1 /*
   2  * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
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   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_GC_G1_G1SURVRATEGROUP_HPP
  26 #define SHARE_GC_G1_G1SURVRATEGROUP_HPP
  27 
  28 #include "gc/g1/g1Predictions.hpp"
  29 #include "utilities/numberSeq.hpp"
  30 
  31 class SurvRateGroup : public CHeapObj<mtGC> {
  32   size_t  _stats_arrays_length;
  33   double* _accum_surv_rate_pred;
  34   double  _last_pred;
  35   TruncatedSeq** _surv_rate_predictors;
  36 
  37   size_t _num_added_regions;   // The number of regions in this SurvRateGroup
  38 
  39   void fill_in_last_surv_rates();
  40   void finalize_predictions(const G1Predictions& predictor);
  41 
  42 public:
  43   static const int InvalidAgeIndex = -1;
  44   static bool is_valid_age_index(int age) { return age >= 0; }
  45 
  46   SurvRateGroup();
  47   void reset();
  48   void start_adding_regions();
  49   void stop_adding_regions();
  50   void record_surviving_words(int age_in_group, size_t surv_words);
  51   void all_surviving_words_recorded(const G1Predictions& predictor, bool update_predictors);
  52 
  53   double accum_surv_rate_pred(int age) const {
  54     assert(_stats_arrays_length > 0, "invariant" );
  55     assert(is_valid_age_index(age), "must be");
  56     if ((size_t)age < _stats_arrays_length)
  57       return _accum_surv_rate_pred[age];
  58     else {
  59       double diff = (double)(age - _stats_arrays_length + 1);
  60       return _accum_surv_rate_pred[_stats_arrays_length - 1] + diff * _last_pred;
  61     }
  62   }
  63 
  64   double surv_rate_pred(G1Predictions const& predictor, int age) const {
  65     assert(is_valid_age_index(age), "must be");
  66 
  67     age = MIN2(age, (int)_stats_arrays_length - 1);
  68 
  69     return predictor.predict_in_unit_interval(_surv_rate_predictors[age]);
  70   }
  71 
  72   int next_age_index() {
  73     return (int)++_num_added_regions;
  74   }
  75 
  76   int age_in_group(int age_index) const {
  77     int result = (int)(_num_added_regions - age_index);
  78     assert(is_valid_age_index(result), "invariant" );
  79     return result;
  80   }
  81 };
  82 
  83 #endif // SHARE_GC_G1_G1SURVRATEGROUP_HPP