| // Copyright 2016 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/ic/keyed-store-generic.h" |
| |
| #include "src/codegen/code-factory.h" |
| #include "src/codegen/code-stub-assembler.h" |
| #include "src/codegen/interface-descriptors.h" |
| #include "src/execution/isolate.h" |
| #include "src/ic/accessor-assembler.h" |
| #include "src/objects/contexts.h" |
| #include "src/objects/feedback-vector.h" |
| #include "src/objects/objects-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| using Node = compiler::Node; |
| template <class T> |
| using TNode = compiler::TNode<T>; |
| |
| enum class StoreMode { kOrdinary, kInLiteral }; |
| |
| class KeyedStoreGenericAssembler : public AccessorAssembler { |
| public: |
| explicit KeyedStoreGenericAssembler(compiler::CodeAssemblerState* state, |
| StoreMode mode) |
| : AccessorAssembler(state), mode_(mode) {} |
| |
| void KeyedStoreGeneric(); |
| |
| void StoreIC_Uninitialized(); |
| |
| // Generates code for [[Set]] operation, the |unique_name| is supposed to be |
| // unique otherwise this code will always go to runtime. |
| void SetProperty(TNode<Context> context, TNode<JSReceiver> receiver, |
| TNode<BoolT> is_simple_receiver, TNode<Name> unique_name, |
| TNode<Object> value, LanguageMode language_mode); |
| |
| // [[Set]], but more generic than the above. This impl does essentially the |
| // same as "KeyedStoreGeneric" but does not use feedback slot and uses a |
| // hardcoded LanguageMode instead of trying to deduce it from the feedback |
| // slot's kind. |
| void SetProperty(TNode<Context> context, TNode<Object> receiver, |
| TNode<Object> key, TNode<Object> value, |
| LanguageMode language_mode); |
| |
| private: |
| StoreMode mode_; |
| |
| enum UpdateLength { |
| kDontChangeLength, |
| kIncrementLengthByOne, |
| kBumpLengthWithGap |
| }; |
| |
| enum UseStubCache { kUseStubCache, kDontUseStubCache }; |
| |
| // Helper that is used by the public KeyedStoreGeneric and by SetProperty. |
| void KeyedStoreGeneric(TNode<Context> context, TNode<Object> receiver, |
| TNode<Object> key, TNode<Object> value, |
| Maybe<LanguageMode> language_mode); |
| |
| void EmitGenericElementStore(Node* receiver, Node* receiver_map, |
| Node* instance_type, Node* intptr_index, |
| Node* value, Node* context, Label* slow); |
| |
| // If language mode is not provided it is deduced from the feedback slot's |
| // kind. |
| void EmitGenericPropertyStore(TNode<JSReceiver> receiver, |
| TNode<Map> receiver_map, |
| const StoreICParameters* p, |
| ExitPoint* exit_point, Label* slow, |
| Maybe<LanguageMode> maybe_language_mode); |
| |
| void EmitGenericPropertyStore(SloppyTNode<JSReceiver> receiver, |
| SloppyTNode<Map> receiver_map, |
| const StoreICParameters* p, Label* slow) { |
| ExitPoint direct_exit(this); |
| EmitGenericPropertyStore(receiver, receiver_map, p, &direct_exit, slow, |
| Nothing<LanguageMode>()); |
| } |
| |
| void BranchIfPrototypesHaveNonFastElements(Node* receiver_map, |
| Label* non_fast_elements, |
| Label* only_fast_elements); |
| |
| void TryRewriteElements(Node* receiver, Node* receiver_map, Node* elements, |
| Node* native_context, ElementsKind from_kind, |
| ElementsKind to_kind, Label* bailout); |
| |
| void StoreElementWithCapacity(Node* receiver, Node* receiver_map, |
| Node* elements, Node* elements_kind, |
| Node* intptr_index, Node* value, Node* context, |
| Label* slow, UpdateLength update_length); |
| |
| void MaybeUpdateLengthAndReturn(Node* receiver, Node* index, Node* value, |
| UpdateLength update_length); |
| |
| void TryChangeToHoleyMapHelper(Node* receiver, Node* receiver_map, |
| Node* native_context, ElementsKind packed_kind, |
| ElementsKind holey_kind, Label* done, |
| Label* map_mismatch, Label* bailout); |
| void TryChangeToHoleyMap(Node* receiver, Node* receiver_map, |
| Node* current_elements_kind, Node* context, |
| ElementsKind packed_kind, Label* bailout); |
| void TryChangeToHoleyMapMulti(Node* receiver, Node* receiver_map, |
| Node* current_elements_kind, Node* context, |
| ElementsKind packed_kind, |
| ElementsKind packed_kind_2, Label* bailout); |
| |
| void LookupPropertyOnPrototypeChain(Node* receiver_map, Node* name, |
| Label* accessor, |
| Variable* var_accessor_pair, |
| Variable* var_accessor_holder, |
| Label* readonly, Label* bailout); |
| |
| TNode<Map> FindCandidateStoreICTransitionMapHandler(TNode<Map> map, |
| TNode<Name> name, |
| Label* slow); |
| |
| bool IsKeyedStore() const { return mode_ == StoreMode::kOrdinary; } |
| bool IsStoreInLiteral() const { return mode_ == StoreMode::kInLiteral; } |
| |
| bool ShouldCheckPrototype() const { return IsKeyedStore(); } |
| bool ShouldReconfigureExisting() const { return IsStoreInLiteral(); } |
| bool ShouldCallSetter() const { return IsKeyedStore(); } |
| bool ShouldCheckPrototypeValidity() const { |
| // We don't do this for "in-literal" stores, because it is impossible for |
| // the target object to be a "prototype" |
| return !IsStoreInLiteral(); |
| } |
| }; |
| |
| void KeyedStoreGenericGenerator::Generate(compiler::CodeAssemblerState* state) { |
| KeyedStoreGenericAssembler assembler(state, StoreMode::kOrdinary); |
| assembler.KeyedStoreGeneric(); |
| } |
| |
| void StoreICUninitializedGenerator::Generate( |
| compiler::CodeAssemblerState* state) { |
| KeyedStoreGenericAssembler assembler(state, StoreMode::kOrdinary); |
| assembler.StoreIC_Uninitialized(); |
| } |
| |
| void KeyedStoreGenericGenerator::SetProperty( |
| compiler::CodeAssemblerState* state, TNode<Context> context, |
| TNode<JSReceiver> receiver, TNode<BoolT> is_simple_receiver, |
| TNode<Name> name, TNode<Object> value, LanguageMode language_mode) { |
| KeyedStoreGenericAssembler assembler(state, StoreMode::kOrdinary); |
| assembler.SetProperty(context, receiver, is_simple_receiver, name, value, |
| language_mode); |
| } |
| |
| void KeyedStoreGenericGenerator::SetProperty( |
| compiler::CodeAssemblerState* state, TNode<Context> context, |
| TNode<Object> receiver, TNode<Object> key, TNode<Object> value, |
| LanguageMode language_mode) { |
| KeyedStoreGenericAssembler assembler(state, StoreMode::kOrdinary); |
| assembler.SetProperty(context, receiver, key, value, language_mode); |
| } |
| |
| void KeyedStoreGenericGenerator::SetPropertyInLiteral( |
| compiler::CodeAssemblerState* state, TNode<Context> context, |
| TNode<JSObject> receiver, TNode<Object> key, TNode<Object> value) { |
| KeyedStoreGenericAssembler assembler(state, StoreMode::kInLiteral); |
| assembler.SetProperty(context, receiver, key, value, LanguageMode::kStrict); |
| } |
| |
| void KeyedStoreGenericAssembler::BranchIfPrototypesHaveNonFastElements( |
| Node* receiver_map, Label* non_fast_elements, Label* only_fast_elements) { |
| VARIABLE(var_map, MachineRepresentation::kTagged); |
| var_map.Bind(receiver_map); |
| Label loop_body(this, &var_map); |
| Goto(&loop_body); |
| |
| BIND(&loop_body); |
| { |
| Node* map = var_map.value(); |
| Node* prototype = LoadMapPrototype(map); |
| GotoIf(IsNull(prototype), only_fast_elements); |
| Node* prototype_map = LoadMap(prototype); |
| var_map.Bind(prototype_map); |
| TNode<Int32T> instance_type = LoadMapInstanceType(prototype_map); |
| GotoIf(IsCustomElementsReceiverInstanceType(instance_type), |
| non_fast_elements); |
| TNode<Int32T> elements_kind = LoadMapElementsKind(prototype_map); |
| GotoIf(IsFastElementsKind(elements_kind), &loop_body); |
| GotoIf(Word32Equal(elements_kind, Int32Constant(NO_ELEMENTS)), &loop_body); |
| Goto(non_fast_elements); |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::TryRewriteElements( |
| Node* receiver, Node* receiver_map, Node* elements, Node* native_context, |
| ElementsKind from_kind, ElementsKind to_kind, Label* bailout) { |
| DCHECK(IsFastPackedElementsKind(from_kind)); |
| ElementsKind holey_from_kind = GetHoleyElementsKind(from_kind); |
| ElementsKind holey_to_kind = GetHoleyElementsKind(to_kind); |
| if (AllocationSite::ShouldTrack(from_kind, to_kind)) { |
| TrapAllocationMemento(receiver, bailout); |
| } |
| Label perform_transition(this), check_holey_map(this); |
| VARIABLE(var_target_map, MachineRepresentation::kTagged); |
| // Check if the receiver has the default |from_kind| map. |
| { |
| Node* packed_map = LoadJSArrayElementsMap(from_kind, native_context); |
| GotoIf(WordNotEqual(receiver_map, packed_map), &check_holey_map); |
| var_target_map.Bind( |
| LoadContextElement(native_context, Context::ArrayMapIndex(to_kind))); |
| Goto(&perform_transition); |
| } |
| |
| // Check if the receiver has the default |holey_from_kind| map. |
| BIND(&check_holey_map); |
| { |
| Node* holey_map = LoadContextElement( |
| native_context, Context::ArrayMapIndex(holey_from_kind)); |
| GotoIf(WordNotEqual(receiver_map, holey_map), bailout); |
| var_target_map.Bind(LoadContextElement( |
| native_context, Context::ArrayMapIndex(holey_to_kind))); |
| Goto(&perform_transition); |
| } |
| |
| // Found a supported transition target map, perform the transition! |
| BIND(&perform_transition); |
| { |
| if (IsDoubleElementsKind(from_kind) != IsDoubleElementsKind(to_kind)) { |
| Node* capacity = SmiUntag(LoadFixedArrayBaseLength(elements)); |
| GrowElementsCapacity(receiver, elements, from_kind, to_kind, capacity, |
| capacity, INTPTR_PARAMETERS, bailout); |
| } |
| StoreMap(receiver, var_target_map.value()); |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::TryChangeToHoleyMapHelper( |
| Node* receiver, Node* receiver_map, Node* native_context, |
| ElementsKind packed_kind, ElementsKind holey_kind, Label* done, |
| Label* map_mismatch, Label* bailout) { |
| Node* packed_map = LoadJSArrayElementsMap(packed_kind, native_context); |
| GotoIf(WordNotEqual(receiver_map, packed_map), map_mismatch); |
| if (AllocationSite::ShouldTrack(packed_kind, holey_kind)) { |
| TrapAllocationMemento(receiver, bailout); |
| } |
| Node* holey_map = |
| LoadContextElement(native_context, Context::ArrayMapIndex(holey_kind)); |
| StoreMap(receiver, holey_map); |
| Goto(done); |
| } |
| |
| void KeyedStoreGenericAssembler::TryChangeToHoleyMap( |
| Node* receiver, Node* receiver_map, Node* current_elements_kind, |
| Node* context, ElementsKind packed_kind, Label* bailout) { |
| ElementsKind holey_kind = GetHoleyElementsKind(packed_kind); |
| Label already_holey(this); |
| |
| GotoIf(Word32Equal(current_elements_kind, Int32Constant(holey_kind)), |
| &already_holey); |
| Node* native_context = LoadNativeContext(context); |
| TryChangeToHoleyMapHelper(receiver, receiver_map, native_context, packed_kind, |
| holey_kind, &already_holey, bailout, bailout); |
| BIND(&already_holey); |
| } |
| |
| void KeyedStoreGenericAssembler::TryChangeToHoleyMapMulti( |
| Node* receiver, Node* receiver_map, Node* current_elements_kind, |
| Node* context, ElementsKind packed_kind, ElementsKind packed_kind_2, |
| Label* bailout) { |
| ElementsKind holey_kind = GetHoleyElementsKind(packed_kind); |
| ElementsKind holey_kind_2 = GetHoleyElementsKind(packed_kind_2); |
| Label already_holey(this), check_other_kind(this); |
| |
| GotoIf(Word32Equal(current_elements_kind, Int32Constant(holey_kind)), |
| &already_holey); |
| GotoIf(Word32Equal(current_elements_kind, Int32Constant(holey_kind_2)), |
| &already_holey); |
| |
| Node* native_context = LoadNativeContext(context); |
| TryChangeToHoleyMapHelper(receiver, receiver_map, native_context, packed_kind, |
| holey_kind, &already_holey, &check_other_kind, |
| bailout); |
| BIND(&check_other_kind); |
| TryChangeToHoleyMapHelper(receiver, receiver_map, native_context, |
| packed_kind_2, holey_kind_2, &already_holey, |
| bailout, bailout); |
| BIND(&already_holey); |
| } |
| |
| void KeyedStoreGenericAssembler::MaybeUpdateLengthAndReturn( |
| Node* receiver, Node* index, Node* value, UpdateLength update_length) { |
| if (update_length != kDontChangeLength) { |
| Node* new_length = SmiTag(Signed(IntPtrAdd(index, IntPtrConstant(1)))); |
| StoreObjectFieldNoWriteBarrier(receiver, JSArray::kLengthOffset, new_length, |
| MachineRepresentation::kTagged); |
| } |
| Return(value); |
| } |
| |
| void KeyedStoreGenericAssembler::StoreElementWithCapacity( |
| Node* receiver, Node* receiver_map, Node* elements, Node* elements_kind, |
| Node* intptr_index, Node* value, Node* context, Label* slow, |
| UpdateLength update_length) { |
| if (update_length != kDontChangeLength) { |
| CSA_ASSERT(this, InstanceTypeEqual(LoadMapInstanceType(receiver_map), |
| JS_ARRAY_TYPE)); |
| // Check if the length property is writable. The fast check is only |
| // supported for fast properties. |
| GotoIf(IsDictionaryMap(receiver_map), slow); |
| // The length property is non-configurable, so it's guaranteed to always |
| // be the first property. |
| TNode<DescriptorArray> descriptors = LoadMapDescriptors(receiver_map); |
| TNode<Uint32T> details = LoadDetailsByDescriptorEntry(descriptors, 0); |
| GotoIf(IsSetWord32(details, PropertyDetails::kAttributesReadOnlyMask), |
| slow); |
| } |
| STATIC_ASSERT(FixedArray::kHeaderSize == FixedDoubleArray::kHeaderSize); |
| const int kHeaderSize = FixedArray::kHeaderSize - kHeapObjectTag; |
| |
| Label check_double_elements(this), check_cow_elements(this); |
| Node* elements_map = LoadMap(elements); |
| GotoIf(WordNotEqual(elements_map, LoadRoot(RootIndex::kFixedArrayMap)), |
| &check_double_elements); |
| |
| // FixedArray backing store -> Smi or object elements. |
| { |
| Node* offset = ElementOffsetFromIndex(intptr_index, PACKED_ELEMENTS, |
| INTPTR_PARAMETERS, kHeaderSize); |
| // Check if we're about to overwrite the hole. We can safely do that |
| // only if there can be no setters on the prototype chain. |
| // If we know that we're storing beyond the previous array length, we |
| // can skip the hole check (and always assume the hole). |
| { |
| Label hole_check_passed(this); |
| if (update_length == kDontChangeLength) { |
| Node* element = Load(MachineType::AnyTagged(), elements, offset); |
| GotoIf(WordNotEqual(element, TheHoleConstant()), &hole_check_passed); |
| } |
| BranchIfPrototypesHaveNonFastElements(receiver_map, slow, |
| &hole_check_passed); |
| BIND(&hole_check_passed); |
| } |
| |
| // Check if the value we're storing matches the elements_kind. Smis |
| // can always be stored. |
| { |
| Label non_smi_value(this); |
| GotoIfNot(TaggedIsSmi(value), &non_smi_value); |
| // If we're about to introduce holes, ensure holey elements. |
| if (update_length == kBumpLengthWithGap) { |
| TryChangeToHoleyMapMulti(receiver, receiver_map, elements_kind, context, |
| PACKED_SMI_ELEMENTS, PACKED_ELEMENTS, slow); |
| } |
| StoreNoWriteBarrier(MachineRepresentation::kTaggedSigned, elements, |
| offset, value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, update_length); |
| |
| BIND(&non_smi_value); |
| } |
| |
| // Check if we already have object elements; just do the store if so. |
| { |
| Label must_transition(this); |
| STATIC_ASSERT(PACKED_SMI_ELEMENTS == 0); |
| STATIC_ASSERT(HOLEY_SMI_ELEMENTS == 1); |
| GotoIf(Int32LessThanOrEqual(elements_kind, |
| Int32Constant(HOLEY_SMI_ELEMENTS)), |
| &must_transition); |
| if (update_length == kBumpLengthWithGap) { |
| TryChangeToHoleyMap(receiver, receiver_map, elements_kind, context, |
| PACKED_ELEMENTS, slow); |
| } |
| Store(elements, offset, value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, update_length); |
| |
| BIND(&must_transition); |
| } |
| |
| // Transition to the required ElementsKind. |
| { |
| Label transition_to_double(this), transition_to_object(this); |
| Node* native_context = LoadNativeContext(context); |
| Branch(WordEqual(LoadMap(value), LoadRoot(RootIndex::kHeapNumberMap)), |
| &transition_to_double, &transition_to_object); |
| BIND(&transition_to_double); |
| { |
| // If we're adding holes at the end, always transition to a holey |
| // elements kind, otherwise try to remain packed. |
| ElementsKind target_kind = update_length == kBumpLengthWithGap |
| ? HOLEY_DOUBLE_ELEMENTS |
| : PACKED_DOUBLE_ELEMENTS; |
| TryRewriteElements(receiver, receiver_map, elements, native_context, |
| PACKED_SMI_ELEMENTS, target_kind, slow); |
| // Reload migrated elements. |
| Node* double_elements = LoadElements(receiver); |
| Node* double_offset = |
| ElementOffsetFromIndex(intptr_index, PACKED_DOUBLE_ELEMENTS, |
| INTPTR_PARAMETERS, kHeaderSize); |
| // Make sure we do not store signalling NaNs into double arrays. |
| Node* double_value = Float64SilenceNaN(LoadHeapNumberValue(value)); |
| StoreNoWriteBarrier(MachineRepresentation::kFloat64, double_elements, |
| double_offset, double_value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, |
| update_length); |
| } |
| |
| BIND(&transition_to_object); |
| { |
| // If we're adding holes at the end, always transition to a holey |
| // elements kind, otherwise try to remain packed. |
| ElementsKind target_kind = update_length == kBumpLengthWithGap |
| ? HOLEY_ELEMENTS |
| : PACKED_ELEMENTS; |
| TryRewriteElements(receiver, receiver_map, elements, native_context, |
| PACKED_SMI_ELEMENTS, target_kind, slow); |
| // The elements backing store didn't change, no reload necessary. |
| CSA_ASSERT(this, WordEqual(elements, LoadElements(receiver))); |
| Store(elements, offset, value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, |
| update_length); |
| } |
| } |
| } |
| |
| BIND(&check_double_elements); |
| Node* fixed_double_array_map = LoadRoot(RootIndex::kFixedDoubleArrayMap); |
| GotoIf(WordNotEqual(elements_map, fixed_double_array_map), |
| &check_cow_elements); |
| // FixedDoubleArray backing store -> double elements. |
| { |
| Node* offset = ElementOffsetFromIndex(intptr_index, PACKED_DOUBLE_ELEMENTS, |
| INTPTR_PARAMETERS, kHeaderSize); |
| // Check if we're about to overwrite the hole. We can safely do that |
| // only if there can be no setters on the prototype chain. |
| { |
| Label hole_check_passed(this); |
| // If we know that we're storing beyond the previous array length, we |
| // can skip the hole check (and always assume the hole). |
| if (update_length == kDontChangeLength) { |
| Label found_hole(this); |
| LoadDoubleWithHoleCheck(elements, offset, &found_hole, |
| MachineType::None()); |
| Goto(&hole_check_passed); |
| BIND(&found_hole); |
| } |
| BranchIfPrototypesHaveNonFastElements(receiver_map, slow, |
| &hole_check_passed); |
| BIND(&hole_check_passed); |
| } |
| |
| // Try to store the value as a double. |
| { |
| Label non_number_value(this); |
| Node* double_value = TryTaggedToFloat64(value, &non_number_value); |
| |
| // Make sure we do not store signalling NaNs into double arrays. |
| double_value = Float64SilenceNaN(double_value); |
| // If we're about to introduce holes, ensure holey elements. |
| if (update_length == kBumpLengthWithGap) { |
| TryChangeToHoleyMap(receiver, receiver_map, elements_kind, context, |
| PACKED_DOUBLE_ELEMENTS, slow); |
| } |
| StoreNoWriteBarrier(MachineRepresentation::kFloat64, elements, offset, |
| double_value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, update_length); |
| |
| BIND(&non_number_value); |
| } |
| |
| // Transition to object elements. |
| { |
| Node* native_context = LoadNativeContext(context); |
| ElementsKind target_kind = update_length == kBumpLengthWithGap |
| ? HOLEY_ELEMENTS |
| : PACKED_ELEMENTS; |
| TryRewriteElements(receiver, receiver_map, elements, native_context, |
| PACKED_DOUBLE_ELEMENTS, target_kind, slow); |
| // Reload migrated elements. |
| Node* fast_elements = LoadElements(receiver); |
| Node* fast_offset = ElementOffsetFromIndex( |
| intptr_index, PACKED_ELEMENTS, INTPTR_PARAMETERS, kHeaderSize); |
| Store(fast_elements, fast_offset, value); |
| MaybeUpdateLengthAndReturn(receiver, intptr_index, value, update_length); |
| } |
| } |
| |
| BIND(&check_cow_elements); |
| { |
| // TODO(jkummerow): Use GrowElementsCapacity instead of bailing out. |
| Goto(slow); |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::EmitGenericElementStore( |
| Node* receiver, Node* receiver_map, Node* instance_type, Node* intptr_index, |
| Node* value, Node* context, Label* slow) { |
| Label if_fast(this), if_in_bounds(this), if_out_of_bounds(this), |
| if_increment_length_by_one(this), if_bump_length_with_gap(this), |
| if_grow(this), if_nonfast(this), if_typed_array(this), |
| if_dictionary(this); |
| Node* elements = LoadElements(receiver); |
| TNode<Int32T> elements_kind = LoadMapElementsKind(receiver_map); |
| Branch(IsFastElementsKind(elements_kind), &if_fast, &if_nonfast); |
| BIND(&if_fast); |
| |
| Label if_array(this); |
| GotoIf(InstanceTypeEqual(instance_type, JS_ARRAY_TYPE), &if_array); |
| { |
| Node* capacity = SmiUntag(LoadFixedArrayBaseLength(elements)); |
| Branch(UintPtrLessThan(intptr_index, capacity), &if_in_bounds, |
| &if_out_of_bounds); |
| } |
| BIND(&if_array); |
| { |
| Node* length = SmiUntag(LoadFastJSArrayLength(receiver)); |
| GotoIf(UintPtrLessThan(intptr_index, length), &if_in_bounds); |
| Node* capacity = SmiUntag(LoadFixedArrayBaseLength(elements)); |
| GotoIf(UintPtrGreaterThanOrEqual(intptr_index, capacity), &if_grow); |
| Branch(WordEqual(intptr_index, length), &if_increment_length_by_one, |
| &if_bump_length_with_gap); |
| } |
| |
| BIND(&if_in_bounds); |
| { |
| StoreElementWithCapacity(receiver, receiver_map, elements, elements_kind, |
| intptr_index, value, context, slow, |
| kDontChangeLength); |
| } |
| |
| BIND(&if_out_of_bounds); |
| { |
| // Integer indexed out-of-bounds accesses to typed arrays are simply |
| // ignored, since we never look up integer indexed properties on the |
| // prototypes of typed arrays. For all other types, we may need to |
| // grow the backing store. |
| GotoIfNot(InstanceTypeEqual(instance_type, JS_TYPED_ARRAY_TYPE), &if_grow); |
| Return(value); |
| } |
| |
| BIND(&if_increment_length_by_one); |
| { |
| StoreElementWithCapacity(receiver, receiver_map, elements, elements_kind, |
| intptr_index, value, context, slow, |
| kIncrementLengthByOne); |
| } |
| |
| BIND(&if_bump_length_with_gap); |
| { |
| StoreElementWithCapacity(receiver, receiver_map, elements, elements_kind, |
| intptr_index, value, context, slow, |
| kBumpLengthWithGap); |
| } |
| |
| // Out-of-capacity accesses (index >= capacity) jump here. Additionally, |
| // an ElementsKind transition might be necessary. |
| // The index can also be negative at this point! Jump to the runtime in that |
| // case to convert it to a named property. |
| BIND(&if_grow); |
| { |
| Comment("Grow backing store"); |
| // TODO(jkummerow): Support inline backing store growth. |
| Goto(slow); |
| } |
| |
| // Any ElementsKind > LAST_FAST_ELEMENTS_KIND jumps here for further |
| // dispatch. |
| BIND(&if_nonfast); |
| { |
| STATIC_ASSERT(LAST_ELEMENTS_KIND == LAST_FIXED_TYPED_ARRAY_ELEMENTS_KIND); |
| GotoIf(Int32GreaterThanOrEqual( |
| elements_kind, |
| Int32Constant(FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND)), |
| &if_typed_array); |
| GotoIf(Word32Equal(elements_kind, Int32Constant(DICTIONARY_ELEMENTS)), |
| &if_dictionary); |
| Goto(slow); |
| } |
| |
| BIND(&if_dictionary); |
| { |
| Comment("Dictionary"); |
| // TODO(jkummerow): Support storing to dictionary elements. |
| Goto(slow); |
| } |
| |
| BIND(&if_typed_array); |
| { |
| Comment("Typed array"); |
| // TODO(jkummerow): Support typed arrays. |
| Goto(slow); |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::LookupPropertyOnPrototypeChain( |
| Node* receiver_map, Node* name, Label* accessor, |
| Variable* var_accessor_pair, Variable* var_accessor_holder, Label* readonly, |
| Label* bailout) { |
| Label ok_to_write(this); |
| VARIABLE(var_holder, MachineRepresentation::kTagged); |
| var_holder.Bind(LoadMapPrototype(receiver_map)); |
| VARIABLE(var_holder_map, MachineRepresentation::kTagged); |
| var_holder_map.Bind(LoadMap(var_holder.value())); |
| |
| Variable* merged_variables[] = {&var_holder, &var_holder_map}; |
| Label loop(this, arraysize(merged_variables), merged_variables); |
| Goto(&loop); |
| BIND(&loop); |
| { |
| Node* holder = var_holder.value(); |
| GotoIf(IsNull(holder), &ok_to_write); |
| Node* holder_map = var_holder_map.value(); |
| Node* instance_type = LoadMapInstanceType(holder_map); |
| Label next_proto(this); |
| { |
| Label found(this), found_fast(this), found_dict(this), found_global(this); |
| TVARIABLE(HeapObject, var_meta_storage); |
| TVARIABLE(IntPtrT, var_entry); |
| TryLookupProperty(holder, holder_map, instance_type, name, &found_fast, |
| &found_dict, &found_global, &var_meta_storage, |
| &var_entry, &next_proto, bailout); |
| BIND(&found_fast); |
| { |
| TNode<DescriptorArray> descriptors = CAST(var_meta_storage.value()); |
| TNode<IntPtrT> name_index = var_entry.value(); |
| Node* details = LoadDetailsByKeyIndex(descriptors, name_index); |
| JumpIfDataProperty(details, &ok_to_write, readonly); |
| |
| // Accessor case. |
| // TODO(jkummerow): Implement a trimmed-down |
| // LoadAccessorFromFastObject. |
| VARIABLE(var_details, MachineRepresentation::kWord32); |
| LoadPropertyFromFastObject(holder, holder_map, descriptors, name_index, |
| &var_details, var_accessor_pair); |
| var_accessor_holder->Bind(holder); |
| Goto(accessor); |
| } |
| |
| BIND(&found_dict); |
| { |
| Node* dictionary = var_meta_storage.value(); |
| Node* entry = var_entry.value(); |
| Node* details = |
| LoadDetailsByKeyIndex<NameDictionary>(dictionary, entry); |
| JumpIfDataProperty(details, &ok_to_write, readonly); |
| |
| if (accessor != nullptr) { |
| // Accessor case. |
| var_accessor_pair->Bind( |
| LoadValueByKeyIndex<NameDictionary>(dictionary, entry)); |
| var_accessor_holder->Bind(holder); |
| Goto(accessor); |
| } else { |
| Goto(&ok_to_write); |
| } |
| } |
| |
| BIND(&found_global); |
| { |
| Node* dictionary = var_meta_storage.value(); |
| Node* entry = var_entry.value(); |
| Node* property_cell = |
| LoadValueByKeyIndex<GlobalDictionary>(dictionary, entry); |
| Node* value = |
| LoadObjectField(property_cell, PropertyCell::kValueOffset); |
| GotoIf(WordEqual(value, TheHoleConstant()), &next_proto); |
| Node* details = LoadAndUntagToWord32ObjectField( |
| property_cell, PropertyCell::kPropertyDetailsRawOffset); |
| JumpIfDataProperty(details, &ok_to_write, readonly); |
| |
| if (accessor != nullptr) { |
| // Accessor case. |
| var_accessor_pair->Bind(value); |
| var_accessor_holder->Bind(holder); |
| Goto(accessor); |
| } else { |
| Goto(&ok_to_write); |
| } |
| } |
| } |
| |
| BIND(&next_proto); |
| // Bailout if it can be an integer indexed exotic case. |
| GotoIf(InstanceTypeEqual(instance_type, JS_TYPED_ARRAY_TYPE), bailout); |
| Node* proto = LoadMapPrototype(holder_map); |
| GotoIf(IsNull(proto), &ok_to_write); |
| var_holder.Bind(proto); |
| var_holder_map.Bind(LoadMap(proto)); |
| Goto(&loop); |
| } |
| BIND(&ok_to_write); |
| } |
| |
| TNode<Map> KeyedStoreGenericAssembler::FindCandidateStoreICTransitionMapHandler( |
| TNode<Map> map, TNode<Name> name, Label* slow) { |
| TVARIABLE(Map, var_transition_map); |
| Label simple_transition(this), transition_array(this), |
| found_handler_candidate(this); |
| |
| TNode<MaybeObject> maybe_handler = |
| LoadMaybeWeakObjectField(map, Map::kTransitionsOrPrototypeInfoOffset); |
| |
| // Smi -> slow, |
| // Cleared weak reference -> slow |
| // weak reference -> simple_transition |
| // strong reference -> transition_array |
| TVARIABLE(Object, var_transition_map_or_array); |
| DispatchMaybeObject(maybe_handler, slow, slow, &simple_transition, |
| &transition_array, &var_transition_map_or_array); |
| |
| BIND(&simple_transition); |
| { |
| var_transition_map = CAST(var_transition_map_or_array.value()); |
| Goto(&found_handler_candidate); |
| } |
| |
| BIND(&transition_array); |
| { |
| TNode<Map> maybe_handler_map = |
| LoadMap(CAST(var_transition_map_or_array.value())); |
| GotoIfNot(IsTransitionArrayMap(maybe_handler_map), slow); |
| |
| TVARIABLE(IntPtrT, var_name_index); |
| Label if_found_candidate(this); |
| TNode<TransitionArray> transitions = |
| CAST(var_transition_map_or_array.value()); |
| TransitionLookup(name, transitions, &if_found_candidate, &var_name_index, |
| slow); |
| |
| BIND(&if_found_candidate); |
| { |
| // Given that |
| // 1) transitions with the same name are ordered in the transition |
| // array by PropertyKind and then by PropertyAttributes values, |
| // 2) kData < kAccessor, |
| // 3) NONE == 0, |
| // 4) properties with private symbol names are guaranteed to be |
| // non-enumerable (so DONT_ENUM bit in attributes is always set), |
| // the resulting map of transitioning store if it exists in the |
| // transition array is expected to be the first among the transitions |
| // with the same name. |
| // See TransitionArray::CompareDetails() for details. |
| STATIC_ASSERT(kData == 0); |
| STATIC_ASSERT(NONE == 0); |
| const int kKeyToTargetOffset = (TransitionArray::kEntryTargetIndex - |
| TransitionArray::kEntryKeyIndex) * |
| kTaggedSize; |
| var_transition_map = CAST(GetHeapObjectAssumeWeak( |
| LoadArrayElement(transitions, WeakFixedArray::kHeaderSize, |
| var_name_index.value(), kKeyToTargetOffset))); |
| Goto(&found_handler_candidate); |
| } |
| } |
| |
| BIND(&found_handler_candidate); |
| return var_transition_map.value(); |
| } |
| |
| void KeyedStoreGenericAssembler::EmitGenericPropertyStore( |
| TNode<JSReceiver> receiver, TNode<Map> receiver_map, |
| const StoreICParameters* p, ExitPoint* exit_point, Label* slow, |
| Maybe<LanguageMode> maybe_language_mode) { |
| CSA_ASSERT(this, IsSimpleObjectMap(receiver_map)); |
| VARIABLE(var_accessor_pair, MachineRepresentation::kTagged); |
| VARIABLE(var_accessor_holder, MachineRepresentation::kTagged); |
| Label fast_properties(this), dictionary_properties(this), accessor(this), |
| readonly(this); |
| Node* bitfield3 = LoadMapBitField3(receiver_map); |
| Branch(IsSetWord32<Map::IsDictionaryMapBit>(bitfield3), |
| &dictionary_properties, &fast_properties); |
| |
| BIND(&fast_properties); |
| { |
| Comment("fast property store"); |
| TNode<DescriptorArray> descriptors = LoadMapDescriptors(receiver_map); |
| Label descriptor_found(this), lookup_transition(this); |
| TVARIABLE(IntPtrT, var_name_index); |
| DescriptorLookup(p->name(), descriptors, bitfield3, &descriptor_found, |
| &var_name_index, &lookup_transition); |
| |
| BIND(&descriptor_found); |
| { |
| TNode<IntPtrT> name_index = var_name_index.value(); |
| Node* details = LoadDetailsByKeyIndex(descriptors, name_index); |
| Label data_property(this); |
| JumpIfDataProperty(details, &data_property, |
| ShouldReconfigureExisting() ? nullptr : &readonly); |
| |
| if (ShouldCallSetter()) { |
| // Accessor case. |
| // TODO(jkummerow): Implement a trimmed-down LoadAccessorFromFastObject. |
| VARIABLE(var_details, MachineRepresentation::kWord32); |
| LoadPropertyFromFastObject(receiver, receiver_map, descriptors, |
| name_index, &var_details, |
| &var_accessor_pair); |
| var_accessor_holder.Bind(receiver); |
| Goto(&accessor); |
| } else { |
| Goto(&data_property); |
| } |
| |
| BIND(&data_property); |
| { |
| CheckForAssociatedProtector(p->name(), slow); |
| OverwriteExistingFastDataProperty(receiver, receiver_map, descriptors, |
| name_index, details, p->value(), slow, |
| false); |
| exit_point->Return(p->value()); |
| } |
| } |
| BIND(&lookup_transition); |
| { |
| Comment("lookup transition"); |
| TNode<Map> transition_map = FindCandidateStoreICTransitionMapHandler( |
| receiver_map, CAST(p->name()), slow); |
| |
| // Validate the transition handler candidate and apply the transition. |
| StoreTransitionMapFlags flags = kValidateTransitionHandler; |
| if (ShouldCheckPrototypeValidity()) { |
| flags = StoreTransitionMapFlags(flags | kCheckPrototypeValidity); |
| } |
| HandleStoreICTransitionMapHandlerCase(p, transition_map, slow, flags); |
| exit_point->Return(p->value()); |
| } |
| } |
| |
| BIND(&dictionary_properties); |
| { |
| Comment("dictionary property store"); |
| // We checked for LAST_CUSTOM_ELEMENTS_RECEIVER before, which rules out |
| // seeing global objects here (which would need special handling). |
| |
| TVARIABLE(IntPtrT, var_name_index); |
| Label dictionary_found(this, &var_name_index), not_found(this); |
| TNode<NameDictionary> properties = CAST(LoadSlowProperties(CAST(receiver))); |
| NameDictionaryLookup<NameDictionary>(properties, CAST(p->name()), |
| &dictionary_found, &var_name_index, |
| ¬_found); |
| BIND(&dictionary_found); |
| { |
| Label overwrite(this); |
| TNode<Uint32T> details = LoadDetailsByKeyIndex<NameDictionary>( |
| properties, var_name_index.value()); |
| JumpIfDataProperty(details, &overwrite, |
| ShouldReconfigureExisting() ? nullptr : &readonly); |
| |
| if (ShouldCallSetter()) { |
| // Accessor case. |
| var_accessor_pair.Bind(LoadValueByKeyIndex<NameDictionary>( |
| properties, var_name_index.value())); |
| var_accessor_holder.Bind(receiver); |
| Goto(&accessor); |
| } else { |
| // We must reconfigure an accessor property to a data property |
| // here, let the runtime take care of that. |
| Goto(slow); |
| } |
| |
| BIND(&overwrite); |
| { |
| CheckForAssociatedProtector(p->name(), slow); |
| StoreValueByKeyIndex<NameDictionary>(properties, var_name_index.value(), |
| p->value()); |
| exit_point->Return(p->value()); |
| } |
| } |
| |
| BIND(¬_found); |
| { |
| CheckForAssociatedProtector(p->name(), slow); |
| Label extensible(this), is_private_symbol(this); |
| Node* bitfield3 = LoadMapBitField3(receiver_map); |
| GotoIf(IsPrivateSymbol(p->name()), &is_private_symbol); |
| Branch(IsSetWord32<Map::IsExtensibleBit>(bitfield3), &extensible, slow); |
| |
| BIND(&is_private_symbol); |
| { |
| CSA_ASSERT(this, IsPrivateSymbol(p->name())); |
| // For private names, we miss to the runtime which will throw. |
| // For private symbols, we extend and store an own property. |
| Branch(IsPrivateName(p->name()), slow, &extensible); |
| } |
| |
| BIND(&extensible); |
| if (ShouldCheckPrototype()) { |
| DCHECK(ShouldCallSetter()); |
| LookupPropertyOnPrototypeChain( |
| receiver_map, p->name(), &accessor, &var_accessor_pair, |
| &var_accessor_holder, |
| ShouldReconfigureExisting() ? nullptr : &readonly, slow); |
| } |
| Label add_dictionary_property_slow(this); |
| InvalidateValidityCellIfPrototype(receiver_map, bitfield3); |
| Add<NameDictionary>(properties, CAST(p->name()), p->value(), |
| &add_dictionary_property_slow); |
| exit_point->Return(p->value()); |
| |
| BIND(&add_dictionary_property_slow); |
| exit_point->ReturnCallRuntime(Runtime::kAddDictionaryProperty, |
| p->context(), p->receiver(), p->name(), |
| p->value()); |
| } |
| } |
| |
| if (ShouldCallSetter()) { |
| BIND(&accessor); |
| { |
| Label not_callable(this); |
| Node* accessor_pair = var_accessor_pair.value(); |
| GotoIf(IsAccessorInfoMap(LoadMap(accessor_pair)), slow); |
| CSA_ASSERT(this, HasInstanceType(accessor_pair, ACCESSOR_PAIR_TYPE)); |
| Node* setter = |
| LoadObjectField(accessor_pair, AccessorPair::kSetterOffset); |
| Node* setter_map = LoadMap(setter); |
| // FunctionTemplateInfo setters are not supported yet. |
| GotoIf(IsFunctionTemplateInfoMap(setter_map), slow); |
| GotoIfNot(IsCallableMap(setter_map), ¬_callable); |
| |
| Callable callable = CodeFactory::Call(isolate()); |
| CallJS(callable, p->context(), setter, receiver, p->value()); |
| exit_point->Return(p->value()); |
| |
| BIND(¬_callable); |
| { |
| LanguageMode language_mode; |
| if (maybe_language_mode.To(&language_mode)) { |
| if (language_mode == LanguageMode::kStrict) { |
| exit_point->ReturnCallRuntime( |
| Runtime::kThrowTypeError, p->context(), |
| SmiConstant(MessageTemplate::kNoSetterInCallback), p->name(), |
| var_accessor_holder.value()); |
| } else { |
| exit_point->Return(p->value()); |
| } |
| } else { |
| CallRuntime(Runtime::kThrowTypeErrorIfStrict, p->context(), |
| SmiConstant(MessageTemplate::kNoSetterInCallback), |
| p->name(), var_accessor_holder.value()); |
| exit_point->Return(p->value()); |
| } |
| } |
| } |
| } |
| |
| if (!ShouldReconfigureExisting()) { |
| BIND(&readonly); |
| { |
| LanguageMode language_mode; |
| if (maybe_language_mode.To(&language_mode)) { |
| if (language_mode == LanguageMode::kStrict) { |
| Node* type = Typeof(p->receiver()); |
| ThrowTypeError(p->context(), MessageTemplate::kStrictReadOnlyProperty, |
| p->name(), type, p->receiver()); |
| } else { |
| exit_point->Return(p->value()); |
| } |
| } else { |
| CallRuntime(Runtime::kThrowTypeErrorIfStrict, p->context(), |
| SmiConstant(MessageTemplate::kStrictReadOnlyProperty), |
| p->name(), Typeof(p->receiver()), p->receiver()); |
| exit_point->Return(p->value()); |
| } |
| } |
| } |
| } |
| |
| // Helper that is used by the public KeyedStoreGeneric and by SetProperty. |
| void KeyedStoreGenericAssembler::KeyedStoreGeneric( |
| TNode<Context> context, TNode<Object> receiver, TNode<Object> key, |
| TNode<Object> value, Maybe<LanguageMode> language_mode) { |
| TVARIABLE(IntPtrT, var_index); |
| TVARIABLE(Object, var_unique, key); |
| Label if_index(this), if_unique_name(this), not_internalized(this), |
| slow(this); |
| |
| GotoIf(TaggedIsSmi(receiver), &slow); |
| TNode<Map> receiver_map = LoadMap(CAST(receiver)); |
| TNode<Int32T> instance_type = LoadMapInstanceType(receiver_map); |
| // Receivers requiring non-standard element accesses (interceptors, access |
| // checks, strings and string wrappers, proxies) are handled in the runtime. |
| GotoIf(IsCustomElementsReceiverInstanceType(instance_type), &slow); |
| |
| TryToName(key, &if_index, &var_index, &if_unique_name, &var_unique, &slow, |
| ¬_internalized); |
| |
| BIND(&if_index); |
| { |
| Comment("integer index"); |
| EmitGenericElementStore(receiver, receiver_map, instance_type, |
| var_index.value(), value, context, &slow); |
| } |
| |
| BIND(&if_unique_name); |
| { |
| Comment("key is unique name"); |
| StoreICParameters p(context, receiver, var_unique.value(), value, nullptr, |
| nullptr); |
| ExitPoint direct_exit(this); |
| EmitGenericPropertyStore(CAST(receiver), receiver_map, &p, &direct_exit, |
| &slow, language_mode); |
| } |
| |
| BIND(¬_internalized); |
| { |
| if (FLAG_internalize_on_the_fly) { |
| TryInternalizeString(key, &if_index, &var_index, &if_unique_name, |
| &var_unique, &slow, &slow); |
| } else { |
| Goto(&slow); |
| } |
| } |
| |
| BIND(&slow); |
| { |
| if (IsKeyedStore()) { |
| Comment("KeyedStoreGeneric_slow"); |
| TailCallRuntime(Runtime::kSetKeyedProperty, context, receiver, key, |
| value); |
| } else { |
| DCHECK(IsStoreInLiteral()); |
| TailCallRuntime(Runtime::kStoreDataPropertyInLiteral, context, receiver, |
| key, value); |
| } |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::KeyedStoreGeneric() { |
| using Descriptor = StoreDescriptor; |
| |
| TNode<Object> receiver = CAST(Parameter(Descriptor::kReceiver)); |
| TNode<Object> name = CAST(Parameter(Descriptor::kName)); |
| TNode<Object> value = CAST(Parameter(Descriptor::kValue)); |
| TNode<Context> context = CAST(Parameter(Descriptor::kContext)); |
| |
| KeyedStoreGeneric(context, receiver, name, value, Nothing<LanguageMode>()); |
| } |
| |
| void KeyedStoreGenericAssembler::SetProperty(TNode<Context> context, |
| TNode<Object> receiver, |
| TNode<Object> key, |
| TNode<Object> value, |
| LanguageMode language_mode) { |
| KeyedStoreGeneric(context, receiver, key, value, Just(language_mode)); |
| } |
| |
| void KeyedStoreGenericAssembler::StoreIC_Uninitialized() { |
| using Descriptor = StoreWithVectorDescriptor; |
| |
| Node* receiver = Parameter(Descriptor::kReceiver); |
| Node* name = Parameter(Descriptor::kName); |
| Node* value = Parameter(Descriptor::kValue); |
| Node* slot = Parameter(Descriptor::kSlot); |
| Node* vector = Parameter(Descriptor::kVector); |
| Node* context = Parameter(Descriptor::kContext); |
| |
| Label miss(this, Label::kDeferred), store_property(this); |
| |
| GotoIf(TaggedIsSmi(receiver), &miss); |
| Node* receiver_map = LoadMap(receiver); |
| TNode<Int32T> instance_type = LoadMapInstanceType(receiver_map); |
| // Receivers requiring non-standard element accesses (interceptors, access |
| // checks, strings and string wrappers, proxies) are handled in the runtime. |
| GotoIf(IsSpecialReceiverInstanceType(instance_type), &miss); |
| |
| // Optimistically write the state transition to the vector. |
| GotoIf(IsUndefined(vector), &store_property); |
| StoreFeedbackVectorSlot(vector, slot, |
| LoadRoot(RootIndex::kpremonomorphic_symbol), |
| SKIP_WRITE_BARRIER, 0, SMI_PARAMETERS); |
| Goto(&store_property); |
| |
| BIND(&store_property); |
| { |
| StoreICParameters p(CAST(context), receiver, name, value, slot, vector); |
| EmitGenericPropertyStore(receiver, receiver_map, &p, &miss); |
| } |
| |
| BIND(&miss); |
| { |
| Label call_runtime(this); |
| // Undo the optimistic state transition. |
| GotoIf(IsUndefined(vector), &call_runtime); |
| StoreFeedbackVectorSlot(vector, slot, |
| LoadRoot(RootIndex::kuninitialized_symbol), |
| SKIP_WRITE_BARRIER, 0, SMI_PARAMETERS); |
| Goto(&call_runtime); |
| |
| BIND(&call_runtime); |
| TailCallRuntime(Runtime::kStoreIC_Miss, context, value, slot, vector, |
| receiver, name); |
| } |
| } |
| |
| void KeyedStoreGenericAssembler::SetProperty(TNode<Context> context, |
| TNode<JSReceiver> receiver, |
| TNode<BoolT> is_simple_receiver, |
| TNode<Name> unique_name, |
| TNode<Object> value, |
| LanguageMode language_mode) { |
| StoreICParameters p(context, receiver, unique_name, value, nullptr, nullptr); |
| |
| Label done(this), slow(this, Label::kDeferred); |
| ExitPoint exit_point(this, [&](Node* result) { Goto(&done); }); |
| |
| CSA_ASSERT(this, Word32Equal(is_simple_receiver, |
| IsSimpleObjectMap(LoadMap(receiver)))); |
| GotoIfNot(is_simple_receiver, &slow); |
| |
| EmitGenericPropertyStore(receiver, LoadMap(receiver), &p, &exit_point, &slow, |
| Just(language_mode)); |
| |
| BIND(&slow); |
| { |
| if (IsStoreInLiteral()) { |
| CallRuntime(Runtime::kStoreDataPropertyInLiteral, context, receiver, |
| unique_name, value); |
| } else { |
| CallRuntime(Runtime::kSetKeyedProperty, context, receiver, unique_name, |
| value); |
| } |
| Goto(&done); |
| } |
| |
| BIND(&done); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |