1 (***********************************************************************)
5 (* Kim Nguyen, LRI UMR8623 *)
6 (* Université Paris-Sud & CNRS *)
8 (* Copyright 2010-2013 Université Paris-Sud and Centre National de la *)
9 (* Recherche Scientifique. All rights reserved. This file is *)
10 (* distributed under the terms of the GNU Lesser General Public *)
11 (* License, with the special exception on linking described in file *)
14 (***********************************************************************)
17 Time-stamp: <Last modified on 2013-03-05 16:31:57 CET by Kim Nguyen>
24 type move = [ `Left | `Right | `Up1 | `Up2 | `Epsilon ]
25 type state_ctx = { mutable left : StateSet.t;
26 mutable right : StateSet.t;
27 mutable up1 : StateSet.t;
28 mutable up2 : StateSet.t;
29 mutable epsilon : StateSet.t}
31 type pred_ = move * bool * State.t
32 let make_ctx a b c d e =
33 { left = a; right = b; up1 = c; up2 = d; epsilon = e }
35 let print_ctx fmt c = fprintf fmt "{ left : %a; right : %a; up1: %a ; up2 : %a; epsilon : %a }"
36 StateSet.print c.left StateSet.print c.right StateSet.print c.up1 StateSet.print c.up2
37 StateSet.print c.epsilon
39 module Move : (Formula.PREDICATE with type data = pred_ and type ctx = state_ctx ) =
44 type t = move * bool * State.t
45 let equal n1 n2 = n1 = n2
46 let hash n = Hashtbl.hash n
52 include Hcons.Make(Node)
53 let _pr_buff = Buffer.create 10
54 let _str_fmt = formatter_of_buffer _pr_buff
55 let _flush_str_fmt () = pp_print_flush _str_fmt ();
56 let s = Buffer.contents _pr_buff in
57 Buffer.clear _pr_buff; s
60 let _ = _flush_str_fmt () in
62 let m, b, s = a.node in
65 | `Left -> Pretty.down_arrow, Pretty.subscript 1
66 | `Right -> Pretty.down_arrow, Pretty.subscript 2
67 | `Epsilon -> Pretty.epsilon, ""
68 | `Up1 -> Pretty.up_arrow, Pretty.subscript 1
69 | `Up2 -> Pretty.up_arrow, Pretty.subscript 2
71 fprintf _str_fmt "%s%s" dir num;
72 State.print _str_fmt s;
73 let str = _flush_str_fmt () in
74 if b then fprintf ppf "%s" str
75 else Pretty.pp_overline ppf str
78 let l, b, s = p.node in
80 exception NegativeAtom of (move*State.t)
82 let l, b, s = p.node in
83 if not b then raise (NegativeAtom(l,s));
90 | `Epsilon -> ctx.epsilon
94 module SFormula = Formula.Make(Move)
97 mutable states : StateSet.t;
98 mutable top_states : StateSet.t;
99 mutable bottom_states: StateSet.t;
100 mutable selection_states: StateSet.t;
101 transitions: (State.t, (QNameSet.t*SFormula.t) list) Hashtbl.t;
104 let next = Uid.make_maker ()
106 let create () = { id = next ();
107 states = StateSet.empty;
108 top_states = StateSet.empty;
109 bottom_states = StateSet.empty;
110 selection_states = StateSet.empty;
111 transitions = Hashtbl.create 17;
115 let get_trans a states tag =
116 StateSet.fold (fun q acc0 ->
118 let trs = Hashtbl.find a.transitions q in
119 List.fold_left (fun acc1 (labs, phi) ->
120 if QNameSet.mem tag labs then (q,phi)::acc1 else acc1) acc0 trs
121 with Not_found -> acc0
125 [add_trans a q labels f] adds a transition [(q,labels) -> f] to the
126 automaton [a] but ensures that transitions remains pairwise disjoint
129 let add_trans a q s f =
130 let trs = try Hashtbl.find a.transitions q with Not_found -> [] in
132 List.fold_left (fun (acup, atrs) (labs, phi) ->
133 let lab1 = QNameSet.inter labs s in
134 let lab2 = QNameSet.diff labs s in
136 if QNameSet.is_empty lab1 then []
137 else [ (lab1, SFormula.or_ phi f) ]
140 if QNameSet.is_empty lab2 then []
141 else [ (lab2, SFormula.or_ phi f) ]
143 (QNameSet.union acup labs, tr1@ tr2 @ atrs)
144 ) (QNameSet.empty, []) trs
146 let rem = QNameSet.diff s cup in
147 let ntrs = if QNameSet.is_empty rem then ntrs
148 else (rem, f) :: ntrs
150 Hashtbl.replace a.transitions q ntrs
152 let _pr_buff = Buffer.create 50
153 let _str_fmt = formatter_of_buffer _pr_buff
154 let _flush_str_fmt () = pp_print_flush _str_fmt ();
155 let s = Buffer.contents _pr_buff in
156 Buffer.clear _pr_buff; s
160 "\nInternal UID: %i@\n\
163 Bottom states: %a@\n\
164 Selection states: %a@\n\
165 Alternating transitions:@\n"
167 StateSet.print a.states
168 StateSet.print a.top_states
169 StateSet.print a.bottom_states
170 StateSet.print a.selection_states;
173 (fun q t acc -> List.fold_left (fun acc (s , f) -> (q,s,f)::acc) acc t)
177 let sorted_trs = List.stable_sort (fun (q1, s1, _) (q2, s2, _) ->
178 let c = State.compare q1 q2 in - (if c == 0 then QNameSet.compare s1 s2 else c))
181 let _ = _flush_str_fmt () in
182 let strs_strings, max_pre, max_all = List.fold_left (fun (accl, accp, acca) (q, s, f) ->
183 let s1 = State.print _str_fmt q; _flush_str_fmt () in
184 let s2 = QNameSet.print _str_fmt s; _flush_str_fmt () in
185 let s3 = SFormula.print _str_fmt f; _flush_str_fmt () in
186 let pre = Pretty.length s1 + Pretty.length s2 in
187 let all = Pretty.length s3 in
188 ( (q, s1, s2, s3) :: accl, max accp pre, max acca all)
189 ) ([], 0, 0) sorted_trs
191 let line = Pretty.line (max_all + max_pre + 6) in
192 let prev_q = ref State.dummy in
193 List.iter (fun (q, s1, s2, s3) ->
194 if !prev_q != q && !prev_q != State.dummy then fprintf fmt " %s\n%!" line;
196 fprintf fmt " %s, %s" s1 s2;
197 fprintf fmt "%s" (Pretty.padding (max_pre - Pretty.length s1 - Pretty.length s2));
198 fprintf fmt " %s %s@\n%!" Pretty.right_arrow s3;
200 fprintf fmt " %s\n%!" line
203 [complete transitions a] ensures that for each state q
204 and each symbols s in the alphabet, a transition q, s exists.
205 (adding q, s -> F when necessary).
208 let complete_transitions a =
209 StateSet.iter (fun q ->
210 let qtrans = Hashtbl.find a.transitions q in
212 List.fold_left (fun rem (labels, _) ->
213 QNameSet.diff rem labels) QNameSet.any qtrans
216 if QNameSet.is_empty rem then qtrans
218 (rem, SFormula.false_) :: qtrans
220 Hashtbl.replace a.transitions q nqtrans
223 (* [normalize_negations a] removes negative atoms in the formula
224 complementing the sub-automaton in the negative states.
225 [TODO check the meaning of negative upward arrows]
227 let normalize_negations auto =
228 let memo_state = Hashtbl.create 17 in
229 let todo = Queue.create () in
231 match SFormula.expr f with
232 Formula.True | Formula.False -> if b then f else SFormula.not_ f
233 | Formula.Or(f1, f2) -> (if b then SFormula.or_ else SFormula.and_)(flip b f1) (flip b f2)
234 | Formula.And(f1, f2) -> (if b then SFormula.and_ else SFormula.or_)(flip b f1) (flip b f2)
235 | Formula.Atom(a) -> begin
236 let l, b', q = Move.node a in
237 if b == b' then begin
238 (* a appears positively, either no negation or double negation *)
239 if not (Hashtbl.mem memo_state (q,b)) then Queue.add (q,true) todo;
240 SFormula.atom_ (Move.make (l, true, q))
242 (* need to reverse the atom
243 either we have a positive state deep below a negation
244 or we have a negative state in a positive formula
245 b' = sign of the state
246 b = sign of the enclosing formula
250 (* does the inverted state of q exist ? *)
251 Hashtbl.find memo_state (q, false)
254 (* create a new state and add it to the todo queue *)
255 let nq = State.make () in
256 if not (StateSet.mem q auto.bottom_states) then
257 auto.bottom_states <- StateSet.add nq auto.bottom_states;
258 if not (StateSet.mem q auto.top_states) then
259 auto.top_states <- StateSet.add nq auto.top_states;
260 Hashtbl.add memo_state (q, false) nq;
261 Queue.add (q, false) todo; nq
263 SFormula.atom_ (Move.make (l, true, not_q))
267 (* states that are not reachable from a selection stat are not interesting *)
268 StateSet.iter (fun q -> Queue.add (q, true) todo) auto.selection_states;
270 while not (Queue.is_empty todo) do
271 let (q, b) as key = Queue.pop todo in
274 Hashtbl.find memo_state key
277 let nq = if b then q else
278 let nq = State.make () in
279 if not (StateSet.mem q auto.bottom_states) then
280 auto.bottom_states <- StateSet.add nq auto.bottom_states;
281 if not (StateSet.mem q auto.top_states) then
282 auto.top_states <- StateSet.add nq auto.top_states;
285 Hashtbl.add memo_state key nq; nq
287 let trans = Hashtbl.find auto.transitions q in
288 let trans' = List.map (fun (lab, f) -> lab, flip b f) trans in
289 Hashtbl.replace auto.transitions q' trans'