| // Copyright 2014 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/lookup.h" |
| |
| #include "src/bootstrapper.h" |
| #include "src/deoptimizer.h" |
| #include "src/elements.h" |
| #include "src/field-type.h" |
| #include "src/isolate-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // static |
| LookupIterator LookupIterator::PropertyOrElement( |
| Isolate* isolate, Handle<Object> receiver, Handle<Object> key, |
| bool* success, Handle<JSReceiver> holder, Configuration configuration) { |
| uint32_t index = 0; |
| if (key->ToArrayIndex(&index)) { |
| *success = true; |
| return LookupIterator(isolate, receiver, index, holder, configuration); |
| } |
| |
| Handle<Name> name; |
| *success = Object::ToName(isolate, key).ToHandle(&name); |
| if (!*success) { |
| DCHECK(isolate->has_pending_exception()); |
| // Return an unusable dummy. |
| return LookupIterator(receiver, isolate->factory()->empty_string()); |
| } |
| |
| if (name->AsArrayIndex(&index)) { |
| LookupIterator it(isolate, receiver, index, holder, configuration); |
| // Here we try to avoid having to rebuild the string later |
| // by storing it on the indexed LookupIterator. |
| it.name_ = name; |
| return it; |
| } |
| |
| return LookupIterator(receiver, name, holder, configuration); |
| } |
| |
| // static |
| LookupIterator LookupIterator::PropertyOrElement(Isolate* isolate, |
| Handle<Object> receiver, |
| Handle<Object> key, |
| bool* success, |
| Configuration configuration) { |
| // TODO(mslekova): come up with better way to avoid duplication |
| uint32_t index = 0; |
| if (key->ToArrayIndex(&index)) { |
| *success = true; |
| return LookupIterator(isolate, receiver, index, configuration); |
| } |
| |
| Handle<Name> name; |
| *success = Object::ToName(isolate, key).ToHandle(&name); |
| if (!*success) { |
| DCHECK(isolate->has_pending_exception()); |
| // Return an unusable dummy. |
| return LookupIterator(receiver, isolate->factory()->empty_string()); |
| } |
| |
| if (name->AsArrayIndex(&index)) { |
| LookupIterator it(isolate, receiver, index, configuration); |
| // Here we try to avoid having to rebuild the string later |
| // by storing it on the indexed LookupIterator. |
| it.name_ = name; |
| return it; |
| } |
| |
| return LookupIterator(receiver, name, configuration); |
| } |
| |
| // static |
| LookupIterator LookupIterator::ForTransitionHandler( |
| Isolate* isolate, Handle<Object> receiver, Handle<Name> name, |
| Handle<Object> value, MaybeHandle<Object> handler, |
| Handle<Map> transition_map) { |
| if (handler.is_null()) return LookupIterator(receiver, name); |
| |
| PropertyDetails details = PropertyDetails::Empty(); |
| bool has_property; |
| if (transition_map->is_dictionary_map()) { |
| details = PropertyDetails(kData, NONE, PropertyCellType::kNoCell); |
| has_property = false; |
| } else { |
| details = transition_map->GetLastDescriptorDetails(); |
| has_property = true; |
| } |
| LookupIterator it(isolate, receiver, name, transition_map, details, |
| has_property); |
| |
| if (!transition_map->is_dictionary_map()) { |
| int descriptor_number = transition_map->LastAdded(); |
| Handle<Map> new_map = Map::PrepareForDataProperty( |
| transition_map, descriptor_number, kConst, value); |
| // Reload information; this is no-op if nothing changed. |
| it.property_details_ = |
| new_map->instance_descriptors()->GetDetails(descriptor_number); |
| it.transition_ = new_map; |
| } |
| return it; |
| } |
| |
| LookupIterator::LookupIterator(Isolate* isolate, Handle<Object> receiver, |
| Handle<Name> name, Handle<Map> transition_map, |
| PropertyDetails details, bool has_property) |
| : configuration_(DEFAULT), |
| state_(TRANSITION), |
| has_property_(has_property), |
| interceptor_state_(InterceptorState::kUninitialized), |
| property_details_(details), |
| isolate_(isolate), |
| name_(name), |
| transition_(transition_map), |
| receiver_(receiver), |
| initial_holder_(GetRoot(isolate, receiver)), |
| index_(kMaxUInt32), |
| number_(static_cast<uint32_t>(DescriptorArray::kNotFound)) { |
| holder_ = initial_holder_; |
| } |
| |
| template <bool is_element> |
| void LookupIterator::Start() { |
| DisallowHeapAllocation no_gc; |
| |
| has_property_ = false; |
| state_ = NOT_FOUND; |
| holder_ = initial_holder_; |
| |
| JSReceiver* holder = *holder_; |
| Map* map = holder->map(); |
| |
| state_ = LookupInHolder<is_element>(map, holder); |
| if (IsFound()) return; |
| |
| NextInternal<is_element>(map, holder); |
| } |
| |
| template void LookupIterator::Start<true>(); |
| template void LookupIterator::Start<false>(); |
| |
| void LookupIterator::Next() { |
| DCHECK_NE(JSPROXY, state_); |
| DCHECK_NE(TRANSITION, state_); |
| DisallowHeapAllocation no_gc; |
| has_property_ = false; |
| |
| JSReceiver* holder = *holder_; |
| Map* map = holder->map(); |
| |
| if (map->IsSpecialReceiverMap()) { |
| state_ = IsElement() ? LookupInSpecialHolder<true>(map, holder) |
| : LookupInSpecialHolder<false>(map, holder); |
| if (IsFound()) return; |
| } |
| |
| IsElement() ? NextInternal<true>(map, holder) |
| : NextInternal<false>(map, holder); |
| } |
| |
| template <bool is_element> |
| void LookupIterator::NextInternal(Map* map, JSReceiver* holder) { |
| do { |
| JSReceiver* maybe_holder = NextHolder(map); |
| if (maybe_holder == nullptr) { |
| if (interceptor_state_ == InterceptorState::kSkipNonMasking) { |
| RestartLookupForNonMaskingInterceptors<is_element>(); |
| return; |
| } |
| state_ = NOT_FOUND; |
| if (holder != *holder_) holder_ = handle(holder, isolate_); |
| return; |
| } |
| holder = maybe_holder; |
| map = holder->map(); |
| state_ = LookupInHolder<is_element>(map, holder); |
| } while (!IsFound()); |
| |
| holder_ = handle(holder, isolate_); |
| } |
| |
| template <bool is_element> |
| void LookupIterator::RestartInternal(InterceptorState interceptor_state) { |
| interceptor_state_ = interceptor_state; |
| property_details_ = PropertyDetails::Empty(); |
| number_ = static_cast<uint32_t>(DescriptorArray::kNotFound); |
| Start<is_element>(); |
| } |
| |
| template void LookupIterator::RestartInternal<true>(InterceptorState); |
| template void LookupIterator::RestartInternal<false>(InterceptorState); |
| |
| // static |
| Handle<JSReceiver> LookupIterator::GetRootForNonJSReceiver( |
| Isolate* isolate, Handle<Object> receiver, uint32_t index) { |
| // Strings are the only objects with properties (only elements) directly on |
| // the wrapper. Hence we can skip generating the wrapper for all other cases. |
| if (index != kMaxUInt32 && receiver->IsString() && |
| index < static_cast<uint32_t>(String::cast(*receiver)->length())) { |
| // TODO(verwaest): Speed this up. Perhaps use a cached wrapper on the native |
| // context, ensuring that we don't leak it into JS? |
| Handle<JSFunction> constructor = isolate->string_function(); |
| Handle<JSObject> result = isolate->factory()->NewJSObject(constructor); |
| Handle<JSValue>::cast(result)->set_value(*receiver); |
| return result; |
| } |
| auto root = |
| handle(receiver->GetPrototypeChainRootMap(isolate)->prototype(), isolate); |
| if (root->IsNull(isolate)) { |
| unsigned int magic = 0xBBBBBBBB; |
| isolate->PushStackTraceAndDie(magic, *receiver, nullptr, magic); |
| } |
| return Handle<JSReceiver>::cast(root); |
| } |
| |
| |
| Handle<Map> LookupIterator::GetReceiverMap() const { |
| if (receiver_->IsNumber()) return factory()->heap_number_map(); |
| return handle(Handle<HeapObject>::cast(receiver_)->map(), isolate_); |
| } |
| |
| bool LookupIterator::HasAccess() const { |
| DCHECK_EQ(ACCESS_CHECK, state_); |
| return isolate_->MayAccess(handle(isolate_->context()), |
| GetHolder<JSObject>()); |
| } |
| |
| template <bool is_element> |
| void LookupIterator::ReloadPropertyInformation() { |
| state_ = BEFORE_PROPERTY; |
| interceptor_state_ = InterceptorState::kUninitialized; |
| state_ = LookupInHolder<is_element>(holder_->map(), *holder_); |
| DCHECK(IsFound() || !holder_->HasFastProperties()); |
| } |
| |
| namespace { |
| bool IsTypedArrayFunctionInAnyContext(Isolate* isolate, JSReceiver* holder) { |
| static uint32_t context_slots[] = { |
| #define TYPED_ARRAY_CONTEXT_SLOTS(Type, type, TYPE, ctype, size) \ |
| Context::TYPE##_ARRAY_FUN_INDEX, |
| |
| TYPED_ARRAYS(TYPED_ARRAY_CONTEXT_SLOTS) |
| #undef TYPED_ARRAY_CONTEXT_SLOTS |
| }; |
| |
| if (!holder->IsJSFunction()) return false; |
| |
| return std::any_of( |
| std::begin(context_slots), std::end(context_slots), |
| [=](uint32_t slot) { return isolate->IsInAnyContext(holder, slot); }); |
| } |
| } // namespace |
| |
| void LookupIterator::InternalUpdateProtector() { |
| if (isolate_->bootstrapper()->IsActive()) return; |
| |
| if (*name_ == heap()->constructor_string()) { |
| if (!isolate_->IsArraySpeciesLookupChainIntact()) return; |
| // Setting the constructor property could change an instance's @@species |
| if (holder_->IsJSArray() || holder_->IsJSTypedArray()) { |
| isolate_->CountUsage( |
| v8::Isolate::UseCounterFeature::kArrayInstanceConstructorModified); |
| isolate_->InvalidateArraySpeciesProtector(); |
| } else if (holder_->map()->is_prototype_map()) { |
| DisallowHeapAllocation no_gc; |
| // Setting the constructor of Array.prototype or %TypedArray%.prototype of |
| // any realm also needs to invalidate the species protector. |
| // For typed arrays, we check a prototype of this holder since TypedArrays |
| // have different prototypes for each type, and their parent prototype is |
| // pointing the same TYPED_ARRAY_PROTOTYPE. |
| if (isolate_->IsInAnyContext(*holder_, |
| Context::INITIAL_ARRAY_PROTOTYPE_INDEX) || |
| isolate_->IsInAnyContext(holder_->map()->prototype(), |
| Context::TYPED_ARRAY_PROTOTYPE_INDEX)) { |
| isolate_->CountUsage(v8::Isolate::UseCounterFeature:: |
| kArrayPrototypeConstructorModified); |
| isolate_->InvalidateArraySpeciesProtector(); |
| } |
| } |
| } else if (*name_ == heap()->species_symbol()) { |
| if (!isolate_->IsArraySpeciesLookupChainIntact()) return; |
| // Setting the Symbol.species property of any Array or TypedArray |
| // constructor invalidates the species protector |
| if (isolate_->IsInAnyContext(*holder_, Context::ARRAY_FUNCTION_INDEX) || |
| IsTypedArrayFunctionInAnyContext(isolate_, *holder_)) { |
| isolate_->CountUsage( |
| v8::Isolate::UseCounterFeature::kArraySpeciesModified); |
| isolate_->InvalidateArraySpeciesProtector(); |
| } |
| } else if (*name_ == heap()->is_concat_spreadable_symbol()) { |
| if (!isolate_->IsIsConcatSpreadableLookupChainIntact()) return; |
| isolate_->InvalidateIsConcatSpreadableProtector(); |
| } else if (*name_ == heap()->iterator_symbol()) { |
| if (!isolate_->IsArrayIteratorLookupChainIntact()) return; |
| if (holder_->IsJSArray()) { |
| isolate_->InvalidateArrayIteratorProtector(); |
| } |
| } |
| } |
| |
| void LookupIterator::PrepareForDataProperty(Handle<Object> value) { |
| DCHECK(state_ == DATA || state_ == ACCESSOR); |
| DCHECK(HolderIsReceiverOrHiddenPrototype()); |
| |
| Handle<JSObject> holder = GetHolder<JSObject>(); |
| |
| if (IsElement()) { |
| ElementsKind kind = holder->GetElementsKind(); |
| ElementsKind to = value->OptimalElementsKind(); |
| if (IsHoleyOrDictionaryElementsKind(kind)) to = GetHoleyElementsKind(to); |
| to = GetMoreGeneralElementsKind(kind, to); |
| |
| if (kind != to) { |
| JSObject::TransitionElementsKind(holder, to); |
| } |
| |
| // Copy the backing store if it is copy-on-write. |
| if (IsSmiOrObjectElementsKind(to)) { |
| JSObject::EnsureWritableFastElements(holder); |
| } |
| return; |
| } |
| |
| if (holder->IsJSGlobalObject()) { |
| Handle<GlobalDictionary> dictionary( |
| JSGlobalObject::cast(*holder)->global_dictionary()); |
| Handle<PropertyCell> cell(dictionary->CellAt(dictionary_entry())); |
| property_details_ = cell->property_details(); |
| PropertyCell::PrepareForValue(dictionary, dictionary_entry(), value, |
| property_details_); |
| return; |
| } |
| if (!holder->HasFastProperties()) return; |
| |
| PropertyConstness new_constness = kConst; |
| if (FLAG_track_constant_fields) { |
| if (constness() == kConst) { |
| DCHECK_EQ(kData, property_details_.kind()); |
| // Check that current value matches new value otherwise we should make |
| // the property mutable. |
| if (!IsConstFieldValueEqualTo(*value)) new_constness = kMutable; |
| } |
| } else { |
| new_constness = kMutable; |
| } |
| |
| Handle<Map> old_map(holder->map(), isolate_); |
| Handle<Map> new_map = Map::PrepareForDataProperty( |
| old_map, descriptor_number(), new_constness, value); |
| |
| if (old_map.is_identical_to(new_map)) { |
| // Update the property details if the representation was None. |
| if (constness() != new_constness || representation().IsNone()) { |
| property_details_ = |
| new_map->instance_descriptors()->GetDetails(descriptor_number()); |
| } |
| return; |
| } |
| |
| JSObject::MigrateToMap(holder, new_map); |
| ReloadPropertyInformation<false>(); |
| } |
| |
| |
| void LookupIterator::ReconfigureDataProperty(Handle<Object> value, |
| PropertyAttributes attributes) { |
| DCHECK(state_ == DATA || state_ == ACCESSOR); |
| DCHECK(HolderIsReceiverOrHiddenPrototype()); |
| Handle<JSObject> holder = GetHolder<JSObject>(); |
| if (IsElement()) { |
| DCHECK(!holder->HasFixedTypedArrayElements()); |
| DCHECK(attributes != NONE || !holder->HasFastElements()); |
| Handle<FixedArrayBase> elements(holder->elements()); |
| holder->GetElementsAccessor()->Reconfigure(holder, elements, number_, value, |
| attributes); |
| ReloadPropertyInformation<true>(); |
| } else if (holder->HasFastProperties()) { |
| Handle<Map> old_map(holder->map(), isolate_); |
| Handle<Map> new_map = Map::ReconfigureExistingProperty( |
| old_map, descriptor_number(), i::kData, attributes); |
| // Force mutable to avoid changing constant value by reconfiguring |
| // kData -> kAccessor -> kData. |
| new_map = Map::PrepareForDataProperty(new_map, descriptor_number(), |
| kMutable, value); |
| JSObject::MigrateToMap(holder, new_map); |
| ReloadPropertyInformation<false>(); |
| } |
| |
| if (!IsElement() && !holder->HasFastProperties()) { |
| PropertyDetails details(kData, attributes, PropertyCellType::kMutable); |
| if (holder->IsJSGlobalObject()) { |
| Handle<GlobalDictionary> dictionary( |
| JSGlobalObject::cast(*holder)->global_dictionary()); |
| |
| Handle<PropertyCell> cell = PropertyCell::PrepareForValue( |
| dictionary, dictionary_entry(), value, details); |
| cell->set_value(*value); |
| property_details_ = cell->property_details(); |
| } else { |
| Handle<NameDictionary> dictionary(holder->property_dictionary()); |
| PropertyDetails original_details = |
| dictionary->DetailsAt(dictionary_entry()); |
| int enumeration_index = original_details.dictionary_index(); |
| DCHECK_GT(enumeration_index, 0); |
| details = details.set_index(enumeration_index); |
| dictionary->SetEntry(dictionary_entry(), *name(), *value, details); |
| property_details_ = details; |
| } |
| state_ = DATA; |
| } |
| |
| WriteDataValue(value, true); |
| |
| #if VERIFY_HEAP |
| if (FLAG_verify_heap) { |
| holder->JSObjectVerify(); |
| } |
| #endif |
| } |
| |
| // Can only be called when the receiver is a JSObject. JSProxy has to be handled |
| // via a trap. Adding properties to primitive values is not observable. |
| // Returns true if a new transition has been created, or false if an existing |
| // transition was followed. |
| bool LookupIterator::PrepareTransitionToDataProperty( |
| Handle<JSObject> receiver, Handle<Object> value, |
| PropertyAttributes attributes, Object::StoreFromKeyed store_mode) { |
| DCHECK(receiver.is_identical_to(GetStoreTarget())); |
| if (state_ == TRANSITION) return false; |
| |
| if (!IsElement() && name()->IsPrivate()) { |
| attributes = static_cast<PropertyAttributes>(attributes | DONT_ENUM); |
| } |
| |
| DCHECK(state_ != LookupIterator::ACCESSOR || |
| (GetAccessors()->IsAccessorInfo() && |
| AccessorInfo::cast(*GetAccessors())->is_special_data_property())); |
| DCHECK_NE(INTEGER_INDEXED_EXOTIC, state_); |
| #if !defined(COBALT_ARRAY_BUFFER_COLLISION_WORKAROUND) |
| DCHECK(state_ == NOT_FOUND || !HolderIsReceiverOrHiddenPrototype()); |
| #endif |
| |
| Handle<Map> map(receiver->map(), isolate_); |
| |
| // Dictionary maps can always have additional data properties. |
| if (map->is_dictionary_map()) { |
| state_ = TRANSITION; |
| if (map->IsJSGlobalObjectMap()) { |
| // Install a property cell. |
| Handle<JSGlobalObject> global = Handle<JSGlobalObject>::cast(receiver); |
| int entry; |
| Handle<PropertyCell> cell = JSGlobalObject::EnsureEmptyPropertyCell( |
| global, name(), PropertyCellType::kUninitialized, &entry); |
| Handle<GlobalDictionary> dictionary(global->global_dictionary(), |
| isolate_); |
| #if !defined(COBALT_ARRAY_BUFFER_COLLISION_WORKAROUND) |
| DCHECK(cell->value()->IsTheHole(isolate_)); |
| #endif |
| DCHECK(!value->IsTheHole(isolate_)); |
| transition_ = cell; |
| // Assign an enumeration index to the property and update |
| // SetNextEnumerationIndex. |
| int index = dictionary->NextEnumerationIndex(); |
| dictionary->SetNextEnumerationIndex(index + 1); |
| property_details_ = PropertyDetails( |
| kData, attributes, PropertyCellType::kUninitialized, index); |
| PropertyCellType new_type = |
| PropertyCell::UpdatedType(cell, value, property_details_); |
| property_details_ = property_details_.set_cell_type(new_type); |
| cell->set_property_details(property_details_); |
| number_ = entry; |
| has_property_ = true; |
| } else { |
| // Don't set enumeration index (it will be set during value store). |
| property_details_ = |
| PropertyDetails(kData, attributes, PropertyCellType::kNoCell); |
| transition_ = map; |
| } |
| return false; |
| } |
| |
| bool created_new_map; |
| Handle<Map> transition = Map::TransitionToDataProperty( |
| map, name_, value, attributes, kDefaultFieldConstness, store_mode, |
| &created_new_map); |
| state_ = TRANSITION; |
| transition_ = transition; |
| |
| if (transition->is_dictionary_map()) { |
| // Don't set enumeration index (it will be set during value store). |
| property_details_ = |
| PropertyDetails(kData, attributes, PropertyCellType::kNoCell); |
| } else { |
| property_details_ = transition->GetLastDescriptorDetails(); |
| has_property_ = true; |
| } |
| return created_new_map; |
| } |
| |
| void LookupIterator::ApplyTransitionToDataProperty(Handle<JSObject> receiver) { |
| DCHECK_EQ(TRANSITION, state_); |
| |
| DCHECK(receiver.is_identical_to(GetStoreTarget())); |
| holder_ = receiver; |
| if (receiver->IsJSGlobalObject()) { |
| JSObject::InvalidatePrototypeChains(receiver->map()); |
| state_ = DATA; |
| return; |
| } |
| Handle<Map> transition = transition_map(); |
| bool simple_transition = transition->GetBackPointer() == receiver->map(); |
| JSObject::MigrateToMap(receiver, transition); |
| |
| if (simple_transition) { |
| int number = transition->LastAdded(); |
| number_ = static_cast<uint32_t>(number); |
| property_details_ = transition->GetLastDescriptorDetails(); |
| state_ = DATA; |
| } else if (receiver->map()->is_dictionary_map()) { |
| Handle<NameDictionary> dictionary(receiver->property_dictionary(), |
| isolate_); |
| int entry; |
| if (receiver->map()->is_prototype_map()) { |
| JSObject::InvalidatePrototypeChains(receiver->map()); |
| } |
| dictionary = NameDictionary::Add(dictionary, name(), |
| isolate_->factory()->uninitialized_value(), |
| property_details_, &entry); |
| receiver->SetProperties(*dictionary); |
| // Reload details containing proper enumeration index value. |
| property_details_ = dictionary->DetailsAt(entry); |
| number_ = entry; |
| has_property_ = true; |
| state_ = DATA; |
| |
| } else { |
| ReloadPropertyInformation<false>(); |
| } |
| } |
| |
| |
| void LookupIterator::Delete() { |
| Handle<JSReceiver> holder = Handle<JSReceiver>::cast(holder_); |
| if (IsElement()) { |
| Handle<JSObject> object = Handle<JSObject>::cast(holder); |
| ElementsAccessor* accessor = object->GetElementsAccessor(); |
| accessor->Delete(object, number_); |
| } else { |
| bool is_prototype_map = holder->map()->is_prototype_map(); |
| RuntimeCallTimerScope stats_scope( |
| isolate_, is_prototype_map |
| ? RuntimeCallCounterId::kPrototypeObject_DeleteProperty |
| : RuntimeCallCounterId::kObject_DeleteProperty); |
| |
| PropertyNormalizationMode mode = |
| is_prototype_map ? KEEP_INOBJECT_PROPERTIES : CLEAR_INOBJECT_PROPERTIES; |
| |
| if (holder->HasFastProperties()) { |
| JSObject::NormalizeProperties(Handle<JSObject>::cast(holder), mode, 0, |
| "DeletingProperty"); |
| ReloadPropertyInformation<false>(); |
| } |
| JSReceiver::DeleteNormalizedProperty(holder, number_); |
| if (holder->IsJSObject()) { |
| JSObject::ReoptimizeIfPrototype(Handle<JSObject>::cast(holder)); |
| } |
| } |
| state_ = NOT_FOUND; |
| } |
| |
| void LookupIterator::TransitionToAccessorProperty( |
| Handle<Object> getter, Handle<Object> setter, |
| PropertyAttributes attributes) { |
| DCHECK(!getter->IsNull(isolate_) || !setter->IsNull(isolate_)); |
| // Can only be called when the receiver is a JSObject. JSProxy has to be |
| // handled via a trap. Adding properties to primitive values is not |
| // observable. |
| Handle<JSObject> receiver = GetStoreTarget(); |
| if (!IsElement() && name()->IsPrivate()) { |
| attributes = static_cast<PropertyAttributes>(attributes | DONT_ENUM); |
| } |
| |
| if (!IsElement() && !receiver->map()->is_dictionary_map()) { |
| Handle<Map> old_map(receiver->map(), isolate_); |
| |
| if (!holder_.is_identical_to(receiver)) { |
| holder_ = receiver; |
| state_ = NOT_FOUND; |
| } else if (state_ == INTERCEPTOR) { |
| LookupInRegularHolder<false>(*old_map, *holder_); |
| } |
| int descriptor = |
| IsFound() ? static_cast<int>(number_) : DescriptorArray::kNotFound; |
| |
| Handle<Map> new_map = Map::TransitionToAccessorProperty( |
| isolate_, old_map, name_, descriptor, getter, setter, attributes); |
| bool simple_transition = new_map->GetBackPointer() == receiver->map(); |
| JSObject::MigrateToMap(receiver, new_map); |
| |
| if (simple_transition) { |
| int number = new_map->LastAdded(); |
| number_ = static_cast<uint32_t>(number); |
| property_details_ = new_map->GetLastDescriptorDetails(); |
| state_ = ACCESSOR; |
| return; |
| } |
| |
| ReloadPropertyInformation<false>(); |
| if (!new_map->is_dictionary_map()) return; |
| } |
| |
| Handle<AccessorPair> pair; |
| if (state() == ACCESSOR && GetAccessors()->IsAccessorPair()) { |
| pair = Handle<AccessorPair>::cast(GetAccessors()); |
| // If the component and attributes are identical, nothing has to be done. |
| if (pair->Equals(*getter, *setter)) { |
| if (property_details().attributes() == attributes) { |
| if (!IsElement()) JSObject::ReoptimizeIfPrototype(receiver); |
| return; |
| } |
| } else { |
| pair = AccessorPair::Copy(pair); |
| pair->SetComponents(*getter, *setter); |
| } |
| } else { |
| pair = factory()->NewAccessorPair(); |
| pair->SetComponents(*getter, *setter); |
| } |
| |
| TransitionToAccessorPair(pair, attributes); |
| |
| #if VERIFY_HEAP |
| if (FLAG_verify_heap) { |
| receiver->JSObjectVerify(); |
| } |
| #endif |
| } |
| |
| |
| void LookupIterator::TransitionToAccessorPair(Handle<Object> pair, |
| PropertyAttributes attributes) { |
| Handle<JSObject> receiver = GetStoreTarget(); |
| holder_ = receiver; |
| |
| PropertyDetails details(kAccessor, attributes, PropertyCellType::kMutable); |
| |
| if (IsElement()) { |
| // TODO(verwaest): Move code into the element accessor. |
| isolate_->CountUsage(v8::Isolate::kIndexAccessor); |
| Handle<NumberDictionary> dictionary = JSObject::NormalizeElements(receiver); |
| |
| dictionary = |
| NumberDictionary::Set(dictionary, index_, pair, receiver, details); |
| receiver->RequireSlowElements(*dictionary); |
| |
| if (receiver->HasSlowArgumentsElements()) { |
| FixedArray* parameter_map = FixedArray::cast(receiver->elements()); |
| uint32_t length = parameter_map->length() - 2; |
| if (number_ < length) { |
| parameter_map->set(number_ + 2, heap()->the_hole_value()); |
| } |
| FixedArray::cast(receiver->elements())->set(1, *dictionary); |
| } else { |
| receiver->set_elements(*dictionary); |
| } |
| |
| ReloadPropertyInformation<true>(); |
| } else { |
| PropertyNormalizationMode mode = CLEAR_INOBJECT_PROPERTIES; |
| if (receiver->map()->is_prototype_map()) { |
| JSObject::InvalidatePrototypeChains(receiver->map()); |
| mode = KEEP_INOBJECT_PROPERTIES; |
| } |
| |
| // Normalize object to make this operation simple. |
| JSObject::NormalizeProperties(receiver, mode, 0, |
| "TransitionToAccessorPair"); |
| |
| JSObject::SetNormalizedProperty(receiver, name_, pair, details); |
| JSObject::ReoptimizeIfPrototype(receiver); |
| |
| ReloadPropertyInformation<false>(); |
| } |
| } |
| |
| bool LookupIterator::HolderIsReceiver() const { |
| DCHECK(has_property_ || state_ == INTERCEPTOR || state_ == JSPROXY); |
| // Optimization that only works if configuration_ is not mutable. |
| if (!check_prototype_chain()) return true; |
| return *receiver_ == *holder_; |
| } |
| |
| bool LookupIterator::HolderIsReceiverOrHiddenPrototype() const { |
| DCHECK(has_property_ || state_ == INTERCEPTOR || state_ == JSPROXY); |
| // Optimization that only works if configuration_ is not mutable. |
| if (!check_prototype_chain()) return true; |
| DisallowHeapAllocation no_gc; |
| if (*receiver_ == *holder_) return true; |
| if (!receiver_->IsJSReceiver()) return false; |
| JSReceiver* current = JSReceiver::cast(*receiver_); |
| JSReceiver* object = *holder_; |
| if (!current->map()->has_hidden_prototype()) return false; |
| // JSProxy do not occur as hidden prototypes. |
| if (object->IsJSProxy()) return false; |
| PrototypeIterator iter(isolate(), current, kStartAtPrototype, |
| PrototypeIterator::END_AT_NON_HIDDEN); |
| while (!iter.IsAtEnd()) { |
| if (iter.GetCurrent<JSReceiver>() == object) return true; |
| iter.Advance(); |
| } |
| return false; |
| } |
| |
| |
| Handle<Object> LookupIterator::FetchValue() const { |
| Object* result = nullptr; |
| if (IsElement()) { |
| Handle<JSObject> holder = GetHolder<JSObject>(); |
| ElementsAccessor* accessor = holder->GetElementsAccessor(); |
| return accessor->Get(holder, number_); |
| } else if (holder_->IsJSGlobalObject()) { |
| Handle<JSGlobalObject> holder = GetHolder<JSGlobalObject>(); |
| result = holder->global_dictionary()->ValueAt(number_); |
| } else if (!holder_->HasFastProperties()) { |
| result = holder_->property_dictionary()->ValueAt(number_); |
| } else if (property_details_.location() == kField) { |
| DCHECK_EQ(kData, property_details_.kind()); |
| Handle<JSObject> holder = GetHolder<JSObject>(); |
| FieldIndex field_index = FieldIndex::ForDescriptor(holder->map(), number_); |
| return JSObject::FastPropertyAt(holder, property_details_.representation(), |
| field_index); |
| } else { |
| result = holder_->map()->instance_descriptors()->GetValue(number_); |
| } |
| return handle(result, isolate_); |
| } |
| |
| bool LookupIterator::IsConstFieldValueEqualTo(Object* value) const { |
| DCHECK(!IsElement()); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kField, property_details_.location()); |
| DCHECK_EQ(kConst, property_details_.constness()); |
| Handle<JSObject> holder = GetHolder<JSObject>(); |
| FieldIndex field_index = FieldIndex::ForDescriptor(holder->map(), number_); |
| if (property_details_.representation().IsDouble()) { |
| if (!value->IsNumber()) return false; |
| uint64_t bits; |
| if (holder->IsUnboxedDoubleField(field_index)) { |
| bits = holder->RawFastDoublePropertyAsBitsAt(field_index); |
| } else { |
| Object* current_value = holder->RawFastPropertyAt(field_index); |
| DCHECK(current_value->IsMutableHeapNumber()); |
| bits = HeapNumber::cast(current_value)->value_as_bits(); |
| } |
| // Use bit representation of double to to check for hole double, since |
| // manipulating the signaling NaN used for the hole in C++, e.g. with |
| // bit_cast or value(), will change its value on ia32 (the x87 stack is |
| // used to return values and stores to the stack silently clear the |
| // signalling bit). |
| if (bits == kHoleNanInt64) { |
| // Uninitialized double field. |
| return true; |
| } |
| return bit_cast<double>(bits) == value->Number(); |
| } else { |
| Object* current_value = holder->RawFastPropertyAt(field_index); |
| return current_value->IsUninitialized(isolate()) || current_value == value; |
| } |
| } |
| |
| int LookupIterator::GetFieldDescriptorIndex() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kField, property_details_.location()); |
| DCHECK_EQ(kData, property_details_.kind()); |
| return descriptor_number(); |
| } |
| |
| int LookupIterator::GetAccessorIndex() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kDescriptor, property_details_.location()); |
| DCHECK_EQ(kAccessor, property_details_.kind()); |
| return descriptor_number(); |
| } |
| |
| |
| int LookupIterator::GetConstantIndex() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kDescriptor, property_details_.location()); |
| DCHECK_EQ(kData, property_details_.kind()); |
| DCHECK(!FLAG_track_constant_fields); |
| DCHECK(!IsElement()); |
| return descriptor_number(); |
| } |
| |
| Handle<Map> LookupIterator::GetFieldOwnerMap() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kField, property_details_.location()); |
| DCHECK(!IsElement()); |
| Map* holder_map = holder_->map(); |
| return handle(holder_map->FindFieldOwner(descriptor_number()), isolate_); |
| } |
| |
| FieldIndex LookupIterator::GetFieldIndex() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kField, property_details_.location()); |
| DCHECK(!IsElement()); |
| return FieldIndex::ForDescriptor(holder_->map(), descriptor_number()); |
| } |
| |
| Handle<FieldType> LookupIterator::GetFieldType() const { |
| DCHECK(has_property_); |
| DCHECK(holder_->HasFastProperties()); |
| DCHECK_EQ(kField, property_details_.location()); |
| return handle( |
| holder_->map()->instance_descriptors()->GetFieldType(descriptor_number()), |
| isolate_); |
| } |
| |
| |
| Handle<PropertyCell> LookupIterator::GetPropertyCell() const { |
| DCHECK(!IsElement()); |
| Handle<JSGlobalObject> holder = GetHolder<JSGlobalObject>(); |
| return handle(holder->global_dictionary()->CellAt(dictionary_entry()), |
| isolate_); |
| } |
| |
| |
| Handle<Object> LookupIterator::GetAccessors() const { |
| DCHECK_EQ(ACCESSOR, state_); |
| return FetchValue(); |
| } |
| |
| |
| Handle<Object> LookupIterator::GetDataValue() const { |
| DCHECK_EQ(DATA, state_); |
| Handle<Object> value = FetchValue(); |
| return value; |
| } |
| |
| void LookupIterator::WriteDataValue(Handle<Object> value, |
| bool initializing_store) { |
| DCHECK_EQ(DATA, state_); |
| Handle<JSReceiver> holder = GetHolder<JSReceiver>(); |
| if (IsElement()) { |
| Handle<JSObject> object = Handle<JSObject>::cast(holder); |
| ElementsAccessor* accessor = object->GetElementsAccessor(); |
| accessor->Set(object, number_, *value); |
| } else if (holder->HasFastProperties()) { |
| if (property_details_.location() == kField) { |
| // Check that in case of kConst field the existing value is equal to |
| // |value|. |
| DCHECK_IMPLIES( |
| !initializing_store && property_details_.constness() == kConst, |
| IsConstFieldValueEqualTo(*value)); |
| JSObject::cast(*holder)->WriteToField(descriptor_number(), |
| property_details_, *value); |
| } else { |
| DCHECK_EQ(kDescriptor, property_details_.location()); |
| DCHECK_EQ(kConst, property_details_.constness()); |
| } |
| } else if (holder->IsJSGlobalObject()) { |
| GlobalDictionary* dictionary = |
| JSGlobalObject::cast(*holder)->global_dictionary(); |
| dictionary->CellAt(dictionary_entry())->set_value(*value); |
| } else { |
| NameDictionary* dictionary = holder->property_dictionary(); |
| dictionary->ValueAtPut(dictionary_entry(), *value); |
| } |
| } |
| |
| template <bool is_element> |
| bool LookupIterator::SkipInterceptor(JSObject* holder) { |
| auto info = GetInterceptor<is_element>(holder); |
| if (!is_element && name_->IsSymbol() && !info->can_intercept_symbols()) { |
| return true; |
| } |
| if (info->non_masking()) { |
| switch (interceptor_state_) { |
| case InterceptorState::kUninitialized: |
| interceptor_state_ = InterceptorState::kSkipNonMasking; |
| // Fall through. |
| case InterceptorState::kSkipNonMasking: |
| return true; |
| case InterceptorState::kProcessNonMasking: |
| return false; |
| } |
| } |
| return interceptor_state_ == InterceptorState::kProcessNonMasking; |
| } |
| |
| JSReceiver* LookupIterator::NextHolder(Map* map) { |
| DisallowHeapAllocation no_gc; |
| if (map->prototype() == heap()->null_value()) return nullptr; |
| if (!check_prototype_chain() && !map->has_hidden_prototype()) return nullptr; |
| return JSReceiver::cast(map->prototype()); |
| } |
| |
| LookupIterator::State LookupIterator::NotFound(JSReceiver* const holder) const { |
| DCHECK(!IsElement()); |
| if (!holder->IsJSTypedArray() || !name_->IsString()) return NOT_FOUND; |
| |
| Handle<String> name_string = Handle<String>::cast(name_); |
| if (name_string->length() == 0) return NOT_FOUND; |
| |
| return IsSpecialIndex(isolate_->unicode_cache(), *name_string) |
| ? INTEGER_INDEXED_EXOTIC |
| : NOT_FOUND; |
| } |
| |
| namespace { |
| |
| template <bool is_element> |
| bool HasInterceptor(Map* map) { |
| return is_element ? map->has_indexed_interceptor() |
| : map->has_named_interceptor(); |
| } |
| |
| } // namespace |
| |
| template <bool is_element> |
| LookupIterator::State LookupIterator::LookupInSpecialHolder( |
| Map* const map, JSReceiver* const holder) { |
| STATIC_ASSERT(INTERCEPTOR == BEFORE_PROPERTY); |
| switch (state_) { |
| case NOT_FOUND: |
| if (map->IsJSProxyMap()) { |
| if (is_element || !name_->IsPrivate()) return JSPROXY; |
| } |
| if (map->is_access_check_needed()) { |
| if (is_element || !name_->IsPrivate()) return ACCESS_CHECK; |
| } |
| // Fall through. |
| case ACCESS_CHECK: |
| if (check_interceptor() && HasInterceptor<is_element>(map) && |
| !SkipInterceptor<is_element>(JSObject::cast(holder))) { |
| if (is_element || !name_->IsPrivate()) return INTERCEPTOR; |
| } |
| // Fall through. |
| case INTERCEPTOR: |
| if (!is_element && map->IsJSGlobalObjectMap()) { |
| GlobalDictionary* dict = |
| JSGlobalObject::cast(holder)->global_dictionary(); |
| int number = dict->FindEntry(name_); |
| if (number == GlobalDictionary::kNotFound) return NOT_FOUND; |
| number_ = static_cast<uint32_t>(number); |
| PropertyCell* cell = dict->CellAt(number_); |
| if (cell->value()->IsTheHole(isolate_)) return NOT_FOUND; |
| property_details_ = cell->property_details(); |
| has_property_ = true; |
| switch (property_details_.kind()) { |
| case v8::internal::kData: |
| return DATA; |
| case v8::internal::kAccessor: |
| return ACCESSOR; |
| } |
| } |
| return LookupInRegularHolder<is_element>(map, holder); |
| case ACCESSOR: |
| case DATA: |
| return NOT_FOUND; |
| case INTEGER_INDEXED_EXOTIC: |
| case JSPROXY: |
| case TRANSITION: |
| UNREACHABLE(); |
| } |
| UNREACHABLE(); |
| } |
| |
| template <bool is_element> |
| LookupIterator::State LookupIterator::LookupInRegularHolder( |
| Map* const map, JSReceiver* const holder) { |
| DisallowHeapAllocation no_gc; |
| if (interceptor_state_ == InterceptorState::kProcessNonMasking) { |
| return NOT_FOUND; |
| } |
| |
| if (is_element) { |
| JSObject* js_object = JSObject::cast(holder); |
| ElementsAccessor* accessor = js_object->GetElementsAccessor(); |
| FixedArrayBase* backing_store = js_object->elements(); |
| number_ = |
| accessor->GetEntryForIndex(isolate_, js_object, backing_store, index_); |
| if (number_ == kMaxUInt32) { |
| return holder->IsJSTypedArray() ? INTEGER_INDEXED_EXOTIC : NOT_FOUND; |
| } |
| property_details_ = accessor->GetDetails(js_object, number_); |
| } else if (!map->is_dictionary_map()) { |
| DescriptorArray* descriptors = map->instance_descriptors(); |
| int number = descriptors->SearchWithCache(isolate_, *name_, map); |
| if (number == DescriptorArray::kNotFound) return NotFound(holder); |
| number_ = static_cast<uint32_t>(number); |
| property_details_ = descriptors->GetDetails(number_); |
| } else { |
| NameDictionary* dict = holder->property_dictionary(); |
| int number = dict->FindEntry(name_); |
| if (number == NameDictionary::kNotFound) return NotFound(holder); |
| number_ = static_cast<uint32_t>(number); |
| property_details_ = dict->DetailsAt(number_); |
| } |
| has_property_ = true; |
| switch (property_details_.kind()) { |
| case v8::internal::kData: |
| return DATA; |
| case v8::internal::kAccessor: |
| return ACCESSOR; |
| } |
| |
| UNREACHABLE(); |
| } |
| |
| Handle<InterceptorInfo> LookupIterator::GetInterceptorForFailedAccessCheck() |
| const { |
| DCHECK_EQ(ACCESS_CHECK, state_); |
| DisallowHeapAllocation no_gc; |
| AccessCheckInfo* access_check_info = |
| AccessCheckInfo::Get(isolate_, Handle<JSObject>::cast(holder_)); |
| if (access_check_info) { |
| Object* interceptor = IsElement() ? access_check_info->indexed_interceptor() |
| : access_check_info->named_interceptor(); |
| if (interceptor) { |
| return handle(InterceptorInfo::cast(interceptor), isolate_); |
| } |
| } |
| return Handle<InterceptorInfo>(); |
| } |
| |
| bool LookupIterator::TryLookupCachedProperty() { |
| return state() == LookupIterator::ACCESSOR && |
| GetAccessors()->IsAccessorPair() && LookupCachedProperty(); |
| } |
| |
| bool LookupIterator::LookupCachedProperty() { |
| DCHECK_EQ(state(), LookupIterator::ACCESSOR); |
| DCHECK(GetAccessors()->IsAccessorPair()); |
| |
| AccessorPair* accessor_pair = AccessorPair::cast(*GetAccessors()); |
| Handle<Object> getter(accessor_pair->getter(), isolate()); |
| MaybeHandle<Name> maybe_name = |
| FunctionTemplateInfo::TryGetCachedPropertyName(isolate(), getter); |
| if (maybe_name.is_null()) return false; |
| |
| // We have found a cached property! Modify the iterator accordingly. |
| name_ = maybe_name.ToHandleChecked(); |
| Restart(); |
| CHECK_EQ(state(), LookupIterator::DATA); |
| return true; |
| } |
| |
| } // namespace internal |
| } // namespace v8 |
