[Bug target/123447] [15/16 Regression] ICE: in simplify_gen_subreg_concatn, at lower-subreg.cc:744 with -O2 -mstrict-align and large vectors

[pfustc at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123447

--- Comment #5 from Pengfei Li <pfustc at gcc dot gnu.org> ---
started with
https://gcc.gnu.org/cgit/gcc/commit/?id=54bdeca3c6214485d15454df30183a56ad3e473b