/*

 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

#include "precompiled.hpp"

#include "classfile/javaClasses.hpp"

#include "classfile/systemDictionary.hpp"

#include "oops/instanceRefKlass.inline.hpp"

#include "oops/oop.inline.hpp"

void InstanceRefKlass::update_nonstatic_oop_maps(Klass* k) {

  // Clear the nonstatic oop-map entries corresponding to referent

  // and nextPending field.  They are treated specially by the

  // garbage collector.

  // The discovered field is used only by the garbage collector

  // and is also treated specially.

  InstanceKlass* ik = InstanceKlass::cast(k);

  // Check that we have the right class

  debug_only(static bool first_time = true);

  assert(k == SystemDictionary::Reference_klass() && first_time,

         "Invalid update of maps");

  debug_only(first_time = false);

  assert(ik->nonstatic_oop_map_count() == 1, "just checking");

  OopMapBlock* map = ik->start_of_nonstatic_oop_maps();

  // Check that the current map is (2,4) - currently points at field with

  // offset 2 (words) and has 4 map entries.

  debug_only(int offset = java_lang_ref_Reference::referent_offset);

  debug_only(unsigned int count = ((java_lang_ref_Reference::discovered_offset -

    java_lang_ref_Reference::referent_offset)/heapOopSize) + 1);

  if (UseSharedSpaces) {

    assert(map->offset() == java_lang_ref_Reference::queue_offset &&

           map->count() == 1, "just checking");

  } else {

    assert(map->offset() == offset && map->count() == count,

           "just checking");

    // Update map to (3,1) - point to offset of 3 (words) with 1 map entry.

    map->set_offset(java_lang_ref_Reference::queue_offset);

    map->set_count(1);

  }

}

// Verification

void InstanceRefKlass::oop_verify_on(oop obj, outputStream* st) {

  InstanceKlass::oop_verify_on(obj, st);

  // Verify referent field

  oop referent = java_lang_ref_Reference::referent(obj);

  if (referent != NULL) {

  }

  // Verify next field

  oop next = java_lang_ref_Reference::next(obj);

  if (next != NULL) {

    guarantee(next->is_instance(), "next field should be an instance");

    guarantee(InstanceKlass::cast(next->klass())->is_reference_instance_klass(), "next field verify failed");

  }

}