[Bug tree-optimization/125557] Missed if-conversion of load addresses

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125557

--- Comment #6 from Drea Pinski <pinskia at gcc dot gnu.org> ---
Note the final ifcvt part needs to have a decent cost model; right now your
patches don't have one and it is not obvious if it is always better especially
on targets which don't have a cmov (or cmov like instruction; e.g riscv's
czero.nez/czero.eqz). We need much more time on figuring that part out. Either
we should improve ifcvt or have something in the last phiopt. Having it as part
of sink breaks what sink is doing.