[Bug tree-optimization/103079] [12 Regression] wrong code at -Os and -O2 on x86_64-linux-gnu (the generated code hangs) since r12-4871-g502ffb1f389011b2

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103079

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The problem is latent though. The issue is reassociatation introduces an
unconditional use of an uninitilized vairable:
Before
  if (b.1_3 != 0)
    goto <bb 4>; [34.00%]
  else
    goto <bb 3>; [66.00%]

  <bb 3> [local count: 116348739]:
  if (_5(D) != 0)
    goto <bb 4>; [50.00%]
  else
    goto <bb 8>; [50.00%]
After:
  _6 = _5(D) | b.1_3;
  _7 = _6 != 0;
  if (_7 != 0)
    goto <bb 3>; [34.00%]
  else
    goto <bb 7>; [66.00%]