src/hotspot/share/cds/regeneratedClasses.cpp

/*
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 * 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.
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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#include "cds/archiveBuilder.hpp"
#include "cds/regeneratedClasses.hpp"
#include "memory/universe.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/method.hpp"
#include "oops/oopHandle.inline.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/thread.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/resourceHash.hpp"

using RegeneratedObjTable = ResourceHashtable<address, address, 15889, AnyObj::C_HEAP, mtClassShared>;
static RegeneratedObjTable* _renegerated_objs = nullptr; // InstanceKlass* and Method*
static GrowableArrayCHeap<OopHandle, mtClassShared>* _regenerated_mirrors = nullptr;

// The regenerated Klass is not added to any class loader, so we need
// to keep its java_mirror alive to avoid class unloading.
void RegeneratedClasses::add_class(InstanceKlass* orig_klass, InstanceKlass* regen_klass) {
  MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
  if (_regenerated_mirrors == nullptr) {
    _regenerated_mirrors = new GrowableArrayCHeap<OopHandle, mtClassShared>(150);
  }
  _regenerated_mirrors->append(OopHandle(Universe::vm_global(), regen_klass->java_mirror()));

  if (_renegerated_objs == nullptr) {
    _renegerated_objs = new (mtClass)RegeneratedObjTable();
  }

  _renegerated_objs->put((address)orig_klass, (address)regen_klass);
  Array<Method*>* methods = orig_klass->methods();
  for (int i = 0; i < methods->length(); i++) {
    Method* orig_m = methods->at(i);
    Method* regen_m = regen_klass->find_method(orig_m->name(), orig_m->signature());
    if (regen_m == nullptr) {
      ResourceMark rm;
      log_warning(aot)("Method in original class is missing from regenerated class: " INTPTR_FORMAT " %s",
                       p2i(orig_m), orig_m->external_name());
    } else {
      _renegerated_objs->put((address)orig_m, (address)regen_m);
    }
  }
}

bool RegeneratedClasses::has_been_regenerated(address orig_obj) {
  if (_renegerated_objs == nullptr) {
    return false;
  } else {
    return _renegerated_objs->get(orig_obj) != nullptr;
  }
}

void RegeneratedClasses::record_regenerated_objects() {
  assert_locked_or_safepoint(DumpTimeTable_lock);
  if (_renegerated_objs != nullptr) {
    auto doit = [&] (address orig_obj, address regen_obj) {
      ArchiveBuilder::current()->record_regenerated_object(orig_obj, regen_obj);
    };
    _renegerated_objs->iterate_all(doit);
  }
}

void RegeneratedClasses::cleanup() {
  MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
  if (_regenerated_mirrors != nullptr) {
    for (int i = 0; i < _regenerated_mirrors->length(); i++) {
      _regenerated_mirrors->at(i).release(Universe::vm_global());
    }
    delete _regenerated_mirrors;
    _regenerated_mirrors = nullptr;
  }
  if (_renegerated_objs != nullptr) {
    delete _renegerated_objs;
  }
}