Make Find References multi-threaded.

src/AddIns/BackendBindings/CSharpBinding/Project/Src/Parser/CSharpSymbolSearch.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.InteropServices;
+using System.Threading.Tasks;
 using ICSharpCode.Core;
 using ICSharpCode.Editor;
 using ICSharpCode.NRefactory.CSharp;
@@ -25,12 +26,11 @@ namespace CSharpBinding
 	{
 		IProject project;
 		FindReferences fr = new FindReferences();
-		IList<FindReferences.SearchScope> searchScopes;
+		IList<IFindReferenceSearchScope> searchScopes;
 		IList<string>[] interestingFileNames;
 		int workAmount;
 		double workAmountInverse;
 		Action<Reference> callback;
-		FileName currentFileName;
 		
 		public CSharpSymbolSearch(IProject project, IEntity entity)
 		{
@@ -84,40 +84,45 @@ namespace CSharpBinding
 			if (this.callback != null)
 				throw new InvalidOperationException("Cannot call FindReferences() twice");
 			this.callback = callback;
-			fr.ReferenceFound += OnReferenceFound;
 			
 			for (int i = 0; i < searchScopes.Count; i++) {
-				FindReferences.SearchScope searchScope = searchScopes[i];
-				foreach (string file in interestingFileNames[i]) {
-					currentFileName = FileName.Create(file);
-					FindReferencesInCurrentFile(args, searchScope);
-					args.ProgressMonitor.Progress += workAmountInverse;
-				}
+				IFindReferenceSearchScope searchScope = searchScopes[i];
+				object progressLock = new object();
+				Parallel.ForEach(
+					interestingFileNames[i],
+					new ParallelOptions {
+						MaxDegreeOfParallelism = Environment.ProcessorCount
+					},
+					delegate (string file) {
+						FindReferencesInFile(args, searchScope, FileName.Create(file));
+						lock (progressLock)
+							args.ProgressMonitor.Progress += workAmountInverse;
+					});
 			}
 		}
 		
-		void OnReferenceFound(AstNode node, ResolveResult result)
-		{
-			callback(new Reference(new DomRegion(currentFileName, node.StartLocation, node.EndLocation), result));
-		}
-		
-		void FindReferencesInCurrentFile(SymbolSearchArgs args, FindReferences.SearchScope searchScope)
+		void FindReferencesInFile(SymbolSearchArgs args, IFindReferenceSearchScope searchScope, FileName fileName)
 		{
-			ITextSource textSource = args.ParseableFileContentFinder.Create(currentFileName);
+			ITextSource textSource = args.ParseableFileContentFinder.Create(fileName);
 			if (textSource == null)
 				return;
 			if (searchScope.SearchTerm != null) {
 				// TODO: do a fast check with IndexOf()
 			}
 			
-			ParseInformation parseInfo = ParserService.Parse(currentFileName, textSource);
+			ParseInformation parseInfo = ParserService.Parse(fileName, textSource);
 			if (parseInfo == null)
 				return;
 			ParsedFile parsedFile = parseInfo.ParsedFile as ParsedFile;
 			CompilationUnit cu = parseInfo.Annotation<CompilationUnit>();
 			if (parsedFile == null || cu == null)
 				return;
-			fr.FindReferencesInFile(searchScope, parsedFile, cu, project.TypeResolveContext);
+			fr.FindReferencesInFile(
+				searchScope, parsedFile, cu, project.TypeResolveContext,
+				delegate (AstNode node, ResolveResult result) {
+					var region = new DomRegion(fileName, node.StartLocation, node.EndLocation);
+					callback(new Reference(region, result));
+				});
 		}
 	}
 }

src/AddIns/DisplayBindings/AvalonEdit.AddIn/Src/ChangeMarkerMargin.cs

@@ -200,7 +200,7 @@ namespace ICSharpCode.AvalonEdit.AddIn
 					differ.editor.Visibility = Visibility.Collapsed;
 					differ.copyButton.Visibility = Visibility.Collapsed;
 				} else {
-					var baseDocument = new TextDocument(DocumentUtilitites.GetTextSource(changeWatcher.BaseDocument));
+					var baseDocument = new TextDocument(changeWatcher.BaseDocument);
 					if (differ.editor.SyntaxHighlighting != null) {
 						var mainHighlighter = new DocumentHighlighter(baseDocument, differ.editor.SyntaxHighlighting.MainRuleSet);
 						var popupHighlighter = differ.editor.TextArea.GetService(typeof(IHighlighter)) as DocumentHighlighter;

src/Libraries/NRefactory/ICSharpCode.NRefactory/CSharp/Resolver/CompositeResolveVisitorNavigator.cs

@@ -25,8 +25,10 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 	{
 		IResolveVisitorNavigator[] navigators;
 		
-		public CompositeResolveVisitorNavigator(IResolveVisitorNavigator[] navigators)
+		public CompositeResolveVisitorNavigator(params IResolveVisitorNavigator[] navigators)
 		{
+			if (navigators == null)
+				throw new ArgumentNullException("navigators");
 			this.navigators = navigators;
 		}
 		

src/Libraries/NRefactory/ICSharpCode.NRefactory/CSharp/Resolver/FindReferenceSearchScope.cs

@@ -0,0 +1,51 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team
+// 
+// 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.
+
+using System;
+using ICSharpCode.NRefactory.TypeSystem;
+
+namespace ICSharpCode.NRefactory.CSharp.Resolver
+{
+	/// <summary>
+	/// Represents a scope in which references are searched.
+	/// </summary>
+	public interface IFindReferenceSearchScope
+	{
+		/// <summary>
+		/// Gets the search term. Only files that contain this identifier need to be parsed.
+		/// Can return null if all files need to be parsed.
+		/// </summary>
+		string SearchTerm { get; }
+		
+		/// <summary>
+		/// Gets the accessibility that defines the search scope.
+		/// </summary>
+		Accessibility Accessibility { get; }
+		
+		/// <summary>
+		/// Gets the top-level entity that defines the search scope.
+		/// </summary>
+		ITypeDefinition TopLevelTypeDefinition { get; }
+		
+		/// <summary>
+		/// Creates a navigator that can find references to this entity and reports
+		/// them to the specified callback.
+		/// </summary>
+		IResolveVisitorNavigator GetNavigator(FoundReferenceCallback callback);
+	}
+}

src/Libraries/NRefactory/ICSharpCode.NRefactory/CSharp/Resolver/FindReferences.cs

@@ -26,16 +26,13 @@ using ICSharpCode.NRefactory.Utils;
 
 namespace ICSharpCode.NRefactory.CSharp.Resolver
 {
+	public delegate void FoundReferenceCallback(AstNode astNode, ResolveResult result);
+	
 	/// <summary>
 	/// 'Find references' implementation.
 	/// </summary>
 	public class FindReferences
 	{
-		/// <summary>
-		/// Callback that is invoked whenever a reference is found.
-		/// </summary>
-		public event Action<AstNode, ResolveResult> ReferenceFound;
-		
 		#region Properties
 		/// <summary>
 		/// Gets/Sets the cancellation token.
@@ -95,28 +92,32 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		#endregion
 		
 		#region class SearchScope
-		public abstract class SearchScope : IResolveVisitorNavigator
+		abstract class SearchScope : IResolveVisitorNavigator, IFindReferenceSearchScope
 		{
 			protected string searchTerm;
 			internal Accessibility accessibility;
 			internal ITypeDefinition topLevelTypeDefinition;
-			internal FindReferences findReferences;
 			
-			/// <summary>
-			/// Gets the search term. Only files that contain this identifier need to be parsed.
-			/// Can return null if all files need to be parsed.
-			/// </summary>
-			public string SearchTerm { get { return searchTerm; } }
+			FoundReferenceCallback callback;
 			
-			/// <summary>
-			/// Gets the accessibility that defines the search scope.
-			/// </summary>
-			public Accessibility Accessibility { get { return accessibility; } }
+			IResolveVisitorNavigator IFindReferenceSearchScope.GetNavigator(FoundReferenceCallback callback)
+			{
+				SearchScope n = (SearchScope)MemberwiseClone();
+				n.callback = callback;
+				return n;
+			}
 			
-			/// <summary>
-			/// Gets the top-level entity that defines the search scope.
-			/// </summary>
-			public ITypeDefinition TopLevelTypeDefinition { get { return topLevelTypeDefinition; } }
+			string IFindReferenceSearchScope.SearchTerm {
+				get { return searchTerm; }
+			}
+			
+			Accessibility IFindReferenceSearchScope.Accessibility {
+				get { return accessibility; }
+			}
+			
+			ITypeDefinition IFindReferenceSearchScope.TopLevelTypeDefinition {
+				get { return topLevelTypeDefinition; }
+			}
 			
 			internal abstract bool CanMatch(AstNode node);
 			internal abstract bool IsMatch(ResolveResult rr);
@@ -147,15 +148,14 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 			
 			protected void ReportMatch(AstNode node, ResolveResult result)
 			{
-				var referenceFound = findReferences.ReferenceFound;
-				if (referenceFound != null)
-					referenceFound(node, result);
+				if (callback != null)
+					callback(node, result);
 			}
 		}
 		#endregion
 		
 		#region GetSearchScopes
-		public IList<SearchScope> GetSearchScopes(IEntity entity)
+		public IList<IFindReferenceSearchScope> GetSearchScopes(IEntity entity)
 		{
 			if (entity == null)
 				throw new ArgumentNullException("entity");
@@ -196,19 +196,17 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 					additionalScope = new FindChainedConstructorReferences(ctor);
 					break;
 				case EntityType.Destructor:
-					return EmptyList<SearchScope>.Instance;
+					return EmptyList<IFindReferenceSearchScope>.Instance;
 				default:
 					throw new ArgumentException("Unknown entity type " + entity.EntityType);
 			}
 			if (scope.accessibility == Accessibility.None)
 				scope.accessibility = effectiveAccessibility;
 			scope.topLevelTypeDefinition = topLevelTypeDefinition;
-			scope.findReferences = this;
 			if (additionalScope != null) {
 				if (additionalScope.accessibility == Accessibility.None)
 					additionalScope.accessibility = effectiveAccessibility;
 				additionalScope.topLevelTypeDefinition = topLevelTypeDefinition;
-				additionalScope.findReferences = this;
 				return new[] { scope, additionalScope };
 			} else {
 				return new[] { scope };
@@ -220,7 +218,7 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		/// <summary>
 		/// Gets the file names that possibly contain references to the element being searched for.
 		/// </summary>
-		public IList<string> GetInterestingFileNames(SearchScope searchScope, IEnumerable<ITypeDefinition> allTypes, ITypeResolveContext context)
+		public IList<string> GetInterestingFileNames(IFindReferenceSearchScope searchScope, IEnumerable<ITypeDefinition> allTypes, ITypeResolveContext context)
 		{
 			IEnumerable<ITypeDefinition> interestingTypes;
 			if (searchScope.TopLevelTypeDefinition != null) {
@@ -276,11 +274,13 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		/// <param name="parsedFile">The type system representation of the file being searched.</param>
 		/// <param name="compilationUnit">The compilation unit of the file being searched.</param>
 		/// <param name="context">The type resolve context to use for resolving the file.</param>
-		public void FindReferencesInFile(SearchScope searchScope, ParsedFile parsedFile, CompilationUnit compilationUnit, ITypeResolveContext context)
+		/// <param name="callback">Callback used to report the references that were found.</param>
+		public void FindReferencesInFile(IFindReferenceSearchScope searchScope, ParsedFile parsedFile, CompilationUnit compilationUnit,
+		                                 ITypeResolveContext context, FoundReferenceCallback callback)
 		{
 			if (searchScope == null)
 				throw new ArgumentNullException("searchScope");
-			FindReferencesInFile(new[] { searchScope }, parsedFile, compilationUnit, context);
+			FindReferencesInFile(new[] { searchScope }, parsedFile, compilationUnit, context, callback);
 		}
 		
 		/// <summary>
@@ -290,7 +290,9 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		/// <param name="parsedFile">The type system representation of the file being searched.</param>
 		/// <param name="compilationUnit">The compilation unit of the file being searched.</param>
 		/// <param name="context">The type resolve context to use for resolving the file.</param>
-		public void FindReferencesInFile(IList<SearchScope> searchScopes, ParsedFile parsedFile, CompilationUnit compilationUnit, ITypeResolveContext context)
+		/// <param name="callback">Callback used to report the references that were found.</param>
+		public void FindReferencesInFile(IList<IFindReferenceSearchScope> searchScopes, ParsedFile parsedFile, CompilationUnit compilationUnit,
+		                                 ITypeResolveContext context, FoundReferenceCallback callback)
 		{
 			if (searchScopes == null)
 				throw new ArgumentNullException("searchScopes");
@@ -303,16 +305,12 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 			this.CancellationToken.ThrowIfCancellationRequested();
 			if (searchScopes.Count == 0)
 				return;
-			foreach (SearchScope scope in searchScopes) {
-				if (scope.findReferences != this)
-					throw new ArgumentException("Cannot use a search scope that was created by another FindReferences instance");
-			}
 			using (var ctx = context.Synchronize()) {
 				IResolveVisitorNavigator navigator;
 				if (searchScopes.Count == 1)
-					navigator = searchScopes[0];
+					navigator = searchScopes[0].GetNavigator(callback);
 				else
-					navigator = new CompositeResolveVisitorNavigator(searchScopes.ToArray());
+					navigator = new CompositeResolveVisitorNavigator(searchScopes.Select(s => s.GetNavigator(callback)).ToArray());
 				navigator = new DetectSkippableNodesNavigator(navigator, compilationUnit);
 				CSharpResolver resolver = new CSharpResolver(ctx, this.CancellationToken);
 				ResolveVisitor v = new ResolveVisitor(resolver, parsedFile, navigator);

src/Libraries/NRefactory/ICSharpCode.NRefactory/ICSharpCode.NRefactory.csproj

@@ -104,6 +104,7 @@
     <Compile Include="CSharp\Resolver\DetectSkippableNodesNavigator.cs" />
     <Compile Include="CSharp\Resolver\FindReferencedEntities.cs" />
     <Compile Include="CSharp\Resolver\FindReferences.cs" />
+    <Compile Include="CSharp\Resolver\FindReferenceSearchScope.cs" />
     <Compile Include="CSharp\Resolver\Log.cs" />
     <Compile Include="CSharp\Resolver\OperatorResolveResult.cs" />
     <Compile Include="CSharp\Resolver\ConversionResolveResult.cs" />

src/Main/Base/Project/Src/Services/RefactoringService/FindReferenceService.cs

@@ -50,8 +50,20 @@ namespace ICSharpCode.SharpDevelop.Refactoring
 			return symbolSearches;
 		}
 		
+		/// <summary>
+		/// Finds all references to the specified entity.
+		/// The results are reported using the callback.
+		/// FindReferences may internally use parallelism, and may invoke the callback on multiple
+		/// threads in parallel.
+		/// </summary>
 		public static void FindReferences(IEntity entity, IProgressMonitor progressMonitor, Action<Reference> callback)
 		{
+			if (entity == null)
+				throw new ArgumentNullException("entity");
+			if (progressMonitor == null)
+				throw new ArgumentNullException("progressMonitor");
+			if (callback == null)
+				throw new ArgumentNullException("callback");
 			if (ParserService.LoadSolutionProjectsThreadRunning) {
 				progressMonitor.ShowingDialog = true;
 				MessageService.ShowMessage("${res:SharpDevelop.Refactoring.LoadSolutionProjectsThreadRunning}");

src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs

@@ -512,7 +512,7 @@ namespace ICSharpCode.SharpDevelop.Refactoring
 			string entityName = (entity.DeclaringTypeDefinition != null ? entity.DeclaringTypeDefinition.Name + "." + entity.Name : entity.Name);
 			using (AsynchronousWaitDialog monitor = AsynchronousWaitDialog.ShowWaitDialog("${res:SharpDevelop.Refactoring.FindReferences}", true)) {
 				List<Reference> references = new List<Reference>();
-				FindReferenceService.FindReferences(entity, monitor, references.Add);
+				FindReferenceService.FindReferences(entity, monitor, r => { lock (references) references.Add(r); });
 				FindReferencesAndRenameHelper.ShowAsSearchResults(
 					StringParser.Parse("${res:SharpDevelop.Refactoring.ReferencesTo}",
 					                   new StringTagPair("Name", entityName)),