gcc/testsuite/gcc.dg/vect/vect-alias-check.c

   1 /* { dg-do compile } */
   2 /* { dg-require-effective-target vect_int } */
   3 /* { dg-additional-options "--param=vect-max-version-for-alias-checks=2" } */
   4
   5 /* A test case showing four potential alias checks between a[i] and b[0], b[1],
   6    b[i+1] and b[i+2].  With alias check merging enabled, those four checks
   7    can be merged into two, and the loop will be vectorized with
   8    vect-max-version-for-alias-checks=2.  */
   9
  10 void foo (int *a, int *b)
  11 {
  12   int i;
  13   for (i = 0; i < 1000; ++i)
  14     a[i] = b[0] + b[1] + b[i+1] + b[i+2];
  15 }
  16
  17 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" } } */