| // Low-level type for atomic operations -*- C++ -*- |
| |
| // Copyright (C) 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
| // 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. |
| |
| /** @file atomic_word.h |
| * This file is a GNU extension to the Standard C++ Library. |
| */ |
| |
| #ifndef _GLIBCXX_ATOMIC_WORD_H |
| #define _GLIBCXX_ATOMIC_WORD_H 1 |
| |
| typedef int _Atomic_word; |
| |
| // Define these two macros using the appropriate memory barrier for the target. |
| // The commented out versions below are the defaults. |
| // See ia64/atomic_word.h for an alternative approach. |
| |
| // This one prevents loads from being hoisted across the barrier; |
| // in other words, this is a Load-Load acquire barrier. |
| // This is necessary iff TARGET_RELAXED_ORDERING is defined in tm.h. |
| // #define _GLIBCXX_READ_MEM_BARRIER __asm __volatile ("":::"memory") |
| |
| // This one prevents stores from being sunk across the barrier; in other |
| // words, a Store-Store release barrier. |
| // #define _GLIBCXX_WRITE_MEM_BARRIER __asm __volatile ("":::"memory") |
| |
| #endif |