gcc/testsuite/gcc.dg/tree-ssa/predcom-5.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -funroll-loops --param max-unroll-times=8 -fpredictive-commoning -fdump-tree-pcom-details" } */
   3
   4 /* Test for predictive commoning of expressions, with reassociation.  */
   5
   6 void abort (void);
   7
   8 unsigned a[1000], b[1000], c[1000], d[1000];
   9
  10 int main(void)
  11 {
  12   unsigned i;
  13
  14   for (i = 0; i < 1000; i++)
  15     a[i] = b[i] = d[i] = i;
  16
  17   for (i = 1; i < 998; i++)
  18     c[i] = d[i + 1] * a[i + 2] * b[i + 1] - b[i - 1] * a[i] * d[i - 1];
  19
  20   for (i = 1; i < 998; i++)
  21     if (c[i] != (i+1)*(i+2)*(i+1) - (i - 1) * i * (i - 1))
  22       abort ();
  23
  24   return 0;
  25 }
  26
  27 /* { dg-final { scan-tree-dump-times "Combination" 2 "pcom"} } */
  28 /* { dg-final { scan-tree-dump-times "Unrolling 3 times." 1 "pcom"} } */