anonymous.cs

C#编译器源代码。Micorsoft开放源代码

			}
			
			public override void Emit (EmitContext ec)
			{
				am.aec.EmitMethodHostInstance (ec, am);
			}
		}
	}

	class CapturedParameter {
		public Type Type;
		public FieldBuilder FieldBuilder;
		public int Idx;

		public CapturedParameter (Type type, int idx)
		{
			Type = type;
			Idx = idx;
		}
	}

	//
	// Here we cluster all the variables captured on a given scope, we also
	// keep some extra information that might be required on each scope.
	//
	public class ScopeInfo {
		public CaptureContext CaptureContext;
		public ScopeInfo ParentScope;
		public Block ScopeBlock;
		public bool NeedThis = false;
		public bool HostsParameters = false;
		
		// For tracking the number of scopes created.
		public int id;
		static int count;
		bool inited = false;
		
		ArrayList locals = new ArrayList ();
		ArrayList children = new ArrayList ();

		//
		// The types and fields generated
		//
		public TypeBuilder ScopeTypeBuilder;
		public ConstructorBuilder ScopeConstructor;
		public FieldBuilder THIS;
		public FieldBuilder ParentLink;

		//
		// Points to the object of type `ScopeTypeBuilder' that
		// holds the data for the scope
		//
		LocalBuilder scope_instance;
		
		public ScopeInfo (CaptureContext cc, Block b)
		{
			CaptureContext = cc;
			ScopeBlock = b;
			id = count++;

			cc.AddScope (this);
		}

		public void AddLocal (LocalInfo li)
		{
			if (locals.Contains (li))
				return;

			locals.Add (li);
		}

		public bool IsCaptured (LocalInfo li)
		{
			return locals.Contains (li);
		}
		
		internal void AddChild (ScopeInfo si)
		{
			if (children.Contains (si))
				return;

			//
			// If any of the current children should be a children of `si', move them there
			//
			ArrayList move_queue = null;
			foreach (ScopeInfo child in children){
				if (child.ScopeBlock.IsChildOf (si.ScopeBlock)){
					if (move_queue == null)
						move_queue = new ArrayList ();
					move_queue.Add (child);
					child.ParentScope = si;
					si.AddChild (child);
				}
			}
			
			children.Add (si);

			if (move_queue != null){
				foreach (ScopeInfo child in move_queue){
					children.Remove (child);
				}
			}
		} 

		static int indent = 0;

		void Pad ()
		{
			for (int i = 0; i < indent; i++)
				Console.Write ("    ");
		}

		void EmitDebug ()
		{
			//Console.WriteLine (Environment.StackTrace);
			Pad ();
			Console.WriteLine ("START");
			indent++;
			Pad ();
			Console.WriteLine ("NeedThis=" + NeedThis);
			foreach (LocalInfo li in locals){
				Pad ();
				Console.WriteLine ("var {0}", MakeFieldName (li.Name));
			}
			
			foreach (ScopeInfo si in children)
				si.EmitDebug ();
			indent--;
			Pad ();
			Console.WriteLine ("END");
		}
		
		public string MakeHelperName ()
		{
			return String.Format ("<>AnonHelp<{0}>", id);
		}

		private string MakeFieldName (string local_name)
		{
			return "<" + id + ":" + local_name + ">";
		}

		public void EmitScopeType (EmitContext ec)
		{
			// EmitDebug ();

			if (ScopeTypeBuilder != null)
				return;
			
			TypeBuilder container = ec.TypeContainer.TypeBuilder;

			CaptureContext.Host.CreateScopeType (ec, this);
			
			if (NeedThis)
				THIS = ScopeTypeBuilder.DefineField ("<>THIS", container, FieldAttributes.Assembly);

			if (ParentScope != null){
				if (ParentScope.ScopeTypeBuilder == null){
					throw new Exception (String.Format ("My parent has not been initialized {0} and {1}", ParentScope, this));
				}

				if (ParentScope.ScopeTypeBuilder != ScopeTypeBuilder)
					ParentLink = ScopeTypeBuilder.DefineField ("<>parent", ParentScope.ScopeTypeBuilder,
										   FieldAttributes.Assembly);
			}
			
			if (NeedThis && ParentScope != null)
				throw new Exception ("I was not expecting THIS && having a parent");

			foreach (LocalInfo info in locals)
				info.FieldBuilder = ScopeTypeBuilder.DefineField (
					MakeFieldName (info.Name), info.VariableType, FieldAttributes.Assembly);

			if (HostsParameters){
				Hashtable captured_parameters = CaptureContext.captured_parameters;
				
				foreach (DictionaryEntry de in captured_parameters){
					string name = (string) de.Key;
					CapturedParameter cp = (CapturedParameter) de.Value;
					FieldBuilder fb;
					
					fb = ScopeTypeBuilder.DefineField ("<p:" + name + ">", cp.Type, FieldAttributes.Assembly);
					cp.FieldBuilder = fb;
				}
			}

			foreach (ScopeInfo si in children){
				si.EmitScopeType (ec);
			}
		}

		public void CloseTypes ()
		{
			RootContext.RegisterCompilerGeneratedType (ScopeTypeBuilder);
			foreach (ScopeInfo si in children)
				si.CloseTypes ();
		}

		//
		// Emits the initialization code for the scope
		//
		public void EmitInitScope (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			if (inited)
				return;

			if (ScopeConstructor == null)
				throw new Exception ("ScopeConstructor is null for" + this.ToString ());
			
			if (!CaptureContext.Host.IsIterator) {
				scope_instance = ig.DeclareLocal (ScopeTypeBuilder);
				ig.Emit (OpCodes.Newobj, (ConstructorInfo) ScopeConstructor);
				ig.Emit (OpCodes.Stloc, scope_instance);
			}

			if (THIS != null){
				if (CaptureContext.Host.IsIterator) {
					ig.Emit (OpCodes.Ldarg_0);
					ig.Emit (OpCodes.Ldarg_1);
				} else {
					ig.Emit (OpCodes.Ldloc, scope_instance);
					ig.Emit (OpCodes.Ldarg_0);
				}
				ig.Emit (OpCodes.Stfld, THIS);
			}

			//
			// Copy the parameter values, if any
			//
			int extra = ec.IsStatic ? 0 : 1;
			if (CaptureContext.Host.IsIterator)
				extra++;
			if (HostsParameters){
				Hashtable captured_parameters = CaptureContext.captured_parameters;
				
				foreach (DictionaryEntry de in captured_parameters){
					CapturedParameter cp = (CapturedParameter) de.Value;

					EmitScopeInstance (ig);
					ParameterReference.EmitLdArg (ig, cp.Idx + extra);
					ig.Emit (OpCodes.Stfld, cp.FieldBuilder);
				}
			}

			if (ParentScope != null){
				if (!ParentScope.inited)
					ParentScope.EmitInitScope (ec);

				if (ParentScope.ScopeTypeBuilder != ScopeTypeBuilder) {
					//
					// Only emit initialization in our capturecontext world
					//
					if (ParentScope.CaptureContext == CaptureContext){
						EmitScopeInstance (ig);
						ParentScope.EmitScopeInstance (ig);
						ig.Emit (OpCodes.Stfld, ParentLink);
					} else {
						EmitScopeInstance (ig);
						ig.Emit (OpCodes.Ldarg_0);
						ig.Emit (OpCodes.Stfld, ParentLink);
					}
				}
			}
			inited = true;
		}

		public void EmitScopeInstance (ILGenerator ig)
		{
			if (CaptureContext.Host.IsIterator)
				ig.Emit (OpCodes.Ldarg_0);
			else
				ig.Emit (OpCodes.Ldloc, scope_instance);
		}

		static void DoPath (StringBuilder sb, ScopeInfo start)
		{
			if (start.ParentScope != null){
				DoPath (sb, start.ParentScope);
				sb.Append (", ");
			}
			sb.Append ((start.id).ToString ());
		}
		
		public override string ToString ()
		{
			StringBuilder sb = new StringBuilder ();
			
			sb.Append ("{");
			if (CaptureContext != null){
				sb.Append (CaptureContext.ToString ());
				sb.Append (":");
			}

			DoPath (sb, this);
			sb.Append ("}");

			return sb.ToString ();
		}
	}

	//
	// CaptureContext objects are created on demand if a method has
	// anonymous methods and kept on the ToplevelBlock.
	//
	// If they exist, all ToplevelBlocks in the containing block are
	// linked together (children pointing to their parents).
	//
	public class CaptureContext {
		public static int count;
		public int cc_id;
		public Location loc;
		
		//
		// Points to the toplevel block that owns this CaptureContext
		//
		ToplevelBlock toplevel_owner;
		Hashtable scopes = new Hashtable ();
		bool have_captured_vars = false;
		bool referenced_this = false;
		ScopeInfo topmost = null;

		//
		// Captured fields
		//
		Hashtable captured_fields = new Hashtable ();
		Hashtable captured_variables = new Hashtable ();
		public Hashtable captured_parameters = new Hashtable ();
		public AnonymousContainer Host;
		
		public CaptureContext (ToplevelBlock toplevel_owner, Location loc,
				       AnonymousContainer host)
		{
			cc_id = count++;
			this.toplevel_owner = toplevel_owner;
			this.loc = loc;

			if (host != null)
				Host = host;
		}

		void DoPath (StringBuilder sb, CaptureContext cc)
		{
			if (cc.ParentCaptureContext != null){
				DoPath (sb, cc.ParentCaptureContext);
				sb.Append (".");
			}
			sb.Append (cc.cc_id.ToString ());
		}

		public void ReParent (ToplevelBlock new_toplevel, AnonymousContainer new_host)
		{
			toplevel_owner = new_toplevel;
			Host = new_host;

			for (CaptureContext cc = ParentCaptureContext; cc != null;
			     cc = cc.ParentCaptureContext) {
				cc.Host = new_host;
			}
		}
		
		public override string ToString ()
		{
			StringBuilder sb = new StringBuilder ();
			sb.Append ("[");
			DoPath (sb, this);
			sb.Append ("]");
			return sb.ToString ();
		}

		public ToplevelBlock ParentToplevel {
			get {
				return toplevel_owner.Container;
			}
		}

		public CaptureContext ParentCaptureContext {
			get {
				ToplevelBlock parent = ParentToplevel;
				
				return (parent == null) ? null : parent.CaptureContext;
			}
		}

		// Returns the deepest of two scopes
		public ScopeInfo Deepest (ScopeInfo a, ScopeInfo b)
		{
			ScopeInfo p;

			if (a == null)
				return b;
			if (b == null)
				return a;
			if (a == b)
				return a;

			//
			// If they Scopes are on the same CaptureContext, we do the double
			// checks just so if there is an invariant change in the future,
			// we get the exception at the end
			//
			for (p = a; p != null; p = p.ParentScope)
				if (p == b)
					return a;
			
			for (p = b; p != null; p = p.ParentScope)
				if (p == a)
					return b;

			CaptureContext ca = a.CaptureContext;
			CaptureContext cb = b.CaptureContext;

			for (CaptureContext c = ca; c != null; c = c.ParentCaptureContext)
				if (c == cb)
					return a;

			for (CaptureContext c = cb; c != null; c = c.ParentCaptureContext)
				if (c == ca)
					return b;
			throw new Exception ("Should never be reached");
		}

		void AdjustMethodScope (AnonymousContainer am, ScopeInfo scope)
		{
			am.Scope = Deepest (am.Scope, scope);
		}

		void LinkScope (ScopeInfo scope, int id)
		{
			ScopeInfo parent = (ScopeInfo) scopes [id];
			scope.ParentScope = parent;
			parent.AddChild (scope);

			if (scope == topmost)