| // Low-level functions for atomic operations: x86, x >= 4 version -*- C++ -*- |
| |
| // Copyright (C) 1999-2021 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/>. |
| |
| #include <ext/atomicity.h> |
| |
| namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| |
| _Atomic_word |
| __attribute__ ((__unused__)) |
| __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw () |
| { |
| register _Atomic_word __result; |
| __asm__ __volatile__ ("lock; xadd{l} {%0,%1|%1,%0}" |
| : "=r" (__result), "=m" (*__mem) |
| : "0" (__val), "m" (*__mem)); |
| return __result; |
| } |
| |
| void |
| __attribute__ ((__unused__)) |
| __atomic_add(volatile _Atomic_word* __mem, int __val) throw () |
| { |
| __asm__ __volatile__ ("lock; add{l} {%1,%0|%0,%1}" |
| : "=m" (*__mem) : "ir" (__val), "m" (*__mem)); |
| } |
| |
| _GLIBCXX_END_NAMESPACE_VERSION |
| } // namespace |
| |
