GCC Code Coverage Report
Directory: . Exec Total Coverage
File: src/theory/bv/theory_bv_utils.cpp Lines: 218 238 91.6 %
Date: 2021-05-22 Branches: 341 812 42.0 %

Line Exec Source
1
/******************************************************************************
2
 * Top contributors (to current version):
3
 *   Aina Niemetz, Andrew Reynolds, Liana Hadarean
4
 *
5
 * This file is part of the cvc5 project.
6
 *
7
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
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 * in the top-level source directory and their institutional affiliations.
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 * All rights reserved.  See the file COPYING in the top-level source
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 * directory for licensing information.
11
 * ****************************************************************************
12
 *
13
 * Util functions for theory BV.
14
 */
15
16
#include "theory/bv/theory_bv_utils.h"
17
18
#include <vector>
19
20
#include "expr/skolem_manager.h"
21
#include "options/theory_options.h"
22
#include "theory/theory.h"
23
24
namespace cvc5 {
25
namespace theory {
26
namespace bv {
27
namespace utils {
28
29
/* ------------------------------------------------------------------------- */
30
31
4484212
unsigned getSize(TNode node)
32
{
33
4484212
  return node.getType().getBitVectorSize();
34
}
35
36
45
const bool getBit(TNode node, unsigned i)
37
{
38
45
  Assert(i < getSize(node) && node.getKind() == kind::CONST_BITVECTOR);
39
45
  return node.getConst<BitVector>().extract(i, i).getValue() == 1u;
40
}
41
42
/* ------------------------------------------------------------------------- */
43
44
462526
unsigned getExtractHigh(TNode node)
45
{
46
462526
  return node.getOperator().getConst<BitVectorExtract>().d_high;
47
}
48
49
444626
unsigned getExtractLow(TNode node)
50
{
51
444626
  return node.getOperator().getConst<BitVectorExtract>().d_low;
52
}
53
54
70
unsigned getSignExtendAmount(TNode node)
55
{
56
70
  return node.getOperator().getConst<BitVectorSignExtend>().d_signExtendAmount;
57
}
58
59
/* ------------------------------------------------------------------------- */
60
61
3432
bool isOnes(TNode node)
62
{
63
3432
  if (!node.isConst()) return false;
64
77
  return node == mkOnes(getSize(node));
65
}
66
67
13414
bool isZero(TNode node)
68
{
69
13414
  if (!node.isConst()) return false;
70
10029
  return node == mkZero(getSize(node));
71
}
72
73
4161
bool isOne(TNode node)
74
{
75
4161
  if (!node.isConst()) return false;
76
806
  return node == mkOne(getSize(node));
77
}
78
79
666704
unsigned isPow2Const(TNode node, bool& isNeg)
80
{
81
666704
  if (node.getKind() != kind::CONST_BITVECTOR)
82
  {
83
457440
    return false;
84
  }
85
86
418528
  BitVector bv = node.getConst<BitVector>();
87
209264
  unsigned p = bv.isPow2();
88
209264
  if (p != 0)
89
  {
90
22077
    isNeg = false;
91
22077
    return p;
92
  }
93
374374
  BitVector nbv = -bv;
94
187187
  p = nbv.isPow2();
95
187187
  if (p != 0)
96
  {
97
5104
    isNeg = true;
98
5104
    return p;
99
  }
100
182083
  return false;
101
}
102
103
901887
bool isBvConstTerm(TNode node)
104
{
105
901887
  if (node.getNumChildren() == 0)
106
  {
107
    return node.isConst();
108
  }
109
110
1602385
  for (const TNode& n : node)
111
  {
112
1251723
    if (!n.isConst()) { return false; }
113
  }
114
350662
  return true;
115
}
116
117
16
bool isBVPredicate(TNode node)
118
{
119
16
  Kind k = node.getKind();
120
16
  if (k == kind::NOT)
121
  {
122
    node = node[0];
123
    k = node.getKind();
124
  }
125
  return k == kind::EQUAL
126
4
         || k == kind::BITVECTOR_ULT
127
4
         || k == kind::BITVECTOR_SLT
128
4
         || k == kind::BITVECTOR_UGT
129
4
         || k == kind::BITVECTOR_UGE
130
4
         || k == kind::BITVECTOR_SGT
131
4
         || k == kind::BITVECTOR_SGE
132
4
         || k == kind::BITVECTOR_ULE
133
4
         || k == kind::BITVECTOR_SLE
134
4
         || k == kind::BITVECTOR_REDOR
135
20
         || k == kind::BITVECTOR_REDAND;
136
}
137
138
51144
static bool isCoreEqTerm(bool iseq, TNode term, TNodeBoolMap& cache)
139
{
140
102288
  TNode t = term.getKind() == kind::NOT ? term[0] : term;
141
142
102288
  std::vector<TNode> stack;
143
102288
  std::unordered_map<TNode, bool> visited;
144
51144
  stack.push_back(t);
145
146
541046
  while (!stack.empty())
147
  {
148
374425
    TNode n = stack.back();
149
244951
    stack.pop_back();
150
151
244951
    if (cache.find(n) != cache.end()) continue;
152
153
248063
    if (n.getNumChildren() == 0)
154
    {
155
57748
      cache[n] = true;
156
57748
      visited[n] = true;
157
57748
      continue;
158
    }
159
160
265134
    if (theory::Theory::theoryOf(options::TheoryOfMode::THEORY_OF_TERM_BASED, n)
161
132567
        == theory::THEORY_BV)
162
    {
163
75391
      Kind k = n.getKind();
164
75391
      Assert(k != kind::CONST_BITVECTOR);
165
78484
      if (k != kind::EQUAL
166
3093
          && (iseq || k != kind::BITVECTOR_CONCAT)
167
3093
          && (iseq || k != kind::BITVECTOR_EXTRACT)
168
78484
          && n.getMetaKind() != kind::metakind::VARIABLE)
169
      {
170
3093
        cache[n] = false;
171
3093
        continue;
172
      }
173
    }
174
175
129474
    if (!visited[n])
176
    {
177
64737
      visited[n] = true;
178
64737
      stack.push_back(n);
179
64737
      stack.insert(stack.end(), n.begin(), n.end());
180
    }
181
    else
182
    {
183
64737
      bool iseqt = true;
184
190248
      for (const Node& c : n)
185
      {
186
127267
        Assert(cache.find(c) != cache.end());
187
127267
        if (!cache[c])
188
        {
189
1756
          iseqt = false;
190
1756
          break;
191
        }
192
      }
193
64737
      cache[n] = iseqt;
194
    }
195
  }
196
51144
  Assert(cache.find(t) != cache.end());
197
102288
  return cache[t];
198
}
199
200
bool isCoreTerm(TNode term, TNodeBoolMap& cache)
201
{
202
  return isCoreEqTerm(false, term, cache);
203
}
204
205
51144
bool isEqualityTerm(TNode term, TNodeBoolMap& cache)
206
{
207
51144
  return isCoreEqTerm(true, term, cache);
208
}
209
210
2129119
bool isBitblastAtom(Node lit)
211
{
212
4258238
  TNode atom = lit.getKind() == kind::NOT ? lit[0] : lit;
213
4258238
  return atom.getKind() != kind::EQUAL || atom[0].getType().isBitVector();
214
}
215
216
/* ------------------------------------------------------------------------- */
217
218
37444
Node mkTrue()
219
{
220
37444
  return NodeManager::currentNM()->mkConst<bool>(true);
221
}
222
223
75839
Node mkFalse()
224
{
225
75839
  return NodeManager::currentNM()->mkConst<bool>(false);
226
}
227
228
211782
Node mkZero(unsigned size)
229
{
230
211782
  Assert(size > 0);
231
211782
  return mkConst(size, 0u);
232
}
233
234
14244
Node mkOne(unsigned size)
235
{
236
14244
  Assert(size > 0);
237
14244
  return mkConst(size, 1u);
238
}
239
240
21804
Node mkOnes(unsigned size)
241
{
242
21804
  Assert(size > 0);
243
21804
  return mkConst(BitVector::mkOnes(size));
244
}
245
246
54
Node mkMinSigned(unsigned size)
247
{
248
54
  Assert(size > 0);
249
54
  return mkConst(BitVector::mkMinSigned(size));
250
}
251
252
64
Node mkMaxSigned(unsigned size)
253
{
254
64
  Assert(size > 0);
255
64
  return mkConst(BitVector::mkMaxSigned(size));
256
}
257
258
/* ------------------------------------------------------------------------- */
259
260
598266
Node mkConst(unsigned size, unsigned int value)
261
{
262
1196532
  BitVector val(size, value);
263
1196532
  return NodeManager::currentNM()->mkConst<BitVector>(val);
264
}
265
266
59554
Node mkConst(unsigned size, Integer& value)
267
{
268
59554
  return NodeManager::currentNM()->mkConst<BitVector>(BitVector(size, value));
269
}
270
271
932730
Node mkConst(const BitVector& value)
272
{
273
932730
  return NodeManager::currentNM()->mkConst<BitVector>(value);
274
}
275
276
/* ------------------------------------------------------------------------- */
277
278
94
Node mkVar(unsigned size)
279
{
280
94
  NodeManager* nm = NodeManager::currentNM();
281
94
  SkolemManager* sm = nm->getSkolemManager();
282
  return sm->mkDummySkolem("BVSKOLEM$$",
283
188
                           nm->mkBitVectorType(size),
284
282
                           "is a variable created by the theory of bitvectors");
285
}
286
287
/* ------------------------------------------------------------------------- */
288
289
Node mkSortedNode(Kind kind, TNode child1, TNode child2)
290
{
291
  Assert(kind == kind::BITVECTOR_AND || kind == kind::BITVECTOR_OR
292
         || kind == kind::BITVECTOR_XOR);
293
294
  if (child1 < child2)
295
  {
296
    return NodeManager::currentNM()->mkNode(kind, child1, child2);
297
  }
298
  else
299
  {
300
    return NodeManager::currentNM()->mkNode(kind, child2, child1);
301
  }
302
}
303
304
257372
Node mkSortedNode(Kind kind, std::vector<Node>& children)
305
{
306
257372
  Assert(kind == kind::BITVECTOR_AND || kind == kind::BITVECTOR_OR
307
         || kind == kind::BITVECTOR_XOR);
308
257372
  Assert(children.size() > 0);
309
257372
  if (children.size() == 1)
310
  {
311
54188
    return children[0];
312
  }
313
203184
  std::sort(children.begin(), children.end());
314
203184
  return NodeManager::currentNM()->mkNode(kind, children);
315
}
316
317
/* ------------------------------------------------------------------------- */
318
319
Node mkNot(Node child)
320
{
321
  return NodeManager::currentNM()->mkNode(kind::NOT, child);
322
}
323
324
Node mkAnd(TNode node1, TNode node2)
325
{
326
  return NodeManager::currentNM()->mkNode(kind::AND, node1, node2);
327
}
328
329
Node mkOr(TNode node1, TNode node2)
330
{
331
  return NodeManager::currentNM()->mkNode(kind::OR, node1, node2);
332
}
333
334
Node mkXor(TNode node1, TNode node2)
335
{
336
  return NodeManager::currentNM()->mkNode(kind::XOR, node1, node2);
337
}
338
339
/* ------------------------------------------------------------------------- */
340
341
394
Node mkSignExtend(TNode node, unsigned amount)
342
{
343
394
  NodeManager* nm = NodeManager::currentNM();
344
  Node signExtendOp =
345
788
      nm->mkConst<BitVectorSignExtend>(BitVectorSignExtend(amount));
346
788
  return nm->mkNode(signExtendOp, node);
347
}
348
349
/* ------------------------------------------------------------------------- */
350
351
51625
Node mkExtract(TNode node, unsigned high, unsigned low)
352
{
353
51625
  NodeManager *nm = NodeManager::currentNM();
354
103250
  Node extractOp = nm->mkConst<BitVectorExtract>(BitVectorExtract(high, low));
355
103250
  return nm->mkNode(extractOp, node);
356
}
357
358
210484
Node mkBitOf(TNode node, unsigned index)
359
{
360
210484
  NodeManager *nm = NodeManager::currentNM();
361
420968
  Node bitOfOp = nm->mkConst<BitVectorBitOf>(BitVectorBitOf(index));
362
420968
  return nm->mkNode(bitOfOp, node);
363
}
364
365
/* ------------------------------------------------------------------------- */
366
367
25859
Node mkConcat(TNode t1, TNode t2)
368
{
369
25859
  return NodeManager::currentNM()->mkNode(kind::BITVECTOR_CONCAT, t1, t2);
370
}
371
372
568148
Node mkConcat(std::vector<Node>& children)
373
{
374
568148
  if (children.size() > 1)
375
506887
    return NodeManager::currentNM()->mkNode(kind::BITVECTOR_CONCAT, children);
376
  else
377
61261
    return children[0];
378
}
379
380
670
Node mkConcat(TNode node, unsigned repeat)
381
{
382
670
  Assert(repeat);
383
670
  if (repeat == 1)
384
  {
385
101
    return node;
386
  }
387
1138
  NodeBuilder result(kind::BITVECTOR_CONCAT);
388
7025
  for (unsigned i = 0; i < repeat; ++i)
389
  {
390
6456
    result << node;
391
  }
392
1138
  Node resultNode = result;
393
569
  return resultNode;
394
}
395
396
/* ------------------------------------------------------------------------- */
397
398
Node mkInc(TNode t)
399
{
400
  return NodeManager::currentNM()->mkNode(
401
      kind::BITVECTOR_ADD, t, mkOne(getSize(t)));
402
}
403
404
2
Node mkDec(TNode t)
405
{
406
  return NodeManager::currentNM()->mkNode(
407
2
      kind::BITVECTOR_SUB, t, mkOne(getSize(t)));
408
}
409
410
/* ------------------------------------------------------------------------- */
411
412
30
Node mkUmulo(TNode t1, TNode t2)
413
{
414
30
  unsigned w = getSize(t1);
415
30
  if (w == 1) return mkFalse();
416
417
28
  NodeManager* nm = NodeManager::currentNM();
418
56
  Node uppc;
419
56
  std::vector<Node> tmp;
420
421
28
  uppc = mkExtract(t1, w - 1, w - 1);
422
238
  for (size_t i = 1; i < w; ++i)
423
  {
424
210
    tmp.push_back(nm->mkNode(kind::BITVECTOR_AND, mkExtract(t2, i, i), uppc));
425
630
    uppc = nm->mkNode(
426
420
        kind::BITVECTOR_OR, mkExtract(t1, w - 1 - i, w - 1 - i), uppc);
427
  }
428
56
  Node zext_t1 = mkConcat(mkZero(1), t1);
429
56
  Node zext_t2 = mkConcat(mkZero(1), t2);
430
56
  Node mul = nm->mkNode(kind::BITVECTOR_MULT, zext_t1, zext_t2);
431
28
  tmp.push_back(mkExtract(mul, w, w));
432
28
  return nm->mkNode(kind::EQUAL, nm->mkNode(kind::BITVECTOR_OR, tmp), mkOne(1));
433
}
434
435
/* ------------------------------------------------------------------------- */
436
437
840
Node flattenAnd(std::vector<TNode>& queue)
438
{
439
1680
  TNodeSet nodes;
440
6284
  while (!queue.empty())
441
  {
442
5444
    TNode current = queue.back();
443
2722
    queue.pop_back();
444
2722
    if (current.getKind() == kind::AND)
445
    {
446
16
      for (const TNode& n : current)
447
      {
448
11
        if (nodes.count(n) == 0) { queue.push_back(n); }
449
      }
450
    }
451
    else
452
    {
453
2717
      nodes.insert(current);
454
    }
455
  }
456
1680
  std::vector<TNode> children(nodes.begin(), nodes.end());
457
1680
  return mkAnd(children);
458
}
459
460
/* ------------------------------------------------------------------------- */
461
462
290
Node eliminateBv2Nat(TNode node)
463
{
464
290
  const unsigned size = utils::getSize(node[0]);
465
290
  NodeManager* const nm = NodeManager::currentNM();
466
580
  const Node z = nm->mkConst(Rational(0));
467
580
  const Node bvone = utils::mkOne(1);
468
469
580
  Integer i = 1;
470
580
  std::vector<Node> children;
471
1575
  for (unsigned bit = 0; bit < size; ++bit, i *= 2)
472
  {
473
    Node cond =
474
        nm->mkNode(kind::EQUAL,
475
2570
                   nm->mkNode(nm->mkConst(BitVectorExtract(bit, bit)), node[0]),
476
5140
                   bvone);
477
1285
    children.push_back(
478
2570
        nm->mkNode(kind::ITE, cond, nm->mkConst(Rational(i)), z));
479
  }
480
  // avoid plus with one child
481
580
  return children.size() == 1 ? children[0] : nm->mkNode(kind::PLUS, children);
482
}
483
484
356
Node eliminateInt2Bv(TNode node)
485
{
486
356
  const uint32_t size = node.getOperator().getConst<IntToBitVector>().d_size;
487
356
  NodeManager* const nm = NodeManager::currentNM();
488
712
  const Node bvzero = utils::mkZero(1);
489
712
  const Node bvone = utils::mkOne(1);
490
491
712
  std::vector<Node> v;
492
712
  Integer i = 2;
493
3828
  while (v.size() < size)
494
  {
495
    Node cond = nm->mkNode(
496
        kind::GEQ,
497
3472
        nm->mkNode(kind::INTS_MODULUS_TOTAL, node[0], nm->mkConst(Rational(i))),
498
6944
        nm->mkConst(Rational(i, 2)));
499
1736
    v.push_back(nm->mkNode(kind::ITE, cond, bvone, bvzero));
500
1736
    i *= 2;
501
  }
502
356
  if (v.size() == 1)
503
  {
504
5
    return v[0];
505
  }
506
702
  NodeBuilder result(kind::BITVECTOR_CONCAT);
507
351
  result.append(v.rbegin(), v.rend());
508
351
  return Node(result);
509
}
510
511
}  // namespace utils
512
}  // namespace bv
513
}  // namespace theory
514
28191
}  // namespace cvc5