For perf, remove Invoker pattern for fields (#74614)

src/coreclr/System.Private.CoreLib/src/System/Reflection/RtFieldInfo.cs

@@ -18,23 +18,12 @@ internal sealed unsafe class RtFieldInfo : RuntimeFieldInfo, IRuntimeFieldInfo
         // lazy caching
         private string? m_name;
         private RuntimeType? m_fieldType;
-        internal FieldAccessor? m_invoker;
-
+        private InvocationFlags m_invocationFlags;
         internal InvocationFlags InvocationFlags
         {
             [MethodImpl(MethodImplOptions.AggressiveInlining)]
-            get => (Invoker._invocationFlags & InvocationFlags.Initialized) != 0 ?
-                    Invoker._invocationFlags : InitializeInvocationFlags();
-        }
-
-        private FieldAccessor Invoker
-        {
-            [MethodImpl(MethodImplOptions.AggressiveInlining)]
-            get
-            {
-                m_invoker ??= new FieldAccessor(this);
-                return m_invoker;
-            }
+            get => (m_invocationFlags & InvocationFlags.Initialized) != 0 ?
+                    m_invocationFlags : InitializeInvocationFlags();
         }
 
         [MethodImpl(MethodImplOptions.NoInlining)]
@@ -67,7 +56,7 @@ private InvocationFlags InitializeInvocationFlags()
             }
 
             // must be last to avoid threading problems
-            return Invoker._invocationFlags = invocationFlags | InvocationFlags.Initialized;
+            return m_invocationFlags = invocationFlags | InvocationFlags.Initialized;
         }
         #endregion
 
@@ -113,63 +102,6 @@ internal override bool CacheEquals(object? o)
             return o is RtFieldInfo m && m.m_fieldHandle == m_fieldHandle;
         }
 
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        internal object? GetValueNonEmit(object? obj)
-        {
-            RuntimeType? declaringType = DeclaringType as RuntimeType;
-            RuntimeType fieldType = (RuntimeType)FieldType;
-            bool domainInitialized = false;
-
-            if (declaringType == null)
-            {
-                return RuntimeFieldHandle.GetValue(this, obj, fieldType, null, ref domainInitialized);
-            }
-            else
-            {
-                domainInitialized = declaringType.DomainInitialized;
-                object? retVal = RuntimeFieldHandle.GetValue(this, obj, fieldType, declaringType, ref domainInitialized);
-                declaringType.DomainInitialized = domainInitialized;
-                return retVal;
-            }
-        }
-
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        internal void SetValueNonEmit(object? obj, object? value)
-        {
-            RuntimeType? declaringType = DeclaringType as RuntimeType;
-            RuntimeType fieldType = (RuntimeType)FieldType;
-            bool domainInitialized = false;
-
-            if (declaringType == null)
-            {
-                RuntimeFieldHandle.SetValue(
-                    this,
-                    obj,
-                    value,
-                    fieldType,
-                    Attributes,
-                    declaringType: null,
-                    ref domainInitialized);
-            }
-            else
-            {
-                domainInitialized = declaringType.DomainInitialized;
-
-                RuntimeFieldHandle.SetValue(
-                    this,
-                    obj,
-                    value,
-                    fieldType,
-                    Attributes,
-                    declaringType,
-                    ref domainInitialized);
-
-                declaringType.DomainInitialized = domainInitialized;
-            }
-        }
-
         #endregion
 
         #region MemberInfo Overrides
@@ -211,7 +143,20 @@ internal override RuntimeModule GetRuntimeModule()
 
             CheckConsistency(obj);
 
-            return Invoker.GetValue(obj);
+            RuntimeType fieldType = (RuntimeType)FieldType;
+
+            bool domainInitialized = false;
+            if (declaringType == null)
+            {
+                return RuntimeFieldHandle.GetValue(this, obj, fieldType, null, ref domainInitialized);
+            }
+            else
+            {
+                domainInitialized = declaringType.DomainInitialized;
+                object? retVal = RuntimeFieldHandle.GetValue(this, obj, fieldType, declaringType, ref domainInitialized);
+                declaringType.DomainInitialized = domainInitialized;
+                return retVal;
+            }
         }
 
         public override object GetRawConstantValue() { throw new InvalidOperationException(); }
@@ -258,7 +203,17 @@ public override void SetValue(object? obj, object? value, BindingFlags invokeAtt
                 fieldType.CheckValue(ref value, copyBack: ref _ref, binder, culture, invokeAttr);
             }
 
-            Invoker.SetValue(obj, value);
+            bool domainInitialized = false;
+            if (declaringType is null)
+            {
+                RuntimeFieldHandle.SetValue(this, obj, value, fieldType, m_fieldAttributes, null, ref domainInitialized);
+            }
+            else
+            {
+                domainInitialized = declaringType.DomainInitialized;
+                RuntimeFieldHandle.SetValue(this, obj, value, fieldType, m_fieldAttributes, declaringType, ref domainInitialized);
+                declaringType.DomainInitialized = domainInitialized;
+            }
         }
 
         [DebuggerStepThrough]

src/coreclr/System.Private.CoreLib/src/System/RuntimeHandles.cs

@@ -1185,7 +1185,6 @@ public RuntimeFieldInfoStub(RuntimeFieldHandleInternal fieldHandle, object keepa
         private object? m_d;
         private int m_b;
         private object? m_e;
-        private object? m_f;
         private RuntimeFieldHandleInternal m_fieldHandle;
 #pragma warning restore 414, 169
 

src/coreclr/vm/object.h

@@ -1153,7 +1153,6 @@ protected:
     INT32               m_empty2;
     OBJECTREF           m_empty3;
     OBJECTREF           m_empty4;
-    OBJECTREF           m_empty5;
     FieldDesc *         m_pFD;
 
 public:

src/libraries/System.Private.CoreLib/src/System.Private.CoreLib.Shared.projitems

@@ -617,7 +617,6 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\EventInfo.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\ExceptionHandlingClause.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\ExceptionHandlingClauseOptions.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\FieldAccessor.cs" Condition="'$(FeatureNativeAot)' != 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\FieldAttributes.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\FieldInfo.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Reflection\GenericParameterAttributes.cs" />

src/libraries/System.Private.CoreLib/src/System/Reflection/FieldAccessor.cs

-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-
-using System.Diagnostics;
-
-namespace System.Reflection
-{
-    internal sealed partial class FieldAccessor
-    {
-        private readonly RtFieldInfo _fieldInfo;
-        public InvocationFlags _invocationFlags;
-
-        public FieldAccessor(RtFieldInfo fieldInfo)
-        {
-            _fieldInfo = fieldInfo;
-        }
-
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        public object? GetValue(object? obj)
-        {
-            // Todo: add strategy for calling IL Emit-based version
-            return _fieldInfo.GetValueNonEmit(obj);
-        }
-
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        public void SetValue(object? obj, object? value)
-        {
-            // Todo: add strategy for calling IL Emit-based version
-            _fieldInfo.SetValueNonEmit(obj, value);
-        }
-    }
-}

src/mono/System.Private.CoreLib/src/System/Reflection/RuntimeFieldInfo.cs

@@ -38,8 +38,6 @@ internal abstract class RtFieldInfo : FieldInfo
         internal abstract object UnsafeGetValue(object obj);
         internal abstract void UnsafeSetValue(object obj, object value, BindingFlags invokeAttr, Binder binder, CultureInfo culture);
         internal abstract void CheckConsistency(object target);
-        internal abstract object? GetValueNonEmit(object? obj);
-        internal abstract void SetValueNonEmit(object? obj, object? value);
     }
 
     [StructLayout(LayoutKind.Sequential)]
@@ -51,19 +49,8 @@ internal sealed class RuntimeFieldInfo : RtFieldInfo
         private string? name;
         private Type? type;
         private FieldAttributes attrs;
-        private FieldAccessor? invoker;
 #pragma warning restore 649
 
-        private FieldAccessor Invoker
-        {
-            [MethodImpl(MethodImplOptions.AggressiveInlining)]
-            get
-            {
-                invoker ??= new FieldAccessor(this);
-                return invoker;
-            }
-        }
-
         public override Module Module
         {
             get
@@ -128,13 +115,6 @@ public override void SetValueDirect(TypedReference obj, object value)
             }
         }
 
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        internal override void SetValueNonEmit(object? obj, object? value)
-        {
-            SetValueInternal(this, obj, value);
-        }
-
         [DebuggerStepThrough]
         [DebuggerHidden]
         public override object GetValueDirect(TypedReference obj)
@@ -149,13 +129,6 @@ public override object GetValueDirect(TypedReference obj)
             }
         }
 
-        [DebuggerStepThrough]
-        [DebuggerHidden]
-        internal override object? GetValueNonEmit(object? obj)
-        {
-            return GetValueInternal(obj);
-        }
-
         public override FieldAttributes Attributes
         {
             get
@@ -239,7 +212,7 @@ public override object[] GetCustomAttributes(Type attributeType, bool inherit)
             if (!IsLiteral)
                 CheckGeneric();
 
-            return Invoker.GetValue(obj);
+            return GetValueInternal(obj);
         }
 
         public override string ToString()
@@ -278,7 +251,7 @@ public override void SetValue(object? obj, object? val, BindingFlags invokeAttr,
                 }
             }
 
-            Invoker.SetValue(obj, val);
+            SetValueInternal(this, obj, val);
         }
 
         internal RuntimeFieldInfo Clone(string newName)