atomicity.h revision 256281
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 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__)) 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