Extending map verification to also verify LastAdded/DescriptorArray consistency.

src/objects-debug.cc

 // 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 284 matching lines @@
 
 
 void Map::MapVerify() {
   ASSERT(!HEAP->InNewSpace(this));
   ASSERT(FIRST_TYPE <= instance_type() && instance_type() <= LAST_TYPE);
   ASSERT(instance_size() == kVariableSizeSentinel ||
          (kPointerSize <= instance_size() &&
           instance_size() < HEAP->Capacity()));
   VerifyHeapPointer(prototype());
   VerifyHeapPointer(instance_descriptors());
+  if (instance_descriptors()->number_of_descriptors() == 0) {
+    ASSERT(LastAdded() == kNoneAdded);
+  } else {
+    ASSERT(instance_descriptors()->GetDetails(LastAdded()).index() ==
+           instance_descriptors()->number_of_descriptors());
+  }
   SLOW_ASSERT(instance_descriptors()->IsSortedNoDuplicates());
   if (HasTransitionArray()) {
     SLOW_ASSERT(transitions()->IsSortedNoDuplicates());
     SLOW_ASSERT(transitions()->IsConsistentWithBackPointers(this));
   }
 }
 
 
 void Map::SharedMapVerify() {
   MapVerify();
@@ skipping 693 matching lines @@
   FixedArray* proto_transitions = GetPrototypeTransitions();
   MemsetPointer(proto_transitions->data_start(),
                 GetHeap()->the_hole_value(),
                 proto_transitions->length());
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal