Avoid marking on simple array data's

Speeds up things by 2-3%.

Change-Id: Ib17ab126cf91ce48a0ced7dd7b06c4f7f0a70a3b
Reviewed-by: Erik Verbruggen <erik.verbruggen@qt.io>

4 files changed, 27 insertions, 4 deletions

diff --git a/src/qml/jsruntime/qv4arraydata.cpp b/src/qml/jsruntime/qv4arraydata.cpp
index 0130dc0077..390840fb1e 100644
--- a/src/qml/jsruntime/qv4arraydata.cpp
+++ b/src/qml/jsruntime/qv4arraydata.cpp
@@ -111,6 +111,13 @@ static Q_ALWAYS_INLINE void storeValue(ReturnedValue *target, uint value)
     *target = v.asReturnedValue();
 }
 
+void Heap::ArrayData::markObjects(Heap::Base *base, MarkStack *stack)
+{
+    ArrayData *a = static_cast<ArrayData *>(base);
+    a->values.mark(stack);
+}
+
+
 void ArrayData::realloc(Object *o, Type newType, uint requested, bool enforceAttributes)
 {
     Scope scope(o->engine());
@@ -161,6 +168,8 @@ void ArrayData::realloc(Object *o, Type newType, uint requested, bool enforceAtt
     }
     newData->setAlloc(alloc);
     newData->setType(newType);
+    if (d)
+        newData->d()->needsMark = d->d()->needsMark;
     newData->setAttrs(enforceAttributes ? reinterpret_cast<PropertyAttributes *>(newData->d()->values.values + alloc) : 0);
     o->setArrayData(newData);
 
@@ -183,6 +192,8 @@ void ArrayData::realloc(Object *o, Type newType, uint requested, bool enforceAtt
         memcpy(newData->d()->values.values, d->d()->values.values + offset, sizeof(Value)*toCopy);
     }
 
+    if (newType != Heap::ArrayData::Simple)
+        newData->d()->needsMark = true;
     if (newType != Heap::ArrayData::Sparse)
         return;
 
diff --git a/src/qml/jsruntime/qv4arraydata_p.h b/src/qml/jsruntime/qv4arraydata_p.h
index 154fe5d150..db9db5a220 100644
--- a/src/qml/jsruntime/qv4arraydata_p.h
+++ b/src/qml/jsruntime/qv4arraydata_p.h
@@ -91,7 +91,8 @@ struct ArrayVTable
 namespace Heap {
 
 #define ArrayDataMembers(class, Member) \
-    Member(class, NoMark, uint, type) \
+    Member(class, NoMark, ushort, type) \
+    Member(class, NoMark, ushort, needsMark) \
     Member(class, NoMark, uint, offset) \
     Member(class, NoMark, PropertyAttributes *, attrs) \
     Member(class, NoMark, ReturnedValue, freeList) \
@@ -99,7 +100,7 @@ namespace Heap {
     Member(class, ValueArray, ValueArray, values)
 
 DECLARE_HEAP_OBJECT(ArrayData, Base) {
-    DECLARE_MARKOBJECTS(ArrayData);
+    static void markObjects(Heap::Base *base, MarkStack *stack);
 
     enum Type { Simple = 0, Complex = 1, Sparse = 2, Custom = 3 };
 
@@ -147,6 +148,8 @@ struct SimpleArrayData : public ArrayData {
     uint mappedIndex(uint index) const { index += offset; if (index >= values.alloc) index -= values.alloc; return index; }
     const Value &data(uint index) const { return values[mappedIndex(index)]; }
     void setData(EngineBase *e, uint index, Value newVal) {
+        if (newVal.isManaged())
+            needsMark = true;
         values.set(e, mappedIndex(index), newVal);
     }
 
diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index 049e4a117d..78c10eacc7 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -585,6 +585,12 @@ Heap::ArrayObject *ExecutionEngine::newArrayObject(const Value *values, int leng
         // this doesn't require a write barrier, things will be ok, when the new array data gets inserted into
         // the parent object
         memcpy(&d->values.values, values, length*sizeof(Value));
+        for (int i = 0; i < length; ++i) {
+            if (values[i].isManaged()) {
+                d->needsMark = true;
+                break;
+            }
+        }
         a->d()->arrayData.set(this, d);
         a->setArrayLengthUnchecked(length);
     }
diff --git a/src/qml/jsruntime/qv4object.cpp b/src/qml/jsruntime/qv4object.cpp
index 8fbcadfd4a..70f6341ac9 100644
--- a/src/qml/jsruntime/qv4object.cpp
+++ b/src/qml/jsruntime/qv4object.cpp
@@ -271,8 +271,11 @@ void Heap::Object::markObjects(Heap::Base *b, MarkStack *stack)
     Object *o = static_cast<Object *>(b);
     if (o->memberData)
         o->memberData->mark(stack);
-    if (o->arrayData)
-        o->arrayData->mark(stack);
+    if (o->arrayData) {
+        o->arrayData->setMarkBit();
+        if (o->arrayData->needsMark)
+            ArrayData::markObjects(o->arrayData, stack);
+    }
     uint nInline = o->vtable()->nInlineProperties;
     Value *v = reinterpret_cast<Value *>(o) + o->vtable()->inlinePropertyOffset;
     const Value *end = v + nInline;