Fix #2092: aggressively inline code in compiler-generated lambdas and…

… expression trees.
icsharpcode · Jun 18, 2021 · 8eafbb3 · 8eafbb3
1 parent 164c888
commit 8eafbb3
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Showing 3 changed files with 22 additions and 8 deletions.
diff --git a/ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs b/ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs
@@ -419,6 +419,12 @@ static bool IsClosureType(SRM.TypeDefinition type, MetadataReader metadata)
 				return true;
 			return type.BaseType.IsKnownType(metadata, KnownTypeCode.Object) && !type.GetInterfaceImplementations().Any();
 		}
+
+		internal static bool IsTransparentIdentifier(string identifier)
+		{
+			return identifier.StartsWith("<>", StringComparison.Ordinal)
+				&& (identifier.Contains("TransparentIdentifier") || identifier.Contains("TranspIdent"));
+		}
 		#endregion
 
 		static PEFile LoadPEFile(string fileName, DecompilerSettings settings)

diff --git a/ICSharpCode.Decompiler/CSharp/Transforms/CombineQueryExpressions.cs b/ICSharpCode.Decompiler/CSharp/Transforms/CombineQueryExpressions.cs
@@ -103,14 +103,9 @@ void CombineQueries(AstNode node, Dictionary<string, object> fromOrLetIdentifier
 			}
 		};
 
-		bool IsTransparentIdentifier(string identifier)
-		{
-			return identifier.StartsWith("<>", StringComparison.Ordinal) && (identifier.Contains("TransparentIdentifier") || identifier.Contains("TranspIdent"));
-		}
-
 		bool TryRemoveTransparentIdentifier(QueryExpression query, QueryFromClause fromClause, QueryExpression innerQuery, Dictionary<string, object> letClauses)
 		{
-			if (!IsTransparentIdentifier(fromClause.Identifier))
+			if (!CSharpDecompiler.IsTransparentIdentifier(fromClause.Identifier))
 				return false;
 			QuerySelectClause selectClause = innerQuery.Clauses.Last() as QuerySelectClause;
 			Match match = selectTransparentIdentifierPattern.Match(selectClause);
@@ -174,7 +169,7 @@ void RemoveTransparentIdentifierReferences(AstNode node, Dictionary<string, obje
 			if (mre != null)
 			{
 				IdentifierExpression ident = mre.Target as IdentifierExpression;
-				if (ident != null && IsTransparentIdentifier(ident.Identifier))
+				if (ident != null && CSharpDecompiler.IsTransparentIdentifier(ident.Identifier))
 				{
 					IdentifierExpression newIdent = new IdentifierExpression(mre.MemberName);
 					mre.TypeArguments.MoveTo(newIdent.TypeArguments);

diff --git a/ICSharpCode.Decompiler/IL/Transforms/ILInlining.cs b/ICSharpCode.Decompiler/IL/Transforms/ILInlining.cs
@@ -71,7 +71,7 @@ internal static InliningOptions OptionsForBlock(Block block, int pos, ILTransfor
 			{
 				var function = block.Ancestors.OfType<ILFunction>().FirstOrDefault();
 				var inst = block.Instructions[pos];
-				if (IsInConstructorInitializer(function, inst))
+				if (IsInConstructorInitializer(function, inst) || PreferExpressionsOverStatements(function))
 					options |= InliningOptions.Aggressive;
 			}
 			if (!context.Settings.UseRefLocalsForAccurateOrderOfEvaluation)
@@ -81,6 +81,19 @@ internal static InliningOptions OptionsForBlock(Block block, int pos, ILTransfor
 			return options;
 		}
 
+		static bool PreferExpressionsOverStatements(ILFunction function)
+		{
+			switch (function.Kind)
+			{
+				case ILFunctionKind.Delegate:
+					return function.Parameters.Any(p => CSharp.CSharpDecompiler.IsTransparentIdentifier(p.Name));
+				case ILFunctionKind.ExpressionTree:
+					return true;
+				default:
+					return false;
+			}
+		}
+
 		public static bool InlineAllInBlock(ILFunction function, Block block, ILTransformContext context)
 		{
 			bool modified = false;