Definition notint (v: aval) :=
match v with
| I i => I (Int.not i)
| Uns p n => sgn p (n + 1)
| Sgn p n => Sgn p n
| _ => ntop1 v
end.

Lemma notint_sound:
forall v x, vmatch v x -> vmatch (Val.notint v) (notint x).