| // Copyright 2012 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. |
| |
| #ifndef V8_OBJECTS_TRANSITIONS_INL_H_ |
| #define V8_OBJECTS_TRANSITIONS_INL_H_ |
| |
| #include "src/objects/fixed-array-inl.h" |
| #include "src/objects/maybe-object-inl.h" |
| #include "src/objects/slots.h" |
| #include "src/objects/smi.h" |
| #include "src/objects/transitions.h" |
| |
| // Has to be the last include (doesn't have include guards): |
| #include "src/objects/object-macros.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // static |
| Tagged<TransitionArray> TransitionsAccessor::GetTransitionArray( |
| Isolate* isolate, Tagged<MaybeObject> raw_transitions) { |
| DCHECK_EQ(kFullTransitionArray, GetEncoding(isolate, raw_transitions)); |
| USE(isolate); |
| return TransitionArray::cast(raw_transitions.GetHeapObjectAssumeStrong()); |
| } |
| |
| // static |
| Tagged<TransitionArray> TransitionsAccessor::GetTransitionArray( |
| Isolate* isolate, Handle<Map> map) { |
| Tagged<MaybeObject> raw_transitions = |
| map->raw_transitions(isolate, kAcquireLoad); |
| return GetTransitionArray(isolate, raw_transitions); |
| } |
| |
| Tagged<TransitionArray> TransitionsAccessor::transitions() { |
| return GetTransitionArray(isolate_, raw_transitions_); |
| } |
| |
| OBJECT_CONSTRUCTORS_IMPL(TransitionArray, WeakFixedArray) |
| |
| CAST_ACCESSOR(TransitionArray) |
| |
| bool TransitionArray::HasPrototypeTransitions() { |
| return get(kPrototypeTransitionsIndex) != Smi::zero(); |
| } |
| |
| Tagged<WeakFixedArray> TransitionArray::GetPrototypeTransitions() { |
| DCHECK(HasPrototypeTransitions()); // Callers must check first. |
| Tagged<Object> prototype_transitions = |
| get(kPrototypeTransitionsIndex).GetHeapObjectAssumeStrong(); |
| return WeakFixedArray::cast(prototype_transitions); |
| } |
| |
| HeapObjectSlot TransitionArray::GetKeySlot(int transition_number) { |
| DCHECK(transition_number < number_of_transitions()); |
| return HeapObjectSlot(RawFieldOfElementAt(ToKeyIndex(transition_number))); |
| } |
| |
| void TransitionArray::SetPrototypeTransitions( |
| Tagged<WeakFixedArray> transitions) { |
| DCHECK(IsWeakFixedArray(transitions)); |
| WeakFixedArray::set(kPrototypeTransitionsIndex, transitions); |
| } |
| |
| int TransitionArray::NumberOfPrototypeTransitions( |
| Tagged<WeakFixedArray> proto_transitions) { |
| if (proto_transitions->length() == 0) return 0; |
| Tagged<MaybeObject> raw = |
| proto_transitions->get(kProtoTransitionNumberOfEntriesOffset); |
| return raw.ToSmi().value(); |
| } |
| |
| Tagged<Name> TransitionArray::GetKey(int transition_number) { |
| DCHECK(transition_number < number_of_transitions()); |
| return Name::cast( |
| get(ToKeyIndex(transition_number)).GetHeapObjectAssumeStrong()); |
| } |
| |
| Tagged<Name> TransitionArray::GetKey(InternalIndex index) { |
| return GetKey(index.as_int()); |
| } |
| |
| Tagged<Name> TransitionsAccessor::GetKey(int transition_number) { |
| switch (encoding()) { |
| case kPrototypeInfo: |
| case kUninitialized: |
| case kMigrationTarget: |
| UNREACHABLE(); |
| return Tagged<Name>(); |
| case kWeakRef: { |
| Tagged<Map> map = Map::cast(raw_transitions_.GetHeapObjectAssumeWeak()); |
| return GetSimpleTransitionKey(map); |
| } |
| case kFullTransitionArray: |
| return transitions()->GetKey(transition_number); |
| } |
| UNREACHABLE(); |
| } |
| |
| void TransitionArray::SetKey(int transition_number, Tagged<Name> key) { |
| DCHECK(transition_number < number_of_transitions()); |
| WeakFixedArray::set(ToKeyIndex(transition_number), key); |
| } |
| |
| HeapObjectSlot TransitionArray::GetTargetSlot(int transition_number) { |
| DCHECK(transition_number < number_of_transitions()); |
| return HeapObjectSlot(RawFieldOfElementAt(ToTargetIndex(transition_number))); |
| } |
| |
| // static |
| PropertyDetails TransitionsAccessor::GetTargetDetails(Tagged<Name> name, |
| Tagged<Map> target) { |
| DCHECK(!IsSpecialTransition(name->GetReadOnlyRoots(), name)); |
| InternalIndex descriptor = target->LastAdded(); |
| Tagged<DescriptorArray> descriptors = |
| target->instance_descriptors(kRelaxedLoad); |
| // Transitions are allowed only for the last added property. |
| DCHECK(descriptors->GetKey(descriptor)->Equals(name)); |
| return descriptors->GetDetails(descriptor); |
| } |
| |
| PropertyDetails TransitionsAccessor::GetSimpleTargetDetails( |
| Tagged<Map> transition) { |
| return transition->GetLastDescriptorDetails(isolate_); |
| } |
| |
| // static |
| Tagged<Name> TransitionsAccessor::GetSimpleTransitionKey( |
| Tagged<Map> transition) { |
| InternalIndex descriptor = transition->LastAdded(); |
| return transition->instance_descriptors()->GetKey(descriptor); |
| } |
| |
| // static |
| Tagged<Map> TransitionsAccessor::GetTargetFromRaw(Tagged<MaybeObject> raw) { |
| return Map::cast(raw.GetHeapObjectAssumeWeak()); |
| } |
| |
| Tagged<MaybeObject> TransitionArray::GetRawTarget(int transition_number) { |
| DCHECK(transition_number < number_of_transitions()); |
| return get(ToTargetIndex(transition_number)); |
| } |
| |
| Tagged<Map> TransitionArray::GetTarget(int transition_number) { |
| Tagged<MaybeObject> raw = GetRawTarget(transition_number); |
| return TransitionsAccessor::GetTargetFromRaw(raw); |
| } |
| |
| Tagged<Map> TransitionsAccessor::GetTarget(int transition_number) { |
| switch (encoding()) { |
| case kPrototypeInfo: |
| case kUninitialized: |
| case kMigrationTarget: |
| UNREACHABLE(); |
| return Map(); |
| case kWeakRef: |
| return Map::cast(raw_transitions_.GetHeapObjectAssumeWeak()); |
| case kFullTransitionArray: |
| return transitions()->GetTarget(transition_number); |
| } |
| UNREACHABLE(); |
| } |
| |
| void TransitionArray::SetRawTarget(int transition_number, |
| Tagged<MaybeObject> value) { |
| DCHECK(transition_number < number_of_transitions()); |
| DCHECK(value.IsWeak()); |
| DCHECK(IsMap(value.GetHeapObjectAssumeWeak())); |
| WeakFixedArray::set(ToTargetIndex(transition_number), value); |
| } |
| |
| bool TransitionArray::GetTargetIfExists(int transition_number, Isolate* isolate, |
| Tagged<Map>* target) { |
| Tagged<MaybeObject> raw = GetRawTarget(transition_number); |
| Tagged<HeapObject> heap_object; |
| // If the raw target is a Smi, then this TransitionArray is in the process of |
| // being deserialized, and doesn't yet have an initialized entry for this |
| // transition. |
| if (raw.IsSmi()) { |
| DCHECK(isolate->has_active_deserializer()); |
| DCHECK_EQ(raw.ToSmi(), Smi::uninitialized_deserialization_value()); |
| return false; |
| } |
| if (raw.GetHeapObjectIfStrong(&heap_object) && |
| IsUndefined(heap_object, isolate)) { |
| return false; |
| } |
| *target = TransitionsAccessor::GetTargetFromRaw(raw); |
| return true; |
| } |
| |
| int TransitionArray::SearchNameForTesting(Tagged<Name> name, |
| int* out_insertion_index) { |
| return SearchName(name, out_insertion_index); |
| } |
| |
| Tagged<Map> TransitionArray::SearchAndGetTargetForTesting( |
| PropertyKind kind, Tagged<Name> name, PropertyAttributes attributes) { |
| return SearchAndGetTarget(kind, name, attributes); |
| } |
| |
| int TransitionArray::SearchSpecial(Tagged<Symbol> symbol, |
| bool concurrent_search, |
| int* out_insertion_index) { |
| return SearchName(symbol, concurrent_search, out_insertion_index); |
| } |
| |
| int TransitionArray::SearchName(Tagged<Name> name, bool concurrent_search, |
| int* out_insertion_index) { |
| DCHECK(IsUniqueName(name)); |
| return internal::Search<ALL_ENTRIES>(this, name, number_of_entries(), |
| out_insertion_index, concurrent_search); |
| } |
| |
| TransitionsAccessor::TransitionsAccessor(Isolate* isolate, Tagged<Map> map, |
| bool concurrent_access) |
| : isolate_(isolate), |
| map_(map), |
| raw_transitions_(map->raw_transitions(isolate_, kAcquireLoad)), |
| encoding_(GetEncoding(isolate_, raw_transitions_)), |
| concurrent_access_(concurrent_access) { |
| DCHECK_IMPLIES(encoding_ == kMigrationTarget, map_->is_deprecated()); |
| } |
| |
| int TransitionsAccessor::Capacity() { return transitions()->Capacity(); } |
| |
| // static |
| TransitionsAccessor::Encoding TransitionsAccessor::GetEncoding( |
| Isolate* isolate, Tagged<MaybeObject> raw_transitions) { |
| Tagged<HeapObject> heap_object; |
| if (raw_transitions.IsSmi() || raw_transitions.IsCleared()) { |
| return kUninitialized; |
| } else if (raw_transitions.IsWeak()) { |
| return kWeakRef; |
| } else if (raw_transitions.GetHeapObjectIfStrong(isolate, &heap_object)) { |
| if (IsTransitionArray(heap_object)) { |
| return kFullTransitionArray; |
| } else if (IsPrototypeInfo(heap_object)) { |
| return kPrototypeInfo; |
| } else { |
| DCHECK(IsMap(heap_object)); |
| return kMigrationTarget; |
| } |
| } else { |
| UNREACHABLE(); |
| } |
| } |
| |
| // static |
| TransitionsAccessor::Encoding TransitionsAccessor::GetEncoding( |
| Isolate* isolate, Tagged<TransitionArray> array) { |
| DCHECK_EQ(GetEncoding(isolate, Tagged<MaybeObject>(array)), |
| kFullTransitionArray); |
| return kFullTransitionArray; |
| } |
| |
| // static |
| TransitionsAccessor::Encoding TransitionsAccessor::GetEncoding( |
| Isolate* isolate, Handle<Map> map) { |
| Tagged<MaybeObject> raw_transitions = |
| map->raw_transitions(isolate, kAcquireLoad); |
| return GetEncoding(isolate, raw_transitions); |
| } |
| |
| // static |
| MaybeHandle<Map> TransitionsAccessor::SearchTransition( |
| Isolate* isolate, Handle<Map> map, Tagged<Name> name, PropertyKind kind, |
| PropertyAttributes attributes) { |
| Tagged<Map> result = TransitionsAccessor(isolate, *map) |
| .SearchTransition(name, kind, attributes); |
| if (result.is_null()) return MaybeHandle<Map>(); |
| return MaybeHandle<Map>(result, isolate); |
| } |
| |
| // static |
| MaybeHandle<Map> TransitionsAccessor::SearchSpecial(Isolate* isolate, |
| Handle<Map> map, |
| Tagged<Symbol> name) { |
| Tagged<Map> result = TransitionsAccessor(isolate, *map).SearchSpecial(name); |
| if (result.is_null()) return MaybeHandle<Map>(); |
| return MaybeHandle<Map>(result, isolate); |
| } |
| |
| int TransitionArray::number_of_transitions() const { |
| if (length() < kFirstIndex) return 0; |
| return get(kTransitionLengthIndex).ToSmi().value(); |
| } |
| |
| int TransitionArray::CompareKeys(Tagged<Name> key1, uint32_t hash1, |
| PropertyKind kind1, |
| PropertyAttributes attributes1, |
| Tagged<Name> key2, uint32_t hash2, |
| PropertyKind kind2, |
| PropertyAttributes attributes2) { |
| int cmp = CompareNames(key1, hash1, key2, hash2); |
| if (cmp != 0) return cmp; |
| |
| return CompareDetails(kind1, attributes1, kind2, attributes2); |
| } |
| |
| int TransitionArray::CompareNames(Tagged<Name> key1, uint32_t hash1, |
| Tagged<Name> key2, uint32_t hash2) { |
| if (key1 != key2) { |
| // In case of hash collisions key1 is always "less" than key2. |
| return hash1 <= hash2 ? -1 : 1; |
| } |
| |
| return 0; |
| } |
| |
| int TransitionArray::CompareDetails(PropertyKind kind1, |
| PropertyAttributes attributes1, |
| PropertyKind kind2, |
| PropertyAttributes attributes2) { |
| if (kind1 != kind2) { |
| return static_cast<int>(kind1) < static_cast<int>(kind2) ? -1 : 1; |
| } |
| |
| if (attributes1 != attributes2) { |
| return static_cast<int>(attributes1) < static_cast<int>(attributes2) ? -1 |
| : 1; |
| } |
| |
| return 0; |
| } |
| |
| void TransitionArray::Set(int transition_number, Tagged<Name> key, |
| Tagged<MaybeObject> target) { |
| WeakFixedArray::set(ToKeyIndex(transition_number), key); |
| WeakFixedArray::set(ToTargetIndex(transition_number), target); |
| } |
| |
| Tagged<Name> TransitionArray::GetSortedKey(int transition_number) { |
| return GetKey(transition_number); |
| } |
| |
| int TransitionArray::number_of_entries() const { |
| return number_of_transitions(); |
| } |
| |
| int TransitionArray::Capacity() { |
| if (length() <= kFirstIndex) return 0; |
| return (length() - kFirstIndex) / kEntrySize; |
| } |
| |
| void TransitionArray::SetNumberOfTransitions(int number_of_transitions) { |
| DCHECK(number_of_transitions <= Capacity()); |
| WeakFixedArray::set(kTransitionLengthIndex, |
| Smi::FromInt(number_of_transitions)); |
| } |
| |
| Handle<String> TransitionsAccessor::ExpectedTransitionKey() { |
| DisallowGarbageCollection no_gc; |
| switch (encoding()) { |
| case kPrototypeInfo: |
| case kUninitialized: |
| case kMigrationTarget: |
| case kFullTransitionArray: |
| return Handle<String>::null(); |
| case kWeakRef: { |
| Tagged<Map> target = |
| Map::cast(raw_transitions_.GetHeapObjectAssumeWeak()); |
| PropertyDetails details = GetSimpleTargetDetails(target); |
| if (details.location() != PropertyLocation::kField) |
| return Handle<String>::null(); |
| DCHECK_EQ(PropertyKind::kData, details.kind()); |
| if (details.attributes() != NONE) return Handle<String>::null(); |
| Tagged<Name> name = GetSimpleTransitionKey(target); |
| if (!IsString(name)) return Handle<String>::null(); |
| return handle(String::cast(name), isolate_); |
| } |
| } |
| UNREACHABLE(); |
| } |
| |
| Handle<Map> TransitionsAccessor::ExpectedTransitionTarget() { |
| DCHECK(!ExpectedTransitionKey().is_null()); |
| return handle(GetTarget(0), isolate_); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #include "src/objects/object-macros-undef.h" |
| |
| #endif // V8_OBJECTS_TRANSITIONS_INL_H_ |