DeltaBinder is another top allocation in C# typing traces (0.6%)

Made Binder concrete and eliminated DeltaBinder if the containingMemberOrLambda was null. (changeset 1215712)

Src/Compilers/CSharp/Source/Binder/Binder.QueryTranslationState.cs

@@ -4,11 +4,10 @@
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         private class QueryTranslationState
         {

Src/Compilers/CSharp/Source/Binder/Binder.QueryUnboundLambdaState.cs

@@ -5,11 +5,10 @@
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         delegate BoundBlock LambdaBodyResolver(LambdaSymbol lambdaSymbol, ExecutableCodeBinder lambdaBodyBinder, DiagnosticBag diagnostics);
 

Src/Compilers/CSharp/Source/Binder/Binder.RangeVariableMap.cs

@@ -3,12 +3,10 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// We represent the set of query variables in scope at a particular point by a RangeVariableMap.

Src/Compilers/CSharp/Source/Binder/Binder.WithQueryLambdaParametersBinder.cs

@@ -5,12 +5,11 @@
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         // A binder that finds query variables (BoundRangeVariableSymbol) and can bind them
         // to the appropriate rewriting involving lambda parameters when transparent identifiers are involved.

Src/Compilers/CSharp/Source/Binder/Binder.cs

@@ -14,9 +14,8 @@ namespace Microsoft.CodeAnalysis.CSharp
     /// A Binder converts names in to symbols and syntax nodes into bound trees. It is context
     /// dependent, relative to a location in source code.
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
-
         internal CSharpCompilation Compilation { get; private set; }
         private readonly Binder next;
 

Src/Compilers/CSharp/Source/Binder/Binder_AnonymousTypes.cs

@@ -2,11 +2,8 @@
 
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.Linq;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
-using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
@@ -14,7 +11,7 @@ namespace Microsoft.CodeAnalysis.CSharp
     /// This portion of the binder converts a AnonymousObjectCreationExpressionSyntax into 
     /// a bound anonymous object creation node
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         private BoundExpression BindAnonymousObjectCreation(AnonymousObjectCreationExpressionSyntax node, DiagnosticBag diagnostics)
         {

Src/Compilers/CSharp/Source/Binder/Binder_Attributes.cs

@@ -7,12 +7,11 @@
 using System.Linq;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         #region Bind All Attributes
 

Src/Compilers/CSharp/Source/Binder/Binder_Await.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  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.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
     /// <summary>
     /// This portion of the binder converts an AwaitExpressionSyntax into a BoundExpression
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         private BoundExpression BindAwait(PrefixUnaryExpressionSyntax node, DiagnosticBag diagnostics)
         {

Src/Compilers/CSharp/Source/Binder/Binder_Constraints.cs

@@ -5,12 +5,11 @@
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// Return a collection of bound constraint clauses indexed by type parameter

Src/Compilers/CSharp/Source/Binder/Binder_Conversions.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections.Generic;
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
 
         protected BoundExpression CreateConversion(

Src/Compilers/CSharp/Source/Binder/Binder_Crefs.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using System.Linq;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Roslyn.Utilities;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         internal ImmutableArray<Symbol> BindCref(CrefSyntax syntax, out Symbol ambiguityWinner, DiagnosticBag diagnostics)
         {

Src/Compilers/CSharp/Source/Binder/Binder_Expressions.cs

@@ -16,7 +16,7 @@ namespace Microsoft.CodeAnalysis.CSharp
     /// <summary>
     /// This portion of the binder converts an <see cref="ExpressionSyntax"/> into a <see cref="BoundExpression"/>.
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// Determines whether "this" reference is available within the current context.

Src/Compilers/CSharp/Source/Binder/Binder_Flags.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System.Diagnostics;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// Represents a small change from the enclosing/next binder.
-        /// Can specify a BindingLocation and/or a ContainingMemberOrLambda.
+        /// Can specify a BindingLocation and a ContainingMemberOrLambda.
         /// </summary>
-        private sealed class DeltaBinder : Binder
+        private sealed class BinderWithContainingMemberOrLambda : Binder
         {
             private readonly Symbol containingMemberOrLambda;
 
-            internal DeltaBinder(BinderFlags location, Binder next, Symbol containingMemberOrLambda = null)
-                : base(next, location)
+            internal BinderWithContainingMemberOrLambda(Binder next, Symbol containingMemberOrLambda)
+                : base(next)
             {
-                this.containingMemberOrLambda = containingMemberOrLambda ?? Next.ContainingMemberOrLambda;
+                this.containingMemberOrLambda = containingMemberOrLambda;
+            }
+
+            internal BinderWithContainingMemberOrLambda(Binder next, BinderFlags flags, Symbol containingMemberOrLambda)
+                : base(next, flags)
+            {
+                this.containingMemberOrLambda = containingMemberOrLambda;
             }
 
             internal override Symbol ContainingMemberOrLambda
@@ -31,20 +36,20 @@ internal Binder WithFlags(BinderFlags flags)
         {
             return this.Flags == flags
                 ? this
-                : new DeltaBinder(flags, this);
+                : new Binder(this, flags);
         }
 
         internal Binder WithAdditionalFlags(BinderFlags flags)
         {
             return this.Flags.Includes(flags)
                 ? this
-                : new DeltaBinder(this.Flags | flags, this);
+                : new Binder(this, this.Flags | flags);
         }
 
         internal Binder WithContainingMemberOrLambda(Symbol containing)
         {
             Debug.Assert((object)containing != null);
-            return new DeltaBinder(this.Flags, this, containing);
+            return new BinderWithContainingMemberOrLambda(this, containing);
         }
 
         /// <remarks>
@@ -54,14 +59,14 @@ internal Binder WithContainingMemberOrLambda(Symbol containing)
         internal Binder WithAdditionalFlagsAndContainingMemberOrLambda(BinderFlags flags, Symbol containing)
         {
             Debug.Assert((object)containing != null);
-            return new DeltaBinder(this.Flags | flags, this, containing);
+            return new BinderWithContainingMemberOrLambda(this, this.Flags | flags, containing);
         }
 
         internal Binder WithUnsafeRegionIfNecessary(SyntaxTokenList modifiers)
         {
             return (this.Flags.Includes(BinderFlags.UnsafeRegion) || !modifiers.Any(SyntaxKind.UnsafeKeyword))
                 ? this
-                : new DeltaBinder(this.Flags | BinderFlags.UnsafeRegion, this);
+                : new Binder(this, this.Flags | BinderFlags.UnsafeRegion);
         }
 
         internal Binder WithCheckedOrUncheckedRegion(bool @checked)
@@ -73,7 +78,7 @@ internal Binder WithCheckedOrUncheckedRegion(bool @checked)
 
             return this.Flags.Includes(added)
                 ? this
-                : new DeltaBinder((this.Flags & ~removed) | added, this);
+                : new Binder(this, (this.Flags & ~removed) | added);
         }
     }
 }

Src/Compilers/CSharp/Source/Binder/Binder_Lambda.cs

@@ -5,11 +5,10 @@
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         // An anonymous function can be of the form:
         // 

Src/Compilers/CSharp/Source/Binder/Binder_NameConflicts.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  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.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using System.Linq;
-using System.Text;
 using System.Threading;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// <para>Once a simple name has been bound to a particular symbol, we need to ensure that symbol is the

Src/Compilers/CSharp/Source/Binder/Binder_Operators.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  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.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         private BoundExpression BindCompoundAssignment(BinaryExpressionSyntax node, DiagnosticBag diagnostics)
         {

Src/Compilers/CSharp/Source/Binder/Binder_Query.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
 using System.Linq;
@@ -7,14 +8,13 @@
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
     /// <summary>
     /// This portion of the binder converts a QueryExpressionSyntax into a BoundExpression
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         const string transparentIdentifierPrefix = "<>h__TransparentIdentifier";
 

Src/Compilers/CSharp/Source/Binder/Binder_QueryErrors.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
-using System.Linq;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
-using Roslyn.Utilities;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
     /// <summary>
     /// This portion of the binder reports errors arising from resolving queries.
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// This is a clone of the Dev10 logic for reporting query errors.

Src/Compilers/CSharp/Source/Binder/Binder_Statements.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  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.Generic;
 using System.Collections.Immutable;
-using System.Linq;
 using System.Diagnostics;
+using System.Linq;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
-using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
     /// <summary>
     /// This portion of the binder converts StatementSyntax nodes into BoundStatements
     /// </summary>
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// This is the set of parameters and local variables that were used as arguments to 

Src/Compilers/CSharp/Source/Binder/Binder_Symbols.cs

@@ -8,13 +8,11 @@
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.RuntimeMembers;
-using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
-using Cci = Microsoft.Cci;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         /// <summary>
         /// Binds the type for the syntax taking into account possibility of "var" type.

Src/Compilers/CSharp/Source/Binder/Binder_Unsafe.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System.Diagnostics;
-using System.Threading;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 
 namespace Microsoft.CodeAnalysis.CSharp

Src/Compilers/CSharp/Source/Binder/Binder_XmlNameAttribute.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  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.Immutable;
 using System.Diagnostics;
-using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
-using Roslyn.Utilities;
 using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {
-    internal abstract partial class Binder
+    internal partial class Binder
     {
         // Diagnostics are generated in a separate pass when we emit.
         internal ImmutableArray<Symbol> BindXmlNameAttribute(XmlNameAttributeSyntax syntax, ref HashSet<DiagnosticInfo> useSiteDiagnostics)

Src/Compilers/CSharp/Source/Binder/ConstantFieldsInProgressBinder.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
-using Microsoft.CodeAnalysis.CSharp.Symbols;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 namespace Microsoft.CodeAnalysis.CSharp
 {
     /// <summary>

Src/Compilers/CSharp/Source/Binder/EarlyWellKnownAttributeBinder.cs

@@ -4,7 +4,6 @@
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {

Src/Compilers/CSharp/Source/Binder/TypeofBinder.cs

 // Copyright (c) Microsoft Open Technologies, Inc.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System.Collections.Generic;
-using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CSharp
 {