src/hotspot/share/oops/oop.inline.hpp

*** 80,94 ****
  markWord oopDesc::cas_set_mark_raw(markWord new_mark, markWord old_mark, atomic_memory_order order) {
    return Atomic::cmpxchg(new_mark, &_mark, old_mark, order);
  }
  
  void oopDesc::init_mark() {
!   set_mark(markWord::prototype_for_object(this));
  }
  
  void oopDesc::init_mark_raw() {
!   set_mark_raw(markWord::prototype_for_object(this));
  }
  
  Klass* oopDesc::klass() const {
    if (UseCompressedClassPointers) {
      return CompressedKlassPointers::decode_not_null(_metadata._compressed_klass);
--- 80,94 ----
  markWord oopDesc::cas_set_mark_raw(markWord new_mark, markWord old_mark, atomic_memory_order order) {
    return Atomic::cmpxchg(new_mark, &_mark, old_mark, order);
  }
  
  void oopDesc::init_mark() {
!   set_mark(markWord::prototype_for_klass(klass()));
  }
  
  void oopDesc::init_mark_raw() {
!   set_mark_raw(markWord::prototype_for_klass(klass()));
  }
  
  Klass* oopDesc::klass() const {
    if (UseCompressedClassPointers) {
      return CompressedKlassPointers::decode_not_null(_metadata._compressed_klass);
*** 481,486 ****
--- 481,516 ----
  
  void oopDesc::set_displaced_mark_raw(markWord m) {
    mark_raw().set_displaced_mark_helper(m);
  }
  
+ // Supports deferred calling of obj->klass().
+ class DeferredObjectToKlass {
+   const oopDesc* _obj;
+ 
+ public:
+   DeferredObjectToKlass(const oopDesc* obj) : _obj(obj) {}
+ 
+   // Implicitly convertible to const Klass*.
+   operator const Klass*() const {
+     return _obj->klass();
+   }
+ };
+ 
+ bool oopDesc::mark_must_be_preserved() const {
+   return mark_must_be_preserved(mark_raw());
+ }
+ 
+ bool oopDesc::mark_must_be_preserved(markWord m) const {
+   // There's a circular dependency between oop.inline.hpp and
+   // markWord.inline.hpp because markWord::must_be_preserved wants to call
+   // oopDesc::klass(). This could be solved by calling klass() here. However,
+   // not all paths inside must_be_preserved calls klass(). Defer the call until
+   // the klass is actually needed.
+   return m.must_be_preserved(DeferredObjectToKlass(this));
+ }
+ 
+ bool oopDesc::mark_must_be_preserved_for_promotion_failure(markWord m) const {
+   return m.must_be_preserved_for_promotion_failure(DeferredObjectToKlass(this));
+ }
+ 
  #endif // SHARE_OOPS_OOP_INLINE_HPP