view hotspot/src/share/vm/gc/g1/g1ConcurrentMarkObjArrayProcessor.hpp @ 46328:6061df52d610

8168467: Use TaskEntry as task mark queue elements Summary: Change the mark stack to use TaskEntry queue elements to improve type safety instead of casting around raw pointers. Reviewed-by: kbarrett, sangheki
author tschatzl
date Wed, 15 Mar 2017 11:44:46 +0100
parents a9611bab7578
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 * published by the Free Software Foundation.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "oops/oopsHierarchy.hpp"
#include "memory/allocation.hpp"

class G1CMTask;

// Helper class to mark through large objArrays during marking in an efficient way.
// Instead of pushing large object arrays, we push continuations onto the
// mark stack. These continuations are identified by having their LSB set.
// This allows incremental processing of large objects.
class G1CMObjArrayProcessor VALUE_OBJ_CLASS_SPEC {
  // Reference to the task for doing the actual work.
  G1CMTask* _task;

  // Push the continuation at the given address onto the mark stack.
  void push_array_slice(HeapWord* addr);

  // Process (apply the closure) on the given continuation of the given objArray.
  size_t process_array_slice(objArrayOop const obj, HeapWord* start_from, size_t remaining);
  static bool should_be_sliced(oop obj);

  G1CMObjArrayProcessor(G1CMTask* task) : _task(task) {

  // Process the given continuation. Returns the number of words scanned.
  size_t process_slice(HeapWord* slice);
  // Start processing the given objArrayOop by scanning the header and pushing its
  // continuation.
  size_t process_obj(oop obj);