Subversion Repositories scarts

/* Low-level functions for atomic operations.  ix86 version, x >= 4.

   Copyright (C) 1997, 2000, 2001 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

static inline uint32_t

__attribute__ ((unused))

exchange_and_add (volatile uint32_t *mem, uint32_t val)

{

  register uint32_t result;

  __asm__ __volatile__ ("lock; xaddl %0,%1"

                        : "=r" (result), "=m" (*mem) : "m" (val), "1" (*mem));

  return result;

}

static inline void

__attribute__ ((unused))

atomic_add (volatile uint32_t *mem, int val)

{

  __asm__ __volatile__ ("lock; addl %1,%0"

                        : "=m" (*mem) : "ir" (val), "m" (*mem));

}

static inline char

__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), "1" (*p), "a" (oldval));

  return ret;

}

#endif /* atomicity.h */