bitwise_count.hpp

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#pragma once

#include <sycl/sycl.hpp>

// dpctl tensor headers
#include "utils/type_utils.hpp"

namespace dpnp::kernels::bitwise_count
{
namespace tu_ns = dpctl::tensor::type_utils;

template <typename argT, typename resT>
struct BitwiseCountFunctor
{
    // is function constant for given argT
    using is_constant = typename std::false_type;
    // constant value, if constant
    // constexpr resT constant_value = resT{};
    // is function defined for sycl::vec
    using supports_vec = typename std::false_type;
    // do both argT and resT support subgroup store/load operation
    using supports_sg_loadstore = typename std::true_type;

    resT operator()(const argT &x) const
    {
        if constexpr (std::is_unsigned_v<argT>) {
            return sycl::popcount(x);
        }
        else {
            return sycl::popcount(sycl::abs(x));
        }
    }
};
} // namespace dpnp::kernels::bitwise_count