libgomp/testsuite/libgomp.c/omp-loop01.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <omp.h>
   5
   6 #define MAX     1000
   7
   8 void main1()
   9 {
  10   int i, N1, N2, step;
  11   int a[MAX], b[MAX];
  12
  13   N1 = rand () % 13;
  14   N2 = rand () % (MAX - 51) + 50;
  15   step = rand () % 7 + 1;
  16
  17   printf ("N1 = %d\nN2 = %d\nstep = %d\n", N1, N2, step);
  18
  19   for (i = N1; i <= N2; i += step)
  20     a[i] = 42+ i;
  21
  22   /* COUNTING UP (<).  Fill in array 'b' in parallel.  */
  23   memset (b, 0, sizeof b);
  24 #pragma omp parallel shared(a,b,N1,N2,step) private(i)
  25   {
  26 #pragma omp for
  27     for (i = N1; i < N2; i += step)
  28       b[i] = a[i];
  29   }
  30
  31   /* COUNTING UP (<).  Check that all the cells were filled in properly.  */
  32   for (i = N1; i < N2; i += step)
  33     if (a[i] != b[i])
  34       abort ();
  35
  36   printf ("for (i = %d; i < %d; i += %d) [OK]\n", N1, N2, step);
  37
  38   /* COUNTING UP (<=).  Fill in array 'b' in parallel.  */
  39   memset (b, 0, sizeof b);
  40 #pragma omp parallel shared(a,b,N1,N2,step) private(i)
  41   {
  42 #pragma omp for
  43     for (i = N1; i <= N2; i += step)
  44       b[i] = a[i];
  45   }
  46
  47   /* COUNTING UP (<=).  Check that all the cells were filled in properly.  */
  48   for (i = N1; i <= N2; i += step)
  49     if (a[i] != b[i])
  50       abort ();
  51
  52   printf ("for (i = %d; i <= %d; i += %d) [OK]\n", N1, N2, step);
  53
  54   /* COUNTING DOWN (>).  Fill in array 'b' in parallel.  */
  55   memset (b, 0, sizeof b);
  56 #pragma omp parallel shared(a,b,N1,N2,step) private(i)
  57   {
  58 #pragma omp for
  59     for (i = N2; i > N1; i -= step)
  60       b[i] = a[i];
  61   }
  62
  63   /* COUNTING DOWN (>).  Check that all the cells were filled in properly.  */
  64   for (i = N2; i > N1; i -= step)
  65     if (a[i] != b[i])
  66       abort ();
  67
  68   printf ("for (i = %d; i > %d; i -= %d) [OK]\n", N2, N1, step);
  69
  70   /* COUNTING DOWN (>=).  Fill in array 'b' in parallel.  */
  71   memset (b, 0, sizeof b);
  72 #pragma omp parallel shared(a,b,N1,N2,step) private(i)
  73   {
  74 #pragma omp for
  75     for (i = N2; i >= N1; i -= step)
  76       b[i] = a[i];
  77   }
  78
  79   /* COUNTING DOWN (>=).  Check that all the cells were filled in properly.  */
  80   for (i = N2; i >= N1; i -= step)
  81     if (a[i] != b[i])
  82       abort ();
  83
  84   printf ("for (i = %d; i >= %d; i -= %d) [OK]\n", N2, N1, step);
  85 }
  86
  87 int
  88 main ()
  89 {
  90   int i;
  91
  92   srand (0);
  93   for (i = 0; i < 10; ++i)
  94     main1();
  95   return 0;
  96 }