Roadmap: move WASM gallery from C→emcc to MLIR→LLVM→emcc?

[godofecht]

Context

Issue #221 tracks making Flow → MLIR → WASM first-class for gfx + preload (motivated by doom-flow).

Today:

• ./flow wasm --backend=mlir works for hello-class console programs
• Gallery games + doom-flow Pages use C → emcc
• Child codegen bugs (unsigned types, null ptrs, memref/GEP) block snake-class gfx on MLIR

Questions for the project

1. Is MLIR→WASM the intended long-term browser path, with C kept as a fallback?
2. Should the public /wasm/ gallery migrate once snake/tetris pass on MLIR, or stay C forever for stability?
3. What’s the bar before documenting “prefer --backend=mlir for new WASM demos”?

Concrete blockers (filed as issues)

• #222 — unsigned uN → iN
• #223 — null → llvm.mlir.zero
• #224 — memref vs GEP
• #225 — --preload / --link on mlir wasm

Happy to validate patches against doom-flow’s custom scripts/build_wasm.sh once gfx smoke works.