11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
  26 #define SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
  27 
  28 #include "gc/shenandoah/shenandoahAsserts.hpp"
  29 #include "gc/shenandoah/shenandoahForwarding.hpp"
  30 #include "oops/markWord.inline.hpp"

  31 
  32 inline HeapWord* ShenandoahForwarding::get_forwardee_raw(oop obj) {
  33   shenandoah_assert_in_heap(NULL, obj);
  34   return get_forwardee_raw_unchecked(obj);
  35 }
  36 
  37 inline HeapWord* ShenandoahForwarding::get_forwardee_raw_unchecked(oop obj) {




  38   markWord mark = obj->mark_raw();
  39   if (mark.is_marked()) {
  40     return (HeapWord*) mark.clear_lock_bits().to_pointer();
  41   } else {



  42     return cast_from_oop<HeapWord*>(obj);














  43   }
  44 }
  45 
  46 inline oop ShenandoahForwarding::get_forwardee(oop obj) {
  47   shenandoah_assert_correct(NULL, obj);
  48   return oop(get_forwardee_raw_unchecked(obj));
  49 }
  50 
  51 inline bool ShenandoahForwarding::is_forwarded(oop obj) {
  52   return obj->mark_raw().is_marked();
  53 }
  54 
  55 inline oop ShenandoahForwarding::try_update_forwardee(oop obj, oop update) {
  56   markWord old_mark = obj->mark_raw();
  57   if (old_mark.is_marked()) {
  58     return oop(old_mark.clear_lock_bits().to_pointer());
  59   }
  60 
  61   markWord new_mark = markWord::encode_pointer_as_mark(update);
  62   markWord prev_mark = obj->cas_set_mark_raw(new_mark, old_mark);

  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
  26 #define SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
  27 
  28 #include "gc/shenandoah/shenandoahAsserts.hpp"
  29 #include "gc/shenandoah/shenandoahForwarding.hpp"
  30 #include "oops/markWord.inline.hpp"
  31 #include "runtime/thread.hpp"
  32 
  33 inline HeapWord* ShenandoahForwarding::get_forwardee_raw(oop obj) {
  34   shenandoah_assert_in_heap(NULL, obj);
  35   return get_forwardee_raw_unchecked(obj);
  36 }
  37 
  38 inline HeapWord* ShenandoahForwarding::get_forwardee_raw_unchecked(oop obj) {
  39   // JVMTI and JFR code use mark words for marking objects for their needs.
  40   // On this path, we can encounter the "marked" object, but with NULL
  41   // fwdptr. That object is still not forwarded, and we need to return
  42   // the object itself.
  43   markWord mark = obj->mark_raw();
  44   if (mark.is_marked()) {
  45     HeapWord* fwdptr = (HeapWord*) mark.clear_lock_bits().to_pointer();
  46     if (fwdptr != NULL) {
  47       return fwdptr;
  48     }
  49   }
  50   return cast_from_oop<HeapWord*>(obj);
  51 }
  52 
  53 inline oop ShenandoahForwarding::get_forwardee_mutator(oop obj) {
  54   // Same as above, but mutator thread cannot ever see NULL forwardee.
  55   shenandoah_assert_correct(NULL, obj);
  56   assert(Thread::current()->is_Java_thread(), "Must be a mutator thread");
  57 
  58   markWord mark = obj->mark_raw();
  59   if (mark.is_marked()) {
  60     HeapWord* fwdptr = (HeapWord*) mark.clear_lock_bits().to_pointer();
  61     assert(fwdptr != NULL, "Forwarding pointer is never null here");
  62     return cast_to_oop(fwdptr);
  63   } else {
  64     return obj;
  65   }
  66 }
  67 
  68 inline oop ShenandoahForwarding::get_forwardee(oop obj) {
  69   shenandoah_assert_correct(NULL, obj);
  70   return oop(get_forwardee_raw_unchecked(obj));
  71 }
  72 
  73 inline bool ShenandoahForwarding::is_forwarded(oop obj) {
  74   return obj->mark_raw().is_marked();
  75 }
  76 
  77 inline oop ShenandoahForwarding::try_update_forwardee(oop obj, oop update) {
  78   markWord old_mark = obj->mark_raw();
  79   if (old_mark.is_marked()) {
  80     return oop(old_mark.clear_lock_bits().to_pointer());
  81   }
  82 
  83   markWord new_mark = markWord::encode_pointer_as_mark(update);
  84   markWord prev_mark = obj->cas_set_mark_raw(new_mark, old_mark);