gcc/testsuite/gcc.dg/tree-ssa/reassoc-2.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-optimized" } */
   3
   4 int f (int a0,int a1,int a2,int a3,int a4)
   5 {
   6 int b0, b1, b2, b3, b4,e;
   7   /* this can be optimized to four additions... */
   8   b4 = a4 + a3 + a2 + a1 + a0;
   9   b3 = a3 + a2 + a1 + a0;
  10   b2 = a2 + a1 + a0;
  11   b1 = a1 + a0;
  12   /* This is actually 0 */
  13   e = b4 - b3 + b2 - b1 - a4 - a2;
  14   return e;
  15 }
  16
  17 /* We can't reassociate the expressions due to undefined signed overflow.  */
  18
  19 /* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
  20 /* { dg-final { cleanup-tree-dump "optimized" } } */