class/corlib/System.Reflection.Emit/OpCode.cs

   1 //
   2 // System.Reflection.Emit.OpCode
   3 //
   4 // Author:
   5 //   Duncan Mak (duncan@ximian.com)
   6 //
   7 // Permission is hereby granted, free of charge, to any person obtaining
   8 // a copy of this software and associated documentation files (the
   9 // "Software"), to deal in the Software without restriction, including
  10 // without limitation the rights to use, copy, modify, merge, publish,
  11 // distribute, sublicense, and/or sell copies of the Software, and to
  12 // permit persons to whom the Software is furnished to do so, subject to
  13 // the following conditions:
  14 //
  15 // The above copyright notice and this permission notice shall be
  16 // included in all copies or substantial portions of the Software.
  17 //
  18 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  22 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25 //
  26 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  27 //
  28
  29 using System;
  30 using System.Reflection;
  31 using System.Reflection.Emit;
  32 using System.Runtime.InteropServices;
  33
  34 namespace System.Reflection.Emit {
  35
  36         [ComVisible (true)]
  37         public struct OpCode {
  38
  39                 internal byte op1, op2;
  40                 byte push, pop, size, type, args, flow;
  41
  42                 //
  43                 // The order is:
  44                 //       Op1, Op2, StackBehaviourPush, StackBehaviourPop
  45                 //       Size, OpCodeType, OperandType, FlowControl
  46                 //
  47                 internal OpCode (int p, int q)
  48                 {
  49
  50                         op1  = (byte) ((p >> 0)  & 0xFF);
  51                         op2  = (byte) ((p >> 8)  & 0xFF);
  52                         push = (byte) ((p >> 16) & 0xFF);
  53                         pop  = (byte) ((p >> 24) & 0xFF);
  54
  55                         size = (byte) ((q >> 0)  & 0xFF);
  56                         type = (byte) ((q >> 8)  & 0xFF);
  57                         args = (byte) ((q >> 16) & 0xFF);
  58                         flow = (byte) ((q >> 24) & 0xFF);
  59                 }
  60
  61
  62                 public override int GetHashCode ()
  63                 {
  64                         return Name.GetHashCode ();
  65                 }
  66
  67                 public override bool Equals (Object obj)
  68                 {
  69                         if (obj == null || !(obj is OpCode))
  70                                 return false;
  71
  72                         OpCode v = (OpCode) obj;
  73
  74                         return v.op1 == op1 && v.op2 == op2;
  75                 }
  76
  77                 public bool Equals (OpCode obj)
  78                 {
  79                         return obj.op1 == op1 && obj.op2 == op2;
  80                 }
  81
  82                 public override string ToString ()
  83                 {
  84                         return Name;
  85                 }
  86
  87                 public string Name {
  88                         get {
  89                                 if (op1 == 0xFF)
  90                                         return OpCodeNames.names [op2];
  91
  92                                 return OpCodeNames.names [256 + op2];
  93                         }
  94                 }
  95
  96                 public int Size {
  97                         get {
  98                                 return (int) size;
  99                         }
 100                 }
 101
 102                 public OpCodeType OpCodeType {
 103                         get {
 104                                 return (OpCodeType) type;
 105                         }
 106                 }
 107
 108                 public OperandType OperandType {
 109                         get {
 110                                 return (OperandType) args;
 111                         }
 112                 }
 113
 114                 public FlowControl FlowControl {
 115                         get {
 116                                 return (FlowControl) flow;
 117                         }
 118                 }
 119
 120                 public StackBehaviour StackBehaviourPop {
 121                         get {
 122                                 return (StackBehaviour) pop;
 123                         }
 124                 }
 125
 126                 public StackBehaviour StackBehaviourPush {
 127                         get {
 128                                 return (StackBehaviour) push;
 129                         }
 130                 }
 131
 132                 public short Value {
 133                         get {
 134                                 if (size == 1) {
 135                                         return op2;
 136                                 } else {
 137                                         // two byte instruction - combine
 138                                         // Some old MS betas returned (op1 << 2) | op2 here...
 139                                         return (short) ((op1 << 8) | op2);
 140                                 }
 141                         }
 142                 }
 143
 144                 public static bool operator == (OpCode a, OpCode b)
 145                 {
 146                         return a.op1 == b.op1 && a.op2 == b.op2;
 147                 }
 148
 149                 public static bool operator != (OpCode a, OpCode b)
 150                 {
 151                         return a.op1 != b.op1 || a.op2 != b.op2;
 152                 }
 153         }
 154 }