Tag stubs that rely on instance types as MEGAMORPHIC.

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 530 matching lines @@
   virtual int MinorKey() { return exponent_type_; }
 
   ExponentType exponent_type_;
 };
 
 
 class ICStub: public PlatformCodeStub {
  public:
   explicit ICStub(Code::Kind kind) : kind_(kind) { }
   virtual int GetCodeKind() { return kind_; }
-  virtual InlineCacheState GetICState() { return MONOMORPHIC; }
+  // Currently all IC stubs do not collect explicit type feedback but rather
+  // check the instance type.
+  // TODO(verwaest): These stubs should collect proper type feedback, and should
+  // not check the instance type explicitly (perhaps unless more than
+  // kMaxPolymorphism maps are recorded).
+  virtual InlineCacheState GetICState() { return MEGAMORPHIC; }
 
   bool Describes(Code* code) {
     return GetMajorKey(code) == MajorKey() && code->stub_info() == MinorKey();
   }
 
  protected:
   class KindBits: public BitField<Code::Kind, 0, 4> {};
   virtual void FinishCode(Handle<Code> code) {
     code->set_stub_info(MinorKey());
   }
@@ skipping 863 matching lines @@
 
   // The current function entry hook.
   static FunctionEntryHook entry_hook_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileEntryHookStub);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_