Implement dtgba_sat_minimize().

Joint work with Soheib Baarir.

* src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/dtgbasat.hh: New files.
* src/tgbaalgos/Makefile.am: Add them.
* src/tgbaalgos/postproc.cc, src/tgbaalgos/postproc.hh: Add
a dtgba-sat-minimize option.
* src/tgbatest/ltl2tgba.cc: Add option -RG.
* src/tgbatest/satmin.test: Add more tests.

src/tgbaalgos/Makefile.am

@@ -38,6 +38,7 @@ tgbaalgos_HEADERS = \
   dottydec.hh \
   dotty.hh \
   dtbasat.hh \
+  dtgbasat.hh \
   dupexp.hh \
   eltl2tgba_lacim.hh \
   emptiness.hh \
@@ -86,6 +87,7 @@ libtgbaalgos_la_SOURCES = \
   dotty.cc \
   dottydec.cc \
   dtbasat.cc \
+  dtgbasat.cc \
   dupexp.cc \
   eltl2tgba_lacim.cc \
   emptiness.cc \

src/tgbaalgos/dtgbasat.hh

+// -*- coding: utf-8 -*-
+// Copyright (C) 2013 Laboratoire de Recherche et Développement
+// de l'Epita.
+//
+// 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/>.
+
+#ifndef SPOT_TGBAALGOS_DTGBASAT_HH
+# define SPOT_TGBAALGOS_DTGBASAT_HH
+
+#include <iosfwd>
+#include "tgba/tgba.hh"
+#include "tgba/tgbaexplicit.hh"
+
+namespace spot
+{
+  /// \brief Attempt to reduce a deterministic TGBA with a SAT solver.
+  ///
+  /// \param a the TGBA to reduce.  It should have only one acceptance
+  ///  set and be deterministic.  I.e., it should be a deterministic TBA.
+  ///
+  /// \param cand_nacc is the number of acceptance sets in the result.
+  ///
+  /// This functions attempts to find the smallest TGBA with \a
+  /// cand_nacc acceptance sets that is equivalent to \a a.  If no
+  /// smaller TGBA is found, a null pointer is returned.
+  SPOT_API tgba_explicit_number*
+  dtgba_sat_minimize(const tgba* a, unsigned cand_nacc);
+}
+
+#endif // SPOT_TGBAALGOS_DTGBASAT_HH

src/tgbaalgos/postproc.cc

@@ -30,6 +30,7 @@
 #include "isdet.hh"
 #include "tgba/tgbatba.hh"
 #include "dtbasat.hh"
+#include "dtgbasat.hh"
 #include "complete.hh"
 
 namespace spot
@@ -51,6 +52,7 @@ namespace spot
 	ba_simul_ = opt->get("ba-simul", -1);
 	tba_determinisation_ = opt->get("tba-det", 0);
 	sat_minimize_ = opt->get("sat-minimize", 0);
+	dtgba_sat_minimize_ = opt->get("dtgba-sat-minimize", -1);
       }
   }
 
@@ -300,6 +302,24 @@ namespace spot
 	    delete res;
 	  }
       }
+    else if (dtgba_sat_minimize_ >= 0 && dba && !dba_is_wdba)
+      {
+	const tgba* cmp = tgba_complete(dba);
+	const tgba* res =
+	  dtgba_sat_minimize(cmp,
+			     dtgba_sat_minimize_
+			     ? dtgba_sat_minimize_
+			     : dba->number_of_acceptance_conditions());
+	delete cmp;
+	if (res != 0)
+	  {
+	    delete dba;
+	    dba = scc_filter(res, true);
+	    delete res;
+	  }
+      }
+
+
     // Degeneralize the dba resulting from tba-determinization
     // or sat-minimization (which is a TBA) if requested.
     if (dba && !dba_is_wdba && type_ == BA)

src/tgbaalgos/postproc.hh

@@ -107,6 +107,7 @@ namespace spot
     int ba_simul_;
     bool tba_determinisation_;
     bool sat_minimize_;
+    int dtgba_sat_minimize_;
   };
   /// @}
 }

src/tgbatest/ltl2tgba.cc

@@ -73,6 +73,7 @@
 #include "tgbaalgos/dbacomp.hh"
 #include "tgbaalgos/complete.hh"
 #include "tgbaalgos/dtbasat.hh"
+#include "tgbaalgos/dtgbasat.hh"
 
 #include "taalgos/tgba2ta.hh"
 #include "taalgos/dotty.hh"
@@ -432,6 +433,7 @@ main(int argc, char** argv)
   bool cs_oblig = false;
   bool opt_complete = false;
   int opt_dtbasat = -1;
+  int opt_dtgbasat = -1;
 
   for (;;)
     {
@@ -798,6 +800,14 @@ main(int argc, char** argv)
 	  redopt.reduce_basics = true;
 	  redopt.reduce_size_strictly = true;
         }
+      else if (!strncmp(argv[formula_index], "-RG", 3))
+        {
+	  if (argv[formula_index][3] != 0)
+	    opt_dtgbasat = to_int(argv[formula_index] + 3);
+	  else
+	    opt_dtgbasat = 0;
+          //output = -1;
+        }
       else if (!strcmp(argv[formula_index], "-Rm"))
         {
           opt_minimize = true;
@@ -818,7 +828,7 @@ main(int argc, char** argv)
 	  if (argv[formula_index][3] != 0)
 	    opt_dtbasat = to_int(argv[formula_index] + 3);
 	  else
-	    opt_dtbasat = -1;
+	    opt_dtbasat = 0;
           //output = -1;
         }
       else if (!strcmp(argv[formula_index], "-RT"))
@@ -1523,6 +1533,14 @@ main(int argc, char** argv)
 	  if (satminimized)
 	    a = satminimized;
 	}
+      else if (opt_dtgbasat >= 0)
+	{
+	  tm.start("dtgbasat");
+	  satminimized = dtgba_sat_minimize(a, opt_dtgbasat);
+	  tm.stop("dtgbasat");
+	  if (satminimized)
+	    a = satminimized;
+	}
 
       spot::tgba* complemented = 0;
       if (opt_dbacomp)

src/tgbatest/satmin.test

@@ -86,8 +86,11 @@ G(G!a | F!c | G!b)
 EOF
 
 $ltlcross -F formulas \
-  --timeout=300 \
+  --timeout=60 \
   "$ltl2tgba --det --lbtt %f >%T" \
-  "$ltl2tgba --det --lbtt -x tba-det --lbtt %f >%T" \
-  "$ltl2tgba --det --lbtt -x tba-det,sat-minimize --lbtt %f >%T" \
+  "$ltl2tgba --det --lbtt -x tba-det %f >%T" \
+  "$ltl2tgba --det --lbtt -x tba-det,sat-minimize %f >%T" \
+  "$ltl2tgba --det --lbtt -x tba-det,dtgba-sat-minimize=0 %f >%T" \
+  "$ltl2tgba --det --lbtt -x dtgba-sat-minimize=0 %f >%T" \
+  "$ltl2tgba --det --lbtt -x tba-det,dtgba-sat-minimize=3 %f >%T" \
   --json=det.json