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>

2 files changed, 4 insertions, 32 deletions

diff --git a/src/qml/jsapi/qjsengine.cpp b/src/qml/jsapi/qjsengine.cpp
index 17f3fcedae..35b4929c3a 100644
--- a/src/qml/jsapi/qjsengine.cpp
+++ b/src/qml/jsapi/qjsengine.cpp
@@ -730,10 +730,7 @@ QJSEnginePrivate *QJSEnginePrivate::get(QV4::ExecutionEngine *e)
 
 QJSEnginePrivate::~QJSEnginePrivate()
 {
-    typedef QHash<const QMetaObject *, QQmlPropertyCache *>::Iterator PropertyCacheIt;
-
-    for (PropertyCacheIt iter = propertyCache.begin(), end = propertyCache.end(); iter != end; ++iter)
-        (*iter)->release();
+    // ### FIXME: sweep unused QQmlType instances
 }
 
 void QJSEnginePrivate::addToDebugServer(QJSEngine *q)
@@ -756,20 +753,6 @@ void QJSEnginePrivate::removeFromDebugServer(QJSEngine *q)
         server->removeEngine(q);
 }
 
-QQmlPropertyCache *QJSEnginePrivate::createCache(const QMetaObject *mo)
-{
-    if (!mo->superClass()) {
-        QQmlPropertyCache *rv = new QQmlPropertyCache(mo);
-        propertyCache.insert(mo, rv);
-        return rv;
-    } else {
-        QQmlPropertyCache *super = cache(mo->superClass());
-        QQmlPropertyCache *rv = super->copyAndAppend(mo);
-        propertyCache.insert(mo, rv);
-        return rv;
-    }
-}
-
 /*!
    \since 5.5
    \relates QJSEngine
diff --git a/src/qml/jsapi/qjsengine_p.h b/src/qml/jsapi/qjsengine_p.h
index 2b462451ed..cbfe0f14a3 100644
--- a/src/qml/jsapi/qjsengine_p.h
+++ b/src/qml/jsapi/qjsengine_p.h
@@ -55,6 +55,7 @@
 #include <QtCore/qmutex.h>
 #include "qjsengine.h"
 #include "private/qtqmlglobal_p.h"
+#include <private/qqmlmetatype_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -110,14 +111,6 @@ public:
     // These methods may be called from the QML loader thread
     inline QQmlPropertyCache *cache(QObject *obj);
     inline QQmlPropertyCache *cache(const QMetaObject *);
-
-private:
-    // Must be called locked
-    QQmlPropertyCache *createCache(const QMetaObject *);
-
-    // These members must be protected by a QJSEnginePrivate::Locker as they are required by
-    // the threaded loader.  Only access them through their respective accessor methods.
-    QHash<const QMetaObject *, QQmlPropertyCache *> propertyCache;
 };
 
 QJSEnginePrivate::Locker::Locker(const QJSEngine *e)
@@ -174,9 +167,7 @@ QQmlPropertyCache *QJSEnginePrivate::cache(QObject *obj)
 
     Locker locker(this);
     const QMetaObject *mo = obj->metaObject();
-    QQmlPropertyCache *rv = propertyCache.value(mo);
-    if (!rv) rv = createCache(mo);
-    return rv;
+    return QQmlMetaType::propertyCache(mo);
 }
 
 /*!
@@ -193,9 +184,7 @@ QQmlPropertyCache *QJSEnginePrivate::cache(const QMetaObject *metaObject)
     Q_ASSERT(metaObject);
 
     Locker locker(this);
-    QQmlPropertyCache *rv = propertyCache.value(metaObject);
-    if (!rv) rv = createCache(metaObject);
-    return rv;
+    return QQmlMetaType::propertyCache(metaObject);
 }