TFE_Context* context_ TF_GUARDED_BY(execution_mutex_);
  const char* operation_name_ TF_GUARDED_BY(execution_mutex_);
  absl::optional<int64_t> step_id_ TF_GUARDED_BY(execution_mutex_) =
      absl::nullopt;
  std::vector<TFE_TensorHandle*> op_inputs_ TF_GUARDED_BY(execution_mutex_);
  const TFE_OpAttrs* attributes_ TF_GUARDED_BY(execution_mutex_);
  int expected_max_outputs_ TF_GUARDED_BY(execution_mutex_);