Ltac InvEval :=
  match goal with
  | [ H: None = Some _ |- _ ] => discriminate
  | [ H: Some _ = Some _ |- _ ] => inv H; InvEval
  | [ H: match ?x with Some _ => _ | None => _ end = Some _ |- _ ] => destruct x eqn:?; InvEval
  | [ H: match ?x with true => _ | false => _ end = Some _ |- _ ] => destruct x eqn:?; InvEval
  | _ => idtac
  end.

(* Specifications: *)
Lemma make_cast_correct: forall e le m a b v ty1 ty2 v', make_cast ty1 ty2 a = OK b -> eval_expr ge e le m a v -> sem_cast v ty1 ty2 m = Some v' -> eval_expr ge e le m b v'.
Lemma make_boolean_correct: forall e le m a v ty b, eval_expr ge e le m a v -> bool_val v ty m = Some b -> exists vb, eval_expr ge e le m (make_boolean a ty) vb /\ Val.bool_of_val vb b.
Lemma make_neg_correct: forall a tya c va v e le m, sem_neg va tya = Some v -> make_neg a tya = OK c -> eval_expr ge e le m a va -> eval_expr ge e le m c v.
Lemma make_absfloat_correct: forall a tya c va v e le m, sem_absfloat va tya = Some v -> make_absfloat a tya = OK c -> eval_expr ge e le m a va -> eval_expr ge e le m c v.
Lemma make_notbool_correct: forall a tya c va v e le m, sem_notbool va tya m = Some v -> make_notbool a tya = OK c -> eval_expr ge e le m a va -> eval_expr ge e le m c v.
Lemma make_notint_correct: forall a tya c va v e le m, sem_notint va tya = Some v -> make_notint a tya = OK c -> eval_expr ge e le m a va -> eval_expr ge e le m c v.