acc.hh 29.4 KB
Newer Older
1
// -*- coding: utf-8 -*-
2
3
// Copyright (C) 2014, 2015, 2016 Laboratoire de Recherche et
// Développement de l'Epita.
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
//
// This file is part of Spot, a model checking library.
//
// Spot is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// Spot is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
// or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
// License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

20
#pragma once
21

22
23
24
25
#include <functional>
#include <unordered_map>
#include <sstream>
#include <vector>
26
#include <spot/tl/defaultenv.hh>
27
#include <iostream>
28
29
30

namespace spot
{
31
  class SPOT_API acc_cond
32
33
34
35
36
37
38
39
40
  {
  public:
    struct mark_t
    {
      typedef unsigned value_t;
      value_t id;

      mark_t() = default;

41
      mark_t(value_t id) noexcept
42
        : id(id)
43
44
45
      {
      }

46
      template<class iterator>
47
      mark_t(const iterator& begin, const iterator& end) noexcept
48
      {
49
50
51
        id = 0U;
        for (iterator i = begin; i != end; ++i)
          set(*i);
52
53
      }

54
      mark_t(std::initializer_list<unsigned> vals) noexcept
55
        : mark_t(vals.begin(), vals.end())
56
57
58
      {
      }

59
60
      bool operator==(unsigned o) const
      {
61
62
        assert(o == 0U);
        return id == o;
63
64
65
66
      }

      bool operator!=(unsigned o) const
      {
67
68
        assert(o == 0U);
        return id != o;
69
70
71
72
      }

      bool operator==(mark_t o) const
      {
73
        return id == o.id;
74
75
76
77
      }

      bool operator!=(mark_t o) const
      {
78
        return id != o.id;
79
80
81
82
      }

      bool operator<(mark_t o) const
      {
83
        return id < o.id;
84
85
86
87
      }

      bool operator<=(mark_t o) const
      {
88
        return id <= o.id;
89
90
91
92
      }

      bool operator>(mark_t o) const
      {
93
        return id > o.id;
94
95
96
97
      }

      bool operator>=(mark_t o) const
      {
98
        return id >= o.id;
99
100
101
102
      }

      operator bool() const
      {
103
        return id != 0;
104
105
106
107
      }

      bool has(unsigned u) const
      {
108
        return id & (1U << u);
109
110
111
112
      }

      void set(unsigned u)
      {
113
        id |= (1U << u);
114
115
      }

116
117
      void clear(unsigned u)
      {
118
        id &= ~(1U << u);
119
120
      }

121
122
      mark_t& operator&=(mark_t r)
      {
123
124
        id &= r.id;
        return *this;
125
126
127
128
      }

      mark_t& operator|=(mark_t r)
      {
129
130
        id |= r.id;
        return *this;
131
132
133
134
      }

      mark_t& operator-=(mark_t r)
      {
135
136
        id &= ~r.id;
        return *this;
137
138
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
139
140
      mark_t& operator^=(mark_t r)
      {
141
142
        id ^= r.id;
        return *this;
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
143
144
      }

145
146
      mark_t operator&(mark_t r) const
      {
147
        return id & r.id;
148
149
150
151
      }

      mark_t operator|(mark_t r) const
      {
152
        return id | r.id;
153
154
155
156
      }

      mark_t operator-(mark_t r) const
      {
157
        return id & ~r.id;
158
159
      }

160
161
      mark_t operator~() const
      {
162
        return ~id;
163
164
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
165
166
      mark_t operator^(mark_t r) const
      {
167
        return id ^ r.id;
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
168
169
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
170
      mark_t operator<<(unsigned i) const
171
      {
172
        return id << i;
173
174
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
175
      mark_t& operator<<=(unsigned i)
176
      {
177
178
        id <<= i;
        return *this;
179
180
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
181
      mark_t operator>>(unsigned i) const
182
      {
183
        return id >> i;
184
185
      }

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
186
      mark_t& operator>>=(unsigned i)
187
      {
188
189
        id >>= i;
        return *this;
190
191
      }

192
193
      mark_t strip(mark_t y) const
      {
194
195
196
197
198
        // strip every bit of id that is marked in y
        //       100101110100.strip(
        //       001011001000)
        //   ==  10 1  11 100
        //   ==      10111100
199

200
201
        auto xv = id;                // 100101110100
        auto yv = y.id;                // 001011001000
202

203
204
205
206
207
208
209
210
211
212
        while (yv && xv)
          {
            // Mask for everything after the last 1 in y
            auto rm = (~yv) & (yv - 1);        // 000000000111
            // Mask for everything before the last 1 in y
            auto lm = ~(yv ^ (yv - 1));        // 111111110000
            xv = ((xv & lm) >> 1) | (xv & rm);
            yv = (yv & lm) >> 1;
          }
        return xv;
213
214
      }

215
216
217
218
      // Number of bits sets.
      unsigned count() const
      {
#ifdef __GNUC__
219
        return __builtin_popcount(id);
220
#else
221
222
223
224
225
226
227
228
        unsigned c = 0U;
        auto v = id;
        while (v)
          {
            ++c;
            v &= v - 1;
          }
        return c;
229
230
231
#endif
      }

232
233
234
235
236
      // Return the number of the highest set used plus one.
      // So if no set is used, this returns 0,
      // but if the sets {1,3,8} are used, this returns 9.
      unsigned max_set() const
      {
237
238
239
240
241
242
243
244
        auto i = id;
        int res = 0;
        while (i)
          {
            ++res;
            i >>= 1;
          }
        return res;
245
246
      }

247
248
249
      // Return the lowest acceptance mark
      mark_t lowest() const
      {
250
        return id & -id;
251
252
      }

253
254
255
      // Remove n bits that where set
      mark_t& remove_some(unsigned n)
      {
256
257
258
        while (n--)
          id &= id - 1;
        return *this;
259
260
      }

261
262
      template<class iterator>
      void fill(iterator here) const
263
      {
264
265
266
267
268
269
270
271
272
        auto a = id;
        unsigned level = 0;
        while (a)
          {
            if (a & 1)
              *here++ = level;
            ++level;
            a >>= 1;
          }
273
274
275
276
277
      }

      // FIXME: Return some iterable object without building a vector.
      std::vector<unsigned> sets() const
      {
278
279
280
        std::vector<unsigned> res;
        fill(std::back_inserter(res));
        return res;
281
282
283
284
285
286
287
      }

      SPOT_API
      friend std::ostream& operator<<(std::ostream& os, mark_t m);
    };

    // This encodes either an operator or set of acceptance sets.
288
    enum class acc_op : unsigned short
289
290
291
292
293
    { Inf, Fin, InfNeg, FinNeg, And, Or };
    union acc_word
    {
      mark_t mark;
      struct {
294
295
296
        acc_op op;             // Operator
        unsigned short size; // Size of the subtree (number of acc_word),
                             // not counting this node.
297
298
299
      };
    };

300
    struct SPOT_API acc_code: public std::vector<acc_word>
301
    {
302
      bool operator==(const acc_code& other) const
303
      {
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
        unsigned pos = size();
        if (other.size() != pos)
          return false;
        while (pos > 0)
          {
            auto op = (*this)[pos - 1].op;
            auto sz = (*this)[pos - 1].size;
            if (other[pos - 1].op != op ||
                other[pos - 1].size != sz)
              return false;
            switch (op)
              {
              case acc_cond::acc_op::And:
              case acc_cond::acc_op::Or:
                --pos;
                break;
              case acc_cond::acc_op::Inf:
              case acc_cond::acc_op::InfNeg:
              case acc_cond::acc_op::Fin:
              case acc_cond::acc_op::FinNeg:
                pos -= 2;
                if (other[pos].mark != (*this)[pos].mark)
                  return false;
                break;
              }
          }
        return true;
331
332
      };

333
334
      bool operator<(const acc_code& other) const
      {
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
        unsigned pos = size();
        auto osize = other.size();
        if (pos < osize)
          return true;
        if (pos > osize)
          return false;
        while (pos > 0)
          {
            auto op = (*this)[pos - 1].op;
            auto oop = other[pos - 1].op;
            if (op < oop)
              return true;
            if (op > oop)
              return false;
            auto sz = (*this)[pos - 1].size;
            auto osz = other[pos - 1].size;
            if (sz < osz)
              return true;
            if (sz > osz)
              return false;
            switch (op)
              {
              case acc_cond::acc_op::And:
              case acc_cond::acc_op::Or:
                --pos;
                break;
              case acc_cond::acc_op::Inf:
              case acc_cond::acc_op::InfNeg:
              case acc_cond::acc_op::Fin:
              case acc_cond::acc_op::FinNeg:
                pos -= 2;
                auto m = (*this)[pos].mark;
                auto om = other[pos].mark;
                if (m < om)
                  return true;
                if (m > om)
                  return false;
                break;
              }
          }
        return false;
376
377
378
379
      }

      bool operator>(const acc_code& other) const
      {
380
        return other < *this;
381
382
383
384
      }

      bool operator<=(const acc_code& other) const
      {
385
        return !(other < *this);
386
387
388
389
      }

      bool operator>=(const acc_code& other) const
      {
390
        return !(*this < other);
391
392
393
      }

      bool operator!=(const acc_code& other) const
394
      {
395
        return !(*this == other);
396
397
      }

398
      bool is_t() const
399
      {
400
401
402
        unsigned s = size();
        return s == 0
          || ((*this)[s - 1].op == acc_op::Inf && (*this)[s - 2].mark == 0U);
403
404
      }

405
      bool is_f() const
406
      {
407
408
409
        unsigned s = size();
        return s > 1
          && (*this)[s - 1].op == acc_op::Fin && (*this)[s - 2].mark == 0U;
410
411
      }

412
413
      static acc_code f()
      {
414
415
416
417
418
419
        acc_code res;
        res.resize(2);
        res[0].mark = 0U;
        res[1].op = acc_op::Fin;
        res[1].size = 1;
        return res;
420
421
422
423
      }

      static acc_code t()
      {
424
        return {};
425
426
427
428
      }

      static acc_code fin(mark_t m)
      {
429
430
431
432
433
434
        acc_code res;
        res.resize(2);
        res[0].mark = m;
        res[1].op = acc_op::Fin;
        res[1].size = 1;
        return res;
435
436
      }

437
438
      static acc_code fin(std::initializer_list<unsigned> vals)
      {
439
        return fin(mark_t(vals));
440
441
      }

442
443
      static acc_code fin_neg(mark_t m)
      {
444
445
446
447
448
449
        acc_code res;
        res.resize(2);
        res[0].mark = m;
        res[1].op = acc_op::FinNeg;
        res[1].size = 1;
        return res;
450
451
      }

452
453
      static acc_code fin_neg(std::initializer_list<unsigned> vals)
      {
454
        return fin_neg(mark_t(vals));
455
456
      }

457
458
      static acc_code inf(mark_t m)
      {
459
460
461
462
463
464
        acc_code res;
        res.resize(2);
        res[0].mark = m;
        res[1].op = acc_op::Inf;
        res[1].size = 1;
        return res;
465
466
      }

467
468
      static acc_code inf(std::initializer_list<unsigned> vals)
      {
469
        return inf(mark_t(vals));
470
471
      }

472
473
      static acc_code inf_neg(mark_t m)
      {
474
475
476
477
478
479
        acc_code res;
        res.resize(2);
        res[0].mark = m;
        res[1].op = acc_op::InfNeg;
        res[1].size = 1;
        return res;
480
481
      }

482
483
      static acc_code inf_neg(std::initializer_list<unsigned> vals)
      {
484
        return inf_neg(mark_t(vals));
485
486
      }

487
488
      static acc_code buchi()
      {
489
        return inf({0});
490
491
492
493
      }

      static acc_code cobuchi()
      {
494
        return fin({0});
495
496
497
498
      }

      static acc_code generalized_buchi(unsigned n)
      {
499
500
501
502
        acc_cond::mark_t m = (1U << n) - 1;
        if (n == 8 * sizeof(mark_t::value_t))
          m = mark_t(-1U);
        return inf(m);
503
504
505
506
      }

      static acc_code generalized_co_buchi(unsigned n)
      {
507
508
509
510
        acc_cond::mark_t m = (1U << n) - 1;
        if (n == 8 * sizeof(mark_t::value_t))
          m = mark_t(-1U);
        return fin(m);
511
512
513
514
515
      }

      // n is a number of pairs.
      static acc_code rabin(unsigned n)
      {
516
517
518
519
520
521
522
        acc_cond::acc_code res = f();
        while (n > 0)
          {
            res |= inf({2*n - 1}) & fin({2*n - 2});
            --n;
          }
        return res;
523
524
525
526
527
      }

       // n is a number of pairs.
      static acc_code streett(unsigned n)
      {
528
529
530
531
532
533
534
        acc_cond::acc_code res = t();
        while (n > 0)
          {
            res &= inf({2*n - 1}) | fin({2*n - 2});
            --n;
          }
        return res;
535
536
      }

537
538
      template<class Iterator>
      static acc_code generalized_rabin(Iterator begin, Iterator end)
539
      {
540
541
542
543
544
545
546
547
548
549
550
551
552
        acc_cond::acc_code res = f();
        unsigned n = 0;
        for (Iterator i = begin; i != end; ++i)
          {
            acc_cond::acc_code pair = fin({n++});
            acc_cond::mark_t m = 0U;
            for (unsigned ni = *i; ni > 0; --ni)
              m.set(n++);
            pair &= inf(m);
            std::swap(pair, res);
            res |= std::move(pair);
          }
        return res;
553
554
      }

555
556
      static acc_code parity(bool max, bool odd, unsigned sets);

557
558
559
560
561
      // Number of acceptance sets to use, and probability to reuse
      // each set another time after it has been used in the
      // acceptance formula.
      static acc_code random(unsigned n, double reuse = 0.0);

562
      acc_code& operator&=(acc_code&& r)
563
      {
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
        if (is_t() || r.is_f())
          {
            *this = std::move(r);
            return *this;
          }
        if (is_f() || r.is_t())
          return *this;
        unsigned s = size() - 1;
        unsigned rs = r.size() - 1;
        // We want to group all Inf(x) operators:
        //   Inf(a) & Inf(b) = Inf(a & b)
        if (((*this)[s].op == acc_op::Inf && r[rs].op == acc_op::Inf)
            || ((*this)[s].op == acc_op::InfNeg && r[rs].op == acc_op::InfNeg))
          {
            (*this)[s - 1].mark |= r[rs - 1].mark;
            return *this;
          }

        // In the more complex scenarios, left and right may both
        // be conjunctions, and Inf(x) might be a member of each
        // side.  Find it if it exists.
        // left_inf points to the left Inf mark if any.
        // right_inf points to the right Inf mark if any.
        acc_word* left_inf = nullptr;
        if ((*this)[s].op == acc_op::And)
          {
            auto start = &(*this)[s] - (*this)[s].size;
            auto pos = &(*this)[s] - 1;
            pop_back();
            while (pos > start)
              {
                if (pos->op == acc_op::Inf)
                  {
                    left_inf = pos - 1;
                    break;
                  }
                pos -= pos->size + 1;
              }
          }
        else if ((*this)[s].op == acc_op::Inf)
          {
            left_inf = &(*this)[s - 1];
          }

        acc_word* right_inf = nullptr;
        auto right_end = &r.back();
        if (right_end->op == acc_op::And)
          {
            auto start = &r[0];
            auto pos = --right_end;
            while (pos > start)
            {
              if (pos->op == acc_op::Inf)
                {
                  right_inf = pos - 1;
                  break;
                }
              pos -= pos->size + 1;
            }
          }
        else if (right_end->op == acc_op::Inf)
          {
            right_inf = right_end - 1;
          }

        if (left_inf && right_inf)
          {
            left_inf->mark |= right_inf->mark;
            insert(this->end(), &r[0], right_inf);
            insert(this->end(), right_inf + 2, right_end + 1);
          }
        else if (right_inf)
          {
            // Always insert Inf() at the very first entry.
            insert(this->begin(), right_inf, right_inf + 2);
            insert(this->end(), &r[0], right_inf);
            insert(this->end(), right_inf + 2, right_end + 1);
          }
        else
          {
            insert(this->end(), &r[0], right_end + 1);
          }

        acc_word w;
        w.op = acc_op::And;
        w.size = size();
        push_back(w);
        return *this;
652
653
      }

654
      acc_code& operator&=(const acc_code& r)
655
      {
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
        if (is_t() || r.is_f())
          {
            *this = r;
            return *this;
          }
        if (is_f() || r.is_t())
          return *this;
        unsigned s = size() - 1;
        unsigned rs = r.size() - 1;
        // Inf(a) & Inf(b) = Inf(a & b)
        if (((*this)[s].op == acc_op::Inf && r[rs].op == acc_op::Inf)
            || ((*this)[s].op == acc_op::InfNeg && r[rs].op == acc_op::InfNeg))
          {
            (*this)[s - 1].mark |= r[rs - 1].mark;
            return *this;
          }

        // In the more complex scenarios, left and right may both
        // be conjunctions, and Inf(x) might be a member of each
        // side.  Find it if it exists.
        // left_inf points to the left Inf mark if any.
        // right_inf points to the right Inf mark if any.
        acc_word* left_inf = nullptr;
        if ((*this)[s].op == acc_op::And)
          {
            auto start = &(*this)[s] - (*this)[s].size;
            auto pos = &(*this)[s] - 1;
            pop_back();
            while (pos > start)
              {
                if (pos->op == acc_op::Inf)
                  {
                    left_inf = pos - 1;
                    break;
                  }
                pos -= pos->size + 1;
              }
          }
        else if ((*this)[s].op == acc_op::Inf)
          {
            left_inf = &(*this)[s - 1];
          }

        const acc_word* right_inf = nullptr;
        auto right_end = &r.back();
        if (right_end->op == acc_op::And)
          {
            auto start = &r[0];
            auto pos = --right_end;
            while (pos > start)
            {
              if (pos->op == acc_op::Inf)
                {
                  right_inf = pos - 1;
                  break;
                }
              pos -= pos->size + 1;
            }
          }
        else if (right_end->op == acc_op::Inf)
          {
            right_inf = right_end - 1;
          }

        if (left_inf && right_inf)
          {
            left_inf->mark |= right_inf->mark;
            insert(this->end(), &r[0], right_inf);
            insert(this->end(), right_inf + 2, right_end + 1);
          }
        else if (right_inf)
          {
            // Always insert Inf() at the very first entry.
            insert(this->begin(), right_inf, right_inf + 2);
            insert(this->end(), &r[0], right_inf);
            insert(this->end(), right_inf + 2, right_end + 1);
          }
        else
          {
            insert(this->end(), &r[0], right_end + 1);
          }

        acc_word w;
        w.op = acc_op::And;
        w.size = size();
        push_back(w);
        return *this;
743
744
745
746
      }

      acc_code operator&(acc_code&& r)
      {
747
748
749
        acc_code res = *this;
        res &= r;
        return res;
750
751
      }

752
753
      acc_code operator&(const acc_code& r)
      {
754
755
756
        acc_code res = *this;
        res &= r;
        return res;
757
758
759
      }

      acc_code& operator|=(acc_code&& r)
760
      {
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
        if (is_t() || r.is_f())
          return *this;
        if (is_f() || r.is_t())
          {
            *this = std::move(r);
            return *this;
          }
        unsigned s = size() - 1;
        unsigned rs = r.size() - 1;
        // Fin(a) | Fin(b) = Fin(a | b)
        if (((*this)[s].op == acc_op::Fin && r[rs].op == acc_op::Fin)
            || ((*this)[s].op == acc_op::FinNeg && r[rs].op == acc_op::FinNeg))
          {
            (*this)[s - 1].mark |= r[rs - 1].mark;
            return *this;
          }
        if ((*this)[s].op == acc_op::Or)
          pop_back();
        if (r.back().op == acc_op::Or)
          r.pop_back();
        insert(this->end(), r.begin(), r.end());
        acc_word w;
        w.op = acc_op::Or;
        w.size = size();
        push_back(w);
        return *this;
787
788
789
790
      }

      acc_code& operator|=(const acc_code& r)
      {
791
        return *this |= acc_code(r);
792
793
794
795
      }

      acc_code operator|(acc_code&& r)
      {
796
797
798
        acc_code res = *this;
        res |= r;
        return res;
799
800
      }

801
802
      acc_code operator|(const acc_code& r)
      {
803
804
805
        acc_code res = *this;
        res |= r;
        return res;
806
807
808
      }

      acc_code& operator<<=(unsigned sets)
809
      {
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
        if (empty())
          return *this;
        unsigned pos = size();
        do
          {
            switch ((*this)[pos - 1].op)
              {
              case acc_cond::acc_op::And:
              case acc_cond::acc_op::Or:
                --pos;
                break;
              case acc_cond::acc_op::Inf:
              case acc_cond::acc_op::InfNeg:
              case acc_cond::acc_op::Fin:
              case acc_cond::acc_op::FinNeg:
                pos -= 2;
                (*this)[pos].mark.id <<= sets;
                break;
              }
          }
        while (pos > 0);
        return *this;
832
833
834
835
      }

      acc_code operator<<(unsigned sets) const
      {
836
837
838
        acc_code res = *this;
        res <<= sets;
        return res;
839
      }
840

841
      bool is_dnf() const;
842
      bool is_cnf() const;
843

844
      acc_code to_dnf() const;
845
      acc_code to_cnf() const;
846

847
848
      acc_code complement() const;

849
850
851
852
853
854
      // Return a list of acceptance marks needed to close a cycle
      // that already visit INF infinitely often, so that the cycle is
      // accepting (ACCEPTING=true) or rejecting (ACCEPTING=false).
      // Positive values describe positive set.
      // A negative value x means the set -x-1 must be absent.
      std::vector<std::vector<int>>
855
        missing(mark_t inf, bool accepting) const;
856
857
858
859
860

      bool accepting(mark_t inf) const;

      bool inf_satisfiable(mark_t inf) const;

861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
      // Remove all the acceptance sets in rem.
      //
      // If MISSING is set, the acceptance sets are assumed to be
      // missing from the automaton, and the acceptance is updated to
      // reflect this.  For instance (Inf(1)&Inf(2))|Fin(3) will
      // become Fin(3) if we remove 2 because it is missing from this
      // automaton, because there is no way to fulfill Inf(1)&Inf(2)
      // in this case.  So essentially MISSING causes Inf(rem) to
      // become f, and Fin(rem) to become t.
      //
      // If MISSING is unset, Inf(rem) become t while Fin(rem) become
      // f.  Removing 2 from (Inf(1)&Inf(2))|Fin(3) would then give
      // Inf(1)|Fin(3).
      acc_code strip(acc_cond::mark_t rem, bool missing) const;

      // Return the set of sets appearing in the condition.
      acc_cond::mark_t used_sets() const;

879
880
881
882
883
884
885
      // Return the sets used as Inf or Fin in the acceptance condition
      std::pair<acc_cond::mark_t, acc_cond::mark_t> used_inf_fin_sets() const;

      // Print the acceptance as HTML.  The set_printer function can
      // be used to implement customized output for set numbers.
      std::ostream&
      to_html(std::ostream& os,
886
887
              std::function<void(std::ostream&, int)>
              set_printer = nullptr) const;
888
889
890
891
892

      // Print the acceptance as text.  The set_printer function can
      // be used to implement customized output for set numbers.
      std::ostream&
      to_text(std::ostream& os,
893
894
              std::function<void(std::ostream&, int)>
              set_printer = nullptr) const;
895

896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927

      /// \brief Construct an acc_code from a string.
      ///
      /// The string can follow the following grammar:
      ///
      /// <pre>
      ///   acc ::= "t"
      ///         | "f"
      ///         | "Inf" "(" num ")"
      ///         | "Fin" "(" num ")"
      ///         | "(" acc ")"
      ///         | acc "&" acc
      ///         | acc "|" acc
      /// </pre>
      ///
      /// Where num is an integer and "&" has priority over "|".  Note that
      /// "Fin(!x)" and "Inf(!x)" are not supported by this parser.
      ///
      /// Or the string can be the name of an acceptance condition, as
      /// speficied in the HOA format.  (E.g. "Rabin 2", "parity max odd 3",
      /// "generalized-Rabin 4 2 1", etc.).
      ///
      /// A spot::parse_error is thrown on syntax error.
      acc_code(const char* input);

      /// \brief Build an empty acceptance condition.
      ///
      /// This is the same as t().
      acc_code()
      {
      }

928
      // Calls to_text
929
930
      SPOT_API
      friend std::ostream& operator<<(std::ostream& os, const acc_code& code);
931
932
    };

933
    acc_cond(unsigned n_sets = 0, const acc_code& code = {})
934
      : num_(0U), all_(0U), code_(code)
935
936
    {
      add_sets(n_sets);
937
938
939
940
941
942
943
944
      uses_fin_acceptance_ = check_fin_acceptance();
    }

    acc_cond(const acc_code& code)
      : num_(0U), all_(0U), code_(code)
    {
      add_sets(code.used_sets().max_set());
      uses_fin_acceptance_ = check_fin_acceptance();
945
946
947
    }

    acc_cond(const acc_cond& o)
948
949
      : num_(o.num_), all_(o.all_), code_(o.code_),
        uses_fin_acceptance_(o.uses_fin_acceptance_)
950
951
952
953
954
955
956
    {
    }

    ~acc_cond()
    {
    }

957
958
959
960
961
962
    void set_acceptance(const acc_code& code)
    {
      code_ = code;
      uses_fin_acceptance_ = check_fin_acceptance();
    }

963
    const acc_code& get_acceptance() const
964
965
966
967
    {
      return code_;
    }

968
969
970
971
972
    acc_code& get_acceptance()
    {
      return code_;
    }

973
974
975
976
977
    bool uses_fin_acceptance() const
    {
      return uses_fin_acceptance_;
    }

978
    bool is_t() const
979
    {
980
      return code_.is_t();
981
982
    }

983
    bool is_all() const
984
    {
985
986
987
988
989
990
991
992
993
994
995
      return num_ == 0 && is_t();
    }

    bool is_f() const
    {
      return code_.is_f();
    }

    bool is_none() const
    {
      return num_ == 0 && is_f();
996
997
998
999
1000
1001
    }

    bool is_buchi() const
    {
      unsigned s = code_.size();
      return num_ == 1 &&
1002
        s == 2 && code_[1].op == acc_op::Inf && code_[0].mark == all_sets();
1003
1004
1005
1006
1007
1008
1009
    }

    bool is_co_buchi() const
    {
      return num_ == 1 && is_generalized_co_buchi();
    }

1010
1011
1012
1013
1014
1015
1016
1017
1018
    void set_generalized_buchi()
    {
      set_acceptance(inf(all_sets()));
    }

    bool is_generalized_buchi() const
    {
      unsigned s = code_.size();
      return (s == 0 && num_ == 0) ||
1019
        (s == 2 && code_[1].op == acc_op::Inf && code_[0].mark == all_sets());
1020
1021
    }

1022
1023
1024
1025
    bool is_generalized_co_buchi() const
    {
      unsigned s = code_.size();
      return (s == 2 &&
1026
              code_[1].op == acc_op::Fin && code_[0].mark == all_sets());
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
    }

    // Returns a number of pairs (>=0) if Rabin, or -1 else.
    int is_rabin() const;
    // Returns a number of pairs (>=0) if Streett, or -1 else.
    int is_streett() const;

    // Return the number of Inf in each pair.
    bool is_generalized_rabin(std::vector<unsigned>& pairs) const;

1037
1038
1039
1040
1041
1042
    // If EQUIV is false, this return true iff the acceptance
    // condition is a parity condition written in the canonical way
    // given in the HOA specifications.  If EQUIV is true, then we
    // check whether the condition is logically equivalent to some
    // parity acceptance condition.
    bool is_parity(bool& max, bool& odd, bool equiv = false) const;
1043
1044
1045
1046
1047
1048
    bool is_parity() const
    {
      bool max;
      bool min;
      return is_parity(max, min);
    }
1049

1050
1051
1052
1053
1054
    // Return (true, m) if there exist some acceptance mark m that
    // does not satisfy the acceptance condition.  Return (false, 0U)
    // otherwise.
    std::pair<bool, acc_cond::mark_t> unsat_mark() const;

1055
1056
1057
  protected:
    bool check_fin_acceptance() const;

1058
1059
1060
  public:
    acc_code inf(mark_t mark) const
    {
1061
      return acc_code::inf(mark);
1062
1063
1064
1065
    }

    acc_code inf(std::initializer_list<unsigned> vals) const
    {
1066
      return inf(mark_t(vals.begin(), vals.end()));
1067
1068
1069
1070
    }

    acc_code inf_neg(mark_t mark) const
    {
1071
      return acc_code::inf_neg(mark);
1072
1073
1074
1075
    }

    acc_code inf_neg(std::initializer_list<unsigned> vals) const
    {
1076
      return inf_neg(mark_t(vals.begin(), vals.end()));
1077
1078
1079
1080
    }

    acc_code fin(mark_t mark) const
    {
1081
      return acc_code::fin(mark);
1082
1083
1084
1085
    }

    acc_code fin(std::initializer_list<unsigned> vals) const
    {
1086
      return fin(mark_t(vals.begin(), vals.end()));
1087
1088
1089
1090
    }

    acc_code fin_neg(mark_t mark) const
    {
1091
      return acc_code::fin_neg(mark);
1092
1093
1094
1095
    }

    acc_code fin_neg(std::initializer_list<unsigned> vals) const
    {
1096
      return fin_neg(mark_t(vals.begin(), vals.end()));
1097
1098
    }

1099
1100
1101
    unsigned add_sets(unsigned num)
    {
      if (num == 0)
1102
        return -1U;
1103
1104
1105
      unsigned j = num_;
      num_ += num;
      if (num_ > 8 * sizeof(mark_t::id))
1106
        throw std::runtime_error("Too many acceptance sets used.");
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
      all_ = all_sets_();
      return j;
    }

    unsigned add_set()
    {
      return add_sets(1);
    }

    mark_t mark(unsigned u) const
    {
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1118
1119
      assert(u < num_sets());
      return 1U << u;
1120
1121
1122
1123
    }

    mark_t comp(mark_t l) const
    {
1124
      return all_ ^ l.id;
1125
1126
1127
1128
    }

    mark_t all_sets() const
    {
1129
      return all_;
1130
1131
    }

1132
1133
1134
1135
    bool accepting(mark_t inf) const
    {
      return code_.accepting(inf);
    }
1136

1137
1138
1139
1140
    bool inf_satisfiable(mark_t inf) const
    {
      return code_.inf_satisfiable(inf);
    }
1141

1142
    mark_t accepting_sets(mark_t inf) const;
1143
1144
1145

    std::ostream& format(std::ostream& os, mark_t m) const
    {
1146
      auto a = m;
1147
      if (a == 0U)
1148
        return os;
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
      return os << m;
    }

    std::string format(mark_t m) const
    {
      std::ostringstream os;
      format(os, m);
      return os.str();
    }

    unsigned num_sets() const
    {
      return num_;
    }

    template<class iterator>
    mark_t useless(iterator begin, iterator end) const
    {
1167
      mark_t::value_t u = 0U;        // The set of useless marks.
1168
      for (unsigned x = 0; x < num_; ++x)
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
        {
          // Skip marks that are already known to be useless.
          if (u & (1 << x))
            continue;
          unsigned all = all_ ^ (u | (1 << x));
          for (iterator y = begin; y != end; ++y)
            {
              auto v = y->id;
              if (v & (1 << x))
                {
                  all &= v;
                  if (!all)
                    break;
                }
            }
          u |= all;
        }
1186
      return u;
1187
1188
1189
1190
1191
1192
    }

  protected:
    mark_t::value_t all_sets_() const
    {
      if (num_ == 0)
1193
        return 0;
1194
1195
1196
1197
1198
      return -1U >> (8 * sizeof(mark_t::value_t) - num_);
    }

    unsigned num_;
    mark_t::value_t all_;
1199
1200
    acc_code code_;
    bool uses_fin_acceptance_ = false;
1201

1202
1203
  };

1204
1205
  SPOT_API
  std::ostream& operator<<(std::ostream& os, const acc_cond& acc);
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
}

namespace std
{
  template<>
  struct hash<spot::acc_cond::mark_t>
  {
    size_t operator()(spot::acc_cond::mark_t m) const
    {
      std::hash<decltype(m.id)> h;
      return h(m.id);
    }
  };
}