(* Build an [rmap] that's identical to [phi] except where [m] has stored. *)
Definition inflate_store: rmap.

Lemma adr_inv: forall (b b': block) (ofs ofs': Z) ch, ~ adr_range (b, ofs) (size_chunk ch) (b', ofs') -> b <> b' \/ ~ ofs <= ofs' < ofs + size_chunk ch.