gcc/testsuite/gcc.dg/vect/vect-35.c

   1 /* { dg-require-effective-target vect_int } */
   2
   3 #include <stdarg.h>
   4 #include "tree-vect.h"
   5
   6 #define N 16
   7
   8 __attribute__ ((noinline))
   9 int main1 ()
  10 {
  11   union {
  12     unsigned char a[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  13     unsigned char b[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  14   } s;
  15   int i;
  16
  17   /* Initialization.  */
  18   for (i = 0; i < N; i++)
  19     {
  20       s.b[i] = i;
  21     }
  22
  23   /* Dependence analysis fails cause s.a and s.b may overlap.
  24      Try to use runtime aliasing test with versioning, and
  25      later versioning/vectorization are skipped because the
  26      overlap is proven at compilation time.  */
  27   for (i = 0; i < N; i++)
  28     {
  29       s.a[i] = s.b[i] + 1;
  30     }
  31
  32   /* check results:  */
  33   for (i = 0; i < N; i++)
  34     {
  35       if (s.a[i] != i + 1)
  36         abort ();
  37     }
  38
  39   return 0;
  40 }
  41
  42 int main (void)
  43 {
  44   check_vect ();
  45
  46   return main1 ();
  47 }
  48
  49
  50 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect"  { xfail { ia64-*-* sparc*-*-* } } } } */
  51 /* { dg-final { scan-tree-dump "can't determine dependence between" "vect" } } */