Daily bump.
[official-gcc.git] / libgomp / sections.c
blobd7b8c67745a3f2863268fdcb32cc3c11416dd328
1 /* Copyright (C) 2005-2021 Free Software Foundation, Inc.
2 Contributed by Richard Henderson <rth@redhat.com>.
4 This file is part of the GNU Offloading and Multi Processing Library
5 (libgomp).
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.
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.
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.
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/>. */
26 /* This file handles the SECTIONS construct. */
28 #include "libgomp.h"
29 #include <string.h>
32 ialias_redirect (GOMP_taskgroup_reduction_register)
34 /* Initialize the given work share construct from the given arguments. */
36 static inline void
37 gomp_sections_init (struct gomp_work_share *ws, unsigned count)
39 ws->sched = GFS_DYNAMIC;
40 ws->chunk_size = 1;
41 ws->end = count + 1L;
42 ws->incr = 1;
43 ws->next = 1;
44 #ifdef HAVE_SYNC_BUILTINS
45 /* Prepare things to make each iteration faster. */
46 if (sizeof (long) > sizeof (unsigned))
47 ws->mode = 1;
48 else
50 struct gomp_thread *thr = gomp_thread ();
51 struct gomp_team *team = thr->ts.team;
52 long nthreads = team ? team->nthreads : 1;
54 ws->mode = ((nthreads | ws->end)
55 < 1UL << (sizeof (long) * __CHAR_BIT__ / 2 - 1));
57 #else
58 ws->mode = 0;
59 #endif
62 /* This routine is called when first encountering a sections construct
63 that is not bound directly to a parallel construct. The first thread
64 that arrives will create the work-share construct; subsequent threads
65 will see the construct exists and allocate work from it.
67 COUNT is the number of sections in this construct.
69 Returns the 1-based section number for this thread to perform, or 0 if
70 all work was assigned to other threads prior to this thread's arrival. */
72 unsigned
73 GOMP_sections_start (unsigned count)
75 struct gomp_thread *thr = gomp_thread ();
76 long s, e, ret;
78 if (gomp_work_share_start (0))
80 gomp_sections_init (thr->ts.work_share, count);
81 gomp_work_share_init_done ();
84 #ifdef HAVE_SYNC_BUILTINS
85 if (gomp_iter_dynamic_next (&s, &e))
86 ret = s;
87 else
88 ret = 0;
89 #else
90 gomp_mutex_lock (&thr->ts.work_share->lock);
91 if (gomp_iter_dynamic_next_locked (&s, &e))
92 ret = s;
93 else
94 ret = 0;
95 gomp_mutex_unlock (&thr->ts.work_share->lock);
96 #endif
98 return ret;
101 unsigned
102 GOMP_sections2_start (unsigned count, uintptr_t *reductions, void **mem)
104 struct gomp_thread *thr = gomp_thread ();
105 long s, e, ret;
107 if (reductions)
108 gomp_workshare_taskgroup_start ();
109 if (gomp_work_share_start (0))
111 gomp_sections_init (thr->ts.work_share, count);
112 if (reductions)
114 GOMP_taskgroup_reduction_register (reductions);
115 thr->task->taskgroup->workshare = true;
116 thr->ts.work_share->task_reductions = reductions;
118 if (mem)
120 uintptr_t size = (uintptr_t) *mem;
121 #define INLINE_ORDERED_TEAM_IDS_OFF \
122 ((offsetof (struct gomp_work_share, inline_ordered_team_ids) \
123 + __alignof__ (long long) - 1) & ~(__alignof__ (long long) - 1))
124 if (size > (sizeof (struct gomp_work_share)
125 - INLINE_ORDERED_TEAM_IDS_OFF))
126 *mem
127 = (void *) (thr->ts.work_share->ordered_team_ids
128 = gomp_malloc_cleared (size));
129 else
130 *mem = memset (((char *) thr->ts.work_share)
131 + INLINE_ORDERED_TEAM_IDS_OFF, '\0', size);
133 gomp_work_share_init_done ();
135 else
137 if (reductions)
139 uintptr_t *first_reductions = thr->ts.work_share->task_reductions;
140 gomp_workshare_task_reduction_register (reductions,
141 first_reductions);
143 if (mem)
145 if ((offsetof (struct gomp_work_share, inline_ordered_team_ids)
146 & (__alignof__ (long long) - 1)) == 0)
147 *mem = (void *) thr->ts.work_share->ordered_team_ids;
148 else
150 uintptr_t p = (uintptr_t) thr->ts.work_share->ordered_team_ids;
151 p += __alignof__ (long long) - 1;
152 p &= ~(__alignof__ (long long) - 1);
153 *mem = (void *) p;
158 #ifdef HAVE_SYNC_BUILTINS
159 if (gomp_iter_dynamic_next (&s, &e))
160 ret = s;
161 else
162 ret = 0;
163 #else
164 gomp_mutex_lock (&thr->ts.work_share->lock);
165 if (gomp_iter_dynamic_next_locked (&s, &e))
166 ret = s;
167 else
168 ret = 0;
169 gomp_mutex_unlock (&thr->ts.work_share->lock);
170 #endif
172 return ret;
175 /* This routine is called when the thread completes processing of the
176 section currently assigned to it. If the work-share construct is
177 bound directly to a parallel construct, then the construct may have
178 been set up before the parallel. In which case, this may be the
179 first iteration for the thread.
181 Returns the 1-based section number for this thread to perform, or 0 if
182 all work was assigned to other threads prior to this thread's arrival. */
184 unsigned
185 GOMP_sections_next (void)
187 long s, e, ret;
189 #ifdef HAVE_SYNC_BUILTINS
190 if (gomp_iter_dynamic_next (&s, &e))
191 ret = s;
192 else
193 ret = 0;
194 #else
195 struct gomp_thread *thr = gomp_thread ();
197 gomp_mutex_lock (&thr->ts.work_share->lock);
198 if (gomp_iter_dynamic_next_locked (&s, &e))
199 ret = s;
200 else
201 ret = 0;
202 gomp_mutex_unlock (&thr->ts.work_share->lock);
203 #endif
205 return ret;
208 /* This routine pre-initializes a work-share construct to avoid one
209 synchronization once we get into the loop. */
211 void
212 GOMP_parallel_sections_start (void (*fn) (void *), void *data,
213 unsigned num_threads, unsigned count)
215 struct gomp_team *team;
217 num_threads = gomp_resolve_num_threads (num_threads, count);
218 team = gomp_new_team (num_threads);
219 gomp_sections_init (&team->work_shares[0], count);
220 gomp_team_start (fn, data, num_threads, 0, team, NULL);
223 ialias_redirect (GOMP_parallel_end)
225 void
226 GOMP_parallel_sections (void (*fn) (void *), void *data,
227 unsigned num_threads, unsigned count, unsigned flags)
229 struct gomp_team *team;
231 num_threads = gomp_resolve_num_threads (num_threads, count);
232 team = gomp_new_team (num_threads);
233 gomp_sections_init (&team->work_shares[0], count);
234 gomp_team_start (fn, data, num_threads, flags, team, NULL);
235 fn (data);
236 GOMP_parallel_end ();
239 /* The GOMP_section_end* routines are called after the thread is told
240 that all sections are complete. The first two versions synchronize
241 all threads; the nowait version does not. */
243 void
244 GOMP_sections_end (void)
246 gomp_work_share_end ();
249 bool
250 GOMP_sections_end_cancel (void)
252 return gomp_work_share_end_cancel ();
255 void
256 GOMP_sections_end_nowait (void)
258 gomp_work_share_end_nowait ();