lcb: Aarch64 cannot differentiate between 32 and 64 bit

[kper]

The compiler generator generates the following patterns but cannot distinguish them:

def : Pat<(udiv S:$rn, S:$rm),
        (UDIVW S:$rm, S:$rn)>;


def : Pat<(udiv S:$rn, S:$rm),
        (UDIVX S:$rm, S:$rn)>;