Removed InstanceReferenceKind, replaced with IsBaseReference bool value.

f1a5c845 · Fredric Silberberg · f4be7b02 · f1a5c845 · f1a5c845 · f1a5c845
35 changed file
--- a/src/Compilers/CSharp/Portable/Operations/CSharpOperationFactory.cs
+++ b/src/Compilers/CSharp/Portable/Operations/CSharpOperationFactory.cs
@@ -533,7 +533,7 @@ private IObjectOrCollectionInitializerExpression CreateBoundCollectionInitialize
        private IMemberReferenceExpression CreateBoundObjectInitializerMemberOperation(BoundObjectInitializerMember boundObjectInitializerMember)
        {
            Lazy<IOperation> instance = new Lazy<IOperation>(() => new InstanceReferenceExpression(
-                InstanceReferenceKind.Implicit,
+                false,
                _semanticModel,
                syntax: boundObjectInitializerMember.Syntax,
                type: boundObjectInitializerMember.MemberSymbol.ContainingType,
@@ -772,22 +772,22 @@ private IDefaultValueExpression CreateBoundDefaultExpressionOperation(BoundDefau

        private IInstanceReferenceExpression CreateBoundBaseReferenceOperation(BoundBaseReference boundBaseReference)
        {
-            InstanceReferenceKind instanceReferenceKind = InstanceReferenceKind.BaseClass;
+            bool isBaseReference = true;
            SyntaxNode syntax = boundBaseReference.Syntax;
            ITypeSymbol type = boundBaseReference.Type;
            Optional<object> constantValue = ConvertToOptional(boundBaseReference.ConstantValue);
            bool isImplicit = boundBaseReference.WasCompilerGenerated;
-            return new InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit);
+            return new InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit);
        }

        private IInstanceReferenceExpression CreateBoundThisReferenceOperation(BoundThisReference boundThisReference)
        {
-            InstanceReferenceKind instanceReferenceKind = boundThisReference.Syntax.Kind() == SyntaxKind.ThisExpression ? InstanceReferenceKind.Explicit : InstanceReferenceKind.Implicit;
+            bool isBaseReference = false;
            SyntaxNode syntax = boundThisReference.Syntax;
            ITypeSymbol type = boundThisReference.Type;
            Optional<object> constantValue = ConvertToOptional(boundThisReference.ConstantValue);
            bool isImplicit = boundThisReference.WasCompilerGenerated;
-            return new InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit);
+            return new InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit);
        }

        private IOperation CreateBoundAssignmentOperatorOrMemberInitializerOperation(BoundAssignmentOperator boundAssignmentOperator)
@@ -989,12 +989,12 @@ private IAddressOfExpression CreateBoundAddressOfOperatorOperation(BoundAddressO

        private IInstanceReferenceExpression CreateBoundImplicitReceiverOperation(BoundImplicitReceiver boundImplicitReceiver)
        {
-            InstanceReferenceKind instanceReferenceKind = InstanceReferenceKind.Implicit;
+            bool isBaseReference = false;
            SyntaxNode syntax = boundImplicitReceiver.Syntax;
            ITypeSymbol type = boundImplicitReceiver.Type;
            Optional<object> constantValue = ConvertToOptional(boundImplicitReceiver.ConstantValue);
            bool isImplicit = boundImplicitReceiver.WasCompilerGenerated;
-            return new InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit);
+            return new InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit);
        }

        private IConditionalAccessExpression CreateBoundConditionalAccessOperation(BoundConditionalAccess boundConditionalAccess)

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs
--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IConversionExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IConversionExpression.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.
+// 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.Linq;
@@ -1552,7 +1552,7 @@ void M1()
  IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'DType /*<bi ... *</bind>*/;')
    Variables: Local_1: Program.DType d1
    Initializer: IMethodBindingExpression: void Program.M1() (OperationKind.MethodBindingExpression, Type: Program.DType) (Syntax: 'M1')
-        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M1')
+        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M1')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -2780,7 +2780,7 @@ class C2
    Variables: Local_1: C2 c2
    Initializer: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperatorMethod: C2 C2.op_Implicit(C1 c1)) (OperationKind.ConversionExpression, Type: C2) (Syntax: 'this')
        Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: True) (MethodSymbol: C2 C2.op_Implicit(C1 c1))
-        Operand: IInstanceReferenceExpression (InstanceReferenceKind.Explicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'this')
+        Operand: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'this')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -2866,7 +2866,7 @@ class C2
            Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: True) (MethodSymbol: C2 C2.op_Implicit(System.Int64 c1))
            Operand: IConversionExpression (Explicit, TryCast: False, Unchecked) (OperatorMethod: C2 C2.op_Implicit(System.Int64 c1)) (OperationKind.ConversionExpression, Type: System.Int32) (Syntax: '(int)this')
                Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: True) (MethodSymbol: C2 C2.op_Implicit(System.Int64 c1))
-                Operand: IInstanceReferenceExpression (InstanceReferenceKind.Explicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'this')
+                Operand: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'this')
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {
                // CS0219: The variable 'i1' is assigned but its value is never used
@@ -2910,7 +2910,7 @@ class C2
    Variables: Local_1: C2 c2
    Initializer: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: C2, IsInvalid) (Syntax: 'this')
        Conversion: CommonConversion (Exists: False, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: False) (MethodSymbol: null)
-        Operand: IInstanceReferenceExpression (InstanceReferenceKind.Explicit) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'this')
+        Operand: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'this')
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {
                // CS0029: Cannot implicitly convert type 'C1' to 'C2'
@@ -2960,7 +2960,7 @@ class C3
    Variables: Local_1: C3 c3
    Initializer: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperatorMethod: C3 C3.op_Implicit(C2 c2)) (OperationKind.ConversionExpression, Type: C3) (Syntax: 'this')
        Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: True) (MethodSymbol: C3 C3.op_Implicit(C2 c2))
-        Operand: IInstanceReferenceExpression (InstanceReferenceKind.Explicit) (OperationKind.InstanceReferenceExpression, Type: C2) (Syntax: 'this')
+        Operand: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C2) (Syntax: 'this')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -5102,7 +5102,7 @@ void M1()
  IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'Action /*<b ... *</bind>*/;')
    Variables: Local_1: System.Action a
    Initializer: IMethodBindingExpression: void C1.M2() (OperationKind.MethodBindingExpression, Type: System.Action) (Syntax: '(Action)M2')
-        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
+        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -5165,7 +5165,7 @@ void M1()
  IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration, IsInvalid) (Syntax: 'Action /*<b ... *</bind>*/;')
    Variables: Local_1: System.Action a
    Initializer: IMethodBindingExpression: System.Int32 C1.M2() (OperationKind.MethodBindingExpression, Type: System.Action, IsInvalid) (Syntax: '(Action)M2')
-        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
+        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {
                // CS0407: 'int C1.M2()' has the wrong return type
@@ -5203,7 +5203,7 @@ void M1()
    Initializer: IOperation:  (OperationKind.None) (Syntax: 'new Action((Action)M2)')
        Children(1):
            IMethodBindingExpression: void C1.M2() (OperationKind.MethodBindingExpression, Type: System.Action) (Syntax: '(Action)M2')
-              Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
+              Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -5264,7 +5264,7 @@ void M1()
 IInvalidExpression (OperationKind.InvalidExpression, Type: System.Action, IsInvalid) (Syntax: 'new Action((Action)M2)')
  Children(1):
      IMethodBindingExpression: System.Int32 C1.M2() (OperationKind.MethodBindingExpression, Type: System.Action, IsInvalid) (Syntax: '(Action)M2')
-        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
+        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {
                // CS0407: 'int C1.M2()' has the wrong return type

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IDynamicObjectCreationExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IDynamicObjectCreationExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -227,7 +227,7 @@ void M(dynamic d)
      Initializers(1):
          ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = 0')
            Left: IFieldReferenceExpression: System.Int32 C.X (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'X')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'X')
            Right: ILiteralExpression (Text: 0) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;
@@ -277,7 +277,7 @@ void M(dynamic d)
      Initializers(1):
          ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = 0')
            Left: IFieldReferenceExpression: System.Int32 C.X (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'X')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'X')
            Right: ILiteralExpression (Text: 0) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IEventAssignmentExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IEventAssignmentExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -39,7 +39,7 @@ void M()
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (OperationKind.EventReferenceExpression, Type: System.EventHandler) (Syntax: 't.MyEvent')
      Instance Receiver: ILocalReferenceExpression: t (OperationKind.LocalReferenceExpression, Type: Test) (Syntax: 't')
  Handler: IMethodBindingExpression: void C.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
 ";
            var expectedDiagnostics = new[] { 
                // file.cs(6,31): warning CS0067: The event 'Test.MyEvent' is never used
@@ -117,7 +117,7 @@ void M()
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (Static) (OperationKind.EventReferenceExpression, Type: System.EventHandler) (Syntax: 'Test.MyEvent')
      Instance Receiver: null
  Handler: IMethodBindingExpression: void C.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
 ";
            var expectedDiagnostics = new[] { 
                // file.cs(6,38): warning CS0067: The event 'Test.MyEvent' is never used
@@ -157,7 +157,7 @@ void M()
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (Static) (OperationKind.EventReferenceExpression, Type: System.EventHandler) (Syntax: 'Test.MyEvent')
      Instance Receiver: null
  Handler: IMethodBindingExpression: void C.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
 ";
            var expectedDiagnostics = new[] { 
                // file.cs(6,38): warning CS0067: The event 'Test.MyEvent' is never used
@@ -243,7 +243,7 @@ void M()
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (Static) (OperationKind.EventReferenceExpression, Type: System.EventHandler, IsInvalid) (Syntax: 't.MyEvent')
      Instance Receiver: null
  Handler: IMethodBindingExpression: void C.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
 ";
            var expectedDiagnostics = new[] {                  
                // file.cs(18,19): error CS0176: Member 'Test.MyEvent' cannot be accessed with an instance reference; qualify it with a type name instead
@@ -287,7 +287,8 @@ void M()
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (OperationKind.EventReferenceExpression, Type: System.EventHandler, IsInvalid) (Syntax: 'Test.MyEvent')
      Instance Receiver: IOperation:  (OperationKind.None, IsInvalid) (Syntax: 'Test')
  Handler: IMethodBindingExpression: void C.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')";
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'Handler')
+";
            var expectedDiagnostics = new[] {                  
                // file.cs(17,19): error CS0120: An object reference is required for the non-static field, method, or property 'Test.MyEvent'
                //         /*<bind>*/Test.MyEvent += Handler/*<bind>*/;
@@ -324,9 +325,10 @@ void M()
            string expectedOperationTree = @"
 IEventAssignmentExpression (EventAdd)) (OperationKind.EventAssignmentExpression, Type: System.Void) (Syntax: 'MyEvent += Handler')
  Event Reference: IEventReferenceExpression: event System.EventHandler Test.MyEvent (OperationKind.EventReferenceExpression, Type: System.EventHandler) (Syntax: 'MyEvent')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Test) (Syntax: 'MyEvent')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Test) (Syntax: 'MyEvent')
  Handler: IMethodBindingExpression: void Test.Handler(System.Object sender, System.EventArgs e) (OperationKind.MethodBindingExpression, Type: System.EventHandler) (Syntax: 'Handler')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Test) (Syntax: 'Handler')";
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Test) (Syntax: 'Handler')
+";
            var expectedDiagnostics = new[] {                  
                      // file.cs(6,31): warning CS0067: The event 'Test.MyEvent' is never used
                      //     public event EventHandler MyEvent;

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IForLoopStatement.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IForLoopStatement.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -1209,11 +1209,11 @@ public class F
                  Initializers(2):
                      ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'i = 0')
                        Left: IFieldReferenceExpression: System.Int32 F.i (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'i')
-                            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'i')
+                            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'i')
                        Right: ILiteralExpression (Text: 0) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
                      ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.String) (Syntax: 's = ""abc""')
                        Left: IFieldReferenceExpression: System.String F.s (OperationKind.FieldReferenceExpression, Type: System.String) (Syntax: 's')
-                            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 's')
+                            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 's')
                        Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: ""abc"") (Syntax: '""abc""')
  AtLoopBottom:
      IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'f.i = f.i + 1')
@@ -1224,7 +1224,8 @@ public class F
                Left: IFieldReferenceExpression: System.Int32 F.i (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'f.i')
                    Instance Receiver: ILocalReferenceExpression: f (OperationKind.LocalReferenceExpression, Type: F) (Syntax: 'f')
                Right: ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
-  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')";
+  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
+";
            VerifyOperationTreeForTest<ForStatementSyntax>(source, expectedOperationTree);
        }


--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IIfStatement.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IIfStatement.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.CSharp.Test.Utilities;
@@ -479,7 +479,7 @@ private int A()
          Arguments(1):
              IArgument (ArgumentKind.Explicit, Matching Parameter: value) (OperationKind.Argument) (Syntax: 'A()')
                IInvocationExpression ( System.Int32 P.A()) (OperationKind.InvocationExpression, Type: System.Int32) (Syntax: 'A()')
-                  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
+                  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
                  Arguments(0)
                InConversion: null
                OutConversion: null
@@ -521,7 +521,7 @@ private void A(bool flag)
      Locals: Local_1: System.Int32 i
      IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'A(int.TryPa ... ut var i));')
        Expression: IInvocationExpression ( void P.A(System.Boolean flag)) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'A(int.TryPa ... out var i))')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
            Arguments(1):
                IArgument (ArgumentKind.Explicit, Matching Parameter: flag) (OperationKind.Argument) (Syntax: 'int.TryPars ...  out var i)')
                  IInvocationExpression (System.Boolean System.Int32.TryParse(System.String s, out System.Int32 result)) (OperationKind.InvocationExpression, Type: System.Boolean) (Syntax: 'int.TryPars ...  out var i)')
@@ -909,11 +909,11 @@ private void B()
  Condition: ILiteralExpression (OperationKind.LiteralExpression, Type: System.Boolean, Constant: True) (Syntax: 'true')
  IfTrue: IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'A();')
      Expression: IInvocationExpression ( void P.A()) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'A()')
-          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
+          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'A')
          Arguments(0)
  IfFalse: IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'B();')
      Expression: IInvocationExpression ( void P.B()) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'B()')
-          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'B')
+          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'B')
          Arguments(0)
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IInterpolatedStringExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IInterpolatedStringExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -181,14 +181,14 @@ public void M()
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: ""String "") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{x,20}')
        Expression: IFieldReferenceExpression: System.String Class.x (OperationKind.FieldReferenceExpression, Type: System.String) (Syntax: 'x')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'x')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'x')
        Alignment: ILiteralExpression (Text: 20) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 20) (Syntax: '20')
        FormatString: null
      IInterpolatedStringText (OperationKind.InterpolatedStringText) (Syntax: ' and ')
        Text: ILiteralExpression (Text:  and ) (OperationKind.LiteralExpression, Type: System.String, Constant: "" and "") (Syntax: ' and ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{y:D3}')
        Expression: IFieldReferenceExpression: System.Int32 Class.y (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'y')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'y')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'y')
        Alignment: null
        FormatString: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: ""D3"") (Syntax: ':D3')
      IInterpolatedStringText (OperationKind.InterpolatedStringText) (Syntax: ' and constant ')
@@ -228,7 +228,7 @@ public void M()
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: ""String "") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{x,y:D3}')
        Expression: IFieldReferenceExpression: System.String Class.x (OperationKind.FieldReferenceExpression, Type: System.String) (Syntax: 'x')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'x')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'x')
        Alignment: IFieldReferenceExpression: System.Int32 Class.y (Static) (OperationKind.FieldReferenceExpression, Type: System.Int32, Constant: 0) (Syntax: 'y')
            Instance Receiver: null
        FormatString: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: ""D3"") (Syntax: ':D3')
@@ -270,7 +270,7 @@ public void M()
        Text: ILiteralExpression (Text:  and ) (OperationKind.LiteralExpression, Type: System.String, Constant: "" and "") (Syntax: ' and ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{M2(y)}')
        Expression: IInvocationExpression ( System.String Class.M2(System.Int32 z)) (OperationKind.InvocationExpression, Type: System.String) (Syntax: 'M2(y)')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'M2')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'M2')
            Arguments(1):
                IArgument (ArgumentKind.Explicit, Matching Parameter: z) (OperationKind.Argument) (Syntax: 'y')
                  ILocalReferenceExpression: y (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'y')
@@ -316,7 +316,7 @@ public void M()
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: ""String "") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{M2($""{y}"")}')
        Expression: IInvocationExpression ( System.Int32 Class.M2(System.String z)) (OperationKind.InvocationExpression, Type: System.Int32) (Syntax: 'M2($""{y}"")')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'M2')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'M2')
            Arguments(1):
                IArgument (ArgumentKind.Explicit, Matching Parameter: z) (OperationKind.Argument) (Syntax: '$""{y}""')
                  IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type: System.String) (Syntax: '$""{y}""')

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_ILockStatement.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_ILockStatement.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -28,7 +28,7 @@ public void M()
            string expectedOperationTree = @"
 ILockStatement (OperationKind.LockStatement) (Syntax: 'lock (o) ... }')
  Expression: IFieldReferenceExpression: System.Object C1.o (OperationKind.FieldReferenceExpression, Type: System.Object) (Syntax: 'o')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'o')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'o')
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;
@@ -264,7 +264,7 @@ public object M2()
            string expectedOperationTree = @"
 ILockStatement (OperationKind.LockStatement) (Syntax: 'lock (M2()) ... }')
  Expression: IInvocationExpression ( System.Object C1.M2()) (OperationKind.InvocationExpression, Type: System.Object) (Syntax: 'M2()')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
      Arguments(0)
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
 ";
@@ -293,7 +293,7 @@ public void M()
            string expectedOperationTree = @"
 ILockStatement (OperationKind.LockStatement, IsInvalid) (Syntax: 'lock (M2()) ... }')
  Expression: IInvocationExpression ( void C1.M2()) (OperationKind.InvocationExpression, Type: System.Void, IsInvalid) (Syntax: 'M2()')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
      Arguments(0)
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
 ";

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IObjectCreationExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IObjectCreationExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Test.Utilities;
@@ -65,7 +65,7 @@ public void M1()
              Initializers(1):
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'Field = 2')
                    Left: IFieldReferenceExpression: System.Int32 F.Field (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'Field')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Field')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Field')
                    Right: ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
  IVariableDeclarationStatement (1 declarations) (OperationKind.VariableDeclarationStatement) (Syntax: 'var x3 = ne ... ty1 = """" };')
    IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'var x3 = ne ... ty1 = """" };')
@@ -76,7 +76,7 @@ public void M1()
              Initializers(1):
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.String) (Syntax: 'Property1 = """"')
                    Left: IPropertyReferenceExpression: System.String F.Property1 { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.String) (Syntax: 'Property1')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property1')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property1')
                    Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: """") (Syntax: '""""')
  IVariableDeclarationStatement (1 declarations) (OperationKind.VariableDeclarationStatement) (Syntax: 'var x4 = ne ... ield = 2 };')
    IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'var x4 = ne ... ield = 2 };')
@@ -87,11 +87,11 @@ public void M1()
              Initializers(2):
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.String) (Syntax: 'Property1 = """"')
                    Left: IPropertyReferenceExpression: System.String F.Property1 { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.String) (Syntax: 'Property1')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property1')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property1')
                    Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: """") (Syntax: '""""')
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'Field = 2')
                    Left: IFieldReferenceExpression: System.Int32 F.Field (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'Field')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Field')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Field')
                    Right: ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
  IVariableDeclarationStatement (1 declarations) (OperationKind.VariableDeclarationStatement) (Syntax: 'var x5 = ne ... = true } };')
    IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'var x5 = ne ... = true } };')
@@ -102,14 +102,14 @@ public void M1()
              Initializers(1):
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: B) (Syntax: 'Property2 = ... ld = true }')
                    Left: IPropertyReferenceExpression: B F.Property2 { get; set; } (OperationKind.PropertyReferenceExpression, Type: B) (Syntax: 'Property2')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property2')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property2')
                    Right: IObjectCreationExpression (Constructor: B..ctor()) (OperationKind.ObjectCreationExpression, Type: B) (Syntax: 'new B { Field = true }')
                        Arguments(0)
                        Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: B) (Syntax: '{ Field = true }')
                            Initializers(1):
                                ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Boolean) (Syntax: 'Field = true')
                                  Left: IFieldReferenceExpression: System.Boolean B.Field (OperationKind.FieldReferenceExpression, Type: System.Boolean) (Syntax: 'Field')
-                                      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: B) (Syntax: 'Field')
+                                      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: B) (Syntax: 'Field')
                                  Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.Boolean, Constant: True) (Syntax: 'true')
  IVariableDeclarationStatement (1 declarations) (OperationKind.VariableDeclarationStatement, IsInvalid) (Syntax: 'var e1 = ne ... rty2 = 1 };')
    IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration, IsInvalid) (Syntax: 'var e1 = ne ... rty2 = 1 };')
@@ -120,7 +120,7 @@ public void M1()
              Initializers(1):
                  ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: B, IsInvalid) (Syntax: 'Property2 = 1')
                    Left: IPropertyReferenceExpression: B F.Property2 { get; set; } (OperationKind.PropertyReferenceExpression, Type: B) (Syntax: 'Property2')
-                        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property2')
+                        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: F) (Syntax: 'Property2')
                    Right: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: B, IsInvalid) (Syntax: '1')
                        Conversion: CommonConversion (Exists: False, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: False) (MethodSymbol: null)
                        Operand: ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1, IsInvalid) (Syntax: '1')
@@ -178,7 +178,7 @@ public void M1(int x)
          ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.List<System.Int32>.Add(System.Int32 item)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'field')
            Arguments(1):
                IFieldReferenceExpression: System.Int32 C.field (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
+                  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
 ";
            var expectedDiagnostics = new DiagnosticDescription[] {
                // CS0649: Field 'C.field' is never assigned to, and will always have its default value 0
@@ -241,7 +241,7 @@ public void M1(int x)
                          ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.List<System.Int32>.Add(System.Int32 item)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'field')
                            Arguments(1):
                                IFieldReferenceExpression: System.Int32 C.field (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                                  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
+                                  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;

@@ -283,11 +283,11 @@ public void M(int x)
      Initializers(4):
          ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = x')
            Left: IPropertyReferenceExpression: System.Int32 Class.X { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
            Right: IParameterReferenceExpression: x (OperationKind.ParameterReferenceExpression, Type: System.Int32) (Syntax: 'x')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: 'Y = { x, y, 3 }')
            InitializedMember: IPropertyReferenceExpression: System.Collections.Generic.List<System.Int32> Class.Y { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: 'Y')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Y')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Y')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: '{ x, y, 3 }')
                Initializers(3):
                    ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.List<System.Int32>.Add(System.Int32 item)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'x')
@@ -301,7 +301,7 @@ public void M(int x)
                          ILiteralExpression (Text: 3) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 3) (Syntax: '3')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: 'Z = { { x, y } }')
            InitializedMember: IPropertyReferenceExpression: System.Collections.Generic.Dictionary<System.Int32, System.Int32> Class.Z { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: 'Z')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Z')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Z')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: '{ { x, y } }')
                Initializers(1):
                    ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.Dictionary<System.Int32, System.Int32>.Add(System.Int32 key, System.Int32 value)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: '{ x, y }')
@@ -310,14 +310,14 @@ public void M(int x)
                          ILocalReferenceExpression: y (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'y')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: Class) (Syntax: 'C = { X = field }')
            InitializedMember: IPropertyReferenceExpression: Class Class.C { get; set; } (OperationKind.PropertyReferenceExpression, Type: Class) (Syntax: 'C')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'C')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'C')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: Class) (Syntax: '{ X = field }')
                Initializers(1):
                    ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = field')
                      Left: IPropertyReferenceExpression: System.Int32 Class.X { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
+                          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
                      Right: IFieldReferenceExpression: System.Int32 Class.field (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'field')
+                          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'field')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;


--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IParameterReferenceExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IParameterReferenceExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.CSharp.Test.Utilities;
@@ -201,11 +201,11 @@ public void M(int x, int y, int z)
      Initializers(4):
          ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = x')
            Left: IPropertyReferenceExpression: System.Int32 Class.X { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
            Right: IParameterReferenceExpression: x (OperationKind.ParameterReferenceExpression, Type: System.Int32) (Syntax: 'x')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: 'Y = { x, y, 3 }')
            InitializedMember: IPropertyReferenceExpression: System.Collections.Generic.List<System.Int32> Class.Y { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: 'Y')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Y')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Y')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: System.Collections.Generic.List<System.Int32>) (Syntax: '{ x, y, 3 }')
                Initializers(3):
                    ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.List<System.Int32>.Add(System.Int32 item)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'x')
@@ -219,7 +219,7 @@ public void M(int x, int y, int z)
                          ILiteralExpression (Text: 3) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 3) (Syntax: '3')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: 'Z = { { x, y } }')
            InitializedMember: IPropertyReferenceExpression: System.Collections.Generic.Dictionary<System.Int32, System.Int32> Class.Z { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: 'Z')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Z')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'Z')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: System.Collections.Generic.Dictionary<System.Int32, System.Int32>) (Syntax: '{ { x, y } }')
                Initializers(1):
                    ICollectionElementInitializerExpression (AddMethod: void System.Collections.Generic.Dictionary<System.Int32, System.Int32>.Add(System.Int32 key, System.Int32 value)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: '{ x, y }')
@@ -228,12 +228,12 @@ public void M(int x, int y, int z)
                          IParameterReferenceExpression: y (OperationKind.ParameterReferenceExpression, Type: System.Int32) (Syntax: 'y')
          IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: Class) (Syntax: 'C = { X = z }')
            InitializedMember: IPropertyReferenceExpression: Class Class.C { get; set; } (OperationKind.PropertyReferenceExpression, Type: Class) (Syntax: 'C')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'C')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'C')
            Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: Class) (Syntax: '{ X = z }')
                Initializers(1):
                    ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.Int32) (Syntax: 'X = z')
                      Left: IPropertyReferenceExpression: System.Int32 Class.X { get; set; } (OperationKind.PropertyReferenceExpression, Type: System.Int32) (Syntax: 'X')
-                          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
+                          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
                      Right: IParameterReferenceExpression: z (OperationKind.ParameterReferenceExpression, Type: System.Int32) (Syntax: 'z')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;
@@ -361,7 +361,7 @@ public void M(int x, int y)
  Initializers(1):
      IMemberInitializerExpression (OperationKind.MemberInitializerExpression, Type: dynamic) (Syntax: 'X = { { x, y } }')
        InitializedMember: IPropertyReferenceExpression: dynamic Class.X { get; set; } (OperationKind.PropertyReferenceExpression, Type: dynamic) (Syntax: 'X')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class) (Syntax: 'X')
        Initializer: IObjectOrCollectionInitializerExpression (OperationKind.ObjectOrCollectionInitializerExpression, Type: dynamic) (Syntax: '{ { x, y } }')
            Initializers(1):
                ICollectionElementInitializerExpression (IsDynamic: True) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: '{ x, y }')

--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IUnaryOperatorExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IUnaryOperatorExpression.cs
--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_InvalidExpression.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_InvalidExpression.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.
+// 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 Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.CSharp.Test.Utilities;
@@ -63,7 +63,7 @@ void F(int x)
 ";
            string expectedOperationTree = @"
 IInvocationExpression ( void Program.F(System.Int32 x)) (OperationKind.InvocationExpression, Type: System.Void, IsInvalid) (Syntax: 'F(string.Empty)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'F')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'F')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: null) (OperationKind.Argument, IsInvalid) (Syntax: 'string.Empty')
        IFieldReferenceExpression: System.String System.String.Empty (Static) (OperationKind.FieldReferenceExpression, Type: System.String, IsInvalid) (Syntax: 'string.Empty')

--- a/src/Compilers/CSharp/Test/Semantic/Semantics/ObjectAndCollectionInitializerTests.cs
+++ b/src/Compilers/CSharp/Test/Semantic/Semantics/ObjectAndCollectionInitializerTests.cs
--- a/src/Compilers/CSharp/Test/Symbol/Symbols/AnonymousTypesSemanticsTests.cs
+++ b/src/Compilers/CSharp/Test/Symbol/Symbols/AnonymousTypesSemanticsTests.cs
@@ -409,7 +409,7 @@ void Main()
 IAnonymousObjectCreationExpression (OperationKind.AnonymousObjectCreationExpression, Type: <anonymous type: System.Func<System.Int32, System.Int32> F>) (Syntax: 'new { base.F }')
  Initializers(1):
      IFieldReferenceExpression: System.Func<System.Int32, System.Int32> ClassB.F (OperationKind.FieldReferenceExpression, Type: System.Func<System.Int32, System.Int32>) (Syntax: 'base.F')
-        Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.BaseClass) (OperationKind.InstanceReferenceExpression, Type: ClassB) (Syntax: 'base')
+        Instance Receiver: IInstanceReferenceExpression (IsBaseReference: True) (OperationKind.InstanceReferenceExpression, Type: ClassB) (Syntax: 'base')
 ";
            var expectedDiagnostics = DiagnosticDescription.None;


--- a/src/Compilers/Core/Portable/Generated/Operations.xml.Generated.cs
+++ b/src/Compilers/Core/Portable/Generated/Operations.xml.Generated.cs
@@ -2082,16 +2082,16 @@ internal sealed partial class LazyIncrementExpression : BaseIncrementExpression,
    /// </summary>
    internal sealed partial class InstanceReferenceExpression : Operation, IInstanceReferenceExpression
    {
-        public InstanceReferenceExpression(InstanceReferenceKind instanceReferenceKind, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
+        public InstanceReferenceExpression(bool isBaseReference, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
            base(OperationKind.InstanceReferenceExpression, semanticModel, syntax, type, constantValue, isImplicit)
        {
-            InstanceReferenceKind = instanceReferenceKind;
+            IsBaseReference = isBaseReference;
        }
        ///
        /// <summary>
        /// Kind of instance reference.
        /// </summary>
-        public InstanceReferenceKind InstanceReferenceKind { get; }
+        public bool IsBaseReference { get; }
        public override IEnumerable<IOperation> Children
        {
            get

--- a/src/Compilers/Core/Portable/Operations/IInstanceReferenceExpression.cs
+++ b/src/Compilers/Core/Portable/Operations/IInstanceReferenceExpression.cs
@@ -13,11 +13,10 @@ namespace Microsoft.CodeAnalysis.Semantics
    /// </remarks>
    public interface IInstanceReferenceExpression : IOperation
    {
-        ///
        /// <summary>
-        /// Kind of instance reference.
+        /// True if this is a reference to base or MyBase
        /// </summary>
-        InstanceReferenceKind InstanceReferenceKind { get; }
+        bool IsBaseReference { get; }
    }
 }

--- a/src/Compilers/Core/Portable/Operations/InstanceReferenceKind.cs
+++ b/src/Compilers/Core/Portable/Operations/InstanceReferenceKind.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.Collections.Immutable;
-
-namespace Microsoft.CodeAnalysis.Semantics
-{
-    public enum InstanceReferenceKind
-    {
-        None = 0x0,
-        /// <summary>Indicates an implicit this or Me expression.</summary>
-        Implicit = 0x1,
-        /// <summary>Indicates an explicit this or Me expression.</summary>
-        Explicit = 0x2,
-        /// <summary>Indicates an explicit base or MyBase expression.</summary>
-        BaseClass = 0x3,
-        /// <summary>Indicates an explicit MyClass expression.</summary>
-        ThisClass = 0x4
-    }
-}
-
--- a/src/Compilers/Core/Portable/Operations/OperationCloner.cs
+++ b/src/Compilers/Core/Portable/Operations/OperationCloner.cs
@@ -211,7 +211,7 @@ public override IOperation VisitSyntheticLocalReferenceExpression(ISyntheticLoca

        public override IOperation VisitInstanceReferenceExpression(IInstanceReferenceExpression operation, object argument)
        {
-            return new InstanceReferenceExpression(operation.InstanceReferenceKind, ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
+            return new InstanceReferenceExpression(operation.IsBaseReference, ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
        }

        public override IOperation VisitFieldReferenceExpression(IFieldReferenceExpression operation, object argument)

--- a/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
+++ b/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
@@ -459,7 +459,7 @@ Microsoft.CodeAnalysis.Semantics.IIncrementExpression
 Microsoft.CodeAnalysis.Semantics.IIncrementExpression.IncrementOperationKind.get -> Microsoft.CodeAnalysis.Semantics.UnaryOperationKind
 Microsoft.CodeAnalysis.Semantics.IIncrementExpression.Target.get -> Microsoft.CodeAnalysis.IOperation
 Microsoft.CodeAnalysis.Semantics.IInstanceReferenceExpression
-Microsoft.CodeAnalysis.Semantics.IInstanceReferenceExpression.InstanceReferenceKind.get -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
+Microsoft.CodeAnalysis.Semantics.IInstanceReferenceExpression.IsBaseReference.get -> bool
 Microsoft.CodeAnalysis.Semantics.IInterpolatedStringContent
 Microsoft.CodeAnalysis.Semantics.IInterpolatedStringExpression
 Microsoft.CodeAnalysis.Semantics.IInterpolatedStringExpression.Parts.get -> System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.Semantics.IInterpolatedStringContent>
@@ -594,12 +594,6 @@ Microsoft.CodeAnalysis.Semantics.IWhileUntilLoopStatement.IsWhile.get -> bool
 Microsoft.CodeAnalysis.Semantics.IWithStatement
 Microsoft.CodeAnalysis.Semantics.IWithStatement.Body.get -> Microsoft.CodeAnalysis.IOperation
 Microsoft.CodeAnalysis.Semantics.IWithStatement.Value.get -> Microsoft.CodeAnalysis.IOperation
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind.BaseClass = 3 -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind.Explicit = 2 -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind.Implicit = 1 -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind.None = 0 -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
-Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind.ThisClass = 4 -> Microsoft.CodeAnalysis.Semantics.InstanceReferenceKind
 Microsoft.CodeAnalysis.Semantics.LoopKind
 Microsoft.CodeAnalysis.Semantics.LoopKind.For = 2 -> Microsoft.CodeAnalysis.Semantics.LoopKind
 Microsoft.CodeAnalysis.Semantics.LoopKind.ForEach = 3 -> Microsoft.CodeAnalysis.Semantics.LoopKind

--- a/src/Compilers/VisualBasic/Portable/Operations/VisualBasicOperationFactory.vb
+++ b/src/Compilers/VisualBasic/Portable/Operations/VisualBasicOperationFactory.vb
@@ -286,30 +286,30 @@ Namespace Microsoft.CodeAnalysis.Semantics
        End Function

        Private Function CreateBoundMeReferenceOperation(boundMeReference As BoundMeReference) As IInstanceReferenceExpression
-            Dim instanceReferenceKind As InstanceReferenceKind = If(boundMeReference.WasCompilerGenerated, InstanceReferenceKind.Implicit, InstanceReferenceKind.Explicit)
+            Dim isBaseReference = False
            Dim syntax As SyntaxNode = boundMeReference.Syntax
            Dim type As ITypeSymbol = boundMeReference.Type
            Dim constantValue As [Optional](Of Object) = ConvertToOptional(boundMeReference.ConstantValueOpt)
            Dim isImplicit As Boolean = boundMeReference.WasCompilerGenerated
-            Return New InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit)
+            Return New InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit)
        End Function

        Private Function CreateBoundMyBaseReferenceOperation(boundMyBaseReference As BoundMyBaseReference) As IInstanceReferenceExpression
-            Dim instanceReferenceKind As InstanceReferenceKind = InstanceReferenceKind.BaseClass
+            Dim isBaseReference = True
            Dim syntax As SyntaxNode = boundMyBaseReference.Syntax
            Dim type As ITypeSymbol = boundMyBaseReference.Type
            Dim constantValue As [Optional](Of Object) = ConvertToOptional(boundMyBaseReference.ConstantValueOpt)
            Dim isImplicit As Boolean = boundMyBaseReference.WasCompilerGenerated
-            Return New InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit)
+            Return New InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit)
        End Function

        Private Function CreateBoundMyClassReferenceOperation(boundMyClassReference As BoundMyClassReference) As IInstanceReferenceExpression
-            Dim instanceReferenceKind As InstanceReferenceKind = InstanceReferenceKind.ThisClass
+            Dim isBaseReference = True
            Dim syntax As SyntaxNode = boundMyClassReference.Syntax
            Dim type As ITypeSymbol = boundMyClassReference.Type
            Dim constantValue As [Optional](Of Object) = ConvertToOptional(boundMyClassReference.ConstantValueOpt)
            Dim isImplicit As Boolean = boundMyClassReference.WasCompilerGenerated
-            Return New InstanceReferenceExpression(instanceReferenceKind, _semanticModel, syntax, type, constantValue, isImplicit)
+            Return New InstanceReferenceExpression(isBaseReference, _semanticModel, syntax, type, constantValue, isImplicit)
        End Function

        Private Function CreateBoundLiteralOperation(boundLiteral As BoundLiteral) As ILiteralExpression

--- a/src/Compilers/VisualBasic/Test/Semantic/Binding/BindingObjectInitializerTests.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/Binding/BindingObjectInitializerTests.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports System.Linq.Enumerable
 Imports System.Xml.Linq
@@ -1176,7 +1176,7 @@ IObjectCreationExpression (Constructor: Sub C1..ctor()) (OperationKind.ObjectCre
            Left: IFieldReferenceExpression: C1.Field As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'Field')
                Instance Receiver: IOperation:  (OperationKind.None) (Syntax: 'New C1() Wi ... ivateField}')
            Right: IFieldReferenceExpression: C2.PrivateField As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'PrivateField')
-                Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C2) (Syntax: 'PrivateField')
+                Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C2) (Syntax: 'PrivateField')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -23,7 +23,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2(a As System.Int32, b As System.Double)) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, 0.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -55,7 +55,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -87,7 +87,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(a:=1, b:=1.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -119,7 +119,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=1.0, a:=0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '0')
        ILiteralExpression (Text: 0) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
@@ -151,7 +151,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=1.0, c:=2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(3):
      IArgument (ArgumentKind.DefaultValue, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
@@ -187,7 +187,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(, b:=1.0, c:=2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(3):
      IArgument (ArgumentKind.DefaultValue, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
@@ -223,7 +223,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(3):
      IArgument (ArgumentKind.DefaultValue, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
@@ -259,7 +259,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, c:=2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(3):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -295,7 +295,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -325,7 +325,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(x)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
        ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'x')
@@ -355,7 +355,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0], [ByRef b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=y, a:=x)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
        ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'x')
@@ -388,7 +388,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2()')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(1):
      IArgument (ArgumentKind.DefaultValue, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
@@ -416,7 +416,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: '1.0')
        IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: System.Int32, Constant: 1) (Syntax: '1.0')
@@ -447,7 +447,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(x)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
        ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Double) (Syntax: 'x')
@@ -484,7 +484,7 @@ End Module]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub P.E1([b As System.Int32 = 0], [c As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'E1(1, 2)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'E1')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'E1')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: b) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -521,7 +521,7 @@ End Module]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub P.E1([b As System.Int32 = 0], [c As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'E1(c:=1, b:=2)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'E1')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'E1')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: b) (OperationKind.Argument) (Syntax: '2')
        ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
@@ -557,7 +557,7 @@ End Class

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray y As System.Int32())) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, a)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -590,7 +590,7 @@ End Class

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray y As System.Int32())) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, 2, 3)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
@@ -631,7 +631,7 @@ End Class

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray y As System.Int32())) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
  Arguments(2):
      IArgument (ArgumentKind.Explicit, Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IEventAssignmentExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IEventAssignmentExpression.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.Test.Utilities
 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
@@ -31,10 +31,10 @@ End Class]]>.Value
 IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'AddHandler  ... AddressOf M')
  Expression: IEventAssignmentExpression (EventAdd)) (OperationKind.EventAssignmentExpression, Type: null) (Syntax: 'AddHandler  ... AddressOf M')
      Event Reference: IEventReferenceExpression: Event TestClass.TestEvent As System.Action (OperationKind.EventReferenceExpression, Type: System.Action) (Syntax: 'TestEvent')
-          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'TestEvent')
+          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'TestEvent')
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -64,10 +64,10 @@ End Class]]>.Value
 IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'RemoveHandl ... AddressOf M')
  Expression: IEventAssignmentExpression (EventRemove)) (OperationKind.EventAssignmentExpression, Type: null) (Syntax: 'RemoveHandl ... AddressOf M')
      Event Reference: IEventReferenceExpression: Event TestClass.TestEvent As System.Action (OperationKind.EventReferenceExpression, Type: System.Action) (Syntax: 'TestEvent')
-          Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'TestEvent')
+          Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'TestEvent')
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -100,7 +100,7 @@ IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'AddHandler  .
          Instance Receiver: null
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -133,7 +133,7 @@ IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'RemoveHandl .
          Instance Receiver: null
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -201,7 +201,7 @@ IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'AddHandler  .
          Instance Receiver: null
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = <![CDATA[
@@ -237,7 +237,7 @@ IExpressionStatement (OperationKind.ExpressionStatement, IsInvalid) (Syntax: 'Ad
          Instance Receiver: IOperation:  (OperationKind.None, IsInvalid) (Syntax: 'TestClass')
      Handler: IOperation:  (OperationKind.None) (Syntax: 'AddressOf M')
          Children(1):
-              IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
+              IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: TestClass) (Syntax: 'M')
 ]]>.Value

            Dim expectedDiagnostics = <![CDATA[

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IForLoopStatement.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IForLoopStatement.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.Semantics
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -647,7 +647,7 @@ IForLoopStatement (LoopKind.For) (OperationKind.LoopStatement) (Syntax: 'For i A
            Right: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: System.Int32) (Syntax: 'P1(30 + i)')
                Conversion: CommonConversion (Exists: False, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: False) (MethodSymbol: null)
                Operand: IPropertyReferenceExpression: Property MyClass1.P1(x As System.Int64) As System.Byte (OperationKind.PropertyReferenceExpression, Type: System.Byte) (Syntax: 'P1(30 + i)')
-                    Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: MyClass1) (Syntax: 'P1')
+                    Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: MyClass1) (Syntax: 'P1')
                    Arguments(1):
                        IArgument (ArgumentKind.Explicit, Matching Parameter: x) (OperationKind.Argument) (Syntax: '30 + i')
                          IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: System.Int64) (Syntax: '30 + i')

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IInterpolatedStringExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IInterpolatedStringExpression.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -168,14 +168,14 @@ IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type:
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: "String ") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{x,20}')
        Expression: IFieldReferenceExpression: [Class].x As System.String (OperationKind.FieldReferenceExpression, Type: System.String) (Syntax: 'x')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'x')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'x')
        Alignment: ILiteralExpression (Text: 20) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 20) (Syntax: '20')
        FormatString: null
      IInterpolatedStringText (OperationKind.InterpolatedStringText) (Syntax: ' and ')
        Text: ILiteralExpression (Text:  and ) (OperationKind.LiteralExpression, Type: System.String, Constant: " and ") (Syntax: ' and ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{y:D3}')
        Expression: IFieldReferenceExpression: [Class].y As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'y')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'y')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'y')
        Alignment: null
        FormatString: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: "D3") (Syntax: ':D3')
      IInterpolatedStringText (OperationKind.InterpolatedStringText) (Syntax: ' and constant ')
@@ -212,7 +212,7 @@ IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type:
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: "String ") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{x,20:D3}')
        Expression: IFieldReferenceExpression: [Class].x As System.String (OperationKind.FieldReferenceExpression, Type: System.String) (Syntax: 'x')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'x')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'x')
        Alignment: ILiteralExpression (Text: 20) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 20) (Syntax: '20')
        FormatString: ILiteralExpression (OperationKind.LiteralExpression, Type: System.String, Constant: "D3") (Syntax: ':D3')
 ]]>.Value
@@ -253,7 +253,7 @@ IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type:
        Text: ILiteralExpression (Text:  and ) (OperationKind.LiteralExpression, Type: System.String, Constant: " and ") (Syntax: ' and ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{M2(y)}')
        Expression: IInvocationExpression ( Function [Class].M2(z As System.Int32) As System.String) (OperationKind.InvocationExpression, Type: System.String) (Syntax: 'M2(y)')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'M2')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'M2')
            Arguments(1):
                IArgument (ArgumentKind.Explicit, Matching Parameter: z) (OperationKind.Argument) (Syntax: 'y')
                  ILocalReferenceExpression: y (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'y')
@@ -299,7 +299,7 @@ IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type:
        Text: ILiteralExpression (Text: String ) (OperationKind.LiteralExpression, Type: System.String, Constant: "String ") (Syntax: 'String ')
      IInterpolation (OperationKind.Interpolation) (Syntax: '{M2($"{y}")}')
        Expression: IInvocationExpression ( Function [Class].M2(z As System.String) As System.Int32) (OperationKind.InvocationExpression, Type: System.Int32) (Syntax: 'M2($"{y}")')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'M2')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'M2')
            Arguments(1):
                IArgument (ArgumentKind.Explicit, Matching Parameter: z) (OperationKind.Argument) (Syntax: '$"{y}"')
                  IInterpolatedStringExpression (OperationKind.InterpolatedStringExpression, Type: System.String) (Syntax: '$"{y}"')

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_ILockStatement.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_ILockStatement.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.Test.Utilities
 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
@@ -25,7 +25,7 @@ End Class]]>.Value
            Dim expectedOperationTree = <![CDATA[
 ILockStatement (OperationKind.LockStatement) (Syntax: 'SyncLock o' ... nd SyncLock')
  Expression: IFieldReferenceExpression: C1.o As System.Object (OperationKind.FieldReferenceExpression, Type: System.Object) (Syntax: 'o')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'o')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'o')
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: 'SyncLock o' ... nd SyncLock')
 ]]>.Value

@@ -252,7 +252,7 @@ End Class]]>.Value
            Dim expectedOperationTree = <![CDATA[
 ILockStatement (OperationKind.LockStatement) (Syntax: 'SyncLock M2 ... nd SyncLock')
  Expression: IInvocationExpression ( Function C1.M2() As System.Object) (OperationKind.InvocationExpression, Type: System.Object) (Syntax: 'M2()')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1) (Syntax: 'M2')
      Arguments(0)
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement) (Syntax: 'SyncLock M2 ... nd SyncLock')
 ]]>.Value
@@ -283,7 +283,7 @@ ILockStatement (OperationKind.LockStatement, IsInvalid) (Syntax: 'SyncLock M2 ..
  Expression: IInvalidExpression (OperationKind.InvalidExpression, Type: ?, IsInvalid) (Syntax: 'M2()')
      Children(1):
          IInvocationExpression ( Sub C1.M2()) (OperationKind.InvocationExpression, Type: System.Void, IsInvalid) (Syntax: 'M2()')
-            Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
+            Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C1, IsInvalid) (Syntax: 'M2')
            Arguments(0)
  Body: IBlockStatement (0 statements) (OperationKind.BlockStatement, IsInvalid) (Syntax: 'SyncLock M2 ... nd SyncLock')
 ]]>.Value

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IObjectCreationExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IObjectCreationExpression.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -176,7 +176,7 @@ IObjectCreationExpression (Constructor: Sub System.Collections.Generic.List(Of S
          ICollectionElementInitializerExpression (AddMethod: Sub System.Collections.Generic.List(Of System.Int32).Add(item As System.Int32)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'field')
            Arguments(1):
                IFieldReferenceExpression: C.field As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
+                  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -227,7 +227,7 @@ IObjectCreationExpression (Constructor: Sub System.Collections.Generic.List(Of S
                          ICollectionElementInitializerExpression (AddMethod: Sub System.Collections.Generic.List(Of System.Int32).Add(item As System.Int32)) (IsDynamic: False) (OperationKind.CollectionElementInitializerExpression, Type: System.Void) (Syntax: 'field')
                            Arguments(1):
                                IFieldReferenceExpression: C.field As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                                  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
+                                  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'field')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty
@@ -302,7 +302,7 @@ IObjectCreationExpression (Constructor: Sub [Class]..ctor()) (OperationKind.Obje
                          Left: IPropertyReferenceExpression: Property [Class].X As System.Int32 (OperationKind.PropertyReferenceExpression, Type: System.Int32) (Syntax: 'X')
                              Instance Receiver: IOperation:  (OperationKind.None) (Syntax: 'New [Class] ... .X = field}')
                          Right: IFieldReferenceExpression: [Class].field As System.Int32 (OperationKind.FieldReferenceExpression, Type: System.Int32) (Syntax: 'field')
-                              Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'field')
+                              Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: [Class]) (Syntax: 'field')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IParameterReferenceExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IParameterReferenceExpression.vb
-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

 Imports Microsoft.CodeAnalysis.Semantics
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -413,7 +413,7 @@ IConversionExpression (Explicit, TryCast: False, Unchecked) (OperationKind.Conve
  Conversion: CommonConversion (Exists: False, IsIdentity: False, IsNumeric: False, IsReference: False, IsUserDefined: False) (MethodSymbol: null)
  Operand: IOperation:  (OperationKind.None) (Syntax: 'AddressOf Me.M')
      Children(1):
-          IInstanceReferenceExpression (InstanceReferenceKind.Explicit) (OperationKind.InstanceReferenceExpression, Type: Class1) (Syntax: 'Me')
+          IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Class1) (Syntax: 'Me')
 ]]>.Value

            Dim expectedDiagnostics = String.Empty

--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IUnaryOperatorExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IUnaryOperatorExpression.vb
--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IWhileUntilLoopStatement.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IWhileUntilLoopStatement.vb
@@ -931,7 +931,7 @@ End Class
            Dim expectedOperationTree = <![CDATA[
 IWhileUntilLoopStatement (IsTopTest: True, IsWhile: True) (LoopKind.WhileUntil) (OperationKind.LoopStatement) (Syntax: 'Do While G( ... Loop')
  Condition: IInvocationExpression ( Function C.G() As System.Boolean) (OperationKind.InvocationExpression, Type: System.Boolean) (Syntax: 'G()')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'G')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'G')
      Arguments(0)
  Body: IBlockStatement (1 statements) (OperationKind.BlockStatement) (Syntax: 'Do While G( ... Loop')
      IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'Console.WriteLine(1)')
@@ -941,7 +941,8 @@ IWhileUntilLoopStatement (IsTopTest: True, IsWhile: True) (LoopKind.WhileUntil)
                IArgument (ArgumentKind.Explicit, Matching Parameter: value) (OperationKind.Argument) (Syntax: '1')
                  ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
                  InConversion: null
-                  OutConversion: null]]>.Value
+                  OutConversion: null
+]]>.Value

            VerifyOperationTreeForTest(Of DoLoopBlockSyntax)(source, expectedOperationTree)
        End Sub
@@ -968,7 +969,7 @@ End Class
            Dim expectedOperationTree = <![CDATA[
 IWhileUntilLoopStatement (IsTopTest: False, IsWhile: True) (LoopKind.WhileUntil) (OperationKind.LoopStatement) (Syntax: 'Do'BIND:"Do ... p While G()')
  Condition: IInvocationExpression ( Function C.G() As System.Boolean) (OperationKind.InvocationExpression, Type: System.Boolean) (Syntax: 'G()')
-      Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'G')
+      Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: C) (Syntax: 'G')
      Arguments(0)
  Body: IBlockStatement (1 statements) (OperationKind.BlockStatement) (Syntax: 'Do'BIND:"Do ... p While G()')
      IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'Console.WriteLine(1)')
@@ -980,6 +981,7 @@ IWhileUntilLoopStatement (IsTopTest: False, IsWhile: True) (LoopKind.WhileUntil)
                  InConversion: null
                  OutConversion: null
 ]]>.Value
+
            VerifyOperationTreeForTest(Of DoLoopBlockSyntax)(source, expectedOperationTree)
        End Sub


--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_InvalidExpression.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_InvalidExpression.vb
@@ -54,7 +54,7 @@ End Class]]>.Value

            Dim expectedOperationTree = <![CDATA[
 IInvocationExpression ( Sub Program.F(x As System.Int32)) (OperationKind.InvocationExpression, Type: System.Void, IsInvalid) (Syntax: 'F(String.Empty)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program, IsInvalid) (Syntax: 'F')
+  Instance Receiver: IInstanceReferenceExpression (IsBaseReference: False) (OperationKind.InstanceReferenceExpression, Type: Program, IsInvalid) (Syntax: 'F')
  Arguments(1):
      IArgument (ArgumentKind.Explicit, Matching Parameter: x) (OperationKind.Argument) (Syntax: 'String.Empty')
        IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: System.Int32) (Syntax: 'String.Empty')

--- a/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs
+++ b/src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs
@@ -686,8 +686,7 @@ public override void VisitSyntheticLocalReferenceExpression(ISyntheticLocalRefer
        public override void VisitInstanceReferenceExpression(IInstanceReferenceExpression operation)
        {
            LogString(nameof(IInstanceReferenceExpression));
-            var kindStr = $"{nameof(InstanceReferenceKind)}.{operation.InstanceReferenceKind}";
-            LogString($" ({kindStr})");
+            LogString($" (IsBaseReference: {operation.IsBaseReference})");
            LogCommonPropertiesAndNewLine(operation);
        }


--- a/src/Test/Utilities/Portable/Compilation/TestOperationWalker.cs
+++ b/src/Test/Utilities/Portable/Compilation/TestOperationWalker.cs
@@ -261,7 +261,7 @@ public override void VisitSyntheticLocalReferenceExpression(ISyntheticLocalRefer

        public override void VisitInstanceReferenceExpression(IInstanceReferenceExpression operation)
        {
-            var instanceReferenceKind = operation.InstanceReferenceKind;
+            var isBaseReference = operation.IsBaseReference;

            base.VisitInstanceReferenceExpression(operation);
        }

--- a/src/Test/Utilities/Portable/Diagnostics/OperationTestAnalyzer.cs
+++ b/src/Test/Utilities/Portable/Diagnostics/OperationTestAnalyzer.cs
@@ -971,7 +971,13 @@ public sealed override void Initialize(AnalysisContext context)
                 (operationContext) =>
                 {
                     IInstanceReferenceExpression instanceReference = (IInstanceReferenceExpression)operationContext.Operation;
-                     operationContext.ReportDiagnostic(Diagnostic.Create(instanceReference.InstanceReferenceKind == InstanceReferenceKind.Implicit ? ImplicitInstanceDescriptor : ExplicitInstanceDescriptor, instanceReference.Syntax.GetLocation()));
+                     operationContext.ReportDiagnostic(Diagnostic.Create(instanceReference.Syntax.IsKind(CSharp.SyntaxKind.ThisExpression) ||
+                                                                            instanceReference.Syntax.IsKind(VisualBasic.SyntaxKind.MeExpression) ||
+                                                                            instanceReference.Syntax.IsKind(VisualBasic.SyntaxKind.MyClassExpression) ||
+                                                                            instanceReference.Syntax.IsKind(CSharp.SyntaxKind.BaseExpression) ||
+                                                                            instanceReference.Syntax.IsKind(VisualBasic.SyntaxKind.MyBaseExpression)
+                                                                            ? ExplicitInstanceDescriptor : ImplicitInstanceDescriptor,
+                                                                         instanceReference.Syntax.GetLocation()));
                 },
                 OperationKind.InstanceReferenceExpression);
        }