V4: Pass scope around as parameters inside the runtime.

The implementation of many (or all) runtime functions consist of first
creating a QV4::Scope, which saves and restores the JS stack pointer.
It also prevents tail-calls because of that restoring behavior. In many
cases it suffices to do that at the entry-point of the runtime.

The return value of a JS function call is now also stored in the scope.
Previously, all return values were stored in a ScopedValue, got loaded
on return, and immediately stored in another ScopedValue in the caller.
This resulted in a lot of stores, where now there is only one store
needed, and no extra ScopedValue for every function.

Change-Id: I13d80fc0ce72c5702ef1536d41d12f710c5914fa
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 2 insertions, 3 deletions

diff --git a/src/qml/qml/qqmljavascriptexpression_p.h b/src/qml/qml/qqmljavascriptexpression_p.h
index 94479f6c5e..4472a643ff 100644
--- a/src/qml/qml/qqmljavascriptexpression_p.h
+++ b/src/qml/qml/qqmljavascriptexpression_p.h
@@ -103,8 +103,7 @@ public:
     virtual QString expressionIdentifier() = 0;
     virtual void expressionChanged() = 0;
 
-    QV4::ReturnedValue evaluate(bool *isUndefined);
-    QV4::ReturnedValue evaluate(QV4::CallData *callData, bool *isUndefined);
+    void evaluate(QV4::CallData *callData, bool *isUndefined, QV4::Scope &scope);
 
     inline bool notifyOnValueChanged() const;
 
@@ -181,7 +180,7 @@ public:
     void captureProperty(QQmlNotifier *);
     void captureProperty(QObject *, int, int);
 
-    static void registerQmlDependencies(QV4::ExecutionEngine *engine, const QV4::CompiledData::Function *compiledFunction);
+    static void registerQmlDependencies(const QV4::CompiledData::Function *compiledFunction, const QV4::Scope &scope);
 
     QQmlEngine *engine;
     QQmlJavaScriptExpression *expression;