rename_map.hh revision 2674:6d4afef73a20 
1/*
2 * Copyright (c) 2004-2005 The Regents of The University of Michigan
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 * Authors: Kevin Lim
29 */
30
31// Todo:  Create destructor.
32// Have it so that there's a more meaningful name given to the variable
33// that marks the beginning of the FP registers.
34
35#ifndef __CPU_O3_RENAME_MAP_HH__
36#define __CPU_O3_RENAME_MAP_HH__
37
38#include <iostream>
39#include <utility>
40#include <vector>
41
42#include "cpu/o3/free_list.hh"
43//For RegIndex
44#include "arch/isa_traits.hh"
45
46class SimpleRenameMap
47{
48  protected:
49    typedef TheISA::RegIndex RegIndex;
50  public:
51    /**
52     * Pair of a logical register and a physical register.  Tells the
53     * previous mapping of a logical register to a physical register.
54     * Used to roll back the rename map to a previous state.
55     */
56    typedef std::pair<RegIndex, PhysRegIndex> UnmapInfo;
57
58    /**
59     * Pair of a physical register and a physical register.  Used to
60     * return the physical register that a logical register has been
61     * renamed to, and the previous physical register that the same
62     * logical register was previously mapped to.
63     */
64    typedef std::pair<PhysRegIndex, PhysRegIndex> RenameInfo;
65
66  public:
67    /** Default constructor.  init() must be called prior to use. */
68    SimpleRenameMap() {};
69
70    /** Destructor. */
71    ~SimpleRenameMap();
72
73    /** Initializes rename map with given parameters. */
74    void init(unsigned _numLogicalIntRegs,
75              unsigned _numPhysicalIntRegs,
76              PhysRegIndex &_int_reg_start,
77
78              unsigned _numLogicalFloatRegs,
79              unsigned _numPhysicalFloatRegs,
80              PhysRegIndex &_float_reg_start,
81
82              unsigned _numMiscRegs,
83
84              RegIndex _intZeroReg,
85              RegIndex _floatZeroReg,
86
87              int id,
88              bool bindRegs);
89
90    /** Sets the free list used with this rename map. */
91    void setFreeList(SimpleFreeList *fl_ptr);
92
93    //Tell rename map to get a free physical register for a given
94    //architected register.  Not sure it should have a return value,
95    //but perhaps it should have some sort of fault in case there are
96    //no free registers.
97    RenameInfo rename(RegIndex arch_reg);
98
99    PhysRegIndex lookup(RegIndex phys_reg);
100
101    /**
102     * Marks the given register as ready, meaning that its value has been
103     * calculated and written to the register file.
104     * @param ready_reg The index of the physical register that is now ready.
105     */
106    void setEntry(RegIndex arch_reg, PhysRegIndex renamed_reg);
107
108    int numFreeEntries();
109
110  private:
111    /** Rename Map ID  */
112    int id;
113
114    /** Number of logical integer registers. */
115    int numLogicalIntRegs;
116
117    /** Number of physical integer registers. */
118    int numPhysicalIntRegs;
119
120    /** Number of logical floating point registers. */
121    int numLogicalFloatRegs;
122
123    /** Number of physical floating point registers. */
124    int numPhysicalFloatRegs;
125
126    /** Number of miscellaneous registers. */
127    int numMiscRegs;
128
129    /** Number of logical integer + float registers. */
130    int numLogicalRegs;
131
132    /** Number of physical integer + float registers. */
133    int numPhysicalRegs;
134
135    /** The integer zero register.  This implementation assumes it is always
136     *  zero and never can be anything else.
137     */
138    RegIndex intZeroReg;
139
140    /** The floating point zero register.  This implementation assumes it is
141     *  always zero and never can be anything else.
142     */
143    RegIndex floatZeroReg;
144
145    class RenameEntry
146    {
147      public:
148        PhysRegIndex physical_reg;
149        bool valid;
150
151        RenameEntry()
152            : physical_reg(0), valid(false)
153        { }
154    };
155
156  private:
157    /** Integer rename map. */
158    std::vector<RenameEntry> intRenameMap;
159
160    /** Floating point rename map. */
161    std::vector<RenameEntry> floatRenameMap;
162
163  private:
164    /** Free list interface. */
165    SimpleFreeList *freeList;
166};
167
168#endif //__CPU_O3_RENAME_MAP_HH__
169