Definition ror (x y: aval) :=
  match y, x with
  | I j, I i => I(Int.ror i j)
  | _, _ => ntop1 x
  end.

(* Specifications: *)
Lemma ror_sound: forall v w x y, vmatch v x -> vmatch w y -> vmatch (Val.ror v w) (ror x y).