V4: create a fast-path for QObjectWrapper::wrap

The typical case is that there's already a QQmlData for a QObject, so
fast-path this, and fall back to the general case if there is none (or
it is deleted, etc.)

Change-Id: I00c890e5fe7abdd743c4e99316a7ce93eb3db9df
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>

2 files changed, 21 insertions, 5 deletions

diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index 3be32c7920..462c4f3171 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -560,7 +560,7 @@ void QObjectWrapper::setProperty(ExecutionEngine *engine, QObject *object, QQmlP
     }
 }
 
-ReturnedValue QObjectWrapper::wrap(ExecutionEngine *engine, QObject *object)
+ReturnedValue QObjectWrapper::wrap_slowPath(ExecutionEngine *engine, QObject *object)
 {
     if (QQmlData::wasDeleted(object))
         return QV4::Encode::null();
@@ -571,10 +571,7 @@ ReturnedValue QObjectWrapper::wrap(ExecutionEngine *engine, QObject *object)
 
     Scope scope(engine);
 
-    if (ddata->jsEngineId == engine->m_engineId && !ddata->jsWrapper.isUndefined()) {
-        // We own the JS object
-        return ddata->jsWrapper.value();
-    } else if (ddata->jsWrapper.isUndefined() &&
+    if (ddata->jsWrapper.isUndefined() &&
                (ddata->jsEngineId == engine->m_engineId || // We own the QObject
                 ddata->jsEngineId == 0 ||    // No one owns the QObject
                 !ddata->hasTaintedV4Object)) { // Someone else has used the QObject, but it isn't tainted
diff --git a/src/qml/jsruntime/qv4qobjectwrapper_p.h b/src/qml/jsruntime/qv4qobjectwrapper_p.h
index d25279e783..d2650efd58 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper_p.h
+++ b/src/qml/jsruntime/qv4qobjectwrapper_p.h
@@ -145,8 +145,27 @@ protected:
 
     static ReturnedValue method_connect(CallContext *ctx);
     static ReturnedValue method_disconnect(CallContext *ctx);
+
+private:
+    static ReturnedValue wrap_slowPath(ExecutionEngine *engine, QObject *object);
 };
 
+inline ReturnedValue QObjectWrapper::wrap(ExecutionEngine *engine, QObject *object)
+{
+    if (Q_LIKELY(!QQmlData::wasDeleted(object))) {
+        QObjectPrivate *priv = QObjectPrivate::get(const_cast<QObject *>(object));
+        if (Q_LIKELY(priv->declarativeData)) {
+            auto ddata = static_cast<QQmlData *>(priv->declarativeData);
+            if (Q_LIKELY(ddata->jsEngineId == engine->m_engineId && !ddata->jsWrapper.isUndefined())) {
+                // We own the JS object
+                return ddata->jsWrapper.value();
+            }
+        }
+    }
+
+    return wrap_slowPath(engine, object);
+}
+
 struct QQmlValueTypeWrapper;
 
 struct Q_QML_EXPORT QObjectMethod : public QV4::FunctionObject