src/mem/ruby/system/AbstractReplacementPolicy.hh

   1 /*
   2  * Copyright (c) 2007 Mark D. Hill and David A. Wood
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #ifndef __MEM_RUBY_SYSTEM_ABSTRACTREPLACEMENTPOLICY_HH__
  30 #define __MEM_RUBY_SYSTEM_ABSTRACTREPLACEMENTPOLICY_HH__
  31
  32 #include "base/types.hh"
  33
  34 class AbstractReplacementPolicy
  35 {
  36   public:
  37     AbstractReplacementPolicy(Index num_sets, Index assoc);
  38     virtual ~AbstractReplacementPolicy();
  39
  40     /* touch a block. a.k.a. update timestamp */
  41     virtual void touch(Index set, Index way, Tick time) = 0;
  42
  43     /* returns the way to replace */
  44     virtual Index getVictim(Index set) const = 0;
  45
  46     /* get the time of the last access */
  47     Tick getLastAccess(Index set, Index way);
  48
  49   protected:
  50     unsigned m_num_sets;       /** total number of sets */
  51     unsigned m_assoc;          /** set associativity */
  52     Tick **m_last_ref_ptr;         /** timestamp of last reference */
  53 };
  54
  55 inline
  56 AbstractReplacementPolicy::AbstractReplacementPolicy(Index num_sets,
  57                                                      Index assoc)
  58 {
  59     m_num_sets = num_sets;
  60     m_assoc = assoc;
  61     m_last_ref_ptr = new Tick*[m_num_sets];
  62     for(unsigned i = 0; i < m_num_sets; i++){
  63         m_last_ref_ptr[i] = new Tick[m_assoc];
  64         for(unsigned j = 0; j < m_assoc; j++){
  65             m_last_ref_ptr[i][j] = 0;
  66         }
  67     }
  68 }
  69
  70 inline
  71 AbstractReplacementPolicy::~AbstractReplacementPolicy()
  72 {
  73     if (m_last_ref_ptr != NULL){
  74         for (unsigned i = 0; i < m_num_sets; i++){
  75             if (m_last_ref_ptr[i] != NULL){
  76                 delete[] m_last_ref_ptr[i];
  77             }
  78         }
  79         delete[] m_last_ref_ptr;
  80     }
  81 }
  82
  83 inline Tick
  84 AbstractReplacementPolicy::getLastAccess(Index set, Index way)
  85 {
  86     return m_last_ref_ptr[set][way];
  87 }
  88
  89 #endif // __MEM_RUBY_SYSTEM_ABSTRACTREPLACEMENTPOLICY_HH__