[OMPT] Frame information for openmp taskwait

[protze.joachim]

Summary

For pragma openmp taskwait the runtime is called from the task context. Therefore, the reentry frame information should be updated.
The information should be available for both taskwait event calls; therefore, set before the first event and reset after the last event.

[Hahnfeld]

LGTM

[jmellorcrummey]

LGTM.

runtime/src/kmp_tasking.c

#if OMPT_SUPPORT && OMPT_TRACE
         ompt_task_id_t my_task_id;
         ompt_parallel_id_t my_parallel_id;
         
         if (ompt_enabled) {
             kmp_team_t *team = thread->th.th_team;
             my_task_id = taskdata->ompt_task_info.task_id;
             my_parallel_id = team->t.ompt_team_info.parallel_id;
             
+            taskdata->ompt_task_info.frame.reenter_runtime_frame = __builtin_frame_address(0);
             if (ompt_callbacks.ompt_callback(ompt_event_taskwait_begin)) {
                 ompt_callbacks.ompt_callback(ompt_event_taskwait_begin)(
                                 my_parallel_id, my_task_id);
             }
         }
 #endif
 
 #if USE_ITT_BUILD
#if USE_ITT_BUILD
         if ( itt_sync_obj != NULL )
             __kmp_itt_taskwait_finished( gtid, itt_sync_obj );
 #endif /* USE_ITT_BUILD */
 
         // GEH TODO: shouldn't we have some sort of OMPRAP API calls here to mark end of wait?
         taskdata->td_taskwait_thread = - taskdata->td_taskwait_thread;
 
 #if OMPT_SUPPORT && OMPT_TRACE
-        if (ompt_enabled &&
-            ompt_callbacks.ompt_callback(ompt_event_taskwait_end)) {
+        if (ompt_enabled)
+        {
+            if(ompt_callbacks.ompt_callback(ompt_event_taskwait_end)) {
                 ompt_callbacks.ompt_callback(ompt_event_taskwait_end)(
                                 my_parallel_id, my_task_id);
             }
+            taskdata->ompt_task_info.frame.reenter_runtime_frame = 0;
+        }
 #endif
     }
 
     KA_TRACE(10, ("__kmpc_omp_taskwait(exit): T#%d task %p finished waiting, "
                   "returning TASK_CURRENT_NOT_QUEUED\n", gtid, taskdata) );
 
     return TASK_CURRENT_NOT_QUEUED;
 }