1 /* Copyright (C) 2005, 2008, 2009 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 General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 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 General Public License for 14 more details. 15 16 Under Section 7 of GPL version 3, you are granted additional 17 permissions described in the GCC Runtime Library Exception, version 18 3.1, as published by the Free Software Foundation. 19 20 You should have received a copy of the GNU General Public License and 21 a copy of the GCC Runtime Library Exception along with this program; 22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 <http://www.gnu.org/licenses/>. */ 24 25 /* This file handles the LOOP (FOR/DO) construct. */ 26 27 #include <limits.h> 28 #include <stdlib.h> 29 #include "libgomp.h" 30 31 typedef unsigned long long gomp_ull; 32 33 /* Initialize the given work share construct from the given arguments. */ 34 35 static inline void 36 gomp_loop_ull_init (struct gomp_work_share *ws, bool up, gomp_ull start, 37 gomp_ull end, gomp_ull incr, enum gomp_schedule_type sched, 38 gomp_ull chunk_size) 39 { 40 ws->sched = sched; 41 ws->chunk_size_ull = chunk_size; 42 /* Canonicalize loops that have zero iterations to ->next == ->end. */ 43 ws->end_ull = ((up && start > end) || (!up && start < end)) 44 ? start : end; 45 ws->incr_ull = incr; 46 ws->next_ull = start; 47 ws->mode = 0; 48 if (sched == GFS_DYNAMIC) 49 { 50 ws->chunk_size_ull *= incr; 51 52 #if defined HAVE_SYNC_BUILTINS && defined __LP64__ 53 { 54 /* For dynamic scheduling prepare things to make each iteration 55 faster. */ 56 struct gomp_thread *thr = gomp_thread (); 57 struct gomp_team *team = thr->ts.team; 58 long nthreads = team ? team->nthreads : 1; 59 60 if (__builtin_expect (up, 1)) 61 { 62 /* Cheap overflow protection. */ 63 if (__builtin_expect ((nthreads | ws->chunk_size_ull) 64 < 1ULL << (sizeof (gomp_ull) 65 * __CHAR_BIT__ / 2 - 1), 1)) 66 ws->mode = ws->end_ull < (__LONG_LONG_MAX__ * 2ULL + 1 67 - (nthreads + 1) * ws->chunk_size_ull); 68 } 69 /* Cheap overflow protection. */ 70 else if (__builtin_expect ((nthreads | -ws->chunk_size_ull) 71 < 1ULL << (sizeof (gomp_ull) 72 * __CHAR_BIT__ / 2 - 1), 1)) 73 ws->mode = ws->end_ull > ((nthreads + 1) * -ws->chunk_size_ull 74 - (__LONG_LONG_MAX__ * 2ULL + 1)); 75 } 76 #endif 77 } 78 if (!up) 79 ws->mode |= 2; 80 } 81 82 /* The *_start routines are called when first encountering a loop construct 83 that is not bound directly to a parallel construct. The first thread 84 that arrives will create the work-share construct; subsequent threads 85 will see the construct exists and allocate work from it. 86 87 START, END, INCR are the bounds of the loop; due to the restrictions of 88 OpenMP, these values must be the same in every thread. This is not 89 verified (nor is it entirely verifiable, since START is not necessarily 90 retained intact in the work-share data structure). CHUNK_SIZE is the 91 scheduling parameter; again this must be identical in all threads. 92 93 Returns true if there's any work for this thread to perform. If so, 94 *ISTART and *IEND are filled with the bounds of the iteration block 95 allocated to this thread. Returns false if all work was assigned to 96 other threads prior to this thread's arrival. */ 97 98 static bool 99 gomp_loop_ull_static_start (bool up, gomp_ull start, gomp_ull end, 100 gomp_ull incr, gomp_ull chunk_size, 101 gomp_ull *istart, gomp_ull *iend) 102 { 103 struct gomp_thread *thr = gomp_thread (); 104 105 thr->ts.static_trip = 0; 106 if (gomp_work_share_start (false)) 107 { 108 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 109 GFS_STATIC, chunk_size); 110 gomp_work_share_init_done (); 111 } 112 113 return !gomp_iter_ull_static_next (istart, iend); 114 } 115 116 static bool 117 gomp_loop_ull_dynamic_start (bool up, gomp_ull start, gomp_ull end, 118 gomp_ull incr, gomp_ull chunk_size, 119 gomp_ull *istart, gomp_ull *iend) 120 { 121 struct gomp_thread *thr = gomp_thread (); 122 bool ret; 123 124 if (gomp_work_share_start (false)) 125 { 126 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 127 GFS_DYNAMIC, chunk_size); 128 gomp_work_share_init_done (); 129 } 130 131 #if defined HAVE_SYNC_BUILTINS && defined __LP64__ 132 ret = gomp_iter_ull_dynamic_next (istart, iend); 133 #else 134 gomp_mutex_lock (&thr->ts.work_share->lock); 135 ret = gomp_iter_ull_dynamic_next_locked (istart, iend); 136 gomp_mutex_unlock (&thr->ts.work_share->lock); 137 #endif 138 139 return ret; 140 } 141 142 static bool 143 gomp_loop_ull_guided_start (bool up, gomp_ull start, gomp_ull end, 144 gomp_ull incr, gomp_ull chunk_size, 145 gomp_ull *istart, gomp_ull *iend) 146 { 147 struct gomp_thread *thr = gomp_thread (); 148 bool ret; 149 150 if (gomp_work_share_start (false)) 151 { 152 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 153 GFS_GUIDED, chunk_size); 154 gomp_work_share_init_done (); 155 } 156 157 #if defined HAVE_SYNC_BUILTINS && defined __LP64__ 158 ret = gomp_iter_ull_guided_next (istart, iend); 159 #else 160 gomp_mutex_lock (&thr->ts.work_share->lock); 161 ret = gomp_iter_ull_guided_next_locked (istart, iend); 162 gomp_mutex_unlock (&thr->ts.work_share->lock); 163 #endif 164 165 return ret; 166 } 167 168 bool 169 GOMP_loop_ull_runtime_start (bool up, gomp_ull start, gomp_ull end, 170 gomp_ull incr, gomp_ull *istart, gomp_ull *iend) 171 { 172 struct gomp_task_icv *icv = gomp_icv (false); 173 switch (icv->run_sched_var) 174 { 175 case GFS_STATIC: 176 return gomp_loop_ull_static_start (up, start, end, incr, 177 icv->run_sched_modifier, 178 istart, iend); 179 case GFS_DYNAMIC: 180 return gomp_loop_ull_dynamic_start (up, start, end, incr, 181 icv->run_sched_modifier, 182 istart, iend); 183 case GFS_GUIDED: 184 return gomp_loop_ull_guided_start (up, start, end, incr, 185 icv->run_sched_modifier, 186 istart, iend); 187 case GFS_AUTO: 188 /* For now map to schedule(static), later on we could play with feedback 189 driven choice. */ 190 return gomp_loop_ull_static_start (up, start, end, incr, 191 0, istart, iend); 192 default: 193 abort (); 194 } 195 } 196 197 /* The *_ordered_*_start routines are similar. The only difference is that 198 this work-share construct is initialized to expect an ORDERED section. */ 199 200 static bool 201 gomp_loop_ull_ordered_static_start (bool up, gomp_ull start, gomp_ull end, 202 gomp_ull incr, gomp_ull chunk_size, 203 gomp_ull *istart, gomp_ull *iend) 204 { 205 struct gomp_thread *thr = gomp_thread (); 206 207 thr->ts.static_trip = 0; 208 if (gomp_work_share_start (true)) 209 { 210 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 211 GFS_STATIC, chunk_size); 212 gomp_ordered_static_init (); 213 gomp_work_share_init_done (); 214 } 215 216 return !gomp_iter_ull_static_next (istart, iend); 217 } 218 219 static bool 220 gomp_loop_ull_ordered_dynamic_start (bool up, gomp_ull start, gomp_ull end, 221 gomp_ull incr, gomp_ull chunk_size, 222 gomp_ull *istart, gomp_ull *iend) 223 { 224 struct gomp_thread *thr = gomp_thread (); 225 bool ret; 226 227 if (gomp_work_share_start (true)) 228 { 229 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 230 GFS_DYNAMIC, chunk_size); 231 gomp_mutex_lock (&thr->ts.work_share->lock); 232 gomp_work_share_init_done (); 233 } 234 else 235 gomp_mutex_lock (&thr->ts.work_share->lock); 236 237 ret = gomp_iter_ull_dynamic_next_locked (istart, iend); 238 if (ret) 239 gomp_ordered_first (); 240 gomp_mutex_unlock (&thr->ts.work_share->lock); 241 242 return ret; 243 } 244 245 static bool 246 gomp_loop_ull_ordered_guided_start (bool up, gomp_ull start, gomp_ull end, 247 gomp_ull incr, gomp_ull chunk_size, 248 gomp_ull *istart, gomp_ull *iend) 249 { 250 struct gomp_thread *thr = gomp_thread (); 251 bool ret; 252 253 if (gomp_work_share_start (true)) 254 { 255 gomp_loop_ull_init (thr->ts.work_share, up, start, end, incr, 256 GFS_GUIDED, chunk_size); 257 gomp_mutex_lock (&thr->ts.work_share->lock); 258 gomp_work_share_init_done (); 259 } 260 else 261 gomp_mutex_lock (&thr->ts.work_share->lock); 262 263 ret = gomp_iter_ull_guided_next_locked (istart, iend); 264 if (ret) 265 gomp_ordered_first (); 266 gomp_mutex_unlock (&thr->ts.work_share->lock); 267 268 return ret; 269 } 270 271 bool 272 GOMP_loop_ull_ordered_runtime_start (bool up, gomp_ull start, gomp_ull end, 273 gomp_ull incr, gomp_ull *istart, 274 gomp_ull *iend) 275 { 276 struct gomp_task_icv *icv = gomp_icv (false); 277 switch (icv->run_sched_var) 278 { 279 case GFS_STATIC: 280 return gomp_loop_ull_ordered_static_start (up, start, end, incr, 281 icv->run_sched_modifier, 282 istart, iend); 283 case GFS_DYNAMIC: 284 return gomp_loop_ull_ordered_dynamic_start (up, start, end, incr, 285 icv->run_sched_modifier, 286 istart, iend); 287 case GFS_GUIDED: 288 return gomp_loop_ull_ordered_guided_start (up, start, end, incr, 289 icv->run_sched_modifier, 290 istart, iend); 291 case GFS_AUTO: 292 /* For now map to schedule(static), later on we could play with feedback 293 driven choice. */ 294 return gomp_loop_ull_ordered_static_start (up, start, end, incr, 295 0, istart, iend); 296 default: 297 abort (); 298 } 299 } 300 301 /* The *_next routines are called when the thread completes processing of 302 the iteration block currently assigned to it. If the work-share 303 construct is bound directly to a parallel construct, then the iteration 304 bounds may have been set up before the parallel. In which case, this 305 may be the first iteration for the thread. 306 307 Returns true if there is work remaining to be performed; *ISTART and 308 *IEND are filled with a new iteration block. Returns false if all work 309 has been assigned. */ 310 311 static bool 312 gomp_loop_ull_static_next (gomp_ull *istart, gomp_ull *iend) 313 { 314 return !gomp_iter_ull_static_next (istart, iend); 315 } 316 317 static bool 318 gomp_loop_ull_dynamic_next (gomp_ull *istart, gomp_ull *iend) 319 { 320 bool ret; 321 322 #if defined HAVE_SYNC_BUILTINS && defined __LP64__ 323 ret = gomp_iter_ull_dynamic_next (istart, iend); 324 #else 325 struct gomp_thread *thr = gomp_thread (); 326 gomp_mutex_lock (&thr->ts.work_share->lock); 327 ret = gomp_iter_ull_dynamic_next_locked (istart, iend); 328 gomp_mutex_unlock (&thr->ts.work_share->lock); 329 #endif 330 331 return ret; 332 } 333 334 static bool 335 gomp_loop_ull_guided_next (gomp_ull *istart, gomp_ull *iend) 336 { 337 bool ret; 338 339 #if defined HAVE_SYNC_BUILTINS && defined __LP64__ 340 ret = gomp_iter_ull_guided_next (istart, iend); 341 #else 342 struct gomp_thread *thr = gomp_thread (); 343 gomp_mutex_lock (&thr->ts.work_share->lock); 344 ret = gomp_iter_ull_guided_next_locked (istart, iend); 345 gomp_mutex_unlock (&thr->ts.work_share->lock); 346 #endif 347 348 return ret; 349 } 350 351 bool 352 GOMP_loop_ull_runtime_next (gomp_ull *istart, gomp_ull *iend) 353 { 354 struct gomp_thread *thr = gomp_thread (); 355 356 switch (thr->ts.work_share->sched) 357 { 358 case GFS_STATIC: 359 case GFS_AUTO: 360 return gomp_loop_ull_static_next (istart, iend); 361 case GFS_DYNAMIC: 362 return gomp_loop_ull_dynamic_next (istart, iend); 363 case GFS_GUIDED: 364 return gomp_loop_ull_guided_next (istart, iend); 365 default: 366 abort (); 367 } 368 } 369 370 /* The *_ordered_*_next routines are called when the thread completes 371 processing of the iteration block currently assigned to it. 372 373 Returns true if there is work remaining to be performed; *ISTART and 374 *IEND are filled with a new iteration block. Returns false if all work 375 has been assigned. */ 376 377 static bool 378 gomp_loop_ull_ordered_static_next (gomp_ull *istart, gomp_ull *iend) 379 { 380 struct gomp_thread *thr = gomp_thread (); 381 int test; 382 383 gomp_ordered_sync (); 384 gomp_mutex_lock (&thr->ts.work_share->lock); 385 test = gomp_iter_ull_static_next (istart, iend); 386 if (test >= 0) 387 gomp_ordered_static_next (); 388 gomp_mutex_unlock (&thr->ts.work_share->lock); 389 390 return test == 0; 391 } 392 393 static bool 394 gomp_loop_ull_ordered_dynamic_next (gomp_ull *istart, gomp_ull *iend) 395 { 396 struct gomp_thread *thr = gomp_thread (); 397 bool ret; 398 399 gomp_ordered_sync (); 400 gomp_mutex_lock (&thr->ts.work_share->lock); 401 ret = gomp_iter_ull_dynamic_next_locked (istart, iend); 402 if (ret) 403 gomp_ordered_next (); 404 else 405 gomp_ordered_last (); 406 gomp_mutex_unlock (&thr->ts.work_share->lock); 407 408 return ret; 409 } 410 411 static bool 412 gomp_loop_ull_ordered_guided_next (gomp_ull *istart, gomp_ull *iend) 413 { 414 struct gomp_thread *thr = gomp_thread (); 415 bool ret; 416 417 gomp_ordered_sync (); 418 gomp_mutex_lock (&thr->ts.work_share->lock); 419 ret = gomp_iter_ull_guided_next_locked (istart, iend); 420 if (ret) 421 gomp_ordered_next (); 422 else 423 gomp_ordered_last (); 424 gomp_mutex_unlock (&thr->ts.work_share->lock); 425 426 return ret; 427 } 428 429 bool 430 GOMP_loop_ull_ordered_runtime_next (gomp_ull *istart, gomp_ull *iend) 431 { 432 struct gomp_thread *thr = gomp_thread (); 433 434 switch (thr->ts.work_share->sched) 435 { 436 case GFS_STATIC: 437 case GFS_AUTO: 438 return gomp_loop_ull_ordered_static_next (istart, iend); 439 case GFS_DYNAMIC: 440 return gomp_loop_ull_ordered_dynamic_next (istart, iend); 441 case GFS_GUIDED: 442 return gomp_loop_ull_ordered_guided_next (istart, iend); 443 default: 444 abort (); 445 } 446 } 447 448 /* We use static functions above so that we're sure that the "runtime" 449 function can defer to the proper routine without interposition. We 450 export the static function with a strong alias when possible, or with 451 a wrapper function otherwise. */ 452 453 #ifdef HAVE_ATTRIBUTE_ALIAS 454 extern __typeof(gomp_loop_ull_static_start) GOMP_loop_ull_static_start 455 __attribute__((alias ("gomp_loop_ull_static_start"))); 456 extern __typeof(gomp_loop_ull_dynamic_start) GOMP_loop_ull_dynamic_start 457 __attribute__((alias ("gomp_loop_ull_dynamic_start"))); 458 extern __typeof(gomp_loop_ull_guided_start) GOMP_loop_ull_guided_start 459 __attribute__((alias ("gomp_loop_ull_guided_start"))); 460 461 extern __typeof(gomp_loop_ull_ordered_static_start) GOMP_loop_ull_ordered_static_start 462 __attribute__((alias ("gomp_loop_ull_ordered_static_start"))); 463 extern __typeof(gomp_loop_ull_ordered_dynamic_start) GOMP_loop_ull_ordered_dynamic_start 464 __attribute__((alias ("gomp_loop_ull_ordered_dynamic_start"))); 465 extern __typeof(gomp_loop_ull_ordered_guided_start) GOMP_loop_ull_ordered_guided_start 466 __attribute__((alias ("gomp_loop_ull_ordered_guided_start"))); 467 468 extern __typeof(gomp_loop_ull_static_next) GOMP_loop_ull_static_next 469 __attribute__((alias ("gomp_loop_ull_static_next"))); 470 extern __typeof(gomp_loop_ull_dynamic_next) GOMP_loop_ull_dynamic_next 471 __attribute__((alias ("gomp_loop_ull_dynamic_next"))); 472 extern __typeof(gomp_loop_ull_guided_next) GOMP_loop_ull_guided_next 473 __attribute__((alias ("gomp_loop_ull_guided_next"))); 474 475 extern __typeof(gomp_loop_ull_ordered_static_next) GOMP_loop_ull_ordered_static_next 476 __attribute__((alias ("gomp_loop_ull_ordered_static_next"))); 477 extern __typeof(gomp_loop_ull_ordered_dynamic_next) GOMP_loop_ull_ordered_dynamic_next 478 __attribute__((alias ("gomp_loop_ull_ordered_dynamic_next"))); 479 extern __typeof(gomp_loop_ull_ordered_guided_next) GOMP_loop_ull_ordered_guided_next 480 __attribute__((alias ("gomp_loop_ull_ordered_guided_next"))); 481 #else 482 bool 483 GOMP_loop_ull_static_start (bool up, gomp_ull start, gomp_ull end, 484 gomp_ull incr, gomp_ull chunk_size, 485 gomp_ull *istart, gomp_ull *iend) 486 { 487 return gomp_loop_ull_static_start (up, start, end, incr, chunk_size, istart, 488 iend); 489 } 490 491 bool 492 GOMP_loop_ull_dynamic_start (bool up, gomp_ull start, gomp_ull end, 493 gomp_ull incr, gomp_ull chunk_size, 494 gomp_ull *istart, gomp_ull *iend) 495 { 496 return gomp_loop_ull_dynamic_start (up, start, end, incr, chunk_size, istart, 497 iend); 498 } 499 500 bool 501 GOMP_loop_ull_guided_start (bool up, gomp_ull start, gomp_ull end, 502 gomp_ull incr, gomp_ull chunk_size, 503 gomp_ull *istart, gomp_ull *iend) 504 { 505 return gomp_loop_ull_guided_start (up, start, end, incr, chunk_size, istart, 506 iend); 507 } 508 509 bool 510 GOMP_loop_ull_ordered_static_start (bool up, gomp_ull start, gomp_ull end, 511 gomp_ull incr, gomp_ull chunk_size, 512 gomp_ull *istart, gomp_ull *iend) 513 { 514 return gomp_loop_ull_ordered_static_start (up, start, end, incr, chunk_size, 515 istart, iend); 516 } 517 518 bool 519 GOMP_loop_ull_ordered_dynamic_start (bool up, gomp_ull start, gomp_ull end, 520 gomp_ull incr, gomp_ull chunk_size, 521 gomp_ull *istart, gomp_ull *iend) 522 { 523 return gomp_loop_ull_ordered_dynamic_start (up, start, end, incr, chunk_size, 524 istart, iend); 525 } 526 527 bool 528 GOMP_loop_ull_ordered_guided_start (bool up, gomp_ull start, gomp_ull end, 529 gomp_ull incr, gomp_ull chunk_size, 530 gomp_ull *istart, gomp_ull *iend) 531 { 532 return gomp_loop_ull_ordered_guided_start (up, start, end, incr, chunk_size, 533 istart, iend); 534 } 535 536 bool 537 GOMP_loop_ull_static_next (gomp_ull *istart, gomp_ull *iend) 538 { 539 return gomp_loop_ull_static_next (istart, iend); 540 } 541 542 bool 543 GOMP_loop_ull_dynamic_next (gomp_ull *istart, gomp_ull *iend) 544 { 545 return gomp_loop_ull_dynamic_next (istart, iend); 546 } 547 548 bool 549 GOMP_loop_ull_guided_next (gomp_ull *istart, gomp_ull *iend) 550 { 551 return gomp_loop_ull_guided_next (istart, iend); 552 } 553 554 bool 555 GOMP_loop_ull_ordered_static_next (gomp_ull *istart, gomp_ull *iend) 556 { 557 return gomp_loop_ull_ordered_static_next (istart, iend); 558 } 559 560 bool 561 GOMP_loop_ull_ordered_dynamic_next (gomp_ull *istart, gomp_ull *iend) 562 { 563 return gomp_loop_ull_ordered_dynamic_next (istart, iend); 564 } 565 566 bool 567 GOMP_loop_ull_ordered_guided_next (gomp_ull *istart, gomp_ull *iend) 568 { 569 return gomp_loop_ull_ordered_guided_next (istart, iend); 570 } 571 #endif 572