(** *** Lemmas about invariants preserved by coresteps*)

(** [invariant] is preserved by a corestep *)
Lemma initial_core_invariant:
forall (tp : t)  (m : mem) (i : nat) n
(pf : containsThread tp i) c m1 m' vf arg
(Hinv: invariant tp)
(Hcompatible: mem_compatible tp m)
(Hrestrict_pmap: restrPermMap (DryHybridMachine.compat_th _ _ Hcompatible pf).1 = m1)
(Hcorestep: initial_core semSem n m1 c m' vf arg),
invariant (updThread pf (Krun c) (getCurPerm m', (getThreadR pf).2)).