Don't flush code for generator functions.

src/objects-visiting-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 548 matching lines @@
   // Only flush code for functions.
   if (shared_info->code()->kind() != Code::FUNCTION) {
     return false;
   }
 
   // Function must be lazy compilable.
   if (!shared_info->allows_lazy_compilation()) {
     return false;
   }
 
+  // We do not (yet?) flush code for generator functions, because we don't know
+  // if there are still live activations (generator objects) on the heap.
+  if (shared_info->is_generator()) {
+    return false;
+  }
+
   // If this is a full script wrapped in a function we do no flush the code.
   if (shared_info->is_toplevel()) {
     return false;
   }
 
   // If this is a native function we do not flush the code because %SetCode
   // breaks the one-to-one relation between SharedFunctionInfo and Code.
   if (shared_info->native()) {
     return false;
   }
@@ skipping 146 matching lines @@
   RelocIterator it(this, mode_mask);
   for (; !it.done(); it.next()) {
     it.rinfo()->template Visit<StaticVisitor>(heap);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_VISITING_INL_H_