Delete IsNonW8PFrameworkAPI checks (#9964)

Dead code in CoreCLR

22 files changed, 35 insertions, 581 deletions

diff --git a/src/inc/appxutil.h b/src/inc/appxutil.h
index 893c429c95..312c486332 100644
--- a/src/inc/appxutil.h
+++ b/src/inc/appxutil.h
@@ -33,12 +33,6 @@ namespace AppX
     // On CoreCLR, the host is in charge of determining whether the process is AppX or not.
     void SetIsAppXProcess(bool);
 
-    inline bool IsAppXNGen()
-    {
-        WRAPPER_NO_CONTRACT;
-        return false;
-    }
-
 #ifdef DACCESS_COMPILE
         bool DacIsAppXProcess();
 #endif // DACCESS_COMPILE
diff --git a/src/inc/clrconfigvalues.h b/src/inc/clrconfigvalues.h
index 6a30af16db..6160f2061a 100644
--- a/src/inc/clrconfigvalues.h
+++ b/src/inc/clrconfigvalues.h
@@ -156,9 +156,6 @@ RETAIL_CONFIG_DWORD_INFO(EXTERNAL_DateTime_NetFX40AmPmParseAdjustment, W("Enable
 #ifdef FEATURE_RANDOMIZED_STRING_HASHING
 RETAIL_CONFIG_DWORD_INFO(EXTERNAL_UseRandomizedStringHashAlgorithm, W("UseRandomizedStringHashAlgorithm"), 0, "Flag to use a string hashing algorithm who's behavior differs between AppDomains")
 #endif // FEATURE_RANDOMIZED_STRING_HASHING
-#ifdef FEATURE_APPX
-RETAIL_CONFIG_DWORD_INFO(INTERNAL_Windows8ProfileAPICheckFlag, W("Windows8ProfileAPICheckFlag"), 0, "Windows 8 Profile API check behavior (non-W8P framework APIs cannot be accessed through Reflection and RefEmit). 0: normal (only check in non-dev-mode APPX). 1: always check. 2: never check.");
-#endif
 
 // 
 // Conditional breakpoints
diff --git a/src/mscorlib/src/System/AppDomain.cs b/src/mscorlib/src/System/AppDomain.cs
index 9a3d70ad11..4db0c15fda 100644
--- a/src/mscorlib/src/System/AppDomain.cs
+++ b/src/mscorlib/src/System/AppDomain.cs
@@ -286,12 +286,8 @@ namespace System
 
             APPX_FLAGS_APPX_MODEL = 0x02,
             APPX_FLAGS_APPX_DESIGN_MODE = 0x04,
-            APPX_FLAGS_APPX_NGEN = 0x08,
             APPX_FLAGS_APPX_MASK = APPX_FLAGS_APPX_MODEL |
-                                            APPX_FLAGS_APPX_DESIGN_MODE |
-                                            APPX_FLAGS_APPX_NGEN,
-
-            APPX_FLAGS_API_CHECK = 0x10,
+                                            APPX_FLAGS_APPX_DESIGN_MODE,
         }
 
         private static APPX_FLAGS Flags
@@ -305,22 +301,6 @@ namespace System
                 return s_flags;
             }
         }
-
-        internal static bool ProfileAPICheck
-        {
-            get
-            {
-                return (Flags & APPX_FLAGS.APPX_FLAGS_API_CHECK) != 0;
-            }
-        }
-
-        internal static bool IsAppXNGen
-        {
-            get
-            {
-                return (Flags & APPX_FLAGS.APPX_FLAGS_APPX_NGEN) != 0;
-            }
-        }
 #endif // FEATURE_APPX
 
         [DllImport(JitHelpers.QCall, CharSet = CharSet.Unicode)]
diff --git a/src/mscorlib/src/System/Delegate.cs b/src/mscorlib/src/System/Delegate.cs
index bd7a1f21db..5f017733da 100644
--- a/src/mscorlib/src/System/Delegate.cs
+++ b/src/mscorlib/src/System/Delegate.cs
@@ -628,19 +628,6 @@ namespace System
         {
             Debug.Assert((flags & DelegateBindingFlags.SkipSecurityChecks) == 0);
 
-#if FEATURE_APPX
-            bool nonW8PMethod = (rtMethod.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0;
-            bool nonW8PType = (rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0;
-            if (nonW8PMethod || nonW8PType)
-            {
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(
-                        Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext",
-                                                      nonW8PMethod ? rtMethod.FullName : rtType.FullName));
-            }
-#endif
-
             return UnsafeCreateDelegate(rtType, rtMethod, firstArgument, flags);
         }
 
diff --git a/src/mscorlib/src/System/Globalization/CultureInfo.Windows.cs b/src/mscorlib/src/System/Globalization/CultureInfo.Windows.cs
index 941b9d66d3..a7f43f249a 100644
--- a/src/mscorlib/src/System/Globalization/CultureInfo.Windows.cs
+++ b/src/mscorlib/src/System/Globalization/CultureInfo.Windows.cs
@@ -235,17 +235,6 @@ namespace System.Globalization
                 return null;
             }
 
-            // If running within a compilation process (mscorsvw.exe, for example), it is illegal to
-            // load any non-mscorlib assembly for execution. Since WindowsRuntimeResourceManager lives
-            // in System.Runtime.WindowsRuntime, caller will need to fall back to default Win32 value,
-            // which should be fine because we should only ever need to access FX resources during NGEN.
-            // FX resources are always loaded from satellite assemblies - even in AppX processes (see the
-            // comments in code:System.Resources.ResourceManager.SetAppXConfiguration for more details).
-            if (AppDomain.IsAppXNGen)
-            {
-                return null;
-            }
-
             CultureInfo toReturn = null;
 
             try 
@@ -269,17 +258,6 @@ namespace System.Globalization
 
         internal static bool SetCultureInfoForUserPreferredLanguageInAppX(CultureInfo ci)
         {
-            // If running within a compilation process (mscorsvw.exe, for example), it is illegal to
-            // load any non-mscorlib assembly for execution. Since WindowsRuntimeResourceManager lives
-            // in System.Runtime.WindowsRuntime, caller will need to fall back to default Win32 value,
-            // which should be fine because we should only ever need to access FX resources during NGEN.
-            // FX resources are always loaded from satellite assemblies - even in AppX processes (see the
-            // comments in code:System.Resources.ResourceManager.SetAppXConfiguration for more details).
-            if (AppDomain.IsAppXNGen)
-            {
-                return false;
-            }
-
             if (s_WindowsRuntimeResourceManager == null)
             {
                 s_WindowsRuntimeResourceManager = ResourceManager.GetWinRTResourceManager();
diff --git a/src/mscorlib/src/System/Reflection/Assembly.cs b/src/mscorlib/src/System/Reflection/Assembly.cs
index 37698f6629..57ea5cabed 100644
--- a/src/mscorlib/src/System/Reflection/Assembly.cs
+++ b/src/mscorlib/src/System/Reflection/Assembly.cs
@@ -772,7 +772,6 @@ namespace System.Reflection
             ASSEMBLY_FLAGS_UNKNOWN = 0x00000000,
             ASSEMBLY_FLAGS_INITIALIZED = 0x01000000,
             ASSEMBLY_FLAGS_FRAMEWORK = 0x02000000,
-            ASSEMBLY_FLAGS_SAFE_REFLECTION = 0x04000000,
             ASSEMBLY_FLAGS_TOKEN_MASK = 0x00FFFFFF,
         }
 #endif // FEATURE_APPX
@@ -793,16 +792,6 @@ namespace System.Reflection
         #endregion
 
 #if FEATURE_APPX
-        internal int InvocableAttributeCtorToken
-        {
-            get
-            {
-                int token = (int)(Flags & ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_TOKEN_MASK);
-
-                return token | (int)MetadataTokenType.MethodDef;
-            }
-        }
-
         private ASSEMBLY_FLAGS Flags
         {
             get
@@ -810,7 +799,7 @@ namespace System.Reflection
                 if ((m_flags & ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_INITIALIZED) == 0)
                 {
                     ASSEMBLY_FLAGS flags = ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_UNKNOWN
-                        | ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_FRAMEWORK | ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_SAFE_REFLECTION;
+                        | ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_FRAMEWORK;
 
                     m_flags = flags | ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_INITIALIZED;
                 }
@@ -1211,14 +1200,6 @@ namespace System.Reflection
             ASSEMBLY_FLAGS flags = Flags;
             return (flags & ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_FRAMEWORK) != 0;
         }
-
-        // Returns true if we want to allow this assembly to invoke non-W8P
-        // framework APIs through reflection.
-        internal bool IsSafeForReflection()
-        {
-            ASSEMBLY_FLAGS flags = Flags;
-            return (flags & ASSEMBLY_FLAGS.ASSEMBLY_FLAGS_SAFE_REFLECTION) != 0;
-        }
 #endif
 
         [MethodImplAttribute(MethodImplOptions.InternalCall)]
diff --git a/src/mscorlib/src/System/Reflection/ConstructorInfo.cs b/src/mscorlib/src/System/Reflection/ConstructorInfo.cs
index 6249a6a1c9..284134a5c0 100644
--- a/src/mscorlib/src/System/Reflection/ConstructorInfo.cs
+++ b/src/mscorlib/src/System/Reflection/ConstructorInfo.cs
@@ -109,28 +109,6 @@ namespace System.Reflection
         private volatile Signature m_signature;
         private INVOCATION_FLAGS m_invocationFlags;
 
-#if FEATURE_APPX
-        private bool IsNonW8PFrameworkAPI()
-        {
-            if (DeclaringType.IsArray && IsPublic && !IsStatic)
-                return false;
-
-            RuntimeAssembly rtAssembly = GetRuntimeAssembly();
-            if (rtAssembly.IsFrameworkAssembly())
-            {
-                int ctorToken = rtAssembly.InvocableAttributeCtorToken;
-                if (System.Reflection.MetadataToken.IsNullToken(ctorToken) ||
-                    !CustomAttribute.IsAttributeDefined(GetRuntimeModule(), MetadataToken, ctorToken))
-                    return true;
-            }
-
-            if (GetRuntimeType().IsNonW8PFrameworkAPI())
-                return true;
-
-            return false;
-        }
-#endif // FEATURE_APPX
-
         internal INVOCATION_FLAGS InvocationFlags
         {
             get
@@ -174,11 +152,6 @@ namespace System.Reflection
                             invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_IS_DELEGATE_CTOR;
                     }
 
-#if FEATURE_APPX
-                    if (AppDomain.ProfileAPICheck && IsNonW8PFrameworkAPI())
-                        invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API;
-#endif // FEATURE_APPX
-
                     m_invocationFlags = invocationFlags | INVOCATION_FLAGS.INVOCATION_FLAGS_INITIALIZED;
                 }
 
@@ -469,16 +442,6 @@ namespace System.Reflection
             // check basic method consistency. This call will throw if there are problems in the target/method relationship
             CheckConsistency(obj);
 
-#if FEATURE_APPX
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", FullName));
-            }
-#endif
-
             if (obj != null)
             {
                 // For unverifiable code, we require the caller to be critical.
@@ -553,16 +516,6 @@ namespace System.Reflection
             if ((invocationFlags & (INVOCATION_FLAGS.INVOCATION_FLAGS_NO_INVOKE | INVOCATION_FLAGS.INVOCATION_FLAGS_CONTAINS_STACK_POINTERS | INVOCATION_FLAGS.INVOCATION_FLAGS_NO_CTOR_INVOKE)) != 0)
                 ThrowNoInvokeException();
 
-#if FEATURE_APPX
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", FullName));
-            }
-#endif
-
             // get the signature
             Signature sig = Signature;
 
diff --git a/src/mscorlib/src/System/Reflection/Emit/AssemblyBuilder.cs b/src/mscorlib/src/System/Reflection/Emit/AssemblyBuilder.cs
index ca273d65d1..2ff87a02ac 100644
--- a/src/mscorlib/src/System/Reflection/Emit/AssemblyBuilder.cs
+++ b/src/mscorlib/src/System/Reflection/Emit/AssemblyBuilder.cs
@@ -177,10 +177,6 @@ namespace System.Reflection.Emit
         private bool m_fManifestModuleUsedAsDefinedModule;
         internal const string MANIFEST_MODULE_NAME = "RefEmit_InMemoryManifestModule";
 
-#if FEATURE_APPX
-        private bool m_profileAPICheck;
-#endif
-
         internal ModuleBuilder GetModuleBuilder(InternalModuleBuilder module)
         {
             Contract.Requires(module != null);
@@ -216,16 +212,6 @@ namespace System.Reflection.Emit
         {
             return InternalAssembly.GetNativeHandle();
         }
-
-#if FEATURE_APPX
-        internal bool ProfileAPICheck
-        {
-            get
-            {
-                return m_profileAPICheck;
-            }
-        }
-#endif
         #endregion
 
         #region Constructor
@@ -301,14 +287,7 @@ namespace System.Reflection.Emit
                                                      name.Name,
                                                      access,
                                                      dir);
-#if FEATURE_APPX
-            if (AppDomain.ProfileAPICheck)
-            {
-                RuntimeAssembly creator = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (creator != null && !creator.IsFrameworkAssembly())
-                    m_profileAPICheck = true;
-            }
-#endif
+
             // Make sure that ManifestModule is properly initialized
             // We need to do this before setting any CustomAttribute
             InitManifestModule();
diff --git a/src/mscorlib/src/System/Reflection/Emit/DynamicILGenerator.cs b/src/mscorlib/src/System/Reflection/Emit/DynamicILGenerator.cs
index f0a5945034..ec725acad7 100644
--- a/src/mscorlib/src/System/Reflection/Emit/DynamicILGenerator.cs
+++ b/src/mscorlib/src/System/Reflection/Emit/DynamicILGenerator.cs
@@ -42,16 +42,6 @@ namespace System.Reflection.Emit
                                           new DynamicResolver(this));
         }
 
-#if FEATURE_APPX
-        private bool ProfileAPICheck
-        {
-            get
-            {
-                return ((DynamicMethod)m_methodBuilder).ProfileAPICheck;
-            }
-        }
-#endif // FEATURE_APPX
-
         // *** ILGenerator api ***
 
         public override LocalBuilder DeclareLocal(Type localType, bool pinned)
@@ -66,11 +56,6 @@ namespace System.Reflection.Emit
             if (rtType == null)
                 throw new ArgumentException(Environment.GetResourceString("Argument_MustBeRuntimeType"));
 
-#if FEATURE_APPX
-            if (ProfileAPICheck && (rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-#endif
-
             localBuilder = new LocalBuilder(m_localCount, localType, m_methodBuilder);
             // add the localType to local signature
             m_localSignature.AddArgument(localType, pinned);
@@ -496,94 +481,36 @@ namespace System.Reflection.Emit
         #region GetTokenFor helpers
         private int GetTokenFor(RuntimeType rtType)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck && (rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-#endif
-
             return m_scope.GetTokenFor(rtType.TypeHandle);
         }
 
         private int GetTokenFor(RuntimeFieldInfo runtimeField)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck)
-            {
-                RtFieldInfo rtField = runtimeField as RtFieldInfo;
-                if (rtField != null && (rtField.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtField.FullName));
-            }
-#endif
-
             return m_scope.GetTokenFor(runtimeField.FieldHandle);
         }
 
         private int GetTokenFor(RuntimeFieldInfo runtimeField, RuntimeType rtType)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck)
-            {
-                RtFieldInfo rtField = runtimeField as RtFieldInfo;
-                if (rtField != null && (rtField.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtField.FullName));
-
-                if ((rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-            }
-#endif
-
             return m_scope.GetTokenFor(runtimeField.FieldHandle, rtType.TypeHandle);
         }
 
         private int GetTokenFor(RuntimeConstructorInfo rtMeth)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck && (rtMeth.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtMeth.FullName));
-#endif
-
             return m_scope.GetTokenFor(rtMeth.MethodHandle);
         }
 
         private int GetTokenFor(RuntimeConstructorInfo rtMeth, RuntimeType rtType)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck)
-            {
-                if ((rtMeth.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtMeth.FullName));
-
-                if ((rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-            }
-#endif
-
             return m_scope.GetTokenFor(rtMeth.MethodHandle, rtType.TypeHandle);
         }
 
         private int GetTokenFor(RuntimeMethodInfo rtMeth)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck && (rtMeth.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtMeth.FullName));
-#endif
-
             return m_scope.GetTokenFor(rtMeth.MethodHandle);
         }
 
         private int GetTokenFor(RuntimeMethodInfo rtMeth, RuntimeType rtType)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck)
-            {
-                if ((rtMeth.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtMeth.FullName));
-
-                if ((rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-            }
-#endif
-
             return m_scope.GetTokenFor(rtMeth.MethodHandle, rtType.TypeHandle);
         }
 
@@ -594,10 +521,6 @@ namespace System.Reflection.Emit
 
         private int GetTokenForVarArgMethod(RuntimeMethodInfo rtMeth, SignatureHelper sig)
         {
-#if FEATURE_APPX
-            if (ProfileAPICheck && (rtMeth.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtMeth.FullName));
-#endif
             VarArgMethod varArgMeth = new VarArgMethod(rtMeth, sig);
             return m_scope.GetTokenFor(varArgMeth);
         }
diff --git a/src/mscorlib/src/System/Reflection/Emit/DynamicMethod.cs b/src/mscorlib/src/System/Reflection/Emit/DynamicMethod.cs
index 9aae25c715..540a5b73dc 100644
--- a/src/mscorlib/src/System/Reflection/Emit/DynamicMethod.cs
+++ b/src/mscorlib/src/System/Reflection/Emit/DynamicMethod.cs
@@ -42,13 +42,6 @@ namespace System.Reflection.Emit
         // assigned by the DynamicResolver ctor
         internal DynamicResolver m_resolver;
 
-        // Always false unless we are in an immersive (non dev mode) process.
-#if FEATURE_APPX
-        private bool m_profileAPICheck;
-
-        private RuntimeAssembly m_creatorAssembly;
-#endif
-
         internal bool m_restrictedSkipVisibility;
         // The context when the method was created. We use this to do the RestrictedMemberAccess checks.
         // These checks are done when the method is compiled. This can happen at an arbitrary time,
@@ -65,13 +58,10 @@ namespace System.Reflection.Emit
 
         private DynamicMethod() { }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -80,18 +70,14 @@ namespace System.Reflection.Emit
                 null,   // owner
                 null,   // m
                 false,  // skipVisibility
-                true,
-                ref stackMark);  // transparentMethod
+                true);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes,
                              bool restrictedSkipVisibility)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -100,18 +86,17 @@ namespace System.Reflection.Emit
                 null,   // owner
                 null,   // m
                 restrictedSkipVisibility,
-                true,
-                ref stackMark);  // transparentMethod
+                true);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes,
                              Module m)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(m, ref stackMark, false);
+            if (m == null)
+                throw new ArgumentNullException(nameof(m));
+
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -120,19 +105,18 @@ namespace System.Reflection.Emit
                 null,   // owner
                 m,      // m
                 false,  // skipVisibility
-                false,
-                ref stackMark);  // transparentMethod
+                false);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes,
                              Module m,
                              bool skipVisibility)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(m, ref stackMark, skipVisibility);
+            if (m == null)
+                throw new ArgumentNullException(nameof(m));
+
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -141,11 +125,9 @@ namespace System.Reflection.Emit
                 null,   // owner
                 m,      // m
                 skipVisibility,
-                false,
-                ref stackMark); // transparentMethod
+                false);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              MethodAttributes attributes,
                              CallingConventions callingConvention,
@@ -154,8 +136,9 @@ namespace System.Reflection.Emit
                              Module m,
                              bool skipVisibility)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(m, ref stackMark, skipVisibility);
+            if (m == null)
+                throw new ArgumentNullException(nameof(m));
+
             Init(name,
                 attributes,
                 callingConvention,
@@ -164,18 +147,17 @@ namespace System.Reflection.Emit
                 null,   // owner
                 m,      // m
                 skipVisibility,
-                false,
-                ref stackMark); // transparentMethod
+                false);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes,
                              Type owner)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(owner, ref stackMark, false);
+            if (owner == null)
+                throw new ArgumentNullException(nameof(owner));
+
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -184,19 +166,18 @@ namespace System.Reflection.Emit
                 owner,  // owner
                 null,   // m
                 false,  // skipVisibility
-                false,
-                ref stackMark); // transparentMethod
+                false);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              Type returnType,
                              Type[] parameterTypes,
                              Type owner,
                              bool skipVisibility)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(owner, ref stackMark, skipVisibility);
+            if (owner == null)
+                throw new ArgumentNullException(nameof(owner));
+
             Init(name,
                 MethodAttributes.Public | MethodAttributes.Static,
                 CallingConventions.Standard,
@@ -205,11 +186,9 @@ namespace System.Reflection.Emit
                 owner,  // owner
                 null,   // m
                 skipVisibility,
-                false,
-                ref stackMark); // transparentMethod
+                false);
         }
 
-        [System.Security.DynamicSecurityMethod] // Methods containing StackCrawlMark local var has to be marked DynamicSecurityMethod
         public DynamicMethod(string name,
                              MethodAttributes attributes,
                              CallingConventions callingConvention,
@@ -218,8 +197,9 @@ namespace System.Reflection.Emit
                              Type owner,
                              bool skipVisibility)
         {
-            StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-            PerformSecurityCheck(owner, ref stackMark, skipVisibility);
+            if (owner == null)
+                throw new ArgumentNullException(nameof(owner));
+
             Init(name,
                 attributes,
                 callingConvention,
@@ -228,8 +208,7 @@ namespace System.Reflection.Emit
                 owner,  // owner
                 null,   // m
                 skipVisibility,
-                false,
-                ref stackMark); // transparentMethod
+                false);
         }
 
         // helpers for intialization
@@ -298,8 +277,7 @@ namespace System.Reflection.Emit
                                  Type owner,
                                  Module m,
                                  bool skipVisibility,
-                                 bool transparentMethod,
-                                 ref StackCrawlMark stackMark)
+                                 bool transparentMethod)
         {
             DynamicMethod.CheckConsistency(attributes, callingConvention);
 
@@ -337,7 +315,7 @@ namespace System.Reflection.Emit
             }
             else
             {
-                Debug.Assert(m != null || owner != null, "PerformSecurityCheck should ensure that either m or owner is set");
+                Debug.Assert(m != null || owner != null, "Constructor should ensure that either m or owner is set");
                 Debug.Assert(m == null || !m.Equals(s_anonymouslyHostedDynamicMethodsModule), "The user cannot explicitly use this assembly");
                 Debug.Assert(m == null || owner == null, "m and owner cannot both be set");
 
@@ -371,33 +349,9 @@ namespace System.Reflection.Emit
             if (name == null)
                 throw new ArgumentNullException(nameof(name));
 
-#if FEATURE_APPX
-            if (AppDomain.ProfileAPICheck)
-            {
-                if (m_creatorAssembly == null)
-                    m_creatorAssembly = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-
-                if (m_creatorAssembly != null && !m_creatorAssembly.IsFrameworkAssembly())
-                    m_profileAPICheck = true;
-            }
-#endif // FEATURE_APPX
-
             m_dynMethod = new RTDynamicMethod(this, name, attributes, callingConvention);
         }
 
-        private void PerformSecurityCheck(Module m, ref StackCrawlMark stackMark, bool skipVisibility)
-        {
-            if (m == null)
-                throw new ArgumentNullException(nameof(m));
-            Contract.EndContractBlock();
-        }
-
-        private void PerformSecurityCheck(Type owner, ref StackCrawlMark stackMark, bool skipVisibility)
-        {
-            if (owner == null)
-                throw new ArgumentNullException(nameof(owner));
-        }
-
         //
         // Delegate and method creation
         //
@@ -432,22 +386,6 @@ namespace System.Reflection.Emit
             return d;
         }
 
-#if FEATURE_APPX
-        internal bool ProfileAPICheck
-        {
-            get
-            {
-                return m_profileAPICheck;
-            }
-
-            [FriendAccessAllowed]
-            set
-            {
-                m_profileAPICheck = value;
-            }
-        }
-#endif
-
         // This is guaranteed to return a valid handle
         internal unsafe RuntimeMethodHandle GetMethodDescriptor()
         {
diff --git a/src/mscorlib/src/System/Reflection/Emit/ModuleBuilder.cs b/src/mscorlib/src/System/Reflection/Emit/ModuleBuilder.cs
index 2d1920338d..2dc9f51837 100644
--- a/src/mscorlib/src/System/Reflection/Emit/ModuleBuilder.cs
+++ b/src/mscorlib/src/System/Reflection/Emit/ModuleBuilder.cs
@@ -178,14 +178,6 @@ namespace System.Reflection.Emit
         {
             Debug.Assert(method != null);
 
-#if FEATURE_APPX
-            if (ContainingAssemblyBuilder.ProfileAPICheck)
-            {
-                if ((method.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", method.FullName));
-            }
-#endif
-
             return GetMemberRefOfMethodInfo(GetNativeHandle(), tr, method);
         }
 
@@ -193,14 +185,6 @@ namespace System.Reflection.Emit
         {
             Debug.Assert(method != null);
 
-#if FEATURE_APPX
-            if (ContainingAssemblyBuilder.ProfileAPICheck)
-            {
-                if ((method.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", method.FullName));
-            }
-#endif
-
             return GetMemberRefOfMethodInfo(GetNativeHandle(), tr, method);
         }
 
@@ -212,15 +196,6 @@ namespace System.Reflection.Emit
         {
             Debug.Assert(runtimeField != null);
 
-#if FEATURE_APPX
-            if (ContainingAssemblyBuilder.ProfileAPICheck)
-            {
-                RtFieldInfo rtField = runtimeField as RtFieldInfo;
-                if (rtField != null && (rtField.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtField.FullName));
-            }
-#endif
-
             return GetMemberRefOfFieldInfo(GetNativeHandle(), tkType, declaringType, runtimeField.MetadataToken);
         }
 
@@ -285,17 +260,6 @@ namespace System.Reflection.Emit
             Debug.Assert(!type.IsByRef, "Must not be ByRef.");
             Debug.Assert(!type.IsGenericType || type.IsGenericTypeDefinition, "Must not have generic arguments.");
 
-#if FEATURE_APPX
-            if (ContainingAssemblyBuilder.ProfileAPICheck)
-            {
-                RuntimeType rtType = type as RuntimeType;
-                if (rtType != null && (rtType.InvocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-                {
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", rtType.FullName));
-                }
-            }
-#endif
-
             return GetTypeRef(GetNativeHandle(), typeName, GetRuntimeModuleFromModule(refedModule).GetNativeHandle(), strRefedModuleFileName, tkResolution);
         }
 
diff --git a/src/mscorlib/src/System/Reflection/FieldInfo.cs b/src/mscorlib/src/System/Reflection/FieldInfo.cs
index 3ff0f7d204..511fef5202 100644
--- a/src/mscorlib/src/System/Reflection/FieldInfo.cs
+++ b/src/mscorlib/src/System/Reflection/FieldInfo.cs
@@ -323,29 +323,6 @@ namespace System.Reflection
         private RuntimeType m_fieldType;
         private INVOCATION_FLAGS m_invocationFlags;
 
-#if FEATURE_APPX
-        private bool IsNonW8PFrameworkAPI()
-        {
-            if (GetRuntimeType().IsNonW8PFrameworkAPI())
-                return true;
-
-            // Allow "value__"
-            if (m_declaringType.IsEnum)
-                return false;
-
-            RuntimeAssembly rtAssembly = GetRuntimeAssembly();
-            if (rtAssembly.IsFrameworkAssembly())
-            {
-                int ctorToken = rtAssembly.InvocableAttributeCtorToken;
-                if (System.Reflection.MetadataToken.IsNullToken(ctorToken) ||
-                    !CustomAttribute.IsAttributeDefined(GetRuntimeModule(), MetadataToken, ctorToken))
-                    return true;
-            }
-
-            return false;
-        }
-#endif
-
         internal INVOCATION_FLAGS InvocationFlags
         {
             get
@@ -390,11 +367,6 @@ namespace System.Reflection
                             invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_FIELD_SPECIAL_CAST;
                     }
 
-#if FEATURE_APPX
-                    if (AppDomain.ProfileAPICheck && IsNonW8PFrameworkAPI())
-                        invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API;
-#endif // FEATURE_APPX
-
                     // must be last to avoid threading problems
                     m_invocationFlags = invocationFlags | INVOCATION_FLAGS.INVOCATION_FLAGS_INITIALIZED;
                 }
@@ -483,15 +455,6 @@ namespace System.Reflection
             value = fieldType.CheckValue(value, binder, culture, invokeAttr);
 
             #region Security Check
-#if FEATURE_APPX
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", FullName));
-            }
-#endif
-
             if ((invocationFlags & (INVOCATION_FLAGS.INVOCATION_FLAGS_SPECIAL_FIELD | INVOCATION_FLAGS.INVOCATION_FLAGS_NEED_SECURITY)) != 0)
                 PerformVisibilityCheckOnField(m_fieldHandle, obj, m_declaringType, m_fieldAttributes, (uint)m_invocationFlags);
             #endregion
@@ -556,15 +519,6 @@ namespace System.Reflection
 
             CheckConsistency(obj);
 
-#if FEATURE_APPX
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", FullName));
-            }
-#endif
-
             RuntimeType fieldType = (RuntimeType)FieldType;
             if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NEED_SECURITY) != 0)
                 PerformVisibilityCheckOnField(m_fieldHandle, obj, m_declaringType, m_fieldAttributes, (uint)(m_invocationFlags & ~INVOCATION_FLAGS.INVOCATION_FLAGS_SPECIAL_FIELD));
diff --git a/src/mscorlib/src/System/Reflection/MethodBase.cs b/src/mscorlib/src/System/Reflection/MethodBase.cs
index f80c1701ad..afccf27dd7 100644
--- a/src/mscorlib/src/System/Reflection/MethodBase.cs
+++ b/src/mscorlib/src/System/Reflection/MethodBase.cs
@@ -33,7 +33,7 @@ namespace System.Reflection
         // method
         INVOCATION_FLAGS_IS_CTOR = 0x00000010,
         INVOCATION_FLAGS_RISKY_METHOD = 0x00000020,
-        INVOCATION_FLAGS_NON_W8P_FX_API = 0x00000040,
+        /* unused 0x00000040 */
         INVOCATION_FLAGS_IS_DELEGATE_CTOR = 0x00000080,
         INVOCATION_FLAGS_CONTAINS_STACK_POINTERS = 0x00000100,
         // field
diff --git a/src/mscorlib/src/System/Reflection/MethodInfo.cs b/src/mscorlib/src/System/Reflection/MethodInfo.cs
index 89c608b542..2205ddac32 100644
--- a/src/mscorlib/src/System/Reflection/MethodInfo.cs
+++ b/src/mscorlib/src/System/Reflection/MethodInfo.cs
@@ -98,37 +98,6 @@ namespace System.Reflection
         private object m_keepalive;
         private INVOCATION_FLAGS m_invocationFlags;
 
-#if FEATURE_APPX
-        private bool IsNonW8PFrameworkAPI()
-        {
-            if (m_declaringType.IsArray && IsPublic && !IsStatic)
-                return false;
-
-            RuntimeAssembly rtAssembly = GetRuntimeAssembly();
-            if (rtAssembly.IsFrameworkAssembly())
-            {
-                int ctorToken = rtAssembly.InvocableAttributeCtorToken;
-                if (System.Reflection.MetadataToken.IsNullToken(ctorToken) ||
-                    !CustomAttribute.IsAttributeDefined(GetRuntimeModule(), MetadataToken, ctorToken))
-                    return true;
-            }
-
-            if (GetRuntimeType().IsNonW8PFrameworkAPI())
-                return true;
-
-            if (IsGenericMethod && !IsGenericMethodDefinition)
-            {
-                foreach (Type t in GetGenericArguments())
-                {
-                    if (((RuntimeType)t).IsNonW8PFrameworkAPI())
-                        return true;
-                }
-            }
-
-            return false;
-        }
-#endif
-
         internal INVOCATION_FLAGS InvocationFlags
         {
             get
@@ -179,11 +148,6 @@ namespace System.Reflection
                         }
                     }
 
-#if FEATURE_APPX
-                    if (AppDomain.ProfileAPICheck && IsNonW8PFrameworkAPI())
-                        invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API;
-#endif // FEATURE_APPX
-
                     m_invocationFlags = invocationFlags | INVOCATION_FLAGS.INVOCATION_FLAGS_INITIALIZED;
                 }
 
@@ -591,20 +555,6 @@ namespace System.Reflection
         {
             object[] arguments = InvokeArgumentsCheck(obj, invokeAttr, binder, parameters, culture);
 
-            #region Security Check
-            INVOCATION_FLAGS invocationFlags = InvocationFlags;
-
-#if FEATURE_APPX
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", FullName));
-            }
-#endif
-            #endregion
-
             return UnsafeInvokeInternal(obj, parameters, arguments);
         }
 
diff --git a/src/mscorlib/src/System/Resources/ResourceManager.cs b/src/mscorlib/src/System/Resources/ResourceManager.cs
index 94bc720863..c60e8222fe 100644
--- a/src/mscorlib/src/System/Resources/ResourceManager.cs
+++ b/src/mscorlib/src/System/Resources/ResourceManager.cs
@@ -953,7 +953,7 @@ namespace System.Resources
                 {
                     // Cannot load the WindowsRuntimeResourceManager when in a compilation process, since it
                     // lives in System.Runtime.WindowsRuntime and only mscorlib may be loaded for execution.
-                    if (AppDomain.IsAppXModel() && !AppDomain.IsAppXNGen)
+                    if (AppDomain.IsAppXModel())
                     {
                         s_IsAppXModel = true;
 
diff --git a/src/mscorlib/src/System/RtType.cs b/src/mscorlib/src/System/RtType.cs
index 047e2e21ee..9bdeab0f31 100644
--- a/src/mscorlib/src/System/RtType.cs
+++ b/src/mscorlib/src/System/RtType.cs
@@ -2431,65 +2431,6 @@ namespace System
         private IntPtr m_cache;
         internal IntPtr m_handle;
 
-#if FEATURE_APPX
-        private INVOCATION_FLAGS m_invocationFlags;
-
-        internal bool IsNonW8PFrameworkAPI()
-        {
-            if (IsGenericParameter)
-                return false;
-
-            if (HasElementType)
-                return ((RuntimeType)GetElementType()).IsNonW8PFrameworkAPI();
-
-            if (IsSimpleTypeNonW8PFrameworkAPI())
-                return true;
-
-            if (IsGenericType && !IsGenericTypeDefinition)
-            {
-                foreach (Type t in GetGenericArguments())
-                {
-                    if (((RuntimeType)t).IsNonW8PFrameworkAPI())
-                        return true;
-                }
-            }
-
-            return false;
-        }
-
-        private bool IsSimpleTypeNonW8PFrameworkAPI()
-        {
-            RuntimeAssembly rtAssembly = GetRuntimeAssembly();
-            if (rtAssembly.IsFrameworkAssembly())
-            {
-                int ctorToken = rtAssembly.InvocableAttributeCtorToken;
-                if (System.Reflection.MetadataToken.IsNullToken(ctorToken) ||
-                    !CustomAttribute.IsAttributeDefined(GetRuntimeModule(), MetadataToken, ctorToken))
-                    return true;
-            }
-
-            return false;
-        }
-
-        internal INVOCATION_FLAGS InvocationFlags
-        {
-            get
-            {
-                if ((m_invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_INITIALIZED) == 0)
-                {
-                    INVOCATION_FLAGS invocationFlags = INVOCATION_FLAGS.INVOCATION_FLAGS_UNKNOWN;
-
-                    if (AppDomain.ProfileAPICheck && IsNonW8PFrameworkAPI())
-                        invocationFlags |= INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API;
-
-                    m_invocationFlags = invocationFlags | INVOCATION_FLAGS.INVOCATION_FLAGS_INITIALIZED;
-                }
-
-                return m_invocationFlags;
-            }
-        }
-#endif // FEATURE_APPX
-
         internal static readonly RuntimeType ValueType = (RuntimeType)typeof(System.ValueType);
         internal static readonly RuntimeType EnumType = (RuntimeType)typeof(System.Enum);
 
@@ -4859,28 +4800,11 @@ namespace System
             RuntimeMethodHandleInternal runtime_ctor = default(RuntimeMethodHandleInternal);
             bool bNeedSecurityCheck = true;
             bool bCanBeCached = false;
-            bool bSecurityCheckOff = false;
+            bool bSecurityCheckOff;
 
             if (!skipCheckThis)
                 CreateInstanceCheckThis();
 
-            if (!fillCache)
-                bSecurityCheckOff = true;
-
-#if FEATURE_APPX
-            INVOCATION_FLAGS invocationFlags = InvocationFlags;
-            if ((invocationFlags & INVOCATION_FLAGS.INVOCATION_FLAGS_NON_W8P_FX_API) != 0)
-            {
-                RuntimeAssembly caller = RuntimeAssembly.GetExecutingAssembly(ref stackMark);
-                if (caller != null && !caller.IsSafeForReflection())
-                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_APIInvalidForCurrentContext", this.FullName));
-
-                // Allow it because the caller is framework code, but don't cache the result
-                // because we need to do the stack walk every time this type is instantiated.
-                bSecurityCheckOff = false;
-                bCanBeCached = false;
-            }
-#endif
             bSecurityCheckOff = true;       // CoreCLR does not use security at all.   
 
             Object instance = RuntimeTypeHandle.CreateInstance(this, publicOnly, bSecurityCheckOff, ref bCanBeCached, ref runtime_ctor, ref bNeedSecurityCheck);
diff --git a/src/vm/appdomain.cpp b/src/vm/appdomain.cpp
index e63890f830..127dbbadd3 100644
--- a/src/vm/appdomain.cpp
+++ b/src/vm/appdomain.cpp
@@ -2747,10 +2747,6 @@ void SystemDomain::LoadBaseSystemClasses()
     _ASSERTE(!g_pEnumClass->IsValueType());
 
     // Load System.RuntimeType
-    // We need to load this after ValueType and Enum because RuntimeType now
-    // contains an enum field (m_invocationFlags). Otherwise INVOCATION_FLAGS
-    // would be treated as a reference type and clr!SigPointer::GetTypeHandleThrowing
-    // throws an exception.
     g_pRuntimeTypeClass = MscorlibBinder::GetClass(CLASS__CLASS);
     _ASSERTE(g_pRuntimeTypeClass->IsFullyLoaded());
 
diff --git a/src/vm/appdomainnative.cpp b/src/vm/appdomainnative.cpp
index 7ac3b186d9..de97fc5bb7 100644
--- a/src/vm/appdomainnative.cpp
+++ b/src/vm/appdomainnative.cpp
@@ -387,12 +387,8 @@ enum
 
     APPX_FLAGS_APPX_MODEL =         0x02,
     APPX_FLAGS_APPX_DESIGN_MODE =   0x04,
-    APPX_FLAGS_APPX_NGEN =          0x08,
     APPX_FLAGS_APPX_MASK =          APPX_FLAGS_APPX_MODEL |
-                                    APPX_FLAGS_APPX_DESIGN_MODE |
-                                    APPX_FLAGS_APPX_NGEN,
-
-    APPX_FLAGS_API_CHECK =          0x10,
+                                    APPX_FLAGS_APPX_DESIGN_MODE,
 };
 
 // static
@@ -410,28 +406,6 @@ INT32 QCALLTYPE AppDomainNative::GetAppXFlags()
 
         if (AppX::IsAppXDesignMode())
             flags |= APPX_FLAGS_APPX_DESIGN_MODE;
-        else
-            flags |= APPX_FLAGS_API_CHECK;
-
-        if (AppX::IsAppXNGen())
-            flags |= APPX_FLAGS_APPX_NGEN;
-    }
-
-    //
-    // 0: normal (only check in non-dev-mode APPX)
-    // 1: always check
-    // 2: never check
-    //
-    switch (g_pConfig->GetWindows8ProfileAPICheckFlag())
-    {
-        case 1:
-            flags |= APPX_FLAGS_API_CHECK;
-            break;
-        case 2:
-            flags &= ~APPX_FLAGS_API_CHECK;
-            break;
-        default:
-            break;
     }
 
     END_QCALL;
diff --git a/src/vm/eeconfig.cpp b/src/vm/eeconfig.cpp
index a44039d1ec..b881c43168 100644
--- a/src/vm/eeconfig.cpp
+++ b/src/vm/eeconfig.cpp
@@ -1281,10 +1281,6 @@ HRESULT EEConfig::sync()
 
     dwSleepOnExit = CLRConfig::GetConfigValue(CLRConfig::UNSUPPORTED_SleepOnExit);
 
-#ifdef FEATURE_APPX
-    dwWindows8ProfileAPICheckFlag = CLRConfig::GetConfigValue(CLRConfig::INTERNAL_Windows8ProfileAPICheckFlag);
-#endif
-
     return hr;
 }
 
diff --git a/src/vm/eeconfig.h b/src/vm/eeconfig.h
index 8e21c445da..2e8911656f 100644
--- a/src/vm/eeconfig.h
+++ b/src/vm/eeconfig.h
@@ -1262,14 +1262,6 @@ private:
 public:
     DWORD GetSleepOnExit()
     { return dwSleepOnExit; }
-
-#if FEATURE_APPX
-private:
-    DWORD dwWindows8ProfileAPICheckFlag;
-
-public:
-    DWORD GetWindows8ProfileAPICheckFlag() { return dwWindows8ProfileAPICheckFlag; }
-#endif
 };
 
 
diff --git a/src/vm/mscorlib.h b/src/vm/mscorlib.h
index f0850b7ec2..244b6900ba 100644
--- a/src/vm/mscorlib.h
+++ b/src/vm/mscorlib.h
@@ -226,9 +226,6 @@ DEFINE_CLASS_U(System,                 RuntimeType,            ReflectClassBaseO
 DEFINE_FIELD_U(m_cache,                ReflectClassBaseObject,        m_cache)
 DEFINE_FIELD_U(m_handle,               ReflectClassBaseObject,        m_typeHandle)
 DEFINE_FIELD_U(m_keepalive,            ReflectClassBaseObject,        m_keepalive)
-#ifdef FEATURE_APPX
-DEFINE_FIELD_U(m_invocationFlags,      ReflectClassBaseObject,        m_invocationFlags)
-#endif
 DEFINE_CLASS(CLASS,                 System,                 RuntimeType)
 DEFINE_FIELD(CLASS,                 TYPEHANDLE,             m_handle)
 DEFINE_METHOD(CLASS,                GET_PROPERTIES,         GetProperties,              IM_BindingFlags_RetArrPropertyInfo)
diff --git a/src/vm/object.h b/src/vm/object.h
index 65969bf20a..fad5f74f39 100644
--- a/src/vm/object.h
+++ b/src/vm/object.h
@@ -1284,9 +1284,6 @@ protected:
     OBJECTREF           m_keepalive;
     OBJECTREF           m_cache;
     TypeHandle          m_typeHandle;
-#ifdef FEATURE_APPX
-    UINT32              m_invocationFlags;
-#endif
 
 #ifdef _DEBUG
     void TypeCheck()