mcs/gmcs/expression.cs

   1 //
   2 // expression.cs: Expression representation for the IL tree.
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //
   7 // (C) 2001, 2002, 2003 Ximian, Inc.
   8 // (C) 2003, 2004 Novell, Inc.
   9 //
  10 #define USE_OLD
  11
  12 namespace Mono.CSharp {
  13         using System;
  14         using System.Collections;
  15         using System.Reflection;
  16         using System.Reflection.Emit;
  17         using System.Text;
  18
  19         /// <summary>
  20         ///   This is just a helper class, it is generated by Unary, UnaryMutator
  21         ///   when an overloaded method has been found.  It just emits the code for a
  22         ///   static call.
  23         /// </summary>
  24         public class StaticCallExpr : ExpressionStatement {
  25                 ArrayList args;
  26                 MethodInfo mi;
  27
  28                 public StaticCallExpr (MethodInfo m, ArrayList a, Location l)
  29                 {
  30                         mi = m;
  31                         args = a;
  32
  33                         type = m.ReturnType;
  34                         eclass = ExprClass.Value;
  35                         loc = l;
  36                 }
  37
  38                 public override Expression DoResolve (EmitContext ec)
  39                 {
  40                         //
  41                         // We are born fully resolved
  42                         //
  43                         return this;
  44                 }
  45
  46                 public override void Emit (EmitContext ec)
  47                 {
  48                         if (args != null)
  49                                 Invocation.EmitArguments (ec, mi, args, false, null);
  50
  51                         ec.ig.Emit (OpCodes.Call, mi);
  52                         return;
  53                 }
  54
  55                 static public StaticCallExpr MakeSimpleCall (EmitContext ec, MethodGroupExpr mg,
  56                                                          Expression e, Location loc)
  57                 {
  58                         ArrayList args;
  59                         MethodBase method;
  60
  61                         args = new ArrayList (1);
  62                         Argument a = new Argument (e, Argument.AType.Expression);
  63
  64                         // We need to resolve the arguments before sending them in !
  65                         if (!a.Resolve (ec, loc))
  66                                 return null;
  67
  68                         args.Add (a);
  69                         method = Invocation.OverloadResolve (
  70                                 ec, (MethodGroupExpr) mg, args, false, loc);
  71
  72                         if (method == null)
  73                                 return null;
  74
  75                         return new StaticCallExpr ((MethodInfo) method, args, loc);
  76                 }
  77
  78                 public override void EmitStatement (EmitContext ec)
  79                 {
  80                         Emit (ec);
  81                         if (TypeManager.TypeToCoreType (type) != TypeManager.void_type)
  82                                 ec.ig.Emit (OpCodes.Pop);
  83                 }
  84
  85                 public MethodInfo Method {
  86                         get { return mi; }
  87                 }
  88         }
  89
  90         public class ParenthesizedExpression : Expression
  91         {
  92                 public Expression Expr;
  93
  94                 public ParenthesizedExpression (Expression expr, Location loc)
  95                 {
  96                         this.Expr = expr;
  97                         this.loc = loc;
  98                 }
  99
 100                 public override Expression DoResolve (EmitContext ec)
 101                 {
 102                         Expr = Expr.Resolve (ec);
 103                         return Expr;
 104                 }
 105
 106                 public override void Emit (EmitContext ec)
 107                 {
 108                         throw new Exception ("Should not happen");
 109                 }
 110         }
 111
 112         /// <summary>
 113         ///   Unary expressions.
 114         /// </summary>
 115         ///
 116         /// <remarks>
 117         ///   Unary implements unary expressions.   It derives from
 118         ///   ExpressionStatement becuase the pre/post increment/decrement
 119         ///   operators can be used in a statement context.
 120         /// </remarks>
 121         public class Unary : Expression {
 122                 public enum Operator : byte {
 123                         UnaryPlus, UnaryNegation, LogicalNot, OnesComplement,
 124                         Indirection, AddressOf,  TOP
 125                 }
 126
 127                 public Operator Oper;
 128                 public Expression Expr;
 129
 130                 public Unary (Operator op, Expression expr, Location loc)
 131                 {
 132                         this.Oper = op;
 133                         this.Expr = expr;
 134                         this.loc = loc;
 135                 }
 136
 137                 /// <summary>
 138                 ///   Returns a stringified representation of the Operator
 139                 /// </summary>
 140                 static public string OperName (Operator oper)
 141                 {
 142                         switch (oper){
 143                         case Operator.UnaryPlus:
 144                                 return "+";
 145                         case Operator.UnaryNegation:
 146                                 return "-";
 147                         case Operator.LogicalNot:
 148                                 return "!";
 149                         case Operator.OnesComplement:
 150                                 return "~";
 151                         case Operator.AddressOf:
 152                                 return "&";
 153                         case Operator.Indirection:
 154                                 return "*";
 155                         }
 156
 157                         return oper.ToString ();
 158                 }
 159
 160                 public static readonly string [] oper_names;
 161
 162                 static Unary ()
 163                 {
 164                         oper_names = new string [(int)Operator.TOP];
 165
 166                         oper_names [(int) Operator.UnaryPlus] = "op_UnaryPlus";
 167                         oper_names [(int) Operator.UnaryNegation] = "op_UnaryNegation";
 168                         oper_names [(int) Operator.LogicalNot] = "op_LogicalNot";
 169                         oper_names [(int) Operator.OnesComplement] = "op_OnesComplement";
 170                         oper_names [(int) Operator.Indirection] = "op_Indirection";
 171                         oper_names [(int) Operator.AddressOf] = "op_AddressOf";
 172                 }
 173
 174                 void Error23 (Type t)
 175                 {
 176                         Error (
 177                                 23, "Operator " + OperName (Oper) +
 178                                 " cannot be applied to operand of type `" +
 179                                 TypeManager.CSharpName (t) + "'");
 180                 }
 181
 182                 /// <remarks>
 183                 ///   The result has been already resolved:
 184                 ///
 185                 ///   FIXME: a minus constant -128 sbyte cant be turned into a
 186                 ///   constant byte.
 187                 /// </remarks>
 188                 static Expression TryReduceNegative (Constant expr)
 189                 {
 190                         Expression e = null;
 191
 192                         if (expr is IntConstant)
 193                                 e = new IntConstant (-((IntConstant) expr).Value);
 194                         else if (expr is UIntConstant){
 195                                 uint value = ((UIntConstant) expr).Value;
 196
 197                                 if (value < 2147483649)
 198                                         return new IntConstant (-(int)value);
 199                                 else
 200                                         e = new LongConstant (-value);
 201                         }
 202                         else if (expr is LongConstant)
 203                                 e = new LongConstant (-((LongConstant) expr).Value);
 204                         else if (expr is ULongConstant){
 205                                 ulong value = ((ULongConstant) expr).Value;
 206
 207                                 if (value < 9223372036854775809)
 208                                         return new LongConstant(-(long)value);
 209                         }
 210                         else if (expr is FloatConstant)
 211                                 e = new FloatConstant (-((FloatConstant) expr).Value);
 212                         else if (expr is DoubleConstant)
 213                                 e = new DoubleConstant (-((DoubleConstant) expr).Value);
 214                         else if (expr is DecimalConstant)
 215                                 e = new DecimalConstant (-((DecimalConstant) expr).Value);
 216                         else if (expr is ShortConstant)
 217                                 e = new IntConstant (-((ShortConstant) expr).Value);
 218                         else if (expr is UShortConstant)
 219                                 e = new IntConstant (-((UShortConstant) expr).Value);
 220                         else if (expr is SByteConstant)
 221                                 e = new IntConstant (-((SByteConstant) expr).Value);
 222                         else if (expr is ByteConstant)
 223                                 e = new IntConstant (-((ByteConstant) expr).Value);
 224                         return e;
 225                 }
 226
 227                 // <summary>
 228                 //   This routine will attempt to simplify the unary expression when the
 229                 //   argument is a constant.  The result is returned in `result' and the
 230                 //   function returns true or false depending on whether a reduction
 231                 //   was performed or not
 232                 // </summary>
 233                 bool Reduce (EmitContext ec, Constant e, out Expression result)
 234                 {
 235                         Type expr_type = e.Type;
 236
 237                         switch (Oper){
 238                         case Operator.UnaryPlus:
 239                                 result = e;
 240                                 return true;
 241
 242                         case Operator.UnaryNegation:
 243                                 result = TryReduceNegative (e);
 244                                 return result != null;
 245
 246                         case Operator.LogicalNot:
 247                                 if (expr_type != TypeManager.bool_type) {
 248                                         result = null;
 249                                         Error23 (expr_type);
 250                                         return false;
 251                                 }
 252
 253                                 BoolConstant b = (BoolConstant) e;
 254                                 result = new BoolConstant (!(b.Value));
 255                                 return true;
 256
 257                         case Operator.OnesComplement:
 258                                 if (!((expr_type == TypeManager.int32_type) ||
 259                                       (expr_type == TypeManager.uint32_type) ||
 260                                       (expr_type == TypeManager.int64_type) ||
 261                                       (expr_type == TypeManager.uint64_type) ||
 262                                       (expr_type.IsSubclassOf (TypeManager.enum_type)))){
 263
 264                                         result = null;
 265                                         if (Convert.ImplicitConversionExists (ec, e, TypeManager.int32_type)){
 266                                                 result = new Cast (new TypeExpression (TypeManager.int32_type, loc), e, loc);
 267                                                 result = result.Resolve (ec);
 268                                         } else if (Convert.ImplicitConversionExists (ec, e, TypeManager.uint32_type)){
 269                                                 result = new Cast (new TypeExpression (TypeManager.uint32_type, loc), e, loc);
 270                                                 result = result.Resolve (ec);
 271                                         } else if (Convert.ImplicitConversionExists (ec, e, TypeManager.int64_type)){
 272                                                 result = new Cast (new TypeExpression (TypeManager.int64_type, loc), e, loc);
 273                                                 result = result.Resolve (ec);
 274                                         } else if (Convert.ImplicitConversionExists (ec, e, TypeManager.uint64_type)){
 275                                                 result = new Cast (new TypeExpression (TypeManager.uint64_type, loc), e, loc);
 276                                                 result = result.Resolve (ec);
 277                                         }
 278
 279                                         if (result == null || !(result is Constant)){
 280                                                 result = null;
 281                                                 Error23 (expr_type);
 282                                                 return false;
 283                                         }
 284
 285                                         expr_type = result.Type;
 286                                         e = (Constant) result;
 287                                 }
 288
 289                                 if (e is EnumConstant){
 290                                         EnumConstant enum_constant = (EnumConstant) e;
 291                                         Expression reduced;
 292
 293                                         if (Reduce (ec, enum_constant.Child, out reduced)){
 294                                                 result = new EnumConstant ((Constant) reduced, enum_constant.Type);
 295                                                 return true;
 296                                         } else {
 297                                                 result = null;
 298                                                 return false;
 299                                         }
 300                                 }
 301
 302                                 if (expr_type == TypeManager.int32_type){
 303                                         result = new IntConstant (~ ((IntConstant) e).Value);
 304                                 } else if (expr_type == TypeManager.uint32_type){
 305                                         result = new UIntConstant (~ ((UIntConstant) e).Value);
 306                                 } else if (expr_type == TypeManager.int64_type){
 307                                         result = new LongConstant (~ ((LongConstant) e).Value);
 308                                 } else if (expr_type == TypeManager.uint64_type){
 309                                         result = new ULongConstant (~ ((ULongConstant) e).Value);
 310                                 } else {
 311                                         result = null;
 312                                         Error23 (expr_type);
 313                                         return false;
 314                                 }
 315                                 return true;
 316
 317                         case Operator.AddressOf:
 318                                 result = this;
 319                                 return false;
 320
 321                         case Operator.Indirection:
 322                                 result = this;
 323                                 return false;
 324                         }
 325                         throw new Exception ("Can not constant fold: " + Oper.ToString());
 326                 }
 327
 328                 Expression ResolveOperator (EmitContext ec)
 329                 {
 330                         //
 331                         // Step 1: Default operations on CLI native types.
 332                         //
 333
 334                         // Attempt to use a constant folding operation.
 335                         if (Expr is Constant){
 336                                 Expression result;
 337
 338                                 if (Reduce (ec, (Constant) Expr, out result))
 339                                         return result;
 340                         }
 341
 342                         //
 343                         // Step 2: Perform Operator Overload location
 344                         //
 345                         Type expr_type = Expr.Type;
 346                         Expression mg;
 347                         string op_name;
 348
 349                         op_name = oper_names [(int) Oper];
 350
 351                         mg = MemberLookup (ec, expr_type, op_name, MemberTypes.Method, AllBindingFlags, loc);
 352
 353                         if (mg != null) {
 354                                 Expression e = StaticCallExpr.MakeSimpleCall (
 355                                         ec, (MethodGroupExpr) mg, Expr, loc);
 356
 357                                 if (e == null){
 358                                         Error23 (expr_type);
 359                                         return null;
 360                                 }
 361
 362                                 return e;
 363                         }
 364
 365                         // Only perform numeric promotions on:
 366                         // +, -
 367
 368                         if (expr_type == null)
 369                                 return null;
 370
 371                         switch (Oper){
 372                         case Operator.LogicalNot:
 373                                 if (expr_type != TypeManager.bool_type) {
 374                                         Expr = ResolveBoolean (ec, Expr, loc);
 375                                         if (Expr == null){
 376                                                 Error23 (expr_type);
 377                                                 return null;
 378                                         }
 379                                 }
 380
 381                                 type = TypeManager.bool_type;
 382                                 return this;
 383
 384                         case Operator.OnesComplement:
 385                                 if (!((expr_type == TypeManager.int32_type) ||
 386                                       (expr_type == TypeManager.uint32_type) ||
 387                                       (expr_type == TypeManager.int64_type) ||
 388                                       (expr_type == TypeManager.uint64_type) ||
 389                                       (expr_type.IsSubclassOf (TypeManager.enum_type)))){
 390                                         Expression e;
 391
 392                                         e = Convert.ImplicitConversion (ec, Expr, TypeManager.int32_type, loc);
 393                                         if (e != null){
 394                                                 type = TypeManager.int32_type;
 395                                                 return this;
 396                                         }
 397                                         e = Convert.ImplicitConversion (ec, Expr, TypeManager.uint32_type, loc);
 398                                         if (e != null){
 399                                                 type = TypeManager.uint32_type;
 400                                                 return this;
 401                                         }
 402                                         e = Convert.ImplicitConversion (ec, Expr, TypeManager.int64_type, loc);
 403                                         if (e != null){
 404                                                 type = TypeManager.int64_type;
 405                                                 return this;
 406                                         }
 407                                         e = Convert.ImplicitConversion (ec, Expr, TypeManager.uint64_type, loc);
 408                                         if (e != null){
 409                                                 type = TypeManager.uint64_type;
 410                                                 return this;
 411                                         }
 412                                         Error23 (expr_type);
 413                                         return null;
 414                                 }
 415                                 type = expr_type;
 416                                 return this;
 417
 418                         case Operator.AddressOf:
 419                                 if (!ec.InUnsafe) {
 420                                         UnsafeError (loc);
 421                                         return null;
 422                                 }
 423
 424                                 if (!TypeManager.VerifyUnManaged (Expr.Type, loc)){
 425                                         return null;
 426                                 }
 427
 428                                 IVariable variable = Expr as IVariable;
 429                                 bool is_fixed = variable != null && variable.VerifyFixed (false);
 430
 431                                 if (!ec.InFixedInitializer && !is_fixed) {
 432                                         Error (212, "You can only take the address of an unfixed expression inside " +
 433                                                "of a fixed statement initializer");
 434                                         return null;
 435                                 }
 436
 437                                 if (ec.InFixedInitializer && is_fixed) {
 438                                         Error (213, "You can not fix an already fixed expression");
 439                                         return null;
 440                                 }
 441
 442                                 LocalVariableReference lr = Expr as LocalVariableReference;
 443                                 if (lr != null){
 444                                         if (lr.local_info.IsCaptured){
 445                                                 AnonymousMethod.Error_AddressOfCapturedVar (lr.Name, loc);
 446                                                 return null;
 447                                         }
 448                                         lr.local_info.AddressTaken = true;
 449                                         lr.local_info.Used = true;
 450                                 }
 451
 452                                 // According to the specs, a variable is considered definitely assigned if you take
 453                                 // its address.
 454                                 if ((variable != null) && (variable.VariableInfo != null))
 455                                         variable.VariableInfo.SetAssigned (ec);
 456
 457                                 type = TypeManager.GetPointerType (Expr.Type);
 458                                 return this;
 459
 460                         case Operator.Indirection:
 461                                 if (!ec.InUnsafe){
 462                                         UnsafeError (loc);
 463                                         return null;
 464                                 }
 465
 466                                 if (!expr_type.IsPointer){
 467                                         Error (193, "The * or -> operator can only be applied to pointers");
 468                                         return null;
 469                                 }
 470
 471                                 //
 472                                 // We create an Indirection expression, because
 473                                 // it can implement the IMemoryLocation.
 474                                 //
 475                                 return new Indirection (Expr, loc);
 476
 477                         case Operator.UnaryPlus:
 478                                 //
 479                                 // A plus in front of something is just a no-op, so return the child.
 480                                 //
 481                                 return Expr;
 482
 483                         case Operator.UnaryNegation:
 484                                 //
 485                                 // Deals with -literals
 486                                 // int     operator- (int x)
 487                                 // long    operator- (long x)
 488                                 // float   operator- (float f)
 489                                 // double  operator- (double d)
 490                                 // decimal operator- (decimal d)
 491                                 //
 492                                 Expression expr = null;
 493
 494                                 //
 495                                 // transform - - expr into expr
 496                                 //
 497                                 if (Expr is Unary){
 498                                         Unary unary = (Unary) Expr;
 499
 500                                         if (unary.Oper == Operator.UnaryNegation)
 501                                                 return unary.Expr;
 502                                 }
 503
 504                                 //
 505                                 // perform numeric promotions to int,
 506                                 // long, double.
 507                                 //
 508                                 //
 509                                 // The following is inneficient, because we call
 510                                 // ImplicitConversion too many times.
 511                                 //
 512                                 // It is also not clear if we should convert to Float
 513                                 // or Double initially.
 514                                 //
 515                                 if (expr_type == TypeManager.uint32_type){
 516                                         //
 517                                         // FIXME: handle exception to this rule that
 518                                         // permits the int value -2147483648 (-2^31) to
 519                                         // bt wrote as a decimal interger literal
 520                                         //
 521                                         type = TypeManager.int64_type;
 522                                         Expr = Convert.ImplicitConversion (ec, Expr, type, loc);
 523                                         return this;
 524                                 }
 525
 526                                 if (expr_type == TypeManager.uint64_type){
 527                                         //
 528                                         // FIXME: Handle exception of `long value'
 529                                         // -92233720368547758087 (-2^63) to be wrote as
 530                                         // decimal integer literal.
 531                                         //
 532                                         Error23 (expr_type);
 533                                         return null;
 534                                 }
 535
 536                                 if (expr_type == TypeManager.float_type){
 537                                         type = expr_type;
 538                                         return this;
 539                                 }
 540
 541                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.int32_type, loc);
 542                                 if (expr != null){
 543                                         Expr = expr;
 544                                         type = expr.Type;
 545                                         return this;
 546                                 }
 547
 548                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.int64_type, loc);
 549                                 if (expr != null){
 550                                         Expr = expr;
 551                                         type = expr.Type;
 552                                         return this;
 553                                 }
 554
 555                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.double_type, loc);
 556                                 if (expr != null){
 557                                         Expr = expr;
 558                                         type = expr.Type;
 559                                         return this;
 560                                 }
 561
 562                                 Error23 (expr_type);
 563                                 return null;
 564                         }
 565
 566                         Error (187, "No such operator '" + OperName (Oper) + "' defined for type '" +
 567                                TypeManager.CSharpName (expr_type) + "'");
 568                         return null;
 569                 }
 570
 571                 public override Expression DoResolve (EmitContext ec)
 572                 {
 573                         if (Oper == Operator.AddressOf) {
 574                                 Expr = Expr.DoResolveLValue (ec, new EmptyExpression ());
 575
 576                                 if (Expr == null || Expr.eclass != ExprClass.Variable){
 577                                         Error (211, "Cannot take the address of non-variables");
 578                                         return null;
 579                                 }
 580                         }
 581                         else
 582                                 Expr = Expr.Resolve (ec);
 583
 584                         if (Expr == null)
 585                                 return null;
 586
 587                         if (TypeManager.IsNullableType (Expr.Type))
 588                                 return new Nullable.LiftedUnaryOperator (Oper, Expr, loc).Resolve (ec);
 589
 590                         eclass = ExprClass.Value;
 591                         return ResolveOperator (ec);
 592                 }
 593
 594                 public override Expression DoResolveLValue (EmitContext ec, Expression right)
 595                 {
 596                         if (Oper == Operator.Indirection)
 597                                 return DoResolve (ec);
 598
 599                         return null;
 600                 }
 601
 602                 public override void Emit (EmitContext ec)
 603                 {
 604                         ILGenerator ig = ec.ig;
 605
 606                         switch (Oper) {
 607                         case Operator.UnaryPlus:
 608                                 throw new Exception ("This should be caught by Resolve");
 609
 610                         case Operator.UnaryNegation:
 611                                 if (ec.CheckState) {
 612                                         ig.Emit (OpCodes.Ldc_I4_0);
 613                                         if (type == TypeManager.int64_type)
 614                                                 ig.Emit (OpCodes.Conv_U8);
 615                                         Expr.Emit (ec);
 616                                         ig.Emit (OpCodes.Sub_Ovf);
 617                                 } else {
 618                                 Expr.Emit (ec);
 619                                 ig.Emit (OpCodes.Neg);
 620                                 }
 621
 622                                 break;
 623
 624                         case Operator.LogicalNot:
 625                                 Expr.Emit (ec);
 626                                 ig.Emit (OpCodes.Ldc_I4_0);
 627                                 ig.Emit (OpCodes.Ceq);
 628                                 break;
 629
 630                         case Operator.OnesComplement:
 631                                 Expr.Emit (ec);
 632                                 ig.Emit (OpCodes.Not);
 633                                 break;
 634
 635                         case Operator.AddressOf:
 636                                 ((IMemoryLocation)Expr).AddressOf (ec, AddressOp.LoadStore);
 637                                 break;
 638
 639                         default:
 640                                 throw new Exception ("This should not happen: Operator = "
 641                                                      + Oper.ToString ());
 642                         }
 643                 }
 644
 645                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
 646                 {
 647                         if (Oper == Operator.LogicalNot)
 648                                 Expr.EmitBranchable (ec, target, !onTrue);
 649                         else
 650                                 base.EmitBranchable (ec, target, onTrue);
 651                 }
 652
 653                 public override string ToString ()
 654                 {
 655                         return "Unary (" + Oper + ", " + Expr + ")";
 656                 }
 657
 658         }
 659
 660         //
 661         // Unary operators are turned into Indirection expressions
 662         // after semantic analysis (this is so we can take the address
 663         // of an indirection).
 664         //
 665         public class Indirection : Expression, IMemoryLocation, IAssignMethod, IVariable {
 666                 Expression expr;
 667                 LocalTemporary temporary;
 668                 bool prepared;
 669
 670                 public Indirection (Expression expr, Location l)
 671                 {
 672                         this.expr = expr;
 673                         type = TypeManager.HasElementType (expr.Type) ? TypeManager.GetElementType (expr.Type) : expr.Type;
 674                         eclass = ExprClass.Variable;
 675                         loc = l;
 676                 }
 677
 678                 public override void Emit (EmitContext ec)
 679                 {
 680                         if (!prepared)
 681                                 expr.Emit (ec);
 682
 683                         LoadFromPtr (ec.ig, Type);
 684                 }
 685
 686                 public void Emit (EmitContext ec, bool leave_copy)
 687                 {
 688                         Emit (ec);
 689                         if (leave_copy) {
 690                                 ec.ig.Emit (OpCodes.Dup);
 691                                 temporary = new LocalTemporary (ec, expr.Type);
 692                                 temporary.Store (ec);
 693                         }
 694                 }
 695
 696                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
 697                 {
 698                         prepared = prepare_for_load;
 699
 700                         expr.Emit (ec);
 701
 702                         if (prepare_for_load)
 703                                 ec.ig.Emit (OpCodes.Dup);
 704
 705                         source.Emit (ec);
 706                         if (leave_copy) {
 707                                 ec.ig.Emit (OpCodes.Dup);
 708                                 temporary = new LocalTemporary (ec, expr.Type);
 709                                 temporary.Store (ec);
 710                         }
 711
 712                         StoreFromPtr (ec.ig, type);
 713
 714                         if (temporary != null)
 715                                 temporary.Emit (ec);
 716                 }
 717
 718                 public void AddressOf (EmitContext ec, AddressOp Mode)
 719                 {
 720                         expr.Emit (ec);
 721                 }
 722
 723                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
 724                 {
 725                         return DoResolve (ec);
 726                 }
 727
 728                 public override Expression DoResolve (EmitContext ec)
 729                 {
 730                         //
 731                         // Born fully resolved
 732                         //
 733                         return this;
 734                 }
 735
 736                 public override string ToString ()
 737                 {
 738                         return "*(" + expr + ")";
 739                 }
 740
 741                 #region IVariable Members
 742
 743                 public VariableInfo VariableInfo {
 744                         get {
 745                                 return null;
 746                         }
 747                 }
 748
 749                 public bool VerifyFixed (bool is_expression)
 750                 {
 751                         return true;
 752                 }
 753
 754                 #endregion
 755         }
 756
 757         /// <summary>
 758         ///   Unary Mutator expressions (pre and post ++ and --)
 759         /// </summary>
 760         ///
 761         /// <remarks>
 762         ///   UnaryMutator implements ++ and -- expressions.   It derives from
 763         ///   ExpressionStatement becuase the pre/post increment/decrement
 764         ///   operators can be used in a statement context.
 765         ///
 766         /// FIXME: Idea, we could split this up in two classes, one simpler
 767         /// for the common case, and one with the extra fields for more complex
 768         /// classes (indexers require temporary access;  overloaded require method)
 769         ///
 770         /// </remarks>
 771         public class UnaryMutator : ExpressionStatement {
 772                 [Flags]
 773                 public enum Mode : byte {
 774                         IsIncrement    = 0,
 775                         IsDecrement    = 1,
 776                         IsPre          = 0,
 777                         IsPost         = 2,
 778
 779                         PreIncrement   = 0,
 780                         PreDecrement   = IsDecrement,
 781                         PostIncrement  = IsPost,
 782                         PostDecrement  = IsPost | IsDecrement
 783                 }
 784
 785                 Mode mode;
 786                 bool is_expr = false;
 787                 bool recurse = false;
 788
 789                 Expression expr;
 790
 791                 //
 792                 // This is expensive for the simplest case.
 793                 //
 794                 StaticCallExpr method;
 795
 796                 public UnaryMutator (Mode m, Expression e, Location l)
 797                 {
 798                         mode = m;
 799                         loc = l;
 800                         expr = e;
 801                 }
 802
 803                 static string OperName (Mode mode)
 804                 {
 805                         return (mode == Mode.PreIncrement || mode == Mode.PostIncrement) ?
 806                                 "++" : "--";
 807                 }
 808
 809                 /// <summary>
 810                 ///   Returns whether an object of type `t' can be incremented
 811                 ///   or decremented with add/sub (ie, basically whether we can
 812                 ///   use pre-post incr-decr operations on it, but it is not a
 813                 ///   System.Decimal, which we require operator overloading to catch)
 814                 /// </summary>
 815                 static bool IsIncrementableNumber (Type t)
 816                 {
 817                         return (t == TypeManager.sbyte_type) ||
 818                                 (t == TypeManager.byte_type) ||
 819                                 (t == TypeManager.short_type) ||
 820                                 (t == TypeManager.ushort_type) ||
 821                                 (t == TypeManager.int32_type) ||
 822                                 (t == TypeManager.uint32_type) ||
 823                                 (t == TypeManager.int64_type) ||
 824                                 (t == TypeManager.uint64_type) ||
 825                                 (t == TypeManager.char_type) ||
 826                                 (t.IsSubclassOf (TypeManager.enum_type)) ||
 827                                 (t == TypeManager.float_type) ||
 828                                 (t == TypeManager.double_type) ||
 829                                 (t.IsPointer && t != TypeManager.void_ptr_type);
 830                 }
 831
 832                 Expression ResolveOperator (EmitContext ec)
 833                 {
 834                         Type expr_type = expr.Type;
 835
 836                         //
 837                         // Step 1: Perform Operator Overload location
 838                         //
 839                         Expression mg;
 840                         string op_name;
 841
 842                         if (mode == Mode.PreIncrement || mode == Mode.PostIncrement)
 843                                 op_name = "op_Increment";
 844                         else
 845                                 op_name = "op_Decrement";
 846
 847                         mg = MemberLookup (ec, expr_type, op_name, MemberTypes.Method, AllBindingFlags, loc);
 848
 849                         if (mg != null) {
 850                                 method = StaticCallExpr.MakeSimpleCall (
 851                                         ec, (MethodGroupExpr) mg, expr, loc);
 852
 853                                 type = method.Type;
 854                         } else if (!IsIncrementableNumber (expr_type)) {
 855                                 Error (187, "No such operator '" + OperName (mode) + "' defined for type '" +
 856                                        TypeManager.CSharpName (expr_type) + "'");
 857                                    return null;
 858                         }
 859
 860                         //
 861                         // The operand of the prefix/postfix increment decrement operators
 862                         // should be an expression that is classified as a variable,
 863                         // a property access or an indexer access
 864                         //
 865                         type = expr_type;
 866                         if (expr.eclass == ExprClass.Variable){
 867                                 LocalVariableReference var = expr as LocalVariableReference;
 868                                 if ((var != null) && var.IsReadOnly) {
 869                                         Error (1604, "cannot assign to `" + var.Name + "' because it is readonly");
 870                                         return null;
 871                                 }
 872                         } else if (expr.eclass == ExprClass.IndexerAccess || expr.eclass == ExprClass.PropertyAccess){
 873                                 expr = expr.ResolveLValue (ec, this);
 874                                 if (expr == null)
 875                                         return null;
 876                         } else {
 877                                 expr.Error_UnexpectedKind ("variable, indexer or property access", loc);
 878                                 return null;
 879                         }
 880
 881                         return this;
 882                 }
 883
 884                 public override Expression DoResolve (EmitContext ec)
 885                 {
 886                         expr = expr.Resolve (ec);
 887
 888                         if (expr == null)
 889                                 return null;
 890
 891                         eclass = ExprClass.Value;
 892
 893                         if (TypeManager.IsNullableType (expr.Type))
 894                                 return new Nullable.LiftedUnaryMutator (mode, expr, loc).Resolve (ec);
 895
 896                         return ResolveOperator (ec);
 897                 }
 898
 899                 static int PtrTypeSize (Type t)
 900                 {
 901                         return GetTypeSize (TypeManager.GetElementType (t));
 902                 }
 903
 904                 //
 905                 // Loads the proper "1" into the stack based on the type, then it emits the
 906                 // opcode for the operation requested
 907                 //
 908                 void LoadOneAndEmitOp (EmitContext ec, Type t)
 909                 {
 910                         //
 911                         // Measure if getting the typecode and using that is more/less efficient
 912                         // that comparing types.  t.GetTypeCode() is an internal call.
 913                         //
 914                         ILGenerator ig = ec.ig;
 915
 916                         if (t == TypeManager.uint64_type || t == TypeManager.int64_type)
 917                                 LongConstant.EmitLong (ig, 1);
 918                         else if (t == TypeManager.double_type)
 919                                 ig.Emit (OpCodes.Ldc_R8, 1.0);
 920                         else if (t == TypeManager.float_type)
 921                                 ig.Emit (OpCodes.Ldc_R4, 1.0F);
 922                         else if (t.IsPointer){
 923                                 int n = PtrTypeSize (t);
 924
 925                                 if (n == 0)
 926                                         ig.Emit (OpCodes.Sizeof, t);
 927                                 else
 928                                         IntConstant.EmitInt (ig, n);
 929                         } else
 930                                 ig.Emit (OpCodes.Ldc_I4_1);
 931
 932                         //
 933                         // Now emit the operation
 934                         //
 935                         if (ec.CheckState){
 936                                 if (t == TypeManager.int32_type ||
 937                                     t == TypeManager.int64_type){
 938                                         if ((mode & Mode.IsDecrement) != 0)
 939                                                 ig.Emit (OpCodes.Sub_Ovf);
 940                                         else
 941                                                 ig.Emit (OpCodes.Add_Ovf);
 942                                 } else if (t == TypeManager.uint32_type ||
 943                                            t == TypeManager.uint64_type){
 944                                         if ((mode & Mode.IsDecrement) != 0)
 945                                                 ig.Emit (OpCodes.Sub_Ovf_Un);
 946                                         else
 947                                                 ig.Emit (OpCodes.Add_Ovf_Un);
 948                                 } else {
 949                                         if ((mode & Mode.IsDecrement) != 0)
 950                                                 ig.Emit (OpCodes.Sub_Ovf);
 951                                         else
 952                                                 ig.Emit (OpCodes.Add_Ovf);
 953                                 }
 954                         } else {
 955                                 if ((mode & Mode.IsDecrement) != 0)
 956                                         ig.Emit (OpCodes.Sub);
 957                                 else
 958                                         ig.Emit (OpCodes.Add);
 959                         }
 960
 961                         if (t == TypeManager.sbyte_type){
 962                                 if (ec.CheckState)
 963                                         ig.Emit (OpCodes.Conv_Ovf_I1);
 964                                 else
 965                                         ig.Emit (OpCodes.Conv_I1);
 966                         } else if (t == TypeManager.byte_type){
 967                                 if (ec.CheckState)
 968                                         ig.Emit (OpCodes.Conv_Ovf_U1);
 969                                 else
 970                                         ig.Emit (OpCodes.Conv_U1);
 971                         } else if (t == TypeManager.short_type){
 972                                 if (ec.CheckState)
 973                                         ig.Emit (OpCodes.Conv_Ovf_I2);
 974                                 else
 975                                         ig.Emit (OpCodes.Conv_I2);
 976                         } else if (t == TypeManager.ushort_type || t == TypeManager.char_type){
 977                                 if (ec.CheckState)
 978                                         ig.Emit (OpCodes.Conv_Ovf_U2);
 979                                 else
 980                                         ig.Emit (OpCodes.Conv_U2);
 981                         }
 982
 983                 }
 984
 985                 void EmitCode (EmitContext ec, bool is_expr)
 986                 {
 987                         recurse = true;
 988                         this.is_expr = is_expr;
 989                         ((IAssignMethod) expr).EmitAssign (ec, this, is_expr && (mode == Mode.PreIncrement || mode == Mode.PreDecrement), true);
 990                 }
 991
 992                 public override void Emit (EmitContext ec)
 993                 {
 994                         //
 995                         // We use recurse to allow ourselfs to be the source
 996                         // of an assignment. This little hack prevents us from
 997                         // having to allocate another expression
 998                         //
 999                         if (recurse) {
1000                                 ((IAssignMethod) expr).Emit (ec, is_expr && (mode == Mode.PostIncrement  || mode == Mode.PostDecrement));
1001                                 if (method == null)
1002                                         LoadOneAndEmitOp (ec, expr.Type);
1003                                 else
1004                                         ec.ig.Emit (OpCodes.Call, method.Method);
1005                                 recurse = false;
1006                                 return;
1007                         }
1008
1009                         EmitCode (ec, true);
1010                 }
1011
1012                 public override void EmitStatement (EmitContext ec)
1013                 {
1014                         EmitCode (ec, false);
1015                 }
1016         }
1017
1018         /// <summary>
1019         ///   Base class for the `Is' and `As' classes.
1020         /// </summary>
1021         ///
1022         /// <remarks>
1023         ///   FIXME: Split this in two, and we get to save the `Operator' Oper
1024         ///   size.
1025         /// </remarks>
1026         public abstract class Probe : Expression {
1027                 public Expression ProbeType;
1028                 protected Expression expr;
1029                 protected Type probe_type;
1030
1031                 public Probe (Expression expr, Expression probe_type, Location l)
1032                 {
1033                         ProbeType = probe_type;
1034                         loc = l;
1035                         this.expr = expr;
1036                 }
1037
1038                 public Expression Expr {
1039                         get {
1040                                 return expr;
1041                         }
1042                 }
1043
1044                 public override Expression DoResolve (EmitContext ec)
1045                 {
1046                         TypeExpr texpr = ProbeType.ResolveAsTypeTerminal (ec);
1047                         if (texpr == null)
1048                                 return null;
1049                         probe_type = texpr.Type;
1050
1051                         CheckObsoleteAttribute (probe_type);
1052
1053                         expr = expr.Resolve (ec);
1054                         if (expr == null)
1055                                 return null;
1056
1057                         if (expr.Type.IsPointer) {
1058                                 Report.Error (244, loc, "\"is\" or \"as\" are not valid on pointer types");
1059                                 return null;
1060                         }
1061                         return this;
1062                 }
1063         }
1064
1065         /// <summary>
1066         ///   Implementation of the `is' operator.
1067         /// </summary>
1068         public class Is : Probe {
1069                 public Is (Expression expr, Expression probe_type, Location l)
1070                         : base (expr, probe_type, l)
1071                 {
1072                 }
1073
1074                 enum Action {
1075                         AlwaysTrue, AlwaysNull, AlwaysFalse, LeaveOnStack, Probe
1076                 }
1077
1078                 Action action;
1079
1080                 public override void Emit (EmitContext ec)
1081                 {
1082                         ILGenerator ig = ec.ig;
1083
1084                         expr.Emit (ec);
1085
1086                         switch (action){
1087                         case Action.AlwaysFalse:
1088                                 ig.Emit (OpCodes.Pop);
1089                                 IntConstant.EmitInt (ig, 0);
1090                                 return;
1091                         case Action.AlwaysTrue:
1092                                 ig.Emit (OpCodes.Pop);
1093                                 IntConstant.EmitInt (ig, 1);
1094                                 return;
1095                         case Action.LeaveOnStack:
1096                                 // the `e != null' rule.
1097                                 ig.Emit (OpCodes.Ldnull);
1098                                 ig.Emit (OpCodes.Ceq);
1099                                 ig.Emit (OpCodes.Ldc_I4_0);
1100                                 ig.Emit (OpCodes.Ceq);
1101                                 return;
1102                         case Action.Probe:
1103                                 ig.Emit (OpCodes.Isinst, probe_type);
1104                                 ig.Emit (OpCodes.Ldnull);
1105                                 ig.Emit (OpCodes.Cgt_Un);
1106                                 return;
1107                         }
1108                         throw new Exception ("never reached");
1109                 }
1110
1111                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
1112                 {
1113                         ILGenerator ig = ec.ig;
1114
1115                         switch (action){
1116                         case Action.AlwaysFalse:
1117                                 if (! onTrue)
1118                                         ig.Emit (OpCodes.Br, target);
1119
1120                                 return;
1121                         case Action.AlwaysTrue:
1122                                 if (onTrue)
1123                                         ig.Emit (OpCodes.Br, target);
1124
1125                                 return;
1126                         case Action.LeaveOnStack:
1127                                 // the `e != null' rule.
1128                                 expr.Emit (ec);
1129                                 ig.Emit (onTrue ? OpCodes.Brtrue : OpCodes.Brfalse, target);
1130                                 return;
1131                         case Action.Probe:
1132                                 expr.Emit (ec);
1133                                 ig.Emit (OpCodes.Isinst, probe_type);
1134                                 ig.Emit (onTrue ? OpCodes.Brtrue : OpCodes.Brfalse, target);
1135                                 return;
1136                         }
1137                         throw new Exception ("never reached");
1138                 }
1139
1140                 public override Expression DoResolve (EmitContext ec)
1141                 {
1142                         Expression e = base.DoResolve (ec);
1143
1144                         if ((e == null) || (expr == null))
1145                                 return null;
1146
1147                         Type etype = expr.Type;
1148                         bool warning_always_matches = false;
1149                         bool warning_never_matches = false;
1150
1151                         type = TypeManager.bool_type;
1152                         eclass = ExprClass.Value;
1153
1154                         //
1155                         // First case, if at compile time, there is an implicit conversion
1156                         // then e != null (objects) or true (value types)
1157                         //
1158                         e = Convert.ImplicitConversionStandard (ec, expr, probe_type, loc);
1159                         if (e != null){
1160                                 expr = e;
1161                                 if (etype.IsValueType)
1162                                         action = Action.AlwaysTrue;
1163                                 else
1164                                         action = Action.LeaveOnStack;
1165
1166                                 warning_always_matches = true;
1167                         } else if (Convert.ExplicitReferenceConversionExists (etype, probe_type)){
1168                                 if (etype.IsGenericParameter)
1169                                         expr = new BoxedCast (expr, etype);
1170
1171                                 //
1172                                 // Second case: explicit reference convresion
1173                                 //
1174                                 if (expr is NullLiteral)
1175                                         action = Action.AlwaysFalse;
1176                                 else
1177                                         action = Action.Probe;
1178                         } else {
1179                                 action = Action.AlwaysFalse;
1180                                 warning_never_matches = true;
1181                         }
1182
1183                         if (warning_always_matches)
1184                                 Warning (183, "The given expression is always of the provided ('{0}') type", TypeManager.CSharpName (probe_type));
1185                         else if (warning_never_matches){
1186                                 if (!(probe_type.IsInterface || expr.Type.IsInterface))
1187                                         Warning (184, "The given expression is never of the provided ('{0}') type", TypeManager.CSharpName (probe_type));
1188                         }
1189
1190                         return this;
1191                 }
1192         }
1193
1194         /// <summary>
1195         ///   Implementation of the `as' operator.
1196         /// </summary>
1197         public class As : Probe {
1198                 public As (Expression expr, Expression probe_type, Location l)
1199                         : base (expr, probe_type, l)
1200                 {
1201                 }
1202
1203                 bool do_isinst = false;
1204
1205                 public override void Emit (EmitContext ec)
1206                 {
1207                         ILGenerator ig = ec.ig;
1208
1209                         expr.Emit (ec);
1210
1211                         if (do_isinst)
1212                                 ig.Emit (OpCodes.Isinst, probe_type);
1213                 }
1214
1215                 static void Error_CannotConvertType (Type source, Type target, Location loc)
1216                 {
1217                         Report.Error (
1218                                 39, loc, "as operator can not convert from `" +
1219                                 TypeManager.CSharpName (source) + "' to `" +
1220                                 TypeManager.CSharpName (target) + "'");
1221                 }
1222
1223                 public override Expression DoResolve (EmitContext ec)
1224                 {
1225                         Expression e = base.DoResolve (ec);
1226
1227                         if (e == null)
1228                                 return null;
1229
1230                         type = probe_type;
1231                         eclass = ExprClass.Value;
1232                         Type etype = expr.Type;
1233
1234                         if (TypeManager.IsValueType (probe_type)){
1235                                 Report.Error (77, loc, "The as operator should be used with a reference type only (" +
1236                                               TypeManager.CSharpName (probe_type) + " is a value type)");
1237                                 return null;
1238
1239                         }
1240
1241                         e = Convert.ImplicitConversion (ec, expr, probe_type, loc);
1242                         if (e != null){
1243                                 expr = e;
1244                                 do_isinst = false;
1245                                 return this;
1246                         }
1247
1248                         if (Convert.ExplicitReferenceConversionExists (etype, probe_type)){
1249                                 if (etype.IsGenericParameter)
1250                                         expr = new BoxedCast (expr, etype);
1251
1252                                 do_isinst = true;
1253                                 return this;
1254                         }
1255
1256                         Error_CannotConvertType (etype, probe_type, loc);
1257                         return null;
1258                 }
1259         }
1260
1261         /// <summary>
1262         ///   This represents a typecast in the source language.
1263         ///
1264         ///   FIXME: Cast expressions have an unusual set of parsing
1265         ///   rules, we need to figure those out.
1266         /// </summary>
1267         public class Cast : Expression {
1268                 Expression target_type;
1269                 Expression expr;
1270
1271                 public Cast (Expression cast_type, Expression expr, Location loc)
1272                 {
1273                         this.target_type = cast_type;
1274                         this.expr = expr;
1275                         this.loc = loc;
1276                 }
1277
1278                 public Expression TargetType {
1279                         get {
1280                                 return target_type;
1281                         }
1282                 }
1283
1284                 public Expression Expr {
1285                         get {
1286                                 return expr;
1287                         }
1288                         set {
1289                                 expr = value;
1290                         }
1291                 }
1292
1293                 bool CheckRange (EmitContext ec, long value, Type type, long min, long max)
1294                 {
1295                         if (!ec.ConstantCheckState)
1296                                 return true;
1297
1298                         if ((value < min) || (value > max)) {
1299                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1300                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1301                                        "syntax to override)");
1302                                 return false;
1303                         }
1304
1305                         return true;
1306                 }
1307
1308                 bool CheckRange (EmitContext ec, ulong value, Type type, ulong max)
1309                 {
1310                         if (!ec.ConstantCheckState)
1311                                 return true;
1312
1313                         if (value > max) {
1314                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1315                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1316                                        "syntax to override)");
1317                                 return false;
1318                         }
1319
1320                         return true;
1321                 }
1322
1323                 bool CheckUnsigned (EmitContext ec, long value, Type type)
1324                 {
1325                         if (!ec.ConstantCheckState)
1326                                 return true;
1327
1328                         if (value < 0) {
1329                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1330                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1331                                        "syntax to override)");
1332                                 return false;
1333                         }
1334
1335                         return true;
1336                 }
1337
1338                 /// <summary>
1339                 ///   Attempts to do a compile-time folding of a constant cast.
1340                 /// </summary>
1341                 Expression TryReduce (EmitContext ec, Type target_type)
1342                 {
1343                         Expression real_expr = expr;
1344                         if (real_expr is EnumConstant)
1345                                 real_expr = ((EnumConstant) real_expr).Child;
1346
1347                         if (real_expr is ByteConstant){
1348                                 byte v = ((ByteConstant) real_expr).Value;
1349
1350                                 if (target_type == TypeManager.sbyte_type) {
1351                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1352                                                 return null;
1353                                         return new SByteConstant ((sbyte) v);
1354                                 }
1355                                 if (target_type == TypeManager.short_type)
1356                                         return new ShortConstant ((short) v);
1357                                 if (target_type == TypeManager.ushort_type)
1358                                         return new UShortConstant ((ushort) v);
1359                                 if (target_type == TypeManager.int32_type)
1360                                         return new IntConstant ((int) v);
1361                                 if (target_type == TypeManager.uint32_type)
1362                                         return new UIntConstant ((uint) v);
1363                                 if (target_type == TypeManager.int64_type)
1364                                         return new LongConstant ((long) v);
1365                                 if (target_type == TypeManager.uint64_type)
1366                                         return new ULongConstant ((ulong) v);
1367                                 if (target_type == TypeManager.float_type)
1368                                         return new FloatConstant ((float) v);
1369                                 if (target_type == TypeManager.double_type)
1370                                         return new DoubleConstant ((double) v);
1371                                 if (target_type == TypeManager.char_type)
1372                                         return new CharConstant ((char) v);
1373                                 if (target_type == TypeManager.decimal_type)
1374                                         return new DecimalConstant ((decimal) v);
1375                         }
1376                         if (real_expr is SByteConstant){
1377                                 sbyte v = ((SByteConstant) real_expr).Value;
1378
1379                                 if (target_type == TypeManager.byte_type) {
1380                                         if (!CheckUnsigned (ec, v, target_type))
1381                                                 return null;
1382                                         return new ByteConstant ((byte) v);
1383                                 }
1384                                 if (target_type == TypeManager.short_type)
1385                                         return new ShortConstant ((short) v);
1386                                 if (target_type == TypeManager.ushort_type) {
1387                                         if (!CheckUnsigned (ec, v, target_type))
1388                                                 return null;
1389                                         return new UShortConstant ((ushort) v);
1390                                 } if (target_type == TypeManager.int32_type)
1391                                         return new IntConstant ((int) v);
1392                                 if (target_type == TypeManager.uint32_type) {
1393                                         if (!CheckUnsigned (ec, v, target_type))
1394                                                 return null;
1395                                         return new UIntConstant ((uint) v);
1396                                 } if (target_type == TypeManager.int64_type)
1397                                         return new LongConstant ((long) v);
1398                                 if (target_type == TypeManager.uint64_type) {
1399                                         if (!CheckUnsigned (ec, v, target_type))
1400                                                 return null;
1401                                         return new ULongConstant ((ulong) v);
1402                                 }
1403                                 if (target_type == TypeManager.float_type)
1404                                         return new FloatConstant ((float) v);
1405                                 if (target_type == TypeManager.double_type)
1406                                         return new DoubleConstant ((double) v);
1407                                 if (target_type == TypeManager.char_type) {
1408                                         if (!CheckUnsigned (ec, v, target_type))
1409                                                 return null;
1410                                         return new CharConstant ((char) v);
1411                                 }
1412                                 if (target_type == TypeManager.decimal_type)
1413                                         return new DecimalConstant ((decimal) v);
1414                         }
1415                         if (real_expr is ShortConstant){
1416                                 short v = ((ShortConstant) real_expr).Value;
1417
1418                                 if (target_type == TypeManager.byte_type) {
1419                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1420                                                 return null;
1421                                         return new ByteConstant ((byte) v);
1422                                 }
1423                                 if (target_type == TypeManager.sbyte_type) {
1424                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1425                                                 return null;
1426                                         return new SByteConstant ((sbyte) v);
1427                                 }
1428                                 if (target_type == TypeManager.ushort_type) {
1429                                         if (!CheckUnsigned (ec, v, target_type))
1430                                                 return null;
1431                                         return new UShortConstant ((ushort) v);
1432                                 }
1433                                 if (target_type == TypeManager.int32_type)
1434                                         return new IntConstant ((int) v);
1435                                 if (target_type == TypeManager.uint32_type) {
1436                                         if (!CheckUnsigned (ec, v, target_type))
1437                                                 return null;
1438                                         return new UIntConstant ((uint) v);
1439                                 }
1440                                 if (target_type == TypeManager.int64_type)
1441                                         return new LongConstant ((long) v);
1442                                 if (target_type == TypeManager.uint64_type) {
1443                                         if (!CheckUnsigned (ec, v, target_type))
1444                                                 return null;
1445                                         return new ULongConstant ((ulong) v);
1446                                 }
1447                                 if (target_type == TypeManager.float_type)
1448                                         return new FloatConstant ((float) v);
1449                                 if (target_type == TypeManager.double_type)
1450                                         return new DoubleConstant ((double) v);
1451                                 if (target_type == TypeManager.char_type) {
1452                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1453                                                 return null;
1454                                         return new CharConstant ((char) v);
1455                                 }
1456                                 if (target_type == TypeManager.decimal_type)
1457                                         return new DecimalConstant ((decimal) v);
1458                         }
1459                         if (real_expr is UShortConstant){
1460                                 ushort v = ((UShortConstant) real_expr).Value;
1461
1462                                 if (target_type == TypeManager.byte_type) {
1463                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1464                                                 return null;
1465                                         return new ByteConstant ((byte) v);
1466                                 }
1467                                 if (target_type == TypeManager.sbyte_type) {
1468                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1469                                                 return null;
1470                                         return new SByteConstant ((sbyte) v);
1471                                 }
1472                                 if (target_type == TypeManager.short_type) {
1473                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1474                                                 return null;
1475                                         return new ShortConstant ((short) v);
1476                                 }
1477                                 if (target_type == TypeManager.int32_type)
1478                                         return new IntConstant ((int) v);
1479                                 if (target_type == TypeManager.uint32_type)
1480                                         return new UIntConstant ((uint) v);
1481                                 if (target_type == TypeManager.int64_type)
1482                                         return new LongConstant ((long) v);
1483                                 if (target_type == TypeManager.uint64_type)
1484                                         return new ULongConstant ((ulong) v);
1485                                 if (target_type == TypeManager.float_type)
1486                                         return new FloatConstant ((float) v);
1487                                 if (target_type == TypeManager.double_type)
1488                                         return new DoubleConstant ((double) v);
1489                                 if (target_type == TypeManager.char_type) {
1490                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1491                                                 return null;
1492                                         return new CharConstant ((char) v);
1493                                 }
1494                                 if (target_type == TypeManager.decimal_type)
1495                                         return new DecimalConstant ((decimal) v);
1496                         }
1497                         if (real_expr is IntConstant){
1498                                 int v = ((IntConstant) real_expr).Value;
1499
1500                                 if (target_type == TypeManager.byte_type) {
1501                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1502                                                 return null;
1503                                         return new ByteConstant ((byte) v);
1504                                 }
1505                                 if (target_type == TypeManager.sbyte_type) {
1506                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1507                                                 return null;
1508                                         return new SByteConstant ((sbyte) v);
1509                                 }
1510                                 if (target_type == TypeManager.short_type) {
1511                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1512                                                 return null;
1513                                         return new ShortConstant ((short) v);
1514                                 }
1515                                 if (target_type == TypeManager.ushort_type) {
1516                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1517                                                 return null;
1518                                         return new UShortConstant ((ushort) v);
1519                                 }
1520                                 if (target_type == TypeManager.uint32_type) {
1521                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1522                                                 return null;
1523                                         return new UIntConstant ((uint) v);
1524                                 }
1525                                 if (target_type == TypeManager.int64_type)
1526                                         return new LongConstant ((long) v);
1527                                 if (target_type == TypeManager.uint64_type) {
1528                                         if (!CheckUnsigned (ec, v, target_type))
1529                                                 return null;
1530                                         return new ULongConstant ((ulong) v);
1531                                 }
1532                                 if (target_type == TypeManager.float_type)
1533                                         return new FloatConstant ((float) v);
1534                                 if (target_type == TypeManager.double_type)
1535                                         return new DoubleConstant ((double) v);
1536                                 if (target_type == TypeManager.char_type) {
1537                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1538                                                 return null;
1539                                         return new CharConstant ((char) v);
1540                                 }
1541                                 if (target_type == TypeManager.decimal_type)
1542                                         return new DecimalConstant ((decimal) v);
1543                         }
1544                         if (real_expr is UIntConstant){
1545                                 uint v = ((UIntConstant) real_expr).Value;
1546
1547                                 if (target_type == TypeManager.byte_type) {
1548                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1549                                                 return null;
1550                                         return new ByteConstant ((byte) v);
1551                                 }
1552                                 if (target_type == TypeManager.sbyte_type) {
1553                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1554                                                 return null;
1555                                         return new SByteConstant ((sbyte) v);
1556                                 }
1557                                 if (target_type == TypeManager.short_type) {
1558                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1559                                                 return null;
1560                                         return new ShortConstant ((short) v);
1561                                 }
1562                                 if (target_type == TypeManager.ushort_type) {
1563                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1564                                                 return null;
1565                                         return new UShortConstant ((ushort) v);
1566                                 }
1567                                 if (target_type == TypeManager.int32_type) {
1568                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1569                                                 return null;
1570                                         return new IntConstant ((int) v);
1571                                 }
1572                                 if (target_type == TypeManager.int64_type)
1573                                         return new LongConstant ((long) v);
1574                                 if (target_type == TypeManager.uint64_type)
1575                                         return new ULongConstant ((ulong) v);
1576                                 if (target_type == TypeManager.float_type)
1577                                         return new FloatConstant ((float) v);
1578                                 if (target_type == TypeManager.double_type)
1579                                         return new DoubleConstant ((double) v);
1580                                 if (target_type == TypeManager.char_type) {
1581                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1582                                                 return null;
1583                                         return new CharConstant ((char) v);
1584                                 }
1585                                 if (target_type == TypeManager.decimal_type)
1586                                         return new DecimalConstant ((decimal) v);
1587                         }
1588                         if (real_expr is LongConstant){
1589                                 long v = ((LongConstant) real_expr).Value;
1590
1591                                 if (target_type == TypeManager.byte_type) {
1592                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1593                                                 return null;
1594                                         return new ByteConstant ((byte) v);
1595                                 }
1596                                 if (target_type == TypeManager.sbyte_type) {
1597                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1598                                                 return null;
1599                                         return new SByteConstant ((sbyte) v);
1600                                 }
1601                                 if (target_type == TypeManager.short_type) {
1602                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1603                                                 return null;
1604                                         return new ShortConstant ((short) v);
1605                                 }
1606                                 if (target_type == TypeManager.ushort_type) {
1607                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1608                                                 return null;
1609                                         return new UShortConstant ((ushort) v);
1610                                 }
1611                                 if (target_type == TypeManager.int32_type) {
1612                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1613                                                 return null;
1614                                         return new IntConstant ((int) v);
1615                                 }
1616                                 if (target_type == TypeManager.uint32_type) {
1617                                         if (!CheckRange (ec, v, target_type, UInt32.MinValue, UInt32.MaxValue))
1618                                                 return null;
1619                                         return new UIntConstant ((uint) v);
1620                                 }
1621                                 if (target_type == TypeManager.uint64_type) {
1622                                         if (!CheckUnsigned (ec, v, target_type))
1623                                                 return null;
1624                                         return new ULongConstant ((ulong) v);
1625                                 }
1626                                 if (target_type == TypeManager.float_type)
1627                                         return new FloatConstant ((float) v);
1628                                 if (target_type == TypeManager.double_type)
1629                                         return new DoubleConstant ((double) v);
1630                                 if (target_type == TypeManager.char_type) {
1631                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1632                                                 return null;
1633                                         return new CharConstant ((char) v);
1634                                 }
1635                                 if (target_type == TypeManager.decimal_type)
1636                                         return new DecimalConstant ((decimal) v);
1637                         }
1638                         if (real_expr is ULongConstant){
1639                                 ulong v = ((ULongConstant) real_expr).Value;
1640
1641                                 if (target_type == TypeManager.byte_type) {
1642                                         if (!CheckRange (ec, v, target_type, Byte.MaxValue))
1643                                                 return null;
1644                                         return new ByteConstant ((byte) v);
1645                                 }
1646                                 if (target_type == TypeManager.sbyte_type) {
1647                                         if (!CheckRange (ec, v, target_type, (ulong) SByte.MaxValue))
1648                                                 return null;
1649                                         return new SByteConstant ((sbyte) v);
1650                                 }
1651                                 if (target_type == TypeManager.short_type) {
1652                                         if (!CheckRange (ec, v, target_type, (ulong) Int16.MaxValue))
1653                                                 return null;
1654                                         return new ShortConstant ((short) v);
1655                                 }
1656                                 if (target_type == TypeManager.ushort_type) {
1657                                         if (!CheckRange (ec, v, target_type, UInt16.MaxValue))
1658                                                 return null;
1659                                         return new UShortConstant ((ushort) v);
1660                                 }
1661                                 if (target_type == TypeManager.int32_type) {
1662                                         if (!CheckRange (ec, v, target_type, Int32.MaxValue))
1663                                                 return null;
1664                                         return new IntConstant ((int) v);
1665                                 }
1666                                 if (target_type == TypeManager.uint32_type) {
1667                                         if (!CheckRange (ec, v, target_type, UInt32.MaxValue))
1668                                                 return null;
1669                                         return new UIntConstant ((uint) v);
1670                                 }
1671                                 if (target_type == TypeManager.int64_type) {
1672                                         if (!CheckRange (ec, v, target_type, (ulong) Int64.MaxValue))
1673                                                 return null;
1674                                         return new LongConstant ((long) v);
1675                                 }
1676                                 if (target_type == TypeManager.float_type)
1677                                         return new FloatConstant ((float) v);
1678                                 if (target_type == TypeManager.double_type)
1679                                         return new DoubleConstant ((double) v);
1680                                 if (target_type == TypeManager.char_type) {
1681                                         if (!CheckRange (ec, v, target_type, Char.MaxValue))
1682                                                 return null;
1683                                         return new CharConstant ((char) v);
1684                                 }
1685                                 if (target_type == TypeManager.decimal_type)
1686                                         return new DecimalConstant ((decimal) v);
1687                         }
1688                         if (real_expr is FloatConstant){
1689                                 float v = ((FloatConstant) real_expr).Value;
1690
1691                                 if (target_type == TypeManager.byte_type)
1692                                         return new ByteConstant ((byte) v);
1693                                 if (target_type == TypeManager.sbyte_type)
1694                                         return new SByteConstant ((sbyte) v);
1695                                 if (target_type == TypeManager.short_type)
1696                                         return new ShortConstant ((short) v);
1697                                 if (target_type == TypeManager.ushort_type)
1698                                         return new UShortConstant ((ushort) v);
1699                                 if (target_type == TypeManager.int32_type)
1700                                         return new IntConstant ((int) v);
1701                                 if (target_type == TypeManager.uint32_type)
1702                                         return new UIntConstant ((uint) v);
1703                                 if (target_type == TypeManager.int64_type)
1704                                         return new LongConstant ((long) v);
1705                                 if (target_type == TypeManager.uint64_type)
1706                                         return new ULongConstant ((ulong) v);
1707                                 if (target_type == TypeManager.double_type)
1708                                         return new DoubleConstant ((double) v);
1709                                 if (target_type == TypeManager.char_type)
1710                                         return new CharConstant ((char) v);
1711                                 if (target_type == TypeManager.decimal_type)
1712                                         return new DecimalConstant ((decimal) v);
1713                         }
1714                         if (real_expr is DoubleConstant){
1715                                 double v = ((DoubleConstant) real_expr).Value;
1716
1717                                 if (target_type == TypeManager.byte_type){
1718                                         return new ByteConstant ((byte) v);
1719                                 } if (target_type == TypeManager.sbyte_type)
1720                                         return new SByteConstant ((sbyte) v);
1721                                 if (target_type == TypeManager.short_type)
1722                                         return new ShortConstant ((short) v);
1723                                 if (target_type == TypeManager.ushort_type)
1724                                         return new UShortConstant ((ushort) v);
1725                                 if (target_type == TypeManager.int32_type)
1726                                         return new IntConstant ((int) v);
1727                                 if (target_type == TypeManager.uint32_type)
1728                                         return new UIntConstant ((uint) v);
1729                                 if (target_type == TypeManager.int64_type)
1730                                         return new LongConstant ((long) v);
1731                                 if (target_type == TypeManager.uint64_type)
1732                                         return new ULongConstant ((ulong) v);
1733                                 if (target_type == TypeManager.float_type)
1734                                         return new FloatConstant ((float) v);
1735                                 if (target_type == TypeManager.char_type)
1736                                         return new CharConstant ((char) v);
1737                                 if (target_type == TypeManager.decimal_type)
1738                                         return new DecimalConstant ((decimal) v);
1739                         }
1740
1741                         if (real_expr is CharConstant){
1742                                 char v = ((CharConstant) real_expr).Value;
1743
1744                                 if (target_type == TypeManager.byte_type) {
1745                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1746                                                 return null;
1747                                         return new ByteConstant ((byte) v);
1748                                 }
1749                                 if (target_type == TypeManager.sbyte_type) {
1750                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1751                                                 return null;
1752                                         return new SByteConstant ((sbyte) v);
1753                                 }
1754                                 if (target_type == TypeManager.short_type) {
1755                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1756                                                 return null;
1757                                         return new ShortConstant ((short) v);
1758                                 }
1759                                 if (target_type == TypeManager.int32_type)
1760                                         return new IntConstant ((int) v);
1761                                 if (target_type == TypeManager.uint32_type)
1762                                         return new UIntConstant ((uint) v);
1763                                 if (target_type == TypeManager.int64_type)
1764                                         return new LongConstant ((long) v);
1765                                 if (target_type == TypeManager.uint64_type)
1766                                         return new ULongConstant ((ulong) v);
1767                                 if (target_type == TypeManager.float_type)
1768                                         return new FloatConstant ((float) v);
1769                                 if (target_type == TypeManager.double_type)
1770                                         return new DoubleConstant ((double) v);
1771                                 if (target_type == TypeManager.char_type) {
1772                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1773                                                 return null;
1774                                         return new CharConstant ((char) v);
1775                                 }
1776                                 if (target_type == TypeManager.decimal_type)
1777                                         return new DecimalConstant ((decimal) v);
1778                         }
1779
1780                         return null;
1781                 }
1782
1783                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
1784                 {
1785                         expr = expr.DoResolveLValue (ec, right_side);
1786                         if (expr == null)
1787                                 return null;
1788
1789                         return ResolveRest (ec);
1790                 }
1791
1792                 public override Expression DoResolve (EmitContext ec)
1793                 {
1794                         expr = expr.Resolve (ec);
1795                         if (expr == null)
1796                                 return null;
1797
1798                         return ResolveRest (ec);
1799                 }
1800
1801                 Expression ResolveRest (EmitContext ec)
1802                 {
1803                         TypeExpr target = target_type.ResolveAsTypeTerminal (ec);
1804                         if (target == null)
1805                                 return null;
1806
1807                         type = target.Type;
1808
1809                         CheckObsoleteAttribute (type);
1810
1811                         if (type.IsAbstract && type.IsSealed) {
1812                                 Report.Error (716, loc, "Cannot convert to static type '{0}'", TypeManager.CSharpName (type));
1813                                 return null;
1814                         }
1815
1816                         eclass = ExprClass.Value;
1817
1818                         if (expr is Constant){
1819                                 Expression e = TryReduce (ec, type);
1820
1821                                 if (e != null)
1822                                         return e;
1823                         }
1824
1825                         if (type.IsPointer && !ec.InUnsafe) {
1826                                 UnsafeError (loc);
1827                                 return null;
1828                         }
1829                         expr = Convert.ExplicitConversion (ec, expr, type, loc);
1830                         return expr;
1831                 }
1832
1833                 public override void Emit (EmitContext ec)
1834                 {
1835                         //
1836                         // This one will never happen
1837                         //
1838                         throw new Exception ("Should not happen");
1839                 }
1840         }
1841
1842         /// <summary>
1843         ///   Binary operators
1844         /// </summary>
1845         public class Binary : Expression {
1846                 public enum Operator : byte {
1847                         Multiply, Division, Modulus,
1848                         Addition, Subtraction,
1849                         LeftShift, RightShift,
1850                         LessThan, GreaterThan, LessThanOrEqual, GreaterThanOrEqual,
1851                         Equality, Inequality,
1852                         BitwiseAnd,
1853                         ExclusiveOr,
1854                         BitwiseOr,
1855                         LogicalAnd,
1856                         LogicalOr,
1857                         TOP
1858                 }
1859
1860                 Operator oper;
1861                 Expression left, right;
1862
1863                 // This must be kept in sync with Operator!!!
1864                 public static readonly string [] oper_names;
1865
1866                 static Binary ()
1867                 {
1868                         oper_names = new string [(int) Operator.TOP];
1869
1870                         oper_names [(int) Operator.Multiply] = "op_Multiply";
1871                         oper_names [(int) Operator.Division] = "op_Division";
1872                         oper_names [(int) Operator.Modulus] = "op_Modulus";
1873                         oper_names [(int) Operator.Addition] = "op_Addition";
1874                         oper_names [(int) Operator.Subtraction] = "op_Subtraction";
1875                         oper_names [(int) Operator.LeftShift] = "op_LeftShift";
1876                         oper_names [(int) Operator.RightShift] = "op_RightShift";
1877                         oper_names [(int) Operator.LessThan] = "op_LessThan";
1878                         oper_names [(int) Operator.GreaterThan] = "op_GreaterThan";
1879                         oper_names [(int) Operator.LessThanOrEqual] = "op_LessThanOrEqual";
1880                         oper_names [(int) Operator.GreaterThanOrEqual] = "op_GreaterThanOrEqual";
1881                         oper_names [(int) Operator.Equality] = "op_Equality";
1882                         oper_names [(int) Operator.Inequality] = "op_Inequality";
1883                         oper_names [(int) Operator.BitwiseAnd] = "op_BitwiseAnd";
1884                         oper_names [(int) Operator.BitwiseOr] = "op_BitwiseOr";
1885                         oper_names [(int) Operator.ExclusiveOr] = "op_ExclusiveOr";
1886                         oper_names [(int) Operator.LogicalOr] = "op_LogicalOr";
1887                         oper_names [(int) Operator.LogicalAnd] = "op_LogicalAnd";
1888                 }
1889
1890                 public Binary (Operator oper, Expression left, Expression right, Location loc)
1891                 {
1892                         this.oper = oper;
1893                         this.left = left;
1894                         this.right = right;
1895                         this.loc = loc;
1896                 }
1897
1898                 public Operator Oper {
1899                         get {
1900                                 return oper;
1901                         }
1902                         set {
1903                                 oper = value;
1904                         }
1905                 }
1906
1907                 public Expression Left {
1908                         get {
1909                                 return left;
1910                         }
1911                         set {
1912                                 left = value;
1913                         }
1914                 }
1915
1916                 public Expression Right {
1917                         get {
1918                                 return right;
1919                         }
1920                         set {
1921                                 right = value;
1922                         }
1923                 }
1924
1925
1926                 /// <summary>
1927                 ///   Returns a stringified representation of the Operator
1928                 /// </summary>
1929                 static string OperName (Operator oper)
1930                 {
1931                         switch (oper){
1932                         case Operator.Multiply:
1933                                 return "*";
1934                         case Operator.Division:
1935                                 return "/";
1936                         case Operator.Modulus:
1937                                 return "%";
1938                         case Operator.Addition:
1939                                 return "+";
1940                         case Operator.Subtraction:
1941                                 return "-";
1942                         case Operator.LeftShift:
1943                                 return "<<";
1944                         case Operator.RightShift:
1945                                 return ">>";
1946                         case Operator.LessThan:
1947                                 return "<";
1948                         case Operator.GreaterThan:
1949                                 return ">";
1950                         case Operator.LessThanOrEqual:
1951                                 return "<=";
1952                         case Operator.GreaterThanOrEqual:
1953                                 return ">=";
1954                         case Operator.Equality:
1955                                 return "==";
1956                         case Operator.Inequality:
1957                                 return "!=";
1958                         case Operator.BitwiseAnd:
1959                                 return "&";
1960                         case Operator.BitwiseOr:
1961                                 return "|";
1962                         case Operator.ExclusiveOr:
1963                                 return "^";
1964                         case Operator.LogicalOr:
1965                                 return "||";
1966                         case Operator.LogicalAnd:
1967                                 return "&&";
1968                         }
1969
1970                         return oper.ToString ();
1971                 }
1972
1973                 public override string ToString ()
1974                 {
1975                         return "operator " + OperName (oper) + "(" + left.ToString () + ", " +
1976                                 right.ToString () + ")";
1977                 }
1978
1979                 Expression ForceConversion (EmitContext ec, Expression expr, Type target_type)
1980                 {
1981                         if (expr.Type == target_type)
1982                                 return expr;
1983
1984                         return Convert.ImplicitConversion (ec, expr, target_type, loc);
1985                 }
1986
1987                 public static void Error_OperatorAmbiguous (Location loc, Operator oper, Type l, Type r)
1988                 {
1989                         Report.Error (
1990                                 34, loc, "Operator `" + OperName (oper)
1991                                 + "' is ambiguous on operands of type `"
1992                                 + TypeManager.CSharpName (l) + "' "
1993                                 + "and `" + TypeManager.CSharpName (r)
1994                                 + "'");
1995                 }
1996
1997                 bool IsOfType (EmitContext ec, Type l, Type r, Type t, bool check_user_conversions)
1998                 {
1999                         if ((l == t) || (r == t))
2000                                 return true;
2001
2002                         if (!check_user_conversions)
2003                                 return false;
2004
2005                         if (Convert.ImplicitUserConversionExists (ec, l, t))
2006                                 return true;
2007                         else if (Convert.ImplicitUserConversionExists (ec, r, t))
2008                                 return true;
2009                         else
2010                                 return false;
2011                 }
2012
2013                 //
2014                 // Note that handling the case l == Decimal || r == Decimal
2015                 // is taken care of by the Step 1 Operator Overload resolution.
2016                 //
2017                 // If `check_user_conv' is true, we also check whether a user-defined conversion
2018                 // exists.  Note that we only need to do this if both arguments are of a user-defined
2019                 // type, otherwise ConvertImplict() already finds the user-defined conversion for us,
2020                 // so we don't explicitly check for performance reasons.
2021                 //
2022                 bool DoNumericPromotions (EmitContext ec, Type l, Type r, bool check_user_conv)
2023                 {
2024                         if (IsOfType (ec, l, r, TypeManager.double_type, check_user_conv)){
2025                                 //
2026                                 // If either operand is of type double, the other operand is
2027                                 // conveted to type double.
2028                                 //
2029                                 if (r != TypeManager.double_type)
2030                                         right = Convert.ImplicitConversion (ec, right, TypeManager.double_type, loc);
2031                                 if (l != TypeManager.double_type)
2032                                         left = Convert.ImplicitConversion (ec, left, TypeManager.double_type, loc);
2033
2034                                 type = TypeManager.double_type;
2035                         } else if (IsOfType (ec, l, r, TypeManager.float_type, check_user_conv)){
2036                                 //
2037                                 // if either operand is of type float, the other operand is
2038                                 // converted to type float.
2039                                 //
2040                                 if (r != TypeManager.double_type)
2041                                         right = Convert.ImplicitConversion (ec, right, TypeManager.float_type, loc);
2042                                 if (l != TypeManager.double_type)
2043                                         left = Convert.ImplicitConversion (ec, left, TypeManager.float_type, loc);
2044                                 type = TypeManager.float_type;
2045                         } else if (IsOfType (ec, l, r, TypeManager.uint64_type, check_user_conv)){
2046                                 Expression e;
2047                                 Type other;
2048                                 //
2049                                 // If either operand is of type ulong, the other operand is
2050                                 // converted to type ulong.  or an error ocurrs if the other
2051                                 // operand is of type sbyte, short, int or long
2052                                 //
2053                                 if (l == TypeManager.uint64_type){
2054                                         if (r != TypeManager.uint64_type){
2055                                                 if (right is IntConstant){
2056                                                         IntConstant ic = (IntConstant) right;
2057
2058                                                         e = Convert.TryImplicitIntConversion (l, ic);
2059                                                         if (e != null)
2060                                                                 right = e;
2061                                                 } else if (right is LongConstant){
2062                                                         long ll = ((LongConstant) right).Value;
2063
2064                                                         if (ll >= 0)
2065                                                                 right = new ULongConstant ((ulong) ll);
2066                                                 } else {
2067                                                         e = Convert.ImplicitNumericConversion (ec, right, l, loc);
2068                                                         if (e != null)
2069                                                                 right = e;
2070                                                 }
2071                                         }
2072                                         other = right.Type;
2073                                 } else {
2074                                         if (left is IntConstant){
2075                                                 e = Convert.TryImplicitIntConversion (r, (IntConstant) left);
2076                                                 if (e != null)
2077                                                         left = e;
2078                                         } else if (left is LongConstant){
2079                                                 long ll = ((LongConstant) left).Value;
2080
2081                                                 if (ll > 0)
2082                                                         left = new ULongConstant ((ulong) ll);
2083                                         } else {
2084                                                 e = Convert.ImplicitNumericConversion (ec, left, r, loc);
2085                                                 if (e != null)
2086                                                         left = e;
2087                                         }
2088                                         other = left.Type;
2089                                 }
2090
2091                                 if ((other == TypeManager.sbyte_type) ||
2092                                     (other == TypeManager.short_type) ||
2093                                     (other == TypeManager.int32_type) ||
2094                                     (other == TypeManager.int64_type))
2095                                         Error_OperatorAmbiguous (loc, oper, l, r);
2096                                 else {
2097                                         left = ForceConversion (ec, left, TypeManager.uint64_type);
2098                                         right = ForceConversion (ec, right, TypeManager.uint64_type);
2099                                 }
2100                                 type = TypeManager.uint64_type;
2101                         } else if (IsOfType (ec, l, r, TypeManager.int64_type, check_user_conv)){
2102                                 //
2103                                 // If either operand is of type long, the other operand is converted
2104                                 // to type long.
2105                                 //
2106                                 if (l != TypeManager.int64_type)
2107                                         left = Convert.ImplicitConversion (ec, left, TypeManager.int64_type, loc);
2108                                 if (r != TypeManager.int64_type)
2109                                         right = Convert.ImplicitConversion (ec, right, TypeManager.int64_type, loc);
2110
2111                                 type = TypeManager.int64_type;
2112                         } else if (IsOfType (ec, l, r, TypeManager.uint32_type, check_user_conv)){
2113                                 //
2114                                 // If either operand is of type uint, and the other
2115                                 // operand is of type sbyte, short or int, othe operands are
2116                                 // converted to type long (unless we have an int constant).
2117                                 //
2118                                 Type other = null;
2119
2120                                 if (l == TypeManager.uint32_type){
2121                                         if (right is IntConstant){
2122                                                 IntConstant ic = (IntConstant) right;
2123                                                 int val = ic.Value;
2124
2125                                                 if (val >= 0){
2126                                                         right = new UIntConstant ((uint) val);
2127                                                         type = l;
2128
2129                                                         return true;
2130                                                 }
2131                                         }
2132                                         other = r;
2133                                 } else if (r == TypeManager.uint32_type){
2134                                         if (left is IntConstant){
2135                                                 IntConstant ic = (IntConstant) left;
2136                                                 int val = ic.Value;
2137
2138                                                 if (val >= 0){
2139                                                         left = new UIntConstant ((uint) val);
2140                                                         type = r;
2141                                                         return true;
2142                                                 }
2143                                         }
2144
2145                                         other = l;
2146                                 }
2147
2148                                 if ((other == TypeManager.sbyte_type) ||
2149                                     (other == TypeManager.short_type) ||
2150                                     (other == TypeManager.int32_type)){
2151                                         left = ForceConversion (ec, left, TypeManager.int64_type);
2152                                         right = ForceConversion (ec, right, TypeManager.int64_type);
2153                                         type = TypeManager.int64_type;
2154                                 } else {
2155                                         //
2156                                         // if either operand is of type uint, the other
2157                                         // operand is converd to type uint
2158                                         //
2159                                         left = ForceConversion (ec, left, TypeManager.uint32_type);
2160                                         right = ForceConversion (ec, right, TypeManager.uint32_type);
2161                                         type = TypeManager.uint32_type;
2162                                 }
2163                         } else if (l == TypeManager.decimal_type || r == TypeManager.decimal_type){
2164                                 if (l != TypeManager.decimal_type)
2165                                         left = Convert.ImplicitConversion (ec, left, TypeManager.decimal_type, loc);
2166
2167                                 if (r != TypeManager.decimal_type)
2168                                         right = Convert.ImplicitConversion (ec, right, TypeManager.decimal_type, loc);
2169                                 type = TypeManager.decimal_type;
2170                         } else {
2171                                 left = ForceConversion (ec, left, TypeManager.int32_type);
2172                                 right = ForceConversion (ec, right, TypeManager.int32_type);
2173
2174                                 type = TypeManager.int32_type;
2175                         }
2176
2177                         return (left != null) && (right != null);
2178                 }
2179
2180                 static public void Error_OperatorCannotBeApplied (Location loc, string name, Type l, Type r)
2181                 {
2182                         Report.Error (19, loc,
2183                                "Operator " + name + " cannot be applied to operands of type `" +
2184                                TypeManager.CSharpName (l) + "' and `" +
2185                                TypeManager.CSharpName (r) + "'");
2186                 }
2187
2188                 void Error_OperatorCannotBeApplied ()
2189                 {
2190                         Error_OperatorCannotBeApplied (loc, OperName (oper), left.Type, right.Type);
2191                 }
2192
2193                 static bool is_unsigned (Type t)
2194                 {
2195                         return (t == TypeManager.uint32_type || t == TypeManager.uint64_type ||
2196                                 t == TypeManager.short_type || t == TypeManager.byte_type);
2197                 }
2198
2199                 static bool is_user_defined (Type t)
2200                 {
2201                         if (t.IsSubclassOf (TypeManager.value_type) &&
2202                             (!TypeManager.IsBuiltinType (t) || t == TypeManager.decimal_type))
2203                                 return true;
2204                         else
2205                                 return false;
2206                 }
2207
2208                 Expression Make32or64 (EmitContext ec, Expression e)
2209                 {
2210                         Type t= e.Type;
2211
2212                         if (t == TypeManager.int32_type || t == TypeManager.uint32_type ||
2213                             t == TypeManager.int64_type || t == TypeManager.uint64_type)
2214                                 return e;
2215                         Expression ee = Convert.ImplicitConversion (ec, e, TypeManager.int32_type, loc);
2216                         if (ee != null)
2217                                 return ee;
2218                         ee = Convert.ImplicitConversion (ec, e, TypeManager.uint32_type, loc);
2219                         if (ee != null)
2220                                 return ee;
2221                         ee = Convert.ImplicitConversion (ec, e, TypeManager.int64_type, loc);
2222                         if (ee != null)
2223                                 return ee;
2224                         ee = Convert.ImplicitConversion (ec, e, TypeManager.uint64_type, loc);
2225                         if (ee != null)
2226                                 return ee;
2227                         return null;
2228                 }
2229
2230                 Expression CheckShiftArguments (EmitContext ec)
2231                 {
2232                         Expression e;
2233
2234                         e = ForceConversion (ec, right, TypeManager.int32_type);
2235                         if (e == null){
2236                                 Error_OperatorCannotBeApplied ();
2237                                 return null;
2238                         }
2239                         right = e;
2240
2241                         if (((e = Convert.ImplicitConversion (ec, left, TypeManager.int32_type, loc)) != null) ||
2242                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.uint32_type, loc)) != null) ||
2243                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.int64_type, loc)) != null) ||
2244                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.uint64_type, loc)) != null)){
2245                                 left = e;
2246                                 type = e.Type;
2247
2248                                 if (type == TypeManager.int32_type || type == TypeManager.uint32_type){
2249                                         right = new Binary (Binary.Operator.BitwiseAnd, right, new IntLiteral (31), loc);
2250                                         right = right.DoResolve (ec);
2251                                 } else {
2252                                         right = new Binary (Binary.Operator.BitwiseAnd, right, new IntLiteral (63), loc);
2253                                         right = right.DoResolve (ec);
2254                                 }
2255
2256                                 return this;
2257                         }
2258                         Error_OperatorCannotBeApplied ();
2259                         return null;
2260                 }
2261
2262                 Expression ResolveOperator (EmitContext ec)
2263                 {
2264                         Type l = left.Type;
2265                         Type r = right.Type;
2266
2267                         //
2268                         // Special cases: string or type parameter comapred to null
2269                         //
2270                         if (oper == Operator.Equality || oper == Operator.Inequality){
2271                                 if ((!TypeManager.IsValueType (l) && r == TypeManager.null_type) ||
2272                                     (!TypeManager.IsValueType (r) && l == TypeManager.null_type)) {
2273                                         Type = TypeManager.bool_type;
2274
2275                                         return this;
2276                                 }
2277
2278                                 if (l.IsGenericParameter && (right is NullLiteral)) {
2279                                         if (l.BaseType == TypeManager.value_type) {
2280                                                 Error_OperatorCannotBeApplied ();
2281                                                 return null;
2282                                         }
2283
2284                                         left = new BoxedCast (left);
2285                                         Type = TypeManager.bool_type;
2286                                         return this;
2287                                 }
2288
2289                                 if (r.IsGenericParameter && (left is NullLiteral)) {
2290                                         if (r.BaseType == TypeManager.value_type) {
2291                                                 Error_OperatorCannotBeApplied ();
2292                                                 return null;
2293                                         }
2294
2295                                         right = new BoxedCast (right);
2296                                         Type = TypeManager.bool_type;
2297                                         return this;
2298                                 }
2299
2300                                 // IntPtr equality
2301                                 if (l == TypeManager.intptr_type && r == TypeManager.intptr_type) {
2302                                         Type = TypeManager.bool_type;
2303
2304                                         return this;
2305                                 }
2306                         }
2307
2308                         //
2309                         // Do not perform operator overload resolution when both sides are
2310                         // built-in types
2311                         //
2312                         if (!(TypeManager.IsPrimitiveType (l) && TypeManager.IsPrimitiveType (r))){
2313                                 //
2314                                 // Step 1: Perform Operator Overload location
2315                                 //
2316                                 Expression left_expr, right_expr;
2317
2318                                 string op = oper_names [(int) oper];
2319
2320                                 MethodGroupExpr union;
2321                                 left_expr = MemberLookup (ec, l, op, MemberTypes.Method, AllBindingFlags, loc);
2322                                 if (r != l){
2323                                         right_expr = MemberLookup (
2324                                                 ec, r, op, MemberTypes.Method, AllBindingFlags, loc);
2325                                         union = Invocation.MakeUnionSet (left_expr, right_expr, loc);
2326                                 } else
2327                                         union = (MethodGroupExpr) left_expr;
2328
2329                                 if (union != null) {
2330                                         ArrayList args = new ArrayList (2);
2331                                         args.Add (new Argument (left, Argument.AType.Expression));
2332                                         args.Add (new Argument (right, Argument.AType.Expression));
2333
2334                                         MethodBase method = Invocation.OverloadResolve (
2335                                                 ec, union, args, true, Location.Null);
2336
2337                                         if (method != null) {
2338                                                 MethodInfo mi = (MethodInfo) method;
2339
2340                                                 return new BinaryMethod (mi.ReturnType, method, args);
2341                                         }
2342                                 }
2343                         }
2344
2345                         //
2346                         // Step 0: String concatenation (because overloading will get this wrong)
2347                         //
2348                         if (oper == Operator.Addition){
2349                                 //
2350                                 // If any of the arguments is a string, cast to string
2351                                 //
2352
2353                                 // Simple constant folding
2354                                 if (left is StringConstant && right is StringConstant)
2355                                         return new StringConstant (((StringConstant) left).Value + ((StringConstant) right).Value);
2356
2357                                 if (l == TypeManager.string_type || r == TypeManager.string_type) {
2358
2359                                         if (r == TypeManager.void_type || l == TypeManager.void_type) {
2360                                                 Error_OperatorCannotBeApplied ();
2361                                                 return null;
2362                                         }
2363
2364                                         // try to fold it in on the left
2365                                         if (left is StringConcat) {
2366
2367                                                 //
2368                                                 // We have to test here for not-null, since we can be doubly-resolved
2369                                                 // take care of not appending twice
2370                                                 //
2371                                                 if (type == null){
2372                                                         type = TypeManager.string_type;
2373                                                         ((StringConcat) left).Append (ec, right);
2374                                                         return left.Resolve (ec);
2375                                                 } else {
2376                                                         return left;
2377                                                 }
2378                                         }
2379
2380                                         // Otherwise, start a new concat expression
2381                                         return new StringConcat (ec, loc, left, right).Resolve (ec);
2382                                 }
2383
2384                                 //
2385                                 // Transform a + ( - b) into a - b
2386                                 //
2387                                 if (right is Unary){
2388                                         Unary right_unary = (Unary) right;
2389
2390                                         if (right_unary.Oper == Unary.Operator.UnaryNegation){
2391                                                 oper = Operator.Subtraction;
2392                                                 right = right_unary.Expr;
2393                                                 r = right.Type;
2394                                         }
2395                                 }
2396                         }
2397
2398                         if (oper == Operator.Equality || oper == Operator.Inequality){
2399                                 if (l == TypeManager.bool_type || r == TypeManager.bool_type){
2400                                         if (r != TypeManager.bool_type || l != TypeManager.bool_type){
2401                                                 Error_OperatorCannotBeApplied ();
2402                                                 return null;
2403                                         }
2404
2405                                         type = TypeManager.bool_type;
2406                                         return this;
2407                                 }
2408
2409                                 bool left_is_null = left is NullLiteral;
2410                                 bool right_is_null = right is NullLiteral;
2411                                 if (left_is_null || right_is_null) {
2412                                         if (oper == Operator.Equality)
2413                                                 return new BoolLiteral (left_is_null == right_is_null);
2414                                         else
2415                                                 return new BoolLiteral (left_is_null != right_is_null);
2416                                 }
2417
2418                                 //
2419                                 // operator != (object a, object b)
2420                                 // operator == (object a, object b)
2421                                 //
2422                                 // For this to be used, both arguments have to be reference-types.
2423                                 // Read the rationale on the spec (14.9.6)
2424                                 //
2425                                 // Also, if at compile time we know that the classes do not inherit
2426                                 // one from the other, then we catch the error there.
2427                                 //
2428                                 if (!(l.IsValueType || r.IsValueType)){
2429                                         type = TypeManager.bool_type;
2430
2431                                         if (l == r)
2432                                                 return this;
2433
2434                                         if (l.IsSubclassOf (r) || r.IsSubclassOf (l))
2435                                                 return this;
2436
2437                                         //
2438                                         // Also, a standard conversion must exist from either one
2439                                         //
2440                                         if (!(Convert.ImplicitStandardConversionExists (ec, left, r) ||
2441                                               Convert.ImplicitStandardConversionExists (ec, right, l))){
2442                                                 Error_OperatorCannotBeApplied ();
2443                                                 return null;
2444                                         }
2445                                         //
2446                                         // We are going to have to convert to an object to compare
2447                                         //
2448                                         if (l != TypeManager.object_type)
2449                                                 left = new EmptyCast (left, TypeManager.object_type);
2450                                         if (r != TypeManager.object_type)
2451                                                 right = new EmptyCast (right, TypeManager.object_type);
2452
2453                                         //
2454                                         // FIXME: CSC here catches errors cs254 and cs252
2455                                         //
2456                                         return this;
2457                                 }
2458
2459                                 //
2460                                 // One of them is a valuetype, but the other one is not.
2461                                 //
2462                                 if (!l.IsValueType || !r.IsValueType) {
2463                                         Error_OperatorCannotBeApplied ();
2464                                         return null;
2465                                 }
2466                         }
2467
2468                         // Only perform numeric promotions on:
2469                         // +, -, *, /, %, &, |, ^, ==, !=, <, >, <=, >=
2470                         //
2471                         if (oper == Operator.Addition || oper == Operator.Subtraction) {
2472                                 if (TypeManager.IsDelegateType (l)){
2473                                         if (((right.eclass == ExprClass.MethodGroup) ||
2474                                              (r == TypeManager.anonymous_method_type))){
2475                                                 if ((RootContext.Version != LanguageVersion.ISO_1)){
2476                                                         Expression tmp = Convert.ImplicitConversionRequired (ec, right, l, loc);
2477                                                         if (tmp == null)
2478                                                                 return null;
2479                                                         right = tmp;
2480                                                         r = right.Type;
2481                                                 }
2482                                         }
2483
2484                                         if (TypeManager.IsDelegateType (r)){
2485                                                 MethodInfo method;
2486                                                 ArrayList args = new ArrayList (2);
2487
2488                                                 args = new ArrayList (2);
2489                                                 args.Add (new Argument (left, Argument.AType.Expression));
2490                                                 args.Add (new Argument (right, Argument.AType.Expression));
2491
2492                                                 if (oper == Operator.Addition)
2493                                                         method = TypeManager.delegate_combine_delegate_delegate;
2494                                                 else
2495                                                         method = TypeManager.delegate_remove_delegate_delegate;
2496
2497                                                 if (!TypeManager.IsEqual (l, r)) {
2498                                                         Error_OperatorCannotBeApplied ();
2499                                                         return null;
2500                                                 }
2501
2502                                                 return new BinaryDelegate (l, method, args);
2503                                         }
2504                                 }
2505
2506                                 //
2507                                 // Pointer arithmetic:
2508                                 //
2509                                 // T* operator + (T* x, int y);
2510                                 // T* operator + (T* x, uint y);
2511                                 // T* operator + (T* x, long y);
2512                                 // T* operator + (T* x, ulong y);
2513                                 //
2514                                 // T* operator + (int y,   T* x);
2515                                 // T* operator + (uint y,  T *x);
2516                                 // T* operator + (long y,  T *x);
2517                                 // T* operator + (ulong y, T *x);
2518                                 //
2519                                 // T* operator - (T* x, int y);
2520                                 // T* operator - (T* x, uint y);
2521                                 // T* operator - (T* x, long y);
2522                                 // T* operator - (T* x, ulong y);
2523                                 //
2524                                 // long operator - (T* x, T *y)
2525                                 //
2526                                 if (l.IsPointer){
2527                                         if (r.IsPointer && oper == Operator.Subtraction){
2528                                                 if (r == l)
2529                                                         return new PointerArithmetic (
2530                                                                 false, left, right, TypeManager.int64_type,
2531                                                                 loc).Resolve (ec);
2532                                         } else {
2533                                                 Expression t = Make32or64 (ec, right);
2534                                                 if (t != null)
2535                                                         return new PointerArithmetic (oper == Operator.Addition, left, t, l, loc).Resolve (ec);
2536                                         }
2537                                 } else if (r.IsPointer && oper == Operator.Addition){
2538                                         Expression t = Make32or64 (ec, left);
2539                                         if (t != null)
2540                                                 return new PointerArithmetic (true, right, t, r, loc).Resolve (ec);
2541                                 }
2542                         }
2543
2544                         //
2545                         // Enumeration operators
2546                         //
2547                         bool lie = TypeManager.IsEnumType (l);
2548                         bool rie = TypeManager.IsEnumType (r);
2549                         if (lie || rie){
2550                                 Expression temp;
2551
2552                                 // U operator - (E e, E f)
2553                                 if (lie && rie){
2554                                         if (oper == Operator.Subtraction){
2555                                         if (l == r){
2556                                                 type = TypeManager.EnumToUnderlying (l);
2557                                                 return this;
2558                                         }
2559                                         Error_OperatorCannotBeApplied ();
2560                                         return null;
2561                                 }
2562                                 }
2563
2564                                 //
2565                                 // operator + (E e, U x)
2566                                 // operator - (E e, U x)
2567                                 //
2568                                 if (oper == Operator.Addition || oper == Operator.Subtraction){
2569                                         Type enum_type = lie ? l : r;
2570                                         Type other_type = lie ? r : l;
2571                                         Type underlying_type = TypeManager.EnumToUnderlying (enum_type);
2572
2573                                         if (underlying_type != other_type){
2574                                                 temp = Convert.ImplicitConversion (ec, lie ? right : left, underlying_type, loc);
2575                                                 if (temp != null){
2576                                                         if (lie)
2577                                                                 right = temp;
2578                                                         else
2579                                                                 left = temp;
2580                                                         type = enum_type;
2581                                                         return this;
2582                                                 }
2583
2584                                                 Error_OperatorCannotBeApplied ();
2585                                                 return null;
2586                                         }
2587
2588                                         type = enum_type;
2589                                         return this;
2590                                 }
2591
2592                                 if (!rie){
2593                                         temp = Convert.ImplicitConversion (ec, right, l, loc);
2594                                         if (temp != null)
2595                                                 right = temp;
2596                                         else {
2597                                                 Error_OperatorCannotBeApplied ();
2598                                                 return null;
2599                                         }
2600                                 } if (!lie){
2601                                         temp = Convert.ImplicitConversion (ec, left, r, loc);
2602                                         if (temp != null){
2603                                                 left = temp;
2604                                                 l = r;
2605                                         } else {
2606                                                 Error_OperatorCannotBeApplied ();
2607                                                 return null;
2608                                         }
2609                                 }
2610
2611                                 if (oper == Operator.Equality || oper == Operator.Inequality ||
2612                                     oper == Operator.LessThanOrEqual || oper == Operator.LessThan ||
2613                                     oper == Operator.GreaterThanOrEqual || oper == Operator.GreaterThan){
2614                                         if (left.Type != right.Type){
2615                                                 Error_OperatorCannotBeApplied ();
2616                                                 return null;
2617                                         }
2618                                         type = TypeManager.bool_type;
2619                                         return this;
2620                                 }
2621
2622                                 if (oper == Operator.BitwiseAnd ||
2623                                     oper == Operator.BitwiseOr ||
2624                                     oper == Operator.ExclusiveOr){
2625                                         if (left.Type != right.Type){
2626                                                 Error_OperatorCannotBeApplied ();
2627                                                 return null;
2628                                         }
2629                                         type = l;
2630                                         return this;
2631                                 }
2632                                 Error_OperatorCannotBeApplied ();
2633                                 return null;
2634                         }
2635
2636                         if (oper == Operator.LeftShift || oper == Operator.RightShift)
2637                                 return CheckShiftArguments (ec);
2638
2639                         if (oper == Operator.LogicalOr || oper == Operator.LogicalAnd){
2640                                 if (l == TypeManager.bool_type && r == TypeManager.bool_type) {
2641                                         type = TypeManager.bool_type;
2642                                         return this;
2643                                 }
2644
2645                                 if (l != r) {
2646                                         Error_OperatorCannotBeApplied ();
2647                                         return null;
2648                                 }
2649
2650                                 Expression e = new ConditionalLogicalOperator (
2651                                         oper == Operator.LogicalAnd, left, right, l, loc);
2652                                 return e.Resolve (ec);
2653                         }
2654
2655                         //
2656                         // operator & (bool x, bool y)
2657                         // operator | (bool x, bool y)
2658                         // operator ^ (bool x, bool y)
2659                         //
2660                         if (l == TypeManager.bool_type && r == TypeManager.bool_type){
2661                                 if (oper == Operator.BitwiseAnd ||
2662                                     oper == Operator.BitwiseOr ||
2663                                     oper == Operator.ExclusiveOr){
2664                                         type = l;
2665                                         return this;
2666                                 }
2667                         }
2668
2669                         //
2670                         // Pointer comparison
2671                         //
2672                         if (l.IsPointer && r.IsPointer){
2673                                 if (oper == Operator.Equality || oper == Operator.Inequality ||
2674                                     oper == Operator.LessThan || oper == Operator.LessThanOrEqual ||
2675                                     oper == Operator.GreaterThan || oper == Operator.GreaterThanOrEqual){
2676                                         type = TypeManager.bool_type;
2677                                         return this;
2678                                 }
2679                         }
2680
2681                         //
2682                         // This will leave left or right set to null if there is an error
2683                         //
2684                         bool check_user_conv = is_user_defined (l) && is_user_defined (r);
2685                         DoNumericPromotions (ec, l, r, check_user_conv);
2686                         if (left == null || right == null){
2687                                 Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
2688                                 return null;
2689                         }
2690
2691                         //
2692                         // reload our cached types if required
2693                         //
2694                         l = left.Type;
2695                         r = right.Type;
2696
2697                         if (oper == Operator.BitwiseAnd ||
2698                             oper == Operator.BitwiseOr ||
2699                             oper == Operator.ExclusiveOr){
2700                                 if (l == r){
2701                                         if (((l == TypeManager.int32_type) ||
2702                                              (l == TypeManager.uint32_type) ||
2703                                              (l == TypeManager.short_type) ||
2704                                              (l == TypeManager.ushort_type) ||
2705                                              (l == TypeManager.int64_type) ||
2706                                              (l == TypeManager.uint64_type))){
2707                                                 type = l;
2708                                         } else {
2709                                                 Error_OperatorCannotBeApplied ();
2710                                                 return null;
2711                                         }
2712                                 } else {
2713                                         Error_OperatorCannotBeApplied ();
2714                                         return null;
2715                                 }
2716                         }
2717
2718                         if (oper == Operator.Equality ||
2719                             oper == Operator.Inequality ||
2720                             oper == Operator.LessThanOrEqual ||
2721                             oper == Operator.LessThan ||
2722                             oper == Operator.GreaterThanOrEqual ||
2723                             oper == Operator.GreaterThan){
2724                                 type = TypeManager.bool_type;
2725                         }
2726
2727                         return this;
2728                 }
2729
2730                 public override Expression DoResolve (EmitContext ec)
2731                 {
2732                         if ((oper == Operator.Subtraction) && (left is ParenthesizedExpression)) {
2733                                 left = ((ParenthesizedExpression) left).Expr;
2734                                 left = left.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.Type);
2735                                 if (left == null)
2736                                         return null;
2737
2738                                 if (left.eclass == ExprClass.Type) {
2739                                         Error (75, "Casting a negative value needs to have the value in parentheses.");
2740                                         return null;
2741                                 }
2742                         } else
2743                                 left = left.Resolve (ec);
2744
2745                         if (left == null)
2746                                 return null;
2747
2748                         Constant lc = left as Constant;
2749                         if (lc != null && lc.Type == TypeManager.bool_type &&
2750                                 ((oper == Operator.LogicalAnd && (bool)lc.GetValue () == false) ||
2751                                  (oper == Operator.LogicalOr && (bool)lc.GetValue () == true))) {
2752
2753                                 // TODO: make a sense to resolve unreachable expression as we do for statement
2754                                 Report.Warning (429, 4, loc, "Unreachable expression code detected");
2755                                 return left;
2756                         }
2757
2758                         right = right.Resolve (ec);
2759                         if (right == null)
2760                                 return null;
2761
2762                         eclass = ExprClass.Value;
2763
2764                         Constant rc = right as Constant;
2765                         if (rc != null & lc != null){
2766                                 Expression e = ConstantFold.BinaryFold (
2767                                         ec, oper, lc, rc, loc);
2768                                         if (e != null)
2769                                                 return e;
2770                         }
2771
2772                         if (TypeManager.IsNullableType (left.Type) || TypeManager.IsNullableType (right.Type))
2773                                 return new Nullable.LiftedBinaryOperator (oper, left, right, loc).Resolve (ec);
2774
2775                         return ResolveOperator (ec);
2776                 }
2777
2778                 /// <remarks>
2779                 ///   EmitBranchable is called from Statement.EmitBoolExpression in the
2780                 ///   context of a conditional bool expression.  This function will return
2781                 ///   false if it is was possible to use EmitBranchable, or true if it was.
2782                 ///
2783                 ///   The expression's code is generated, and we will generate a branch to `target'
2784                 ///   if the resulting expression value is equal to isTrue
2785                 /// </remarks>
2786                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
2787                 {
2788                         ILGenerator ig = ec.ig;
2789
2790                         //
2791                         // This is more complicated than it looks, but its just to avoid
2792                         // duplicated tests: basically, we allow ==, !=, >, <, >= and <=
2793                         // but on top of that we want for == and != to use a special path
2794                         // if we are comparing against null
2795                         //
2796                         if ((oper == Operator.Equality || oper == Operator.Inequality) && (left is Constant || right is Constant)) {
2797                                 bool my_on_true = oper == Operator.Inequality ? onTrue : !onTrue;
2798
2799                                 //
2800                                 // put the constant on the rhs, for simplicity
2801                                 //
2802                                 if (left is Constant) {
2803                                         Expression swap = right;
2804                                         right = left;
2805                                         left = swap;
2806                                 }
2807
2808                                 if (((Constant) right).IsZeroInteger) {
2809                                         left.Emit (ec);
2810                                         if (my_on_true)
2811                                                 ig.Emit (OpCodes.Brtrue, target);
2812                                         else
2813                                                 ig.Emit (OpCodes.Brfalse, target);
2814
2815                                         return;
2816                                 } else if (right is BoolConstant){
2817                                         left.Emit (ec);
2818                                         if (my_on_true != ((BoolConstant) right).Value)
2819                                                 ig.Emit (OpCodes.Brtrue, target);
2820                                         else
2821                                                 ig.Emit (OpCodes.Brfalse, target);
2822
2823                                         return;
2824                                 }
2825
2826                         } else if (oper == Operator.LogicalAnd) {
2827
2828                                 if (onTrue) {
2829                                                 Label tests_end = ig.DefineLabel ();
2830
2831                                         left.EmitBranchable (ec, tests_end, false);
2832                                         right.EmitBranchable (ec, target, true);
2833                                                         ig.MarkLabel (tests_end);
2834                                         } else {
2835                                         left.EmitBranchable (ec, target, false);
2836                                         right.EmitBranchable (ec, target, false);
2837                                         }
2838
2839                                 return;
2840
2841                         } else if (oper == Operator.LogicalOr){
2842                                 if (onTrue) {
2843                                         left.EmitBranchable (ec, target, true);
2844                                         right.EmitBranchable (ec, target, true);
2845
2846                                         } else {
2847                                                 Label tests_end = ig.DefineLabel ();
2848                                         left.EmitBranchable (ec, tests_end, true);
2849                                         right.EmitBranchable (ec, target, false);
2850                                         ig.MarkLabel (tests_end);
2851                                 }
2852
2853                                 return;
2854
2855                         } else if (!(oper == Operator.LessThan        || oper == Operator.GreaterThan ||
2856                                      oper == Operator.LessThanOrEqual || oper == Operator.GreaterThanOrEqual ||
2857                                      oper == Operator.Equality        || oper == Operator.Inequality)) {
2858                                 base.EmitBranchable (ec, target, onTrue);
2859                                 return;
2860                                 }
2861
2862                         left.Emit (ec);
2863                         right.Emit (ec);
2864
2865                         Type t = left.Type;
2866                         bool isUnsigned = is_unsigned (t) || t == TypeManager.double_type || t == TypeManager.float_type;
2867
2868                         switch (oper){
2869                         case Operator.Equality:
2870                                 if (onTrue)
2871                                         ig.Emit (OpCodes.Beq, target);
2872                                 else
2873                                         ig.Emit (OpCodes.Bne_Un, target);
2874                                 break;
2875
2876                         case Operator.Inequality:
2877                                 if (onTrue)
2878                                         ig.Emit (OpCodes.Bne_Un, target);
2879                                 else
2880                                         ig.Emit (OpCodes.Beq, target);
2881                                 break;
2882
2883                         case Operator.LessThan:
2884                                 if (onTrue)
2885                                         if (isUnsigned)
2886                                                 ig.Emit (OpCodes.Blt_Un, target);
2887                                         else
2888                                                 ig.Emit (OpCodes.Blt, target);
2889                                 else
2890                                         if (isUnsigned)
2891                                                 ig.Emit (OpCodes.Bge_Un, target);
2892                                         else
2893                                                 ig.Emit (OpCodes.Bge, target);
2894                                 break;
2895
2896                         case Operator.GreaterThan:
2897                                 if (onTrue)
2898                                         if (isUnsigned)
2899                                                 ig.Emit (OpCodes.Bgt_Un, target);
2900                                         else
2901                                                 ig.Emit (OpCodes.Bgt, target);
2902                                 else
2903                                         if (isUnsigned)
2904                                                 ig.Emit (OpCodes.Ble_Un, target);
2905                                         else
2906                                                 ig.Emit (OpCodes.Ble, target);
2907                                 break;
2908
2909                         case Operator.LessThanOrEqual:
2910                                 if (onTrue)
2911                                         if (isUnsigned)
2912                                                 ig.Emit (OpCodes.Ble_Un, target);
2913                                         else
2914                                                 ig.Emit (OpCodes.Ble, target);
2915                                 else
2916                                         if (isUnsigned)
2917                                                 ig.Emit (OpCodes.Bgt_Un, target);
2918                                         else
2919                                                 ig.Emit (OpCodes.Bgt, target);
2920                                 break;
2921
2922
2923                         case Operator.GreaterThanOrEqual:
2924                                 if (onTrue)
2925                                         if (isUnsigned)
2926                                                 ig.Emit (OpCodes.Bge_Un, target);
2927                                         else
2928                                                 ig.Emit (OpCodes.Bge, target);
2929                                 else
2930                                         if (isUnsigned)
2931                                                 ig.Emit (OpCodes.Blt_Un, target);
2932                                         else
2933                                                 ig.Emit (OpCodes.Blt, target);
2934                                 break;
2935                         default:
2936                                 Console.WriteLine (oper);
2937                                 throw new Exception ("what is THAT");
2938                         }
2939                 }
2940
2941                 public override void Emit (EmitContext ec)
2942                 {
2943                         ILGenerator ig = ec.ig;
2944                         Type l = left.Type;
2945                         OpCode opcode;
2946
2947                         //
2948                         // Handle short-circuit operators differently
2949                         // than the rest
2950                         //
2951                         if (oper == Operator.LogicalAnd) {
2952                                 Label load_zero = ig.DefineLabel ();
2953                                 Label end = ig.DefineLabel ();
2954
2955                                 left.EmitBranchable (ec, load_zero, false);
2956                                                 right.Emit (ec);
2957                                                 ig.Emit (OpCodes.Br, end);
2958
2959                                 ig.MarkLabel (load_zero);
2960                                 ig.Emit (OpCodes.Ldc_I4_0);
2961                                 ig.MarkLabel (end);
2962                                 return;
2963                         } else if (oper == Operator.LogicalOr) {
2964                                 Label load_one = ig.DefineLabel ();
2965                                 Label end = ig.DefineLabel ();
2966
2967                                 left.EmitBranchable (ec, load_one, true);
2968                                                 right.Emit (ec);
2969                                                 ig.Emit (OpCodes.Br, end);
2970
2971                                 ig.MarkLabel (load_one);
2972                                 ig.Emit (OpCodes.Ldc_I4_1);
2973                                 ig.MarkLabel (end);
2974                                 return;
2975                         }
2976
2977                         left.Emit (ec);
2978                         right.Emit (ec);
2979
2980                         bool isUnsigned = is_unsigned (left.Type);
2981
2982                         switch (oper){
2983                         case Operator.Multiply:
2984                                 if (ec.CheckState){
2985                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
2986                                                 opcode = OpCodes.Mul_Ovf;
2987                                         else if (isUnsigned)
2988                                                 opcode = OpCodes.Mul_Ovf_Un;
2989                                         else
2990                                                 opcode = OpCodes.Mul;
2991                                 } else
2992                                         opcode = OpCodes.Mul;
2993
2994                                 break;
2995
2996                         case Operator.Division:
2997                                 if (isUnsigned)
2998                                         opcode = OpCodes.Div_Un;
2999                                 else
3000                                         opcode = OpCodes.Div;
3001                                 break;
3002
3003                         case Operator.Modulus:
3004                                 if (isUnsigned)
3005                                         opcode = OpCodes.Rem_Un;
3006                                 else
3007                                         opcode = OpCodes.Rem;
3008                                 break;
3009
3010                         case Operator.Addition:
3011                                 if (ec.CheckState){
3012                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
3013                                                 opcode = OpCodes.Add_Ovf;
3014                                         else if (isUnsigned)
3015                                                 opcode = OpCodes.Add_Ovf_Un;
3016                                         else
3017                                                 opcode = OpCodes.Add;
3018                                 } else
3019                                         opcode = OpCodes.Add;
3020                                 break;
3021
3022                         case Operator.Subtraction:
3023                                 if (ec.CheckState){
3024                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
3025                                                 opcode = OpCodes.Sub_Ovf;
3026                                         else if (isUnsigned)
3027                                                 opcode = OpCodes.Sub_Ovf_Un;
3028                                         else
3029                                                 opcode = OpCodes.Sub;
3030                                 } else
3031                                         opcode = OpCodes.Sub;
3032                                 break;
3033
3034                         case Operator.RightShift:
3035                                 if (isUnsigned)
3036                                         opcode = OpCodes.Shr_Un;
3037                                 else
3038                                         opcode = OpCodes.Shr;
3039                                 break;
3040
3041                         case Operator.LeftShift:
3042                                 opcode = OpCodes.Shl;
3043                                 break;
3044
3045                         case Operator.Equality:
3046                                 opcode = OpCodes.Ceq;
3047                                 break;
3048
3049                         case Operator.Inequality:
3050                                 ig.Emit (OpCodes.Ceq);
3051                                 ig.Emit (OpCodes.Ldc_I4_0);
3052
3053                                 opcode = OpCodes.Ceq;
3054                                 break;
3055
3056                         case Operator.LessThan:
3057                                 if (isUnsigned)
3058                                         opcode = OpCodes.Clt_Un;
3059                                 else
3060                                         opcode = OpCodes.Clt;
3061                                 break;
3062
3063                         case Operator.GreaterThan:
3064                                 if (isUnsigned)
3065                                         opcode = OpCodes.Cgt_Un;
3066                                 else
3067                                         opcode = OpCodes.Cgt;
3068                                 break;
3069
3070                         case Operator.LessThanOrEqual:
3071                                 Type lt = left.Type;
3072
3073                                 if (isUnsigned || (lt == TypeManager.double_type || lt == TypeManager.float_type))
3074                                         ig.Emit (OpCodes.Cgt_Un);
3075                                 else
3076                                         ig.Emit (OpCodes.Cgt);
3077                                 ig.Emit (OpCodes.Ldc_I4_0);
3078
3079                                 opcode = OpCodes.Ceq;
3080                                 break;
3081
3082                         case Operator.GreaterThanOrEqual:
3083                                 Type le = left.Type;
3084
3085                                 if (isUnsigned || (le == TypeManager.double_type || le == TypeManager.float_type))
3086                                         ig.Emit (OpCodes.Clt_Un);
3087                                 else
3088                                         ig.Emit (OpCodes.Clt);
3089
3090                                 ig.Emit (OpCodes.Ldc_I4_0);
3091
3092                                 opcode = OpCodes.Ceq;
3093                                 break;
3094
3095                         case Operator.BitwiseOr:
3096                                 opcode = OpCodes.Or;
3097                                 break;
3098
3099                         case Operator.BitwiseAnd:
3100                                 opcode = OpCodes.And;
3101                                 break;
3102
3103                         case Operator.ExclusiveOr:
3104                                 opcode = OpCodes.Xor;
3105                                 break;
3106
3107                         default:
3108                                 throw new Exception ("This should not happen: Operator = "
3109                                                      + oper.ToString ());
3110                         }
3111
3112                         ig.Emit (opcode);
3113                 }
3114         }
3115
3116         //
3117         // Object created by Binary when the binary operator uses an method instead of being
3118         // a binary operation that maps to a CIL binary operation.
3119         //
3120         public class BinaryMethod : Expression {
3121                 public MethodBase method;
3122                 public ArrayList  Arguments;
3123
3124                 public BinaryMethod (Type t, MethodBase m, ArrayList args)
3125                 {
3126                         method = m;
3127                         Arguments = args;
3128                         type = t;
3129                         eclass = ExprClass.Value;
3130                 }
3131
3132                 public override Expression DoResolve (EmitContext ec)
3133                 {
3134                         return this;
3135                 }
3136
3137                 public override void Emit (EmitContext ec)
3138                 {
3139                         ILGenerator ig = ec.ig;
3140
3141                         if (Arguments != null)
3142                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
3143
3144                         if (method is MethodInfo)
3145                                 ig.Emit (OpCodes.Call, (MethodInfo) method);
3146                         else
3147                                 ig.Emit (OpCodes.Call, (ConstructorInfo) method);
3148                 }
3149         }
3150
3151         //
3152         // Represents the operation a + b [+ c [+ d [+ ...]]], where a is a string
3153         // b, c, d... may be strings or objects.
3154         //
3155         public class StringConcat : Expression {
3156                 ArrayList operands;
3157                 bool invalid = false;
3158                 bool emit_conv_done = false;
3159                 //
3160                 // Are we also concating objects?
3161                 //
3162                 bool is_strings_only = true;
3163
3164                 public StringConcat (EmitContext ec, Location loc, Expression left, Expression right)
3165                 {
3166                         this.loc = loc;
3167                         type = TypeManager.string_type;
3168                         eclass = ExprClass.Value;
3169
3170                         operands = new ArrayList (2);
3171                         Append (ec, left);
3172                         Append (ec, right);
3173                 }
3174
3175                 public override Expression DoResolve (EmitContext ec)
3176                 {
3177                         if (invalid)
3178                                 return null;
3179
3180                         return this;
3181                 }
3182
3183                 public void Append (EmitContext ec, Expression operand)
3184                 {
3185                         //
3186                         // Constant folding
3187                         //
3188                         if (operand is StringConstant && operands.Count != 0) {
3189                                 StringConstant last_operand = operands [operands.Count - 1] as StringConstant;
3190                                 if (last_operand != null) {
3191                                         operands [operands.Count - 1] = new StringConstant (last_operand.Value + ((StringConstant) operand).Value);
3192                                         return;
3193                                 }
3194                         }
3195
3196                         //
3197                         // Conversion to object
3198                         //
3199                         if (operand.Type != TypeManager.string_type) {
3200                                 Expression no = Convert.ImplicitConversion (ec, operand, TypeManager.object_type, loc);
3201
3202                                 if (no == null) {
3203                                         Binary.Error_OperatorCannotBeApplied (loc, "+", TypeManager.string_type, operand.Type);
3204                                         invalid = true;
3205                                 }
3206                                 operand = no;
3207                         }
3208
3209                         operands.Add (operand);
3210                 }
3211
3212                 public override void Emit (EmitContext ec)
3213                 {
3214                         MethodInfo concat_method = null;
3215
3216                         //
3217                         // Do conversion to arguments; check for strings only
3218                         //
3219
3220                         // This can get called multiple times, so we have to deal with that.
3221                         if (!emit_conv_done) {
3222                                 emit_conv_done = true;
3223                         for (int i = 0; i < operands.Count; i ++) {
3224                                 Expression e = (Expression) operands [i];
3225                                 is_strings_only &= e.Type == TypeManager.string_type;
3226                         }
3227
3228                         for (int i = 0; i < operands.Count; i ++) {
3229                                 Expression e = (Expression) operands [i];
3230
3231                                 if (! is_strings_only && e.Type == TypeManager.string_type) {
3232                                         // need to make sure this is an object, because the EmitParams
3233                                         // method might look at the type of this expression, see it is a
3234                                         // string and emit a string [] when we want an object [];
3235
3236                                                 e = new EmptyCast (e, TypeManager.object_type);
3237                                 }
3238                                 operands [i] = new Argument (e, Argument.AType.Expression);
3239                         }
3240                         }
3241
3242                         //
3243                         // Find the right method
3244                         //
3245                         switch (operands.Count) {
3246                         case 1:
3247                                 //
3248                                 // This should not be possible, because simple constant folding
3249                                 // is taken care of in the Binary code.
3250                                 //
3251                                 throw new Exception ("how did you get here?");
3252
3253                         case 2:
3254                                 concat_method = is_strings_only ?
3255                                         TypeManager.string_concat_string_string :
3256                                         TypeManager.string_concat_object_object ;
3257                                 break;
3258                         case 3:
3259                                 concat_method = is_strings_only ?
3260                                         TypeManager.string_concat_string_string_string :
3261                                         TypeManager.string_concat_object_object_object ;
3262                                 break;
3263                         case 4:
3264                                 //
3265                                 // There is not a 4 param overlaod for object (the one that there is
3266                                 // is actually a varargs methods, and is only in corlib because it was
3267                                 // introduced there before.).
3268                                 //
3269                                 if (!is_strings_only)
3270                                         goto default;
3271
3272                                 concat_method = TypeManager.string_concat_string_string_string_string;
3273                                 break;
3274                         default:
3275                                 concat_method = is_strings_only ?
3276                                         TypeManager.string_concat_string_dot_dot_dot :
3277                                         TypeManager.string_concat_object_dot_dot_dot ;
3278                                 break;
3279                         }
3280
3281                         Invocation.EmitArguments (ec, concat_method, operands, false, null);
3282                         ec.ig.Emit (OpCodes.Call, concat_method);
3283                 }
3284         }
3285
3286         //
3287         // Object created with +/= on delegates
3288         //
3289         public class BinaryDelegate : Expression {
3290                 MethodInfo method;
3291                 ArrayList  args;
3292
3293                 public BinaryDelegate (Type t, MethodInfo mi, ArrayList args)
3294                 {
3295                         method = mi;
3296                         this.args = args;
3297                         type = t;
3298                         eclass = ExprClass.Value;
3299                 }
3300
3301                 public override Expression DoResolve (EmitContext ec)
3302                 {
3303                         return this;
3304                 }
3305
3306                 public override void Emit (EmitContext ec)
3307                 {
3308                         ILGenerator ig = ec.ig;
3309
3310                         Invocation.EmitArguments (ec, method, args, false, null);
3311
3312                         ig.Emit (OpCodes.Call, (MethodInfo) method);
3313                         ig.Emit (OpCodes.Castclass, type);
3314                 }
3315
3316                 public Expression Right {
3317                         get {
3318                                 Argument arg = (Argument) args [1];
3319                                 return arg.Expr;
3320                         }
3321                 }
3322
3323                 public bool IsAddition {
3324                         get {
3325                                 return method == TypeManager.delegate_combine_delegate_delegate;
3326                         }
3327                 }
3328         }
3329
3330         //
3331         // User-defined conditional logical operator
3332         public class ConditionalLogicalOperator : Expression {
3333                 Expression left, right;
3334                 bool is_and;
3335
3336                 public ConditionalLogicalOperator (bool is_and, Expression left, Expression right, Type t, Location loc)
3337                 {
3338                         type = t;
3339                         eclass = ExprClass.Value;
3340                         this.loc = loc;
3341                         this.left = left;
3342                         this.right = right;
3343                         this.is_and = is_and;
3344                 }
3345
3346                 protected void Error19 ()
3347                 {
3348                         Binary.Error_OperatorCannotBeApplied (loc, is_and ? "&&" : "||", type, type);
3349                 }
3350
3351                 protected void Error218 ()
3352                 {
3353                         Error (218, "The type ('" + TypeManager.CSharpName (type) + "') must contain " +
3354                                "declarations of operator true and operator false");
3355                 }
3356
3357                 Expression op_true, op_false, op;
3358                 LocalTemporary left_temp;
3359
3360                 public override Expression DoResolve (EmitContext ec)
3361                 {
3362                         MethodInfo method;
3363                         Expression operator_group;
3364
3365                         operator_group = MethodLookup (ec, type, is_and ? "op_BitwiseAnd" : "op_BitwiseOr", loc);
3366                         if (operator_group == null) {
3367                                 Error19 ();
3368                                 return null;
3369                         }
3370
3371                         left_temp = new LocalTemporary (ec, type);
3372
3373                         ArrayList arguments = new ArrayList ();
3374                         arguments.Add (new Argument (left_temp, Argument.AType.Expression));
3375                         arguments.Add (new Argument (right, Argument.AType.Expression));
3376                         method = Invocation.OverloadResolve (
3377                                 ec, (MethodGroupExpr) operator_group, arguments, false, loc)
3378                                 as MethodInfo;
3379                         if (method == null) {
3380                                 Error19 ();
3381                                 return null;
3382                         }
3383
3384                         if (method.ReturnType != type) {
3385                                 Report.Error (217, loc, "In order to be applicable as a short circuit operator a user-defined logical operator ('{0}') " +
3386                                                 "must have the same return type as the type of its 2 parameters", TypeManager.CSharpSignature (method));
3387                                 return null;
3388                         }
3389
3390                         op = new StaticCallExpr (method, arguments, loc);
3391
3392                         op_true = GetOperatorTrue (ec, left_temp, loc);
3393                         op_false = GetOperatorFalse (ec, left_temp, loc);
3394                         if ((op_true == null) || (op_false == null)) {
3395                                 Error218 ();
3396                                 return null;
3397                         }
3398
3399                         return this;
3400                 }
3401
3402                 public override void Emit (EmitContext ec)
3403                 {
3404                         ILGenerator ig = ec.ig;
3405                         Label false_target = ig.DefineLabel ();
3406                         Label end_target = ig.DefineLabel ();
3407
3408                         left.Emit (ec);
3409                         left_temp.Store (ec);
3410
3411                         (is_and ? op_false : op_true).EmitBranchable (ec, false_target, false);
3412                         left_temp.Emit (ec);
3413                         ig.Emit (OpCodes.Br, end_target);
3414                         ig.MarkLabel (false_target);
3415                         op.Emit (ec);
3416                         ig.MarkLabel (end_target);
3417                 }
3418         }
3419
3420         public class PointerArithmetic : Expression {
3421                 Expression left, right;
3422                 bool is_add;
3423
3424                 //
3425                 // We assume that `l' is always a pointer
3426                 //
3427                 public PointerArithmetic (bool is_addition, Expression l, Expression r, Type t, Location loc)
3428                 {
3429                         type = t;
3430                         this.loc = loc;
3431                         left = l;
3432                         right = r;
3433                         is_add = is_addition;
3434                 }
3435
3436                 public override Expression DoResolve (EmitContext ec)
3437                 {
3438                         eclass = ExprClass.Variable;
3439
3440                         if (left.Type == TypeManager.void_ptr_type) {
3441                                 Error (242, "The operation in question is undefined on void pointers");
3442                                 return null;
3443                         }
3444
3445                         return this;
3446                 }
3447
3448                 public override void Emit (EmitContext ec)
3449                 {
3450                         Type op_type = left.Type;
3451                         ILGenerator ig = ec.ig;
3452
3453                         // It must be either array or fixed buffer
3454                         Type element = TypeManager.HasElementType (op_type) ?
3455                                 element = TypeManager.GetElementType (op_type) :
3456                                 element = AttributeTester.GetFixedBuffer (((FieldExpr)left).FieldInfo).ElementType;
3457
3458                         int size = GetTypeSize (element);
3459                         Type rtype = right.Type;
3460
3461                         if (rtype.IsPointer){
3462                                 //
3463                                 // handle (pointer - pointer)
3464                                 //
3465                                 left.Emit (ec);
3466                                 right.Emit (ec);
3467                                 ig.Emit (OpCodes.Sub);
3468
3469                                 if (size != 1){
3470                                         if (size == 0)
3471                                                 ig.Emit (OpCodes.Sizeof, element);
3472                                         else
3473                                                 IntLiteral.EmitInt (ig, size);
3474                                         ig.Emit (OpCodes.Div);
3475                                 }
3476                                 ig.Emit (OpCodes.Conv_I8);
3477                         } else {
3478                                 //
3479                                 // handle + and - on (pointer op int)
3480                                 //
3481                                 left.Emit (ec);
3482                                 ig.Emit (OpCodes.Conv_I);
3483
3484                                 Constant right_const = right as Constant;
3485                                 if (right_const != null && size != 0) {
3486                                         Expression ex = ConstantFold.BinaryFold (ec, Binary.Operator.Multiply, new IntConstant (size), right_const, loc);
3487                                         if (ex == null)
3488                                                 return;
3489                                         ex.Emit (ec);
3490                                 } else {
3491                                         right.Emit (ec);
3492                                         if (size != 1){
3493                                                 if (size == 0)
3494                                                         ig.Emit (OpCodes.Sizeof, element);
3495                                                 else
3496                                                         IntLiteral.EmitInt (ig, size);
3497                                                 if (rtype == TypeManager.int64_type)
3498                                                         ig.Emit (OpCodes.Conv_I8);
3499                                                 else if (rtype == TypeManager.uint64_type)
3500                                                         ig.Emit (OpCodes.Conv_U8);
3501                                                 ig.Emit (OpCodes.Mul);
3502                                         }
3503                                 }
3504
3505                                 if (rtype == TypeManager.int64_type || rtype == TypeManager.uint64_type)
3506                                         ig.Emit (OpCodes.Conv_I);
3507
3508                                 if (is_add)
3509                                         ig.Emit (OpCodes.Add);
3510                                 else
3511                                         ig.Emit (OpCodes.Sub);
3512                         }
3513                 }
3514         }
3515
3516         /// <summary>
3517         ///   Implements the ternary conditional operator (?:)
3518         /// </summary>
3519         public class Conditional : Expression {
3520                 Expression expr, trueExpr, falseExpr;
3521
3522                 public Conditional (Expression expr, Expression trueExpr, Expression falseExpr, Location l)
3523                 {
3524                         this.expr = expr;
3525                         this.trueExpr = trueExpr;
3526                         this.falseExpr = falseExpr;
3527                         this.loc = l;
3528                 }
3529
3530                 public Expression Expr {
3531                         get {
3532                                 return expr;
3533                         }
3534                 }
3535
3536                 public Expression TrueExpr {
3537                         get {
3538                                 return trueExpr;
3539                         }
3540                 }
3541
3542                 public Expression FalseExpr {
3543                         get {
3544                                 return falseExpr;
3545                         }
3546                 }
3547
3548                 public override Expression DoResolve (EmitContext ec)
3549                 {
3550                         expr = expr.Resolve (ec);
3551
3552                         if (expr == null)
3553                                 return null;
3554
3555                         if (TypeManager.IsNullableType (expr.Type))
3556                                 return new Nullable.LiftedConditional (expr, trueExpr, falseExpr, loc).Resolve (ec);
3557
3558                         if (expr.Type != TypeManager.bool_type){
3559                                 expr = Expression.ResolveBoolean (
3560                                         ec, expr, loc);
3561
3562                                 if (expr == null)
3563                                         return null;
3564                         }
3565
3566                         trueExpr = trueExpr.Resolve (ec);
3567                         falseExpr = falseExpr.Resolve (ec);
3568
3569                         if (trueExpr == null || falseExpr == null)
3570                                 return null;
3571
3572                         eclass = ExprClass.Value;
3573                         if (trueExpr.Type == falseExpr.Type)
3574                                 type = trueExpr.Type;
3575                         else {
3576                                 Expression conv;
3577                                 Type true_type = trueExpr.Type;
3578                                 Type false_type = falseExpr.Type;
3579
3580                                 //
3581                                 // First, if an implicit conversion exists from trueExpr
3582                                 // to falseExpr, then the result type is of type falseExpr.Type
3583                                 //
3584                                 conv = Convert.ImplicitConversion (ec, trueExpr, false_type, loc);
3585                                 if (conv != null){
3586                                         //
3587                                         // Check if both can convert implicitl to each other's type
3588                                         //
3589                                         if (Convert.ImplicitConversion (ec, falseExpr, true_type, loc) != null){
3590                                                 Error (172,
3591                                                        "Can not compute type of conditional expression " +
3592                                                        "as `" + TypeManager.CSharpName (trueExpr.Type) +
3593                                                        "' and `" + TypeManager.CSharpName (falseExpr.Type) +
3594                                                        "' convert implicitly to each other");
3595                                                 return null;
3596                                         }
3597                                         type = false_type;
3598                                         trueExpr = conv;
3599                                 } else if ((conv = Convert.ImplicitConversion(ec, falseExpr, true_type,loc))!= null){
3600                                         type = true_type;
3601                                         falseExpr = conv;
3602                                 } else {
3603                                         Error (173, "The type of the conditional expression can " +
3604                                                "not be computed because there is no implicit conversion" +
3605                                                " from `" + TypeManager.CSharpName (trueExpr.Type) + "'" +
3606                                                " and `" + TypeManager.CSharpName (falseExpr.Type) + "'");
3607                                         return null;
3608                                 }
3609                         }
3610
3611                         // Dead code optimalization
3612                         if (expr is BoolConstant){
3613                                 BoolConstant bc = (BoolConstant) expr;
3614
3615                                 Report.Warning (429, 4, bc.Value ? falseExpr.Location : trueExpr.Location, "Unreachable expression code detected");
3616                                 return bc.Value ? trueExpr : falseExpr;
3617                         }
3618
3619                         return this;
3620                 }
3621
3622                 public override void Emit (EmitContext ec)
3623                 {
3624                         ILGenerator ig = ec.ig;
3625                         Label false_target = ig.DefineLabel ();
3626                         Label end_target = ig.DefineLabel ();
3627
3628                         expr.EmitBranchable (ec, false_target, false);
3629                         trueExpr.Emit (ec);
3630                         ig.Emit (OpCodes.Br, end_target);
3631                         ig.MarkLabel (false_target);
3632                         falseExpr.Emit (ec);
3633                         ig.MarkLabel (end_target);
3634                 }
3635
3636         }
3637
3638         /// <summary>
3639         ///   Local variables
3640         /// </summary>
3641         public class LocalVariableReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
3642                 public readonly string Name;
3643                 public readonly Block Block;
3644                 public LocalInfo local_info;
3645                 bool is_readonly;
3646                 bool prepared;
3647                 LocalTemporary temp;
3648
3649                 public LocalVariableReference (Block block, string name, Location l)
3650                 {
3651                         Block = block;
3652                         Name = name;
3653                         loc = l;
3654                         eclass = ExprClass.Variable;
3655                 }
3656
3657                 //
3658                 // Setting `is_readonly' to false will allow you to create a writable
3659                 // reference to a read-only variable.  This is used by foreach and using.
3660                 //
3661                 public LocalVariableReference (Block block, string name, Location l,
3662                                                LocalInfo local_info, bool is_readonly)
3663                         : this (block, name, l)
3664                 {
3665                         this.local_info = local_info;
3666                         this.is_readonly = is_readonly;
3667                 }
3668
3669                 public VariableInfo VariableInfo {
3670                         get {
3671                                 return local_info.VariableInfo;
3672                         }
3673                 }
3674
3675                 public bool IsReadOnly {
3676                         get {
3677                                 return is_readonly;
3678                         }
3679                 }
3680
3681                 protected Expression DoResolveBase (EmitContext ec, Expression lvalue_right_side)
3682                 {
3683                         if (local_info == null) {
3684                                 local_info = Block.GetLocalInfo (Name);
3685
3686                                 // is out param
3687                                 if (lvalue_right_side == EmptyExpression.Null)
3688                                         local_info.Used = true;
3689
3690                                 is_readonly = local_info.ReadOnly;
3691                         }
3692
3693                         type = local_info.VariableType;
3694
3695                         VariableInfo variable_info = local_info.VariableInfo;
3696                         if (lvalue_right_side != null){
3697                                 if (is_readonly){
3698                                         Error (1604, "cannot assign to `" + Name + "' because it is readonly");
3699                                         return null;
3700                                 }
3701
3702                                 if (variable_info != null)
3703                                         variable_info.SetAssigned (ec);
3704                 }
3705
3706                         Expression e = Block.GetConstantExpression (Name);
3707                         if (e != null) {
3708                                 local_info.Used = true;
3709                                 eclass = ExprClass.Value;
3710                                 return e.Resolve (ec);
3711                         }
3712
3713                         if ((variable_info != null) && !variable_info.IsAssigned (ec, loc))
3714                                 return null;
3715
3716                         if (lvalue_right_side == null)
3717                                 local_info.Used = true;
3718
3719                         if (ec.CurrentAnonymousMethod != null){
3720                                 //
3721                                 // If we are referencing a variable from the external block
3722                                 // flag it for capturing
3723                                 //
3724                                 if (local_info.Block.Toplevel != ec.CurrentBlock.Toplevel){
3725                                         if (local_info.AddressTaken){
3726                                                 AnonymousMethod.Error_AddressOfCapturedVar (local_info.Name, loc);
3727                                                 return null;
3728                                         }
3729                                         ec.CaptureVariable (local_info);
3730                                 }
3731                         }
3732
3733                         return this;
3734                 }
3735
3736                 public override Expression DoResolve (EmitContext ec)
3737                 {
3738                         return DoResolveBase (ec, null);
3739                 }
3740
3741                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
3742                 {
3743                         Expression ret = DoResolveBase (ec, right_side);
3744                         if (ret != null)
3745                                 CheckObsoleteAttribute (ret.Type);
3746
3747                         return ret;
3748                 }
3749
3750                 public bool VerifyFixed (bool is_expression)
3751                 {
3752                         return !is_expression || local_info.IsFixed;
3753                 }
3754
3755                 public override int GetHashCode()
3756                 {
3757                         return Name.GetHashCode ();
3758                 }
3759
3760                 public override bool Equals (object obj)
3761                 {
3762                         LocalVariableReference lvr = obj as LocalVariableReference;
3763                         if (lvr == null)
3764                                 return false;
3765
3766                         return Name == lvr.Name && Block == lvr.Block;
3767                 }
3768
3769                 public override void Emit (EmitContext ec)
3770                 {
3771                         ILGenerator ig = ec.ig;
3772
3773                         if (local_info.FieldBuilder == null){
3774                                 //
3775                                 // A local variable on the local CLR stack
3776                                 //
3777                         ig.Emit (OpCodes.Ldloc, local_info.LocalBuilder);
3778                         } else {
3779                                 //
3780                                 // A local variable captured by anonymous methods.
3781                                 //
3782                                 if (!prepared)
3783                                         ec.EmitCapturedVariableInstance (local_info);
3784
3785                                 ig.Emit (OpCodes.Ldfld, local_info.FieldBuilder);
3786                         }
3787                 }
3788
3789                 public void Emit (EmitContext ec, bool leave_copy)
3790                 {
3791                         Emit (ec);
3792                         if (leave_copy){
3793                                 ec.ig.Emit (OpCodes.Dup);
3794                                 if (local_info.FieldBuilder != null){
3795                                         temp = new LocalTemporary (ec, Type);
3796                                         temp.Store (ec);
3797                                 }
3798                         }
3799                 }
3800
3801                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
3802                 {
3803                         ILGenerator ig = ec.ig;
3804                         prepared = prepare_for_load;
3805
3806                         if (local_info.FieldBuilder == null){
3807                                 //
3808                                 // A local variable on the local CLR stack
3809                                 //
3810                                 if (local_info.LocalBuilder == null)
3811                                         throw new Exception ("This should not happen: both Field and Local are null");
3812
3813                         source.Emit (ec);
3814                         if (leave_copy)
3815                                 ec.ig.Emit (OpCodes.Dup);
3816                                 ig.Emit (OpCodes.Stloc, local_info.LocalBuilder);
3817                         } else {
3818                                 //
3819                                 // A local variable captured by anonymous methods or itereators.
3820                                 //
3821                                 ec.EmitCapturedVariableInstance (local_info);
3822
3823                                 if (prepare_for_load)
3824                                         ig.Emit (OpCodes.Dup);
3825                                 source.Emit (ec);
3826                                 if (leave_copy){
3827                                         ig.Emit (OpCodes.Dup);
3828                                         temp = new LocalTemporary (ec, Type);
3829                                         temp.Store (ec);
3830                                 }
3831                                 ig.Emit (OpCodes.Stfld, local_info.FieldBuilder);
3832                                 if (temp != null)
3833                                         temp.Emit (ec);
3834                         }
3835                 }
3836
3837                 public void AddressOf (EmitContext ec, AddressOp mode)
3838                 {
3839                         ILGenerator ig = ec.ig;
3840
3841                         if (local_info.FieldBuilder == null){
3842                                 //
3843                                 // A local variable on the local CLR stack
3844                                 //
3845                         ig.Emit (OpCodes.Ldloca, local_info.LocalBuilder);
3846                         } else {
3847                                 //
3848                                 // A local variable captured by anonymous methods or iterators
3849                                 //
3850                                 ec.EmitCapturedVariableInstance (local_info);
3851                                 ig.Emit (OpCodes.Ldflda, local_info.FieldBuilder);
3852                         }
3853                 }
3854
3855                 public override string ToString ()
3856                 {
3857                         return String.Format ("{0} ({1}:{2})", GetType (), Name, loc);
3858                 }
3859         }
3860
3861         /// <summary>
3862         ///   This represents a reference to a parameter in the intermediate
3863         ///   representation.
3864         /// </summary>
3865         public class ParameterReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
3866                 Parameters pars;
3867                 String name;
3868                 int idx;
3869                 Block block;
3870                 VariableInfo vi;
3871                 public Parameter.Modifier mod;
3872                 public bool is_ref, is_out, prepared;
3873
3874                 public bool IsOut {
3875                         get {
3876                                 return is_out;
3877                         }
3878                 }
3879
3880                 public bool IsRef {
3881                         get {
3882                                 return is_ref;
3883                         }
3884                 }
3885
3886                 LocalTemporary temp;
3887
3888                 public ParameterReference (Parameters pars, Block block, int idx, string name, Location loc)
3889                 {
3890                         this.pars = pars;
3891                         this.block = block;
3892                         this.idx  = idx;
3893                         this.name = name;
3894                         this.loc = loc;
3895                         eclass = ExprClass.Variable;
3896                 }
3897
3898                 public VariableInfo VariableInfo {
3899                         get { return vi; }
3900                 }
3901
3902                 public bool VerifyFixed (bool is_expression)
3903                 {
3904                         return !is_expression || TypeManager.IsValueType (type);
3905                 }
3906
3907                 public bool IsAssigned (EmitContext ec, Location loc)
3908                 {
3909                         if (!ec.DoFlowAnalysis || !is_out || ec.CurrentBranching.IsAssigned (vi))
3910                                 return true;
3911
3912                         Report.Error (269, loc,
3913                                       "Use of unassigned out parameter '{0}'", name);
3914                         return false;
3915                 }
3916
3917                 public bool IsFieldAssigned (EmitContext ec, string field_name, Location loc)
3918                 {
3919                         if (!ec.DoFlowAnalysis || !is_out || ec.CurrentBranching.IsFieldAssigned (vi, field_name))
3920                                 return true;
3921
3922                         Report.Error (170, loc,
3923                                       "Use of possibly unassigned field `" + field_name + "'");
3924                         return false;
3925                 }
3926
3927                 public void SetAssigned (EmitContext ec)
3928                 {
3929                         if (is_out && ec.DoFlowAnalysis)
3930                                 ec.CurrentBranching.SetAssigned (vi);
3931                 }
3932
3933                 public void SetFieldAssigned (EmitContext ec, string field_name)
3934                 {
3935                         if (is_out && ec.DoFlowAnalysis)
3936                                 ec.CurrentBranching.SetFieldAssigned (vi, field_name);
3937                 }
3938
3939                 protected void DoResolveBase (EmitContext ec)
3940                 {
3941                         type = pars.GetParameterInfo (ec, idx, out mod);
3942                         is_ref = (mod & Parameter.Modifier.ISBYREF) != 0;
3943                         is_out = (mod & Parameter.Modifier.OUT) != 0;
3944                         eclass = ExprClass.Variable;
3945
3946                         if (is_out)
3947                                 vi = block.ParameterMap [idx];
3948
3949                         if (ec.CurrentAnonymousMethod != null){
3950                                 if (is_ref){
3951                                         Report.Error (1628, Location,
3952                                                       "Can not reference a ref or out parameter in an anonymous method");
3953                                         return;
3954                                 }
3955
3956                                 //
3957                                 // If we are referencing the parameter from the external block
3958                                 // flag it for capturing
3959                                 //
3960                                 //Console.WriteLine ("Is parameter `{0}' local? {1}", name, block.IsLocalParameter (name));
3961                                 if (!block.IsLocalParameter (name)){
3962                                         ec.CaptureParameter (name, type, idx);
3963                                 }
3964                         }
3965                 }
3966
3967                 public override int GetHashCode()
3968                 {
3969                         return name.GetHashCode ();
3970                 }
3971
3972                 public override bool Equals (object obj)
3973                 {
3974                         ParameterReference pr = obj as ParameterReference;
3975                         if (pr == null)
3976                                 return false;
3977
3978                         return name == pr.name && block == pr.block;
3979                 }
3980
3981                 //
3982                 // Notice that for ref/out parameters, the type exposed is not the
3983                 // same type exposed externally.
3984                 //
3985                 // for "ref int a":
3986                 //   externally we expose "int&"
3987                 //   here we expose       "int".
3988                 //
3989                 // We record this in "is_ref".  This means that the type system can treat
3990                 // the type as it is expected, but when we generate the code, we generate
3991                 // the alternate kind of code.
3992                 //
3993                 public override Expression DoResolve (EmitContext ec)
3994                 {
3995                         DoResolveBase (ec);
3996
3997                         if (is_out && ec.DoFlowAnalysis && !IsAssigned (ec, loc))
3998                                 return null;
3999
4000                         if (ec.RemapToProxy)
4001                                 return ec.RemapParameter (idx);
4002
4003                         return this;
4004                 }
4005
4006                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
4007                 {
4008                         DoResolveBase (ec);
4009
4010                         SetAssigned (ec);
4011
4012                         if (ec.RemapToProxy)
4013                                 return ec.RemapParameterLValue (idx, right_side);
4014
4015                         return this;
4016                 }
4017
4018                 static public void EmitLdArg (ILGenerator ig, int x)
4019                 {
4020                         if (x <= 255){
4021                                 switch (x){
4022                                 case 0: ig.Emit (OpCodes.Ldarg_0); break;
4023                                 case 1: ig.Emit (OpCodes.Ldarg_1); break;
4024                                 case 2: ig.Emit (OpCodes.Ldarg_2); break;
4025                                 case 3: ig.Emit (OpCodes.Ldarg_3); break;
4026                                 default: ig.Emit (OpCodes.Ldarg_S, (byte) x); break;
4027                                 }
4028                         } else
4029                                 ig.Emit (OpCodes.Ldarg, x);
4030                 }
4031
4032                 //
4033                 // This method is used by parameters that are references, that are
4034                 // being passed as references:  we only want to pass the pointer (that
4035                 // is already stored in the parameter, not the address of the pointer,
4036                 // and not the value of the variable).
4037                 //
4038                 public void EmitLoad (EmitContext ec)
4039                 {
4040                         ILGenerator ig = ec.ig;
4041                         int arg_idx = idx;
4042
4043                         if (!ec.MethodIsStatic)
4044                                 arg_idx++;
4045
4046
4047                         EmitLdArg (ig, arg_idx);
4048
4049                         //
4050                         // FIXME: Review for anonymous methods
4051                         //
4052                 }
4053
4054                 public override void Emit (EmitContext ec)
4055                 {
4056                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4057                                 ec.EmitParameter (name);
4058                                 return;
4059                         }
4060
4061                         Emit (ec, false);
4062                 }
4063
4064                 public void Emit (EmitContext ec, bool leave_copy)
4065                 {
4066                         ILGenerator ig = ec.ig;
4067                         int arg_idx = idx;
4068
4069                         if (!ec.MethodIsStatic)
4070                                 arg_idx++;
4071
4072                         EmitLdArg (ig, arg_idx);
4073
4074                         if (is_ref) {
4075                                 if (prepared)
4076                                         ec.ig.Emit (OpCodes.Dup);
4077
4078                                 //
4079                                 // If we are a reference, we loaded on the stack a pointer
4080                                 // Now lets load the real value
4081                                 //
4082                                 LoadFromPtr (ig, type);
4083                         }
4084
4085                         if (leave_copy) {
4086                                 ec.ig.Emit (OpCodes.Dup);
4087
4088                                 if (is_ref) {
4089                                         temp = new LocalTemporary (ec, type);
4090                                         temp.Store (ec);
4091                                 }
4092                         }
4093                 }
4094
4095                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
4096                 {
4097                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4098                                 ec.EmitAssignParameter (name, source, leave_copy, prepare_for_load);
4099                                 return;
4100                         }
4101
4102                         ILGenerator ig = ec.ig;
4103                         int arg_idx = idx;
4104
4105                         prepared = prepare_for_load;
4106
4107                         if (!ec.MethodIsStatic)
4108                                 arg_idx++;
4109
4110                         if (is_ref && !prepared)
4111                                 EmitLdArg (ig, arg_idx);
4112
4113                         source.Emit (ec);
4114
4115                         if (leave_copy)
4116                                 ec.ig.Emit (OpCodes.Dup);
4117
4118                         if (is_ref) {
4119                                 if (leave_copy) {
4120                                         temp = new LocalTemporary (ec, type);
4121                                         temp.Store (ec);
4122                                 }
4123
4124                                 StoreFromPtr (ig, type);
4125
4126                                 if (temp != null)
4127                                         temp.Emit (ec);
4128                         } else {
4129                                 if (arg_idx <= 255)
4130                                         ig.Emit (OpCodes.Starg_S, (byte) arg_idx);
4131                                 else
4132                                         ig.Emit (OpCodes.Starg, arg_idx);
4133                         }
4134                 }
4135
4136                 public void AddressOf (EmitContext ec, AddressOp mode)
4137                 {
4138                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4139                                 ec.EmitAddressOfParameter (name);
4140                                 return;
4141                         }
4142
4143                         int arg_idx = idx;
4144
4145                         if (!ec.MethodIsStatic)
4146                                 arg_idx++;
4147
4148                         if (is_ref){
4149                                 if (arg_idx <= 255)
4150                                         ec.ig.Emit (OpCodes.Ldarg_S, (byte) arg_idx);
4151                                 else
4152                                         ec.ig.Emit (OpCodes.Ldarg, arg_idx);
4153                         } else {
4154                                 if (arg_idx <= 255)
4155                                         ec.ig.Emit (OpCodes.Ldarga_S, (byte) arg_idx);
4156                                 else
4157                                         ec.ig.Emit (OpCodes.Ldarga, arg_idx);
4158                         }
4159                 }
4160
4161         }
4162
4163         /// <summary>
4164         ///   Used for arguments to New(), Invocation()
4165         /// </summary>
4166         public class Argument {
4167                 public enum AType : byte {
4168                         Expression,
4169                         Ref,
4170                         Out,
4171                         ArgList
4172                 };
4173
4174                 public readonly AType ArgType;
4175                 public Expression Expr;
4176
4177                 public Argument (Expression expr, AType type)
4178                 {
4179                         this.Expr = expr;
4180                         this.ArgType = type;
4181                 }
4182
4183                 public Argument (Expression expr)
4184                 {
4185                         this.Expr = expr;
4186                         this.ArgType = AType.Expression;
4187                 }
4188
4189                 public Type Type {
4190                         get {
4191                                 if (ArgType == AType.Ref || ArgType == AType.Out)
4192                                         return TypeManager.GetReferenceType (Expr.Type);
4193                                 else
4194                                         return Expr.Type;
4195                         }
4196                 }
4197
4198                 public Parameter.Modifier GetParameterModifier ()
4199                 {
4200                         switch (ArgType) {
4201                         case AType.Out:
4202                                 return Parameter.Modifier.OUT | Parameter.Modifier.ISBYREF;
4203
4204                         case AType.Ref:
4205                                 return Parameter.Modifier.REF | Parameter.Modifier.ISBYREF;
4206
4207                         default:
4208                                 return Parameter.Modifier.NONE;
4209                         }
4210                 }
4211
4212                 public static string FullDesc (Argument a)
4213                 {
4214                         if (a.ArgType == AType.ArgList)
4215                                 return "__arglist";
4216
4217                         return (a.ArgType == AType.Ref ? "ref " :
4218                                 (a.ArgType == AType.Out ? "out " : "")) +
4219                                 TypeManager.CSharpName (a.Expr.Type);
4220                 }
4221
4222                 public bool ResolveMethodGroup (EmitContext ec, Location loc)
4223                 {
4224                         SimpleName sn = Expr as SimpleName;
4225                         if (sn != null)
4226                                 Expr = sn.GetMethodGroup ();
4227
4228                         // FIXME: csc doesn't report any error if you try to use `ref' or
4229                         //        `out' in a delegate creation expression.
4230                         Expr = Expr.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
4231                         if (Expr == null)
4232                                 return false;
4233
4234                         return true;
4235                 }
4236
4237                 void Error_LValueRequired (Location loc)
4238                 {
4239                         Report.Error (1510, loc, "An lvalue is required as an argument to out or ref");
4240                 }
4241
4242                 public bool Resolve (EmitContext ec, Location loc)
4243                 {
4244                         if (ArgType == AType.Ref) {
4245                                 ec.InRefOutArgumentResolving = true;
4246                                 Expr = Expr.Resolve (ec);
4247                                 ec.InRefOutArgumentResolving = false;
4248                                 if (Expr == null)
4249                                         return false;
4250
4251                                 Expr = Expr.DoResolveLValue (ec, Expr);
4252                                 if (Expr == null)
4253                                         Error_LValueRequired (loc);
4254                         } else if (ArgType == AType.Out) {
4255                                 ec.InRefOutArgumentResolving = true;
4256                                 Expr = Expr.DoResolveLValue (ec, EmptyExpression.Null);
4257                                 ec.InRefOutArgumentResolving = false;
4258
4259                                 if (Expr == null)
4260                                         Error_LValueRequired (loc);
4261                         }
4262                         else
4263                                 Expr = Expr.Resolve (ec);
4264
4265                         if (Expr == null)
4266                                 return false;
4267
4268                         if (ArgType == AType.Expression)
4269                                 return true;
4270                         else {
4271                                 //
4272                                 // Catch errors where fields of a MarshalByRefObject are passed as ref or out
4273                                 // This is only allowed for `this'
4274                                 //
4275                                 FieldExpr fe = Expr as FieldExpr;
4276                                 if (fe != null && !fe.IsStatic){
4277                                         Expression instance = fe.InstanceExpression;
4278
4279                                         if (instance.GetType () != typeof (This)){
4280                                                 if (fe.InstanceExpression.Type.IsSubclassOf (TypeManager.mbr_type)){
4281                                                         Report.SymbolRelatedToPreviousError (fe.InstanceExpression.Type);
4282                                                         Report.Error (197, loc, "Cannot pass '{0}' as ref or out or take its address because it is a member of a marshal-by-reference class",
4283                                                                 fe.Name);
4284                                                         return false;
4285                                                 }
4286                                         }
4287                                 }
4288                         }
4289
4290                         if (Expr.eclass != ExprClass.Variable){
4291                                 //
4292                                 // We just probe to match the CSC output
4293                                 //
4294                                 if (Expr.eclass == ExprClass.PropertyAccess ||
4295                                     Expr.eclass == ExprClass.IndexerAccess){
4296                                         Report.Error (
4297                                                 206, loc,
4298                                                 "A property or indexer can not be passed as an out or ref " +
4299                                                 "parameter");
4300                                 } else {
4301                                         Error_LValueRequired (loc);
4302                                 }
4303                                 return false;
4304                         }
4305
4306                         return true;
4307                 }
4308
4309                 public void Emit (EmitContext ec)
4310                 {
4311                         //
4312                         // Ref and Out parameters need to have their addresses taken.
4313                         //
4314                         // ParameterReferences might already be references, so we want
4315                         // to pass just the value
4316                         //
4317                         if (ArgType == AType.Ref || ArgType == AType.Out){
4318                                 AddressOp mode = AddressOp.Store;
4319
4320                                 if (ArgType == AType.Ref)
4321                                         mode |= AddressOp.Load;
4322
4323                                 if (Expr is ParameterReference){
4324                                         ParameterReference pr = (ParameterReference) Expr;
4325
4326                                         if (pr.IsRef)
4327                                                 pr.EmitLoad (ec);
4328                                         else {
4329
4330                                                 pr.AddressOf (ec, mode);
4331                                         }
4332                                 } else {
4333                                         if (Expr is IMemoryLocation)
4334                                                ((IMemoryLocation) Expr).AddressOf (ec, mode);
4335                                         else {
4336                                                 Report.Error (
4337                                                         1510, Expr.Location,
4338                                                         "An lvalue is required as an argument to out or ref");
4339                                                 return;
4340                                         }
4341                                 }
4342                         } else
4343                                 Expr.Emit (ec);
4344                 }
4345         }
4346
4347         /// <summary>
4348         ///   Invocation of methods or delegates.
4349         /// </summary>
4350         public class Invocation : ExpressionStatement {
4351                 public readonly ArrayList Arguments;
4352
4353                 Expression expr;
4354                 MethodBase method = null;
4355
4356                 //
4357                 // arguments is an ArrayList, but we do not want to typecast,
4358                 // as it might be null.
4359                 //
4360                 // FIXME: only allow expr to be a method invocation or a
4361                 // delegate invocation (7.5.5)
4362                 //
4363                 public Invocation (Expression expr, ArrayList arguments, Location l)
4364                 {
4365                         this.expr = expr;
4366                         Arguments = arguments;
4367                         loc = l;
4368                 }
4369
4370                 public Expression Expr {
4371                         get {
4372                                 return expr;
4373                         }
4374                 }
4375
4376                 /// <summary>
4377                 ///   Determines "better conversion" as specified in 7.4.2.3
4378                 ///
4379                 ///    Returns : p    if a->p is better,
4380                 ///              q    if a->q is better,
4381                 ///              null if neither is better
4382                 /// </summary>
4383                 static Type BetterConversion (EmitContext ec, Argument a, Type p, Type q, Location loc)
4384                 {
4385                         Type argument_type = TypeManager.TypeToCoreType (a.Type);
4386                         Expression argument_expr = a.Expr;
4387
4388                         // p = TypeManager.TypeToCoreType (p);
4389                         // q = TypeManager.TypeToCoreType (q);
4390
4391                         if (argument_type == null)
4392                                 throw new Exception ("Expression of type " + a.Expr +
4393                                                      " does not resolve its type");
4394
4395                         if (p == null || q == null)
4396                                 throw new InternalErrorException ("BetterConversion Got a null conversion");
4397
4398                         if (p == q)
4399                                 return null;
4400
4401                         if (argument_expr is NullLiteral) {
4402                         //
4403                                 // If the argument is null and one of the types to compare is 'object' and
4404                                 // the other is a reference type, we prefer the other.
4405                         //
4406                                 // This follows from the usual rules:
4407                                 //   * There is an implicit conversion from 'null' to type 'object'
4408                                 //   * There is an implicit conversion from 'null' to any reference type
4409                                 //   * There is an implicit conversion from any reference type to type 'object'
4410                                 //   * There is no implicit conversion from type 'object' to other reference types
4411                                 //  => Conversion of 'null' to a reference type is better than conversion to 'object'
4412                                 //
4413                                 //  FIXME: This probably isn't necessary, since the type of a NullLiteral is the
4414                                 //         null type. I think it used to be 'object' and thus needed a special
4415                                 //         case to avoid the immediately following two checks.
4416                                 //
4417                                 if (!p.IsValueType && q == TypeManager.object_type)
4418                                         return p;
4419                                 if (!q.IsValueType && p == TypeManager.object_type)
4420                                         return q;
4421                         }
4422
4423                         if (argument_type == p)
4424                                 return p;
4425
4426                         if (argument_type == q)
4427                                 return q;
4428
4429                         Expression p_tmp = new EmptyExpression (p);
4430                         Expression q_tmp = new EmptyExpression (q);
4431
4432                         bool p_to_q = Convert.ImplicitConversionExists (ec, p_tmp, q);
4433                         bool q_to_p = Convert.ImplicitConversionExists (ec, q_tmp, p);
4434
4435                         if (p_to_q && !q_to_p)
4436                                 return p;
4437
4438                         if (q_to_p && !p_to_q)
4439                                 return q;
4440
4441                         if (p == TypeManager.sbyte_type)
4442                                 if (q == TypeManager.byte_type || q == TypeManager.ushort_type ||
4443                                     q == TypeManager.uint32_type || q == TypeManager.uint64_type)
4444                                         return p;
4445                         if (q == TypeManager.sbyte_type)
4446                                 if (p == TypeManager.byte_type || p == TypeManager.ushort_type ||
4447                                     p == TypeManager.uint32_type || p == TypeManager.uint64_type)
4448                                         return q;
4449
4450                         if (p == TypeManager.short_type)
4451                                 if (q == TypeManager.ushort_type || q == TypeManager.uint32_type ||
4452                                     q == TypeManager.uint64_type)
4453                                         return p;
4454
4455                         if (q == TypeManager.short_type)
4456                                 if (p == TypeManager.ushort_type || p == TypeManager.uint32_type ||
4457                                     p == TypeManager.uint64_type)
4458                                         return q;
4459
4460                         if (p == TypeManager.int32_type)
4461                                 if (q == TypeManager.uint32_type || q == TypeManager.uint64_type)
4462                                         return p;
4463
4464                         if (q == TypeManager.int32_type)
4465                                 if (p == TypeManager.uint32_type || p == TypeManager.uint64_type)
4466                                         return q;
4467
4468                         if (p == TypeManager.int64_type)
4469                                 if (q == TypeManager.uint64_type)
4470                                         return p;
4471                         if (q == TypeManager.int64_type)
4472                                 if (p == TypeManager.uint64_type)
4473                                         return q;
4474
4475                         return null;
4476                 }
4477
4478                 /// <summary>
4479                 ///   Determines "Better function" between candidate
4480                 ///   and the current best match
4481                 /// </summary>
4482                 /// <remarks>
4483                 ///    Returns a boolean indicating :
4484                 ///     false if candidate ain't better
4485                 ///     true  if candidate is better than the current best match
4486                 /// </remarks>
4487                 static bool BetterFunction (EmitContext ec, ArrayList args, int argument_count,
4488                                            MethodBase candidate, bool candidate_params,
4489                                            MethodBase best, bool best_params, Location loc)
4490                 {
4491                         ParameterData candidate_pd = TypeManager.GetParameterData (candidate);
4492                         ParameterData best_pd = TypeManager.GetParameterData (best);
4493
4494                         bool better_at_least_one = false;
4495                         bool same = true;
4496                         for (int j = 0; j < argument_count; ++j) {
4497                                 Argument a = (Argument) args [j];
4498
4499                                 Type ct = TypeManager.TypeToCoreType (candidate_pd.ParameterType (j));
4500                                 Type bt = TypeManager.TypeToCoreType (best_pd.ParameterType (j));
4501
4502                                 if (candidate_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
4503                                         if (candidate_params)
4504                                                 ct = TypeManager.GetElementType (ct);
4505
4506                                 if (best_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
4507                                         if (best_params)
4508                                                 bt = TypeManager.GetElementType (bt);
4509
4510                                 if (ct.Equals (bt))
4511                                         continue;
4512
4513                                 same = false;
4514                                 Type better = BetterConversion (ec, a, ct, bt, loc);
4515                                 // for each argument, the conversion to 'ct' should be no worse than
4516                                 // the conversion to 'bt'.
4517                                 if (better == bt)
4518                                         return false;
4519
4520                                 // for at least one argument, the conversion to 'ct' should be better than
4521                                 // the conversion to 'bt'.
4522                                 if (better == ct)
4523                                         better_at_least_one = true;
4524                         }
4525
4526                         if (better_at_least_one)
4527                                 return true;
4528
4529                         if (!same)
4530                                 return false;
4531
4532                         //
4533                         // If two methods have equal parameter types, but
4534                         // only one of them is generic, the non-generic one wins.
4535                         //
4536                         if (TypeManager.IsGenericMethod (best) && !TypeManager.IsGenericMethod (candidate))
4537                                 return true;
4538                         else if (!TypeManager.IsGenericMethod (best) && TypeManager.IsGenericMethod (candidate))
4539                                 return false;
4540
4541                         //
4542                         // Note that this is not just an optimization.  This handles the case
4543                         // This handles the case
4544                         //
4545                         //   Add (float f1, float f2, float f3);
4546                         //   Add (params decimal [] foo);
4547                         //
4548                         // The call Add (3, 4, 5) should be ambiguous.  Without this check, the
4549                         // first candidate would've chosen as better.
4550                         //
4551                         //
4552                         // This handles the following cases:
4553                         //
4554                         //   Trim () is better than Trim (params char[] chars)
4555                         //   Concat (string s1, string s2, string s3) is better than
4556                         //     Concat (string s1, params string [] srest)
4557                         //
4558                         return !candidate_params && best_params;
4559                 }
4560
4561                 static bool IsOverride (MethodBase cand_method, MethodBase base_method)
4562                 {
4563                         if (!IsAncestralType (base_method.DeclaringType, cand_method.DeclaringType))
4564                                 return false;
4565
4566                         ParameterData cand_pd = TypeManager.GetParameterData (cand_method);
4567                         ParameterData base_pd = TypeManager.GetParameterData (base_method);
4568
4569                         if (cand_pd.Count != base_pd.Count)
4570                                 return false;
4571
4572                         for (int j = 0; j < cand_pd.Count; ++j) {
4573                                 Parameter.Modifier cm = cand_pd.ParameterModifier (j);
4574                                 Parameter.Modifier bm = base_pd.ParameterModifier (j);
4575                                 Type ct = TypeManager.TypeToCoreType (cand_pd.ParameterType (j));
4576                                 Type bt = TypeManager.TypeToCoreType (base_pd.ParameterType (j));
4577
4578                                 if (cm != bm || ct != bt)
4579                                         return false;
4580                         }
4581
4582                         return true;
4583                 }
4584
4585                 public static string FullMethodDesc (MethodBase mb)
4586                 {
4587                         string ret_type = "";
4588
4589                         if (mb == null)
4590                                 return "";
4591
4592                         if (mb is MethodInfo)
4593                                 ret_type = TypeManager.CSharpName (((MethodInfo) mb).ReturnType);
4594
4595                         StringBuilder sb = new StringBuilder (ret_type);
4596                         sb.Append (" ");
4597                         sb.Append (mb.ReflectedType.ToString ());
4598                         sb.Append (".");
4599                         sb.Append (mb.Name);
4600
4601                         ParameterData pd = TypeManager.GetParameterData (mb);
4602
4603                         int count = pd.Count;
4604                         sb.Append (" (");
4605
4606                         for (int i = count; i > 0; ) {
4607                                 i--;
4608
4609                                 sb.Append (pd.ParameterDesc (count - i - 1));
4610                                 if (i != 0)
4611                                         sb.Append (", ");
4612                         }
4613
4614                         sb.Append (")");
4615                         return sb.ToString ();
4616                 }
4617
4618                 public static MethodGroupExpr MakeUnionSet (Expression mg1, Expression mg2, Location loc)
4619                 {
4620                         MemberInfo [] miset;
4621                         MethodGroupExpr union;
4622
4623                         if (mg1 == null) {
4624                                 if (mg2 == null)
4625                                         return null;
4626                                 return (MethodGroupExpr) mg2;
4627                         } else {
4628                                 if (mg2 == null)
4629                                         return (MethodGroupExpr) mg1;
4630                         }
4631
4632                         MethodGroupExpr left_set = null, right_set = null;
4633                         int length1 = 0, length2 = 0;
4634
4635                         left_set = (MethodGroupExpr) mg1;
4636                         length1 = left_set.Methods.Length;
4637
4638                         right_set = (MethodGroupExpr) mg2;
4639                         length2 = right_set.Methods.Length;
4640
4641                         ArrayList common = new ArrayList ();
4642
4643                         foreach (MethodBase r in right_set.Methods){
4644                                 if (TypeManager.ArrayContainsMethod (left_set.Methods, r))
4645                                         common.Add (r);
4646                         }
4647
4648                         miset = new MemberInfo [length1 + length2 - common.Count];
4649                         left_set.Methods.CopyTo (miset, 0);
4650
4651                         int k = length1;
4652
4653                         foreach (MethodBase r in right_set.Methods) {
4654                                 if (!common.Contains (r))
4655                                         miset [k++] = r;
4656                         }
4657
4658                         union = new MethodGroupExpr (miset, loc);
4659
4660                         return union;
4661                 }
4662
4663                 public static bool IsParamsMethodApplicable (EmitContext ec, MethodGroupExpr me,
4664                                                              ArrayList arguments, int arg_count,
4665                                                              ref MethodBase candidate)
4666                 {
4667                         return IsParamsMethodApplicable (
4668                                 ec, me, arguments, arg_count, false, ref candidate) ||
4669                                 IsParamsMethodApplicable (
4670                                         ec, me, arguments, arg_count, true, ref candidate);
4671
4672
4673                 }
4674
4675                 static bool IsParamsMethodApplicable (EmitContext ec, MethodGroupExpr me,
4676                                                       ArrayList arguments, int arg_count,
4677                                                       bool do_varargs, ref MethodBase candidate)
4678                 {
4679                         if (!me.HasTypeArguments &&
4680                             !TypeManager.InferParamsTypeArguments (ec, arguments, ref candidate))
4681                                 return false;
4682
4683                         return IsParamsMethodApplicable (
4684                                 ec, arguments, arg_count, candidate, do_varargs);
4685                 }
4686
4687                 /// <summary>
4688                 ///   Determines if the candidate method, if a params method, is applicable
4689                 ///   in its expanded form to the given set of arguments
4690                 /// </summary>
4691                 static bool IsParamsMethodApplicable (EmitContext ec, ArrayList arguments,
4692                                                       int arg_count, MethodBase candidate,
4693                                                       bool do_varargs)
4694                 {
4695                         ParameterData pd = TypeManager.GetParameterData (candidate);
4696
4697                         int pd_count = pd.Count;
4698
4699                         if (pd_count == 0)
4700                                 return false;
4701
4702                         int count = pd_count - 1;
4703                         if (do_varargs) {
4704                                 if (pd.ParameterModifier (count) != Parameter.Modifier.ARGLIST)
4705                                         return false;
4706                                 if (pd_count != arg_count)
4707                                         return false;
4708                         } else {
4709                                 if (pd.ParameterModifier (count) != Parameter.Modifier.PARAMS)
4710                                 return false;
4711                         }
4712
4713                         if (count > arg_count)
4714                                 return false;
4715
4716                         if (pd_count == 1 && arg_count == 0)
4717                                 return true;
4718
4719                         //
4720                         // If we have come this far, the case which
4721                         // remains is when the number of parameters is
4722                         // less than or equal to the argument count.
4723                         //
4724                         for (int i = 0; i < count; ++i) {
4725
4726                                 Argument a = (Argument) arguments [i];
4727
4728                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
4729                                         (unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF)));
4730                                 Parameter.Modifier p_mod = pd.ParameterModifier (i) &
4731                                         (unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF)));
4732
4733                                 if (a_mod == p_mod) {
4734
4735                                         if (a_mod == Parameter.Modifier.NONE)
4736                                                 if (!Convert.ImplicitConversionExists (ec,
4737                                                                                        a.Expr,
4738                                                                                        pd.ParameterType (i)))
4739                                                         return false;
4740
4741                                         if ((a_mod & Parameter.Modifier.ISBYREF) != 0) {
4742                                                 Type pt = pd.ParameterType (i);
4743
4744                                                 if (!pt.IsByRef)
4745                                                         pt = TypeManager.GetReferenceType (pt);
4746
4747                                                 if (pt != a.Type)
4748                                                         return false;
4749                                         }
4750                                 } else
4751                                         return false;
4752
4753                         }
4754
4755                         if (do_varargs) {
4756                                 Argument a = (Argument) arguments [count];
4757                                 if (!(a.Expr is Arglist))
4758                                         return false;
4759
4760                                 return true;
4761                         }
4762
4763                         Type element_type = TypeManager.GetElementType (pd.ParameterType (pd_count - 1));
4764
4765                         for (int i = pd_count - 1; i < arg_count; i++) {
4766                                 Argument a = (Argument) arguments [i];
4767
4768                                 if (!Convert.ImplicitConversionExists (ec, a.Expr, element_type))
4769                                         return false;
4770                         }
4771
4772                         return true;
4773                 }
4774
4775                 public static bool IsApplicable (EmitContext ec, MethodGroupExpr me,
4776                                                  ArrayList arguments, int arg_count,
4777                                                  ref MethodBase candidate)
4778                 {
4779                         if (!me.HasTypeArguments &&
4780                             !TypeManager.InferTypeArguments (ec, arguments, ref candidate))
4781                                 return false;
4782
4783                         return IsApplicable (ec, arguments, arg_count, candidate);
4784                 }
4785
4786                 /// <summary>
4787                 ///   Determines if the candidate method is applicable (section 14.4.2.1)
4788                 ///   to the given set of arguments
4789                 /// </summary>
4790                 static bool IsApplicable (EmitContext ec, ArrayList arguments, int arg_count,
4791                                           MethodBase candidate)
4792                 {
4793                         ParameterData pd = TypeManager.GetParameterData (candidate);
4794
4795                         if (arg_count != pd.Count)
4796                                 return false;
4797
4798                         for (int i = arg_count; i > 0; ) {
4799                                 i--;
4800
4801                                 Argument a = (Argument) arguments [i];
4802
4803                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
4804                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
4805                                 Parameter.Modifier p_mod = pd.ParameterModifier (i) &
4806                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
4807
4808
4809                                 if (a_mod == p_mod ||
4810                                     (a_mod == Parameter.Modifier.NONE && p_mod == Parameter.Modifier.PARAMS)) {
4811                                         if (a_mod == Parameter.Modifier.NONE) {
4812                                                 if (!Convert.ImplicitConversionExists (ec,
4813                                                                                        a.Expr,
4814                                                                                        pd.ParameterType (i)))
4815                                                         return false;
4816                                         }
4817
4818                                         if ((a_mod & Parameter.Modifier.ISBYREF) != 0) {
4819                                                 Type pt = pd.ParameterType (i);
4820
4821                                                 if (!pt.IsByRef)
4822                                                         pt = TypeManager.GetReferenceType (pt);
4823
4824                                                 if (pt != a.Type)
4825                                                         return false;
4826                                         }
4827                                 } else
4828                                         return false;
4829                         }
4830
4831                         return true;
4832                 }
4833
4834                 static private bool IsAncestralType (Type first_type, Type second_type)
4835                 {
4836                         return first_type != second_type &&
4837                                 (second_type.IsSubclassOf (first_type) ||
4838                                  TypeManager.ImplementsInterface (second_type, first_type));
4839                 }
4840
4841                 /// <summary>
4842                 ///   Find the Applicable Function Members (7.4.2.1)
4843                 ///
4844                 ///   me: Method Group expression with the members to select.
4845                 ///       it might contain constructors or methods (or anything
4846                 ///       that maps to a method).
4847                 ///
4848                 ///   Arguments: ArrayList containing resolved Argument objects.
4849                 ///
4850                 ///   loc: The location if we want an error to be reported, or a Null
4851                 ///        location for "probing" purposes.
4852                 ///
4853                 ///   Returns: The MethodBase (either a ConstructorInfo or a MethodInfo)
4854                 ///            that is the best match of me on Arguments.
4855                 ///
4856                 /// </summary>
4857                 public static MethodBase OverloadResolve (EmitContext ec, MethodGroupExpr me,
4858                                                           ArrayList Arguments, bool may_fail,
4859                                                           Location loc)
4860                 {
4861                         MethodBase method = null;
4862                         bool method_params = false;
4863                         Type applicable_type = null;
4864                         int arg_count = 0;
4865                         ArrayList candidates = new ArrayList (2);
4866                         ArrayList candidate_overrides = null;
4867
4868                         //
4869                         // Used to keep a map between the candidate
4870                         // and whether it is being considered in its
4871                         // normal or expanded form
4872                         //
4873                         // false is normal form, true is expanded form
4874                         //
4875                         Hashtable candidate_to_form = null;
4876
4877                         if (Arguments != null)
4878                                 arg_count = Arguments.Count;
4879
4880                         if ((me.Name == "Invoke") &&
4881                             TypeManager.IsDelegateType (me.DeclaringType)) {
4882                                 Error_InvokeOnDelegate (loc);
4883                                 return null;
4884                         }
4885
4886                         MethodBase[] methods = me.Methods;
4887
4888                         //
4889                         // First we construct the set of applicable methods
4890                         //
4891                         bool is_sorted = true;
4892                         for (int i = 0; i < methods.Length; i++){
4893                                 Type decl_type = methods [i].DeclaringType;
4894
4895                                 //
4896                                 // If we have already found an applicable method
4897                                 // we eliminate all base types (Section 14.5.5.1)
4898                                 //
4899                                 if ((applicable_type != null) &&
4900                                     IsAncestralType (decl_type, applicable_type))
4901                                         continue;
4902
4903                                 //
4904                                 // Methods marked 'override' don't take part in 'applicable_type'
4905                                 // computation, nor in the actual overload resolution.
4906                                 // However, they still need to be emitted instead of a base virtual method.
4907                                 // We avoid doing the 'applicable' test here, since it'll anyway be applied
4908                                 // to the base virtual function, and IsOverride is much faster than IsApplicable.
4909                                 //
4910                                 if (!me.IsBase &&
4911                                     methods [i].IsVirtual &&
4912                                     (methods [i].Attributes & MethodAttributes.NewSlot) == 0) {
4913                                         if (candidate_overrides == null)
4914                                                 candidate_overrides = new ArrayList ();
4915                                         candidate_overrides.Add (methods [i]);
4916                                         continue;
4917                                 }
4918
4919                                 //
4920                                 // Check if candidate is applicable (section 14.4.2.1)
4921                                 //   Is candidate applicable in normal form?
4922                                 //
4923                                 bool is_applicable = IsApplicable (
4924                                         ec, me, Arguments, arg_count, ref methods [i]);
4925
4926                                 if (!is_applicable &&
4927                                     (IsParamsMethodApplicable (
4928                                             ec, me, Arguments, arg_count, ref methods [i]))) {
4929                                         MethodBase candidate = methods [i];
4930                                         if (candidate_to_form == null)
4931                                                 candidate_to_form = new PtrHashtable ();
4932                                         candidate_to_form [candidate] = candidate;
4933                                         // Candidate is applicable in expanded form
4934                                         is_applicable = true;
4935                                 }
4936
4937                                 if (!is_applicable)
4938                                         continue;
4939
4940                                 candidates.Add (methods [i]);
4941
4942                                 if (applicable_type == null)
4943                                         applicable_type = decl_type;
4944                                 else if (applicable_type != decl_type) {
4945                                         is_sorted = false;
4946                                         if (IsAncestralType (applicable_type, decl_type))
4947                                                 applicable_type = decl_type;
4948                                 }
4949                         }
4950
4951                         int candidate_top = candidates.Count;
4952
4953                         if (applicable_type == null) {
4954                                 //
4955                                 // Okay so we have failed to find anything so we
4956                                 // return by providing info about the closest match
4957                                 //
4958                                 for (int i = 0; i < methods.Length; ++i) {
4959                                         MethodBase c = (MethodBase) methods [i];
4960                                         ParameterData pd = TypeManager.GetParameterData (c);
4961
4962                                         if (pd.Count != arg_count)
4963                                                 continue;
4964
4965                                         if (!TypeManager.InferTypeArguments (ec, Arguments, ref c))
4966                                                 continue;
4967
4968                                         VerifyArgumentsCompat (ec, Arguments, arg_count,
4969                                                                c, false, null, may_fail, loc);
4970                                         break;
4971                                 }
4972
4973                                 if (!may_fail) {
4974                                         string report_name = me.Name;
4975                                         if (report_name == ".ctor")
4976                                                 report_name = me.DeclaringType.ToString ();
4977
4978                                         for (int i = 0; i < methods.Length; ++i) {
4979                                                 MethodBase c = methods [i];
4980                                                 ParameterData pd = TypeManager.GetParameterData (c);
4981
4982                                                 if (pd.Count != arg_count)
4983                                                         continue;
4984
4985                                                 if (TypeManager.InferTypeArguments (ec, Arguments, ref c))
4986                                                         continue;
4987
4988                                                 Report.Error (
4989                                                         411, loc, "The type arguments for " +
4990                                                         "method `{0}' cannot be infered from " +
4991                                                         "the usage. Try specifying the type " +
4992                                                         "arguments explicitly.", report_name);
4993                                                 return null;
4994                                         }
4995
4996                                         Error_WrongNumArguments (
4997                                                 loc, report_name, arg_count);
4998                                         return null;
4999                                 }
5000
5001                                 return null;
5002                         }
5003
5004                         if (!is_sorted) {
5005                                 //
5006                                 // At this point, applicable_type is _one_ of the most derived types
5007                                 // in the set of types containing the methods in this MethodGroup.
5008                                 // Filter the candidates so that they only contain methods from the
5009                                 // most derived types.
5010                                 //
5011
5012                                 int finalized = 0; // Number of finalized candidates
5013
5014                                 do {
5015                                         // Invariant: applicable_type is a most derived type
5016
5017                                         // We'll try to complete Section 14.5.5.1 for 'applicable_type' by
5018                                         // eliminating all it's base types.  At the same time, we'll also move
5019                                         // every unrelated type to the end of the array, and pick the next
5020                                         // 'applicable_type'.
5021
5022                                         Type next_applicable_type = null;
5023                                         int j = finalized; // where to put the next finalized candidate
5024                                         int k = finalized; // where to put the next undiscarded candidate
5025                                         for (int i = finalized; i < candidate_top; ++i) {
5026                                                 MethodBase candidate = (MethodBase) candidates [i];
5027                                                 Type decl_type = candidate.DeclaringType;
5028
5029                                                 if (decl_type == applicable_type) {
5030                                                         candidates [k++] = candidates [j];
5031                                                         candidates [j++] = candidates [i];
5032                                                         continue;
5033                                                 }
5034
5035                                                 if (IsAncestralType (decl_type, applicable_type))
5036                                                         continue;
5037
5038                                                 if (next_applicable_type != null &&
5039                                                     IsAncestralType (decl_type, next_applicable_type))
5040                                                         continue;
5041
5042                                                 candidates [k++] = candidates [i];
5043
5044                                                 if (next_applicable_type == null ||
5045                                                     IsAncestralType (next_applicable_type, decl_type))
5046                                                         next_applicable_type = decl_type;
5047                                         }
5048
5049                                         applicable_type = next_applicable_type;
5050                                         finalized = j;
5051                                         candidate_top = k;
5052                                 } while (applicable_type != null);
5053                         }
5054
5055                         //
5056                         // Now we actually find the best method
5057                         //
5058
5059                         method = (MethodBase) candidates [0];
5060                         method_params = candidate_to_form != null && candidate_to_form.Contains (method);
5061                         for (int ix = 1; ix < candidate_top; ix++){
5062                                 MethodBase candidate = (MethodBase) candidates [ix];
5063
5064                                 if (candidate == method)
5065                                         continue;
5066
5067                                 bool cand_params = candidate_to_form != null && candidate_to_form.Contains (candidate);
5068
5069                                 if (BetterFunction (ec, Arguments, arg_count,
5070                                                     candidate, cand_params,
5071                                                     method, method_params, loc)) {
5072                                         method = candidate;
5073                                         method_params = cand_params;
5074                                 }
5075                         }
5076
5077                         //
5078                         // Now check that there are no ambiguities i.e the selected method
5079                         // should be better than all the others
5080                         //
5081                         bool ambiguous = false;
5082                         for (int ix = 0; ix < candidate_top; ix++){
5083                                 MethodBase candidate = (MethodBase) candidates [ix];
5084
5085                                 if (candidate == method)
5086                                         continue;
5087
5088                                 bool cand_params = candidate_to_form != null && candidate_to_form.Contains (candidate);
5089                                 if (!BetterFunction (ec, Arguments, arg_count,
5090                                                     method, method_params,
5091                                                     candidate, cand_params,
5092                                                      loc)) {
5093                                         Report.SymbolRelatedToPreviousError (candidate);
5094                                         ambiguous = true;
5095                                 }
5096                         }
5097
5098                         if (ambiguous) {
5099                                 Report.SymbolRelatedToPreviousError (method);
5100                                 Report.Error (121, loc, "Ambiguous call when selecting function due to implicit casts");
5101                                 return null;
5102                         }
5103
5104                         //
5105                         // If the method is a virtual function, pick an override closer to the LHS type.
5106                         //
5107                         if (!me.IsBase && method.IsVirtual) {
5108                                 if ((method.Attributes & MethodAttributes.NewSlot) != MethodAttributes.NewSlot)
5109                                         throw new InternalErrorException (
5110                                                 "Should not happen.  An 'override' method took part in overload resolution: " + method);
5111
5112                                 if (candidate_overrides != null)
5113                                         foreach (MethodBase candidate in candidate_overrides) {
5114                                                 if (IsOverride (candidate, method))
5115                                                         method = candidate;
5116                                         }
5117                         }
5118
5119                         //
5120                         // And now check if the arguments are all
5121                         // compatible, perform conversions if
5122                         // necessary etc. and return if everything is
5123                         // all right
5124                         //
5125                         if (!VerifyArgumentsCompat (ec, Arguments, arg_count, method,
5126                                                     method_params, null, may_fail, loc))
5127                                 return null;
5128
5129                         if (method != null) {
5130                                 IMethodData data = TypeManager.GetMethod (method);
5131                                 if (data != null)
5132                                         data.SetMemberIsUsed ();
5133                         }
5134                         return method;
5135                 }
5136
5137                 static void Error_WrongNumArguments (Location loc, String name, int arg_count)
5138                 {
5139                         if (name == "Finalize" && arg_count == 0) {
5140                                 Report.Error (245, loc, "Destructors and object.Finalize cannot be called directly. Consider calling IDisposable.Dispose if available");
5141                         }
5142                         else {
5143                                 Report.Error (1501, loc,
5144                                         "No overload for method `" + name + "' takes `" +
5145                                         arg_count + "' arguments");
5146                         }
5147                 }
5148
5149                 static void Error_InvokeOnDelegate (Location loc)
5150                 {
5151                         Report.Error (1533, loc,
5152                                       "Invoke cannot be called directly on a delegate");
5153                 }
5154
5155                 static void Error_InvalidArguments (Location loc, int idx, MethodBase method,
5156                                                     Type delegate_type, string arg_sig, string par_desc)
5157                 {
5158                         if (delegate_type == null)
5159                                 Report.Error (1502, loc,
5160                                               "The best overloaded match for method '" +
5161                                               FullMethodDesc (method) +
5162                                               "' has some invalid arguments");
5163                         else
5164                                 Report.Error (1594, loc,
5165                                               "Delegate '" + delegate_type.ToString () +
5166                                               "' has some invalid arguments.");
5167                         Report.Error (1503, loc,
5168                                       String.Format ("Argument {0}: Cannot convert from '{1}' to '{2}'",
5169                                                      idx, arg_sig, par_desc));
5170                 }
5171
5172                 public static bool VerifyArgumentsCompat (EmitContext ec, ArrayList Arguments,
5173                                                           int arg_count, MethodBase method,
5174                                                           bool chose_params_expanded,
5175                                                           Type delegate_type, bool may_fail,
5176                                                           Location loc)
5177                 {
5178                         ParameterData pd = TypeManager.GetParameterData (method);
5179                         int pd_count = pd.Count;
5180
5181                         for (int j = 0; j < arg_count; j++) {
5182                                 Argument a = (Argument) Arguments [j];
5183                                 Expression a_expr = a.Expr;
5184                                 Type parameter_type = pd.ParameterType (j);
5185                                 Parameter.Modifier pm = pd.ParameterModifier (j);
5186
5187                                 if (pm == Parameter.Modifier.PARAMS){
5188                                         if ((pm & ~Parameter.Modifier.PARAMS) != a.GetParameterModifier ()) {
5189                                                 if (!may_fail)
5190                                                         Error_InvalidArguments (
5191                                                                 loc, j, method, delegate_type,
5192                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5193                                                 return false;
5194                                         }
5195
5196                                         if (chose_params_expanded)
5197                                                 parameter_type = TypeManager.GetElementType (parameter_type);
5198                                 } else if (pm == Parameter.Modifier.ARGLIST){
5199                                         continue;
5200                                 } else {
5201                                         //
5202                                         // Check modifiers
5203                                         //
5204                                         if (pd.ParameterModifier (j) != a.GetParameterModifier ()){
5205                                                 if (!may_fail)
5206                                                         Error_InvalidArguments (
5207                                                                 loc, j, method, delegate_type,
5208                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5209                                                 return false;
5210                                         }
5211                                 }
5212
5213                                 //
5214                                 // Check Type
5215                                 //
5216                                 if (!TypeManager.IsEqual (a.Type, parameter_type)){
5217                                         Expression conv;
5218
5219                                         conv = Convert.ImplicitConversion (ec, a_expr, parameter_type, loc);
5220
5221                                         if (conv == null) {
5222                                                 if (!may_fail)
5223                                                         Error_InvalidArguments (
5224                                                                 loc, j, method, delegate_type,
5225                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5226                                                 return false;
5227                                         }
5228
5229                                         //
5230                                         // Update the argument with the implicit conversion
5231                                         //
5232                                         if (a_expr != conv)
5233                                                 a.Expr = conv;
5234                                 }
5235
5236                                 if (parameter_type.IsPointer){
5237                                         if (!ec.InUnsafe){
5238                                                 UnsafeError (loc);
5239                                                 return false;
5240                                         }
5241                                 }
5242
5243                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
5244                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
5245                                 Parameter.Modifier p_mod = pd.ParameterModifier (j) &
5246                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
5247
5248                                 if (a_mod != p_mod &&
5249                                     pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS) {
5250                                         if (!may_fail) {
5251                                                 Report.Error (1502, loc,
5252                                                        "The best overloaded match for method '" + FullMethodDesc (method)+
5253                                                        "' has some invalid arguments");
5254                                                 Report.Error (1503, loc,
5255                                                        "Argument " + (j+1) +
5256                                                        ": Cannot convert from '" + Argument.FullDesc (a)
5257                                                        + "' to '" + pd.ParameterDesc (j) + "'");
5258                                         }
5259
5260                                         return false;
5261                                 }
5262                         }
5263
5264                         return true;
5265                 }
5266
5267                 public override Expression DoResolve (EmitContext ec)
5268                 {
5269                         //
5270                         // First, resolve the expression that is used to
5271                         // trigger the invocation
5272                         //
5273                         SimpleName sn = expr as SimpleName;
5274                         if (sn != null)
5275                                 expr = sn.GetMethodGroup ();
5276
5277                         expr = expr.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
5278                         if (expr == null)
5279                                 return null;
5280
5281                         if (!(expr is MethodGroupExpr)) {
5282                                 Type expr_type = expr.Type;
5283
5284                                 if (expr_type != null){
5285                                         bool IsDelegate = TypeManager.IsDelegateType (expr_type);
5286                                         if (IsDelegate)
5287                                                 return (new DelegateInvocation (
5288                                                         this.expr, Arguments, loc)).Resolve (ec);
5289                                 }
5290                         }
5291
5292                         if (!(expr is MethodGroupExpr)){
5293                                 expr.Error_UnexpectedKind (ResolveFlags.MethodGroup, loc);
5294                                 return null;
5295                         }
5296
5297                         //
5298                         // Next, evaluate all the expressions in the argument list
5299                         //
5300                         if (Arguments != null){
5301                                 foreach (Argument a in Arguments){
5302                                         if (!a.Resolve (ec, loc))
5303                                                 return null;
5304                                 }
5305                         }
5306
5307                         MethodGroupExpr mg = (MethodGroupExpr) expr;
5308                         method = OverloadResolve (ec, mg, Arguments, false, loc);
5309
5310                         if (method == null)
5311                                 return null;
5312
5313                         MethodInfo mi = method as MethodInfo;
5314                         if (mi != null) {
5315                                 type = TypeManager.TypeToCoreType (mi.ReturnType);
5316                                 Expression iexpr = mg.InstanceExpression;
5317                                 if (mi.IsStatic) {
5318                                         if (iexpr == null ||
5319                                             iexpr is This || iexpr is EmptyExpression ||
5320                                             mg.IdenticalTypeName) {
5321                                                 mg.InstanceExpression = null;
5322                                         } else {
5323                                                 MemberExpr.error176 (loc, mi.Name);
5324                                                 return null;
5325                                         }
5326                                 } else {
5327                                         if (iexpr == null || iexpr is EmptyExpression) {
5328                                                 SimpleName.Error_ObjectRefRequired (ec, loc, mi.Name);
5329                                                 return null;
5330                                         }
5331                                 }
5332                         }
5333
5334                         if (type.IsPointer){
5335                                 if (!ec.InUnsafe){
5336                                         UnsafeError (loc);
5337                                         return null;
5338                                 }
5339                         }
5340
5341                         //
5342                         // Only base will allow this invocation to happen.
5343                         //
5344                         if (mg.IsBase && method.IsAbstract){
5345                                 Report.Error (205, loc, "Cannot call an abstract base member: " +
5346                                               FullMethodDesc (method));
5347                                 return null;
5348                         }
5349
5350                         if (method.Name == "Finalize" && Arguments == null) {
5351                                 Report.Error (250, loc, "Do not directly call your base class Finalize method. It is called automatically from your destructor");
5352                                 return null;
5353                         }
5354
5355                         if ((method.Attributes & MethodAttributes.SpecialName) != 0){
5356                                 if (TypeManager.LookupDeclSpace (method.DeclaringType) != null || TypeManager.IsSpecialMethod (method)) {
5357                                         Report.Error (571, loc, TypeManager.CSharpSignature (method) + ": can not call operator or accessor");
5358                                         return null;
5359                                 }
5360                         }
5361
5362                         if (mg.InstanceExpression != null)
5363                                 mg.InstanceExpression.CheckMarshallByRefAccess (ec.ContainerType);
5364
5365                         eclass = ExprClass.Value;
5366                         return this;
5367                 }
5368
5369                 // <summary>
5370                 //   Emits the list of arguments as an array
5371                 // </summary>
5372                 static void EmitParams (EmitContext ec, int idx, ArrayList arguments)
5373                 {
5374                         ILGenerator ig = ec.ig;
5375                         int count = arguments.Count - idx;
5376                         Argument a = (Argument) arguments [idx];
5377                         Type t = a.Expr.Type;
5378
5379                         IntConstant.EmitInt (ig, count);
5380                         ig.Emit (OpCodes.Newarr, TypeManager.TypeToCoreType (t));
5381
5382                         int top = arguments.Count;
5383                         for (int j = idx; j < top; j++){
5384                                 a = (Argument) arguments [j];
5385
5386                                 ig.Emit (OpCodes.Dup);
5387                                 IntConstant.EmitInt (ig, j - idx);
5388
5389                                 bool is_stobj, has_type_arg;
5390                                 OpCode op = ArrayAccess.GetStoreOpcode (t, out is_stobj, out has_type_arg);
5391                                 if (is_stobj)
5392                                         ig.Emit (OpCodes.Ldelema, t);
5393
5394                                 a.Emit (ec);
5395
5396                                 if (has_type_arg)
5397                                         ig.Emit (op, t);
5398                                 else
5399                                         ig.Emit (op);
5400                         }
5401                 }
5402
5403                 /// <summary>
5404                 ///   Emits a list of resolved Arguments that are in the arguments
5405                 ///   ArrayList.
5406                 ///
5407                 ///   The MethodBase argument might be null if the
5408                 ///   emission of the arguments is known not to contain
5409                 ///   a `params' field (for example in constructors or other routines
5410                 ///   that keep their arguments in this structure)
5411                 ///
5412                 ///   if `dup_args' is true, a copy of the arguments will be left
5413                 ///   on the stack. If `dup_args' is true, you can specify `this_arg'
5414                 ///   which will be duplicated before any other args. Only EmitCall
5415                 ///   should be using this interface.
5416                 /// </summary>
5417                 public static void EmitArguments (EmitContext ec, MethodBase mb, ArrayList arguments, bool dup_args, LocalTemporary this_arg)
5418                 {
5419                         ParameterData pd;
5420                         if (mb != null)
5421                                 pd = TypeManager.GetParameterData (mb);
5422                         else
5423                                 pd = null;
5424
5425                         LocalTemporary [] temps = null;
5426
5427                         if (dup_args)
5428                                 temps = new LocalTemporary [arguments.Count];
5429
5430                         //
5431                         // If we are calling a params method with no arguments, special case it
5432                         //
5433                         if (arguments == null){
5434                                 if (pd != null && pd.Count > 0 &&
5435                                     pd.ParameterModifier (0) == Parameter.Modifier.PARAMS){
5436                                         ILGenerator ig = ec.ig;
5437
5438                                         IntConstant.EmitInt (ig, 0);
5439                                         ig.Emit (OpCodes.Newarr, TypeManager.GetElementType (pd.ParameterType (0)));
5440                                 }
5441
5442                                 return;
5443                         }
5444
5445                         int top = arguments.Count;
5446
5447                         for (int i = 0; i < top; i++){
5448                                 Argument a = (Argument) arguments [i];
5449
5450                                 if (pd != null){
5451                                         if (pd.ParameterModifier (i) == Parameter.Modifier.PARAMS){
5452                                                 //
5453                                                 // Special case if we are passing the same data as the
5454                                                 // params argument, do not put it in an array.
5455                                                 //
5456                                                 if (pd.ParameterType (i) == a.Type)
5457                                                         a.Emit (ec);
5458                                                 else
5459                                                         EmitParams (ec, i, arguments);
5460                                                 return;
5461                                         }
5462                                 }
5463
5464                                 a.Emit (ec);
5465                                 if (dup_args) {
5466                                         ec.ig.Emit (OpCodes.Dup);
5467                                         (temps [i] = new LocalTemporary (ec, a.Type)).Store (ec);
5468                                 }
5469                         }
5470
5471                         if (dup_args) {
5472                                 if (this_arg != null)
5473                                         this_arg.Emit (ec);
5474
5475                                 for (int i = 0; i < top; i ++)
5476                                         temps [i].Emit (ec);
5477                         }
5478
5479                         if (pd != null && pd.Count > top &&
5480                             pd.ParameterModifier (top) == Parameter.Modifier.PARAMS){
5481                                 ILGenerator ig = ec.ig;
5482
5483                                 IntConstant.EmitInt (ig, 0);
5484                                 ig.Emit (OpCodes.Newarr, TypeManager.GetElementType (pd.ParameterType (top)));
5485                         }
5486                 }
5487
5488                 static Type[] GetVarargsTypes (EmitContext ec, MethodBase mb,
5489                                                ArrayList arguments)
5490                 {
5491                         ParameterData pd = TypeManager.GetParameterData (mb);
5492
5493                         if (arguments == null)
5494                                 return new Type [0];
5495
5496                         Argument a = (Argument) arguments [pd.Count - 1];
5497                         Arglist list = (Arglist) a.Expr;
5498
5499                         return list.ArgumentTypes;
5500                 }
5501
5502                 /// <summary>
5503                 /// This checks the ConditionalAttribute on the method
5504                 /// </summary>
5505                 static bool IsMethodExcluded (MethodBase method, EmitContext ec)
5506                 {
5507                         if (method.IsConstructor)
5508                                 return false;
5509
5510                         IMethodData md = TypeManager.GetMethod (method);
5511                         if (md != null)
5512                                 return md.IsExcluded (ec);
5513
5514                         // For some methods (generated by delegate class) GetMethod returns null
5515                         // because they are not included in builder_to_method table
5516                         if (method.DeclaringType is TypeBuilder)
5517                                 return false;
5518
5519                         return AttributeTester.IsConditionalMethodExcluded (method);
5520                 }
5521
5522                 /// <remarks>
5523                 ///   is_base tells whether we want to force the use of the `call'
5524                 ///   opcode instead of using callvirt.  Call is required to call
5525                 ///   a specific method, while callvirt will always use the most
5526                 ///   recent method in the vtable.
5527                 ///
5528                 ///   is_static tells whether this is an invocation on a static method
5529                 ///
5530                 ///   instance_expr is an expression that represents the instance
5531                 ///   it must be non-null if is_static is false.
5532                 ///
5533                 ///   method is the method to invoke.
5534                 ///
5535                 ///   Arguments is the list of arguments to pass to the method or constructor.
5536                 /// </remarks>
5537                 public static void EmitCall (EmitContext ec, bool is_base,
5538                                              bool is_static, Expression instance_expr,
5539                                              MethodBase method, ArrayList Arguments, Location loc)
5540                 {
5541                         EmitCall (ec, is_base, is_static, instance_expr, method, Arguments, loc, false, false);
5542                 }
5543
5544                 // `dup_args' leaves an extra copy of the arguments on the stack
5545                 // `omit_args' does not leave any arguments at all.
5546                 // So, basically, you could make one call with `dup_args' set to true,
5547                 // and then another with `omit_args' set to true, and the two calls
5548                 // would have the same set of arguments. However, each argument would
5549                 // only have been evaluated once.
5550                 public static void EmitCall (EmitContext ec, bool is_base,
5551                                              bool is_static, Expression instance_expr,
5552                                              MethodBase method, ArrayList Arguments, Location loc,
5553                                              bool dup_args, bool omit_args)
5554                 {
5555                         ILGenerator ig = ec.ig;
5556                         bool struct_call = false;
5557                         bool this_call = false;
5558                         LocalTemporary this_arg = null;
5559
5560                         Type decl_type = method.DeclaringType;
5561
5562                         if (!RootContext.StdLib) {
5563                                 // Replace any calls to the system's System.Array type with calls to
5564                                 // the newly created one.
5565                                 if (method == TypeManager.system_int_array_get_length)
5566                                         method = TypeManager.int_array_get_length;
5567                                 else if (method == TypeManager.system_int_array_get_rank)
5568                                         method = TypeManager.int_array_get_rank;
5569                                 else if (method == TypeManager.system_object_array_clone)
5570                                         method = TypeManager.object_array_clone;
5571                                 else if (method == TypeManager.system_int_array_get_length_int)
5572                                         method = TypeManager.int_array_get_length_int;
5573                                 else if (method == TypeManager.system_int_array_get_lower_bound_int)
5574                                         method = TypeManager.int_array_get_lower_bound_int;
5575                                 else if (method == TypeManager.system_int_array_get_upper_bound_int)
5576                                         method = TypeManager.int_array_get_upper_bound_int;
5577                                 else if (method == TypeManager.system_void_array_copyto_array_int)
5578                                         method = TypeManager.void_array_copyto_array_int;
5579                         }
5580
5581                         if (ec.TestObsoleteMethodUsage) {
5582                                 //
5583                                 // This checks ObsoleteAttribute on the method and on the declaring type
5584                                 //
5585                                 ObsoleteAttribute oa = AttributeTester.GetMethodObsoleteAttribute (method);
5586                                 if (oa != null)
5587                                         AttributeTester.Report_ObsoleteMessage (oa, TypeManager.CSharpSignature (method), loc);
5588
5589                                 oa = AttributeTester.GetObsoleteAttribute (method.DeclaringType);
5590                                 if (oa != null) {
5591                                         AttributeTester.Report_ObsoleteMessage (oa, method.DeclaringType.FullName, loc);
5592                                 }
5593                         }
5594
5595                         if (IsMethodExcluded (method, ec))
5596                                 return;
5597
5598                         if (!is_static){
5599                                 this_call = instance_expr == null;
5600                                 if (decl_type.IsValueType || (!this_call && instance_expr.Type.IsValueType))
5601                                         struct_call = true;
5602
5603                                 //
5604                                 // If this is ourselves, push "this"
5605                                 //
5606                                 if (!omit_args) {
5607                                         Type t = null;
5608                                         if (this_call) {
5609                                                 ig.Emit (OpCodes.Ldarg_0);
5610                                                 t = decl_type;
5611                                         } else {
5612                                                 Type iexpr_type = instance_expr.Type;
5613
5614                                                 //
5615                                                 // Push the instance expression
5616                                                 //
5617                                                 if (TypeManager.IsValueType (iexpr_type)) {
5618                                                         //
5619                                                         // Special case: calls to a function declared in a
5620                                                         // reference-type with a value-type argument need
5621                                                         // to have their value boxed.
5622                                                         if (decl_type.IsValueType ||
5623                                                             iexpr_type.IsGenericParameter) {
5624                                                                 //
5625                                                                 // If the expression implements IMemoryLocation, then
5626                                                                 // we can optimize and use AddressOf on the
5627                                                                 // return.
5628                                                                 //
5629                                                                 // If not we have to use some temporary storage for
5630                                                                 // it.
5631                                                                 if (instance_expr is IMemoryLocation) {
5632                                                                         ((IMemoryLocation)instance_expr).
5633                                                                                 AddressOf (ec, AddressOp.LoadStore);
5634                                                                 } else {
5635                                                                         LocalTemporary temp = new LocalTemporary (ec, iexpr_type);
5636                                                                         instance_expr.Emit (ec);
5637                                                                         temp.Store (ec);
5638                                                                         temp.AddressOf (ec, AddressOp.Load);
5639                                                                 }
5640
5641                                                                 // avoid the overhead of doing this all the time.
5642                                                                 if (dup_args)
5643                                                                         t = TypeManager.GetReferenceType (iexpr_type);
5644                                                         } else {
5645                                                                 instance_expr.Emit (ec);
5646                                                                 ig.Emit (OpCodes.Box, instance_expr.Type);
5647                                                                 t = TypeManager.object_type;
5648                                                         }
5649                                                 } else {
5650                                                         instance_expr.Emit (ec);
5651                                                         t = instance_expr.Type;
5652                                                 }
5653                                         }
5654
5655                                         if (dup_args) {
5656                                                 this_arg = new LocalTemporary (ec, t);
5657                                                 ig.Emit (OpCodes.Dup);
5658                                                 this_arg.Store (ec);
5659                                         }
5660                                 }
5661                         }
5662
5663                         if (!omit_args)
5664                                 EmitArguments (ec, method, Arguments, dup_args, this_arg);
5665
5666                         if ((instance_expr != null) && (instance_expr.Type.IsGenericParameter))
5667                                 ig.Emit (OpCodes.Constrained, instance_expr.Type);
5668
5669                         OpCode call_op;
5670                         if (is_static || struct_call || is_base || (this_call && !method.IsVirtual))
5671                                 call_op = OpCodes.Call;
5672                         else
5673                                 call_op = OpCodes.Callvirt;
5674
5675                         if ((method.CallingConvention & CallingConventions.VarArgs) != 0) {
5676                                 Type[] varargs_types = GetVarargsTypes (ec, method, Arguments);
5677                                 ig.EmitCall (call_op, (MethodInfo) method, varargs_types);
5678                                 return;
5679                         }
5680
5681                         //
5682                         // If you have:
5683                         // this.DoFoo ();
5684                         // and DoFoo is not virtual, you can omit the callvirt,
5685                         // because you don't need the null checking behavior.
5686                         //
5687                         if (method is MethodInfo)
5688                                 ig.Emit (call_op, (MethodInfo) method);
5689                         else
5690                                 ig.Emit (call_op, (ConstructorInfo) method);
5691                 }
5692
5693                 public override void Emit (EmitContext ec)
5694                 {
5695                         MethodGroupExpr mg = (MethodGroupExpr) this.expr;
5696
5697                         EmitCall (ec, mg.IsBase, method.IsStatic, mg.InstanceExpression, method, Arguments, loc);
5698                 }
5699
5700                 public override void EmitStatement (EmitContext ec)
5701                 {
5702                         Emit (ec);
5703
5704                         //
5705                         // Pop the return value if there is one
5706                         //
5707                         if (method is MethodInfo){
5708                                 Type ret = ((MethodInfo)method).ReturnType;
5709                                 if (TypeManager.TypeToCoreType (ret) != TypeManager.void_type)
5710                                         ec.ig.Emit (OpCodes.Pop);
5711                         }
5712                 }
5713         }
5714
5715         public class InvocationOrCast : ExpressionStatement
5716         {
5717                 Expression expr;
5718                 Expression argument;
5719
5720                 public InvocationOrCast (Expression expr, Expression argument, Location loc)
5721                 {
5722                         this.expr = expr;
5723                         this.argument = argument;
5724                         this.loc = loc;
5725                 }
5726
5727                 public override Expression DoResolve (EmitContext ec)
5728                 {
5729                         //
5730                         // First try to resolve it as a cast.
5731                         //
5732                         TypeExpr te = expr.ResolveAsTypeStep (ec) as TypeExpr;
5733                         if ((te != null) && (te.eclass == ExprClass.Type)) {
5734                                 Cast cast = new Cast (te, argument, loc);
5735                                 return cast.Resolve (ec);
5736                         }
5737
5738                         //
5739                         // This can either be a type or a delegate invocation.
5740                         // Let's just resolve it and see what we'll get.
5741                         //
5742                         expr = expr.Resolve (ec, ResolveFlags.Type | ResolveFlags.VariableOrValue);
5743                         if (expr == null)
5744                                 return null;
5745
5746                         //
5747                         // Ok, so it's a Cast.
5748                         //
5749                         if (expr.eclass == ExprClass.Type) {
5750                                 Cast cast = new Cast (new TypeExpression (expr.Type, loc), argument, loc);
5751                                 return cast.Resolve (ec);
5752                         }
5753
5754                         //
5755                         // It's a delegate invocation.
5756                         //
5757                         if (!TypeManager.IsDelegateType (expr.Type)) {
5758                                 Error (149, "Method name expected");
5759                                 return null;
5760                         }
5761
5762                         ArrayList args = new ArrayList ();
5763                         args.Add (new Argument (argument, Argument.AType.Expression));
5764                         DelegateInvocation invocation = new DelegateInvocation (expr, args, loc);
5765                         return invocation.Resolve (ec);
5766                 }
5767
5768                 void error201 ()
5769                 {
5770                         Error (201, "Only assignment, call, increment, decrement and new object " +
5771                                "expressions can be used as a statement");
5772                 }
5773
5774                 public override ExpressionStatement ResolveStatement (EmitContext ec)
5775                 {
5776                         //
5777                         // First try to resolve it as a cast.
5778                         //
5779                         TypeExpr te = expr.ResolveAsTypeStep (ec) as TypeExpr;
5780                         if ((te != null) && (te.eclass == ExprClass.Type)) {
5781                                 error201 ();
5782                                 return null;
5783                         }
5784
5785                         //
5786                         // This can either be a type or a delegate invocation.
5787                         // Let's just resolve it and see what we'll get.
5788                         //
5789                         expr = expr.Resolve (ec, ResolveFlags.Type | ResolveFlags.VariableOrValue);
5790                         if ((expr == null) || (expr.eclass == ExprClass.Type)) {
5791                                 error201 ();
5792                                 return null;
5793                         }
5794
5795                         //
5796                         // It's a delegate invocation.
5797                         //
5798                         if (!TypeManager.IsDelegateType (expr.Type)) {
5799                                 Error (149, "Method name expected");
5800                                 return null;
5801                         }
5802
5803                         ArrayList args = new ArrayList ();
5804                         args.Add (new Argument (argument, Argument.AType.Expression));
5805                         DelegateInvocation invocation = new DelegateInvocation (expr, args, loc);
5806                         return invocation.ResolveStatement (ec);
5807                 }
5808
5809                 public override void Emit (EmitContext ec)
5810                 {
5811                         throw new Exception ("Cannot happen");
5812                 }
5813
5814                 public override void EmitStatement (EmitContext ec)
5815                 {
5816                         throw new Exception ("Cannot happen");
5817                 }
5818         }
5819
5820         //
5821         // This class is used to "disable" the code generation for the
5822         // temporary variable when initializing value types.
5823         //
5824         class EmptyAddressOf : EmptyExpression, IMemoryLocation {
5825                 public void AddressOf (EmitContext ec, AddressOp Mode)
5826                 {
5827                         // nothing
5828                 }
5829         }
5830
5831         /// <summary>
5832         ///    Implements the new expression
5833         /// </summary>
5834         public class New : ExpressionStatement, IMemoryLocation {
5835                 public readonly ArrayList Arguments;
5836
5837                 //
5838                 // During bootstrap, it contains the RequestedType,
5839                 // but if `type' is not null, it *might* contain a NewDelegate
5840                 // (because of field multi-initialization)
5841                 //
5842                 public Expression RequestedType;
5843
5844                 MethodBase method = null;
5845
5846                 //
5847                 // If set, the new expression is for a value_target, and
5848                 // we will not leave anything on the stack.
5849                 //
5850                 Expression value_target;
5851                 bool value_target_set = false;
5852                 bool is_type_parameter = false;
5853
5854                 public New (Expression requested_type, ArrayList arguments, Location l)
5855                 {
5856                         RequestedType = requested_type;
5857                         Arguments = arguments;
5858                         loc = l;
5859                 }
5860
5861                 public bool SetValueTypeVariable (Expression value)
5862                 {
5863                         value_target = value;
5864                         value_target_set = true;
5865                         if (!(value_target is IMemoryLocation)){
5866                                 Error_UnexpectedKind ("variable", loc);
5867                                 return false;
5868                         }
5869                         return true;
5870                 }
5871
5872                 //
5873                 // This function is used to disable the following code sequence for
5874                 // value type initialization:
5875                 //
5876                 // AddressOf (temporary)
5877                 // Construct/Init
5878                 // LoadTemporary
5879                 //
5880                 // Instead the provide will have provided us with the address on the
5881                 // stack to store the results.
5882                 //
5883                 static Expression MyEmptyExpression;
5884
5885                 public void DisableTemporaryValueType ()
5886                 {
5887                         if (MyEmptyExpression == null)
5888                                 MyEmptyExpression = new EmptyAddressOf ();
5889
5890                         //
5891                         // To enable this, look into:
5892                         // test-34 and test-89 and self bootstrapping.
5893                         //
5894                         // For instance, we can avoid a copy by using `newobj'
5895                         // instead of Call + Push-temp on value types.
5896 //                      value_target = MyEmptyExpression;
5897                 }
5898
5899
5900                 /// <summary>
5901                 /// Converts complex core type syntax like 'new int ()' to simple constant
5902                 /// </summary>
5903                 Expression Constantify (Type t)
5904                 {
5905                         if (t == TypeManager.int32_type)
5906                                 return new IntConstant (0);
5907                         if (t == TypeManager.uint32_type)
5908                                 return new UIntConstant (0);
5909                         if (t == TypeManager.int64_type)
5910                                 return new LongConstant (0);
5911                         if (t == TypeManager.uint64_type)
5912                                 return new ULongConstant (0);
5913                         if (t == TypeManager.float_type)
5914                                 return new FloatConstant (0);
5915                         if (t == TypeManager.double_type)
5916                                 return new DoubleConstant (0);
5917                         if (t == TypeManager.short_type)
5918                                 return new ShortConstant (0);
5919                         if (t == TypeManager.ushort_type)
5920                                 return new UShortConstant (0);
5921                         if (t == TypeManager.sbyte_type)
5922                                 return new SByteConstant (0);
5923                         if (t == TypeManager.byte_type)
5924                                 return new ByteConstant (0);
5925                         if (t == TypeManager.char_type)
5926                                 return new CharConstant ('\0');
5927                         if (t == TypeManager.bool_type)
5928                                 return new BoolConstant (false);
5929                         if (t == TypeManager.decimal_type)
5930                                 return new DecimalConstant (0);
5931
5932                         return null;
5933                 }
5934
5935                 public override Expression DoResolve (EmitContext ec)
5936                 {
5937                         //
5938                         // The New DoResolve might be called twice when initializing field
5939                         // expressions (see EmitFieldInitializers, the call to
5940                         // GetInitializerExpression will perform a resolve on the expression,
5941                         // and later the assign will trigger another resolution
5942                         //
5943                         // This leads to bugs (#37014)
5944                         //
5945                         if (type != null){
5946                                 if (RequestedType is NewDelegate)
5947                                         return RequestedType;
5948                                 return this;
5949                         }
5950
5951                         TypeExpr texpr = RequestedType.ResolveAsTypeTerminal (ec);
5952                         if (texpr == null)
5953                                 return null;
5954
5955                         if (Arguments == null) {
5956                                 Expression c = Constantify (type);
5957                                 if (c != null)
5958                                         return c;
5959                         }
5960
5961                         type = texpr.Type;
5962                         if (type == null)
5963                                 return null;
5964
5965                         CheckObsoleteAttribute (type);
5966
5967                         bool IsDelegate = TypeManager.IsDelegateType (type);
5968
5969                         if (IsDelegate){
5970                                 RequestedType = (new NewDelegate (type, Arguments, loc)).Resolve (ec);
5971                                 if (RequestedType != null)
5972                                         if (!(RequestedType is DelegateCreation))
5973                                                 throw new Exception ("NewDelegate.Resolve returned a non NewDelegate: " + RequestedType.GetType ());
5974                                 return RequestedType;
5975                         }
5976
5977                         if (type.IsGenericParameter) {
5978                                 if (!TypeManager.HasConstructorConstraint (type)) {
5979                                         Error (304, String.Format (
5980                                                        "Cannot create an instance of the " +
5981                                                        "variable type '{0}' because it " +
5982                                                        "doesn't have the new() constraint",
5983                                                        type));
5984                                         return null;
5985                                 }
5986
5987                                 if ((Arguments != null) && (Arguments.Count != 0)) {
5988                                         Error (417, String.Format (
5989                                                        "`{0}': cannot provide arguments " +
5990                                                        "when creating an instance of a " +
5991                                                        "variable type.", type));
5992                                         return null;
5993                                 }
5994
5995                                 is_type_parameter = true;
5996                                 eclass = ExprClass.Value;
5997                                 return this;
5998                         }
5999
6000                         if (type.IsInterface || type.IsAbstract){
6001                                 Error (144, "It is not possible to create instances of interfaces or abstract classes");
6002                                 return null;
6003                         }
6004
6005                         if (type.IsAbstract && type.IsSealed) {
6006                                 Report.Error (712, loc, "Cannot create an instance of the static class '{0}'", TypeManager.CSharpName (type));
6007                                 return null;
6008                         }
6009
6010                         bool is_struct = type.IsValueType;
6011                         eclass = ExprClass.Value;
6012
6013                         //
6014                         // SRE returns a match for .ctor () on structs (the object constructor),
6015                         // so we have to manually ignore it.
6016                         //
6017                         if (is_struct && Arguments == null)
6018                                 return this;
6019
6020                         Expression ml;
6021                         ml = MemberLookupFinal (ec, type, type, ".ctor",
6022                                                 // For member-lookup, treat 'new Foo (bar)' as call to 'foo.ctor (bar)', where 'foo' is of type 'Foo'.
6023                                                 MemberTypes.Constructor,
6024                                                 AllBindingFlags | BindingFlags.DeclaredOnly, loc);
6025
6026                         if (ml == null)
6027                                 return null;
6028
6029                         if (! (ml is MethodGroupExpr)){
6030                                 if (!is_struct){
6031                                         ml.Error_UnexpectedKind ("method group", loc);
6032                                         return null;
6033                                 }
6034                         }
6035
6036                         if (ml != null) {
6037                                 if (Arguments != null){
6038                                         foreach (Argument a in Arguments){
6039                                                 if (!a.Resolve (ec, loc))
6040                                                         return null;
6041                                         }
6042                                 }
6043
6044                                 method = Invocation.OverloadResolve (
6045                                         ec, (MethodGroupExpr) ml, Arguments, true, loc);
6046
6047                         }
6048
6049                         if (method == null) {
6050                                 if (almostMatchedMembers.Count != 0) {
6051                                         MemberLookupFailed (ec, type, type, ".ctor", null, true, loc);
6052                                         return null;
6053                                 }
6054
6055                                 if (!is_struct || Arguments.Count > 0) {
6056                                         Error (1501, String.Format (
6057                                             "New invocation: Can not find a constructor in `{0}' for this argument list",
6058                                             TypeManager.CSharpName (type)));
6059                                         return null;
6060                                 }
6061                         }
6062
6063                         return this;
6064                 }
6065
6066                 bool DoEmitTypeParameter (EmitContext ec)
6067                 {
6068                         ILGenerator ig = ec.ig;
6069
6070                         ig.Emit (OpCodes.Ldtoken, type);
6071                         ig.Emit (OpCodes.Call, TypeManager.system_type_get_type_from_handle);
6072                         ig.Emit (OpCodes.Call, TypeManager.activator_create_instance);
6073                         ig.Emit (OpCodes.Unbox_Any, type);
6074
6075                         return true;
6076                 }
6077
6078                 //
6079                 // This DoEmit can be invoked in two contexts:
6080                 //    * As a mechanism that will leave a value on the stack (new object)
6081                 //    * As one that wont (init struct)
6082                 //
6083                 // You can control whether a value is required on the stack by passing
6084                 // need_value_on_stack.  The code *might* leave a value on the stack
6085                 // so it must be popped manually
6086                 //
6087                 // If we are dealing with a ValueType, we have a few
6088                 // situations to deal with:
6089                 //
6090                 //    * The target is a ValueType, and we have been provided
6091                 //      the instance (this is easy, we are being assigned).
6092                 //
6093                 //    * The target of New is being passed as an argument,
6094                 //      to a boxing operation or a function that takes a
6095                 //      ValueType.
6096                 //
6097                 //      In this case, we need to create a temporary variable
6098                 //      that is the argument of New.
6099                 //
6100                 // Returns whether a value is left on the stack
6101                 //
6102                 bool DoEmit (EmitContext ec, bool need_value_on_stack)
6103                 {
6104                         bool is_value_type = TypeManager.IsValueType (type);
6105                         ILGenerator ig = ec.ig;
6106
6107                         if (is_value_type){
6108                                 IMemoryLocation ml;
6109
6110                                 // Allow DoEmit() to be called multiple times.
6111                                 // We need to create a new LocalTemporary each time since
6112                                 // you can't share LocalBuilders among ILGeneators.
6113                                 if (!value_target_set)
6114                                         value_target = new LocalTemporary (ec, type);
6115
6116                                 ml = (IMemoryLocation) value_target;
6117                                 ml.AddressOf (ec, AddressOp.Store);
6118                         }
6119
6120                         if (method != null)
6121                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
6122
6123                         if (is_value_type){
6124                                 if (method == null)
6125                                         ig.Emit (OpCodes.Initobj, type);
6126                                 else
6127                                         ig.Emit (OpCodes.Call, (ConstructorInfo) method);
6128                                 if (need_value_on_stack){
6129                                         value_target.Emit (ec);
6130                                         return true;
6131                                 }
6132                                 return false;
6133                         } else {
6134                                 ig.Emit (OpCodes.Newobj, (ConstructorInfo) method);
6135                                 return true;
6136                         }
6137                 }
6138
6139                 public override void Emit (EmitContext ec)
6140                 {
6141                         if (is_type_parameter)
6142                                 DoEmitTypeParameter (ec);
6143                         else
6144                                 DoEmit (ec, true);
6145                 }
6146
6147                 public override void EmitStatement (EmitContext ec)
6148                 {
6149                         if (is_type_parameter)
6150                                 throw new InvalidOperationException ();
6151
6152                         if (DoEmit (ec, false))
6153                                 ec.ig.Emit (OpCodes.Pop);
6154                 }
6155
6156                 public void AddressOf (EmitContext ec, AddressOp Mode)
6157                 {
6158                         if (is_type_parameter)
6159                                 throw new InvalidOperationException ();
6160
6161                         if (!type.IsValueType){
6162                                 //
6163                                 // We throw an exception.  So far, I believe we only need to support
6164                                 // value types:
6165                                 // foreach (int j in new StructType ())
6166                                 // see bug 42390
6167                                 //
6168                                 throw new Exception ("AddressOf should not be used for classes");
6169                         }
6170
6171                         if (!value_target_set)
6172                                 value_target = new LocalTemporary (ec, type);
6173
6174                         IMemoryLocation ml = (IMemoryLocation) value_target;
6175                         ml.AddressOf (ec, AddressOp.Store);
6176                         if (method != null)
6177                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
6178
6179                         if (method == null)
6180                                 ec.ig.Emit (OpCodes.Initobj, type);
6181                         else
6182                                 ec.ig.Emit (OpCodes.Call, (ConstructorInfo) method);
6183
6184                         ((IMemoryLocation) value_target).AddressOf (ec, Mode);
6185                 }
6186         }
6187
6188         /// <summary>
6189         ///   14.5.10.2: Represents an array creation expression.
6190         /// </summary>
6191         ///
6192         /// <remarks>
6193         ///   There are two possible scenarios here: one is an array creation
6194         ///   expression that specifies the dimensions and optionally the
6195         ///   initialization data and the other which does not need dimensions
6196         ///   specified but where initialization data is mandatory.
6197         /// </remarks>
6198         public class ArrayCreation : Expression {
6199                 Expression requested_base_type;
6200                 ArrayList initializers;
6201
6202                 //
6203                 // The list of Argument types.
6204                 // This is used to construct the `newarray' or constructor signature
6205                 //
6206                 ArrayList arguments;
6207
6208                 //
6209                 // Method used to create the array object.
6210                 //
6211                 MethodBase new_method = null;
6212
6213                 Type array_element_type;
6214                 Type underlying_type;
6215                 bool is_one_dimensional = false;
6216                 bool is_builtin_type = false;
6217                 bool expect_initializers = false;
6218                 int num_arguments = 0;
6219                 int dimensions = 0;
6220                 string rank;
6221
6222                 ArrayList array_data;
6223
6224                 Hashtable bounds;
6225
6226                 //
6227                 // The number of array initializers that we can handle
6228                 // via the InitializeArray method - through EmitStaticInitializers
6229                 //
6230                 int num_automatic_initializers;
6231
6232                 const int max_automatic_initializers = 6;
6233
6234                 public ArrayCreation (Expression requested_base_type, ArrayList exprs, string rank, ArrayList initializers, Location l)
6235                 {
6236                         this.requested_base_type = requested_base_type;
6237                         this.initializers = initializers;
6238                         this.rank = rank;
6239                         loc = l;
6240
6241                         arguments = new ArrayList ();
6242
6243                         foreach (Expression e in exprs) {
6244                                 arguments.Add (new Argument (e, Argument.AType.Expression));
6245                                 num_arguments++;
6246                         }
6247                 }
6248
6249                 public ArrayCreation (Expression requested_base_type, string rank, ArrayList initializers, Location l)
6250                 {
6251                         this.requested_base_type = requested_base_type;
6252                         this.initializers = initializers;
6253                         this.rank = rank;
6254                         loc = l;
6255
6256                         //this.rank = rank.Substring (0, rank.LastIndexOf ('['));
6257                         //
6258                         //string tmp = rank.Substring (rank.LastIndexOf ('['));
6259                         //
6260                         //dimensions = tmp.Length - 1;
6261                         expect_initializers = true;
6262                 }
6263
6264                 public Expression FormArrayType (Expression base_type, int idx_count, string rank)
6265                 {
6266                         StringBuilder sb = new StringBuilder (rank);
6267
6268                         sb.Append ("[");
6269                         for (int i = 1; i < idx_count; i++)
6270                                 sb.Append (",");
6271
6272                         sb.Append ("]");
6273
6274                         return new ComposedCast (base_type, sb.ToString (), loc);
6275                 }
6276
6277                 void Error_IncorrectArrayInitializer ()
6278                 {
6279                         Error (178, "Incorrectly structured array initializer");
6280                 }
6281
6282                 public bool CheckIndices (EmitContext ec, ArrayList probe, int idx, bool specified_dims)
6283                 {
6284                         if (specified_dims) {
6285                                 Argument a = (Argument) arguments [idx];
6286
6287                                 if (!a.Resolve (ec, loc))
6288                                         return false;
6289
6290                                 if (!(a.Expr is Constant)) {
6291                                         Error (150, "A constant value is expected");
6292                                         return false;
6293                                 }
6294
6295                                 int value = (int) ((Constant) a.Expr).GetValue ();
6296
6297                                 if (value != probe.Count) {
6298                                         Error_IncorrectArrayInitializer ();
6299                                         return false;
6300                                 }
6301
6302                                 bounds [idx] = value;
6303                         }
6304
6305                         int child_bounds = -1;
6306                         for (int i = 0; i < probe.Count; ++i) {
6307                                 object o = probe [i];
6308                                 if (o is ArrayList) {
6309                                         ArrayList sub_probe = o as ArrayList;
6310                                         int current_bounds = sub_probe.Count;
6311
6312                                         if (child_bounds == -1)
6313                                                 child_bounds = current_bounds;
6314
6315                                         else if (child_bounds != current_bounds){
6316                                                 Error_IncorrectArrayInitializer ();
6317                                                 return false;
6318                                         }
6319                                         if (specified_dims && (idx + 1 >= arguments.Count)){
6320                                                 Error (623, "Array initializers can only be used in a variable or field initializer, try using the new expression");
6321                                                 return false;
6322                                         }
6323
6324                                         bool ret = CheckIndices (ec, sub_probe, idx + 1, specified_dims);
6325                                         if (!ret)
6326                                                 return false;
6327                                 } else {
6328                                         if (child_bounds != -1){
6329                                                 Error_IncorrectArrayInitializer ();
6330                                                 return false;
6331                                         }
6332
6333                                         Expression tmp = (Expression) o;
6334                                         tmp = tmp.Resolve (ec);
6335                                         probe [i] = tmp;
6336                                         if (tmp == null)
6337                                                 return false;
6338
6339                                         // Console.WriteLine ("I got: " + tmp);
6340                                         // Handle initialization from vars, fields etc.
6341
6342                                         Expression conv = Convert.ImplicitConversionRequired (
6343                                                 ec, tmp, underlying_type, loc);
6344
6345                                         if (conv == null)
6346                                                 return false;
6347
6348                                         if (conv is StringConstant || conv is DecimalConstant || conv is NullCast) {
6349                                                 // These are subclasses of Constant that can appear as elements of an
6350                                                 // array that cannot be statically initialized (with num_automatic_initializers
6351                                                 // > max_automatic_initializers), so num_automatic_initializers should be left as zero.
6352                                                 array_data.Add (conv);
6353                                         } else if (conv is Constant) {
6354                                                 // These are the types of Constant that can appear in arrays that can be
6355                                                 // statically allocated.
6356                                                 array_data.Add (conv);
6357                                                 num_automatic_initializers++;
6358                                         } else
6359                                                 array_data.Add (conv);
6360                                 }
6361                         }
6362
6363                         return true;
6364                 }
6365
6366                 public void UpdateIndices (EmitContext ec)
6367                 {
6368                         int i = 0;
6369                         for (ArrayList probe = initializers; probe != null;) {
6370                                 if (probe.Count > 0 && probe [0] is ArrayList) {
6371                                         Expression e = new IntConstant (probe.Count);
6372                                         arguments.Add (new Argument (e, Argument.AType.Expression));
6373
6374                                         bounds [i++] =  probe.Count;
6375
6376                                         probe = (ArrayList) probe [0];
6377
6378                                 } else {
6379                                         Expression e = new IntConstant (probe.Count);
6380                                         arguments.Add (new Argument (e, Argument.AType.Expression));
6381
6382                                         bounds [i++] = probe.Count;
6383                                         probe = null;
6384                                 }
6385                         }
6386
6387                 }
6388
6389                 public bool ValidateInitializers (EmitContext ec, Type array_type)
6390                 {
6391                         if (initializers == null) {
6392                                 if (expect_initializers)
6393                                         return false;
6394                                 else
6395                                         return true;
6396                         }
6397
6398                         if (underlying_type == null)
6399                                 return false;
6400
6401                         //
6402                         // We use this to store all the date values in the order in which we
6403                         // will need to store them in the byte blob later
6404                         //
6405                         array_data = new ArrayList ();
6406                         bounds = new Hashtable ();
6407
6408                         bool ret;
6409
6410                         if (arguments != null) {
6411                                 ret = CheckIndices (ec, initializers, 0, true);
6412                                 return ret;
6413                         } else {
6414                                 arguments = new ArrayList ();
6415
6416                                 ret = CheckIndices (ec, initializers, 0, false);
6417
6418                                 if (!ret)
6419                                         return false;
6420
6421                                 UpdateIndices (ec);
6422
6423                                 if (arguments.Count != dimensions) {
6424                                         Error_IncorrectArrayInitializer ();
6425                                         return false;
6426                                 }
6427
6428                                 return ret;
6429                         }
6430                 }
6431
6432                 //
6433                 // Creates the type of the array
6434                 //
6435                 bool LookupType (EmitContext ec)
6436                 {
6437                         StringBuilder array_qualifier = new StringBuilder (rank);
6438
6439                         //
6440                         // `In the first form allocates an array instace of the type that results
6441                         // from deleting each of the individual expression from the expression list'
6442                         //
6443                         if (num_arguments > 0) {
6444                                 array_qualifier.Append ("[");
6445                                 for (int i = num_arguments-1; i > 0; i--)
6446                                         array_qualifier.Append (",");
6447                                 array_qualifier.Append ("]");
6448                         }
6449
6450                         //
6451                         // Lookup the type
6452                         //
6453                         TypeExpr array_type_expr;
6454                         array_type_expr = new ComposedCast (requested_base_type, array_qualifier.ToString (), loc);
6455                         array_type_expr = array_type_expr.ResolveAsTypeTerminal (ec);
6456                         if (array_type_expr == null)
6457                                 return false;
6458
6459                         type = array_type_expr.Type;
6460
6461                         if (!type.IsArray) {
6462                                 Error (622, "Can only use array initializer expressions to assign to array types. Try using a new expression instead.");
6463                                 return false;
6464                         }
6465                         underlying_type = TypeManager.GetElementType (type);
6466                         dimensions = type.GetArrayRank ();
6467
6468                         return true;
6469                 }
6470
6471                 public override Expression DoResolve (EmitContext ec)
6472                 {
6473                         int arg_count;
6474
6475                         if (!LookupType (ec))
6476                                 return null;
6477
6478                         //
6479                         // First step is to validate the initializers and fill
6480                         // in any missing bits
6481                         //
6482                         if (!ValidateInitializers (ec, type))
6483                                 return null;
6484
6485                         if (arguments == null)
6486                                 arg_count = 0;
6487                         else {
6488                                 arg_count = arguments.Count;
6489                                 foreach (Argument a in arguments){
6490                                         if (!a.Resolve (ec, loc))
6491                                                 return null;
6492
6493                                         Expression real_arg = ExpressionToArrayArgument (ec, a.Expr, loc);
6494                                         if (real_arg == null)
6495                                                 return null;
6496
6497                                         a.Expr = real_arg;
6498                                 }
6499                         }
6500
6501                         array_element_type = TypeManager.GetElementType (type);
6502
6503                         if (array_element_type.IsAbstract && array_element_type.IsSealed) {
6504                                 Report.Error (719, loc, "'{0}': array elements cannot be of static type", TypeManager.CSharpName (array_element_type));
6505                                 return null;
6506                         }
6507
6508                         if (arg_count == 1) {
6509                                 is_one_dimensional = true;
6510                                 eclass = ExprClass.Value;
6511                                 return this;
6512                         }
6513
6514                         is_builtin_type = TypeManager.IsBuiltinType (type);
6515
6516                         if (is_builtin_type) {
6517                                 Expression ml;
6518
6519                                 ml = MemberLookup (ec, type, ".ctor", MemberTypes.Constructor,
6520                                                    AllBindingFlags, loc);
6521
6522                                 if (!(ml is MethodGroupExpr)) {
6523                                         ml.Error_UnexpectedKind ("method group", loc);
6524                                         return null;
6525                                 }
6526
6527                                 if (ml == null) {
6528                                         Error (-6, "New invocation: Can not find a constructor for " +
6529                                                       "this argument list");
6530                                         return null;
6531                                 }
6532
6533                                 new_method = Invocation.OverloadResolve (
6534                                         ec, (MethodGroupExpr) ml, arguments, false, loc);
6535
6536                                 if (new_method == null) {
6537                                         Error (-6, "New invocation: Can not find a constructor for " +
6538                                                       "this argument list");
6539                                         return null;
6540                                 }
6541
6542                                 eclass = ExprClass.Value;
6543                                 return this;
6544                         } else {
6545                                 ModuleBuilder mb = CodeGen.Module.Builder;
6546                                 ArrayList args = new ArrayList ();
6547
6548                                 if (arguments != null) {
6549                                         for (int i = 0; i < arg_count; i++)
6550                                                 args.Add (TypeManager.int32_type);
6551                                 }
6552
6553                                 Type [] arg_types = null;
6554
6555                                 if (args.Count > 0)
6556                                         arg_types = new Type [args.Count];
6557
6558                                 args.CopyTo (arg_types, 0);
6559
6560                                 new_method = mb.GetArrayMethod (type, ".ctor", CallingConventions.HasThis, null,
6561                                                             arg_types);
6562
6563                                 if (new_method == null) {
6564                                         Error (-6, "New invocation: Can not find a constructor for " +
6565                                                       "this argument list");
6566                                         return null;
6567                                 }
6568
6569                                 eclass = ExprClass.Value;
6570                                 return this;
6571                         }
6572                 }
6573
6574                 public static byte [] MakeByteBlob (ArrayList array_data, Type underlying_type, Location loc)
6575                 {
6576                         int factor;
6577                         byte [] data;
6578                         byte [] element;
6579                         int count = array_data.Count;
6580
6581                         if (underlying_type.IsEnum)
6582                                 underlying_type = TypeManager.EnumToUnderlying (underlying_type);
6583
6584                         factor = GetTypeSize (underlying_type);
6585                         if (factor == 0)
6586                                 throw new Exception ("unrecognized type in MakeByteBlob: " + underlying_type);
6587
6588                         data = new byte [(count * factor + 4) & ~3];
6589                         int idx = 0;
6590
6591                         for (int i = 0; i < count; ++i) {
6592                                 object v = array_data [i];
6593
6594                                 if (v is EnumConstant)
6595                                         v = ((EnumConstant) v).Child;
6596
6597                                 if (v is Constant && !(v is StringConstant))
6598                                         v = ((Constant) v).GetValue ();
6599                                 else {
6600                                         idx += factor;
6601                                         continue;
6602                                 }
6603
6604                                 if (underlying_type == TypeManager.int64_type){
6605                                         if (!(v is Expression)){
6606                                                 long val = (long) v;
6607
6608                                                 for (int j = 0; j < factor; ++j) {
6609                                                         data [idx + j] = (byte) (val & 0xFF);
6610                                                         val = (val >> 8);
6611                                                 }
6612                                         }
6613                                 } else if (underlying_type == TypeManager.uint64_type){
6614                                         if (!(v is Expression)){
6615                                                 ulong val = (ulong) v;
6616
6617                                                 for (int j = 0; j < factor; ++j) {
6618                                                         data [idx + j] = (byte) (val & 0xFF);
6619                                                         val = (val >> 8);
6620                                                 }
6621                                         }
6622                                 } else if (underlying_type == TypeManager.float_type) {
6623                                         if (!(v is Expression)){
6624                                                 element = BitConverter.GetBytes ((float) v);
6625
6626                                                 for (int j = 0; j < factor; ++j)
6627                                                         data [idx + j] = element [j];
6628                                         }
6629                                 } else if (underlying_type == TypeManager.double_type) {
6630                                         if (!(v is Expression)){
6631                                                 element = BitConverter.GetBytes ((double) v);
6632
6633                                                 for (int j = 0; j < factor; ++j)
6634                                                         data [idx + j] = element [j];
6635                                         }
6636                                 } else if (underlying_type == TypeManager.char_type){
6637                                         if (!(v is Expression)){
6638                                                 int val = (int) ((char) v);
6639
6640                                                 data [idx] = (byte) (val & 0xff);
6641                                                 data [idx+1] = (byte) (val >> 8);
6642                                         }
6643                                 } else if (underlying_type == TypeManager.short_type){
6644                                         if (!(v is Expression)){
6645                                                 int val = (int) ((short) v);
6646
6647                                                 data [idx] = (byte) (val & 0xff);
6648                                                 data [idx+1] = (byte) (val >> 8);
6649                                         }
6650                                 } else if (underlying_type == TypeManager.ushort_type){
6651                                         if (!(v is Expression)){
6652                                                 int val = (int) ((ushort) v);
6653
6654                                                 data [idx] = (byte) (val & 0xff);
6655                                                 data [idx+1] = (byte) (val >> 8);
6656                                         }
6657                                 } else if (underlying_type == TypeManager.int32_type) {
6658                                         if (!(v is Expression)){
6659                                                 int val = (int) v;
6660
6661                                                 data [idx]   = (byte) (val & 0xff);
6662                                                 data [idx+1] = (byte) ((val >> 8) & 0xff);
6663                                                 data [idx+2] = (byte) ((val >> 16) & 0xff);
6664                                                 data [idx+3] = (byte) (val >> 24);
6665                                         }
6666                                 } else if (underlying_type == TypeManager.uint32_type) {
6667                                         if (!(v is Expression)){
6668                                                 uint val = (uint) v;
6669
6670                                                 data [idx]   = (byte) (val & 0xff);
6671                                                 data [idx+1] = (byte) ((val >> 8) & 0xff);
6672                                                 data [idx+2] = (byte) ((val >> 16) & 0xff);
6673                                                 data [idx+3] = (byte) (val >> 24);
6674                                         }
6675                                 } else if (underlying_type == TypeManager.sbyte_type) {
6676                                         if (!(v is Expression)){
6677                                                 sbyte val = (sbyte) v;
6678                                                 data [idx] = (byte) val;
6679                                         }
6680                                 } else if (underlying_type == TypeManager.byte_type) {
6681                                         if (!(v is Expression)){
6682                                                 byte val = (byte) v;
6683                                                 data [idx] = (byte) val;
6684                                         }
6685                                 } else if (underlying_type == TypeManager.bool_type) {
6686                                         if (!(v is Expression)){
6687                                                 bool val = (bool) v;
6688                                                 data [idx] = (byte) (val ? 1 : 0);
6689                                         }
6690                                 } else if (underlying_type == TypeManager.decimal_type){
6691                                         if (!(v is Expression)){
6692                                                 int [] bits = Decimal.GetBits ((decimal) v);
6693                                                 int p = idx;
6694
6695                                                 // FIXME: For some reason, this doesn't work on the MS runtime.
6696                                                 int [] nbits = new int [4];
6697                                                 nbits [0] = bits [3];
6698                                                 nbits [1] = bits [2];
6699                                                 nbits [2] = bits [0];
6700                                                 nbits [3] = bits [1];
6701
6702                                                 for (int j = 0; j < 4; j++){
6703                                                         data [p++] = (byte) (nbits [j] & 0xff);
6704                                                         data [p++] = (byte) ((nbits [j] >> 8) & 0xff);
6705                                                         data [p++] = (byte) ((nbits [j] >> 16) & 0xff);
6706                                                         data [p++] = (byte) (nbits [j] >> 24);
6707                                                 }
6708                                         }
6709                                 } else
6710                                         throw new Exception ("Unrecognized type in MakeByteBlob: " + underlying_type);
6711
6712                                 idx += factor;
6713                         }
6714
6715                         return data;
6716                 }
6717
6718                 //
6719                 // Emits the initializers for the array
6720                 //
6721                 void EmitStaticInitializers (EmitContext ec)
6722                 {
6723                         //
6724                         // First, the static data
6725                         //
6726                         FieldBuilder fb;
6727                         ILGenerator ig = ec.ig;
6728
6729                         byte [] data = MakeByteBlob (array_data, underlying_type, loc);
6730
6731                         fb = RootContext.MakeStaticData (data);
6732
6733                         ig.Emit (OpCodes.Dup);
6734                         ig.Emit (OpCodes.Ldtoken, fb);
6735                         ig.Emit (OpCodes.Call,
6736                                  TypeManager.void_initializearray_array_fieldhandle);
6737                 }
6738
6739                 //
6740                 // Emits pieces of the array that can not be computed at compile
6741                 // time (variables and string locations).
6742                 //
6743                 // This always expect the top value on the stack to be the array
6744                 //
6745                 void EmitDynamicInitializers (EmitContext ec)
6746                 {
6747                         ILGenerator ig = ec.ig;
6748                         int dims = bounds.Count;
6749                         int [] current_pos = new int [dims];
6750                         int top = array_data.Count;
6751
6752                         MethodInfo set = null;
6753
6754                         if (dims != 1){
6755                                 Type [] args;
6756                                 ModuleBuilder mb = null;
6757                                 mb = CodeGen.Module.Builder;
6758                                 args = new Type [dims + 1];
6759
6760                                 int j;
6761                                 for (j = 0; j < dims; j++)
6762                                         args [j] = TypeManager.int32_type;
6763
6764                                 args [j] = array_element_type;
6765
6766                                 set = mb.GetArrayMethod (
6767                                         type, "Set",
6768                                         CallingConventions.HasThis | CallingConventions.Standard,
6769                                         TypeManager.void_type, args);
6770                         }
6771
6772                         for (int i = 0; i < top; i++){
6773
6774                                 Expression e = null;
6775
6776                                 if (array_data [i] is Expression)
6777                                         e = (Expression) array_data [i];
6778
6779                                 if (e != null) {
6780                                         //
6781                                         // Basically we do this for string literals and
6782                                         // other non-literal expressions
6783                                         //
6784                                         if (e is EnumConstant){
6785                                                 e = ((EnumConstant) e).Child;
6786                                         }
6787
6788                                         if (e is StringConstant || e is DecimalConstant || !(e is Constant) ||
6789                                             num_automatic_initializers <= max_automatic_initializers) {
6790                                                 Type etype = e.Type;
6791
6792                                                 ig.Emit (OpCodes.Dup);
6793
6794                                                 for (int idx = 0; idx < dims; idx++)
6795                                                         IntConstant.EmitInt (ig, current_pos [idx]);
6796
6797                                                 //
6798                                                 // If we are dealing with a struct, get the
6799                                                 // address of it, so we can store it.
6800                                                 //
6801                                                 if ((dims == 1) && etype.IsValueType &&
6802                                                     (!TypeManager.IsBuiltinOrEnum (etype) ||
6803                                                      etype == TypeManager.decimal_type)) {
6804                                                         if (e is New){
6805                                                                 New n = (New) e;
6806
6807                                                                 //
6808                                                                 // Let new know that we are providing
6809                                                                 // the address where to store the results
6810                                                                 //
6811                                                                 n.DisableTemporaryValueType ();
6812                                                         }
6813
6814                                                         ig.Emit (OpCodes.Ldelema, etype);
6815                                                 }
6816
6817                                                 e.Emit (ec);
6818
6819                                                 if (dims == 1) {
6820                                                         bool is_stobj, has_type_arg;
6821                                                         OpCode op = ArrayAccess.GetStoreOpcode (
6822                                                                 etype, out is_stobj,
6823                                                                 out has_type_arg);
6824                                                         if (is_stobj)
6825                                                                 ig.Emit (OpCodes.Stobj, etype);
6826                                                         else if (has_type_arg)
6827                                                                 ig.Emit (op, etype);
6828                                                         else
6829                                                                 ig.Emit (op);
6830                                                 } else
6831                                                         ig.Emit (OpCodes.Call, set);
6832                                         }
6833                                 }
6834
6835                                 //
6836                                 // Advance counter
6837                                 //
6838                                 for (int j = dims - 1; j >= 0; j--){
6839                                         current_pos [j]++;
6840                                         if (current_pos [j] < (int) bounds [j])
6841                                                 break;
6842                                         current_pos [j] = 0;
6843                                 }
6844                         }
6845                 }
6846
6847                 void EmitArrayArguments (EmitContext ec)
6848                 {
6849                         ILGenerator ig = ec.ig;
6850
6851                         foreach (Argument a in arguments) {
6852                                 Type atype = a.Type;
6853                                 a.Emit (ec);
6854
6855                                 if (atype == TypeManager.uint64_type)
6856                                         ig.Emit (OpCodes.Conv_Ovf_U4);
6857                                 else if (atype == TypeManager.int64_type)
6858                                         ig.Emit (OpCodes.Conv_Ovf_I4);
6859                         }
6860                 }
6861
6862                 public override void Emit (EmitContext ec)
6863                 {
6864                         ILGenerator ig = ec.ig;
6865
6866                         EmitArrayArguments (ec);
6867                         if (is_one_dimensional)
6868                                 ig.Emit (OpCodes.Newarr, array_element_type);
6869                         else {
6870                                 if (is_builtin_type)
6871                                         ig.Emit (OpCodes.Newobj, (ConstructorInfo) new_method);
6872                                 else
6873                                         ig.Emit (OpCodes.Newobj, (MethodInfo) new_method);
6874                         }
6875
6876                         if (initializers != null){
6877                                 //
6878                                 // FIXME: Set this variable correctly.
6879                                 //
6880                                 bool dynamic_initializers = true;
6881
6882                                 // This will never be true for array types that cannot be statically
6883                                 // initialized. num_automatic_initializers will always be zero.  See
6884                                 // CheckIndices.
6885                                         if (num_automatic_initializers > max_automatic_initializers)
6886                                                 EmitStaticInitializers (ec);
6887
6888                                 if (dynamic_initializers)
6889                                         EmitDynamicInitializers (ec);
6890                         }
6891                 }
6892
6893                 public object EncodeAsAttribute ()
6894                 {
6895                         if (!is_one_dimensional){
6896                                 Report.Error (-211, Location, "attribute can not encode multi-dimensional arrays");
6897                                 return null;
6898                         }
6899
6900                         if (array_data == null){
6901                                 Report.Error (-212, Location, "array should be initialized when passing it to an attribute");
6902                                 return null;
6903                         }
6904
6905                         object [] ret = new object [array_data.Count];
6906                         int i = 0;
6907                         foreach (Expression e in array_data){
6908                                 object v;
6909
6910                                 if (e is NullLiteral)
6911                                         v = null;
6912                                 else {
6913                                         if (!Attribute.GetAttributeArgumentExpression (e, Location, array_element_type, out v))
6914                                                 return null;
6915                                 }
6916                                 ret [i++] = v;
6917                         }
6918                         return ret;
6919                 }
6920         }
6921
6922         /// <summary>
6923         ///   Represents the `this' construct
6924         /// </summary>
6925         public class This : Expression, IAssignMethod, IMemoryLocation, IVariable {
6926
6927                 Block block;
6928                 VariableInfo variable_info;
6929
6930                 public This (Block block, Location loc)
6931                 {
6932                         this.loc = loc;
6933                         this.block = block;
6934                 }
6935
6936                 public This (Location loc)
6937                 {
6938                         this.loc = loc;
6939                 }
6940
6941                 public VariableInfo VariableInfo {
6942                         get { return variable_info; }
6943                 }
6944
6945                 public bool VerifyFixed (bool is_expression)
6946                 {
6947                         if ((variable_info == null) || (variable_info.LocalInfo == null))
6948                                 return false;
6949                         else
6950                                 return variable_info.LocalInfo.IsFixed;
6951                 }
6952
6953                 public bool ResolveBase (EmitContext ec)
6954                 {
6955                         eclass = ExprClass.Variable;
6956
6957                         if (ec.TypeContainer.CurrentType != null)
6958                                 type = ec.TypeContainer.CurrentType;
6959                         else
6960                                 type = ec.ContainerType;
6961
6962                         if (ec.IsStatic) {
6963                                 Error (26, "Keyword this not valid in static code");
6964                                 return false;
6965                         }
6966
6967                         if ((block != null) && (block.ThisVariable != null))
6968                                 variable_info = block.ThisVariable.VariableInfo;
6969
6970                         if (ec.CurrentAnonymousMethod != null)
6971                                 ec.CaptureThis ();
6972
6973                         return true;
6974                 }
6975
6976                 public override Expression DoResolve (EmitContext ec)
6977                 {
6978                         if (!ResolveBase (ec))
6979                                 return null;
6980
6981                         if ((variable_info != null) && !variable_info.IsAssigned (ec)) {
6982                                 Error (188, "The this object cannot be used before all " +
6983                                        "of its fields are assigned to");
6984                                 variable_info.SetAssigned (ec);
6985                                 return this;
6986                         }
6987
6988                         if (ec.IsFieldInitializer) {
6989                                 Error (27, "Keyword `this' can't be used outside a constructor, " +
6990                                        "a method or a property.");
6991                                 return null;
6992                         }
6993
6994                         return this;
6995                 }
6996
6997                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
6998                 {
6999                         if (!ResolveBase (ec))
7000                                 return null;
7001
7002                         if (variable_info != null)
7003                                 variable_info.SetAssigned (ec);
7004
7005                         if (ec.TypeContainer is Class){
7006                                 Error (1604, "Cannot assign to 'this' because it is read-only");
7007                                 return null;
7008                         }
7009
7010                         return this;
7011                 }
7012
7013                 public void Emit (EmitContext ec, bool leave_copy)
7014                 {
7015                         Emit (ec);
7016                         if (leave_copy)
7017                                 ec.ig.Emit (OpCodes.Dup);
7018                 }
7019
7020                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
7021                 {
7022                         ILGenerator ig = ec.ig;
7023
7024                         if (ec.TypeContainer is Struct){
7025                                 ec.EmitThis ();
7026                                 source.Emit (ec);
7027                                 if (leave_copy)
7028                                         ec.ig.Emit (OpCodes.Dup);
7029                                 ig.Emit (OpCodes.Stobj, type);
7030                         } else {
7031                                 throw new Exception ("how did you get here");
7032                         }
7033                 }
7034
7035                 public override void Emit (EmitContext ec)
7036                 {
7037                         ILGenerator ig = ec.ig;
7038
7039                         ec.EmitThis ();
7040                         if (ec.TypeContainer is Struct)
7041                                 ig.Emit (OpCodes.Ldobj, type);
7042                 }
7043
7044                 public override int GetHashCode()
7045                 {
7046                         return block.GetHashCode ();
7047                 }
7048
7049                 public override bool Equals (object obj)
7050                 {
7051                         This t = obj as This;
7052                         if (t == null)
7053                                 return false;
7054
7055                         return block == t.block;
7056                 }
7057
7058                 public void AddressOf (EmitContext ec, AddressOp mode)
7059                 {
7060                         ec.EmitThis ();
7061
7062                         // FIMXE
7063                         // FIGURE OUT WHY LDARG_S does not work
7064                         //
7065                         // consider: struct X { int val; int P { set { val = value; }}}
7066                         //
7067                         // Yes, this looks very bad. Look at `NOTAS' for
7068                         // an explanation.
7069                         // ec.ig.Emit (OpCodes.Ldarga_S, (byte) 0);
7070                 }
7071         }
7072
7073         /// <summary>
7074         ///   Represents the `__arglist' construct
7075         /// </summary>
7076         public class ArglistAccess : Expression
7077         {
7078                 public ArglistAccess (Location loc)
7079                 {
7080                         this.loc = loc;
7081                 }
7082
7083                 public bool ResolveBase (EmitContext ec)
7084                 {
7085                         eclass = ExprClass.Variable;
7086                         type = TypeManager.runtime_argument_handle_type;
7087                         return true;
7088                 }
7089
7090                 public override Expression DoResolve (EmitContext ec)
7091                 {
7092                         if (!ResolveBase (ec))
7093                                 return null;
7094
7095                         if (ec.IsFieldInitializer || !ec.CurrentBlock.HasVarargs) {
7096                                 Error (190, "The __arglist construct is valid only within " +
7097                                        "a variable argument method.");
7098                                 return null;
7099                         }
7100
7101                         return this;
7102                 }
7103
7104                 public override void Emit (EmitContext ec)
7105                 {
7106                         ec.ig.Emit (OpCodes.Arglist);
7107                 }
7108         }
7109
7110         /// <summary>
7111         ///   Represents the `__arglist (....)' construct
7112         /// </summary>
7113         public class Arglist : Expression
7114         {
7115                 public readonly Argument[] Arguments;
7116
7117                 public Arglist (Argument[] args, Location l)
7118                 {
7119                         Arguments = args;
7120                         loc = l;
7121                 }
7122
7123                 public Type[] ArgumentTypes {
7124                         get {
7125                                 Type[] retval = new Type [Arguments.Length];
7126                                 for (int i = 0; i < Arguments.Length; i++)
7127                                         retval [i] = Arguments [i].Type;
7128                                 return retval;
7129                         }
7130                 }
7131
7132                 public override Expression DoResolve (EmitContext ec)
7133                 {
7134                         eclass = ExprClass.Variable;
7135                         type = TypeManager.runtime_argument_handle_type;
7136
7137                         foreach (Argument arg in Arguments) {
7138                                 if (!arg.Resolve (ec, loc))
7139                                         return null;
7140                         }
7141
7142                         return this;
7143                 }
7144
7145                 public override void Emit (EmitContext ec)
7146                 {
7147                         foreach (Argument arg in Arguments)
7148                                 arg.Emit (ec);
7149                 }
7150         }
7151
7152         //
7153         // This produces the value that renders an instance, used by the iterators code
7154         //
7155         public class ProxyInstance : Expression, IMemoryLocation  {
7156                 public override Expression DoResolve (EmitContext ec)
7157                 {
7158                         eclass = ExprClass.Variable;
7159                         type = ec.ContainerType;
7160                         return this;
7161                 }
7162
7163                 public override void Emit (EmitContext ec)
7164                 {
7165                         ec.ig.Emit (OpCodes.Ldarg_0);
7166
7167                 }
7168
7169                 public void AddressOf (EmitContext ec, AddressOp mode)
7170                 {
7171                         ec.ig.Emit (OpCodes.Ldarg_0);
7172                 }
7173         }
7174
7175         /// <summary>
7176         ///   Implements the typeof operator
7177         /// </summary>
7178         public class TypeOf : Expression {
7179                 public Expression QueriedType;
7180                 protected Type typearg;
7181
7182                 public TypeOf (Expression queried_type, Location l)
7183                 {
7184                         QueriedType = queried_type;
7185                         loc = l;
7186                 }
7187
7188                 public override Expression DoResolve (EmitContext ec)
7189                 {
7190                         TypeExpr texpr = QueriedType.ResolveAsTypeTerminal (ec);
7191                         if (texpr == null)
7192                                 return null;
7193
7194                         typearg = texpr.Type;
7195
7196                         if (typearg == TypeManager.void_type) {
7197                                 Error (673, "System.Void cannot be used from C# - " +
7198                                        "use typeof (void) to get the void type object");
7199                                 return null;
7200                         }
7201
7202                         if (typearg.IsPointer && !ec.InUnsafe){
7203                                 UnsafeError (loc);
7204                                 return null;
7205                         }
7206                         CheckObsoleteAttribute (typearg);
7207
7208                         type = TypeManager.type_type;
7209                         eclass = ExprClass.Type;
7210                         return this;
7211                 }
7212
7213                 public override void Emit (EmitContext ec)
7214                 {
7215                         ec.ig.Emit (OpCodes.Ldtoken, typearg);
7216                         ec.ig.Emit (OpCodes.Call, TypeManager.system_type_get_type_from_handle);
7217                 }
7218
7219                 public Type TypeArg {
7220                         get { return typearg; }
7221                 }
7222         }
7223
7224         /// <summary>
7225         ///   Implements the `typeof (void)' operator
7226         /// </summary>
7227         public class TypeOfVoid : TypeOf {
7228                 public TypeOfVoid (Location l) : base (null, l)
7229                 {
7230                         loc = l;
7231                 }
7232
7233                 public override Expression DoResolve (EmitContext ec)
7234                 {
7235                         type = TypeManager.type_type;
7236                         typearg = TypeManager.void_type;
7237                         eclass = ExprClass.Type;
7238                         return this;
7239                 }
7240         }
7241
7242         /// <summary>
7243         ///   Implements the sizeof expression
7244         /// </summary>
7245         public class SizeOf : Expression {
7246                 public Expression QueriedType;
7247                 Type type_queried;
7248
7249                 public SizeOf (Expression queried_type, Location l)
7250                 {
7251                         this.QueriedType = queried_type;
7252                         loc = l;
7253                 }
7254
7255                 public override Expression DoResolve (EmitContext ec)
7256                 {
7257                         TypeExpr texpr = QueriedType.ResolveAsTypeTerminal (ec);
7258                         if (texpr == null)
7259                                 return null;
7260
7261                         if (texpr is TypeParameterExpr){
7262                                 ((TypeParameterExpr)texpr).Error_CannotUseAsUnmanagedType (loc);
7263                                 return null;
7264                         }
7265
7266                         type_queried = texpr.Type;
7267
7268                         int size_of = GetTypeSize (type_queried);
7269                         if (size_of > 0) {
7270                                 return new IntConstant (size_of);
7271                         }
7272
7273                         if (!ec.InUnsafe) {
7274                                 Report.Error (233, loc, "'{0}' does not have a predefined size, therefore sizeof can only be used in an unsafe context (consider using System.Runtime.InteropServices.Marshal.SizeOf)",
7275                                          TypeManager.CSharpName (type_queried));
7276                                 return null;
7277                         }
7278
7279                         CheckObsoleteAttribute (type_queried);
7280
7281                         if (!TypeManager.IsUnmanagedType (type_queried)){
7282                                 Report.Error (208, loc, "Cannot take the size of an unmanaged type (" + TypeManager.CSharpName (type_queried) + ")");
7283                                 return null;
7284                         }
7285
7286                         type = TypeManager.int32_type;
7287                         eclass = ExprClass.Value;
7288                         return this;
7289                 }
7290
7291                 public override void Emit (EmitContext ec)
7292                 {
7293                         int size = GetTypeSize (type_queried);
7294
7295                         if (size == 0)
7296                                 ec.ig.Emit (OpCodes.Sizeof, type_queried);
7297                         else
7298                                 IntConstant.EmitInt (ec.ig, size);
7299                 }
7300         }
7301
7302         /// <summary>
7303         ///   Implements the member access expression
7304         /// </summary>
7305         public class MemberAccess : Expression {
7306                 public string Identifier;
7307                 protected Expression expr;
7308                 protected TypeArguments args;
7309
7310                 public MemberAccess (Expression expr, string id, Location l)
7311                 {
7312                         this.expr = expr;
7313                         Identifier = id;
7314                         loc = l;
7315                 }
7316
7317                 public MemberAccess (Expression expr, string id, TypeArguments args,
7318                                      Location l)
7319                         : this (expr, id, l)
7320                 {
7321                         this.args = args;
7322                 }
7323
7324                 public Expression Expr {
7325                         get {
7326                                 return expr;
7327                         }
7328                 }
7329
7330                 public virtual Expression DoResolve (EmitContext ec, Expression right_side,
7331                                                      ResolveFlags flags)
7332                 {
7333                         if (type != null)
7334                                 throw new Exception ();
7335
7336                         //
7337                         // Resolve the expression with flow analysis turned off, we'll do the definite
7338                         // assignment checks later.  This is because we don't know yet what the expression
7339                         // will resolve to - it may resolve to a FieldExpr and in this case we must do the
7340                         // definite assignment check on the actual field and not on the whole struct.
7341                         //
7342
7343                         SimpleName original = expr as SimpleName;
7344                         expr = expr.Resolve (ec, flags | ResolveFlags.Intermediate | ResolveFlags.DisableFlowAnalysis);
7345                         if (expr == null)
7346                                 return null;
7347
7348                         if (expr is Namespace) {
7349                                 Namespace ns = (Namespace) expr;
7350                                 string lookup_id = MemberName.MakeName (Identifier, args);
7351                                 FullNamedExpression retval = ns.Lookup (ec.DeclSpace, lookup_id, loc);
7352                                 if ((retval != null) && (args != null))
7353                                         retval = new ConstructedType (retval, args, loc).ResolveAsTypeStep (ec);
7354                                 if (retval == null)
7355                                         Report.Error (234, loc, "The type or namespace name `{0}' could not be found in namespace `{1}'", Identifier, ns.FullName);
7356                                 return retval;
7357                         }
7358
7359                         //
7360                         // TODO: I mailed Ravi about this, and apparently we can get rid
7361                         // of this and put it in the right place.
7362                         //
7363                         // Handle enums here when they are in transit.
7364                         // Note that we cannot afford to hit MemberLookup in this case because
7365                         // it will fail to find any members at all
7366                         //
7367
7368                         Type expr_type;
7369                         if (expr is TypeExpr){
7370                                 expr_type = expr.Type;
7371
7372                                 if (!ec.DeclSpace.CheckAccessLevel (expr_type)){
7373                                         Report.Error (122, loc, "'{0}' is inaccessible due to its protection level", expr_type);
7374                                         return null;
7375                                 }
7376
7377                                 if (expr_type == TypeManager.enum_type || expr_type.IsSubclassOf (TypeManager.enum_type)){
7378                                         Enum en = TypeManager.LookupEnum (expr_type);
7379
7380                                         if (en != null) {
7381                                                 object value = en.LookupEnumValue (Identifier, loc);
7382
7383                                                 if (value != null){
7384                                                         MemberCore mc = en.GetDefinition (Identifier);
7385                                                         ObsoleteAttribute oa = mc.GetObsoleteAttribute (en);
7386                                                         if (oa != null) {
7387                                                                 AttributeTester.Report_ObsoleteMessage (oa, mc.GetSignatureForError (), Location);
7388                                                         }
7389                                                         oa = en.GetObsoleteAttribute (en);
7390                                                         if (oa != null) {
7391                                                                 AttributeTester.Report_ObsoleteMessage (oa, en.GetSignatureForError (), Location);
7392                                                         }
7393
7394                                                         Constant c = Constantify (value, en.UnderlyingType);
7395                                                         return new EnumConstant (c, expr_type);
7396                                                 }
7397                                         } else {
7398                                                 CheckObsoleteAttribute (expr_type);
7399
7400                                                 FieldInfo fi = expr_type.GetField (Identifier);
7401                                                 if (fi != null) {
7402                                                         ObsoleteAttribute oa = AttributeTester.GetMemberObsoleteAttribute (fi);
7403                                                         if (oa != null)
7404                                                                 AttributeTester.Report_ObsoleteMessage (oa, TypeManager.GetFullNameSignature (fi), Location);
7405                                                 }
7406                                         }
7407                                 }
7408                         } else
7409                                 expr_type = expr.Type;
7410
7411                         if (expr_type.IsPointer){
7412                                 Error (23, "The `.' operator can not be applied to pointer operands (" +
7413                                        TypeManager.CSharpName (expr_type) + ")");
7414                                 return null;
7415                         }
7416
7417                         Expression member_lookup;
7418                         member_lookup = MemberLookup (
7419                                 ec, expr_type, expr_type, Identifier, loc);
7420                         if ((member_lookup == null) && (args != null)) {
7421                                 string lookup_id = MemberName.MakeName (Identifier, args);
7422                                 member_lookup = MemberLookup (
7423                                         ec, expr_type, expr_type, lookup_id, loc);
7424                         }
7425                         if (member_lookup == null) {
7426                                 MemberLookupFailed (
7427                                         ec, expr_type, expr_type, Identifier, null, false, loc);
7428                                 return null;
7429                         }
7430
7431                         if (member_lookup is TypeExpr) {
7432                                 if (!(expr is TypeExpr) &&
7433                                     (original == null || !original.IdenticalNameAndTypeName (ec, expr, loc))) {
7434                                         Error (572, "Can't reference type `" + Identifier + "' through an expression; try `" +
7435                                                member_lookup.Type + "' instead");
7436                                         return null;
7437                                 }
7438
7439                                 return member_lookup;
7440                         }
7441
7442                         MemberExpr me = (MemberExpr) member_lookup;
7443                         member_lookup = me.ResolveMemberAccess (ec, expr, loc, original);
7444                         if (member_lookup == null)
7445                                 return null;
7446
7447                         if (args != null) {
7448                                 MethodGroupExpr mg = member_lookup as MethodGroupExpr;
7449                                 if (mg == null)
7450                                         throw new InternalErrorException ();
7451
7452                                 return mg.ResolveGeneric (ec, args);
7453                         }
7454
7455                         // The following DoResolve/DoResolveLValue will do the definite assignment
7456                         // check.
7457
7458                         if (right_side != null)
7459                                 member_lookup = member_lookup.DoResolveLValue (ec, right_side);
7460                         else
7461                                 member_lookup = member_lookup.DoResolve (ec);
7462
7463                         return member_lookup;
7464                 }
7465
7466                 public override Expression DoResolve (EmitContext ec)
7467                 {
7468                         return DoResolve (ec, null, ResolveFlags.VariableOrValue | ResolveFlags.Type);
7469                 }
7470
7471                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
7472                 {
7473                         return DoResolve (ec, right_side, ResolveFlags.VariableOrValue | ResolveFlags.Type);
7474                 }
7475
7476                 public override FullNamedExpression ResolveAsTypeStep (EmitContext ec)
7477                 {
7478                         return ResolveNamespaceOrType (ec, false);
7479                 }
7480
7481                 public FullNamedExpression ResolveNamespaceOrType (EmitContext ec, bool silent)
7482                 {
7483                         FullNamedExpression new_expr = expr.ResolveAsTypeStep (ec);
7484
7485                         if (new_expr == null)
7486                                 return null;
7487
7488                         string lookup_id = MemberName.MakeName (Identifier, args);
7489
7490                         if (new_expr is Namespace) {
7491                                 Namespace ns = (Namespace) new_expr;
7492                                 FullNamedExpression retval = ns.Lookup (ec.DeclSpace, lookup_id, loc);
7493                                 if ((retval != null) && (args != null))
7494                                         retval = new ConstructedType (retval, args, loc).ResolveAsTypeStep (ec);
7495                                 if (!silent && retval == null)
7496                                         Report.Error (234, loc, "The type or namespace name `{0}' could not be found in namespace `{1}'", Identifier, ns.FullName);
7497                                 return retval;
7498                         }
7499
7500                         TypeExpr tnew_expr = new_expr.ResolveAsTypeTerminal (ec);
7501                         if (tnew_expr == null)
7502                                 return null;
7503
7504                         Type expr_type = tnew_expr.Type;
7505
7506                         if (expr_type.IsPointer){
7507                                 Error (23, "The `.' operator can not be applied to pointer operands (" +
7508                                        TypeManager.CSharpName (expr_type) + ")");
7509                                 return null;
7510                         }
7511
7512                         Expression member_lookup = MemberLookup (ec, expr_type, expr_type, lookup_id, loc);
7513                         if (member_lookup == null) {
7514                                 int errors = Report.Errors;
7515                                 MemberLookupFailed (ec, expr_type, expr_type, lookup_id, null, false, loc);
7516
7517                                 if (!silent && errors == Report.Errors)
7518                                         Report.Error (234, loc, "The type name `{0}' could not be found in type `{1}'",
7519                                                       lookup_id, new_expr.FullName);
7520                                 return null;
7521                         }
7522
7523                         if (!(member_lookup is TypeExpr)) {
7524                                 Report.Error (118, loc, "'{0}.{1}' denotes a '{2}', where a type was expected",
7525                                               new_expr.FullName, lookup_id, member_lookup.ExprClassName ());
7526                                 return null;
7527                         }
7528
7529                         TypeExpr texpr = member_lookup.ResolveAsTypeTerminal (ec);
7530                         if (texpr == null)
7531                                 return null;
7532
7533                         TypeArguments the_args = args;
7534                         if (TypeManager.HasGenericArguments (expr_type)) {
7535                                 Type[] decl_args = TypeManager.GetTypeArguments (expr_type);
7536
7537                                 TypeArguments new_args = new TypeArguments (loc);
7538                                 foreach (Type decl in decl_args)
7539                                         new_args.Add (new TypeExpression (decl, loc));
7540
7541                                 if (args != null)
7542                                         new_args.Add (args);
7543
7544                                 the_args = new_args;
7545                         }
7546
7547                         if (the_args != null) {
7548                                 ConstructedType ctype = new ConstructedType (texpr.Type, the_args, loc);
7549                                 return ctype.ResolveAsTypeStep (ec);
7550                         }
7551
7552                         return texpr;
7553                 }
7554
7555                 public override void Emit (EmitContext ec)
7556                 {
7557                         throw new Exception ("Should not happen");
7558                 }
7559
7560                 public override string ToString ()
7561                 {
7562                         return expr + "." + MemberName.MakeName (Identifier, args);
7563                 }
7564         }
7565
7566         /// <summary>
7567         ///   Implements checked expressions
7568         /// </summary>
7569         public class CheckedExpr : Expression {
7570
7571                 public Expression Expr;
7572
7573                 public CheckedExpr (Expression e, Location l)
7574                 {
7575                         Expr = e;
7576                         loc = l;
7577                 }
7578
7579                 public override Expression DoResolve (EmitContext ec)
7580                 {
7581                         bool last_check = ec.CheckState;
7582                         bool last_const_check = ec.ConstantCheckState;
7583
7584                         ec.CheckState = true;
7585                         ec.ConstantCheckState = true;
7586                         Expr = Expr.Resolve (ec);
7587                         ec.CheckState = last_check;
7588                         ec.ConstantCheckState = last_const_check;
7589
7590                         if (Expr == null)
7591                                 return null;
7592
7593                         if (Expr is Constant)
7594                                 return Expr;
7595
7596                         eclass = Expr.eclass;
7597                         type = Expr.Type;
7598                         return this;
7599                 }
7600
7601                 public override void Emit (EmitContext ec)
7602                 {
7603                         bool last_check = ec.CheckState;
7604                         bool last_const_check = ec.ConstantCheckState;
7605
7606                         ec.CheckState = true;
7607                         ec.ConstantCheckState = true;
7608                         Expr.Emit (ec);
7609                         ec.CheckState = last_check;
7610                         ec.ConstantCheckState = last_const_check;
7611                 }
7612
7613         }
7614
7615         /// <summary>
7616         ///   Implements the unchecked expression
7617         /// </summary>
7618         public class UnCheckedExpr : Expression {
7619
7620                 public Expression Expr;
7621
7622                 public UnCheckedExpr (Expression e, Location l)
7623                 {
7624                         Expr = e;
7625                         loc = l;
7626                 }
7627
7628                 public override Expression DoResolve (EmitContext ec)
7629                 {
7630                         bool last_check = ec.CheckState;
7631                         bool last_const_check = ec.ConstantCheckState;
7632
7633                         ec.CheckState = false;
7634                         ec.ConstantCheckState = false;
7635                         Expr = Expr.Resolve (ec);
7636                         ec.CheckState = last_check;
7637                         ec.ConstantCheckState = last_const_check;
7638
7639                         if (Expr == null)
7640                                 return null;
7641
7642                         if (Expr is Constant)
7643                                 return Expr;
7644
7645                         eclass = Expr.eclass;
7646                         type = Expr.Type;
7647                         return this;
7648                 }
7649
7650                 public override void Emit (EmitContext ec)
7651                 {
7652                         bool last_check = ec.CheckState;
7653                         bool last_const_check = ec.ConstantCheckState;
7654
7655                         ec.CheckState = false;
7656                         ec.ConstantCheckState = false;
7657                         Expr.Emit (ec);
7658                         ec.CheckState = last_check;
7659                         ec.ConstantCheckState = last_const_check;
7660                 }
7661
7662         }
7663
7664         /// <summary>
7665         ///   An Element Access expression.
7666         ///
7667         ///   During semantic analysis these are transformed into
7668         ///   IndexerAccess, ArrayAccess or a PointerArithmetic.
7669         /// </summary>
7670         public class ElementAccess : Expression {
7671                 public ArrayList  Arguments;
7672                 public Expression Expr;
7673
7674                 public ElementAccess (Expression e, ArrayList e_list, Location l)
7675                 {
7676                         Expr = e;
7677
7678                         loc  = l;
7679
7680                         if (e_list == null)
7681                                 return;
7682
7683                         Arguments = new ArrayList ();
7684                         foreach (Expression tmp in e_list)
7685                                 Arguments.Add (new Argument (tmp, Argument.AType.Expression));
7686
7687                 }
7688
7689                 bool CommonResolve (EmitContext ec)
7690                 {
7691                         Expr = Expr.Resolve (ec);
7692
7693                         if (Expr == null)
7694                                 return false;
7695
7696                         if (Arguments == null)
7697                                 return false;
7698
7699                         foreach (Argument a in Arguments){
7700                                 if (!a.Resolve (ec, loc))
7701                                         return false;
7702                         }
7703
7704                         return true;
7705                 }
7706
7707                 Expression MakePointerAccess (EmitContext ec, Type t)
7708                 {
7709                         if (t == TypeManager.void_ptr_type){
7710                                 Error (242, "The array index operation is not valid for void pointers");
7711                                 return null;
7712                         }
7713                         if (Arguments.Count != 1){
7714                                 Error (196, "A pointer must be indexed by a single value");
7715                                 return null;
7716                         }
7717                         Expression p;
7718
7719                         p = new PointerArithmetic (true, Expr, ((Argument)Arguments [0]).Expr, t, loc).Resolve (ec);
7720                         if (p == null)
7721                                 return null;
7722                         return new Indirection (p, loc).Resolve (ec);
7723                 }
7724
7725                 public override Expression DoResolve (EmitContext ec)
7726                 {
7727                         if (!CommonResolve (ec))
7728                                 return null;
7729
7730                         //
7731                         // We perform some simple tests, and then to "split" the emit and store
7732                         // code we create an instance of a different class, and return that.
7733                         //
7734                         // I am experimenting with this pattern.
7735                         //
7736                         Type t = Expr.Type;
7737
7738                         if (t == TypeManager.array_type){
7739                                 Report.Error (21, loc, "Cannot use indexer on System.Array");
7740                                 return null;
7741                         }
7742
7743                         if (t.IsArray)
7744                                 return (new ArrayAccess (this, loc)).Resolve (ec);
7745                         if (t.IsPointer)
7746                                 return MakePointerAccess (ec, Expr.Type);
7747
7748                         FieldExpr fe = Expr as FieldExpr;
7749                         if (fe != null) {
7750                                 IFixedBuffer ff = AttributeTester.GetFixedBuffer (fe.FieldInfo);
7751                                 if (ff != null) {
7752                                         return MakePointerAccess (ec, ff.ElementType);
7753                                 }
7754                         }
7755                         return (new IndexerAccess (this, loc)).Resolve (ec);
7756                 }
7757
7758                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
7759                 {
7760                         if (!CommonResolve (ec))
7761                                 return null;
7762
7763                         Type t = Expr.Type;
7764                         if (t.IsArray)
7765                                 return (new ArrayAccess (this, loc)).ResolveLValue (ec, right_side);
7766
7767                         if (t.IsPointer)
7768                                 return MakePointerAccess (ec, Expr.Type);
7769
7770                         FieldExpr fe = Expr as FieldExpr;
7771                         if (fe != null) {
7772                                 IFixedBuffer ff = AttributeTester.GetFixedBuffer (fe.FieldInfo);
7773                                 if (ff != null) {
7774                                         if (!(fe.InstanceExpression is LocalVariableReference) &&
7775                                                 !(fe.InstanceExpression is This)) {
7776                                                 Error (1708, "Fixed buffers can only be accessed through locals or fields");
7777                                                 return null;
7778                                         }
7779 // TODO: not sure whether it is correct
7780 //                                      if (!ec.InFixedInitializer) {
7781 //                                              Error (1666, "You cannot use fixed sized buffers contained in unfixed expressions. Try using the fixed statement");
7782 //                                              return null;
7783 //                                      }
7784                                         return MakePointerAccess (ec, ff.ElementType);
7785                                 }
7786                         }
7787                         return (new IndexerAccess (this, loc)).ResolveLValue (ec, right_side);
7788                 }
7789
7790                 public override void Emit (EmitContext ec)
7791                 {
7792                         throw new Exception ("Should never be reached");
7793                 }
7794         }
7795
7796         /// <summary>
7797         ///   Implements array access
7798         /// </summary>
7799         public class ArrayAccess : Expression, IAssignMethod, IMemoryLocation {
7800                 //
7801                 // Points to our "data" repository
7802                 //
7803                 ElementAccess ea;
7804
7805                 LocalTemporary temp;
7806                 bool prepared;
7807
7808                 public ArrayAccess (ElementAccess ea_data, Location l)
7809                 {
7810                         ea = ea_data;
7811                         eclass = ExprClass.Variable;
7812                         loc = l;
7813                 }
7814
7815                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
7816                 {
7817                         return DoResolve (ec);
7818                 }
7819
7820                 public override Expression DoResolve (EmitContext ec)
7821                 {
7822 #if false
7823                         ExprClass eclass = ea.Expr.eclass;
7824
7825                         // As long as the type is valid
7826                         if (!(eclass == ExprClass.Variable || eclass == ExprClass.PropertyAccess ||
7827                               eclass == ExprClass.Value)) {
7828                                 ea.Expr.Error_UnexpectedKind ("variable or value");
7829                                 return null;
7830                         }
7831 #endif
7832
7833                         Type t = ea.Expr.Type;
7834                         if (t.GetArrayRank () != ea.Arguments.Count){
7835                                 ea.Error (22,
7836                                           "Incorrect number of indexes for array " +
7837                                           " expected: " + t.GetArrayRank () + " got: " +
7838                                           ea.Arguments.Count);
7839                                 return null;
7840                         }
7841
7842                         type = TypeManager.GetElementType (t);
7843                         if (type.IsPointer && !ec.InUnsafe){
7844                                 UnsafeError (ea.Location);
7845                                 return null;
7846                         }
7847
7848                         foreach (Argument a in ea.Arguments){
7849                                 Type argtype = a.Type;
7850
7851                                 if (argtype == TypeManager.int32_type ||
7852                                     argtype == TypeManager.uint32_type ||
7853                                     argtype == TypeManager.int64_type ||
7854                                     argtype == TypeManager.uint64_type) {
7855                                         Constant c = a.Expr as Constant;
7856                                         if (c != null && c.IsNegative) {
7857                                                 Report.Warning (251, 2, a.Expr.Location, "Indexing an array with a negative index (array indices always start at zero)");
7858                                         }
7859                                         continue;
7860                                 }
7861
7862                                 //
7863                                 // Mhm.  This is strage, because the Argument.Type is not the same as
7864                                 // Argument.Expr.Type: the value changes depending on the ref/out setting.
7865                                 //
7866                                 // Wonder if I will run into trouble for this.
7867                                 //
7868                                 a.Expr = ExpressionToArrayArgument (ec, a.Expr, ea.Location);
7869                                 if (a.Expr == null)
7870                                         return null;
7871                         }
7872
7873                         eclass = ExprClass.Variable;
7874
7875                         return this;
7876                 }
7877
7878                 /// <summary>
7879                 ///    Emits the right opcode to load an object of Type `t'
7880                 ///    from an array of T
7881                 /// </summary>
7882                 static public void EmitLoadOpcode (ILGenerator ig, Type type)
7883                 {
7884                         if (type == TypeManager.byte_type || type == TypeManager.bool_type)
7885                                 ig.Emit (OpCodes.Ldelem_U1);
7886                         else if (type == TypeManager.sbyte_type)
7887                                 ig.Emit (OpCodes.Ldelem_I1);
7888                         else if (type == TypeManager.short_type)
7889                                 ig.Emit (OpCodes.Ldelem_I2);
7890                         else if (type == TypeManager.ushort_type || type == TypeManager.char_type)
7891                                 ig.Emit (OpCodes.Ldelem_U2);
7892                         else if (type == TypeManager.int32_type)
7893                                 ig.Emit (OpCodes.Ldelem_I4);
7894                         else if (type == TypeManager.uint32_type)
7895                                 ig.Emit (OpCodes.Ldelem_U4);
7896                         else if (type == TypeManager.uint64_type)
7897                                 ig.Emit (OpCodes.Ldelem_I8);
7898                         else if (type == TypeManager.int64_type)
7899                                 ig.Emit (OpCodes.Ldelem_I8);
7900                         else if (type == TypeManager.float_type)
7901                                 ig.Emit (OpCodes.Ldelem_R4);
7902                         else if (type == TypeManager.double_type)
7903                                 ig.Emit (OpCodes.Ldelem_R8);
7904                         else if (type == TypeManager.intptr_type)
7905                                 ig.Emit (OpCodes.Ldelem_I);
7906                         else if (TypeManager.IsEnumType (type)){
7907                                 EmitLoadOpcode (ig, TypeManager.EnumToUnderlying (type));
7908                         } else if (type.IsValueType){
7909                                 ig.Emit (OpCodes.Ldelema, type);
7910                                 ig.Emit (OpCodes.Ldobj, type);
7911                         } else if (type.IsGenericParameter)
7912                                 ig.Emit (OpCodes.Ldelem_Any, type);
7913                         else
7914                                 ig.Emit (OpCodes.Ldelem_Ref);
7915                 }
7916
7917                 /// <summary>
7918                 ///    Returns the right opcode to store an object of Type `t'
7919                 ///    from an array of T.
7920                 /// </summary>
7921                 static public OpCode GetStoreOpcode (Type t, out bool is_stobj, out bool has_type_arg)
7922                 {
7923                         //Console.WriteLine (new System.Diagnostics.StackTrace ());
7924                         has_type_arg = false; is_stobj = false;
7925                         t = TypeManager.TypeToCoreType (t);
7926                         if (TypeManager.IsEnumType (t))
7927                                 t = TypeManager.EnumToUnderlying (t);
7928                         if (t == TypeManager.byte_type || t == TypeManager.sbyte_type ||
7929                             t == TypeManager.bool_type)
7930                                 return OpCodes.Stelem_I1;
7931                         else if (t == TypeManager.short_type || t == TypeManager.ushort_type ||
7932                                  t == TypeManager.char_type)
7933                                 return OpCodes.Stelem_I2;
7934                         else if (t == TypeManager.int32_type || t == TypeManager.uint32_type)
7935                                 return OpCodes.Stelem_I4;
7936                         else if (t == TypeManager.int64_type || t == TypeManager.uint64_type)
7937                                 return OpCodes.Stelem_I8;
7938                         else if (t == TypeManager.float_type)
7939                                 return OpCodes.Stelem_R4;
7940                         else if (t == TypeManager.double_type)
7941                                 return OpCodes.Stelem_R8;
7942                         else if (t == TypeManager.intptr_type) {
7943                                 has_type_arg = true;
7944                                 is_stobj = true;
7945                                 return OpCodes.Stobj;
7946                         } else if (t.IsValueType) {
7947                                 has_type_arg = true;
7948                                 is_stobj = true;
7949                                 return OpCodes.Stobj;
7950                         } else if (t.IsGenericParameter) {
7951                                 has_type_arg = true;
7952                                 return OpCodes.Stelem_Any;
7953                         } else
7954                                 return OpCodes.Stelem_Ref;
7955                 }
7956
7957                 MethodInfo FetchGetMethod ()
7958                 {
7959                         ModuleBuilder mb = CodeGen.Module.Builder;
7960                         int arg_count = ea.Arguments.Count;
7961                         Type [] args = new Type [arg_count];
7962                         MethodInfo get;
7963
7964                         for (int i = 0; i < arg_count; i++){
7965                                 //args [i++] = a.Type;
7966                                 args [i] = TypeManager.int32_type;
7967                         }
7968
7969                         get = mb.GetArrayMethod (
7970                                 ea.Expr.Type, "Get",
7971                                 CallingConventions.HasThis |
7972                                 CallingConventions.Standard,
7973                                 type, args);
7974                         return get;
7975                 }
7976
7977
7978                 MethodInfo FetchAddressMethod ()
7979                 {
7980                         ModuleBuilder mb = CodeGen.Module.Builder;
7981                         int arg_count = ea.Arguments.Count;
7982                         Type [] args = new Type [arg_count];
7983                         MethodInfo address;
7984                         Type ret_type;
7985
7986                         ret_type = TypeManager.GetReferenceType (type);
7987
7988                         for (int i = 0; i < arg_count; i++){
7989                                 //args [i++] = a.Type;
7990                                 args [i] = TypeManager.int32_type;
7991                         }
7992
7993                         address = mb.GetArrayMethod (
7994                                 ea.Expr.Type, "Address",
7995                                 CallingConventions.HasThis |
7996                                 CallingConventions.Standard,
7997                                 ret_type, args);
7998
7999                         return address;
8000                 }
8001
8002                 //
8003                 // Load the array arguments into the stack.
8004                 //
8005                 // If we have been requested to cache the values (cached_locations array
8006                 // initialized), then load the arguments the first time and store them
8007                 // in locals.  otherwise load from local variables.
8008                 //
8009                 void LoadArrayAndArguments (EmitContext ec)
8010                 {
8011                         ILGenerator ig = ec.ig;
8012
8013                         ea.Expr.Emit (ec);
8014                         foreach (Argument a in ea.Arguments){
8015                                 Type argtype = a.Expr.Type;
8016
8017                                 a.Expr.Emit (ec);
8018
8019                                 if (argtype == TypeManager.int64_type)
8020                                         ig.Emit (OpCodes.Conv_Ovf_I);
8021                                 else if (argtype == TypeManager.uint64_type)
8022                                         ig.Emit (OpCodes.Conv_Ovf_I_Un);
8023                         }
8024                 }
8025
8026                 public void Emit (EmitContext ec, bool leave_copy)
8027                 {
8028                         int rank = ea.Expr.Type.GetArrayRank ();
8029                         ILGenerator ig = ec.ig;
8030
8031                         if (!prepared) {
8032                                 LoadArrayAndArguments (ec);
8033
8034                                 if (rank == 1)
8035                                         EmitLoadOpcode (ig, type);
8036                                 else {
8037                                         MethodInfo method;
8038
8039                                         method = FetchGetMethod ();
8040                                         ig.Emit (OpCodes.Call, method);
8041                                 }
8042                         } else
8043                                 LoadFromPtr (ec.ig, this.type);
8044
8045                         if (leave_copy) {
8046                                 ec.ig.Emit (OpCodes.Dup);
8047                                 temp = new LocalTemporary (ec, this.type);
8048                                 temp.Store (ec);
8049                         }
8050                 }
8051
8052                 public override void Emit (EmitContext ec)
8053                 {
8054                         Emit (ec, false);
8055                 }
8056
8057                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
8058                 {
8059                         int rank = ea.Expr.Type.GetArrayRank ();
8060                         ILGenerator ig = ec.ig;
8061                         Type t = source.Type;
8062                         prepared = prepare_for_load;
8063
8064                         if (prepare_for_load) {
8065                                 AddressOf (ec, AddressOp.LoadStore);
8066                                 ec.ig.Emit (OpCodes.Dup);
8067                                 source.Emit (ec);
8068                                 if (leave_copy) {
8069                                         ec.ig.Emit (OpCodes.Dup);
8070                                         temp = new LocalTemporary (ec, this.type);
8071                                         temp.Store (ec);
8072                                 }
8073                                 StoreFromPtr (ec.ig, t);
8074
8075                                 if (temp != null)
8076                                         temp.Emit (ec);
8077
8078                                 return;
8079                         }
8080
8081                         LoadArrayAndArguments (ec);
8082
8083                         if (rank == 1) {
8084                                 bool is_stobj, has_type_arg;
8085                                 OpCode op = GetStoreOpcode (t, out is_stobj, out has_type_arg);
8086
8087                                 //
8088                                 // The stobj opcode used by value types will need
8089                                 // an address on the stack, not really an array/array
8090                                 // pair
8091                                 //
8092                                 if (is_stobj)
8093                                         ig.Emit (OpCodes.Ldelema, t);
8094
8095                                 source.Emit (ec);
8096                                 if (leave_copy) {
8097                                         ec.ig.Emit (OpCodes.Dup);
8098                                         temp = new LocalTemporary (ec, this.type);
8099                                         temp.Store (ec);
8100                                 }
8101
8102                                 if (is_stobj)
8103                                         ig.Emit (OpCodes.Stobj, t);
8104                                 else if (has_type_arg)
8105                                         ig.Emit (op, t);
8106                                 else
8107                                         ig.Emit (op);
8108                         } else {
8109                                 ModuleBuilder mb = CodeGen.Module.Builder;
8110                                 int arg_count = ea.Arguments.Count;
8111                                 Type [] args = new Type [arg_count + 1];
8112                                 MethodInfo set;
8113
8114                                 source.Emit (ec);
8115                                 if (leave_copy) {
8116                                         ec.ig.Emit (OpCodes.Dup);
8117                                         temp = new LocalTemporary (ec, this.type);
8118                                         temp.Store (ec);
8119                                 }
8120
8121                                 for (int i = 0; i < arg_count; i++){
8122                                         //args [i++] = a.Type;
8123                                         args [i] = TypeManager.int32_type;
8124                                 }
8125
8126                                 args [arg_count] = type;
8127
8128                                 set = mb.GetArrayMethod (
8129                                         ea.Expr.Type, "Set",
8130                                         CallingConventions.HasThis |
8131                                         CallingConventions.Standard,
8132                                         TypeManager.void_type, args);
8133
8134                                 ig.Emit (OpCodes.Call, set);
8135                         }
8136
8137                         if (temp != null)
8138                                 temp.Emit (ec);
8139                 }
8140
8141                 public void AddressOf (EmitContext ec, AddressOp mode)
8142                 {
8143                         int rank = ea.Expr.Type.GetArrayRank ();
8144                         ILGenerator ig = ec.ig;
8145
8146                         LoadArrayAndArguments (ec);
8147
8148                         if (rank == 1){
8149                                 ig.Emit (OpCodes.Ldelema, type);
8150                         } else {
8151                                 MethodInfo address = FetchAddressMethod ();
8152                                 ig.Emit (OpCodes.Call, address);
8153                         }
8154                 }
8155         }
8156
8157
8158         class Indexers {
8159                 public ArrayList Properties;
8160                 static Hashtable map;
8161
8162                 public struct Indexer {
8163                         public readonly Type Type;
8164                         public readonly MethodInfo Getter, Setter;
8165
8166                         public Indexer (Type type, MethodInfo get, MethodInfo set)
8167                         {
8168                                 this.Type = type;
8169                                 this.Getter = get;
8170                                 this.Setter = set;
8171                         }
8172                 }
8173
8174                 static Indexers ()
8175                 {
8176                         map = new Hashtable ();
8177                 }
8178
8179                 Indexers ()
8180                 {
8181                         Properties = new ArrayList ();
8182                 }
8183
8184                 void Append (MemberInfo [] mi)
8185                 {
8186                         foreach (PropertyInfo property in mi){
8187                                 MethodInfo get, set;
8188
8189                                 get = property.GetGetMethod (true);
8190                                 set = property.GetSetMethod (true);
8191                                 Properties.Add (new Indexer (property.PropertyType, get, set));
8192                         }
8193                 }
8194
8195                 static private MemberInfo [] GetIndexersForTypeOrInterface (Type caller_type, Type lookup_type)
8196                 {
8197                         string p_name = TypeManager.IndexerPropertyName (lookup_type);
8198
8199                         MemberInfo [] mi = TypeManager.MemberLookup (
8200                                 caller_type, caller_type, lookup_type, MemberTypes.Property,
8201                                 BindingFlags.Public | BindingFlags.Instance |
8202                                 BindingFlags.DeclaredOnly, p_name, null);
8203
8204                         if (mi == null || mi.Length == 0)
8205                                 return null;
8206
8207                         return mi;
8208                 }
8209
8210                 static public Indexers GetIndexersForType (Type caller_type, Type lookup_type, Location loc)
8211                 {
8212                         Indexers ix = (Indexers) map [lookup_type];
8213
8214                         if (ix != null)
8215                                 return ix;
8216
8217                         Type copy = lookup_type;
8218                         while (copy != TypeManager.object_type && copy != null){
8219                                 MemberInfo [] mi = GetIndexersForTypeOrInterface (caller_type, copy);
8220
8221                                 if (mi != null){
8222                                         if (ix == null)
8223                                                 ix = new Indexers ();
8224
8225                                         ix.Append (mi);
8226                                 }
8227
8228                                 copy = copy.BaseType;
8229                         }
8230
8231                         if (!lookup_type.IsInterface)
8232                                 return ix;
8233
8234                         Type [] ifaces = TypeManager.GetInterfaces (lookup_type);
8235                         if (ifaces != null) {
8236                                 foreach (Type itype in ifaces) {
8237                                         MemberInfo [] mi = GetIndexersForTypeOrInterface (caller_type, itype);
8238                                         if (mi != null){
8239                                                 if (ix == null)
8240                                                         ix = new Indexers ();
8241
8242                                                 ix.Append (mi);
8243                                         }
8244                                 }
8245                         }
8246
8247                         return ix;
8248                 }
8249         }
8250
8251         /// <summary>
8252         ///   Expressions that represent an indexer call.
8253         /// </summary>
8254         public class IndexerAccess : Expression, IAssignMethod {
8255                 //
8256                 // Points to our "data" repository
8257                 //
8258                 MethodInfo get, set;
8259                 ArrayList set_arguments;
8260                 bool is_base_indexer;
8261
8262                 protected Type indexer_type;
8263                 protected Type current_type;
8264                 protected Expression instance_expr;
8265                 protected ArrayList arguments;
8266
8267                 public IndexerAccess (ElementAccess ea, Location loc)
8268                         : this (ea.Expr, false, loc)
8269                 {
8270                         this.arguments = ea.Arguments;
8271                 }
8272
8273                 protected IndexerAccess (Expression instance_expr, bool is_base_indexer,
8274                                          Location loc)
8275                 {
8276                         this.instance_expr = instance_expr;
8277                         this.is_base_indexer = is_base_indexer;
8278                         this.eclass = ExprClass.Value;
8279                         this.loc = loc;
8280                 }
8281
8282                 protected virtual bool CommonResolve (EmitContext ec)
8283                 {
8284                         indexer_type = instance_expr.Type;
8285                         current_type = ec.ContainerType;
8286
8287                         return true;
8288                 }
8289
8290                 public override Expression DoResolve (EmitContext ec)
8291                 {
8292                         ArrayList AllGetters = new ArrayList();
8293                         if (!CommonResolve (ec))
8294                                 return null;
8295
8296                         //
8297                         // Step 1: Query for all `Item' *properties*.  Notice
8298                         // that the actual methods are pointed from here.
8299                         //
8300                         // This is a group of properties, piles of them.
8301
8302                         bool found_any = false, found_any_getters = false;
8303                         Type lookup_type = indexer_type;
8304
8305                         Indexers ilist;
8306                         ilist = Indexers.GetIndexersForType (current_type, lookup_type, loc);
8307                         if (ilist != null) {
8308                                 found_any = true;
8309                                 if (ilist.Properties != null) {
8310                                         foreach (Indexers.Indexer ix in ilist.Properties) {
8311                                                 if (ix.Getter != null)
8312                                                         AllGetters.Add(ix.Getter);
8313                                         }
8314                                 }
8315                         }
8316
8317                         if (AllGetters.Count > 0) {
8318                                 found_any_getters = true;
8319                                 get = (MethodInfo) Invocation.OverloadResolve (
8320                                         ec, new MethodGroupExpr (AllGetters, loc),
8321                                         arguments, false, loc);
8322                         }
8323
8324                         if (!found_any) {
8325                                 Report.Error (21, loc,
8326                                               "Type `" + TypeManager.CSharpName (indexer_type) +
8327                                               "' does not have any indexers defined");
8328                                 return null;
8329                         }
8330
8331                         if (!found_any_getters) {
8332                                 Error (154, "indexer can not be used in this context, because " +
8333                                        "it lacks a `get' accessor");
8334                                 return null;
8335                         }
8336
8337                         if (get == null) {
8338                                 Error (1501, "No Overload for method `this' takes `" +
8339                                        arguments.Count + "' arguments");
8340                                 return null;
8341                         }
8342
8343                         //
8344                         // Only base will allow this invocation to happen.
8345                         //
8346                         if (get.IsAbstract && this is BaseIndexerAccess){
8347                                 Report.Error (205, loc, "Cannot call an abstract base indexer: " + Invocation.FullMethodDesc (get));
8348                                 return null;
8349                         }
8350
8351                         type = get.ReturnType;
8352                         if (type.IsPointer && !ec.InUnsafe){
8353                                 UnsafeError (loc);
8354                                 return null;
8355                         }
8356
8357                         instance_expr.CheckMarshallByRefAccess (ec.ContainerType);
8358
8359                         eclass = ExprClass.IndexerAccess;
8360                         return this;
8361                 }
8362
8363                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
8364                 {
8365                         ArrayList AllSetters = new ArrayList();
8366                         if (!CommonResolve (ec))
8367                                 return null;
8368
8369                         bool found_any = false, found_any_setters = false;
8370
8371                         Indexers ilist = Indexers.GetIndexersForType (current_type, indexer_type, loc);
8372                         if (ilist != null) {
8373                                 found_any = true;
8374                                 if (ilist.Properties != null) {
8375                                         foreach (Indexers.Indexer ix in ilist.Properties) {
8376                                                 if (ix.Setter != null)
8377                                                         AllSetters.Add(ix.Setter);
8378                                         }
8379                                 }
8380                         }
8381                         if (AllSetters.Count > 0) {
8382                                 found_any_setters = true;
8383                                 set_arguments = (ArrayList) arguments.Clone ();
8384                                 set_arguments.Add (new Argument (right_side, Argument.AType.Expression));
8385                                 set = (MethodInfo) Invocation.OverloadResolve (
8386                                         ec, new MethodGroupExpr (AllSetters, loc),
8387                                         set_arguments, false, loc);
8388                         }
8389
8390                         if (!found_any) {
8391                                 Report.Error (21, loc,
8392                                               "Type `" + TypeManager.CSharpName (indexer_type) +
8393                                               "' does not have any indexers defined");
8394                                 return null;
8395                         }
8396
8397                         if (!found_any_setters) {
8398                                 Error (154, "indexer can not be used in this context, because " +
8399                                        "it lacks a `set' accessor");
8400                                 return null;
8401                         }
8402
8403                         if (set == null) {
8404                                 Error (1501, "No Overload for method `this' takes `" +
8405                                        arguments.Count + "' arguments");
8406                                 return null;
8407                         }
8408
8409                         //
8410                         // Only base will allow this invocation to happen.
8411                         //
8412                         if (set.IsAbstract && this is BaseIndexerAccess){
8413                                 Report.Error (205, loc, "Cannot call an abstract base indexer: " + Invocation.FullMethodDesc (set));
8414                                 return null;
8415                         }
8416
8417                         //
8418                         // Now look for the actual match in the list of indexers to set our "return" type
8419                         //
8420                         type = TypeManager.void_type;   // default value
8421                         foreach (Indexers.Indexer ix in ilist.Properties){
8422                                 if (ix.Setter == set){
8423                                         type = ix.Type;
8424                                         break;
8425                                 }
8426                         }
8427
8428                         instance_expr.CheckMarshallByRefAccess (ec.ContainerType);
8429
8430                         eclass = ExprClass.IndexerAccess;
8431                         return this;
8432                 }
8433
8434                 bool prepared = false;
8435                 LocalTemporary temp;
8436
8437                 public void Emit (EmitContext ec, bool leave_copy)
8438                 {
8439                         Invocation.EmitCall (ec, is_base_indexer, false, instance_expr, get, arguments, loc, prepared, false);
8440                         if (leave_copy) {
8441                                 ec.ig.Emit (OpCodes.Dup);
8442                                 temp = new LocalTemporary (ec, Type);
8443                                 temp.Store (ec);
8444                         }
8445                 }
8446
8447                 //
8448                 // source is ignored, because we already have a copy of it from the
8449                 // LValue resolution and we have already constructed a pre-cached
8450                 // version of the arguments (ea.set_arguments);
8451                 //
8452                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
8453                 {
8454                         prepared = prepare_for_load;
8455                         Argument a = (Argument) set_arguments [set_arguments.Count - 1];
8456
8457                         if (prepared) {
8458                                 source.Emit (ec);
8459                                 if (leave_copy) {
8460                                         ec.ig.Emit (OpCodes.Dup);
8461                                         temp = new LocalTemporary (ec, Type);
8462                                         temp.Store (ec);
8463                                 }
8464                         } else if (leave_copy) {
8465                                 temp = new LocalTemporary (ec, Type);
8466                                 source.Emit (ec);
8467                                 temp.Store (ec);
8468                                 a.Expr = temp;
8469                         }
8470
8471                         Invocation.EmitCall (ec, is_base_indexer, false, instance_expr, set, set_arguments, loc, false, prepared);
8472
8473                         if (temp != null)
8474                                 temp.Emit (ec);
8475                 }
8476
8477
8478                 public override void Emit (EmitContext ec)
8479                 {
8480                         Emit (ec, false);
8481                 }
8482         }
8483
8484         /// <summary>
8485         ///   The base operator for method names
8486         /// </summary>
8487         public class BaseAccess : Expression {
8488                 string member;
8489
8490                 public BaseAccess (string member, Location l)
8491                 {
8492                         this.member = member;
8493                         loc = l;
8494                 }
8495
8496                 public override Expression DoResolve (EmitContext ec)
8497                 {
8498                         Expression c = CommonResolve (ec);
8499
8500                         if (c == null)
8501                                 return null;
8502
8503                         //
8504                         // MethodGroups use this opportunity to flag an error on lacking ()
8505                         //
8506                         if (!(c is MethodGroupExpr))
8507                                 return c.Resolve (ec);
8508                         return c;
8509                 }
8510
8511                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
8512                 {
8513                         Expression c = CommonResolve (ec);
8514
8515                         if (c == null)
8516                                 return null;
8517
8518                         //
8519                         // MethodGroups use this opportunity to flag an error on lacking ()
8520                         //
8521                         if (! (c is MethodGroupExpr))
8522                                 return c.DoResolveLValue (ec, right_side);
8523
8524                         return c;
8525                 }
8526
8527                 Expression CommonResolve (EmitContext ec)
8528                 {
8529                         Expression member_lookup;
8530                         Type current_type = ec.ContainerType;
8531                         Type base_type = current_type.BaseType;
8532
8533                         if (ec.IsStatic){
8534                                 Error (1511, "Keyword base is not allowed in static method");
8535                                 return null;
8536                         }
8537
8538                         if (ec.IsFieldInitializer){
8539                                 Error (1512, "Keyword base is not available in the current context");
8540                                 return null;
8541                         }
8542
8543                         member_lookup = MemberLookup (ec, ec.ContainerType, null, base_type,
8544                                                       member, AllMemberTypes, AllBindingFlags,
8545                                                       loc);
8546                         if (member_lookup == null) {
8547                                 MemberLookupFailed (ec, base_type, base_type, member, null, true, loc);
8548                                 return null;
8549                         }
8550
8551                         Expression left;
8552
8553                         if (ec.IsStatic)
8554                                 left = new TypeExpression (base_type, loc);
8555                         else
8556                                 left = ec.GetThis (loc);
8557
8558                         MemberExpr me = (MemberExpr) member_lookup;
8559
8560                         Expression e = me.ResolveMemberAccess (ec, left, loc, null);
8561
8562                         if (e is PropertyExpr) {
8563                                 PropertyExpr pe = (PropertyExpr) e;
8564
8565                                 pe.IsBase = true;
8566                         }
8567
8568                         if (e is MethodGroupExpr)
8569                                 ((MethodGroupExpr) e).IsBase = true;
8570
8571                         return e;
8572                 }
8573
8574                 public override void Emit (EmitContext ec)
8575                 {
8576                         throw new Exception ("Should never be called");
8577                 }
8578         }
8579
8580         /// <summary>
8581         ///   The base indexer operator
8582         /// </summary>
8583         public class BaseIndexerAccess : IndexerAccess {
8584                 public BaseIndexerAccess (ArrayList args, Location loc)
8585                         : base (null, true, loc)
8586                 {
8587                         arguments = new ArrayList ();
8588                         foreach (Expression tmp in args)
8589                                 arguments.Add (new Argument (tmp, Argument.AType.Expression));
8590                 }
8591
8592                 protected override bool CommonResolve (EmitContext ec)
8593                 {
8594                         instance_expr = ec.GetThis (loc);
8595
8596                         current_type = ec.ContainerType.BaseType;
8597                         indexer_type = current_type;
8598
8599                         foreach (Argument a in arguments){
8600                                 if (!a.Resolve (ec, loc))
8601                                         return false;
8602                         }
8603
8604                         return true;
8605                 }
8606         }
8607
8608         /// <summary>
8609         ///   This class exists solely to pass the Type around and to be a dummy
8610         ///   that can be passed to the conversion functions (this is used by
8611         ///   foreach implementation to typecast the object return value from
8612         ///   get_Current into the proper type.  All code has been generated and
8613         ///   we only care about the side effect conversions to be performed
8614         ///
8615         ///   This is also now used as a placeholder where a no-action expression
8616         ///   is needed (the `New' class).
8617         /// </summary>
8618         public class EmptyExpression : Expression {
8619                 public static readonly EmptyExpression Null = new EmptyExpression ();
8620
8621                 // TODO: should be protected
8622                 public EmptyExpression ()
8623                 {
8624                         type = TypeManager.object_type;
8625                         eclass = ExprClass.Value;
8626                         loc = Location.Null;
8627                 }
8628
8629                 public EmptyExpression (Type t)
8630                 {
8631                         type = t;
8632                         eclass = ExprClass.Value;
8633                         loc = Location.Null;
8634                 }
8635
8636                 public override Expression DoResolve (EmitContext ec)
8637                 {
8638                         return this;
8639                 }
8640
8641                 public override void Emit (EmitContext ec)
8642                 {
8643                         // nothing, as we only exist to not do anything.
8644                 }
8645
8646                 //
8647                 // This is just because we might want to reuse this bad boy
8648                 // instead of creating gazillions of EmptyExpressions.
8649                 // (CanImplicitConversion uses it)
8650                 //
8651                 public void SetType (Type t)
8652                 {
8653                         type = t;
8654                 }
8655         }
8656
8657         public class UserCast : Expression {
8658                 MethodBase method;
8659                 Expression source;
8660
8661                 public UserCast (MethodInfo method, Expression source, Location l)
8662                 {
8663                         this.method = method;
8664                         this.source = source;
8665                         type = method.ReturnType;
8666                         eclass = ExprClass.Value;
8667                         loc = l;
8668                 }
8669
8670                 public Expression Source {
8671                         get {
8672                                 return source;
8673                         }
8674                 }
8675
8676                 public override Expression DoResolve (EmitContext ec)
8677                 {
8678                         //
8679                         // We are born fully resolved
8680                         //
8681                         return this;
8682                 }
8683
8684                 public override void Emit (EmitContext ec)
8685                 {
8686                         ILGenerator ig = ec.ig;
8687
8688                         source.Emit (ec);
8689
8690                         if (method is MethodInfo)
8691                                 ig.Emit (OpCodes.Call, (MethodInfo) method);
8692                         else
8693                                 ig.Emit (OpCodes.Call, (ConstructorInfo) method);
8694
8695                 }
8696         }
8697
8698         // <summary>
8699         //   This class is used to "construct" the type during a typecast
8700         //   operation.  Since the Type.GetType class in .NET can parse
8701         //   the type specification, we just use this to construct the type
8702         //   one bit at a time.
8703         // </summary>
8704         public class ComposedCast : TypeExpr {
8705                 Expression left;
8706                 string dim;
8707
8708                 public ComposedCast (Expression left, string dim, Location l)
8709                 {
8710                         this.left = left;
8711                         this.dim = dim;
8712                         loc = l;
8713                 }
8714
8715                 protected override TypeExpr DoResolveAsTypeStep (EmitContext ec)
8716                 {
8717                         TypeExpr lexpr = left.ResolveAsTypeTerminal (ec);
8718                         if (lexpr == null)
8719                                 return null;
8720
8721                         Type ltype = lexpr.Type;
8722
8723                         if ((ltype == TypeManager.void_type) && (dim != "*")) {
8724                                 Report.Error (1547, Location,
8725                                               "Keyword 'void' cannot be used in this context");
8726                                 return null;
8727                         }
8728
8729                         if ((dim.Length > 0) && (dim [0] == '?')) {
8730                                 TypeExpr nullable = new NullableType (left, loc);
8731                                 if (dim.Length > 1)
8732                                         nullable = new ComposedCast (nullable, dim.Substring (1), loc);
8733                                 return nullable.ResolveAsTypeTerminal (ec);
8734                         }
8735
8736                         if (dim == "*" && !TypeManager.IsUnmanagedType (ltype)) {
8737                                 Report.Error (208, loc, "Cannot declare a pointer to a managed type ('{0}')", ltype);
8738                                 return null;
8739                         }
8740
8741                         if (dim != "")
8742                                 type = TypeManager.GetConstructedType (ltype, dim);
8743                         else
8744                                 type = ltype;
8745
8746                         if (type == null) {
8747                                 throw new InternalErrorException ("Couldn't create computed type " + ltype + dim);
8748                         }
8749
8750                         if (!ec.InUnsafe && type.IsPointer){
8751                                 UnsafeError (loc);
8752                                 return null;
8753                         }
8754
8755                         if (type.IsArray && (type.GetElementType () == TypeManager.arg_iterator_type ||
8756                                 type.GetElementType () == TypeManager.typed_reference_type)) {
8757                                 Report.Error (611, loc, "Array elements cannot be of type '{0}'", TypeManager.CSharpName (type.GetElementType ()));
8758                                 return null;
8759                         }
8760
8761                         eclass = ExprClass.Type;
8762                         return this;
8763                 }
8764
8765                 public override string Name {
8766                         get {
8767                                 return left + dim;
8768                         }
8769                 }
8770
8771                 public override string FullName {
8772                         get {
8773                                 return type.FullName;
8774                         }
8775                 }
8776         }
8777
8778         public class FixedBufferPtr: Expression {
8779                 Expression array;
8780
8781                 public FixedBufferPtr (Expression array, Type array_type, Location l)
8782                 {
8783                         this.array = array;
8784                         this.loc = l;
8785
8786                         type = TypeManager.GetPointerType (array_type);
8787                         eclass = ExprClass.Value;
8788                 }
8789
8790                 public override void Emit(EmitContext ec)
8791                 {
8792                         array.Emit (ec);
8793                 }
8794
8795                 public override Expression DoResolve (EmitContext ec)
8796                 {
8797                         //
8798                         // We are born fully resolved
8799                         //
8800                         return this;
8801                 }
8802         }
8803
8804
8805         //
8806         // This class is used to represent the address of an array, used
8807         // only by the Fixed statement, this generates "&a [0]" construct
8808         // for fixed (char *pa = a)
8809         //
8810         public class ArrayPtr : FixedBufferPtr {
8811                 Type array_type;
8812
8813                 public ArrayPtr (Expression array, Type array_type, Location l):
8814                         base (array, array_type, l)
8815                 {
8816                         this.array_type = array_type;
8817                 }
8818
8819                 public override void Emit (EmitContext ec)
8820                 {
8821                         base.Emit (ec);
8822
8823                         ILGenerator ig = ec.ig;
8824                         IntLiteral.EmitInt (ig, 0);
8825                         ig.Emit (OpCodes.Ldelema, array_type);
8826                 }
8827         }
8828
8829         //
8830         // Used by the fixed statement
8831         //
8832         public class StringPtr : Expression {
8833                 LocalBuilder b;
8834
8835                 public StringPtr (LocalBuilder b, Location l)
8836                 {
8837                         this.b = b;
8838                         eclass = ExprClass.Value;
8839                         type = TypeManager.char_ptr_type;
8840                         loc = l;
8841                 }
8842
8843                 public override Expression DoResolve (EmitContext ec)
8844                 {
8845                         // This should never be invoked, we are born in fully
8846                         // initialized state.
8847
8848                         return this;
8849                 }
8850
8851                 public override void Emit (EmitContext ec)
8852                 {
8853                         ILGenerator ig = ec.ig;
8854
8855                         ig.Emit (OpCodes.Ldloc, b);
8856                         ig.Emit (OpCodes.Conv_I);
8857                         ig.Emit (OpCodes.Call, TypeManager.int_get_offset_to_string_data);
8858                         ig.Emit (OpCodes.Add);
8859                 }
8860         }
8861
8862         //
8863         // Implements the `stackalloc' keyword
8864         //
8865         public class StackAlloc : Expression {
8866                 Type otype;
8867                 Expression t;
8868                 Expression count;
8869
8870                 public StackAlloc (Expression type, Expression count, Location l)
8871                 {
8872                         t = type;
8873                         this.count = count;
8874                         loc = l;
8875                 }
8876
8877                 public override Expression DoResolve (EmitContext ec)
8878                 {
8879                         count = count.Resolve (ec);
8880                         if (count == null)
8881                                 return null;
8882
8883                         if (count.Type != TypeManager.int32_type){
8884                                 count = Convert.ImplicitConversionRequired (ec, count, TypeManager.int32_type, loc);
8885                                 if (count == null)
8886                                         return null;
8887                         }
8888
8889                         Constant c = count as Constant;
8890                         if (c != null && c.IsNegative) {
8891                                 Report.Error (247, loc, "Cannot use a negative size with stackalloc");
8892                                 return null;
8893                         }
8894
8895                         if (ec.InCatch || ec.InFinally) {
8896                                 Error (255,
8897                                               "stackalloc can not be used in a catch or finally block");
8898                                 return null;
8899                         }
8900
8901                         TypeExpr texpr = t.ResolveAsTypeTerminal (ec);
8902                         if (texpr == null)
8903                                 return null;
8904
8905                         otype = texpr.Type;
8906
8907                         if (!TypeManager.VerifyUnManaged (otype, loc))
8908                                 return null;
8909
8910                         type = TypeManager.GetPointerType (otype);
8911                         eclass = ExprClass.Value;
8912
8913                         return this;
8914                 }
8915
8916                 public override void Emit (EmitContext ec)
8917                 {
8918                         int size = GetTypeSize (otype);
8919                         ILGenerator ig = ec.ig;
8920
8921                         if (size == 0)
8922                                 ig.Emit (OpCodes.Sizeof, otype);
8923                         else
8924                                 IntConstant.EmitInt (ig, size);
8925                         count.Emit (ec);
8926                         ig.Emit (OpCodes.Mul);
8927                         ig.Emit (OpCodes.Localloc);
8928                 }
8929         }
8930 }