libgomp/testsuite/libgomp.c/omp_workshare4.c

   1 /******************************************************************************
   2 * OpenMP Example - Combined Parallel Loop Work-sharing - C/C++ Version
   3 * FILE: omp_workshare4.c
   4 * DESCRIPTION:
   5 *   This is a corrected version of the omp_workshare3.c example. Corrections
   6 *   include removing all statements between the parallel for construct and
   7 *   the actual for loop, and introducing logic to preserve the ability to
   8 *   query a thread's id and print it from inside the for loop.
   9 * SOURCE: Blaise Barney  5/99
  10 * LAST REVISED: 03/03/2002
  11 ******************************************************************************/
  12
  13 #include <omp.h>
  14 #include <stdio.h>
  15 #define N       50
  16 #define CHUNKSIZE   5
  17
  18 int
  19 main ()  {
  20
  21 int i, chunk, tid;
  22 float a[N], b[N], c[N];
  23 char first_time;
  24
  25 /* Some initializations */
  26 for (i=0; i < N; i++)
  27   a[i] = b[i] = i * 1.0;
  28 chunk = CHUNKSIZE;
  29 first_time = 'y';
  30
  31 #pragma omp parallel for     \
  32   shared(a,b,c,chunk)            \
  33   private(i,tid)             \
  34   schedule(static,chunk)     \
  35   firstprivate(first_time)
  36
  37   for (i=0; i < N; i++)
  38     {
  39     if (first_time == 'y')
  40       {
  41       tid = omp_get_thread_num();
  42       first_time = 'n';
  43       }
  44     c[i] = a[i] + b[i];
  45     printf("tid= %d i= %d c[i]= %f\n", tid, i, c[i]);
  46     }
  47
  48   return 0;
  49 }