Make wrapping_neg() use wrapping_sub(), #[inline(always)]

[hkratz]

This is a follow-up change to the fix for #75598. It simplifies the implementation of wrapping_neg() for all integer types by just calling 0.wrapping_sub(self) and always inlines it. This leads to much less assembly code being emitted for opt-level≤1 and thus much better performance for debug-compiled code.

Background is this discussion on the internals forum.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @yaahc (or someone else) soon.

Please see the contribution instructions for more information.

[JohnTitor]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit a3fb1d6 with merge 21bb34363f449dc5907f72abf77c2b066ec467f5...

[bors]

☀️ Try build successful - checks-actions
Build commit: 21bb34363f449dc5907f72abf77c2b066ec467f5 (21bb34363f449dc5907f72abf77c2b066ec467f5)

[rust-timer]

Queued 21bb34363f449dc5907f72abf77c2b066ec467f5 with parent fd853c0, future comparison URL.

[rust-timer]

Finished benchmarking try commit (21bb34363f449dc5907f72abf77c2b066ec467f5): comparison url.

Summary: This benchmark run did not return any significant changes.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up.

@bors rollup=never
@rustbot label: +S-waiting-on-review -S-waiting-on-perf -perf-regression

[JohnTitor]

The perf results seem acceptable. The change makes sense to me, +1.

[hkratz]

@yaahc Could you please have a look?

[m-ou-se]

@bors r+

[bors]

📌 Commit a3fb1d6 has been approved by m-ou-se

[bors]

⌛ Testing commit a3fb1d6 with merge 7f3dc04...

[bors]

☀️ Test successful - checks-actions
Approved by: m-ou-se
Pushing 7f3dc04 to master...