1 /*
   2  * Copyright 2003 Sun Microsystems, Inc.  All Rights Reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 package sun.jvm.hotspot.asm.x86;
  26 
  27 import sun.jvm.hotspot.utilities.*;
  28 
  29 public class X86SegmentRegisters {
  30 
  31    public static final int NUM_SEGMENT_REGISTERS = 6;
  32 
  33    public static final X86SegmentRegister ES;
  34    public static final X86SegmentRegister CS;
  35    public static final X86SegmentRegister SS;
  36    public static final X86SegmentRegister DS;
  37    public static final X86SegmentRegister FS;
  38    public static final X86SegmentRegister GS;
  39 
  40    private static X86SegmentRegister segmentRegisters[];
  41 
  42    static {
  43       //Segment registers
  44       ES = new X86SegmentRegister(0, "%es");
  45       CS = new X86SegmentRegister(1, "%cs");
  46       SS = new X86SegmentRegister(2, "%ss");
  47       DS = new X86SegmentRegister(3, "%ds");
  48       FS = new X86SegmentRegister(4, "%fs");
  49       GS = new X86SegmentRegister(5, "%gs");
  50 
  51       segmentRegisters = (new X86SegmentRegister[] {
  52             ES, CS, SS, DS, FS, GS
  53       });
  54    }
  55 
  56    public static int getNumberOfRegisters() {
  57       return NUM_SEGMENT_REGISTERS;
  58    }
  59 
  60    public static X86SegmentRegister getSegmentRegister(int regNum) {
  61       if (Assert.ASSERTS_ENABLED) {
  62          Assert.that(regNum > -1 && regNum < NUM_SEGMENT_REGISTERS, "invalid segment register number!");
  63       }
  64      return segmentRegisters[regNum];
  65    }
  66 }