gcc/testsuite/gcc.dg/pr69195.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O3 -fno-dce -fno-forward-propagate" } */
   3
   4 void __attribute__ ((noinline, noclone))
   5 foo (int *a, int n)
   6 {
   7   int *lasta = a + n;
   8   for (; a != lasta; a++)
   9     {
  10       *a *= 2;
  11       a[1] = a[-1] + a[-2];
  12     }
  13 }
  14
  15 int
  16 main ()
  17 {
  18   int a[16] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
  19   int r[16] = { 1, 2, 6, 6, 16, 24, 44, 80,
  20                 136, 248, 432, 768, 1360, 2400, 4256, 3760 };
  21   unsigned i;
  22   foo (&a[2], 13);
  23   for (i = 0; i < 8; ++i)
  24     if (a[i] != r[i])
  25       __builtin_abort ();
  26   return 0;
  27 }