[hot reload][mono] Implement support for adding static and instance fields to generic classes (#87285)

Fixes #86111

* new test adding a generic field

* workaround roslyn issue to generate generic static field test

   dotnet/roslyn#68293 we get an error if we add a generic field and try to use it during the same edit. workaround is to do two separate edits

* implement hot reload for static fields in generics

   ldsflda seems to be working

* Add a generic instance add instance field test

* add reflection testing to the generic instance added field test

* fixup valuetype loads

* add non-generic valuetype ldflda test

* Mark failing tests for CoreCLR

* light up GenericAddFieldToExistingType capability

* use interp_emit_ldobj for metadata-update; add barrier if volatile

Author: lambdageek

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.AddInstanceField/AddInstanceField.cs

@@ -47,5 +47,7 @@ public double FireEvents() {
 
             return Accumulator;
         }
+
+        public DateTime GetDateTime() => default(DateTime);
     }
 }

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.AddInstanceField/AddInstanceField_v1.cs

@@ -85,6 +85,11 @@ public double FireEvents() {
             return Accumulator;
         }
 
+        public DateTime GetDateTime() => default(DateTime);
+
         public double AddedFirstProp {get => 0.0; set { Console.WriteLine (value); } }
+
+        public DateTime AddedDateTime;
+
     }
 }

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.AddInstanceField/AddInstanceField_v2.cs

@@ -85,7 +85,12 @@ public double FireEvents() {
             return Accumulator;
         }
 
+        public DateTime GetDateTime() => AddedDateTime;
+
         public double AddedFirstProp {get => 0.0; set { Console.WriteLine (value+value); } }
         public short AddedSecondProp {get; set; }
+
+        public DateTime AddedDateTime;
+
     }
 }

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField/GenericAddInstanceField.cs

@@ -0,0 +1,18 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using System;
+
+
+namespace System.Reflection.Metadata.ApplyUpdate.Test
+{
+    public class GenericAddInstanceField<T>
+    {
+        public GenericAddInstanceField (T p) {
+        }
+
+        public T GetIt()
+        {
+            return default(T);
+        }
+    }
+}

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField/GenericAddInstanceField_v1.cs

@@ -0,0 +1,20 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using System;
+
+
+namespace System.Reflection.Metadata.ApplyUpdate.Test
+{
+    public class GenericAddInstanceField<T>
+    {
+        public GenericAddInstanceField (T p) {
+        }
+
+        T myAddedField;
+
+        public T GetIt()
+        {
+            return default(T);
+        }
+    }
+}

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField/GenericAddInstanceField_v2.cs

@@ -0,0 +1,21 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using System;
+
+
+namespace System.Reflection.Metadata.ApplyUpdate.Test
+{
+    public class GenericAddInstanceField<T>
+    {
+        public GenericAddInstanceField (T p) {
+            myAddedField = p;
+        }
+
+        T myAddedField;
+
+        public T GetIt()
+        {
+            return myAddedField;
+        }
+    }
+}

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField.csproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <RootNamespace>System.Runtime.Loader.Tests</RootNamespace>
+    <TargetFramework>$(NetCoreAppCurrent)</TargetFramework>
+    <TestRuntime>true</TestRuntime>
+    <DeltaScript>deltascript.json</DeltaScript>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="GenericAddInstanceField.cs" />
+  </ItemGroup>
+</Project>

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddInstanceField/deltascript.json

@@ -0,0 +1,7 @@
+{
+    "changes": [
+        {"document": "GenericAddInstanceField.cs", "update": "GenericAddInstanceField_v1.cs"},
+        {"document": "GenericAddInstanceField.cs", "update": "GenericAddInstanceField_v2.cs"},
+    ]
+}
+

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddStaticField/GenericAddStaticField.cs

@@ -0,0 +1,22 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using System;
+
+
+namespace System.Reflection.Metadata.ApplyUpdate.Test
+{
+    public class GenericAddStaticField<T>
+    {
+        public GenericAddStaticField () {
+        }
+
+        public T GetField () => s_field;
+
+        private static T s_field;
+
+        public void TestMethod () {
+            s_field = (T)(object)"abcd";
+        }
+
+    }
+}

src/libraries/System.Runtime.Loader/tests/ApplyUpdate/System.Reflection.Metadata.ApplyUpdate.Test.GenericAddStaticField/GenericAddStaticField_v1.cs

@@ -0,0 +1,25 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using System;
+
+
+namespace System.Reflection.Metadata.ApplyUpdate.Test
+{
+    public class GenericAddStaticField<T>
+    {
+        public GenericAddStaticField () {
+        }
+
+        public T GetField () => s_field;
+
+        private static T s_field;
+
+        public static T s_field2;
+
+        public void TestMethod () {
+            s_field = (T)(object)"spqr";
+            //s_field2 = (T)(object)"4567";
+        }
+
+    }
+}