QmlProfiler: Add data stream operators for QmlEvent

We try to further compress the QML events when saving as we can use the
additional space in that case.

Change-Id: Ida308963685169d1daabd7936612628fd4d265ae
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

1 files changed, 246 insertions, 0 deletions

diff --git a/src/plugins/qmlprofiler/qmlevent.cpp b/src/plugins/qmlprofiler/qmlevent.cpp
new file mode 100644
index 0000000000..4c848ef0ce
--- /dev/null
+++ b/src/plugins/qmlprofiler/qmlevent.cpp
@@ -0,0 +1,246 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "qmlevent.h"
+#include <QDataStream>
+#include <QDebug>
+
+namespace QmlProfiler {
+
+enum SerializationType {
+    OneByte    = 0,
+    TwoByte    = 1,
+    FourByte   = 2,
+    EightByte  = 3,
+    TypeMask   = 0x3
+};
+
+enum SerializationTypeOffset {
+    TimestampOffset  = 0,
+    TypeIndexOffset  = 2,
+    DataLengthOffset = 4,
+    DataOffset       = 6
+};
+
+template<typename Number>
+static void readNumbers(QDataStream &stream, Number *data, quint16 length)
+{
+    for (quint16 i = 0; i != length; ++i)
+        stream >> data[i];
+}
+
+template<typename Number>
+static Number readNumber(QDataStream &stream, qint8 type)
+{
+    switch (type) {
+    case OneByte: {
+        qint8 value;
+        stream >> value;
+        return static_cast<Number>(value);
+    }
+    case TwoByte: {
+        qint16 value;
+        stream >> value;
+        return static_cast<Number>(value);
+    }
+    case FourByte: {
+        qint32 value;
+        stream >> value;
+        return static_cast<Number>(value);
+    }
+    case EightByte: {
+        qint64 value;
+        stream >> value;
+        return static_cast<Number>(value);
+    }
+    default:
+        Q_UNREACHABLE();
+        return 0;
+    }
+}
+
+QDataStream &operator>>(QDataStream &stream, QmlEvent &event)
+{
+    qint8 type;
+    stream >> type;
+
+    event.m_timestamp = readNumber<qint64>(stream, (type >> TimestampOffset) & TypeMask);
+    event.m_typeIndex = readNumber<qint32>(stream, (type >> TypeIndexOffset) & TypeMask);
+    event.m_dataLength = readNumber<qint16>(stream, (type >> DataLengthOffset) & TypeMask);
+
+    quint8 bytesPerNumber = 1 << ((type >> DataOffset) & TypeMask);
+
+    if (event.m_dataLength * bytesPerNumber > sizeof(event.m_data)) {
+        event.m_dataType = static_cast<QmlEvent::Type>((bytesPerNumber * 8) | QmlEvent::External);
+        event.m_data.external = malloc(event.m_dataLength * bytesPerNumber);
+    } else {
+        event.m_dataType = static_cast<QmlEvent::Type>(bytesPerNumber * 8);
+    }
+
+    switch (event.m_dataType) {
+    case QmlEvent::Inline8Bit:
+        readNumbers<qint8>(stream, event.m_data.internal8bit, event.m_dataLength);
+        break;
+    case QmlEvent::External8Bit:
+        readNumbers<qint8>(stream, static_cast<qint8 *>(event.m_data.external),
+                           event.m_dataLength);
+        break;
+    case QmlEvent::Inline16Bit:
+        readNumbers<qint16>(stream, event.m_data.internal16bit, event.m_dataLength);
+        break;
+    case QmlEvent::External16Bit:
+        readNumbers<qint16>(stream, static_cast<qint16 *>(event.m_data.external),
+                            event.m_dataLength);
+        break;
+    case QmlEvent::Inline32Bit:
+        readNumbers<qint32>(stream, event.m_data.internal32bit, event.m_dataLength);
+        break;
+    case QmlEvent::External32Bit:
+        readNumbers<qint32>(stream, static_cast<qint32 *>(event.m_data.external),
+                            event.m_dataLength);
+        break;
+    case QmlEvent::Inline64Bit:
+        readNumbers<qint64>(stream, event.m_data.internal64bit, event.m_dataLength);
+        break;
+    case QmlEvent::External64Bit:
+        readNumbers<qint64>(stream, static_cast<qint64 *>(event.m_data.external),
+                            event.m_dataLength);
+        break;
+    default:
+        Q_UNREACHABLE();
+        break;
+    }
+
+    return stream;
+}
+
+static qint8 minimumType(const QmlEvent &event, quint16 length, quint16 origBitsPerNumber)
+{
+    qint8 type = OneByte;
+    bool ok = true;
+    for (quint16 i = 0; i < length;) {
+        if ((1 << type) == origBitsPerNumber / 8)
+            return type;
+        switch (type) {
+        case OneByte:
+            ok = (event.number<qint8>(i) == event.number<qint64>(i));
+            break;
+        case TwoByte:
+            ok = (event.number<qint16>(i) == event.number<qint64>(i));
+            break;
+        case FourByte:
+            ok = (event.number<qint32>(i) == event.number<qint64>(i));
+            break;
+        case EightByte:
+            ok = true;
+            break;
+        default:
+            Q_UNREACHABLE();
+            break;
+        }
+
+        if (ok)
+            ++i;
+        else
+            ++type;
+    }
+    return type;
+}
+
+template<typename Number>
+static qint8 minimumType(Number number)
+{
+     if (static_cast<qint8>(number) == number)
+         return OneByte;
+     if (static_cast<qint16>(number) == number)
+         return TwoByte;
+     if (static_cast<qint32>(number) == number)
+         return FourByte;
+     return EightByte;
+}
+
+template<typename Number>
+static void writeNumbers(QDataStream &stream, const QmlEvent &event, quint16 length)
+{
+    for (quint16 i = 0; i != length; ++i)
+        stream << event.number<Number>(i);
+}
+
+template<typename Number>
+static void writeNumber(QDataStream &stream, Number number, qint8 type)
+{
+    switch (type) {
+    case OneByte:
+        stream << static_cast<qint8>(number);
+        break;
+    case TwoByte:
+        stream << static_cast<qint16>(number);
+        break;
+    case FourByte:
+        stream << static_cast<qint32>(number);
+        break;
+    case EightByte:
+        stream << static_cast<qint64>(number);
+        break;
+    default:
+        Q_UNREACHABLE();
+        break;
+    }
+}
+
+QDataStream &operator<<(QDataStream &stream, const QmlEvent &event)
+{
+    qint8 type = minimumType(event.m_timestamp) << TimestampOffset;
+    type |= minimumType(event.m_typeIndex) << TypeIndexOffset;
+    type |= minimumType(event.m_dataLength) << DataLengthOffset;
+    type |= minimumType(event, event.m_dataLength, event.m_dataType) << DataOffset;
+    stream << type;
+
+    writeNumber(stream, event.m_timestamp, (type >> TimestampOffset) & TypeMask);
+    writeNumber(stream, event.m_typeIndex, (type >> TypeIndexOffset) & TypeMask);
+    writeNumber(stream, event.m_dataLength, (type >> DataLengthOffset) & TypeMask);
+
+    switch ((type >> DataOffset) & TypeMask) {
+    case OneByte:
+        writeNumbers<qint8>(stream, event, event.m_dataLength);
+        break;
+    case TwoByte:
+        writeNumbers<qint16>(stream, event, event.m_dataLength);
+        break;
+    case FourByte:
+        writeNumbers<qint32>(stream, event, event.m_dataLength);
+        break;
+    case EightByte:
+        writeNumbers<qint64>(stream, event, event.m_dataLength);
+        break;
+    default:
+        Q_UNREACHABLE();
+        break;
+    }
+
+    return stream;
+}
+
+} // namespace QmlProfiler