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| // RUN: %libomp-compile-and-run
#include <stdio.h>
#include "omp_testsuite.h"
/*
* This test will hang if the nowait is not working properly.
*
* It relies on a thread skipping to the second for construct to
* release the threads in the first for construct.
*
* Also, we use static scheduling to guarantee that one
* thread will make it to the second for construct.
*/
volatile int release;
volatile int count;
void wait_for_release_then_increment(int rank)
{
fprintf(stderr, "Thread nr %d enters first for construct"
" and waits.\n", rank);
while (release == 0);
#pragma omp atomic
count++;
}
void release_and_increment(int rank)
{
fprintf(stderr, "Thread nr %d sets release to 1\n", rank);
release = 1;
#pragma omp atomic
count++;
}
int test_omp_for_nowait()
{
release = 0;
count = 0;
#pragma omp parallel num_threads(4)
{
int rank;
int i;
rank = omp_get_thread_num();
#pragma omp for schedule(static) nowait
for (i = 0; i < 4; i++) {
if (i < 3)
wait_for_release_then_increment(rank);
else {
fprintf(stderr, "Thread nr %d enters first for and goes "
"immediately to the next for construct to release.\n", rank);
#pragma omp atomic
count++;
}
}
#pragma omp for schedule(static)
for (i = 0; i < 4; i++) {
release_and_increment(rank);
}
}
return (count==8);
}
int main()
{
int i;
int num_failed=0;
for(i = 0; i < REPETITIONS; i++) {
if(!test_omp_for_nowait()) {
num_failed++;
}
}
return num_failed;
}
|