src/hotspot/share/gc/serial/defNewGeneration.cpp

@@ -868,11 +868,25 @@
    // of objs in young-gen so that no objs are marked (forwarded) when Full GC
    // starts. (The mark word is overloaded: `is_marked()` == `is_forwarded()`.)
    struct ResetForwardedMarkWord : ObjectClosure {
      void do_object(oop obj) override {
        if (obj->is_forwarded()) {
-         obj->init_mark();
+ #ifdef _LP64
+         if (UseCompactObjectHeaders) {
+           oop forwardee = obj->forwardee();
+           markWord header = forwardee->mark();
+           if (header.has_displaced_mark_helper()) {
+             header = header.displaced_mark_helper();
+           }
+           assert(UseCompressedClassPointers, "assume +UseCompressedClassPointers");
+           narrowKlass nklass = header.narrow_klass();
+           obj->set_mark(markWord::prototype().set_narrow_klass(nklass));
+         } else
+ #endif
+         {
+           obj->init_mark();
+         }
        }
      }
    } cl;
    eden()->object_iterate(&cl);
    from()->object_iterate(&cl);

@@ -892,11 +906,11 @@
    _preserved_marks_set.get()->push_if_necessary(old, old->mark());
  
    ContinuationGCSupport::transform_stack_chunk(old);
  
    // forward to self
-   old->forward_to(old);
+   old->forward_to_self();
  
    _promo_failure_scan_stack.push(old);
  
    if (!_promo_failure_drain_in_progress) {
      // prevent recursion in copy_to_survivor_space()