gcc/libstdc++-v3/config/cpu/i386/bits/atomicity.h
Nathan Myers f17d6c73de cpu: Atomicity cleanups.
2000-04-24  Nathan Myers  <ncm@cantrip.org>

	* config/cpu: Atomicity cleanups.
	* config/cpu/alpha/bits: New directory.
	* config/cpu/arm/bits: New directory.
	* config/cpu/generic/bits: New directory.
	* config/cpu/i386/bits: New directory.
	* config/cpu/powerpc/bits: New directory.
	* config/cpu/sparc/sparc32/bits: New directory.
	* config/cpu/sparc/sparc32/bits: New directory.
	* config/cpu/*/bits: Move atomicity.h files to here.

From-SVN: r33438
2000-04-26 02:51:12 +00:00

59 lines
1.9 KiB
C

/* Low-level functions for atomic 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 _BITS_ATOMICITY_H
#define _BITS_ATOMICITY_H 1
typedef int _Atomic_word;
static inline _Atomic_word
__attribute__ ((unused))
__exchange_and_add (volatile _Atomic_word *__mem, int __val)
{
register _Atomic_word __result;
__asm__ __volatile__ ("lock; xaddl %0,%2"
: "=r" (__result)
: "0" (__val), "m" (*__mem)
: "memory");
return __result;
}
static inline void
__attribute__ ((unused))
__atomic_add (volatile _Atomic_word* __mem, int __val)
{
__asm__ __volatile__ ("lock; addl %0,%1"
: : "ir" (__val), "m" (*__mem) : "memory");
}
static inline char
__attribute__ ((unused))
__compare_and_swap (volatile long* __p, long __oldval, long __newval)
{
char __ret;
long __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 */