What does HackerNews think of rustc_codegen_cranelift?

Cranelift based backend for rustc

Language: Rust

#8 in Compiler
#2 in JavaScript
#25 in Rust
A Guide to Undefined Behavior in C and C++ (2010) | Aug 2023
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> 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 Cranelift-based Rust compiler is perfectly capable of bootstrapping another Rust compiler (with some config changes).

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

[1] https://github.com/rust-lang/rust/pull/77975
Vale's First Prototype for Immutable Region Borrowing | Jul 2023
> Vale-specific pre-optimizer, similar to Rust's Cranelift

I think this might instead be MIR, mid-level IR, there’s a good blog post here: https://blog.rust-lang.org/2016/04/19/MIR.html

Cranelift is a compiler backend, mainly focused on JIT, but theoretically could replace LLVM, there’s an alternative backend being worked on but has limitations: https://github.com/bjorn3/rustc_codegen_cranelift

Improving Rust compile times to enable adoption of memory safety | Feb 2023
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Cranelift is not used for debug builds by default. I think that's probably a goal (although I'm not actually 100% sure about that just because I'm not dialed into what the compiler team is doing). Even the OP mentions this:

> We were able to benchmark bjorn3's cranelift codegen backend on full crates as well as on the build dependencies specifically (since they're also built for cargo check builds, and are always built without optimizations): there were no issues, and it performed impressively. It's well on its way to becoming a viable alternative to the LLVM backend for debug builds.

And the Cranelift codegen backend itself is also clear about it not being ready yet: https://github.com/bjorn3/rustc_codegen_cranelift

(To be clear, I am super excited about using Cranelift for debug builds. I just want to clarify that it isn't actually used by default yet.)
Thoughts on what a next Rust compiler would do | Jan 2023
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maybe https://github.com/bjorn3/rustc_codegen_cranelift

https://old.reddit.com/r/rust/comments/107afei/cranelift_mol...
Thoughts on what a next Rust compiler would do | Jan 2023
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Bjorn3 for all their work on cranelift and working towards getting it to be a better debug compiler for rust.[1]

cwfitzgerald for wgpu. He took over as the head maintainer after kvark left Mozilla to go to Tesla.

winit maintainers, they're a core ecosystem crate but don't get that much support because windowing isn't flashy.

[1] https://github.com/bjorn3/rustc_codegen_cranelift
50 years of C, the good, the bad and the ugly [video] | Dec 2022
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There are some open issues and features like inline assembly that aren't supported, but a moderately complete backend exists now:

https://github.com/bjorn3/rustc_codegen_cranelift

The compiler frontend is already written in Rust.
How to speed up the Rust compiler in October 2022 | Oct 2022
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Yes, I guess?: Cranelift, which is a LLVM-like library written in Rust. This could be used for faster debug builds in the future. There's a Rust backend using Cranelift [2].

If you mean addressing the poor quality of LLVM IR directly, then I don't know.

[1]: https://github.com/bytecodealliance/wasmtime/blob/main/crane... [2]: https://github.com/bjorn3/rustc_codegen_cranelift
Adding a Rust compiler front end to GCC [video] | Jun 2022
As well as a cranelift backend https://github.com/bjorn3/rustc_codegen_cranelift
The Rust compiler has gotten faster again | Nov 2021
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A faster codegen backend for debug builds is in the works.

https://github.com/bjorn3/rustc_codegen_cranelift
Lang Jam: create a programming language in a weekend | Aug 2021
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There's a Cranelift backend, which is apparently faster at creating debug builds than LLVM: https://github.com/bjorn3/rustc_codegen_cranelift
Reducing Rust Incremental Compilation Times on macOS | Apr 2021
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There is work on integrating Cranelift into rustc (https://github.com/bjorn3/rustc_codegen_cranelift) so that rustc can compile to bytecode for the Cranelift JIT.
Are we game yet? – A guide to the Rust game development ecosystem | Feb 2021
Strictly speaking rustc has a dependency on LLVM, which is in C++, but you could use the rustc_codegen_cranelift backend [1] and get pretty much everything to be pure Rust. Unless you count the libc dependency, in which case, um, I guess you could use relibc [2]? And if you think relying on OS syscalls implemented in not-Rust is cheating, then you could just use Redox directly ;)

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

[2] https://github.com/redox-os/relibc