Revert "Don't need a temp register for StoreKeyed double"

src/x64/lithium-x64.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 2096 matching lines @@
   if (!instr->is_typed_elements()) {
     ASSERT(instr->elements()->representation().IsTagged());
     bool needs_write_barrier = instr->NeedsWriteBarrier();
     LOperand* object = NULL;
     LOperand* key = NULL;
     LOperand* val = NULL;
 
     Representation value_representation = instr->value()->representation();
     if (value_representation.IsDouble()) {
       object = UseRegisterAtStart(instr->elements());
-      val = UseRegisterAtStart(instr->value());
+      val = UseTempRegister(instr->value());
       key = UseRegisterOrConstantAtStart(instr->key());
     } else {
       ASSERT(value_representation.IsSmiOrTagged() ||
              value_representation.IsInteger32());
       if (needs_write_barrier) {
         object = UseTempRegister(instr->elements());
         val = UseTempRegister(instr->value());
         key = UseTempRegister(instr->key());
       } else {
         object = UseRegisterAtStart(instr->elements());
@@ skipping 403 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64