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#include <stdio.h>
#include "opari_omp.h"
static void log(const char* msg, int val) {
printf("--- %3d: %s", omp_get_thread_num(), msg);
if ( val != -1 ) printf(" %d", val);
printf("\n");
fflush(stdout);
}
const int iterations = 4;
int main() {
int i, k = 0;
omp_lock_t lck;
#pragma omp inst init
log("sequential", 0);
/* ---- plain parallel region ---- */
#pragma omp parallel
{
log("parallel", 0);
}
log("sequential", 1);
/* ---- large parallel region ---- */
#pragma omp parallel
{
log("parallel", 1);
#pragma omp inst begin(worksharing)
/* ---- worksharing for loop without synchronisation ---- */
#pragma omp for nowait
for(i=0; i<iterations; ++i) {
log("for nowait iteration", i);
}
/* ---- user specified barrier ---- */
#pragma omp barrier
/* ---- worksharing for loop with implicit synchronisation ---- */
#pragma omp for
for(i=0; i<iterations; ++i)
log("for iteration", i);
/* ---- worksharing tasks without synchronisation ---- */
#pragma omp sections nowait
{
#pragma omp section
log("section nowait", 1);
#pragma omp section
{
log("section nowait", 2);
}
}
/* ---- worksharing tasks with implicit synchronisation ---- */
#pragma omp sections
{
#pragma omp section
{
log("section", 1);
}
#pragma omp section
log("section", 2);
}
#pragma omp inst end(worksharing)
#pragma omp inst begin(synchronisation)
/* ---- critical section ---- */
#pragma omp critical
{
log("critical\n", -1);
k += 1;
}
/* ---- named critical section ---- */
#pragma omp critical(kincr)
{
log("critical\n", -1);
k += 1;
}
/* ---- atomic expression ---- */
#pragma omp atomic
k += 1;
/* ---- update k just once without synchronisation ---- */
#pragma omp single nowait
{
log("single nowait\n", -1);
k += 1;
}
/* ---- update k just once with implicit synchronisation ---- */
#pragma omp single
{
log("single\n", -1);
k += 1;
}
#pragma omp master
{
log("master\n", -1);
printf("k = %d\n", k);
k = 0;
}
#pragma omp inst end(synchronisation)
} /* end parallel ---- */
log("sequential", 2);
#pragma omp inst begin(parallelworksharing)
/* ---- combined parallel worksharing for loop ---- */
#pragma omp parallel for \
reduction(+:k) \
private(i) \
schedule(dynamic)
for(i=0; i<iterations; ++i) {
log("pfor", i);
}
log("sequential", 3);
/* ---- combined parallel worksharing tasks ---- */
#pragma omp parallel sections
{
#pragma omp section
log("psection", 1);
#pragma omp section
log("psection", 2);
}
log("sequential", 4);
#pragma omp inst end(parallelworksharing)
/* ---- OpenMP locking API ---- */
#pragma omp inst begin(locking)
omp_init_lock(&lck);
#pragma omp parallel shared(lck)
{
omp_set_lock(&lck);
log("got lock", -1);
omp_unset_lock(&lck);
while (! omp_test_lock(&lck)) {
log("skipping", -1);
}
log("working", -1);
omp_unset_lock(&lck);
}
omp_destroy_lock(&lck);
#pragma omp flush(k)
#pragma omp inst end(locking)
}
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