Object property binding optimization

Add a binding optimization that hits
    anchors.fill: parent

10 files changed, 202 insertions, 24 deletions

diff --git a/src/declarative/qml/qmlbasicscript.cpp b/src/declarative/qml/qmlbasicscript.cpp
index 8993845..f3f9289 100644
--- a/src/declarative/qml/qmlbasicscript.cpp
+++ b/src/declarative/qml/qmlbasicscript.cpp
@@ -714,6 +714,23 @@ int QmlBasicScript::singleIdFetchIndex() const
     return d->instructions()[0].fetch.idx;
 }
 
+bool QmlBasicScript::isSingleContextProperty() const
+{
+    if (!isValid())
+        return false;
+
+    return d->instructionCount == 1 && 
+           d->instructions()[0].type == ScriptInstruction::FetchContextConstant;
+}
+
+int QmlBasicScript::singleContextPropertyIndex() const
+{
+    if (!isSingleContextProperty())
+        return -1;
+
+    return d->instructions()[0].constant.idx;
+}
+
 /*!
     Return a pointer to the script's compile data, or null if there is no data.
  */
diff --git a/src/declarative/qml/qmlbasicscript_p.h b/src/declarative/qml/qmlbasicscript_p.h
index d096746..5ad7735 100644
--- a/src/declarative/qml/qmlbasicscript_p.h
+++ b/src/declarative/qml/qmlbasicscript_p.h
@@ -101,6 +101,8 @@ public:
     bool isSingleIdFetch() const;
     int singleIdFetchIndex() const;
 
+    bool isSingleContextProperty() const;
+    int singleContextPropertyIndex() const;
 private:
     int flags;
     QmlBasicScriptPrivate *d;
diff --git a/src/declarative/qml/qmlbindingoptimizations.cpp b/src/declarative/qml/qmlbindingoptimizations.cpp
index 235c034..a10b1e3 100644
--- a/src/declarative/qml/qmlbindingoptimizations.cpp
+++ b/src/declarative/qml/qmlbindingoptimizations.cpp
@@ -44,17 +44,27 @@
 
 QT_BEGIN_NAMESPACE
 
+/*
+    The QmlBinding_Id optimization handles expressions of the type:
 
-QmlBindingIdOptimization::QmlBindingIdOptimization(QObject *object, 
-                                                   int propertyIdx,
-                                                   QmlContext *context, 
-                                                   int id)
+        property: id
+
+    where id is a local context id, and property is an object property.  
+    Coercian between id and property must be checked outside the QmlBinding_Id -
+    it assumes that they coerce successfully.
+
+    The QmlBinding_Id class avoids any signal slot connections, through the
+    special "bindings" linked list maintained in the 
+    QmlContextPrivate::ContextGuard instance for each id object.
+*/
+QmlBinding_Id::QmlBinding_Id(QObject *object, int propertyIdx,
+                             QmlContext *context, int id)
 : m_prev(0), m_next(0), m_object(object), m_propertyIdx(propertyIdx), m_id(id)
 {
     QmlAbstractExpression::setContext(context);
 }
 
-void QmlBindingIdOptimization::setEnabled(bool e)
+void QmlBinding_Id::setEnabled(bool e)
 {
     if (e) {
         addToObject(m_object);
@@ -64,12 +74,12 @@ void QmlBindingIdOptimization::setEnabled(bool e)
     }
 }
 
-int QmlBindingIdOptimization::propertyIndex()
+int QmlBinding_Id::propertyIndex()
 {
     return m_propertyIdx;
 }
 
-void QmlBindingIdOptimization::update()
+void QmlBinding_Id::update()
 {
     QmlContextPrivate *ctxtPriv = 
         static_cast<QmlContextPrivate *>(QObjectPrivate::get(context()));
@@ -91,7 +101,7 @@ void QmlBindingIdOptimization::update()
     } 
 }
 
-void QmlBindingIdOptimization::reset()
+void QmlBinding_Id::reset()
 {
     if (m_prev) {
         *m_prev = m_next;
@@ -106,4 +116,70 @@ void QmlBindingIdOptimization::reset()
                           m_propertyIdx, a);
 }
 
+/*
+    The QmlBinding_ObjectProperty optimization handles expressions of the type:
+
+        property: objectProperty
+
+    where both property and objectProperty are object properties on the target
+    object.  Coercian between the two must be checked outside the 
+    QmlBinding_ObjectProperty - it assumes that they coerce successfully.
+
+    Due to dot properties, property does not have to be on the same object as 
+    objectProperty.  For example:
+
+        anchors.fill: parent
+*/
+QmlBinding_ObjProperty::QmlBinding_ObjProperty(QObject *object, int propertyIdx,
+                                               QObject *context, int contextIdx,
+                                               int notifyIdx)
+: m_enabled(false), m_object(object), m_propertyIdx(propertyIdx), 
+  m_context(context), m_contextIdx(contextIdx), m_notifyIdx(notifyIdx)
+{
+}
+
+void QmlBinding_ObjProperty::setEnabled(bool e)
+{
+    m_enabled = e;
+    if (e) {
+        addToObject(m_object);
+        update();
+    } else {
+        removeFromObject();
+    }
+}
+
+int QmlBinding_ObjProperty::propertyIndex()
+{
+    return m_propertyIdx;
+}
+
+void QmlBinding_ObjProperty::update()
+{
+    if (!m_enabled)
+        return;
+
+    QObject *value = 0;
+    void *a[] = { &value, 0 };
+
+    // Read
+    QMetaObject::metacall(m_context, QMetaObject::ReadProperty, 
+                          m_contextIdx, a);
+
+    // Write
+    QMetaObject::metacall(m_object, QMetaObject::WriteProperty, 
+                          m_propertyIdx, a);
+
+    // Connect notify if needed.  Only need to connect once, so we set
+    // m_notifyIdx back to -1 afterwards
+    static int slotIdx = -1;
+    if (m_notifyIdx != -1) {
+        if (slotIdx == -1) 
+            slotIdx = QmlBinding_ObjProperty::staticMetaObject.indexOfMethod("update()");
+
+        QMetaObject::connect(m_context, m_notifyIdx, this, slotIdx);
+        m_notifyIdx = -1;
+    }
+}
+
 QT_END_NAMESPACE
diff --git a/src/declarative/qml/qmlbindingoptimizations_p.h b/src/declarative/qml/qmlbindingoptimizations_p.h
index f50972d..2d2ffec 100644
--- a/src/declarative/qml/qmlbindingoptimizations_p.h
+++ b/src/declarative/qml/qmlbindingoptimizations_p.h
@@ -60,11 +60,11 @@ QT_BEGIN_HEADER
 
 QT_BEGIN_NAMESPACE
 
-class QmlBindingIdOptimization : public QmlAbstractExpression, 
-                                 public QmlAbstractBinding
+class QmlBinding_Id : public QmlAbstractExpression, 
+                      public QmlAbstractBinding
 {
 public:
-    QmlBindingIdOptimization(QObject *object, int propertyIdx,
+    QmlBinding_Id(QObject *object, int propertyIdx,
                              QmlContext *context, int id);
 
     // Inherited from QmlAbstractBinding
@@ -75,14 +75,39 @@ public:
     void reset();
 
 private:
-    QmlBindingIdOptimization **m_prev;
-    QmlBindingIdOptimization  *m_next;
+    QmlBinding_Id **m_prev;
+    QmlBinding_Id  *m_next;
 
     QObject *m_object;
     int m_propertyIdx;
     int m_id;
 };
 
+class QmlBinding_ObjProperty : public QObject,
+                               public QmlAbstractExpression,
+                               public QmlAbstractBinding
+{
+    Q_OBJECT
+public:
+    QmlBinding_ObjProperty(QObject *object, int propertyIdx,
+                           QObject *context, int contextIdx, int notifyIdx);
+
+    // Inherited from QmlAbstractBinding
+    virtual void setEnabled(bool);
+    virtual int propertyIndex();
+
+private slots:
+    virtual void update();
+
+private:
+    bool m_enabled;
+    QObject *m_object;
+    int m_propertyIdx;
+    QObject *m_context;
+    int m_contextIdx;
+    int m_notifyIdx;
+};
+
 QT_END_NAMESPACE
 
 QT_END_HEADER
diff --git a/src/declarative/qml/qmlcompiler.cpp b/src/declarative/qml/qmlcompiler.cpp
index 7c0964b..75ed94b 100644
--- a/src/declarative/qml/qmlcompiler.cpp
+++ b/src/declarative/qml/qmlcompiler.cpp
@@ -2069,6 +2069,7 @@ void QmlCompiler::genBindingAssignment(QmlParser::Value *binding,
     QmlBasicScript bs;
     if (ref.isBasicScript) 
         bs.load(ref.compiledData.constData() + sizeof(quint32));
+
     if (bs.isSingleIdFetch()) {
         int idIndex = bs.singleIdFetchIndex();
         QmlParser::Object *idObj = compileState.idIndexes.value(idIndex);
@@ -2079,9 +2080,26 @@ void QmlCompiler::genBindingAssignment(QmlParser::Value *binding,
             output->bytecode << store;
             return;
         }
+    } else if (bs.isSingleContextProperty()) {
+        int propIndex = bs.singleContextPropertyIndex();
+
+        QMetaProperty p = 
+            ref.bindingContext.object->metaObject()->property(propIndex);
+        if ((p.notifySignalIndex() != -1 || p.isConstant()) && 
+            canCoerce(prop->type, p.userType())) {
+
+            store.type = QmlInstruction::StoreObjPropBinding;
+            store.assignObjPropBinding.property = prop->index;
+            store.assignObjPropBinding.contextIdx = propIndex;
+            store.assignObjPropBinding.context = ref.bindingContext.stack;
+            store.assignObjPropBinding.notifyIdx = p.notifySignalIndex();
+
+            output->bytecode << store;
+            return;
+        }
     }
         
-    store.type = QmlInstruction::StoreCompiledBinding;
+    store.type = QmlInstruction::StoreBinding;
     store.assignBinding.value = output->indexForByteArray(ref.compiledData);
     store.assignBinding.context = ref.bindingContext.stack;
     store.assignBinding.owner = ref.bindingContext.owner;
@@ -2157,8 +2175,7 @@ bool QmlCompiler::completeComponentBuild()
 */
 bool QmlCompiler::canCoerce(int to, QmlParser::Object *from)
 {
-    const QMetaObject *toMo =
-        QmlMetaType::rawMetaObjectForType(to);
+    const QMetaObject *toMo = QmlMetaType::rawMetaObjectForType(to);
     const QMetaObject *fromMo = from->metaObject();
 
     while (fromMo) {
@@ -2169,6 +2186,23 @@ bool QmlCompiler::canCoerce(int to, QmlParser::Object *from)
     return false;
 }
 
+/*!
+    Returns true if from can be assigned to a (QObject) property of type
+    to.
+*/
+bool QmlCompiler::canCoerce(int to, int from)
+{
+    const QMetaObject *toMo = QmlMetaType::rawMetaObjectForType(to);
+    const QMetaObject *fromMo = QmlMetaType::rawMetaObjectForType(from);
+
+    while (fromMo) {
+        if (fromMo == toMo)
+            return true;
+        fromMo = fromMo->superClass();
+    }
+    return false;
+}
+
 QmlType *QmlCompiler::toQmlType(QmlParser::Object *from)
 {
     // ### Optimize
diff --git a/src/declarative/qml/qmlcompiler_p.h b/src/declarative/qml/qmlcompiler_p.h
index 3d79e32..4f56169 100644
--- a/src/declarative/qml/qmlcompiler_p.h
+++ b/src/declarative/qml/qmlcompiler_p.h
@@ -226,6 +226,7 @@ private:
 
     static int findSignalByName(const QMetaObject *, const QByteArray &name);
     static bool canCoerce(int to, QmlParser::Object *from);
+    static bool canCoerce(int to, int from);
     static QmlType *toQmlType(QmlParser::Object *from);
 
     QStringList deferredProperties(QmlParser::Object *);
diff --git a/src/declarative/qml/qmlcontext_p.h b/src/declarative/qml/qmlcontext_p.h
index b5479d9..84d990c 100644
--- a/src/declarative/qml/qmlcontext_p.h
+++ b/src/declarative/qml/qmlcontext_p.h
@@ -69,7 +69,7 @@ class QmlEngine;
 class QmlExpression;
 class QmlExpressionPrivate;
 class QmlAbstractExpression;
-class QmlBindingIdOptimization;
+class QmlBinding_Id;
 
 class QmlContextPrivate : public QObjectPrivate
 {
@@ -114,7 +114,7 @@ public:
     {
         ContextGuard() : priv(0), bindings(0) {}
         QmlContextPrivate *priv;
-        QmlBindingIdOptimization *bindings;
+        QmlBinding_Id *bindings;
         ContextGuard &operator=(QObject *obj) {
             (QGuard<QObject>&)*this = obj; return *this;
         }
diff --git a/src/declarative/qml/qmlinstruction.cpp b/src/declarative/qml/qmlinstruction.cpp
index 889a057..fd912ac 100644
--- a/src/declarative/qml/qmlinstruction.cpp
+++ b/src/declarative/qml/qmlinstruction.cpp
@@ -140,7 +140,7 @@ void QmlCompiledData::dump(QmlInstruction *instr, int idx)
     case QmlInstruction::AssignCustomType:
         qWarning() << idx << "\t" << line << "\t" << "ASSIGN_CUSTOMTYPE\t\t" << instr->assignCustomType.propertyIndex << "\t" << instr->assignCustomType.valueIndex;
         break;
-    case QmlInstruction::StoreCompiledBinding:
+    case QmlInstruction::StoreBinding:
         qWarning() << idx << "\t" << line << "\t" << "STORE_COMPILED_BINDING\t" << instr->assignBinding.property << "\t" << instr->assignBinding.value << "\t\t" << instr->assignBinding.context;
         break;
     case QmlInstruction::StoreValueSource:
diff --git a/src/declarative/qml/qmlinstruction_p.h b/src/declarative/qml/qmlinstruction_p.h
index 16bc8cf..7f3498f 100644
--- a/src/declarative/qml/qmlinstruction_p.h
+++ b/src/declarative/qml/qmlinstruction_p.h
@@ -122,10 +122,11 @@ public:
         // Unresolved single assignment
         //
         AssignSignalObject,       /* assignSignalObject */
-        AssignCustomType,          /* assignCustomType */
+        AssignCustomType,         /* assignCustomType */
 
-        StoreCompiledBinding,     /* assignBinding */
+        StoreBinding,             /* assignBinding */
         StoreIdOptBinding,        /* assignIdOptBinding */
+        StoreObjPropBinding,      /* assignObjPropBinding */
         StoreValueSource,         /* assignValueSource */
 
         BeginObject,              /* begin */
@@ -194,6 +195,12 @@ public:
         } assignIdOptBinding;
         struct {
             int property;
+            int contextIdx;
+            short context;
+            short notifyIdx;
+        } assignObjPropBinding;
+        struct {
+            int property;
         } fetch;
         struct {
             int property;
diff --git a/src/declarative/qml/qmlvme.cpp b/src/declarative/qml/qmlvme.cpp
index dccf5c4..fdfeddc 100644
--- a/src/declarative/qml/qmlvme.cpp
+++ b/src/declarative/qml/qmlvme.cpp
@@ -529,7 +529,7 @@ QObject *QmlVME::run(QStack<QObject *> &stack, QmlContext *ctxt, QmlCompiledData
             }
             break;
 
-        case QmlInstruction::StoreCompiledBinding:
+        case QmlInstruction::StoreBinding:
             {
                 QObject *target = 
                     stack.at(stack.count() - 1 - instr.assignBinding.owner);
@@ -554,14 +554,30 @@ QObject *QmlVME::run(QStack<QObject *> &stack, QmlContext *ctxt, QmlCompiledData
             {
                 QObject *target = stack.top();
 
-                QmlBindingIdOptimization *bind = 
-                    new QmlBindingIdOptimization(target, instr.assignIdOptBinding.property, ctxt, instr.assignIdOptBinding.id);
+                QmlBinding_Id *bind = 
+                    new QmlBinding_Id(target, instr.assignIdOptBinding.property,
+                                      ctxt, instr.assignIdOptBinding.id);
                 bindValues.append(bind);
                 // ### Need a mePtr
                 bind->addToObject(target);
             } 
             break;
 
+        case QmlInstruction::StoreObjPropBinding:
+            {
+                QObject *target = stack.top();
+                QObject *context = 
+                    stack.at(stack.count() - 1 - instr.assignObjPropBinding.context);
+
+                QmlBinding_ObjProperty *bind =
+                    new QmlBinding_ObjProperty(target, instr.assignObjPropBinding.property, context, instr.assignObjPropBinding.contextIdx, instr.assignObjPropBinding.notifyIdx);
+
+                bindValues.append(bind);
+                // ### Need a mePtr
+                bind->addToObject(target);
+            }
+            break;
+
         case QmlInstruction::StoreValueSource:
             {
                 QmlPropertyValueSource *vs =