| // 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" |
| #include "src/objects/microtask.h" |
| |
| // Has to be the last include (doesn't have include guards): |
| #include "src/objects/object-macros.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| class JSWeakCell; |
| |
| // WeakFactory object from the JS Weak Refs spec proposal: |
| // https://github.com/tc39/proposal-weakrefs |
| class JSWeakFactory : public JSObject { |
| public: |
| DECL_PRINTER(JSWeakFactory) |
| DECL_VERIFIER(JSWeakFactory) |
| DECL_CAST2(JSWeakFactory) |
| |
| DECL_ACCESSORS2(native_context, Context) |
| DECL_ACCESSORS(cleanup, Object) |
| DECL_ACCESSORS(active_cells, Object) |
| DECL_ACCESSORS(cleared_cells, Object) |
| |
| // For storing a list of JSWeakFactory objects in NativeContext. |
| DECL_ACCESSORS(next, Object) |
| |
| DECL_INT_ACCESSORS(flags) |
| |
| // Adds a newly constructed JSWeakCell object into this JSWeakFactory. |
| inline void AddWeakCell(JSWeakCell weak_cell); |
| |
| // 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); |
| |
| // Get and remove the first cleared JSWeakCell from the cleared_cells |
| // list. (Assumes there is one.) |
| inline JSWeakCell PopClearedCell(Isolate* isolate); |
| |
| // Constructs an iterator for the WeakCells in the cleared_cells list and |
| // calls the user's cleanup function. |
| static void Cleanup(Handle<JSWeakFactory> weak_factory, Isolate* isolate); |
| |
| // Layout description. |
| #define JS_WEAK_FACTORY_FIELDS(V) \ |
| V(kNativeContextOffset, kTaggedSize) \ |
| V(kCleanupOffset, kTaggedSize) \ |
| V(kActiveCellsOffset, kTaggedSize) \ |
| V(kClearedCellsOffset, kTaggedSize) \ |
| V(kNextOffset, kTaggedSize) \ |
| V(kFlagsOffset, kTaggedSize) \ |
| /* Header size. */ \ |
| V(kSize, 0) |
| |
| DEFINE_FIELD_OFFSET_CONSTANTS(JSObject::kHeaderSize, JS_WEAK_FACTORY_FIELDS) |
| #undef JS_WEAK_FACTORY_FIELDS |
| |
| // Bitfields in flags. |
| class ScheduledForCleanupField : public BitField<bool, 0, 1> {}; |
| |
| OBJECT_CONSTRUCTORS(JSWeakFactory, JSObject); |
| }; |
| |
| // WeakCell object from the JS Weak Refs spec proposal. |
| class JSWeakCell : public JSObject { |
| public: |
| DECL_PRINTER(JSWeakCell) |
| DECL_VERIFIER(JSWeakCell) |
| DECL_CAST2(JSWeakCell) |
| |
| DECL_ACCESSORS(factory, Object) |
| DECL_ACCESSORS(target, Object) |
| DECL_ACCESSORS(holdings, Object) |
| |
| // For storing doubly linked lists of JSWeakCells in JSWeakFactory. |
| DECL_ACCESSORS(prev, Object) |
| DECL_ACCESSORS(next, Object) |
| |
| // Layout description. |
| #define JS_WEAK_CELL_FIELDS(V) \ |
| V(kFactoryOffset, kTaggedSize) \ |
| V(kTargetOffset, kTaggedSize) \ |
| V(kHoldingsOffset, kTaggedSize) \ |
| V(kPrevOffset, kTaggedSize) \ |
| V(kNextOffset, kTaggedSize) \ |
| /* Header size. */ \ |
| V(kSize, 0) |
| |
| DEFINE_FIELD_OFFSET_CONSTANTS(JSObject::kHeaderSize, JS_WEAK_CELL_FIELDS) |
| #undef JS_WEAK_CELL_FIELDS |
| |
| class BodyDescriptor; |
| |
| // Nullify is called during GC and it modifies the pointers in JSWeakCell and |
| // JSWeakFactory. 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. |
| inline void Nullify( |
| Isolate* isolate, |
| std::function<void(HeapObject* object, ObjectSlot slot, Object* target)> |
| gc_notify_updated_slot); |
| |
| inline void Clear(Isolate* isolate); |
| |
| OBJECT_CONSTRUCTORS(JSWeakCell, JSObject); |
| }; |
| |
| class JSWeakRef : public JSWeakCell { |
| public: |
| DECL_CAST2(JSWeakRef) |
| OBJECT_CONSTRUCTORS(JSWeakRef, JSWeakCell); |
| }; |
| |
| class WeakFactoryCleanupJobTask : public Microtask { |
| public: |
| DECL_ACCESSORS2(factory, JSWeakFactory) |
| |
| DECL_CAST(WeakFactoryCleanupJobTask) |
| DECL_VERIFIER(WeakFactoryCleanupJobTask) |
| DECL_PRINTER(WeakFactoryCleanupJobTask) |
| |
| // Layout description. |
| #define WEAK_FACTORY_CLEANUP_JOB_TASK_FIELDS(V) \ |
| V(kFactoryOffset, kTaggedSize) \ |
| /* Total size. */ \ |
| V(kSize, 0) |
| |
| DEFINE_FIELD_OFFSET_CONSTANTS(Microtask::kHeaderSize, |
| WEAK_FACTORY_CLEANUP_JOB_TASK_FIELDS) |
| #undef WEAK_FACTORY_CLEANUP_JOB_TASK_FIELDS |
| |
| private: |
| DISALLOW_IMPLICIT_CONSTRUCTORS(WeakFactoryCleanupJobTask); |
| }; |
| |
| class JSWeakFactoryCleanupIterator : public JSObject { |
| public: |
| DECL_PRINTER(JSWeakFactoryCleanupIterator) |
| DECL_VERIFIER(JSWeakFactoryCleanupIterator) |
| DECL_CAST2(JSWeakFactoryCleanupIterator) |
| |
| DECL_ACCESSORS2(factory, JSWeakFactory) |
| |
| // Layout description. |
| #define JS_WEAK_FACTORY_CLEANUP_ITERATOR_FIELDS(V) \ |
| V(kFactoryOffset, kTaggedSize) \ |
| /* Header size. */ \ |
| V(kSize, 0) |
| |
| DEFINE_FIELD_OFFSET_CONSTANTS(JSObject::kHeaderSize, |
| JS_WEAK_FACTORY_CLEANUP_ITERATOR_FIELDS) |
| #undef JS_WEAK_FACTORY_CLEANUP_ITERATOR_FIELDS |
| |
| OBJECT_CONSTRUCTORS(JSWeakFactoryCleanupIterator, JSObject); |
| }; |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #include "src/objects/object-macros-undef.h" |
| |
| #endif // V8_OBJECTS_JS_WEAK_REFS_H_ |