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(*
* Copyright (c) 2009 - 2013 Monoidics ltd.
* Copyright (c) 2013 - present Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*)
open! IStd
(** Re-arrangement and extension of structures with fresh variables *)
module L = Logging
module F = Format
let list_product l1 l2 =
let l1' = List.rev l1 in
let l2' = List.rev l2 in
List.fold
~f:(fun acc x -> List.fold ~f:(fun acc' y -> (x, y) :: acc') ~init:acc l2')
~init:[] l1'
let rec list_rev_and_concat l1 l2 =
match l1 with [] -> l2 | x1 :: l1' -> list_rev_and_concat l1' (x1 :: l2)
(** Check whether the index is out of bounds.
If the length is - 1, no check is performed.
If the index is provably out of bound, a bound error is given.
If the length is a constant and the index is not provably in bound, a warning is given.
*)
let check_bad_index tenv pname p len index loc =
let len_is_constant = match len with Exp.Const _ -> true | _ -> false in
let index_provably_out_of_bound () =
let index_too_large = Prop.mk_inequality tenv (Exp.BinOp (Binop.Le, len, index)) in
let index_negative = Prop.mk_inequality tenv (Exp.BinOp (Binop.Le, index, Exp.minus_one)) in
Prover.check_atom tenv p index_too_large || Prover.check_atom tenv p index_negative
in
let index_provably_in_bound () =
let len_minus_one = Exp.BinOp (Binop.PlusA, len, Exp.minus_one) in
let index_not_too_large =
Prop.mk_inequality tenv (Exp.BinOp (Binop.Le, index, len_minus_one))
in
let index_nonnegative = Prop.mk_inequality tenv (Exp.BinOp (Binop.Le, Exp.zero, index)) in
Prover.check_zero tenv index
|| (* index 0 always in bound, even when we know nothing about len *)
Prover.check_atom tenv p index_not_too_large && Prover.check_atom tenv p index_nonnegative
in
let index_has_bounds () =
match Prover.get_bounds tenv p index with Some _, Some _ -> true | _ -> false
in
let get_const_opt = function Exp.Const Const.Cint n -> Some n | _ -> None in
if not (index_provably_in_bound ()) then
let len_const_opt = get_const_opt len in
let index_const_opt = get_const_opt index in
if index_provably_out_of_bound () then
let deref_str = Localise.deref_str_array_bound len_const_opt index_const_opt in
let exn =
Exceptions.Array_out_of_bounds_l1
(Errdesc.explain_array_access tenv deref_str p loc, __POS__)
in
Reporting.log_warning_deprecated pname exn
else if len_is_constant then
let deref_str = Localise.deref_str_array_bound len_const_opt index_const_opt in
let desc = Errdesc.explain_array_access tenv deref_str p loc in
let exn =
if index_has_bounds () then Exceptions.Array_out_of_bounds_l2 (desc, __POS__)
else Exceptions.Array_out_of_bounds_l3 (desc, __POS__)
in
Reporting.log_warning_deprecated pname exn
(** Perform bounds checking *)
let bounds_check tenv pname prop len e =
if Config.trace_rearrange then (
L.d_str "Bounds check index:" ; Sil.d_exp e ; L.d_str " len: " ; Sil.d_exp len ; L.d_ln () ) ;
check_bad_index tenv pname prop len e
let rec create_struct_values pname tenv orig_prop footprint_part kind max_stamp (t: Typ.t)
(off: Sil.offset list) inst : Sil.atom list * Sil.strexp * Typ.t =
if Config.trace_rearrange then (
L.d_increase_indent 1 ;
L.d_strln "entering create_struct_values" ;
L.d_str "typ: " ;
Typ.d_full t ;
L.d_ln () ;
L.d_str "off: " ;
Sil.d_offset_list off ;
L.d_ln () ;
L.d_ln () ) ;
let new_id () =
incr max_stamp ;
Ident.create kind !max_stamp
in
let res =
let fail t off pos =
L.d_str "create_struct_values type:" ;
Typ.d_full t ;
L.d_str " off: " ;
Sil.d_offset_list off ;
L.d_ln () ;
raise (Exceptions.Bad_footprint pos)
in
match (t.desc, off) with
| Tstruct _, []
-> ([], Sil.Estruct ([], inst), t)
| Tstruct name, (Off_fld (f, _)) :: off' -> (
match Tenv.lookup tenv name with
| Some ({fields; statics} as struct_typ) -> (
match List.find ~f:(fun (f', _, _) -> Typ.Fieldname.equal f f') (fields @ statics) with
| Some (_, t', _)
-> let atoms', se', res_t' =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp t' off' inst
in
let se = Sil.Estruct ([(f, se')], inst) in
let replace_typ_of_f (f', t', a') =
if Typ.Fieldname.equal f f' then (f, res_t', a') else (f', t', a')
in
let fields' =
List.sort ~cmp:Typ.Struct.compare_field (List.map ~f:replace_typ_of_f fields)
in
ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
(atoms', se, t)
| None
-> fail t off __POS__ )
| None
-> fail t off __POS__ )
| Tstruct _, (Off_index e) :: off'
-> let atoms', se', res_t' =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp t off' inst
in
let e' = Sil.array_clean_new_index footprint_part e in
let len = Exp.Var (new_id ()) in
let se = Sil.Earray (len, [(e', se')], inst) in
let res_t = Typ.mk (Tarray (res_t', None, None)) in
(Sil.Aeq (e, e') :: atoms', se, res_t)
| Tarray (t', len_, stride_), off
-> (
let len =
match len_ with None -> Exp.Var (new_id ()) | Some len -> Exp.Const (Const.Cint len)
in
match off with
| []
-> ([], Sil.Earray (len, [], inst), t)
| (Sil.Off_index e) :: off'
-> bounds_check tenv pname orig_prop len e (State.get_loc ()) ;
let atoms', se', res_t' =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp t' off' inst
in
let e' = Sil.array_clean_new_index footprint_part e in
let se = Sil.Earray (len, [(e', se')], inst) in
let res_t = Typ.mk ~default:t (Tarray (res_t', len_, stride_)) in
(Sil.Aeq (e, e') :: atoms', se, res_t)
| (Sil.Off_fld _) :: _
-> assert false )
| Tint _, [] | Tfloat _, [] | Tvoid, [] | Tfun _, [] | Tptr _, [] | TVar _, []
-> let id = new_id () in
([], Sil.Eexp (Exp.Var id, inst), t)
| (Tint _ | Tfloat _ | Tvoid | Tfun _ | Tptr _ | TVar _), (Off_index e) :: off'
-> (* In this case, we lift t to the t array. *)
let t', mk_typ_f =
match t.Typ.desc with
| Typ.Tptr (t', _)
-> (
(t', function desc -> Typ.mk ~default:t desc) )
| _
-> (t, fun desc -> Typ.mk desc)
in
let len = Exp.Var (new_id ()) in
let atoms', se', res_t' =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp t' off' inst
in
let e' = Sil.array_clean_new_index footprint_part e in
let se = Sil.Earray (len, [(e', se')], inst) in
let res_t = mk_typ_f (Tarray (res_t', None, None)) in
(Sil.Aeq (e, e') :: atoms', se, res_t)
| Tint _, _ | Tfloat _, _ | Tvoid, _ | Tfun _, _ | Tptr _, _ | TVar _, _
-> fail t off __POS__
in
( if Config.trace_rearrange then
let _, se, _ = res in
L.d_strln "exiting create_struct_values, returning" ;
Sil.d_sexp se ;
L.d_decrease_indent 1 ;
L.d_ln () ;
L.d_ln () ) ;
res
(** Extend the strexp by populating the path indicated by [off].
This means that it will add missing flds and do the case - analysis
for array accesses. This does not catch the array - bounds errors.
If we want to implement the checks for array bounds errors,
we need to change this function. *)
let rec _strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se (typ: Typ.t)
(off: Sil.offset list) inst =
let new_id () =
incr max_stamp ;
Ident.create kind !max_stamp
in
match (off, se, typ.desc) with
| [], Sil.Eexp _, _ | [], Sil.Estruct _, _
-> [([], se, typ)]
| [], Sil.Earray _, _
-> let off_new = Sil.Off_index Exp.zero :: off in
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se typ off_new inst
| (Off_fld _) :: _, Sil.Earray _, Tarray _
-> let off_new = Sil.Off_index Exp.zero :: off in
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se typ off_new inst
| (Off_fld (f, _)) :: off', Sil.Estruct (fsel, inst'), Tstruct name -> (
match Tenv.lookup tenv name with
| Some ({fields; statics} as struct_typ) -> (
match List.find ~f:(fun (f', _, _) -> Typ.Fieldname.equal f f') (fields @ statics) with
| Some (_, typ', _) -> (
match List.find ~f:(fun (f', _) -> Typ.Fieldname.equal f f') fsel with
| Some (_, se')
-> let atoms_se_typ_list' =
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se' typ'
off' inst
in
let replace acc (res_atoms', res_se', res_typ') =
let replace_fse (f1, _ as ft1) =
if Typ.Fieldname.equal f1 f then (f1, res_se') else ft1
in
let res_fsel' =
List.sort
~cmp:[%compare : Typ.Fieldname.t * Sil.strexp]
(List.map ~f:replace_fse fsel)
in
let replace_fta (f1, _, a1 as fta1) =
if Typ.Fieldname.equal f f1 then (f1, res_typ', a1) else fta1
in
let fields' =
List.sort ~cmp:Typ.Struct.compare_field (List.map ~f:replace_fta fields)
in
ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
(res_atoms', Sil.Estruct (res_fsel', inst'), typ) :: acc
in
List.fold ~f:replace ~init:[] atoms_se_typ_list'
| None
-> let atoms', se', res_typ' =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp typ' off'
inst
in
let res_fsel' =
List.sort ~cmp:[%compare : Typ.Fieldname.t * Sil.strexp] ((f, se') :: fsel)
in
let replace_fta (f', t', a') =
if Typ.Fieldname.equal f' f then (f, res_typ', a') else (f', t', a')
in
let fields' =
List.sort ~cmp:Typ.Struct.compare_field (List.map ~f:replace_fta fields)
in
ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
[(atoms', Sil.Estruct (res_fsel', inst'), typ)] )
| None
-> raise (Exceptions.Missing_fld (f, __POS__)) )
| None
-> raise (Exceptions.Missing_fld (f, __POS__)) )
| (Off_fld _) :: _, _, _
-> raise (Exceptions.Bad_footprint __POS__)
| (Off_index _) :: _, Sil.Eexp _, (Tint _ | Tfloat _ | Tvoid | Tfun _ | Tptr _)
| (Off_index _) :: _, Sil.Estruct _, Tstruct _
-> (* L.d_strln_color Orange "turn into an array"; *)
let len =
match se with
| Sil.Eexp (_, Sil.Ialloc)
-> Exp.one (* if allocated explicitly, we know len is 1 *)
| _
-> if Config.type_size then Exp.one (* Exp.Sizeof (typ, Subtype.exact) *)
else Exp.Var (new_id ())
in
let se_new = Sil.Earray (len, [(Exp.zero, se)], inst) in
let typ_new = Typ.mk (Tarray (typ, None, None)) in
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se_new typ_new off
inst
| (Off_index e) :: off', Sil.Earray (len, esel, inst_arr), Tarray (typ', len_for_typ', stride)
-> (
bounds_check tenv pname orig_prop len e (State.get_loc ()) ;
match List.find ~f:(fun (e', _) -> Exp.equal e e') esel with
| Some (_, se')
-> let atoms_se_typ_list' =
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se' typ' off'
inst
in
let replace acc (res_atoms', res_se', res_typ') =
let replace_ise ise = if Exp.equal e (fst ise) then (e, res_se') else ise in
let res_esel' = List.map ~f:replace_ise esel in
if Typ.equal res_typ' typ' || Int.equal (List.length res_esel') 1 then
( res_atoms'
, Sil.Earray (len, res_esel', inst_arr)
, Typ.mk ~default:typ (Tarray (res_typ', len_for_typ', stride)) ) :: acc
else raise (Exceptions.Bad_footprint __POS__)
in
List.fold ~f:replace ~init:[] atoms_se_typ_list'
| None
-> array_case_analysis_index pname tenv orig_prop footprint_part kind max_stamp len esel
len_for_typ' typ' typ e off' inst_arr inst )
| _, _, _
-> raise (Exceptions.Bad_footprint __POS__)
and array_case_analysis_index pname tenv orig_prop footprint_part kind max_stamp array_len
array_cont typ_array_len typ_cont typ_array index off inst_arr inst =
let check_sound t' =
if not (Typ.equal typ_cont t' || List.is_empty array_cont) then
raise (Exceptions.Bad_footprint __POS__)
in
let index_in_array =
List.exists ~f:(fun (i, _) -> Prover.check_equal tenv Prop.prop_emp index i) array_cont
in
let array_is_full =
match array_len with
| Exp.Const Const.Cint n'
-> IntLit.geq (IntLit.of_int (List.length array_cont)) n'
| _
-> false
in
if index_in_array then
let array_default = Sil.Earray (array_len, array_cont, inst_arr) in
let typ_default = Typ.mk ~default:typ_array (Tarray (typ_cont, typ_array_len, None)) in
[([], array_default, typ_default)]
else if !Config.footprint then
let atoms, elem_se, elem_typ =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp typ_cont off inst
in
check_sound elem_typ ;
let cont_new =
List.sort ~cmp:[%compare : Exp.t * Sil.strexp] ((index, elem_se) :: array_cont)
in
let array_new = Sil.Earray (array_len, cont_new, inst_arr) in
let typ_new = Typ.mk ~default:typ_array (Tarray (elem_typ, typ_array_len, None)) in
[(atoms, array_new, typ_new)]
else
let res_new =
if array_is_full then []
else
let atoms, elem_se, elem_typ =
create_struct_values pname tenv orig_prop footprint_part kind max_stamp typ_cont off inst
in
check_sound elem_typ ;
let cont_new =
List.sort ~cmp:[%compare : Exp.t * Sil.strexp] ((index, elem_se) :: array_cont)
in
let array_new = Sil.Earray (array_len, cont_new, inst_arr) in
let typ_new = Typ.mk ~default:typ_array (Tarray (elem_typ, typ_array_len, None)) in
[(atoms, array_new, typ_new)]
in
let rec handle_case acc isel_seen_rev = function
| []
-> List.concat (List.rev (res_new :: acc))
| (i, se as ise) :: isel_unseen
-> let atoms_se_typ_list =
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se typ_cont
off inst
in
let atoms_se_typ_list' =
List.fold
~f:(fun acc' (atoms', se', typ') ->
check_sound typ' ;
let atoms_new = Sil.Aeq (index, i) :: atoms' in
let isel_new = list_rev_and_concat isel_seen_rev ((i, se') :: isel_unseen) in
let array_new = Sil.Earray (array_len, isel_new, inst_arr) in
let typ_new = Typ.mk ~default:typ_array (Tarray (typ', typ_array_len, None)) in
(atoms_new, array_new, typ_new) :: acc')
~init:[] atoms_se_typ_list
in
let acc_new = atoms_se_typ_list' :: acc in
let isel_seen_rev_new = ise :: isel_seen_rev in
handle_case acc_new isel_seen_rev_new isel_unseen
in
handle_case [] [] array_cont
let exp_has_only_footprint_ids e =
let fav = Sil.exp_fav e in
Sil.fav_filter_ident fav (fun id -> not (Ident.is_footprint id)) ;
Sil.fav_is_empty fav
let laundry_offset_for_footprint max_stamp offs_in =
let rec laundry offs_seen eqs offs =
match offs with
| []
-> (List.rev offs_seen, List.rev eqs)
| (Sil.Off_fld _ as off) :: offs'
-> let offs_seen' = off :: offs_seen in
laundry offs_seen' eqs offs'
| (Sil.Off_index idx as off) :: offs'
-> if exp_has_only_footprint_ids idx then
let offs_seen' = off :: offs_seen in
laundry offs_seen' eqs offs'
else
let () = incr max_stamp in
let fid_new = Ident.create Ident.kfootprint !max_stamp in
let exp_new = Exp.Var fid_new in
let off_new = Sil.Off_index exp_new in
let offs_seen' = off_new :: offs_seen in
let eqs' = (fid_new, idx) :: eqs in
laundry offs_seen' eqs' offs'
in
laundry [] [] offs_in
let strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se te
(off: Sil.offset list) inst =
let typ = Exp.texp_to_typ None te in
let off', laundry_atoms =
let off', eqs = laundry_offset_for_footprint max_stamp off in
(* do laundry_offset whether footprint_part is true or not, so max_stamp is modified anyway *)
if footprint_part then (off', List.map ~f:(fun (id, e) -> Prop.mk_eq tenv (Exp.Var id) e) eqs)
else (off, [])
in
if Config.trace_rearrange then (
L.d_str "entering strexp_extend_values se: " ;
Sil.d_sexp se ;
L.d_str " typ: " ;
Typ.d_full typ ;
L.d_str " off': " ;
Sil.d_offset_list off' ;
L.d_strln (if footprint_part then " FP" else " RE") ) ;
let atoms_se_typ_list =
_strexp_extend_values pname tenv orig_prop footprint_part kind max_stamp se typ off' inst
in
let atoms_se_typ_list_filtered =
let check_neg_atom atom =
Prover.check_atom tenv Prop.prop_emp (Prover.atom_negate tenv atom)
in
let check_not_inconsistent (atoms, _, _) = not (List.exists ~f:check_neg_atom atoms) in
List.filter ~f:check_not_inconsistent atoms_se_typ_list
in
if Config.trace_rearrange then L.d_strln "exiting strexp_extend_values" ;
let sizeof_data =
match te with
| Exp.Sizeof sizeof_data
-> sizeof_data
| _
-> {Exp.typ= Typ.mk Typ.Tvoid; nbytes= None; dynamic_length= None; subtype= Subtype.exact}
in
List.map
~f:(fun (atoms', se', typ') ->
(laundry_atoms @ atoms', se', Exp.Sizeof {sizeof_data with typ= typ'}))
atoms_se_typ_list_filtered
let collect_root_offset exp =
let root = Exp.root_of_lexp exp in
let offsets = Sil.exp_get_offsets exp in
(root, offsets)
(** Exp.Construct a points-to predicate for an expression, to add to a footprint. *)
let mk_ptsto_exp_footprint pname tenv orig_prop (lexp, typ) max_stamp inst
: Sil.hpred * Sil.hpred * Sil.atom list =
let root, off = collect_root_offset lexp in
if not (exp_has_only_footprint_ids root) then
if (* in angelic mode, purposely ignore dangling pointer warnings during the footprint phase -- we
* will fix them during the re - execution phase *)
not (Config.angelic_execution && !Config.footprint)
then (
L.internal_error "!!!! Footprint Error, Bad Root : %a !!!! @\n" Exp.pp lexp ;
let deref_str = Localise.deref_str_dangling None in
let err_desc = Errdesc.explain_dereference tenv deref_str orig_prop (State.get_loc ()) in
raise (Exceptions.Dangling_pointer_dereference (None, err_desc, __POS__)) ) ;
let off_foot, eqs = laundry_offset_for_footprint max_stamp off in
let subtype =
match !Config.curr_language with
| Config.Clang
-> Subtype.exact
| Config.Java
-> Subtype.subtypes
in
let create_ptsto footprint_part off0 =
match (root, off0, typ.Typ.desc) with
| Exp.Lvar pvar, [], Typ.Tfun _
-> let fun_name = Typ.Procname.from_string_c_fun (Mangled.to_string (Pvar.get_name pvar)) in
let fun_exp = Exp.Const (Const.Cfun fun_name) in
( []
, Prop.mk_ptsto tenv root (Sil.Eexp (fun_exp, inst))
(Exp.Sizeof {typ; nbytes= None; dynamic_length= None; subtype}) )
| _, [], Typ.Tfun _
-> let atoms, se, typ =
create_struct_values pname tenv orig_prop footprint_part Ident.kfootprint max_stamp typ
off0 inst
in
( atoms
, Prop.mk_ptsto tenv root se
(Exp.Sizeof {typ; nbytes= None; dynamic_length= None; subtype}) )
| _
-> let atoms, se, typ =
create_struct_values pname tenv orig_prop footprint_part Ident.kfootprint max_stamp typ
off0 inst
in
( atoms
, Prop.mk_ptsto tenv root se
(Exp.Sizeof {typ; nbytes= None; dynamic_length= None; subtype}) )
in
let atoms, ptsto_foot = create_ptsto true off_foot in
let sub = Sil.subst_of_list eqs in
let ptsto = Sil.hpred_sub sub ptsto_foot in
let atoms' = List.map ~f:(fun (id, e) -> Prop.mk_eq tenv (Exp.Var id) e) eqs in
(ptsto, ptsto_foot, atoms @ atoms')
(** Check if the path in exp exists already in the current ptsto predicate.
If it exists, return None. Otherwise, return [Some fld] with [fld] the missing field. *)
let prop_iter_check_fields_ptsto_shallow tenv iter lexp =
let offset = Sil.exp_get_offsets lexp in
let _, se, _ =
match Prop.prop_iter_current tenv iter with
| Sil.Hpointsto (e, se, t), _
-> (e, se, t)
| _
-> assert false
in
let rec check_offset se = function
| []
-> None
| (Sil.Off_fld (fld, _)) :: off' -> (
match se with
| Sil.Estruct (fsel, _) -> (
match List.find ~f:(fun (fld', _) -> Typ.Fieldname.equal fld fld') fsel with
| Some (_, se')
-> check_offset se' off'
| None
-> Some fld )
| _
-> Some fld )
| (Sil.Off_index _) :: _
-> None
in
check_offset se offset
let fav_max_stamp fav =
let max_stamp = ref 0 in
let f id = max_stamp := max !max_stamp (Ident.get_stamp id) in
List.iter ~f (Sil.fav_to_list fav) ;
max_stamp
(** [prop_iter_extend_ptsto iter lexp] extends the current psto
predicate in [iter] with enough fields to follow the path in
[lexp] -- field splitting model. It also materializes all
indices accessed in lexp. *)
let prop_iter_extend_ptsto pname tenv orig_prop iter lexp inst =
if Config.trace_rearrange then (
L.d_str "entering prop_iter_extend_ptsto lexp: " ; Sil.d_exp lexp ; L.d_ln () ) ;
let offset = Sil.exp_get_offsets lexp in
let max_stamp = fav_max_stamp (Prop.prop_iter_fav iter) in
let max_stamp_val = !max_stamp in
let extend_footprint_pred = function
| Sil.Hpointsto (e, se, te)
-> let atoms_se_te_list =
strexp_extend_values pname tenv orig_prop true Ident.kfootprint (ref max_stamp_val) se te
offset inst
in
List.map
~f:(fun (atoms', se', te') -> (atoms', Sil.Hpointsto (e, se', te')))
atoms_se_te_list
| Sil.Hlseg (k, hpara, e1, e2, el) -> (
match hpara.Sil.body with
| (Sil.Hpointsto (e', se', te')) :: body_rest
-> let atoms_se_te_list =
strexp_extend_values pname tenv orig_prop true Ident.kfootprint (ref max_stamp_val) se'
te' offset inst
in
let atoms_body_list =
List.map
~f:(fun (atoms0, se0, te0) -> (atoms0, Sil.Hpointsto (e', se0, te0) :: body_rest))
atoms_se_te_list
in
let atoms_hpara_list =
List.map
~f:(fun (atoms, body') -> (atoms, {hpara with Sil.body= body'}))
atoms_body_list
in
List.map
~f:(fun (atoms, hpara') -> (atoms, Sil.Hlseg (k, hpara', e1, e2, el)))
atoms_hpara_list
| _
-> assert false )
| _
-> assert false
in
let atoms_se_te_to_iter e (atoms, se, te) =
let iter' = List.fold ~f:(Prop.prop_iter_add_atom !Config.footprint) ~init:iter atoms in
Prop.prop_iter_update_current iter' (Sil.Hpointsto (e, se, te))
in
let do_extend e se te =
if Config.trace_rearrange then (
L.d_strln "entering do_extend" ;
L.d_str "e: " ;
Sil.d_exp e ;
L.d_str " se : " ;
Sil.d_sexp se ;
L.d_str " te: " ;
Sil.d_texp_full te ;
L.d_ln () ;
L.d_ln () ) ;
let extend_kind =
match e with
(* Determine whether to extend the footprint part or just the normal part *)
| Exp.Var id
when not (Ident.is_footprint id)
-> Ident.kprimed
| Exp.Lvar pvar when Pvar.is_local pvar
-> Ident.kprimed
| _
-> Ident.kfootprint
in
let iter_list =
let atoms_se_te_list =
strexp_extend_values pname tenv orig_prop false extend_kind max_stamp se te offset inst
in
List.map ~f:(atoms_se_te_to_iter e) atoms_se_te_list
in
let res_iter_list =
if Ident.equal_kind extend_kind Ident.kprimed then iter_list
(* normal part already extended: nothing to do *)
else
(* extend footprint part *)
let atoms_fp_sigma_list =
let footprint_sigma = Prop.prop_iter_get_footprint_sigma iter in
let sigma_pto, sigma_rest =
List.partition_tf
~f:(function
| Sil.Hpointsto (e', _, _)
-> Exp.equal e e'
| Sil.Hlseg (_, _, e1, _, _)
-> Exp.equal e e1
| Sil.Hdllseg (_, _, e_iF, _, _, e_iB, _)
-> Exp.equal e e_iF || Exp.equal e e_iB)
footprint_sigma
in
let atoms_sigma_list =
match sigma_pto with
| [hpred]
-> let atoms_hpred_list = extend_footprint_pred hpred in
List.map ~f:(fun (atoms, hpred') -> (atoms, hpred' :: sigma_rest)) atoms_hpred_list
| _
-> L.d_warning "Cannot extend " ;
Sil.d_exp lexp ;
L.d_strln " in" ;
Prop.d_prop (Prop.prop_iter_to_prop tenv iter) ;
L.d_ln () ;
[([], footprint_sigma)]
in
List.map
~f:(fun (atoms, sigma') -> (atoms, List.stable_sort ~cmp:Sil.compare_hpred sigma'))
atoms_sigma_list
in
let iter_atoms_fp_sigma_list = list_product iter_list atoms_fp_sigma_list in
List.map
~f:(fun (iter, (atoms, fp_sigma)) ->
let iter' =
List.fold ~f:(Prop.prop_iter_add_atom !Config.footprint) ~init:iter atoms
in
Prop.prop_iter_replace_footprint_sigma iter' fp_sigma)
iter_atoms_fp_sigma_list
in
let res_prop_list = List.map ~f:(Prop.prop_iter_to_prop tenv) res_iter_list in
L.d_str "in prop_iter_extend_ptsto lexp: " ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_strln "prop before:" ;
let prop_before = Prop.prop_iter_to_prop tenv iter in
Prop.d_prop prop_before ;
L.d_ln () ;
L.d_ln () ;
L.d_ln () ;
L.d_strln "prop list after:" ;
Propgraph.d_proplist prop_before res_prop_list ;
L.d_ln () ;
L.d_ln () ;
L.d_ln () ;
res_iter_list
in
match Prop.prop_iter_current tenv iter with
| Sil.Hpointsto (e, se, te), _
-> do_extend e se te
| _
-> assert false
(** Add a pointsto for [root(lexp): typ] to the sigma and footprint of a
prop, if it's compatible with the allowed footprint
variables. Then, change it into a iterator. This function ensures
that [root(lexp): typ] is the current hpred of the iterator. typ
is the type of the root of lexp. *)
let prop_iter_add_hpred_footprint_to_prop pname tenv prop (lexp, typ) inst =
let max_stamp = fav_max_stamp (Prop.prop_footprint_fav prop) in
let ptsto, ptsto_foot, atoms =
mk_ptsto_exp_footprint pname tenv prop (lexp, typ) max_stamp inst
in
L.d_strln "++++ Adding footprint frame" ;
Prop.d_prop (Prop.prop_hpred_star Prop.prop_emp ptsto) ;
L.d_ln () ;
L.d_ln () ;
let eprop = Prop.expose prop in
let sigma_fp = ptsto_foot :: eprop.Prop.sigma_fp in
let nsigma_fp = Prop.sigma_normalize_prop tenv Prop.prop_emp sigma_fp in
let prop' = Prop.normalize tenv (Prop.set eprop ~sigma_fp:nsigma_fp) in
let prop_new =
List.fold ~f:(Prop.prop_atom_and tenv ~footprint:!Config.footprint) ~init:prop' atoms
in
let iter =
match Prop.prop_iter_create prop_new with
| None
-> (
let prop_new' = Prop.normalize tenv (Prop.prop_hpred_star prop_new ptsto) in
match Prop.prop_iter_create prop_new' with None -> assert false | Some iter -> iter )
| Some iter
-> Prop.prop_iter_prev_then_insert iter ptsto
in
let offsets_default = Sil.exp_get_offsets lexp in
Prop.prop_iter_set_state iter offsets_default
(** If [lexp] is an access to a field that is annotated with @GuardedBy, add constraints to [prop]
expressing the safety conditions for the access. Complain if these conditions cannot be met. *)
let add_guarded_by_constraints tenv prop lexp pdesc =
let lookup = Tenv.lookup tenv in
let pname = Procdesc.get_proc_name pdesc in
let excluded_guardedby_string str =
(* nothing with a space in it can be a valid Java expression, shouldn't warn *)
let is_invalid_exp_str str = String.contains str ' ' in
(* don't warn on @GuardedBy("ui_thread") in any form *)
let is_ui_thread str =
let lowercase_str = String.lowercase str in
String.equal lowercase_str "ui_thread" || String.equal lowercase_str "ui-thread"
|| String.equal lowercase_str "uithread"
in
is_invalid_exp_str str || is_ui_thread str
in
let guarded_by_str_is_this guarded_by_str = String.is_suffix ~suffix:"this" guarded_by_str in
let guarded_by_str_is_class guarded_by_str class_str =
let dollar_normalize s = String.map s ~f:(function '$' -> '.' | c -> c) in
String.is_suffix ~suffix:(dollar_normalize guarded_by_str)
(dollar_normalize (class_str ^ ".class"))
in
let guarded_by_str_is_current_class guarded_by_str = function
| Typ.Procname.Java java_pname
-> (* programmers write @GuardedBy("MyClass.class") when the field is guarded by the class *)
guarded_by_str_is_class guarded_by_str (Typ.Procname.java_get_class_name java_pname)
| _
-> false
in
let guarded_by_str_is_class_this class_name guarded_by_str =
let fully_qualified_this = Printf.sprintf "%s.this" class_name in
String.is_suffix ~suffix:guarded_by_str fully_qualified_this
in
(* return true if [guarded_by_str] is a suffix of "<name_of_super_class>.this" *)
let guarded_by_str_is_super_class_this guarded_by_str pname =
match pname with
| Typ.Procname.Java java_pname
-> let current_class_type_name = Typ.Procname.java_get_class_type_name java_pname in
let comparison class_type_name _ =
guarded_by_str_is_class_this (Typ.Name.to_string class_type_name) guarded_by_str
in
PatternMatch.supertype_exists tenv comparison current_class_type_name
| _
-> false
in
(* return true if [guarded_by_str] is as suffix of "<name_of_current_class>.this" *)
let guarded_by_str_is_current_class_this guarded_by_str = function
| Typ.Procname.Java java_pname
-> guarded_by_str_is_class_this (Typ.Procname.java_get_class_name java_pname) guarded_by_str
| _
-> false
in
let extract_guarded_by_str item_annot =
let annot_extract_guarded_by_str ((annot: Annot.t), _) =
if Annotations.annot_ends_with annot Annotations.guarded_by then
match annot.parameters with
| [guarded_by_str] when not (excluded_guardedby_string guarded_by_str)
-> Some guarded_by_str
| _
-> None
else None
in
List.find_map ~f:annot_extract_guarded_by_str item_annot
in
let extract_suppress_warnings_str item_annot =
let annot_suppress_warnings_str ((annot: Annot.t), _) =
if Annotations.annot_ends_with annot Annotations.suppress_lint then
match annot.parameters with [suppr_str] -> Some suppr_str | _ -> None
else None
in
List.find_map ~f:annot_suppress_warnings_str item_annot
in
(* if [fld] is annotated with @GuardedBy("mLock"), return mLock *)
let get_guarded_by_fld_str fld typ =
match Typ.Struct.get_field_type_and_annotation ~lookup fld typ with
| Some (_, item_annot) -> (
match extract_guarded_by_str item_annot with
| Some "this"
-> (* expand "this" into <classname>.this *)
Some (Printf.sprintf "%s.this" (Typ.Fieldname.java_get_class fld))
| guarded_by_str_opt
-> guarded_by_str_opt )
| _
-> None
in
(* find A.guarded_by_fld_str |-> B and return Some B, or None if there is no such hpred *)
let find_guarded_by_exp guarded_by_str0 sigma =
let is_guarded_by_fld guarded_by_str fld _ =
(* this comparison needs to be somewhat fuzzy, since programmers are free to write
@GuardedBy("mLock"), @GuardedBy("MyClass.mLock"), or use other conventions *)
String.equal (Typ.Fieldname.to_flat_string fld) guarded_by_str
|| String.equal (Typ.Fieldname.to_string fld) guarded_by_str
in
let get_fld_strexp_and_typ typ f flds =
let match_one (fld, strexp) =
match Typ.Struct.get_field_type_and_annotation ~lookup fld typ with
| Some (fld_typ, _) when f fld fld_typ
-> Some (strexp, fld_typ)
| _
-> None
in
List.find_map ~f:match_one flds
in
(* sometimes, programmers will write @GuardedBy("T.f") with the meaning "guarded by the field f
of the object of type T in the current state." note that this is ambiguous when there are
multiple objects of type T, but let's try to respect the intention *)
let match_on_field_type typ flds =
match String.rsplit2 guarded_by_str0 ~on:'.' with
| Some (class_part, field_part)
-> (
let typ_matches_guarded_by _ {Typ.desc} =
match desc with
| Typ.Tptr (ptr_typ, _)
-> String.is_suffix ~suffix:class_part (Typ.to_string ptr_typ)
| _
-> false
in
match get_fld_strexp_and_typ typ typ_matches_guarded_by flds with
| Some (Sil.Eexp (matching_exp, _), _)
-> List.find_map
~f:(function
| Sil.Hpointsto (lhs_exp, Estruct (matching_flds, _), Sizeof {typ= fld_typ})
when Exp.equal lhs_exp matching_exp
-> get_fld_strexp_and_typ fld_typ (is_guarded_by_fld field_part) matching_flds
| _
-> None)
sigma
| _
-> None )
| _
-> None
in
List.find_map
~f:(fun hpred ->
match[@warning "-57"] (* FIXME: silenced warning may be legit *) hpred with
| Sil.Hpointsto ((Const Cclass clazz as lhs_exp), _, Exp.Sizeof {typ})
| Sil.Hpointsto (_, Sil.Eexp ((Const Cclass clazz as lhs_exp), _), Exp.Sizeof {typ})
when guarded_by_str_is_class guarded_by_str0 (Ident.name_to_string clazz)
-> Some (Sil.Eexp (lhs_exp, Sil.inst_none), typ)
| Sil.Hpointsto (_, Estruct (flds, _), Exp.Sizeof {typ}) -> (
match
(* first, try to find a field that exactly matches the guarded-by string *)
get_fld_strexp_and_typ typ (is_guarded_by_fld guarded_by_str0) flds
with
| None when guarded_by_str_is_this guarded_by_str0
-> (* if the guarded-by string is "OuterClass.this", look for "this$n" for some n.
note that this is a bit sketchy when there are mutliple this$n's, but there's
nothing we can do to disambiguate them. *)
get_fld_strexp_and_typ typ (fun f _ -> Typ.Fieldname.java_is_outer_instance f) flds
| None
-> (* can't find an exact match. try a different convention. *)
match_on_field_type typ flds
| Some _ as res_opt
-> res_opt )
| Sil.Hpointsto (Lvar pvar, rhs_exp, Exp.Sizeof {typ})
when ( guarded_by_str_is_current_class_this guarded_by_str0 pname
|| guarded_by_str_is_super_class_this guarded_by_str0 pname )
&& Pvar.is_this pvar
-> Some (rhs_exp, typ)
| _
-> None)
sigma
in
(* warn if the access to [lexp] is not protected by the [guarded_by_fld_str] lock *)
let enforce_guarded_access_ accessed_fld guarded_by_str prop =
(* return true if [pdesc] has an annotation that matches [guarded_by_str] *)
let proc_has_matching_annot pdesc guarded_by_str =
match extract_guarded_by_str (Annotations.pdesc_get_return_annot pdesc) with
| Some proc_guarded_by_str
-> (* the lock is not held, but the procedure is annotated with @GuardedBy *)
String.equal proc_guarded_by_str guarded_by_str
| None
-> false
in
let is_synchronized_on_class guarded_by_str =
guarded_by_str_is_current_class guarded_by_str pname && Procdesc.is_java_synchronized pdesc
&& Typ.Procname.java_is_static pname
in
let warn accessed_fld guarded_by_str =
let loc = State.get_loc () in
let err_desc = Localise.desc_unsafe_guarded_by_access accessed_fld guarded_by_str loc in
let exn = Exceptions.Unsafe_guarded_by_access (err_desc, __POS__) in
Reporting.log_error_deprecated pname exn
in
let rec is_read_write_lock typ =
let str_is_read_write_lock str =
String.is_suffix ~suffix:"ReadWriteUpdateLock" str
|| String.is_suffix ~suffix:"ReadWriteLock" str
in
match typ.Typ.desc with
| Typ.Tstruct name
-> str_is_read_write_lock (Typ.Name.name name)
| Typ.Tptr (typ, _)
-> is_read_write_lock typ
| _
-> false
in
let has_lock guarded_by_exp =
( guarded_by_str_is_current_class_this guarded_by_str pname
|| guarded_by_str_is_super_class_this guarded_by_str pname )
&& Procdesc.is_java_synchronized pdesc
|| guarded_by_str_is_current_class guarded_by_str pname
&& Procdesc.is_java_synchronized pdesc && Typ.Procname.java_is_static pname
|| (* or the prop says we already have the lock *)
List.exists
~f:(function Sil.Apred (Alocked, _) -> true | _ -> false)
(Attribute.get_for_exp tenv prop guarded_by_exp)
in
let guardedby_is_self_referential =
String.equal "itself" (String.lowercase guarded_by_str)
|| String.is_suffix ~suffix:guarded_by_str (Typ.Fieldname.to_string accessed_fld)
in
let proc_has_suppress_guarded_by_annot pdesc =
match extract_suppress_warnings_str (Annotations.pdesc_get_return_annot pdesc) with
| Some suppression_str
-> String.equal suppression_str "InvalidAccessToGuardedField"
| None
-> false
in
let should_warn pdesc =
(* adding this check implements "by reference" semantics for guarded-by rather than "by value"
semantics. if this access is through a local L or field V.f
(where f is not the @GuardedBy field!), we will not warn.
*)
let is_accessible_through_local_ref exp =
List.exists
~f:(function
| Sil.Hpointsto (Lvar _, Eexp (rhs_exp, _), _)
-> Exp.equal exp rhs_exp
| Sil.Hpointsto (_, Estruct (flds, _), _)
-> List.exists
~f:(fun (fld, strexp) ->
match strexp with
| Sil.Eexp (rhs_exp, _)
-> Exp.equal exp rhs_exp && not (Typ.Fieldname.equal fld accessed_fld)
| _
-> false)
flds
| _
-> false)
prop.Prop.sigma
in
Procdesc.get_access pdesc <> PredSymb.Private
&& not (Annotations.pdesc_return_annot_ends_with pdesc Annotations.visibleForTesting)
&& not (Typ.Procname.java_is_access_method (Procdesc.get_proc_name pdesc))
&& not (is_accessible_through_local_ref lexp) && not guardedby_is_self_referential
&& not (proc_has_suppress_guarded_by_annot pdesc)
in
match find_guarded_by_exp guarded_by_str prop.Prop.sigma with
| Some (Sil.Eexp (guarded_by_exp, _), typ)
-> if is_read_write_lock typ then
(* TODO: model/understand read-write locks rather than ignoring them *)
prop
else if has_lock guarded_by_exp then
(* we have the lock; no need to add a proof obligation *)
(* TODO: materialize [fld], but don't add [fld] to the footprint. *)
prop
else if (* we don't know if we have the lock or not. *)
should_warn pdesc then (
(* non-private method; can't ensure that the lock is held. warn. *)
warn accessed_fld guarded_by_str ;
prop )
else
(* private method. add locked proof obligation to [pdesc] *)
Attribute.add tenv ~footprint:true prop Alocked [guarded_by_exp]
| _
-> if not
( proc_has_matching_annot pdesc guarded_by_str
|| is_synchronized_on_class guarded_by_str )
&& should_warn pdesc
then
(* can't find the object the annotation refers to, and procedure is not annotated. warn *)
warn accessed_fld guarded_by_str
else
(* procedure has same GuardedBy annotation as the field. we would like to add a proof
obligation, but we can't (because we can't find an expression corresponding to the
lock in the current prop). so just be silent. *)
() ;
prop
in
let enforce_guarded_access fld typ prop =
match get_guarded_by_fld_str fld typ with
| Some guarded_by_fld_str
-> enforce_guarded_access_ fld guarded_by_fld_str prop
| None
-> prop
in
let check_fld_locks typ prop_acc (fld, strexp) =
match strexp with
| Sil.Eexp (exp, _) when Exp.equal exp lexp
-> enforce_guarded_access fld typ prop_acc
| _
-> prop_acc
in
let hpred_check_flds prop_acc = function
| Sil.Hpointsto (_, Estruct (flds, _), Sizeof {typ})
-> List.fold ~f:(check_fld_locks typ) ~init:prop_acc flds
| _
-> prop_acc
in
match lexp with
| Exp.Lfield (_, fld, typ)
-> (* check for direct access to field annotated with @GuardedBy *)
enforce_guarded_access fld typ prop
| _
-> (* check for access via alias *)
List.fold ~f:hpred_check_flds ~init:prop prop.Prop.sigma
(** Add a pointsto for [root(lexp): typ] to the iterator and to the
footprint, if it's compatible with the allowed footprint
variables. This function ensures that [root(lexp): typ] is the
current hpred of the iterator. typ is the type of the root of lexp. *)
let prop_iter_add_hpred_footprint pname tenv orig_prop iter (lexp, typ) inst =
if Config.trace_rearrange then (
L.d_strln "entering prop_iter_add_hpred_footprint" ;
L.d_str "lexp: " ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_str "typ:" ;
Typ.d_full typ ;
L.d_ln () ) ;
let max_stamp = fav_max_stamp (Prop.prop_iter_footprint_fav iter) in
let ptsto, ptsto_foot, atoms =
mk_ptsto_exp_footprint pname tenv orig_prop (lexp, typ) max_stamp inst
in
L.d_strln "++++ Adding footprint frame" ;
Prop.d_prop (Prop.prop_hpred_star Prop.prop_emp ptsto) ;
L.d_ln () ;
L.d_ln () ;
let sigma_fp = ptsto_foot :: Prop.prop_iter_get_footprint_sigma iter in
let iter_foot = Prop.prop_iter_prev_then_insert iter ptsto in
let iter_foot_atoms =
List.fold ~f:(Prop.prop_iter_add_atom !Config.footprint) ~init:iter_foot atoms
in
let iter' = Prop.prop_iter_replace_footprint_sigma iter_foot_atoms sigma_fp in
let offsets_default = Sil.exp_get_offsets lexp in
Prop.prop_iter_set_state iter' offsets_default
exception ARRAY_ACCESS
let rearrange_arith tenv lexp prop =
if Config.trace_rearrange then (
L.d_strln "entering rearrange_arith" ;
L.d_str "lexp: " ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_str "prop: " ;
L.d_ln () ;
Prop.d_prop prop ;
L.d_ln () ;
L.d_ln () ) ;
if Config.array_level >= 2 then raise ARRAY_ACCESS
else
let root = Exp.root_of_lexp lexp in
if Prover.check_allocatedness tenv prop root then raise ARRAY_ACCESS
else raise (Exceptions.Symexec_memory_error __POS__)
let pp_rearrangement_error message prop lexp =
L.d_strln (".... Rearrangement Error .... " ^ message) ;
L.d_str "Exp:" ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_str "Prop:" ;
L.d_ln () ;
Prop.d_prop prop ;
L.d_ln () ;
L.d_ln ()
(** do re-arrangment for an iter whose current element is a pointsto *)
let iter_rearrange_ptsto pname tenv orig_prop iter lexp inst =
if Config.trace_rearrange then (
L.d_increase_indent 1 ;
L.d_strln "entering iter_rearrange_ptsto" ;
L.d_str "lexp: " ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_strln "prop:" ;
Prop.d_prop orig_prop ;
L.d_ln () ;
L.d_strln "iter:" ;
Prop.d_prop (Prop.prop_iter_to_prop tenv iter) ;
L.d_ln () ;
L.d_ln () ) ;
let check_field_splitting () =
match prop_iter_check_fields_ptsto_shallow tenv iter lexp with
| None
-> ()
| Some fld
-> pp_rearrangement_error "field splitting check failed" orig_prop lexp ;
raise (Exceptions.Missing_fld (fld, __POS__))
in
let res =
if !Config.footprint then prop_iter_extend_ptsto pname tenv orig_prop iter lexp inst
else (
check_field_splitting () ;
match Prop.prop_iter_current tenv iter with
| Sil.Hpointsto (e, se, te), offset
-> let max_stamp = fav_max_stamp (Prop.prop_iter_fav iter) in
let atoms_se_te_list =
strexp_extend_values pname tenv orig_prop false Ident.kprimed max_stamp se te offset
inst
in
let handle_case (atoms', se', te') =
let iter' =
List.fold ~f:(Prop.prop_iter_add_atom !Config.footprint) ~init:iter atoms'
in
Prop.prop_iter_update_current iter' (Sil.Hpointsto (e, se', te'))
in
let filter it =
let p = Prop.prop_iter_to_prop tenv it in
not (Prover.check_inconsistency tenv p)
in
List.filter ~f:filter (List.map ~f:handle_case atoms_se_te_list)
| _
-> [iter] )
in
if Config.trace_rearrange then (
L.d_strln "exiting iter_rearrange_ptsto, returning results" ;
Prop.d_proplist_with_typ (List.map ~f:(Prop.prop_iter_to_prop tenv) res) ;
L.d_decrease_indent 1 ;
L.d_ln () ;
L.d_ln () ) ;
res
(** do re-arrangment for an iter whose current element is a nonempty listseg *)
let iter_rearrange_ne_lseg tenv recurse_on_iters iter para e1 e2 elist =
if Config.nelseg then
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_inst1 = Sil.hpara_instantiate para e1 n' elist in
let hpred_list1 = para_inst1 @ [Prop.mk_lseg tenv Sil.Lseg_NE para n' e2 elist] in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_base_case =
let _, para_inst = Sil.hpara_instantiate para e1 e2 elist in
Prop.prop_iter_update_current_by_list iter para_inst
in
recurse_on_iters [iter_inductive_case; iter_base_case]
else
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_inst1 = Sil.hpara_instantiate para e1 n' elist in
let hpred_list1 = para_inst1 @ [Prop.mk_lseg tenv Sil.Lseg_PE para n' e2 elist] in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
recurse_on_iters [iter_inductive_case]
(** do re-arrangment for an iter whose current element is a nonempty dllseg to be unrolled from lhs *)
let iter_rearrange_ne_dllseg_first tenv recurse_on_iters iter para_dll e1 e2 e3 e4 elist =
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_dll_inst1 = Sil.hpara_dll_instantiate para_dll e1 e2 n' elist in
let hpred_list1 =
para_dll_inst1 @ [Prop.mk_dllseg tenv Sil.Lseg_NE para_dll n' e1 e3 e4 elist]
in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_base_case =
let _, para_dll_inst = Sil.hpara_dll_instantiate para_dll e1 e2 e3 elist in
let iter' = Prop.prop_iter_update_current_by_list iter para_dll_inst in
let prop' = Prop.prop_iter_to_prop tenv iter' in
let prop'' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e1 e4 prop' in
match Prop.prop_iter_create prop'' with None -> assert false | Some iter' -> iter'
in
recurse_on_iters [iter_inductive_case; iter_base_case]
(** do re-arrangment for an iter whose current element is a nonempty dllseg to be unrolled from rhs *)
let iter_rearrange_ne_dllseg_last tenv recurse_on_iters iter para_dll e1 e2 e3 e4 elist =
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_dll_inst1 = Sil.hpara_dll_instantiate para_dll e4 n' e3 elist in
let hpred_list1 =
para_dll_inst1 @ [Prop.mk_dllseg tenv Sil.Lseg_NE para_dll e1 e2 e4 n' elist]
in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_base_case =
let _, para_dll_inst = Sil.hpara_dll_instantiate para_dll e4 e2 e3 elist in
let iter' = Prop.prop_iter_update_current_by_list iter para_dll_inst in
let prop' = Prop.prop_iter_to_prop tenv iter' in
let prop'' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e1 e4 prop' in
match Prop.prop_iter_create prop'' with None -> assert false | Some iter' -> iter'
in
recurse_on_iters [iter_inductive_case; iter_base_case]
(** do re-arrangment for an iter whose current element is a possibly empty listseg *)
let iter_rearrange_pe_lseg tenv recurse_on_iters default_case_iter iter para e1 e2 elist =
let iter_nonemp_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_inst1 = Sil.hpara_instantiate para e1 n' elist in
let hpred_list1 = para_inst1 @ [Prop.mk_lseg tenv Sil.Lseg_PE para n' e2 elist] in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_subcases =
let removed_prop = Prop.prop_iter_remove_curr_then_to_prop tenv iter in
let prop' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e1 e2 removed_prop in
match Prop.prop_iter_create prop' with
| None
-> let iter' = default_case_iter (Prop.prop_iter_set_state iter ()) in
[Prop.prop_iter_set_state iter' ()]
| Some iter'
-> [iter_nonemp_case; iter']
in
recurse_on_iters iter_subcases
(** do re-arrangment for an iter whose current element is a possibly empty dllseg to be unrolled from lhs *)
let iter_rearrange_pe_dllseg_first tenv recurse_on_iters default_case_iter iter para_dll e1 e2 e3
e4 elist =
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_dll_inst1 = Sil.hpara_dll_instantiate para_dll e1 e2 n' elist in
let hpred_list1 =
para_dll_inst1 @ [Prop.mk_dllseg tenv Sil.Lseg_PE para_dll n' e1 e3 e4 elist]
in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_subcases =
let removed_prop = Prop.prop_iter_remove_curr_then_to_prop tenv iter in
let prop' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e1 e3 removed_prop in
let prop'' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e2 e4 prop' in
match Prop.prop_iter_create prop'' with
| None
-> let iter' = default_case_iter (Prop.prop_iter_set_state iter ()) in
[Prop.prop_iter_set_state iter' ()]
| Some iter'
-> [iter_inductive_case; iter']
in
recurse_on_iters iter_subcases
(** do re-arrangment for an iter whose current element is a possibly empty dllseg to be unrolled from rhs *)
let iter_rearrange_pe_dllseg_last tenv recurse_on_iters default_case_iter iter para_dll e1 e2 e3 e4
elist =
let iter_inductive_case =
let n' = Exp.Var (Ident.create_fresh Ident.kprimed) in
let _, para_dll_inst1 = Sil.hpara_dll_instantiate para_dll e4 n' e3 elist in
let hpred_list1 =
para_dll_inst1 @ [Prop.mk_dllseg tenv Sil.Lseg_PE para_dll e1 e2 e4 n' elist]
in
Prop.prop_iter_update_current_by_list iter hpred_list1
in
let iter_subcases =
let removed_prop = Prop.prop_iter_remove_curr_then_to_prop tenv iter in
let prop' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e1 e3 removed_prop in
let prop'' = Prop.conjoin_eq tenv ~footprint:!Config.footprint e2 e4 prop' in
match Prop.prop_iter_create prop'' with
| None
-> let iter' = default_case_iter (Prop.prop_iter_set_state iter ()) in
[Prop.prop_iter_set_state iter' ()]
| Some iter'
-> [iter_inductive_case; iter']
in
recurse_on_iters iter_subcases
(** find the type at the offset from the given type expression, if any *)
let type_at_offset tenv texp off =
let rec strip_offset (off: Sil.offset list) (typ: Typ.t) =
match (off, typ.desc) with
| [], _
-> Some typ
| (Off_fld (f, _)) :: off', Tstruct name -> (
match Tenv.lookup tenv name with
| Some {fields} -> (
match List.find ~f:(fun (f', _, _) -> Typ.Fieldname.equal f f') fields with
| Some (_, typ', _)
-> strip_offset off' typ'
| None
-> None )
| None
-> None )
| (Off_index _) :: off', Tarray (typ', _, _)
-> strip_offset off' typ'
| _
-> None
in
match texp with Exp.Sizeof {typ} -> strip_offset off typ | _ -> None
(** Check that the size of a type coming from an instruction does not exceed the size of the type from the pointsto predicate
For example, that a pointer to int is not used to assign to a char *)
let check_type_size tenv pname prop texp off typ_from_instr =
L.d_strln_color Orange "check_type_size" ;
L.d_str "off: " ;
Sil.d_offset_list off ;
L.d_ln () ;
L.d_str "typ_from_instr: " ;
Typ.d_full typ_from_instr ;
L.d_ln () ;
match type_at_offset tenv texp off with
| Some typ_of_object
-> L.d_str "typ_o: " ;
Typ.d_full typ_of_object ;
L.d_ln () ;
if Prover.type_size_comparable typ_from_instr typ_of_object
&& not (Prover.check_type_size_leq typ_from_instr typ_of_object)
then
let deref_str = Localise.deref_str_pointer_size_mismatch typ_from_instr typ_of_object in
let loc = State.get_loc () in
let exn =
Exceptions.Pointer_size_mismatch
(Errdesc.explain_dereference tenv deref_str prop loc, __POS__)
in
Reporting.log_warning_deprecated pname exn
| None
-> L.d_str "texp: " ; Sil.d_texp_full texp ; L.d_ln ()
(** Exposes lexp |->- from iter. In case that it is not possible to
* expose lexp |->-, this function prints an error message and
* faults. There are four things to note. First, typ is the type of the
* root of lexp. Second, prop should mean the same as iter. Third, the
* result [] means that the given input iter is inconsistent. This
* happens when the theorem prover can prove the inconsistency of prop,
* only after unrolling some predicates in prop. This function ensures
* that the theorem prover cannot prove the inconsistency of any of the
* new iters in the result. *)
let rec iter_rearrange pname tenv lexp typ_from_instr prop iter inst
: Sil.offset list Prop.prop_iter list =
let rec root_typ_of_offsets = function
| (Sil.Off_fld (f, fld_typ)) :: _ -> (
match fld_typ.desc with
| Tstruct _
-> (* access through field: get the struct type from the field *)
if Config.trace_rearrange then (
L.d_increase_indent 1 ;
L.d_str "iter_rearrange: root of lexp accesses field " ;
L.d_strln (Typ.Fieldname.to_string f) ;
L.d_str " struct type from field: " ;
Typ.d_full fld_typ ;
L.d_ln () ;
L.d_decrease_indent 1 ;
L.d_ln () ) ;
fld_typ
| _
-> typ_from_instr )
| (Sil.Off_index _) :: off
-> Typ.mk (Tarray (root_typ_of_offsets off, None, None))
| _
-> typ_from_instr
in
let typ = root_typ_of_offsets (Sil.exp_get_offsets lexp) in
if Config.trace_rearrange then (
L.d_increase_indent 1 ;
L.d_strln "entering iter_rearrange" ;
L.d_str "lexp: " ;
Sil.d_exp lexp ;
L.d_ln () ;
L.d_str "typ: " ;
Typ.d_full typ ;
L.d_ln () ;
L.d_str "type from instruction: " ;
Typ.d_full typ_from_instr ;
L.d_ln () ;
L.d_strln "prop:" ;
Prop.d_prop prop ;
L.d_ln () ;
L.d_strln "iter:" ;
Prop.d_prop (Prop.prop_iter_to_prop tenv iter) ;
L.d_ln () ;
L.d_ln () ) ;
let default_case_iter (iter': unit Prop.prop_iter) =
if Config.trace_rearrange then L.d_strln "entering default_case_iter" ;
if !Config.footprint then prop_iter_add_hpred_footprint pname tenv prop iter' (lexp, typ) inst
else if Config.array_level >= 1 && not !Config.footprint && Exp.pointer_arith lexp then
rearrange_arith tenv lexp prop
else (
pp_rearrangement_error "cannot find predicate with root" prop lexp ;
if not !Config.footprint then Printer.force_delayed_prints () ;
raise (Exceptions.Symexec_memory_error __POS__) )
in
let recurse_on_iters iters =
let f_one_iter iter' =
let prop' = Prop.prop_iter_to_prop tenv iter' in
if Prover.check_inconsistency tenv prop' then []
else
iter_rearrange pname tenv (Prop.lexp_normalize_prop tenv prop' lexp) typ prop' iter' inst
in
let rec f_many_iters iters_lst = function
| []
-> List.concat (List.rev iters_lst)
| iter' :: iters'
-> let iters_res' = f_one_iter iter' in
f_many_iters (iters_res' :: iters_lst) iters'
in
f_many_iters [] iters
in
let filter = function
| Sil.Hpointsto (base, _, _) | Sil.Hlseg (_, _, base, _, _)
-> Prover.is_root tenv prop base lexp
| Sil.Hdllseg (_, _, first, _, _, last, _)
-> let result_first = Prover.is_root tenv prop first lexp in
match result_first with
| None
-> Prover.is_root tenv prop last lexp
| Some _
-> result_first
in
let res =
match Prop.prop_iter_find iter filter with
| None
-> [default_case_iter iter]
| Some iter ->
match Prop.prop_iter_current tenv iter with
| Sil.Hpointsto (_, _, texp), off
-> if Config.type_size then check_type_size tenv pname prop texp off typ_from_instr ;
iter_rearrange_ptsto pname tenv prop iter lexp inst
| Sil.Hlseg (Sil.Lseg_NE, para, e1, e2, elist), _
-> iter_rearrange_ne_lseg tenv recurse_on_iters iter para e1 e2 elist
| Sil.Hlseg (Sil.Lseg_PE, para, e1, e2, elist), _
-> iter_rearrange_pe_lseg tenv recurse_on_iters default_case_iter iter para e1 e2 elist
| Sil.Hdllseg (Sil.Lseg_NE, para_dll, e1, e2, e3, e4, elist), _ -> (
match (Prover.is_root tenv prop e1 lexp, Prover.is_root tenv prop e4 lexp) with
| None, None
-> assert false
| Some _, _
-> iter_rearrange_ne_dllseg_first tenv recurse_on_iters iter para_dll e1 e2 e3 e4 elist
| _, Some _
-> iter_rearrange_ne_dllseg_last tenv recurse_on_iters iter para_dll e1 e2 e3 e4 elist )
| Sil.Hdllseg (Sil.Lseg_PE, para_dll, e1, e2, e3, e4, elist), _ ->
match (Prover.is_root tenv prop e1 lexp, Prover.is_root tenv prop e4 lexp) with
| None, None
-> assert false
| Some _, _
-> iter_rearrange_pe_dllseg_first tenv recurse_on_iters default_case_iter iter para_dll e1
e2 e3 e4 elist
| _, Some _
-> iter_rearrange_pe_dllseg_last tenv recurse_on_iters default_case_iter iter para_dll e1
e2 e3 e4 elist
in
if Config.trace_rearrange then (
L.d_strln "exiting iter_rearrange, returning results" ;
Prop.d_proplist_with_typ (List.map ~f:(Prop.prop_iter_to_prop tenv) res) ;
L.d_decrease_indent 1 ;
L.d_ln () ;
L.d_ln () ) ;
res
let is_weak_captured_var pdesc var_name =
let pname = Procdesc.get_proc_name pdesc in
match pname with
| Block _
-> let is_weak_captured (var, typ) =
match typ.Typ.desc with
| Typ.Tptr (_, Pk_objc_weak)
-> String.equal var_name (Mangled.to_string var)
| _
-> false
in
List.exists ~f:is_weak_captured (Procdesc.get_captured pdesc)
| _
-> false
let var_has_annotation ?(check_weak_captured_var= false) pdesc is_annotation pvar =
let is_weak_captured_var = is_weak_captured_var pdesc (Pvar.to_string pvar) in
let ann_sig = Models.get_modelled_annotated_signature (Specs.pdesc_resolve_attributes pdesc) in
AnnotatedSignature.param_has_annot is_annotation pvar ann_sig
|| check_weak_captured_var && is_weak_captured_var
let attr_has_annot is_annotation tenv prop exp =
let attr_has_annot = function
| Sil.Apred ((Aretval (pname, ret_attr) | Aundef (pname, ret_attr, _, _)), _)
when is_annotation ret_attr
-> Some (Typ.Procname.to_string pname)
| _
-> None
in
try List.find_map ~f:attr_has_annot (Attribute.get_for_exp tenv prop exp)
with Not_found -> None
let is_strexp_pt_fld_with_annot tenv obj_str is_annotation typ deref_exp (fld, strexp) =
let lookup = Tenv.lookup tenv in
let fld_has_annot fld =
match Typ.Struct.get_field_type_and_annotation ~lookup fld typ with
| Some (_, annot)
-> is_annotation annot
| _
-> false
in
match strexp with
| Sil.Eexp ((Exp.Var _ as exp), _) when Exp.equal exp deref_exp
-> let has_annot = fld_has_annot fld in
if has_annot then obj_str := Some (Typ.Fieldname.to_simplified_string fld) ;
has_annot
| _
-> true
(* This returns true if the exp is pointed to only by fields or parameters with a given
annotation. In that case it also returns a string representation of the annotation
recipient. *)
let is_only_pt_by_fld_or_param_with_annot ?(check_weak_captured_var= false) pdesc tenv prop
deref_exp is_annotation =
let obj_str = ref None in
let is_pt_by_fld_or_param_with_annot hpred =
match hpred with
| Sil.Hpointsto (Exp.Lvar pvar, Sil.Eexp ((Exp.Var _ as exp), _), _)
when Exp.equal exp deref_exp
-> let var_has_annotation =
var_has_annotation ~check_weak_captured_var pdesc is_annotation pvar
in
if var_has_annotation then obj_str := Some (Pvar.to_string pvar) ;
let procname_str_opt = attr_has_annot is_annotation tenv prop exp in
if Option.is_some procname_str_opt then obj_str := procname_str_opt ;
(* it's ok for a local with no annotation to point to deref_exp *)
var_has_annotation || Option.is_some procname_str_opt || Pvar.is_local pvar
| Sil.Hpointsto (_, Sil.Estruct (flds, _), Exp.Sizeof {typ})
-> List.for_all ~f:(is_strexp_pt_fld_with_annot tenv obj_str is_annotation typ deref_exp) flds
| _
-> true
in
if List.for_all ~f:is_pt_by_fld_or_param_with_annot prop.Prop.sigma && !obj_str <> None then
!obj_str
else None
let is_only_pt_by_fld_or_param_nullable pdesc tenv prop deref_exp =
is_only_pt_by_fld_or_param_with_annot ~check_weak_captured_var:true pdesc tenv prop deref_exp
Annotations.ia_is_nullable
let is_only_pt_by_fld_or_param_nonnull pdesc tenv prop deref_exp =
Option.is_some
(is_only_pt_by_fld_or_param_with_annot pdesc tenv prop deref_exp Annotations.ia_is_nonnull)
(** Check for dereference errors: dereferencing 0, a freed value, or an undefined value *)
let check_dereference_error tenv pdesc (prop: Prop.normal Prop.t) lexp loc =
let root = Exp.root_of_lexp lexp in
let nullable_var_opt = is_only_pt_by_fld_or_param_nullable pdesc tenv prop root in
let is_deref_of_nullable =
let is_definitely_non_null exp prop = Prover.check_disequal tenv prop exp Exp.zero in
Config.report_nullable_inconsistency && Option.is_some nullable_var_opt
&& not (is_definitely_non_null root prop)
in
let relevant_attributes_getters = [Attribute.get_resource tenv; Attribute.get_undef tenv] in
let get_relevant_attributes exp =
let rec fold_getters = function
| []
-> None
| getter :: tl ->
match getter prop exp with Some _ as some_attr -> some_attr | None -> fold_getters tl
in
fold_getters relevant_attributes_getters
in
let attribute_opt =
match get_relevant_attributes root with
| Some att
-> Some att
| None
-> (* try to remove an offset if any, and find the attribute there *)
let root_no_offset =
match root with
| Exp.BinOp ((Binop.PlusPI | Binop.PlusA | Binop.MinusPI | Binop.MinusA), base, _)
-> base
| _
-> root
in
get_relevant_attributes root_no_offset
in
( if Prover.check_zero tenv (Exp.root_of_lexp root) || is_deref_of_nullable then
let deref_str =
if is_deref_of_nullable then
match nullable_var_opt with
| Some str
-> if is_weak_captured_var pdesc str then
Localise.deref_str_weak_variable_in_block None str
else Localise.deref_str_nullable None str
| None
-> Localise.deref_str_nullable None ""
else Localise.deref_str_null None
in
let err_desc =
Errdesc.explain_dereference tenv ~use_buckets:true ~is_nullable:is_deref_of_nullable
deref_str prop loc
in
if Localise.is_parameter_not_null_checked_desc err_desc then
raise (Exceptions.Parameter_not_null_checked (err_desc, __POS__))
else if Localise.is_field_not_null_checked_desc err_desc then
raise (Exceptions.Field_not_null_checked (err_desc, __POS__))
else if Localise.is_double_lock_desc err_desc then
raise (Exceptions.Double_lock (err_desc, __POS__))
else if Localise.is_empty_vector_access_desc err_desc then
raise (Exceptions.Empty_vector_access (err_desc, __POS__))
else raise (Exceptions.Null_dereference (err_desc, __POS__)) ) ;
match attribute_opt with
| Some Apred (Adangling dk, _)
-> let deref_str = Localise.deref_str_dangling (Some dk) in
let err_desc = Errdesc.explain_dereference tenv deref_str prop (State.get_loc ()) in
raise (Exceptions.Dangling_pointer_dereference (Some dk, err_desc, __POS__))
| Some Apred (Aundef (s, _, undef_loc, _), _)
-> if Config.angelic_execution then ()
else
let deref_str = Localise.deref_str_undef (s, undef_loc) in
let err_desc = Errdesc.explain_dereference tenv deref_str prop loc in
raise (Exceptions.Skip_pointer_dereference (err_desc, __POS__))
| Some Apred (Aresource ({ra_kind= Rrelease} as ra), _)
-> let deref_str = Localise.deref_str_freed ra in
let err_desc = Errdesc.explain_dereference tenv ~use_buckets:true deref_str prop loc in
raise (Exceptions.Use_after_free (err_desc, __POS__))
| _
-> if Prover.check_equal tenv Prop.prop_emp (Exp.root_of_lexp root) Exp.minus_one then
let deref_str = Localise.deref_str_dangling None in
let err_desc = Errdesc.explain_dereference tenv deref_str prop loc in
raise (Exceptions.Dangling_pointer_dereference (None, err_desc, __POS__))
(* Check that an expression representin an objc block can be null and raise a [B1] null exception.*)
(* It's used to check that we don't call possibly null blocks *)
let check_call_to_objc_block_error tenv pdesc prop fun_exp loc =
let is_this = function
| Exp.Lvar pvar
-> let {ProcAttributes.is_objc_instance_method; is_cpp_instance_method} =
Procdesc.get_attributes pdesc
in
is_objc_instance_method && Pvar.is_self pvar || is_cpp_instance_method && Pvar.is_this pvar
| _
-> false
in
let fun_exp_may_be_null () =
(* may be null if we don't know if it is definitely not null *)
not (Prover.check_disequal tenv prop (Exp.root_of_lexp fun_exp) Exp.zero)
in
let try_explaining_exp e =
(* when e is a temp var, try to find the pvar defining e*)
match e with
| Exp.Var id -> (
match Errdesc.find_ident_assignment (State.get_node ()) id with
| Some (_, e')
-> e'
| None
-> e )
| _
-> e
in
let get_exp_called () =
(* Exp called in the block's function call*)
match State.get_instr () with
| Some Sil.Call (_, Exp.Var id, _, _, _)
-> Errdesc.find_ident_assignment (State.get_node ()) id
| _
-> None
in
let is_fun_exp_captured_var () =
(* Called expression is a captured variable of the block *)
match get_exp_called () with
| Some (_, Exp.Lvar pvar)
-> (* pvar is the block *)
let name = Pvar.get_name pvar in
List.exists ~f:(fun (cn, _) -> Mangled.equal name cn) (Procdesc.get_captured pdesc)
| _
-> false
in
let is_field_deref () =
(*Called expression is a field *)
match get_exp_called () with
| Some (_, Exp.Lfield (e', fn, t))
-> let e'' = try_explaining_exp e' in
(Some (Exp.Lfield (e'', fn, t)), true)
(* the block dereferences is a field of an object*)
| Some (_, e)
-> (Some e, false)
| _
-> (None, false)
in
if Config.curr_language_is Config.Clang && fun_exp_may_be_null ()
&& not (is_fun_exp_captured_var ())
then
let deref_str = Localise.deref_str_null None in
let err_desc_nobuckets =
Errdesc.explain_dereference tenv ~is_nullable:true deref_str prop loc
in
match fun_exp with
| Exp.Var id when Ident.is_footprint id
-> (
let e_opt, is_field_deref = is_field_deref () in
let warn err_desc =
let err_desc =
Localise.error_desc_set_bucket err_desc Localise.BucketLevel.b1 Config.show_buckets
in
if is_field_deref then raise (Exceptions.Field_not_null_checked (err_desc, __POS__))
else raise (Exceptions.Parameter_not_null_checked (err_desc, __POS__))
in
match e_opt with
| Some e when is_this e
-> (* don't warn that this/self can be null *)
()
| Some e
-> warn (Localise.parameter_field_not_null_checked_desc err_desc_nobuckets e)
| _
-> warn err_desc_nobuckets )
| _
-> (* HP: fun_exp is not a footprint therefore,
either is a local or it's a modified param *)
let err_desc =
Localise.error_desc_set_bucket err_desc_nobuckets Localise.BucketLevel.b1
Config.show_buckets
in
raise (Exceptions.Null_dereference (err_desc, __POS__))
(** [rearrange lexp prop] rearranges [prop] into the form [prop' * lexp|->strexp:typ].
It returns an iterator with [lexp |-> strexp: typ] as current predicate
and the path (an [offsetlist]) which leads to [lexp] as the iterator state. *)
let rearrange ?(report_deref_errors= true) pdesc tenv lexp typ prop loc
: Sil.offset list Prop.prop_iter list =
let nlexp =
match Prop.exp_normalize_prop tenv prop lexp with
| Exp.BinOp (Binop.PlusPI, ep, e)
-> (* array access with pointer arithmetic *)
Exp.Lindex (ep, e)
| e
-> e
in
let ptr_tested_for_zero = Prover.check_disequal tenv prop (Exp.root_of_lexp nlexp) Exp.zero in
let inst = Sil.inst_rearrange (not ptr_tested_for_zero) loc (State.get_path_pos ()) in
L.d_strln ".... Rearrangement Start ...." ;
L.d_str "Exp: " ;
Sil.d_exp nlexp ;
L.d_ln () ;
L.d_str "Prop: " ;
L.d_ln () ;
Prop.d_prop prop ;
L.d_ln () ;
L.d_ln () ;
if report_deref_errors then check_dereference_error tenv pdesc prop nlexp (State.get_loc ()) ;
let pname = Procdesc.get_proc_name pdesc in
let prop' =
if Config.csl_analysis && !Config.footprint && Typ.Procname.is_java pname
&& not (Typ.Procname.is_constructor pname || Typ.Procname.is_class_initializer pname)
then add_guarded_by_constraints tenv prop lexp pdesc
else prop
in
match Prop.prop_iter_create prop' with
| None
-> if !Config.footprint then
[prop_iter_add_hpred_footprint_to_prop pname tenv prop' (nlexp, typ) inst]
else (
pp_rearrangement_error "sigma is empty" prop nlexp ;
raise (Exceptions.Symexec_memory_error __POS__) )
| Some iter
-> iter_rearrange pname tenv nlexp typ prop' iter inst