[Bug tree-optimization/103647] constant array comparison not always folded

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103647

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2021-12-10
           Severity|normal                      |enhancement
     Ever confirmed|0                           |1

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So in fab GCC creates:
  a = "ac";
  b = "ab";
  _8 = MEM <unsigned short> [(char * {ref-all})&a];
  _9 = MEM <unsigned short> [(char * {ref-all})&b];
  _10 = _8 != _9;

And:
  a = "ab";
  b = "abc";
  _8 = MEM <unsigned short> [(char * {ref-all})&a];
  _9 = MEM <unsigned short> [(char * {ref-all})&b];
  _10 = _8 != _9;

But we don't have a FRE/DOM to optimize those MEM_REFs.

Confirmed.