1*e4b17023SJohn Marino // Low-level type for atomic operations -*- C++ -*- 2*e4b17023SJohn Marino 3*e4b17023SJohn Marino // Copyright (C) 2004, 2009 Free Software Foundation, Inc. 4*e4b17023SJohn Marino // 5*e4b17023SJohn Marino // This file is part of the GNU ISO C++ Library. This library is free 6*e4b17023SJohn Marino // software; you can redistribute it and/or modify it under the 7*e4b17023SJohn Marino // terms of the GNU General Public License as published by the 8*e4b17023SJohn Marino // Free Software Foundation; either version 3, or (at your option) 9*e4b17023SJohn Marino // any later version. 10*e4b17023SJohn Marino 11*e4b17023SJohn Marino // This library is distributed in the hope that it will be useful, 12*e4b17023SJohn Marino // but WITHOUT ANY WARRANTY; without even the implied warranty of 13*e4b17023SJohn Marino // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14*e4b17023SJohn Marino // GNU General Public License for more details. 15*e4b17023SJohn Marino 16*e4b17023SJohn Marino // Under Section 7 of GPL version 3, you are granted additional 17*e4b17023SJohn Marino // permissions described in the GCC Runtime Library Exception, version 18*e4b17023SJohn Marino // 3.1, as published by the Free Software Foundation. 19*e4b17023SJohn Marino 20*e4b17023SJohn Marino // You should have received a copy of the GNU General Public License and 21*e4b17023SJohn Marino // a copy of the GCC Runtime Library Exception along with this program; 22*e4b17023SJohn Marino // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23*e4b17023SJohn Marino // <http://www.gnu.org/licenses/>. 24*e4b17023SJohn Marino 25*e4b17023SJohn Marino /** @file atomic_word.h 26*e4b17023SJohn Marino * This file is a GNU extension to the Standard C++ Library. 27*e4b17023SJohn Marino */ 28*e4b17023SJohn Marino 29*e4b17023SJohn Marino #ifndef _GLIBCXX_ATOMIC_WORD_H 30*e4b17023SJohn Marino #define _GLIBCXX_ATOMIC_WORD_H 1 31*e4b17023SJohn Marino 32*e4b17023SJohn Marino typedef int _Atomic_word; 33*e4b17023SJohn Marino 34*e4b17023SJohn Marino // Define these two macros using the appropriate memory barrier for the target. 35*e4b17023SJohn Marino // The commented out versions below are the defaults. 36*e4b17023SJohn Marino // See ia64/atomic_word.h for an alternative approach. 37*e4b17023SJohn Marino 38*e4b17023SJohn Marino // This one prevents loads from being hoisted across the barrier; 39*e4b17023SJohn Marino // in other words, this is a Load-Load acquire barrier. 40*e4b17023SJohn Marino // This is necessary iff TARGET_RELAXED_ORDERING is defined in tm.h. 41*e4b17023SJohn Marino // #define _GLIBCXX_READ_MEM_BARRIER __asm __volatile ("":::"memory") 42*e4b17023SJohn Marino 43*e4b17023SJohn Marino // This one prevents stores from being sunk across the barrier; in other 44*e4b17023SJohn Marino // words, a Store-Store release barrier. 45*e4b17023SJohn Marino // #define _GLIBCXX_WRITE_MEM_BARRIER __asm __volatile ("":::"memory") 46*e4b17023SJohn Marino 47*e4b17023SJohn Marino #endif 48