Improve byte buffer iteration speed by 90%

[ejensen]

Overview

Improves the speed of comparing memory buffers by using an alternative to for in which is significantly slower when compiler optimizations are disabled - such as most unit test scenarios. SR-6983

Related Issues:

• This PR adds a similar speedup as Perceptual image precision + 90% speed improvement #628 but for the non-perceptual image comparison case
• Closes Precision checking algorithm is very slow #573 for the non-perceptual image comparison case

[ThePragmaticArt]

This seems to be a long time opened PR. We're in a bit of a situation right now where CI is executed on Intel, but local devices are Apple Silicon. The performance gain in this change is invaluable cost/time wise. Is there any reason this hasn't been merged in yet?

@stephencelis (maybe worth a chime in if there's a potential implementation issue)

[Kaspik]

@jflan-dd @mbrandonw @stephencelis Guys, could we please get any attention on this repo and merge those extremely great and useful PRs? 🙏🏼

[jflan-dd]

@Kaspik I wish I could help, but I'm not a maintainer on this repo. I wrote https://github.com/doordash-oss/swiftui-preview-snapshots which is a "plugin" for this repo, but it's purely a third party contribution.

[Kaspik]

@stephencelis And this one please.

[jaanus]

Just a +1 from me. I‘ve been suffering from the slowness of the non-perceptual UIImage snapshot tests byte buffer comparison, and identified that it is exactly this loop causing the slowness. And I can confirm that the fix in this PR does work for me as expected, making the comparison massively faster. I may have to fork the repo and include this fix until this gets resolved.

[mbrandonw]

Sorry for the late response, but this looks good to us. Will merge!

[mbrandonw]

Actually going to close this and re-open a PR with some small fixes and re-based on top of main.

[mbrandonw]

We just released this in 1.15.1.

[jaanus]

❤️ lovely, thank you.