Switch UnreachableObjectsFilter to use Marking instead of InstrusiveMarking.

src/mark-compact.h

 // Copyright 2011 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 520 matching lines @@
 
   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;
   }
 
   void InvalidateCode(Code* code);
 
+  void ClearMarkbits();
+
+  void TaintMarkbits() {

[Erik Corry, 2011/10/19 17:56:07]

I think it would be preferable with a SetTaintMarkbits(bool value)

+    markbits_are_tainted_ = true;
+  }
+
+  bool AreMarkbitsTainted() {
+    return markbits_are_tainted_;
+  }
+
+  static inline bool IsLiveBytesUpdateRequired(HeapObject* obj);
+
  private:
   MarkCompactCollector();
   ~MarkCompactCollector();
 
   bool MarkInvalidatedCode();
   void RemoveDeadInvalidatedCode();
   void ProcessInvalidatedCode(ObjectVisitor* visitor);
 
 
 #ifdef DEBUG
@@ skipping 16 matching lines @@
   bool sweep_precisely_;
 
   // True if we are collecting slots to perform evacuation from evacuation
   // candidates.
   bool compacting_;
 
   bool was_marked_incrementally_;
 
   bool collect_maps_;
 
+  bool markbits_are_tainted_;
+
   // A pointer to the current stack-allocated GC tracer object during a full
   // collection (NULL before and after).
   GCTracer* tracer_;
 
   SlotsBufferAllocator slots_buffer_allocator_;
 
   SlotsBuffer* migration_slots_buffer_;
 
   // Finishes GC, performs heap verification if enabled.
   void Finish();
@@ skipping 123 matching lines @@
   void EvacuateNewSpace();
 
   void EvacuateLiveObjectsFromPage(Page* p);
 
   void EvacuatePages();
 
   void EvacuateNewSpaceAndCandidates();
 
   void SweepSpace(PagedSpace* space, SweeperType sweeper);
 
-
 #ifdef DEBUG
   // -----------------------------------------------------------------------
   // Debugging variables, functions and classes
   // Counters used for debugging the marking phase of mark-compact or
   // mark-sweep collection.
 
   // Size of live objects in Heap::to_space_.
   int live_young_objects_size_;
 
   // Size of live objects in Heap::old_pointer_space_.
@@ skipping 34 matching lines @@
 
   friend class Heap;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 
 } }  // namespace v8::internal
 
 #endif  // V8_MARK_COMPACT_H_