Reopen 91719

[shampoofactory]

Reopened #91719, which was closed inadvertently due to technical difficulties.

[rust-highfive]

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

Please see the contribution instructions for more information.

[workingjubilee]

r? @workingjubilee
Let's get the formalities out of the way as fast as possible.
@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[scottmcm]

Sorry, I forget this when I suggested the codegen test.

[workingjubilee]

@bors try

[bors]

⌛ Trying commit 0c13186 with merge 52b7c7ed6f087a5b756d1905d486240019ae4a29...

[bors]

☀️ Try build successful - checks-actions
Build commit: 52b7c7ed6f087a5b756d1905d486240019ae4a29 (52b7c7ed6f087a5b756d1905d486240019ae4a29)

[rust-timer]

Queued 52b7c7ed6f087a5b756d1905d486240019ae4a29 with parent 10913c0, future comparison URL.

[rust-timer]

Finished benchmarking commit (52b7c7ed6f087a5b756d1905d486240019ae4a29): comparison url.

Summary: This benchmark run shows 111 relevant improvements 🎉 but 37 relevant regressions 😿 to instruction counts.

• Arithmetic mean of relevant regressions: 0.5%
• Arithmetic mean of relevant improvements: -1.5%
• Arithmetic mean of all relevant changes: -1.0%
• Largest improvement in instruction counts: -6.9% on full builds of deeply-nested-async check
• Largest regression in instruction counts: 1.4% on incr-full builds of piston-image opt

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. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR led to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

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

[workingjubilee]

Excellent!

To quote myself again:
"That's even nicer than the last run. The highs aren't actually that much higher, but the dips are shallower and it's on average much better. It might be within random variance, but I suspect this actually neatly explains why what was once an optimization is now a regression: the Rust ABI was diverted down a path that LLVM did not focus much on optimizing in the next 5 versions, so as LLVM 14 is somewhat better at this than LLVM 13, likely LLVM 13 was better than LLVM 12, etc., all the way back to LLVM 9, when it was actually a win to take the other path."

@rustbot label: +perf-regression-triaged
@bors r+

[bors]

📌 Commit 0c13186 has been approved by workingjubilee

[bors]

⌛ Testing commit 0c13186 with merge b4bf56c...

[bors]

☀️ Test successful - checks-actions
Approved by: workingjubilee
Pushing b4bf56c to master...

[rust-timer]

Finished benchmarking commit (b4bf56c): comparison url.

Summary: This benchmark run shows 131 relevant improvements 🎉 but 28 relevant regressions 😿 to instruction counts.

• Arithmetic mean of relevant regressions: 0.5%
• Arithmetic mean of relevant improvements: -1.4%
• Arithmetic mean of all relevant changes: -1.0%
• Largest improvement in instruction counts: -6.9% on full builds of deeply-nested-async check
• Largest regression in instruction counts: 1.3% on incr-full builds of piston-image opt

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

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression