Cosmos/source/Indy.IL2CPU.IL.X86/Castclass.cs
2008-08-02 07:58:19 +00:00

75 lines
No EOL
3.1 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using CPU = Indy.IL2CPU.Assembler;
using CPUx86 = Indy.IL2CPU.Assembler.X86;
using System.Reflection;
using Indy.IL2CPU.Assembler;
namespace Indy.IL2CPU.IL.X86 {
[OpCode(OpCodeEnum.Castclass, false)]
public class Castclass: Op {
private int mTypeId;
private string mThisLabel;
private string mNextOpLabel;
private Type mCastAsType;
private int mCurrentILOffset;
private MethodInformation mMethodInfo;
public static void ScanOp(ILReader aReader, MethodInformation aMethodInfo, SortedList<string, object> aMethodData) {
Type xType = aReader.OperandValueType;
if (xType == null)
{
throw new Exception("Unable to determine Type!");
}
Engine.RegisterType(xType);
Call.ScanOp(Engine.GetMethodBase(typeof(VTablesImpl),
"IsInstance",
"System.Int32",
"System.Int32"));
Newobj.ScanOp(typeof(InvalidCastException).GetConstructor(new Type[0]));
}
public Castclass(ILReader aReader, MethodInformation aMethodInfo)
: base(aReader, aMethodInfo) {
Type xType = aReader.OperandValueType;
if (xType == null) {
throw new Exception("Unable to determine Type!");
}
mCastAsType = xType;
mTypeId = Engine.RegisterType(mCastAsType);
mThisLabel = GetInstructionLabel(aReader);
mNextOpLabel = GetInstructionLabel(aReader.NextPosition);
mCurrentILOffset = (int)aReader.Position;
mMethodInfo = aMethodInfo;
}
public override void DoAssemble() {
// todo: throw an exception when the class does not support the cast!
string mReturnNullLabel = mThisLabel + "_ReturnNull";
new CPUx86.Move(CPUx86.Registers.EAX, CPUx86.Registers.AtESP);
new CPUx86.Compare(CPUx86.Registers.EAX, "0");
new CPUx86.JumpIfZero(mReturnNullLabel);
new CPUx86.Pushd(CPUx86.Registers.AtEAX);
new CPUx86.Pushd("0x" + mTypeId.ToString("X") );
Assembler.StackContents.Push(new StackContent(4, typeof(object)));
Assembler.StackContents.Push(new StackContent(4, typeof(object)));
MethodBase xMethodIsInstance = Engine.GetMethodBase(typeof(VTablesImpl), "IsInstance", "System.Int32", "System.Int32");
Engine.QueueMethod(xMethodIsInstance);
Op xOp = new Call(xMethodIsInstance, mCurrentILOffset, mMethodInfo.DebugMode, mThisLabel + "_After_IsInstance_Call");
xOp.Assembler = Assembler;
xOp.Assemble();
new CPU.Label(mThisLabel + "_After_IsInstance_Call");
Assembler.StackContents.Pop();
new CPUx86.Pop(CPUx86.Registers.EAX);
new CPUx86.Compare(CPUx86.Registers.EAX, "0");
new CPUx86.JumpIfNotEqual(mNextOpLabel);
new CPU.Label(mReturnNullLabel);
new CPUx86.Add("esp", "4");
Newobj.Assemble(Assembler, typeof(InvalidCastException).GetConstructor(new Type[0]), Engine.RegisterType(typeof(InvalidCastException)), mThisLabel, mMethodInfo, mCurrentILOffset);
Call.EmitExceptionLogic(Assembler, mCurrentILOffset, mMethodInfo, mNextOpLabel, false, null);
}
}
}