Set the code age field of SharedFunctionInfo correctly.

src/mark-compact.cc

Index: src/mark-compact.cc
diff --git a/src/mark-compact.cc b/src/mark-compact.cc
index 09dcc310c2fa7792ed925c0755c011636d762f4e..74c077758b5fc81ae2a5f006966aff61b829dae9 100644
--- a/src/mark-compact.cc
+++ b/src/mark-compact.cc
@@ -1012,7 +1012,9 @@ class StaticMarkingVisitor : public StaticVisitorBase {
     MarkBit code_mark =
         Marking::MarkBitFrom(function->unchecked_code());
     if (code_mark.Get()) {
-      shared_info->set_code_age(0);
+      if (!Marking::MarkBitFrom(shared_info).Get()) {

[ulan, 2011/11/21 17:36:15]

Do not reset the code age if the shared info visitor already checked for
flushability and possibly updated the code age.

+        shared_info->set_code_age(0);
+      }
       return false;
     }
 
@@ -1030,7 +1032,6 @@ class StaticMarkingVisitor : public StaticVisitorBase {
     MarkBit code_mark =
         Marking::MarkBitFrom(shared_info->unchecked_code());
     if (code_mark.Get()) {
-      shared_info->set_code_age(0);

[ulan, 2011/11/21 17:36:15]

Do not reset the code age, the JSFunction visitor(s) could have checked for
flushability and possibly updated the code age.

       return false;
     }