1 /*
   2  * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHPARTIALGC_INLINE_HPP
  25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHPARTIALGC_INLINE_HPP
  26 
  27 #include "gc/shenandoah/shenandoahAsserts.hpp"
  28 #include "gc/shenandoah/shenandoahPartialGC.hpp"
  29 
  30 template <class T, bool UPDATE_MATRIX>
  31 void ShenandoahPartialGC::process_oop(T* p, Thread* thread, ShenandoahObjToScanQueue* queue) {
  32   T o = RawAccess<>::oop_load(p);
  33   if (!CompressedOops::is_null(o)) {
  34     oop obj = CompressedOops::decode_not_null(o);
  35     if (_heap->in_collection_set(obj)) {
  36       oop forw = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
  37       if (oopDesc::unsafe_equals(obj, forw)) {
  38         bool evacuated = false;
  39         forw = _heap->evacuate_object(obj, thread, evacuated);
  40 
  41         // Only the thread that succeeded evacuating this object pushes it to its work queue.
  42         if (evacuated) {
  43           assert(oopDesc::is_oop(forw), "sanity");
  44           bool succeeded = queue->push(ShenandoahMarkTask(forw));
  45           assert(succeeded, "must succeed to push to task queue");
  46         }
  47       }
  48       assert(! oopDesc::unsafe_equals(obj, forw) || _heap->cancelled_concgc(), "must be evacuated");
  49       // Update reference.
  50       _heap->atomic_compare_exchange_oop(forw, p, obj);
  51       // TODO: No need to update matrix if other thread beat us.
  52       obj = forw; // For matrix update below.
  53     }
  54     if (UPDATE_MATRIX) {
  55       shenandoah_assert_not_forwarded_except(p, obj, _heap->cancelled_concgc());
  56       _matrix->set_connected(p, obj);
  57     }
  58   }
  59 }
  60 
  61 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHPARTIALGC_INLINE_HPP