Function antic::n_powmod_ui_preinv

pub unsafe extern "C" fn n_powmod_ui_preinv(
    a: mp_limb_t, 
    exp: mp_limb_t, 
    n: mp_limb_t, 
    ninv: mp_limb_t, 
    norm: mp_limb_t
) -> mp_limb_t