Use weak cells in dependent code.

src/heap/mark-compact.h

 // 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_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include "src/base/bits.h"
 #include "src/heap/spaces.h"
 
@@ skipping 635 matching lines @@
 
   // Checks if sweeping is in progress right now on any space.
   bool sweeping_in_progress() { return sweeping_in_progress_; }
 
   void set_evacuation(bool evacuation) { evacuation_ = evacuation; }
 
   bool evacuation() const { return evacuation_; }
 
   // Mark the global table which maps weak objects to dependent code without
   // marking its contents.
-  void MarkWeakObjectToCodeTable();
+  void MarkWeakObjectToCodeTable(ObjectVisitor* visitor);
 
   // Special case for processing weak references in a full collection. We need
   // to artificially keep AllocationSites alive for a time.
   void MarkAllocationSite(AllocationSite* site);
 
   MarkingDeque* marking_deque() { return &marking_deque_; }
 
   void EnsureMarkingDequeIsCommittedAndInitialize();
 
   void InitializeMarkingDeque();
@@ skipping 136 matching lines @@
   // Map transitions from a live map to a dead map must be killed.
   // We replace them with a null descriptor, with the same key.
   void ClearNonLiveReferences();
   void ClearNonLivePrototypeTransitions(Map* map);
   void ClearNonLiveMapTransitions(Map* map, MarkBit map_mark);
   void ClearMapTransitions(Map* map);
   bool ClearMapBackPointer(Map* map);
   void TrimDescriptorArray(Map* map, DescriptorArray* descriptors,
                            int number_of_own_descriptors);
   void TrimEnumCache(Map* map, DescriptorArray* descriptors);
 

[Hannes Payer (out of office), 2015/01/29 21:28:36]

Please remove the definitions below.

   void ClearDependentCode(DependentCode* dependent_code);
   void ClearNonLiveDependentCode(DependentCode* dependent_code);
   int ClearNonLiveDependentCodeInGroup(DependentCode* dependent_code, int group,
                                        int start, int end, int new_start);
 
   // 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();
 
@@ skipping 132 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_MARK_COMPACT_H_