src/share/vm/oops/instanceRefKlass.cpp

*** 42,52 ****
    InstanceKlass* ik = InstanceKlass::cast(k);
  
    // Check that we have the right class
    debug_only(static bool first_time = true);
    assert(k == SystemDictionary::Reference_klass() && first_time,
!          "Invalid update of maps");
    debug_only(first_time = false);
    assert(ik->nonstatic_oop_map_count() == 1, "just checking");
  
    OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
  
--- 42,52 ----
    InstanceKlass* ik = InstanceKlass::cast(k);
  
    // Check that we have the right class
    debug_only(static bool first_time = true);
    assert(k == SystemDictionary::Reference_klass() && first_time,
!          "Invalid update of Reference maps");
    debug_only(first_time = false);
    assert(ik->nonstatic_oop_map_count() == 1, "just checking");
  
    OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
  
*** 67,76 ****
--- 67,105 ----
      map->set_offset(java_lang_ref_Reference::queue_offset);
      map->set_count(1);
    }
  }
  
+ void InstanceRefKlass::update_nonstatic_ephemeron_oop_maps(Klass* k) {
+     // Clear the nonstatic oop-map entry corresponding to value field.
+     // It is treated specially by the garbage collector.
+     InstanceKlass* ik = InstanceKlass::cast(k);
+ 
+     // Check that we have the right class
+     debug_only(static bool first_time = true);
+     assert(k == SystemDictionary::Ephemeron_klass() && first_time,
+             "Invalid update of Ephemeron maps");
+     debug_only(first_time = false);
+     assert(ik->nonstatic_oop_map_count() == 2, "just checking");
+ 
+     // skip 1st map as it's the copy of the augmented Reference's map
+     OopMapBlock* map = ik->start_of_nonstatic_oop_maps() + 1; 
+     
+     debug_only(int offset = java_lang_ref_Ephemeron::value_offset);
+ 
+     if (UseSharedSpaces) {
+         assert(map->offset() == offset && map->count() == 0,
+                 "just checking");
+     } else {
+         assert(map->offset() == offset && map->count() == 1,
+                 "just checking");
+ 
+         // Update map to have 0 oops.
+         map->set_count(0);
+     }
+ }
+ 
  
  // Verification
  
  void InstanceRefKlass::oop_verify_on(oop obj, outputStream* st) {
    InstanceKlass::oop_verify_on(obj, st);