/*

 * Copyright (c) 2001, 2015, 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

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 */

#ifndef SHARE_VM_GC_G1_SURVRATEGROUP_HPP

#define SHARE_VM_GC_G1_SURVRATEGROUP_HPP

#include "utilities/numberSeq.hpp"

class G1Predictions;

class SurvRateGroup : public CHeapObj<mtGC> {

private:

  size_t  _stats_arrays_length;

  double* _accum_surv_rate_pred;

  double  _last_pred;

  TruncatedSeq** _surv_rate_pred;

  int _all_regions_allocated;

  size_t _region_num;

  size_t _setup_seq_num;

  void fill_in_last_surv_rates();

  void finalize_predictions(const G1Predictions& predictor);

public:

  SurvRateGroup();

  void reset();

  void start_adding_regions();

  void stop_adding_regions();

  void record_surviving_words(int age_in_group, size_t surv_words);

  void all_surviving_words_recorded(const G1Predictions& predictor, bool update_predictors);

  size_t region_num() const { return _region_num; }

  double accum_surv_rate_pred(int age) const {

    assert(age >= 0, "must be");

    if ((size_t)age < _stats_arrays_length)

      return _accum_surv_rate_pred[age];

    else {

      double diff = (double) (age - _stats_arrays_length + 1);

      return _accum_surv_rate_pred[_stats_arrays_length-1] + diff * _last_pred;

    }

  }

  TruncatedSeq* get_seq(size_t age) const {

    if (age >= _setup_seq_num) {

      guarantee( _setup_seq_num > 0, "invariant" );

      age = _setup_seq_num-1;

    }

    TruncatedSeq* seq = _surv_rate_pred[age];

    guarantee( seq != NULL, "invariant" );

    return seq;

  }

  int next_age_index() {

    ++_region_num;

    return (int) ++_all_regions_allocated;

  }

  int age_in_group(int age_index) const {

    int ret = (int) (_all_regions_allocated - age_index);

    assert( ret >= 0, "invariant" );

    return ret;

  }

  void finished_recalculating_age_indexes() {

    _all_regions_allocated = 0;

  }

};

#endif // SHARE_VM_GC_G1_SURVRATEGROUP_HPP