Move property cache from the engine to QQmlType

Now that the property cache is independent of a specific
engine, we can cache them in QQmlType instead of caching
them per engine.

This simplifies the logic and avoids duplicated property
caches when multiple engines are running.

Task-number: QTBUG-61536
Change-Id: I6f082e1e7495ae0f5b92559e8d0a3437c56e303a
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

3 files changed, 34 insertions, 0 deletions

diff --git a/src/qml/qml/qqmlmetatype.cpp b/src/qml/qml/qqmlmetatype.cpp
index 3e29222200..a2b6913943 100644
--- a/src/qml/qml/qqmlmetatype.cpp
+++ b/src/qml/qml/qqmlmetatype.cpp
@@ -110,6 +110,9 @@ struct QQmlMetaTypeData
 
     QString typeRegistrationNamespace;
     QStringList typeRegistrationFailures;
+
+    QHash<const QMetaObject *, QQmlPropertyCache *> propertyCaches;
+    QQmlPropertyCache *propertyCache(const QMetaObject *metaObject);
 };
 
 class QQmlTypeModulePrivate
@@ -151,6 +154,9 @@ QQmlMetaTypeData::~QQmlMetaTypeData()
 
     for (TypeModules::const_iterator i = uriToModule.constBegin(), cend = uriToModule.constEnd(); i != cend; ++i)
         delete *i;
+    for (QHash<const QMetaObject *, QQmlPropertyCache *>::Iterator it = propertyCaches.begin(), end = propertyCaches.end();
+         it != end; ++it)
+        (*it)->release();
 }
 
 class QQmlTypePrivate
@@ -1981,6 +1987,29 @@ QQmlType QQmlMetaType::qmlTypeFromIndex(int idx)
     return data->types.at(idx);
 }
 
+QQmlPropertyCache *QQmlMetaTypeData::propertyCache(const QMetaObject *metaObject)
+{
+    if (QQmlPropertyCache *rv = propertyCaches.value(metaObject))
+        return rv;
+
+    if (!metaObject->superClass()) {
+        QQmlPropertyCache *rv = new QQmlPropertyCache(metaObject);
+        propertyCaches.insert(metaObject, rv);
+        return rv;
+    }
+    QQmlPropertyCache *super = propertyCache(metaObject->superClass());
+    QQmlPropertyCache *rv = super->copyAndAppend(metaObject);
+    propertyCaches.insert(metaObject, rv);
+    return rv;
+}
+
+QQmlPropertyCache *QQmlMetaType::propertyCache(const QMetaObject *metaObject)
+{
+    QMutexLocker lock(metaTypeDataLock());
+    QQmlMetaTypeData *data = metaTypeData();
+    return data->propertyCache(metaObject);
+}
+
 /*!
     Returns the list of registered QML type names.
 */
diff --git a/src/qml/qml/qqmlmetatype_p.h b/src/qml/qml/qqmlmetatype_p.h
index d17172a917..c577a9cc18 100644
--- a/src/qml/qml/qqmlmetatype_p.h
+++ b/src/qml/qml/qqmlmetatype_p.h
@@ -70,6 +70,7 @@ class QQmlTypeModule;
 class QHashedString;
 class QHashedStringRef;
 class QMutex;
+class QQmlPropertyCache;
 
 namespace QV4 { struct String; }
 
@@ -89,6 +90,8 @@ public:
     static QQmlType qmlType(const QUrl &url, bool includeNonFileImports = false);
     static QQmlType qmlTypeFromIndex(int);
 
+    static QQmlPropertyCache *propertyCache(const QMetaObject *metaObject);
+
     static QMetaProperty defaultProperty(const QMetaObject *);
     static QMetaProperty defaultProperty(QObject *);
     static QMetaMethod defaultMethod(const QMetaObject *);
diff --git a/src/qml/qml/qqmlpropertycache_p.h b/src/qml/qml/qqmlpropertycache_p.h
index 6444d8800a..8fdc95af3a 100644
--- a/src/qml/qml/qqmlpropertycache_p.h
+++ b/src/qml/qml/qqmlpropertycache_p.h
@@ -511,6 +511,8 @@ private:
     QByteArray _checksum;
 };
 
+typedef QQmlRefPointer<QQmlPropertyCache> QQmlPropertyCachePtr;
+
 // QQmlMetaObject serves as a wrapper around either QMetaObject or QQmlPropertyCache.
 // This is necessary as we delay creation of QMetaObject for synthesized QObjects, but
 // we don't want to needlessly generate QQmlPropertyCaches every time we encounter a