1 /* Copyright (C) 2005-2021 Free Software Foundation, Inc.
2 Contributed by Jakub Jelinek <jakub@redhat.com>.
3
4 This file is part of the GNU Offloading and Multi Processing Library
5 (libgomp).
6
7 Libgomp is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14 FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 more details.
16
17 Under Section 7 of GPL version 3, you are granted additional
18 permissions described in the GCC Runtime Library Exception, version
19 3.1, as published by the Free Software Foundation.
20
21 You should have received a copy of the GNU General Public License and
22 a copy of the GCC Runtime Library Exception along with this program;
23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 <http://www.gnu.org/licenses/>. */
25
26 /* Provide target-specific access to the futex system call. */
27
28 #include <sys/syscall.h>
29
30 static inline long
sys_futex0(int * addr,int op,int val)31 sys_futex0 (int *addr, int op, int val)
32 {
33 register long int g1 __asm__ ("g1");
34 register long int o0 __asm__ ("o0");
35 register long int o1 __asm__ ("o1");
36 register long int o2 __asm__ ("o2");
37 register long int o3 __asm__ ("o3");
38
39 g1 = SYS_futex;
40 o0 = (long) addr;
41 o1 = op;
42 o2 = val;
43 o3 = 0;
44
45 #ifdef __arch64__
46 # define SYSCALL_STRING "ta\t0x6d; bcs,a,pt %%xcc, 1f; sub %%g0, %%o0, %%o0; 1:"
47 #else
48 # define SYSCALL_STRING "ta\t0x10; bcs,a 1f; sub %%g0, %%o0, %%o0; 1:"
49 #endif
50
51 __asm volatile (SYSCALL_STRING
52 : "=r" (g1), "=r" (o0)
53 : "0" (g1), "1" (o0), "r" (o1), "r" (o2), "r" (o3)
54 : "g2", "g3", "g4", "g5", "g6",
55 "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
56 "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
57 "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
58 "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
59 #ifdef __arch64__
60 "f32", "f34", "f36", "f38", "f40", "f42", "f44", "f46",
61 "f48", "f50", "f52", "f54", "f56", "f58", "f60", "f62",
62 #endif
63 "cc", "memory");
64 return o0;
65 }
66
67 static inline void
futex_wait(int * addr,int val)68 futex_wait (int *addr, int val)
69 {
70 long err = sys_futex0 (addr, gomp_futex_wait, val);
71 if (__builtin_expect (err == ENOSYS, 0))
72 {
73 gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
74 gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
75 sys_futex0 (addr, gomp_futex_wait, val);
76 }
77 }
78
79 static inline void
futex_wake(int * addr,int count)80 futex_wake (int *addr, int count)
81 {
82 long err = sys_futex0 (addr, gomp_futex_wake, count);
83 if (__builtin_expect (err == ENOSYS, 0))
84 {
85 gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
86 gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
87 sys_futex0 (addr, gomp_futex_wake, count);
88 }
89 }
90
91 static inline void
cpu_relax(void)92 cpu_relax (void)
93 {
94 __asm volatile ("rd %%ccr, %%g0" : : : "memory");
95 }
96