| // Low-level type for atomic operations -*- C++ -*- |
| |
| // Copyright (C) 2004, 2009 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 3, 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. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| /** @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 |
