gcc/testsuite/gcc.dg/tree-ssa/reassoc-21.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-optimized" } */
   3
   4 unsigned int f (unsigned int a0, unsigned int a1, unsigned int a2,
   5                 unsigned int a3, unsigned int a4)
   6 {
   7   unsigned int b0, b1, b2, b3, b4, e;
   8   /* this can be optimized to four additions... */
   9   b4 = a4 + a3 + a2 + a1 + a0;
  10   b3 = a3 + a2 + a1 + a0;
  11   b2 = a2 + a1 + a0;
  12   b1 = a1 + a0;
  13   /* This is actually 0 */
  14   e = b4 - b3 + b2 - b1 - a4 - a2;
  15   return e;
  16 }
  17
  18 /* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
  19 /* { dg-final { cleanup-tree-dump "optimized" } } */