[Bug tree-optimization/95409] Failure to xor register before usage of 8-bit part in some bitshifting situations

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95409

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-04-21
             Status|UNCONFIRMED                 |NEW
           Severity|normal                      |enhancement
          Component|target                      |tree-optimization
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.

They produce at the tree level:
  _1 = ~x_7(D);
  _4 = x.2_2 < y.3_3;
  _5 = (int) _4;
  _6 = _1 & _5;
  _9 = (bool) _6;
------------------------
  _3 = x.4_1 < y.5_2;
  _11 = ~x_7(D);
  _5 = (bool) _11;
  _6 = _3 & _5;
-------------------------------
That is it does not convert:
  _5 = (int) _4;
  _6 = _1 & _5;
  _9 = (bool) _6;

Into:
  _t = (bool) _1;
  _6 = _t & _4;