Remove AnalyzerExtensions.settingsCache

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers/AnalyzerExtensions.cs

@@ -6,7 +6,6 @@ namespace StyleCop.Analyzers
     using System;
     using System.Collections.Concurrent;
     using System.Collections.Immutable;
-    using System.Runtime.CompilerServices;
     using System.Threading;
     using Microsoft.CodeAnalysis;
     using Microsoft.CodeAnalysis.Diagnostics;
@@ -27,9 +26,6 @@ internal static class AnalyzerExtensions
         private static Tuple<WeakReference<Compilation>, ConcurrentDictionary<SyntaxTree, bool>> generatedHeaderCache
             = Tuple.Create(new WeakReference<Compilation>(null), default(ConcurrentDictionary<SyntaxTree, bool>));
 
-        private static Tuple<WeakReference<Compilation>, StrongBox<StyleCopSettings>> settingsCache
-            = Tuple.Create(new WeakReference<Compilation>(null), default(StrongBox<StyleCopSettings>));
-
         /// <summary>
         /// Register an action to be executed at completion of parsing of a code document. A syntax tree action reports
         /// diagnostics about the <see cref="SyntaxTree"/> of a document.
@@ -96,40 +92,6 @@ public static ConcurrentDictionary<SyntaxTree, bool> GetOrCreateGeneratedDocumen
             return headerCache.Item2;
         }
 
-        /// <summary>
-        /// Gets a <see cref="StrongBox{T}"/> which can store a <see cref="StyleCopSettings"/> instance to improve
-        /// efficiency across multiple analyzers which examine settings.
-        /// </summary>
-        /// <param name="compilation">The compilation which the cache applies to.</param>
-        /// <returns>A <see cref="StrongBox{T}"/> which can store a <see cref="StyleCopSettings"/> instance.</returns>
-        public static StrongBox<StyleCopSettings> GetOrCreateStyleCopSettingsCache(this Compilation compilation)
-        {
-            var currentSettingsCache = settingsCache;
-
-            Compilation cachedCompilation;
-            if (!currentSettingsCache.Item1.TryGetTarget(out cachedCompilation) || cachedCompilation != compilation)
-            {
-                var replacementCache = Tuple.Create(new WeakReference<Compilation>(compilation), new StrongBox<StyleCopSettings>(null));
-                while (true)
-                {
-                    var prior = Interlocked.CompareExchange(ref settingsCache, replacementCache, currentSettingsCache);
-                    if (prior == currentSettingsCache)
-                    {
-                        currentSettingsCache = replacementCache;
-                        break;
-                    }
-
-                    currentSettingsCache = prior;
-                    if (currentSettingsCache.Item1.TryGetTarget(out cachedCompilation) && cachedCompilation == compilation)
-                    {
-                        break;
-                    }
-                }
-            }
-
-            return currentSettingsCache.Item2;
-        }
-
         /// <summary>
         /// Register an action to be executed at completion of semantic analysis of a <see cref="SyntaxNode"/> with an
         /// appropriate kind. A syntax node action can report diagnostics about a <see cref="SyntaxNode"/>, and can also
@@ -222,7 +184,6 @@ public static void RegisterSyntaxNodeActionHonorExclusions<TLanguageKindEnum>(th
         {
             Compilation compilation = context.Compilation;
             ConcurrentDictionary<SyntaxTree, bool> cache = GetOrCreateGeneratedDocumentCache(compilation);
-            StrongBox<StyleCopSettings> settingsCache = GetOrCreateStyleCopSettingsCache(compilation);
 
             context.RegisterSyntaxNodeAction(
                 c =>
@@ -236,14 +197,7 @@ public static void RegisterSyntaxNodeActionHonorExclusions<TLanguageKindEnum>(th
                     // MSBuild metadata, if analyzers have access to it.
                     //// TODO: code here
 
-                    StyleCopSettings settings = settingsCache.Value;
-                    if (settings == null)
-                    {
-                        StyleCopSettings updatedSettings = SettingsHelper.GetStyleCopSettings(c.Options, c.CancellationToken);
-                        StyleCopSettings previous = Interlocked.CompareExchange(ref settingsCache.Value, updatedSettings, null);
-                        settings = previous ?? updatedSettings;
-                    }
-
+                    StyleCopSettings settings = context.GetStyleCopSettings(c.Options, c.CancellationToken);
                     action(c, settings);
                 },
                 syntaxKinds);