src/Backend/satencoder.c

   1 #include "satencoder.h"
   2 #include "structs.h"
   3 #include "csolver.h"
   4 #include "boolean.h"
   5 #include "constraint.h"
   6 #include "common.h"
   7 #include "element.h"
   8 #include "function.h"
   9 #include "tableentry.h"
  10 #include "table.h"
  11 #include "order.h"
  12 #include "predicate.h"
  13 #include "orderpair.h"
  14 #include "set.h"
  15
  16 SATEncoder * allocSATEncoder() {
  17         SATEncoder *This=ourmalloc(sizeof (SATEncoder));
  18         This->varcount=1;
  19         return This;
  20 }
  21
  22 void deleteSATEncoder(SATEncoder *This) {
  23         ourfree(This);
  24 }
  25
  26 Constraint * getElementValueConstraint(Element* This, uint64_t value) {
  27         switch(getElementEncoding(This)->type){
  28                 case ONEHOT:
  29                         ASSERT(0);
  30                         break;
  31                 case UNARY:
  32                         ASSERT(0);
  33                         break;
  34                 case BINARYINDEX:
  35                         ASSERT(0);
  36                         break;
  37                 case ONEHOTBINARY:
  38                         return getElementValueBinaryIndexConstraint(This, value);
  39                         break;
  40                 case BINARYVAL:
  41                         ASSERT(0);
  42                         break;
  43                 default:
  44                         ASSERT(0);
  45                         break;
  46         }
  47         return NULL;
  48 }
  49 Constraint * getElementValueBinaryIndexConstraint(Element* This, uint64_t value) {
  50         ASTNodeType type = GETELEMENTTYPE(This);
  51         ASSERT(type == ELEMSET || type == ELEMFUNCRETURN);
  52         ElementEncoding* elemEnc = getElementEncoding(This);
  53         for(uint i=0; i<elemEnc->encArraySize; i++){
  54                 if( isinUseElement(elemEnc, i) && elemEnc->encodingArray[i]==value){
  55                         return generateBinaryConstraint(elemEnc->numVars,
  56                                 elemEnc->variables, i);
  57                 }
  58         }
  59         return NULL;
  60 }
  61
  62 void encodeAllSATEncoder(CSolver *csolver, SATEncoder * This) {
  63         VectorBoolean *constraints=csolver->constraints;
  64         uint size=getSizeVectorBoolean(constraints);
  65         for(uint i=0;i<size;i++) {
  66                 Boolean *constraint=getVectorBoolean(constraints, i);
  67                 Constraint* c= encodeConstraintSATEncoder(This, constraint);
  68                 printConstraint(c);
  69         }
  70 }
  71
  72 Constraint * encodeConstraintSATEncoder(SATEncoder *This, Boolean *constraint) {
  73         switch(GETBOOLEANTYPE(constraint)) {
  74         case ORDERCONST:
  75                 return encodeOrderSATEncoder(This, (BooleanOrder *) constraint);
  76         case BOOLEANVAR:
  77                 return encodeVarSATEncoder(This, (BooleanVar *) constraint);
  78         case LOGICOP:
  79                 return encodeLogicSATEncoder(This, (BooleanLogic *) constraint);
  80         case PREDICATEOP:
  81                 return encodePredicateSATEncoder(This, (BooleanPredicate *) constraint);
  82         default:
  83                 model_print("Unhandled case in encodeConstraintSATEncoder %u", GETBOOLEANTYPE(constraint));
  84                 exit(-1);
  85         }
  86 }
  87
  88 void getArrayNewVarsSATEncoder(SATEncoder* encoder, uint num, Constraint **carray) {
  89         for(uint i=0;i<num;i++)
  90                 carray[i]=getNewVarSATEncoder(encoder);
  91 }
  92
  93 Constraint * getNewVarSATEncoder(SATEncoder *This) {
  94         Constraint * var=allocVarConstraint(VAR, This->varcount);
  95         Constraint * varneg=allocVarConstraint(NOTVAR, This->varcount++);
  96         setNegConstraint(var, varneg);
  97         setNegConstraint(varneg, var);
  98         return var;
  99 }
 100
 101 Constraint * encodeVarSATEncoder(SATEncoder *This, BooleanVar * constraint) {
 102         if (constraint->var == NULL) {
 103                 constraint->var=getNewVarSATEncoder(This);
 104         }
 105         return constraint->var;
 106 }
 107
 108 Constraint * encodeLogicSATEncoder(SATEncoder *This, BooleanLogic * constraint) {
 109         Constraint * array[getSizeArrayBoolean(&constraint->inputs)];
 110         for(uint i=0;i<getSizeArrayBoolean(&constraint->inputs);i++)
 111                 array[i]=encodeConstraintSATEncoder(This, getArrayBoolean(&constraint->inputs, i));
 112
 113         switch(constraint->op) {
 114         case L_AND:
 115                 return allocArrayConstraint(AND, getSizeArrayBoolean(&constraint->inputs), array);
 116         case L_OR:
 117                 return allocArrayConstraint(OR, getSizeArrayBoolean(&constraint->inputs), array);
 118         case L_NOT:
 119                 ASSERT( getSizeArrayBoolean(&constraint->inputs)==1);
 120                 return negateConstraint(array[0]);
 121         case L_XOR: {
 122                 ASSERT( getSizeArrayBoolean(&constraint->inputs)==2);
 123                 Constraint * nleft=negateConstraint(cloneConstraint(array[0]));
 124                 Constraint * nright=negateConstraint(cloneConstraint(array[1]));
 125                 return allocConstraint(OR,
 126                                                                                                          allocConstraint(AND, array[0], nright),
 127                                                                                                          allocConstraint(AND, nleft, array[1]));
 128         }
 129         case L_IMPLIES:
 130                 ASSERT( getSizeArrayBoolean( &constraint->inputs)==2);
 131                 return allocConstraint(IMPLIES, array[0], array[1]);
 132         default:
 133                 model_print("Unhandled case in encodeLogicSATEncoder %u", constraint->op);
 134                 exit(-1);
 135         }
 136 }
 137
 138
 139 Constraint * encodeOrderSATEncoder(SATEncoder *This, BooleanOrder * constraint) {
 140         switch( constraint->order->type){
 141                 case PARTIAL:
 142                         return encodePartialOrderSATEncoder(This, constraint);
 143                 case TOTAL:
 144                         return encodeTotalOrderSATEncoder(This, constraint);
 145                 default:
 146                         ASSERT(0);
 147         }
 148         return NULL;
 149 }
 150
 151 Constraint * getPairConstraint(SATEncoder *This, HashTableBoolConst * table, OrderPair * pair) {
 152         bool negate = false;
 153         OrderPair flipped;
 154         if (pair->first > pair->second) {
 155                 negate=true;
 156                 flipped.first=pair->second;
 157                 flipped.second=pair->first;
 158                 pair = &flipped;
 159         }
 160         Constraint * constraint;
 161         if (!containsBoolConst(table, pair)) {
 162                 constraint = getNewVarSATEncoder(This);
 163                 OrderPair * paircopy = allocOrderPair(pair->first, pair->second);
 164                 putBoolConst(table, paircopy, constraint);
 165         } else
 166                 constraint = getBoolConst(table, pair);
 167         if (negate)
 168                 return negateConstraint(constraint);
 169         else
 170                 return constraint;
 171
 172 }
 173
 174 Constraint * encodeTotalOrderSATEncoder(SATEncoder *This, BooleanOrder * boolOrder){
 175         ASSERT(boolOrder->order->type == TOTAL);
 176         HashTableBoolConst* boolToConsts = boolOrder->order->boolsToConstraints;
 177         OrderPair pair={boolOrder->first, boolOrder->second};
 178         Constraint* constraint = getPairConstraint(This, boolToConsts, & pair);
 179         ASSERT(constraint != NULL);
 180         return constraint;
 181 }
 182
 183 void createAllTotalOrderConstraintsSATEncoder(SATEncoder* This, Order* order){
 184         ASSERT(order->type == TOTAL);
 185         VectorInt* mems = order->set->members;
 186         HashTableBoolConst* table = order->boolsToConstraints;
 187         uint size = getSizeVectorInt(mems);
 188         for(uint i=0; i<size; i++){
 189                 uint64_t valueI = getVectorInt(mems, i);
 190                 for(uint j=i+1; j<size;j++){
 191                         uint64_t valueJ = getVectorInt(mems, j);
 192                         OrderPair pairIJ = {valueI, valueJ};
 193                         Constraint* constIJ=getPairConstraint(This, table, & pairIJ);
 194                         for(uint k=j+1; k<size; k++){
 195                                 uint64_t valueK = getVectorInt(mems, k);
 196                                 OrderPair pairJK = {valueJ, valueK};
 197                                 OrderPair pairIK = {valueI, valueK};
 198                                 Constraint* constIK = getPairConstraint(This, table, & pairIK);
 199                                 Constraint* constJK = getPairConstraint(This, table, & pairJK);
 200                                 generateTransOrderConstraintSATEncoder(This, constIJ, constJK, constIK);
 201                         }
 202                 }
 203         }
 204 }
 205
 206 Constraint* getOrderConstraint(HashTableBoolConst *table, OrderPair *pair){
 207         ASSERT(pair->first!= pair->second);
 208         Constraint* constraint= getBoolConst(table, pair);
 209         ASSERT(constraint!= NULL);
 210         if(pair->first > pair->second)
 211                 return constraint;
 212         else
 213                 return negateConstraint(constraint);
 214 }
 215
 216 Constraint * generateTransOrderConstraintSATEncoder(SATEncoder *This, Constraint *constIJ,Constraint *constJK,Constraint *constIK){
 217         //FIXME: first we should add the the constraint to the satsolver!
 218         ASSERT(constIJ!= NULL && constJK != NULL && constIK != NULL);
 219         Constraint *carray[] = {constIJ, constJK, negateConstraint(constIK)};
 220         Constraint * loop1= allocArrayConstraint(OR, 3, carray);
 221         Constraint * carray2[] = {negateConstraint(constIJ), negateConstraint(constJK), constIK};
 222         Constraint * loop2= allocArrayConstraint(OR, 3,carray2 );
 223         return allocConstraint(AND, loop1, loop2);
 224 }
 225
 226 Constraint * encodePartialOrderSATEncoder(SATEncoder *This, BooleanOrder * constraint){
 227         // FIXME: we can have this implementation for partial order. Basically,
 228         // we compute the transitivity between two order constraints specified by the client! (also can be used
 229         // when client specify sparse constraints for the total order!)
 230         ASSERT(constraint->order->type == PARTIAL);
 231 /*
 232         HashTableBoolConst* boolToConsts = boolOrder->order->boolsToConstraints;
 233         if( containsBoolConst(boolToConsts, boolOrder) ){
 234                 return getBoolConst(boolToConsts, boolOrder);
 235         } else {
 236                 Constraint* constraint = getNewVarSATEncoder(This);
 237                 putBoolConst(boolToConsts,boolOrder, constraint);
 238                 VectorBoolean* orderConstrs = &boolOrder->order->constraints;
 239                 uint size= getSizeVectorBoolean(orderConstrs);
 240                 for(uint i=0; i<size; i++){
 241                         ASSERT(GETBOOLEANTYPE( getVectorBoolean(orderConstrs, i)) == ORDERCONST );
 242                         BooleanOrder* tmp = (BooleanOrder*)getVectorBoolean(orderConstrs, i);
 243                         BooleanOrder* newBool;
 244                         Constraint* first, *second;
 245                         if(tmp->second==boolOrder->first){
 246                                 newBool = (BooleanOrder*)allocBooleanOrder(tmp->order,tmp->first,boolOrder->second);
 247                                 first = encodeTotalOrderSATEncoder(This, tmp);
 248                                 second = constraint;
 249
 250                         }else if (boolOrder->second == tmp->first){
 251                                 newBool = (BooleanOrder*)allocBooleanOrder(tmp->order,boolOrder->first,tmp->second);
 252                                 first = constraint;
 253                                 second = encodeTotalOrderSATEncoder(This, tmp);
 254                         }else
 255                                 continue;
 256                         Constraint* transConstr= encodeTotalOrderSATEncoder(This, newBool);
 257                         generateTransOrderConstraintSATEncoder(This, first, second, transConstr );
 258                 }
 259                 return constraint;
 260         }
 261 */
 262         return NULL;
 263 }
 264
 265 Constraint * encodePredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint) {
 266         switch(GETPREDICATETYPE(constraint->predicate) ){
 267                 case TABLEPRED:
 268                         return encodeTablePredicateSATEncoder(This, constraint);
 269                 case OPERATORPRED:
 270                         return encodeOperatorPredicateSATEncoder(This, constraint);
 271                 default:
 272                         ASSERT(0);
 273         }
 274         return NULL;
 275 }
 276
 277 Constraint * encodeTablePredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint){
 278         switch(constraint->encoding.type){
 279                 case ENUMERATEIMPLICATIONS:
 280                 case ENUMERATEIMPLICATIONSNEGATE:
 281                         return encodeEnumTablePredicateSATEncoder(This, constraint);
 282                 case CIRCUIT:
 283                         ASSERT(0);
 284                         break;
 285                 default:
 286                         ASSERT(0);
 287         }
 288         return NULL;
 289 }
 290
 291 Constraint * encodeEnumTablePredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint){
 292         VectorTableEntry* entries = &(((PredicateTable*)constraint->predicate)->table->entries);
 293         FunctionEncodingType encType = constraint->encoding.type;
 294         uint size = getSizeVectorTableEntry(entries);
 295         Constraint* constraints[size];
 296         for(uint i=0; i<size; i++){
 297                 TableEntry* entry = getVectorTableEntry(entries, i);
 298                 if(encType==ENUMERATEIMPLICATIONS && entry->output!= true)
 299                         continue;
 300                 else if(encType==ENUMERATEIMPLICATIONSNEGATE && entry->output !=false)
 301                         continue;
 302                 ArrayElement* inputs = &constraint->inputs;
 303                 uint inputNum =getSizeArrayElement(inputs);
 304                 Constraint* carray[inputNum];
 305                 for(uint j=0; j<inputNum; j++){
 306                         Element* el = getArrayElement(inputs, j);
 307                         if( GETELEMENTTYPE(el) == ELEMFUNCRETURN)
 308                                 encodeFunctionElementSATEncoder(This, (ElementFunction*) el);
 309                         carray[j] = getElementValueConstraint(el, entry->inputs[j]);
 310                         ASSERT(carray[j]!= NULL);
 311                 }
 312                 constraints[i]=allocArrayConstraint(AND, inputNum, carray);
 313         }
 314         Constraint* result= allocArrayConstraint(OR, size, constraints);
 315         //FIXME: if it didn't match with any entry
 316         return encType==ENUMERATEIMPLICATIONS? result: negateConstraint(result);
 317 }
 318
 319 Constraint * encodeOperatorPredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint){
 320         switch(constraint->encoding.type){
 321                 case ENUMERATEIMPLICATIONS:
 322                         return encodeEnumOperatorPredicateSATEncoder(This, constraint);
 323                 case CIRCUIT:
 324                         ASSERT(0);
 325                         break;
 326                 default:
 327                         ASSERT(0);
 328         }
 329         return NULL;
 330 }
 331
 332 Constraint * encodeEnumOperatorPredicateSATEncoder(SATEncoder * This, BooleanPredicate * constraint){
 333         ASSERT(GETPREDICATETYPE(constraint)==OPERATORPRED);
 334         PredicateOperator* predicate = (PredicateOperator*)constraint->predicate;
 335         ASSERT(predicate->op == EQUALS); //For now, we just only support equals
 336         //getting maximum size of in common elements between two sets!
 337         uint size=getSizeVectorInt( getArraySet( &predicate->domains, 0)->members);
 338         uint64_t commonElements [size];
 339         getEqualitySetIntersection(predicate, &size, commonElements);
 340         Constraint*  carray[size];
 341         Element* elem1 = getArrayElement( &constraint->inputs, 0);
 342         if( GETELEMENTTYPE(elem1) == ELEMFUNCRETURN)
 343                 encodeFunctionElementSATEncoder(This, (ElementFunction*) elem1);
 344         Element* elem2 = getArrayElement( &constraint->inputs, 1);
 345         if( GETELEMENTTYPE(elem2) == ELEMFUNCRETURN)
 346                 encodeFunctionElementSATEncoder(This, (ElementFunction*) elem2);
 347         for(uint i=0; i<size; i++){
 348                 Constraint* arg1 = getElementValueConstraint(elem1, commonElements[i]);
 349                 ASSERT(arg1!=NULL);
 350                 Constraint* arg2 = getElementValueConstraint(elem2, commonElements[i]);
 351                 ASSERT(arg2 != NULL);
 352                 carray[i] =  allocConstraint(AND, arg1, arg2);
 353         }
 354         //FIXME: the case when there is no intersection ....
 355         return allocArrayConstraint(OR, size, carray);
 356 }
 357
 358 Constraint* encodeFunctionElementSATEncoder(SATEncoder* encoder, ElementFunction *This){
 359         switch(GETFUNCTIONTYPE(This->function)){
 360                 case TABLEFUNC:
 361                         return encodeTableElementFunctionSATEncoder(encoder, This);
 362                 case OPERATORFUNC:
 363                         return encodeOperatorElementFunctionSATEncoder(encoder, This);
 364                 default:
 365                         ASSERT(0);
 366         }
 367         return NULL;
 368 }
 369
 370 Constraint* encodeTableElementFunctionSATEncoder(SATEncoder* encoder, ElementFunction* This){
 371         switch(getElementFunctionEncoding(This)->type){
 372                 case ENUMERATEIMPLICATIONS:
 373                         return encodeEnumTableElemFunctionSATEncoder(encoder, This);
 374                         break;
 375                 case CIRCUIT:
 376                         ASSERT(0);
 377                         break;
 378                 default:
 379                         ASSERT(0);
 380         }
 381         return NULL;
 382 }
 383
 384 Constraint* encodeOperatorElementFunctionSATEncoder(SATEncoder* encoder, ElementFunction* This){
 385         ASSERT(GETFUNCTIONTYPE(This->function) == OPERATORFUNC);
 386         ASSERT(getSizeArrayElement(&This->inputs)==2 );
 387         ElementEncoding* elem1 = getElementEncoding( getArrayElement(&This->inputs,0) );
 388         ElementEncoding* elem2 = getElementEncoding( getArrayElement(&This->inputs,1) );
 389         Constraint* carray[elem1->encArraySize*elem2->encArraySize];
 390         uint size=0;
 391         Constraint* overFlowConstraint = ((BooleanVar*) This->overflowstatus)->var;
 392         for(uint i=0; i<elem1->encArraySize; i++){
 393                 if(isinUseElement(elem1, i)){
 394                         for(uint j=0; j<elem2->encArraySize; j++){
 395                                 if(isinUseElement(elem2, j)){
 396                                         bool isInRange = false, hasOverFlow=false;
 397                                         uint64_t result= applyFunctionOperator((FunctionOperator*)This->function,elem1->encodingArray[i],
 398                                                 elem2->encodingArray[j], &isInRange, &hasOverFlow);
 399                                         if(!isInRange)
 400                                                 break; // Ignoring the cases that result of operation doesn't exist in the code.
 401                                         //FIXME: instead of getElementValueConstraint, it might be useful to have another function
 402                                         // that doesn't iterate over encodingArray and treats more efficient ...
 403                                         Constraint* and1 = getElementValueConstraint(elem1->element, elem1->encodingArray[i]);
 404                                         ASSERT(and1 != NULL);
 405                                         Constraint* and2 = getElementValueConstraint(elem2->element, elem2->encodingArray[j]);
 406                                         ASSERT(and2 != NULL);
 407                                         Constraint* imply2 = getElementValueConstraint((Element*) This, result);
 408                                         ASSERT(imply2 != NULL);
 409                                         Constraint* constraint = allocConstraint(IMPLIES,
 410                                                 allocConstraint(AND, and1, and2) , imply2);
 411                                         switch( ((FunctionOperator*)This->function)->overflowbehavior ){
 412                                                 case IGNORE:
 413                                                         if(!hasOverFlow){
 414                                                                 carray[size++] = constraint;
 415                                                         }
 416                                                 case WRAPAROUND:
 417                                                         carray[size++] = constraint;
 418                                                 case FLAGFORCESOVERFLOW:
 419                                                         if(hasOverFlow){
 420                                                                 Constraint* const1 = allocConstraint(IMPLIES, overFlowConstraint,
 421                                                                                 allocConstraint(AND, getElementValueConstraint(elem1->element, elem1->encodingArray[i]),
 422                                                                                 getElementValueConstraint(elem2->element, elem2->encodingArray[j])));
 423                                                                 carray[size++] = allocConstraint(AND, const1, constraint);
 424                                                         }
 425                                                 case OVERFLOWSETSFLAG:
 426                                                         if(hasOverFlow){
 427                                                                 Constraint* const1 = allocConstraint(IMPLIES, allocConstraint(AND, getElementValueConstraint(elem1->element, elem1->encodingArray[i]),
 428                                                                                 getElementValueConstraint(elem2->element, elem2->encodingArray[j])), overFlowConstraint);
 429                                                                 carray[size++] = allocConstraint(AND, const1, constraint);
 430                                                         } else
 431                                                                 carray[size++] = constraint;
 432                                                 case FLAGIFFOVERFLOW:
 433                                                         if(!hasOverFlow){
 434                                                                 carray[size++] = constraint;
 435                                                         }else{
 436                                                                 Constraint* const1 = allocConstraint(IMPLIES, overFlowConstraint,
 437                                                                                 allocConstraint(AND, getElementValueConstraint(elem1->element, elem1->encodingArray[i]),
 438                                                                                 getElementValueConstraint(elem2->element, elem2->encodingArray[j])));
 439                                                                 Constraint* const2 = allocConstraint(IMPLIES, allocConstraint(AND, getElementValueConstraint(elem1->element, elem1->encodingArray[i]),
 440                                                                                 getElementValueConstraint(elem2->element, elem2->encodingArray[j])), overFlowConstraint);
 441                                                                 Constraint* res [] = {const1, const2, constraint};
 442                                                                 carray[size++] = allocArrayConstraint(AND, 3, res);
 443                                                         }
 444                                                 case NOOVERFLOW:
 445                                                         if(hasOverFlow)
 446                                                                 ASSERT(0);
 447                                                                 carray[size++] = constraint;
 448                                                 default:
 449                                                         ASSERT(0);
 450                                         }
 451
 452                                 }
 453                         }
 454                 }
 455         }
 456         return allocArrayConstraint(AND, size, carray);
 457 }
 458
 459 Constraint* encodeEnumTableElemFunctionSATEncoder(SATEncoder* encoder, ElementFunction* This){
 460         ASSERT(GETFUNCTIONTYPE(This->function)==TABLEFUNC);
 461         ArrayElement* elements= &This->inputs;
 462         Table* table = ((FunctionTable*) (This->function))->table;
 463         uint size = getSizeVectorTableEntry(&table->entries);
 464         Constraint* constraints[size]; //FIXME: should add a space for the case that didn't match any entries
 465         for(uint i=0; i<size; i++){
 466                 TableEntry* entry = getVectorTableEntry(&table->entries, i);
 467                 uint inputNum =getSizeArrayElement(elements);
 468                 Constraint* carray[inputNum];
 469                 for(uint j=0; j<inputNum; j++){
 470                         Element* el= getArrayElement(elements, j);
 471                         carray[j] = getElementValueConstraint(el, entry->inputs[j]);
 472                         ASSERT(carray[j]!= NULL);
 473                 }
 474                 Constraint* output = getElementValueConstraint((Element*)This, entry->output);
 475                 ASSERT(output!= NULL);
 476                 Constraint* row= allocConstraint(IMPLIES, allocArrayConstraint(AND, inputNum, carray), output);
 477                 constraints[i]=row;
 478         }
 479         Constraint* result = allocArrayConstraint(OR, size, constraints);
 480         return result;
 481 }