WASI runtime

[vouillon]

You can produce a WASI binary by running wasm_of_ocaml with the --enable wasi flag:

wasm_of_ocaml --enable wasi foo.byte -o foo.js

This produces some Wasm code that can be directly executed by the Wizard engine:

wizeng.x86-64-linux -ext:stack-switching -ext:legacy-eh foo.assets/code.wasm

wasmtime does not support the exception handling proposal yet. Assuming that your program does not raise any exception, you can produce a binary that will work with wasmtime as well by adding the --enable trap-on-exception flag:

wasm_of_ocaml --enable wasi --enable trap-on-exception foo.byte -o foo.js

You can then execute it with the following command:

wasmtime -W=all-proposals=y foo.assets/code.wasm

Note that we keep the same output convention, at least for now: a JavaScript file foo.js and a directory foo.assets containing the Wasm code. The JavaScript file can be use to run the WASI binary with node.