Implement map collection for incremental marking.

src/incremental-marking-inl.h

-// Copyright 2011 the V8 project authors. All rights reserved.
+// 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
 //       with the distribution.
@@ skipping 99 matching lines @@
       }
       allocation_marking_factor_ = kMaxAllocationMarkingFactor;
     }
   }
 
   marking_deque_.UnshiftGrey(obj);
 }
 
 
 void IncrementalMarking::WhiteToGreyAndPush(HeapObject* obj, MarkBit mark_bit) {
-  WhiteToGrey(obj, mark_bit);
+  Marking::WhiteToGrey(mark_bit);
   marking_deque_.PushGrey(obj);
 }
 
 
-void IncrementalMarking::WhiteToGrey(HeapObject* obj, MarkBit mark_bit) {
-  Marking::WhiteToGrey(mark_bit);
+bool IncrementalMarking::MarkObjectAndPush(HeapObject* obj) {
+  MarkBit mark_bit = Marking::MarkBitFrom(obj);
+  if (!mark_bit.Get()) {
+    WhiteToGreyAndPush(obj, mark_bit);
+    return true;
+  }
+  return false;
 }
 
 
+bool IncrementalMarking::MarkObjectWithoutPush(HeapObject* obj) {
+  MarkBit mark_bit = Marking::MarkBitFrom(obj);
+  if (!mark_bit.Get()) {
+    mark_bit.Set();
+    MemoryChunk::IncrementLiveBytesFromGC(obj->address(), obj->Size());
+    return true;
+  }
+  return false;
+}
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_INCREMENTAL_MARKING_INL_H_