debug_timer

static const bool use_debug_timer = true;
static quint32 last_id = 0;
static qint64 warning_maximum = 1000;

struct DebugTimer {
    DebugTimer(const QString& func_name, bool use_debug_timer, quint32& last_id) {
        if (use_debug_timer) {
            id = last_id + 1;
            last_id = id;
            this->func_name = func_name;
            used = true;
            timer.start();
        }
    }
    void end(qint64 warning_minimum) {
        if (used) {
            qint64 elapsed = timer.elapsed();
            if (elapsed > warning_minimum) {
                qDebug() << func_name << " [" << id << "] took " << timer.elapsed() << " msecs!";
            }
        }
    }
    QElapsedTimer timer;
    quint32 id;
    QString func_name;
    bool used = false;
};

void f() {
    DebugTimer debug_timer(__func__, use_debug_timer, last_id);
    do_stuff();
    debug_timer.end(warning_maximum);
}

qint32 b() {
    DebugTimer debug_timer(__func__, use_debug_timer, last_id);
    if (sth1 && sth2 && sth3) {
        debug_timer.end(warning_maximum);
        return 1;
    }
    else if (sth1 && (sth2 || sth3)) {
        debug_timer.end(warning_maximum);
        return 2;
    }
    debug_timer.end(warning_maximum);
    return 3;
}