libgomp.info revision 1.1.1.6
1 This is libgomp.info, produced by makeinfo version 6.4 from 2 libgomp.texi. 3 4 Copyright (C) 2006-2016 Free Software Foundation, Inc. 5 6 Permission is granted to copy, distribute and/or modify this document 7 under the terms of the GNU Free Documentation License, Version 1.3 or 8 any later version published by the Free Software Foundation; with the 9 Invariant Sections being "Funding Free Software", the Front-Cover texts 10 being (a) (see below), and with the Back-Cover Texts being (b) (see 11 below). A copy of the license is included in the section entitled "GNU 12 Free Documentation License". 13 14 (a) The FSF's Front-Cover Text is: 15 16 A GNU Manual 17 18 (b) The FSF's Back-Cover Text is: 19 20 You have freedom to copy and modify this GNU Manual, like GNU 21 software. Copies published by the Free Software Foundation raise funds 22 for GNU development. 23 INFO-DIR-SECTION GNU Libraries 24 START-INFO-DIR-ENTRY 25 * libgomp: (libgomp). GNU Offloading and Multi Processing Runtime Library. 26 END-INFO-DIR-ENTRY 27 28 This manual documents libgomp, the GNU Offloading and Multi 29 Processing Runtime library. This is the GNU implementation of the 30 OpenMP and OpenACC APIs for parallel and accelerator programming in 31 C/C++ and Fortran. 32 33 Published by the Free Software Foundation 51 Franklin Street, Fifth 34 Floor Boston, MA 02110-1301 USA 35 36 Copyright (C) 2006-2016 Free Software Foundation, Inc. 37 38 Permission is granted to copy, distribute and/or modify this document 39 under the terms of the GNU Free Documentation License, Version 1.3 or 40 any later version published by the Free Software Foundation; with the 41 Invariant Sections being "Funding Free Software", the Front-Cover texts 42 being (a) (see below), and with the Back-Cover Texts being (b) (see 43 below). A copy of the license is included in the section entitled "GNU 44 Free Documentation License". 45 46 (a) The FSF's Front-Cover Text is: 47 48 A GNU Manual 49 50 (b) The FSF's Back-Cover Text is: 51 52 You have freedom to copy and modify this GNU Manual, like GNU 53 software. Copies published by the Free Software Foundation raise funds 54 for GNU development. 55 56 57 File: libgomp.info, Node: Top, Next: Enabling OpenMP, Up: (dir) 58 59 Introduction 60 ************ 61 62 This manual documents the usage of libgomp, the GNU Offloading and Multi 63 Processing Runtime Library. This includes the GNU implementation of the 64 OpenMP (http://www.openmp.org) Application Programming Interface (API) 65 for multi-platform shared-memory parallel programming in C/C++ and 66 Fortran, and the GNU implementation of the OpenACC 67 (http://www.openacc.org/) Application Programming Interface (API) for 68 offloading of code to accelerator devices in C/C++ and Fortran. 69 70 Originally, libgomp implemented the GNU OpenMP Runtime Library. 71 Based on this, support for OpenACC and offloading (both OpenACC and 72 OpenMP 4's target construct) has been added later on, and the library's 73 name changed to GNU Offloading and Multi Processing Runtime Library. 74 75 * Menu: 76 77 * Enabling OpenMP:: How to enable OpenMP for your applications. 78 * Runtime Library Routines:: The OpenMP runtime application programming 79 interface. 80 * Environment Variables:: Influencing runtime behavior with environment 81 variables. 82 * Enabling OpenACC:: How to enable OpenACC for your 83 applications. 84 * OpenACC Runtime Library Routines:: The OpenACC runtime application 85 programming interface. 86 * OpenACC Environment Variables:: Influencing OpenACC runtime behavior with 87 environment variables. 88 * CUDA Streams Usage:: Notes on the implementation of 89 asynchronous operations. 90 * OpenACC Library Interoperability:: OpenACC library interoperability with the 91 NVIDIA CUBLAS library. 92 * The libgomp ABI:: Notes on the external ABI presented by libgomp. 93 * Reporting Bugs:: How to report bugs in the GNU Offloading and 94 Multi Processing Runtime Library. 95 * Copying:: GNU general public license says 96 how you can copy and share libgomp. 97 * GNU Free Documentation License:: 98 How you can copy and share this manual. 99 * Funding:: How to help assure continued work for free 100 software. 101 * Library Index:: Index of this documentation. 102 103 104 File: libgomp.info, Node: Enabling OpenMP, Next: Runtime Library Routines, Prev: Top, Up: Top 105 106 1 Enabling OpenMP 107 ***************** 108 109 To activate the OpenMP extensions for C/C++ and Fortran, the 110 compile-time flag '-fopenmp' must be specified. This enables the OpenMP 111 directive '#pragma omp' in C/C++ and '!$omp' directives in free form, 112 'c$omp', '*$omp' and '!$omp' directives in fixed form, '!$' conditional 113 compilation sentinels in free form and 'c$', '*$' and '!$' sentinels in 114 fixed form, for Fortran. The flag also arranges for automatic linking 115 of the OpenMP runtime library (*note Runtime Library Routines::). 116 117 A complete description of all OpenMP directives accepted may be found 118 in the OpenMP Application Program Interface (http://www.openmp.org) 119 manual, version 4.5. 120 121 122 File: libgomp.info, Node: Runtime Library Routines, Next: Environment Variables, Prev: Enabling OpenMP, Up: Top 123 124 2 Runtime Library Routines 125 ************************** 126 127 The runtime routines described here are defined by Section 3 of the 128 OpenMP specification in version 4.5. The routines are structured in 129 following three parts: 130 131 * Menu: 132 133 Control threads, processors and the parallel environment. They have C 134 linkage, and do not throw exceptions. 135 136 * omp_get_active_level:: Number of active parallel regions 137 * omp_get_ancestor_thread_num:: Ancestor thread ID 138 * omp_get_cancellation:: Whether cancellation support is enabled 139 * omp_get_default_device:: Get the default device for target regions 140 * omp_get_dynamic:: Dynamic teams setting 141 * omp_get_level:: Number of parallel regions 142 * omp_get_max_active_levels:: Maximum number of active regions 143 * omp_get_max_task_priority:: Maximum task priority value that can be set 144 * omp_get_max_threads:: Maximum number of threads of parallel region 145 * omp_get_nested:: Nested parallel regions 146 * omp_get_num_devices:: Number of target devices 147 * omp_get_num_procs:: Number of processors online 148 * omp_get_num_teams:: Number of teams 149 * omp_get_num_threads:: Size of the active team 150 * omp_get_proc_bind:: Whether theads may be moved between CPUs 151 * omp_get_schedule:: Obtain the runtime scheduling method 152 * omp_get_team_num:: Get team number 153 * omp_get_team_size:: Number of threads in a team 154 * omp_get_thread_limit:: Maximum number of threads 155 * omp_get_thread_num:: Current thread ID 156 * omp_in_parallel:: Whether a parallel region is active 157 * omp_in_final:: Whether in final or included task region 158 * omp_is_initial_device:: Whether executing on the host device 159 * omp_set_default_device:: Set the default device for target regions 160 * omp_set_dynamic:: Enable/disable dynamic teams 161 * omp_set_max_active_levels:: Limits the number of active parallel regions 162 * omp_set_nested:: Enable/disable nested parallel regions 163 * omp_set_num_threads:: Set upper team size limit 164 * omp_set_schedule:: Set the runtime scheduling method 165 166 Initialize, set, test, unset and destroy simple and nested locks. 167 168 * omp_init_lock:: Initialize simple lock 169 * omp_set_lock:: Wait for and set simple lock 170 * omp_test_lock:: Test and set simple lock if available 171 * omp_unset_lock:: Unset simple lock 172 * omp_destroy_lock:: Destroy simple lock 173 * omp_init_nest_lock:: Initialize nested lock 174 * omp_set_nest_lock:: Wait for and set simple lock 175 * omp_test_nest_lock:: Test and set nested lock if available 176 * omp_unset_nest_lock:: Unset nested lock 177 * omp_destroy_nest_lock:: Destroy nested lock 178 179 Portable, thread-based, wall clock timer. 180 181 * omp_get_wtick:: Get timer precision. 182 * omp_get_wtime:: Elapsed wall clock time. 183 184 185 File: libgomp.info, Node: omp_get_active_level, Next: omp_get_ancestor_thread_num, Up: Runtime Library Routines 186 187 2.1 'omp_get_active_level' - Number of parallel regions 188 ======================================================= 189 190 _Description_: 191 This function returns the nesting level for the active parallel 192 blocks, which enclose the calling call. 193 194 _C/C++_ 195 _Prototype_: 'int omp_get_active_level(void);' 196 197 _Fortran_: 198 _Interface_: 'integer function omp_get_active_level()' 199 200 _See also_: 201 *note omp_get_level::, *note omp_get_max_active_levels::, *note 202 omp_set_max_active_levels:: 203 204 _Reference_: 205 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.20. 206 207 208 File: libgomp.info, Node: omp_get_ancestor_thread_num, Next: omp_get_cancellation, Prev: omp_get_active_level, Up: Runtime Library Routines 209 210 2.2 'omp_get_ancestor_thread_num' - Ancestor thread ID 211 ====================================================== 212 213 _Description_: 214 This function returns the thread identification number for the 215 given nesting level of the current thread. For values of LEVEL 216 outside zero to 'omp_get_level' -1 is returned; if LEVEL is 217 'omp_get_level' the result is identical to 'omp_get_thread_num'. 218 219 _C/C++_ 220 _Prototype_: 'int omp_get_ancestor_thread_num(int level);' 221 222 _Fortran_: 223 _Interface_: 'integer function omp_get_ancestor_thread_num(level)' 224 'integer level' 225 226 _See also_: 227 *note omp_get_level::, *note omp_get_thread_num::, *note 228 omp_get_team_size:: 229 230 _Reference_: 231 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.18. 232 233 234 File: libgomp.info, Node: omp_get_cancellation, Next: omp_get_default_device, Prev: omp_get_ancestor_thread_num, Up: Runtime Library Routines 235 236 2.3 'omp_get_cancellation' - Whether cancellation support is enabled 237 ==================================================================== 238 239 _Description_: 240 This function returns 'true' if cancellation is activated, 'false' 241 otherwise. Here, 'true' and 'false' represent their 242 language-specific counterparts. Unless 'OMP_CANCELLATION' is set 243 true, cancellations are deactivated. 244 245 _C/C++_: 246 _Prototype_: 'int omp_get_cancellation(void);' 247 248 _Fortran_: 249 _Interface_: 'logical function omp_get_cancellation()' 250 251 _See also_: 252 *note OMP_CANCELLATION:: 253 254 _Reference_: 255 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.9. 256 257 258 File: libgomp.info, Node: omp_get_default_device, Next: omp_get_dynamic, Prev: omp_get_cancellation, Up: Runtime Library Routines 259 260 2.4 'omp_get_default_device' - Get the default device for target regions 261 ======================================================================== 262 263 _Description_: 264 Get the default device for target regions without device clause. 265 266 _C/C++_: 267 _Prototype_: 'int omp_get_default_device(void);' 268 269 _Fortran_: 270 _Interface_: 'integer function omp_get_default_device()' 271 272 _See also_: 273 *note OMP_DEFAULT_DEVICE::, *note omp_set_default_device:: 274 275 _Reference_: 276 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.30. 277 278 279 File: libgomp.info, Node: omp_get_dynamic, Next: omp_get_level, Prev: omp_get_default_device, Up: Runtime Library Routines 280 281 2.5 'omp_get_dynamic' - Dynamic teams setting 282 ============================================= 283 284 _Description_: 285 This function returns 'true' if enabled, 'false' otherwise. Here, 286 'true' and 'false' represent their language-specific counterparts. 287 288 The dynamic team setting may be initialized at startup by the 289 'OMP_DYNAMIC' environment variable or at runtime using 290 'omp_set_dynamic'. If undefined, dynamic adjustment is disabled by 291 default. 292 293 _C/C++_: 294 _Prototype_: 'int omp_get_dynamic(void);' 295 296 _Fortran_: 297 _Interface_: 'logical function omp_get_dynamic()' 298 299 _See also_: 300 *note omp_set_dynamic::, *note OMP_DYNAMIC:: 301 302 _Reference_: 303 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.8. 304 305 306 File: libgomp.info, Node: omp_get_level, Next: omp_get_max_active_levels, Prev: omp_get_dynamic, Up: Runtime Library Routines 307 308 2.6 'omp_get_level' - Obtain the current nesting level 309 ====================================================== 310 311 _Description_: 312 This function returns the nesting level for the parallel blocks, 313 which enclose the calling call. 314 315 _C/C++_ 316 _Prototype_: 'int omp_get_level(void);' 317 318 _Fortran_: 319 _Interface_: 'integer function omp_level()' 320 321 _See also_: 322 *note omp_get_active_level:: 323 324 _Reference_: 325 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.17. 326 327 328 File: libgomp.info, Node: omp_get_max_active_levels, Next: omp_get_max_task_priority, Prev: omp_get_level, Up: Runtime Library Routines 329 330 2.7 'omp_get_max_active_levels' - Maximum number of active regions 331 ================================================================== 332 333 _Description_: 334 This function obtains the maximum allowed number of nested, active 335 parallel regions. 336 337 _C/C++_ 338 _Prototype_: 'int omp_get_max_active_levels(void);' 339 340 _Fortran_: 341 _Interface_: 'integer function omp_get_max_active_levels()' 342 343 _See also_: 344 *note omp_set_max_active_levels::, *note omp_get_active_level:: 345 346 _Reference_: 347 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.16. 348 349 350 File: libgomp.info, Node: omp_get_max_task_priority, Next: omp_get_max_threads, Prev: omp_get_max_active_levels, Up: Runtime Library Routines 351 352 2.8 'omp_get_max_task_priority' - Maximum priority value 353 ======================================================== 354 355 that can be set for tasks. 356 _Description_: 357 This function obtains the maximum allowed priority number for 358 tasks. 359 360 _C/C++_ 361 _Prototype_: 'int omp_get_max_task_priority(void);' 362 363 _Fortran_: 364 _Interface_: 'integer function omp_get_max_task_priority()' 365 366 _Reference_: 367 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.29. 368 369 370 File: libgomp.info, Node: omp_get_max_threads, Next: omp_get_nested, Prev: omp_get_max_task_priority, Up: Runtime Library Routines 371 372 2.9 'omp_get_max_threads' - Maximum number of threads of parallel region 373 ======================================================================== 374 375 _Description_: 376 Return the maximum number of threads used for the current parallel 377 region that does not use the clause 'num_threads'. 378 379 _C/C++_: 380 _Prototype_: 'int omp_get_max_threads(void);' 381 382 _Fortran_: 383 _Interface_: 'integer function omp_get_max_threads()' 384 385 _See also_: 386 *note omp_set_num_threads::, *note omp_set_dynamic::, *note 387 omp_get_thread_limit:: 388 389 _Reference_: 390 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.3. 391 392 393 File: libgomp.info, Node: omp_get_nested, Next: omp_get_num_devices, Prev: omp_get_max_threads, Up: Runtime Library Routines 394 395 2.10 'omp_get_nested' - Nested parallel regions 396 =============================================== 397 398 _Description_: 399 This function returns 'true' if nested parallel regions are 400 enabled, 'false' otherwise. Here, 'true' and 'false' represent 401 their language-specific counterparts. 402 403 Nested parallel regions may be initialized at startup by the 404 'OMP_NESTED' environment variable or at runtime using 405 'omp_set_nested'. If undefined, nested parallel regions are 406 disabled by default. 407 408 _C/C++_: 409 _Prototype_: 'int omp_get_nested(void);' 410 411 _Fortran_: 412 _Interface_: 'logical function omp_get_nested()' 413 414 _See also_: 415 *note omp_set_nested::, *note OMP_NESTED:: 416 417 _Reference_: 418 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.11. 419 420 421 File: libgomp.info, Node: omp_get_num_devices, Next: omp_get_num_procs, Prev: omp_get_nested, Up: Runtime Library Routines 422 423 2.11 'omp_get_num_devices' - Number of target devices 424 ===================================================== 425 426 _Description_: 427 Returns the number of target devices. 428 429 _C/C++_: 430 _Prototype_: 'int omp_get_num_devices(void);' 431 432 _Fortran_: 433 _Interface_: 'integer function omp_get_num_devices()' 434 435 _Reference_: 436 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.31. 437 438 439 File: libgomp.info, Node: omp_get_num_procs, Next: omp_get_num_teams, Prev: omp_get_num_devices, Up: Runtime Library Routines 440 441 2.12 'omp_get_num_procs' - Number of processors online 442 ====================================================== 443 444 _Description_: 445 Returns the number of processors online on that device. 446 447 _C/C++_: 448 _Prototype_: 'int omp_get_num_procs(void);' 449 450 _Fortran_: 451 _Interface_: 'integer function omp_get_num_procs()' 452 453 _Reference_: 454 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.5. 455 456 457 File: libgomp.info, Node: omp_get_num_teams, Next: omp_get_num_threads, Prev: omp_get_num_procs, Up: Runtime Library Routines 458 459 2.13 'omp_get_num_teams' - Number of teams 460 ========================================== 461 462 _Description_: 463 Returns the number of teams in the current team region. 464 465 _C/C++_: 466 _Prototype_: 'int omp_get_num_teams(void);' 467 468 _Fortran_: 469 _Interface_: 'integer function omp_get_num_teams()' 470 471 _Reference_: 472 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.32. 473 474 475 File: libgomp.info, Node: omp_get_num_threads, Next: omp_get_proc_bind, Prev: omp_get_num_teams, Up: Runtime Library Routines 476 477 2.14 'omp_get_num_threads' - Size of the active team 478 ==================================================== 479 480 _Description_: 481 Returns the number of threads in the current team. In a sequential 482 section of the program 'omp_get_num_threads' returns 1. 483 484 The default team size may be initialized at startup by the 485 'OMP_NUM_THREADS' environment variable. At runtime, the size of 486 the current team may be set either by the 'NUM_THREADS' clause or 487 by 'omp_set_num_threads'. If none of the above were used to define 488 a specific value and 'OMP_DYNAMIC' is disabled, one thread per CPU 489 online is used. 490 491 _C/C++_: 492 _Prototype_: 'int omp_get_num_threads(void);' 493 494 _Fortran_: 495 _Interface_: 'integer function omp_get_num_threads()' 496 497 _See also_: 498 *note omp_get_max_threads::, *note omp_set_num_threads::, *note 499 OMP_NUM_THREADS:: 500 501 _Reference_: 502 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.2. 503 504 505 File: libgomp.info, Node: omp_get_proc_bind, Next: omp_get_schedule, Prev: omp_get_num_threads, Up: Runtime Library Routines 506 507 2.15 'omp_get_proc_bind' - Whether theads may be moved between CPUs 508 =================================================================== 509 510 _Description_: 511 This functions returns the currently active thread affinity policy, 512 which is set via 'OMP_PROC_BIND'. Possible values are 513 'omp_proc_bind_false', 'omp_proc_bind_true', 514 'omp_proc_bind_master', 'omp_proc_bind_close' and 515 'omp_proc_bind_spread'. 516 517 _C/C++_: 518 _Prototype_: 'omp_proc_bind_t omp_get_proc_bind(void);' 519 520 _Fortran_: 521 _Interface_: 'integer(kind=omp_proc_bind_kind) function 522 omp_get_proc_bind()' 523 524 _See also_: 525 *note OMP_PROC_BIND::, *note OMP_PLACES::, *note 526 GOMP_CPU_AFFINITY::, 527 528 _Reference_: 529 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.22. 530 531 532 File: libgomp.info, Node: omp_get_schedule, Next: omp_get_team_num, Prev: omp_get_proc_bind, Up: Runtime Library Routines 533 534 2.16 'omp_get_schedule' - Obtain the runtime scheduling method 535 ============================================================== 536 537 _Description_: 538 Obtain the runtime scheduling method. The KIND argument will be 539 set to the value 'omp_sched_static', 'omp_sched_dynamic', 540 'omp_sched_guided' or 'omp_sched_auto'. The second argument, 541 CHUNK_SIZE, is set to the chunk size. 542 543 _C/C++_ 544 _Prototype_: 'void omp_get_schedule(omp_sched_t *kind, int 545 *chunk_size);' 546 547 _Fortran_: 548 _Interface_: 'subroutine omp_get_schedule(kind, chunk_size)' 549 'integer(kind=omp_sched_kind) kind' 550 'integer chunk_size' 551 552 _See also_: 553 *note omp_set_schedule::, *note OMP_SCHEDULE:: 554 555 _Reference_: 556 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.13. 557 558 559 File: libgomp.info, Node: omp_get_team_num, Next: omp_get_team_size, Prev: omp_get_schedule, Up: Runtime Library Routines 560 561 2.17 'omp_get_team_num' - Get team number 562 ========================================= 563 564 _Description_: 565 Returns the team number of the calling thread. 566 567 _C/C++_: 568 _Prototype_: 'int omp_get_team_num(void);' 569 570 _Fortran_: 571 _Interface_: 'integer function omp_get_team_num()' 572 573 _Reference_: 574 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.33. 575 576 577 File: libgomp.info, Node: omp_get_team_size, Next: omp_get_thread_limit, Prev: omp_get_team_num, Up: Runtime Library Routines 578 579 2.18 'omp_get_team_size' - Number of threads in a team 580 ====================================================== 581 582 _Description_: 583 This function returns the number of threads in a thread team to 584 which either the current thread or its ancestor belongs. For 585 values of LEVEL outside zero to 'omp_get_level', -1 is returned; if 586 LEVEL is zero, 1 is returned, and for 'omp_get_level', the result 587 is identical to 'omp_get_num_threads'. 588 589 _C/C++_: 590 _Prototype_: 'int omp_get_team_size(int level);' 591 592 _Fortran_: 593 _Interface_: 'integer function omp_get_team_size(level)' 594 'integer level' 595 596 _See also_: 597 *note omp_get_num_threads::, *note omp_get_level::, *note 598 omp_get_ancestor_thread_num:: 599 600 _Reference_: 601 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.19. 602 603 604 File: libgomp.info, Node: omp_get_thread_limit, Next: omp_get_thread_num, Prev: omp_get_team_size, Up: Runtime Library Routines 605 606 2.19 'omp_get_thread_limit' - Maximum number of threads 607 ======================================================= 608 609 _Description_: 610 Return the maximum number of threads of the program. 611 612 _C/C++_: 613 _Prototype_: 'int omp_get_thread_limit(void);' 614 615 _Fortran_: 616 _Interface_: 'integer function omp_get_thread_limit()' 617 618 _See also_: 619 *note omp_get_max_threads::, *note OMP_THREAD_LIMIT:: 620 621 _Reference_: 622 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.14. 623 624 625 File: libgomp.info, Node: omp_get_thread_num, Next: omp_in_parallel, Prev: omp_get_thread_limit, Up: Runtime Library Routines 626 627 2.20 'omp_get_thread_num' - Current thread ID 628 ============================================= 629 630 _Description_: 631 Returns a unique thread identification number within the current 632 team. In a sequential parts of the program, 'omp_get_thread_num' 633 always returns 0. In parallel regions the return value varies from 634 0 to 'omp_get_num_threads'-1 inclusive. The return value of the 635 master thread of a team is always 0. 636 637 _C/C++_: 638 _Prototype_: 'int omp_get_thread_num(void);' 639 640 _Fortran_: 641 _Interface_: 'integer function omp_get_thread_num()' 642 643 _See also_: 644 *note omp_get_num_threads::, *note omp_get_ancestor_thread_num:: 645 646 _Reference_: 647 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.4. 648 649 650 File: libgomp.info, Node: omp_in_parallel, Next: omp_in_final, Prev: omp_get_thread_num, Up: Runtime Library Routines 651 652 2.21 'omp_in_parallel' - Whether a parallel region is active 653 ============================================================ 654 655 _Description_: 656 This function returns 'true' if currently running in parallel, 657 'false' otherwise. Here, 'true' and 'false' represent their 658 language-specific counterparts. 659 660 _C/C++_: 661 _Prototype_: 'int omp_in_parallel(void);' 662 663 _Fortran_: 664 _Interface_: 'logical function omp_in_parallel()' 665 666 _Reference_: 667 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.6. 668 669 670 File: libgomp.info, Node: omp_in_final, Next: omp_is_initial_device, Prev: omp_in_parallel, Up: Runtime Library Routines 671 672 2.22 'omp_in_final' - Whether in final or included task region 673 ============================================================== 674 675 _Description_: 676 This function returns 'true' if currently running in a final or 677 included task region, 'false' otherwise. Here, 'true' and 'false' 678 represent their language-specific counterparts. 679 680 _C/C++_: 681 _Prototype_: 'int omp_in_final(void);' 682 683 _Fortran_: 684 _Interface_: 'logical function omp_in_final()' 685 686 _Reference_: 687 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.21. 688 689 690 File: libgomp.info, Node: omp_is_initial_device, Next: omp_set_default_device, Prev: omp_in_final, Up: Runtime Library Routines 691 692 2.23 'omp_is_initial_device' - Whether executing on the host device 693 =================================================================== 694 695 _Description_: 696 This function returns 'true' if currently running on the host 697 device, 'false' otherwise. Here, 'true' and 'false' represent 698 their language-specific counterparts. 699 700 _C/C++_: 701 _Prototype_: 'int omp_is_initial_device(void);' 702 703 _Fortran_: 704 _Interface_: 'logical function omp_is_initial_device()' 705 706 _Reference_: 707 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.34. 708 709 710 File: libgomp.info, Node: omp_set_default_device, Next: omp_set_dynamic, Prev: omp_is_initial_device, Up: Runtime Library Routines 711 712 2.24 'omp_set_default_device' - Set the default device for target regions 713 ========================================================================= 714 715 _Description_: 716 Set the default device for target regions without device clause. 717 The argument shall be a nonnegative device number. 718 719 _C/C++_: 720 _Prototype_: 'void omp_set_default_device(int device_num);' 721 722 _Fortran_: 723 _Interface_: 'subroutine omp_set_default_device(device_num)' 724 'integer device_num' 725 726 _See also_: 727 *note OMP_DEFAULT_DEVICE::, *note omp_get_default_device:: 728 729 _Reference_: 730 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.29. 731 732 733 File: libgomp.info, Node: omp_set_dynamic, Next: omp_set_max_active_levels, Prev: omp_set_default_device, Up: Runtime Library Routines 734 735 2.25 'omp_set_dynamic' - Enable/disable dynamic teams 736 ===================================================== 737 738 _Description_: 739 Enable or disable the dynamic adjustment of the number of threads 740 within a team. The function takes the language-specific equivalent 741 of 'true' and 'false', where 'true' enables dynamic adjustment of 742 team sizes and 'false' disables it. 743 744 _C/C++_: 745 _Prototype_: 'void omp_set_dynamic(int dynamic_threads);' 746 747 _Fortran_: 748 _Interface_: 'subroutine omp_set_dynamic(dynamic_threads)' 749 'logical, intent(in) :: dynamic_threads' 750 751 _See also_: 752 *note OMP_DYNAMIC::, *note omp_get_dynamic:: 753 754 _Reference_: 755 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.7. 756 757 758 File: libgomp.info, Node: omp_set_max_active_levels, Next: omp_set_nested, Prev: omp_set_dynamic, Up: Runtime Library Routines 759 760 2.26 'omp_set_max_active_levels' - Limits the number of active parallel regions 761 =============================================================================== 762 763 _Description_: 764 This function limits the maximum allowed number of nested, active 765 parallel regions. 766 767 _C/C++_ 768 _Prototype_: 'void omp_set_max_active_levels(int max_levels);' 769 770 _Fortran_: 771 _Interface_: 'subroutine omp_set_max_active_levels(max_levels)' 772 'integer max_levels' 773 774 _See also_: 775 *note omp_get_max_active_levels::, *note omp_get_active_level:: 776 777 _Reference_: 778 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.15. 779 780 781 File: libgomp.info, Node: omp_set_nested, Next: omp_set_num_threads, Prev: omp_set_max_active_levels, Up: Runtime Library Routines 782 783 2.27 'omp_set_nested' - Enable/disable nested parallel regions 784 ============================================================== 785 786 _Description_: 787 Enable or disable nested parallel regions, i.e., whether team 788 members are allowed to create new teams. The function takes the 789 language-specific equivalent of 'true' and 'false', where 'true' 790 enables dynamic adjustment of team sizes and 'false' disables it. 791 792 _C/C++_: 793 _Prototype_: 'void omp_set_nested(int nested);' 794 795 _Fortran_: 796 _Interface_: 'subroutine omp_set_nested(nested)' 797 'logical, intent(in) :: nested' 798 799 _See also_: 800 *note OMP_NESTED::, *note omp_get_nested:: 801 802 _Reference_: 803 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.10. 804 805 806 File: libgomp.info, Node: omp_set_num_threads, Next: omp_set_schedule, Prev: omp_set_nested, Up: Runtime Library Routines 807 808 2.28 'omp_set_num_threads' - Set upper team size limit 809 ====================================================== 810 811 _Description_: 812 Specifies the number of threads used by default in subsequent 813 parallel sections, if those do not specify a 'num_threads' clause. 814 The argument of 'omp_set_num_threads' shall be a positive integer. 815 816 _C/C++_: 817 _Prototype_: 'void omp_set_num_threads(int num_threads);' 818 819 _Fortran_: 820 _Interface_: 'subroutine omp_set_num_threads(num_threads)' 821 'integer, intent(in) :: num_threads' 822 823 _See also_: 824 *note OMP_NUM_THREADS::, *note omp_get_num_threads::, *note 825 omp_get_max_threads:: 826 827 _Reference_: 828 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.1. 829 830 831 File: libgomp.info, Node: omp_set_schedule, Next: omp_init_lock, Prev: omp_set_num_threads, Up: Runtime Library Routines 832 833 2.29 'omp_set_schedule' - Set the runtime scheduling method 834 =========================================================== 835 836 _Description_: 837 Sets the runtime scheduling method. The KIND argument can have the 838 value 'omp_sched_static', 'omp_sched_dynamic', 'omp_sched_guided' 839 or 'omp_sched_auto'. Except for 'omp_sched_auto', the chunk size 840 is set to the value of CHUNK_SIZE if positive, or to the default 841 value if zero or negative. For 'omp_sched_auto' the CHUNK_SIZE 842 argument is ignored. 843 844 _C/C++_ 845 _Prototype_: 'void omp_set_schedule(omp_sched_t kind, int 846 chunk_size);' 847 848 _Fortran_: 849 _Interface_: 'subroutine omp_set_schedule(kind, chunk_size)' 850 'integer(kind=omp_sched_kind) kind' 851 'integer chunk_size' 852 853 _See also_: 854 *note omp_get_schedule:: *note OMP_SCHEDULE:: 855 856 _Reference_: 857 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.2.12. 858 859 860 File: libgomp.info, Node: omp_init_lock, Next: omp_set_lock, Prev: omp_set_schedule, Up: Runtime Library Routines 861 862 2.30 'omp_init_lock' - Initialize simple lock 863 ============================================= 864 865 _Description_: 866 Initialize a simple lock. After initialization, the lock is in an 867 unlocked state. 868 869 _C/C++_: 870 _Prototype_: 'void omp_init_lock(omp_lock_t *lock);' 871 872 _Fortran_: 873 _Interface_: 'subroutine omp_init_lock(svar)' 874 'integer(omp_lock_kind), intent(out) :: svar' 875 876 _See also_: 877 *note omp_destroy_lock:: 878 879 _Reference_: 880 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.1. 881 882 883 File: libgomp.info, Node: omp_set_lock, Next: omp_test_lock, Prev: omp_init_lock, Up: Runtime Library Routines 884 885 2.31 'omp_set_lock' - Wait for and set simple lock 886 ================================================== 887 888 _Description_: 889 Before setting a simple lock, the lock variable must be initialized 890 by 'omp_init_lock'. The calling thread is blocked until the lock 891 is available. If the lock is already held by the current thread, a 892 deadlock occurs. 893 894 _C/C++_: 895 _Prototype_: 'void omp_set_lock(omp_lock_t *lock);' 896 897 _Fortran_: 898 _Interface_: 'subroutine omp_set_lock(svar)' 899 'integer(omp_lock_kind), intent(inout) :: svar' 900 901 _See also_: 902 *note omp_init_lock::, *note omp_test_lock::, *note 903 omp_unset_lock:: 904 905 _Reference_: 906 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.4. 907 908 909 File: libgomp.info, Node: omp_test_lock, Next: omp_unset_lock, Prev: omp_set_lock, Up: Runtime Library Routines 910 911 2.32 'omp_test_lock' - Test and set simple lock if available 912 ============================================================ 913 914 _Description_: 915 Before setting a simple lock, the lock variable must be initialized 916 by 'omp_init_lock'. Contrary to 'omp_set_lock', 'omp_test_lock' 917 does not block if the lock is not available. This function returns 918 'true' upon success, 'false' otherwise. Here, 'true' and 'false' 919 represent their language-specific counterparts. 920 921 _C/C++_: 922 _Prototype_: 'int omp_test_lock(omp_lock_t *lock);' 923 924 _Fortran_: 925 _Interface_: 'logical function omp_test_lock(svar)' 926 'integer(omp_lock_kind), intent(inout) :: svar' 927 928 _See also_: 929 *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock:: 930 931 _Reference_: 932 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.6. 933 934 935 File: libgomp.info, Node: omp_unset_lock, Next: omp_destroy_lock, Prev: omp_test_lock, Up: Runtime Library Routines 936 937 2.33 'omp_unset_lock' - Unset simple lock 938 ========================================= 939 940 _Description_: 941 A simple lock about to be unset must have been locked by 942 'omp_set_lock' or 'omp_test_lock' before. In addition, the lock 943 must be held by the thread calling 'omp_unset_lock'. Then, the 944 lock becomes unlocked. If one or more threads attempted to set the 945 lock before, one of them is chosen to, again, set the lock to 946 itself. 947 948 _C/C++_: 949 _Prototype_: 'void omp_unset_lock(omp_lock_t *lock);' 950 951 _Fortran_: 952 _Interface_: 'subroutine omp_unset_lock(svar)' 953 'integer(omp_lock_kind), intent(inout) :: svar' 954 955 _See also_: 956 *note omp_set_lock::, *note omp_test_lock:: 957 958 _Reference_: 959 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.5. 960 961 962 File: libgomp.info, Node: omp_destroy_lock, Next: omp_init_nest_lock, Prev: omp_unset_lock, Up: Runtime Library Routines 963 964 2.34 'omp_destroy_lock' - Destroy simple lock 965 ============================================= 966 967 _Description_: 968 Destroy a simple lock. In order to be destroyed, a simple lock 969 must be in the unlocked state. 970 971 _C/C++_: 972 _Prototype_: 'void omp_destroy_lock(omp_lock_t *lock);' 973 974 _Fortran_: 975 _Interface_: 'subroutine omp_destroy_lock(svar)' 976 'integer(omp_lock_kind), intent(inout) :: svar' 977 978 _See also_: 979 *note omp_init_lock:: 980 981 _Reference_: 982 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.3. 983 984 985 File: libgomp.info, Node: omp_init_nest_lock, Next: omp_set_nest_lock, Prev: omp_destroy_lock, Up: Runtime Library Routines 986 987 2.35 'omp_init_nest_lock' - Initialize nested lock 988 ================================================== 989 990 _Description_: 991 Initialize a nested lock. After initialization, the lock is in an 992 unlocked state and the nesting count is set to zero. 993 994 _C/C++_: 995 _Prototype_: 'void omp_init_nest_lock(omp_nest_lock_t *lock);' 996 997 _Fortran_: 998 _Interface_: 'subroutine omp_init_nest_lock(nvar)' 999 'integer(omp_nest_lock_kind), intent(out) :: nvar' 1000 1001 _See also_: 1002 *note omp_destroy_nest_lock:: 1003 1004 _Reference_: 1005 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.1. 1006 1007 1008 File: libgomp.info, Node: omp_set_nest_lock, Next: omp_test_nest_lock, Prev: omp_init_nest_lock, Up: Runtime Library Routines 1009 1010 2.36 'omp_set_nest_lock' - Wait for and set nested lock 1011 ======================================================= 1012 1013 _Description_: 1014 Before setting a nested lock, the lock variable must be initialized 1015 by 'omp_init_nest_lock'. The calling thread is blocked until the 1016 lock is available. If the lock is already held by the current 1017 thread, the nesting count for the lock is incremented. 1018 1019 _C/C++_: 1020 _Prototype_: 'void omp_set_nest_lock(omp_nest_lock_t *lock);' 1021 1022 _Fortran_: 1023 _Interface_: 'subroutine omp_set_nest_lock(nvar)' 1024 'integer(omp_nest_lock_kind), intent(inout) :: nvar' 1025 1026 _See also_: 1027 *note omp_init_nest_lock::, *note omp_unset_nest_lock:: 1028 1029 _Reference_: 1030 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.4. 1031 1032 1033 File: libgomp.info, Node: omp_test_nest_lock, Next: omp_unset_nest_lock, Prev: omp_set_nest_lock, Up: Runtime Library Routines 1034 1035 2.37 'omp_test_nest_lock' - Test and set nested lock if available 1036 ================================================================= 1037 1038 _Description_: 1039 Before setting a nested lock, the lock variable must be initialized 1040 by 'omp_init_nest_lock'. Contrary to 'omp_set_nest_lock', 1041 'omp_test_nest_lock' does not block if the lock is not available. 1042 If the lock is already held by the current thread, the new nesting 1043 count is returned. Otherwise, the return value equals zero. 1044 1045 _C/C++_: 1046 _Prototype_: 'int omp_test_nest_lock(omp_nest_lock_t *lock);' 1047 1048 _Fortran_: 1049 _Interface_: 'logical function omp_test_nest_lock(nvar)' 1050 'integer(omp_nest_lock_kind), intent(inout) :: nvar' 1051 1052 _See also_: 1053 *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock:: 1054 1055 _Reference_: 1056 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.6. 1057 1058 1059 File: libgomp.info, Node: omp_unset_nest_lock, Next: omp_destroy_nest_lock, Prev: omp_test_nest_lock, Up: Runtime Library Routines 1060 1061 2.38 'omp_unset_nest_lock' - Unset nested lock 1062 ============================================== 1063 1064 _Description_: 1065 A nested lock about to be unset must have been locked by 1066 'omp_set_nested_lock' or 'omp_test_nested_lock' before. In 1067 addition, the lock must be held by the thread calling 1068 'omp_unset_nested_lock'. If the nesting count drops to zero, the 1069 lock becomes unlocked. If one ore more threads attempted to set 1070 the lock before, one of them is chosen to, again, set the lock to 1071 itself. 1072 1073 _C/C++_: 1074 _Prototype_: 'void omp_unset_nest_lock(omp_nest_lock_t *lock);' 1075 1076 _Fortran_: 1077 _Interface_: 'subroutine omp_unset_nest_lock(nvar)' 1078 'integer(omp_nest_lock_kind), intent(inout) :: nvar' 1079 1080 _See also_: 1081 *note omp_set_nest_lock:: 1082 1083 _Reference_: 1084 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.5. 1085 1086 1087 File: libgomp.info, Node: omp_destroy_nest_lock, Next: omp_get_wtick, Prev: omp_unset_nest_lock, Up: Runtime Library Routines 1088 1089 2.39 'omp_destroy_nest_lock' - Destroy nested lock 1090 ================================================== 1091 1092 _Description_: 1093 Destroy a nested lock. In order to be destroyed, a nested lock 1094 must be in the unlocked state and its nesting count must equal 1095 zero. 1096 1097 _C/C++_: 1098 _Prototype_: 'void omp_destroy_nest_lock(omp_nest_lock_t *);' 1099 1100 _Fortran_: 1101 _Interface_: 'subroutine omp_destroy_nest_lock(nvar)' 1102 'integer(omp_nest_lock_kind), intent(inout) :: nvar' 1103 1104 _See also_: 1105 *note omp_init_lock:: 1106 1107 _Reference_: 1108 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.3.3. 1109 1110 1111 File: libgomp.info, Node: omp_get_wtick, Next: omp_get_wtime, Prev: omp_destroy_nest_lock, Up: Runtime Library Routines 1112 1113 2.40 'omp_get_wtick' - Get timer precision 1114 ========================================== 1115 1116 _Description_: 1117 Gets the timer precision, i.e., the number of seconds between two 1118 successive clock ticks. 1119 1120 _C/C++_: 1121 _Prototype_: 'double omp_get_wtick(void);' 1122 1123 _Fortran_: 1124 _Interface_: 'double precision function omp_get_wtick()' 1125 1126 _See also_: 1127 *note omp_get_wtime:: 1128 1129 _Reference_: 1130 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.4.2. 1131 1132 1133 File: libgomp.info, Node: omp_get_wtime, Prev: omp_get_wtick, Up: Runtime Library Routines 1134 1135 2.41 'omp_get_wtime' - Elapsed wall clock time 1136 ============================================== 1137 1138 _Description_: 1139 Elapsed wall clock time in seconds. The time is measured per 1140 thread, no guarantee can be made that two distinct threads measure 1141 the same time. Time is measured from some "time in the past", 1142 which is an arbitrary time guaranteed not to change during the 1143 execution of the program. 1144 1145 _C/C++_: 1146 _Prototype_: 'double omp_get_wtime(void);' 1147 1148 _Fortran_: 1149 _Interface_: 'double precision function omp_get_wtime()' 1150 1151 _See also_: 1152 *note omp_get_wtick:: 1153 1154 _Reference_: 1155 OpenMP specification v4.5 (http://www.openmp.org/), Section 3.4.1. 1156 1157 1158 File: libgomp.info, Node: Environment Variables, Next: Enabling OpenACC, Prev: Runtime Library Routines, Up: Top 1159 1160 3 Environment Variables 1161 *********************** 1162 1163 The environment variables which beginning with 'OMP_' are defined by 1164 section 4 of the OpenMP specification in version 4.5, while those 1165 beginning with 'GOMP_' are GNU extensions. 1166 1167 * Menu: 1168 1169 * OMP_CANCELLATION:: Set whether cancellation is activated 1170 * OMP_DISPLAY_ENV:: Show OpenMP version and environment variables 1171 * OMP_DEFAULT_DEVICE:: Set the device used in target regions 1172 * OMP_DYNAMIC:: Dynamic adjustment of threads 1173 * OMP_MAX_ACTIVE_LEVELS:: Set the maximum number of nested parallel regions 1174 * OMP_MAX_TASK_PRIORITY:: Set the maximum task priority value 1175 * OMP_NESTED:: Nested parallel regions 1176 * OMP_NUM_THREADS:: Specifies the number of threads to use 1177 * OMP_PROC_BIND:: Whether theads may be moved between CPUs 1178 * OMP_PLACES:: Specifies on which CPUs the theads should be placed 1179 * OMP_STACKSIZE:: Set default thread stack size 1180 * OMP_SCHEDULE:: How threads are scheduled 1181 * OMP_THREAD_LIMIT:: Set the maximum number of threads 1182 * OMP_WAIT_POLICY:: How waiting threads are handled 1183 * GOMP_CPU_AFFINITY:: Bind threads to specific CPUs 1184 * GOMP_DEBUG:: Enable debugging output 1185 * GOMP_STACKSIZE:: Set default thread stack size 1186 * GOMP_SPINCOUNT:: Set the busy-wait spin count 1187 * GOMP_RTEMS_THREAD_POOLS:: Set the RTEMS specific thread pools 1188 1189 1190 File: libgomp.info, Node: OMP_CANCELLATION, Next: OMP_DISPLAY_ENV, Up: Environment Variables 1191 1192 3.1 'OMP_CANCELLATION' - Set whether cancellation is activated 1193 ============================================================== 1194 1195 _Description_: 1196 If set to 'TRUE', the cancellation is activated. If set to 'FALSE' 1197 or if unset, cancellation is disabled and the 'cancel' construct is 1198 ignored. 1199 1200 _See also_: 1201 *note omp_get_cancellation:: 1202 1203 _Reference_: 1204 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.11 1205 1206 1207 File: libgomp.info, Node: OMP_DISPLAY_ENV, Next: OMP_DEFAULT_DEVICE, Prev: OMP_CANCELLATION, Up: Environment Variables 1208 1209 3.2 'OMP_DISPLAY_ENV' - Show OpenMP version and environment variables 1210 ===================================================================== 1211 1212 _Description_: 1213 If set to 'TRUE', the OpenMP version number and the values 1214 associated with the OpenMP environment variables are printed to 1215 'stderr'. If set to 'VERBOSE', it additionally shows the value of 1216 the environment variables which are GNU extensions. If undefined 1217 or set to 'FALSE', this information will not be shown. 1218 1219 _Reference_: 1220 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.12 1221 1222 1223 File: libgomp.info, Node: OMP_DEFAULT_DEVICE, Next: OMP_DYNAMIC, Prev: OMP_DISPLAY_ENV, Up: Environment Variables 1224 1225 3.3 'OMP_DEFAULT_DEVICE' - Set the device used in target regions 1226 ================================================================ 1227 1228 _Description_: 1229 Set to choose the device which is used in a 'target' region, unless 1230 the value is overridden by 'omp_set_default_device' or by a 1231 'device' clause. The value shall be the nonnegative device number. 1232 If no device with the given device number exists, the code is 1233 executed on the host. If unset, device number 0 will be used. 1234 1235 _See also_: 1236 *note omp_get_default_device::, *note omp_set_default_device::, 1237 1238 _Reference_: 1239 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.13 1240 1241 1242 File: libgomp.info, Node: OMP_DYNAMIC, Next: OMP_MAX_ACTIVE_LEVELS, Prev: OMP_DEFAULT_DEVICE, Up: Environment Variables 1243 1244 3.4 'OMP_DYNAMIC' - Dynamic adjustment of threads 1245 ================================================= 1246 1247 _Description_: 1248 Enable or disable the dynamic adjustment of the number of threads 1249 within a team. The value of this environment variable shall be 1250 'TRUE' or 'FALSE'. If undefined, dynamic adjustment is disabled by 1251 default. 1252 1253 _See also_: 1254 *note omp_set_dynamic:: 1255 1256 _Reference_: 1257 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.3 1258 1259 1260 File: libgomp.info, Node: OMP_MAX_ACTIVE_LEVELS, Next: OMP_MAX_TASK_PRIORITY, Prev: OMP_DYNAMIC, Up: Environment Variables 1261 1262 3.5 'OMP_MAX_ACTIVE_LEVELS' - Set the maximum number of nested parallel regions 1263 =============================================================================== 1264 1265 _Description_: 1266 Specifies the initial value for the maximum number of nested 1267 parallel regions. The value of this variable shall be a positive 1268 integer. If undefined, the number of active levels is unlimited. 1269 1270 _See also_: 1271 *note omp_set_max_active_levels:: 1272 1273 _Reference_: 1274 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.9 1275 1276 1277 File: libgomp.info, Node: OMP_MAX_TASK_PRIORITY, Next: OMP_NESTED, Prev: OMP_MAX_ACTIVE_LEVELS, Up: Environment Variables 1278 1279 3.6 'OMP_MAX_TASK_PRIORITY' - Set the maximum priority 1280 ====================================================== 1281 1282 number that can be set for a task. 1283 _Description_: 1284 Specifies the initial value for the maximum priority value that can 1285 be set for a task. The value of this variable shall be a 1286 non-negative integer, and zero is allowed. If undefined, the 1287 default priority is 0. 1288 1289 _See also_: 1290 *note omp_get_max_task_priority:: 1291 1292 _Reference_: 1293 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.14 1294 1295 1296 File: libgomp.info, Node: OMP_NESTED, Next: OMP_NUM_THREADS, Prev: OMP_MAX_TASK_PRIORITY, Up: Environment Variables 1297 1298 3.7 'OMP_NESTED' - Nested parallel regions 1299 ========================================== 1300 1301 _Description_: 1302 Enable or disable nested parallel regions, i.e., whether team 1303 members are allowed to create new teams. The value of this 1304 environment variable shall be 'TRUE' or 'FALSE'. If undefined, 1305 nested parallel regions are disabled by default. 1306 1307 _See also_: 1308 *note omp_set_nested:: 1309 1310 _Reference_: 1311 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.6 1312 1313 1314 File: libgomp.info, Node: OMP_NUM_THREADS, Next: OMP_PROC_BIND, Prev: OMP_NESTED, Up: Environment Variables 1315 1316 3.8 'OMP_NUM_THREADS' - Specifies the number of threads to use 1317 ============================================================== 1318 1319 _Description_: 1320 Specifies the default number of threads to use in parallel regions. 1321 The value of this variable shall be a comma-separated list of 1322 positive integers; the value specified the number of threads to use 1323 for the corresponding nested level. If undefined one thread per 1324 CPU is used. 1325 1326 _See also_: 1327 *note omp_set_num_threads:: 1328 1329 _Reference_: 1330 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.2 1331 1332 1333 File: libgomp.info, Node: OMP_PROC_BIND, Next: OMP_PLACES, Prev: OMP_NUM_THREADS, Up: Environment Variables 1334 1335 3.9 'OMP_PROC_BIND' - Whether theads may be moved between CPUs 1336 ============================================================== 1337 1338 _Description_: 1339 Specifies whether threads may be moved between processors. If set 1340 to 'TRUE', OpenMP theads should not be moved; if set to 'FALSE' 1341 they may be moved. Alternatively, a comma separated list with the 1342 values 'MASTER', 'CLOSE' and 'SPREAD' can be used to specify the 1343 thread affinity policy for the corresponding nesting level. With 1344 'MASTER' the worker threads are in the same place partition as the 1345 master thread. With 'CLOSE' those are kept close to the master 1346 thread in contiguous place partitions. And with 'SPREAD' a sparse 1347 distribution across the place partitions is used. 1348 1349 When undefined, 'OMP_PROC_BIND' defaults to 'TRUE' when 1350 'OMP_PLACES' or 'GOMP_CPU_AFFINITY' is set and 'FALSE' otherwise. 1351 1352 _See also_: 1353 *note OMP_PLACES::, *note GOMP_CPU_AFFINITY::, *note 1354 omp_get_proc_bind:: 1355 1356 _Reference_: 1357 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.4 1358 1359 1360 File: libgomp.info, Node: OMP_PLACES, Next: OMP_STACKSIZE, Prev: OMP_PROC_BIND, Up: Environment Variables 1361 1362 3.10 'OMP_PLACES' - Specifies on which CPUs the theads should be placed 1363 ======================================================================= 1364 1365 _Description_: 1366 The thread placement can be either specified using an abstract name 1367 or by an explicit list of the places. The abstract names 1368 'threads', 'cores' and 'sockets' can be optionally followed by a 1369 positive number in parentheses, which denotes the how many places 1370 shall be created. With 'threads' each place corresponds to a 1371 single hardware thread; 'cores' to a single core with the 1372 corresponding number of hardware threads; and with 'sockets' the 1373 place corresponds to a single socket. The resulting placement can 1374 be shown by setting the 'OMP_DISPLAY_ENV' environment variable. 1375 1376 Alternatively, the placement can be specified explicitly as 1377 comma-separated list of places. A place is specified by set of 1378 nonnegative numbers in curly braces, denoting the denoting the 1379 hardware threads. The hardware threads belonging to a place can 1380 either be specified as comma-separated list of nonnegative thread 1381 numbers or using an interval. Multiple places can also be either 1382 specified by a comma-separated list of places or by an interval. 1383 To specify an interval, a colon followed by the count is placed 1384 after after the hardware thread number or the place. Optionally, 1385 the length can be followed by a colon and the stride number - 1386 otherwise a unit stride is assumed. For instance, the following 1387 specifies the same places list: '"{0,1,2}, {3,4,6}, {7,8,9}, 1388 {10,11,12}"'; '"{0:3}, {3:3}, {7:3}, {10:3}"'; and '"{0:2}:4:3"'. 1389 1390 If 'OMP_PLACES' and 'GOMP_CPU_AFFINITY' are unset and 1391 'OMP_PROC_BIND' is either unset or 'false', threads may be moved 1392 between CPUs following no placement policy. 1393 1394 _See also_: 1395 *note OMP_PROC_BIND::, *note GOMP_CPU_AFFINITY::, *note 1396 omp_get_proc_bind::, *note OMP_DISPLAY_ENV:: 1397 1398 _Reference_: 1399 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.5 1400 1401 1402 File: libgomp.info, Node: OMP_STACKSIZE, Next: OMP_SCHEDULE, Prev: OMP_PLACES, Up: Environment Variables 1403 1404 3.11 'OMP_STACKSIZE' - Set default thread stack size 1405 ==================================================== 1406 1407 _Description_: 1408 Set the default thread stack size in kilobytes, unless the number 1409 is suffixed by 'B', 'K', 'M' or 'G', in which case the size is, 1410 respectively, in bytes, kilobytes, megabytes or gigabytes. This is 1411 different from 'pthread_attr_setstacksize' which gets the number of 1412 bytes as an argument. If the stack size cannot be set due to 1413 system constraints, an error is reported and the initial stack size 1414 is left unchanged. If undefined, the stack size is system 1415 dependent. 1416 1417 _Reference_: 1418 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.7 1419 1420 1421 File: libgomp.info, Node: OMP_SCHEDULE, Next: OMP_THREAD_LIMIT, Prev: OMP_STACKSIZE, Up: Environment Variables 1422 1423 3.12 'OMP_SCHEDULE' - How threads are scheduled 1424 =============================================== 1425 1426 _Description_: 1427 Allows to specify 'schedule type' and 'chunk size'. The value of 1428 the variable shall have the form: 'type[,chunk]' where 'type' is 1429 one of 'static', 'dynamic', 'guided' or 'auto' The optional 'chunk' 1430 size shall be a positive integer. If undefined, dynamic scheduling 1431 and a chunk size of 1 is used. 1432 1433 _See also_: 1434 *note omp_set_schedule:: 1435 1436 _Reference_: 1437 OpenMP specification v4.5 (http://www.openmp.org/), Sections 1438 2.7.1.1 and 4.1 1439 1440 1441 File: libgomp.info, Node: OMP_THREAD_LIMIT, Next: OMP_WAIT_POLICY, Prev: OMP_SCHEDULE, Up: Environment Variables 1442 1443 3.13 'OMP_THREAD_LIMIT' - Set the maximum number of threads 1444 =========================================================== 1445 1446 _Description_: 1447 Specifies the number of threads to use for the whole program. The 1448 value of this variable shall be a positive integer. If undefined, 1449 the number of threads is not limited. 1450 1451 _See also_: 1452 *note OMP_NUM_THREADS::, *note omp_get_thread_limit:: 1453 1454 _Reference_: 1455 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.10 1456 1457 1458 File: libgomp.info, Node: OMP_WAIT_POLICY, Next: GOMP_CPU_AFFINITY, Prev: OMP_THREAD_LIMIT, Up: Environment Variables 1459 1460 3.14 'OMP_WAIT_POLICY' - How waiting threads are handled 1461 ======================================================== 1462 1463 _Description_: 1464 Specifies whether waiting threads should be active or passive. If 1465 the value is 'PASSIVE', waiting threads should not consume CPU 1466 power while waiting; while the value is 'ACTIVE' specifies that 1467 they should. If undefined, threads wait actively for a short time 1468 before waiting passively. 1469 1470 _See also_: 1471 *note GOMP_SPINCOUNT:: 1472 1473 _Reference_: 1474 OpenMP specification v4.5 (http://www.openmp.org/), Section 4.8 1475 1476 1477 File: libgomp.info, Node: GOMP_CPU_AFFINITY, Next: GOMP_DEBUG, Prev: OMP_WAIT_POLICY, Up: Environment Variables 1478 1479 3.15 'GOMP_CPU_AFFINITY' - Bind threads to specific CPUs 1480 ======================================================== 1481 1482 _Description_: 1483 Binds threads to specific CPUs. The variable should contain a 1484 space-separated or comma-separated list of CPUs. This list may 1485 contain different kinds of entries: either single CPU numbers in 1486 any order, a range of CPUs (M-N) or a range with some stride 1487 (M-N:S). CPU numbers are zero based. For example, 1488 'GOMP_CPU_AFFINITY="0 3 1-2 4-15:2"' will bind the initial thread 1489 to CPU 0, the second to CPU 3, the third to CPU 1, the fourth to 1490 CPU 2, the fifth to CPU 4, the sixth through tenth to CPUs 6, 8, 1491 10, 12, and 14 respectively and then start assigning back from the 1492 beginning of the list. 'GOMP_CPU_AFFINITY=0' binds all threads to 1493 CPU 0. 1494 1495 There is no libgomp library routine to determine whether a CPU 1496 affinity specification is in effect. As a workaround, 1497 language-specific library functions, e.g., 'getenv' in C or 1498 'GET_ENVIRONMENT_VARIABLE' in Fortran, may be used to query the 1499 setting of the 'GOMP_CPU_AFFINITY' environment variable. A defined 1500 CPU affinity on startup cannot be changed or disabled during the 1501 runtime of the application. 1502 1503 If both 'GOMP_CPU_AFFINITY' and 'OMP_PROC_BIND' are set, 1504 'OMP_PROC_BIND' has a higher precedence. If neither has been set 1505 and 'OMP_PROC_BIND' is unset, or when 'OMP_PROC_BIND' is set to 1506 'FALSE', the host system will handle the assignment of threads to 1507 CPUs. 1508 1509 _See also_: 1510 *note OMP_PLACES::, *note OMP_PROC_BIND:: 1511 1512 1513 File: libgomp.info, Node: GOMP_DEBUG, Next: GOMP_STACKSIZE, Prev: GOMP_CPU_AFFINITY, Up: Environment Variables 1514 1515 3.16 'GOMP_DEBUG' - Enable debugging output 1516 =========================================== 1517 1518 _Description_: 1519 Enable debugging output. The variable should be set to '0' 1520 (disabled, also the default if not set), or '1' (enabled). 1521 1522 If enabled, some debugging output will be printed during execution. 1523 This is currently not specified in more detail, and subject to 1524 change. 1525 1526 1527 File: libgomp.info, Node: GOMP_STACKSIZE, Next: GOMP_SPINCOUNT, Prev: GOMP_DEBUG, Up: Environment Variables 1528 1529 3.17 'GOMP_STACKSIZE' - Set default thread stack size 1530 ===================================================== 1531 1532 _Description_: 1533 Set the default thread stack size in kilobytes. This is different 1534 from 'pthread_attr_setstacksize' which gets the number of bytes as 1535 an argument. If the stack size cannot be set due to system 1536 constraints, an error is reported and the initial stack size is 1537 left unchanged. If undefined, the stack size is system dependent. 1538 1539 _See also_: 1540 *note OMP_STACKSIZE:: 1541 1542 _Reference_: 1543 GCC Patches Mailinglist 1544 (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00493.html), GCC 1545 Patches Mailinglist 1546 (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00496.html) 1547 1548 1549 File: libgomp.info, Node: GOMP_SPINCOUNT, Next: GOMP_RTEMS_THREAD_POOLS, Prev: GOMP_STACKSIZE, Up: Environment Variables 1550 1551 3.18 'GOMP_SPINCOUNT' - Set the busy-wait spin count 1552 ==================================================== 1553 1554 _Description_: 1555 Determines how long a threads waits actively with consuming CPU 1556 power before waiting passively without consuming CPU power. The 1557 value may be either 'INFINITE', 'INFINITY' to always wait actively 1558 or an integer which gives the number of spins of the busy-wait 1559 loop. The integer may optionally be followed by the following 1560 suffixes acting as multiplication factors: 'k' (kilo, thousand), 1561 'M' (mega, million), 'G' (giga, billion), or 'T' (tera, trillion). 1562 If undefined, 0 is used when 'OMP_WAIT_POLICY' is 'PASSIVE', 1563 300,000 is used when 'OMP_WAIT_POLICY' is undefined and 30 billion 1564 is used when 'OMP_WAIT_POLICY' is 'ACTIVE'. If there are more 1565 OpenMP threads than available CPUs, 1000 and 100 spins are used for 1566 'OMP_WAIT_POLICY' being 'ACTIVE' or undefined, respectively; unless 1567 the 'GOMP_SPINCOUNT' is lower or 'OMP_WAIT_POLICY' is 'PASSIVE'. 1568 1569 _See also_: 1570 *note OMP_WAIT_POLICY:: 1571 1572 1573 File: libgomp.info, Node: GOMP_RTEMS_THREAD_POOLS, Prev: GOMP_SPINCOUNT, Up: Environment Variables 1574 1575 3.19 'GOMP_RTEMS_THREAD_POOLS' - Set the RTEMS specific thread pools 1576 ==================================================================== 1577 1578 _Description_: 1579 This environment variable is only used on the RTEMS real-time 1580 operating system. It determines the scheduler instance specific 1581 thread pools. The format for 'GOMP_RTEMS_THREAD_POOLS' is a list 1582 of optional '<thread-pool-count>[$<priority>]@<scheduler-name>' 1583 configurations separated by ':' where: 1584 * '<thread-pool-count>' is the thread pool count for this 1585 scheduler instance. 1586 * '$<priority>' is an optional priority for the worker threads 1587 of a thread pool according to 'pthread_setschedparam'. In 1588 case a priority value is omitted, then a worker thread will 1589 inherit the priority of the OpenMP master thread that created 1590 it. The priority of the worker thread is not changed after 1591 creation, even if a new OpenMP master thread using the worker 1592 has a different priority. 1593 * '@<scheduler-name>' is the scheduler instance name according 1594 to the RTEMS application configuration. 1595 In case no thread pool configuration is specified for a scheduler 1596 instance, then each OpenMP master thread of this scheduler instance 1597 will use its own dynamically allocated thread pool. To limit the 1598 worker thread count of the thread pools, each OpenMP master thread 1599 must call 'omp_set_num_threads'. 1600 _Example_: 1601 Lets suppose we have three scheduler instances 'IO', 'WRK0', and 1602 'WRK1' with 'GOMP_RTEMS_THREAD_POOLS' set to '"1@WRK0:3$4@WRK1"'. 1603 Then there are no thread pool restrictions for scheduler instance 1604 'IO'. In the scheduler instance 'WRK0' there is one thread pool 1605 available. Since no priority is specified for this scheduler 1606 instance, the worker thread inherits the priority of the OpenMP 1607 master thread that created it. In the scheduler instance 'WRK1' 1608 there are three thread pools available and their worker threads run 1609 at priority four. 1610 1611 1612 File: libgomp.info, Node: Enabling OpenACC, Next: OpenACC Runtime Library Routines, Prev: Environment Variables, Up: Top 1613 1614 4 Enabling OpenACC 1615 ****************** 1616 1617 To activate the OpenACC extensions for C/C++ and Fortran, the 1618 compile-time flag '-fopenacc' must be specified. This enables the 1619 OpenACC directive '#pragma acc' in C/C++ and '!$accp' directives in free 1620 form, 'c$acc', '*$acc' and '!$acc' directives in fixed form, '!$' 1621 conditional compilation sentinels in free form and 'c$', '*$' and '!$' 1622 sentinels in fixed form, for Fortran. The flag also arranges for 1623 automatic linking of the OpenACC runtime library (*note OpenACC Runtime 1624 Library Routines::). 1625 1626 A complete description of all OpenACC directives accepted may be 1627 found in the OpenACC (http://www.openacc.org/) Application Programming 1628 Interface manual, version 2.0. 1629 1630 Note that this is an experimental feature and subject to change in 1631 future versions of GCC. See <https://gcc.gnu.org/wiki/OpenACC> for more 1632 information. 1633 1634 1635 File: libgomp.info, Node: OpenACC Runtime Library Routines, Next: OpenACC Environment Variables, Prev: Enabling OpenACC, Up: Top 1636 1637 5 OpenACC Runtime Library Routines 1638 ********************************** 1639 1640 The runtime routines described here are defined by section 3 of the 1641 OpenACC specifications in version 2.0. They have C linkage, and do not 1642 throw exceptions. Generally, they are available only for the host, with 1643 the exception of 'acc_on_device', which is available for both the host 1644 and the acceleration device. 1645 1646 * Menu: 1647 1648 * acc_get_num_devices:: Get number of devices for the given device 1649 type. 1650 * acc_set_device_type:: Set type of device accelerator to use. 1651 * acc_get_device_type:: Get type of device accelerator to be used. 1652 * acc_set_device_num:: Set device number to use. 1653 * acc_get_device_num:: Get device number to be used. 1654 * acc_async_test:: Tests for completion of a specific asynchronous 1655 operation. 1656 * acc_async_test_all:: Tests for completion of all asychronous 1657 operations. 1658 * acc_wait:: Wait for completion of a specific asynchronous 1659 operation. 1660 * acc_wait_all:: Waits for completion of all asyncrhonous 1661 operations. 1662 * acc_wait_all_async:: Wait for completion of all asynchronous 1663 operations. 1664 * acc_wait_async:: Wait for completion of asynchronous operations. 1665 * acc_init:: Initialize runtime for a specific device type. 1666 * acc_shutdown:: Shuts down the runtime for a specific device 1667 type. 1668 * acc_on_device:: Whether executing on a particular device 1669 * acc_malloc:: Allocate device memory. 1670 * acc_free:: Free device memory. 1671 * acc_copyin:: Allocate device memory and copy host memory to 1672 it. 1673 * acc_present_or_copyin:: If the data is not present on the device, 1674 allocate device memory and copy from host 1675 memory. 1676 * acc_create:: Allocate device memory and map it to host 1677 memory. 1678 * acc_present_or_create:: If the data is not present on the device, 1679 allocate device memory and map it to host 1680 memory. 1681 * acc_copyout:: Copy device memory to host memory. 1682 * acc_delete:: Free device memory. 1683 * acc_update_device:: Update device memory from mapped host memory. 1684 * acc_update_self:: Update host memory from mapped device memory. 1685 * acc_map_data:: Map previously allocated device memory to host 1686 memory. 1687 * acc_unmap_data:: Unmap device memory from host memory. 1688 * acc_deviceptr:: Get device pointer associated with specific 1689 host address. 1690 * acc_hostptr:: Get host pointer associated with specific 1691 device address. 1692 * acc_is_present:: Indiciate whether host variable / array is 1693 present on device. 1694 * acc_memcpy_to_device:: Copy host memory to device memory. 1695 * acc_memcpy_from_device:: Copy device memory to host memory. 1696 1697 API routines for target platforms. 1698 1699 * acc_get_current_cuda_device:: Get CUDA device handle. 1700 * acc_get_current_cuda_context::Get CUDA context handle. 1701 * acc_get_cuda_stream:: Get CUDA stream handle. 1702 * acc_set_cuda_stream:: Set CUDA stream handle. 1703 1704 1705 File: libgomp.info, Node: acc_get_num_devices, Next: acc_set_device_type, Up: OpenACC Runtime Library Routines 1706 1707 5.1 'acc_get_num_devices' - Get number of devices for given device type 1708 ======================================================================= 1709 1710 _Description_ 1711 This function returns a value indicating the number of devices 1712 available for the device type specified in DEVICETYPE. 1713 1714 _C/C++_: 1715 _Prototype_: 'int acc_get_num_devices(acc_device_t devicetype);' 1716 1717 _Fortran_: 1718 _Interface_: 'integer function acc_get_num_devices(devicetype)' 1719 'integer(kind=acc_device_kind) devicetype' 1720 1721 _Reference_: 1722 OpenACC specification v2.0 (http://www.openacc.org/), section 1723 3.2.1. 1724 1725 1726 File: libgomp.info, Node: acc_set_device_type, Next: acc_get_device_type, Prev: acc_get_num_devices, Up: OpenACC Runtime Library Routines 1727 1728 5.2 'acc_set_device_type' - Set type of device accelerator to use. 1729 ================================================================== 1730 1731 _Description_ 1732 This function indicates to the runtime library which device typr, 1733 specified in DEVICETYPE, to use when executing a parallel or 1734 kernels region. 1735 1736 _C/C++_: 1737 _Prototype_: 'acc_set_device_type(acc_device_t devicetype);' 1738 1739 _Fortran_: 1740 _Interface_: 'subroutine acc_set_device_type(devicetype)' 1741 'integer(kind=acc_device_kind) devicetype' 1742 1743 _Reference_: 1744 OpenACC specification v2.0 (http://www.openacc.org/), section 1745 3.2.2. 1746 1747 1748 File: libgomp.info, Node: acc_get_device_type, Next: acc_set_device_num, Prev: acc_set_device_type, Up: OpenACC Runtime Library Routines 1749 1750 5.3 'acc_get_device_type' - Get type of device accelerator to be used. 1751 ====================================================================== 1752 1753 _Description_ 1754 This function returns what device type will be used when executing 1755 a parallel or kernels region. 1756 1757 _C/C++_: 1758 _Prototype_: 'acc_device_t acc_get_device_type(void);' 1759 1760 _Fortran_: 1761 _Interface_: 'function acc_get_device_type(void)' 1762 'integer(kind=acc_device_kind) acc_get_device_type' 1763 1764 _Reference_: 1765 OpenACC specification v2.0 (http://www.openacc.org/), section 1766 3.2.3. 1767 1768 1769 File: libgomp.info, Node: acc_set_device_num, Next: acc_get_device_num, Prev: acc_get_device_type, Up: OpenACC Runtime Library Routines 1770 1771 5.4 'acc_set_device_num' - Set device number to use. 1772 ==================================================== 1773 1774 _Description_ 1775 This function will indicate to the runtime which device number, 1776 specified by NUM, associated with the specifed device type 1777 DEVICETYPE. 1778 1779 _C/C++_: 1780 _Prototype_: 'acc_set_device_num(int num, acc_device_t devicetype);' 1781 1782 _Fortran_: 1783 _Interface_: 'subroutine acc_set_device_num(devicenum, devicetype)' 1784 'integer devicenum' 1785 'integer(kind=acc_device_kind) devicetype' 1786 1787 _Reference_: 1788 OpenACC specification v2.0 (http://www.openacc.org/), section 1789 3.2.4. 1790 1791 1792 File: libgomp.info, Node: acc_get_device_num, Next: acc_async_test, Prev: acc_set_device_num, Up: OpenACC Runtime Library Routines 1793 1794 5.5 'acc_get_device_num' - Get device number to be used. 1795 ======================================================== 1796 1797 _Description_ 1798 This function returns which device number associated with the 1799 specified device type DEVICETYPE, will be used when executing a 1800 parallel or kernels region. 1801 1802 _C/C++_: 1803 _Prototype_: 'int acc_get_device_num(acc_device_t devicetype);' 1804 1805 _Fortran_: 1806 _Interface_: 'function acc_get_device_num(devicetype)' 1807 'integer(kind=acc_device_kind) devicetype' 1808 'integer acc_get_device_num' 1809 1810 _Reference_: 1811 OpenACC specification v2.0 (http://www.openacc.org/), section 1812 3.2.5. 1813 1814 1815 File: libgomp.info, Node: acc_async_test, Next: acc_async_test_all, Prev: acc_get_device_num, Up: OpenACC Runtime Library Routines 1816 1817 5.6 'acc_async_test' - Test for completion of a specific asynchronous operation. 1818 ================================================================================ 1819 1820 _Description_ 1821 This function tests for completion of the asynchrounous operation 1822 specified in ARG. In C/C++, a non-zero value will be returned to 1823 indicate the specified asynchronous operation has completed. While 1824 Fortran will return a 'true'. If the asynchrounous operation has 1825 not completed, C/C++ returns a zero and Fortran returns a 'false'. 1826 1827 _C/C++_: 1828 _Prototype_: 'int acc_async_test(int arg);' 1829 1830 _Fortran_: 1831 _Interface_: 'function acc_async_test(arg)' 1832 'integer(kind=acc_handle_kind) arg' 1833 'logical acc_async_test' 1834 1835 _Reference_: 1836 OpenACC specification v2.0 (http://www.openacc.org/), section 1837 3.2.6. 1838 1839 1840 File: libgomp.info, Node: acc_async_test_all, Next: acc_wait, Prev: acc_async_test, Up: OpenACC Runtime Library Routines 1841 1842 5.7 'acc_async_test_all' - Tests for completion of all asynchronous operations. 1843 =============================================================================== 1844 1845 _Description_ 1846 This function tests for completion of all asynchrounous operations. 1847 In C/C++, a non-zero value will be returned to indicate all 1848 asynchronous operations have completed. While Fortran will return 1849 a 'true'. If any asynchronous operation has not completed, C/C++ 1850 returns a zero and Fortran returns a 'false'. 1851 1852 _C/C++_: 1853 _Prototype_: 'int acc_async_test_all(void);' 1854 1855 _Fortran_: 1856 _Interface_: 'function acc_async_test()' 1857 'logical acc_get_device_num' 1858 1859 _Reference_: 1860 OpenACC specification v2.0 (http://www.openacc.org/), section 1861 3.2.7. 1862 1863 1864 File: libgomp.info, Node: acc_wait, Next: acc_wait_all, Prev: acc_async_test_all, Up: OpenACC Runtime Library Routines 1865 1866 5.8 'acc_wait' - Wait for completion of a specific asynchronous operation. 1867 ========================================================================== 1868 1869 _Description_ 1870 This function waits for completion of the asynchronous operation 1871 specified in ARG. 1872 1873 _C/C++_: 1874 _Prototype_: 'acc_wait(arg);' 1875 1876 _Fortran_: 1877 _Interface_: 'subroutine acc_wait(arg)' 1878 'integer(acc_handle_kind) arg' 1879 1880 _Reference_: 1881 OpenACC specification v2.0 (http://www.openacc.org/), section 1882 3.2.8. 1883 1884 1885 File: libgomp.info, Node: acc_wait_all, Next: acc_wait_all_async, Prev: acc_wait, Up: OpenACC Runtime Library Routines 1886 1887 5.9 'acc_wait_all' - Waits for completion of all asynchronous operations. 1888 ========================================================================= 1889 1890 _Description_ 1891 This function waits for the completion of all asynchronous 1892 operations. 1893 1894 _C/C++_: 1895 _Prototype_: 'acc_wait_all(void);' 1896 1897 _Fortran_: 1898 _Interface_: 'subroutine acc_wait_async()' 1899 1900 _Reference_: 1901 OpenACC specification v2.0 (http://www.openacc.org/), section 1902 3.2.10. 1903 1904 1905 File: libgomp.info, Node: acc_wait_all_async, Next: acc_wait_async, Prev: acc_wait_all, Up: OpenACC Runtime Library Routines 1906 1907 5.10 'acc_wait_all_async' - Wait for completion of all asynchronous operations. 1908 =============================================================================== 1909 1910 _Description_ 1911 This function enqueues a wait operation on the queue ASYNC for any 1912 and all asynchronous operations that have been previously enqueued 1913 on any queue. 1914 1915 _C/C++_: 1916 _Prototype_: 'acc_wait_all_async(int async);' 1917 1918 _Fortran_: 1919 _Interface_: 'subroutine acc_wait_all_async(async)' 1920 'integer(acc_handle_kind) async' 1921 1922 _Reference_: 1923 OpenACC specification v2.0 (http://www.openacc.org/), section 1924 3.2.11. 1925 1926 1927 File: libgomp.info, Node: acc_wait_async, Next: acc_init, Prev: acc_wait_all_async, Up: OpenACC Runtime Library Routines 1928 1929 5.11 'acc_wait_async' - Wait for completion of asynchronous operations. 1930 ======================================================================= 1931 1932 _Description_ 1933 This function enqueues a wait operation on queue ASYNC for any and 1934 all asynchronous operations enqueued on queue ARG. 1935 1936 _C/C++_: 1937 _Prototype_: 'acc_wait_async(int arg, int async);' 1938 1939 _Fortran_: 1940 _Interface_: 'subroutine acc_wait_async(arg, async)' 1941 'integer(acc_handle_kind) arg, async' 1942 1943 _Reference_: 1944 OpenACC specification v2.0 (http://www.openacc.org/), section 1945 3.2.9. 1946 1947 1948 File: libgomp.info, Node: acc_init, Next: acc_shutdown, Prev: acc_wait_async, Up: OpenACC Runtime Library Routines 1949 1950 5.12 'acc_init' - Initialize runtime for a specific device type. 1951 ================================================================ 1952 1953 _Description_ 1954 This function initializes the runtime for the device type specified 1955 in DEVICETYPE. 1956 1957 _C/C++_: 1958 _Prototype_: 'acc_init(acc_device_t devicetype);' 1959 1960 _Fortran_: 1961 _Interface_: 'subroutine acc_init(devicetype)' 1962 'integer(acc_device_kind) devicetype' 1963 1964 _Reference_: 1965 OpenACC specification v2.0 (http://www.openacc.org/), section 1966 3.2.12. 1967 1968 1969 File: libgomp.info, Node: acc_shutdown, Next: acc_on_device, Prev: acc_init, Up: OpenACC Runtime Library Routines 1970 1971 5.13 'acc_shutdown' - Shuts down the runtime for a specific device type. 1972 ======================================================================== 1973 1974 _Description_ 1975 This function shuts down the runtime for the device type specified 1976 in DEVICETYPE. 1977 1978 _C/C++_: 1979 _Prototype_: 'acc_shutdown(acc_device_t devicetype);' 1980 1981 _Fortran_: 1982 _Interface_: 'subroutine acc_shutdown(devicetype)' 1983 'integer(acc_device_kind) devicetype' 1984 1985 _Reference_: 1986 OpenACC specification v2.0 (http://www.openacc.org/), section 1987 3.2.13. 1988 1989 1990 File: libgomp.info, Node: acc_on_device, Next: acc_malloc, Prev: acc_shutdown, Up: OpenACC Runtime Library Routines 1991 1992 5.14 'acc_on_device' - Whether executing on a particular device 1993 =============================================================== 1994 1995 _Description_: 1996 This function returns whether the program is executing on a 1997 particular device specified in DEVICETYPE. In C/C++ a non-zero 1998 value is returned to indicate the device is execiting on the 1999 specified device type. In Fortran, 'true' will be returned. If 2000 the program is not executing on the specified device type C/C++ 2001 will return a zero, while Fortran will return 'false'. 2002 2003 _C/C++_: 2004 _Prototype_: 'acc_on_device(acc_device_t devicetype);' 2005 2006 _Fortran_: 2007 _Interface_: 'function acc_on_device(devicetype)' 2008 'integer(acc_device_kind) devicetype' 2009 'logical acc_on_device' 2010 2011 _Reference_: 2012 OpenACC specification v2.0 (http://www.openacc.org/), section 2013 3.2.14. 2014 2015 2016 File: libgomp.info, Node: acc_malloc, Next: acc_free, Prev: acc_on_device, Up: OpenACC Runtime Library Routines 2017 2018 5.15 'acc_malloc' - Allocate device memory. 2019 =========================================== 2020 2021 _Description_ 2022 This function allocates LEN bytes of device memory. It returns the 2023 device address of the allocated memory. 2024 2025 _C/C++_: 2026 _Prototype_: 'd_void* acc_malloc(size_t len);' 2027 2028 _Reference_: 2029 OpenACC specification v2.0 (http://www.openacc.org/), section 2030 3.2.15. 2031 2032 2033 File: libgomp.info, Node: acc_free, Next: acc_copyin, Prev: acc_malloc, Up: OpenACC Runtime Library Routines 2034 2035 5.16 'acc_free' - Free device memory. 2036 ===================================== 2037 2038 _Description_ 2039 Free previously allocated device memory at the device address 'a'. 2040 2041 _C/C++_: 2042 _Prototype_: 'acc_free(d_void *a);' 2043 2044 _Reference_: 2045 OpenACC specification v2.0 (http://www.openacc.org/), section 2046 3.2.16. 2047 2048 2049 File: libgomp.info, Node: acc_copyin, Next: acc_present_or_copyin, Prev: acc_free, Up: OpenACC Runtime Library Routines 2050 2051 5.17 'acc_copyin' - Allocate device memory and copy host memory to it. 2052 ====================================================================== 2053 2054 _Description_ 2055 In C/C++, this function allocates LEN bytes of device memory and 2056 maps it to the specified host address in A. The device address of 2057 the newly allocated device memory is returned. 2058 2059 In Fortran, two (2) forms are supported. In the first form, A 2060 specifies a contiguous array section. The second form A specifies 2061 a variable or array element and LEN specifies the length in bytes. 2062 2063 _C/C++_: 2064 _Prototype_: 'void *acc_copyin(h_void *a, size_t len);' 2065 2066 _Fortran_: 2067 _Interface_: 'subroutine acc_copyin(a)' 2068 'type, dimension(:[,:]...) :: a' 2069 _Interface_: 'subroutine acc_copyin(a, len)' 2070 'type, dimension(:[,:]...) :: a' 2071 'integer len' 2072 2073 _Reference_: 2074 OpenACC specification v2.0 (http://www.openacc.org/), section 2075 3.2.17. 2076 2077 2078 File: libgomp.info, Node: acc_present_or_copyin, Next: acc_create, Prev: acc_copyin, Up: OpenACC Runtime Library Routines 2079 2080 5.18 'acc_present_or_copyin' - If the data is not present on the device, allocate device memory and copy from host memory. 2081 ========================================================================================================================== 2082 2083 _Description_ 2084 This function tests if the host data specifed by A and of length 2085 LEN is present or not. If it is not present, then device memory 2086 will be allocated and the host memory copied. The device address 2087 of the newly allocated device memory is returned. 2088 2089 In Fortran, two (2) forms are supported. In the first form, A 2090 specifies a contiguous array section. The second form A specifies 2091 a variable or array element and LEN specifies the length in bytes. 2092 2093 _C/C++_: 2094 _Prototype_: 'void *acc_present_or_copyin(h_void *a, size_t len);' 2095 _Prototype_: 'void *acc_pcopyin(h_void *a, size_t len);' 2096 2097 _Fortran_: 2098 _Interface_: 'subroutine acc_present_or_copyin(a)' 2099 'type, dimension(:[,:]...) :: a' 2100 _Interface_: 'subroutine acc_present_or_copyin(a, len)' 2101 'type, dimension(:[,:]...) :: a' 2102 'integer len' 2103 _Interface_: 'subroutine acc_pcopyin(a)' 2104 'type, dimension(:[,:]...) :: a' 2105 _Interface_: 'subroutine acc_pcopyin(a, len)' 2106 'type, dimension(:[,:]...) :: a' 2107 'integer len' 2108 2109 _Reference_: 2110 OpenACC specification v2.0 (http://www.openacc.org/), section 2111 3.2.18. 2112 2113 2114 File: libgomp.info, Node: acc_create, Next: acc_present_or_create, Prev: acc_present_or_copyin, Up: OpenACC Runtime Library Routines 2115 2116 5.19 'acc_create' - Allocate device memory and map it to host memory. 2117 ===================================================================== 2118 2119 _Description_ 2120 This function allocates device memory and maps it to host memory 2121 specified by the host address A with a length of LEN bytes. In 2122 C/C++, the function returns the device address of the allocated 2123 device memory. 2124 2125 In Fortran, two (2) forms are supported. In the first form, A 2126 specifies a contiguous array section. The second form A specifies 2127 a variable or array element and LEN specifies the length in bytes. 2128 2129 _C/C++_: 2130 _Prototype_: 'void *acc_create(h_void *a, size_t len);' 2131 2132 _Fortran_: 2133 _Interface_: 'subroutine acc_create(a)' 2134 'type, dimension(:[,:]...) :: a' 2135 _Interface_: 'subroutine acc_create(a, len)' 2136 'type, dimension(:[,:]...) :: a' 2137 'integer len' 2138 2139 _Reference_: 2140 OpenACC specification v2.0 (http://www.openacc.org/), section 2141 3.2.19. 2142 2143 2144 File: libgomp.info, Node: acc_present_or_create, Next: acc_copyout, Prev: acc_create, Up: OpenACC Runtime Library Routines 2145 2146 5.20 'acc_present_or_create' - If the data is not present on the device, allocate device memory and map it to host memory. 2147 ========================================================================================================================== 2148 2149 _Description_ 2150 This function tests if the host data specifed by A and of length 2151 LEN is present or not. If it is not present, then device memory 2152 will be allocated and mapped to host memory. In C/C++, the device 2153 address of the newly allocated device memory is returned. 2154 2155 In Fortran, two (2) forms are supported. In the first form, A 2156 specifies a contiguous array section. The second form A specifies 2157 a variable or array element and LEN specifies the length in bytes. 2158 2159 _C/C++_: 2160 _Prototype_: 'void *acc_present_or_create(h_void *a, size_t len)' 2161 _Prototype_: 'void *acc_pcreate(h_void *a, size_t len)' 2162 2163 _Fortran_: 2164 _Interface_: 'subroutine acc_present_or_create(a)' 2165 'type, dimension(:[,:]...) :: a' 2166 _Interface_: 'subroutine acc_present_or_create(a, len)' 2167 'type, dimension(:[,:]...) :: a' 2168 'integer len' 2169 _Interface_: 'subroutine acc_pcreate(a)' 2170 'type, dimension(:[,:]...) :: a' 2171 _Interface_: 'subroutine acc_pcreate(a, len)' 2172 'type, dimension(:[,:]...) :: a' 2173 'integer len' 2174 2175 _Reference_: 2176 OpenACC specification v2.0 (http://www.openacc.org/), section 2177 3.2.20. 2178 2179 2180 File: libgomp.info, Node: acc_copyout, Next: acc_delete, Prev: acc_present_or_create, Up: OpenACC Runtime Library Routines 2181 2182 5.21 'acc_copyout' - Copy device memory to host memory. 2183 ======================================================= 2184 2185 _Description_ 2186 This function copies mapped device memory to host memory which is 2187 specified by host address A for a length LEN bytes in C/C++. 2188 2189 In Fortran, two (2) forms are supported. In the first form, A 2190 specifies a contiguous array section. The second form A specifies 2191 a variable or array element and LEN specifies the length in bytes. 2192 2193 _C/C++_: 2194 _Prototype_: 'acc_copyout(h_void *a, size_t len);' 2195 2196 _Fortran_: 2197 _Interface_: 'subroutine acc_copyout(a)' 2198 'type, dimension(:[,:]...) :: a' 2199 _Interface_: 'subroutine acc_copyout(a, len)' 2200 'type, dimension(:[,:]...) :: a' 2201 'integer len' 2202 2203 _Reference_: 2204 OpenACC specification v2.0 (http://www.openacc.org/), section 2205 3.2.21. 2206 2207 2208 File: libgomp.info, Node: acc_delete, Next: acc_update_device, Prev: acc_copyout, Up: OpenACC Runtime Library Routines 2209 2210 5.22 'acc_delete' - Free device memory. 2211 ======================================= 2212 2213 _Description_ 2214 This function frees previously allocated device memory specified by 2215 the device address A and the length of LEN bytes. 2216 2217 In Fortran, two (2) forms are supported. In the first form, A 2218 specifies a contiguous array section. The second form A specifies 2219 a variable or array element and LEN specifies the length in bytes. 2220 2221 _C/C++_: 2222 _Prototype_: 'acc_delete(h_void *a, size_t len);' 2223 2224 _Fortran_: 2225 _Interface_: 'subroutine acc_delete(a)' 2226 'type, dimension(:[,:]...) :: a' 2227 _Interface_: 'subroutine acc_delete(a, len)' 2228 'type, dimension(:[,:]...) :: a' 2229 'integer len' 2230 2231 _Reference_: 2232 OpenACC specification v2.0 (http://www.openacc.org/), section 2233 3.2.22. 2234 2235 2236 File: libgomp.info, Node: acc_update_device, Next: acc_update_self, Prev: acc_delete, Up: OpenACC Runtime Library Routines 2237 2238 5.23 'acc_update_device' - Update device memory from mapped host memory. 2239 ======================================================================== 2240 2241 _Description_ 2242 This function updates the device copy from the previously mapped 2243 host memory. The host memory is specified with the host address A 2244 and a length of LEN bytes. 2245 2246 In Fortran, two (2) forms are supported. In the first form, A 2247 specifies a contiguous array section. The second form A specifies 2248 a variable or array element and LEN specifies the length in bytes. 2249 2250 _C/C++_: 2251 _Prototype_: 'acc_update_device(h_void *a, size_t len);' 2252 2253 _Fortran_: 2254 _Interface_: 'subroutine acc_update_device(a)' 2255 'type, dimension(:[,:]...) :: a' 2256 _Interface_: 'subroutine acc_update_device(a, len)' 2257 'type, dimension(:[,:]...) :: a' 2258 'integer len' 2259 2260 _Reference_: 2261 OpenACC specification v2.0 (http://www.openacc.org/), section 2262 3.2.23. 2263 2264 2265 File: libgomp.info, Node: acc_update_self, Next: acc_map_data, Prev: acc_update_device, Up: OpenACC Runtime Library Routines 2266 2267 5.24 'acc_update_self' - Update host memory from mapped device memory. 2268 ====================================================================== 2269 2270 _Description_ 2271 This function updates the host copy from the previously mapped 2272 device memory. The host memory is specified with the host address 2273 A and a length of LEN bytes. 2274 2275 In Fortran, two (2) forms are supported. In the first form, A 2276 specifies a contiguous array section. The second form A specifies 2277 a variable or array element and LEN specifies the length in bytes. 2278 2279 _C/C++_: 2280 _Prototype_: 'acc_update_self(h_void *a, size_t len);' 2281 2282 _Fortran_: 2283 _Interface_: 'subroutine acc_update_self(a)' 2284 'type, dimension(:[,:]...) :: a' 2285 _Interface_: 'subroutine acc_update_self(a, len)' 2286 'type, dimension(:[,:]...) :: a' 2287 'integer len' 2288 2289 _Reference_: 2290 OpenACC specification v2.0 (http://www.openacc.org/), section 2291 3.2.24. 2292 2293 2294 File: libgomp.info, Node: acc_map_data, Next: acc_unmap_data, Prev: acc_update_self, Up: OpenACC Runtime Library Routines 2295 2296 5.25 'acc_map_data' - Map previously allocated device memory to host memory. 2297 ============================================================================ 2298 2299 _Description_ 2300 This function maps previously allocated device and host memory. 2301 The device memory is specified with the device address D. The host 2302 memory is specified with the host address H and a length of LEN. 2303 2304 _C/C++_: 2305 _Prototype_: 'acc_map_data(h_void *h, d_void *d, size_t len);' 2306 2307 _Reference_: 2308 OpenACC specification v2.0 (http://www.openacc.org/), section 2309 3.2.25. 2310 2311 2312 File: libgomp.info, Node: acc_unmap_data, Next: acc_deviceptr, Prev: acc_map_data, Up: OpenACC Runtime Library Routines 2313 2314 5.26 'acc_unmap_data' - Unmap device memory from host memory. 2315 ============================================================= 2316 2317 _Description_ 2318 This function unmaps previously mapped device and host memory. The 2319 latter specified by H. 2320 2321 _C/C++_: 2322 _Prototype_: 'acc_unmap_data(h_void *h);' 2323 2324 _Reference_: 2325 OpenACC specification v2.0 (http://www.openacc.org/), section 2326 3.2.26. 2327 2328 2329 File: libgomp.info, Node: acc_deviceptr, Next: acc_hostptr, Prev: acc_unmap_data, Up: OpenACC Runtime Library Routines 2330 2331 5.27 'acc_deviceptr' - Get device pointer associated with specific host address. 2332 ================================================================================ 2333 2334 _Description_ 2335 This function returns the device address that has been mapped to 2336 the host address specified by H. 2337 2338 _C/C++_: 2339 _Prototype_: 'void *acc_deviceptr(h_void *h);' 2340 2341 _Reference_: 2342 OpenACC specification v2.0 (http://www.openacc.org/), section 2343 3.2.27. 2344 2345 2346 File: libgomp.info, Node: acc_hostptr, Next: acc_is_present, Prev: acc_deviceptr, Up: OpenACC Runtime Library Routines 2347 2348 5.28 'acc_hostptr' - Get host pointer associated with specific device address. 2349 ============================================================================== 2350 2351 _Description_ 2352 This function returns the host address that has been mapped to the 2353 device address specified by D. 2354 2355 _C/C++_: 2356 _Prototype_: 'void *acc_hostptr(d_void *d);' 2357 2358 _Reference_: 2359 OpenACC specification v2.0 (http://www.openacc.org/), section 2360 3.2.28. 2361 2362 2363 File: libgomp.info, Node: acc_is_present, Next: acc_memcpy_to_device, Prev: acc_hostptr, Up: OpenACC Runtime Library Routines 2364 2365 5.29 'acc_is_present' - Indicate whether host variable / array is present on device. 2366 ==================================================================================== 2367 2368 _Description_ 2369 This function indicates whether the specified host address in A and 2370 a length of LEN bytes is present on the device. In C/C++, a 2371 non-zero value is returned to indicate the presence of the mapped 2372 memory on the device. A zero is returned to indicate the memory is 2373 not mapped on the device. 2374 2375 In Fortran, two (2) forms are supported. In the first form, A 2376 specifies a contiguous array section. The second form A specifies 2377 a variable or array element and LEN specifies the length in bytes. 2378 If the host memory is mapped to device memory, then a 'true' is 2379 returned. Otherwise, a 'false' is return to indicate the mapped 2380 memory is not present. 2381 2382 _C/C++_: 2383 _Prototype_: 'int acc_is_present(h_void *a, size_t len);' 2384 2385 _Fortran_: 2386 _Interface_: 'function acc_is_present(a)' 2387 'type, dimension(:[,:]...) :: a' 2388 'logical acc_is_present' 2389 _Interface_: 'function acc_is_present(a, len)' 2390 'type, dimension(:[,:]...) :: a' 2391 'integer len' 2392 'logical acc_is_present' 2393 2394 _Reference_: 2395 OpenACC specification v2.0 (http://www.openacc.org/), section 2396 3.2.29. 2397 2398 2399 File: libgomp.info, Node: acc_memcpy_to_device, Next: acc_memcpy_from_device, Prev: acc_is_present, Up: OpenACC Runtime Library Routines 2400 2401 5.30 'acc_memcpy_to_device' - Copy host memory to device memory. 2402 ================================================================ 2403 2404 _Description_ 2405 This function copies host memory specified by host address of SRC 2406 to device memory specified by the device address DEST for a length 2407 of BYTES bytes. 2408 2409 _C/C++_: 2410 _Prototype_: 'acc_memcpy_to_device(d_void *dest, h_void *src, size_t 2411 bytes);' 2412 2413 _Reference_: 2414 OpenACC specification v2.0 (http://www.openacc.org/), section 2415 3.2.30. 2416 2417 2418 File: libgomp.info, Node: acc_memcpy_from_device, Next: acc_get_current_cuda_device, Prev: acc_memcpy_to_device, Up: OpenACC Runtime Library Routines 2419 2420 5.31 'acc_memcpy_from_device' - Copy device memory to host memory. 2421 ================================================================== 2422 2423 _Description_ 2424 This function copies host memory specified by host address of SRC 2425 from device memory specified by the device address DEST for a 2426 length of BYTES bytes. 2427 2428 _C/C++_: 2429 _Prototype_: 'acc_memcpy_from_device(d_void *dest, h_void *src, 2430 size_t bytes);' 2431 2432 _Reference_: 2433 OpenACC specification v2.0 (http://www.openacc.org/), section 2434 3.2.31. 2435 2436 2437 File: libgomp.info, Node: acc_get_current_cuda_device, Next: acc_get_current_cuda_context, Prev: acc_memcpy_from_device, Up: OpenACC Runtime Library Routines 2438 2439 5.32 'acc_get_current_cuda_device' - Get CUDA device handle. 2440 ============================================================ 2441 2442 _Description_ 2443 This function returns the CUDA device handle. This handle is the 2444 same as used by the CUDA Runtime or Driver API's. 2445 2446 _C/C++_: 2447 _Prototype_: 'void *acc_get_current_cuda_device(void);' 2448 2449 _Reference_: 2450 OpenACC specification v2.0 (http://www.openacc.org/), section 2451 A.2.1.1. 2452 2453 2454 File: libgomp.info, Node: acc_get_current_cuda_context, Next: acc_get_cuda_stream, Prev: acc_get_current_cuda_device, Up: OpenACC Runtime Library Routines 2455 2456 5.33 'acc_get_current_cuda_context' - Get CUDA context handle. 2457 ============================================================== 2458 2459 _Description_ 2460 This function returns the CUDA context handle. This handle is the 2461 same as used by the CUDA Runtime or Driver API's. 2462 2463 _C/C++_: 2464 _Prototype_: 'acc_get_current_cuda_context(void);' 2465 2466 _Reference_: 2467 OpenACC specification v2.0 (http://www.openacc.org/), section 2468 A.2.1.2. 2469 2470 2471 File: libgomp.info, Node: acc_get_cuda_stream, Next: acc_set_cuda_stream, Prev: acc_get_current_cuda_context, Up: OpenACC Runtime Library Routines 2472 2473 5.34 'acc_get_cuda_stream' - Get CUDA stream handle. 2474 ==================================================== 2475 2476 _Description_ 2477 This function returns the CUDA stream handle. This handle is the 2478 same as used by the CUDA Runtime or Driver API's. 2479 2480 _C/C++_: 2481 _Prototype_: 'acc_get_cuda_stream(void);' 2482 2483 _Reference_: 2484 OpenACC specification v2.0 (http://www.openacc.org/), section 2485 A.2.1.3. 2486 2487 2488 File: libgomp.info, Node: acc_set_cuda_stream, Prev: acc_get_cuda_stream, Up: OpenACC Runtime Library Routines 2489 2490 5.35 'acc_set_cuda_stream' - Set CUDA stream handle. 2491 ==================================================== 2492 2493 _Description_ 2494 This function associates the stream handle specified by STREAM with 2495 the asynchronous value specified by ASYNC. 2496 2497 _C/C++_: 2498 _Prototype_: 'acc_set_cuda_stream(int async void *stream);' 2499 2500 _Reference_: 2501 OpenACC specification v2.0 (http://www.openacc.org/), section 2502 A.2.1.4. 2503 2504 2505 File: libgomp.info, Node: OpenACC Environment Variables, Next: CUDA Streams Usage, Prev: OpenACC Runtime Library Routines, Up: Top 2506 2507 6 OpenACC Environment Variables 2508 ******************************* 2509 2510 The variables 'ACC_DEVICE_TYPE' and 'ACC_DEVICE_NUM' are defined by 2511 section 4 of the OpenACC specification in version 2.0. The variable 2512 'GCC_ACC_NOTIFY' is used for diagnostic purposes. 2513 2514 * Menu: 2515 2516 * ACC_DEVICE_TYPE:: 2517 * ACC_DEVICE_NUM:: 2518 * GCC_ACC_NOTIFY:: 2519 2520 2521 File: libgomp.info, Node: ACC_DEVICE_TYPE, Next: ACC_DEVICE_NUM, Up: OpenACC Environment Variables 2522 2523 6.1 'ACC_DEVICE_TYPE' 2524 ===================== 2525 2526 _Reference_: 2527 OpenACC specification v2.0 (http://www.openacc.org/), section 4.1. 2528 2529 2530 File: libgomp.info, Node: ACC_DEVICE_NUM, Next: GCC_ACC_NOTIFY, Prev: ACC_DEVICE_TYPE, Up: OpenACC Environment Variables 2531 2532 6.2 'ACC_DEVICE_NUM' 2533 ==================== 2534 2535 _Reference_: 2536 OpenACC specification v2.0 (http://www.openacc.org/), section 4.2. 2537 2538 2539 File: libgomp.info, Node: GCC_ACC_NOTIFY, Prev: ACC_DEVICE_NUM, Up: OpenACC Environment Variables 2540 2541 6.3 'GCC_ACC_NOTIFY' 2542 ==================== 2543 2544 _Description_: 2545 Print debug information pertaining to the accelerator. 2546 2547 2548 File: libgomp.info, Node: CUDA Streams Usage, Next: OpenACC Library Interoperability, Prev: OpenACC Environment Variables, Up: Top 2549 2550 7 CUDA Streams Usage 2551 ******************** 2552 2553 This applies to the 'nvptx' plugin only. 2554 2555 The library provides elements that perform asynchronous movement of 2556 data and asynchronous operation of computing constructs. This 2557 asynchronous functionality is implemented by making use of CUDA 2558 streams(1). 2559 2560 The primary means by that the asychronous functionality is accessed 2561 is through the use of those OpenACC directives which make use of the 2562 'async' and 'wait' clauses. When the 'async' clause is first used with 2563 a directive, it creates a CUDA stream. If an 'async-argument' is used 2564 with the 'async' clause, then the stream is associated with the 2565 specified 'async-argument'. 2566 2567 Following the creation of an association between a CUDA stream and 2568 the 'async-argument' of an 'async' clause, both the 'wait' clause and 2569 the 'wait' directive can be used. When either the clause or directive 2570 is used after stream creation, it creates a rendezvous point whereby 2571 execution waits until all operations associated with the 2572 'async-argument', that is, stream, have completed. 2573 2574 Normally, the management of the streams that are created as a result 2575 of using the 'async' clause, is done without any intervention by the 2576 caller. This implies the association between the 'async-argument' and 2577 the CUDA stream will be maintained for the lifetime of the program. 2578 However, this association can be changed through the use of the library 2579 function 'acc_set_cuda_stream'. When the function 'acc_set_cuda_stream' 2580 is called, the CUDA stream that was originally associated with the 2581 'async' clause will be destroyed. Caution should be taken when changing 2582 the association as subsequent references to the 'async-argument' refer 2583 to a different CUDA stream. 2584 2585 ---------- Footnotes ---------- 2586 2587 (1) See "Stream Management" in "CUDA Driver API", TRM-06703-001, 2588 Version 5.5, for additional information 2589 2590 2591 File: libgomp.info, Node: OpenACC Library Interoperability, Next: The libgomp ABI, Prev: CUDA Streams Usage, Up: Top 2592 2593 8 OpenACC Library Interoperability 2594 ********************************** 2595 2596 8.1 Introduction 2597 ================ 2598 2599 The OpenACC library uses the CUDA Driver API, and may interact with 2600 programs that use the Runtime library directly, or another library based 2601 on the Runtime library, e.g., CUBLAS(1). This chapter describes the use 2602 cases and what changes are required in order to use both the OpenACC 2603 library and the CUBLAS and Runtime libraries within a program. 2604 2605 8.2 First invocation: NVIDIA CUBLAS library API 2606 =============================================== 2607 2608 In this first use case (see below), a function in the CUBLAS library is 2609 called prior to any of the functions in the OpenACC library. More 2610 specifically, the function 'cublasCreate()'. 2611 2612 When invoked, the function initializes the library and allocates the 2613 hardware resources on the host and the device on behalf of the caller. 2614 Once the initialization and allocation has completed, a handle is 2615 returned to the caller. The OpenACC library also requires 2616 initialization and allocation of hardware resources. Since the CUBLAS 2617 library has already allocated the hardware resources for the device, all 2618 that is left to do is to initialize the OpenACC library and acquire the 2619 hardware resources on the host. 2620 2621 Prior to calling the OpenACC function that initializes the library 2622 and allocate the host hardware resources, you need to acquire the device 2623 number that was allocated during the call to 'cublasCreate()'. The 2624 invoking of the runtime library function 'cudaGetDevice()' accomplishes 2625 this. Once acquired, the device number is passed along with the device 2626 type as parameters to the OpenACC library function 2627 'acc_set_device_num()'. 2628 2629 Once the call to 'acc_set_device_num()' has completed, the OpenACC 2630 library uses the context that was created during the call to 2631 'cublasCreate()'. In other words, both libraries will be sharing the 2632 same context. 2633 2634 /* Create the handle */ 2635 s = cublasCreate(&h); 2636 if (s != CUBLAS_STATUS_SUCCESS) 2637 { 2638 fprintf(stderr, "cublasCreate failed %d\n", s); 2639 exit(EXIT_FAILURE); 2640 } 2641 2642 /* Get the device number */ 2643 e = cudaGetDevice(&dev); 2644 if (e != cudaSuccess) 2645 { 2646 fprintf(stderr, "cudaGetDevice failed %d\n", e); 2647 exit(EXIT_FAILURE); 2648 } 2649 2650 /* Initialize OpenACC library and use device 'dev' */ 2651 acc_set_device_num(dev, acc_device_nvidia); 2652 2653 Use Case 1 2654 2655 8.3 First invocation: OpenACC library API 2656 ========================================= 2657 2658 In this second use case (see below), a function in the OpenACC library 2659 is called prior to any of the functions in the CUBLAS library. More 2660 specificially, the function 'acc_set_device_num()'. 2661 2662 In the use case presented here, the function 'acc_set_device_num()' 2663 is used to both initialize the OpenACC library and allocate the hardware 2664 resources on the host and the device. In the call to the function, the 2665 call parameters specify which device to use and what device type to use, 2666 i.e., 'acc_device_nvidia'. It should be noted that this is but one 2667 method to initialize the OpenACC library and allocate the appropriate 2668 hardware resources. Other methods are available through the use of 2669 environment variables and these will be discussed in the next section. 2670 2671 Once the call to 'acc_set_device_num()' has completed, other OpenACC 2672 functions can be called as seen with multiple calls being made to 2673 'acc_copyin()'. In addition, calls can be made to functions in the 2674 CUBLAS library. In the use case a call to 'cublasCreate()' is made 2675 subsequent to the calls to 'acc_copyin()'. As seen in the previous use 2676 case, a call to 'cublasCreate()' initializes the CUBLAS library and 2677 allocates the hardware resources on the host and the device. However, 2678 since the device has already been allocated, 'cublasCreate()' will only 2679 initialize the CUBLAS library and allocate the appropriate hardware 2680 resources on the host. The context that was created as part of the 2681 OpenACC initialization is shared with the CUBLAS library, similarly to 2682 the first use case. 2683 2684 dev = 0; 2685 2686 acc_set_device_num(dev, acc_device_nvidia); 2687 2688 /* Copy the first set to the device */ 2689 d_X = acc_copyin(&h_X[0], N * sizeof (float)); 2690 if (d_X == NULL) 2691 { 2692 fprintf(stderr, "copyin error h_X\n"); 2693 exit(EXIT_FAILURE); 2694 } 2695 2696 /* Copy the second set to the device */ 2697 d_Y = acc_copyin(&h_Y1[0], N * sizeof (float)); 2698 if (d_Y == NULL) 2699 { 2700 fprintf(stderr, "copyin error h_Y1\n"); 2701 exit(EXIT_FAILURE); 2702 } 2703 2704 /* Create the handle */ 2705 s = cublasCreate(&h); 2706 if (s != CUBLAS_STATUS_SUCCESS) 2707 { 2708 fprintf(stderr, "cublasCreate failed %d\n", s); 2709 exit(EXIT_FAILURE); 2710 } 2711 2712 /* Perform saxpy using CUBLAS library function */ 2713 s = cublasSaxpy(h, N, &alpha, d_X, 1, d_Y, 1); 2714 if (s != CUBLAS_STATUS_SUCCESS) 2715 { 2716 fprintf(stderr, "cublasSaxpy failed %d\n", s); 2717 exit(EXIT_FAILURE); 2718 } 2719 2720 /* Copy the results from the device */ 2721 acc_memcpy_from_device(&h_Y1[0], d_Y, N * sizeof (float)); 2722 2723 Use Case 2 2724 2725 8.4 OpenACC library and environment variables 2726 ============================================= 2727 2728 There are two environment variables associated with the OpenACC library 2729 that may be used to control the device type and device number: 2730 'ACC_DEVICE_TYPE' and 'ACC_DEVICE_NUM', respecively. These two 2731 environement variables can be used as an alternative to calling 2732 'acc_set_device_num()'. As seen in the second use case, the device type 2733 and device number were specified using 'acc_set_device_num()'. If 2734 however, the aforementioned environment variables were set, then the 2735 call to 'acc_set_device_num()' would not be required. 2736 2737 The use of the environment variables is only relevant when an OpenACC 2738 function is called prior to a call to 'cudaCreate()'. If 'cudaCreate()' 2739 is called prior to a call to an OpenACC function, then you must call 2740 'acc_set_device_num()'(2) 2741 2742 ---------- Footnotes ---------- 2743 2744 (1) See section 2.26, "Interactions with the CUDA Driver API" in 2745 "CUDA Runtime API", Version 5.5, and section 2.27, "VDPAU 2746 Interoperability", in "CUDA Driver API", TRM-06703-001, Version 5.5, for 2747 additional information on library interoperability. 2748 2749 (2) More complete information about 'ACC_DEVICE_TYPE' and 2750 'ACC_DEVICE_NUM' can be found in sections 4.1 and 4.2 of the OpenACC 2751 (http://www.openacc.org/) Application Programming Interface, Version 2752 2.0. 2753 2754 2755 File: libgomp.info, Node: The libgomp ABI, Next: Reporting Bugs, Prev: OpenACC Library Interoperability, Up: Top 2756 2757 9 The libgomp ABI 2758 ***************** 2759 2760 The following sections present notes on the external ABI as presented by 2761 libgomp. Only maintainers should need them. 2762 2763 * Menu: 2764 2765 * Implementing MASTER construct:: 2766 * Implementing CRITICAL construct:: 2767 * Implementing ATOMIC construct:: 2768 * Implementing FLUSH construct:: 2769 * Implementing BARRIER construct:: 2770 * Implementing THREADPRIVATE construct:: 2771 * Implementing PRIVATE clause:: 2772 * Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses:: 2773 * Implementing REDUCTION clause:: 2774 * Implementing PARALLEL construct:: 2775 * Implementing FOR construct:: 2776 * Implementing ORDERED construct:: 2777 * Implementing SECTIONS construct:: 2778 * Implementing SINGLE construct:: 2779 * Implementing OpenACC's PARALLEL construct:: 2780 2781 2782 File: libgomp.info, Node: Implementing MASTER construct, Next: Implementing CRITICAL construct, Up: The libgomp ABI 2783 2784 9.1 Implementing MASTER construct 2785 ================================= 2786 2787 if (omp_get_thread_num () == 0) 2788 block 2789 2790 Alternately, we generate two copies of the parallel subfunction and 2791 only include this in the version run by the master thread. Surely this 2792 is not worthwhile though... 2793 2794 2795 File: libgomp.info, Node: Implementing CRITICAL construct, Next: Implementing ATOMIC construct, Prev: Implementing MASTER construct, Up: The libgomp ABI 2796 2797 9.2 Implementing CRITICAL construct 2798 =================================== 2799 2800 Without a specified name, 2801 2802 void GOMP_critical_start (void); 2803 void GOMP_critical_end (void); 2804 2805 so that we don't get COPY relocations from libgomp to the main 2806 application. 2807 2808 With a specified name, use omp_set_lock and omp_unset_lock with name 2809 being transformed into a variable declared like 2810 2811 omp_lock_t gomp_critical_user_<name> __attribute__((common)) 2812 2813 Ideally the ABI would specify that all zero is a valid unlocked 2814 state, and so we wouldn't need to initialize this at startup. 2815 2816 2817 File: libgomp.info, Node: Implementing ATOMIC construct, Next: Implementing FLUSH construct, Prev: Implementing CRITICAL construct, Up: The libgomp ABI 2818 2819 9.3 Implementing ATOMIC construct 2820 ================================= 2821 2822 The target should implement the '__sync' builtins. 2823 2824 Failing that we could add 2825 2826 void GOMP_atomic_enter (void) 2827 void GOMP_atomic_exit (void) 2828 2829 which reuses the regular lock code, but with yet another lock object 2830 private to the library. 2831 2832 2833 File: libgomp.info, Node: Implementing FLUSH construct, Next: Implementing BARRIER construct, Prev: Implementing ATOMIC construct, Up: The libgomp ABI 2834 2835 9.4 Implementing FLUSH construct 2836 ================================ 2837 2838 Expands to the '__sync_synchronize' builtin. 2839 2840 2841 File: libgomp.info, Node: Implementing BARRIER construct, Next: Implementing THREADPRIVATE construct, Prev: Implementing FLUSH construct, Up: The libgomp ABI 2842 2843 9.5 Implementing BARRIER construct 2844 ================================== 2845 2846 void GOMP_barrier (void) 2847 2848 2849 File: libgomp.info, Node: Implementing THREADPRIVATE construct, Next: Implementing PRIVATE clause, Prev: Implementing BARRIER construct, Up: The libgomp ABI 2850 2851 9.6 Implementing THREADPRIVATE construct 2852 ======================================== 2853 2854 In _most_ cases we can map this directly to '__thread'. Except that OMP 2855 allows constructors for C++ objects. We can either refuse to support 2856 this (how often is it used?) or we can implement something akin to 2857 .ctors. 2858 2859 Even more ideally, this ctor feature is handled by extensions to the 2860 main pthreads library. Failing that, we can have a set of entry points 2861 to register ctor functions to be called. 2862 2863 2864 File: libgomp.info, Node: Implementing PRIVATE clause, Next: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Prev: Implementing THREADPRIVATE construct, Up: The libgomp ABI 2865 2866 9.7 Implementing PRIVATE clause 2867 =============================== 2868 2869 In association with a PARALLEL, or within the lexical extent of a 2870 PARALLEL block, the variable becomes a local variable in the parallel 2871 subfunction. 2872 2873 In association with FOR or SECTIONS blocks, create a new automatic 2874 variable within the current function. This preserves the semantic of 2875 new variable creation. 2876 2877 2878 File: libgomp.info, Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Next: Implementing REDUCTION clause, Prev: Implementing PRIVATE clause, Up: The libgomp ABI 2879 2880 9.8 Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses 2881 ======================================================================== 2882 2883 This seems simple enough for PARALLEL blocks. Create a private struct 2884 for communicating between the parent and subfunction. In the parent, 2885 copy in values for scalar and "small" structs; copy in addresses for 2886 others TREE_ADDRESSABLE types. In the subfunction, copy the value into 2887 the local variable. 2888 2889 It is not clear what to do with bare FOR or SECTION blocks. The only 2890 thing I can figure is that we do something like: 2891 2892 #pragma omp for firstprivate(x) lastprivate(y) 2893 for (int i = 0; i < n; ++i) 2894 body; 2895 2896 which becomes 2897 2898 { 2899 int x = x, y; 2900 2901 // for stuff 2902 2903 if (i == n) 2904 y = y; 2905 } 2906 2907 where the "x=x" and "y=y" assignments actually have different uids 2908 for the two variables, i.e. not something you could write directly in 2909 C. Presumably this only makes sense if the "outer" x and y are global 2910 variables. 2911 2912 COPYPRIVATE would work the same way, except the structure broadcast 2913 would have to happen via SINGLE machinery instead. 2914 2915 2916 File: libgomp.info, Node: Implementing REDUCTION clause, Next: Implementing PARALLEL construct, Prev: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses, Up: The libgomp ABI 2917 2918 9.9 Implementing REDUCTION clause 2919 ================================= 2920 2921 The private struct mentioned in the previous section should have a 2922 pointer to an array of the type of the variable, indexed by the thread's 2923 TEAM_ID. The thread stores its final value into the array, and after 2924 the barrier, the master thread iterates over the array to collect the 2925 values. 2926 2927 2928 File: libgomp.info, Node: Implementing PARALLEL construct, Next: Implementing FOR construct, Prev: Implementing REDUCTION clause, Up: The libgomp ABI 2929 2930 9.10 Implementing PARALLEL construct 2931 ==================================== 2932 2933 #pragma omp parallel 2934 { 2935 body; 2936 } 2937 2938 becomes 2939 2940 void subfunction (void *data) 2941 { 2942 use data; 2943 body; 2944 } 2945 2946 setup data; 2947 GOMP_parallel_start (subfunction, &data, num_threads); 2948 subfunction (&data); 2949 GOMP_parallel_end (); 2950 2951 void GOMP_parallel_start (void (*fn)(void *), void *data, unsigned num_threads) 2952 2953 The FN argument is the subfunction to be run in parallel. 2954 2955 The DATA argument is a pointer to a structure used to communicate 2956 data in and out of the subfunction, as discussed above with respect to 2957 FIRSTPRIVATE et al. 2958 2959 The NUM_THREADS argument is 1 if an IF clause is present and false, 2960 or the value of the NUM_THREADS clause, if present, or 0. 2961 2962 The function needs to create the appropriate number of threads and/or 2963 launch them from the dock. It needs to create the team structure and 2964 assign team ids. 2965 2966 void GOMP_parallel_end (void) 2967 2968 Tears down the team and returns us to the previous 2969 'omp_in_parallel()' state. 2970 2971 2972 File: libgomp.info, Node: Implementing FOR construct, Next: Implementing ORDERED construct, Prev: Implementing PARALLEL construct, Up: The libgomp ABI 2973 2974 9.11 Implementing FOR construct 2975 =============================== 2976 2977 #pragma omp parallel for 2978 for (i = lb; i <= ub; i++) 2979 body; 2980 2981 becomes 2982 2983 void subfunction (void *data) 2984 { 2985 long _s0, _e0; 2986 while (GOMP_loop_static_next (&_s0, &_e0)) 2987 { 2988 long _e1 = _e0, i; 2989 for (i = _s0; i < _e1; i++) 2990 body; 2991 } 2992 GOMP_loop_end_nowait (); 2993 } 2994 2995 GOMP_parallel_loop_static (subfunction, NULL, 0, lb, ub+1, 1, 0); 2996 subfunction (NULL); 2997 GOMP_parallel_end (); 2998 2999 #pragma omp for schedule(runtime) 3000 for (i = 0; i < n; i++) 3001 body; 3002 3003 becomes 3004 3005 { 3006 long i, _s0, _e0; 3007 if (GOMP_loop_runtime_start (0, n, 1, &_s0, &_e0)) 3008 do { 3009 long _e1 = _e0; 3010 for (i = _s0, i < _e0; i++) 3011 body; 3012 } while (GOMP_loop_runtime_next (&_s0, _&e0)); 3013 GOMP_loop_end (); 3014 } 3015 3016 Note that while it looks like there is trickiness to propagating a 3017 non-constant STEP, there isn't really. We're explicitly allowed to 3018 evaluate it as many times as we want, and any variables involved should 3019 automatically be handled as PRIVATE or SHARED like any other variables. 3020 So the expression should remain evaluable in the subfunction. We can 3021 also pull it into a local variable if we like, but since its supposed to 3022 remain unchanged, we can also not if we like. 3023 3024 If we have SCHEDULE(STATIC), and no ORDERED, then we ought to be able 3025 to get away with no work-sharing context at all, since we can simply 3026 perform the arithmetic directly in each thread to divide up the 3027 iterations. Which would mean that we wouldn't need to call any of these 3028 routines. 3029 3030 There are separate routines for handling loops with an ORDERED 3031 clause. Bookkeeping for that is non-trivial... 3032 3033 3034 File: libgomp.info, Node: Implementing ORDERED construct, Next: Implementing SECTIONS construct, Prev: Implementing FOR construct, Up: The libgomp ABI 3035 3036 9.12 Implementing ORDERED construct 3037 =================================== 3038 3039 void GOMP_ordered_start (void) 3040 void GOMP_ordered_end (void) 3041 3042 3043 File: libgomp.info, Node: Implementing SECTIONS construct, Next: Implementing SINGLE construct, Prev: Implementing ORDERED construct, Up: The libgomp ABI 3044 3045 9.13 Implementing SECTIONS construct 3046 ==================================== 3047 3048 A block as 3049 3050 #pragma omp sections 3051 { 3052 #pragma omp section 3053 stmt1; 3054 #pragma omp section 3055 stmt2; 3056 #pragma omp section 3057 stmt3; 3058 } 3059 3060 becomes 3061 3062 for (i = GOMP_sections_start (3); i != 0; i = GOMP_sections_next ()) 3063 switch (i) 3064 { 3065 case 1: 3066 stmt1; 3067 break; 3068 case 2: 3069 stmt2; 3070 break; 3071 case 3: 3072 stmt3; 3073 break; 3074 } 3075 GOMP_barrier (); 3076 3077 3078 File: libgomp.info, Node: Implementing SINGLE construct, Next: Implementing OpenACC's PARALLEL construct, Prev: Implementing SECTIONS construct, Up: The libgomp ABI 3079 3080 9.14 Implementing SINGLE construct 3081 ================================== 3082 3083 A block like 3084 3085 #pragma omp single 3086 { 3087 body; 3088 } 3089 3090 becomes 3091 3092 if (GOMP_single_start ()) 3093 body; 3094 GOMP_barrier (); 3095 3096 while 3097 3098 #pragma omp single copyprivate(x) 3099 body; 3100 3101 becomes 3102 3103 datap = GOMP_single_copy_start (); 3104 if (datap == NULL) 3105 { 3106 body; 3107 data.x = x; 3108 GOMP_single_copy_end (&data); 3109 } 3110 else 3111 x = datap->x; 3112 GOMP_barrier (); 3113 3114 3115 File: libgomp.info, Node: Implementing OpenACC's PARALLEL construct, Prev: Implementing SINGLE construct, Up: The libgomp ABI 3116 3117 9.15 Implementing OpenACC's PARALLEL construct 3118 ============================================== 3119 3120 void GOACC_parallel () 3121 3122 3123 File: libgomp.info, Node: Reporting Bugs, Next: Copying, Prev: The libgomp ABI, Up: Top 3124 3125 10 Reporting Bugs 3126 ***************** 3127 3128 Bugs in the GNU Offloading and Multi Processing Runtime Library should 3129 be reported via Bugzilla (http://gcc.gnu.org/bugzilla/). Please add 3130 "openacc", or "openmp", or both to the keywords field in the bug report, 3131 as appropriate. 3132 3133 3134 File: libgomp.info, Node: Copying, Next: GNU Free Documentation License, Prev: Reporting Bugs, Up: Top 3135 3136 GNU General Public License 3137 ************************** 3138 3139 Version 3, 29 June 2007 3140 3141 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/> 3142 3143 Everyone is permitted to copy and distribute verbatim copies of this 3144 license document, but changing it is not allowed. 3145 3146 Preamble 3147 ======== 3148 3149 The GNU General Public License is a free, copyleft license for software 3150 and other kinds of works. 3151 3152 The licenses for most software and other practical works are designed 3153 to take away your freedom to share and change the works. By contrast, 3154 the GNU General Public License is intended to guarantee your freedom to 3155 share and change all versions of a program-to make sure it remains free 3156 software for all its users. We, the Free Software Foundation, use the 3157 GNU General Public License for most of our software; it applies also to 3158 any other work released this way by its authors. You can apply it to 3159 your programs, too. 3160 3161 When we speak of free software, we are referring to freedom, not 3162 price. Our General Public Licenses are designed to make sure that you 3163 have the freedom to distribute copies of free software (and charge for 3164 them if you wish), that you receive source code or can get it if you 3165 want it, that you can change the software or use pieces of it in new 3166 free programs, and that you know you can do these things. 3167 3168 To protect your rights, we need to prevent others from denying you 3169 these rights or asking you to surrender the rights. Therefore, you have 3170 certain responsibilities if you distribute copies of the software, or if 3171 you modify it: responsibilities to respect the freedom of others. 3172 3173 For example, if you distribute copies of such a program, whether 3174 gratis or for a fee, you must pass on to the recipients the same 3175 freedoms that you received. You must make sure that they, too, receive 3176 or can get the source code. And you must show them these terms so they 3177 know their rights. 3178 3179 Developers that use the GNU GPL protect your rights with two steps: 3180 (1) assert copyright on the software, and (2) offer you this License 3181 giving you legal permission to copy, distribute and/or modify it. 3182 3183 For the developers' and authors' protection, the GPL clearly explains 3184 that there is no warranty for this free software. For both users' and 3185 authors' sake, the GPL requires that modified versions be marked as 3186 changed, so that their problems will not be attributed erroneously to 3187 authors of previous versions. 3188 3189 Some devices are designed to deny users access to install or run 3190 modified versions of the software inside them, although the manufacturer 3191 can do so. This is fundamentally incompatible with the aim of 3192 protecting users' freedom to change the software. The systematic 3193 pattern of such abuse occurs in the area of products for individuals to 3194 use, which is precisely where it is most unacceptable. Therefore, we 3195 have designed this version of the GPL to prohibit the practice for those 3196 products. If such problems arise substantially in other domains, we 3197 stand ready to extend this provision to those domains in future versions 3198 of the GPL, as needed to protect the freedom of users. 3199 3200 Finally, every program is threatened constantly by software patents. 3201 States should not allow patents to restrict development and use of 3202 software on general-purpose computers, but in those that do, we wish to 3203 avoid the special danger that patents applied to a free program could 3204 make it effectively proprietary. To prevent this, the GPL assures that 3205 patents cannot be used to render the program non-free. 3206 3207 The precise terms and conditions for copying, distribution and 3208 modification follow. 3209 3210 TERMS AND CONDITIONS 3211 ==================== 3212 3213 0. Definitions. 3214 3215 "This License" refers to version 3 of the GNU General Public 3216 License. 3217 3218 "Copyright" also means copyright-like laws that apply to other 3219 kinds of works, such as semiconductor masks. 3220 3221 "The Program" refers to any copyrightable work licensed under this 3222 License. Each licensee is addressed as "you". "Licensees" and 3223 "recipients" may be individuals or organizations. 3224 3225 To "modify" a work means to copy from or adapt all or part of the 3226 work in a fashion requiring copyright permission, other than the 3227 making of an exact copy. The resulting work is called a "modified 3228 version" of the earlier work or a work "based on" the earlier work. 3229 3230 A "covered work" means either the unmodified Program or a work 3231 based on the Program. 3232 3233 To "propagate" a work means to do anything with it that, without 3234 permission, would make you directly or secondarily liable for 3235 infringement under applicable copyright law, except executing it on 3236 a computer or modifying a private copy. Propagation includes 3237 copying, distribution (with or without modification), making 3238 available to the public, and in some countries other activities as 3239 well. 3240 3241 To "convey" a work means any kind of propagation that enables other 3242 parties to make or receive copies. Mere interaction with a user 3243 through a computer network, with no transfer of a copy, is not 3244 conveying. 3245 3246 An interactive user interface displays "Appropriate Legal Notices" 3247 to the extent that it includes a convenient and prominently visible 3248 feature that (1) displays an appropriate copyright notice, and (2) 3249 tells the user that there is no warranty for the work (except to 3250 the extent that warranties are provided), that licensees may convey 3251 the work under this License, and how to view a copy of this 3252 License. If the interface presents a list of user commands or 3253 options, such as a menu, a prominent item in the list meets this 3254 criterion. 3255 3256 1. Source Code. 3257 3258 The "source code" for a work means the preferred form of the work 3259 for making modifications to it. "Object code" means any non-source 3260 form of a work. 3261 3262 A "Standard Interface" means an interface that either is an 3263 official standard defined by a recognized standards body, or, in 3264 the case of interfaces specified for a particular programming 3265 language, one that is widely used among developers working in that 3266 language. 3267 3268 The "System Libraries" of an executable work include anything, 3269 other than the work as a whole, that (a) is included in the normal 3270 form of packaging a Major Component, but which is not part of that 3271 Major Component, and (b) serves only to enable use of the work with 3272 that Major Component, or to implement a Standard Interface for 3273 which an implementation is available to the public in source code 3274 form. A "Major Component", in this context, means a major 3275 essential component (kernel, window system, and so on) of the 3276 specific operating system (if any) on which the executable work 3277 runs, or a compiler used to produce the work, or an object code 3278 interpreter used to run it. 3279 3280 The "Corresponding Source" for a work in object code form means all 3281 the source code needed to generate, install, and (for an executable 3282 work) run the object code and to modify the work, including scripts 3283 to control those activities. However, it does not include the 3284 work's System Libraries, or general-purpose tools or generally 3285 available free programs which are used unmodified in performing 3286 those activities but which are not part of the work. For example, 3287 Corresponding Source includes interface definition files associated 3288 with source files for the work, and the source code for shared 3289 libraries and dynamically linked subprograms that the work is 3290 specifically designed to require, such as by intimate data 3291 communication or control flow between those subprograms and other 3292 parts of the work. 3293 3294 The Corresponding Source need not include anything that users can 3295 regenerate automatically from other parts of the Corresponding 3296 Source. 3297 3298 The Corresponding Source for a work in source code form is that 3299 same work. 3300 3301 2. Basic Permissions. 3302 3303 All rights granted under this License are granted for the term of 3304 copyright on the Program, and are irrevocable provided the stated 3305 conditions are met. This License explicitly affirms your unlimited 3306 permission to run the unmodified Program. The output from running 3307 a covered work is covered by this License only if the output, given 3308 its content, constitutes a covered work. This License acknowledges 3309 your rights of fair use or other equivalent, as provided by 3310 copyright law. 3311 3312 You may make, run and propagate covered works that you do not 3313 convey, without conditions so long as your license otherwise 3314 remains in force. You may convey covered works to others for the 3315 sole purpose of having them make modifications exclusively for you, 3316 or provide you with facilities for running those works, provided 3317 that you comply with the terms of this License in conveying all 3318 material for which you do not control copyright. Those thus making 3319 or running the covered works for you must do so exclusively on your 3320 behalf, under your direction and control, on terms that prohibit 3321 them from making any copies of your copyrighted material outside 3322 their relationship with you. 3323 3324 Conveying under any other circumstances is permitted solely under 3325 the conditions stated below. Sublicensing is not allowed; section 3326 10 makes it unnecessary. 3327 3328 3. Protecting Users' Legal Rights From Anti-Circumvention Law. 3329 3330 No covered work shall be deemed part of an effective technological 3331 measure under any applicable law fulfilling obligations under 3332 article 11 of the WIPO copyright treaty adopted on 20 December 3333 1996, or similar laws prohibiting or restricting circumvention of 3334 such measures. 3335 3336 When you convey a covered work, you waive any legal power to forbid 3337 circumvention of technological measures to the extent such 3338 circumvention is effected by exercising rights under this License 3339 with respect to the covered work, and you disclaim any intention to 3340 limit operation or modification of the work as a means of 3341 enforcing, against the work's users, your or third parties' legal 3342 rights to forbid circumvention of technological measures. 3343 3344 4. Conveying Verbatim Copies. 3345 3346 You may convey verbatim copies of the Program's source code as you 3347 receive it, in any medium, provided that you conspicuously and 3348 appropriately publish on each copy an appropriate copyright notice; 3349 keep intact all notices stating that this License and any 3350 non-permissive terms added in accord with section 7 apply to the 3351 code; keep intact all notices of the absence of any warranty; and 3352 give all recipients a copy of this License along with the Program. 3353 3354 You may charge any price or no price for each copy that you convey, 3355 and you may offer support or warranty protection for a fee. 3356 3357 5. Conveying Modified Source Versions. 3358 3359 You may convey a work based on the Program, or the modifications to 3360 produce it from the Program, in the form of source code under the 3361 terms of section 4, provided that you also meet all of these 3362 conditions: 3363 3364 a. The work must carry prominent notices stating that you 3365 modified it, and giving a relevant date. 3366 3367 b. The work must carry prominent notices stating that it is 3368 released under this License and any conditions added under 3369 section 7. This requirement modifies the requirement in 3370 section 4 to "keep intact all notices". 3371 3372 c. You must license the entire work, as a whole, under this 3373 License to anyone who comes into possession of a copy. This 3374 License will therefore apply, along with any applicable 3375 section 7 additional terms, to the whole of the work, and all 3376 its parts, regardless of how they are packaged. This License 3377 gives no permission to license the work in any other way, but 3378 it does not invalidate such permission if you have separately 3379 received it. 3380 3381 d. If the work has interactive user interfaces, each must display 3382 Appropriate Legal Notices; however, if the Program has 3383 interactive interfaces that do not display Appropriate Legal 3384 Notices, your work need not make them do so. 3385 3386 A compilation of a covered work with other separate and independent 3387 works, which are not by their nature extensions of the covered 3388 work, and which are not combined with it such as to form a larger 3389 program, in or on a volume of a storage or distribution medium, is 3390 called an "aggregate" if the compilation and its resulting 3391 copyright are not used to limit the access or legal rights of the 3392 compilation's users beyond what the individual works permit. 3393 Inclusion of a covered work in an aggregate does not cause this 3394 License to apply to the other parts of the aggregate. 3395 3396 6. Conveying Non-Source Forms. 3397 3398 You may convey a covered work in object code form under the terms 3399 of sections 4 and 5, provided that you also convey the 3400 machine-readable Corresponding Source under the terms of this 3401 License, in one of these ways: 3402 3403 a. Convey the object code in, or embodied in, a physical product 3404 (including a physical distribution medium), accompanied by the 3405 Corresponding Source fixed on a durable physical medium 3406 customarily used for software interchange. 3407 3408 b. Convey the object code in, or embodied in, a physical product 3409 (including a physical distribution medium), accompanied by a 3410 written offer, valid for at least three years and valid for as 3411 long as you offer spare parts or customer support for that 3412 product model, to give anyone who possesses the object code 3413 either (1) a copy of the Corresponding Source for all the 3414 software in the product that is covered by this License, on a 3415 durable physical medium customarily used for software 3416 interchange, for a price no more than your reasonable cost of 3417 physically performing this conveying of source, or (2) access 3418 to copy the Corresponding Source from a network server at no 3419 charge. 3420 3421 c. Convey individual copies of the object code with a copy of the 3422 written offer to provide the Corresponding Source. This 3423 alternative is allowed only occasionally and noncommercially, 3424 and only if you received the object code with such an offer, 3425 in accord with subsection 6b. 3426 3427 d. Convey the object code by offering access from a designated 3428 place (gratis or for a charge), and offer equivalent access to 3429 the Corresponding Source in the same way through the same 3430 place at no further charge. You need not require recipients 3431 to copy the Corresponding Source along with the object code. 3432 If the place to copy the object code is a network server, the 3433 Corresponding Source may be on a different server (operated by 3434 you or a third party) that supports equivalent copying 3435 facilities, provided you maintain clear directions next to the 3436 object code saying where to find the Corresponding Source. 3437 Regardless of what server hosts the Corresponding Source, you 3438 remain obligated to ensure that it is available for as long as 3439 needed to satisfy these requirements. 3440 3441 e. Convey the object code using peer-to-peer transmission, 3442 provided you inform other peers where the object code and 3443 Corresponding Source of the work are being offered to the 3444 general public at no charge under subsection 6d. 3445 3446 A separable portion of the object code, whose source code is 3447 excluded from the Corresponding Source as a System Library, need 3448 not be included in conveying the object code work. 3449 3450 A "User Product" is either (1) a "consumer product", which means 3451 any tangible personal property which is normally used for personal, 3452 family, or household purposes, or (2) anything designed or sold for 3453 incorporation into a dwelling. In determining whether a product is 3454 a consumer product, doubtful cases shall be resolved in favor of 3455 coverage. For a particular product received by a particular user, 3456 "normally used" refers to a typical or common use of that class of 3457 product, regardless of the status of the particular user or of the 3458 way in which the particular user actually uses, or expects or is 3459 expected to use, the product. A product is a consumer product 3460 regardless of whether the product has substantial commercial, 3461 industrial or non-consumer uses, unless such uses represent the 3462 only significant mode of use of the product. 3463 3464 "Installation Information" for a User Product means any methods, 3465 procedures, authorization keys, or other information required to 3466 install and execute modified versions of a covered work in that 3467 User Product from a modified version of its Corresponding Source. 3468 The information must suffice to ensure that the continued 3469 functioning of the modified object code is in no case prevented or 3470 interfered with solely because modification has been made. 3471 3472 If you convey an object code work under this section in, or with, 3473 or specifically for use in, a User Product, and the conveying 3474 occurs as part of a transaction in which the right of possession 3475 and use of the User Product is transferred to the recipient in 3476 perpetuity or for a fixed term (regardless of how the transaction 3477 is characterized), the Corresponding Source conveyed under this 3478 section must be accompanied by the Installation Information. But 3479 this requirement does not apply if neither you nor any third party 3480 retains the ability to install modified object code on the User 3481 Product (for example, the work has been installed in ROM). 3482 3483 The requirement to provide Installation Information does not 3484 include a requirement to continue to provide support service, 3485 warranty, or updates for a work that has been modified or installed 3486 by the recipient, or for the User Product in which it has been 3487 modified or installed. Access to a network may be denied when the 3488 modification itself materially and adversely affects the operation 3489 of the network or violates the rules and protocols for 3490 communication across the network. 3491 3492 Corresponding Source conveyed, and Installation Information 3493 provided, in accord with this section must be in a format that is 3494 publicly documented (and with an implementation available to the 3495 public in source code form), and must require no special password 3496 or key for unpacking, reading or copying. 3497 3498 7. Additional Terms. 3499 3500 "Additional permissions" are terms that supplement the terms of 3501 this License by making exceptions from one or more of its 3502 conditions. Additional permissions that are applicable to the 3503 entire Program shall be treated as though they were included in 3504 this License, to the extent that they are valid under applicable 3505 law. If additional permissions apply only to part of the Program, 3506 that part may be used separately under those permissions, but the 3507 entire Program remains governed by this License without regard to 3508 the additional permissions. 3509 3510 When you convey a copy of a covered work, you may at your option 3511 remove any additional permissions from that copy, or from any part 3512 of it. (Additional permissions may be written to require their own 3513 removal in certain cases when you modify the work.) You may place 3514 additional permissions on material, added by you to a covered work, 3515 for which you have or can give appropriate copyright permission. 3516 3517 Notwithstanding any other provision of this License, for material 3518 you add to a covered work, you may (if authorized by the copyright 3519 holders of that material) supplement the terms of this License with 3520 terms: 3521 3522 a. Disclaiming warranty or limiting liability differently from 3523 the terms of sections 15 and 16 of this License; or 3524 3525 b. Requiring preservation of specified reasonable legal notices 3526 or author attributions in that material or in the Appropriate 3527 Legal Notices displayed by works containing it; or 3528 3529 c. Prohibiting misrepresentation of the origin of that material, 3530 or requiring that modified versions of such material be marked 3531 in reasonable ways as different from the original version; or 3532 3533 d. Limiting the use for publicity purposes of names of licensors 3534 or authors of the material; or 3535 3536 e. Declining to grant rights under trademark law for use of some 3537 trade names, trademarks, or service marks; or 3538 3539 f. Requiring indemnification of licensors and authors of that 3540 material by anyone who conveys the material (or modified 3541 versions of it) with contractual assumptions of liability to 3542 the recipient, for any liability that these contractual 3543 assumptions directly impose on those licensors and authors. 3544 3545 All other non-permissive additional terms are considered "further 3546 restrictions" within the meaning of section 10. If the Program as 3547 you received it, or any part of it, contains a notice stating that 3548 it is governed by this License along with a term that is a further 3549 restriction, you may remove that term. If a license document 3550 contains a further restriction but permits relicensing or conveying 3551 under this License, you may add to a covered work material governed 3552 by the terms of that license document, provided that the further 3553 restriction does not survive such relicensing or conveying. 3554 3555 If you add terms to a covered work in accord with this section, you 3556 must place, in the relevant source files, a statement of the 3557 additional terms that apply to those files, or a notice indicating 3558 where to find the applicable terms. 3559 3560 Additional terms, permissive or non-permissive, may be stated in 3561 the form of a separately written license, or stated as exceptions; 3562 the above requirements apply either way. 3563 3564 8. Termination. 3565 3566 You may not propagate or modify a covered work except as expressly 3567 provided under this License. Any attempt otherwise to propagate or 3568 modify it is void, and will automatically terminate your rights 3569 under this License (including any patent licenses granted under the 3570 third paragraph of section 11). 3571 3572 However, if you cease all violation of this License, then your 3573 license from a particular copyright holder is reinstated (a) 3574 provisionally, unless and until the copyright holder explicitly and 3575 finally terminates your license, and (b) permanently, if the 3576 copyright holder fails to notify you of the violation by some 3577 reasonable means prior to 60 days after the cessation. 3578 3579 Moreover, your license from a particular copyright holder is 3580 reinstated permanently if the copyright holder notifies you of the 3581 violation by some reasonable means, this is the first time you have 3582 received notice of violation of this License (for any work) from 3583 that copyright holder, and you cure the violation prior to 30 days 3584 after your receipt of the notice. 3585 3586 Termination of your rights under this section does not terminate 3587 the licenses of parties who have received copies or rights from you 3588 under this License. If your rights have been terminated and not 3589 permanently reinstated, you do not qualify to receive new licenses 3590 for the same material under section 10. 3591 3592 9. Acceptance Not Required for Having Copies. 3593 3594 You are not required to accept this License in order to receive or 3595 run a copy of the Program. Ancillary propagation of a covered work 3596 occurring solely as a consequence of using peer-to-peer 3597 transmission to receive a copy likewise does not require 3598 acceptance. However, nothing other than this License grants you 3599 permission to propagate or modify any covered work. These actions 3600 infringe copyright if you do not accept this License. Therefore, 3601 by modifying or propagating a covered work, you indicate your 3602 acceptance of this License to do so. 3603 3604 10. Automatic Licensing of Downstream Recipients. 3605 3606 Each time you convey a covered work, the recipient automatically 3607 receives a license from the original licensors, to run, modify and 3608 propagate that work, subject to this License. You are not 3609 responsible for enforcing compliance by third parties with this 3610 License. 3611 3612 An "entity transaction" is a transaction transferring control of an 3613 organization, or substantially all assets of one, or subdividing an 3614 organization, or merging organizations. If propagation of a 3615 covered work results from an entity transaction, each party to that 3616 transaction who receives a copy of the work also receives whatever 3617 licenses to the work the party's predecessor in interest had or 3618 could give under the previous paragraph, plus a right to possession 3619 of the Corresponding Source of the work from the predecessor in 3620 interest, if the predecessor has it or can get it with reasonable 3621 efforts. 3622 3623 You may not impose any further restrictions on the exercise of the 3624 rights granted or affirmed under this License. For example, you 3625 may not impose a license fee, royalty, or other charge for exercise 3626 of rights granted under this License, and you may not initiate 3627 litigation (including a cross-claim or counterclaim in a lawsuit) 3628 alleging that any patent claim is infringed by making, using, 3629 selling, offering for sale, or importing the Program or any portion 3630 of it. 3631 3632 11. Patents. 3633 3634 A "contributor" is a copyright holder who authorizes use under this 3635 License of the Program or a work on which the Program is based. 3636 The work thus licensed is called the contributor's "contributor 3637 version". 3638 3639 A contributor's "essential patent claims" are all patent claims 3640 owned or controlled by the contributor, whether already acquired or 3641 hereafter acquired, that would be infringed by some manner, 3642 permitted by this License, of making, using, or selling its 3643 contributor version, but do not include claims that would be 3644 infringed only as a consequence of further modification of the 3645 contributor version. For purposes of this definition, "control" 3646 includes the right to grant patent sublicenses in a manner 3647 consistent with the requirements of this License. 3648 3649 Each contributor grants you a non-exclusive, worldwide, 3650 royalty-free patent license under the contributor's essential 3651 patent claims, to make, use, sell, offer for sale, import and 3652 otherwise run, modify and propagate the contents of its contributor 3653 version. 3654 3655 In the following three paragraphs, a "patent license" is any 3656 express agreement or commitment, however denominated, not to 3657 enforce a patent (such as an express permission to practice a 3658 patent or covenant not to sue for patent infringement). To "grant" 3659 such a patent license to a party means to make such an agreement or 3660 commitment not to enforce a patent against the party. 3661 3662 If you convey a covered work, knowingly relying on a patent 3663 license, and the Corresponding Source of the work is not available 3664 for anyone to copy, free of charge and under the terms of this 3665 License, through a publicly available network server or other 3666 readily accessible means, then you must either (1) cause the 3667 Corresponding Source to be so available, or (2) arrange to deprive 3668 yourself of the benefit of the patent license for this particular 3669 work, or (3) arrange, in a manner consistent with the requirements 3670 of this License, to extend the patent license to downstream 3671 recipients. "Knowingly relying" means you have actual knowledge 3672 that, but for the patent license, your conveying the covered work 3673 in a country, or your recipient's use of the covered work in a 3674 country, would infringe one or more identifiable patents in that 3675 country that you have reason to believe are valid. 3676 3677 If, pursuant to or in connection with a single transaction or 3678 arrangement, you convey, or propagate by procuring conveyance of, a 3679 covered work, and grant a patent license to some of the parties 3680 receiving the covered work authorizing them to use, propagate, 3681 modify or convey a specific copy of the covered work, then the 3682 patent license you grant is automatically extended to all 3683 recipients of the covered work and works based on it. 3684 3685 A patent license is "discriminatory" if it does not include within 3686 the scope of its coverage, prohibits the exercise of, or is 3687 conditioned on the non-exercise of one or more of the rights that 3688 are specifically granted under this License. You may not convey a 3689 covered work if you are a party to an arrangement with a third 3690 party that is in the business of distributing software, under which 3691 you make payment to the third party based on the extent of your 3692 activity of conveying the work, and under which the third party 3693 grants, to any of the parties who would receive the covered work 3694 from you, a discriminatory patent license (a) in connection with 3695 copies of the covered work conveyed by you (or copies made from 3696 those copies), or (b) primarily for and in connection with specific 3697 products or compilations that contain the covered work, unless you 3698 entered into that arrangement, or that patent license was granted, 3699 prior to 28 March 2007. 3700 3701 Nothing in this License shall be construed as excluding or limiting 3702 any implied license or other defenses to infringement that may 3703 otherwise be available to you under applicable patent law. 3704 3705 12. No Surrender of Others' Freedom. 3706 3707 If conditions are imposed on you (whether by court order, agreement 3708 or otherwise) that contradict the conditions of this License, they 3709 do not excuse you from the conditions of this License. If you 3710 cannot convey a covered work so as to satisfy simultaneously your 3711 obligations under this License and any other pertinent obligations, 3712 then as a consequence you may not convey it at all. For example, 3713 if you agree to terms that obligate you to collect a royalty for 3714 further conveying from those to whom you convey the Program, the 3715 only way you could satisfy both those terms and this License would 3716 be to refrain entirely from conveying the Program. 3717 3718 13. Use with the GNU Affero General Public License. 3719 3720 Notwithstanding any other provision of this License, you have 3721 permission to link or combine any covered work with a work licensed 3722 under version 3 of the GNU Affero General Public License into a 3723 single combined work, and to convey the resulting work. The terms 3724 of this License will continue to apply to the part which is the 3725 covered work, but the special requirements of the GNU Affero 3726 General Public License, section 13, concerning interaction through 3727 a network will apply to the combination as such. 3728 3729 14. Revised Versions of this License. 3730 3731 The Free Software Foundation may publish revised and/or new 3732 versions of the GNU General Public License from time to time. Such 3733 new versions will be similar in spirit to the present version, but 3734 may differ in detail to address new problems or concerns. 3735 3736 Each version is given a distinguishing version number. If the 3737 Program specifies that a certain numbered version of the GNU 3738 General Public License "or any later version" applies to it, you 3739 have the option of following the terms and conditions either of 3740 that numbered version or of any later version published by the Free 3741 Software Foundation. If the Program does not specify a version 3742 number of the GNU General Public License, you may choose any 3743 version ever published by the Free Software Foundation. 3744 3745 If the Program specifies that a proxy can decide which future 3746 versions of the GNU General Public License can be used, that 3747 proxy's public statement of acceptance of a version permanently 3748 authorizes you to choose that version for the Program. 3749 3750 Later license versions may give you additional or different 3751 permissions. However, no additional obligations are imposed on any 3752 author or copyright holder as a result of your choosing to follow a 3753 later version. 3754 3755 15. Disclaimer of Warranty. 3756 3757 THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 3758 APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE 3759 COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" 3760 WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, 3761 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 3762 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE 3763 RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. 3764 SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL 3765 NECESSARY SERVICING, REPAIR OR CORRECTION. 3766 3767 16. Limitation of Liability. 3768 3769 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN 3770 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES 3771 AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR 3772 DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR 3773 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE 3774 THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA 3775 BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 3776 PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 3777 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF 3778 THE POSSIBILITY OF SUCH DAMAGES. 3779 3780 17. Interpretation of Sections 15 and 16. 3781 3782 If the disclaimer of warranty and limitation of liability provided 3783 above cannot be given local legal effect according to their terms, 3784 reviewing courts shall apply local law that most closely 3785 approximates an absolute waiver of all civil liability in 3786 connection with the Program, unless a warranty or assumption of 3787 liability accompanies a copy of the Program in return for a fee. 3788 3789 END OF TERMS AND CONDITIONS 3790 =========================== 3791 3792 How to Apply These Terms to Your New Programs 3793 ============================================= 3794 3795 If you develop a new program, and you want it to be of the greatest 3796 possible use to the public, the best way to achieve this is to make it 3797 free software which everyone can redistribute and change under these 3798 terms. 3799 3800 To do so, attach the following notices to the program. It is safest 3801 to attach them to the start of each source file to most effectively 3802 state the exclusion of warranty; and each file should have at least the 3803 "copyright" line and a pointer to where the full notice is found. 3804 3805 ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES. 3806 Copyright (C) YEAR NAME OF AUTHOR 3807 3808 This program is free software: you can redistribute it and/or modify 3809 it under the terms of the GNU General Public License as published by 3810 the Free Software Foundation, either version 3 of the License, or (at 3811 your option) any later version. 3812 3813 This program is distributed in the hope that it will be useful, but 3814 WITHOUT ANY WARRANTY; without even the implied warranty of 3815 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 3816 General Public License for more details. 3817 3818 You should have received a copy of the GNU General Public License 3819 along with this program. If not, see <http://www.gnu.org/licenses/>. 3820 3821 Also add information on how to contact you by electronic and paper 3822 mail. 3823 3824 If the program does terminal interaction, make it output a short 3825 notice like this when it starts in an interactive mode: 3826 3827 PROGRAM Copyright (C) YEAR NAME OF AUTHOR 3828 This program comes with ABSOLUTELY NO WARRANTY; for details type 'show w'. 3829 This is free software, and you are welcome to redistribute it 3830 under certain conditions; type 'show c' for details. 3831 3832 The hypothetical commands 'show w' and 'show c' should show the 3833 appropriate parts of the General Public License. Of course, your 3834 program's commands might be different; for a GUI interface, you would 3835 use an "about box". 3836 3837 You should also get your employer (if you work as a programmer) or 3838 school, if any, to sign a "copyright disclaimer" for the program, if 3839 necessary. For more information on this, and how to apply and follow 3840 the GNU GPL, see <http://www.gnu.org/licenses/>. 3841 3842 The GNU General Public License does not permit incorporating your 3843 program into proprietary programs. If your program is a subroutine 3844 library, you may consider it more useful to permit linking proprietary 3845 applications with the library. If this is what you want to do, use the 3846 GNU Lesser General Public License instead of this License. But first, 3847 please read <http://www.gnu.org/philosophy/why-not-lgpl.html>. 3848 3849 3850 File: libgomp.info, Node: GNU Free Documentation License, Next: Funding, Prev: Copying, Up: Top 3851 3852 GNU Free Documentation License 3853 ****************************** 3854 3855 Version 1.3, 3 November 2008 3856 3857 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. 3858 <http://fsf.org/> 3859 3860 Everyone is permitted to copy and distribute verbatim copies 3861 of this license document, but changing it is not allowed. 3862 3863 0. PREAMBLE 3864 3865 The purpose of this License is to make a manual, textbook, or other 3866 functional and useful document "free" in the sense of freedom: to 3867 assure everyone the effective freedom to copy and redistribute it, 3868 with or without modifying it, either commercially or 3869 noncommercially. Secondarily, this License preserves for the 3870 author and publisher a way to get credit for their work, while not 3871 being considered responsible for modifications made by others. 3872 3873 This License is a kind of "copyleft", which means that derivative 3874 works of the document must themselves be free in the same sense. 3875 It complements the GNU General Public License, which is a copyleft 3876 license designed for free software. 3877 3878 We have designed this License in order to use it for manuals for 3879 free software, because free software needs free documentation: a 3880 free program should come with manuals providing the same freedoms 3881 that the software does. But this License is not limited to 3882 software manuals; it can be used for any textual work, regardless 3883 of subject matter or whether it is published as a printed book. We 3884 recommend this License principally for works whose purpose is 3885 instruction or reference. 3886 3887 1. APPLICABILITY AND DEFINITIONS 3888 3889 This License applies to any manual or other work, in any medium, 3890 that contains a notice placed by the copyright holder saying it can 3891 be distributed under the terms of this License. Such a notice 3892 grants a world-wide, royalty-free license, unlimited in duration, 3893 to use that work under the conditions stated herein. The 3894 "Document", below, refers to any such manual or work. Any member 3895 of the public is a licensee, and is addressed as "you". You accept 3896 the license if you copy, modify or distribute the work in a way 3897 requiring permission under copyright law. 3898 3899 A "Modified Version" of the Document means any work containing the 3900 Document or a portion of it, either copied verbatim, or with 3901 modifications and/or translated into another language. 3902 3903 A "Secondary Section" is a named appendix or a front-matter section 3904 of the Document that deals exclusively with the relationship of the 3905 publishers or authors of the Document to the Document's overall 3906 subject (or to related matters) and contains nothing that could 3907 fall directly within that overall subject. (Thus, if the Document 3908 is in part a textbook of mathematics, a Secondary Section may not 3909 explain any mathematics.) The relationship could be a matter of 3910 historical connection with the subject or with related matters, or 3911 of legal, commercial, philosophical, ethical or political position 3912 regarding them. 3913 3914 The "Invariant Sections" are certain Secondary Sections whose 3915 titles are designated, as being those of Invariant Sections, in the 3916 notice that says that the Document is released under this License. 3917 If a section does not fit the above definition of Secondary then it 3918 is not allowed to be designated as Invariant. The Document may 3919 contain zero Invariant Sections. If the Document does not identify 3920 any Invariant Sections then there are none. 3921 3922 The "Cover Texts" are certain short passages of text that are 3923 listed, as Front-Cover Texts or Back-Cover Texts, in the notice 3924 that says that the Document is released under this License. A 3925 Front-Cover Text may be at most 5 words, and a Back-Cover Text may 3926 be at most 25 words. 3927 3928 A "Transparent" copy of the Document means a machine-readable copy, 3929 represented in a format whose specification is available to the 3930 general public, that is suitable for revising the document 3931 straightforwardly with generic text editors or (for images composed 3932 of pixels) generic paint programs or (for drawings) some widely 3933 available drawing editor, and that is suitable for input to text 3934 formatters or for automatic translation to a variety of formats 3935 suitable for input to text formatters. A copy made in an otherwise 3936 Transparent file format whose markup, or absence of markup, has 3937 been arranged to thwart or discourage subsequent modification by 3938 readers is not Transparent. An image format is not Transparent if 3939 used for any substantial amount of text. A copy that is not 3940 "Transparent" is called "Opaque". 3941 3942 Examples of suitable formats for Transparent copies include plain 3943 ASCII without markup, Texinfo input format, LaTeX input format, 3944 SGML or XML using a publicly available DTD, and standard-conforming 3945 simple HTML, PostScript or PDF designed for human modification. 3946 Examples of transparent image formats include PNG, XCF and JPG. 3947 Opaque formats include proprietary formats that can be read and 3948 edited only by proprietary word processors, SGML or XML for which 3949 the DTD and/or processing tools are not generally available, and 3950 the machine-generated HTML, PostScript or PDF produced by some word 3951 processors for output purposes only. 3952 3953 The "Title Page" means, for a printed book, the title page itself, 3954 plus such following pages as are needed to hold, legibly, the 3955 material this License requires to appear in the title page. For 3956 works in formats which do not have any title page as such, "Title 3957 Page" means the text near the most prominent appearance of the 3958 work's title, preceding the beginning of the body of the text. 3959 3960 The "publisher" means any person or entity that distributes copies 3961 of the Document to the public. 3962 3963 A section "Entitled XYZ" means a named subunit of the Document 3964 whose title either is precisely XYZ or contains XYZ in parentheses 3965 following text that translates XYZ in another language. (Here XYZ 3966 stands for a specific section name mentioned below, such as 3967 "Acknowledgements", "Dedications", "Endorsements", or "History".) 3968 To "Preserve the Title" of such a section when you modify the 3969 Document means that it remains a section "Entitled XYZ" according 3970 to this definition. 3971 3972 The Document may include Warranty Disclaimers next to the notice 3973 which states that this License applies to the Document. These 3974 Warranty Disclaimers are considered to be included by reference in 3975 this License, but only as regards disclaiming warranties: any other 3976 implication that these Warranty Disclaimers may have is void and 3977 has no effect on the meaning of this License. 3978 3979 2. VERBATIM COPYING 3980 3981 You may copy and distribute the Document in any medium, either 3982 commercially or noncommercially, provided that this License, the 3983 copyright notices, and the license notice saying this License 3984 applies to the Document are reproduced in all copies, and that you 3985 add no other conditions whatsoever to those of this License. You 3986 may not use technical measures to obstruct or control the reading 3987 or further copying of the copies you make or distribute. However, 3988 you may accept compensation in exchange for copies. If you 3989 distribute a large enough number of copies you must also follow the 3990 conditions in section 3. 3991 3992 You may also lend copies, under the same conditions stated above, 3993 and you may publicly display copies. 3994 3995 3. COPYING IN QUANTITY 3996 3997 If you publish printed copies (or copies in media that commonly 3998 have printed covers) of the Document, numbering more than 100, and 3999 the Document's license notice requires Cover Texts, you must 4000 enclose the copies in covers that carry, clearly and legibly, all 4001 these Cover Texts: Front-Cover Texts on the front cover, and 4002 Back-Cover Texts on the back cover. Both covers must also clearly 4003 and legibly identify you as the publisher of these copies. The 4004 front cover must present the full title with all words of the title 4005 equally prominent and visible. You may add other material on the 4006 covers in addition. Copying with changes limited to the covers, as 4007 long as they preserve the title of the Document and satisfy these 4008 conditions, can be treated as verbatim copying in other respects. 4009 4010 If the required texts for either cover are too voluminous to fit 4011 legibly, you should put the first ones listed (as many as fit 4012 reasonably) on the actual cover, and continue the rest onto 4013 adjacent pages. 4014 4015 If you publish or distribute Opaque copies of the Document 4016 numbering more than 100, you must either include a machine-readable 4017 Transparent copy along with each Opaque copy, or state in or with 4018 each Opaque copy a computer-network location from which the general 4019 network-using public has access to download using public-standard 4020 network protocols a complete Transparent copy of the Document, free 4021 of added material. If you use the latter option, you must take 4022 reasonably prudent steps, when you begin distribution of Opaque 4023 copies in quantity, to ensure that this Transparent copy will 4024 remain thus accessible at the stated location until at least one 4025 year after the last time you distribute an Opaque copy (directly or 4026 through your agents or retailers) of that edition to the public. 4027 4028 It is requested, but not required, that you contact the authors of 4029 the Document well before redistributing any large number of copies, 4030 to give them a chance to provide you with an updated version of the 4031 Document. 4032 4033 4. MODIFICATIONS 4034 4035 You may copy and distribute a Modified Version of the Document 4036 under the conditions of sections 2 and 3 above, provided that you 4037 release the Modified Version under precisely this License, with the 4038 Modified Version filling the role of the Document, thus licensing 4039 distribution and modification of the Modified Version to whoever 4040 possesses a copy of it. In addition, you must do these things in 4041 the Modified Version: 4042 4043 A. Use in the Title Page (and on the covers, if any) a title 4044 distinct from that of the Document, and from those of previous 4045 versions (which should, if there were any, be listed in the 4046 History section of the Document). You may use the same title 4047 as a previous version if the original publisher of that 4048 version gives permission. 4049 4050 B. List on the Title Page, as authors, one or more persons or 4051 entities responsible for authorship of the modifications in 4052 the Modified Version, together with at least five of the 4053 principal authors of the Document (all of its principal 4054 authors, if it has fewer than five), unless they release you 4055 from this requirement. 4056 4057 C. State on the Title page the name of the publisher of the 4058 Modified Version, as the publisher. 4059 4060 D. Preserve all the copyright notices of the Document. 4061 4062 E. Add an appropriate copyright notice for your modifications 4063 adjacent to the other copyright notices. 4064 4065 F. Include, immediately after the copyright notices, a license 4066 notice giving the public permission to use the Modified 4067 Version under the terms of this License, in the form shown in 4068 the Addendum below. 4069 4070 G. Preserve in that license notice the full lists of Invariant 4071 Sections and required Cover Texts given in the Document's 4072 license notice. 4073 4074 H. Include an unaltered copy of this License. 4075 4076 I. Preserve the section Entitled "History", Preserve its Title, 4077 and add to it an item stating at least the title, year, new 4078 authors, and publisher of the Modified Version as given on the 4079 Title Page. If there is no section Entitled "History" in the 4080 Document, create one stating the title, year, authors, and 4081 publisher of the Document as given on its Title Page, then add 4082 an item describing the Modified Version as stated in the 4083 previous sentence. 4084 4085 J. Preserve the network location, if any, given in the Document 4086 for public access to a Transparent copy of the Document, and 4087 likewise the network locations given in the Document for 4088 previous versions it was based on. These may be placed in the 4089 "History" section. You may omit a network location for a work 4090 that was published at least four years before the Document 4091 itself, or if the original publisher of the version it refers 4092 to gives permission. 4093 4094 K. For any section Entitled "Acknowledgements" or "Dedications", 4095 Preserve the Title of the section, and preserve in the section 4096 all the substance and tone of each of the contributor 4097 acknowledgements and/or dedications given therein. 4098 4099 L. Preserve all the Invariant Sections of the Document, unaltered 4100 in their text and in their titles. Section numbers or the 4101 equivalent are not considered part of the section titles. 4102 4103 M. Delete any section Entitled "Endorsements". Such a section 4104 may not be included in the Modified Version. 4105 4106 N. Do not retitle any existing section to be Entitled 4107 "Endorsements" or to conflict in title with any Invariant 4108 Section. 4109 4110 O. Preserve any Warranty Disclaimers. 4111 4112 If the Modified Version includes new front-matter sections or 4113 appendices that qualify as Secondary Sections and contain no 4114 material copied from the Document, you may at your option designate 4115 some or all of these sections as invariant. To do this, add their 4116 titles to the list of Invariant Sections in the Modified Version's 4117 license notice. These titles must be distinct from any other 4118 section titles. 4119 4120 You may add a section Entitled "Endorsements", provided it contains 4121 nothing but endorsements of your Modified Version by various 4122 parties--for example, statements of peer review or that the text 4123 has been approved by an organization as the authoritative 4124 definition of a standard. 4125 4126 You may add a passage of up to five words as a Front-Cover Text, 4127 and a passage of up to 25 words as a Back-Cover Text, to the end of 4128 the list of Cover Texts in the Modified Version. Only one passage 4129 of Front-Cover Text and one of Back-Cover Text may be added by (or 4130 through arrangements made by) any one entity. If the Document 4131 already includes a cover text for the same cover, previously added 4132 by you or by arrangement made by the same entity you are acting on 4133 behalf of, you may not add another; but you may replace the old 4134 one, on explicit permission from the previous publisher that added 4135 the old one. 4136 4137 The author(s) and publisher(s) of the Document do not by this 4138 License give permission to use their names for publicity for or to 4139 assert or imply endorsement of any Modified Version. 4140 4141 5. COMBINING DOCUMENTS 4142 4143 You may combine the Document with other documents released under 4144 this License, under the terms defined in section 4 above for 4145 modified versions, provided that you include in the combination all 4146 of the Invariant Sections of all of the original documents, 4147 unmodified, and list them all as Invariant Sections of your 4148 combined work in its license notice, and that you preserve all 4149 their Warranty Disclaimers. 4150 4151 The combined work need only contain one copy of this License, and 4152 multiple identical Invariant Sections may be replaced with a single 4153 copy. If there are multiple Invariant Sections with the same name 4154 but different contents, make the title of each such section unique 4155 by adding at the end of it, in parentheses, the name of the 4156 original author or publisher of that section if known, or else a 4157 unique number. Make the same adjustment to the section titles in 4158 the list of Invariant Sections in the license notice of the 4159 combined work. 4160 4161 In the combination, you must combine any sections Entitled 4162 "History" in the various original documents, forming one section 4163 Entitled "History"; likewise combine any sections Entitled 4164 "Acknowledgements", and any sections Entitled "Dedications". You 4165 must delete all sections Entitled "Endorsements." 4166 4167 6. COLLECTIONS OF DOCUMENTS 4168 4169 You may make a collection consisting of the Document and other 4170 documents released under this License, and replace the individual 4171 copies of this License in the various documents with a single copy 4172 that is included in the collection, provided that you follow the 4173 rules of this License for verbatim copying of each of the documents 4174 in all other respects. 4175 4176 You may extract a single document from such a collection, and 4177 distribute it individually under this License, provided you insert 4178 a copy of this License into the extracted document, and follow this 4179 License in all other respects regarding verbatim copying of that 4180 document. 4181 4182 7. AGGREGATION WITH INDEPENDENT WORKS 4183 4184 A compilation of the Document or its derivatives with other 4185 separate and independent documents or works, in or on a volume of a 4186 storage or distribution medium, is called an "aggregate" if the 4187 copyright resulting from the compilation is not used to limit the 4188 legal rights of the compilation's users beyond what the individual 4189 works permit. When the Document is included in an aggregate, this 4190 License does not apply to the other works in the aggregate which 4191 are not themselves derivative works of the Document. 4192 4193 If the Cover Text requirement of section 3 is applicable to these 4194 copies of the Document, then if the Document is less than one half 4195 of the entire aggregate, the Document's Cover Texts may be placed 4196 on covers that bracket the Document within the aggregate, or the 4197 electronic equivalent of covers if the Document is in electronic 4198 form. Otherwise they must appear on printed covers that bracket 4199 the whole aggregate. 4200 4201 8. TRANSLATION 4202 4203 Translation is considered a kind of modification, so you may 4204 distribute translations of the Document under the terms of section 4205 4. Replacing Invariant Sections with translations requires special 4206 permission from their copyright holders, but you may include 4207 translations of some or all Invariant Sections in addition to the 4208 original versions of these Invariant Sections. You may include a 4209 translation of this License, and all the license notices in the 4210 Document, and any Warranty Disclaimers, provided that you also 4211 include the original English version of this License and the 4212 original versions of those notices and disclaimers. In case of a 4213 disagreement between the translation and the original version of 4214 this License or a notice or disclaimer, the original version will 4215 prevail. 4216 4217 If a section in the Document is Entitled "Acknowledgements", 4218 "Dedications", or "History", the requirement (section 4) to 4219 Preserve its Title (section 1) will typically require changing the 4220 actual title. 4221 4222 9. TERMINATION 4223 4224 You may not copy, modify, sublicense, or distribute the Document 4225 except as expressly provided under this License. Any attempt 4226 otherwise to copy, modify, sublicense, or distribute it is void, 4227 and will automatically terminate your rights under this License. 4228 4229 However, if you cease all violation of this License, then your 4230 license from a particular copyright holder is reinstated (a) 4231 provisionally, unless and until the copyright holder explicitly and 4232 finally terminates your license, and (b) permanently, if the 4233 copyright holder fails to notify you of the violation by some 4234 reasonable means prior to 60 days after the cessation. 4235 4236 Moreover, your license from a particular copyright holder is 4237 reinstated permanently if the copyright holder notifies you of the 4238 violation by some reasonable means, this is the first time you have 4239 received notice of violation of this License (for any work) from 4240 that copyright holder, and you cure the violation prior to 30 days 4241 after your receipt of the notice. 4242 4243 Termination of your rights under this section does not terminate 4244 the licenses of parties who have received copies or rights from you 4245 under this License. If your rights have been terminated and not 4246 permanently reinstated, receipt of a copy of some or all of the 4247 same material does not give you any rights to use it. 4248 4249 10. FUTURE REVISIONS OF THIS LICENSE 4250 4251 The Free Software Foundation may publish new, revised versions of 4252 the GNU Free Documentation License from time to time. Such new 4253 versions will be similar in spirit to the present version, but may 4254 differ in detail to address new problems or concerns. See 4255 <http://www.gnu.org/copyleft/>. 4256 4257 Each version of the License is given a distinguishing version 4258 number. If the Document specifies that a particular numbered 4259 version of this License "or any later version" applies to it, you 4260 have the option of following the terms and conditions either of 4261 that specified version or of any later version that has been 4262 published (not as a draft) by the Free Software Foundation. If the 4263 Document does not specify a version number of this License, you may 4264 choose any version ever published (not as a draft) by the Free 4265 Software Foundation. If the Document specifies that a proxy can 4266 decide which future versions of this License can be used, that 4267 proxy's public statement of acceptance of a version permanently 4268 authorizes you to choose that version for the Document. 4269 4270 11. RELICENSING 4271 4272 "Massive Multiauthor Collaboration Site" (or "MMC Site") means any 4273 World Wide Web server that publishes copyrightable works and also 4274 provides prominent facilities for anybody to edit those works. A 4275 public wiki that anybody can edit is an example of such a server. 4276 A "Massive Multiauthor Collaboration" (or "MMC") contained in the 4277 site means any set of copyrightable works thus published on the MMC 4278 site. 4279 4280 "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 4281 license published by Creative Commons Corporation, a not-for-profit 4282 corporation with a principal place of business in San Francisco, 4283 California, as well as future copyleft versions of that license 4284 published by that same organization. 4285 4286 "Incorporate" means to publish or republish a Document, in whole or 4287 in part, as part of another Document. 4288 4289 An MMC is "eligible for relicensing" if it is licensed under this 4290 License, and if all works that were first published under this 4291 License somewhere other than this MMC, and subsequently 4292 incorporated in whole or in part into the MMC, (1) had no cover 4293 texts or invariant sections, and (2) were thus incorporated prior 4294 to November 1, 2008. 4295 4296 The operator of an MMC Site may republish an MMC contained in the 4297 site under CC-BY-SA on the same site at any time before August 1, 4298 2009, provided the MMC is eligible for relicensing. 4299 4300 ADDENDUM: How to use this License for your documents 4301 ==================================================== 4302 4303 To use this License in a document you have written, include a copy of 4304 the License in the document and put the following copyright and license 4305 notices just after the title page: 4306 4307 Copyright (C) YEAR YOUR NAME. 4308 Permission is granted to copy, distribute and/or modify this document 4309 under the terms of the GNU Free Documentation License, Version 1.3 4310 or any later version published by the Free Software Foundation; 4311 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover 4312 Texts. A copy of the license is included in the section entitled ``GNU 4313 Free Documentation License''. 4314 4315 If you have Invariant Sections, Front-Cover Texts and Back-Cover 4316 Texts, replace the "with...Texts." line with this: 4317 4318 with the Invariant Sections being LIST THEIR TITLES, with 4319 the Front-Cover Texts being LIST, and with the Back-Cover Texts 4320 being LIST. 4321 4322 If you have Invariant Sections without Cover Texts, or some other 4323 combination of the three, merge those two alternatives to suit the 4324 situation. 4325 4326 If your document contains nontrivial examples of program code, we 4327 recommend releasing these examples in parallel under your choice of free 4328 software license, such as the GNU General Public License, to permit 4329 their use in free software. 4330 4331 4332 File: libgomp.info, Node: Funding, Next: Library Index, Prev: GNU Free Documentation License, Up: Top 4333 4334 Funding Free Software 4335 ********************* 4336 4337 If you want to have more free software a few years from now, it makes 4338 sense for you to help encourage people to contribute funds for its 4339 development. The most effective approach known is to encourage 4340 commercial redistributors to donate. 4341 4342 Users of free software systems can boost the pace of development by 4343 encouraging for-a-fee distributors to donate part of their selling price 4344 to free software developers--the Free Software Foundation, and others. 4345 4346 The way to convince distributors to do this is to demand it and 4347 expect it from them. So when you compare distributors, judge them 4348 partly by how much they give to free software development. Show 4349 distributors they must compete to be the one who gives the most. 4350 4351 To make this approach work, you must insist on numbers that you can 4352 compare, such as, "We will donate ten dollars to the Frobnitz project 4353 for each disk sold." Don't be satisfied with a vague promise, such as 4354 "A portion of the profits are donated," since it doesn't give a basis 4355 for comparison. 4356 4357 Even a precise fraction "of the profits from this disk" is not very 4358 meaningful, since creative accounting and unrelated business decisions 4359 can greatly alter what fraction of the sales price counts as profit. If 4360 the price you pay is $50, ten percent of the profit is probably less 4361 than a dollar; it might be a few cents, or nothing at all. 4362 4363 Some redistributors do development work themselves. This is useful 4364 too; but to keep everyone honest, you need to inquire how much they do, 4365 and what kind. Some kinds of development make much more long-term 4366 difference than others. For example, maintaining a separate version of 4367 a program contributes very little; maintaining the standard version of a 4368 program for the whole community contributes much. Easy new ports 4369 contribute little, since someone else would surely do them; difficult 4370 ports such as adding a new CPU to the GNU Compiler Collection contribute 4371 more; major new features or packages contribute the most. 4372 4373 By establishing the idea that supporting further development is "the 4374 proper thing to do" when distributing free software for a fee, we can 4375 assure a steady flow of resources into making more free software. 4376 4377 Copyright (C) 1994 Free Software Foundation, Inc. 4378 Verbatim copying and redistribution of this section is permitted 4379 without royalty; alteration is not permitted. 4380 4381 4382 File: libgomp.info, Node: Library Index, Prev: Funding, Up: Top 4383 4384 Library Index 4385 ************* 4386 4387 [index] 4388 * Menu: 4389 4390 * Environment Variable: OMP_CANCELLATION. (line 6) 4391 * Environment Variable <1>: OMP_DISPLAY_ENV. (line 6) 4392 * Environment Variable <2>: OMP_DEFAULT_DEVICE. (line 6) 4393 * Environment Variable <3>: OMP_DYNAMIC. (line 6) 4394 * Environment Variable <4>: OMP_MAX_ACTIVE_LEVELS. (line 6) 4395 * Environment Variable <5>: OMP_MAX_TASK_PRIORITY. (line 6) 4396 * Environment Variable <6>: OMP_NESTED. (line 6) 4397 * Environment Variable <7>: OMP_NUM_THREADS. (line 6) 4398 * Environment Variable <8>: OMP_PROC_BIND. (line 6) 4399 * Environment Variable <9>: OMP_PLACES. (line 6) 4400 * Environment Variable <10>: OMP_STACKSIZE. (line 6) 4401 * Environment Variable <11>: OMP_SCHEDULE. (line 6) 4402 * Environment Variable <12>: OMP_THREAD_LIMIT. (line 6) 4403 * Environment Variable <13>: OMP_WAIT_POLICY. (line 6) 4404 * Environment Variable <14>: GOMP_CPU_AFFINITY. (line 6) 4405 * Environment Variable <15>: GOMP_DEBUG. (line 6) 4406 * Environment Variable <16>: GOMP_STACKSIZE. (line 6) 4407 * Environment Variable <17>: GOMP_SPINCOUNT. (line 6) 4408 * Environment Variable <18>: GOMP_RTEMS_THREAD_POOLS. 4409 (line 6) 4410 * FDL, GNU Free Documentation License: GNU Free Documentation License. 4411 (line 6) 4412 * Implementation specific setting: OMP_NESTED. (line 6) 4413 * Implementation specific setting <1>: OMP_NUM_THREADS. (line 6) 4414 * Implementation specific setting <2>: OMP_SCHEDULE. (line 6) 4415 * Implementation specific setting <3>: GOMP_STACKSIZE. (line 6) 4416 * Implementation specific setting <4>: GOMP_SPINCOUNT. (line 6) 4417 * Implementation specific setting <5>: GOMP_RTEMS_THREAD_POOLS. 4418 (line 6) 4419 * Introduction: Top. (line 6) 4420 4421 4422 4423 Tag Table: 4424 Node: Top2083 4425 Node: Enabling OpenMP4489 4426 Node: Runtime Library Routines5276 4427 Node: omp_get_active_level8339 4428 Node: omp_get_ancestor_thread_num9039 4429 Node: omp_get_cancellation9969 4430 Node: omp_get_default_device10783 4431 Node: omp_get_dynamic11459 4432 Node: omp_get_level12334 4433 Node: omp_get_max_active_levels12954 4434 Node: omp_get_max_task_priority13659 4435 Node: omp_get_max_threads14279 4436 Node: omp_get_nested15036 4437 Node: omp_get_num_devices15950 4438 Node: omp_get_num_procs16471 4439 Node: omp_get_num_teams17010 4440 Node: omp_get_num_threads17526 4441 Node: omp_get_proc_bind18615 4442 Node: omp_get_schedule19536 4443 Node: omp_get_team_num20490 4444 Node: omp_get_team_size20989 4445 Node: omp_get_thread_limit21949 4446 Node: omp_get_thread_num22568 4447 Node: omp_in_parallel23439 4448 Node: omp_in_final24088 4449 Node: omp_is_initial_device24762 4450 Node: omp_set_default_device25455 4451 Node: omp_set_dynamic26246 4452 Node: omp_set_max_active_levels27132 4453 Node: omp_set_nested27909 4454 Node: omp_set_num_threads28801 4455 Node: omp_set_schedule29669 4456 Node: omp_init_lock30750 4457 Node: omp_set_lock31403 4458 Node: omp_test_lock32258 4459 Node: omp_unset_lock33234 4460 Node: omp_destroy_lock34165 4461 Node: omp_init_nest_lock34842 4462 Node: omp_set_nest_lock35577 4463 Node: omp_test_nest_lock36492 4464 Node: omp_unset_nest_lock37519 4465 Node: omp_destroy_nest_lock38534 4466 Node: omp_get_wtick39285 4467 Node: omp_get_wtime39877 4468 Node: Environment Variables40653 4469 Node: OMP_CANCELLATION42208 4470 Node: OMP_DISPLAY_ENV42741 4471 Node: OMP_DEFAULT_DEVICE43444 4472 Node: OMP_DYNAMIC44224 4473 Node: OMP_MAX_ACTIVE_LEVELS44820 4474 Node: OMP_MAX_TASK_PRIORITY45470 4475 Node: OMP_NESTED46128 4476 Node: OMP_NUM_THREADS46733 4477 Node: OMP_PROC_BIND47421 4478 Node: OMP_PLACES48613 4479 Node: OMP_STACKSIZE50790 4480 Node: OMP_SCHEDULE51614 4481 Node: OMP_THREAD_LIMIT52312 4482 Node: OMP_WAIT_POLICY52912 4483 Node: GOMP_CPU_AFFINITY53604 4484 Node: GOMP_DEBUG55334 4485 Node: GOMP_STACKSIZE55841 4486 Node: GOMP_SPINCOUNT56670 4487 Node: GOMP_RTEMS_THREAD_POOLS57874 4488 Node: Enabling OpenACC60052 4489 Node: OpenACC Runtime Library Routines61045 4490 Node: acc_get_num_devices64839 4491 Node: acc_set_device_type65565 4492 Node: acc_get_device_type66329 4493 Node: acc_set_device_num67044 4494 Node: acc_get_device_num67828 4495 Node: acc_async_test68625 4496 Node: acc_async_test_all69617 4497 Node: acc_wait70517 4498 Node: acc_wait_all71152 4499 Node: acc_wait_all_async71731 4500 Node: acc_wait_async72483 4501 Node: acc_init73190 4502 Node: acc_shutdown73836 4503 Node: acc_on_device74504 4504 Node: acc_malloc75508 4505 Node: acc_free76007 4506 Node: acc_copyin76434 4507 Node: acc_present_or_copyin77544 4508 Node: acc_create79170 4509 Node: acc_present_or_create80325 4510 Node: acc_copyout81959 4511 Node: acc_delete82982 4512 Node: acc_update_device83957 4513 Node: acc_update_self85069 4514 Node: acc_map_data86173 4515 Node: acc_unmap_data86858 4516 Node: acc_deviceptr87379 4517 Node: acc_hostptr87949 4518 Node: acc_is_present88513 4519 Node: acc_memcpy_to_device90040 4520 Node: acc_memcpy_from_device90703 4521 Node: acc_get_current_cuda_device91387 4522 Node: acc_get_current_cuda_context91984 4523 Node: acc_get_cuda_stream92578 4524 Node: acc_set_cuda_stream93134 4525 Node: OpenACC Environment Variables93666 4526 Node: ACC_DEVICE_TYPE94125 4527 Node: ACC_DEVICE_NUM94361 4528 Node: GCC_ACC_NOTIFY94618 4529 Node: CUDA Streams Usage94841 4530 Ref: CUDA Streams Usage-Footnote-196741 4531 Node: OpenACC Library Interoperability96850 4532 Ref: OpenACC Library Interoperability-Footnote-1103206 4533 Ref: OpenACC Library Interoperability-Footnote-2103458 4534 Node: The libgomp ABI103666 4535 Node: Implementing MASTER construct104522 4536 Node: Implementing CRITICAL construct104936 4537 Node: Implementing ATOMIC construct105675 4538 Node: Implementing FLUSH construct106156 4539 Node: Implementing BARRIER construct106427 4540 Node: Implementing THREADPRIVATE construct106696 4541 Node: Implementing PRIVATE clause107349 4542 Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses107930 4543 Node: Implementing REDUCTION clause109254 4544 Node: Implementing PARALLEL construct109811 4545 Node: Implementing FOR construct111068 4546 Node: Implementing ORDERED construct113066 4547 Node: Implementing SECTIONS construct113372 4548 Node: Implementing SINGLE construct114138 4549 Node: Implementing OpenACC's PARALLEL construct114850 4550 Node: Reporting Bugs115108 4551 Node: Copying115470 4552 Node: GNU Free Documentation License153017 4553 Node: Funding178140 4554 Node: Library Index180666 4555 4556 End Tag Table 4557
Indexes created Fri Mar 20 00:23:26 UTC 2026