System.Reflection work planned for .NET 8

[steveharter]

This issue captures the planned work for .NET 8. This list is expected to change throughout the release cycle according to ongoing planning and discussions, with possible additions and subtractions to the scope.

Planned for .NET 8

Function Pointers

• [original issue]: Representation of function pointer types in the reflection stack
• [API Proposal]: Reflection introspection support for FunctionPointer
• [API Proposal]: Reflection invoke support for FunctionPointer
• [API Proposal]: IL Emit support for FunctionPointer

Invoke

• [prototype created] [User Story]: Developers using reflection invoke should be able to use ref struct
  
• [prototype created] [API Proposal]: byref parameter collection for invoke
• [prototype created] Support byref invoke for return parameter and target (plumbing; no public API changes)
• [prototype created] [API Proposal] Add reflection support to byref-like types
• Change IL Emit invoke path to use function pointers and OpCodes.Calli
• Support fast field get\set.

Activator

• API proposal: Activator.CreateFactory and ConstructorInfo.CreateDelegate
• Have ConstructorInfo use Activator.CreateInstance() instead of emit for default constructors

Misc backlog

The following are higher priority issues that are affecting the community and for the most part, do not include features or bugs that have reasonable workarounds.

• Runtime: Support for reflection-invoking methods that take pointers by reference
• FileNotFoundException resource files is slowing things down ridiculously

Emit

• [partial implementation] Support equivalent of AssemblyBuilder.Save to save in-memory IL to an assembly
• Add InstructionEncoder.Switch to enable emitting switch instructions with LabelHandles

[ghost]

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Issue Details

---

[currently this is a draft for planning purposes]

This issue captures the planned work for .NET 8. This list is expected to change throughout the release cycle according to ongoing planning and discussions, with possible additions and subtractions to the scope.

Planned for .NET 8

Function Pointers

• [API Proposal]: Reflection introspection support for FunctionPointer
• [API Proposal]: Reflection invoke support for FunctionPointer
• [API Proposal]: IL Emit support for FunctionPointer

Support for by-ref like types and a fast, non-allocating invoke

• [API Proposal]: byref parameter collection for invoke
• Support for generating IL Emit for field get\set
• Change IL Emit invoke path to use function pointers and OpCodes.Calli
• Support byref invoke for return parameter and target
• [API Proposal] Add reflection support to byref-like types

The following are higher priority reflection issues that are affecting the community and for the most part, do not include features or bugs that have reasonable workarounds.

Backlog

(items to be added here)

Pending

• Support equivalent of AssemblyBuilder.Save to save in-memory IL to an assembly

Author:	steveharter
Assignees:	steveharter
Labels:	Epic, area-System.Reflection, Cost:XL
Milestone:	8.0.0

[BreyerW]

Some links are broken like Support for generating IL Emit for field get\set and Support byref invoke for return parameter and target.

[steveharter]

Closing for v8; several were partially implemented or prototyped and the description was updated to reflection that.

A new issue will be created for v9,