[Bug tree-optimization/109689] [14 Regression] ICE at -O1 with "-ftree-vectorize": in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109689

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
LC SSA is broken by unloop_loops ().  That introduces BB 19 which is

<bb 19> [count: 0]:
f.8_13 = (unsigned char) f_19;
_14 = f.8_13 + 1;
f_38 = (char) _14;
_16 = a_lsm.17_51 + 1;
__builtin_unreachable ();

but that's an exit from the loop and is missing LC PHI nodes for all of the
SSA names used.