| // Low-level functions for atomic operations: Alpha version -*- C++ -*- |
| |
| // Copyright (C) 1999, 2000, 2001, 2003, 2004 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 2, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING. If not, write to the Free |
| // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
| // USA. |
| |
| // As a special exception, you may use this file as part of a free software |
| // library without restriction. Specifically, if other files instantiate |
| // templates or use macros or inline functions from this file, or you compile |
| // this file and link it with other files to produce an executable, this |
| // file does not by itself cause the resulting executable to be covered by |
| // the GNU General Public License. This exception does not however |
| // invalidate any other reasons why the executable file might be covered by |
| // the GNU General Public License. |
| |
| #include <bits/atomicity.h> |
| |
| /* @@@ With gas we can play nice .subsection games to get the |
| non-predicted branch pointing forward. But Digital assemblers |
| don't understand those directives. This isn't a terribly |
| important issue, so just ignore it. */ |
| |
| namespace __gnu_cxx |
| { |
| _Atomic_word |
| __attribute__ ((__unused__)) |
| __exchange_and_add(volatile _Atomic_word* __mem, int __val) |
| { |
| register int __result, __tmp; |
| |
| __asm__ __volatile__ ( |
| "\n$Lxadd_%=:\n\t" |
| "ldl_l %0,%3\n\t" |
| "addl %0,%4,%1\n\t" |
| "stl_c %1,%2\n\t" |
| "beq %1,$Lxadd_%=\n\t" |
| "mb" |
| : "=&r"(__result), "=&r"(__tmp), "=m"(*__mem) |
| : "m" (*__mem), "r"(__val)); |
| |
| return __result; |
| } |
| |
| void |
| __attribute__ ((__unused__)) |
| __atomic_add(volatile _Atomic_word* __mem, int __val) |
| { |
| register _Atomic_word __result; |
| |
| __asm__ __volatile__ ( |
| "\n$Ladd_%=:\n\t" |
| "ldl_l %0,%2\n\t" |
| "addl %0,%3,%0\n\t" |
| "stl_c %0,%1\n\t" |
| "beq %0,$Ladd_%=\n\t" |
| "mb" |
| : "=&r"(__result), "=m"(*__mem) |
| : "m" (*__mem), "r"(__val)); |
| } |
| } // namespace __gnu_cxx |
| |
