[Bug tree-optimization/114099] [14 regression] ICE in find_uses_to_rename_use when building darktable-4.6.1

[tnfchris at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114099

--- Comment #8 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
Created attachment 57537
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57537&action=edit
uses.patch

new code seems sensitive to visitation order as get_virtual_phi returns NULL
for blocks which don't define or use a virtual PHI.

testing patch.