Definition bmatch (m: mem) (b: block) (ab: ablock) : Prop :=
  smatch m b ab.(ab_summary) /\
  forall chunk ofs v, Mem.load chunk m b ofs = Some v -> vmatch v (ablock_load chunk ab ofs).

Lemma ablock_storebytes_sound: forall m b ofs bytes m' p ab sz, Mem.storebytes m b ofs bytes = Some m' -> length bytes = nat_of_Z sz -> (forall b' ofs' q i, In (Fragment (Vptr b' ofs') q i) bytes -> pmatch b' ofs' p) -> bmatch m b ab -> bmatch m' b (ablock_storebytes ab p ofs sz).