src/cpu/o3/scoreboard.hh

   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  */
  48 class 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