Prevent modification of cached normalized maps....

src/objects-debug.cc

 // Copyright 2006-2008 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 631 matching lines @@
   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());
 }
 
 
-void Map::NormalizedMapVerify() {
+void Map::SharedMapVerify() {
   MapVerify();
+  ASSERT(is_shared());
   ASSERT_EQ(Heap::empty_descriptor_array(), instance_descriptors());
   ASSERT_EQ(Heap::empty_fixed_array(), code_cache());
   ASSERT_EQ(0, pre_allocated_property_fields());
   ASSERT_EQ(0, unused_property_fields());
   ASSERT_EQ(StaticVisitorBase::GetVisitorId(instance_type(), instance_size()),
       visitor_id());
 }
 
 
 void CodeCache::CodeCachePrint() {
@@ skipping 710 matching lines @@
   }
 }
 
 
 void NormalizedMapCache::NormalizedMapCacheVerify() {
   FixedArray::cast(this)->Verify();
   if (FLAG_enable_slow_asserts) {
     for (int i = 0; i < length(); i++) {
       Object* e = get(i);
       if (e->IsMap()) {
-        Map::cast(e)->NormalizedMapVerify();
+        Map::cast(e)->SharedMapVerify();
       } else {
         ASSERT(e->IsUndefined());
       }
     }
   }
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal