glibc/sysdeps/alpha/atomicity.h
1999-06-21 13:00:14 +00:00

103 lines
2.3 KiB
C

/* Low-level functions for atomic operations. Alpha version.
Copyright (C) 1999 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, tmp;
__asm__ __volatile__ (
"/* Inline exchange & add */\n"
"1:\t"
"ldl_l %0,%3\n\t"
"addl %0,%4,%1\n\t"
"stl_c %1,%2\n\t"
"beq %1,2f\n"
".subsection 1\n"
"2:\t"
"br 1b\n"
".previous\n\t"
"mb\n\t"
"/* End exchange & add */"
: "=&r"(result), "=&r"(tmp), "=m"(*mem)
: "m" (*mem), "r"(val));
return result;
}
static inline void
__attribute__ ((unused))
atomic_add (volatile uint32_t *mem, int val)
{
register int result;
__asm__ __volatile__ (
"/* Inline exchange & add */\n"
"1:\t"
"ldl_l %0,%2\n\t"
"addl %0,%3,%0\n\t"
"stl_c %0,%1\n\t"
"beq %0,2f\n\t"
".subsection 1\n"
"2:\t"
"br 1b\n"
".previous\n\t"
"mb\n\t"
"/* End exchange & add */"
: "=&r"(result), "=m"(*mem)
: "m" (*mem), "r"(val));
}
static inline long
__attribute__ ((unused))
compare_and_swap (volatile long int *p, long int oldval, long int newval)
{
long int ret;
__asm__ __volatile__ (
"/* Inline compare & swap */\n"
"1:\t"
"ldq_l %0,%4\n\t"
"cmpeq %0,%2,%0\n\t"
"beq %0,3f\n\t"
"mov %3,%0\n\t"
"stq_c %0,%1\n\t"
"beq %0,2f\n\t"
".subsection 1\n"
"2:\t"
"br 1b\n"
".previous\n\t"
"3:\t"
"mb\n\t"
"/* End compare & swap */"
: "=&r"(ret), "=m"(*p)
: "r"(oldval), "r"(newval), "m"(*p));
return ret;
}
#endif /* atomicity.h */