1 /* Copyright (C) 2005-2019 Free Software Foundation, Inc.
2    Contributed by Richard Henderson <rth@redhat.com>.
3 
4    This file is part of the GNU Offloading and Multi Processing Library
5    (libgomp).
6 
7    Libgomp is free software; you can redistribute it and/or modify it
8    under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3, or (at your option)
10    any later version.
11 
12    Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
13    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14    FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15    more details.
16 
17    Under Section 7 of GPL version 3, you are granted additional
18    permissions described in the GCC Runtime Library Exception, version
19    3.1, as published by the Free Software Foundation.
20 
21    You should have received a copy of the GNU General Public License and
22    a copy of the GCC Runtime Library Exception along with this program;
23    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
24    <http://www.gnu.org/licenses/>.  */
25 
26 /* This file contains data types and function declarations that are not
27    part of the official OpenACC or OpenMP user interfaces.  There are
28    declarations in here that are part of the GNU Offloading and Multi
29    Processing ABI, in that the compiler is required to know about them
30    and use them.
31 
32    The convention is that the all caps prefix "GOMP" is used group items
33    that are part of the external ABI, and the lower case prefix "gomp"
34    is used group items that are completely private to the library.  */
35 
36 #ifndef LIBGOMP_H
37 #define LIBGOMP_H 1
38 
39 #ifndef _LIBGOMP_CHECKING_
40 /* Define to 1 to perform internal sanity checks.  */
41 #define _LIBGOMP_CHECKING_ 0
42 #endif
43 
44 #include "config.h"
45 #include "gstdint.h"
46 #include "libgomp-plugin.h"
47 #include "gomp-constants.h"
48 
49 #ifdef HAVE_PTHREAD_H
50 #include <pthread.h>
51 #endif
52 #include <stdbool.h>
53 #include <stdlib.h>
54 #include <stdarg.h>
55 
56 /* Needed for memset in priority_queue.c.  */
57 #if _LIBGOMP_CHECKING_
58 # ifdef STRING_WITH_STRINGS
59 #  include <string.h>
60 #  include <strings.h>
61 # else
62 #  ifdef HAVE_STRING_H
63 #   include <string.h>
64 #  else
65 #   ifdef HAVE_STRINGS_H
66 #    include <strings.h>
67 #   endif
68 #  endif
69 # endif
70 #endif
71 
72 #ifdef HAVE_ATTRIBUTE_VISIBILITY
73 # pragma GCC visibility push(hidden)
74 #endif
75 
76 /* If we were a C++ library, we'd get this from <std/atomic>.  */
77 enum memmodel
78 {
79   MEMMODEL_RELAXED = 0,
80   MEMMODEL_CONSUME = 1,
81   MEMMODEL_ACQUIRE = 2,
82   MEMMODEL_RELEASE = 3,
83   MEMMODEL_ACQ_REL = 4,
84   MEMMODEL_SEQ_CST = 5
85 };
86 
87 /* alloc.c */
88 
89 #if defined(HAVE_ALIGNED_ALLOC) \
90     || defined(HAVE__ALIGNED_MALLOC) \
91     || defined(HAVE_POSIX_MEMALIGN) \
92     || defined(HAVE_MEMALIGN)
93 /* Defined if gomp_aligned_alloc doesn't use fallback version
94    and free can be used instead of gomp_aligned_free.  */
95 #define GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC 1
96 #endif
97 
98 extern void *gomp_malloc (size_t) __attribute__((malloc));
99 extern void *gomp_malloc_cleared (size_t) __attribute__((malloc));
100 extern void *gomp_realloc (void *, size_t);
101 extern void *gomp_aligned_alloc (size_t, size_t)
102   __attribute__((malloc, alloc_size (2)));
103 extern void gomp_aligned_free (void *);
104 
105 /* Avoid conflicting prototypes of alloca() in system headers by using
106    GCC's builtin alloca().  */
107 #define gomp_alloca(x)  __builtin_alloca(x)
108 
109 /* error.c */
110 
111 extern void gomp_vdebug (int, const char *, va_list);
112 extern void gomp_debug (int, const char *, ...)
113 	__attribute__ ((format (printf, 2, 3)));
114 #define gomp_vdebug(KIND, FMT, VALIST) \
115   do { \
116     if (__builtin_expect (gomp_debug_var, 0)) \
117       (gomp_vdebug) ((KIND), (FMT), (VALIST)); \
118   } while (0)
119 #define gomp_debug(KIND, ...) \
120   do { \
121     if (__builtin_expect (gomp_debug_var, 0)) \
122       (gomp_debug) ((KIND), __VA_ARGS__); \
123   } while (0)
124 extern void gomp_verror (const char *, va_list);
125 extern void gomp_error (const char *, ...)
126 	__attribute__ ((format (printf, 1, 2)));
127 extern void gomp_vfatal (const char *, va_list)
128 	__attribute__ ((noreturn));
129 extern void gomp_fatal (const char *, ...)
130 	__attribute__ ((noreturn, format (printf, 1, 2)));
131 
132 struct gomp_task;
133 struct gomp_taskgroup;
134 struct htab;
135 
136 #include "priority_queue.h"
137 #include "sem.h"
138 #include "mutex.h"
139 #include "bar.h"
140 #include "simple-bar.h"
141 #include "ptrlock.h"
142 
143 
144 /* This structure contains the data to control one work-sharing construct,
145    either a LOOP (FOR/DO) or a SECTIONS.  */
146 
147 enum gomp_schedule_type
148 {
149   GFS_RUNTIME,
150   GFS_STATIC,
151   GFS_DYNAMIC,
152   GFS_GUIDED,
153   GFS_AUTO,
154   GFS_MONOTONIC = 0x80000000U
155 };
156 
157 struct gomp_doacross_work_share
158 {
159   union {
160     /* chunk_size copy, as ws->chunk_size is multiplied by incr for
161        GFS_DYNAMIC.  */
162     long chunk_size;
163     /* Likewise, but for ull implementation.  */
164     unsigned long long chunk_size_ull;
165     /* For schedule(static,0) this is the number
166        of iterations assigned to the last thread, i.e. number of
167        iterations / number of threads.  */
168     long q;
169     /* Likewise, but for ull implementation.  */
170     unsigned long long q_ull;
171   };
172   /* Size of each array entry (padded to cache line size).  */
173   unsigned long elt_sz;
174   /* Number of dimensions in sink vectors.  */
175   unsigned int ncounts;
176   /* True if the iterations can be flattened.  */
177   bool flattened;
178   /* Actual array (of elt_sz sized units), aligned to cache line size.
179      This is indexed by team_id for GFS_STATIC and outermost iteration
180      / chunk_size for other schedules.  */
181   unsigned char *array;
182   /* These two are only used for schedule(static,0).  */
183   /* This one is number of iterations % number of threads.  */
184   long t;
185   union {
186     /* And this one is cached t * (q + 1).  */
187     long boundary;
188     /* Likewise, but for the ull implementation.  */
189     unsigned long long boundary_ull;
190   };
191   /* Pointer to extra memory if needed for lastprivate(conditional).  */
192   void *extra;
193   /* Array of shift counts for each dimension if they can be flattened.  */
194   unsigned int shift_counts[];
195 };
196 
197 struct gomp_work_share
198 {
199   /* This member records the SCHEDULE clause to be used for this construct.
200      The user specification of "runtime" will already have been resolved.
201      If this is a SECTIONS construct, this value will always be DYNAMIC.  */
202   enum gomp_schedule_type sched;
203 
204   int mode;
205 
206   union {
207     struct {
208       /* This is the chunk_size argument to the SCHEDULE clause.  */
209       long chunk_size;
210 
211       /* This is the iteration end point.  If this is a SECTIONS construct,
212 	 this is the number of contained sections.  */
213       long end;
214 
215       /* This is the iteration step.  If this is a SECTIONS construct, this
216 	 is always 1.  */
217       long incr;
218     };
219 
220     struct {
221       /* The same as above, but for the unsigned long long loop variants.  */
222       unsigned long long chunk_size_ull;
223       unsigned long long end_ull;
224       unsigned long long incr_ull;
225     };
226   };
227 
228   union {
229     /* This is a circular queue that details which threads will be allowed
230        into the ordered region and in which order.  When a thread allocates
231        iterations on which it is going to work, it also registers itself at
232        the end of the array.  When a thread reaches the ordered region, it
233        checks to see if it is the one at the head of the queue.  If not, it
234        blocks on its RELEASE semaphore.  */
235     unsigned *ordered_team_ids;
236 
237     /* This is a pointer to DOACROSS work share data.  */
238     struct gomp_doacross_work_share *doacross;
239   };
240 
241   /* This is the number of threads that have registered themselves in
242      the circular queue ordered_team_ids.  */
243   unsigned ordered_num_used;
244 
245   /* This is the team_id of the currently acknowledged owner of the ordered
246      section, or -1u if the ordered section has not been acknowledged by
247      any thread.  This is distinguished from the thread that is *allowed*
248      to take the section next.  */
249   unsigned ordered_owner;
250 
251   /* This is the index into the circular queue ordered_team_ids of the
252      current thread that's allowed into the ordered reason.  */
253   unsigned ordered_cur;
254 
255   /* This is a chain of allocated gomp_work_share blocks, valid only
256      in the first gomp_work_share struct in the block.  */
257   struct gomp_work_share *next_alloc;
258 
259   /* The above fields are written once during workshare initialization,
260      or related to ordered worksharing.  Make sure the following fields
261      are in a different cache line.  */
262 
263   /* This lock protects the update of the following members.  */
264   gomp_mutex_t lock __attribute__((aligned (64)));
265 
266   /* This is the count of the number of threads that have exited the work
267      share construct.  If the construct was marked nowait, they have moved on
268      to other work; otherwise they're blocked on a barrier.  The last member
269      of the team to exit the work share construct must deallocate it.  */
270   unsigned threads_completed;
271 
272   union {
273     /* This is the next iteration value to be allocated.  In the case of
274        GFS_STATIC loops, this the iteration start point and never changes.  */
275     long next;
276 
277     /* The same, but with unsigned long long type.  */
278     unsigned long long next_ull;
279 
280     /* This is the returned data structure for SINGLE COPYPRIVATE.  */
281     void *copyprivate;
282   };
283 
284   union {
285     /* Link to gomp_work_share struct for next work sharing construct
286        encountered after this one.  */
287     gomp_ptrlock_t next_ws;
288 
289     /* gomp_work_share structs are chained in the free work share cache
290        through this.  */
291     struct gomp_work_share *next_free;
292   };
293 
294   /* Task reductions for this work-sharing construct.  */
295   uintptr_t *task_reductions;
296 
297   /* If only few threads are in the team, ordered_team_ids can point
298      to this array which fills the padding at the end of this struct.  */
299   unsigned inline_ordered_team_ids[0];
300 };
301 
302 /* This structure contains all of the thread-local data associated with
303    a thread team.  This is the data that must be saved when a thread
304    encounters a nested PARALLEL construct.  */
305 
306 struct gomp_team_state
307 {
308   /* This is the team of which the thread is currently a member.  */
309   struct gomp_team *team;
310 
311   /* This is the work share construct which this thread is currently
312      processing.  Recall that with NOWAIT, not all threads may be
313      processing the same construct.  */
314   struct gomp_work_share *work_share;
315 
316   /* This is the previous work share construct or NULL if there wasn't any.
317      When all threads are done with the current work sharing construct,
318      the previous one can be freed.  The current one can't, as its
319      next_ws field is used.  */
320   struct gomp_work_share *last_work_share;
321 
322   /* This is the ID of this thread within the team.  This value is
323      guaranteed to be between 0 and N-1, where N is the number of
324      threads in the team.  */
325   unsigned team_id;
326 
327   /* Nesting level.  */
328   unsigned level;
329 
330   /* Active nesting level.  Only active parallel regions are counted.  */
331   unsigned active_level;
332 
333   /* Place-partition-var, offset and length into gomp_places_list array.  */
334   unsigned place_partition_off;
335   unsigned place_partition_len;
336 
337 #ifdef HAVE_SYNC_BUILTINS
338   /* Number of single stmts encountered.  */
339   unsigned long single_count;
340 #endif
341 
342   /* For GFS_RUNTIME loops that resolved to GFS_STATIC, this is the
343      trip number through the loop.  So first time a particular loop
344      is encountered this number is 0, the second time through the loop
345      is 1, etc.  This is unused when the compiler knows in advance that
346      the loop is statically scheduled.  */
347   unsigned long static_trip;
348 };
349 
350 struct target_mem_desc;
351 
352 /* These are the OpenMP 4.0 Internal Control Variables described in
353    section 2.3.1.  Those described as having one copy per task are
354    stored within the structure; those described as having one copy
355    for the whole program are (naturally) global variables.  */
356 
357 struct gomp_task_icv
358 {
359   unsigned long nthreads_var;
360   enum gomp_schedule_type run_sched_var;
361   int run_sched_chunk_size;
362   int default_device_var;
363   unsigned int thread_limit_var;
364   bool dyn_var;
365   bool nest_var;
366   char bind_var;
367   /* Internal ICV.  */
368   struct target_mem_desc *target_data;
369 };
370 
371 extern struct gomp_task_icv gomp_global_icv;
372 #ifndef HAVE_SYNC_BUILTINS
373 extern gomp_mutex_t gomp_managed_threads_lock;
374 #endif
375 extern unsigned long gomp_max_active_levels_var;
376 extern bool gomp_cancel_var;
377 extern int gomp_max_task_priority_var;
378 extern unsigned long long gomp_spin_count_var, gomp_throttled_spin_count_var;
379 extern unsigned long gomp_available_cpus, gomp_managed_threads;
380 extern unsigned long *gomp_nthreads_var_list, gomp_nthreads_var_list_len;
381 extern char *gomp_bind_var_list;
382 extern unsigned long gomp_bind_var_list_len;
383 extern void **gomp_places_list;
384 extern unsigned long gomp_places_list_len;
385 extern unsigned int gomp_num_teams_var;
386 extern int gomp_debug_var;
387 extern bool gomp_display_affinity_var;
388 extern char *gomp_affinity_format_var;
389 extern size_t gomp_affinity_format_len;
390 extern int goacc_device_num;
391 extern char *goacc_device_type;
392 extern int goacc_default_dims[GOMP_DIM_MAX];
393 
394 enum gomp_task_kind
395 {
396   /* Implicit task.  */
397   GOMP_TASK_IMPLICIT,
398   /* Undeferred task.  */
399   GOMP_TASK_UNDEFERRED,
400   /* Task created by GOMP_task and waiting to be run.  */
401   GOMP_TASK_WAITING,
402   /* Task currently executing or scheduled and about to execute.  */
403   GOMP_TASK_TIED,
404   /* Used for target tasks that have vars mapped and async run started,
405      but not yet completed.  Once that completes, they will be readded
406      into the queues as GOMP_TASK_WAITING in order to perform the var
407      unmapping.  */
408   GOMP_TASK_ASYNC_RUNNING
409 };
410 
411 struct gomp_task_depend_entry
412 {
413   /* Address of dependency.  */
414   void *addr;
415   struct gomp_task_depend_entry *next;
416   struct gomp_task_depend_entry *prev;
417   /* Task that provides the dependency in ADDR.  */
418   struct gomp_task *task;
419   /* Depend entry is of type "IN".  */
420   bool is_in;
421   bool redundant;
422   bool redundant_out;
423 };
424 
425 struct gomp_dependers_vec
426 {
427   size_t n_elem;
428   size_t allocated;
429   struct gomp_task *elem[];
430 };
431 
432 /* Used when in GOMP_taskwait or in gomp_task_maybe_wait_for_dependencies.  */
433 
434 struct gomp_taskwait
435 {
436   bool in_taskwait;
437   bool in_depend_wait;
438   /* Number of tasks we are waiting for.  */
439   size_t n_depend;
440   gomp_sem_t taskwait_sem;
441 };
442 
443 /* This structure describes a "task" to be run by a thread.  */
444 
445 struct gomp_task
446 {
447   /* Parent of this task.  */
448   struct gomp_task *parent;
449   /* Children of this task.  */
450   struct priority_queue children_queue;
451   /* Taskgroup this task belongs in.  */
452   struct gomp_taskgroup *taskgroup;
453   /* Tasks that depend on this task.  */
454   struct gomp_dependers_vec *dependers;
455   struct htab *depend_hash;
456   struct gomp_taskwait *taskwait;
457   /* Number of items in DEPEND.  */
458   size_t depend_count;
459   /* Number of tasks this task depends on.  Once this counter reaches
460      0, we have no unsatisfied dependencies, and this task can be put
461      into the various queues to be scheduled.  */
462   size_t num_dependees;
463 
464   /* Priority of this task.  */
465   int priority;
466   /* The priority node for this task in each of the different queues.
467      We put this here to avoid allocating space for each priority
468      node.  Then we play offsetof() games to convert between pnode[]
469      entries and the gomp_task in which they reside.  */
470   struct priority_node pnode[3];
471 
472   struct gomp_task_icv icv;
473   void (*fn) (void *);
474   void *fn_data;
475   enum gomp_task_kind kind;
476   bool in_tied_task;
477   bool final_task;
478   bool copy_ctors_done;
479   /* Set for undeferred tasks with unsatisfied dependencies which
480      block further execution of their parent until the dependencies
481      are satisfied.  */
482   bool parent_depends_on;
483   /* Dependencies provided and/or needed for this task.  DEPEND_COUNT
484      is the number of items available.  */
485   struct gomp_task_depend_entry depend[];
486 };
487 
488 /* This structure describes a single #pragma omp taskgroup.  */
489 
490 struct gomp_taskgroup
491 {
492   struct gomp_taskgroup *prev;
493   /* Queue of tasks that belong in this taskgroup.  */
494   struct priority_queue taskgroup_queue;
495   uintptr_t *reductions;
496   bool in_taskgroup_wait;
497   bool cancelled;
498   bool workshare;
499   gomp_sem_t taskgroup_sem;
500   size_t num_children;
501 };
502 
503 /* Various state of OpenMP async offloading tasks.  */
504 enum gomp_target_task_state
505 {
506   GOMP_TARGET_TASK_DATA,
507   GOMP_TARGET_TASK_BEFORE_MAP,
508   GOMP_TARGET_TASK_FALLBACK,
509   GOMP_TARGET_TASK_READY_TO_RUN,
510   GOMP_TARGET_TASK_RUNNING,
511   GOMP_TARGET_TASK_FINISHED
512 };
513 
514 /* This structure describes a target task.  */
515 
516 struct gomp_target_task
517 {
518   struct gomp_device_descr *devicep;
519   void (*fn) (void *);
520   size_t mapnum;
521   size_t *sizes;
522   unsigned short *kinds;
523   unsigned int flags;
524   enum gomp_target_task_state state;
525   struct target_mem_desc *tgt;
526   struct gomp_task *task;
527   struct gomp_team *team;
528   /* Device-specific target arguments.  */
529   void **args;
530   void *hostaddrs[];
531 };
532 
533 /* This structure describes a "team" of threads.  These are the threads
534    that are spawned by a PARALLEL constructs, as well as the work sharing
535    constructs that the team encounters.  */
536 
537 struct gomp_team
538 {
539   /* This is the number of threads in the current team.  */
540   unsigned nthreads;
541 
542   /* This is number of gomp_work_share structs that have been allocated
543      as a block last time.  */
544   unsigned work_share_chunk;
545 
546   /* This is the saved team state that applied to a master thread before
547      the current thread was created.  */
548   struct gomp_team_state prev_ts;
549 
550   /* This semaphore should be used by the master thread instead of its
551      "native" semaphore in the thread structure.  Required for nested
552      parallels, as the master is a member of two teams.  */
553   gomp_sem_t master_release;
554 
555   /* This points to an array with pointers to the release semaphore
556      of the threads in the team.  */
557   gomp_sem_t **ordered_release;
558 
559   /* List of work shares on which gomp_fini_work_share hasn't been
560      called yet.  If the team hasn't been cancelled, this should be
561      equal to each thr->ts.work_share, but otherwise it can be a possibly
562      long list of workshares.  */
563   struct gomp_work_share *work_shares_to_free;
564 
565   /* List of gomp_work_share structs chained through next_free fields.
566      This is populated and taken off only by the first thread in the
567      team encountering a new work sharing construct, in a critical
568      section.  */
569   struct gomp_work_share *work_share_list_alloc;
570 
571   /* List of gomp_work_share structs freed by free_work_share.  New
572      entries are atomically added to the start of the list, and
573      alloc_work_share can safely only move all but the first entry
574      to work_share_list alloc, as free_work_share can happen concurrently
575      with alloc_work_share.  */
576   struct gomp_work_share *work_share_list_free;
577 
578 #ifdef HAVE_SYNC_BUILTINS
579   /* Number of simple single regions encountered by threads in this
580      team.  */
581   unsigned long single_count;
582 #else
583   /* Mutex protecting addition of workshares to work_share_list_free.  */
584   gomp_mutex_t work_share_list_free_lock;
585 #endif
586 
587   /* This barrier is used for most synchronization of the team.  */
588   gomp_barrier_t barrier;
589 
590   /* Initial work shares, to avoid allocating any gomp_work_share
591      structs in the common case.  */
592   struct gomp_work_share work_shares[8];
593 
594   gomp_mutex_t task_lock;
595   /* Scheduled tasks.  */
596   struct priority_queue task_queue;
597   /* Number of all GOMP_TASK_{WAITING,TIED} tasks in the team.  */
598   unsigned int task_count;
599   /* Number of GOMP_TASK_WAITING tasks currently waiting to be scheduled.  */
600   unsigned int task_queued_count;
601   /* Number of GOMP_TASK_{WAITING,TIED} tasks currently running
602      directly in gomp_barrier_handle_tasks; tasks spawned
603      from e.g. GOMP_taskwait or GOMP_taskgroup_end don't count, even when
604      that is called from a task run from gomp_barrier_handle_tasks.
605      task_running_count should be always <= team->nthreads,
606      and if current task isn't in_tied_task, then it will be
607      even < team->nthreads.  */
608   unsigned int task_running_count;
609   int work_share_cancelled;
610   int team_cancelled;
611 
612   /* This array contains structures for implicit tasks.  */
613   struct gomp_task implicit_task[];
614 };
615 
616 /* This structure contains all data that is private to libgomp and is
617    allocated per thread.  */
618 
619 struct gomp_thread
620 {
621   /* This is the function that the thread should run upon launch.  */
622   void (*fn) (void *data);
623   void *data;
624 
625   /* This is the current team state for this thread.  The ts.team member
626      is NULL only if the thread is idle.  */
627   struct gomp_team_state ts;
628 
629   /* This is the task that the thread is currently executing.  */
630   struct gomp_task *task;
631 
632   /* This semaphore is used for ordered loops.  */
633   gomp_sem_t release;
634 
635   /* Place this thread is bound to plus one, or zero if not bound
636      to any place.  */
637   unsigned int place;
638 
639   /* User pthread thread pool */
640   struct gomp_thread_pool *thread_pool;
641 
642 #if defined(LIBGOMP_USE_PTHREADS) \
643     && (!defined(HAVE_TLS) \
644 	|| !defined(__GLIBC__) \
645 	|| !defined(USING_INITIAL_EXEC_TLS))
646   /* pthread_t of the thread containing this gomp_thread.
647      On Linux when using initial-exec TLS,
648      (typeof (pthread_t)) gomp_thread () - pthread_self ()
649      is constant in all threads, so we can optimize and not
650      store it.  */
651 #define GOMP_NEEDS_THREAD_HANDLE 1
652   pthread_t handle;
653 #endif
654 };
655 
656 
657 struct gomp_thread_pool
658 {
659   /* This array manages threads spawned from the top level, which will
660      return to the idle loop once the current PARALLEL construct ends.  */
661   struct gomp_thread **threads;
662   unsigned threads_size;
663   unsigned threads_used;
664   /* The last team is used for non-nested teams to delay their destruction to
665      make sure all the threads in the team move on to the pool's barrier before
666      the team's barrier is destroyed.  */
667   struct gomp_team *last_team;
668   /* Number of threads running in this contention group.  */
669   unsigned long threads_busy;
670 
671   /* This barrier holds and releases threads waiting in thread pools.  */
672   gomp_simple_barrier_t threads_dock;
673 };
674 
675 enum gomp_cancel_kind
676 {
677   GOMP_CANCEL_PARALLEL = 1,
678   GOMP_CANCEL_LOOP = 2,
679   GOMP_CANCEL_FOR = GOMP_CANCEL_LOOP,
680   GOMP_CANCEL_DO = GOMP_CANCEL_LOOP,
681   GOMP_CANCEL_SECTIONS = 4,
682   GOMP_CANCEL_TASKGROUP = 8
683 };
684 
685 /* ... and here is that TLS data.  */
686 
687 #if defined __nvptx__
688 extern struct gomp_thread *nvptx_thrs __attribute__((shared));
gomp_thread(void)689 static inline struct gomp_thread *gomp_thread (void)
690 {
691   int tid;
692   asm ("mov.u32 %0, %%tid.y;" : "=r" (tid));
693   return nvptx_thrs + tid;
694 }
695 #elif defined HAVE_TLS || defined USE_EMUTLS
696 extern __thread struct gomp_thread gomp_tls_data;
gomp_thread(void)697 static inline struct gomp_thread *gomp_thread (void)
698 {
699   return &gomp_tls_data;
700 }
701 #else
702 extern pthread_key_t gomp_tls_key;
gomp_thread(void)703 static inline struct gomp_thread *gomp_thread (void)
704 {
705   return pthread_getspecific (gomp_tls_key);
706 }
707 #endif
708 
709 extern struct gomp_task_icv *gomp_new_icv (void);
710 
711 /* Here's how to access the current copy of the ICVs.  */
712 
gomp_icv(bool write)713 static inline struct gomp_task_icv *gomp_icv (bool write)
714 {
715   struct gomp_task *task = gomp_thread ()->task;
716   if (task)
717     return &task->icv;
718   else if (write)
719     return gomp_new_icv ();
720   else
721     return &gomp_global_icv;
722 }
723 
724 #ifdef LIBGOMP_USE_PTHREADS
725 /* The attributes to be used during thread creation.  */
726 extern pthread_attr_t gomp_thread_attr;
727 
728 extern pthread_key_t gomp_thread_destructor;
729 #endif
730 
731 /* Function prototypes.  */
732 
733 /* affinity.c */
734 
735 extern void gomp_init_affinity (void);
736 #ifdef LIBGOMP_USE_PTHREADS
737 extern void gomp_init_thread_affinity (pthread_attr_t *, unsigned int);
738 #endif
739 extern void **gomp_affinity_alloc (unsigned long, bool);
740 extern void gomp_affinity_init_place (void *);
741 extern bool gomp_affinity_add_cpus (void *, unsigned long, unsigned long,
742 				    long, bool);
743 extern bool gomp_affinity_remove_cpu (void *, unsigned long);
744 extern bool gomp_affinity_copy_place (void *, void *, long);
745 extern bool gomp_affinity_same_place (void *, void *);
746 extern bool gomp_affinity_finalize_place_list (bool);
747 extern bool gomp_affinity_init_level (int, unsigned long, bool);
748 extern void gomp_affinity_print_place (void *);
749 extern void gomp_get_place_proc_ids_8 (int, int64_t *);
750 extern void gomp_display_affinity_place (char *, size_t, size_t *, int);
751 
752 /* affinity-fmt.c */
753 
754 extern void gomp_print_string (const char *str, size_t len);
755 extern void gomp_set_affinity_format (const char *, size_t);
756 extern void gomp_display_string (char *, size_t, size_t *, const char *,
757 				 size_t);
758 #ifdef LIBGOMP_USE_PTHREADS
759 typedef pthread_t gomp_thread_handle;
760 #else
761 typedef struct {} gomp_thread_handle;
762 #endif
763 extern size_t gomp_display_affinity (char *, size_t, const char *,
764 				     gomp_thread_handle,
765 				     struct gomp_team_state *, unsigned int);
766 extern void gomp_display_affinity_thread (gomp_thread_handle,
767 					  struct gomp_team_state *,
768 					  unsigned int) __attribute__((cold));
769 
770 /* iter.c */
771 
772 extern int gomp_iter_static_next (long *, long *);
773 extern bool gomp_iter_dynamic_next_locked (long *, long *);
774 extern bool gomp_iter_guided_next_locked (long *, long *);
775 
776 #ifdef HAVE_SYNC_BUILTINS
777 extern bool gomp_iter_dynamic_next (long *, long *);
778 extern bool gomp_iter_guided_next (long *, long *);
779 #endif
780 
781 /* iter_ull.c */
782 
783 extern int gomp_iter_ull_static_next (unsigned long long *,
784 				      unsigned long long *);
785 extern bool gomp_iter_ull_dynamic_next_locked (unsigned long long *,
786 					       unsigned long long *);
787 extern bool gomp_iter_ull_guided_next_locked (unsigned long long *,
788 					      unsigned long long *);
789 
790 #if defined HAVE_SYNC_BUILTINS && defined __LP64__
791 extern bool gomp_iter_ull_dynamic_next (unsigned long long *,
792 					unsigned long long *);
793 extern bool gomp_iter_ull_guided_next (unsigned long long *,
794 				       unsigned long long *);
795 #endif
796 
797 /* ordered.c */
798 
799 extern void gomp_ordered_first (void);
800 extern void gomp_ordered_last (void);
801 extern void gomp_ordered_next (void);
802 extern void gomp_ordered_static_init (void);
803 extern void gomp_ordered_static_next (void);
804 extern void gomp_ordered_sync (void);
805 extern void gomp_doacross_init (unsigned, long *, long, size_t);
806 extern void gomp_doacross_ull_init (unsigned, unsigned long long *,
807 				    unsigned long long, size_t);
808 
809 /* parallel.c */
810 
811 extern unsigned gomp_resolve_num_threads (unsigned, unsigned);
812 
813 /* proc.c (in config/) */
814 
815 extern void gomp_init_num_threads (void);
816 extern unsigned gomp_dynamic_max_threads (void);
817 
818 /* task.c */
819 
820 extern void gomp_init_task (struct gomp_task *, struct gomp_task *,
821 			    struct gomp_task_icv *);
822 extern void gomp_end_task (void);
823 extern void gomp_barrier_handle_tasks (gomp_barrier_state_t);
824 extern void gomp_task_maybe_wait_for_dependencies (void **);
825 extern bool gomp_create_target_task (struct gomp_device_descr *,
826 				     void (*) (void *), size_t, void **,
827 				     size_t *, unsigned short *, unsigned int,
828 				     void **, void **,
829 				     enum gomp_target_task_state);
830 extern struct gomp_taskgroup *gomp_parallel_reduction_register (uintptr_t *,
831 								unsigned);
832 extern void gomp_workshare_taskgroup_start (void);
833 extern void gomp_workshare_task_reduction_register (uintptr_t *, uintptr_t *);
834 
835 static void inline
gomp_finish_task(struct gomp_task * task)836 gomp_finish_task (struct gomp_task *task)
837 {
838   if (__builtin_expect (task->depend_hash != NULL, 0))
839     free (task->depend_hash);
840 }
841 
842 /* team.c */
843 
844 extern struct gomp_team *gomp_new_team (unsigned);
845 extern void gomp_team_start (void (*) (void *), void *, unsigned,
846 			     unsigned, struct gomp_team *,
847 			     struct gomp_taskgroup *);
848 extern void gomp_team_end (void);
849 extern void gomp_free_thread (void *);
850 extern int gomp_pause_host (void);
851 
852 /* target.c */
853 
854 extern void gomp_init_targets_once (void);
855 extern int gomp_get_num_devices (void);
856 extern bool gomp_target_task_fn (void *);
857 
858 /* Splay tree definitions.  */
859 typedef struct splay_tree_node_s *splay_tree_node;
860 typedef struct splay_tree_s *splay_tree;
861 typedef struct splay_tree_key_s *splay_tree_key;
862 
863 struct target_var_desc {
864   /* Splay key.  */
865   splay_tree_key key;
866   /* True if data should be copied from device to host at the end.  */
867   bool copy_from;
868   /* True if data always should be copied from device to host at the end.  */
869   bool always_copy_from;
870   /* Relative offset against key host_start.  */
871   uintptr_t offset;
872   /* Actual length.  */
873   uintptr_t length;
874 };
875 
876 struct target_mem_desc {
877   /* Reference count.  */
878   uintptr_t refcount;
879   /* All the splay nodes allocated together.  */
880   splay_tree_node array;
881   /* Start of the target region.  */
882   uintptr_t tgt_start;
883   /* End of the targer region.  */
884   uintptr_t tgt_end;
885   /* Handle to free.  */
886   void *to_free;
887   /* Previous target_mem_desc.  */
888   struct target_mem_desc *prev;
889   /* Number of items in following list.  */
890   size_t list_count;
891 
892   /* Corresponding target device descriptor.  */
893   struct gomp_device_descr *device_descr;
894 
895   /* List of target items to remove (or decrease refcount)
896      at the end of region.  */
897   struct target_var_desc list[];
898 };
899 
900 /* Special value for refcount - infinity.  */
901 #define REFCOUNT_INFINITY (~(uintptr_t) 0)
902 /* Special value for refcount - tgt_offset contains target address of the
903    artificial pointer to "omp declare target link" object.  */
904 #define REFCOUNT_LINK (~(uintptr_t) 1)
905 
906 struct splay_tree_key_s {
907   /* Address of the host object.  */
908   uintptr_t host_start;
909   /* Address immediately after the host object.  */
910   uintptr_t host_end;
911   /* Descriptor of the target memory.  */
912   struct target_mem_desc *tgt;
913   /* Offset from tgt->tgt_start to the start of the target object.  */
914   uintptr_t tgt_offset;
915   /* Reference count.  */
916   uintptr_t refcount;
917   /* Dynamic reference count.  */
918   uintptr_t dynamic_refcount;
919   /* Pointer to the original mapping of "omp declare target link" object.  */
920   splay_tree_key link_key;
921 };
922 
923 /* The comparison function.  */
924 
925 static inline int
splay_compare(splay_tree_key x,splay_tree_key y)926 splay_compare (splay_tree_key x, splay_tree_key y)
927 {
928   if (x->host_start == x->host_end
929       && y->host_start == y->host_end)
930     return 0;
931   if (x->host_end <= y->host_start)
932     return -1;
933   if (x->host_start >= y->host_end)
934     return 1;
935   return 0;
936 }
937 
938 #include "splay-tree.h"
939 
940 typedef struct acc_dispatch_t
941 {
942   /* This is a linked list of data mapped using the
943      acc_map_data/acc_unmap_data or "acc enter data"/"acc exit data" pragmas.
944      Unlike mapped_data in the goacc_thread struct, unmapping can
945      happen out-of-order with respect to mapping.  */
946   /* This is guarded by the lock in the "outer" struct gomp_device_descr.  */
947   struct target_mem_desc *data_environ;
948 
949   /* Execute.  */
950   __typeof (GOMP_OFFLOAD_openacc_exec) *exec_func;
951 
952   /* Async cleanup callback registration.  */
953   __typeof (GOMP_OFFLOAD_openacc_register_async_cleanup)
954     *register_async_cleanup_func;
955 
956   /* Asynchronous routines.  */
957   __typeof (GOMP_OFFLOAD_openacc_async_test) *async_test_func;
958   __typeof (GOMP_OFFLOAD_openacc_async_test_all) *async_test_all_func;
959   __typeof (GOMP_OFFLOAD_openacc_async_wait) *async_wait_func;
960   __typeof (GOMP_OFFLOAD_openacc_async_wait_async) *async_wait_async_func;
961   __typeof (GOMP_OFFLOAD_openacc_async_wait_all) *async_wait_all_func;
962   __typeof (GOMP_OFFLOAD_openacc_async_wait_all_async)
963     *async_wait_all_async_func;
964   __typeof (GOMP_OFFLOAD_openacc_async_set_async) *async_set_async_func;
965 
966   /* Create/destroy TLS data.  */
967   __typeof (GOMP_OFFLOAD_openacc_create_thread_data) *create_thread_data_func;
968   __typeof (GOMP_OFFLOAD_openacc_destroy_thread_data)
969     *destroy_thread_data_func;
970 
971   /* NVIDIA target specific routines.  */
972   struct {
973     __typeof (GOMP_OFFLOAD_openacc_cuda_get_current_device)
974       *get_current_device_func;
975     __typeof (GOMP_OFFLOAD_openacc_cuda_get_current_context)
976       *get_current_context_func;
977     __typeof (GOMP_OFFLOAD_openacc_cuda_get_stream) *get_stream_func;
978     __typeof (GOMP_OFFLOAD_openacc_cuda_set_stream) *set_stream_func;
979   } cuda;
980 } acc_dispatch_t;
981 
982 /* Various state of the accelerator device.  */
983 enum gomp_device_state
984 {
985   GOMP_DEVICE_UNINITIALIZED,
986   GOMP_DEVICE_INITIALIZED,
987   GOMP_DEVICE_FINALIZED
988 };
989 
990 /* This structure describes accelerator device.
991    It contains name of the corresponding libgomp plugin, function handlers for
992    interaction with the device, ID-number of the device, and information about
993    mapped memory.  */
994 struct gomp_device_descr
995 {
996   /* Immutable data, which is only set during initialization, and which is not
997      guarded by the lock.  */
998 
999   /* The name of the device.  */
1000   const char *name;
1001 
1002   /* Capabilities of device (supports OpenACC, OpenMP).  */
1003   unsigned int capabilities;
1004 
1005   /* This is the ID number of device among devices of the same type.  */
1006   int target_id;
1007 
1008   /* This is the TYPE of device.  */
1009   enum offload_target_type type;
1010 
1011   /* Function handlers.  */
1012   __typeof (GOMP_OFFLOAD_get_name) *get_name_func;
1013   __typeof (GOMP_OFFLOAD_get_caps) *get_caps_func;
1014   __typeof (GOMP_OFFLOAD_get_type) *get_type_func;
1015   __typeof (GOMP_OFFLOAD_get_num_devices) *get_num_devices_func;
1016   __typeof (GOMP_OFFLOAD_init_device) *init_device_func;
1017   __typeof (GOMP_OFFLOAD_fini_device) *fini_device_func;
1018   __typeof (GOMP_OFFLOAD_version) *version_func;
1019   __typeof (GOMP_OFFLOAD_load_image) *load_image_func;
1020   __typeof (GOMP_OFFLOAD_unload_image) *unload_image_func;
1021   __typeof (GOMP_OFFLOAD_alloc) *alloc_func;
1022   __typeof (GOMP_OFFLOAD_free) *free_func;
1023   __typeof (GOMP_OFFLOAD_dev2host) *dev2host_func;
1024   __typeof (GOMP_OFFLOAD_host2dev) *host2dev_func;
1025   __typeof (GOMP_OFFLOAD_dev2dev) *dev2dev_func;
1026   __typeof (GOMP_OFFLOAD_can_run) *can_run_func;
1027   __typeof (GOMP_OFFLOAD_run) *run_func;
1028   __typeof (GOMP_OFFLOAD_async_run) *async_run_func;
1029 
1030   /* Splay tree containing information about mapped memory regions.  */
1031   struct splay_tree_s mem_map;
1032 
1033   /* Mutex for the mutable data.  */
1034   gomp_mutex_t lock;
1035 
1036   /* Current state of the device.  OpenACC allows to move from INITIALIZED state
1037      back to UNINITIALIZED state.  OpenMP allows only to move from INITIALIZED
1038      to FINALIZED state (at program shutdown).  */
1039   enum gomp_device_state state;
1040 
1041   /* OpenACC-specific data and functions.  */
1042   /* This is mutable because of its mutable data_environ and target_data
1043      members.  */
1044   acc_dispatch_t openacc;
1045 };
1046 
1047 /* Kind of the pragma, for which gomp_map_vars () is called.  */
1048 enum gomp_map_vars_kind
1049 {
1050   GOMP_MAP_VARS_OPENACC,
1051   GOMP_MAP_VARS_TARGET,
1052   GOMP_MAP_VARS_DATA,
1053   GOMP_MAP_VARS_ENTER_DATA
1054 };
1055 
1056 extern void gomp_acc_insert_pointer (size_t, void **, size_t *, void *);
1057 extern void gomp_acc_remove_pointer (void *, size_t, bool, int, int, int);
1058 extern void gomp_acc_declare_allocate (bool, size_t, void **, size_t *,
1059 				       unsigned short *);
1060 
1061 extern struct target_mem_desc *gomp_map_vars (struct gomp_device_descr *,
1062 					      size_t, void **, void **,
1063 					      size_t *, void *, bool,
1064 					      enum gomp_map_vars_kind);
1065 extern void gomp_unmap_vars (struct target_mem_desc *, bool);
1066 extern void gomp_init_device (struct gomp_device_descr *);
1067 extern void gomp_free_memmap (struct splay_tree_s *);
1068 extern void gomp_unload_device (struct gomp_device_descr *);
1069 extern bool gomp_remove_var (struct gomp_device_descr *, splay_tree_key);
1070 
1071 /* work.c */
1072 
1073 extern void gomp_init_work_share (struct gomp_work_share *, size_t, unsigned);
1074 extern void gomp_fini_work_share (struct gomp_work_share *);
1075 extern bool gomp_work_share_start (size_t);
1076 extern void gomp_work_share_end (void);
1077 extern bool gomp_work_share_end_cancel (void);
1078 extern void gomp_work_share_end_nowait (void);
1079 
1080 static inline void
gomp_work_share_init_done(void)1081 gomp_work_share_init_done (void)
1082 {
1083   struct gomp_thread *thr = gomp_thread ();
1084   if (__builtin_expect (thr->ts.last_work_share != NULL, 1))
1085     gomp_ptrlock_set (&thr->ts.last_work_share->next_ws, thr->ts.work_share);
1086 }
1087 
1088 #ifdef HAVE_ATTRIBUTE_VISIBILITY
1089 # pragma GCC visibility pop
1090 #endif
1091 
1092 /* Now that we're back to default visibility, include the globals.  */
1093 #include "libgomp_g.h"
1094 
1095 /* Include omp.h by parts.  */
1096 #include "omp-lock.h"
1097 #define _LIBGOMP_OMP_LOCK_DEFINED 1
1098 #include "omp.h.in"
1099 
1100 #if !defined (HAVE_ATTRIBUTE_VISIBILITY) \
1101     || !defined (HAVE_ATTRIBUTE_ALIAS) \
1102     || !defined (HAVE_AS_SYMVER_DIRECTIVE) \
1103     || !defined (PIC) \
1104     || !defined (HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
1105 # undef LIBGOMP_GNU_SYMBOL_VERSIONING
1106 #endif
1107 
1108 #ifdef LIBGOMP_GNU_SYMBOL_VERSIONING
1109 extern void gomp_init_lock_30 (omp_lock_t *) __GOMP_NOTHROW;
1110 extern void gomp_destroy_lock_30 (omp_lock_t *) __GOMP_NOTHROW;
1111 extern void gomp_set_lock_30 (omp_lock_t *) __GOMP_NOTHROW;
1112 extern void gomp_unset_lock_30 (omp_lock_t *) __GOMP_NOTHROW;
1113 extern int gomp_test_lock_30 (omp_lock_t *) __GOMP_NOTHROW;
1114 extern void gomp_init_nest_lock_30 (omp_nest_lock_t *) __GOMP_NOTHROW;
1115 extern void gomp_destroy_nest_lock_30 (omp_nest_lock_t *) __GOMP_NOTHROW;
1116 extern void gomp_set_nest_lock_30 (omp_nest_lock_t *) __GOMP_NOTHROW;
1117 extern void gomp_unset_nest_lock_30 (omp_nest_lock_t *) __GOMP_NOTHROW;
1118 extern int gomp_test_nest_lock_30 (omp_nest_lock_t *) __GOMP_NOTHROW;
1119 
1120 extern void gomp_init_lock_25 (omp_lock_25_t *) __GOMP_NOTHROW;
1121 extern void gomp_destroy_lock_25 (omp_lock_25_t *) __GOMP_NOTHROW;
1122 extern void gomp_set_lock_25 (omp_lock_25_t *) __GOMP_NOTHROW;
1123 extern void gomp_unset_lock_25 (omp_lock_25_t *) __GOMP_NOTHROW;
1124 extern int gomp_test_lock_25 (omp_lock_25_t *) __GOMP_NOTHROW;
1125 extern void gomp_init_nest_lock_25 (omp_nest_lock_25_t *) __GOMP_NOTHROW;
1126 extern void gomp_destroy_nest_lock_25 (omp_nest_lock_25_t *) __GOMP_NOTHROW;
1127 extern void gomp_set_nest_lock_25 (omp_nest_lock_25_t *) __GOMP_NOTHROW;
1128 extern void gomp_unset_nest_lock_25 (omp_nest_lock_25_t *) __GOMP_NOTHROW;
1129 extern int gomp_test_nest_lock_25 (omp_nest_lock_25_t *) __GOMP_NOTHROW;
1130 
1131 # define omp_lock_symver(fn) \
1132   __asm (".symver g" #fn "_30, " #fn "@@OMP_3.0"); \
1133   __asm (".symver g" #fn "_25, " #fn "@OMP_1.0");
1134 #else
1135 # define gomp_init_lock_30 omp_init_lock
1136 # define gomp_destroy_lock_30 omp_destroy_lock
1137 # define gomp_set_lock_30 omp_set_lock
1138 # define gomp_unset_lock_30 omp_unset_lock
1139 # define gomp_test_lock_30 omp_test_lock
1140 # define gomp_init_nest_lock_30 omp_init_nest_lock
1141 # define gomp_destroy_nest_lock_30 omp_destroy_nest_lock
1142 # define gomp_set_nest_lock_30 omp_set_nest_lock
1143 # define gomp_unset_nest_lock_30 omp_unset_nest_lock
1144 # define gomp_test_nest_lock_30 omp_test_nest_lock
1145 #endif
1146 
1147 #ifdef HAVE_ATTRIBUTE_VISIBILITY
1148 # define attribute_hidden __attribute__ ((visibility ("hidden")))
1149 #else
1150 # define attribute_hidden
1151 #endif
1152 
1153 #if __GNUC__ >= 9
1154 #  define HAVE_ATTRIBUTE_COPY
1155 #endif
1156 
1157 #ifdef HAVE_ATTRIBUTE_COPY
1158 # define attribute_copy(arg) __attribute__ ((copy (arg)))
1159 #else
1160 # define attribute_copy(arg)
1161 #endif
1162 
1163 #ifdef HAVE_ATTRIBUTE_ALIAS
1164 # define strong_alias(fn, al) \
1165   extern __typeof (fn) al __attribute__ ((alias (#fn))) attribute_copy (fn);
1166 
1167 # define ialias_ulp	ialias_str1(__USER_LABEL_PREFIX__)
1168 # define ialias_str1(x)	ialias_str2(x)
1169 # define ialias_str2(x)	#x
1170 # define ialias(fn) \
1171   extern __typeof (fn) gomp_ialias_##fn \
1172     __attribute__ ((alias (#fn))) attribute_hidden attribute_copy (fn);
1173 # define ialias_redirect(fn) \
1174   extern __typeof (fn) fn __asm__ (ialias_ulp "gomp_ialias_" #fn) attribute_hidden;
1175 # define ialias_call(fn) gomp_ialias_ ## fn
1176 #else
1177 # define ialias(fn)
1178 # define ialias_redirect(fn)
1179 # define ialias_call(fn) fn
1180 #endif
1181 
1182 /* Helper function for priority_node_to_task() and
1183    task_to_priority_node().
1184 
1185    Return the offset from a task to its priority_node entry.  The
1186    priority_node entry is has a type of TYPE.  */
1187 
1188 static inline size_t
priority_queue_offset(enum priority_queue_type type)1189 priority_queue_offset (enum priority_queue_type type)
1190 {
1191   return offsetof (struct gomp_task, pnode[(int) type]);
1192 }
1193 
1194 /* Return the task associated with a priority NODE of type TYPE.  */
1195 
1196 static inline struct gomp_task *
priority_node_to_task(enum priority_queue_type type,struct priority_node * node)1197 priority_node_to_task (enum priority_queue_type type,
1198 		       struct priority_node *node)
1199 {
1200   return (struct gomp_task *) ((char *) node - priority_queue_offset (type));
1201 }
1202 
1203 /* Return the priority node of type TYPE for a given TASK.  */
1204 
1205 static inline struct priority_node *
task_to_priority_node(enum priority_queue_type type,struct gomp_task * task)1206 task_to_priority_node (enum priority_queue_type type,
1207 		       struct gomp_task *task)
1208 {
1209   return (struct priority_node *) ((char *) task
1210 				   + priority_queue_offset (type));
1211 }
1212 
1213 #ifdef LIBGOMP_USE_PTHREADS
1214 static inline gomp_thread_handle
gomp_thread_self(void)1215 gomp_thread_self (void)
1216 {
1217   return pthread_self ();
1218 }
1219 
1220 static inline gomp_thread_handle
gomp_thread_to_pthread_t(struct gomp_thread * thr)1221 gomp_thread_to_pthread_t (struct gomp_thread *thr)
1222 {
1223   struct gomp_thread *this_thr = gomp_thread ();
1224   if (thr == this_thr)
1225     return pthread_self ();
1226 #ifdef GOMP_NEEDS_THREAD_HANDLE
1227   return thr->handle;
1228 #else
1229   /* On Linux with initial-exec TLS, the pthread_t of the thread containing
1230      thr can be computed from thr, this_thr and pthread_self (),
1231      as the distance between this_thr and pthread_self () is constant.  */
1232   return pthread_self () + ((uintptr_t) thr - (uintptr_t) this_thr);
1233 #endif
1234 }
1235 #else
1236 static inline gomp_thread_handle
gomp_thread_self(void)1237 gomp_thread_self (void)
1238 {
1239   return (gomp_thread_handle) {};
1240 }
1241 
1242 static inline gomp_thread_handle
gomp_thread_to_pthread_t(struct gomp_thread * thr)1243 gomp_thread_to_pthread_t (struct gomp_thread *thr)
1244 {
1245   (void) thr;
1246   return gomp_thread_self ();
1247 }
1248 #endif
1249 
1250 #endif /* LIBGOMP_H */
1251