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 2013-03-08 16:24:41 CET by Kim Nguyen>
24 type move = [ `Left | `Right | `Up1 | `Up2 | `Epsilon |`Is1 |`Is2 ]
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;
30 mutable is_left : bool;
31 mutable is_root : bool}
33 type pred_ = move * bool * State.t
34 let make_ctx a b c d e f g =
35 { left = a; right = b; up1 = c; up2 = d; epsilon = e; is_left = f; is_root = g }
37 let print_ctx fmt c = fprintf fmt "{ left : %a; right : %a; up1: %a ; up2 : %a; epsilon : %a ; is_left : %b; is_root : %b }"
38 StateSet.print c.left StateSet.print c.right StateSet.print c.up1 StateSet.print c.up2
39 StateSet.print c.epsilon
42 module Move : (Formula.PREDICATE with type data = pred_ and type ctx = state_ctx ) =
47 type t = move * bool * State.t
48 let equal n1 n2 = n1 = n2
49 let hash n = Hashtbl.hash n
55 include Hcons.Make(Node)
56 let _pr_buff = Buffer.create 10
57 let _str_fmt = formatter_of_buffer _pr_buff
58 let _flush_str_fmt () = pp_print_flush _str_fmt ();
59 let s = Buffer.contents _pr_buff in
60 Buffer.clear _pr_buff; s
63 let _ = _flush_str_fmt () in
65 let m, b, s = a.node in
68 | `Left -> Pretty.down_arrow, Pretty.subscript 1
69 | `Right -> Pretty.down_arrow, Pretty.subscript 2
70 | `Epsilon -> Pretty.epsilon, ""
71 | `Up1 -> Pretty.up_arrow, Pretty.subscript 1
72 | `Up2 -> Pretty.up_arrow, Pretty.subscript 2
73 | `Is1 -> "?", Pretty.subscript 1
74 | `Is2 -> "?", Pretty.subscript 2
76 fprintf _str_fmt "%s%s" dir num;
77 if s != State.dummy then State.print _str_fmt s;
78 let str = _flush_str_fmt () in
79 fprintf ppf "%s%s" (if b then "" else Pretty.lnot) str
81 let l, b, s = p.node in
84 exception NegativeAtom of (move*State.t)
87 let l, b, s = p.node in
88 if s == State.dummy then
92 | _ -> not ctx.is_left
94 let res = dir && not ctx.is_root in
95 res && b || (not (b || res))
97 if not b then raise (NegativeAtom(l,s));
101 | `Right -> ctx.right
104 | `Epsilon -> ctx.epsilon
105 | _ -> StateSet.empty
110 module SFormula = Formula.Make(Move)
113 mutable states : StateSet.t;
114 mutable top_states : StateSet.t;
115 mutable bottom_states: StateSet.t;
116 mutable selection_states: StateSet.t;
117 transitions: (State.t, (QNameSet.t*SFormula.t) list) Hashtbl.t;
120 let next = Uid.make_maker ()
122 let create () = { id = next ();
123 states = StateSet.empty;
124 top_states = StateSet.empty;
125 bottom_states = StateSet.empty;
126 selection_states = StateSet.empty;
127 transitions = Hashtbl.create 17;
131 let get_trans a states tag =
132 StateSet.fold (fun q acc0 ->
134 let trs = Hashtbl.find a.transitions q in
135 List.fold_left (fun acc1 (labs, phi) ->
136 if QNameSet.mem tag labs then (q,phi)::acc1 else acc1) acc0 trs
137 with Not_found -> acc0
141 [add_trans a q labels f] adds a transition [(q,labels) -> f] to the
142 automaton [a] but ensures that transitions remains pairwise disjoint
145 let add_trans a q s f =
146 let trs = try Hashtbl.find a.transitions q with Not_found -> [] in
148 List.fold_left (fun (acup, atrs) (labs, phi) ->
149 let lab1 = QNameSet.inter labs s in
150 let lab2 = QNameSet.diff labs s in
152 if QNameSet.is_empty lab1 then []
153 else [ (lab1, SFormula.or_ phi f) ]
156 if QNameSet.is_empty lab2 then []
157 else [ (lab2, SFormula.or_ phi f) ]
159 (QNameSet.union acup labs, tr1@ tr2 @ atrs)
160 ) (QNameSet.empty, []) trs
162 let rem = QNameSet.diff s cup in
163 let ntrs = if QNameSet.is_empty rem then ntrs
164 else (rem, f) :: ntrs
166 Hashtbl.replace a.transitions q ntrs
168 let _pr_buff = Buffer.create 50
169 let _str_fmt = formatter_of_buffer _pr_buff
170 let _flush_str_fmt () = pp_print_flush _str_fmt ();
171 let s = Buffer.contents _pr_buff in
172 Buffer.clear _pr_buff; s
176 "\nInternal UID: %i@\n\
179 Bottom states: %a@\n\
180 Selection states: %a@\n\
181 Alternating transitions:@\n"
183 StateSet.print a.states
184 StateSet.print a.top_states
185 StateSet.print a.bottom_states
186 StateSet.print a.selection_states;
189 (fun q t acc -> List.fold_left (fun acc (s , f) -> (q,s,f)::acc) acc t)
193 let sorted_trs = List.stable_sort (fun (q1, s1, _) (q2, s2, _) ->
194 let c = State.compare q1 q2 in - (if c == 0 then QNameSet.compare s1 s2 else c))
197 let _ = _flush_str_fmt () in
198 let strs_strings, max_pre, max_all = List.fold_left (fun (accl, accp, acca) (q, s, f) ->
199 let s1 = State.print _str_fmt q; _flush_str_fmt () in
200 let s2 = QNameSet.print _str_fmt s; _flush_str_fmt () in
201 let s3 = SFormula.print _str_fmt f; _flush_str_fmt () in
202 let pre = Pretty.length s1 + Pretty.length s2 in
203 let all = Pretty.length s3 in
204 ( (q, s1, s2, s3) :: accl, max accp pre, max acca all)
205 ) ([], 0, 0) sorted_trs
207 let line = Pretty.line (max_all + max_pre + 6) in
208 let prev_q = ref State.dummy in
209 List.iter (fun (q, s1, s2, s3) ->
210 if !prev_q != q && !prev_q != State.dummy then fprintf fmt " %s\n%!" line;
212 fprintf fmt " %s, %s" s1 s2;
213 fprintf fmt "%s" (Pretty.padding (max_pre - Pretty.length s1 - Pretty.length s2));
214 fprintf fmt " %s %s@\n%!" Pretty.right_arrow s3;
216 fprintf fmt " %s\n%!" line
219 [complete transitions a] ensures that for each state q
220 and each symbols s in the alphabet, a transition q, s exists.
221 (adding q, s -> F when necessary).
224 let complete_transitions a =
225 StateSet.iter (fun q ->
226 let qtrans = Hashtbl.find a.transitions q in
228 List.fold_left (fun rem (labels, _) ->
229 QNameSet.diff rem labels) QNameSet.any qtrans
232 if QNameSet.is_empty rem then qtrans
234 (rem, SFormula.false_) :: qtrans
236 Hashtbl.replace a.transitions q nqtrans
239 (* [normalize_negations a] removes negative atoms in the formula
240 complementing the sub-automaton in the negative states.
241 [TODO check the meaning of negative upward arrows]
243 let normalize_negations auto =
244 let memo_state = Hashtbl.create 17 in
245 let todo = Queue.create () in
247 match SFormula.expr f with
248 Formula.True | Formula.False -> if b then f else SFormula.not_ f
249 | Formula.Or(f1, f2) -> (if b then SFormula.or_ else SFormula.and_)(flip b f1) (flip b f2)
250 | Formula.And(f1, f2) -> (if b then SFormula.and_ else SFormula.or_)(flip b f1) (flip b f2)
251 | Formula.Atom(a) -> begin
252 let l, b', q = Move.node a in
253 if q == State.dummy then if b then f else SFormula.not_ f
255 if b == b' then begin
256 (* a appears positively, either no negation or double negation *)
257 if not (Hashtbl.mem memo_state (q,b)) then Queue.add (q,true) todo;
258 SFormula.atom_ (Move.make (l, true, q))
260 (* need to reverse the atom
261 either we have a positive state deep below a negation
262 or we have a negative state in a positive formula
263 b' = sign of the state
264 b = sign of the enclosing formula
268 (* does the inverted state of q exist ? *)
269 Hashtbl.find memo_state (q, false)
272 (* create a new state and add it to the todo queue *)
273 let nq = State.make () in
274 auto.states <- StateSet.add nq auto.states;
275 if not (StateSet.mem q auto.bottom_states) then
276 auto.bottom_states <- StateSet.add nq auto.bottom_states;
277 if not (StateSet.mem q auto.top_states) then
278 auto.top_states <- StateSet.add nq auto.top_states;
279 Hashtbl.add memo_state (q, false) nq;
280 Queue.add (q, false) todo; nq
282 SFormula.atom_ (Move.make (l, true, not_q))
286 (* states that are not reachable from a selection stat are not interesting *)
287 StateSet.iter (fun q -> Queue.add (q, true) todo) auto.selection_states;
289 while not (Queue.is_empty todo) do
290 let (q, b) as key = Queue.pop todo in
293 Hashtbl.find memo_state key
296 let nq = if b then q else
297 let nq = State.make () in
298 auto.states <- StateSet.add nq auto.states;
299 if not (StateSet.mem q auto.bottom_states) then
300 auto.bottom_states <- StateSet.add nq auto.bottom_states;
301 if not (StateSet.mem q auto.top_states) then
302 auto.top_states <- StateSet.add nq auto.top_states;
305 Hashtbl.add memo_state key nq; nq
307 let trans = Hashtbl.find auto.transitions q in
308 let trans' = List.map (fun (lab, f) -> lab, flip b f) trans in
309 Hashtbl.replace auto.transitions q' trans'