1 // Low-level functions for atomic operations: PA-RISC version -*- C++ -*- 2 3 // Copyright (C) 2002, 2004, 2005, 2009 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 3, 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 // 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. 19 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/>. 24 25 #include <bits/c++config.h> 26 #include <ext/atomicity.h> 27 28 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) 29 30 template<int _Inst> 31 struct _Atomicity_lock 32 { 33 static volatile int _S_atomicity_lock; 34 }; 35 36 template<int _Inst> 37 volatile int 38 _Atomicity_lock<_Inst>::_S_atomicity_lock __attribute__ ((aligned (16))) = 1; 39 40 // Because of the lack of weak support when using the hpux som 41 // linker, we explicitly instantiate the atomicity lock. 42 template volatile int _Atomicity_lock<0>::_S_atomicity_lock; 43 44 int 45 __attribute__ ((__unused__)) 46 __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw () 47 { 48 _Atomic_word result; 49 int tmp; 50 volatile int& lock = _Atomicity_lock<0>::_S_atomicity_lock; 51 52 __asm__ __volatile__ ("ldcw 0(%1),%0\n\t" 53 "cmpib,<>,n 0,%0,.+20\n\t" 54 "ldw 0(%1),%0\n\t" 55 "cmpib,= 0,%0,.-4\n\t" 56 "nop\n\t" 57 "b,n .-20" 58 : "=&r" (tmp) 59 : "r" (&lock) 60 : "memory"); 61 62 result = *__mem; 63 *__mem = result + __val; 64 __asm__ __volatile__ ("stw %1,0(%0)" 65 : : "r" (&lock), "r" (tmp) : "memory"); 66 return result; 67 } 68 69 void 70 __attribute__ ((__unused__)) 71 __atomic_add(volatile _Atomic_word* __mem, int __val) throw () 72 { 73 int tmp; 74 volatile int& lock = _Atomicity_lock<0>::_S_atomicity_lock; 75 76 __asm__ __volatile__ ("ldcw 0(%1),%0\n\t" 77 "cmpib,<>,n 0,%0,.+20\n\t" 78 "ldw 0(%1),%0\n\t" 79 "cmpib,= 0,%0,.-4\n\t" 80 "nop\n\t" 81 "b,n .-20" 82 : "=&r" (tmp) 83 : "r" (&lock) 84 : "memory"); 85 86 *__mem += __val; 87 __asm__ __volatile__ ("stw %1,0(%0)" 88 : : "r" (&lock), "r" (tmp) : "memory"); 89 } 90 91 _GLIBCXX_END_NAMESPACE 92