Use distinct maps for oddballs with special handling in the type system.

src/ic.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 674 matching lines @@
 Handle<HeapType> IC::CurrentTypeOf(Handle<Object> object, Isolate* isolate) {
   return object->IsJSGlobalObject()
       ? HeapType::Constant(Handle<JSGlobalObject>::cast(object), isolate)
       : HeapType::NowOf(object, isolate);
 }
 
 
 Handle<Map> IC::TypeToMap(HeapType* type, Isolate* isolate) {
   if (type->Is(HeapType::Number()))
     return isolate->factory()->heap_number_map();
-  if (type->Is(HeapType::Boolean())) return isolate->factory()->oddball_map();
+  if (type->Is(HeapType::Boolean())) return isolate->factory()->boolean_map();
   if (type->IsConstant()) {
     return handle(Handle<JSGlobalObject>::cast(type->AsConstant())->map());
   }
   ASSERT(type->IsClass());
   return type->AsClass();
 }
 
 
 template <class T>
 typename T::TypeHandle IC::MapToType(Handle<Map> map,
@@ skipping 2131 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal