+let get_trans_aux a tag states =
+ StateSet.fold (fun q acc0 ->
+ try
+ let trs = Hashtbl.find a.transitions q in
+ List.fold_left (fun acc1 (labs, phi) ->
+ if QNameSet.mem tag labs then TransList.cons (Transition.make (q, labs, phi)) acc1 else acc1) acc0 trs
+ with Not_found -> acc0
+ ) states TransList.nil
+
+
+let get_trans a tag states =
+ let trs =
+ Cache.N2.find a.cache2
+ (tag.QName.id :> int) (states.StateSet.id :> int)
+ in
+ if trs == dummy2 then
+ let trs = get_trans_aux a tag states in
+ (Cache.N2.add
+ a.cache2
+ (tag.QName.id :> int)
+ (states.StateSet.id :> int) trs; trs)
+ else trs
+
+let simplify_atom atom pos q { Config.node=config; _ } =
+ if (pos && StateSet.mem q config.sat)
+ || ((not pos) && StateSet.mem q config.unsat) then SFormula.true_
+ else if (pos && StateSet.mem q config.unsat)
+ || ((not pos) && StateSet.mem q config.sat) then SFormula.false_
+ else atom
+
+let eval_form phi fcs nss ps ss summary =
+ let rec loop phi =
+ begin match SFormula.expr phi with
+ Formula.True | Formula.False -> phi
+ | Formula.Atom a ->
+ let p, b, q = Atom.node a in begin
+ match p with
+ | First_child -> simplify_atom phi b q fcs
+ | Next_sibling -> simplify_atom phi b q nss
+ | Parent | Previous_sibling -> simplify_atom phi b q ps
+ | Stay -> simplify_atom phi b q ss
+ | Is_first_child -> SFormula.of_bool (b == (is_left summary))
+ | Is_next_sibling -> SFormula.of_bool (b == (is_right summary))
+ | Is k -> SFormula.of_bool (b == (k == (kind summary)))
+ | Has_first_child -> SFormula.of_bool (b == (has_left summary))
+ | Has_next_sibling -> SFormula.of_bool (b == (has_right summary))
+ end
+ | Formula.And(phi1, phi2) -> SFormula.and_ (loop phi1) (loop phi2)
+ | Formula.Or (phi1, phi2) -> SFormula.or_ (loop phi1) (loop phi2)
+ end
+ in
+ loop phi
+
+
+
+let eval_trans auto fcs nss ps ss =
+ let fcsid = (fcs.Config.id :> int) in
+ let nssid = (nss.Config.id :> int) in
+ let psid = (ps.Config.id :> int) in
+ let rec loop old_config =
+ let oid = (old_config.Config.id :> int) in
+ let res =
+ let res = Cache.N4.find auto.cache4 oid fcsid nssid psid in
+ if res != dummy_config then res
+ else
+ let { sat = old_sat;
+ unsat = old_unsat;
+ todo = old_todo;
+ summary = old_summary } = old_config.Config.node
+ in
+ let sat, unsat, removed, kept, todo =
+ TransList.fold
+ (fun trs acc ->
+ let q, lab, phi = Transition.node trs in
+ let a_sat, a_unsat, a_rem, a_kept, a_todo = acc in
+ if StateSet.mem q a_sat || StateSet.mem q a_unsat then acc else
+ let new_phi =
+ eval_form phi fcs nss ps old_config old_summary
+ in
+ if SFormula.is_true new_phi then
+ StateSet.add q a_sat, a_unsat, StateSet.add q a_rem, a_kept, a_todo
+ else if SFormula.is_false new_phi then
+ a_sat, StateSet.add q a_unsat, StateSet.add q a_rem, a_kept, a_todo
+ else
+ let new_tr = Transition.make (q, lab, new_phi) in
+ (a_sat, a_unsat, a_rem, StateSet.add q a_kept, (TransList.cons new_tr a_todo))
+ ) old_todo (old_sat, old_unsat, StateSet.empty, StateSet.empty, TransList.nil)
+ in
+ (* States that have been removed from the todo list and not kept are now
+ unsatisfiable *)
+ let unsat = StateSet.union unsat (StateSet.diff removed kept) in
+ (* States that were found once to be satisfiable remain so *)
+ let unsat = StateSet.diff unsat sat in
+ let new_config = Config.make { old_config.Config.node with sat; unsat; todo; } in
+ Cache.N4.add auto.cache4 oid fcsid nssid psid new_config;
+ new_config
+ in
+ if res == old_config then res else loop res
+ in
+ loop ss
+
+(*
+ [add_trans a q labels f] adds a transition [(q,labels) -> f] to the
+ automaton [a] but ensures that transitions remains pairwise disjoint
+*)