mcs/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 #if NET_2_0
  37         [ComVisible (true)]
  38 #endif
  39         public struct OpCode {
  40
  41                 internal byte op1, op2;
  42                 byte push, pop, size, type, args, flow;
  43
  44                 //
  45                 // The order is:
  46                 //       Op1, Op2, StackBehaviourPush, StackBehaviourPop
  47                 //       Size, OpCodeType, OperandType, FlowControl
  48                 //
  49                 internal OpCode (int p, int q)
  50                 {
  51
  52                         op1  = (byte) ((p >> 0)  & 0xFF);
  53                         op2  = (byte) ((p >> 8)  & 0xFF);
  54                         push = (byte) ((p >> 16) & 0xFF);
  55                         pop  = (byte) ((p >> 24) & 0xFF);
  56
  57                         size = (byte) ((q >> 0)  & 0xFF);
  58                         type = (byte) ((q >> 8)  & 0xFF);
  59                         args = (byte) ((q >> 16) & 0xFF);
  60                         flow = (byte) ((q >> 24) & 0xFF);
  61                 }
  62
  63
  64                 public override int GetHashCode ()
  65                 {
  66                         return Value;
  67                 }
  68
  69                 public override bool Equals (Object obj)
  70                 {
  71                         if (obj == null || !(obj is OpCode))
  72                                 return false;
  73
  74                         OpCode v = (OpCode) obj;
  75
  76                         return v.op1 == op1 && v.op2 == op2;
  77                 }
  78
  79 #if NET_2_0
  80                 public bool Equals (OpCode obj)
  81                 {
  82                         return obj.op1 == op1 && obj.op2 == op2;
  83                 }
  84 #endif
  85
  86                 public override string ToString ()
  87                 {
  88                         return Name;
  89                 }
  90
  91                 public string Name {
  92                         get {
  93                                 if (op1 == 0xFF)
  94                                         return OpCodeNames.names [op2];
  95
  96                                 return OpCodeNames.names [256 + op2];
  97                         }
  98                 }
  99
 100                 public int Size {
 101                         get {
 102                                 return (int) size;
 103                         }
 104                 }
 105
 106                 public OpCodeType OpCodeType {
 107                         get {
 108                                 return (OpCodeType) type;
 109                         }
 110                 }
 111
 112                 public OperandType OperandType {
 113                         get {
 114                                 return (OperandType) args;
 115                         }
 116                 }
 117
 118                 public FlowControl FlowControl {
 119                         get {
 120                                 return (FlowControl) flow;
 121                         }
 122                 }
 123
 124                 public StackBehaviour StackBehaviourPop {
 125                         get {
 126                                 return (StackBehaviour) pop;
 127                         }
 128                 }
 129
 130                 public StackBehaviour StackBehaviourPush {
 131                         get {
 132                                 return (StackBehaviour) push;
 133                         }
 134                 }
 135
 136                 public short Value {
 137                         get {
 138                                 if (size == 1) {
 139                                         return op2;
 140                                 } else {
 141                                         // two byte instruction - combine
 142                                         // Some old MS betas returned (op1 << 2) | op2 here...
 143                                         return (short) ((op1 << 8) | op2);
 144                                 }
 145                         }
 146                 }
 147         }
 148 }