src/aig/kit/kitBdd.c

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#include "kit.h"
#include "extra.h"



DdNode * Kit_SopToBdd( DdManager * dd, Kit_Sop_t * cSop, int nVars )
{
    DdNode * bSum, * bCube, * bTemp, * bVar;
    unsigned uCube;
    int Value, i, v;
    assert( nVars < 16 );
    // start the cover
    bSum = Cudd_ReadLogicZero(dd);   Cudd_Ref( bSum );
   // check the logic function of the node
    Kit_SopForEachCube( cSop, uCube, i )
    {
        bCube = Cudd_ReadOne(dd);   Cudd_Ref( bCube );
        for ( v = 0; v < nVars; v++ )
        {
            Value = ((uCube >> 2*v) & 3);
            if ( Value == 1 )
                bVar = Cudd_Not( Cudd_bddIthVar( dd, v ) );
            else if ( Value == 2 )
                bVar = Cudd_bddIthVar( dd, v );
            else
                continue;
            bCube  = Cudd_bddAnd( dd, bTemp = bCube, bVar );   Cudd_Ref( bCube );
            Cudd_RecursiveDeref( dd, bTemp );
        }
        bSum = Cudd_bddOr( dd, bTemp = bSum, bCube );   
        Cudd_Ref( bSum );
        Cudd_RecursiveDeref( dd, bTemp );
        Cudd_RecursiveDeref( dd, bCube );
    }
    // complement the result if necessary
    Cudd_Deref( bSum );
    return bSum;
}

DdNode * Kit_GraphToBdd( DdManager * dd, Kit_Graph_t * pGraph )
{
    DdNode * bFunc, * bFunc0, * bFunc1;
    Kit_Node_t * pNode;
    int i;

    // sanity checks
    assert( Kit_GraphLeaveNum(pGraph) >= 0 );
    assert( Kit_GraphLeaveNum(pGraph) <= pGraph->nSize );

    // check for constant function
    if ( Kit_GraphIsConst(pGraph) )
        return Cudd_NotCond( b1, Kit_GraphIsComplement(pGraph) );
    // check for a literal
    if ( Kit_GraphIsVar(pGraph) )
        return Cudd_NotCond( Cudd_bddIthVar(dd, Kit_GraphVarInt(pGraph)), Kit_GraphIsComplement(pGraph) );

    // assign the elementary variables
    Kit_GraphForEachLeaf( pGraph, pNode, i )
        pNode->pFunc = Cudd_bddIthVar( dd, i );

    // compute the function for each internal node
    Kit_GraphForEachNode( pGraph, pNode, i )
    {
        bFunc0 = Cudd_NotCond( Kit_GraphNode(pGraph, pNode->eEdge0.Node)->pFunc, pNode->eEdge0.fCompl ); 
        bFunc1 = Cudd_NotCond( Kit_GraphNode(pGraph, pNode->eEdge1.Node)->pFunc, pNode->eEdge1.fCompl ); 
        pNode->pFunc = Cudd_bddAnd( dd, bFunc0, bFunc1 );   Cudd_Ref( pNode->pFunc );
    }

    // deref the intermediate results
    bFunc = pNode->pFunc;   Cudd_Ref( bFunc );
    Kit_GraphForEachNode( pGraph, pNode, i )
        Cudd_RecursiveDeref( dd, pNode->pFunc );
    Cudd_Deref( bFunc );

    // complement the result if necessary
    return Cudd_NotCond( bFunc, Kit_GraphIsComplement(pGraph) );
}

DdNode * Kit_TruthToBdd_rec( DdManager * dd, unsigned * pTruth, int iBit, int nVars, int nVarsTotal, int fMSBonTop )
{
    DdNode * bF0, * bF1, * bF;
    int Var;
    if ( nVars <= 5 )
    {
        unsigned uTruth, uMask;
        uMask = ((~(unsigned)0) >> (32 - (1<<nVars)));
        uTruth = (pTruth[iBit>>5] >> (iBit&31)) & uMask;
        if ( uTruth == 0 )
            return b0;
        if ( uTruth == uMask )
            return b1;        
    }
    // find the variable to use
    Var = fMSBonTop? nVarsTotal-nVars : nVars-1;
    // other special cases can be added
    bF0 = Kit_TruthToBdd_rec( dd, pTruth, iBit,                nVars-1, nVarsTotal, fMSBonTop );  Cudd_Ref( bF0 );
    bF1 = Kit_TruthToBdd_rec( dd, pTruth, iBit+(1<<(nVars-1)), nVars-1, nVarsTotal, fMSBonTop );  Cudd_Ref( bF1 );
    bF  = Cudd_bddIte( dd, dd->vars[Var], bF1, bF0 );                     Cudd_Ref( bF );
    Cudd_RecursiveDeref( dd, bF0 );
    Cudd_RecursiveDeref( dd, bF1 );
    Cudd_Deref( bF );
    return bF;
}

DdNode * Kit_TruthToBdd( DdManager * dd, unsigned * pTruth, int nVars, int fMSBonTop )
{
    return Kit_TruthToBdd_rec( dd, pTruth, 0, nVars, nVars, fMSBonTop );
}

int Kit_SopFactorVerify( Vec_Int_t * vCover, Kit_Graph_t * pFForm, int nVars )
{
    static DdManager * dd = NULL;
    Kit_Sop_t Sop, * cSop = &Sop;
    DdNode * bFunc1, * bFunc2;
    Vec_Int_t * vMemory;
    int RetValue;
    // get the manager
    if ( dd == NULL )
        dd = Cudd_Init( 16, 0, CUDD_UNIQUE_SLOTS, CUDD_CACHE_SLOTS, 0 );
    // derive SOP
    vMemory = Vec_IntAlloc( Vec_IntSize(vCover) );
    Kit_SopCreate( cSop, vCover, nVars, vMemory );
    // get the functions
    bFunc1 = Kit_SopToBdd( dd, cSop, nVars );      Cudd_Ref( bFunc1 );
    bFunc2 = Kit_GraphToBdd( dd, pFForm );         Cudd_Ref( bFunc2 );
//Extra_bddPrint( dd, bFunc1 ); printf("\n");
//Extra_bddPrint( dd, bFunc2 ); printf("\n");
    RetValue = (bFunc1 == bFunc2);
    if ( bFunc1 != bFunc2 )
    {
        int s;
        Extra_bddPrint( dd, bFunc1 ); printf("\n");
        Extra_bddPrint( dd, bFunc2 ); printf("\n");
        s  = 0;
    }
    Cudd_RecursiveDeref( dd, bFunc1 );
    Cudd_RecursiveDeref( dd, bFunc2 );
    Vec_IntFree( vMemory );
    return RetValue;
}

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