--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libgomp/config/linux/mutex.h	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,60 @@
+/* Copyright (C) 2005, 2009 Free Software Foundation, Inc.
+   Contributed by Richard Henderson <rth@redhat.com>.
+
+   This file is part of the GNU OpenMP Library (libgomp).
+
+   Libgomp is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   Libgomp 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 General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This is a Linux specific implementation of a mutex synchronization
+   mechanism for libgomp.  This type is private to the library.  This
+   implementation uses atomic instructions and the futex syscall.  */
+
+#ifndef GOMP_MUTEX_H
+#define GOMP_MUTEX_H 1
+
+typedef int gomp_mutex_t;
+
+#define GOMP_MUTEX_INIT_0 1
+
+static inline void gomp_mutex_init (gomp_mutex_t *mutex)
+{
+  *mutex = 0;
+}
+
+extern void gomp_mutex_lock_slow (gomp_mutex_t *mutex);
+static inline void gomp_mutex_lock (gomp_mutex_t *mutex)
+{
+  if (!__sync_bool_compare_and_swap (mutex, 0, 1))
+    gomp_mutex_lock_slow (mutex);
+}
+
+extern void gomp_mutex_unlock_slow (gomp_mutex_t *mutex);
+static inline void gomp_mutex_unlock (gomp_mutex_t *mutex)
+{
+  int val = __sync_lock_test_and_set (mutex, 0);
+  if (__builtin_expect (val > 1, 0))
+    gomp_mutex_unlock_slow (mutex);
+}
+
+static inline void gomp_mutex_destroy (gomp_mutex_t *mutex)
+{
+}
+
+#endif /* GOMP_MUTEX_H */