| // Copyright 2018 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_JS_WEAK_REFS_H_ |
| #define V8_OBJECTS_JS_WEAK_REFS_H_ |
| |
| #include "src/objects/js-objects.h" |
| |
| // Has to be the last include (doesn't have include guards): |
| #include "src/objects/object-macros.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| class NativeContext; |
| class WeakCell; |
| |
| // FinalizationGroup object from the JS Weak Refs spec proposal: |
| // https://github.com/tc39/proposal-weakrefs |
| class JSFinalizationGroup : public JSObject { |
| public: |
| DECL_PRINTER(JSFinalizationGroup) |
| EXPORT_DECL_VERIFIER(JSFinalizationGroup) |
| DECL_CAST(JSFinalizationGroup) |
| |
| DECL_ACCESSORS(native_context, NativeContext) |
| DECL_ACCESSORS(cleanup, Object) |
| |
| DECL_ACCESSORS(active_cells, HeapObject) |
| DECL_ACCESSORS(cleared_cells, HeapObject) |
| DECL_ACCESSORS(key_map, Object) |
| |
| DECL_ACCESSORS(next_dirty, Object) |
| |
| DECL_INT_ACCESSORS(flags) |
| |
| class BodyDescriptor; |
| |
| inline static void Register(Handle<JSFinalizationGroup> finalization_group, |
| Handle<JSReceiver> target, |
| Handle<Object> holdings, Handle<Object> key, |
| Isolate* isolate); |
| inline static bool Unregister(Handle<JSFinalizationGroup> finalization_group, |
| Handle<JSReceiver> unregister_token, |
| Isolate* isolate); |
| |
| // RemoveUnregisterToken is called from both Unregister and during GC. Since |
| // it modifies slots in key_map and WeakCells and the normal write barrier is |
| // disabled during GC, we need to tell the GC about the modified slots via the |
| // gc_notify_updated_slot function. |
| template <typename MatchCallback, typename GCNotifyUpdatedSlotCallback> |
| inline bool RemoveUnregisterToken( |
| JSReceiver unregister_token, Isolate* isolate, |
| MatchCallback match_callback, |
| GCNotifyUpdatedSlotCallback gc_notify_updated_slot); |
| |
| // Returns true if the cleared_cells list is non-empty. |
| inline bool NeedsCleanup() const; |
| |
| inline bool scheduled_for_cleanup() const; |
| inline void set_scheduled_for_cleanup(bool scheduled_for_cleanup); |
| |
| // Remove the first cleared WeakCell from the cleared_cells |
| // list (assumes there is one) and return its holdings. |
| inline static Object PopClearedCellHoldings( |
| Handle<JSFinalizationGroup> finalization_group, Isolate* isolate); |
| |
| // Constructs an iterator for the WeakCells in the cleared_cells list and |
| // calls the user's cleanup function. |
| // |
| // Returns Nothing<bool> if exception occurs, otherwise returns Just(true). |
| static V8_WARN_UNUSED_RESULT Maybe<bool> Cleanup( |
| Isolate* isolate, Handle<JSFinalizationGroup> finalization_group, |
| Handle<Object> callback); |
| |
| // Layout description. |
| DEFINE_FIELD_OFFSET_CONSTANTS(JSObject::kHeaderSize, |
| TORQUE_GENERATED_JS_FINALIZATION_GROUP_FIELDS) |
| |
| // Bitfields in flags. |
| using ScheduledForCleanupField = base::BitField<bool, 0, 1>; |
| |
| OBJECT_CONSTRUCTORS(JSFinalizationGroup, JSObject); |
| }; |
| |
| // Internal object for storing weak references in JSFinalizationGroup. |
| class WeakCell : public TorqueGeneratedWeakCell<WeakCell, HeapObject> { |
| public: |
| DECL_PRINTER(WeakCell) |
| EXPORT_DECL_VERIFIER(WeakCell) |
| |
| class BodyDescriptor; |
| |
| // Nullify is called during GC and it modifies the pointers in WeakCell and |
| // JSFinalizationGroup. Thus we need to tell the GC about the modified slots |
| // via the gc_notify_updated_slot function. The normal write barrier is not |
| // enough, since it's disabled before GC. |
| template <typename GCNotifyUpdatedSlotCallback> |
| inline void Nullify(Isolate* isolate, |
| GCNotifyUpdatedSlotCallback gc_notify_updated_slot); |
| |
| inline void RemoveFromFinalizationGroupCells(Isolate* isolate); |
| |
| TQ_OBJECT_CONSTRUCTORS(WeakCell) |
| }; |
| |
| class JSWeakRef : public TorqueGeneratedJSWeakRef<JSWeakRef, JSObject> { |
| public: |
| DECL_PRINTER(JSWeakRef) |
| EXPORT_DECL_VERIFIER(JSWeakRef) |
| |
| class BodyDescriptor; |
| |
| TQ_OBJECT_CONSTRUCTORS(JSWeakRef) |
| }; |
| |
| class JSFinalizationGroupCleanupIterator |
| : public TorqueGeneratedJSFinalizationGroupCleanupIterator< |
| JSFinalizationGroupCleanupIterator, JSObject> { |
| public: |
| DECL_PRINTER(JSFinalizationGroupCleanupIterator) |
| DECL_VERIFIER(JSFinalizationGroupCleanupIterator) |
| |
| TQ_OBJECT_CONSTRUCTORS(JSFinalizationGroupCleanupIterator) |
| }; |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #include "src/objects/object-macros-undef.h" |
| |
| #endif // V8_OBJECTS_JS_WEAK_REFS_H_ |