[Bug tree-optimization/125793] phi_opt should factor out calls

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125793

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I'll mention tail merging here (which can only merge full equal blocks, not
tails of blocks).