postproc: use tba_determinize_check()

* src/tgbaalgos/postproc.cc: Use tba_determinize_check()
if option "tba-det" is set.
* src/tgbaalgos/postproc.hh (tba_determinize_): New attribute.
* src/tgbatest/det.test: New file.
* src/tgbatest/Makefile.am (TESTS): Add it.

src/tgbaalgos/postproc.cc

@@ -26,6 +26,9 @@
 #include <cstdlib>
 #include "misc/optionmap.hh"
 #include "priv/countstates.hh"
+#include "powerset.hh"
+#include "isdet.hh"
+#include "tgba/tgbatba.hh"
 
 namespace spot
 {
@@ -33,7 +36,7 @@ namespace spot
   postprocessor::postprocessor(const option_map* opt)
     : type_(TGBA), pref_(Small), level_(High),
       degen_reset_(true), degen_order_(false), degen_cache_(true),
-      simul_(-1), scc_filter_(-1), ba_simul_(-1)
+      simul_(-1), scc_filter_(-1), ba_simul_(-1), tba_determinisation_(false)
   {
     if (opt)
       {
@@ -44,6 +47,7 @@ namespace spot
 	simul_limit_ = opt->get("simul-limit", -1);
 	scc_filter_ = opt->get("scc-filter", -1);
 	ba_simul_ = opt->get("ba-simul", -1);
+	tba_determinisation_ = opt->get("tba-det", 0);
       }
   }
 
@@ -210,6 +214,50 @@ namespace spot
 	delete a;
       }
 
+    // If WDBA failed attempt tba-determinization if requested.
+    if (tba_determinisation_ && !wdba && !is_deterministic(sim))
+      {
+	const tgba* tmpd = 0;
+	if (pref_ == Deterministic
+	    && f
+	    && f->is_syntactic_recurrence()
+	    && sim->number_of_acceptance_conditions() > 1)
+	  tmpd = new tgba_tba_proxy(sim);
+
+	// This threshold is arbitrary.  For producing Small automata,
+	// we assume that a deterministic automaton that is twice the
+	// size of the original will never get reduced to a smaller
+	// one.  For Deterministic automata, we accept automata that
+	// are 4 times bigger.  The larger the value, the more likely
+	// the cycle enumeration algorithm will encounter an automaton
+	// that takes *eons* to explore.
+	const tgba* in = tmpd ? tmpd : sim;
+	const tgba* tmp =
+	  tba_determinize_check(in, (pref_ == Small) ? 2 : 4, f);
+	if (tmp != 0 && tmp != in)
+	  {
+	    // There is no point in running the reverse simulation on
+	    // a deterministic automaton, since all prefixes are
+	    // unique.
+	    wdba = simulation(tmp);
+	    delete tmp;
+	    // Degeneralize the result (which is a TBA) if requested.
+	    if (type_ == BA)
+	      {
+		const tgba* d = degeneralize(wdba);
+		delete wdba;
+		wdba = d;
+	      }
+	  }
+	delete tmpd;
+	if (wdba && pref_ == Deterministic)
+	  {
+	    // disregard the result of the simulation.
+	    delete sim;
+	    sim = 0;
+	  }
+      }
+
     if (wdba && sim)
       {
 	if (count_states(wdba) > count_states(sim))

src/tgbaalgos/postproc.hh

@@ -105,6 +105,7 @@ namespace spot
     int simul_limit_;
     int scc_filter_;
     int ba_simul_;
+    bool tba_determinisation_;
   };
   /// @}
 }

src/tgbatest/Makefile.am

@@ -81,6 +81,7 @@ TESTS = \
   tgbaread.test \
   renault.test \
   nondet.test \
+  det.test \
   neverclaimread.test \
   dstar.test \
   readsave.test \

src/tgbatest/det.test

@@ -0,0 +1,88 @@
+#!/bin/sh
+# -*- coding: utf-8 -*-
+# Copyright (C) 2013 Laboratoire de Recherche et Développement
+# de l'Epita (LRDE).
+#
+# This file is part of Spot, a model checking library.
+#
+# Spot is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Spot is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. ./defs
+set -e
+
+ltl2tgba=../../bin/ltl2tgba
+
+cat >formulas <<'EOF'
+1,14,X((a M F((!c & !b) | (c & b))) W (G!c U b))
+1,5,X(((a & b) R (!a U !c)) R b)
+1,10,XXG(Fa U Xb)
+1,5,(!a M !b) W F!c
+1,3,(b & Fa & GFc) R a
+1,2,(a R (b W a)) W G(!a M (c | b))
+1,11,(Fa W b) R (Fc | !a)
+1,7,X(G(!a M !b) | G(a | G!a))
+1,2,Fa W Gb
+1,3,Ga | GFb
+1,9,G((G!a & ((!b & X!c) | (b & Xc))) | (Fa & ((!b & Xc) | (b & X!c))))
+1,5,a M G(F!b | X!a)
+1,4,G!a R XFb
+1,4,XF(!a | GFb)
+1,6,G(F!a U !a) U Xa
+1,5,(a | G(a M !b)) W Fc
+1,6,Fa W Xb
+1,10,X(a R ((!b & F!c) M X!a))
+1,2,XG!a R Fb
+1,4,GFc | (a & Fb)
+1,6,X(a R (Fb R F!b))
+1,2,G(Xa M Fa)
+1,4,X(Gb | GFa)
+1,9,X(Gc | XG((b & Ga) | (!b & F!a)))
+1,2,Ga R Fb
+1,3,G(a U (b | X((!c & !a) | (a & c))))
+1,5,XG((G!a & F!b) | (Fa & (a | Gb)))
+1,10,(a U X!a) | XG(!b & XFc)
+1,4,X(G!a | GFa)
+1,4,G(G!a | F!c | G!b)
+EOF
+
+cut -d, -f3 <formulas | $ltl2tgba -x tba-det --det --stats '%d,%s,%f' -F - > out
+diff formulas out
+
+cat >in.tgba <<'EOF'
+acc = "1";
+"1", "2", "a", "1";
+"1", "1", "!a",;
+"2", "3", "a", "1";
+"2", "1", "!a",;
+"3", "3", "a",;
+"3", "1", "!a",;
+EOF
+
+cat >ex.tgba <<'EOF'
+acc = "1";
+"1", "2", "a",;
+"1", "1", "!a",;
+"1", "-1", "!a",;
+"2", "3", "a",;
+"2", "1", "!a",;
+"-1", "-1", "!a", "1";
+"3", "3", "a",;
+"3", "-3", "a",;
+"3", "1", "!a",;
+"-3", "-3", "a", "1";
+"-3", "-1", "!a", "1";
+EOF
+
+run 0 ../ltl2tgba -b -DC -X in.tgba > out.tgba
+cmp out.tgba ex.tgba