/*
 * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates.
 *
 * 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 "gc/shenandoah/shenandoahConnectionMatrix.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.hpp"
#include "gc/shenandoah/shenandoahHeapRegionSet.hpp"
#include "memory/allocation.inline.hpp"
#include "utilities/copy.hpp"

ShenandoahConnectionMatrix::ShenandoahConnectionMatrix(uint max_regions) :
  _stride(max_regions),
  _matrix(NEW_C_HEAP_ARRAY(bool, max_regions * max_regions, mtGC))
{
  clear_all();
}

ShenandoahConnectionMatrix::~ShenandoahConnectionMatrix() {
  FREE_C_HEAP_ARRAY(bool, _matrix);
}

size_t ShenandoahConnectionMatrix::index_of(uint from_idx, uint to_idx) const {
  return from_idx * _stride + to_idx;
}

bool ShenandoahConnectionMatrix::is_connected(uint from_idx, uint to_idx) const {
  return _matrix[index_of(from_idx, to_idx)];
}

void ShenandoahConnectionMatrix::set_connected(uint from_idx, uint to_idx, bool connected) {
  _matrix[index_of(from_idx, to_idx)] = connected;
}

void ShenandoahConnectionMatrix::clear_region(uint idx) {
  for (uint i = 0; i < _stride; i++) {
    set_connected(i, idx, false);
    set_connected(idx, i, false);
  }
}

void ShenandoahConnectionMatrix::clear_all() {
  size_t count = sizeof(bool) * _stride * _stride;
  Copy::fill_to_bytes(_matrix, count, 0);
}

void ShenandoahConnectionMatrix::print_on(outputStream* st) const {
  ShenandoahHeap* heap = ShenandoahHeap::heap();
  uint num_regions = heap->num_regions();
  for (uint from_idx = 0; from_idx < num_regions; from_idx++) {
    ShenandoahHeapRegion* r = heap->regions()->get(from_idx);
    if (! r->is_empty()) {
      uint count = 0;
      for (uint to_idx = 0; to_idx < _stride; to_idx++) {
        if (is_connected(to_idx, from_idx)) {
          count++;
        }
      }

      st->print("Region %u (live: "SIZE_FORMAT", used: "SIZE_FORMAT", garbage: "SIZE_FORMAT") is referenced by %u regions: {", from_idx, r->get_live_data_bytes(), r->used(), r->garbage(), count);
      for (uint to_idx = 0; to_idx < _stride; to_idx++) {
        if (is_connected(to_idx, from_idx)) {
          st->print("%u, ", to_idx);
        }
      }
      st->print_cr("}");
    }
  }
}