GCC Code Coverage Report
Directory: . Exec Total Coverage
File: src/theory/quantifiers/term_util.cpp Lines: 259 309 83.8 %
Date: 2021-08-17 Branches: 560 1020 54.9 %

Line Exec Source
1
/******************************************************************************
2
 * Top contributors (to current version):
3
 *   Andrew Reynolds, Mathias Preiner, Aina Niemetz
4
 *
5
 * This file is part of the cvc5 project.
6
 *
7
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
8
 * in the top-level source directory and their institutional affiliations.
9
 * All rights reserved.  See the file COPYING in the top-level source
10
 * directory for licensing information.
11
 * ****************************************************************************
12
 *
13
 * Implementation of term utilities class.
14
 */
15
16
#include "theory/quantifiers/term_util.h"
17
18
#include "expr/node_algorithm.h"
19
#include "theory/arith/arith_msum.h"
20
#include "theory/bv/theory_bv_utils.h"
21
#include "theory/quantifiers/term_database.h"
22
#include "theory/quantifiers/term_enumeration.h"
23
#include "theory/rewriter.h"
24
#include "theory/strings/word.h"
25
#include "util/bitvector.h"
26
#include "util/rational.h"
27
28
using namespace cvc5::kind;
29
30
namespace cvc5 {
31
namespace theory {
32
namespace quantifiers {
33
34
5253
size_t TermUtil::getVariableNum(Node q, Node v)
35
{
36
5253
  Node::iterator it = std::find(q[0].begin(), q[0].end(), v);
37
5253
  Assert(it != q[0].end());
38
5253
  return it - q[0].begin();
39
}
40
41
16166
Node TermUtil::getRemoveQuantifiers2( Node n, std::map< Node, Node >& visited ) {
42
16166
  std::map< Node, Node >::iterator it = visited.find( n );
43
16166
  if( it!=visited.end() ){
44
7221
    return it->second;
45
  }else{
46
17890
    Node ret = n;
47
8945
    if( n.getKind()==FORALL ){
48
373
      ret = getRemoveQuantifiers2( n[1], visited );
49
8572
    }else if( n.getNumChildren()>0 ){
50
12954
      std::vector< Node > children;
51
6477
      bool childrenChanged = false;
52
21887
      for( unsigned i=0; i<n.getNumChildren(); i++ ){
53
30820
        Node ni = getRemoveQuantifiers2( n[i], visited );
54
15410
        childrenChanged = childrenChanged || ni!=n[i];
55
15410
        children.push_back( ni );
56
      }
57
6477
      if( childrenChanged ){
58
3
        if( n.getMetaKind() == kind::metakind::PARAMETERIZED ){
59
          children.insert( children.begin(), n.getOperator() );
60
        }
61
3
        ret = NodeManager::currentNM()->mkNode( n.getKind(), children );
62
      }
63
    }
64
8945
    visited[n] = ret;
65
8945
    return ret;
66
  }
67
}
68
69
11693061
Node TermUtil::getInstConstAttr( Node n ) {
70
11693061
  if (!n.hasAttribute(InstConstantAttribute()) ){
71
927396
    Node q;
72
463698
    if (n.hasOperator())
73
    {
74
339037
      q = getInstConstAttr(n.getOperator());
75
    }
76
463698
    if (q.isNull())
77
    {
78
963753
      for (const Node& nc : n)
79
      {
80
602079
        q = getInstConstAttr(nc);
81
602079
        if (!q.isNull())
82
        {
83
101957
          break;
84
        }
85
      }
86
    }
87
    InstConstantAttribute ica;
88
463698
    n.setAttribute(ica, q);
89
  }
90
11693061
  return n.getAttribute(InstConstantAttribute());
91
}
92
93
7533011
bool TermUtil::hasInstConstAttr( Node n ) {
94
7533011
  return !getInstConstAttr(n).isNull();
95
}
96
97
158737
Node TermUtil::getBoundVarAttr( Node n ) {
98
158737
  if (!n.hasAttribute(BoundVarAttribute()) ){
99
165466
    Node bv;
100
82733
    if( n.getKind()==BOUND_VARIABLE ){
101
7732
      bv = n;
102
    }else{
103
100362
      for( unsigned i=0; i<n.getNumChildren(); i++ ){
104
84183
        bv = getBoundVarAttr(n[i]);
105
84183
        if( !bv.isNull() ){
106
58822
          break;
107
        }
108
      }
109
    }
110
    BoundVarAttribute bva;
111
82733
    n.setAttribute(bva, bv);
112
  }
113
158737
  return n.getAttribute(BoundVarAttribute());
114
}
115
116
74554
bool TermUtil::hasBoundVarAttr( Node n ) {
117
74554
  return !getBoundVarAttr(n).isNull();
118
}
119
120
//remove quantifiers
121
383
Node TermUtil::getRemoveQuantifiers( Node n ) {
122
766
  std::map< Node, Node > visited;
123
766
  return getRemoveQuantifiers2( n, visited );
124
}
125
126
//quantified simplify
127
954
Node TermUtil::getQuantSimplify( Node n ) {
128
1908
  std::unordered_set<Node> fvs;
129
954
  expr::getFreeVariables(n, fvs);
130
954
  if (fvs.empty())
131
  {
132
571
    return Rewriter::rewrite( n );
133
  }
134
766
  std::vector<Node> bvs;
135
383
  bvs.insert(bvs.end(), fvs.begin(), fvs.end());
136
383
  NodeManager* nm = NodeManager::currentNM();
137
766
  Node q = nm->mkNode(FORALL, nm->mkNode(BOUND_VAR_LIST, bvs), n);
138
383
  q = Rewriter::rewrite(q);
139
383
  return getRemoveQuantifiers(q);
140
}
141
142
155673
void TermUtil::computeInstConstContains(Node n, std::vector<Node>& ics)
143
{
144
155673
  computeVarContainsInternal(n, INST_CONSTANT, ics);
145
155673
}
146
147
void TermUtil::computeVarContains(Node n, std::vector<Node>& vars)
148
{
149
  computeVarContainsInternal(n, BOUND_VARIABLE, vars);
150
}
151
152
1611
void TermUtil::computeQuantContains(Node n, std::vector<Node>& quants)
153
{
154
1611
  computeVarContainsInternal(n, FORALL, quants);
155
1611
}
156
157
157284
void TermUtil::computeVarContainsInternal(Node n,
158
                                          Kind k,
159
                                          std::vector<Node>& vars)
160
{
161
314568
  std::unordered_set<TNode> visited;
162
157284
  std::unordered_set<TNode>::iterator it;
163
314568
  std::vector<TNode> visit;
164
314568
  TNode cur;
165
157284
  visit.push_back(n);
166
1239166
  do
167
  {
168
1396450
    cur = visit.back();
169
1396450
    visit.pop_back();
170
1396450
    it = visited.find(cur);
171
172
1396450
    if (it == visited.end())
173
    {
174
1248431
      visited.insert(cur);
175
1248431
      if (cur.getKind() == k)
176
      {
177
367939
        if (std::find(vars.begin(), vars.end(), cur) == vars.end())
178
        {
179
367939
          vars.push_back(cur);
180
        }
181
      }
182
      else
183
      {
184
880492
        if (cur.hasOperator())
185
        {
186
415226
          visit.push_back(cur.getOperator());
187
        }
188
1704432
        for (const Node& cn : cur)
189
        {
190
823940
          visit.push_back(cn);
191
        }
192
      }
193
    }
194
1396450
  } while (!visit.empty());
195
157284
}
196
197
108275
void TermUtil::computeInstConstContainsForQuant(Node q,
198
                                                Node n,
199
                                                std::vector<Node>& vars)
200
{
201
216550
  std::vector<Node> ics;
202
108275
  computeInstConstContains(n, ics);
203
366451
  for (const Node& v : ics)
204
  {
205
258176
    if (v.getAttribute(InstConstantAttribute()) == q)
206
    {
207
258176
      if (std::find(vars.begin(), vars.end(), v) == vars.end())
208
      {
209
258174
        vars.push_back(v);
210
      }
211
    }
212
  }
213
108275
}
214
215
int TermUtil::getTermDepth( Node n ) {
216
  if (!n.hasAttribute(TermDepthAttribute()) ){
217
    int maxDepth = -1;
218
    for( unsigned i=0; i<n.getNumChildren(); i++ ){
219
      int depth = getTermDepth( n[i] );
220
      if( depth>maxDepth ){
221
        maxDepth = depth;
222
      }
223
    }
224
    TermDepthAttribute tda;
225
    n.setAttribute(tda,1+maxDepth);
226
  }
227
  return n.getAttribute(TermDepthAttribute());
228
}
229
230
495797
bool TermUtil::containsUninterpretedConstant( Node n ) {
231
495797
  if (!n.hasAttribute(ContainsUConstAttribute()) ){
232
23454
    bool ret = false;
233
23454
    if( n.getKind()==UNINTERPRETED_CONSTANT ){
234
818
      ret = true;
235
    }else{
236
43120
      for( unsigned i=0; i<n.getNumChildren(); i++ ){
237
20484
        if( containsUninterpretedConstant( n[i] ) ){
238
          ret = true;
239
          break;
240
        }
241
      }
242
    }
243
    ContainsUConstAttribute cuca;
244
23454
    n.setAttribute(cuca, ret ? 1 : 0);
245
  }
246
495797
  return n.getAttribute(ContainsUConstAttribute())!=0;
247
}
248
249
4646
Node TermUtil::simpleNegate(Node n)
250
{
251
4646
  Assert(n.getType().isBoolean());
252
4646
  NodeManager* nm = NodeManager::currentNM();
253
4646
  if( n.getKind()==OR || n.getKind()==AND ){
254
2670
    std::vector< Node > children;
255
5263
    for (const Node& cn : n)
256
    {
257
3928
      children.push_back(simpleNegate(cn));
258
    }
259
1335
    return nm->mkNode(n.getKind() == OR ? AND : OR, children);
260
  }
261
3311
  else if (n.isConst())
262
  {
263
79
    return nm->mkConst(!n.getConst<bool>());
264
  }
265
3232
  return n.negate();
266
}
267
268
945
Node TermUtil::mkNegate(Kind notk, Node n)
269
{
270
945
  if (n.getKind() == notk)
271
  {
272
34
    return n[0];
273
  }
274
911
  return NodeManager::currentNM()->mkNode(notk, n);
275
}
276
277
2725
bool TermUtil::isNegate(Kind k)
278
{
279
2725
  return k == NOT || k == BITVECTOR_NOT || k == BITVECTOR_NEG || k == UMINUS;
280
}
281
282
105947
bool TermUtil::isAssoc(Kind k, bool reqNAry)
283
{
284
105947
  if (reqNAry)
285
  {
286
105444
    if (k == UNION || k == INTERSECTION)
287
    {
288
27
      return false;
289
    }
290
  }
291
91533
  return k == PLUS || k == MULT || k == NONLINEAR_MULT || k == AND || k == OR
292
74030
         || k == XOR || k == BITVECTOR_ADD || k == BITVECTOR_MULT
293
69142
         || k == BITVECTOR_AND || k == BITVECTOR_OR || k == BITVECTOR_XOR
294
62953
         || k == BITVECTOR_XNOR || k == BITVECTOR_CONCAT || k == STRING_CONCAT
295
61565
         || k == UNION || k == INTERSECTION || k == JOIN || k == PRODUCT
296
167481
         || k == SEP_STAR;
297
}
298
299
391712
bool TermUtil::isComm(Kind k, bool reqNAry)
300
{
301
391712
  if (reqNAry)
302
  {
303
    if (k == UNION || k == INTERSECTION)
304
    {
305
      return false;
306
    }
307
  }
308
331385
  return k == EQUAL || k == PLUS || k == MULT || k == NONLINEAR_MULT || k == AND
309
274638
         || k == OR || k == XOR || k == BITVECTOR_ADD || k == BITVECTOR_MULT
310
245316
         || k == BITVECTOR_AND || k == BITVECTOR_OR || k == BITVECTOR_XOR
311
238683
         || k == BITVECTOR_XNOR || k == UNION || k == INTERSECTION
312
630309
         || k == SEP_STAR;
313
}
314
315
105597
bool TermUtil::isNonAdditive( Kind k ) {
316
105597
  return k==AND || k==OR || k==BITVECTOR_AND || k==BITVECTOR_OR;
317
}
318
319
334338
bool TermUtil::isBoolConnective( Kind k ) {
320
334338
  return k==OR || k==AND || k==EQUAL || k==ITE || k==FORALL || k==NOT || k==SEP_STAR;
321
}
322
323
281103
bool TermUtil::isBoolConnectiveTerm( TNode n ) {
324
481504
  return isBoolConnective( n.getKind() ) &&
325
1172407
         ( n.getKind()!=EQUAL || n[0].getType().isBoolean() ) &&
326
682498
         ( n.getKind()!=ITE || n.getType().isBoolean() );
327
}
328
329
19002
Node TermUtil::mkTypeValue(TypeNode tn, int32_t val)
330
{
331
19002
  Node n;
332
19002
  if (tn.isInteger() || tn.isReal())
333
  {
334
6184
    Rational c(val);
335
3092
    n = NodeManager::currentNM()->mkConst(c);
336
  }
337
15910
  else if (tn.isBitVector())
338
  {
339
    // cast to unsigned
340
1173
    uint32_t uv = static_cast<uint32_t>(val);
341
2346
    BitVector bval(tn.getConst<BitVectorSize>(), uv);
342
1173
    n = NodeManager::currentNM()->mkConst<BitVector>(bval);
343
  }
344
14737
  else if (tn.isBoolean())
345
  {
346
14497
    if (val == 0)
347
    {
348
14098
      n = NodeManager::currentNM()->mkConst(false);
349
    }
350
  }
351
240
  else if (tn.isStringLike())
352
  {
353
150
    if (val == 0)
354
    {
355
87
      n = strings::Word::mkEmptyWord(tn);
356
    }
357
  }
358
19002
  return n;
359
}
360
361
14920
Node TermUtil::mkTypeMaxValue(TypeNode tn)
362
{
363
14920
  Node n;
364
14920
  if (tn.isBitVector())
365
  {
366
373
    n = bv::utils::mkOnes(tn.getConst<BitVectorSize>());
367
  }
368
14547
  else if (tn.isBoolean())
369
  {
370
13878
    n = NodeManager::currentNM()->mkConst(true);
371
  }
372
14920
  return n;
373
}
374
375
4
Node TermUtil::mkTypeValueOffset(TypeNode tn,
376
                                 Node val,
377
                                 int32_t offset,
378
                                 int32_t& status)
379
{
380
4
  Node val_o;
381
8
  Node offset_val = mkTypeValue(tn, offset);
382
4
  status = -1;
383
4
  if (!offset_val.isNull())
384
  {
385
4
    if (tn.isInteger() || tn.isReal())
386
    {
387
4
      val_o = Rewriter::rewrite(
388
8
          NodeManager::currentNM()->mkNode(PLUS, val, offset_val));
389
4
      status = 0;
390
    }
391
    else if (tn.isBitVector())
392
    {
393
      val_o = Rewriter::rewrite(
394
          NodeManager::currentNM()->mkNode(BITVECTOR_ADD, val, offset_val));
395
    }
396
  }
397
8
  return val_o;
398
}
399
400
2
Node TermUtil::mkTypeConst(TypeNode tn, bool pol)
401
{
402
2
  return pol ? mkTypeMaxValue(tn) : mkTypeValue(tn, 0);
403
}
404
405
bool TermUtil::isAntisymmetric(Kind k, Kind& dk)
406
{
407
  if (k == GT)
408
  {
409
    dk = LT;
410
    return true;
411
  }
412
  else if (k == GEQ)
413
  {
414
    dk = LEQ;
415
    return true;
416
  }
417
  else if (k == BITVECTOR_UGT)
418
  {
419
    dk = BITVECTOR_ULT;
420
    return true;
421
  }
422
  else if (k == BITVECTOR_UGE)
423
  {
424
    dk = BITVECTOR_ULE;
425
    return true;
426
  }
427
  else if (k == BITVECTOR_SGT)
428
  {
429
    dk = BITVECTOR_SLT;
430
    return true;
431
  }
432
  else if (k == BITVECTOR_SGE)
433
  {
434
    dk = BITVECTOR_SLE;
435
    return true;
436
  }
437
  return false;
438
}
439
440
1195
bool TermUtil::isIdempotentArg(Node n, Kind ik, int arg)
441
{
442
  // these should all be binary operators
443
  // Assert( ik!=DIVISION && ik!=INTS_DIVISION && ik!=INTS_MODULUS &&
444
  // ik!=BITVECTOR_UDIV );
445
2390
  TypeNode tn = n.getType();
446
1195
  if (n == mkTypeValue(tn, 0))
447
  {
448
555
    if (ik == PLUS || ik == OR || ik == XOR || ik == BITVECTOR_ADD
449
428
        || ik == BITVECTOR_OR || ik == BITVECTOR_XOR || ik == STRING_CONCAT)
450
    {
451
144
      return true;
452
    }
453
411
    else if (ik == MINUS || ik == BITVECTOR_SHL || ik == BITVECTOR_LSHR
454
361
             || ik == BITVECTOR_ASHR || ik == BITVECTOR_SUB
455
361
             || ik == BITVECTOR_UREM)
456
    {
457
57
      return arg == 1;
458
    }
459
  }
460
640
  else if (n == mkTypeValue(tn, 1))
461
  {
462
379
    if (ik == MULT || ik == BITVECTOR_MULT)
463
    {
464
5
      return true;
465
    }
466
374
    else if (ik == DIVISION || ik == DIVISION_TOTAL || ik == INTS_DIVISION
467
370
             || ik == INTS_DIVISION_TOTAL
468
370
             || ik == INTS_MODULUS
469
370
             || ik == INTS_MODULUS_TOTAL
470
370
             || ik == BITVECTOR_UDIV
471
363
             || ik == BITVECTOR_SDIV)
472
    {
473
20
      return arg == 1;
474
    }
475
  }
476
261
  else if (n == mkTypeMaxValue(tn))
477
  {
478
170
    if (ik == EQUAL || ik == BITVECTOR_AND || ik == BITVECTOR_XNOR)
479
    {
480
      return true;
481
    }
482
  }
483
969
  return false;
484
}
485
486
1006
Node TermUtil::isSingularArg(Node n, Kind ik, unsigned arg)
487
{
488
2012
  TypeNode tn = n.getType();
489
1006
  if (n == mkTypeValue(tn, 0))
490
  {
491
382
    if (ik == AND || ik == MULT || ik == BITVECTOR_AND || ik == BITVECTOR_MULT)
492
    {
493
47
      return n;
494
    }
495
335
    else if (ik == BITVECTOR_SHL || ik == BITVECTOR_LSHR || ik == BITVECTOR_ASHR
496
335
             || ik == BITVECTOR_UREM)
497
    {
498
3
      if (arg == 0)
499
      {
500
3
        return n;
501
      }
502
    }
503
332
    else if (ik == BITVECTOR_UDIV || ik == BITVECTOR_UDIV
504
325
             || ik == BITVECTOR_SDIV)
505
    {
506
14
      if (arg == 0)
507
      {
508
6
        return n;
509
      }
510
8
      else if (arg == 1)
511
      {
512
8
        return mkTypeMaxValue(tn);
513
      }
514
    }
515
318
    else if (ik == DIVISION || ik == DIVISION_TOTAL || ik == INTS_DIVISION
516
316
             || ik == INTS_DIVISION_TOTAL
517
316
             || ik == INTS_MODULUS
518
313
             || ik == INTS_MODULUS_TOTAL)
519
    {
520
7
      if (arg == 0)
521
      {
522
3
        return n;
523
      }
524
    }
525
313
    else if (ik == STRING_SUBSTR)
526
    {
527
      if (arg == 0)
528
      {
529
        return n;
530
      }
531
      else if (arg == 2)
532
      {
533
        return mkTypeValue(NodeManager::currentNM()->stringType(), 0);
534
      }
535
    }
536
313
    else if (ik == STRING_INDEXOF)
537
    {
538
      if (arg == 0 || arg == 1)
539
      {
540
        return mkTypeValue(NodeManager::currentNM()->integerType(), -1);
541
      }
542
    }
543
  }
544
624
  else if (n == mkTypeValue(tn, 1))
545
  {
546
363
    if (ik == BITVECTOR_UREM)
547
    {
548
7
      return mkTypeValue(tn, 0);
549
    }
550
  }
551
261
  else if (n == mkTypeMaxValue(tn))
552
  {
553
170
    if (ik == OR || ik == BITVECTOR_OR)
554
    {
555
57
      return n;
556
    }
557
  }
558
  else
559
  {
560
91
    if (n.getType().isReal() && n.getConst<Rational>().sgn() < 0)
561
    {
562
      // negative arguments
563
2
      if (ik == STRING_SUBSTR || ik == STRING_CHARAT)
564
      {
565
        return mkTypeValue(NodeManager::currentNM()->stringType(), 0);
566
      }
567
2
      else if (ik == STRING_INDEXOF)
568
      {
569
        Assert(arg == 2);
570
        return mkTypeValue(NodeManager::currentNM()->integerType(), -1);
571
      }
572
    }
573
  }
574
875
  return Node::null();
575
}
576
577
676
bool TermUtil::hasOffsetArg(Kind ik, int arg, int& offset, Kind& ok)
578
{
579
676
  if (ik == LT)
580
  {
581
4
    Assert(arg == 0 || arg == 1);
582
4
    offset = arg == 0 ? 1 : -1;
583
4
    ok = LEQ;
584
4
    return true;
585
  }
586
672
  else if (ik == BITVECTOR_ULT)
587
  {
588
12
    Assert(arg == 0 || arg == 1);
589
12
    offset = arg == 0 ? 1 : -1;
590
12
    ok = BITVECTOR_ULE;
591
12
    return true;
592
  }
593
660
  else if (ik == BITVECTOR_SLT)
594
  {
595
12
    Assert(arg == 0 || arg == 1);
596
12
    offset = arg == 0 ? 1 : -1;
597
12
    ok = BITVECTOR_SLE;
598
12
    return true;
599
  }
600
648
  return false;
601
}
602
603
}  // namespace quantifiers
604
}  // namespace theory
605
29337
}  // namespace cvc5