Parallelize marking phase of mark-sweep/compact collection cycle.

src/objects.h

 // Copyright 2010 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 1025 matching lines @@
   // Given a heap object's map pointer, returns the heap size in bytes
   // Useful when the map pointer field is used for other purposes.
   // GC internal.
   inline int SizeFromMap(Map* map);
 
   // Support for the marking heap objects during the marking phase of GC.
   // True if the object is marked live.
   inline bool IsMarked();
 
   // Mutate this object's map pointer to indicate that the object is live.
-  inline void SetMark();
+  inline bool SetMark();
+
+  // Mutate this object's map pointer to indicate that the object is live.
+  inline bool SetMarkExclusively();
+
 
   // Mutate this object's map pointer to remove the indication that the
   // object is live (ie, partially restore the map pointer).
   inline void ClearMark();
 
   // True if this object is marked as overflowed.  Overflowed objects have
   // been reached and marked during marking of the heap, but their children
   // have not necessarily been marked and they have not been pushed on the
   // marking stack.
   inline bool IsOverflowed();
@@ skipping 1945 matching lines @@
 
   // Casting.
   static inline Code* cast(Object* obj);
 
   // Dispatched behavior.
   int CodeSize() { return SizeFor(body_size()); }
   inline void CodeIterateBody(ObjectVisitor* v);
 
   template<typename StaticVisitor>
   inline void CodeIterateBody();
+
+  template<typename StaticVisitor, typename Data>
+  inline void CodeIterateBody(Data data);
 #ifdef DEBUG
   void CodePrint();
   void CodeVerify();
 #endif
   // Layout description.
   static const int kInstructionSizeOffset = HeapObject::kHeaderSize;
   static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize;
   static const int kFlagsOffset = kRelocationInfoOffset + kPointerSize;
   static const int kKindSpecificFlagsOffset  = kFlagsOffset + kIntSize;
   // Add padding to align the instruction start following right after
@@ skipping 2700 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_