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Diffstat (limited to 'sysdeps/i386/i486/atomicity.h')
-rw-r--r-- | sysdeps/i386/i486/atomicity.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/sysdeps/i386/i486/atomicity.h b/sysdeps/i386/i486/atomicity.h new file mode 100644 index 0000000000..98a2531365 --- /dev/null +++ b/sysdeps/i386/i486/atomicity.h @@ -0,0 +1,57 @@ +/* Low-level functions for atomitc operations. ix86 version, x >= 4. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#ifndef _ATOMICITY_H +#define _ATOMICITY_H 1 + +#include <inttypes.h> + + +static inline int +__attribute__ ((unused)) +exchange_and_add (volatile uint32_t *mem, int val) +{ + register int result; + __asm__ __volatile__ ("lock; xaddl %0,%1" + : "=r" (result) : "0" (val), "m" (*mem) : "memory"); + return result; +} + +static inline void +__attribute__ ((unused)) +atomic_add (volatile uint32_t *mem, int val) +{ + __asm__ __volatile__ ("lock; addl %0,%1" + : : "ir" (val), "m" (*mem) : "memory"); +} + +static inline int +__attribute__ ((unused)) +compare_and_swap (volatile long int *p, long int oldval, long int newval) +{ + char ret; + long int readval; + + __asm__ __volatile__ ("lock; cmpxchgl %3, %1; sete %0" + : "=q" (ret), "=m" (*p), "=a" (readval) + : "r" (newval), "m" (*p), "a" (oldval)); + return ret; +} + +#endif /* atomicity.h */ |