[Bug tree-optimization/122845] `a ^ CST ^ CST` is sometimes not folded at the gimple level (casts)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122845

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Created attachment 63315
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63315&action=edit
Patch in testing

This also resolves PR 122843.