Improve ClampDoubleToUint8 on ia32/x64

src/x64/macro-assembler-x64.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 924 matching lines @@
 
   // FCmp compares and pops the two values on top of the FPU stack.
   // The flag results are similar to integer cmp, but requires unsigned
   // jcc instructions (je, ja, jae, jb, jbe, je, and jz).
   void FCmp();
 
   void ClampUint8(Register reg);
 
   void ClampDoubleToUint8(XMMRegister input_reg,
                           XMMRegister temp_xmm_reg,
-                          Register result_reg,
-                          Register temp_reg);
+                          Register result_reg);
 
   void LoadUint32(XMMRegister dst, Register src, XMMRegister scratch);
 
   void LoadInstanceDescriptors(Register map, Register descriptors);
   void EnumLength(Register dst, Register map);
   void NumberOfOwnDescriptors(Register dst, Register map);
 
   template<typename Field>
   void DecodeField(Register reg) {
     static const int shift = Field::kShift + kSmiShift;
@@ skipping 540 matching lines @@
     masm->popfd();                                                        \
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_