s390: exploit high-word facility for Smi Ops

src/s390/macro-assembler-s390.h

 // Copyright 2014 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_S390_MACRO_ASSEMBLER_S390_H_
 #define V8_S390_MACRO_ASSEMBLER_S390_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 810 matching lines @@
 
   void StoreHalfWord(Register src, const MemOperand& mem,
                      Register scratch = r0);
   void StoreByte(Register src, const MemOperand& mem, Register scratch = r0);
 
   void LoadRepresentation(Register dst, const MemOperand& mem, Representation r,
                           Register scratch = no_reg);
   void StoreRepresentation(Register src, const MemOperand& mem,
                            Representation r, Register scratch = no_reg);
 
-  void AddSmiLiteral(Register dst, Register src, Smi* smi, Register scratch);
-  void SubSmiLiteral(Register dst, Register src, Smi* smi, Register scratch);
+  void AddSmiLiteral(Register dst, Register src, Smi* smi,
+                     Register scratch = r0);
+  void SubSmiLiteral(Register dst, Register src, Smi* smi,
+                     Register scratch = r0);
   void CmpSmiLiteral(Register src1, Smi* smi, Register scratch);
   void CmpLogicalSmiLiteral(Register src1, Smi* smi, Register scratch);
   void AndSmiLiteral(Register dst, Register src, Smi* smi);
 
   // Set new rounding mode RN to FPSCR
   void SetRoundingMode(FPRoundingMode RN);
 
   // reset rounding mode to default (kRoundToNearest)
   void ResetRoundingMode();
 
@@ skipping 967 matching lines @@
 inline MemOperand NativeContextMemOperand() {
   return ContextMemOperand(cp, Context::NATIVE_CONTEXT_INDEX);
 }
 
 #define ACCESS_MASM(masm) masm->
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_S390_MACRO_ASSEMBLER_S390_H_