Function ByteSwap

12.08-byteSwap1/main.cpp:30–49

template<std::integral T>
constexpr T ByteSwap(T value)
{
  if constexpr(std::endian::native == std::endian::big ||
               (sizeof(value) == 1)) {
    return value;
  } else {
    if(std::is_constant_evaluated()) {
      return ReverseBytes(value);
    } else {
      if constexpr(std::same_as<T, uint64_t>) {
        return htonl(value >> 32) |
               (static_cast<uint64_t>(htonl(value)) << 32);
      } else if constexpr(std::same_as<T, uint32_t>) {
        return htonl(value);
      } else if constexpr(std::same_as<T, uint16_t>) {
        return htons(value);
      }
    }
  }
}

static_assert(ByteSwap(uint64_t(0x123456789ABCDEF0)) ==
              0xF0DEBC9A78563412);