Cleanup System.Reflection.Emit code and delete dead code (#21086)

* Cleanup System.Reflection.Emit code

* Delete dead code from System.Reflection.Emit

16 files changed, 451 insertions, 1154 deletions

diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilder.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilder.cs
index 06ed8d13dd..14330ae7e5 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilder.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilder.cs
@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-//
 // For each dynamic assembly there will be two AssemblyBuilder objects: the "internal" 
 // AssemblyBuilder object and the "external" AssemblyBuilder object.
 //  1.  The "internal" object is the real assembly object that the VM creates and knows about. However, 
@@ -19,25 +18,19 @@
 //      "internal" object.
 //
 // "internal" and "external" ModuleBuilders are similar
-//
+
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Diagnostics.SymbolStore;
+using System.Globalization;
+using System.IO;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Security;
+using System.Threading;
 
 namespace System.Reflection.Emit
 {
-    using System;
-    using System.Collections.Generic;
-    using System.Diagnostics;
-    using System.Diagnostics.SymbolStore;
-    using CultureInfo = System.Globalization.CultureInfo;
-    using System.IO;
-    using System.Reflection;
-    using System.Resources;
-    using System.Runtime.CompilerServices;
-    using System.Runtime.InteropServices;
-    using System.Runtime.Serialization;
-    using System.Runtime.Versioning;
-    using System.Security;
-    using System.Threading;
-
     // When the user calls AppDomain.DefineDynamicAssembly the loader creates a new InternalAssemblyBuilder. 
     // This InternalAssemblyBuilder can be retrieved via a call to Assembly.GetAssemblies() by untrusted code.
     // In the past, when InternalAssemblyBuilder was AssemblyBuilder, the untrusted user could down cast the
@@ -58,23 +51,26 @@ namespace System.Reflection.Emit
     {
         private InternalAssemblyBuilder() { }
 
-        #region object overrides
         public override bool Equals(object obj)
         {
             if (obj == null)
+            {
                 return false;
+            }
 
             if (obj is InternalAssemblyBuilder)
-                return ((object)this == obj);
+            {
+                return (object)this == obj;
+            }
 
             return obj.Equals(this);
         }
-        // Need a dummy GetHashCode to pair with Equals
-        public override int GetHashCode() { return base.GetHashCode(); }
-        #endregion
+
+        public override int GetHashCode() => base.GetHashCode();
 
         // Assembly methods that are overridden by AssemblyBuilder should be overridden by InternalAssemblyBuilder too
         #region Methods inherited from Assembly
+
         public override string[] GetManifestResourceNames()
         {
             throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
@@ -107,18 +103,12 @@ namespace System.Reflection.Emit
 
         public override string Location
         {
-            get
-            {
-                throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
-            }
+            get => throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
         }
 
         public override string CodeBase
         {
-            get
-            {
-                throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
-            }
+            get => throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
         }
 
         public override Type[] GetExportedTypes()
@@ -126,76 +116,54 @@ namespace System.Reflection.Emit
             throw new NotSupportedException(SR.NotSupported_DynamicAssembly);
         }
 
-        public override string ImageRuntimeVersion
-        {
-            get
-            {
-                return RuntimeEnvironment.GetSystemVersion();
-            }
-        }
+        public override string ImageRuntimeVersion => RuntimeEnvironment.GetSystemVersion();
+
         #endregion
     }
     
     public sealed class AssemblyBuilder : Assembly
     {
-        #region FCALL
         [MethodImplAttribute(MethodImplOptions.InternalCall)]
         private static extern RuntimeModule GetInMemoryAssemblyModule(RuntimeAssembly assembly);
 
-        private Module nGetInMemoryAssemblyModule()
-        {
-            return AssemblyBuilder.GetInMemoryAssemblyModule(GetNativeHandle());
-        }
-
-        #endregion
-
         #region Internal Data Members
+
         // This is only valid in the "external" AssemblyBuilder
-        internal AssemblyBuilderData m_assemblyData;
-        private InternalAssemblyBuilder m_internalAssemblyBuilder;
-        private ModuleBuilder m_manifestModuleBuilder;
+        internal AssemblyBuilderData _assemblyData;
+        private readonly InternalAssemblyBuilder _internalAssemblyBuilder;
+        private ModuleBuilder _manifestModuleBuilder;
         // Set to true if the manifest module was returned by code:DefineDynamicModule to the user
-        private bool m_fManifestModuleUsedAsDefinedModule;
-        internal const string MANIFEST_MODULE_NAME = "RefEmit_InMemoryManifestModule";
+        private bool _isManifestModuleUsedAsDefinedModule;
+
+        private const string ManifestModuleName = "RefEmit_InMemoryManifestModule";
 
         internal ModuleBuilder GetModuleBuilder(InternalModuleBuilder module)
         {
             Debug.Assert(module != null);
-            Debug.Assert(this.InternalAssembly == module.Assembly);
+            Debug.Assert(InternalAssembly == module.Assembly);
 
             lock (SyncRoot)
             {
                 // in CoreCLR there is only one module in each dynamic assembly, the manifest module
-                if (m_manifestModuleBuilder.InternalModule == module)
-                    return m_manifestModuleBuilder;
+                if (_manifestModuleBuilder.InternalModule == module)
+                {
+                    return _manifestModuleBuilder;
+                }
 
                 throw new ArgumentException(null, nameof(module));
             }
         }
 
-        internal object SyncRoot
-        {
-            get
-            {
-                return InternalAssembly.SyncRoot;
-            }
-        }
+        internal object SyncRoot => InternalAssembly.SyncRoot;
 
-        internal InternalAssemblyBuilder InternalAssembly
-        {
-            get
-            {
-                return m_internalAssemblyBuilder;
-            }
-        }
+        internal InternalAssemblyBuilder InternalAssembly => _internalAssemblyBuilder;
+
+        internal RuntimeAssembly GetNativeHandle() => InternalAssembly.GetNativeHandle();
 
-        internal RuntimeAssembly GetNativeHandle()
-        {
-            return InternalAssembly.GetNativeHandle();
-        }
         #endregion
 
         #region Constructor
+
         internal AssemblyBuilder(AppDomain domain,
                                  AssemblyName name,
                                  AssemblyBuilderAccess access,
@@ -203,11 +171,10 @@ namespace System.Reflection.Emit
                                  IEnumerable<CustomAttributeBuilder> unsafeAssemblyAttributes)
         {
             if (name == null)
+            {
                 throw new ArgumentNullException(nameof(name));
-
-            if (access != AssemblyBuilderAccess.Run
-                && access != AssemblyBuilderAccess.RunAndCollect
-                )
+            }
+            if (access != AssemblyBuilderAccess.Run && access != AssemblyBuilderAccess.RunAndCollect)
             {
                 throw new ArgumentException(SR.Format(SR.Arg_EnumIllegalVal, (int)access), nameof(access));
             }
@@ -226,14 +193,12 @@ namespace System.Reflection.Emit
                 assemblyAttributes = new List<CustomAttributeBuilder>(unsafeAssemblyAttributes);
             }
 
-            m_internalAssemblyBuilder = (InternalAssemblyBuilder)nCreateDynamicAssembly(domain,
+            _internalAssemblyBuilder = (InternalAssemblyBuilder)nCreateDynamicAssembly(domain,
                                                                                         name,
                                                                                         ref stackMark,
                                                                                         access);
 
-            m_assemblyData = new AssemblyBuilderData(m_internalAssemblyBuilder,
-                                                     name.Name,
-                                                     access);
+            _assemblyData = new AssemblyBuilderData(_internalAssemblyBuilder, access);
 
             // Make sure that ManifestModule is properly initialized
             // We need to do this before setting any CustomAttribute
@@ -242,18 +207,20 @@ namespace System.Reflection.Emit
             if (assemblyAttributes != null)
             {
                 foreach (CustomAttributeBuilder assemblyAttribute in assemblyAttributes)
+                {
                     SetCustomAttribute(assemblyAttribute);
+                }
             }
         }
 
         private void InitManifestModule()
         {
-            InternalModuleBuilder modBuilder = (InternalModuleBuilder)nGetInMemoryAssemblyModule();
+            InternalModuleBuilder modBuilder = (InternalModuleBuilder)GetInMemoryAssemblyModule(GetNativeHandle());
 
             // Note that this ModuleBuilder cannot be used for RefEmit yet
             // because it hasn't been initialized.
             // However, it can be used to set the custom attribute on the Assembly
-            m_manifestModuleBuilder = new ModuleBuilder(this, modBuilder);
+            _manifestModuleBuilder = new ModuleBuilder(this, modBuilder);
 
             // We are only setting the name in the managed ModuleBuilderData here.
             // The name in the underlying metadata will be set when the
@@ -261,10 +228,11 @@ namespace System.Reflection.Emit
 
             // This name needs to stay in sync with that used in
             // Assembly::Init to call ReflectionModule::Create (in VM)
-            m_manifestModuleBuilder.Init(AssemblyBuilder.MANIFEST_MODULE_NAME, null, 0);
+            _manifestModuleBuilder.Init(ManifestModuleName);
 
-            m_fManifestModuleUsedAsDefinedModule = false;
+            _isManifestModuleUsedAsDefinedModule = false;
         }
+
         #endregion
 
         #region DefineDynamicAssembly
@@ -274,27 +242,21 @@ namespace System.Reflection.Emit
         /// to have a strong name and a hash will be computed when the assembly
         /// is saved.
         /// </summary>
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
-        public static AssemblyBuilder DefineDynamicAssembly(
-            AssemblyName name,
-            AssemblyBuilderAccess access)
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        public static AssemblyBuilder DefineDynamicAssembly(AssemblyName name, AssemblyBuilderAccess access)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            return InternalDefineDynamicAssembly(name, access,
-                                                 ref stackMark, null);
+            return InternalDefineDynamicAssembly(name, access, ref stackMark, null);
         }
         
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
         public static AssemblyBuilder DefineDynamicAssembly(
             AssemblyName name,
             AssemblyBuilderAccess access,
             IEnumerable<CustomAttributeBuilder> assemblyAttributes)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            return InternalDefineDynamicAssembly(name,
-                                                 access,
-                                                 ref stackMark,
-                                                 assemblyAttributes);
+            return InternalDefineDynamicAssembly(name, access, ref stackMark, assemblyAttributes);
         }
 
 
@@ -314,36 +276,32 @@ namespace System.Reflection.Emit
         {
             lock (typeof(AssemblyBuilderLock))
             {
-                // we can only create dynamic assemblies in the current domain
+                // We can only create dynamic assemblies in the current domain
                 return new AssemblyBuilder(AppDomain.CurrentDomain,
                                            name,
                                            access,
                                            ref stackMark,
                                            unsafeAssemblyAttributes);
-            } //lock(typeof(AssemblyBuilderLock))
+            }
         }
         #endregion
 
         #region DefineDynamicModule
+
         /// <summary>
         /// Defines a named dynamic module. It is an error to define multiple 
         /// modules within an Assembly with the same name. This dynamic module is
         /// a transient module.
         /// </summary>
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
-        public ModuleBuilder DefineDynamicModule(
-            string name)
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        public ModuleBuilder DefineDynamicModule(string name)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
             return DefineDynamicModuleInternal(name, false, ref stackMark);
         }
-        
-        /// <param name = "name" ></ param >
-        /// <param name = "emitSymbolInfo" >Specify if emit symbol info or not.</ param >
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
-        public ModuleBuilder DefineDynamicModule(
-            string name,
-            bool emitSymbolInfo)
+
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        public ModuleBuilder DefineDynamicModule(string name, bool emitSymbolInfo)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
             return DefineDynamicModuleInternal(name, emitSymbolInfo, ref stackMark);
@@ -366,89 +324,101 @@ namespace System.Reflection.Emit
             ref StackCrawlMark stackMark)
         {
             if (name == null)
+            {
                 throw new ArgumentNullException(nameof(name));
+            }
             if (name.Length == 0)
+            {
                 throw new ArgumentException(SR.Argument_EmptyName, nameof(name));
+            }
             if (name[0] == '\0')
+            {
                 throw new ArgumentException(SR.Argument_InvalidName, nameof(name));
+            }
 
-            Debug.Assert(m_assemblyData != null, "m_assemblyData is null in DefineDynamicModuleInternal");
-
-            ModuleBuilder dynModule;
-            ISymbolWriter writer = null;
-            IntPtr pInternalSymWriter = new IntPtr();
-
-            // create the dynamic module- only one ModuleBuilder per AssemblyBuilder can be created
-            if (m_fManifestModuleUsedAsDefinedModule == true)
+            // Create the dynamic module- only one ModuleBuilder per AssemblyBuilder can be created.
+            if (_isManifestModuleUsedAsDefinedModule)
+            {
                 throw new InvalidOperationException(SR.InvalidOperation_NoMultiModuleAssembly);
+            }
+
+            Debug.Assert(_assemblyData != null, "_assemblyData is null in DefineDynamicModuleInternal");
 
-            // Init(...) has already been called on m_manifestModuleBuilder in InitManifestModule()
-            dynModule = m_manifestModuleBuilder;
+            // Init(...) has already been called on _manifestModuleBuilder in InitManifestModule()
+            ModuleBuilder dynModule = _manifestModuleBuilder;
 
             // Create the symbol writer
+            ISymbolWriter writer = null;
             if (emitSymbolInfo)
             {
                 writer = SymWrapperCore.SymWriter.CreateSymWriter();
 
-                string fileName = "Unused"; // this symfile is never written to disk so filename does not matter.
-
-                // Pass the "real" module to the VM
-                pInternalSymWriter = ModuleBuilder.nCreateISymWriterForDynamicModule(dynModule.InternalModule, fileName);
-
-                // In Telesto, we took the SetUnderlyingWriter method private as it's a very rickety method.
-                // This might someday be a good move for the desktop CLR too.
+                // Pass the "real" module to the VM.
+                // This symfile is never written to disk so filename does not matter.
+                IntPtr pInternalSymWriter = ModuleBuilder.nCreateISymWriterForDynamicModule(dynModule.InternalModule, "Unused");
                 ((SymWrapperCore.SymWriter)writer).InternalSetUnderlyingWriter(pInternalSymWriter);
-            } // Creating the symbol writer
+            }
 
             dynModule.SetSymWriter(writer);
-            m_assemblyData.AddModule(dynModule);
+            _assemblyData._moduleBuilderList.Add(dynModule);
 
-            if (dynModule == m_manifestModuleBuilder)
-            {   // We are reusing manifest module as user-defined dynamic module
-                m_fManifestModuleUsedAsDefinedModule = true;
+            if (dynModule == _manifestModuleBuilder)
+            {
+                // We are reusing manifest module as user-defined dynamic module
+                _isManifestModuleUsedAsDefinedModule = true;
             }
 
             return dynModule;
-        } // DefineDynamicModuleInternalNoLock
+        }
 
         #endregion
 
         internal void CheckContext(params Type[][] typess)
         {
             if (typess == null)
+            {
                 return;
+            }
 
             foreach (Type[] types in typess)
+            {
                 if (types != null)
+                {
                     CheckContext(types);
+                }
+            }
         }
 
         internal void CheckContext(params Type[] types)
         {
             if (types == null)
+            {
                 return;
+            }
 
             foreach (Type type in types)
             {
                 if (type == null)
+                {
                     continue;
+                }
 
                 if (type.Module == null || type.Module.Assembly == null)
+                {
                     throw new ArgumentException(SR.Argument_TypeNotValid);
+                }
 
                 if (type.Module.Assembly == typeof(object).Module.Assembly)
+                {
                     continue;
+                }
             }
         }
 
-        #region object overrides
-        public override bool Equals(object obj)
-        {
-            return InternalAssembly.Equals(obj);
-        }
+        public override bool Equals(object obj) => InternalAssembly.Equals(obj);
+
         // Need a dummy GetHashCode to pair with Equals
-        public override int GetHashCode() { return InternalAssembly.GetHashCode(); }
-        #endregion
+        public override int GetHashCode() => InternalAssembly.GetHashCode();
 
         #region ICustomAttributeProvider Members
         public override object[] GetCustomAttributes(bool inherit)
@@ -470,9 +440,11 @@ namespace System.Reflection.Emit
         {
             return InternalAssembly.GetCustomAttributesData();
         }
+
         #endregion
 
         #region Assembly overrides
+
         /// <returns>The names of all the resources.</returns>
         public override string[] GetManifestResourceNames()
         {
@@ -504,109 +476,46 @@ namespace System.Reflection.Emit
             return InternalAssembly.GetManifestResourceInfo(resourceName);
         }
 
-        public override string Location
-        {
-            get
-            {
-                return InternalAssembly.Location;
-            }
-        }
+        public override string Location => InternalAssembly.Location;
 
-        public override string ImageRuntimeVersion
-        {
-            get
-            {
-                return InternalAssembly.ImageRuntimeVersion;
-            }
-        }
+        public override string ImageRuntimeVersion => InternalAssembly.ImageRuntimeVersion;
 
-        public override string CodeBase
-        {
-            get
-            {
-                return InternalAssembly.CodeBase;
-            }
-        }
+        public override string CodeBase => InternalAssembly.CodeBase;
 
         /// <sumary>
         /// Override the EntryPoint method on Assembly.
         /// This doesn't need to be synchronized because it is simple enough.
         /// </sumary>
-        public override MethodInfo EntryPoint
-        {
-            get
-            {
-                return m_assemblyData.m_entryPointMethod;
-            }
-        }
+        public override MethodInfo EntryPoint => _assemblyData._entryPointMethod;
 
         /// <sumary>
         /// Get an array of all the public types defined in this assembly.
         /// </sumary>
-        public override Type[] GetExportedTypes()
-        {
-            return InternalAssembly.GetExportedTypes();
-        }
+        public override Type[] GetExportedTypes() => InternalAssembly.GetExportedTypes();
 
-        public override AssemblyName GetName(bool copiedName)
-        {
-            return InternalAssembly.GetName(copiedName);
-        }
+        public override AssemblyName GetName(bool copiedName) => InternalAssembly.GetName(copiedName);
 
-        public override string FullName
-        {
-            get
-            {
-                return InternalAssembly.FullName;
-            }
-        }
+        public override string FullName => InternalAssembly.FullName;
 
         public override Type GetType(string name, bool throwOnError, bool ignoreCase)
         {
             return InternalAssembly.GetType(name, throwOnError, ignoreCase);
         }
 
-        public override Module ManifestModule
-        {
-            get
-            {
-                return m_manifestModuleBuilder.InternalModule;
-            }
-        }
+        public override Module ManifestModule => _manifestModuleBuilder.InternalModule;
 
-        public override bool ReflectionOnly
-        {
-            get
-            {
-                return InternalAssembly.ReflectionOnly;
-            }
-        }
+        public override bool ReflectionOnly => InternalAssembly.ReflectionOnly;
 
-        public override Module GetModule(string name)
-        {
-            return InternalAssembly.GetModule(name);
-        }
+        public override Module GetModule(string name) => InternalAssembly.GetModule(name);
 
         public override AssemblyName[] GetReferencedAssemblies()
         {
             return InternalAssembly.GetReferencedAssemblies();
         }
 
-        public override bool GlobalAssemblyCache
-        {
-            get
-            {
-                return InternalAssembly.GlobalAssemblyCache;
-            }
-        }
+        public override bool GlobalAssemblyCache => InternalAssembly.GlobalAssemblyCache;
 
-        public override long HostContext
-        {
-            get
-            {
-                return InternalAssembly.HostContext;
-            }
-        }
+        public override long HostContext => InternalAssembly.HostContext;
 
         public override Module[] GetModules(bool getResourceModules)
         {
@@ -618,7 +527,7 @@ namespace System.Reflection.Emit
             return InternalAssembly.GetLoadedModules(getResourceModules);
         }
         
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
         public override Assembly GetSatelliteAssembly(CultureInfo culture)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
@@ -628,28 +537,22 @@ namespace System.Reflection.Emit
         /// <sumary> 
         /// Useful for binding to a very specific version of a satellite assembly
         /// </sumary>
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
+        [DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod.
         public override Assembly GetSatelliteAssembly(CultureInfo culture, Version version)
         {
             StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
             return InternalAssembly.InternalGetSatelliteAssembly(culture, version, ref stackMark);
         }
 
-        public override bool IsDynamic
-        {
-            get
-            {
-                return true;
-            }
-        }
+        public override bool IsDynamic => true;
 
         public override bool IsCollectible => InternalAssembly.IsCollectible;
+
         #endregion
         
         /// <param name="name">The name of module for the look up.</param>
         /// <returns>Dynamic module with the specified name.</returns>
-        public ModuleBuilder GetDynamicModule(
-            string name)
+        public ModuleBuilder GetDynamicModule(string name)
         {
             lock (SyncRoot)
             {
@@ -658,19 +561,21 @@ namespace System.Reflection.Emit
         }
 
         /// <param name="name">The name of module for the look up.</param>
-        private ModuleBuilder GetDynamicModuleNoLock(
-            string name)
+        private ModuleBuilder GetDynamicModuleNoLock(string name)
         {
             if (name == null)
+            {
                 throw new ArgumentNullException(nameof(name));
+            }
             if (name.Length == 0)
+            {
                 throw new ArgumentException(SR.Argument_EmptyName, nameof(name));
+            }
 
-            int size = m_assemblyData.m_moduleBuilderList.Count;
-            for (int i = 0; i < size; i++)
+            for (int i = 0; i < _assemblyData._moduleBuilderList.Count; i++)
             {
-                ModuleBuilder moduleBuilder = (ModuleBuilder)m_assemblyData.m_moduleBuilderList[i];
-                if (moduleBuilder.m_moduleData.m_strModuleName.Equals(name))
+                ModuleBuilder moduleBuilder = _assemblyData._moduleBuilderList[i];
+                if (moduleBuilder._moduleData._moduleName.Equals(name))
                 {
                     return moduleBuilder;
                 }
@@ -684,9 +589,13 @@ namespace System.Reflection.Emit
         public void SetCustomAttribute(ConstructorInfo con, byte[] binaryAttribute)
         {
             if (con == null)
+            {
                 throw new ArgumentNullException(nameof(con));
+            }
             if (binaryAttribute == null)
+            {
                 throw new ArgumentNullException(nameof(binaryAttribute));
+            }
 
             lock (SyncRoot)
             {
@@ -697,19 +606,12 @@ namespace System.Reflection.Emit
         private void SetCustomAttributeNoLock(ConstructorInfo con, byte[] binaryAttribute)
         {
             TypeBuilder.DefineCustomAttribute(
-                m_manifestModuleBuilder,     // pass in the in-memory assembly module
-                AssemblyBuilderData.m_tkAssembly,           // This is the AssemblyDef token
-                m_manifestModuleBuilder.GetConstructorToken(con).Token,
+                _manifestModuleBuilder,     // pass in the in-memory assembly module
+                AssemblyBuilderData.AssemblyDefToken,
+                _manifestModuleBuilder.GetConstructorToken(con).Token,
                 binaryAttribute,
                 false,
-                typeof(System.Diagnostics.DebuggableAttribute) == con.DeclaringType);
-
-            // Track the CA for persistence
-            if (m_assemblyData.m_access != AssemblyBuilderAccess.Run)
-            {
-                // tracking the CAs for persistence
-                m_assemblyData.AddCustomAttribute(con, binaryAttribute);
-            }
+                typeof(DebuggableAttribute) == con.DeclaringType);
         }
         
         /// <summary>
@@ -730,15 +632,7 @@ namespace System.Reflection.Emit
 
         private void SetCustomAttributeNoLock(CustomAttributeBuilder customBuilder)
         {
-            customBuilder.CreateCustomAttribute(
-                m_manifestModuleBuilder,
-                AssemblyBuilderData.m_tkAssembly);          // This is the AssemblyDef token 
-
-            // Track the CA for persistence
-            if (m_assemblyData.m_access != AssemblyBuilderAccess.Run)
-            {
-                m_assemblyData.AddCustomAttribute(customBuilder);
-            }
+            customBuilder.CreateCustomAttribute(_manifestModuleBuilder, AssemblyBuilderData.AssemblyDefToken);
         }
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilderData.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilderData.cs
index e2f38a226f..1eacc38d73 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilderData.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/AssemblyBuilderData.cs
@@ -2,19 +2,10 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Collections.Generic;
+
 namespace System.Reflection.Emit
 {
-    using System;
-    using IList = System.Collections.IList;
-    using System.Collections.Generic;
-    using System.Reflection;
-    using System.Security;
-    using System.Diagnostics;
-    using CultureInfo = System.Globalization.CultureInfo;
-    using System.IO;
-    using System.Runtime.Versioning;
-    using System.Diagnostics.SymbolStore;
-
     /// <summary>
     /// This is a package private class. This class hold all of the managed
     /// data member for AssemblyBuilder. Note that what ever data members added to
@@ -22,173 +13,31 @@ namespace System.Reflection.Emit
     /// </summary>
     internal class AssemblyBuilderData
     {
-        internal AssemblyBuilderData(
-            InternalAssemblyBuilder assembly,
-            string strAssemblyName,
-            AssemblyBuilderAccess access)
-        {
-            m_assembly = assembly;
-            m_strAssemblyName = strAssemblyName;
-            m_access = access;
-            m_moduleBuilderList = new List<ModuleBuilder>();
-            m_resWriterList = new List<ResWriterData>();
+        public const int AssemblyDefToken = 0x20000001;
 
-            m_peFileKind = PEFileKinds.Dll;
-        }
-        
-        /// <summary>
-        /// Helper to add a dynamic module into the tracking list.
-        /// </summary>
-        internal void AddModule(ModuleBuilder dynModule)
-        {
-            m_moduleBuilderList.Add(dynModule);
-        }
+        public readonly List<ModuleBuilder> _moduleBuilderList;
+        public readonly AssemblyBuilderAccess _access;
+        public MethodInfo _entryPointMethod;
 
-        /// <summary>
-        /// Helper to track CAs to persist onto disk.
-        /// </summary>
-        internal void AddCustomAttribute(CustomAttributeBuilder customBuilder)
-        {
-            // make sure we have room for this CA
-            if (m_CABuilders == null)
-            {
-                m_CABuilders = new CustomAttributeBuilder[m_iInitialSize];
-            }
-            if (m_iCABuilder == m_CABuilders.Length)
-            {
-                CustomAttributeBuilder[] tempCABuilders = new CustomAttributeBuilder[m_iCABuilder * 2];
-                Array.Copy(m_CABuilders, 0, tempCABuilders, 0, m_iCABuilder);
-                m_CABuilders = tempCABuilders;
-            }
-            m_CABuilders[m_iCABuilder] = customBuilder;
+        private readonly InternalAssemblyBuilder _assembly;
 
-            m_iCABuilder++;
-        }
-        
-        /// <summary>
-        /// Helper to track CAs to persist onto disk.
-        /// </summary>
-        internal void AddCustomAttribute(ConstructorInfo con, byte[] binaryAttribute)
+        internal AssemblyBuilderData(InternalAssemblyBuilder assembly, AssemblyBuilderAccess access)
         {
-            // make sure we have room for this CA
-            if (m_CABytes == null)
-            {
-                m_CABytes = new byte[m_iInitialSize][];
-                m_CACons = new ConstructorInfo[m_iInitialSize];
-            }
-            if (m_iCAs == m_CABytes.Length)
-            {
-                // enlarge the arrays
-                byte[][] temp = new byte[m_iCAs * 2][];
-                ConstructorInfo[] tempCon = new ConstructorInfo[m_iCAs * 2];
-                for (int i = 0; i < m_iCAs; i++)
-                {
-                    temp[i] = m_CABytes[i];
-                    tempCon[i] = m_CACons[i];
-                }
-                m_CABytes = temp;
-                m_CACons = tempCon;
-            }
-
-            byte[] attrs = new byte[binaryAttribute.Length];
-            Buffer.BlockCopy(binaryAttribute, 0, attrs, 0, binaryAttribute.Length);
-            m_CABytes[m_iCAs] = attrs;
-            m_CACons[m_iCAs] = con;
-            m_iCAs++;
+            _assembly = assembly;
+            _access = access;
+            _moduleBuilderList = new List<ModuleBuilder>();
         }
-        
+
         /// <summary>
         /// Helper to ensure the type name is unique underneath assemblyBuilder.
         /// </summary>
-        internal void CheckTypeNameConflict(string strTypeName, TypeBuilder enclosingType)
+        public void CheckTypeNameConflict(string strTypeName, TypeBuilder enclosingType)
         {
-            for (int i = 0; i < m_moduleBuilderList.Count; i++)
+            for (int i = 0; i < _moduleBuilderList.Count; i++)
             {
-                ModuleBuilder curModule = m_moduleBuilderList[i];
+                ModuleBuilder curModule = _moduleBuilderList[i];
                 curModule.CheckTypeNameConflict(strTypeName, enclosingType);
             }
-
-            // Right now dynamic modules can only be added to dynamic assemblies in which
-            // all modules are dynamic. Otherwise we would also need to check loaded types.
-            // We only need to make this test for non-nested types since any
-            // duplicates in nested types will be caught at the top level.
-            //      if (enclosingType == null && m_assembly.GetType(strTypeName, false, false) != null)
-            //      {
-            //          // Cannot have two types with the same name
-            //          throw new ArgumentException(SR.Argument_DuplicateTypeName);
-            //      }
         }
-
-        internal List<ModuleBuilder> m_moduleBuilderList;
-        internal List<ResWriterData> m_resWriterList;
-        internal string m_strAssemblyName;
-        internal AssemblyBuilderAccess m_access;
-        private InternalAssemblyBuilder m_assembly;
-
-        internal Type[] m_publicComTypeList;
-        internal int m_iPublicComTypeCount;
-
-        internal bool m_isSaved;
-        internal const int m_iInitialSize = 16;
-
-        // hard coding the assembly def token
-        internal const int m_tkAssembly = 0x20000001;
-
-        // tracking AssemblyDef's CAs for persistence to disk
-        internal CustomAttributeBuilder[] m_CABuilders;
-        internal int m_iCABuilder;
-        internal byte[][] m_CABytes;
-        internal ConstructorInfo[] m_CACons;
-        internal int m_iCAs;
-        internal PEFileKinds m_peFileKind;           // assembly file kind
-        internal MethodInfo m_entryPointMethod;
-        internal Assembly m_ISymWrapperAssembly;
-
-        // For unmanaged resources
-        internal string m_strResourceFileName;
-        internal byte[] m_resourceBytes;
-        internal NativeVersionInfo m_nativeVersion;
-        internal bool m_hasUnmanagedVersionInfo;
-        internal bool m_OverrideUnmanagedVersionInfo;
-    }
-
-    /// <summary>
-    /// Internal structure to track the list of ResourceWriter for
-    /// AssemblyBuilder & ModuleBuilder.
-    /// </summary>
-    internal class ResWriterData
-    {
-        internal string m_strName;
-        internal string m_strFileName;
-        internal string m_strFullFileName;
-        internal Stream m_memoryStream;
-        internal ResWriterData m_nextResWriter;
-        internal ResourceAttributes m_attribute;
-    }
-
-    internal class NativeVersionInfo
-    {
-        internal NativeVersionInfo()
-        {
-            m_strDescription = null;
-            m_strCompany = null;
-            m_strTitle = null;
-            m_strCopyright = null;
-            m_strTrademark = null;
-            m_strProduct = null;
-            m_strProductVersion = null;
-            m_strFileVersion = null;
-            m_lcid = -1;
-        }
-
-        internal string m_strDescription;
-        internal string m_strCompany;
-        internal string m_strTitle;
-        internal string m_strCopyright;
-        internal string m_strTrademark;
-        internal string m_strProduct;
-        internal string m_strProductVersion;
-        internal string m_strFileVersion;
-        internal int m_lcid;
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/ConstructorBuilder.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/ConstructorBuilder.cs
index 91e64e4f6b..895bbbc329 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/ConstructorBuilder.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/ConstructorBuilder.cs
@@ -2,18 +2,10 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-// 
+using System.Globalization;
 
 namespace System.Reflection.Emit
 {
-    using System;
-    using System.Reflection;
-    using CultureInfo = System.Globalization.CultureInfo;
-    using System.Collections.Generic;
-    using System.Diagnostics.SymbolStore;
-    using System.Security;
-    using System.Runtime.InteropServices;
-
     public sealed class ConstructorBuilder : ConstructorInfo
     {
         private readonly MethodBuilder m_methodBuilder;
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/EventToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/EventToken.cs
index 53dfa9a603..d0a406d89c 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/EventToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/EventToken.cs
@@ -2,64 +2,29 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Propertybuilder is for client to define properties for a class
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
     public struct EventToken
     {
         public static readonly EventToken Empty = new EventToken();
 
-        internal int m_event;
+        private int _token;
 
-        internal EventToken(int str)
+        internal EventToken(int eventToken)
         {
-            m_event = str;
+            _token = eventToken;
         }
 
-        public int Token
-        {
-            get { return m_event; }
-        }
+        public int Token => _token;
 
-        public override int GetHashCode()
-        {
-            return m_event;
-        }
+        public override int GetHashCode() => Token;
 
-        public override bool Equals(object obj)
-        {
-            if (obj is EventToken)
-                return Equals((EventToken)obj);
-            else
-                return false;
-        }
+        public override bool Equals(object obj) => obj is EventToken et && Equals(et);
 
-        public bool Equals(EventToken obj)
-        {
-            return obj.m_event == m_event;
-        }
+        public bool Equals(EventToken obj) => obj.Token == Token;
 
-        public static bool operator ==(EventToken a, EventToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(EventToken a, EventToken b) => a.Equals(b);
 
-        public static bool operator !=(EventToken a, EventToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(EventToken a, EventToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/FieldToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/FieldToken.cs
index b6441bf4f2..c272919f4e 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/FieldToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/FieldToken.cs
@@ -2,84 +2,37 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Purpose: Represents a Field to the ILGenerator Class
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
-    // The FieldToken class is an opaque representation of the Token returned
-    // by the Metadata to represent the field.  FieldTokens are generated by 
-    // Module.GetFieldToken().  There are no meaningful accessors on this class,
-    // but it can be passed to ILGenerator which understands it's internals.
+    /// <summary>
+    /// The FieldToken class is an opaque representation of the Token returned
+    /// by the Metadata to represent the field.  FieldTokens are generated by
+    /// Module.GetFieldToken().  There are no meaningful accessors on this class,
+    /// but it can be passed to ILGenerator which understands it's internals.
+    /// </summary>
     public struct FieldToken
     {
         public static readonly FieldToken Empty = new FieldToken();
 
-        internal int m_fieldTok;
-        internal object m_class;
-
-        // Creates an empty FieldToken.  A publicly visible constructor so that
-        // it can be created on the stack.
-        //public FieldToken() {
-        //    m_fieldTok=0;
-        //    m_attributes=0;
-        //    m_class=null;
-        //}
-        // The actual constructor.  Sets the field, attributes and class
-        // variables
-
-        internal FieldToken(int field, Type fieldClass)
-        {
-            m_fieldTok = field;
-            m_class = fieldClass;
-        }
-
-        public int Token
-        {
-            get { return m_fieldTok; }
-        }
-
+        private readonly int _token;
+        private readonly object _class;
 
-        // Generates the hash code for this field. 
-        public override int GetHashCode()
+        internal FieldToken(int fieldToken, Type fieldClass)
         {
-            return (m_fieldTok);
+            _token = fieldToken;
+            _class = fieldClass;
         }
 
-        // Returns true if obj is an instance of FieldToken and is 
-        // equal to this instance.
-        public override bool Equals(object obj)
-        {
-            if (obj is FieldToken)
-                return Equals((FieldToken)obj);
-            else
-                return false;
-        }
+        public int Token => _token;
+        
+        public override int GetHashCode() => Token;
+        
+        public override bool Equals(object obj) => obj is FieldToken ft && Equals(ft);
 
-        public bool Equals(FieldToken obj)
-        {
-            return obj.m_fieldTok == m_fieldTok && obj.m_class == m_class;
-        }
+        public bool Equals(FieldToken obj) => obj.Token == Token && obj._class == _class;
 
-        public static bool operator ==(FieldToken a, FieldToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(FieldToken a, FieldToken b) => a.Equals(b);
 
-        public static bool operator !=(FieldToken a, FieldToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(FieldToken a, FieldToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/MethodToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/MethodToken.cs
index 2c0a91872e..3546041e0b 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/MethodToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/MethodToken.cs
@@ -2,63 +2,29 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Purpose: Represents a Method to the ILGenerator class.
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
     public struct MethodToken
     {
         public static readonly MethodToken Empty = new MethodToken();
-        internal int m_method;
 
-        internal MethodToken(int str)
-        {
-            m_method = str;
-        }
+        private readonly int _token;
 
-        public int Token
+        internal MethodToken(int methodToken)
         {
-            get { return m_method; }
+            _token = methodToken;
         }
 
-        public override int GetHashCode()
-        {
-            return m_method;
-        }
+        public int Token => _token;
 
-        public override bool Equals(object obj)
-        {
-            if (obj is MethodToken)
-                return Equals((MethodToken)obj);
-            else
-                return false;
-        }
+        public override int GetHashCode() => Token;
 
-        public bool Equals(MethodToken obj)
-        {
-            return obj.m_method == m_method;
-        }
+        public override bool Equals(object obj) => obj is MethodToken mt && Equals(mt);
 
-        public static bool operator ==(MethodToken a, MethodToken b)
-        {
-            return a.Equals(b);
-        }
+        public bool Equals(MethodToken obj) => obj.Token == Token;
 
-        public static bool operator !=(MethodToken a, MethodToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator ==(MethodToken a, MethodToken b) => a.Equals(b);
+
+        public static bool operator !=(MethodToken a, MethodToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilder.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilder.cs
index d0b8c87ab0..8b0beb11c9 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilder.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilder.cs
@@ -2,62 +2,45 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-// 
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Diagnostics.SymbolStore;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 
 namespace System.Reflection.Emit
 {
-    using System.Runtime.InteropServices;
-    using System;
-    using System.Collections.Generic;
-    using System.Diagnostics.SymbolStore;
-    using System.Globalization;
-    using System.Reflection;
-    using System.IO;
-    using System.Resources;
-    using System.Security;
-    using System.Runtime.Serialization;
-    using System.Text;
-    using System.Threading;
-    using System.Runtime.Versioning;
-    using System.Runtime.CompilerServices;
-    using System.Diagnostics;
-
     internal sealed class InternalModuleBuilder : RuntimeModule
     {
-        #region Private Data Members
-        // WARNING!! WARNING!!
         // InternalModuleBuilder should not contain any data members as its reflectbase is the same as Module.
-        #endregion
 
         private InternalModuleBuilder() { }
 
-        #region object overrides
         public override bool Equals(object obj)
         {
             if (obj == null)
+            {
                 return false;
+            }
 
             if (obj is InternalModuleBuilder)
+            {
                 return ((object)this == obj);
+            }
 
             return obj.Equals(this);
         }
+
         // Need a dummy GetHashCode to pair with Equals
-        public override int GetHashCode() { return base.GetHashCode(); }
-        #endregion
+        public override int GetHashCode() => base.GetHashCode();
     }
 
     // deliberately not [serializable]
     public class ModuleBuilder : Module
     {
-        #region FCalls
-
-        [MethodImplAttribute(MethodImplOptions.InternalCall)]
+        [MethodImpl(MethodImplOptions.InternalCall)]
         internal static extern IntPtr nCreateISymWriterForDynamicModule(Module module, string filename);
 
-        #endregion
-
-        #region Internal Static Members
         internal static string UnmangleTypeName(string typeName)
         {
             // Gets the original type name, without '+' name mangling.
@@ -67,16 +50,22 @@ namespace System.Reflection.Emit
             {
                 i = typeName.LastIndexOf('+', i);
                 if (i == -1)
+                {
                     break;
+                }
 
                 bool evenSlashes = true;
                 int iSlash = i;
                 while (typeName[--iSlash] == '\\')
+                {
                     evenSlashes = !evenSlashes;
+                }
 
                 // Even number of slashes means this '+' is a name separator
                 if (evenSlashes)
+                {
                     break;
+                }
 
                 i = iSlash;
             }
@@ -84,39 +73,37 @@ namespace System.Reflection.Emit
             return typeName.Substring(i + 1);
         }
 
-        #endregion
-
         #region Internal Data Members
-        // m_TypeBuilder contains both TypeBuilder and EnumBuilder objects
-        private Dictionary<string, Type> m_TypeBuilderDict;
-        private ISymbolWriter m_iSymWriter;
-        internal ModuleBuilderData m_moduleData;
-        internal InternalModuleBuilder m_internalModuleBuilder;
+
+        // _TypeBuilder contains both TypeBuilder and EnumBuilder objects
+        private Dictionary<string, Type> _typeBuilderDict;
+        private ISymbolWriter _iSymWriter;
+        internal ModuleBuilderData _moduleData;
+        internal InternalModuleBuilder _internalModuleBuilder;
         // This is the "external" AssemblyBuilder
         // only the "external" ModuleBuilder has this set
-        private AssemblyBuilder m_assemblyBuilder;
-        internal AssemblyBuilder ContainingAssemblyBuilder { get { return m_assemblyBuilder; } }
+        private readonly AssemblyBuilder _assemblyBuilder;
+        internal AssemblyBuilder ContainingAssemblyBuilder => _assemblyBuilder;
+
         #endregion
 
         #region Constructor
+
         internal ModuleBuilder(AssemblyBuilder assemblyBuilder, InternalModuleBuilder internalModuleBuilder)
         {
-            m_internalModuleBuilder = internalModuleBuilder;
-            m_assemblyBuilder = assemblyBuilder;
+            _internalModuleBuilder = internalModuleBuilder;
+            _assemblyBuilder = assemblyBuilder;
         }
+
         #endregion
 
         #region Private Members
-        internal void AddType(string name, Type type)
-        {
-            m_TypeBuilderDict.Add(name, type);
-        }
+        internal void AddType(string name, Type type) => _typeBuilderDict.Add(name, type);
 
         internal void CheckTypeNameConflict(string strTypeName, Type enclosingType)
         {
-            Type foundType = null;
-            if (m_TypeBuilderDict.TryGetValue(strTypeName, out foundType) &&
-                object.ReferenceEquals(foundType.DeclaringType, enclosingType))
+            if (_typeBuilderDict.TryGetValue(strTypeName, out Type foundType) &&
+                ReferenceEquals(foundType.DeclaringType, enclosingType))
             {
                 // Cannot have two types with the same name
                 throw new ArgumentException(SR.Argument_DuplicateTypeName);
@@ -126,7 +113,6 @@ namespace System.Reflection.Emit
         private Type GetType(string strFormat, Type baseType)
         {
             // This function takes a string to describe the compound type, such as "[,][]", and a baseType.
-
             if (strFormat == null || strFormat.Equals(string.Empty))
             {
                 return baseType;
@@ -136,7 +122,6 @@ namespace System.Reflection.Emit
             return SymbolType.FormCompoundType(strFormat, baseType, 0);
         }
 
-
         internal void CheckContext(params Type[][] typess)
         {
             ContainingAssemblyBuilder.CheckContext(typess);
@@ -146,7 +131,6 @@ namespace System.Reflection.Emit
             ContainingAssemblyBuilder.CheckContext(types);
         }
 
-
         [DllImport(JitHelpers.QCall, CharSet = CharSet.Unicode)]
         private static extern int GetTypeRef(RuntimeModule module, string strFullName, RuntimeModule refedModule, string strRefedModuleFileName, int tkResolution);
 
@@ -213,21 +197,25 @@ namespace System.Reflection.Emit
         #endregion
 
         #region Internal Members
+
         internal virtual Type FindTypeBuilderWithName(string strTypeName, bool ignoreCase)
         {
             if (ignoreCase)
             {
-                foreach (string name in m_TypeBuilderDict.Keys)
+                foreach (string name in _typeBuilderDict.Keys)
                 {
                     if (string.Equals(name, strTypeName, StringComparison.OrdinalIgnoreCase))
-                        return m_TypeBuilderDict[name];
+                    {
+                        return _typeBuilderDict[name];
+                    }
                 }
             }
             else
             {
-                Type foundType;
-                if (m_TypeBuilderDict.TryGetValue(strTypeName, out foundType))
+                if (_typeBuilderDict.TryGetValue(strTypeName, out Type foundType))
+                {
                     return foundType;
+                }
             }
 
             return null;
@@ -236,7 +224,6 @@ namespace System.Reflection.Emit
         private int GetTypeRefNested(Type type, Module refedModule, string strRefedModuleFileName)
         {
             // This function will generate correct TypeRef token for top level type and nested type.
-
             Type enclosingType = type.DeclaringType;
             int tkResolution = 0;
             string typeName = type.FullName;
@@ -256,9 +243,10 @@ namespace System.Reflection.Emit
         internal MethodToken InternalGetConstructorToken(ConstructorInfo con, bool usingRef)
         {
             // Helper to get constructor token. If usingRef is true, we will never use the def token
-
             if (con == null)
+            {
                 throw new ArgumentNullException(nameof(con));
+            }
 
             int tr;
             int mr = 0;
@@ -287,7 +275,6 @@ namespace System.Reflection.Emit
             {
                 // constructor is not a dynamic field
                 // We need to get the TypeRef tokens
-
                 tr = GetTypeTokenInternal(con.ReflectedType).Token;
                 mr = GetMemberRefOfMethodInfo(tr, rtCon);
             }
@@ -297,7 +284,9 @@ namespace System.Reflection.Emit
                 // go through the slower code path, i.e. retrieve parameters and form signature helper.
                 ParameterInfo[] parameters = con.GetParameters();
                 if (parameters == null)
+                {
                     throw new ArgumentException(SR.Argument_InvalidConstructorInfo);
+                }
 
                 Type[] parameterTypes = new Type[parameters.Length];
                 Type[][] requiredCustomModifiers = new Type[parameters.Length][];
@@ -306,7 +295,9 @@ namespace System.Reflection.Emit
                 for (int i = 0; i < parameters.Length; i++)
                 {
                     if (parameters[i] == null)
+                    {
                         throw new ArgumentException(SR.Argument_InvalidConstructorInfo);
+                    }
 
                     parameterTypes[i] = parameters[i].ParameterType;
                     requiredCustomModifiers[i] = parameters[i].GetRequiredCustomModifiers();
@@ -316,56 +307,33 @@ namespace System.Reflection.Emit
                 tr = GetTypeTokenInternal(con.ReflectedType).Token;
 
                 SignatureHelper sigHelp = SignatureHelper.GetMethodSigHelper(this, con.CallingConvention, null, null, null, parameterTypes, requiredCustomModifiers, optionalCustomModifiers);
-                int length;
-                byte[] sigBytes = sigHelp.InternalGetSignature(out length);
-
+                byte[] sigBytes = sigHelp.InternalGetSignature(out int length);
                 mr = GetMemberRefFromSignature(tr, con.Name, sigBytes, length);
             }
 
             return new MethodToken(mr);
         }
 
-        internal void Init(string strModuleName, string strFileName, int tkFile)
+        internal void Init(string strModuleName)
         {
-            m_moduleData = new ModuleBuilderData(this, strModuleName, strFileName, tkFile);
-            m_TypeBuilderDict = new Dictionary<string, Type>();
+            _moduleData = new ModuleBuilderData(this, strModuleName);
+            _typeBuilderDict = new Dictionary<string, Type>();
         }
 
-        internal void SetSymWriter(ISymbolWriter writer)
-        {
-            m_iSymWriter = writer;
-        }
+        internal void SetSymWriter(ISymbolWriter writer) => _iSymWriter = writer;
 
-        internal object SyncRoot
-        {
-            get
-            {
-                return ContainingAssemblyBuilder.SyncRoot;
-            }
-        }
+        internal object SyncRoot => ContainingAssemblyBuilder.SyncRoot;
 
         #endregion
 
         #region Module Overrides
 
-        // m_internalModuleBuilder is null iff this is a "internal" ModuleBuilder
-        internal InternalModuleBuilder InternalModule
-        {
-            get
-            {
-                return m_internalModuleBuilder;
-            }
-        }
+        // _internalModuleBuilder is null iff this is a "internal" ModuleBuilder
+        internal InternalModuleBuilder InternalModule => _internalModuleBuilder;
 
-        protected override ModuleHandle GetModuleHandleImpl()
-        {
-            return new ModuleHandle(GetNativeHandle());
-        }
+        protected override ModuleHandle GetModuleHandleImpl() => new ModuleHandle(GetNativeHandle());
 
-        internal RuntimeModule GetNativeHandle()
-        {
-            return InternalModule.GetNativeHandle();
-        }
+        internal RuntimeModule GetNativeHandle() => InternalModule.GetNativeHandle();
 
         private static RuntimeModule GetRuntimeModuleFromModule(Module m)
         {
@@ -388,7 +356,9 @@ namespace System.Reflection.Emit
             if (method.IsGenericMethod)
             {
                 if (!method.IsGenericMethodDefinition)
+                {
                     throw new InvalidOperationException();
+                }
 
                 cGenericParameters = method.GetGenericArguments().Length;
             }
@@ -435,14 +405,14 @@ namespace System.Reflection.Emit
                         methDef = masmi.GetGenericMethodDefinition();
                         methDef = methDef.Module.ResolveMethod(
                             method.MetadataToken,
-                            methDef.DeclaringType != null ? methDef.DeclaringType.GetGenericArguments() : null,
+                            methDef.DeclaringType?.GetGenericArguments(),
                             methDef.GetGenericArguments());
                     }
                     else
                     {
                         methDef = method.Module.ResolveMethod(
                             method.MetadataToken,
-                            method.DeclaringType != null ? method.DeclaringType.GetGenericArguments() : null,
+                            method.DeclaringType?.GetGenericArguments(),
                             null);
                     }
                 }
@@ -456,14 +426,12 @@ namespace System.Reflection.Emit
                 returnType = MethodBuilder.GetMethodBaseReturnType(method);
             }
 
-            int sigLength;
             byte[] sigBytes = GetMemberRefSignature(method.CallingConvention, returnType, parameterTypes,
-                optionalParameterTypes, cGenericParameters).InternalGetSignature(out sigLength);
+                optionalParameterTypes, cGenericParameters).InternalGetSignature(out int sigLength);
 
             if (method.DeclaringType.IsGenericType)
             {
-                int length;
-                byte[] sig = SignatureHelper.GetTypeSigToken(this, method.DeclaringType).InternalGetSignature(out length);
+                byte[] sig = SignatureHelper.GetTypeSigToken(this, method.DeclaringType).InternalGetSignature(out int length);
                 tkParent = GetTokenFromTypeSpec(sig, length);
             }
             else if (!method.Module.Equals(this))
@@ -517,16 +485,13 @@ namespace System.Reflection.Emit
 
         #endregion
 
-        #region object overrides
-        public override bool Equals(object obj)
-        {
-            return InternalModule.Equals(obj);
-        }
+        public override bool Equals(object obj) => InternalModule.Equals(obj);
+
         // Need a dummy GetHashCode to pair with Equals
-        public override int GetHashCode() { return InternalModule.GetHashCode(); }
-        #endregion
+        public override int GetHashCode() => InternalModule.GetHashCode();
 
         #region ICustomAttributeProvider Members
+
         public override object[] GetCustomAttributes(bool inherit)
         {
             return InternalModule.GetCustomAttributes(inherit);
@@ -546,6 +511,7 @@ namespace System.Reflection.Emit
         {
             return InternalModule.GetCustomAttributesData();
         }
+
         #endregion
 
         #region Module Overrides
@@ -560,11 +526,11 @@ namespace System.Reflection.Emit
 
         internal Type[] GetTypesNoLock()
         {
-            int size = m_TypeBuilderDict.Count;
-            Type[] typeList = new Type[m_TypeBuilderDict.Count];
+            int size = _typeBuilderDict.Count;
+            Type[] typeList = new Type[_typeBuilderDict.Count];
             int i = 0;
 
-            foreach (Type builder in m_TypeBuilderDict.Values)
+            foreach (Type builder in _typeBuilderDict.Values)
             {
                 EnumBuilder enumBldr = builder as EnumBuilder;
                 TypeBuilder tmpTypeBldr;
@@ -668,7 +634,6 @@ namespace System.Reflection.Emit
             {
                 // try to see if reflection can find the base type. It can be such that reflection
                 // does not support the complex format string yet!
-
                 baseType = InternalModule.GetType(baseName, false, ignoreCase);
             }
 
@@ -683,7 +648,7 @@ namespace System.Reflection.Emit
                     int size;
                     List<ModuleBuilder> modList;
 
-                    modList = ContainingAssemblyBuilder.m_assemblyData.m_moduleBuilderList;
+                    modList = ContainingAssemblyBuilder._assemblyData._moduleBuilderList;
                     size = modList.Count;
                     for (int i = 0; i < size && baseType == null; i++)
                     {
@@ -692,22 +657,20 @@ namespace System.Reflection.Emit
                     }
                 }
                 if (baseType == null)
+                {
                     return null;
+                }
             }
 
             if (parameters == null)
+            {
                 return baseType;
+            }
 
             return GetType(parameters, baseType);
         }
 
-        public override string FullyQualifiedName
-        {
-            get
-            {
-                return m_moduleData.m_strFileName;
-            }
-        }
+        public override string FullyQualifiedName => _moduleData._moduleName;
 
         public override byte[] ResolveSignature(int metadataToken)
         {
@@ -744,34 +707,13 @@ namespace System.Reflection.Emit
             InternalModule.GetPEKind(out peKind, out machine);
         }
 
-        public override int MDStreamVersion
-        {
-            get
-            {
-                return InternalModule.MDStreamVersion;
-            }
-        }
+        public override int MDStreamVersion => InternalModule.MDStreamVersion;
 
-        public override Guid ModuleVersionId
-        {
-            get
-            {
-                return InternalModule.ModuleVersionId;
-            }
-        }
+        public override Guid ModuleVersionId => InternalModule.ModuleVersionId;
 
-        public override int MetadataToken
-        {
-            get
-            {
-                return InternalModule.MetadataToken;
-            }
-        }
+        public override int MetadataToken => InternalModule.MetadataToken;
 
-        public override bool IsResource()
-        {
-            return InternalModule.IsResource();
-        }
+        public override bool IsResource() => InternalModule.IsResource();
 
         public override FieldInfo[] GetFields(BindingFlags bindingFlags)
         {
@@ -795,35 +737,18 @@ namespace System.Reflection.Emit
             return InternalModule.GetMethodInternal(name, bindingAttr, binder, callConvention, types, modifiers);
         }
 
-        public override string ScopeName
-        {
-            get
-            {
-                return InternalModule.ScopeName;
-            }
-        }
+        public override string ScopeName => InternalModule.ScopeName;
 
-        public override string Name
-        {
-            get
-            {
-                return InternalModule.Name;
-            }
-        }
+        public override string Name => InternalModule.Name;
 
-        public override Assembly Assembly
-        {
-            get
-            {
-                return m_assemblyBuilder;
-            }
-        }
+        public override Assembly Assembly => _assemblyBuilder;
 
         #endregion
 
         #region Public Members
 
         #region Define Type
+
         public TypeBuilder DefineType(string name)
         {
             lock (SyncRoot)
@@ -844,7 +769,6 @@ namespace System.Reflection.Emit
         {
             lock (SyncRoot)
             {
-                // Why do we only call CheckContext here? Why don't we call it in the other overloads?
                 CheckContext(parent);
 
                 return DefineTypeNoLock(name, attr, parent, null, PackingSize.Unspecified, TypeBuilder.UnspecifiedTypeSize);
@@ -907,17 +831,8 @@ namespace System.Reflection.Emit
                 EnumBuilder enumBuilder = DefineEnumNoLock(name, visibility, underlyingType);
 
                 // This enum is not generic, nested, and cannot have any element type.
-
-                // We ought to be able to make the following assertions:
-                //
-                //  Debug.Assert(name == enumBuilder.FullName);
-                //  Debug.Assert(enumBuilder.m_typeBuilder == m_TypeBuilderDict[name]);
-                //
-                // but we can't because an embedded null ('\0') in the name will cause it to be truncated
-                // incorrectly.  Fixing that would be a breaking change.
-
-                // Replace the TypeBuilder object in m_TypeBuilderDict with this EnumBuilder object.
-                m_TypeBuilderDict[name] = enumBuilder;
+                // Replace the TypeBuilder object in _typeBuilderDict with this EnumBuilder object.
+                _typeBuilderDict[name] = enumBuilder;
 
                 return enumBuilder;
             }
@@ -930,9 +845,6 @@ namespace System.Reflection.Emit
 
         #endregion
 
-        #region Define Resource
-
-        #endregion
         #region Define Global Method
 
         public MethodBuilder DefinePInvokeMethod(string name, string dllName, MethodAttributes attributes,
@@ -948,7 +860,7 @@ namespace System.Reflection.Emit
         {
             lock (SyncRoot)
             {
-                //Global methods must be static.        
+                // Global methods must be static.
                 if ((attributes & MethodAttributes.Static) == 0)
                 {
                     throw new ArgumentException(SR.Argument_GlobalFunctionHasToBeStatic);
@@ -957,8 +869,7 @@ namespace System.Reflection.Emit
                 CheckContext(returnType);
                 CheckContext(parameterTypes);
 
-                m_moduleData.m_fHasGlobal = true;
-                return m_moduleData.m_globalTypeBuilder.DefinePInvokeMethod(name, dllName, entryName, attributes, callingConvention, returnType, parameterTypes, nativeCallConv, nativeCharSet);
+                return _moduleData._globalTypeBuilder.DefinePInvokeMethod(name, dllName, entryName, attributes, callingConvention, returnType, parameterTypes, nativeCallConv, nativeCharSet);
             }
         }
 
@@ -989,26 +900,29 @@ namespace System.Reflection.Emit
             Type returnType, Type[] requiredReturnTypeCustomModifiers, Type[] optionalReturnTypeCustomModifiers,
             Type[] parameterTypes, Type[][] requiredParameterTypeCustomModifiers, Type[][] optionalParameterTypeCustomModifiers)
         {
-            if (m_moduleData.m_fGlobalBeenCreated == true)
+            if (_moduleData._hasGlobalBeenCreated)
+            {
                 throw new InvalidOperationException(SR.InvalidOperation_GlobalsHaveBeenCreated);
-
+            }
             if (name == null)
+            {
                 throw new ArgumentNullException(nameof(name));
-
+            }
             if (name.Length == 0)
+            {
                 throw new ArgumentException(SR.Argument_EmptyName, nameof(name));
-
+            }
             if ((attributes & MethodAttributes.Static) == 0)
+            {
                 throw new ArgumentException(SR.Argument_GlobalFunctionHasToBeStatic);
+            }
 
             CheckContext(returnType);
             CheckContext(requiredReturnTypeCustomModifiers, optionalReturnTypeCustomModifiers, parameterTypes);
             CheckContext(requiredParameterTypeCustomModifiers);
             CheckContext(optionalParameterTypeCustomModifiers);
 
-            m_moduleData.m_fHasGlobal = true;
-
-            return m_moduleData.m_globalTypeBuilder.DefineMethod(name, attributes, callingConvention,
+            return _moduleData._globalTypeBuilder.DefineMethod(name, attributes, callingConvention,
                 returnType, requiredReturnTypeCustomModifiers, optionalReturnTypeCustomModifiers,
                 parameterTypes, requiredParameterTypeCustomModifiers, optionalParameterTypeCustomModifiers);
         }
@@ -1023,13 +937,13 @@ namespace System.Reflection.Emit
 
         private void CreateGlobalFunctionsNoLock()
         {
-            if (m_moduleData.m_fGlobalBeenCreated)
+            if (_moduleData._hasGlobalBeenCreated)
             {
                 // cannot create globals twice
                 throw new InvalidOperationException(SR.InvalidOperation_NotADebugModule);
             }
-            m_moduleData.m_globalTypeBuilder.CreateType();
-            m_moduleData.m_fGlobalBeenCreated = true;
+            _moduleData._globalTypeBuilder.CreateType();
+            _moduleData._hasGlobalBeenCreated = true;
         }
 
         #endregion
@@ -1053,13 +967,12 @@ namespace System.Reflection.Emit
             // This method will define an initialized Data in .sdata. 
             // We will create a fake TypeDef to represent the data with size. This TypeDef
             // will be the signature for the Field.
-            if (m_moduleData.m_fGlobalBeenCreated == true)
+            if (_moduleData._hasGlobalBeenCreated == true)
             {
                 throw new InvalidOperationException(SR.InvalidOperation_GlobalsHaveBeenCreated);
             }
 
-            m_moduleData.m_fHasGlobal = true;
-            return m_moduleData.m_globalTypeBuilder.DefineInitializedData(name, data, attributes);
+            return _moduleData._globalTypeBuilder.DefineInitializedData(name, data, attributes);
         }
 
         public FieldBuilder DefineUninitializedData(string name, int size, FieldAttributes attributes)
@@ -1076,25 +989,25 @@ namespace System.Reflection.Emit
             // We will create a fake TypeDef to represent the data with size. This TypeDef
             // will be the signature for the Field. 
 
-            if (m_moduleData.m_fGlobalBeenCreated == true)
+            if (_moduleData._hasGlobalBeenCreated)
             {
                 throw new InvalidOperationException(SR.InvalidOperation_GlobalsHaveBeenCreated);
             }
 
-            m_moduleData.m_fHasGlobal = true;
-            return m_moduleData.m_globalTypeBuilder.DefineUninitializedData(name, size, attributes);
+            return _moduleData._globalTypeBuilder.DefineUninitializedData(name, size, attributes);
         }
 
         #endregion
 
         #region GetToken
+
         // For a generic type definition, we should return the token for the generic type definition itself in two cases: 
         //   1. GetTypeToken
         //   2. ldtoken (see ILGenerator)
         // For all other occasions we should return the generic type instantiated on its formal parameters.
         internal TypeToken GetTypeTokenInternal(Type type)
         {
-            return GetTypeTokenInternal(type, false);
+            return GetTypeTokenInternal(type, getGenericDefinition: false);
         }
 
         private TypeToken GetTypeTokenInternal(Type type, bool getGenericDefinition)
@@ -1107,13 +1020,15 @@ namespace System.Reflection.Emit
 
         public TypeToken GetTypeToken(Type type)
         {
-            return GetTypeTokenInternal(type, true);
+            return GetTypeTokenInternal(type, getGenericDefinition: true);
         }
 
         private TypeToken GetTypeTokenWorkerNoLock(Type type, bool getGenericDefinition)
         {
             if (type == null)
+            {
                 throw new ArgumentNullException(nameof(type));
+            }
 
             CheckContext(type);
 
@@ -1126,17 +1041,17 @@ namespace System.Reflection.Emit
             // multiple calles to this method with the same class have no additional side affects.
             // This function is optimized to use the TypeDef token if Type is within the same module.
             // We should also be aware of multiple dynamic modules and multiple implementation of Type!!!
-
             if (type.IsByRef)
+            {
                 throw new ArgumentException(SR.Argument_CannotGetTypeTokenForByRef);
+            }
 
             if ((type.IsGenericType && (!type.IsGenericTypeDefinition || !getGenericDefinition)) ||
                 type.IsGenericParameter ||
                 type.IsArray ||
                 type.IsPointer)
             {
-                int length;
-                byte[] sig = SignatureHelper.GetTypeSigToken(this, type).InternalGetSignature(out length);
+                byte[] sig = SignatureHelper.GetTypeSigToken(this, type).InternalGetSignature(out int length);
                 return new TypeToken(GetTokenFromTypeSpec(sig, length));
             }
 
@@ -1149,16 +1064,11 @@ namespace System.Reflection.Emit
                 GenericTypeParameterBuilder paramBuilder = null;
 
                 EnumBuilder enumBuilder = type as EnumBuilder;
-                if (enumBuilder != null)
-                    typeBuilder = enumBuilder.m_typeBuilder;
-                else
-                    typeBuilder = type as TypeBuilder;
+                typeBuilder = enumBuilder != null ? enumBuilder.m_typeBuilder : type as TypeBuilder;
 
                 if (typeBuilder != null)
                 {
-                    // optimization: if the type is defined in this module,
-                    // just return the token
-                    //
+                    // If the type is defined in this module, just return the token.
                     return typeBuilder.TypeToken;
                 }
                 else if ((paramBuilder = type as GenericTypeParameterBuilder) != null)
@@ -1171,11 +1081,10 @@ namespace System.Reflection.Emit
 
             // After this point, the referenced module is not the same as the referencing
             // module.
-            //
             ModuleBuilder refedModuleBuilder = refedModule as ModuleBuilder;
 
-            string strRefedModuleFileName = string.Empty;
-            if (refedModule.Assembly.Equals(this.Assembly))
+            string referencedModuleFileName = string.Empty;
+            if (refedModule.Assembly.Equals(Assembly))
             {
                 // if the referenced module is in the same assembly, the resolution
                 // scope of the type token will be a module ref, we will need
@@ -1185,12 +1094,12 @@ namespace System.Reflection.Emit
                 // the file name of the referenced module.
                 if (refedModuleBuilder == null)
                 {
-                    refedModuleBuilder = this.ContainingAssemblyBuilder.GetModuleBuilder((InternalModuleBuilder)refedModule);
+                    refedModuleBuilder = ContainingAssemblyBuilder.GetModuleBuilder((InternalModuleBuilder)refedModule);
                 }
-                strRefedModuleFileName = refedModuleBuilder.m_moduleData.m_strFileName;
+                referencedModuleFileName = refedModuleBuilder._moduleData._moduleName;
             }
 
-            return new TypeToken(GetTypeRefNested(type, refedModule, strRefedModuleFileName));
+            return new TypeToken(GetTypeRefNested(type, refedModule, referencedModuleFileName));
         }
 
         public TypeToken GetTypeToken(string name)
@@ -1229,7 +1138,9 @@ namespace System.Reflection.Emit
             // Return a MemberRef token if MethodInfo is not defined in this module. Or 
             // return the MethodDef token. 
             if (method == null)
+            {
                 throw new ArgumentNullException(nameof(method));
+            }
 
             int tr;
             int mr = 0;
@@ -1241,10 +1152,14 @@ namespace System.Reflection.Emit
             {
                 int methodToken = methBuilder.MetadataTokenInternal;
                 if (method.Module.Equals(this))
+                {
                     return new MethodToken(methodToken);
+                }
 
                 if (method.DeclaringType == null)
+                {
                     throw new InvalidOperationException(SR.InvalidOperation_CannotImportGlobalFromDifferentModule);
+                }
 
                 // method is defined in a different module
                 tr = getGenericTypeDefinition ? GetTypeToken(method.DeclaringType).Token : GetTypeTokenInternal(method.DeclaringType).Token;
@@ -1268,7 +1183,9 @@ namespace System.Reflection.Emit
 
                 // We need to get the TypeRef tokens
                 if (declaringType == null)
+                {
                     throw new InvalidOperationException(SR.InvalidOperation_CannotImportGlobalFromDifferentModule);
+                }
 
                 RuntimeMethodInfo rtMeth = null;
 
@@ -1323,8 +1240,7 @@ namespace System.Reflection.Emit
                         sigHelp = SignatureHelper.GetMethodSigHelper(this, method.ReturnType, parameterTypes);
                     }
 
-                    int length;
-                    byte[] sigBytes = sigHelp.InternalGetSignature(out length);
+                    byte[] sigBytes = sigHelp.InternalGetSignature(out int length);
                     mr = GetMemberRefFromSignature(tr, method.Name, sigBytes, length);
                 }
             }
@@ -1351,7 +1267,7 @@ namespace System.Reflection.Emit
                     methodInfoUnbound = methodInfo.GetGenericMethodDefinition();
                 }
 
-                if (!this.Equals(methodInfoUnbound.Module)
+                if (!Equals(methodInfoUnbound.Module)
                     || (methodInfoUnbound.DeclaringType != null && methodInfoUnbound.DeclaringType.IsGenericType))
                 {
                     tk = GetMemberRefToken(methodInfoUnbound, null);
@@ -1368,12 +1284,10 @@ namespace System.Reflection.Emit
                 }
 
                 // Create signature of method instantiation M<Bar>
-                int sigLength;
-                byte[] sigBytes = SignatureHelper.GetMethodSpecSigHelper(
-                    this, methodInfo.GetGenericArguments()).InternalGetSignature(out sigLength);
-
                 // Create MethodSepc M<Bar> with parent G?.M<S> 
-                tk = TypeBuilder.DefineMethodSpec(this.GetNativeHandle(), tk, sigBytes, sigLength);
+                byte[] sigBytes = SignatureHelper.GetMethodSpecSigHelper(
+                    this, methodInfo.GetGenericArguments()).InternalGetSignature(out int sigLength);
+                tk = TypeBuilder.DefineMethodSpec(GetNativeHandle(), tk, sigBytes, sigLength);
             }
             else
             {
@@ -1411,30 +1325,30 @@ namespace System.Reflection.Emit
             Type returnType, Type[] parameterTypes)
         {
             if (arrayClass == null)
+            {
                 throw new ArgumentNullException(nameof(arrayClass));
-
+            }
             if (methodName == null)
+            {
                 throw new ArgumentNullException(nameof(methodName));
-
+            }
             if (methodName.Length == 0)
+            {
                 throw new ArgumentException(SR.Argument_EmptyName, nameof(methodName));
-
-            if (arrayClass.IsArray == false)
+            }
+            if (!arrayClass.IsArray)
+            {
                 throw new ArgumentException(SR.Argument_HasToBeArrayClass);
+            }
 
             CheckContext(returnType, arrayClass);
             CheckContext(parameterTypes);
 
             // Return a token for the MethodInfo for a method on an Array.  This is primarily
             // used to get the LoadElementAddress method. 
-
-            int length;
-
             SignatureHelper sigHelp = SignatureHelper.GetMethodSigHelper(
                 this, callingConvention, returnType, null, null, parameterTypes, null, null);
-
-            byte[] sigBytes = sigHelp.InternalGetSignature(out length);
-
+            byte[] sigBytes = sigHelp.InternalGetSignature(out int length);
             TypeToken typeSpec = GetTypeTokenInternal(arrayClass);
 
             return new MethodToken(GetArrayMethodToken(GetNativeHandle(),
@@ -1489,8 +1403,7 @@ namespace System.Reflection.Emit
             {
                 if (field.DeclaringType != null && field.DeclaringType.IsGenericType)
                 {
-                    int length;
-                    byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out length);
+                    byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out int length);
                     tr = GetTokenFromTypeSpec(sig, length);
                     mr = GetMemberRef(this, tr, fdBuilder.GetToken().Token);
                 }
@@ -1513,7 +1426,6 @@ namespace System.Reflection.Emit
             else if ((rtField = field as RuntimeFieldInfo) != null)
             {
                 // FieldInfo is not an dynamic field
-
                 // We need to get the TypeRef tokens
                 if (field.DeclaringType == null)
                 {
@@ -1522,8 +1434,7 @@ namespace System.Reflection.Emit
 
                 if (field.DeclaringType != null && field.DeclaringType.IsGenericType)
                 {
-                    int length;
-                    byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out length);
+                    byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out int length);
                     tr = GetTokenFromTypeSpec(sig, length);
                     mr = GetMemberRefOfFieldInfo(tr, field.DeclaringType.GetTypeHandleInternal(), rtField);
                 }
@@ -1536,8 +1447,7 @@ namespace System.Reflection.Emit
             else if ((fOnTB = field as FieldOnTypeBuilderInstantiation) != null)
             {
                 FieldInfo fb = fOnTB.FieldInfo;
-                int length;
-                byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out length);
+                byte[] sig = SignatureHelper.GetTypeSigToken(this, field.DeclaringType).InternalGetSignature(out int length);
                 tr = GetTokenFromTypeSpec(sig, length);
                 mr = GetMemberRef(fb.ReflectedType.Module, tr, fOnTB.MetadataTokenInternal);
             }
@@ -1550,9 +1460,7 @@ namespace System.Reflection.Emit
 
                 sigHelp.AddArgument(field.FieldType, field.GetRequiredCustomModifiers(), field.GetOptionalCustomModifiers());
 
-                int length;
-                byte[] sigBytes = sigHelp.InternalGetSignature(out length);
-
+                byte[] sigBytes = sigHelp.InternalGetSignature(out int length);
                 mr = GetMemberRefFromSignature(tr, field.Name, sigBytes, length);
             }
 
@@ -1575,28 +1483,27 @@ namespace System.Reflection.Emit
         {
             // Define signature token given a signature helper. This will define a metadata
             // token for the signature described by SignatureHelper.
-
             if (sigHelper == null)
             {
                 throw new ArgumentNullException(nameof(sigHelper));
             }
 
-            int sigLength;
-            byte[] sigBytes;
-
             // get the signature in byte form
-            sigBytes = sigHelper.InternalGetSignature(out sigLength);
-            return new SignatureToken(TypeBuilder.GetTokenFromSig(GetNativeHandle(), sigBytes, sigLength), this);
+            byte[] sigBytes = sigHelper.InternalGetSignature(out int sigLength);
+            return new SignatureToken(TypeBuilder.GetTokenFromSig(GetNativeHandle(), sigBytes, sigLength));
         }
+
         public SignatureToken GetSignatureToken(byte[] sigBytes, int sigLength)
         {
             if (sigBytes == null)
+            {
                 throw new ArgumentNullException(nameof(sigBytes));
+            }
 
             byte[] localSigBytes = new byte[sigBytes.Length];
             Buffer.BlockCopy(sigBytes, 0, localSigBytes, 0, sigBytes.Length);
 
-            return new SignatureToken(TypeBuilder.GetTokenFromSig(GetNativeHandle(), localSigBytes, sigLength), this);
+            return new SignatureToken(TypeBuilder.GetTokenFromSig(GetNativeHandle(), localSigBytes, sigLength));
         }
 
         #endregion
@@ -1606,14 +1513,18 @@ namespace System.Reflection.Emit
         public void SetCustomAttribute(ConstructorInfo con, byte[] binaryAttribute)
         {
             if (con == null)
+            {
                 throw new ArgumentNullException(nameof(con));
+            }
             if (binaryAttribute == null)
+            {
                 throw new ArgumentNullException(nameof(binaryAttribute));
+            }
 
             TypeBuilder.DefineCustomAttribute(
                 this,
                 1,                                          // This is hard coding the module token to 1
-                this.GetConstructorToken(con).Token,
+                GetConstructorToken(con).Token,
                 binaryAttribute,
                 false, false);
         }
@@ -1653,20 +1564,15 @@ namespace System.Reflection.Emit
         // writer access can cause AVs and other problems.  The writer APIs should not be callable
         // directly by partial-trust code, but if they could this would be a security hole.  
         // Regardless, this is a reliability bug.  
-        // 
-        // For these reasons, we should consider making this API internal in Arrowhead
-        // (as it is in Silverlight), and consider validating that we're within a call
-        // to TypeBuilder.CreateType whenever this is used.
-        internal ISymbolWriter GetSymWriter()
-        {
-            return m_iSymWriter;
-        }
+        internal ISymbolWriter GetSymWriter() => _iSymWriter;
 
         public ISymbolDocumentWriter DefineDocument(string url, Guid language, Guid languageVendor, Guid documentType)
         {
             // url cannot be null but can be an empty string 
             if (url == null)
+            {
                 throw new ArgumentNullException(nameof(url));
+            }
 
             lock (SyncRoot)
             {
@@ -1676,19 +1582,16 @@ namespace System.Reflection.Emit
 
         private ISymbolDocumentWriter DefineDocumentNoLock(string url, Guid language, Guid languageVendor, Guid documentType)
         {
-            if (m_iSymWriter == null)
+            if (_iSymWriter == null)
             {
                 // Cannot DefineDocument when it is not a debug module
                 throw new InvalidOperationException(SR.InvalidOperation_NotADebugModule);
             }
 
-            return m_iSymWriter.DefineDocument(url, language, languageVendor, documentType);
+            return _iSymWriter.DefineDocument(url, language, languageVendor, documentType);
         }
 
-        public bool IsTransient()
-        {
-            return InternalModule.IsTransientInternal();
-        }
+        public bool IsTransient() => InternalModule.IsTransientInternal();
 
         #endregion
 
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilderData.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilderData.cs
index 066bb24e6f..02e945b261 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilderData.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilderData.cs
@@ -2,13 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Diagnostics;
-using System.Globalization;
-using System.IO;
-using System.Reflection;
-using System.Runtime.Versioning;
-
 namespace System.Reflection.Emit
 {
     // This is a package private class. This class hold all of the managed
@@ -16,47 +9,16 @@ namespace System.Reflection.Emit
     // this class cannot be accessed from the EE.
     internal class ModuleBuilderData
     {
-        internal ModuleBuilderData(ModuleBuilder module, string strModuleName, string strFileName, int tkFile)
-        {
-            m_globalTypeBuilder = new TypeBuilder(module);
-            m_module = module;
-            m_tkFile = tkFile;
+        public const string MultiByteValueClass = "$ArrayType$";
 
-            InitNames(strModuleName, strFileName);
-        }
+        public readonly TypeBuilder _globalTypeBuilder;
+        public readonly string _moduleName;
+        public bool _hasGlobalBeenCreated;
 
-        // Initialize module and file names.
-        private void InitNames(string strModuleName, string strFileName)
+        internal ModuleBuilderData(ModuleBuilder module, string moduleName)
         {
-            m_strModuleName = strModuleName;
-            if (strFileName == null)
-            {
-                // fake a transient module file name
-                m_strFileName = strModuleName;
-            }
-            else
-            {
-                string strExtension = Path.GetExtension(strFileName);
-                if (strExtension == null || strExtension == string.Empty)
-                {
-                    // This is required by our loader. It cannot load module file that does not have file extension.
-                    throw new ArgumentException(SR.Format(SR.Argument_NoModuleFileExtension, strFileName));
-                }
-                m_strFileName = strFileName;
-            }
+            _globalTypeBuilder = new TypeBuilder(module);
+            _moduleName = moduleName;
         }
-
-        internal string m_strModuleName;     // scope name (can be different from file name)
-        internal string m_strFileName;
-        internal bool m_fGlobalBeenCreated;
-        internal bool m_fHasGlobal;
-        internal TypeBuilder m_globalTypeBuilder;
-        internal ModuleBuilder m_module;
-
-        private int m_tkFile;
-        internal bool m_isSaved;
-        internal const string MULTI_BYTE_VALUE_CLASS = "$ArrayType$";
-        internal string m_strResourceFileName;
-        internal byte[] m_resourceBytes;
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterBuilder.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterBuilder.cs
index 2b0e18f4f8..d81fe7092c 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterBuilder.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterBuilder.cs
@@ -2,21 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** ParameterBuilder is used to create/associate parameter information
-**
-** 
-===========================================================*/
-
-using System.Runtime.InteropServices;
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
     public class ParameterBuilder
@@ -25,25 +10,28 @@ namespace System.Reflection.Emit
         public virtual void SetConstant(object defaultValue)
         {
             TypeBuilder.SetConstantValue(
-                m_methodBuilder.GetModuleBuilder(),
-                m_pdToken.Token,
-                m_iPosition == 0 ? m_methodBuilder.ReturnType : m_methodBuilder.m_parameterTypes[m_iPosition - 1],
+                _methodBuilder.GetModuleBuilder(),
+                _token.Token,
+                _position == 0 ? _methodBuilder.ReturnType : _methodBuilder.m_parameterTypes[_position - 1],
                 defaultValue);
         }
 
         // Use this function if client decides to form the custom attribute blob themselves
-
         public void SetCustomAttribute(ConstructorInfo con, byte[] binaryAttribute)
         {
             if (con == null)
+            {
                 throw new ArgumentNullException(nameof(con));
+            }
             if (binaryAttribute == null)
+            {
                 throw new ArgumentNullException(nameof(binaryAttribute));
+            }
 
             TypeBuilder.DefineCustomAttribute(
-                m_methodBuilder.GetModuleBuilder(),
-                m_pdToken.Token,
-                ((ModuleBuilder)m_methodBuilder.GetModule()).GetConstructorToken(con).Token,
+                _methodBuilder.GetModuleBuilder(),
+                _token.Token,
+                ((ModuleBuilder)_methodBuilder.GetModule()).GetConstructorToken(con).Token,
                 binaryAttribute,
                 false, false);
         }
@@ -55,65 +43,48 @@ namespace System.Reflection.Emit
             {
                 throw new ArgumentNullException(nameof(customBuilder));
             }
-            customBuilder.CreateCustomAttribute((ModuleBuilder)(m_methodBuilder.GetModule()), m_pdToken.Token);
+            customBuilder.CreateCustomAttribute((ModuleBuilder)(_methodBuilder.GetModule()), _token.Token);
         }
 
         internal ParameterBuilder(
             MethodBuilder methodBuilder,
             int sequence,
             ParameterAttributes attributes,
-            string strParamName)            // can be NULL string
+            string paramName)            // can be NULL string
         {
-            m_iPosition = sequence;
-            m_strParamName = strParamName;
-            m_methodBuilder = methodBuilder;
-            m_strParamName = strParamName;
-            m_attributes = attributes;
-            m_pdToken = new ParameterToken(TypeBuilder.SetParamInfo(
-                        m_methodBuilder.GetModuleBuilder().GetNativeHandle(),
-                        m_methodBuilder.GetToken().Token,
+            _position = sequence;
+            _name = paramName;
+            _methodBuilder = methodBuilder;
+            _attributes = attributes;
+            _token = new ParameterToken(TypeBuilder.SetParamInfo(
+                        _methodBuilder.GetModuleBuilder().GetNativeHandle(),
+                        _methodBuilder.GetToken().Token,
                         sequence,
                         attributes,
-                        strParamName));
+                        paramName));
         }
 
         public virtual ParameterToken GetToken()
         {
-            return m_pdToken;
+            return _token;
         }
 
-        public virtual string Name
-        {
-            get { return m_strParamName; }
-        }
+        public virtual string Name => _name;
 
-        public virtual int Position
-        {
-            get { return m_iPosition; }
-        }
+        public virtual int Position => _position;
 
-        public virtual int Attributes
-        {
-            get { return (int)m_attributes; }
-        }
+        public virtual int Attributes => (int)_attributes;
 
-        public bool IsIn
-        {
-            get { return ((m_attributes & ParameterAttributes.In) != 0); }
-        }
-        public bool IsOut
-        {
-            get { return ((m_attributes & ParameterAttributes.Out) != 0); }
-        }
-        public bool IsOptional
-        {
-            get { return ((m_attributes & ParameterAttributes.Optional) != 0); }
-        }
+        public bool IsIn => (_attributes & ParameterAttributes.In) != 0;
+
+        public bool IsOut => (_attributes & ParameterAttributes.Out) != 0;
+
+        public bool IsOptional => (_attributes & ParameterAttributes.Optional) != 0;
 
-        private string m_strParamName;
-        private int m_iPosition;
-        private ParameterAttributes m_attributes;
-        private MethodBuilder m_methodBuilder;
-        private ParameterToken m_pdToken;
+        private readonly string _name;
+        private readonly int _position;
+        private readonly ParameterAttributes _attributes;
+        private MethodBuilder _methodBuilder;
+        private ParameterToken _token;
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterToken.cs
index edb3514609..7eb917ddd6 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/ParameterToken.cs
@@ -2,66 +2,33 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Purpose: metadata tokens for a parameter
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
-{
-    // The ParameterToken class is an opaque representation of the Token returned
-    // by the Metadata to represent the parameter. 
+{  
+    /// <summary>
+    /// The ParameterToken class is an opaque representation of the Token returned
+    /// by the Metadata to represent the parameter.
+    /// </summary>
     public struct ParameterToken
     {
         public static readonly ParameterToken Empty = new ParameterToken();
-        internal int m_tkParameter;
 
+        private readonly int _token;
 
-        internal ParameterToken(int tkParam)
+        internal ParameterToken(int parameterToken)
         {
-            m_tkParameter = tkParam;
+            _token = parameterToken;
         }
 
-        public int Token
-        {
-            get { return m_tkParameter; }
-        }
+        public int Token => _token;
 
-        public override int GetHashCode()
-        {
-            return m_tkParameter;
-        }
+        public override int GetHashCode() => Token;
 
-        public override bool Equals(object obj)
-        {
-            if (obj is ParameterToken)
-                return Equals((ParameterToken)obj);
-            else
-                return false;
-        }
+        public override bool Equals(object obj) => obj is ParameterToken pt && Equals(pt);
 
-        public bool Equals(ParameterToken obj)
-        {
-            return obj.m_tkParameter == m_tkParameter;
-        }
+        public bool Equals(ParameterToken obj) => obj.Token == Token;
 
-        public static bool operator ==(ParameterToken a, ParameterToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(ParameterToken a, ParameterToken b) => a.Equals(b);
 
-        public static bool operator !=(ParameterToken a, ParameterToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(ParameterToken a, ParameterToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/PropertyToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/PropertyToken.cs
index 25b92244cc..fe8d316fd7 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/PropertyToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/PropertyToken.cs
@@ -2,66 +2,29 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Propertybuilder is for client to define properties for a class
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
     public struct PropertyToken
     {
         public static readonly PropertyToken Empty = new PropertyToken();
 
-        internal int m_property;
+        private readonly int _token;
 
-        internal PropertyToken(int str)
+        internal PropertyToken(int propertyToken)
         {
-            m_property = str;
+            _token = propertyToken;
         }
 
-        public int Token
-        {
-            get { return m_property; }
-        }
+        public int Token => _token;
 
-        // Satisfy value class requirements
-        public override int GetHashCode()
-        {
-            return m_property;
-        }
+        public override int GetHashCode() => Token;
 
-        // Satisfy value class requirements
-        public override bool Equals(object obj)
-        {
-            if (obj is PropertyToken)
-                return Equals((PropertyToken)obj);
-            else
-                return false;
-        }
+        public override bool Equals(object obj) => obj is PropertyToken pt && Equals(pt);
 
-        public bool Equals(PropertyToken obj)
-        {
-            return obj.m_property == m_property;
-        }
+        public bool Equals(PropertyToken obj) => obj.Token == Token;
 
-        public static bool operator ==(PropertyToken a, PropertyToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(PropertyToken a, PropertyToken b) => a.Equals(b);
 
-        public static bool operator !=(PropertyToken a, PropertyToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(PropertyToken a, PropertyToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/SignatureToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/SignatureToken.cs
index 780c61e314..ff61061b80 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/SignatureToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/SignatureToken.cs
@@ -2,67 +2,29 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** Signature:  SignatureToken
-** 
-** 
-**
-**
-** Purpose: Represents a Signature to the ILGenerator signature.
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-
 namespace System.Reflection.Emit
 {
     public struct SignatureToken
     {
         public static readonly SignatureToken Empty = new SignatureToken();
 
-        internal int m_signature;
-        internal ModuleBuilder m_moduleBuilder;
+        private int _token;
 
-        internal SignatureToken(int str, ModuleBuilder mod)
+        internal SignatureToken(int signatureToken)
         {
-            m_signature = str;
-            m_moduleBuilder = mod;
+            _token = signatureToken;
         }
 
-        public int Token
-        {
-            get { return m_signature; }
-        }
+        public int Token => _token;
 
-        public override int GetHashCode()
-        {
-            return m_signature;
-        }
+        public override int GetHashCode() => Token;
 
-        public override bool Equals(object obj)
-        {
-            if (obj is SignatureToken)
-                return Equals((SignatureToken)obj);
-            else
-                return false;
-        }
+        public override bool Equals(object obj) => obj is SignatureToken st && Equals(st);
 
-        public bool Equals(SignatureToken obj)
-        {
-            return obj.m_signature == m_signature;
-        }
+        public bool Equals(SignatureToken obj) => obj.Token == Token;
 
-        public static bool operator ==(SignatureToken a, SignatureToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(SignatureToken a, SignatureToken b) => a.Equals(b);
 
-        public static bool operator !=(SignatureToken a, SignatureToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(SignatureToken a, SignatureToken b) => !(a == b);
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilder.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilder.cs
index 30978730ff..16a64d9252 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilder.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilder.cs
@@ -507,7 +507,7 @@ namespace System.Reflection.Emit
             AssemblyBuilder containingAssem = m_module.ContainingAssemblyBuilder;
 
             // cannot have two types within the same assembly of the same name
-            containingAssem.m_assemblyData.CheckTypeNameConflict(fullname, enclosingType);
+            containingAssem._assemblyData.CheckTypeNameConflict(fullname, enclosingType);
 
             if (enclosingType != null)
             {
@@ -602,7 +602,7 @@ namespace System.Reflection.Emit
             ThrowIfCreated();
 
             // form the value class name
-            strValueClassName = ModuleBuilderData.MULTI_BYTE_VALUE_CLASS + size.ToString();
+            strValueClassName = ModuleBuilderData.MultiByteValueClass + size.ToString();
 
             // Is this already defined in this module?
             Type temp = m_module.FindTypeBuilderWithName(strValueClassName, false);
@@ -2123,7 +2123,7 @@ namespace System.Reflection.Emit
                     exceptions, (exceptions != null) ? exceptions.Length : 0,
                     tokenFixups, (tokenFixups != null) ? tokenFixups.Length : 0);
 
-                if (m_module.ContainingAssemblyBuilder.m_assemblyData.m_access == AssemblyBuilderAccess.Run)
+                if (m_module.ContainingAssemblyBuilder._assemblyData._access == AssemblyBuilderAccess.Run)
                 {
                     // if we don't need the data structures to build the method any more
                     // throw them away.
diff --git a/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeToken.cs b/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeToken.cs
index 4825a04f24..ecb243273c 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeToken.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/Emit/TypeToken.cs
@@ -2,67 +2,30 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-/*============================================================
-**
-** 
-** 
-**
-**
-** Purpose: Represents a Class to the ILGenerator class.
-**
-** 
-===========================================================*/
-
-using System;
-using System.Reflection;
-using System.Threading;
-
 namespace System.Reflection.Emit
 {
     public struct TypeToken
     {
         public static readonly TypeToken Empty = new TypeToken();
 
-        internal int m_class;
+        private readonly int _token;
 
-
-        internal TypeToken(int str)
+        internal TypeToken(int typeToken)
         {
-            m_class = str;
+            _token = typeToken;
         }
 
-        public int Token
-        {
-            get { return m_class; }
-        }
+        public int Token => _token;
 
-        public override int GetHashCode()
-        {
-            return m_class;
-        }
+        public override int GetHashCode() => Token;
 
-        public override bool Equals(object obj)
-        {
-            if (obj is TypeToken)
-                return Equals((TypeToken)obj);
-            else
-                return false;
-        }
+        public override bool Equals(object obj) => obj is TypeToken tt && Equals(tt);
 
-        public bool Equals(TypeToken obj)
-        {
-            return obj.m_class == m_class;
-        }
+        public bool Equals(TypeToken obj) => obj.Token == Token;
 
-        public static bool operator ==(TypeToken a, TypeToken b)
-        {
-            return a.Equals(b);
-        }
+        public static bool operator ==(TypeToken a, TypeToken b) => a.Equals(b);
 
-        public static bool operator !=(TypeToken a, TypeToken b)
-        {
-            return !(a == b);
-        }
+        public static bool operator !=(TypeToken a, TypeToken b) => !(a == b);
     }
 }
 
diff --git a/src/System.Private.CoreLib/src/System/Reflection/RuntimeAssembly.cs b/src/System.Private.CoreLib/src/System/Reflection/RuntimeAssembly.cs
index f885c15636..deac03b3b5 100644
--- a/src/System.Private.CoreLib/src/System/Reflection/RuntimeAssembly.cs
+++ b/src/System.Private.CoreLib/src/System/Reflection/RuntimeAssembly.cs
@@ -67,19 +67,9 @@ namespace System.Reflection
             return codeBase;
         }
 
-        public override string CodeBase
-        {
-            get
-            {
-                string codeBase = GetCodeBase(false);
-                return codeBase;
-            }
-        }
+        public override string CodeBase => GetCodeBase(false);
 
-        internal RuntimeAssembly GetNativeHandle()
-        {
-            return this;
-        }
+        internal RuntimeAssembly GetNativeHandle() => this;
 
         // If the assembly is copied before it is loaded, the codebase will be set to the
         // actual file loaded if copiedName is true. If it is false, then the original code base
@@ -101,15 +91,12 @@ namespace System.Reflection
                     GetFlags() | AssemblyNameFlags.PublicKey,
                     null); // strong name key pair
 
-            PortableExecutableKinds pek;
-            ImageFileMachine ifm;
-
             Module manifestModule = ManifestModule;
             if (manifestModule != null)
             {
                 if (manifestModule.MDStreamVersion > 0x10000)
                 {
-                    ManifestModule.GetPEKind(out pek, out ifm);
+                    ManifestModule.GetPEKind(out PortableExecutableKinds pek, out ImageFileMachine ifm);
                     an.SetProcArchIndex(pek, ifm);
                 }
             }
diff --git a/src/vm/assembly.cpp b/src/vm/assembly.cpp
index 02781aa110..a7315b3b5a 100644
--- a/src/vm/assembly.cpp
+++ b/src/vm/assembly.cpp
@@ -145,7 +145,7 @@ Assembly::Assembly(BaseDomain *pDomain, PEAssembly* pFile, DebuggerAssemblyContr
     STANDARD_VM_CONTRACT;
 }
 
-// This name needs to stay in sync with AssemblyBuilder.MANIFEST_MODULE_NAME
+// This name needs to stay in sync with AssemblyBuilder.ManifestModuleName
 // which is used in AssemblyBuilder.InitManifestModule
 #define REFEMIT_MANIFEST_MODULE_NAME W("RefEmit_InMemoryManifestModule")