gcc/testsuite/gcc.dg/pr44838.c

   1 /* PR rtl-optimization/44838 */
   2 /* { dg-do run } */
   3 /* { dg-options "-O2 -funroll-loops" } */
   4
   5 extern void abort ();
   6
   7 void
   8 foo (int *a, int n)
   9 {
  10   int *lasta = a + n;
  11   for (; a != lasta; a++)
  12     {
  13       *a *= 2;
  14       a[1] = a[-1] + a[-2];
  15     }
  16 }
  17
  18 int a[16];
  19 int ref[16] = { 0, 1, 4, 2, 10, 12, 24, 44,
  20                 72, 136, 232, 416, 736, 1296, 2304, 2032 };
  21
  22 int
  23 main ()
  24 {
  25   int i;
  26   for (i = 0; i < 16; i++)
  27     a[i] = i;
  28   foo (a + 2, 16 - 3);
  29   for (i = 0; i < 16; i++)
  30     if (ref[i] != a[i])
  31       abort ();
  32   return 0;
  33 }