src/hotspot/share/oops/oop.cpp

@@ -28,14 +28,16 @@
  #include "gc/shared/collectedHeap.inline.hpp"
  #include "gc/shared/gc_globals.hpp"
  #include "memory/resourceArea.hpp"
  #include "memory/universe.hpp"
  #include "oops/access.inline.hpp"
+ #include "oops/compressedKlass.inline.hpp"
  #include "oops/compressedOops.inline.hpp"
  #include "oops/oop.inline.hpp"
  #include "oops/verifyOopClosure.hpp"
  #include "runtime/handles.inline.hpp"
+ #include "runtime/interfaceSupport.inline.hpp"
  #include "runtime/thread.inline.hpp"
  #include "utilities/copy.hpp"
  #include "utilities/macros.hpp"
  
  void oopDesc::print_on(outputStream* st) const {

@@ -138,31 +140,19 @@
  bool oopDesc::is_instanceRef_noinline() const { return is_instanceRef(); }
  bool oopDesc::is_array_noinline()       const { return is_array();       }
  bool oopDesc::is_objArray_noinline()    const { return is_objArray();    }
  bool oopDesc::is_typeArray_noinline()   const { return is_typeArray();   }
  
- bool oopDesc::has_klass_gap() {
-   // Only has a klass gap when compressed class pointers are used.
-   return UseCompressedClassPointers;
- }
- 
- #if INCLUDE_CDS_JAVA_HEAP
- void oopDesc::set_narrow_klass(narrowKlass nk) {
-   assert(DumpSharedSpaces, "Used by CDS only. Do not abuse!");
-   assert(UseCompressedClassPointers, "must be");
-   _metadata._compressed_klass = nk;
- }
- #endif
- 
  void* oopDesc::load_klass_raw(oop obj) {
-   if (UseCompressedClassPointers) {
-     narrowKlass narrow_klass = obj->_metadata._compressed_klass;
-     if (narrow_klass == 0) return NULL;
-     return (void*)CompressedKlassPointers::decode_raw(narrow_klass);
-   } else {
-     return obj->_metadata._klass;
-   }
+   // TODO: Remove method altogether and replace with calls to obj->klass() ?
+   // OTOH, we may eventually get rid of locking in header, and then no
+   // longer have to deal with that anymore.
+ #ifdef _LP64
+   return obj->klass();
+ #else
+   return obj->_klass;
+ #endif
  }
  
  void* oopDesc::load_oop_raw(oop obj, int offset) {
    uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset;
    if (UseCompressedOops) {

@@ -172,10 +162,25 @@
    } else {
      return *(void**)addr;
    }
  }
  
+ #ifdef _LP64
+ JRT_LEAF(narrowKlass, oopDesc::load_nklass_runtime(oopDesc* o))
+   assert(o != NULL, "null-check");
+   oop obj = oop(o);
+   assert(oopDesc::is_oop(obj), "need a valid oop here: " PTR_FORMAT, p2i(o));
+   markWord header = obj->mark();
+   if (!header.is_neutral()) {
+     header = ObjectSynchronizer::stable_mark(obj);
+   }
+   assert(header.is_neutral(), "expect neutral header here");
+   narrowKlass nklass = header.narrow_klass();
+   return nklass;
+ JRT_END
+ #endif
+ 
  oop oopDesc::obj_field_acquire(int offset) const                      { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
  
  void oopDesc::obj_field_put_raw(int offset, oop value)                { RawAccess<>::oop_store_at(as_oop(), offset, value); }
  void oopDesc::release_obj_field_put(int offset, oop value)            { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); }
  void oopDesc::obj_field_put_volatile(int offset, oop value)           { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); }