glibc/sysdeps/powerpc/atomicity.h

105 lines
2.6 KiB
C

/* Low-level functions for atomic operations. PowerPC version.
Copyright (C) 1997, 1998, 1999, 2000 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 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>
#if BROKEN_PPC_ASM_CR0
# define __ATOMICITY_INLINE /* nothing */
#else
# define __ATOMICITY_INLINE inline
#endif
static __ATOMICITY_INLINE int
__attribute__ ((unused))
exchange_and_add (volatile uint32_t *mem, int val)
{
int tmp, result;
__asm__ ("\n\
0: lwarx %0,0,%2 \n\
add%I3 %1,%0,%3 \n\
stwcx. %1,0,%2 \n\
bne- 0b \n\
" : "=&b"(result), "=&r"(tmp) : "r" (mem), "Ir"(val) : "cr0", "memory");
return result;
}
static __ATOMICITY_INLINE void
__attribute__ ((unused))
atomic_add (volatile uint32_t *mem, int val)
{
int tmp;
__asm__ ("\n\
0: lwarx %0,0,%1 \n\
add%I2 %0,%0,%2 \n\
stwcx. %0,0,%1 \n\
bne- 0b \n\
" : "=&b"(tmp) : "r" (mem), "Ir"(val) : "cr0", "memory");
}
static __ATOMICITY_INLINE int
__attribute__ ((unused))
compare_and_swap (volatile long int *p, long int oldval, long int newval)
{
int result;
__asm__ ("\n\
0: lwarx %0,0,%1 \n\
sub%I2c. %0,%0,%2 \n\
cntlzw %0,%0 \n\
bne- 1f \n\
stwcx. %3,0,%1 \n\
bne- 0b \n\
1: \n\
" : "=&b"(result) : "r"(p), "Ir"(oldval), "r"(newval) : "cr0", "memory");
return result >> 5;
}
static __ATOMICITY_INLINE long int
__attribute__ ((unused))
always_swap (volatile long int *p, long int newval)
{
long int result;
__asm__ ("\n\
0: lwarx %0,0,%1 \n\
stwcx. %2,0,%1 \n\
bne- 0b \n\
" : "=&r"(result) : "r"(p), "r"(newval) : "cr0", "memory");
return result;
}
static __ATOMICITY_INLINE int
__attribute__ ((unused))
test_and_set (volatile long int *p, long int newval)
{
int result;
__asm__ ("\n\
0: lwarx %0,0,%1 \n\
cmpwi %0,0 \n\
bne- 1f \n\
stwcx. %2,0,%1 \n\
bne- 0b \n\
1: \n\
" : "=&r"(result) : "r"(p), "r"(newval) : "cr0", "memory");
return result;
}
#endif /* atomicity.h */