simulation.cc 23 KB
Newer Older
Thomas Badie's avatar
Thomas Badie committed
1
// -*- coding: utf-8 -*-
2
3
// Copyright (C) 2012, 2013, 2014, 2015 Laboratoire de Recherche et
// Développement 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
27
28
#include "simulation.hh"
#include "misc/minato.hh"
#include "tgba/bddprint.hh"
#include "tgbaalgos/reachiter.hh"
29
#include "tgbaalgos/sccfilter.hh"
30
#include "tgbaalgos/sccinfo.hh"
31
#include "misc/bddlt.hh"
Thomas Badie's avatar
Thomas Badie committed
32
33
34
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

// 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'.
64
// 3. Rename the class (to actualize the name in the previous_class and
Thomas Badie's avatar
Thomas Badie committed
65
66
67
68
69
70
71
72
//    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.
//
73
// Obviously these functions are possibly cut into several little ones.
Thomas Badie's avatar
Thomas Badie committed
74
75
// This is just the general development idea.

Thomas Badie's avatar
Thomas Badie committed
76

Thomas Badie's avatar
Thomas Badie committed
77
78
79
80
81
82
83
namespace spot
{
  namespace
  {
    // Some useful typedef:

    // Used to get the signature of the state.
84
    typedef std::vector<bdd> vector_state_bdd;
Thomas Badie's avatar
Thomas Badie committed
85
86

    // Get the list of state for each class.
87
    typedef std::map<bdd, std::list<unsigned>,
Thomas Badie's avatar
Thomas Badie committed
88
89
                     bdd_less_than> map_bdd_lstate;

90
    typedef std::map<bdd, unsigned, bdd_less_than> map_bdd_state;
Thomas Badie's avatar
Thomas Badie committed
91
92
93
94


    // This class helps to compare two automata in term of
    // size.
95
96
97
98
99
100
101
102
    struct automaton_size
    {
      automaton_size()
        : transitions(0),
          states(0)
      {
      }

103
104
105
106
107
108
109
110
111
112
113
114
      automaton_size(const tgba_digraph_ptr& a)
        : transitions(a->num_transitions()),
          states(a->num_states())
      {
      }

      void set_size(const tgba_digraph_ptr& a)
      {
	states = a->num_states();
	transitions = a->num_transitions();
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
115
      inline bool operator!=(const automaton_size& r)
116
117
118
119
      {
        return transitions != r.transitions || states != r.states;
      }

Thomas Badie's avatar
Thomas Badie committed
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
      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;
      }

150
151
152
      int transitions;
      int states;
    };
Thomas Badie's avatar
Thomas Badie committed
153

Thomas Badie's avatar
Thomas Badie committed
154
    // The direct_simulation. If Cosimulation is true, we are doing a
155
156
    // cosimulation.
    template <bool Cosimulation, bool Sba>
157
    class direct_simulation
Thomas Badie's avatar
Thomas Badie committed
158
    {
Thomas Badie's avatar
Thomas Badie committed
159
    protected:
160
161
      // Shortcut used in update_po and go_to_next_it.
      typedef std::map<bdd, bdd, bdd_less_than> map_bdd_bdd;
162
      int acc_vars;
163
    public:
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185

      bdd mark_to_bdd(acc_cond::mark_t m)
      {
	// FIXME: Use a cache.
	bdd res = bddtrue;
	for (auto n: a_->acc().sets(m))
	  res &= bdd_ithvar(acc_vars + n);
	return res;
      }

      acc_cond::mark_t bdd_to_mark(const tgba_digraph_ptr& aut, bdd b)
      {
	// FIXME: Use a cache.
	std::vector<unsigned> res;
	while (b != bddtrue)
	  {
	    res.push_back(bdd_var(b) - acc_vars);
	    b = bdd_high(b);
	  }
	return aut->acc().marks(res.begin(), res.end());
      }

186
187
      direct_simulation(const const_tgba_digraph_ptr& in)
        : po_size_(0),
Thomas Badie's avatar
Thomas Badie committed
188
          all_class_var_(bddtrue),
189
          original_(in)
190
      {
191
192
193
194
	if (in->acc().uses_fin_acceptance())
	  throw std::runtime_error
	    ("direct_simulation() does not yet support Fin acceptance");

195
196
197
198
199
200
201
202
	// Call get_init_state_number() before anything else as it
	// might add a state.
	unsigned init_state_number = in->get_init_state_number();
        scc_info_.reset(new scc_info(in));

	unsigned ns = in->num_states();
	assert(ns > 0);
	size_a_ = ns;
Thomas Badie's avatar
Thomas Badie committed
203

204
205
	// Replace all the acceptance conditions by their complements.
	// (In the case of Cosimulation, we also flip the transitions.)
206
207
208
209
210
	if (Cosimulation)
	  {
	    a_ = make_tgba_digraph(in->get_dict());
	    a_->copy_ap_of(in);
	    a_->copy_acceptance_conditions_of(in);
211
	    a_->new_states(ns);
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
	    auto& acccond = in->acc();

	    for (unsigned s = 0; s < ns; ++s)
	      {
		for (auto& t: in->out(s))
		  {
		    acc_cond::mark_t acc;
		    if (Sba)
		      {
			// 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 arcs
			// (which now become outgoing arcs after
			// transposition).
			acc = 0U;
			for (auto& td: in->out(t.dst))
			  {
			    acc = acccond.comp(td.acc);
			    break;
			  }
		      }
		    else
		      {
			acc = acccond.comp(t.acc);
		      }
238
		    a_->new_transition(t.dst, s, t.cond, acc);
239
240
241
242
243
244
245
246
247
248
249
250
		  }
		a_->set_init_state(init_state_number);
	      }
	  }
	else
	  {
	    a_ = make_tgba_digraph(in, tgba::prop_set::all());
	    auto& acccond = a_->acc();
	    for (auto& t: a_->transitions())
	      t.acc = acccond.comp(t.acc);
	  }
	assert(a_->num_states() == size_a_);
251
252
253
254
255

	// 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()
256
	  ->register_anonymous_variables(size_a_ + 1, this);
257

258
259
260
261
262
263
264
	unsigned n_acc = a_->acc().num_sets();
	acc_vars = a_->get_dict()
	  ->register_anonymous_variables(n_acc, this);

	all_proms_ = bddtrue;
	for (unsigned v = acc_vars; v < acc_vars + n_acc; ++v)
	  all_proms_ &= bdd_ithvar(v);
Thomas Badie's avatar
Thomas Badie committed
265

Thomas Badie's avatar
Thomas Badie committed
266
267
        bdd_initial = bdd_ithvar(set_num++);
	bdd init = bdd_ithvar(set_num++);
268
269
270

	used_var_.push_back(init);

271
272
273
274
	// 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
275

276
277
278
279
	// 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.
280
	all_class_var_ = init;
281
	for (unsigned i = set_num; i < set_num + size_a_ - 1; ++i)
Thomas Badie's avatar
Thomas Badie committed
282
283
284
285
286
          {
            free_var_.push(i);
            all_class_var_ &= bdd_ithvar(i);
          }

287
288
	relation_[init] = init;
      }
Thomas Badie's avatar
Thomas Badie committed
289
290


291
292
293
      // 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
294
      virtual ~direct_simulation()
295
      {
296
	a_->get_dict()->unregister_all_my_variables(this);
297
      }
Thomas Badie's avatar
Thomas Badie committed
298

299
      // Update the name of the classes.
300
301
302
303
304
305
      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.
306
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
307
          {
308
309
310
311
312
313
314
315
	    // 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)
316
		previous_class_[s] = bddfalse;
317
318
	    else
	      for (auto s: p.second)
319
		previous_class_[s] = *it_bdd;
320
	    ++it_bdd;
Thomas Badie's avatar
Thomas Badie committed
321
          }
322
323
      }

Thomas Badie's avatar
Thomas Badie committed
324
      void main_loop()
325
326
327
328
329
      {
	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
330
          {
331
            update_previous_class();
Thomas Badie's avatar
Thomas Badie committed
332
333
334
335
336
337
338
339
            nb_partition_before = bdd_lstate_.size();
            bdd_lstate_.clear();
            nb_po_before = po_size_;
            po_size_ = 0;
            update_sig();
            go_to_next_it();
          }

340
	update_previous_class();
Thomas Badie's avatar
Thomas Badie committed
341
342
343
      }

      // The core loop of the algorithm.
344
      tgba_digraph_ptr run()
Thomas Badie's avatar
Thomas Badie committed
345
346
      {
        main_loop();
347
348
	return build_result();
      }
Thomas Badie's avatar
Thomas Badie committed
349

350
      // Take a state and compute its signature.
351
      bdd compute_sig(unsigned src)
352
      {
Thomas Badie's avatar
Thomas Badie committed
353
        bdd res = bddfalse;
Thomas Badie's avatar
Thomas Badie committed
354

355
        for (auto& t: a_->out(src))
Thomas Badie's avatar
Thomas Badie committed
356
          {
357
            bdd acc = mark_to_bdd(t.acc);
358
359
360
361

	    // 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.
362
	    bdd to_add = acc & t.cond & relation_[previous_class_[t.dst]];
Thomas Badie's avatar
Thomas Badie committed
363

364
365
	    res |= to_add;
	  }
Thomas Badie's avatar
Thomas Badie committed
366

Thomas Badie's avatar
Thomas Badie committed
367
        // When we Cosimulate, we add a special flag to differentiate
368
        // the initial state from the other.
369
        if (Cosimulation && src == a_->get_init_state_number())
Thomas Badie's avatar
Thomas Badie committed
370
371
372
          res |= bdd_initial;

        return res;
373
374
      }

Thomas Badie's avatar
Thomas Badie committed
375

376
377
      void update_sig()
      {
378
	for (unsigned s = 0; s < size_a_; ++s)
379
	  bdd_lstate_[compute_sig(s)].push_back(s);
380
      }
Thomas Badie's avatar
Thomas Badie committed
381
382


383
384
385
386
      // 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
387

Thomas Badie's avatar
Thomas Badie committed
388
389
390

        // If we have created more partitions, we need to use more
        // variables.
391
	for (int i = 0; i < nb_new_color; ++i)
Thomas Badie's avatar
Thomas Badie committed
392
393
394
395
396
397
          {
            assert(!free_var_.empty());
            used_var_.push_back(bdd_ithvar(free_var_.front()));
            free_var_.pop();
          }

Thomas Badie's avatar
Thomas Badie committed
398
399
400

        // If we have reduced the number of partition, we 'free' them
        // in the free_var_ list.
401
402
403
404
405
406
407
408
409
410
411
	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
412

413
414
415
416
417
418
419
	// 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
420

421
	std::list<bdd>::iterator it_bdd = used_var_.begin();
Thomas Badie's avatar
Thomas Badie committed
422

423
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
424
          {
425
426
427
428
429
430
	    // 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.
431
432
433
434
	    bdd acc = bddfalse;
	    if (p.first != bddfalse)
	      acc = *it_bdd;
	    now_to_next[p.first] = acc;
435
	    ++it_bdd;
Thomas Badie's avatar
Thomas Badie committed
436
437
          }

Thomas Badie's avatar
Thomas Badie committed
438
	update_po(now_to_next, relation_);
439
440
      }

Thomas Badie's avatar
Thomas Badie committed
441
442
443
444
445
446
447
448
449
      // 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)
450
451
452
453
454
455
456
457
      {
	// 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
458
459
	for (typename container_bdd_bdd::const_iterator it1
               = now_to_next.begin();
460
461
	     it1 != now_to_next.end();
	     ++it1)
Thomas Badie's avatar
Thomas Badie committed
462
463
          {
            bdd accu = it1->second;
Thomas Badie's avatar
Thomas Badie committed
464
465
            for (typename container_bdd_bdd::const_iterator it2
                   = now_to_next.begin();
Thomas Badie's avatar
Thomas Badie committed
466
467
                 it2 != now_to_next.end();
                 ++it2)
Thomas Badie's avatar
Thomas Badie committed
468
469
470
471
472
473
474
475
476
477
478
              {
                // 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
479
            relation[it1->second] = accu;
Thomas Badie's avatar
Thomas Badie committed
480
          }
481
482
483
      }

      // Build the minimal resulting automaton.
484
      tgba_digraph_ptr build_result()
485
      {
486
	tgba_digraph_ptr res = make_tgba_digraph(a_->get_dict());
487
	res->copy_ap_of(a_);
488
	res->copy_acceptance_conditions_of(a_);
489
	if (Sba)
490
	  res->prop_state_based_acc();
491
492

	// Non atomic propositions variables (= acc and class)
493
	bdd nonapvars = all_proms_ & bdd_support(all_class_var_);
494

495
496
	auto* gb = res->create_namer<int>();

497
	// Create one state per partition.
498
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
499
          {
500
501
502
503
504
            bdd cl = previous_class_[p.second.front()];
	    // A state may be referred to either by
	    // its class, or by all the implied classes.
	    auto s = gb->new_state(cl.id());
	    gb->alias_state(s, relation_[cl].id());
Thomas Badie's avatar
Thomas Badie committed
505
506
          }

507
	// Acceptance of states.  Only used if Sba && Cosimulation.
508
	std::vector<acc_cond::mark_t> accst;
509
	if (Sba && Cosimulation)
510
	  accst.resize(res->num_states(), 0U);
511

512
513
514
        stat.states = bdd_lstate_.size();
        stat.transitions = 0;

Thomas Badie's avatar
Thomas Badie committed
515
516
517
        unsigned nb_satoneset = 0;
        unsigned nb_minato = 0;

518
	// For each class, we will create
519
	// all the transitions between the states.
520
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
521
          {
522
523
524
525
526
	    // All states in p.second have the same class, so just
	    // pick the class of the first one first one.
	    bdd src = previous_class_[p.second.front()];

            // Get the signature to derive successors.
527
            bdd sig = compute_sig(p.second.front());
Thomas Badie's avatar
Thomas Badie committed
528

Thomas Badie's avatar
Thomas Badie committed
529
530
531
            if (Cosimulation)
              sig = bdd_compose(sig, bddfalse, bdd_var(bdd_initial));

Thomas Badie's avatar
Thomas Badie committed
532
533
534
535
536
537
538
539
540
541
542
543
544
            // 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)
545
546
547
548
549
550
	      {
		bdd one = bdd_satoneset(all_atomic_prop,
					sup_all_atomic_prop,
					bddtrue);
		all_atomic_prop -= one;

551
		// For each possible valuation, iterate over all possible
552
553
554
555
556
557
558
559
560
		// 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
561
562
                ++nb_satoneset;

563
564
565
		bdd cond_acc_dest;
		while ((cond_acc_dest = isop.next()) != bddfalse)
		  {
566
567
                    ++stat.transitions;

Thomas Badie's avatar
Thomas Badie committed
568
569
                    ++nb_minato;

570
571
		    // Take the transition, and keep only the variable which
		    // are used to represent the class.
572
		    bdd dst = bdd_existcomp(cond_acc_dest,
573
574
575
					     all_class_var_);

		    // Keep only ones who are acceptance condition.
576
577
		    auto acc = bdd_to_mark(res, bdd_existcomp(cond_acc_dest,
							      all_proms_));
578

579
		    // Keep the other!
580
581
582
583
		    bdd cond = bdd_existcomp(cond_acc_dest,
					     sup_all_atomic_prop);

		    // Because we have complemented all the acceptance
584
585
		    // conditions on the input automaton, we must
		    // revert them to create a new transition.
586
		    acc = res->acc().comp(acc);
587

588
589
590
		    if (Cosimulation)
		      {
			if (Sba)
591
592
593
594
595
596
597
			  {
			    // acc should be attached to src, or rather,
			    // in our transition-based representation)
			    // to all transitions leaving src.  As we
			    // can't do this here, store this in a table
			    // so we can fix it later.
			    accst[gb->get_state(src.id())] = acc;
598
			    acc = 0U;
599
600
			  }
			gb->new_transition(dst.id(), src.id(), cond, acc);
601
		      }
602
		    else
603
604
605
		      {
			gb->new_transition(src.id(), dst.id(), cond, acc);
		      }
606
607
		  }
	      }
Thomas Badie's avatar
Thomas Badie committed
608
609
          }

610
611
	res->set_init_state(gb->get_state(previous_class_
					  [a_->get_init_state_number()].id()));
Thomas Badie's avatar
Thomas Badie committed
612

613
	res->merge_transitions(); // FIXME: is this really needed?
Thomas Badie's avatar
Thomas Badie committed
614

615
616
617
	// Mark all accepting state in a second pass, when
	// dealing with SBA in cosimulation.
	if (Sba && Cosimulation)
618
619
620
621
	  {
	    unsigned ns = res->num_states();
	    for (unsigned s = 0; s < ns; ++s)
	      {
622
623
		acc_cond::mark_t acc = accst[s];
		if (acc == 0U)
624
		  continue;
625
		for (auto& t: res->out(s))
626
627
628
		  t.acc = acc;
	      }
	  }
629

630
631
	res->purge_unreachable_states();

632
	delete gb;
633
	res->prop_copy(original_,
634
		       { false, // state-based acc forced below
635
			 false, // single acc set by set_generalized_buchi
636
637
638
		         true,  // weakness preserved,
			 false, // determinism checked and set below
		       });
639
        if (nb_minato == nb_satoneset && !Cosimulation)
640
641
642
	  res->prop_deterministic();
	if (Sba)
	  res->prop_state_based_acc();
643
644
645
646
647
648
649
650
651
652
653
	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()
      {
654
	for (auto& p: bdd_lstate_)
Thomas Badie's avatar
Thomas Badie committed
655
656
          {
            std::cerr << "partition: "
657
                      << bdd_format_isop(a_->get_dict(), p.first)
Thomas Badie's avatar
Thomas Badie committed
658
                      << std::endl;
659
            for (auto s: p.second)
660
661
662
	      std::cerr << "  - "
			<< a_->format_state(a_->state_from_number(s))
			<< '\n';
Thomas Badie's avatar
Thomas Badie committed
663
664
          }

665
	std::cerr << "\nPrevious iteration\n" << std::endl;
Thomas Badie's avatar
Thomas Badie committed
666

667
668
	unsigned ps = previous_class_.size();
	for (unsigned p = 0; p < ps; ++p)
Thomas Badie's avatar
Thomas Badie committed
669
          {
670
            std::cerr << a_->format_state(a_->state_from_number(p))
Thomas Badie's avatar
Thomas Badie committed
671
                      << " was in "
672
                      << bdd_format_set(a_->get_dict(), previous_class_[p])
673
                      << '\n';
Thomas Badie's avatar
Thomas Badie committed
674
          }
675
      }
Thomas Badie's avatar
Thomas Badie committed
676

Thomas Badie's avatar
Thomas Badie committed
677
    protected:
678
      // The automaton which is simulated.
679
      tgba_digraph_ptr a_;
Thomas Badie's avatar
Thomas Badie committed
680

681
682
683
684
685
686
687
      // 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
688

689
      // Represent the class of each state at the previous iteration.
690
      vector_state_bdd previous_class_;
Thomas Badie's avatar
Thomas Badie committed
691

692
693
694
      // 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
695

696
697
698
      // 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
699

700
701
      // 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
702

703
704
      // Size of the automaton.
      unsigned int size_a_;
Thomas Badie's avatar
Thomas Badie committed
705

706
707
708
      // 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
709

710
711
      // All the class variable:
      bdd all_class_var_;
Thomas Badie's avatar
Thomas Badie committed
712
713
714
715

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

Thomas Badie's avatar
Thomas Badie committed
716
717
      bdd all_proms_;

718
      automaton_size stat;
719

720
      std::unique_ptr<scc_info> scc_info_;
Thomas Badie's avatar
Thomas Badie committed
721

722
      const const_tgba_digraph_ptr& original_;
Thomas Badie's avatar
Thomas Badie committed
723
724
    };

Thomas Badie's avatar
Thomas Badie committed
725
726
  } // End namespace anonymous.

Thomas Badie's avatar
Thomas Badie committed
727

728
  tgba_digraph_ptr
729
  simulation(const const_tgba_digraph_ptr& t)
Thomas Badie's avatar
Thomas Badie committed
730
  {
731
732
733
    direct_simulation<false, false> simul(t);
    return simul.run();
  }
Thomas Badie's avatar
Thomas Badie committed
734

735
  tgba_digraph_ptr
736
  simulation_sba(const const_tgba_digraph_ptr& t)
737
738
  {
    direct_simulation<false, true> simul(t);
Thomas Badie's avatar
Thomas Badie committed
739
740
741
    return simul.run();
  }

742
  tgba_digraph_ptr
743
  cosimulation(const const_tgba_digraph_ptr& t)
Thomas Badie's avatar
Thomas Badie committed
744
  {
745
746
747
    direct_simulation<true, false> simul(t);
    return simul.run();
  }
Thomas Badie's avatar
Thomas Badie committed
748

749
  tgba_digraph_ptr
750
  cosimulation_sba(const const_tgba_digraph_ptr& t)
751
752
  {
    direct_simulation<true, true> simul(t);
Thomas Badie's avatar
Thomas Badie committed
753
754
755
    return simul.run();
  }

756
757

  template<bool Sba>
758
  tgba_digraph_ptr
759
  iterated_simulations_(const const_tgba_digraph_ptr& t)
760
  {
761
    tgba_digraph_ptr res = 0;
762
763
764
765
766
767
    automaton_size prev;
    automaton_size next;

    do
      {
        prev = next;
768
        direct_simulation<false, Sba> simul(res ? res : t);
769
        res = simul.run();
770
        if (res->is_deterministic())
771
	  break;
Thomas Badie's avatar
Thomas Badie committed
772

773
774
        direct_simulation<true, Sba> cosimul(res);
	res = cosimul.run();
775

776
	if (Sba)
777
	  res = scc_filter_states(res);
778
	else
779
	  res = scc_filter(res, false);
780
781

        next.set_size(res);
782
783
784
785
786
      }
    while (prev != next);
    return res;
  }

787
  tgba_digraph_ptr
788
  iterated_simulations(const const_tgba_digraph_ptr& t)
789
790
791
792
  {
    return iterated_simulations_<false>(t);
  }

793
  tgba_digraph_ptr
794
  iterated_simulations_sba(const const_tgba_digraph_ptr& t)
795
796
797
798
  {
    return iterated_simulations_<true>(t);
  }

Thomas Badie's avatar
Thomas Badie committed
799
} // End namespace spot.