1 // Low-level functions for atomic operations: PA-RISC version -*- C++ -*-
3 // Copyright (C) 2002-2016 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
25 #include <bits/c++config.h>
26 #include <ext/atomicity.h>
28 namespace __gnu_cxx
_GLIBCXX_VISIBILITY(default)
30 _GLIBCXX_BEGIN_NAMESPACE_VERSION
33 struct _Atomicity_lock
35 static volatile int _S_atomicity_lock
;
40 _Atomicity_lock
<_Inst
>::_S_atomicity_lock
__attribute__ ((aligned (16))) = 1;
42 // Because of the lack of weak support when using the hpux som
43 // linker, we explicitly instantiate the atomicity lock.
44 template volatile int _Atomicity_lock
<0>::_S_atomicity_lock
;
47 __attribute__ ((__unused__
))
48 __exchange_and_add(volatile _Atomic_word
* __mem
, int __val
) throw ()
52 volatile int& lock
= _Atomicity_lock
<0>::_S_atomicity_lock
;
54 __asm__
__volatile__ ("ldcw 0(%1),%0\n\t"
55 "cmpib,<>,n 0,%0,.+20\n\t"
57 "cmpib,= 0,%0,.-4\n\t"
65 *__mem
= result
+ __val
;
66 __asm__
__volatile__ ("stw %1,0(%0)"
67 : : "r" (&lock
), "r" (tmp
) : "memory");
72 __attribute__ ((__unused__
))
73 __atomic_add(volatile _Atomic_word
* __mem
, int __val
) throw ()
76 volatile int& lock
= _Atomicity_lock
<0>::_S_atomicity_lock
;
78 __asm__
__volatile__ ("ldcw 0(%1),%0\n\t"
79 "cmpib,<>,n 0,%0,.+20\n\t"
81 "cmpib,= 0,%0,.-4\n\t"
89 __asm__
__volatile__ ("stw %1,0(%0)"
90 : : "r" (&lock
), "r" (tmp
) : "memory");
93 _GLIBCXX_END_NAMESPACE_VERSION