Make every member of a Heap object aware of its offset inside the object

This will allow adding a write barrier to those fields with manageable
effort.

Change-Id: I7d06d7ffccbcefe66e2524c64c962353c91c2766
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

6 files changed, 11 insertions, 3 deletions

diff --git a/src/qml/jsruntime/qv4context_p.h b/src/qml/jsruntime/qv4context_p.h
index ccea1dbc80..f544821729 100644
--- a/src/qml/jsruntime/qv4context_p.h
+++ b/src/qml/jsruntime/qv4context_p.h
@@ -171,7 +171,7 @@ V4_ASSERT_IS_TRIVIAL(GlobalContext)
 
 #define CatchContextMembers(class, Member) \
     Member(class, Pointer, String *, exceptionVarName) \
-    Member(class, Value, Value, exceptionValue)
+    Member(class, HeapValue, HeapValue, exceptionValue)
 
 DECLARE_HEAP_OBJECT(CatchContext, ExecutionContext) {
     DECLARE_MARK_TABLE(CatchContext);
diff --git a/src/qml/jsruntime/qv4functionobject_p.h b/src/qml/jsruntime/qv4functionobject_p.h
index 1fc40e6ff6..c7dac7d3e5 100644
--- a/src/qml/jsruntime/qv4functionobject_p.h
+++ b/src/qml/jsruntime/qv4functionobject_p.h
@@ -123,7 +123,7 @@ struct ScriptFunction : FunctionObject {
 
 #define BoundFunctionMembers(class, Member) \
     Member(class, Pointer, FunctionObject *, target) \
-    Member(class, Value, Value, boundThis) \
+    Member(class, HeapValue, HeapValue, boundThis) \
     Member(class, Pointer, MemberData *, boundArgs)
 
 DECLARE_HEAP_OBJECT(BoundFunction, FunctionObject) {
diff --git a/src/qml/jsruntime/qv4global_p.h b/src/qml/jsruntime/qv4global_p.h
index ea3e1d750e..cd8fb91f7a 100644
--- a/src/qml/jsruntime/qv4global_p.h
+++ b/src/qml/jsruntime/qv4global_p.h
@@ -199,6 +199,7 @@ struct ScriptFunction;
 struct InternalClass;
 struct Property;
 struct Value;
+template<size_t> struct HeapValue;
 template<size_t> struct ValueArray;
 struct Lookup;
 struct ArrayData;
diff --git a/src/qml/jsruntime/qv4object_p.h b/src/qml/jsruntime/qv4object_p.h
index 5b43710c03..63b132c2e6 100644
--- a/src/qml/jsruntime/qv4object_p.h
+++ b/src/qml/jsruntime/qv4object_p.h
@@ -82,6 +82,8 @@ DECLARE_HEAP_OBJECT(Object, Base) {
     Value *propertyData(uint index) { return memberData->values.v + index; }
 };
 
+Q_STATIC_ASSERT(Object::markTable == ((2 << 4) | (2 << 6) | (2 << 8)));
+
 }
 
 #define V4_OBJECT(superClass) \
diff --git a/src/qml/jsruntime/qv4regexpobject_p.h b/src/qml/jsruntime/qv4regexpobject_p.h
index b429524b71..c2eeb32b88 100644
--- a/src/qml/jsruntime/qv4regexpobject_p.h
+++ b/src/qml/jsruntime/qv4regexpobject_p.h
@@ -86,7 +86,7 @@ DECLARE_HEAP_OBJECT(RegExpObject, Object) {
 };
 
 #define RegExpCtorMembers(class, Member) \
-    Member(class, Value, Value, lastMatch) \
+    Member(class, HeapValue, HeapValue, lastMatch) \
     Member(class, Pointer, String *, lastInput) \
     Member(class, NoMark, int, lastMatchStart) \
     Member(class, NoMark, int, lastMatchEnd)
diff --git a/src/qml/jsruntime/qv4value_p.h b/src/qml/jsruntime/qv4value_p.h
index 771d28dce8..3d7776b736 100644
--- a/src/qml/jsruntime/qv4value_p.h
+++ b/src/qml/jsruntime/qv4value_p.h
@@ -709,6 +709,11 @@ inline unsigned int Value::toUInt32() const
 }
 
 template <size_t offset>
+struct HeapValue : Value {
+    HeapValue &operator = (const Value &other) { setRawValue(other.rawValue()); return *this; }
+};
+
+template <size_t offset>
 struct ValueArray {
     uint size;
     uint alloc;