openmp/runtime/test/tasking/detach_nested_task.c

   1 // RUN: %libomp-compile-and-run
   2
   3 // Checked gcc 10.1 still does not support detach clause on task construct.
   4 // UNSUPPORTED: gcc-4, gcc-5, gcc-6, gcc-7, gcc-8, gcc-9, gcc-10
   5 // gcc 11 introduced detach clause, but gomp interface in libomp has no support
   6 // XFAIL: gcc-11, gcc-12
   7 // clang supports detach clause since version 11.
   8 // UNSUPPORTED: clang-10, clang-9, clang-8, clang-7
   9 // icc compiler does not support detach clause.
  10 // UNSUPPORTED: icc
  11
  12 // The outer detachable task creates multiple child tasks with dependencies
  13 // when the last inner task incremented ret, the task calls omp_fulfill_event
  14 // to release the outer task.
  15
  16 #include <omp.h>
  17 #include <stdio.h>
  18 #include "omp_my_sleep.h"
  19
  20 int *buf;
  21
  22 int foo(int n)
  23 {
  24   int ret = 0;
  25   for (int i = 0; i < n; ++i) {
  26     omp_event_handle_t event;
  27     #pragma omp task detach(event) firstprivate(i,n) shared(ret)
  28     {
  29       for (int j = 0; j < n; ++j) {
  30         #pragma omp task firstprivate(event,i,j,n) shared(ret) default(none) depend(out:ret)
  31         {
  32           //printf("Task %i, %i: %i\n", i, j, omp_get_thread_num());
  33           my_sleep(.01);
  34           #pragma omp atomic
  35             ret++;
  36 #if _OPENMP
  37           if (j == n-1) {
  38             //printf("Task %i, %i: omp_fulfill_event()\n", i, j);
  39             omp_fulfill_event(event);
  40           }
  41 #endif
  42         }
  43       }
  44     }
  45   }
  46   // the taskwait only guarantees the outer tasks to complete.
  47   #pragma omp taskwait
  48
  49   return ret;
  50 }
  51
  52
  53 int main()
  54 {
  55   int ret;
  56 #pragma omp parallel num_threads(4)
  57 #pragma omp master
  58   {
  59     ret = foo(8);
  60   }
  61   printf("%i\n", ret);
  62   return !(ret == 64);
  63 }