CVC3::SearchSat Class Reference
[Search Engine]

Search engine that connects to a generic SAT reasoning module. More...

#include <search_sat.h>

Inheritance diagram for CVC3::SearchSat:

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List of all members.

Classes

Public Member Functions

Private Member Functions

Private Attributes

Friends


Detailed Description

Search engine that connects to a generic SAT reasoning module.

Definition at line 40 of file search_sat.h.


Constructor & Destructor Documentation

SearchSat::SearchSat ( TheoryCore core,
const std::string &  name 
)

SearchSat::~SearchSat (  )  [virtual]

Destructor.

Definition at line 990 of file search_sat.cpp.

References d_cnfCallback, d_cnfManager, d_coreSatAPI, d_decider, d_dpllt, and d_theoryAPI.


Member Function Documentation

void SearchSat::restorePre (  )  [private]

void SearchSat::restore ( void   )  [private]

Get rid of entries in prioritySet and pendingLemmas added since last push.

Definition at line 129 of file search_sat.cpp.

References d_pendingLemmas, d_pendingLemmasSize, d_pendingScopes, d_prioritySet, d_prioritySetEntries, d_prioritySetEntriesSize, d_vars, d_varsUndoList, d_varsUndoListSize, and SAT::Var::UNKNOWN.

Referenced by CVC3::SearchSat::SearchSat::Restorer::notify().

bool SearchSat::recordNewRootLit ( SAT::Lit  lit,
int  priority = 0,
bool  atBottomScope = false 
) [private]

void SearchSat::addLemma ( const Theorem thm,
int  priority = 0,
bool  atBotomScope = false 
) [private]

int CVC3::SearchSat::getBottomScope (  )  [inline, private]

Core theory callback which asks for the bottom scope for current query.

Definition at line 184 of file search_sat.h.

References d_bottomScope.

void SearchSat::addSplitter ( const Expr e,
int  priority 
) [private]

Core theory callback which suggests a splitter.

Definition at line 186 of file search_sat.cpp.

References addLemma(), CVC3::SearchEngine::d_commonRules, DebugAssert, CVC3::CommonProofRules::excludedMiddle(), and CVC3::Expr::isEq().

Referenced by CVC3::SearchSatCoreSatAPI::addSplitter().

void SearchSat::assertLit ( SAT::Lit  l  )  [private]

SAT::DPLLT::ConsistentResult SearchSat::checkConsistent ( SAT::CNF_Formula cnf,
bool  fullEffort 
) [private]

Lit SearchSat::getImplication (  )  [private]

void SearchSat::getExplanation ( SAT::Lit  l,
SAT::CNF_Formula cnf 
) [private]

bool SearchSat::getNewClauses ( SAT::CNF_Formula cnf  )  [private]

Lit SearchSat::makeDecision (  )  [private]

DPLLT callback to decide which literal to split on next.

Definition at line 346 of file search_sat.cpp.

References d_inCheckSat, d_prioritySet, d_prioritySetStart, DebugAssert, findSplitterRec(), and getValue().

Referenced by CVC3::SearchSatDecider::makeDecision().

bool SearchSat::findSplitterRec ( SAT::Lit  lit,
SAT::Var::Val  value,
SAT::Lit litDecision 
) [private]

Recursively traverse DAG looking for a splitter.

Returns true if a splitter is found, false otherwise. The splitter is returned in lit (lit should be set to true). Nodes whose current value is fully justified are marked by calling setFlag to avoid searching them in the future.

Definition at line 364 of file search_sat.cpp.

References CVC3::AND, checkJustified(), SAT::CNF_Manager::concreteVar(), d_cnfManager, DebugAssert, std::endl(), CVC3::FALSE_VAL, FatalAssert, SAT::CNF_Manager::getFanin(), CVC3::Expr::getKind(), getValue(), SAT::Lit::getVar(), CVC3::IFF, CVC3::IMPLIES, CVC3::Expr::isAbsAtomicFormula(), SAT::Lit::isFalse(), SAT::Lit::isInverted(), SAT::Lit::isTrue(), SAT::Lit::isVar(), CVC3::ITE, SAT::CNF_Manager::numFanins(), CVC3::OR, setJustified(), CVC3::TRUE_VAL, CVC3::UNKNOWN, and CVC3::XOR.

Referenced by makeDecision().

SAT::Var::Val CVC3::SearchSat::getValue ( SAT::Lit  c  )  [inline, private]

SAT::Var::Val CVC3::SearchSat::getValue ( SAT::Var  v  )  [inline, private]

Definition at line 223 of file search_sat.h.

References d_vars, DebugAssert, and SAT::Var::isVar().

void CVC3::SearchSat::setValue ( SAT::Var  v,
SAT::Var::Val  val 
) [inline, private]

Set the value of a variable.

Definition at line 229 of file search_sat.h.

References d_vars, d_varsUndoList, d_varsUndoListSize, DebugAssert, SAT::Var::isNull(), and SAT::Var::UNKNOWN.

Referenced by assertLit().

bool CVC3::SearchSat::checkJustified ( SAT::Var  v  )  [inline, private]

Check whether this variable's value is justified.

Definition at line 241 of file search_sat.h.

References SAT::CNF_Manager::concreteLit(), d_cnfManager, and CVC3::Expr::isJustified().

Referenced by findSplitterRec().

void CVC3::SearchSat::setJustified ( SAT::Var  v  )  [inline, private]

Mark this variable as justified.

Definition at line 245 of file search_sat.h.

References SAT::CNF_Manager::concreteLit(), d_cnfManager, and CVC3::Expr::setJustified().

Referenced by findSplitterRec().

QueryResult SearchSat::check ( const Expr e,
Theorem result,
bool  isRestart = false 
) [private]

Main checking procedure shared by checkValid and restart.

Definition at line 638 of file search_sat.cpp.

References CVC3::CommonProofRules::assumpRule(), SAT::DPLLT::checkSat(), SAT::CNF_Manager::concreteLit(), SAT::DPLLT::continueCheck(), d_bottomScope, d_cnfManager, CVC3::SearchEngine::d_commonRules, CVC3::SearchEngine::d_core, d_dpllt, d_dplltReady, d_inCheckSat, d_lastCheck, d_lastValid, d_lemmas, d_lemmasNext, d_prioritySetBottomEntriesSize, d_prioritySetBottomEntriesSizeStack, CVC3::SearchEngine::d_rules, DebugAssert, std::endl(), CVC3::Theory::findExpr(), CVC3::FORALL, CVC3::CDO< T >::get(), CVC3::TheoryCore::getCM(), SAT::DPLLT::getCurAssignments(), SAT::DPLLT::getCurClauses(), getNewClauses(), CVC3::TheoryCore::getPredicates(), SAT::DPLLT::getSatProof(), CVC3::TheoryCore::getTerms(), CVC3::TheoryCore::getTM(), CVC3::Expr::getType(), SAT::Lit::getVar(), CVC3::TheoryCore::incomplete(), CVC3::TheoryCore::inconsistent(), CVC3::TheoryCore::inconsistentThm(), CVC3::INVALID, CVC3::Type::isBool(), CVC3::Expr::isEq(), CVC3::Expr::isExists(), CVC3::Expr::isFalse(), CVC3::Expr::isForall(), CVC3::Expr::isNot(), CVC3::Expr::isNull(), SAT::Lit::isPositive(), CVC3::Expr::isTrue(), newUserAssumptionInt(), SAT::CD_CNF_Formula::numClauses(), pop(), CVC3::SearchEngineRules::proofByContradiction(), push(), CVC3::SATISFIABLE, CVC3::SearchEngineRules::satProof(), CVC3::ContextManager::scopeLevel(), SAT::CNF_Manager::setBottomScope(), CVC3::Theory::simplifyExpr(), CVC3::CDList< T >::size(), CVC3::Theory::theoryOf(), CVC3::Type::toString(), CVC3::Expr::toString(), CVC3::TRACE, CVC3::CommonProofRules::trueTheorem(), CVC3::UNKNOWN, CVC3::UNSATISFIABLE, CVC3::VALID, and CVC3::TheoremManager::withProof().

Referenced by CVC3::SearchSatCoreSatAPI::check(), checkValid(), and restart().

void SearchSat::newUserAssumptionIntHelper ( const Theorem thm,
SAT::CNF_Formula_Impl cnf,
bool  atBottomScope 
) [private]

Theorem SearchSat::newUserAssumptionInt ( const Expr e,
SAT::CNF_Formula_Impl cnf,
bool  atBottomScope 
) [private]

virtual const std::string& CVC3::SearchSat::getName (  )  [inline, virtual]

Name of this search engine.

Implements CVC3::SearchEngine.

Definition at line 268 of file search_sat.h.

References d_name.

void SearchSat::registerAtom ( const Expr e  )  [virtual]

Register an atomic formula of interest.

Registered atoms are tracked by the decision procedures. If one of them is deduced to be true or false, it is added to a list of implied literals. Implied literals can be retrieved with the getImpliedLiteral function

Implements CVC3::SearchEngine.

Definition at line 1001 of file search_sat.cpp.

References CVC3::SearchEngine::d_core, CVC3::Expr::isRegisteredAtom(), CVC3::TheoryCore::registerAtom(), and CVC3::Expr::setUserRegisteredAtom().

Theorem SearchSat::getImpliedLiteral (  )  [virtual]

Return next literal implied by last assertion. Null Expr if none.

Returned literals are either registered atomic formulas or their negation

Implements CVC3::SearchEngine.

Definition at line 1009 of file search_sat.cpp.

References CVC3::SearchEngine::d_core, d_nextImpliedLiteral, CVC3::Theorem::getExpr(), CVC3::TheoryCore::getImpliedLiteralByIndex(), CVC3::Expr::isUserRegisteredAtom(), and CVC3::Expr::unnegate().

virtual void CVC3::SearchSat::push (  )  [inline, virtual]

Push a checkpoint.

Implements CVC3::SearchEngine.

Definition at line 271 of file search_sat.h.

References d_dpllt, and SAT::DPLLT::push().

Referenced by check(), and CVC3::SearchSatCoreSatAPI::check().

virtual void CVC3::SearchSat::pop (  )  [inline, virtual]

Restore last checkpoint.

Implements CVC3::SearchEngine.

Definition at line 272 of file search_sat.h.

References d_dpllt, and SAT::DPLLT::pop().

Referenced by check(), CVC3::SearchSatCoreSatAPI::check(), and returnFromCheck().

virtual QueryResult CVC3::SearchSat::checkValid ( const Expr e,
Theorem result 
) [inline, virtual]

Checks the validity of a formula in the current context.

If the query is valid, it returns VALID, the result parameter contains the corresponding theorem, and the scope and context are the same as when called. If it returns INVALID, the context will be one which falsifies the query. If it returns UNKNOWN, the context will falsify the query, but the context may be inconsistent. Finally, if it returns ABORT, the context will be one which satisfies as much as possible.

Parameters:
e the formula to check.
result the resulting theorem, if the formula is valid.

Implements CVC3::SearchEngine.

Definition at line 273 of file search_sat.h.

References check().

virtual QueryResult CVC3::SearchSat::restart ( const Expr e,
Theorem result 
) [inline, virtual]

Reruns last check with e as an additional assumption.

This method should only be called after a query which is invalid.

Parameters:
e the additional assumption
result the resulting theorem, if the query is valid.

Implements CVC3::SearchEngine.

Definition at line 275 of file search_sat.h.

References check().

void SearchSat::returnFromCheck (  )  [virtual]

Returns to context immediately before last call to checkValid.

This method should only be called after a query which returns something other than VALID.

Implements CVC3::SearchEngine.

Definition at line 1021 of file search_sat.cpp.

References d_bottomScope, and pop().

virtual Theorem CVC3::SearchSat::lastThm (  )  [inline, virtual]

Returns the result of the most recent valid theorem.

Returns Null Theorem if last call was not valid

Implements CVC3::SearchEngine.

Definition at line 278 of file search_sat.h.

References d_lastValid.

Theorem SearchSat::newUserAssumption ( const Expr e  )  [virtual]

Generate and add an assumption to the set of assumptions in the current context.

By default, the assumption is added at the current scope. The default can be overridden by specifying the scope parameter.

Implements CVC3::SearchEngine.

Definition at line 1101 of file search_sat.cpp.

References SAT::DPLLT::addAssertion(), d_dpllt, and newUserAssumptionInt().

Referenced by CVC3::SearchSatCoreSatAPI::addAssumption().

void SearchSat::getUserAssumptions ( std::vector< Expr > &  assumptions  )  [virtual]

Get all user assumptions made in this and all previous contexts.

User assumptions are created either by calls to newUserAssumption or a call to checkValid. In the latter case, the negated query is added as an assumption.

Parameters:
assumptions should be empty on entry.

Implements CVC3::SearchEngine.

Definition at line 1110 of file search_sat.cpp.

References CVC3::CDList< T >::begin(), d_userAssumptions, and CVC3::CDList< T >::end().

void SearchSat::getInternalAssumptions ( std::vector< Expr > &  assumptions  )  [virtual]

Get assumptions made internally in this and all previous contexts.

Internal assumptions are literals assumed by the sat solver.

Parameters:
assumptions should be empty on entry.

Implements CVC3::SearchEngine.

Definition at line 1118 of file search_sat.cpp.

References CVC3::CDList< T >::begin(), d_intAssumptions, and CVC3::CDList< T >::end().

Referenced by getCounterExample().

void SearchSat::getAssumptions ( std::vector< Expr > &  assumptions  )  [virtual]

Get all assumptions made in this and all previous contexts.

Parameters:
assumptions should be an empty vector which will be filled \ with the assumptions

Implements CVC3::SearchEngine.

Definition at line 1127 of file search_sat.cpp.

References CVC3::CDList< T >::begin(), d_intAssumptions, d_userAssumptions, CVC3::CDList< T >::end(), CVC3::Theorem::getExpr(), CVC3::Expr::isUserAssumption(), and CVC3::CDList< T >::push_back().

bool SearchSat::isAssumption ( const Expr e  )  [virtual]

Check if the formula has already been assumed previously.

Implements CVC3::SearchEngine.

Definition at line 1162 of file search_sat.cpp.

References CVC3::Expr::isIntAssumption(), and CVC3::Expr::isUserAssumption().

Referenced by newUserAssumptionInt().

void SearchSat::getCounterExample ( std::vector< Expr > &  assertions,
bool  inOrder = true 
) [virtual]

Will return the set of assertions which make the queried formula false.

This method should only be called after an query which returns INVALID. It will try to return the simplest possible set of assertions which are sufficient to make the queried expression false.

Parameters:
assertions should be empty on entry.
inOrder if true, returns the assertions in the order they were asserted. This is slightly more expensive than inOrder = false.

Implements CVC3::SearchEngine.

Definition at line 1168 of file search_sat.cpp.

References d_lastValid, CVC3::CDO< T >::get(), getInternalAssumptions(), and CVC3::Theorem::isNull().

Proof SearchSat::getProof (  )  [virtual]

Returns the proof term for the last proven query.

It should be called only after a query which returns VALID. In any other case, it returns Null.

Implements CVC3::SearchEngine.

Definition at line 1177 of file search_sat.cpp.

References CVC3::SearchEngine::d_core, d_lastValid, CVC3::CDO< T >::get(), CVC3::Theorem::getProof(), CVC3::TheoryCore::getTM(), CVC3::Theorem::isNull(), and CVC3::TheoremManager::withProof().

virtual FormulaValue CVC3::SearchSat::getValue ( const CVC3::Expr e  )  [inline, virtual]


Friends And Related Function Documentation

friend class Restorer [friend]

Helper class for resetting DPLLT engine.

We need to be notified when the scope goes below the scope from which the last invalid call to checkValid originated. This helper class ensures that this happens.

Definition at line 158 of file search_sat.h.

friend class SearchSatCoreSatAPI [friend]

Definition at line 179 of file search_sat.h.

Referenced by SearchSat().

friend class SearchSatCNFCallback [friend]

Definition at line 180 of file search_sat.h.

Referenced by SearchSat().

friend class SearchSatTheoryAPI [friend]

Definition at line 188 of file search_sat.h.

Referenced by SearchSat().

friend class SearchSatDecider [friend]

Definition at line 200 of file search_sat.h.

Referenced by SearchSat().


Member Data Documentation

std::string CVC3::SearchSat::d_name [private]

Name of search engine.

Definition at line 43 of file search_sat.h.

Referenced by getName().

Bottom scope for current query.

Definition at line 46 of file search_sat.h.

Referenced by check(), getBottomScope(), newUserAssumptionInt(), recordNewRootLit(), restorePre(), and returnFromCheck().

Last expr checked for validity.

Definition at line 49 of file search_sat.h.

Referenced by check().

Theorem from the last successful checkValid call. It is used by getProof and getAssumptions.

Definition at line 53 of file search_sat.h.

Referenced by check(), getCounterExample(), getProof(), and lastThm().

List of all user assumptions.

Definition at line 56 of file search_sat.h.

Referenced by getAssumptions(), getUserAssumptions(), and newUserAssumptionInt().

List of all internal assumptions.

Definition at line 59 of file search_sat.h.

Referenced by assertLit(), getAssumptions(), and getInternalAssumptions().

Index to where unprocessed assumptions start.

Definition at line 62 of file search_sat.h.

Definition at line 64 of file search_sat.h.

Referenced by SearchSat(), and ~SearchSat().

Pointer to DPLLT implementation.

Definition at line 67 of file search_sat.h.

Referenced by check(), newUserAssumption(), pop(), push(), SearchSat(), and ~SearchSat().

Implementation of TheoryAPI for DPLLT.

Definition at line 70 of file search_sat.h.

Referenced by SearchSat(), and ~SearchSat().

Implementation of Decider for DPLLT.

Definition at line 73 of file search_sat.h.

Referenced by SearchSat(), and ~SearchSat().

Store of theorems for expressions sent to DPLLT.

Definition at line 76 of file search_sat.h.

Referenced by getExplanation(), and getImplication().

Callback for CNF_Manager.

Definition at line 82 of file search_sat.h.

Referenced by SearchSat(), and ~SearchSat().

std::vector<SAT::Var::Val> CVC3::SearchSat::d_vars [private]

Cached values of variables.

Definition at line 85 of file search_sat.h.

Referenced by checkConsistent(), getExplanation(), getNewClauses(), getValue(), newUserAssumptionInt(), restore(), and setValue().

Whether we are currently in a call to dpllt->checkSat.

Definition at line 88 of file search_sat.h.

Referenced by check(), checkConsistent(), makeDecision(), and newUserAssumptionInt().

CNF Formula used for theory lemmas.

Definition at line 91 of file search_sat.h.

Referenced by check(), checkConsistent(), and getNewClauses().

std::vector<std::pair<Theorem, int> > CVC3::SearchSat::d_pendingLemmas [private]

Lemmas waiting to be translated since last call to getNewClauses().

Definition at line 94 of file search_sat.h.

Referenced by addLemma(), checkConsistent(), getNewClauses(), and restore().

std::vector<bool> CVC3::SearchSat::d_pendingScopes [private]

Scope parameter for lemmas waiting to be translated since last call to getNewClauses().

Definition at line 97 of file search_sat.h.

Referenced by addLemma(), getNewClauses(), and restore().

Backtracking size of d_pendingLemmas.

Definition at line 100 of file search_sat.h.

Referenced by addLemma(), and restore().

Backtracking next item in d_pendingLemmas.

Definition at line 103 of file search_sat.h.

Referenced by addLemma(), checkConsistent(), and getNewClauses().

CDO<unsigned> CVC3::SearchSat::d_lemmasNext [private]

Current position in d_lemmas.

Definition at line 106 of file search_sat.h.

Referenced by check(), checkConsistent(), and getNewClauses().

std::vector<unsigned> CVC3::SearchSat::d_varsUndoList [private]

List for backtracking var values.

Definition at line 109 of file search_sat.h.

Referenced by restore(), and setValue().

Backtracking size of d_varsUndoList.

Definition at line 112 of file search_sat.h.

Referenced by restore(), and setValue().

Used to determine order to find splitters.

Definition at line 131 of file search_sat.h.

Referenced by makeDecision(), recordNewRootLit(), restore(), restorePre(), and SearchSat().

CDO<std::set<LitPriorityPair>::const_iterator> CVC3::SearchSat::d_prioritySetStart [private]

Current position in prioritySet.

Definition at line 133 of file search_sat.h.

Referenced by makeDecision(), recordNewRootLit(), and SearchSat().

Backtracking size of priority set entries.

Definition at line 135 of file search_sat.h.

Referenced by recordNewRootLit(), and restore().

std::vector<std::set<LitPriorityPair>::iterator> CVC3::SearchSat::d_prioritySetEntries [private]

Entries in priority set in insertion order (so set can be backtracked).

Definition at line 137 of file search_sat.h.

Referenced by recordNewRootLit(), and restore().

Backtracking size of priority set entries at bottom scope.

Definition at line 139 of file search_sat.h.

Referenced by check(), and restorePre().

Current size of bottom entries.

Definition at line 141 of file search_sat.h.

Referenced by check(), recordNewRootLit(), and restorePre().

std::vector<std::set<LitPriorityPair>::iterator> CVC3::SearchSat::d_prioritySetBottomEntries [private]

Entries in priority set in insertion order (so set can be backtracked).

Definition at line 143 of file search_sat.h.

Referenced by recordNewRootLit(), and restorePre().

Last Var registered with core theory.

Definition at line 146 of file search_sat.h.

Whether it's OK to call DPLLT solver from the current scope.

Definition at line 149 of file search_sat.h.

Referenced by check().

Definition at line 151 of file search_sat.h.

Referenced by getImpliedLiteral().

Instance of Restorer class.

Definition at line 168 of file search_sat.h.


The documentation for this class was generated from the following files:

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