1 | #include <Functions/FunctionFactory.h> |
2 | #include <Functions/FunctionBinaryArithmetic.h> |
3 | #include <Core/AccurateComparison.h> |
4 | |
5 | namespace DB |
6 | { |
7 | |
8 | template <typename A, typename B> |
9 | struct LeastBaseImpl |
10 | { |
11 | using ResultType = NumberTraits::ResultOfLeast<A, B>; |
12 | |
13 | template <typename Result = ResultType> |
14 | static inline Result apply(A a, B b) |
15 | { |
16 | /** gcc 4.9.2 successfully vectorizes a loop from this function. */ |
17 | return static_cast<Result>(a) < static_cast<Result>(b) ? static_cast<Result>(a) : static_cast<Result>(b); |
18 | } |
19 | |
20 | #if USE_EMBEDDED_COMPILER |
21 | static constexpr bool compilable = true; |
22 | |
23 | static inline llvm::Value * compile(llvm::IRBuilder<> & b, llvm::Value * left, llvm::Value * right, bool is_signed) |
24 | { |
25 | if (!left->getType()->isIntegerTy()) |
26 | /// XXX minnum is basically fmin(), it may or may not match whatever apply() does |
27 | return b.CreateMinNum(left, right); |
28 | return b.CreateSelect(is_signed ? b.CreateICmpSLT(left, right) : b.CreateICmpULT(left, right), left, right); |
29 | } |
30 | #endif |
31 | }; |
32 | |
33 | template <typename A, typename B> |
34 | struct LeastSpecialImpl |
35 | { |
36 | using ResultType = std::make_signed_t<A>; |
37 | |
38 | template <typename Result = ResultType> |
39 | static inline Result apply(A a, B b) |
40 | { |
41 | static_assert(std::is_same_v<Result, ResultType>, "ResultType != Result" ); |
42 | return accurate::lessOp(a, b) ? static_cast<Result>(a) : static_cast<Result>(b); |
43 | } |
44 | |
45 | #if USE_EMBEDDED_COMPILER |
46 | static constexpr bool compilable = false; /// ??? |
47 | #endif |
48 | }; |
49 | |
50 | template <typename A, typename B> |
51 | using LeastImpl = std::conditional_t<!NumberTraits::LeastGreatestSpecialCase<A, B>, LeastBaseImpl<A, B>, LeastSpecialImpl<A, B>>; |
52 | |
53 | struct NameLeast { static constexpr auto name = "least" ; }; |
54 | using FunctionLeast = FunctionBinaryArithmetic<LeastImpl, NameLeast>; |
55 | |
56 | void registerFunctionLeast(FunctionFactory & factory) |
57 | { |
58 | factory.registerFunction<FunctionLeast>(); |
59 | } |
60 | |
61 | } |
62 | |