LoadUint32() doesn't need a scratch register.

src/ia32/macro-assembler-ia32.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_IA32_MACRO_ASSEMBLER_IA32_H_
 #define V8_IA32_MACRO_ASSEMBLER_IA32_H_
 
 #include "assembler.h"
 #include "frames.h"
 #include "v8globals.h"
@@ skipping 447 matching lines @@
   }
 
   // Modifies the register even if it does not contain a Smi!
   void SmiUntag(Register reg, Label* is_smi) {
     STATIC_ASSERT(kSmiTagSize == 1);
     sar(reg, kSmiTagSize);
     STATIC_ASSERT(kSmiTag == 0);
     j(not_carry, is_smi);
   }
 
-  void LoadUint32(XMMRegister dst, Register src, XMMRegister scratch);
+  void LoadUint32(XMMRegister dst, Register src);
 
   // Jump the register contains a smi.
   inline void JumpIfSmi(Register value,
                         Label* smi_label,
                         Label::Distance distance = Label::kFar) {
     test(value, Immediate(kSmiTagMask));
     j(zero, smi_label, distance);
   }
   // Jump if the operand is a smi.
   inline void JumpIfSmi(Operand value,
@@ skipping 604 matching lines @@
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_MACRO_ASSEMBLER_IA32_H_