Revert #111753

[compiler-errors]

Reverts #111753, which was a perf regression. I had r+'d it but didn't catch that the perf results were negative.

r? @cjgillot

[compiler-errors]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 66e33b7 with merge 16ced9bd4388f2c9e0deac2b68547bae5cc509db...

[bors]

☀️ Try build successful - checks-actions
Build commit: 16ced9bd4388f2c9e0deac2b68547bae5cc509db (16ced9bd4388f2c9e0deac2b68547bae5cc509db)

[rust-timer]

Finished benchmarking commit (16ced9bd4388f2c9e0deac2b68547bae5cc509db): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

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 may lead 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-perf +perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.4%	[0.2%, 0.6%]	6
Regressions ❌ (secondary)	0.4%	[0.4%, 0.5%]	8
Improvements ✅ (primary)	-0.3%	[-0.4%, -0.2%]	3
Improvements ✅ (secondary)	-0.8%	[-1.0%, -0.7%]	4
All ❌✅ (primary)	0.2%	[-0.4%, 0.6%]	9

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.0%	[-3.0%, -3.0%]	1
All ❌✅ (primary)	-	-	0

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.7%	[-3.7%, -3.7%]	1
All ❌✅ (primary)	-	-	0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: missing data

[cjgillot]

Uh... Is this a regression too?

[compiler-errors]

Maybe someone from @rust-lang/wg-compiler-performance can help tease out what's noise and what's a regression.

[Kobzol]

It looks like it did actually revert some of the benchmarks (tt-muncher, tuple-stress [this one was green before, but just slightly], html5-ever). The big coercions regression before was probably just noise, because the benchmark has been quite noisy recently.

[cjgillot]

Should we close this PR, or do you still want to merge it?

[compiler-errors]

Seems like nobody particularly cares about this perf regression, so I'm gonna just close this.