Make object property lookup resolution virtual

This allows sub-classes of Object to have their own lookup resolution
and verification logic, instead of squeezing it all into qv4lookup.cpp.
The typical fallbacks are still in qv4lookup.cpp though.

Task-number: QTBUG-69898
Change-Id: I32a8884982b37e2065090666a7bf05b198f5b7fd
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/qml/jsruntime/qv4vtable_p.h b/src/qml/jsruntime/qv4vtable_p.h
index 4acefecdf5..aff1ae82d7 100644
--- a/src/qml/jsruntime/qv4vtable_p.h
+++ b/src/qml/jsruntime/qv4vtable_p.h
@@ -56,6 +56,8 @@ QT_BEGIN_NAMESPACE
 
 namespace QV4 {
 
+struct Lookup;
+
 struct OwnPropertyKeyIterator {
     virtual ~OwnPropertyKeyIterator() = 0;
     virtual PropertyKey next(const Object *o, Property *p = nullptr, PropertyAttributes *attrs = nullptr) = 0;
@@ -84,6 +86,9 @@ struct VTable
     typedef ReturnedValue (*Call)(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
     typedef ReturnedValue (*CallAsConstructor)(const FunctionObject *, const Value *argv, int argc, const Value *newTarget);
 
+    typedef ReturnedValue (*ResolveLookupGetter)(const Object *, ExecutionEngine *, Lookup *);
+    typedef bool (*ResolveLookupSetter)(Object *, ExecutionEngine *, Lookup *, const Value &);
+
     const VTable * const parent;
     quint32 inlinePropertyOffset : 16;
     quint32 nInlineProperties : 16;
@@ -118,6 +123,9 @@ struct VTable
 
     Call call;
     CallAsConstructor callAsConstructor;
+
+    ResolveLookupGetter resolveLookupGetter;
+    ResolveLookupSetter resolveLookupSetter;
 };
 
 
@@ -142,6 +150,9 @@ protected:
 
     static constexpr VTable::Call virtualCall = nullptr;
     static constexpr VTable::CallAsConstructor virtualCallAsConstructor = nullptr;
+
+    static constexpr VTable::ResolveLookupGetter virtualResolveLookupGetter = nullptr;
+    static constexpr VTable::ResolveLookupSetter virtualResolveLookupSetter = nullptr;
 };
 
 #define DEFINE_MANAGED_VTABLE_INT(classname, parentVTable) \
@@ -181,6 +192,9 @@ protected:
     \
     classname::virtualCall,                 \
     classname::virtualCallAsConstructor,    \
+    \
+    classname::virtualResolveLookupGetter,  \
+    classname::virtualResolveLookupSetter   \
 }
 
 #define DEFINE_MANAGED_VTABLE(classname) \