TypeUsedByAnalyzer: Refactoring and optimization, we now use raw metadata information whereever possible.

ILSpy/Analyzers/AnalyzerScope.cs

@@ -84,6 +84,11 @@ namespace ICSharpCode.ILSpy.Analyzers
 				.Where(x => x != null);
 		}
 
+		public DecompilerTypeSystem ConstructTypeSystem(PEFile module)
+		{
+			return new DecompilerTypeSystem(module, module.GetAssemblyResolver(assemblyListSnapshot, loadOnDemand: false));
+		}
+
 		public IEnumerable<ITypeDefinition> GetTypesInScope(CancellationToken ct)
 		{
 			if (IsLocal)
@@ -97,7 +102,7 @@ namespace ICSharpCode.ILSpy.Analyzers
 			{
 				foreach (var module in GetModulesInScope(ct))
 				{
-					var typeSystem = new DecompilerTypeSystem(module, module.GetAssemblyResolver(assemblyListSnapshot, loadOnDemand: false));
+					var typeSystem = ConstructTypeSystem(module);
 					foreach (var type in typeSystem.MainModule.TypeDefinitions)
 					{
 						yield return type;

ILSpy/Analyzers/Builtin/FindTypeInAttributeDecoder.cs

@@ -0,0 +1,158 @@
+// Copyright (c) 2022 Siegfried Pammer
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+#nullable enable
+
+using System;
+using System.Reflection.Metadata;
+
+using ICSharpCode.Decompiler;
+using ICSharpCode.Decompiler.Metadata;
+using ICSharpCode.Decompiler.TypeSystem;
+
+namespace ICSharpCode.ILSpy.Analyzers.Builtin
+{
+	public enum TokenSearchResult : byte
+	{
+		NoResult = 0,
+		Byte = PrimitiveTypeCode.Byte,
+		SByte = PrimitiveTypeCode.SByte,
+		Int16 = PrimitiveTypeCode.Int16,
+		UInt16 = PrimitiveTypeCode.UInt16,
+		Int32 = PrimitiveTypeCode.Int32,
+		UInt32 = PrimitiveTypeCode.UInt32,
+		Int64 = PrimitiveTypeCode.Int64,
+		UInt64 = PrimitiveTypeCode.UInt64,
+		IntPtr = PrimitiveTypeCode.IntPtr,
+		UIntPtr = PrimitiveTypeCode.UIntPtr,
+
+		// lowest PrimitiveTypeCode is 1
+		// highest PrimitiveTypeCode is 28 (0b0001_1100)
+		// TokenSearchResult with a PrimitiveTypeCode set is only used when decoding an enum-type.
+		// It is used for GetUnderlyingEnumType and should be masked out in all other uses.
+		// MSB = Found
+		// 127 = System.Type
+		TypeCodeMask = 0b0111_1111,
+		Found = 0b1000_0000,
+		SystemType = 127,
+	}
+
+	class FindTypeInAttributeDecoder : ICustomAttributeTypeProvider<TokenSearchResult>
+	{
+		readonly PEFile declaringModule;
+		readonly MetadataModule currentModule;
+		readonly TypeDefinitionHandle handle;
+		readonly PrimitiveTypeCode primitiveType;
+
+		/// <summary>
+		/// Constructs a FindTypeInAttributeDecoder that can be used to find <paramref name="type"/> in signatures from <paramref name="currentModule"/>.
+		/// </summary>
+		public FindTypeInAttributeDecoder(MetadataModule currentModule, ITypeDefinition type)
+		{
+			this.currentModule = currentModule;
+			this.declaringModule = type.ParentModule.PEFile ?? throw new InvalidOperationException("Cannot use MetadataModule without PEFile as context.");
+			this.handle = (TypeDefinitionHandle)type.MetadataToken;
+			this.primitiveType = type.KnownTypeCode == KnownTypeCode.None ? 0 : type.KnownTypeCode.ToPrimitiveTypeCode();
+		}
+
+		public TokenSearchResult GetPrimitiveType(PrimitiveTypeCode typeCode)
+		{
+			return typeCode == primitiveType ? TokenSearchResult.Found : 0;
+		}
+
+		public TokenSearchResult GetSystemType() => TokenSearchResult.SystemType;
+
+		public TokenSearchResult GetSZArrayType(TokenSearchResult elementType) => elementType & TokenSearchResult.Found;
+
+		public TokenSearchResult GetTypeFromDefinition(MetadataReader reader, TypeDefinitionHandle handle, byte rawTypeKind)
+		{
+			TokenSearchResult result = TokenSearchResult.NoResult;
+
+			if (handle.IsEnum(reader, out PrimitiveTypeCode underlyingType))
+			{
+				result = (TokenSearchResult)underlyingType;
+			}
+			else if (((EntityHandle)handle).IsKnownType(reader, KnownTypeCode.Type))
+			{
+				result = TokenSearchResult.SystemType;
+			}
+			if (this.handle == handle && reader == declaringModule.Metadata)
+			{
+				result |= TokenSearchResult.Found;
+			}
+			return result;
+		}
+
+		public TokenSearchResult GetTypeFromReference(MetadataReader reader, TypeReferenceHandle handle, byte rawTypeKind)
+		{
+			var t = currentModule.ResolveType(handle, default);
+			return GetResultFromResolvedType(t);
+		}
+
+		public TokenSearchResult GetTypeFromSerializedName(string name)
+		{
+			if (name == null)
+			{
+				return TokenSearchResult.NoResult;
+			}
+			try
+			{
+				IType type = ReflectionHelper.ParseReflectionName(name)
+					.Resolve(new SimpleTypeResolveContext(currentModule));
+				return GetResultFromResolvedType(type);
+			}
+			catch (ReflectionNameParseException)
+			{
+				return TokenSearchResult.NoResult;
+			}
+		}
+
+		private TokenSearchResult GetResultFromResolvedType(IType type)
+		{
+			var td = type.GetDefinition();
+			if (td == null)
+				return TokenSearchResult.NoResult;
+
+			TokenSearchResult result = TokenSearchResult.NoResult;
+			var underlyingType = td.EnumUnderlyingType?.GetDefinition();
+			if (underlyingType != null)
+			{
+				result = (TokenSearchResult)underlyingType.KnownTypeCode.ToPrimitiveTypeCode();
+			}
+			else if (td.KnownTypeCode == KnownTypeCode.Type)
+			{
+				result = TokenSearchResult.SystemType;
+			}
+			if (td.MetadataToken == this.handle && td.ParentModule.PEFile == declaringModule)
+			{
+				result |= TokenSearchResult.Found;
+			}
+			return result;
+		}
+
+		public PrimitiveTypeCode GetUnderlyingEnumType(TokenSearchResult type)
+		{
+			TokenSearchResult typeCode = type & TokenSearchResult.TypeCodeMask;
+			if (typeCode == 0 || typeCode == TokenSearchResult.SystemType)
+				throw new EnumUnderlyingTypeResolveException();
+			return (PrimitiveTypeCode)typeCode;
+		}
+
+		public bool IsSystemType(TokenSearchResult type) => (type & TokenSearchResult.TypeCodeMask) == TokenSearchResult.SystemType;
+	}
+}

ILSpy/Analyzers/Builtin/TypeUsedByAnalyzer.cs

@@ -20,8 +20,10 @@ using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
+using System.Linq;
 using System.Reflection.Metadata;
 
+using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.Disassembler;
 using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.Decompiler.TypeSystem;
@@ -39,188 +41,213 @@ namespace ICSharpCode.ILSpy.Analyzers.Builtin
 			Debug.Assert(analyzedSymbol is ITypeDefinition);
 			var analyzedType = (ITypeDefinition)analyzedSymbol;
 			var scope = context.GetScopeOf(analyzedType);
-			foreach (var type in scope.GetTypesInScope(context.CancellationToken))
+			context.SortResults = true;
+
+			return scope.GetModulesInScope(context.CancellationToken)
+				.AsParallel().AsOrdered()
+				.SelectMany(AnalyzeModuleAndFilter);
+
+			IEnumerable<ISymbol> AnalyzeModuleAndFilter(PEFile module)
 			{
-				foreach (var result in ScanType(analyzedType, type, context))
+				return AnalyzeModule(analyzedType, scope, module)
-					yield return result;
+					.Distinct()
+					.Where(s => !analyzedType.Equals((s as IEntity)?.DeclaringTypeDefinition));
 			}
 		}
 
-		IEnumerable<IEntity> ScanType(ITypeDefinition analyzedEntity, ITypeDefinition type, AnalyzerContext context)
+		static IEnumerable<ISymbol> AnalyzeModule(ITypeDefinition analyzedType, AnalyzerScope scope, PEFile module)
 		{
-			if (analyzedEntity.ParentModule.PEFile == type.ParentModule.PEFile
+			var metadata = module.Metadata;
-				&& analyzedEntity.MetadataToken == type.MetadataToken)
+			var typeSystem = scope.ConstructTypeSystem(module);
-				yield break;
+			var decoder = new FindTypeDecoder(typeSystem.MainModule, analyzedType);
+
+			//// resolve type refs
+			//int rowCount = metadata.GetTableRowCount(TableIndex.TypeRef);
+			//BitSet typeReferences = new BitSet(rowCount);
+			//for (int row = 0; row < rowCount; row++)
+			//{
+			//	var h = MetadataTokens.TypeReferenceHandle(row + 1);
+			//	typeReferences[row] = decoder.GetTypeFromReference(metadata, h, 0);
+			//}
+
+			//// resolve type specs
+			//rowCount = metadata.GetTableRowCount(TableIndex.TypeSpec);
+			//BitSet typeSpecifications = new BitSet(rowCount);
+			//for (int row = 0; row < rowCount; row++)
+			//{
+			//	var h = MetadataTokens.TypeSpecificationHandle(row + 1);
+			//	typeSpecifications[row] = decoder.GetTypeFromSpecification(metadata, default, h, 0);
+			//}
+
+			foreach (ISymbol result in FindUsesInAttributes(typeSystem, metadata, decoder, analyzedType))
+				yield return result;
+
+			foreach (var h in metadata.TypeDefinitions)
+			{
+				var td = metadata.GetTypeDefinition(h);
+				bool found = decoder.GetTypeFromEntity(metadata, td.GetBaseTypeOrNil());
+				foreach (var ih in td.GetInterfaceImplementations())
+				{
+					var ii = metadata.GetInterfaceImplementation(ih);
+					found |= decoder.GetTypeFromEntity(metadata, ii.Interface);
+				}
 
-			var visitor = new TypeDefinitionUsedVisitor(analyzedEntity, topLevelOnly: false);
+				found |= FindUsesInGenericConstraints(metadata, td.GetGenericParameters(), decoder);
+
+				if (found)
+					yield return typeSystem.MainModule.GetDefinition(h);
+			}
+
+			foreach (var h in metadata.MethodDefinitions)
+			{
+				var md = metadata.GetMethodDefinition(h);
+				var msig = md.DecodeSignature(decoder, default);
+				bool found = FindTypeDecoder.AnyInMethodSignature(msig);
+				found |= FindUsesInGenericConstraints(metadata, md.GetGenericParameters(), decoder);
+				if (found || ScanMethodBody(analyzedType, module, md, decoder))
+				{
+					var method = typeSystem.MainModule.GetDefinition(h);
+					yield return method?.AccessorOwner ?? method;
+				}
+			}
 
-			foreach (var bt in type.DirectBaseTypes)
+			foreach (var h in metadata.FieldDefinitions)
 			{
-				bt.AcceptVisitor(visitor);
+				var fd = metadata.GetFieldDefinition(h);
+				if (fd.DecodeSignature(decoder, default))
+					yield return typeSystem.MainModule.GetDefinition(h);
 			}
 
-			if (visitor.Found || ScanAttributes(visitor, type.GetAttributes()))
+			foreach (var h in metadata.PropertyDefinitions)
-				yield return type;
+			{
+				var pd = metadata.GetPropertyDefinition(h);
+				var psig = pd.DecodeSignature(decoder, default);
+				if (FindTypeDecoder.AnyInMethodSignature(psig))
+					yield return typeSystem.MainModule.GetDefinition(h);
+			}
 
-			foreach (var member in type.Members)
+			foreach (var h in metadata.EventDefinitions)
 			{
-				visitor.Found = false;
+				var ed = metadata.GetEventDefinition(h);
-				VisitMember(visitor, member, context);
+				if (decoder.GetTypeFromEntity(metadata, ed.Type))
-				if (visitor.Found)
+					yield return typeSystem.MainModule.GetDefinition(h);
-					yield return member;
 			}
 		}
 
-		bool ScanAttributes(TypeDefinitionUsedVisitor visitor, IEnumerable<IAttribute> attributes)
+		static bool FindUsesInGenericConstraints(MetadataReader metadata, GenericParameterHandleCollection collection, FindTypeDecoder decoder)
 		{
-			foreach (var attribute in attributes)
+			foreach (var h in collection)
 			{
-				foreach (var fa in attribute.FixedArguments)
+				var gp = metadata.GetGenericParameter(h);
-				{
+				foreach (var hc in gp.GetConstraints())
-					CheckAttributeValue(fa.Value);
-					if (visitor.Found)
-						return true;
-				}
-
-				foreach (var na in attribute.NamedArguments)
 				{
-					CheckAttributeValue(na.Value);
+					var gc = metadata.GetGenericParameterConstraint(hc);
-					if (visitor.Found)
+					if (decoder.GetTypeFromEntity(metadata, gc.Type))
 						return true;
 				}
 			}
 			return false;
+		}
 
-			void CheckAttributeValue(object value)
+		static IEnumerable<ISymbol> FindUsesInAttributes(DecompilerTypeSystem typeSystem, MetadataReader metadata, FindTypeDecoder decoder, ITypeDefinition analyzedType)
+		{
+			var attrDecoder = new FindTypeInAttributeDecoder(typeSystem.MainModule, analyzedType);
+			var referencedParameters = new HashSet<ParameterHandle>();
+
+			foreach (var h in metadata.CustomAttributes)
 			{
-				if (value is IType typeofType)
+				var customAttribute = metadata.GetCustomAttribute(h);
+				CustomAttributeValue<TokenSearchResult> value;
+				try
 				{
-					typeofType.AcceptVisitor(visitor);
+					value = customAttribute.DecodeValue(attrDecoder);
 				}
-				else if (value is ImmutableArray<CustomAttributeTypedArgument<IType>> arr)
+				catch (EnumUnderlyingTypeResolveException)
 				{
-					foreach (var element in arr)
+					continue;
-					{
-						CheckAttributeValue(element.Value);
-					}
 				}
-			}
+				if (AttributeAppliedToAnalyzer.IsCustomAttributeOfType(customAttribute.Constructor, metadata, decoder)
-		}
+					|| AnalyzeCustomAttributeValue(value))
-
+				{
-		void VisitMember(TypeDefinitionUsedVisitor visitor, IMember member, AnalyzerContext context)
+					if (customAttribute.Parent.Kind == HandleKind.Parameter)
-		{
-			member.DeclaringType.AcceptVisitor(visitor);
-			switch (member)
-			{
-				case IField field:
-					field.ReturnType.AcceptVisitor(visitor);
-
-					if (!visitor.Found)
-						ScanAttributes(visitor, field.GetAttributes());
-					break;
-				case IMethod method:
-					foreach (var p in method.Parameters)
-					{
-						p.Type.AcceptVisitor(visitor);
-						if (!visitor.Found)
-							ScanAttributes(visitor, p.GetAttributes());
-					}
-
-					if (!visitor.Found)
-						ScanAttributes(visitor, method.GetAttributes());
-
-					method.ReturnType.AcceptVisitor(visitor);
-
-					if (!visitor.Found)
-						ScanAttributes(visitor, method.GetReturnTypeAttributes());
-
-					foreach (var t in method.TypeArguments)
-					{
-						t.AcceptVisitor(visitor);
-					}
-
-					foreach (var t in method.TypeParameters)
-					{
-						t.AcceptVisitor(visitor);
-
-						if (!visitor.Found)
-							ScanAttributes(visitor, t.GetAttributes());
-					}
-					if (!visitor.Found)
-						visitor.Found |= ScanMethodBody(visitor.TypeDefinition, method, context.GetMethodBody(method));
-					break;
-				case IProperty property:
-					foreach (var p in property.Parameters)
 					{
-						p.Type.AcceptVisitor(visitor);
+						referencedParameters.Add((ParameterHandle)customAttribute.Parent);
 					}
-
+					else
-					if (!visitor.Found)
-						ScanAttributes(visitor, property.GetAttributes());
-
-					property.ReturnType.AcceptVisitor(visitor);
-
-					if (!visitor.Found && property.CanGet)
 					{
-						ScanAttributes(visitor, property.Getter.GetAttributes());
+						var parent = AnalyzerHelpers.GetParentEntity(typeSystem, customAttribute);
-						if (!visitor.Found)
+						if (parent != null)
-							ScanAttributes(visitor, property.Getter.GetReturnTypeAttributes());
+							yield return parent;
-						if (!visitor.Found)
-							visitor.Found |= ScanMethodBody(visitor.TypeDefinition, property.Getter, context.GetMethodBody(property.Getter));
 					}
-
+				}
-					if (!visitor.Found && property.CanSet)
+			}
+			if (referencedParameters.Count > 0)
+			{
+				foreach (var h in metadata.MethodDefinitions)
+				{
+					var md = metadata.GetMethodDefinition(h);
+					foreach (var p in md.GetParameters())
 					{
-						ScanAttributes(visitor, property.Setter.GetAttributes());
+						if (referencedParameters.Contains(p))
-						if (!visitor.Found)
+						{
-							ScanAttributes(visitor, property.Setter.GetReturnTypeAttributes());
+							var method = typeSystem.MainModule.ResolveMethod(h, default);
-						if (!visitor.Found)
+							if (method != null)
-							visitor.Found |= ScanMethodBody(visitor.TypeDefinition, property.Setter, context.GetMethodBody(property.Setter));
+							{
+								if (method.IsAccessor)
+									yield return method.AccessorOwner;
+								else
+									yield return method;
+							}
+							break;
+						}
 					}
+				}
+			}
 
-					break;
+		}
-				case IEvent @event:
-					@event.ReturnType.AcceptVisitor(visitor);
 
-					if (!visitor.Found && @event.CanAdd)
+		private static bool AnalyzeCustomAttributeValue(CustomAttributeValue<TokenSearchResult> attribute)
-					{
+		{
-						ScanAttributes(visitor, @event.AddAccessor.GetAttributes());
+			foreach (var fa in attribute.FixedArguments)
-						if (!visitor.Found)
+			{
-							ScanAttributes(visitor, @event.AddAccessor.GetReturnTypeAttributes());
+				if (CheckAttributeValue(fa.Value))
-						if (!visitor.Found)
+					return true;
-							visitor.Found |= ScanMethodBody(visitor.TypeDefinition, @event.AddAccessor, context.GetMethodBody(@event.AddAccessor));
+			}
-					}
 
-					if (!visitor.Found && @event.CanRemove)
+			foreach (var na in attribute.NamedArguments)
-					{
+			{
-						ScanAttributes(visitor, @event.RemoveAccessor.GetAttributes());
+				if (CheckAttributeValue(na.Value))
-						if (!visitor.Found)
+					return true;
-							ScanAttributes(visitor, @event.RemoveAccessor.GetReturnTypeAttributes());
+			}
-						if (!visitor.Found)
+			return false;
-							visitor.Found |= ScanMethodBody(visitor.TypeDefinition, @event.RemoveAccessor, context.GetMethodBody(@event.RemoveAccessor));
-					}
 
-					if (!visitor.Found && @event.CanInvoke)
+			bool CheckAttributeValue(object value)
+			{
+				if (value is TokenSearchResult typeofType)
+				{
+					if ((typeofType & TokenSearchResult.Found) != 0)
+						return true;
+				}
+				else if (value is ImmutableArray<CustomAttributeTypedArgument<IType>> arr)
+				{
+					foreach (var element in arr)
 					{
-						ScanAttributes(visitor, @event.InvokeAccessor.GetAttributes());
+						if (CheckAttributeValue(element.Value))
-						if (!visitor.Found)
+							return true;
-							ScanAttributes(visitor, @event.InvokeAccessor.GetReturnTypeAttributes());
-						if (!visitor.Found)
-							visitor.Found |= ScanMethodBody(visitor.TypeDefinition, @event.InvokeAccessor, context.GetMethodBody(@event.InvokeAccessor));
 					}
+				}
 
-					break;
+				return false;
 			}
 		}
 
-		bool ScanMethodBody(ITypeDefinition analyzedType, IMethod method, MethodBodyBlock methodBody)
+		static bool ScanMethodBody(ITypeDefinition analyzedType, PEFile module, in MethodDefinition md, FindTypeDecoder decoder)
 		{
-			if (methodBody == null)
+			if (!md.HasBody())
 				return false;
 
-			var module = (MetadataModule)method.ParentModule;
+			var methodBody = module.Reader.GetMethodBody(md.RelativeVirtualAddress);
-			var metadata = module.PEFile.Metadata;
+			var metadata = module.Metadata;
-			var decoder = new FindTypeDecoder(module, analyzedType);
 
 			if (!methodBody.LocalSignature.IsNil)
 			{