qt5base-lts/tests/auto/testlib/selftests/benchlibtickcounter/tst_benchlibtickcounter.cpp

/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the test suite of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/


#include <QtCore/QCoreApplication>
#include <QtTest/QtTest>

#include <private/cycle_p.h>

class tst_BenchlibTickCounter: public QObject
{
    Q_OBJECT

private slots:
    void threeBillionTicks();
};

void tst_BenchlibTickCounter::threeBillionTicks()
{
#ifndef HAVE_TICK_COUNTER
    QSKIP("Tick counter not available on this platform");
#else
    QBENCHMARK {
        CycleCounterTicks start = getticks();
        double el = 0.;
        double max = el;
        while (el < 3000000000.) {
            /* Verify that elapsed time never decreases */
            QVERIFY2(el >= max, qPrintable(
                QString("Tick counter is not monotonic\nElapsed moved from %1 to %2")
                    .arg(max).arg(el)
            ));
            max = el;
            el = elapsed(getticks(), start);
        }
    }
#endif
}

QTEST_MAIN(tst_BenchlibTickCounter)

#include "tst_benchlibtickcounter.moc"