scoreboard.cc revision 8232 
1/*
2 * Copyright (c) 2005-2006 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: Korey Sewell
29 *          Kevin Lim
30 */
31
32#include "config/the_isa.hh"
33#include "cpu/o3/scoreboard.hh"
34#include "debug/Scoreboard.hh"
35
36Scoreboard::Scoreboard(unsigned activeThreads,
37                       unsigned _numLogicalIntRegs,
38                       unsigned _numPhysicalIntRegs,
39                       unsigned _numLogicalFloatRegs,
40                       unsigned _numPhysicalFloatRegs,
41                       unsigned _numMiscRegs,
42                       unsigned _zeroRegIdx)
43    : numLogicalIntRegs(_numLogicalIntRegs),
44      numPhysicalIntRegs(_numPhysicalIntRegs),
45      numLogicalFloatRegs(_numLogicalFloatRegs),
46      numPhysicalFloatRegs(_numPhysicalFloatRegs),
47      numMiscRegs(_numMiscRegs),
48      zeroRegIdx(_zeroRegIdx)
49{
50    //Get Register Sizes
51    numLogicalRegs = numLogicalIntRegs  + numLogicalFloatRegs;
52    numPhysicalRegs = numPhysicalIntRegs  + numPhysicalFloatRegs;
53
54    //Resize scoreboard appropriately
55    resize(numPhysicalRegs + (numMiscRegs * activeThreads));
56
57    //Initialize values
58    for (int i=0; i < numLogicalIntRegs * activeThreads; i++) {
59        assert(indexInBounds(i));
60        regScoreBoard[i] = 1;
61    }
62
63    for (int i= numPhysicalIntRegs;
64         i < numPhysicalIntRegs + (numLogicalFloatRegs * activeThreads);
65         i++) {
66        assert(indexInBounds(i));
67        regScoreBoard[i] = 1;
68    }
69
70    for (int i = numPhysicalRegs;
71         i < numPhysicalRegs + (numMiscRegs * activeThreads);
72         i++) {
73        assert(indexInBounds(i));
74        regScoreBoard[i] = 1;
75    }
76}
77
78std::string
79Scoreboard::name() const
80{
81    return "cpu.scoreboard";
82}
83
84bool
85Scoreboard::getReg(PhysRegIndex phys_reg)
86{
87#if THE_ISA == ALPHA_ISA
88    // Always ready if int or fp zero reg.
89    if (phys_reg == zeroRegIdx ||
90        phys_reg == (zeroRegIdx + numPhysicalIntRegs)) {
91        return 1;
92    }
93#else
94    // Always ready if int zero reg.
95    if (phys_reg == zeroRegIdx) {
96        return 1;
97    }
98#endif
99
100    assert(indexInBounds(phys_reg));
101    return regScoreBoard[phys_reg];
102}
103
104void
105Scoreboard::setReg(PhysRegIndex phys_reg)
106{
107    DPRINTF(Scoreboard, "Setting reg %i as ready\n", phys_reg);
108
109    assert(indexInBounds(phys_reg));
110    regScoreBoard[phys_reg] = 1;
111}
112
113void
114Scoreboard::unsetReg(PhysRegIndex ready_reg)
115{
116#if THE_ISA == ALPHA_ISA
117    if (ready_reg == zeroRegIdx ||
118        ready_reg == (zeroRegIdx + numPhysicalIntRegs)) {
119        // Don't do anything if int or fp zero reg.
120        return;
121    }
122#else
123    if (ready_reg == zeroRegIdx) {
124        // Don't do anything if int zero reg.
125        return;
126    }
127#endif
128
129    assert(indexInBounds(ready_reg));
130    regScoreBoard[ready_reg] = 0;
131}
132