Suggested fix to not collect leaves of black boxes.

src/aig/gia/giaMfs.c

@@ -161,13 +161,13 @@ Sfm_Ntk_t * Gia_ManExtractMfs( Gia_Man_t * p )
         {
             nBoxIns = Tim_ManBoxInputNum( pManTime, k );
             nBoxOuts = Tim_ManBoxOutputNum( pManTime, k );
+            // iterate through box outputs
+            if ( !Tim_ManBoxIsBlack(pManTime, k) ) //&& Tim_ManBoxInputNum(pManTime, k) <= 6 )
+            {
                 // collect truth table leaves
                 Vec_IntClear( vLeaves );
                 for ( i = 0; i < nBoxIns; i++ )
                     Vec_IntPush( vLeaves, Gia_ObjId(p->pAigExtra, Gia_ManCi(p->pAigExtra, i)) );
-            // iterate through box outputs
-            if ( !Tim_ManBoxIsBlack(pManTime, k) ) //&& Tim_ManBoxInputNum(pManTime, k) <= 6 )
-            {
                 for ( j = 0; j < nBoxOuts; j++ )
                 {
                     // CI corresponding to the box outputs