ia32 StringAddStub: fast two character case.

src/ia32/macro-assembler-ia32.h

 // Copyright 2006-2009 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 338 matching lines @@
                              Register scratch1,
                              Register scratch2,
                              Register scratch3,
                              Label* gc_required);
   void AllocateAsciiString(Register result,
                            Register length,
                            Register scratch1,
                            Register scratch2,
                            Register scratch3,
                            Label* gc_required);
+  void AllocateAsciiString(Register result,
+                           int length,
+                           Register scratch,
+                           Label* gc_required);
 
   // Allocate a raw cons string object. Only the map field of the result is
   // initialized.
   void AllocateConsString(Register result,
                           Register scratch1,
                           Register scratch2,
                           Label* gc_required);
   void AllocateAsciiConsString(Register result,
                                Register scratch1,
                                Register scratch2,
@@ skipping 279 matching lines @@
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_MACRO_ASSEMBLER_IA32_H_