mcs/mcs/dynamic.cs

   1 //
   2 // dynamic.cs: support for dynamic expressions
   3 //
   4 // Authors: Marek Safar (marek.safar@gmail.com)
   5 //
   6 // Dual licensed under the terms of the MIT X11 or GNU GPL
   7 //
   8 // Copyright 2009 Novell, Inc
   9 // Copyright 2011 Xamarin Inc.
  10 //
  11
  12 using System;
  13 using System.Linq;
  14 using SLE = System.Linq.Expressions;
  15 using System.Dynamic;
  16 #if STATIC
  17 using IKVM.Reflection.Emit;
  18 #else
  19 using System.Reflection.Emit;
  20 #endif
  21
  22 namespace Mono.CSharp
  23 {
  24         //
  25         // A copy of Microsoft.CSharp/Microsoft.CSharp.RuntimeBinder/CSharpBinderFlags.cs
  26         // has to be kept in sync
  27         //
  28         [Flags]
  29         public enum CSharpBinderFlags
  30         {
  31                 None = 0,
  32                 CheckedContext = 1,
  33                 InvokeSimpleName = 1 << 1,
  34                 InvokeSpecialName = 1 << 2,
  35                 BinaryOperationLogical = 1 << 3,
  36                 ConvertExplicit = 1 << 4,
  37                 ConvertArrayIndex = 1 << 5,
  38                 ResultIndexed = 1 << 6,
  39                 ValueFromCompoundAssignment = 1 << 7,
  40                 ResultDiscarded = 1 << 8
  41         }
  42
  43         //
  44         // Type expression with internal dynamic type symbol
  45         //
  46         class DynamicTypeExpr : TypeExpr
  47         {
  48                 public DynamicTypeExpr (Location loc)
  49                 {
  50                         this.loc = loc;
  51                 }
  52
  53                 public override TypeSpec ResolveAsType (IMemberContext ec, bool allowUnboundTypeArguments)
  54                 {
  55                         eclass = ExprClass.Type;
  56                         type = ec.Module.Compiler.BuiltinTypes.Dynamic;
  57                         return type;
  58                 }
  59         }
  60
  61         #region Dynamic runtime binder expressions
  62
  63         //
  64         // Expression created from runtime dynamic object value by dynamic binder
  65         //
  66         public class RuntimeValueExpression : Expression, IDynamicAssign, IMemoryLocation
  67         {
  68
  69                 readonly DynamicMetaObject obj;
  70
  71                 public RuntimeValueExpression (DynamicMetaObject obj, TypeSpec type)
  72                 {
  73                         this.obj = obj;
  74                         this.type = type;
  75                         this.eclass = ExprClass.Variable;
  76                 }
  77
  78                 #region Properties
  79
  80                 public bool IsSuggestionOnly { get; set; }
  81
  82                 public DynamicMetaObject MetaObject {
  83                         get { return obj; }
  84                 }
  85
  86                 #endregion
  87
  88                 public void AddressOf (EmitContext ec, AddressOp mode)
  89                 {
  90                         throw new NotImplementedException ();
  91                 }
  92
  93                 public override bool ContainsEmitWithAwait ()
  94                 {
  95                         throw new NotSupportedException ();
  96                 }
  97
  98                 public override Expression CreateExpressionTree (ResolveContext ec)
  99                 {
 100                         throw new NotSupportedException ();
 101                 }
 102
 103                 protected override Expression DoResolve (ResolveContext ec)
 104                 {
 105                         return this;
 106                 }
 107
 108                 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
 109                 {
 110                         return this;
 111                 }
 112
 113                 public override void Emit (EmitContext ec)
 114                 {
 115                         throw new NotImplementedException ();
 116                 }
 117
 118                 #region IAssignMethod Members
 119
 120                 public void Emit (EmitContext ec, bool leave_copy)
 121                 {
 122                         throw new NotImplementedException ();
 123                 }
 124
 125                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
 126                 {
 127                         throw new NotImplementedException ();
 128                 }
 129
 130                 #endregion
 131
 132                 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
 133                 {
 134                         return obj.Expression;
 135                 }
 136
 137                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 138                 {
 139 #if STATIC
 140                         return base.MakeExpression (ctx);
 141 #else
 142
 143                                 if (type.IsStruct && !obj.Expression.Type.IsValueType)
 144                                         return SLE.Expression.Unbox (obj.Expression, type.GetMetaInfo ());
 145
 146                                 if (obj.Expression.NodeType == SLE.ExpressionType.Parameter) {
 147                                         if (((SLE.ParameterExpression) obj.Expression).IsByRef)
 148                                                 return obj.Expression;
 149                                 }
 150
 151                                 return SLE.Expression.Convert (obj.Expression, type.GetMetaInfo ());
 152 #endif
 153                 }
 154         }
 155
 156         //
 157         // Wraps runtime dynamic expression into expected type. Needed
 158         // to satify expected type check by dynamic binder and no conversion
 159         // is required (ResultDiscarded).
 160         //
 161         public class DynamicResultCast : ShimExpression
 162         {
 163                 public DynamicResultCast (TypeSpec type, Expression expr)
 164                         : base (expr)
 165                 {
 166                         this.type = type;
 167                 }
 168
 169                 protected override Expression DoResolve (ResolveContext ec)
 170                 {
 171                         expr = expr.Resolve (ec);
 172                         eclass = ExprClass.Value;
 173                         return this;
 174                 }
 175
 176                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 177                 {
 178 #if STATIC
 179                         return base.MakeExpression (ctx);
 180 #else
 181                         return SLE.Expression.Block (expr.MakeExpression (ctx), SLE.Expression.Default (type.GetMetaInfo ()));
 182 #endif
 183                 }
 184         }
 185
 186         #endregion
 187
 188         //
 189         // Creates dynamic binder expression
 190         //
 191         interface IDynamicBinder
 192         {
 193                 Expression CreateCallSiteBinder (ResolveContext ec, Arguments args);
 194         }
 195
 196         //
 197         // Extends standard assignment interface for expressions
 198         // supported by dynamic resolver
 199         //
 200         interface IDynamicAssign : IAssignMethod
 201         {
 202                 SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
 203         }
 204
 205         //
 206         // Base dynamic expression statement creator
 207         //
 208         class DynamicExpressionStatement : ExpressionStatement
 209         {
 210                 //
 211                 // Binder flag dynamic constant, the value is combination of
 212                 // flags known at resolve stage and flags known only at emit
 213                 // stage
 214                 //
 215                 protected class BinderFlags : EnumConstant
 216                 {
 217                         readonly DynamicExpressionStatement statement;
 218                         readonly CSharpBinderFlags flags;
 219
 220                         public BinderFlags (CSharpBinderFlags flags, DynamicExpressionStatement statement)
 221                                 : base (statement.loc)
 222                         {
 223                                 this.flags = flags;
 224                                 this.statement = statement;
 225                                 eclass = 0;
 226                         }
 227
 228                         protected override Expression DoResolve (ResolveContext ec)
 229                         {
 230                                 Child = new IntConstant (ec.BuiltinTypes, (int) (flags | statement.flags), statement.loc);
 231
 232                                 type = ec.Module.PredefinedTypes.BinderFlags.Resolve ();
 233                                 eclass = Child.eclass;
 234                                 return this;
 235                         }
 236                 }
 237
 238                 readonly Arguments arguments;
 239                 protected IDynamicBinder binder;
 240                 protected Expression binder_expr;
 241
 242                 // Used by BinderFlags
 243                 protected CSharpBinderFlags flags;
 244
 245                 TypeSpec binder_type;
 246                 TypeParameters context_mvars;
 247
 248                 public DynamicExpressionStatement (IDynamicBinder binder, Arguments args, Location loc)
 249                 {
 250                         this.binder = binder;
 251                         this.arguments = args;
 252                         this.loc = loc;
 253                 }
 254
 255                 public Arguments Arguments {
 256                         get {
 257                                 return arguments;
 258                         }
 259                 }
 260
 261                 public override bool ContainsEmitWithAwait ()
 262                 {
 263                         return arguments.ContainsEmitWithAwait ();
 264                 }
 265
 266                 public override Expression CreateExpressionTree (ResolveContext ec)
 267                 {
 268                         ec.Report.Error (1963, loc, "An expression tree cannot contain a dynamic operation");
 269                         return null;
 270                 }
 271
 272                 protected override Expression DoResolve (ResolveContext rc)
 273                 {
 274                         if (DoResolveCore (rc))
 275                                 binder_expr = binder.CreateCallSiteBinder (rc, arguments);
 276
 277                         return this;
 278                 }
 279
 280                 protected bool DoResolveCore (ResolveContext rc)
 281                 {
 282                         foreach (var arg in arguments) {
 283                                 if (arg.Type == InternalType.VarOutType) {
 284                                         // Should be special error message about dynamic dispatch
 285                                         rc.Report.Error (8197, arg.Expr.Location, "Cannot infer the type of implicitly-typed out variable `{0}'", ((DeclarationExpression) arg.Expr).Variable.Name);
 286                                 }
 287                         }
 288
 289                         if (rc.CurrentTypeParameters != null && rc.CurrentTypeParameters[0].IsMethodTypeParameter)
 290                                 context_mvars = rc.CurrentTypeParameters;
 291
 292                         int errors = rc.Report.Errors;
 293                         var pt = rc.Module.PredefinedTypes;
 294
 295                         binder_type = pt.Binder.Resolve ();
 296                         pt.CallSite.Resolve ();
 297                         pt.CallSiteGeneric.Resolve ();
 298
 299                         eclass = ExprClass.Value;
 300
 301                         if (type == null)
 302                                 type = rc.BuiltinTypes.Dynamic;
 303
 304                         if (rc.Report.Errors == errors)
 305                                 return true;
 306
 307                         rc.Report.Error (1969, loc,
 308                                 "Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference");
 309                         return false;
 310                 }
 311
 312                 public override void Emit (EmitContext ec)
 313                 {
 314                         EmitCall (ec, binder_expr, arguments,  false);
 315                 }
 316
 317                 public override void EmitStatement (EmitContext ec)
 318                 {
 319                         EmitCall (ec, binder_expr, arguments, true);
 320                 }
 321
 322                 protected void EmitConditionalAccess (EmitContext ec)
 323                 {
 324                         var a_expr = arguments [0].Expr;
 325
 326                         var des = a_expr as DynamicExpressionStatement;
 327                         if (des != null) {
 328                                 des.EmitConditionalAccess (ec);
 329                         }
 330
 331                         if (HasConditionalAccess ()) {
 332                                 var NullOperatorLabel = ec.DefineLabel ();
 333
 334                                 if (ExpressionAnalyzer.IsInexpensiveLoad (a_expr)) {
 335                                         a_expr.Emit (ec);
 336                                 } else {
 337                                         var lt = new LocalTemporary (a_expr.Type);
 338                                         lt.EmitAssign (ec, a_expr, true, false);
 339
 340                                         Arguments [0].Expr = lt;
 341                                 }
 342
 343                                 ec.Emit (OpCodes.Brtrue_S, NullOperatorLabel);
 344
 345                                 if (!ec.ConditionalAccess.Statement) {
 346                                         if (ec.ConditionalAccess.Type.IsNullableType)
 347                                                 Nullable.LiftedNull.Create (ec.ConditionalAccess.Type, Location.Null).Emit (ec);
 348                                         else
 349                                                 ec.EmitNull ();
 350                                 }
 351
 352                                 ec.Emit (OpCodes.Br, ec.ConditionalAccess.EndLabel);
 353                                 ec.MarkLabel (NullOperatorLabel);
 354
 355                                 return;
 356                         }
 357
 358                         if (a_expr.HasConditionalAccess ()) {
 359                                 var lt = new LocalTemporary (a_expr.Type);
 360                                 lt.EmitAssign (ec, a_expr, false, false);
 361
 362                                 Arguments [0].Expr = lt;
 363                         }
 364                 }
 365
 366                 protected void EmitCall (EmitContext ec, Expression binder, Arguments arguments, bool isStatement)
 367                 {
 368                         //
 369                         // This method generates all internal infrastructure for a dynamic call. The
 370                         // reason why it's quite complicated is the mixture of dynamic and anonymous
 371                         // methods. Dynamic itself requires a temporary class (ContainerX) and anonymous
 372                         // methods can generate temporary storey as well (AnonStorey). Handling MVAR
 373                         // type parameters rewrite is non-trivial in such case as there are various
 374                         // combinations possible therefore the mutator is not straightforward. Secondly
 375                         // we need to keep both MVAR(possibly VAR for anon storey) and type VAR to emit
 376                         // correct Site field type and its access from EmitContext.
 377                         //
 378
 379                         int dyn_args_count = arguments == null ? 0 : arguments.Count;
 380                         int default_args = isStatement ? 1 : 2;
 381                         var module = ec.Module;
 382
 383                         bool has_ref_out_argument = false;
 384                         var targs = new TypeExpression[dyn_args_count + default_args];
 385                         targs[0] = new TypeExpression (module.PredefinedTypes.CallSite.TypeSpec, loc);
 386
 387                         TypeExpression[] targs_for_instance = null;
 388                         TypeParameterMutator mutator;
 389
 390                         var site_container = ec.CreateDynamicSite ();
 391
 392                         if (context_mvars != null) {
 393                                 TypeParameters tparam;
 394                                 TypeContainer sc = site_container;
 395                                 do {
 396                                         tparam = sc.CurrentTypeParameters;
 397                                         sc = sc.Parent;
 398                                 } while (tparam == null);
 399
 400                                 mutator = new TypeParameterMutator (context_mvars, tparam);
 401
 402                                 if (!ec.IsAnonymousStoreyMutateRequired) {
 403                                         targs_for_instance = new TypeExpression[targs.Length];
 404                                         targs_for_instance[0] = targs[0];
 405                                 }
 406                         } else {
 407                                 mutator = null;
 408                         }
 409
 410                         for (int i = 0; i < dyn_args_count; ++i) {
 411                                 Argument a = arguments[i];
 412                                 if (a.ArgType == Argument.AType.Out || a.ArgType == Argument.AType.Ref)
 413                                         has_ref_out_argument = true;
 414
 415                                 var t = a.Type;
 416
 417                                 // Convert any internal type like dynamic or null to object
 418                                 if (t.Kind == MemberKind.InternalCompilerType)
 419                                         t = ec.BuiltinTypes.Object;
 420
 421                                 if (targs_for_instance != null)
 422                                         targs_for_instance[i + 1] = new TypeExpression (t, loc);
 423
 424                                 if (mutator != null)
 425                                         t = t.Mutate (mutator);
 426
 427                                 targs[i + 1] = new TypeExpression (t, loc);
 428                         }
 429
 430                         TypeExpr del_type = null;
 431                         TypeExpr del_type_instance_access = null;
 432                         if (!has_ref_out_argument) {
 433                                 string d_name = isStatement ? "Action" : "Func";
 434
 435                                 TypeSpec te = null;
 436                                 Namespace type_ns = module.GlobalRootNamespace.GetNamespace ("System", true);
 437                                 if (type_ns != null) {
 438                                         te = type_ns.LookupType (module, d_name, dyn_args_count + default_args, LookupMode.Normal, loc);
 439                                 }
 440
 441                                 if (te != null) {
 442                                         if (!isStatement) {
 443                                                 var t = type;
 444                                                 if (t.Kind == MemberKind.InternalCompilerType)
 445                                                         t = ec.BuiltinTypes.Object;
 446
 447                                                 if (targs_for_instance != null)
 448                                                         targs_for_instance[targs_for_instance.Length - 1] = new TypeExpression (t, loc);
 449
 450                                                 if (mutator != null)
 451                                                         t = t.Mutate (mutator);
 452
 453                                                 targs[targs.Length - 1] = new TypeExpression (t, loc);
 454                                         }
 455
 456                                         del_type = new GenericTypeExpr (te, new TypeArguments (targs), loc);
 457                                         if (targs_for_instance != null)
 458                                                 del_type_instance_access = new GenericTypeExpr (te, new TypeArguments (targs_for_instance), loc);
 459                                         else
 460                                                 del_type_instance_access = del_type;
 461                                 }
 462                         }
 463
 464                         //
 465                         // Create custom delegate when no appropriate predefined delegate has been found
 466                         //
 467                         Delegate d;
 468                         if (del_type == null) {
 469                                 TypeSpec rt = isStatement ? ec.BuiltinTypes.Void : type;
 470                                 Parameter[] p = new Parameter[dyn_args_count + 1];
 471                                 p[0] = new Parameter (targs[0], "p0", Parameter.Modifier.NONE, null, loc);
 472
 473                                 var site = ec.CreateDynamicSite ();
 474                                 int index = site.Containers == null ? 0 : site.Containers.Count;
 475
 476                                 if (mutator != null)
 477                                         rt = mutator.Mutate (rt);
 478
 479                                 for (int i = 1; i < dyn_args_count + 1; ++i) {
 480                                         p[i] = new Parameter (targs[i], "p" + i.ToString ("X"), arguments[i - 1].Modifier, null, loc);
 481                                 }
 482
 483                                 d = new Delegate (site, new TypeExpression (rt, loc),
 484                                         Modifiers.INTERNAL | Modifiers.COMPILER_GENERATED,
 485                                         new MemberName ("Container" + index.ToString ("X")),
 486                                         new ParametersCompiled (p), null);
 487
 488                                 d.CreateContainer ();
 489                                 d.DefineContainer ();
 490                                 d.Define ();
 491                                 d.PrepareEmit ();
 492
 493                                 site.AddTypeContainer (d);
 494
 495                                 //
 496                                 // Add new container to inflated site container when the
 497                                 // member cache already exists
 498                                 //
 499                                 if (site.CurrentType is InflatedTypeSpec && index > 0)
 500                                         site.CurrentType.MemberCache.AddMember (d.CurrentType);
 501
 502                                 del_type = new TypeExpression (d.CurrentType, loc);
 503                                 if (targs_for_instance != null) {
 504                                         del_type_instance_access = null;
 505                                 } else {
 506                                         del_type_instance_access = del_type;
 507                                 }
 508                         } else {
 509                                 d = null;
 510                         }
 511
 512                         var site_type_decl = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec, new TypeArguments (del_type), loc);
 513                         var field = site_container.CreateCallSiteField (site_type_decl, loc);
 514                         if (field == null)
 515                                 return;
 516
 517                         if (del_type_instance_access == null) {
 518                                 var dt = d.CurrentType.DeclaringType.MakeGenericType (module, context_mvars.Types);
 519                                 del_type_instance_access = new TypeExpression (MemberCache.GetMember (dt, d.CurrentType), loc);
 520                         }
 521
 522                         var instanceAccessExprType = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec,
 523                                 new TypeArguments (del_type_instance_access), loc);
 524
 525                         if (instanceAccessExprType.ResolveAsType (ec.MemberContext) == null)
 526                                 return;
 527
 528                         bool inflate_using_mvar = context_mvars != null && ec.IsAnonymousStoreyMutateRequired;
 529
 530                         TypeSpec gt;
 531                         if (inflate_using_mvar || context_mvars == null) {
 532                                 gt = site_container.CurrentType;
 533                         } else {
 534                                 gt = site_container.CurrentType.MakeGenericType (module, context_mvars.Types);
 535                         }
 536
 537                         // When site container already exists the inflated version has to be
 538                         // updated manually to contain newly created field
 539                         if (gt is InflatedTypeSpec && site_container.AnonymousMethodsCounter > 1) {
 540                                 var tparams = gt.MemberDefinition.TypeParametersCount > 0 ? gt.MemberDefinition.TypeParameters : TypeParameterSpec.EmptyTypes;
 541                                 var inflator = new TypeParameterInflator (module, gt, tparams, gt.TypeArguments);
 542                                 gt.MemberCache.AddMember (field.InflateMember (inflator));
 543                         }
 544
 545                         FieldExpr site_field_expr = new FieldExpr (MemberCache.GetMember (gt, field), loc);
 546
 547                         BlockContext bc = new BlockContext (ec.MemberContext, null, ec.BuiltinTypes.Void);
 548
 549                         Arguments args = new Arguments (1);
 550                         args.Add (new Argument (binder));
 551                         StatementExpression s = new StatementExpression (new SimpleAssign (site_field_expr, new Invocation (new MemberAccess (instanceAccessExprType, "Create"), args)));
 552
 553                         using (ec.With (BuilderContext.Options.OmitDebugInfo, true)) {
 554
 555                                 var conditionalAccessReceiver = IsConditionalAccessReceiver;
 556                                 var ca = ec.ConditionalAccess;
 557
 558                                 if (conditionalAccessReceiver) {
 559                                         ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ()) {
 560                                                 Statement = isStatement
 561                                         };
 562
 563                                         //
 564                                         // Emit conditional access expressions before dynamic call
 565                                         // is initialized. It pushes site_field_expr on stack before
 566                                         // the actual instance argument is emited which would cause
 567                                         // jump from non-empty stack.
 568                                         //
 569                                         EmitConditionalAccess (ec);
 570                                 }
 571
 572                                 if (s.Resolve (bc)) {
 573                                         Statement init = new If (new Binary (Binary.Operator.Equality, site_field_expr, new NullLiteral (loc)), s, loc);
 574                                         init.Emit (ec);
 575                                 }
 576
 577                                 args = new Arguments (1 + dyn_args_count);
 578                                 args.Add (new Argument (site_field_expr));
 579                                 if (arguments != null) {
 580                                         int arg_pos = 1;
 581                                         foreach (Argument a in arguments) {
 582                                                 if (a is NamedArgument) {
 583                                                         // Name is not valid in this context
 584                                                         args.Add (new Argument (a.Expr, a.ArgType));
 585                                                 } else {
 586                                                         args.Add (a);
 587                                                 }
 588
 589                                                 if (inflate_using_mvar && a.Type != targs[arg_pos].Type)
 590                                                         a.Expr.Type = targs[arg_pos].Type;
 591
 592                                                 ++arg_pos;
 593                                         }
 594                                 }
 595
 596                                 var target = new DelegateInvocation (new MemberAccess (site_field_expr, "Target", loc).Resolve (bc), args, false, loc).Resolve (bc);
 597                                 if (target != null) {
 598                                         target.Emit (ec);
 599                                 }
 600
 601                                 if (conditionalAccessReceiver) {
 602                                         ec.CloseConditionalAccess (!isStatement && type.IsNullableType ? type : null);
 603                                         ec.ConditionalAccess = ca;
 604                                 }
 605                         }
 606                 }
 607
 608                 public override void FlowAnalysis (FlowAnalysisContext fc)
 609                 {
 610                         arguments.FlowAnalysis (fc);
 611                 }
 612
 613                 public static MemberAccess GetBinderNamespace (Location loc)
 614                 {
 615                         return new MemberAccess (new MemberAccess (
 616                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "Microsoft", loc), "CSharp", loc), "RuntimeBinder", loc);
 617                 }
 618
 619                 protected MemberAccess GetBinder (string name, Location loc)
 620                 {
 621                         return new MemberAccess (new TypeExpression (binder_type, loc), name, loc);
 622                 }
 623
 624                 protected virtual bool IsConditionalAccessReceiver {
 625                         get {
 626                                 return false;
 627                         }
 628                 }
 629         }
 630
 631         //
 632         // Dynamic member access compound assignment for events
 633         //
 634         class DynamicEventCompoundAssign : ExpressionStatement
 635         {
 636                 class IsEvent : DynamicExpressionStatement, IDynamicBinder
 637                 {
 638                         string name;
 639
 640                         public IsEvent (string name, Arguments args, Location loc)
 641                                 : base (null, args, loc)
 642                         {
 643                                 this.name = name;
 644                                 binder = this;
 645                         }
 646
 647                         public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 648                         {
 649                                 type = ec.BuiltinTypes.Bool;
 650
 651                                 Arguments binder_args = new Arguments (3);
 652
 653                                 binder_args.Add (new Argument (new BinderFlags (0, this)));
 654                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
 655                                 binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 656
 657                                 return new Invocation (GetBinder ("IsEvent", loc), binder_args);
 658                         }
 659                 }
 660
 661                 Expression condition;
 662                 ExpressionStatement invoke, assign;
 663
 664                 public DynamicEventCompoundAssign (string name, Arguments args, ExpressionStatement assignment, ExpressionStatement invoke, Location loc)
 665                 {
 666                         condition = new IsEvent (name, args, loc);
 667                         this.invoke = invoke;
 668                         this.assign = assignment;
 669                         this.loc = loc;
 670                 }
 671
 672                 public override Expression CreateExpressionTree (ResolveContext ec)
 673                 {
 674                         return condition.CreateExpressionTree (ec);
 675                 }
 676
 677                 protected override Expression DoResolve (ResolveContext rc)
 678                 {
 679                         type = rc.BuiltinTypes.Dynamic;
 680                         eclass = ExprClass.Value;
 681                         condition = condition.Resolve (rc);
 682                         return this;
 683                 }
 684
 685                 public override void Emit (EmitContext ec)
 686                 {
 687                         var rc = new ResolveContext (ec.MemberContext);
 688                         var expr = new Conditional (new BooleanExpression (condition), invoke, assign, loc).Resolve (rc);
 689                         expr.Emit (ec);
 690                 }
 691
 692                 public override void EmitStatement (EmitContext ec)
 693                 {
 694                         var stmt = new If (condition, new StatementExpression (invoke), new StatementExpression (assign), loc);
 695                         using (ec.With (BuilderContext.Options.OmitDebugInfo, true)) {
 696                                 stmt.Emit (ec);
 697                         }
 698                 }
 699
 700                 public override void FlowAnalysis (FlowAnalysisContext fc)
 701                 {
 702                         invoke.FlowAnalysis (fc);
 703                 }
 704         }
 705
 706         class DynamicConversion : DynamicExpressionStatement, IDynamicBinder
 707         {
 708                 public DynamicConversion (TypeSpec targetType, CSharpBinderFlags flags, Arguments args, Location loc)
 709                         : base (null, args, loc)
 710                 {
 711                         type = targetType;
 712                         base.flags = flags;
 713                         base.binder = this;
 714                 }
 715
 716                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 717                 {
 718                         Arguments binder_args = new Arguments (3);
 719
 720                         flags |= ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
 721
 722                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 723                         binder_args.Add (new Argument (new TypeOf (type, loc)));
 724                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 725                         return new Invocation (GetBinder ("Convert", loc), binder_args);
 726                 }
 727         }
 728
 729         class DynamicConstructorBinder : DynamicExpressionStatement, IDynamicBinder
 730         {
 731                 public DynamicConstructorBinder (TypeSpec type, Arguments args, Location loc)
 732                         : base (null, args, loc)
 733                 {
 734                         this.type = type;
 735                         base.binder = this;
 736                 }
 737
 738                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 739                 {
 740                         Arguments binder_args = new Arguments (3);
 741
 742                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 743                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 744                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 745
 746                         return new Invocation (GetBinder ("InvokeConstructor", loc), binder_args);
 747                 }
 748         }
 749
 750         class DynamicIndexBinder : DynamicMemberAssignable
 751         {
 752                 bool can_be_mutator;
 753                 readonly bool conditional_access_receiver;
 754                 readonly bool conditional_access;
 755
 756                 public DynamicIndexBinder (Arguments args, bool conditionalAccessReceiver, bool conditionalAccess, Location loc)
 757                         : base (args, loc)
 758                 {
 759                         this.conditional_access_receiver = conditionalAccessReceiver;
 760                         this.conditional_access = conditionalAccess;
 761                 }
 762
 763                 public DynamicIndexBinder (CSharpBinderFlags flags, Arguments args, Location loc)
 764                         : this (args, false, false, loc)
 765                 {
 766                         base.flags = flags;
 767                 }
 768
 769                 protected override Expression DoResolve (ResolveContext ec)
 770                 {
 771                         can_be_mutator = true;
 772                         return base.DoResolve (ec);
 773                 }
 774
 775                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 776                 {
 777                         Arguments binder_args = new Arguments (3);
 778
 779                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 780                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 781                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 782
 783                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
 784                         return new Invocation (GetBinder (isSet ? "SetIndex" : "GetIndex", loc), binder_args);
 785                 }
 786
 787                 protected override Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
 788                 {
 789                         //
 790                         // Indexer has arguments which complicates things as the setter and getter
 791                         // are called in two steps when unary mutator is used. We have to make a
 792                         // copy of all variable arguments to not duplicate any side effect.
 793                         //
 794                         // ++d[++arg, Foo ()]
 795                         //
 796
 797                         if (!can_be_mutator)
 798                                 return base.CreateSetterArguments (rc, rhs);
 799
 800                         var setter_args = new Arguments (Arguments.Count + 1);
 801                         for (int i = 0; i < Arguments.Count; ++i) {
 802                                 var expr = Arguments[i].Expr;
 803
 804                                 if (expr is Constant || expr is VariableReference || expr is This) {
 805                                         setter_args.Add (Arguments [i]);
 806                                         continue;
 807                                 }
 808
 809                                 LocalVariable temp = LocalVariable.CreateCompilerGenerated (expr.Type, rc.CurrentBlock, loc);
 810                                 expr = new SimpleAssign (temp.CreateReferenceExpression (rc, expr.Location), expr).Resolve (rc);
 811                                 Arguments[i].Expr = temp.CreateReferenceExpression (rc, expr.Location).Resolve (rc);
 812                                 setter_args.Add (Arguments [i].Clone (expr));
 813                         }
 814
 815                         setter_args.Add (new Argument (rhs));
 816                         return setter_args;
 817                 }
 818
 819                 protected override bool IsConditionalAccessReceiver {
 820                         get {
 821                                 return conditional_access_receiver;
 822                         }
 823                 }
 824
 825                 public override bool HasConditionalAccess ()
 826                 {
 827                         return conditional_access;
 828                 }
 829         }
 830
 831         class DynamicInvocation : DynamicExpressionStatement, IDynamicBinder
 832         {
 833                 readonly ATypeNameExpression member;
 834                 readonly bool conditional_access_receiver;
 835
 836                 public DynamicInvocation (ATypeNameExpression member, Arguments args, bool conditionalAccessReceiver, Location loc)
 837                         : base (null, args, loc)
 838                 {
 839                         base.binder = this;
 840                         this.member = member;
 841                         this.conditional_access_receiver = conditionalAccessReceiver;
 842                 }
 843
 844                 public static DynamicInvocation CreateSpecialNameInvoke (ATypeNameExpression member, Arguments args, Location loc)
 845                 {
 846                         return new DynamicInvocation (member, args, false, loc) {
 847                                 flags = CSharpBinderFlags.InvokeSpecialName
 848                         };
 849                 }
 850
 851                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 852                 {
 853                         Arguments binder_args = new Arguments (member != null ? 5 : 3);
 854                         bool is_member_access = member is MemberAccess;
 855
 856                         CSharpBinderFlags call_flags;
 857                         if (!is_member_access && member is SimpleName) {
 858                                 call_flags = CSharpBinderFlags.InvokeSimpleName;
 859                                 is_member_access = true;
 860                         } else {
 861                                 call_flags = 0;
 862                         }
 863
 864                         binder_args.Add (new Argument (new BinderFlags (call_flags, this)));
 865
 866                         if (is_member_access)
 867                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, member.Name, member.Location)));
 868
 869                         if (member != null && member.HasTypeArguments) {
 870                                 TypeArguments ta = member.TypeArguments;
 871                                 if (ta.Resolve (ec, false)) {
 872                                         var targs = new ArrayInitializer (ta.Count, loc);
 873                                         foreach (TypeSpec t in ta.Arguments)
 874                                                 targs.Add (new TypeOf (t, loc));
 875
 876                                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (targs, loc)));
 877                                 }
 878                         } else if (is_member_access) {
 879                                 binder_args.Add (new Argument (new NullLiteral (loc)));
 880                         }
 881
 882                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 883
 884                         Expression real_args;
 885                         if (args == null) {
 886                                 // Cannot be null because .NET trips over
 887                                 real_args = new ArrayCreation (
 888                                         new MemberAccess (GetBinderNamespace (loc), "CSharpArgumentInfo", loc),
 889                                         new ArrayInitializer (0, loc), loc);
 890                         } else {
 891                                 real_args = new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc);
 892                         }
 893
 894                         binder_args.Add (new Argument (real_args));
 895
 896                         return new Invocation (GetBinder (is_member_access ? "InvokeMember" : "Invoke", loc), binder_args);
 897                 }
 898
 899                 public override void EmitStatement (EmitContext ec)
 900                 {
 901                         flags |= CSharpBinderFlags.ResultDiscarded;
 902                         base.EmitStatement (ec);
 903                 }
 904
 905                 protected override bool IsConditionalAccessReceiver {
 906                         get {
 907                                 return conditional_access_receiver;
 908                         }
 909                 }
 910
 911                 public override bool HasConditionalAccess ()
 912                 {
 913                         return member is ConditionalMemberAccess;
 914                 }
 915         }
 916
 917         class DynamicConditionalMemberBinder : DynamicMemberBinder
 918         {
 919                 public DynamicConditionalMemberBinder (string name, Arguments args, Location loc)
 920                         : base (name, args, loc)
 921                 {
 922                 }
 923
 924                 public override bool HasConditionalAccess ()
 925                 {
 926                         return true;
 927                 }
 928         }
 929
 930         class DynamicMemberBinder : DynamicMemberAssignable
 931         {
 932                 readonly string name;
 933                 bool conditionalAccessReceiver;
 934
 935                 public DynamicMemberBinder (string name, Arguments args, Location loc)
 936                         : base (args, loc)
 937                 {
 938                         this.name = name;
 939                 }
 940
 941                 public DynamicMemberBinder (string name, CSharpBinderFlags flags, Arguments args, Location loc)
 942                         : this (name, args, loc)
 943                 {
 944                         base.flags = flags;
 945                 }
 946
 947                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 948                 {
 949                         Arguments binder_args = new Arguments (4);
 950
 951                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 952                         binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
 953                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 954                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 955
 956                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
 957                         return new Invocation (GetBinder (isSet ? "SetMember" : "GetMember", loc), binder_args);
 958                 }
 959
 960                 protected override Expression DoResolve (ResolveContext rc)
 961                 {
 962                         if (!rc.HasSet (ResolveContext.Options.DontSetConditionalAccessReceiver))
 963                                 conditionalAccessReceiver = HasConditionalAccess () || Arguments [0].Expr.HasConditionalAccess ();
 964
 965                         return base.DoResolve (rc);
 966                 }
 967
 968                 protected override bool IsConditionalAccessReceiver {
 969                         get {
 970                                 return conditionalAccessReceiver;
 971                         }
 972                 }
 973         }
 974
 975         //
 976         // Any member binder which can be source and target of assignment
 977         //
 978         abstract class DynamicMemberAssignable : DynamicExpressionStatement, IDynamicBinder, IAssignMethod
 979         {
 980                 Expression setter;
 981                 Arguments setter_args;
 982
 983                 protected DynamicMemberAssignable (Arguments args, Location loc)
 984                         : base (null, args, loc)
 985                 {
 986                         base.binder = this;
 987                 }
 988
 989                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 990                 {
 991                         //
 992                         // DoResolve always uses getter
 993                         //
 994                         return CreateCallSiteBinder (ec, args, false);
 995                 }
 996
 997                 protected abstract Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet);
 998
 999                 protected virtual Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
1000                 {
1001                         var setter_args = new Arguments (Arguments.Count + 1);
1002                         setter_args.AddRange (Arguments);
1003                         setter_args.Add (new Argument (rhs));
1004                         return setter_args;
1005                 }
1006
1007                 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
1008                 {
1009                         if (right_side == EmptyExpression.OutAccess) {
1010                                 right_side.DoResolveLValue (rc, this);
1011                                 return null;
1012                         }
1013
1014                         if (DoResolveCore (rc)) {
1015                                 setter_args = CreateSetterArguments (rc, right_side);
1016                                 setter = CreateCallSiteBinder (rc, setter_args, true);
1017                         }
1018
1019                         eclass = ExprClass.Variable;
1020                         return this;
1021                 }
1022
1023                 public override void Emit (EmitContext ec)
1024                 {
1025                         // It's null for ResolveLValue used without assignment
1026                         if (binder_expr == null)
1027                                 EmitCall (ec, setter, Arguments, false);
1028                         else
1029                                 base.Emit (ec);
1030                 }
1031
1032                 public override void EmitStatement (EmitContext ec)
1033                 {
1034                         // It's null for ResolveLValue used without assignment
1035                         if (binder_expr == null)
1036                                 EmitCall (ec, setter, Arguments, true);
1037                         else
1038                                 base.EmitStatement (ec);
1039                 }
1040
1041                 #region IAssignMethod Members
1042
1043                 public void Emit (EmitContext ec, bool leave_copy)
1044                 {
1045                         throw new NotImplementedException ();
1046                 }
1047
1048                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
1049                 {
1050                         EmitCall (ec, setter, setter_args, !leave_copy);
1051                 }
1052
1053                 #endregion
1054         }
1055
1056         class DynamicUnaryConversion : DynamicExpressionStatement, IDynamicBinder
1057         {
1058                 readonly string name;
1059
1060                 public DynamicUnaryConversion (string name, Arguments args, Location loc)
1061                         : base (null, args, loc)
1062                 {
1063                         this.name = name;
1064                         base.binder = this;
1065                 }
1066
1067                 public static DynamicUnaryConversion CreateIsTrue (ResolveContext rc, Arguments args, Location loc)
1068                 {
1069                         return new DynamicUnaryConversion ("IsTrue", args, loc) { type = rc.BuiltinTypes.Bool };
1070                 }
1071
1072                 public static DynamicUnaryConversion CreateIsFalse (ResolveContext rc, Arguments args, Location loc)
1073                 {
1074                         return new DynamicUnaryConversion ("IsFalse", args, loc) { type = rc.BuiltinTypes.Bool };
1075                 }
1076
1077                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
1078                 {
1079                         Arguments binder_args = new Arguments (4);
1080
1081                         MemberAccess sle = new MemberAccess (new MemberAccess (
1082                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Linq", loc), "Expressions", loc);
1083
1084                         var flags = ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
1085
1086                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
1087                         binder_args.Add (new Argument (new MemberAccess (new MemberAccess (sle, "ExpressionType", loc), name, loc)));
1088                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
1089                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
1090
1091                         return new Invocation (GetBinder ("UnaryOperation", loc), binder_args);
1092                 }
1093         }
1094
1095         sealed class DynamicSiteClass : HoistedStoreyClass
1096         {
1097                 public DynamicSiteClass (TypeDefinition parent, MemberBase host, TypeParameters tparams)
1098                         : base (parent, MakeMemberName (host, "DynamicSite", parent.DynamicSitesCounter, tparams, Location.Null), tparams, Modifiers.STATIC, MemberKind.Class)
1099                 {
1100                         parent.DynamicSitesCounter++;
1101                 }
1102
1103                 public FieldSpec CreateCallSiteField (FullNamedExpression type, Location loc)
1104                 {
1105                         int index = AnonymousMethodsCounter++;
1106                         Field f = new HoistedField (this, type, Modifiers.PUBLIC | Modifiers.STATIC, "Site" + index.ToString ("X"), null, loc);
1107                         f.Define ();
1108
1109                         AddField (f);
1110                         return f.Spec;
1111                 }
1112         }
1113 }