https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85512
--- Comment #2 from ktkachov at gcc dot gnu.org --- Indeed a SSHR by zero is not valid. One would hope that the optimisers would have eliminated the shift by zero by this point but the constraints on the *aarch64_ashr_sisd_or_int_si3 pattern need tightening
