glibc/sysdeps/m68k/m68020/atomicity.h

65 lines
2.0 KiB
C

/* Low-level functions for atomic operations. m680x0 version, x >= 2.
Copyright (C) 1997 Free Software Foundation, Inc.
Contributed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>.
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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; 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 = *mem;
register int temp;
__asm__ __volatile__ ("1: move%.l %0,%1;"
" add%.l %2,%1;"
" cas%.l %0,%1,%3;"
" jbne 1b"
: "=d" (result), "=&d" (temp)
: "d" (val), "m" (*mem), "0" (result) : "memory");
return result;
}
static inline void
__attribute__ ((unused))
atomic_add (volatile uint32_t *mem, int val)
{
/* XXX Use cas here as well? */
__asm__ __volatile__ ("add%.l %0,%1"
: : "id" (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__ ("cas%.l %2,%3,%1; seq %0"
: "=dm" (ret), "=m" (*p), "=d" (readval)
: "d" (newval), "m" (*p), "2" (oldval));
return ret;
}
#endif /* atomicity.h */