Reduce the size of Property fields in type compilation data

We can shave off 4 bytes of each property declaration by sharing the
bits for the custom type name index or the builtin type enum.

Change-Id: I77071cbef66c5a83b3e7e281dba3a435d3c68b39
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

5 files changed, 81 insertions, 69 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index 8bdbab3b5a..6c61473418 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -872,13 +872,15 @@ bool IRBuilder::visit(QQmlJS::AST::UiPublicMember *node)
         } else {
             const QStringRef &name = node->name;
 
+            Property *property = New<Property>();
+            property->isReadOnly = node->isReadonlyMember;
+
             bool typeFound = false;
-            QV4::CompiledData::Property::Type type = QV4::CompiledData::Property::Var;
 
             for (int ii = 0; !typeFound && ii < propTypeNameToTypesCount; ++ii) {
                 const TypeNameToType *t = propTypeNameToTypes + ii;
                 if (memberType == QLatin1String(t->name, static_cast<int>(t->nameLength))) {
-                    type = t->type;
+                    property->setBuiltinType(t->type);
                     typeFound = true;
                 }
             }
@@ -886,11 +888,10 @@ bool IRBuilder::visit(QQmlJS::AST::UiPublicMember *node)
             if (!typeFound && memberType.at(0).isUpper()) {
                 const QStringRef &typeModifier = node->typeModifier;
 
-                if (typeModifier.isEmpty()) {
-                    type = QV4::CompiledData::Property::Custom;
-                } else if (typeModifier == QLatin1String("list")) {
-                    type = QV4::CompiledData::Property::CustomList;
-                } else {
+                property->setCustomType(registerString(memberType));
+                if (typeModifier == QLatin1String("list")) {
+                    property->isList = true;
+                } else if (!typeModifier.isEmpty()) {
                     recordError(node->typeModifierToken, QCoreApplication::translate("QQmlParser","Invalid property type modifier"));
                     return false;
                 }
@@ -905,14 +906,6 @@ bool IRBuilder::visit(QQmlJS::AST::UiPublicMember *node)
                 return false;
             }
 
-            Property *property = New<Property>();
-            property->isReadOnly = node->isReadonlyMember;
-            property->type = type;
-            if (type >= QV4::CompiledData::Property::Custom)
-                property->customTypeNameIndex = registerString(memberType);
-            else
-                property->customTypeNameIndex = emptyStringIndex;
-
             const QString propName = name.toString();
             property->nameIndex = registerString(propName);
 
@@ -1530,7 +1523,7 @@ bool IRBuilder::isStatementNodeScript(QQmlJS::AST::Statement *statement)
 
 bool IRBuilder::isRedundantNullInitializerForPropertyDeclaration(Property *property, QQmlJS::AST::Statement *statement)
 {
-    if (property->type != QV4::CompiledData::Property::Custom)
+    if (property->isBuiltinType || property->isList)
         return false;
     QQmlJS::AST::ExpressionStatement *exprStmt = QQmlJS::AST::cast<QQmlJS::AST::ExpressionStatement *>(statement);
     if (!exprStmt)
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 9123f9f0ec..639595509a 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -642,18 +642,35 @@ struct Property
 {
     enum Type : unsigned int { Var = 0, Variant, Int, Bool, Real, String, Url, Color,
                 Font, Time, Date, DateTime, Rect, Point, Size,
-                Vector2D, Vector3D, Vector4D, Matrix4x4, Quaternion,
-                Custom, CustomList };
+                Vector2D, Vector3D, Vector4D, Matrix4x4, Quaternion, InvalidBuiltin };
 
     quint32_le nameIndex;
     union {
-        quint32_le_bitfield<0, 31> type;
+        quint32_le_bitfield<0, 29> builtinTypeOrTypeNameIndex;
+        quint32_le_bitfield<29, 1> isBuiltinType;
+        quint32_le_bitfield<30, 1> isList;
         quint32_le_bitfield<31, 1> isReadOnly;
     };
-    quint32_le customTypeNameIndex; // If type >= Custom
+
     Location location;
+
+    void setBuiltinType(Type t)
+    {
+        builtinTypeOrTypeNameIndex = t;
+        isBuiltinType = true;
+    }
+    Type builtinType() const {
+        if (isBuiltinType)
+            return static_cast<Type>(quint32(builtinTypeOrTypeNameIndex));
+        return InvalidBuiltin;
+    }
+    void setCustomType(int nameIndex)
+    {
+        builtinTypeOrTypeNameIndex = nameIndex;
+        isBuiltinType = false;
+    }
 };
-static_assert(sizeof(Property) == 16, "Property structure needs to have the expected size to be binary compatible on disk when generated by host compiler and loaded by target");
+static_assert(sizeof(Property) == 12, "Property structure needs to have the expected size to be binary compatible on disk when generated by host compiler and loaded by target");
 
 struct Alias {
     enum Flags : unsigned int {
@@ -1044,8 +1061,8 @@ struct TypeReferenceMap : QHash<int, TypeReference>
         auto prop = obj->propertiesBegin();
         auto propEnd = obj->propertiesEnd();
         for ( ; prop != propEnd; ++prop) {
-            if (prop->type >= QV4::CompiledData::Property::Custom) {
-                TypeReference &r = this->add(prop->customTypeNameIndex, prop->location);
+            if (!prop->isBuiltinType) {
+                TypeReference &r = this->add(prop->builtinTypeOrTypeNameIndex, prop->location);
                 r.errorWhenNotFound = true;
             }
         }
diff --git a/src/qml/qml/qqmlpropertycachecreator.cpp b/src/qml/qml/qqmlpropertycachecreator.cpp
index 822241d58c..6e492f7a80 100644
--- a/src/qml/qml/qqmlpropertycachecreator.cpp
+++ b/src/qml/qml/qqmlpropertycachecreator.cpp
@@ -69,8 +69,7 @@ int QQmlPropertyCacheCreatorBase::metaTypeForPropertyType(QV4::CompiledData::Pro
     case QV4::CompiledData::Property::Vector4D: return QMetaType::QVector4D;
     case QV4::CompiledData::Property::Matrix4x4: return QMetaType::QMatrix4x4;
     case QV4::CompiledData::Property::Quaternion: return QMetaType::QQuaternion;
-    case QV4::CompiledData::Property::Custom: break;
-    case QV4::CompiledData::Property::CustomList: break;
+    case QV4::CompiledData::Property::InvalidBuiltin: break;
     };
     return QMetaType::UnknownType;
 }
diff --git a/src/qml/qml/qqmlpropertycachecreator_p.h b/src/qml/qml/qqmlpropertycachecreator_p.h
index e227301175..5421e2c61b 100644
--- a/src/qml/qml/qqmlpropertycachecreator_p.h
+++ b/src/qml/qml/qqmlpropertycachecreator_p.h
@@ -304,7 +304,7 @@ inline QQmlJS::DiagnosticMessage QQmlPropertyCacheCreator<ObjectContainer>::crea
     auto p = obj->propertiesBegin();
     auto pend = obj->propertiesEnd();
     for ( ; p != pend; ++p) {
-        if (p->type == QV4::CompiledData::Property::Var)
+        if (p->builtinType() == QV4::CompiledData::Property::Var)
             varPropCount++;
 
         bool notInRevision = false;
@@ -477,20 +477,22 @@ inline QQmlJS::DiagnosticMessage QQmlPropertyCacheCreator<ObjectContainer>::crea
         int propertTypeMinorVersion = 0;
         QQmlPropertyData::Flags propertyFlags;
 
-        if (p->type == QV4::CompiledData::Property::Var) {
-            propertyType = QMetaType::QVariant;
+        const QV4::CompiledData::Property::Type type = p->builtinType();
+
+        if (type == QV4::CompiledData::Property::Var)
             propertyFlags.type = QQmlPropertyData::Flags::VarPropertyType;
-        } else if (p->type < QV4::CompiledData::Property::Custom) {
-            propertyType = metaTypeForPropertyType(static_cast<QV4::CompiledData::Property::Type>(quint32(p->type)));
 
-            if (p->type == QV4::CompiledData::Property::Variant)
+
+        if (type != QV4::CompiledData::Property::InvalidBuiltin) {
+            propertyType = metaTypeForPropertyType(type);
+
+            if (type == QV4::CompiledData::Property::Variant)
                 propertyFlags.type = QQmlPropertyData::Flags::QVariantType;
         } else {
-            Q_ASSERT(p->type == QV4::CompiledData::Property::CustomList ||
-                     p->type == QV4::CompiledData::Property::Custom);
+            Q_ASSERT(!p->isBuiltinType);
 
             QQmlType qmltype;
-            if (!imports->resolveType(stringAt(p->customTypeNameIndex), &qmltype, nullptr, nullptr, nullptr)) {
+            if (!imports->resolveType(stringAt(p->builtinTypeOrTypeNameIndex), &qmltype, nullptr, nullptr, nullptr)) {
                 return qQmlCompileError(p->location, QQmlPropertyCacheCreatorBase::tr("Invalid property type"));
             }
 
@@ -502,27 +504,27 @@ inline QQmlJS::DiagnosticMessage QQmlPropertyCacheCreator<ObjectContainer>::crea
 
                 auto compilationUnit = tdata->compilationUnit();
 
-                if (p->type == QV4::CompiledData::Property::Custom) {
-                    propertyType = compilationUnit->metaTypeId;
-                } else {
+                if (p->isList) {
                     propertyType = compilationUnit->listMetaTypeId;
+                } else {
+                    propertyType = compilationUnit->metaTypeId;
                 }
             } else {
-                if (p->type == QV4::CompiledData::Property::Custom) {
+                if (p->isList) {
+                    propertyType = qmltype.qListTypeId();
+                } else {
                     propertyType = qmltype.typeId();
                     propertTypeMinorVersion = qmltype.minorVersion();
-                } else {
-                    propertyType = qmltype.qListTypeId();
                 }
             }
 
-            if (p->type == QV4::CompiledData::Property::Custom)
-                propertyFlags.type = QQmlPropertyData::Flags::QObjectDerivedType;
-            else
+            if (p->isList)
                 propertyFlags.type = QQmlPropertyData::Flags::QListType;
+            else
+                propertyFlags.type = QQmlPropertyData::Flags::QObjectDerivedType;
         }
 
-        if (!p->isReadOnly && p->type != QV4::CompiledData::Property::CustomList)
+        if (!p->isReadOnly && !p->isList)
             propertyFlags.isWritable = true;
 
 
diff --git a/src/qml/qml/qqmlvmemetaobject.cpp b/src/qml/qml/qqmlvmemetaobject.cpp
index e26dc4d9aa..d210b049df 100644
--- a/src/qml/qml/qqmlvmemetaobject.cpp
+++ b/src/qml/qml/qqmlvmemetaobject.cpp
@@ -639,7 +639,8 @@ int QQmlVMEMetaObject::metaCall(QObject *o, QMetaObject::Call c, int _id, void *
             id -= propOffset();
 
             if (id < propertyCount) {
-                const QV4::CompiledData::Property::Type t = static_cast<QV4::CompiledData::Property::Type>(qint32(compiledObject->propertyTable()[id].type));
+                const QV4::CompiledData::Property &property = compiledObject->propertyTable()[id];
+                const QV4::CompiledData::Property::Type t = property.builtinType();
 
                 // the context can be null if accessing var properties from cpp after re-parenting an item.
                 QQmlEnginePrivate *ep = (ctxt == nullptr || ctxt->engine == nullptr) ? nullptr : QQmlEnginePrivate::get(ctxt->engine);
@@ -678,22 +679,9 @@ int QQmlVMEMetaObject::metaCall(QObject *o, QMetaObject::Call c, int _id, void *
                     case QV4::CompiledData::Property::Point:
                         *reinterpret_cast<QPointF *>(a[0]) = readPropertyAsPointF(id);
                         break;
-                    case QV4::CompiledData::Property::Custom:
-                        *reinterpret_cast<QObject **>(a[0]) = readPropertyAsQObject(id);
-                        break;
                     case QV4::CompiledData::Property::Variant:
                         *reinterpret_cast<QVariant *>(a[0]) = readPropertyAsVariant(id);
                         break;
-                    case QV4::CompiledData::Property::CustomList: {
-                        QList<QObject *> *list = readPropertyAsList(id);
-                        QQmlListProperty<QObject> *p = static_cast<QQmlListProperty<QObject> *>(a[0]);
-                        *p = QQmlListProperty<QObject>(object, list,
-                                                       list_append, list_count, list_at,
-                                                       list_clear);
-                        p->dummy1 = this;
-                        p->dummy2 = reinterpret_cast<void *>(quintptr(methodOffset() + id));
-                        break;
-                    }
                     case QV4::CompiledData::Property::Font:
                     case QV4::CompiledData::Property::Time:
                     case QV4::CompiledData::Property::Color:
@@ -718,6 +706,18 @@ int QQmlVMEMetaObject::metaCall(QObject *o, QMetaObject::Call c, int _id, void *
                             *reinterpret_cast<QVariant *>(a[0]) = QVariant();
                         }
                         break;
+                    case QV4::CompiledData::Property::InvalidBuiltin:
+                        if (property.isList) {
+                            QList<QObject *> *list = readPropertyAsList(id);
+                            QQmlListProperty<QObject> *p = static_cast<QQmlListProperty<QObject> *>(a[0]);
+                            *p = QQmlListProperty<QObject>(object, list,
+                                                           list_append, list_count, list_at,
+                                                           list_clear);
+                            p->dummy1 = this;
+                            p->dummy2 = reinterpret_cast<void *>(quintptr(methodOffset() + id));
+                        } else {
+                            *reinterpret_cast<QObject **>(a[0]) = readPropertyAsQObject(id);
+                        }
                     }
 
                 } else if (c == QMetaObject::WriteProperty) {
@@ -763,17 +763,9 @@ int QQmlVMEMetaObject::metaCall(QObject *o, QMetaObject::Call c, int _id, void *
                         needActivate = *reinterpret_cast<QPointF *>(a[0]) != readPropertyAsPointF(id);
                         writeProperty(id, *reinterpret_cast<QPointF *>(a[0]));
                         break;
-                    case QV4::CompiledData::Property::Custom:
-                        needActivate = *reinterpret_cast<QObject **>(a[0]) != readPropertyAsQObject(id);
-                        writeProperty(id, *reinterpret_cast<QObject **>(a[0]));
-                        break;
                     case QV4::CompiledData::Property::Variant:
                         writeProperty(id, *reinterpret_cast<QVariant *>(a[0]));
                         break;
-                    case QV4::CompiledData::Property::CustomList:
-                        // Writing such a property is not supported. Content is added through the list property
-                        // methods.
-                        break;
                     case QV4::CompiledData::Property::Font:
                     case QV4::CompiledData::Property::Time:
                     case QV4::CompiledData::Property::Color:
@@ -798,6 +790,15 @@ int QQmlVMEMetaObject::metaCall(QObject *o, QMetaObject::Call c, int _id, void *
                         if (ep)
                             writeProperty(id, *reinterpret_cast<QVariant *>(a[0]));
                         break;
+                    case QV4::CompiledData::Property::InvalidBuiltin:
+                        if (property.isList) {
+                            // Writing such a property is not supported. Content is added through the list property
+                            // methods.
+                        } else {
+                            needActivate = *reinterpret_cast<QObject **>(a[0]) != readPropertyAsQObject(id);
+                            writeProperty(id, *reinterpret_cast<QObject **>(a[0]));
+                        }
+
                     }
 
                     if (needActivate)
@@ -965,7 +966,7 @@ QV4::ReturnedValue QQmlVMEMetaObject::method(int index) const
 
 QV4::ReturnedValue QQmlVMEMetaObject::readVarProperty(int id) const
 {
-    Q_ASSERT(compiledObject && compiledObject->propertyTable()[id].type == QV4::CompiledData::Property::Var);
+    Q_ASSERT(compiledObject && compiledObject->propertyTable()[id].builtinType() == QV4::CompiledData::Property::Var);
 
     QV4::MemberData *md = propertyAndMethodStorageAsMemberData();
     if (md)
@@ -990,7 +991,7 @@ QVariant QQmlVMEMetaObject::readPropertyAsVariant(int id) const
 
 void QQmlVMEMetaObject::writeVarProperty(int id, const QV4::Value &value)
 {
-    Q_ASSERT(compiledObject && compiledObject->propertyTable()[id].type == QV4::CompiledData::Property::Var);
+    Q_ASSERT(compiledObject && compiledObject->propertyTable()[id].builtinType() == QV4::CompiledData::Property::Var);
 
     QV4::MemberData *md = propertyAndMethodStorageAsMemberData();
     if (!md)
@@ -1030,7 +1031,7 @@ void QQmlVMEMetaObject::writeVarProperty(int id, const QV4::Value &value)
 
 void QQmlVMEMetaObject::writeProperty(int id, const QVariant &value)
 {
-    if (compiledObject && compiledObject->propertyTable()[id].type == QV4::CompiledData::Property::Var) {
+    if (compiledObject && compiledObject->propertyTable()[id].builtinType() == QV4::CompiledData::Property::Var) {
         QV4::MemberData *md = propertyAndMethodStorageAsMemberData();
         if (!md)
             return;