/*

 * Copyright (c) 2014, 2018, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "jfr/leakprofiler/chains/bitset.hpp"

#include "jfr/recorder/storage/jfrVirtualMemory.hpp"

#include "memory/memRegion.hpp"

BitSet::BitSet(const MemRegion& covered_region) :

  _vmm(NULL),

  _region_start(covered_region.start()),

  _region_size(covered_region.word_size()) {

}

BitSet::~BitSet() {

  delete _vmm;

}

bool BitSet::initialize() {

  assert(_vmm == NULL, "invariant");

  _vmm = new JfrVirtualMemory();

  if (_vmm == NULL) {

    return false;

  }

  const BitMap::idx_t bits = _region_size >> LogMinObjAlignment;

  const size_t words = bits / BitsPerWord;

  const size_t raw_bytes = words * sizeof(BitMap::idx_t);

  // the virtual memory invocation will reserve and commit the entire space

  BitMap::bm_word_t* map = (BitMap::bm_word_t*)_vmm->initialize(raw_bytes, raw_bytes);

  if (map == NULL) {

    return false;

  }

  _bits = BitMapView(map, bits);

  return true;

}