Support serializing the QShader for qsb version

Support serializing shaders with specific qsb version. The default
behavior remains the same, using the latest version.

Task-number: QTBUG-101062
Pick-to: 6.5
Change-Id: I090a88c1ccb3be4ac5eee1da4058afaa8bf3111c
Reviewed-by: Laszlo Agocs <[email protected]>

7 files changed, 76 insertions, 47 deletions

diff --git a/src/gui/rhi/qshader.cpp b/src/gui/rhi/qshader.cpp
index 440e7fedc8e..c35445f7b89 100644
--- a/src/gui/rhi/qshader.cpp
+++ b/src/gui/rhi/qshader.cpp
@@ -365,9 +365,12 @@ static void writeShaderKey(QDataStream *ds, const QShaderKey &k)
     \return a serialized binary version of all the data held by the
     QShader, suitable for writing to files or other I/O devices.
 
+    By default the latest serialization format is used. Use \a version
+    parameter to serialize for a compatibility Qt version.
+
     \sa fromSerialized()
  */
-QByteArray QShader::serialized() const
+QByteArray QShader::serialized(SerializedFormatVersion version) const
 {
     static QShaderPrivate sd;
     QShaderPrivate *dd = d ? d : &sd;
@@ -378,9 +381,11 @@ QByteArray QShader::serialized() const
     if (!buf.open(QIODevice::WriteOnly))
         return QByteArray();
 
-    ds << QShaderPrivate::QSB_VERSION;
+    const int qsbVersion = QShaderPrivate::qtQsbVersion(version);
+    ds << qsbVersion;
+
     ds << int(dd->stage);
-    dd->desc.serialize(&ds);
+    dd->desc.serialize(&ds, qsbVersion);
     ds << int(dd->shaders.size());
     for (auto it = dd->shaders.cbegin(), itEnd = dd->shaders.cend(); it != itEnd; ++it) {
         const QShaderKey &k(it.key());
@@ -413,17 +418,19 @@ QByteArray QShader::serialized() const
             ds << listIt->samplerBinding;
         }
     }
-    ds << int(dd->nativeShaderInfoMap.size());
-    for (auto it = dd->nativeShaderInfoMap.cbegin(), itEnd = dd->nativeShaderInfoMap.cend(); it != itEnd; ++it) {
-        const QShaderKey &k(it.key());
-        writeShaderKey(&ds, k);
-        ds << it->flags;
-        ds << int(it->extraBufferBindings.size());
-        for (auto mapIt = it->extraBufferBindings.cbegin(), mapItEnd = it->extraBufferBindings.cend();
-             mapIt != mapItEnd; ++mapIt)
-        {
-            ds << mapIt.key();
-            ds << mapIt.value();
+    if (qsbVersion > QShaderPrivate::QSB_VERSION_WITHOUT_NATIVE_SHADER_INFO) {
+        ds << int(dd->nativeShaderInfoMap.size());
+        for (auto it = dd->nativeShaderInfoMap.cbegin(), itEnd = dd->nativeShaderInfoMap.cend(); it != itEnd; ++it) {
+            const QShaderKey &k(it.key());
+            writeShaderKey(&ds, k);
+            ds << it->flags;
+            ds << int(it->extraBufferBindings.size());
+            for (auto mapIt = it->extraBufferBindings.cbegin(), mapItEnd = it->extraBufferBindings.cend();
+                 mapIt != mapItEnd; ++mapIt)
+            {
+                ds << mapIt.key();
+                ds << mapIt.value();
+            }
         }
     }
 
diff --git a/src/gui/rhi/qshader_p.h b/src/gui/rhi/qshader_p.h
index 33c026f7796..f85b075a83b 100644
--- a/src/gui/rhi/qshader_p.h
+++ b/src/gui/rhi/qshader_p.h
@@ -110,6 +110,12 @@ public:
         NonIndexedVertexAsComputeShader
     };
 
+    enum class SerializedFormatVersion {
+        Latest = 0,
+        Qt_6_5,
+        Qt_6_4
+    };
+
     QShader();
     QShader(const QShader &other);
     QShader &operator=(const QShader &other);
@@ -129,7 +135,7 @@ public:
     void setShader(const QShaderKey &key, const QShaderCode &shader);
     void removeShader(const QShaderKey &key);
 
-    QByteArray serialized() const;
+    QByteArray serialized(SerializedFormatVersion version = SerializedFormatVersion::Latest) const;
     static QShader fromSerialized(const QByteArray &data);
 
     using NativeResourceBindingMap = QMap<int, QPair<int, int> >; // binding -> native_binding[, native_binding]
diff --git a/src/gui/rhi/qshader_p_p.h b/src/gui/rhi/qshader_p_p.h
index b0ba04ef513..58fb2072c92 100644
--- a/src/gui/rhi/qshader_p_p.h
+++ b/src/gui/rhi/qshader_p_p.h
@@ -61,6 +61,16 @@ struct Q_GUI_EXPORT QShaderPrivate
 
     static QShaderPrivate *get(QShader *s) { return s->d; }
     static const QShaderPrivate *get(const QShader *s) { return s->d; }
+    static int qtQsbVersion(QShader::SerializedFormatVersion qtVersion) {
+        switch (qtVersion) {
+        case QShader::SerializedFormatVersion::Qt_6_4:
+            return (QShaderPrivate::QSB_VERSION_WITHOUT_SEPARATE_IMAGES_AND_SAMPLERS + 1);
+        case QShader::SerializedFormatVersion::Qt_6_5:
+            return (QShaderPrivate::QSB_VERSION_WITHOUT_EXTENDED_STORAGE_BUFFER_INFO + 1);
+        default:
+            return QShaderPrivate::QSB_VERSION;
+        }
+    }
 
     QAtomicInt ref;
     int qsbVersion = QSB_VERSION;
diff --git a/src/gui/rhi/qshaderdescription.cpp b/src/gui/rhi/qshaderdescription.cpp
index 443900240a2..ca697d8edb0 100644
--- a/src/gui/rhi/qshaderdescription.cpp
+++ b/src/gui/rhi/qshaderdescription.cpp
@@ -319,13 +319,14 @@ QByteArray QShaderDescription::toJson() const
 }
 
 /*!
-    Serializes this QShaderDescription to \a stream.
+    Serializes this QShaderDescription to \a stream. \a version specifies
+    the qsb version.
 
     \sa deserialize(), toJson()
  */
-void QShaderDescription::serialize(QDataStream *stream) const
+void QShaderDescription::serialize(QDataStream *stream, int version) const
 {
-    d->writeToStream(stream);
+    d->writeToStream(stream, version);
 }
 
 /*!
@@ -1067,7 +1068,7 @@ static void addDeco(QJsonObject *obj, const QShaderDescription::InOutVariable &v
     }
 }
 
-static void serializeDecorations(QDataStream *stream, const QShaderDescription::InOutVariable &v)
+static void serializeDecorations(QDataStream *stream, const QShaderDescription::InOutVariable &v, int version)
 {
     (*stream) << v.location;
     (*stream) << v.binding;
@@ -1077,7 +1078,8 @@ static void serializeDecorations(QDataStream *stream, const QShaderDescription::
     (*stream) << int(v.arrayDims.size());
     for (int dim : v.arrayDims)
         (*stream) << dim;
-    (*stream) << quint8(v.perPatch);
+    if (version > QShaderPrivate::QSB_VERSION_WITHOUT_NATIVE_SHADER_INFO)
+        (*stream) << quint8(v.perPatch);
 }
 
 static QJsonObject inOutObject(const QShaderDescription::InOutVariable &v)
@@ -1089,11 +1091,11 @@ static QJsonObject inOutObject(const QShaderDescription::InOutVariable &v)
     return obj;
 }
 
-static void serializeInOutVar(QDataStream *stream, const QShaderDescription::InOutVariable &v)
+static void serializeInOutVar(QDataStream *stream, const QShaderDescription::InOutVariable &v, int version)
 {
     (*stream) << QString::fromUtf8(v.name);
     (*stream) << int(v.type);
-    serializeDecorations(stream, v);
+    serializeDecorations(stream, v, version);
 }
 
 static QJsonObject blockMemberObject(const QShaderDescription::BlockVariable &v)
@@ -1297,15 +1299,15 @@ QJsonDocument QShaderDescriptionPrivate::makeDoc()
     return QJsonDocument(root);
 }
 
-void QShaderDescriptionPrivate::writeToStream(QDataStream *stream)
+void QShaderDescriptionPrivate::writeToStream(QDataStream *stream, int version)
 {
     (*stream) << int(inVars.size());
     for (const QShaderDescription::InOutVariable &v : std::as_const(inVars))
-        serializeInOutVar(stream, v);
+        serializeInOutVar(stream, v, version);
 
     (*stream) << int(outVars.size());
     for (const QShaderDescription::InOutVariable &v : std::as_const(outVars))
-        serializeInOutVar(stream, v);
+        serializeInOutVar(stream, v, version);
 
     (*stream) << int(uniformBlocks.size());
     for (const QShaderDescription::UniformBlock &b : uniformBlocks) {
@@ -1338,22 +1340,24 @@ void QShaderDescriptionPrivate::writeToStream(QDataStream *stream)
         (*stream) << int(b.members.size());
         for (const QShaderDescription::BlockVariable &v : b.members)
             serializeBlockMemberVar(stream, v);
-        (*stream) << b.runtimeArrayStride;
-        (*stream) << b.qualifierFlags;
+        if (version > QShaderPrivate::QSB_VERSION_WITHOUT_EXTENDED_STORAGE_BUFFER_INFO) {
+            (*stream) << b.runtimeArrayStride;
+            (*stream) << b.qualifierFlags;
+        }
     }
 
     (*stream) << int(combinedImageSamplers.size());
     for (const QShaderDescription::InOutVariable &v : std::as_const(combinedImageSamplers)) {
         (*stream) << QString::fromUtf8(v.name);
         (*stream) << int(v.type);
-        serializeDecorations(stream, v);
+        serializeDecorations(stream, v, version);
     }
 
     (*stream) << int(storageImages.size());
     for (const QShaderDescription::InOutVariable &v : std::as_const(storageImages)) {
         (*stream) << QString::fromUtf8(v.name);
         (*stream) << int(v.type);
-        serializeDecorations(stream, v);
+        serializeDecorations(stream, v, version);
     }
 
     for (size_t i = 0; i < 3; ++i)
@@ -1363,28 +1367,30 @@ void QShaderDescriptionPrivate::writeToStream(QDataStream *stream)
     for (const QShaderDescription::InOutVariable &v : std::as_const(separateImages)) {
         (*stream) << QString::fromUtf8(v.name);
         (*stream) << int(v.type);
-        serializeDecorations(stream, v);
+        serializeDecorations(stream, v, version);
     }
 
     (*stream) << int(separateSamplers.size());
     for (const QShaderDescription::InOutVariable &v : std::as_const(separateSamplers)) {
         (*stream) << QString::fromUtf8(v.name);
         (*stream) << int(v.type);
-        serializeDecorations(stream, v);
+        serializeDecorations(stream, v, version);
     }
 
-    (*stream) << quint32(tessOutVertCount);
-    (*stream) << quint32(tessMode);
-    (*stream) << quint32(tessWind);
-    (*stream) << quint32(tessPart);
-
-    (*stream) << int(inBuiltins.size());
-    for (const QShaderDescription::BuiltinVariable &v : std::as_const(inBuiltins))
-        (*stream) << int(v.type);
-
-    (*stream) << int(outBuiltins.size());
-    for (const QShaderDescription::BuiltinVariable &v : std::as_const(outBuiltins))
-        (*stream) << int(v.type);
+    if (version > QShaderPrivate::QSB_VERSION_WITHOUT_NATIVE_SHADER_INFO) {
+        (*stream) << quint32(tessOutVertCount);
+        (*stream) << quint32(tessMode);
+        (*stream) << quint32(tessWind);
+        (*stream) << quint32(tessPart);
+
+        (*stream) << int(inBuiltins.size());
+        for (const QShaderDescription::BuiltinVariable &v : std::as_const(inBuiltins))
+            (*stream) << int(v.type);
+
+        (*stream) << int(outBuiltins.size());
+        for (const QShaderDescription::BuiltinVariable &v : std::as_const(outBuiltins))
+            (*stream) << int(v.type);
+    }
 }
 
 static void deserializeDecorations(QDataStream *stream, int version, QShaderDescription::InOutVariable *v)
diff --git a/src/gui/rhi/qshaderdescription_p.h b/src/gui/rhi/qshaderdescription_p.h
index 7e5412a784e..13e72ad134d 100644
--- a/src/gui/rhi/qshaderdescription_p.h
+++ b/src/gui/rhi/qshaderdescription_p.h
@@ -37,7 +37,7 @@ public:
 
     bool isValid() const;
 
-    void serialize(QDataStream *stream) const;
+    void serialize(QDataStream *stream, int version) const;
     QByteArray toJson() const;
 
     static QShaderDescription deserialize(QDataStream *stream, int version);
diff --git a/src/gui/rhi/qshaderdescription_p_p.h b/src/gui/rhi/qshaderdescription_p_p.h
index 1ccb7a14ed4..c22ddda8ada 100644
--- a/src/gui/rhi/qshaderdescription_p_p.h
+++ b/src/gui/rhi/qshaderdescription_p_p.h
@@ -54,7 +54,7 @@ struct Q_GUI_EXPORT QShaderDescriptionPrivate
     static const QShaderDescriptionPrivate *get(const QShaderDescription *desc) { return desc->d; }
 
     QJsonDocument makeDoc();
-    void writeToStream(QDataStream *stream);
+    void writeToStream(QDataStream *stream, int version);
     void loadFromStream(QDataStream *stream, int version);
 
     QAtomicInt ref;
diff --git a/tests/auto/gui/rhi/qshader/tst_qshader.cpp b/tests/auto/gui/rhi/qshader/tst_qshader.cpp
index 52de60ce550..425b5951d01 100644
--- a/tests/auto/gui/rhi/qshader/tst_qshader.cpp
+++ b/tests/auto/gui/rhi/qshader/tst_qshader.cpp
@@ -294,7 +294,7 @@ void tst_QShader::serializeShaderDesc()
             QBuffer buf(&data);
             QDataStream ds(&buf);
             QVERIFY(buf.open(QIODevice::WriteOnly));
-            desc.serialize(&ds);
+            desc.serialize(&ds, QShaderPrivate::QSB_VERSION);
         }
         QVERIFY(!data.isEmpty());
 
@@ -319,7 +319,7 @@ void tst_QShader::serializeShaderDesc()
             QBuffer buf(&data);
             QDataStream ds(&buf);
             QVERIFY(buf.open(QIODevice::WriteOnly));
-            desc.serialize(&ds);
+            desc.serialize(&ds, QShaderPrivate::QSB_VERSION);
         }
         QVERIFY(!data.isEmpty());