Avoid using double temp register explicitly in lithium codegen

src/ia32/lithium-codegen-ia32.cc

 // 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 5714 matching lines @@
   Register value_reg = ToRegister(instr->result());
   __ ClampUint8(value_reg);
 }
 
 
 void LCodeGen::DoClampTToUint8(LClampTToUint8* instr) {
   CpuFeatureScope scope(masm(), SSE2);
 
   ASSERT(instr->unclamped()->Equals(instr->result()));
   Register input_reg = ToRegister(instr->unclamped());
+  XMMRegister temp_xmm_reg = ToDoubleRegister(instr->temp_xmm());
   XMMRegister xmm_scratch = double_scratch0();
   Label is_smi, done, heap_number;
 
   __ JumpIfSmi(input_reg, &is_smi);
 
   // Check for heap number
   __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
          factory()->heap_number_map());
   __ j(equal, &heap_number, Label::kNear);
 
   // Check for undefined. Undefined is converted to zero for clamping
   // conversions.
   __ cmp(input_reg, factory()->undefined_value());
   DeoptimizeIf(not_equal, instr->environment());
   __ mov(input_reg, 0);
   __ jmp(&done, Label::kNear);
 
   // Heap number
   __ bind(&heap_number);
   __ movdbl(xmm_scratch, FieldOperand(input_reg, HeapNumber::kValueOffset));
-  __ ClampDoubleToUint8(xmm_scratch, xmm1, input_reg);
+  __ ClampDoubleToUint8(xmm_scratch, temp_xmm_reg, input_reg);
   __ jmp(&done, Label::kNear);
 
   // smi
   __ bind(&is_smi);
   __ SmiUntag(input_reg);
   __ ClampUint8(input_reg);
   __ bind(&done);
 }
 
 
@@ skipping 628 matching lines @@
                               FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32