infer_clone/infer/src/biabduction/Abs.ml

(*
 * Copyright (c) 2009-2013, Monoidics ltd.
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *)

open! IStd

(** Implementation of Abstraction Functions *)

module L = Logging

(** {2 Abstraction} *)

type rule =
  { r_vars: Ident.t list
  ; r_root: Match.hpred_pat
  ; r_sigma: Match.hpred_pat list
  ; (* sigma should be in a specific order *)
    r_new_sigma: Sil.hpred list
  ; r_new_pi: Prop.normal Prop.t -> Prop.normal Prop.t -> Sil.exp_subst -> Sil.atom list
  ; r_condition: Prop.normal Prop.t -> Sil.exp_subst -> bool }

let sigma_rewrite tenv p r : Prop.normal Prop.t option =
  match Match.prop_match_with_impl tenv p r.r_condition r.r_vars r.r_root r.r_sigma with
  | None ->
      None
  | Some (sub, p_leftover) ->
      if not (r.r_condition p_leftover sub) then None
      else
        let res_pi = r.r_new_pi p p_leftover sub in
        let res_sigma = Prop.sigma_sub (`Exp sub) r.r_new_sigma in
        let p_with_res_pi = List.fold ~f:(Prop.prop_atom_and tenv) ~init:p_leftover res_pi in
        let p_new = Prop.prop_sigma_star p_with_res_pi res_sigma in
        Some (Prop.normalize tenv p_new)


(******************** Start of SLL abstraction rules  *****************)
let create_fresh_primeds_ls para =
  let id_base = Ident.create_fresh Ident.kprimed in
  let id_next = Ident.create_fresh Ident.kprimed in
  let id_end = Ident.create_fresh Ident.kprimed in
  let ids_shared =
    let svars = para.Sil.svars in
    let f _ = Ident.create_fresh Ident.kprimed in
    List.map ~f svars
  in
  let ids_tuple = (id_base, id_next, id_end, ids_shared) in
  let exp_base = Exp.Var id_base in
  let exp_next = Exp.Var id_next in
  let exp_end = Exp.Var id_end in
  let exps_shared = List.map ~f:(fun id -> Exp.Var id) ids_shared in
  let exps_tuple = (exp_base, exp_next, exp_end, exps_shared) in
  (ids_tuple, exps_tuple)


let create_condition_ls ids_private id_base p_leftover (inst : Sil.exp_subst) =
  let insts_of_private_ids, insts_of_public_ids, inst_of_base =
    let f id' = List.exists ~f:(fun id'' -> Ident.equal id' id'') ids_private in
    let inst_private, inst_public = Sil.sub_domain_partition f inst in
    let insts_of_public_ids = Sil.sub_range inst_public in
    let inst_of_base =
      try Sil.sub_find (Ident.equal id_base) inst_public with Caml.Not_found -> assert false
    in
    let insts_of_private_ids = Sil.sub_range inst_private in
    (insts_of_private_ids, insts_of_public_ids, inst_of_base)
  in
  (*
  let fav_inst_of_base = Sil.exp_fav_list inst_of_base in
  L.out "@[.... application of condition ....@\n@.";
  L.out "@[<4>  private ids : %a@\n@." pp_exp_list insts_of_private_ids;
  L.out "@[<4>  public ids : %a@\n@." pp_exp_list insts_of_public_ids;
  *)
  Exp.program_vars inst_of_base |> Sequence.is_empty
  && List.for_all ~f:(fun e -> Exp.program_vars e |> Sequence.is_empty) insts_of_private_ids
  &&
  let fav_insts_of_private_ids =
    Sequence.of_list insts_of_private_ids
    |> Sequence.concat_map ~f:Exp.free_vars
    |> Sequence.memoize
  in
  (not (Sequence.exists fav_insts_of_private_ids ~f:Ident.is_normal))
  &&
  let fav_insts_of_private_ids = Ident.set_of_sequence fav_insts_of_private_ids in
  let intersects_fav_insts_of_private_ids s =
    Sequence.exists s ~f:(fun id -> Ident.Set.mem id fav_insts_of_private_ids)
  in
  (* [fav_insts_of_private_ids] does not intersect the free vars in [p_leftover.sigma] *)
  Prop.sigma_free_vars p_leftover.Prop.sigma |> Fn.non intersects_fav_insts_of_private_ids
  && (* [fav_insts_of_private_ids] does not intersect the free vars in [insts_of_public_ids] *)
     List.for_all insts_of_public_ids ~f:(fun e ->
         Exp.free_vars e |> Fn.non intersects_fav_insts_of_private_ids )


let mk_rule_ptspts_ls tenv impl_ok1 impl_ok2 (para : Sil.hpara) =
  let ids_tuple, exps_tuple = create_fresh_primeds_ls para in
  let id_base, id_next, id_end, ids_shared = ids_tuple in
  let exp_base, exp_next, exp_end, exps_shared = exps_tuple in
  let ids_exist_fst, para_fst = Sil.hpara_instantiate para exp_base exp_next exps_shared in
  let para_fst_start, para_fst_rest =
    let mark_impl_flag hpred = {Match.hpred; Match.flag= impl_ok1} in
    match para_fst with
    | [] ->
        L.internal_error "@\n@\nERROR (Empty Para): %a@\n@." (Sil.pp_hpara Pp.text) para ;
        assert false
    | hpred :: hpreds ->
        let hpat = mark_impl_flag hpred in
        let hpats = List.map ~f:mark_impl_flag hpreds in
        (hpat, hpats)
  in
  let ids_exist_snd, para_snd =
    let mark_impl_flag hpred = {Match.hpred; Match.flag= impl_ok2} in
    let ids, para_body = Sil.hpara_instantiate para exp_next exp_end exps_shared in
    let para_body_hpats = List.map ~f:mark_impl_flag para_body in
    (ids, para_body_hpats)
  in
  let lseg_res = Prop.mk_lseg tenv Sil.Lseg_NE para exp_base exp_end exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = id_next :: (ids_exist_fst @ ids_exist_snd) in
    create_condition_ls ids_private id_base
  in
  { r_vars= (id_base :: id_next :: id_end :: ids_shared) @ ids_exist_fst @ ids_exist_snd
  ; r_root= para_fst_start
  ; r_sigma= para_fst_rest @ para_snd
  ; r_new_sigma= [lseg_res]
  ; r_new_pi= gen_pi_res
  ; r_condition= condition }


let mk_rule_ptsls_ls tenv k2 impl_ok1 impl_ok2 para =
  let ids_tuple, exps_tuple = create_fresh_primeds_ls para in
  let id_base, id_next, id_end, ids_shared = ids_tuple in
  let exp_base, exp_next, exp_end, exps_shared = exps_tuple in
  let ids_exist, para_inst = Sil.hpara_instantiate para exp_base exp_next exps_shared in
  let para_inst_start, para_inst_rest =
    match para_inst with
    | [] ->
        L.internal_error "@\n@\nERROR (Empty Para): %a@\n@." (Sil.pp_hpara Pp.text) para ;
        assert false
    | hpred :: hpreds ->
        let allow_impl hpred = {Match.hpred; Match.flag= impl_ok1} in
        (allow_impl hpred, List.map ~f:allow_impl hpreds)
  in
  let lseg_pat =
    {Match.hpred= Prop.mk_lseg tenv k2 para exp_next exp_end exps_shared; Match.flag= impl_ok2}
  in
  let lseg_res = Prop.mk_lseg tenv Sil.Lseg_NE para exp_base exp_end exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = id_next :: ids_exist in
    create_condition_ls ids_private id_base
  in
  { r_vars= (id_base :: id_next :: id_end :: ids_shared) @ ids_exist
  ; r_root= para_inst_start
  ; r_sigma= para_inst_rest @ [lseg_pat]
  ; r_new_pi= gen_pi_res
  ; r_new_sigma= [lseg_res]
  ; r_condition= condition }


let mk_rule_lspts_ls tenv k1 impl_ok1 impl_ok2 para =
  let ids_tuple, exps_tuple = create_fresh_primeds_ls para in
  let id_base, id_next, id_end, ids_shared = ids_tuple in
  let exp_base, exp_next, exp_end, exps_shared = exps_tuple in
  let lseg_pat =
    {Match.hpred= Prop.mk_lseg tenv k1 para exp_base exp_next exps_shared; Match.flag= impl_ok1}
  in
  let ids_exist, para_inst_pat =
    let ids, para_body = Sil.hpara_instantiate para exp_next exp_end exps_shared in
    let allow_impl hpred = {Match.hpred; Match.flag= impl_ok2} in
    let para_body_pat = List.map ~f:allow_impl para_body in
    (ids, para_body_pat)
  in
  let lseg_res = Prop.mk_lseg tenv Sil.Lseg_NE para exp_base exp_end exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = id_next :: ids_exist in
    create_condition_ls ids_private id_base
  in
  { r_vars= (id_base :: id_next :: id_end :: ids_shared) @ ids_exist
  ; r_root= lseg_pat
  ; r_sigma= para_inst_pat
  ; r_new_sigma= [lseg_res]
  ; r_new_pi= gen_pi_res
  ; r_condition= condition }


let lseg_kind_add k1 k2 =
  match (k1, k2) with
  | Sil.Lseg_NE, Sil.Lseg_NE | Sil.Lseg_NE, Sil.Lseg_PE | Sil.Lseg_PE, Sil.Lseg_NE ->
      Sil.Lseg_NE
  | Sil.Lseg_PE, Sil.Lseg_PE ->
      Sil.Lseg_PE


let mk_rule_lsls_ls tenv k1 k2 impl_ok1 impl_ok2 para =
  let ids_tuple, exps_tuple = create_fresh_primeds_ls para in
  let id_base, id_next, id_end, ids_shared = ids_tuple in
  let exp_base, exp_next, exp_end, exps_shared = exps_tuple in
  let lseg_fst_pat =
    {Match.hpred= Prop.mk_lseg tenv k1 para exp_base exp_next exps_shared; Match.flag= impl_ok1}
  in
  let lseg_snd_pat =
    {Match.hpred= Prop.mk_lseg tenv k2 para exp_next exp_end exps_shared; Match.flag= impl_ok2}
  in
  let k_res = lseg_kind_add k1 k2 in
  let lseg_res = Prop.mk_lseg tenv k_res para exp_base exp_end exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) =
    []
    (*
  let inst_base, inst_next, inst_end =
  let find x = sub_find (equal x) inst in
  try
  (find id_base, find id_next, find id_end)
  with Not_found -> assert false in
  let spooky_case _ =
  (equal_lseg_kind Sil.Lseg_PE k_res)
  && (check_allocatedness p_leftover inst_end)
  && ((check_disequal p_start inst_base inst_next)
  || (check_disequal p_start inst_next inst_end)) in
  let obvious_case _ =
  check_disequal p_start inst_base inst_end &&
  not (check_disequal p_leftover inst_base inst_end) in
  if not (spooky_case () || obvious_case ()) then []
  else [Aneq(inst_base, inst_end)]
  *)
  in
  let condition =
    let ids_private = [id_next] in
    create_condition_ls ids_private id_base
  in
  { r_vars= id_base :: id_next :: id_end :: ids_shared
  ; r_root= lseg_fst_pat
  ; r_sigma= [lseg_snd_pat]
  ; r_new_sigma= [lseg_res]
  ; r_new_pi= gen_pi_res
  ; r_condition= condition }


let mk_rules_for_sll tenv (para : Sil.hpara) : rule list =
  if not Config.nelseg then
    let pts_pts = mk_rule_ptspts_ls tenv true true para in
    let pts_pels = mk_rule_ptsls_ls tenv Sil.Lseg_PE true false para in
    let pels_pts = mk_rule_lspts_ls tenv Sil.Lseg_PE false true para in
    let pels_nels = mk_rule_lsls_ls tenv Sil.Lseg_PE Sil.Lseg_NE false false para in
    let nels_pels = mk_rule_lsls_ls tenv Sil.Lseg_NE Sil.Lseg_PE false false para in
    let pels_pels = mk_rule_lsls_ls tenv Sil.Lseg_PE Sil.Lseg_PE false false para in
    [pts_pts; pts_pels; pels_pts; pels_nels; nels_pels; pels_pels]
  else
    let pts_pts = mk_rule_ptspts_ls tenv true true para in
    let pts_nels = mk_rule_ptsls_ls tenv Sil.Lseg_NE true false para in
    let nels_pts = mk_rule_lspts_ls tenv Sil.Lseg_NE false true para in
    let nels_nels = mk_rule_lsls_ls tenv Sil.Lseg_NE Sil.Lseg_NE false false para in
    [pts_pts; pts_nels; nels_pts; nels_nels]


(******************  End of SLL abstraction rules ******************)
(******************  Start of DLL abstraction rules  ******************)
let create_condition_dll = create_condition_ls

let mk_rule_ptspts_dll tenv impl_ok1 impl_ok2 para =
  let id_iF = Ident.create_fresh Ident.kprimed in
  let id_iF' = Ident.create_fresh Ident.kprimed in
  let id_oB = Ident.create_fresh Ident.kprimed in
  let id_oF = Ident.create_fresh Ident.kprimed in
  let ids_shared =
    let svars = para.Sil.svars_dll in
    let f _ = Ident.create_fresh Ident.kprimed in
    List.map ~f svars
  in
  let exp_iF = Exp.Var id_iF in
  let exp_iF' = Exp.Var id_iF' in
  let exp_oB = Exp.Var id_oB in
  let exp_oF = Exp.Var id_oF in
  let exps_shared = List.map ~f:(fun id -> Exp.Var id) ids_shared in
  let ids_exist_fst, para_fst = Sil.hpara_dll_instantiate para exp_iF exp_oB exp_iF' exps_shared in
  let para_fst_start, para_fst_rest =
    let mark_impl_flag hpred = {Match.hpred; Match.flag= impl_ok1} in
    match para_fst with
    | [] ->
        L.internal_error "@\n@\nERROR (Empty DLL Para): %a@\n@." (Sil.pp_hpara_dll Pp.text) para ;
        assert false
    | hpred :: hpreds ->
        let hpat = mark_impl_flag hpred in
        let hpats = List.map ~f:mark_impl_flag hpreds in
        (hpat, hpats)
  in
  let ids_exist_snd, para_snd =
    let mark_impl_flag hpred = {Match.hpred; Match.flag= impl_ok2} in
    let ids, para_body = Sil.hpara_dll_instantiate para exp_iF' exp_iF exp_oF exps_shared in
    let para_body_hpats = List.map ~f:mark_impl_flag para_body in
    (ids, para_body_hpats)
  in
  let dllseg_res = Prop.mk_dllseg tenv Sil.Lseg_NE para exp_iF exp_oB exp_oF exp_iF' exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    (* for the case of ptspts since iF'=iB therefore iF' cannot be private*)
    let ids_private = ids_exist_fst @ ids_exist_snd in
    create_condition_dll ids_private id_iF
  in
  (*
  L.out "r_root/para_fst_start=%a @.@." pp_hpat para_fst_start;
  L.out "para_fst_rest=%a @.@." pp_hpat_list para_fst_rest;
  L.out "para_snd=%a @.@." pp_hpat_list para_snd;
  L.out "dllseg_res=%a @.@." pp_hpred dllseg_res;
  *)
  { r_vars= (id_iF :: id_oB :: id_iF' :: id_oF :: ids_shared) @ ids_exist_fst @ ids_exist_snd
  ; r_root= para_fst_start
  ; r_sigma= para_fst_rest @ para_snd
  ; r_new_sigma= [dllseg_res]
  ; r_new_pi= gen_pi_res
  ; r_condition= condition }


let mk_rule_ptsdll_dll tenv k2 impl_ok1 impl_ok2 para =
  let id_iF = Ident.create_fresh Ident.kprimed in
  let id_iF' = Ident.create_fresh Ident.kprimed in
  let id_oB = Ident.create_fresh Ident.kprimed in
  let id_oF = Ident.create_fresh Ident.kprimed in
  let id_iB = Ident.create_fresh Ident.kprimed in
  let ids_shared =
    let svars = para.Sil.svars_dll in
    let f _ = Ident.create_fresh Ident.kprimed in
    List.map ~f svars
  in
  let exp_iF = Exp.Var id_iF in
  let exp_iF' = Exp.Var id_iF' in
  let exp_oB = Exp.Var id_oB in
  let exp_oF = Exp.Var id_oF in
  let exp_iB = Exp.Var id_iB in
  let exps_shared = List.map ~f:(fun id -> Exp.Var id) ids_shared in
  let ids_exist, para_inst = Sil.hpara_dll_instantiate para exp_iF exp_oB exp_iF' exps_shared in
  let para_inst_start, para_inst_rest =
    match para_inst with
    | [] ->
        assert false
    | hpred :: hpreds ->
        let allow_impl hpred = {Match.hpred; Match.flag= impl_ok1} in
        (allow_impl hpred, List.map ~f:allow_impl hpreds)
  in
  let dllseg_pat =
    { Match.hpred= Prop.mk_dllseg tenv k2 para exp_iF' exp_iF exp_oF exp_iB exps_shared
    ; Match.flag= impl_ok2 }
  in
  let dllseg_res = Prop.mk_dllseg tenv Sil.Lseg_NE para exp_iF exp_oB exp_oF exp_iB exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = id_iF' :: ids_exist in
    create_condition_dll ids_private id_iF
  in
  { r_vars= (id_iF :: id_oB :: id_iF' :: id_oF :: id_iB :: ids_shared) @ ids_exist
  ; r_root= para_inst_start
  ; r_sigma= para_inst_rest @ [dllseg_pat]
  ; r_new_pi= gen_pi_res
  ; r_new_sigma= [dllseg_res]
  ; r_condition= condition }


let mk_rule_dllpts_dll tenv k1 impl_ok1 impl_ok2 para =
  let id_iF = Ident.create_fresh Ident.kprimed in
  let id_iF' = Ident.create_fresh Ident.kprimed in
  let id_oB = Ident.create_fresh Ident.kprimed in
  let id_oB' = Ident.create_fresh Ident.kprimed in
  let id_oF = Ident.create_fresh Ident.kprimed in
  let ids_shared =
    let svars = para.Sil.svars_dll in
    let f _ = Ident.create_fresh Ident.kprimed in
    List.map ~f svars
  in
  let exp_iF = Exp.Var id_iF in
  let exp_iF' = Exp.Var id_iF' in
  let exp_oB = Exp.Var id_oB in
  let exp_oB' = Exp.Var id_oB' in
  let exp_oF = Exp.Var id_oF in
  let exps_shared = List.map ~f:(fun id -> Exp.Var id) ids_shared in
  let ids_exist, para_inst = Sil.hpara_dll_instantiate para exp_iF' exp_oB' exp_oF exps_shared in
  let para_inst_pat =
    let allow_impl hpred = {Match.hpred; Match.flag= impl_ok2} in
    List.map ~f:allow_impl para_inst
  in
  let dllseg_pat =
    { Match.hpred= Prop.mk_dllseg tenv k1 para exp_iF exp_oB exp_iF' exp_oB' exps_shared
    ; Match.flag= impl_ok1 }
  in
  let dllseg_res = Prop.mk_dllseg tenv Sil.Lseg_NE para exp_iF exp_oB exp_oF exp_iF' exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = id_oB' :: ids_exist in
    create_condition_dll ids_private id_iF
  in
  { r_vars= (id_iF :: id_oB :: id_iF' :: id_oB' :: id_oF :: ids_shared) @ ids_exist
  ; r_root= dllseg_pat
  ; r_sigma= para_inst_pat
  ; r_new_pi= gen_pi_res
  ; r_new_sigma= [dllseg_res]
  ; r_condition= condition }


let mk_rule_dlldll_dll tenv k1 k2 impl_ok1 impl_ok2 para =
  let id_iF = Ident.create_fresh Ident.kprimed in
  let id_iF' = Ident.create_fresh Ident.kprimed in
  let id_oB = Ident.create_fresh Ident.kprimed in
  let id_oB' = Ident.create_fresh Ident.kprimed in
  let id_oF = Ident.create_fresh Ident.kprimed in
  let id_iB = Ident.create_fresh Ident.kprimed in
  let ids_shared =
    let svars = para.Sil.svars_dll in
    let f _ = Ident.create_fresh Ident.kprimed in
    List.map ~f svars
  in
  let exp_iF = Exp.Var id_iF in
  let exp_iF' = Exp.Var id_iF' in
  let exp_oB = Exp.Var id_oB in
  let exp_oB' = Exp.Var id_oB' in
  let exp_oF = Exp.Var id_oF in
  let exp_iB = Exp.Var id_iB in
  let exps_shared = List.map ~f:(fun id -> Exp.Var id) ids_shared in
  let lseg_fst_pat =
    { Match.hpred= Prop.mk_dllseg tenv k1 para exp_iF exp_oB exp_iF' exp_oB' exps_shared
    ; Match.flag= impl_ok1 }
  in
  let lseg_snd_pat =
    { Match.hpred= Prop.mk_dllseg tenv k2 para exp_iF' exp_oB' exp_oF exp_iB exps_shared
    ; Match.flag= impl_ok2 }
  in
  let k_res = lseg_kind_add k1 k2 in
  let lseg_res = Prop.mk_dllseg tenv k_res para exp_iF exp_oB exp_oF exp_iB exps_shared in
  let gen_pi_res _ _ (_ : Sil.exp_subst) = [] in
  let condition =
    let ids_private = [id_iF'; id_oB'] in
    create_condition_dll ids_private id_iF
  in
  { r_vars= id_iF :: id_iF' :: id_oB :: id_oB' :: id_oF :: id_iB :: ids_shared
  ; r_root= lseg_fst_pat
  ; r_sigma= [lseg_snd_pat]
  ; r_new_sigma= [lseg_res]
  ; r_new_pi= gen_pi_res
  ; r_condition= condition }


let mk_rules_for_dll tenv (para : Sil.hpara_dll) : rule list =
  if not Config.nelseg then
    let pts_pts = mk_rule_ptspts_dll tenv true true para in
    let pts_pedll = mk_rule_ptsdll_dll tenv Sil.Lseg_PE true false para in
    let pedll_pts = mk_rule_dllpts_dll tenv Sil.Lseg_PE false true para in
    let pedll_nedll = mk_rule_dlldll_dll tenv Sil.Lseg_PE Sil.Lseg_NE false false para in
    let nedll_pedll = mk_rule_dlldll_dll tenv Sil.Lseg_NE Sil.Lseg_PE false false para in
    let pedll_pedll = mk_rule_dlldll_dll tenv Sil.Lseg_PE Sil.Lseg_PE false false para in
    [pts_pts; pts_pedll; pedll_pts; pedll_nedll; nedll_pedll; pedll_pedll]
  else
    let ptspts_dll = mk_rule_ptspts_dll tenv true true para in
    let ptsdll_dll = mk_rule_ptsdll_dll tenv Sil.Lseg_NE true false para in
    let dllpts_dll = mk_rule_dllpts_dll tenv Sil.Lseg_NE false true para in
    let dlldll_dll = mk_rule_dlldll_dll tenv Sil.Lseg_NE Sil.Lseg_NE false false para in
    [ptspts_dll; ptsdll_dll; dllpts_dll; dlldll_dll]


(******************  End of DLL abstraction rules  ******************)
(******************  Start of Predicate Discovery  ******************)
let typ_get_recursive_flds tenv typ_exp =
  let filter typ (_, (t : Typ.t), _) =
    match t.desc with
    | Tstruct _ | Tint _ | Tfloat _ | Tvoid | Tfun _ | TVar _ ->
        false
    | Tptr (({desc= Tstruct _} as typ'), _) ->
        Typ.equal typ' typ
    | Tptr _ | Tarray _ ->
        false
  in
  match typ_exp with
  | Exp.Sizeof {typ} -> (
    match typ.desc with
    | Tstruct name -> (
      match Tenv.lookup tenv name with
      | Some {fields} ->
          List.map ~f:fst3 (List.filter ~f:(filter typ) fields)
      | None ->
          L.(debug Analysis Quiet)
            "@\ntyp_get_recursive_flds: unexpected %a unknown struct type: %a@." Exp.pp typ_exp
            Typ.Name.pp name ;
          [] (* ToDo: assert false *) )
    | Tint _ | Tvoid | Tfun _ | Tptr _ | Tfloat _ | Tarray _ | TVar _ ->
        [] )
  | Exp.Var _ ->
      [] (* type of |-> not known yet *)
  | Exp.Const _ ->
      []
  | _ ->
      L.internal_error "@\ntyp_get_recursive_flds: unexpected type expr: %a@." Exp.pp typ_exp ;
      assert false


let discover_para_roots tenv p root1 next1 root2 next2 : Sil.hpara option =
  let eq_arg1 = Exp.equal root1 next1 in
  let eq_arg2 = Exp.equal root2 next2 in
  let precondition_check = (not eq_arg1) && not eq_arg2 in
  if not precondition_check then None
  else
    let corres = [(next1, next2)] in
    let todos = [(root1, root2)] in
    let sigma = p.Prop.sigma in
    match Match.find_partial_iso tenv (Prover.check_equal tenv p) corres todos sigma with
    | None ->
        None
    | Some (new_corres, new_sigma1, _, _) ->
        let hpara, _ = Match.hpara_create tenv new_corres new_sigma1 root1 next1 in
        Some hpara


let discover_para_dll_roots tenv p root1 blink1 flink1 root2 blink2 flink2 : Sil.hpara_dll option =
  let eq_arg1 = Exp.equal root1 blink1 in
  let eq_arg1' = Exp.equal root1 flink1 in
  let eq_arg2 = Exp.equal root2 blink2 in
  let eq_arg2' = Exp.equal root2 flink2 in
  let precondition_check = not (eq_arg1 || eq_arg1' || eq_arg2 || eq_arg2') in
  if not precondition_check then None
  else
    let corres = [(blink1, blink2); (flink1, flink2)] in
    let todos = [(root1, root2)] in
    let sigma = p.Prop.sigma in
    match Match.find_partial_iso tenv (Prover.check_equal tenv p) corres todos sigma with
    | None ->
        None
    | Some (new_corres, new_sigma1, _, _) ->
        let hpara_dll, _ = Match.hpara_dll_create tenv new_corres new_sigma1 root1 blink1 flink1 in
        Some hpara_dll


let discover_para_candidates tenv p =
  let edges = ref [] in
  let add_edge edg = edges := edg :: !edges in
  let get_edges_strexp rec_flds root se =
    let is_rec_fld fld = List.exists ~f:(Typ.Fieldname.equal fld) rec_flds in
    match se with
    | Sil.Eexp _ | Sil.Earray _ ->
        ()
    | Sil.Estruct (fsel, _) ->
        let fsel' = List.filter ~f:(fun (fld, _) -> is_rec_fld fld) fsel in
        let process (_, nextse) =
          match nextse with Sil.Eexp (next, _) -> add_edge (root, next) | _ -> assert false
        in
        List.iter ~f:process fsel'
  in
  let rec get_edges_sigma = function
    | [] ->
        ()
    | Sil.Hlseg _ :: sigma_rest | Sil.Hdllseg _ :: sigma_rest ->
        get_edges_sigma sigma_rest
    | Sil.Hpointsto (root, se, te) :: sigma_rest ->
        let rec_flds = typ_get_recursive_flds tenv te in
        get_edges_strexp rec_flds root se ; get_edges_sigma sigma_rest
  in
  let rec find_all_consecutive_edges found edges_seen = function
    | [] ->
        List.rev found
    | (e1, e2) :: edges_notseen ->
        let edges_others = List.rev_append edges_seen edges_notseen in
        let edges_matched = List.filter ~f:(fun (e1', _) -> Exp.equal e2 e1') edges_others in
        let new_found =
          let f found_acc (_, e3) = (e1, e2, e3) :: found_acc in
          List.fold ~f ~init:found edges_matched
        in
        let new_edges_seen = (e1, e2) :: edges_seen in
        find_all_consecutive_edges new_found new_edges_seen edges_notseen
  in
  let sigma = p.Prop.sigma in
  get_edges_sigma sigma ;
  find_all_consecutive_edges [] [] !edges


let discover_para_dll_candidates tenv p =
  let edges = ref [] in
  let add_edge edg = edges := edg :: !edges in
  let get_edges_strexp rec_flds root se =
    let is_rec_fld fld = List.exists ~f:(Typ.Fieldname.equal fld) rec_flds in
    match se with
    | Sil.Eexp _ | Sil.Earray _ ->
        ()
    | Sil.Estruct (fsel, _) ->
        let fsel' = List.rev_filter ~f:(fun (fld, _) -> is_rec_fld fld) fsel in
        let convert_to_exp acc (_, se) =
          match se with Sil.Eexp (e, _) -> e :: acc | _ -> assert false
        in
        let links = List.fold ~f:convert_to_exp ~init:[] fsel' in
        let rec iter_pairs = function
          | [] ->
              ()
          | x :: l ->
              List.iter ~f:(fun y -> add_edge (root, x, y)) l ;
              iter_pairs l
        in
        iter_pairs links
  in
  let rec get_edges_sigma = function
    | [] ->
        ()
    | Sil.Hlseg _ :: sigma_rest | Sil.Hdllseg _ :: sigma_rest ->
        get_edges_sigma sigma_rest
    | Sil.Hpointsto (root, se, te) :: sigma_rest ->
        let rec_flds = typ_get_recursive_flds tenv te in
        get_edges_strexp rec_flds root se ; get_edges_sigma sigma_rest
  in
  let rec find_all_consecutive_edges found edges_seen = function
    | [] ->
        List.rev found
    | (iF, blink, flink) :: edges_notseen ->
        let edges_others = List.rev_append edges_seen edges_notseen in
        let edges_matched = List.filter ~f:(fun (e1', _, _) -> Exp.equal flink e1') edges_others in
        let new_found =
          let f found_acc (_, _, flink2) = (iF, blink, flink, flink2) :: found_acc in
          List.fold ~f ~init:found edges_matched
        in
        let new_edges_seen = (iF, blink, flink) :: edges_seen in
        find_all_consecutive_edges new_found new_edges_seen edges_notseen
  in
  let sigma = p.Prop.sigma in
  get_edges_sigma sigma ;
  find_all_consecutive_edges [] [] !edges


let discover_para tenv p =
  let candidates = discover_para_candidates tenv p in
  let already_defined para paras =
    List.exists ~f:(fun para' -> Match.hpara_iso tenv para para') paras
  in
  let f paras (root, next, out) =
    match discover_para_roots tenv p root next next out with
    | None ->
        paras
    | Some para ->
        if already_defined para paras then paras else para :: paras
  in
  List.fold ~f ~init:[] candidates


let discover_para_dll tenv p =
  (*
  L.out "@[.... Called discover_dll para ...@.";
  L.out "@[<4>  PROP : %a@\n@." pp_prop p;
  *)
  let candidates = discover_para_dll_candidates tenv p in
  let already_defined para paras =
    List.exists ~f:(fun para' -> Match.hpara_dll_iso tenv para para') paras
  in
  let f paras (iF, oB, iF', oF) =
    match discover_para_dll_roots tenv p iF oB iF' iF' iF oF with
    | None ->
        paras
    | Some para ->
        if already_defined para paras then paras else para :: paras
  in
  List.fold ~f ~init:[] candidates


(******************  End of Predicate Discovery  ******************)
(****************** Start of the ADT abs_rules ******************)

(** Type of parameter for abstraction rules *)
type para_ty = SLL of Sil.hpara | DLL of Sil.hpara_dll

(** Rule set: a list of rules of a given type *)
type rule_set = para_ty * rule list

type rules = rule_set list

module Global = struct
  let current_rules : rules ref = ref []
end

let get_current_rules () = !Global.current_rules

let set_current_rules rules = Global.current_rules := rules

let reset_current_rules () = Global.current_rules := []

let eqs_sub subst eqs =
  List.map ~f:(fun (e1, e2) -> (Sil.exp_sub (`Exp subst) e1, Sil.exp_sub (`Exp subst) e2)) eqs


let eqs_solve ids_in eqs_in =
  let rec solve (sub : Sil.exp_subst) (eqs : (Exp.t * Exp.t) list) : Sil.exp_subst option =
    let do_default id e eqs_rest =
      if not (List.exists ~f:(fun id' -> Ident.equal id id') ids_in) then None
      else
        let sub' =
          match Sil.extend_sub sub id e with
          | None ->
              L.internal_error "@\n@\nERROR : Buggy Implementation.@\n@." ;
              assert false
          | Some sub' ->
              sub'
        in
        let eqs_rest' = eqs_sub sub' eqs_rest in
        solve sub' eqs_rest'
    in
    match eqs with
    | [] ->
        Some sub
    | (e1, e2) :: eqs_rest when Exp.equal e1 e2 ->
        solve sub eqs_rest
    | (Exp.Var id1, (Exp.Const _ as e2)) :: eqs_rest ->
        do_default id1 e2 eqs_rest
    | ((Exp.Const _ as e1), (Exp.Var _ as e2)) :: eqs_rest ->
        solve sub ((e2, e1) :: eqs_rest)
    | ((Exp.Var id1 as e1), (Exp.Var id2 as e2)) :: eqs_rest ->
        let n = Ident.compare id1 id2 in
        if Int.equal n 0 then solve sub eqs_rest
        else if n > 0 then solve sub ((e2, e1) :: eqs_rest)
        else do_default id1 e2 eqs_rest
    | _ :: _ ->
        None
  in
  let compute_ids sub =
    let sub_list = Sil.sub_to_list sub in
    let sub_dom = List.map ~f:fst sub_list in
    let filter id = not (List.exists ~f:(fun id' -> Ident.equal id id') sub_dom) in
    List.filter ~f:filter ids_in
  in
  match solve Sil.exp_sub_empty eqs_in with None -> None | Some sub -> Some (compute_ids sub, sub)


let sigma_special_cases_eqs sigma =
  let rec f ids_acc eqs_acc sigma_acc = function
    | [] ->
        [(List.rev ids_acc, List.rev eqs_acc, List.rev sigma_acc)]
    | (Sil.Hpointsto _ as hpred) :: sigma_rest ->
        f ids_acc eqs_acc (hpred :: sigma_acc) sigma_rest
    | (Sil.Hlseg (_, para, e1, e2, es) as hpred) :: sigma_rest ->
        let empty_case = f ids_acc ((e1, e2) :: eqs_acc) sigma_acc sigma_rest in
        let pointsto_case =
          let eids, para_inst = Sil.hpara_instantiate para e1 e2 es in
          f (eids @ ids_acc) eqs_acc sigma_acc (para_inst @ sigma_rest)
        in
        let general_case = f ids_acc eqs_acc (hpred :: sigma_acc) sigma_rest in
        empty_case @ pointsto_case @ general_case
    | (Sil.Hdllseg (_, para, e1, e2, e3, e4, es) as hpred) :: sigma_rest ->
        let empty_case = f ids_acc ((e1, e3) :: (e2, e4) :: eqs_acc) sigma_acc sigma_rest in
        let pointsto_case =
          let eids, para_inst = Sil.hpara_dll_instantiate para e1 e2 e3 es in
          f (eids @ ids_acc) eqs_acc sigma_acc (para_inst @ sigma_rest)
        in
        let general_case = f ids_acc eqs_acc (hpred :: sigma_acc) sigma_rest in
        empty_case @ pointsto_case @ general_case
  in
  f [] [] [] sigma


let sigma_special_cases ids sigma : (Ident.t list * Sil.hpred list) list =
  let special_cases_eqs = sigma_special_cases_eqs sigma in
  let special_cases_rev =
    let f acc (eids_cur, eqs_cur, sigma_cur) =
      let ids_all = ids @ eids_cur in
      match eqs_solve ids_all eqs_cur with
      | None ->
          acc
      | Some (ids_res, sub) ->
          (ids_res, List.map ~f:(Sil.hpred_sub (`Exp sub)) sigma_cur) :: acc
    in
    List.fold ~f ~init:[] special_cases_eqs
  in
  List.rev special_cases_rev


let hpara_special_cases hpara : Sil.hpara list =
  let update_para (evars', body') = {hpara with Sil.evars= evars'; Sil.body= body'} in
  let special_cases = sigma_special_cases hpara.Sil.evars hpara.Sil.body in
  List.map ~f:update_para special_cases


let hpara_special_cases_dll hpara : Sil.hpara_dll list =
  let update_para (evars', body') = {hpara with Sil.evars_dll= evars'; Sil.body_dll= body'} in
  let special_cases = sigma_special_cases hpara.Sil.evars_dll hpara.Sil.body_dll in
  List.map ~f:update_para special_cases


let abs_rules_apply_rsets tenv (rsets : rule_set list) (p_in : Prop.normal Prop.t) :
    Prop.normal Prop.t =
  let apply_rule (changed, p) r =
    match sigma_rewrite tenv p r with
    | None ->
        (changed, p)
    | Some p' ->
        (*
    L.out "@[.... abstraction (rewritten in abs_rules) ....@.";
    L.out "@[<4>  PROP:%a@\n@." pp_prop p';
    *)
        (true, p')
  in
  let rec apply_rule_set p rset =
    let _, rules = rset in
    let changed, p' = List.fold ~f:apply_rule ~init:(false, p) rules in
    if changed then apply_rule_set p' rset else p'
  in
  List.fold ~f:apply_rule_set ~init:p_in rsets


let abs_rules_apply_lists tenv (p_in : Prop.normal Prop.t) : Prop.normal Prop.t =
  let new_rsets = ref [] in
  let old_rsets = get_current_rules () in
  let rec discover_then_abstract p =
    let closed_paras_sll, closed_paras_dll =
      let paras_sll = discover_para tenv p in
      let paras_dll = discover_para_dll tenv p in
      let closed_paras_sll = List.concat_map ~f:hpara_special_cases paras_sll in
      let closed_paras_dll = List.concat_map ~f:hpara_special_cases_dll paras_dll in
      (closed_paras_sll, closed_paras_dll)
    in
    let todo_paras_sll, todo_paras_dll =
      let eq_sll para rset =
        match rset with SLL para', _ -> Match.hpara_iso tenv para para' | _ -> false
      in
      let eq_dll para rset =
        match rset with DLL para', _ -> Match.hpara_dll_iso tenv para para' | _ -> false
      in
      let filter_sll para =
        (not (List.exists ~f:(eq_sll para) old_rsets))
        && not (List.exists ~f:(eq_sll para) !new_rsets)
      in
      let filter_dll para =
        (not (List.exists ~f:(eq_dll para) old_rsets))
        && not (List.exists ~f:(eq_dll para) !new_rsets)
      in
      let todo_paras_sll = List.filter ~f:filter_sll closed_paras_sll in
      let todo_paras_dll = List.filter ~f:filter_dll closed_paras_dll in
      (todo_paras_sll, todo_paras_dll)
    in
    let f_recurse () =
      let todo_rsets_sll =
        List.map ~f:(fun para -> (SLL para, mk_rules_for_sll tenv para)) todo_paras_sll
      in
      let todo_rsets_dll =
        List.map ~f:(fun para -> (DLL para, mk_rules_for_dll tenv para)) todo_paras_dll
      in
      new_rsets := !new_rsets @ todo_rsets_sll @ todo_rsets_dll ;
      let p' = abs_rules_apply_rsets tenv todo_rsets_sll p in
      let p'' = abs_rules_apply_rsets tenv todo_rsets_dll p' in
      discover_then_abstract p''
    in
    match (todo_paras_sll, todo_paras_dll) with [], [] -> p | _ -> f_recurse ()
  in
  let p1 = abs_rules_apply_rsets tenv old_rsets p_in in
  let p2 = discover_then_abstract p1 in
  let new_rules = old_rsets @ !new_rsets in
  set_current_rules new_rules ; p2


let abs_rules_apply tenv (p_in : Prop.normal Prop.t) : Prop.normal Prop.t =
  abs_rules_apply_lists tenv p_in


(****************** End of the ADT abs_rules ******************)
(****************** Start of Main Abstraction Functions ******************)
let abstract_pure_part tenv p ~(from_abstract_footprint : bool) =
  let do_pure pure =
    let pi_filtered =
      let sigma = p.Prop.sigma in
      let fav_sigma = Prop.sigma_free_vars sigma |> Ident.set_of_sequence in
      let fav_nonpure = Prop.non_pure_free_vars p |> Ident.set_of_sequence in
      (* vars in current and footprint sigma *)
      let filter atom =
        Sil.atom_free_vars atom
        |> Sequence.for_all ~f:(fun id ->
               if Ident.is_primed id then Ident.Set.mem id fav_sigma
               else if Ident.is_footprint id then Ident.Set.mem id fav_nonpure
               else true )
      in
      List.filter ~f:filter pure
    in
    let new_pure =
      List.fold
        ~f:(fun pi a ->
          match a with
          (* we only use Lt and Le because Gt and Ge are inserted in terms of Lt and Le. *)
          | Sil.Aeq (Exp.Const (Const.Cint i), Exp.BinOp (Binop.Lt, _, _))
          | Sil.Aeq (Exp.BinOp (Binop.Lt, _, _), Exp.Const (Const.Cint i))
          | Sil.Aeq (Exp.Const (Const.Cint i), Exp.BinOp (Binop.Le, _, _))
          | Sil.Aeq (Exp.BinOp (Binop.Le, _, _), Exp.Const (Const.Cint i))
            when IntLit.isone i ->
              a :: pi
          | Sil.Aeq (Exp.Var name, e) when not (Ident.is_primed name) -> (
            match e with Exp.Var _ | Exp.Const _ -> a :: pi | _ -> pi )
          | Sil.Aneq (Var _, _) | Sil.Apred (_, Var _ :: _) | Anpred (_, Var _ :: _) ->
              a :: pi
          | Sil.Aeq _ | Aneq _ | Apred _ | Anpred _ ->
              pi )
        ~init:[] pi_filtered
    in
    List.rev new_pure
  in
  let new_pure = do_pure (Prop.get_pure p) in
  let eprop' = Prop.set p ~pi:new_pure ~sub:Sil.exp_sub_empty in
  let eprop'' =
    if !Config.footprint && not from_abstract_footprint then
      let new_pi_footprint = do_pure p.Prop.pi_fp in
      Prop.set eprop' ~pi_fp:new_pi_footprint
    else eprop'
  in
  Prop.normalize tenv eprop''


(** Collect symbolic garbage from pi and sigma *)
let abstract_gc tenv p =
  let pi = p.Prop.pi in
  let p_without_pi = Prop.normalize tenv (Prop.set p ~pi:[]) in
  let fav_p_without_pi = Prop.free_vars p_without_pi |> Ident.set_of_sequence in
  (* let weak_filter atom =
     let fav_atom = atom_fav atom in
     IList.intersect compare fav_p_without_pi fav_atom in *)
  let check fav_seq =
    Sequence.is_empty fav_seq
    || (* non-empty intersection with [fav_p_without_pi] *)
       Sequence.exists fav_seq ~f:(fun id -> Ident.Set.mem id fav_p_without_pi)
  in
  let strong_filter = function
    | Sil.Aeq (e1, e2) | Sil.Aneq (e1, e2) ->
        check (Exp.free_vars e1) && check (Exp.free_vars e2)
    | (Sil.Apred _ | Anpred _) as a ->
        check (Sil.atom_free_vars a)
  in
  let new_pi = List.filter ~f:strong_filter pi in
  let prop = Prop.normalize tenv (Prop.set p ~pi:new_pi) in
  match Prop.prop_iter_create prop with
  | None ->
      prop
  | Some iter ->
      Prop.prop_iter_to_prop tenv (Prop.prop_iter_gc_fields iter)


(** find the id's in sigma reachable from the given roots *)
let sigma_reachable root_fav sigma =
  let reach_set = ref root_fav in
  let edges = ref [] in
  let do_hpred hpred =
    let hp_fav_set = Sil.hpred_free_vars hpred |> Ident.set_of_sequence in
    let add_entry e = edges := (e, hp_fav_set) :: !edges in
    List.iter ~f:add_entry (Sil.hpred_entries hpred)
  in
  List.iter ~f:do_hpred sigma ;
  let edge_fires (e, _) =
    match e with
    | Exp.Var id ->
        if Ident.is_primed id || Ident.is_footprint id then Ident.Set.mem id !reach_set else true
    | _ ->
        true
  in
  let rec apply_once edges_to_revisit edges_todo modified =
    match edges_todo with
    | [] ->
        (edges_to_revisit, modified)
    | edge :: edges_todo' ->
        if edge_fires edge then (
          reach_set := Ident.Set.union (snd edge) !reach_set ;
          apply_once edges_to_revisit edges_todo' true )
        else apply_once (edge :: edges_to_revisit) edges_todo' modified
  in
  let rec find_fixpoint edges_todo =
    let edges_to_revisit, modified = apply_once [] edges_todo false in
    if modified then find_fixpoint edges_to_revisit
  in
  find_fixpoint !edges ;
  (* L.d_str "reachable: ";
     Ident.Set.iter (fun id -> Sil.d_exp (Exp.Var id); L.d_str " ") !reach_set;
     L.d_ln (); *)
  !reach_set


let check_observer_is_unsubscribed_deallocation tenv prop e =
  let pvar_opt =
    match Attribute.get_resource tenv prop e with
    | Some (Apred (Aresource {ra_vpath= Some (Dpvar pvar)}, _)) ->
        Some pvar
    | _ ->
        None
  in
  let loc = State.get_loc_exn () in
  match Attribute.get_observer tenv prop e with
  | Some (Apred (Aobserver, _)) -> (
    match pvar_opt with
    | Some pvar when Config.nsnotification_center_checker_backend ->
        L.d_strln
          ( " ERROR: Object " ^ Pvar.to_string pvar
          ^ " is being deallocated while still registered in a notification center" ) ;
        let desc = Localise.desc_registered_observer_being_deallocated pvar loc in
        raise (Exceptions.Registered_observer_being_deallocated (desc, __POS__))
    | _ ->
        () )
  | _ ->
      ()


let check_junk pname tenv prop =
  let leaks_reported = ref [] in
  let remove_junk_once fp_part fav_root sigma =
    let id_considered_reachable =
      (* reachability function *)
      let reach_set = sigma_reachable fav_root sigma in
      fun id -> Ident.Set.mem id reach_set
    in
    let should_remove_hpred entries =
      let predicate = function
        | Exp.Var id ->
            (Ident.is_primed id || Ident.is_footprint id)
            && (not (Ident.Set.mem id fav_root))
            && not (id_considered_reachable id)
        | _ ->
            false
      in
      List.for_all ~f:predicate entries
    in
    let rec remove_junk_recursive sigma_done sigma_todo =
      match sigma_todo with
      | [] ->
          List.rev sigma_done
      | hpred :: sigma_todo' ->
          let entries = Sil.hpred_entries hpred in
          if should_remove_hpred entries then (
            let part = if fp_part then "footprint" else "normal" in
            L.d_strln (".... Prop with garbage in " ^ part ^ " part ....") ;
            L.d_increase_indent 1 ;
            L.d_strln "PROP:" ;
            Prop.d_prop prop ;
            L.d_ln () ;
            L.d_strln "PREDICATE:" ;
            Prop.d_sigma [hpred] ;
            L.d_ln () ;
            let alloc_attribute =
              (* find the alloc attribute of one of the roots of hpred, if it exists *)
              let res = ref None in
              let do_entry e =
                check_observer_is_unsubscribed_deallocation tenv prop e ;
                match Attribute.get_wontleak tenv prop e with
                | Some (Apred ((Awont_leak as a), _)) ->
                    L.d_strln "WONT_LEAK" ;
                    res := Some a
                | _ -> (
                  match Attribute.get_resource tenv prop e with
                  | Some (Apred ((Aresource {ra_kind= Racquire} as a), _)) ->
                      L.d_str "ATTRIBUTE: " ;
                      PredSymb.d_attribute a ;
                      L.d_ln () ;
                      res := Some a
                  | _ -> (
                    match Attribute.get_undef tenv prop e with
                    | Some (Apred ((Aundef _ as a), _)) ->
                        L.d_strln "UNDEF" ;
                        res := Some a
                    | _ ->
                        () ) )
              in
              List.iter ~f:do_entry entries ; !res
            in
            L.d_decrease_indent 1 ;
            let is_undefined =
              Option.value_map ~f:PredSymb.is_undef ~default:false alloc_attribute
            in
            let resource =
              match Errdesc.hpred_is_open_resource tenv prop hpred with
              | Some res ->
                  res
              | None ->
                  PredSymb.Rmemory PredSymb.Mmalloc
            in
            let ml_bucket_opt =
              match resource with
              | (PredSymb.Rmemory PredSymb.Mnew | PredSymb.Rmemory PredSymb.Mnew_array)
                when Language.curr_language_is Clang ->
                  Mleak_buckets.should_raise_cpp_leak
              | _ ->
                  None
            in
            let exn_leak =
              Exceptions.Leak
                ( fp_part
                , hpred
                , Errdesc.explain_leak tenv hpred prop alloc_attribute ml_bucket_opt
                , !Absarray.array_abstraction_performed
                , resource
                , __POS__ )
            in
            let ignore_resource, exn =
              match (alloc_attribute, resource) with
              | Some PredSymb.Awont_leak, Rmemory _ ->
                  (true, exn_leak)
              | Some _, Rmemory Mobjc ->
                  (true, exn_leak)
              | (Some _, Rmemory Mnew | Some _, Rmemory Mnew_array)
                when Language.curr_language_is Clang ->
                  (is_none ml_bucket_opt, exn_leak)
              | Some _, Rmemory _ ->
                  (Language.curr_language_is Java, exn_leak)
              | Some _, Rignore ->
                  (true, exn_leak)
              | Some _, Rfile when Config.tracing ->
                  (true, exn_leak)
              | Some _, Rfile ->
                  (false, exn_leak)
              | Some _, Rlock ->
                  (false, exn_leak)
              | _ ->
                  (Language.curr_language_is Java, exn_leak)
            in
            let already_reported () =
              let attr_opt_equal ao1 ao2 =
                match (ao1, ao2) with
                | None, None ->
                    true
                | Some a1, Some a2 ->
                    PredSymb.equal a1 a2
                | Some _, None | None, Some _ ->
                    false
              in
              (is_none alloc_attribute && !leaks_reported <> [])
              || (* None attribute only reported if it's the first one *)
                 List.mem ~equal:attr_opt_equal !leaks_reported alloc_attribute
            in
            let ignore_leak =
              !Config.allow_leak || ignore_resource || is_undefined || already_reported ()
            in
            let report_and_continue = Language.curr_language_is Java || !Config.footprint in
            let report_leak () =
              if not report_and_continue then raise exn
              else (
                Reporting.log_issue_deprecated_using_state Exceptions.Error pname exn ;
                leaks_reported := alloc_attribute :: !leaks_reported )
            in
            if not ignore_leak then report_leak () ;
            remove_junk_recursive sigma_done sigma_todo' )
          else remove_junk_recursive (hpred :: sigma_done) sigma_todo'
    in
    remove_junk_recursive [] sigma
  in
  let rec remove_junk fp_part fav_root sigma =
    (* call remove_junk_once until sigma stops shrinking *)
    let sigma' = remove_junk_once fp_part fav_root sigma in
    if Int.equal (List.length sigma') (List.length sigma) then sigma'
    else remove_junk fp_part fav_root sigma'
  in
  let sigma_new =
    let fav_sub = Sil.exp_subst_free_vars prop.Prop.sub |> Ident.set_of_sequence in
    let fav_sub_sigmafp =
      Prop.sigma_free_vars prop.Prop.sigma_fp |> Ident.set_of_sequence ~init:fav_sub
    in
    remove_junk false fav_sub_sigmafp prop.Prop.sigma
  in
  let sigma_fp_new = remove_junk true Ident.Set.empty prop.Prop.sigma_fp in
  if Prop.equal_sigma prop.Prop.sigma sigma_new && Prop.equal_sigma prop.Prop.sigma_fp sigma_fp_new
  then prop
  else Prop.normalize tenv (Prop.set prop ~sigma:sigma_new ~sigma_fp:sigma_fp_new)


(** Check whether the prop contains junk.
    If it does, and [Config.allowleak] is true, remove the junk, otherwise raise a Leak exception. *)
let abstract_junk pname tenv prop =
  Absarray.array_abstraction_performed := false ;
  check_junk pname tenv prop


(** Remove redundant elements in an array, and check for junk afterwards *)
let remove_redundant_array_elements pname tenv prop =
  Absarray.array_abstraction_performed := false ;
  let prop' = Absarray.remove_redundant_elements tenv prop in
  check_junk pname tenv prop'


let abstract_prop pname tenv ~(rename_primed : bool) ~(from_abstract_footprint : bool) p =
  Absarray.array_abstraction_performed := false ;
  let pure_abs_p = abstract_pure_part tenv ~from_abstract_footprint:true p in
  let array_abs_p =
    if from_abstract_footprint then pure_abs_p
    else
      abstract_pure_part tenv ~from_abstract_footprint
        (Absarray.abstract_array_check tenv pure_abs_p)
  in
  let abs_p = abs_rules_apply tenv array_abs_p in
  let abs_p = abstract_gc tenv abs_p in
  (* abstraction might enable more gc *)
  let abs_p = check_junk pname tenv abs_p in
  let ren_abs_p =
    if rename_primed then Prop.prop_rename_primed_footprint_vars tenv abs_p else abs_p
  in
  ren_abs_p


let get_local_stack cur_sigma init_sigma =
  let filter_stack = function
    | Sil.Hpointsto (Exp.Lvar _, _, _) ->
        true
    | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ ->
        false
  in
  let get_stack_var = function
    | Sil.Hpointsto (Exp.Lvar pvar, _, _) ->
        pvar
    | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ ->
        assert false
  in
  let filter_local_stack olds = function
    | Sil.Hpointsto (Exp.Lvar pvar, _, _) ->
        not (List.exists ~f:(Pvar.equal pvar) olds)
    | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ ->
        false
  in
  let init_stack = List.filter ~f:filter_stack init_sigma in
  let init_stack_pvars = List.map ~f:get_stack_var init_stack in
  let cur_local_stack = List.filter ~f:(filter_local_stack init_stack_pvars) cur_sigma in
  let cur_local_stack_pvars = List.map ~f:get_stack_var cur_local_stack in
  (cur_local_stack, cur_local_stack_pvars)


(** Extract the footprint, add a local stack and return it as a prop *)
let extract_footprint_for_abs (p : 'a Prop.t) : Prop.exposed Prop.t * Pvar.t list =
  let sigma = p.Prop.sigma in
  let pi_fp = p.Prop.pi_fp in
  let sigma_fp = p.Prop.sigma_fp in
  let local_stack, local_stack_pvars = get_local_stack sigma sigma_fp in
  let p0 = Prop.from_sigma (local_stack @ sigma_fp) in
  let p1 = Prop.set p0 ~pi:pi_fp in
  (p1, local_stack_pvars)


let remove_local_stack sigma pvars =
  let filter_non_stack = function
    | Sil.Hpointsto (Exp.Lvar pvar, _, _) ->
        not (List.exists ~f:(Pvar.equal pvar) pvars)
    | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ ->
        true
  in
  List.filter ~f:filter_non_stack sigma


(** [prop_set_fooprint p p_foot] removes a local stack from [p_foot],
    and sets proposition [p_foot] as footprint of [p]. *)
let set_footprint_for_abs (p : 'a Prop.t) (p_foot : 'a Prop.t) local_stack_pvars :
    Prop.exposed Prop.t =
  let p_foot_pure = Prop.get_pure p_foot in
  let p_sigma_fp = p_foot.Prop.sigma in
  let pi = p_foot_pure in
  let sigma = remove_local_stack p_sigma_fp local_stack_pvars in
  Prop.set p ~pi_fp:pi ~sigma_fp:sigma


(** Abstract the footprint of prop *)
let abstract_footprint pname (tenv : Tenv.t) (prop : Prop.normal Prop.t) : Prop.normal Prop.t =
  let p, added_local_vars = extract_footprint_for_abs prop in
  let p_abs =
    abstract_prop pname tenv ~rename_primed:false ~from_abstract_footprint:true
      (Prop.normalize tenv p)
  in
  let prop' = set_footprint_for_abs prop p_abs added_local_vars in
  Prop.normalize tenv prop'


let abstract_ pname pay tenv p =
  if pay then SymOp.pay () ;
  (* pay one symop *)
  let p' = if !Config.footprint then abstract_footprint pname tenv p else p in
  abstract_prop pname tenv ~rename_primed:true ~from_abstract_footprint:false p'


let abstract pname tenv p = abstract_ pname true tenv p

let abstract_no_symop pname tenv p = abstract_ pname false tenv p

let lifted_abstract pname tenv pset =
  let f p = if Prover.check_inconsistency tenv p then None else Some (abstract pname tenv p) in
  let abstracted_pset = Propset.map_option tenv f pset in
  abstracted_pset

(***************** End of Main Abstraction Functions *****************)