[User Story] RyuJIT for WebAssembly (Wasm)

[JulieLeeMSFT]

We are bringing RyuJIT support to WebAssembly in .NET 11 as an early preview, focused on delivering a functional, though not yet fully optimized, experience for Blazor and .NET applications targeting Wasm.

.NET 11, the early preview, will enable basic scenarios and validate the new backend, allowing the team to gather feedback and address gaps ahead of broader migration from Mono runtime. Performance improvements, expanded feature coverage, and full consolidation are planned for subsequent releases, with .NET 12 and beyond targeting production readiness and optimized developer experience.

RyuJIT Base Line

• [Wasm RyuJIT] Object Writer #121143
• [Wasm RyuJIT] Basic Control Flow #121178
• [Wasm RyuJIT] Basic WASM codegen #121208
• Stub Generator Design/Development
• [Wasm RyuJIT] Calling Convention (Stub generator) #121215
• [Wasm RyuJIT] R2R #121257
• Interpreter Integration

Exception Handling & GC Support

• EH & GC Design
• Stack Tracing
• Conservative GC
• Shadow Stack Walker for Exception Handling

SIMD, Interop, and Basic Optimizations

• Interop/Pinvoke Design
• Interop/Pinvoke
• SIMD & Intrinsics
• Runtime Async
• Profiling (Identify key methods)
• Diagnostics (event pipe)
• Precise GC
• Performance for a few scenarios (Size & Speed)

Out of Scope (Needs to revisit later)

• Multi-threading for browser
• WASI
• WASM64

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[JulieLeeMSFT]

cc @kg, @AndyAyersMS, @adamperlin, @lewing, @janvorli, @steveisok, @SingleAccretion, @yowl.

[SingleAccretion]

Object Writer

FWIW, we have a WASM object writer downstream: https://github.com/dotnet/runtimelab/blob/feature/NativeAOT-LLVM/src/coreclr/tools/aot/ILCompiler.LLVM/CodeGen/WasmObjectWriter.cs. I presume for R2R purposes it will need to be a extended a bit to support "binary" (as opposed to relocatable) file generation.

[JulieLeeMSFT]

Object Writer

FWIW, we have a WASM object writer downstream: https://github.com/dotnet/runtimelab/blob/feature/NativeAOT-LLVM/src/coreclr/tools/aot/ILCompiler.LLVM/CodeGen/WasmObjectWriter.cs. I presume for R2R purposes it will need to be a extended a bit to support "binary" (as opposed to relocatable) file generation.

Thanks a lot, @SingleAccretion, for the pointer. @adamperlin needed it.

[yowl]

Should we add threads (for WASI) here, it's not available yet, but I hope it will be in the component model for example in the timeframes of .net 11 and 12

[JulieLeeMSFT]

Should we add threads (for WASI) here, it's not available yet, but I hope it will be in the component model for example in the timeframes of .net 11 and 12

Thanks. Added it to the potential future work. We have thought about it, but we need to go through another planning when we start .NET 12.

[JulieLeeMSFT]

Related Interpreter work to support wasm: #112748.