https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121358
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- So I think the problem is force_subreg expected simplify_gen_subreg would simplify the subreg of the const_vector into a const_int but in this case we don't as we don't have a way to simplify const_vectors with const_poly_int.
