1169695Skan/* Copyright (C) 2005 Free Software Foundation, Inc.
2169695Skan   Contributed by Richard Henderson <rth@redhat.com>.
3169695Skan
4169695Skan   This file is part of the GNU OpenMP Library (libgomp).
5169695Skan
6169695Skan   Libgomp is free software; you can redistribute it and/or modify it
7169695Skan   under the terms of the GNU Lesser General Public License as published by
8169695Skan   the Free Software Foundation; either version 2.1 of the License, or
9169695Skan   (at your option) any later version.
10169695Skan
11169695Skan   Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
12169695Skan   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13169695Skan   FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
14169695Skan   more details.
15169695Skan
16169695Skan   You should have received a copy of the GNU Lesser General Public License
17169695Skan   along with libgomp; see the file COPYING.LIB.  If not, write to the
18169695Skan   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
19169695Skan   MA 02110-1301, USA.  */
20169695Skan
21169695Skan/* As a special exception, if you link this library with other files, some
22169695Skan   of which are compiled with GCC, to produce an executable, this library
23169695Skan   does not by itself cause the resulting executable to be covered by the
24169695Skan   GNU General Public License.  This exception does not however invalidate
25169695Skan   any other reasons why the executable file might be covered by the GNU
26169695Skan   General Public License.  */
27169695Skan
28169695Skan/* Provide target-specific access to the futex system call.  */
29169695Skan
30169695Skan#define FUTEX_WAIT	0
31169695Skan#define FUTEX_WAKE	1
32169695Skan
33169695Skan#ifdef __LP64__
34169695Skan# ifndef SYS_futex
35169695Skan#  define SYS_futex	202
36169695Skan# endif
37169695Skan
38169695Skanstatic inline void
39169695Skanfutex_wait (int *addr, int val)
40169695Skan{
41169695Skan  register long r10 __asm__("%r10") = 0;
42169695Skan  long res;
43169695Skan
44169695Skan  __asm volatile ("syscall"
45169695Skan		  : "=a" (res)
46169695Skan		  : "0"(SYS_futex), "D" (addr), "S"(FUTEX_WAIT),
47169695Skan		    "d"(val), "r"(r10)
48169695Skan		  : "r11", "rcx", "memory");
49169695Skan}
50169695Skan
51169695Skanstatic inline void
52169695Skanfutex_wake (int *addr, int count)
53169695Skan{
54169695Skan  long res;
55169695Skan
56169695Skan  __asm volatile ("syscall"
57169695Skan		  : "=a" (res)
58169695Skan		  : "0"(SYS_futex), "D" (addr), "S"(FUTEX_WAKE), "d"(count)
59169695Skan		  : "r11", "rcx", "memory");
60169695Skan}
61169695Skan#else
62169695Skan# ifndef SYS_futex
63169695Skan#  define SYS_futex	240
64169695Skan# endif
65169695Skan
66169695Skan# ifdef __PIC__
67169695Skan
68169695Skanstatic inline void
69169695Skansys_futex0 (int *addr, int op, int val)
70169695Skan{
71169695Skan  long res;
72169695Skan
73169695Skan  __asm volatile ("xchgl\t%%ebx, %2\n\t"
74169695Skan		  "int\t$0x80\n\t"
75169695Skan		  "xchgl\t%%ebx, %2"
76169695Skan		  : "=a" (res)
77169695Skan		  : "0"(SYS_futex), "r" (addr), "c"(op),
78169695Skan		    "d"(val), "S"(0)
79169695Skan		  : "memory");
80169695Skan}
81169695Skan
82169695Skan# else
83169695Skan
84169695Skanstatic inline void
85169695Skansys_futex0 (int *addr, int op, int val)
86169695Skan{
87169695Skan  long res;
88169695Skan
89169695Skan  __asm volatile ("int $0x80"
90169695Skan		  : "=a" (res)
91169695Skan		  : "0"(SYS_futex), "b" (addr), "c"(op),
92169695Skan		    "d"(val), "S"(0)
93169695Skan		  : "memory");
94169695Skan}
95169695Skan
96169695Skan# endif /* __PIC__ */
97169695Skan
98169695Skanstatic inline void
99169695Skanfutex_wait (int *addr, int val)
100169695Skan{
101169695Skan  sys_futex0 (addr, FUTEX_WAIT, val);
102169695Skan}
103169695Skan
104169695Skanstatic inline void
105169695Skanfutex_wake (int *addr, int count)
106169695Skan{
107169695Skan  sys_futex0 (addr, FUTEX_WAKE, count);
108169695Skan}
109169695Skan
110169695Skan#endif /* __LP64__ */
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