LoadUint32() doesn't need a scratch register.

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 6c13443b4e2375da6b4e52c658a112d4d9213850..58290759987e45cc3fdff4e7f8a4ca99c04c115e 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -1941,17 +1941,14 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
   } else if (from.IsInteger32()) {
     info()->MarkAsDeferredCalling();
     if (to.IsTagged()) {
+      LOperand* value = UseRegister(val);
       if (!instr->CheckFlag(HValue::kCanOverflow)) {
-        LOperand* value = UseRegister(val);
         return DefineSameAsFirst(new(zone()) LSmiTag(value));
       } else if (val->CheckFlag(HInstruction::kUint32)) {
-        LOperand* value = UseRegister(val);
-        LOperand* temp1 = TempRegister();
-        LOperand* temp2 = FixedTemp(xmm1);
-        LNumberTagU* result = new(zone()) LNumberTagU(value, temp1, temp2);
+        LOperand* temp = TempRegister();
+        LNumberTagU* result = new(zone()) LNumberTagU(value, temp);
         return AssignPointerMap(DefineSameAsFirst(result));
       } else {
-        LOperand* value = UseRegister(val);
         LOperand* temp = TempRegister();
         LNumberTagI* result = new(zone()) LNumberTagI(value, temp);
         return AssignPointerMap(DefineSameAsFirst(result));
@@ -1966,9 +1963,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
     } else {
       ASSERT(to.IsDouble());
       if (val->CheckFlag(HInstruction::kUint32)) {
-        LOperand* temp = FixedTemp(xmm1);
-        return DefineAsRegister(
-            new(zone()) LUint32ToDouble(UseRegister(val), temp));
+        return DefineAsRegister(new(zone()) LUint32ToDouble(UseRegister(val)));
       } else {
         return DefineAsRegister(new(zone()) LInteger32ToDouble(Use(val)));
       }