AbstractReplacementPolicy.hh revision 10314 
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
34class AbstractReplacementPolicy
35{
36  public:
37    AbstractReplacementPolicy(int64 num_sets, int64 assoc);
38    virtual ~AbstractReplacementPolicy();
39
40    /* touch a block. a.k.a. update timestamp */
41    virtual void touch(int64 set, int64 way, Tick time) = 0;
42
43    /* returns the way to replace */
44    virtual int64 getVictim(int64 set) const = 0;
45
46    /* get the time of the last access */
47    Tick getLastAccess(int64 set, int64 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
55inline
56AbstractReplacementPolicy::AbstractReplacementPolicy(int64 num_sets,
57                                                     int64 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
70inline
71AbstractReplacementPolicy::~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
83inline Tick
84AbstractReplacementPolicy::getLastAccess(int64 set, int64 way)
85{
86    return m_last_ref_ptr[set][way];
87}
88
89#endif // __MEM_RUBY_SYSTEM_ABSTRACTREPLACEMENTPOLICY_HH__
90