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
   7 SATEncoder * allocSATEncoder() {
   8         SATEncoder *This=ourmalloc(sizeof (SATEncoder));
   9         This->varcount=1;
  10         return This;
  11 }
  12
  13 void deleteSATEncoder(SATEncoder *This) {
  14         ourfree(This);
  15 }
  16
  17 void encodeAllSATEncoder(SATEncoder * This, CSolver *csolver) {
  18         VectorBoolean *constraints=csolver->constraints;
  19         uint size=getSizeVectorBoolean(constraints);
  20         for(uint i=0;i<size;i++) {
  21                 Boolean *constraint=getVectorBoolean(constraints, i);
  22                 encodeConstraintSATEncoder(This, constraint);
  23         }
  24 }
  25
  26 Constraint * encodeConstraintSATEncoder(SATEncoder *This, Boolean *constraint) {
  27         switch(constraint->btype) {
  28         case ORDERCONST:
  29                 return encodeOrderSATEncoder(This, (BooleanOrder *) constraint);
  30         case BOOLEANVAR:
  31                 return encodeVarSATEncoder(This, (BooleanVar *) constraint);
  32         case LOGICOP:
  33                 return encodeLogicSATEncoder(This, (BooleanLogic *) constraint);
  34         }
  35 }
  36
  37 Constraint * encodeOrderSATEncoder(SATEncoder *This, BooleanOrder * constraint) {
  38         return NULL;
  39 }
  40
  41 Constraint * getNewVarSATEncoder(SATEncoder *This) {
  42         Constraint * var=allocVarConstraint(VAR, This->varcount);
  43         Constraint * varneg=allocVarConstraint(NOTVAR, This->varcount++);
  44         setNegConstraint(var, varneg);
  45         setNegConstraint(varneg, var);
  46         return var;
  47 }
  48
  49 Constraint * encodeVarSATEncoder(SATEncoder *This, BooleanVar * constraint) {
  50         if (constraint->var == NULL) {
  51                 constraint->var=getNewVarSATEncoder(This);
  52         }
  53         return constraint->var;
  54 }
  55
  56 Constraint * encodeLogicSATEncoder(SATEncoder *This, BooleanLogic * constraint) {
  57         Constraint *left=encodeConstraintSATEncoder(This, constraint->left);
  58         Constraint *right=NULL;
  59         if (constraint->right!=NULL)
  60                 right=encodeConstraintSATEncoder(This, constraint->right);
  61         switch(constraint->op) {
  62         case L_AND:
  63                 return allocConstraint(AND, left, right);
  64         case L_OR:
  65                 return allocConstraint(OR, left, right);
  66         case L_NOT:
  67                 return negateConstraint(allocConstraint(OR, left, NULL));
  68         case L_XOR: {
  69                 Constraint * nleft=negateConstraint(cloneConstraint(left));
  70                 Constraint * nright=negateConstraint(cloneConstraint(right));
  71                 return allocConstraint(OR,
  72                                                                                                          allocConstraint(AND, left, nright),
  73                                                                                                          allocConstraint(AND, nleft, right));
  74         }
  75         case L_IMPLIES:
  76                 return allocConstraint(IMPLIES, left, right);
  77         }
  78         return NULL;
  79 }