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-rw-r--r--gcc-4.4.3/libgomp/config/linux/futex.h80
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diff --git a/gcc-4.4.3/libgomp/config/linux/futex.h b/gcc-4.4.3/libgomp/config/linux/futex.h
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index 000000000..3c8345086
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+++ b/gcc-4.4.3/libgomp/config/linux/futex.h
@@ -0,0 +1,80 @@
+/* Copyright (C) 2010, 2011 Free Software Foundation, Inc.
+ Contributed by ARM Ltd.
+
+ 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/>. */
+
+/* Provide target-specific access to the futex system call. */
+
+/* The include file hierachy above us (wait.h) has pushed visibility
+ hidden, this will be applied to prototypes with headers we include
+ with the effect that we cannot link against an external function
+ (syscall). The solution here is to push default visibility, include
+ our required headers then reinstante the original visibility. */
+
+#pragma GCC visibility push(default)
+
+#undef _GNU_SOURCE /* could be previously defined to 1 instead */
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <sys/syscall.h>
+
+#pragma GCC visibility pop
+
+#if !defined(SYS_futex)
+#define SYS_futex __NR_futex
+#endif
+
+static inline void
+futex_wait (int *addr, int val)
+{
+ long err = syscall (SYS_futex, addr, gomp_futex_wait, val, NULL);
+ if (__builtin_expect (err == -ENOSYS, 0))
+ {
+ gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
+ gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
+ syscall (SYS_futex, addr, gomp_futex_wait, val, NULL);
+ }
+}
+
+static inline void
+futex_wake (int *addr, int count)
+{
+ long err = syscall (SYS_futex, addr, gomp_futex_wake, count);
+ if (__builtin_expect (err == -ENOSYS, 0))
+ {
+ gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
+ gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
+ syscall (SYS_futex, addr, gomp_futex_wake, count);
+ }
+}
+
+static inline void
+cpu_relax (void)
+{
+ __asm volatile ("" : : : "memory");
+}
+
+static inline void
+atomic_write_barrier (void)
+{
+ __sync_synchronize ();
+}