1 | //===----------------------------------------------------------------------===// |
2 | // DuckDB |
3 | // |
4 | // duckdb/execution/index/art/swizzleable_pointer.hpp |
5 | // |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | #pragma once |
9 | |
10 | #include "duckdb/common/constants.hpp" |
11 | |
12 | namespace duckdb { |
13 | |
14 | // classes |
15 | class MetaBlockReader; |
16 | |
17 | // structs |
18 | struct BlockPointer; |
19 | |
20 | //! SwizzleablePointer provides functions on a (possibly) swizzled pointer. If the swizzle flag is set, then the |
21 | //! pointer points to a storage address (and has no type), otherwise the pointer has a type and stores |
22 | //! other information (e.g., a buffer location) |
23 | class SwizzleablePointer { |
24 | public: |
25 | //! Constructs an empty SwizzleablePointer |
26 | SwizzleablePointer() : swizzle_flag(0), type(0), offset(0), buffer_id(0) {}; |
27 | //! Constructs a swizzled pointer from a buffer ID and an offset |
28 | explicit SwizzleablePointer(MetaBlockReader &reader); |
29 | //! Constructs a non-swizzled pointer from a buffer ID and an offset |
30 | SwizzleablePointer(uint32_t offset, uint32_t buffer_id) |
31 | : swizzle_flag(0), type(0), offset(offset), buffer_id(buffer_id) {}; |
32 | |
33 | //! The swizzle flag, set if swizzled, not set otherwise |
34 | uint8_t swizzle_flag : 1; |
35 | //! The type of the pointer, zero if not set |
36 | uint8_t type : 7; |
37 | //! The offset of a memory location |
38 | uint32_t offset : 24; |
39 | //! The buffer ID of a memory location |
40 | uint32_t buffer_id : 32; |
41 | |
42 | public: |
43 | //! Checks if the pointer is swizzled |
44 | inline bool IsSwizzled() const { |
45 | return swizzle_flag; |
46 | } |
47 | //! Returns true, if neither the swizzle flag nor the type is set, and false otherwise |
48 | inline bool IsSet() const { |
49 | return swizzle_flag || type; |
50 | } |
51 | //! Reset the pointer |
52 | inline void Reset() { |
53 | swizzle_flag = 0; |
54 | type = 0; |
55 | } |
56 | }; |
57 | |
58 | } // namespace duckdb |
59 | |