Ltac UseGetSound :=
match goal with
| [ H: get _ = Some _ |- _ ] =>
let x := fresh "EQ" in (generalize (get_op_sound _ _ _ H); intros x; simpl in x; FuncInv)
end.

Theorem combine_cond_sound:
forall cond args cond' args',
combine_cond get cond args = Some(cond', args') ->
eval_condition cond' (map valu args') m = eval_condition cond (map valu args) m.