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

   1 /* { dg-require-effective-target vect_int } */
   2 /* { dg-additional-options "--param vect-max-version-for-alias-checks=0" } */
   3
   4 #include <stdarg.h>
   5 #include "tree-vect.h"
   6
   7 #define N 17
   8
   9 int ia[N] = {0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48};
  10 int ib[N] = {0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48};
  11 int res[N] = {12,24,36,48,60,72,84,96,108,120,132,144,156,168,180,192,48};
  12
  13 __attribute__ ((noinline))
  14 int main1 ()
  15 {
  16   int i;
  17
  18   /* Not vectorizable due to data dependence: dependence distance 1.  */
  19   for (i = 0; i < N - 1; i++)
  20     {
  21       ia[i+1] = ia[i] * 4;
  22     }
  23
  24   /* check results:  */
  25 #pragma GCC novector
  26   for (i = 0; i < N - 1; i++)
  27     {
  28       if (ia[i] != 0)
  29         abort ();
  30     }
  31
  32   /* Vectorizable. Dependence distance -1.  */
  33   for (i = 0; i < N - 1; i++)
  34     {
  35       ib[i] = ib[i+1] * 4;
  36     }
  37
  38   /* check results:  */
  39 #pragma GCC novector
  40   for (i = 0; i < N - 1; i++)
  41     {
  42       if (ib[i] != res[i])
  43         abort ();
  44     }
  45
  46   return 0;
  47 }
  48
  49 int main (void)
  50 {
  51   check_vect();
  52
  53   return main1 ();
  54 }
  55
  56 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" {xfail { vect_no_align && { ! vect_hw_misalign } } } } } */
  57 /* { dg-final { scan-tree-dump-times "dependence distance negative" 1 "vect"  } } */
  58