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+/* Memory barrier operations. i386 version.
+ Copyright (C) 2002, 2008 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_MEMORY_H
+#define _BITS_MEMORY_H 1
+
+/* Prevent read and write reordering across this function. */
+static inline void
+__memory_barrier (void)
+{
+ int i;
+
+ /* Any lock'ed instruction will do. We just do a simple
+ increment. */
+ __asm__ __volatile ("lock; incl %0" : "=m" (i) : "m" (i) : "memory");
+}
+
+/* Prevent read reordering across this function. */
+#define __memory_read_barrier __memory_barrier
+
+/* Prevent write reordering across this function. */
+#define __memory_write_barrier __memory_barrier
+
+#endif