[Bug tree-optimization/126043] early phiopt should allow CMP, (cast)CMP, -(cast)CMP

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126043

--- Comment #1 from Drea Pinski <pinskia at gcc dot gnu.org> ---
Note the sequence might have more than one comparison due to the way match
works.