simulation.cc 47.7 KB
Newer Older
Thomas Badie's avatar
Thomas Badie committed
1
// -*- coding: utf-8 -*-
2
// Copyright (C) 2012, 2013, 2014 Laboratoire de Recherche et Développement
Thomas Badie's avatar
Thomas Badie committed
3
// de l'Epita (LRDE).
Thomas Badie's avatar
Thomas Badie committed
4
5
6
7
8
//
// 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
9
// the Free Software Foundation; either version 3 of the License, or
Thomas Badie's avatar
Thomas Badie committed
10
11
12
13
14
15
16
17
// (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
18
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
Thomas Badie's avatar
Thomas Badie committed
19
20
21
22

#include <queue>
#include <map>
#include <utility>
Thomas Badie's avatar
Thomas Badie committed
23
24
#include <cmath>
#include <limits>
Thomas Badie's avatar
Thomas Badie committed
25
26
#include "tgba/tgbaexplicit.hh"
#include "simulation.hh"
27
#include "priv/acccompl.hh"
Thomas Badie's avatar
Thomas Badie committed
28
29
30
#include "misc/minato.hh"
#include "tgba/bddprint.hh"
#include "tgbaalgos/reachiter.hh"
31
#include "tgbaalgos/sccfilter.hh"
Thomas Badie's avatar
Thomas Badie committed
32
33
34
#include "tgbaalgos/scc.hh"
#include "tgbaalgos/dupexp.hh"
#include "tgbaalgos/dotty.hh"
Thomas Badie's avatar
Thomas Badie committed
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66

// The way we developed this algorithm is the following: We take an
// automaton, and reverse all these acceptance conditions.  We reverse
// them to go make the meaning of the signature easier. We are using
// bdd, and we want to let it make all the simplification. Because of
// the format of the acceptance condition, it doesn't allow easy
// simplification. Instead of encoding them as: "a!b!c + !ab!c", we
// use them as: "ab". We complement them because we want a
// simplification if the condition of the transition A implies the
// transition of B, and if the acceptance condition of A is included
// in the acceptance condition of B. To let the bdd makes the job, we
// revert them.

// Then, to check if a transition i-dominates another, we'll use the bdd:
// "sig(transA) = cond(trans) & acc(trans) & implied(class(trans->state))"
// Idem for sig(transB). The 'implied'
// (represented by a hash table 'relation_' in the implementation) is
// a conjunction of all the class dominated by the class of the
// destination. This is how the relation is included in the
// signature. It makes the simplifications alone, and the work is
// done.  The algorithm is cut into several step:
//
// 1. Run through the tgba and switch the acceptance condition to their
//    negation, and initializing relation_ by the 'init_ -> init_' where
//    init_ is the bdd which represents the class. This function is the
//    constructor of Simulation.
// 2. Enter in the loop (run).
//    - Rename the class.
//    - run through the automaton and computing the signature of each
//      state. This function is `update_sig'.
//    - Enter in a double loop to adapt the partial order, and set
//      'relation_' accordingly. This function is `update_po'.
67
// 3. Rename the class (to actualize the name in the previous_class and
Thomas Badie's avatar
Thomas Badie committed
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
//    in relation_).
// 4. Building an automaton with the result, with the condition:
// "a transition in the original automaton appears in the simulated one
// iff this transition is included in the set of i-maximal neighbour."
// This function is `build_output'.
// The automaton simulated is recomplemented to come back to its initial
// state when the object Simulation is destroyed.
//
// Obviously these functions are possibly cut into several little one.
// This is just the general development idea.

// How to use isop:
// I need all variable non_acceptance & non_class.
// bdd_support(sig(X)): All var
// bdd_support(sig(X)) - allacc - allclassvar


Thomas Badie's avatar
Thomas Badie committed
85
86
87
88
89
90
91
// We have had the Cosimulation by changing the acc_compl_automaton by
// adding a template parameter. If this parameter is set to true, we
// record the transition in the opposite direction (we just swap
// sources and destination). In the build result we are making the
// same thing to rebuild the automaton.
// In the signature,

Thomas Badie's avatar
Thomas Badie committed
92
93
94
95
// TODO LIST: Play on the order of the selection in the
// dont_care_simulation. The good place to work is in add_to_map_imply.


Thomas Badie's avatar
Thomas Badie committed
96
97
98
99
100
101
102
namespace spot
{
  namespace
  {
    // Some useful typedef:

    // Used to get the signature of the state.
103
104
105
    typedef std::unordered_map<const state*, bdd,
			       state_ptr_hash,
			       state_ptr_equal> map_state_bdd;
106
    typedef std::vector<bdd> vector_state_bdd;
Thomas Badie's avatar
Thomas Badie committed
107

Thomas Badie's avatar
Thomas Badie committed
108
109
110
    typedef std::map<const state*, const state*,
                     state_ptr_less_than> map_state_state;

111
112
    typedef std::vector<const state*> vector_state_state;

Thomas Badie's avatar
Thomas Badie committed
113

Thomas Badie's avatar
Thomas Badie committed
114
115
116
117
    // Get the list of state for each class.
    typedef std::map<bdd, std::list<const state*>,
                     bdd_less_than> map_bdd_lstate;

Thomas Badie's avatar
Thomas Badie committed
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
    typedef std::map<bdd, const state*,
                     bdd_less_than> map_bdd_state;

    // Our constraint: (state_src, state_dst) = to_add.
    // We define the couple of state as the key of the constraint.
    typedef std::pair<const state*, const state*> constraint_key;

    // But we need a comparator for that key.
    struct constraint_key_comparator
    {
      bool operator()(const constraint_key& l,
                      const constraint_key& r) const
      {
        if (l.first->compare(r.first) < 0)
          return true;
        else
          if (l.first->compare(r.first) > 0)
            return false;

        if (l.second->compare(r.second) < 0)
          return true;
        else
          if (l.second->compare(r.second) > 0)
            return false;

        return false;
      }
    };

    // The full definition of the constraint.
    typedef std::map<constraint_key, bdd,
                     constraint_key_comparator> map_constraint;

151
    typedef std::tuple<const state*, const state*, bdd> constraint;
Thomas Badie's avatar
Thomas Badie committed
152
153
154
155
156
157

    // Helper to create the map of constraints to give to the
    // simulation.
    void add_to_map(const std::list<constraint>& list,
                    map_constraint& feed_me)
    {
158
      for (auto& p: list)
159
160
161
	feed_me.insert(std::make_pair(std::make_pair(std::get<0>(p),
						     std::get<1>(p)),
				      std::get<2>(p)));
Thomas Badie's avatar
Thomas Badie committed
162
163
164
165
166
    }


    // This class helps to compare two automata in term of
    // size.
167
168
169
170
171
172
173
174
    struct automaton_size
    {
      automaton_size()
        : transitions(0),
          states(0)
      {
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
175
      inline bool operator!=(const automaton_size& r)
176
177
178
179
      {
        return transitions != r.transitions || states != r.states;
      }

Thomas Badie's avatar
Thomas Badie committed
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
      inline bool operator<(const automaton_size& r)
      {
        if (states < r.states)
          return true;
        if (states > r.states)
          return false;

        if (transitions < r.transitions)
          return true;
        if (transitions > r.transitions)
          return false;

        return false;
      }

      inline bool operator>(const automaton_size& r)
      {
        if (states < r.states)
          return false;
        if (states > r.states)
          return true;

        if (transitions < r.transitions)
          return false;
        if (transitions > r.transitions)
          return true;

        return false;
      }

210
211
212
      int transitions;
      int states;
    };
Thomas Badie's avatar
Thomas Badie committed
213

Thomas Badie's avatar
Thomas Badie committed
214
215
    // This class takes an automaton, and return a (maybe new)
    // automaton. If Cosimulation is equal to true, we create a new
216
    // automaton. Otherwise, we reuse the input one.  The returned
Thomas Badie's avatar
Thomas Badie committed
217
218
219
    // automaton is similar to the old one, except that the acceptance
    // condition on the transitions are complemented.
    // There is a specialization below.
220
    template <bool Cosimulation, bool Sba>
221
    class acc_compl_automaton:
Thomas Badie's avatar
Thomas Badie committed
222
      public tgba_reachable_iterator_depth_first
223
    {
Thomas Badie's avatar
Thomas Badie committed
224
    public:
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
      acc_compl_automaton(const tgba* a)
	: tgba_reachable_iterator_depth_first(a),
	  ea_(down_cast<tgba_digraph*>(const_cast<tgba*>(a))),
	  ac_(ea_->all_acceptance_conditions(),
	      ea_->neg_acceptance_conditions())
      {
	assert(ea_);
	out_ = ea_;
      }

      void process_link(const state*, int,
			const state*, int,
			const tgba_succ_iterator* si)
      {
	bdd& acc = ea_->trans_data(si).acc;
	acc = ac_.complement(acc);
      }


      virtual void
      end()
      {
	unsigned s = seen.size();
	old_name_.resize(s);
	for (unsigned i = 0; i < s; ++i)
	  old_name_[i] = ea_->state_from_number(i);
	size = s;
      }

      ~acc_compl_automaton()
      {
      }
Thomas Badie's avatar
Thomas Badie committed
257
258
259

    public:
      size_t size;
260
261
      tgba_digraph* out_;
      vector_state_state old_name_;
Thomas Badie's avatar
Thomas Badie committed
262
263

    private:
264
      tgba_digraph* ea_;
Thomas Badie's avatar
Thomas Badie committed
265
266
267
      acc_compl ac_;
    };

268
269
270
271
    // The specialization for Cosimulation equals to true: We copy the
    // automaton and transpose it at the same time.
    template <bool Sba>
    class acc_compl_automaton<true, Sba>:
Thomas Badie's avatar
Thomas Badie committed
272
273
      public tgba_reachable_iterator_depth_first
    {
Thomas Badie's avatar
Thomas Badie committed
274
    public:
275
276
277
      acc_compl_automaton(const tgba* a)
      : tgba_reachable_iterator_depth_first(a),
	size(0),
278
        out_(new tgba_digraph(a->get_dict())),
279
280
	ac_(a->all_acceptance_conditions(),
	    a->neg_acceptance_conditions()),
281
282
	current_max(0),
 	ea_(down_cast<tgba_digraph*>(const_cast<tgba*>(a)))
Thomas Badie's avatar
Thomas Badie committed
283
      {
284
	a->get_dict()->register_all_variables_of(a, out_);
285
	out_->copy_acceptance_conditions_of(a);
286
287
288

        const state* init_ = a->get_init_state();
	init_->destroy();
Thomas Badie's avatar
Thomas Badie committed
289
290
      }

291
292
293
294
      virtual void
      process_link(const state*, int src,
		   const state* out_s, int dst,
		   const tgba_succ_iterator* si)
Thomas Badie's avatar
Thomas Badie committed
295
      {
296
297
298
299
300
301
302
	auto& g = out_->get_graph();
	{
	  // Create as many states as needed.
	  unsigned m = std::max(src - 1, dst - 1);
	  for (unsigned ms = out_->num_states(); ms <= m; ++ms)
	    g.new_state();
	}
Thomas Badie's avatar
Thomas Badie committed
303

304
	bdd acc;
305
306
	if (!Sba)
	  {
307
	    acc = ac_.complement(si->current_acceptance_conditions());
308
309
310
311
312
313
	  }
	else
	  {
	    // If the acceptance is interpreted as state-based, to
	    // apply the reverse simulation on a SBA, we should pull
	    // the acceptance of the destination state on its incoming
314
	    // arcs (which now become outgoing arcs after
315
	    // transposition).
316
317
	    acc = bddfalse;
	    for (auto it: ea_->succ(out_s))
318
	      {
319
		acc = ac_.complement(it->current_acceptance_conditions());
320
		break;
321
322
	      }
	  }
323
324
325
326

	// Note the order of src and dst: the transition is reversed.
	g.new_transition(dst - 1, src - 1,
			 si->current_condition(), acc);
Thomas Badie's avatar
Thomas Badie committed
327
328
      }

329
      virtual void end()
Thomas Badie's avatar
Thomas Badie committed
330
      {
331
332
333
334
335
	unsigned s = this->seen.size();
	old_name_.resize(s);
	for (unsigned i = 0; i < s; ++i)
	  old_name_[i] = ea_->state_from_number(i);
	size = s;
Thomas Badie's avatar
Thomas Badie committed
336
337
      }

338
      ~acc_compl_automaton()
Thomas Badie's avatar
Thomas Badie committed
339
340
341
342
343
      {
      }

    public:
      size_t size;
344
345
      tgba_digraph* out_;
      vector_state_state old_name_;
Thomas Badie's avatar
Thomas Badie committed
346
347

    private:
348
      acc_compl ac_;
Thomas Badie's avatar
Thomas Badie committed
349
      unsigned current_max;
350
      tgba_digraph* ea_;
351
    };
Thomas Badie's avatar
Thomas Badie committed
352

Thomas Badie's avatar
Thomas Badie committed
353
    // The direct_simulation. If Cosimulation is true, we are doing a
354
355
    // cosimulation.
    template <bool Cosimulation, bool Sba>
356
    class direct_simulation
Thomas Badie's avatar
Thomas Badie committed
357
    {
Thomas Badie's avatar
Thomas Badie committed
358
    protected:
359
360
361
      // Shortcut used in update_po and go_to_next_it.
      typedef std::map<bdd, bdd, bdd_less_than> map_bdd_bdd;
    public:
Thomas Badie's avatar
Thomas Badie committed
362
363
364
365
366
367
368
      direct_simulation(const tgba* t, const map_constraint* map_cst = 0)
        : a_(0),
          po_size_(0),
          all_class_var_(bddtrue),
          map_cst_(map_cst),
          original_(t),
          dont_delete_old_(false)
369
      {
Thomas Badie's avatar
Thomas Badie committed
370
371
372
373
374
375
376
377
378
379
        // We need to do a dupexp for being able to run scc_map later.
        // new_original_ is the map that contains the relation between
        // the names (addresses) of the states in the automaton
        // returned by dupexp, and in automaton given in argument to
        // the constructor.
        a_ = tgba_dupexp_dfs(t, new_original_);
        scc_map_ = new scc_map(a_);
        scc_map_->build_map();
        old_a_ = a_;

380

381
	acc_compl_automaton<Cosimulation, Sba> acc_compl(a_);
382
383
384
385
386

	// We'll start our work by replacing all the acceptance
	// conditions by their complement.
	acc_compl.run();

Thomas Badie's avatar
Thomas Badie committed
387
388
        // Contains the relation between the names of the states in
        // the automaton returned by the complementation and the one
389
        // passed to the constructor of acc_compl.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
390
	std::swap(old_name_, acc_compl.old_name_);
Thomas Badie's avatar
Thomas Badie committed
391

392
393
	a_ = acc_compl.out_;

Thomas Badie's avatar
Thomas Badie committed
394
395
        initial_state = a_->get_init_state();

396
397
398
399
400
401
402
403
404
	// We use the previous run to know the size of the
	// automaton, and to class all the reachable states in the
	// map previous_class_.
	size_a_ = acc_compl.size;

	// Now, we have to get the bdd which will represent the
	// class. We register one bdd by state, because in the worst
	// case, |Class| == |State|.
	unsigned set_num = a_->get_dict()
405
	  ->register_anonymous_variables(size_a_ + 1, this);
406

407
408
        all_acceptance_conditions_ = a_->all_acceptance_conditions();
        all_proms_ = bdd_support(all_acceptance_conditions_);
Thomas Badie's avatar
Thomas Badie committed
409

Thomas Badie's avatar
Thomas Badie committed
410
411
        bdd_initial = bdd_ithvar(set_num++);
	bdd init = bdd_ithvar(set_num++);
412
413
414

	used_var_.push_back(init);

415
416
417
418
	// Initialize all classes to init.
	previous_class_.resize(size_a_);
	for (unsigned s = 0; s < size_a_; ++s)
	  previous_class_[s] = init;
Thomas Badie's avatar
Thomas Badie committed
419

420
421
422
423
	// Put all the anonymous variable in a queue, and record all
	// of these in a variable all_class_var_ which will be used
	// to understand the destination part in the signature when
	// building the resulting automaton.
424
	all_class_var_ = init;
425
	for (unsigned i = set_num; i < set_num + size_a_ - 1; ++i)
Thomas Badie's avatar
Thomas Badie committed
426
427
428
429
430
          {
            free_var_.push(i);
            all_class_var_ &= bdd_ithvar(i);
          }

431
432
	relation_[init] = init;
      }
Thomas Badie's avatar
Thomas Badie committed
433
434


435
436
437
      // Reverse all the acceptance condition at the destruction of
      // this object, because it occurs after the return of the
      // function simulation.
Thomas Badie's avatar
Thomas Badie committed
438
      virtual ~direct_simulation()
439
      {
440
	a_->get_dict()->unregister_all_my_variables(this);
Thomas Badie's avatar
Thomas Badie committed
441
        delete scc_map_;
442

Thomas Badie's avatar
Thomas Badie committed
443
        if (!dont_delete_old_)
444
445
	  delete old_a_;
        // a_ is a new automaton only if we are doing a cosimulation.
Thomas Badie's avatar
Thomas Badie committed
446
447
        if (Cosimulation)
          delete a_;
448
      }
Thomas Badie's avatar
Thomas Badie committed
449

450
      // Update the name of the classes.
451
452
453
454
455
456
      void update_previous_class()
      {
	std::list<bdd>::iterator it_bdd = used_var_.begin();

	// We run through the map bdd/list<state>, and we update
	// the previous_class_ with the new data.
457
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
458
          {
459
460
461
462
463
464
465
466
	    // If the signature of a state is bddfalse (no
	    // transitions) the class of this state is bddfalse
	    // instead of an anonymous variable. It allows
	    // simplifications in the signature by removing a
	    // transition which has as a destination a state with
	    // no outgoing transition.
	    if (p.first == bddfalse)
	      for (auto s: p.second)
467
		previous_class_[a_->state_number(s)] = bddfalse;
468
469
	    else
	      for (auto s: p.second)
470
		previous_class_[a_->state_number(s)] = *it_bdd;
471
	    ++it_bdd;
Thomas Badie's avatar
Thomas Badie committed
472
          }
473
474
      }

Thomas Badie's avatar
Thomas Badie committed
475
      void main_loop()
476
477
478
479
480
      {
	unsigned int nb_partition_before = 0;
	unsigned int nb_po_before = po_size_ - 1;
	while (nb_partition_before != bdd_lstate_.size()
	       || nb_po_before != po_size_)
Thomas Badie's avatar
Thomas Badie committed
481
          {
482
            update_previous_class();
Thomas Badie's avatar
Thomas Badie committed
483
484
485
486
487
488
489
490
            nb_partition_before = bdd_lstate_.size();
            bdd_lstate_.clear();
            nb_po_before = po_size_;
            po_size_ = 0;
            update_sig();
            go_to_next_it();
          }

491
	update_previous_class();
Thomas Badie's avatar
Thomas Badie committed
492
493
494
495
496
497
      }

      // The core loop of the algorithm.
      tgba* run()
      {
        main_loop();
498
499
	return build_result();
      }
Thomas Badie's avatar
Thomas Badie committed
500

501
502
503
      // Take a state and compute its signature.
      bdd compute_sig(const state* src)
      {
Thomas Badie's avatar
Thomas Badie committed
504
        bdd res = bddfalse;
Thomas Badie's avatar
Thomas Badie committed
505

506
        for (auto sit: a_->succ(src))
Thomas Badie's avatar
Thomas Badie committed
507
508
          {
            const state* dst = sit->current_state();
Thomas Badie's avatar
Thomas Badie committed
509
            bdd acc = bddtrue;
Thomas Badie's avatar
Thomas Badie committed
510

511
512
513
514
515
516
517
	    map_constraint::const_iterator it;
	    // We are using new_original_[old_name_[...]] because
	    // we have the constraints in the original automaton
	    // which has been duplicated twice to get the current
	    // automaton.
	    if (map_cst_
		&& ((it = map_cst_
518
519
520
		     ->find(std::make_pair
			    (new_original_[old_name_[a_->state_number(src)]],
			     new_original_[old_name_[a_->state_number(dst)]])))
521
522
523
524
525
526
527
528
529
530
531
532
533
		    != map_cst_->end()))
	      {
		acc = it->second;
	      }
	    else
	      {
		acc = sit->current_acceptance_conditions();
	      }

	    // to_add is a conjunction of the acceptance condition,
	    // the label of the transition and the class of the
	    // destination and all the class it implies.
	    bdd to_add = acc & sit->current_condition()
534
	      & relation_[previous_class_[a_->state_number(dst)]];
Thomas Badie's avatar
Thomas Badie committed
535

536
537
538
	    res |= to_add;
	    dst->destroy();
	  }
Thomas Badie's avatar
Thomas Badie committed
539

Thomas Badie's avatar
Thomas Badie committed
540
        // When we Cosimulate, we add a special flag to differentiate
541
        // the initial state from the other.
Thomas Badie's avatar
Thomas Badie committed
542
543
544
545
        if (Cosimulation && initial_state == src)
          res |= bdd_initial;

        return res;
546
547
      }

Thomas Badie's avatar
Thomas Badie committed
548

549
550
      void update_sig()
      {
551
552
553
554
555
	for (unsigned s = 0; s < size_a_; ++s)
	  {
	    const state* src = a_->state_from_number(s);
	    bdd_lstate_[compute_sig(src)].push_back(src);
	  }
556
      }
Thomas Badie's avatar
Thomas Badie committed
557
558


559
560
561
562
      // This method rename the color set, update the partial order.
      void go_to_next_it()
      {
	int nb_new_color = bdd_lstate_.size() - used_var_.size();
Thomas Badie's avatar
Thomas Badie committed
563

Thomas Badie's avatar
Thomas Badie committed
564
565
566

        // If we have created more partitions, we need to use more
        // variables.
567
	for (int i = 0; i < nb_new_color; ++i)
Thomas Badie's avatar
Thomas Badie committed
568
569
570
571
572
573
          {
            assert(!free_var_.empty());
            used_var_.push_back(bdd_ithvar(free_var_.front()));
            free_var_.pop();
          }

Thomas Badie's avatar
Thomas Badie committed
574
575
576

        // If we have reduced the number of partition, we 'free' them
        // in the free_var_ list.
577
578
579
580
581
582
583
584
585
586
587
	for (int i = 0; i > nb_new_color; --i)
          {
            assert(!used_var_.empty());
            free_var_.push(bdd_var(used_var_.front()));
            used_var_.pop_front();
          }


	assert((bdd_lstate_.size() == used_var_.size())
               || (bdd_lstate_.find(bddfalse) != bdd_lstate_.end()
                   && bdd_lstate_.size() == used_var_.size() + 1));
Thomas Badie's avatar
Thomas Badie committed
588

589
590
591
592
593
594
595
	// Now we make a temporary hash_table which links the tuple
	// "C^(i-1), N^(i-1)" to the new class coloring.  If we
	// rename the class before updating the partial order, we
	// loose the information, and if we make it after, I can't
	// figure out how to apply this renaming on rel_.
	// It adds a data structure but it solves our problem.
	map_bdd_bdd now_to_next;
Thomas Badie's avatar
Thomas Badie committed
596

597
	std::list<bdd>::iterator it_bdd = used_var_.begin();
Thomas Badie's avatar
Thomas Badie committed
598

599
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
600
          {
601
602
603
604
605
606
607
608
609
	    // If the signature of a state is bddfalse (no
	    // transitions) the class of this state is bddfalse
	    // instead of an anonymous variable. It allows
	    // simplifications in the signature by removing a
	    // transition which has as a destination a state with
	    // no outgoing transition.
	    now_to_next[p.first] =
	      (p.first == bddfalse) ? bddfalse : *it_bdd;
	    ++it_bdd;
Thomas Badie's avatar
Thomas Badie committed
610
611
          }

Thomas Badie's avatar
Thomas Badie committed
612
	update_po(now_to_next, relation_);
613
614
      }

Thomas Badie's avatar
Thomas Badie committed
615
616
617
618
619
620
621
622
623
      // This function computes the new po with previous_class_ and
      // the argument. `now_to_next' contains the relation between the
      // signature and the future name of the class.  We need a
      // template parameter because we use this function with a
      // map_bdd_bdd, but later, we need a list_bdd_bdd. So to
      // factorize some code we use a template.
      template <typename container_bdd_bdd>
      void update_po(const container_bdd_bdd& now_to_next,
                     map_bdd_bdd& relation)
624
625
626
627
628
629
630
631
      {
	// This loop follows the pattern given by the paper.
	// foreach class do
	// |  foreach class do
	// |  | update po if needed
	// |  od
	// od

Thomas Badie's avatar
Thomas Badie committed
632
633
	for (typename container_bdd_bdd::const_iterator it1
               = now_to_next.begin();
634
635
	     it1 != now_to_next.end();
	     ++it1)
Thomas Badie's avatar
Thomas Badie committed
636
637
          {
            bdd accu = it1->second;
Thomas Badie's avatar
Thomas Badie committed
638
639
            for (typename container_bdd_bdd::const_iterator it2
                   = now_to_next.begin();
Thomas Badie's avatar
Thomas Badie committed
640
641
                 it2 != now_to_next.end();
                 ++it2)
Thomas Badie's avatar
Thomas Badie committed
642
643
644
645
646
647
648
649
650
651
652
              {
                // Skip the case managed by the initialization of accu.
                if (it1 == it2)
                  continue;

                if (bdd_implies(it1->first, it2->first))
                  {
                    accu &= it2->second;
                    ++po_size_;
                  }
              }
Thomas Badie's avatar
Thomas Badie committed
653
            relation[it1->second] = accu;
Thomas Badie's avatar
Thomas Badie committed
654
          }
655
656
      }

657
658
659
660
661
662
663
      automaton_size get_stat() const
      {
        assert(stat.states != 0);

        return stat;
      }

Thomas Badie's avatar
Thomas Badie committed
664
665
666
667
668
669
670
671
      bool result_is_deterministic() const
      {
        assert(stat.states != 0);

        return res_is_deterministic;
      }


672

673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
      // Build the minimal resulting automaton.
      tgba* build_result()
      {
	// Now we need to create a state per partition. But the
	// problem is that we don't know exactly the class. We know
	// that it is a combination of the acceptance condition
	// contained in all_class_var_. So we need to make a little
	// workaround. We will create a map which will associate bdd
	// and unsigned.
	std::map<bdd, unsigned, bdd_less_than> bdd2state;
	unsigned int current_max = 0;

	// We have all the a_'s acceptances conditions
	// complemented.  So we need to complement it when adding a
	// transition.  We *must* keep the complemented because it
	// is easy to know if an acceptance condition is maximal or
	// not.
Thomas Badie's avatar
Thomas Badie committed
690
	acc_compl reverser(all_acceptance_conditions_,
691
692
			   a_->neg_acceptance_conditions());

693
694
695
696
	bdd_dict* d = a_->get_dict();
	tgba_explicit_number* res = new tgba_explicit_number(d);
	d->register_all_variables_of(a_, res);
	res->set_acceptance_conditions(all_acceptance_conditions_);
697

Thomas Badie's avatar
Thomas Badie committed
698
	bdd sup_all_acc = bdd_support(all_acceptance_conditions_);
699
700
701
702
	// Non atomic propositions variables (= acc and class)
	bdd nonapvars = sup_all_acc & bdd_support(all_class_var_);

	// Create one state per partition.
703
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
704
705
          {
            res->add_state(++current_max);
706
            bdd part = previous_class_[a_->state_number(*p.second.begin())];
Thomas Badie's avatar
Thomas Badie committed
707
708
709

            // The difference between the two next lines is:
            // the first says "if you see A", the second "if you
710
            // see A and all the classes implied by it".
Thomas Badie's avatar
Thomas Badie committed
711
712
713
714
            bdd2state[part] = current_max;
            bdd2state[relation_[part]] = current_max;
          }

715
716
717
718
719
	// Acceptance of states.  Only used if Sba && Cosimulation.
	std::vector<bdd> accst;
	if (Sba && Cosimulation)
	  accst.resize(current_max + 1, bddfalse);

720
721
722
        stat.states = bdd_lstate_.size();
        stat.transitions = 0;

Thomas Badie's avatar
Thomas Badie committed
723
724
725
        unsigned nb_satoneset = 0;
        unsigned nb_minato = 0;

726
727
	// For each partition, we will create
	// all the transitions between the states.
728
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
729
730
          {
            // Get the signature.
731
            bdd sig = compute_sig(*(p.second.begin()));
Thomas Badie's avatar
Thomas Badie committed
732

Thomas Badie's avatar
Thomas Badie committed
733
734
735
            if (Cosimulation)
              sig = bdd_compose(sig, bddfalse, bdd_var(bdd_initial));

Thomas Badie's avatar
Thomas Badie committed
736
737
738
739
740
741
742
743
744
745
746
747
748
            // Get all the variable in the signature.
            bdd sup_sig = bdd_support(sig);

            // Get the variable in the signature which represents the
            // conditions.
            bdd sup_all_atomic_prop = bdd_exist(sup_sig, nonapvars);

            // Get the part of the signature composed only with the atomic
            // proposition.
            bdd all_atomic_prop = bdd_exist(sig, nonapvars);

	    // First loop over all possible valuations atomic properties.
            while (all_atomic_prop != bddfalse)
749
750
751
752
753
754
	      {
		bdd one = bdd_satoneset(all_atomic_prop,
					sup_all_atomic_prop,
					bddtrue);
		all_atomic_prop -= one;

755
		// For each possible valuation, iterate over all possible
756
757
758
759
760
761
762
763
764
		// destination classes.   We use minato_isop here, because
		// if the same valuation of atomic properties can go
		// to two different classes C1 and C2, iterating on
		// C1 + C2 with the above bdd_satoneset loop will see
		// C1 then (!C1)C2, instead of C1 then C2.
		// With minatop_isop, we ensure that the no negative
		// class variable will be seen (likewise for promises).
		minato_isop isop(sig & one);

Thomas Badie's avatar
Thomas Badie committed
765
766
                ++nb_satoneset;

767
768
769
		bdd cond_acc_dest;
		while ((cond_acc_dest = isop.next()) != bddfalse)
		  {
770
771
                    ++stat.transitions;

Thomas Badie's avatar
Thomas Badie committed
772
773
                    ++nb_minato;

774
775
776
777
778
779
780
781
		    // Take the transition, and keep only the variable which
		    // are used to represent the class.
		    bdd dest = bdd_existcomp(cond_acc_dest,
					     all_class_var_);

		    // Keep only ones who are acceptance condition.
		    bdd acc = bdd_existcomp(cond_acc_dest, sup_all_acc);

782
		    // Keep the other!
783
784
785
786
		    bdd cond = bdd_existcomp(cond_acc_dest,
					     sup_all_atomic_prop);

		    // Because we have complemented all the acceptance
787
788
		    // conditions on the input automaton, we must
		    // revert them to create a new transition.
789
790
791
792
793
794
		    acc = reverser.reverse_complement(acc);

		    // Take the id of the source and destination.  To
		    // know the source, we must take a random state in
		    // the list which is in the class we currently
		    // work on.
795
796
		    int src = bdd2state[previous_class_
					[a_->state_number(*p.second.begin())]];
797
798
		    int dst = bdd2state[dest];

Thomas Badie's avatar
Thomas Badie committed
799
800
801
                    if (Cosimulation)
                      std::swap(src, dst);

802
803
804
805
806
807
808
809
		    // src or dst == 0 means "dest" or "prev..." isn't
		    // in the map.  so it is a bug.
		    assert(src != 0);
		    assert(dst != 0);

		    // Create the transition, add the condition and the
		    // acceptance condition.
		    tgba_explicit_number::transition* t
810
811
812
813
814
815
		      = res->create_transition(src, dst);
		    t->condition = cond;
		    if (Sba && Cosimulation)
		      accst[dst] = acc;
		    else
		      t->acceptance_conditions = acc;
816
817
		  }
	      }
Thomas Badie's avatar
Thomas Badie committed
818
819
          }

820
	res->set_init_state(bdd2state[previous_class_
821
				      [a_->get_init_state_number()]]);
Thomas Badie's avatar
Thomas Badie committed
822

823
	res->merge_transitions();
Thomas Badie's avatar
Thomas Badie committed
824

825
826
827
828
829
830
831
	// Mark all accepting state in a second pass, when
	// dealing with SBA in cosimulation.
	if (Sba && Cosimulation)
	  for (unsigned snum = current_max; snum > 0; --snum)
	    {
	      const state* s = res->get_state(snum);
	      bdd acc = accst[snum];
832
	      for (auto it: res->succ(s))
833
834
835
836
837
838
839
		{
		  tgba_explicit_number::transition* t =
		    res->get_transition(it);
		  t->acceptance_conditions = acc;
		}
	    }

Thomas Badie's avatar
Thomas Badie committed
840
841
        res_is_deterministic = nb_minato == nb_satoneset;

842
843
844
845
846
847
848
849
850
851
852
	return res;
      }


      // Debug:
      // In a first time, print the signature, and the print a list
      // of each state in this partition.
      // In a second time, print foreach state, who is where,
      // where is the new class name.
      void print_partition()
      {
853
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
854
855
          {
            std::cerr << "partition: "
856
                      << bdd_format_isop(a_->get_dict(), p.first)
Thomas Badie's avatar
Thomas Badie committed
857
                      << std::endl;
858
859
            for (auto s: p.second)
	      std::cerr << "  - " << a_->format_state(s) << '\n';
Thomas Badie's avatar
Thomas Badie committed
860
861
          }

862
	std::cerr << "\nPrevious iteration\n" << std::endl;
Thomas Badie's avatar
Thomas Badie committed
863

864
865
	unsigned ps = previous_class_.size();
	for (unsigned p = 0; p < ps; ++p)
Thomas Badie's avatar
Thomas Badie committed
866
          {
867
            std::cerr << a_->format_state(a_->state_from_number(p))
Thomas Badie's avatar
Thomas Badie committed
868
                      << " was in "
869
                      << bdd_format_set(a_->get_dict(), previous_class_[p])
870
                      << '\n';
Thomas Badie's avatar
Thomas Badie committed
871
          }
872
      }
Thomas Badie's avatar
Thomas Badie committed
873

Thomas Badie's avatar
Thomas Badie committed
874
    protected:
875
      // The automaton which is simulated.
876
877
      tgba_digraph* a_;
      tgba_digraph* old_a_;
Thomas Badie's avatar
Thomas Badie committed
878

879
880
881
882
883
884
885
      // Relation is aimed to represent the same thing than
      // rel_. The difference is in the way it does.
      // If A => A /\ A => B, rel will be (!A U B), but relation_
      // will have A /\ B at the key A. This trick is due to a problem
      // with the computation of the resulting automaton with the signature.
      // rel_ will pollute the meaning of the signature.
      map_bdd_bdd relation_;
Thomas Badie's avatar
Thomas Badie committed
886

887
      // Represent the class of each state at the previous iteration.
888
      vector_state_bdd previous_class_;
Thomas Badie's avatar
Thomas Badie committed
889

890
891
892
      // The list of state for each class at the current_iteration.
      // Computed in `update_sig'.
      map_bdd_lstate bdd_lstate_;
Thomas Badie's avatar
Thomas Badie committed
893

894
895
896
      // The queue of free bdd. They will be used as the identifier
      // for the class.
      std::queue<int> free_var_;
Thomas Badie's avatar
Thomas Badie committed
897

898
899
      // The list of used bdd. They are in used as identifier for class.
      std::list<bdd> used_var_;
Thomas Badie's avatar
Thomas Badie committed
900

901
902
      // Size of the automaton.
      unsigned int size_a_;
Thomas Badie's avatar
Thomas Badie committed
903

904
905
906
      // Used to know when there is no evolution in the po. Updated
      // in the `update_po' method.
      unsigned int po_size_;
Thomas Badie's avatar
Thomas Badie committed
907

908
909
      // All the class variable:
      bdd all_class_var_;
Thomas Badie's avatar
Thomas Badie committed
910
911
912
913
914
915
916

      // The flag to say if the outgoing state is initial or not
      bdd bdd_initial;

      // Initial state of the automaton we are working on
      state* initial_state;

Thomas Badie's avatar
Thomas Badie committed
917
918
      bdd all_proms_;

919
      automaton_size stat;
920

Thomas Badie's avatar
Thomas Badie committed
921
      scc_map* scc_map_;
922
      vector_state_state old_name_;
Thomas Badie's avatar
Thomas Badie committed
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
      map_state_state new_original_;

      // This table link a state in the current automaton with a state
      // in the original one.
      map_state_state old_old_name_;

      const map_constraint* map_cst_;

      const tgba* original_;

      bdd all_acceptance_conditions_;

      // This variable is used when we return the copy, so we avoid
      // deleting what we return. It is better!
      bool dont_delete_old_;

      bool res_is_deterministic;
    };

    // For now, we don't try to handle cosimulation.
943
    class direct_simulation_dont_care: public direct_simulation<false, false>
Thomas Badie's avatar
Thomas Badie committed
944
945
946
947
948
949
950
951
952
953
954
955
    {
      typedef std::vector<std::list<constraint> > constraints;
      typedef std::map<bdd,                  // Source Class.
                       std::map<bdd,         // Destination (implied) Class.
                                std::list<constraint>, // Constraints list.
                                bdd_less_than>,
                       bdd_less_than> constraint_list;
      typedef std::list<std::pair<bdd, bdd> > list_bdd_bdd;


    public:
      direct_simulation_dont_care(const tgba* t)
956
      : direct_simulation<false, false>(t)
Thomas Badie's avatar
Thomas Badie committed
957
958
959
      {
        // This variable is used in the new signature.
        on_cycle_ =
960
          bdd_ithvar(a_->get_dict()->register_anonymous_variables(1, this));
Thomas Badie's avatar
Thomas Badie committed
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983

        // This one is used for the iteration on all the
        // possibilities. Avoid computing two times "no constraints".
        empty_seen_ = false;


        // If this variable is set to true, we have a number limit of
        // simulation to run.
        has_limit_ = false;

	notap = (bdd_support(all_acceptance_conditions_)
                 & all_class_var_ & on_cycle_);
      }

      // This function computes the don't care signature of the state
      // src. This signature is similar to the classic one, excepts
      // that if the transition is on a SCC, we add a on_cycle_ on it,
      // otherwise we add !on_cycle_. This allows us to split the
      // signature later.
      bdd dont_care_compute_sig(const state* src)
      {
        bdd res = bddfalse;

984
        unsigned scc = scc_map_->scc_of_state(old_name_[a_->state_number(src)]);
Thomas Badie's avatar
Thomas Badie committed
985
986
        bool sccacc = scc_map_->accepting(scc);

987
	for (auto sit: a_->succ(src))
Thomas Badie's avatar
Thomas Badie committed
988
989
          {
            const state* dst = sit->current_state();
990
            bdd cl = previous_class_[a_->state_number(dst)];
Thomas Badie's avatar
Thomas Badie committed
991
992
            bdd acc;

993
            if (scc != scc_map_->scc_of_state(old_name_[a_->state_number(dst)]))
Thomas Badie's avatar
Thomas Badie committed
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
              acc = !on_cycle_;
            else if (sccacc)
              acc = on_cycle_ & sit->current_acceptance_conditions();
            else
              acc = on_cycle_ & all_proms_;

            bdd to_add = acc & sit->current_condition() & relation_[cl];
            res |= to_add;
          }
        return res;
      }

      // We used to have
      //   sig(s1) = (f1 | g1)
      //   sig(s2) = (f2 | g2)
      // and we say that s2 simulates s1 if sig(s1)=>sig(s2).
      // This amount to testing whether (f1|g1)=>(f2|g2),
      // which is equivalent to testing both
      //    f1=>(f2|g2)  and g1=>(f2|g2)
      // separately.
      //
      // Now we have a slightly improved version of this rule.
      // g1 and g2 are not on cycle, so they can make as many
      // promises as we wish, if that helps.  Adding promises
      // to g2 will not help, but adding promises to g1 can.
      //
      // So we test whether
      //    f1=>(f2|g2)
      //    g1=>noprom(f2|g2)
      // Where noprom(f2|g2) removes all promises from f2|g2.
      // (g1 do not have promises, and neither do g2).

      bool could_imply_aux(bdd f1, bdd g1, bdd left_class,
			   bdd right, bdd right_class)
      {
        (void) left_class;
        (void) right_class;

        bdd f2g2 = bdd_exist(right, on_cycle_);
        bdd f2g2n = bdd_exist(f2g2, all_proms_);

	bdd both = left_class & right_class;
	int lc = bdd_var(left_class);
        f1 = bdd_compose(f1, both, lc);
        g1 = bdd_compose(g1, both, lc);
        f2g2 = bdd_compose(f2g2, both, lc);
        f2g2n = bdd_compose(f2g2n, both, lc);

        return bdd_implies(f1, f2g2) && bdd_implies(g1, f2g2n);
      }

      bool could_imply(bdd left, bdd left_class,
		       bdd right, bdd right_class)
      {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1048
1049
1050
1051
1052
	bdd f1 = bdd_relprod(left, on_cycle_, on_cycle_);
	bdd g1 = bdd_relprod(left, !on_cycle_, on_cycle_);

        //bdd f1 = bdd_restrict(left, on_cycle_);
        //bdd g1 = bdd_restrict(left, !on_cycle_);
Thomas Badie's avatar
Thomas Badie committed
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
	return could_imply_aux(f1, g1, left_class,
			       right, right_class);
      }

      void dont_care_update_po(const list_bdd_bdd& now_to_next,
                               map_bdd_bdd& relation)
      {
        // This loop follows the pattern given by the paper.
        // foreach class do
        // |  foreach class do
        // |  | update po if needed
        // |  od
        // od

        for (list_bdd_bdd::const_iterator it1 = now_to_next.begin();
             it1 != now_to_next.end();
             ++it1)
          {
            bdd accu = it1->second;

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1073
1074
1075
1076
1077
	    bdd f1 = bdd_relprod(it1->first, on_cycle_, on_cycle_);
	    bdd g1 = bdd_relprod(it1->first, !on_cycle_, on_cycle_);

            // bdd f1 = bdd_restrict(it1->first_, on_cycle_);
            // bdd g1 = bdd_restrict(it1->first_, !on_cycle_);
Thomas Badie's avatar
Thomas Badie committed
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101

            for (list_bdd_bdd::const_iterator it2 = now_to_next.begin();
                 it2 != now_to_next.end();
                 ++it2)
              {
                // Skip the case managed by the initialization of accu.
                if (it1 == it2)
                  continue;

		if (could_imply_aux(f1, g1, it1->second,
				    it2->first, it2->second))
                  {
                    accu &= it2->second;
                    ++po_size_;
                  }
              }
            relation[it1->second] = accu;
          }
      }

#define ISOP(bdd) #bdd" - " << bdd_format_isop(a_->get_dict(), bdd)

      inline bool is_out_scc(bdd b)
      {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1102
1103
	return bddfalse !=  bdd_relprod(b, !on_cycle_, on_cycle_);
        // return bddfalse != bdd_restrict(b, !on_cycle_);
Thomas Badie's avatar
Thomas Badie committed
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
      }

      // This method solves three kind of problems, where we have two
      // conjunctions of variable (that corresponds to a particular
      // transition), and where left could imply right.
      // Three cases:
      //   - αP₁ ⇒ xβP₁ where x is unknown.
      //   - xβP₁ ⇒ αP₁ where x is unknown.
      //   - xαP₁ ⇒ yβP₁ where x, y are unknown.
      void create_simple_constraint(bdd left, bdd right,
                                    const state* src_left,
                                    const state* src_right,
                                    std::list<constraint>& constraint)
      {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1118
	assert(src_left != src_right);
Thomas Badie's avatar
Thomas Badie committed
1119
1120
1121
1122
1123
1124
1125
1126
1127
        // Determine which is the current case.
        bool out_scc_left = is_out_scc(left);
        bool out_scc_right = is_out_scc(right);
        bdd dest_class = bdd_existcomp(left, all_class_var_);
        assert(revert_relation_.find(dest_class) != revert_relation_.end());
        const state* dst_left = revert_relation_[dest_class];
        dest_class = bdd_existcomp(right, all_class_var_);
        const state* dst_right = revert_relation_[dest_class];

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1128
1129
	assert(src_left != dst_left || src_right != dst_right);

Thomas Badie's avatar
Thomas Badie committed
1130
1131
1132
        left = bdd_exist(left, all_class_var_ & on_cycle_);
        right = bdd_exist(right, all_class_var_ & on_cycle_);

1133
1134
1135
1136
1137
	unsigned src_left_n = a_->state_number(src_left);
	unsigned src_right_n = a_->state_number(src_right);
	unsigned dst_left_n = a_->state_number(dst_left);
	unsigned dst_right_n = a_->state_number(dst_right);

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1138

Thomas Badie's avatar
Thomas Badie committed
1139
1140
1141
1142
1143
1144
1145
1146
        if (!out_scc_left && out_scc_right)
          {
            bdd b = bdd_exist(right, notap);
            bdd add = bdd_exist(left & b, bdd_support(b));

            if (add != bddfalse
                && bdd_exist(add, all_acceptance_conditions_) == bddtrue)
              {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1147
1148
		assert(src_right != dst_right);

1149
1150
                constraint.emplace_back(new_original_[old_name_[src_right_n]],
					new_original_ [old_name_[dst_right_n]],
1151
					add);
Thomas Badie's avatar
Thomas Badie committed
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
              }
          }
        else if (out_scc_left && !out_scc_right)
          {
            bdd b = bdd_exist(left, notap);
            bdd add = bdd_exist(right & b, bdd_support(b));

            if (add != bddfalse
                && bdd_exist(add, all_acceptance_conditions_) == bddtrue)
              {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1162
1163
		assert(src_left != dst_left);

1164
1165
                constraint.emplace_back(new_original_[old_name_[src_left_n]],
					new_original_[old_name_[dst_left_n]],
1166
					add);
Thomas Badie's avatar
Thomas Badie committed
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
              }
          }
        else if (out_scc_left && out_scc_right)
          {
            bdd b = bdd_exist(left, notap);
            bdd add = bdd_exist(right & b, bdd_support(b));

            if (add != bddfalse
                && bdd_exist(add, all_acceptance_conditions_) == bddtrue)
              {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1177
		assert(src_left != dst_left && src_right != dst_right);
Thomas Badie's avatar
Thomas Badie committed
1178
		// FIXME: cas pas compris.
1179
1180
                constraint.emplace_back(new_original_[old_name_[src_left_n]],
					new_original_[old_name_[dst_left_n]],
1181
					add);
1182
1183
		constraint.emplace_back(new_original_[old_name_[src_right_n]],
					new_original_[old_name_[dst_right_n]],
1184
					add);
Thomas Badie's avatar
Thomas Badie committed
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
              }

          }
        else
          assert(0);
      }


      // This function run over the signatures, and select the
      // transitions that are out of a SCC and call the function
      // create_simple_constraint to solve the problem.

      // NOTE: Currently, this may not be the most accurate method,
      // because we check for equality in the destination part of the
      // signature. We may just check the destination that can be
      // implied instead.
      std::list<constraint> create_new_constraint(const state* left,
                                                  const state* right,
                                                  map_state_bdd& state2sig)
      {
1205
1206
	bdd pcl = previous_class_[a_->state_number(left)];
	bdd pcr = previous_class_[a_->state_number(right)];
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1207

Thomas Badie's avatar
Thomas Badie committed
1208
1209
1210
1211
1212
        bdd sigl = state2sig[left];
        bdd sigr = state2sig[right];

        std::list<constraint> res;

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1213
1214
1215
1216
1217
1218
	bdd ex = all_class_var_ & on_cycle_;

	bdd both = pcl & pcr;
	int lc = bdd_var(pcl);
#define DEST(x) bdd_compose(bdd_existcomp(x, ex), both, lc)

Thomas Badie's avatar
Thomas Badie committed
1219
1220
        // Key is destination class, value is the signature part that
        // led to this destination class.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
	map_bdd_bdd sigl_map;
	{
	  minato_isop isop(sigl & on_cycle_);
	  bdd cond_acc_dest;
	  while ((cond_acc_dest = isop.next()) != bddfalse)
	    sigl_map[DEST(cond_acc_dest)]
	      |= cond_acc_dest;
	}
	{
	  minato_isop isop(sigl & !on_cycle_);
	  bdd cond_acc_dest;
	  while ((cond_acc_dest = isop.next()) != bddfalse)
	    sigl_map[DEST(cond_acc_dest)]
	      |= cond_acc_dest;
	}
Thomas Badie's avatar
Thomas Badie committed
1236
        map_bdd_bdd sigr_map;
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
	{
	  minato_isop isop2(sigr & on_cycle_);
	  bdd cond_acc_dest2;
	  while ((cond_acc_dest2 = isop2.next()) != bddfalse)
	    sigr_map[DEST(cond_acc_dest2)]
	      |= cond_acc_dest2;
	}
	{
	  minato_isop isop2(sigr & !on_cycle_);
	  bdd cond_acc_dest2;
	  while ((cond_acc_dest2 = isop2.next()) != bddfalse)
	    sigr_map[DEST(cond_acc_dest2)]
	      |= cond_acc_dest2;
	}
Thomas Badie's avatar
Thomas Badie committed
1251
1252

        // Iterate over the transitions of both states.
1253
1254
1255
1256
1257
1258
1259
1260
1261
        for (auto lp: sigl_map)
	  for (auto rp: sigr_map)
	    // And create constraints if any of the transitions
	    // is out of the SCC and the left could imply the right.
	    if ((is_out_scc(lp.second) || is_out_scc(rp.second))
		&& (bdd_exist(lp.first, on_cycle_) ==
		    bdd_exist(rp.first, on_cycle_)))
	      create_simple_constraint(lp.second, rp.second,
				       left, right, res);
Thomas Badie's avatar
Thomas Badie committed
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
        return res;
      }

      inline automaton_size get_stat() const
      {
        return min_size_;
      }

      tgba* run()
      {
        // Iterate the simulation until the end. We just don't return
        // an automaton. This allows us to get all the information
        // about the states and their signature.
        main_loop();

        // Compute the don't care signatures,
        map_bdd_lstate dont_care_bdd_lstate;
        // Useful to keep track of who is who.
        map_state_bdd dont_care_state2sig;
        map_state_bdd state2sig;

        list_bdd_bdd dont_care_now_to_now;
        map_bdd_state class2state;
1285
1286
1287
        list_bdd_bdd now_to_now;
        bdd_lstate_.clear();

Thomas Badie's avatar
Thomas Badie committed
1288
        // Compute the don't care signature for all the states.
1289
	for (unsigned s = 0; s < size_a_; ++s)
Thomas Badie's avatar
Thomas Badie committed
1290
          {
1291
1292
	    const state* src = a_->state_from_number(s);
	    bdd clas = previous_class_[s];
Thomas Badie's avatar
Thomas Badie committed
1293
1294
1295
            bdd sig = dont_care_compute_sig(src);
            dont_care_bdd_lstate[sig].push_back(src);
            dont_care_state2sig[src] = sig;
1296
1297
            dont_care_now_to_now.emplace_back(sig, clas);
            class2state[clas] = src;
Thomas Badie's avatar
Thomas Badie committed
1298

1299
            sig = compute_sig(src);
Thomas Badie's avatar
Thomas Badie committed
1300
1301
            bdd_lstate_[sig].push_back(src);
            state2sig[src] = sig;
1302
            now_to_now.push_back(std::make_pair(sig, clas));
Thomas Badie's avatar
Thomas Badie committed
1303
1304
1305
1306
1307
1308
1309
1310
1311
          }

        map_bdd_bdd dont_care_relation;
        map_bdd_bdd relation;
        update_po(now_to_now, relation);
        dont_care_update_po(dont_care_now_to_now, dont_care_relation);

        constraint_list cc;

1312
1313
        for (auto p: relation)
	  revert_relation_[p.second] = class2state[p.first];
Thomas Badie's avatar
Thomas Badie committed
1314
1315
1316
1317
1318

        int number_constraints = 0;
        relation_ = relation;


1319
1320
1321
        // make the diff between the two tables: imply and
        // could_imply.
	for (unsigned s = 0; s < size_a_; ++s)
Thomas Badie's avatar
Thomas Badie committed
1322
          {
1323
1324
1325
            bdd clas = previous_class_[s];
            assert(relation.find(clas) != relation.end());
            assert(dont_care_relation.find(clas) != dont_care_relation.end());
Thomas Badie's avatar
Thomas Badie committed
1326

1327
1328
            bdd care_rel = relation[clas];
            bdd dont_care_rel = dont_care_relation[clas];
Thomas Badie's avatar
Thomas Badie committed
1329
1330
1331
1332

            if (care_rel == dont_care_rel)
              continue;

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1333
1334
            // If they are different we necessarily have
	    // dont_care_rel == care_rel & diff
Thomas Badie's avatar
Thomas Badie committed
1335
            bdd diff = bdd_exist(dont_care_rel, care_rel);
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1336
1337
	    assert(dont_care_rel == (care_rel & diff));
	    assert(diff != bddtrue);
Thomas Badie's avatar
Thomas Badie committed
1338

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1339
	    do
Thomas Badie's avatar
Thomas Badie committed
1340
              {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1341
                bdd cur_diff = bdd_ithvar(bdd_var(diff));
1342
1343
                cc[clas][cur_diff]
                  = create_new_constraint(a_->state_from_number(s),
Thomas Badie's avatar
Thomas Badie committed
1344
1345
1346
                                          class2state[cur_diff],
                                          dont_care_state2sig);
                ++</