lcm.hpp

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#pragma once
 
#include <oneapi/dpl/numeric>
#include <sycl/sycl.hpp>
 
namespace dpnp::kernels::lcm
{
template <typename argT1, typename argT2, typename resT>
struct LcmFunctor
{
    using supports_sg_loadstore = typename std::true_type;
    using supports_vec = typename std::false_type;
 
    resT operator()(const argT1 &in1, const argT2 &in2) const
    {
        static_assert(std::is_same_v<argT1, argT2>,
                      "Input types are expected to be the same");
 
        if (in1 == 0 || in2 == 0)
            return 0;
 
        resT res = in1 / oneapi::dpl::gcd(in1, in2) * in2;
        if constexpr (std::is_signed_v<argT1>) {
            if (res < 0) {
                return -res;
            }
        }
        return res;
 
        // TODO: undo the w/a once ONEDPL-1320 is resolved
        // return oneapi::dpl::lcm(in1, in2);
    }
};
} // namespace dpnp::kernels::lcm