/*! \file theory_bv.cpp
** \verbatim
** Top contributors (to current version):
- ** Liana Hadarean, Andrew Reynolds, Aina Niemetz
+ ** Mathias Preiner, Andrew Reynolds, Martin Brain
** This file is part of the CVC4 project.
** Copyright (c) 2009-2020 by the authors listed in the file AUTHORS
- ** in the top-level source directory) and their institutional affiliations.
+ ** in the top-level source directory and their institutional affiliations.
** All rights reserved. See the file COPYING in the top-level source
** directory for licensing information.\endverbatim
**
#include "theory/bv/theory_bv.h"
-#include "expr/node_algorithm.h"
#include "options/bv_options.h"
#include "options/smt_options.h"
-#include "smt/smt_statistics_registry.h"
-#include "theory/bv/abstraction.h"
-#include "theory/bv/bv_eager_solver.h"
-#include "theory/bv/bv_subtheory_algebraic.h"
-#include "theory/bv/bv_subtheory_bitblast.h"
-#include "theory/bv/bv_subtheory_core.h"
-#include "theory/bv/bv_subtheory_inequality.h"
-#include "theory/bv/theory_bv_rewrite_rules_normalization.h"
-#include "theory/bv/theory_bv_rewrite_rules_simplification.h"
-#include "theory/bv/theory_bv_rewriter.h"
+#include "theory/bv/bv_solver_bitblast.h"
+#include "theory/bv/bv_solver_lazy.h"
+#include "theory/bv/bv_solver_simple.h"
#include "theory/bv/theory_bv_utils.h"
-#include "theory/theory_model.h"
-#include "theory/valuation.h"
-
-using namespace CVC4::context;
-using namespace CVC4::theory::bv::utils;
-using namespace std;
namespace CVC4 {
namespace theory {
ProofNodeManager* pnm,
std::string name)
: Theory(THEORY_BV, c, u, out, valuation, logicInfo, pnm, name),
- d_context(c),
- d_alreadyPropagatedSet(c),
- d_sharedTermsSet(c),
- d_subtheories(),
- d_subtheoryMap(),
- d_statistics(),
- d_staticLearnCache(),
- d_BVDivByZero(),
- d_BVRemByZero(),
- d_lemmasAdded(c, false),
- d_conflict(c, false),
- d_invalidateModelCache(c, true),
- d_literalsToPropagate(c),
- d_literalsToPropagateIndex(c, 0),
- d_propagatedBy(c),
- d_eagerSolver(),
- d_abstractionModule(new AbstractionModule(getStatsPrefix(THEORY_BV))),
- d_calledPreregister(false),
- d_state(c, u, valuation)
+ d_internal(nullptr),
+ d_ufDivByZero(),
+ d_ufRemByZero(),
+ d_rewriter(),
+ d_state(c, u, valuation),
+ d_im(*this, d_state, nullptr),
+ d_notify(d_im)
{
- if (options::bitblastMode() == options::BitblastMode::EAGER)
- {
- d_eagerSolver.reset(new EagerBitblastSolver(c, this));
- return;
- }
-
- if (options::bitvectorEqualitySolver())
+ switch (options::bvSolver())
{
- d_subtheories.emplace_back(new CoreSolver(c, this));
- d_subtheoryMap[SUB_CORE] = d_subtheories.back().get();
- }
-
- if (options::bitvectorInequalitySolver())
- {
- d_subtheories.emplace_back(new InequalitySolver(c, u, this));
- d_subtheoryMap[SUB_INEQUALITY] = d_subtheories.back().get();
- }
+ case options::BVSolver::BITBLAST:
+ d_internal.reset(new BVSolverBitblast(&d_state, d_im, pnm));
+ break;
- if (options::bitvectorAlgebraicSolver())
- {
- d_subtheories.emplace_back(new AlgebraicSolver(c, this));
- d_subtheoryMap[SUB_ALGEBRAIC] = d_subtheories.back().get();
- }
+ case options::BVSolver::LAZY:
+ d_internal.reset(new BVSolverLazy(*this, c, u, pnm, name));
+ break;
- BitblastSolver* bb_solver = new BitblastSolver(c, this);
- if (options::bvAbstraction())
- {
- bb_solver->setAbstraction(d_abstractionModule.get());
+ default:
+ AlwaysAssert(options::bvSolver() == options::BVSolver::SIMPLE);
+ d_internal.reset(new BVSolverSimple(&d_state, d_im, pnm));
}
- d_subtheories.emplace_back(bb_solver);
- d_subtheoryMap[SUB_BITBLAST] = bb_solver;
-
- // indicate we are using the default theory state object
d_theoryState = &d_state;
+ d_inferManager = &d_im;
}
TheoryBV::~TheoryBV() {}
bool TheoryBV::needsEqualityEngine(EeSetupInfo& esi)
{
- CoreSolver* core = (CoreSolver*)d_subtheoryMap[SUB_CORE];
- if (core)
+ bool need_ee = d_internal->needsEqualityEngine(esi);
+
+ /* Set up default notify class for equality engine. */
+ if (need_ee && esi.d_notify == nullptr)
{
- return core->needsEqualityEngine(esi);
+ esi.d_notify = &d_notify;
+ esi.d_name = "theory::bv::ee";
}
- // otherwise we don't use an equality engine
- return false;
+
+ return need_ee;
}
void TheoryBV::finishInit()
{
// these kinds are semi-evaluated in getModelValue (applications of this
// kind are treated as variables)
- d_valuation.setSemiEvaluatedKind(kind::BITVECTOR_ACKERMANNIZE_UDIV);
- d_valuation.setSemiEvaluatedKind(kind::BITVECTOR_ACKERMANNIZE_UREM);
+ getValuation().setSemiEvaluatedKind(kind::BITVECTOR_ACKERMANNIZE_UDIV);
+ getValuation().setSemiEvaluatedKind(kind::BITVECTOR_ACKERMANNIZE_UREM);
+ d_internal->finishInit();
- CoreSolver* core = (CoreSolver*)d_subtheoryMap[SUB_CORE];
- if (core)
+ eq::EqualityEngine* ee = getEqualityEngine();
+ if (ee)
{
- // must finish initialization in the core solver
- core->finishInit();
+ // The kinds we are treating as function application in congruence
+ ee->addFunctionKind(kind::BITVECTOR_CONCAT, true);
+ // ee->addFunctionKind(kind::BITVECTOR_AND);
+ // ee->addFunctionKind(kind::BITVECTOR_OR);
+ // ee->addFunctionKind(kind::BITVECTOR_XOR);
+ // ee->addFunctionKind(kind::BITVECTOR_NOT);
+ // ee->addFunctionKind(kind::BITVECTOR_NAND);
+ // ee->addFunctionKind(kind::BITVECTOR_NOR);
+ // ee->addFunctionKind(kind::BITVECTOR_XNOR);
+ // ee->addFunctionKind(kind::BITVECTOR_COMP);
+ ee->addFunctionKind(kind::BITVECTOR_MULT, true);
+ ee->addFunctionKind(kind::BITVECTOR_PLUS, true);
+ ee->addFunctionKind(kind::BITVECTOR_EXTRACT, true);
+ // ee->addFunctionKind(kind::BITVECTOR_SUB);
+ // ee->addFunctionKind(kind::BITVECTOR_NEG);
+ // ee->addFunctionKind(kind::BITVECTOR_UDIV);
+ // ee->addFunctionKind(kind::BITVECTOR_UREM);
+ // ee->addFunctionKind(kind::BITVECTOR_SDIV);
+ // ee->addFunctionKind(kind::BITVECTOR_SREM);
+ // ee->addFunctionKind(kind::BITVECTOR_SMOD);
+ // ee->addFunctionKind(kind::BITVECTOR_SHL);
+ // ee->addFunctionKind(kind::BITVECTOR_LSHR);
+ // ee->addFunctionKind(kind::BITVECTOR_ASHR);
+ // ee->addFunctionKind(kind::BITVECTOR_ULT);
+ // ee->addFunctionKind(kind::BITVECTOR_ULE);
+ // ee->addFunctionKind(kind::BITVECTOR_UGT);
+ // ee->addFunctionKind(kind::BITVECTOR_UGE);
+ // ee->addFunctionKind(kind::BITVECTOR_SLT);
+ // ee->addFunctionKind(kind::BITVECTOR_SLE);
+ // ee->addFunctionKind(kind::BITVECTOR_SGT);
+ // ee->addFunctionKind(kind::BITVECTOR_SGE);
+ ee->addFunctionKind(kind::BITVECTOR_TO_NAT);
+ ee->addFunctionKind(kind::INT_TO_BITVECTOR);
}
}
-void TheoryBV::spendResource(ResourceManager::Resource r)
+Node TheoryBV::getUFDivByZero(Kind k, unsigned width)
{
- getOutputChannel().spendResource(r);
-}
-
-TheoryBV::Statistics::Statistics():
- d_avgConflictSize("theory::bv::AvgBVConflictSize"),
- d_solveSubstitutions("theory::bv::NumSolveSubstitutions", 0),
- d_solveTimer("theory::bv::solveTimer"),
- d_numCallsToCheckFullEffort("theory::bv::NumFullCheckCalls", 0),
- d_numCallsToCheckStandardEffort("theory::bv::NumStandardCheckCalls", 0),
- d_weightComputationTimer("theory::bv::weightComputationTimer"),
- d_numMultSlice("theory::bv::NumMultSliceApplied", 0)
-{
- smtStatisticsRegistry()->registerStat(&d_avgConflictSize);
- smtStatisticsRegistry()->registerStat(&d_solveSubstitutions);
- smtStatisticsRegistry()->registerStat(&d_solveTimer);
- smtStatisticsRegistry()->registerStat(&d_numCallsToCheckFullEffort);
- smtStatisticsRegistry()->registerStat(&d_numCallsToCheckStandardEffort);
- smtStatisticsRegistry()->registerStat(&d_weightComputationTimer);
- smtStatisticsRegistry()->registerStat(&d_numMultSlice);
-}
-
-TheoryBV::Statistics::~Statistics() {
- smtStatisticsRegistry()->unregisterStat(&d_avgConflictSize);
- smtStatisticsRegistry()->unregisterStat(&d_solveSubstitutions);
- smtStatisticsRegistry()->unregisterStat(&d_solveTimer);
- smtStatisticsRegistry()->unregisterStat(&d_numCallsToCheckFullEffort);
- smtStatisticsRegistry()->unregisterStat(&d_numCallsToCheckStandardEffort);
- smtStatisticsRegistry()->unregisterStat(&d_weightComputationTimer);
- smtStatisticsRegistry()->unregisterStat(&d_numMultSlice);
-}
-
-Node TheoryBV::getBVDivByZero(Kind k, unsigned width) {
NodeManager* nm = NodeManager::currentNM();
- if (k == kind::BITVECTOR_UDIV) {
- if (d_BVDivByZero.find(width) == d_BVDivByZero.end()) {
+ if (k == kind::BITVECTOR_UDIV)
+ {
+ if (d_ufDivByZero.find(width) == d_ufDivByZero.end())
+ {
// lazily create the function symbols
- ostringstream os;
+ std::ostringstream os;
os << "BVUDivByZero_" << width;
- Node divByZero = nm->mkSkolem(os.str(),
- nm->mkFunctionType(nm->mkBitVectorType(width), nm->mkBitVectorType(width)),
- "partial bvudiv", NodeManager::SKOLEM_EXACT_NAME);
- d_BVDivByZero[width] = divByZero;
+ Node divByZero =
+ nm->mkSkolem(os.str(),
+ nm->mkFunctionType(nm->mkBitVectorType(width),
+ nm->mkBitVectorType(width)),
+ "partial bvudiv",
+ NodeManager::SKOLEM_EXACT_NAME);
+ d_ufDivByZero[width] = divByZero;
}
- return d_BVDivByZero[width];
+ return d_ufDivByZero[width];
}
- else if (k == kind::BITVECTOR_UREM) {
- if (d_BVRemByZero.find(width) == d_BVRemByZero.end()) {
- ostringstream os;
+ else if (k == kind::BITVECTOR_UREM)
+ {
+ if (d_ufRemByZero.find(width) == d_ufRemByZero.end())
+ {
+ std::ostringstream os;
os << "BVURemByZero_" << width;
- Node divByZero = nm->mkSkolem(os.str(),
- nm->mkFunctionType(nm->mkBitVectorType(width), nm->mkBitVectorType(width)),
- "partial bvurem", NodeManager::SKOLEM_EXACT_NAME);
- d_BVRemByZero[width] = divByZero;
+ Node divByZero =
+ nm->mkSkolem(os.str(),
+ nm->mkFunctionType(nm->mkBitVectorType(width),
+ nm->mkBitVectorType(width)),
+ "partial bvurem",
+ NodeManager::SKOLEM_EXACT_NAME);
+ d_ufRemByZero[width] = divByZero;
}
- return d_BVRemByZero[width];
+ return d_ufRemByZero[width];
}
Unreachable();
TrustNode TheoryBV::expandDefinition(Node node)
{
- Debug("bitvector-expandDefinition") << "TheoryBV::expandDefinition(" << node << ")" << std::endl;
+ Debug("bitvector-expandDefinition")
+ << "TheoryBV::expandDefinition(" << node << ")" << std::endl;
Node ret;
- switch (node.getKind()) {
- case kind::BITVECTOR_SDIV:
- case kind::BITVECTOR_SREM:
- case kind::BITVECTOR_SMOD:
- ret = TheoryBVRewriter::eliminateBVSDiv(node);
- break;
+ switch (node.getKind())
+ {
+ case kind::BITVECTOR_SDIV:
+ case kind::BITVECTOR_SREM:
+ case kind::BITVECTOR_SMOD:
+ ret = TheoryBVRewriter::eliminateBVSDiv(node);
+ break;
- case kind::BITVECTOR_UDIV:
- case kind::BITVECTOR_UREM: {
- NodeManager* nm = NodeManager::currentNM();
- unsigned width = node.getType().getBitVectorSize();
+ case kind::BITVECTOR_UDIV:
+ case kind::BITVECTOR_UREM:
+ {
+ NodeManager* nm = NodeManager::currentNM();
- if (options::bitvectorDivByZeroConst()) {
- Kind kind = node.getKind() == kind::BITVECTOR_UDIV ? kind::BITVECTOR_UDIV_TOTAL : kind::BITVECTOR_UREM_TOTAL;
+ Kind kind = node.getKind() == kind::BITVECTOR_UDIV
+ ? kind::BITVECTOR_UDIV_TOTAL
+ : kind::BITVECTOR_UREM_TOTAL;
ret = nm->mkNode(kind, node[0], node[1]);
break;
}
-
- TNode num = node[0], den = node[1];
- Node den_eq_0 = nm->mkNode(kind::EQUAL, den, utils::mkZero(width));
- Node divTotalNumDen = nm->mkNode(node.getKind() == kind::BITVECTOR_UDIV
- ? kind::BITVECTOR_UDIV_TOTAL
- : kind::BITVECTOR_UREM_TOTAL,
- num,
- den);
- Node divByZero = getBVDivByZero(node.getKind(), width);
- Node divByZeroNum = nm->mkNode(kind::APPLY_UF, divByZero, num);
- ret = nm->mkNode(kind::ITE, den_eq_0, divByZeroNum, divTotalNumDen);
- }
break;
- default:
- break;
+ default: break;
}
if (!ret.isNull() && node != ret)
{
return TrustNode::null();
}
-void TheoryBV::preRegisterTerm(TNode node) {
- d_calledPreregister = true;
- Debug("bitvector-preregister") << "TheoryBV::preRegister(" << node << ")" << std::endl;
+void TheoryBV::preRegisterTerm(TNode node)
+{
+ d_internal->preRegisterTerm(node);
- if (options::bitblastMode() == options::BitblastMode::EAGER)
+ eq::EqualityEngine* ee = getEqualityEngine();
+ if (ee)
{
- // the aig bit-blaster option is set heuristically
- // if bv abstraction is used
- if (!d_eagerSolver->isInitialized())
+ if (node.getKind() == kind::EQUAL)
{
- d_eagerSolver->initialize();
+ ee->addTriggerPredicate(node);
}
-
- if (node.getKind() == kind::BITVECTOR_EAGER_ATOM)
+ else
{
- Node formula = node[0];
- d_eagerSolver->assertFormula(formula);
+ ee->addTerm(node);
}
- return;
- }
-
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- d_subtheories[i]->preRegister(node);
}
-
- // AJR : equality solver currently registers all terms to ExtTheory, if we
- // want a lazy reduction without the bv equality solver, need to call this
- // d_extTheory->registerTermRec( node );
}
-void TheoryBV::sendConflict() {
- Assert(d_conflict);
- if (d_conflictNode.isNull()) {
- return;
- } else {
- Debug("bitvector") << indent() << "TheoryBV::check(): conflict " << d_conflictNode << std::endl;
- d_out->conflict(d_conflictNode);
- d_statistics.d_avgConflictSize.addEntry(d_conflictNode.getNumChildren());
- d_conflictNode = Node::null();
- }
-}
+bool TheoryBV::preCheck(Effort e) { return d_internal->preCheck(e); }
+
+void TheoryBV::postCheck(Effort e) { d_internal->postCheck(e); }
-void TheoryBV::checkForLemma(TNode fact)
+bool TheoryBV::preNotifyFact(
+ TNode atom, bool pol, TNode fact, bool isPrereg, bool isInternal)
{
- if (fact.getKind() == kind::EQUAL)
- {
- NodeManager* nm = NodeManager::currentNM();
- if (fact[0].getKind() == kind::BITVECTOR_UREM_TOTAL)
- {
- TNode urem = fact[0];
- TNode result = fact[1];
- TNode divisor = urem[1];
- Node result_ult_div = nm->mkNode(kind::BITVECTOR_ULT, result, divisor);
- Node divisor_eq_0 =
- nm->mkNode(kind::EQUAL, divisor, mkZero(getSize(divisor)));
- Node split = nm->mkNode(
- kind::OR, divisor_eq_0, nm->mkNode(kind::NOT, fact), result_ult_div);
- lemma(split);
- }
- if (fact[1].getKind() == kind::BITVECTOR_UREM_TOTAL)
- {
- TNode urem = fact[1];
- TNode result = fact[0];
- TNode divisor = urem[1];
- Node result_ult_div = nm->mkNode(kind::BITVECTOR_ULT, result, divisor);
- Node divisor_eq_0 =
- nm->mkNode(kind::EQUAL, divisor, mkZero(getSize(divisor)));
- Node split = nm->mkNode(
- kind::OR, divisor_eq_0, nm->mkNode(kind::NOT, fact), result_ult_div);
- lemma(split);
- }
- }
+ return d_internal->preNotifyFact(atom, pol, fact, isPrereg, isInternal);
}
-void TheoryBV::check(Effort e)
+void TheoryBV::notifyFact(TNode atom, bool pol, TNode fact, bool isInternal)
{
- if (done() && e<Theory::EFFORT_FULL) {
- return;
- }
-
- //last call : do reductions on extended bitvector functions
- if (e == Theory::EFFORT_LAST_CALL) {
- CoreSolver* core = (CoreSolver*)d_subtheoryMap[SUB_CORE];
- if (core)
- {
- // check extended functions at last call effort
- core->checkExtf(e);
- }
- return;
- }
-
- TimerStat::CodeTimer checkTimer(d_checkTime);
- Debug("bitvector") << "TheoryBV::check(" << e << ")" << std::endl;
- TimerStat::CodeTimer codeTimer(d_statistics.d_solveTimer);
- // we may be getting new assertions so the model cache may not be sound
- d_invalidateModelCache.set(true);
- // if we are using the eager solver
- if (options::bitblastMode() == options::BitblastMode::EAGER)
- {
- // this can only happen on an empty benchmark
- if (!d_eagerSolver->isInitialized()) {
- d_eagerSolver->initialize();
- }
- if (!Theory::fullEffort(e))
- return;
-
- std::vector<TNode> assertions;
- while (!done()) {
- TNode fact = get().d_assertion;
- Assert(fact.getKind() == kind::BITVECTOR_EAGER_ATOM);
- assertions.push_back(fact);
- d_eagerSolver->assertFormula(fact[0]);
- }
-
- bool ok = d_eagerSolver->checkSat();
- if (!ok) {
- if (assertions.size() == 1) {
- d_out->conflict(assertions[0]);
- return;
- }
- Node conflict = utils::mkAnd(assertions);
- d_out->conflict(conflict);
- return;
- }
- return;
- }
-
- if (Theory::fullEffort(e)) {
- ++(d_statistics.d_numCallsToCheckFullEffort);
- } else {
- ++(d_statistics.d_numCallsToCheckStandardEffort);
- }
- // if we are already in conflict just return the conflict
- if (inConflict()) {
- sendConflict();
- return;
- }
-
- while (!done()) {
- TNode fact = get().d_assertion;
-
- checkForLemma(fact);
-
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- d_subtheories[i]->assertFact(fact);
- }
- }
-
- bool ok = true;
- bool complete = false;
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- Assert(!inConflict());
- ok = d_subtheories[i]->check(e);
- complete = d_subtheories[i]->isComplete();
-
- if (!ok) {
- // if we are in a conflict no need to check with other theories
- Assert(inConflict());
- sendConflict();
- return;
- }
- if (complete) {
- // if the last subtheory was complete we stop
- break;
- }
- }
-
- //check extended functions
- if (Theory::fullEffort(e)) {
- CoreSolver* core = (CoreSolver*)d_subtheoryMap[SUB_CORE];
- if (core)
- {
- // check extended functions at full effort
- core->checkExtf(e);
- }
- }
+ d_internal->notifyFact(atom, pol, fact, isInternal);
}
bool TheoryBV::needsCheckLastEffort()
{
- CoreSolver* core = (CoreSolver*)d_subtheoryMap[SUB_CORE];
- if (core)
- {
- return core->needsCheckLastEffort();
- }
- return false;
-}
-bool TheoryBV::collectModelInfo(TheoryModel* m)
-{
- Assert(!inConflict());
- if (options::bitblastMode() == options::BitblastMode::EAGER)
- {
- if (!d_eagerSolver->collectModelInfo(m, true))
- {
- return false;
- }
- }
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- if (d_subtheories[i]->isComplete()) {
- return d_subtheories[i]->collectModelInfo(m, true);
- }
- }
- return true;
+ return d_internal->needsCheckLastEffort();
}
-Node TheoryBV::getModelValue(TNode var) {
- Assert(!inConflict());
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- if (d_subtheories[i]->isComplete()) {
- return d_subtheories[i]->getModelValue(var);
- }
- }
- Unreachable();
+bool TheoryBV::collectModelValues(TheoryModel* m, const std::set<Node>& termSet)
+{
+ return d_internal->collectModelValues(m, termSet);
}
-void TheoryBV::propagate(Effort e) {
- Debug("bitvector") << indent() << "TheoryBV::propagate()" << std::endl;
- if (options::bitblastMode() == options::BitblastMode::EAGER)
- {
- return;
- }
-
- if (inConflict()) {
- return;
- }
-
- // go through stored propagations
- bool ok = true;
- for (; d_literalsToPropagateIndex < d_literalsToPropagate.size() && ok; d_literalsToPropagateIndex = d_literalsToPropagateIndex + 1) {
- TNode literal = d_literalsToPropagate[d_literalsToPropagateIndex];
- // temporary fix for incremental bit-blasting
- if (d_valuation.isSatLiteral(literal)) {
- Debug("bitvector::propagate") << "TheoryBV:: propagating " << literal <<"\n";
- ok = d_out->propagate(literal);
- }
- }
+void TheoryBV::propagate(Effort e) { return d_internal->propagate(e); }
- if (!ok) {
- Debug("bitvector::propagate") << indent() << "TheoryBV::propagate(): conflict from theory engine" << std::endl;
- setConflict();
- }
-}
-
-Theory::PPAssertStatus TheoryBV::ppAssert(TNode in,
- SubstitutionMap& outSubstitutions)
+Theory::PPAssertStatus TheoryBV::ppAssert(
+ TrustNode tin, TrustSubstitutionMap& outSubstitutions)
{
- switch (in.getKind())
- {
- case kind::EQUAL:
- {
- if (in[0].isVar() && isLegalElimination(in[0], in[1]))
- {
- ++(d_statistics.d_solveSubstitutions);
- outSubstitutions.addSubstitution(in[0], in[1]);
- return PP_ASSERT_STATUS_SOLVED;
- }
- if (in[1].isVar() && isLegalElimination(in[1], in[0]))
- {
- ++(d_statistics.d_solveSubstitutions);
- outSubstitutions.addSubstitution(in[1], in[0]);
- return PP_ASSERT_STATUS_SOLVED;
- }
- Node node = Rewriter::rewrite(in);
- if ((node[0].getKind() == kind::BITVECTOR_EXTRACT && node[1].isConst())
- || (node[1].getKind() == kind::BITVECTOR_EXTRACT
- && node[0].isConst()))
- {
- Node extract = node[0].isConst() ? node[1] : node[0];
- if (extract[0].isVar())
- {
- Node c = node[0].isConst() ? node[0] : node[1];
-
- unsigned high = utils::getExtractHigh(extract);
- unsigned low = utils::getExtractLow(extract);
- unsigned var_bitwidth = utils::getSize(extract[0]);
- std::vector<Node> children;
-
- if (low == 0)
- {
- Assert(high != var_bitwidth - 1);
- unsigned skolem_size = var_bitwidth - high - 1;
- Node skolem = utils::mkVar(skolem_size);
- children.push_back(skolem);
- children.push_back(c);
- }
- else if (high == var_bitwidth - 1)
- {
- unsigned skolem_size = low;
- Node skolem = utils::mkVar(skolem_size);
- children.push_back(c);
- children.push_back(skolem);
- }
- else
- {
- unsigned skolem1_size = low;
- unsigned skolem2_size = var_bitwidth - high - 1;
- Node skolem1 = utils::mkVar(skolem1_size);
- Node skolem2 = utils::mkVar(skolem2_size);
- children.push_back(skolem2);
- children.push_back(c);
- children.push_back(skolem1);
- }
- Node concat = utils::mkConcat(children);
- Assert(utils::getSize(concat) == utils::getSize(extract[0]));
- if (isLegalElimination(extract[0], concat))
- {
- outSubstitutions.addSubstitution(extract[0], concat);
- return PP_ASSERT_STATUS_SOLVED;
- }
- }
- }
- }
- break;
- case kind::BITVECTOR_ULT:
- case kind::BITVECTOR_SLT:
- case kind::BITVECTOR_ULE:
- case kind::BITVECTOR_SLE:
-
- default:
- // TODO other predicates
- break;
- }
- return PP_ASSERT_STATUS_UNSOLVED;
+ return d_internal->ppAssert(tin, outSubstitutions);
}
TrustNode TheoryBV::ppRewrite(TNode t)
{
- Debug("bv-pp-rewrite") << "TheoryBV::ppRewrite " << t << "\n";
- Node res = t;
- if (options::bitwiseEq() && RewriteRule<BitwiseEq>::applies(t)) {
- Node result = RewriteRule<BitwiseEq>::run<false>(t);
- res = Rewriter::rewrite(result);
- } else if (RewriteRule<UltPlusOne>::applies(t)) {
- Node result = RewriteRule<UltPlusOne>::run<false>(t);
- res = Rewriter::rewrite(result);
- }
- else if (res.getKind() == kind::EQUAL
- && ((res[0].getKind() == kind::BITVECTOR_PLUS
- && RewriteRule<ConcatToMult>::applies(res[1]))
- || (res[1].getKind() == kind::BITVECTOR_PLUS
- && RewriteRule<ConcatToMult>::applies(res[0]))))
- {
- Node mult = RewriteRule<ConcatToMult>::applies(res[0])?
- RewriteRule<ConcatToMult>::run<false>(res[0]) :
- RewriteRule<ConcatToMult>::run<true>(res[1]);
- Node factor = mult[0];
- Node sum = RewriteRule<ConcatToMult>::applies(res[0])? res[1] : res[0];
- Node new_eq = NodeManager::currentNM()->mkNode(kind::EQUAL, sum, mult);
- Node rewr_eq = RewriteRule<SolveEq>::run<true>(new_eq);
- if (rewr_eq[0].isVar() || rewr_eq[1].isVar()){
- res = Rewriter::rewrite(rewr_eq);
- } else {
- res = t;
- }
- }
- else if (RewriteRule<SignExtendEqConst>::applies(t))
- {
- res = RewriteRule<SignExtendEqConst>::run<false>(t);
- }
- else if (RewriteRule<ZeroExtendEqConst>::applies(t))
- {
- res = RewriteRule<ZeroExtendEqConst>::run<false>(t);
- }
- else if (RewriteRule<NormalizeEqPlusNeg>::applies(t))
+ // first, see if we need to expand definitions
+ TrustNode texp = expandDefinition(t);
+ if (!texp.isNull())
{
- res = RewriteRule<NormalizeEqPlusNeg>::run<false>(t);
+ return texp;
}
-
- // if(t.getKind() == kind::EQUAL &&
- // ((t[0].getKind() == kind::BITVECTOR_MULT && t[1].getKind() ==
- // kind::BITVECTOR_PLUS) ||
- // (t[1].getKind() == kind::BITVECTOR_MULT && t[0].getKind() ==
- // kind::BITVECTOR_PLUS))) {
- // // if we have an equality between a multiplication and addition
- // // try to express multiplication in terms of addition
- // Node mult = t[0].getKind() == kind::BITVECTOR_MULT? t[0] : t[1];
- // Node add = t[0].getKind() == kind::BITVECTOR_PLUS? t[0] : t[1];
- // if (RewriteRule<MultSlice>::applies(mult)) {
- // Node new_mult = RewriteRule<MultSlice>::run<false>(mult);
- // Node new_eq =
- // Rewriter::rewrite(NodeManager::currentNM()->mkNode(kind::EQUAL,
- // new_mult, add));
-
- // // the simplification can cause the formula to blow up
- // // only apply if formula reduced
- // if (d_subtheoryMap.find(SUB_BITBLAST) != d_subtheoryMap.end()) {
- // BitblastSolver* bv = (BitblastSolver*)d_subtheoryMap[SUB_BITBLAST];
- // uint64_t old_size = bv->computeAtomWeight(t);
- // Assert (old_size);
- // uint64_t new_size = bv->computeAtomWeight(new_eq);
- // double ratio = ((double)new_size)/old_size;
- // if (ratio <= 0.4) {
- // ++(d_statistics.d_numMultSlice);
- // return new_eq;
- // }
- // }
-
- // if (new_eq.getKind() == kind::CONST_BOOLEAN) {
- // ++(d_statistics.d_numMultSlice);
- // return new_eq;
- // }
- // }
- // }
-
- if (options::bvAbstraction() && t.getType().isBoolean()) {
- d_abstractionModule->addInputAtom(res);
- }
- Debug("bv-pp-rewrite") << "to " << res << "\n";
- if (res != t)
- {
- return TrustNode::mkTrustRewrite(t, res, nullptr);
- }
- return TrustNode::null();
+ return d_internal->ppRewrite(t);
}
-void TheoryBV::presolve() {
- Debug("bitvector") << "TheoryBV::presolve" << endl;
-}
-
-static int prop_count = 0;
+void TheoryBV::presolve() { d_internal->presolve(); }
-bool TheoryBV::storePropagation(TNode literal, SubTheory subtheory)
+EqualityStatus TheoryBV::getEqualityStatus(TNode a, TNode b)
{
- Debug("bitvector::propagate") << indent() << getSatContext()->getLevel() << " " << "TheoryBV::storePropagation(" << literal << ", " << subtheory << ")" << std::endl;
- prop_count++;
-
- // If already in conflict, no more propagation
- if (d_conflict) {
- Debug("bitvector::propagate") << indent() << "TheoryBV::storePropagation(" << literal << ", " << subtheory << "): already in conflict" << std::endl;
- return false;
- }
-
- // If propagated already, just skip
- PropagatedMap::const_iterator find = d_propagatedBy.find(literal);
- if (find != d_propagatedBy.end()) {
- return true;
- } else {
- bool polarity = literal.getKind() != kind::NOT;
- Node negatedLiteral = polarity ? literal.notNode() : (Node) literal[0];
- find = d_propagatedBy.find(negatedLiteral);
- if (find != d_propagatedBy.end() && (*find).second != subtheory) {
- // Safe to ignore this one, subtheory should produce a conflict
- return true;
- }
-
- d_propagatedBy[literal] = subtheory;
- }
-
- // Propagate differs depending on the subtheory
- // * bitblaster needs to be left alone until it's done, otherwise it doesn't
- // know how to explain
- // * equality engine can propagate eagerly
- // TODO(2348): Determine if ok should be set by propagate. If not, remove ok.
- constexpr bool ok = true;
- if (subtheory == SUB_CORE) {
- d_out->propagate(literal);
- if (!ok) {
- setConflict();
- }
- } else {
- d_literalsToPropagate.push_back(literal);
- }
- return ok;
-
-}/* TheoryBV::propagate(TNode) */
-
-
-void TheoryBV::explain(TNode literal, std::vector<TNode>& assumptions) {
- Assert(wasPropagatedBySubtheory(literal));
- SubTheory sub = getPropagatingSubtheory(literal);
- d_subtheoryMap[sub]->explain(literal, assumptions);
+ return d_internal->getEqualityStatus(a, b);
}
-TrustNode TheoryBV::explain(TNode node)
-{
- Debug("bitvector::explain") << "TheoryBV::explain(" << node << ")" << std::endl;
- std::vector<TNode> assumptions;
-
- // Ask for the explanation
- explain(node, assumptions);
- // this means that it is something true at level 0
- Node explanation;
- if (assumptions.size() == 0) {
- explanation = utils::mkTrue();
- }
- else
- {
- // return the explanation
- explanation = utils::mkAnd(assumptions);
- }
- Debug("bitvector::explain") << "TheoryBV::explain(" << node << ") => " << explanation << std::endl;
- Debug("bitvector::explain") << "TheoryBV::explain done. \n";
- return TrustNode::mkTrustPropExp(node, explanation, nullptr);
-}
+TrustNode TheoryBV::explain(TNode node) { return d_internal->explain(node); }
void TheoryBV::notifySharedTerm(TNode t)
{
- Debug("bitvector::sharing")
- << indent() << "TheoryBV::notifySharedTerm(" << t << ")" << std::endl;
- d_sharedTermsSet.insert(t);
- if (options::bitvectorEqualitySolver()) {
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- d_subtheories[i]->addSharedTerm(t);
- }
- }
+ d_internal->notifySharedTerm(t);
}
-
-EqualityStatus TheoryBV::getEqualityStatus(TNode a, TNode b)
+void TheoryBV::ppStaticLearn(TNode in, NodeBuilder<>& learned)
{
- if (options::bitblastMode() == options::BitblastMode::EAGER)
- return EQUALITY_UNKNOWN;
- Assert(options::bitblastMode() == options::BitblastMode::LAZY);
- for (unsigned i = 0; i < d_subtheories.size(); ++i) {
- EqualityStatus status = d_subtheories[i]->getEqualityStatus(a, b);
- if (status != EQUALITY_UNKNOWN) {
- return status;
- }
- }
- return EQUALITY_UNKNOWN; ;
-}
-
-void TheoryBV::ppStaticLearn(TNode in, NodeBuilder<>& learned) {
- if(d_staticLearnCache.find(in) != d_staticLearnCache.end()){
- return;
- }
- d_staticLearnCache.insert(in);
-
- if (in.getKind() == kind::EQUAL) {
- if((in[0].getKind() == kind::BITVECTOR_PLUS && in[1].getKind() == kind::BITVECTOR_SHL) ||
- (in[1].getKind() == kind::BITVECTOR_PLUS && in[0].getKind() == kind::BITVECTOR_SHL)) {
- TNode p = in[0].getKind() == kind::BITVECTOR_PLUS ? in[0] : in[1];
- TNode s = in[0].getKind() == kind::BITVECTOR_PLUS ? in[1] : in[0];
-
- if(p.getNumChildren() == 2
- && p[0].getKind() == kind::BITVECTOR_SHL
- && p[1].getKind() == kind::BITVECTOR_SHL ){
- unsigned size = utils::getSize(s);
- Node one = utils::mkConst(size, 1u);
- if(s[0] == one && p[0][0] == one && p[1][0] == one){
- Node zero = utils::mkConst(size, 0u);
- TNode b = p[0];
- TNode c = p[1];
- // (s : 1 << S) = (b : 1 << B) + (c : 1 << C)
- Node b_eq_0 = b.eqNode(zero);
- Node c_eq_0 = c.eqNode(zero);
- Node b_eq_c = b.eqNode(c);
-
- Node dis = NodeManager::currentNM()->mkNode(
- kind::OR, b_eq_0, c_eq_0, b_eq_c);
- Node imp = in.impNode(dis);
- learned << imp;
- }
- }
- }
- }else if(in.getKind() == kind::AND){
- for(size_t i = 0, N = in.getNumChildren(); i < N; ++i){
- ppStaticLearn(in[i], learned);
- }
- }
-}
-
-bool TheoryBV::applyAbstraction(const std::vector<Node>& assertions, std::vector<Node>& new_assertions) {
- bool changed = d_abstractionModule->applyAbstraction(assertions, new_assertions);
- if (changed && options::bitblastMode() == options::BitblastMode::EAGER
- && options::bitvectorAig())
- {
- // disable AIG mode
- AlwaysAssert(!d_eagerSolver->isInitialized());
- d_eagerSolver->turnOffAig();
- d_eagerSolver->initialize();
- }
- return changed;
+ d_internal->ppStaticLearn(in, learned);
}
-void TheoryBV::setConflict(Node conflict)
+bool TheoryBV::applyAbstraction(const std::vector<Node>& assertions,
+ std::vector<Node>& new_assertions)
{
- if (options::bvAbstraction())
- {
- NodeManager* const nm = NodeManager::currentNM();
- Node new_conflict = d_abstractionModule->simplifyConflict(conflict);
-
- std::vector<Node> lemmas;
- lemmas.push_back(new_conflict);
- d_abstractionModule->generalizeConflict(new_conflict, lemmas);
- for (unsigned i = 0; i < lemmas.size(); ++i)
- {
- lemma(nm->mkNode(kind::NOT, lemmas[i]));
- }
- }
- d_conflict = true;
- d_conflictNode = conflict;
+ return d_internal->applyAbstraction(assertions, new_assertions);
}
-} /* namespace CVC4::theory::bv */
-} /* namespace CVC4::theory */
-} /* namespace CVC4 */
+} // namespace bv
+} // namespace theory
+} // namespace CVC4