Exemplo n.º 1
0
 internal void LoadFirstArgAddress(TypeWrapper tw)
 {
     ilgen.EmitLdarg(0);
     if (tw.IsGhost)
     {
         tw.EmitConvStackTypeToSignatureType(ilgen, null);
         CodeEmitterLocal local = ilgen.DeclareLocal(tw.TypeAsSignatureType);
         ilgen.Emit(OpCodes.Stloc, local);
         ilgen.Emit(OpCodes.Ldloca, local);
     }
     else if (tw.IsNonPrimitiveValueType)
     {
         ilgen.Emit(OpCodes.Unbox, tw.TypeAsSignatureType);
     }
     else
     {
         throw new InvalidOperationException();
     }
 }
Exemplo n.º 2
0
        internal override void Generate(CodeGenContext context, CodeEmitter ilgen)
        {
            CodeEmitterLocal lb = (CodeEmitterLocal)context[Name];

            if (lb == null)
            {
                if (typeWrapper == null && typeType == null)
                {
                    Debug.Assert(Class == null ^ type == null);
                    if (type != null)
                    {
                        typeType = StaticCompiler.GetTypeForMapXml(context.ClassLoader, type);
                    }
                    else
                    {
                        typeWrapper = context.ClassLoader.LoadClassByDottedName(Class);
                    }
                }
                lb            = ilgen.DeclareLocal(typeType != null ? typeType : typeWrapper.TypeAsTBD);
                context[Name] = lb;
            }
            ilgen.Emit(OpCodes.Stloc, lb);
        }
Exemplo n.º 3
0
 internal sealed override void Generate(CodeGenContext context, CodeEmitter ilgen)
 {
     Debug.Assert(Name != null);
     if (Name == ".ctor")
     {
         Debug.Assert(Class == null && type != null);
         Type[]          argTypes = context.ClassLoader.ArgTypeListFromSig(Sig);
         ConstructorInfo ci       = StaticCompiler.GetTypeForMapXml(context.ClassLoader, type).GetConstructor(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance, null, CallingConventions.Standard, argTypes, null);
         if (ci == null)
         {
             throw new InvalidOperationException("Missing .ctor: " + type + "..ctor" + Sig);
         }
         ilgen.Emit(opcode, ci);
     }
     else
     {
         Debug.Assert(Class == null ^ type == null);
         if (Class != null)
         {
             Debug.Assert(Sig != null);
             MethodWrapper method = context.ClassLoader.LoadClassByDottedName(Class).GetMethodWrapper(Name, Sig, false);
             if (method == null)
             {
                 throw new InvalidOperationException("method not found: " + Class + "." + Name + Sig);
             }
             method.Link();
             // TODO this code is part of what Compiler.CastInterfaceArgs (in compiler.cs) does,
             // it would be nice if we could avoid this duplication...
             TypeWrapper[] argTypeWrappers = method.GetParameters();
             for (int i = 0; i < argTypeWrappers.Length; i++)
             {
                 if (argTypeWrappers[i].IsGhost)
                 {
                     CodeEmitterLocal[] temps = new CodeEmitterLocal[argTypeWrappers.Length + (method.IsStatic ? 0 : 1)];
                     for (int j = temps.Length - 1; j >= 0; j--)
                     {
                         TypeWrapper tw;
                         if (method.IsStatic)
                         {
                             tw = argTypeWrappers[j];
                         }
                         else
                         {
                             if (j == 0)
                             {
                                 tw = method.DeclaringType;
                             }
                             else
                             {
                                 tw = argTypeWrappers[j - 1];
                             }
                         }
                         if (tw.IsGhost)
                         {
                             tw.EmitConvStackTypeToSignatureType(ilgen, null);
                         }
                         temps[j] = ilgen.DeclareLocal(tw.TypeAsSignatureType);
                         ilgen.Emit(OpCodes.Stloc, temps[j]);
                     }
                     for (int j = 0; j < temps.Length; j++)
                     {
                         ilgen.Emit(OpCodes.Ldloc, temps[j]);
                     }
                     break;
                 }
             }
             if (opcode.Value == OpCodes.Call.Value)
             {
                 method.EmitCall(ilgen);
             }
             else if (opcode.Value == OpCodes.Callvirt.Value)
             {
                 method.EmitCallvirt(ilgen);
             }
             else if (opcode.Value == OpCodes.Newobj.Value)
             {
                 method.EmitNewobj(ilgen);
             }
             else
             {
                 // ldftn or ldvirtftn
                 ilgen.Emit(opcode, (MethodInfo)method.GetMethod());
             }
         }
         else
         {
             Type[] argTypes;
             if (Sig.StartsWith("("))
             {
                 argTypes = context.ClassLoader.ArgTypeListFromSig(Sig);
             }
             else if (Sig == "")
             {
                 argTypes = Type.EmptyTypes;
             }
             else
             {
                 string[] types = Sig.Split(';');
                 argTypes = new Type[types.Length];
                 for (int i = 0; i < types.Length; i++)
                 {
                     argTypes[i] = StaticCompiler.GetTypeForMapXml(context.ClassLoader, types[i]);
                 }
             }
             MethodInfo mi = StaticCompiler.GetTypeForMapXml(context.ClassLoader, type).GetMethod(Name, BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static, null, argTypes, null);
             if (mi == null)
             {
                 throw new InvalidOperationException("Missing method: " + type + "." + Name + Sig);
             }
             ilgen.Emit(opcode, mi);
         }
     }
 }
Exemplo n.º 4
0
        internal FastFieldReflector(java.io.ObjectStreamField[] fields)
        {
            this.fields = fields;
            TypeWrapper tw = null;

            foreach (java.io.ObjectStreamField field in fields)
            {
                FieldWrapper fw = GetFieldWrapper(field);
                if (fw != null)
                {
                    if (tw == null)
                    {
                        tw = fw.DeclaringType;
                    }
                    else if (tw != fw.DeclaringType)
                    {
                        // pre-condition is that all fields are from the same Type!
                        throw new java.lang.InternalError();
                    }
                }
            }
            if (tw == null)
            {
                objFieldGetter  = objFieldSetter = objDummy;
                primFieldGetter = primFieldSetter = primDummy;
            }
            else
            {
                try
                {
                    tw.Finish();
                }
                catch (RetargetableJavaException x)
                {
                    throw x.ToJava();
                }
                DynamicMethod dmObjGetter     = DynamicMethodUtils.Create("__<ObjFieldGetter>", tw.TypeAsBaseType, true, null, new Type[] { typeof(object), typeof(object[]) });
                DynamicMethod dmPrimGetter    = DynamicMethodUtils.Create("__<PrimFieldGetter>", tw.TypeAsBaseType, true, null, new Type[] { typeof(object), typeof(byte[]) });
                DynamicMethod dmObjSetter     = DynamicMethodUtils.Create("__<ObjFieldSetter>", tw.TypeAsBaseType, true, null, new Type[] { typeof(object), typeof(object[]) });
                DynamicMethod dmPrimSetter    = DynamicMethodUtils.Create("__<PrimFieldSetter>", tw.TypeAsBaseType, true, null, new Type[] { typeof(object), typeof(byte[]) });
                CodeEmitter   ilgenObjGetter  = CodeEmitter.Create(dmObjGetter);
                CodeEmitter   ilgenPrimGetter = CodeEmitter.Create(dmPrimGetter);
                CodeEmitter   ilgenObjSetter  = CodeEmitter.Create(dmObjSetter);
                CodeEmitter   ilgenPrimSetter = CodeEmitter.Create(dmPrimSetter);

                // we want the getters to be verifiable (because writeObject can be used from partial trust),
                // so we create a local to hold the properly typed object reference
                CodeEmitterLocal objGetterThis  = ilgenObjGetter.DeclareLocal(tw.TypeAsBaseType);
                CodeEmitterLocal primGetterThis = ilgenPrimGetter.DeclareLocal(tw.TypeAsBaseType);
                ilgenObjGetter.Emit(OpCodes.Ldarg_0);
                ilgenObjGetter.Emit(OpCodes.Castclass, tw.TypeAsBaseType);
                ilgenObjGetter.Emit(OpCodes.Stloc, objGetterThis);
                ilgenPrimGetter.Emit(OpCodes.Ldarg_0);
                ilgenPrimGetter.Emit(OpCodes.Castclass, tw.TypeAsBaseType);
                ilgenPrimGetter.Emit(OpCodes.Stloc, primGetterThis);

                foreach (java.io.ObjectStreamField field in fields)
                {
                    FieldWrapper fw = GetFieldWrapper(field);
                    if (fw == null)
                    {
                        continue;
                    }
                    fw.ResolveField();
                    TypeWrapper fieldType = fw.FieldTypeWrapper;
                    try
                    {
                        fieldType = fieldType.EnsureLoadable(tw.GetClassLoader());
                        fieldType.Finish();
                    }
                    catch (RetargetableJavaException x)
                    {
                        throw x.ToJava();
                    }
                    if (fieldType.IsPrimitive)
                    {
                        // Getter
                        ilgenPrimGetter.Emit(OpCodes.Ldarg_1);
                        ilgenPrimGetter.EmitLdc_I4(field.getOffset());
                        ilgenPrimGetter.Emit(OpCodes.Ldloc, primGetterThis);
                        fw.EmitGet(ilgenPrimGetter);
                        if (fieldType == PrimitiveTypeWrapper.BYTE)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteByteMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.BOOLEAN)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteBooleanMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.CHAR)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteCharMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.SHORT)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteShortMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.INT)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteIntMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.FLOAT)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteFloatMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.LONG)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteLongMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.DOUBLE)
                        {
                            ilgenPrimGetter.Emit(OpCodes.Call, WriteDoubleMethod);
                        }
                        else
                        {
                            throw new java.lang.InternalError();
                        }

                        // Setter
                        ilgenPrimSetter.Emit(OpCodes.Ldarg_0);
                        ilgenPrimSetter.Emit(OpCodes.Castclass, tw.TypeAsBaseType);
                        ilgenPrimSetter.Emit(OpCodes.Ldarg_1);
                        ilgenPrimSetter.EmitLdc_I4(field.getOffset());
                        if (fieldType == PrimitiveTypeWrapper.BYTE)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadByteMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.BOOLEAN)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadBooleanMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.CHAR)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadCharMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.SHORT)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadShortMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.INT)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadIntMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.FLOAT)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadFloatMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.LONG)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadLongMethod);
                        }
                        else if (fieldType == PrimitiveTypeWrapper.DOUBLE)
                        {
                            ilgenPrimSetter.Emit(OpCodes.Call, ReadDoubleMethod);
                        }
                        else
                        {
                            throw new java.lang.InternalError();
                        }
                        fw.EmitSet(ilgenPrimSetter);
                    }
                    else
                    {
                        // Getter
                        ilgenObjGetter.Emit(OpCodes.Ldarg_1);
                        ilgenObjGetter.EmitLdc_I4(field.getOffset());
                        ilgenObjGetter.Emit(OpCodes.Ldloc, objGetterThis);
                        fw.EmitGet(ilgenObjGetter);
                        fieldType.EmitConvSignatureTypeToStackType(ilgenObjGetter);
                        ilgenObjGetter.Emit(OpCodes.Stelem_Ref);

                        // Setter
                        ilgenObjSetter.Emit(OpCodes.Ldarg_0);
                        ilgenObjSetter.Emit(OpCodes.Ldarg_1);
                        ilgenObjSetter.EmitLdc_I4(field.getOffset());
                        ilgenObjSetter.Emit(OpCodes.Ldelem_Ref);
                        fieldType.EmitCheckcast(ilgenObjSetter);
                        fieldType.EmitConvStackTypeToSignatureType(ilgenObjSetter, null);
                        fw.EmitSet(ilgenObjSetter);
                    }
                }
                ilgenObjGetter.Emit(OpCodes.Ret);
                ilgenPrimGetter.Emit(OpCodes.Ret);
                ilgenObjSetter.Emit(OpCodes.Ret);
                ilgenPrimSetter.Emit(OpCodes.Ret);
                ilgenObjGetter.DoEmit();
                ilgenPrimGetter.DoEmit();
                ilgenObjSetter.DoEmit();
                ilgenPrimSetter.DoEmit();
                objFieldGetter  = (ObjFieldGetterSetter)dmObjGetter.CreateDelegate(typeof(ObjFieldGetterSetter));
                primFieldGetter = (PrimFieldGetterSetter)dmPrimGetter.CreateDelegate(typeof(PrimFieldGetterSetter));
                objFieldSetter  = (ObjFieldGetterSetter)dmObjSetter.CreateDelegate(typeof(ObjFieldGetterSetter));
                primFieldSetter = (PrimFieldGetterSetter)dmPrimSetter.CreateDelegate(typeof(PrimFieldGetterSetter));
            }
        }
    private NativeInvokerBytecodeGenerator(LambdaForm lambdaForm, MethodType invokerType)
    {
        if (invokerType != invokerType.basicType())
        {
            throw new BailoutException(Bailout.NotBasicType, invokerType);
        }
        this.lambdaForm   = lambdaForm;
        this.invokerType  = invokerType;
        this.delegateType = MethodHandleUtil.GetMemberWrapperDelegateType(invokerType);
        MethodInfo mi = MethodHandleUtil.GetDelegateInvokeMethod(delegateType);

        Type[] paramTypes = MethodHandleUtil.GetParameterTypes(typeof(object[]), mi);
        // HACK the code we generate is not verifiable (known issue: locals aren't typed correctly), so we stick the DynamicMethod into mscorlib (a security critical assembly)
        this.dm    = new DynamicMethod(lambdaForm.debugName, mi.ReturnType, paramTypes, typeof(object).Module, true);
        this.ilgen = CodeEmitter.Create(this.dm);
        if (invokerType.parameterCount() > MethodHandleUtil.MaxArity)
        {
            this.packedArgType = paramTypes[paramTypes.Length - 1];
            this.packedArgPos  = paramTypes.Length - 1;
        }
        else
        {
            this.packedArgPos = Int32.MaxValue;
        }

        locals = new CodeEmitterLocal[lambdaForm.names.Length];
        for (int i = lambdaForm._arity(); i < lambdaForm.names.Length; i++)
        {
            Name name = lambdaForm.names[i];
            if (name.index() != i)
            {
                throw new BailoutException(Bailout.PreconditionViolated, "name.index() != i");
            }
            switch (name.typeChar())
            {
            case 'L':
                locals[i] = ilgen.DeclareLocal(Types.Object);
                break;

            case 'I':
                locals[i] = ilgen.DeclareLocal(Types.Int32);
                break;

            case 'J':
                locals[i] = ilgen.DeclareLocal(Types.Int64);
                break;

            case 'F':
                locals[i] = ilgen.DeclareLocal(Types.Single);
                break;

            case 'D':
                locals[i] = ilgen.DeclareLocal(Types.Double);
                break;

            case 'V':
                break;

            default:
                throw new BailoutException(Bailout.PreconditionViolated, "Unsupported typeChar(): " + name.typeChar());
            }
        }
    }
    /**
     * Emit bytecode for the guardWithCatch idiom.
     *
     * The pattern looks like (Cf. MethodHandleImpl.makeGuardWithCatch):
     * <blockquote><pre>{@code
     *  guardWithCatch=Lambda(a0:L,a1:L,a2:L,a3:L,a4:L,a5:L,a6:L,a7:L)=>{
     *    t8:L=MethodHandle.invokeBasic(a4:L,a6:L,a7:L);
     *    t9:L=MethodHandleImpl.guardWithCatch(a1:L,a2:L,a3:L,t8:L);
     *   t10:I=MethodHandle.invokeBasic(a5:L,t9:L);t10:I}
     * }</pre></blockquote>
     *
     * It is compiled into bytecode equivalent of the following code:
     * <blockquote><pre>{@code
     *  try {
     *      return a1.invokeBasic(a6, a7);
     *  } catch (Throwable e) {
     *      if (!a2.isInstance(e)) throw e;
     *      return a3.invokeBasic(ex, a6, a7);
     *  }}</pre></blockquote>
     */
    private Name emitGuardWithCatch(int pos)
    {
        Name args    = lambdaForm.names[pos];
        Name invoker = lambdaForm.names[pos + 1];
        Name result  = lambdaForm.names[pos + 2];

        CodeEmitterLabel L_handler = ilgen.DefineLabel();
        CodeEmitterLabel L_done    = ilgen.DefineLabel();

        Class      returnType = result.function._resolvedHandle().type().returnType();
        MethodType type       = args.function._resolvedHandle().type()
                                .dropParameterTypes(0, 1)
                                .changeReturnType(returnType);

        // Normal case
        ilgen.BeginExceptionBlock();
        // load target
        emitPushArgument(invoker, 0);
        emitPushArguments(args, 1); // skip 1st argument: method handle
        EmitInvokeBasic(type.basicType());
        CodeEmitterLocal returnValue = null;

        if (returnType != java.lang.Void.TYPE)
        {
            returnValue = ilgen.DeclareLocal(TypeWrapper.FromClass(returnType).TypeAsLocalOrStackType);
            ilgen.Emit(OpCodes.Stloc, returnValue);
        }
        ilgen.EmitLeave(L_done);

        // Exceptional case
        ilgen.BeginCatchBlock(typeof(Exception));

        // [IKVM] map the exception and store it in a local and exit the handler
        ilgen.EmitLdc_I4(0);
        ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.mapException.MakeGenericMethod(typeof(Exception)));
        CodeEmitterLocal exception = ilgen.DeclareLocal(typeof(Exception));

        ilgen.Emit(OpCodes.Stloc, exception);
        ilgen.EmitLeave(L_handler);
        ilgen.EndExceptionBlock();

        // Check exception's type
        ilgen.MarkLabel(L_handler);
        // load exception class
        emitPushArgument(invoker, 1);
        ilgen.Emit(OpCodes.Ldloc, exception);
        CoreClasses.java.lang.Class.Wrapper.GetMethodWrapper("isInstance", "(Ljava.lang.Object;)Z", false).EmitCall(ilgen);
        CodeEmitterLabel L_rethrow = ilgen.DefineLabel();

        ilgen.EmitBrfalse(L_rethrow);

        // Invoke catcher
        // load catcher
        emitPushArgument(invoker, 2);
        ilgen.Emit(OpCodes.Ldloc, exception);
        emitPushArguments(args, 1); // skip 1st argument: method handle
        MethodType catcherType = type.insertParameterTypes(0, CoreClasses.java.lang.Throwable.Wrapper.ClassObject);

        EmitInvokeBasic(catcherType.basicType());
        if (returnValue != null)
        {
            ilgen.Emit(OpCodes.Stloc, returnValue);
        }
        ilgen.EmitBr(L_done);

        ilgen.MarkLabel(L_rethrow);
        ilgen.Emit(OpCodes.Ldloc, exception);
        ilgen.Emit(OpCodes.Call, Compiler.unmapExceptionMethod);
        ilgen.Emit(OpCodes.Throw);

        ilgen.MarkLabel(L_done);
        if (returnValue != null)
        {
            ilgen.Emit(OpCodes.Ldloc, returnValue);
        }

        return(result);
    }
Exemplo n.º 7
0
 private static void EmitConvert(CodeEmitter ilgen, java.lang.Class srcClass, java.lang.Class dstClass, int level)
 {
     if (srcClass != dstClass)
     {
         TypeWrapper src = TypeWrapper.FromClass(srcClass);
         TypeWrapper dst = TypeWrapper.FromClass(dstClass);
         src.Finish();
         dst.Finish();
         if (src.IsNonPrimitiveValueType)
         {
             src.EmitBox(ilgen);
         }
         if (dst == PrimitiveTypeWrapper.VOID)
         {
             ilgen.Emit(OpCodes.Pop);
         }
         else if (src.IsPrimitive)
         {
             if (dst.IsPrimitive)
             {
                 if (src == PrimitiveTypeWrapper.BYTE)
                 {
                     ilgen.Emit(OpCodes.Conv_I1);
                 }
                 if (dst == PrimitiveTypeWrapper.FLOAT)
                 {
                     ilgen.Emit(OpCodes.Conv_R4);
                 }
                 else if (dst == PrimitiveTypeWrapper.DOUBLE)
                 {
                     ilgen.Emit(OpCodes.Conv_R8);
                 }
                 else if (dst == PrimitiveTypeWrapper.LONG)
                 {
                     if (src == PrimitiveTypeWrapper.FLOAT)
                     {
                         ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.f2l);
                     }
                     else if (src == PrimitiveTypeWrapper.DOUBLE)
                     {
                         ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.d2l);
                     }
                     else
                     {
                         ilgen.Emit(OpCodes.Conv_I8);
                     }
                 }
                 else if (dst == PrimitiveTypeWrapper.BOOLEAN)
                 {
                     if (src == PrimitiveTypeWrapper.FLOAT)
                     {
                         ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.f2i);
                     }
                     else if (src == PrimitiveTypeWrapper.DOUBLE)
                     {
                         ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.d2i);
                     }
                     else
                     {
                         ilgen.Emit(OpCodes.Conv_I4);
                     }
                     ilgen.Emit(OpCodes.Ldc_I4_1);
                     ilgen.Emit(OpCodes.And);
                 }
                 else if (src == PrimitiveTypeWrapper.LONG)
                 {
                     ilgen.Emit(OpCodes.Conv_I4);
                 }
                 else if (src == PrimitiveTypeWrapper.FLOAT)
                 {
                     ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.f2i);
                 }
                 else if (src == PrimitiveTypeWrapper.DOUBLE)
                 {
                     ilgen.Emit(OpCodes.Call, ByteCodeHelperMethods.d2i);
                 }
             }
             else
             {
                 BoxUtil.Box(ilgen, srcClass, dstClass, level);
             }
         }
         else if (src.IsGhost)
         {
             src.EmitConvSignatureTypeToStackType(ilgen);
             EmitConvert(ilgen, [email protected] <java.lang.Object> .Value, dstClass, level);
         }
         else if (srcClass == [email protected] <sun.invoke.empty.Empty> .Value)
         {
             ilgen.Emit(OpCodes.Pop);
             ilgen.Emit(OpCodes.Ldloc, ilgen.DeclareLocal(dst.TypeAsSignatureType));
         }
         else if (dst.IsPrimitive)
         {
             BoxUtil.Unbox(ilgen, srcClass, dstClass, level);
         }
         else if (dst.IsGhost)
         {
             dst.EmitConvStackTypeToSignatureType(ilgen, null);
         }
         else if (dst.IsNonPrimitiveValueType)
         {
             dst.EmitUnbox(ilgen);
         }
         else
         {
             dst.EmitCheckcast(ilgen);
         }
     }
 }