1 // Low-level functions for atomic operations: MIPS version -*- C++ -*-
2
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
4 // Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 2, or (at your option)
10 // any later version.
11
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16
17 // You should have received a copy of the GNU General Public License along
18 // with this library; see the file COPYING. If not, write to the Free
19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
20 // USA.
21
22 // As a special exception, you may use this file as part of a free software
23 // library without restriction. Specifically, if other files instantiate
24 // templates or use macros or inline functions from this file, or you compile
25 // this file and link it with other files to produce an executable, this
26 // file does not by itself cause the resulting executable to be covered by
27 // the GNU General Public License. This exception does not however
28 // invalidate any other reasons why the executable file might be covered by
29 // the GNU General Public License.
30
31 #include <ext/atomicity.h>
32
_GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)33 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
34
35 // NB: MIPS II or above required.
36 _Atomic_word
37 __attribute__ ((__unused__))
38 __exchange_and_add(volatile _Atomic_word* __mem, int __val)
39 {
40 _Atomic_word __result, __tmp;
41
42 __asm__ __volatile__
43 ("/* Inline exchange & add */\n\t"
44 "1:\n\t"
45 ".set push\n\t"
46 #if _MIPS_SIM == _ABIO32
47 ".set mips2\n\t"
48 #endif
49 "ll %0,0(%2)\n\t"
50 "addu %1,%3,%0\n\t"
51 "sc %1,0(%2)\n\t"
52 ".set pop\n\t"
53 "beqz %1,1b\n\t"
54 "/* End exchange & add */"
55 : "=&r"(__result), "=&r"(__tmp)
56 : "r"(__mem), "r"(__val)
57 : "memory" );
58
59 return __result;
60 }
61
62 void
63 __attribute__ ((__unused__))
__atomic_add(volatile _Atomic_word * __mem,int __val)64 __atomic_add(volatile _Atomic_word* __mem, int __val)
65 {
66 _Atomic_word __result;
67
68 __asm__ __volatile__
69 ("/* Inline atomic add */\n\t"
70 "1:\n\t"
71 ".set push\n\t"
72 #if _MIPS_SIM == _ABIO32
73 ".set mips2\n\t"
74 #endif
75 "ll %0,0(%1)\n\t"
76 "addu %0,%2,%0\n\t"
77 "sc %0,0(%1)\n\t"
78 ".set pop\n\t"
79 "beqz %0,1b\n\t"
80 "/* End atomic add */"
81 : "=&r"(__result)
82 : "r"(__mem), "r"(__val)
83 : "memory" );
84 }
85
86 _GLIBCXX_END_NAMESPACE
87