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 (Expr.eclass != ExprClass.Variable){
 420                                         Error (211, "Cannot take the address of non-variables");
 421                                         return null;
 422                                 }
 423
 424                                 if (!ec.InUnsafe) {
 425                                         UnsafeError (loc);
 426                                         return null;
 427                                 }
 428
 429                                 if (!TypeManager.VerifyUnManaged (Expr.Type, loc)){
 430                                         return null;
 431                                 }
 432
 433                                 IVariable variable = Expr as IVariable;
 434                                 bool is_fixed = variable != null && variable.VerifyFixed (false);
 435
 436                                 if (!ec.InFixedInitializer && !is_fixed) {
 437                                         Error (212, "You can only take the address of an unfixed expression inside " +
 438                                                "of a fixed statement initializer");
 439                                         return null;
 440                                 }
 441
 442                                 if (ec.InFixedInitializer && is_fixed) {
 443                                         Error (213, "You can not fix an already fixed expression");
 444                                         return null;
 445                                 }
 446
 447                                 LocalVariableReference lr = Expr as LocalVariableReference;
 448                                 if (lr != null){
 449                                         if (lr.local_info.IsCaptured){
 450                                                 AnonymousMethod.Error_AddressOfCapturedVar (lr.Name, loc);
 451                                                 return null;
 452                                         }
 453                                         lr.local_info.AddressTaken = true;
 454                                         lr.local_info.Used = true;
 455                                 }
 456
 457                                 // According to the specs, a variable is considered definitely assigned if you take
 458                                 // its address.
 459                                 if ((variable != null) && (variable.VariableInfo != null))
 460                                         variable.VariableInfo.SetAssigned (ec);
 461
 462                                 type = TypeManager.GetPointerType (Expr.Type);
 463                                 return this;
 464
 465                         case Operator.Indirection:
 466                                 if (!ec.InUnsafe){
 467                                         UnsafeError (loc);
 468                                         return null;
 469                                 }
 470
 471                                 if (!expr_type.IsPointer){
 472                                         Error (193, "The * or -> operator can only be applied to pointers");
 473                                         return null;
 474                                 }
 475
 476                                 //
 477                                 // We create an Indirection expression, because
 478                                 // it can implement the IMemoryLocation.
 479                                 //
 480                                 return new Indirection (Expr, loc);
 481
 482                         case Operator.UnaryPlus:
 483                                 //
 484                                 // A plus in front of something is just a no-op, so return the child.
 485                                 //
 486                                 return Expr;
 487
 488                         case Operator.UnaryNegation:
 489                                 //
 490                                 // Deals with -literals
 491                                 // int     operator- (int x)
 492                                 // long    operator- (long x)
 493                                 // float   operator- (float f)
 494                                 // double  operator- (double d)
 495                                 // decimal operator- (decimal d)
 496                                 //
 497                                 Expression expr = null;
 498
 499                                 //
 500                                 // transform - - expr into expr
 501                                 //
 502                                 if (Expr is Unary){
 503                                         Unary unary = (Unary) Expr;
 504
 505                                         if (unary.Oper == Operator.UnaryNegation)
 506                                                 return unary.Expr;
 507                                 }
 508
 509                                 //
 510                                 // perform numeric promotions to int,
 511                                 // long, double.
 512                                 //
 513                                 //
 514                                 // The following is inneficient, because we call
 515                                 // ImplicitConversion too many times.
 516                                 //
 517                                 // It is also not clear if we should convert to Float
 518                                 // or Double initially.
 519                                 //
 520                                 if (expr_type == TypeManager.uint32_type){
 521                                         //
 522                                         // FIXME: handle exception to this rule that
 523                                         // permits the int value -2147483648 (-2^31) to
 524                                         // bt wrote as a decimal interger literal
 525                                         //
 526                                         type = TypeManager.int64_type;
 527                                         Expr = Convert.ImplicitConversion (ec, Expr, type, loc);
 528                                         return this;
 529                                 }
 530
 531                                 if (expr_type == TypeManager.uint64_type){
 532                                         //
 533                                         // FIXME: Handle exception of `long value'
 534                                         // -92233720368547758087 (-2^63) to be wrote as
 535                                         // decimal integer literal.
 536                                         //
 537                                         Error23 (expr_type);
 538                                         return null;
 539                                 }
 540
 541                                 if (expr_type == TypeManager.float_type){
 542                                         type = expr_type;
 543                                         return this;
 544                                 }
 545
 546                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.int32_type, loc);
 547                                 if (expr != null){
 548                                         Expr = expr;
 549                                         type = expr.Type;
 550                                         return this;
 551                                 }
 552
 553                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.int64_type, loc);
 554                                 if (expr != null){
 555                                         Expr = expr;
 556                                         type = expr.Type;
 557                                         return this;
 558                                 }
 559
 560                                 expr = Convert.ImplicitConversion (ec, Expr, TypeManager.double_type, loc);
 561                                 if (expr != null){
 562                                         Expr = expr;
 563                                         type = expr.Type;
 564                                         return this;
 565                                 }
 566
 567                                 Error23 (expr_type);
 568                                 return null;
 569                         }
 570
 571                         Error (187, "No such operator '" + OperName (Oper) + "' defined for type '" +
 572                                TypeManager.CSharpName (expr_type) + "'");
 573                         return null;
 574                 }
 575
 576                 public override Expression DoResolve (EmitContext ec)
 577                 {
 578                         if (Oper == Operator.AddressOf)
 579                                 Expr = Expr.ResolveLValue (ec, new EmptyExpression ());
 580                         else
 581                                 Expr = Expr.Resolve (ec);
 582
 583                         if (Expr == null)
 584                                 return null;
 585
 586                         if (TypeManager.IsNullableType (Expr.Type))
 587                                 return new Nullable.LiftedUnaryOperator (Oper, Expr, loc).Resolve (ec);
 588
 589                         eclass = ExprClass.Value;
 590                         return ResolveOperator (ec);
 591                 }
 592
 593                 public override Expression DoResolveLValue (EmitContext ec, Expression right)
 594                 {
 595                         if (Oper == Operator.Indirection)
 596                                 return base.DoResolveLValue (ec, right);
 597
 598                         Error (131, "The left-hand side of an assignment must be a " +
 599                                "variable, property or indexer");
 600                         return null;
 601                 }
 602
 603                 public override void Emit (EmitContext ec)
 604                 {
 605                         ILGenerator ig = ec.ig;
 606
 607                         switch (Oper) {
 608                         case Operator.UnaryPlus:
 609                                 throw new Exception ("This should be caught by Resolve");
 610
 611                         case Operator.UnaryNegation:
 612                                 if (ec.CheckState) {
 613                                         ig.Emit (OpCodes.Ldc_I4_0);
 614                                         if (type == TypeManager.int64_type)
 615                                                 ig.Emit (OpCodes.Conv_U8);
 616                                         Expr.Emit (ec);
 617                                         ig.Emit (OpCodes.Sub_Ovf);
 618                                 } else {
 619                                 Expr.Emit (ec);
 620                                 ig.Emit (OpCodes.Neg);
 621                                 }
 622
 623                                 break;
 624
 625                         case Operator.LogicalNot:
 626                                 Expr.Emit (ec);
 627                                 ig.Emit (OpCodes.Ldc_I4_0);
 628                                 ig.Emit (OpCodes.Ceq);
 629                                 break;
 630
 631                         case Operator.OnesComplement:
 632                                 Expr.Emit (ec);
 633                                 ig.Emit (OpCodes.Not);
 634                                 break;
 635
 636                         case Operator.AddressOf:
 637                                 ((IMemoryLocation)Expr).AddressOf (ec, AddressOp.LoadStore);
 638                                 break;
 639
 640                         default:
 641                                 throw new Exception ("This should not happen: Operator = "
 642                                                      + Oper.ToString ());
 643                         }
 644                 }
 645
 646                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
 647                 {
 648                         if (Oper == Operator.LogicalNot)
 649                                 Expr.EmitBranchable (ec, target, !onTrue);
 650                         else
 651                                 base.EmitBranchable (ec, target, onTrue);
 652                 }
 653
 654                 public override string ToString ()
 655                 {
 656                         return "Unary (" + Oper + ", " + Expr + ")";
 657                 }
 658
 659         }
 660
 661         //
 662         // Unary operators are turned into Indirection expressions
 663         // after semantic analysis (this is so we can take the address
 664         // of an indirection).
 665         //
 666         public class Indirection : Expression, IMemoryLocation, IAssignMethod, IVariable {
 667                 Expression expr;
 668                 LocalTemporary temporary;
 669                 bool prepared;
 670
 671                 public Indirection (Expression expr, Location l)
 672                 {
 673                         this.expr = expr;
 674                         this.type = TypeManager.GetElementType (expr.Type);
 675                         eclass = ExprClass.Variable;
 676                         loc = l;
 677                 }
 678
 679                 void LoadExprValue (EmitContext ec)
 680                 {
 681                 }
 682
 683                 public override void Emit (EmitContext ec)
 684                 {
 685                         if (!prepared)
 686                                 expr.Emit (ec);
 687
 688                         LoadFromPtr (ec.ig, Type);
 689                 }
 690
 691                 public void Emit (EmitContext ec, bool leave_copy)
 692                 {
 693                         Emit (ec);
 694                         if (leave_copy) {
 695                                 ec.ig.Emit (OpCodes.Dup);
 696                                 temporary = new LocalTemporary (ec, expr.Type);
 697                                 temporary.Store (ec);
 698                         }
 699                 }
 700
 701                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
 702                 {
 703                         prepared = prepare_for_load;
 704
 705                         expr.Emit (ec);
 706
 707                         if (prepare_for_load)
 708                                 ec.ig.Emit (OpCodes.Dup);
 709
 710                         source.Emit (ec);
 711                         if (leave_copy) {
 712                                 ec.ig.Emit (OpCodes.Dup);
 713                                 temporary = new LocalTemporary (ec, expr.Type);
 714                                 temporary.Store (ec);
 715                         }
 716
 717                         StoreFromPtr (ec.ig, type);
 718
 719                         if (temporary != null)
 720                                 temporary.Emit (ec);
 721                 }
 722
 723                 public void AddressOf (EmitContext ec, AddressOp Mode)
 724                 {
 725                         expr.Emit (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                 void Error23 (Type t)
 810                 {
 811                         Error (
 812                                 23, "Operator " + OperName (mode) +
 813                                 " cannot be applied to operand of type `" +
 814                                 TypeManager.CSharpName (t) + "'");
 815                 }
 816
 817                 /// <summary>
 818                 ///   Returns whether an object of type `t' can be incremented
 819                 ///   or decremented with add/sub (ie, basically whether we can
 820                 ///   use pre-post incr-decr operations on it, but it is not a
 821                 ///   System.Decimal, which we require operator overloading to catch)
 822                 /// </summary>
 823                 static bool IsIncrementableNumber (Type t)
 824                 {
 825                         return (t == TypeManager.sbyte_type) ||
 826                                 (t == TypeManager.byte_type) ||
 827                                 (t == TypeManager.short_type) ||
 828                                 (t == TypeManager.ushort_type) ||
 829                                 (t == TypeManager.int32_type) ||
 830                                 (t == TypeManager.uint32_type) ||
 831                                 (t == TypeManager.int64_type) ||
 832                                 (t == TypeManager.uint64_type) ||
 833                                 (t == TypeManager.char_type) ||
 834                                 (t.IsSubclassOf (TypeManager.enum_type)) ||
 835                                 (t == TypeManager.float_type) ||
 836                                 (t == TypeManager.double_type) ||
 837                                 (t.IsPointer && t != TypeManager.void_ptr_type);
 838                 }
 839
 840                 Expression ResolveOperator (EmitContext ec)
 841                 {
 842                         Type expr_type = expr.Type;
 843
 844                         //
 845                         // Step 1: Perform Operator Overload location
 846                         //
 847                         Expression mg;
 848                         string op_name;
 849
 850                         if (mode == Mode.PreIncrement || mode == Mode.PostIncrement)
 851                                 op_name = "op_Increment";
 852                         else
 853                                 op_name = "op_Decrement";
 854
 855                         mg = MemberLookup (ec, expr_type, op_name, MemberTypes.Method, AllBindingFlags, loc);
 856
 857                         if (mg == null && expr_type.BaseType != null)
 858                                 mg = MemberLookup (ec, expr_type.BaseType, op_name,
 859                                                    MemberTypes.Method, AllBindingFlags, loc);
 860
 861                         if (mg != null) {
 862                                 method = StaticCallExpr.MakeSimpleCall (
 863                                         ec, (MethodGroupExpr) mg, expr, loc);
 864
 865                                 type = method.Type;
 866                                 return this;
 867                         }
 868
 869                         //
 870                         // The operand of the prefix/postfix increment decrement operators
 871                         // should be an expression that is classified as a variable,
 872                         // a property access or an indexer access
 873                         //
 874                         type = expr_type;
 875                         if (expr.eclass == ExprClass.Variable){
 876                                 LocalVariableReference var = expr as LocalVariableReference;
 877                                 if ((var != null) && var.IsReadOnly)
 878                                         Error (1604, "cannot assign to `" + var.Name + "' because it is readonly");
 879                                 if (IsIncrementableNumber (expr_type) ||
 880                                     expr_type == TypeManager.decimal_type){
 881                                         return this;
 882                                 }
 883                         } else if (expr.eclass == ExprClass.IndexerAccess){
 884                                 IndexerAccess ia = (IndexerAccess) expr;
 885
 886                                 expr = ia.ResolveLValue (ec, this);
 887                                 if (expr == null)
 888                                         return null;
 889
 890                                 return this;
 891                         } else if (expr.eclass == ExprClass.PropertyAccess){
 892                                 PropertyExpr pe = (PropertyExpr) expr;
 893
 894                                 if (pe.VerifyAssignable ())
 895                                         return this;
 896
 897                                 return null;
 898                         } else {
 899                                 expr.Error_UnexpectedKind ("variable, indexer or property access", loc);
 900                                 return null;
 901                         }
 902
 903                         Error (187, "No such operator '" + OperName (mode) + "' defined for type '" +
 904                                TypeManager.CSharpName (expr_type) + "'");
 905                         return null;
 906                 }
 907
 908                 public override Expression DoResolve (EmitContext ec)
 909                 {
 910                         expr = expr.Resolve (ec);
 911
 912                         if (expr == null)
 913                                 return null;
 914
 915                         eclass = ExprClass.Value;
 916
 917                         if (TypeManager.IsNullableType (expr.Type))
 918                                 return new Nullable.LiftedUnaryMutator (mode, expr, loc).Resolve (ec);
 919
 920                         return ResolveOperator (ec);
 921                 }
 922
 923                 static int PtrTypeSize (Type t)
 924                 {
 925                         return GetTypeSize (TypeManager.GetElementType (t));
 926                 }
 927
 928                 //
 929                 // Loads the proper "1" into the stack based on the type, then it emits the
 930                 // opcode for the operation requested
 931                 //
 932                 void LoadOneAndEmitOp (EmitContext ec, Type t)
 933                 {
 934                         //
 935                         // Measure if getting the typecode and using that is more/less efficient
 936                         // that comparing types.  t.GetTypeCode() is an internal call.
 937                         //
 938                         ILGenerator ig = ec.ig;
 939
 940                         if (t == TypeManager.uint64_type || t == TypeManager.int64_type)
 941                                 LongConstant.EmitLong (ig, 1);
 942                         else if (t == TypeManager.double_type)
 943                                 ig.Emit (OpCodes.Ldc_R8, 1.0);
 944                         else if (t == TypeManager.float_type)
 945                                 ig.Emit (OpCodes.Ldc_R4, 1.0F);
 946                         else if (t.IsPointer){
 947                                 int n = PtrTypeSize (t);
 948
 949                                 if (n == 0)
 950                                         ig.Emit (OpCodes.Sizeof, t);
 951                                 else
 952                                         IntConstant.EmitInt (ig, n);
 953                         } else
 954                                 ig.Emit (OpCodes.Ldc_I4_1);
 955
 956                         //
 957                         // Now emit the operation
 958                         //
 959                         if (ec.CheckState){
 960                                 if (t == TypeManager.int32_type ||
 961                                     t == TypeManager.int64_type){
 962                                         if ((mode & Mode.IsDecrement) != 0)
 963                                                 ig.Emit (OpCodes.Sub_Ovf);
 964                                         else
 965                                                 ig.Emit (OpCodes.Add_Ovf);
 966                                 } else if (t == TypeManager.uint32_type ||
 967                                            t == TypeManager.uint64_type){
 968                                         if ((mode & Mode.IsDecrement) != 0)
 969                                                 ig.Emit (OpCodes.Sub_Ovf_Un);
 970                                         else
 971                                                 ig.Emit (OpCodes.Add_Ovf_Un);
 972                                 } else {
 973                                         if ((mode & Mode.IsDecrement) != 0)
 974                                                 ig.Emit (OpCodes.Sub_Ovf);
 975                                         else
 976                                                 ig.Emit (OpCodes.Add_Ovf);
 977                                 }
 978                         } else {
 979                                 if ((mode & Mode.IsDecrement) != 0)
 980                                         ig.Emit (OpCodes.Sub);
 981                                 else
 982                                         ig.Emit (OpCodes.Add);
 983                         }
 984
 985                         if (t == TypeManager.sbyte_type){
 986                                 if (ec.CheckState)
 987                                         ig.Emit (OpCodes.Conv_Ovf_I1);
 988                                 else
 989                                         ig.Emit (OpCodes.Conv_I1);
 990                         } else if (t == TypeManager.byte_type){
 991                                 if (ec.CheckState)
 992                                         ig.Emit (OpCodes.Conv_Ovf_U1);
 993                                 else
 994                                         ig.Emit (OpCodes.Conv_U1);
 995                         } else if (t == TypeManager.short_type){
 996                                 if (ec.CheckState)
 997                                         ig.Emit (OpCodes.Conv_Ovf_I2);
 998                                 else
 999                                         ig.Emit (OpCodes.Conv_I2);
1000                         } else if (t == TypeManager.ushort_type || t == TypeManager.char_type){
1001                                 if (ec.CheckState)
1002                                         ig.Emit (OpCodes.Conv_Ovf_U2);
1003                                 else
1004                                         ig.Emit (OpCodes.Conv_U2);
1005                         }
1006
1007                 }
1008
1009                 void EmitCode (EmitContext ec, bool is_expr)
1010                 {
1011                         recurse = true;
1012                         this.is_expr = is_expr;
1013                         ((IAssignMethod) expr).EmitAssign (ec, this, is_expr && (mode == Mode.PreIncrement || mode == Mode.PreDecrement), true);
1014                 }
1015
1016                 public override void Emit (EmitContext ec)
1017                 {
1018                         //
1019                         // We use recurse to allow ourselfs to be the source
1020                         // of an assignment. This little hack prevents us from
1021                         // having to allocate another expression
1022                         //
1023                         if (recurse) {
1024                                 ((IAssignMethod) expr).Emit (ec, is_expr && (mode == Mode.PostIncrement  || mode == Mode.PostDecrement));
1025                                 if (method == null)
1026                                         LoadOneAndEmitOp (ec, expr.Type);
1027                                 else
1028                                         ec.ig.Emit (OpCodes.Call, method.Method);
1029                                 recurse = false;
1030                                 return;
1031                         }
1032
1033                         EmitCode (ec, true);
1034                 }
1035
1036                 public override void EmitStatement (EmitContext ec)
1037                 {
1038                         EmitCode (ec, false);
1039                 }
1040         }
1041
1042         /// <summary>
1043         ///   Base class for the `Is' and `As' classes.
1044         /// </summary>
1045         ///
1046         /// <remarks>
1047         ///   FIXME: Split this in two, and we get to save the `Operator' Oper
1048         ///   size.
1049         /// </remarks>
1050         public abstract class Probe : Expression {
1051                 public Expression ProbeType;
1052                 protected Expression expr;
1053                 protected Type probe_type;
1054
1055                 public Probe (Expression expr, Expression probe_type, Location l)
1056                 {
1057                         ProbeType = probe_type;
1058                         loc = l;
1059                         this.expr = expr;
1060                 }
1061
1062                 public Expression Expr {
1063                         get {
1064                                 return expr;
1065                         }
1066                 }
1067
1068                 public override Expression DoResolve (EmitContext ec)
1069                 {
1070                         TypeExpr texpr = ProbeType.ResolveAsTypeTerminal (ec);
1071                         if (texpr == null)
1072                                 return null;
1073                         probe_type = texpr.Type;
1074
1075                         CheckObsoleteAttribute (probe_type);
1076
1077                         expr = expr.Resolve (ec);
1078                         if (expr == null)
1079                                 return null;
1080
1081                         if (expr.Type.IsPointer) {
1082                                 Report.Error (244, loc, "\"is\" or \"as\" are not valid on pointer types");
1083                                 return null;
1084                         }
1085                         return this;
1086                 }
1087         }
1088
1089         /// <summary>
1090         ///   Implementation of the `is' operator.
1091         /// </summary>
1092         public class Is : Probe {
1093                 public Is (Expression expr, Expression probe_type, Location l)
1094                         : base (expr, probe_type, l)
1095                 {
1096                 }
1097
1098                 enum Action {
1099                         AlwaysTrue, AlwaysNull, AlwaysFalse, LeaveOnStack, Probe
1100                 }
1101
1102                 Action action;
1103
1104                 public override void Emit (EmitContext ec)
1105                 {
1106                         ILGenerator ig = ec.ig;
1107
1108                         expr.Emit (ec);
1109
1110                         switch (action){
1111                         case Action.AlwaysFalse:
1112                                 ig.Emit (OpCodes.Pop);
1113                                 IntConstant.EmitInt (ig, 0);
1114                                 return;
1115                         case Action.AlwaysTrue:
1116                                 ig.Emit (OpCodes.Pop);
1117                                 IntConstant.EmitInt (ig, 1);
1118                                 return;
1119                         case Action.LeaveOnStack:
1120                                 // the `e != null' rule.
1121                                 ig.Emit (OpCodes.Ldnull);
1122                                 ig.Emit (OpCodes.Ceq);
1123                                 ig.Emit (OpCodes.Ldc_I4_0);
1124                                 ig.Emit (OpCodes.Ceq);
1125                                 return;
1126                         case Action.Probe:
1127                                 ig.Emit (OpCodes.Isinst, probe_type);
1128                                 ig.Emit (OpCodes.Ldnull);
1129                                 ig.Emit (OpCodes.Cgt_Un);
1130                                 return;
1131                         }
1132                         throw new Exception ("never reached");
1133                 }
1134
1135                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
1136                 {
1137                         ILGenerator ig = ec.ig;
1138
1139                         switch (action){
1140                         case Action.AlwaysFalse:
1141                                 if (! onTrue)
1142                                         ig.Emit (OpCodes.Br, target);
1143
1144                                 return;
1145                         case Action.AlwaysTrue:
1146                                 if (onTrue)
1147                                         ig.Emit (OpCodes.Br, target);
1148
1149                                 return;
1150                         case Action.LeaveOnStack:
1151                                 // the `e != null' rule.
1152                                 expr.Emit (ec);
1153                                 ig.Emit (onTrue ? OpCodes.Brtrue : OpCodes.Brfalse, target);
1154                                 return;
1155                         case Action.Probe:
1156                                 expr.Emit (ec);
1157                                 ig.Emit (OpCodes.Isinst, probe_type);
1158                                 ig.Emit (onTrue ? OpCodes.Brtrue : OpCodes.Brfalse, target);
1159                                 return;
1160                         }
1161                         throw new Exception ("never reached");
1162                 }
1163
1164                 public override Expression DoResolve (EmitContext ec)
1165                 {
1166                         Expression e = base.DoResolve (ec);
1167
1168                         if ((e == null) || (expr == null))
1169                                 return null;
1170
1171                         Type etype = expr.Type;
1172                         bool warning_always_matches = false;
1173                         bool warning_never_matches = false;
1174
1175                         type = TypeManager.bool_type;
1176                         eclass = ExprClass.Value;
1177
1178                         //
1179                         // First case, if at compile time, there is an implicit conversion
1180                         // then e != null (objects) or true (value types)
1181                         //
1182                         e = Convert.ImplicitConversionStandard (ec, expr, probe_type, loc);
1183                         if (e != null){
1184                                 expr = e;
1185                                 if (etype.IsValueType)
1186                                         action = Action.AlwaysTrue;
1187                                 else
1188                                         action = Action.LeaveOnStack;
1189
1190                                 warning_always_matches = true;
1191                         } else if (Convert.ExplicitReferenceConversionExists (etype, probe_type)){
1192                                 if (etype.IsGenericParameter)
1193                                         expr = new BoxedCast (expr, etype);
1194
1195                                 //
1196                                 // Second case: explicit reference convresion
1197                                 //
1198                                 if (expr is NullLiteral)
1199                                         action = Action.AlwaysFalse;
1200                                 else
1201                                         action = Action.Probe;
1202                         } else {
1203                                 action = Action.AlwaysFalse;
1204                                 warning_never_matches = true;
1205                         }
1206
1207                         if (warning_always_matches)
1208                                 Warning (183, "The given expression is always of the provided ('{0}') type", TypeManager.CSharpName (probe_type));
1209                         else if (warning_never_matches){
1210                                 if (!(probe_type.IsInterface || expr.Type.IsInterface))
1211                                         Warning (184, "The given expression is never of the provided ('{0}') type", TypeManager.CSharpName (probe_type));
1212                         }
1213
1214                         return this;
1215                 }
1216         }
1217
1218         /// <summary>
1219         ///   Implementation of the `as' operator.
1220         /// </summary>
1221         public class As : Probe {
1222                 public As (Expression expr, Expression probe_type, Location l)
1223                         : base (expr, probe_type, l)
1224                 {
1225                 }
1226
1227                 bool do_isinst = false;
1228
1229                 public override void Emit (EmitContext ec)
1230                 {
1231                         ILGenerator ig = ec.ig;
1232
1233                         expr.Emit (ec);
1234
1235                         if (do_isinst)
1236                                 ig.Emit (OpCodes.Isinst, probe_type);
1237                 }
1238
1239                 static void Error_CannotConvertType (Type source, Type target, Location loc)
1240                 {
1241                         Report.Error (
1242                                 39, loc, "as operator can not convert from `" +
1243                                 TypeManager.CSharpName (source) + "' to `" +
1244                                 TypeManager.CSharpName (target) + "'");
1245                 }
1246
1247                 public override Expression DoResolve (EmitContext ec)
1248                 {
1249                         Expression e = base.DoResolve (ec);
1250
1251                         if (e == null)
1252                                 return null;
1253
1254                         type = probe_type;
1255                         eclass = ExprClass.Value;
1256                         Type etype = expr.Type;
1257
1258                         if (TypeManager.IsValueType (probe_type)){
1259                                 Report.Error (77, loc, "The as operator should be used with a reference type only (" +
1260                                               TypeManager.CSharpName (probe_type) + " is a value type)");
1261                                 return null;
1262
1263                         }
1264
1265                         e = Convert.ImplicitConversion (ec, expr, probe_type, loc);
1266                         if (e != null){
1267                                 expr = e;
1268                                 do_isinst = false;
1269                                 return this;
1270                         }
1271
1272                         if (Convert.ExplicitReferenceConversionExists (etype, probe_type)){
1273                                 if (etype.IsGenericParameter)
1274                                         expr = new BoxedCast (expr, etype);
1275
1276                                 do_isinst = true;
1277                                 return this;
1278                         }
1279
1280                         Error_CannotConvertType (etype, probe_type, loc);
1281                         return null;
1282                 }
1283         }
1284
1285         /// <summary>
1286         ///   This represents a typecast in the source language.
1287         ///
1288         ///   FIXME: Cast expressions have an unusual set of parsing
1289         ///   rules, we need to figure those out.
1290         /// </summary>
1291         public class Cast : Expression {
1292                 Expression target_type;
1293                 Expression expr;
1294
1295                 public Cast (Expression cast_type, Expression expr, Location loc)
1296                 {
1297                         this.target_type = cast_type;
1298                         this.expr = expr;
1299                         this.loc = loc;
1300                 }
1301
1302                 public Expression TargetType {
1303                         get {
1304                                 return target_type;
1305                         }
1306                 }
1307
1308                 public Expression Expr {
1309                         get {
1310                                 return expr;
1311                         }
1312                         set {
1313                                 expr = value;
1314                         }
1315                 }
1316
1317                 bool CheckRange (EmitContext ec, long value, Type type, long min, long max)
1318                 {
1319                         if (!ec.ConstantCheckState)
1320                                 return true;
1321
1322                         if ((value < min) || (value > max)) {
1323                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1324                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1325                                        "syntax to override)");
1326                                 return false;
1327                         }
1328
1329                         return true;
1330                 }
1331
1332                 bool CheckRange (EmitContext ec, ulong value, Type type, ulong max)
1333                 {
1334                         if (!ec.ConstantCheckState)
1335                                 return true;
1336
1337                         if (value > max) {
1338                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1339                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1340                                        "syntax to override)");
1341                                 return false;
1342                         }
1343
1344                         return true;
1345                 }
1346
1347                 bool CheckUnsigned (EmitContext ec, long value, Type type)
1348                 {
1349                         if (!ec.ConstantCheckState)
1350                                 return true;
1351
1352                         if (value < 0) {
1353                                 Error (221, "Constant value `" + value + "' cannot be converted " +
1354                                        "to a `" + TypeManager.CSharpName (type) + "' (use `unchecked' " +
1355                                        "syntax to override)");
1356                                 return false;
1357                         }
1358
1359                         return true;
1360                 }
1361
1362                 /// <summary>
1363                 ///   Attempts to do a compile-time folding of a constant cast.
1364                 /// </summary>
1365                 Expression TryReduce (EmitContext ec, Type target_type)
1366                 {
1367                         Expression real_expr = expr;
1368                         if (real_expr is EnumConstant)
1369                                 real_expr = ((EnumConstant) real_expr).Child;
1370
1371                         if (real_expr is ByteConstant){
1372                                 byte v = ((ByteConstant) real_expr).Value;
1373
1374                                 if (target_type == TypeManager.sbyte_type) {
1375                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1376                                                 return null;
1377                                         return new SByteConstant ((sbyte) v);
1378                                 }
1379                                 if (target_type == TypeManager.short_type)
1380                                         return new ShortConstant ((short) v);
1381                                 if (target_type == TypeManager.ushort_type)
1382                                         return new UShortConstant ((ushort) v);
1383                                 if (target_type == TypeManager.int32_type)
1384                                         return new IntConstant ((int) v);
1385                                 if (target_type == TypeManager.uint32_type)
1386                                         return new UIntConstant ((uint) v);
1387                                 if (target_type == TypeManager.int64_type)
1388                                         return new LongConstant ((long) v);
1389                                 if (target_type == TypeManager.uint64_type)
1390                                         return new ULongConstant ((ulong) v);
1391                                 if (target_type == TypeManager.float_type)
1392                                         return new FloatConstant ((float) v);
1393                                 if (target_type == TypeManager.double_type)
1394                                         return new DoubleConstant ((double) v);
1395                                 if (target_type == TypeManager.char_type)
1396                                         return new CharConstant ((char) v);
1397                                 if (target_type == TypeManager.decimal_type)
1398                                         return new DecimalConstant ((decimal) v);
1399                         }
1400                         if (real_expr is SByteConstant){
1401                                 sbyte v = ((SByteConstant) real_expr).Value;
1402
1403                                 if (target_type == TypeManager.byte_type) {
1404                                         if (!CheckUnsigned (ec, v, target_type))
1405                                                 return null;
1406                                         return new ByteConstant ((byte) v);
1407                                 }
1408                                 if (target_type == TypeManager.short_type)
1409                                         return new ShortConstant ((short) v);
1410                                 if (target_type == TypeManager.ushort_type) {
1411                                         if (!CheckUnsigned (ec, v, target_type))
1412                                                 return null;
1413                                         return new UShortConstant ((ushort) v);
1414                                 } if (target_type == TypeManager.int32_type)
1415                                         return new IntConstant ((int) v);
1416                                 if (target_type == TypeManager.uint32_type) {
1417                                         if (!CheckUnsigned (ec, v, target_type))
1418                                                 return null;
1419                                         return new UIntConstant ((uint) v);
1420                                 } if (target_type == TypeManager.int64_type)
1421                                         return new LongConstant ((long) v);
1422                                 if (target_type == TypeManager.uint64_type) {
1423                                         if (!CheckUnsigned (ec, v, target_type))
1424                                                 return null;
1425                                         return new ULongConstant ((ulong) v);
1426                                 }
1427                                 if (target_type == TypeManager.float_type)
1428                                         return new FloatConstant ((float) v);
1429                                 if (target_type == TypeManager.double_type)
1430                                         return new DoubleConstant ((double) v);
1431                                 if (target_type == TypeManager.char_type) {
1432                                         if (!CheckUnsigned (ec, v, target_type))
1433                                                 return null;
1434                                         return new CharConstant ((char) v);
1435                                 }
1436                                 if (target_type == TypeManager.decimal_type)
1437                                         return new DecimalConstant ((decimal) v);
1438                         }
1439                         if (real_expr is ShortConstant){
1440                                 short v = ((ShortConstant) real_expr).Value;
1441
1442                                 if (target_type == TypeManager.byte_type) {
1443                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1444                                                 return null;
1445                                         return new ByteConstant ((byte) v);
1446                                 }
1447                                 if (target_type == TypeManager.sbyte_type) {
1448                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1449                                                 return null;
1450                                         return new SByteConstant ((sbyte) v);
1451                                 }
1452                                 if (target_type == TypeManager.ushort_type) {
1453                                         if (!CheckUnsigned (ec, v, target_type))
1454                                                 return null;
1455                                         return new UShortConstant ((ushort) v);
1456                                 }
1457                                 if (target_type == TypeManager.int32_type)
1458                                         return new IntConstant ((int) v);
1459                                 if (target_type == TypeManager.uint32_type) {
1460                                         if (!CheckUnsigned (ec, v, target_type))
1461                                                 return null;
1462                                         return new UIntConstant ((uint) v);
1463                                 }
1464                                 if (target_type == TypeManager.int64_type)
1465                                         return new LongConstant ((long) v);
1466                                 if (target_type == TypeManager.uint64_type) {
1467                                         if (!CheckUnsigned (ec, v, target_type))
1468                                                 return null;
1469                                         return new ULongConstant ((ulong) v);
1470                                 }
1471                                 if (target_type == TypeManager.float_type)
1472                                         return new FloatConstant ((float) v);
1473                                 if (target_type == TypeManager.double_type)
1474                                         return new DoubleConstant ((double) v);
1475                                 if (target_type == TypeManager.char_type) {
1476                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1477                                                 return null;
1478                                         return new CharConstant ((char) v);
1479                                 }
1480                                 if (target_type == TypeManager.decimal_type)
1481                                         return new DecimalConstant ((decimal) v);
1482                         }
1483                         if (real_expr is UShortConstant){
1484                                 ushort v = ((UShortConstant) real_expr).Value;
1485
1486                                 if (target_type == TypeManager.byte_type) {
1487                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1488                                                 return null;
1489                                         return new ByteConstant ((byte) v);
1490                                 }
1491                                 if (target_type == TypeManager.sbyte_type) {
1492                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1493                                                 return null;
1494                                         return new SByteConstant ((sbyte) v);
1495                                 }
1496                                 if (target_type == TypeManager.short_type) {
1497                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1498                                                 return null;
1499                                         return new ShortConstant ((short) v);
1500                                 }
1501                                 if (target_type == TypeManager.int32_type)
1502                                         return new IntConstant ((int) v);
1503                                 if (target_type == TypeManager.uint32_type)
1504                                         return new UIntConstant ((uint) v);
1505                                 if (target_type == TypeManager.int64_type)
1506                                         return new LongConstant ((long) v);
1507                                 if (target_type == TypeManager.uint64_type)
1508                                         return new ULongConstant ((ulong) v);
1509                                 if (target_type == TypeManager.float_type)
1510                                         return new FloatConstant ((float) v);
1511                                 if (target_type == TypeManager.double_type)
1512                                         return new DoubleConstant ((double) v);
1513                                 if (target_type == TypeManager.char_type) {
1514                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1515                                                 return null;
1516                                         return new CharConstant ((char) v);
1517                                 }
1518                                 if (target_type == TypeManager.decimal_type)
1519                                         return new DecimalConstant ((decimal) v);
1520                         }
1521                         if (real_expr is IntConstant){
1522                                 int v = ((IntConstant) real_expr).Value;
1523
1524                                 if (target_type == TypeManager.byte_type) {
1525                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1526                                                 return null;
1527                                         return new ByteConstant ((byte) v);
1528                                 }
1529                                 if (target_type == TypeManager.sbyte_type) {
1530                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1531                                                 return null;
1532                                         return new SByteConstant ((sbyte) v);
1533                                 }
1534                                 if (target_type == TypeManager.short_type) {
1535                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1536                                                 return null;
1537                                         return new ShortConstant ((short) v);
1538                                 }
1539                                 if (target_type == TypeManager.ushort_type) {
1540                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1541                                                 return null;
1542                                         return new UShortConstant ((ushort) v);
1543                                 }
1544                                 if (target_type == TypeManager.uint32_type) {
1545                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1546                                                 return null;
1547                                         return new UIntConstant ((uint) v);
1548                                 }
1549                                 if (target_type == TypeManager.int64_type)
1550                                         return new LongConstant ((long) v);
1551                                 if (target_type == TypeManager.uint64_type) {
1552                                         if (!CheckUnsigned (ec, v, target_type))
1553                                                 return null;
1554                                         return new ULongConstant ((ulong) v);
1555                                 }
1556                                 if (target_type == TypeManager.float_type)
1557                                         return new FloatConstant ((float) v);
1558                                 if (target_type == TypeManager.double_type)
1559                                         return new DoubleConstant ((double) v);
1560                                 if (target_type == TypeManager.char_type) {
1561                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1562                                                 return null;
1563                                         return new CharConstant ((char) v);
1564                                 }
1565                                 if (target_type == TypeManager.decimal_type)
1566                                         return new DecimalConstant ((decimal) v);
1567                         }
1568                         if (real_expr is UIntConstant){
1569                                 uint v = ((UIntConstant) real_expr).Value;
1570
1571                                 if (target_type == TypeManager.byte_type) {
1572                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1573                                                 return null;
1574                                         return new ByteConstant ((byte) v);
1575                                 }
1576                                 if (target_type == TypeManager.sbyte_type) {
1577                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1578                                                 return null;
1579                                         return new SByteConstant ((sbyte) v);
1580                                 }
1581                                 if (target_type == TypeManager.short_type) {
1582                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1583                                                 return null;
1584                                         return new ShortConstant ((short) v);
1585                                 }
1586                                 if (target_type == TypeManager.ushort_type) {
1587                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1588                                                 return null;
1589                                         return new UShortConstant ((ushort) v);
1590                                 }
1591                                 if (target_type == TypeManager.int32_type) {
1592                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1593                                                 return null;
1594                                         return new IntConstant ((int) v);
1595                                 }
1596                                 if (target_type == TypeManager.int64_type)
1597                                         return new LongConstant ((long) v);
1598                                 if (target_type == TypeManager.uint64_type)
1599                                         return new ULongConstant ((ulong) v);
1600                                 if (target_type == TypeManager.float_type)
1601                                         return new FloatConstant ((float) v);
1602                                 if (target_type == TypeManager.double_type)
1603                                         return new DoubleConstant ((double) v);
1604                                 if (target_type == TypeManager.char_type) {
1605                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1606                                                 return null;
1607                                         return new CharConstant ((char) v);
1608                                 }
1609                                 if (target_type == TypeManager.decimal_type)
1610                                         return new DecimalConstant ((decimal) v);
1611                         }
1612                         if (real_expr is LongConstant){
1613                                 long v = ((LongConstant) real_expr).Value;
1614
1615                                 if (target_type == TypeManager.byte_type) {
1616                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1617                                                 return null;
1618                                         return new ByteConstant ((byte) v);
1619                                 }
1620                                 if (target_type == TypeManager.sbyte_type) {
1621                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1622                                                 return null;
1623                                         return new SByteConstant ((sbyte) v);
1624                                 }
1625                                 if (target_type == TypeManager.short_type) {
1626                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1627                                                 return null;
1628                                         return new ShortConstant ((short) v);
1629                                 }
1630                                 if (target_type == TypeManager.ushort_type) {
1631                                         if (!CheckRange (ec, v, target_type, UInt16.MinValue, UInt16.MaxValue))
1632                                                 return null;
1633                                         return new UShortConstant ((ushort) v);
1634                                 }
1635                                 if (target_type == TypeManager.int32_type) {
1636                                         if (!CheckRange (ec, v, target_type, Int32.MinValue, Int32.MaxValue))
1637                                                 return null;
1638                                         return new IntConstant ((int) v);
1639                                 }
1640                                 if (target_type == TypeManager.uint32_type) {
1641                                         if (!CheckRange (ec, v, target_type, UInt32.MinValue, UInt32.MaxValue))
1642                                                 return null;
1643                                         return new UIntConstant ((uint) v);
1644                                 }
1645                                 if (target_type == TypeManager.uint64_type) {
1646                                         if (!CheckUnsigned (ec, v, target_type))
1647                                                 return null;
1648                                         return new ULongConstant ((ulong) v);
1649                                 }
1650                                 if (target_type == TypeManager.float_type)
1651                                         return new FloatConstant ((float) v);
1652                                 if (target_type == TypeManager.double_type)
1653                                         return new DoubleConstant ((double) v);
1654                                 if (target_type == TypeManager.char_type) {
1655                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1656                                                 return null;
1657                                         return new CharConstant ((char) v);
1658                                 }
1659                                 if (target_type == TypeManager.decimal_type)
1660                                         return new DecimalConstant ((decimal) v);
1661                         }
1662                         if (real_expr is ULongConstant){
1663                                 ulong v = ((ULongConstant) real_expr).Value;
1664
1665                                 if (target_type == TypeManager.byte_type) {
1666                                         if (!CheckRange (ec, v, target_type, Byte.MaxValue))
1667                                                 return null;
1668                                         return new ByteConstant ((byte) v);
1669                                 }
1670                                 if (target_type == TypeManager.sbyte_type) {
1671                                         if (!CheckRange (ec, v, target_type, (ulong) SByte.MaxValue))
1672                                                 return null;
1673                                         return new SByteConstant ((sbyte) v);
1674                                 }
1675                                 if (target_type == TypeManager.short_type) {
1676                                         if (!CheckRange (ec, v, target_type, (ulong) Int16.MaxValue))
1677                                                 return null;
1678                                         return new ShortConstant ((short) v);
1679                                 }
1680                                 if (target_type == TypeManager.ushort_type) {
1681                                         if (!CheckRange (ec, v, target_type, UInt16.MaxValue))
1682                                                 return null;
1683                                         return new UShortConstant ((ushort) v);
1684                                 }
1685                                 if (target_type == TypeManager.int32_type) {
1686                                         if (!CheckRange (ec, v, target_type, Int32.MaxValue))
1687                                                 return null;
1688                                         return new IntConstant ((int) v);
1689                                 }
1690                                 if (target_type == TypeManager.uint32_type) {
1691                                         if (!CheckRange (ec, v, target_type, UInt32.MaxValue))
1692                                                 return null;
1693                                         return new UIntConstant ((uint) v);
1694                                 }
1695                                 if (target_type == TypeManager.int64_type) {
1696                                         if (!CheckRange (ec, v, target_type, (ulong) Int64.MaxValue))
1697                                                 return null;
1698                                         return new LongConstant ((long) v);
1699                                 }
1700                                 if (target_type == TypeManager.float_type)
1701                                         return new FloatConstant ((float) v);
1702                                 if (target_type == TypeManager.double_type)
1703                                         return new DoubleConstant ((double) v);
1704                                 if (target_type == TypeManager.char_type) {
1705                                         if (!CheckRange (ec, v, target_type, Char.MaxValue))
1706                                                 return null;
1707                                         return new CharConstant ((char) v);
1708                                 }
1709                                 if (target_type == TypeManager.decimal_type)
1710                                         return new DecimalConstant ((decimal) v);
1711                         }
1712                         if (real_expr is FloatConstant){
1713                                 float v = ((FloatConstant) real_expr).Value;
1714
1715                                 if (target_type == TypeManager.byte_type)
1716                                         return new ByteConstant ((byte) v);
1717                                 if (target_type == TypeManager.sbyte_type)
1718                                         return new SByteConstant ((sbyte) v);
1719                                 if (target_type == TypeManager.short_type)
1720                                         return new ShortConstant ((short) v);
1721                                 if (target_type == TypeManager.ushort_type)
1722                                         return new UShortConstant ((ushort) v);
1723                                 if (target_type == TypeManager.int32_type)
1724                                         return new IntConstant ((int) v);
1725                                 if (target_type == TypeManager.uint32_type)
1726                                         return new UIntConstant ((uint) v);
1727                                 if (target_type == TypeManager.int64_type)
1728                                         return new LongConstant ((long) v);
1729                                 if (target_type == TypeManager.uint64_type)
1730                                         return new ULongConstant ((ulong) v);
1731                                 if (target_type == TypeManager.double_type)
1732                                         return new DoubleConstant ((double) v);
1733                                 if (target_type == TypeManager.char_type)
1734                                         return new CharConstant ((char) v);
1735                                 if (target_type == TypeManager.decimal_type)
1736                                         return new DecimalConstant ((decimal) v);
1737                         }
1738                         if (real_expr is DoubleConstant){
1739                                 double v = ((DoubleConstant) real_expr).Value;
1740
1741                                 if (target_type == TypeManager.byte_type){
1742                                         return new ByteConstant ((byte) v);
1743                                 } if (target_type == TypeManager.sbyte_type)
1744                                         return new SByteConstant ((sbyte) v);
1745                                 if (target_type == TypeManager.short_type)
1746                                         return new ShortConstant ((short) v);
1747                                 if (target_type == TypeManager.ushort_type)
1748                                         return new UShortConstant ((ushort) v);
1749                                 if (target_type == TypeManager.int32_type)
1750                                         return new IntConstant ((int) v);
1751                                 if (target_type == TypeManager.uint32_type)
1752                                         return new UIntConstant ((uint) v);
1753                                 if (target_type == TypeManager.int64_type)
1754                                         return new LongConstant ((long) v);
1755                                 if (target_type == TypeManager.uint64_type)
1756                                         return new ULongConstant ((ulong) v);
1757                                 if (target_type == TypeManager.float_type)
1758                                         return new FloatConstant ((float) v);
1759                                 if (target_type == TypeManager.char_type)
1760                                         return new CharConstant ((char) v);
1761                                 if (target_type == TypeManager.decimal_type)
1762                                         return new DecimalConstant ((decimal) v);
1763                         }
1764
1765                         if (real_expr is CharConstant){
1766                                 char v = ((CharConstant) real_expr).Value;
1767
1768                                 if (target_type == TypeManager.byte_type) {
1769                                         if (!CheckRange (ec, v, target_type, Byte.MinValue, Byte.MaxValue))
1770                                                 return null;
1771                                         return new ByteConstant ((byte) v);
1772                                 }
1773                                 if (target_type == TypeManager.sbyte_type) {
1774                                         if (!CheckRange (ec, v, target_type, SByte.MinValue, SByte.MaxValue))
1775                                                 return null;
1776                                         return new SByteConstant ((sbyte) v);
1777                                 }
1778                                 if (target_type == TypeManager.short_type) {
1779                                         if (!CheckRange (ec, v, target_type, Int16.MinValue, Int16.MaxValue))
1780                                                 return null;
1781                                         return new ShortConstant ((short) v);
1782                                 }
1783                                 if (target_type == TypeManager.int32_type)
1784                                         return new IntConstant ((int) v);
1785                                 if (target_type == TypeManager.uint32_type)
1786                                         return new UIntConstant ((uint) v);
1787                                 if (target_type == TypeManager.int64_type)
1788                                         return new LongConstant ((long) v);
1789                                 if (target_type == TypeManager.uint64_type)
1790                                         return new ULongConstant ((ulong) v);
1791                                 if (target_type == TypeManager.float_type)
1792                                         return new FloatConstant ((float) v);
1793                                 if (target_type == TypeManager.double_type)
1794                                         return new DoubleConstant ((double) v);
1795                                 if (target_type == TypeManager.char_type) {
1796                                         if (!CheckRange (ec, v, target_type, Char.MinValue, Char.MaxValue))
1797                                                 return null;
1798                                         return new CharConstant ((char) v);
1799                                 }
1800                                 if (target_type == TypeManager.decimal_type)
1801                                         return new DecimalConstant ((decimal) v);
1802                         }
1803
1804                         return null;
1805                 }
1806
1807                 public override Expression DoResolve (EmitContext ec)
1808                 {
1809                         expr = expr.Resolve (ec);
1810                         if (expr == null)
1811                                 return null;
1812
1813                         TypeExpr target = target_type.ResolveAsTypeTerminal (ec);
1814                         if (target == null)
1815                                 return null;
1816
1817                         type = target.Type;
1818
1819                         CheckObsoleteAttribute (type);
1820
1821                         if (type.IsAbstract && type.IsSealed) {
1822                                 Report.Error (716, loc, "Cannot convert to static type '{0}'", TypeManager.CSharpName (type));
1823                                 return null;
1824                         }
1825
1826                         eclass = ExprClass.Value;
1827
1828                         if (expr is Constant){
1829                                 Expression e = TryReduce (ec, type);
1830
1831                                 if (e != null)
1832                                         return e;
1833                         }
1834
1835                         if (type.IsPointer && !ec.InUnsafe) {
1836                                 UnsafeError (loc);
1837                                 return null;
1838                         }
1839                         expr = Convert.ExplicitConversion (ec, expr, type, loc);
1840                         return expr;
1841                 }
1842
1843                 public override void Emit (EmitContext ec)
1844                 {
1845                         //
1846                         // This one will never happen
1847                         //
1848                         throw new Exception ("Should not happen");
1849                 }
1850         }
1851
1852         /// <summary>
1853         ///   Binary operators
1854         /// </summary>
1855         public class Binary : Expression {
1856                 public enum Operator : byte {
1857                         Multiply, Division, Modulus,
1858                         Addition, Subtraction,
1859                         LeftShift, RightShift,
1860                         LessThan, GreaterThan, LessThanOrEqual, GreaterThanOrEqual,
1861                         Equality, Inequality,
1862                         BitwiseAnd,
1863                         ExclusiveOr,
1864                         BitwiseOr,
1865                         LogicalAnd,
1866                         LogicalOr,
1867                         TOP
1868                 }
1869
1870                 Operator oper;
1871                 Expression left, right;
1872
1873                 // This must be kept in sync with Operator!!!
1874                 public static readonly string [] oper_names;
1875
1876                 static Binary ()
1877                 {
1878                         oper_names = new string [(int) Operator.TOP];
1879
1880                         oper_names [(int) Operator.Multiply] = "op_Multiply";
1881                         oper_names [(int) Operator.Division] = "op_Division";
1882                         oper_names [(int) Operator.Modulus] = "op_Modulus";
1883                         oper_names [(int) Operator.Addition] = "op_Addition";
1884                         oper_names [(int) Operator.Subtraction] = "op_Subtraction";
1885                         oper_names [(int) Operator.LeftShift] = "op_LeftShift";
1886                         oper_names [(int) Operator.RightShift] = "op_RightShift";
1887                         oper_names [(int) Operator.LessThan] = "op_LessThan";
1888                         oper_names [(int) Operator.GreaterThan] = "op_GreaterThan";
1889                         oper_names [(int) Operator.LessThanOrEqual] = "op_LessThanOrEqual";
1890                         oper_names [(int) Operator.GreaterThanOrEqual] = "op_GreaterThanOrEqual";
1891                         oper_names [(int) Operator.Equality] = "op_Equality";
1892                         oper_names [(int) Operator.Inequality] = "op_Inequality";
1893                         oper_names [(int) Operator.BitwiseAnd] = "op_BitwiseAnd";
1894                         oper_names [(int) Operator.BitwiseOr] = "op_BitwiseOr";
1895                         oper_names [(int) Operator.ExclusiveOr] = "op_ExclusiveOr";
1896                         oper_names [(int) Operator.LogicalOr] = "op_LogicalOr";
1897                         oper_names [(int) Operator.LogicalAnd] = "op_LogicalAnd";
1898                 }
1899
1900                 public Binary (Operator oper, Expression left, Expression right, Location loc)
1901                 {
1902                         this.oper = oper;
1903                         this.left = left;
1904                         this.right = right;
1905                         this.loc = loc;
1906                 }
1907
1908                 public Operator Oper {
1909                         get {
1910                                 return oper;
1911                         }
1912                         set {
1913                                 oper = value;
1914                         }
1915                 }
1916
1917                 public Expression Left {
1918                         get {
1919                                 return left;
1920                         }
1921                         set {
1922                                 left = value;
1923                         }
1924                 }
1925
1926                 public Expression Right {
1927                         get {
1928                                 return right;
1929                         }
1930                         set {
1931                                 right = value;
1932                         }
1933                 }
1934
1935
1936                 /// <summary>
1937                 ///   Returns a stringified representation of the Operator
1938                 /// </summary>
1939                 static string OperName (Operator oper)
1940                 {
1941                         switch (oper){
1942                         case Operator.Multiply:
1943                                 return "*";
1944                         case Operator.Division:
1945                                 return "/";
1946                         case Operator.Modulus:
1947                                 return "%";
1948                         case Operator.Addition:
1949                                 return "+";
1950                         case Operator.Subtraction:
1951                                 return "-";
1952                         case Operator.LeftShift:
1953                                 return "<<";
1954                         case Operator.RightShift:
1955                                 return ">>";
1956                         case Operator.LessThan:
1957                                 return "<";
1958                         case Operator.GreaterThan:
1959                                 return ">";
1960                         case Operator.LessThanOrEqual:
1961                                 return "<=";
1962                         case Operator.GreaterThanOrEqual:
1963                                 return ">=";
1964                         case Operator.Equality:
1965                                 return "==";
1966                         case Operator.Inequality:
1967                                 return "!=";
1968                         case Operator.BitwiseAnd:
1969                                 return "&";
1970                         case Operator.BitwiseOr:
1971                                 return "|";
1972                         case Operator.ExclusiveOr:
1973                                 return "^";
1974                         case Operator.LogicalOr:
1975                                 return "||";
1976                         case Operator.LogicalAnd:
1977                                 return "&&";
1978                         }
1979
1980                         return oper.ToString ();
1981                 }
1982
1983                 public override string ToString ()
1984                 {
1985                         return "operator " + OperName (oper) + "(" + left.ToString () + ", " +
1986                                 right.ToString () + ")";
1987                 }
1988
1989                 Expression ForceConversion (EmitContext ec, Expression expr, Type target_type)
1990                 {
1991                         if (expr.Type == target_type)
1992                                 return expr;
1993
1994                         return Convert.ImplicitConversion (ec, expr, target_type, loc);
1995                 }
1996
1997                 public static void Error_OperatorAmbiguous (Location loc, Operator oper, Type l, Type r)
1998                 {
1999                         Report.Error (
2000                                 34, loc, "Operator `" + OperName (oper)
2001                                 + "' is ambiguous on operands of type `"
2002                                 + TypeManager.CSharpName (l) + "' "
2003                                 + "and `" + TypeManager.CSharpName (r)
2004                                 + "'");
2005                 }
2006
2007                 bool IsOfType (EmitContext ec, Type l, Type r, Type t, bool check_user_conversions)
2008                 {
2009                         if ((l == t) || (r == t))
2010                                 return true;
2011
2012                         if (!check_user_conversions)
2013                                 return false;
2014
2015                         if (Convert.ImplicitUserConversionExists (ec, l, t))
2016                                 return true;
2017                         else if (Convert.ImplicitUserConversionExists (ec, r, t))
2018                                 return true;
2019                         else
2020                                 return false;
2021                 }
2022
2023                 //
2024                 // Note that handling the case l == Decimal || r == Decimal
2025                 // is taken care of by the Step 1 Operator Overload resolution.
2026                 //
2027                 // If `check_user_conv' is true, we also check whether a user-defined conversion
2028                 // exists.  Note that we only need to do this if both arguments are of a user-defined
2029                 // type, otherwise ConvertImplict() already finds the user-defined conversion for us,
2030                 // so we don't explicitly check for performance reasons.
2031                 //
2032                 bool DoNumericPromotions (EmitContext ec, Type l, Type r, bool check_user_conv)
2033                 {
2034                         if (IsOfType (ec, l, r, TypeManager.double_type, check_user_conv)){
2035                                 //
2036                                 // If either operand is of type double, the other operand is
2037                                 // conveted to type double.
2038                                 //
2039                                 if (r != TypeManager.double_type)
2040                                         right = Convert.ImplicitConversion (ec, right, TypeManager.double_type, loc);
2041                                 if (l != TypeManager.double_type)
2042                                         left = Convert.ImplicitConversion (ec, left, TypeManager.double_type, loc);
2043
2044                                 type = TypeManager.double_type;
2045                         } else if (IsOfType (ec, l, r, TypeManager.float_type, check_user_conv)){
2046                                 //
2047                                 // if either operand is of type float, the other operand is
2048                                 // converted to type float.
2049                                 //
2050                                 if (r != TypeManager.double_type)
2051                                         right = Convert.ImplicitConversion (ec, right, TypeManager.float_type, loc);
2052                                 if (l != TypeManager.double_type)
2053                                         left = Convert.ImplicitConversion (ec, left, TypeManager.float_type, loc);
2054                                 type = TypeManager.float_type;
2055                         } else if (IsOfType (ec, l, r, TypeManager.uint64_type, check_user_conv)){
2056                                 Expression e;
2057                                 Type other;
2058                                 //
2059                                 // If either operand is of type ulong, the other operand is
2060                                 // converted to type ulong.  or an error ocurrs if the other
2061                                 // operand is of type sbyte, short, int or long
2062                                 //
2063                                 if (l == TypeManager.uint64_type){
2064                                         if (r != TypeManager.uint64_type){
2065                                                 if (right is IntConstant){
2066                                                         IntConstant ic = (IntConstant) right;
2067
2068                                                         e = Convert.TryImplicitIntConversion (l, ic);
2069                                                         if (e != null)
2070                                                                 right = e;
2071                                                 } else if (right is LongConstant){
2072                                                         long ll = ((LongConstant) right).Value;
2073
2074                                                         if (ll >= 0)
2075                                                                 right = new ULongConstant ((ulong) ll);
2076                                                 } else {
2077                                                         e = Convert.ImplicitNumericConversion (ec, right, l, loc);
2078                                                         if (e != null)
2079                                                                 right = e;
2080                                                 }
2081                                         }
2082                                         other = right.Type;
2083                                 } else {
2084                                         if (left is IntConstant){
2085                                                 e = Convert.TryImplicitIntConversion (r, (IntConstant) left);
2086                                                 if (e != null)
2087                                                         left = e;
2088                                         } else if (left is LongConstant){
2089                                                 long ll = ((LongConstant) left).Value;
2090
2091                                                 if (ll > 0)
2092                                                         left = new ULongConstant ((ulong) ll);
2093                                         } else {
2094                                                 e = Convert.ImplicitNumericConversion (ec, left, r, loc);
2095                                                 if (e != null)
2096                                                         left = e;
2097                                         }
2098                                         other = left.Type;
2099                                 }
2100
2101                                 if ((other == TypeManager.sbyte_type) ||
2102                                     (other == TypeManager.short_type) ||
2103                                     (other == TypeManager.int32_type) ||
2104                                     (other == TypeManager.int64_type))
2105                                         Error_OperatorAmbiguous (loc, oper, l, r);
2106                                 else {
2107                                         left = ForceConversion (ec, left, TypeManager.uint64_type);
2108                                         right = ForceConversion (ec, right, TypeManager.uint64_type);
2109                                 }
2110                                 type = TypeManager.uint64_type;
2111                         } else if (IsOfType (ec, l, r, TypeManager.int64_type, check_user_conv)){
2112                                 //
2113                                 // If either operand is of type long, the other operand is converted
2114                                 // to type long.
2115                                 //
2116                                 if (l != TypeManager.int64_type)
2117                                         left = Convert.ImplicitConversion (ec, left, TypeManager.int64_type, loc);
2118                                 if (r != TypeManager.int64_type)
2119                                         right = Convert.ImplicitConversion (ec, right, TypeManager.int64_type, loc);
2120
2121                                 type = TypeManager.int64_type;
2122                         } else if (IsOfType (ec, l, r, TypeManager.uint32_type, check_user_conv)){
2123                                 //
2124                                 // If either operand is of type uint, and the other
2125                                 // operand is of type sbyte, short or int, othe operands are
2126                                 // converted to type long (unless we have an int constant).
2127                                 //
2128                                 Type other = null;
2129
2130                                 if (l == TypeManager.uint32_type){
2131                                         if (right is IntConstant){
2132                                                 IntConstant ic = (IntConstant) right;
2133                                                 int val = ic.Value;
2134
2135                                                 if (val >= 0){
2136                                                         right = new UIntConstant ((uint) val);
2137                                                         type = l;
2138
2139                                                         return true;
2140                                                 }
2141                                         }
2142                                         other = r;
2143                                 } else if (r == TypeManager.uint32_type){
2144                                         if (left is IntConstant){
2145                                                 IntConstant ic = (IntConstant) left;
2146                                                 int val = ic.Value;
2147
2148                                                 if (val >= 0){
2149                                                         left = new UIntConstant ((uint) val);
2150                                                         type = r;
2151                                                         return true;
2152                                                 }
2153                                         }
2154
2155                                         other = l;
2156                                 }
2157
2158                                 if ((other == TypeManager.sbyte_type) ||
2159                                     (other == TypeManager.short_type) ||
2160                                     (other == TypeManager.int32_type)){
2161                                         left = ForceConversion (ec, left, TypeManager.int64_type);
2162                                         right = ForceConversion (ec, right, TypeManager.int64_type);
2163                                         type = TypeManager.int64_type;
2164                                 } else {
2165                                         //
2166                                         // if either operand is of type uint, the other
2167                                         // operand is converd to type uint
2168                                         //
2169                                         left = ForceConversion (ec, left, TypeManager.uint32_type);
2170                                         right = ForceConversion (ec, right, TypeManager.uint32_type);
2171                                         type = TypeManager.uint32_type;
2172                                 }
2173                         } else if (l == TypeManager.decimal_type || r == TypeManager.decimal_type){
2174                                 if (l != TypeManager.decimal_type)
2175                                         left = Convert.ImplicitConversion (ec, left, TypeManager.decimal_type, loc);
2176
2177                                 if (r != TypeManager.decimal_type)
2178                                         right = Convert.ImplicitConversion (ec, right, TypeManager.decimal_type, loc);
2179                                 type = TypeManager.decimal_type;
2180                         } else {
2181                                 left = ForceConversion (ec, left, TypeManager.int32_type);
2182                                 right = ForceConversion (ec, right, TypeManager.int32_type);
2183
2184                                 type = TypeManager.int32_type;
2185                         }
2186
2187                         return (left != null) && (right != null);
2188                 }
2189
2190                 static public void Error_OperatorCannotBeApplied (Location loc, string name, Type l, Type r)
2191                 {
2192                         Report.Error (19, loc,
2193                                "Operator " + name + " cannot be applied to operands of type `" +
2194                                TypeManager.CSharpName (l) + "' and `" +
2195                                TypeManager.CSharpName (r) + "'");
2196                 }
2197
2198                 void Error_OperatorCannotBeApplied ()
2199                 {
2200                         Error_OperatorCannotBeApplied (loc, OperName (oper), left.Type, right.Type);
2201                 }
2202
2203                 static bool is_unsigned (Type t)
2204                 {
2205                         return (t == TypeManager.uint32_type || t == TypeManager.uint64_type ||
2206                                 t == TypeManager.short_type || t == TypeManager.byte_type);
2207                 }
2208
2209                 static bool is_user_defined (Type t)
2210                 {
2211                         if (t.IsSubclassOf (TypeManager.value_type) &&
2212                             (!TypeManager.IsBuiltinType (t) || t == TypeManager.decimal_type))
2213                                 return true;
2214                         else
2215                                 return false;
2216                 }
2217
2218                 Expression Make32or64 (EmitContext ec, Expression e)
2219                 {
2220                         Type t= e.Type;
2221
2222                         if (t == TypeManager.int32_type || t == TypeManager.uint32_type ||
2223                             t == TypeManager.int64_type || t == TypeManager.uint64_type)
2224                                 return e;
2225                         Expression ee = Convert.ImplicitConversion (ec, e, TypeManager.int32_type, loc);
2226                         if (ee != null)
2227                                 return ee;
2228                         ee = Convert.ImplicitConversion (ec, e, TypeManager.uint32_type, loc);
2229                         if (ee != null)
2230                                 return ee;
2231                         ee = Convert.ImplicitConversion (ec, e, TypeManager.int64_type, loc);
2232                         if (ee != null)
2233                                 return ee;
2234                         ee = Convert.ImplicitConversion (ec, e, TypeManager.uint64_type, loc);
2235                         if (ee != null)
2236                                 return ee;
2237                         return null;
2238                 }
2239
2240                 Expression CheckShiftArguments (EmitContext ec)
2241                 {
2242                         Expression e;
2243
2244                         e = ForceConversion (ec, right, TypeManager.int32_type);
2245                         if (e == null){
2246                                 Error_OperatorCannotBeApplied ();
2247                                 return null;
2248                         }
2249                         right = e;
2250
2251                         if (((e = Convert.ImplicitConversion (ec, left, TypeManager.int32_type, loc)) != null) ||
2252                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.uint32_type, loc)) != null) ||
2253                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.int64_type, loc)) != null) ||
2254                             ((e = Convert.ImplicitConversion (ec, left, TypeManager.uint64_type, loc)) != null)){
2255                                 left = e;
2256                                 type = e.Type;
2257
2258                                 if (type == TypeManager.int32_type || type == TypeManager.uint32_type){
2259                                         right = new Binary (Binary.Operator.BitwiseAnd, right, new IntLiteral (31), loc);
2260                                         right = right.DoResolve (ec);
2261                                 } else {
2262                                         right = new Binary (Binary.Operator.BitwiseAnd, right, new IntLiteral (63), loc);
2263                                         right = right.DoResolve (ec);
2264                                 }
2265
2266                                 return this;
2267                         }
2268                         Error_OperatorCannotBeApplied ();
2269                         return null;
2270                 }
2271
2272                 Expression ResolveOperator (EmitContext ec)
2273                 {
2274                         Type l = left.Type;
2275                         Type r = right.Type;
2276
2277                         //
2278                         // Special cases: string or type parameter comapred to null
2279                         //
2280                         if (oper == Operator.Equality || oper == Operator.Inequality){
2281                                 if ((!TypeManager.IsValueType (l) && r == TypeManager.null_type) ||
2282                                     (!TypeManager.IsValueType (r) && l == TypeManager.null_type)) {
2283                                         Type = TypeManager.bool_type;
2284
2285                                         return this;
2286                                 }
2287
2288                                 if (l.IsGenericParameter && (right is NullLiteral)) {
2289                                         if (l.BaseType == TypeManager.value_type) {
2290                                                 Error_OperatorCannotBeApplied ();
2291                                                 return null;
2292                                         }
2293
2294                                         left = new BoxedCast (left);
2295                                         Type = TypeManager.bool_type;
2296                                         return this;
2297                                 }
2298
2299                                 if (r.IsGenericParameter && (left is NullLiteral)) {
2300                                         if (r.BaseType == TypeManager.value_type) {
2301                                                 Error_OperatorCannotBeApplied ();
2302                                                 return null;
2303                                         }
2304
2305                                         right = new BoxedCast (right);
2306                                         Type = TypeManager.bool_type;
2307                                         return this;
2308                                 }
2309
2310                                 // IntPtr equality
2311                                 if (l == TypeManager.intptr_type && r == TypeManager.intptr_type) {
2312                                         Type = TypeManager.bool_type;
2313
2314                                         return this;
2315                                 }
2316                         }
2317
2318                         //
2319                         // Do not perform operator overload resolution when both sides are
2320                         // built-in types
2321                         //
2322                         if (!(TypeManager.IsCLRType (l) && TypeManager.IsCLRType (r))){
2323                                 //
2324                                 // Step 1: Perform Operator Overload location
2325                                 //
2326                                 Expression left_expr, right_expr;
2327
2328                                 string op = oper_names [(int) oper];
2329
2330                                 MethodGroupExpr union;
2331                                 left_expr = MemberLookup (ec, l, op, MemberTypes.Method, AllBindingFlags, loc);
2332                                 if (r != l){
2333                                         right_expr = MemberLookup (
2334                                                 ec, r, op, MemberTypes.Method, AllBindingFlags, loc);
2335                                         union = Invocation.MakeUnionSet (left_expr, right_expr, loc);
2336                                 } else
2337                                         union = (MethodGroupExpr) left_expr;
2338
2339                                 if (union != null) {
2340                                         ArrayList args = new ArrayList (2);
2341                                         args.Add (new Argument (left, Argument.AType.Expression));
2342                                         args.Add (new Argument (right, Argument.AType.Expression));
2343
2344                                         MethodBase method = Invocation.OverloadResolve (
2345                                                 ec, union, args, true, Location.Null);
2346
2347                                         if (method != null) {
2348                                                 MethodInfo mi = (MethodInfo) method;
2349
2350                                                 return new BinaryMethod (mi.ReturnType, method, args);
2351                                         }
2352                                 }
2353                         }
2354
2355                         //
2356                         // Step 0: String concatenation (because overloading will get this wrong)
2357                         //
2358                         if (oper == Operator.Addition){
2359                                 //
2360                                 // If any of the arguments is a string, cast to string
2361                                 //
2362
2363                                 // Simple constant folding
2364                                 if (left is StringConstant && right is StringConstant)
2365                                         return new StringConstant (((StringConstant) left).Value + ((StringConstant) right).Value);
2366
2367                                 if (l == TypeManager.string_type || r == TypeManager.string_type) {
2368
2369                                         if (r == TypeManager.void_type || l == TypeManager.void_type) {
2370                                                 Error_OperatorCannotBeApplied ();
2371                                                 return null;
2372                                         }
2373
2374                                         // try to fold it in on the left
2375                                         if (left is StringConcat) {
2376
2377                                                 //
2378                                                 // We have to test here for not-null, since we can be doubly-resolved
2379                                                 // take care of not appending twice
2380                                                 //
2381                                                 if (type == null){
2382                                                         type = TypeManager.string_type;
2383                                                         ((StringConcat) left).Append (ec, right);
2384                                                         return left.Resolve (ec);
2385                                                 } else {
2386                                                         return left;
2387                                                 }
2388                                         }
2389
2390                                         // Otherwise, start a new concat expression
2391                                         return new StringConcat (ec, loc, left, right).Resolve (ec);
2392                                 }
2393
2394                                 //
2395                                 // Transform a + ( - b) into a - b
2396                                 //
2397                                 if (right is Unary){
2398                                         Unary right_unary = (Unary) right;
2399
2400                                         if (right_unary.Oper == Unary.Operator.UnaryNegation){
2401                                                 oper = Operator.Subtraction;
2402                                                 right = right_unary.Expr;
2403                                                 r = right.Type;
2404                                         }
2405                                 }
2406                         }
2407
2408                         if (oper == Operator.Equality || oper == Operator.Inequality){
2409                                 if (l == TypeManager.bool_type || r == TypeManager.bool_type){
2410                                         if (r != TypeManager.bool_type || l != TypeManager.bool_type){
2411                                                 Error_OperatorCannotBeApplied ();
2412                                                 return null;
2413                                         }
2414
2415                                         type = TypeManager.bool_type;
2416                                         return this;
2417                                 }
2418
2419                                 bool left_is_null = left is NullLiteral;
2420                                 bool right_is_null = right is NullLiteral;
2421                                 if (left_is_null || right_is_null) {
2422                                         if (oper == Operator.Equality)
2423                                                 return new BoolLiteral (left_is_null == right_is_null);
2424                                         else
2425                                                 return new BoolLiteral (left_is_null != right_is_null);
2426                                 }
2427
2428                                 //
2429                                 // operator != (object a, object b)
2430                                 // operator == (object a, object b)
2431                                 //
2432                                 // For this to be used, both arguments have to be reference-types.
2433                                 // Read the rationale on the spec (14.9.6)
2434                                 //
2435                                 // Also, if at compile time we know that the classes do not inherit
2436                                 // one from the other, then we catch the error there.
2437                                 //
2438                                 if (!(l.IsValueType || r.IsValueType)){
2439                                         type = TypeManager.bool_type;
2440
2441                                         if (l == r)
2442                                                 return this;
2443
2444                                         if (l.IsSubclassOf (r) || r.IsSubclassOf (l))
2445                                                 return this;
2446
2447                                         //
2448                                         // Also, a standard conversion must exist from either one
2449                                         //
2450                                         if (!(Convert.ImplicitStandardConversionExists (ec, left, r) ||
2451                                               Convert.ImplicitStandardConversionExists (ec, right, l))){
2452                                                 Error_OperatorCannotBeApplied ();
2453                                                 return null;
2454                                         }
2455                                         //
2456                                         // We are going to have to convert to an object to compare
2457                                         //
2458                                         if (l != TypeManager.object_type)
2459                                                 left = new EmptyCast (left, TypeManager.object_type);
2460                                         if (r != TypeManager.object_type)
2461                                                 right = new EmptyCast (right, TypeManager.object_type);
2462
2463                                         //
2464                                         // FIXME: CSC here catches errors cs254 and cs252
2465                                         //
2466                                         return this;
2467                                 }
2468
2469                                 //
2470                                 // One of them is a valuetype, but the other one is not.
2471                                 //
2472                                 if (!l.IsValueType || !r.IsValueType) {
2473                                         Error_OperatorCannotBeApplied ();
2474                                         return null;
2475                                 }
2476                         }
2477
2478                         // Only perform numeric promotions on:
2479                         // +, -, *, /, %, &, |, ^, ==, !=, <, >, <=, >=
2480                         //
2481                         if (oper == Operator.Addition || oper == Operator.Subtraction) {
2482                                 if (TypeManager.IsDelegateType (l)){
2483                                         if (((right.eclass == ExprClass.MethodGroup) ||
2484                                              (r == TypeManager.anonymous_method_type))){
2485                                                 if ((RootContext.Version != LanguageVersion.ISO_1)){
2486                                                         Expression tmp = Convert.ImplicitConversionRequired (ec, right, l, loc);
2487                                                         if (tmp == null)
2488                                                                 return null;
2489                                                         right = tmp;
2490                                                         r = right.Type;
2491                                                 }
2492                                         }
2493
2494                                         if (TypeManager.IsDelegateType (r)){
2495                                                 MethodInfo method;
2496                                                 ArrayList args = new ArrayList (2);
2497
2498                                                 args = new ArrayList (2);
2499                                                 args.Add (new Argument (left, Argument.AType.Expression));
2500                                                 args.Add (new Argument (right, Argument.AType.Expression));
2501
2502                                                 if (oper == Operator.Addition)
2503                                                         method = TypeManager.delegate_combine_delegate_delegate;
2504                                                 else
2505                                                         method = TypeManager.delegate_remove_delegate_delegate;
2506
2507                                                 if (!TypeManager.IsEqual (l, r)) {
2508                                                         Error_OperatorCannotBeApplied ();
2509                                                         return null;
2510                                                 }
2511
2512                                                 return new BinaryDelegate (l, method, args);
2513                                         }
2514                                 }
2515
2516                                 //
2517                                 // Pointer arithmetic:
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                                 // T* operator + (int y,   T* x);
2525                                 // T* operator + (uint y,  T *x);
2526                                 // T* operator + (long y,  T *x);
2527                                 // T* operator + (ulong y, T *x);
2528                                 //
2529                                 // T* operator - (T* x, int y);
2530                                 // T* operator - (T* x, uint y);
2531                                 // T* operator - (T* x, long y);
2532                                 // T* operator - (T* x, ulong y);
2533                                 //
2534                                 // long operator - (T* x, T *y)
2535                                 //
2536                                 if (l.IsPointer){
2537                                         if (r.IsPointer && oper == Operator.Subtraction){
2538                                                 if (r == l)
2539                                                         return new PointerArithmetic (
2540                                                                 false, left, right, TypeManager.int64_type,
2541                                                                 loc).Resolve (ec);
2542                                         } else {
2543                                                 Expression t = Make32or64 (ec, right);
2544                                                 if (t != null)
2545                                                         return new PointerArithmetic (oper == Operator.Addition, left, t, l, loc).Resolve (ec);
2546                                         }
2547                                 } else if (r.IsPointer && oper == Operator.Addition){
2548                                         Expression t = Make32or64 (ec, left);
2549                                         if (t != null)
2550                                                 return new PointerArithmetic (true, right, t, r, loc).Resolve (ec);
2551                                 }
2552                         }
2553
2554                         //
2555                         // Enumeration operators
2556                         //
2557                         bool lie = TypeManager.IsEnumType (l);
2558                         bool rie = TypeManager.IsEnumType (r);
2559                         if (lie || rie){
2560                                 Expression temp;
2561
2562                                 // U operator - (E e, E f)
2563                                 if (lie && rie){
2564                                         if (oper == Operator.Subtraction){
2565                                         if (l == r){
2566                                                 type = TypeManager.EnumToUnderlying (l);
2567                                                 return this;
2568                                         }
2569                                         Error_OperatorCannotBeApplied ();
2570                                         return null;
2571                                 }
2572                                 }
2573
2574                                 //
2575                                 // operator + (E e, U x)
2576                                 // operator - (E e, U x)
2577                                 //
2578                                 if (oper == Operator.Addition || oper == Operator.Subtraction){
2579                                         Type enum_type = lie ? l : r;
2580                                         Type other_type = lie ? r : l;
2581                                         Type underlying_type = TypeManager.EnumToUnderlying (enum_type);
2582
2583                                         if (underlying_type != other_type){
2584                                                 temp = Convert.ImplicitConversion (ec, lie ? right : left, underlying_type, loc);
2585                                                 if (temp != null){
2586                                                         if (lie)
2587                                                                 right = temp;
2588                                                         else
2589                                                                 left = temp;
2590                                                         type = enum_type;
2591                                                         return this;
2592                                                 }
2593
2594                                                 Error_OperatorCannotBeApplied ();
2595                                                 return null;
2596                                         }
2597
2598                                         type = enum_type;
2599                                         return this;
2600                                 }
2601
2602                                 if (!rie){
2603                                         temp = Convert.ImplicitConversion (ec, right, l, loc);
2604                                         if (temp != null)
2605                                                 right = temp;
2606                                         else {
2607                                                 Error_OperatorCannotBeApplied ();
2608                                                 return null;
2609                                         }
2610                                 } if (!lie){
2611                                         temp = Convert.ImplicitConversion (ec, left, r, loc);
2612                                         if (temp != null){
2613                                                 left = temp;
2614                                                 l = r;
2615                                         } else {
2616                                                 Error_OperatorCannotBeApplied ();
2617                                                 return null;
2618                                         }
2619                                 }
2620
2621                                 if (oper == Operator.Equality || oper == Operator.Inequality ||
2622                                     oper == Operator.LessThanOrEqual || oper == Operator.LessThan ||
2623                                     oper == Operator.GreaterThanOrEqual || oper == Operator.GreaterThan){
2624                                         if (left.Type != right.Type){
2625                                                 Error_OperatorCannotBeApplied ();
2626                                                 return null;
2627                                         }
2628                                         type = TypeManager.bool_type;
2629                                         return this;
2630                                 }
2631
2632                                 if (oper == Operator.BitwiseAnd ||
2633                                     oper == Operator.BitwiseOr ||
2634                                     oper == Operator.ExclusiveOr){
2635                                         type = l;
2636                                         return this;
2637                                 }
2638                                 Error_OperatorCannotBeApplied ();
2639                                 return null;
2640                         }
2641
2642                         if (oper == Operator.LeftShift || oper == Operator.RightShift)
2643                                 return CheckShiftArguments (ec);
2644
2645                         if (oper == Operator.LogicalOr || oper == Operator.LogicalAnd){
2646                                 if (l == TypeManager.bool_type && r == TypeManager.bool_type) {
2647                                         type = TypeManager.bool_type;
2648                                         return this;
2649                                 }
2650
2651                                 if (l != r) {
2652                                         Error_OperatorCannotBeApplied ();
2653                                         return null;
2654                                 }
2655
2656                                 Expression e = new ConditionalLogicalOperator (
2657                                         oper == Operator.LogicalAnd, left, right, l, loc);
2658                                 return e.Resolve (ec);
2659                         }
2660
2661                         //
2662                         // operator & (bool x, bool y)
2663                         // operator | (bool x, bool y)
2664                         // operator ^ (bool x, bool y)
2665                         //
2666                         if (l == TypeManager.bool_type && r == TypeManager.bool_type){
2667                                 if (oper == Operator.BitwiseAnd ||
2668                                     oper == Operator.BitwiseOr ||
2669                                     oper == Operator.ExclusiveOr){
2670                                         type = l;
2671                                         return this;
2672                                 }
2673                         }
2674
2675                         //
2676                         // Pointer comparison
2677                         //
2678                         if (l.IsPointer && r.IsPointer){
2679                                 if (oper == Operator.Equality || oper == Operator.Inequality ||
2680                                     oper == Operator.LessThan || oper == Operator.LessThanOrEqual ||
2681                                     oper == Operator.GreaterThan || oper == Operator.GreaterThanOrEqual){
2682                                         type = TypeManager.bool_type;
2683                                         return this;
2684                                 }
2685                         }
2686
2687                         //
2688                         // This will leave left or right set to null if there is an error
2689                         //
2690                         bool check_user_conv = is_user_defined (l) && is_user_defined (r);
2691                         DoNumericPromotions (ec, l, r, check_user_conv);
2692                         if (left == null || right == null){
2693                                 Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
2694                                 return null;
2695                         }
2696
2697                         //
2698                         // reload our cached types if required
2699                         //
2700                         l = left.Type;
2701                         r = right.Type;
2702
2703                         if (oper == Operator.BitwiseAnd ||
2704                             oper == Operator.BitwiseOr ||
2705                             oper == Operator.ExclusiveOr){
2706                                 if (l == r){
2707                                         if (((l == TypeManager.int32_type) ||
2708                                              (l == TypeManager.uint32_type) ||
2709                                              (l == TypeManager.short_type) ||
2710                                              (l == TypeManager.ushort_type) ||
2711                                              (l == TypeManager.int64_type) ||
2712                                              (l == TypeManager.uint64_type))){
2713                                                 type = l;
2714                                         } else {
2715                                                 Error_OperatorCannotBeApplied ();
2716                                                 return null;
2717                                         }
2718                                 } else {
2719                                         Error_OperatorCannotBeApplied ();
2720                                         return null;
2721                                 }
2722                         }
2723
2724                         if (oper == Operator.Equality ||
2725                             oper == Operator.Inequality ||
2726                             oper == Operator.LessThanOrEqual ||
2727                             oper == Operator.LessThan ||
2728                             oper == Operator.GreaterThanOrEqual ||
2729                             oper == Operator.GreaterThan){
2730                                 type = TypeManager.bool_type;
2731                         }
2732
2733                         return this;
2734                 }
2735
2736                 public override Expression DoResolve (EmitContext ec)
2737                 {
2738                         if ((oper == Operator.Subtraction) && (left is ParenthesizedExpression)) {
2739                                 left = ((ParenthesizedExpression) left).Expr;
2740                                 left = left.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.Type);
2741                                 if (left == null)
2742                                         return null;
2743
2744                                 if (left.eclass == ExprClass.Type) {
2745                                         Error (75, "Casting a negative value needs to have the value in parentheses.");
2746                                         return null;
2747                                 }
2748                         } else
2749                                 left = left.Resolve (ec);
2750
2751                         if (left == null)
2752                                 return null;
2753
2754                         Constant lc = left as Constant;
2755                         if (lc != null && lc.Type == TypeManager.bool_type &&
2756                                 ((oper == Operator.LogicalAnd && (bool)lc.GetValue () == false) ||
2757                                  (oper == Operator.LogicalOr && (bool)lc.GetValue () == true))) {
2758
2759                                 // TODO: make a sense to resolve unreachable expression as we do for statement
2760                                 Report.Warning (429, 4, loc, "Unreachable expression code detected");
2761                                 return left;
2762                         }
2763
2764                         right = right.Resolve (ec);
2765                         if (right == null)
2766                                 return null;
2767
2768                         eclass = ExprClass.Value;
2769
2770                         Constant rc = right as Constant;
2771                         if (rc != null & lc != null){
2772                                 Expression e = ConstantFold.BinaryFold (
2773                                         ec, oper, lc, rc, loc);
2774                                         if (e != null)
2775                                                 return e;
2776                         }
2777
2778                         if (TypeManager.IsNullableType (left.Type) || TypeManager.IsNullableType (right.Type))
2779                                 return new Nullable.LiftedBinaryOperator (oper, left, right, loc).Resolve (ec);
2780
2781                         return ResolveOperator (ec);
2782                 }
2783
2784                 /// <remarks>
2785                 ///   EmitBranchable is called from Statement.EmitBoolExpression in the
2786                 ///   context of a conditional bool expression.  This function will return
2787                 ///   false if it is was possible to use EmitBranchable, or true if it was.
2788                 ///
2789                 ///   The expression's code is generated, and we will generate a branch to `target'
2790                 ///   if the resulting expression value is equal to isTrue
2791                 /// </remarks>
2792                 public override void EmitBranchable (EmitContext ec, Label target, bool onTrue)
2793                 {
2794                         ILGenerator ig = ec.ig;
2795
2796                         //
2797                         // This is more complicated than it looks, but its just to avoid
2798                         // duplicated tests: basically, we allow ==, !=, >, <, >= and <=
2799                         // but on top of that we want for == and != to use a special path
2800                         // if we are comparing against null
2801                         //
2802                         if ((oper == Operator.Equality || oper == Operator.Inequality) && (left is Constant || right is Constant)) {
2803                                 bool my_on_true = oper == Operator.Inequality ? onTrue : !onTrue;
2804
2805                                 //
2806                                 // put the constant on the rhs, for simplicity
2807                                 //
2808                                 if (left is Constant) {
2809                                         Expression swap = right;
2810                                         right = left;
2811                                         left = swap;
2812                                 }
2813
2814                                 if (((Constant) right).IsZeroInteger) {
2815                                         left.Emit (ec);
2816                                         if (my_on_true)
2817                                                 ig.Emit (OpCodes.Brtrue, target);
2818                                         else
2819                                                 ig.Emit (OpCodes.Brfalse, target);
2820
2821                                         return;
2822                                 } else if (right is BoolConstant){
2823                                         left.Emit (ec);
2824                                         if (my_on_true != ((BoolConstant) right).Value)
2825                                                 ig.Emit (OpCodes.Brtrue, target);
2826                                         else
2827                                                 ig.Emit (OpCodes.Brfalse, target);
2828
2829                                         return;
2830                                 }
2831
2832                         } else if (oper == Operator.LogicalAnd) {
2833
2834                                 if (onTrue) {
2835                                                 Label tests_end = ig.DefineLabel ();
2836
2837                                         left.EmitBranchable (ec, tests_end, false);
2838                                         right.EmitBranchable (ec, target, true);
2839                                                         ig.MarkLabel (tests_end);
2840                                         } else {
2841                                         left.EmitBranchable (ec, target, false);
2842                                         right.EmitBranchable (ec, target, false);
2843                                         }
2844
2845                                 return;
2846
2847                         } else if (oper == Operator.LogicalOr){
2848                                 if (onTrue) {
2849                                         left.EmitBranchable (ec, target, true);
2850                                         right.EmitBranchable (ec, target, true);
2851
2852                                         } else {
2853                                                 Label tests_end = ig.DefineLabel ();
2854                                         left.EmitBranchable (ec, tests_end, true);
2855                                         right.EmitBranchable (ec, target, false);
2856                                         ig.MarkLabel (tests_end);
2857                                 }
2858
2859                                 return;
2860
2861                         } else if (!(oper == Operator.LessThan        || oper == Operator.GreaterThan ||
2862                                      oper == Operator.LessThanOrEqual || oper == Operator.GreaterThanOrEqual ||
2863                                      oper == Operator.Equality        || oper == Operator.Inequality)) {
2864                                 base.EmitBranchable (ec, target, onTrue);
2865                                 return;
2866                                 }
2867
2868                         left.Emit (ec);
2869                         right.Emit (ec);
2870
2871                         Type t = left.Type;
2872                         bool isUnsigned = is_unsigned (t) || t == TypeManager.double_type || t == TypeManager.float_type;
2873
2874                         switch (oper){
2875                         case Operator.Equality:
2876                                 if (onTrue)
2877                                         ig.Emit (OpCodes.Beq, target);
2878                                 else
2879                                         ig.Emit (OpCodes.Bne_Un, target);
2880                                 break;
2881
2882                         case Operator.Inequality:
2883                                 if (onTrue)
2884                                         ig.Emit (OpCodes.Bne_Un, target);
2885                                 else
2886                                         ig.Emit (OpCodes.Beq, target);
2887                                 break;
2888
2889                         case Operator.LessThan:
2890                                 if (onTrue)
2891                                         if (isUnsigned)
2892                                                 ig.Emit (OpCodes.Blt_Un, target);
2893                                         else
2894                                                 ig.Emit (OpCodes.Blt, target);
2895                                 else
2896                                         if (isUnsigned)
2897                                                 ig.Emit (OpCodes.Bge_Un, target);
2898                                         else
2899                                                 ig.Emit (OpCodes.Bge, target);
2900                                 break;
2901
2902                         case Operator.GreaterThan:
2903                                 if (onTrue)
2904                                         if (isUnsigned)
2905                                                 ig.Emit (OpCodes.Bgt_Un, target);
2906                                         else
2907                                                 ig.Emit (OpCodes.Bgt, target);
2908                                 else
2909                                         if (isUnsigned)
2910                                                 ig.Emit (OpCodes.Ble_Un, target);
2911                                         else
2912                                                 ig.Emit (OpCodes.Ble, target);
2913                                 break;
2914
2915                         case Operator.LessThanOrEqual:
2916                                 if (onTrue)
2917                                         if (isUnsigned)
2918                                                 ig.Emit (OpCodes.Ble_Un, target);
2919                                         else
2920                                                 ig.Emit (OpCodes.Ble, target);
2921                                 else
2922                                         if (isUnsigned)
2923                                                 ig.Emit (OpCodes.Bgt_Un, target);
2924                                         else
2925                                                 ig.Emit (OpCodes.Bgt, target);
2926                                 break;
2927
2928
2929                         case Operator.GreaterThanOrEqual:
2930                                 if (onTrue)
2931                                         if (isUnsigned)
2932                                                 ig.Emit (OpCodes.Bge_Un, target);
2933                                         else
2934                                                 ig.Emit (OpCodes.Bge, target);
2935                                 else
2936                                         if (isUnsigned)
2937                                                 ig.Emit (OpCodes.Blt_Un, target);
2938                                         else
2939                                                 ig.Emit (OpCodes.Blt, target);
2940                                 break;
2941                         default:
2942                                 Console.WriteLine (oper);
2943                                 throw new Exception ("what is THAT");
2944                         }
2945                 }
2946
2947                 public override void Emit (EmitContext ec)
2948                 {
2949                         ILGenerator ig = ec.ig;
2950                         Type l = left.Type;
2951                         OpCode opcode;
2952
2953                         //
2954                         // Handle short-circuit operators differently
2955                         // than the rest
2956                         //
2957                         if (oper == Operator.LogicalAnd) {
2958                                 Label load_zero = ig.DefineLabel ();
2959                                 Label end = ig.DefineLabel ();
2960
2961                                 left.EmitBranchable (ec, load_zero, false);
2962                                                 right.Emit (ec);
2963                                                 ig.Emit (OpCodes.Br, end);
2964
2965                                 ig.MarkLabel (load_zero);
2966                                 ig.Emit (OpCodes.Ldc_I4_0);
2967                                 ig.MarkLabel (end);
2968                                 return;
2969                         } else if (oper == Operator.LogicalOr) {
2970                                 Label load_one = ig.DefineLabel ();
2971                                 Label end = ig.DefineLabel ();
2972
2973                                 left.EmitBranchable (ec, load_one, true);
2974                                                 right.Emit (ec);
2975                                                 ig.Emit (OpCodes.Br, end);
2976
2977                                 ig.MarkLabel (load_one);
2978                                 ig.Emit (OpCodes.Ldc_I4_1);
2979                                 ig.MarkLabel (end);
2980                                 return;
2981                         }
2982
2983                         left.Emit (ec);
2984                         right.Emit (ec);
2985
2986                         bool isUnsigned = is_unsigned (left.Type);
2987
2988                         switch (oper){
2989                         case Operator.Multiply:
2990                                 if (ec.CheckState){
2991                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
2992                                                 opcode = OpCodes.Mul_Ovf;
2993                                         else if (isUnsigned)
2994                                                 opcode = OpCodes.Mul_Ovf_Un;
2995                                         else
2996                                                 opcode = OpCodes.Mul;
2997                                 } else
2998                                         opcode = OpCodes.Mul;
2999
3000                                 break;
3001
3002                         case Operator.Division:
3003                                 if (isUnsigned)
3004                                         opcode = OpCodes.Div_Un;
3005                                 else
3006                                         opcode = OpCodes.Div;
3007                                 break;
3008
3009                         case Operator.Modulus:
3010                                 if (isUnsigned)
3011                                         opcode = OpCodes.Rem_Un;
3012                                 else
3013                                         opcode = OpCodes.Rem;
3014                                 break;
3015
3016                         case Operator.Addition:
3017                                 if (ec.CheckState){
3018                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
3019                                                 opcode = OpCodes.Add_Ovf;
3020                                         else if (isUnsigned)
3021                                                 opcode = OpCodes.Add_Ovf_Un;
3022                                         else
3023                                                 opcode = OpCodes.Add;
3024                                 } else
3025                                         opcode = OpCodes.Add;
3026                                 break;
3027
3028                         case Operator.Subtraction:
3029                                 if (ec.CheckState){
3030                                         if (l == TypeManager.int32_type || l == TypeManager.int64_type)
3031                                                 opcode = OpCodes.Sub_Ovf;
3032                                         else if (isUnsigned)
3033                                                 opcode = OpCodes.Sub_Ovf_Un;
3034                                         else
3035                                                 opcode = OpCodes.Sub;
3036                                 } else
3037                                         opcode = OpCodes.Sub;
3038                                 break;
3039
3040                         case Operator.RightShift:
3041                                 if (isUnsigned)
3042                                         opcode = OpCodes.Shr_Un;
3043                                 else
3044                                         opcode = OpCodes.Shr;
3045                                 break;
3046
3047                         case Operator.LeftShift:
3048                                 opcode = OpCodes.Shl;
3049                                 break;
3050
3051                         case Operator.Equality:
3052                                 opcode = OpCodes.Ceq;
3053                                 break;
3054
3055                         case Operator.Inequality:
3056                                 ig.Emit (OpCodes.Ceq);
3057                                 ig.Emit (OpCodes.Ldc_I4_0);
3058
3059                                 opcode = OpCodes.Ceq;
3060                                 break;
3061
3062                         case Operator.LessThan:
3063                                 if (isUnsigned)
3064                                         opcode = OpCodes.Clt_Un;
3065                                 else
3066                                         opcode = OpCodes.Clt;
3067                                 break;
3068
3069                         case Operator.GreaterThan:
3070                                 if (isUnsigned)
3071                                         opcode = OpCodes.Cgt_Un;
3072                                 else
3073                                         opcode = OpCodes.Cgt;
3074                                 break;
3075
3076                         case Operator.LessThanOrEqual:
3077                                 Type lt = left.Type;
3078
3079                                 if (isUnsigned || (lt == TypeManager.double_type || lt == TypeManager.float_type))
3080                                         ig.Emit (OpCodes.Cgt_Un);
3081                                 else
3082                                         ig.Emit (OpCodes.Cgt);
3083                                 ig.Emit (OpCodes.Ldc_I4_0);
3084
3085                                 opcode = OpCodes.Ceq;
3086                                 break;
3087
3088                         case Operator.GreaterThanOrEqual:
3089                                 Type le = left.Type;
3090
3091                                 if (isUnsigned || (le == TypeManager.double_type || le == TypeManager.float_type))
3092                                         ig.Emit (OpCodes.Clt_Un);
3093                                 else
3094                                         ig.Emit (OpCodes.Clt);
3095
3096                                 ig.Emit (OpCodes.Ldc_I4_0);
3097
3098                                 opcode = OpCodes.Ceq;
3099                                 break;
3100
3101                         case Operator.BitwiseOr:
3102                                 opcode = OpCodes.Or;
3103                                 break;
3104
3105                         case Operator.BitwiseAnd:
3106                                 opcode = OpCodes.And;
3107                                 break;
3108
3109                         case Operator.ExclusiveOr:
3110                                 opcode = OpCodes.Xor;
3111                                 break;
3112
3113                         default:
3114                                 throw new Exception ("This should not happen: Operator = "
3115                                                      + oper.ToString ());
3116                         }
3117
3118                         ig.Emit (opcode);
3119                 }
3120         }
3121
3122         //
3123         // Object created by Binary when the binary operator uses an method instead of being
3124         // a binary operation that maps to a CIL binary operation.
3125         //
3126         public class BinaryMethod : Expression {
3127                 public MethodBase method;
3128                 public ArrayList  Arguments;
3129
3130                 public BinaryMethod (Type t, MethodBase m, ArrayList args)
3131                 {
3132                         method = m;
3133                         Arguments = args;
3134                         type = t;
3135                         eclass = ExprClass.Value;
3136                 }
3137
3138                 public override Expression DoResolve (EmitContext ec)
3139                 {
3140                         return this;
3141                 }
3142
3143                 public override void Emit (EmitContext ec)
3144                 {
3145                         ILGenerator ig = ec.ig;
3146
3147                         if (Arguments != null)
3148                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
3149
3150                         if (method is MethodInfo)
3151                                 ig.Emit (OpCodes.Call, (MethodInfo) method);
3152                         else
3153                                 ig.Emit (OpCodes.Call, (ConstructorInfo) method);
3154                 }
3155         }
3156
3157         //
3158         // Represents the operation a + b [+ c [+ d [+ ...]]], where a is a string
3159         // b, c, d... may be strings or objects.
3160         //
3161         public class StringConcat : Expression {
3162                 ArrayList operands;
3163                 bool invalid = false;
3164                 bool emit_conv_done = false;
3165                 //
3166                 // Are we also concating objects?
3167                 //
3168                 bool is_strings_only = true;
3169
3170                 public StringConcat (EmitContext ec, Location loc, Expression left, Expression right)
3171                 {
3172                         this.loc = loc;
3173                         type = TypeManager.string_type;
3174                         eclass = ExprClass.Value;
3175
3176                         operands = new ArrayList (2);
3177                         Append (ec, left);
3178                         Append (ec, right);
3179                 }
3180
3181                 public override Expression DoResolve (EmitContext ec)
3182                 {
3183                         if (invalid)
3184                                 return null;
3185
3186                         return this;
3187                 }
3188
3189                 public void Append (EmitContext ec, Expression operand)
3190                 {
3191                         //
3192                         // Constant folding
3193                         //
3194                         if (operand is StringConstant && operands.Count != 0) {
3195                                 StringConstant last_operand = operands [operands.Count - 1] as StringConstant;
3196                                 if (last_operand != null) {
3197                                         operands [operands.Count - 1] = new StringConstant (last_operand.Value + ((StringConstant) operand).Value);
3198                                         return;
3199                                 }
3200                         }
3201
3202                         //
3203                         // Conversion to object
3204                         //
3205                         if (operand.Type != TypeManager.string_type) {
3206                                 Expression no = Convert.ImplicitConversion (ec, operand, TypeManager.object_type, loc);
3207
3208                                 if (no == null) {
3209                                         Binary.Error_OperatorCannotBeApplied (loc, "+", TypeManager.string_type, operand.Type);
3210                                         invalid = true;
3211                                 }
3212                                 operand = no;
3213                         }
3214
3215                         operands.Add (operand);
3216                 }
3217
3218                 public override void Emit (EmitContext ec)
3219                 {
3220                         MethodInfo concat_method = null;
3221
3222                         //
3223                         // Do conversion to arguments; check for strings only
3224                         //
3225
3226                         // This can get called multiple times, so we have to deal with that.
3227                         if (!emit_conv_done) {
3228                                 emit_conv_done = true;
3229                         for (int i = 0; i < operands.Count; i ++) {
3230                                 Expression e = (Expression) operands [i];
3231                                 is_strings_only &= e.Type == TypeManager.string_type;
3232                         }
3233
3234                         for (int i = 0; i < operands.Count; i ++) {
3235                                 Expression e = (Expression) operands [i];
3236
3237                                 if (! is_strings_only && e.Type == TypeManager.string_type) {
3238                                         // need to make sure this is an object, because the EmitParams
3239                                         // method might look at the type of this expression, see it is a
3240                                         // string and emit a string [] when we want an object [];
3241
3242                                                 e = new EmptyCast (e, TypeManager.object_type);
3243                                 }
3244                                 operands [i] = new Argument (e, Argument.AType.Expression);
3245                         }
3246                         }
3247
3248                         //
3249                         // Find the right method
3250                         //
3251                         switch (operands.Count) {
3252                         case 1:
3253                                 //
3254                                 // This should not be possible, because simple constant folding
3255                                 // is taken care of in the Binary code.
3256                                 //
3257                                 throw new Exception ("how did you get here?");
3258
3259                         case 2:
3260                                 concat_method = is_strings_only ?
3261                                         TypeManager.string_concat_string_string :
3262                                         TypeManager.string_concat_object_object ;
3263                                 break;
3264                         case 3:
3265                                 concat_method = is_strings_only ?
3266                                         TypeManager.string_concat_string_string_string :
3267                                         TypeManager.string_concat_object_object_object ;
3268                                 break;
3269                         case 4:
3270                                 //
3271                                 // There is not a 4 param overlaod for object (the one that there is
3272                                 // is actually a varargs methods, and is only in corlib because it was
3273                                 // introduced there before.).
3274                                 //
3275                                 if (!is_strings_only)
3276                                         goto default;
3277
3278                                 concat_method = TypeManager.string_concat_string_string_string_string;
3279                                 break;
3280                         default:
3281                                 concat_method = is_strings_only ?
3282                                         TypeManager.string_concat_string_dot_dot_dot :
3283                                         TypeManager.string_concat_object_dot_dot_dot ;
3284                                 break;
3285                         }
3286
3287                         Invocation.EmitArguments (ec, concat_method, operands, false, null);
3288                         ec.ig.Emit (OpCodes.Call, concat_method);
3289                 }
3290         }
3291
3292         //
3293         // Object created with +/= on delegates
3294         //
3295         public class BinaryDelegate : Expression {
3296                 MethodInfo method;
3297                 ArrayList  args;
3298
3299                 public BinaryDelegate (Type t, MethodInfo mi, ArrayList args)
3300                 {
3301                         method = mi;
3302                         this.args = args;
3303                         type = t;
3304                         eclass = ExprClass.Value;
3305                 }
3306
3307                 public override Expression DoResolve (EmitContext ec)
3308                 {
3309                         return this;
3310                 }
3311
3312                 public override void Emit (EmitContext ec)
3313                 {
3314                         ILGenerator ig = ec.ig;
3315
3316                         Invocation.EmitArguments (ec, method, args, false, null);
3317
3318                         ig.Emit (OpCodes.Call, (MethodInfo) method);
3319                         ig.Emit (OpCodes.Castclass, type);
3320                 }
3321
3322                 public Expression Right {
3323                         get {
3324                                 Argument arg = (Argument) args [1];
3325                                 return arg.Expr;
3326                         }
3327                 }
3328
3329                 public bool IsAddition {
3330                         get {
3331                                 return method == TypeManager.delegate_combine_delegate_delegate;
3332                         }
3333                 }
3334         }
3335
3336         //
3337         // User-defined conditional logical operator
3338         public class ConditionalLogicalOperator : Expression {
3339                 Expression left, right;
3340                 bool is_and;
3341
3342                 public ConditionalLogicalOperator (bool is_and, Expression left, Expression right, Type t, Location loc)
3343                 {
3344                         type = t;
3345                         eclass = ExprClass.Value;
3346                         this.loc = loc;
3347                         this.left = left;
3348                         this.right = right;
3349                         this.is_and = is_and;
3350                 }
3351
3352                 protected void Error19 ()
3353                 {
3354                         Binary.Error_OperatorCannotBeApplied (loc, is_and ? "&&" : "||", type, type);
3355                 }
3356
3357                 protected void Error218 ()
3358                 {
3359                         Error (218, "The type ('" + TypeManager.CSharpName (type) + "') must contain " +
3360                                "declarations of operator true and operator false");
3361                 }
3362
3363                 Expression op_true, op_false, op;
3364                 LocalTemporary left_temp;
3365
3366                 public override Expression DoResolve (EmitContext ec)
3367                 {
3368                         MethodInfo method;
3369                         Expression operator_group;
3370
3371                         operator_group = MethodLookup (ec, type, is_and ? "op_BitwiseAnd" : "op_BitwiseOr", loc);
3372                         if (operator_group == null) {
3373                                 Error19 ();
3374                                 return null;
3375                         }
3376
3377                         left_temp = new LocalTemporary (ec, type);
3378
3379                         ArrayList arguments = new ArrayList ();
3380                         arguments.Add (new Argument (left_temp, Argument.AType.Expression));
3381                         arguments.Add (new Argument (right, Argument.AType.Expression));
3382                         method = Invocation.OverloadResolve (
3383                                 ec, (MethodGroupExpr) operator_group, arguments, false, loc)
3384                                 as MethodInfo;
3385                         if ((method == null) || (method.ReturnType != type)) {
3386                                 Error19 ();
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                         Type element = TypeManager.GetElementType (op_type);
3453                         int size = GetTypeSize (element);
3454                         Type rtype = right.Type;
3455
3456                         if (rtype.IsPointer){
3457                                 //
3458                                 // handle (pointer - pointer)
3459                                 //
3460                                 left.Emit (ec);
3461                                 right.Emit (ec);
3462                                 ig.Emit (OpCodes.Sub);
3463
3464                                 if (size != 1){
3465                                         if (size == 0)
3466                                                 ig.Emit (OpCodes.Sizeof, element);
3467                                         else
3468                                                 IntLiteral.EmitInt (ig, size);
3469                                         ig.Emit (OpCodes.Div);
3470                                 }
3471                                 ig.Emit (OpCodes.Conv_I8);
3472                         } else {
3473                                 //
3474                                 // handle + and - on (pointer op int)
3475                                 //
3476                                 left.Emit (ec);
3477                                 ig.Emit (OpCodes.Conv_I);
3478
3479                                 Constant right_const = right as Constant;
3480                                 if (right_const != null && size != 0) {
3481                                         Expression ex = ConstantFold.BinaryFold (ec, Binary.Operator.Multiply, new IntConstant (size), right_const, loc);
3482                                         if (ex == null)
3483                                                 return;
3484                                         ex.Emit (ec);
3485                                 } else {
3486                                         right.Emit (ec);
3487                                         if (size != 1){
3488                                                 if (size == 0)
3489                                                         ig.Emit (OpCodes.Sizeof, element);
3490                                                 else
3491                                                         IntLiteral.EmitInt (ig, size);
3492                                                 if (rtype == TypeManager.int64_type)
3493                                                         ig.Emit (OpCodes.Conv_I8);
3494                                                 else if (rtype == TypeManager.uint64_type)
3495                                                         ig.Emit (OpCodes.Conv_U8);
3496                                                 ig.Emit (OpCodes.Mul);
3497                                         }
3498                                 }
3499
3500                                 if (rtype == TypeManager.int64_type || rtype == TypeManager.uint64_type)
3501                                         ig.Emit (OpCodes.Conv_I);
3502
3503                                 if (is_add)
3504                                         ig.Emit (OpCodes.Add);
3505                                 else
3506                                         ig.Emit (OpCodes.Sub);
3507                         }
3508                 }
3509         }
3510
3511         /// <summary>
3512         ///   Implements the ternary conditional operator (?:)
3513         /// </summary>
3514         public class Conditional : Expression {
3515                 Expression expr, trueExpr, falseExpr;
3516
3517                 public Conditional (Expression expr, Expression trueExpr, Expression falseExpr, Location l)
3518                 {
3519                         this.expr = expr;
3520                         this.trueExpr = trueExpr;
3521                         this.falseExpr = falseExpr;
3522                         this.loc = l;
3523                 }
3524
3525                 public Expression Expr {
3526                         get {
3527                                 return expr;
3528                         }
3529                 }
3530
3531                 public Expression TrueExpr {
3532                         get {
3533                                 return trueExpr;
3534                         }
3535                 }
3536
3537                 public Expression FalseExpr {
3538                         get {
3539                                 return falseExpr;
3540                         }
3541                 }
3542
3543                 public override Expression DoResolve (EmitContext ec)
3544                 {
3545                         expr = expr.Resolve (ec);
3546
3547                         if (expr == null)
3548                                 return null;
3549
3550                         if (TypeManager.IsNullableType (expr.Type))
3551                                 return new Nullable.LiftedConditional (expr, trueExpr, falseExpr, loc).Resolve (ec);
3552
3553                         if (expr.Type != TypeManager.bool_type){
3554                                 expr = Expression.ResolveBoolean (
3555                                         ec, expr, loc);
3556
3557                                 if (expr == null)
3558                                         return null;
3559                         }
3560
3561                         trueExpr = trueExpr.Resolve (ec);
3562                         falseExpr = falseExpr.Resolve (ec);
3563
3564                         if (trueExpr == null || falseExpr == null)
3565                                 return null;
3566
3567                         eclass = ExprClass.Value;
3568                         if (trueExpr.Type == falseExpr.Type)
3569                                 type = trueExpr.Type;
3570                         else {
3571                                 Expression conv;
3572                                 Type true_type = trueExpr.Type;
3573                                 Type false_type = falseExpr.Type;
3574
3575                                 //
3576                                 // First, if an implicit conversion exists from trueExpr
3577                                 // to falseExpr, then the result type is of type falseExpr.Type
3578                                 //
3579                                 conv = Convert.ImplicitConversion (ec, trueExpr, false_type, loc);
3580                                 if (conv != null){
3581                                         //
3582                                         // Check if both can convert implicitl to each other's type
3583                                         //
3584                                         if (Convert.ImplicitConversion (ec, falseExpr, true_type, loc) != null){
3585                                                 Error (172,
3586                                                        "Can not compute type of conditional expression " +
3587                                                        "as `" + TypeManager.CSharpName (trueExpr.Type) +
3588                                                        "' and `" + TypeManager.CSharpName (falseExpr.Type) +
3589                                                        "' convert implicitly to each other");
3590                                                 return null;
3591                                         }
3592                                         type = false_type;
3593                                         trueExpr = conv;
3594                                 } else if ((conv = Convert.ImplicitConversion(ec, falseExpr, true_type,loc))!= null){
3595                                         type = true_type;
3596                                         falseExpr = conv;
3597                                 } else {
3598                                         Error (173, "The type of the conditional expression can " +
3599                                                "not be computed because there is no implicit conversion" +
3600                                                " from `" + TypeManager.CSharpName (trueExpr.Type) + "'" +
3601                                                " and `" + TypeManager.CSharpName (falseExpr.Type) + "'");
3602                                         return null;
3603                                 }
3604                         }
3605
3606                         // Dead code optimalization
3607                         if (expr is BoolConstant){
3608                                 BoolConstant bc = (BoolConstant) expr;
3609
3610                                 Report.Warning (429, 4, bc.Value ? falseExpr.Location : trueExpr.Location, "Unreachable expression code detected");
3611                                 return bc.Value ? trueExpr : falseExpr;
3612                         }
3613
3614                         return this;
3615                 }
3616
3617                 public override void Emit (EmitContext ec)
3618                 {
3619                         ILGenerator ig = ec.ig;
3620                         Label false_target = ig.DefineLabel ();
3621                         Label end_target = ig.DefineLabel ();
3622
3623                         expr.EmitBranchable (ec, false_target, false);
3624                         trueExpr.Emit (ec);
3625                         ig.Emit (OpCodes.Br, end_target);
3626                         ig.MarkLabel (false_target);
3627                         falseExpr.Emit (ec);
3628                         ig.MarkLabel (end_target);
3629                 }
3630
3631         }
3632
3633         /// <summary>
3634         ///   Local variables
3635         /// </summary>
3636         public class LocalVariableReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
3637                 public readonly string Name;
3638                 public readonly Block Block;
3639                 public LocalInfo local_info;
3640                 bool is_readonly;
3641                 bool prepared;
3642                 LocalTemporary temp;
3643
3644                 public LocalVariableReference (Block block, string name, Location l)
3645                 {
3646                         Block = block;
3647                         Name = name;
3648                         loc = l;
3649                         eclass = ExprClass.Variable;
3650                 }
3651
3652                 //
3653                 // Setting `is_readonly' to false will allow you to create a writable
3654                 // reference to a read-only variable.  This is used by foreach and using.
3655                 //
3656                 public LocalVariableReference (Block block, string name, Location l,
3657                                                LocalInfo local_info, bool is_readonly)
3658                         : this (block, name, l)
3659                 {
3660                         this.local_info = local_info;
3661                         this.is_readonly = is_readonly;
3662                 }
3663
3664                 public VariableInfo VariableInfo {
3665                         get {
3666                                 return local_info.VariableInfo;
3667                         }
3668                 }
3669
3670                 public bool IsReadOnly {
3671                         get {
3672                                 return is_readonly;
3673                         }
3674                 }
3675
3676                 protected Expression DoResolveBase (EmitContext ec, Expression lvalue_right_side)
3677                 {
3678                         if (local_info == null) {
3679                                 local_info = Block.GetLocalInfo (Name);
3680
3681                                 // is out param
3682                                 if (lvalue_right_side == EmptyExpression.Null)
3683                                         local_info.Used = true;
3684
3685                                 is_readonly = local_info.ReadOnly;
3686                         }
3687
3688                         type = local_info.VariableType;
3689
3690                         VariableInfo variable_info = local_info.VariableInfo;
3691                         if (lvalue_right_side != null){
3692                                 if (is_readonly){
3693                                         Error (1604, "cannot assign to `" + Name + "' because it is readonly");
3694                                         return null;
3695                                 }
3696
3697                                 if (variable_info != null)
3698                                         variable_info.SetAssigned (ec);
3699                 }
3700
3701                         Expression e = Block.GetConstantExpression (Name);
3702                         if (e != null) {
3703                                 local_info.Used = true;
3704                                 eclass = ExprClass.Value;
3705                                 return e.Resolve (ec);
3706                         }
3707
3708                         if ((variable_info != null) && !variable_info.IsAssigned (ec, loc))
3709                                 return null;
3710
3711                         if (lvalue_right_side == null)
3712                                 local_info.Used = true;
3713
3714                         if (ec.CurrentAnonymousMethod != null){
3715                                 //
3716                                 // If we are referencing a variable from the external block
3717                                 // flag it for capturing
3718                                 //
3719                                 if (local_info.Block.Toplevel != ec.CurrentBlock.Toplevel){
3720                                         if (local_info.AddressTaken){
3721                                                 AnonymousMethod.Error_AddressOfCapturedVar (local_info.Name, loc);
3722                                                 return null;
3723                                         }
3724                                         ec.CaptureVariable (local_info);
3725                                 }
3726                         }
3727
3728                         return this;
3729                 }
3730
3731                 public override Expression DoResolve (EmitContext ec)
3732                 {
3733                         return DoResolveBase (ec, null);
3734                 }
3735
3736                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
3737                 {
3738                         Expression ret = DoResolveBase (ec, right_side);
3739                         if (ret != null)
3740                                 CheckObsoleteAttribute (ret.Type);
3741
3742                         return ret;
3743                 }
3744
3745                 public bool VerifyFixed (bool is_expression)
3746                 {
3747                         return !is_expression || local_info.IsFixed;
3748                 }
3749
3750                 public override void Emit (EmitContext ec)
3751                 {
3752                         ILGenerator ig = ec.ig;
3753
3754                         if (local_info.FieldBuilder == null){
3755                                 //
3756                                 // A local variable on the local CLR stack
3757                                 //
3758                         ig.Emit (OpCodes.Ldloc, local_info.LocalBuilder);
3759                         } else {
3760                                 //
3761                                 // A local variable captured by anonymous methods.
3762                                 //
3763                                 if (!prepared)
3764                                         ec.EmitCapturedVariableInstance (local_info);
3765
3766                                 ig.Emit (OpCodes.Ldfld, local_info.FieldBuilder);
3767                         }
3768                 }
3769
3770                 public void Emit (EmitContext ec, bool leave_copy)
3771                 {
3772                         Emit (ec);
3773                         if (leave_copy){
3774                                 ec.ig.Emit (OpCodes.Dup);
3775                                 if (local_info.FieldBuilder != null){
3776                                         temp = new LocalTemporary (ec, Type);
3777                                         temp.Store (ec);
3778                                 }
3779                         }
3780                 }
3781
3782                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
3783                 {
3784                         ILGenerator ig = ec.ig;
3785                         prepared = prepare_for_load;
3786
3787                         if (local_info.FieldBuilder == null){
3788                                 //
3789                                 // A local variable on the local CLR stack
3790                                 //
3791                                 if (local_info.LocalBuilder == null)
3792                                         throw new Exception ("This should not happen: both Field and Local are null");
3793
3794                         source.Emit (ec);
3795                         if (leave_copy)
3796                                 ec.ig.Emit (OpCodes.Dup);
3797                                 ig.Emit (OpCodes.Stloc, local_info.LocalBuilder);
3798                         } else {
3799                                 //
3800                                 // A local variable captured by anonymous methods or itereators.
3801                                 //
3802                                 ec.EmitCapturedVariableInstance (local_info);
3803
3804                                 if (prepare_for_load)
3805                                         ig.Emit (OpCodes.Dup);
3806                                 source.Emit (ec);
3807                                 if (leave_copy){
3808                                         ig.Emit (OpCodes.Dup);
3809                                         temp = new LocalTemporary (ec, Type);
3810                                         temp.Store (ec);
3811                                 }
3812                                 ig.Emit (OpCodes.Stfld, local_info.FieldBuilder);
3813                                 if (temp != null)
3814                                         temp.Emit (ec);
3815                         }
3816                 }
3817
3818                 public void AddressOf (EmitContext ec, AddressOp mode)
3819                 {
3820                         ILGenerator ig = ec.ig;
3821
3822                         if (local_info.FieldBuilder == null){
3823                                 //
3824                                 // A local variable on the local CLR stack
3825                                 //
3826                         ig.Emit (OpCodes.Ldloca, local_info.LocalBuilder);
3827                         } else {
3828                                 //
3829                                 // A local variable captured by anonymous methods or iterators
3830                                 //
3831                                 ec.EmitCapturedVariableInstance (local_info);
3832                                 ig.Emit (OpCodes.Ldflda, local_info.FieldBuilder);
3833                         }
3834                 }
3835
3836                 public override string ToString ()
3837                 {
3838                         return String.Format ("{0} ({1}:{2})", GetType (), Name, loc);
3839                 }
3840         }
3841
3842         /// <summary>
3843         ///   This represents a reference to a parameter in the intermediate
3844         ///   representation.
3845         /// </summary>
3846         public class ParameterReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
3847                 Parameters pars;
3848                 String name;
3849                 int idx;
3850                 Block block;
3851                 VariableInfo vi;
3852                 public Parameter.Modifier mod;
3853                 public bool is_ref, is_out, prepared;
3854
3855                 public bool IsOut {
3856                         get {
3857                                 return is_out;
3858                         }
3859                 }
3860
3861                 public bool IsRef {
3862                         get {
3863                                 return is_ref;
3864                         }
3865                 }
3866
3867                 LocalTemporary temp;
3868
3869                 public ParameterReference (Parameters pars, Block block, int idx, string name, Location loc)
3870                 {
3871                         this.pars = pars;
3872                         this.block = block;
3873                         this.idx  = idx;
3874                         this.name = name;
3875                         this.loc = loc;
3876                         eclass = ExprClass.Variable;
3877                 }
3878
3879                 public VariableInfo VariableInfo {
3880                         get { return vi; }
3881                 }
3882
3883                 public bool VerifyFixed (bool is_expression)
3884                 {
3885                         return !is_expression || TypeManager.IsValueType (type);
3886                 }
3887
3888                 public bool IsAssigned (EmitContext ec, Location loc)
3889                 {
3890                         if (!ec.DoFlowAnalysis || !is_out || ec.CurrentBranching.IsAssigned (vi))
3891                                 return true;
3892
3893                         Report.Error (165, loc,
3894                                       "Use of unassigned parameter `" + name + "'");
3895                         return false;
3896                 }
3897
3898                 public bool IsFieldAssigned (EmitContext ec, string field_name, Location loc)
3899                 {
3900                         if (!ec.DoFlowAnalysis || !is_out || ec.CurrentBranching.IsFieldAssigned (vi, field_name))
3901                                 return true;
3902
3903                         Report.Error (170, loc,
3904                                       "Use of possibly unassigned field `" + field_name + "'");
3905                         return false;
3906                 }
3907
3908                 public void SetAssigned (EmitContext ec)
3909                 {
3910                         if (is_out && ec.DoFlowAnalysis)
3911                                 ec.CurrentBranching.SetAssigned (vi);
3912                 }
3913
3914                 public void SetFieldAssigned (EmitContext ec, string field_name)
3915                 {
3916                         if (is_out && ec.DoFlowAnalysis)
3917                                 ec.CurrentBranching.SetFieldAssigned (vi, field_name);
3918                 }
3919
3920                 protected void DoResolveBase (EmitContext ec)
3921                 {
3922                         type = pars.GetParameterInfo (ec, idx, out mod);
3923                         is_ref = (mod & Parameter.Modifier.ISBYREF) != 0;
3924                         is_out = (mod & Parameter.Modifier.OUT) != 0;
3925                         eclass = ExprClass.Variable;
3926
3927                         if (is_out)
3928                                 vi = block.ParameterMap [idx];
3929
3930                         if (ec.CurrentAnonymousMethod != null){
3931                                 if (is_ref){
3932                                         Report.Error (1628, Location,
3933                                                       "Can not reference a ref or out parameter in an anonymous method");
3934                                         return;
3935                                 }
3936
3937                                 //
3938                                 // If we are referencing the parameter from the external block
3939                                 // flag it for capturing
3940                                 //
3941                                 //Console.WriteLine ("Is parameter `{0}' local? {1}", name, block.IsLocalParameter (name));
3942                                 if (!block.IsLocalParameter (name)){
3943                                         ec.CaptureParameter (name, type, idx);
3944                                 }
3945                         }
3946                 }
3947
3948                 //
3949                 // Notice that for ref/out parameters, the type exposed is not the
3950                 // same type exposed externally.
3951                 //
3952                 // for "ref int a":
3953                 //   externally we expose "int&"
3954                 //   here we expose       "int".
3955                 //
3956                 // We record this in "is_ref".  This means that the type system can treat
3957                 // the type as it is expected, but when we generate the code, we generate
3958                 // the alternate kind of code.
3959                 //
3960                 public override Expression DoResolve (EmitContext ec)
3961                 {
3962                         DoResolveBase (ec);
3963
3964                         if (is_out && ec.DoFlowAnalysis && !IsAssigned (ec, loc))
3965                                 return null;
3966
3967                         if (ec.RemapToProxy)
3968                                 return ec.RemapParameter (idx);
3969
3970                         return this;
3971                 }
3972
3973                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
3974                 {
3975                         DoResolveBase (ec);
3976
3977                         SetAssigned (ec);
3978
3979                         if (ec.RemapToProxy)
3980                                 return ec.RemapParameterLValue (idx, right_side);
3981
3982                         return this;
3983                 }
3984
3985                 static public void EmitLdArg (ILGenerator ig, int x)
3986                 {
3987                         if (x <= 255){
3988                                 switch (x){
3989                                 case 0: ig.Emit (OpCodes.Ldarg_0); break;
3990                                 case 1: ig.Emit (OpCodes.Ldarg_1); break;
3991                                 case 2: ig.Emit (OpCodes.Ldarg_2); break;
3992                                 case 3: ig.Emit (OpCodes.Ldarg_3); break;
3993                                 default: ig.Emit (OpCodes.Ldarg_S, (byte) x); break;
3994                                 }
3995                         } else
3996                                 ig.Emit (OpCodes.Ldarg, x);
3997                 }
3998
3999                 //
4000                 // This method is used by parameters that are references, that are
4001                 // being passed as references:  we only want to pass the pointer (that
4002                 // is already stored in the parameter, not the address of the pointer,
4003                 // and not the value of the variable).
4004                 //
4005                 public void EmitLoad (EmitContext ec)
4006                 {
4007                         ILGenerator ig = ec.ig;
4008                         int arg_idx = idx;
4009
4010                         if (!ec.IsStatic)
4011                                 arg_idx++;
4012
4013                         EmitLdArg (ig, arg_idx);
4014
4015                         //
4016                         // FIXME: Review for anonymous methods
4017                         //
4018                 }
4019
4020                 public override void Emit (EmitContext ec)
4021                 {
4022                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4023                                 ec.EmitParameter (name);
4024                                 return;
4025                         }
4026
4027                         Emit (ec, false);
4028                 }
4029
4030                 public void Emit (EmitContext ec, bool leave_copy)
4031                 {
4032                         ILGenerator ig = ec.ig;
4033                         int arg_idx = idx;
4034
4035                         if (!ec.IsStatic)
4036                                 arg_idx++;
4037
4038                         EmitLdArg (ig, arg_idx);
4039
4040                         if (is_ref) {
4041                                 if (prepared)
4042                                         ec.ig.Emit (OpCodes.Dup);
4043
4044                                 //
4045                                 // If we are a reference, we loaded on the stack a pointer
4046                                 // Now lets load the real value
4047                                 //
4048                                 LoadFromPtr (ig, type);
4049                         }
4050
4051                         if (leave_copy) {
4052                                 ec.ig.Emit (OpCodes.Dup);
4053
4054                                 if (is_ref) {
4055                                         temp = new LocalTemporary (ec, type);
4056                                         temp.Store (ec);
4057                                 }
4058                         }
4059                 }
4060
4061                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
4062                 {
4063                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4064                                 ec.EmitAssignParameter (name, source, leave_copy, prepare_for_load);
4065                                 return;
4066                         }
4067
4068                         ILGenerator ig = ec.ig;
4069                         int arg_idx = idx;
4070
4071                         prepared = prepare_for_load;
4072
4073                         if (!ec.IsStatic)
4074                                 arg_idx++;
4075
4076                         if (is_ref && !prepared)
4077                                 EmitLdArg (ig, arg_idx);
4078
4079                         source.Emit (ec);
4080
4081                         if (leave_copy)
4082                                 ec.ig.Emit (OpCodes.Dup);
4083
4084                         if (is_ref) {
4085                                 if (leave_copy) {
4086                                         temp = new LocalTemporary (ec, type);
4087                                         temp.Store (ec);
4088                                 }
4089
4090                                 StoreFromPtr (ig, type);
4091
4092                                 if (temp != null)
4093                                         temp.Emit (ec);
4094                         } else {
4095                                 if (arg_idx <= 255)
4096                                         ig.Emit (OpCodes.Starg_S, (byte) arg_idx);
4097                                 else
4098                                         ig.Emit (OpCodes.Starg, arg_idx);
4099                         }
4100                 }
4101
4102                 public void AddressOf (EmitContext ec, AddressOp mode)
4103                 {
4104                         if (ec.HaveCaptureInfo && ec.IsParameterCaptured (name)){
4105                                 ec.EmitAddressOfParameter (name);
4106                                 return;
4107                         }
4108
4109                         int arg_idx = idx;
4110
4111                         if (!ec.IsStatic)
4112                                 arg_idx++;
4113
4114                         if (is_ref){
4115                                 if (arg_idx <= 255)
4116                                         ec.ig.Emit (OpCodes.Ldarg_S, (byte) arg_idx);
4117                                 else
4118                                         ec.ig.Emit (OpCodes.Ldarg, arg_idx);
4119                         } else {
4120                                 if (arg_idx <= 255)
4121                                         ec.ig.Emit (OpCodes.Ldarga_S, (byte) arg_idx);
4122                                 else
4123                                         ec.ig.Emit (OpCodes.Ldarga, arg_idx);
4124                         }
4125                 }
4126
4127         }
4128
4129         /// <summary>
4130         ///   Used for arguments to New(), Invocation()
4131         /// </summary>
4132         public class Argument {
4133                 public enum AType : byte {
4134                         Expression,
4135                         Ref,
4136                         Out,
4137                         ArgList
4138                 };
4139
4140                 public readonly AType ArgType;
4141                 public Expression Expr;
4142
4143                 public Argument (Expression expr, AType type)
4144                 {
4145                         this.Expr = expr;
4146                         this.ArgType = type;
4147                 }
4148
4149                 public Argument (Expression expr)
4150                 {
4151                         this.Expr = expr;
4152                         this.ArgType = AType.Expression;
4153                 }
4154
4155                 public Type Type {
4156                         get {
4157                                 if (ArgType == AType.Ref || ArgType == AType.Out)
4158                                         return TypeManager.GetReferenceType (Expr.Type);
4159                                 else
4160                                         return Expr.Type;
4161                         }
4162                 }
4163
4164                 public Parameter.Modifier GetParameterModifier ()
4165                 {
4166                         switch (ArgType) {
4167                         case AType.Out:
4168                                 return Parameter.Modifier.OUT | Parameter.Modifier.ISBYREF;
4169
4170                         case AType.Ref:
4171                                 return Parameter.Modifier.REF | Parameter.Modifier.ISBYREF;
4172
4173                         default:
4174                                 return Parameter.Modifier.NONE;
4175                         }
4176                 }
4177
4178                 public static string FullDesc (Argument a)
4179                 {
4180                         if (a.ArgType == AType.ArgList)
4181                                 return "__arglist";
4182
4183                         return (a.ArgType == AType.Ref ? "ref " :
4184                                 (a.ArgType == AType.Out ? "out " : "")) +
4185                                 TypeManager.CSharpName (a.Expr.Type);
4186                 }
4187
4188                 public bool ResolveMethodGroup (EmitContext ec, Location loc)
4189                 {
4190                         ConstructedType ctype = Expr as ConstructedType;
4191                         if (ctype != null)
4192                                 Expr = ctype.GetSimpleName (ec);
4193
4194                         // FIXME: csc doesn't report any error if you try to use `ref' or
4195                         //        `out' in a delegate creation expression.
4196                         Expr = Expr.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
4197                         if (Expr == null)
4198                                 return false;
4199
4200                         return true;
4201                 }
4202
4203                 public bool Resolve (EmitContext ec, Location loc)
4204                 {
4205                         if (ArgType == AType.Ref) {
4206                                 Expr = Expr.Resolve (ec);
4207                                 if (Expr == null)
4208                                         return false;
4209
4210                                 if (!ec.IsConstructor) {
4211                                         FieldExpr fe = Expr as FieldExpr;
4212                                         if (fe != null && fe.FieldInfo.IsInitOnly) {
4213                                                 if (fe.FieldInfo.IsStatic)
4214                                                         Report.Error (199, loc, "A static readonly field cannot be passed ref or out (except in a static constructor)");
4215                                                 else
4216                                                         Report.Error (192, loc, "A readonly field cannot be passed ref or out (except in a constructor)");
4217                                                 return false;
4218                                         }
4219                                 }
4220                                 Expr = Expr.ResolveLValue (ec, Expr);
4221                         } else if (ArgType == AType.Out)
4222                                 Expr = Expr.ResolveLValue (ec, EmptyExpression.Null);
4223                         else
4224                                 Expr = Expr.Resolve (ec);
4225
4226                         if (Expr == null)
4227                                 return false;
4228
4229                         if (ArgType == AType.Expression)
4230                                 return true;
4231                         else {
4232                                 //
4233                                 // Catch errors where fields of a MarshalByRefObject are passed as ref or out
4234                                 // This is only allowed for `this'
4235                                 //
4236                                 FieldExpr fe = Expr as FieldExpr;
4237                                 if (fe != null && !fe.IsStatic){
4238                                         Expression instance = fe.InstanceExpression;
4239
4240                                         if (instance.GetType () != typeof (This)){
4241                                                 if (fe.InstanceExpression.Type.IsSubclassOf (TypeManager.mbr_type)){
4242                                                         Report.SymbolRelatedToPreviousError (fe.InstanceExpression.Type);
4243                                                         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",
4244                                                                 fe.Name);
4245                                                         return false;
4246                                                 }
4247                                         }
4248                                 }
4249                         }
4250
4251                         if (Expr.eclass != ExprClass.Variable){
4252                                 //
4253                                 // We just probe to match the CSC output
4254                                 //
4255                                 if (Expr.eclass == ExprClass.PropertyAccess ||
4256                                     Expr.eclass == ExprClass.IndexerAccess){
4257                                         Report.Error (
4258                                                 206, loc,
4259                                                 "A property or indexer can not be passed as an out or ref " +
4260                                                 "parameter");
4261                                 } else {
4262                                         Report.Error (
4263                                                 1510, loc,
4264                                                 "An lvalue is required as an argument to out or ref");
4265                                 }
4266                                 return false;
4267                         }
4268
4269                         return true;
4270                 }
4271
4272                 public void Emit (EmitContext ec)
4273                 {
4274                         //
4275                         // Ref and Out parameters need to have their addresses taken.
4276                         //
4277                         // ParameterReferences might already be references, so we want
4278                         // to pass just the value
4279                         //
4280                         if (ArgType == AType.Ref || ArgType == AType.Out){
4281                                 AddressOp mode = AddressOp.Store;
4282
4283                                 if (ArgType == AType.Ref)
4284                                         mode |= AddressOp.Load;
4285
4286                                 if (Expr is ParameterReference){
4287                                         ParameterReference pr = (ParameterReference) Expr;
4288
4289                                         if (pr.IsRef)
4290                                                 pr.EmitLoad (ec);
4291                                         else {
4292
4293                                                 pr.AddressOf (ec, mode);
4294                                         }
4295                                 } else {
4296                                         if (Expr is IMemoryLocation)
4297                                                ((IMemoryLocation) Expr).AddressOf (ec, mode);
4298                                         else {
4299                                                 Report.Error (
4300                                                         1510, Expr.Location,
4301                                                         "An lvalue is required as an argument to out or ref");
4302                                                 return;
4303                                         }
4304                                 }
4305                         } else
4306                                 Expr.Emit (ec);
4307                 }
4308         }
4309
4310         /// <summary>
4311         ///   Invocation of methods or delegates.
4312         /// </summary>
4313         public class Invocation : ExpressionStatement {
4314                 public readonly ArrayList Arguments;
4315
4316                 Expression expr;
4317                 MethodBase method = null;
4318
4319                 //
4320                 // arguments is an ArrayList, but we do not want to typecast,
4321                 // as it might be null.
4322                 //
4323                 // FIXME: only allow expr to be a method invocation or a
4324                 // delegate invocation (7.5.5)
4325                 //
4326                 public Invocation (Expression expr, ArrayList arguments, Location l)
4327                 {
4328                         this.expr = expr;
4329                         Arguments = arguments;
4330                         loc = l;
4331                 }
4332
4333                 public Expression Expr {
4334                         get {
4335                                 return expr;
4336                         }
4337                 }
4338
4339                 /// <summary>
4340                 ///   Determines "better conversion" as specified in 7.4.2.3
4341                 ///
4342                 ///    Returns : p    if a->p is better,
4343                 ///              q    if a->q is better,
4344                 ///              null if neither is better
4345                 /// </summary>
4346                 static Type BetterConversion (EmitContext ec, Argument a, Type p, Type q, Location loc)
4347                 {
4348                         Type argument_type = TypeManager.TypeToCoreType (a.Type);
4349                         Expression argument_expr = a.Expr;
4350
4351                         // p = TypeManager.TypeToCoreType (p);
4352                         // q = TypeManager.TypeToCoreType (q);
4353
4354                         if (argument_type == null)
4355                                 throw new Exception ("Expression of type " + a.Expr +
4356                                                      " does not resolve its type");
4357
4358                         if (p == null || q == null)
4359                                 throw new InternalErrorException ("BetterConversion Got a null conversion");
4360
4361                         if (p == q)
4362                                 return null;
4363
4364                         if (argument_expr is NullLiteral) {
4365                         //
4366                                 // If the argument is null and one of the types to compare is 'object' and
4367                                 // the other is a reference type, we prefer the other.
4368                         //
4369                                 // This follows from the usual rules:
4370                                 //   * There is an implicit conversion from 'null' to type 'object'
4371                                 //   * There is an implicit conversion from 'null' to any reference type
4372                                 //   * There is an implicit conversion from any reference type to type 'object'
4373                                 //   * There is no implicit conversion from type 'object' to other reference types
4374                                 //  => Conversion of 'null' to a reference type is better than conversion to 'object'
4375                                 //
4376                                 //  FIXME: This probably isn't necessary, since the type of a NullLiteral is the
4377                                 //         null type. I think it used to be 'object' and thus needed a special
4378                                 //         case to avoid the immediately following two checks.
4379                                 //
4380                                 if (!p.IsValueType && q == TypeManager.object_type)
4381                                         return p;
4382                                 if (!q.IsValueType && p == TypeManager.object_type)
4383                                         return q;
4384                         }
4385
4386                         if (argument_type == p)
4387                                 return p;
4388
4389                         if (argument_type == q)
4390                                 return q;
4391
4392                         Expression p_tmp = new EmptyExpression (p);
4393                         Expression q_tmp = new EmptyExpression (q);
4394
4395                         bool p_to_q = Convert.ImplicitConversionExists (ec, p_tmp, q);
4396                         bool q_to_p = Convert.ImplicitConversionExists (ec, q_tmp, p);
4397
4398                         if (p_to_q && !q_to_p)
4399                                 return p;
4400
4401                         if (q_to_p && !p_to_q)
4402                                 return q;
4403
4404                         if (p == TypeManager.sbyte_type)
4405                                 if (q == TypeManager.byte_type || q == TypeManager.ushort_type ||
4406                                     q == TypeManager.uint32_type || q == TypeManager.uint64_type)
4407                                         return p;
4408                         if (q == TypeManager.sbyte_type)
4409                                 if (p == TypeManager.byte_type || p == TypeManager.ushort_type ||
4410                                     p == TypeManager.uint32_type || p == TypeManager.uint64_type)
4411                                         return q;
4412
4413                         if (p == TypeManager.short_type)
4414                                 if (q == TypeManager.ushort_type || q == TypeManager.uint32_type ||
4415                                     q == TypeManager.uint64_type)
4416                                         return p;
4417
4418                         if (q == TypeManager.short_type)
4419                                 if (p == TypeManager.ushort_type || p == TypeManager.uint32_type ||
4420                                     p == TypeManager.uint64_type)
4421                                         return q;
4422
4423                         if (p == TypeManager.int32_type)
4424                                 if (q == TypeManager.uint32_type || q == TypeManager.uint64_type)
4425                                         return p;
4426
4427                         if (q == TypeManager.int32_type)
4428                                 if (p == TypeManager.uint32_type || p == TypeManager.uint64_type)
4429                                         return q;
4430
4431                         if (p == TypeManager.int64_type)
4432                                 if (q == TypeManager.uint64_type)
4433                                         return p;
4434                         if (q == TypeManager.int64_type)
4435                                 if (p == TypeManager.uint64_type)
4436                                         return q;
4437
4438                         return null;
4439                 }
4440
4441                 /// <summary>
4442                 ///   Determines "Better function" between candidate
4443                 ///   and the current best match
4444                 /// </summary>
4445                 /// <remarks>
4446                 ///    Returns a boolean indicating :
4447                 ///     false if candidate ain't better
4448                 ///     true  if candidate is better than the current best match
4449                 /// </remarks>
4450                 static bool BetterFunction (EmitContext ec, ArrayList args, int argument_count,
4451                                            MethodBase candidate, bool candidate_params,
4452                                            MethodBase best, bool best_params, Location loc)
4453                 {
4454                         ParameterData candidate_pd = TypeManager.GetParameterData (candidate);
4455                         ParameterData best_pd = TypeManager.GetParameterData (best);
4456
4457                         int cand_count = candidate_pd.Count;
4458
4459                         //
4460                         // If there is no best method, than this one
4461                         // is better, however, if we already found a
4462                         // best method, we cant tell. This happens
4463                         // if we have:
4464                         //
4465                         //      interface IFoo {
4466                         //              void DoIt ();
4467                         //      }
4468                         //
4469                         //      interface IBar {
4470                         //              void DoIt ();
4471                         //      }
4472                         //
4473                         //      interface IFooBar : IFoo, IBar {}
4474                         //
4475                         // We cant tell if IFoo.DoIt is better than IBar.DoIt
4476                         //
4477                         // However, we have to consider that
4478                         // Trim (); is better than Trim (params char[] chars);
4479                         //
4480                         if (cand_count == 0 && argument_count == 0)
4481                                 return !candidate_params && best_params;
4482
4483                         if ((candidate_pd.ParameterModifier (cand_count - 1) != Parameter.Modifier.PARAMS) &&
4484                             (candidate_pd.ParameterModifier (cand_count - 1) != Parameter.Modifier.ARGLIST))
4485                                 if (cand_count != argument_count)
4486                                         return false;
4487
4488                         bool better_at_least_one = false;
4489                         bool is_equal = true;
4490
4491                         for (int j = 0; j < argument_count; ++j) {
4492                                 Argument a = (Argument) args [j];
4493
4494                                 Type ct = TypeManager.TypeToCoreType (candidate_pd.ParameterType (j));
4495                                 Type bt = TypeManager.TypeToCoreType (best_pd.ParameterType (j));
4496
4497                                 if (candidate_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
4498                                         if (candidate_params)
4499                                                 ct = TypeManager.GetElementType (ct);
4500
4501                                 if (best_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
4502                                         if (best_params)
4503                                                 bt = TypeManager.GetElementType (bt);
4504
4505                                 if (!ct.Equals (bt))
4506                                         is_equal = false;
4507
4508                                 Type better = BetterConversion (ec, a, ct, bt, loc);
4509                                 // for each argument, the conversion to 'ct' should be no worse than
4510                                 // the conversion to 'bt'.
4511                                 if (better == bt)
4512                                         return false;
4513
4514                                 // for at least one argument, the conversion to 'ct' should be better than
4515                                 // the conversion to 'bt'.
4516                                 if (better == ct)
4517                                         better_at_least_one = true;
4518                         }
4519
4520                         //
4521                         // If a method (in the normal form) with the
4522                         // same signature as the expanded form of the
4523                         // current best params method already exists,
4524                         // the expanded form is not applicable so we
4525                         // force it to select the candidate
4526                         //
4527                         if (!candidate_params && best_params && cand_count == argument_count)
4528                                 return true;
4529
4530                         //
4531                         // If two methods have equal parameter types, but
4532                         // only one of them is generic, the non-generic one wins.
4533                         //
4534                         if (is_equal) {
4535                                 if (TypeManager.IsGenericMethod (best) && !TypeManager.IsGenericMethod (candidate))
4536                                         return true;
4537                                 else if (!TypeManager.IsGenericMethod (best) && TypeManager.IsGenericMethod (candidate))
4538                                         return false;
4539                         }
4540
4541                         return better_at_least_one;
4542                 }
4543
4544                 public static string FullMethodDesc (MethodBase mb)
4545                 {
4546                         string ret_type = "";
4547
4548                         if (mb == null)
4549                                 return "";
4550
4551                         if (mb is MethodInfo)
4552                                 ret_type = TypeManager.CSharpName (((MethodInfo) mb).ReturnType);
4553
4554                         StringBuilder sb = new StringBuilder (ret_type);
4555                         sb.Append (" ");
4556                         sb.Append (mb.ReflectedType.ToString ());
4557                         sb.Append (".");
4558                         sb.Append (mb.Name);
4559
4560                         ParameterData pd = TypeManager.GetParameterData (mb);
4561
4562                         int count = pd.Count;
4563                         sb.Append (" (");
4564
4565                         for (int i = count; i > 0; ) {
4566                                 i--;
4567
4568                                 sb.Append (pd.ParameterDesc (count - i - 1));
4569                                 if (i != 0)
4570                                         sb.Append (", ");
4571                         }
4572
4573                         sb.Append (")");
4574                         return sb.ToString ();
4575                 }
4576
4577                 public static MethodGroupExpr MakeUnionSet (Expression mg1, Expression mg2, Location loc)
4578                 {
4579                         MemberInfo [] miset;
4580                         MethodGroupExpr union;
4581
4582                         if (mg1 == null) {
4583                                 if (mg2 == null)
4584                                         return null;
4585                                 return (MethodGroupExpr) mg2;
4586                         } else {
4587                                 if (mg2 == null)
4588                                         return (MethodGroupExpr) mg1;
4589                         }
4590
4591                         MethodGroupExpr left_set = null, right_set = null;
4592                         int length1 = 0, length2 = 0;
4593
4594                         left_set = (MethodGroupExpr) mg1;
4595                         length1 = left_set.Methods.Length;
4596
4597                         right_set = (MethodGroupExpr) mg2;
4598                         length2 = right_set.Methods.Length;
4599
4600                         ArrayList common = new ArrayList ();
4601
4602                         foreach (MethodBase r in right_set.Methods){
4603                                 if (TypeManager.ArrayContainsMethod (left_set.Methods, r))
4604                                         common.Add (r);
4605                         }
4606
4607                         miset = new MemberInfo [length1 + length2 - common.Count];
4608                         left_set.Methods.CopyTo (miset, 0);
4609
4610                         int k = length1;
4611
4612                         foreach (MethodBase r in right_set.Methods) {
4613                                 if (!common.Contains (r))
4614                                         miset [k++] = r;
4615                         }
4616
4617                         union = new MethodGroupExpr (miset, loc);
4618
4619                         return union;
4620                 }
4621
4622                 static bool IsParamsMethodApplicable (EmitContext ec, MethodGroupExpr me,
4623                                                       ArrayList arguments, int arg_count,
4624                                                       ref MethodBase candidate)
4625                 {
4626                         return IsParamsMethodApplicable (
4627                                 ec, me, arguments, arg_count, false, ref candidate) ||
4628                                 IsParamsMethodApplicable (
4629                                         ec, me, arguments, arg_count, true, ref candidate);
4630
4631
4632                 }
4633
4634                 static bool IsParamsMethodApplicable (EmitContext ec, MethodGroupExpr me,
4635                                                       ArrayList arguments, int arg_count,
4636                                                       bool do_varargs, ref MethodBase candidate)
4637                 {
4638                         if (!me.HasTypeArguments &&
4639                             !TypeManager.InferParamsTypeArguments (ec, arguments, ref candidate))
4640                                 return false;
4641
4642                         return IsParamsMethodApplicable (
4643                                 ec, arguments, arg_count, candidate, do_varargs);
4644                 }
4645
4646                 /// <summary>
4647                 ///   Determines if the candidate method, if a params method, is applicable
4648                 ///   in its expanded form to the given set of arguments
4649                 /// </summary>
4650                 static bool IsParamsMethodApplicable (EmitContext ec, ArrayList arguments,
4651                                                       int arg_count, MethodBase candidate,
4652                                                       bool do_varargs)
4653                 {
4654                         ParameterData pd = TypeManager.GetParameterData (candidate);
4655
4656                         int pd_count = pd.Count;
4657
4658                         if (pd_count == 0)
4659                                 return false;
4660
4661                         int count = pd_count - 1;
4662                         if (do_varargs) {
4663                                 if (pd.ParameterModifier (count) != Parameter.Modifier.ARGLIST)
4664                                         return false;
4665                                 if (pd_count != arg_count)
4666                                         return false;
4667                         } else {
4668                                 if (pd.ParameterModifier (count) != Parameter.Modifier.PARAMS)
4669                                 return false;
4670                         }
4671
4672                         if (count > arg_count)
4673                                 return false;
4674
4675                         if (pd_count == 1 && arg_count == 0)
4676                                 return true;
4677
4678                         //
4679                         // If we have come this far, the case which
4680                         // remains is when the number of parameters is
4681                         // less than or equal to the argument count.
4682                         //
4683                         for (int i = 0; i < count; ++i) {
4684
4685                                 Argument a = (Argument) arguments [i];
4686
4687                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
4688                                         (unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF)));
4689                                 Parameter.Modifier p_mod = pd.ParameterModifier (i) &
4690                                         (unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF)));
4691
4692                                 if (a_mod == p_mod) {
4693
4694                                         if (a_mod == Parameter.Modifier.NONE)
4695                                                 if (!Convert.ImplicitConversionExists (ec,
4696                                                                                        a.Expr,
4697                                                                                        pd.ParameterType (i)))
4698                                                         return false;
4699
4700                                         if ((a_mod & Parameter.Modifier.ISBYREF) != 0) {
4701                                                 Type pt = pd.ParameterType (i);
4702
4703                                                 if (!pt.IsByRef)
4704                                                         pt = TypeManager.GetReferenceType (pt);
4705
4706                                                 if (pt != a.Type)
4707                                                         return false;
4708                                         }
4709                                 } else
4710                                         return false;
4711
4712                         }
4713
4714                         if (do_varargs) {
4715                                 Argument a = (Argument) arguments [count];
4716                                 if (!(a.Expr is Arglist))
4717                                         return false;
4718
4719                                 return true;
4720                         }
4721
4722                         Type element_type = TypeManager.GetElementType (pd.ParameterType (pd_count - 1));
4723
4724                         for (int i = pd_count - 1; i < arg_count; i++) {
4725                                 Argument a = (Argument) arguments [i];
4726
4727                                 if (!Convert.ImplicitConversionExists (ec, a.Expr, element_type))
4728                                         return false;
4729                         }
4730
4731                         return true;
4732                 }
4733
4734                 static bool IsApplicable (EmitContext ec, MethodGroupExpr me,
4735                                           ArrayList arguments, int arg_count,
4736                                           ref MethodBase candidate)
4737                 {
4738                         if (!me.HasTypeArguments &&
4739                             !TypeManager.InferTypeArguments (ec, arguments, ref candidate))
4740                                 return false;
4741
4742                         return IsApplicable (ec, arguments, arg_count, candidate);
4743                 }
4744
4745                 /// <summary>
4746                 ///   Determines if the candidate method is applicable (section 14.4.2.1)
4747                 ///   to the given set of arguments
4748                 /// </summary>
4749                 static bool IsApplicable (EmitContext ec, ArrayList arguments, int arg_count,
4750                                           MethodBase candidate)
4751                 {
4752                         ParameterData pd = TypeManager.GetParameterData (candidate);
4753
4754                         if (arg_count != pd.Count)
4755                                 return false;
4756
4757                         for (int i = arg_count; i > 0; ) {
4758                                 i--;
4759
4760                                 Argument a = (Argument) arguments [i];
4761
4762                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
4763                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
4764                                 Parameter.Modifier p_mod = pd.ParameterModifier (i) &
4765                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
4766
4767
4768                                 if (a_mod == p_mod ||
4769                                     (a_mod == Parameter.Modifier.NONE && p_mod == Parameter.Modifier.PARAMS)) {
4770                                         if (a_mod == Parameter.Modifier.NONE) {
4771                                                 if (!Convert.ImplicitConversionExists (ec,
4772                                                                                        a.Expr,
4773                                                                                        pd.ParameterType (i)))
4774                                                         return false;
4775                                         }
4776
4777                                         if ((a_mod & Parameter.Modifier.ISBYREF) != 0) {
4778                                                 Type pt = pd.ParameterType (i);
4779
4780                                                 if (!pt.IsByRef)
4781                                                         pt = TypeManager.GetReferenceType (pt);
4782
4783                                                 if (pt != a.Type)
4784                                                         return false;
4785                                         }
4786                                 } else
4787                                         return false;
4788                         }
4789
4790                         return true;
4791                 }
4792
4793                 static private bool IsAncestralType (Type first_type, Type second_type)
4794                 {
4795                         return first_type != second_type &&
4796                                 (second_type.IsSubclassOf (first_type) ||
4797                                  TypeManager.ImplementsInterface (second_type, first_type));
4798                 }
4799
4800                 /// <summary>
4801                 ///   Find the Applicable Function Members (7.4.2.1)
4802                 ///
4803                 ///   me: Method Group expression with the members to select.
4804                 ///       it might contain constructors or methods (or anything
4805                 ///       that maps to a method).
4806                 ///
4807                 ///   Arguments: ArrayList containing resolved Argument objects.
4808                 ///
4809                 ///   loc: The location if we want an error to be reported, or a Null
4810                 ///        location for "probing" purposes.
4811                 ///
4812                 ///   Returns: The MethodBase (either a ConstructorInfo or a MethodInfo)
4813                 ///            that is the best match of me on Arguments.
4814                 ///
4815                 /// </summary>
4816                 public static MethodBase OverloadResolve (EmitContext ec, MethodGroupExpr me,
4817                                                           ArrayList Arguments, bool may_fail,
4818                                                           Location loc)
4819                 {
4820                         MethodBase method = null;
4821                         bool method_params = false;
4822                         Type applicable_type = null;
4823                         int arg_count = 0;
4824                         ArrayList candidates = new ArrayList ();
4825
4826                         //
4827                         // Used to keep a map between the candidate
4828                         // and whether it is being considered in its
4829                         // normal or expanded form
4830                         //
4831                         // false is normal form, true is expanded form
4832                         //
4833                         Hashtable candidate_to_form = null;
4834
4835                         if (Arguments != null)
4836                                 arg_count = Arguments.Count;
4837
4838                         if ((me.Name == "Invoke") &&
4839                             TypeManager.IsDelegateType (me.DeclaringType)) {
4840                                 Error_InvokeOnDelegate (loc);
4841                                 return null;
4842                         }
4843
4844                         MethodBase[] methods = me.Methods;
4845
4846                         //
4847                         // First we construct the set of applicable methods
4848                         //
4849                         bool is_sorted = true;
4850                         for (int i = 0; i < methods.Length; i++){
4851                                 Type decl_type = methods [i].DeclaringType;
4852
4853                                 //
4854                                 // If we have already found an applicable method
4855                                 // we eliminate all base types (Section 14.5.5.1)
4856                                 //
4857                                 if ((applicable_type != null) &&
4858                                     IsAncestralType (decl_type, applicable_type))
4859                                         continue;
4860
4861                                 //
4862                                 // Check if candidate is applicable (section 14.4.2.1)
4863                                 //   Is candidate applicable in normal form?
4864                                 //
4865                                 bool is_applicable = IsApplicable (
4866                                         ec, me, Arguments, arg_count, ref methods [i]);
4867
4868                                 if (!is_applicable &&
4869                                     (IsParamsMethodApplicable (
4870                                             ec, me, Arguments, arg_count, ref methods [i]))) {
4871                                         MethodBase candidate = methods [i];
4872                                         if (candidate_to_form == null)
4873                                                 candidate_to_form = new PtrHashtable ();
4874                                         candidate_to_form [candidate] = candidate;
4875                                         // Candidate is applicable in expanded form
4876                                         is_applicable = true;
4877                                 }
4878
4879                                 if (!is_applicable)
4880                                         continue;
4881
4882                                 candidates.Add (methods [i]);
4883
4884                                 if (applicable_type == null)
4885                                         applicable_type = decl_type;
4886                                 else if (applicable_type != decl_type) {
4887                                         is_sorted = false;
4888                                         if (IsAncestralType (applicable_type, decl_type))
4889                                                 applicable_type = decl_type;
4890                                 }
4891                         }
4892
4893                         int candidate_top = candidates.Count;
4894
4895                         if (candidate_top == 0) {
4896                                 //
4897                                 // Okay so we have failed to find anything so we
4898                                 // return by providing info about the closest match
4899                                 //
4900                                 for (int i = 0; i < methods.Length; ++i) {
4901                                         MethodBase c = (MethodBase) methods [i];
4902                                         ParameterData pd = TypeManager.GetParameterData (c);
4903
4904                                         if (pd.Count != arg_count)
4905                                                 continue;
4906
4907                                         if (!TypeManager.InferTypeArguments (ec, Arguments, ref c))
4908                                                 continue;
4909
4910                                         VerifyArgumentsCompat (ec, Arguments, arg_count,
4911                                                                c, false, null, may_fail, loc);
4912                                         break;
4913                                 }
4914
4915                                 if (!may_fail) {
4916                                         string report_name = me.Name;
4917                                         if (report_name == ".ctor")
4918                                                 report_name = me.DeclaringType.ToString ();
4919
4920                                         for (int i = 0; i < methods.Length; ++i) {
4921                                                 MethodBase c = methods [i];
4922                                                 ParameterData pd = TypeManager.GetParameterData (c);
4923
4924                                                 if (pd.Count != arg_count)
4925                                                         continue;
4926
4927                                                 if (TypeManager.InferTypeArguments (ec, Arguments, ref c))
4928                                                         continue;
4929
4930                                                 Report.Error (
4931                                                         411, loc, "The type arguments for " +
4932                                                         "method `{0}' cannot be infered from " +
4933                                                         "the usage. Try specifying the type " +
4934                                                         "arguments explicitly.", report_name);
4935                                                 return null;
4936                                         }
4937
4938                                         Error_WrongNumArguments (
4939                                                 loc, report_name, arg_count);
4940                                         return null;
4941                                 }
4942
4943                                 return null;
4944                         }
4945
4946                         if (!is_sorted) {
4947                                 //
4948                                 // At this point, applicable_type is _one_ of the most derived types
4949                                 // in the set of types containing the methods in this MethodGroup.
4950                                 // Filter the candidates so that they only contain methods from the
4951                                 // most derived types.
4952                                 //
4953
4954                                 int finalized = 0; // Number of finalized candidates
4955
4956                                 do {
4957                                         // Invariant: applicable_type is a most derived type
4958
4959                                         // We'll try to complete Section 14.5.5.1 for 'applicable_type' by
4960                                         // eliminating all it's base types.  At the same time, we'll also move
4961                                         // every unrelated type to the end of the array, and pick the next
4962                                         // 'applicable_type'.
4963
4964                                         Type next_applicable_type = null;
4965                                         int j = finalized; // where to put the next finalized candidate
4966                                         int k = finalized; // where to put the next undiscarded candidate
4967                                         for (int i = finalized; i < candidate_top; ++i) {
4968                                                 Type decl_type = ((MethodBase) candidates[i]).DeclaringType;
4969
4970                                                 if (decl_type == applicable_type) {
4971                                                         candidates[k++] = candidates[j];
4972                                                         candidates[j++] = candidates[i];
4973                                                         continue;
4974                                                 }
4975
4976                                                 if (IsAncestralType (decl_type, applicable_type))
4977                                                         continue;
4978
4979                                                 if (next_applicable_type != null &&
4980                                                     IsAncestralType (decl_type, next_applicable_type))
4981                                                         continue;
4982
4983                                                 candidates[k++] = candidates[i];
4984
4985                                                 if (next_applicable_type == null ||
4986                                                     IsAncestralType (next_applicable_type, decl_type))
4987                                                         next_applicable_type = decl_type;
4988                                         }
4989
4990                                         applicable_type = next_applicable_type;
4991                                         finalized = j;
4992                                         candidate_top = k;
4993                                 } while (applicable_type != null);
4994                         }
4995
4996                         //
4997                         // Now we actually find the best method
4998                         //
4999
5000                         method = (MethodBase) candidates[0];
5001                         method_params = candidate_to_form != null && candidate_to_form.Contains (method);
5002                         for (int ix = 1; ix < candidate_top; ix++){
5003                                 MethodBase candidate = (MethodBase) candidates [ix];
5004                                 bool cand_params = candidate_to_form != null && candidate_to_form.Contains (candidate);
5005
5006                                 if (BetterFunction (ec, Arguments, arg_count,
5007                                                     candidate, cand_params,
5008                                                     method, method_params, loc)) {
5009                                         method = candidate;
5010                                         method_params = cand_params;
5011                                 }
5012                         }
5013
5014                         //
5015                         // Now check that there are no ambiguities i.e the selected method
5016                         // should be better than all the others
5017                         //
5018                         bool ambiguous = false;
5019                         for (int ix = 0; ix < candidate_top; ix++){
5020                                 MethodBase candidate = (MethodBase) candidates [ix];
5021
5022                                 if (candidate == method)
5023                                         continue;
5024
5025                                 bool cand_params = candidate_to_form != null && candidate_to_form.Contains (candidate);
5026                                 if (!BetterFunction (ec, Arguments, arg_count,
5027                                                     method, method_params,
5028                                                     candidate, cand_params,
5029                                                      loc)) {
5030                                         Report.SymbolRelatedToPreviousError (candidate);
5031                                         ambiguous = true;
5032                                 }
5033                         }
5034
5035                         if (ambiguous) {
5036                                 Report.SymbolRelatedToPreviousError (method);
5037                                 Report.Error (121, loc, "Ambiguous call when selecting function due to implicit casts");
5038                                 return null;
5039                         }
5040
5041                         //
5042                         // And now check if the arguments are all
5043                         // compatible, perform conversions if
5044                         // necessary etc. and return if everything is
5045                         // all right
5046                         //
5047                         if (!VerifyArgumentsCompat (ec, Arguments, arg_count, method,
5048                                                     method_params, null, may_fail, loc))
5049                                 return null;
5050
5051                         return method;
5052                 }
5053
5054                 static void Error_WrongNumArguments (Location loc, String name, int arg_count)
5055                 {
5056                         Report.Error (1501, loc,
5057                                       "No overload for method `" + name + "' takes `" +
5058                                       arg_count + "' arguments");
5059                 }
5060
5061                 static void Error_InvokeOnDelegate (Location loc)
5062                 {
5063                         Report.Error (1533, loc,
5064                                       "Invoke cannot be called directly on a delegate");
5065                 }
5066
5067                 static void Error_InvalidArguments (Location loc, int idx, MethodBase method,
5068                                                     Type delegate_type, string arg_sig, string par_desc)
5069                 {
5070                         if (delegate_type == null)
5071                                 Report.Error (1502, loc,
5072                                               "The best overloaded match for method '" +
5073                                               FullMethodDesc (method) +
5074                                               "' has some invalid arguments");
5075                         else
5076                                 Report.Error (1594, loc,
5077                                               "Delegate '" + delegate_type.ToString () +
5078                                               "' has some invalid arguments.");
5079                         Report.Error (1503, loc,
5080                                       String.Format ("Argument {0}: Cannot convert from '{1}' to '{2}'",
5081                                                      idx, arg_sig, par_desc));
5082                 }
5083
5084                 public static bool VerifyArgumentsCompat (EmitContext ec, ArrayList Arguments,
5085                                                           int arg_count, MethodBase method,
5086                                                           bool chose_params_expanded,
5087                                                           Type delegate_type, bool may_fail,
5088                                                           Location loc)
5089                 {
5090                         ParameterData pd = TypeManager.GetParameterData (method);
5091                         int pd_count = pd.Count;
5092
5093                         for (int j = 0; j < arg_count; j++) {
5094                                 Argument a = (Argument) Arguments [j];
5095                                 Expression a_expr = a.Expr;
5096                                 Type parameter_type = pd.ParameterType (j);
5097                                 Parameter.Modifier pm = pd.ParameterModifier (j);
5098
5099                                 if (pm == Parameter.Modifier.PARAMS){
5100                                         if ((pm & ~Parameter.Modifier.PARAMS) != a.GetParameterModifier ()) {
5101                                                 if (!may_fail)
5102                                                         Error_InvalidArguments (
5103                                                                 loc, j, method, delegate_type,
5104                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5105                                                 return false;
5106                                         }
5107
5108                                         if (chose_params_expanded)
5109                                                 parameter_type = TypeManager.GetElementType (parameter_type);
5110                                 } else if (pm == Parameter.Modifier.ARGLIST){
5111                                         continue;
5112                                 } else {
5113                                         //
5114                                         // Check modifiers
5115                                         //
5116                                         if (pd.ParameterModifier (j) != a.GetParameterModifier ()){
5117                                                 if (!may_fail)
5118                                                         Error_InvalidArguments (
5119                                                                 loc, j, method, delegate_type,
5120                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5121                                                 return false;
5122                                         }
5123                                 }
5124
5125                                 //
5126                                 // Check Type
5127                                 //
5128                                 if (!TypeManager.IsEqual (a.Type, parameter_type)){
5129                                         Expression conv;
5130
5131                                         conv = Convert.ImplicitConversion (ec, a_expr, parameter_type, loc);
5132
5133                                         if (conv == null) {
5134                                                 if (!may_fail)
5135                                                         Error_InvalidArguments (
5136                                                                 loc, j, method, delegate_type,
5137                                                                 Argument.FullDesc (a), pd.ParameterDesc (j));
5138                                                 return false;
5139                                         }
5140
5141                                         //
5142                                         // Update the argument with the implicit conversion
5143                                         //
5144                                         if (a_expr != conv)
5145                                                 a.Expr = conv;
5146                                 }
5147
5148                                 if (parameter_type.IsPointer){
5149                                         if (!ec.InUnsafe){
5150                                                 UnsafeError (loc);
5151                                                 return false;
5152                                         }
5153                                 }
5154
5155                                 Parameter.Modifier a_mod = a.GetParameterModifier () &
5156                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
5157                                 Parameter.Modifier p_mod = pd.ParameterModifier (j) &
5158                                         unchecked (~(Parameter.Modifier.OUT | Parameter.Modifier.REF));
5159
5160                                 if (a_mod != p_mod &&
5161                                     pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS) {
5162                                         if (!may_fail) {
5163                                                 Report.Error (1502, loc,
5164                                                        "The best overloaded match for method '" + FullMethodDesc (method)+
5165                                                        "' has some invalid arguments");
5166                                                 Report.Error (1503, loc,
5167                                                        "Argument " + (j+1) +
5168                                                        ": Cannot convert from '" + Argument.FullDesc (a)
5169                                                        + "' to '" + pd.ParameterDesc (j) + "'");
5170                                         }
5171
5172                                         return false;
5173                                 }
5174                         }
5175
5176                         return true;
5177                 }
5178
5179                 public override Expression DoResolve (EmitContext ec)
5180                 {
5181                         //
5182                         // First, resolve the expression that is used to
5183                         // trigger the invocation
5184                         //
5185                         if (expr is ConstructedType)
5186                                 expr = ((ConstructedType) expr).GetSimpleName (ec);
5187
5188                         expr = expr.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
5189                         if (expr == null)
5190                                 return null;
5191
5192                         if (!(expr is MethodGroupExpr)) {
5193                                 Type expr_type = expr.Type;
5194
5195                                 if (expr_type != null){
5196                                         bool IsDelegate = TypeManager.IsDelegateType (expr_type);
5197                                         if (IsDelegate)
5198                                                 return (new DelegateInvocation (
5199                                                         this.expr, Arguments, loc)).Resolve (ec);
5200                                 }
5201                         }
5202
5203                         if (!(expr is MethodGroupExpr)){
5204                                 expr.Error_UnexpectedKind (ResolveFlags.MethodGroup, loc);
5205                                 return null;
5206                         }
5207
5208                         //
5209                         // Next, evaluate all the expressions in the argument list
5210                         //
5211                         if (Arguments != null){
5212                                 foreach (Argument a in Arguments){
5213                                         if (!a.Resolve (ec, loc))
5214                                                 return null;
5215                                 }
5216                         }
5217
5218                         MethodGroupExpr mg = (MethodGroupExpr) expr;
5219                         method = OverloadResolve (ec, mg, Arguments, false, loc);
5220
5221                         if (method == null)
5222                                 return null;
5223
5224                         MethodInfo mi = method as MethodInfo;
5225                         if (mi != null) {
5226                                 type = TypeManager.TypeToCoreType (mi.ReturnType);
5227                                 if (!mi.IsStatic && !mg.IsExplicitImpl && (mg.InstanceExpression == null)) {
5228                                         SimpleName.Error_ObjectRefRequired (ec, loc, mi.Name);
5229                                         return null;
5230                                 }
5231
5232                                 Expression iexpr = mg.InstanceExpression;
5233                                 if (mi.IsStatic && (iexpr != null) && !(iexpr is This)) {
5234                                         if (mg.IdenticalTypeName)
5235                                                 mg.InstanceExpression = null;
5236                                         else {
5237                                                 MemberAccess.error176 (loc, mi.Name);
5238                                                 return null;
5239                                         }
5240                                 }
5241                         }
5242
5243                         if (type.IsPointer){
5244                                 if (!ec.InUnsafe){
5245                                         UnsafeError (loc);
5246                                         return null;
5247                                 }
5248                         }
5249
5250                         //
5251                         // Only base will allow this invocation to happen.
5252                         //
5253                         if (mg.IsBase && method.IsAbstract){
5254                                 Report.Error (205, loc, "Cannot call an abstract base member: " +
5255                                               FullMethodDesc (method));
5256                                 return null;
5257                         }
5258
5259                         if (method.Name == "Finalize" && Arguments == null) {
5260                                 if (mg.IsBase)
5261                                         Report.Error (250, loc, "Do not directly call your base class Finalize method. It is called automatically from your destructor");
5262                                 else
5263                                         Report.Error (245, loc, "Destructors and object.Finalize cannot be called directly. Consider calling IDisposable.Dispose if available");
5264                                 return null;
5265                         }
5266
5267                         if ((method.Attributes & MethodAttributes.SpecialName) != 0){
5268                                 if (TypeManager.LookupDeclSpace (method.DeclaringType) != null || TypeManager.IsSpecialMethod (method)) {
5269                                         Report.Error (571, loc, TypeManager.CSharpSignature (method) + ": can not call operator or accessor");
5270                                         return null;
5271                                 }
5272                         }
5273
5274                         if (mg.InstanceExpression != null)
5275                                 mg.InstanceExpression.CheckMarshallByRefAccess (ec.ContainerType);
5276
5277                         eclass = ExprClass.Value;
5278                         return this;
5279                 }
5280
5281                 // <summary>
5282                 //   Emits the list of arguments as an array
5283                 // </summary>
5284                 static void EmitParams (EmitContext ec, int idx, ArrayList arguments)
5285                 {
5286                         ILGenerator ig = ec.ig;
5287                         int count = arguments.Count - idx;
5288                         Argument a = (Argument) arguments [idx];
5289                         Type t = a.Expr.Type;
5290
5291                         IntConstant.EmitInt (ig, count);
5292                         ig.Emit (OpCodes.Newarr, TypeManager.TypeToCoreType (t));
5293
5294                         int top = arguments.Count;
5295                         for (int j = idx; j < top; j++){
5296                                 a = (Argument) arguments [j];
5297
5298                                 ig.Emit (OpCodes.Dup);
5299                                 IntConstant.EmitInt (ig, j - idx);
5300
5301                                 bool is_stobj, has_type_arg;
5302                                 OpCode op = ArrayAccess.GetStoreOpcode (t, out is_stobj, out has_type_arg);
5303                                 if (is_stobj)
5304                                         ig.Emit (OpCodes.Ldelema, t);
5305
5306                                 a.Emit (ec);
5307
5308                                 if (has_type_arg)
5309                                         ig.Emit (op, t);
5310                                 else
5311                                         ig.Emit (op);
5312                         }
5313                 }
5314
5315                 /// <summary>
5316                 ///   Emits a list of resolved Arguments that are in the arguments
5317                 ///   ArrayList.
5318                 ///
5319                 ///   The MethodBase argument might be null if the
5320                 ///   emission of the arguments is known not to contain
5321                 ///   a `params' field (for example in constructors or other routines
5322                 ///   that keep their arguments in this structure)
5323                 ///
5324                 ///   if `dup_args' is true, a copy of the arguments will be left
5325                 ///   on the stack. If `dup_args' is true, you can specify `this_arg'
5326                 ///   which will be duplicated before any other args. Only EmitCall
5327                 ///   should be using this interface.
5328                 /// </summary>
5329                 public static void EmitArguments (EmitContext ec, MethodBase mb, ArrayList arguments, bool dup_args, LocalTemporary this_arg)
5330                 {
5331                         ParameterData pd;
5332                         if (mb != null)
5333                                 pd = TypeManager.GetParameterData (mb);
5334                         else
5335                                 pd = null;
5336
5337                         LocalTemporary [] temps = null;
5338
5339                         if (dup_args)
5340                                 temps = new LocalTemporary [arguments.Count];
5341
5342                         //
5343                         // If we are calling a params method with no arguments, special case it
5344                         //
5345                         if (arguments == null){
5346                                 if (pd != null && pd.Count > 0 &&
5347                                     pd.ParameterModifier (0) == Parameter.Modifier.PARAMS){
5348                                         ILGenerator ig = ec.ig;
5349
5350                                         IntConstant.EmitInt (ig, 0);
5351                                         ig.Emit (OpCodes.Newarr, TypeManager.GetElementType (pd.ParameterType (0)));
5352                                 }
5353
5354                                 return;
5355                         }
5356
5357                         int top = arguments.Count;
5358
5359                         for (int i = 0; i < top; i++){
5360                                 Argument a = (Argument) arguments [i];
5361
5362                                 if (pd != null){
5363                                         if (pd.ParameterModifier (i) == Parameter.Modifier.PARAMS){
5364                                                 //
5365                                                 // Special case if we are passing the same data as the
5366                                                 // params argument, do not put it in an array.
5367                                                 //
5368                                                 if (pd.ParameterType (i) == a.Type)
5369                                                         a.Emit (ec);
5370                                                 else
5371                                                         EmitParams (ec, i, arguments);
5372                                                 return;
5373                                         }
5374                                 }
5375
5376                                 a.Emit (ec);
5377                                 if (dup_args) {
5378                                         ec.ig.Emit (OpCodes.Dup);
5379                                         (temps [i] = new LocalTemporary (ec, a.Type)).Store (ec);
5380                                 }
5381                         }
5382
5383                         if (dup_args) {
5384                                 if (this_arg != null)
5385                                         this_arg.Emit (ec);
5386
5387                                 for (int i = 0; i < top; i ++)
5388                                         temps [i].Emit (ec);
5389                         }
5390
5391                         if (pd != null && pd.Count > top &&
5392                             pd.ParameterModifier (top) == Parameter.Modifier.PARAMS){
5393                                 ILGenerator ig = ec.ig;
5394
5395                                 IntConstant.EmitInt (ig, 0);
5396                                 ig.Emit (OpCodes.Newarr, TypeManager.GetElementType (pd.ParameterType (top)));
5397                         }
5398                 }
5399
5400                 static Type[] GetVarargsTypes (EmitContext ec, MethodBase mb,
5401                                                ArrayList arguments)
5402                 {
5403                         ParameterData pd = TypeManager.GetParameterData (mb);
5404
5405                         if (arguments == null)
5406                                 return new Type [0];
5407
5408                         Argument a = (Argument) arguments [pd.Count - 1];
5409                         Arglist list = (Arglist) a.Expr;
5410
5411                         return list.ArgumentTypes;
5412                 }
5413
5414                 /// <summary>
5415                 /// This checks the ConditionalAttribute on the method
5416                 /// </summary>
5417                 static bool IsMethodExcluded (MethodBase method, EmitContext ec)
5418                 {
5419                         if (method.IsConstructor)
5420                                 return false;
5421
5422                         IMethodData md = TypeManager.GetMethod (method);
5423                         if (md != null)
5424                                 return md.IsExcluded (ec);
5425
5426                         // For some methods (generated by delegate class) GetMethod returns null
5427                         // because they are not included in builder_to_method table
5428                         if (method.DeclaringType is TypeBuilder)
5429                                 return false;
5430
5431                         return AttributeTester.IsConditionalMethodExcluded (method);
5432                 }
5433
5434                 /// <remarks>
5435                 ///   is_base tells whether we want to force the use of the `call'
5436                 ///   opcode instead of using callvirt.  Call is required to call
5437                 ///   a specific method, while callvirt will always use the most
5438                 ///   recent method in the vtable.
5439                 ///
5440                 ///   is_static tells whether this is an invocation on a static method
5441                 ///
5442                 ///   instance_expr is an expression that represents the instance
5443                 ///   it must be non-null if is_static is false.
5444                 ///
5445                 ///   method is the method to invoke.
5446                 ///
5447                 ///   Arguments is the list of arguments to pass to the method or constructor.
5448                 /// </remarks>
5449                 public static void EmitCall (EmitContext ec, bool is_base,
5450                                              bool is_static, Expression instance_expr,
5451                                              MethodBase method, ArrayList Arguments, Location loc)
5452                 {
5453                         EmitCall (ec, is_base, is_static, instance_expr, method, Arguments, loc, false, false);
5454                 }
5455
5456                 // `dup_args' leaves an extra copy of the arguments on the stack
5457                 // `omit_args' does not leave any arguments at all.
5458                 // So, basically, you could make one call with `dup_args' set to true,
5459                 // and then another with `omit_args' set to true, and the two calls
5460                 // would have the same set of arguments. However, each argument would
5461                 // only have been evaluated once.
5462                 public static void EmitCall (EmitContext ec, bool is_base,
5463                                              bool is_static, Expression instance_expr,
5464                                              MethodBase method, ArrayList Arguments, Location loc,
5465                                              bool dup_args, bool omit_args)
5466                 {
5467                         ILGenerator ig = ec.ig;
5468                         bool struct_call = false;
5469                         bool this_call = false;
5470                         LocalTemporary this_arg = null;
5471
5472                         Type decl_type = method.DeclaringType;
5473
5474                         if (!RootContext.StdLib) {
5475                                 // Replace any calls to the system's System.Array type with calls to
5476                                 // the newly created one.
5477                                 if (method == TypeManager.system_int_array_get_length)
5478                                         method = TypeManager.int_array_get_length;
5479                                 else if (method == TypeManager.system_int_array_get_rank)
5480                                         method = TypeManager.int_array_get_rank;
5481                                 else if (method == TypeManager.system_object_array_clone)
5482                                         method = TypeManager.object_array_clone;
5483                                 else if (method == TypeManager.system_int_array_get_length_int)
5484                                         method = TypeManager.int_array_get_length_int;
5485                                 else if (method == TypeManager.system_int_array_get_lower_bound_int)
5486                                         method = TypeManager.int_array_get_lower_bound_int;
5487                                 else if (method == TypeManager.system_int_array_get_upper_bound_int)
5488                                         method = TypeManager.int_array_get_upper_bound_int;
5489                                 else if (method == TypeManager.system_void_array_copyto_array_int)
5490                                         method = TypeManager.void_array_copyto_array_int;
5491                         }
5492
5493                         if (ec.TestObsoleteMethodUsage) {
5494                                 //
5495                                 // This checks ObsoleteAttribute on the method and on the declaring type
5496                                 //
5497                                 ObsoleteAttribute oa = AttributeTester.GetMethodObsoleteAttribute (method);
5498                                 if (oa != null)
5499                                         AttributeTester.Report_ObsoleteMessage (oa, TypeManager.CSharpSignature (method), loc);
5500
5501                                 oa = AttributeTester.GetObsoleteAttribute (method.DeclaringType);
5502                                 if (oa != null) {
5503                                         AttributeTester.Report_ObsoleteMessage (oa, method.DeclaringType.FullName, loc);
5504                                 }
5505                         }
5506
5507                         if (IsMethodExcluded (method, ec))
5508                                 return;
5509
5510                         if (!is_static){
5511                                 this_call = instance_expr == null;
5512                                 if (decl_type.IsValueType || (!this_call && instance_expr.Type.IsValueType))
5513                                         struct_call = true;
5514
5515                                 //
5516                                 // If this is ourselves, push "this"
5517                                 //
5518                                 if (!omit_args) {
5519                                         Type t = null;
5520                                         if (this_call) {
5521                                                 ig.Emit (OpCodes.Ldarg_0);
5522                                                 t = decl_type;
5523                                         } else {
5524                                                 Type iexpr_type = instance_expr.Type;
5525
5526                                                 //
5527                                                 // Push the instance expression
5528                                                 //
5529                                                 if (TypeManager.IsValueType (iexpr_type)) {
5530                                                         //
5531                                                         // Special case: calls to a function declared in a
5532                                                         // reference-type with a value-type argument need
5533                                                         // to have their value boxed.
5534                                                         if (decl_type.IsValueType ||
5535                                                             iexpr_type.IsGenericParameter) {
5536                                                                 //
5537                                                                 // If the expression implements IMemoryLocation, then
5538                                                                 // we can optimize and use AddressOf on the
5539                                                                 // return.
5540                                                                 //
5541                                                                 // If not we have to use some temporary storage for
5542                                                                 // it.
5543                                                                 if (instance_expr is IMemoryLocation) {
5544                                                                         ((IMemoryLocation)instance_expr).
5545                                                                                 AddressOf (ec, AddressOp.LoadStore);
5546                                                                 } else {
5547                                                                         LocalTemporary temp = new LocalTemporary (ec, iexpr_type);
5548                                                                         instance_expr.Emit (ec);
5549                                                                         temp.Store (ec);
5550                                                                         temp.AddressOf (ec, AddressOp.Load);
5551                                                                 }
5552
5553                                                                 // avoid the overhead of doing this all the time.
5554                                                                 if (dup_args)
5555                                                                         t = TypeManager.GetReferenceType (iexpr_type);
5556                                                         } else {
5557                                                                 instance_expr.Emit (ec);
5558                                                                 ig.Emit (OpCodes.Box, instance_expr.Type);
5559                                                                 t = TypeManager.object_type;
5560                                                         }
5561                                                 } else {
5562                                                         instance_expr.Emit (ec);
5563                                                         t = instance_expr.Type;
5564                                                 }
5565                                         }
5566
5567                                         if (dup_args) {
5568                                                 this_arg = new LocalTemporary (ec, t);
5569                                                 ig.Emit (OpCodes.Dup);
5570                                                 this_arg.Store (ec);
5571                                         }
5572                                 }
5573                         }
5574
5575                         if (!omit_args)
5576                                 EmitArguments (ec, method, Arguments, dup_args, this_arg);
5577
5578                         if ((instance_expr != null) && (instance_expr.Type.IsGenericParameter))
5579                                 ig.Emit (OpCodes.Constrained, instance_expr.Type);
5580
5581                         OpCode call_op;
5582                         if (is_static || struct_call || is_base || (this_call && !method.IsVirtual))
5583                                 call_op = OpCodes.Call;
5584                         else
5585                                 call_op = OpCodes.Callvirt;
5586
5587                         if ((method.CallingConvention & CallingConventions.VarArgs) != 0) {
5588                                 Type[] varargs_types = GetVarargsTypes (ec, method, Arguments);
5589                                 ig.EmitCall (call_op, (MethodInfo) method, varargs_types);
5590                                 return;
5591                         }
5592
5593                         //
5594                         // If you have:
5595                         // this.DoFoo ();
5596                         // and DoFoo is not virtual, you can omit the callvirt,
5597                         // because you don't need the null checking behavior.
5598                         //
5599                         if (method is MethodInfo)
5600                                 ig.Emit (call_op, (MethodInfo) method);
5601                         else
5602                                 ig.Emit (call_op, (ConstructorInfo) method);
5603                 }
5604
5605                 public override void Emit (EmitContext ec)
5606                 {
5607                         MethodGroupExpr mg = (MethodGroupExpr) this.expr;
5608
5609                         EmitCall (ec, mg.IsBase, method.IsStatic, mg.InstanceExpression, method, Arguments, loc);
5610                 }
5611
5612                 public override void EmitStatement (EmitContext ec)
5613                 {
5614                         Emit (ec);
5615
5616                         //
5617                         // Pop the return value if there is one
5618                         //
5619                         if (method is MethodInfo){
5620                                 Type ret = ((MethodInfo)method).ReturnType;
5621                                 if (TypeManager.TypeToCoreType (ret) != TypeManager.void_type)
5622                                         ec.ig.Emit (OpCodes.Pop);
5623                         }
5624                 }
5625         }
5626
5627         public class InvocationOrCast : ExpressionStatement
5628         {
5629                 Expression expr;
5630                 Expression argument;
5631
5632                 public InvocationOrCast (Expression expr, Expression argument, Location loc)
5633                 {
5634                         this.expr = expr;
5635                         this.argument = argument;
5636                         this.loc = loc;
5637                 }
5638
5639                 public override Expression DoResolve (EmitContext ec)
5640                 {
5641                         //
5642                         // First try to resolve it as a cast.
5643                         //
5644                         TypeExpr te = expr.ResolveAsTypeStep (ec) as TypeExpr;
5645                         if ((te != null) && (te.eclass == ExprClass.Type)) {
5646                                 Cast cast = new Cast (te, argument, loc);
5647                                 return cast.Resolve (ec);
5648                         }
5649
5650                         //
5651                         // This can either be a type or a delegate invocation.
5652                         // Let's just resolve it and see what we'll get.
5653                         //
5654                         expr = expr.Resolve (ec, ResolveFlags.Type | ResolveFlags.VariableOrValue);
5655                         if (expr == null)
5656                                 return null;
5657
5658                         //
5659                         // Ok, so it's a Cast.
5660                         //
5661                         if (expr.eclass == ExprClass.Type) {
5662                                 Cast cast = new Cast (new TypeExpression (expr.Type, loc), argument, loc);
5663                                 return cast.Resolve (ec);
5664                         }
5665
5666                         //
5667                         // It's a delegate invocation.
5668                         //
5669                         if (!TypeManager.IsDelegateType (expr.Type)) {
5670                                 Error (149, "Method name expected");
5671                                 return null;
5672                         }
5673
5674                         ArrayList args = new ArrayList ();
5675                         args.Add (new Argument (argument, Argument.AType.Expression));
5676                         DelegateInvocation invocation = new DelegateInvocation (expr, args, loc);
5677                         return invocation.Resolve (ec);
5678                 }
5679
5680                 void error201 ()
5681                 {
5682                         Error (201, "Only assignment, call, increment, decrement and new object " +
5683                                "expressions can be used as a statement");
5684                 }
5685
5686                 public override ExpressionStatement ResolveStatement (EmitContext ec)
5687                 {
5688                         //
5689                         // First try to resolve it as a cast.
5690                         //
5691                         TypeExpr te = expr.ResolveAsTypeStep (ec) as TypeExpr;
5692                         if ((te != null) && (te.eclass == ExprClass.Type)) {
5693                                 error201 ();
5694                                 return null;
5695                         }
5696
5697                         //
5698                         // This can either be a type or a delegate invocation.
5699                         // Let's just resolve it and see what we'll get.
5700                         //
5701                         expr = expr.Resolve (ec, ResolveFlags.Type | ResolveFlags.VariableOrValue);
5702                         if ((expr == null) || (expr.eclass == ExprClass.Type)) {
5703                                 error201 ();
5704                                 return null;
5705                         }
5706
5707                         //
5708                         // It's a delegate invocation.
5709                         //
5710                         if (!TypeManager.IsDelegateType (expr.Type)) {
5711                                 Error (149, "Method name expected");
5712                                 return null;
5713                         }
5714
5715                         ArrayList args = new ArrayList ();
5716                         args.Add (new Argument (argument, Argument.AType.Expression));
5717                         DelegateInvocation invocation = new DelegateInvocation (expr, args, loc);
5718                         return invocation.ResolveStatement (ec);
5719                 }
5720
5721                 public override void Emit (EmitContext ec)
5722                 {
5723                         throw new Exception ("Cannot happen");
5724                 }
5725
5726                 public override void EmitStatement (EmitContext ec)
5727                 {
5728                         throw new Exception ("Cannot happen");
5729                 }
5730         }
5731
5732         //
5733         // This class is used to "disable" the code generation for the
5734         // temporary variable when initializing value types.
5735         //
5736         class EmptyAddressOf : EmptyExpression, IMemoryLocation {
5737                 public void AddressOf (EmitContext ec, AddressOp Mode)
5738                 {
5739                         // nothing
5740                 }
5741         }
5742
5743         /// <summary>
5744         ///    Implements the new expression
5745         /// </summary>
5746         public class New : ExpressionStatement, IMemoryLocation {
5747                 public readonly ArrayList Arguments;
5748
5749                 //
5750                 // During bootstrap, it contains the RequestedType,
5751                 // but if `type' is not null, it *might* contain a NewDelegate
5752                 // (because of field multi-initialization)
5753                 //
5754                 public Expression RequestedType;
5755
5756                 MethodBase method = null;
5757
5758                 //
5759                 // If set, the new expression is for a value_target, and
5760                 // we will not leave anything on the stack.
5761                 //
5762                 Expression value_target;
5763                 bool value_target_set = false;
5764                 bool is_type_parameter = false;
5765
5766                 public New (Expression requested_type, ArrayList arguments, Location l)
5767                 {
5768                         RequestedType = requested_type;
5769                         Arguments = arguments;
5770                         loc = l;
5771                 }
5772
5773                 public bool SetValueTypeVariable (Expression value)
5774                 {
5775                         value_target = value;
5776                         value_target_set = true;
5777                         if (!(value_target is IMemoryLocation)){
5778                                 Error_UnexpectedKind ("variable", loc);
5779                                 return false;
5780                         }
5781                         return true;
5782                 }
5783
5784                 //
5785                 // This function is used to disable the following code sequence for
5786                 // value type initialization:
5787                 //
5788                 // AddressOf (temporary)
5789                 // Construct/Init
5790                 // LoadTemporary
5791                 //
5792                 // Instead the provide will have provided us with the address on the
5793                 // stack to store the results.
5794                 //
5795                 static Expression MyEmptyExpression;
5796
5797                 public void DisableTemporaryValueType ()
5798                 {
5799                         if (MyEmptyExpression == null)
5800                                 MyEmptyExpression = new EmptyAddressOf ();
5801
5802                         //
5803                         // To enable this, look into:
5804                         // test-34 and test-89 and self bootstrapping.
5805                         //
5806                         // For instance, we can avoid a copy by using `newobj'
5807                         // instead of Call + Push-temp on value types.
5808 //                      value_target = MyEmptyExpression;
5809                 }
5810
5811                 public override Expression DoResolve (EmitContext ec)
5812                 {
5813                         //
5814                         // The New DoResolve might be called twice when initializing field
5815                         // expressions (see EmitFieldInitializers, the call to
5816                         // GetInitializerExpression will perform a resolve on the expression,
5817                         // and later the assign will trigger another resolution
5818                         //
5819                         // This leads to bugs (#37014)
5820                         //
5821                         if (type != null){
5822                                 if (RequestedType is NewDelegate)
5823                                         return RequestedType;
5824                                 return this;
5825                         }
5826
5827                         TypeExpr texpr = RequestedType.ResolveAsTypeTerminal (ec);
5828                         if (texpr == null)
5829                                 return null;
5830
5831                         type = texpr.Type;
5832                         if (type == null)
5833                                 return null;
5834
5835                         CheckObsoleteAttribute (type);
5836
5837                         bool IsDelegate = TypeManager.IsDelegateType (type);
5838
5839                         if (IsDelegate){
5840                                 RequestedType = (new NewDelegate (type, Arguments, loc)).Resolve (ec);
5841                                 if (RequestedType != null)
5842                                         if (!(RequestedType is DelegateCreation))
5843                                                 throw new Exception ("NewDelegate.Resolve returned a non NewDelegate: " + RequestedType.GetType ());
5844                                 return RequestedType;
5845                         }
5846
5847                         if (type.IsGenericParameter) {
5848                                 if (!TypeManager.HasConstructorConstraint (type)) {
5849                                         Error (304, String.Format (
5850                                                        "Cannot create an instance of the " +
5851                                                        "variable type '{0}' because it " +
5852                                                        "doesn't have the new() constraint",
5853                                                        type));
5854                                         return null;
5855                                 }
5856
5857                                 if ((Arguments != null) && (Arguments.Count != 0)) {
5858                                         Error (417, String.Format (
5859                                                        "`{0}': cannot provide arguments " +
5860                                                        "when creating an instance of a " +
5861                                                        "variable type.", type));
5862                                         return null;
5863                                 }
5864
5865                                 is_type_parameter = true;
5866                                 eclass = ExprClass.Value;
5867                                 return this;
5868                         }
5869
5870                         if (type.IsInterface || type.IsAbstract){
5871                                 Error (144, "It is not possible to create instances of interfaces or abstract classes");
5872                                 return null;
5873                         }
5874
5875                         if (type.IsAbstract && type.IsSealed) {
5876                                 Report.Error (712, loc, "Cannot create an instance of the static class '{0}'", TypeManager.CSharpName (type));
5877                                 return null;
5878                         }
5879
5880                         bool is_struct = type.IsValueType;
5881                         eclass = ExprClass.Value;
5882
5883                         //
5884                         // SRE returns a match for .ctor () on structs (the object constructor),
5885                         // so we have to manually ignore it.
5886                         //
5887                         if (is_struct && Arguments == null)
5888                                 return this;
5889
5890                         Expression ml;
5891                         ml = MemberLookupFinal (ec, type, type, ".ctor",
5892                                                 // For member-lookup, treat 'new Foo (bar)' as call to 'foo.ctor (bar)', where 'foo' is of type 'Foo'.
5893                                                 MemberTypes.Constructor,
5894                                                 AllBindingFlags | BindingFlags.DeclaredOnly, loc);
5895
5896                         if (ml == null)
5897                                 return null;
5898
5899                         if (! (ml is MethodGroupExpr)){
5900                                 if (!is_struct){
5901                                         ml.Error_UnexpectedKind ("method group", loc);
5902                                         return null;
5903                                 }
5904                         }
5905
5906                         if (ml != null) {
5907                                 if (Arguments != null){
5908                                         foreach (Argument a in Arguments){
5909                                                 if (!a.Resolve (ec, loc))
5910                                                         return null;
5911                                         }
5912                                 }
5913
5914                                 method = Invocation.OverloadResolve (
5915                                         ec, (MethodGroupExpr) ml, Arguments, true, loc);
5916
5917                         }
5918
5919                         if (method == null) {
5920                                 if (almostMatchedMembers.Count != 0) {
5921                                         MemberLookupFailed (ec, type, type, ".ctor", null, loc);
5922                                         return null;
5923                                 }
5924
5925                                 if (!is_struct || Arguments.Count > 0) {
5926                                         Error (1501, String.Format (
5927                                             "New invocation: Can not find a constructor in `{0}' for this argument list",
5928                                             TypeManager.CSharpName (type)));
5929                                         return null;
5930                                 }
5931                         }
5932
5933                         return this;
5934                 }
5935
5936                 bool DoEmitTypeParameter (EmitContext ec)
5937                 {
5938                         ILGenerator ig = ec.ig;
5939
5940                         ig.Emit (OpCodes.Ldtoken, type);
5941                         ig.Emit (OpCodes.Call, TypeManager.system_type_get_type_from_handle);
5942                         ig.Emit (OpCodes.Call, TypeManager.activator_create_instance);
5943                         ig.Emit (OpCodes.Unbox_Any, type);
5944
5945                         return true;
5946                 }
5947
5948                 //
5949                 // This DoEmit can be invoked in two contexts:
5950                 //    * As a mechanism that will leave a value on the stack (new object)
5951                 //    * As one that wont (init struct)
5952                 //
5953                 // You can control whether a value is required on the stack by passing
5954                 // need_value_on_stack.  The code *might* leave a value on the stack
5955                 // so it must be popped manually
5956                 //
5957                 // If we are dealing with a ValueType, we have a few
5958                 // situations to deal with:
5959                 //
5960                 //    * The target is a ValueType, and we have been provided
5961                 //      the instance (this is easy, we are being assigned).
5962                 //
5963                 //    * The target of New is being passed as an argument,
5964                 //      to a boxing operation or a function that takes a
5965                 //      ValueType.
5966                 //
5967                 //      In this case, we need to create a temporary variable
5968                 //      that is the argument of New.
5969                 //
5970                 // Returns whether a value is left on the stack
5971                 //
5972                 bool DoEmit (EmitContext ec, bool need_value_on_stack)
5973                 {
5974                         bool is_value_type = TypeManager.IsValueType (type);
5975                         ILGenerator ig = ec.ig;
5976
5977                         if (is_value_type){
5978                                 IMemoryLocation ml;
5979
5980                                 // Allow DoEmit() to be called multiple times.
5981                                 // We need to create a new LocalTemporary each time since
5982                                 // you can't share LocalBuilders among ILGeneators.
5983                                 if (!value_target_set)
5984                                         value_target = new LocalTemporary (ec, type);
5985
5986                                 ml = (IMemoryLocation) value_target;
5987                                 ml.AddressOf (ec, AddressOp.Store);
5988                         }
5989
5990                         if (method != null)
5991                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
5992
5993                         if (is_value_type){
5994                                 if (method == null)
5995                                         ig.Emit (OpCodes.Initobj, type);
5996                                 else
5997                                         ig.Emit (OpCodes.Call, (ConstructorInfo) method);
5998                                 if (need_value_on_stack){
5999                                         value_target.Emit (ec);
6000                                         return true;
6001                                 }
6002                                 return false;
6003                         } else {
6004                                 ig.Emit (OpCodes.Newobj, (ConstructorInfo) method);
6005                                 return true;
6006                         }
6007                 }
6008
6009                 public override void Emit (EmitContext ec)
6010                 {
6011                         if (is_type_parameter)
6012                                 DoEmitTypeParameter (ec);
6013                         else
6014                                 DoEmit (ec, true);
6015                 }
6016
6017                 public override void EmitStatement (EmitContext ec)
6018                 {
6019                         if (is_type_parameter)
6020                                 throw new InvalidOperationException ();
6021
6022                         if (DoEmit (ec, false))
6023                                 ec.ig.Emit (OpCodes.Pop);
6024                 }
6025
6026                 public void AddressOf (EmitContext ec, AddressOp Mode)
6027                 {
6028                         if (is_type_parameter)
6029                                 throw new InvalidOperationException ();
6030
6031                         if (!type.IsValueType){
6032                                 //
6033                                 // We throw an exception.  So far, I believe we only need to support
6034                                 // value types:
6035                                 // foreach (int j in new StructType ())
6036                                 // see bug 42390
6037                                 //
6038                                 throw new Exception ("AddressOf should not be used for classes");
6039                         }
6040
6041                         if (!value_target_set)
6042                                 value_target = new LocalTemporary (ec, type);
6043
6044                         IMemoryLocation ml = (IMemoryLocation) value_target;
6045                         ml.AddressOf (ec, AddressOp.Store);
6046                         if (method != null)
6047                                 Invocation.EmitArguments (ec, method, Arguments, false, null);
6048
6049                         if (method == null)
6050                                 ec.ig.Emit (OpCodes.Initobj, type);
6051                         else
6052                                 ec.ig.Emit (OpCodes.Call, (ConstructorInfo) method);
6053
6054                         ((IMemoryLocation) value_target).AddressOf (ec, Mode);
6055                 }
6056         }
6057
6058         /// <summary>
6059         ///   14.5.10.2: Represents an array creation expression.
6060         /// </summary>
6061         ///
6062         /// <remarks>
6063         ///   There are two possible scenarios here: one is an array creation
6064         ///   expression that specifies the dimensions and optionally the
6065         ///   initialization data and the other which does not need dimensions
6066         ///   specified but where initialization data is mandatory.
6067         /// </remarks>
6068         public class ArrayCreation : Expression {
6069                 Expression requested_base_type;
6070                 ArrayList initializers;
6071
6072                 //
6073                 // The list of Argument types.
6074                 // This is used to construct the `newarray' or constructor signature
6075                 //
6076                 ArrayList arguments;
6077
6078                 //
6079                 // Method used to create the array object.
6080                 //
6081                 MethodBase new_method = null;
6082
6083                 Type array_element_type;
6084                 Type underlying_type;
6085                 bool is_one_dimensional = false;
6086                 bool is_builtin_type = false;
6087                 bool expect_initializers = false;
6088                 int num_arguments = 0;
6089                 int dimensions = 0;
6090                 string rank;
6091
6092                 ArrayList array_data;
6093
6094                 Hashtable bounds;
6095
6096                 //
6097                 // The number of array initializers that we can handle
6098                 // via the InitializeArray method - through EmitStaticInitializers
6099                 //
6100                 int num_automatic_initializers;
6101
6102                 const int max_automatic_initializers = 6;
6103
6104                 public ArrayCreation (Expression requested_base_type, ArrayList exprs, string rank, ArrayList initializers, Location l)
6105                 {
6106                         this.requested_base_type = requested_base_type;
6107                         this.initializers = initializers;
6108                         this.rank = rank;
6109                         loc = l;
6110
6111                         arguments = new ArrayList ();
6112
6113                         foreach (Expression e in exprs) {
6114                                 arguments.Add (new Argument (e, Argument.AType.Expression));
6115                                 num_arguments++;
6116                         }
6117                 }
6118
6119                 public ArrayCreation (Expression requested_base_type, string rank, ArrayList initializers, Location l)
6120                 {
6121                         this.requested_base_type = requested_base_type;
6122                         this.initializers = initializers;
6123                         this.rank = rank;
6124                         loc = l;
6125
6126                         //this.rank = rank.Substring (0, rank.LastIndexOf ('['));
6127                         //
6128                         //string tmp = rank.Substring (rank.LastIndexOf ('['));
6129                         //
6130                         //dimensions = tmp.Length - 1;
6131                         expect_initializers = true;
6132                 }
6133
6134                 public Expression FormArrayType (Expression base_type, int idx_count, string rank)
6135                 {
6136                         StringBuilder sb = new StringBuilder (rank);
6137
6138                         sb.Append ("[");
6139                         for (int i = 1; i < idx_count; i++)
6140                                 sb.Append (",");
6141
6142                         sb.Append ("]");
6143
6144                         return new ComposedCast (base_type, sb.ToString (), loc);
6145                 }
6146
6147                 void Error_IncorrectArrayInitializer ()
6148                 {
6149                         Error (178, "Incorrectly structured array initializer");
6150                 }
6151
6152                 public bool CheckIndices (EmitContext ec, ArrayList probe, int idx, bool specified_dims)
6153                 {
6154                         if (specified_dims) {
6155                                 Argument a = (Argument) arguments [idx];
6156
6157                                 if (!a.Resolve (ec, loc))
6158                                         return false;
6159
6160                                 if (!(a.Expr is Constant)) {
6161                                         Error (150, "A constant value is expected");
6162                                         return false;
6163                                 }
6164
6165                                 int value = (int) ((Constant) a.Expr).GetValue ();
6166
6167                                 if (value != probe.Count) {
6168                                         Error_IncorrectArrayInitializer ();
6169                                         return false;
6170                                 }
6171
6172                                 bounds [idx] = value;
6173                         }
6174
6175                         int child_bounds = -1;
6176                         foreach (object o in probe) {
6177                                 if (o is ArrayList) {
6178                                         int current_bounds = ((ArrayList) o).Count;
6179
6180                                         if (child_bounds == -1)
6181                                                 child_bounds = current_bounds;
6182
6183                                         else if (child_bounds != current_bounds){
6184                                                 Error_IncorrectArrayInitializer ();
6185                                                 return false;
6186                                         }
6187                                         if (specified_dims && (idx + 1 >= arguments.Count)){
6188                                                 Error (623, "Array initializers can only be used in a variable or field initializer, try using the new expression");
6189                                                 return false;
6190                                         }
6191
6192                                         bool ret = CheckIndices (ec, (ArrayList) o, idx + 1, specified_dims);
6193                                         if (!ret)
6194                                                 return false;
6195                                 } else {
6196                                         if (child_bounds != -1){
6197                                                 Error_IncorrectArrayInitializer ();
6198                                                 return false;
6199                                         }
6200
6201                                         Expression tmp = (Expression) o;
6202                                         tmp = tmp.Resolve (ec);
6203                                         if (tmp == null)
6204                                                 return false;
6205
6206                                         // Console.WriteLine ("I got: " + tmp);
6207                                         // Handle initialization from vars, fields etc.
6208
6209                                         Expression conv = Convert.ImplicitConversionRequired (
6210                                                 ec, tmp, underlying_type, loc);
6211
6212                                         if (conv == null)
6213                                                 return false;
6214
6215                                         if (conv is StringConstant || conv is DecimalConstant || conv is NullCast) {
6216                                                 // These are subclasses of Constant that can appear as elements of an
6217                                                 // array that cannot be statically initialized (with num_automatic_initializers
6218                                                 // > max_automatic_initializers), so num_automatic_initializers should be left as zero.
6219                                                 array_data.Add (conv);
6220                                         } else if (conv is Constant) {
6221                                                 // These are the types of Constant that can appear in arrays that can be
6222                                                 // statically allocated.
6223                                                 array_data.Add (conv);
6224                                                 num_automatic_initializers++;
6225                                         } else
6226                                                 array_data.Add (conv);
6227                                 }
6228                         }
6229
6230                         return true;
6231                 }
6232
6233                 public void UpdateIndices (EmitContext ec)
6234                 {
6235                         int i = 0;
6236                         for (ArrayList probe = initializers; probe != null;) {
6237                                 if (probe.Count > 0 && probe [0] is ArrayList) {
6238                                         Expression e = new IntConstant (probe.Count);
6239                                         arguments.Add (new Argument (e, Argument.AType.Expression));
6240
6241                                         bounds [i++] =  probe.Count;
6242
6243                                         probe = (ArrayList) probe [0];
6244
6245                                 } else {
6246                                         Expression e = new IntConstant (probe.Count);
6247                                         arguments.Add (new Argument (e, Argument.AType.Expression));
6248
6249                                         bounds [i++] = probe.Count;
6250                                         probe = null;
6251                                 }
6252                         }
6253
6254                 }
6255
6256                 public bool ValidateInitializers (EmitContext ec, Type array_type)
6257                 {
6258                         if (initializers == null) {
6259                                 if (expect_initializers)
6260                                         return false;
6261                                 else
6262                                         return true;
6263                         }
6264
6265                         if (underlying_type == null)
6266                                 return false;
6267
6268                         //
6269                         // We use this to store all the date values in the order in which we
6270                         // will need to store them in the byte blob later
6271                         //
6272                         array_data = new ArrayList ();
6273                         bounds = new Hashtable ();
6274
6275                         bool ret;
6276
6277                         if (arguments != null) {
6278                                 ret = CheckIndices (ec, initializers, 0, true);
6279                                 return ret;
6280                         } else {
6281                                 arguments = new ArrayList ();
6282
6283                                 ret = CheckIndices (ec, initializers, 0, false);
6284
6285                                 if (!ret)
6286                                         return false;
6287
6288                                 UpdateIndices (ec);
6289
6290                                 if (arguments.Count != dimensions) {
6291                                         Error_IncorrectArrayInitializer ();
6292                                         return false;
6293                                 }
6294
6295                                 return ret;
6296                         }
6297                 }
6298
6299                 //
6300                 // Converts `source' to an int, uint, long or ulong.
6301                 //
6302                 Expression ExpressionToArrayArgument (EmitContext ec, Expression source)
6303                 {
6304                         Expression target;
6305
6306                         bool old_checked = ec.CheckState;
6307                         ec.CheckState = true;
6308
6309                         target = Convert.ImplicitConversion (ec, source, TypeManager.int32_type, loc);
6310                         if (target == null){
6311                                 target = Convert.ImplicitConversion (ec, source, TypeManager.uint32_type, loc);
6312                                 if (target == null){
6313                                         target = Convert.ImplicitConversion (ec, source, TypeManager.int64_type, loc);
6314                                         if (target == null){
6315                                                 target = Convert.ImplicitConversion (ec, source, TypeManager.uint64_type, loc);
6316                                                 if (target == null)
6317                                                         Convert.Error_CannotImplicitConversion (loc, source.Type, TypeManager.int32_type);
6318                                         }
6319                                 }
6320                         }
6321                         ec.CheckState = old_checked;
6322
6323                         //
6324                         // Only positive constants are allowed at compile time
6325                         //
6326                         if (target is Constant){
6327                                 if (target is IntConstant){
6328                                         if (((IntConstant) target).Value < 0){
6329                                                 Expression.Error_NegativeArrayIndex (loc);
6330                                                 return null;
6331                                         }
6332                                 }
6333
6334                                 if (target is LongConstant){
6335                                         if (((LongConstant) target).Value < 0){
6336                                                 Expression.Error_NegativeArrayIndex (loc);
6337                                                 return null;
6338                                         }
6339                                 }
6340
6341                         }
6342
6343                         return target;
6344                 }
6345
6346                 //
6347                 // Creates the type of the array
6348                 //
6349                 bool LookupType (EmitContext ec)
6350                 {
6351                         StringBuilder array_qualifier = new StringBuilder (rank);
6352
6353                         //
6354                         // `In the first form allocates an array instace of the type that results
6355                         // from deleting each of the individual expression from the expression list'
6356                         //
6357                         if (num_arguments > 0) {
6358                                 array_qualifier.Append ("[");
6359                                 for (int i = num_arguments-1; i > 0; i--)
6360                                         array_qualifier.Append (",");
6361                                 array_qualifier.Append ("]");
6362                         }
6363
6364                         //
6365                         // Lookup the type
6366                         //
6367                         TypeExpr array_type_expr;
6368                         array_type_expr = new ComposedCast (requested_base_type, array_qualifier.ToString (), loc);
6369                         array_type_expr = array_type_expr.ResolveAsTypeTerminal (ec);
6370                         if (array_type_expr == null)
6371                                 return false;
6372
6373                         type = array_type_expr.Type;
6374
6375                         if (!type.IsArray) {
6376                                 Error (622, "Can only use array initializer expressions to assign to array types. Try using a new expression instead.");
6377                                 return false;
6378                         }
6379                         underlying_type = TypeManager.GetElementType (type);
6380                         dimensions = type.GetArrayRank ();
6381
6382                         return true;
6383                 }
6384
6385                 public override Expression DoResolve (EmitContext ec)
6386                 {
6387                         int arg_count;
6388
6389                         if (!LookupType (ec))
6390                                 return null;
6391
6392                         //
6393                         // First step is to validate the initializers and fill
6394                         // in any missing bits
6395                         //
6396                         if (!ValidateInitializers (ec, type))
6397                                 return null;
6398
6399                         if (arguments == null)
6400                                 arg_count = 0;
6401                         else {
6402                                 arg_count = arguments.Count;
6403                                 foreach (Argument a in arguments){
6404                                         if (!a.Resolve (ec, loc))
6405                                                 return null;
6406
6407                                         Expression real_arg = ExpressionToArrayArgument (ec, a.Expr, loc);
6408                                         if (real_arg == null)
6409                                                 return null;
6410
6411                                         a.Expr = real_arg;
6412                                 }
6413                         }
6414
6415                         array_element_type = TypeManager.GetElementType (type);
6416
6417                         if (array_element_type.IsAbstract && array_element_type.IsSealed) {
6418                                 Report.Error (719, loc, "'{0}': array elements cannot be of static type", TypeManager.CSharpName (array_element_type));
6419                                 return null;
6420                         }
6421
6422                         if (arg_count == 1) {
6423                                 is_one_dimensional = true;
6424                                 eclass = ExprClass.Value;
6425                                 return this;
6426                         }
6427
6428                         is_builtin_type = TypeManager.IsBuiltinType (type);
6429
6430                         if (is_builtin_type) {
6431                                 Expression ml;
6432
6433                                 ml = MemberLookup (ec, type, ".ctor", MemberTypes.Constructor,
6434                                                    AllBindingFlags, loc);
6435
6436                                 if (!(ml is MethodGroupExpr)) {
6437                                         ml.Error_UnexpectedKind ("method group", loc);
6438                                         return null;
6439                                 }
6440
6441                                 if (ml == null) {
6442                                         Error (-6, "New invocation: Can not find a constructor for " +
6443                                                       "this argument list");
6444                                         return null;
6445                                 }
6446
6447                                 new_method = Invocation.OverloadResolve (
6448                                         ec, (MethodGroupExpr) ml, arguments, false, loc);
6449
6450                                 if (new_method == null) {
6451                                         Error (-6, "New invocation: Can not find a constructor for " +
6452                                                       "this argument list");
6453                                         return null;
6454                                 }
6455
6456                                 eclass = ExprClass.Value;
6457                                 return this;
6458                         } else {
6459                                 ModuleBuilder mb = CodeGen.Module.Builder;
6460                                 ArrayList args = new ArrayList ();
6461
6462                                 if (arguments != null) {
6463                                         for (int i = 0; i < arg_count; i++)
6464                                                 args.Add (TypeManager.int32_type);
6465                                 }
6466
6467                                 Type [] arg_types = null;
6468
6469                                 if (args.Count > 0)
6470                                         arg_types = new Type [args.Count];
6471
6472                                 args.CopyTo (arg_types, 0);
6473
6474                                 new_method = mb.GetArrayMethod (type, ".ctor", CallingConventions.HasThis, null,
6475                                                             arg_types);
6476
6477                                 if (new_method == null) {
6478                                         Error (-6, "New invocation: Can not find a constructor for " +
6479                                                       "this argument list");
6480                                         return null;
6481                                 }
6482
6483                                 eclass = ExprClass.Value;
6484                                 return this;
6485                         }
6486                 }
6487
6488                 public static byte [] MakeByteBlob (ArrayList array_data, Type underlying_type, Location loc)
6489                 {
6490                         int factor;
6491                         byte [] data;
6492                         byte [] element;
6493                         int count = array_data.Count;
6494
6495                         if (underlying_type.IsEnum)
6496                                 underlying_type = TypeManager.EnumToUnderlying (underlying_type);
6497
6498                         factor = GetTypeSize (underlying_type);
6499                         if (factor == 0)
6500                                 throw new Exception ("unrecognized type in MakeByteBlob: " + underlying_type);
6501
6502                         data = new byte [(count * factor + 4) & ~3];
6503                         int idx = 0;
6504
6505                         for (int i = 0; i < count; ++i) {
6506                                 object v = array_data [i];
6507
6508                                 if (v is EnumConstant)
6509                                         v = ((EnumConstant) v).Child;
6510
6511                                 if (v is Constant && !(v is StringConstant))
6512                                         v = ((Constant) v).GetValue ();
6513                                 else {
6514                                         idx += factor;
6515                                         continue;
6516                                 }
6517
6518                                 if (underlying_type == TypeManager.int64_type){
6519                                         if (!(v is Expression)){
6520                                                 long val = (long) v;
6521
6522                                                 for (int j = 0; j < factor; ++j) {
6523                                                         data [idx + j] = (byte) (val & 0xFF);
6524                                                         val = (val >> 8);
6525                                                 }
6526                                         }
6527                                 } else if (underlying_type == TypeManager.uint64_type){
6528                                         if (!(v is Expression)){
6529                                                 ulong val = (ulong) v;
6530
6531                                                 for (int j = 0; j < factor; ++j) {
6532                                                         data [idx + j] = (byte) (val & 0xFF);
6533                                                         val = (val >> 8);
6534                                                 }
6535                                         }
6536                                 } else if (underlying_type == TypeManager.float_type) {
6537                                         if (!(v is Expression)){
6538                                                 element = BitConverter.GetBytes ((float) v);
6539
6540                                                 for (int j = 0; j < factor; ++j)
6541                                                         data [idx + j] = element [j];
6542                                         }
6543                                 } else if (underlying_type == TypeManager.double_type) {
6544                                         if (!(v is Expression)){
6545                                                 element = BitConverter.GetBytes ((double) v);
6546
6547                                                 for (int j = 0; j < factor; ++j)
6548                                                         data [idx + j] = element [j];
6549                                         }
6550                                 } else if (underlying_type == TypeManager.char_type){
6551                                         if (!(v is Expression)){
6552                                                 int val = (int) ((char) v);
6553
6554                                                 data [idx] = (byte) (val & 0xff);
6555                                                 data [idx+1] = (byte) (val >> 8);
6556                                         }
6557                                 } else if (underlying_type == TypeManager.short_type){
6558                                         if (!(v is Expression)){
6559                                                 int val = (int) ((short) v);
6560
6561                                                 data [idx] = (byte) (val & 0xff);
6562                                                 data [idx+1] = (byte) (val >> 8);
6563                                         }
6564                                 } else if (underlying_type == TypeManager.ushort_type){
6565                                         if (!(v is Expression)){
6566                                                 int val = (int) ((ushort) v);
6567
6568                                                 data [idx] = (byte) (val & 0xff);
6569                                                 data [idx+1] = (byte) (val >> 8);
6570                                         }
6571                                 } else if (underlying_type == TypeManager.int32_type) {
6572                                         if (!(v is Expression)){
6573                                                 int val = (int) v;
6574
6575                                                 data [idx]   = (byte) (val & 0xff);
6576                                                 data [idx+1] = (byte) ((val >> 8) & 0xff);
6577                                                 data [idx+2] = (byte) ((val >> 16) & 0xff);
6578                                                 data [idx+3] = (byte) (val >> 24);
6579                                         }
6580                                 } else if (underlying_type == TypeManager.uint32_type) {
6581                                         if (!(v is Expression)){
6582                                                 uint val = (uint) v;
6583
6584                                                 data [idx]   = (byte) (val & 0xff);
6585                                                 data [idx+1] = (byte) ((val >> 8) & 0xff);
6586                                                 data [idx+2] = (byte) ((val >> 16) & 0xff);
6587                                                 data [idx+3] = (byte) (val >> 24);
6588                                         }
6589                                 } else if (underlying_type == TypeManager.sbyte_type) {
6590                                         if (!(v is Expression)){
6591                                                 sbyte val = (sbyte) v;
6592                                                 data [idx] = (byte) val;
6593                                         }
6594                                 } else if (underlying_type == TypeManager.byte_type) {
6595                                         if (!(v is Expression)){
6596                                                 byte val = (byte) v;
6597                                                 data [idx] = (byte) val;
6598                                         }
6599                                 } else if (underlying_type == TypeManager.bool_type) {
6600                                         if (!(v is Expression)){
6601                                                 bool val = (bool) v;
6602                                                 data [idx] = (byte) (val ? 1 : 0);
6603                                         }
6604                                 } else if (underlying_type == TypeManager.decimal_type){
6605                                         if (!(v is Expression)){
6606                                                 int [] bits = Decimal.GetBits ((decimal) v);
6607                                                 int p = idx;
6608
6609                                                 // FIXME: For some reason, this doesn't work on the MS runtime.
6610                                                 int [] nbits = new int [4];
6611                                                 nbits [0] = bits [3];
6612                                                 nbits [1] = bits [2];
6613                                                 nbits [2] = bits [0];
6614                                                 nbits [3] = bits [1];
6615
6616                                                 for (int j = 0; j < 4; j++){
6617                                                         data [p++] = (byte) (nbits [j] & 0xff);
6618                                                         data [p++] = (byte) ((nbits [j] >> 8) & 0xff);
6619                                                         data [p++] = (byte) ((nbits [j] >> 16) & 0xff);
6620                                                         data [p++] = (byte) (nbits [j] >> 24);
6621                                                 }
6622                                         }
6623                                 } else
6624                                         throw new Exception ("Unrecognized type in MakeByteBlob: " + underlying_type);
6625
6626                                 idx += factor;
6627                         }
6628
6629                         return data;
6630                 }
6631
6632                 //
6633                 // Emits the initializers for the array
6634                 //
6635                 void EmitStaticInitializers (EmitContext ec)
6636                 {
6637                         //
6638                         // First, the static data
6639                         //
6640                         FieldBuilder fb;
6641                         ILGenerator ig = ec.ig;
6642
6643                         byte [] data = MakeByteBlob (array_data, underlying_type, loc);
6644
6645                         fb = RootContext.MakeStaticData (data);
6646
6647                         ig.Emit (OpCodes.Dup);
6648                         ig.Emit (OpCodes.Ldtoken, fb);
6649                         ig.Emit (OpCodes.Call,
6650                                  TypeManager.void_initializearray_array_fieldhandle);
6651                 }
6652
6653                 //
6654                 // Emits pieces of the array that can not be computed at compile
6655                 // time (variables and string locations).
6656                 //
6657                 // This always expect the top value on the stack to be the array
6658                 //
6659                 void EmitDynamicInitializers (EmitContext ec)
6660                 {
6661                         ILGenerator ig = ec.ig;
6662                         int dims = bounds.Count;
6663                         int [] current_pos = new int [dims];
6664                         int top = array_data.Count;
6665
6666                         MethodInfo set = null;
6667
6668                         if (dims != 1){
6669                                 Type [] args;
6670                                 ModuleBuilder mb = null;
6671                                 mb = CodeGen.Module.Builder;
6672                                 args = new Type [dims + 1];
6673
6674                                 int j;
6675                                 for (j = 0; j < dims; j++)
6676                                         args [j] = TypeManager.int32_type;
6677
6678                                 args [j] = array_element_type;
6679
6680                                 set = mb.GetArrayMethod (
6681                                         type, "Set",
6682                                         CallingConventions.HasThis | CallingConventions.Standard,
6683                                         TypeManager.void_type, args);
6684                         }
6685
6686                         for (int i = 0; i < top; i++){
6687
6688                                 Expression e = null;
6689
6690                                 if (array_data [i] is Expression)
6691                                         e = (Expression) array_data [i];
6692
6693                                 if (e != null) {
6694                                         //
6695                                         // Basically we do this for string literals and
6696                                         // other non-literal expressions
6697                                         //
6698                                         if (e is EnumConstant){
6699                                                 e = ((EnumConstant) e).Child;
6700                                         }
6701
6702                                         if (e is StringConstant || e is DecimalConstant || !(e is Constant) ||
6703                                             num_automatic_initializers <= max_automatic_initializers) {
6704                                                 Type etype = e.Type;
6705
6706                                                 ig.Emit (OpCodes.Dup);
6707
6708                                                 for (int idx = 0; idx < dims; idx++)
6709                                                         IntConstant.EmitInt (ig, current_pos [idx]);
6710
6711                                                 //
6712                                                 // If we are dealing with a struct, get the
6713                                                 // address of it, so we can store it.
6714                                                 //
6715                                                 if ((dims == 1) && etype.IsValueType &&
6716                                                     (!TypeManager.IsBuiltinOrEnum (etype) ||
6717                                                      etype == TypeManager.decimal_type)) {
6718                                                         if (e is New){
6719                                                                 New n = (New) e;
6720
6721                                                                 //
6722                                                                 // Let new know that we are providing
6723                                                                 // the address where to store the results
6724                                                                 //
6725                                                                 n.DisableTemporaryValueType ();
6726                                                         }
6727
6728                                                         ig.Emit (OpCodes.Ldelema, etype);
6729                                                 }
6730
6731                                                 e.Emit (ec);
6732
6733                                                 if (dims == 1) {
6734                                                         bool is_stobj, has_type_arg;
6735                                                         OpCode op = ArrayAccess.GetStoreOpcode (
6736                                                                 etype, out is_stobj,
6737                                                                 out has_type_arg);
6738                                                         if (is_stobj)
6739                                                                 ig.Emit (OpCodes.Stobj, etype);
6740                                                         else if (has_type_arg)
6741                                                                 ig.Emit (op, etype);
6742                                                         else
6743                                                                 ig.Emit (op);
6744                                                 } else
6745                                                         ig.Emit (OpCodes.Call, set);
6746                                         }
6747                                 }
6748
6749                                 //
6750                                 // Advance counter
6751                                 //
6752                                 for (int j = dims - 1; j >= 0; j--){
6753                                         current_pos [j]++;
6754                                         if (current_pos [j] < (int) bounds [j])
6755                                                 break;
6756                                         current_pos [j] = 0;
6757                                 }
6758                         }
6759                 }
6760
6761                 void EmitArrayArguments (EmitContext ec)
6762                 {
6763                         ILGenerator ig = ec.ig;
6764
6765                         foreach (Argument a in arguments) {
6766                                 Type atype = a.Type;
6767                                 a.Emit (ec);
6768
6769                                 if (atype == TypeManager.uint64_type)
6770                                         ig.Emit (OpCodes.Conv_Ovf_U4);
6771                                 else if (atype == TypeManager.int64_type)
6772                                         ig.Emit (OpCodes.Conv_Ovf_I4);
6773                         }
6774                 }
6775
6776                 public override void Emit (EmitContext ec)
6777                 {
6778                         ILGenerator ig = ec.ig;
6779
6780                         EmitArrayArguments (ec);
6781                         if (is_one_dimensional)
6782                                 ig.Emit (OpCodes.Newarr, array_element_type);
6783                         else {
6784                                 if (is_builtin_type)
6785                                         ig.Emit (OpCodes.Newobj, (ConstructorInfo) new_method);
6786                                 else
6787                                         ig.Emit (OpCodes.Newobj, (MethodInfo) new_method);
6788                         }
6789
6790                         if (initializers != null){
6791                                 //
6792                                 // FIXME: Set this variable correctly.
6793                                 //
6794                                 bool dynamic_initializers = true;
6795
6796                                 // This will never be true for array types that cannot be statically
6797                                 // initialized. num_automatic_initializers will always be zero.  See
6798                                 // CheckIndices.
6799                                         if (num_automatic_initializers > max_automatic_initializers)
6800                                                 EmitStaticInitializers (ec);
6801
6802                                 if (dynamic_initializers)
6803                                         EmitDynamicInitializers (ec);
6804                         }
6805                 }
6806
6807                 public object EncodeAsAttribute ()
6808                 {
6809                         if (!is_one_dimensional){
6810                                 Report.Error (-211, Location, "attribute can not encode multi-dimensional arrays");
6811                                 return null;
6812                         }
6813
6814                         if (array_data == null){
6815                                 Report.Error (-212, Location, "array should be initialized when passing it to an attribute");
6816                                 return null;
6817                         }
6818
6819                         object [] ret = new object [array_data.Count];
6820                         int i = 0;
6821                         foreach (Expression e in array_data){
6822                                 object v;
6823
6824                                 if (e is NullLiteral)
6825                                         v = null;
6826                                 else {
6827                                         if (!Attribute.GetAttributeArgumentExpression (e, Location, array_element_type, out v))
6828                                                 return null;
6829                                 }
6830                                 ret [i++] = v;
6831                         }
6832                         return ret;
6833                 }
6834         }
6835
6836         /// <summary>
6837         ///   Represents the `this' construct
6838         /// </summary>
6839         public class This : Expression, IAssignMethod, IMemoryLocation, IVariable {
6840
6841                 Block block;
6842                 VariableInfo variable_info;
6843
6844                 public This (Block block, Location loc)
6845                 {
6846                         this.loc = loc;
6847                         this.block = block;
6848                 }
6849
6850                 public This (Location loc)
6851                 {
6852                         this.loc = loc;
6853                 }
6854
6855                 public VariableInfo VariableInfo {
6856                         get { return variable_info; }
6857                 }
6858
6859                 public bool VerifyFixed (bool is_expression)
6860                 {
6861                         if ((variable_info == null) || (variable_info.LocalInfo == null))
6862                                 return false;
6863                         else
6864                                 return variable_info.LocalInfo.IsFixed;
6865                 }
6866
6867                 public bool ResolveBase (EmitContext ec)
6868                 {
6869                         eclass = ExprClass.Variable;
6870
6871                         if (ec.TypeContainer.CurrentType != null)
6872                                 type = ec.TypeContainer.CurrentType;
6873                         else
6874                                 type = ec.ContainerType;
6875
6876                         if (ec.IsStatic) {
6877                                 Error (26, "Keyword this not valid in static code");
6878                                 return false;
6879                         }
6880
6881                         if ((block != null) && (block.ThisVariable != null))
6882                                 variable_info = block.ThisVariable.VariableInfo;
6883
6884                         return true;
6885                 }
6886
6887                 public override Expression DoResolve (EmitContext ec)
6888                 {
6889                         if (!ResolveBase (ec))
6890                                 return null;
6891
6892                         if ((variable_info != null) && !variable_info.IsAssigned (ec)) {
6893                                 Error (188, "The this object cannot be used before all " +
6894                                        "of its fields are assigned to");
6895                                 variable_info.SetAssigned (ec);
6896                                 return this;
6897                         }
6898
6899                         if (ec.IsFieldInitializer) {
6900                                 Error (27, "Keyword `this' can't be used outside a constructor, " +
6901                                        "a method or a property.");
6902                                 return null;
6903                         }
6904
6905                         return this;
6906                 }
6907
6908                 override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
6909                 {
6910                         if (!ResolveBase (ec))
6911                                 return null;
6912
6913                         if (variable_info != null)
6914                                 variable_info.SetAssigned (ec);
6915
6916                         if (ec.TypeContainer is Class){
6917                                 Error (1604, "Cannot assign to `this'");
6918                                 return null;
6919                         }
6920
6921                         return this;
6922                 }
6923
6924                 public void Emit (EmitContext ec, bool leave_copy)
6925                 {
6926                         Emit (ec);
6927                         if (leave_copy)
6928                                 ec.ig.Emit (OpCodes.Dup);
6929                 }
6930
6931                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
6932                 {
6933                         ILGenerator ig = ec.ig;
6934
6935                         if (ec.TypeContainer is Struct){
6936                                 ec.EmitThis ();
6937                                 source.Emit (ec);
6938                                 if (leave_copy)
6939                                         ec.ig.Emit (OpCodes.Dup);
6940                                 ig.Emit (OpCodes.Stobj, type);
6941                         } else {
6942                                 throw new Exception ("how did you get here");
6943                         }
6944                 }
6945
6946                 public override void Emit (EmitContext ec)
6947                 {
6948                         ILGenerator ig = ec.ig;
6949
6950                         ec.EmitThis ();
6951                         if (ec.TypeContainer is Struct)
6952                                 ig.Emit (OpCodes.Ldobj, type);
6953                 }
6954
6955                 public void AddressOf (EmitContext ec, AddressOp mode)
6956                 {
6957                         ec.EmitThis ();
6958
6959                         // FIMXE
6960                         // FIGURE OUT WHY LDARG_S does not work
6961                         //
6962                         // consider: struct X { int val; int P { set { val = value; }}}
6963                         //
6964                         // Yes, this looks very bad. Look at `NOTAS' for
6965                         // an explanation.
6966                         // ec.ig.Emit (OpCodes.Ldarga_S, (byte) 0);
6967                 }
6968         }
6969
6970         /// <summary>
6971         ///   Represents the `__arglist' construct
6972         /// </summary>
6973         public class ArglistAccess : Expression
6974         {
6975                 public ArglistAccess (Location loc)
6976                 {
6977                         this.loc = loc;
6978                 }
6979
6980                 public bool ResolveBase (EmitContext ec)
6981                 {
6982                         eclass = ExprClass.Variable;
6983                         type = TypeManager.runtime_argument_handle_type;
6984                         return true;
6985                 }
6986
6987                 public override Expression DoResolve (EmitContext ec)
6988                 {
6989                         if (!ResolveBase (ec))
6990                                 return null;
6991
6992                         if (ec.IsFieldInitializer || !ec.CurrentBlock.HasVarargs) {
6993                                 Error (190, "The __arglist construct is valid only within " +
6994                                        "a variable argument method.");
6995                                 return null;
6996                         }
6997
6998                         return this;
6999                 }
7000
7001                 public override void Emit (EmitContext ec)
7002                 {
7003                         ec.ig.Emit (OpCodes.Arglist);
7004                 }
7005         }
7006
7007         /// <summary>
7008         ///   Represents the `__arglist (....)' construct
7009         /// </summary>
7010         public class Arglist : Expression
7011         {
7012                 public readonly Argument[] Arguments;
7013
7014                 public Arglist (Argument[] args, Location l)
7015                 {
7016                         Arguments = args;
7017                         loc = l;
7018                 }
7019
7020                 public Type[] ArgumentTypes {
7021                         get {
7022                                 Type[] retval = new Type [Arguments.Length];
7023                                 for (int i = 0; i < Arguments.Length; i++)
7024                                         retval [i] = Arguments [i].Type;
7025                                 return retval;
7026                         }
7027                 }
7028
7029                 public override Expression DoResolve (EmitContext ec)
7030                 {
7031                         eclass = ExprClass.Variable;
7032                         type = TypeManager.runtime_argument_handle_type;
7033
7034                         foreach (Argument arg in Arguments) {
7035                                 if (!arg.Resolve (ec, loc))
7036                                         return null;
7037                         }
7038
7039                         return this;
7040                 }
7041
7042                 public override void Emit (EmitContext ec)
7043                 {
7044                         foreach (Argument arg in Arguments)
7045                                 arg.Emit (ec);
7046                 }
7047         }
7048
7049         //
7050         // This produces the value that renders an instance, used by the iterators code
7051         //
7052         public class ProxyInstance : Expression, IMemoryLocation  {
7053                 public override Expression DoResolve (EmitContext ec)
7054                 {
7055                         eclass = ExprClass.Variable;
7056                         type = ec.ContainerType;
7057                         return this;
7058                 }
7059
7060                 public override void Emit (EmitContext ec)
7061                 {
7062                         ec.ig.Emit (OpCodes.Ldarg_0);
7063
7064                 }
7065
7066                 public void AddressOf (EmitContext ec, AddressOp mode)
7067                 {
7068                         ec.ig.Emit (OpCodes.Ldarg_0);
7069                 }
7070         }
7071
7072         /// <summary>
7073         ///   Implements the typeof operator
7074         /// </summary>
7075         public class TypeOf : Expression {
7076                 public Expression QueriedType;
7077                 protected Type typearg;
7078
7079                 public TypeOf (Expression queried_type, Location l)
7080                 {
7081                         QueriedType = queried_type;
7082                         loc = l;
7083                 }
7084
7085                 public override Expression DoResolve (EmitContext ec)
7086                 {
7087                         TypeExpr texpr = QueriedType.ResolveAsTypeTerminal (ec);
7088                         if (texpr == null)
7089                                 return null;
7090
7091                         typearg = texpr.Type;
7092
7093                         if (typearg == TypeManager.void_type) {
7094                                 Error (673, "System.Void cannot be used from C# - " +
7095                                        "use typeof (void) to get the void type object");
7096                                 return null;
7097                         }
7098
7099                         if (typearg.IsPointer && !ec.InUnsafe){
7100                                 UnsafeError (loc);
7101                                 return null;
7102                         }
7103                         CheckObsoleteAttribute (typearg);
7104
7105                         type = TypeManager.type_type;
7106                         eclass = ExprClass.Type;
7107                         return this;
7108                 }
7109
7110                 public override void Emit (EmitContext ec)
7111                 {
7112                         ec.ig.Emit (OpCodes.Ldtoken, typearg);
7113                         ec.ig.Emit (OpCodes.Call, TypeManager.system_type_get_type_from_handle);
7114                 }
7115
7116                 public Type TypeArg {
7117                         get { return typearg; }
7118                 }
7119         }
7120
7121         /// <summary>
7122         ///   Implements the `typeof (void)' operator
7123         /// </summary>
7124         public class TypeOfVoid : TypeOf {
7125                 public TypeOfVoid (Location l) : base (null, l)
7126                 {
7127                         loc = l;
7128                 }
7129
7130                 public override Expression DoResolve (EmitContext ec)
7131                 {
7132                         type = TypeManager.type_type;
7133                         typearg = TypeManager.void_type;
7134                         eclass = ExprClass.Type;
7135                         return this;
7136                 }
7137         }
7138
7139         /// <summary>
7140         ///   Implements the sizeof expression
7141         /// </summary>
7142         public class SizeOf : Expression {
7143                 public Expression QueriedType;
7144                 Type type_queried;
7145
7146                 public SizeOf (Expression queried_type, Location l)
7147                 {
7148                         this.QueriedType = queried_type;
7149                         loc = l;
7150                 }
7151
7152                 public override Expression DoResolve (EmitContext ec)
7153                 {
7154                         if (!ec.InUnsafe) {
7155                                 Report.Error (
7156                                         233, loc, "Sizeof may only be used in an unsafe context " +
7157                                         "(consider using System.Runtime.InteropServices.Marshal.SizeOf");
7158                                 return null;
7159                         }
7160
7161                         TypeExpr texpr = QueriedType.ResolveAsTypeTerminal (ec);
7162                         if (texpr == null)
7163                                 return null;
7164
7165                         if (texpr is TypeParameterExpr){
7166                                 ((TypeParameterExpr)texpr).Error_CannotUseAsUnmanagedType (loc);
7167                                 return null;
7168                         }
7169
7170                         type_queried = texpr.Type;
7171
7172                         CheckObsoleteAttribute (type_queried);
7173
7174                         if (!TypeManager.IsUnmanagedType (type_queried)){
7175                                 Report.Error (208, loc, "Cannot take the size of an unmanaged type (" + TypeManager.CSharpName (type_queried) + ")");
7176                                 return null;
7177                         }
7178
7179                         type = TypeManager.int32_type;
7180                         eclass = ExprClass.Value;
7181                         return this;
7182                 }
7183
7184                 public override void Emit (EmitContext ec)
7185                 {
7186                         int size = GetTypeSize (type_queried);
7187
7188                         if (size == 0)
7189                                 ec.ig.Emit (OpCodes.Sizeof, type_queried);
7190                         else
7191                                 IntConstant.EmitInt (ec.ig, size);
7192                 }
7193         }
7194
7195         /// <summary>
7196         ///   Implements the member access expression
7197         /// </summary>
7198         public class MemberAccess : Expression {
7199                 public string Identifier;
7200                 protected Expression expr;
7201                 protected TypeArguments args;
7202
7203                 public MemberAccess (Expression expr, string id, Location l)
7204                 {
7205                         this.expr = expr;
7206                         Identifier = id;
7207                         loc = l;
7208                 }
7209
7210                 public MemberAccess (Expression expr, string id, TypeArguments args,
7211                                      Location l)
7212                         : this (expr, id, l)
7213                 {
7214                         this.args = args;
7215                 }
7216
7217                 public Expression Expr {
7218                         get {
7219                                 return expr;
7220                         }
7221                 }
7222
7223                 public static void error176 (Location loc, string name)
7224                 {
7225                         Report.Error (176, loc, "Static member `" +
7226                                       name + "' cannot be accessed " +
7227                                       "with an instance reference, qualify with a " +
7228                                       "type name instead");
7229                 }
7230
7231                 public static bool IdenticalNameAndTypeName (EmitContext ec, Expression left_original, Expression left, Location loc)
7232                 {
7233                         SimpleName sn = left_original as SimpleName;
7234                         if (sn == null || left == null || left.Type.Name != sn.Name)
7235                                 return false;
7236
7237                         return ec.DeclSpace.LookupType (sn.Name, true, loc) != null;
7238                 }
7239
7240                 // TODO: possible optimalization
7241                 // Cache resolved constant result in FieldBuilder <-> expresion map
7242                 public static Expression ResolveMemberAccess (EmitContext ec, Expression member_lookup,
7243                                                               Expression left, Location loc,
7244                                                               Expression left_original)
7245                 {
7246                         bool left_is_type, left_is_explicit;
7247
7248                         // If `left' is null, then we're called from SimpleNameResolve and this is
7249                         // a member in the currently defining class.
7250                         if (left == null) {
7251                                 left_is_type = ec.IsStatic || ec.IsFieldInitializer;
7252                                 left_is_explicit = false;
7253
7254                                 // Implicitly default to `this' unless we're static.
7255                                 if (!ec.IsStatic && !ec.IsFieldInitializer && !ec.InEnumContext)
7256                                         left = ec.GetThis (loc);
7257                         } else {
7258                                 left_is_type = left is TypeExpr;
7259                                 left_is_explicit = true;
7260                         }
7261
7262                         if (member_lookup is FieldExpr){
7263                                 FieldExpr fe = (FieldExpr) member_lookup;
7264                                 FieldInfo fi = fe.FieldInfo.Mono_GetGenericFieldDefinition ();
7265                                 Type decl_type = fi.DeclaringType;
7266
7267                                 bool is_emitted = fi is FieldBuilder;
7268                                 Type t = fi.FieldType;
7269
7270                                 if (is_emitted) {
7271                                         Const c = TypeManager.LookupConstant ((FieldBuilder) fi);
7272
7273                                         if (c != null) {
7274                                                 object o;
7275                                                 if (!c.LookupConstantValue (out o))
7276                                                         return null;
7277
7278                                                 object real_value = ((Constant) c.Expr).GetValue ();
7279
7280                                                 Expression exp = Constantify (real_value, t);
7281
7282                                                 if (left_is_explicit && !left_is_type && !IdenticalNameAndTypeName (ec, left_original, left, loc)) {
7283                                                         Report.SymbolRelatedToPreviousError (c);
7284                                                         error176 (loc, c.GetSignatureForError ());
7285                                                         return null;
7286                                                 }
7287
7288                                                 return exp;
7289                                         }
7290                                 }
7291
7292                                 // IsInitOnly is because of MS compatibility, I don't know why but they emit decimal constant as InitOnly
7293                                 if (fi.IsInitOnly && !is_emitted && t == TypeManager.decimal_type) {
7294                                         object[] attrs = fi.GetCustomAttributes (TypeManager.decimal_constant_attribute_type, false);
7295                                         if (attrs.Length == 1)
7296                                                 return new DecimalConstant (((System.Runtime.CompilerServices.DecimalConstantAttribute) attrs [0]).Value);
7297                                 }
7298
7299                                 if (fi.IsLiteral) {
7300                                         object o;
7301
7302                                         if (is_emitted)
7303                                                 o = TypeManager.GetValue ((FieldBuilder) fi);
7304                                         else
7305                                                 o = fi.GetValue (fi);
7306
7307                                         if (decl_type.IsSubclassOf (TypeManager.enum_type)) {
7308                                                 if (left_is_explicit && !left_is_type &&
7309                                                     !IdenticalNameAndTypeName (ec, left_original, member_lookup, loc)) {
7310                                                         error176 (loc, fe.FieldInfo.Name);
7311                                                         return null;
7312                                                 }
7313
7314                                                 Expression enum_member = MemberLookup (
7315                                                         ec, decl_type, "value__", MemberTypes.Field,
7316                                                         AllBindingFlags, loc);
7317
7318                                                 Enum en = TypeManager.LookupEnum (decl_type);
7319
7320                                                 Constant c;
7321                                                 if (en != null)
7322                                                         c = Constantify (o, en.UnderlyingType);
7323                                                 else
7324                                                         c = Constantify (o, enum_member.Type);
7325
7326                                                 return new EnumConstant (c, decl_type);
7327                                         }
7328
7329                                         Expression exp = Constantify (o, t);
7330
7331                                         if (left_is_explicit && !left_is_type) {
7332                                                 error176 (loc, fe.FieldInfo.Name);
7333                                                 return null;
7334                                         }
7335
7336                                         return exp;
7337                                 }
7338
7339                                 if (t.IsPointer && !ec.InUnsafe){
7340                                         UnsafeError (loc);
7341                                         return null;
7342                                 }
7343                         }
7344
7345                         if (member_lookup is EventExpr) {
7346                                 EventExpr ee = (EventExpr) member_lookup;
7347
7348                                 //
7349                                 // If the event is local to this class, we transform ourselves into
7350                                 // a FieldExpr
7351                                 //
7352
7353                                 if (ee.EventInfo.DeclaringType == ec.ContainerType ||
7354                                     TypeManager.IsNestedChildOf(ec.ContainerType, ee.EventInfo.DeclaringType)) {
7355                                         MemberInfo mi = GetFieldFromEvent (ee);
7356
7357                                         if (mi == null) {
7358                                                 //
7359                                                 // If this happens, then we have an event with its own
7360                                                 // accessors and private field etc so there's no need
7361                                                 // to transform ourselves.
7362                                                 //
7363                                                 ee.InstanceExpression = left;
7364                                                 return ee;
7365                                         }
7366
7367                                         Expression ml = ExprClassFromMemberInfo (ec, mi, loc);
7368
7369                                         if (ml == null) {
7370                                                 Report.Error (-200, loc, "Internal error!!");
7371                                                 return null;
7372                                         }
7373
7374                                         if (!left_is_explicit)
7375                                                 left = null;
7376
7377                                         ee.InstanceExpression = left;
7378
7379                                         return ResolveMemberAccess (ec, ml, left, loc, left_original);
7380                                 }
7381                         }
7382
7383                         if (member_lookup is IMemberExpr) {
7384                                 IMemberExpr me = (IMemberExpr) member_lookup;
7385                                 MethodGroupExpr mg = me as MethodGroupExpr;
7386
7387                                 if (left_is_type){
7388                                         if ((mg != null) && left_is_explicit && left.Type.IsInterface)
7389                                                 mg.IsExplicitImpl = left_is_explicit;
7390
7391                                         if (!me.IsStatic){
7392                                                 if ((ec.IsFieldInitializer || ec.IsStatic) &&
7393                                                     IdenticalNameAndTypeName (ec, left_original, member_lookup, loc))
7394                                                         return member_lookup;
7395
7396                                                 SimpleName.Error_ObjectRefRequired (ec, loc, me.Name);
7397                                                 return null;
7398                                         }
7399
7400                                 } else {
7401                                         if (!me.IsInstance){
7402                                                 if (IdenticalNameAndTypeName (ec, left_original, left, loc))
7403                                                         return member_lookup;
7404
7405                                                 if (left_is_explicit) {
7406                                                         error176 (loc, me.Name);
7407                                                         return null;
7408                                                 }
7409                                         }
7410
7411                                         //
7412                                         // Since we can not check for instance objects in SimpleName,
7413                                         // becaue of the rule that allows types and variables to share
7414                                         // the name (as long as they can be de-ambiguated later, see
7415                                         // IdenticalNameAndTypeName), we have to check whether left
7416                                         // is an instance variable in a static context
7417                                         //
7418                                         // However, if the left-hand value is explicitly given, then
7419                                         // it is already our instance expression, so we aren't in
7420                                         // static context.
7421                                         //
7422
7423                                         if (ec.IsStatic && !left_is_explicit && left is IMemberExpr){
7424                                                 IMemberExpr mexp = (IMemberExpr) left;
7425
7426                                                 if (!mexp.IsStatic){
7427                                                         SimpleName.Error_ObjectRefRequired (ec, loc, mexp.Name);
7428                                                         return null;
7429                                                 }
7430                                         }
7431
7432                                         if ((mg != null) && IdenticalNameAndTypeName (ec, left_original, left, loc))
7433                                                 mg.IdenticalTypeName = true;
7434
7435                                         me.InstanceExpression = left;
7436                                 }
7437
7438                                 return member_lookup;
7439                         }
7440
7441                         Console.WriteLine ("Left is: " + left);
7442                         Report.Error (-100, loc, "Support for [" + member_lookup + "] is not present yet");
7443                         Environment.Exit (1);
7444                         return null;
7445                 }
7446
7447                 public virtual Expression DoResolve (EmitContext ec, Expression right_side,
7448                                                      ResolveFlags flags)
7449                 {
7450                         if (type != null)
7451                                 throw new Exception ();
7452
7453                         //
7454                         // Resolve the expression with flow analysis turned off, we'll do the definite
7455                         // assignment checks later.  This is because we don't know yet what the expression
7456                         // will resolve to - it may resolve to a FieldExpr and in this case we must do the
7457                         // definite assignment check on the actual field and not on the whole struct.
7458                         //
7459
7460                         Expression original = expr;
7461                         expr = expr.Resolve (ec, flags | ResolveFlags.Intermediate | ResolveFlags.DisableFlowAnalysis);
7462                         if (expr == null)
7463                                 return null;
7464
7465                         if (expr is Namespace) {
7466                                 Namespace ns = (Namespace) expr;
7467                                 string lookup_id = MemberName.MakeName (Identifier, args);
7468                                 FullNamedExpression retval = ns.Lookup (ec.DeclSpace, lookup_id, loc);
7469                                 if ((retval != null) && (args != null))
7470                                         retval = new ConstructedType (retval, args, loc).ResolveAsTypeStep (ec);
7471                                 if (retval == null)
7472                                         Report.Error (234, loc, "The type or namespace name `{0}' could not be found in namespace `{1}'", Identifier, ns.FullName);
7473                                 return retval;
7474                         }
7475
7476                         //
7477                         // TODO: I mailed Ravi about this, and apparently we can get rid
7478                         // of this and put it in the right place.
7479                         //
7480                         // Handle enums here when they are in transit.
7481                         // Note that we cannot afford to hit MemberLookup in this case because
7482                         // it will fail to find any members at all
7483                         //
7484
7485                         Type expr_type;
7486                         if (expr is TypeExpr){
7487                                 expr_type = expr.Type;
7488
7489                                 if (!ec.DeclSpace.CheckAccessLevel (expr_type)){
7490                                         Report.Error (122, loc, "'{0}' is inaccessible due to its protection level", expr_type);
7491                                         return null;
7492                                 }
7493
7494                                 if (expr_type == TypeManager.enum_type || expr_type.IsSubclassOf (TypeManager.enum_type)){
7495                                         Enum en = TypeManager.LookupEnum (expr_type);
7496
7497                                         if (en != null) {
7498                                                 object value = en.LookupEnumValue (ec, Identifier, loc);
7499
7500                                                 if (value != null){
7501                                                         MemberCore mc = en.GetDefinition (Identifier);
7502                                                         ObsoleteAttribute oa = mc.GetObsoleteAttribute (en);
7503                                                         if (oa != null) {
7504                                                                 AttributeTester.Report_ObsoleteMessage (oa, mc.GetSignatureForError (), Location);
7505                                                         }
7506                                                         oa = en.GetObsoleteAttribute (en);
7507                                                         if (oa != null) {
7508                                                                 AttributeTester.Report_ObsoleteMessage (oa, en.GetSignatureForError (), Location);
7509                                                         }
7510
7511                                                         Constant c = Constantify (value, en.UnderlyingType);
7512                                                         return new EnumConstant (c, expr_type);
7513                                                 }
7514                                         } else {
7515                                                 CheckObsoleteAttribute (expr_type);
7516
7517                                                 FieldInfo fi = expr_type.GetField (Identifier);
7518                                                 if (fi != null) {
7519                                                         ObsoleteAttribute oa = AttributeTester.GetMemberObsoleteAttribute (fi);
7520                                                         if (oa != null)
7521                                                                 AttributeTester.Report_ObsoleteMessage (oa, TypeManager.GetFullNameSignature (fi), Location);
7522                                                 }
7523                                         }
7524                                 }
7525                         } else
7526                                 expr_type = expr.Type;
7527
7528                         if (expr_type.IsPointer){
7529                                 Error (23, "The `.' operator can not be applied to pointer operands (" +
7530                                        TypeManager.CSharpName (expr_type) + ")");
7531                                 return null;
7532                         }
7533
7534                         Expression member_lookup;
7535                         member_lookup = MemberLookup (
7536                                 ec, expr_type, expr_type, Identifier, loc);
7537                         if ((member_lookup == null) && (args != null)) {
7538                                 string lookup_id = MemberName.MakeName (Identifier, args);
7539                                 member_lookup = MemberLookup (
7540                                         ec, expr_type, expr_type, lookup_id, loc);
7541                         }
7542                         if (member_lookup == null) {
7543                                 MemberLookupFailed (
7544                                         ec, expr_type, expr_type, Identifier, null, loc);
7545                                 return null;
7546                         }
7547
7548                         if (member_lookup is TypeExpr) {
7549                                 if (!(expr is TypeExpr) &&
7550                                     !IdenticalNameAndTypeName (ec, original, expr, loc)) {
7551                                         Error (572, "Can't reference type `" + Identifier + "' through an expression; try `" +
7552                                                member_lookup.Type + "' instead");
7553                                         return null;
7554                                 }
7555
7556                                 return member_lookup;
7557                         }
7558
7559                         if (args != null) {
7560                                 string full_name = expr_type + "." + Identifier;
7561
7562                                 if (member_lookup is FieldExpr) {
7563                                         Report.Error (307, loc, "The field `{0}' cannot " +
7564                                                       "be used with type arguments", full_name);
7565                                         return null;
7566                                 } else if (member_lookup is EventExpr) {
7567                                         Report.Error (307, loc, "The event `{0}' cannot " +
7568                                                       "be used with type arguments", full_name);
7569                                         return null;
7570                                 } else if (member_lookup is PropertyExpr) {
7571                                         Report.Error (307, loc, "The property `{0}' cannot " +
7572                                                       "be used with type arguments", full_name);
7573                                         return null;
7574                                 }
7575                         }
7576
7577                         member_lookup = ResolveMemberAccess (ec, member_lookup, expr, loc, original);
7578                         if (member_lookup == null)
7579                                 return null;
7580
7581                         if (args != null) {
7582                                 MethodGroupExpr mg = member_lookup as MethodGroupExpr;
7583                                 if (mg == null)
7584                                         throw new InternalErrorException ();
7585
7586                                 return mg.ResolveGeneric (ec, args);
7587                         }
7588
7589                         // The following DoResolve/DoResolveLValue will do the definite assignment
7590                         // check.
7591
7592                         if (right_side != null)
7593                                 member_lookup = member_lookup.DoResolveLValue (ec, right_side);
7594                         else
7595                                 member_lookup = member_lookup.DoResolve (ec);
7596
7597                         return member_lookup;
7598                 }
7599
7600                 public override Expression DoResolve (EmitContext ec)
7601                 {
7602                         return DoResolve (ec, null, ResolveFlags.VariableOrValue | ResolveFlags.Type);
7603                 }
7604
7605                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
7606                 {
7607                         return DoResolve (ec, right_side, ResolveFlags.VariableOrValue | ResolveFlags.Type);
7608                 }
7609
7610                 public override FullNamedExpression ResolveAsTypeStep (EmitContext ec)
7611                 {
7612                         return ResolveNamespaceOrType (ec, false);
7613                 }
7614
7615                 public FullNamedExpression ResolveNamespaceOrType (EmitContext ec, bool silent)
7616                 {
7617                         FullNamedExpression new_expr = expr.ResolveAsTypeStep (ec);
7618
7619                         if (new_expr == null)
7620                                 return null;
7621
7622                         string lookup_id = MemberName.MakeName (Identifier, args);
7623
7624                         if (new_expr is Namespace) {
7625                                 Namespace ns = (Namespace) new_expr;
7626                                 FullNamedExpression retval = ns.Lookup (ec.DeclSpace, lookup_id, loc);
7627                                 if ((retval != null) && (args != null))
7628                                         retval = new ConstructedType (retval, args, loc).ResolveAsTypeStep (ec);
7629                                 if (!silent && retval == null)
7630                                         Report.Error (234, loc, "The type or namespace name `{0}' could not be found in namespace `{1}'", Identifier, ns.FullName);
7631                                 return retval;
7632                         }
7633
7634                         TypeExpr tnew_expr = new_expr.ResolveAsTypeTerminal (ec);
7635                         if (tnew_expr == null)
7636                                 return null;
7637
7638                         Type expr_type = tnew_expr.Type;
7639
7640                         if (expr_type.IsPointer){
7641                                 Error (23, "The `.' operator can not be applied to pointer operands (" +
7642                                        TypeManager.CSharpName (expr_type) + ")");
7643                                 return null;
7644                         }
7645
7646                         Expression member_lookup;
7647                         member_lookup = MemberLookupFinal (ec, expr_type, expr_type, lookup_id, loc);
7648                         if (!silent && member_lookup == null) {
7649                                 Report.Error (234, loc, "The type name `{0}' could not be found in type `{1}'",
7650                                               Identifier, new_expr.FullName);
7651                                 return null;
7652                         }
7653
7654                         if (!(member_lookup is TypeExpr)) {
7655                                 Report.Error (118, loc, "'{0}.{1}' denotes a '{2}', where a type was expected",
7656                                               new_expr.FullName, Identifier, member_lookup.ExprClassName ());
7657                                 return null;
7658                         }
7659
7660                         TypeExpr texpr = member_lookup.ResolveAsTypeTerminal (ec);
7661                         if (texpr == null)
7662                                 return null;
7663
7664                         TypeArguments the_args = args;
7665                         if (TypeManager.HasGenericArguments (expr_type)) {
7666                                 Type[] decl_args = TypeManager.GetTypeArguments (expr_type);
7667
7668                                 TypeArguments new_args = new TypeArguments (loc);
7669                                 foreach (Type decl in decl_args)
7670                                         new_args.Add (new TypeExpression (decl, loc));
7671
7672                                 if (args != null)
7673                                         new_args.Add (args);
7674
7675                                 the_args = new_args;
7676                         }
7677
7678                         if (the_args != null) {
7679                                 ConstructedType ctype = new ConstructedType (texpr.Type, the_args, loc);
7680                                 return ctype.ResolveAsTypeStep (ec);
7681                         }
7682
7683                         return texpr;
7684                 }
7685
7686                 public override void Emit (EmitContext ec)
7687                 {
7688                         throw new Exception ("Should not happen");
7689                 }
7690
7691                 public override string ToString ()
7692                 {
7693                         return expr + "." + MemberName.MakeName (Identifier, args);
7694                 }
7695         }
7696
7697         /// <summary>
7698         ///   Implements checked expressions
7699         /// </summary>
7700         public class CheckedExpr : Expression {
7701
7702                 public Expression Expr;
7703
7704                 public CheckedExpr (Expression e, Location l)
7705                 {
7706                         Expr = e;
7707                         loc = l;
7708                 }
7709
7710                 public override Expression DoResolve (EmitContext ec)
7711                 {
7712                         bool last_check = ec.CheckState;
7713                         bool last_const_check = ec.ConstantCheckState;
7714
7715                         ec.CheckState = true;
7716                         ec.ConstantCheckState = true;
7717                         Expr = Expr.Resolve (ec);
7718                         ec.CheckState = last_check;
7719                         ec.ConstantCheckState = last_const_check;
7720
7721                         if (Expr == null)
7722                                 return null;
7723
7724                         if (Expr is Constant)
7725                                 return Expr;
7726
7727                         eclass = Expr.eclass;
7728                         type = Expr.Type;
7729                         return this;
7730                 }
7731
7732                 public override void Emit (EmitContext ec)
7733                 {
7734                         bool last_check = ec.CheckState;
7735                         bool last_const_check = ec.ConstantCheckState;
7736
7737                         ec.CheckState = true;
7738                         ec.ConstantCheckState = true;
7739                         Expr.Emit (ec);
7740                         ec.CheckState = last_check;
7741                         ec.ConstantCheckState = last_const_check;
7742                 }
7743
7744         }
7745
7746         /// <summary>
7747         ///   Implements the unchecked expression
7748         /// </summary>
7749         public class UnCheckedExpr : Expression {
7750
7751                 public Expression Expr;
7752
7753                 public UnCheckedExpr (Expression e, Location l)
7754                 {
7755                         Expr = e;
7756                         loc = l;
7757                 }
7758
7759                 public override Expression DoResolve (EmitContext ec)
7760                 {
7761                         bool last_check = ec.CheckState;
7762                         bool last_const_check = ec.ConstantCheckState;
7763
7764                         ec.CheckState = false;
7765                         ec.ConstantCheckState = false;
7766                         Expr = Expr.Resolve (ec);
7767                         ec.CheckState = last_check;
7768                         ec.ConstantCheckState = last_const_check;
7769
7770                         if (Expr == null)
7771                                 return null;
7772
7773                         if (Expr is Constant)
7774                                 return Expr;
7775
7776                         eclass = Expr.eclass;
7777                         type = Expr.Type;
7778                         return this;
7779                 }
7780
7781                 public override void Emit (EmitContext ec)
7782                 {
7783                         bool last_check = ec.CheckState;
7784                         bool last_const_check = ec.ConstantCheckState;
7785
7786                         ec.CheckState = false;
7787                         ec.ConstantCheckState = false;
7788                         Expr.Emit (ec);
7789                         ec.CheckState = last_check;
7790                         ec.ConstantCheckState = last_const_check;
7791                 }
7792
7793         }
7794
7795         /// <summary>
7796         ///   An Element Access expression.
7797         ///
7798         ///   During semantic analysis these are transformed into
7799         ///   IndexerAccess, ArrayAccess or a PointerArithmetic.
7800         /// </summary>
7801         public class ElementAccess : Expression {
7802                 public ArrayList  Arguments;
7803                 public Expression Expr;
7804
7805                 public ElementAccess (Expression e, ArrayList e_list, Location l)
7806                 {
7807                         Expr = e;
7808
7809                         loc  = l;
7810
7811                         if (e_list == null)
7812                                 return;
7813
7814                         Arguments = new ArrayList ();
7815                         foreach (Expression tmp in e_list)
7816                                 Arguments.Add (new Argument (tmp, Argument.AType.Expression));
7817
7818                 }
7819
7820                 bool CommonResolve (EmitContext ec)
7821                 {
7822                         Expr = Expr.Resolve (ec);
7823
7824                         if (Expr == null)
7825                                 return false;
7826
7827                         if (Arguments == null)
7828                                 return false;
7829
7830                         foreach (Argument a in Arguments){
7831                                 if (!a.Resolve (ec, loc))
7832                                         return false;
7833                         }
7834
7835                         return true;
7836                 }
7837
7838                 Expression MakePointerAccess (EmitContext ec)
7839                 {
7840                         Type t = Expr.Type;
7841
7842                         if (t == TypeManager.void_ptr_type){
7843                                 Error (242, "The array index operation is not valid for void pointers");
7844                                 return null;
7845                         }
7846                         if (Arguments.Count != 1){
7847                                 Error (196, "A pointer must be indexed by a single value");
7848                                 return null;
7849                         }
7850                         Expression p;
7851
7852                         p = new PointerArithmetic (true, Expr, ((Argument)Arguments [0]).Expr, t, loc).Resolve (ec);
7853                         if (p == null)
7854                                 return null;
7855                         return new Indirection (p, loc).Resolve (ec);
7856                 }
7857
7858                 public override Expression DoResolve (EmitContext ec)
7859                 {
7860                         if (!CommonResolve (ec))
7861                                 return null;
7862
7863                         //
7864                         // We perform some simple tests, and then to "split" the emit and store
7865                         // code we create an instance of a different class, and return that.
7866                         //
7867                         // I am experimenting with this pattern.
7868                         //
7869                         Type t = Expr.Type;
7870
7871                         if (t == TypeManager.array_type){
7872                                 Report.Error (21, loc, "Cannot use indexer on System.Array");
7873                                 return null;
7874                         }
7875
7876                         if (t.IsArray)
7877                                 return (new ArrayAccess (this, loc)).Resolve (ec);
7878                         else if (t.IsPointer)
7879                                 return MakePointerAccess (ec);
7880                         else
7881                                 return (new IndexerAccess (this, loc)).Resolve (ec);
7882                 }
7883
7884                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
7885                 {
7886                         if (!CommonResolve (ec))
7887                                 return null;
7888
7889                         Type t = Expr.Type;
7890                         if (t.IsArray)
7891                                 return (new ArrayAccess (this, loc)).ResolveLValue (ec, right_side);
7892                         else if (t.IsPointer)
7893                                 return MakePointerAccess (ec);
7894                         else
7895                                 return (new IndexerAccess (this, loc)).ResolveLValue (ec, right_side);
7896                 }
7897
7898                 public override void Emit (EmitContext ec)
7899                 {
7900                         throw new Exception ("Should never be reached");
7901                 }
7902         }
7903
7904         /// <summary>
7905         ///   Implements array access
7906         /// </summary>
7907         public class ArrayAccess : Expression, IAssignMethod, IMemoryLocation {
7908                 //
7909                 // Points to our "data" repository
7910                 //
7911                 ElementAccess ea;
7912
7913                 LocalTemporary temp;
7914                 bool prepared;
7915
7916                 public ArrayAccess (ElementAccess ea_data, Location l)
7917                 {
7918                         ea = ea_data;
7919                         eclass = ExprClass.Variable;
7920                         loc = l;
7921                 }
7922
7923                 public override Expression DoResolve (EmitContext ec)
7924                 {
7925 #if false
7926                         ExprClass eclass = ea.Expr.eclass;
7927
7928                         // As long as the type is valid
7929                         if (!(eclass == ExprClass.Variable || eclass == ExprClass.PropertyAccess ||
7930                               eclass == ExprClass.Value)) {
7931                                 ea.Expr.Error_UnexpectedKind ("variable or value");
7932                                 return null;
7933                         }
7934 #endif
7935
7936                         Type t = ea.Expr.Type;
7937                         if (t.GetArrayRank () != ea.Arguments.Count){
7938                                 ea.Error (22,
7939                                           "Incorrect number of indexes for array " +
7940                                           " expected: " + t.GetArrayRank () + " got: " +
7941                                           ea.Arguments.Count);
7942                                 return null;
7943                         }
7944
7945                         type = TypeManager.GetElementType (t);
7946                         if (type.IsPointer && !ec.InUnsafe){
7947                                 UnsafeError (ea.Location);
7948                                 return null;
7949                         }
7950
7951                         foreach (Argument a in ea.Arguments){
7952                                 Type argtype = a.Type;
7953
7954                                 if (argtype == TypeManager.int32_type ||
7955                                     argtype == TypeManager.uint32_type ||
7956                                     argtype == TypeManager.int64_type ||
7957                                     argtype == TypeManager.uint64_type) {
7958                                         Constant c = a.Expr as Constant;
7959                                         if (c != null && c.IsNegative) {
7960                                                 Report.Warning (251, 2, a.Expr.Location, "Indexing an array with a negative index (array indices always start at zero)");
7961                                         }
7962                                         continue;
7963                                 }
7964
7965                                 //
7966                                 // Mhm.  This is strage, because the Argument.Type is not the same as
7967                                 // Argument.Expr.Type: the value changes depending on the ref/out setting.
7968                                 //
7969                                 // Wonder if I will run into trouble for this.
7970                                 //
7971                                 a.Expr = ExpressionToArrayArgument (ec, a.Expr, ea.Location);
7972                                 if (a.Expr == null)
7973                                         return null;
7974                         }
7975
7976                         eclass = ExprClass.Variable;
7977
7978                         return this;
7979                 }
7980
7981                 /// <summary>
7982                 ///    Emits the right opcode to load an object of Type `t'
7983                 ///    from an array of T
7984                 /// </summary>
7985                 static public void EmitLoadOpcode (ILGenerator ig, Type type)
7986                 {
7987                         if (type == TypeManager.byte_type || type == TypeManager.bool_type)
7988                                 ig.Emit (OpCodes.Ldelem_U1);
7989                         else if (type == TypeManager.sbyte_type)
7990                                 ig.Emit (OpCodes.Ldelem_I1);
7991                         else if (type == TypeManager.short_type)
7992                                 ig.Emit (OpCodes.Ldelem_I2);
7993                         else if (type == TypeManager.ushort_type || type == TypeManager.char_type)
7994                                 ig.Emit (OpCodes.Ldelem_U2);
7995                         else if (type == TypeManager.int32_type)
7996                                 ig.Emit (OpCodes.Ldelem_I4);
7997                         else if (type == TypeManager.uint32_type)
7998                                 ig.Emit (OpCodes.Ldelem_U4);
7999                         else if (type == TypeManager.uint64_type)
8000                                 ig.Emit (OpCodes.Ldelem_I8);
8001                         else if (type == TypeManager.int64_type)
8002                                 ig.Emit (OpCodes.Ldelem_I8);
8003                         else if (type == TypeManager.float_type)
8004                                 ig.Emit (OpCodes.Ldelem_R4);
8005                         else if (type == TypeManager.double_type)
8006                                 ig.Emit (OpCodes.Ldelem_R8);
8007                         else if (type == TypeManager.intptr_type)
8008                                 ig.Emit (OpCodes.Ldelem_I);
8009                         else if (TypeManager.IsEnumType (type)){
8010                                 EmitLoadOpcode (ig, TypeManager.EnumToUnderlying (type));
8011                         } else if (type.IsValueType){
8012                                 ig.Emit (OpCodes.Ldelema, type);
8013                                 ig.Emit (OpCodes.Ldobj, type);
8014                         } else if (type.IsGenericParameter)
8015                                 ig.Emit (OpCodes.Ldelem_Any, type);
8016                         else
8017                                 ig.Emit (OpCodes.Ldelem_Ref);
8018                 }
8019
8020                 /// <summary>
8021                 ///    Returns the right opcode to store an object of Type `t'
8022                 ///    from an array of T.
8023                 /// </summary>
8024                 static public OpCode GetStoreOpcode (Type t, out bool is_stobj, out bool has_type_arg)
8025                 {
8026                         //Console.WriteLine (new System.Diagnostics.StackTrace ());
8027                         has_type_arg = false; is_stobj = false;
8028                         t = TypeManager.TypeToCoreType (t);
8029                         if (TypeManager.IsEnumType (t))
8030                                 t = TypeManager.EnumToUnderlying (t);
8031                         if (t == TypeManager.byte_type || t == TypeManager.sbyte_type ||
8032                             t == TypeManager.bool_type)
8033                                 return OpCodes.Stelem_I1;
8034                         else if (t == TypeManager.short_type || t == TypeManager.ushort_type ||
8035                                  t == TypeManager.char_type)
8036                                 return OpCodes.Stelem_I2;
8037                         else if (t == TypeManager.int32_type || t == TypeManager.uint32_type)
8038                                 return OpCodes.Stelem_I4;
8039                         else if (t == TypeManager.int64_type || t == TypeManager.uint64_type)
8040                                 return OpCodes.Stelem_I8;
8041                         else if (t == TypeManager.float_type)
8042                                 return OpCodes.Stelem_R4;
8043                         else if (t == TypeManager.double_type)
8044                                 return OpCodes.Stelem_R8;
8045                         else if (t == TypeManager.intptr_type) {
8046                                 has_type_arg = true;
8047                                 is_stobj = true;
8048                                 return OpCodes.Stobj;
8049                         } else if (t.IsValueType) {
8050                                 has_type_arg = true;
8051                                 is_stobj = true;
8052                                 return OpCodes.Stobj;
8053                         } else if (t.IsGenericParameter) {
8054                                 has_type_arg = true;
8055                                 return OpCodes.Stelem_Any;
8056                         } else
8057                                 return OpCodes.Stelem_Ref;
8058                 }
8059
8060                 MethodInfo FetchGetMethod ()
8061                 {
8062                         ModuleBuilder mb = CodeGen.Module.Builder;
8063                         int arg_count = ea.Arguments.Count;
8064                         Type [] args = new Type [arg_count];
8065                         MethodInfo get;
8066
8067                         for (int i = 0; i < arg_count; i++){
8068                                 //args [i++] = a.Type;
8069                                 args [i] = TypeManager.int32_type;
8070                         }
8071
8072                         get = mb.GetArrayMethod (
8073                                 ea.Expr.Type, "Get",
8074                                 CallingConventions.HasThis |
8075                                 CallingConventions.Standard,
8076                                 type, args);
8077                         return get;
8078                 }
8079
8080
8081                 MethodInfo FetchAddressMethod ()
8082                 {
8083                         ModuleBuilder mb = CodeGen.Module.Builder;
8084                         int arg_count = ea.Arguments.Count;
8085                         Type [] args = new Type [arg_count];
8086                         MethodInfo address;
8087                         Type ret_type;
8088
8089                         ret_type = TypeManager.GetReferenceType (type);
8090
8091                         for (int i = 0; i < arg_count; i++){
8092                                 //args [i++] = a.Type;
8093                                 args [i] = TypeManager.int32_type;
8094                         }
8095
8096                         address = mb.GetArrayMethod (
8097                                 ea.Expr.Type, "Address",
8098                                 CallingConventions.HasThis |
8099                                 CallingConventions.Standard,
8100                                 ret_type, args);
8101
8102                         return address;
8103                 }
8104
8105                 //
8106                 // Load the array arguments into the stack.
8107                 //
8108                 // If we have been requested to cache the values (cached_locations array
8109                 // initialized), then load the arguments the first time and store them
8110                 // in locals.  otherwise load from local variables.
8111                 //
8112                 void LoadArrayAndArguments (EmitContext ec)
8113                 {
8114                         ILGenerator ig = ec.ig;
8115
8116                         ea.Expr.Emit (ec);
8117                         foreach (Argument a in ea.Arguments){
8118                                 Type argtype = a.Expr.Type;
8119
8120                                 a.Expr.Emit (ec);
8121
8122                                 if (argtype == TypeManager.int64_type)
8123                                         ig.Emit (OpCodes.Conv_Ovf_I);
8124                                 else if (argtype == TypeManager.uint64_type)
8125                                         ig.Emit (OpCodes.Conv_Ovf_I_Un);
8126                         }
8127                 }
8128
8129                 public void Emit (EmitContext ec, bool leave_copy)
8130                 {
8131                         int rank = ea.Expr.Type.GetArrayRank ();
8132                         ILGenerator ig = ec.ig;
8133
8134                         if (!prepared) {
8135                                 LoadArrayAndArguments (ec);
8136
8137                                 if (rank == 1)
8138                                         EmitLoadOpcode (ig, type);
8139                                 else {
8140                                         MethodInfo method;
8141
8142                                         method = FetchGetMethod ();
8143                                         ig.Emit (OpCodes.Call, method);
8144                                 }
8145                         } else
8146                                 LoadFromPtr (ec.ig, this.type);
8147
8148                         if (leave_copy) {
8149                                 ec.ig.Emit (OpCodes.Dup);
8150                                 temp = new LocalTemporary (ec, this.type);
8151                                 temp.Store (ec);
8152                         }
8153                 }
8154
8155                 public override void Emit (EmitContext ec)
8156                 {
8157                         Emit (ec, false);
8158                 }
8159
8160                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
8161                 {
8162                         int rank = ea.Expr.Type.GetArrayRank ();
8163                         ILGenerator ig = ec.ig;
8164                         Type t = source.Type;
8165                         prepared = prepare_for_load;
8166
8167                         if (prepare_for_load) {
8168                                 AddressOf (ec, AddressOp.LoadStore);
8169                                 ec.ig.Emit (OpCodes.Dup);
8170                                 source.Emit (ec);
8171                                 if (leave_copy) {
8172                                         ec.ig.Emit (OpCodes.Dup);
8173                                         temp = new LocalTemporary (ec, this.type);
8174                                         temp.Store (ec);
8175                                 }
8176                                 StoreFromPtr (ec.ig, t);
8177
8178                                 if (temp != null)
8179                                         temp.Emit (ec);
8180
8181                                 return;
8182                         }
8183
8184                         LoadArrayAndArguments (ec);
8185
8186                         if (rank == 1) {
8187                                 bool is_stobj, has_type_arg;
8188                                 OpCode op = GetStoreOpcode (t, out is_stobj, out has_type_arg);
8189
8190                                 //
8191                                 // The stobj opcode used by value types will need
8192                                 // an address on the stack, not really an array/array
8193                                 // pair
8194                                 //
8195                                 if (is_stobj)
8196                                         ig.Emit (OpCodes.Ldelema, t);
8197
8198                                 source.Emit (ec);
8199                                 if (leave_copy) {
8200                                         ec.ig.Emit (OpCodes.Dup);
8201                                         temp = new LocalTemporary (ec, this.type);
8202                                         temp.Store (ec);
8203                                 }
8204
8205                                 if (is_stobj)
8206                                         ig.Emit (OpCodes.Stobj, t);
8207                                 else if (has_type_arg)
8208                                         ig.Emit (op, t);
8209                                 else
8210                                         ig.Emit (op);
8211                         } else {
8212                                 ModuleBuilder mb = CodeGen.Module.Builder;
8213                                 int arg_count = ea.Arguments.Count;
8214                                 Type [] args = new Type [arg_count + 1];
8215                                 MethodInfo set;
8216
8217                                 source.Emit (ec);
8218                                 if (leave_copy) {
8219                                         ec.ig.Emit (OpCodes.Dup);
8220                                         temp = new LocalTemporary (ec, this.type);
8221                                         temp.Store (ec);
8222                                 }
8223
8224                                 for (int i = 0; i < arg_count; i++){
8225                                         //args [i++] = a.Type;
8226                                         args [i] = TypeManager.int32_type;
8227                                 }
8228
8229                                 args [arg_count] = type;
8230
8231                                 set = mb.GetArrayMethod (
8232                                         ea.Expr.Type, "Set",
8233                                         CallingConventions.HasThis |
8234                                         CallingConventions.Standard,
8235                                         TypeManager.void_type, args);
8236
8237                                 ig.Emit (OpCodes.Call, set);
8238                         }
8239
8240                         if (temp != null)
8241                                 temp.Emit (ec);
8242                 }
8243
8244                 public void AddressOf (EmitContext ec, AddressOp mode)
8245                 {
8246                         int rank = ea.Expr.Type.GetArrayRank ();
8247                         ILGenerator ig = ec.ig;
8248
8249                         LoadArrayAndArguments (ec);
8250
8251                         if (rank == 1){
8252                                 ig.Emit (OpCodes.Ldelema, type);
8253                         } else {
8254                                 MethodInfo address = FetchAddressMethod ();
8255                                 ig.Emit (OpCodes.Call, address);
8256                         }
8257                 }
8258         }
8259
8260
8261         class Indexers {
8262                 public ArrayList Properties;
8263                 static Hashtable map;
8264
8265                 public struct Indexer {
8266                         public readonly Type Type;
8267                         public readonly MethodInfo Getter, Setter;
8268
8269                         public Indexer (Type type, MethodInfo get, MethodInfo set)
8270                         {
8271                                 this.Type = type;
8272                                 this.Getter = get;
8273                                 this.Setter = set;
8274                         }
8275                 }
8276
8277                 static Indexers ()
8278                 {
8279                         map = new Hashtable ();
8280                 }
8281
8282                 Indexers ()
8283                 {
8284                         Properties = new ArrayList ();
8285                 }
8286
8287                 void Append (MemberInfo [] mi)
8288                 {
8289                         foreach (PropertyInfo property in mi){
8290                                 MethodInfo get, set;
8291
8292                                 get = property.GetGetMethod (true);
8293                                 set = property.GetSetMethod (true);
8294                                 Properties.Add (new Indexer (property.PropertyType, get, set));
8295                         }
8296                 }
8297
8298                 static private MemberInfo [] GetIndexersForTypeOrInterface (Type caller_type, Type lookup_type)
8299                 {
8300                         string p_name = TypeManager.IndexerPropertyName (lookup_type);
8301
8302                         MemberInfo [] mi = TypeManager.MemberLookup (
8303                                 caller_type, caller_type, lookup_type, MemberTypes.Property,
8304                                 BindingFlags.Public | BindingFlags.Instance |
8305                                 BindingFlags.DeclaredOnly, p_name, null);
8306
8307                         if (mi == null || mi.Length == 0)
8308                                 return null;
8309
8310                         return mi;
8311                 }
8312
8313                 static public Indexers GetIndexersForType (Type caller_type, Type lookup_type, Location loc)
8314                 {
8315                         Indexers ix = (Indexers) map [lookup_type];
8316
8317                         if (ix != null)
8318                                 return ix;
8319
8320                         Type copy = lookup_type;
8321                         while (copy != TypeManager.object_type && copy != null){
8322                                 MemberInfo [] mi = GetIndexersForTypeOrInterface (caller_type, copy);
8323
8324                                 if (mi != null){
8325                                         if (ix == null)
8326                                                 ix = new Indexers ();
8327
8328                                         ix.Append (mi);
8329                                 }
8330
8331                                 copy = copy.BaseType;
8332                         }
8333
8334                         if (!lookup_type.IsInterface)
8335                                 return ix;
8336
8337                         Type [] ifaces = TypeManager.GetInterfaces (lookup_type);
8338                         if (ifaces != null) {
8339                                 foreach (Type itype in ifaces) {
8340                                         MemberInfo [] mi = GetIndexersForTypeOrInterface (caller_type, itype);
8341                                         if (mi != null){
8342                                                 if (ix == null)
8343                                                         ix = new Indexers ();
8344
8345                                                 ix.Append (mi);
8346                                         }
8347                                 }
8348                         }
8349
8350                         return ix;
8351                 }
8352         }
8353
8354         /// <summary>
8355         ///   Expressions that represent an indexer call.
8356         /// </summary>
8357         public class IndexerAccess : Expression, IAssignMethod {
8358                 //
8359                 // Points to our "data" repository
8360                 //
8361                 MethodInfo get, set;
8362                 ArrayList set_arguments;
8363                 bool is_base_indexer;
8364
8365                 protected Type indexer_type;
8366                 protected Type current_type;
8367                 protected Expression instance_expr;
8368                 protected ArrayList arguments;
8369
8370                 public IndexerAccess (ElementAccess ea, Location loc)
8371                         : this (ea.Expr, false, loc)
8372                 {
8373                         this.arguments = ea.Arguments;
8374                 }
8375
8376                 protected IndexerAccess (Expression instance_expr, bool is_base_indexer,
8377                                          Location loc)
8378                 {
8379                         this.instance_expr = instance_expr;
8380                         this.is_base_indexer = is_base_indexer;
8381                         this.eclass = ExprClass.Value;
8382                         this.loc = loc;
8383                 }
8384
8385                 protected virtual bool CommonResolve (EmitContext ec)
8386                 {
8387                         indexer_type = instance_expr.Type;
8388                         current_type = ec.ContainerType;
8389
8390                         return true;
8391                 }
8392
8393                 public override Expression DoResolve (EmitContext ec)
8394                 {
8395                         ArrayList AllGetters = new ArrayList();
8396                         if (!CommonResolve (ec))
8397                                 return null;
8398
8399                         //
8400                         // Step 1: Query for all `Item' *properties*.  Notice
8401                         // that the actual methods are pointed from here.
8402                         //
8403                         // This is a group of properties, piles of them.
8404
8405                         bool found_any = false, found_any_getters = false;
8406                         Type lookup_type = indexer_type;
8407
8408                         Indexers ilist;
8409                         ilist = Indexers.GetIndexersForType (current_type, lookup_type, loc);
8410                         if (ilist != null) {
8411                                 found_any = true;
8412                                 if (ilist.Properties != null) {
8413                                         foreach (Indexers.Indexer ix in ilist.Properties) {
8414                                                 if (ix.Getter != null)
8415                                                         AllGetters.Add(ix.Getter);
8416                                         }
8417                                 }
8418                         }
8419
8420                         if (AllGetters.Count > 0) {
8421                                 found_any_getters = true;
8422                                 get = (MethodInfo) Invocation.OverloadResolve (
8423                                         ec, new MethodGroupExpr (AllGetters, loc),
8424                                         arguments, false, loc);
8425                         }
8426
8427                         if (!found_any) {
8428                                 Report.Error (21, loc,
8429                                               "Type `" + TypeManager.CSharpName (indexer_type) +
8430                                               "' does not have any indexers defined");
8431                                 return null;
8432                         }
8433
8434                         if (!found_any_getters) {
8435                                 Error (154, "indexer can not be used in this context, because " +
8436                                        "it lacks a `get' accessor");
8437                                 return null;
8438                         }
8439
8440                         if (get == null) {
8441                                 Error (1501, "No Overload for method `this' takes `" +
8442                                        arguments.Count + "' arguments");
8443                                 return null;
8444                         }
8445
8446                         //
8447                         // Only base will allow this invocation to happen.
8448                         //
8449                         if (get.IsAbstract && this is BaseIndexerAccess){
8450                                 Report.Error (205, loc, "Cannot call an abstract base indexer: " + Invocation.FullMethodDesc (get));
8451                                 return null;
8452                         }
8453
8454                         type = get.ReturnType;
8455                         if (type.IsPointer && !ec.InUnsafe){
8456                                 UnsafeError (loc);
8457                                 return null;
8458                         }
8459
8460                         instance_expr.CheckMarshallByRefAccess (ec.ContainerType);
8461
8462                         eclass = ExprClass.IndexerAccess;
8463                         return this;
8464                 }
8465
8466                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
8467                 {
8468                         ArrayList AllSetters = new ArrayList();
8469                         if (!CommonResolve (ec))
8470                                 return null;
8471
8472                         bool found_any = false, found_any_setters = false;
8473
8474                         Indexers ilist = Indexers.GetIndexersForType (current_type, indexer_type, loc);
8475                         if (ilist != null) {
8476                                 found_any = true;
8477                                 if (ilist.Properties != null) {
8478                                         foreach (Indexers.Indexer ix in ilist.Properties) {
8479                                                 if (ix.Setter != null)
8480                                                         AllSetters.Add(ix.Setter);
8481                                         }
8482                                 }
8483                         }
8484                         if (AllSetters.Count > 0) {
8485                                 found_any_setters = true;
8486                                 set_arguments = (ArrayList) arguments.Clone ();
8487                                 set_arguments.Add (new Argument (right_side, Argument.AType.Expression));
8488                                 set = (MethodInfo) Invocation.OverloadResolve (
8489                                         ec, new MethodGroupExpr (AllSetters, loc),
8490                                         set_arguments, false, loc);
8491                         }
8492
8493                         if (!found_any) {
8494                                 Report.Error (21, loc,
8495                                               "Type `" + TypeManager.CSharpName (indexer_type) +
8496                                               "' does not have any indexers defined");
8497                                 return null;
8498                         }
8499
8500                         if (!found_any_setters) {
8501                                 Error (154, "indexer can not be used in this context, because " +
8502                                        "it lacks a `set' accessor");
8503                                 return null;
8504                         }
8505
8506                         if (set == null) {
8507                                 Error (1501, "No Overload for method `this' takes `" +
8508                                        arguments.Count + "' arguments");
8509                                 return null;
8510                         }
8511
8512                         //
8513                         // Only base will allow this invocation to happen.
8514                         //
8515                         if (set.IsAbstract && this is BaseIndexerAccess){
8516                                 Report.Error (205, loc, "Cannot call an abstract base indexer: " + Invocation.FullMethodDesc (set));
8517                                 return null;
8518                         }
8519
8520                         //
8521                         // Now look for the actual match in the list of indexers to set our "return" type
8522                         //
8523                         type = TypeManager.void_type;   // default value
8524                         foreach (Indexers.Indexer ix in ilist.Properties){
8525                                 if (ix.Setter == set){
8526                                         type = ix.Type;
8527                                         break;
8528                                 }
8529                         }
8530
8531                         instance_expr.CheckMarshallByRefAccess (ec.ContainerType);
8532
8533                         eclass = ExprClass.IndexerAccess;
8534                         return this;
8535                 }
8536
8537                 bool prepared = false;
8538                 LocalTemporary temp;
8539
8540                 public void Emit (EmitContext ec, bool leave_copy)
8541                 {
8542                         Invocation.EmitCall (ec, is_base_indexer, false, instance_expr, get, arguments, loc, prepared, false);
8543                         if (leave_copy) {
8544                                 ec.ig.Emit (OpCodes.Dup);
8545                                 temp = new LocalTemporary (ec, Type);
8546                                 temp.Store (ec);
8547                         }
8548                 }
8549
8550                 //
8551                 // source is ignored, because we already have a copy of it from the
8552                 // LValue resolution and we have already constructed a pre-cached
8553                 // version of the arguments (ea.set_arguments);
8554                 //
8555                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
8556                 {
8557                         prepared = prepare_for_load;
8558                         Argument a = (Argument) set_arguments [set_arguments.Count - 1];
8559
8560                         if (prepared) {
8561                                 source.Emit (ec);
8562                                 if (leave_copy) {
8563                                         ec.ig.Emit (OpCodes.Dup);
8564                                         temp = new LocalTemporary (ec, Type);
8565                                         temp.Store (ec);
8566                                 }
8567                         } else if (leave_copy) {
8568                                 temp = new LocalTemporary (ec, Type);
8569                                 source.Emit (ec);
8570                                 temp.Store (ec);
8571                                 a.Expr = temp;
8572                         }
8573
8574                         Invocation.EmitCall (ec, is_base_indexer, false, instance_expr, set, set_arguments, loc, false, prepared);
8575
8576                         if (temp != null)
8577                                 temp.Emit (ec);
8578                 }
8579
8580
8581                 public override void Emit (EmitContext ec)
8582                 {
8583                         Emit (ec, false);
8584                 }
8585         }
8586
8587         /// <summary>
8588         ///   The base operator for method names
8589         /// </summary>
8590         public class BaseAccess : Expression {
8591                 string member;
8592
8593                 public BaseAccess (string member, Location l)
8594                 {
8595                         this.member = member;
8596                         loc = l;
8597                 }
8598
8599                 public override Expression DoResolve (EmitContext ec)
8600                 {
8601                         Expression c = CommonResolve (ec);
8602
8603                         if (c == null)
8604                                 return null;
8605
8606                         //
8607                         // MethodGroups use this opportunity to flag an error on lacking ()
8608                         //
8609                         if (!(c is MethodGroupExpr))
8610                                 return c.Resolve (ec);
8611                         return c;
8612                 }
8613
8614                 public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
8615                 {
8616                         Expression c = CommonResolve (ec);
8617
8618                         if (c == null)
8619                                 return null;
8620
8621                         //
8622                         // MethodGroups use this opportunity to flag an error on lacking ()
8623                         //
8624                         if (! (c is MethodGroupExpr))
8625                                 return c.DoResolveLValue (ec, right_side);
8626
8627                         return c;
8628                 }
8629
8630                 Expression CommonResolve (EmitContext ec)
8631                 {
8632                         Expression member_lookup;
8633                         Type current_type = ec.ContainerType;
8634                         Type base_type = current_type.BaseType;
8635                         Expression e;
8636
8637                         if (ec.IsStatic){
8638                                 Error (1511, "Keyword base is not allowed in static method");
8639                                 return null;
8640                         }
8641
8642                         if (ec.IsFieldInitializer){
8643                                 Error (1512, "Keyword base is not available in the current context");
8644                                 return null;
8645                         }
8646
8647                         member_lookup = MemberLookup (ec, ec.ContainerType, null, base_type,
8648                                                       member, AllMemberTypes, AllBindingFlags,
8649                                                       loc);
8650                         if (member_lookup == null) {
8651                                 MemberLookupFailed (
8652                                         ec, base_type, base_type, member, null, loc);
8653                                 return null;
8654                         }
8655
8656                         Expression left;
8657
8658                         if (ec.IsStatic)
8659                                 left = new TypeExpression (base_type, loc);
8660                         else
8661                                 left = ec.GetThis (loc);
8662
8663                         e = MemberAccess.ResolveMemberAccess (ec, member_lookup, left, loc, null);
8664
8665                         if (e is PropertyExpr){
8666                                 PropertyExpr pe = (PropertyExpr) e;
8667
8668                                 pe.IsBase = true;
8669                         }
8670
8671                         if (e is MethodGroupExpr)
8672                                 ((MethodGroupExpr) e).IsBase = true;
8673
8674                         return e;
8675                 }
8676
8677                 public override void Emit (EmitContext ec)
8678                 {
8679                         throw new Exception ("Should never be called");
8680                 }
8681         }
8682
8683         /// <summary>
8684         ///   The base indexer operator
8685         /// </summary>
8686         public class BaseIndexerAccess : IndexerAccess {
8687                 public BaseIndexerAccess (ArrayList args, Location loc)
8688                         : base (null, true, loc)
8689                 {
8690                         arguments = new ArrayList ();
8691                         foreach (Expression tmp in args)
8692                                 arguments.Add (new Argument (tmp, Argument.AType.Expression));
8693                 }
8694
8695                 protected override bool CommonResolve (EmitContext ec)
8696                 {
8697                         instance_expr = ec.GetThis (loc);
8698
8699                         current_type = ec.ContainerType.BaseType;
8700                         indexer_type = current_type;
8701
8702                         foreach (Argument a in arguments){
8703                                 if (!a.Resolve (ec, loc))
8704                                         return false;
8705                         }
8706
8707                         return true;
8708                 }
8709         }
8710
8711         /// <summary>
8712         ///   This class exists solely to pass the Type around and to be a dummy
8713         ///   that can be passed to the conversion functions (this is used by
8714         ///   foreach implementation to typecast the object return value from
8715         ///   get_Current into the proper type.  All code has been generated and
8716         ///   we only care about the side effect conversions to be performed
8717         ///
8718         ///   This is also now used as a placeholder where a no-action expression
8719         ///   is needed (the `New' class).
8720         /// </summary>
8721         public class EmptyExpression : Expression {
8722                 public static readonly EmptyExpression Null = new EmptyExpression ();
8723
8724                 // TODO: should be protected
8725                 public EmptyExpression ()
8726                 {
8727                         type = TypeManager.object_type;
8728                         eclass = ExprClass.Value;
8729                         loc = Location.Null;
8730                 }
8731
8732                 public EmptyExpression (Type t)
8733                 {
8734                         type = t;
8735                         eclass = ExprClass.Value;
8736                         loc = Location.Null;
8737                 }
8738
8739                 public override Expression DoResolve (EmitContext ec)
8740                 {
8741                         return this;
8742                 }
8743
8744                 public override void Emit (EmitContext ec)
8745                 {
8746                         // nothing, as we only exist to not do anything.
8747                 }
8748
8749                 //
8750                 // This is just because we might want to reuse this bad boy
8751                 // instead of creating gazillions of EmptyExpressions.
8752                 // (CanImplicitConversion uses it)
8753                 //
8754                 public void SetType (Type t)
8755                 {
8756                         type = t;
8757                 }
8758         }
8759
8760         public class UserCast : Expression {
8761                 MethodBase method;
8762                 Expression source;
8763
8764                 public UserCast (MethodInfo method, Expression source, Location l)
8765                 {
8766                         this.method = method;
8767                         this.source = source;
8768                         type = method.ReturnType;
8769                         eclass = ExprClass.Value;
8770                         loc = l;
8771                 }
8772
8773                 public Expression Source {
8774                         get {
8775                                 return source;
8776                         }
8777                 }
8778
8779                 public override Expression DoResolve (EmitContext ec)
8780                 {
8781                         //
8782                         // We are born fully resolved
8783                         //
8784                         return this;
8785                 }
8786
8787                 public override void Emit (EmitContext ec)
8788                 {
8789                         ILGenerator ig = ec.ig;
8790
8791                         source.Emit (ec);
8792
8793                         if (method is MethodInfo)
8794                                 ig.Emit (OpCodes.Call, (MethodInfo) method);
8795                         else
8796                                 ig.Emit (OpCodes.Call, (ConstructorInfo) method);
8797
8798                 }
8799         }
8800
8801         // <summary>
8802         //   This class is used to "construct" the type during a typecast
8803         //   operation.  Since the Type.GetType class in .NET can parse
8804         //   the type specification, we just use this to construct the type
8805         //   one bit at a time.
8806         // </summary>
8807         public class ComposedCast : TypeExpr {
8808                 Expression left;
8809                 string dim;
8810
8811                 public ComposedCast (Expression left, string dim, Location l)
8812                 {
8813                         this.left = left;
8814                         this.dim = dim;
8815                         loc = l;
8816                 }
8817
8818                 protected override TypeExpr DoResolveAsTypeStep (EmitContext ec)
8819                 {
8820                         TypeExpr lexpr = left.ResolveAsTypeTerminal (ec);
8821                         if (lexpr == null)
8822                                 return null;
8823
8824                         Type ltype = lexpr.Type;
8825
8826                         if ((ltype == TypeManager.void_type) && (dim != "*")) {
8827                                 Report.Error (1547, Location,
8828                                               "Keyword 'void' cannot be used in this context");
8829                                 return null;
8830                         }
8831
8832                         if ((dim.Length > 0) && (dim [0] == '?')) {
8833                                 TypeExpr nullable = new NullableType (left, loc);
8834                                 if (dim.Length > 1)
8835                                         nullable = new ComposedCast (nullable, dim.Substring (1), loc);
8836                                 return nullable.ResolveAsTypeTerminal (ec);
8837                         }
8838
8839                         int pos = 0;
8840                         while ((pos < dim.Length) && (dim [pos] == '[')) {
8841                                 pos++;
8842
8843                                 if (dim [pos] == ']') {
8844                                         ltype = ltype.MakeArrayType ();
8845                                         pos++;
8846
8847                                         if (pos < dim.Length)
8848                                                 continue;
8849
8850                                         type = ltype;
8851                                         eclass = ExprClass.Type;
8852                                         return this;
8853                                 }
8854
8855                                 int rank = 0;
8856                                 while (dim [pos] == ',') {
8857                                         pos++; rank++;
8858                                 }
8859
8860                                 if ((dim [pos] != ']') || (pos != dim.Length-1))
8861                                         return null;
8862
8863                                 type = ltype.MakeArrayType (rank + 1);
8864                                 eclass = ExprClass.Type;
8865                                 return this;
8866                         }
8867
8868                         if (dim != "") {
8869                                 //
8870                                 // ltype.Fullname is already fully qualified, so we can skip
8871                                 // a lot of probes, and go directly to TypeManager.LookupType
8872                                 //
8873                                 string fname = ltype.FullName != null ? ltype.FullName : ltype.Name;
8874                                 string cname = fname + dim;
8875                                 type = TypeManager.LookupTypeDirect (cname);
8876                                 if (type == null){
8877                                         //
8878                                         // For arrays of enumerations we are having a problem
8879                                         // with the direct lookup.  Need to investigate.
8880                                         //
8881                                         // For now, fall back to the full lookup in that case.
8882                                         //
8883                                         FullNamedExpression e = ec.DeclSpace.LookupType (cname, false, loc);
8884                                         if (e is TypeExpr)
8885                                                 type = ((TypeExpr) e).ResolveType (ec);
8886                                         if (type == null)
8887                                                 return null;
8888                                 }
8889                         } else {
8890                                 type = ltype;
8891                         }
8892
8893                         if (!ec.InUnsafe && type.IsPointer){
8894                                 UnsafeError (loc);
8895                                 return null;
8896                         }
8897
8898                         if (type.IsArray && (type.GetElementType () == TypeManager.arg_iterator_type ||
8899                                 type.GetElementType () == TypeManager.typed_reference_type)) {
8900                                 Report.Error (611, loc, "Array elements cannot be of type '{0}'", TypeManager.CSharpName (type.GetElementType ()));
8901                                 return null;
8902                         }
8903
8904                         eclass = ExprClass.Type;
8905                         return this;
8906                 }
8907
8908                 public override string Name {
8909                         get {
8910                                 return left + dim;
8911                         }
8912                 }
8913
8914                 public override string FullName {
8915                         get {
8916                                 return type.FullName;
8917                         }
8918                 }
8919         }
8920
8921         //
8922         // This class is used to represent the address of an array, used
8923         // only by the Fixed statement, this is like the C "&a [0]" construct.
8924         //
8925         public class ArrayPtr : Expression {
8926                 Expression array;
8927
8928                 public ArrayPtr (Expression array, Location l)
8929                 {
8930                         Type array_type = TypeManager.GetElementType (array.Type);
8931
8932                         this.array = array;
8933
8934                         type = TypeManager.GetPointerType (array_type);
8935                         eclass = ExprClass.Value;
8936                         loc = l;
8937                 }
8938
8939                 public override void Emit (EmitContext ec)
8940                 {
8941                         ILGenerator ig = ec.ig;
8942
8943                         array.Emit (ec);
8944                         IntLiteral.EmitInt (ig, 0);
8945                         ig.Emit (OpCodes.Ldelema, TypeManager.GetElementType (array.Type));
8946                 }
8947
8948                 public override Expression DoResolve (EmitContext ec)
8949                 {
8950                         //
8951                         // We are born fully resolved
8952                         //
8953                         return this;
8954                 }
8955         }
8956
8957         //
8958         // Used by the fixed statement
8959         //
8960         public class StringPtr : Expression {
8961                 LocalBuilder b;
8962
8963                 public StringPtr (LocalBuilder b, Location l)
8964                 {
8965                         this.b = b;
8966                         eclass = ExprClass.Value;
8967                         type = TypeManager.char_ptr_type;
8968                         loc = l;
8969                 }
8970
8971                 public override Expression DoResolve (EmitContext ec)
8972                 {
8973                         // This should never be invoked, we are born in fully
8974                         // initialized state.
8975
8976                         return this;
8977                 }
8978
8979                 public override void Emit (EmitContext ec)
8980                 {
8981                         ILGenerator ig = ec.ig;
8982
8983                         ig.Emit (OpCodes.Ldloc, b);
8984                         ig.Emit (OpCodes.Conv_I);
8985                         ig.Emit (OpCodes.Call, TypeManager.int_get_offset_to_string_data);
8986                         ig.Emit (OpCodes.Add);
8987                 }
8988         }
8989
8990         //
8991         // Implements the `stackalloc' keyword
8992         //
8993         public class StackAlloc : Expression {
8994                 Type otype;
8995                 Expression t;
8996                 Expression count;
8997
8998                 public StackAlloc (Expression type, Expression count, Location l)
8999                 {
9000                         t = type;
9001                         this.count = count;
9002                         loc = l;
9003                 }
9004
9005                 public override Expression DoResolve (EmitContext ec)
9006                 {
9007                         count = count.Resolve (ec);
9008                         if (count == null)
9009                                 return null;
9010
9011                         if (count.Type != TypeManager.int32_type){
9012                                 count = Convert.ImplicitConversionRequired (ec, count, TypeManager.int32_type, loc);
9013                                 if (count == null)
9014                                         return null;
9015                         }
9016
9017                         Constant c = count as Constant;
9018                         if (c != null && c.IsNegative) {
9019                                 Report.Error (247, loc, "Cannot use a negative size with stackalloc");
9020                                 return null;
9021                         }
9022
9023                         if (ec.CurrentBranching.InCatch () ||
9024                             ec.CurrentBranching.InFinally (true)) {
9025                                 Error (255,
9026                                               "stackalloc can not be used in a catch or finally block");
9027                                 return null;
9028                         }
9029
9030                         TypeExpr texpr = t.ResolveAsTypeTerminal (ec);
9031                         if (texpr == null)
9032                                 return null;
9033
9034                         otype = texpr.Type;
9035
9036                         if (!TypeManager.VerifyUnManaged (otype, loc))
9037                                 return null;
9038
9039                         type = TypeManager.GetPointerType (otype);
9040                         eclass = ExprClass.Value;
9041
9042                         return this;
9043                 }
9044
9045                 public override void Emit (EmitContext ec)
9046                 {
9047                         int size = GetTypeSize (otype);
9048                         ILGenerator ig = ec.ig;
9049
9050                         if (size == 0)
9051                                 ig.Emit (OpCodes.Sizeof, otype);
9052                         else
9053                                 IntConstant.EmitInt (ig, size);
9054                         count.Emit (ec);
9055                         ig.Emit (OpCodes.Mul);
9056                         ig.Emit (OpCodes.Localloc);
9057                 }
9058         }
9059 }