private void buildGraph(PsiReference[] refs) {
    myMarkedNodes.clear();
    myExpressionsQueue = new ArrayDeque<>(refs.length);
    myElementToNode.clear();
    for (PsiReference ref : refs) {
      processUsage(ref.getElement());
    }

    processQueue();

    markNodes();

    spreadMarks();
  }
private void buildGraph(PsiReference[] refs)