Access old space marking bits from runtime only when incremental marking is in MARKING state.

src/objects-inl.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 2726 matching lines @@
 void DescriptorArray::SwapSortedKeys(int first, int second) {
   int first_key = GetSortedKeyIndex(first);
   SetSortedKey(first, GetSortedKeyIndex(second));
   SetSortedKey(second, first_key);
 }
 
 
 DescriptorArray::WhitenessWitness::WhitenessWitness(FixedArray* array)
     : marking_(array->GetHeap()->incremental_marking()) {
   marking_->EnterNoMarkingScope();
-  ASSERT(Marking::Color(array) == Marking::WHITE_OBJECT);
+  ASSERT(!marking_->IsMarking() ||
+         Marking::Color(array) == Marking::WHITE_OBJECT);
 }
 
 
 DescriptorArray::WhitenessWitness::~WhitenessWitness() {
   marking_->LeaveNoMarkingScope();
 }
 
 
 template<typename Shape, typename Key>
 int HashTable<Shape, Key>::ComputeCapacity(int at_least_space_for) {
@@ skipping 4006 matching lines @@
 #undef READ_UINT32_FIELD
 #undef WRITE_UINT32_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_