remove twa::compute_support_conditions

Fixes #148.

* spot/twa/twa.hh, spot/twa/twa.cc, spot/kripke/fairkripke.hh,
spot/kripke/fairkripke.cc, spot/ta/tgtaexplicit.hh,
spot/ta/tgtaexplicit.cc, spot/twa/twagraph.hh, spot/twa/twaproduct.hh,
spot/twa/twaproduct.cc, spot/twaalgos/stutter.cc, spot/twa/taatgba.hh,
spot/twa/taatgba.cc: Remove the method.
* spot/taalgos/tgba2ta.cc: Emulate it with a simple loop.
* NEWS: Mention the removal.

NEWS

@@ -82,7 +82,8 @@ New in spot 1.99.7a (not yet released)
   * The twa_safra_complement class has been removed.  Use
     tgba_determinize() and dtwa_complement() instead.
 
-  * The twa::transition_annotation() method has been removed.
+  * The twa::transition_annotation() and
+    twa::compute_support_conditions() methods have been removed.
 
   Python:
 

spot/kripke/fairkripke.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2010, 2014 Laboratoire de Recherche et
+// Copyright (C) 2009, 2010, 2014, 2016 Laboratoire de Recherche et
 // Developpement de l'Epita
 //
 // This file is part of Spot, a model checking library.
@@ -47,11 +47,4 @@ namespace spot
     // this function on a state without successor.
     return acc_cond_;
   }
-
-  bdd
-  fair_kripke::compute_support_conditions(const state* s) const
-  {
-    return state_condition(s);
-  }
-
 }

spot/kripke/fairkripke.hh

@@ -100,8 +100,5 @@ namespace spot
     /// \brief The set of acceptance conditions that label the state \a s.
     virtual acc_cond::mark_t
       state_acceptance_conditions(const state* s) const = 0;
-
-  protected:
-    virtual bdd compute_support_conditions(const state* s) const;
   };
 }

spot/ta/tgtaexplicit.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2010, 2011, 2012, 2014, 2015 Laboratoire de Recherche
+// Copyright (C) 2010, 2011, 2012, 2014, 2015, 2016 Laboratoire de
-// et Developpement de l'Epita (LRDE).
+// Recherche et Developpement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -44,14 +44,6 @@ namespace spot
     return ta_->succ_iter(state);
   }
 
-  bdd
-  tgta_explicit::compute_support_conditions(const spot::state* in) const
-  {
-    const state_ta_explicit* s = down_cast<const state_ta_explicit*>(in);
-    assert(s);
-    return ta_->get_tgba()->support_conditions(s->get_tgba_state());
-  }
-
   bdd_dict_ptr
   tgta_explicit::get_dict() const
   {

spot/ta/tgtaexplicit.hh

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015 Laboratoire de
+// Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015, 2016 Laboratoire
-// Recherche et Développement de l'Epita (LRDE).
+// de Recherche et Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -58,8 +58,6 @@ namespace spot
     virtual twa_succ_iterator*
     succ_iter_by_changeset(const spot::state* s, bdd change_set) const;
   protected:
-    virtual bdd compute_support_conditions(const spot::state* state) const;
-
     ta_explicit_ptr ta_;
   };
 

spot/taalgos/tgba2ta.cc

@@ -413,7 +413,13 @@ namespace spot
       // build Initial states set:
       auto tgba_init_state = tgba_->get_init_state();
 
-      bdd tgba_condition = tgba_->support_conditions(tgba_init_state);
+      bdd tgba_condition = [&]()
+	{
+	  bdd cond = bddfalse;
+	  for (auto i: tgba_->succ(tgba_init_state))
+	    cond |= i->cond();
+	  return cond;
+	}();
 
       bool is_acc = false;
       if (degeneralized)

spot/twa/taatgba.cc

@@ -66,22 +66,6 @@ namespace spot
     return new taa_succ_iterator(s->get_state(), acc());
   }
 
-  bdd
-  taa_tgba::compute_support_conditions(const spot::state* s) const
-  {
-    const spot::set_state* se = down_cast<const spot::set_state*>(s);
-    assert(se);
-    const state_set* ss = se->get_state();
-
-    bdd res = bddtrue;
-    taa_tgba::state_set::const_iterator i;
-    taa_tgba::state::const_iterator j;
-    for (i = ss->begin(); i != ss->end(); ++i)
-      for (j = (*i)->begin(); j != (*i)->end(); ++j)
-	res |= (*j)->condition;
-    return res;
-  }
-
   /*----------.
   | state_set |
   `----------*/

spot/twa/taatgba.hh

@@ -58,8 +58,6 @@ namespace spot
     virtual std::string format_state(const spot::state* state) const = 0;
 
   protected:
-    virtual bdd compute_support_conditions(const spot::state* state)
-      const final;
 
     typedef std::vector<taa_tgba::state_set*> ss_vec;
 

spot/twa/twa.cc

@@ -30,8 +30,7 @@ namespace spot
 {
   twa::twa(const bdd_dict_ptr& d)
     : iter_cache_(nullptr),
-      dict_(d),
+      dict_(d)
-      last_support_conditions_input_(nullptr)
   {
     props = 0U;
     bddaps_ = bddtrue;
@@ -39,27 +38,11 @@ namespace spot
 
   twa::~twa()
   {
-    if (last_support_conditions_input_)
-      last_support_conditions_input_->destroy();
     delete iter_cache_;
     release_named_properties();
     get_dict()->unregister_all_my_variables(this);
   }
 
-  bdd
-  twa::support_conditions(const state* state) const
-  {
-    if (!last_support_conditions_input_
-	|| last_support_conditions_input_->compare(state) != 0)
-      {
-	last_support_conditions_output_ = compute_support_conditions(state);
-	if (last_support_conditions_input_)
-	  last_support_conditions_input_->destroy();
-	last_support_conditions_input_ = state->clone();
-      }
-    return last_support_conditions_output_;
-  }
-
   state*
   twa::project_state(const state* s,
 		      const const_twa_ptr& t) const

spot/twa/twa.hh

@@ -687,21 +687,6 @@ namespace spot
 	iter_cache_ = i;
     }
 
-    /// \brief Get a formula that must hold whatever successor is taken.
-    ///
-    /// \return A formula which must be verified for all successors
-    ///  of \a state.
-    ///
-    /// This can be as simple as \c bddtrue, or more precisely
-    /// the disjunction of the condition of all successors.  This
-    /// is used as an hint by \c succ_iter() to reduce the number
-    /// of successor to compute in a product.
-    ///
-    /// Sub classes should implement compute_support_conditions(),
-    /// this function is just a wrapper that will cache the
-    /// last return value for efficiency.
-    bdd support_conditions(const state* state) const;
-
     /// \brief Get the dictionary associated to the automaton.
     ///
     /// Automata are labeled by Boolean formulas over atomic
@@ -901,12 +886,7 @@ namespace spot
       return acc_.mark(0);
     }
 
-  protected:
-    /// Do the actual computation of tgba::support_conditions().
-    virtual bdd compute_support_conditions(const state* state) const = 0;
-    mutable const state* last_support_conditions_input_;
   private:
-    mutable bdd last_support_conditions_output_;
     std::vector<formula> aps_;
     bdd bddaps_;
 

spot/twa/twagraph.hh

@@ -202,9 +202,6 @@ namespace spot
 
     virtual ~twa_graph()
     {
-      // Prevent this state from being destroyed by ~twa(),
-      // as the state will be destroyed when g_ is destroyed.
-      last_support_conditions_input_ = nullptr;
     }
 
 #ifndef SWIG
@@ -425,14 +422,6 @@ namespace spot
       SPOT_RETURN(g_.is_dead_edge(t));
 #endif
 
-    virtual bdd compute_support_conditions(const state* s) const
-    {
-      bdd sum = bddfalse;
-      for (auto& t: out(state_number(s)))
-	sum |= t.cond;
-      return sum;
-    }
-
     /// Iterate over all edges, and merge those with compatible
     /// extremities and acceptance.
     void merge_edges();

spot/twa/twaproduct.cc

@@ -318,13 +318,6 @@ namespace spot
 
   twa_product::~twa_product()
   {
-    // Prevent these states from being destroyed by ~tgba(): they
-    // will be destroyed before when the pool is destructed.
-    if (last_support_conditions_input_)
-      {
-	last_support_conditions_input_->destroy();
-	last_support_conditions_input_ = nullptr;
-      }
   }
 
   const state*
@@ -359,16 +352,6 @@ namespace spot
       return new twa_succ_iterator_product(li, ri, this, p);
   }
 
-  bdd
-  twa_product::compute_support_conditions(const state* in) const
-  {
-    const state_product* s = down_cast<const state_product*>(in);
-    assert(s);
-    bdd lsc = left_->support_conditions(s->left());
-    bdd rsc = right_->support_conditions(s->right());
-    return lsc & rsc;
-  }
-
   const acc_cond& twa_product::left_acc() const
   {
     return left_->acc();

spot/twa/twaproduct.hh

@@ -102,9 +102,6 @@ namespace spot
     const acc_cond& left_acc() const;
     const acc_cond& right_acc() const;
 
-  protected:
-    virtual bdd compute_support_conditions(const state* state) const;
-
   protected:
     const_twa_ptr left_;
     const_twa_ptr right_;

spot/twaalgos/stutter.cc

@@ -236,12 +236,6 @@ namespace spot
 		+ bdd_format_formula(a_->get_dict(), s->cond()));
       }
 
-    protected:
-      virtual bdd compute_support_conditions(const state*) const override
-      {
-	return bddtrue;
-      }
-
     private:
       const_twa_ptr a_;
       bdd aps_;