/*

 * 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/edgeStore.hpp"

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

#include "oops/oop.inline.hpp"

RoutableEdge::RoutableEdge() : Edge() {}

RoutableEdge::RoutableEdge(const Edge* parent, const oop* reference) : Edge(parent, reference),

                                                                       _skip_edge(NULL),

                                                                       _skip_length(0),

                                                                       _processed(false) {}

RoutableEdge::RoutableEdge(const Edge& edge) : Edge(edge),

                                               _skip_edge(NULL),

                                               _skip_length(0),

                                               _processed(false) {}

RoutableEdge::RoutableEdge(const RoutableEdge& edge) : Edge(edge),

                                                      _skip_edge(edge._skip_edge),

                                                      _skip_length(edge._skip_length),

                                                      _processed(edge._processed) {}

void RoutableEdge::operator=(const RoutableEdge& edge) {

  Edge::operator=(edge);

  _skip_edge = edge._skip_edge;

  _skip_length = edge._skip_length;

  _processed = edge._processed;

}

size_t RoutableEdge::logical_distance_to_root() const {

  size_t depth = 0;

  const RoutableEdge* current = logical_parent();

  while (current != NULL) {

    depth++;

    current = current->logical_parent();

  }

  return depth;

}

traceid EdgeStore::_edge_id_counter = 0;

EdgeStore::EdgeStore() : _edges(NULL) {

  _edges = new EdgeHashTable(this);

}

EdgeStore::~EdgeStore() {

  assert(_edges != NULL, "invariant");

  delete _edges;

  _edges = NULL;

}

const Edge* EdgeStore::get_edge(const Edge* edge) const {

  assert(edge != NULL, "invariant");

  EdgeEntry* const entry = _edges->lookup_only(*edge, (uintptr_t)edge->reference());

  return entry != NULL ? entry->literal_addr() : NULL;

}

const Edge* EdgeStore::put(const Edge* edge) {

  assert(edge != NULL, "invariant");

  const RoutableEdge e = *edge;

  assert(NULL == _edges->lookup_only(e, (uintptr_t)e.reference()), "invariant");

  EdgeEntry& entry = _edges->put(e, (uintptr_t)e.reference());

  return entry.literal_addr();

}

traceid EdgeStore::get_id(const Edge* edge) const {

  assert(edge != NULL, "invariant");

  EdgeEntry* const entry = _edges->lookup_only(*edge, (uintptr_t)edge->reference());

  assert(entry != NULL, "invariant");

  return entry->id();

}

traceid EdgeStore::get_root_id(const Edge* edge) const {

  assert(edge != NULL, "invariant");

  const Edge* root = EdgeUtils::root(*edge);

  assert(root != NULL, "invariant");

  return get_id(root);

}

void EdgeStore::add_chain(const Edge* chain, size_t length) {

  assert(chain != NULL, "invariant");

  assert(length > 0, "invariant");

  size_t bottom_index = length - 1;

  const size_t top_index = 0;

  const Edge* stored_parent_edge = NULL;

  // determine level of shared ancestry

  for (; bottom_index > top_index; --bottom_index) {

    const Edge* stored_edge = get_edge(&chain[bottom_index]);

    if (stored_edge != NULL) {

      stored_parent_edge = stored_edge;

      continue;

    }

    break;

  }

  // insertion of new Edges

  for (int i = (int)bottom_index; i >= (int)top_index; --i) {

    Edge edge(stored_parent_edge, chain[i].reference());

    stored_parent_edge = put(&edge);

  }

  const oop sample_object = stored_parent_edge->pointee();

  assert(sample_object != NULL, "invariant");

  assert(NULL == sample_object->mark(), "invariant");

  // Install the "top" edge of the chain into the sample object mark oop.

  // This associates the sample object with its navigable reference chain.

  sample_object->set_mark(markOop(stored_parent_edge));

}

bool EdgeStore::is_empty() const {

  return !_edges->has_entries();

}

size_t EdgeStore::number_of_entries() const {

  return _edges->cardinality();

}

void EdgeStore::assign_id(EdgeEntry* entry) {

  assert(entry != NULL, "invariant");

  assert(entry->id() == 0, "invariant");

  entry->set_id(++_edge_id_counter);

}

bool EdgeStore::equals(const Edge& query, uintptr_t hash, const EdgeEntry* entry) {

  assert(entry != NULL, "invariant");

  assert(entry->hash() == hash, "invariant");

  return true;

}