src/cpu/o3/scoreboard.cc

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