---
# System prepended metadata

title: Portable SIMD 2021-06-07 Meeting
tags: [Minutes, Portable SIMD]

---

# Portable SIMD 2021-06-07 Meeting

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

[Last Meeting] | [This Meeting's Chat] | [Next Meeting]

[Last Meeting]:  https://hackmd.io/tRDC_oOBRCeZrvK7ZMuXNQ
<!-- [This Meeting's Chat]:  -->
<!-- [Next Meeting]: -->

## Agenda

- Jacob: what did llvm-dev say?
    - whoops! No updates so far.
- Jubilee: stability annotations?
    - https://github.com/rust-lang/stdsimd/issues/70
    - We probably want to use a subtree: https://github.com/git/git/blob/master/contrib/subtree/git-subtree.txt
- bjorn3: cranelift?
    - No updates so far.
- scatter/gather?
    - draft on `feat/gather`!
- do we know more about what we want from trig?
    - not yet!
- to-nightly PR status?
- RFC draft status?
    - is this even required first?
- does documentation for a vector of pointers proposal exist?
    - no! :D
    - some information was discovered: LLVM supports `getelementptr` (aka `gep`) for vectors-of-pointers, so adding that capability to the compiler as simd intrinsics is possible if we want.
    - I wound up having to use casting pointers to ints and then back to pointers to get vectorized ops on pointers. That doesn't use `gep`, so may have weaker optimization.
    - Does that impose an implementation burden of any kind on e.g. cranelift?
    - Do we want to someday do this?
- do we have an example where rustc SIMD performance regresses relative to clang on x86-64, aarch64, or another architecture?

## Resolutions

0. It is prophesied that Jacob will remember to follow up on llvm-dev this time. :eyes: 
1. 