openmp/runtime/test/parallel/omp_nested.c

   1 // RUN: %libomp-compile-and-run
   2 #include <stdio.h>
   3 #include "omp_testsuite.h"
   4
   5 /*
   6  * Test if the compiler supports nested parallelism
   7  * By Chunhua Liao, University of Houston
   8  * Oct. 2005
   9  */
  10 int test_omp_nested()
  11 {
  12 #ifdef _OPENMP
  13   if (omp_get_max_threads() > 4)
  14     omp_set_num_threads(4);
  15   if (omp_get_max_threads() < 2)
  16     omp_set_num_threads(2);
  17 #endif
  18
  19   int counter = 0;
  20 #ifdef _OPENMP
  21   omp_set_nested(1);
  22   omp_set_max_active_levels(omp_get_supported_active_levels());
  23 #endif
  24
  25   #pragma omp parallel shared(counter)
  26   {
  27     #pragma omp critical
  28     counter++;
  29     #pragma omp parallel
  30     {
  31       #pragma omp critical
  32       counter--;
  33     }
  34   }
  35   return (counter != 0);
  36 }
  37
  38 int main()
  39 {
  40   int i;
  41   int num_failed=0;
  42
  43   for(i = 0; i < REPETITIONS; i++) {
  44     if(!test_omp_nested()) {
  45       num_failed++;
  46     }
  47   }
  48   return num_failed;
  49 }