Merge pull request #901 from Blewzman/FixAggregateExceptionGetBaseException
[mono.git] / 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
16 #if NET_4_0 || MOBILE_DYNAMIC
17 using System.Dynamic;
18 #endif
19
20 namespace Mono.CSharp
21 {
22         //
23         // A copy of Microsoft.CSharp/Microsoft.CSharp.RuntimeBinder/CSharpBinderFlags.cs
24         // has to be kept in sync
25         //
26         [Flags]
27         public enum CSharpBinderFlags
28         {
29                 None = 0,
30                 CheckedContext = 1,
31                 InvokeSimpleName = 1 << 1,
32                 InvokeSpecialName = 1 << 2,
33                 BinaryOperationLogical = 1 << 3,
34                 ConvertExplicit = 1 << 4,
35                 ConvertArrayIndex = 1 << 5,
36                 ResultIndexed = 1 << 6,
37                 ValueFromCompoundAssignment = 1 << 7,
38                 ResultDiscarded = 1 << 8
39         }
40
41         //
42         // Type expression with internal dynamic type symbol
43         //
44         class DynamicTypeExpr : TypeExpr
45         {
46                 public DynamicTypeExpr (Location loc)
47                 {
48                         this.loc = loc;
49                 }
50
51                 public override TypeSpec ResolveAsType (IMemberContext ec)
52                 {
53                         eclass = ExprClass.Type;
54                         type = ec.Module.Compiler.BuiltinTypes.Dynamic;
55                         return type;
56                 }
57         }
58
59         #region Dynamic runtime binder expressions
60
61         //
62         // Expression created from runtime dynamic object value by dynamic binder
63         //
64         public class RuntimeValueExpression : Expression, IDynamicAssign, IMemoryLocation
65         {
66 #if !NET_4_0 && !MOBILE_DYNAMIC
67                 public class DynamicMetaObject
68                 {
69                         public TypeSpec RuntimeType;
70                         public TypeSpec LimitType;
71                         public SLE.Expression Expression;
72                 }
73 #endif
74
75                 readonly DynamicMetaObject obj;
76
77                 public RuntimeValueExpression (DynamicMetaObject obj, TypeSpec type)
78                 {
79                         this.obj = obj;
80                         this.type = type;
81                         this.eclass = ExprClass.Variable;
82                 }
83
84                 #region Properties
85
86                 public bool IsSuggestionOnly { get; set; }
87
88                 public DynamicMetaObject MetaObject {
89                         get { return obj; }
90                 }
91
92                 #endregion
93
94                 public void AddressOf (EmitContext ec, AddressOp mode)
95                 {
96                         throw new NotImplementedException ();
97                 }
98
99                 public override bool ContainsEmitWithAwait ()
100                 {
101                         throw new NotSupportedException ();
102                 }
103
104                 public override Expression CreateExpressionTree (ResolveContext ec)
105                 {
106                         throw new NotSupportedException ();
107                 }
108
109                 protected override Expression DoResolve (ResolveContext ec)
110                 {
111                         return this;
112                 }
113
114                 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
115                 {
116                         return this;
117                 }
118
119                 public override void Emit (EmitContext ec)
120                 {
121                         throw new NotImplementedException ();
122                 }
123
124                 #region IAssignMethod Members
125
126                 public void Emit (EmitContext ec, bool leave_copy)
127                 {
128                         throw new NotImplementedException ();
129                 }
130
131                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
132                 {
133                         throw new NotImplementedException ();
134                 }
135
136                 #endregion
137
138                 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
139                 {
140                         return obj.Expression;
141                 }
142
143                 public override SLE.Expression MakeExpression (BuilderContext ctx)
144                 {
145 #if STATIC
146                         return base.MakeExpression (ctx);
147 #else
148
149 #if NET_4_0 || MOBILE_DYNAMIC
150                                 if (type.IsStruct && !obj.Expression.Type.IsValueType)
151                                         return SLE.Expression.Unbox (obj.Expression, type.GetMetaInfo ());
152
153                                 if (obj.Expression.NodeType == SLE.ExpressionType.Parameter) {
154                                         if (((SLE.ParameterExpression) obj.Expression).IsByRef)
155                                                 return obj.Expression;
156                                 }
157         #endif
158
159                                 return SLE.Expression.Convert (obj.Expression, type.GetMetaInfo ());
160 #endif
161                 }
162         }
163
164         //
165         // Wraps runtime dynamic expression into expected type. Needed
166         // to satify expected type check by dynamic binder and no conversion
167         // is required (ResultDiscarded).
168         //
169         public class DynamicResultCast : ShimExpression
170         {
171                 public DynamicResultCast (TypeSpec type, Expression expr)
172                         : base (expr)
173                 {
174                         this.type = type;
175                 }
176
177                 protected override Expression DoResolve (ResolveContext ec)
178                 {
179                         expr = expr.Resolve (ec);
180                         eclass = ExprClass.Value;
181                         return this;
182                 }
183
184 #if NET_4_0 || MOBILE_DYNAMIC
185                 public override SLE.Expression MakeExpression (BuilderContext ctx)
186                 {
187 #if STATIC
188                         return base.MakeExpression (ctx);
189 #else
190                         return SLE.Expression.Block (expr.MakeExpression (ctx), SLE.Expression.Default (type.GetMetaInfo ()));
191 #endif
192                 }
193 #endif
194         }
195
196         #endregion
197
198         //
199         // Creates dynamic binder expression
200         //
201         interface IDynamicBinder
202         {
203                 Expression CreateCallSiteBinder (ResolveContext ec, Arguments args);
204         }
205
206         //
207         // Extends standard assignment interface for expressions
208         // supported by dynamic resolver
209         //
210         interface IDynamicAssign : IAssignMethod
211         {
212                 SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
213         }
214
215         //
216         // Base dynamic expression statement creator
217         //
218         class DynamicExpressionStatement : ExpressionStatement
219         {
220                 //
221                 // Binder flag dynamic constant, the value is combination of
222                 // flags known at resolve stage and flags known only at emit
223                 // stage
224                 //
225                 protected class BinderFlags : EnumConstant
226                 {
227                         readonly DynamicExpressionStatement statement;
228                         readonly CSharpBinderFlags flags;
229
230                         public BinderFlags (CSharpBinderFlags flags, DynamicExpressionStatement statement)
231                                 : base (statement.loc)
232                         {
233                                 this.flags = flags;
234                                 this.statement = statement;
235                                 eclass = 0;
236                         }
237
238                         protected override Expression DoResolve (ResolveContext ec)
239                         {
240                                 Child = new IntConstant (ec.BuiltinTypes, (int) (flags | statement.flags), statement.loc);
241
242                                 type = ec.Module.PredefinedTypes.BinderFlags.Resolve ();
243                                 eclass = Child.eclass;
244                                 return this;
245                         }
246                 }
247
248                 readonly Arguments arguments;
249                 protected IDynamicBinder binder;
250                 protected Expression binder_expr;
251
252                 // Used by BinderFlags
253                 protected CSharpBinderFlags flags;
254
255                 TypeSpec binder_type;
256                 TypeParameters context_mvars;
257
258                 public DynamicExpressionStatement (IDynamicBinder binder, Arguments args, Location loc)
259                 {
260                         this.binder = binder;
261                         this.arguments = args;
262                         this.loc = loc;
263                 }
264
265                 public Arguments Arguments {
266                         get {
267                                 return arguments;
268                         }
269                 }
270
271                 public override bool ContainsEmitWithAwait ()
272                 {
273                         return arguments.ContainsEmitWithAwait ();
274                 }
275
276                 public override Expression CreateExpressionTree (ResolveContext ec)
277                 {
278                         ec.Report.Error (1963, loc, "An expression tree cannot contain a dynamic operation");
279                         return null;
280                 }
281
282                 protected override Expression DoResolve (ResolveContext rc)
283                 {
284                         if (DoResolveCore (rc))
285                                 binder_expr = binder.CreateCallSiteBinder (rc, arguments);
286
287                         return this;
288                 }
289
290                 protected bool DoResolveCore (ResolveContext rc)
291                 {
292                         if (rc.CurrentTypeParameters != null && rc.CurrentTypeParameters[0].IsMethodTypeParameter)
293                                 context_mvars = rc.CurrentTypeParameters;
294
295                         int errors = rc.Report.Errors;
296                         var pt = rc.Module.PredefinedTypes;
297
298                         binder_type = pt.Binder.Resolve ();
299                         pt.CallSite.Resolve ();
300                         pt.CallSiteGeneric.Resolve ();
301
302                         eclass = ExprClass.Value;
303
304                         if (type == null)
305                                 type = rc.BuiltinTypes.Dynamic;
306
307                         if (rc.Report.Errors == errors)
308                                 return true;
309
310                         rc.Report.Error (1969, loc,
311                                 "Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference");
312                         return false;
313                 }
314
315                 public override void Emit (EmitContext ec)
316                 {
317                         EmitCall (ec, binder_expr, arguments,  false);
318                 }
319
320                 public override void EmitStatement (EmitContext ec)
321                 {
322                         EmitCall (ec, binder_expr, arguments, true);
323                 }
324
325                 protected void EmitCall (EmitContext ec, Expression binder, Arguments arguments, bool isStatement)
326                 {
327                         //
328                         // This method generates all internal infrastructure for a dynamic call. The
329                         // reason why it's quite complicated is the mixture of dynamic and anonymous
330                         // methods. Dynamic itself requires a temporary class (ContainerX) and anonymous
331                         // methods can generate temporary storey as well (AnonStorey). Handling MVAR
332                         // type parameters rewrite is non-trivial in such case as there are various
333                         // combinations possible therefore the mutator is not straightforward. Secondly
334                         // we need to keep both MVAR(possibly VAR for anon storey) and type VAR to emit
335                         // correct Site field type and its access from EmitContext.
336                         //
337
338                         int dyn_args_count = arguments == null ? 0 : arguments.Count;
339                         int default_args = isStatement ? 1 : 2;
340                         var module = ec.Module;
341
342                         bool has_ref_out_argument = false;
343                         var targs = new TypeExpression[dyn_args_count + default_args];
344                         targs[0] = new TypeExpression (module.PredefinedTypes.CallSite.TypeSpec, loc);
345
346                         TypeExpression[] targs_for_instance = null;
347                         TypeParameterMutator mutator;
348
349                         var site_container = ec.CreateDynamicSite ();
350
351                         if (context_mvars != null) {
352                                 TypeParameters tparam;
353                                 TypeContainer sc = site_container;
354                                 do {
355                                         tparam = sc.CurrentTypeParameters;
356                                         sc = sc.Parent;
357                                 } while (tparam == null);
358
359                                 mutator = new TypeParameterMutator (context_mvars, tparam);
360
361                                 if (!ec.IsAnonymousStoreyMutateRequired) {
362                                         targs_for_instance = new TypeExpression[targs.Length];
363                                         targs_for_instance[0] = targs[0];
364                                 }
365                         } else {
366                                 mutator = null;
367                         }
368
369                         for (int i = 0; i < dyn_args_count; ++i) {
370                                 Argument a = arguments[i];
371                                 if (a.ArgType == Argument.AType.Out || a.ArgType == Argument.AType.Ref)
372                                         has_ref_out_argument = true;
373
374                                 var t = a.Type;
375
376                                 // Convert any internal type like dynamic or null to object
377                                 if (t.Kind == MemberKind.InternalCompilerType)
378                                         t = ec.BuiltinTypes.Object;
379
380                                 if (targs_for_instance != null)
381                                         targs_for_instance[i + 1] = new TypeExpression (t, loc);
382
383                                 if (mutator != null)
384                                         t = t.Mutate (mutator);
385
386                                 targs[i + 1] = new TypeExpression (t, loc);
387                         }
388
389                         TypeExpr del_type = null;
390                         TypeExpr del_type_instance_access = null;
391                         if (!has_ref_out_argument) {
392                                 string d_name = isStatement ? "Action" : "Func";
393
394                                 TypeSpec te = null;
395                                 Namespace type_ns = module.GlobalRootNamespace.GetNamespace ("System", true);
396                                 if (type_ns != null) {
397                                         te = type_ns.LookupType (module, d_name, dyn_args_count + default_args, LookupMode.Normal, loc);
398                                 }
399
400                                 if (te != null) {
401                                         if (!isStatement) {
402                                                 var t = type;
403                                                 if (t.Kind == MemberKind.InternalCompilerType)
404                                                         t = ec.BuiltinTypes.Object;
405
406                                                 if (targs_for_instance != null)
407                                                         targs_for_instance[targs_for_instance.Length - 1] = new TypeExpression (t, loc);
408
409                                                 if (mutator != null)
410                                                         t = t.Mutate (mutator);
411
412                                                 targs[targs.Length - 1] = new TypeExpression (t, loc);
413                                         }
414
415                                         del_type = new GenericTypeExpr (te, new TypeArguments (targs), loc);
416                                         if (targs_for_instance != null)
417                                                 del_type_instance_access = new GenericTypeExpr (te, new TypeArguments (targs_for_instance), loc);
418                                         else
419                                                 del_type_instance_access = del_type;
420                                 }
421                         }
422
423                         //
424                         // Create custom delegate when no appropriate predefined delegate has been found
425                         //
426                         Delegate d;
427                         if (del_type == null) {
428                                 TypeSpec rt = isStatement ? ec.BuiltinTypes.Void : type;
429                                 Parameter[] p = new Parameter[dyn_args_count + 1];
430                                 p[0] = new Parameter (targs[0], "p0", Parameter.Modifier.NONE, null, loc);
431
432                                 var site = ec.CreateDynamicSite ();
433                                 int index = site.Containers == null ? 0 : site.Containers.Count;
434
435                                 if (mutator != null)
436                                         rt = mutator.Mutate (rt);
437
438                                 for (int i = 1; i < dyn_args_count + 1; ++i) {
439                                         p[i] = new Parameter (targs[i], "p" + i.ToString ("X"), arguments[i - 1].Modifier, null, loc);
440                                 }
441
442                                 d = new Delegate (site, new TypeExpression (rt, loc),
443                                         Modifiers.INTERNAL | Modifiers.COMPILER_GENERATED,
444                                         new MemberName ("Container" + index.ToString ("X")),
445                                         new ParametersCompiled (p), null);
446
447                                 d.CreateContainer ();
448                                 d.DefineContainer ();
449                                 d.Define ();
450                                 d.PrepareEmit ();
451
452                                 site.AddTypeContainer (d);
453
454                                 //
455                                 // Add new container to inflated site container when the
456                                 // member cache already exists
457                                 //
458                                 if (site.CurrentType is InflatedTypeSpec && index > 0)
459                                         site.CurrentType.MemberCache.AddMember (d.CurrentType);
460
461                                 del_type = new TypeExpression (d.CurrentType, loc);
462                                 if (targs_for_instance != null) {
463                                         del_type_instance_access = null;
464                                 } else {
465                                         del_type_instance_access = del_type;
466                                 }
467                         } else {
468                                 d = null;
469                         }
470
471                         var site_type_decl = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec, new TypeArguments (del_type), loc);
472                         var field = site_container.CreateCallSiteField (site_type_decl, loc);
473                         if (field == null)
474                                 return;
475
476                         if (del_type_instance_access == null) {
477                                 var dt = d.CurrentType.DeclaringType.MakeGenericType (module, context_mvars.Types);
478                                 del_type_instance_access = new TypeExpression (MemberCache.GetMember (dt, d.CurrentType), loc);
479                         }
480
481                         var instanceAccessExprType = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec,
482                                 new TypeArguments (del_type_instance_access), loc);
483
484                         if (instanceAccessExprType.ResolveAsType (ec.MemberContext) == null)
485                                 return;
486
487                         bool inflate_using_mvar = context_mvars != null && ec.IsAnonymousStoreyMutateRequired;
488
489                         TypeSpec gt;
490                         if (inflate_using_mvar || context_mvars == null) {
491                                 gt = site_container.CurrentType;
492                         } else {
493                                 gt = site_container.CurrentType.MakeGenericType (module, context_mvars.Types);
494                         }
495
496                         // When site container already exists the inflated version has to be
497                         // updated manually to contain newly created field
498                         if (gt is InflatedTypeSpec && site_container.AnonymousMethodsCounter > 1) {
499                                 var tparams = gt.MemberDefinition.TypeParametersCount > 0 ? gt.MemberDefinition.TypeParameters : TypeParameterSpec.EmptyTypes;
500                                 var inflator = new TypeParameterInflator (module, gt, tparams, gt.TypeArguments);
501                                 gt.MemberCache.AddMember (field.InflateMember (inflator));
502                         }
503
504                         FieldExpr site_field_expr = new FieldExpr (MemberCache.GetMember (gt, field), loc);
505
506                         BlockContext bc = new BlockContext (ec.MemberContext, null, ec.BuiltinTypes.Void);
507
508                         Arguments args = new Arguments (1);
509                         args.Add (new Argument (binder));
510                         StatementExpression s = new StatementExpression (new SimpleAssign (site_field_expr, new Invocation (new MemberAccess (instanceAccessExprType, "Create"), args)));
511
512                         using (ec.With (BuilderContext.Options.OmitDebugInfo, true)) {
513                                 if (s.Resolve (bc)) {
514                                         Statement init = new If (new Binary (Binary.Operator.Equality, site_field_expr, new NullLiteral (loc)), s, loc);
515                                         init.Emit (ec);
516                                 }
517
518                                 args = new Arguments (1 + dyn_args_count);
519                                 args.Add (new Argument (site_field_expr));
520                                 if (arguments != null) {
521                                         int arg_pos = 1;
522                                         foreach (Argument a in arguments) {
523                                                 if (a is NamedArgument) {
524                                                         // Name is not valid in this context
525                                                         args.Add (new Argument (a.Expr, a.ArgType));
526                                                 } else {
527                                                         args.Add (a);
528                                                 }
529
530                                                 if (inflate_using_mvar && a.Type != targs[arg_pos].Type)
531                                                         a.Expr.Type = targs[arg_pos].Type;
532
533                                                 ++arg_pos;
534                                         }
535                                 }
536
537                                 Expression target = new DelegateInvocation (new MemberAccess (site_field_expr, "Target", loc).Resolve (bc), args, loc).Resolve (bc);
538                                 if (target != null)
539                                         target.Emit (ec);
540                         }
541                 }
542
543                 public override void FlowAnalysis (FlowAnalysisContext fc)
544                 {
545                         arguments.FlowAnalysis (fc);
546                 }
547
548                 public static MemberAccess GetBinderNamespace (Location loc)
549                 {
550                         return new MemberAccess (new MemberAccess (
551                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "Microsoft", loc), "CSharp", loc), "RuntimeBinder", loc);
552                 }
553
554                 protected MemberAccess GetBinder (string name, Location loc)
555                 {
556                         return new MemberAccess (new TypeExpression (binder_type, loc), name, loc);
557                 }
558         }
559
560         //
561         // Dynamic member access compound assignment for events
562         //
563         class DynamicEventCompoundAssign : ExpressionStatement
564         {
565                 class IsEvent : DynamicExpressionStatement, IDynamicBinder
566                 {
567                         string name;
568
569                         public IsEvent (string name, Arguments args, Location loc)
570                                 : base (null, args, loc)
571                         {
572                                 this.name = name;
573                                 binder = this;
574                         }
575
576                         public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
577                         {
578                                 type = ec.BuiltinTypes.Bool;
579
580                                 Arguments binder_args = new Arguments (3);
581
582                                 binder_args.Add (new Argument (new BinderFlags (0, this)));
583                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
584                                 binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
585
586                                 return new Invocation (GetBinder ("IsEvent", loc), binder_args);
587                         }
588                 }
589
590                 Expression condition;
591                 ExpressionStatement invoke, assign;
592
593                 public DynamicEventCompoundAssign (string name, Arguments args, ExpressionStatement assignment, ExpressionStatement invoke, Location loc)
594                 {
595                         condition = new IsEvent (name, args, loc);
596                         this.invoke = invoke;
597                         this.assign = assignment;
598                         this.loc = loc;
599                 }
600
601                 public override Expression CreateExpressionTree (ResolveContext ec)
602                 {
603                         return condition.CreateExpressionTree (ec);
604                 }
605
606                 protected override Expression DoResolve (ResolveContext rc)
607                 {
608                         type = rc.BuiltinTypes.Dynamic;
609                         eclass = ExprClass.Value;
610                         condition = condition.Resolve (rc);
611                         return this;
612                 }
613
614                 public override void Emit (EmitContext ec)
615                 {
616                         var rc = new ResolveContext (ec.MemberContext);
617                         var expr = new Conditional (new BooleanExpression (condition), invoke, assign, loc).Resolve (rc);
618                         expr.Emit (ec);
619                 }
620
621                 public override void EmitStatement (EmitContext ec)
622                 {
623                         var stmt = new If (condition, new StatementExpression (invoke), new StatementExpression (assign), loc);
624                         using (ec.With (BuilderContext.Options.OmitDebugInfo, true)) {
625                                 stmt.Emit (ec);
626                         }
627                 }
628
629                 public override void FlowAnalysis (FlowAnalysisContext fc)
630                 {
631                         invoke.FlowAnalysis (fc);
632                 }
633         }
634
635         class DynamicConversion : DynamicExpressionStatement, IDynamicBinder
636         {
637                 public DynamicConversion (TypeSpec targetType, CSharpBinderFlags flags, Arguments args, Location loc)
638                         : base (null, args, loc)
639                 {
640                         type = targetType;
641                         base.flags = flags;
642                         base.binder = this;
643                 }
644
645                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
646                 {
647                         Arguments binder_args = new Arguments (3);
648
649                         flags |= ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
650
651                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
652                         binder_args.Add (new Argument (new TypeOf (type, loc)));
653                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
654                         return new Invocation (GetBinder ("Convert", loc), binder_args);
655                 }
656         }
657
658         class DynamicConstructorBinder : DynamicExpressionStatement, IDynamicBinder
659         {
660                 public DynamicConstructorBinder (TypeSpec type, Arguments args, Location loc)
661                         : base (null, args, loc)
662                 {
663                         this.type = type;
664                         base.binder = this;
665                 }
666
667                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
668                 {
669                         Arguments binder_args = new Arguments (3);
670
671                         binder_args.Add (new Argument (new BinderFlags (0, this)));
672                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
673                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
674
675                         return new Invocation (GetBinder ("InvokeConstructor", loc), binder_args);
676                 }
677         }
678
679         class DynamicIndexBinder : DynamicMemberAssignable
680         {
681                 bool can_be_mutator;
682
683                 public DynamicIndexBinder (Arguments args, Location loc)
684                         : base (args, loc)
685                 {
686                 }
687
688                 public DynamicIndexBinder (CSharpBinderFlags flags, Arguments args, Location loc)
689                         : this (args, loc)
690                 {
691                         base.flags = flags;
692                 }
693
694                 protected override Expression DoResolve (ResolveContext ec)
695                 {
696                         can_be_mutator = true;
697                         return base.DoResolve (ec);
698                 }
699
700                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
701                 {
702                         Arguments binder_args = new Arguments (3);
703
704                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
705                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
706                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
707
708                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
709                         return new Invocation (GetBinder (isSet ? "SetIndex" : "GetIndex", loc), binder_args);
710                 }
711
712                 protected override Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
713                 {
714                         //
715                         // Indexer has arguments which complicates things as the setter and getter
716                         // are called in two steps when unary mutator is used. We have to make a
717                         // copy of all variable arguments to not duplicate any side effect.
718                         //
719                         // ++d[++arg, Foo ()]
720                         //
721
722                         if (!can_be_mutator)
723                                 return base.CreateSetterArguments (rc, rhs);
724
725                         var setter_args = new Arguments (Arguments.Count + 1);
726                         for (int i = 0; i < Arguments.Count; ++i) {
727                                 var expr = Arguments[i].Expr;
728
729                                 if (expr is Constant || expr is VariableReference || expr is This) {
730                                         setter_args.Add (Arguments [i]);
731                                         continue;
732                                 }
733
734                                 LocalVariable temp = LocalVariable.CreateCompilerGenerated (expr.Type, rc.CurrentBlock, loc);
735                                 expr = new SimpleAssign (temp.CreateReferenceExpression (rc, expr.Location), expr).Resolve (rc);
736                                 Arguments[i].Expr = temp.CreateReferenceExpression (rc, expr.Location).Resolve (rc);
737                                 setter_args.Add (Arguments [i].Clone (expr));
738                         }
739
740                         setter_args.Add (new Argument (rhs));
741                         return setter_args;
742                 }
743         }
744
745         class DynamicInvocation : DynamicExpressionStatement, IDynamicBinder
746         {
747                 readonly ATypeNameExpression member;
748
749                 public DynamicInvocation (ATypeNameExpression member, Arguments args, Location loc)
750                         : base (null, args, loc)
751                 {
752                         base.binder = this;
753                         this.member = member;
754                 }
755
756                 public static DynamicInvocation CreateSpecialNameInvoke (ATypeNameExpression member, Arguments args, Location loc)
757                 {
758                         return new DynamicInvocation (member, args, loc) {
759                                 flags = CSharpBinderFlags.InvokeSpecialName
760                         };
761                 }
762
763                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
764                 {
765                         Arguments binder_args = new Arguments (member != null ? 5 : 3);
766                         bool is_member_access = member is MemberAccess;
767
768                         CSharpBinderFlags call_flags;
769                         if (!is_member_access && member is SimpleName) {
770                                 call_flags = CSharpBinderFlags.InvokeSimpleName;
771                                 is_member_access = true;
772                         } else {
773                                 call_flags = 0;
774                         }
775
776                         binder_args.Add (new Argument (new BinderFlags (call_flags, this)));
777
778                         if (is_member_access)
779                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, member.Name, member.Location)));
780
781                         if (member != null && member.HasTypeArguments) {
782                                 TypeArguments ta = member.TypeArguments;
783                                 if (ta.Resolve (ec)) {
784                                         var targs = new ArrayInitializer (ta.Count, loc);
785                                         foreach (TypeSpec t in ta.Arguments)
786                                                 targs.Add (new TypeOf (t, loc));
787
788                                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (targs, loc)));
789                                 }
790                         } else if (is_member_access) {
791                                 binder_args.Add (new Argument (new NullLiteral (loc)));
792                         }
793
794                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
795
796                         Expression real_args;
797                         if (args == null) {
798                                 // Cannot be null because .NET trips over
799                                 real_args = new ArrayCreation (
800                                         new MemberAccess (GetBinderNamespace (loc), "CSharpArgumentInfo", loc),
801                                         new ArrayInitializer (0, loc), loc);
802                         } else {
803                                 real_args = new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc);
804                         }
805
806                         binder_args.Add (new Argument (real_args));
807
808                         return new Invocation (GetBinder (is_member_access ? "InvokeMember" : "Invoke", loc), binder_args);
809                 }
810
811                 public override void EmitStatement (EmitContext ec)
812                 {
813                         flags |= CSharpBinderFlags.ResultDiscarded;
814                         base.EmitStatement (ec);
815                 }
816         }
817
818         class DynamicMemberBinder : DynamicMemberAssignable
819         {
820                 readonly string name;
821
822                 public DynamicMemberBinder (string name, Arguments args, Location loc)
823                         : base (args, loc)
824                 {
825                         this.name = name;
826                 }
827
828                 public DynamicMemberBinder (string name, CSharpBinderFlags flags, Arguments args, Location loc)
829                         : this (name, args, loc)
830                 {
831                         base.flags = flags;
832                 }
833
834                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
835                 {
836                         Arguments binder_args = new Arguments (4);
837
838                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
839                         binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
840                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
841                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
842
843                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
844                         return new Invocation (GetBinder (isSet ? "SetMember" : "GetMember", loc), binder_args);
845                 }
846         }
847
848         //
849         // Any member binder which can be source and target of assignment
850         //
851         abstract class DynamicMemberAssignable : DynamicExpressionStatement, IDynamicBinder, IAssignMethod
852         {
853                 Expression setter;
854                 Arguments setter_args;
855
856                 protected DynamicMemberAssignable (Arguments args, Location loc)
857                         : base (null, args, loc)
858                 {
859                         base.binder = this;
860                 }
861
862                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
863                 {
864                         //
865                         // DoResolve always uses getter
866                         //
867                         return CreateCallSiteBinder (ec, args, false);
868                 }
869
870                 protected abstract Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet);
871
872                 protected virtual Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
873                 {
874                         var setter_args = new Arguments (Arguments.Count + 1);
875                         setter_args.AddRange (Arguments);
876                         setter_args.Add (new Argument (rhs));
877                         return setter_args;
878                 }
879
880                 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
881                 {
882                         if (right_side == EmptyExpression.OutAccess) {
883                                 right_side.DoResolveLValue (rc, this);
884                                 return null;
885                         }
886
887                         if (DoResolveCore (rc)) {
888                                 setter_args = CreateSetterArguments (rc, right_side);
889                                 setter = CreateCallSiteBinder (rc, setter_args, true);
890                         }
891
892                         eclass = ExprClass.Variable;
893                         return this;
894                 }
895
896                 public override void Emit (EmitContext ec)
897                 {
898                         // It's null for ResolveLValue used without assignment
899                         if (binder_expr == null)
900                                 EmitCall (ec, setter, Arguments, false);
901                         else
902                                 base.Emit (ec);
903                 }
904
905                 public override void EmitStatement (EmitContext ec)
906                 {
907                         // It's null for ResolveLValue used without assignment
908                         if (binder_expr == null)
909                                 EmitCall (ec, setter, Arguments, true);
910                         else
911                                 base.EmitStatement (ec);
912                 }
913
914                 #region IAssignMethod Members
915
916                 public void Emit (EmitContext ec, bool leave_copy)
917                 {
918                         throw new NotImplementedException ();
919                 }
920
921                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
922                 {
923                         EmitCall (ec, setter, setter_args, !leave_copy);
924                 }
925
926                 #endregion
927         }
928
929         class DynamicUnaryConversion : DynamicExpressionStatement, IDynamicBinder
930         {
931                 readonly string name;
932
933                 public DynamicUnaryConversion (string name, Arguments args, Location loc)
934                         : base (null, args, loc)
935                 {
936                         this.name = name;
937                         base.binder = this;
938                 }
939
940                 public static DynamicUnaryConversion CreateIsTrue (ResolveContext rc, Arguments args, Location loc)
941                 {
942                         return new DynamicUnaryConversion ("IsTrue", args, loc) { type = rc.BuiltinTypes.Bool };
943                 }
944
945                 public static DynamicUnaryConversion CreateIsFalse (ResolveContext rc, Arguments args, Location loc)
946                 {
947                         return new DynamicUnaryConversion ("IsFalse", args, loc) { type = rc.BuiltinTypes.Bool };
948                 }
949
950                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
951                 {
952                         Arguments binder_args = new Arguments (4);
953
954                         MemberAccess sle = new MemberAccess (new MemberAccess (
955                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Linq", loc), "Expressions", loc);
956
957                         var flags = ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
958
959                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
960                         binder_args.Add (new Argument (new MemberAccess (new MemberAccess (sle, "ExpressionType", loc), name, loc)));
961                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
962                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
963
964                         return new Invocation (GetBinder ("UnaryOperation", loc), binder_args);
965                 }
966         }
967
968         sealed class DynamicSiteClass : HoistedStoreyClass
969         {
970                 public DynamicSiteClass (TypeDefinition parent, MemberBase host, TypeParameters tparams)
971                         : base (parent, MakeMemberName (host, "DynamicSite", parent.DynamicSitesCounter, tparams, Location.Null), tparams, Modifiers.STATIC, MemberKind.Class)
972                 {
973                         parent.DynamicSitesCounter++;
974                 }
975
976                 public FieldSpec CreateCallSiteField (FullNamedExpression type, Location loc)
977                 {
978                         int index = AnonymousMethodsCounter++;
979                         Field f = new HoistedField (this, type, Modifiers.PUBLIC | Modifiers.STATIC, "Site" + index.ToString ("X"), null, loc);
980                         f.Define ();
981
982                         AddField (f);
983                         return f.Spec;
984                 }
985         }
986 }