[naga msl-out] Implement atomicCompareExchangeWeak for MSL backend

[AsherJingkongChen]

Connections

Fixes #5257 and #4364 (partially).
Closes #5675.

Description

Implement atomicCompareExchangeWeak for MSL (Metal) backend.

Please see Metal Specification 2024-06-06, Page 249 for support details.

Testing

I enabled and validated 2 snapshots for Metal.

Checklist

• Run cargo fmt.
• Run cargo clippy. If applicable, add:
  • --target wasm32-unknown-unknown
  • --target wasm32-unknown-emscripten
• Run cargo xtask test to run tests.
• Add change to CHANGELOG.md. See simple instructions inside file.

[jimblandy]

See also #5675

[AsherJingkongChen]

See also #5675

@jimblandy I understand that @9291Sam opened another similar PR, but the progress seems a bit slow. Since this branch is for my own project, I was hoping for quicker updates. That's why I decided to contribute.

[jimblandy]

@jimblandy I understand that @9291Sam opened another similar PR, but the progress seems a bit slow. Since this branch is for my own project, I was hoping for quicker updates. That's why I decided to contribute.

Oh, definitely. I think we should probably review this PR instead. I just wanted to have the linkage there so that people could find the relationship if they wanted.

[AsherJingkongChen]

@jimblandy I understand that @9291Sam opened another similar PR, but the progress seems a bit slow. Since this branch is for my own project, I was hoping for quicker updates. That's why I decided to contribute.

Oh, definitely. I think we should probably review this PR instead. I just wanted to have the linkage there so that people could find the relationship if they wanted.

@jimblandy I understand. Thank you.

[teoxoy]

Looks good, thanks!

[teoxoy]

@AsherJingkongChen this needs a rebase + updating the msl snapshots due to #6285.

[AsherJingkongChen]

@teoxoy I had not squashed commits, would it matter? I see it was auto-squashed.

[teoxoy]

I squashed them when I merged the PR (see bf33e48).