X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=mcs%2Fmcs%2Fargument.cs;h=a5edeb53cf68b8e77b94dcf7a5363131038c423a;hb=e4559812129b62624444ab4ce96ddf2ca7de5e3d;hp=c516ffde5b0f080798142ce2e2d361745c4f6104;hpb=d12330eda7746321b4611865d11e932e53ac55b8;p=mono.git

diff --git a/mcs/mcs/argument.cs b/mcs/mcs/argument.cs
index c516ffde5b0..a5edeb53cf6 100644
--- a/mcs/mcs/argument.cs
+++ b/mcs/mcs/argument.cs
@@ -34,6 +34,11 @@ namespace Mono.CSharp
 			Default = 3,		// argument created from default parameter value
 			DynamicTypeName = 4,	// System.Type argument for dynamic binding
 			ExtensionType = 5,	// Instance expression inserted as the first argument
+
+			// Conditional instance expression inserted as the first argument
+			ExtensionTypeConditionalAccess = 5 | ConditionalAccessFlag,
+
+			ConditionalAccessFlag = 1 << 7
 		}
 
 		public readonly AType ArgType;
@@ -60,6 +65,12 @@ namespace Mono.CSharp
 			get { return ArgType == AType.Default; }
 		}
 
+		public bool IsExtensionType {
+			get {
+				return (ArgType & AType.ExtensionType) == AType.ExtensionType;
+			}
+		}
+
 		public Parameter.Modifier Modifier {
 			get {
 				switch (ArgType) {
@@ -105,7 +116,13 @@ namespace Mono.CSharp
 		public virtual void Emit (EmitContext ec)
 		{
 			if (!IsByRef) {
-				Expr.Emit (ec);
+				if (ArgType == AType.ExtensionTypeConditionalAccess) {
+					var ie = new InstanceEmitter (Expr, false);
+					ie.Emit (ec, true);
+				} else {
+					Expr.Emit (ec);
+				}
+
 				return;
 			}
 
@@ -276,6 +293,16 @@ namespace Mono.CSharp
 				ordered.Add (arg);
 			}
 
+			public override void FlowAnalysis (FlowAnalysisContext fc, List<MovableArgument> movable = null)
+			{
+				foreach (var arg in ordered) {
+					if (arg.ArgType != Argument.AType.Out)
+						arg.FlowAnalysis (fc);
+				}
+
+				base.FlowAnalysis (fc, ordered);
+			}
+
 			public override Arguments Emit (EmitContext ec, bool dup_args, bool prepareAwait)
 			{
 				foreach (var a in ordered) {
@@ -497,10 +524,34 @@ namespace Mono.CSharp
 			return null;
 		}
 
-		public void FlowAnalysis (FlowAnalysisContext fc)
+		public virtual void FlowAnalysis (FlowAnalysisContext fc, List<MovableArgument> movable = null)
 		{
-			foreach (var arg in args)
+			bool has_out = false;
+			foreach (var arg in args) {
+				if (arg.ArgType == Argument.AType.Out) {
+					has_out = true;
+					continue;
+				}
+
+				if (movable == null) {
+					arg.FlowAnalysis (fc);
+					continue;
+				}
+
+				var ma = arg as MovableArgument;
+				if (ma != null && !movable.Contains (ma))
+					arg.FlowAnalysis (fc);
+			}
+
+			if (!has_out)
+				return;
+
+			foreach (var arg in args) {
+				if (arg.ArgType != Argument.AType.Out)
+					continue;
+
 				arg.FlowAnalysis (fc);
+			}
 		}
 
 		public List<Argument>.Enumerator GetEnumerator ()