src/decision/decision_engine.cpp

   1 /*********************                                                        */
   2 /*! \file decision_engine.cpp
   3  ** \verbatim
   4  ** Original author: kshitij
   5  ** Major contributors: none
   6  ** Minor contributors (to current version): taking, mdeters
   7  ** This file is part of the CVC4 prototype.
   8  ** Copyright (c) 2009-2012  New York University and The University of Iowa
   9  ** See the file COPYING in the top-level source directory for licensing
  10  ** information.\endverbatim
  11  **
  12  ** \brief Decision engine
  13  **
  14  ** Decision engine
  15  **/
  16
  17 #include "decision/decision_engine.h"
  18 #include "decision/justification_heuristic.h"
  19 #include "decision/relevancy.h"
  20
  21 #include "expr/node.h"
  22 #include "decision/options.h"
  23 #include "decision/decision_mode.h"
  24
  25 #include "smt/options.h"
  26
  27 using namespace std;
  28
  29 namespace CVC4 {
  30
  31 DecisionEngine::DecisionEngine(context::Context *sc,
  32                                  context::Context *uc) :
  33   d_enabledStrategies(),
  34   d_needIteSkolemMap(),
  35   d_relevancyStrategy(NULL),
  36   d_assertions(uc),
  37   d_cnfStream(NULL),
  38   d_satSolver(NULL),
  39   d_satContext(sc),
  40   d_userContext(uc),
  41   d_result(sc, SAT_VALUE_UNKNOWN),
  42   d_engineState(0)
  43 {
  44   Trace("decision") << "Creating decision engine" << std::endl;
  45 }
  46
  47 void DecisionEngine::init()
  48 {
  49   Assert(d_engineState == 0);
  50   d_engineState = 1;
  51
  52   Trace("decision-init") << "DecisionEngine::init()" << std::endl;
  53   Trace("decision-init") << " * options->decisionMode: "
  54                          << options::decisionMode() << std:: endl;
  55   Trace("decision-init") << " * options->decisionStopOnly: "
  56                          << options::decisionStopOnly() << std::endl;
  57
  58   if(options::decisionMode() == decision::DECISION_STRATEGY_INTERNAL) { }
  59   if(options::decisionMode() == decision::DECISION_STRATEGY_JUSTIFICATION) {
  60     ITEDecisionStrategy* ds =
  61       new decision::JustificationHeuristic(this, d_userContext, d_satContext);
  62     enableStrategy(ds);
  63     d_needIteSkolemMap.push_back(ds);
  64   }
  65   if(options::decisionMode() == decision::DECISION_STRATEGY_RELEVANCY) {
  66     if(options::incrementalSolving()) {
  67       Warning() << "Relevancy decision heuristic and incremental not supported together"
  68                 << std::endl;
  69       return; // Currently not supported with incremental
  70     }
  71     RelevancyStrategy* ds =
  72       new decision::Relevancy(this, d_satContext);
  73     enableStrategy(ds);
  74     d_needIteSkolemMap.push_back(ds);
  75     d_relevancyStrategy = ds;
  76   }
  77 }
  78
  79
  80 void DecisionEngine::enableStrategy(DecisionStrategy* ds)
  81 {
  82   d_enabledStrategies.push_back(ds);
  83 }
  84
  85
  86 bool DecisionEngine::isRelevant(SatVariable var)
  87 {
  88   Debug("decision") << "isRelevant(" << var <<")" << std::endl;
  89   if(d_relevancyStrategy != NULL) {
  90     //Assert(d_cnfStream->hasNode(var));
  91     return d_relevancyStrategy->isRelevant( d_cnfStream->getNode(SatLiteral(var)) );
  92   } else {
  93     return true;
  94   }
  95 }
  96
  97 SatValue DecisionEngine::getPolarity(SatVariable var)
  98 {
  99   Debug("decision") << "getPolariry(" << var <<")" << std::endl;
 100   if(d_relevancyStrategy != NULL) {
 101     Assert(isRelevant(var));
 102     return d_relevancyStrategy->getPolarity( d_cnfStream->getNode(SatLiteral(var)) );
 103   } else {
 104     return SAT_VALUE_UNKNOWN;
 105   }
 106 }
 107
 108
 109
 110
 111
 112
 113
 114
 115 void DecisionEngine::addAssertions(const vector<Node> &assertions)
 116 {
 117   Assert(false);  // doing this so that we revisit what to do
 118                   // here. Currently not being used.
 119
 120   // d_result = SAT_VALUE_UNKNOWN;
 121   // d_assertions.reserve(assertions.size());
 122   // for(unsigned i = 0; i < assertions.size(); ++i)
 123   //   d_assertions.push_back(assertions[i]);
 124 }
 125
 126 void DecisionEngine::addAssertions(const vector<Node> &assertions,
 127                                    unsigned assertionsEnd,
 128                                    IteSkolemMap iteSkolemMap)
 129 {
 130   // new assertions, reset whatever result we knew
 131   d_result = SAT_VALUE_UNKNOWN;
 132
 133   // d_assertions.reserve(assertions.size());
 134   for(unsigned i = 0; i < assertions.size(); ++i)
 135     d_assertions.push_back(assertions[i]);
 136
 137   for(unsigned i = 0; i < d_needIteSkolemMap.size(); ++i)
 138     d_needIteSkolemMap[i]->
 139       addAssertions(assertions, assertionsEnd, iteSkolemMap);
 140 }
 141
 142 // void DecisionEngine::addAssertion(Node n)
 143 // {
 144 //   d_result = SAT_VALUE_UNKNOWN;
 145 //   if(needIteSkolemMap()) {
 146 //     d_assertions.push_back(n);
 147 //   }
 148 //   for(unsigned i = 0; i < d_needIteSkolemMap.size(); ++i)
 149 //     d_needIteSkolemMap[i]->notifyAssertionsAvailable();
 150 // }
 151
 152
 153 }/* CVC4 namespace */