Fix unary sub IC heap number code on x64: an untagged double was pushed on the stack and GCd.

src/ia32/code-stubs-ia32.cc

 // Copyright 2011 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 692 matching lines @@
 }
 
 
 void TypeRecordingUnaryOpStub::GenerateHeapNumberCodeSub(MacroAssembler* masm,
                                                          Label* slow) {
   __ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
   __ cmp(edx, masm->isolate()->factory()->heap_number_map());
   __ j(not_equal, slow);
 
   if (mode_ == UNARY_OVERWRITE) {
-    __ mov(edx, FieldOperand(eax, HeapNumber::kExponentOffset));
-    __ xor_(edx, HeapNumber::kSignMask);  // Flip sign.
-    __ mov(FieldOperand(eax, HeapNumber::kExponentOffset), edx);
+    __ xor_(FieldOperand(eax, HeapNumber::kExponentOffset),
+            Immediate(HeapNumber::kSignMask));  // Flip sign.
   } else {
     __ mov(edx, Operand(eax));
     // edx: operand
 
     Label slow_allocate_heapnumber, heapnumber_allocated;
     __ AllocateHeapNumber(eax, ebx, ecx, &slow_allocate_heapnumber);
     __ jmp(&heapnumber_allocated);
 
     __ bind(&slow_allocate_heapnumber);
     __ EnterInternalFrame();
@@ skipping 5132 matching lines @@
   // Do a tail call to the rewritten stub.
   __ jmp(Operand(edi));
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32