rename_map.hh revision 2292 
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
29// Todo:  Create destructor.
30// Have it so that there's a more meaningful name given to the variable
31// that marks the beginning of the FP registers.
32
33#ifndef __CPU_O3_RENAME_MAP_HH__
34#define __CPU_O3_RENAME_MAP_HH__
35
36#include <iostream>
37#include <utility>
38#include <vector>
39
40#include "cpu/o3/free_list.hh"
41//For RegIndex
42#include "arch/isa_traits.hh"
43
44class SimpleRenameMap
45{
46  protected:
47    typedef TheISA::RegIndex RegIndex;
48  public:
49    /**
50     * Pair of a logical register and a physical register.  Tells the
51     * previous mapping of a logical register to a physical register.
52     * Used to roll back the rename map to a previous state.
53     */
54    typedef std::pair<RegIndex, PhysRegIndex> UnmapInfo;
55
56    /**
57     * Pair of a physical register and a physical register.  Used to
58     * return the physical register that a logical register has been
59     * renamed to, and the previous physical register that the same
60     * logical register was previously mapped to.
61     */
62    typedef std::pair<PhysRegIndex, PhysRegIndex> RenameInfo;
63
64  public:
65    //Constructor
66     SimpleRenameMap() {};
67
68    /** Destructor. */
69    ~SimpleRenameMap();
70
71    void init(unsigned _numLogicalIntRegs,
72              unsigned _numPhysicalIntRegs,
73              PhysRegIndex &_int_reg_start,
74
75              unsigned _numLogicalFloatRegs,
76              unsigned _numPhysicalFloatRegs,
77              PhysRegIndex &_float_reg_start,
78
79              unsigned _numMiscRegs,
80
81              RegIndex _intZeroReg,
82              RegIndex _floatZeroReg,
83
84              int id,
85              bool bindRegs);
86
87    void setFreeList(SimpleFreeList *fl_ptr);
88
89    //Tell rename map to get a free physical register for a given
90    //architected register.  Not sure it should have a return value,
91    //but perhaps it should have some sort of fault in case there are
92    //no free registers.
93    RenameInfo rename(RegIndex arch_reg);
94
95    PhysRegIndex lookup(RegIndex phys_reg);
96
97    /**
98     * Marks the given register as ready, meaning that its value has been
99     * calculated and written to the register file.
100     * @param ready_reg The index of the physical register that is now ready.
101     */
102    void setEntry(RegIndex arch_reg, PhysRegIndex renamed_reg);
103
104    void squash(std::vector<RegIndex> freed_regs,
105                std::vector<UnmapInfo> unmaps);
106
107    int numFreeEntries();
108
109  private:
110    /** Rename Map ID  */
111    int id;
112
113    /** Number of logical integer registers. */
114    int numLogicalIntRegs;
115
116    /** Number of physical integer registers. */
117    int numPhysicalIntRegs;
118
119    /** Number of logical floating point registers. */
120    int numLogicalFloatRegs;
121
122    /** Number of physical floating point registers. */
123    int numPhysicalFloatRegs;
124
125    /** Number of miscellaneous registers. */
126    int numMiscRegs;
127
128    /** Number of logical integer + float registers. */
129    int numLogicalRegs;
130
131    /** Number of physical integer + float registers. */
132    int numPhysicalRegs;
133
134    /** The integer zero register.  This implementation assumes it is always
135     *  zero and never can be anything else.
136     */
137    RegIndex intZeroReg;
138
139    /** The floating point zero register.  This implementation assumes it is
140     *  always zero and never can be anything else.
141     */
142    RegIndex floatZeroReg;
143
144    class RenameEntry
145    {
146      public:
147        PhysRegIndex physical_reg;
148        bool valid;
149
150        RenameEntry()
151            : physical_reg(0), valid(false)
152        { }
153    };
154
155    //Change this to private
156  public:
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