ClickHouse

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#include <Functions/FunctionNumericPredicate.h>
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#include <Functions/FunctionFactory.h>
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#include <type_traits>
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namespace DB
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{
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namespace
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{
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struct IsFiniteImpl
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{
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    /// Better implementation, because isinf, isfinite, isnan are not inlined for unknown reason.
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    /// Assuming IEEE 754.
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    /// NOTE gcc 7 doesn't vectorize this loop.
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    static constexpr auto name = "isFinite";
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    template <typename T>
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    static bool execute(const T t)
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    {
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        if constexpr (std::is_same_v<T, float>)
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            return (std::bit_cast<uint32_t>(t)
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                 & 0b01111111100000000000000000000000)
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                != 0b01111111100000000000000000000000;
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        else if constexpr (std::is_same_v<T, double>)
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            return (std::bit_cast<uint64_t>(t)
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                 & 0b0111111111110000000000000000000000000000000000000000000000000000)
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                != 0b0111111111110000000000000000000000000000000000000000000000000000;
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        else
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        {
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            (void)t;
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            return true;
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        }
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    }
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};
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using FunctionIsFinite = FunctionNumericPredicate<IsFiniteImpl>;
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}
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REGISTER_FUNCTION(IsFinite)
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{
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    factory.registerFunction<FunctionIsFinite>();
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}
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}
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