[Openmp-commits] [PATCH] D23116: Do not block on explicit task depending on proxy task

[Jonas Hahnfeld via Openmp-commits]

Hahnfeld created this revision.
Hahnfeld added reviewers: jlpeyton, AndreyChurbanov.
Hahnfeld added a subscriber: openmp-commits.

Consider the following code:

```
int dep;
#pragma omp target nowait depend(out: dep)
{
    sleep(1);
}
#pragma omp task depend(in: dep)
{
    printf("Task with dependency\n");
}
printf("Doing some work...\n");
```

In its current state the runtime will block on the second task and not
continue execution.

https://reviews.llvm.org/D23116

Files:
  runtime/src/kmp_taskdeps.cpp

Index: runtime/src/kmp_taskdeps.cpp
===================================================================
--- runtime/src/kmp_taskdeps.cpp
+++ runtime/src/kmp_taskdeps.cpp
@@ -480,7 +480,8 @@
 
     bool serial = current_task->td_flags.team_serial || current_task->td_flags.tasking_ser || current_task->td_flags.final;
 #if OMP_45_ENABLED
-    serial = serial && !(new_taskdata->td_flags.proxy == TASK_PROXY);
+    kmp_task_team_t * task_team = thread->th.th_task_team;
+    serial = serial && !(task_team && task_team->tt.tt_found_proxy_tasks);
 #endif
 
     if ( !serial && ( ndeps > 0 || ndeps_noalias > 0 )) {
@@ -505,14 +506,8 @@
             return TASK_CURRENT_NOT_QUEUED;
         }
     } else {
-#if OMP_45_ENABLED
-        kmp_task_team_t * task_team = thread->th.th_task_team;
-        if ( task_team && task_team->tt.tt_found_proxy_tasks )
-           __kmpc_omp_wait_deps ( loc_ref, gtid, ndeps, dep_list, ndeps_noalias, noalias_dep_list );
-        else
-#endif
-           KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d ignored dependencies for task (serialized)"
-                           "loc=%p task=%p\n", gtid, loc_ref, new_taskdata ) );
+        KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d ignored dependencies for task (serialized)"
+                      "loc=%p task=%p\n", gtid, loc_ref, new_taskdata ) );
     }
 
     KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d task had no blocking dependencies : "


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