Unify CVC4_CHECK/CVC4_DCHECK/AlwaysAssert/Assert. (#3366)
[cvc5.git] / src / theory / theory_engine.cpp
1 /********************* */
2 /*! \file theory_engine.cpp
3 ** \verbatim
4 ** Top contributors (to current version):
5 ** Dejan Jovanovic, Morgan Deters, Andrew Reynolds
6 ** This file is part of the CVC4 project.
7 ** Copyright (c) 2009-2019 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.\endverbatim
11 **
12 ** \brief The theory engine
13 **
14 ** The theory engine.
15 **/
16
17 #include "theory/theory_engine.h"
18
19 #include <list>
20 #include <vector>
21
22 #include "base/map_util.h"
23 #include "decision/decision_engine.h"
24 #include "expr/attribute.h"
25 #include "expr/node.h"
26 #include "expr/node_algorithm.h"
27 #include "expr/node_builder.h"
28 #include "options/bv_options.h"
29 #include "options/options.h"
30 #include "options/proof_options.h"
31 #include "options/quantifiers_options.h"
32 #include "preprocessing/assertion_pipeline.h"
33 #include "proof/cnf_proof.h"
34 #include "proof/lemma_proof.h"
35 #include "proof/proof_manager.h"
36 #include "proof/theory_proof.h"
37 #include "smt/logic_exception.h"
38 #include "smt/term_formula_removal.h"
39 #include "smt_util/lemma_output_channel.h"
40 #include "smt_util/node_visitor.h"
41 #include "theory/arith/arith_ite_utils.h"
42 #include "theory/bv/theory_bv_utils.h"
43 #include "theory/care_graph.h"
44 #include "theory/quantifiers/first_order_model.h"
45 #include "theory/quantifiers/fmf/model_engine.h"
46 #include "theory/quantifiers/theory_quantifiers.h"
47 #include "theory/quantifiers_engine.h"
48 #include "theory/rewriter.h"
49 #include "theory/theory.h"
50 #include "theory/theory_model.h"
51 #include "theory/theory_traits.h"
52 #include "theory/uf/equality_engine.h"
53 #include "util/resource_manager.h"
54
55 using namespace std;
56
57 using namespace CVC4::preprocessing;
58 using namespace CVC4::theory;
59
60 namespace CVC4 {
61
62 /* -------------------------------------------------------------------------- */
63
64 namespace theory {
65
66 /**
67 * IMPORTANT: The order of the theories is important. For example, strings
68 * depends on arith, quantifiers needs to come as the very last.
69 * Do not change this order.
70 */
71
72 #define CVC4_FOR_EACH_THEORY \
73 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_BUILTIN) \
74 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_BOOL) \
75 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_UF) \
76 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_ARITH) \
77 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_BV) \
78 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_FP) \
79 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_ARRAYS) \
80 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_DATATYPES) \
81 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_SEP) \
82 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_SETS) \
83 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_STRINGS) \
84 CVC4_FOR_EACH_THEORY_STATEMENT(CVC4::theory::THEORY_QUANTIFIERS)
85
86 } // namespace theory
87
88 /* -------------------------------------------------------------------------- */
89
90 inline void flattenAnd(Node n, std::vector<TNode>& out){
91 Assert(n.getKind() == kind::AND);
92 for(Node::iterator i=n.begin(), i_end=n.end(); i != i_end; ++i){
93 Node curr = *i;
94 if(curr.getKind() == kind::AND){
95 flattenAnd(curr, out);
96 }else{
97 out.push_back(curr);
98 }
99 }
100 }
101
102 inline Node flattenAnd(Node n){
103 std::vector<TNode> out;
104 flattenAnd(n, out);
105 return NodeManager::currentNM()->mkNode(kind::AND, out);
106 }
107
108 /**
109 * Compute the string for a given theory id. In this module, we use
110 * THEORY_SAT_SOLVER as an id, which is not a normal id but maps to
111 * THEORY_LAST. Thus, we need our own string conversion here.
112 *
113 * @param id The theory id
114 * @return The string corresponding to the theory id
115 */
116 std::string getTheoryString(theory::TheoryId id)
117 {
118 if (id == theory::THEORY_SAT_SOLVER)
119 {
120 return "THEORY_SAT_SOLVER";
121 }
122 else
123 {
124 std::stringstream ss;
125 ss << id;
126 return ss.str();
127 }
128 }
129
130 theory::LemmaStatus TheoryEngine::EngineOutputChannel::lemma(TNode lemma,
131 ProofRule rule,
132 bool removable,
133 bool preprocess,
134 bool sendAtoms) {
135 Debug("theory::lemma") << "EngineOutputChannel<" << d_theory << ">::lemma("
136 << lemma << ")"
137 << ", preprocess = " << preprocess << std::endl;
138 ++d_statistics.lemmas;
139 d_engine->d_outputChannelUsed = true;
140
141 PROOF({ registerLemmaRecipe(lemma, lemma, preprocess, d_theory); });
142
143 theory::LemmaStatus result =
144 d_engine->lemma(lemma, rule, false, removable, preprocess,
145 sendAtoms ? d_theory : theory::THEORY_LAST);
146 return result;
147 }
148
149 void TheoryEngine::EngineOutputChannel::registerLemmaRecipe(Node lemma, Node originalLemma, bool preprocess, theory::TheoryId theoryId) {
150 // During CNF conversion, conjunctions will be broken down into
151 // multiple lemmas. In order for the recipes to match, we have to do
152 // the same here.
153 NodeManager* nm = NodeManager::currentNM();
154
155 if (preprocess)
156 lemma = d_engine->preprocess(lemma);
157
158 bool negated = (lemma.getKind() == kind::NOT);
159 Node nnLemma = negated ? lemma[0] : lemma;
160
161 switch (nnLemma.getKind()) {
162
163 case kind::AND:
164 if (!negated) {
165 for (unsigned i = 0; i < nnLemma.getNumChildren(); ++i)
166 registerLemmaRecipe(nnLemma[i], originalLemma, false, theoryId);
167 } else {
168 NodeBuilder<> builder(kind::OR);
169 for (unsigned i = 0; i < nnLemma.getNumChildren(); ++i)
170 builder << nnLemma[i].negate();
171
172 Node disjunction = (builder.getNumChildren() == 1) ? builder[0] : builder;
173 registerLemmaRecipe(disjunction, originalLemma, false, theoryId);
174 }
175 break;
176
177 case kind::EQUAL:
178 if( nnLemma[0].getType().isBoolean() ){
179 if (!negated) {
180 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0], nnLemma[1].negate()), originalLemma, false, theoryId);
181 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0].negate(), nnLemma[1]), originalLemma, false, theoryId);
182 } else {
183 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0], nnLemma[1]), originalLemma, false, theoryId);
184 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0].negate(), nnLemma[1].negate()), originalLemma, false, theoryId);
185 }
186 }
187 break;
188
189 case kind::ITE:
190 if (!negated) {
191 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0].negate(), nnLemma[1]), originalLemma, false, theoryId);
192 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0], nnLemma[2]), originalLemma, false, theoryId);
193 } else {
194 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0].negate(), nnLemma[1].negate()), originalLemma, false, theoryId);
195 registerLemmaRecipe(nm->mkNode(kind::OR, nnLemma[0], nnLemma[2].negate()), originalLemma, false, theoryId);
196 }
197 break;
198
199 default:
200 break;
201 }
202
203 // Theory lemmas have one step that proves the empty clause
204 LemmaProofRecipe proofRecipe;
205 Node emptyNode;
206 LemmaProofRecipe::ProofStep proofStep(theoryId, emptyNode);
207
208 // Remember the original lemma, so we can report this later when asked to
209 proofRecipe.setOriginalLemma(originalLemma);
210
211 // Record the assertions and rewrites
212 Node rewritten;
213 if (lemma.getKind() == kind::OR) {
214 for (unsigned i = 0; i < lemma.getNumChildren(); ++i) {
215 rewritten = theory::Rewriter::rewrite(lemma[i]);
216 if (rewritten != lemma[i]) {
217 proofRecipe.addRewriteRule(lemma[i].negate(), rewritten.negate());
218 }
219 proofStep.addAssertion(lemma[i]);
220 proofRecipe.addBaseAssertion(rewritten);
221 }
222 } else {
223 rewritten = theory::Rewriter::rewrite(lemma);
224 if (rewritten != lemma) {
225 proofRecipe.addRewriteRule(lemma.negate(), rewritten.negate());
226 }
227 proofStep.addAssertion(lemma);
228 proofRecipe.addBaseAssertion(rewritten);
229 }
230 proofRecipe.addStep(proofStep);
231 ProofManager::getCnfProof()->setProofRecipe(&proofRecipe);
232 }
233
234 theory::LemmaStatus TheoryEngine::EngineOutputChannel::splitLemma(
235 TNode lemma, bool removable) {
236 Debug("theory::lemma") << "EngineOutputChannel<" << d_theory << ">::lemma("
237 << lemma << ")" << std::endl;
238 ++d_statistics.lemmas;
239 d_engine->d_outputChannelUsed = true;
240
241 Debug("pf::explain") << "TheoryEngine::EngineOutputChannel::splitLemma( "
242 << lemma << " )" << std::endl;
243 theory::LemmaStatus result =
244 d_engine->lemma(lemma, RULE_SPLIT, false, removable, false, d_theory);
245 return result;
246 }
247
248 bool TheoryEngine::EngineOutputChannel::propagate(TNode literal) {
249 Debug("theory::propagate") << "EngineOutputChannel<" << d_theory
250 << ">::propagate(" << literal << ")" << std::endl;
251 ++d_statistics.propagations;
252 d_engine->d_outputChannelUsed = true;
253 return d_engine->propagate(literal, d_theory);
254 }
255
256 void TheoryEngine::EngineOutputChannel::conflict(TNode conflictNode,
257 std::unique_ptr<Proof> proof)
258 {
259 Trace("theory::conflict")
260 << "EngineOutputChannel<" << d_theory << ">::conflict(" << conflictNode
261 << ")" << std::endl;
262 Assert(!proof); // Theory shouldn't be producing proofs yet
263 ++d_statistics.conflicts;
264 d_engine->d_outputChannelUsed = true;
265 d_engine->conflict(conflictNode, d_theory);
266 }
267
268 void TheoryEngine::finishInit() {
269
270 //initialize the quantifiers engine, master equality engine, model, model builder
271 if( d_logicInfo.isQuantified() ) {
272 // initialize the quantifiers engine
273 d_quantEngine = new QuantifiersEngine(d_context, d_userContext, this);
274 Assert(d_masterEqualityEngine == 0);
275 d_masterEqualityEngine = new eq::EqualityEngine(d_masterEENotify,getSatContext(), "theory::master", false);
276
277 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId != theory::THEORY_LAST; ++ theoryId) {
278 if (d_theoryTable[theoryId]) {
279 d_theoryTable[theoryId]->setQuantifiersEngine(d_quantEngine);
280 d_theoryTable[theoryId]->setMasterEqualityEngine(d_masterEqualityEngine);
281 }
282 }
283
284 d_curr_model_builder = d_quantEngine->getModelBuilder();
285 d_curr_model = d_quantEngine->getModel();
286 } else {
287 d_curr_model = new theory::TheoryModel(
288 d_userContext, "DefaultModel", options::assignFunctionValues());
289 d_aloc_curr_model = true;
290 }
291 //make the default builder, e.g. in the case that the quantifiers engine does not have a model builder
292 if( d_curr_model_builder==NULL ){
293 d_curr_model_builder = new theory::TheoryEngineModelBuilder(this);
294 d_aloc_curr_model_builder = true;
295 }
296
297 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId != theory::THEORY_LAST; ++ theoryId) {
298 if (d_theoryTable[theoryId]) {
299 // set the decision manager for the theory
300 d_theoryTable[theoryId]->setDecisionManager(d_decManager.get());
301 // finish initializing the theory
302 d_theoryTable[theoryId]->finishInit();
303 }
304 }
305 }
306
307 void TheoryEngine::eqNotifyNewClass(TNode t){
308 if (d_logicInfo.isQuantified()) {
309 d_quantEngine->eqNotifyNewClass( t );
310 }
311 }
312
313 TheoryEngine::TheoryEngine(context::Context* context,
314 context::UserContext* userContext,
315 RemoveTermFormulas& iteRemover,
316 const LogicInfo& logicInfo,
317 LemmaChannels* channels)
318 : d_propEngine(nullptr),
319 d_decisionEngine(nullptr),
320 d_context(context),
321 d_userContext(userContext),
322 d_logicInfo(logicInfo),
323 d_sharedTerms(this, context),
324 d_masterEqualityEngine(nullptr),
325 d_masterEENotify(*this),
326 d_quantEngine(nullptr),
327 d_decManager(new DecisionManager(userContext)),
328 d_curr_model(nullptr),
329 d_aloc_curr_model(false),
330 d_curr_model_builder(nullptr),
331 d_aloc_curr_model_builder(false),
332 d_eager_model_building(false),
333 d_ppCache(),
334 d_possiblePropagations(context),
335 d_hasPropagated(context),
336 d_inConflict(context, false),
337 d_inSatMode(false),
338 d_hasShutDown(false),
339 d_incomplete(context, false),
340 d_propagationMap(context),
341 d_propagationMapTimestamp(context, 0),
342 d_propagatedLiterals(context),
343 d_propagatedLiteralsIndex(context, 0),
344 d_atomRequests(context),
345 d_tform_remover(iteRemover),
346 d_combineTheoriesTime("TheoryEngine::combineTheoriesTime"),
347 d_true(),
348 d_false(),
349 d_interrupted(false),
350 d_resourceManager(NodeManager::currentResourceManager()),
351 d_channels(channels),
352 d_inPreregister(false),
353 d_factsAsserted(context, false),
354 d_preRegistrationVisitor(this, context),
355 d_sharedTermsVisitor(d_sharedTerms),
356 d_theoryAlternatives(),
357 d_attr_handle(),
358 d_arithSubstitutionsAdded("theory::arith::zzz::arith::substitutions", 0)
359 {
360 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId != theory::THEORY_LAST;
361 ++ theoryId)
362 {
363 d_theoryTable[theoryId] = NULL;
364 d_theoryOut[theoryId] = NULL;
365 }
366
367 smtStatisticsRegistry()->registerStat(&d_combineTheoriesTime);
368 d_true = NodeManager::currentNM()->mkConst<bool>(true);
369 d_false = NodeManager::currentNM()->mkConst<bool>(false);
370
371 #ifdef CVC4_PROOF
372 ProofManager::currentPM()->initTheoryProofEngine();
373 #endif
374
375 smtStatisticsRegistry()->registerStat(&d_arithSubstitutionsAdded);
376 }
377
378 TheoryEngine::~TheoryEngine() {
379 Assert(d_hasShutDown);
380
381 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId != theory::THEORY_LAST; ++ theoryId) {
382 if(d_theoryTable[theoryId] != NULL) {
383 delete d_theoryTable[theoryId];
384 delete d_theoryOut[theoryId];
385 }
386 }
387
388 if( d_aloc_curr_model_builder ){
389 delete d_curr_model_builder;
390 }
391 if( d_aloc_curr_model ){
392 delete d_curr_model;
393 }
394
395 delete d_quantEngine;
396
397 delete d_masterEqualityEngine;
398
399 smtStatisticsRegistry()->unregisterStat(&d_combineTheoriesTime);
400 smtStatisticsRegistry()->unregisterStat(&d_arithSubstitutionsAdded);
401 }
402
403 void TheoryEngine::interrupt() { d_interrupted = true; }
404 void TheoryEngine::preRegister(TNode preprocessed) {
405
406 Debug("theory") << "TheoryEngine::preRegister( " << preprocessed << ")" << std::endl;
407 if(Dump.isOn("missed-t-propagations")) {
408 d_possiblePropagations.push_back(preprocessed);
409 }
410 d_preregisterQueue.push(preprocessed);
411
412 if (!d_inPreregister) {
413 // We're in pre-register
414 d_inPreregister = true;
415
416 // Process the pre-registration queue
417 while (!d_preregisterQueue.empty()) {
418 // Get the next atom to pre-register
419 preprocessed = d_preregisterQueue.front();
420 d_preregisterQueue.pop();
421
422 if (d_logicInfo.isSharingEnabled() && preprocessed.getKind() == kind::EQUAL) {
423 // When sharing is enabled, we propagate from the shared terms manager also
424 d_sharedTerms.addEqualityToPropagate(preprocessed);
425 }
426
427 // the atom should not have free variables
428 Debug("theory") << "TheoryEngine::preRegister: " << preprocessed
429 << std::endl;
430 Assert(!expr::hasFreeVar(preprocessed));
431 // Pre-register the terms in the atom
432 Theory::Set theories = NodeVisitor<PreRegisterVisitor>::run(d_preRegistrationVisitor, preprocessed);
433 theories = Theory::setRemove(THEORY_BOOL, theories);
434 // Remove the top theory, if any more that means multiple theories were involved
435 bool multipleTheories = Theory::setRemove(Theory::theoryOf(preprocessed), theories);
436 TheoryId i;
437 // These checks don't work with finite model finding, because it
438 // uses Rational constants to represent cardinality constraints,
439 // even though arithmetic isn't actually involved.
440 if(!options::finiteModelFind()) {
441 while((i = Theory::setPop(theories)) != THEORY_LAST) {
442 if(!d_logicInfo.isTheoryEnabled(i)) {
443 LogicInfo newLogicInfo = d_logicInfo.getUnlockedCopy();
444 newLogicInfo.enableTheory(i);
445 newLogicInfo.lock();
446 stringstream ss;
447 ss << "The logic was specified as " << d_logicInfo.getLogicString()
448 << ", which doesn't include " << i
449 << ", but found a term in that theory." << endl
450 << "You might want to extend your logic to "
451 << newLogicInfo.getLogicString() << endl;
452 throw LogicException(ss.str());
453 }
454 }
455 }
456 if (multipleTheories) {
457 // Collect the shared terms if there are multiple theories
458 NodeVisitor<SharedTermsVisitor>::run(d_sharedTermsVisitor, preprocessed);
459 }
460 }
461
462 // Leaving pre-register
463 d_inPreregister = false;
464 }
465 }
466
467 void TheoryEngine::printAssertions(const char* tag) {
468 if (Trace.isOn(tag)) {
469
470 for (TheoryId theoryId = THEORY_FIRST; theoryId < THEORY_LAST; ++theoryId) {
471 Theory* theory = d_theoryTable[theoryId];
472 if (theory && d_logicInfo.isTheoryEnabled(theoryId)) {
473 Trace(tag) << "--------------------------------------------" << endl;
474 Trace(tag) << "Assertions of " << theory->getId() << ": " << endl;
475 context::CDList<Assertion>::const_iterator it = theory->facts_begin(), it_end = theory->facts_end();
476 for (unsigned i = 0; it != it_end; ++ it, ++i) {
477 if ((*it).isPreregistered) {
478 Trace(tag) << "[" << i << "]: ";
479 } else {
480 Trace(tag) << "(" << i << "): ";
481 }
482 Trace(tag) << (*it).assertion << endl;
483 }
484
485 if (d_logicInfo.isSharingEnabled()) {
486 Trace(tag) << "Shared terms of " << theory->getId() << ": " << endl;
487 context::CDList<TNode>::const_iterator it = theory->shared_terms_begin(), it_end = theory->shared_terms_end();
488 for (unsigned i = 0; it != it_end; ++ it, ++i) {
489 Trace(tag) << "[" << i << "]: " << (*it) << endl;
490 }
491 }
492 }
493 }
494 }
495 }
496
497 void TheoryEngine::dumpAssertions(const char* tag) {
498 if (Dump.isOn(tag)) {
499 Dump(tag) << CommentCommand("Starting completeness check");
500 for (TheoryId theoryId = THEORY_FIRST; theoryId < THEORY_LAST; ++theoryId) {
501 Theory* theory = d_theoryTable[theoryId];
502 if (theory && d_logicInfo.isTheoryEnabled(theoryId)) {
503 Dump(tag) << CommentCommand("Completeness check");
504 Dump(tag) << PushCommand();
505
506 // Dump the shared terms
507 if (d_logicInfo.isSharingEnabled()) {
508 Dump(tag) << CommentCommand("Shared terms");
509 context::CDList<TNode>::const_iterator it = theory->shared_terms_begin(), it_end = theory->shared_terms_end();
510 for (unsigned i = 0; it != it_end; ++ it, ++i) {
511 stringstream ss;
512 ss << (*it);
513 Dump(tag) << CommentCommand(ss.str());
514 }
515 }
516
517 // Dump the assertions
518 Dump(tag) << CommentCommand("Assertions");
519 context::CDList<Assertion>::const_iterator it = theory->facts_begin(), it_end = theory->facts_end();
520 for (; it != it_end; ++ it) {
521 // Get the assertion
522 Node assertionNode = (*it).assertion;
523 // Purify all the terms
524
525 if ((*it).isPreregistered) {
526 Dump(tag) << CommentCommand("Preregistered");
527 } else {
528 Dump(tag) << CommentCommand("Shared assertion");
529 }
530 Dump(tag) << AssertCommand(assertionNode.toExpr());
531 }
532 Dump(tag) << CheckSatCommand();
533
534 Dump(tag) << PopCommand();
535 }
536 }
537 }
538 }
539
540 /**
541 * Check all (currently-active) theories for conflicts.
542 * @param effort the effort level to use
543 */
544 void TheoryEngine::check(Theory::Effort effort) {
545 // spendResource();
546
547 // Reset the interrupt flag
548 d_interrupted = false;
549
550 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
551 #undef CVC4_FOR_EACH_THEORY_STATEMENT
552 #endif
553 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
554 if (theory::TheoryTraits<THEORY>::hasCheck && d_logicInfo.isTheoryEnabled(THEORY)) { \
555 theoryOf(THEORY)->check(effort); \
556 if (d_inConflict) { \
557 Debug("conflict") << THEORY << " in conflict. " << std::endl; \
558 break; \
559 } \
560 }
561
562 // Do the checking
563 try {
564
565 // Mark the output channel unused (if this is FULL_EFFORT, and nothing
566 // is done by the theories, no additional check will be needed)
567 d_outputChannelUsed = false;
568
569 // Mark the lemmas flag (no lemmas added)
570 d_lemmasAdded = false;
571
572 Debug("theory") << "TheoryEngine::check(" << effort << "): d_factsAsserted = " << (d_factsAsserted ? "true" : "false") << endl;
573
574 // If in full effort, we have a fake new assertion just to jumpstart the checking
575 if (Theory::fullEffort(effort)) {
576 d_factsAsserted = true;
577 }
578
579 // Check until done
580 while (d_factsAsserted && !d_inConflict && !d_lemmasAdded) {
581
582 Debug("theory") << "TheoryEngine::check(" << effort << "): running check" << endl;
583
584 Trace("theory::assertions") << endl;
585 if (Trace.isOn("theory::assertions")) {
586 printAssertions("theory::assertions");
587 }
588
589 if(Theory::fullEffort(effort)) {
590 Trace("theory::assertions::fulleffort") << endl;
591 if (Trace.isOn("theory::assertions::fulleffort")) {
592 printAssertions("theory::assertions::fulleffort");
593 }
594 }
595
596 // Note that we've discharged all the facts
597 d_factsAsserted = false;
598
599 // Do the checking
600 CVC4_FOR_EACH_THEORY;
601
602 if(Dump.isOn("missed-t-conflicts")) {
603 Dump("missed-t-conflicts")
604 << CommentCommand("Completeness check for T-conflicts; expect sat")
605 << CheckSatCommand();
606 }
607
608 Debug("theory") << "TheoryEngine::check(" << effort << "): running propagation after the initial check" << endl;
609
610 // We are still satisfiable, propagate as much as possible
611 propagate(effort);
612
613 // We do combination if all has been processed and we are in fullcheck
614 if (Theory::fullEffort(effort) && d_logicInfo.isSharingEnabled() && !d_factsAsserted && !d_lemmasAdded && !d_inConflict) {
615 // Do the combination
616 Debug("theory") << "TheoryEngine::check(" << effort << "): running combination" << endl;
617 combineTheories();
618 if(d_logicInfo.isQuantified()){
619 d_quantEngine->notifyCombineTheories();
620 }
621 }
622 }
623
624 // Must consult quantifiers theory for last call to ensure sat, or otherwise add a lemma
625 if( Theory::fullEffort(effort) && ! d_inConflict && ! needCheck() ) {
626 Trace("theory::assertions-model") << endl;
627 if (Trace.isOn("theory::assertions-model")) {
628 printAssertions("theory::assertions-model");
629 }
630 //checks for theories requiring the model go at last call
631 d_curr_model->reset();
632 for (TheoryId theoryId = THEORY_FIRST; theoryId < THEORY_LAST; ++theoryId) {
633 if( theoryId!=THEORY_QUANTIFIERS ){
634 Theory* theory = d_theoryTable[theoryId];
635 if (theory && d_logicInfo.isTheoryEnabled(theoryId)) {
636 if( theory->needsCheckLastEffort() ){
637 if( !d_curr_model->isBuilt() ){
638 if( !d_curr_model_builder->buildModel(d_curr_model) ){
639 break;
640 }
641 }
642 theory->check(Theory::EFFORT_LAST_CALL);
643 }
644 }
645 }
646 }
647 if (!d_inConflict)
648 {
649 if(d_logicInfo.isQuantified()) {
650 // quantifiers engine must check at last call effort
651 d_quantEngine->check(Theory::EFFORT_LAST_CALL);
652 }
653 }
654 if (!d_inConflict && !needCheck())
655 {
656 // If d_eager_model_building is false, then we only mark that we
657 // are in "SAT mode". We build the model later only if the user asks
658 // for it via getBuiltModel.
659 d_inSatMode = true;
660 if (d_eager_model_building && !d_curr_model->isBuilt())
661 {
662 d_curr_model_builder->buildModel(d_curr_model);
663 }
664 }
665 }
666
667 Debug("theory") << "TheoryEngine::check(" << effort << "): done, we are " << (d_inConflict ? "unsat" : "sat") << (d_lemmasAdded ? " with new lemmas" : " with no new lemmas");
668 Debug("theory") << ", need check = " << (needCheck() ? "YES" : "NO") << endl;
669
670 if( Theory::fullEffort(effort) && !d_inConflict && !needCheck()) {
671 // case where we are about to answer SAT
672 if( d_masterEqualityEngine != NULL ){
673 AlwaysAssert(d_masterEqualityEngine->consistent());
674 }
675 if (d_curr_model->isBuilt())
676 {
677 // model construction should always succeed unless lemmas were added
678 AlwaysAssert(d_curr_model->isBuiltSuccess());
679 if (options::produceModels())
680 {
681 // Do post-processing of model from the theories (used for THEORY_SEP
682 // to construct heap model)
683 postProcessModel(d_curr_model);
684 // also call the model builder's post-process model
685 d_curr_model_builder->postProcessModel(d_incomplete.get(),
686 d_curr_model);
687 }
688 }
689 }
690 } catch(const theory::Interrupted&) {
691 Trace("theory") << "TheoryEngine::check() => interrupted" << endl;
692 }
693 // If fulleffort, check all theories
694 if(Dump.isOn("theory::fullcheck") && Theory::fullEffort(effort)) {
695 if (!d_inConflict && !needCheck()) {
696 dumpAssertions("theory::fullcheck");
697 }
698 }
699 }
700
701 void TheoryEngine::combineTheories() {
702
703 Trace("combineTheories") << "TheoryEngine::combineTheories()" << endl;
704
705 TimerStat::CodeTimer combineTheoriesTimer(d_combineTheoriesTime);
706
707 // Care graph we'll be building
708 CareGraph careGraph;
709
710 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
711 #undef CVC4_FOR_EACH_THEORY_STATEMENT
712 #endif
713 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
714 if (theory::TheoryTraits<THEORY>::isParametric && d_logicInfo.isTheoryEnabled(THEORY)) { \
715 theoryOf(THEORY)->getCareGraph(&careGraph); \
716 }
717
718 // Call on each parametric theory to give us its care graph
719 CVC4_FOR_EACH_THEORY;
720
721 Trace("combineTheories") << "TheoryEngine::combineTheories(): care graph size = " << careGraph.size() << endl;
722
723 // Now add splitters for the ones we are interested in
724 CareGraph::const_iterator care_it = careGraph.begin();
725 CareGraph::const_iterator care_it_end = careGraph.end();
726
727 for (; care_it != care_it_end; ++ care_it) {
728 const CarePair& carePair = *care_it;
729
730 Debug("combineTheories") << "TheoryEngine::combineTheories(): checking " << carePair.a << " = " << carePair.b << " from " << carePair.theory << endl;
731
732 Assert(d_sharedTerms.isShared(carePair.a) || carePair.a.isConst());
733 Assert(d_sharedTerms.isShared(carePair.b) || carePair.b.isConst());
734
735 // The equality in question (order for no repetition)
736 Node equality = carePair.a.eqNode(carePair.b);
737 // EqualityStatus es = getEqualityStatus(carePair.a, carePair.b);
738 // Debug("combineTheories") << "TheoryEngine::combineTheories(): " <<
739 // (es == EQUALITY_TRUE_AND_PROPAGATED ? "EQUALITY_TRUE_AND_PROPAGATED" :
740 // es == EQUALITY_FALSE_AND_PROPAGATED ? "EQUALITY_FALSE_AND_PROPAGATED" :
741 // es == EQUALITY_TRUE ? "EQUALITY_TRUE" :
742 // es == EQUALITY_FALSE ? "EQUALITY_FALSE" :
743 // es == EQUALITY_TRUE_IN_MODEL ? "EQUALITY_TRUE_IN_MODEL" :
744 // es == EQUALITY_FALSE_IN_MODEL ? "EQUALITY_FALSE_IN_MODEL" :
745 // es == EQUALITY_UNKNOWN ? "EQUALITY_UNKNOWN" :
746 // "Unexpected case") << endl;
747
748 // We need to split on it
749 Debug("combineTheories") << "TheoryEngine::combineTheories(): requesting a split " << endl;
750
751 lemma(equality.orNode(equality.notNode()), RULE_INVALID, false, false, false, carePair.theory);
752
753 // This code is supposed to force preference to follow what the theory models already have
754 // but it doesn't seem to make a big difference - need to explore more -Clark
755 // if (true) {
756 // if (es == EQUALITY_TRUE || es == EQUALITY_TRUE_IN_MODEL) {
757 Node e = ensureLiteral(equality);
758 d_propEngine->requirePhase(e, true);
759 // }
760 // else if (es == EQUALITY_FALSE_IN_MODEL) {
761 // Node e = ensureLiteral(equality);
762 // d_propEngine->requirePhase(e, false);
763 // }
764 // }
765 }
766 }
767
768 void TheoryEngine::propagate(Theory::Effort effort) {
769 // Reset the interrupt flag
770 d_interrupted = false;
771
772 // Definition of the statement that is to be run by every theory
773 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
774 #undef CVC4_FOR_EACH_THEORY_STATEMENT
775 #endif
776 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
777 if (theory::TheoryTraits<THEORY>::hasPropagate && d_logicInfo.isTheoryEnabled(THEORY)) { \
778 theoryOf(THEORY)->propagate(effort); \
779 }
780
781 // Reset the interrupt flag
782 d_interrupted = false;
783
784 // Propagate for each theory using the statement above
785 CVC4_FOR_EACH_THEORY;
786
787 if(Dump.isOn("missed-t-propagations")) {
788 for(unsigned i = 0; i < d_possiblePropagations.size(); ++i) {
789 Node atom = d_possiblePropagations[i];
790 bool value;
791 if(d_propEngine->hasValue(atom, value)) {
792 continue;
793 }
794 // Doesn't have a value, check it (and the negation)
795 if(d_hasPropagated.find(atom) == d_hasPropagated.end()) {
796 Dump("missed-t-propagations")
797 << CommentCommand("Completeness check for T-propagations; expect invalid")
798 << EchoCommand(atom.toString())
799 << QueryCommand(atom.toExpr())
800 << EchoCommand(atom.notNode().toString())
801 << QueryCommand(atom.notNode().toExpr());
802 }
803 }
804 }
805 }
806
807 Node TheoryEngine::getNextDecisionRequest()
808 {
809 return d_decManager->getNextDecisionRequest();
810 }
811
812 bool TheoryEngine::properConflict(TNode conflict) const {
813 bool value;
814 if (conflict.getKind() == kind::AND) {
815 for (unsigned i = 0; i < conflict.getNumChildren(); ++ i) {
816 if (! getPropEngine()->hasValue(conflict[i], value)) {
817 Debug("properConflict") << "Bad conflict is due to unassigned atom: "
818 << conflict[i] << endl;
819 return false;
820 }
821 if (! value) {
822 Debug("properConflict") << "Bad conflict is due to false atom: "
823 << conflict[i] << endl;
824 return false;
825 }
826 if (conflict[i] != Rewriter::rewrite(conflict[i])) {
827 Debug("properConflict") << "Bad conflict is due to atom not in normal form: "
828 << conflict[i] << " vs " << Rewriter::rewrite(conflict[i]) << endl;
829 return false;
830 }
831 }
832 } else {
833 if (! getPropEngine()->hasValue(conflict, value)) {
834 Debug("properConflict") << "Bad conflict is due to unassigned atom: "
835 << conflict << endl;
836 return false;
837 }
838 if(! value) {
839 Debug("properConflict") << "Bad conflict is due to false atom: "
840 << conflict << endl;
841 return false;
842 }
843 if (conflict != Rewriter::rewrite(conflict)) {
844 Debug("properConflict") << "Bad conflict is due to atom not in normal form: "
845 << conflict << " vs " << Rewriter::rewrite(conflict) << endl;
846 return false;
847 }
848 }
849 return true;
850 }
851
852 bool TheoryEngine::properPropagation(TNode lit) const {
853 if(!getPropEngine()->isSatLiteral(lit)) {
854 return false;
855 }
856 bool b;
857 return !getPropEngine()->hasValue(lit, b);
858 }
859
860 bool TheoryEngine::properExplanation(TNode node, TNode expl) const {
861 // Explanation must be either a conjunction of true literals that have true SAT values already
862 // or a singled literal that has a true SAT value already.
863 if (expl.getKind() == kind::AND) {
864 for (unsigned i = 0; i < expl.getNumChildren(); ++ i) {
865 bool value;
866 if (!d_propEngine->hasValue(expl[i], value) || !value) {
867 return false;
868 }
869 }
870 } else {
871 bool value;
872 return d_propEngine->hasValue(expl, value) && value;
873 }
874 return true;
875 }
876
877 bool TheoryEngine::collectModelInfo(theory::TheoryModel* m)
878 {
879 //have shared term engine collectModelInfo
880 // d_sharedTerms.collectModelInfo( m );
881 // Consult each active theory to get all relevant information
882 // concerning the model.
883 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId < theory::THEORY_LAST; ++theoryId) {
884 if(d_logicInfo.isTheoryEnabled(theoryId)) {
885 Trace("model-builder") << " CollectModelInfo on theory: " << theoryId << endl;
886 if (!d_theoryTable[theoryId]->collectModelInfo(m))
887 {
888 return false;
889 }
890 }
891 }
892 Trace("model-builder") << " CollectModelInfo boolean variables" << std::endl;
893 // Get the Boolean variables
894 vector<TNode> boolVars;
895 d_propEngine->getBooleanVariables(boolVars);
896 vector<TNode>::iterator it, iend = boolVars.end();
897 bool hasValue, value;
898 for (it = boolVars.begin(); it != iend; ++it) {
899 TNode var = *it;
900 hasValue = d_propEngine->hasValue(var, value);
901 // TODO: Assert that hasValue is true?
902 if (!hasValue) {
903 Trace("model-builder-assertions")
904 << " has no value : " << var << std::endl;
905 value = false;
906 }
907 Trace("model-builder-assertions") << "(assert" << (value ? " " : " (not ") << var << (value ? ");" : "));") << endl;
908 if (!m->assertPredicate(var, value))
909 {
910 return false;
911 }
912 }
913 return true;
914 }
915
916 void TheoryEngine::postProcessModel( theory::TheoryModel* m ){
917 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId < theory::THEORY_LAST; ++theoryId) {
918 if(d_logicInfo.isTheoryEnabled(theoryId)) {
919 Trace("model-builder-debug") << " PostProcessModel on theory: " << theoryId << endl;
920 d_theoryTable[theoryId]->postProcessModel( m );
921 }
922 }
923 }
924
925 TheoryModel* TheoryEngine::getModel() {
926 return d_curr_model;
927 }
928
929 TheoryModel* TheoryEngine::getBuiltModel()
930 {
931 if (!d_curr_model->isBuilt())
932 {
933 // If this method was called, we should be in SAT mode, and produceModels
934 // should be true.
935 AlwaysAssert(options::produceModels());
936 if (!d_inSatMode)
937 {
938 // not available, perhaps due to interuption.
939 return nullptr;
940 }
941 // must build model at this point
942 d_curr_model_builder->buildModel(d_curr_model);
943 }
944 return d_curr_model;
945 }
946
947 void TheoryEngine::getSynthSolutions(std::map<Node, Node>& sol_map)
948 {
949 if (d_quantEngine)
950 {
951 d_quantEngine->getSynthSolutions(sol_map);
952 }
953 else
954 {
955 Assert(false);
956 }
957 }
958
959 bool TheoryEngine::presolve() {
960 // Reset the interrupt flag
961 d_interrupted = false;
962
963 // Reset the decision manager. This clears its decision strategies that are
964 // no longer valid in this user context.
965 d_decManager->presolve();
966
967 try {
968 // Definition of the statement that is to be run by every theory
969 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
970 #undef CVC4_FOR_EACH_THEORY_STATEMENT
971 #endif
972 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
973 if (theory::TheoryTraits<THEORY>::hasPresolve) { \
974 theoryOf(THEORY)->presolve(); \
975 if(d_inConflict) { \
976 return true; \
977 } \
978 }
979
980 // Presolve for each theory using the statement above
981 CVC4_FOR_EACH_THEORY;
982 } catch(const theory::Interrupted&) {
983 Trace("theory") << "TheoryEngine::presolve() => interrupted" << endl;
984 }
985 // return whether we have a conflict
986 return false;
987 }/* TheoryEngine::presolve() */
988
989 void TheoryEngine::postsolve() {
990 // no longer in SAT mode
991 d_inSatMode = false;
992 // Reset the interrupt flag
993 d_interrupted = false;
994 bool CVC4_UNUSED wasInConflict = d_inConflict;
995
996 try {
997 // Definition of the statement that is to be run by every theory
998 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
999 #undef CVC4_FOR_EACH_THEORY_STATEMENT
1000 #endif
1001 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
1002 if (theory::TheoryTraits<THEORY>::hasPostsolve) \
1003 { \
1004 theoryOf(THEORY)->postsolve(); \
1005 Assert(!d_inConflict || wasInConflict) \
1006 << "conflict raised during postsolve()"; \
1007 }
1008
1009 // Postsolve for each theory using the statement above
1010 CVC4_FOR_EACH_THEORY;
1011 } catch(const theory::Interrupted&) {
1012 Trace("theory") << "TheoryEngine::postsolve() => interrupted" << endl;
1013 }
1014 }/* TheoryEngine::postsolve() */
1015
1016
1017 void TheoryEngine::notifyRestart() {
1018 // Reset the interrupt flag
1019 d_interrupted = false;
1020
1021 // Definition of the statement that is to be run by every theory
1022 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
1023 #undef CVC4_FOR_EACH_THEORY_STATEMENT
1024 #endif
1025 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
1026 if (theory::TheoryTraits<THEORY>::hasNotifyRestart && d_logicInfo.isTheoryEnabled(THEORY)) { \
1027 theoryOf(THEORY)->notifyRestart(); \
1028 }
1029
1030 // notify each theory using the statement above
1031 CVC4_FOR_EACH_THEORY;
1032 }
1033
1034 void TheoryEngine::ppStaticLearn(TNode in, NodeBuilder<>& learned) {
1035 // Reset the interrupt flag
1036 d_interrupted = false;
1037
1038 // Definition of the statement that is to be run by every theory
1039 #ifdef CVC4_FOR_EACH_THEORY_STATEMENT
1040 #undef CVC4_FOR_EACH_THEORY_STATEMENT
1041 #endif
1042 #define CVC4_FOR_EACH_THEORY_STATEMENT(THEORY) \
1043 if (theory::TheoryTraits<THEORY>::hasPpStaticLearn) { \
1044 theoryOf(THEORY)->ppStaticLearn(in, learned); \
1045 }
1046
1047 // static learning for each theory using the statement above
1048 CVC4_FOR_EACH_THEORY;
1049 }
1050
1051 void TheoryEngine::shutdown() {
1052 // Set this first; if a Theory shutdown() throws an exception,
1053 // at least the destruction of the TheoryEngine won't confound
1054 // matters.
1055 d_hasShutDown = true;
1056
1057 // Shutdown all the theories
1058 for(TheoryId theoryId = theory::THEORY_FIRST; theoryId < theory::THEORY_LAST; ++theoryId) {
1059 if(d_theoryTable[theoryId]) {
1060 theoryOf(theoryId)->shutdown();
1061 }
1062 }
1063
1064 d_ppCache.clear();
1065 }
1066
1067 theory::Theory::PPAssertStatus TheoryEngine::solve(TNode literal, SubstitutionMap& substitutionOut) {
1068 // Reset the interrupt flag
1069 d_interrupted = false;
1070
1071 TNode atom = literal.getKind() == kind::NOT ? literal[0] : literal;
1072 Trace("theory::solve") << "TheoryEngine::solve(" << literal << "): solving with " << theoryOf(atom)->getId() << endl;
1073
1074 if(! d_logicInfo.isTheoryEnabled(Theory::theoryOf(atom)) &&
1075 Theory::theoryOf(atom) != THEORY_SAT_SOLVER) {
1076 stringstream ss;
1077 ss << "The logic was specified as " << d_logicInfo.getLogicString()
1078 << ", which doesn't include " << Theory::theoryOf(atom)
1079 << ", but got a preprocessing-time fact for that theory." << endl
1080 << "The fact:" << endl
1081 << literal;
1082 throw LogicException(ss.str());
1083 }
1084
1085 Theory::PPAssertStatus solveStatus = theoryOf(atom)->ppAssert(literal, substitutionOut);
1086 Trace("theory::solve") << "TheoryEngine::solve(" << literal << ") => " << solveStatus << endl;
1087 return solveStatus;
1088 }
1089
1090 // Recursively traverse a term and call the theory rewriter on its sub-terms
1091 Node TheoryEngine::ppTheoryRewrite(TNode term) {
1092 NodeMap::iterator find = d_ppCache.find(term);
1093 if (find != d_ppCache.end()) {
1094 return (*find).second;
1095 }
1096 unsigned nc = term.getNumChildren();
1097 if (nc == 0) {
1098 return theoryOf(term)->ppRewrite(term);
1099 }
1100 Trace("theory-pp") << "ppTheoryRewrite { " << term << endl;
1101
1102 Node newTerm;
1103 // do not rewrite inside quantifiers
1104 if (term.isClosure())
1105 {
1106 newTerm = Rewriter::rewrite(term);
1107 }
1108 else
1109 {
1110 NodeBuilder<> newNode(term.getKind());
1111 if (term.getMetaKind() == kind::metakind::PARAMETERIZED) {
1112 newNode << term.getOperator();
1113 }
1114 unsigned i;
1115 for (i = 0; i < nc; ++i) {
1116 newNode << ppTheoryRewrite(term[i]);
1117 }
1118 newTerm = Rewriter::rewrite(Node(newNode));
1119 }
1120 Node newTerm2 = theoryOf(newTerm)->ppRewrite(newTerm);
1121 if (newTerm != newTerm2) {
1122 newTerm = ppTheoryRewrite(Rewriter::rewrite(newTerm2));
1123 }
1124 d_ppCache[term] = newTerm;
1125 Trace("theory-pp")<< "ppTheoryRewrite returning " << newTerm << "}" << endl;
1126 return newTerm;
1127 }
1128
1129
1130 void TheoryEngine::preprocessStart()
1131 {
1132 d_ppCache.clear();
1133 }
1134
1135
1136 struct preprocess_stack_element {
1137 TNode node;
1138 bool children_added;
1139 preprocess_stack_element(TNode node)
1140 : node(node), children_added(false) {}
1141 };/* struct preprocess_stack_element */
1142
1143
1144 Node TheoryEngine::preprocess(TNode assertion) {
1145
1146 Trace("theory::preprocess") << "TheoryEngine::preprocess(" << assertion << ")" << endl;
1147 // spendResource();
1148
1149 // Do a topological sort of the subexpressions and substitute them
1150 vector<preprocess_stack_element> toVisit;
1151 toVisit.push_back(assertion);
1152
1153 while (!toVisit.empty())
1154 {
1155 // The current node we are processing
1156 preprocess_stack_element& stackHead = toVisit.back();
1157 TNode current = stackHead.node;
1158
1159 Debug("theory::internal") << "TheoryEngine::preprocess(" << assertion << "): processing " << current << endl;
1160
1161 // If node already in the cache we're done, pop from the stack
1162 NodeMap::iterator find = d_ppCache.find(current);
1163 if (find != d_ppCache.end()) {
1164 toVisit.pop_back();
1165 continue;
1166 }
1167
1168 if(! d_logicInfo.isTheoryEnabled(Theory::theoryOf(current)) &&
1169 Theory::theoryOf(current) != THEORY_SAT_SOLVER) {
1170 stringstream ss;
1171 ss << "The logic was specified as " << d_logicInfo.getLogicString()
1172 << ", which doesn't include " << Theory::theoryOf(current)
1173 << ", but got a preprocessing-time fact for that theory." << endl
1174 << "The fact:" << endl
1175 << current;
1176 throw LogicException(ss.str());
1177 }
1178
1179 // If this is an atom, we preprocess its terms with the theory ppRewriter
1180 if (Theory::theoryOf(current) != THEORY_BOOL) {
1181 Node ppRewritten = ppTheoryRewrite(current);
1182 d_ppCache[current] = ppRewritten;
1183 Assert(Rewriter::rewrite(d_ppCache[current]) == d_ppCache[current]);
1184 continue;
1185 }
1186
1187 // Not yet substituted, so process
1188 if (stackHead.children_added) {
1189 // Children have been processed, so substitute
1190 NodeBuilder<> builder(current.getKind());
1191 if (current.getMetaKind() == kind::metakind::PARAMETERIZED) {
1192 builder << current.getOperator();
1193 }
1194 for (unsigned i = 0; i < current.getNumChildren(); ++ i) {
1195 Assert(d_ppCache.find(current[i]) != d_ppCache.end());
1196 builder << d_ppCache[current[i]];
1197 }
1198 // Mark the substitution and continue
1199 Node result = builder;
1200 if (result != current) {
1201 result = Rewriter::rewrite(result);
1202 }
1203 Debug("theory::internal") << "TheoryEngine::preprocess(" << assertion << "): setting " << current << " -> " << result << endl;
1204 d_ppCache[current] = result;
1205 toVisit.pop_back();
1206 } else {
1207 // Mark that we have added the children if any
1208 if (current.getNumChildren() > 0) {
1209 stackHead.children_added = true;
1210 // We need to add the children
1211 for(TNode::iterator child_it = current.begin(); child_it != current.end(); ++ child_it) {
1212 TNode childNode = *child_it;
1213 NodeMap::iterator childFind = d_ppCache.find(childNode);
1214 if (childFind == d_ppCache.end()) {
1215 toVisit.push_back(childNode);
1216 }
1217 }
1218 } else {
1219 // No children, so we're done
1220 Debug("substitution::internal") << "SubstitutionMap::internalSubstitute(" << assertion << "): setting " << current << " -> " << current << endl;
1221 d_ppCache[current] = current;
1222 toVisit.pop_back();
1223 }
1224 }
1225 }
1226
1227 // Return the substituted version
1228 return d_ppCache[assertion];
1229 }
1230
1231 void TheoryEngine::notifyPreprocessedAssertions(
1232 const std::vector<Node>& assertions) {
1233 // call all the theories
1234 for (TheoryId theoryId = theory::THEORY_FIRST; theoryId < theory::THEORY_LAST;
1235 ++theoryId) {
1236 if (d_theoryTable[theoryId]) {
1237 theoryOf(theoryId)->ppNotifyAssertions(assertions);
1238 }
1239 }
1240 }
1241
1242 bool TheoryEngine::markPropagation(TNode assertion, TNode originalAssertion, theory::TheoryId toTheoryId, theory::TheoryId fromTheoryId) {
1243
1244 // What and where we are asserting
1245 NodeTheoryPair toAssert(assertion, toTheoryId, d_propagationMapTimestamp);
1246 // What and where it came from
1247 NodeTheoryPair toExplain(originalAssertion, fromTheoryId, d_propagationMapTimestamp);
1248
1249 // See if the theory already got this literal
1250 PropagationMap::const_iterator find = d_propagationMap.find(toAssert);
1251 if (find != d_propagationMap.end()) {
1252 // The theory already knows this
1253 Trace("theory::assertToTheory") << "TheoryEngine::markPropagation(): already there" << endl;
1254 return false;
1255 }
1256
1257 Trace("theory::assertToTheory") << "TheoryEngine::markPropagation(): marking [" << d_propagationMapTimestamp << "] " << assertion << ", " << toTheoryId << " from " << originalAssertion << ", " << fromTheoryId << endl;
1258
1259 // Mark the propagation
1260 d_propagationMap[toAssert] = toExplain;
1261 d_propagationMapTimestamp = d_propagationMapTimestamp + 1;
1262
1263 return true;
1264 }
1265
1266
1267 void TheoryEngine::assertToTheory(TNode assertion, TNode originalAssertion, theory::TheoryId toTheoryId, theory::TheoryId fromTheoryId) {
1268
1269 Trace("theory::assertToTheory") << "TheoryEngine::assertToTheory(" << assertion << ", " << originalAssertion << "," << toTheoryId << ", " << fromTheoryId << ")" << endl;
1270
1271 Assert(toTheoryId != fromTheoryId);
1272 if(toTheoryId != THEORY_SAT_SOLVER &&
1273 ! d_logicInfo.isTheoryEnabled(toTheoryId)) {
1274 stringstream ss;
1275 ss << "The logic was specified as " << d_logicInfo.getLogicString()
1276 << ", which doesn't include " << toTheoryId
1277 << ", but got an asserted fact to that theory." << endl
1278 << "The fact:" << endl
1279 << assertion;
1280 throw LogicException(ss.str());
1281 }
1282
1283 if (d_inConflict) {
1284 return;
1285 }
1286
1287 // If sharing is disabled, things are easy
1288 if (!d_logicInfo.isSharingEnabled()) {
1289 Assert(assertion == originalAssertion);
1290 if (fromTheoryId == THEORY_SAT_SOLVER) {
1291 // Send to the apropriate theory
1292 theory::Theory* toTheory = theoryOf(toTheoryId);
1293 // We assert it, and we know it's preregistereed
1294 toTheory->assertFact(assertion, true);
1295 // Mark that we have more information
1296 d_factsAsserted = true;
1297 } else {
1298 Assert(toTheoryId == THEORY_SAT_SOLVER);
1299 // Check for propositional conflict
1300 bool value;
1301 if (d_propEngine->hasValue(assertion, value)) {
1302 if (!value) {
1303 Trace("theory::propagate") << "TheoryEngine::assertToTheory(" << assertion << ", " << toTheoryId << ", " << fromTheoryId << "): conflict (no sharing)" << endl;
1304 d_inConflict = true;
1305 } else {
1306 return;
1307 }
1308 }
1309 d_propagatedLiterals.push_back(assertion);
1310 }
1311 return;
1312 }
1313
1314 // Polarity of the assertion
1315 bool polarity = assertion.getKind() != kind::NOT;
1316
1317 // Atom of the assertion
1318 TNode atom = polarity ? assertion : assertion[0];
1319
1320 // If sending to the shared terms database, it's also simple
1321 if (toTheoryId == THEORY_BUILTIN) {
1322 Assert(atom.getKind() == kind::EQUAL)
1323 << "atom should be an EQUALity, not `" << atom << "'";
1324 if (markPropagation(assertion, originalAssertion, toTheoryId, fromTheoryId)) {
1325 d_sharedTerms.assertEquality(atom, polarity, assertion);
1326 }
1327 return;
1328 }
1329
1330 // Things from the SAT solver are already normalized, so they go
1331 // directly to the apropriate theory
1332 if (fromTheoryId == THEORY_SAT_SOLVER) {
1333 // We know that this is normalized, so just send it off to the theory
1334 if (markPropagation(assertion, originalAssertion, toTheoryId, fromTheoryId)) {
1335 // Is it preregistered
1336 bool preregistered = d_propEngine->isSatLiteral(assertion) && Theory::theoryOf(assertion) == toTheoryId;
1337 // We assert it
1338 theoryOf(toTheoryId)->assertFact(assertion, preregistered);
1339 // Mark that we have more information
1340 d_factsAsserted = true;
1341 }
1342 return;
1343 }
1344
1345 // Propagations to the SAT solver are just enqueued for pickup by
1346 // the SAT solver later
1347 if (toTheoryId == THEORY_SAT_SOLVER) {
1348 if (markPropagation(assertion, originalAssertion, toTheoryId, fromTheoryId)) {
1349 // Enqueue for propagation to the SAT solver
1350 d_propagatedLiterals.push_back(assertion);
1351 // Check for propositional conflicts
1352 bool value;
1353 if (d_propEngine->hasValue(assertion, value) && !value) {
1354 Trace("theory::propagate") << "TheoryEngine::assertToTheory(" << assertion << ", " << toTheoryId << ", " << fromTheoryId << "): conflict (sharing)" << endl;
1355 d_inConflict = true;
1356 }
1357 }
1358 return;
1359 }
1360
1361 Assert(atom.getKind() == kind::EQUAL);
1362
1363 // Normalize
1364 Node normalizedLiteral = Rewriter::rewrite(assertion);
1365
1366 // See if it rewrites false directly -> conflict
1367 if (normalizedLiteral.isConst()) {
1368 if (!normalizedLiteral.getConst<bool>()) {
1369 // Mark the propagation for explanations
1370 if (markPropagation(normalizedLiteral, originalAssertion, toTheoryId, fromTheoryId)) {
1371 // Get the explanation (conflict will figure out where it came from)
1372 conflict(normalizedLiteral, toTheoryId);
1373 } else {
1374 Unreachable();
1375 }
1376 return;
1377 }
1378 }
1379
1380 // Try and assert (note that we assert the non-normalized one)
1381 if (markPropagation(assertion, originalAssertion, toTheoryId, fromTheoryId)) {
1382 // Check if has been pre-registered with the theory
1383 bool preregistered = d_propEngine->isSatLiteral(assertion) && Theory::theoryOf(assertion) == toTheoryId;
1384 // Assert away
1385 theoryOf(toTheoryId)->assertFact(assertion, preregistered);
1386 d_factsAsserted = true;
1387 }
1388
1389 return;
1390 }
1391
1392 void TheoryEngine::assertFact(TNode literal)
1393 {
1394 Trace("theory") << "TheoryEngine::assertFact(" << literal << ")" << endl;
1395
1396 // spendResource();
1397
1398 // If we're in conflict, nothing to do
1399 if (d_inConflict) {
1400 return;
1401 }
1402
1403 // Get the atom
1404 bool polarity = literal.getKind() != kind::NOT;
1405 TNode atom = polarity ? literal : literal[0];
1406
1407 if (d_logicInfo.isSharingEnabled()) {
1408
1409 // If any shared terms, it's time to do sharing work
1410 if (d_sharedTerms.hasSharedTerms(atom)) {
1411 // Notify the theories the shared terms
1412 SharedTermsDatabase::shared_terms_iterator it = d_sharedTerms.begin(atom);
1413 SharedTermsDatabase::shared_terms_iterator it_end = d_sharedTerms.end(atom);
1414 for (; it != it_end; ++ it) {
1415 TNode term = *it;
1416 Theory::Set theories = d_sharedTerms.getTheoriesToNotify(atom, term);
1417 for (TheoryId id = THEORY_FIRST; id != THEORY_LAST; ++ id) {
1418 if (Theory::setContains(id, theories)) {
1419 theoryOf(id)->addSharedTermInternal(term);
1420 }
1421 }
1422 d_sharedTerms.markNotified(term, theories);
1423 }
1424 }
1425
1426 // If it's an equality, assert it to the shared term manager, even though the terms are not
1427 // yet shared. As the terms become shared later, the shared terms manager will then add them
1428 // to the assert the equality to the interested theories
1429 if (atom.getKind() == kind::EQUAL) {
1430 // Assert it to the the owning theory
1431 assertToTheory(literal, literal, /* to */ Theory::theoryOf(atom), /* from */ THEORY_SAT_SOLVER);
1432 // Shared terms manager will assert to interested theories directly, as the terms become shared
1433 assertToTheory(literal, literal, /* to */ THEORY_BUILTIN, /* from */ THEORY_SAT_SOLVER);
1434
1435 // Now, let's check for any atom triggers from lemmas
1436 AtomRequests::atom_iterator it = d_atomRequests.getAtomIterator(atom);
1437 while (!it.done()) {
1438 const AtomRequests::Request& request = it.get();
1439 Node toAssert = polarity ? (Node) request.atom : request.atom.notNode();
1440 Debug("theory::atoms") << "TheoryEngine::assertFact(" << literal << "): sending requested " << toAssert << endl;
1441 assertToTheory(toAssert, literal, request.toTheory, THEORY_SAT_SOLVER);
1442 it.next();
1443 }
1444
1445 } else {
1446 // Not an equality, just assert to the appropriate theory
1447 assertToTheory(literal, literal, /* to */ Theory::theoryOf(atom), /* from */ THEORY_SAT_SOLVER);
1448 }
1449 } else {
1450 // Assert the fact to the appropriate theory directly
1451 assertToTheory(literal, literal, /* to */ Theory::theoryOf(atom), /* from */ THEORY_SAT_SOLVER);
1452 }
1453 }
1454
1455 bool TheoryEngine::propagate(TNode literal, theory::TheoryId theory) {
1456
1457 Debug("theory::propagate") << "TheoryEngine::propagate(" << literal << ", " << theory << ")" << endl;
1458
1459 // spendResource();
1460
1461 if(Dump.isOn("t-propagations")) {
1462 Dump("t-propagations") << CommentCommand("negation of theory propagation: expect valid")
1463 << QueryCommand(literal.toExpr());
1464 }
1465 if(Dump.isOn("missed-t-propagations")) {
1466 d_hasPropagated.insert(literal);
1467 }
1468
1469 // Get the atom
1470 bool polarity = literal.getKind() != kind::NOT;
1471 TNode atom = polarity ? literal : literal[0];
1472
1473 if (d_logicInfo.isSharingEnabled() && atom.getKind() == kind::EQUAL) {
1474 if (d_propEngine->isSatLiteral(literal)) {
1475 // We propagate SAT literals to SAT
1476 assertToTheory(literal, literal, /* to */ THEORY_SAT_SOLVER, /* from */ theory);
1477 }
1478 if (theory != THEORY_BUILTIN) {
1479 // Assert to the shared terms database
1480 assertToTheory(literal, literal, /* to */ THEORY_BUILTIN, /* from */ theory);
1481 }
1482 } else {
1483 // We could be propagating a unit-clause lemma. In this case, we need to provide a
1484 // recipe.
1485 // TODO: Consider putting this someplace else? This is the only refence to the proof
1486 // manager in this class.
1487
1488 PROOF({
1489 LemmaProofRecipe proofRecipe;
1490 proofRecipe.addBaseAssertion(literal);
1491
1492 Node emptyNode;
1493 LemmaProofRecipe::ProofStep proofStep(theory, emptyNode);
1494 proofStep.addAssertion(literal);
1495 proofRecipe.addStep(proofStep);
1496
1497 ProofManager::getCnfProof()->setProofRecipe(&proofRecipe);
1498 });
1499
1500 // Just send off to the SAT solver
1501 Assert(d_propEngine->isSatLiteral(literal));
1502 assertToTheory(literal, literal, /* to */ THEORY_SAT_SOLVER, /* from */ theory);
1503 }
1504
1505 return !d_inConflict;
1506 }
1507
1508 const LogicInfo& TheoryEngine::getLogicInfo() const { return d_logicInfo; }
1509
1510 theory::EqualityStatus TheoryEngine::getEqualityStatus(TNode a, TNode b) {
1511 Assert(a.getType().isComparableTo(b.getType()));
1512 if (d_sharedTerms.isShared(a) && d_sharedTerms.isShared(b)) {
1513 if (d_sharedTerms.areEqual(a,b)) {
1514 return EQUALITY_TRUE_AND_PROPAGATED;
1515 }
1516 else if (d_sharedTerms.areDisequal(a,b)) {
1517 return EQUALITY_FALSE_AND_PROPAGATED;
1518 }
1519 }
1520 return theoryOf(Theory::theoryOf(a.getType()))->getEqualityStatus(a, b);
1521 }
1522
1523 Node TheoryEngine::getModelValue(TNode var) {
1524 if (var.isConst())
1525 {
1526 // the model value of a constant must be itself
1527 return var;
1528 }
1529 Assert(d_sharedTerms.isShared(var));
1530 return theoryOf(Theory::theoryOf(var.getType()))->getModelValue(var);
1531 }
1532
1533
1534 Node TheoryEngine::ensureLiteral(TNode n) {
1535 Debug("ensureLiteral") << "rewriting: " << n << std::endl;
1536 Node rewritten = Rewriter::rewrite(n);
1537 Debug("ensureLiteral") << " got: " << rewritten << std::endl;
1538 Node preprocessed = preprocess(rewritten);
1539 Debug("ensureLiteral") << "preprocessed: " << preprocessed << std::endl;
1540 d_propEngine->ensureLiteral(preprocessed);
1541 return preprocessed;
1542 }
1543
1544
1545 void TheoryEngine::printInstantiations( std::ostream& out ) {
1546 if( d_quantEngine ){
1547 d_quantEngine->printInstantiations( out );
1548 }else{
1549 out << "Internal error : instantiations not available when quantifiers are not present." << std::endl;
1550 Assert(false);
1551 }
1552 }
1553
1554 void TheoryEngine::printSynthSolution( std::ostream& out ) {
1555 if( d_quantEngine ){
1556 d_quantEngine->printSynthSolution( out );
1557 }else{
1558 out << "Internal error : synth solution not available when quantifiers are not present." << std::endl;
1559 Assert(false);
1560 }
1561 }
1562
1563 void TheoryEngine::getInstantiatedQuantifiedFormulas( std::vector< Node >& qs ) {
1564 if( d_quantEngine ){
1565 d_quantEngine->getInstantiatedQuantifiedFormulas( qs );
1566 }else{
1567 Assert(false);
1568 }
1569 }
1570
1571 void TheoryEngine::getInstantiations( Node q, std::vector< Node >& insts ) {
1572 if( d_quantEngine ){
1573 d_quantEngine->getInstantiations( q, insts );
1574 }else{
1575 Assert(false);
1576 }
1577 }
1578
1579 void TheoryEngine::getInstantiationTermVectors( Node q, std::vector< std::vector< Node > >& tvecs ) {
1580 if( d_quantEngine ){
1581 d_quantEngine->getInstantiationTermVectors( q, tvecs );
1582 }else{
1583 Assert(false);
1584 }
1585 }
1586
1587 void TheoryEngine::getInstantiations( std::map< Node, std::vector< Node > >& insts ) {
1588 if( d_quantEngine ){
1589 d_quantEngine->getInstantiations( insts );
1590 }else{
1591 Assert(false);
1592 }
1593 }
1594
1595 void TheoryEngine::getInstantiationTermVectors( std::map< Node, std::vector< std::vector< Node > > >& insts ) {
1596 if( d_quantEngine ){
1597 d_quantEngine->getInstantiationTermVectors( insts );
1598 }else{
1599 Assert(false);
1600 }
1601 }
1602
1603 Node TheoryEngine::getInstantiatedConjunction( Node q ) {
1604 if( d_quantEngine ){
1605 return d_quantEngine->getInstantiatedConjunction( q );
1606 }else{
1607 Assert(false);
1608 return Node::null();
1609 }
1610 }
1611
1612
1613 static Node mkExplanation(const std::vector<NodeTheoryPair>& explanation) {
1614
1615 std::set<TNode> all;
1616 for (unsigned i = 0; i < explanation.size(); ++ i) {
1617 Assert(explanation[i].theory == THEORY_SAT_SOLVER);
1618 all.insert(explanation[i].node);
1619 }
1620
1621 if (all.size() == 0) {
1622 // Normalize to true
1623 return NodeManager::currentNM()->mkConst<bool>(true);
1624 }
1625
1626 if (all.size() == 1) {
1627 // All the same, or just one
1628 return explanation[0].node;
1629 }
1630
1631 NodeBuilder<> conjunction(kind::AND);
1632 std::set<TNode>::const_iterator it = all.begin();
1633 std::set<TNode>::const_iterator it_end = all.end();
1634 while (it != it_end) {
1635 conjunction << *it;
1636 ++ it;
1637 }
1638
1639 return conjunction;
1640 }
1641
1642 Node TheoryEngine::getExplanationAndRecipe(TNode node, LemmaProofRecipe* proofRecipe) {
1643 Debug("theory::explain") << "TheoryEngine::getExplanation(" << node << "): current propagation index = " << d_propagationMapTimestamp << endl;
1644
1645 bool polarity = node.getKind() != kind::NOT;
1646 TNode atom = polarity ? node : node[0];
1647
1648 // If we're not in shared mode, explanations are simple
1649 if (!d_logicInfo.isSharingEnabled()) {
1650 Debug("theory::explain") << "TheoryEngine::getExplanation: sharing is NOT enabled. "
1651 << " Responsible theory is: "
1652 << theoryOf(atom)->getId() << std::endl;
1653
1654 Node explanation = theoryOf(atom)->explain(node);
1655 Debug("theory::explain") << "TheoryEngine::getExplanation(" << node << ") => " << explanation << endl;
1656 PROOF({
1657 if(proofRecipe) {
1658 Node emptyNode;
1659 LemmaProofRecipe::ProofStep proofStep(theoryOf(atom)->getId(), emptyNode);
1660 proofStep.addAssertion(node);
1661 proofRecipe->addBaseAssertion(node);
1662
1663 if (explanation.getKind() == kind::AND) {
1664 // If the explanation is a conjunction, the recipe for the corresponding lemma is
1665 // the negation of its conjuncts.
1666 Node flat = flattenAnd(explanation);
1667 for (unsigned i = 0; i < flat.getNumChildren(); ++i) {
1668 if (flat[i].isConst() && flat[i].getConst<bool>()) {
1669 ++ i;
1670 continue;
1671 }
1672 if (flat[i].getKind() == kind::NOT &&
1673 flat[i][0].isConst() && !flat[i][0].getConst<bool>()) {
1674 ++ i;
1675 continue;
1676 }
1677 Debug("theory::explain") << "TheoryEngine::getExplanationAndRecipe: adding recipe assertion: "
1678 << flat[i].negate() << std::endl;
1679 proofStep.addAssertion(flat[i].negate());
1680 proofRecipe->addBaseAssertion(flat[i].negate());
1681 }
1682 } else {
1683 // The recipe for proving it is by negating it. "True" is not an acceptable reason.
1684 if (!((explanation.isConst() && explanation.getConst<bool>()) ||
1685 (explanation.getKind() == kind::NOT &&
1686 explanation[0].isConst() && !explanation[0].getConst<bool>()))) {
1687 proofStep.addAssertion(explanation.negate());
1688 proofRecipe->addBaseAssertion(explanation.negate());
1689 }
1690 }
1691
1692 proofRecipe->addStep(proofStep);
1693 }
1694 });
1695
1696 return explanation;
1697 }
1698
1699 Debug("theory::explain") << "TheoryEngine::getExplanation: sharing IS enabled" << std::endl;
1700
1701 // Initial thing to explain
1702 NodeTheoryPair toExplain(node, THEORY_SAT_SOLVER, d_propagationMapTimestamp);
1703 Assert(d_propagationMap.find(toExplain) != d_propagationMap.end());
1704
1705 NodeTheoryPair nodeExplainerPair = d_propagationMap[toExplain];
1706 Debug("theory::explain") << "TheoryEngine::getExplanation: explainer for node "
1707 << nodeExplainerPair.node
1708 << " is theory: " << nodeExplainerPair.theory << std::endl;
1709 TheoryId explainer = nodeExplainerPair.theory;
1710
1711 // Create the workplace for explanations
1712 std::vector<NodeTheoryPair> explanationVector;
1713 explanationVector.push_back(d_propagationMap[toExplain]);
1714 // Process the explanation
1715 if (proofRecipe) {
1716 Node emptyNode;
1717 LemmaProofRecipe::ProofStep proofStep(explainer, emptyNode);
1718 proofStep.addAssertion(node);
1719 proofRecipe->addStep(proofStep);
1720 proofRecipe->addBaseAssertion(node);
1721 }
1722
1723 getExplanation(explanationVector, proofRecipe);
1724 Node explanation = mkExplanation(explanationVector);
1725
1726 Debug("theory::explain") << "TheoryEngine::getExplanation(" << node << ") => " << explanation << endl;
1727
1728 return explanation;
1729 }
1730
1731 Node TheoryEngine::getExplanation(TNode node) {
1732 LemmaProofRecipe *dontCareRecipe = NULL;
1733 return getExplanationAndRecipe(node, dontCareRecipe);
1734 }
1735
1736 struct AtomsCollect {
1737
1738 std::vector<TNode> d_atoms;
1739 std::unordered_set<TNode, TNodeHashFunction> d_visited;
1740
1741 public:
1742
1743 typedef void return_type;
1744
1745 bool alreadyVisited(TNode current, TNode parent) {
1746 // Check if already visited
1747 if (d_visited.find(current) != d_visited.end()) return true;
1748 // Don't visit non-boolean
1749 if (!current.getType().isBoolean()) return true;
1750 // New node
1751 return false;
1752 }
1753
1754 void visit(TNode current, TNode parent) {
1755 if (Theory::theoryOf(current) != theory::THEORY_BOOL) {
1756 d_atoms.push_back(current);
1757 }
1758 d_visited.insert(current);
1759 }
1760
1761 void start(TNode node) {}
1762 void done(TNode node) {}
1763
1764 std::vector<TNode> getAtoms() const {
1765 return d_atoms;
1766 }
1767 };
1768
1769 void TheoryEngine::ensureLemmaAtoms(const std::vector<TNode>& atoms, theory::TheoryId atomsTo) {
1770 for (unsigned i = 0; i < atoms.size(); ++ i) {
1771
1772 // Non-equality atoms are either owned by theory or they don't make sense
1773 if (atoms[i].getKind() != kind::EQUAL) {
1774 continue;
1775 }
1776
1777 // The equality
1778 Node eq = atoms[i];
1779 // Simple normalization to not repeat stuff
1780 if (eq[0] > eq[1]) {
1781 eq = eq[1].eqNode(eq[0]);
1782 }
1783
1784 // Rewrite the equality
1785 Node eqNormalized = Rewriter::rewrite(atoms[i]);
1786
1787 Debug("theory::atoms") << "TheoryEngine::ensureLemmaAtoms(): " << eq << " with nf " << eqNormalized << endl;
1788
1789 // If the equality is a boolean constant, we send immediately
1790 if (eqNormalized.isConst()) {
1791 if (eqNormalized.getConst<bool>()) {
1792 assertToTheory(eq, eqNormalized, /** to */ atomsTo, /** Sat solver */ theory::THEORY_SAT_SOLVER);
1793 } else {
1794 assertToTheory(eq.notNode(), eqNormalized.notNode(), /** to */ atomsTo, /** Sat solver */ theory::THEORY_SAT_SOLVER);
1795 }
1796 continue;
1797 }else if( eqNormalized.getKind() != kind::EQUAL){
1798 Assert(eqNormalized.getKind() == kind::BOOLEAN_TERM_VARIABLE
1799 || (eqNormalized.getKind() == kind::NOT
1800 && eqNormalized[0].getKind() == kind::BOOLEAN_TERM_VARIABLE));
1801 // this happens for Boolean term equalities V = true that are rewritten to V, we should skip
1802 // TODO : revisit this
1803 continue;
1804 }
1805
1806 // If the normalization did the just flips, keep the flip
1807 if (eqNormalized[0] == eq[1] && eqNormalized[1] == eq[0]) {
1808 eq = eqNormalized;
1809 }
1810
1811 // Check if the equality is already known by the sat solver
1812 if (d_propEngine->isSatLiteral(eqNormalized)) {
1813 bool value;
1814 if (d_propEngine->hasValue(eqNormalized, value)) {
1815 if (value) {
1816 assertToTheory(eq, eqNormalized, atomsTo, theory::THEORY_SAT_SOLVER);
1817 continue;
1818 } else {
1819 assertToTheory(eq.notNode(), eqNormalized.notNode(), atomsTo, theory::THEORY_SAT_SOLVER);
1820 continue;
1821 }
1822 }
1823 }
1824
1825 // If the theory is asking about a different form, or the form is ok but if will go to a different theory
1826 // then we must figure it out
1827 if (eqNormalized != eq || Theory::theoryOf(eq) != atomsTo) {
1828 // If you get eqNormalized, send atoms[i] to atomsTo
1829 d_atomRequests.add(eqNormalized, eq, atomsTo);
1830 }
1831 }
1832 }
1833
1834 theory::LemmaStatus TheoryEngine::lemma(TNode node,
1835 ProofRule rule,
1836 bool negated,
1837 bool removable,
1838 bool preprocess,
1839 theory::TheoryId atomsTo) {
1840 // For resource-limiting (also does a time check).
1841 // spendResource();
1842
1843 // Do we need to check atoms
1844 if (atomsTo != theory::THEORY_LAST) {
1845 Debug("theory::atoms") << "TheoryEngine::lemma(" << node << ", " << atomsTo << ")" << endl;
1846 AtomsCollect collectAtoms;
1847 NodeVisitor<AtomsCollect>::run(collectAtoms, node);
1848 ensureLemmaAtoms(collectAtoms.getAtoms(), atomsTo);
1849 }
1850
1851 if(Dump.isOn("t-lemmas")) {
1852 Node n = node;
1853 if (negated) {
1854 n = node.negate();
1855 }
1856 Dump("t-lemmas") << CommentCommand("theory lemma: expect valid")
1857 << QueryCommand(n.toExpr());
1858 }
1859
1860 // Share with other portfolio threads
1861 if(d_channels->getLemmaOutputChannel() != NULL) {
1862 d_channels->getLemmaOutputChannel()->notifyNewLemma(node.toExpr());
1863 }
1864
1865 AssertionPipeline additionalLemmas;
1866
1867 // Run theory preprocessing, maybe
1868 Node ppNode = preprocess ? this->preprocess(node) : Node(node);
1869
1870 // Remove the ITEs
1871 Debug("ite") << "Remove ITE from " << ppNode << std::endl;
1872 additionalLemmas.push_back(ppNode);
1873 additionalLemmas.updateRealAssertionsEnd();
1874 d_tform_remover.run(additionalLemmas.ref(),
1875 additionalLemmas.getIteSkolemMap());
1876 Debug("ite") << "..done " << additionalLemmas[0] << std::endl;
1877 additionalLemmas.replace(0, theory::Rewriter::rewrite(additionalLemmas[0]));
1878
1879 if(Debug.isOn("lemma-ites")) {
1880 Debug("lemma-ites") << "removed ITEs from lemma: " << ppNode << endl;
1881 Debug("lemma-ites") << " + now have the following "
1882 << additionalLemmas.size() << " lemma(s):" << endl;
1883 for(std::vector<Node>::const_iterator i = additionalLemmas.begin();
1884 i != additionalLemmas.end();
1885 ++i) {
1886 Debug("lemma-ites") << " + " << *i << endl;
1887 }
1888 Debug("lemma-ites") << endl;
1889 }
1890
1891 // assert to prop engine
1892 d_propEngine->assertLemma(additionalLemmas[0], negated, removable, rule, node);
1893 for (unsigned i = 1; i < additionalLemmas.size(); ++ i) {
1894 additionalLemmas.replace(i, theory::Rewriter::rewrite(additionalLemmas[i]));
1895 d_propEngine->assertLemma(additionalLemmas[i], false, removable, rule, node);
1896 }
1897
1898 // WARNING: Below this point don't assume additionalLemmas[0] to be not negated.
1899 if(negated) {
1900 additionalLemmas.replace(0, additionalLemmas[0].notNode());
1901 negated = false;
1902 }
1903
1904 // assert to decision engine
1905 if(!removable) {
1906 d_decisionEngine->addAssertions(additionalLemmas);
1907 }
1908
1909 // Mark that we added some lemmas
1910 d_lemmasAdded = true;
1911
1912 // Lemma analysis isn't online yet; this lemma may only live for this
1913 // user level.
1914 return theory::LemmaStatus(additionalLemmas[0], d_userContext->getLevel());
1915 }
1916
1917 void TheoryEngine::conflict(TNode conflict, TheoryId theoryId) {
1918
1919 Debug("theory::conflict") << "TheoryEngine::conflict(" << conflict << ", " << theoryId << ")" << endl;
1920
1921 // Mark that we are in conflict
1922 d_inConflict = true;
1923
1924 if(Dump.isOn("t-conflicts")) {
1925 Dump("t-conflicts") << CommentCommand("theory conflict: expect unsat")
1926 << CheckSatCommand(conflict.toExpr());
1927 }
1928
1929 LemmaProofRecipe* proofRecipe = NULL;
1930 PROOF({
1931 proofRecipe = new LemmaProofRecipe;
1932 Node emptyNode;
1933 LemmaProofRecipe::ProofStep proofStep(theoryId, emptyNode);
1934
1935 if (conflict.getKind() == kind::AND) {
1936 for (unsigned i = 0; i < conflict.getNumChildren(); ++i) {
1937 proofStep.addAssertion(conflict[i].negate());
1938 }
1939 } else {
1940 proofStep.addAssertion(conflict.negate());
1941 }
1942
1943 proofRecipe->addStep(proofStep);
1944 });
1945
1946 // In the multiple-theories case, we need to reconstruct the conflict
1947 if (d_logicInfo.isSharingEnabled()) {
1948 // Create the workplace for explanations
1949 std::vector<NodeTheoryPair> explanationVector;
1950 explanationVector.push_back(NodeTheoryPair(conflict, theoryId, d_propagationMapTimestamp));
1951
1952 // Process the explanation
1953 getExplanation(explanationVector, proofRecipe);
1954 PROOF(ProofManager::getCnfProof()->setProofRecipe(proofRecipe));
1955 Node fullConflict = mkExplanation(explanationVector);
1956 Debug("theory::conflict") << "TheoryEngine::conflict(" << conflict << ", " << theoryId << "): full = " << fullConflict << endl;
1957 Assert(properConflict(fullConflict));
1958 lemma(fullConflict, RULE_CONFLICT, true, true, false, THEORY_LAST);
1959
1960 } else {
1961 // When only one theory, the conflict should need no processing
1962 Assert(properConflict(conflict));
1963 PROOF({
1964 if (conflict.getKind() == kind::AND) {
1965 // If the conflict is a conjunction, the corresponding lemma is derived by negating
1966 // its conjuncts.
1967 for (unsigned i = 0; i < conflict.getNumChildren(); ++i) {
1968 if (conflict[i].isConst() && conflict[i].getConst<bool>()) {
1969 ++ i;
1970 continue;
1971 }
1972 if (conflict[i].getKind() == kind::NOT &&
1973 conflict[i][0].isConst() && !conflict[i][0].getConst<bool>()) {
1974 ++ i;
1975 continue;
1976 }
1977 proofRecipe->getStep(0)->addAssertion(conflict[i].negate());
1978 proofRecipe->addBaseAssertion(conflict[i].negate());
1979 }
1980 } else {
1981 proofRecipe->getStep(0)->addAssertion(conflict.negate());
1982 proofRecipe->addBaseAssertion(conflict.negate());
1983 }
1984
1985 ProofManager::getCnfProof()->setProofRecipe(proofRecipe);
1986 });
1987
1988 lemma(conflict, RULE_CONFLICT, true, true, false, THEORY_LAST);
1989 }
1990
1991 PROOF({
1992 delete proofRecipe;
1993 proofRecipe = NULL;
1994 });
1995 }
1996
1997 void TheoryEngine::staticInitializeBVOptions(
1998 const std::vector<Node>& assertions)
1999 {
2000 bool useSlicer = true;
2001 if (options::bitvectorEqualitySlicer() == bv::BITVECTOR_SLICER_ON)
2002 {
2003 if (!d_logicInfo.isPure(theory::THEORY_BV) || d_logicInfo.isQuantified())
2004 throw ModalException(
2005 "Slicer currently only supports pure QF_BV formulas. Use "
2006 "--bv-eq-slicer=off");
2007 if (options::incrementalSolving())
2008 throw ModalException(
2009 "Slicer does not currently support incremental mode. Use "
2010 "--bv-eq-slicer=off");
2011 if (options::produceModels())
2012 throw ModalException(
2013 "Slicer does not currently support model generation. Use "
2014 "--bv-eq-slicer=off");
2015 }
2016 else if (options::bitvectorEqualitySlicer() == bv::BITVECTOR_SLICER_OFF)
2017 {
2018 return;
2019 }
2020 else if (options::bitvectorEqualitySlicer() == bv::BITVECTOR_SLICER_AUTO)
2021 {
2022 if ((!d_logicInfo.isPure(theory::THEORY_BV) || d_logicInfo.isQuantified())
2023 || options::incrementalSolving()
2024 || options::produceModels())
2025 return;
2026
2027 bv::utils::TNodeBoolMap cache;
2028 for (unsigned i = 0; i < assertions.size(); ++i)
2029 {
2030 useSlicer = useSlicer && bv::utils::isCoreTerm(assertions[i], cache);
2031 }
2032 }
2033
2034 if (useSlicer)
2035 {
2036 bv::TheoryBV* bv_theory = (bv::TheoryBV*)d_theoryTable[THEORY_BV];
2037 bv_theory->enableCoreTheorySlicer();
2038 }
2039 }
2040
2041 void TheoryEngine::getExplanation(std::vector<NodeTheoryPair>& explanationVector, LemmaProofRecipe* proofRecipe) {
2042 Assert(explanationVector.size() > 0);
2043
2044 unsigned i = 0; // Index of the current literal we are processing
2045 unsigned j = 0; // Index of the last literal we are keeping
2046
2047 std::unique_ptr<std::set<Node>> inputAssertions = nullptr;
2048 PROOF({
2049 if (proofRecipe)
2050 {
2051 inputAssertions.reset(
2052 new std::set<Node>(proofRecipe->getStep(0)->getAssertions()));
2053 }
2054 });
2055
2056 while (i < explanationVector.size()) {
2057 // Get the current literal to explain
2058 NodeTheoryPair toExplain = explanationVector[i];
2059
2060 Debug("theory::explain") << "[i=" << i << "] TheoryEngine::explain(): processing [" << toExplain.timestamp << "] " << toExplain.node << " sent from " << toExplain.theory << endl;
2061
2062
2063 // If a true constant or a negation of a false constant we can ignore it
2064 if (toExplain.node.isConst() && toExplain.node.getConst<bool>()) {
2065 ++ i;
2066 continue;
2067 }
2068 if (toExplain.node.getKind() == kind::NOT && toExplain.node[0].isConst() && !toExplain.node[0].getConst<bool>()) {
2069 ++ i;
2070 continue;
2071 }
2072
2073 // If from the SAT solver, keep it
2074 if (toExplain.theory == THEORY_SAT_SOLVER) {
2075 Debug("theory::explain") << "\tLiteral came from THEORY_SAT_SOLVER. Kepping it." << endl;
2076 explanationVector[j++] = explanationVector[i++];
2077 continue;
2078 }
2079
2080 // If an and, expand it
2081 if (toExplain.node.getKind() == kind::AND) {
2082 Debug("theory::explain") << "TheoryEngine::explain(): expanding " << toExplain.node << " got from " << toExplain.theory << endl;
2083 for (unsigned k = 0; k < toExplain.node.getNumChildren(); ++ k) {
2084 NodeTheoryPair newExplain(toExplain.node[k], toExplain.theory, toExplain.timestamp);
2085 explanationVector.push_back(newExplain);
2086 }
2087 ++ i;
2088 continue;
2089 }
2090
2091 // See if it was sent to the theory by another theory
2092 PropagationMap::const_iterator find = d_propagationMap.find(toExplain);
2093 if (find != d_propagationMap.end()) {
2094 Debug("theory::explain")
2095 << "\tTerm was propagated by another theory (theory = "
2096 << getTheoryString((*find).second.theory) << ")" << std::endl;
2097 // There is some propagation, check if its a timely one
2098 if ((*find).second.timestamp < toExplain.timestamp) {
2099 Debug("theory::explain") << "\tRelevant timetsamp, pushing "
2100 << (*find).second.node << "to index = " << explanationVector.size() << std::endl;
2101 explanationVector.push_back((*find).second);
2102 ++i;
2103
2104 PROOF({
2105 if (toExplain.node != (*find).second.node) {
2106 Debug("pf::explain") << "TheoryEngine::getExplanation: Rewrite alert! toAssert = " << toExplain.node
2107 << ", toExplain = " << (*find).second.node << std::endl;
2108
2109 if (proofRecipe) {
2110 proofRecipe->addRewriteRule(toExplain.node, (*find).second.node);
2111 }
2112 }
2113 })
2114
2115 continue;
2116 }
2117 }
2118
2119 // It was produced by the theory, so ask for an explanation
2120 Node explanation;
2121 if (toExplain.theory == THEORY_BUILTIN) {
2122 explanation = d_sharedTerms.explain(toExplain.node);
2123 Debug("theory::explain") << "\tTerm was propagated by THEORY_BUILTIN. Explanation: " << explanation << std::endl;
2124 } else {
2125 explanation = theoryOf(toExplain.theory)->explain(toExplain.node);
2126 Debug("theory::explain") << "\tTerm was propagated by owner theory: "
2127 << theoryOf(toExplain.theory)->getId()
2128 << ". Explanation: " << explanation << std::endl;
2129 }
2130
2131 Debug("theory::explain") << "TheoryEngine::explain(): got explanation " << explanation << " got from " << toExplain.theory << endl;
2132 Assert(explanation != toExplain.node)
2133 << "wasn't sent to you, so why are you explaining it trivially";
2134 // Mark the explanation
2135 NodeTheoryPair newExplain(explanation, toExplain.theory, toExplain.timestamp);
2136 explanationVector.push_back(newExplain);
2137
2138 ++ i;
2139
2140 PROOF({
2141 if (proofRecipe && inputAssertions)
2142 {
2143 // If we're expanding the target node of the explanation (this is the
2144 // first expansion...), we don't want to add it as a separate proof
2145 // step. It is already part of the assertions.
2146 if (!ContainsKey(*inputAssertions, toExplain.node))
2147 {
2148 LemmaProofRecipe::ProofStep proofStep(toExplain.theory,
2149 toExplain.node);
2150 if (explanation.getKind() == kind::AND)
2151 {
2152 Node flat = flattenAnd(explanation);
2153 for (unsigned k = 0; k < flat.getNumChildren(); ++k)
2154 {
2155 // If a true constant or a negation of a false constant we can
2156 // ignore it
2157 if (!((flat[k].isConst() && flat[k].getConst<bool>())
2158 || (flat[k].getKind() == kind::NOT && flat[k][0].isConst()
2159 && !flat[k][0].getConst<bool>())))
2160 {
2161 proofStep.addAssertion(flat[k].negate());
2162 }
2163 }
2164 }
2165 else
2166 {
2167 if (!((explanation.isConst() && explanation.getConst<bool>())
2168 || (explanation.getKind() == kind::NOT
2169 && explanation[0].isConst()
2170 && !explanation[0].getConst<bool>())))
2171 {
2172 proofStep.addAssertion(explanation.negate());
2173 }
2174 }
2175 proofRecipe->addStep(proofStep);
2176 }
2177 }
2178 });
2179 }
2180
2181 // Keep only the relevant literals
2182 explanationVector.resize(j);
2183
2184 PROOF({
2185 if (proofRecipe) {
2186 // The remaining literals are the base of the proof
2187 for (unsigned k = 0; k < explanationVector.size(); ++k) {
2188 proofRecipe->addBaseAssertion(explanationVector[k].node.negate());
2189 }
2190 }
2191 });
2192 }
2193
2194 void TheoryEngine::setUserAttribute(const std::string& attr,
2195 Node n,
2196 const std::vector<Node>& node_values,
2197 const std::string& str_value)
2198 {
2199 Trace("te-attr") << "set user attribute " << attr << " " << n << endl;
2200 if( d_attr_handle.find( attr )!=d_attr_handle.end() ){
2201 for( size_t i=0; i<d_attr_handle[attr].size(); i++ ){
2202 d_attr_handle[attr][i]->setUserAttribute(attr, n, node_values, str_value);
2203 }
2204 } else {
2205 //unhandled exception?
2206 }
2207 }
2208
2209 void TheoryEngine::handleUserAttribute(const char* attr, Theory* t) {
2210 Trace("te-attr") << "Handle user attribute " << attr << " " << t << endl;
2211 std::string str( attr );
2212 d_attr_handle[ str ].push_back( t );
2213 }
2214
2215 void TheoryEngine::checkTheoryAssertionsWithModel(bool hardFailure) {
2216 for(TheoryId theoryId = THEORY_FIRST; theoryId < THEORY_LAST; ++theoryId) {
2217 Theory* theory = d_theoryTable[theoryId];
2218 if(theory && d_logicInfo.isTheoryEnabled(theoryId)) {
2219 for(context::CDList<Assertion>::const_iterator it = theory->facts_begin(),
2220 it_end = theory->facts_end();
2221 it != it_end;
2222 ++it) {
2223 Node assertion = (*it).assertion;
2224 Node val = getModel()->getValue(assertion);
2225 if (val != d_true)
2226 {
2227 if (hardFailure)
2228 {
2229 InternalError()
2230 << theoryId
2231 << " has an asserted fact that the model doesn't satisfy."
2232 << endl
2233 << "The fact: " << assertion << endl
2234 << "Model value: " << val << endl;
2235 }
2236 }
2237 }
2238 }
2239 }
2240 }
2241
2242 std::pair<bool, Node> TheoryEngine::entailmentCheck(theory::TheoryOfMode mode, TNode lit, const EntailmentCheckParameters* params, EntailmentCheckSideEffects* seffects) {
2243 TNode atom = (lit.getKind() == kind::NOT) ? lit[0] : lit;
2244 if( atom.getKind()==kind::AND || atom.getKind()==kind::OR || atom.getKind()==kind::IMPLIES ){
2245 //Boolean connective, recurse
2246 std::vector< Node > children;
2247 bool pol = (lit.getKind()!=kind::NOT);
2248 bool is_conjunction = pol==(lit.getKind()==kind::AND);
2249 for( unsigned i=0; i<atom.getNumChildren(); i++ ){
2250 Node ch = atom[i];
2251 if( pol==( lit.getKind()==kind::IMPLIES && i==0 ) ){
2252 ch = atom[i].negate();
2253 }
2254 std::pair<bool, Node> chres = entailmentCheck( mode, ch, params, seffects );
2255 if( chres.first ){
2256 if( !is_conjunction ){
2257 return chres;
2258 }else{
2259 children.push_back( chres.second );
2260 }
2261 }else if( !chres.first && is_conjunction ){
2262 return std::pair<bool, Node>(false, Node::null());
2263 }
2264 }
2265 if( is_conjunction ){
2266 return std::pair<bool, Node>(true, NodeManager::currentNM()->mkNode(kind::AND, children));
2267 }else{
2268 return std::pair<bool, Node>(false, Node::null());
2269 }
2270 }else if( atom.getKind()==kind::ITE || ( atom.getKind()==kind::EQUAL && atom[0].getType().isBoolean() ) ){
2271 bool pol = (lit.getKind()!=kind::NOT);
2272 for( unsigned r=0; r<2; r++ ){
2273 Node ch = atom[0];
2274 if( r==1 ){
2275 ch = ch.negate();
2276 }
2277 std::pair<bool, Node> chres = entailmentCheck( mode, ch, params, seffects );
2278 if( chres.first ){
2279 Node ch2 = atom[ atom.getKind()==kind::ITE ? r+1 : 1 ];
2280 if( pol==( atom.getKind()==kind::ITE ? true : r==1 ) ){
2281 ch2 = ch2.negate();
2282 }
2283 std::pair<bool, Node> chres2 = entailmentCheck( mode, ch2, params, seffects );
2284 if( chres2.first ){
2285 return std::pair<bool, Node>(true, NodeManager::currentNM()->mkNode(kind::AND, chres.second, chres2.second));
2286 }else{
2287 break;
2288 }
2289 }
2290 }
2291 return std::pair<bool, Node>(false, Node::null());
2292 }else{
2293 //it is a theory atom
2294 theory::TheoryId tid = theory::Theory::theoryOf(mode, atom);
2295 theory::Theory* th = theoryOf(tid);
2296
2297 Assert(th != NULL);
2298 Assert(params == NULL || tid == params->getTheoryId());
2299 Assert(seffects == NULL || tid == seffects->getTheoryId());
2300 Trace("theory-engine-entc") << "Entailment check : " << lit << std::endl;
2301
2302 std::pair<bool, Node> chres = th->entailmentCheck(lit, params, seffects);
2303 return chres;
2304 }
2305 }
2306
2307 void TheoryEngine::spendResource(unsigned amount)
2308 {
2309 d_resourceManager->spendResource(amount);
2310 }
2311
2312 void TheoryEngine::enableTheoryAlternative(const std::string& name){
2313 Debug("TheoryEngine::enableTheoryAlternative")
2314 << "TheoryEngine::enableTheoryAlternative(" << name << ")" << std::endl;
2315
2316 d_theoryAlternatives.insert(name);
2317 }
2318
2319 bool TheoryEngine::useTheoryAlternative(const std::string& name) {
2320 return d_theoryAlternatives.find(name) != d_theoryAlternatives.end();
2321 }
2322
2323
2324 TheoryEngine::Statistics::Statistics(theory::TheoryId theory):
2325 conflicts(getStatsPrefix(theory) + "::conflicts", 0),
2326 propagations(getStatsPrefix(theory) + "::propagations", 0),
2327 lemmas(getStatsPrefix(theory) + "::lemmas", 0),
2328 requirePhase(getStatsPrefix(theory) + "::requirePhase", 0),
2329 restartDemands(getStatsPrefix(theory) + "::restartDemands", 0)
2330 {
2331 smtStatisticsRegistry()->registerStat(&conflicts);
2332 smtStatisticsRegistry()->registerStat(&propagations);
2333 smtStatisticsRegistry()->registerStat(&lemmas);
2334 smtStatisticsRegistry()->registerStat(&requirePhase);
2335 smtStatisticsRegistry()->registerStat(&restartDemands);
2336 }
2337
2338 TheoryEngine::Statistics::~Statistics() {
2339 smtStatisticsRegistry()->unregisterStat(&conflicts);
2340 smtStatisticsRegistry()->unregisterStat(&propagations);
2341 smtStatisticsRegistry()->unregisterStat(&lemmas);
2342 smtStatisticsRegistry()->unregisterStat(&requirePhase);
2343 smtStatisticsRegistry()->unregisterStat(&restartDemands);
2344 }
2345
2346 }/* CVC4 namespace */