1/* Copyright (C) 2005 Free Software Foundation, Inc.
2   Contributed by Richard Henderson <rth@redhat.com>.
3
4   This file is part of the GNU OpenMP Library (libgomp).
5
6   Libgomp is free software; you can redistribute it and/or modify it
7   under the terms of the GNU Lesser General Public License as published by
8   the Free Software Foundation; either version 2.1 of the License, or
9   (at your option) any later version.
10
11   Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
12   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13   FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
14   more details.
15
16   You should have received a copy of the GNU Lesser General Public License
17   along with libgomp; see the file COPYING.LIB.  If not, write to the
18   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
19   MA 02110-1301, USA.  */
20
21/* As a special exception, if you link this library with other files, some
22   of which are compiled with GCC, to produce an executable, this library
23   does not by itself cause the resulting executable to be covered by the
24   GNU General Public License.  This exception does not however invalidate
25   any other reasons why the executable file might be covered by the GNU
26   General Public License.  */
27
28/* Provide target-specific access to the futex system call.  */
29
30#include <sys/syscall.h>
31#define FUTEX_WAIT	0
32#define FUTEX_WAKE	1
33
34static inline void
35sys_futex0 (int *addr, int op, int val)
36{
37  register long int r0  __asm__ ("r0");
38  register long int r3  __asm__ ("r3");
39  register long int r4  __asm__ ("r4");
40  register long int r5  __asm__ ("r5");
41  register long int r6  __asm__ ("r6");
42
43  r0 = SYS_futex;
44  r3 = (long) addr;
45  r4 = op;
46  r5 = val;
47  r6 = 0;
48
49  /* ??? The powerpc64 sysdep.h file clobbers ctr; the powerpc32 sysdep.h
50     doesn't.  It doesn't much matter for us.  In the interest of unity,
51     go ahead and clobber it always.  */
52
53  __asm volatile ("sc"
54		  : "=r"(r0), "=r"(r3), "=r"(r4), "=r"(r5), "=r"(r6)
55		  : "r"(r0), "r"(r3), "r"(r4), "r"(r5), "r"(r6)
56		  : "r7", "r8", "r9", "r10", "r11", "r12",
57		    "cr0", "ctr", "memory");
58}
59
60static inline void
61futex_wait (int *addr, int val)
62{
63  sys_futex0 (addr, FUTEX_WAIT, val);
64}
65
66static inline void
67futex_wake (int *addr, int count)
68{
69  sys_futex0 (addr, FUTEX_WAKE, count);
70}
71