Definition orimm_redundant (x: nval) (n: int) :=
  match x with
  | Nothing => true
  | I m => Int.eq_dec (Int.and m n) Int.zero
  | _ => false
  end.

Lemma orimm_redundant_sound: forall v w x n, orimm_redundant x n = true -> vagree v w (orimm x n) -> vagree (Val.or v (Vint n)) w x.