bit_cast.hpp

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#ifndef MIGRAPHX_GUARD_RTGLIB_BITCAST_HPP
#define MIGRAPHX_GUARD_RTGLIB_BITCAST_HPP
#include <type_traits>
#if defined(__GNUC__) && !defined(__clang__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
#endif

#include <migraphx/requires.hpp>
#include <migraphx/config.hpp>

// NOLINTNEXTLINE(cppcoreguidelines-macro-usage)
#define MIGRAPHX_CONST_FOLD(x) (__builtin_constant_p(x) ? (x) : (x))

namespace migraphx {
inline namespace MIGRAPHX_INLINE_NS {
template <typename To,
          typename From,
          MIGRAPHX_REQUIRES(std::is_trivially_copyable<To>{} and
                            std::is_trivially_copyable<From>{})>
inline constexpr To bit_cast(From fr) noexcept
{
    static_assert(sizeof(To) == sizeof(From));
#if defined(__GNUC__) and !defined(__clang__)
    return MIGRAPHX_CONST_FOLD(*reinterpret_cast<To*>(&fr));
#else
    return __builtin_bit_cast(To, fr);
#endif
}
} // namespace MIGRAPHX_INLINE_NS
} // namespace migraphx
#if defined(__GNUC__) && !defined(__clang__)
#pragma GCC diagnostic pop
#endif
#endif // MIGRAPHX_GUARD_RTGLIB_BITCAST_HPP