Inline property data into the object

Append the part of the objects property data that is
known ad instantiation time to the object itself and
by that avoid creating a separate MemberData. Saves
some memory and should speed up object creation.

Currently implemented only for Object and ArrayObject.

Change-Id: I7693bf2f3a28fb718522398ebb94ac115e021fa4
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

4 files changed, 62 insertions, 26 deletions

diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index 58193fd68f..6c2705871a 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -301,7 +301,7 @@ ExecutionEngine::ExecutionEngine(EvalISelFactory *factory)
     jsObjects[ObjectProto] = memoryManager->alloc<ObjectPrototype>(emptyClass, (QV4::Object *)0);
 
     arrayClass = emptyClass->addMember(id_length(), Attr_NotConfigurable|Attr_NotEnumerable);
-    jsObjects[ArrayProto] = memoryManager->alloc<ArrayPrototype>(arrayClass, objectPrototype());
+    jsObjects[ArrayProto] = memoryManager->allocObject<ArrayPrototype>(arrayClass, objectPrototype());
 
     InternalClass *argsClass = emptyClass->addMember(id_length(), Attr_NotEnumerable);
     argumentsObjectClass = argsClass->addMember(id_callee(), Attr_Data|Attr_NotEnumerable);
@@ -540,16 +540,12 @@ ExecutionContext *ExecutionEngine::parentContext(ExecutionContext *context) cons
 
 Heap::Object *ExecutionEngine::newObject()
 {
-    Scope scope(this);
-    ScopedObject object(scope, memoryManager->alloc<Object>(this));
-    return object->d();
+    return memoryManager->allocObject<Object>(emptyClass, objectPrototype());
 }
 
 Heap::Object *ExecutionEngine::newObject(InternalClass *internalClass, QV4::Object *prototype)
 {
-    Scope scope(this);
-    ScopedObject object(scope, memoryManager->alloc<Object>(internalClass, prototype));
-    return object->d();
+    return memoryManager->allocObject<Object>(internalClass, prototype);
 }
 
 Heap::String *ExecutionEngine::newString(const QString &s)
@@ -587,7 +583,7 @@ Heap::Object *ExecutionEngine::newBooleanObject(bool b)
 Heap::ArrayObject *ExecutionEngine::newArrayObject(int count)
 {
     Scope scope(this);
-    ScopedArrayObject object(scope, memoryManager->alloc<ArrayObject>(this));
+    ScopedArrayObject object(scope, memoryManager->allocObject<ArrayObject>(arrayClass, arrayPrototype()));
 
     if (count) {
         if (count < 0x1000)
@@ -600,14 +596,14 @@ Heap::ArrayObject *ExecutionEngine::newArrayObject(int count)
 Heap::ArrayObject *ExecutionEngine::newArrayObject(const QStringList &list)
 {
     Scope scope(this);
-    ScopedArrayObject object(scope, memoryManager->alloc<ArrayObject>(this, list));
+    ScopedArrayObject object(scope, memoryManager->allocObject<ArrayObject>(arrayClass, arrayPrototype(), list));
     return object->d();
 }
 
-Heap::ArrayObject *ExecutionEngine::newArrayObject(InternalClass *ic, Object *prototype)
+Heap::ArrayObject *ExecutionEngine::newArrayObject(InternalClass *internalClass, Object *prototype)
 {
     Scope scope(this);
-    ScopedArrayObject object(scope, memoryManager->alloc<ArrayObject>(ic, prototype));
+    ScopedArrayObject object(scope, memoryManager->allocObject<ArrayObject>(internalClass, prototype));
     return object->d();
 }
 
diff --git a/src/qml/jsruntime/qv4internalclass.cpp b/src/qml/jsruntime/qv4internalclass.cpp
index bb2670036d..87987f7d50 100644
--- a/src/qml/jsruntime/qv4internalclass.cpp
+++ b/src/qml/jsruntime/qv4internalclass.cpp
@@ -136,12 +136,44 @@ InternalClass::InternalClass(const QV4::InternalClass &other)
 
 static void insertHoleIntoPropertyData(Object *object, int idx)
 {
-    memmove(object->d()->memberData->data + idx + 1, object->d()->memberData->data + idx, (object->internalClass()->size - idx - 1)*sizeof(Value));
+    int inlineSize = object->d()->inlineMemberSize;
+    int icSize = object->internalClass()->size;
+    int from = qMax(idx, inlineSize);
+    int to = from + 1;
+    if (from < icSize)
+        memmove(object->propertyData(to), object->propertyData(from), icSize - from - 1);
+    if (from == idx)
+        return;
+    if (inlineSize < icSize)
+        *object->propertyData(inlineSize) = *object->propertyData(inlineSize - 1);
+    from = idx;
+    to = from + 1;
+    if (from < inlineSize - 1)
+        memmove(object->propertyData(to), object->propertyData(from), inlineSize - from - 1);
 }
 
 static void removeFromPropertyData(Object *object, int idx, bool accessor = false)
 {
-    memmove(object->d()->memberData->data + idx, object->d()->memberData->data + idx + (accessor ? 2 : 1), (object->internalClass()->size - idx)*sizeof(Value));
+    int inlineSize = object->d()->inlineMemberSize;
+    int icSize = object->internalClass()->size;
+    int delta = (accessor ? 2 : 1);
+    int to = idx;
+    int from = to + delta;
+    if (from < inlineSize) {
+        memmove(object->propertyData(to), object->d()->propertyData(from), (inlineSize - from)*sizeof(Value));
+        to = inlineSize - delta;
+        from = inlineSize;
+    }
+    if (to < inlineSize && from < icSize) {
+        Q_ASSERT(from >= inlineSize);
+        memcpy(object->propertyData(to), object->d()->propertyData(from), (inlineSize - to)*sizeof(Value));
+        to = inlineSize;
+        from = inlineSize + delta;
+    }
+    if (from < icSize + delta) {
+        Q_ASSERT(to >= inlineSize && from > to);
+        memmove(object->propertyData(to), object->d()->propertyData(from), (icSize + delta - to)*sizeof(Value));
+    }
 }
 
 void InternalClass::changeMember(Object *object, String *string, PropertyAttributes data, uint *index)
diff --git a/src/qml/jsruntime/qv4object.cpp b/src/qml/jsruntime/qv4object.cpp
index 5f96e0d758..c8b703e198 100644
--- a/src/qml/jsruntime/qv4object.cpp
+++ b/src/qml/jsruntime/qv4object.cpp
@@ -213,6 +213,13 @@ void Object::markObjects(Heap::Base *that, ExecutionEngine *e)
 {
     Heap::Object *o = static_cast<Heap::Object *>(that);
 
+    if (o->inlineMemberSize) {
+        Value *v = o->propertyData(0);
+        Q_ASSERT(((char *)v) - ((char *)that) == sizeof(Heap::Object));
+        for (uint i = 0; i < o->inlineMemberSize; ++i)
+            v[i].mark(e);
+    }
+
     if (o->memberData)
         o->memberData->mark(e);
     if (o->arrayData)
@@ -224,7 +231,8 @@ void Object::markObjects(Heap::Base *that, ExecutionEngine *e)
 void Object::ensureMemberData()
 {
     QV4::InternalClass *ic = internalClass();
-    d()->memberData = MemberData::reallocate(ic->engine, d()->memberData, ic->size);
+    if (ic->size > d()->inlineMemberSize)
+        d()->memberData = MemberData::reallocate(ic->engine, d()->memberData, ic->size - d()->inlineMemberSize);
 }
 
 void Object::insertMember(String *s, const Property *p, PropertyAttributes attributes)
@@ -1156,11 +1164,11 @@ void Object::initSparseArray()
 
 DEFINE_OBJECT_VTABLE(ArrayObject);
 
-Heap::ArrayObject::ArrayObject(ExecutionEngine *engine, const QStringList &list)
-    : Heap::Object(engine->arrayClass, engine->arrayPrototype())
+Heap::ArrayObject::ArrayObject(const QStringList &list)
+    : Heap::Object()
 {
     init();
-    Scope scope(engine);
+    Scope scope(internalClass->engine);
     ScopedObject a(scope, this);
 
     // Converts a QStringList to JS.
@@ -1171,7 +1179,7 @@ Heap::ArrayObject::ArrayObject(ExecutionEngine *engine, const QStringList &list)
     a->arrayReserve(len);
     ScopedValue v(scope);
     for (int ii = 0; ii < len; ++ii)
-        a->arrayPut(ii, (v = engine->newString(list.at(ii))));
+        a->arrayPut(ii, (v = scope.engine->newString(list.at(ii))));
     a->setArrayLengthUnchecked(len);
 }
 
diff --git a/src/qml/jsruntime/qv4object_p.h b/src/qml/jsruntime/qv4object_p.h
index 943325ef03..636755808b 100644
--- a/src/qml/jsruntime/qv4object_p.h
+++ b/src/qml/jsruntime/qv4object_p.h
@@ -47,12 +47,15 @@ namespace QV4 {
 namespace Heap {
 
 struct Object : Base {
+    inline Object() {}
     inline Object(ExecutionEngine *engine);
     Object(InternalClass *internal, QV4::Object *prototype);
 
-    const Value *propertyData(uint index) const { return memberData->data + index; }
-    Value *propertyData(uint index) { return memberData->data + index; }
+    const Value *propertyData(uint index) const { if (index < inlineMemberSize) return reinterpret_cast<const Value *>(this) + inlineMemberOffset + index; return memberData->data + index - inlineMemberSize; }
+    Value *propertyData(uint index) { if (index < inlineMemberSize) return reinterpret_cast<Value *>(this) + inlineMemberOffset + index; return memberData->data + index - inlineMemberSize; }
 
+    uint inlineMemberOffset;
+    uint inlineMemberSize;
     InternalClass *internalClass;
     Pointer<Object> prototype;
     Pointer<MemberData> memberData;
@@ -371,13 +374,10 @@ struct ArrayObject : Object {
         LengthPropertyIndex = 0
     };
 
-    ArrayObject(ExecutionEngine *engine)
-        : Heap::Object(engine->arrayClass, engine->arrayPrototype())
-    { init(); }
-    ArrayObject(ExecutionEngine *engine, const QStringList &list);
-    ArrayObject(InternalClass *ic, QV4::Object *prototype)
-        : Heap::Object(ic, prototype)
+    ArrayObject()
+        : Heap::Object()
     { init(); }
+    ArrayObject(const QStringList &list);
     void init()
     { *propertyData(LengthPropertyIndex) = Primitive::fromInt32(0); }
 };