Set Bullet Behavior "Strict Subproofs".
(* standard VST prelude *)
Instance CompSpecs : compspecs. make_compspecs prog. Defined.
Definition Vprog : varspecs. mk_varspecs prog. Defined.
(* import funspecs from concurrency library *)
Definition acquire_spec := DECLARE _acquire acquire_spec.
Definition release_spec := DECLARE _release release_spec.
Section AEHist.
(* These histories should be usable for any atomically accessed location. *)
Inductive AE_hist_el := AE (r : val) (w : val).
Fixpoint apply_hist a h :=
match h with
| [] => Some a
| AE r w :: h' => if eq_dec r a then apply_hist w h' else None
end.
Arguments eq_dec _ _ _ _ : simpl never.

Lemma apply_hist_app : forall h1 i h2, apply_hist i (h1 ++ h2) =
match apply_hist i h1 with Some v => apply_hist v h2 | None => None end.