mcs/gmcs/decl.cs

   1 //
   2 // decl.cs: Declaration base class for structs, classes, enums and interfaces.
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //
   6 // Licensed under the terms of the GNU GPL
   7 //
   8 // (C) 2001 Ximian, Inc (http://www.ximian.com)
   9 //
  10 // TODO: Move the method verification stuff from the class.cs and interface.cs here
  11 //
  12
  13 using System;
  14 using System.Collections;
  15 using System.Reflection.Emit;
  16 using System.Reflection;
  17
  18 namespace Mono.CSharp {
  19
  20         /// <summary>
  21         ///   Base representation for members.  This is only used to keep track
  22         ///   of Name, Location and Modifier flags.
  23         /// </summary>
  24         public abstract class MemberCore {
  25                 /// <summary>
  26                 ///   Public name
  27                 /// </summary>
  28                 public string Name;
  29
  30                 /// <summary>
  31                 ///   Modifier flags that the user specified in the source code
  32                 /// </summary>
  33                 public int ModFlags;
  34
  35                 /// <summary>
  36                 ///   Location where this declaration happens
  37                 /// </summary>
  38                 public readonly Location Location;
  39
  40                 public MemberCore (string name, Location loc)
  41                 {
  42                         Name = name;
  43                         Location = loc;
  44                 }
  45
  46                 public abstract bool Define (TypeContainer parent);
  47
  48                 //
  49                 // Whehter is it ok to use an unsafe pointer in this type container
  50                 //
  51                 public bool UnsafeOK (DeclSpace parent)
  52                 {
  53                         //
  54                         // First check if this MemberCore modifier flags has unsafe set
  55                         //
  56                         if ((ModFlags & Modifiers.UNSAFE) != 0)
  57                                 return true;
  58
  59                         if (parent.UnsafeContext)
  60                                 return true;
  61
  62                         Expression.UnsafeError (Location);
  63                         return false;
  64                 }
  65         }
  66
  67         /// <summary>
  68         ///   Base class for structs, classes, enumerations and interfaces.
  69         /// </summary>
  70         /// <remarks>
  71         ///   They all create new declaration spaces.  This
  72         ///   provides the common foundation for managing those name
  73         ///   spaces.
  74         /// </remarks>
  75         public abstract class DeclSpace : MemberCore {
  76                 /// <summary>
  77                 ///   this points to the actual definition that is being
  78                 ///   created with System.Reflection.Emit
  79                 /// </summary>
  80                 public TypeBuilder TypeBuilder;
  81
  82                 /// <summary>
  83                 ///   This variable tracks whether we have Closed the type
  84                 /// </summary>
  85                 public bool Created = false;
  86
  87                 //
  88                 // This is the namespace in which this typecontainer
  89                 // was declared.  We use this to resolve names.
  90                 //
  91                 public NamespaceEntry NamespaceEntry;
  92
  93                 public Hashtable Cache = new Hashtable ();
  94
  95                 public string Basename;
  96
  97                 /// <summary>
  98                 ///   defined_names is used for toplevel objects
  99                 /// </summary>
 100                 protected Hashtable defined_names;
 101
 102                 //
 103                 // Whether we are Generic
 104                 //
 105                 public bool IsGeneric;
 106
 107                 TypeContainer parent;
 108
 109                 public DeclSpace (NamespaceEntry ns, TypeContainer parent, string name, Location l)
 110                         : base (name, l)
 111                 {
 112                         NamespaceEntry = ns;
 113                         Basename = name.Substring (1 + name.LastIndexOf ('.'));
 114                         defined_names = new Hashtable ();
 115                         this.parent = parent;
 116                 }
 117
 118                 public void RecordDecl ()
 119                 {
 120                         if ((NamespaceEntry != null) && (parent == RootContext.Tree.Types))
 121                                 NamespaceEntry.DefineName (Basename, this);
 122                 }
 123
 124                 /// <summary>
 125                 ///   The result value from adding an declaration into
 126                 ///   a struct or a class
 127                 /// </summary>
 128                 public enum AdditionResult {
 129                         /// <summary>
 130                         /// The declaration has been successfully
 131                         /// added to the declation space.
 132                         /// </summary>
 133                         Success,
 134
 135                         /// <summary>
 136                         ///   The symbol has already been defined.
 137                         /// </summary>
 138                         NameExists,
 139
 140                         /// <summary>
 141                         ///   Returned if the declation being added to the
 142                         ///   name space clashes with its container name.
 143                         ///
 144                         ///   The only exceptions for this are constructors
 145                         ///   and static constructors
 146                         /// </summary>
 147                         EnclosingClash,
 148
 149                         /// <summary>
 150                         ///   Returned if a constructor was created (because syntactically
 151                         ///   it looked like a constructor) but was not (because the name
 152                         ///   of the method is not the same as the container class
 153                         /// </summary>
 154                         NotAConstructor,
 155
 156                         /// <summary>
 157                         ///   This is only used by static constructors to emit the
 158                         ///   error 111, but this error for other things really
 159                         ///   happens at another level for other functions.
 160                         /// </summary>
 161                         MethodExists,
 162
 163                         /// <summary>
 164                         ///   Some other error.
 165                         /// </summary>
 166                         Error
 167                 }
 168
 169                 /// <summary>
 170                 ///   Returns a status code based purely on the name
 171                 ///   of the member being added
 172                 /// </summary>
 173                 protected AdditionResult IsValid (string basename, string name)
 174                 {
 175                         if (basename == Basename)
 176                                 return AdditionResult.EnclosingClash;
 177
 178                         if (defined_names.Contains (name))
 179                                 return AdditionResult.NameExists;
 180
 181                         return AdditionResult.Success;
 182                 }
 183
 184                 public static int length;
 185                 public static int small;
 186
 187                 /// <summary>
 188                 ///   Introduce @name into this declaration space and
 189                 ///   associates it with the object @o.  Note that for
 190                 ///   methods this will just point to the first method. o
 191                 /// </summary>
 192                 protected void DefineName (string name, object o)
 193                 {
 194                         defined_names.Add (name, o);
 195
 196 #if DEBUGME
 197                         int p = name.LastIndexOf (".");
 198                         int l = name.Length;
 199                         length += l;
 200                         small += l -p;
 201 #endif
 202                 }
 203
 204                 /// <summary>
 205                 ///   Returns the object associated with a given name in the declaration
 206                 ///   space.  This is the inverse operation of `DefineName'
 207                 /// </summary>
 208                 public object GetDefinition (string name)
 209                 {
 210                         return defined_names [name];
 211                 }
 212
 213                 bool in_transit = false;
 214
 215                 /// <summary>
 216                 ///   This function is used to catch recursive definitions
 217                 ///   in declarations.
 218                 /// </summary>
 219                 public bool InTransit {
 220                         get {
 221                                 return in_transit;
 222                         }
 223
 224                         set {
 225                                 in_transit = value;
 226                         }
 227                 }
 228
 229                 public TypeContainer Parent {
 230                         get {
 231                                 return parent;
 232                         }
 233                 }
 234
 235                 /// <summary>
 236                 ///   Looks up the alias for the name
 237                 /// </summary>
 238                 public string LookupAlias (string name)
 239                 {
 240                         if (NamespaceEntry != null)
 241                                 return NamespaceEntry.LookupAlias (name);
 242                         else
 243                                 return null;
 244                 }
 245
 246                 //
 247                 // root_types contains all the types.  All TopLevel types
 248                 // hence have a parent that points to `root_types', that is
 249                 // why there is a non-obvious test down here.
 250                 //
 251                 public bool IsTopLevel {
 252                         get {
 253                                 if (parent != null){
 254                                         if (parent.parent == null)
 255                                                 return true;
 256                                 }
 257                                 return false;
 258                         }
 259                 }
 260
 261                 public virtual void CloseType ()
 262                 {
 263                         if (!Created){
 264                                 try {
 265                                         TypeBuilder.CreateType ();
 266                                 } catch {
 267                                         //
 268                                         // The try/catch is needed because
 269                                         // nested enumerations fail to load when they
 270                                         // are defined.
 271                                         //
 272                                         // Even if this is the right order (enumerations
 273                                         // declared after types).
 274                                         //
 275                                         // Note that this still creates the type and
 276                                         // it is possible to save it
 277                                 }
 278                                 Created = true;
 279                         }
 280                 }
 281
 282                 /// <remarks>
 283                 ///  Should be overriten by the appropriate declaration space
 284                 /// </remarks>
 285                 public abstract TypeBuilder DefineType ();
 286
 287                 /// <summary>
 288                 ///   Define all members, but don't apply any attributes or do anything which may
 289                 ///   access not-yet-defined classes.  This method also creates the MemberCache.
 290                 /// </summary>
 291                 public abstract bool DefineMembers (TypeContainer parent);
 292
 293                 //
 294                 // Whether this is an `unsafe context'
 295                 //
 296                 public bool UnsafeContext {
 297                         get {
 298                                 if ((ModFlags & Modifiers.UNSAFE) != 0)
 299                                         return true;
 300                                 if (parent != null)
 301                                         return parent.UnsafeContext;
 302                                 return false;
 303                         }
 304                 }
 305
 306                 public static string MakeFQN (string nsn, string name)
 307                 {
 308                         if (nsn == "")
 309                                 return name;
 310                         return String.Concat (nsn, ".", name);
 311                 }
 312
 313                 EmitContext type_resolve_ec;
 314                 EmitContext GetTypeResolveEmitContext (TypeContainer parent, Location loc)
 315                 {
 316                         type_resolve_ec = new EmitContext (parent, this, loc, null, null, ModFlags, false);
 317                         type_resolve_ec.ResolvingTypeTree = true;
 318
 319                         return type_resolve_ec;
 320                 }
 321
 322                 // <summary>
 323                 //    Looks up the type, as parsed into the expression `e'
 324                 // </summary>
 325                 public Type ResolveType (Expression e, bool silent, Location loc)
 326                 {
 327                         if (type_resolve_ec == null)
 328                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 329                         type_resolve_ec.loc = loc;
 330                         type_resolve_ec.ContainerType = TypeBuilder;
 331
 332                         int errors = Report.Errors;
 333                         Expression d = e.ResolveAsTypeTerminal (type_resolve_ec);
 334
 335                         if (d == null || d.eclass != ExprClass.Type){
 336                                 if (!silent && errors == Report.Errors){
 337                                         Console.WriteLine ("Type is: " + e.GetType().ToString ());
 338                                         Report.Error (246, loc, "Cannot find type `"+ e.ToString () +"'");
 339                                 }
 340                                 return null;
 341                         }
 342
 343                         if (d is ConstructedType)
 344                                 ((ConstructedType) d).ResolveType (type_resolve_ec);
 345
 346                         if (!CheckAccessLevel (d.Type)) {
 347                                 Report. Error (122, loc,  "`" + d.Type + "' " +
 348                                        "is inaccessible because of its protection level");
 349                                 return null;
 350                         }
 351
 352                         return d.Type;
 353                 }
 354
 355                 // <summary>
 356                 //    Resolves the expression `e' for a type, and will recursively define
 357                 //    types.
 358                 // </summary>
 359                 public Expression ResolveTypeExpr (Expression e, bool silent, Location loc)
 360                 {
 361                         if (type_resolve_ec == null)
 362                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 363                         type_resolve_ec.loc = loc;
 364                         type_resolve_ec.ContainerType = TypeBuilder;
 365
 366                         Expression d = e.ResolveAsTypeTerminal (type_resolve_ec);
 367
 368                         if (d == null || d.eclass != ExprClass.Type){
 369                                 if (!silent){
 370                                         Report.Error (246, loc, "Cannot find type `"+ e +"'");
 371                                 }
 372                                 return null;
 373                         }
 374
 375                         return d;
 376                 }
 377
 378                 public bool CheckAccessLevel (Type check_type)
 379                 {
 380                         if (check_type == TypeBuilder)
 381                                 return true;
 382
 383                         if (check_type.IsGenericParameter)
 384                                 return true; // FIXME
 385
 386                         TypeAttributes check_attr = check_type.Attributes & TypeAttributes.VisibilityMask;
 387
 388                         //
 389                         // Broken Microsoft runtime, return public for arrays, no matter what
 390                         // the accessibility is for their underlying class, and they return
 391                         // NonPublic visibility for pointers
 392                         //
 393                         if (check_type.IsArray || check_type.IsPointer)
 394                                 return CheckAccessLevel (TypeManager.GetElementType (check_type));
 395
 396                         switch (check_attr){
 397                         case TypeAttributes.Public:
 398                                 return true;
 399
 400                         case TypeAttributes.NotPublic:
 401                                 //
 402                                 // This test should probably use the declaringtype.
 403                                 //
 404                                 if (check_type.Assembly == TypeBuilder.Assembly){
 405                                         return true;
 406                                 }
 407                                 return false;
 408
 409                         case TypeAttributes.NestedPublic:
 410                                 return true;
 411
 412                         case TypeAttributes.NestedPrivate:
 413                                 string check_type_name = check_type.FullName;
 414                                 string type_name = TypeBuilder.FullName;
 415
 416                                 int cio = check_type_name.LastIndexOf ("+");
 417                                 string container = check_type_name.Substring (0, cio);
 418
 419                                 //
 420                                 // Check if the check_type is a nested class of the current type
 421                                 //
 422                                 if (check_type_name.StartsWith (type_name + "+")){
 423                                         return true;
 424                                 }
 425
 426                                 if (type_name.StartsWith (container)){
 427                                         return true;
 428                                 }
 429
 430                                 return false;
 431
 432                         case TypeAttributes.NestedFamily:
 433                                 //
 434                                 // Only accessible to methods in current type or any subtypes
 435                                 //
 436                                 return FamilyAccessible (check_type);
 437
 438                         case TypeAttributes.NestedFamANDAssem:
 439                                 return (check_type.Assembly == TypeBuilder.Assembly) &&
 440                                         FamilyAccessible (check_type);
 441
 442                         case TypeAttributes.NestedFamORAssem:
 443                                 return (check_type.Assembly == TypeBuilder.Assembly) ||
 444                                         FamilyAccessible (check_type);
 445
 446                         case TypeAttributes.NestedAssembly:
 447                                 return check_type.Assembly == TypeBuilder.Assembly;
 448                         }
 449
 450                         Console.WriteLine ("HERE: " + check_attr);
 451                         return false;
 452
 453                 }
 454
 455                 protected bool FamilyAccessible (Type check_type)
 456                 {
 457                         Type declaring = check_type.DeclaringType;
 458                         if (TypeBuilder.IsSubclassOf (declaring))
 459                                 return true;
 460
 461                         string check_type_name = check_type.FullName;
 462                         string type_name = TypeBuilder.FullName;
 463
 464                         int cio = check_type_name.LastIndexOf ("+");
 465                         string container = check_type_name.Substring (0, cio);
 466
 467                         //
 468                         // Check if the check_type is a nested class of the current type
 469                         //
 470                         if (check_type_name.StartsWith (container + "+"))
 471                                 return true;
 472
 473                         return false;
 474                 }
 475
 476                 // Access level of a type.
 477                 enum AccessLevel {
 478                         Public                  = 0,
 479                         ProtectedInternal       = 1,
 480                         Internal                = 2,
 481                         Protected               = 3,
 482                         Private                 = 4
 483                 }
 484
 485                 // Check whether `flags' denotes a more restricted access than `level'
 486                 // and return the new level.
 487                 static AccessLevel CheckAccessLevel (AccessLevel level, int flags)
 488                 {
 489                         AccessLevel old_level = level;
 490
 491                         if ((flags & Modifiers.INTERNAL) != 0) {
 492                                 if ((flags & Modifiers.PROTECTED) != 0) {
 493                                         if ((int) level < (int) AccessLevel.ProtectedInternal)
 494                                                 level = AccessLevel.ProtectedInternal;
 495                                 } else {
 496                                         if ((int) level < (int) AccessLevel.Internal)
 497                                                 level = AccessLevel.Internal;
 498                                 }
 499                         } else if ((flags & Modifiers.PROTECTED) != 0) {
 500                                 if ((int) level < (int) AccessLevel.Protected)
 501                                         level = AccessLevel.Protected;
 502                         } else if ((flags & Modifiers.PRIVATE) != 0)
 503                                 level = AccessLevel.Private;
 504
 505                         return level;
 506                 }
 507
 508                 // Return the access level for a new member which is defined in the current
 509                 // TypeContainer with access modifiers `flags'.
 510                 AccessLevel GetAccessLevel (int flags)
 511                 {
 512                         if ((flags & Modifiers.PRIVATE) != 0)
 513                                 return AccessLevel.Private;
 514
 515                         AccessLevel level;
 516                         if (!IsTopLevel && (Parent != null))
 517                                 level = Parent.GetAccessLevel (flags);
 518                         else
 519                                 level = AccessLevel.Public;
 520
 521                         return CheckAccessLevel (CheckAccessLevel (level, flags), ModFlags);
 522                 }
 523
 524                 // Return the access level for type `t', but don't give more access than `flags'.
 525                 static AccessLevel GetAccessLevel (Type t, int flags)
 526                 {
 527                         if (((flags & Modifiers.PRIVATE) != 0) || t.IsNestedPrivate)
 528                                 return AccessLevel.Private;
 529
 530                         AccessLevel level;
 531                         if (TypeManager.IsBuiltinType (t))
 532                                 return AccessLevel.Public;
 533                         else if ((t.DeclaringType != null) && (t != t.DeclaringType))
 534                                 level = GetAccessLevel (t.DeclaringType, flags);
 535                         else {
 536                                 level = CheckAccessLevel (AccessLevel.Public, flags);
 537                         }
 538
 539                         if (t.IsNestedPublic)
 540                                 return level;
 541
 542                         if (t.IsNestedAssembly || t.IsNotPublic) {
 543                                 if ((int) level < (int) AccessLevel.Internal)
 544                                         level = AccessLevel.Internal;
 545                         }
 546
 547                         if (t.IsNestedFamily) {
 548                                 if ((int) level < (int) AccessLevel.Protected)
 549                                         level = AccessLevel.Protected;
 550                         }
 551
 552                         if (t.IsNestedFamORAssem) {
 553                                 if ((int) level < (int) AccessLevel.ProtectedInternal)
 554                                         level = AccessLevel.ProtectedInternal;
 555                         }
 556
 557                         return level;
 558                 }
 559
 560                 //
 561                 // Returns true if `parent' is as accessible as the flags `flags'
 562                 // given for this member.
 563                 //
 564                 public bool AsAccessible (Type parent, int flags)
 565                 {
 566                         if (parent.IsGenericParameter)
 567                                 return true; // FIXME
 568
 569                         while (parent.IsArray || parent.IsPointer || parent.IsByRef)
 570                                 parent = TypeManager.GetElementType (parent);
 571
 572                         AccessLevel level = GetAccessLevel (flags);
 573                         AccessLevel level2 = GetAccessLevel (parent, flags);
 574
 575                         return (int) level >= (int) level2;
 576                 }
 577
 578                 static DoubleHash dh = new DoubleHash ();
 579
 580                 Type LookupInterfaceOrClass (string ns, string name, out bool error)
 581                 {
 582                         DeclSpace parent;
 583                         Type t;
 584                         object r;
 585
 586                         error = false;
 587
 588                         if (dh.Lookup (ns, name, out r))
 589                                 t = (Type) r;
 590                         else {
 591                                 if (ns != ""){
 592                                         if (Namespace.IsNamespace (ns)){
 593                                                 string fullname = (ns != "") ? ns + "." + name : name;
 594                                                 t = TypeManager.LookupType (fullname);
 595                                         } else
 596                                                 t = null;
 597                                 } else
 598                                         t = TypeManager.LookupType (name);
 599                         }
 600
 601                         if (t != null)
 602                                 return t;
 603
 604                         //
 605                         // In case we are fed a composite name, normalize it.
 606                         //
 607                         int p = name.LastIndexOf ('.');
 608                         if (p != -1){
 609                                 ns = MakeFQN (ns, name.Substring (0, p));
 610                                 name = name.Substring (p+1);
 611                         }
 612
 613                         parent = RootContext.Tree.LookupByNamespace (ns, name);
 614                         if (parent == null)
 615                                 return null;
 616
 617                         t = parent.DefineType ();
 618                         dh.Insert (ns, name, t);
 619                         if (t == null){
 620                                 error = true;
 621                                 return null;
 622                         }
 623                         return t;
 624                 }
 625
 626                 public static void Error_AmbiguousTypeReference (Location loc, string name, Type t1, Type t2)
 627                 {
 628                         Report.Error (104, loc,
 629                                       String.Format ("`{0}' is an ambiguous reference ({1} or {2}) ", name,
 630                                                      t1.FullName, t2.FullName));
 631                 }
 632
 633                 /// <summary>
 634                 ///   GetType is used to resolve type names at the DeclSpace level.
 635                 ///   Use this to lookup class/struct bases, interface bases or
 636                 ///   delegate type references
 637                 /// </summary>
 638                 ///
 639                 /// <remarks>
 640                 ///   Contrast this to LookupType which is used inside method bodies to
 641                 ///   lookup types that have already been defined.  GetType is used
 642                 ///   during the tree resolution process and potentially define
 643                 ///   recursively the type
 644                 /// </remarks>
 645                 public Type FindType (Location loc, string name)
 646                 {
 647                         Type t;
 648                         bool error;
 649
 650                         //
 651                         // For the case the type we are looking for is nested within this one
 652                         // or is in any base class
 653                         //
 654                         DeclSpace containing_ds = this;
 655
 656                         while (containing_ds != null){
 657                                 Type container_type = containing_ds.TypeBuilder;
 658                                 Type current_type = container_type;
 659
 660                                 while (current_type != null) {
 661                                         string pre = current_type.FullName;
 662
 663                                         t = LookupInterfaceOrClass (pre, name, out error);
 664                                         if (error)
 665                                                 return null;
 666
 667                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
 668                                                 return t;
 669
 670                                         current_type = current_type.BaseType;
 671                                 }
 672                                 containing_ds = containing_ds.Parent;
 673                         }
 674
 675                         //
 676                         // Attempt to lookup the class on our namespace and all it's implicit parents
 677                         //
 678                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.ImplicitParent) {
 679                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 680                                 if (error)
 681                                         return null;
 682
 683                                 if (t != null)
 684                                         return t;
 685                         }
 686
 687                         //
 688                         // Attempt to do a direct unqualified lookup
 689                         //
 690                         t = LookupInterfaceOrClass ("", name, out error);
 691                         if (error)
 692                                 return null;
 693
 694                         if (t != null)
 695                                 return t;
 696
 697                         //
 698                         // Attempt to lookup the class on any of the `using'
 699                         // namespaces
 700                         //
 701
 702                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.Parent){
 703
 704                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 705                                 if (error)
 706                                         return null;
 707
 708                                 if (t != null)
 709                                         return t;
 710
 711                                 //
 712                                 // Now check the using clause list
 713                                 //
 714                                 Type match = null;
 715                                 foreach (Namespace using_ns in ns.GetUsingTable ()) {
 716                                         match = LookupInterfaceOrClass (using_ns.Name, name, out error);
 717                                         if (error)
 718                                                 return null;
 719
 720                                         if (match != null){
 721                                                 if (t != null){
 722                                                         if (CheckAccessLevel (match)) {
 723                                                                 Error_AmbiguousTypeReference (loc, name, t, match);
 724                                                                 return null;
 725                                                         }
 726                                                         continue;
 727                                                 }
 728
 729                                                 t = match;
 730                                         }
 731                                 }
 732                                 if (t != null)
 733                                         return t;
 734                         }
 735
 736                         //Report.Error (246, Location, "Can not find type `"+name+"'");
 737                         return null;
 738                 }
 739
 740                 /// <remarks>
 741                 ///   This function is broken and not what you're looking for.  It should only
 742                 ///   be used while the type is still being created since it doesn't use the cache
 743                 ///   and relies on the filter doing the member name check.
 744                 /// </remarks>
 745                 public abstract MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 746                                                         MemberFilter filter, object criteria);
 747
 748                 /// <remarks>
 749                 ///   If we have a MemberCache, return it.  This property may return null if the
 750                 ///   class doesn't have a member cache or while it's still being created.
 751                 /// </remarks>
 752                 public abstract MemberCache MemberCache {
 753                         get;
 754                 }
 755
 756                 //
 757                 // Extensions for generics
 758                 //
 759                 TypeParameter[] type_params;
 760
 761                 ///
 762                 /// Called by the parser to configure the type_parameter_list for this
 763                 /// declaration space
 764                 ///
 765                 public AdditionResult SetParameterInfo (ArrayList type_parameter_list, ArrayList constraints_list)
 766                 {
 767                         type_params = new TypeParameter [type_parameter_list.Count];
 768
 769                         //
 770                         // Mark this type as Generic
 771                         //
 772                         IsGeneric = true;
 773
 774                         //
 775                         // Register all the names
 776                         //
 777                         for (int i = 0; i < type_parameter_list.Count; i++) {
 778                                 string name = (string) type_parameter_list [i];
 779
 780                                 AdditionResult res = IsValid (name, name);
 781
 782                                 if (res != AdditionResult.Success)
 783                                         return res;
 784
 785                                 Constraints constraints = null;
 786                                 if (constraints_list != null) {
 787                                         foreach (Constraints constraint in constraints_list) {
 788                                                 if (constraint.TypeParameter == name) {
 789                                                         constraints = constraint;
 790                                                         break;
 791                                                 }
 792                                         }
 793                                 }
 794
 795                                 type_params [i] = new TypeParameter (name, constraints, Location);
 796
 797                                 DefineName (name, type_params [i]);
 798                         }
 799
 800                         return AdditionResult.Success;
 801                 }
 802
 803                 public TypeParameter[] TypeParameters {
 804                         get {
 805                                 return type_params;
 806                         }
 807                 }
 808
 809                 public TypeParameterExpr LookupGeneric (string name, Location loc)
 810                 {
 811                         if (TypeParameters != null) {
 812                                 foreach (TypeParameter type_param in TypeParameters) {
 813                                         if (type_param.Name != name)
 814                                                 continue;
 815
 816                                         return new TypeParameterExpr (type_param, loc);
 817                                 }
 818                         }
 819
 820                         if (parent != null)
 821                                 return parent.LookupGeneric (name, loc);
 822
 823                         return null;
 824                 }
 825         }
 826
 827         /// <summary>
 828         ///   This is a readonly list of MemberInfo's.
 829         /// </summary>
 830         public class MemberList : IList {
 831                 public readonly IList List;
 832                 int count;
 833
 834                 /// <summary>
 835                 ///   Create a new MemberList from the given IList.
 836                 /// </summary>
 837                 public MemberList (IList list)
 838                 {
 839                         if (list != null)
 840                                 this.List = list;
 841                         else
 842                                 this.List = new ArrayList ();
 843                         count = List.Count;
 844                 }
 845
 846                 /// <summary>
 847                 ///   Concatenate the ILists `first' and `second' to a new MemberList.
 848                 /// </summary>
 849                 public MemberList (IList first, IList second)
 850                 {
 851                         ArrayList list = new ArrayList ();
 852                         list.AddRange (first);
 853                         list.AddRange (second);
 854                         count = list.Count;
 855                         List = list;
 856                 }
 857
 858                 public static readonly MemberList Empty = new MemberList (new ArrayList ());
 859
 860                 /// <summary>
 861                 ///   Cast the MemberList into a MemberInfo[] array.
 862                 /// </summary>
 863                 /// <remarks>
 864                 ///   This is an expensive operation, only use it if it's really necessary.
 865                 /// </remarks>
 866                 public static explicit operator MemberInfo [] (MemberList list)
 867                 {
 868                         Timer.StartTimer (TimerType.MiscTimer);
 869                         MemberInfo [] result = new MemberInfo [list.Count];
 870                         list.CopyTo (result, 0);
 871                         Timer.StopTimer (TimerType.MiscTimer);
 872                         return result;
 873                 }
 874
 875                 // ICollection
 876
 877                 public int Count {
 878                         get {
 879                                 return count;
 880                         }
 881                 }
 882
 883                 public bool IsSynchronized {
 884                         get {
 885                                 return List.IsSynchronized;
 886                         }
 887                 }
 888
 889                 public object SyncRoot {
 890                         get {
 891                                 return List.SyncRoot;
 892                         }
 893                 }
 894
 895                 public void CopyTo (Array array, int index)
 896                 {
 897                         List.CopyTo (array, index);
 898                 }
 899
 900                 // IEnumerable
 901
 902                 public IEnumerator GetEnumerator ()
 903                 {
 904                         return List.GetEnumerator ();
 905                 }
 906
 907                 // IList
 908
 909                 public bool IsFixedSize {
 910                         get {
 911                                 return true;
 912                         }
 913                 }
 914
 915                 public bool IsReadOnly {
 916                         get {
 917                                 return true;
 918                         }
 919                 }
 920
 921                 object IList.this [int index] {
 922                         get {
 923                                 return List [index];
 924                         }
 925
 926                         set {
 927                                 throw new NotSupportedException ();
 928                         }
 929                 }
 930
 931                 // FIXME: try to find out whether we can avoid the cast in this indexer.
 932                 public MemberInfo this [int index] {
 933                         get {
 934                                 return (MemberInfo) List [index];
 935                         }
 936                 }
 937
 938                 public int Add (object value)
 939                 {
 940                         throw new NotSupportedException ();
 941                 }
 942
 943                 public void Clear ()
 944                 {
 945                         throw new NotSupportedException ();
 946                 }
 947
 948                 public bool Contains (object value)
 949                 {
 950                         return List.Contains (value);
 951                 }
 952
 953                 public int IndexOf (object value)
 954                 {
 955                         return List.IndexOf (value);
 956                 }
 957
 958                 public void Insert (int index, object value)
 959                 {
 960                         throw new NotSupportedException ();
 961                 }
 962
 963                 public void Remove (object value)
 964                 {
 965                         throw new NotSupportedException ();
 966                 }
 967
 968                 public void RemoveAt (int index)
 969                 {
 970                         throw new NotSupportedException ();
 971                 }
 972         }
 973
 974         /// <summary>
 975         ///   This interface is used to get all members of a class when creating the
 976         ///   member cache.  It must be implemented by all DeclSpace derivatives which
 977         ///   want to support the member cache and by TypeHandle to get caching of
 978         ///   non-dynamic types.
 979         /// </summary>
 980         public interface IMemberContainer {
 981                 /// <summary>
 982                 ///   The name of the IMemberContainer.  This is only used for
 983                 ///   debugging purposes.
 984                 /// </summary>
 985                 string Name {
 986                         get;
 987                 }
 988
 989                 /// <summary>
 990                 ///   The type of this IMemberContainer.
 991                 /// </summary>
 992                 Type Type {
 993                         get;
 994                 }
 995
 996                 /// <summary>
 997                 ///   Returns the IMemberContainer of the parent class or null if this
 998                 ///   is an interface or TypeManger.object_type.
 999                 ///   This is used when creating the member cache for a class to get all
1000                 ///   members from the parent class.
1001                 /// </summary>
1002                 IMemberContainer Parent {
1003                         get;
1004                 }
1005
1006                 /// <summary>
1007                 ///   Whether this is an interface.
1008                 /// </summary>
1009                 bool IsInterface {
1010                         get;
1011                 }
1012
1013                 /// <summary>
1014                 ///   Returns all members of this class with the corresponding MemberTypes
1015                 ///   and BindingFlags.
1016                 /// </summary>
1017                 /// <remarks>
1018                 ///   When implementing this method, make sure not to return any inherited
1019                 ///   members and check the MemberTypes and BindingFlags properly.
1020                 ///   Unfortunately, System.Reflection is lame and doesn't provide a way to
1021                 ///   get the BindingFlags (static/non-static,public/non-public) in the
1022                 ///   MemberInfo class, but the cache needs this information.  That's why
1023                 ///   this method is called multiple times with different BindingFlags.
1024                 /// </remarks>
1025                 MemberList GetMembers (MemberTypes mt, BindingFlags bf);
1026
1027                 /// <summary>
1028                 ///   Return the container's member cache.
1029                 /// </summary>
1030                 MemberCache MemberCache {
1031                         get;
1032                 }
1033         }
1034
1035         /// <summary>
1036         ///   The MemberCache is used by dynamic and non-dynamic types to speed up
1037         ///   member lookups.  It has a member name based hash table; it maps each member
1038         ///   name to a list of CacheEntry objects.  Each CacheEntry contains a MemberInfo
1039         ///   and the BindingFlags that were initially used to get it.  The cache contains
1040         ///   all members of the current class and all inherited members.  If this cache is
1041         ///   for an interface types, it also contains all inherited members.
1042         ///
1043         ///   There are two ways to get a MemberCache:
1044         ///   * if this is a dynamic type, lookup the corresponding DeclSpace and then
1045         ///     use the DeclSpace.MemberCache property.
1046         ///   * if this not a dynamic type, call TypeHandle.GetTypeHandle() to get a
1047         ///     TypeHandle instance for the type and then use TypeHandle.MemberCache.
1048         /// </summary>
1049         public class MemberCache {
1050                 public readonly IMemberContainer Container;
1051                 protected Hashtable member_hash;
1052                 protected Hashtable method_hash;
1053                 protected Hashtable interface_hash;
1054
1055                 /// <summary>
1056                 ///   Create a new MemberCache for the given IMemberContainer `container'.
1057                 /// </summary>
1058                 public MemberCache (IMemberContainer container)
1059                 {
1060                         this.Container = container;
1061
1062                         Timer.IncrementCounter (CounterType.MemberCache);
1063                         Timer.StartTimer (TimerType.CacheInit);
1064
1065                         interface_hash = new Hashtable ();
1066
1067                         // If we have a parent class (we have a parent class unless we're
1068                         // TypeManager.object_type), we deep-copy its MemberCache here.
1069                         if (Container.IsInterface) {
1070                                 MemberCache parent;
1071                                 if (Container.Parent != null)
1072                                         parent = Container.Parent.MemberCache;
1073                                 else
1074                                         parent = TypeHandle.ObjectType.MemberCache;
1075                                 member_hash = SetupCacheForInterface (parent);
1076                         } else if (Container.Parent != null)
1077                                 member_hash = SetupCache (Container.Parent.MemberCache);
1078                         else
1079                                 member_hash = new Hashtable ();
1080
1081                         // If this is neither a dynamic type nor an interface, create a special
1082                         // method cache with all declared and inherited methods.
1083                         Type type = container.Type;
1084                         if (!(type is TypeBuilder) && !type.IsInterface) {
1085                                 method_hash = new Hashtable ();
1086                                 AddMethods (type);
1087                         }
1088
1089                         // Add all members from the current class.
1090                         AddMembers (Container);
1091
1092                         Timer.StopTimer (TimerType.CacheInit);
1093                 }
1094
1095                 /// <summary>
1096                 ///   Bootstrap this member cache by doing a deep-copy of our parent.
1097                 /// </summary>
1098                 Hashtable SetupCache (MemberCache parent)
1099                 {
1100                         Hashtable hash = new Hashtable ();
1101
1102                         IDictionaryEnumerator it = parent.member_hash.GetEnumerator ();
1103                         while (it.MoveNext ()) {
1104                                 hash [it.Key] = ((ArrayList) it.Value).Clone ();
1105                         }
1106
1107                         return hash;
1108                 }
1109
1110                 void AddInterfaces (MemberCache parent)
1111                 {
1112                         foreach (Type iface in parent.interface_hash.Keys) {
1113                                 if (!interface_hash.Contains (iface))
1114                                         interface_hash.Add (iface, true);
1115                         }
1116                 }
1117
1118                 /// <summary>
1119                 ///   Add the contents of `new_hash' to `hash'.
1120                 /// </summary>
1121                 void AddHashtable (Hashtable hash, Hashtable new_hash)
1122                 {
1123                         IDictionaryEnumerator it = new_hash.GetEnumerator ();
1124                         while (it.MoveNext ()) {
1125                                 ArrayList list = (ArrayList) hash [it.Key];
1126                                 if (list != null)
1127                                         list.AddRange ((ArrayList) it.Value);
1128                                 else
1129                                         hash [it.Key] = ((ArrayList) it.Value).Clone ();
1130                         }
1131                 }
1132
1133                 /// <summary>
1134                 ///   Bootstrap the member cache for an interface type.
1135                 ///   Type.GetMembers() won't return any inherited members for interface types,
1136                 ///   so we need to do this manually.  Interfaces also inherit from System.Object.
1137                 /// </summary>
1138                 Hashtable SetupCacheForInterface (MemberCache parent)
1139                 {
1140                         Hashtable hash = SetupCache (parent);
1141                         Type [] ifaces = TypeManager.GetInterfaces (Container.Type);
1142
1143                         foreach (Type iface in ifaces) {
1144                                 if (interface_hash.Contains (iface))
1145                                         continue;
1146                                 interface_hash.Add (iface, true);
1147
1148                                 IMemberContainer iface_container =
1149                                         TypeManager.LookupMemberContainer (iface);
1150
1151                                 MemberCache iface_cache = iface_container.MemberCache;
1152
1153                                 AddHashtable (hash, iface_cache.member_hash);
1154                                 AddInterfaces (iface_cache);
1155                         }
1156
1157                         return hash;
1158                 }
1159
1160                 /// <summary>
1161                 ///   Add all members from class `container' to the cache.
1162                 /// </summary>
1163                 void AddMembers (IMemberContainer container)
1164                 {
1165                         // We need to call AddMembers() with a single member type at a time
1166                         // to get the member type part of CacheEntry.EntryType right.
1167                         AddMembers (MemberTypes.Constructor, container);
1168                         AddMembers (MemberTypes.Field, container);
1169                         AddMembers (MemberTypes.Method, container);
1170                         AddMembers (MemberTypes.Property, container);
1171                         AddMembers (MemberTypes.Event, container);
1172                         // Nested types are returned by both Static and Instance searches.
1173                         AddMembers (MemberTypes.NestedType,
1174                                     BindingFlags.Static | BindingFlags.Public, container);
1175                         AddMembers (MemberTypes.NestedType,
1176                                     BindingFlags.Static | BindingFlags.NonPublic, container);
1177                 }
1178
1179                 void AddMembers (MemberTypes mt, IMemberContainer container)
1180                 {
1181                         AddMembers (mt, BindingFlags.Static | BindingFlags.Public, container);
1182                         AddMembers (mt, BindingFlags.Static | BindingFlags.NonPublic, container);
1183                         AddMembers (mt, BindingFlags.Instance | BindingFlags.Public, container);
1184                         AddMembers (mt, BindingFlags.Instance | BindingFlags.NonPublic, container);
1185                 }
1186
1187                 /// <summary>
1188                 ///   Add all members from class `container' with the requested MemberTypes and
1189                 ///   BindingFlags to the cache.  This method is called multiple times with different
1190                 ///   MemberTypes and BindingFlags.
1191                 /// </summary>
1192                 void AddMembers (MemberTypes mt, BindingFlags bf, IMemberContainer container)
1193                 {
1194                         MemberList members = container.GetMembers (mt, bf);
1195                         BindingFlags new_bf = (container == Container) ?
1196                                 bf | BindingFlags.DeclaredOnly : bf;
1197
1198                         foreach (MemberInfo member in members) {
1199                                 string name = member.Name;
1200
1201                                 // We use a name-based hash table of ArrayList's.
1202                                 ArrayList list = (ArrayList) member_hash [name];
1203                                 if (list == null) {
1204                                         list = new ArrayList ();
1205                                         member_hash.Add (name, list);
1206                                 }
1207
1208                                 // When this method is called for the current class, the list will
1209                                 // already contain all inherited members from our parent classes.
1210                                 // We cannot add new members in front of the list since this'd be an
1211                                 // expensive operation, that's why the list is sorted in reverse order
1212                                 // (ie. members from the current class are coming last).
1213                                 list.Add (new CacheEntry (container, member, mt, bf));
1214                         }
1215                 }
1216
1217                 /// <summary>
1218                 ///   Add all declared and inherited methods from class `type' to the method cache.
1219                 /// </summary>
1220                 void AddMethods (Type type)
1221                 {
1222                         AddMethods (BindingFlags.Static | BindingFlags.Public |
1223                                     BindingFlags.FlattenHierarchy, type);
1224                         AddMethods (BindingFlags.Static | BindingFlags.NonPublic |
1225                                     BindingFlags.FlattenHierarchy, type);
1226                         AddMethods (BindingFlags.Instance | BindingFlags.Public, type);
1227                         AddMethods (BindingFlags.Instance | BindingFlags.NonPublic, type);
1228                 }
1229
1230                 void AddMethods (BindingFlags bf, Type type)
1231                 {
1232                         MemberInfo [] members = type.GetMethods (bf);
1233
1234                         foreach (MethodBase member in members) {
1235                                 string name = member.Name;
1236
1237                                 // Varargs methods aren't allowed in C# code.
1238                                 if ((member.CallingConvention & CallingConventions.VarArgs) != 0)
1239                                         continue;
1240
1241                                 // We use a name-based hash table of ArrayList's.
1242                                 ArrayList list = (ArrayList) method_hash [name];
1243                                 if (list == null) {
1244                                         list = new ArrayList ();
1245                                         method_hash.Add (name, list);
1246                                 }
1247
1248                                 // Unfortunately, the elements returned by Type.GetMethods() aren't
1249                                 // sorted so we need to do this check for every member.
1250                                 BindingFlags new_bf = bf;
1251                                 if (member.DeclaringType == type)
1252                                         new_bf |= BindingFlags.DeclaredOnly;
1253
1254                                 list.Add (new CacheEntry (Container, member, MemberTypes.Method, new_bf));
1255                         }
1256                 }
1257
1258                 /// <summary>
1259                 ///   Compute and return a appropriate `EntryType' magic number for the given
1260                 ///   MemberTypes and BindingFlags.
1261                 /// </summary>
1262                 protected static EntryType GetEntryType (MemberTypes mt, BindingFlags bf)
1263                 {
1264                         EntryType type = EntryType.None;
1265
1266                         if ((mt & MemberTypes.Constructor) != 0)
1267                                 type |= EntryType.Constructor;
1268                         if ((mt & MemberTypes.Event) != 0)
1269                                 type |= EntryType.Event;
1270                         if ((mt & MemberTypes.Field) != 0)
1271                                 type |= EntryType.Field;
1272                         if ((mt & MemberTypes.Method) != 0)
1273                                 type |= EntryType.Method;
1274                         if ((mt & MemberTypes.Property) != 0)
1275                                 type |= EntryType.Property;
1276                         // Nested types are returned by static and instance searches.
1277                         if ((mt & MemberTypes.NestedType) != 0)
1278                                 type |= EntryType.NestedType | EntryType.Static | EntryType.Instance;
1279
1280                         if ((bf & BindingFlags.Instance) != 0)
1281                                 type |= EntryType.Instance;
1282                         if ((bf & BindingFlags.Static) != 0)
1283                                 type |= EntryType.Static;
1284                         if ((bf & BindingFlags.Public) != 0)
1285                                 type |= EntryType.Public;
1286                         if ((bf & BindingFlags.NonPublic) != 0)
1287                                 type |= EntryType.NonPublic;
1288                         if ((bf & BindingFlags.DeclaredOnly) != 0)
1289                                 type |= EntryType.Declared;
1290
1291                         return type;
1292                 }
1293
1294                 /// <summary>
1295                 ///   The `MemberTypes' enumeration type is a [Flags] type which means that it may
1296                 ///   denote multiple member types.  Returns true if the given flags value denotes a
1297                 ///   single member types.
1298                 /// </summary>
1299                 public static bool IsSingleMemberType (MemberTypes mt)
1300                 {
1301                         switch (mt) {
1302                         case MemberTypes.Constructor:
1303                         case MemberTypes.Event:
1304                         case MemberTypes.Field:
1305                         case MemberTypes.Method:
1306                         case MemberTypes.Property:
1307                         case MemberTypes.NestedType:
1308                                 return true;
1309
1310                         default:
1311                                 return false;
1312                         }
1313                 }
1314
1315                 /// <summary>
1316                 ///   We encode the MemberTypes and BindingFlags of each members in a "magic"
1317                 ///   number to speed up the searching process.
1318                 /// </summary>
1319                 [Flags]
1320                 protected enum EntryType {
1321                         None            = 0x000,
1322
1323                         Instance        = 0x001,
1324                         Static          = 0x002,
1325                         MaskStatic      = Instance|Static,
1326
1327                         Public          = 0x004,
1328                         NonPublic       = 0x008,
1329                         MaskProtection  = Public|NonPublic,
1330
1331                         Declared        = 0x010,
1332
1333                         Constructor     = 0x020,
1334                         Event           = 0x040,
1335                         Field           = 0x080,
1336                         Method          = 0x100,
1337                         Property        = 0x200,
1338                         NestedType      = 0x400,
1339
1340                         MaskType        = Constructor|Event|Field|Method|Property|NestedType
1341                 }
1342
1343                 protected struct CacheEntry {
1344                         public readonly IMemberContainer Container;
1345                         public readonly EntryType EntryType;
1346                         public readonly MemberInfo Member;
1347
1348                         public CacheEntry (IMemberContainer container, MemberInfo member,
1349                                            MemberTypes mt, BindingFlags bf)
1350                         {
1351                                 this.Container = container;
1352                                 this.Member = member;
1353                                 this.EntryType = GetEntryType (mt, bf);
1354                         }
1355                 }
1356
1357                 /// <summary>
1358                 ///   This is called each time we're walking up one level in the class hierarchy
1359                 ///   and checks whether we can abort the search since we've already found what
1360                 ///   we were looking for.
1361                 /// </summary>
1362                 protected bool DoneSearching (ArrayList list)
1363                 {
1364                         //
1365                         // We've found exactly one member in the current class and it's not
1366                         // a method or constructor.
1367                         //
1368                         if (list.Count == 1 && !(list [0] is MethodBase))
1369                                 return true;
1370
1371                         //
1372                         // Multiple properties: we query those just to find out the indexer
1373                         // name
1374                         //
1375                         if ((list.Count > 0) && (list [0] is PropertyInfo))
1376                                 return true;
1377
1378                         return false;
1379                 }
1380
1381                 /// <summary>
1382                 ///   Looks up members with name `name'.  If you provide an optional
1383                 ///   filter function, it'll only be called with members matching the
1384                 ///   requested member name.
1385                 ///
1386                 ///   This method will try to use the cache to do the lookup if possible.
1387                 ///
1388                 ///   Unlike other FindMembers implementations, this method will always
1389                 ///   check all inherited members - even when called on an interface type.
1390                 ///
1391                 ///   If you know that you're only looking for methods, you should use
1392                 ///   MemberTypes.Method alone since this speeds up the lookup a bit.
1393                 ///   When doing a method-only search, it'll try to use a special method
1394                 ///   cache (unless it's a dynamic type or an interface) and the returned
1395                 ///   MemberInfo's will have the correct ReflectedType for inherited methods.
1396                 ///   The lookup process will automatically restart itself in method-only
1397                 ///   search mode if it discovers that it's about to return methods.
1398                 /// </summary>
1399                 ArrayList global = new ArrayList ();
1400                 bool using_global = false;
1401
1402                 public MemberList FindMembers (MemberTypes mt, BindingFlags bf, string name,
1403                                                MemberFilter filter, object criteria)
1404                 {
1405                         if (using_global)
1406                                 throw new Exception ();
1407
1408                         bool declared_only = (bf & BindingFlags.DeclaredOnly) != 0;
1409                         bool method_search = mt == MemberTypes.Method;
1410                         // If we have a method cache and we aren't already doing a method-only search,
1411                         // then we restart a method search if the first match is a method.
1412                         bool do_method_search = !method_search && (method_hash != null);
1413
1414                         ArrayList applicable;
1415
1416                         // If this is a method-only search, we try to use the method cache if
1417                         // possible; a lookup in the method cache will return a MemberInfo with
1418                         // the correct ReflectedType for inherited methods.
1419
1420                         if (method_search && (method_hash != null))
1421                                 applicable = (ArrayList) method_hash [name];
1422                         else
1423                                 applicable = (ArrayList) member_hash [name];
1424
1425                         if (applicable == null)
1426                                 return MemberList.Empty;
1427
1428                         //
1429                         // 32  slots gives 53 rss/54 size
1430                         // 2/4 slots gives 55 rss
1431                         //
1432                         // Strange: from 25,000 calls, only 1,800
1433                         // are above 2.  Why does this impact it?
1434                         //
1435                         global.Clear ();
1436                         using_global = true;
1437
1438                         Timer.StartTimer (TimerType.CachedLookup);
1439
1440                         EntryType type = GetEntryType (mt, bf);
1441
1442                         IMemberContainer current = Container;
1443
1444                         // `applicable' is a list of all members with the given member name `name'
1445                         // in the current class and all its parent classes.  The list is sorted in
1446                         // reverse order due to the way how the cache is initialy created (to speed
1447                         // things up, we're doing a deep-copy of our parent).
1448
1449                         for (int i = applicable.Count-1; i >= 0; i--) {
1450                                 CacheEntry entry = (CacheEntry) applicable [i];
1451
1452                                 // This happens each time we're walking one level up in the class
1453                                 // hierarchy.  If we're doing a DeclaredOnly search, we must abort
1454                                 // the first time this happens (this may already happen in the first
1455                                 // iteration of this loop if there are no members with the name we're
1456                                 // looking for in the current class).
1457                                 if (entry.Container != current) {
1458                                         if (declared_only || DoneSearching (global))
1459                                                 break;
1460
1461                                         current = entry.Container;
1462                                 }
1463
1464                                 // Is the member of the correct type ?
1465                                 if ((entry.EntryType & type & EntryType.MaskType) == 0)
1466                                         continue;
1467
1468                                 // Is the member static/non-static ?
1469                                 if ((entry.EntryType & type & EntryType.MaskStatic) == 0)
1470                                         continue;
1471
1472                                 // Apply the filter to it.
1473                                 if (filter (entry.Member, criteria)) {
1474                                         if ((entry.EntryType & EntryType.MaskType) != EntryType.Method)
1475                                                 do_method_search = false;
1476                                         global.Add (entry.Member);
1477                                 }
1478                         }
1479
1480                         Timer.StopTimer (TimerType.CachedLookup);
1481
1482                         // If we have a method cache and we aren't already doing a method-only
1483                         // search, we restart in method-only search mode if the first match is
1484                         // a method.  This ensures that we return a MemberInfo with the correct
1485                         // ReflectedType for inherited methods.
1486                         if (do_method_search && (global.Count > 0)){
1487                                 using_global = false;
1488
1489                                 return FindMembers (MemberTypes.Method, bf, name, filter, criteria);
1490                         }
1491
1492                         using_global = false;
1493                         MemberInfo [] copy = new MemberInfo [global.Count];
1494                         global.CopyTo (copy);
1495                         return new MemberList (copy);
1496                 }
1497         }
1498 }