Introduce StackOperandForReturnAddress operand for X64 to access return address in the stack

R=danno@chromium.org

Review URL: https://codereview.chromium.org/20628003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15967 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/macro-assembler-x64.h

@@ -1518,6 +1518,10 @@ inline Operand StackSpaceOperand(int index) {
 }
 
 
+inline Operand StackOperandForReturnAddress(int32_t disp) {
+  return Operand(rsp, disp);
+}
+
 
 #ifdef GENERATED_CODE_COVERAGE
 extern void LogGeneratedCodeCoverage(const char* file_line);

src/x64/stub-cache-x64.cc

@@ -410,9 +410,9 @@ static void ReserveSpaceForFastApiCall(MacroAssembler* masm, Register scratch) {
   //  -- rsp[0] : return address
   //  -- rsp[8] : last argument in the internal frame of the caller
   // -----------------------------------
-  __ movq(scratch, Operand(rsp, 0));
+  __ movq(scratch, StackOperandForReturnAddress(0));
   __ subq(rsp, Immediate(kFastApiCallArguments * kPointerSize));
-  __ movq(Operand(rsp, 0), scratch);
+  __ movq(StackOperandForReturnAddress(0), scratch);
   __ Move(scratch, Smi::FromInt(0));
   for (int i = 1; i <= kFastApiCallArguments; i++) {
      __ movq(Operand(rsp, i * kPointerSize), scratch);
@@ -431,8 +431,9 @@ static void FreeSpaceForFastApiCall(MacroAssembler* masm, Register scratch) {
   //  -- rsp[kFastApiCallArguments * 8 + 8] : last argument in the internal
   //                                          frame.
   // -----------------------------------
-  __ movq(scratch, Operand(rsp, 0));
-  __ movq(Operand(rsp, kFastApiCallArguments * kPointerSize), scratch);
+  __ movq(scratch, StackOperandForReturnAddress(0));
+  __ movq(StackOperandForReturnAddress(kFastApiCallArguments * kPointerSize),
+          scratch);
   __ addq(rsp, Immediate(kPointerSize * kFastApiCallArguments));
 }
 
@@ -2350,8 +2351,9 @@ Handle<Code> CallStubCompiler::CompileFastApiCall(
                   name, depth, &miss);
 
   // Move the return address on top of the stack.
-  __ movq(rax, Operand(rsp, kFastApiCallArguments * kPointerSize));
-  __ movq(Operand(rsp, 0 * kPointerSize), rax);
+  __ movq(rax,
+          StackOperandForReturnAddress(kFastApiCallArguments * kPointerSize));
+  __ movq(StackOperandForReturnAddress(0), rax);
 
   GenerateFastApiCall(masm(), optimization, argc);