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 main ()  {
  19
  20 int i, chunk, tid;
  21 float a[N], b[N], c[N];
  22 char first_time;
  23
  24 /* Some initializations */
  25 for (i=0; i < N; i++)
  26   a[i] = b[i] = i * 1.0;
  27 chunk = CHUNKSIZE;
  28 first_time = 'y';
  29
  30 #pragma omp parallel for     \
  31   shared(a,b,c,chunk)            \
  32   private(i,tid)             \
  33   schedule(static,chunk)     \
  34   firstprivate(first_time)
  35
  36   for (i=0; i < N; i++)
  37     {
  38     if (first_time == 'y')
  39       {
  40       tid = omp_get_thread_num();
  41       first_time = 'n';
  42       }
  43     c[i] = a[i] + b[i];
  44     printf("tid= %d i= %d c[i]= %f\n", tid, i, c[i]);
  45     }
  46
  47   return 0;
  48 }