[Decompiler] gpt-slop copy

ICSharpCode.Decompiler/CSharp/ExpressionBuilder.cs

@@ -558,6 +558,11 @@ namespace ICSharpCode.Decompiler.CSharp
 			return new CallBuilder(this, typeSystem, settings).Build(inst, context.TypeHint);
 		}
 
+		protected internal override TranslatedExpression VisitCachedDelegate(CachedDelegate inst, TranslationContext context)
+		{
+			return Translate(inst.Argument, context.TypeHint).WithILInstruction(inst);
+		}
+
 		protected internal override TranslatedExpression VisitLdVirtDelegate(LdVirtDelegate inst, TranslationContext context)
 		{
 			return new CallBuilder(this, typeSystem, settings).Build(inst);

ICSharpCode.Decompiler/CSharp/TranslatedExpression.cs

@@ -27,6 +27,7 @@ using ICSharpCode.Decompiler.CSharp.Transforms;
 using ICSharpCode.Decompiler.IL;
 using ICSharpCode.Decompiler.Semantics;
 using ICSharpCode.Decompiler.TypeSystem;
+using ICSharpCode.Decompiler.TypeSystem.Implementation;
 using ICSharpCode.Decompiler.Util;
 
 #nullable enable
@@ -270,6 +271,16 @@ namespace ICSharpCode.Decompiler.CSharp
 							else if (Expression is ObjectCreateExpression oce && conversion.Conversion.IsMethodGroupConversion
 								  && oce.Arguments.Count == 1 && expressionBuilder.settings.UseImplicitMethodGroupConversion)
 							{
+								// C# 11 caches static method groups. Keep explicit construction when the IL creates a fresh delegate.
+								if (conversion.Conversion.Method.IsStatic
+									&& conversion.Conversion.Method is not LocalFunctionMethod { IsStaticLocalFunction: false }
+									&& conversion.Conversion.Method.Parameters.Count == type.GetDelegateInvokeMethod()?.Parameters.Count
+									&& expressionBuilder.settings.GetMinimumRequiredVersion() >= LanguageVersion.CSharp11_0
+									&& expressionBuilder.currentFunction.Kind != ILFunctionKind.ExpressionTree
+									&& !ILInstructions.Any(i => i is CachedDelegate))
+								{
+									return this;
+								}
 								return this.UnwrapChild(oce.Arguments.Single());
 							}
 							break;

ICSharpCode.Decompiler/FlowAnalysis/DataFlowVisitor.cs

@@ -754,6 +754,15 @@ namespace ICSharpCode.Decompiler.FlowAnalysis
 			HandleBinaryWithOptionalEvaluation(inst, inst.ValueInst, inst.FallbackInst);
 		}
 
+		protected internal override void VisitCachedDelegate(CachedDelegate inst)
+		{
+			DebugStartPoint(inst);
+			State cachedState = state.Clone();
+			inst.Argument.AcceptVisitor(this);
+			state.JoinWith(cachedState);
+			DebugEndPoint(inst);
+		}
+
 		protected internal override void VisitDynamicLogicOperatorInstruction(DynamicLogicOperatorInstruction inst)
 		{
 			HandleBinaryWithOptionalEvaluation(inst, inst.Left, inst.Right);

ICSharpCode.Decompiler/IL/Instructions.cs

@@ -177,6 +177,8 @@ namespace ICSharpCode.Decompiler.IL
 		UnboxAny,
 		/// <summary>Creates an object instance and calls the constructor.</summary>
 		NewObj,
+		/// <summary>Reuses a cached delegate, evaluating the argument only when the cache is empty.</summary>
+		CachedDelegate,
 		/// <summary>Creates an array instance.</summary>
 		NewArr,
 		/// <summary>Returns the default value for a type.</summary>
@@ -4580,6 +4582,103 @@ namespace ICSharpCode.Decompiler.IL
 	}
 }
 namespace ICSharpCode.Decompiler.IL
+{
+	/// <summary>Reuses a cached delegate, evaluating the argument only when the cache is empty.</summary>
+	public sealed partial class CachedDelegate : ILInstruction
+	{
+		public CachedDelegate(ILInstruction argument) : base(OpCode.CachedDelegate)
+		{
+			this.Argument = argument;
+		}
+		public static readonly SlotInfo ArgumentSlot = new SlotInfo("Argument");
+		ILInstruction argument = null!;
+		public ILInstruction Argument {
+			get { return this.argument; }
+			set {
+				ValidateChild(value);
+				SetChildInstruction(ref this.argument, value, 0);
+			}
+		}
+		protected sealed override int GetChildCount()
+		{
+			return 1;
+		}
+		protected sealed override ILInstruction GetChild(int index)
+		{
+			switch (index)
+			{
+				case 0:
+					return this.argument;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		protected sealed override void SetChild(int index, ILInstruction value)
+		{
+			switch (index)
+			{
+				case 0:
+					this.Argument = value;
+					break;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		protected sealed override SlotInfo GetChildSlot(int index)
+		{
+			switch (index)
+			{
+				case 0:
+					return ArgumentSlot;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		public sealed override ILInstruction Clone()
+		{
+			var clone = (CachedDelegate)ShallowClone();
+			clone.Argument = this.argument.Clone();
+			return clone;
+		}
+		public override StackType ResultType => Argument.ResultType;
+		public override IType InferType(ICompilation compilation) => Argument.InferType(compilation);
+		protected override InstructionFlags ComputeFlags()
+		{
+			return argument.Flags | InstructionFlags.ControlFlow;
+		}
+		public override InstructionFlags DirectFlags {
+			get {
+				return InstructionFlags.ControlFlow;
+			}
+		}
+		protected override void WriteToCore(ITextOutput output, ILAstWritingOptions options)
+		{
+			WriteILRange(output, options);
+			output.Write(OpCode);
+			output.Write('(');
+			this.argument.WriteTo(output, options);
+			output.Write(')');
+		}
+		public override void AcceptVisitor(ILVisitor visitor)
+		{
+			visitor.VisitCachedDelegate(this);
+		}
+		public override T AcceptVisitor<T>(ILVisitor<T> visitor)
+		{
+			return visitor.VisitCachedDelegate(this);
+		}
+		public override T AcceptVisitor<C, T>(ILVisitor<C, T> visitor, C context)
+		{
+			return visitor.VisitCachedDelegate(this, context);
+		}
+		protected internal override bool PerformMatch(ILInstruction? other, ref Patterns.Match match)
+		{
+			var o = other as CachedDelegate;
+			return o != null && this.argument.PerformMatch(o.argument, ref match);
+		}
+	}
+}
+namespace ICSharpCode.Decompiler.IL
 {
 	/// <summary>Creates an array instance.</summary>
 	public sealed partial class NewArr : ILInstruction
@@ -7412,6 +7511,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			Default(inst);
 		}
+		protected internal virtual void VisitCachedDelegate(CachedDelegate inst)
+		{
+			Default(inst);
+		}
 		protected internal virtual void VisitNewArr(NewArr inst)
 		{
 			Default(inst);
@@ -7822,6 +7925,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			return Default(inst);
 		}
+		protected internal virtual T VisitCachedDelegate(CachedDelegate inst)
+		{
+			return Default(inst);
+		}
 		protected internal virtual T VisitNewArr(NewArr inst)
 		{
 			return Default(inst);
@@ -8232,6 +8339,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			return Default(inst, context);
 		}
+		protected internal virtual T VisitCachedDelegate(CachedDelegate inst, C context)
+		{
+			return Default(inst, context);
+		}
 		protected internal virtual T VisitNewArr(NewArr inst, C context)
 		{
 			return Default(inst, context);
@@ -8433,6 +8544,7 @@ namespace ICSharpCode.Decompiler.IL
 			"unbox",
 			"unbox.any",
 			"newobj",
+			"cached.delegate",
 			"newarr",
 			"default.value",
 			"throw",
@@ -9003,6 +9115,17 @@ namespace ICSharpCode.Decompiler.IL
 			type = default(IType);
 			return false;
 		}
+		public bool MatchCachedDelegate([NotNullWhen(true)] out ILInstruction? argument)
+		{
+			var inst = this as CachedDelegate;
+			if (inst != null)
+			{
+				argument = inst.Argument;
+				return true;
+			}
+			argument = default(ILInstruction);
+			return false;
+		}
 		public bool MatchNewArr([NotNullWhen(true)] out IType? type)
 		{
 			var inst = this as NewArr;

ICSharpCode.Decompiler/IL/Instructions.tt

@@ -287,6 +287,9 @@
 			Unary, HasTypeOperand, MemoryAccess, MayThrow, ResultType("this.type")),
 		new OpCode("newobj", "Creates an object instance and calls the constructor.",
 			CustomClassName("NewObj"), Call, ResultType("Method.DeclaringType")),
+		new OpCode("cached.delegate", "Reuses a cached delegate, evaluating the argument only when the cache is empty.",
+			CustomChildren(new [] { new ChildInfo("argument") }), ControlFlow,
+			ResultType("Argument.InferType(compilation)", "Argument.ResultType")),
 		new OpCode("newarr", "Creates an array instance.",
 			CustomClassName("NewArr"), HasTypeOperand,
 			CustomChildren(new [] { new ArgumentInfo("indices") { IsCollection = true } }, true),

ICSharpCode.Decompiler/IL/Transforms/CachedDelegateInitialization.cs

@@ -79,7 +79,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		/// }
 		/// ... one usage of CachedAnonMethodDelegate ...
 		/// =>
-		/// ... one usage of DelegateConstruction ...
+		/// ... one usage of cached.delegate(DelegateConstruction) ...
 		/// </summary>
 		bool CachedDelegateInitializationWithField(IfInstruction inst)
 		{
@@ -101,7 +101,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (usages.Length != 1)
 				return false;
 			context.Step("CachedDelegateInitializationWithField", inst);
-			usages[0].ReplaceWith(value);
+			usages[0].ReplaceWith(new CachedDelegate(value));
 			context.EndStep(value);
 			return true;
 		}
@@ -111,7 +111,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		///     stloc v(DelegateConstruction)
 		/// }
 		/// =>
-		/// stloc v(DelegateConstruction)
+		/// stloc v(cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationWithLocal(IfInstruction inst)
 		{
@@ -141,6 +141,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 				return false;
 			context.Step("CachedDelegateInitializationWithLocal", inst);
 			((Block)otherStore.Parent).Instructions.Remove(otherStore);
+			((StLoc)storeInst).Value = new CachedDelegate(value);
 			inst.ReplaceWith(storeInst);
 			context.EndStep(storeInst);
 			return true;
@@ -152,7 +153,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		///		stloc s(stobj(ldsflda(CachedAnonMethodDelegate), DelegateConstruction))
 		///	}
 		///	=>
-		///	stloc s(DelegateConstruction)
+		///	stloc s(cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationRoslynInStaticWithLocal(IfInstruction inst)
 		{
@@ -174,7 +175,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (!DelegateConstruction.MatchDelegateConstruction((NewObj)stobj.Value, out _, out _, out _, true))
 				return false;
 			context.Step("CachedDelegateInitializationRoslynInStaticWithLocal", inst);
-			storeBeforeIf.Value = stobj.Value;
+			storeBeforeIf.Value = new CachedDelegate(stobj.Value);
 			return true;
 		}
 
@@ -184,7 +185,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		///		stloc s(stobj(ldflda(CachedAnonMethodDelegate), DelegateConstruction))
 		///	}
 		///	=>
-		///	stloc s(DelegateConstruction)
+		///	stloc s(cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationRoslynWithLocal(IfInstruction inst)
 		{
@@ -206,7 +207,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (!DelegateConstruction.MatchDelegateConstruction((NewObj)stobj.Value, out _, out _, out _, true))
 				return false;
 			context.Step("CachedDelegateInitializationRoslynWithLocal", inst);
-			storeBeforeIf.Value = stobj.Value;
+			storeBeforeIf.Value = new CachedDelegate(stobj.Value);
 			return true;
 		}
 
@@ -217,7 +218,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		/// 	stloc s(ldobj System.Action(ldsflda $I4-1))
 		/// }
 		/// =>
-		///	stloc s(DelegateConstruction)
+		///	stloc s(cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationVB(IfInstruction inst)
 		{
@@ -249,7 +250,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (!DelegateConstruction.MatchDelegateConstruction(delegateConstruction, out _, out _, out _, true))
 				return false;
 			context.Step("CachedDelegateInitializationVB", inst);
-			var stloc = new StLoc(s, delegateConstruction);
+			var stloc = new StLoc(s, new CachedDelegate(delegateConstruction));
 			inst.ReplaceWith(stloc);
 			context.EndStep(stloc);
 			return true;
@@ -261,7 +262,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		/// }
 		///	leave IL_0005 (stsfld CachedAnonMethodDelegate(DelegateConstruction))
 		/// =>
-		/// leave IL_0005 (DelegateConstruction)
+		/// leave IL_0005 (cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationVBWithReturn(IfInstruction inst)
 		{
@@ -279,7 +280,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (!DelegateConstruction.MatchDelegateConstruction(delegateConstruction, out _, out _, out _, true))
 				return false;
 			context.Step("CachedDelegateInitializationVBWithReturn", inst);
-			leaveAfterIf.Value = delegateConstruction;
+			leaveAfterIf.Value = new CachedDelegate(delegateConstruction);
 			return true;
 		}
 
@@ -290,7 +291,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		/// 	stloc s(stobj delegateType(ldflda CachedAnonMethodDelegate(ldloc closure), DelegateConstruction))
 		/// }
 		/// =>
-		///	stloc s(DelegateConstruction)
+		///	stloc s(cached.delegate(DelegateConstruction))
 		/// </summary>
 		bool CachedDelegateInitializationVBWithClosure(IfInstruction inst)
 		{
@@ -322,7 +323,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			if (!DelegateConstruction.MatchDelegateConstruction(delegateConstruction, out _, out _, out _, true))
 				return false;
 			context.Step("CachedDelegateInitializationVBWithClosure", inst);
-			var stloc = new StLoc(s, delegateConstruction);
+			var stloc = new StLoc(s, new CachedDelegate(delegateConstruction));
 			inst.ReplaceWith(stloc);
 			context.EndStep(stloc);
 			return true;

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "11.0.0",
+    "version": "11.0.100-preview.7.26381.103",
     "rollForward": "major",
     "allowPrerelease": true
   },