(** * Compatibility with memory injections *)

(** Relating two memory values according to a memory injection. *)

Inductive memval_inject (f: meminj): memval -> memval -> Prop :=
  | memval_inject_byte:
      forall n, memval_inject f (Byte n) (Byte n)
  | memval_inject_frag:
      forall v1 v2 q n,
      Val.inject f v1 v2 ->
      memval_inject f (Fragment v1 q n) (Fragment v2 q n)
  | memval_inject_undef:
      forall mv, memval_inject f Undef mv.(** * Compatibility with memory injections *)

(** Relating two memory values according to a memory injection. *)

Inductive memval_inject (f: meminj): memval -> memval -> Prop :=
  | memval_inject_byte:
      forall n, memval_inject f (Byte n) (Byte n)
  | memval_inject_frag:
      forall v1 v2 q n,
      Val.inject f v1 v2 ->
      memval_inject f (Fragment v1 q n) (Fragment v2 q n)
  | memval_inject_undef:
      forall mv, memval_inject f Undef mv.(** * Compatibility with memory injections *)

(** Relating two memory values according to a memory injection. *)

Inductive memval_inject (f: meminj): memval -> memval -> Prop :=
  | memval_inject_byte:
      forall n, memval_inject f (Byte n) (Byte n)
  | memval_inject_frag:
      forall v1 v2 q n,
      Val.inject f v1 v2 ->
      memval_inject f (Fragment v1 q n) (Fragment v2 q n)
  | memval_inject_undef:
      forall mv, memval_inject f Undef mv.(** * Compatibility with memory injections *)

(** Relating two memory values according to a memory injection. *)

Inductive memval_inject (f: meminj): memval -> memval -> Prop :=
  | memval_inject_byte:
      forall n, memval_inject f (Byte n) (Byte n)
  | memval_inject_frag:
      forall v1 v2 q n,
      Val.inject f v1 v2 ->
      memval_inject f (Fragment v1 q n) (Fragment v2 q n)
  | memval_inject_undef:
      forall mv, memval_inject f Undef mv.

Lemma proj_bytes_not_inject: forall f vl vl', list_forall2 (memval_inject f) vl vl' -> proj_bytes vl = None -> proj_bytes vl' <> None -> In Undef vl.