(** ** Semantics of volatile stores *)

Inductive volatile_store_sem (chunk: memory_chunk) (ge: Senv.t):
              list val -> mem -> trace -> val -> mem -> Prop :=
  | volatile_store_sem_intro: forall b ofs m1 v t m2,
      volatile_store ge chunk m1 b ofs v t m2 ->
      volatile_store_sem chunk ge (Vptr b ofs :: v :: nil) m1 t Vundef m2.(** ** Semantics of volatile stores *)

Inductive volatile_store_sem (chunk: memory_chunk) (ge: Senv.t):
              list val -> mem -> trace -> val -> mem -> Prop :=
  | volatile_store_sem_intro: forall b ofs m1 v t m2,
      volatile_store ge chunk m1 b ofs v t m2 ->
      volatile_store_sem chunk ge (Vptr b ofs :: v :: nil) m1 t Vundef m2.

(* Specifications: *)
Lemma volatile_store_preserved: forall ge1 ge2 chunk m1 b ofs v t m2, Senv.equiv ge1 ge2 -> volatile_store ge1 chunk m1 b ofs v t m2 -> volatile_store ge2 chunk m1 b ofs v t m2.
Lemma volatile_store_readonly: forall ge chunk1 m1 b1 ofs1 v t m2, volatile_store ge chunk1 m1 b1 ofs1 v t m2 -> Mem.unchanged_on (loc_not_writable m1) m1 m2.
Lemma volatile_store_extends: forall ge chunk m1 b ofs v t m2 m1' v', volatile_store ge chunk m1 b ofs v t m2 -> Mem.extends m1 m1' -> Val.lessdef v v' -> exists m2', volatile_store ge chunk m1' b ofs v' t m2' /\ Mem.extends m2 m2' /\ Mem.unchanged_on (loc_out_of_bounds m1) m1' m2'.
Lemma volatile_store_inject: forall ge1 ge2 f chunk m1 b ofs v t m2 m1' b' ofs' v', symbols_inject f ge1 ge2 -> volatile_store ge1 chunk m1 b ofs v t m2 -> Val.inject f (Vptr b ofs) (Vptr b' ofs') -> Val.inject f v v' -> Mem.inject f m1 m1' -> exists m2', volatile_store ge2 chunk m1' b' ofs' v' t m2' /\ Mem.inject f m2 m2' /\ Mem.unchanged_on (loc_unmapped f) m1 m2 /\ Mem.unchanged_on (loc_out_of_reach f m1) m1' m2'.
Lemma volatile_store_receptive: forall ge chunk m b ofs v t1 m1 t2, volatile_store ge chunk m b ofs v t1 m1 -> match_traces ge t1 t2 -> t1 = t2.
Lemma volatile_store_ok: forall chunk, extcall_properties (volatile_store_sem chunk) (mksignature (Tptr :: type_of_chunk chunk :: nil) None cc_default).