Eliminate special keyed load string stub in favor of uniform handlers.

src/ic/ic.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_IC_H_
 #define V8_IC_H_
 
 #include "src/ic/ic-state.h"
 #include "src/macro-assembler.h"
 
@@ skipping 394 matching lines @@
                                            Handle<Object> key);
 
   // Code generator routines.
   static void GenerateMiss(MacroAssembler* masm);
   static void GenerateRuntimeGetProperty(MacroAssembler* masm);
   static void GenerateInitialize(MacroAssembler* masm) { GenerateMiss(masm); }
   static void GeneratePreMonomorphic(MacroAssembler* masm) {
     GenerateMiss(masm);
   }
   static void GenerateGeneric(MacroAssembler* masm);
-  static void GenerateString(MacroAssembler* masm);
 
   // Bit mask to be tested against bit field for the cases when
   // generic stub should go into slow case.
   // Access check is necessary explicitly since generic stub does not perform
   // map checks.
   static const int kSlowCaseBitFieldMask =
       (1 << Map::kIsAccessCheckNeeded) | (1 << Map::kHasIndexedInterceptor);
 
   static Handle<Code> generic_stub(Isolate* isolate);
   static Handle<Code> pre_monomorphic_stub(Isolate* isolate);
 
  protected:
-  Handle<Code> LoadElementStub(Handle<JSObject> receiver);
+  // receiver is HeapObject because it could be a String or a JSObject
+  Handle<Code> LoadElementStub(Handle<HeapObject> receiver);
   virtual Handle<Code> pre_monomorphic_stub() const {
     return pre_monomorphic_stub(isolate());
   }
 
  private:
   Handle<Code> generic_stub() const { return generic_stub(isolate()); }
-  Handle<Code> string_stub() {
-    return isolate()->builtins()->KeyedLoadIC_String();
-  }
 
   static void Clear(Isolate* isolate, Address address, Code* target,
                     ConstantPoolArray* constant_pool);
 
   friend class IC;
 };
 
 
 class StoreIC : public IC {
  public:
@@ skipping 240 matching lines @@
 
 // Support functions for interceptor handlers.
 DECLARE_RUNTIME_FUNCTION(LoadPropertyWithInterceptorOnly);
 DECLARE_RUNTIME_FUNCTION(LoadPropertyWithInterceptor);
 DECLARE_RUNTIME_FUNCTION(LoadElementWithInterceptor);
 DECLARE_RUNTIME_FUNCTION(StorePropertyWithInterceptor);
 }
 }  // namespace v8::internal
 
 #endif  // V8_IC_H_