absl::InlinedVector<OutputTensor, 4>* ret_nodes,
    absl::InlinedVector<Node*, 4>* control_ret_nodes) {
  arg_nodes->reserve(fbody.arg_nodes.size());
  ret_nodes->reserve(fbody.ret_nodes.size());
  for (auto arg : fbody.arg_nodes) {
    arg_nodes->emplace_back(arg, 0);
  }
  for (auto ret : fbody.ret_nodes) {
    ret_nodes->emplace_back(ret, 0);
  }

  return recv_at_host_node;
}

// Gets data types from `ret_nodes` and fills them into `send_from_host_dtypes`.
Status GetRetDataTypes(const std::vector<Node*>& ret_nodes,
                       std::vector<DataType>* send_from_host_dtypes) {
  send_from_host_dtypes->resize(ret_nodes.size(), DT_INVALID);
  for (auto* n : ret_nodes) {
    int index;
    TF_RETURN_IF_ERROR(GetNodeAttr(n->attrs(), "index", &index));