view src/share/vm/oops/oop.pcgc.inline.hpp @ 1091:6aa7255741f3

6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa
author ysr
date Thu, 03 Dec 2009 15:01:57 -0800
parents d1605aabd0a1
children c18cbe5936b8
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/*
 * Copyright 2005-2008 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * 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.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

inline void oopDesc::update_contents(ParCompactionManager* cm) {
  // The klass field must be updated before anything else
  // can be done.
  DEBUG_ONLY(klassOopDesc* original_klass = klass());

  // Can the option to update and/or copy be moved up in the
  // call chain to avoid calling into here?

  if (PSParallelCompact::should_update_klass(klass())) {
    update_header();
    assert(klass()->is_klass(), "Not updated correctly");
  } else {
    assert(klass()->is_klass(), "Not updated");
  }

  Klass* new_klass = blueprint();
  if (!new_klass->oop_is_typeArray()) {
    // It might contain oops beyond the header, so take the virtual call.
    new_klass->oop_update_pointers(cm, this);
  }
  // Else skip it.  The typeArrayKlass in the header never needs scavenging.
}

inline void oopDesc::update_contents(ParCompactionManager* cm,
                                     HeapWord* begin_limit,
                                     HeapWord* end_limit) {
  // The klass field must be updated before anything else
  // can be done.
  debug_only(klassOopDesc* original_klass = klass());

  update_contents(cm, klass(), begin_limit, end_limit);
}

inline void oopDesc::update_contents(ParCompactionManager* cm,
                                     klassOop old_klass,
                                     HeapWord* begin_limit,
                                     HeapWord* end_limit) {

  klassOop updated_klass =
    PSParallelCompact::summary_data().calc_new_klass(old_klass);

  // Needs to be boundary aware for the 64 bit case
  // update_header();
  // The klass has moved.  Is the location of the klass
  // within the limits?
  if ((((HeapWord*)&_metadata._klass) >= begin_limit) &&
      (((HeapWord*)&_metadata._klass) < end_limit)) {
    set_klass(updated_klass);
  }

  Klass* klass = updated_klass->klass_part();
  if (!klass->oop_is_typeArray()) {
    // It might contain oops beyond the header, so take the virtual call.
    klass->oop_update_pointers(cm, this, begin_limit, end_limit);
  }
  // Else skip it.  The typeArrayKlass in the header never needs scavenging.
}

inline void oopDesc::follow_contents(ParCompactionManager* cm) {
  assert (PSParallelCompact::mark_bitmap()->is_marked(this),
    "should be marked");
  blueprint()->oop_follow_contents(cm, this);
}

// Used by parallel old GC.

inline void oopDesc::follow_header(ParCompactionManager* cm) {
  if (UseCompressedOops) {
    PSParallelCompact::mark_and_push(cm, compressed_klass_addr());
  } else {
    PSParallelCompact::mark_and_push(cm, klass_addr());
  }
}

inline oop oopDesc::forward_to_atomic(oop p) {
  assert(ParNewGeneration::is_legal_forward_ptr(p),
         "illegal forwarding pointer value.");
  markOop oldMark = mark();
  markOop forwardPtrMark = markOopDesc::encode_pointer_as_mark(p);
  markOop curMark;

  assert(forwardPtrMark->decode_pointer() == p, "encoding must be reversable");
  assert(sizeof(markOop) == sizeof(intptr_t), "CAS below requires this.");

  while (!is_forwarded()) {
    curMark = (markOop)Atomic::cmpxchg_ptr(forwardPtrMark, &_mark, oldMark);
    if (curMark == oldMark) {
      assert(is_forwarded(), "the CAS should have succeeded.");
      return NULL;
    }
    oldMark = curMark;
  }
  return forwardee();
}

inline void oopDesc::update_header() {
  if (UseCompressedOops) {
    PSParallelCompact::adjust_pointer(compressed_klass_addr());
  } else {
    PSParallelCompact::adjust_pointer(klass_addr());
  }
}

inline void oopDesc::update_header(HeapWord* beg_addr, HeapWord* end_addr) {
  if (UseCompressedOops) {
    PSParallelCompact::adjust_pointer(compressed_klass_addr(),
                                      beg_addr, end_addr);
  } else {
    PSParallelCompact::adjust_pointer(klass_addr(), beg_addr, end_addr);
  }
}