s390: implement atomic exchange on TF

src/s390/assembler-s390.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 1045 matching lines @@
 
   // Compare Instructions
   void chi(Register r, const Operand& opnd);
   void cghi(Register r, const Operand& opnd);
 
   // Compare Logical Instructions
   void cli(const MemOperand& mem, const Operand& imm);
   void cliy(const MemOperand& mem, const Operand& imm);
   void clc(const MemOperand& opnd1, const MemOperand& opnd2, Length length);
 
+  // Compare and Swap Instructions
+  void cs(Register r1, Register r2, const MemOperand& src);
+  void csy(Register r1, Register r2, const MemOperand& src);
+  void csg(Register r1, Register r2, const MemOperand& src);
+
   // Test Under Mask Instructions
   void tm(const MemOperand& mem, const Operand& imm);
   void tmy(const MemOperand& mem, const Operand& imm);
 
   // Rotate Instructions
   void rll(Register r1, Register r3, Register opnd);
   void rll(Register r1, Register r3, const Operand& opnd);
   void rll(Register r1, Register r3, Register r2, const Operand& opnd);
   void rllg(Register r1, Register r3, const Operand& opnd);
   void rllg(Register r1, Register r3, const Register opnd);
@@ skipping 391 matching lines @@
 
 class EnsureSpace BASE_EMBEDDED {
  public:
   explicit EnsureSpace(Assembler* assembler) { assembler->CheckBuffer(); }
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_S390_ASSEMBLER_S390_H_