Method get_used_time

lite/src/misc.h:187–192

    Timer(std::string name) : m_name(name) { m_start = Clock::now(); }
    double get_used_time() {
        m_stop = Clock::now();
        std::chrono::duration<double> elapsed = m_stop - m_start;
        Nsec u = std::chrono::duration_cast<Nsec>(elapsed);
        return static_cast<double>(u.count()) / 1000000.0;
    }
    void print_used_time(int iter) {
        m_stop = Clock::now();
        std::chrono::duration<double> elapsed = m_stop - m_start;