src/Backend/satorderencoder.cc

   1 #include "satencoder.h"
   2 #include "structs.h"
   3 #include "common.h"
   4 #include "order.h"
   5 #include "csolver.h"
   6 #include "orderpair.h"
   7 #include "set.h"
   8 #include "tunable.h"
   9 #include "orderanalysis.h"
  10 #include "ordergraph.h"
  11 #include "orderedge.h"
  12 #include "element.h"
  13 #include "predicate.h"
  14 #include "orderelement.h"
  15
  16 Edge SATEncoder::encodeOrderSATEncoder(BooleanOrder *constraint) {
  17         switch ( constraint->order->type) {
  18         case SATC_PARTIAL:
  19                 return encodePartialOrderSATEncoder(constraint);
  20         case SATC_TOTAL:
  21                 return encodeTotalOrderSATEncoder(constraint);
  22         default:
  23                 ASSERT(0);
  24         }
  25         return E_BOGUS;
  26 }
  27
  28 Edge SATEncoder::inferOrderConstraintFromGraph(Order *order, uint64_t _first, uint64_t _second) {
  29         if (order->graph != NULL) {
  30                 OrderGraph *graph = order->graph;
  31                 OrderNode *first = graph->lookupOrderNodeFromOrderGraph(_first);
  32                 OrderNode *second = graph->lookupOrderNodeFromOrderGraph(_second);
  33                 if ((first != NULL) && (second != NULL)) {
  34                         OrderEdge *edge = graph->lookupOrderEdgeFromOrderGraph(first, second);
  35                         if (edge != NULL) {
  36                                 if (edge->mustPos)
  37                                         return E_True;
  38                                 else if (edge->mustNeg)
  39                                         return E_False;
  40                         }
  41                         OrderEdge *invedge = graph->lookupOrderEdgeFromOrderGraph(second, first);
  42                         if (invedge != NULL) {
  43                                 if (invedge->mustPos)
  44                                         return E_False;
  45                                 else if (invedge->mustNeg)
  46                                         return E_True;
  47                         }
  48                 }
  49         }
  50         return E_NULL;
  51 }
  52
  53 Edge SATEncoder::getPairConstraint(Order *order, OrderPair *pair) {
  54         Edge gvalue = inferOrderConstraintFromGraph(order, pair->first, pair->second);
  55         if (!edgeIsNull(gvalue))
  56                 return gvalue;
  57
  58         HashtableOrderPair *table = order->orderPairTable;
  59         bool negate = false;
  60         OrderPair flipped;
  61         if (pair->first < pair->second) {
  62                 negate = true;
  63                 flipped.first = pair->second;
  64                 flipped.second = pair->first;
  65                 pair = &flipped;
  66         }
  67         Edge constraint;
  68         if (!(table->contains(pair))) {
  69                 constraint = getNewVarSATEncoder();
  70                 OrderPair *paircopy = new OrderPair(pair->first, pair->second, constraint);
  71                 table->put(paircopy, paircopy);
  72         } else
  73                 constraint = table->get(pair)->constraint;
  74
  75         return negate ? constraintNegate(constraint) : constraint;
  76 }
  77
  78 Edge SATEncoder::encodeTotalOrderSATEncoder(BooleanOrder *boolOrder) {
  79         ASSERT(boolOrder->order->type == SATC_TOTAL);
  80         if (boolOrder->order->orderPairTable == NULL) {
  81                 boolOrder->order->initializeOrderHashtable();
  82                 bool doOptOrderStructure = GETVARTUNABLE(solver->getTuner(), boolOrder->order->type, OPTIMIZEORDERSTRUCTURE, &onoff);
  83                 if (doOptOrderStructure) {
  84                         boolOrder->order->graph = buildMustOrderGraph(boolOrder->order);
  85                         reachMustAnalysis(solver, boolOrder->order->graph, true);
  86                 }
  87                 createAllTotalOrderConstraintsSATEncoder(boolOrder->order);
  88         }
  89         OrderPair pair(boolOrder->first, boolOrder->second, E_NULL);
  90         Edge constraint = getPairConstraint(boolOrder->order, &pair);
  91         return constraint;
  92 }
  93
  94
  95 void SATEncoder::createAllTotalOrderConstraintsSATEncoder(Order *order) {
  96 #ifdef CONFIG_DEBUG
  97         model_print("in total order ...\n");
  98 #endif
  99         ASSERT(order->type == SATC_TOTAL);
 100         Set *set = order->set;
 101         uint size = order->set->getSize();
 102         for (uint i = 0; i < size; i++) {
 103                 uint64_t valueI = set->getMemberAt(i);
 104                 for (uint j = i + 1; j < size; j++) {
 105                         uint64_t valueJ = set->getMemberAt(j);
 106                         OrderPair pairIJ(valueI, valueJ, E_NULL);
 107                         Edge constIJ = getPairConstraint(order, &pairIJ);
 108                         for (uint k = j + 1; k < size; k++) {
 109                                 uint64_t valueK = set->getMemberAt(k);
 110                                 OrderPair pairJK(valueJ, valueK, E_NULL);
 111                                 OrderPair pairIK(valueI, valueK, E_NULL);
 112                                 Edge constIK = getPairConstraint(order, &pairIK);
 113                                 Edge constJK = getPairConstraint(order, &pairJK);
 114                                 addConstraintCNF(cnf, generateTransOrderConstraintSATEncoder(constIJ, constJK, constIK));
 115                         }
 116                 }
 117         }
 118 }
 119
 120 Edge getOrderConstraint(HashtableOrderPair *table, OrderPair *pair) {
 121         ASSERT(pair->first != pair->second);
 122         bool negate = false;
 123         OrderPair flipped;
 124         if (pair->first < pair->second) {
 125                 negate = true;
 126                 flipped.first = pair->second;
 127                 flipped.second = pair->first;
 128                 pair = &flipped;
 129         }
 130         if (!table->contains(pair)) {
 131                 return E_NULL;
 132         }
 133         Edge constraint = table->get(pair)->constraint;
 134         ASSERT(!edgeIsNull(constraint));
 135         return negate ? constraintNegate(constraint) : constraint;
 136 }
 137
 138 Edge SATEncoder::generateTransOrderConstraintSATEncoder(Edge constIJ,Edge constJK,Edge constIK) {
 139         Edge carray[] = {constIJ, constJK, constraintNegate(constIK)};
 140         Edge loop1 = constraintOR(cnf, 3, carray);
 141         Edge carray2[] = {constraintNegate(constIJ), constraintNegate(constJK), constIK};
 142         Edge loop2 = constraintOR(cnf, 3, carray2 );
 143         return constraintAND2(cnf, loop1, loop2);
 144 }
 145
 146 Edge SATEncoder::encodePartialOrderSATEncoder(BooleanOrder *constraint) {
 147         ASSERT(constraint->order->type == SATC_PARTIAL);
 148         return E_BOGUS;
 149 }