ClickHouse/src/Functions/moduloOrZero.cpp
2020-09-13 21:55:12 +08:00

49 lines
1.3 KiB
C++

#include <Functions/FunctionFactory.h>
#include <Functions/FunctionBinaryArithmetic.h>
namespace DB
{
namespace
{
template <typename A, typename B>
struct ModuloOrZeroImpl
{
using ResultType = typename NumberTraits::ResultOfModulo<A, B>::Type;
static const constexpr bool allow_fixed_string = false;
template <typename Result = ResultType>
static inline Result apply(A a, B b)
{
if constexpr (std::is_floating_point_v<ResultType>)
{
/// This computation is similar to `fmod` but the latter is not inlined and has 40 times worse performance.
return ResultType(a) - trunc(ResultType(a) / ResultType(b)) * ResultType(b);
}
else
{
if (unlikely(divisionLeadsToFPE(a, b)))
return 0;
return ModuloImpl<A, B>::template apply<Result>(a, b);
}
}
#if USE_EMBEDDED_COMPILER
static constexpr bool compilable = false; /// TODO implement the checks
#endif
};
struct NameModuloOrZero { static constexpr auto name = "moduloOrZero"; };
using FunctionModuloOrZero = BinaryArithmeticOverloadResolver<ModuloOrZeroImpl, NameModuloOrZero>;
}
void registerFunctionModuloOrZero(FunctionFactory & factory)
{
factory.registerFunction<FunctionModuloOrZero>();
}
}