[Bug tree-optimization/122493] is_eye in leela is not split because of empty basic block (merge_phi should be part of cfgcleanup instead of its own pass)

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122493

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
IIRC PHI merging sometimes splits edges, creating forwarders - I'm not sure we
want to preserve that in CFG cleanup.