Make objects embedded in optimized code weak.

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 619 matching lines @@
 
   enum SweepingParallelism {
     SWEEP_SEQUENTIALLY,
     SWEEP_IN_PARALLEL
   };
 
 #ifdef VERIFY_HEAP
   void VerifyMarkbitsAreClean();
   static void VerifyMarkbitsAreClean(PagedSpace* space);
   static void VerifyMarkbitsAreClean(NewSpace* space);
-  void VerifyWeakEmbeddedMapsInOptimizedCode();
+  void VerifyWeakEmbeddedObjectsInOptimizedCode();
   void VerifyOmittedMapChecks();
 #endif
 
   // Sweep a single page from the given space conservatively.
   // Return a number of reclaimed bytes.
   template<SweepingParallelism type>
   static intptr_t SweepConservatively(PagedSpace* space,
                                       FreeList* free_list,
                                       Page* p);
 
@@ skipping 77 matching lines @@
   bool IsConcurrentSweepingInProgress();
 
   void set_sequential_sweeping(bool sequential_sweeping) {
     sequential_sweeping_ = sequential_sweeping;
   }
 
   bool sequential_sweeping() const {
     return sequential_sweeping_;
   }
 
+  // Mark the global table which maps weak objects to dependent code without
+  // marking its contents.
+  void MarkWeakObjectToCodeTable();
+
  private:
   MarkCompactCollector();
   ~MarkCompactCollector();
 
   bool MarkInvalidatedCode();
   bool WillBeDeoptimized(Code* code);
   void RemoveDeadInvalidatedCode();
   void ProcessInvalidatedCode(ObjectVisitor* visitor);
 
   void UnlinkEvacuationCandidates();
@@ skipping 129 matching lines @@
   // heap object.
   static bool IsUnmarkedHeapObject(Object** p);
   static bool IsUnmarkedHeapObjectWithHeap(Heap* heap, Object** p);
 
   // 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 ClearAndDeoptimizeDependentCode(Map* map);
+  void ClearAndDeoptimizeDependentCode(DependentCode* dependent_code);
   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 collections
   // encountered so far.  This might push new object or even new weak maps onto
@@ skipping 113 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 
 } }  // namespace v8::internal
 
 #endif  // V8_MARK_COMPACT_H_