gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-1.c

   1 /* { dg-require-effective-target vect_int } */
   2
   3 #include <stdarg.h>
   4 #include "tree-vect.h"
   5
   6 #define N 17
   7
   8 __attribute__ ((noinline))
   9 int main1 ()
  10 {
  11   int i;
  12   int ia[N] = {0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48};
  13   int ib[N] = {0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48};
  14   int res[N] = {12,24,36,48,60,72,84,96,108,120,132,144,156,168,180,192,48};
  15
  16   /* Not vectorizable due to data dependence: dependence distance 1.  */
  17   for (i = 0; i < N - 1; i++)
  18     {
  19       ia[i+1] = ia[i] * 4;
  20     }
  21
  22   /* check results:  */
  23   for (i = 0; i < N - 1; i++)
  24     {
  25       if (ia[i] != 0)
  26         abort ();
  27     }
  28
  29   /* Vectorizable. Dependence distance -1.  */
  30   for (i = 0; i < N - 1; i++)
  31     {
  32       ib[i] = ib[i+1] * 4;
  33     }
  34
  35   /* check results:  */
  36   for (i = 0; i < N - 1; i++)
  37     {
  38       if (ib[i] != res[i])
  39         abort ();
  40     }
  41
  42   return 0;
  43 }
  44
  45 int main (void)
  46 {
  47   check_vect();
  48
  49   return main1 ();
  50 }
  51
  52 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect"  } } */
  53 /* { dg-final { scan-tree-dump-times "dependence distance >= VF or negative" 1 "vect"  } } */
  54 /* { dg-final { cleanup-tree-dump "vect" } } */
  55