Does AOT plan to support EMIT in the future

[DotNetNext]

Background and motivation

EMIT performs very well when running create classes and code.
It is also important in low code development

Hope to support it in AOT

       AssemblyName assemblyName = new AssemblyName("DynamicAssembly");
       AssemblyBuilder assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName, 
      AssemblyBuilderAccess.Run);
       

       ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("DynamicModule");


       TypeBuilder typeBuilder = moduleBuilder.DefineType("DynamicClass", TypeAttributes.Public);


       FieldBuilder fieldBuilder = typeBuilder.DefineField("dynamicField", typeof(string), FieldAttributes.Private);


       ConstructorBuilder constructorBuilder = typeBuilder.DefineConstructor(MethodAttributes.Public, CallingConventions.Standard, new Type[] { typeof(string) });
       ILGenerator ctorIL = constructorBuilder.GetILGenerator();
       ctorIL.Emit(OpCodes.Ldarg_0);
       ctorIL.Emit(OpCodes.Call, typeof(object).GetConstructor(Type.EmptyTypes));
       ctorIL.Emit(OpCodes.Ldarg_0);
       ctorIL.Emit(OpCodes.Ldarg_1);
       ctorIL.Emit(OpCodes.Stfld, fieldBuilder);
       ctorIL.Emit(OpCodes.Ret);


       MethodBuilder methodBuilder = typeBuilder.DefineMethod("GetDynamicField", MethodAttributes.Public, typeof(string), Type.EmptyTypes);
       ILGenerator methodIL = methodBuilder.GetILGenerator();
       methodIL.Emit(OpCodes.Ldarg_0);
       methodIL.Emit(OpCodes.Ldfld, fieldBuilder);
       methodIL.Emit(OpCodes.Ret);

  
       Type dynamicType = typeBuilder.CreateType();


       object dynamicInstance = Activator.CreateInstance(dynamicType, "Hello, Dynamic World!");


       MethodInfo methodInfo = dynamicType.GetMethod("GetDynamicField");
       string result = (string)methodInfo.Invoke(dynamicInstance, null);

       Console.WriteLine(result);  

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Issue Details

---

Background and motivation

EMIT performs very well when running create classes and code.
It is also important in low code development

Hope to support it in AOT

API Proposal

// 创建一个程序集
AssemblyName assemblyName = new AssemblyName("DynamicAssembly");
AssemblyBuilder assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.Run);

    ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("DynamicModule");


    TypeBuilder typeBuilder = moduleBuilder.DefineType("DynamicClass", TypeAttributes.Public);


    FieldBuilder fieldBuilder = typeBuilder.DefineField("dynamicField", typeof(string), FieldAttributes.Private);


    ConstructorBuilder constructorBuilder = typeBuilder.DefineConstructor(MethodAttributes.Public, CallingConventions.Standard, new Type[] { typeof(string) });
    ILGenerator ctorIL = constructorBuilder.GetILGenerator();
    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Call, typeof(object).GetConstructor(Type.EmptyTypes));
    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Ldarg_1);
    ctorIL.Emit(OpCodes.Stfld, fieldBuilder);
    ctorIL.Emit(OpCodes.Ret);


    MethodBuilder methodBuilder = typeBuilder.DefineMethod("GetDynamicField", MethodAttributes.Public, typeof(string), Type.EmptyTypes);
    ILGenerator methodIL = methodBuilder.GetILGenerator();
    methodIL.Emit(OpCodes.Ldarg_0);
    methodIL.Emit(OpCodes.Ldfld, fieldBuilder);
    methodIL.Emit(OpCodes.Ret);


    Type dynamicType = typeBuilder.CreateType();


    object dynamicInstance = Activator.CreateInstance(dynamicType, "Hello, Dynamic World!");


    MethodInfo methodInfo = dynamicType.GetMethod("GetDynamicField");
    string result = (string)methodInfo.Invoke(dynamicInstance, null);

    Console.WriteLine(result);  

API Usage

// Fancy the value
var c = new MyFancyCollection<int>();
c.Fancy(42);

// Getting the values out
foreach (var v in c)
    Console.WriteLine(v);

Alternative Designs

No response

Risks

No response

Author:	DotNetNext
Assignees:	-
Labels:	api-suggestion, area-System.Reflection.Emit
Milestone:	-

[huoyaoyuan]

See the current experiment:

• NativeAOT-Mint - Mono interpreter ported to Native AOT for dynamic execution support

If you want the benefit of AOT compilation together with dynamic execution, you can use ReadyToRun. Native AOT is designed for environments that doesn't allow dynamic code at all.

[DotNetNext]

It is theoretically possible to turn dynamic IL into dynamic machine language at the time of release

[huoyaoyuan]

turn dynamic IL into dynamic machine language at the time of release

How dynamic it would be? Source generator is mainly created for generating code at build time, with the information from existing code.

[DotNetNext]

turn dynamic IL into dynamic machine language at the time of release

How dynamic it would be? Source generator is mainly created for generating code at build time, with the information from existing code.

EMIT is used to create classes at runtime. For example, if a user wants to create a table, the table does not exist, so I need to create classes online

[DotNetNext]

Future low-code AI methods will have to be created automatically at runtime

[jkotas]

What do you expect to get out of this? The performance characteristics of a configuration like this would be very similar to CoreCLR with trimming and ReadyToRun. What prevents you from using CoreCLR with trimming and ReadyToRun?

[DotNetNext]

What do you expect to get out of this? The performance characteristics of a configuration like this would be very similar to CoreCLR with trimming and ReadyToRun. What prevents you from using CoreCLR with trimming and ReadyToRun?

ReadyToRun cannot create objects after the application starts, unlike the runtime creation of EMIT

[huoyaoyuan]

ReadyToRun cannot create objects after the application starts, unlike the runtime creation of EMIT

ReadyToRun works with JIT. You can just use Emit together with ReadyToRun.

[DotNetNext]

ReadyToRun cannot create objects after the application starts, unlike the runtime creation of EMIT

ReadyToRun works with JIT. You can just use Emit together with ReadyToRun.

【AOT+EMIT+ReadyToRun 】 Can you use it together?

[huoyaoyuan]

【AOT+EMIT+ReadyToRun 】

NativeAOT and ReadyToRun provides similar AOT compilation for different environment. NativeAOT is "full AOT" used for environment where dynamic code is disallowed. ReadyToRun is "partial AOT" and brings the benefit of AOT to environment where JIT is still allowed. Which environment are you interested in? What benefit of AOT are you caring about?

[DotNetNext]

NativeAOT and ReadyToRun provides similar AOT compilation for different environment. NativeAOT is "full AOT" used for environment where dynamic code is disallowed. ReadyToRun is "partial AOT" and brings the benefit of AOT to environment where JIT is still allowed. Which environment are you interested in? What benefit of AOT are you caring about?

Thank you very much. Got it