MM: Provide information about object types on sweep

Helps give an idea about what kind of garbage is being tossed away.
v8-bench shows no real change in performance outside "usual" variance, I
didn't benchmark QV4_MM_STATS=1 but I assume there will be some penalty
there.

Change-Id: Ida0c5917289891279d95fd47480bd4869b42b0e6
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/qml/memory/qv4mmdefs_p.h b/src/qml/memory/qv4mmdefs_p.h
index 9512722782..bf29b44a2c 100644
--- a/src/qml/memory/qv4mmdefs_p.h
+++ b/src/qml/memory/qv4mmdefs_p.h
@@ -61,6 +61,8 @@ namespace QV4 {
 
 struct MarkStack;
 
+typedef void(*ClassDestroyStatsCallback)(const char *);
+
 /*
  * Chunks are the basic structure containing GC managed objects.
  *
@@ -184,7 +186,7 @@ struct Chunk {
         return usedSlots;
     }
 
-    void sweep();
+    void sweep(ClassDestroyStatsCallback classCountPtr);
     void freeAll();
     void resetBlackBits();
     void collectGrayItems(QV4::MarkStack *markStack);