final Node<V>[] helpTransfer(Node<V>[] tab, Node<V> f) {
      Node<V>[] nextTab; int sc;
      if (tab != null && (f instanceof ForwardingNode) &&
          (nextTab = ((ForwardingNode<V>)f).nextTable) != null) {
          int rs = resizeStamp(tab.length) << RESIZE_STAMP_SHIFT;
          while (nextTab == nextTable && table == tab &&
                 (sc = sizeCtl) < 0) {
              if (sc == rs + MAX_RESIZERS || sc == rs + 1 ||
                  transferIndex <= 0)
                  break;
              if (SIZECTL.compareAndSet(this, sc, sc + 1)) {
                  transfer(tab, nextTab);
                  break;
              }
          }
          return nextTab;
      }
      return table;
  }
final Node<V>[] helpTransfer(Node<V>[] tab, Node<V> f)