Isolate* isolate = code_cache->GetIsolate();
if (code_cache->cache()->IsUndefined()) {
Handle<PolymorphicCodeCacheHashTable> result =
PolymorphicCodeCacheHashTable::New(
isolate,
PolymorphicCodeCacheHashTable::kInitialSize);
code_cache->set_cache(*result);
} else {
// This entry shouldn't be contained in the cache yet.
DCHECK(PolymorphicCodeCacheHashTable::cast(code_cache->cache())
->Lookup(maps, flags)->IsUndefined());
}
Handle<PolymorphicCodeCacheHashTable> hash_table =
handle(PolymorphicCodeCacheHashTable::cast(code_cache->cache()));
Handle<PolymorphicCodeCacheHashTable> new_cache =
PolymorphicCodeCacheHashTable::Put(hash_table, maps, flags, code);
code_cache->set_cache(*new_cache);
}
Handle<Object> PolymorphicCodeCache::Lookup(MapHandleList* maps,
Code::Flags flags) {
if (!cache()->IsUndefined()) {
PolymorphicCodeCacheHashTable* hash_table =
PolymorphicCodeCacheHashTable::cast(cache());
return Handle<Object>(hash_table->Lookup(maps, flags), GetIsolate());
} else {
return GetIsolate()->factory()->undefined_value();
}
}
// Despite their name, object of this class are not stored in the actual
// hash table; instead they're temporarily used for lookups. It is therefore
// safe to have a weak (non-owning) pointer to a MapList as a member field.
class PolymorphicCodeCacheHashTableKey : public HashTableKey {
public:
// Callers must ensure that |maps| outlives the newly constructed object.
PolymorphicCodeCacheHashTableKey(MapHandleList* maps, int code_flags)
: maps_(maps),
code_flags_(code_flags) {}
bool IsMatch(Object* other) OVERRIDE {
MapHandleList other_maps(kDefaultListAllocationSize);
int other_flags;
FromObject(other, &other_flags, &other_maps);
if (code_flags_ != other_flags) return false;
if (maps_->length() != other_maps.length()) return false;
// Compare just the hashes first because it's faster.
int this_hash = MapsHashHelper(maps_, code_flags_);
int other_hash = MapsHashHelper(&other_maps, other_flags);
if (this_hash != other_hash) return false;
// Full comparison: for each map in maps_, look for an equivalent map in
// other_maps. This implementation is slow, but probably good enough for
// now because the lists are short (<= 4 elements currently).
for (int i = 0; i < maps_->length(); ++i) {
bool match_found = false;
for (int j = 0; j < other_maps.length(); ++j) {
if (*(maps_->at(i)) == *(other_maps.at(j))) {
match_found = true;
break;
}
}
if (!match_found) return false;
}
return true;
}
static uint32_t MapsHashHelper(MapHandleList* maps, int code_flags) {
uint32_t hash = code_flags;
for (int i = 0; i < maps->length(); ++i) {
hash ^= maps->at(i)->Hash();
}
return hash;
}
uint32_t Hash() OVERRIDE {
return MapsHashHelper(maps_, code_flags_);
}
uint32_t HashForObject(Object* obj) OVERRIDE {
MapHandleList other_maps(kDefaultListAllocationSize);
int other_flags;
FromObject(obj, &other_flags, &other_maps);
return MapsHashHelper(&other_maps, other_flags);
}
MUST_USE_RESULT Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
// The maps in |maps_| must be copied to a newly allocated FixedArray,
// both because the referenced MapList is short-lived, and because C++
// objects can't be stored in the heap anyway.
Handle<FixedArray> list =
isolate->factory()->NewUninitializedFixedArray(maps_->length() + 1);
list->set(0, Smi::FromInt(code_flags_));
for (int i = 0; i < maps_->length(); ++i) {
list->set(i + 1, *maps_->at(i));
}
return list;
}
private:
static MapHandleList* FromObject(Object* obj,
int* code_flags,
MapHandleList* maps) {
FixedArray* list = FixedArray::cast(obj);
maps->Rewind(0);
*code_flags = Smi::cast(list->get(0))->value();
for (int i = 1; i < list->length(); ++i) {
maps->Add(Handle<Map>(Map::cast(list->get(i))));
}
return maps;
}
MapHandleList* maps_; // weak.
int code_flags_;
static const int kDefaultListAllocationSize = kMaxKeyedPolymorphism + 1;
};
Object* PolymorphicCodeCacheHashTable::Lookup(MapHandleList* maps,
int code_kind) {
DisallowHeapAllocation no_alloc;
PolymorphicCodeCacheHashTableKey key(maps, code_kind);
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
Handle<PolymorphicCodeCacheHashTable> PolymorphicCodeCacheHashTable::Put(
Handle<PolymorphicCodeCacheHashTable> hash_table,
MapHandleList* maps,
int code_kind,
Handle<Code> code) {
PolymorphicCodeCacheHashTableKey key(maps, code_kind);
Handle<PolymorphicCodeCacheHashTable> cache =
EnsureCapacity(hash_table, 1, &key);
int entry = cache->FindInsertionEntry(key.Hash());
Handle<Object> obj = key.AsHandle(hash_table->GetIsolate());
cache->set(EntryToIndex(entry), *obj);
cache->set(EntryToIndex(entry) + 1, *code);
cache->ElementAdded();
return cache;
}
void FixedArray::Shrink(int new_length) {
DCHECK(0 <= new_length && new_length <= length());
if (new_length < length()) {
GetHeap()->RightTrimFixedArray<Heap::FROM_MUTATOR>(
this, length() - new_length);
}
}
MaybeHandle<FixedArray> FixedArray::AddKeysFromArrayLike(
Handle<FixedArray> content,
Handle<JSObject> array) {
DCHECK(array->IsJSArray() || array->HasSloppyArgumentsElements());
ElementsAccessor* accessor = array->GetElementsAccessor();
Handle<FixedArray> result;
ASSIGN_RETURN_ON_EXCEPTION(
array->GetIsolate(), result,
accessor->AddElementsToFixedArray(array, array, content),
FixedArray);
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
DisallowHeapAllocation no_allocation;
for (int i = 0; i < result->length(); i++) {
Object* current = result->get(i);
DCHECK(current->IsNumber() || current->IsName());
}
}
#endif
return result;
}
MaybeHandle<FixedArray> FixedArray::UnionOfKeys(Handle<FixedArray> first,
Handle<FixedArray> second) {
ElementsAccessor* accessor = ElementsAccessor::ForArray(second);
Handle<FixedArray> result;
ASSIGN_RETURN_ON_EXCEPTION(
first->GetIsolate(), result,
accessor->AddElementsToFixedArray(
Handle<Object>::null(), // receiver
Handle<JSObject>::null(), // holder
first,
Handle<FixedArrayBase>::cast(second)),
FixedArray);
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
DisallowHeapAllocation no_allocation;
for (int i = 0; i < result->length(); i++) {
Object* current = result->get(i);
DCHECK(current->IsNumber() || current->IsName());
}
}
#endif
return result;
}
Handle<FixedArray> FixedArray::CopySize(
Handle<FixedArray> array, int new_length, PretenureFlag pretenure) {
Isolate* isolate = array->GetIsolate();
if (new_length == 0) return isolate->factory()->empty_fixed_array();
Handle<FixedArray> result =
isolate->factory()->NewFixedArray(new_length, pretenure);
// Copy the content
DisallowHeapAllocation no_gc;
int len = array->length();
if (new_length < len) len = new_length;
// We are taking the map from the old fixed array so the map is sure to
// be an immortal immutable object.
result->set_map_no_write_barrier(array->map());
WriteBarrierMode mode = result->GetWriteBarrierMode(no_gc);
for (int i = 0; i < len; i++) {
result->set(i, array->get(i), mode);
}
return result;
}
void FixedArray::CopyTo(int pos, FixedArray* dest, int dest_pos, int len) {
DisallowHeapAllocation no_gc;
WriteBarrierMode mode = dest->GetWriteBarrierMode(no_gc);
for (int index = 0; index < len; index++) {
dest->set(dest_pos+index, get(pos+index), mode);
}
}
#ifdef DEBUG
bool FixedArray::IsEqualTo(FixedArray* other) {
if (length() != other->length()) return false;
for (int i = 0 ; i < length(); ++i) {
if (get(i) != other->get(i)) return false;
}
return true;
}
#endif
Handle<DescriptorArray> DescriptorArray::Allocate(Isolate* isolate,
int number_of_descriptors,
int slack) {
DCHECK(0 <= number_of_descriptors);
Factory* factory = isolate->factory();
// Do not use DescriptorArray::cast on incomplete object.
int size = number_of_descriptors + slack;
if (size == 0) return factory->empty_descriptor_array();
// Allocate the array of keys.
Handle<FixedArray> result = factory->NewFixedArray(LengthFor(size));
result->set(kDescriptorLengthIndex, Smi::FromInt(number_of_descriptors));
result->set(kEnumCacheIndex, Smi::FromInt(0));
return Handle<DescriptorArray>::cast(result);
}
void DescriptorArray::ClearEnumCache() {
set(kEnumCacheIndex, Smi::FromInt(0));
}
void DescriptorArray::Replace(int index, Descriptor* descriptor) {
descriptor->SetSortedKeyIndex(GetSortedKeyIndex(index));
Set(index, descriptor);
}
void DescriptorArray::SetEnumCache(FixedArray* bridge_storage,
FixedArray* new_cache,
Object* new_index_cache) {
DCHECK(bridge_storage->length() >= kEnumCacheBridgeLength);
DCHECK(new_index_cache->IsSmi() || new_index_cache->IsFixedArray());
DCHECK(!IsEmpty());
DCHECK(!HasEnumCache() || new_cache->length() > GetEnumCache()->length());
FixedArray::cast(bridge_storage)->
set(kEnumCacheBridgeCacheIndex, new_cache);
FixedArray::cast(bridge_storage)->
set(kEnumCacheBridgeIndicesCacheIndex, new_index_cache);
set(kEnumCacheIndex, bridge_storage);
}
void DescriptorArray::CopyFrom(int index,
DescriptorArray* src,
const WhitenessWitness& witness) {
Object* value = src->GetValue(index);
PropertyDetails details = src->GetDetails(index);
Descriptor desc(handle(src->GetKey(index)),
handle(value, src->GetIsolate()),
details);
Set(index, &desc, witness);
}
// We need the whiteness witness since sort will reshuffle the entries in the
// descriptor array. If the descriptor array were to be black, the shuffling
// would move a slot that was already recorded as pointing into an evacuation
// candidate. This would result in missing updates upon evacuation.
void DescriptorArray::Sort() {
// In-place heap sort.
int len = number_of_descriptors();
// Reset sorting since the descriptor array might contain invalid pointers.
for (int i = 0; i < len; ++i) SetSortedKey(i, i);
// Bottom-up max-heap construction.
// Index of the last node with children
const int max_parent_index = (len / 2) - 1;
for (int i = max_parent_index; i >= 0; --i) {
int parent_index = i;
const uint32_t parent_hash = GetSortedKey(i)->Hash();
while (parent_index <= max_parent_index) {
int child_index = 2 * parent_index + 1;
uint32_t child_hash = GetSortedKey(child_index)->Hash();
if (child_index + 1 < len) {
uint32_t right_child_hash = GetSortedKey(child_index + 1)->Hash();
if (right_child_hash > child_hash) {
child_index++;
child_hash = right_child_hash;
}
}
if (child_hash <= parent_hash) break;
SwapSortedKeys(parent_index, child_index);
// Now element at child_index could be < its children.
parent_index = child_index; // parent_hash remains correct.
}
}
// Extract elements and create sorted array.
for (int i = len - 1; i > 0; --i) {
// Put max element at the back of the array.
SwapSortedKeys(0, i);
// Shift down the new top element.
int parent_index = 0;
const uint32_t parent_hash = GetSortedKey(parent_index)->Hash();
const int max_parent_index = (i / 2) - 1;
while (parent_index <= max_parent_index) {
int child_index = parent_index * 2 + 1;
uint32_t child_hash = GetSortedKey(child_index)->Hash();
if (child_index + 1 < i) {
uint32_t right_child_hash = GetSortedKey(child_index + 1)->Hash();
if (right_child_hash > child_hash) {
child_index++;
child_hash = right_child_hash;
}
}
if (child_hash <= parent_hash) break;
SwapSortedKeys(parent_index, child_index);
parent_index = child_index;
}
}
DCHECK(IsSortedNoDuplicates());
}
Handle<AccessorPair> AccessorPair::Copy(Handle<AccessorPair> pair) {
Handle<AccessorPair> copy = pair->GetIsolate()->factory()->NewAccessorPair();
copy->set_getter(pair->getter());
copy->set_setter(pair->setter());
return copy;
}
Object* AccessorPair::GetComponent(AccessorComponent component) {
Object* accessor = get(component);
return accessor->IsTheHole() ? GetHeap()->undefined_value() : accessor;
}
Handle<DeoptimizationInputData> DeoptimizationInputData::New(
Isolate* isolate, int deopt_entry_count, PretenureFlag pretenure) {
DCHECK(deopt_entry_count > 0);
return Handle<DeoptimizationInputData>::cast(
isolate->factory()->NewFixedArray(LengthFor(deopt_entry_count),
pretenure));
}
Handle<DeoptimizationOutputData> DeoptimizationOutputData::New(
Isolate* isolate,
int number_of_deopt_points,
PretenureFlag pretenure) {
Handle<FixedArray> result;
if (number_of_deopt_points == 0) {
result = isolate->factory()->empty_fixed_array();
} else {
result = isolate->factory()->NewFixedArray(
LengthOfFixedArray(number_of_deopt_points), pretenure);
}
return Handle<DeoptimizationOutputData>::cast(result);
}
#ifdef DEBUG
bool DescriptorArray::IsEqualTo(DescriptorArray* other) {
if (IsEmpty()) return other->IsEmpty();
if (other->IsEmpty()) return false;
if (length() != other->length()) return false;
for (int i = 0; i < length(); ++i) {
if (get(i) != other->get(i)) return false;
}
return true;
}
#endif
bool String::LooksValid() {
if (!GetIsolate()->heap()->Contains(this)) return false;
return true;
}
String::FlatContent String::GetFlatContent() {
DCHECK(!AllowHeapAllocation::IsAllowed());
int length = this->length();
StringShape shape(this);
String* string = this;
int offset = 0;
if (shape.representation_tag() == kConsStringTag) {
ConsString* cons = ConsString::cast(string);
if (cons->second()->length() != 0) {
return FlatContent();
}
string = cons->first();
shape = StringShape(string);
}
if (shape.representation_tag() == kSlicedStringTag) {
SlicedString* slice = SlicedString::cast(string);
offset = slice->offset();
string = slice->parent();
shape = StringShape(string);
DCHECK(shape.representation_tag() != kConsStringTag &&
shape.representation_tag() != kSlicedStringTag);
}
if (shape.encoding_tag() == kOneByteStringTag) {
const uint8_t* start;
if (shape.representation_tag() == kSeqStringTag) {
start = SeqOneByteString::cast(string)->GetChars();
} else {
start = ExternalOneByteString::cast(string)->GetChars();
}
return FlatContent(start + offset, length);
} else {
DCHECK(shape.encoding_tag() == kTwoByteStringTag);
const uc16* start;
if (shape.representation_tag() == kSeqStringTag) {
start = SeqTwoByteString::cast(string)->GetChars();
} else {
start = ExternalTwoByteString::cast(string)->GetChars();
}
return FlatContent(start + offset, length);
}
}
SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
RobustnessFlag robust_flag,
int offset,
int length,
int* length_return) {
if (robust_flag == ROBUST_STRING_TRAVERSAL && !LooksValid()) {
return SmartArrayPointer<char>(NULL);
}
Heap* heap = GetHeap();
// Negative length means the to the end of the string.
if (length < 0) length = kMaxInt - offset;
// Compute the size of the UTF-8 string. Start at the specified offset.
Access<ConsStringIteratorOp> op(
heap->isolate()->objects_string_iterator());
StringCharacterStream stream(this, op.value(), offset);
int character_position = offset;
int utf8_bytes = 0;
int last = unibrow::Utf16::kNoPreviousCharacter;
while (stream.HasMore() && character_position++ < offset + length) {
uint16_t character = stream.GetNext();
utf8_bytes += unibrow::Utf8::Length(character, last);
last = character;
}
if (length_return) {
*length_return = utf8_bytes;
}
char* result = NewArray<char>(utf8_bytes + 1);
// Convert the UTF-16 string to a UTF-8 buffer. Start at the specified offset.
stream.Reset(this, offset);
character_position = offset;
int utf8_byte_position = 0;
last = unibrow::Utf16::kNoPreviousCharacter;
while (stream.HasMore() && character_position++ < offset + length) {
uint16_t character = stream.GetNext();
if (allow_nulls == DISALLOW_NULLS && character == 0) {
character = ' ';
}
utf8_byte_position +=
unibrow::Utf8::Encode(result + utf8_byte_position, character, last);
last = character;
}
result[utf8_byte_position] = 0;
return SmartArrayPointer<char>(result);
}
SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
RobustnessFlag robust_flag,
int* length_return) {
return ToCString(allow_nulls, robust_flag, 0, -1, length_return);
}
const uc16* String::GetTwoByteData(unsigned start) {
DCHECK(!IsOneByteRepresentationUnderneath());
switch (StringShape(this).representation_tag()) {
case kSeqStringTag:
return SeqTwoByteString::cast(this)->SeqTwoByteStringGetData(start);
case kExternalStringTag:
return ExternalTwoByteString::cast(this)->
ExternalTwoByteStringGetData(start);
case kSlicedStringTag: {
SlicedString* slice = SlicedString::cast(this);
return slice->parent()->GetTwoByteData(start + slice->offset());
}
case kConsStringTag:
UNREACHABLE();
return NULL;
}
UNREACHABLE();
return NULL;
}
SmartArrayPointer<uc16> String::ToWideCString(RobustnessFlag robust_flag) {
if (robust_flag == ROBUST_STRING_TRAVERSAL && !LooksValid()) {
return SmartArrayPointer<uc16>();
}
Heap* heap = GetHeap();
Access<ConsStringIteratorOp> op(
heap->isolate()->objects_string_iterator());
StringCharacterStream stream(this, op.value());
uc16* result = NewArray<uc16>(length() + 1);
int i = 0;
while (stream.HasMore()) {
uint16_t character = stream.GetNext();
result[i++] = character;
}
result[i] = 0;
return SmartArrayPointer<uc16>(result);
}
const uc16* SeqTwoByteString::SeqTwoByteStringGetData(unsigned start) {
return reinterpret_cast<uc16*>(
reinterpret_cast<char*>(this) - kHeapObjectTag + kHeaderSize) + start;
}
void Relocatable::PostGarbageCollectionProcessing(Isolate* isolate) {
Relocatable* current = isolate->relocatable_top();
while (current != NULL) {
current->PostGarbageCollection();
current = current->prev_;
}
}
// Reserve space for statics needing saving and restoring.
int Relocatable::ArchiveSpacePerThread() {
return sizeof(Relocatable*); // NOLINT
}
// Archive statics that are thread-local.
char* Relocatable::ArchiveState(Isolate* isolate, char* to) {
*reinterpret_cast<Relocatable**>(to) = isolate->relocatable_top();
isolate->set_relocatable_top(NULL);
return to + ArchiveSpacePerThread();
}
// Restore statics that are thread-local.
char* Relocatable::RestoreState(Isolate* isolate, char* from) {
isolate->set_relocatable_top(*reinterpret_cast<Relocatable**>(from));
return from + ArchiveSpacePerThread();
}
char* Relocatable::Iterate(ObjectVisitor* v, char* thread_storage) {
Relocatable* top = *reinterpret_cast<Relocatable**>(thread_storage);
Iterate(v, top);
return thread_storage + ArchiveSpacePerThread();
}
void Relocatable::Iterate(Isolate* isolate, ObjectVisitor* v) {
Iterate(v, isolate->relocatable_top());
}
void Relocatable::Iterate(ObjectVisitor* v, Relocatable* top) {
Relocatable* current = top;
while (current != NULL) {
current->IterateInstance(v);
current = current->prev_;
}
}
FlatStringReader::FlatStringReader(Isolate* isolate, Handle<String> str)
: Relocatable(isolate),
str_(str.location()),
length_(str->length()) {
PostGarbageCollection();
}
FlatStringReader::FlatStringReader(Isolate* isolate, Vector<const char> input)
: Relocatable(isolate),
str_(0),
is_one_byte_(true),
length_(input.length()),
start_(input.start()) {}
void FlatStringReader::PostGarbageCollection() {
if (str_ == NULL) return;
Handle<String> str(str_);
DCHECK(str->IsFlat());
DisallowHeapAllocation no_gc;
// This does not actually prevent the vector from being relocated later.
String::FlatContent content = str->GetFlatContent();
DCHECK(content.IsFlat());
is_one_byte_ = content.IsOneByte();
if (is_one_byte_) {
start_ = content.ToOneByteVector().start();
} else {
start_ = content.ToUC16Vector().start();
}
}
void ConsStringIteratorOp::Initialize(ConsString* cons_string, int offset) {
DCHECK(cons_string != NULL);
root_ = cons_string;
consumed_ = offset;
// Force stack blown condition to trigger restart.
depth_ = 1;
maximum_depth_ = kStackSize + depth_;
DCHECK(StackBlown());
}
String* ConsStringIteratorOp::Continue(int* offset_out) {
DCHECK(depth_ != 0);
DCHECK_EQ(0, *offset_out);
bool blew_stack = StackBlown();
String* string = NULL;
// Get the next leaf if there is one.
if (!blew_stack) string = NextLeaf(&blew_stack);
// Restart search from root.
if (blew_stack) {
DCHECK(string == NULL);
string = Search(offset_out);
}
// Ensure future calls return null immediately.
if (string == NULL) Reset(NULL);
return string;
}
String* ConsStringIteratorOp::Search(int* offset_out) {
ConsString* cons_string = root_;
// Reset the stack, pushing the root string.
depth_ = 1;
maximum_depth_ = 1;
frames_[0] = cons_string;
const int consumed = consumed_;
int offset = 0;
while (true) {
// Loop until the string is found which contains the target offset.
String* string = cons_string->first();
int length = string->length();
int32_t type;
if (consumed < offset + length) {
// Target offset is in the left branch.
// Keep going if we're still in a ConString.
type = string->map()->instance_type();
if ((type & kStringRepresentationMask) == kConsStringTag) {
cons_string = ConsString::cast(string);
PushLeft(cons_string);
continue;
}
// Tell the stack we're done descending.
AdjustMaximumDepth();
} else {
// Descend right.
// Update progress through the string.
offset += length;
// Keep going if we're still in a ConString.
string = cons_string->second();
type = string->map()->instance_type();
if ((type & kStringRepresentationMask) == kConsStringTag) {
cons_string = ConsString::cast(string);
PushRight(cons_string);
continue;
}
// Need this to be updated for the current string.
length = string->length();
// Account for the possibility of an empty right leaf.
// This happens only if we have asked for an offset outside the string.
if (length == 0) {
// Reset so future operations will return null immediately.
Reset(NULL);
return NULL;
}
// Tell the stack we're done descending.
AdjustMaximumDepth();
// Pop stack so next iteration is in correct place.
Pop();
}
DCHECK(length != 0);
// Adjust return values and exit.
consumed_ = offset + length;
*offset_out = consumed - offset;
return string;
}
UNREACHABLE();
return NULL;
}
String* ConsStringIteratorOp::NextLeaf(bool* blew_stack) {
while (true) {
// Tree traversal complete.
if (depth_ == 0) {
*blew_stack = false;
return NULL;
}
// We've lost track of higher nodes.
if (StackBlown()) {
*blew_stack = true;
return NULL;
}
// Go right.
ConsString* cons_string = frames_[OffsetForDepth(depth_ - 1)];
String* string = cons_string->second();
int32_t type = string->map()->instance_type();
if ((type & kStringRepresentationMask) != kConsStringTag) {
// Pop stack so next iteration is in correct place.
Pop();
int length = string->length();
// Could be a flattened ConsString.
if (length == 0) continue;
consumed_ += length;
return string;
}
cons_string = ConsString::cast(string);
PushRight(cons_string);
// Need to traverse all the way left.
while (true) {
// Continue left.
string = cons_string->first();
type = string->map()->instance_type();
if ((type & kStringRepresentationMask) != kConsStringTag) {
AdjustMaximumDepth();
int length = string->length();
DCHECK(length != 0);
consumed_ += length;
return string;
}
cons_string = ConsString::cast(string);
PushLeft(cons_string);
}
}
UNREACHABLE();
return NULL;
}
uint16_t ConsString::ConsStringGet(int index) {
DCHECK(index >= 0 && index < this->length());
// Check for a flattened cons string
if (second()->length() == 0) {
String* left = first();
return left->Get(index);
}
String* string = String::cast(this);
while (true) {
if (StringShape(string).IsCons()) {
ConsString* cons_string = ConsString::cast(string);
String* left = cons_string->first();
if (left->length() > index) {
string = left;
} else {
index -= left->length();
string = cons_string->second();
}
} else {
return string->Get(index);
}
}
UNREACHABLE();
return 0;
}
uint16_t SlicedString::SlicedStringGet(int index) {
return parent()->Get(offset() + index);
}
template <typename sinkchar>
void String::WriteToFlat(String* src,
sinkchar* sink,
int f,
int t) {
String* source = src;
int from = f;
int to = t;
while (true) {
DCHECK(0 <= from && from <= to && to <= source->length());
switch (StringShape(source).full_representation_tag()) {
case kOneByteStringTag | kExternalStringTag: {
CopyChars(sink, ExternalOneByteString::cast(source)->GetChars() + from,
to - from);
return;
}
case kTwoByteStringTag | kExternalStringTag: {
const uc16* data =
ExternalTwoByteString::cast(source)->GetChars();
CopyChars(sink,
data + from,
to - from);
return;
}
case kOneByteStringTag | kSeqStringTag: {
CopyChars(sink,
SeqOneByteString::cast(source)->GetChars() + from,
to - from);
return;
}
case kTwoByteStringTag | kSeqStringTag: {
CopyChars(sink,
SeqTwoByteString::cast(source)->GetChars() + from,
to - from);
return;
}
case kOneByteStringTag | kConsStringTag:
case kTwoByteStringTag | kConsStringTag: {
ConsString* cons_string = ConsString::cast(source);
String* first = cons_string->first();
int boundary = first->length();
if (to - boundary >= boundary - from) {
// Right hand side is longer. Recurse over left.
if (from < boundary) {
WriteToFlat(first, sink, from, boundary);
sink += boundary - from;
from = 0;
} else {
from -= boundary;
}
to -= boundary;
source = cons_string->second();
} else {
// Left hand side is longer. Recurse over right.
if (to > boundary) {
String* second = cons_string->second();
// When repeatedly appending to a string, we get a cons string that
// is unbalanced to the left, a list, essentially. We inline the
// common case of sequential one-byte right child.
if (to - boundary == 1) {
sink[boundary - from] = static_cast<sinkchar>(second->Get(0));
} else if (second->IsSeqOneByteString()) {
CopyChars(sink + boundary - from,
SeqOneByteString::cast(second)->GetChars(),
to - boundary);
} else {
WriteToFlat(second,
sink + boundary - from,
0,
to - boundary);
}
to = boundary;
}
source = first;
}
break;
}
case kOneByteStringTag | kSlicedStringTag:
case kTwoByteStringTag | kSlicedStringTag: {
SlicedString* slice = SlicedString::cast(source);
unsigned offset = slice->offset();
WriteToFlat(slice->parent(), sink, from + offset, to + offset);
return;
}
}
}
}
template <typename SourceChar>
static void CalculateLineEndsImpl(Isolate* isolate,
List<int>* line_ends,
Vector<const SourceChar> src,
bool include_ending_line) {
const int src_len = src.length();
StringSearch<uint8_t, SourceChar> search(isolate, STATIC_CHAR_VECTOR("\n"));
// Find and record line ends.
int position = 0;
while (position != -1 && position < src_len) {
position = search.Search(src, position);
if (position != -1) {
line_ends->Add(position);
position++;
} else if (include_ending_line) {
// Even if the last line misses a line end, it is counted.
line_ends->Add(src_len);
return;
}
}
}
Handle<FixedArray> String::CalculateLineEnds(Handle<String> src,
bool include_ending_line) {
src = Flatten(src);
// Rough estimate of line count based on a roughly estimated average
// length of (unpacked) code.
int line_count_estimate = src->length() >> 4;
List<int> line_ends(line_count_estimate);
Isolate* isolate = src->GetIsolate();
{ DisallowHeapAllocation no_allocation; // ensure vectors stay valid.
// Dispatch on type of strings.
String::FlatContent content = src->GetFlatContent();
DCHECK(content.IsFlat());
if (content.IsOneByte()) {
CalculateLineEndsImpl(isolate,
&line_ends,
content.ToOneByteVector(),
include_ending_line);
} else {
CalculateLineEndsImpl(isolate,
&line_ends,
content.ToUC16Vector(),
include_ending_line);
}
}
int line_count = line_ends.length();
Handle<FixedArray> array = isolate->factory()->NewFixedArray(line_count);
for (int i = 0; i < line_count; i++) {
array->set(i, Smi::FromInt(line_ends[i]));
}
return array;
}
// Compares the contents of two strings by reading and comparing
// int-sized blocks of characters.
template <typename Char>
static inline bool CompareRawStringContents(const Char* const a,
const Char* const b,
int length) {
return CompareChars(a, b, length) == 0;
}
template<typename Chars1, typename Chars2>
class RawStringComparator : public AllStatic {
public:
static inline bool compare(const Chars1* a, const Chars2* b, int len) {
DCHECK(sizeof(Chars1) != sizeof(Chars2));
for (int i = 0; i < len; i++) {
if (a[i] != b[i]) {
return false;
}
}
return true;
}
};
template<>
class RawStringComparator<uint16_t, uint16_t> {
public:
static inline bool compare(const uint16_t* a, const uint16_t* b, int len) {
return CompareRawStringContents(a, b, len);
}
};
template<>
class RawStringComparator<uint8_t, uint8_t> {
public:
static inline bool compare(const uint8_t* a, const uint8_t* b, int len) {
return CompareRawStringContents(a, b, len);
}
};
class StringComparator {
class State {
public:
explicit inline State(ConsStringIteratorOp* op)
: op_(op), is_one_byte_(true), length_(0), buffer8_(NULL) {}
inline void Init(String* string) {
ConsString* cons_string = String::VisitFlat(this, string);
op_->Reset(cons_string);
if (cons_string != NULL) {
int offset;
string = op_->Next(&offset);
String::VisitFlat(this, string, offset);
}
}
inline void VisitOneByteString(const uint8_t* chars, int length) {
is_one_byte_ = true;
buffer8_ = chars;
length_ = length;
}
inline void VisitTwoByteString(const uint16_t* chars, int length) {
is_one_byte_ = false;
buffer16_ = chars;
length_ = length;
}
void Advance(int consumed) {
DCHECK(consumed <= length_);
// Still in buffer.
if (length_ != consumed) {
if (is_one_byte_) {
buffer8_ += consumed;
} else {
buffer16_ += consumed;
}
length_ -= consumed;
return;
}
// Advance state.
int offset;
String* next = op_->Next(&offset);
DCHECK_EQ(0, offset);
DCHECK(next != NULL);
String::VisitFlat(this, next);
}
ConsStringIteratorOp* const op_;
bool is_one_byte_;
int length_;
union {
const uint8_t* buffer8_;
const uint16_t* buffer16_;
};
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(State);
};
public:
inline StringComparator(ConsStringIteratorOp* op_1,
ConsStringIteratorOp* op_2)
: state_1_(op_1),
state_2_(op_2) {
}
template<typename Chars1, typename Chars2>
static inline bool Equals(State* state_1, State* state_2, int to_check) {
const Chars1* a = reinterpret_cast<const Chars1*>(state_1->buffer8_);
const Chars2* b = reinterpret_cast<const Chars2*>(state_2->buffer8_);
return RawStringComparator<Chars1, Chars2>::compare(a, b, to_check);
}
bool Equals(String* string_1, String* string_2) {
int length = string_1->length();
state_1_.Init(string_1);
state_2_.Init(string_2);
while (true) {
int to_check = Min(state_1_.length_, state_2_.length_);
DCHECK(to_check > 0 && to_check <= length);
bool is_equal;
if (state_1_.is_one_byte_) {
if (state_2_.is_one_byte_) {
is_equal = Equals<uint8_t, uint8_t>(&state_1_, &state_2_, to_check);
} else {
is_equal = Equals<uint8_t, uint16_t>(&state_1_, &state_2_, to_check);
}
} else {
if (state_2_.is_one_byte_) {
is_equal = Equals<uint16_t, uint8_t>(&state_1_, &state_2_, to_check);
} else {
is_equal = Equals<uint16_t, uint16_t>(&state_1_, &state_2_, to_check);
}
}
// Looping done.
if (!is_equal) return false;
length -= to_check;
// Exit condition. Strings are equal.
if (length == 0) return true;
state_1_.Advance(to_check);
state_2_.Advance(to_check);
}
}
private:
State state_1_;
State state_2_;
DISALLOW_IMPLICIT_CONSTRUCTORS(StringComparator);
};
bool String::SlowEquals(String* other) {
DisallowHeapAllocation no_gc;
// Fast check: negative check with lengths.
int len = length();
if (len != other->length()) return false;
if (len == 0) return true;
// Fast check: if hash code is computed for both strings
// a fast negative check can be performed.
if (HasHashCode() && other->HasHashCode()) {
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
if (Hash() != other->Hash()) {
bool found_difference = false;
for (int i = 0; i < len; i++) {
if (Get(i) != other->Get(i)) {
found_difference = true;
break;
}
}
DCHECK(found_difference);
}
}
#endif
if (Hash() != other->Hash()) return false;
}
// We know the strings are both non-empty. Compare the first chars
// before we try to flatten the strings.
if (this->Get(0) != other->Get(0)) return false;
if (IsSeqOneByteString() && other->IsSeqOneByteString()) {
const uint8_t* str1 = SeqOneByteString::cast(this)->GetChars();
const uint8_t* str2 = SeqOneByteString::cast(other)->GetChars();
return CompareRawStringContents(str1, str2, len);
}
Isolate* isolate = GetIsolate();
StringComparator comparator(isolate->objects_string_compare_iterator_a(),
isolate->objects_string_compare_iterator_b());
return comparator.Equals(this, other);
}
bool String::SlowEquals(Handle<String> one, Handle<String> two) {
// Fast check: negative check with lengths.
int one_length = one->length();
if (one_length != two->length()) return false;
if (one_length == 0) return true;
// Fast check: if hash code is computed for both strings
// a fast negative check can be performed.
if (one->HasHashCode() && two->HasHashCode()) {
#ifdef ENABLE_SLOW_DCHECKS
if (FLAG_enable_slow_asserts) {
if (one->Hash() != two->Hash()) {
bool found_difference = false;
for (int i = 0; i < one_length; i++) {
if (one->Get(i) != two->Get(i)) {
found_difference = true;
break;
}
}
DCHECK(found_difference);
}
}
#endif
if (one->Hash() != two->Hash()) return false;
}
// We know the strings are both non-empty. Compare the first chars
// before we try to flatten the strings.
if (one->Get(0) != two->Get(0)) return false;
one = String::Flatten(one);
two = String::Flatten(two);
DisallowHeapAllocation no_gc;
String::FlatContent flat1 = one->GetFlatContent();
String::FlatContent flat2 = two->GetFlatContent();
if (flat1.IsOneByte() && flat2.IsOneByte()) {
return CompareRawStringContents(flat1.ToOneByteVector().start(),
flat2.ToOneByteVector().start(),
one_length);
} else {
for (int i = 0; i < one_length; i++) {
if (flat1.Get(i) != flat2.Get(i)) return false;
}
return true;
}
}
bool String::MarkAsUndetectable() {
if (StringShape(this).IsInternalized()) return false;
Map* map = this->map();
Heap* heap = GetHeap();
if (map == heap->string_map()) {
this->set_map(heap->undetectable_string_map());
return true;
} else if (map == heap->one_byte_string_map()) {
this->set_map(heap->undetectable_one_byte_string_map());
return true;
}
// Rest cannot be marked as undetectable
return false;
}
bool String::IsUtf8EqualTo(Vector<const char> str, bool allow_prefix_match) {
int slen = length();
// Can't check exact length equality, but we can check bounds.
int str_len = str.length();
if (!allow_prefix_match &&
(str_len < slen ||
str_len > slen*static_cast<int>(unibrow::Utf8::kMaxEncodedSize))) {
return false;
}
int i;
unsigned remaining_in_str = static_cast<unsigned>(str_len);
const uint8_t* utf8_data = reinterpret_cast<const uint8_t*>(str.start());
for (i = 0; i < slen && remaining_in_str > 0; i++) {
unsigned cursor = 0;
uint32_t r = unibrow::Utf8::ValueOf(utf8_data, remaining_in_str, &cursor);
DCHECK(cursor > 0 && cursor <= remaining_in_str);
if (r > unibrow::Utf16::kMaxNonSurrogateCharCode) {
if (i > slen - 1) return false;
if (Get(i++) != unibrow::Utf16::LeadSurrogate(r)) return false;
if (Get(i) != unibrow::Utf16::TrailSurrogate(r)) return false;
} else {
if (Get(i) != r) return false;
}
utf8_data += cursor;
remaining_in_str -= cursor;
}
return (allow_prefix_match || i == slen) && remaining_in_str == 0;
}
bool String::IsOneByteEqualTo(Vector<const uint8_t> str) {
int slen = length();
if (str.length() != slen) return false;
DisallowHeapAllocation no_gc;
FlatContent content = GetFlatContent();
if (content.IsOneByte()) {
return CompareChars(content.ToOneByteVector().start(),
str.start(), slen) == 0;
}
for (int i = 0; i < slen; i++) {
if (Get(i) != static_cast<uint16_t>(str[i])) return false;
}
return true;
}
bool String::IsTwoByteEqualTo(Vector<const uc16> str) {
int slen = length();
if (str.length() != slen) return false;
DisallowHeapAllocation no_gc;
FlatContent content = GetFlatContent();
if (content.IsTwoByte()) {
return CompareChars(content.ToUC16Vector().start(), str.start(), slen) == 0;
}
for (int i = 0; i < slen; i++) {
if (Get(i) != str[i]) return false;
}
return true;
}
uint32_t String::ComputeAndSetHash() {
// Should only be called if hash code has not yet been computed.
DCHECK(!HasHashCode());
// Store the hash code in the object.
uint32_t field = IteratingStringHasher::Hash(this, GetHeap()->HashSeed());
set_hash_field(field);
// Check the hash code is there.
DCHECK(HasHashCode());
uint32_t result = field >> kHashShift;
DCHECK(result != 0); // Ensure that the hash value of 0 is never computed.
return result;
}
bool String::ComputeArrayIndex(uint32_t* index) {
int length = this->length();
if (length == 0 || length > kMaxArrayIndexSize) return false;
ConsStringIteratorOp op;
StringCharacterStream stream(this, &op);
return StringToArrayIndex(&stream, index);
}
bool String::SlowAsArrayIndex(uint32_t* index) {
if (length() <= kMaxCachedArrayIndexLength) {
Hash(); // force computation of hash code
uint32_t field = hash_field();
if ((field & kIsNotArrayIndexMask) != 0) return false;
// Isolate the array index form the full hash field.
*index = ArrayIndexValueBits::decode(field);
return true;
} else {
return ComputeArrayIndex(index);
}
}
Handle<String> SeqString::Truncate(Handle<SeqString> string, int new_length) {
int new_size, old_size;
int old_length = string->length();
if (old_length <= new_length) return string;
if (string->IsSeqOneByteString()) {
old_size = SeqOneByteString::SizeFor(old_length);
new_size = SeqOneByteString::SizeFor(new_length);
} else {
DCHECK(string->IsSeqTwoByteString());
old_size = SeqTwoByteString::SizeFor(old_length);
new_size = SeqTwoByteString::SizeFor(new_length);
}
int delta = old_size - new_size;
Address start_of_string = string->address();
DCHECK_OBJECT_ALIGNED(start_of_string);
DCHECK_OBJECT_ALIGNED(start_of_string + new_size);
Heap* heap = string->GetHeap();
NewSpace* newspace = heap->new_space();
if (newspace->Contains(start_of_string) &&
newspace->top() == start_of_string + old_size) {
// Last allocated object in new space. Simply lower allocation top.
newspace->set_top(start_of_string + new_size);
} else {
// Sizes are pointer size aligned, so that we can use filler objects
// that are a multiple of pointer size.
heap->CreateFillerObjectAt(start_of_string + new_size, delta);
}
heap->AdjustLiveBytes(start_of_string, -delta, Heap::FROM_MUTATOR);
// We are storing the new length using release store after creating a filler
// for the left-over space to avoid races with the sweeper thread.
string->synchronized_set_length(new_length);
if (new_length == 0) return heap->isolate()->factory()->empty_string();
return string;
}
uint32_t StringHasher::MakeArrayIndexHash(uint32_t value, int length) {
// For array indexes mix the length into the hash as an array index could
// be zero.
DCHECK(length > 0);
DCHECK(length <= String::kMaxArrayIndexSize);
DCHECK(TenToThe(String::kMaxCachedArrayIndexLength) <
(1 << String::kArrayIndexValueBits));
value <<= String::ArrayIndexValueBits::kShift;
value |= length << String::ArrayIndexLengthBits::kShift;
DCHECK((value & String::kIsNotArrayIndexMask) == 0);
DCHECK((length > String::kMaxCachedArrayIndexLength) ||
(value & String::kContainsCachedArrayIndexMask) == 0);
return value;
}
uint32_t StringHasher::GetHashField() {
if (length_ <= String::kMaxHashCalcLength) {
if (is_array_index_) {
return MakeArrayIndexHash(array_index_, length_);
}
return (GetHashCore(raw_running_hash_) << String::kHashShift) |
String::kIsNotArrayIndexMask;
} else {
return (length_ << String::kHashShift) | String::kIsNotArrayIndexMask;
}
}
uint32_t StringHasher::ComputeUtf8Hash(Vector<const char> chars,
uint32_t seed,
int* utf16_length_out) {
int vector_length = chars.length();
// Handle some edge cases
if (vector_length <= 1) {
DCHECK(vector_length == 0 ||
static_cast<uint8_t>(chars.start()[0]) <=
unibrow::Utf8::kMaxOneByteChar);
*utf16_length_out = vector_length;
return HashSequentialString(chars.start(), vector_length, seed);
}
// Start with a fake length which won't affect computation.
// It will be updated later.
StringHasher hasher(String::kMaxArrayIndexSize, seed);
unsigned remaining = static_cast<unsigned>(vector_length);
const uint8_t* stream = reinterpret_cast<const uint8_t*>(chars.start());
int utf16_length = 0;
bool is_index = true;
DCHECK(hasher.is_array_index_);
while (remaining > 0) {
unsigned consumed = 0;
uint32_t c = unibrow::Utf8::ValueOf(stream, remaining, &consumed);
DCHECK(consumed > 0 && consumed <= remaining);
stream += consumed;
remaining -= consumed;
bool is_two_characters = c > unibrow::Utf16::kMaxNonSurrogateCharCode;
utf16_length += is_two_characters ? 2 : 1;
// No need to keep hashing. But we do need to calculate utf16_length.
if (utf16_length > String::kMaxHashCalcLength) continue;
if (is_two_characters) {
uint16_t c1 = unibrow::Utf16::LeadSurrogate(c);
uint16_t c2 = unibrow::Utf16::TrailSurrogate(c);
hasher.AddCharacter(c1);
hasher.AddCharacter(c2);
if (is_index) is_index = hasher.UpdateIndex(c1);
if (is_index) is_index = hasher.UpdateIndex(c2);
} else {
hasher.AddCharacter(c);
if (is_index) is_index = hasher.UpdateIndex(c);
}
}
*utf16_length_out = static_cast<int>(utf16_length);
// Must set length here so that hash computation is correct.
hasher.length_ = utf16_length;
return hasher.GetHashField();
}
void String::PrintOn(FILE* file) {
int length = this->length();
for (int i = 0; i < length; i++) {
PrintF(file, "%c", Get(i));
}
}
int Map::Hash() {
// For performance reasons we only hash the 3 most variable fields of a map:
// constructor, prototype and bit_field2.
// Shift away the tag.
int hash = (static_cast<uint32_t>(
reinterpret_cast<uintptr_t>(constructor())) >> 2);
// XOR-ing the prototype and constructor directly yields too many zero bits
// when the two pointers are close (which is fairly common).
// To avoid this we shift the prototype 4 bits relatively to the constructor.
hash ^= (static_cast<uint32_t>(
reinterpret_cast<uintptr_t>(prototype())) << 2);
return hash ^ (hash >> 16) ^ bit_field2();
}
static bool CheckEquivalent(Map* first, Map* second) {
return
first->constructor() == second->constructor() &&
first->prototype() == second->prototype() &&
first->instance_type() == second->instance_type() &&
first->bit_field() == second->bit_field() &&
first->bit_field2() == second->bit_field2() &&
first->is_frozen() == second->is_frozen() &&
first->has_instance_call_handler() == second->has_instance_call_handler();
}
bool Map::EquivalentToForTransition(Map* other) {
return CheckEquivalent(this, other);
}
bool Map::EquivalentToForNormalization(Map* other,
PropertyNormalizationMode mode) {
int properties = mode == CLEAR_INOBJECT_PROPERTIES
? 0 : other->inobject_properties();
return CheckEquivalent(this, other) && inobject_properties() == properties;
}
void ConstantPoolArray::ConstantPoolIterateBody(ObjectVisitor* v) {
// Unfortunately the serializer relies on pointers within an object being
// visited in-order, so we have to iterate both the code and heap pointers in
// the small section before doing so in the extended section.
for (int s = 0; s <= final_section(); ++s) {
LayoutSection section = static_cast<LayoutSection>(s);
ConstantPoolArray::Iterator code_iter(this, ConstantPoolArray::CODE_PTR,
section);
while (!code_iter.is_finished()) {
v->VisitCodeEntry(reinterpret_cast<Address>(
RawFieldOfElementAt(code_iter.next_index())));
}
ConstantPoolArray::Iterator heap_iter(this, ConstantPoolArray::HEAP_PTR,
section);
while (!heap_iter.is_finished()) {
v->VisitPointer(RawFieldOfElementAt(heap_iter.next_index()));
}
}
}
void ConstantPoolArray::ClearPtrEntries(Isolate* isolate) {
Type type[] = { CODE_PTR, HEAP_PTR };
Address default_value[] = {
isolate->builtins()->builtin(Builtins::kIllegal)->entry(),
reinterpret_cast<Address>(isolate->heap()->undefined_value()) };
for (int i = 0; i < 2; ++i) {
for (int s = 0; s <= final_section(); ++s) {
LayoutSection section = static_cast<LayoutSection>(s);
if (number_of_entries(type[i], section) > 0) {
int offset = OffsetOfElementAt(first_index(type[i], section));
MemsetPointer(
reinterpret_cast<Address*>(HeapObject::RawField(this, offset)),
default_value[i],
number_of_entries(type[i], section));
}
}
}
}
void JSFunction::JSFunctionIterateBody(int object_size, ObjectVisitor* v) {
// Iterate over all fields in the body but take care in dealing with
// the code entry.
IteratePointers(v, kPropertiesOffset, kCodeEntryOffset);
v->VisitCodeEntry(this->address() + kCodeEntryOffset);
IteratePointers(v, kCodeEntryOffset + kPointerSize, object_size);
}
void JSFunction::MarkForOptimization() {
DCHECK(!IsOptimized());
DCHECK(shared()->allows_lazy_compilation() ||
code()->optimizable());
DCHECK(!shared()->is_generator());
set_code_no_write_barrier(
GetIsolate()->builtins()->builtin(Builtins::kCompileOptimized));
// No write barrier required, since the builtin is part of the root set.
}
void JSFunction::MarkForConcurrentOptimization() {
DCHECK(is_compiled() || GetIsolate()->DebuggerHasBreakPoints());
DCHECK(!IsOptimized());
DCHECK(shared()->allows_lazy_compilation() || code()->optimizable());
DCHECK(!shared()->is_generator());
DCHECK(GetIsolate()->concurrent_recompilation_enabled());
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Marking ");
ShortPrint();
PrintF(" for concurrent recompilation.\n");
}
set_code_no_write_barrier(
GetIsolate()->builtins()->builtin(Builtins::kCompileOptimizedConcurrent));
// No write barrier required, since the builtin is part of the root set.
}
void JSFunction::MarkInOptimizationQueue() {
// We can only arrive here via the concurrent-recompilation builtin. If
// break points were set, the code would point to the lazy-compile builtin.
DCHECK(!GetIsolate()->DebuggerHasBreakPoints());
DCHECK(IsMarkedForConcurrentOptimization() && !IsOptimized());
DCHECK(shared()->allows_lazy_compilation() || code()->optimizable());
DCHECK(GetIsolate()->concurrent_recompilation_enabled());
if (FLAG_trace_concurrent_recompilation) {
PrintF(" ** Queueing ");
ShortPrint();
PrintF(" for concurrent recompilation.\n");
}
set_code_no_write_barrier(
GetIsolate()->builtins()->builtin(Builtins::kInOptimizationQueue));
// No write barrier required, since the builtin is part of the root set.
}
Handle<JSFunction> JSFunction::CloneClosure(Handle<JSFunction> function) {
Isolate* isolate = function->GetIsolate();
Handle<Map> map(function->map());
Handle<SharedFunctionInfo> shared(function->shared());
Handle<Context> context(function->context());
Handle<JSFunction> clone =
isolate->factory()->NewFunctionFromSharedFunctionInfo(shared, context);
if (shared->bound()) {
clone->set_function_bindings(function->function_bindings());
}
// In typical case, __proto__ of ``function`` is the default Function
// prototype, which means that SetPrototype below is a no-op.
// In rare cases when that is not true, we mutate the clone's __proto__.
Handle<Object> original_prototype(map->prototype(), isolate);
if (*original_prototype != clone->map()->prototype()) {
JSObject::SetPrototype(clone, original_prototype, false).Assert();
}
return clone;
}
void SharedFunctionInfo::AddToOptimizedCodeMap(
Handle<SharedFunctionInfo> shared,
Handle<Context> native_context,
Handle<Code> code,
Handle<FixedArray> literals,
BailoutId osr_ast_id) {
Isolate* isolate = shared->GetIsolate();
DCHECK(code->kind() == Code::OPTIMIZED_FUNCTION);
DCHECK(native_context->IsNativeContext());
STATIC_ASSERT(kEntryLength == 4);
Handle<FixedArray> new_code_map;
Handle<Object> value(shared->optimized_code_map(), isolate);
int old_length;
if (value->IsSmi()) {
// No optimized code map.
DCHECK_EQ(0, Smi::cast(*value)->value());
// Create 3 entries per context {context, code, literals}.
new_code_map = isolate->factory()->NewFixedArray(kInitialLength);
old_length = kEntriesStart;
} else {
// Copy old map and append one new entry.
Handle<FixedArray> old_code_map = Handle<FixedArray>::cast(value);
DCHECK_EQ(-1, shared->SearchOptimizedCodeMap(*native_context, osr_ast_id));
old_length = old_code_map->length();
new_code_map = FixedArray::CopySize(
old_code_map, old_length + kEntryLength);
// Zap the old map for the sake of the heap verifier.
if (Heap::ShouldZapGarbage()) {
Object** data = old_code_map->data_start();
MemsetPointer(data, isolate->heap()->the_hole_value(), old_length);
}
}
new_code_map->set(old_length + kContextOffset, *native_context);
new_code_map->set(old_length + kCachedCodeOffset, *code);
new_code_map->set(old_length + kLiteralsOffset, *literals);
new_code_map->set(old_length + kOsrAstIdOffset,
Smi::FromInt(osr_ast_id.ToInt()));
#ifdef DEBUG
for (int i = kEntriesStart; i < new_code_map->length(); i += kEntryLength) {
DCHECK(new_code_map->get(i + kContextOffset)->IsNativeContext());
DCHECK(new_code_map->get(i + kCachedCodeOffset)->IsCode());
DCHECK(Code::cast(new_code_map->get(i + kCachedCodeOffset))->kind() ==
Code::OPTIMIZED_FUNCTION);
DCHECK(new_code_map->get(i + kLiteralsOffset)->IsFixedArray());
DCHECK(new_code_map->get(i + kOsrAstIdOffset)->IsSmi());
}
#endif
shared->set_optimized_code_map(*new_code_map);
}
FixedArray* SharedFunctionInfo::GetLiteralsFromOptimizedCodeMap(int index) {
DCHECK(index > kEntriesStart);
FixedArray* code_map = FixedArray::cast(optimized_code_map());
if (!bound()) {
FixedArray* cached_literals = FixedArray::cast(code_map->get(index + 1));
DCHECK_NE(NULL, cached_literals);
return cached_literals;
}
return NULL;
}
Code* SharedFunctionInfo::GetCodeFromOptimizedCodeMap(int index) {
DCHECK(index > kEntriesStart);
FixedArray* code_map = FixedArray::cast(optimized_code_map());
Code* code = Code::cast(code_map->get(index));
DCHECK_NE(NULL, code);
return code;
}
void SharedFunctionInfo::ClearOptimizedCodeMap() {
FixedArray* code_map = FixedArray::cast(optimized_code_map());
// If the next map link slot is already used then the function was
// enqueued with code flushing and we remove it now.
if (!code_map->get(kNextMapIndex)->IsUndefined()) {
CodeFlusher* flusher = GetHeap()->mark_compact_collector()->code_flusher();
flusher->EvictOptimizedCodeMap(this);
}
DCHECK(code_map->get(kNextMapIndex)->IsUndefined());
set_optimized_code_map(Smi::FromInt(0));
}
void SharedFunctionInfo::EvictFromOptimizedCodeMap(Code* optimized_code,
const char* reason) {
DisallowHeapAllocation no_gc;
if (optimized_code_map()->IsSmi()) return;
FixedArray* code_map = FixedArray::cast(optimized_code_map());
int dst = kEntriesStart;
int length = code_map->length();
for (int src = kEntriesStart; src < length; src += kEntryLength) {
DCHECK(code_map->get(src)->IsNativeContext());
if (Code::cast(code_map->get(src + kCachedCodeOffset)) == optimized_code) {
// Evict the src entry by not copying it to the dst entry.
if (FLAG_trace_opt) {
PrintF("[evicting entry from optimizing code map (%s) for ", reason);
ShortPrint();
BailoutId osr(Smi::cast(code_map->get(src + kOsrAstIdOffset))->value());
if (osr.IsNone()) {
PrintF("]\n");
} else {
PrintF(" (osr ast id %d)]\n", osr.ToInt());
}
}
} else {
// Keep the src entry by copying it to the dst entry.
if (dst != src) {
code_map->set(dst + kContextOffset,
code_map->get(src + kContextOffset));
code_map->set(dst + kCachedCodeOffset,
code_map->get(src + kCachedCodeOffset));
code_map->set(dst + kLiteralsOffset,
code_map->get(src + kLiteralsOffset));
code_map->set(dst + kOsrAstIdOffset,
code_map->get(src + kOsrAstIdOffset));
}
dst += kEntryLength;
}
}
if (dst != length) {
// Always trim even when array is cleared because of heap verifier.
GetHeap()->RightTrimFixedArray<Heap::FROM_MUTATOR>(code_map, length - dst);
if (code_map->length() == kEntriesStart) ClearOptimizedCodeMap();
}
}
void SharedFunctionInfo::TrimOptimizedCodeMap(int shrink_by) {
FixedArray* code_map = FixedArray::cast(optimized_code_map());
DCHECK(shrink_by % kEntryLength == 0);
DCHECK(shrink_by <= code_map->length() - kEntriesStart);
// Always trim even when array is cleared because of heap verifier.
GetHeap()->RightTrimFixedArray<Heap::FROM_GC>(code_map, shrink_by);
if (code_map->length() == kEntriesStart) {
ClearOptimizedCodeMap();
}
}
void JSObject::OptimizeAsPrototype(Handle<JSObject> object,
PrototypeOptimizationMode mode) {
if (object->IsGlobalObject()) return;
if (object->IsJSGlobalProxy()) return;
if (mode == FAST_PROTOTYPE && !object->map()->is_prototype_map()) {
// First normalize to ensure all JSFunctions are CONSTANT.
JSObject::NormalizeProperties(object, KEEP_INOBJECT_PROPERTIES, 0);
}
if (!object->HasFastProperties()) {
JSObject::MigrateSlowToFast(object, 0);
}
if (mode == FAST_PROTOTYPE && object->HasFastProperties() &&
!object->map()->is_prototype_map()) {
Handle<Map> new_map = Map::Copy(handle(object->map()));
JSObject::MigrateToMap(object, new_map);
object->map()->set_is_prototype_map(true);
}
}
void JSObject::ReoptimizeIfPrototype(Handle<JSObject> object) {
if (!object->map()->is_prototype_map()) return;
OptimizeAsPrototype(object, FAST_PROTOTYPE);
}
Handle<Object> CacheInitialJSArrayMaps(
Handle<Context> native_context, Handle<Map> initial_map) {
// Replace all of the cached initial array maps in the native context with
// the appropriate transitioned elements kind maps.
Factory* factory = native_context->GetIsolate()->factory();
Handle<FixedArray> maps = factory->NewFixedArrayWithHoles(
kElementsKindCount, TENURED);
Handle<Map> current_map = initial_map;
ElementsKind kind = current_map->elements_kind();
DCHECK(kind == GetInitialFastElementsKind());
maps->set(kind, *current_map);
for (int i = GetSequenceIndexFromFastElementsKind(kind) + 1;
i < kFastElementsKindCount; ++i) {
Handle<Map> new_map;
ElementsKind next_kind = GetFastElementsKindFromSequenceIndex(i);
if (current_map->HasElementsTransition()) {
new_map = handle(current_map->elements_transition_map());
DCHECK(new_map->elements_kind() == next_kind);
} else {
new_map = Map::CopyAsElementsKind(
current_map, next_kind, INSERT_TRANSITION);
}
maps->set(next_kind, *new_map);
current_map = new_map;
}
native_context->set_js_array_maps(*maps);
return initial_map;
}
void JSFunction::SetInstancePrototype(Handle<JSFunction> function,
Handle<Object> value) {
Isolate* isolate = function->GetIsolate();
DCHECK(value->IsJSReceiver());
// Now some logic for the maps of the objects that are created by using this
// function as a constructor.
if (function->has_initial_map()) {
// If the function has allocated the initial map replace it with a
// copy containing the new prototype. Also complete any in-object
// slack tracking that is in progress at this point because it is
// still tracking the old copy.
if (function->IsInobjectSlackTrackingInProgress()) {
function->CompleteInobjectSlackTracking();
}
Handle<Map> initial_map(function->initial_map(), isolate);
if (!initial_map->GetIsolate()->bootstrapper()->IsActive() &&
initial_map->instance_type() == JS_OBJECT_TYPE) {
// Put the value in the initial map field until an initial map is needed.
// At that point, a new initial map is created and the prototype is put
// into the initial map where it belongs.
function->set_prototype_or_initial_map(*value);
} else {
Handle<Map> new_map = Map::Copy(initial_map);
JSFunction::SetInitialMap(function, new_map, value);
// If the function is used as the global Array function, cache the
// initial map (and transitioned versions) in the native context.
Context* native_context = function->context()->native_context();
Object* array_function =
native_context->get(Context::ARRAY_FUNCTION_INDEX);
if (array_function->IsJSFunction() &&
*function == JSFunction::cast(array_function)) {
CacheInitialJSArrayMaps(handle(native_context, isolate), new_map);
}
}
// Deoptimize all code that embeds the previous initial map.
initial_map->dependent_code()->DeoptimizeDependentCodeGroup(
isolate, DependentCode::kInitialMapChangedGroup);
} else {
// Put the value in the initial map field until an initial map is
// needed. At that point, a new initial map is created and the
// prototype is put into the initial map where it belongs.
function->set_prototype_or_initial_map(*value);
}
isolate->heap()->ClearInstanceofCache();
}
void JSFunction::SetPrototype(Handle<JSFunction> function,
Handle<Object> value) {
DCHECK(function->should_have_prototype());
Handle<Object> construct_prototype = value;
// If the value is not a JSReceiver, store the value in the map's
// constructor field so it can be accessed. Also, set the prototype
// used for constructing objects to the original object prototype.
// See ECMA-262 13.2.2.
if (!value->IsJSReceiver()) {
// Copy the map so this does not affect unrelated functions.
// Remove map transitions because they point to maps with a
// different prototype.
Handle<Map> new_map = Map::Copy(handle(function->map()));
JSObject::MigrateToMap(function, new_map);
new_map->set_constructor(*value);
new_map->set_non_instance_prototype(true);
Isolate* isolate = new_map->GetIsolate();
construct_prototype = handle(
isolate->context()->native_context()->initial_object_prototype(),
isolate);
} else {
function->map()->set_non_instance_prototype(false);
}
return SetInstancePrototype(function, construct_prototype);
}
bool JSFunction::RemovePrototype() {
Context* native_context = context()->native_context();
Map* no_prototype_map = shared()->strict_mode() == SLOPPY
? native_context->sloppy_function_without_prototype_map()
: native_context->strict_function_without_prototype_map();
if (map() == no_prototype_map) return true;
#ifdef DEBUG
if (map() != (shared()->strict_mode() == SLOPPY
? native_context->sloppy_function_map()
: native_context->strict_function_map())) {
return false;
}
#endif
set_map(no_prototype_map);
set_prototype_or_initial_map(no_prototype_map->GetHeap()->the_hole_value());
return true;
}
void JSFunction::SetInitialMap(Handle<JSFunction> function, Handle<Map> map,
Handle<Object> prototype) {
if (prototype->IsJSObject()) {
Handle<JSObject> js_proto = Handle<JSObject>::cast(prototype);
JSObject::OptimizeAsPrototype(js_proto, FAST_PROTOTYPE);
}
map->set_prototype(*prototype);
function->set_prototype_or_initial_map(*map);
map->set_constructor(*function);
}
void JSFunction::EnsureHasInitialMap(Handle<JSFunction> function) {
if (function->has_initial_map()) return;
Isolate* isolate = function->GetIsolate();
// First create a new map with the size and number of in-object properties
// suggested by the function.
InstanceType instance_type;
int instance_size;
int in_object_properties;
if (function->shared()->is_generator()) {
instance_type = JS_GENERATOR_OBJECT_TYPE;
instance_size = JSGeneratorObject::kSize;
in_object_properties = 0;
} else {
instance_type = JS_OBJECT_TYPE;
instance_size = function->shared()->CalculateInstanceSize();
in_object_properties = function->shared()->CalculateInObjectProperties();
}
Handle<Map> map = isolate->factory()->NewMap(instance_type, instance_size);
// Fetch or allocate prototype.
Handle<Object> prototype;
if (function->has_instance_prototype()) {
prototype = handle(function->instance_prototype(), isolate);
} else {
prototype = isolate->factory()->NewFunctionPrototype(function);
}
map->set_inobject_properties(in_object_properties);
map->set_unused_property_fields(in_object_properties);
DCHECK(map->has_fast_object_elements());
// Finally link initial map and constructor function.
JSFunction::SetInitialMap(function, map, Handle<JSReceiver>::cast(prototype));
if (!function->shared()->is_generator()) {
function->StartInobjectSlackTracking();
}
}
void JSFunction::SetInstanceClassName(String* name) {
shared()->set_instance_class_name(name);
}
void JSFunction::PrintName(FILE* out) {
SmartArrayPointer<char> name = shared()->DebugName()->ToCString();
PrintF(out, "%s", name.get());
}
Context* JSFunction::NativeContextFromLiterals(FixedArray* literals) {
return Context::cast(literals->get(JSFunction::kLiteralNativeContextIndex));
}
// The filter is a pattern that matches function names in this way:
// "*" all; the default
// "-" all but the top-level function
// "-name" all but the function "name"
// "" only the top-level function
// "name" only the function "name"
// "name*" only functions starting with "name"
// "~" none; the tilde is not an identifier
bool JSFunction::PassesFilter(const char* raw_filter) {
if (*raw_filter == '*') return true;
String* name = shared()->DebugName();
Vector<const char> filter = CStrVector(raw_filter);
if (filter.length() == 0) return name->length() == 0;
if (filter[0] == '-') {
// Negative filter.
if (filter.length() == 1) {
return (name->length() != 0);
} else if (name->IsUtf8EqualTo(filter.SubVector(1, filter.length()))) {
return false;
}
if (filter[filter.length() - 1] == '*' &&
name->IsUtf8EqualTo(filter.SubVector(1, filter.length() - 1), true)) {
return false;
}
return true;
} else if (name->IsUtf8EqualTo(filter)) {
return true;
}
if (filter[filter.length() - 1] == '*' &&
name->IsUtf8EqualTo(filter.SubVector(0, filter.length() - 1), true)) {
return true;
}
return false;
}
void Oddball::Initialize(Isolate* isolate,
Handle<Oddball> oddball,
const char* to_string,
Handle<Object> to_number,
byte kind) {
Handle<String> internalized_to_string =
isolate->factory()->InternalizeUtf8String(to_string);
oddball->set_to_string(*internalized_to_string);
oddball->set_to_number(*to_number);
oddball->set_kind(kind);
}
void Script::InitLineEnds(Handle<Script> script) {
if (!script->line_ends()->IsUndefined()) return;
Isolate* isolate = script->GetIsolate();
if (!script->source()->IsString()) {
DCHECK(script->source()->IsUndefined());
Handle<FixedArray> empty = isolate->factory()->NewFixedArray(0);
script->set_line_ends(*empty);
DCHECK(script->line_ends()->IsFixedArray());
return;
}
Handle<String> src(String::cast(script->source()), isolate);
Handle<FixedArray> array = String::CalculateLineEnds(src, true);
if (*array != isolate->heap()->empty_fixed_array()) {
array->set_map(isolate->heap()->fixed_cow_array_map());
}
script->set_line_ends(*array);
DCHECK(script->line_ends()->IsFixedArray());
}
int Script::GetColumnNumber(Handle<Script> script, int code_pos) {
int line_number = GetLineNumber(script, code_pos);
if (line_number == -1) return -1;
DisallowHeapAllocation no_allocation;
FixedArray* line_ends_array = FixedArray::cast(script->line_ends());
line_number = line_number - script->line_offset()->value();
if (line_number == 0) return code_pos + script->column_offset()->value();
int prev_line_end_pos =
Smi::cast(line_ends_array->get(line_number - 1))->value();
return code_pos - (prev_line_end_pos + 1);
}
int Script::GetLineNumberWithArray(int code_pos) {
DisallowHeapAllocation no_allocation;
DCHECK(line_ends()->IsFixedArray());
FixedArray* line_ends_array = FixedArray::cast(line_ends());
int line_ends_len = line_ends_array->length();
if (line_ends_len == 0) return -1;
if ((Smi::cast(line_ends_array->get(0)))->value() >= code_pos) {
return line_offset()->value();
}
int left = 0;
int right = line_ends_len;
while (int half = (right - left) / 2) {
if ((Smi::cast(line_ends_array->get(left + half)))->value() > code_pos) {
right -= half;
} else {
left += half;
}
}
return right + line_offset()->value();
}
int Script::GetLineNumber(Handle<Script> script, int code_pos) {
InitLineEnds(script);
return script->GetLineNumberWithArray(code_pos);
}
int Script::GetLineNumber(int code_pos) {
DisallowHeapAllocation no_allocation;
if (!line_ends()->IsUndefined()) return GetLineNumberWithArray(code_pos);
// Slow mode: we do not have line_ends. We have to iterate through source.
if (!source()->IsString()) return -1;
String* source_string = String::cast(source());
int line = 0;
int len = source_string->length();
for (int pos = 0; pos < len; pos++) {
if (pos == code_pos) break;
if (source_string->Get(pos) == '\n') line++;
}
return line;
}
Handle<Object> Script::GetNameOrSourceURL(Handle<Script> script) {
Isolate* isolate = script->GetIsolate();
Handle<String> name_or_source_url_key =
isolate->factory()->InternalizeOneByteString(
STATIC_CHAR_VECTOR("nameOrSourceURL"));
Handle<JSObject> script_wrapper = Script::GetWrapper(script);
Handle<Object> property = Object::GetProperty(
script_wrapper, name_or_source_url_key).ToHandleChecked();
DCHECK(property->IsJSFunction());
Handle<JSFunction> method = Handle<JSFunction>::cast(property);
Handle<Object> result;
// Do not check against pending exception, since this function may be called
// when an exception has already been pending.
if (!Execution::TryCall(method, script_wrapper, 0, NULL).ToHandle(&result)) {
return isolate->factory()->undefined_value();
}
return result;
}
// Wrappers for scripts are kept alive and cached in weak global
// handles referred from foreign objects held by the scripts as long as
// they are used. When they are not used anymore, the garbage
// collector will call the weak callback on the global handle
// associated with the wrapper and get rid of both the wrapper and the
// handle.
static void ClearWrapperCacheWeakCallback(
const v8::WeakCallbackData<v8::Value, void>& data) {
Object** location = reinterpret_cast<Object**>(data.GetParameter());
JSValue* wrapper = JSValue::cast(*location);
Script::cast(wrapper->value())->ClearWrapperCache();
}
void Script::ClearWrapperCache() {
Foreign* foreign = wrapper();
Object** location = reinterpret_cast<Object**>(foreign->foreign_address());
DCHECK_EQ(foreign->foreign_address(), reinterpret_cast<Address>(location));
foreign->set_foreign_address(0);
GlobalHandles::Destroy(location);
GetIsolate()->counters()->script_wrappers()->Decrement();
}
Handle<JSObject> Script::GetWrapper(Handle<Script> script) {
if (script->wrapper()->foreign_address() != NULL) {
// Return a handle for the existing script wrapper from the cache.
return Handle<JSValue>(
*reinterpret_cast<JSValue**>(script->wrapper()->foreign_address()));
}
Isolate* isolate = script->GetIsolate();
// Construct a new script wrapper.
isolate->counters()->script_wrappers()->Increment();
Handle<JSFunction> constructor = isolate->script_function();
Handle<JSValue> result =
Handle<JSValue>::cast(isolate->factory()->NewJSObject(constructor));
result->set_value(*script);
// Create a new weak global handle and use it to cache the wrapper
// for future use. The cache will automatically be cleared by the
// garbage collector when it is not used anymore.
Handle<Object> handle = isolate->global_handles()->Create(*result);
GlobalHandles::MakeWeak(handle.location(),
reinterpret_cast<void*>(handle.location()),
&ClearWrapperCacheWeakCallback);
script->wrapper()->set_foreign_address(
reinterpret_cast<Address>(handle.location()));
return result;
}
String* SharedFunctionInfo::DebugName() {
Object* n = name();
if (!n->IsString() || String::cast(n)->length() == 0) return inferred_name();
return String::cast(n);
}
bool SharedFunctionInfo::HasSourceCode() const {
return !script()->IsUndefined() &&
!reinterpret_cast<Script*>(script())->source()->IsUndefined();
}
Handle<Object> SharedFunctionInfo::GetSourceCode() {
if (!HasSourceCode()) return GetIsolate()->factory()->undefined_value();
Handle<String> source(String::cast(Script::cast(script())->source()));
return GetIsolate()->factory()->NewSubString(
source, start_position(), end_position());
}
bool SharedFunctionInfo::IsInlineable() {
// Check that the function has a script associated with it.
if (!script()->IsScript()) return false;
if (optimization_disabled()) return false;
// If we never ran this (unlikely) then lets try to optimize it.
if (code()->kind() != Code::FUNCTION) return true;
return code()->optimizable();
}
int SharedFunctionInfo::SourceSize() {
return end_position() - start_position();
}
int SharedFunctionInfo::CalculateInstanceSize() {
int instance_size =
JSObject::kHeaderSize +
expected_nof_properties() * kPointerSize;
if (instance_size > JSObject::kMaxInstanceSize) {
instance_size = JSObject::kMaxInstanceSize;
}
return instance_size;
}
int SharedFunctionInfo::CalculateInObjectProperties() {
return (CalculateInstanceSize() - JSObject::kHeaderSize) / kPointerSize;
}
// Output the source code without any allocation in the heap.
OStream& operator<<(OStream& os, const SourceCodeOf& v) {
const SharedFunctionInfo* s = v.value;
// For some native functions there is no source.
if (!s->HasSourceCode()) return os << "<No Source>";
// Get the source for the script which this function came from.
// Don't use String::cast because we don't want more assertion errors while
// we are already creating a stack dump.
String* script_source =
reinterpret_cast<String*>(Script::cast(s->script())->source());
if (!script_source->LooksValid()) return os << "<Invalid Source>";
if (!s->is_toplevel()) {
os << "function ";
Object* name = s->name();
if (name->IsString() && String::cast(name)->length() > 0) {
String::cast(name)->PrintUC16(os);
}
}
int len = s->end_position() - s->start_position();
if (len <= v.max_length || v.max_length < 0) {
script_source->PrintUC16(os, s->start_position(), s->end_position());
return os;
} else {
script_source->PrintUC16(os, s->start_position(),
s->start_position() + v.max_length);
return os << "...\n";
}
}
static bool IsCodeEquivalent(Code* code, Code* recompiled) {
if (code->instruction_size() != recompiled->instruction_size()) return false;
ByteArray* code_relocation = code->relocation_info();
ByteArray* recompiled_relocation = recompiled->relocation_info();
int length = code_relocation->length();
if (length != recompiled_relocation->length()) return false;
int compare = memcmp(code_relocation->GetDataStartAddress(),
recompiled_relocation->GetDataStartAddress(),
length);
return compare == 0;
}
void SharedFunctionInfo::EnableDeoptimizationSupport(Code* recompiled) {
DCHECK(!has_deoptimization_support());
DisallowHeapAllocation no_allocation;
Code* code = this->code();
if (IsCodeEquivalent(code, recompiled)) {
// Copy the deoptimization data from the recompiled code.
code->set_deoptimization_data(recompiled->deoptimization_data());
code->set_has_deoptimization_support(true);
} else {
// TODO(3025757): In case the recompiled isn't equivalent to the
// old code, we have to replace it. We should try to avoid this
// altogether because it flushes valuable type feedback by
// effectively resetting all IC state.
ReplaceCode(recompiled);
}
DCHECK(has_deoptimization_support());
}
void SharedFunctionInfo::DisableOptimization(BailoutReason reason) {
// Disable optimization for the shared function info and mark the
// code as non-optimizable. The marker on the shared function info
// is there because we flush non-optimized code thereby loosing the
// non-optimizable information for the code. When the code is
// regenerated and set on the shared function info it is marked as
// non-optimizable if optimization is disabled for the shared
// function info.
set_optimization_disabled(true);
set_bailout_reason(reason);
// Code should be the lazy compilation stub or else unoptimized. If the
// latter, disable optimization for the code too.
DCHECK(code()->kind() == Code::FUNCTION || code()->kind() == Code::BUILTIN);
if (code()->kind() == Code::FUNCTION) {
code()->set_optimizable(false);
}
PROFILE(GetIsolate(), CodeDisableOptEvent(code(), this));
if (FLAG_trace_opt) {
PrintF("[disabled optimization for ");
ShortPrint();
PrintF(", reason: %s]\n", GetBailoutReason(reason));
}
}
bool SharedFunctionInfo::VerifyBailoutId(BailoutId id) {
DCHECK(!id.IsNone());
Code* unoptimized = code();
DeoptimizationOutputData* data =
DeoptimizationOutputData::cast(unoptimized->deoptimization_data());
unsigned ignore = Deoptimizer::GetOutputInfo(data, id, this);
USE(ignore);
return true; // Return true if there was no DCHECK.
}
void JSFunction::StartInobjectSlackTracking() {
DCHECK(has_initial_map() && !IsInobjectSlackTrackingInProgress());
if (!FLAG_clever_optimizations) return;
Map* map = initial_map();
// Only initiate the tracking the first time.
if (map->done_inobject_slack_tracking()) return;
map->set_done_inobject_slack_tracking(true);
// No tracking during the snapshot construction phase.
Isolate* isolate = GetIsolate();
if (isolate->serializer_enabled()) return;
if (map->unused_property_fields() == 0) return;
map->set_construction_count(kGenerousAllocationCount);
}
void SharedFunctionInfo::ResetForNewContext(int new_ic_age) {
code()->ClearInlineCaches();
// If we clear ICs, we need to clear the type feedback vector too, since
// CallICs are synced with a feedback vector slot.
ClearTypeFeedbackInfo();
set_ic_age(new_ic_age);
if (code()->kind() == Code::FUNCTION) {
code()->set_profiler_ticks(0);
if (optimization_disabled() &&
opt_count() >= FLAG_max_opt_count) {
// Re-enable optimizations if they were disabled due to opt_count limit.
set_optimization_disabled(false);
code()->set_optimizable(true);
}
set_opt_count(0);
set_deopt_count(0);
}
}
static void GetMinInobjectSlack(Map* map, void* data) {
int slack = map->unused_property_fields();
if (*reinterpret_cast<int*>(data) > slack) {
*reinterpret_cast<int*>(data) = slack;
}
}
static void ShrinkInstanceSize(Map* map, void* data) {
int slack = *reinterpret_cast<int*>(data);
map->set_inobject_properties(map->inobject_properties() - slack);
map->set_unused_property_fields(map->unused_property_fields() - slack);
map->set_instance_size(map->instance_size() - slack * kPointerSize);
// Visitor id might depend on the instance size, recalculate it.
map->set_visitor_id(StaticVisitorBase::GetVisitorId(map));
}
void JSFunction::CompleteInobjectSlackTracking() {
DCHECK(has_initial_map());
Map* map = initial_map();
DCHECK(map->done_inobject_slack_tracking());
map->set_construction_count(kNoSlackTracking);
int slack = map->unused_property_fields();
map->TraverseTransitionTree(&GetMinInobjectSlack, &slack);
if (slack != 0) {
// Resize the initial map and all maps in its transition tree.
map->TraverseTransitionTree(&ShrinkInstanceSize, &slack);
}
}
int SharedFunctionInfo::SearchOptimizedCodeMap(Context* native_context,
BailoutId osr_ast_id) {
DisallowHeapAllocation no_gc;
DCHECK(native_context->IsNativeContext());
if (!FLAG_cache_optimized_code) return -1;
Object* value = optimized_code_map();
if (!value->IsSmi()) {
FixedArray* optimized_code_map = FixedArray::cast(value);
int length = optimized_code_map->length();
Smi* osr_ast_id_smi = Smi::FromInt(osr_ast_id.ToInt());
for (int i = kEntriesStart; i < length; i += kEntryLength) {
if (optimized_code_map->get(i + kContextOffset) == native_context &&
optimized_code_map->get(i + kOsrAstIdOffset) == osr_ast_id_smi) {
return i + kCachedCodeOffset;
}
}
if (FLAG_trace_opt) {
PrintF("[didn't find optimized code in optimized code map for ");
ShortPrint();
PrintF("]\n");
}
}
return -1;
}
#define DECLARE_TAG(ignore1, name, ignore2) name,
const char* const VisitorSynchronization::kTags[
VisitorSynchronization::kNumberOfSyncTags] = {
VISITOR_SYNCHRONIZATION_TAGS_LIST(DECLARE_TAG)
};
#undef DECLARE_TAG
#define DECLARE_TAG(ignore1, ignore2, name) name,
const char* const VisitorSynchronization::kTagNames[
VisitorSynchronization::kNumberOfSyncTags] = {
VISITOR_SYNCHRONIZATION_TAGS_LIST(DECLARE_TAG)
};
#undef DECLARE_TAG
void ObjectVisitor::VisitCodeTarget(RelocInfo* rinfo) {
DCHECK(RelocInfo::IsCodeTarget(rinfo->rmode()));
Object* target = Code::GetCodeFromTargetAddress(rinfo->target_address());
Object* old_target = target;
VisitPointer(&target);
CHECK_EQ(target, old_target); // VisitPointer doesn't change Code* *target.
}
void ObjectVisitor::VisitCodeAgeSequence(RelocInfo* rinfo) {
DCHECK(RelocInfo::IsCodeAgeSequence(rinfo->rmode()));
Object* stub = rinfo->code_age_stub();
if (stub) {
VisitPointer(&stub);
}
}
void ObjectVisitor::VisitCodeEntry(Address entry_address) {
Object* code = Code::GetObjectFromEntryAddress(entry_address);
Object* old_code = code;
VisitPointer(&code);
if (code != old_code) {
Memory::Address_at(entry_address) = reinterpret_cast<Code*>(code)->entry();
}
}
void ObjectVisitor::VisitCell(RelocInfo* rinfo) {
DCHECK(rinfo->rmode() == RelocInfo::CELL);
Object* cell = rinfo->target_cell();
Object* old_cell = cell;
VisitPointer(&cell);
if (cell != old_cell) {
rinfo->set_target_cell(reinterpret_cast<Cell*>(cell));
}
}
void ObjectVisitor::VisitDebugTarget(RelocInfo* rinfo) {
DCHECK((RelocInfo::IsJSReturn(rinfo->rmode()) &&
rinfo->IsPatchedReturnSequence()) ||
(RelocInfo::IsDebugBreakSlot(rinfo->rmode()) &&
rinfo->IsPatchedDebugBreakSlotSequence()));
Object* target = Code::GetCodeFromTargetAddress(rinfo->call_address());
Object* old_target = target;
VisitPointer(&target);
CHECK_EQ(target, old_target); // VisitPointer doesn't change Code* *target.
}
void ObjectVisitor::VisitEmbeddedPointer(RelocInfo* rinfo) {
DCHECK(rinfo->rmode() == RelocInfo::EMBEDDED_OBJECT);
Object* p = rinfo->target_object();
VisitPointer(&p);
}
void ObjectVisitor::VisitExternalReference(RelocInfo* rinfo) {
Address p = rinfo->target_reference();
VisitExternalReference(&p);
}
void Code::InvalidateRelocation() {
InvalidateEmbeddedObjects();
set_relocation_info(GetHeap()->empty_byte_array());
}
void Code::InvalidateEmbeddedObjects() {
Object* undefined = GetHeap()->undefined_value();
Cell* undefined_cell = GetHeap()->undefined_cell();
int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::CELL);
for (RelocIterator it(this, mode_mask); !it.done(); it.next()) {
RelocInfo::Mode mode = it.rinfo()->rmode();
if (mode == RelocInfo::EMBEDDED_OBJECT) {
it.rinfo()->set_target_object(undefined, SKIP_WRITE_BARRIER);
} else if (mode == RelocInfo::CELL) {
it.rinfo()->set_target_cell(undefined_cell, SKIP_WRITE_BARRIER);
}
}
}
void Code::Relocate(intptr_t delta) {
for (RelocIterator it(this, RelocInfo::kApplyMask); !it.done(); it.next()) {
it.rinfo()->apply(delta, SKIP_ICACHE_FLUSH);
}
CpuFeatures::FlushICache(instruction_start(), instruction_size());
}
void Code::CopyFrom(const CodeDesc& desc) {
DCHECK(Marking::Color(this) == Marking::WHITE_OBJECT);
// copy code
CopyBytes(instruction_start(), desc.buffer,
static_cast<size_t>(desc.instr_size));
// copy reloc info
CopyBytes(relocation_start(),
desc.buffer + desc.buffer_size - desc.reloc_size,
static_cast<size_t>(desc.reloc_size));
// unbox handles and relocate
intptr_t delta = instruction_start() - desc.buffer;
int mode_mask = RelocInfo::kCodeTargetMask |
RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::CELL) |
RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY) |
RelocInfo::kApplyMask;
// Needed to find target_object and runtime_entry on X64
Assembler* origin = desc.origin;
AllowDeferredHandleDereference embedding_raw_address;
for (RelocIterator it(this, mode_mask); !it.done(); it.next()) {
RelocInfo::Mode mode = it.rinfo()->rmode();
if (mode == RelocInfo::EMBEDDED_OBJECT) {
Handle<Object> p = it.rinfo()->target_object_handle(origin);
it.rinfo()->set_target_object(*p, SKIP_WRITE_BARRIER, SKIP_ICACHE_FLUSH);
} else if (mode == RelocInfo::CELL) {
Handle<Cell> cell = it.rinfo()->target_cell_handle();
it.rinfo()->set_target_cell(*cell, SKIP_WRITE_BARRIER, SKIP_ICACHE_FLUSH);
} else if (RelocInfo::IsCodeTarget(mode)) {
// rewrite code handles in inline cache targets to direct
// pointers to the first instruction in the code object
Handle<Object> p = it.rinfo()->target_object_handle(origin);
Code* code = Code::cast(*p);
it.rinfo()->set_target_address(code->instruction_start(),
SKIP_WRITE_BARRIER,
SKIP_ICACHE_FLUSH);
} else if (RelocInfo::IsRuntimeEntry(mode)) {
Address p = it.rinfo()->target_runtime_entry(origin);
it.rinfo()->set_target_runtime_entry(p, SKIP_WRITE_BARRIER,
SKIP_ICACHE_FLUSH);
} else if (mode == RelocInfo::CODE_AGE_SEQUENCE) {
Handle<Object> p = it.rinfo()->code_age_stub_handle(origin);
Code* code = Code::cast(*p);
it.rinfo()->set_code_age_stub(code, SKIP_ICACHE_FLUSH);
} else {
it.rinfo()->apply(delta, SKIP_ICACHE_FLUSH);
}
}
CpuFeatures::FlushICache(instruction_start(), instruction_size());
}
// Locate the source position which is closest to the address in the code. This
// is using the source position information embedded in the relocation info.
// The position returned is relative to the beginning of the script where the
// source for this function is found.
int Code::SourcePosition(Address pc) {
int distance = kMaxInt;
int position = RelocInfo::kNoPosition; // Initially no position found.
// Run through all the relocation info to find the best matching source
// position. All the code needs to be considered as the sequence of the
// instructions in the code does not necessarily follow the same order as the
// source.
RelocIterator it(this, RelocInfo::kPositionMask);
while (!it.done()) {
// Only look at positions after the current pc.
if (it.rinfo()->pc() < pc) {
// Get position and distance.
int dist = static_cast<int>(pc - it.rinfo()->pc());
int pos = static_cast<int>(it.rinfo()->data());
// If this position is closer than the current candidate or if it has the
// same distance as the current candidate and the position is higher then
// this position is the new candidate.
if ((dist < distance) ||
(dist == distance && pos > position)) {
position = pos;
distance = dist;
}
}
it.next();
}
return position;
}
// Same as Code::SourcePosition above except it only looks for statement
// positions.
int Code::SourceStatementPosition(Address pc) {
// First find the position as close as possible using all position
// information.
int position = SourcePosition(pc);
// Now find the closest statement position before the position.
int statement_position = 0;
RelocIterator it(this, RelocInfo::kPositionMask);
while (!it.done()) {
if (RelocInfo::IsStatementPosition(it.rinfo()->rmode())) {
int p = static_cast<int>(it.rinfo()->data());
if (statement_position < p && p <= position) {
statement_position = p;
}
}
it.next();
}
return statement_position;
}
SafepointEntry Code::GetSafepointEntry(Address pc) {
SafepointTable table(this);
return table.FindEntry(pc);
}
Object* Code::FindNthObject(int n, Map* match_map) {
DCHECK(is_inline_cache_stub());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Object* object = info->target_object();
if (object->IsHeapObject()) {
if (HeapObject::cast(object)->map() == match_map) {
if (--n == 0) return object;
}
}
}
return NULL;
}
AllocationSite* Code::FindFirstAllocationSite() {
Object* result = FindNthObject(1, GetHeap()->allocation_site_map());
return (result != NULL) ? AllocationSite::cast(result) : NULL;
}
Map* Code::FindFirstMap() {
Object* result = FindNthObject(1, GetHeap()->meta_map());
return (result != NULL) ? Map::cast(result) : NULL;
}
void Code::FindAndReplace(const FindAndReplacePattern& pattern) {
DCHECK(is_inline_cache_stub() || is_handler());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
STATIC_ASSERT(FindAndReplacePattern::kMaxCount < 32);
int current_pattern = 0;
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Object* object = info->target_object();
if (object->IsHeapObject()) {
Map* map = HeapObject::cast(object)->map();
if (map == *pattern.find_[current_pattern]) {
info->set_target_object(*pattern.replace_[current_pattern]);
if (++current_pattern == pattern.count_) return;
}
}
}
UNREACHABLE();
}
void Code::FindAllMaps(MapHandleList* maps) {
DCHECK(is_inline_cache_stub());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Object* object = info->target_object();
if (object->IsMap()) maps->Add(handle(Map::cast(object)));
}
}
Code* Code::FindFirstHandler() {
DCHECK(is_inline_cache_stub());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Code* code = Code::GetCodeFromTargetAddress(info->target_address());
if (code->kind() == Code::HANDLER) return code;
}
return NULL;
}
bool Code::FindHandlers(CodeHandleList* code_list, int length) {
DCHECK(is_inline_cache_stub());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET);
int i = 0;
for (RelocIterator it(this, mask); !it.done(); it.next()) {
if (i == length) return true;
RelocInfo* info = it.rinfo();
Code* code = Code::GetCodeFromTargetAddress(info->target_address());
// IC stubs with handlers never contain non-handler code objects before
// handler targets.
if (code->kind() != Code::HANDLER) break;
code_list->Add(Handle<Code>(code));
i++;
}
return i == length;
}
MaybeHandle<Code> Code::FindHandlerForMap(Map* map) {
DCHECK(is_inline_cache_stub());
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
bool return_next = false;
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
if (info->rmode() == RelocInfo::EMBEDDED_OBJECT) {
Object* object = info->target_object();
if (object == map) return_next = true;
} else if (return_next) {
Code* code = Code::GetCodeFromTargetAddress(info->target_address());
DCHECK(code->kind() == Code::HANDLER);
return handle(code);
}
}
return MaybeHandle<Code>();
}
Name* Code::FindFirstName() {
DCHECK(is_inline_cache_stub());
DisallowHeapAllocation no_allocation;
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Object* object = info->target_object();
if (object->IsName()) return Name::cast(object);
}
return NULL;
}
void Code::ClearInlineCaches() {
ClearInlineCaches(NULL);
}
void Code::ClearInlineCaches(Code::Kind kind) {
ClearInlineCaches(&kind);
}
void Code::ClearInlineCaches(Code::Kind* kind) {
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
RelocInfo::ModeMask(RelocInfo::CONSTRUCT_CALL) |
RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
Code* target(Code::GetCodeFromTargetAddress(info->target_address()));
if (target->is_inline_cache_stub()) {
if (kind == NULL || *kind == target->kind()) {
IC::Clear(this->GetIsolate(), info->pc(),
info->host()->constant_pool());
}
}
}
}
void SharedFunctionInfo::ClearTypeFeedbackInfo() {
TypeFeedbackVector* vector = feedback_vector();
Heap* heap = GetHeap();
int length = vector->length();
for (int i = 0; i < length; i++) {
Object* obj = vector->get(i);
if (obj->IsHeapObject()) {
InstanceType instance_type =
HeapObject::cast(obj)->map()->instance_type();
switch (instance_type) {
case ALLOCATION_SITE_TYPE:
// AllocationSites are not cleared because they do not store
// information that leaks.
break;
// Fall through...
default:
vector->set(i, TypeFeedbackVector::RawUninitializedSentinel(heap),
SKIP_WRITE_BARRIER);
}
}
}
}
BailoutId Code::TranslatePcOffsetToAstId(uint32_t pc_offset) {
DisallowHeapAllocation no_gc;
DCHECK(kind() == FUNCTION);
BackEdgeTable back_edges(this, &no_gc);
for (uint32_t i = 0; i < back_edges.length(); i++) {
if (back_edges.pc_offset(i) == pc_offset) return back_edges.ast_id(i);
}
return BailoutId::None();
}
uint32_t Code::TranslateAstIdToPcOffset(BailoutId ast_id) {
DisallowHeapAllocation no_gc;
DCHECK(kind() == FUNCTION);
BackEdgeTable back_edges(this, &no_gc);
for (uint32_t i = 0; i < back_edges.length(); i++) {
if (back_edges.ast_id(i) == ast_id) return back_edges.pc_offset(i);
}
UNREACHABLE(); // We expect to find the back edge.
return 0;
}
void Code::MakeCodeAgeSequenceYoung(byte* sequence, Isolate* isolate) {
PatchPlatformCodeAge(isolate, sequence, kNoAgeCodeAge, NO_MARKING_PARITY);
}
void Code::MarkCodeAsExecuted(byte* sequence, Isolate* isolate) {
PatchPlatformCodeAge(isolate, sequence, kExecutedOnceCodeAge,
NO_MARKING_PARITY);
}
static Code::Age EffectiveAge(Code::Age age) {
if (age == Code::kNotExecutedCodeAge) {
// Treat that's never been executed as old immediately.
age = Code::kIsOldCodeAge;
} else if (age == Code::kExecutedOnceCodeAge) {
// Pre-age code that has only been executed once.
age = Code::kPreAgedCodeAge;
}
return age;
}
void Code::MakeOlder(MarkingParity current_parity) {
byte* sequence = FindCodeAgeSequence();
if (sequence != NULL) {
Age age;
MarkingParity code_parity;
Isolate* isolate = GetIsolate();
GetCodeAgeAndParity(isolate, sequence, &age, &code_parity);
age = EffectiveAge(age);
if (age != kLastCodeAge && code_parity != current_parity) {
PatchPlatformCodeAge(isolate,
sequence,
static_cast<Age>(age + 1),
current_parity);
}
}
}
bool Code::IsOld() {
return GetAge() >= kIsOldCodeAge;
}
byte* Code::FindCodeAgeSequence() {
return FLAG_age_code &&
prologue_offset() != Code::kPrologueOffsetNotSet &&
(kind() == OPTIMIZED_FUNCTION ||
(kind() == FUNCTION && !has_debug_break_slots()))
? instruction_start() + prologue_offset()
: NULL;
}
Code::Age Code::GetAge() {
return EffectiveAge(GetRawAge());
}
Code::Age Code::GetRawAge() {
byte* sequence = FindCodeAgeSequence();
if (sequence == NULL) {
return kNoAgeCodeAge;
}
Age age;
MarkingParity parity;
GetCodeAgeAndParity(GetIsolate(), sequence, &age, &parity);
return age;
}
void Code::GetCodeAgeAndParity(Code* code, Age* age,
MarkingParity* parity) {
Isolate* isolate = code->GetIsolate();
Builtins* builtins = isolate->builtins();
Code* stub = NULL;
#define HANDLE_CODE_AGE(AGE) \
stub = *builtins->Make##AGE##CodeYoungAgainEvenMarking(); \
if (code == stub) { \
*age = k##AGE##CodeAge; \
*parity = EVEN_MARKING_PARITY; \
return; \
} \
stub = *builtins->Make##AGE##CodeYoungAgainOddMarking(); \
if (code == stub) { \
*age = k##AGE##CodeAge; \
*parity = ODD_MARKING_PARITY; \
return; \
}
CODE_AGE_LIST(HANDLE_CODE_AGE)
#undef HANDLE_CODE_AGE
stub = *builtins->MarkCodeAsExecutedOnce();
if (code == stub) {
*age = kNotExecutedCodeAge;
*parity = NO_MARKING_PARITY;
return;
}
stub = *builtins->MarkCodeAsExecutedTwice();
if (code == stub) {
*age = kExecutedOnceCodeAge;
*parity = NO_MARKING_PARITY;
return;
}
UNREACHABLE();
}
Code* Code::GetCodeAgeStub(Isolate* isolate, Age age, MarkingParity parity) {
Builtins* builtins = isolate->builtins();
switch (age) {
#define HANDLE_CODE_AGE(AGE) \
case k##AGE##CodeAge: { \
Code* stub = parity == EVEN_MARKING_PARITY \
? *builtins->Make##AGE##CodeYoungAgainEvenMarking() \
: *builtins->Make##AGE##CodeYoungAgainOddMarking(); \
return stub; \
}
CODE_AGE_LIST(HANDLE_CODE_AGE)
#undef HANDLE_CODE_AGE
case kNotExecutedCodeAge: {
DCHECK(parity == NO_MARKING_PARITY);
return *builtins->MarkCodeAsExecutedOnce();
}
case kExecutedOnceCodeAge: {
DCHECK(parity == NO_MARKING_PARITY);
return *builtins->MarkCodeAsExecutedTwice();
}
default:
UNREACHABLE();
break;
}
return NULL;
}
void Code::PrintDeoptLocation(FILE* out, int bailout_id) {
const char* last_comment = NULL;
int mask = RelocInfo::ModeMask(RelocInfo::COMMENT)
| RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY);
for (RelocIterator it(this, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
if (info->rmode() == RelocInfo::COMMENT) {
last_comment = reinterpret_cast<const char*>(info->data());
} else if (last_comment != NULL) {
if ((bailout_id == Deoptimizer::GetDeoptimizationId(
GetIsolate(), info->target_address(), Deoptimizer::EAGER)) ||
(bailout_id == Deoptimizer::GetDeoptimizationId(
GetIsolate(), info->target_address(), Deoptimizer::SOFT)) ||
(bailout_id == Deoptimizer::GetDeoptimizationId(
GetIsolate(), info->target_address(), Deoptimizer::LAZY))) {
CHECK(RelocInfo::IsRuntimeEntry(info->rmode()));
PrintF(out, " %s\n", last_comment);
return;
}
}
}
}
bool Code::CanDeoptAt(Address pc) {
DeoptimizationInputData* deopt_data =
DeoptimizationInputData::cast(deoptimization_data());
Address code_start_address = instruction_start();
for (int i = 0; i < deopt_data->DeoptCount(); i++) {
if (deopt_data->Pc(i)->value() == -1) continue;
Address address = code_start_address + deopt_data->Pc(i)->value();
if (address == pc) return true;
}
return false;
}
// Identify kind of code.
const char* Code::Kind2String(Kind kind) {
switch (kind) {
#define CASE(name) case name: return #name;
CODE_KIND_LIST(CASE)
#undef CASE
case NUMBER_OF_KINDS: break;
}
UNREACHABLE();
return NULL;
}
#ifdef ENABLE_DISASSEMBLER
void DeoptimizationInputData::DeoptimizationInputDataPrint(
OStream& os) { // NOLINT
disasm::NameConverter converter;
int deopt_count = DeoptCount();
os << "Deoptimization Input Data (deopt points = " << deopt_count << ")\n";
if (0 != deopt_count) {
os << " index ast id argc pc";
if (FLAG_print_code_verbose) os << " commands";
os << "\n";
}
for (int i = 0; i < deopt_count; i++) {
// TODO(svenpanne) Add some basic formatting to our streams.
Vector<char> buf1 = Vector<char>::New(128);
SNPrintF(buf1, "%6d %6d %6d %6d", i, AstId(i).ToInt(),
ArgumentsStackHeight(i)->value(), Pc(i)->value());
os << buf1.start();
if (!FLAG_print_code_verbose) {
os << "\n";
continue;
}
// Print details of the frame translation.
int translation_index = TranslationIndex(i)->value();
TranslationIterator iterator(TranslationByteArray(), translation_index);
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator.Next());
DCHECK(Translation::BEGIN == opcode);
int frame_count = iterator.Next();
int jsframe_count = iterator.Next();
os << " " << Translation::StringFor(opcode)
<< " {frame count=" << frame_count
<< ", js frame count=" << jsframe_count << "}\n";
while (iterator.HasNext() &&
Translation::BEGIN !=
(opcode = static_cast<Translation::Opcode>(iterator.Next()))) {
Vector<char> buf2 = Vector<char>::New(128);
SNPrintF(buf2, "%27s %s ", "", Translation::StringFor(opcode));
os << buf2.start();
switch (opcode) {
case Translation::BEGIN:
UNREACHABLE();
break;
case Translation::JS_FRAME: {
int ast_id = iterator.Next();
int function_id = iterator.Next();
unsigned height = iterator.Next();
os << "{ast_id=" << ast_id << ", function=";
if (function_id != Translation::kSelfLiteralId) {
Object* function = LiteralArray()->get(function_id);
os << Brief(JSFunction::cast(function)->shared()->DebugName());
} else {
os << "<self>";
}
os << ", height=" << height << "}";
break;
}
case Translation::COMPILED_STUB_FRAME: {
Code::Kind stub_kind = static_cast<Code::Kind>(iterator.Next());
os << "{kind=" << stub_kind << "}";
break;
}
case Translation::ARGUMENTS_ADAPTOR_FRAME:
case Translation::CONSTRUCT_STUB_FRAME: {
int function_id = iterator.Next();
JSFunction* function =
JSFunction::cast(LiteralArray()->get(function_id));
unsigned height = iterator.Next();
os << "{function=" << Brief(function->shared()->DebugName())
<< ", height=" << height << "}";
break;
}
case Translation::GETTER_STUB_FRAME:
case Translation::SETTER_STUB_FRAME: {
int function_id = iterator.Next();
JSFunction* function =
JSFunction::cast(LiteralArray()->get(function_id));
os << "{function=" << Brief(function->shared()->DebugName()) << "}";
break;
}
case Translation::REGISTER: {
int reg_code = iterator.Next();
os << "{input=" << converter.NameOfCPURegister(reg_code) << "}";
break;
}
case Translation::INT32_REGISTER: {
int reg_code = iterator.Next();
os << "{input=" << converter.NameOfCPURegister(reg_code) << "}";
break;
}
case Translation::UINT32_REGISTER: {
int reg_code = iterator.Next();
os << "{input=" << converter.NameOfCPURegister(reg_code)
<< " (unsigned)}";
break;
}
case Translation::DOUBLE_REGISTER: {
int reg_code = iterator.Next();
os << "{input=" << DoubleRegister::AllocationIndexToString(reg_code)
<< "}";
break;
}
case Translation::STACK_SLOT: {
int input_slot_index = iterator.Next();
os << "{input=" << input_slot_index << "}";
break;
}
case Translation::INT32_STACK_SLOT: {
int input_slot_index = iterator.Next();
os << "{input=" << input_slot_index << "}";
break;
}
case Translation::UINT32_STACK_SLOT: {
int input_slot_index = iterator.Next();
os << "{input=" << input_slot_index << " (unsigned)}";
break;
}
case Translation::DOUBLE_STACK_SLOT: {
int input_slot_index = iterator.Next();
os << "{input=" << input_slot_index << "}";
break;
}
case Translation::LITERAL: {
unsigned literal_index = iterator.Next();
os << "{literal_id=" << literal_index << "}";
break;
}
case Translation::DUPLICATED_OBJECT: {
int object_index = iterator.Next();
os << "{object_index=" << object_index << "}";
break;
}
case Translation::ARGUMENTS_OBJECT:
case Translation::CAPTURED_OBJECT: {
int args_length = iterator.Next();
os << "{length=" << args_length << "}";
break;
}
}
os << "\n";
}
}
}
void DeoptimizationOutputData::DeoptimizationOutputDataPrint(
OStream& os) { // NOLINT
os << "Deoptimization Output Data (deopt points = " << this->DeoptPoints()
<< ")\n";
if (this->DeoptPoints() == 0) return;
os << "ast id pc state\n";
for (int i = 0; i < this->DeoptPoints(); i++) {
int pc_and_state = this->PcAndState(i)->value();
// TODO(svenpanne) Add some basic formatting to our streams.
Vector<char> buf = Vector<char>::New(100);
SNPrintF(buf, "%6d %8d %s\n", this->AstId(i).ToInt(),
FullCodeGenerator::PcField::decode(pc_and_state),
FullCodeGenerator::State2String(
FullCodeGenerator::StateField::decode(pc_and_state)));
os << buf.start();
}
}
const char* Code::ICState2String(InlineCacheState state) {
switch (state) {
case UNINITIALIZED: return "UNINITIALIZED";
case PREMONOMORPHIC: return "PREMONOMORPHIC";
case MONOMORPHIC: return "MONOMORPHIC";
case PROTOTYPE_FAILURE:
return "PROTOTYPE_FAILURE";
case POLYMORPHIC: return "POLYMORPHIC";
case MEGAMORPHIC: return "MEGAMORPHIC";
case GENERIC: return "GENERIC";
case DEBUG_STUB: return "DEBUG_STUB";
case DEFAULT:
return "DEFAULT";
}
UNREACHABLE();
return NULL;
}
const char* Code::StubType2String(StubType type) {
switch (type) {
case NORMAL: return "NORMAL";
case FAST: return "FAST";
}
UNREACHABLE(); // keep the compiler happy
return NULL;
}
void Code::PrintExtraICState(OStream& os, // NOLINT
Kind kind, ExtraICState extra) {
os << "extra_ic_state = ";
if ((kind == STORE_IC || kind == KEYED_STORE_IC) && (extra == STRICT)) {
os << "STRICT\n";
} else {
os << extra << "\n";
}
}
void Code::Disassemble(const char* name, OStream& os) { // NOLINT
os << "kind = " << Kind2String(kind()) << "\n";
if (IsCodeStubOrIC()) {
const char* n = CodeStub::MajorName(CodeStub::GetMajorKey(this), true);
os << "major_key = " << (n == NULL ? "null" : n) << "\n";
}
if (is_inline_cache_stub()) {
os << "ic_state = " << ICState2String(ic_state()) << "\n";
PrintExtraICState(os, kind(), extra_ic_state());
if (ic_state() == MONOMORPHIC) {
os << "type = " << StubType2String(type()) << "\n";
}
if (is_compare_ic_stub()) {
DCHECK(CodeStub::GetMajorKey(this) == CodeStub::CompareIC);
CompareICStub stub(stub_key(), GetIsolate());
os << "compare_state = " << CompareICState::GetStateName(stub.left())
<< "*" << CompareICState::GetStateName(stub.right()) << " -> "
<< CompareICState::GetStateName(stub.state()) << "\n";
os << "compare_operation = " << Token::Name(stub.op()) << "\n";
}
}
if ((name != NULL) && (name[0] != '\0')) {
os << "name = " << name << "\n";
}
if (kind() == OPTIMIZED_FUNCTION) {
os << "stack_slots = " << stack_slots() << "\n";
}
os << "Instructions (size = " << instruction_size() << ")\n";
// TODO(svenpanne) The Disassembler should use streams, too!
{
CodeTracer::Scope trace_scope(GetIsolate()->GetCodeTracer());
Disassembler::Decode(trace_scope.file(), this);
}
os << "\n";
if (kind() == FUNCTION) {
DeoptimizationOutputData* data =
DeoptimizationOutputData::cast(this->deoptimization_data());
data->DeoptimizationOutputDataPrint(os);
} else if (kind() == OPTIMIZED_FUNCTION) {
DeoptimizationInputData* data =
DeoptimizationInputData::cast(this->deoptimization_data());
data->DeoptimizationInputDataPrint(os);
}
os << "\n";
if (is_crankshafted()) {
SafepointTable table(this);
os << "Safepoints (size = " << table.size() << ")\n";
for (unsigned i = 0; i < table.length(); i++) {
unsigned pc_offset = table.GetPcOffset(i);
os << (instruction_start() + pc_offset) << " ";
// TODO(svenpanne) Add some basic formatting to our streams.
Vector<char> buf1 = Vector<char>::New(30);
SNPrintF(buf1, "%4d", pc_offset);
os << buf1.start() << " ";
table.PrintEntry(i, os);
os << " (sp -> fp) ";
SafepointEntry entry = table.GetEntry(i);
if (entry.deoptimization_index() != Safepoint::kNoDeoptimizationIndex) {
Vector<char> buf2 = Vector<char>::New(30);
SNPrintF(buf2, "%6d", entry.deoptimization_index());
os << buf2.start();
} else {
os << "<none>";
}
if (entry.argument_count() > 0) {
os << " argc: " << entry.argument_count();
}
os << "\n";
}
os << "\n";
} else if (kind() == FUNCTION) {
unsigned offset = back_edge_table_offset();
// If there is no back edge table, the "table start" will be at or after
// (due to alignment) the end of the instruction stream.
if (static_cast<int>(offset) < instruction_size()) {
DisallowHeapAllocation no_gc;
BackEdgeTable back_edges(this, &no_gc);
os << "Back edges (size = " << back_edges.length() << ")\n";
os << "ast_id pc_offset loop_depth\n";
for (uint32_t i = 0; i < back_edges.length(); i++) {
Vector<char> buf = Vector<char>::New(100);
SNPrintF(buf, "%6d %9u %10u\n", back_edges.ast_id(i).ToInt(),
back_edges.pc_offset(i), back_edges.loop_depth(i));
os << buf.start();
}
os << "\n";
}
#ifdef OBJECT_PRINT
if (!type_feedback_info()->IsUndefined()) {
OFStream os(stdout);
TypeFeedbackInfo::cast(type_feedback_info())->TypeFeedbackInfoPrint(os);
os << "\n";
}
#endif
}
os << "RelocInfo (size = " << relocation_size() << ")\n";
for (RelocIterator it(this); !it.done(); it.next()) {
it.rinfo()->Print(GetIsolate(), os);
}
os << "\n";
}
#endif // ENABLE_DISASSEMBLER
Handle<FixedArray> JSObject::SetFastElementsCapacityAndLength(
Handle<JSObject> object,
int capacity,
int length,
SetFastElementsCapacitySmiMode smi_mode) {
// We should never end in here with a pixel or external array.
DCHECK(!object->HasExternalArrayElements());
// Allocate a new fast elements backing store.
Handle<FixedArray> new_elements =
object->GetIsolate()->factory()->NewUninitializedFixedArray(capacity);
ElementsKind elements_kind = object->GetElementsKind();
ElementsKind new_elements_kind;
// The resized array has FAST_*_SMI_ELEMENTS if the capacity mode forces it,
// or if it's allowed and the old elements array contained only SMIs.
bool has_fast_smi_elements =
(smi_mode == kForceSmiElements) ||
((smi_mode == kAllowSmiElements) && object->HasFastSmiElements());
if (has_fast_smi_elements) {
if (IsHoleyElementsKind(elements_kind)) {
new_elements_kind = FAST_HOLEY_SMI_ELEMENTS;
} else {
new_elements_kind = FAST_SMI_ELEMENTS;
}
} else {
if (IsHoleyElementsKind(elements_kind)) {
new_elements_kind = FAST_HOLEY_ELEMENTS;
} else {
new_elements_kind = FAST_ELEMENTS;
}
}
Handle<FixedArrayBase> old_elements(object->elements());
ElementsAccessor* accessor = ElementsAccessor::ForKind(new_elements_kind);
accessor->CopyElements(object, new_elements, elements_kind);
if (elements_kind != SLOPPY_ARGUMENTS_ELEMENTS) {
Handle<Map> new_map = (new_elements_kind != elements_kind)
? GetElementsTransitionMap(object, new_elements_kind)
: handle(object->map());
JSObject::ValidateElements(object);
JSObject::SetMapAndElements(object, new_map, new_elements);
// Transition through the allocation site as well if present.
JSObject::UpdateAllocationSite(object, new_elements_kind);
} else {
Handle<FixedArray> parameter_map = Handle<FixedArray>::cast(old_elements);
parameter_map->set(1, *new_elements);
}
if (FLAG_trace_elements_transitions) {
PrintElementsTransition(stdout, object, elements_kind, old_elements,
object->GetElementsKind(), new_elements);
}
if (object->IsJSArray()) {
Handle<JSArray>::cast(object)->set_length(Smi::FromInt(length));
}
return new_elements;
}
void JSObject::SetFastDoubleElementsCapacityAndLength(Handle<JSObject> object,
int capacity,
int length) {
// We should never end in here with a pixel or external array.
DCHECK(!object->HasExternalArrayElements());
Handle<FixedArrayBase> elems =
object->GetIsolate()->factory()->NewFixedDoubleArray(capacity);
ElementsKind elements_kind = object->GetElementsKind();
CHECK(elements_kind != SLOPPY_ARGUMENTS_ELEMENTS);
ElementsKind new_elements_kind = elements_kind;
if (IsHoleyElementsKind(elements_kind)) {
new_elements_kind = FAST_HOLEY_DOUBLE_ELEMENTS;
} else {
new_elements_kind = FAST_DOUBLE_ELEMENTS;
}
Handle<Map> new_map = GetElementsTransitionMap(object, new_elements_kind);
Handle<FixedArrayBase> old_elements(object->elements());
ElementsAccessor* accessor = ElementsAccessor::ForKind(FAST_DOUBLE_ELEMENTS);
accessor->CopyElements(object, elems, elements_kind);
JSObject::ValidateElements(object);
JSObject::SetMapAndElements(object, new_map, elems);
if (FLAG_trace_elements_transitions) {
PrintElementsTransition(stdout, object, elements_kind, old_elements,
object->GetElementsKind(), elems);
}
if (object->IsJSArray()) {
Handle<JSArray>::cast(object)->set_length(Smi::FromInt(length));
}
}
// static
void JSArray::Initialize(Handle<JSArray> array, int capacity, int length) {
DCHECK(capacity >= 0);
array->GetIsolate()->factory()->NewJSArrayStorage(
array, length, capacity, INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE);
}
void JSArray::Expand(Handle<JSArray> array, int required_size) {
ElementsAccessor* accessor = array->GetElementsAccessor();
accessor->SetCapacityAndLength(array, required_size, required_size);
}
// Returns false if the passed-in index is marked non-configurable,
// which will cause the ES5 truncation operation to halt, and thus
// no further old values need be collected.
static bool GetOldValue(Isolate* isolate,
Handle<JSObject> object,
uint32_t index,
List<Handle<Object> >* old_values,
List<uint32_t>* indices) {
Maybe<PropertyAttributes> maybe =
JSReceiver::GetOwnElementAttribute(object, index);
DCHECK(maybe.has_value);
DCHECK(maybe.value != ABSENT);
if (maybe.value == DONT_DELETE) return false;
Handle<Object> value;
if (!JSObject::GetOwnElementAccessorPair(object, index).is_null()) {
value = Handle<Object>::cast(isolate->factory()->the_hole_value());
} else {
value = Object::GetElement(isolate, object, index).ToHandleChecked();
}
old_values->Add(value);
indices->Add(index);
return true;
}
static void EnqueueSpliceRecord(Handle<JSArray> object,
uint32_t index,
Handle<JSArray> deleted,
uint32_t add_count) {
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
Handle<Object> index_object = isolate->factory()->NewNumberFromUint(index);
Handle<Object> add_count_object =
isolate->factory()->NewNumberFromUint(add_count);
Handle<Object> args[] =
{ object, index_object, deleted, add_count_object };
Execution::Call(isolate,
Handle<JSFunction>(isolate->observers_enqueue_splice()),
isolate->factory()->undefined_value(),
arraysize(args),
args).Assert();
}
static void BeginPerformSplice(Handle<JSArray> object) {
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
Handle<Object> args[] = { object };
Execution::Call(isolate,
Handle<JSFunction>(isolate->observers_begin_perform_splice()),
isolate->factory()->undefined_value(),
arraysize(args),
args).Assert();
}
static void EndPerformSplice(Handle<JSArray> object) {
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
Handle<Object> args[] = { object };
Execution::Call(isolate,
Handle<JSFunction>(isolate->observers_end_perform_splice()),
isolate->factory()->undefined_value(),
arraysize(args),
args).Assert();
}
MaybeHandle<Object> JSArray::SetElementsLength(
Handle<JSArray> array,
Handle<Object> new_length_handle) {
if (array->HasFastElements()) {
// If the new array won't fit in a some non-trivial fraction of the max old
// space size, then force it to go dictionary mode.
int max_fast_array_size = static_cast<int>(
(array->GetHeap()->MaxOldGenerationSize() / kDoubleSize) / 4);
if (new_length_handle->IsNumber() &&
NumberToInt32(*new_length_handle) >= max_fast_array_size) {
NormalizeElements(array);
}
}
// We should never end in here with a pixel or external array.
DCHECK(array->AllowsSetElementsLength());
if (!array->map()->is_observed()) {
return array->GetElementsAccessor()->SetLength(array, new_length_handle);
}
Isolate* isolate = array->GetIsolate();
List<uint32_t> indices;
List<Handle<Object> > old_values;
Handle<Object> old_length_handle(array->length(), isolate);
uint32_t old_length = 0;
CHECK(old_length_handle->ToArrayIndex(&old_length));
uint32_t new_length = 0;
CHECK(new_length_handle->ToArrayIndex(&new_length));
static const PropertyAttributes kNoAttrFilter = NONE;
int num_elements = array->NumberOfOwnElements(kNoAttrFilter);
if (num_elements > 0) {
if (old_length == static_cast<uint32_t>(num_elements)) {
// Simple case for arrays without holes.
for (uint32_t i = old_length - 1; i + 1 > new_length; --i) {
if (!GetOldValue(isolate, array, i, &old_values, &indices)) break;
}
} else {
// For sparse arrays, only iterate over existing elements.
// TODO(rafaelw): For fast, sparse arrays, we can avoid iterating over
// the to-be-removed indices twice.
Handle<FixedArray> keys = isolate->factory()->NewFixedArray(num_elements);
array->GetOwnElementKeys(*keys, kNoAttrFilter);
while (num_elements-- > 0) {
uint32_t index = NumberToUint32(keys->get(num_elements));
if (index < new_length) break;
if (!GetOldValue(isolate, array, index, &old_values, &indices)) break;
}
}
}
Handle<Object> hresult;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, hresult,
array->GetElementsAccessor()->SetLength(array, new_length_handle),
Object);
CHECK(array->length()->ToArrayIndex(&new_length));
if (old_length == new_length) return hresult;
BeginPerformSplice(array);
for (int i = 0; i < indices.length(); ++i) {
// For deletions where the property was an accessor, old_values[i]
// will be the hole, which instructs EnqueueChangeRecord to elide
// the "oldValue" property.
JSObject::EnqueueChangeRecord(
array, "delete", isolate->factory()->Uint32ToString(indices[i]),
old_values[i]);
}
JSObject::EnqueueChangeRecord(
array, "update", isolate->factory()->length_string(),
old_length_handle);
EndPerformSplice(array);
uint32_t index = Min(old_length, new_length);
uint32_t add_count = new_length > old_length ? new_length - old_length : 0;
uint32_t delete_count = new_length < old_length ? old_length - new_length : 0;
Handle<JSArray> deleted = isolate->factory()->NewJSArray(0);
if (delete_count > 0) {
for (int i = indices.length() - 1; i >= 0; i--) {
// Skip deletions where the property was an accessor, leaving holes
// in the array of old values.
if (old_values[i]->IsTheHole()) continue;
JSObject::SetElement(
deleted, indices[i] - index, old_values[i], NONE, SLOPPY).Assert();
}
SetProperty(deleted, isolate->factory()->length_string(),
isolate->factory()->NewNumberFromUint(delete_count),
STRICT).Assert();
}
EnqueueSpliceRecord(array, index, deleted, add_count);
return hresult;
}
Handle<Map> Map::GetPrototypeTransition(Handle<Map> map,
Handle<Object> prototype) {
FixedArray* cache = map->GetPrototypeTransitions();
int number_of_transitions = map->NumberOfProtoTransitions();
const int proto_offset =
kProtoTransitionHeaderSize + kProtoTransitionPrototypeOffset;
const int map_offset = kProtoTransitionHeaderSize + kProtoTransitionMapOffset;
const int step = kProtoTransitionElementsPerEntry;
for (int i = 0; i < number_of_transitions; i++) {
if (cache->get(proto_offset + i * step) == *prototype) {
Object* result = cache->get(map_offset + i * step);
return Handle<Map>(Map::cast(result));
}
}
return Handle<Map>();
}
Handle<Map> Map::PutPrototypeTransition(Handle<Map> map,
Handle<Object> prototype,
Handle<Map> target_map) {
DCHECK(target_map->IsMap());
DCHECK(HeapObject::cast(*prototype)->map()->IsMap());
// Don't cache prototype transition if this map is either shared, or a map of
// a prototype.
if (map->is_prototype_map()) return map;
if (map->is_dictionary_map() || !FLAG_cache_prototype_transitions) return map;
const int step = kProtoTransitionElementsPerEntry;
const int header = kProtoTransitionHeaderSize;
Handle<FixedArray> cache(map->GetPrototypeTransitions());
int capacity = (cache->length() - header) / step;
int transitions = map->NumberOfProtoTransitions() + 1;
if (transitions > capacity) {
if (capacity > kMaxCachedPrototypeTransitions) return map;
// Grow array by factor 2 over and above what we need.
cache = FixedArray::CopySize(cache, transitions * 2 * step + header);
SetPrototypeTransitions(map, cache);
}
// Reload number of transitions as GC might shrink them.
int last = map->NumberOfProtoTransitions();
int entry = header + last * step;
cache->set(entry + kProtoTransitionPrototypeOffset, *prototype);
cache->set(entry + kProtoTransitionMapOffset, *target_map);
map->SetNumberOfProtoTransitions(last + 1);
return map;
}
void Map::ZapTransitions() {
TransitionArray* transition_array = transitions();
// TODO(mstarzinger): Temporarily use a slower version instead of the faster
// MemsetPointer to investigate a crasher. Switch back to MemsetPointer.
Object** data = transition_array->data_start();
Object* the_hole = GetHeap()->the_hole_value();
int length = transition_array->length();
for (int i = 0; i < length; i++) {
data[i] = the_hole;
}
}
void Map::ZapPrototypeTransitions() {
FixedArray* proto_transitions = GetPrototypeTransitions();
MemsetPointer(proto_transitions->data_start(),
GetHeap()->the_hole_value(),
proto_transitions->length());
}
// static
void Map::AddDependentCompilationInfo(Handle<Map> map,
DependentCode::DependencyGroup group,
CompilationInfo* info) {
Handle<DependentCode> codes =
DependentCode::Insert(handle(map->dependent_code(), info->isolate()),
group, info->object_wrapper());
if (*codes != map->dependent_code()) map->set_dependent_code(*codes);
info->dependencies(group)->Add(map, info->zone());
}
// static
void Map::AddDependentCode(Handle<Map> map,
DependentCode::DependencyGroup group,
Handle<Code> code) {
Handle<DependentCode> codes = DependentCode::Insert(
Handle<DependentCode>(map->dependent_code()), group, code);
if (*codes != map->dependent_code()) map->set_dependent_code(*codes);
}
// static
void Map::AddDependentIC(Handle<Map> map,
Handle<Code> stub) {
DCHECK(stub->next_code_link()->IsUndefined());
int n = map->dependent_code()->number_of_entries(DependentCode::kWeakICGroup);
if (n == 0) {
// Slow path: insert the head of the list with possible heap allocation.
Map::AddDependentCode(map, DependentCode::kWeakICGroup, stub);
} else {
// Fast path: link the stub to the existing head of the list without any
// heap allocation.
DCHECK(n == 1);
map->dependent_code()->AddToDependentICList(stub);
}
}
DependentCode::GroupStartIndexes::GroupStartIndexes(DependentCode* entries) {
Recompute(entries);
}
void DependentCode::GroupStartIndexes::Recompute(DependentCode* entries) {
start_indexes_[0] = 0;
for (int g = 1; g <= kGroupCount; g++) {
int count = entries->number_of_entries(static_cast<DependencyGroup>(g - 1));
start_indexes_[g] = start_indexes_[g - 1] + count;
}
}
DependentCode* DependentCode::ForObject(Handle<HeapObject> object,
DependencyGroup group) {
AllowDeferredHandleDereference dependencies_are_safe;
if (group == DependentCode::kPropertyCellChangedGroup) {
return Handle<PropertyCell>::cast(object)->dependent_code();
} else if (group == DependentCode::kAllocationSiteTenuringChangedGroup ||
group == DependentCode::kAllocationSiteTransitionChangedGroup) {
return Handle<AllocationSite>::cast(object)->dependent_code();
}
return Handle<Map>::cast(object)->dependent_code();
}
Handle<DependentCode> DependentCode::Insert(Handle<DependentCode> entries,
DependencyGroup group,
Handle<Object> object) {
GroupStartIndexes starts(*entries);
int start = starts.at(group);
int end = starts.at(group + 1);
int number_of_entries = starts.number_of_entries();
// Check for existing entry to avoid duplicates.
for (int i = start; i < end; i++) {
if (entries->object_at(i) == *object) return entries;
}
if (entries->length() < kCodesStartIndex + number_of_entries + 1) {
int capacity = kCodesStartIndex + number_of_entries + 1;
if (capacity > 5) capacity = capacity * 5 / 4;
Handle<DependentCode> new_entries = Handle<DependentCode>::cast(
FixedArray::CopySize(entries, capacity, TENURED));
// The number of codes can change after GC.
starts.Recompute(*entries);
start = starts.at(group);
end = starts.at(group + 1);
number_of_entries = starts.number_of_entries();
for (int i = 0; i < number_of_entries; i++) {
entries->clear_at(i);
}
// If the old fixed array was empty, we need to reset counters of the
// new array.
if (number_of_entries == 0) {
for (int g = 0; g < kGroupCount; g++) {
new_entries->set_number_of_entries(static_cast<DependencyGroup>(g), 0);
}
}
entries = new_entries;
}
entries->ExtendGroup(group);
entries->set_object_at(end, *object);
entries->set_number_of_entries(group, end + 1 - start);
return entries;
}
void DependentCode::UpdateToFinishedCode(DependencyGroup group,
CompilationInfo* info,
Code* code) {
DisallowHeapAllocation no_gc;
AllowDeferredHandleDereference get_object_wrapper;
Foreign* info_wrapper = *info->object_wrapper();
GroupStartIndexes starts(this);
int start = starts.at(group);
int end = starts.at(group + 1);
for (int i = start; i < end; i++) {
if (object_at(i) == info_wrapper) {
set_object_at(i, code);
break;
}
}
#ifdef DEBUG
for (int i = start; i < end; i++) {
DCHECK(is_code_at(i) || compilation_info_at(i) != info);
}
#endif
}
void DependentCode::RemoveCompilationInfo(DependentCode::DependencyGroup group,
CompilationInfo* info) {
DisallowHeapAllocation no_allocation;
AllowDeferredHandleDereference get_object_wrapper;
Foreign* info_wrapper = *info->object_wrapper();
GroupStartIndexes starts(this);
int start = starts.at(group);
int end = starts.at(group + 1);
// Find compilation info wrapper.
int info_pos = -1;
for (int i = start; i < end; i++) {
if (object_at(i) == info_wrapper) {
info_pos = i;
break;
}
}
if (info_pos == -1) return; // Not found.
int gap = info_pos;
// Use the last of each group to fill the gap in the previous group.
for (int i = group; i < kGroupCount; i++) {
int last_of_group = starts.at(i + 1) - 1;
DCHECK(last_of_group >= gap);
if (last_of_group == gap) continue;
copy(last_of_group, gap);
gap = last_of_group;
}
DCHECK(gap == starts.number_of_entries() - 1);
clear_at(gap); // Clear last gap.
set_number_of_entries(group, end - start - 1);
#ifdef DEBUG
for (int i = start; i < end - 1; i++) {
DCHECK(is_code_at(i) || compilation_info_at(i) != info);
}
#endif
}
static bool CodeListContains(Object* head, Code* code) {
while (!head->IsUndefined()) {
if (head == code) return true;
head = Code::cast(head)->next_code_link();
}
return false;
}
bool DependentCode::Contains(DependencyGroup group, Code* code) {
GroupStartIndexes starts(this);
int start = starts.at(group);
int end = starts.at(group + 1);
if (group == kWeakICGroup) {
return CodeListContains(object_at(start), code);
}
for (int i = start; i < end; i++) {
if (object_at(i) == code) return true;
}
return false;
}
bool DependentCode::MarkCodeForDeoptimization(
Isolate* isolate,
DependentCode::DependencyGroup group) {
DisallowHeapAllocation no_allocation_scope;
DependentCode::GroupStartIndexes starts(this);
int start = starts.at(group);
int end = starts.at(group + 1);
int code_entries = starts.number_of_entries();
if (start == end) return false;
// Mark all the code that needs to be deoptimized.
bool marked = false;
for (int i = start; i < end; i++) {
if (is_code_at(i)) {
Code* code = code_at(i);
if (!code->marked_for_deoptimization()) {
SetMarkedForDeoptimization(code, group);
marked = true;
}
} else {
CompilationInfo* info = compilation_info_at(i);
info->AbortDueToDependencyChange();
}
}
// Compact the array by moving all subsequent groups to fill in the new holes.
for (int src = end, dst = start; src < code_entries; src++, dst++) {
copy(src, dst);
}
// Now the holes are at the end of the array, zap them for heap-verifier.
int removed = end - start;
for (int i = code_entries - removed; i < code_entries; i++) {
clear_at(i);
}
set_number_of_entries(group, 0);
return marked;
}
void DependentCode::DeoptimizeDependentCodeGroup(
Isolate* isolate,
DependentCode::DependencyGroup group) {
DCHECK(AllowCodeDependencyChange::IsAllowed());
DisallowHeapAllocation no_allocation_scope;
bool marked = MarkCodeForDeoptimization(isolate, group);
if (marked) Deoptimizer::DeoptimizeMarkedCode(isolate);
}
void DependentCode::AddToDependentICList(Handle<Code> stub) {
DisallowHeapAllocation no_heap_allocation;
GroupStartIndexes starts(this);
int i = starts.at(kWeakICGroup);
Object* head = object_at(i);
// Try to insert the stub after the head of the list to minimize number of
// writes to the DependentCode array, since a write to the array can make it
// strong if it was alread marked by incremental marker.
if (head->IsCode()) {
stub->set_next_code_link(Code::cast(head)->next_code_link());
Code::cast(head)->set_next_code_link(*stub);
} else {
stub->set_next_code_link(head);
set_object_at(i, *stub);
}
}
void DependentCode::SetMarkedForDeoptimization(Code* code,
DependencyGroup group) {
code->set_marked_for_deoptimization(true);
if (FLAG_trace_deopt &&
(code->deoptimization_data() != code->GetHeap()->empty_fixed_array())) {
DeoptimizationInputData* deopt_data =
DeoptimizationInputData::cast(code->deoptimization_data());
CodeTracer::Scope scope(code->GetHeap()->isolate()->GetCodeTracer());
PrintF(scope.file(), "[marking dependent code 0x%08" V8PRIxPTR
" (opt #%d) for deoptimization, reason: %s]\n",
reinterpret_cast<intptr_t>(code),
deopt_data->OptimizationId()->value(), DependencyGroupName(group));
}
}
const char* DependentCode::DependencyGroupName(DependencyGroup group) {
switch (group) {
case kWeakICGroup:
return "weak-ic";
case kWeakCodeGroup:
return "weak-code";
case kTransitionGroup:
return "transition";
case kPrototypeCheckGroup:
return "prototype-check";
case kElementsCantBeAddedGroup:
return "elements-cant-be-added";
case kPropertyCellChangedGroup:
return "property-cell-changed";
case kFieldTypeGroup:
return "field-type";
case kInitialMapChangedGroup:
return "initial-map-changed";
case kAllocationSiteTenuringChangedGroup:
return "allocation-site-tenuring-changed";
case kAllocationSiteTransitionChangedGroup:
return "allocation-site-transition-changed";
}
UNREACHABLE();
return "?";
}
Handle<Map> Map::TransitionToPrototype(Handle<Map> map,
Handle<Object> prototype) {
Handle<Map> new_map = GetPrototypeTransition(map, prototype);
if (new_map.is_null()) {
new_map = Copy(map);
PutPrototypeTransition(map, prototype, new_map);
new_map->set_prototype(*prototype);
}
return new_map;
}
MaybeHandle<Object> JSObject::SetPrototype(Handle<JSObject> object,
Handle<Object> value,
bool from_javascript) {
#ifdef DEBUG
int size = object->Size();
#endif
Isolate* isolate = object->GetIsolate();
Heap* heap = isolate->heap();
// Silently ignore the change if value is not a JSObject or null.
// SpiderMonkey behaves this way.
if (!value->IsJSReceiver() && !value->IsNull()) return value;
// From 8.6.2 Object Internal Methods
// ...
// In addition, if [[Extensible]] is false the value of the [[Class]] and
// [[Prototype]] internal properties of the object may not be modified.
// ...
// Implementation specific extensions that modify [[Class]], [[Prototype]]
// or [[Extensible]] must not violate the invariants defined in the preceding
// paragraph.
if (!object->map()->is_extensible()) {
Handle<Object> args[] = { object };
THROW_NEW_ERROR(isolate, NewTypeError("non_extensible_proto",
HandleVector(args, arraysize(args))),
Object);
}
// Before we can set the prototype we need to be sure
// prototype cycles are prevented.
// It is sufficient to validate that the receiver is not in the new prototype
// chain.
for (PrototypeIterator iter(isolate, *value,
PrototypeIterator::START_AT_RECEIVER);
!iter.IsAtEnd(); iter.Advance()) {
if (JSReceiver::cast(iter.GetCurrent()) == *object) {
// Cycle detected.
THROW_NEW_ERROR(isolate,
NewError("cyclic_proto", HandleVector<Object>(NULL, 0)),
Object);
}
}
bool dictionary_elements_in_chain =
object->map()->DictionaryElementsInPrototypeChainOnly();
Handle<JSObject> real_receiver = object;
if (from_javascript) {
// Find the first object in the chain whose prototype object is not
// hidden and set the new prototype on that object.
PrototypeIterator iter(isolate, real_receiver);
while (!iter.IsAtEnd(PrototypeIterator::END_AT_NON_HIDDEN)) {
real_receiver =
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter));
iter.Advance();
}
}
// Set the new prototype of the object.
Handle<Map> map(real_receiver->map());
// Nothing to do if prototype is already set.
if (map->prototype() == *value) return value;
if (value->IsJSObject()) {
PrototypeOptimizationMode mode =
from_javascript ? REGULAR_PROTOTYPE : FAST_PROTOTYPE;
JSObject::OptimizeAsPrototype(Handle<JSObject>::cast(value), mode);
}
Handle<Map> new_map = Map::TransitionToPrototype(map, value);
DCHECK(new_map->prototype() == *value);
JSObject::MigrateToMap(real_receiver, new_map);
if (!dictionary_elements_in_chain &&
new_map->DictionaryElementsInPrototypeChainOnly()) {
// If the prototype chain didn't previously have element callbacks, then
// KeyedStoreICs need to be cleared to ensure any that involve this
// map go generic.
object->GetHeap()->ClearAllICsByKind(Code::KEYED_STORE_IC);
}
heap->ClearInstanceofCache();
DCHECK(size == object->Size());
return value;
}
void JSObject::EnsureCanContainElements(Handle<JSObject> object,
Arguments* args,
uint32_t first_arg,
uint32_t arg_count,
EnsureElementsMode mode) {
// Elements in |Arguments| are ordered backwards (because they're on the
// stack), but the method that's called here iterates over them in forward
// direction.
return EnsureCanContainElements(
object, args->arguments() - first_arg - (arg_count - 1), arg_count, mode);
}
MaybeHandle<AccessorPair> JSObject::GetOwnElementAccessorPair(
Handle<JSObject> object,
uint32_t index) {
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(object->GetIsolate(), object);
if (iter.IsAtEnd()) return MaybeHandle<AccessorPair>();
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return GetOwnElementAccessorPair(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), index);
}
// Check for lookup interceptor.
if (object->HasIndexedInterceptor()) return MaybeHandle<AccessorPair>();
return object->GetElementsAccessor()->GetAccessorPair(object, object, index);
}
MaybeHandle<Object> JSObject::SetElementWithInterceptor(
Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
Isolate* isolate = object->GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc(isolate);
Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
if (!interceptor->setter()->IsUndefined()) {
v8::IndexedPropertySetterCallback setter =
v8::ToCData<v8::IndexedPropertySetterCallback>(interceptor->setter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-set", *object, index));
PropertyCallbackArguments args(isolate, interceptor->data(), *object,
*object);
v8::Handle<v8::Value> result =
args.Call(setter, index, v8::Utils::ToLocal(value));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (!result.IsEmpty()) return value;
}
return SetElementWithoutInterceptor(object, index, value, attributes,
strict_mode,
check_prototype,
set_mode);
}
MaybeHandle<Object> JSObject::GetElementWithCallback(
Handle<JSObject> object,
Handle<Object> receiver,
Handle<Object> structure,
uint32_t index,
Handle<Object> holder) {
Isolate* isolate = object->GetIsolate();
DCHECK(!structure->IsForeign());
// api style callbacks.
if (structure->IsExecutableAccessorInfo()) {
Handle<ExecutableAccessorInfo> data =
Handle<ExecutableAccessorInfo>::cast(structure);
Object* fun_obj = data->getter();
v8::AccessorNameGetterCallback call_fun =
v8::ToCData<v8::AccessorNameGetterCallback>(fun_obj);
if (call_fun == NULL) return isolate->factory()->undefined_value();
Handle<JSObject> holder_handle = Handle<JSObject>::cast(holder);
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> key = isolate->factory()->NumberToString(number);
LOG(isolate, ApiNamedPropertyAccess("load", *holder_handle, *key));
PropertyCallbackArguments
args(isolate, data->data(), *receiver, *holder_handle);
v8::Handle<v8::Value> result = args.Call(call_fun, v8::Utils::ToLocal(key));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (result.IsEmpty()) return isolate->factory()->undefined_value();
Handle<Object> result_internal = v8::Utils::OpenHandle(*result);
result_internal->VerifyApiCallResultType();
// Rebox handle before return.
return handle(*result_internal, isolate);
}
// __defineGetter__ callback
if (structure->IsAccessorPair()) {
Handle<Object> getter(Handle<AccessorPair>::cast(structure)->getter(),
isolate);
if (getter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return GetPropertyWithDefinedGetter(
receiver, Handle<JSReceiver>::cast(getter));
}
// Getter is not a function.
return isolate->factory()->undefined_value();
}
if (structure->IsDeclaredAccessorInfo()) {
return GetDeclaredAccessorProperty(
receiver, Handle<DeclaredAccessorInfo>::cast(structure), isolate);
}
UNREACHABLE();
return MaybeHandle<Object>();
}
MaybeHandle<Object> JSObject::SetElementWithCallback(Handle<JSObject> object,
Handle<Object> structure,
uint32_t index,
Handle<Object> value,
Handle<JSObject> holder,
StrictMode strict_mode) {
Isolate* isolate = object->GetIsolate();
// We should never get here to initialize a const with the hole
// value since a const declaration would conflict with the setter.
DCHECK(!value->IsTheHole());
DCHECK(!structure->IsForeign());
if (structure->IsExecutableAccessorInfo()) {
// api style callbacks
Handle<ExecutableAccessorInfo> data =
Handle<ExecutableAccessorInfo>::cast(structure);
Object* call_obj = data->setter();
v8::AccessorNameSetterCallback call_fun =
v8::ToCData<v8::AccessorNameSetterCallback>(call_obj);
if (call_fun == NULL) return value;
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> key(isolate->factory()->NumberToString(number));
LOG(isolate, ApiNamedPropertyAccess("store", *object, *key));
PropertyCallbackArguments
args(isolate, data->data(), *object, *holder);
args.Call(call_fun,
v8::Utils::ToLocal(key),
v8::Utils::ToLocal(value));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return value;
}
if (structure->IsAccessorPair()) {
Handle<Object> setter(AccessorPair::cast(*structure)->setter(), isolate);
if (setter->IsSpecFunction()) {
// TODO(rossberg): nicer would be to cast to some JSCallable here...
return SetPropertyWithDefinedSetter(
object, Handle<JSReceiver>::cast(setter), value);
} else {
if (strict_mode == SLOPPY) return value;
Handle<Object> key(isolate->factory()->NewNumberFromUint(index));
Handle<Object> args[2] = { key, holder };
THROW_NEW_ERROR(
isolate, NewTypeError("no_setter_in_callback", HandleVector(args, 2)),
Object);
}
}
// TODO(dcarney): Handle correctly.
if (structure->IsDeclaredAccessorInfo()) return value;
UNREACHABLE();
return MaybeHandle<Object>();
}
bool JSObject::HasFastArgumentsElements() {
Heap* heap = GetHeap();
if (!elements()->IsFixedArray()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
if (elements->map() != heap->sloppy_arguments_elements_map()) {
return false;
}
FixedArray* arguments = FixedArray::cast(elements->get(1));
return !arguments->IsDictionary();
}
bool JSObject::HasDictionaryArgumentsElements() {
Heap* heap = GetHeap();
if (!elements()->IsFixedArray()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
if (elements->map() != heap->sloppy_arguments_elements_map()) {
return false;
}
FixedArray* arguments = FixedArray::cast(elements->get(1));
return arguments->IsDictionary();
}
// Adding n elements in fast case is O(n*n).
// Note: revisit design to have dual undefined values to capture absent
// elements.
MaybeHandle<Object> JSObject::SetFastElement(Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
StrictMode strict_mode,
bool check_prototype) {
DCHECK(object->HasFastSmiOrObjectElements() ||
object->HasFastArgumentsElements());
Isolate* isolate = object->GetIsolate();
// Array optimizations rely on the prototype lookups of Array objects always
// returning undefined. If there is a store to the initial prototype object,
// make sure all of these optimizations are invalidated.
if (isolate->is_initial_object_prototype(*object) ||
isolate->is_initial_array_prototype(*object)) {
object->map()->dependent_code()->DeoptimizeDependentCodeGroup(isolate,
DependentCode::kElementsCantBeAddedGroup);
}
Handle<FixedArray> backing_store(FixedArray::cast(object->elements()));
if (backing_store->map() ==
isolate->heap()->sloppy_arguments_elements_map()) {
backing_store = handle(FixedArray::cast(backing_store->get(1)));
} else {
backing_store = EnsureWritableFastElements(object);
}
uint32_t capacity = static_cast<uint32_t>(backing_store->length());
if (check_prototype &&
(index >= capacity || backing_store->get(index)->IsTheHole())) {
bool found;
MaybeHandle<Object> result = SetElementWithCallbackSetterInPrototypes(
object, index, value, &found, strict_mode);
if (found) return result;
}
uint32_t new_capacity = capacity;
// Check if the length property of this object needs to be updated.
uint32_t array_length = 0;
bool must_update_array_length = false;
bool introduces_holes = true;
if (object->IsJSArray()) {
CHECK(Handle<JSArray>::cast(object)->length()->ToArrayIndex(&array_length));
introduces_holes = index > array_length;
if (index >= array_length) {
must_update_array_length = true;
array_length = index + 1;
}
} else {
introduces_holes = index >= capacity;
}
// If the array is growing, and it's not growth by a single element at the
// end, make sure that the ElementsKind is HOLEY.
ElementsKind elements_kind = object->GetElementsKind();
if (introduces_holes &&
IsFastElementsKind(elements_kind) &&
!IsFastHoleyElementsKind(elements_kind)) {
ElementsKind transitioned_kind = GetHoleyElementsKind(elements_kind);
TransitionElementsKind(object, transitioned_kind);
}
// Check if the capacity of the backing store needs to be increased, or if
// a transition to slow elements is necessary.
if (index >= capacity) {
bool convert_to_slow = true;
if ((index - capacity) < kMaxGap) {
new_capacity = NewElementsCapacity(index + 1);
DCHECK(new_capacity > index);
if (!object->ShouldConvertToSlowElements(new_capacity)) {
convert_to_slow = false;
}
}
if (convert_to_slow) {
NormalizeElements(object);
return SetDictionaryElement(object, index, value, NONE, strict_mode,
check_prototype);
}
}
// Convert to fast double elements if appropriate.
if (object->HasFastSmiElements() && !value->IsSmi() && value->IsNumber()) {
// Consider fixing the boilerplate as well if we have one.
ElementsKind to_kind = IsHoleyElementsKind(elements_kind)
? FAST_HOLEY_DOUBLE_ELEMENTS
: FAST_DOUBLE_ELEMENTS;
UpdateAllocationSite(object, to_kind);
SetFastDoubleElementsCapacityAndLength(object, new_capacity, array_length);
FixedDoubleArray::cast(object->elements())->set(index, value->Number());
JSObject::ValidateElements(object);
return value;
}
// Change elements kind from Smi-only to generic FAST if necessary.
if (object->HasFastSmiElements() && !value->IsSmi()) {
ElementsKind kind = object->HasFastHoleyElements()
? FAST_HOLEY_ELEMENTS
: FAST_ELEMENTS;
UpdateAllocationSite(object, kind);
Handle<Map> new_map = GetElementsTransitionMap(object, kind);
JSObject::MigrateToMap(object, new_map);
DCHECK(IsFastObjectElementsKind(object->GetElementsKind()));
}
// Increase backing store capacity if that's been decided previously.
if (new_capacity != capacity) {
SetFastElementsCapacitySmiMode smi_mode =
value->IsSmi() && object->HasFastSmiElements()
? kAllowSmiElements
: kDontAllowSmiElements;
Handle<FixedArray> new_elements =
SetFastElementsCapacityAndLength(object, new_capacity, array_length,
smi_mode);
new_elements->set(index, *value);
JSObject::ValidateElements(object);
return value;
}
// Finally, set the new element and length.
DCHECK(object->elements()->IsFixedArray());
backing_store->set(index, *value);
if (must_update_array_length) {
Handle<JSArray>::cast(object)->set_length(Smi::FromInt(array_length));
}
return value;
}
MaybeHandle<Object> JSObject::SetDictionaryElement(
Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
DCHECK(object->HasDictionaryElements() ||
object->HasDictionaryArgumentsElements());
Isolate* isolate = object->GetIsolate();
// Insert element in the dictionary.
Handle<FixedArray> elements(FixedArray::cast(object->elements()));
bool is_arguments =
(elements->map() == isolate->heap()->sloppy_arguments_elements_map());
Handle<SeededNumberDictionary> dictionary(is_arguments
? SeededNumberDictionary::cast(elements->get(1))
: SeededNumberDictionary::cast(*elements));
int entry = dictionary->FindEntry(index);
if (entry != SeededNumberDictionary::kNotFound) {
Handle<Object> element(dictionary->ValueAt(entry), isolate);
PropertyDetails details = dictionary->DetailsAt(entry);
if (details.type() == CALLBACKS && set_mode == SET_PROPERTY) {
return SetElementWithCallback(object, element, index, value, object,
strict_mode);
} else {
dictionary->UpdateMaxNumberKey(index);
// If a value has not been initialized we allow writing to it even if it
// is read-only (a declared const that has not been initialized). If a
// value is being defined we skip attribute checks completely.
if (set_mode == DEFINE_PROPERTY) {
details = PropertyDetails(
attributes, NORMAL, details.dictionary_index());
dictionary->DetailsAtPut(entry, details);
} else if (details.IsReadOnly() && !element->IsTheHole()) {
if (strict_mode == SLOPPY) {
return isolate->factory()->undefined_value();
} else {
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<Object> args[2] = { number, object };
THROW_NEW_ERROR(isolate, NewTypeError("strict_read_only_property",
HandleVector(args, 2)),
Object);
}
}
// Elements of the arguments object in slow mode might be slow aliases.
if (is_arguments && element->IsAliasedArgumentsEntry()) {
Handle<AliasedArgumentsEntry> entry =
Handle<AliasedArgumentsEntry>::cast(element);
Handle<Context> context(Context::cast(elements->get(0)));
int context_index = entry->aliased_context_slot();
DCHECK(!context->get(context_index)->IsTheHole());
context->set(context_index, *value);
// For elements that are still writable we keep slow aliasing.
if (!details.IsReadOnly()) value = element;
}
dictionary->ValueAtPut(entry, *value);
}
} else {
// Index not already used. Look for an accessor in the prototype chain.
// Can cause GC!
if (check_prototype) {
bool found;
MaybeHandle<Object> result = SetElementWithCallbackSetterInPrototypes(
object, index, value, &found, strict_mode);
if (found) return result;
}
// When we set the is_extensible flag to false we always force the
// element into dictionary mode (and force them to stay there).
if (!object->map()->is_extensible()) {
if (strict_mode == SLOPPY) {
return isolate->factory()->undefined_value();
} else {
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<String> name = isolate->factory()->NumberToString(number);
Handle<Object> args[1] = { name };
THROW_NEW_ERROR(isolate, NewTypeError("object_not_extensible",
HandleVector(args, 1)),
Object);
}
}
PropertyDetails details = PropertyDetails(attributes, NORMAL, 0);
Handle<SeededNumberDictionary> new_dictionary =
SeededNumberDictionary::AddNumberEntry(dictionary, index, value,
details);
if (*dictionary != *new_dictionary) {
if (is_arguments) {
elements->set(1, *new_dictionary);
} else {
object->set_elements(*new_dictionary);
}
dictionary = new_dictionary;
}
}
// Update the array length if this JSObject is an array.
if (object->IsJSArray()) {
JSArray::JSArrayUpdateLengthFromIndex(Handle<JSArray>::cast(object), index,
value);
}
// Attempt to put this object back in fast case.
if (object->ShouldConvertToFastElements()) {
uint32_t new_length = 0;
if (object->IsJSArray()) {
CHECK(Handle<JSArray>::cast(object)->length()->ToArrayIndex(&new_length));
} else {
new_length = dictionary->max_number_key() + 1;
}
bool has_smi_only_elements = false;
bool should_convert_to_fast_double_elements =
object->ShouldConvertToFastDoubleElements(&has_smi_only_elements);
SetFastElementsCapacitySmiMode smi_mode =
has_smi_only_elements ? kForceSmiElements : kAllowSmiElements;
if (should_convert_to_fast_double_elements) {
SetFastDoubleElementsCapacityAndLength(object, new_length, new_length);
} else {
SetFastElementsCapacityAndLength(object, new_length, new_length,
smi_mode);
}
JSObject::ValidateElements(object);
#ifdef DEBUG
if (FLAG_trace_normalization) {
OFStream os(stdout);
os << "Object elements are fast case again:\n";
object->Print(os);
}
#endif
}
return value;
}
MaybeHandle<Object> JSObject::SetFastDoubleElement(
Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
StrictMode strict_mode,
bool check_prototype) {
DCHECK(object->HasFastDoubleElements());
Handle<FixedArrayBase> base_elms(FixedArrayBase::cast(object->elements()));
uint32_t elms_length = static_cast<uint32_t>(base_elms->length());
// If storing to an element that isn't in the array, pass the store request
// up the prototype chain before storing in the receiver's elements.
if (check_prototype &&
(index >= elms_length ||
Handle<FixedDoubleArray>::cast(base_elms)->is_the_hole(index))) {
bool found;
MaybeHandle<Object> result = SetElementWithCallbackSetterInPrototypes(
object, index, value, &found, strict_mode);
if (found) return result;
}
// If the value object is not a heap number, switch to fast elements and try
// again.
bool value_is_smi = value->IsSmi();
bool introduces_holes = true;
uint32_t length = elms_length;
if (object->IsJSArray()) {
CHECK(Handle<JSArray>::cast(object)->length()->ToArrayIndex(&length));
introduces_holes = index > length;
} else {
introduces_holes = index >= elms_length;
}
if (!value->IsNumber()) {
SetFastElementsCapacityAndLength(object, elms_length, length,
kDontAllowSmiElements);
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
object->GetIsolate(), result,
SetFastElement(object, index, value, strict_mode, check_prototype),
Object);
JSObject::ValidateElements(object);
return result;
}
double double_value = value_is_smi
? static_cast<double>(Handle<Smi>::cast(value)->value())
: Handle<HeapNumber>::cast(value)->value();
// If the array is growing, and it's not growth by a single element at the
// end, make sure that the ElementsKind is HOLEY.
ElementsKind elements_kind = object->GetElementsKind();
if (introduces_holes && !IsFastHoleyElementsKind(elements_kind)) {
ElementsKind transitioned_kind = GetHoleyElementsKind(elements_kind);
TransitionElementsKind(object, transitioned_kind);
}
// Check whether there is extra space in the fixed array.
if (index < elms_length) {
Handle<FixedDoubleArray> elms(FixedDoubleArray::cast(object->elements()));
elms->set(index, double_value);
if (object->IsJSArray()) {
// Update the length of the array if needed.
uint32_t array_length = 0;
CHECK(
Handle<JSArray>::cast(object)->length()->ToArrayIndex(&array_length));
if (index >= array_length) {
Handle<JSArray>::cast(object)->set_length(Smi::FromInt(index + 1));
}
}
return value;
}
// Allow gap in fast case.
if ((index - elms_length) < kMaxGap) {
// Try allocating extra space.
int new_capacity = NewElementsCapacity(index+1);
if (!object->ShouldConvertToSlowElements(new_capacity)) {
DCHECK(static_cast<uint32_t>(new_capacity) > index);
SetFastDoubleElementsCapacityAndLength(object, new_capacity, index + 1);
FixedDoubleArray::cast(object->elements())->set(index, double_value);
JSObject::ValidateElements(object);
return value;
}
}
// Otherwise default to slow case.
DCHECK(object->HasFastDoubleElements());
DCHECK(object->map()->has_fast_double_elements());
DCHECK(object->elements()->IsFixedDoubleArray() ||
object->elements()->length() == 0);
NormalizeElements(object);
DCHECK(object->HasDictionaryElements());
return SetElement(object, index, value, NONE, strict_mode, check_prototype);
}
MaybeHandle<Object> JSReceiver::SetElement(Handle<JSReceiver> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode) {
if (object->IsJSProxy()) {
return JSProxy::SetElementWithHandler(
Handle<JSProxy>::cast(object), object, index, value, strict_mode);
}
return JSObject::SetElement(
Handle<JSObject>::cast(object), index, value, attributes, strict_mode);
}
MaybeHandle<Object> JSObject::SetOwnElement(Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
StrictMode strict_mode) {
DCHECK(!object->HasExternalArrayElements());
return JSObject::SetElement(object, index, value, NONE, strict_mode, false);
}
MaybeHandle<Object> JSObject::SetElement(Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
Isolate* isolate = object->GetIsolate();
if (object->HasExternalArrayElements() ||
object->HasFixedTypedArrayElements()) {
if (!value->IsNumber() && !value->IsUndefined()) {
ASSIGN_RETURN_ON_EXCEPTION(
isolate, value,
Execution::ToNumber(isolate, value), Object);
}
}
// Check access rights if needed.
if (object->IsAccessCheckNeeded()) {
if (!isolate->MayIndexedAccess(object, index, v8::ACCESS_SET)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_SET);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
return value;
}
}
if (object->IsJSGlobalProxy()) {
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return value;
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return SetElement(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), index,
value, attributes, strict_mode, check_prototype, set_mode);
}
// Don't allow element properties to be redefined for external arrays.
if ((object->HasExternalArrayElements() ||
object->HasFixedTypedArrayElements()) &&
set_mode == DEFINE_PROPERTY) {
Handle<Object> number = isolate->factory()->NewNumberFromUint(index);
Handle<Object> args[] = { object, number };
THROW_NEW_ERROR(isolate, NewTypeError("redef_external_array_element",
HandleVector(args, arraysize(args))),
Object);
}
// Normalize the elements to enable attributes on the property.
if ((attributes & (DONT_DELETE | DONT_ENUM | READ_ONLY)) != 0) {
Handle<SeededNumberDictionary> dictionary = NormalizeElements(object);
// Make sure that we never go back to fast case.
dictionary->set_requires_slow_elements();
}
if (!object->map()->is_observed()) {
return object->HasIndexedInterceptor()
? SetElementWithInterceptor(object, index, value, attributes,
strict_mode, check_prototype, set_mode)
: SetElementWithoutInterceptor(object, index, value, attributes,
strict_mode, check_prototype, set_mode);
}
Maybe<PropertyAttributes> maybe =
JSReceiver::GetOwnElementAttribute(object, index);
if (!maybe.has_value) return MaybeHandle<Object>();
PropertyAttributes old_attributes = maybe.value;
Handle<Object> old_value = isolate->factory()->the_hole_value();
Handle<Object> old_length_handle;
Handle<Object> new_length_handle;
if (old_attributes != ABSENT) {
if (GetOwnElementAccessorPair(object, index).is_null()) {
old_value = Object::GetElement(isolate, object, index).ToHandleChecked();
}
} else if (object->IsJSArray()) {
// Store old array length in case adding an element grows the array.
old_length_handle = handle(Handle<JSArray>::cast(object)->length(),
isolate);
}
// Check for lookup interceptor
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result,
object->HasIndexedInterceptor()
? SetElementWithInterceptor(
object, index, value, attributes,
strict_mode, check_prototype, set_mode)
: SetElementWithoutInterceptor(
object, index, value, attributes,
strict_mode, check_prototype, set_mode),
Object);
Handle<String> name = isolate->factory()->Uint32ToString(index);
maybe = GetOwnElementAttribute(object, index);
if (!maybe.has_value) return MaybeHandle<Object>();
PropertyAttributes new_attributes = maybe.value;
if (old_attributes == ABSENT) {
if (object->IsJSArray() &&
!old_length_handle->SameValue(
Handle<JSArray>::cast(object)->length())) {
new_length_handle = handle(Handle<JSArray>::cast(object)->length(),
isolate);
uint32_t old_length = 0;
uint32_t new_length = 0;
CHECK(old_length_handle->ToArrayIndex(&old_length));
CHECK(new_length_handle->ToArrayIndex(&new_length));
BeginPerformSplice(Handle<JSArray>::cast(object));
EnqueueChangeRecord(object, "add", name, old_value);
EnqueueChangeRecord(object, "update", isolate->factory()->length_string(),
old_length_handle);
EndPerformSplice(Handle<JSArray>::cast(object));
Handle<JSArray> deleted = isolate->factory()->NewJSArray(0);
EnqueueSpliceRecord(Handle<JSArray>::cast(object), old_length, deleted,
new_length - old_length);
} else {
EnqueueChangeRecord(object, "add", name, old_value);
}
} else if (old_value->IsTheHole()) {
EnqueueChangeRecord(object, "reconfigure", name, old_value);
} else {
Handle<Object> new_value =
Object::GetElement(isolate, object, index).ToHandleChecked();
bool value_changed = !old_value->SameValue(*new_value);
if (old_attributes != new_attributes) {
if (!value_changed) old_value = isolate->factory()->the_hole_value();
EnqueueChangeRecord(object, "reconfigure", name, old_value);
} else if (value_changed) {
EnqueueChangeRecord(object, "update", name, old_value);
}
}
return result;
}
MaybeHandle<Object> JSObject::SetElementWithoutInterceptor(
Handle<JSObject> object,
uint32_t index,
Handle<Object> value,
PropertyAttributes attributes,
StrictMode strict_mode,
bool check_prototype,
SetPropertyMode set_mode) {
DCHECK(object->HasDictionaryElements() ||
object->HasDictionaryArgumentsElements() ||
(attributes & (DONT_DELETE | DONT_ENUM | READ_ONLY)) == 0);
Isolate* isolate = object->GetIsolate();
if (FLAG_trace_external_array_abuse &&
IsExternalArrayElementsKind(object->GetElementsKind())) {
CheckArrayAbuse(object, "external elements write", index);
}
if (FLAG_trace_js_array_abuse &&
!IsExternalArrayElementsKind(object->GetElementsKind())) {
if (object->IsJSArray()) {
CheckArrayAbuse(object, "elements write", index, true);
}
}
if (object->IsJSArray() && JSArray::WouldChangeReadOnlyLength(
Handle<JSArray>::cast(object), index)) {
if (strict_mode == SLOPPY) {
return value;
} else {
return JSArray::ReadOnlyLengthError(Handle<JSArray>::cast(object));
}
}
switch (object->GetElementsKind()) {
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
return SetFastElement(object, index, value, strict_mode, check_prototype);
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS:
return SetFastDoubleElement(object, index, value, strict_mode,
check_prototype);
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: { \
Handle<External##Type##Array> array( \
External##Type##Array::cast(object->elements())); \
return External##Type##Array::SetValue(array, index, value); \
} \
case TYPE##_ELEMENTS: { \
Handle<Fixed##Type##Array> array( \
Fixed##Type##Array::cast(object->elements())); \
return Fixed##Type##Array::SetValue(array, index, value); \
}
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
case DICTIONARY_ELEMENTS:
return SetDictionaryElement(object, index, value, attributes, strict_mode,
check_prototype,
set_mode);
case SLOPPY_ARGUMENTS_ELEMENTS: {
Handle<FixedArray> parameter_map(FixedArray::cast(object->elements()));
uint32_t length = parameter_map->length();
Handle<Object> probe = index < length - 2 ?
Handle<Object>(parameter_map->get(index + 2), isolate) :
Handle<Object>();
if (!probe.is_null() && !probe->IsTheHole()) {
Handle<Context> context(Context::cast(parameter_map->get(0)));
int context_index = Handle<Smi>::cast(probe)->value();
DCHECK(!context->get(context_index)->IsTheHole());
context->set(context_index, *value);
// Redefining attributes of an aliased element destroys fast aliasing.
if (set_mode == SET_PROPERTY || attributes == NONE) return value;
parameter_map->set_the_hole(index + 2);
// For elements that are still writable we re-establish slow aliasing.
if ((attributes & READ_ONLY) == 0) {
value = Handle<Object>::cast(
isolate->factory()->NewAliasedArgumentsEntry(context_index));
}
}
Handle<FixedArray> arguments(FixedArray::cast(parameter_map->get(1)));
if (arguments->IsDictionary()) {
return SetDictionaryElement(object, index, value, attributes,
strict_mode,
check_prototype,
set_mode);
} else {
return SetFastElement(object, index, value, strict_mode,
check_prototype);
}
}
}
// All possible cases have been handled above. Add a return to avoid the
// complaints from the compiler.
UNREACHABLE();
return isolate->factory()->null_value();
}
const double AllocationSite::kPretenureRatio = 0.85;
void AllocationSite::ResetPretenureDecision() {
set_pretenure_decision(kUndecided);
set_memento_found_count(0);
set_memento_create_count(0);
}
PretenureFlag AllocationSite::GetPretenureMode() {
PretenureDecision mode = pretenure_decision();
// Zombie objects "decide" to be untenured.
return mode == kTenure ? TENURED : NOT_TENURED;
}
bool AllocationSite::IsNestedSite() {
DCHECK(FLAG_trace_track_allocation_sites);
Object* current = GetHeap()->allocation_sites_list();
while (current->IsAllocationSite()) {
AllocationSite* current_site = AllocationSite::cast(current);
if (current_site->nested_site() == this) {
return true;
}
current = current_site->weak_next();
}
return false;
}
void AllocationSite::DigestTransitionFeedback(Handle<AllocationSite> site,
ElementsKind to_kind) {
Isolate* isolate = site->GetIsolate();
if (site->SitePointsToLiteral() && site->transition_info()->IsJSArray()) {
Handle<JSArray> transition_info =
handle(JSArray::cast(site->transition_info()));
ElementsKind kind = transition_info->GetElementsKind();
// if kind is holey ensure that to_kind is as well.
if (IsHoleyElementsKind(kind)) {
to_kind = GetHoleyElementsKind(to_kind);
}
if (IsMoreGeneralElementsKindTransition(kind, to_kind)) {
// If the array is huge, it's not likely to be defined in a local
// function, so we shouldn't make new instances of it very often.
uint32_t length = 0;
CHECK(transition_info->length()->ToArrayIndex(&length));
if (length <= kMaximumArrayBytesToPretransition) {
if (FLAG_trace_track_allocation_sites) {
bool is_nested = site->IsNestedSite();
PrintF(
"AllocationSite: JSArray %p boilerplate %s updated %s->%s\n",
reinterpret_cast<void*>(*site),
is_nested ? "(nested)" : "",
ElementsKindToString(kind),
ElementsKindToString(to_kind));
}
JSObject::TransitionElementsKind(transition_info, to_kind);
site->dependent_code()->DeoptimizeDependentCodeGroup(
isolate, DependentCode::kAllocationSiteTransitionChangedGroup);
}
}
} else {
ElementsKind kind = site->GetElementsKind();
// if kind is holey ensure that to_kind is as well.
if (IsHoleyElementsKind(kind)) {
to_kind = GetHoleyElementsKind(to_kind);
}
if (IsMoreGeneralElementsKindTransition(kind, to_kind)) {
if (FLAG_trace_track_allocation_sites) {
PrintF("AllocationSite: JSArray %p site updated %s->%s\n",
reinterpret_cast<void*>(*site),
ElementsKindToString(kind),
ElementsKindToString(to_kind));
}
site->SetElementsKind(to_kind);
site->dependent_code()->DeoptimizeDependentCodeGroup(
isolate, DependentCode::kAllocationSiteTransitionChangedGroup);
}
}
}
// static
void AllocationSite::AddDependentCompilationInfo(Handle<AllocationSite> site,
Reason reason,
CompilationInfo* info) {
DependentCode::DependencyGroup group = site->ToDependencyGroup(reason);
Handle<DependentCode> dep(site->dependent_code());
Handle<DependentCode> codes =
DependentCode::Insert(dep, group, info->object_wrapper());
if (*codes != site->dependent_code()) site->set_dependent_code(*codes);
info->dependencies(group)->Add(Handle<HeapObject>(*site), info->zone());
}
const char* AllocationSite::PretenureDecisionName(PretenureDecision decision) {
switch (decision) {
case kUndecided: return "undecided";
case kDontTenure: return "don't tenure";
case kMaybeTenure: return "maybe tenure";
case kTenure: return "tenure";
case kZombie: return "zombie";
default: UNREACHABLE();
}
return NULL;
}
void JSObject::UpdateAllocationSite(Handle<JSObject> object,
ElementsKind to_kind) {
if (!object->IsJSArray()) return;
Heap* heap = object->GetHeap();
if (!heap->InNewSpace(*object)) return;
Handle<AllocationSite> site;
{
DisallowHeapAllocation no_allocation;
AllocationMemento* memento = heap->FindAllocationMemento(*object);
if (memento == NULL) return;
// Walk through to the Allocation Site
site = handle(memento->GetAllocationSite());
}
AllocationSite::DigestTransitionFeedback(site, to_kind);
}
void JSObject::TransitionElementsKind(Handle<JSObject> object,
ElementsKind to_kind) {
ElementsKind from_kind = object->map()->elements_kind();
if (IsFastHoleyElementsKind(from_kind)) {
to_kind = GetHoleyElementsKind(to_kind);
}
if (from_kind == to_kind) return;
// Don't update the site if to_kind isn't fast
if (IsFastElementsKind(to_kind)) {
UpdateAllocationSite(object, to_kind);
}
Isolate* isolate = object->GetIsolate();
if (object->elements() == isolate->heap()->empty_fixed_array() ||
(IsFastSmiOrObjectElementsKind(from_kind) &&
IsFastSmiOrObjectElementsKind(to_kind)) ||
(from_kind == FAST_DOUBLE_ELEMENTS &&
to_kind == FAST_HOLEY_DOUBLE_ELEMENTS)) {
DCHECK(from_kind != TERMINAL_FAST_ELEMENTS_KIND);
// No change is needed to the elements() buffer, the transition
// only requires a map change.
Handle<Map> new_map = GetElementsTransitionMap(object, to_kind);
MigrateToMap(object, new_map);
if (FLAG_trace_elements_transitions) {
Handle<FixedArrayBase> elms(object->elements());
PrintElementsTransition(stdout, object, from_kind, elms, to_kind, elms);
}
return;
}
Handle<FixedArrayBase> elms(object->elements());
uint32_t capacity = static_cast<uint32_t>(elms->length());
uint32_t length = capacity;
if (object->IsJSArray()) {
Object* raw_length = Handle<JSArray>::cast(object)->length();
if (raw_length->IsUndefined()) {
// If length is undefined, then JSArray is being initialized and has no
// elements, assume a length of zero.
length = 0;
} else {
CHECK(raw_length->ToArrayIndex(&length));
}
}
if (IsFastSmiElementsKind(from_kind) &&
IsFastDoubleElementsKind(to_kind)) {
SetFastDoubleElementsCapacityAndLength(object, capacity, length);
JSObject::ValidateElements(object);
return;
}
if (IsFastDoubleElementsKind(from_kind) &&
IsFastObjectElementsKind(to_kind)) {
SetFastElementsCapacityAndLength(object, capacity, length,
kDontAllowSmiElements);
JSObject::ValidateElements(object);
return;
}
// This method should never be called for any other case than the ones
// handled above.
UNREACHABLE();
}
// static
bool Map::IsValidElementsTransition(ElementsKind from_kind,
ElementsKind to_kind) {
// Transitions can't go backwards.
if (!IsMoreGeneralElementsKindTransition(from_kind, to_kind)) {
return false;
}
// Transitions from HOLEY -> PACKED are not allowed.
return !IsFastHoleyElementsKind(from_kind) ||
IsFastHoleyElementsKind(to_kind);
}
void JSArray::JSArrayUpdateLengthFromIndex(Handle<JSArray> array,
uint32_t index,
Handle<Object> value) {
uint32_t old_len = 0;
CHECK(array->length()->ToArrayIndex(&old_len));
// Check to see if we need to update the length. For now, we make
// sure that the length stays within 32-bits (unsigned).
if (index >= old_len && index != 0xffffffff) {
Handle<Object> len = array->GetIsolate()->factory()->NewNumber(
static_cast<double>(index) + 1);
array->set_length(*len);
}
}
bool JSArray::IsReadOnlyLengthDescriptor(Handle<Map> jsarray_map) {
Isolate* isolate = jsarray_map->GetIsolate();
DCHECK(!jsarray_map->is_dictionary_map());
LookupResult lookup(isolate);
Handle<Name> length_string = isolate->factory()->length_string();
jsarray_map->LookupDescriptor(NULL, *length_string, &lookup);
return lookup.IsReadOnly();
}
bool JSArray::WouldChangeReadOnlyLength(Handle<JSArray> array,
uint32_t index) {
uint32_t length = 0;
CHECK(array->length()->ToArrayIndex(&length));
if (length <= index) {
LookupIterator it(array, array->GetIsolate()->factory()->length_string(),
LookupIterator::OWN_SKIP_INTERCEPTOR);
CHECK_NE(LookupIterator::ACCESS_CHECK, it.state());
CHECK(it.IsFound());
CHECK_EQ(LookupIterator::ACCESSOR, it.state());
return it.IsReadOnly();
}
return false;
}
MaybeHandle<Object> JSArray::ReadOnlyLengthError(Handle<JSArray> array) {
Isolate* isolate = array->GetIsolate();
Handle<Name> length = isolate->factory()->length_string();
Handle<Object> args[2] = { length, array };
THROW_NEW_ERROR(isolate, NewTypeError("strict_read_only_property",
HandleVector(args, arraysize(args))),
Object);
}
MaybeHandle<Object> JSObject::GetElementWithInterceptor(
Handle<JSObject> object,
Handle<Object> receiver,
uint32_t index) {
Isolate* isolate = object->GetIsolate();
// Make sure that the top context does not change when doing
// callbacks or interceptor calls.
AssertNoContextChange ncc(isolate);
Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor(), isolate);
if (!interceptor->getter()->IsUndefined()) {
v8::IndexedPropertyGetterCallback getter =
v8::ToCData<v8::IndexedPropertyGetterCallback>(interceptor->getter());
LOG(isolate,
ApiIndexedPropertyAccess("interceptor-indexed-get", *object, index));
PropertyCallbackArguments
args(isolate, interceptor->data(), *receiver, *object);
v8::Handle<v8::Value> result = args.Call(getter, index);
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (!result.IsEmpty()) {
Handle<Object> result_internal = v8::Utils::OpenHandle(*result);
result_internal->VerifyApiCallResultType();
// Rebox handle before return.
return handle(*result_internal, isolate);
}
}
ElementsAccessor* handler = object->GetElementsAccessor();
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, result, handler->Get(receiver, object, index),
Object);
if (!result->IsTheHole()) return result;
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return isolate->factory()->undefined_value();
return Object::GetElementWithReceiver(
isolate, PrototypeIterator::GetCurrent(iter), receiver, index);
}
bool JSObject::HasDenseElements() {
int capacity = 0;
int used = 0;
GetElementsCapacityAndUsage(&capacity, &used);
return (capacity == 0) || (used > (capacity / 2));
}
void JSObject::GetElementsCapacityAndUsage(int* capacity, int* used) {
*capacity = 0;
*used = 0;
FixedArrayBase* backing_store_base = FixedArrayBase::cast(elements());
FixedArray* backing_store = NULL;
switch (GetElementsKind()) {
case SLOPPY_ARGUMENTS_ELEMENTS:
backing_store_base =
FixedArray::cast(FixedArray::cast(backing_store_base)->get(1));
backing_store = FixedArray::cast(backing_store_base);
if (backing_store->IsDictionary()) {
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(backing_store);
*capacity = dictionary->Capacity();
*used = dictionary->NumberOfElements();
break;
}
// Fall through.
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
if (IsJSArray()) {
*capacity = backing_store_base->length();
*used = Smi::cast(JSArray::cast(this)->length())->value();
break;
}
// Fall through if packing is not guaranteed.
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
backing_store = FixedArray::cast(backing_store_base);
*capacity = backing_store->length();
for (int i = 0; i < *capacity; ++i) {
if (!backing_store->get(i)->IsTheHole()) ++(*used);
}
break;
case DICTIONARY_ELEMENTS: {
SeededNumberDictionary* dictionary = element_dictionary();
*capacity = dictionary->Capacity();
*used = dictionary->NumberOfElements();
break;
}
case FAST_DOUBLE_ELEMENTS:
if (IsJSArray()) {
*capacity = backing_store_base->length();
*used = Smi::cast(JSArray::cast(this)->length())->value();
break;
}
// Fall through if packing is not guaranteed.
case FAST_HOLEY_DOUBLE_ELEMENTS: {
*capacity = elements()->length();
if (*capacity == 0) break;
FixedDoubleArray * elms = FixedDoubleArray::cast(elements());
for (int i = 0; i < *capacity; i++) {
if (!elms->is_the_hole(i)) ++(*used);
}
break;
}
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
{
// External arrays are considered 100% used.
FixedArrayBase* external_array = FixedArrayBase::cast(elements());
*capacity = external_array->length();
*used = external_array->length();
break;
}
}
}
bool JSObject::WouldConvertToSlowElements(Handle<Object> key) {
uint32_t index;
if (HasFastElements() && key->ToArrayIndex(&index)) {
Handle<FixedArrayBase> backing_store(FixedArrayBase::cast(elements()));
uint32_t capacity = static_cast<uint32_t>(backing_store->length());
if (index >= capacity) {
if ((index - capacity) >= kMaxGap) return true;
uint32_t new_capacity = NewElementsCapacity(index + 1);
return ShouldConvertToSlowElements(new_capacity);
}
}
return false;
}
bool JSObject::ShouldConvertToSlowElements(int new_capacity) {
STATIC_ASSERT(kMaxUncheckedOldFastElementsLength <=
kMaxUncheckedFastElementsLength);
if (new_capacity <= kMaxUncheckedOldFastElementsLength ||
(new_capacity <= kMaxUncheckedFastElementsLength &&
GetHeap()->InNewSpace(this))) {
return false;
}
// If the fast-case backing storage takes up roughly three times as
// much space (in machine words) as a dictionary backing storage
// would, the object should have slow elements.
int old_capacity = 0;
int used_elements = 0;
GetElementsCapacityAndUsage(&old_capacity, &used_elements);
int dictionary_size = SeededNumberDictionary::ComputeCapacity(used_elements) *
SeededNumberDictionary::kEntrySize;
return 3 * dictionary_size <= new_capacity;
}
bool JSObject::ShouldConvertToFastElements() {
DCHECK(HasDictionaryElements() || HasDictionaryArgumentsElements());
// If the elements are sparse, we should not go back to fast case.
if (!HasDenseElements()) return false;
// An object requiring access checks is never allowed to have fast
// elements. If it had fast elements we would skip security checks.
if (IsAccessCheckNeeded()) return false;
// Observed objects may not go to fast mode because they rely on map checks,
// and for fast element accesses we sometimes check element kinds only.
if (map()->is_observed()) return false;
FixedArray* elements = FixedArray::cast(this->elements());
SeededNumberDictionary* dictionary = NULL;
if (elements->map() == GetHeap()->sloppy_arguments_elements_map()) {
dictionary = SeededNumberDictionary::cast(elements->get(1));
} else {
dictionary = SeededNumberDictionary::cast(elements);
}
// If an element has been added at a very high index in the elements
// dictionary, we cannot go back to fast case.
if (dictionary->requires_slow_elements()) return false;
// If the dictionary backing storage takes up roughly half as much
// space (in machine words) as a fast-case backing storage would,
// the object should have fast elements.
uint32_t array_size = 0;
if (IsJSArray()) {
CHECK(JSArray::cast(this)->length()->ToArrayIndex(&array_size));
} else {
array_size = dictionary->max_number_key();
}
uint32_t dictionary_size = static_cast<uint32_t>(dictionary->Capacity()) *
SeededNumberDictionary::kEntrySize;
return 2 * dictionary_size >= array_size;
}
bool JSObject::ShouldConvertToFastDoubleElements(
bool* has_smi_only_elements) {
*has_smi_only_elements = false;
if (HasSloppyArgumentsElements()) return false;
if (FLAG_unbox_double_arrays) {
DCHECK(HasDictionaryElements());
SeededNumberDictionary* dictionary = element_dictionary();
bool found_double = false;
for (int i = 0; i < dictionary->Capacity(); i++) {
Object* key = dictionary->KeyAt(i);
if (key->IsNumber()) {
Object* value = dictionary->ValueAt(i);
if (!value->IsNumber()) return false;
if (!value->IsSmi()) {
found_double = true;
}
}
}
*has_smi_only_elements = !found_double;
return found_double;
} else {
return false;
}
}
// Certain compilers request function template instantiation when they
// see the definition of the other template functions in the
// class. This requires us to have the template functions put
// together, so even though this function belongs in objects-debug.cc,
// we keep it here instead to satisfy certain compilers.
#ifdef OBJECT_PRINT
template <typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::Print(OStream& os) { // NOLINT
int capacity = DerivedHashTable::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = DerivedHashTable::KeyAt(i);
if (DerivedHashTable::IsKey(k)) {
os << " ";
if (k->IsString()) {
String::cast(k)->StringPrint(os);
} else {
os << Brief(k);
}
os << ": " << Brief(ValueAt(i)) << "\n";
}
}
}
#endif
template<typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::CopyValuesTo(FixedArray* elements) {
int pos = 0;
int capacity = DerivedHashTable::Capacity();
DisallowHeapAllocation no_gc;
WriteBarrierMode mode = elements->GetWriteBarrierMode(no_gc);
for (int i = 0; i < capacity; i++) {
Object* k = Dictionary::KeyAt(i);
if (Dictionary::IsKey(k)) {
elements->set(pos++, ValueAt(i), mode);
}
}
DCHECK(pos == elements->length());
}
InterceptorInfo* JSObject::GetNamedInterceptor() {
DCHECK(map()->has_named_interceptor());
JSFunction* constructor = JSFunction::cast(map()->constructor());
DCHECK(constructor->shared()->IsApiFunction());
Object* result =
constructor->shared()->get_api_func_data()->named_property_handler();
return InterceptorInfo::cast(result);
}
InterceptorInfo* JSObject::GetIndexedInterceptor() {
DCHECK(map()->has_indexed_interceptor());
JSFunction* constructor = JSFunction::cast(map()->constructor());
DCHECK(constructor->shared()->IsApiFunction());
Object* result =
constructor->shared()->get_api_func_data()->indexed_property_handler();
return InterceptorInfo::cast(result);
}
MaybeHandle<Object> JSObject::GetPropertyWithInterceptor(
Handle<JSObject> holder,
Handle<Object> receiver,
Handle<Name> name) {
Isolate* isolate = holder->GetIsolate();
// TODO(rossberg): Support symbols in the API.
if (name->IsSymbol()) return isolate->factory()->undefined_value();
Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor(), isolate);
Handle<String> name_string = Handle<String>::cast(name);
if (interceptor->getter()->IsUndefined()) return MaybeHandle<Object>();
v8::NamedPropertyGetterCallback getter =
v8::ToCData<v8::NamedPropertyGetterCallback>(interceptor->getter());
LOG(isolate,
ApiNamedPropertyAccess("interceptor-named-get", *holder, *name));
PropertyCallbackArguments
args(isolate, interceptor->data(), *receiver, *holder);
v8::Handle<v8::Value> result =
args.Call(getter, v8::Utils::ToLocal(name_string));
RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
if (result.IsEmpty()) return MaybeHandle<Object>();
Handle<Object> result_internal = v8::Utils::OpenHandle(*result);
result_internal->VerifyApiCallResultType();
// Rebox handle before return
return handle(*result_internal, isolate);
}
// Compute the property keys from the interceptor.
// TODO(rossberg): support symbols in API, and filter here if needed.
MaybeHandle<JSObject> JSObject::GetKeysForNamedInterceptor(
Handle<JSObject> object, Handle<JSReceiver> receiver) {
Isolate* isolate = receiver->GetIsolate();
Handle<InterceptorInfo> interceptor(object->GetNamedInterceptor());
PropertyCallbackArguments
args(isolate, interceptor->data(), *receiver, *object);
v8::Handle<v8::Object> result;
if (!interceptor->enumerator()->IsUndefined()) {
v8::NamedPropertyEnumeratorCallback enum_fun =
v8::ToCData<v8::NamedPropertyEnumeratorCallback>(
interceptor->enumerator());
LOG(isolate, ApiObjectAccess("interceptor-named-enum", *object));
result = args.Call(enum_fun);
}
if (result.IsEmpty()) return MaybeHandle<JSObject>();
#if ENABLE_EXTRA_CHECKS
CHECK(v8::Utils::OpenHandle(*result)->IsJSArray() ||
v8::Utils::OpenHandle(*result)->HasSloppyArgumentsElements());
#endif
// Rebox before returning.
return handle(*v8::Utils::OpenHandle(*result), isolate);
}
// Compute the element keys from the interceptor.
MaybeHandle<JSObject> JSObject::GetKeysForIndexedInterceptor(
Handle<JSObject> object, Handle<JSReceiver> receiver) {
Isolate* isolate = receiver->GetIsolate();
Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
PropertyCallbackArguments
args(isolate, interceptor->data(), *receiver, *object);
v8::Handle<v8::Object> result;
if (!interceptor->enumerator()->IsUndefined()) {
v8::IndexedPropertyEnumeratorCallback enum_fun =
v8::ToCData<v8::IndexedPropertyEnumeratorCallback>(
interceptor->enumerator());
LOG(isolate, ApiObjectAccess("interceptor-indexed-enum", *object));
result = args.Call(enum_fun);
}
if (result.IsEmpty()) return MaybeHandle<JSObject>();
#if ENABLE_EXTRA_CHECKS
CHECK(v8::Utils::OpenHandle(*result)->IsJSArray() ||
v8::Utils::OpenHandle(*result)->HasSloppyArgumentsElements());
#endif
// Rebox before returning.
return handle(*v8::Utils::OpenHandle(*result), isolate);
}
Maybe<bool> JSObject::HasRealNamedProperty(Handle<JSObject> object,
Handle<Name> key) {
LookupIterator it(object, key, LookupIterator::OWN_SKIP_INTERCEPTOR);
Maybe<PropertyAttributes> maybe_result = GetPropertyAttributes(&it);
if (!maybe_result.has_value) return Maybe<bool>();
return maybe(it.IsFound());
}
Maybe<bool> JSObject::HasRealElementProperty(Handle<JSObject> object,
uint32_t index) {
Isolate* isolate = object->GetIsolate();
HandleScope scope(isolate);
// Check access rights if needed.
if (object->IsAccessCheckNeeded()) {
if (!isolate->MayIndexedAccess(object, index, v8::ACCESS_HAS)) {
isolate->ReportFailedAccessCheck(object, v8::ACCESS_HAS);
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Maybe<bool>());
return maybe(false);
}
}
if (object->IsJSGlobalProxy()) {
HandleScope scope(isolate);
PrototypeIterator iter(isolate, object);
if (iter.IsAtEnd()) return maybe(false);
DCHECK(PrototypeIterator::GetCurrent(iter)->IsJSGlobalObject());
return HasRealElementProperty(
Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)), index);
}
Maybe<PropertyAttributes> result =
GetElementAttributeWithoutInterceptor(object, object, index, false);
if (!result.has_value) return Maybe<bool>();
return maybe(result.value != ABSENT);
}
Maybe<bool> JSObject::HasRealNamedCallbackProperty(Handle<JSObject> object,
Handle<Name> key) {
LookupIterator it(object, key, LookupIterator::OWN_SKIP_INTERCEPTOR);
Maybe<PropertyAttributes> maybe_result = GetPropertyAttributes(&it);
if (!maybe_result.has_value) return Maybe<bool>();
return maybe(it.state() == LookupIterator::ACCESSOR);
}
int JSObject::NumberOfOwnProperties(PropertyAttributes filter) {
if (HasFastProperties()) {
Map* map = this->map();
if (filter == NONE) return map->NumberOfOwnDescriptors();
if (filter & DONT_ENUM) {
int result = map->EnumLength();
if (result != kInvalidEnumCacheSentinel) return result;
}
return map->NumberOfDescribedProperties(OWN_DESCRIPTORS, filter);
}
return property_dictionary()->NumberOfElementsFilterAttributes(filter);
}
void FixedArray::SwapPairs(FixedArray* numbers, int i, int j) {
Object* temp = get(i);
set(i, get(j));
set(j, temp);
if (this != numbers) {
temp = numbers->get(i);
numbers->set(i, Smi::cast(numbers->get(j)));
numbers->set(j, Smi::cast(temp));
}
}
static void InsertionSortPairs(FixedArray* content,
FixedArray* numbers,
int len) {
for (int i = 1; i < len; i++) {
int j = i;
while (j > 0 &&
(NumberToUint32(numbers->get(j - 1)) >
NumberToUint32(numbers->get(j)))) {
content->SwapPairs(numbers, j - 1, j);
j--;
}
}
}
void HeapSortPairs(FixedArray* content, FixedArray* numbers, int len) {
// In-place heap sort.
DCHECK(content->length() == numbers->length());
// Bottom-up max-heap construction.
for (int i = 1; i < len; ++i) {
int child_index = i;
while (child_index > 0) {
int parent_index = ((child_index + 1) >> 1) - 1;
uint32_t parent_value = NumberToUint32(numbers->get(parent_index));
uint32_t child_value = NumberToUint32(numbers->get(child_index));
if (parent_value < child_value) {
content->SwapPairs(numbers, parent_index, child_index);
} else {
break;
}
child_index = parent_index;
}
}
// Extract elements and create sorted array.
for (int i = len - 1; i > 0; --i) {
// Put max element at the back of the array.
content->SwapPairs(numbers, 0, i);
// Sift down the new top element.
int parent_index = 0;
while (true) {
int child_index = ((parent_index + 1) << 1) - 1;
if (child_index >= i) break;
uint32_t child1_value = NumberToUint32(numbers->get(child_index));
uint32_t child2_value = NumberToUint32(numbers->get(child_index + 1));
uint32_t parent_value = NumberToUint32(numbers->get(parent_index));
if (child_index + 1 >= i || child1_value > child2_value) {
if (parent_value > child1_value) break;
content->SwapPairs(numbers, parent_index, child_index);
parent_index = child_index;
} else {
if (parent_value > child2_value) break;
content->SwapPairs(numbers, parent_index, child_index + 1);
parent_index = child_index + 1;
}
}
}
}
// Sort this array and the numbers as pairs wrt. the (distinct) numbers.
void FixedArray::SortPairs(FixedArray* numbers, uint32_t len) {
DCHECK(this->length() == numbers->length());
// For small arrays, simply use insertion sort.
if (len <= 10) {
InsertionSortPairs(this, numbers, len);
return;
}
// Check the range of indices.
uint32_t min_index = NumberToUint32(numbers->get(0));
uint32_t max_index = min_index;
uint32_t i;
for (i = 1; i < len; i++) {
if (NumberToUint32(numbers->get(i)) < min_index) {
min_index = NumberToUint32(numbers->get(i));
} else if (NumberToUint32(numbers->get(i)) > max_index) {
max_index = NumberToUint32(numbers->get(i));
}
}
if (max_index - min_index + 1 == len) {
// Indices form a contiguous range, unless there are duplicates.
// Do an in-place linear time sort assuming distinct numbers, but
// avoid hanging in case they are not.
for (i = 0; i < len; i++) {
uint32_t p;
uint32_t j = 0;
// While the current element at i is not at its correct position p,
// swap the elements at these two positions.
while ((p = NumberToUint32(numbers->get(i)) - min_index) != i &&
j++ < len) {
SwapPairs(numbers, i, p);
}
}
} else {
HeapSortPairs(this, numbers, len);
return;
}
}
// Fill in the names of own properties into the supplied storage. The main
// purpose of this function is to provide reflection information for the object
// mirrors.
void JSObject::GetOwnPropertyNames(
FixedArray* storage, int index, PropertyAttributes filter) {
DCHECK(storage->length() >= (NumberOfOwnProperties(filter) - index));
if (HasFastProperties()) {
int real_size = map()->NumberOfOwnDescriptors();
DescriptorArray* descs = map()->instance_descriptors();
for (int i = 0; i < real_size; i++) {
if ((descs->GetDetails(i).attributes() & filter) == 0 &&
!FilterKey(descs->GetKey(i), filter)) {
storage->set(index++, descs->GetKey(i));
}
}
} else {
property_dictionary()->CopyKeysTo(storage,
index,
filter,
NameDictionary::UNSORTED);
}
}
int JSObject::NumberOfOwnElements(PropertyAttributes filter) {
return GetOwnElementKeys(NULL, filter);
}
int JSObject::NumberOfEnumElements() {
// Fast case for objects with no elements.
if (!IsJSValue() && HasFastObjectElements()) {
uint32_t length = IsJSArray() ?
static_cast<uint32_t>(
Smi::cast(JSArray::cast(this)->length())->value()) :
static_cast<uint32_t>(FixedArray::cast(elements())->length());
if (length == 0) return 0;
}
// Compute the number of enumerable elements.
return NumberOfOwnElements(static_cast<PropertyAttributes>(DONT_ENUM));
}
int JSObject::GetOwnElementKeys(FixedArray* storage,
PropertyAttributes filter) {
int counter = 0;
switch (GetElementsKind()) {
case FAST_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_HOLEY_ELEMENTS: {
int length = IsJSArray() ?
Smi::cast(JSArray::cast(this)->length())->value() :
FixedArray::cast(elements())->length();
for (int i = 0; i < length; i++) {
if (!FixedArray::cast(elements())->get(i)->IsTheHole()) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(i));
}
counter++;
}
}
DCHECK(!storage || storage->length() >= counter);
break;
}
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS: {
int length = IsJSArray() ?
Smi::cast(JSArray::cast(this)->length())->value() :
FixedArrayBase::cast(elements())->length();
for (int i = 0; i < length; i++) {
if (!FixedDoubleArray::cast(elements())->is_the_hole(i)) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(i));
}
counter++;
}
}
DCHECK(!storage || storage->length() >= counter);
break;
}
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ELEMENTS: \
case TYPE##_ELEMENTS: \
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
{
int length = FixedArrayBase::cast(elements())->length();
while (counter < length) {
if (storage != NULL) {
storage->set(counter, Smi::FromInt(counter));
}
counter++;
}
DCHECK(!storage || storage->length() >= counter);
break;
}
case DICTIONARY_ELEMENTS: {
if (storage != NULL) {
element_dictionary()->CopyKeysTo(storage,
filter,
SeededNumberDictionary::SORTED);
}
counter += element_dictionary()->NumberOfElementsFilterAttributes(filter);
break;
}
case SLOPPY_ARGUMENTS_ELEMENTS: {
FixedArray* parameter_map = FixedArray::cast(elements());
int mapped_length = parameter_map->length() - 2;
FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
if (arguments->IsDictionary()) {
// Copy the keys from arguments first, because Dictionary::CopyKeysTo
// will insert in storage starting at index 0.
SeededNumberDictionary* dictionary =
SeededNumberDictionary::cast(arguments);
if (storage != NULL) {
dictionary->CopyKeysTo(
storage, filter, SeededNumberDictionary::UNSORTED);
}
counter += dictionary->NumberOfElementsFilterAttributes(filter);
for (int i = 0; i < mapped_length; ++i) {
if (!parameter_map->get(i + 2)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
if (storage != NULL) storage->SortPairs(storage, counter);
} else {
int backing_length = arguments->length();
int i = 0;
for (; i < mapped_length; ++i) {
if (!parameter_map->get(i + 2)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
} else if (i < backing_length && !arguments->get(i)->IsTheHole()) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
for (; i < backing_length; ++i) {
if (storage != NULL) storage->set(counter, Smi::FromInt(i));
++counter;
}
}
break;
}
}
if (this->IsJSValue()) {
Object* val = JSValue::cast(this)->value();
if (val->IsString()) {
String* str = String::cast(val);
if (storage) {
for (int i = 0; i < str->length(); i++) {
storage->set(counter + i, Smi::FromInt(i));
}
}
counter += str->length();
}
}
DCHECK(!storage || storage->length() == counter);
return counter;
}
int JSObject::GetEnumElementKeys(FixedArray* storage) {
return GetOwnElementKeys(storage, static_cast<PropertyAttributes>(DONT_ENUM));
}
// StringSharedKeys are used as keys in the eval cache.
class StringSharedKey : public HashTableKey {
public:
StringSharedKey(Handle<String> source,
Handle<SharedFunctionInfo> shared,
StrictMode strict_mode,
int scope_position)
: source_(source),
shared_(shared),
strict_mode_(strict_mode),
scope_position_(scope_position) { }
bool IsMatch(Object* other) OVERRIDE {
DisallowHeapAllocation no_allocation;
if (!other->IsFixedArray()) return false;
FixedArray* other_array = FixedArray::cast(other);
SharedFunctionInfo* shared = SharedFunctionInfo::cast(other_array->get(0));
if (shared != *shared_) return false;
int strict_unchecked = Smi::cast(other_array->get(2))->value();
DCHECK(strict_unchecked == SLOPPY || strict_unchecked == STRICT);
StrictMode strict_mode = static_cast<StrictMode>(strict_unchecked);
if (strict_mode != strict_mode_) return false;
int scope_position = Smi::cast(other_array->get(3))->value();
if (scope_position != scope_position_) return false;
String* source = String::cast(other_array->get(1));
return source->Equals(*source_);
}
static uint32_t StringSharedHashHelper(String* source,
SharedFunctionInfo* shared,
StrictMode strict_mode,
int scope_position) {
uint32_t hash = source->Hash();
if (shared->HasSourceCode()) {
// Instead of using the SharedFunctionInfo pointer in the hash
// code computation, we use a combination of the hash of the
// script source code and the start position of the calling scope.
// We do this to ensure that the cache entries can survive garbage
// collection.
Script* script(Script::cast(shared->script()));
hash ^= String::cast(script->source())->Hash();
if (strict_mode == STRICT) hash ^= 0x8000;
hash += scope_position;
}
return hash;
}
uint32_t Hash() OVERRIDE {
return StringSharedHashHelper(*source_, *shared_, strict_mode_,
scope_position_);
}
uint32_t HashForObject(Object* obj) OVERRIDE {
DisallowHeapAllocation no_allocation;
FixedArray* other_array = FixedArray::cast(obj);
SharedFunctionInfo* shared = SharedFunctionInfo::cast(other_array->get(0));
String* source = String::cast(other_array->get(1));
int strict_unchecked = Smi::cast(other_array->get(2))->value();
DCHECK(strict_unchecked == SLOPPY || strict_unchecked == STRICT);
StrictMode strict_mode = static_cast<StrictMode>(strict_unchecked);
int scope_position = Smi::cast(other_array->get(3))->value();
return StringSharedHashHelper(
source, shared, strict_mode, scope_position);
}
Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
Handle<FixedArray> array = isolate->factory()->NewFixedArray(4);
array->set(0, *shared_);
array->set(1, *source_);
array->set(2, Smi::FromInt(strict_mode_));
array->set(3, Smi::FromInt(scope_position_));
return array;
}
private:
Handle<String> source_;
Handle<SharedFunctionInfo> shared_;
StrictMode strict_mode_;
int scope_position_;
};
// RegExpKey carries the source and flags of a regular expression as key.
class RegExpKey : public HashTableKey {
public:
RegExpKey(Handle<String> string, JSRegExp::Flags flags)
: string_(string),
flags_(Smi::FromInt(flags.value())) { }
// Rather than storing the key in the hash table, a pointer to the
// stored value is stored where the key should be. IsMatch then
// compares the search key to the found object, rather than comparing
// a key to a key.
bool IsMatch(Object* obj) OVERRIDE {
FixedArray* val = FixedArray::cast(obj);
return string_->Equals(String::cast(val->get(JSRegExp::kSourceIndex)))
&& (flags_ == val->get(JSRegExp::kFlagsIndex));
}
uint32_t Hash() OVERRIDE { return RegExpHash(*string_, flags_); }
Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
// Plain hash maps, which is where regexp keys are used, don't
// use this function.
UNREACHABLE();
return MaybeHandle<Object>().ToHandleChecked();
}
uint32_t HashForObject(Object* obj) OVERRIDE {
FixedArray* val = FixedArray::cast(obj);
return RegExpHash(String::cast(val->get(JSRegExp::kSourceIndex)),
Smi::cast(val->get(JSRegExp::kFlagsIndex)));
}
static uint32_t RegExpHash(String* string, Smi* flags) {
return string->Hash() + flags->value();
}
Handle<String> string_;
Smi* flags_;
};
Handle<Object> OneByteStringKey::AsHandle(Isolate* isolate) {
if (hash_field_ == 0) Hash();
return isolate->factory()->NewOneByteInternalizedString(string_, hash_field_);
}
Handle<Object> TwoByteStringKey::AsHandle(Isolate* isolate) {
if (hash_field_ == 0) Hash();
return isolate->factory()->NewTwoByteInternalizedString(string_, hash_field_);
}
Handle<Object> SeqOneByteSubStringKey::AsHandle(Isolate* isolate) {
if (hash_field_ == 0) Hash();
return isolate->factory()->NewOneByteInternalizedSubString(
string_, from_, length_, hash_field_);
}
bool SeqOneByteSubStringKey::IsMatch(Object* string) {
Vector<const uint8_t> chars(string_->GetChars() + from_, length_);
return String::cast(string)->IsOneByteEqualTo(chars);
}
// InternalizedStringKey carries a string/internalized-string object as key.
class InternalizedStringKey : public HashTableKey {
public:
explicit InternalizedStringKey(Handle<String> string)
: string_(string) { }
virtual bool IsMatch(Object* string) OVERRIDE {
return String::cast(string)->Equals(*string_);
}
virtual uint32_t Hash() OVERRIDE { return string_->Hash(); }
virtual uint32_t HashForObject(Object* other) OVERRIDE {
return String::cast(other)->Hash();
}
virtual Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
// Internalize the string if possible.
MaybeHandle<Map> maybe_map =
isolate->factory()->InternalizedStringMapForString(string_);
Handle<Map> map;
if (maybe_map.ToHandle(&map)) {
string_->set_map_no_write_barrier(*map);
DCHECK(string_->IsInternalizedString());
return string_;
}
// Otherwise allocate a new internalized string.
return isolate->factory()->NewInternalizedStringImpl(
string_, string_->length(), string_->hash_field());
}
static uint32_t StringHash(Object* obj) {
return String::cast(obj)->Hash();
}
Handle<String> string_;
};
template<typename Derived, typename Shape, typename Key>
void HashTable<Derived, Shape, Key>::IteratePrefix(ObjectVisitor* v) {
IteratePointers(v, 0, kElementsStartOffset);
}
template<typename Derived, typename Shape, typename Key>
void HashTable<Derived, Shape, Key>::IterateElements(ObjectVisitor* v) {
IteratePointers(v,
kElementsStartOffset,
kHeaderSize + length() * kPointerSize);
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> HashTable<Derived, Shape, Key>::New(
Isolate* isolate,
int at_least_space_for,
MinimumCapacity capacity_option,
PretenureFlag pretenure) {
DCHECK(0 <= at_least_space_for);
DCHECK(!capacity_option || base::bits::IsPowerOfTwo32(at_least_space_for));
int capacity = (capacity_option == USE_CUSTOM_MINIMUM_CAPACITY)
? at_least_space_for
: ComputeCapacity(at_least_space_for);
if (capacity > HashTable::kMaxCapacity) {
v8::internal::Heap::FatalProcessOutOfMemory("invalid table size", true);
}
Factory* factory = isolate->factory();
int length = EntryToIndex(capacity);
Handle<FixedArray> array = factory->NewFixedArray(length, pretenure);
array->set_map_no_write_barrier(*factory->hash_table_map());
Handle<Derived> table = Handle<Derived>::cast(array);
table->SetNumberOfElements(0);
table->SetNumberOfDeletedElements(0);
table->SetCapacity(capacity);
return table;
}
// Find entry for key otherwise return kNotFound.
int NameDictionary::FindEntry(Handle<Name> key) {
if (!key->IsUniqueName()) {
return DerivedHashTable::FindEntry(key);
}
// Optimized for unique names. Knowledge of the key type allows:
// 1. Move the check if the key is unique out of the loop.
// 2. Avoid comparing hash codes in unique-to-unique comparison.
// 3. Detect a case when a dictionary key is not unique but the key is.
// In case of positive result the dictionary key may be replaced by the
// internalized string with minimal performance penalty. It gives a chance
// to perform further lookups in code stubs (and significant performance
// boost a certain style of code).
// EnsureCapacity will guarantee the hash table is never full.
uint32_t capacity = Capacity();
uint32_t entry = FirstProbe(key->Hash(), capacity);
uint32_t count = 1;
while (true) {
int index = EntryToIndex(entry);
Object* element = get(index);
if (element->IsUndefined()) break; // Empty entry.
if (*key == element) return entry;
if (!element->IsUniqueName() &&
!element->IsTheHole() &&
Name::cast(element)->Equals(*key)) {
// Replace a key that is a non-internalized string by the equivalent
// internalized string for faster further lookups.
set(index, *key);
return entry;
}
DCHECK(element->IsTheHole() || !Name::cast(element)->Equals(*key));
entry = NextProbe(entry, count++, capacity);
}
return kNotFound;
}
template<typename Derived, typename Shape, typename Key>
void HashTable<Derived, Shape, Key>::Rehash(
Handle<Derived> new_table,
Key key) {
DCHECK(NumberOfElements() < new_table->Capacity());
DisallowHeapAllocation no_gc;
WriteBarrierMode mode = new_table->GetWriteBarrierMode(no_gc);
// Copy prefix to new array.
for (int i = kPrefixStartIndex;
i < kPrefixStartIndex + Shape::kPrefixSize;
i++) {
new_table->set(i, get(i), mode);
}
// Rehash the elements.
int capacity = Capacity();
for (int i = 0; i < capacity; i++) {
uint32_t from_index = EntryToIndex(i);
Object* k = get(from_index);
if (IsKey(k)) {
uint32_t hash = HashTable::HashForObject(key, k);
uint32_t insertion_index =
EntryToIndex(new_table->FindInsertionEntry(hash));
for (int j = 0; j < Shape::kEntrySize; j++) {
new_table->set(insertion_index + j, get(from_index + j), mode);
}
}
}
new_table->SetNumberOfElements(NumberOfElements());
new_table->SetNumberOfDeletedElements(0);
}
template<typename Derived, typename Shape, typename Key>
uint32_t HashTable<Derived, Shape, Key>::EntryForProbe(
Key key,
Object* k,
int probe,
uint32_t expected) {
uint32_t hash = HashTable::HashForObject(key, k);
uint32_t capacity = Capacity();
uint32_t entry = FirstProbe(hash, capacity);
for (int i = 1; i < probe; i++) {
if (entry == expected) return expected;
entry = NextProbe(entry, i, capacity);
}
return entry;
}
template<typename Derived, typename Shape, typename Key>
void HashTable<Derived, Shape, Key>::Swap(uint32_t entry1,
uint32_t entry2,
WriteBarrierMode mode) {
int index1 = EntryToIndex(entry1);
int index2 = EntryToIndex(entry2);
Object* temp[Shape::kEntrySize];
for (int j = 0; j < Shape::kEntrySize; j++) {
temp[j] = get(index1 + j);
}
for (int j = 0; j < Shape::kEntrySize; j++) {
set(index1 + j, get(index2 + j), mode);
}
for (int j = 0; j < Shape::kEntrySize; j++) {
set(index2 + j, temp[j], mode);
}
}
template<typename Derived, typename Shape, typename Key>
void HashTable<Derived, Shape, Key>::Rehash(Key key) {
DisallowHeapAllocation no_gc;
WriteBarrierMode mode = GetWriteBarrierMode(no_gc);
uint32_t capacity = Capacity();
bool done = false;
for (int probe = 1; !done; probe++) {
// All elements at entries given by one of the first _probe_ probes
// are placed correctly. Other elements might need to be moved.
done = true;
for (uint32_t current = 0; current < capacity; current++) {
Object* current_key = get(EntryToIndex(current));
if (IsKey(current_key)) {
uint32_t target = EntryForProbe(key, current_key, probe, current);
if (current == target) continue;
Object* target_key = get(EntryToIndex(target));
if (!IsKey(target_key) ||
EntryForProbe(key, target_key, probe, target) != target) {
// Put the current element into the correct position.
Swap(current, target, mode);
// The other element will be processed on the next iteration.
current--;
} else {
// The place for the current element is occupied. Leave the element
// for the next probe.
done = false;
}
}
}
}
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> HashTable<Derived, Shape, Key>::EnsureCapacity(
Handle<Derived> table,
int n,
Key key,
PretenureFlag pretenure) {
Isolate* isolate = table->GetIsolate();
int capacity = table->Capacity();
int nof = table->NumberOfElements() + n;
int nod = table->NumberOfDeletedElements();
// Return if:
// 50% is still free after adding n elements and
// at most 50% of the free elements are deleted elements.
if (nod <= (capacity - nof) >> 1) {
int needed_free = nof >> 1;
if (nof + needed_free <= capacity) return table;
}
const int kMinCapacityForPretenure = 256;
bool should_pretenure = pretenure == TENURED ||
((capacity > kMinCapacityForPretenure) &&
!isolate->heap()->InNewSpace(*table));
Handle<Derived> new_table = HashTable::New(
isolate,
nof * 2,
USE_DEFAULT_MINIMUM_CAPACITY,
should_pretenure ? TENURED : NOT_TENURED);
table->Rehash(new_table, key);
return new_table;
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> HashTable<Derived, Shape, Key>::Shrink(Handle<Derived> table,
Key key) {
int capacity = table->Capacity();
int nof = table->NumberOfElements();
// Shrink to fit the number of elements if only a quarter of the
// capacity is filled with elements.
if (nof > (capacity >> 2)) return table;
// Allocate a new dictionary with room for at least the current
// number of elements. The allocation method will make sure that
// there is extra room in the dictionary for additions. Don't go
// lower than room for 16 elements.
int at_least_room_for = nof;
if (at_least_room_for < 16) return table;
Isolate* isolate = table->GetIsolate();
const int kMinCapacityForPretenure = 256;
bool pretenure =
(at_least_room_for > kMinCapacityForPretenure) &&
!isolate->heap()->InNewSpace(*table);
Handle<Derived> new_table = HashTable::New(
isolate,
at_least_room_for,
USE_DEFAULT_MINIMUM_CAPACITY,
pretenure ? TENURED : NOT_TENURED);
table->Rehash(new_table, key);
return new_table;
}
template<typename Derived, typename Shape, typename Key>
uint32_t HashTable<Derived, Shape, Key>::FindInsertionEntry(uint32_t hash) {
uint32_t capacity = Capacity();
uint32_t entry = FirstProbe(hash, capacity);
uint32_t count = 1;
// EnsureCapacity will guarantee the hash table is never full.
while (true) {
Object* element = KeyAt(entry);
if (element->IsUndefined() || element->IsTheHole()) break;
entry = NextProbe(entry, count++, capacity);
}
return entry;
}
// Force instantiation of template instances class.
// Please note this list is compiler dependent.
template class HashTable<StringTable, StringTableShape, HashTableKey*>;
template class HashTable<CompilationCacheTable,
CompilationCacheShape,
HashTableKey*>;
template class HashTable<MapCache, MapCacheShape, HashTableKey*>;
template class HashTable<ObjectHashTable,
ObjectHashTableShape,
Handle<Object> >;
template class HashTable<WeakHashTable, WeakHashTableShape<2>, Handle<Object> >;
template class Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >;
template class Dictionary<SeededNumberDictionary,
SeededNumberDictionaryShape,
uint32_t>;
template class Dictionary<UnseededNumberDictionary,
UnseededNumberDictionaryShape,
uint32_t>;
template Handle<SeededNumberDictionary>
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
New(Isolate*, int at_least_space_for, PretenureFlag pretenure);
template Handle<UnseededNumberDictionary>
Dictionary<UnseededNumberDictionary, UnseededNumberDictionaryShape, uint32_t>::
New(Isolate*, int at_least_space_for, PretenureFlag pretenure);
template Handle<NameDictionary>
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
New(Isolate*, int n, PretenureFlag pretenure);
template Handle<SeededNumberDictionary>
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
AtPut(Handle<SeededNumberDictionary>, uint32_t, Handle<Object>);
template Handle<UnseededNumberDictionary>
Dictionary<UnseededNumberDictionary, UnseededNumberDictionaryShape, uint32_t>::
AtPut(Handle<UnseededNumberDictionary>, uint32_t, Handle<Object>);
template Object*
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
SlowReverseLookup(Object* value);
template Object*
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
SlowReverseLookup(Object* value);
template void
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
CopyKeysTo(
FixedArray*,
PropertyAttributes,
Dictionary<SeededNumberDictionary,
SeededNumberDictionaryShape,
uint32_t>::SortMode);
template Handle<Object>
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::DeleteProperty(
Handle<NameDictionary>, int, JSObject::DeleteMode);
template Handle<Object>
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
DeleteProperty(Handle<SeededNumberDictionary>, int, JSObject::DeleteMode);
template Handle<NameDictionary>
HashTable<NameDictionary, NameDictionaryShape, Handle<Name> >::
New(Isolate*, int, MinimumCapacity, PretenureFlag);
template Handle<NameDictionary>
HashTable<NameDictionary, NameDictionaryShape, Handle<Name> >::
Shrink(Handle<NameDictionary>, Handle<Name>);
template Handle<SeededNumberDictionary>
HashTable<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
Shrink(Handle<SeededNumberDictionary>, uint32_t);
template void Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
CopyKeysTo(
FixedArray*,
int,
PropertyAttributes,
Dictionary<
NameDictionary, NameDictionaryShape, Handle<Name> >::SortMode);
template int
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
NumberOfElementsFilterAttributes(PropertyAttributes);
template Handle<NameDictionary>
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::Add(
Handle<NameDictionary>, Handle<Name>, Handle<Object>, PropertyDetails);
template void
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
GenerateNewEnumerationIndices(Handle<NameDictionary>);
template int
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
NumberOfElementsFilterAttributes(PropertyAttributes);
template Handle<SeededNumberDictionary>
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
Add(Handle<SeededNumberDictionary>,
uint32_t,
Handle<Object>,
PropertyDetails);
template Handle<UnseededNumberDictionary>
Dictionary<UnseededNumberDictionary, UnseededNumberDictionaryShape, uint32_t>::
Add(Handle<UnseededNumberDictionary>,
uint32_t,
Handle<Object>,
PropertyDetails);
template Handle<SeededNumberDictionary>
Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
EnsureCapacity(Handle<SeededNumberDictionary>, int, uint32_t);
template Handle<UnseededNumberDictionary>
Dictionary<UnseededNumberDictionary, UnseededNumberDictionaryShape, uint32_t>::
EnsureCapacity(Handle<UnseededNumberDictionary>, int, uint32_t);
template Handle<NameDictionary>
Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
EnsureCapacity(Handle<NameDictionary>, int, Handle<Name>);
template
int Dictionary<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
NumberOfEnumElements();
template
int Dictionary<NameDictionary, NameDictionaryShape, Handle<Name> >::
NumberOfEnumElements();
template
int HashTable<SeededNumberDictionary, SeededNumberDictionaryShape, uint32_t>::
FindEntry(uint32_t);
Handle<Object> JSObject::PrepareSlowElementsForSort(
Handle<JSObject> object, uint32_t limit) {
DCHECK(object->HasDictionaryElements());
Isolate* isolate = object->GetIsolate();
// Must stay in dictionary mode, either because of requires_slow_elements,
// or because we are not going to sort (and therefore compact) all of the
// elements.
Handle<SeededNumberDictionary> dict(object->element_dictionary(), isolate);
Handle<SeededNumberDictionary> new_dict =
SeededNumberDictionary::New(isolate, dict->NumberOfElements());
uint32_t pos = 0;
uint32_t undefs = 0;
int capacity = dict->Capacity();
Handle<Smi> bailout(Smi::FromInt(-1), isolate);
// Entry to the new dictionary does not cause it to grow, as we have
// allocated one that is large enough for all entries.
DisallowHeapAllocation no_gc;
for (int i = 0; i < capacity; i++) {
Object* k = dict->KeyAt(i);
if (!dict->IsKey(k)) continue;
DCHECK(k->IsNumber());
DCHECK(!k->IsSmi() || Smi::cast(k)->value() >= 0);
DCHECK(!k->IsHeapNumber() || HeapNumber::cast(k)->value() >= 0);
DCHECK(!k->IsHeapNumber() || HeapNumber::cast(k)->value() <= kMaxUInt32);
HandleScope scope(isolate);
Handle<Object> value(dict->ValueAt(i), isolate);
PropertyDetails details = dict->DetailsAt(i);
if (details.type() == CALLBACKS || details.IsReadOnly()) {
// Bail out and do the sorting of undefineds and array holes in JS.
// Also bail out if the element is not supposed to be moved.
return bailout;
}
uint32_t key = NumberToUint32(k);
if (key < limit) {
if (value->IsUndefined()) {
undefs++;
} else if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return bailout;
} else {
Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
new_dict, pos, value, details);
DCHECK(result.is_identical_to(new_dict));
USE(result);
pos++;
}
} else if (key > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return bailout;
} else {
Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
new_dict, key, value, details);
DCHECK(result.is_identical_to(new_dict));
USE(result);
}
}
uint32_t result = pos;
PropertyDetails no_details = PropertyDetails(NONE, NORMAL, 0);
while (undefs > 0) {
if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
// Adding an entry with the key beyond smi-range requires
// allocation. Bailout.
return bailout;
}
HandleScope scope(isolate);
Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
new_dict, pos, isolate->factory()->undefined_value(), no_details);
DCHECK(result.is_identical_to(new_dict));
USE(result);
pos++;
undefs--;
}
object->set_elements(*new_dict);
AllowHeapAllocation allocate_return_value;
return isolate->factory()->NewNumberFromUint(result);
}
// Collects all defined (non-hole) and non-undefined (array) elements at
// the start of the elements array.
// If the object is in dictionary mode, it is converted to fast elements
// mode.
Handle<Object> JSObject::PrepareElementsForSort(Handle<JSObject> object,
uint32_t limit) {
Isolate* isolate = object->GetIsolate();
if (object->HasSloppyArgumentsElements() ||
object->map()->is_observed()) {
return handle(Smi::FromInt(-1), isolate);
}
if (object->HasDictionaryElements()) {
// Convert to fast elements containing only the existing properties.
// Ordering is irrelevant, since we are going to sort anyway.
Handle<SeededNumberDictionary> dict(object->element_dictionary());
if (object->IsJSArray() || dict->requires_slow_elements() ||
dict->max_number_key() >= limit) {
return JSObject::PrepareSlowElementsForSort(object, limit);
}
// Convert to fast elements.
Handle<Map> new_map =
JSObject::GetElementsTransitionMap(object, FAST_HOLEY_ELEMENTS);
PretenureFlag tenure = isolate->heap()->InNewSpace(*object) ?
NOT_TENURED: TENURED;
Handle<FixedArray> fast_elements =
isolate->factory()->NewFixedArray(dict->NumberOfElements(), tenure);
dict->CopyValuesTo(*fast_elements);
JSObject::ValidateElements(object);
JSObject::SetMapAndElements(object, new_map, fast_elements);
} else if (object->HasExternalArrayElements() ||
object->HasFixedTypedArrayElements()) {
// Typed arrays cannot have holes or undefined elements.
return handle(Smi::FromInt(
FixedArrayBase::cast(object->elements())->length()), isolate);
} else if (!object->HasFastDoubleElements()) {
EnsureWritableFastElements(object);
}
DCHECK(object->HasFastSmiOrObjectElements() ||
object->HasFastDoubleElements());
// Collect holes at the end, undefined before that and the rest at the
// start, and return the number of non-hole, non-undefined values.
Handle<FixedArrayBase> elements_base(object->elements());
uint32_t elements_length = static_cast<uint32_t>(elements_base->length());
if (limit > elements_length) {
limit = elements_length ;
}
if (limit == 0) {
return handle(Smi::FromInt(0), isolate);
}
uint32_t result = 0;
if (elements_base->map() == isolate->heap()->fixed_double_array_map()) {
FixedDoubleArray* elements = FixedDoubleArray::cast(*elements_base);
// Split elements into defined and the_hole, in that order.
unsigned int holes = limit;
// Assume most arrays contain no holes and undefined values, so minimize the
// number of stores of non-undefined, non-the-hole values.
for (unsigned int i = 0; i < holes; i++) {
if (elements->is_the_hole(i)) {
holes--;
} else {
continue;
}
// Position i needs to be filled.
while (holes > i) {
if (elements->is_the_hole(holes)) {
holes--;
} else {
elements->set(i, elements->get_scalar(holes));
break;
}
}
}
result = holes;
while (holes < limit) {
elements->set_the_hole(holes);
holes++;
}
} else {
FixedArray* elements = FixedArray::cast(*elements_base);
DisallowHeapAllocation no_gc;
// Split elements into defined, undefined and the_hole, in that order. Only
// count locations for undefined and the hole, and fill them afterwards.
WriteBarrierMode write_barrier = elements->GetWriteBarrierMode(no_gc);
unsigned int undefs = limit;
unsigned int holes = limit;
// Assume most arrays contain no holes and undefined values, so minimize the
// number of stores of non-undefined, non-the-hole values.
for (unsigned int i = 0; i < undefs; i++) {
Object* current = elements->get(i);
if (current->IsTheHole()) {
holes--;
undefs--;
} else if (current->IsUndefined()) {
undefs--;
} else {
continue;
}
// Position i needs to be filled.
while (undefs > i) {
current = elements->get(undefs);
if (current->IsTheHole()) {
holes--;
undefs--;
} else if (current->IsUndefined()) {
undefs--;
} else {
elements->set(i, current, write_barrier);
break;
}
}
}
result = undefs;
while (undefs < holes) {
elements->set_undefined(undefs);
undefs++;
}
while (holes < limit) {
elements->set_the_hole(holes);
holes++;
}
}
return isolate->factory()->NewNumberFromUint(result);
}
ExternalArrayType JSTypedArray::type() {
switch (elements()->map()->instance_type()) {
#define INSTANCE_TYPE_TO_ARRAY_TYPE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ARRAY_TYPE: \
case FIXED_##TYPE##_ARRAY_TYPE: \
return kExternal##Type##Array;
TYPED_ARRAYS(INSTANCE_TYPE_TO_ARRAY_TYPE)
#undef INSTANCE_TYPE_TO_ARRAY_TYPE
default:
UNREACHABLE();
return static_cast<ExternalArrayType>(-1);
}
}
size_t JSTypedArray::element_size() {
switch (elements()->map()->instance_type()) {
#define INSTANCE_TYPE_TO_ELEMENT_SIZE(Type, type, TYPE, ctype, size) \
case EXTERNAL_##TYPE##_ARRAY_TYPE: \
return size;
TYPED_ARRAYS(INSTANCE_TYPE_TO_ELEMENT_SIZE)
#undef INSTANCE_TYPE_TO_ELEMENT_SIZE
default:
UNREACHABLE();
return 0;
}
}
Handle<Object> ExternalUint8ClampedArray::SetValue(
Handle<ExternalUint8ClampedArray> array,
uint32_t index,
Handle<Object> value) {
uint8_t clamped_value = 0;
if (index < static_cast<uint32_t>(array->length())) {
if (value->IsSmi()) {
int int_value = Handle<Smi>::cast(value)->value();
if (int_value < 0) {
clamped_value = 0;
} else if (int_value > 255) {
clamped_value = 255;
} else {
clamped_value = static_cast<uint8_t>(int_value);
}
} else if (value->IsHeapNumber()) {
double double_value = Handle<HeapNumber>::cast(value)->value();
if (!(double_value > 0)) {
// NaN and less than zero clamp to zero.
clamped_value = 0;
} else if (double_value > 255) {
// Greater than 255 clamp to 255.
clamped_value = 255;
} else {
// Other doubles are rounded to the nearest integer.
clamped_value = static_cast<uint8_t>(lrint(double_value));
}
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
DCHECK(value->IsUndefined());
}
array->set(index, clamped_value);
}
return handle(Smi::FromInt(clamped_value), array->GetIsolate());
}
template<typename ExternalArrayClass, typename ValueType>
static Handle<Object> ExternalArrayIntSetter(
Isolate* isolate,
Handle<ExternalArrayClass> receiver,
uint32_t index,
Handle<Object> value) {
ValueType cast_value = 0;
if (index < static_cast<uint32_t>(receiver->length())) {
if (value->IsSmi()) {
int int_value = Handle<Smi>::cast(value)->value();
cast_value = static_cast<ValueType>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = Handle<HeapNumber>::cast(value)->value();
cast_value = static_cast<ValueType>(DoubleToInt32(double_value));
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
DCHECK(value->IsUndefined());
}
receiver->set(index, cast_value);
}
return isolate->factory()->NewNumberFromInt(cast_value);
}
Handle<Object> ExternalInt8Array::SetValue(Handle<ExternalInt8Array> array,
uint32_t index,
Handle<Object> value) {
return ExternalArrayIntSetter<ExternalInt8Array, int8_t>(
array->GetIsolate(), array, index, value);
}
Handle<Object> ExternalUint8Array::SetValue(Handle<ExternalUint8Array> array,
uint32_t index,
Handle<Object> value) {
return ExternalArrayIntSetter<ExternalUint8Array, uint8_t>(
array->GetIsolate(), array, index, value);
}
Handle<Object> ExternalInt16Array::SetValue(Handle<ExternalInt16Array> array,
uint32_t index,
Handle<Object> value) {
return ExternalArrayIntSetter<ExternalInt16Array, int16_t>(
array->GetIsolate(), array, index, value);
}
Handle<Object> ExternalUint16Array::SetValue(Handle<ExternalUint16Array> array,
uint32_t index,
Handle<Object> value) {
return ExternalArrayIntSetter<ExternalUint16Array, uint16_t>(
array->GetIsolate(), array, index, value);
}
Handle<Object> ExternalInt32Array::SetValue(Handle<ExternalInt32Array> array,
uint32_t index,
Handle<Object> value) {
return ExternalArrayIntSetter<ExternalInt32Array, int32_t>(
array->GetIsolate(), array, index, value);
}
Handle<Object> ExternalUint32Array::SetValue(
Handle<ExternalUint32Array> array,
uint32_t index,
Handle<Object> value) {
uint32_t cast_value = 0;
if (index < static_cast<uint32_t>(array->length())) {
if (value->IsSmi()) {
int int_value = Handle<Smi>::cast(value)->value();
cast_value = static_cast<uint32_t>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = Handle<HeapNumber>::cast(value)->value();
cast_value = static_cast<uint32_t>(DoubleToUint32(double_value));
} else {
// Clamp undefined to zero (default). All other types have been
// converted to a number type further up in the call chain.
DCHECK(value->IsUndefined());
}
array->set(index, cast_value);
}
return array->GetIsolate()->factory()->NewNumberFromUint(cast_value);
}
Handle<Object> ExternalFloat32Array::SetValue(
Handle<ExternalFloat32Array> array,
uint32_t index,
Handle<Object> value) {
float cast_value = static_cast<float>(base::OS::nan_value());
if (index < static_cast<uint32_t>(array->length())) {
if (value->IsSmi()) {
int int_value = Handle<Smi>::cast(value)->value();
cast_value = static_cast<float>(int_value);
} else if (value->IsHeapNumber()) {
double double_value = Handle<HeapNumber>::cast(value)->value();
cast_value = static_cast<float>(double_value);
} else {
// Clamp undefined to NaN (default). All other types have been
// converted to a number type further up in the call chain.
DCHECK(value->IsUndefined());
}
array->set(index, cast_value);
}
return array->GetIsolate()->factory()->NewNumber(cast_value);
}
Handle<Object> ExternalFloat64Array::SetValue(
Handle<ExternalFloat64Array> array,
uint32_t index,
Handle<Object> value) {
double double_value = base::OS::nan_value();
if (index < static_cast<uint32_t>(array->length())) {
if (value->IsNumber()) {
double_value = value->Number();
} else {
// Clamp undefined to NaN (default). All other types have been
// converted to a number type further up in the call chain.
DCHECK(value->IsUndefined());
}
array->set(index, double_value);
}
return array->GetIsolate()->factory()->NewNumber(double_value);
}
Handle<PropertyCell> JSGlobalObject::EnsurePropertyCell(
Handle<JSGlobalObject> global,
Handle<Name> name) {
DCHECK(!global->HasFastProperties());
int entry = global->property_dictionary()->FindEntry(name);
if (entry == NameDictionary::kNotFound) {
Isolate* isolate = global->GetIsolate();
Handle<PropertyCell> cell = isolate->factory()->NewPropertyCell(
isolate->factory()->the_hole_value());
PropertyDetails details(NONE, NORMAL, 0);
details = details.AsDeleted();
Handle<NameDictionary> dictionary = NameDictionary::Add(
handle(global->property_dictionary()), name, cell, details);
global->set_properties(*dictionary);
return cell;
} else {
Object* value = global->property_dictionary()->ValueAt(entry);
DCHECK(value->IsPropertyCell());
return handle(PropertyCell::cast(value));
}
}
// This class is used for looking up two character strings in the string table.
// If we don't have a hit we don't want to waste much time so we unroll the
// string hash calculation loop here for speed. Doesn't work if the two
// characters form a decimal integer, since such strings have a different hash
// algorithm.
class TwoCharHashTableKey : public HashTableKey {
public:
TwoCharHashTableKey(uint16_t c1, uint16_t c2, uint32_t seed)
: c1_(c1), c2_(c2) {
// Char 1.
uint32_t hash = seed;
hash += c1;
hash += hash << 10;
hash ^= hash >> 6;
// Char 2.
hash += c2;
hash += hash << 10;
hash ^= hash >> 6;
// GetHash.
hash += hash << 3;
hash ^= hash >> 11;
hash += hash << 15;
if ((hash & String::kHashBitMask) == 0) hash = StringHasher::kZeroHash;
hash_ = hash;
#ifdef DEBUG
// If this assert fails then we failed to reproduce the two-character
// version of the string hashing algorithm above. One reason could be
// that we were passed two digits as characters, since the hash
// algorithm is different in that case.
uint16_t chars[2] = {c1, c2};
uint32_t check_hash = StringHasher::HashSequentialString(chars, 2, seed);
hash = (hash << String::kHashShift) | String::kIsNotArrayIndexMask;
DCHECK_EQ(static_cast<int32_t>(hash), static_cast<int32_t>(check_hash));
#endif
}
bool IsMatch(Object* o) OVERRIDE {
if (!o->IsString()) return false;
String* other = String::cast(o);
if (other->length() != 2) return false;
if (other->Get(0) != c1_) return false;
return other->Get(1) == c2_;
}
uint32_t Hash() OVERRIDE { return hash_; }
uint32_t HashForObject(Object* key) OVERRIDE {
if (!key->IsString()) return 0;
return String::cast(key)->Hash();
}
Handle<Object> AsHandle(Isolate* isolate) OVERRIDE {
// The TwoCharHashTableKey is only used for looking in the string
// table, not for adding to it.
UNREACHABLE();
return MaybeHandle<Object>().ToHandleChecked();
}
private:
uint16_t c1_;
uint16_t c2_;
uint32_t hash_;
};
MaybeHandle<String> StringTable::InternalizeStringIfExists(
Isolate* isolate,
Handle<String> string) {
if (string->IsInternalizedString()) {
return string;
}
return LookupStringIfExists(isolate, string);
}
MaybeHandle<String> StringTable::LookupStringIfExists(
Isolate* isolate,
Handle<String> string) {
Handle<StringTable> string_table = isolate->factory()->string_table();
InternalizedStringKey key(string);
int entry = string_table->FindEntry(&key);
if (entry == kNotFound) {
return MaybeHandle<String>();
} else {
Handle<String> result(String::cast(string_table->KeyAt(entry)), isolate);
DCHECK(StringShape(*result).IsInternalized());
return result;
}
}
MaybeHandle<String> StringTable::LookupTwoCharsStringIfExists(
Isolate* isolate,
uint16_t c1,
uint16_t c2) {
Handle<StringTable> string_table = isolate->factory()->string_table();
TwoCharHashTableKey key(c1, c2, isolate->heap()->HashSeed());
int entry = string_table->FindEntry(&key);
if (entry == kNotFound) {
return MaybeHandle<String>();
} else {
Handle<String> result(String::cast(string_table->KeyAt(entry)), isolate);
DCHECK(StringShape(*result).IsInternalized());
return result;
}
}
Handle<String> StringTable::LookupString(Isolate* isolate,
Handle<String> string) {
InternalizedStringKey key(string);
return LookupKey(isolate, &key);
}
Handle<String> StringTable::LookupKey(Isolate* isolate, HashTableKey* key) {
Handle<StringTable> table = isolate->factory()->string_table();
int entry = table->FindEntry(key);
// String already in table.
if (entry != kNotFound) {
return handle(String::cast(table->KeyAt(entry)), isolate);
}
// Adding new string. Grow table if needed.
table = StringTable::EnsureCapacity(table, 1, key);
// Create string object.
Handle<Object> string = key->AsHandle(isolate);
// There must be no attempts to internalize strings that could throw
// InvalidStringLength error.
CHECK(!string.is_null());
// Add the new string and return it along with the string table.
entry = table->FindInsertionEntry(key->Hash());
table->set(EntryToIndex(entry), *string);
table->ElementAdded();
isolate->factory()->set_string_table(table);
return Handle<String>::cast(string);
}
Handle<Object> CompilationCacheTable::Lookup(Handle<String> src,
Handle<Context> context) {
Isolate* isolate = GetIsolate();
Handle<SharedFunctionInfo> shared(context->closure()->shared());
StringSharedKey key(src, shared, FLAG_use_strict ? STRICT : SLOPPY,
RelocInfo::kNoPosition);
int entry = FindEntry(&key);
if (entry == kNotFound) return isolate->factory()->undefined_value();
return Handle<Object>(get(EntryToIndex(entry) + 1), isolate);
}
Handle<Object> CompilationCacheTable::LookupEval(
Handle<String> src, Handle<SharedFunctionInfo> outer_info,
StrictMode strict_mode, int scope_position) {
Isolate* isolate = GetIsolate();
// Cache key is the tuple (source, outer shared function info, scope position)
// to unambiguously identify the context chain the cached eval code assumes.
StringSharedKey key(src, outer_info, strict_mode, scope_position);
int entry = FindEntry(&key);
if (entry == kNotFound) return isolate->factory()->undefined_value();
return Handle<Object>(get(EntryToIndex(entry) + 1), isolate);
}
Handle<Object> CompilationCacheTable::LookupRegExp(Handle<String> src,
JSRegExp::Flags flags) {
Isolate* isolate = GetIsolate();
DisallowHeapAllocation no_allocation;
RegExpKey key(src, flags);
int entry = FindEntry(&key);
if (entry == kNotFound) return isolate->factory()->undefined_value();
return Handle<Object>(get(EntryToIndex(entry) + 1), isolate);
}
Handle<CompilationCacheTable> CompilationCacheTable::Put(
Handle<CompilationCacheTable> cache, Handle<String> src,
Handle<Context> context, Handle<Object> value) {
Isolate* isolate = cache->GetIsolate();
Handle<SharedFunctionInfo> shared(context->closure()->shared());
StringSharedKey key(src, shared, FLAG_use_strict ? STRICT : SLOPPY,
RelocInfo::kNoPosition);
cache = EnsureCapacity(cache, 1, &key);
Handle<Object> k = key.AsHandle(isolate);
int entry = cache->FindInsertionEntry(key.Hash());
cache->set(EntryToIndex(entry), *k);
cache->set(EntryToIndex(entry) + 1, *value);
cache->ElementAdded();
return cache;
}
Handle<CompilationCacheTable> CompilationCacheTable::PutEval(
Handle<CompilationCacheTable> cache, Handle<String> src,
Handle<SharedFunctionInfo> outer_info, Handle<SharedFunctionInfo> value,
int scope_position) {
Isolate* isolate = cache->GetIsolate();
StringSharedKey key(src, outer_info, value->strict_mode(), scope_position);
cache = EnsureCapacity(cache, 1, &key);
Handle<Object> k = key.AsHandle(isolate);
int entry = cache->FindInsertionEntry(key.Hash());
cache->set(EntryToIndex(entry), *k);
cache->set(EntryToIndex(entry) + 1, *value);
cache->ElementAdded();
return cache;
}
Handle<CompilationCacheTable> CompilationCacheTable::PutRegExp(
Handle<CompilationCacheTable> cache, Handle<String> src,
JSRegExp::Flags flags, Handle<FixedArray> value) {
RegExpKey key(src, flags);
cache = EnsureCapacity(cache, 1, &key);
int entry = cache->FindInsertionEntry(key.Hash());
// We store the value in the key slot, and compare the search key
// to the stored value with a custon IsMatch function during lookups.
cache->set(EntryToIndex(entry), *value);
cache->set(EntryToIndex(entry) + 1, *value);
cache->ElementAdded();
return cache;
}
void CompilationCacheTable::Remove(Object* value) {
DisallowHeapAllocation no_allocation;
Object* the_hole_value = GetHeap()->the_hole_value();
for (int entry = 0, size = Capacity(); entry < size; entry++) {
int entry_index = EntryToIndex(entry);
int value_index = entry_index + 1;
if (get(value_index) == value) {
NoWriteBarrierSet(this, entry_index, the_hole_value);
NoWriteBarrierSet(this, value_index, the_hole_value);
ElementRemoved();
}
}
return;
}
// StringsKey used for HashTable where key is array of internalized strings.
class StringsKey : public HashTableKey {
public:
explicit StringsKey(Handle<FixedArray> strings) : strings_(strings) { }
bool IsMatch(Object* strings) OVERRIDE {
FixedArray* o = FixedArray::cast(strings);
int len = strings_->length();
if (o->length() != len) return false;
for (int i = 0; i < len; i++) {
if (o->get(i) != strings_->get(i)) return false;
}
return true;
}
uint32_t Hash() OVERRIDE { return HashForObject(*strings_); }
uint32_t HashForObject(Object* obj) OVERRIDE {
FixedArray* strings = FixedArray::cast(obj);
int len = strings->length();
uint32_t hash = 0;
for (int i = 0; i < len; i++) {
hash ^= String::cast(strings->get(i))->Hash();
}
return hash;
}
Handle<Object> AsHandle(Isolate* isolate) OVERRIDE { return strings_; }
private:
Handle<FixedArray> strings_;
};
Object* MapCache::Lookup(FixedArray* array) {
DisallowHeapAllocation no_alloc;
StringsKey key(handle(array));
int entry = FindEntry(&key);
if (entry == kNotFound) return GetHeap()->undefined_value();
return get(EntryToIndex(entry) + 1);
}
Handle<MapCache> MapCache::Put(
Handle<MapCache> map_cache, Handle<FixedArray> array, Handle<Map> value) {
StringsKey key(array);
Handle<MapCache> new_cache = EnsureCapacity(map_cache, 1, &key);
int entry = new_cache->FindInsertionEntry(key.Hash());
new_cache->set(EntryToIndex(entry), *array);
new_cache->set(EntryToIndex(entry) + 1, *value);
new_cache->ElementAdded();
return new_cache;
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> Dictionary<Derived, Shape, Key>::New(
Isolate* isolate,
int at_least_space_for,
PretenureFlag pretenure) {
DCHECK(0 <= at_least_space_for);
Handle<Derived> dict = DerivedHashTable::New(isolate,
at_least_space_for,
USE_DEFAULT_MINIMUM_CAPACITY,
pretenure);
// Initialize the next enumeration index.
dict->SetNextEnumerationIndex(PropertyDetails::kInitialIndex);
return dict;
}
template<typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::GenerateNewEnumerationIndices(
Handle<Derived> dictionary) {
Factory* factory = dictionary->GetIsolate()->factory();
int length = dictionary->NumberOfElements();
// Allocate and initialize iteration order array.
Handle<FixedArray> iteration_order = factory->NewFixedArray(length);
for (int i = 0; i < length; i++) {
iteration_order->set(i, Smi::FromInt(i));
}
// Allocate array with enumeration order.
Handle<FixedArray> enumeration_order = factory->NewFixedArray(length);
// Fill the enumeration order array with property details.
int capacity = dictionary->Capacity();
int pos = 0;
for (int i = 0; i < capacity; i++) {
if (dictionary->IsKey(dictionary->KeyAt(i))) {
int index = dictionary->DetailsAt(i).dictionary_index();
enumeration_order->set(pos++, Smi::FromInt(index));
}
}
// Sort the arrays wrt. enumeration order.
iteration_order->SortPairs(*enumeration_order, enumeration_order->length());
// Overwrite the enumeration_order with the enumeration indices.
for (int i = 0; i < length; i++) {
int index = Smi::cast(iteration_order->get(i))->value();
int enum_index = PropertyDetails::kInitialIndex + i;
enumeration_order->set(index, Smi::FromInt(enum_index));
}
// Update the dictionary with new indices.
capacity = dictionary->Capacity();
pos = 0;
for (int i = 0; i < capacity; i++) {
if (dictionary->IsKey(dictionary->KeyAt(i))) {
int enum_index = Smi::cast(enumeration_order->get(pos++))->value();
PropertyDetails details = dictionary->DetailsAt(i);
PropertyDetails new_details = PropertyDetails(
details.attributes(), details.type(), enum_index);
dictionary->DetailsAtPut(i, new_details);
}
}
// Set the next enumeration index.
dictionary->SetNextEnumerationIndex(PropertyDetails::kInitialIndex+length);
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> Dictionary<Derived, Shape, Key>::EnsureCapacity(
Handle<Derived> dictionary, int n, Key key) {
// Check whether there are enough enumeration indices to add n elements.
if (Shape::kIsEnumerable &&
!PropertyDetails::IsValidIndex(dictionary->NextEnumerationIndex() + n)) {
// If not, we generate new indices for the properties.
GenerateNewEnumerationIndices(dictionary);
}
return DerivedHashTable::EnsureCapacity(dictionary, n, key);
}
template<typename Derived, typename Shape, typename Key>
Handle<Object> Dictionary<Derived, Shape, Key>::DeleteProperty(
Handle<Derived> dictionary,
int entry,
JSObject::DeleteMode mode) {
Factory* factory = dictionary->GetIsolate()->factory();
PropertyDetails details = dictionary->DetailsAt(entry);
// Ignore attributes if forcing a deletion.
if (!details.IsConfigurable() && mode != JSReceiver::FORCE_DELETION) {
return factory->false_value();
}
dictionary->SetEntry(
entry, factory->the_hole_value(), factory->the_hole_value());
dictionary->ElementRemoved();
return factory->true_value();
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> Dictionary<Derived, Shape, Key>::AtPut(
Handle<Derived> dictionary, Key key, Handle<Object> value) {
int entry = dictionary->FindEntry(key);
// If the entry is present set the value;
if (entry != Dictionary::kNotFound) {
dictionary->ValueAtPut(entry, *value);
return dictionary;
}
// Check whether the dictionary should be extended.
dictionary = EnsureCapacity(dictionary, 1, key);
#ifdef DEBUG
USE(Shape::AsHandle(dictionary->GetIsolate(), key));
#endif
PropertyDetails details = PropertyDetails(NONE, NORMAL, 0);
AddEntry(dictionary, key, value, details, dictionary->Hash(key));
return dictionary;
}
template<typename Derived, typename Shape, typename Key>
Handle<Derived> Dictionary<Derived, Shape, Key>::Add(
Handle<Derived> dictionary,
Key key,
Handle<Object> value,
PropertyDetails details) {
// Valdate key is absent.
SLOW_DCHECK((dictionary->FindEntry(key) == Dictionary::kNotFound));
// Check whether the dictionary should be extended.
dictionary = EnsureCapacity(dictionary, 1, key);
AddEntry(dictionary, key, value, details, dictionary->Hash(key));
return dictionary;
}
// Add a key, value pair to the dictionary.
template<typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::AddEntry(
Handle<Derived> dictionary,
Key key,
Handle<Object> value,
PropertyDetails details,
uint32_t hash) {
// Compute the key object.
Handle<Object> k = Shape::AsHandle(dictionary->GetIsolate(), key);
uint32_t entry = dictionary->FindInsertionEntry(hash);
// Insert element at empty or deleted entry
if (!details.IsDeleted() &&
details.dictionary_index() == 0 &&
Shape::kIsEnumerable) {
// Assign an enumeration index to the property and update
// SetNextEnumerationIndex.
int index = dictionary->NextEnumerationIndex();
details = PropertyDetails(details.attributes(), details.type(), index);
dictionary->SetNextEnumerationIndex(index + 1);
}
dictionary->SetEntry(entry, k, value, details);
DCHECK((dictionary->KeyAt(entry)->IsNumber() ||
dictionary->KeyAt(entry)->IsName()));
dictionary->ElementAdded();
}
void SeededNumberDictionary::UpdateMaxNumberKey(uint32_t key) {
DisallowHeapAllocation no_allocation;
// If the dictionary requires slow elements an element has already
// been added at a high index.
if (requires_slow_elements()) return;
// Check if this index is high enough that we should require slow
// elements.
if (key > kRequiresSlowElementsLimit) {
set_requires_slow_elements();
return;
}
// Update max key value.
Object* max_index_object = get(kMaxNumberKeyIndex);
if (!max_index_object->IsSmi() || max_number_key() < key) {
FixedArray::set(kMaxNumberKeyIndex,
Smi::FromInt(key << kRequiresSlowElementsTagSize));
}
}
Handle<SeededNumberDictionary> SeededNumberDictionary::AddNumberEntry(
Handle<SeededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value,
PropertyDetails details) {
dictionary->UpdateMaxNumberKey(key);
SLOW_DCHECK(dictionary->FindEntry(key) == kNotFound);
return Add(dictionary, key, value, details);
}
Handle<UnseededNumberDictionary> UnseededNumberDictionary::AddNumberEntry(
Handle<UnseededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value) {
SLOW_DCHECK(dictionary->FindEntry(key) == kNotFound);
return Add(dictionary, key, value, PropertyDetails(NONE, NORMAL, 0));
}
Handle<SeededNumberDictionary> SeededNumberDictionary::AtNumberPut(
Handle<SeededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value) {
dictionary->UpdateMaxNumberKey(key);
return AtPut(dictionary, key, value);
}
Handle<UnseededNumberDictionary> UnseededNumberDictionary::AtNumberPut(
Handle<UnseededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value) {
return AtPut(dictionary, key, value);
}
Handle<SeededNumberDictionary> SeededNumberDictionary::Set(
Handle<SeededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value,
PropertyDetails details) {
int entry = dictionary->FindEntry(key);
if (entry == kNotFound) {
return AddNumberEntry(dictionary, key, value, details);
}
// Preserve enumeration index.
details = PropertyDetails(details.attributes(),
details.type(),
dictionary->DetailsAt(entry).dictionary_index());
Handle<Object> object_key =
SeededNumberDictionaryShape::AsHandle(dictionary->GetIsolate(), key);
dictionary->SetEntry(entry, object_key, value, details);
return dictionary;
}
Handle<UnseededNumberDictionary> UnseededNumberDictionary::Set(
Handle<UnseededNumberDictionary> dictionary,
uint32_t key,
Handle<Object> value) {
int entry = dictionary->FindEntry(key);
if (entry == kNotFound) return AddNumberEntry(dictionary, key, value);
Handle<Object> object_key =
UnseededNumberDictionaryShape::AsHandle(dictionary->GetIsolate(), key);
dictionary->SetEntry(entry, object_key, value);
return dictionary;
}
template<typename Derived, typename Shape, typename Key>
int Dictionary<Derived, Shape, Key>::NumberOfElementsFilterAttributes(
PropertyAttributes filter) {
int capacity = DerivedHashTable::Capacity();
int result = 0;
for (int i = 0; i < capacity; i++) {
Object* k = DerivedHashTable::KeyAt(i);
if (DerivedHashTable::IsKey(k) && !FilterKey(k, filter)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
PropertyAttributes attr = details.attributes();
if ((attr & filter) == 0) result++;
}
}
return result;
}
template<typename Derived, typename Shape, typename Key>
int Dictionary<Derived, Shape, Key>::NumberOfEnumElements() {
return NumberOfElementsFilterAttributes(
static_cast<PropertyAttributes>(DONT_ENUM | SYMBOLIC));
}
template<typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::CopyKeysTo(
FixedArray* storage,
PropertyAttributes filter,
typename Dictionary<Derived, Shape, Key>::SortMode sort_mode) {
DCHECK(storage->length() >= NumberOfElementsFilterAttributes(filter));
int capacity = DerivedHashTable::Capacity();
int index = 0;
for (int i = 0; i < capacity; i++) {
Object* k = DerivedHashTable::KeyAt(i);
if (DerivedHashTable::IsKey(k) && !FilterKey(k, filter)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
PropertyAttributes attr = details.attributes();
if ((attr & filter) == 0) storage->set(index++, k);
}
}
if (sort_mode == Dictionary::SORTED) {
storage->SortPairs(storage, index);
}
DCHECK(storage->length() >= index);
}
struct EnumIndexComparator {
explicit EnumIndexComparator(NameDictionary* dict) : dict(dict) { }
bool operator() (Smi* a, Smi* b) {
PropertyDetails da(dict->DetailsAt(a->value()));
PropertyDetails db(dict->DetailsAt(b->value()));
return da.dictionary_index() < db.dictionary_index();
}
NameDictionary* dict;
};
void NameDictionary::CopyEnumKeysTo(FixedArray* storage) {
int length = storage->length();
int capacity = Capacity();
int properties = 0;
for (int i = 0; i < capacity; i++) {
Object* k = KeyAt(i);
if (IsKey(k) && !k->IsSymbol()) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted() || details.IsDontEnum()) continue;
storage->set(properties, Smi::FromInt(i));
properties++;
if (properties == length) break;
}
}
CHECK_EQ(length, properties);
EnumIndexComparator cmp(this);
Smi** start = reinterpret_cast<Smi**>(storage->GetFirstElementAddress());
std::sort(start, start + length, cmp);
for (int i = 0; i < length; i++) {
int index = Smi::cast(storage->get(i))->value();
storage->set(i, KeyAt(index));
}
}
template<typename Derived, typename Shape, typename Key>
void Dictionary<Derived, Shape, Key>::CopyKeysTo(
FixedArray* storage,
int index,
PropertyAttributes filter,
typename Dictionary<Derived, Shape, Key>::SortMode sort_mode) {
DCHECK(storage->length() >= NumberOfElementsFilterAttributes(filter));
int capacity = DerivedHashTable::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = DerivedHashTable::KeyAt(i);
if (DerivedHashTable::IsKey(k) && !FilterKey(k, filter)) {
PropertyDetails details = DetailsAt(i);
if (details.IsDeleted()) continue;
PropertyAttributes attr = details.attributes();
if ((attr & filter) == 0) storage->set(index++, k);
}
}
if (sort_mode == Dictionary::SORTED) {
storage->SortPairs(storage, index);
}
DCHECK(storage->length() >= index);
}
// Backwards lookup (slow).
template<typename Derived, typename Shape, typename Key>
Object* Dictionary<Derived, Shape, Key>::SlowReverseLookup(Object* value) {
int capacity = DerivedHashTable::Capacity();
for (int i = 0; i < capacity; i++) {
Object* k = DerivedHashTable::KeyAt(i);
if (Dictionary::IsKey(k)) {
Object* e = ValueAt(i);
if (e->IsPropertyCell()) {
e = PropertyCell::cast(e)->value();
}
if (e == value) return k;
}
}
Heap* heap = Dictionary::GetHeap();
return heap->undefined_value();
}
Object* ObjectHashTable::Lookup(Handle<Object> key) {
DisallowHeapAllocation no_gc;
DCHECK(IsKey(*key));
// If the object does not have an identity hash, it was never used as a key.
Object* hash = key->GetHash();
if (hash->IsUndefined()) {
return GetHeap()->the_hole_value();
}
int entry = FindEntry(key);
if (entry == kNotFound) return GetHeap()->the_hole_value();
return get(EntryToIndex(entry) + 1);
}
Handle<ObjectHashTable> ObjectHashTable::Put(Handle<ObjectHashTable> table,
Handle<Object> key,
Handle<Object> value) {
DCHECK(table->IsKey(*key));
DCHECK(!value->IsTheHole());
Isolate* isolate = table->GetIsolate();
// Make sure the key object has an identity hash code.
Handle<Smi> hash = Object::GetOrCreateHash(isolate, key);
int entry = table->FindEntry(key);
// Key is already in table, just overwrite value.
if (entry != kNotFound) {
table->set(EntryToIndex(entry) + 1, *value);
return table;
}
// Check whether the hash table should be extended.
table = EnsureCapacity(table, 1, key);
table->AddEntry(table->FindInsertionEntry(hash->value()),
*key,
*value);
return table;
}
Handle<ObjectHashTable> ObjectHashTable::Remove(Handle<ObjectHashTable> table,
Handle<Object> key,
bool* was_present) {
DCHECK(table->IsKey(*key));
Object* hash = key->GetHash();
if (hash->IsUndefined()) {
*was_present = false;
return table;
}
int entry = table->FindEntry(key);
if (entry == kNotFound) {
*was_present = false;
return table;
}
*was_present = true;
table->RemoveEntry(entry);
return Shrink(table, key);
}
void ObjectHashTable::AddEntry(int entry, Object* key, Object* value) {
set(EntryToIndex(entry), key);
set(EntryToIndex(entry) + 1, value);
ElementAdded();
}
void ObjectHashTable::RemoveEntry(int entry) {
set_the_hole(EntryToIndex(entry));
set_the_hole(EntryToIndex(entry) + 1);
ElementRemoved();
}
Object* WeakHashTable::Lookup(Handle<Object> key) {
DisallowHeapAllocation no_gc;
DCHECK(IsKey(*key));
int entry = FindEntry(key);
if (entry == kNotFound) return GetHeap()->the_hole_value();
return get(EntryToValueIndex(entry));
}
Handle<WeakHashTable> WeakHashTable::Put(Handle<WeakHashTable> table,
Handle<Object> key,
Handle<Object> value) {
DCHECK(table->IsKey(*key));
int entry = table->FindEntry(key);
// Key is already in table, just overwrite value.
if (entry != kNotFound) {
// TODO(ulan): Skipping write barrier is a temporary solution to avoid
// memory leaks. Remove this once we have special visitor for weak fixed
// arrays.
table->set(EntryToValueIndex(entry), *value, SKIP_WRITE_BARRIER);
return table;
}
// Check whether the hash table should be extended.
table = EnsureCapacity(table, 1, key, TENURED);
table->AddEntry(table->FindInsertionEntry(table->Hash(key)), key, value);
return table;
}
void WeakHashTable::AddEntry(int entry,
Handle<Object> key,
Handle<Object> value) {
DisallowHeapAllocation no_allocation;
// TODO(ulan): Skipping write barrier is a temporary solution to avoid
// memory leaks. Remove this once we have special visitor for weak fixed
// arrays.
set(EntryToIndex(entry), *key, SKIP_WRITE_BARRIER);
set(EntryToValueIndex(entry), *value, SKIP_WRITE_BARRIER);
ElementAdded();
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::Allocate(
Isolate* isolate, int capacity, PretenureFlag pretenure) {
// Capacity must be a power of two, since we depend on being able
// to divide and multiple by 2 (kLoadFactor) to derive capacity
// from number of buckets. If we decide to change kLoadFactor
// to something other than 2, capacity should be stored as another
// field of this object.
capacity = base::bits::RoundUpToPowerOfTwo32(Max(kMinCapacity, capacity));
if (capacity > kMaxCapacity) {
v8::internal::Heap::FatalProcessOutOfMemory("invalid table size", true);
}
int num_buckets = capacity / kLoadFactor;
Handle<FixedArray> backing_store = isolate->factory()->NewFixedArray(
kHashTableStartIndex + num_buckets + (capacity * kEntrySize), pretenure);
backing_store->set_map_no_write_barrier(
isolate->heap()->ordered_hash_table_map());
Handle<Derived> table = Handle<Derived>::cast(backing_store);
for (int i = 0; i < num_buckets; ++i) {
table->set(kHashTableStartIndex + i, Smi::FromInt(kNotFound));
}
table->SetNumberOfBuckets(num_buckets);
table->SetNumberOfElements(0);
table->SetNumberOfDeletedElements(0);
return table;
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::EnsureGrowable(
Handle<Derived> table) {
DCHECK(!table->IsObsolete());
int nof = table->NumberOfElements();
int nod = table->NumberOfDeletedElements();
int capacity = table->Capacity();
if ((nof + nod) < capacity) return table;
// Don't need to grow if we can simply clear out deleted entries instead.
// Note that we can't compact in place, though, so we always allocate
// a new table.
return Rehash(table, (nod < (capacity >> 1)) ? capacity << 1 : capacity);
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::Shrink(
Handle<Derived> table) {
DCHECK(!table->IsObsolete());
int nof = table->NumberOfElements();
int capacity = table->Capacity();
if (nof >= (capacity >> 2)) return table;
return Rehash(table, capacity / 2);
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::Clear(
Handle<Derived> table) {
DCHECK(!table->IsObsolete());
Handle<Derived> new_table =
Allocate(table->GetIsolate(),
kMinCapacity,
table->GetHeap()->InNewSpace(*table) ? NOT_TENURED : TENURED);
table->SetNextTable(*new_table);
table->SetNumberOfDeletedElements(-1);
return new_table;
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::Remove(
Handle<Derived> table, Handle<Object> key, bool* was_present) {
int entry = table->FindEntry(key);
if (entry == kNotFound) {
*was_present = false;
return table;
}
*was_present = true;
table->RemoveEntry(entry);
return Shrink(table);
}
template<class Derived, class Iterator, int entrysize>
Handle<Derived> OrderedHashTable<Derived, Iterator, entrysize>::Rehash(
Handle<Derived> table, int new_capacity) {
DCHECK(!table->IsObsolete());
Handle<Derived> new_table =
Allocate(table->GetIsolate(),
new_capacity,
table->GetHeap()->InNewSpace(*table) ? NOT_TENURED : TENURED);
int nof = table->NumberOfElements();
int nod = table->NumberOfDeletedElements();
int new_buckets = new_table->NumberOfBuckets();
int new_entry = 0;
int removed_holes_index = 0;
for (int old_entry = 0; old_entry < (nof + nod); ++old_entry) {
Object* key = table->KeyAt(old_entry);
if (key->IsTheHole()) {
table->SetRemovedIndexAt(removed_holes_index++, old_entry);
continue;
}
Object* hash = key->GetHash();
int bucket = Smi::cast(hash)->value() & (new_buckets - 1);
Object* chain_entry = new_table->get(kHashTableStartIndex + bucket);
new_table->set(kHashTableStartIndex + bucket, Smi::FromInt(new_entry));
int new_index = new_table->EntryToIndex(new_entry);
int old_index = table->EntryToIndex(old_entry);
for (int i = 0; i < entrysize; ++i) {
Object* value = table->get(old_index + i);
new_table->set(new_index + i, value);
}
new_table->set(new_index + kChainOffset, chain_entry);
++new_entry;
}
DCHECK_EQ(nod, removed_holes_index);
new_table->SetNumberOfElements(nof);
table->SetNextTable(*new_table);
return new_table;
}
template <class Derived, class Iterator, int entrysize>
int OrderedHashTable<Derived, Iterator, entrysize>::FindEntry(
Handle<Object> key, int hash) {
DCHECK(!IsObsolete());
DisallowHeapAllocation no_gc;
DCHECK(!key->IsTheHole());
for (int entry = HashToEntry(hash); entry != kNotFound;
entry = ChainAt(entry)) {
Object* candidate = KeyAt(entry);
if (candidate->SameValueZero(*key))
return entry;
}
return kNotFound;
}
template <class Derived, class Iterator, int entrysize>
int OrderedHashTable<Derived, Iterator, entrysize>::FindEntry(
Handle<Object> key) {
DisallowHeapAllocation no_gc;
Object* hash = key->GetHash();
if (!hash->IsSmi()) return kNotFound;
return FindEntry(key, Smi::cast(hash)->value());
}
template <class Derived, class Iterator, int entrysize>
int OrderedHashTable<Derived, Iterator, entrysize>::AddEntry(int hash) {
DCHECK(!IsObsolete());
int entry = UsedCapacity();
int bucket = HashToBucket(hash);
int index = EntryToIndex(entry);
Object* chain_entry = get(kHashTableStartIndex + bucket);
set(kHashTableStartIndex + bucket, Smi::FromInt(entry));
set(index + kChainOffset, chain_entry);
SetNumberOfElements(NumberOfElements() + 1);
return index;
}
template<class Derived, class Iterator, int entrysize>
void OrderedHashTable<Derived, Iterator, entrysize>::RemoveEntry(int entry) {
DCHECK(!IsObsolete());
int index = EntryToIndex(entry);
for (int i = 0; i < entrysize; ++i) {
set_the_hole(index + i);
}
SetNumberOfElements(NumberOfElements() - 1);
SetNumberOfDeletedElements(NumberOfDeletedElements() + 1);
}
template Handle<OrderedHashSet>
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::Allocate(
Isolate* isolate, int capacity, PretenureFlag pretenure);
template Handle<OrderedHashSet>
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::EnsureGrowable(
Handle<OrderedHashSet> table);
template Handle<OrderedHashSet>
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::Shrink(
Handle<OrderedHashSet> table);
template Handle<OrderedHashSet>
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::Clear(
Handle<OrderedHashSet> table);
template Handle<OrderedHashSet>
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::Remove(
Handle<OrderedHashSet> table, Handle<Object> key, bool* was_present);
template int OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::FindEntry(
Handle<Object> key, int hash);
template int OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::FindEntry(
Handle<Object> key);
template int
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::AddEntry(int hash);
template void
OrderedHashTable<OrderedHashSet, JSSetIterator, 1>::RemoveEntry(int entry);
template Handle<OrderedHashMap>
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::Allocate(
Isolate* isolate, int capacity, PretenureFlag pretenure);
template Handle<OrderedHashMap>
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::EnsureGrowable(
Handle<OrderedHashMap> table);
template Handle<OrderedHashMap>
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::Shrink(
Handle<OrderedHashMap> table);
template Handle<OrderedHashMap>
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::Clear(
Handle<OrderedHashMap> table);
template Handle<OrderedHashMap>
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::Remove(
Handle<OrderedHashMap> table, Handle<Object> key, bool* was_present);
template int OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::FindEntry(
Handle<Object> key, int hash);
template int OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::FindEntry(
Handle<Object> key);
template int
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::AddEntry(int hash);
template void
OrderedHashTable<OrderedHashMap, JSMapIterator, 2>::RemoveEntry(int entry);
bool OrderedHashSet::Contains(Handle<Object> key) {
return FindEntry(key) != kNotFound;
}
Handle<OrderedHashSet> OrderedHashSet::Add(Handle<OrderedHashSet> table,
Handle<Object> key) {
int hash = GetOrCreateHash(table->GetIsolate(), key)->value();
if (table->FindEntry(key, hash) != kNotFound) return table;
table = EnsureGrowable(table);
int index = table->AddEntry(hash);
table->set(index, *key);
return table;
}
Object* OrderedHashMap::Lookup(Handle<Object> key) {
DisallowHeapAllocation no_gc;
int entry = FindEntry(key);
if (entry == kNotFound) return GetHeap()->the_hole_value();
return ValueAt(entry);
}
Handle<OrderedHashMap> OrderedHashMap::Put(Handle<OrderedHashMap> table,
Handle<Object> key,
Handle<Object> value) {
DCHECK(!key->IsTheHole());
int hash = GetOrCreateHash(table->GetIsolate(), key)->value();
int entry = table->FindEntry(key, hash);
if (entry != kNotFound) {
table->set(table->EntryToIndex(entry) + kValueOffset, *value);
return table;
}
table = EnsureGrowable(table);
int index = table->AddEntry(hash);
table->set(index, *key);
table->set(index + kValueOffset, *value);
return table;
}
template<class Derived, class TableType>
void OrderedHashTableIterator<Derived, TableType>::Transition() {
DisallowHeapAllocation no_allocation;
TableType* table = TableType::cast(this->table());
if (!table->IsObsolete()) return;
int index = Smi::cast(this->index())->value();
while (table->IsObsolete()) {
TableType* next_table = table->NextTable();
if (index > 0) {
int nod = table->NumberOfDeletedElements();
// When we clear the table we set the number of deleted elements to -1.
if (nod == -1) {
index = 0;
} else {
int old_index = index;
for (int i = 0; i < nod; ++i) {
int removed_index = table->RemovedIndexAt(i);
if (removed_index >= old_index) break;
--index;
}
}
}
table = next_table;
}
set_table(table);
set_index(Smi::FromInt(index));
}
template<class Derived, class TableType>
bool OrderedHashTableIterator<Derived, TableType>::HasMore() {
DisallowHeapAllocation no_allocation;
if (this->table()->IsUndefined()) return false;
Transition();
TableType* table = TableType::cast(this->table());
int index = Smi::cast(this->index())->value();
int used_capacity = table->UsedCapacity();
while (index < used_capacity && table->KeyAt(index)->IsTheHole()) {
index++;
}
set_index(Smi::FromInt(index));
if (index < used_capacity) return true;
set_table(GetHeap()->undefined_value());
return false;
}
template<class Derived, class TableType>
Smi* OrderedHashTableIterator<Derived, TableType>::Next(JSArray* value_array) {
DisallowHeapAllocation no_allocation;
if (HasMore()) {
FixedArray* array = FixedArray::cast(value_array->elements());
static_cast<Derived*>(this)->PopulateValueArray(array);
MoveNext();
return Smi::cast(kind());
}
return Smi::FromInt(0);
}
template Smi*
OrderedHashTableIterator<JSSetIterator, OrderedHashSet>::Next(
JSArray* value_array);
template bool
OrderedHashTableIterator<JSSetIterator, OrderedHashSet>::HasMore();
template void
OrderedHashTableIterator<JSSetIterator, OrderedHashSet>::MoveNext();
template Object*
OrderedHashTableIterator<JSSetIterator, OrderedHashSet>::CurrentKey();
template void
OrderedHashTableIterator<JSSetIterator, OrderedHashSet>::Transition();
template Smi*
OrderedHashTableIterator<JSMapIterator, OrderedHashMap>::Next(
JSArray* value_array);
template bool
OrderedHashTableIterator<JSMapIterator, OrderedHashMap>::HasMore();
template void
OrderedHashTableIterator<JSMapIterator, OrderedHashMap>::MoveNext();
template Object*
OrderedHashTableIterator<JSMapIterator, OrderedHashMap>::CurrentKey();
template void
OrderedHashTableIterator<JSMapIterator, OrderedHashMap>::Transition();
DeclaredAccessorDescriptorIterator::DeclaredAccessorDescriptorIterator(
DeclaredAccessorDescriptor* descriptor)
: array_(descriptor->serialized_data()->GetDataStartAddress()),
length_(descriptor->serialized_data()->length()),
offset_(0) {
}
const DeclaredAccessorDescriptorData*
DeclaredAccessorDescriptorIterator::Next() {
DCHECK(offset_ < length_);
uint8_t* ptr = &array_[offset_];
DCHECK(reinterpret_cast<uintptr_t>(ptr) % sizeof(uintptr_t) == 0);
const DeclaredAccessorDescriptorData* data =
reinterpret_cast<const DeclaredAccessorDescriptorData*>(ptr);
offset_ += sizeof(*data);
DCHECK(offset_ <= length_);
return data;
}
Handle<DeclaredAccessorDescriptor> DeclaredAccessorDescriptor::Create(
Isolate* isolate,
const DeclaredAccessorDescriptorData& descriptor,
Handle<DeclaredAccessorDescriptor> previous) {
int previous_length =
previous.is_null() ? 0 : previous->serialized_data()->length();
int length = sizeof(descriptor) + previous_length;
Handle<ByteArray> serialized_descriptor =
isolate->factory()->NewByteArray(length);
Handle<DeclaredAccessorDescriptor> value =
isolate->factory()->NewDeclaredAccessorDescriptor();
value->set_serialized_data(*serialized_descriptor);
// Copy in the data.
{
DisallowHeapAllocation no_allocation;
uint8_t* array = serialized_descriptor->GetDataStartAddress();
if (previous_length != 0) {
uint8_t* previous_array =
previous->serialized_data()->GetDataStartAddress();
MemCopy(array, previous_array, previous_length);
array += previous_length;
}
DCHECK(reinterpret_cast<uintptr_t>(array) % sizeof(uintptr_t) == 0);
DeclaredAccessorDescriptorData* data =
reinterpret_cast<DeclaredAccessorDescriptorData*>(array);
*data = descriptor;
}
return value;
}
// Check if there is a break point at this code position.
bool DebugInfo::HasBreakPoint(int code_position) {
// Get the break point info object for this code position.
Object* break_point_info = GetBreakPointInfo(code_position);
// If there is no break point info object or no break points in the break
// point info object there is no break point at this code position.
if (break_point_info->IsUndefined()) return false;
return BreakPointInfo::cast(break_point_info)->GetBreakPointCount() > 0;
}
// Get the break point info object for this code position.
Object* DebugInfo::GetBreakPointInfo(int code_position) {
// Find the index of the break point info object for this code position.
int index = GetBreakPointInfoIndex(code_position);
// Return the break point info object if any.
if (index == kNoBreakPointInfo) return GetHeap()->undefined_value();
return BreakPointInfo::cast(break_points()->get(index));
}
// Clear a break point at the specified code position.
void DebugInfo::ClearBreakPoint(Handle<DebugInfo> debug_info,
int code_position,
Handle<Object> break_point_object) {
Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position),
debug_info->GetIsolate());
if (break_point_info->IsUndefined()) return;
BreakPointInfo::ClearBreakPoint(
Handle<BreakPointInfo>::cast(break_point_info),
break_point_object);
}
void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
int code_position,
int source_position,
int statement_position,
Handle<Object> break_point_object) {
Isolate* isolate = debug_info->GetIsolate();
Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position),
isolate);
if (!break_point_info->IsUndefined()) {
BreakPointInfo::SetBreakPoint(
Handle<BreakPointInfo>::cast(break_point_info),
break_point_object);
return;
}
// Adding a new break point for a code position which did not have any
// break points before. Try to find a free slot.
int index = kNoBreakPointInfo;
for (int i = 0; i < debug_info->break_points()->length(); i++) {
if (debug_info->break_points()->get(i)->IsUndefined()) {
index = i;
break;
}
}
if (index == kNoBreakPointInfo) {
// No free slot - extend break point info array.
Handle<FixedArray> old_break_points =
Handle<FixedArray>(FixedArray::cast(debug_info->break_points()));
Handle<FixedArray> new_break_points =
isolate->factory()->NewFixedArray(
old_break_points->length() +
DebugInfo::kEstimatedNofBreakPointsInFunction);
debug_info->set_break_points(*new_break_points);
for (int i = 0; i < old_break_points->length(); i++) {
new_break_points->set(i, old_break_points->get(i));
}
index = old_break_points->length();
}
DCHECK(index != kNoBreakPointInfo);
// Allocate new BreakPointInfo object and set the break point.
Handle<BreakPointInfo> new_break_point_info = Handle<BreakPointInfo>::cast(
isolate->factory()->NewStruct(BREAK_POINT_INFO_TYPE));
new_break_point_info->set_code_position(Smi::FromInt(code_position));
new_break_point_info->set_source_position(Smi::FromInt(source_position));
new_break_point_info->
set_statement_position(Smi::FromInt(statement_position));
new_break_point_info->set_break_point_objects(
isolate->heap()->undefined_value());
BreakPointInfo::SetBreakPoint(new_break_point_info, break_point_object);
debug_info->break_points()->set(index, *new_break_point_info);
}
// Get the break point objects for a code position.
Object* DebugInfo::GetBreakPointObjects(int code_position) {
Object* break_point_info = GetBreakPointInfo(code_position);
if (break_point_info->IsUndefined()) {
return GetHeap()->undefined_value();
}
return BreakPointInfo::cast(break_point_info)->break_point_objects();
}
// Get the total number of break points.
int DebugInfo::GetBreakPointCount() {
if (break_points()->IsUndefined()) return 0;
int count = 0;
for (int i = 0; i < break_points()->length(); i++) {
if (!break_points()->get(i)->IsUndefined()) {
BreakPointInfo* break_point_info =
BreakPointInfo::cast(break_points()->get(i));
count += break_point_info->GetBreakPointCount();
}
}
return count;
}
Object* DebugInfo::FindBreakPointInfo(Handle<DebugInfo> debug_info,
Handle<Object> break_point_object) {
Heap* heap = debug_info->GetHeap();
if (debug_info->break_points()->IsUndefined()) return heap->undefined_value();
for (int i = 0; i < debug_info->break_points()->length(); i++) {
if (!debug_info->break_points()->get(i)->IsUndefined()) {
Handle<BreakPointInfo> break_point_info =
Handle<BreakPointInfo>(BreakPointInfo::cast(
debug_info->break_points()->get(i)));
if (BreakPointInfo::HasBreakPointObject(break_point_info,
break_point_object)) {
return *break_point_info;
}
}
}
return heap->undefined_value();
}
// Find the index of the break point info object for the specified code
// position.
int DebugInfo::GetBreakPointInfoIndex(int code_position) {
if (break_points()->IsUndefined()) return kNoBreakPointInfo;
for (int i = 0; i < break_points()->length(); i++) {
if (!break_points()->get(i)->IsUndefined()) {
BreakPointInfo* break_point_info =
BreakPointInfo::cast(break_points()->get(i));
if (break_point_info->code_position()->value() == code_position) {
return i;
}
}
}
return kNoBreakPointInfo;
}
// Remove the specified break point object.
void BreakPointInfo::ClearBreakPoint(Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
Isolate* isolate = break_point_info->GetIsolate();
// If there are no break points just ignore.
if (break_point_info->break_point_objects()->IsUndefined()) return;
// If there is a single break point clear it if it is the same.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
if (break_point_info->break_point_objects() == *break_point_object) {
break_point_info->set_break_point_objects(
isolate->heap()->undefined_value());
}
return;
}
// If there are multiple break points shrink the array
DCHECK(break_point_info->break_point_objects()->IsFixedArray());
Handle<FixedArray> old_array =
Handle<FixedArray>(
FixedArray::cast(break_point_info->break_point_objects()));
Handle<FixedArray> new_array =
isolate->factory()->NewFixedArray(old_array->length() - 1);
int found_count = 0;
for (int i = 0; i < old_array->length(); i++) {
if (old_array->get(i) == *break_point_object) {
DCHECK(found_count == 0);
found_count++;
} else {
new_array->set(i - found_count, old_array->get(i));
}
}
// If the break point was found in the list change it.
if (found_count > 0) break_point_info->set_break_point_objects(*new_array);
}
// Add the specified break point object.
void BreakPointInfo::SetBreakPoint(Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
Isolate* isolate = break_point_info->GetIsolate();
// If there was no break point objects before just set it.
if (break_point_info->break_point_objects()->IsUndefined()) {
break_point_info->set_break_point_objects(*break_point_object);
return;
}
// If the break point object is the same as before just ignore.
if (break_point_info->break_point_objects() == *break_point_object) return;
// If there was one break point object before replace with array.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
Handle<FixedArray> array = isolate->factory()->NewFixedArray(2);
array->set(0, break_point_info->break_point_objects());
array->set(1, *break_point_object);
break_point_info->set_break_point_objects(*array);
return;
}
// If there was more than one break point before extend array.
Handle<FixedArray> old_array =
Handle<FixedArray>(
FixedArray::cast(break_point_info->break_point_objects()));
Handle<FixedArray> new_array =
isolate->factory()->NewFixedArray(old_array->length() + 1);
for (int i = 0; i < old_array->length(); i++) {
// If the break point was there before just ignore.
if (old_array->get(i) == *break_point_object) return;
new_array->set(i, old_array->get(i));
}
// Add the new break point.
new_array->set(old_array->length(), *break_point_object);
break_point_info->set_break_point_objects(*new_array);
}
bool BreakPointInfo::HasBreakPointObject(
Handle<BreakPointInfo> break_point_info,
Handle<Object> break_point_object) {
// No break point.
if (break_point_info->break_point_objects()->IsUndefined()) return false;
// Single break point.
if (!break_point_info->break_point_objects()->IsFixedArray()) {
return break_point_info->break_point_objects() == *break_point_object;
}
// Multiple break points.
FixedArray* array = FixedArray::cast(break_point_info->break_point_objects());
for (int i = 0; i < array->length(); i++) {
if (array->get(i) == *break_point_object) {
return true;
}
}
return false;
}
// Get the number of break points.
int BreakPointInfo::GetBreakPointCount() {
// No break point.
if (break_point_objects()->IsUndefined()) return 0;
// Single break point.
if (!break_point_objects()->IsFixedArray()) return 1;
// Multiple break points.
return FixedArray::cast(break_point_objects())->length();
}
Object* JSDate::GetField(Object* object, Smi* index) {
return JSDate::cast(object)->DoGetField(
static_cast<FieldIndex>(index->value()));
}
Object* JSDate::DoGetField(FieldIndex index) {
DCHECK(index != kDateValue);
DateCache* date_cache = GetIsolate()->date_cache();
if (index < kFirstUncachedField) {
Object* stamp = cache_stamp();
if (stamp != date_cache->stamp() && stamp->IsSmi()) {
// Since the stamp is not NaN, the value is also not NaN.
int64_t local_time_ms =
date_cache->ToLocal(static_cast<int64_t>(value()->Number()));
SetCachedFields(local_time_ms, date_cache);
}
switch (index) {
case kYear: return year();
case kMonth: return month();
case kDay: return day();
case kWeekday: return weekday();
case kHour: return hour();
case kMinute: return min();
case kSecond: return sec();
default: UNREACHABLE();
}
}
if (index >= kFirstUTCField) {
return GetUTCField(index, value()->Number(), date_cache);
}
double time = value()->Number();
if (std::isnan(time)) return GetIsolate()->heap()->nan_value();
int64_t local_time_ms = date_cache->ToLocal(static_cast<int64_t>(time));
int days = DateCache::DaysFromTime(local_time_ms);
if (index == kDays) return Smi::FromInt(days);
int time_in_day_ms = DateCache::TimeInDay(local_time_ms, days);
if (index == kMillisecond) return Smi::FromInt(time_in_day_ms % 1000);
DCHECK(index == kTimeInDay);
return Smi::FromInt(time_in_day_ms);
}
Object* JSDate::GetUTCField(FieldIndex index,
double value,
DateCache* date_cache) {
DCHECK(index >= kFirstUTCField);
if (std::isnan(value)) return GetIsolate()->heap()->nan_value();
int64_t time_ms = static_cast<int64_t>(value);
if (index == kTimezoneOffset) {
return Smi::FromInt(date_cache->TimezoneOffset(time_ms));
}
int days = DateCache::DaysFromTime(time_ms);
if (index == kWeekdayUTC) return Smi::FromInt(date_cache->Weekday(days));
if (index <= kDayUTC) {
int year, month, day;
date_cache->YearMonthDayFromDays(days, &year, &month, &day);
if (index == kYearUTC) return Smi::FromInt(year);
if (index == kMonthUTC) return Smi::FromInt(month);
DCHECK(index == kDayUTC);
return Smi::FromInt(day);
}
int time_in_day_ms = DateCache::TimeInDay(time_ms, days);
switch (index) {
case kHourUTC: return Smi::FromInt(time_in_day_ms / (60 * 60 * 1000));
case kMinuteUTC: return Smi::FromInt((time_in_day_ms / (60 * 1000)) % 60);
case kSecondUTC: return Smi::FromInt((time_in_day_ms / 1000) % 60);
case kMillisecondUTC: return Smi::FromInt(time_in_day_ms % 1000);
case kDaysUTC: return Smi::FromInt(days);
case kTimeInDayUTC: return Smi::FromInt(time_in_day_ms);
default: UNREACHABLE();
}
UNREACHABLE();
return NULL;
}
void JSDate::SetValue(Object* value, bool is_value_nan) {
set_value(value);
if (is_value_nan) {
HeapNumber* nan = GetIsolate()->heap()->nan_value();
set_cache_stamp(nan, SKIP_WRITE_BARRIER);
set_year(nan, SKIP_WRITE_BARRIER);
set_month(nan, SKIP_WRITE_BARRIER);
set_day(nan, SKIP_WRITE_BARRIER);
set_hour(nan, SKIP_WRITE_BARRIER);
set_min(nan, SKIP_WRITE_BARRIER);
set_sec(nan, SKIP_WRITE_BARRIER);
set_weekday(nan, SKIP_WRITE_BARRIER);
} else {
set_cache_stamp(Smi::FromInt(DateCache::kInvalidStamp), SKIP_WRITE_BARRIER);
}
}
void JSDate::SetCachedFields(int64_t local_time_ms, DateCache* date_cache) {
int days = DateCache::DaysFromTime(local_time_ms);
int time_in_day_ms = DateCache::TimeInDay(local_time_ms, days);
int year, month, day;
date_cache->YearMonthDayFromDays(days, &year, &month, &day);
int weekday = date_cache->Weekday(days);
int hour = time_in_day_ms / (60 * 60 * 1000);
int min = (time_in_day_ms / (60 * 1000)) % 60;
int sec = (time_in_day_ms / 1000) % 60;
set_cache_stamp(date_cache->stamp());
set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
}
void JSArrayBuffer::Neuter() {
DCHECK(is_external());
set_backing_store(NULL);
set_byte_length(Smi::FromInt(0));
}
void JSArrayBufferView::NeuterView() {
set_byte_offset(Smi::FromInt(0));
set_byte_length(Smi::FromInt(0));
}
void JSDataView::Neuter() {
NeuterView();
}
void JSTypedArray::Neuter() {
NeuterView();
set_length(Smi::FromInt(0));
set_elements(GetHeap()->EmptyExternalArrayForMap(map()));
}
static ElementsKind FixedToExternalElementsKind(ElementsKind elements_kind) {
switch (elements_kind) {
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
case TYPE##_ELEMENTS: return EXTERNAL_##TYPE##_ELEMENTS;
TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
default:
UNREACHABLE();
return FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND;
}
}
Handle<JSArrayBuffer> JSTypedArray::MaterializeArrayBuffer(
Handle<JSTypedArray> typed_array) {
Handle<Map> map(typed_array->map());
Isolate* isolate = typed_array->GetIsolate();
DCHECK(IsFixedTypedArrayElementsKind(map->elements_kind()));
Handle<Map> new_map = Map::TransitionElementsTo(
map,
FixedToExternalElementsKind(map->elements_kind()));
Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer();
Handle<FixedTypedArrayBase> fixed_typed_array(
FixedTypedArrayBase::cast(typed_array->elements()));
Runtime::SetupArrayBufferAllocatingData(isolate, buffer,
fixed_typed_array->DataSize(), false);
memcpy(buffer->backing_store(),
fixed_typed_array->DataPtr(),
fixed_typed_array->DataSize());
Handle<ExternalArray> new_elements =
isolate->factory()->NewExternalArray(
fixed_typed_array->length(), typed_array->type(),
static_cast<uint8_t*>(buffer->backing_store()));
buffer->set_weak_first_view(*typed_array);
DCHECK(typed_array->weak_next() == isolate->heap()->undefined_value());
typed_array->set_buffer(*buffer);
JSObject::SetMapAndElements(typed_array, new_map, new_elements);
return buffer;
}
Handle<JSArrayBuffer> JSTypedArray::GetBuffer() {
Handle<Object> result(buffer(), GetIsolate());
if (*result != Smi::FromInt(0)) {
DCHECK(IsExternalArrayElementsKind(map()->elements_kind()));
return Handle<JSArrayBuffer>::cast(result);
}
Handle<JSTypedArray> self(this);
return MaterializeArrayBuffer(self);
}
HeapType* PropertyCell::type() {
return static_cast<HeapType*>(type_raw());
}
void PropertyCell::set_type(HeapType* type, WriteBarrierMode ignored) {
DCHECK(IsPropertyCell());
set_type_raw(type, ignored);
}
Handle<HeapType> PropertyCell::UpdatedType(Handle<PropertyCell> cell,
Handle<Object> value) {
Isolate* isolate = cell->GetIsolate();
Handle<HeapType> old_type(cell->type(), isolate);
Handle<HeapType> new_type = HeapType::Constant(value, isolate);
if (new_type->Is(old_type)) return old_type;
cell->dependent_code()->DeoptimizeDependentCodeGroup(
isolate, DependentCode::kPropertyCellChangedGroup);
if (old_type->Is(HeapType::None()) || old_type->Is(HeapType::Undefined())) {
return new_type;
}
return HeapType::Any(isolate);
}
void PropertyCell::SetValueInferType(Handle<PropertyCell> cell,
Handle<Object> value) {
cell->set_value(*value);
if (!HeapType::Any()->Is(cell->type())) {
Handle<HeapType> new_type = UpdatedType(cell, value);
cell->set_type(*new_type);
}
}
// static
void PropertyCell::AddDependentCompilationInfo(Handle<PropertyCell> cell,
CompilationInfo* info) {
Handle<DependentCode> codes =
DependentCode::Insert(handle(cell->dependent_code(), info->isolate()),
DependentCode::kPropertyCellChangedGroup,
info->object_wrapper());
if (*codes != cell->dependent_code()) cell->set_dependent_code(*codes);
info->dependencies(DependentCode::kPropertyCellChangedGroup)->Add(
cell, info->zone());
}
} } // namespace v8::internal