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

src/code-stubs.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 1183 matching lines @@
 class BinaryOpICWithAllocationSiteStub V8_FINAL : public PlatformCodeStub {
  public:
   explicit BinaryOpICWithAllocationSiteStub(const BinaryOpIC::State& state)
       : state_(state) {}
 
   static void GenerateAheadOfTime(Isolate* isolate);
 
   Handle<Code> GetCodeCopyFromTemplate(Isolate* isolate,
                                        Handle<AllocationSite> allocation_site) {
     Code::FindAndReplacePattern pattern;
-    pattern.Add(isolate->factory()->oddball_map(), allocation_site);
+    pattern.Add(isolate->factory()->undefined_map(), allocation_site);
     return CodeStub::GetCodeCopy(isolate, pattern);
   }
 
   virtual Code::Kind GetCodeKind() const V8_OVERRIDE {
     return Code::BINARY_OP_IC;
   }
 
   virtual InlineCacheState GetICState() V8_OVERRIDE {
     return state_.GetICState();
   }
@@ skipping 1309 matching lines @@
 
 
 class CallDescriptors {
  public:
   static void InitializeForIsolate(Isolate* isolate);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_