/**Function*************************************************************
Synopsis [Converts the network from SOP to BDD representation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkSopToBdd( Abc_Ntk_t * pNtk )
{
Abc_Obj_t * pNode;
DdManager * dd;
int nFaninsMax, i;
assert( Abc_NtkHasSop(pNtk) );
// start the functionality manager
nFaninsMax = Abc_NtkGetFaninMax( pNtk );
if ( nFaninsMax == 0 )
printf( "Warning: The network has only constant nodes.\n" );
dd = Cudd_Init( nFaninsMax, 0, CUDD_UNIQUE_SLOTS, CUDD_CACHE_SLOTS, 0 );
// convert each node from SOP to BDD
Abc_NtkForEachNode( pNtk, pNode, i )
{
assert( pNode->pData );
pNode->pData = Abc_ConvertSopToBdd( dd, pNode->pData );
if ( pNode->pData == NULL )
{
printf( "Abc_NtkSopToBdd: Error while converting SOP into BDD.\n" );
return 0;
}
Cudd_Ref( pNode->pData );
}
/**Function*************************************************************
Synopsis [Derive BDD of the characteristic function.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
DdNode * Abc_ResBuildBdd( Abc_Ntk_t * pNtk, DdManager * dd )
{
Vec_Ptr_t * vNodes, * vBdds, * vLocals;
Abc_Obj_t * pObj, * pFanin;
DdNode * bFunc, * bPart, * bTemp, * bVar;
int i, k;
assert( Abc_NtkIsSopLogic(pNtk) );
assert( Abc_NtkCoNum(pNtk) <= 3 );
vBdds = Vec_PtrStart( Abc_NtkObjNumMax(pNtk) );
Abc_NtkForEachCi( pNtk, pObj, i )
Vec_PtrWriteEntry( vBdds, Abc_ObjId(pObj), Cudd_bddIthVar(dd, i) );
// create internal node BDDs
vNodes = Abc_NtkDfs( pNtk, 0 );
vLocals = Vec_PtrAlloc( 6 );
Vec_PtrForEachEntry( Abc_Obj_t *, vNodes, pObj, i )
{
if ( Abc_ObjFaninNum(pObj) == 0 )
{
bFunc = Cudd_NotCond( Cudd_ReadOne(dd), Abc_SopIsConst0((char *)pObj->pData) ); Cudd_Ref( bFunc );
Vec_PtrWriteEntry( vBdds, Abc_ObjId(pObj), bFunc );
continue;
}
Vec_PtrClear( vLocals );
Abc_ObjForEachFanin( pObj, pFanin, k )
Vec_PtrPush( vLocals, Vec_PtrEntry(vBdds, Abc_ObjId(pFanin)) );
bFunc = Abc_ConvertSopToBdd( dd, (char *)pObj->pData, (DdNode **)Vec_PtrArray(vLocals) ); Cudd_Ref( bFunc );
Vec_PtrWriteEntry( vBdds, Abc_ObjId(pObj), bFunc );
}
Vec_PtrFree( vLocals );
// create char function
bFunc = Cudd_ReadOne( dd ); Cudd_Ref( bFunc );
Abc_NtkForEachCo( pNtk, pObj, i )
{
bVar = Cudd_bddIthVar( dd, i + Abc_NtkCiNum(pNtk) );
bTemp = (DdNode *)Vec_PtrEntry( vBdds, Abc_ObjFaninId0(pObj) );
bPart = Cudd_bddXnor( dd, bTemp, bVar ); Cudd_Ref( bPart );
bFunc = Cudd_bddAnd( dd, bTemp = bFunc, bPart ); Cudd_Ref( bFunc );
Cudd_RecursiveDeref( dd, bTemp );
Cudd_RecursiveDeref( dd, bPart );
}
