atomicity.h revision 117397
1117397Skan// Low-level functions for atomic operations: x86, x >= 4 version -*- C++ -*- 2117397Skan 3117397Skan// Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. 4117397Skan// 5117397Skan// This file is part of the GNU ISO C++ Library. This library is free 6117397Skan// software; you can redistribute it and/or modify it under the 7117397Skan// terms of the GNU General Public License as published by the 8117397Skan// Free Software Foundation; either version 2, or (at your option) 9117397Skan// any later version. 10117397Skan 11117397Skan// This library is distributed in the hope that it will be useful, 12117397Skan// but WITHOUT ANY WARRANTY; without even the implied warranty of 13117397Skan// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14117397Skan// GNU General Public License for more details. 15117397Skan 16117397Skan// You should have received a copy of the GNU General Public License along 17117397Skan// with this library; see the file COPYING. If not, write to the Free 18117397Skan// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, 19117397Skan// USA. 20117397Skan 21117397Skan// As a special exception, you may use this file as part of a free software 22117397Skan// library without restriction. Specifically, if other files instantiate 23117397Skan// templates or use macros or inline functions from this file, or you compile 24117397Skan// this file and link it with other files to produce an executable, this 25117397Skan// file does not by itself cause the resulting executable to be covered by 26117397Skan// the GNU General Public License. This exception does not however 27117397Skan// invalidate any other reasons why the executable file might be covered by 28117397Skan// the GNU General Public License. 29117397Skan 30117397Skan#ifndef _BITS_ATOMICITY_H 31117397Skan#define _BITS_ATOMICITY_H 1 32117397Skan 33117397Skantypedef int _Atomic_word; 34117397Skan 35117397Skanstatic inline _Atomic_word 36117397Skan__attribute__ ((__unused__)) 37117397Skan__exchange_and_add (volatile _Atomic_word *__mem, int __val) 38117397Skan{ 39117397Skan register _Atomic_word __result; 40117397Skan __asm__ __volatile__ ("lock; xadd{l} {%0,%1|%1,%0}" 41117397Skan : "=r" (__result), "+m" (*__mem) 42117397Skan : "0" (__val) 43117397Skan : "memory"); 44117397Skan return __result; 45117397Skan} 46117397Skan 47117397Skanstatic inline void 48117397Skan__attribute__ ((__unused__)) 49117397Skan__atomic_add (volatile _Atomic_word* __mem, int __val) 50117397Skan{ 51117397Skan __asm__ __volatile__ ("lock; add{l} {%1,%0|%0,%1}" 52117397Skan : "+m" (*__mem) : "ir" (__val) : "memory"); 53117397Skan} 54117397Skan 55117397Skan#endif /* atomicity.h */ 56117397Skan 57117397Skan 58