Method MakeCache

include/xgboost/data.h:339–346

* @brief Make a copy of self for DMatrix to describe how its existing index was generated. */

   * @brief Make a copy of self for DMatrix to describe how its existing index was generated.
   */
  [[nodiscard]] BatchParam MakeCache() const {
    auto p = *this;
    // These parameters have nothing to do with how the gradient index was generated in the
    // first place.
    p.regen = false;
    p.forbid_regen = false;
    return p;
  }
};

struct HostSparsePageView {