send_device.size());
  TFE_OpSetAttrString(op, "recv_device", recv_device.c_str(),
                      recv_device.size());
  TFE_OpSetAttrInt(op, "send_device_incarnation", send_device_incarnation);

  return op;
}

TFE_Op* RecvOp(TFE_Context* ctx, const std::string& op_name,
               const std::string& send_device, const std::string& recv_device,
               tensorflow::uint64 send_device_incarnation) {

  // CHECK: tf_mlrt.await [[result_future]]
  %0 = "tf.Recv"() {__op_key = 0: i32, device = "/device:CPU:0", tensor_name = "tensor", send_device = "/device:CPU:0", send_device_incarnation = 0, recv_device = "/device:CPU:0"} : () -> tensor<f32>