QML: Create a fast-path for QV4::WeakValue::set

And hint the compiler (with LTO) to never inline the slow path.

Change-Id: Idad15498bca457d3f1f063031ad1a08415e9b3db
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 22 insertions, 3 deletions

diff --git a/src/qml/jsruntime/qv4persistent_p.h b/src/qml/jsruntime/qv4persistent_p.h
index a0ade2068f..c1cd1f34df 100644
--- a/src/qml/jsruntime/qv4persistent_p.h
+++ b/src/qml/jsruntime/qv4persistent_p.h
@@ -154,9 +154,26 @@ public:
     WeakValue &operator=(const WeakValue &other);
     ~WeakValue();
 
-    void set(ExecutionEngine *engine, const Value &value);
-    void set(ExecutionEngine *engine, ReturnedValue value);
-    void set(ExecutionEngine *engine, Heap::Base *obj);
+    void set(ExecutionEngine *engine, const Value &value)
+    {
+        if (!val)
+            allocVal(engine);
+        *val = value;
+    }
+
+    void set(ExecutionEngine *engine, ReturnedValue value)
+    {
+        if (!val)
+            allocVal(engine);
+        *val = value;
+    }
+
+    void set(ExecutionEngine *engine, Heap::Base *obj)
+    {
+        if (!val)
+            allocVal(engine);
+        *val = obj;
+    }
 
     ReturnedValue value() const {
         return (val ? val->asReturnedValue() : Encode::undefined());
@@ -192,6 +209,8 @@ private:
     Value *val;
 
 private:
+    Q_NEVER_INLINE void allocVal(ExecutionEngine *engine);
+
     void free();
 };