---
# System prepended metadata

title: Portable SIMD 2020-09-21 Meeting
tags: [Minutes, Portable SIMD]

---

# Portable SIMD 2020-09-21 Meeting

###### tags: `Portable SIMD` `Minutes`

[This Week's Chat](https://rust-lang.zulipchat.com/#narrow/stream/257879-project-portable-simd/topic/2020-09-21.20meeting) | [Next Week](https://hackmd.io/a2vhyS0ZTtq1e7JkH2kabA?view)

## Summary

### Where does the code live?

- `rust-lang/stdarch` exists independently of `rust-lang/rust` for historical reasons. It has a lot of CI infra that we'd probably also need for `std::simd`.
- `rust-lang/rust` can be difficult to work on directly, we'd rather at least start externally.
- Complex CI infra might keep `std::simd` independent of `rust-lang/rust`. It means updating `std::simd` needs a PR to update the submodule.

### Announcement post

- We'd like to wait until we have the repo set up with a _Hello, SIMD!_ before we post the announcement.
- People _have opionions_ about SIMD so we're expecting interest.

### Nomenclature

- It's worth being accurate and accessible with the language we use when talking about SIMD.
- Do we call them _intrinsics_, _operations_, _intrinsic functions_?
- We'd like to develop some resources to help newcomers understand what SIMD is all about.

### Are we looking at length-agnostic APIs?

- OpenMP has `omp simd reduction` directives for vectorization hints.
- There's also [ARM SVE (Scalable Vector Extensions)](https://developer.arm.com/documentation/100891/0612/coding-considerations/using-sve-intrinsics-directly-in-your-c-code) but those probably won't be supported in Rust for a while because they use "magic" unsized types.

## Outcomes

1) Finish working over the announcement, it's not going out today. try to post it to rust-lang?
2) Build out a repo for std::simd, overwhelming preference is to have it outside rust-lang/rust for now.
3) Figure out our own project group repo and get some "Hello, SIMD!" intro on it. Scratch space: https://hackmd.io/T-cUNypRRUKGVBGlzr5fNA
4) finish bikeshedding on "what do we call intrinsics?"
5) address the packed_simd maintenance question
6) same time next week? Or in 2 weeks?