Make TypeBuilder.CreateType return non nullable

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/EnumBuilder.cs

@@ -39,14 +39,14 @@ public FieldBuilder DefineLiteral(string literalName, object? literalValue)
         }
 
         [return: DynamicallyAccessedMembersAttribute(DynamicallyAccessedMemberTypes.All)]
-        public TypeInfo? CreateTypeInfo()
+        public TypeInfo CreateTypeInfo()
         {
             return m_typeBuilder.CreateTypeInfo();
         }
 
         // CreateType cause EnumBuilder to be baked.
         [return: DynamicallyAccessedMembersAttribute(DynamicallyAccessedMemberTypes.All)]
-        public Type? CreateType()
+        public Type CreateType()
         {
             return m_typeBuilder.CreateType();
         }

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/ModuleBuilder.cs

@@ -852,7 +852,7 @@ private void CreateGlobalFunctionsNoLock()
                 // cannot create globals twice
                 throw new InvalidOperationException(SR.InvalidOperation_NotADebugModule);
             }
-            _globalTypeBuilder.CreateType();
+            _globalTypeBuilder.CreateTypeInfoImpl();
             _hasGlobalBeenCreated = true;
         }
 

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilder.cs

@@ -1677,16 +1677,23 @@ private EventBuilder DefineEventNoLock(string name, EventAttributes attributes,
         #region Create Type
 
         [return: DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
-        public TypeInfo? CreateTypeInfo()
+        public TypeInfo CreateTypeInfo()
         {
-            lock (SyncRoot)
-            {
-                return CreateTypeNoLock();
-            }
+            TypeInfo? typeInfo = CreateTypeInfoImpl();
+            Debug.Assert(typeInfo != null);
+            return typeInfo;
+        }
+
+        [return: DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
+        public Type CreateType()
+        {
+            Type? type = CreateTypeInfoImpl();
+            Debug.Assert(type != null);
+            return type;
         }
 
         [return: DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
-        public Type? CreateType()
+        internal TypeInfo? CreateTypeInfoImpl()
         {
             lock (SyncRoot)
             {

src/libraries/Common/src/System/Reflection/Emit/IgnoreAccessChecksToAttributeBuilder.cs

@@ -95,7 +95,7 @@ public static ConstructorInfo AddToModule(ModuleBuilder mb)
             attributeTypeBuilder.SetCustomAttribute(customAttributeBuilder);
 
             // Make the TypeInfo real so the constructor can be used.
-            return attributeTypeBuilder.CreateTypeInfo()!.DeclaredConstructors.Single();
+            return attributeTypeBuilder.CreateTypeInfo().DeclaredConstructors.Single();
         }
     }
 }

src/libraries/System.Linq.Expressions/src/System/Linq/Expressions/Compiler/DelegateHelpers.cs

@@ -122,7 +122,7 @@ private static Type MakeNewCustomDelegate(Type[] types)
                 TypeBuilder builder = AssemblyGen.DefineDelegateType("Delegate" + types.Length);
                 builder.DefineConstructor(ctorAttributes, CallingConventions.Standard, delegateCtorSignature).SetImplementationFlags(implAttributes);
                 builder.DefineMethod("Invoke", invokeAttributes, returnType, parameters).SetImplementationFlags(implAttributes);
-                return builder.CreateTypeInfo()!;
+                return builder.CreateTypeInfo();
             }
             else
             {

src/libraries/System.Private.Xml/src/System/Xml/Serialization/XmlSerializationILGen.cs

@@ -299,7 +299,7 @@ internal string GenerateBaseSerializer(string baseSerializer, string readerClass
 
             baseSerializerTypeBuilder.DefineDefaultConstructor(
                 MethodAttributes.Family | MethodAttributes.HideBySig | MethodAttributes.SpecialName | MethodAttributes.RTSpecialName);
-            Type baseSerializerType = baseSerializerTypeBuilder.CreateTypeInfo()!.AsType();
+            Type baseSerializerType = baseSerializerTypeBuilder.CreateType();
             CreatedTypes.Add(baseSerializerType.Name, baseSerializerType);
 
             return baseSerializer;
@@ -396,7 +396,7 @@ internal string GenerateTypedSerializer(string readMethod, string writeMethod, X
                 ilg.EndMethod();
             }
             typedSerializerTypeBuilder.DefineDefaultConstructor(CodeGenerator.PublicMethodAttributes);
-            Type typedSerializerType = typedSerializerTypeBuilder.CreateTypeInfo()!.AsType();
+            Type typedSerializerType = typedSerializerTypeBuilder.CreateType();
             CreatedTypes.Add(typedSerializerType.Name, typedSerializerType);
 
             return typedSerializerType.Name;
@@ -558,7 +558,7 @@ internal void GenerateSerializerContract(string className, XmlMapping[] xmlMappi
             ilg.Call(baseCtor);
             ilg.EndMethod();
             // Instantiate type
-            Type serializerContractType = serializerContractTypeBuilder.CreateTypeInfo()!.AsType();
+            Type serializerContractType = serializerContractTypeBuilder.CreateType();
             CreatedTypes.Add(serializerContractType.Name, serializerContractType);
         }
 

src/libraries/System.Private.Xml/src/System/Xml/Serialization/XmlSerializationReaderILGen.cs

@@ -255,7 +255,7 @@ internal void GenerateEnd(string[] methods, XmlMapping[] xmlMappings, Type[] typ
 
             this.typeBuilder.DefineDefaultConstructor(
                 CodeGenerator.PublicMethodAttributes);
-            Type readerType = this.typeBuilder.CreateTypeInfo()!.AsType();
+            Type readerType = this.typeBuilder.CreateType();
             CreatedTypes.Add(readerType.Name, readerType);
         }
 

src/libraries/System.Private.Xml/src/System/Xml/Serialization/XmlSerializationWriterILGen.cs

@@ -68,7 +68,7 @@ internal Type GenerateEnd()
             GenerateInitCallbacksMethod();
             this.typeBuilder.DefineDefaultConstructor(
                 CodeGenerator.PublicMethodAttributes);
-            return this.typeBuilder.CreateTypeInfo()!.AsType();
+            return this.typeBuilder.CreateType();
         }
 
         [RequiresUnreferencedCode("calls GenerateTypeElement")]

src/libraries/System.Private.Xml/src/System/Xml/Xsl/IlGen/XmlILModule.cs

@@ -239,7 +239,7 @@ public void BakeMethods()
 
             if (!_useLRE)
             {
-                typBaked = _typeBldr!.CreateTypeInfo()!.AsType();
+                typBaked = _typeBldr!.CreateType();
 
                 // Replace all MethodInfos in this.methods
                 methodsBaked = new Hashtable(_methods.Count);

src/libraries/System.Reflection.DispatchProxy/src/System/Reflection/DispatchProxyGenerator.cs

@@ -309,7 +309,7 @@ private void Complete()
             internal GeneratedTypeInfo CreateType()
             {
                 this.Complete();
-                return new GeneratedTypeInfo(_tb.CreateType()!, _methodInfos.ToArray());
+                return new GeneratedTypeInfo(_tb.CreateType(), _methodInfos.ToArray());
             }
 
             internal void AddInterfaceImpl([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type iface)

src/libraries/System.Reflection.Emit.ILGeneration/tests/CustomAttributeBuilderTests.cs

@@ -422,7 +422,7 @@ public static IEnumerable<object[]> Ctor_RefEmitParameters_TestData()
             setMethodGenerator.Emit(OpCodes.Ret);
             propertyBuilder.SetSetMethod(setMethod);
 
-            Type createdType = typeBuilder.CreateTypeInfo().AsType();
+            Type createdType = typeBuilder.CreateType();
 
             // ConstructorBuilder, PropertyInfo, FieldInfo
             yield return new object[]
@@ -555,7 +555,7 @@ public static void ConstructorHasNonStandardCallingConvention_ThrowsArgumentExce
             ConstructorBuilder constructorBuilder = typeBuilder.DefineConstructor(MethodAttributes.Public, callingConvention, new Type[0]);
             constructorBuilder.GetILGenerator().Emit(OpCodes.Ret);
 
-            ConstructorInfo con = typeBuilder.CreateTypeInfo().AsType().GetConstructor(new Type[0]);
+            ConstructorInfo con = typeBuilder.CreateType().GetConstructor(new Type[0]);
 
             AssertExtensions.Throws<ArgumentException>(null, () => new CustomAttributeBuilder(con, new object[0]));
             AssertExtensions.Throws<ArgumentException>(null, () => new CustomAttributeBuilder(con, new object[0], new FieldInfo[0], new object[0]));
@@ -1068,7 +1068,7 @@ private static Type CreateEnum(Type underlyingType, params object[] literalValue
             {
                 enumBuilder.DefineLiteral("Value" + i, literalValues[i]);
             }
-            return enumBuilder.CreateTypeInfo().AsType();
+            return enumBuilder.CreateType();
         }
     }
 

src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/Emit1Tests.cs

@@ -22,7 +22,7 @@ public void PosTest1()
             ilgen.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType1 = type.CreateTypeInfo().AsType();
+            Type createdType1 = type.CreateType();
             MethodInfo createdMethod1 = createdType1.GetMethod("meth1");
 
             TypeBuilder type2 = module.DefineType("C2", TypeAttributes.Public);
@@ -35,7 +35,7 @@ public void PosTest1()
             ilgen2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod2 = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value from meth1
@@ -56,7 +56,7 @@ public void PosTest2()
             ilGenerator1.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType1 = type1.CreateTypeInfo().AsType();
+            Type createdType1 = type1.CreateType();
             MethodInfo createdMethod1 = createdType1.GetMethod("meth1");
 
             TypeBuilder type2 = module.DefineType("C2", TypeAttributes.Public);
@@ -69,7 +69,7 @@ public void PosTest2()
             ilGenerator2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod2 = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value 'methodRet'
@@ -93,7 +93,7 @@ public void PosTest3()
             ilGenerator.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType1 = type1.CreateTypeInfo().AsType();
+            Type createdType1 = type1.CreateType();
             MethodInfo createdMethod1 = createdType1.GetMethod("meth1");
             MethodInfo genericMethod = createdMethod1.MakeGenericMethod(typeof(int));
 
@@ -107,7 +107,7 @@ public void PosTest3()
             ilGenerator2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod2 = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value 'methodRet'
@@ -131,7 +131,7 @@ public void PosTest4()
             ilGenerator1.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType1 = type1.CreateTypeInfo().AsType();
+            Type createdType1 = type1.CreateType();
             Type genericType = createdType1.MakeGenericType(typeof(int));
             MethodInfo genericMethod = genericType.GetMethod("meth1");
 
@@ -145,7 +145,7 @@ public void PosTest4()
             ilGenerator2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod2 = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value 'methodRet'
@@ -170,7 +170,7 @@ public void PosTest5()
             ilGenerator1.Emit(OpCodes.Ret);
 
             // create the type where this method is in
-            Type createdType1 = type1.CreateTypeInfo().AsType();
+            Type createdType1 = type1.CreateType();
             Type genericType = createdType1.MakeGenericType(typeof(int));
             MethodInfo createdMethod1 = genericType.GetMethod("meth1");
             MethodInfo genericMethod = createdMethod1.MakeGenericMethod(typeof(string));
@@ -185,7 +185,7 @@ public void PosTest5()
             ilGenerator2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod2 = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value 'methodRet'

src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/Emit3Tests.cs

@@ -81,7 +81,7 @@ public void PosTest1()
             ilGenerator.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("meth1");
 
             Assert.True((bool)createdMethod.Invoke(null, null));
@@ -105,7 +105,7 @@ public void PosTest2()
             ilGenerator.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType = tb.CreateTypeInfo().AsType();
+            Type createdType = tb.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("meth1");
 
             Assert.True((bool)createdMethod.Invoke(null, null));
@@ -126,7 +126,7 @@ public void PosTest3()
             ilGenerator.Emit(OpCodes.Ret);
 
             // create the type where this method is in
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("meth1");
 
             Assert.True((bool)createdMethod.Invoke(null, null));
@@ -205,7 +205,7 @@ public void PosTest4()
             ilGenerator.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("meth1");
 
             Assert.True((bool)createdMethod.Invoke(null, null));

src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/Emit5Tests.cs

@@ -69,7 +69,7 @@ static MethodInfo GetCode(int num)
                 ilg.Emit(OpCodes.Ret);
 
                 // Create the type where this method is in
-                Type createdType = type.CreateTypeInfo().AsType();
+                Type createdType = type.CreateType();
                 MethodInfo createdMethod = createdType.GetMethod("meth1");
 
                 return createdMethod;
@@ -135,7 +135,7 @@ static MethodInfo GetCode(int num)
                 ilg.Emit(OpCodes.Ret);
 
                 // Create the type where this method is in
-                Type createdType = type.CreateTypeInfo().AsType();
+                Type createdType = type.CreateType();
                 return createdType.GetMethod("meth1");
             }
         }
@@ -209,7 +209,7 @@ static MethodInfo GetCode(int num)
                 ilg.Emit(OpCodes.Ret);
 
                 // Create the type where this method is in
-                Type createdType = type.CreateTypeInfo().AsType();
+                Type createdType = type.CreateType();
                 return createdType.GetMethod("meth1");
             }
         }
@@ -256,7 +256,7 @@ static MethodInfo GetCode()
                 ilg.Emit(OpCodes.Ret);
 
                 // Create the type where this method is in
-                Type createdType = type.CreateTypeInfo().AsType();
+                Type createdType = type.CreateType();
                 return createdType.GetMethod("meth1");
             }
         }
@@ -297,7 +297,7 @@ static MethodInfo GetCode()
                 ilg.Emit(OpCodes.Ret);
 
                 // Create the type where this method is in
-                Type createdType = type.CreateTypeInfo().AsType();
+                Type createdType = type.CreateType();
                 return createdType.GetMethod("meth1");
             }
         }

src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/EmitWriteLineTests.cs

@@ -23,7 +23,7 @@ public void EmitWriteLineTests()
             ilGenerator1.Emit(OpCodes.Ret);
 
             // Create the type where this method is in
-            Type createdType1 = type1.CreateTypeInfo().AsType();
+            Type createdType1 = type1.CreateType();
             FieldInfo createdField = createdType1.GetField("field1");
 
             TypeBuilder type2 = module.DefineType("C2", TypeAttributes.Public);
@@ -39,7 +39,7 @@ public void EmitWriteLineTests()
             ilGenerator2.Emit(OpCodes.Ret);
 
             // Create the type whose method will be invoking the MethodInfo method
-            Type createdType2 = type2.CreateTypeInfo().AsType();
+            Type createdType2 = type2.CreateType();
             MethodInfo createdMethod = createdType2.GetMethod("meth2");
 
             // meth2 should invoke meth1 which should return value from meth1

src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/ExceptionEmitTests.cs

@@ -44,7 +44,7 @@ public void TestExceptionEmitCalls()
             ilGenerator.Emit(OpCodes.Ldloc_S, tmp1);
             ilGenerator.Emit(OpCodes.Ret);
 
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("DoThrow");
 
             Assert.Equal(-1, createdMethod.Invoke(null, new object[] { true })); // Throws

src/libraries/System.Reflection.Emit.ILGeneration/tests/ParameterBuilder/SetCustomAttributeTests.cs

@@ -24,7 +24,7 @@ public void SetCustomAttribute_CustomAttributeBuilder()
 
             CustomAttributeBuilder attribute = new CustomAttributeBuilder(constructor, new object[] { 4 }, new FieldInfo[] { field }, new object[] { "hello" });
             parameter.SetCustomAttribute(attribute);
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("method1");
             ParameterInfo createdParameter = createdMethod.GetParameters()[0];
 
@@ -46,7 +46,7 @@ public void SetCustomAttribute_ConstructorInfo_ByteArray()
             ilGenerator.Emit(OpCodes.Ret);
 
             parameter.SetCustomAttribute(typeof(ParameterBuilderCustomAttribute).GetConstructor(new Type[] { typeof(bool)}), new byte[] { 1, 0, 1, 0, 0});
-            Type createdType = type.CreateTypeInfo().AsType();
+            Type createdType = type.CreateType();
             MethodInfo createdMethod = createdType.GetMethod("method1");
             ParameterInfo createdParameter = createdMethod.GetParameters()[0];