[Bug tree-optimization/121753] [16 Regression] Recent vectorizer changes causes ICE in vect_build_slp_tree_2

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121753

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
So this is another pattern case breaking reductions, we turn c * 4 into

  patt_22 = c.0_1 + c.0_1;
  patt_7 = patt_22 + patt_22;

which we cannot handle as reduction.