Delete reflection-free mode (dotnet#109857)

src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.targets

@@ -35,8 +35,6 @@ The .NET Foundation licenses this file to you under the MIT license.
 
   <!-- Set up default feature switches -->
   <PropertyGroup>
-    <UseSystemResourceKeys Condition="$(IlcDisableReflection) == 'true'">true</UseSystemResourceKeys>
-    <EventSourceSupport Condition="$(IlcDisableReflection) == 'true'">false</EventSourceSupport>
     <EventSourceSupport Condition="$(EventSourceSupport) == ''">false</EventSourceSupport>
     <UseWindowsThreadPool Condition="'$(UseWindowsThreadPool)' == '' and '$(_targetOS)' == 'win'">true</UseWindowsThreadPool>
     <DynamicCodeSupport Condition="'$(DynamicCodeSupport)' == ''">false</DynamicCodeSupport>
@@ -108,8 +106,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     <AutoInitializedAssemblies Include="System.Private.CoreLib" />
     <AutoInitializedAssemblies Include="System.Private.StackTraceMetadata" Condition="$(StackTraceSupport) != 'false'" />
     <AutoInitializedAssemblies Include="System.Private.TypeLoader" />
-    <AutoInitializedAssemblies Include="System.Private.Reflection.Execution" Condition="$(IlcDisableReflection) != 'true'" />
-    <AutoInitializedAssemblies Include="System.Private.DisabledReflection" Condition="$(IlcDisableReflection) == 'true'" />
+    <AutoInitializedAssemblies Include="System.Private.Reflection.Execution" />
   </ItemGroup>
 
   <ItemDefinitionGroup>
@@ -258,15 +255,12 @@ The .NET Foundation licenses this file to you under the MIT license.
       <IlcArg Condition="$(ServerGarbageCollection) == 'true'" Include="--runtimeopt:gcServer=1" />
       <IlcArg Condition="$(IlcGenerateCompleteTypeMetadata) == 'true'" Include="--completetypemetadata" />
       <IlcArg Condition="$(StackTraceSupport) != 'false'" Include="--stacktracedata" />
-      <IlcArg Condition="$(IlcScanReflection) != 'false' and $(IlcDisableReflection) != 'true'" Include="--scanreflection" />
+      <IlcArg Condition="$(IlcScanReflection) != 'false'" Include="--scanreflection" />
       <IlcArg Condition="$(IlcFoldIdenticalMethodBodies) == 'true' or $(StackTraceSupport) == 'false'" Include="--methodbodyfolding" />
       <IlcArg Condition="$(Optimize) == 'true' and $(OptimizationPreference) == 'Size'" Include="--Os" />
       <IlcArg Condition="$(Optimize) == 'true' and $(OptimizationPreference) == 'Speed'" Include="--Ot" />
       <IlcArg Condition="'$(_linuxLibcFlavor)' == 'bionic'" Include="--noinlinetls" />
       <IlcArg Condition="$(IlcInstructionSet) != ''" Include="--instruction-set:$(IlcInstructionSet)" />
-      <IlcArg Condition="$(IlcDisableReflection) == 'true'" Include="--reflectiondata:none" />
-      <IlcArg Condition="$(IlcDisableReflection) == 'true'" Include="--feature:System.Collections.Generic.DefaultComparers=false" />
-      <IlcArg Condition="$(IlcDisableReflection) == 'true'" Include="--feature:System.Reflection=false" />
       <IlcArg Condition="$(IlcMaxVectorTBitWidth) != ''" Include="--max-vectort-bitwidth:$(IlcMaxVectorTBitWidth)" />
       <IlcArg Condition="$(IlcSingleThreaded) == 'true'" Include="--parallelism:1" />
       <IlcArg Condition="$(IlcSystemModule) != ''" Include="--systemmodule:$(IlcSystemModule)" />
@@ -291,8 +285,6 @@ The .NET Foundation licenses this file to you under the MIT license.
       <IlcArg Condition="$(IlcResilient) != 'false'" Include="--resilient" />
       <IlcArg Include="@(UnmanagedEntryPointsAssembly->'--generateunmanagedentrypoints:%(Identity)')" />
 
-      <IlcArg Condition="$(IlcDisableReflection) == 'true'" Include="--feature:System.Reflection.IsReflectionExecutionAvailable=false" />
-
       <!-- The managed debugging support in libraries is unused - trim it -->
       <IlcArg Condition="'$(DebuggerSupport)' != 'true'" Include="--feature:System.Diagnostics.Debugger.IsSupported=false" />
 

src/coreclr/nativeaot/System.Private.CoreLib/src/System.Private.CoreLib.csproj

@@ -8,7 +8,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <ILLinkSubstitutionsXmls Include="ILLink\ILLink.Substitutions.xml" />
     <ILLinkLinkAttributesXmls Include="ILLink\ILLink.LinkAttributes.xml" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)'=='true'">

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Collections/Generic/Comparer.NativeAot.cs

@@ -13,9 +13,6 @@ namespace System.Collections.Generic
 {
     public abstract partial class Comparer<T> : IComparer, IComparer<T>
     {
-        [FeatureSwitchDefinition("System.Collections.Generic.DefaultComparers")]
-        private static bool SupportsGenericIComparableInterfaces => true;
-
         [Intrinsic]
         private static Comparer<T> Create()
         {
@@ -24,11 +21,7 @@ private static Comparer<T> Create()
             // This body serves as a fallback when instantiation-specific implementation is unavailable.
             // If that happens, the compiler ensures we generate data structures to make the fallback work
             // when this method is compiled.
-            if (SupportsGenericIComparableInterfaces)
-            {
-                return Unsafe.As<Comparer<T>>(ComparerHelpers.GetComparer(typeof(T).TypeHandle));
-            }
-            return new ObjectComparer<T>();
+            return Unsafe.As<Comparer<T>>(ComparerHelpers.GetComparer(typeof(T).TypeHandle));
         }
 
         public static Comparer<T> Default { [Intrinsic] get; } = Create();

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Collections/Generic/EqualityComparer.NativeAot.cs

@@ -13,9 +13,6 @@ namespace System.Collections.Generic
 {
     public abstract partial class EqualityComparer<T> : IEqualityComparer, IEqualityComparer<T>
     {
-        [FeatureSwitchDefinition("System.Collections.Generic.DefaultComparers")]
-        private static bool SupportsGenericIEquatableInterfaces => true;
-
         [Intrinsic]
         private static EqualityComparer<T> Create()
         {
@@ -30,11 +27,7 @@ private static EqualityComparer<T> Create()
                 return Unsafe.As<EqualityComparer<T>>(new StringEqualityComparer());
             }
 
-            if (SupportsGenericIEquatableInterfaces)
-            {
-                return Unsafe.As<EqualityComparer<T>>(EqualityComparerHelpers.GetComparer(typeof(T).TypeHandle));
-            }
-            return new ObjectEqualityComparer<T>();
+            return Unsafe.As<EqualityComparer<T>>(EqualityComparerHelpers.GetComparer(typeof(T).TypeHandle));
         }
 
         public static EqualityComparer<T> Default { [Intrinsic] get; } = Create();

src/coreclr/nativeaot/System.Private.CoreLib/src/System/RuntimeType.cs

@@ -46,12 +46,6 @@ internal void Free()
             RuntimeImports.RhHandleFree(_runtimeTypeInfoHandle);
         }
 
-        private static bool IsReflectionDisabled => false;
-
-        private static bool DoNotThrowForNames => AppContext.TryGetSwitch("Switch.System.Reflection.Disabled.DoNotThrowForNames", out bool doNotThrow) && doNotThrow;
-        private static bool DoNotThrowForAssembly => AppContext.TryGetSwitch("Switch.System.Reflection.Disabled.DoNotThrowForAssembly", out bool doNotThrow) && doNotThrow;
-        private static bool DoNotThrowForAttributes => AppContext.TryGetSwitch("Switch.System.Reflection.Disabled.DoNotThrowForAttributes", out bool doNotThrow) && doNotThrow;
-
         internal MethodTable* ToMethodTableMayBeNull() => _pUnderlyingEEType;
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -72,9 +66,6 @@ internal RuntimeTypeInfo GetRuntimeTypeInfo()
         [MethodImpl(MethodImplOptions.NoInlining)]
         private RuntimeTypeInfo InitializeRuntimeTypeInfoHandle()
         {
-            if (IsReflectionDisabled)
-                throw new NotSupportedException(SR.Reflection_Disabled);
-
             RuntimeTypeInfo runtimeTypeInfo = ExecutionDomain.GetRuntimeTypeInfo(_pUnderlyingEEType);
 
             // We assume that the RuntimeTypeInfo unifiers pick a winner when multiple threads
@@ -648,9 +639,6 @@ public override bool IsInstanceOfType([NotNullWhen(true)] object? o)
 
         public override string ToString()
         {
-            if (IsReflectionDisabled)
-                return "0x" + ((nuint)_pUnderlyingEEType).ToString("x");
-
             return GetRuntimeTypeInfo().ToString();
         }
 
@@ -799,46 +787,31 @@ public override bool IsDefined(Type attributeType, bool inherit)
 
         public override object[] GetCustomAttributes(bool inherit)
         {
-            if (IsReflectionDisabled && DoNotThrowForAttributes)
-                return Array.Empty<object>();
-
             return GetRuntimeTypeInfo().GetCustomAttributes(inherit);
         }
 
         public override object[] GetCustomAttributes(Type attributeType, bool inherit)
         {
-            if (IsReflectionDisabled && DoNotThrowForAttributes)
-                return Array.Empty<object>();
-
             return GetRuntimeTypeInfo().GetCustomAttributes(attributeType, inherit);
         }
 
         public override IEnumerable<CustomAttributeData> CustomAttributes
         {
             get
             {
-                if (IsReflectionDisabled && DoNotThrowForAttributes)
-                    return Array.Empty<CustomAttributeData>();
-
                 return GetRuntimeTypeInfo().CustomAttributes;
             }
         }
 
         public override IList<CustomAttributeData> GetCustomAttributesData()
         {
-            if (IsReflectionDisabled && DoNotThrowForAttributes)
-                return Array.Empty<CustomAttributeData>();
-
             return GetRuntimeTypeInfo().GetCustomAttributesData();
         }
 
         public override string Name
         {
             get
             {
-                if (IsReflectionDisabled && DoNotThrowForNames)
-                    return ToString();
-
                 return GetRuntimeTypeInfo().Name;
             }
         }
@@ -847,9 +820,6 @@ public override string? Namespace
         {
             get
             {
-                if (IsReflectionDisabled && DoNotThrowForNames)
-                    return null;
-
                 return GetRuntimeTypeInfo().Namespace;
             }
         }
@@ -862,9 +832,6 @@ public override Assembly Assembly
         {
             get
             {
-                if (IsReflectionDisabled && DoNotThrowForAssembly)
-                    return Assembly.GetExecutingAssembly();
-
                 return GetRuntimeTypeInfo().Assembly;
             }
         }