se::Stream* stream);

  // Refresh the status of streams_defined_on_. Return the first not-OK stream's
  // status or OK.
  Status RefreshStatusOfStreams();

  // Convert from a raw pointer to an XlaTensor, removing the pointer tag.
  static XlaTensor* FromOpaquePointer(void* ptr);
  // Convert to a raw pointer from an XlaTensor, adding the pointer tag.

                                     se::Stream* stream) {
  mutex_lock lock(mu_);
  definition_event_ = std::move(event);
  streams_defined_on_ = {stream};
}

Status XlaTensor::RefreshStatusOfStreams() {
  mutex_lock lock(mu_);
  Status status;
  for (se::Stream* stream : streams_defined_on_) {
    status.Update(stream->RefreshStatus());
  }
  return status;
}

        // results from a failed stream being propagated to following
        // host-side ops.
        if (!device_allows_sync_on_completion) {
          done_status.Update(xla_tensor->RefreshStatusOfStreams());
        }
        done(done_status);
        ref.Unref();
        // If a stream is in a bad state, it gets deleted when it's returned to