cpu/o3/scoreboard.cc

   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 #include "cpu/o3/scoreboard.hh"
  30
  31 Scoreboard::Scoreboard(unsigned activeThreads,
  32                        unsigned _numLogicalIntRegs,
  33                        unsigned _numPhysicalIntRegs,
  34                        unsigned _numLogicalFloatRegs,
  35                        unsigned _numPhysicalFloatRegs,
  36                        unsigned _numMiscRegs,
  37                        unsigned _zeroRegIdx)
  38     : numLogicalIntRegs(_numLogicalIntRegs),
  39       numPhysicalIntRegs(_numPhysicalIntRegs),
  40       numLogicalFloatRegs(_numLogicalFloatRegs),
  41       numPhysicalFloatRegs(_numPhysicalFloatRegs),
  42       numMiscRegs(_numMiscRegs),
  43       zeroRegIdx(_zeroRegIdx)
  44 {
  45     //Get Register Sizes
  46     numLogicalRegs = numLogicalIntRegs  + numLogicalFloatRegs;
  47     numPhysicalRegs = numPhysicalIntRegs  + numPhysicalFloatRegs;
  48
  49     //Resize scoreboard appropriately
  50     regScoreBoard.resize(numPhysicalRegs + (numMiscRegs * activeThreads));
  51
  52     //Initialize values
  53     for (int i=0; i < numLogicalIntRegs * activeThreads; i++) {
  54         regScoreBoard[i] = 1;
  55     }
  56
  57     for (int i= numPhysicalIntRegs;
  58          i < numPhysicalIntRegs + (numLogicalFloatRegs * activeThreads);
  59          i++) {
  60         regScoreBoard[i] = 1;
  61     }
  62
  63     for (int i = numPhysicalRegs;
  64          i < numPhysicalRegs + (numMiscRegs * activeThreads);
  65          i++) {
  66         regScoreBoard[i] = 1;
  67     }
  68 }
  69
  70 std::string
  71 Scoreboard::name() const
  72 {
  73     return "cpu.scoreboard";
  74 }
  75
  76 bool
  77 Scoreboard::getReg(PhysRegIndex phys_reg)
  78 {
  79     // Always ready if int or fp zero reg.
  80     if (phys_reg == zeroRegIdx ||
  81         phys_reg == (zeroRegIdx + numPhysicalIntRegs)) {
  82         return 1;
  83     }
  84
  85     return regScoreBoard[phys_reg];
  86 }
  87
  88 void
  89 Scoreboard::setReg(PhysRegIndex phys_reg)
  90 {
  91     DPRINTF(Scoreboard, "Setting reg %i as ready\n", phys_reg);
  92
  93     regScoreBoard[phys_reg] = 1;
  94 }
  95
  96 void
  97 Scoreboard::unsetReg(PhysRegIndex ready_reg)
  98 {
  99     if (ready_reg == zeroRegIdx ||
 100         ready_reg == (zeroRegIdx + numPhysicalIntRegs)) {
 101         // Don't do anything if int or fp zero reg.
 102         return;
 103     }
 104
 105     regScoreBoard[ready_reg] = 0;
 106 }