foth VS rustc_codegen_cranelift

I hacked up a simple forth-like system in golang, by following the overview posted in this hackernews comment-chain:

https://news.ycombinator.com/item?id=13082825

The result is here:

https://github.com/skx/foth

It's not real, but it was a pretty fun experiment regardless.

Here's one of the many forks that brings it up to 64-bit:

https://github.com/matematikaadit/jombloforth

If you like forth there's an awesome series of comments here on hacker news on building a simple variant in a few simple steps:

https://news.ycombinator.com/item?id=13082825

I took that, and built a simple forth-like system, in golang following the original recipe and breaking it down into simple steps for learning-purposes:

https://github.com/skx/foth

I'll always vote up submissions referencing anything FORTH related. For me FORTH is as much fun as lisp appears to be for others. I've never really done much with it, but I always like the simplicity and the ability to reason about it.

Sure FORTH has problems of its own, but it's always nice to use. I've hacked up a couple of simple FORTH-like systems over the years, most recently this one which was inspired by a thread on this site:

https://github.com/skx/foth

A lot of people go through guides of writing a lisp, I'd love to urge people to try writing a simple FORTH interpreter instead, or even something somewhat related such as TCL.

There's even a recipe posted in a couple of comments here:

https://news.ycombinator.com/item?id=13082825

I followed that guide to implement a simple FORTH-like system in golang:

https://github.com/skx/foth

As I was following the implementation recipe I broke it down into "educational steps". Although it isn't a true FORTH it is pretty easy to understand and useful enough to embed inside other applications.

Now and again I consider doing it again, but using a real return-stack to remove the hardcoded control-flow words from the interpreter, but I never quite find the time.

I actually hacked up a simple forth-like system, after reading a brief howto here on hackernews:

https://github.com/skx/foth/

Here's the thread which has the barebones overview which inspired me:

https://news.ycombinator.com/item?id=13082825

I could have taken it further, but the implementation there is not "real" in the sense that there is no real return-stack, so you can't implement IF-statements using the lower-level primitives.

That said it is a good starting point, and I had some fun doing it. I'd guesstimate it is more of a single weekend project though, rather than longer.

Windows is supported. See https://github.com/rust-lang/rustc_codegen_cranelift/issues/....

> When this happens, it seems like it'll be possible to get the LLVM bits out of the bootstrap process and lead to a fully self-hosted Rust.

What do you mean by "when this happens"? GP's point is that this has already happened: the Cranelift backend is feature-complete from the perspective of the language [0], except for inline assembly and unwinding on panic. It was merged into the upstream compiler in 2020 [1], and a compiler built with only the Cranelift backend is perfectly capable of building another compiler. LLVM hasn't been a necessary component of the Rust compiler for quite some time.

[0] https://github.com/bjorn3/rustc_codegen_cranelift

[1] https://github.com/rust-lang/rust/pull/77975

Note that the Cranelift codegen will eventually become standard for debug builds to speed them up.

Maybe one day we'll have rustc b3 backend like what they did with Cranelift

Additionally, there is gcc codegen for rustc (https://github.com/rust-lang/rustc_codegen_gcc), which is not a compiler per se, but an alternative code generator, with more architectures supported and other nice things. It's also coming along, but there's still a lot of work to do there too. There's also Cranelift codegen (https://github.com/bjorn3/rustc_codegen_cranelift), which is designed to make debug builds faster, but this is not as exciting/useful as the other 2.

For the instant reloading, that's in Sycamore, so you should speak to its devs, but as for the alternative compiler backend, it's not my project, but it uses Cranelift and works pretty well! See https://github.com/bjorn3/rustc_codegen_cranelift for details.

The more immediate goal of "distribute the cranelift backend as a rustup component" has been making good progress and seems like it might happen relatively soon https://github.com/bjorn3/rustc_codegen_cranelift/milestone/...