Definition classify_add' ty1 ty2 :=
 match stupid_typeconv ty1 with
 | Tint _ si _ =>
    match stupid_typeconv ty2 with
    | Tpointer ty a => add_case_ip si ty
    |  _ => add_default
    end
| Tlong _ _ =>
    match stupid_typeconv ty2 with
    | Tpointer ty a => add_case_lp ty
    | _ => add_default
    end
| Tpointer ty a =>
    match stupid_typeconv ty2 with
    | Tint _ si _ => add_case_pi ty si
    | Tlong _ _ => add_case_pl ty
    | _ => add_default
    end
 | _ => add_default
end.

Lemma classify_add_eq: classify_add = classify_add'.