(** Abstracting memory blocks *)

Inductive acontent : Type :=
 | ACval (chunk: memory_chunk) (av: aval).(** Abstracting memory blocks *)

Inductive acontent : Type :=
 | ACval (chunk: memory_chunk) (av: aval).Definition eq_acontent : forall (c1 c2: acontent), {c1=c2} + {c1<>c2}.Record ablock : Type := ABlock {
  ab_contents: ZTree.t acontent;
  ab_summary: aptr
}.Record ablock : Type := ABlock {
  ab_contents: ZTree.t acontent;
  ab_summary: aptr
}.Record ablock : Type := ABlock {
  ab_contents: ZTree.t acontent;
  ab_summary: aptr
}.Record ablock : Type := ABlock {
  ab_contents: ZTree.t acontent;
  ab_summary: aptr
}.Local Notation "a ## b" := (ZTree.get b a) (at level 1).Definition ablock_init (p: aptr) : ablock :=
  {| ab_contents := ZTree.empty _; ab_summary := p |}.Definition chunk_compat (chunk chunk': memory_chunk) : bool :=
  match chunk, chunk' with
  | (Mint8signed | Mint8unsigned), (Mint8signed | Mint8unsigned) => true
  | (Mint16signed | Mint16unsigned), (Mint16signed | Mint16unsigned) => true
  | Mint32, Mint32 => true
  | Mfloat32, Mfloat32 => true
  | Mint64, Mint64 => true
  | Mfloat64, Mfloat64 => true
  | Many32, Many32 => true
  | Many64, Many64 => true
  | _, _ => false
  end.Definition ablock_load_anywhere (chunk: memory_chunk) (ab: ablock) : aval :=
  vnormalize chunk (Ifptr ab.(ab_summary)).Function inval_after (lo: Z) (hi: Z) (c: ZTree.t acontent) { wf (Zwf lo) hi } : ZTree.t acontent :=
  if zle lo hi
  then inval_after lo (hi - 1) (ZTree.remove hi c)
  else c.Function inval_before (hi: Z) (lo: Z) (c: ZTree.t acontent) { wf (Zwf_up hi) lo } : ZTree.t acontent :=
  if zlt lo hi
  then inval_before hi (lo + 1) (inval_if hi lo c)
  else c.Definition ablock_store (chunk: memory_chunk) (ab: ablock) (i: Z) (av: aval) : ablock :=
  {| ab_contents :=
       ZTree.set i (ACval chunk av)
         (inval_before i (i - 7)
            (inval_after (i + 1) (i + size_chunk chunk - 1) ab.(ab_contents)));
     ab_summary :=
       vplub av ab.(ab_summary) |}.Definition ablock_store_anywhere (chunk: memory_chunk) (ab: ablock) (av: aval) : ablock :=
  ablock_init (vplub av ab.(ab_summary)).Definition ablock_loadbytes (ab: ablock) : aptr := ab.(ab_summary).Definition ablock_storebytes (ab: ablock) (p: aptr) (ofs: Z) (sz: Z) :=
  {| ab_contents :=
       inval_before ofs (ofs - 7)
         (inval_after ofs (ofs + sz - 1) ab.(ab_contents));
     ab_summary :=
       plub p ab.(ab_summary) |}.Definition ablock_storebytes_anywhere (ab: ablock) (p: aptr) :=
  ablock_init (plub p ab.(ab_summary)).Definition smatch (m: mem) (b: block) (p: aptr) : Prop :=
  (forall chunk ofs v, Mem.load chunk m b ofs = Some v -> vmatch v (Ifptr p))
/\(forall ofs b' ofs' q i, Mem.loadbytes m b ofs 1 = Some (Fragment (Vptr b' ofs') q i :: nil) -> pmatch b' ofs' p).Remark loadbytes_load_ext:
  forall b m m',
  (forall ofs n bytes, Mem.loadbytes m' b ofs n = Some bytes -> n >= 0 -> Mem.loadbytes m b ofs n = Some bytes) ->
  forall chunk ofs v, Mem.load chunk m' b ofs = Some v -> Mem.load chunk m b ofs = Some v.

Lemma smatch_ext: forall m b p m', smatch m b p -> (forall ofs n bytes, Mem.loadbytes m' b ofs n = Some bytes -> n >= 0 -> Mem.loadbytes m b ofs n = Some bytes) -> smatch m' b p.