org/jpc/emulator/memory/codeblock/optimised/OptimisedCompiler.java

   1 /*
   2     JPC-RR: A x86 PC Hardware Emulator
   3     Release 1
   4
   5     Copyright (C) 2007-2009 Isis Innovation Limited
   6     Copyright (C) 2009 H. Ilari Liusvaara
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License version 2 as published by
  10     the Free Software Foundation.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License along
  18     with this program; if not, write to the Free Software Foundation, Inc.,
  19     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20
  21     Based on JPC x86 PC Hardware emulator,
  22     A project from the Physics Dept, The University of Oxford
  23
  24     Details about original JPC can be found at:
  25
  26     www-jpc.physics.ox.ac.uk
  27
  28 */
  29
  30 package org.jpc.emulator.memory.codeblock.optimised;
  31
  32 import org.jpc.emulator.memory.codeblock.*;
  33
  34 /**
  35  *
  36  * @author Chris Dennis
  37  */
  38 public class OptimisedCompiler implements CodeBlockCompiler {
  39
  40     private int bufferOffset;
  41     private int[] bufferMicrocodes;
  42     private int[] bufferPositions;
  43
  44     public OptimisedCompiler()
  45     {
  46         bufferMicrocodes = new int[100];
  47         bufferPositions = new int[100];
  48         bufferOffset = 0;
  49     }
  50
  51
  52     public RealModeCodeBlock getRealModeCodeBlock(InstructionSource source)
  53     {
  54         buildCodeBlockBuffers(source);
  55
  56         int[] newMicrocodes = new int[bufferOffset];
  57         int[] newPositions = new int[bufferOffset];
  58         System.arraycopy(bufferMicrocodes, 0, newMicrocodes, 0, bufferOffset);
  59         System.arraycopy(bufferPositions, 0, newPositions, 0, bufferOffset);
  60
  61         return new RealModeUBlock(newMicrocodes, newPositions);
  62     }
  63
  64     public ProtectedModeCodeBlock getProtectedModeCodeBlock(InstructionSource source)
  65     {
  66         buildCodeBlockBuffers(source);
  67
  68         int[] newMicrocodes = new int[bufferOffset];
  69         int[] newPositions = new int[bufferOffset];
  70         System.arraycopy(bufferMicrocodes, 0, newMicrocodes, 0, bufferOffset);
  71         System.arraycopy(bufferPositions, 0, newPositions, 0, bufferOffset);
  72
  73         return new ProtectedModeUBlock(newMicrocodes, newPositions);
  74     }
  75
  76     public Virtual8086ModeCodeBlock getVirtual8086ModeCodeBlock(InstructionSource source)
  77     {
  78         buildCodeBlockBuffers(source);
  79
  80         int[] newMicrocodes = new int[bufferOffset];
  81         int[] newPositions = new int[bufferOffset];
  82         System.arraycopy(bufferMicrocodes, 0, newMicrocodes, 0, bufferOffset);
  83         System.arraycopy(bufferPositions, 0, newPositions, 0, bufferOffset);
  84
  85         return new Virtual8086ModeUBlock(newMicrocodes, newPositions);
  86     }
  87
  88     private void buildCodeBlockBuffers(InstructionSource source)
  89     {
  90         bufferOffset = 0;
  91         int position = 0;
  92
  93         while(source.getNext()) {
  94             int uCodeLength = source.getLength();
  95             int uCodeX86Length = source.getX86Length();
  96             position += uCodeX86Length;
  97
  98             for(int i = 0; i < uCodeLength; i++) {
  99                 int data = source.getMicrocode();
 100                 try {
 101                     bufferMicrocodes[bufferOffset] = data;
 102                     bufferPositions[bufferOffset] = position;
 103                 } catch (ArrayIndexOutOfBoundsException e) {
 104                     int[] newMicrocodes = new int[bufferMicrocodes.length * 2];
 105                     int[] newPositions = new int[bufferMicrocodes.length * 2];
 106                     System.arraycopy(bufferMicrocodes, 0, newMicrocodes, 0, bufferMicrocodes.length);
 107                     System.arraycopy(bufferPositions, 0, newPositions, 0, bufferPositions.length);
 108                     bufferMicrocodes = newMicrocodes;
 109                     bufferPositions = newPositions;
 110                     bufferMicrocodes[bufferOffset] = data;
 111                     bufferPositions[bufferOffset] = position;
 112                 }
 113                 bufferOffset++;
 114             }
 115         }
 116     }
 117 }