ES6: Implement WeakSet

src/mark-compact.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 677 matching lines @@
 
   INLINE(void RecordSlot(Object** anchor_slot, Object** slot, Object* object));
 
   void MigrateObject(Address dst,
                      Address src,
                      int size,
                      AllocationSpace to_old_space);
 
   bool TryPromoteObject(HeapObject* object, int object_size);
 
-  inline Object* encountered_weak_maps() { return encountered_weak_maps_; }
-  inline void set_encountered_weak_maps(Object* weak_map) {
-    encountered_weak_maps_ = weak_map;
+  inline Object* encountered_weak_collections() {
+    return encountered_weak_collections_;
+  }
+  inline void set_encountered_weak_collections(Object* weak_collection) {
+    encountered_weak_collections_ = weak_collection;
   }
 
   void InvalidateCode(Code* code);
 
   void ClearMarkbits();
 
   bool abort_incremental_marking() const { return abort_incremental_marking_; }
 
   bool is_compacting() const { return compacting_; }
 
@@ skipping 175 matching lines @@
 
   void ClearAndDeoptimizeDependentCode(Map* map);
   void ClearNonLiveDependentCode(DependentCode* dependent_code);
 
   // Marking detaches initial maps from SharedFunctionInfo objects
   // to make this reference weak. We need to reattach initial maps
   // back after collection. This is either done during
   // ClearNonLiveTransitions pass or by calling this function.
   void ReattachInitialMaps();
 
-  // Mark all values associated with reachable keys in weak maps encountered
-  // so far.  This might push new object or even new weak maps onto the
-  // marking stack.
-  void ProcessWeakMaps();
+  // Mark all values associated with reachable keys in weak collections
+  // encountered so far.  This might push new object or even new weak maps onto
+  // the marking stack.
+  void ProcessWeakCollections();
 
   // After all reachable objects have been marked those weak map entries
   // with an unreachable key are removed from all encountered weak maps.
   // The linked list of all encountered weak maps is destroyed.
-  void ClearWeakMaps();
+  void ClearWeakCollections();
 
   // -----------------------------------------------------------------------
   // Phase 2: Sweeping to clear mark bits and free non-live objects for
   // a non-compacting collection.
   //
   //  Before: Live objects are marked and non-live objects are unmarked.
   //
   //   After: Live objects are unmarked, non-live regions have been added to
   //          their space's free list. Active eden semispace is compacted by
   //          evacuation.
@@ skipping 21 matching lines @@
   friend class MarkObjectVisitor;
   static void VisitObject(HeapObject* obj);
 
   friend class UnmarkObjectVisitor;
   static void UnmarkObject(HeapObject* obj);
 #endif
 
   Heap* heap_;
   MarkingDeque marking_deque_;
   CodeFlusher* code_flusher_;
-  Object* encountered_weak_maps_;
+  Object* encountered_weak_collections_;
 
   List<Page*> evacuation_candidates_;
   List<Code*> invalidated_code_;
 
   friend class Heap;
 };
 
 
 class MarkBitCellIterator BASE_EMBEDDED {
  public:
@@ skipping 53 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 
 } }  // namespace v8::internal
 
 #endif  // V8_MARK_COMPACT_H_