1 | #include <Functions/FunctionFactory.h> |
---|---|
2 | #include <Functions/FunctionUnaryArithmetic.h> |
3 | #include <DataTypes/NumberTraits.h> |
4 | |
5 | namespace DB |
6 | { |
7 | namespace ErrorCodes |
8 | { |
9 | extern const int BAD_CAST; |
10 | } |
11 | |
12 | /// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h). |
13 | /// This function wraps bool atomic functions |
14 | /// and transforms their boolean return value to the BoolMask ("can be false" and "can be true" bits). |
15 | template <typename A> |
16 | struct BitWrapperFuncImpl |
17 | { |
18 | using ResultType = UInt8; |
19 | |
20 | static inline ResultType NO_SANITIZE_UNDEFINED apply(A a) |
21 | { |
22 | if constexpr (!is_integral_v<A>) |
23 | throw DB::Exception("It's a bug! Only integer types are supported by __bitWrapperFunc.", ErrorCodes::BAD_CAST); |
24 | return a == 0 ? static_cast<ResultType>(0b10) : static_cast<ResultType >(0b1); |
25 | } |
26 | |
27 | #if USE_EMBEDDED_COMPILER |
28 | static constexpr bool compilable = false; |
29 | |
30 | #endif |
31 | }; |
32 | |
33 | struct NameBitWrapperFunc { static constexpr auto name = "__bitWrapperFunc"; }; |
34 | using FunctionBitWrapperFunc = FunctionUnaryArithmetic<BitWrapperFuncImpl, NameBitWrapperFunc, true>; |
35 | |
36 | template <> struct FunctionUnaryArithmeticMonotonicity<NameBitWrapperFunc> |
37 | { |
38 | static bool has() { return false; } |
39 | static IFunction::Monotonicity get(const Field &, const Field &) |
40 | { |
41 | return {}; |
42 | } |
43 | }; |
44 | |
45 | void registerFunctionBitWrapperFunc(FunctionFactory & factory) |
46 | { |
47 | factory.registerFunction<FunctionBitWrapperFunc>(); |
48 | } |
49 | |
50 | } |
51 |