scoreboard.hh revision 2669:f2b336e89d2a 
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#ifndef __CPU_O3_SCOREBOARD_HH__
30#define __CPU_O3_SCOREBOARD_HH__
31
32#include <iostream>
33#include <utility>
34#include <vector>
35#include "arch/alpha/isa_traits.hh"
36#include "base/trace.hh"
37#include "base/traceflags.hh"
38#include "cpu/o3/comm.hh"
39
40/**
41 * Implements a simple scoreboard to track which registers are ready.
42 * This class assumes that the fp registers start, index wise, right after
43 * the integer registers. The misc. registers start, index wise, right after
44 * the fp registers.
45 * @todo: Fix up handling of the zero register in case the decoder does not
46 * automatically make insts that write the zero register into nops.
47 */
48class Scoreboard
49{
50  public:
51    /** Constructs a scoreboard.
52     *  @param activeThreads The number of active threads.
53     *  @param _numLogicalIntRegs Number of logical integer registers.
54     *  @param _numPhysicalIntRegs Number of physical integer registers.
55     *  @param _numLogicalFloatRegs Number of logical fp registers.
56     *  @param _numPhysicalFloatRegs Number of physical fp registers.
57     *  @param _numMiscRegs Number of miscellaneous registers.
58     *  @param _zeroRegIdx Index of the zero register.
59     */
60    Scoreboard(unsigned activeThreads,
61               unsigned _numLogicalIntRegs,
62               unsigned _numPhysicalIntRegs,
63               unsigned _numLogicalFloatRegs,
64               unsigned _numPhysicalFloatRegs,
65               unsigned _numMiscRegs,
66               unsigned _zeroRegIdx);
67
68    /** Destructor. */
69    ~Scoreboard() {}
70
71    /** Returns the name of the scoreboard. */
72    std::string name() const;
73
74    /** Checks if the register is ready. */
75    bool getReg(PhysRegIndex ready_reg);
76
77    /** Sets the register as ready. */
78    void setReg(PhysRegIndex phys_reg);
79
80    /** Sets the register as not ready. */
81    void unsetReg(PhysRegIndex ready_reg);
82
83  private:
84    /** Scoreboard of physical integer registers, saying whether or not they
85     *  are ready.
86     */
87    std::vector<bool> regScoreBoard;
88
89    /** Number of logical integer registers. */
90    int numLogicalIntRegs;
91
92    /** Number of physical integer registers. */
93    int numPhysicalIntRegs;
94
95    /** Number of logical floating point registers. */
96    int numLogicalFloatRegs;
97
98    /** Number of physical floating point registers. */
99    int numPhysicalFloatRegs;
100
101    /** Number of miscellaneous registers. */
102    int numMiscRegs;
103
104    /** Number of logical integer + float registers. */
105    int numLogicalRegs;
106
107    /** Number of physical integer + float registers. */
108    int numPhysicalRegs;
109
110    /** The logical index of the zero register. */
111    int zeroRegIdx;
112};
113
114#endif
115