| // Low-level functions for atomic operations: S/390 version -*- C++ -*- |
| |
| // Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 2, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING. If not, write to the Free |
| // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
| // USA. |
| |
| // As a special exception, you may use this file as part of a free software |
| // library without restriction. Specifically, if other files instantiate |
| // templates or use macros or inline functions from this file, or you compile |
| // this file and link it with other files to produce an executable, this |
| // file does not by itself cause the resulting executable to be covered by |
| // the GNU General Public License. This exception does not however |
| // invalidate any other reasons why the executable file might be covered by |
| // the GNU General Public License. |
| |
| #include <bits/atomicity.h> |
| |
| namespace __gnu_cxx |
| { |
| _Atomic_word |
| __attribute__ ((__unused__)) |
| __exchange_and_add(volatile _Atomic_word* __mem, int __val) |
| { |
| register _Atomic_word __old_val, __new_val; |
| |
| __asm__ __volatile__ (" l %0,0(%3)\n" |
| "0: lr %1,%0\n" |
| " ar %1,%4\n" |
| " cs %0,%1,0(%3)\n" |
| " jl 0b" |
| : "=&d" (__old_val), "=&d" (__new_val), "=m" (*__mem) |
| : "a" (__mem), "d" (__val), "m" (*__mem) |
| : "cc", "memory"); |
| return __old_val; |
| } |
| |
| void |
| __attribute__ ((__unused__)) |
| __atomic_add(volatile _Atomic_word* __mem, int __val) |
| { __exchange_and_add(__mem, __val); } |
| } // namespace __gnu_cxx |
