Merge pull request #39394 from mavasani/ReuseSemanticModel

Re-use semantic model when attempting to compute suppress message att…

src/Compilers/Core/Portable/Diagnostic/Diagnostic.cs

@@ -341,7 +341,10 @@ public SuppressionInfo GetSuppressionInfo(Compilation compilation)
 
             AttributeData attribute;
             var suppressMessageState = new SuppressMessageAttributeState(compilation);
-            if (!suppressMessageState.IsDiagnosticSuppressed(this, out attribute))
+            if (!suppressMessageState.IsDiagnosticSuppressed(
+                    this,
+                    getSemanticModel: (compilation, tree) => compilation.GetSemanticModel(tree),
+                    out attribute))
             {
                 attribute = null;
             }

src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerDriver.cs

@@ -309,7 +309,7 @@ private void Initialize(AnalyzerExecutor analyzerExecutor, DiagnosticQueue diagn
             var analyzerExecutor = AnalyzerExecutor.Create(
                 compilation, analysisOptions.Options ?? AnalyzerOptions.Empty, addNotCategorizedDiagnosticOpt, newOnAnalyzerException, analysisOptions.AnalyzerExceptionFilter,
                 IsCompilerAnalyzer, AnalyzerManager, ShouldSkipAnalysisOnGeneratedCode, ShouldSuppressGeneratedCodeDiagnostic, IsGeneratedOrHiddenCodeLocation, IsAnalyzerSuppressedForTree, GetAnalyzerGate,
-                getSemanticModel: tree => CurrentCompilationData.GetOrCreateCachedSemanticModel(tree, compilation, cancellationToken),
+                getSemanticModel: GetOrCreateSemanticModel,
                 analysisOptions.LogAnalyzerExecutionTime, addCategorizedLocalDiagnosticOpt, addCategorizedNonLocalDiagnosticOpt, s => _programmaticSuppressions.Add(s), cancellationToken);
 
             Initialize(analyzerExecutor, diagnosticQueue, compilationData, cancellationToken);
@@ -649,7 +649,7 @@ public async Task<ImmutableArray<Diagnostic>> GetDiagnosticsAsync(Compilation co
             Diagnostic d;
             while (DiagnosticQueue.TryDequeue(out d))
             {
-                d = suppressMessageState.ApplySourceSuppressions(d);
+                d = suppressMessageState.ApplySourceSuppressions(d, GetOrCreateSemanticModel);
                 if (reportSuppressedDiagnostics || !d.IsSuppressed)
                 {
                     allDiagnostics.Add(d);
@@ -659,6 +659,12 @@ public async Task<ImmutableArray<Diagnostic>> GetDiagnosticsAsync(Compilation co
             return allDiagnostics.ToReadOnlyAndFree();
         }
 
+        private SemanticModel GetOrCreateSemanticModel(SyntaxTree tree)
+            => GetOrCreateSemanticModel(AnalyzerExecutor.Compilation, tree);
+
+        private SemanticModel GetOrCreateSemanticModel(Compilation compilation, SyntaxTree tree)
+            => CurrentCompilationData.GetOrCreateCachedSemanticModel(tree, compilation, AnalyzerExecutor.CancellationToken);
+
         public void ApplyProgrammaticSuppressions(DiagnosticBag reportedDiagnostics, Compilation compilation)
         {
             Debug.Assert(!reportedDiagnostics.IsEmptyWithoutResolution);
@@ -817,11 +823,15 @@ public ImmutableArray<Diagnostic> DequeueNonLocalDiagnosticsAndApplySuppressions
 
         private ImmutableArray<Diagnostic> FilterDiagnosticsSuppressedInSourceOrByAnalyzers(ImmutableArray<Diagnostic> diagnostics, Compilation compilation)
         {
-            diagnostics = FilterDiagnosticsSuppressedInSource(diagnostics, compilation, CurrentCompilationData.SuppressMessageAttributeState);
+            diagnostics = FilterDiagnosticsSuppressedInSource(diagnostics, compilation, CurrentCompilationData.SuppressMessageAttributeState, GetOrCreateSemanticModel);
             return ApplyProgrammaticSuppressions(diagnostics, compilation);
         }
 
-        private static ImmutableArray<Diagnostic> FilterDiagnosticsSuppressedInSource(ImmutableArray<Diagnostic> diagnostics, Compilation compilation, SuppressMessageAttributeState suppressMessageState)
+        private static ImmutableArray<Diagnostic> FilterDiagnosticsSuppressedInSource(
+            ImmutableArray<Diagnostic> diagnostics,
+            Compilation compilation,
+            SuppressMessageAttributeState suppressMessageState,
+            Func<Compilation, SyntaxTree, SemanticModel> getSemanticModel)
         {
             if (diagnostics.IsEmpty)
             {
@@ -837,7 +847,7 @@ private static ImmutableArray<Diagnostic> FilterDiagnosticsSuppressedInSource(Im
                 DiagnosticAnalysisContextHelpers.VerifyDiagnosticLocationsInCompilation(diagnostics[i], compilation);
 #endif
 
-                var diagnostic = suppressMessageState.ApplySourceSuppressions(diagnostics[i]);
+                var diagnostic = suppressMessageState.ApplySourceSuppressions(diagnostics[i], getSemanticModel);
                 if (!reportSuppressedDiagnostics && diagnostic.IsSuppressed)
                 {
                     // Diagnostic suppressed in source.

src/Compilers/Core/Portable/DiagnosticAnalyzer/CompilationWithAnalyzers.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
@@ -1149,7 +1150,13 @@ public static IEnumerable<Diagnostic> GetEffectiveDiagnostics(ImmutableArray<Dia
 
         private static IEnumerable<Diagnostic> GetEffectiveDiagnosticsImpl(ImmutableArray<Diagnostic> diagnostics, Compilation compilation)
         {
+            if (diagnostics.IsEmpty)
+            {
+                yield break;
+            }
+
             var suppressMessageState = new SuppressMessageAttributeState(compilation);
+            var semanticModelsByTree = new Dictionary<SyntaxTree, SemanticModel>();
             foreach (var diagnostic in diagnostics)
             {
                 if (diagnostic != null)
@@ -1157,10 +1164,21 @@ private static IEnumerable<Diagnostic> GetEffectiveDiagnosticsImpl(ImmutableArra
                     var effectiveDiagnostic = compilation.Options.FilterDiagnostic(diagnostic);
                     if (effectiveDiagnostic != null)
                     {
-                        yield return suppressMessageState.ApplySourceSuppressions(effectiveDiagnostic);
+                        yield return suppressMessageState.ApplySourceSuppressions(effectiveDiagnostic, getSemanticModel);
                     }
                 }
             }
+
+            SemanticModel getSemanticModel(Compilation compilation, SyntaxTree tree)
+            {
+                if (!semanticModelsByTree.TryGetValue(tree, out var model))
+                {
+                    model = compilation.GetSemanticModel(tree);
+                    semanticModelsByTree.Add(tree, model);
+                }
+
+                return model;
+            }
         }
 
         /// <summary>

src/Compilers/Core/Portable/DiagnosticAnalyzer/SuppressMessageAttributeState.cs

@@ -99,7 +99,7 @@ internal SuppressMessageAttributeState(Compilation compilation)
             _localSuppressionsBySymbol = new ConcurrentDictionary<ISymbol, ImmutableDictionary<string, SuppressMessageInfo>>();
         }
 
-        public Diagnostic ApplySourceSuppressions(Diagnostic diagnostic, ISymbol symbolOpt = null)
+        public Diagnostic ApplySourceSuppressions(Diagnostic diagnostic, Func<Compilation, SyntaxTree, SemanticModel> getSemanticModel, ISymbol symbolOpt = null)
         {
             if (diagnostic.IsSuppressed)
             {
@@ -108,7 +108,7 @@ public Diagnostic ApplySourceSuppressions(Diagnostic diagnostic, ISymbol symbolO
             }
 
             SuppressMessageInfo info;
-            if (IsDiagnosticSuppressed(diagnostic, out info))
+            if (IsDiagnosticSuppressed(diagnostic, getSemanticModel, out info))
             {
                 // Attach the suppression info to the diagnostic.
                 diagnostic = diagnostic.WithIsSuppressed(true);
@@ -117,10 +117,10 @@ public Diagnostic ApplySourceSuppressions(Diagnostic diagnostic, ISymbol symbolO
             return diagnostic;
         }
 
-        public bool IsDiagnosticSuppressed(Diagnostic diagnostic, out AttributeData suppressingAttribute)
+        public bool IsDiagnosticSuppressed(Diagnostic diagnostic, Func<Compilation, SyntaxTree, SemanticModel> getSemanticModel, out AttributeData suppressingAttribute)
         {
             SuppressMessageInfo info;
-            if (IsDiagnosticSuppressed(diagnostic, out info))
+            if (IsDiagnosticSuppressed(diagnostic, getSemanticModel, out info))
             {
                 suppressingAttribute = info.Attribute;
                 return true;
@@ -130,10 +130,10 @@ public bool IsDiagnosticSuppressed(Diagnostic diagnostic, out AttributeData supp
             return false;
         }
 
-        private bool IsDiagnosticSuppressed(Diagnostic diagnostic, out SuppressMessageInfo info)
-            => IsDiagnosticSuppressed(diagnostic.Id, diagnostic.Location, out info);
+        private bool IsDiagnosticSuppressed(Diagnostic diagnostic, Func<Compilation, SyntaxTree, SemanticModel> getSemanticModel, out SuppressMessageInfo info)
+            => IsDiagnosticSuppressed(diagnostic.Id, diagnostic.Location, getSemanticModel, out info);
 
-        private bool IsDiagnosticSuppressed(string id, Location location, out SuppressMessageInfo info)
+        private bool IsDiagnosticSuppressed(string id, Location location, Func<Compilation, SyntaxTree, SemanticModel> getSemanticModel, out SuppressMessageInfo info)
         {
             Debug.Assert(id != null);
             Debug.Assert(location != null);
@@ -148,7 +148,7 @@ private bool IsDiagnosticSuppressed(string id, Location location, out SuppressMe
             // Walk up the syntax tree checking for suppression by any declared symbols encountered
             if (location.IsInSource)
             {
-                var model = _compilation.GetSemanticModel(location.SourceTree);
+                var model = getSemanticModel(_compilation, location.SourceTree);
                 bool inImmediatelyContainingSymbol = true;
 
                 for (var node = location.SourceTree.GetRoot().FindNode(location.SourceSpan, getInnermostNodeForTie: true);