1 // Low-level functions for atomic operations: Alpha version -*- C++ -*-
3 // Copyright (C) 1999, 2000, 2001, 2003, 2004 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 2, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License along
17 // with this library; see the file COPYING. If not, write to the Free
18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
21 // As a special exception, you may use this file as part of a free software
22 // library without restriction. Specifically, if other files instantiate
23 // templates or use macros or inline functions from this file, or you compile
24 // this file and link it with other files to produce an executable, this
25 // file does not by itself cause the resulting executable to be covered by
26 // the GNU General Public License. This exception does not however
27 // invalidate any other reasons why the executable file might be covered by
28 // the GNU General Public License.
30 #include <bits/atomicity.h>
32 /* @@@ With gas we can play nice .subsection games to get the
33 non-predicted branch pointing forward. But Digital assemblers
34 don't understand those directives. This isn't a terribly
35 important issue, so just ignore it. */
40 __attribute__ ((__unused__))
41 __exchange_and_add(volatile _Atomic_word* __mem, int __val)
43 register int __result, __tmp;
45 __asm__ __volatile__ (
50 "beq %1,$Lxadd_%=\n\t"
52 : "=&r"(__result), "=&r"(__tmp), "=m"(*__mem)
53 : "m" (*__mem), "r"(__val));
59 __attribute__ ((__unused__))
60 __atomic_add(volatile _Atomic_word* __mem, int __val)
62 register _Atomic_word __result;
64 __asm__ __volatile__ (
71 : "=&r"(__result), "=m"(*__mem)
72 : "m" (*__mem), "r"(__val));
74 } // namespace __gnu_cxx