mirror of git://gcc.gnu.org/git/gcc.git
48 lines
1.2 KiB
C
48 lines
1.2 KiB
C
/******************************************************************************
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* FILE: omp_workshare1.c
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* DESCRIPTION:
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* OpenMP Example - Loop Work-sharing - C/C++ Version
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* In this example, the iterations of a loop are scheduled dynamically
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* across the team of threads. A thread will perform CHUNK iterations
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* at a time before being scheduled for the next CHUNK of work.
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* AUTHOR: Blaise Barney 5/99
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* LAST REVISED: 04/06/05
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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 CHUNKSIZE 10
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#define N 100
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int main (int argc, char *argv[]) {
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int nthreads, tid, i, chunk;
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float a[N], b[N], c[N];
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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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chunk = CHUNKSIZE;
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#pragma omp parallel shared(a,b,c,nthreads,chunk) private(i,tid)
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{
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tid = omp_get_thread_num();
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if (tid == 0)
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{
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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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printf("Thread %d starting...\n",tid);
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#pragma omp for schedule(dynamic,chunk)
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for (i=0; i<N; i++)
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{
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c[i] = a[i] + b[i];
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printf("Thread %d: c[%d]= %f\n",tid,i,c[i]);
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}
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} /* end of parallel section */
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return 0;
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}
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