Fix function pointer representation

src/ExpressionEvaluator/CSharp/Test/ResultProvider/FunctionPointerTests.cs

@@ -3,6 +3,8 @@
 using Microsoft.CodeAnalysis.ExpressionEvaluator;
 using Microsoft.VisualStudio.Debugger.Clr;
 using Microsoft.VisualStudio.Debugger.Evaluation;
+using Microsoft.VisualStudio.Debugger.Evaluation.ClrCompilation;
+using Microsoft.VisualStudio.Debugger.Metadata;
 using System;
 using System.Diagnostics;
 using Xunit;
@@ -12,40 +14,71 @@ namespace Microsoft.CodeAnalysis.CSharp.UnitTests
 {
     public class FunctionPointerTests : CSharpResultProviderTestBase
     {
-        [Fact(Skip = "Tests are failing in Jenkins queues")]
+        [Fact]
         public void Root()
         {
-            const int ptr = 0x1234;
-            var value = CreateDkmClrValue(ptr, type: new DkmClrType(FunctionPointerType.Instance));
-            var evalResult = FormatResult("pfn", value);
-            Verify(evalResult,
-                EvalResult("pfn", PointerToString(new IntPtr(ptr)), "System.Object*", "pfn", DkmEvaluationResultFlags.None, DkmEvaluationResultCategory.Other));
+            var source =
+@"unsafe class C
+{
+    internal C(long p)
+    {
+        this.pfn = (int*)p;
+    }
+    int* pfn;
+}";
+            var assembly = GetUnsafeAssembly(source);
+            unsafe
+            {
+                int i = 0x1234;
+                long ptr = (long)&i;
+                var type = assembly.GetType("C");
+                var value = GetFunctionPointerField(CreateDkmClrValue(type.Instantiate(ptr)), "pfn");
+                var evalResult = FormatResult("pfn", value);
+                Verify(evalResult,
+                    EvalResult("pfn", PointerToString(new IntPtr(ptr)), "System.Object*", "pfn", DkmEvaluationResultFlags.None, DkmEvaluationResultCategory.Other));
+            }
         }
 
-        [Fact(Skip = "Tests are failing in Jenkins queues")]
+        [Fact]
         public void Member()
         {
             var source =
-@"class C
+@"unsafe class C
 {
-    object pfn;
+    internal C(long p)
+    {
+        this.pfn = (int*)p;
+    }
+    int* pfn;
 }";
-            const int ptr = 0x0;
-            GetMemberValueDelegate getMemberValue = (v, m) => (m == "pfn") ? CreateDkmClrValue(ptr, type: new DkmClrType(FunctionPointerType.Instance)) : null;
-            var runtime = new DkmClrRuntimeInstance(ReflectionUtilities.GetMscorlibAndSystemCore(GetAssembly(source)), getMemberValue: getMemberValue);
-            using (runtime.Load())
+            var assembly = GetUnsafeAssembly(source);
+            unsafe
             {
-                var type = runtime.GetType("C");
-                var value = CreateDkmClrValue(type.Instantiate(), type: type);
-                var evalResult = FormatResult("o", value);
-                Verify(evalResult,
-                    EvalResult("o", "{C}", "C", "o", DkmEvaluationResultFlags.Expandable, DkmEvaluationResultCategory.Other));
-                var children = GetChildren(evalResult);
-                Verify(children,
-                    EvalResult("pfn", PointerToString(new IntPtr(ptr)), "object {System.Object*}", "o.pfn", DkmEvaluationResultFlags.None, DkmEvaluationResultCategory.Other));
+                const long ptr = 0x0;
+                GetMemberValueDelegate getMemberValue = (v, m) => (m == "pfn") ? GetFunctionPointerField(v, m) : null;
+                var runtime = new DkmClrRuntimeInstance(ReflectionUtilities.GetMscorlibAndSystemCore(assembly), getMemberValue: getMemberValue);
+                using (runtime.Load())
+                {
+                    var type = runtime.GetType("C");
+                    var value = CreateDkmClrValue(type.Instantiate(ptr), type);
+                    var evalResult = FormatResult("o", value);
+                    Verify(evalResult,
+                        EvalResult("o", "{C}", "C", "o", DkmEvaluationResultFlags.Expandable, DkmEvaluationResultCategory.Other));
+                    var children = GetChildren(evalResult);
+                    Verify(children,
+                        EvalResult("pfn", PointerToString(new IntPtr(ptr)), "int*", "o.pfn", DkmEvaluationResultFlags.None, DkmEvaluationResultCategory.Other));
+                }
             }
         }
 
+        private DkmClrValue GetFunctionPointerField(DkmClrValue value, string fieldName)
+        {
+            var valueType = value.Type.GetLmrType();
+            var fieldInfo = valueType.GetField(fieldName, BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
+            var fieldValue = fieldInfo.GetValue(value.RawValue);
+            return CreateDkmClrValue(DkmClrValue.UnboxPointer(fieldValue), new DkmClrType(FunctionPointerType.Instance));
+        }
+
         // Function pointer type has IsPointer == true and GetElementType() == null.
         private sealed class FunctionPointerType : TypeImpl
         {

src/ExpressionEvaluator/Core/Test/ResultProvider/Debugger/Engine/DkmClrValue.cs

@@ -501,17 +501,7 @@ public DkmClrValue GetMemberValue(string MemberName, int MemberType, string Pare
             Type type;
             if (value is System.Reflection.Pointer)
             {
-                unsafe
-                {
-                    if (Environment.Is64BitProcess)
-                    {
-                        value = (long)System.Reflection.Pointer.Unbox(value);
-                    }
-                    else
-                    {
-                        value = (int)System.Reflection.Pointer.Unbox(value);
-                    }
-                }
+                value = UnboxPointer(value);
                 type = declaredType;
             }
             else if (value == null || declaredType.IsNullable())
@@ -535,6 +525,21 @@ public DkmClrValue GetMemberValue(string MemberName, int MemberType, string Pare
                 access: access);
         }
 
+        internal static unsafe object UnboxPointer(object value)
+        {
+            unsafe
+            {
+                if (Environment.Is64BitProcess)
+                {
+                    return (long)System.Reflection.Pointer.Unbox(value);
+                }
+                else
+                {
+                    return (int)System.Reflection.Pointer.Unbox(value);
+                }
+            }
+        }
+
         public DkmClrValue GetArrayElement(int[] indices, DkmInspectionContext inspectionContext)
         {
             if (inspectionContext == null)