gcc/testsuite/gcc.dg/tree-ssa/reassoc-1.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-optimized" } */
   3
   4 int a, b, c, d;
   5 extern int printf (const char *, ...);
   6 int main(void)
   7 {
   8   int e;
   9   int f;
  10   /* We should be able to transform these into the same expression, and only have two additions.  */
  11   e = a + b;
  12   e = e + c;
  13   f = c + a;
  14   f = f + b;
  15   printf ("%d %d\n", e, f);
  16 }
  17
  18 /* We cannot reassociate these expressions because of undefined signed
  19    integer overflow.  Instead the value-numberer has to be extended
  20    to canonicalize these expressions.  */
  21
  22 /* { dg-final { scan-tree-dump-times "b.._. \\\+ a.._." 1 "optimized" { xfail *-*-* } } } */
  23 /* { dg-final { scan-tree-dump-times " \\\+ " 2 "optimized" { xfail *-*-* } } } */