src/Backend/satfuncopencoder.c

   1 #include "satencoder.h"
   2 #include "common.h"
   3 #include "function.h"
   4 #include "ops.h"
   5 #include "predicate.h"
   6 #include "boolean.h"
   7 #include "table.h"
   8 #include "tableentry.h"
   9 #include "set.h"
  10 #include "element.h"
  11 #include "common.h"
  12 #include "satfuncopencoder.h"
  13
  14 Edge encodeOperatorPredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint) {
  15         switch(constraint->encoding.type){
  16                 case ENUMERATEIMPLICATIONS:
  17                         return encodeEnumOperatorPredicateSATEncoder(This, constraint);
  18                 case CIRCUIT:
  19                         return encodeCircuitOperatorPredicateEncoder(This, constraint);
  20                 default:
  21                         ASSERT(0);
  22         }
  23         exit(-1);
  24 }
  25
  26 Edge encodeEnumOperatorPredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint) {
  27         PredicateOperator* predicate = (PredicateOperator*)constraint->predicate;
  28         uint numDomains=getSizeArraySet(&predicate->domains);
  29
  30         FunctionEncodingType encType = constraint->encoding.type;
  31         bool generateNegation = encType == ENUMERATEIMPLICATIONSNEGATE;
  32
  33         /* Call base encoders for children */
  34         for(uint i=0;i<numDomains;i++) {
  35                 Element *elem = getArrayElement( &constraint->inputs, i);
  36                 encodeElementSATEncoder(This, elem);
  37         }
  38         VectorEdge * clauses=allocDefVectorEdge(); // Setup array of clauses
  39
  40         uint indices[numDomains]; //setup indices
  41         bzero(indices, sizeof(uint)*numDomains);
  42
  43         uint64_t vals[numDomains]; //setup value array
  44         for(uint i=0;i<numDomains; i++) {
  45                 Set * set=getArraySet(&predicate->domains, i);
  46                 vals[i]=getSetElement(set, indices[i]);
  47         }
  48
  49         bool notfinished=true;
  50         while(notfinished) {
  51                 Edge carray[numDomains];
  52
  53                 if (evalPredicateOperator(predicate, vals) ^ generateNegation) {
  54                         //Include this in the set of terms
  55                         for(uint i=0;i<numDomains;i++) {
  56                                 Element * elem = getArrayElement(&constraint->inputs, i);
  57                                 carray[i] = getElementValueConstraint(This, elem, vals[i]);
  58                         }
  59                         Edge term=constraintAND(This->cnf, numDomains, carray);
  60                         pushVectorEdge(clauses, term);
  61                 }
  62
  63                 notfinished=false;
  64                 for(uint i=0;i<numDomains; i++) {
  65                         uint index=++indices[i];
  66                         Set * set=getArraySet(&predicate->domains, i);
  67
  68                         if (index < getSetSize(set)) {
  69                                 vals[i]=getSetElement(set, index);
  70                                 notfinished=true;
  71                                 break;
  72                         } else {
  73                                 indices[i]=0;
  74                                 vals[i]=getSetElement(set, 0);
  75                         }
  76                 }
  77         }
  78         if(getSizeVectorEdge(clauses) == 0) {
  79                 deleteVectorEdge(clauses);
  80                 return E_False;
  81         }
  82         Edge cor=constraintOR(This->cnf, getSizeVectorEdge(clauses), exposeArrayEdge(clauses));
  83         deleteVectorEdge(clauses);
  84         return generateNegation ? constraintNegate(cor) : cor;
  85 }
  86
  87
  88 void encodeOperatorElementFunctionSATEncoder(SATEncoder* This, ElementFunction* func) {
  89 #ifdef TRACE_DEBUG
  90         model_print("Operator Function ...\n");
  91 #endif
  92         FunctionOperator * function = (FunctionOperator *) func->function;
  93         uint numDomains=getSizeArrayElement(&func->inputs);
  94
  95         /* Call base encoders for children */
  96         for(uint i=0;i<numDomains;i++) {
  97                 Element *elem = getArrayElement( &func->inputs, i);
  98                 encodeElementSATEncoder(This, elem);
  99         }
 100
 101         VectorEdge * clauses=allocDefVectorEdge(); // Setup array of clauses
 102
 103         uint indices[numDomains]; //setup indices
 104         bzero(indices, sizeof(uint)*numDomains);
 105
 106         uint64_t vals[numDomains]; //setup value array
 107         for(uint i=0;i<numDomains; i++) {
 108                 Set * set=getElementSet(getArrayElement(&func->inputs, i));
 109                 vals[i]=getSetElement(set, indices[i]);
 110         }
 111
 112         Edge overFlowConstraint = ((BooleanVar*) func->overflowstatus)->var;
 113
 114         bool notfinished=true;
 115         while(notfinished) {
 116                 Edge carray[numDomains+1];
 117
 118                 uint64_t result=applyFunctionOperator(function, numDomains, vals);
 119                 bool isInRange = isInRangeFunction((FunctionOperator*)func->function, result);
 120                 bool needClause = isInRange;
 121                 if (function->overflowbehavior == OVERFLOWSETSFLAG || function->overflowbehavior == FLAGIFFOVERFLOW) {
 122                         needClause=true;
 123                 }
 124
 125                 if (needClause) {
 126                         //Include this in the set of terms
 127                         for(uint i=0;i<numDomains;i++) {
 128                                 Element * elem = getArrayElement(&func->inputs, i);
 129                                 carray[i] = getElementValueConstraint(This, elem, vals[i]);
 130                         }
 131                         if (isInRange) {
 132                                 carray[numDomains] = getElementValueConstraint(This, &func->base, result);
 133                         }
 134
 135                         Edge clause;
 136                         switch(function->overflowbehavior) {
 137                         case IGNORE:
 138                         case NOOVERFLOW:
 139                         case WRAPAROUND: {
 140                                 clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), carray[numDomains]);
 141                                 break;
 142                         }
 143                         case FLAGFORCESOVERFLOW: {
 144                                 clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), constraintAND2(This->cnf, carray[numDomains], constraintNegate(overFlowConstraint)));
 145                                 break;
 146                         }
 147                         case OVERFLOWSETSFLAG: {
 148                                 if (isInRange) {
 149                                         clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), carray[numDomains]);
 150                                 } else {
 151                                         clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), overFlowConstraint);
 152                                 }
 153                                 break;
 154                         }
 155                         case FLAGIFFOVERFLOW: {
 156                                 if (isInRange) {
 157                                         clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), constraintAND2(This->cnf, carray[numDomains], constraintNegate(overFlowConstraint)));
 158                                 } else {
 159                                         clause=constraintIMPLIES(This->cnf,constraintAND(This->cnf, numDomains, carray), overFlowConstraint);
 160                                 }
 161                                 break;
 162                         }
 163                         default:
 164                                 ASSERT(0);
 165                         }
 166 #ifdef TRACE_DEBUG
 167                         model_print("added clause in operator function\n");
 168                         printCNF(clause);
 169                         model_print("\n");
 170 #endif
 171                         pushVectorEdge(clauses, clause);
 172                 }
 173
 174                 notfinished=false;
 175                 for(uint i=0;i<numDomains; i++) {
 176                         uint index=++indices[i];
 177                         Set * set=getElementSet(getArrayElement(&func->inputs, i));
 178
 179                         if (index < getSetSize(set)) {
 180                                 vals[i]=getSetElement(set, index);
 181                                 notfinished=true;
 182                                 break;
 183                         } else {
 184                                 indices[i]=0;
 185                                 vals[i]=getSetElement(set, 0);
 186                         }
 187                 }
 188         }
 189
 190         Edge cor=constraintAND(This->cnf, getSizeVectorEdge(clauses), exposeArrayEdge(clauses));
 191         addConstraintCNF(This->cnf, cor);
 192         deleteVectorEdge(clauses);
 193 }
 194
 195 Edge encodeCircuitOperatorPredicateEncoder(SATEncoder *This, BooleanPredicate * constraint) {
 196         PredicateOperator * predicate = (PredicateOperator*) constraint->predicate;
 197
 198         switch(predicate->op) {
 199         case EQUALS: {
 200                 return encodeCircuitEquals(This, constraint);
 201         }
 202         default:
 203                 ASSERT(0);
 204         }
 205         exit(-1);
 206 }
 207
 208 Edge encodeCircuitEquals(SATEncoder * This, BooleanPredicate * constraint) {
 209         PredicateOperator * predicate = (PredicateOperator*) constraint->predicate;
 210         ASSERT(getSizeArraySet(&predicate->domains) == 2);
 211         Element *elem0 = getArrayElement( &constraint->inputs, 0);
 212         Element *elem1 = getArrayElement( &constraint->inputs, 1);
 213         ElementEncoding *ee0=getElementEncoding(elem0);
 214         ElementEncoding *ee1=getElementEncoding(elem1);
 215         ASSERT(ee0->numVars==ee1->numVars);
 216         uint numVars=ee0->numVars;
 217         Edge carray[numVars];
 218         for (uint i=0; i<numVars; i++) {
 219                 carray[i]=constraintIFF(This->cnf, ee0->variables[i], ee1->variables[i]);
 220         }
 221         return constraintAND(This->cnf, numVars, carray);
 222 }