Fix PathTracer.

src/objects-inl.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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 1310 matching lines @@
   return heap;
 }
 
 
 Isolate* HeapObject::GetIsolate() {
   return GetHeap()->isolate();
 }
 
 
 Map* HeapObject::map() {
+#ifdef DEBUG
+  // Clear mark potentially added by PathTracer.
+  uintptr_t raw_value =
+      map_word().ToRawValue() & ~static_cast<uintptr_t>(PathTracer::kMarkTag);
+  return MapWord::FromRawValue(raw_value).ToMap();
+#else
   return map_word().ToMap();
+#endif
 }
 
 
 void HeapObject::set_map(Map* value) {
   set_map_word(MapWord::FromMap(value));
   if (value != NULL) {
     // TODO(1600) We are passing NULL as a slot because maps can never be on
     // evacuation candidate.
     value->GetHeap()->incremental_marking()->RecordWrite(this, NULL, value);
   }
@@ skipping 5495 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_