1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
/**
* Copyright 2017-2023 by XGBoost Contributors
*/
#ifndef XGBOOST_DATA_ELLPACK_PAGE_H_
#define XGBOOST_DATA_ELLPACK_PAGE_H_
#include <memory> // for unique_ptr
#include "../common/hist_util.h" // for HistogramCuts
#include "xgboost/context.h" // for Context
#include "xgboost/data.h" // for DMatrix, BatchParam
namespace xgboost {
class EllpackPageImpl;
/**
* @brief A page stored in ELLPACK format.
*
* This class uses the PImpl idiom (https://en.cppreference.com/w/cpp/language/pimpl) to avoid
* including CUDA-specific implementation details in the header.
*
* See @ref EllpackPageImpl .
*/
class EllpackPage {
public:
/**
* @brief Default constructor.
*
* This is used in the external memory case. An empty ELLPACK page is constructed with its content
* set later by the reader.
*/
EllpackPage();
/**
* @brief Constructor from an existing DMatrix.
*
* This is used in the in-memory case. The ELLPACK page is constructed from an existing DMatrix
* in CSR format.
*/
explicit EllpackPage(Context const* ctx, DMatrix* dmat, const BatchParam& param);
~EllpackPage() noexcept(false);
EllpackPage(EllpackPage&& that);
/*! \return Number of instances in the page. */
[[nodiscard]] bst_idx_t Size() const;
/*! \brief Set the base row id for this page. */
void SetBaseRowId(std::size_t row_id);
[[nodiscard]] const EllpackPageImpl* Impl() const { return impl_.get(); }
EllpackPageImpl* Impl() { return impl_.get(); }
[[nodiscard]] common::HistogramCuts const& Cuts() const;
[[nodiscard]] bst_idx_t BaseRowId() const;
private:
std::unique_ptr<EllpackPageImpl> impl_;
};
} // namespace xgboost
#endif // XGBOOST_DATA_ELLPACK_PAGE_H_