freebsd-dev/contrib/libstdc++/config/cpu/s390/atomicity.h
2003-07-11 03:42:04 +00:00

61 lines
2.2 KiB
C++

// Low-level functions for atomic operations: S/390 version -*- C++ -*-
// Copyright (C) 2001 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.
#ifndef _BITS_ATOMICITY_H
#define _BITS_ATOMICITY_H 1
typedef int _Atomic_word;
static inline _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(%2)\n"
"0: lr %1,%0\n"
" ar %1,%3\n"
" cs %0,%1,0(%2)\n"
" jl 0b"
: "=&d" (__old_val), "=&d" (__new_val)
: "a" (__mem), "d" (__val) : "cc", "memory" );
return __old_val;
}
static inline void
__attribute__ ((__unused__))
__atomic_add (volatile _Atomic_word *__mem, int __val)
{
__exchange_and_add (__mem, __val);
}
#endif /* atomicity.h */