mcs/mcs/membercache.cs

   1 //
   2 // membercache.cs: A container for all member lookups
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //         Marek Safar (marek.safar@gmail.com)
   6 //
   7 // Dual licensed under the terms of the MIT X11 or GNU GPL
   8 //
   9 // Copyright 2001 Ximian, Inc (http://www.ximian.com)
  10 // Copyright 2004-2010 Novell, Inc
  11 //
  12 //
  13
  14 using System;
  15 using System.Text;
  16 using System.Collections.Generic;
  17 using System.Reflection;
  18 using System.Linq;
  19
  20 namespace Mono.CSharp {
  21
  22         [Flags]
  23         public enum MemberKind
  24         {
  25                 Constructor = 1,
  26                 Event = 1 << 1,
  27                 Field = 1 << 2,
  28                 Method = 1 << 3,
  29                 Property = 1 << 4,
  30                 Indexer = 1 << 5,
  31                 Operator = 1 << 6,
  32                 Destructor      = 1 << 7,
  33
  34                 Class           = 1 << 11,
  35                 Struct          = 1 << 12,
  36                 Delegate        = 1 << 13,
  37                 Enum            = 1 << 14,
  38                 Interface       = 1 << 15,
  39                 TypeParameter = 1 << 16,
  40
  41                 ArrayType = 1 << 19,
  42                 PointerType = 1 << 20,
  43                 InternalCompilerType = 1 << 21,
  44
  45                 NestedMask = Class | Struct | Delegate | Enum | Interface,
  46                 GenericMask = Method | Class | Struct | Delegate | Interface,
  47                 MaskType = Constructor | Event | Field | Method | Property | Indexer | Operator | Destructor | NestedMask,
  48                 All = MaskType
  49         }
  50
  51         [Flags]
  52         public enum BindingRestriction
  53         {
  54                 None = 0,
  55
  56                 // Inspect only queried type members
  57                 DeclaredOnly = 1 << 1,
  58
  59                 // Exclude static
  60                 InstanceOnly = 1 << 2,
  61
  62                 NoAccessors = 1 << 3
  63         }
  64
  65         public struct MemberFilter : IEquatable<MemberSpec>
  66         {
  67                 public readonly string Name;
  68                 public readonly MemberKind Kind;
  69                 public readonly AParametersCollection Parameters;
  70                 public readonly TypeSpec MemberType;
  71
  72                 int arity; // -1 to ignore the check
  73
  74                 private MemberFilter (string name, MemberKind kind)
  75                 {
  76                         Name = name;
  77                         Kind = kind;
  78                         Parameters = null;
  79                         MemberType = null;
  80                         arity = -1;
  81                 }
  82
  83                 public MemberFilter (MethodSpec m)
  84                 {
  85                         Name = m.Name;
  86                         Kind = MemberKind.Method;
  87                         Parameters = m.Parameters;
  88                         MemberType = m.ReturnType;
  89                         arity = m.Arity;
  90                 }
  91
  92                 public MemberFilter (string name, int arity, MemberKind kind, AParametersCollection param, TypeSpec type)
  93                 {
  94                         Name = name;
  95                         Kind = kind;
  96                         Parameters = param;
  97                         MemberType = type;
  98                         this.arity = arity;
  99                 }
 100
 101                 public static MemberFilter Constructor (AParametersCollection param)
 102                 {
 103                         return new MemberFilter (System.Reflection.ConstructorInfo.ConstructorName, 0, MemberKind.Constructor, param, null);
 104                 }
 105
 106                 public static MemberFilter Property (string name, TypeSpec type)
 107                 {
 108                         return new MemberFilter (name, 0, MemberKind.Property, null, type);
 109                 }
 110
 111                 public static MemberFilter Field (string name, TypeSpec type)
 112                 {
 113                         return new MemberFilter (name, 0, MemberKind.Field, null, type);
 114                 }
 115
 116                 public static MemberFilter Method (string name, int arity, AParametersCollection param, TypeSpec type)
 117                 {
 118                         return new MemberFilter (name, arity, MemberKind.Method, param, type);
 119                 }
 120
 121                 #region IEquatable<MemberSpec> Members
 122
 123                 public bool Equals (MemberSpec other)
 124                 {
 125                         // Is the member of the correct type ?
 126                         // TODO: Isn't this redundant ?
 127                         if ((other.Kind & Kind & MemberKind.MaskType) == 0)
 128                                 return false;
 129
 130                         // Check arity when not disabled
 131                         if (arity >= 0 && arity != other.Arity)
 132                                 return false;
 133
 134                         if (Parameters != null) {
 135                                 if (other is IParametersMember) {
 136                                         var other_param = ((IParametersMember) other).Parameters;
 137                                         if (!TypeSpecComparer.Override.IsEqual (Parameters, other_param))
 138                                                 return false;
 139                                 } else {
 140                                         return false;
 141                                 }
 142                         }
 143
 144                         if (MemberType != null) {
 145                                 if (other is IInterfaceMemberSpec) {
 146                                         var other_type = ((IInterfaceMemberSpec) other).MemberType;
 147                                         if (!TypeSpecComparer.Override.IsEqual (other_type, MemberType))
 148                                                 return false;
 149                                 } else {
 150                                         return false;
 151                                 }
 152                         }
 153
 154                         return true;
 155                 }
 156
 157                 #endregion
 158         }
 159
 160         //
 161         // The MemberCache is the main members container used by compiler. It contains
 162         // all members imported or defined during compilation using on demand filling
 163         // process. Inflated containers are also using MemberCache to make inflated
 164         // members look like normal definition.
 165         //
 166         // All of the methods are performance and memory sensitive as the MemberCache
 167         // is the underlying engine of all member based operations.
 168         //
 169         public class MemberCache
 170         {
 171                 enum StateFlags
 172                 {
 173                         HasConversionOperator = 1 << 1,
 174                         HasUserOperator = 1 << 2
 175                 }
 176
 177                 readonly Dictionary<string, IList<MemberSpec>> member_hash;
 178                 Dictionary<string, MemberSpec[]> locase_members;
 179                 IList<MethodSpec> missing_abstract;
 180                 StateFlags state;
 181
 182                 public static readonly string IndexerNameAlias = "<this>";
 183
 184                 public static readonly MemberCache Empty = new MemberCache (0);
 185
 186                 public MemberCache ()
 187                         : this (16)
 188                 {
 189                 }
 190
 191                 public MemberCache (int capacity)
 192                 {
 193                         member_hash = new Dictionary<string, IList<MemberSpec>> (capacity);
 194                 }
 195
 196                 public MemberCache (MemberCache cache)
 197                         : this (cache.member_hash.Count)
 198                 {
 199                         this.state = cache.state;
 200                 }
 201
 202                 //
 203                 // Creates a new MemberCache for the given `container'.
 204                 //
 205                 public MemberCache (TypeContainer container)
 206                         : this ()                               // TODO: Optimize the size
 207                 {
 208                 }
 209
 210                 //
 211                 // Member-cache does not contain base members but it does
 212                 // contain all base interface members, so the Lookup code
 213                 // can use simple inheritance rules.
 214                 //
 215                 public void AddInterface (TypeSpec iface)
 216                 {
 217                         var cache = iface.MemberCache;
 218
 219                         IList<MemberSpec> list;
 220                         foreach (var entry in cache.member_hash) {
 221                                 if (!member_hash.TryGetValue (entry.Key, out list)) {
 222                                         if (entry.Value.Count == 1) {
 223                                                 list = entry.Value;
 224                                         } else {
 225                                                 list = new List<MemberSpec> (entry.Value);
 226                                         }
 227
 228                                         member_hash.Add (entry.Key, list);
 229                                         continue;
 230                                 }
 231
 232                                 foreach (var ce in entry.Value) {
 233                                         if (ce.DeclaringType != iface)
 234                                                 break;
 235
 236                                         if (list.Contains (ce))
 237                                                 continue;
 238
 239                                         if (AddInterfaceMember (ce, ref list))
 240                                                 member_hash[entry.Key] = list;
 241                                 }
 242                         }
 243
 244                         // Add also all base interfaces
 245                         if (iface.Interfaces != null) {
 246                                 foreach (var base_iface in iface.Interfaces)
 247                                         AddInterface (base_iface);
 248                         }
 249                 }
 250
 251                 public void AddMember (InterfaceMemberBase imb, string exlicitName, MemberSpec ms)
 252                 {
 253                         // Explicit names cannot be looked-up but can be used for
 254                         // collision checking (no name mangling needed)
 255                         if (imb.IsExplicitImpl)
 256                                 AddMember (exlicitName, ms);
 257                         else
 258                                 AddMember (ms);
 259                 }
 260
 261                 //
 262                 // Add non-explicit member to member cache
 263                 //
 264                 public void AddMember (MemberSpec ms)
 265                 {
 266                         AddMember (GetLookupName (ms), ms);
 267                 }
 268
 269                 void AddMember (string name, MemberSpec member)
 270                 {
 271                         if (member.Kind == MemberKind.Operator) {
 272                                 var dt = member.DeclaringType;
 273                                 if (dt == TypeManager.string_type || dt == TypeManager.delegate_type || dt == TypeManager.multicast_delegate_type) {
 274                                         // Some core types have user operators but they cannot be used as normal
 275                                         // user operators as they are predefined and therefore having different
 276                                         // rules (e.g. binary operators) by not setting the flag we hide them for
 277                                         // user conversions
 278                                         // TODO: Should I do this for all core types ?
 279                                 } else if (name == Operator.GetMetadataName (Operator.OpType.Implicit) || name == Operator.GetMetadataName (Operator.OpType.Explicit)) {
 280                                         state |= StateFlags.HasConversionOperator;
 281                                 } else {
 282                                         state |= StateFlags.HasUserOperator;
 283                                 }
 284                         }
 285
 286                         IList<MemberSpec> list;
 287                         if (!member_hash.TryGetValue (name, out list)) {
 288                                 member_hash.Add (name, new MemberSpec[] { member });
 289                                 return;
 290                         }
 291
 292                         if (member.DeclaringType.IsInterface) {
 293                                 if (AddInterfaceMember (member, ref list))
 294                                         member_hash[name] = list;
 295                         } else {
 296                                 if (list is MemberSpec[]) {
 297                                         list = new List<MemberSpec> () { list[0] };
 298                                         member_hash[name] = list;
 299                                 }
 300
 301                                 list.Add (member);
 302                         }
 303                 }
 304
 305                 //
 306                 // Ignores any base interface member which can be hidden
 307                 // by this interface
 308                 //
 309                 static bool AddInterfaceMember (MemberSpec member, ref IList<MemberSpec> existing)
 310                 {
 311                         var member_param = member is IParametersMember ? ((IParametersMember) member).Parameters : ParametersCompiled.EmptyReadOnlyParameters;
 312
 313                         //
 314                         // interface IA : IB { int Prop { set; } }
 315                         // interface IB { bool Prop { get; } }
 316                         //
 317                         // IB.Prop is never accessible from IA interface
 318                         //
 319                         for (int i = 0; i < existing.Count; ++i) {
 320                                 var entry = existing[i];
 321
 322                                 if (entry.Arity != member.Arity)
 323                                         continue;
 324
 325                                 if (entry is IParametersMember) {
 326                                         var entry_param = ((IParametersMember) entry).Parameters;
 327                                         if (!TypeSpecComparer.Override.IsEqual (entry_param, member_param))
 328                                                 continue;
 329                                 }
 330
 331                                 if (member.DeclaringType.ImplementsInterface (entry.DeclaringType)) {
 332                                         if (existing is MemberSpec[]) {
 333                                                 existing = new MemberSpec[] { member };
 334                                                 return true;
 335                                         }
 336
 337                                         existing.RemoveAt (i--);
 338                                         continue;
 339                                 }
 340
 341                                 if ((entry.DeclaringType == member.DeclaringType && entry.IsAccessor == member.IsAccessor) ||
 342                                         entry.DeclaringType.ImplementsInterface (member.DeclaringType))
 343                                         return false;
 344                         }
 345
 346                         if (existing is MemberSpec[]) {
 347                                 existing = new List<MemberSpec> () { existing[0], member };
 348                                 return true;
 349                         }
 350
 351                         existing.Add (member);
 352                         return false;
 353                 }
 354
 355                 public static MemberSpec FindMember (TypeSpec container, MemberFilter filter, BindingRestriction restrictions)
 356                 {
 357                         do {
 358                                 IList<MemberSpec> applicable;
 359                                 if (container.MemberCache.member_hash.TryGetValue (filter.Name, out applicable)) {
 360                                         // Start from the end because interface members are in reverse order
 361                                         for (int i = applicable.Count - 1; i >= 0; i--) {
 362                                                 var entry = applicable [i];
 363
 364                                                 if ((restrictions & BindingRestriction.InstanceOnly) != 0 && entry.IsStatic)
 365                                                         continue;
 366
 367                                                 if ((restrictions & BindingRestriction.NoAccessors) != 0 && entry.IsAccessor)
 368                                                         continue;
 369
 370                                                 if (!filter.Equals (entry))
 371                                                         continue;
 372
 373                                                 if ((restrictions & BindingRestriction.DeclaredOnly) != 0 && container.IsInterface && entry.DeclaringType != container)
 374                                                         continue;
 375
 376                                                 return entry;
 377                                         }
 378                                 }
 379
 380                                 if ((restrictions & BindingRestriction.DeclaredOnly) != 0)
 381                                         break;
 382
 383                                 container = container.BaseType;
 384                         } while (container != null);
 385
 386                         return null;
 387                 }
 388
 389                 //
 390                 // A special method to work with member lookup only. It returns a list of all members named @name
 391                 // starting from @container. It's very performance sensitive
 392                 //
 393                 public static IList<MemberSpec> FindMembers (TypeSpec container, string name, bool declaredOnly)
 394                 {
 395                         IList<MemberSpec> applicable;
 396
 397                         do {
 398                                 if (container.MemberCache.member_hash.TryGetValue (name, out applicable) || declaredOnly)
 399                                         return applicable;
 400
 401                                 container = container.BaseType;
 402                         } while (container != null);
 403
 404                         return null;
 405                 }
 406
 407                 //
 408                 // Finds the nested type in container
 409                 //
 410                 public static TypeSpec FindNestedType (TypeSpec container, string name, int arity)
 411                 {
 412                         IList<MemberSpec> applicable;
 413                         TypeSpec best_match = null;
 414                         do {
 415                                 // TODO: Don't know how to handle this yet
 416                                 // When resolving base type of nested type, parent type must have
 417                                 // base type resolved to scan full hierarchy correctly
 418                                 // Similarly MemberCacheTypes will inflate BaseType and Interfaces
 419                                 // based on type definition
 420                                 var tc = container.MemberDefinition as TypeContainer;
 421                                 if (tc != null)
 422                                         tc.DefineType ();
 423
 424                                 if (container.MemberCacheTypes.member_hash.TryGetValue (name, out applicable)) {
 425                                         for (int i = applicable.Count - 1; i >= 0; i--) {
 426                                                 var entry = applicable[i];
 427                                                 if ((entry.Kind & MemberKind.NestedMask) == 0)
 428                                                         continue;
 429
 430                                                 var ts = (TypeSpec) entry;
 431                                                 if (arity == ts.Arity)
 432                                                         return ts;
 433
 434                                                 if (arity < 0) {
 435                                                         if (best_match == null) {
 436                                                                 best_match = ts;
 437                                                         } else if (System.Math.Abs (ts.Arity + arity) < System.Math.Abs (ts.Arity + arity)) {
 438                                                                 best_match = ts;
 439                                                         }
 440                                                 }
 441                                         }
 442                                 }
 443
 444                                 container = container.BaseType;
 445                         } while (container != null);
 446
 447                         return best_match;
 448                 }
 449
 450                 //
 451                 // Looks for extension methods with defined name and extension type
 452                 //
 453                 public List<MethodSpec> FindExtensionMethods (TypeSpec invocationType, TypeSpec extensionType, string name, int arity)
 454                 {
 455                         IList<MemberSpec> entries;
 456                         if (!member_hash.TryGetValue (name, out entries))
 457                                 return null;
 458
 459                         List<MethodSpec> candidates = null;
 460                         foreach (var entry in entries) {
 461                                 if (entry.Kind != MemberKind.Method || (arity > 0 && entry.Arity != arity))
 462                                         continue;
 463
 464                                 var ms = (MethodSpec) entry;
 465                                 if (!ms.IsExtensionMethod)
 466                                         continue;
 467
 468                                 if (!ms.IsAccessible (invocationType))
 469                                         continue;
 470
 471                                 // TODO: CodeGen.Assembly.Builder
 472                                 if ((ms.DeclaringType.Modifiers & Modifiers.INTERNAL) != 0 &&
 473                                         !TypeManager.IsThisOrFriendAssembly (CodeGen.Assembly.Builder, ms.Assembly))
 474                                         continue;
 475
 476                                 if (candidates == null)
 477                                         candidates = new List<MethodSpec> ();
 478                                 candidates.Add (ms);
 479                         }
 480
 481                         return candidates;
 482                 }
 483
 484                 //
 485                 // Returns base members of @member member if no exact match is found @bestCandidate returns
 486                 // the best match
 487                 //
 488                 public static MemberSpec FindBaseMember (MemberCore member, out MemberSpec bestCandidate)
 489                 {
 490                         bestCandidate = null;
 491                         var container = member.Parent.PartialContainer.Definition;
 492                         if (!container.IsInterface)
 493                                 container = container.BaseType;
 494
 495                         string name = GetLookupName (member);
 496                         IList<MemberSpec> applicable;
 497                         var member_param = member is IParametersMember ? ((IParametersMember) member).Parameters : null;
 498
 499                         var mkind = GetMemberCoreKind (member);
 500                         bool member_with_accessors = mkind == MemberKind.Indexer || mkind == MemberKind.Property;
 501
 502                         do {
 503                                 if (container.MemberCache.member_hash.TryGetValue (name, out applicable)) {
 504                                         for (int i = 0; i < applicable.Count; ++i) {
 505                                                 var entry = applicable [i];
 506
 507                                                 if ((entry.Modifiers & Modifiers.PRIVATE) != 0)
 508                                                         continue;
 509
 510                                                 if ((entry.Modifiers & Modifiers.AccessibilityMask) == Modifiers.INTERNAL) {
 511                                                         if (!TypeManager.IsThisOrFriendAssembly (member.Assembly, entry.Assembly))
 512                                                                 continue;
 513                                                 }
 514
 515                                                 //
 516                                                 // Is the member of the correct type ?
 517                                                 // Destructors are ignored as they cannot be overridden by user
 518                                                 if ((entry.Kind & ~MemberKind.Destructor & mkind & MemberKind.MaskType) == 0) {
 519                                                         if ((entry.Kind & MemberKind.Destructor) == 0 && (member_param == null || !(entry is IParametersMember))) {
 520                                                                 bestCandidate = entry;
 521                                                                 return null;
 522                                                         }
 523
 524                                                         continue;
 525                                                 }
 526
 527                                                 if (entry.Kind != mkind) {
 528                                                         if (bestCandidate == null)
 529                                                                 bestCandidate = entry;
 530
 531                                                         continue;
 532                                                 }
 533
 534                                                 if (member_param != null) {
 535                                                         // Check arity match
 536                                                         int arity = member.MemberName.Arity;
 537                                                         if (arity != entry.Arity)
 538                                                                 continue;
 539
 540                                                         var pm = entry as IParametersMember;
 541                                                         if (pm == null)
 542                                                                 continue;
 543
 544                                                         if (entry.IsAccessor != member is AbstractPropertyEventMethod)
 545                                                                 continue;
 546
 547                                                         if (!TypeSpecComparer.Override.IsEqual (pm.Parameters, member_param))
 548                                                                 continue;
 549                                                 }
 550
 551                                                 //
 552                                                 // Skip override members with accessors they may not fully implement the base member
 553                                                 //
 554                                                 if (member_with_accessors) {
 555                                                         if ((entry.Modifiers & (Modifiers.OVERRIDE | Modifiers.SEALED)) == Modifiers.OVERRIDE) {
 556                                                                 //
 557                                                                 // Set candidate to member override to flag we found an implementation
 558                                                                 //
 559                                                                 bestCandidate = entry;
 560                                                                 continue;
 561                                                         }
 562                                                 } else {
 563                                                         bestCandidate = null;
 564                                                 }
 565
 566                                                 return entry;
 567                                         }
 568                                 }
 569
 570                                 if (container.IsInterface)
 571                                         break;
 572
 573                                 container = container.BaseType;
 574                         } while (container != null);
 575
 576                         return null;
 577                 }
 578
 579                 //
 580                 // Returns inflated version of MemberSpec, it works similarly to
 581                 // SRE TypeBuilder.GetMethod
 582                 //
 583                 public static T GetMember<T> (TypeSpec container, T spec) where T : MemberSpec
 584                 {
 585                         IList<MemberSpec> applicable;
 586                         if (container.MemberCache.member_hash.TryGetValue (GetLookupName (spec), out applicable)) {
 587                                 for (int i = applicable.Count - 1; i >= 0; i--) {
 588                                         var entry = applicable[i];
 589                                         if (entry.MemberDefinition == spec.MemberDefinition)
 590                                                 return (T) entry;
 591                                 }
 592                         }
 593
 594                         throw new InternalErrorException ("Missing member `{0}' on inflated type `{1}'",
 595                                 spec.GetSignatureForError (), container.GetSignatureForError ());
 596                 }
 597
 598                 static MemberKind GetMemberCoreKind (MemberCore member)
 599                 {
 600                         if (member is FieldBase)
 601                                 return MemberKind.Field;
 602                         if (member is Indexer)
 603                                 return MemberKind.Indexer;
 604                         if (member is Class)
 605                                 return MemberKind.Class;
 606                         if (member is Struct)
 607                                 return MemberKind.Struct;
 608                         if (member is Destructor)
 609                                 return MemberKind.Destructor;
 610                         if (member is Method)
 611                                 return MemberKind.Method;
 612                         if (member is Property)
 613                                 return MemberKind.Property;
 614                         if (member is EventField)
 615                                 return MemberKind.Event;
 616                         if (member is Interface)
 617                                 return MemberKind.Interface;
 618                         if (member is EventProperty)
 619                                 return MemberKind.Event;
 620
 621                         throw new NotImplementedException (member.GetType ().ToString ());
 622                 }
 623
 624                 public static IList<MemberSpec> GetCompletitionMembers (TypeSpec container, string name)
 625                 {
 626                         var matches = new List<MemberSpec> ();
 627                         foreach (var entry in container.MemberCache.member_hash) {
 628                                 foreach (var name_entry in entry.Value) {
 629                                         if (name_entry.IsAccessor)
 630                                                 continue;
 631
 632                                         if ((name_entry.Kind & (MemberKind.Constructor | MemberKind.Destructor | MemberKind.Operator)) != 0)
 633                                                 continue;
 634
 635                                         if (!name_entry.IsAccessible (InternalType.FakeInternalType))
 636                                                 continue;
 637
 638                                         if (name == null || name_entry.Name.StartsWith (name)) {
 639                                                 matches.Add (name_entry);
 640                                         }
 641                                 }
 642                         }
 643
 644                         return matches;
 645                 }
 646
 647                 //
 648                 // Returns members of @iface only, base members are ignored
 649                 //
 650                 public static IList<MethodSpec> GetInterfaceMethods (TypeSpec iface)
 651                 {
 652                         //
 653                         // MemberCache flatten interfaces, therefore in cases like this one
 654                         //
 655                         // interface IA : IB {}
 656                         // interface IB { void Foo () }
 657                         //
 658                         // we would return Foo inside IA which is not expected in this case
 659                         //
 660                         var methods = new List<MethodSpec> ();
 661                         foreach (var entry in iface.MemberCache.member_hash.Values) {
 662                                 foreach (var name_entry in entry) {
 663                                         if (iface == name_entry.DeclaringType) {
 664                                                 if (name_entry.Kind == MemberKind.Method) {
 665                                                         methods.Add ((MethodSpec) name_entry);
 666                                                 }
 667                                         }
 668                                 }
 669                         }
 670
 671                         return methods;
 672                 }
 673
 674                 //
 675                 // Returns all not implememted abstract members inside abstract type
 676                 // NOTE: Returned list is shared and must not be modified
 677                 //
 678                 public static IList<MethodSpec> GetNotImplementedAbstractMethods (TypeSpec type)
 679                 {
 680                         if (type.MemberCache.missing_abstract != null)
 681                                 return type.MemberCache.missing_abstract;
 682
 683                         var abstract_methods = new List<MethodSpec> ();
 684                         List<TypeSpec> hierarchy = null;
 685
 686                         //
 687                         // Stage 1: top-to-bottom scan for abstract members
 688                         //
 689                         var abstract_type = type;
 690                         while (true) {
 691                                 foreach (var entry in abstract_type.MemberCache.member_hash) {
 692                                         foreach (var name_entry in entry.Value) {
 693                                                 if ((name_entry.Modifiers & Modifiers.ABSTRACT) == 0)
 694                                                         continue;
 695
 696                                                 if (name_entry.Kind != MemberKind.Method)
 697                                                         continue;
 698
 699                                                 abstract_methods.Add ((MethodSpec) name_entry);
 700                                         }
 701                                 }
 702
 703                                 var base_type = abstract_type.BaseType;
 704                                 if (!base_type.IsAbstract)
 705                                         break;
 706
 707                                 if (hierarchy == null)
 708                                         hierarchy = new List<TypeSpec> ();
 709
 710                                 hierarchy.Add (abstract_type);
 711                                 abstract_type = base_type;
 712                         }
 713
 714                         int not_implemented_count = abstract_methods.Count;
 715                         if (not_implemented_count == 0 || hierarchy == null) {
 716                                 type.MemberCache.missing_abstract = abstract_methods;
 717                                 return type.MemberCache.missing_abstract;
 718                         }
 719
 720                         //
 721                         // Stage 2: Remove already implemented methods
 722                         //
 723                         foreach (var type_up in hierarchy) {
 724                                 var members = type_up.MemberCache.member_hash;
 725                                 if (members.Count == 0)
 726                                         continue;
 727
 728                                 for (int i = 0; i < abstract_methods.Count; ++i) {
 729                                         var candidate = abstract_methods [i];
 730                                         if (candidate == null)
 731                                                 continue;
 732
 733                                         IList<MemberSpec> applicable;
 734                                         if (!members.TryGetValue (candidate.Name, out applicable))
 735                                                 continue;
 736
 737                                         var filter = new MemberFilter (candidate);
 738                                         foreach (var item in applicable) {
 739                                                 if ((item.Modifiers & (Modifiers.OVERRIDE | Modifiers.VIRTUAL)) == 0)
 740                                                         continue;
 741
 742                                                 if (filter.Equals (item)) {
 743                                                         --not_implemented_count;
 744                                                         abstract_methods [i] = null;
 745                                                         break;
 746                                                 }
 747                                         }
 748                                 }
 749                         }
 750
 751                         if (not_implemented_count == abstract_methods.Count) {
 752                                 type.MemberCache.missing_abstract = abstract_methods;
 753                                 return type.MemberCache.missing_abstract;
 754                         }
 755
 756                         var not_implemented = new MethodSpec[not_implemented_count];
 757                         int counter = 0;
 758                         foreach (var m in abstract_methods) {
 759                                 if (m == null)
 760                                         continue;
 761
 762                                 not_implemented[counter++] = m;
 763                         }
 764
 765                         type.MemberCache.missing_abstract = not_implemented;
 766                         return type.MemberCache.missing_abstract;
 767                 }
 768
 769                 static string GetLookupName (MemberSpec ms)
 770                 {
 771                         if (ms.Kind == MemberKind.Indexer)
 772                                 return IndexerNameAlias;
 773
 774                         if (ms.Kind == MemberKind.Constructor) {
 775                                 if (ms.IsStatic)
 776                                         return ConstructorInfo.TypeConstructorName;
 777
 778                                 return ConstructorInfo.ConstructorName;
 779                         }
 780
 781                         return ms.Name;
 782                 }
 783
 784                 static string GetLookupName (MemberCore mc)
 785                 {
 786                         if (mc is Indexer)
 787                                 return IndexerNameAlias;
 788
 789                         if (mc is Constructor)
 790                                 return ConstructorInfo.ConstructorName;
 791
 792                         return mc.MemberName.Name;
 793                 }
 794
 795                 //
 796                 // Returns all operators declared on container and its base types (until declaredOnly is used)
 797                 //
 798                 public static IList<MemberSpec> GetUserOperator (TypeSpec container, Operator.OpType op, bool declaredOnly)
 799                 {
 800                         IList<MemberSpec> found = null;
 801
 802                         IList<MemberSpec> applicable;
 803                         do {
 804                                 var mc = container.MemberCache;
 805
 806                                 if (((op == Operator.OpType.Implicit || op == Operator.OpType.Explicit) && (mc.state & StateFlags.HasConversionOperator) != 0) ||
 807                                          (mc.state & StateFlags.HasUserOperator) != 0) {
 808
 809                                         if (mc.member_hash.TryGetValue (Operator.GetMetadataName (op), out applicable)) {
 810                                                 int match_count = 0;
 811                                                 for (int i = 0; i < applicable.Count; ++i) {
 812                                                         if (applicable[i].Kind == MemberKind.Operator) {
 813                                                                 ++match_count;
 814                                                                 continue;
 815                                                         }
 816
 817                                                         // Handles very rare case where a method exists with same name as operator (op_xxxx)
 818                                                         if (found == null) {
 819                                                                 found = new List<MemberSpec> ();
 820                                                                 found.Add (applicable [i]);
 821                                                         } else {
 822                                                                 var prev = found as List<MemberSpec>;
 823                                                                 if (prev == null) {
 824                                                                         prev = new List<MemberSpec> (found.Count + 1);
 825                                                                         prev.AddRange (found);
 826                                                                 }
 827
 828                                                                 prev.Add (applicable[i]);
 829                                                         }
 830                                                 }
 831
 832                                                 if (match_count > 0 && match_count == applicable.Count) {
 833                                                         if (found == null) {
 834                                                                 found = applicable;
 835                                                         } else {
 836                                                                 var merged = found as List<MemberSpec>;
 837                                                                 if (merged == null) {
 838                                                                         merged = new List<MemberSpec> (found.Count + applicable.Count);
 839                                                                         merged.AddRange (found);
 840                                                                         found = merged;
 841                                                                 }
 842
 843                                                                 merged.AddRange (applicable);
 844                                                         }
 845                                                 }
 846                                         }
 847                                 }
 848
 849                                 // BaseType call can be expensive
 850                                 if (declaredOnly)
 851                                         break;
 852
 853                                 container = container.BaseType;
 854                         } while (container != null);
 855
 856                         return found;
 857                 }
 858
 859                 //
 860                 // Inflates all member cache nested types
 861                 //
 862                 public void InflateTypes (MemberCache inflated_cache, TypeParameterInflator inflator)
 863                 {
 864                         foreach (var item in member_hash) {
 865                                 IList<MemberSpec> inflated_members = null;
 866                                 for (int i = 0; i < item.Value.Count; ++i ) {
 867                                         var member = item.Value[i];
 868
 869                                         // FIXME: When inflating members refering nested types before they are inflated
 870                                         if (member == null)
 871                                                 continue;
 872
 873                                         if ((member.Kind & MemberKind.NestedMask) != 0 &&
 874                                                 (member.Modifiers & Modifiers.COMPILER_GENERATED) == 0) {
 875                                                 if (inflated_members == null) {
 876                                                         inflated_members = new MemberSpec[item.Value.Count];
 877                                                         inflated_cache.member_hash.Add (item.Key, inflated_members);
 878                                                 }
 879
 880                                                 inflated_members [i] = member.InflateMember (inflator);
 881                                         }
 882                                 }
 883                         }
 884                 }
 885
 886                 //
 887                 // Inflates all open type members, requires InflateTypes to be called before
 888                 //
 889                 public void InflateMembers (MemberCache cacheToInflate, TypeSpec inflatedType, TypeParameterInflator inflator)
 890                 {
 891                         var inflated_member_hash = cacheToInflate.member_hash;
 892                         Dictionary<MethodSpec, MethodSpec> accessor_relation = null;
 893                         List<MemberSpec> accessor_members = null;
 894
 895                         // Copy member specific flags when all members were added
 896                         cacheToInflate.state = state;
 897
 898                         foreach (var item in member_hash) {
 899                                 var members = item.Value;
 900                                 IList<MemberSpec> inflated_members = null;
 901                                 for (int i = 0; i < members.Count; ++i ) {
 902                                         var member = members[i];
 903
 904                                         //
 905                                         // All nested types have been inflated earlier except for
 906                                         // compiler types which are created later and could miss InflateTypes
 907                                         //
 908                                         if ((member.Kind & MemberKind.NestedMask) != 0 &&
 909                                                 (member.Modifiers & Modifiers.COMPILER_GENERATED) == 0) {
 910                                                 if (inflated_members == null)
 911                                                         inflated_members = inflated_member_hash[item.Key];
 912
 913                                                 continue;
 914                                         }
 915
 916                                         //
 917                                         // Clone the container first
 918                                         //
 919                                         if (inflated_members == null) {
 920                                                 inflated_members = new MemberSpec [item.Value.Count];
 921                                                 inflated_member_hash.Add (item.Key, inflated_members);
 922                                         }
 923
 924                                         var local_inflator = inflator;
 925
 926                                         if (member.DeclaringType != inflatedType) {
 927                                                 //
 928                                                 // Don't inflate non generic interface members
 929                                                 // merged into generic interface
 930                                                 //
 931                                                 if (!member.DeclaringType.IsGeneric) {
 932                                                         inflated_members [i] = member;
 933                                                         continue;
 934                                                 }
 935
 936                                                 //
 937                                                 // Needed when inflating flatten interfaces. It inflates
 938                                                 // container type only, type parameters are already done
 939                                                 //
 940                                                 // Handles cases like:
 941                                                 //
 942                                                 // interface I<T> {}
 943                                                 // interface I<U, V> : I<U> {}
 944                                                 //
 945                                                 // class C: I<int, bool> {}
 946                                                 //
 947                                                 var inflated_parent = inflator.Inflate (member.DeclaringType);
 948                                                 if (inflated_parent != inflator.TypeInstance)
 949                                                         local_inflator = new TypeParameterInflator (inflator, inflated_parent);
 950                                         }
 951
 952                                         //
 953                                         // Inflate every member, its parent is now different
 954                                         //
 955                                         var inflated = member.InflateMember (local_inflator);
 956                                         inflated_members [i] = inflated;
 957
 958                                         if (member is PropertySpec || member is EventSpec) {
 959                                                 if (accessor_members == null)
 960                                                         accessor_members = new List<MemberSpec> ();
 961
 962                                                 accessor_members.Add (inflated);
 963                                                 continue;
 964                                         }
 965
 966                                         if (member.IsAccessor) {
 967                                                 if (accessor_relation == null)
 968                                                         accessor_relation = new Dictionary<MethodSpec, MethodSpec> ();
 969                                                 accessor_relation.Add ((MethodSpec) member, (MethodSpec) inflated);
 970                                         }
 971                                 }
 972                         }
 973
 974                         if (accessor_members != null) {
 975                                 foreach (var member in accessor_members) {
 976                                         var prop = member as PropertySpec;
 977                                         if (prop != null) {
 978                                                 if (prop.Get != null)
 979                                                         prop.Get = accessor_relation[prop.Get];
 980                                                 if (prop.Set != null)
 981                                                         prop.Set = accessor_relation[prop.Set];
 982
 983                                                 continue;
 984                                         }
 985
 986                                         var ev = (EventSpec) member;
 987                                         ev.AccessorAdd = accessor_relation[ev.AccessorAdd];
 988                                         ev.AccessorRemove = accessor_relation[ev.AccessorRemove];
 989                                 }
 990                         }
 991                 }
 992
 993                 //
 994                 // Checks all appropriate container members for CLS compliance
 995                 //
 996                 public void VerifyClsCompliance (TypeSpec container, Report report)
 997                 {
 998                         if (locase_members != null)
 999                                 return;
1000
1001                         if (container.BaseType == null) {
1002                                 locase_members = new Dictionary<string, MemberSpec[]> (member_hash.Count); // StringComparer.OrdinalIgnoreCase);
1003                         } else {
1004                                 container.BaseType.MemberCache.VerifyClsCompliance (container.BaseType, report);
1005                                 locase_members = new Dictionary<string, MemberSpec[]> (container.BaseType.MemberCache.locase_members); //, StringComparer.OrdinalIgnoreCase);
1006                         }
1007
1008                         var is_imported_type = container.MemberDefinition.IsImported;
1009                         foreach (var entry in container.MemberCache.member_hash) {
1010                                 for (int i = 0; i < entry.Value.Count; ++i ) {
1011                                         var name_entry = entry.Value[i];
1012                                         if ((name_entry.Modifiers & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
1013                                                 continue;
1014
1015                                         if ((name_entry.Modifiers & (Modifiers.OVERRIDE | Modifiers.COMPILER_GENERATED)) != 0)
1016                                                 continue;
1017
1018                                         if ((name_entry.Kind & MemberKind.MaskType) == 0)
1019                                                 continue;
1020
1021                                         if (name_entry.MemberDefinition.IsNotCLSCompliant ())
1022                                             continue;
1023
1024                                         IParametersMember p_a = name_entry as IParametersMember;
1025                                         if (p_a != null && !name_entry.IsAccessor) {
1026                                                 if (!is_imported_type) {
1027                                                         var p_a_pd = p_a.Parameters;
1028                                                         for (int ii = i + 1; ii < entry.Value.Count; ++ii) {
1029                                                                 var checked_entry = entry.Value[ii];
1030                                                                 IParametersMember p_b = checked_entry as IParametersMember;
1031                                                                 if (p_b == null)
1032                                                                         continue;
1033
1034                                                                 if (p_a_pd.Count != p_b.Parameters.Count)
1035                                                                         continue;
1036
1037                                                                 if (checked_entry.IsAccessor)
1038                                                                         continue;
1039
1040                                                                 var res = ParametersCompiled.IsSameClsSignature (p_a.Parameters, p_b.Parameters);
1041                                                                 if (res != 0) {
1042                                                                         var last = GetLaterDefinedMember (checked_entry, name_entry);
1043                                                                         if (last == checked_entry.MemberDefinition) {
1044                                                                                 report.SymbolRelatedToPreviousError (name_entry);
1045                                                                         } else {
1046                                                                                 report.SymbolRelatedToPreviousError (checked_entry);
1047                                                                         }
1048
1049                                                                         if ((res & 1) != 0) {
1050                                                                                 report.Warning (3006, 1, last.Location,
1051                                                                                                 "Overloaded method `{0}' differing only in ref or out, or in array rank, is not CLS-compliant",
1052                                                                                                 name_entry.GetSignatureForError ());
1053                                                                         }
1054
1055                                                                         if ((res & 2) != 0) {
1056                                                                                 report.Warning (3007, 1, last.Location,
1057                                                                                         "Overloaded method `{0}' differing only by unnamed array types is not CLS-compliant",
1058                                                                                         name_entry.GetSignatureForError ());
1059                                                                         }
1060                                                                 }
1061                                                         }
1062                                                 }
1063                                         }
1064
1065                                         if (i > 0 || name_entry.Kind == MemberKind.Constructor || name_entry.Kind == MemberKind.Indexer)
1066                                                 continue;
1067
1068                                         var name_entry_locase = name_entry.Name.ToLowerInvariant ();
1069
1070                                         MemberSpec[] found;
1071                                         if (!locase_members.TryGetValue (name_entry_locase, out found)) {
1072                                                 found = new MemberSpec[] { name_entry };
1073                                                 locase_members.Add (name_entry_locase, found);
1074                                         } else {
1075                                                 bool same_names_only = true;
1076                                                 foreach (var f in found) {
1077                                                         if (f.Name == name_entry.Name)
1078                                                                 continue;
1079
1080 //                                                      if (f.IsAccessor && name_entry.IsAccessor)
1081 //                                                              continue;
1082
1083                                                         same_names_only = false;
1084                                                         if (!is_imported_type) {
1085                                                                 var last = GetLaterDefinedMember (f, name_entry);
1086                                                                 if (last == f.MemberDefinition) {
1087                                                                         report.SymbolRelatedToPreviousError (name_entry);
1088                                                                 } else {
1089                                                                         report.SymbolRelatedToPreviousError (f);
1090                                                                 }
1091
1092                                                                 report.Warning (3005, 1, last.Location,
1093                                                                         "Identifier `{0}' differing only in case is not CLS-compliant", last.GetSignatureForError ());
1094                                                         }
1095                                                 }
1096
1097                                                 if (!same_names_only) {
1098                                                         Array.Resize (ref found, found.Length + 1);
1099                                                         found[found.Length - 1] = name_entry;
1100                                                         locase_members[name_entry_locase] = found;
1101                                                 }
1102                                         }
1103                                 }
1104                         }
1105                 }
1106
1107                 //
1108                 // Local report helper to issue correctly ordered members stored in hashtable
1109                 //
1110                 static MemberCore GetLaterDefinedMember (MemberSpec a, MemberSpec b)
1111                 {
1112                         var mc_a = a.MemberDefinition as MemberCore;
1113                         var mc_b = b.MemberDefinition as MemberCore;
1114                         if (mc_a == null)
1115                                 return mc_b;
1116
1117                         if (mc_b == null)
1118                                 return mc_a;
1119
1120                         if (mc_a.Location.File != mc_a.Location.File)
1121                                 return mc_b;
1122
1123                         return mc_b.Location.Row > mc_a.Location.Row ? mc_b : mc_a;
1124                 }
1125
1126                 public bool CheckExistingMembersOverloads (MemberCore member, AParametersCollection parameters)
1127                 {
1128                         var name = GetLookupName (member);
1129                         var imb = member as InterfaceMemberBase;
1130                         if (imb != null && imb.IsExplicitImpl) {
1131                                 name = imb.GetFullName (name);
1132                         }
1133
1134                         return CheckExistingMembersOverloads (member, name, parameters);
1135                 }
1136
1137                 public bool CheckExistingMembersOverloads (MemberCore member, string name, AParametersCollection parameters)
1138                 {
1139                         IList<MemberSpec> entries;
1140                         if (!member_hash.TryGetValue (name, out entries))
1141                                 return false;
1142
1143                         var Report = member.Compiler.Report;
1144
1145                         int method_param_count = parameters.Count;
1146                         for (int i = entries.Count - 1; i >= 0; --i) {
1147                                 var ce = entries[i];
1148                                 var pm = ce as IParametersMember;
1149                                 var pd = pm == null ? ParametersCompiled.EmptyReadOnlyParameters : pm.Parameters;
1150                                 if (pd.Count != method_param_count)
1151                                         continue;
1152
1153                                 if (ce.Arity != member.MemberName.Arity)
1154                                         continue;
1155
1156                                 // Ignore merged interface members
1157                                 if (member.Parent.PartialContainer != ce.DeclaringType.MemberDefinition)
1158                                         continue;
1159
1160                                 var p_types = pd.Types;
1161                                 if (method_param_count > 0) {
1162                                         int ii = method_param_count - 1;
1163                                         TypeSpec type_a, type_b;
1164                                         do {
1165                                                 type_a = parameters.Types [ii];
1166                                                 type_b = p_types [ii];
1167
1168                                                 if ((pd.FixedParameters [ii].ModFlags & Parameter.Modifier.ISBYREF) !=
1169                                                         (parameters.FixedParameters [ii].ModFlags & Parameter.Modifier.ISBYREF))
1170                                                         break;
1171
1172                                         } while (TypeSpecComparer.Override.IsEqual (type_a, type_b) && ii-- != 0);
1173
1174                                         if (ii >= 0)
1175                                                 continue;
1176
1177                                         //
1178                                         // Operators can differ in return type only
1179                                         //
1180                                         if (member is Operator && ce.Kind == MemberKind.Operator && ((MethodSpec) ce).ReturnType != ((Operator) member).ReturnType)
1181                                                 continue;
1182
1183                                         //
1184                                         // Report difference in parameter modifiers only
1185                                         //
1186                                         if (pd != null && member is MethodCore) {
1187                                                 ii = method_param_count;
1188                                                 while (ii-- != 0 && parameters.FixedParameters[ii].ModFlags == pd.FixedParameters[ii].ModFlags &&
1189                                                         parameters.ExtensionMethodType == pd.ExtensionMethodType) ;
1190
1191                                                 if (ii >= 0) {
1192                                                         var mc = ce as MethodSpec;
1193                                                         member.Compiler.Report.SymbolRelatedToPreviousError (ce);
1194                                                         if ((member.ModFlags & Modifiers.PARTIAL) != 0 && (mc.Modifiers & Modifiers.PARTIAL) != 0) {
1195                                                                 if (parameters.HasParams || pd.HasParams) {
1196                                                                         Report.Error (758, member.Location,
1197                                                                                 "A partial method declaration and partial method implementation cannot differ on use of `params' modifier");
1198                                                                 } else {
1199                                                                         Report.Error (755, member.Location,
1200                                                                                 "A partial method declaration and partial method implementation must be both an extension method or neither");
1201                                                                 }
1202                                                         } else if (member is Constructor) {
1203                                                                 Report.Error (851, member.Location,
1204                                                                         "Overloaded contructor `{0}' cannot differ on use of parameter modifiers only",
1205                                                                         member.GetSignatureForError ());
1206                                                         } else {
1207                                                                 Report.Error (663, member.Location,
1208                                                                         "Overloaded method `{0}' cannot differ on use of parameter modifiers only",
1209                                                                         member.GetSignatureForError ());
1210                                                         }
1211                                                         return false;
1212                                                 }
1213                                         }
1214                                 }
1215
1216                                 if ((ce.Kind & MemberKind.Method) != 0) {
1217                                         Method method_a = member as Method;
1218                                         Method method_b = ce.MemberDefinition as Method;
1219                                         if (method_a != null && method_b != null && (method_a.ModFlags & method_b.ModFlags & Modifiers.PARTIAL) != 0) {
1220                                                 const Modifiers partial_modifiers = Modifiers.STATIC | Modifiers.UNSAFE;
1221                                                 if (method_a.IsPartialDefinition == method_b.IsPartialImplementation) {
1222                                                         if ((method_a.ModFlags & partial_modifiers) == (method_b.ModFlags & partial_modifiers) ||
1223                                                                 method_a.Parent.IsUnsafe && method_b.Parent.IsUnsafe) {
1224                                                                 if (method_a.IsPartialImplementation) {
1225                                                                         method_a.SetPartialDefinition (method_b);
1226                                                                         if (entries.Count == 1)
1227                                                                                 member_hash.Remove (name);
1228                                                                         else
1229                                                                                 entries.RemoveAt (i);
1230                                                                 } else {
1231                                                                         method_b.SetPartialDefinition (method_a);
1232                                                                         method_a.caching_flags |= MemberCore.Flags.PartialDefinitionExists;
1233                                                                 }
1234                                                                 continue;
1235                                                         }
1236
1237                                                         if (method_a.IsStatic != method_b.IsStatic) {
1238                                                                 Report.SymbolRelatedToPreviousError (ce);
1239                                                                 Report.Error (763, member.Location,
1240                                                                         "A partial method declaration and partial method implementation must be both `static' or neither");
1241                                                         }
1242
1243                                                         Report.SymbolRelatedToPreviousError (ce);
1244                                                         Report.Error (764, member.Location,
1245                                                                 "A partial method declaration and partial method implementation must be both `unsafe' or neither");
1246                                                         return false;
1247                                                 }
1248
1249                                                 Report.SymbolRelatedToPreviousError (ce);
1250                                                 if (method_a.IsPartialDefinition) {
1251                                                         Report.Error (756, member.Location, "A partial method `{0}' declaration is already defined",
1252                                                                 member.GetSignatureForError ());
1253                                                 }
1254
1255                                                 Report.Error (757, member.Location, "A partial method `{0}' implementation is already defined",
1256                                                         member.GetSignatureForError ());
1257                                                 return false;
1258                                         }
1259
1260                                         Report.SymbolRelatedToPreviousError (ce);
1261
1262                                         bool is_reserved_a = member is AbstractPropertyEventMethod || member is Operator;
1263                                         bool is_reserved_b = ((MethodSpec) ce).IsReservedMethod;
1264
1265                                         if (is_reserved_a || is_reserved_b) {
1266                                                 Report.Error (82, member.Location, "A member `{0}' is already reserved",
1267                                                         is_reserved_a ?
1268                                                         ce.GetSignatureForError () :
1269                                                         member.GetSignatureForError ());
1270                                                 return false;
1271                                         }
1272                                 } else {
1273                                         Report.SymbolRelatedToPreviousError (ce);
1274                                 }
1275
1276                                 if (member is Operator && ce.Kind == MemberKind.Operator) {
1277                                         Report.Error (557, member.Location, "Duplicate user-defined conversion in type `{0}'",
1278                                                 member.Parent.GetSignatureForError ());
1279                                         return false;
1280                                 }
1281
1282                                 Report.Error (111, member.Location,
1283                                         "A member `{0}' is already defined. Rename this member or use different parameter types",
1284                                         member.GetSignatureForError ());
1285                                 return false;
1286                         }
1287
1288                         return true;
1289                 }
1290         }
1291 }