source: branches/PersistentDataStructures/HeuristicLab.ExtLibs/HeuristicLab.Cecil/0.9.5/Mono.Cecil-0.9.5/Mono.Cecil/Mono.Cecil.Cil/Instruction.cs

//
// Instruction.cs
//
// Author:
//   Jb Evain (jbevain@gmail.com)
//
// Copyright (c) 2008 - 2011 Jb Evain
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Text;

namespace Mono.Cecil.Cil {

  public sealed class Instruction {

    internal int offset;
    internal OpCode opcode;
    internal object operand;

    internal Instruction previous;
    internal Instruction next;

    SequencePoint sequence_point;

    public int Offset {
      get { return offset; }
      set { offset = value; }
    }

    public OpCode OpCode {
      get { return opcode; }
      set { opcode = value; }
    }

    public object Operand {
      get { return operand; }
      set { operand = value; }
    }

    public Instruction Previous {
      get { return previous; }
      set { previous = value; }
    }

    public Instruction Next {
      get { return next; }
      set { next = value; }
    }

    public SequencePoint SequencePoint {
      get { return sequence_point; }
      set { sequence_point = value; }
    }

    internal Instruction (int offset, OpCode opCode)
    {
      this.offset = offset;
      this.opcode = opCode;
    }

    internal Instruction (OpCode opcode, object operand)
    {
      this.opcode = opcode;
      this.operand = operand;
    }

    public int GetSize ()
    {
      int size = opcode.Size;

      switch (opcode.OperandType) {
      case OperandType.InlineSwitch:
        return size + (1 + ((Instruction []) operand).Length) * 4;
      case OperandType.InlineI8:
      case OperandType.InlineR:
        return size + 8;
      case OperandType.InlineBrTarget:
      case OperandType.InlineField:
      case OperandType.InlineI:
      case OperandType.InlineMethod:
      case OperandType.InlineString:
      case OperandType.InlineTok:
      case OperandType.InlineType:
      case OperandType.ShortInlineR:
      case OperandType.InlineSig:
        return size + 4;
      case OperandType.InlineArg:
      case OperandType.InlineVar:
        return size + 2;
      case OperandType.ShortInlineBrTarget:
      case OperandType.ShortInlineI:
      case OperandType.ShortInlineArg:
      case OperandType.ShortInlineVar:
        return size + 1;
      default:
        return size;
      }
    }

    public override string ToString ()
    {
      var instruction = new StringBuilder ();

      AppendLabel (instruction, this);
      instruction.Append (':');
      instruction.Append (' ');
      instruction.Append (opcode.Name);

      if (operand == null)
        return instruction.ToString ();

      instruction.Append (' ');

      switch (opcode.OperandType) {
      case OperandType.ShortInlineBrTarget:
      case OperandType.InlineBrTarget:
        AppendLabel (instruction, (Instruction) operand);
        break;
      case OperandType.InlineSwitch:
        var labels = (Instruction []) operand;
        for (int i = 0; i < labels.Length; i++) {
          if (i > 0)
            instruction.Append (',');

          AppendLabel (instruction, labels [i]);
        }
        break;
      case OperandType.InlineString:
        instruction.Append ('\"');
        instruction.Append (operand);
        instruction.Append ('\"');
        break;
      default:
        instruction.Append (operand);
        break;
      }

      return instruction.ToString ();
    }

    static void AppendLabel (StringBuilder builder, Instruction instruction)
    {
      builder.Append ("IL_");
      builder.Append (instruction.offset.ToString ("x4"));
    }

    public static Instruction Create (OpCode opcode)
    {
      if (opcode.OperandType != OperandType.InlineNone)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, null);
    }

    public static Instruction Create (OpCode opcode, TypeReference type)
    {
      if (type == null)
        throw new ArgumentNullException ("type");
      if (opcode.OperandType != OperandType.InlineType &&
        opcode.OperandType != OperandType.InlineTok)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, type);
    }

    public static Instruction Create (OpCode opcode, CallSite site)
    {
      if (site == null)
        throw new ArgumentNullException ("site");
      if (opcode.Code != Code.Calli)
        throw new ArgumentException ("code");

      return new Instruction (opcode, site);
    }

    public static Instruction Create (OpCode opcode, MethodReference method)
    {
      if (method == null)
        throw new ArgumentNullException ("method");
      if (opcode.OperandType != OperandType.InlineMethod &&
        opcode.OperandType != OperandType.InlineTok)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, method);
    }

    public static Instruction Create (OpCode opcode, FieldReference field)
    {
      if (field == null)
        throw new ArgumentNullException ("field");
      if (opcode.OperandType != OperandType.InlineField &&
        opcode.OperandType != OperandType.InlineTok)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, field);
    }

    public static Instruction Create (OpCode opcode, string value)
    {
      if (value == null)
        throw new ArgumentNullException ("value");
      if (opcode.OperandType != OperandType.InlineString)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, sbyte value)
    {
      if (opcode.OperandType != OperandType.ShortInlineI &&
        opcode != OpCodes.Ldc_I4_S)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, byte value)
    {
      if (opcode.OperandType != OperandType.ShortInlineI ||
        opcode == OpCodes.Ldc_I4_S)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, int value)
    {
      if (opcode.OperandType != OperandType.InlineI)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, long value)
    {
      if (opcode.OperandType != OperandType.InlineI8)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, float value)
    {
      if (opcode.OperandType != OperandType.ShortInlineR)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, double value)
    {
      if (opcode.OperandType != OperandType.InlineR)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, value);
    }

    public static Instruction Create (OpCode opcode, Instruction target)
    {
      if (target == null)
        throw new ArgumentNullException ("target");
      if (opcode.OperandType != OperandType.InlineBrTarget &&
        opcode.OperandType != OperandType.ShortInlineBrTarget)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, target);
    }

    public static Instruction Create (OpCode opcode, Instruction [] targets)
    {
      if (targets == null)
        throw new ArgumentNullException ("targets");
      if (opcode.OperandType != OperandType.InlineSwitch)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, targets);
    }

    public static Instruction Create (OpCode opcode, VariableDefinition variable)
    {
      if (variable == null)
        throw new ArgumentNullException ("variable");
      if (opcode.OperandType != OperandType.ShortInlineVar &&
        opcode.OperandType != OperandType.InlineVar)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, variable);
    }

    public static Instruction Create (OpCode opcode, ParameterDefinition parameter)
    {
      if (parameter == null)
        throw new ArgumentNullException ("parameter");
      if (opcode.OperandType != OperandType.ShortInlineArg &&
        opcode.OperandType != OperandType.InlineArg)
        throw new ArgumentException ("opcode");

      return new Instruction (opcode, parameter);
    }
  }
}