Add the object's prototype to the InternalClass structure

Change-Id: Ifa97d3354a7a7afadf70f9ba540716bd5b1eef44
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

3 files changed, 39 insertions, 2 deletions

diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index a8a169f486..08093ca24c 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -714,6 +714,8 @@ void ExecutionEngine::markObjects()
     if (m_qmlExtensions)
         m_qmlExtensions->markObjects();
 
+    emptyClass->markObjects();
+
     for (QSet<CompiledData::CompilationUnit*>::ConstIterator it = compilationUnits.constBegin(), end = compilationUnits.constEnd();
          it != end; ++it)
         (*it)->markObjects();
diff --git a/src/qml/jsruntime/qv4internalclass.cpp b/src/qml/jsruntime/qv4internalclass.cpp
index f4edc99545..50803db73d 100644
--- a/src/qml/jsruntime/qv4internalclass.cpp
+++ b/src/qml/jsruntime/qv4internalclass.cpp
@@ -126,6 +126,7 @@ uint PropertyHash::lookup(const Identifier *identifier) const
 
 InternalClass::InternalClass(const QV4::InternalClass &other)
     : engine(other.engine)
+    , prototype(other.prototype)
     , propertyTable(other.propertyTable)
     , nameMap(other.nameMap)
     , propertyData(other.propertyData)
@@ -163,6 +164,25 @@ InternalClass *InternalClass::changeMember(String *string, PropertyAttributes da
 
 }
 
+InternalClass *InternalClass::changePrototype(Object *proto)
+{
+    if (prototype == proto)
+        return this;
+
+    Transition t;
+    t.prototype = proto;
+    t.flags = Transition::ProtoChange;
+
+    QHash<Transition, InternalClass *>::const_iterator tit = transitions.constFind(t);
+    if (tit != transitions.constEnd())
+        return tit.value();
+
+    // create a new class and add it to the tree
+    InternalClass *newClass = engine->newClass(*this);
+    newClass->prototype = proto;
+    return newClass;
+}
+
 InternalClass *InternalClass::addMember(String *string, PropertyAttributes data, uint *index)
 {
 //    qDebug() << "InternalClass::addMember()" << string->toQString() << size << hex << (uint)data.m_all << data.type();
@@ -293,4 +313,12 @@ void InternalClass::destroy()
     transitions.clear();
 }
 
+void InternalClass::markObjects()
+{
+    prototype->mark();
+    for (QHash<Transition, InternalClass *>::ConstIterator it = transitions.begin(), end = transitions.end();
+         it != end; ++it)
+        it.value()->markObjects();
+}
+
 QT_END_NAMESPACE
diff --git a/src/qml/jsruntime/qv4internalclass_p.h b/src/qml/jsruntime/qv4internalclass_p.h
index fc6c5352b1..1fba947a37 100644
--- a/src/qml/jsruntime/qv4internalclass_p.h
+++ b/src/qml/jsruntime/qv4internalclass_p.h
@@ -108,8 +108,12 @@ inline PropertyHash::~PropertyHash()
 
 struct InternalClassTransition
 {
-    Identifier *id;
+    union {
+        Identifier *id;
+        Object *prototype;
+    };
     int flags;
+    enum { ProtoChange = 0x100 };
 
     bool operator==(const InternalClassTransition &other) const
     { return id == other.id && flags == other.flags; }
@@ -118,6 +122,7 @@ uint qHash(const QV4::InternalClassTransition &t, uint = 0);
 
 struct InternalClass {
     ExecutionEngine *engine;
+    Object *prototype;
     PropertyHash propertyTable; // id to valueIndex
     QVector<String *> nameMap;
 
@@ -131,6 +136,7 @@ struct InternalClass {
 
     uint size;
 
+    InternalClass *changePrototype(Object *proto);
     InternalClass *addMember(String *string, PropertyAttributes data, uint *index = 0);
     InternalClass *changeMember(String *string, PropertyAttributes data, uint *index = 0);
     void removeMember(Object *object, Identifier *id);
@@ -140,10 +146,11 @@ struct InternalClass {
     InternalClass *frozen();
 
     void destroy();
+    void markObjects();
 
 private:
     friend struct ExecutionEngine;
-    InternalClass(ExecutionEngine *engine) : engine(engine), m_sealed(0), m_frozen(0), size(0) {}
+    InternalClass(ExecutionEngine *engine) : engine(engine), prototype(0), m_sealed(0), m_frozen(0), size(0) {}
     InternalClass(const InternalClass &other);
 };