82 lines
1.8 KiB
C
82 lines
1.8 KiB
C
/******************************************************************************
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* FILE: omp_bug3.c
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* DESCRIPTION:
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* Run time error
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******************************************************************************/
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#include <omp.h>
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#include <stdio.h>
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#include <stdlib.h>
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#define N 50
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int main(int argc, char *argv[]) {
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int i, nthreads, tid, section;
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float a[N], b[N], c[N];
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void print_results(float array[N], int tid, int section);
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/* Some initializations */
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for (i = 0; i < N; i++)
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a[i] = b[i] = i * 1.0;
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#pragma omp parallel private(c, i, tid, section)
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{
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tid = omp_get_thread_num();
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if (tid == 0) {
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nthreads = omp_get_num_threads();
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printf("Number of threads = %d\n", nthreads);
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}
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/*** Use barriers for clean output ***/
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#pragma omp barrier
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printf("Thread %d starting...\n", tid);
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#pragma omp barrier
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#pragma omp sections nowait
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{
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#pragma omp section
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{
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section = 1;
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for (i = 0; i < N; i++)
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c[i] = a[i] * b[i];
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print_results(c, tid, section);
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}
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#pragma omp section
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{
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section = 2;
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for (i = 0; i < N; i++)
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c[i] = a[i] + b[i];
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print_results(c, tid, section);
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}
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} /* end of sections */
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/*** Use barrier for clean output ***/
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#pragma omp barrier
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printf("Thread %d exiting...\n", tid);
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} /* end of parallel section */
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}
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void print_results(float array[N], int tid, int section) {
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int i, j;
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j = 1;
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/*** use critical for clean output ***/
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#pragma omp critical
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{
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printf("\nThread %d did section %d. The results are:\n", tid, section);
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for (i = 0; i < N; i++) {
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printf("%e ", array[i]);
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j++;
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if (j == 6) {
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printf("\n");
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j = 1;
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}
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}
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printf("\n");
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} /*** end of critical ***/
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#pragma omp barrier
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printf("Thread %d done and synchronized.\n", tid);
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}
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