(*Require Import VST.concurrency.cl_step_lemmas.*)
Set Bullet Behavior "Strict Subproofs".
(** Lemmas common to both parts of the progress/preservation simulation results *)
Definition pures_same phi1 phi2 := forall loc k pp, phi1 @ loc = PURE k pp <-> phi2 @ loc = PURE k pp.

Lemma pures_same_sym phi1 phi2 : pures_same phi1 phi2 -> pures_same phi2 phi1.