scc: get rid of scc_stats

* src/tgbaalgos/scc.cc, src/tgbaalgos/scc.hh: Here.
* src/tgbatest/ltl2tgba.cc: Remove option -k.
* src/tgbatest/sccsimpl.test: Move the only -k test...
* src/tgbatest/scc.test:... here.

src/tgbaalgos/scc.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2009, 2011, 2012, 2013, 2014 Laboratoire de
+// Copyright (C) 2008, 2009, 2011, 2012, 2013, 2014, 2015 Laboratoire
-// Recherche et Développement de l'Epita.
+// de Recherche et Développement de l'Epita.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -27,18 +27,6 @@
 
 namespace spot
 {
-  std::ostream&
-  scc_stats::dump(std::ostream& out) const
-  {
-    out << "total SCCs: " << scc_total << std::endl;
-    out << "accepting SCCs: " << acc_scc << std::endl;
-    out << "dead SCCs: " << dead_scc << std::endl;
-    out << "accepting paths: " << acc_paths << std::endl;
-    out << "dead paths: " << dead_paths << std::endl;
-    return out;
-  }
-
-
   scc_map::scc_map(const const_tgba_ptr& aut)
     : aut_(aut)
   {
@@ -373,101 +361,6 @@ namespace spot
     return scc_map_[n].useful_acc;
   }
 
-  namespace
-  {
-    struct scc_recurse_data
-    {
-      scc_recurse_data() : acc_scc(0), dead_scc(0) {};
-      typedef std::map<unsigned, unsigned> graph_counter;
-      graph_counter acc_paths;
-      graph_counter dead_paths;
-      unsigned acc_scc;
-      unsigned dead_scc;
-    };
-
-    bool scc_recurse(const scc_map& m, unsigned state, scc_recurse_data& data)
-    {
-      // Don't recurse on previously visited states.
-      scc_recurse_data::graph_counter::const_iterator i =
-	data.acc_paths.find(state);
-      if (i != data.acc_paths.end())
-	return i->second > 0;
-
-      const scc_map::succ_type& succ = m.succ(state);
-
-      bool accepting = m.accepting(state);
-      scc_map::succ_type::const_iterator it;
-      unsigned acc_paths = 0;
-      unsigned dead_paths = 0;
-
-      bool paths_accepting = false;
-      for (it = succ.begin(); it != succ.end(); ++it)
-	{
-	  unsigned dest = it->first;
-	  bool path_accepting = scc_recurse(m, dest, data);
-	  paths_accepting |= path_accepting;
-
-	  acc_paths += data.acc_paths[dest];
-	  dead_paths += data.dead_paths[dest];
-	}
-
-      if (accepting)
-	{
-	  ++data.acc_scc;
-	  if (acc_paths == 0)
-	    acc_paths = 1;
-	}
-      else if (!paths_accepting)
-	{
-	  ++data.dead_scc;
-	  if (dead_paths == 0)
-	    dead_paths = 1;
-	}
-
-      data.acc_paths[state] = acc_paths;
-      data.dead_paths[state] = dead_paths;
-
-      return accepting | paths_accepting;
-    }
-
-  }
-
-  scc_stats build_scc_stats(const scc_map& m)
-  {
-    scc_stats res;
-    res.self_loops = m.self_loops();
-    res.scc_total = m.scc_count();
-
-    scc_recurse_data d;
-    unsigned init = m.initial();
-    scc_recurse(m, init, d);
-
-    res.acc_scc = d.acc_scc;
-    res.dead_scc = d.dead_scc;
-    res.acc_paths = d.acc_paths[init];
-    res.dead_paths = d.dead_paths[init];
-
-    res.useless_scc_map.reserve(res.scc_total);
-    for (unsigned n = 0; n < res.scc_total; ++n)
-      {
-	res.useless_scc_map[n] = !d.acc_paths[n];
-	if (m.accepting(n))
-	  {
-	    auto& c = m.useful_acc_of(n);
-	    res.useful_acc.insert(c.begin(), c.end());
-	  }
-      }
-    return res;
-  }
-
-  scc_stats
-  build_scc_stats(const const_tgba_ptr& a)
-  {
-    scc_map m(a);
-    m.build_map();
-    return build_scc_stats(m);
-  }
-
   std::ostream&
   dump_scc_dot(const scc_map& m, std::ostream& out, bool verbose)
   {

src/tgbaalgos/scc.hh

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Laboratoire de
+// Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015
-// Recherche et Développement de l'Epita.
+// Laboratoire de Recherche et Développement de l'Epita.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -31,41 +31,6 @@
 namespace spot
 {
 
-  struct SPOT_API scc_stats
-  {
-    /// Total number of SCCs.
-    unsigned scc_total;
-    /// Total number of accepting SCC.
-    unsigned acc_scc;
-    /// Total number of dead SCC.
-    ///
-    /// An SCC is dead if no accepting SCC is reachable from it.
-    /// Note that an SCC can be neither dead nor accepting.
-    unsigned dead_scc;
-
-    /// Number of maximal accepting paths.
-    ///
-    /// A path is maximal and accepting if it ends in an accepting
-    /// SCC that has only dead (i.e. non accepting) successors, or no
-    /// successors at all.
-    unsigned acc_paths;
-    /// Number of paths to a terminal dead SCC.
-    ///
-    /// A terminal dead SCC is a dead SCC without successors.
-    unsigned dead_paths;
-    unsigned self_loops;
-
-    /// A map of the useless SCCs.
-    std::vector<bool> useless_scc_map;
-
-    /// The set of useful acceptance conditions (i.e. acceptance
-    /// conditions that are not always implied by other acceptance
-    /// conditions).
-    std::set<acc_cond::mark_t> useful_acc;
-
-    std::ostream& dump(std::ostream& out) const;
-  };
-
   /// Build a map of Strongly Connected components in in a TGBA.
   class SPOT_API scc_map
   {
@@ -238,11 +203,6 @@ namespace spot
     unsigned self_loops_; // Self loops count.
  };
 
-  SPOT_API scc_stats
-  build_scc_stats(const const_tgba_ptr& a);
-  SPOT_API scc_stats
-  build_scc_stats(const scc_map& m);
-
   SPOT_API std::ostream&
   dump_scc_dot(const const_tgba_ptr& a,
 	       std::ostream& out, bool verbose = false);

src/tgbatest/ltl2tgba.cc

@@ -273,8 +273,6 @@ syntax(char* prog)
 	    << "Output options (if no emptiness check):" << std::endl
 	    << "  -b    output the automaton in the format of spot"
             << std::endl
-	    << "  -k    display statistics on the automaton (size and SCCs)"
-	    << std::endl
 	    << "  -ks   display statistics on the automaton (size only)"
 	    << std::endl
 	    << "  -kt   display statistics on the automaton (size + "
@@ -553,10 +551,6 @@ checked_main(int argc, char** argv)
 	  output = 17;
 	  hoa_opt = argv[formula_index] + 2;
 	}
-      else if (!strcmp(argv[formula_index], "-k"))
-	{
-	  output = 9;
-	}
       else if (!strcmp(argv[formula_index], "-ks"))
 	{
 	  output = 12;
@@ -1608,10 +1602,6 @@ checked_main(int argc, char** argv)
 		  }
 		break;
 	      }
-	    case 9:
-	      stats_reachable(a).dump(std::cout);
-	      build_scc_stats(a).dump(std::cout);
-	      break;
 	    case 10:
 	      {
 		auto aa =

src/tgbatest/scc.test

@@ -27,6 +27,7 @@ cat >formulas<<EOF
 b U a,3,2,2
 0,0,1,1
 (Gb | F!a) W GFc,22,6,5
+(!a & G(Ga | F(!a & b))) | (a & F(F!a & G(a | !b))),16,7,6
 EOF
 
 run 0 ../../bin/ltl2tgba --low --any --stats='%f,%e,%s,%c' -F formulas/1 >out

src/tgbatest/sccsimpl.test

@@ -171,18 +171,3 @@ test `grep '^acc' out8.txt | wc -w` = 4
 run 0 ../ltl2tgba -R3 -s -RDS -ks \
   '(G(!((b) R (a)))) R (((c) R (!(d))) U (G((a) | (!(G(e))))))' > out9.txt
 grep 'states: 6$' out9.txt
-
-
-# From Spot 1.1 to 1.1.2, this failed with a BDD error because of
-# a bug in scc_filter().
-run 0 ../ltl2tgba -R3 -k '(a) <-> F(Ga <-> F!(b -> a))' >stdout
-cat >expected <<EOF
-transitions: 21
-states: 8
-total SCCs: 6
-accepting SCCs: 3
-dead SCCs: 0
-accepting paths: 4
-dead paths: 0
-EOF
-diff stdout expected