portable-simd VS swift-bridge

Jubilee and Caleb Zulawski for their tireless work on the portable SIMD project. It will land, some day, and when it does it's going to be an amazing boon for the project.

The portable SIMD project implements an as_simd() function for slices. The basics are that you get 3 slices and the middle one is a SIMD slice. It allows for fast aligned loads of the data, which could matter if your algorithm is becoming memory bound; it is also a convenient and safe abstraction. In my case, I actually have 2 vectors (say, x and y). I can take them apart using as_simd() like so:

Rust has generics and monomorphization. You can write the algorithm once and compile for multiple targets. rust-lang/portable-simd

This Rust issue [0] was the best short summary of what an SIMD Shuffle is I could find:

„A "shuffle", in SIMD terms, takes a SIMD vector (or possibly two vectors) and a pattern of source lane indexes (usually as an immediate), and then produces a new SIMD vector where the output is the source lane values in the pattern given.“

[0] https://github.com/rust-lang/portable-simd/issues/11

Yet by default it generates code which is only compatible with Pentium4 or newer. In fact lots of serious issues relate to older CPUs and rustc developers plan is to declare them closed when they would be able to drop i686 support (all AMD CPUs which support SSE2 support x86-64, too while Intel situation is mess).

The standard API crate for portable simd is at https://github.com/rust-lang/portable-simd, but using this requires nightly, which I don't want to do. I'd like to use a crate for simd that works on both x86_64 and wasm in stable rust. wide looks fine for this purpose. Are there any potentially better choices?

See: https://github.com/rust-lang/portable-simd

As for portable SIMD, there's relatively recent activity (last commit 20 days ago) on this repository: https://github.com/rust-lang/portable-simd

A bit late, but `swift-bridge` (https://github.com/chinedufn/swift-bridge) does this intelligently, and is probably what you're looking for.

4) Another route that I tried is to develop a simple terminal app using SwiftUI with a Xcode project to build that app + link against a Rust library compiled for iOS with the actual logic. I used swift-bridge for this and it works really well, to the point where I have a custom logger that you can simply use the print stuff to SwiftUI from Rust using the log crate. Once I have a bit more time, I will probably try figuring out how to clean this up a bit more.

Since Swift is your first target, I might recommend swift-bridge which can generate bindings for Rust async fns that Swift can call directly.

I'm working on getting my GUI crate (https://github.com/audulus/rui) working on iOS (https://github.com/audulus/rui-ios). Multitouch will be fun. Shout out to the excellent work in swift-bridge: https://github.com/chinedufn/swift-bridge.

So that class SwiftString was actually unused. I've removed it here https://github.com/chinedufn/swift-bridge/pull/33 .

Here's an example of a Rust library that exposes an async function that uses reqwest to make an API call, and a main.swift that calls that async function.

Have you tried Swift Bridge? https://github.com/chinedufn/swift-bridge