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Diffstat (limited to 'sysdeps/i386/i486/atomicity.h')
-rw-r--r--sysdeps/i386/i486/atomicity.h57
1 files changed, 57 insertions, 0 deletions
diff --git a/sysdeps/i386/i486/atomicity.h b/sysdeps/i386/i486/atomicity.h
new file mode 100644
index 0000000000..98a2531365
--- /dev/null
+++ b/sysdeps/i386/i486/atomicity.h
@@ -0,0 +1,57 @@
+/* Low-level functions for atomitc operations. ix86 version, x >= 4.
+ Copyright (C) 1997 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;
+ __asm__ __volatile__ ("lock; xaddl %0,%1"
+ : "=r" (result) : "0" (val), "m" (*mem) : "memory");
+ return result;
+}
+
+static inline void
+__attribute__ ((unused))
+atomic_add (volatile uint32_t *mem, int val)
+{
+ __asm__ __volatile__ ("lock; addl %0,%1"
+ : : "ir" (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__ ("lock; cmpxchgl %3, %1; sete %0"
+ : "=q" (ret), "=m" (*p), "=a" (readval)
+ : "r" (newval), "m" (*p), "a" (oldval));
+ return ret;
+}
+
+#endif /* atomicity.h */