Accelerate lookup of singleton properties

Task-number: QTBUG-69898
Change-Id: Id03ba543fa293da2690099c3e6f94b2725de562f
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

4 files changed, 69 insertions, 2 deletions

diff --git a/src/qml/jsruntime/qv4lookup_p.h b/src/qml/jsruntime/qv4lookup_p.h
index ee6da21121..03dc5f6d3c 100644
--- a/src/qml/jsruntime/qv4lookup_p.h
+++ b/src/qml/jsruntime/qv4lookup_p.h
@@ -71,6 +71,7 @@ struct Lookup {
         ReturnedValue (*qmlContextPropertyGetter)(Lookup *l, ExecutionEngine *engine, Value *thisObject);
         bool (*setter)(Lookup *l, ExecutionEngine *engine, Value &object, const Value &v);
     };
+    // NOTE: gc assumes the first two entries in the struct are pointers to heap objects or null
     union {
         struct {
             Heap::Base *h1;
@@ -119,7 +120,7 @@ struct Lookup {
         } indexedLookup;
         struct {
             Heap::InternalClass *ic;
-            quintptr unused;
+            Heap::QObjectWrapper *staticQObject;
             QQmlPropertyCache *propertyCache;
             QQmlPropertyData *propertyData;
         } qobjectLookup;
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index 053581226f..351076ac28 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -867,6 +867,7 @@ ReturnedValue QObjectWrapper::virtualResolveLookupGetter(const Object *object, E
     }
 
     lookup->qobjectLookup.ic = This->internalClass();
+    lookup->qobjectLookup.staticQObject = nullptr;
     lookup->qobjectLookup.propertyCache = ddata->propertyCache;
     lookup->qobjectLookup.propertyCache->addref();
     lookup->qobjectLookup.propertyData = property;
@@ -889,7 +890,8 @@ ReturnedValue QObjectWrapper::lookupGetter(Lookup *lookup, ExecutionEngine *engi
     if (!o || o->internalClass != lookup->qobjectLookup.ic)
         return revertLookup();
 
-    const Heap::QObjectWrapper *This = static_cast<const Heap::QObjectWrapper *>(o);
+    const Heap::QObjectWrapper *This = lookup->qobjectLookup.staticQObject ? lookup->qobjectLookup.staticQObject :
+                                                                             static_cast<const Heap::QObjectWrapper *>(o);
     QObject *qobj = This->object();
     if (QQmlData::wasDeleted(qobj))
         return QV4::Encode::undefined();
diff --git a/src/qml/qml/qqmltypewrapper.cpp b/src/qml/qml/qqmltypewrapper.cpp
index 4089a7f030..d30c225741 100644
--- a/src/qml/qml/qqmltypewrapper.cpp
+++ b/src/qml/qml/qqmltypewrapper.cpp
@@ -47,6 +47,8 @@
 #include <private/qv4functionobject_p.h>
 #include <private/qv4objectproto_p.h>
 #include <private/qv4qobjectwrapper_p.h>
+#include <private/qv4identifiertable_p.h>
+#include <private/qv4lookup_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -169,6 +171,7 @@ static ReturnedValue throwLowercaseEnumError(QV4::ExecutionEngine *v4, String *n
 
 ReturnedValue QQmlTypeWrapper::virtualGet(const Managed *m, PropertyKey id, const Value *receiver, bool *hasProperty)
 {
+    // Keep this code in sync with ::virtualResolveLookupGetter
     Q_ASSERT(m->as<QQmlTypeWrapper>());
 
     if (!id.isString())
@@ -425,6 +428,64 @@ ReturnedValue QQmlTypeWrapper::virtualInstanceOf(const Object *typeObject, const
     return QV4::Encode(QQmlMetaObject::canConvert(theirType, myQmlType));
 }
 
+ReturnedValue QQmlTypeWrapper::virtualResolveLookupGetter(const Object *object, ExecutionEngine *engine, Lookup *lookup)
+{
+    // Keep this code in sync with ::virtualGet
+    PropertyKey id = engine->identifierTable->asPropertyKey(engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[lookup->nameIndex]);
+    if (!id.isString())
+        return Object::virtualResolveLookupGetter(object, engine, lookup);
+    Scope scope(engine);
+
+    const QQmlTypeWrapper *This = static_cast<const QQmlTypeWrapper *>(object);
+    ScopedString name(scope, id.asStringOrSymbol());
+    QQmlContextData *qmlContext = engine->callingQmlContext();
+
+    Scoped<QQmlTypeWrapper> w(scope, static_cast<const QQmlTypeWrapper *>(This));
+    QQmlType type = w->d()->type();
+
+    if (type.isValid()) {
+
+        if (type.isSingleton()) {
+            QQmlEngine *e = engine->qmlEngine();
+            QQmlType::SingletonInstanceInfo *siinfo = type.singletonInstanceInfo();
+            siinfo->init(e);
+
+            QObject *qobjectSingleton = siinfo->qobjectApi(e);
+            if (qobjectSingleton) {
+
+                const bool includeEnums = w->d()->mode == Heap::QQmlTypeWrapper::IncludeEnums;
+                if (!includeEnums || !name->startsWithUpper()) {
+                    QQmlData *ddata = QQmlData::get(qobjectSingleton, false);
+                    if (ddata && ddata->propertyCache) {
+                        ScopedValue val(scope, Value::fromReturnedValue(QV4::QObjectWrapper::wrap(engine, qobjectSingleton)));
+                        QQmlPropertyData *property = ddata->propertyCache->property(name.getPointer(), qobjectSingleton, qmlContext);
+                        if (property) {
+                            lookup->qobjectLookup.ic = This->internalClass();
+                            lookup->qobjectLookup.staticQObject = static_cast<Heap::QObjectWrapper *>(val->heapObject());
+                            lookup->qobjectLookup.propertyCache = ddata->propertyCache;
+                            lookup->qobjectLookup.propertyCache->addref();
+                            lookup->qobjectLookup.propertyData = property;
+                            lookup->getter = QV4::QObjectWrapper::lookupGetter;
+                            return lookup->getter(lookup, engine, *This);
+                        }
+                        // Fall through to base implementation
+                    }
+                    // Fall through to base implementation
+                }
+                // Fall through to base implementation
+            }
+            // Fall through to base implementation
+        }
+        // Fall through to base implementation
+    }
+    return QV4::Object::virtualResolveLookupGetter(object, engine, lookup);
+}
+
+bool QQmlTypeWrapper::virtualResolveLookupSetter(Object *object, ExecutionEngine *engine, Lookup *lookup, const Value &value)
+{
+    return Object::virtualResolveLookupSetter(object, engine, lookup, value);
+}
+
 void Heap::QQmlScopedEnumWrapper::destroy()
 {
     QQmlType::derefHandle(typePrivate);
diff --git a/src/qml/qml/qqmltypewrapper_p.h b/src/qml/qml/qqmltypewrapper_p.h
index fa1ad56902..44e82dec2b 100644
--- a/src/qml/qml/qqmltypewrapper_p.h
+++ b/src/qml/qml/qqmltypewrapper_p.h
@@ -111,6 +111,9 @@ struct Q_QML_EXPORT QQmlTypeWrapper : Object
     static ReturnedValue create(ExecutionEngine *, QObject *, const QQmlRefPointer<QQmlTypeNameCache> &, const QQmlImportRef *,
                                 Heap::QQmlTypeWrapper::TypeNameMode = Heap::QQmlTypeWrapper::IncludeEnums);
 
+    static ReturnedValue virtualResolveLookupGetter(const Object *object, ExecutionEngine *engine, Lookup *lookup);
+    static bool virtualResolveLookupSetter(Object *object, ExecutionEngine *engine, Lookup *lookup, const Value &value);
+
 protected:
     static ReturnedValue virtualGet(const Managed *m, PropertyKey id, const Value *receiver, bool *hasProperty);
     static bool virtualPut(Managed *m, PropertyKey id, const Value &value, Value *receiver);