private void removeErroneousNodes() {
    mapSupportPoints = new HashMap<>();

    calcReachabilitySuppPoints(EdgeType.REGULAR);

    iterateReachability((node, mapSets) -> {
      Integer nodeid = node.id;

      FastFixedSet<Integer> setReachability = mapSets.get(nodeid);
      List<FastFixedSet<Integer>> lstPredSets = new ArrayList<>();

      for (StatEdge prededge : node.getPredecessorEdges(EdgeType.REGULAR)) {
        FastFixedSet<Integer> setPred = mapSets.get(prededge.getSource().id);
        if (setPred == null) {
          setPred = mapSupportPoints.get(prededge.getSource().id);
        }

        // setPred cannot be empty as it is a reachability set
        lstPredSets.add(setPred);
      }

      for (Integer id : setReachability) {

        FastFixedSet<Integer> setReachabilityCopy = setReachability.getCopy();

        FastFixedSet<Integer> setIntersection = factory.spawnEmptySet();
        boolean isIntersectionInitialized = false;

        for (FastFixedSet<Integer> predset : lstPredSets) {
          if (predset.contains(id)) {
            if (!isIntersectionInitialized) {
              setIntersection.union(predset);
              isIntersectionInitialized = true;
            }
            else {
              setIntersection.intersection(predset);
            }
          }
        }

        if (nodeid != id.intValue()) {
          setIntersection.add(nodeid);
        }
        else {
          setIntersection.remove(nodeid);
        }

        setReachabilityCopy.complement(setIntersection);

        mapExtPostdominators.get(id).complement(setReachabilityCopy);
      }

      return false;
    }, EdgeType.REGULAR);

    // exception handlers cannot be postdominator nodes
    // TODO: replace with a standard set?
    FastFixedSet<Integer> setHandlers = factory.spawnEmptySet();
    boolean handlerfound = false;

    for (Statement stat : statement.getStats()) {
      if (stat.getPredecessorEdges(EdgeType.DIRECT_ALL).isEmpty() &&
          !stat.getPredecessorEdges(EdgeType.EXCEPTION).isEmpty()) { // exception handler
        setHandlers.add(stat.id);
        handlerfound = true;
      }
    }

    if (handlerfound) {
      for (FastFixedSet<Integer> set : mapExtPostdominators.values()) {
        set.complement(setHandlers);
      }
    }
  }
private void removeErroneousNodes()