1// Low-level functions for atomic operations: MIPS version  -*- C++ -*-
2
3// Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4//
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)
9// any later version.
10
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.
15
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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
19// USA.
20
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.
29
30#include <bits/atomicity.h>
31
32namespace __gnu_cxx
33{
34  _Atomic_word
35  __attribute__ ((__unused__))
36  __exchange_and_add(volatile _Atomic_word* __mem, int __val)
37  {
38    _Atomic_word __result, __tmp;
39
40    __asm__ __volatile__
41      ("/* Inline exchange & add */\n\t"
42       "1:\n\t"
43       ".set	push\n\t"
44#if _MIPS_SIM == _ABIO32
45       ".set	mips2\n\t"
46#endif
47       "ll	%0,0(%2)\n\t"
48       "addu	%1,%3,%0\n\t"
49       "sc	%1,0(%2)\n\t"
50       ".set	pop\n\t"
51       "beqz	%1,1b\n\t"
52       "/* End exchange & add */"
53       : "=&r"(__result), "=&r"(__tmp)
54       : "r"(__mem), "r"(__val)
55       :  "memory" );
56
57    return __result;
58  }
59
60  void
61  __attribute__ ((__unused__))
62  __atomic_add(volatile _Atomic_word* __mem, int __val)
63  {
64    _Atomic_word __result;
65
66    __asm__ __volatile__
67      ("/* Inline atomic add */\n\t"
68       "1:\n\t"
69       ".set	push\n\t"
70#if _MIPS_SIM == _ABIO32
71       ".set	mips2\n\t"
72#endif
73       "ll	%0,0(%1)\n\t"
74       "addu	%0,%2,%0\n\t"
75       "sc	%0,0(%1)\n\t"
76       ".set	pop\n\t"
77       "beqz	%0,1b\n\t"
78       "/* End atomic add */"
79       : "=&r"(__result)
80       : "r"(__mem), "r"(__val)
81       : "memory" );
82  }
83} // namespace __gnu_cxx
84