cranelift-jit-demo VS wit-bindgen

I'm working on a small stack-based programming language. I'm currently at a stage where I'm trying to compile it using Cranelift. Altrough the Cranelift documentation is extensive, I'm lacking a broader picture on how to approach some things like heap-allocations and stack-management. The only example project I found are cranelift-jit-demo and this wonderful post.

First, it's much easier than you think, I swear. I strongly suggest that you start with the cranelift JIT toy language demo, it has everything that you need to get started.

Fyi I've checked a few (from here; https://github.com/appcypher/awesome-wasm-langs): - assembly script complier is written is typescript/javascript and in theory could be compiled to wasm, and hence could be embedded, but it is only theory as noone has managed to complete this flow - rust-driver requires the linker and calls it as an external tool to link the rustcore to the user code. without the core lib i could not manage to create anything usable. - zig (somewhat similar to rust): on discord some experr said it cannot be embedded and he see no option/plan for it. - lua: they have lua runtime running in wasm, but no transpiller to wasm I've also checked a few other without any success and closest I coild get was the example language for cranelift (https://github.com/bytecodealliance/cranelift-jit-demo)

JITs are somehow more tricky and differ in the a few points including: a) Codegen is much more time critical. b) JITs must know what's allready generated and what isn't. c) JITs often rely on informations only generated at runtime and must respond to that. See here for a JIT example witten with cranelift: https://github.com/bytecodealliance/cranelift-jit-demo.

You could also try Cranelift. The resulting code isn't as optimized as with LLVM, but it's faster and pleasant to use (and is written in Rust).

Backend IRs for code generation: - Cranelift (see https://github.com/bytecodealliance/cranelift-jit-demo as well as the messages on the Zulip chat if you get stuck)

As for LLVM, I'm not sure if there are any tutorials but I would really advise writing a bytecode interpreter first, unless you already have some grasp of assembly. However, this repository: https://github.com/bytecodealliance/cranelift-jit-demo is really great for learning cranelift which is essentially an LLVM alternative.

It was mainly built for wasm compilation. So no it is not married to rust. https://github.com/bytecodealliance/cranelift-jit-demo

The component model is already shipping in Wasmtime, and will be stable for use in Node.js and in browsers via jco (https://github.com/bytecodealliance/jco) soon. WASI Preview 2 will be done in December or January, giving component model users a stable set of interfaces to use for scheduling, streams, and higher level functionality like stdio, filesystem, sockets, and http on an opt-in basis. You should look at wit-bindgen (https://github.com/bytecodealliance/wit-bindgen) to see some of the languages currently supported, and more that will be mature enough to use very soon (https://github.com/bytecodealliance/componentize-py)

Right now jco will automatically generate the JS glue code which implements a Component Model runtime on top of the JS engine's existing WebAssembly implementation. So, yes, Components are a composition of Wasm Modules and JS code is handling passing values from one module/instance to another. You still get the performance benefits of running computation in Wasm.

One day further down the standardization road, we would like to see Web engines ship a native implementation of the Component Model, which might be able to make certain optimizations that the JS implementation cannot. Until then you can consider jco a polyfill for a native implementation, and it still gives you the power to compose isolated programs written in many languages and run them in many different contexts, including the Web.

(Disclosure: I am co-chair of WASI, Wasmtime maintainer, implemented many parts of WASI/CM)

Thank you!

To your point, the primary consideration for choosing the languages is their support for WebAssembly, and WASI in particular.

Due to Spin's heavy use of WASI and the component model, languages that have first party support in the WIT bindings generator (https://github.com/bytecodealliance/wit-bindgen) are the easiest to implement, followed by languages that can be built on top of the support for those with first party support.

For example, the JavaScript support is built by embedding QuickJS (in particular, Shopify's Javy project — https://github.com/fermyon/spin-js-sdk), which then uses the Rust SDK.

There are many options, but what worked best for me is compiling with cargo-wasi and loading the resulting Wasm file with browser_wasi_shim. Using wasm32-wasi instead of wasm32-unknown-unknown requires a bit more work (the communication with JS has to be set up manually), but gives the flexibility of having just a Wasm file that can be dropped in and loaded dynamically. (There's wit-bindgen for generating wrapping code according to an interface definition but I didn't have much success with it.)

I've been playing with creating a go version of the abi for use with wit-bindgen because the current one uses cgo https://github.com/bytecodealliance/wit-bindgen

wit-bindgen - Language Binding Generator for WASM Interface Type

wit-bindgen-rust = { git = "https://github.com/bytecodealliance/wit-bindgen.git", rev = "60e3c5b41e616fee239304d92128e117dd9be0a7" }

Yep, you're right. For this, there are a few options. The ones most relevant to you are fp-bindgen, which targets Wasmer, and wit-bindgen, which targets wasmtime.

Are you evaluating if WebAssembly Component Model, its WIT format and related tooling like wit-bindgen could be a good fit for your multiple languages support?

[package] name = "sentiment" version = "0.1.0" edition = "2021" # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html [dependencies] wit-bindgen-rust = { git = "https://github.com/bytecodealliance/wit-bindgen.git", rev = "60e3c5b41e616fee239304d92128e117dd9be0a7" } vader_sentiment = { git = "https://github.com/ckw017/vader-sentiment-rust" } lazy_static = "1.4.0" [lib] crate-type = ["cdylib"]