infer_clone/infer/src/clang/cTrans.ml

(*
 * 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.
 *)

(** Translates instructions: (statements and expressions) from the ast into sil *)

open Utils
open CTrans_utils
open CFrontend_utils

open CTrans_utils.Nodes
module L = Logging

module type CTrans = sig
  (** Translates instructions: (statements and expressions) from the ast into sil *)

  (** It receives the context, a list of statements from clang ast, list of custom statments *)
  (** to be added before clang statements and the exit node and it returns a list of cfg nodes *)
  (** that reporesent the translation of the stmts into sil. *)
  val instructions_trans : CContext.t -> Clang_ast_t.stmt list -> CModule_type.instr_type list ->
    Cfg.Node.t -> Cfg.Node.t list

end

module CTrans_funct(M: CModule_type.CMethod_declaration) : CTrans =
struct

  (*Returns the procname and whether is instance, according to the selector *)
  (* information and according to the method signature with the following priority: *)
  (* 1. method is a predefined model *)
  (* 2. method is found by clang's resolution*)
  (* 3. Method is found by our resolution *)
  let get_callee_objc_method context obj_c_message_expr_info act_params =
    let open CContext in
    let (selector, method_pointer_opt, mc_type) =
      CMethod_trans.get_objc_method_data obj_c_message_expr_info in
    let is_instance = mc_type != CMethod_trans.MCStatic in
    let method_kind = Procname.objc_method_kind_of_bool is_instance in
    let ms_opt =
      match method_pointer_opt with
      | Some pointer -> CMethod_trans.method_signature_of_pointer pointer
      | None -> None in
    let procname =
      match CMethod_trans.get_method_name_from_clang context.tenv ms_opt with
      | Some ms -> CMethod_signature.ms_get_name ms
      | None ->  (* fall back to our method resolution if clang's fails *)
          let class_name = CMethod_trans.get_class_name_method_call_from_receiver_kind context
              obj_c_message_expr_info act_params in
          General_utils.mk_procname_from_objc_method class_name selector method_kind in
    let class_name = Procname.c_get_class procname in
    let predefined_ms_opt =
      CTrans_models.get_predefined_model_method_signature class_name selector
        General_utils.mk_procname_from_objc_method CFrontend_config.OBJC in
    match predefined_ms_opt, ms_opt with
    | Some ms, _ ->
        ignore (CMethod_trans.create_local_procdesc context.cfg context.tenv ms [] [] is_instance);
        CMethod_signature.ms_get_name ms, CMethod_trans.MCNoVirtual
    | None, Some ms ->
        ignore (CMethod_trans.create_local_procdesc context.cfg context.tenv ms [] [] is_instance);
        if CMethod_signature.ms_is_getter ms || CMethod_signature.ms_is_setter ms then
          procname, CMethod_trans.MCNoVirtual
        else
          procname, mc_type
    | _ ->
        CMethod_trans.create_external_procdesc context.cfg procname is_instance None;
        procname, mc_type


  let add_autorelease_call context exp typ sil_loc =
    let method_name = Procname.c_get_method (Cfg.Procdesc.get_proc_name context.CContext.procdesc) in
    if !Config.arc_mode &&
       not (CTrans_utils.is_owning_name method_name) &&
       ObjcInterface_decl.is_pointer_to_objc_class context.CContext.tenv typ then
      let fname = SymExec.ModelBuiltins.__set_autorelease_attribute in
      let ret_id = Ident.create_fresh Ident.knormal in
      let stmt_call = Sil.Call([ret_id], (Sil.Const (Sil.Cfun fname)), [(exp, typ)], sil_loc, Sil.cf_default) in
      ([ret_id], [stmt_call])
    else ([], [])

  let rec is_block_expr s =
    let open Clang_ast_t in
    match s with
    | BlockExpr _ -> true
    (* the block can be wrapped in ExprWithCleanups  or ImplicitCastExpr*)
    | ImplicitCastExpr(_, [s'], _, _)
    | ExprWithCleanups(_, [s'], _, _) -> is_block_expr s'
    | _ -> false

  let objc_exp_of_type_block fun_exp_stmt =
    match fun_exp_stmt with
    | Clang_ast_t.ImplicitCastExpr(_, _, ei, _)
      when CTypes.is_block_type ei.Clang_ast_t.ei_type_ptr -> true
    | _ -> false

  (* This function add in tenv a class representing an objc block. *)
  (* An object of this class has type:*)
  (* name_of_block |-> {capture_var1:typ_of_capture_var1,... capture_varn:typ_of_capture_varn} *)
  (* It allocates one element and sets its fields with the current values of the *)
  (* captured variables. This allocated instance is used to detect retain cycles involving the block.*)
  let allocate_block trans_state block_name captured_vars loc =
    let tenv = trans_state.context.CContext.tenv in
    let procdesc = trans_state.context.CContext.procdesc in
    let procname = Cfg.Procdesc.get_proc_name procdesc in
    let mk_field_from_captured_var (var, typ) =
      let vname = Sil.pvar_get_name var in
      let qual_name = Ast_utils.make_qual_name_decl [block_name] (Mangled.to_string vname) in
      let fname = General_utils.mk_class_field_name qual_name in
      let item_annot = Sil.item_annotation_empty in
      fname, typ, item_annot in
    let fields = IList.map mk_field_from_captured_var captured_vars in
    let fields = CFrontend_utils.General_utils.sort_fields fields in
    Printing.log_out "Block %s field:\n" block_name;
    IList.iter (fun (fn, ft, _) ->
        Printing.log_out "-----> field: '%s'\n" (Ident.fieldname_to_string fn)) fields;
    let mblock = Mangled.from_string block_name in
    let block_type = Sil.Tstruct (fields, [], Csu.Class, Some mblock, [], [], []) in
    let block_name = Typename.TN_csu (Csu.Class, mblock) in
    Sil.tenv_add tenv block_name block_type;
    let trans_res = CTrans_utils.alloc_trans trans_state loc (Ast_expressions.dummy_stmt_info ()) block_type true in
    let id_block = match trans_res.exps with
      | [(Sil.Var id, t)] -> id
      | _ -> assert false in
    let block_var = Sil.mk_pvar mblock procname in
    let declare_block_local =
      Sil.Declare_locals ([(block_var, Sil.Tptr (block_type, Sil.Pk_pointer))], loc) in
    (* Adds Nullify of the temp block variable in the predecessors of the exit node. *)
    let pred_exit = Cfg.Node.get_preds (Cfg.Procdesc.get_exit_node procdesc) in
    let block_nullify_instr =
      if pred_exit = [] then
        [Sil.Nullify (block_var, loc, true)]
      else (IList.iter (fun n -> let loc = Cfg.Node.get_loc n in
                         Cfg.Node.append_instrs_temps n [Sil.Nullify(block_var, loc, true)] []) pred_exit;
            []) in
    let set_instr = Sil.Set (Sil.Lvar block_var, block_type, Sil.Var id_block, loc) in
    let create_field_exp (var, typ) =
      let id = Ident.create_fresh Ident.knormal in
      id, Sil.Letderef (id, Sil.Lvar var, typ, loc) in
    let ids, captured_instrs = IList.split (IList.map create_field_exp captured_vars) in
    let fields_ids = IList.combine fields ids in
    let set_fields = IList.map (fun ((f, t, _), id) ->
        Sil.Set (Sil.Lfield (Sil.Var id_block, f, block_type), t, Sil.Var id, loc)) fields_ids in
    (declare_block_local :: trans_res.instrs) @ [set_instr] @ captured_instrs @ set_fields @ block_nullify_instr,
    id_block :: ids

  (* From a list of expression extract blocks from tuples and *)
  (* returns block names and assignment to temp vars  *)
  let extract_block_from_tuple procname exps loc =
    let insts = ref [] in
    let ids = ref [] in
    let is_function_name t e =
      match e with
      | Sil.Const (Sil.Cfun bn) ->
          let bn'= Procname.to_string bn in
          let bn''= Mangled.from_string bn' in
          let block = Sil.Lvar (Sil.mk_pvar bn'' procname) in
          let id = Ident.create_fresh Ident.knormal in
          ids := id :: !ids;
          insts := Sil.Letderef (id, block, t, loc) :: !insts;
          [(Sil.Var id, t)]
      | _ -> [(e, t)] in
    let get_function_name t el = IList.flatten(IList.map (is_function_name t) el) in
    let rec f es =
      match es with
      | [] -> []
      | (Sil.Const(Sil.Ctuple el), (Sil.Tptr((Sil.Tfun _), _ ) as t)) :: es' ->
          get_function_name t el @ (f es')
      | e :: es' -> e :: f es' in
    (f exps, !insts, !ids)

  let collect_exprs res_trans_list =
    IList.flatten (IList.map (fun res_trans -> res_trans.exps) res_trans_list)

  (* If e is a block and the calling node has the priority then *)
  (* we need to release the priority to allow*)
  (* creation of nodes inside the block.*)
  (* At the end of block translation, we need to get the proirity back.*)
  (* the parameter f will be called with function instruction *)
  let exec_with_block_priority_exception f trans_state e stmt_info =
    if (is_block_expr e) && (PriorityNode.own_priority_node trans_state.priority stmt_info) then (
      Printing.log_out "Translating block expression by freeing the priority";
      f { trans_state with priority = Free } e)
    else f trans_state e

  (* This is the standard way of dealing with self:Class or a call [a class]. We translate it as sizeof(<type pf a>) *)
  (* The only time when we want to translate those expressions differently is when they are the first argument of    *)
  (* method calls. In that case they are not translated as expressions, but we take the type and create a static     *)
  (* method call from it. This is done in objcMessageExpr_trans. *)
  let exec_with_self_exception f trans_state stmt =
    try
      f trans_state stmt
    with Self.SelfClassException class_name ->
      let typ = CTypes_decl.type_name_to_sil_type trans_state.context.CContext.tenv class_name in
      let expanded_type = CTypes.expand_structured_type trans_state.context.CContext.tenv typ in
      { empty_res_trans with
        exps = [(Sil.Sizeof(expanded_type, Sil.Subtype.exact), Sil.Tint Sil.IULong)] }

  let add_reference_if_lvalue typ expr_info =
    if expr_info.Clang_ast_t.ei_value_kind = `LValue then
      Sil.Tptr (typ, Sil.Pk_reference)
    else typ

  (** Execute translation and then possibly adjust the type of the result of translation:
      In C++, when expression returns reference to type T, it will be lvalue to T, not T&, but
      infer needs it to be T& *)
  let exec_with_lvalue_as_reference f trans_state stmt =
    let expr_info = match Clang_ast_proj.get_expr_tuple stmt with
      | Some (_, _, ei) -> ei
      | None -> assert false in
    let res_trans = f trans_state stmt in
    let (exp, typ) = extract_exp_from_list res_trans.exps
        "[Warning] Need exactly one expression to add reference type\n" in
    { res_trans with exps = [(exp, add_reference_if_lvalue typ expr_info)] }

  (* Execute translation of e forcing to release priority (if it's not free) and then setting it back.*)
  (* This is used in conditional operators where we need to force the priority to be free for the *)
  (* computation of the expressions*)
  let exec_with_priority_exception trans_state e f =
    if PriorityNode.is_priority_free trans_state then
      f trans_state e
    else f { trans_state with priority = Free } e

  let breakStmt_trans trans_state =
    match trans_state.continuation with
    | Some bn -> { empty_res_trans with root_nodes = bn.break }
    | _ -> assert false

  let continueStmt_trans trans_state =
    match trans_state.continuation with
    | Some bn -> { empty_res_trans with root_nodes = bn.continue }
    | _ -> assert false

  let stringLiteral_trans trans_state stmt_info expr_info str =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let exp = Sil.Const (Sil.Cstr (str)) in
    { empty_res_trans with exps = [(exp, typ)]}

  (* FROM CLANG DOCS: "Implements the GNU __null extension, which is a name for a null pointer constant *)
     (* that has integral type (e.g., int or long) and is the same size and alignment as a pointer. The __null *)
     (* extension is typically  only used by system headers, which define NULL as __null in C++ rather than using 0 *)
     (* (which is an integer that may not match the size of a pointer)". So we implement it as the constant zero *)
  let gNUNullExpr_trans trans_state stmt_info expr_info =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let exp = Sil.Const (Sil.Cint (Sil.Int.zero)) in
    { empty_res_trans with exps = [(exp, typ)]}

  let nullPtrExpr_trans trans_state stmt_info expr_info =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    { empty_res_trans with exps = [(Sil.exp_null, typ)]}

  let objCSelectorExpr_trans trans_state stmt_info expr_info selector =
    stringLiteral_trans trans_state stmt_info expr_info selector

  let objCEncodeExpr_trans trans_state stmt_info expr_info type_ptr =
    stringLiteral_trans trans_state stmt_info expr_info (Ast_utils.string_of_type_ptr type_ptr)

  let objCProtocolExpr_trans trans_state stmt_info expr_info decl_ref =
    let name = (match decl_ref.Clang_ast_t.dr_name with
        | Some s -> s.Clang_ast_t.ni_name
        | _ -> "") in
    stringLiteral_trans trans_state stmt_info expr_info name

  let characterLiteral_trans trans_state stmt_info expr_info n =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let exp = Sil.Const (Sil.Cint (Sil.Int.of_int n)) in
    { empty_res_trans with exps = [(exp, typ)]}

  let floatingLiteral_trans trans_state stmt_info expr_info float_string =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let exp = Sil.Const (Sil.Cfloat (float_of_string float_string)) in
    { empty_res_trans with exps = [(exp, typ)]}

  (* Note currently we don't have support for different qual     *)
  (* type like long, unsigned long, etc                                *)
  and integerLiteral_trans trans_state stmt_info expr_info integer_literal_info =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let exp, ids =
      try
        let i = Int64.of_string integer_literal_info.Clang_ast_t.ili_value in
        let exp = Sil.exp_int (Sil.Int.of_int64 i) in
        exp, []
      with
      | Failure _ ->
          (* Parse error: return a nondeterministic value *)
          let id = Ident.create_fresh Ident.knormal in
          let exp = Sil.Var id in
          exp, [id] in
    { empty_res_trans with
      exps = [(exp, typ)];
      ids = ids; }

  let nullStmt_trans succ_nodes stmt_info =
    { empty_res_trans with root_nodes = succ_nodes }

  (* The stmt seems to be always empty *)
  let unaryExprOrTypeTraitExpr_trans trans_state stmt_info expr_info unary_expr_or_type_trait_expr_info =
    let tenv = trans_state.context.CContext.tenv in
    let typ = CTypes_decl.type_ptr_to_sil_type tenv expr_info.Clang_ast_t.ei_type_ptr in
    match unary_expr_or_type_trait_expr_info.Clang_ast_t.uttei_kind with
    | `SizeOf ->
        let tp = Ast_utils.type_from_unary_expr_or_type_trait_expr_info unary_expr_or_type_trait_expr_info in
        let sizeof_typ =
          match tp with
          | Some tp -> CTypes_decl.type_ptr_to_sil_type tenv tp
          | None -> typ in (* Some default type since the type is missing *)
        { empty_res_trans with exps = [(Sil.Sizeof(sizeof_typ, Sil.Subtype.exact), sizeof_typ)]}
    | k -> Printing.log_stats
             "\nWARNING: Missing translation of Uniry_Expression_Or_Trait of kind: %s . Expression ignored, returned -1... \n"
             (Clang_ast_j.string_of_unary_expr_or_type_trait_kind k);
        { empty_res_trans with exps =[(Sil.exp_minus_one, typ)]}

  (* search the label into the hashtbl - create a fake node eventually *)
  (* connect that node with this stmt *)
  let gotoStmt_trans trans_state stmt_info label_name =
    let sil_loc = CLocation.get_sil_location stmt_info trans_state.context in
    let root_node' = GotoLabel.find_goto_label trans_state.context label_name sil_loc in
    { empty_res_trans with root_nodes = [root_node']; leaf_nodes = trans_state.succ_nodes }

  let function_deref_trans trans_state decl_ref =
    let open CContext in
    let context = trans_state.context in
    let name_info, decl_ptr, type_ptr = get_info_from_decl_ref decl_ref in
    let name = Ast_utils.get_qualified_name name_info in
    let typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
    let pname =
      if CTrans_models.is_modeled_builtin name then
        Procname.from_string_c_fun (CFrontend_config.infer ^ name)
      else CMethod_trans.create_procdesc_with_pointer context decl_ptr None name type_ptr in
    let address_of_function = not context.CContext.is_callee_expression in
    (* If we are not translating a callee expression, *)
    (* then the address of the function is being taken.*)
    (* As e.g. in fun_ptr = foo; *)
    let non_mangled_func_name =
      if name = CFrontend_config.malloc &&
         (!CFrontend_config.language = CFrontend_config.OBJC ||
          !CFrontend_config.language = CFrontend_config.OBJCPP) then
        SymExec.ModelBuiltins.malloc_no_fail
      else Procname.from_string_c_fun name in
    let is_builtin = SymExec.function_is_builtin non_mangled_func_name in
    if is_builtin then (* malloc, free, exit, scanf, ... *)
      { empty_res_trans with exps = [(Sil.Const (Sil.Cfun non_mangled_func_name), typ)] }
    else
      begin
        if address_of_function then Cfg.set_procname_priority context.cfg pname;
        { empty_res_trans with exps = [(Sil.Const (Sil.Cfun pname), typ)] }
      end

  let var_deref_trans trans_state stmt_info decl_ref =
    let open CContext in
    let context = trans_state.context in
    let _, _, type_ptr = get_info_from_decl_ref decl_ref in
    let typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
    let procname = Cfg.Procdesc.get_proc_name context.procdesc in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let pvar = CVar_decl.sil_var_of_decl_ref context decl_ref procname in
    CContext.add_block_static_var context procname (pvar, typ);
    let e = Sil.Lvar pvar in
    let exps = if Self.is_var_self pvar (CContext.is_objc_method context) then
        let curr_class = CContext.get_curr_class context in
        if (CTypes.is_class typ) then
          raise (Self.SelfClassException (CContext.get_curr_class_name curr_class))
        else
          let typ = CTypes.add_pointer_to_typ
              (CTypes_decl.get_type_curr_class context.tenv curr_class) in
          [(e, typ)]
      else [(e, typ)] in
    Printing.log_out "\n\n PVAR ='%s'\n\n" (Sil.pvar_to_string pvar);
    let res_trans = { empty_res_trans with exps = exps } in
    if CTypes.is_reference_type type_ptr then
      (* dereference pvar due to the behavior of reference types in clang's AST *)
      dereference_value_from_result sil_loc res_trans ~strip_pointer:true
    else res_trans

  let field_deref_trans trans_state pre_trans_result decl_ref =
    let open CContext in
    let context = trans_state.context in
    let name_info, _, type_ptr = get_info_from_decl_ref decl_ref in
    Printing.log_out "!!!!! Dealing with field '%s' @." name_info.Clang_ast_t.ni_name;
    let field_typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
    let (obj_sil, class_typ) = extract_exp_from_list pre_trans_result.exps
        "WARNING: in Field dereference we expect to know the object\n" in
    let class_typ =
      match class_typ with
      | Sil.Tptr (t, _) -> CTypes.expand_structured_type context.CContext.tenv t
      | t -> t in
    Printing.log_out "Type is  '%s' @." (Sil.typ_to_string class_typ);
    let field_name = General_utils.mk_class_field_name name_info in
    let exp = Sil.Lfield (obj_sil, field_name, class_typ) in
    { pre_trans_result with exps = [(exp, field_typ)] }

  let method_deref_trans trans_state pre_trans_result decl_ref =
    let open CContext in
    let context = trans_state.context in
    let name_info, decl_ptr, type_ptr = get_info_from_decl_ref decl_ref in
    let method_name = Ast_utils.get_unqualified_name name_info in
    let class_name = Ast_utils.get_class_name_from_member name_info in
    Printing.log_out "!!!!! Dealing with method '%s' @." method_name;
    let method_typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
    let is_instance_method =
      match CMethod_trans.method_signature_of_pointer decl_ptr with
      | Some ms -> CMethod_signature.ms_is_instance ms
      | _ -> true in (* might happen for methods that are not exported yet (some templates). *)
    let extra_exps = if is_instance_method then (
        (* pre_trans_result.exps may contain expr for 'this' parameter:*)
        (* if it comes from CXXMemberCallExpr it will be there *)
        (* if it comes from CXXOperatorCallExpr it won't be there and will be added later *)
        assert (IList.length pre_trans_result.exps <= 1);
        pre_trans_result.exps)
      else
        (* don't add 'this' expression for static methods *)
        [] in
    (* consider using context.CContext.is_callee_expression to deal with pointers to methods? *)
    (* unlike field access, for method calls there is no need to expand class type *)
    let pname = CMethod_trans.create_procdesc_with_pointer context decl_ptr (Some class_name)
        method_name type_ptr in
    let method_exp = (Sil.Const (Sil.Cfun pname), method_typ) in
    Cfg.set_procname_priority context.CContext.cfg pname;
    { pre_trans_result with exps = [method_exp] @ extra_exps }

  let destructor_deref_trans trans_state pvar_trans_result class_type_ptr =
    let open Clang_ast_t in
    let destruct_decl_ref_opt = match Ast_utils.get_decl_from_typ_ptr class_type_ptr with
      | Some CXXRecordDecl (_, _, _ , _, _, _, _, cxx_record_info)
      | Some ClassTemplateSpecializationDecl (_, _, _, _, _, _, _, cxx_record_info) ->
          cxx_record_info.xrdi_destructor
      | _ -> None in
    match destruct_decl_ref_opt with
    | Some decl_ref -> method_deref_trans trans_state pvar_trans_result decl_ref
    | None -> empty_res_trans


  let cxxThisExpr_trans trans_state stmt_info expr_info =
    let context = trans_state.context in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let tp = expr_info.Clang_ast_t.ei_type_ptr in
    let procname = Cfg.Procdesc.get_proc_name context.CContext.procdesc in
    let name = CFrontend_config.this in
    let pvar = Sil.mk_pvar (Mangled.from_string name) procname in
    let exp = Sil.Lvar pvar in
    let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv tp in
    let exps =  [(exp, typ)] in
    (* there is no cast operation in AST, but backend needs it *)
    dereference_value_from_result sil_loc { empty_res_trans with exps = exps } ~strip_pointer:false

  let rec labelStmt_trans trans_state stmt_info stmt_list label_name =
    (* go ahead with the translation *)
    let res_trans = match stmt_list with
      | [stmt] ->
          instruction trans_state stmt
      | _ -> assert false (* expected a stmt or at most a compoundstmt *) in
    (* create the label root node into the hashtbl *)
    let sil_loc = CLocation.get_sil_location stmt_info trans_state.context in
    let root_node' = GotoLabel.find_goto_label trans_state.context label_name sil_loc in
    Cfg.Node.set_succs_exn root_node' res_trans.root_nodes [];
    { empty_res_trans with root_nodes = [root_node']; leaf_nodes = trans_state.succ_nodes }

  and decl_ref_trans trans_state pre_trans_result stmt_info expr_info decl_ref =
    let open CContext in
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let decl_kind = decl_ref.Clang_ast_t.dr_kind in
    match decl_kind with
    | `EnumConstant -> enum_constant_trans trans_state decl_ref
    | `Function -> function_deref_trans trans_state decl_ref
    | `Var | `ImplicitParam | `ParmVar -> var_deref_trans trans_state stmt_info decl_ref
    | `Field | `ObjCIvar -> field_deref_trans trans_state pre_trans_result decl_ref
    | `CXXMethod | `CXXConstructor -> method_deref_trans trans_state pre_trans_result decl_ref
    | _ ->
        let print_error decl_kind =
          Printing.log_stats
            "Warning: Decl ref expression %s with pointer %d still needs to be translated "
            (Clang_ast_j.string_of_decl_kind decl_kind)
            decl_ref.Clang_ast_t.dr_decl_pointer in
        print_error decl_kind; assert false

  and declRefExpr_trans trans_state stmt_info expr_info decl_ref_expr_info e =
    let open CContext in
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let decl_ref = match decl_ref_expr_info.Clang_ast_t.drti_decl_ref with
      | Some dr -> dr
      | None -> assert false in
    decl_ref_trans trans_state empty_res_trans stmt_info expr_info decl_ref

  (* evaluates an enum constant *)
  and enum_const_eval context enum_constant_pointer prev_enum_constant_opt zero =
    match Ast_utils.get_decl enum_constant_pointer with
    | Some Clang_ast_t.EnumConstantDecl (_, _, _, enum_constant_decl_info) ->
        (match enum_constant_decl_info.Clang_ast_t.ecdi_init_expr with
         | Some stmt ->
             expression_trans context stmt
               "WARNING: Expression in Enumeration constant not found\n"
         | None ->
             match prev_enum_constant_opt with
             | Some prev_constant_pointer ->
                 let previous_exp = get_enum_constant_expr context prev_constant_pointer in
                 CArithmetic_trans.sil_const_plus_one previous_exp
             | None -> zero)
    | _ -> zero

  (* get the sil value of the enum constant from the map or by evaluating it *)
  and get_enum_constant_expr context enum_constant_pointer =
    let zero = Sil.Const (Sil.Cint Sil.Int.zero) in
    try
      let (prev_enum_constant_opt, sil_exp_opt) =
        Ast_utils.get_enum_constant_exp enum_constant_pointer in
      match sil_exp_opt with
      | Some exp -> exp
      | None ->
          let exp = enum_const_eval context enum_constant_pointer prev_enum_constant_opt zero in
          Ast_utils.update_enum_map enum_constant_pointer exp;
          exp
    with Not_found -> zero

  and enum_constant_trans trans_state decl_ref =
    let context = trans_state.context in
    let _, _, type_ptr = get_info_from_decl_ref decl_ref in
    let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv type_ptr in
    let const_exp = get_enum_constant_expr context decl_ref.Clang_ast_t.dr_decl_pointer in
    { empty_res_trans with exps = [(const_exp, typ)] }

  and arraySubscriptExpr_trans trans_state stmt_info expr_info stmt_list =
    let typ = CTypes_decl.get_type_from_expr_info expr_info trans_state.context.CContext.tenv in
    let array_stmt, idx_stmt = (match stmt_list with
        | [a; i] -> a, i  (* Assumption: the statement list contains 2 elements,
                             the first is the array expr and the second the index *)
        | _ -> assert false) in (* Let's get notified if the assumption is wrong...*)
    let res_trans_a = instruction trans_state array_stmt in
    let res_trans_idx = instruction trans_state idx_stmt in
    let (a_exp, a_typ) = extract_exp_from_list res_trans_a.exps
        "WARNING: In ArraySubscriptExpr there was a problem in translating array exp.\n" in
    let (i_exp, i_typ) = extract_exp_from_list res_trans_idx.exps
        "WARNING: In ArraySubscriptExpr there was a problem in translating index exp.\n" in
    let array_exp = Sil.Lindex (a_exp, i_exp) in

    let root_nodes =
      if res_trans_a.root_nodes <> []
      then res_trans_a.root_nodes
      else res_trans_idx.root_nodes in
    let leaf_nodes =
      if res_trans_idx.leaf_nodes <> []
      then res_trans_idx.leaf_nodes
      else res_trans_a.leaf_nodes in

    if res_trans_idx.root_nodes <> []
    then
      IList.iter
        (fun n -> Cfg.Node.set_succs_exn n res_trans_idx.root_nodes [])
        res_trans_a.leaf_nodes;

    (* Note the order of res_trans_idx.ids @ res_trans_a.ids is important. *)
    (* We expect to use only res_trans_idx.ids in construction of other operation.                  *)
    (* res_trans_a.ids is passed to be Removed.*)
    { root_nodes = root_nodes;
      leaf_nodes = leaf_nodes;
      ids = res_trans_idx.ids @ res_trans_a.ids;
      instrs = res_trans_a.instrs @ res_trans_idx.instrs;
      exps = [(array_exp, typ)]}

  and binaryOperator_trans trans_state binary_operator_info stmt_info expr_info stmt_list =
    let open Clang_ast_t in
    let procname = Cfg.Procdesc.get_proc_name trans_state.context.CContext.procdesc in
    let bok = (Clang_ast_j.string_of_binary_operator_kind binary_operator_info.Clang_ast_t.boi_kind) in
    Printing.log_out "  BinaryOperator '%s' " bok;
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let context = trans_state.context in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv expr_info.Clang_ast_t.ei_type_ptr in
    (match stmt_list with
     | [s1; ImplicitCastExpr (stmt, [CompoundLiteralExpr (cle_stmt_info, stmts, expr_info)], _, cast_expr_info)] ->
         let decl_ref  = get_decl_ref_info s1 in
         let pvar = CVar_decl.sil_var_of_decl_ref context decl_ref procname in
         let var_res_trans = { empty_res_trans with exps = [(Sil.Lvar pvar, typ)] } in
         let res_trans_tmp =
           initListExpr_trans trans_state var_res_trans stmt_info expr_info stmts in
         { res_trans_tmp with leaf_nodes =[]}
     | [s1; s2] -> (* Assumption: We expect precisely 2 stmt corresponding to the 2 operands*)
         let rhs_owning_method = CTrans_utils.is_owning_method s2 in
         (* NOTE: we create a node only if required. In that case this node *)
         (* becomes the successor of the nodes that may be created when     *)
         (* translating the operands.                                       *)
         let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
         let trans_state' = { trans_state_pri with succ_nodes = [] } in
         let res_trans_e1 = exec_with_self_exception instruction trans_state' s1 in
         let res_trans_e2 =
           (* translation of s2 is done taking care of block special case *)
           exec_with_block_priority_exception (exec_with_self_exception instruction) trans_state' s2 stmt_info in
         let (sil_e1, sil_typ1) = extract_exp_from_list res_trans_e1.exps "\nWARNING: Missing LHS operand in BinOp. Returning -1. Fix needed...\n" in
         let (sil_e2, sil_typ2) = extract_exp_from_list res_trans_e2.exps "\nWARNING: Missing RHS operand in BinOp. Returning -1. Fix needed...\n" in
         let exp_op, instr_bin, ids_bin =
           CArithmetic_trans.binary_operation_instruction context binary_operator_info sil_e1 typ sil_e2 sil_loc rhs_owning_method in


         (* Create a node if the priority if free and there are instructions *)
         let creating_node =
           (PriorityNode.own_priority_node trans_state_pri.priority stmt_info) &&
           (IList.length instr_bin >0) in

         let extra_instrs, extra_ids, exp_to_parent =
           if (is_binary_assign_op binary_operator_info)
           (* assignment operator result is lvalue in CPP, rvalue in C, hence the difference *)
           && (not (General_utils.is_cpp_translation !CFrontend_config.language))
           && ((not creating_node) || (is_return_temp trans_state.continuation)) then (
             (* We are in this case when an assignment is inside        *)
             (* another operator that creates a node. Eg. another       *)
             (* assignment.  *)
             (* As no node is created here ids are passed to the parent *)
             let id = Ident.create_fresh Ident.knormal in
             let res_instr = Sil.Letderef (id, sil_e1, sil_typ1, sil_loc) in
             [res_instr], [id], Sil.Var id
           ) else (
             [], [], exp_op) in

         let binop_res_trans = { empty_res_trans with
                                 ids = ids_bin @ extra_ids;
                                 instrs = instr_bin @ extra_instrs
                               } in
         let all_res_trans = [res_trans_e1; res_trans_e2; binop_res_trans] in
         let nname = "BinaryOperatorStmt: "^ (CArithmetic_trans.bin_op_to_string binary_operator_info) in
         let res_trans_to_parent = PriorityNode.compute_results_to_parent trans_state_pri sil_loc nname stmt_info all_res_trans in
         { res_trans_to_parent with exps = [(exp_to_parent, sil_typ1)] }
     | _ -> assert false) (* Binary operator should have two operands*)

  and callExpr_trans trans_state si stmt_list expr_info =
    let context = trans_state.context in
    let function_type = CTypes_decl.get_type_from_expr_info expr_info context.CContext.tenv in
    let procname = Cfg.Procdesc.get_proc_name context.CContext.procdesc in
    let sil_loc = CLocation.get_sil_location si context in
    (* First stmt is the function expr and the rest are params *)
    let fun_exp_stmt, params_stmt = (match stmt_list with
        | fe :: params -> fe, params
        | _ -> assert false) in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state si in
    (* claim priority if no ancestors has claimed priority before *)
    let context_callee = { context with CContext.is_callee_expression = true } in
    let trans_state_callee = { trans_state_pri with context = context_callee; succ_nodes = [] } in
    let is_call_to_block = objc_exp_of_type_block fun_exp_stmt in
    let res_trans_callee = instruction trans_state_callee fun_exp_stmt in
    (* As we may have nodes coming from different parameters we need to  *)
    (* call instruction for each parameter and collect the results       *)
    (* afterwards. The 'instructions' function does not do that          *)
    let trans_state_param =
      { trans_state_pri with succ_nodes = [] } in
    let (sil_fe, typ_fe) = extract_exp_from_list res_trans_callee.exps
        "WARNING: The translation of fun_exp did not return an expression. Returning -1. NEED TO BE FIXED" in
    let callee_pname_opt =
      match sil_fe with
      | Sil.Const (Sil.Cfun pn) ->
          Some pn
      | _ -> None (* function pointer *) in
    let should_translate_args =
      match callee_pname_opt with
      | Some pn ->
          (* we cannot translate the arguments of this builtin because preprocessing copies them *)
          (* verbatim from a call to a different function, and they might be side-effecting *)
          (Procname.to_string pn) <> CFrontend_config.builtin_object_size
      | _ -> true in
    let params_stmt = if should_translate_args then
        CTrans_utils.assign_default_params params_stmt fun_exp_stmt
      else [] in
    let result_trans_subexprs =
      let instruction' = exec_with_self_exception (exec_with_lvalue_as_reference instruction) in
      let res_trans_p = IList.map (instruction' trans_state_param) params_stmt in
      res_trans_callee :: res_trans_p in
    let sil_fe, is_cf_retain_release = CTrans_models.builtin_predefined_model fun_exp_stmt sil_fe in
    if CTrans_models.is_assert_log sil_fe then
      if Config.report_custom_error then
        CTrans_utils.trans_assertion_failure sil_loc context
      else
        CTrans_utils.trans_assume_false sil_loc context trans_state.succ_nodes
    else
      let act_params =
        let params = IList.tl (collect_exprs result_trans_subexprs) in
        if IList.length params = IList.length params_stmt then
          params
        else (Printing.log_err
                "WARNING: stmt_list and res_trans_par.exps must have same size. NEED TO BE FIXED\n\n";
              fix_param_exps_mismatch params_stmt params) in
      let act_params = if is_cf_retain_release then
          (Sil.Const (Sil.Cint Sil.Int.one), Sil.Tint Sil.IBool) :: act_params
        else act_params in
      match CTrans_utils.builtin_trans trans_state_pri sil_loc si function_type callee_pname_opt with
      | Some builtin -> builtin
      | None ->
          let ret_id, call_instr =
            match cast_trans context act_params sil_loc callee_pname_opt function_type with
            | Some (id, instr, _) -> [id], instr
            | None ->
                let ret_id = if (Sil.typ_equal function_type Sil.Tvoid) then []
                  else [Ident.create_fresh Ident.knormal] in
                let call_flags = { Sil.cf_default with Sil.cf_is_objc_block = is_call_to_block; } in
                let call_instr = Sil.Call(ret_id, sil_fe, act_params, sil_loc, call_flags) in
                ret_id, call_instr in

          let res_trans_call = { empty_res_trans with ids = ret_id; instrs = [call_instr] } in
          let nname = "Call "^(Sil.exp_to_string sil_fe) in
          let all_res_trans = result_trans_subexprs @ [res_trans_call] in
          let res_trans_to_parent =
            PriorityNode.compute_results_to_parent trans_state_pri sil_loc nname si all_res_trans in
          (match callee_pname_opt with
           | Some callee_pname ->
               let open CContext in
               if not (SymExec.function_is_builtin callee_pname) then
                 begin
                   Cg.add_edge context.cg procname callee_pname;
                 end
           | None -> ());
          (match ret_id with
           | [] -> { res_trans_to_parent with exps =[] }
           | [ret_id'] -> { res_trans_to_parent with exps =[(Sil.Var ret_id', function_type)] }
           | _ -> assert false) (* by construction of red_id, we cannot be in this case *)

  and cxx_method_construct_call_trans trans_state_pri result_trans_callee params_stmt
      si function_type =
    let open CContext in
    let context = trans_state_pri.context in
    let procname = Cfg.Procdesc.get_proc_name context.procdesc in
    let sil_loc = CLocation.get_sil_location si context in
    (* first for method address, second for 'this' expression *)
    assert ((IList.length result_trans_callee.exps) = 2);
    let (sil_method, typ_method) = IList.hd result_trans_callee.exps in
    let callee_pname = match sil_method with
      | Sil.Const (Sil.Cfun pn) -> pn
      | _ -> assert false (* method pointer not implemented, this shouldn't happen *) in
    (* As we may have nodes coming from different parameters we need to  *)
    (* call instruction for each parameter and collect the results       *)
    (* afterwards. The 'instructions' function does not do that          *)
    let trans_state_param =
      { trans_state_pri with succ_nodes = [] } in
    let result_trans_subexprs =
      let instruction' = exec_with_self_exception (exec_with_lvalue_as_reference instruction) in
      let res_trans_p = IList.map (instruction' trans_state_param) params_stmt in
      result_trans_callee :: res_trans_p in
    (* first expr is method address, rest are params including 'this' parameter *)
    let actual_params = IList.tl (collect_exprs result_trans_subexprs) in
    let ret_id = if (Sil.typ_equal function_type Sil.Tvoid) then []
      else [Ident.create_fresh Ident.knormal] in
    let call_flags = {
      Sil.cf_virtual = false (* TODO t7725350 *);
      Sil.cf_interface = false;
      Sil.cf_noreturn = false;
      Sil.cf_is_objc_block = false;
    } in
    let call_instr = Sil.Call (ret_id, sil_method, actual_params, sil_loc, call_flags) in
    let res_trans_call = { empty_res_trans with ids = ret_id; instrs = [call_instr] } in
    let nname = "Call " ^ (Sil.exp_to_string sil_method) in
    let all_res_trans = result_trans_subexprs @ [res_trans_call] in
    let result_trans_to_parent =
      PriorityNode.compute_results_to_parent trans_state_pri sil_loc nname si all_res_trans in
    Cg.add_edge context.CContext.cg procname callee_pname;
    match ret_id with
    | [] -> { result_trans_to_parent with exps = [] }
    | [ret_id'] -> { result_trans_to_parent with exps = [(Sil.Var ret_id', function_type)] }
    | _ -> assert false (* by construction of red_id, we cannot be in this case *)

  and cxxMemberCallExpr_trans trans_state si stmt_list expr_info =
    let context = trans_state.context in
    (* Structure is the following: *)
    (* CXXMemberCallExpr: first stmt is method+this expr and the rest are normal params *)
    (* CXXOperatorCallExpr: First stmt is method/function deref without this expr and the *)
    (*                      rest are params, possibly including 'this' *)
    let fun_exp_stmt, params_stmt = (match stmt_list with
        | fe :: params -> fe, assign_default_params params fe
        | _ -> assert false) in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state si in
    (* claim priority if no ancestors has claimed priority before *)
    let trans_state_callee = { trans_state_pri with succ_nodes = [] } in
    let result_trans_callee = instruction trans_state_callee fun_exp_stmt in
    let function_type = CTypes_decl.get_type_from_expr_info expr_info context.CContext.tenv in
    cxx_method_construct_call_trans trans_state_pri result_trans_callee params_stmt
      si function_type

  and cxxConstructExpr_trans trans_state this_res_trans expr =
    match expr with
    | Clang_ast_t.CXXConstructExpr (si, params_stmt, ei, cxx_constr_info) ->
        let trans_state_pri = PriorityNode.try_claim_priority_node trans_state si in
        let decl_ref = cxx_constr_info.Clang_ast_t.xcei_decl_ref in
        let res_trans_callee = decl_ref_trans trans_state this_res_trans si ei decl_ref in
        let params_stmt' = assign_default_params params_stmt expr in
        cxx_method_construct_call_trans trans_state_pri res_trans_callee params_stmt' si
          Sil.Tvoid
    | _ -> assert false

  and cxx_destructor_call_trans trans_state si this_res_trans class_type_ptr =
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state si in
    let res_trans_callee = destructor_deref_trans trans_state this_res_trans class_type_ptr in
    if res_trans_callee.exps <> [] then
      cxx_method_construct_call_trans trans_state_pri res_trans_callee [] si Sil.Tvoid
    else empty_res_trans

  and objCMessageExpr_trans_special_cases trans_state si obj_c_message_expr_info stmt_list
      expr_info method_type trans_state_pri sil_loc act_params =
    let context = trans_state.context in
    let receiver_kind = obj_c_message_expr_info.Clang_ast_t.omei_receiver_kind in
    let selector = obj_c_message_expr_info.Clang_ast_t.omei_selector in
    (* class method *)
    if selector = CFrontend_config.class_method && CTypes.is_class method_type then
      let class_name = CMethod_trans.get_class_name_method_call_from_receiver_kind context
          obj_c_message_expr_info act_params in
      raise (Self.SelfClassException class_name)
      (* alloc or new *)
    else if (selector = CFrontend_config.alloc) || (selector = CFrontend_config.new_str) then
      match receiver_kind with
      | `Class type_ptr ->
          let class_opt =
            CMethod_trans.get_class_name_method_call_from_clang obj_c_message_expr_info in
          Some (new_or_alloc_trans trans_state_pri sil_loc si type_ptr class_opt selector)
      | _ -> None
      (* assertions *)
    else if CTrans_models.is_handleFailureInMethod selector then
      if Config.report_custom_error then
        Some (CTrans_utils.trans_assertion_failure sil_loc context)
      else Some (CTrans_utils.trans_assume_false sil_loc context trans_state.succ_nodes)
    else None


  (* If the first argument of the call is self in a static context, remove it as an argument *)
  (* and change the call from instance to static *)
  and objCMessageExpr_deal_with_static_self trans_state_param stmt_list obj_c_message_expr_info =
    match stmt_list with
    | stmt :: rest ->
        let obj_c_message_expr_info, fst_res_trans =
          try
            let fst_res_trans = instruction trans_state_param stmt in
            obj_c_message_expr_info, fst_res_trans
          with Self.SelfClassException class_name ->
            let pointer = obj_c_message_expr_info.Clang_ast_t.omei_decl_pointer in
            let selector = obj_c_message_expr_info.Clang_ast_t.omei_selector in
            let obj_c_message_expr_info =
              Ast_expressions.make_obj_c_message_expr_info_class selector class_name pointer in
            obj_c_message_expr_info, empty_res_trans in
        let instruction' =
          exec_with_self_exception (exec_with_lvalue_as_reference instruction) in
        let l = IList.map (instruction' trans_state_param) rest in
        obj_c_message_expr_info, fst_res_trans :: l
    | [] -> obj_c_message_expr_info, [empty_res_trans]

  and objCMessageExpr_trans trans_state si obj_c_message_expr_info stmt_list expr_info =
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let context = trans_state.context in
    let sil_loc = CLocation.get_sil_location si context in
    let method_type = CTypes_decl.get_type_from_expr_info expr_info context.CContext.tenv in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state si in
    let trans_state_param = { trans_state_pri with succ_nodes = [] } in
    let obj_c_message_expr_info, res_trans_subexpr_list =
      objCMessageExpr_deal_with_static_self trans_state_param stmt_list obj_c_message_expr_info in
    let subexpr_exprs = collect_exprs res_trans_subexpr_list in
    match objCMessageExpr_trans_special_cases trans_state si obj_c_message_expr_info stmt_list
            expr_info method_type trans_state_pri sil_loc subexpr_exprs with
    | Some res -> res
    | None ->
        let procname = Cfg.Procdesc.get_proc_name context.CContext.procdesc in
        let callee_name, method_call_type = get_callee_objc_method context obj_c_message_expr_info
            subexpr_exprs in
        let res_trans_add_self = Self.add_self_parameter_for_super_instance context procname sil_loc
            obj_c_message_expr_info in
        let res_trans_subexpr_list = res_trans_add_self :: res_trans_subexpr_list in
        let subexpr_exprs = collect_exprs res_trans_subexpr_list in
        let is_virtual = method_call_type = CMethod_trans.MCVirtual in
        Cg.add_edge context.CContext.cg procname callee_name;

        let param_exps, instr_block_param, ids_block_param =
          extract_block_from_tuple procname subexpr_exprs sil_loc in

        let ret_id =
          if Sil.typ_equal method_type Sil.Tvoid then []
          else [Ident.create_fresh Ident.knormal] in
        let call_flags = { Sil.cf_default with Sil.cf_virtual = is_virtual; } in
        let stmt_call =
          Sil.Call (ret_id, (Sil.Const (Sil.Cfun callee_name)), param_exps, sil_loc, call_flags) in
        let selector = obj_c_message_expr_info.Clang_ast_t.omei_selector in
        let nname = "Message Call: "^selector in
        let res_trans_call = { empty_res_trans with
                               ids = ids_block_param @ ret_id;
                               instrs = instr_block_param @ [stmt_call];
                             } in
        let all_res_trans = res_trans_subexpr_list @ [res_trans_call] in
        let res_trans_to_parent =
          PriorityNode.compute_results_to_parent trans_state_pri sil_loc nname si all_res_trans in
        match ret_id with
        | [] -> { res_trans_to_parent with exps = [] }
        | [ret_id'] -> { res_trans_to_parent with exps = [(Sil.Var ret_id', method_type)] }
        | _ -> assert false (* by construction of red_id, we cannot be in this case *)

  and dispatch_function_trans trans_state stmt_info stmt_list ei n =
    Printing.log_out "\n Call to a dispatch function treated as special case...\n";
    let procname = Cfg.Procdesc.get_proc_name trans_state.context.CContext.procdesc in
    let pvar = CFrontend_utils.General_utils.get_next_block_pvar procname in
    let transformed_stmt, tp =
      Ast_expressions.translate_dispatch_function (Sil.pvar_to_string pvar) stmt_info stmt_list ei n in
    instruction trans_state transformed_stmt

  and block_enumeration_trans trans_state stmt_info stmt_list ei =
    let declare_nullify_vars loc res_state roots preds (pvar, typ) =
      (* Add nullify of the temp block var to the last node (predecessor or the successor nodes)*)
      IList.iter (fun n -> Cfg.Node.append_instrs_temps n [Sil.Nullify(pvar, loc, true)] []) preds in

    Printing.log_out "\n Call to a block enumeration function treated as special case...\n@.";
    let procname = Cfg.Procdesc.get_proc_name trans_state.context.CContext.procdesc in
    let pvar = CFrontend_utils.General_utils.get_next_block_pvar procname in
    let transformed_stmt, vars_to_register =
      Ast_expressions.translate_block_enumerate (Sil.pvar_to_string pvar) stmt_info stmt_list ei in
    let pvars_types = IList.map (fun (v, pointer, tp) ->
        let pvar = Sil.mk_pvar (Mangled.from_string v) procname in
        let typ = CTypes_decl.type_ptr_to_sil_type trans_state.context.CContext.tenv tp in
        (pvar, typ)) vars_to_register in
    let loc = CLocation.get_sil_location stmt_info trans_state.context in
    let res_state = instruction trans_state transformed_stmt in
    let preds = IList.flatten (IList.map (fun n -> Cfg.Node.get_preds n) trans_state.succ_nodes) in
    IList.iter (declare_nullify_vars loc res_state res_state.root_nodes preds) pvars_types;
    res_state

  and compoundStmt_trans trans_state stmt_info stmt_list =
    instructions trans_state (IList.rev stmt_list)

  and conditionalOperator_trans trans_state stmt_info stmt_list expr_info =
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let procname = Cfg.Procdesc.get_proc_name context.CContext.procdesc in
    let mk_temp_var id =
      Sil.mk_pvar (Mangled.from_string ("SIL_temp_conditional___"^(string_of_int id))) procname in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let do_branch branch stmt var_typ prune_nodes join_node pvar =
      let trans_state_pri = PriorityNode.force_claim_priority_node trans_state stmt_info in
      let trans_state' = { trans_state_pri with succ_nodes = [] } in
      let res_trans_b = instruction trans_state' stmt in
      let (e', e'_typ) = extract_exp_from_list res_trans_b.exps
          "\nWARNING: Missing branch expression for Conditional operator. Need to be fixed\n" in
      let set_temp_var = [
        Sil.Declare_locals([(pvar, var_typ)], sil_loc);
        Sil.Set (Sil.Lvar pvar, var_typ, e', sil_loc)
      ] in
      let tmp_var_res_trans = { empty_res_trans with instrs = set_temp_var } in
      let trans_state'' = { trans_state' with succ_nodes = [join_node] } in
      let all_res_trans = [res_trans_b; tmp_var_res_trans] in
      let res_trans = PriorityNode.compute_results_to_parent trans_state'' sil_loc
          "ConditinalStmt Branch" stmt_info all_res_trans in
      let prune_nodes_t, prune_nodes_f = IList.partition is_true_prune_node prune_nodes in
      let prune_nodes' = if branch then prune_nodes_t else prune_nodes_f in
      IList.iter (fun n -> Cfg.Node.set_succs_exn n res_trans.root_nodes []) prune_nodes' in
    (match stmt_list with
     | [cond; exp1; exp2] ->
         let typ =
           CTypes_decl.type_ptr_to_sil_type context.CContext.tenv expr_info.Clang_ast_t.ei_type_ptr in
         let var_typ = add_reference_if_lvalue typ expr_info in
         let join_node = create_node (Cfg.Node.Join_node) [] [] sil_loc context in
         Cfg.Node.set_succs_exn join_node succ_nodes [];
         let pvar = mk_temp_var (Cfg.Node.get_id join_node) in
         let continuation' = mk_cond_continuation trans_state.continuation in
         let trans_state' = { trans_state with continuation = continuation'; succ_nodes = [] } in
         let res_trans_cond = exec_with_priority_exception trans_state' cond cond_trans in
         (* Note: by contruction prune nodes are leafs_nodes_cond *)
         do_branch true exp1 var_typ res_trans_cond.leaf_nodes join_node pvar;
         do_branch false exp2 var_typ res_trans_cond.leaf_nodes join_node pvar;
         let id = Ident.create_fresh Ident.knormal in
         let instrs = [
           Sil.Letderef (id, Sil.Lvar pvar, var_typ, sil_loc);
           Sil.Nullify (pvar, sil_loc, true)
         ] in
         { root_nodes = res_trans_cond.root_nodes;
           leaf_nodes = [join_node];
           ids = [id];
           instrs = instrs;
           exps = [(Sil.Var id, typ)]
         }
     | _ -> assert false)

  (* Translate a condition for if/loops statement. It shorts-circuit and/or. *)
  (* The invariant is that the translation of a condition always contains (at least) *)
  (* the prune nodes. Moreover these are always the leaf nodes of the translation. *)
  and cond_trans trans_state cond =
    let context = trans_state.context in
    let si, _ = Clang_ast_proj.get_stmt_tuple cond in
    let sil_loc = CLocation.get_sil_location si context in
    let mk_prune_node b e ids ins =
      create_prune_node b e ids ins sil_loc (Sil.Ik_if) context in
    let extract_exp el =
      extract_exp_from_list el
        "\nWARNING: Missing expression for Conditional operator. Need to be fixed" in
    (* this function translate cond without doing shortcircuit *)
    let no_short_circuit_cond () =
      Printing.log_out " No short-circuit condition\n";
      let res_trans_cond =
        if is_null_stmt cond then {
          empty_res_trans with exps = [(Sil.Const (Sil.Cint Sil.Int.one), (Sil.Tint Sil.IBool))]
        }
        (* Assumption: If it's a null_stmt, it is a loop with no bound, so we set condition to 1 *)
        else
          instruction trans_state cond in
      let e', instrs' = define_condition_side_effects context res_trans_cond.exps res_trans_cond.instrs sil_loc in
      let prune_t = mk_prune_node true e' res_trans_cond.ids instrs' in
      let prune_f = mk_prune_node false e' res_trans_cond.ids instrs' in
      IList.iter (fun n' -> Cfg.Node.set_succs_exn n' [prune_t; prune_f] []) res_trans_cond.leaf_nodes;
      let rnodes = if (IList.length res_trans_cond.root_nodes) = 0 then
          [prune_t; prune_f]
        else res_trans_cond.root_nodes in
      { root_nodes = rnodes; leaf_nodes =[prune_t; prune_f]; ids = res_trans_cond.ids; instrs = instrs'; exps = e' } in

    (* This function translate (s1 binop s2) doing shortcircuit for '&&' and '||' *)
    (* At the high level it does cond_trans s1; cond_trans s2; glue_nodes *)
    (* The glue_nodes partitions the prune nodes of s1's translation.*)
    (* Some of them need to go to the statement to be executed after the *)
    (* condition (prune_to_short_c) and others to the root nodes of the *)
    (* translation of s2 (i.e., the case when we need to fully evaluate*)
    (* the condition to decide its truth value). *)
    let short_circuit binop s1 s2 =
      let res_trans_s1 = cond_trans trans_state s1 in
      let prune_nodes_t, prune_nodes_f = IList.partition is_true_prune_node res_trans_s1.leaf_nodes in
      let res_trans_s2 = cond_trans trans_state s2 in
      (* prune_to_s2 is the prune node that is connected with the root node of the *)
      (* translation of s2.*)
      (* prune_to_short_c is the prune node that is connected directly with the branch *)
      (* where the control flow goes in case of short circuit *)
      let prune_to_s2, prune_to_short_c = (match binop with
          | Sil.LAnd -> prune_nodes_t, prune_nodes_f
          | Sil.LOr -> prune_nodes_f, prune_nodes_t
          | _ -> assert false) in
      IList.iter (fun n -> Cfg.Node.set_succs_exn n res_trans_s2.root_nodes []) prune_to_s2;
      let root_nodes_to_parent =
        if (IList.length res_trans_s1.root_nodes) = 0 then res_trans_s1.leaf_nodes else res_trans_s1.root_nodes in
      let (exp1, typ1) = extract_exp res_trans_s1.exps in
      let (exp2, typ2) = extract_exp res_trans_s2.exps in
      let e_cond = Sil.BinOp (binop, exp1, exp2) in
      { root_nodes = root_nodes_to_parent;
        leaf_nodes = prune_to_short_c@res_trans_s2.leaf_nodes;
        ids = res_trans_s1.ids@res_trans_s2.ids;
        instrs = res_trans_s1.instrs@res_trans_s2.instrs;
        exps = [(e_cond, typ1)] } in
    Printing.log_out "Translating Condition for Conditional/Loop \n";
    let open Clang_ast_t in
    match cond with
    | BinaryOperator(si, [s1; s2], expr_info, boi) ->
        (match boi.Clang_ast_t.boi_kind with
         | `LAnd -> short_circuit (Sil.LAnd) s1 s2
         | `LOr -> short_circuit (Sil.LOr) s1 s2
         | _ -> no_short_circuit_cond ())
    | ParenExpr(_,[s], _) -> (* condition can be wrapped in parenthesys *)
        cond_trans trans_state s
    | _ -> no_short_circuit_cond ()

  and declStmt_in_condition_trans trans_state decl_stmt res_trans_cond =
    match decl_stmt with
    | Clang_ast_t.DeclStmt(stmt_info, stmt_list, decl_list) ->
        let trans_state_decl = { trans_state with
                                 succ_nodes = res_trans_cond.root_nodes
                               } in
        declStmt_trans trans_state_decl decl_list stmt_info
    | _ -> res_trans_cond

  and ifStmt_trans trans_state stmt_info stmt_list =
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let join_node = create_node (Cfg.Node.Join_node) [] [] sil_loc context in
    Cfg.Node.set_succs_exn join_node succ_nodes [];
    let trans_state' = { trans_state with succ_nodes = [join_node] } in
    let do_branch branch stmt_branch prune_nodes =
      (* leaf nodes are ignored here as they will be already attached to join_node *)
      let res_trans_b = instruction trans_state' stmt_branch in
      let nodes_branch = (match res_trans_b.root_nodes with
          | [] -> [create_node (Cfg.Node.Stmt_node "IfStmt Branch" ) res_trans_b.ids res_trans_b.instrs sil_loc context]
          | _ -> res_trans_b.root_nodes) in
      let prune_nodes_t, prune_nodes_f = IList.partition is_true_prune_node prune_nodes in
      let prune_nodes' = if branch then prune_nodes_t else prune_nodes_f in
      IList.iter (fun n -> Cfg.Node.set_succs_exn n nodes_branch []) prune_nodes';
      res_trans_b.ids in
    (match stmt_list with
     | [decl_stmt; cond; stmt1; stmt2] ->
         (* set the flat to inform that we are translating a condition of a if *)
         let continuation' = mk_cond_continuation trans_state.continuation in
         let trans_state'' = { trans_state with
                               continuation = continuation';
                               succ_nodes = []
                             } in
         let res_trans_cond = cond_trans trans_state'' cond in
         let res_trans_decl = declStmt_in_condition_trans trans_state decl_stmt res_trans_cond in
         (* Note: by contruction prune nodes are leafs_nodes_cond *)
         let ids_t = do_branch true stmt1 res_trans_cond.leaf_nodes in
         let ids_f = do_branch false stmt2 res_trans_cond.leaf_nodes in
         {
           root_nodes = res_trans_decl.root_nodes;
           leaf_nodes = [join_node];
           ids = res_trans_decl.ids @ res_trans_cond.ids @ ids_t @ ids_f;
           instrs = [];
           exps = []
         }
     | _ -> assert false)

  (* Assumption: the CompoundStmt can be made of different stmts, not just CaseStmts *)
  and switchStmt_trans trans_state stmt_info switch_stmt_list =
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let continuation = trans_state.continuation in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let open Clang_ast_t in
    match switch_stmt_list with
    | [decl_stmt; cond; CompoundStmt(stmt_info, stmt_list)] ->
        let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
        let trans_state' ={ trans_state_pri with succ_nodes = []} in
        let res_trans_cond_tmp = instruction trans_state' cond in
        let switch_special_cond_node =
          let node_kind = Cfg.Node.Stmt_node "Switch_stmt" in
          create_node node_kind [] res_trans_cond_tmp.instrs sil_loc context in
        IList.iter (fun n' -> Cfg.Node.set_succs_exn n' [switch_special_cond_node] []) res_trans_cond_tmp.leaf_nodes;
        let root_nodes =
          if res_trans_cond_tmp.root_nodes <> [] then res_trans_cond_tmp.root_nodes
          else [switch_special_cond_node] in
        let (switch_e_cond', switch_e_cond'_typ) =
          extract_exp_from_list res_trans_cond_tmp.exps
            "\nWARNING: The condition of the SwitchStmt is not singleton. Need to be fixed\n" in
        let res_trans_cond = { res_trans_cond_tmp with
                               root_nodes = root_nodes;
                               leaf_nodes = [switch_special_cond_node]
                             } in
        let res_trans_decl = declStmt_in_condition_trans trans_state decl_stmt res_trans_cond in
        let trans_state_no_pri = if PriorityNode.own_priority_node trans_state_pri.priority stmt_info then
            { trans_state_pri with priority = Free }
          else trans_state_pri in
        let switch_exit_point = succ_nodes in
        let continuation' =
          match continuation with
          | Some cont -> Some { cont with break = switch_exit_point }
          | None -> Some { break = switch_exit_point; continue = []; return_temp = false } in
        let trans_state'' = { trans_state_no_pri with continuation = continuation'} in
        let merge_into_cases stmt_list = (* returns list_of_cases * before_any_case_instrs *)
          let rec aux rev_stmt_list acc cases =
            (match rev_stmt_list with
             | CaseStmt (info, a :: b :: (CaseStmt x) :: c) :: rest -> (* case x: case y: ... *)
                 if c <> [] then assert false; (* empty case with nested case, then followed by some instructions *)
                 let rest' = [CaseStmt(info, a :: b :: [])] @ rest in
                 let rev_stmt_list' = (CaseStmt x) :: rest' in
                 aux rev_stmt_list' acc cases
             | CaseStmt (info, a :: b :: (DefaultStmt x) :: c) :: rest ->
                 (* case x: default: ... *)
                 if c <> [] then assert false; (* empty case with nested case, then followed by some instructions *)
                 let rest' = [CaseStmt(info, a :: b :: [])] @ rest in
                 let rev_stmt_list' = (DefaultStmt x) :: rest' in
                 aux rev_stmt_list' acc cases
             | DefaultStmt (info, (CaseStmt x) :: c) :: rest -> (* default: case x: ... *)
                 if c <> [] then assert false; (* empty case with nested case, then followed by some instructions *)
                 let rest' = [DefaultStmt(info, [])] @ rest in
                 let rev_stmt_list' = (CaseStmt x) :: rest' in
                 aux rev_stmt_list' acc cases
             | CaseStmt (info, a :: b :: c) :: rest ->
                 aux rest [] (CaseStmt(info, a :: b :: c @ acc) :: cases)
             | DefaultStmt (info, c) :: rest -> (* default is always the last in the list *)
                 aux rest [] (DefaultStmt(info, c @ acc) :: cases)
             | x :: rest ->
                 aux rest (x :: acc) cases
             | [] ->
                 cases, acc) in
          aux (IList.rev stmt_list) [] [] in
        let list_of_cases, pre_case_stmts = merge_into_cases stmt_list in
        let rec connected_instruction rev_instr_list successor_nodes =
          (* returns the entry point of the translated set of instr *)
          match rev_instr_list with
          | [] -> successor_nodes
          | instr :: rest ->
              let trans_state''' = { trans_state'' with succ_nodes = successor_nodes } in
              let res_trans_instr = instruction trans_state''' instr in
              let instr_entry_points = res_trans_instr.root_nodes in
              connected_instruction rest instr_entry_points in
        let rec translate_and_connect_cases cases next_nodes next_prune_nodes =
          let create_prune_nodes_for_case case =
            match case with
            | CaseStmt (stmt_info, case_const :: _ :: _) ->
                let trans_state_pri =
                  PriorityNode.try_claim_priority_node trans_state'' stmt_info in
                let res_trans_case_const = instruction trans_state_pri case_const in
                let e_const = res_trans_case_const.exps in
                let e_const' =
                  match e_const with
                  | [(head, typ)] -> head
                  | _ -> assert false in
                let sil_eq_cond = Sil.BinOp (Sil.Eq, switch_e_cond', e_const') in
                let sil_loc = CLocation.get_sil_location stmt_info context in
                let true_prune_node =
                  create_prune_node true [(sil_eq_cond, switch_e_cond'_typ)]
                    res_trans_case_const.ids res_trans_case_const.instrs
                    sil_loc Sil.Ik_switch context in
                let false_prune_node =
                  create_prune_node false [(sil_eq_cond, switch_e_cond'_typ)]
                    res_trans_case_const.ids res_trans_case_const.instrs
                    sil_loc Sil.Ik_switch context in
                (true_prune_node, false_prune_node)
            | _ -> assert false in
          match cases with (* top-down to handle default cases *)
          | [] -> next_nodes, next_prune_nodes
          | CaseStmt(stmt_info, _ :: _ :: case_content) as case :: rest ->
              let last_nodes, last_prune_nodes = translate_and_connect_cases rest next_nodes next_prune_nodes in
              let case_entry_point = connected_instruction (IList.rev case_content) last_nodes in
              (* connects between cases, then continuation has priority about breaks *)
              let prune_node_t, prune_node_f = create_prune_nodes_for_case case in
              Cfg.Node.set_succs_exn prune_node_t case_entry_point [];
              Cfg.Node.set_succs_exn prune_node_f last_prune_nodes [];
              case_entry_point, [prune_node_t; prune_node_f]
          | DefaultStmt(stmt_info, default_content) :: rest ->
              let sil_loc = CLocation.get_sil_location stmt_info context in
              let placeholder_entry_point =
                create_node (Cfg.Node.Stmt_node "DefaultStmt_placeholder") [] [] sil_loc context in
              let last_nodes, last_prune_nodes = translate_and_connect_cases rest next_nodes [placeholder_entry_point] in
              let default_entry_point = connected_instruction (IList.rev default_content) last_nodes in
              Cfg.Node.set_succs_exn placeholder_entry_point default_entry_point [];
              default_entry_point, last_prune_nodes
          | _ -> assert false in
        let top_entry_point, top_prune_nodes = translate_and_connect_cases list_of_cases succ_nodes succ_nodes in
        let _ = connected_instruction (IList.rev pre_case_stmts) top_entry_point in
        Cfg.Node.set_succs_exn switch_special_cond_node top_prune_nodes [];
        let top_nodes = res_trans_decl.root_nodes in
        IList.iter (fun n' -> Cfg.Node.append_instrs_temps n' [] res_trans_cond.ids) succ_nodes; (* succ_nodes will remove the temps *)
        { root_nodes = top_nodes; leaf_nodes = succ_nodes; ids = []; instrs = []; exps =[]}
    | _ -> assert false

  and stmtExpr_trans trans_state stmt_info stmt_list expr_info =
    let context = trans_state.context in
    let stmt = extract_stmt_from_singleton stmt_list "ERROR: StmtExpr should have only one statement.\n" in
    let res_trans_stmt = instruction trans_state stmt in
    let idl = res_trans_stmt.ids in
    let exps' = IList.rev res_trans_stmt.exps in
    match exps' with
    | (last, typ) :: _ ->
        (* The StmtExpr contains a single CompoundStmt node, which it evaluates and *)
        (* takes the value of the last subexpression.*)
        (* Exp returned by StmtExpr is always a RValue. So we need to assign to a temp and return the temp.*)
        let id = Ident.create_fresh Ident.knormal in
        let loc = CLocation.get_sil_location stmt_info context in
        let instr' = Sil.Letderef (id, last, typ, loc) in
        { root_nodes = res_trans_stmt.root_nodes;
          leaf_nodes = res_trans_stmt.leaf_nodes;
          ids = id :: idl;
          instrs = res_trans_stmt.instrs @ [instr'];
          exps = [(Sil.Var id, typ)]}
    | _ -> assert false

  and loop_instruction trans_state loop_kind stmt_info =
    let outer_continuation = trans_state.continuation in
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let join_node = create_node Cfg.Node.Join_node [] [] sil_loc context in
    let continuation = Some { break = succ_nodes; continue = [join_node]; return_temp = false } in
    (* set the flat to inform that we are translating a condition of a if *)
    let continuation_cond = mk_cond_continuation outer_continuation in
    let init_incr_nodes =
      match loop_kind with
      | Loops.For (init, decl_stmt, cond, incr, body) ->
          let trans_state' = {
            trans_state with
            succ_nodes = [join_node];
            continuation = continuation;
          } in
          let res_trans_init = instruction trans_state' init in
          let res_trans_incr = instruction trans_state' incr in
          Some (res_trans_init.root_nodes, res_trans_incr.root_nodes)
      | _ -> None in
    let cond_stmt = Loops.get_cond loop_kind in
    let trans_state_cond = {
      trans_state with
      continuation = continuation_cond;
      succ_nodes = [];
    } in
    let res_trans_cond = cond_trans trans_state_cond cond_stmt in
    let decl_stmt_opt = match loop_kind with
      | Loops.For (_, decl_stmt, _, _, _) -> Some decl_stmt
      | Loops.While (decl_stmt_opt, _, _) -> decl_stmt_opt
      | _ -> None in
    let res_trans_decl = match decl_stmt_opt with
      | Some decl_stmt -> declStmt_in_condition_trans trans_state decl_stmt res_trans_cond
      | _ -> res_trans_cond in
    let body_succ_nodes =
      match loop_kind with
      | Loops.For _ -> (match init_incr_nodes with
          | Some (nodes_init, nodes_incr) -> nodes_incr
          | None -> assert false)
      | Loops.While _ -> [join_node]
      | Loops.DoWhile _ -> res_trans_cond.root_nodes in
    let body_continuation = match continuation, init_incr_nodes with
      | Some c, Some (nodes_init, nodes_incr) ->
          Some { c with continue = nodes_incr }
      | _ -> continuation in
    let res_trans_body =
      let trans_state_body =
        { trans_state with
          succ_nodes = body_succ_nodes;
          continuation = body_continuation } in
      instruction trans_state_body (Loops.get_body loop_kind) in
    let join_succ_nodes =
      match loop_kind with
      | Loops.For _ | Loops.While _ -> res_trans_decl.root_nodes
      | Loops.DoWhile _ -> res_trans_body.root_nodes in
    (* Note: prune nodes are by contruction the res_trans_cond.leaf_nodes *)
    let prune_nodes_t, prune_nodes_f = IList.partition is_true_prune_node res_trans_cond.leaf_nodes in
    let prune_t_succ_nodes =
      match loop_kind with
      | Loops.For _ | Loops.While _ -> res_trans_body.root_nodes
      | Loops.DoWhile _ -> [join_node] in
    Cfg.Node.set_succs_exn join_node join_succ_nodes [];
    IList.iter (fun n -> Cfg.Node.set_succs_exn n prune_t_succ_nodes []) prune_nodes_t;
    IList.iter (fun n -> Cfg.Node.set_succs_exn n succ_nodes []) prune_nodes_f;
    let root_nodes =
      match loop_kind with
      | Loops.For _ ->
          (match init_incr_nodes with | Some (nodes_init, nodes_incr) -> nodes_init | None -> assert false)
      | Loops.While _ | Loops.DoWhile _ -> [join_node] in
    { empty_res_trans with root_nodes = root_nodes; leaf_nodes = prune_nodes_f }

  and forStmt_trans trans_state init decl_stmt cond incr body stmt_info =
    let for_kind = Loops.For (init, decl_stmt, cond, incr, body) in
    loop_instruction trans_state for_kind stmt_info

  and whileStmt_trans trans_state decl_stmt cond body stmt_info =
    let while_kind = Loops.While (Some decl_stmt, cond, body) in
    loop_instruction trans_state while_kind stmt_info

  and doStmt_trans trans_state stmt_info cond body =
    let dowhile_kind = Loops.DoWhile (cond, body) in
    loop_instruction trans_state dowhile_kind stmt_info

  (* Fast iteration for colection
     for (type_it i in collection) { body }
     is translate as
     {
      i = type_next_object();
      while(i != nil) { body; i = type_next_object();}
     }
  *)
  and objCForCollectionStmt_trans trans_state item items body stmt_info =
    let _ = instruction trans_state item in
    (* Here we do ast transformation, so we don't need the value of the translation of the *)
    (* variable item but we still need to add the variable to the locals *)
    let assign_next_object, cond = Ast_expressions.make_next_object_exp stmt_info item items in
    let body' = Clang_ast_t.CompoundStmt (stmt_info, [body; assign_next_object]) in
    let null_stmt = Clang_ast_t.NullStmt (stmt_info,[]) in
    let loop = Clang_ast_t.WhileStmt (stmt_info, [null_stmt; cond; body']) in
    instruction trans_state (Clang_ast_t.CompoundStmt (stmt_info, [assign_next_object; loop]))

  and initListExpr_trans trans_state var_res_trans stmt_info expr_info stmts =
    let var_exp, _ = extract_exp_from_list var_res_trans.exps
        "WARNING: InitListExpr expects one variable expression" in
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let rec collect_right_hand_exprs ts stmt = match stmt with
      | Clang_ast_t.InitListExpr (_ , stmts , _) ->
          IList.flatten (IList.map (collect_right_hand_exprs ts) stmts)
      | _ ->
          let trans_state' = { ts with succ_nodes = []} in
          let res_trans_stmt = instruction trans_state' stmt in
          let (exp, typ) = extract_exp_from_list res_trans_stmt.exps
              "WARNING: in InitListExpr we expect the translation of each stmt to return one expression.\n" in
          let is_owning_method = CTrans_utils.is_owning_method stmt in
          let is_method_call = CTrans_utils.is_method_call stmt in
          [(res_trans_stmt.ids, res_trans_stmt.instrs, exp, is_method_call, is_owning_method, typ)] in
    let rec collect_left_hand_exprs e typ tns =
      let open General_utils in
      match typ with
      | Sil.Tvar tn ->
          (match Sil.tenv_lookup context.CContext.tenv tn with
           | Some (Sil.Tstruct _ as str) -> collect_left_hand_exprs e str tns
           | Some ((Sil.Tvar typename) as tvar) ->
               if (StringSet.mem (Typename.to_string typename) tns) then
                 [[(e, typ)]]
               else
                 collect_left_hand_exprs e tvar (StringSet.add (Typename.to_string typename) tns)
           | _ -> [[(e, typ)]] (*This case is an error, shouldn't happen.*))
      | Sil.Tstruct (struct_fields, _, _, _, _, _, _) as type_struct ->
          let lh_exprs = IList.map ( fun (fieldname, fieldtype, _) ->
              Sil.Lfield (e, fieldname, type_struct) )
              struct_fields in
          let lh_types = IList.map ( fun (fieldname, fieldtype, _) -> fieldtype)
              struct_fields in
          IList.map (fun (e, t) -> IList.flatten (collect_left_hand_exprs e t tns)) (zip lh_exprs lh_types)
      | Sil.Tarray (arrtyp, Sil.Const (Sil.Cint n)) ->
          let size = Sil.Int.to_int n in
          let indices = list_range 0 (size - 1) in
          let index_constants = IList.map
              (fun i -> (Sil.Const (Sil.Cint (Sil.Int.of_int i))))
              indices in
          let lh_exprs = IList.map
              (fun index_expr -> Sil.Lindex (e, index_expr))
              index_constants in
          let lh_types = replicate size arrtyp in
          IList.map (fun (e, t) -> IList.flatten (collect_left_hand_exprs e t tns)) (zip lh_exprs lh_types)
      | _ -> [ [(e, typ)] ] in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
    let var_type = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv expr_info.Clang_ast_t.ei_type_ptr in
    let lh = IList.flatten (collect_left_hand_exprs var_exp var_type Utils.StringSet.empty) in
    let rh = IList.flatten (IList.map (collect_right_hand_exprs trans_state_pri) stmts ) in
    if (IList.length rh != IList.length lh) then (
      (* If the right hand expressions are not as many as the left hand expressions something's wrong *)
      { empty_res_trans with root_nodes = succ_nodes }
    ) else (
      (* Creating new instructions by assigning right hand side to left hand side expressions *)
      let sil_loc = CLocation.get_sil_location stmt_info context in
      let big_zip = IList.map
          (fun ( (lh_exp, lh_t), (_, _, rh_exp, is_method_call, rhs_owning_method, rh_t) ) ->
             let is_pointer_object = ObjcInterface_decl.is_pointer_to_objc_class context.CContext.tenv rh_t in
             if !Config.arc_mode && (is_method_call || is_pointer_object) then
               (* In arc mode, if it's a method call or we are initializing with a pointer to objc class *)
               (* we need to add retain/release *)
               let (e, instrs, ids) =
                 CArithmetic_trans.assignment_arc_mode context lh_exp lh_t rh_exp sil_loc rhs_owning_method true in
               ([(e, lh_t)], instrs, ids)
             else
               ([], [Sil.Set (lh_exp, lh_t, rh_exp, sil_loc)], []))
          (General_utils.zip lh rh) in
      let rh_instrs = IList.flatten ( IList.map (fun (_, instrs, _, _, _, _) -> instrs) rh) in
      let assign_instrs = IList.flatten(IList.map (fun (_, instrs, _) -> instrs) big_zip) in
      let assign_ids = IList.flatten(IList.map (fun (_, _, ids) -> ids) big_zip) in
      let instructions = IList.append (rh_instrs) assign_instrs in
      let rh_ids = IList.flatten ( IList.map (fun (ids, _, _, _, _, _) -> ids) rh) in
      let ids = IList.append (rh_ids) assign_ids in
      if PriorityNode.own_priority_node trans_state_pri.priority stmt_info then (
        let node_kind = Cfg.Node.Stmt_node "InitListExp" in
        let node = create_node node_kind (ids) (instructions) sil_loc context in
        Cfg.Node.set_succs_exn node succ_nodes [];
        {
          root_nodes = [node];
          leaf_nodes = [];
          ids = rh_ids;
          instrs = instructions;
          exps = [(var_exp, var_type)];
        }
      ) else {
        root_nodes = [];
        leaf_nodes = [];
        ids = rh_ids;
        instrs = instructions;
        exps = [(var_exp, var_type)];
      }
    )

  and init_expr_trans trans_state var_res_trans var_stmt_info init_expr_opt =
    let open Clang_ast_t in
    match init_expr_opt with
    | None -> { empty_res_trans with root_nodes = trans_state.succ_nodes } (* Nothing to do if no init expression *)
    | Some (ImplicitValueInitExpr (_, stmt_list, _)) ->
        (* Seems unclear what it does, so let's keep an eye on the stmts *)
        (* and report a warning if it finds a non empty list of stmts *)
        (match stmt_list with
         | [] -> ()
         | _ -> Printing.log_stats "\n!!!!WARNING: found statement <\"ImplicitValueInitExpr\"> with non-empty stmt_list.\n");
        { empty_res_trans with root_nodes = trans_state.succ_nodes }
    | Some (InitListExpr (stmt_info , stmts , expr_info))
    | Some (ExprWithCleanups (_, [InitListExpr (stmt_info , stmts , expr_info)], _, _)) ->
        initListExpr_trans trans_state var_res_trans stmt_info expr_info stmts
    | Some (CXXConstructExpr _ as expr) ->
        cxxConstructExpr_trans trans_state var_res_trans expr
    | Some ie -> (*For init expr, translate how to compute it and assign to the var*)
        let stmt_info, _ = Clang_ast_proj.get_stmt_tuple ie in
        let context = trans_state.context in
        let sil_loc = CLocation.get_sil_location stmt_info context in
        let var_exp, var_typ = extract_exp_from_list var_res_trans.exps
            "WARNING: init_expr_trans expects one variable expression" in
        let trans_state_pri = PriorityNode.try_claim_priority_node trans_state var_stmt_info in
        (* if ie is a block the translation need to be done with the block special cases by exec_with_block_priority*)
        let res_trans_ie =
          let trans_state' = { trans_state_pri with succ_nodes = [] } in
          let instruction' =
            exec_with_self_exception (exec_with_lvalue_as_reference instruction) in
          exec_with_block_priority_exception instruction' trans_state' ie var_stmt_info in
        let (sil_e1', ie_typ) = extract_exp_from_list res_trans_ie.exps
            "WARNING: In DeclStmt we expect only one expression returned in recursive call\n" in
        let rhs_owning_method = CTrans_utils.is_owning_method ie in
        let _, instrs_assign, ids_assign =
          if !Config.arc_mode &&
             (CTrans_utils.is_method_call ie || ObjcInterface_decl.is_pointer_to_objc_class context.CContext.tenv ie_typ) then
            (* In arc mode, if it's a method call or we are initializing with a pointer to objc class *)
            (* we need to add retain/release *)
            let (e, instrs, ids) =
              CArithmetic_trans.assignment_arc_mode context var_exp ie_typ sil_e1' sil_loc rhs_owning_method true in
            ([(e, ie_typ)], instrs, ids)
          else ([], [Sil.Set (var_exp, ie_typ, sil_e1', sil_loc)], []) in
        let res_trans_assign = { empty_res_trans with
                                 ids = ids_assign;
                                 instrs = instrs_assign } in
        let all_res_trans = [var_res_trans; res_trans_ie; res_trans_assign] in
        let res_trans = PriorityNode.compute_results_to_parent trans_state_pri sil_loc "DeclStmt"
            var_stmt_info all_res_trans in
        { res_trans with exps =  [(var_exp, ie_typ)] }

  and collect_all_decl trans_state var_decls next_nodes stmt_info =
    let open Clang_ast_t in
    let context = trans_state.context in
    let procdesc = context.CContext.procdesc in
    let procname = Cfg.Procdesc.get_proc_name procdesc in
    let do_var_dec (di, var_name, type_ptr, vdi) next_node =
      let var_decl = VarDecl (di, var_name, type_ptr, vdi) in
      let pvar = CVar_decl.sil_var_of_decl context var_decl procname in
      let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv type_ptr in
      let typ_ptr = Sil.Tptr (typ, Sil.Pk_pointer) in
      CVar_decl.add_var_to_locals procdesc var_decl typ pvar;
      let var_res_trans = { empty_res_trans with exps = [(Sil.Lvar pvar, typ_ptr)] } in
      let trans_state' = { trans_state with succ_nodes = next_node } in
      init_expr_trans trans_state' var_res_trans stmt_info vdi.Clang_ast_t.vdi_init_expr in

    match var_decls with
    | [] -> { empty_res_trans with root_nodes = next_nodes }
    | VarDecl (di, n, tp, vdi) :: var_decls' ->
        (* Var are defined when procdesc is created, here we only take care of initialization*)
        let res_trans_vd = collect_all_decl trans_state var_decls' next_nodes stmt_info in
        let res_trans_tmp = do_var_dec (di, n, tp, vdi) res_trans_vd.root_nodes in
        { root_nodes = res_trans_tmp.root_nodes; leaf_nodes = [];
          ids = res_trans_tmp.ids @ res_trans_vd.ids;
          instrs = res_trans_tmp.instrs @ res_trans_vd.instrs;
          exps = res_trans_tmp.exps @ res_trans_vd.exps }
    | CXXRecordDecl _ :: var_decls' (*C++/C record decl treated in the same way *)
    | RecordDecl _ :: var_decls' ->
        (* Record declaration is done in the beginning when procdesc is defined.*)
        collect_all_decl trans_state var_decls' next_nodes stmt_info
    | _ -> assert false

  (* stmt_list is ignored because it contains the same instructions as *)
  (* the init expression. We use the latter info.                      *)
  and declStmt_trans trans_state decl_list stmt_info =
    let succ_nodes = trans_state.succ_nodes in
    let res_trans =
      let open Clang_ast_t in
      match decl_list with
      | VarDecl _ :: _ ->  (* Case for simple variable declarations*)
          collect_all_decl trans_state decl_list succ_nodes stmt_info
      | CXXRecordDecl _ :: _ (*C++/C record decl treated in the same way *)
      | RecordDecl _ :: _ -> (* Case for struct *)
          collect_all_decl trans_state decl_list succ_nodes stmt_info
      | _ ->
          Printing.log_stats
            "WARNING: In DeclStmt found an unknown declaration type. RETURNING empty list of declaration. NEED TO BE FIXED";
          empty_res_trans in
    { res_trans with leaf_nodes = [] }

  and objCPropertyRefExpr_trans trans_state stmt_info stmt_list =
    match stmt_list with
    | [stmt] -> instruction trans_state stmt
    | _ -> assert false

  (* For OpaqueValueExpr we return the translation generated from its source expression*)
  and opaqueValueExpr_trans trans_state stmt_info opaque_value_expr_info =
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    match opaque_value_expr_info.Clang_ast_t.ovei_source_expr with
    | Some stmt -> instruction trans_state stmt
    | _ -> assert false

  (* NOTE: This translation has several hypothesis. Need to be verified when we have more*)
  (* experience with this construct. Assert false will help to see if we encounter programs*)
  (* that do not conform with this hypothesis.*)
  (* Hypotheses:*)
  (* 1. stmt_list is composed by 2 parts: the first element is a syntactic description of the*)
  (* expression. The rest of the list has a semantic caracterization of the expression and*)
  (* defines how that expression is going to be implemented at runtime. *)
  (* 2. the semantic description is composed by a list of OpaqueValueExpr that define the *)
  (* various expressions involved and one finale expression that define how the final value of*)
  (* the PseudoObjectExpr is obtained. All the OpaqueValueExpr will be part of the last expression.*)
  (* So they can be skipped. *)
  (* For example: 'x.f = a' when 'f' is a property will be translated with a call to f's setter [x f:a]*)
  (* the stmt_list will be [x.f = a; x; a; CallToSetter] Among all element of the list we only need*)
  (* to translate the CallToSetter which is how x.f = a is actually implemented by the runtime.*)
  and pseudoObjectExpr_trans trans_state stmt_info stmt_list =
    let open Clang_ast_t in
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let rec do_semantic_elements el =
      let open Clang_ast_t in
      match el with
      | OpaqueValueExpr _ :: el' -> do_semantic_elements el'
      | stmt :: _ -> instruction trans_state stmt
      | _ -> assert false in
    match stmt_list with
    | syntactic_form :: semantic_form ->
        do_semantic_elements semantic_form
    | _ -> assert false

  (* Cast expression are treated the same apart from the cast operation kind*)
  and cast_exprs_trans trans_state stmt_info stmt_list expr_info cast_expr_info is_objc_bridged =
    let context = trans_state.context in
    Printing.log_out "  priority node free = '%s'\n@."
      (string_of_bool (PriorityNode.is_priority_free trans_state));
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let stmt = extract_stmt_from_singleton stmt_list
        "WARNING: In CastExpr There must be only one stmt defining the expression to be cast.\n" in
    let res_trans_stmt = instruction trans_state stmt in
    let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv expr_info.Clang_ast_t.ei_type_ptr in
    let cast_kind = cast_expr_info.Clang_ast_t.cei_cast_kind in
    (* This gives the differnece among cast operations kind*)
    let cast_ids, cast_inst, cast_exp = cast_operation context cast_kind res_trans_stmt.exps typ sil_loc is_objc_bridged in
    { root_nodes = res_trans_stmt.root_nodes;
      leaf_nodes = res_trans_stmt.leaf_nodes;
      ids = res_trans_stmt.ids @ cast_ids;
      instrs = res_trans_stmt.instrs @ cast_inst;
      exps = [cast_exp] }

  (* function used in the computation for both Member_Expr and ObjCIVarRefExpr *)
  and do_memb_ivar_ref_exp trans_state expr_info stmt_info stmt_list decl_ref  =
    let exp_stmt = extract_stmt_from_singleton stmt_list
        "WARNING: in MemberExpr there must be only one stmt defining its expression.\n" in
    let result_trans_exp_stmt = exec_with_lvalue_as_reference instruction trans_state exp_stmt in
    decl_ref_trans trans_state result_trans_exp_stmt stmt_info expr_info decl_ref

  and objCIvarRefExpr_trans trans_state stmt_info expr_info stmt_list obj_c_ivar_ref_expr_info =
    let decl_ref = obj_c_ivar_ref_expr_info.Clang_ast_t.ovrei_decl_ref in
    CFrontend_errors.check_for_ivar_errors trans_state.context stmt_info obj_c_ivar_ref_expr_info;
    do_memb_ivar_ref_exp trans_state expr_info stmt_info stmt_list decl_ref

  and memberExpr_trans trans_state stmt_info expr_info stmt_list member_expr_info =
    let decl_ref = member_expr_info.Clang_ast_t.mei_decl_ref in
    do_memb_ivar_ref_exp trans_state expr_info stmt_info stmt_list decl_ref

  and unaryOperator_trans trans_state stmt_info expr_info stmt_list unary_operator_info =
    let context = trans_state.context in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
    let stmt = extract_stmt_from_singleton stmt_list
        "WARNING: We expect only one element in stmt list defining the operand in UnaryOperator. NEED FIXING\n" in
    let trans_state' = { trans_state_pri with succ_nodes = [] } in
    let res_trans_stmt = instruction trans_state' stmt in
    (* Assumption: the operand does not create a cfg node*)
    let (sil_e', _) = extract_exp_from_list res_trans_stmt.exps "\nWARNING: Missing operand in unary operator. NEED FIXING.\n" in
    let ret_typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv expr_info.Clang_ast_t.ei_type_ptr in
    let ids_op, exp_op, instr_op =
      CArithmetic_trans.unary_operation_instruction unary_operator_info sil_e' ret_typ sil_loc in
    let unary_op_res_trans = { empty_res_trans with ids = ids_op; instrs = instr_op } in
    let all_res_trans = [ res_trans_stmt; unary_op_res_trans ] in
    let nname = "UnaryOperator" in
    let res_trans_to_parent = PriorityNode.compute_results_to_parent trans_state_pri sil_loc nname
        stmt_info all_res_trans in
    { res_trans_to_parent with exps = [(exp_op, ret_typ)] }

  and returnStmt_trans trans_state stmt_info stmt_list =
    let context = trans_state.context in
    let succ_nodes = trans_state.succ_nodes in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
    let mk_ret_node ids instrs =
      let ret_node = create_node (Cfg.Node.Stmt_node "Return Stmt") ids instrs sil_loc context in
      Cfg.Node.set_succs_exn ret_node [(Cfg.Procdesc.get_exit_node context.CContext.procdesc)] [];
      ret_node in
    let trans_result = (match stmt_list with
        | [stmt] -> (* return exp; *)
            let trans_state' = { trans_state_pri with succ_nodes = [] } in
            let res_trans_stmt = exec_with_self_exception instruction trans_state' stmt in
            let (sil_expr, sil_typ) = extract_exp_from_list res_trans_stmt.exps
                "WARNING: There should be only one return expression.\n" in
            let ret_var = Cfg.Procdesc.get_ret_var context.CContext.procdesc in
            let ret_type = Cfg.Procdesc.get_ret_type context.CContext.procdesc in
            let ret_instr = Sil.Set (Sil.Lvar ret_var, ret_type, sil_expr, sil_loc) in
            let autorelease_ids, autorelease_instrs = add_autorelease_call context sil_expr ret_type sil_loc in
            let instrs = res_trans_stmt.instrs @ [ret_instr] @ autorelease_instrs in
            let ids = res_trans_stmt.ids@autorelease_ids in
            let ret_node = mk_ret_node ids instrs in
            IList.iter (fun n -> Cfg.Node.set_succs_exn n [ret_node] []) res_trans_stmt.leaf_nodes;
            let root_nodes_to_parent =
              if IList.length res_trans_stmt.root_nodes >0 then res_trans_stmt.root_nodes else [ret_node] in
            { empty_res_trans with root_nodes = root_nodes_to_parent; leaf_nodes = [ret_node]}
        | [] -> (* return; *)
            let ret_node = mk_ret_node [] [] in
            { empty_res_trans with root_nodes = [ret_node]; leaf_nodes = [ret_node]}
        | _ -> Printing.log_out
                 "\nWARNING: Missing translation of Return Expression. Return Statement ignored. Need fixing!\n";
            { empty_res_trans with root_nodes = succ_nodes }) in (* We expect a return with only one expression *)
    trans_result

  (* We analyze the content of the expr. We treat ExprWithCleanups as a wrapper. *)
  (*  It may be that later on (when we treat ARC) some info can be taken from it. *)
  (* For ParenExpression we translate its body composed by the stmt_list.  *)
  (* In paren expression there should be only one stmt that defines the  expression  *)
  and parenExpr_trans trans_state stmt_info stmt_list =
    let stmt = extract_stmt_from_singleton stmt_list
        "WARNING: In ParenExpression there should be only one stmt.\n" in
    instruction trans_state stmt

  and objCBoxedExpr_trans trans_state info sel stmt_info stmts =
    let typ = CTypes_decl.class_from_pointer_type trans_state.context.CContext.tenv info.Clang_ast_t.ei_type_ptr in
    let obj_c_message_expr_info = Ast_expressions.make_obj_c_message_expr_info_class sel typ None in
    let message_stmt = Clang_ast_t.ObjCMessageExpr (stmt_info, stmts, info, obj_c_message_expr_info) in
    instruction trans_state message_stmt

  and objCArrayLiteral_trans trans_state info stmt_info stmts =
    let typ = CTypes_decl.class_from_pointer_type trans_state.context.CContext.tenv info.Clang_ast_t.ei_type_ptr in
    let meth = CFrontend_config.array_with_objects_count_m in
    let obj_c_mes_expr_info = Ast_expressions.make_obj_c_message_expr_info_class meth typ None in
    let stmts = stmts @ [Ast_expressions.create_nil stmt_info] in
    let message_stmt = Clang_ast_t.ObjCMessageExpr (stmt_info, stmts, info, obj_c_mes_expr_info) in
    instruction trans_state message_stmt

  and objCDictionaryLiteral_trans trans_state info stmt_info stmts =
    let typ = CTypes_decl.class_from_pointer_type trans_state.context.CContext.tenv info.Clang_ast_t.ei_type_ptr in
    let dictionary_literal_pname = SymExec.ModelBuiltins.__objc_dictionary_literal in
    let dictionary_literal_s = Procname.c_get_method dictionary_literal_pname in
    let obj_c_message_expr_info =
      Ast_expressions.make_obj_c_message_expr_info_class dictionary_literal_s typ None in
    let stmts = General_utils.swap_elements_list stmts in
    let stmts = stmts @ [Ast_expressions.create_nil stmt_info] in
    let message_stmt = Clang_ast_t.ObjCMessageExpr (stmt_info, stmts, info, obj_c_message_expr_info) in
    instruction trans_state message_stmt

  and objCStringLiteral_trans trans_state stmt_info stmts info =
    let stmts = [Ast_expressions.create_implicit_cast_expr stmt_info stmts
                   Ast_expressions.create_char_star_type `ArrayToPointerDecay] in
    let typ = CTypes_decl.class_from_pointer_type trans_state.context.CContext.tenv info.Clang_ast_t.ei_type_ptr in
    let meth = CFrontend_config.string_with_utf8_m in
    let obj_c_mess_expr_info = Ast_expressions.make_obj_c_message_expr_info_class meth typ None in
    let message_stmt = Clang_ast_t.ObjCMessageExpr (stmt_info, stmts, info, obj_c_mess_expr_info) in
    instruction trans_state message_stmt

  (** When objects are autoreleased, they get added a flag AUTORELEASE. All these objects will be
      ignored when checking for memory leaks. When the end of the block autoreleasepool is reached,
      then those objects are released and the autorelease flag is removed. *)
  and objcAutoreleasePool_trans trans_state stmt_info stmts =
    let sil_loc = CLocation.get_sil_location stmt_info trans_state.context in
    let fname = SymExec.ModelBuiltins.__objc_release_autorelease_pool in
    let ret_id = Ident.create_fresh Ident.knormal in
    let autorelease_pool_vars = CVar_decl.compute_autorelease_pool_vars trans_state.context stmts in
    let stmt_call = Sil.Call([ret_id], (Sil.Const (Sil.Cfun fname)), autorelease_pool_vars, sil_loc, Sil.cf_default) in
    let node_kind = Cfg.Node.Stmt_node ("Release the autorelease pool") in
    let call_node = create_node node_kind ([ret_id]) ([stmt_call]) sil_loc trans_state.context in
    Cfg.Node.set_succs_exn call_node trans_state.succ_nodes [];
    let trans_state'={ trans_state with continuation = None; succ_nodes =[call_node] } in
    instructions trans_state' stmts

  (* Assumption: stmt_list contains 2 items, the first can be ObjCMessageExpr or ParenExpr *)
  (* We ignore this item since we don't deal with the concurrency problem yet *)
  (* For the same reason we also ignore the stmt_info that is related with the ObjCAtSynchronizedStmt construct *)
  (* Finally we recursively work on the CompoundStmt, the second item of stmt_list *)
  and objCAtSynchronizedStmt_trans trans_state stmt_info stmt_list =
    (match stmt_list with
     | [_; compound_stmt] -> instruction trans_state compound_stmt
     | _ -> assert false)

  and blockExpr_trans trans_state stmt_info expr_info decl =
    let context = trans_state.context in
    let procname = Cfg.Procdesc.get_proc_name context.CContext.procdesc in
    let loc =
      (match stmt_info.Clang_ast_t.si_source_range with (l1, l2) ->
        CLocation.clang_to_sil_location l1 (Some context.CContext.procdesc)) in
    (* Given a captured var, return the instruction to assign it to a temp *)
    let assign_captured_var (cvar, typ) =
      let id = Ident.create_fresh Ident.knormal in
      let instr = Sil.Letderef (id, (Sil.Lvar cvar), typ, loc) in
      (id, instr) in
    match decl with
    | Clang_ast_t.BlockDecl (decl_info, block_decl_info) ->
        let open CContext in
        let type_ptr = expr_info.Clang_ast_t.ei_type_ptr in
        let block_pname = CFrontend_utils.General_utils.mk_fresh_block_procname procname in
        let typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
        (* We need to set the explicit dependency between the newly created block and the *)
        (* defining procedure. We add an edge in the call graph.*)
        Cg.add_edge context.cg procname block_pname;
        let captured_block_vars = block_decl_info.Clang_ast_t.bdi_captured_variables in
        let captured_vars = CVar_decl.captured_vars_from_block_info context captured_block_vars in
        CFrontend_errors.check_for_captured_vars context stmt_info captured_vars;
        let ids_instrs = IList.map assign_captured_var captured_vars in
        let ids, instrs = IList.split ids_instrs in
        let block_data = (context, type_ptr, block_pname, captured_vars) in
        M.function_decl context.tenv context.cfg context.cg decl (Some block_data);
        Cfg.set_procname_priority context.cfg block_pname;
        let captured_exps = IList.map (fun id -> Sil.Var id) ids in
        let tu = Sil.Ctuple ((Sil.Const (Sil.Cfun block_pname)) :: captured_exps) in
        let block_name = Procname.to_string block_pname in
        let static_vars = CContext.static_vars_for_block context block_pname in
        let captured_static_vars = captured_vars @ static_vars in
        let alloc_block_instr, ids_block =
          allocate_block trans_state block_name captured_static_vars loc in
        { empty_res_trans with ids = ids_block @ ids; instrs = alloc_block_instr @ instrs; exps = [(Sil.Const tu, typ)]}
    | _ -> assert false

  and cxxNewExpr_trans trans_state stmt_info expr_info =
    let context = trans_state.context in
    let typ = CTypes_decl.get_type_from_expr_info expr_info context.CContext.tenv in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
    cpp_new_trans trans_state_pri sil_loc stmt_info typ
  (* TODOs 7912220 - no usable information in json as of right now *)
  (* 1. Handle __new_array *)
  (* 2. Handle initialization values *)

  and cxxDeleteExpr_trans trans_state stmt_info stmt_list expr_info delete_expr_info =
    let context = trans_state.context in
    let sil_loc = CLocation.get_sil_location stmt_info context in
    let fname = SymExec.ModelBuiltins.__delete in
    let param = match stmt_list with [p] -> p | _ -> assert false in
    let trans_state_pri = PriorityNode.try_claim_priority_node trans_state stmt_info in
    let trans_state_param = { trans_state_pri with succ_nodes = [] } in
    let result_trans_param = exec_with_self_exception instruction trans_state_param param in
    let exp = extract_exp_from_list result_trans_param.exps
        "WARNING: There should be one expression to delete. \n" in
    let deleted_type = delete_expr_info.Clang_ast_t.xdei_destroyed_type in
    (* create stmt_info with new pointer so that destructor call doesn't create a node *)
    let destruct_stmt_info = { stmt_info with
                               Clang_ast_t.si_pointer = Ast_utils.get_fresh_pointer () } in
    (* use empty_res_trans to avoid ending up with same instruction twice *)
    (* otherwise it would happen due to structutre of all_res_trans *)
    let this_res_trans_destruct = { empty_res_trans with exps = result_trans_param.exps } in
    let destruct_res_trans = cxx_destructor_call_trans trans_state_pri destruct_stmt_info
        this_res_trans_destruct deleted_type in
    (* function is void *)
    let call_instr = Sil.Call ([], (Sil.Const (Sil.Cfun fname)), [exp], sil_loc, Sil.cf_default) in
    let call_res_trans = { empty_res_trans with instrs = [call_instr] } in
    let all_res_trans = [ result_trans_param; destruct_res_trans; call_res_trans] in
    let res_trans = PriorityNode.compute_results_to_parent trans_state_pri sil_loc
        "Call delete" stmt_info all_res_trans in
    { res_trans with exps = [] }

  and materializeTemporaryExpr_trans trans_state stmt_info stmt_list expr_info =
    let context = trans_state.context in
    let procdesc = context.CContext.procdesc in
    let procname = Cfg.Procdesc.get_proc_name procdesc in
    let temp_exp = match stmt_list with [p] -> p | _ -> assert false in
    (* use id to create unique variable name within a function *)
    let id = Ident.create_fresh Ident.knormal in
    let pvar_mangled = Mangled.from_string ("SIL_materialize_temp__" ^ (Ident.to_string id)) in
    let pvar = Sil.mk_pvar pvar_mangled procname in
    let type_ptr = expr_info.Clang_ast_t.ei_type_ptr in
    let typ = CTypes_decl.type_ptr_to_sil_type context.CContext.tenv type_ptr in
    let typ_ptr = Sil.Tptr (typ, Sil.Pk_pointer) in
    let var_res_trans = { empty_res_trans with exps = [(Sil.Lvar pvar, typ_ptr)] } in
    Cfg.Procdesc.append_locals procdesc [(Sil.pvar_get_name pvar, typ)];
    let res_trans = init_expr_trans trans_state var_res_trans stmt_info (Some temp_exp) in
    { res_trans with exps = [(Sil.Lvar pvar, typ)] }

  (* Translates a clang instruction into SIL instructions. It takes a       *)
  (* a trans_state containing current info on the translation and it returns *)
  (* a result_state.*)
  and instruction trans_state instr =
    let stmt_kind = Clang_ast_proj.get_stmt_kind_string instr in
    let stmt_info, _ = Clang_ast_proj.get_stmt_tuple instr in
    let stmt_pointer = stmt_info.Clang_ast_t.si_pointer in
    Printing.log_out "\nPassing from %s '%d' \n" stmt_kind stmt_pointer;
    let open Clang_ast_t in
    match instr with
    | GotoStmt(stmt_info, _, { Clang_ast_t.gsi_label = label_name; _ }) ->
        gotoStmt_trans trans_state stmt_info label_name

    | LabelStmt(stmt_info, stmt_list, label_name) ->
        labelStmt_trans trans_state stmt_info stmt_list label_name

    | ArraySubscriptExpr(stmt_info, stmt_list, expr_info) ->
        arraySubscriptExpr_trans trans_state stmt_info expr_info stmt_list

    | BinaryOperator(stmt_info, stmt_list, expr_info, binary_operator_info) ->
        binaryOperator_trans trans_state binary_operator_info stmt_info expr_info stmt_list

    | CallExpr(stmt_info, stmt_list, ei) ->
        (match is_dispatch_function stmt_list with
         | Some block_arg_pos ->
             dispatch_function_trans trans_state stmt_info stmt_list ei block_arg_pos
         | None ->
             callExpr_trans trans_state stmt_info stmt_list ei)

    | CXXMemberCallExpr(stmt_info, stmt_list, ei) ->
        cxxMemberCallExpr_trans trans_state stmt_info stmt_list ei

    | CXXOperatorCallExpr(stmt_info, stmt_list, ei) ->
        callExpr_trans trans_state stmt_info stmt_list ei

    | ObjCMessageExpr(stmt_info, stmt_list, expr_info, obj_c_message_expr_info) ->
        if is_block_enumerate_function obj_c_message_expr_info then
          block_enumeration_trans trans_state stmt_info stmt_list expr_info
        else
          objCMessageExpr_trans trans_state stmt_info obj_c_message_expr_info stmt_list expr_info

    | CompoundStmt (stmt_info, stmt_list) ->
        (* No node for this statement. We just collect its statement list*)
        compoundStmt_trans trans_state stmt_info stmt_list

    | ConditionalOperator(stmt_info, stmt_list, expr_info) ->
        (* Ternary operator "cond ? exp1 : exp2" *)
        conditionalOperator_trans trans_state stmt_info stmt_list expr_info

    | IfStmt(stmt_info, stmt_list) ->
        ifStmt_trans trans_state stmt_info stmt_list

    | SwitchStmt (stmt_info, switch_stmt_list) ->
        switchStmt_trans trans_state stmt_info switch_stmt_list

    | CaseStmt (stmt_info, stmt_list) ->
        Printing.log_out "FATAL: Passing from CaseStmt outside of SwitchStmt, terminating.\n"; assert false

    | StmtExpr(stmt_info, stmt_list, expr_info) ->
        stmtExpr_trans trans_state stmt_info stmt_list expr_info

    | ForStmt(stmt_info, [init; decl_stmt; cond; incr; body]) ->
        (* Note: we ignore null_stmt at the moment.*)
        forStmt_trans trans_state init decl_stmt cond incr body stmt_info

    | WhileStmt(stmt_info, [decl_stmt; cond; body]) ->
        whileStmt_trans trans_state decl_stmt cond body stmt_info

    | DoStmt(stmt_info, [body; cond]) ->
        doStmt_trans trans_state stmt_info cond body

    | ObjCForCollectionStmt(stmt_info, [item; items; body]) ->
        objCForCollectionStmt_trans trans_state item items body stmt_info

    | NullStmt(stmt_info, stmt_list) ->
        nullStmt_trans trans_state.succ_nodes stmt_info

    | CompoundAssignOperator(stmt_info, stmt_list, expr_info, binary_operator_info, caoi) ->
        binaryOperator_trans trans_state binary_operator_info stmt_info expr_info stmt_list

    | DeclStmt(stmt_info, stmt_list, decl_list) ->
        declStmt_trans trans_state decl_list stmt_info

    | DeclRefExpr(stmt_info, stmt_list, expr_info, decl_ref_expr_info) as d ->
        declRefExpr_trans trans_state stmt_info expr_info decl_ref_expr_info d

    | ObjCPropertyRefExpr(stmt_info, stmt_list, expr_info, property_ref_expr_info) ->
        objCPropertyRefExpr_trans trans_state stmt_info stmt_list

    | CXXThisExpr(stmt_info, _, expr_info) -> cxxThisExpr_trans trans_state stmt_info expr_info

    | OpaqueValueExpr(stmt_info, stmt_list, expr_info, opaque_value_expr_info) ->
        opaqueValueExpr_trans trans_state stmt_info opaque_value_expr_info

    | PseudoObjectExpr(stmt_info, stmt_list, expr_info) ->
        pseudoObjectExpr_trans trans_state stmt_info stmt_list

    | UnaryExprOrTypeTraitExpr(stmt_info, stmt_list, expr_info, ei) ->
        unaryExprOrTypeTraitExpr_trans trans_state stmt_info expr_info ei

    | ObjCBridgedCastExpr(stmt_info, stmt_list, expr_info, cast_kind, _) ->
        cast_exprs_trans trans_state stmt_info stmt_list expr_info cast_kind true
    | ImplicitCastExpr(stmt_info, stmt_list, expr_info, cast_kind)
    | CStyleCastExpr(stmt_info, stmt_list, expr_info, cast_kind, _)
    | CXXStaticCastExpr(stmt_info, stmt_list, expr_info, cast_kind, _, _) ->
        cast_exprs_trans trans_state stmt_info stmt_list expr_info cast_kind false

    | IntegerLiteral(stmt_info, _, expr_info, integer_literal_info) ->
        integerLiteral_trans trans_state stmt_info expr_info integer_literal_info

    | StringLiteral(stmt_info, stmt_list, expr_info, str) ->
        stringLiteral_trans trans_state stmt_info expr_info str

    | GNUNullExpr(stmt_info, stmt_list, expr_info) ->
        gNUNullExpr_trans trans_state stmt_info expr_info

    | CXXNullPtrLiteralExpr(stmt_info, stmt_list, expr_info) ->
        nullPtrExpr_trans trans_state stmt_info expr_info

    | ObjCSelectorExpr(stmt_info, stmt_list, expr_info, selector) ->
        objCSelectorExpr_trans trans_state stmt_info expr_info selector

    | ObjCEncodeExpr(stmt_info, stmt_list, expr_info, type_ptr) ->
        objCEncodeExpr_trans trans_state stmt_info expr_info type_ptr

    | ObjCProtocolExpr(stmt_info, stmt_list, expr_info, decl_ref) ->
        objCProtocolExpr_trans trans_state stmt_info expr_info decl_ref

    | ObjCIvarRefExpr(stmt_info, stmt_list, expr_info, obj_c_ivar_ref_expr_info) ->
        objCIvarRefExpr_trans trans_state stmt_info expr_info stmt_list obj_c_ivar_ref_expr_info

    | MemberExpr(stmt_info, stmt_list, expr_info, member_expr_info) ->
        memberExpr_trans trans_state stmt_info expr_info stmt_list member_expr_info

    | UnaryOperator(stmt_info, stmt_list, expr_info, unary_operator_info) ->
        if is_logical_negation_of_int trans_state.context.CContext.tenv expr_info unary_operator_info then
          let conditional = Ast_expressions.trans_negation_with_conditional stmt_info expr_info stmt_list in
          instruction trans_state conditional
        else
          unaryOperator_trans trans_state stmt_info expr_info stmt_list unary_operator_info

    | ReturnStmt (stmt_info, stmt_list) ->
        returnStmt_trans trans_state stmt_info stmt_list

    (* We analyze the content of the expr. We treat ExprWithCleanups as a wrapper. *)
    (*  It may be that later on (when we treat ARC) some info can be taken from it. *)
    | ExprWithCleanups(stmt_info, stmt_list, expr_info, _)
    | ParenExpr(stmt_info, stmt_list, expr_info) ->
        parenExpr_trans trans_state stmt_info stmt_list

    | ObjCBoolLiteralExpr (stmt_info, stmts, expr_info, n)
    | CharacterLiteral (stmt_info, stmts, expr_info, n)
    | CXXBoolLiteralExpr (stmt_info, stmts, expr_info, n) ->
        characterLiteral_trans trans_state stmt_info expr_info n

    | FloatingLiteral (stmt_info, stmts, expr_info, float_string) ->
        floatingLiteral_trans trans_state stmt_info expr_info float_string

    | ObjCBoxedExpr (stmt_info, stmts, info, sel) ->
        objCBoxedExpr_trans trans_state info sel stmt_info stmts

    | ObjCArrayLiteral (stmt_info, stmts, info) ->
        objCArrayLiteral_trans trans_state info stmt_info stmts

    | ObjCDictionaryLiteral (stmt_info, stmts, info) ->
        objCDictionaryLiteral_trans trans_state info stmt_info stmts

    | ObjCStringLiteral(stmt_info, stmts, info) ->
        objCStringLiteral_trans trans_state stmt_info stmts info

    | BreakStmt(stmt_info, lstmt) -> breakStmt_trans trans_state

    | ContinueStmt(stmt_infr, lstmt) -> continueStmt_trans trans_state

    | ObjCAtSynchronizedStmt(stmt_info, stmt_list) ->
        objCAtSynchronizedStmt_trans trans_state stmt_info stmt_list

    | ObjCIndirectCopyRestoreExpr (stmt_info, stmt_list, _) ->
        instructions trans_state stmt_list

    | BlockExpr(stmt_info, _ , expr_info, decl) ->
        blockExpr_trans trans_state stmt_info expr_info decl

    | ObjCAutoreleasePoolStmt (stmt_info, stmts) ->
        objcAutoreleasePool_trans trans_state stmt_info stmts

    | ObjCAtTryStmt (stmt_info, stmts) ->
        compoundStmt_trans trans_state stmt_info stmts

    | ObjCAtThrowStmt (stmt_info, stmts) ->
        returnStmt_trans trans_state stmt_info stmts

    | ObjCAtFinallyStmt (stmt_info, stmts) ->
        compoundStmt_trans trans_state stmt_info stmts

    | ObjCAtCatchStmt (stmt_info, stmts, obj_c_message_expr_kind) ->
        compoundStmt_trans trans_state stmt_info []

    | PredefinedExpr (stmt_info, stmts, expr_info, predefined_expr_type) ->
        stringLiteral_trans trans_state stmt_info expr_info ""

    | BinaryConditionalOperator (stmt_info, stmts, expr_info) ->
        (match stmts with
         | [stmt1; ostmt1; ostmt2; stmt2] when contains_opaque_value_expr ostmt1 && contains_opaque_value_expr ostmt2 ->
             conditionalOperator_trans trans_state stmt_info [stmt1; stmt1; stmt2] expr_info
         | _ -> Printing.log_stats
                  "BinaryConditionalOperator not translated %s @."
                  (Ast_utils.string_of_stmt instr);
             assert false)
    | CXXNewExpr (stmt_info, stmt_list, expr_info, _) ->
        cxxNewExpr_trans trans_state stmt_info expr_info
    | CXXDeleteExpr (stmt_info, stmt_list, expr_info, delete_expr_info) ->
        cxxDeleteExpr_trans trans_state stmt_info stmt_list expr_info delete_expr_info
    | MaterializeTemporaryExpr (stmt_info, stmt_list, expr_info, _) ->
        materializeTemporaryExpr_trans trans_state stmt_info stmt_list expr_info
    | s -> (Printing.log_stats
              "\n!!!!WARNING: found statement %s. \nACTION REQUIRED: Translation need to be defined. Statement ignored.... \n"
              (Ast_utils.string_of_stmt s);
            assert false)

  (** Given a translation state and list of translation functions it executes translation *)
  and exec_trans_instrs trans_state trans_stmt_fun_list =
    match trans_stmt_fun_list with
    | [] -> { empty_res_trans with root_nodes = trans_state.succ_nodes }
    | trans_stmt_fun :: trans_stmt_fun_list' ->
        let res_trans_s = trans_stmt_fun trans_state in
        let trans_state' =
          if res_trans_s.root_nodes <> []
          then { trans_state with succ_nodes = res_trans_s.root_nodes }
          else trans_state in
        let res_trans_tail = exec_trans_instrs trans_state' trans_stmt_fun_list' in
        { root_nodes = res_trans_tail.root_nodes;
          leaf_nodes = [];
          ids = res_trans_s.ids @ res_trans_tail.ids;
          instrs = res_trans_s.instrs @ res_trans_tail.instrs;
          exps = res_trans_s.exps @ res_trans_tail.exps }

  and get_clang_stmt_trans stmt_list =
    let instruction' = fun stmt -> fun trans_state -> instruction trans_state stmt in
    IList.map instruction' stmt_list

  and get_custom_stmt_trans custom_stmts =
    (* TODO write translate function for cxx constructor exprs *)
    let do_one_stmt stmt = match stmt with
      | `ClangStmt stmt -> get_clang_stmt_trans [stmt]
      | `CXXConstructorInit instr -> [] in
    IList.flatten (IList.map do_one_stmt custom_stmts)

  (** Given a translation state, this function translates a list of clang statements. *)
  and instructions trans_state stmt_list =
    exec_trans_instrs trans_state (get_clang_stmt_trans stmt_list)

  and expression_trans context stmt warning =
    let trans_state = {
      context = context;
      succ_nodes = [];
      continuation = None;
      priority = Free;
    } in
    let res_trans_stmt = instruction trans_state stmt in
    fst (CTrans_utils.extract_exp_from_list res_trans_stmt.exps warning)

  let instructions_trans context clang_stmt_list extra_instrs exit_node =
    let trans_state = {
      context = context;
      succ_nodes = [exit_node];
      continuation = None;
      priority = Free;
    } in
    let clang_ast_trans = get_clang_stmt_trans clang_stmt_list in
    let extra_stmt_trans = get_custom_stmt_trans extra_instrs in
    let res_trans = exec_trans_instrs trans_state (clang_ast_trans @ extra_stmt_trans) in
    res_trans.root_nodes

end