mirror of git://gcc.gnu.org/git/gcc.git
48 lines
1004 B
C
48 lines
1004 B
C
/******************************************************************************
|
|
* FILE: omp_orphan.c
|
|
* DESCRIPTION:
|
|
* OpenMP Example - Parallel region with an orphaned directive - C/C++ Version
|
|
* This example demonstrates a dot product being performed by an orphaned
|
|
* loop reduction construct. Scoping of the reduction variable is critical.
|
|
* AUTHOR: Blaise Barney 5/99
|
|
* LAST REVISED: 04/06/05
|
|
******************************************************************************/
|
|
#include <omp.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#define VECLEN 100
|
|
|
|
float a[VECLEN], b[VECLEN], sum;
|
|
|
|
float dotprod ()
|
|
{
|
|
int i,tid;
|
|
|
|
tid = omp_get_thread_num();
|
|
#pragma omp for reduction(+:sum)
|
|
for (i=0; i < VECLEN; i++)
|
|
{
|
|
sum = sum + (a[i]*b[i]);
|
|
printf(" tid= %d i=%d\n",tid,i);
|
|
}
|
|
|
|
return(sum);
|
|
}
|
|
|
|
|
|
int main (int argc, char *argv[])
|
|
{
|
|
int i;
|
|
|
|
for (i=0; i < VECLEN; i++)
|
|
a[i] = b[i] = 1.0 * i;
|
|
sum = 0.0;
|
|
|
|
#pragma omp parallel
|
|
sum = dotprod();
|
|
|
|
printf("Sum = %f\n",sum);
|
|
|
|
return 0;
|
|
}
|