text: #include <Functions/FunctionFactory.h>
  #include <Functions/FunctionBinaryArithmetic.h>
  
  #if defined(__SSE2__)
  #    define LIBDIVIDE_SSE2 1
  #endif
  
  #include <libdivide.h>
  
  
  namespace DB
  {
  namespace ErrorCodes
  {
      extern const int ILLEGAL_DIVISION;
  }
  
  /// Optimizations for integer division by a constant.
  
  template <typename A, typename B>
  struct DivideIntegralByConstantImpl
      : BinaryOperationImplBase<A, B, DivideIntegralImpl<A, B>>
  {
      using ResultType = typename DivideIntegralImpl<A, B>::ResultType;
      static const constexpr bool allow_fixed_string = false;
  
      static NO_INLINE void vectorConstant(const A * __restrict a_pos, B b, ResultType * __restrict c_pos, size_t size)
      {
          if (unlikely(b == 0))
              throw Exception("Division by zero", ErrorCodes::ILLEGAL_DIVISION);
  
  #pragma GCC diagnostic push
  #pragma GCC diagnostic ignored "-Wsign-compare"
  
          if (unlikely(is_signed_v<B> && b == -1))
          {
              for (size_t i = 0; i < size; ++i)
                  c_pos[i] = -a_pos[i];
              return;
          }
  
  #pragma GCC diagnostic pop
  
          libdivide::divider<A> divider(b);
  
          const A * a_end = a_pos + size;
  
  #if defined(__SSE2__)
          static constexpr size_t values_per_sse_register = 16 / sizeof(A);
          const A * a_end_sse = a_pos + size / values_per_sse_register * values_per_sse_register;
  
          while (a_pos < a_end_sse)
          {
              _mm_storeu_si128(reinterpret_cast<__m128i *>(c_pos),
                  _mm_loadu_si128(reinterpret_cast<const __m128i *>(a_pos)) / divider);
  
              a_pos += values_per_sse_register;
              c_pos += values_per_sse_register;
          }
  #endif
  
          while (a_pos < a_end)
          {
              *c_pos = *a_pos / divider;
              ++a_pos;
              ++c_pos;
          }
      }
  };
  
  /** Specializations are specified for dividing numbers of the type UInt64 and UInt32 by the numbers of the same sign.
    * Can be expanded to all possible combinations, but more code is needed.
    */
  
  template <> struct BinaryOperationImpl<UInt64, UInt8, DivideIntegralImpl<UInt64, UInt8>> : DivideIntegralByConstantImpl<UInt64, UInt8> {};
  template <> struct BinaryOperationImpl<UInt64, UInt16, DivideIntegralImpl<UInt64, UInt16>> : DivideIntegralByConstantImpl<UInt64, UInt16> {};
  template <> struct BinaryOperationImpl<UInt64, UInt32, DivideIntegralImpl<UInt64, UInt32>> : DivideIntegralByConstantImpl<UInt64, UInt32> {};
  template <> struct BinaryOperationImpl<UInt64, UInt64, DivideIntegralImpl<UInt64, UInt64>> : DivideIntegralByConstantImpl<UInt64, UInt64> {};
  
  template <> struct BinaryOperationImpl<UInt32, UInt8, DivideIntegralImpl<UInt32, UInt8>> : DivideIntegralByConstantImpl<UInt32, UInt8> {};
  template <> struct BinaryOperationImpl<UInt32, UInt16, DivideIntegralImpl<UInt32, UInt16>> : DivideIntegralByConstantImpl<UInt32, UInt16> {};
  template <> struct BinaryOperationImpl<UInt32, UInt32, DivideIntegralImpl<UInt32, UInt32>> : DivideIntegralByConstantImpl<UInt32, UInt32> {};
  template <> struct BinaryOperationImpl<UInt32, UInt64, DivideIntegralImpl<UInt32, UInt64>> : DivideIntegralByConstantImpl<UInt32, UInt64> {};
  
  template <> struct BinaryOperationImpl<Int64, Int8, DivideIntegralImpl<Int64, Int8>> : DivideIntegralByConstantImpl<Int64, Int8> {};
  template <> struct BinaryOperationImpl<Int64, Int16, DivideIntegralImpl<Int64, Int16>> : DivideIntegralByConstantImpl<Int64, Int16> {};
  template <> struct BinaryOperationImpl<Int64, Int32, DivideIntegralImpl<Int64, Int32>> : DivideIntegralByConstantImpl<Int64, Int32> {};
  template <> struct BinaryOperationImpl<Int64, Int64, DivideIntegralImpl<Int64, Int64>> : DivideIntegralByConstantImpl<Int64, Int64> {};
  
  template <> struct BinaryOperationImpl<Int32, Int8, DivideIntegralImpl<Int32, Int8>> : DivideIntegralByConstantImpl<Int32, Int8> {};
  template <> struct BinaryOperationImpl<Int32, Int16, DivideIntegralImpl<Int32, Int16>> : DivideIntegralByConstantImpl<Int32, Int16> {};
  template <> struct BinaryOperationImpl<Int32, Int32, DivideIntegralImpl<Int32, Int32>> : DivideIntegralByConstantImpl<Int32, Int32> {};
  template <> struct BinaryOperationImpl<Int32, Int64, DivideIntegralImpl<Int32, Int64>> : DivideIntegralByConstantImpl<Int32, Int64> {};
  
  
  struct NameIntDiv { static constexpr auto name = "intDiv"; };
  using FunctionIntDiv = FunctionBinaryArithmetic<DivideIntegralImpl, NameIntDiv, false>;
  
  void registerFunctionIntDiv(FunctionFactory & factory)
  {
      factory.registerFunction<FunctionIntDiv>();
  }
  
  }
  