Find the right lower bound region in the scenario of partial order relations

[chenyukang]

Fixes #104639

[rustbot]

Failed to set assignee to aliemjay: invalid assignee

Note: Only org members, users with write permissions, or people who have commented on the PR may be assigned.

[chenyukang]

@aliemjay

[aliemjay]

Looks good! Thanks!

[aliemjay]

cc @lqd @nikomatsakis
r? types

[aliemjay]

Oops, I missed that.

[aliemjay]

Suggested change

	*i == j || self.universal_region_relations.outlives(r1, r2)
	self.universal_region_relations.outlives(r2, r1)

The min_choice should be outlived by all others, not outlives all others. I'll be worried if we don't have tests that tripped for this.

There's also no need to check i == j because universal_region_relations is reflexive, so outlives(r1, r1) == true.

[chenyukang]

I just found a local test failed for my change:

async fn async_ret_impl_trait2<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a>
where
    'b: 'a,
{
    (a, b)
}

Will fix it.

[oli-obk]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 1fa6738fe198de3c058db1ffc346fc2866118b72 with merge 0993c8aa24cc1755371ba971db67c7da9162970e...

[oli-obk]

@bors try @rust-timer queue

[bors]

⌛ Trying commit b0d39c6 with merge f9109e9fb8f2d10b5ce3c3109963c05723d10c06...

[bors]

☀️ Try build successful - checks-actions
Build commit: f9109e9fb8f2d10b5ce3c3109963c05723d10c06 (f9109e9fb8f2d10b5ce3c3109963c05723d10c06)

[rust-timer]

Finished benchmarking commit (f9109e9fb8f2d10b5ce3c3109963c05723d10c06): 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-review -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)	0.6%	[0.4%, 0.9%]	7
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.9%	[-0.9%, -0.8%]	2
Improvements ✅ (secondary)	-2.1%	[-2.7%, -0.3%]	7
All ❌✅ (primary)	0.3%	[-0.9%, 0.9%]	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)	7.8%	[7.8%, 7.8%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
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)	-2.9%	[-3.6%, -2.1%]	10
All ❌✅ (primary)	-	-	0

[lqd]

The regressions above are likely current noise on these benchmarks -- and the O(N²) change here is probably fine at the low Ns we're expecting to see here ?

[bors]

⌛ Trying commit b0d39c6 with merge 97288fb87403b68dc2859cabca1c69afad7a3a89...

[compiler-errors]

Wait I didn't notice there was a perf run already oops

[bors]

☀️ Try build successful - checks-actions
Build commit: 97288fb87403b68dc2859cabca1c69afad7a3a89 (97288fb87403b68dc2859cabca1c69afad7a3a89)

[rust-timer]

Finished benchmarking commit (97288fb87403b68dc2859cabca1c69afad7a3a89): comparison URL.

Overall result: no relevant changes - no 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.

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

Instruction count

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

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)	-2.3%	[-2.3%, -2.3%]	1
Improvements ✅ (secondary)	-2.2%	[-3.5%, -0.8%]	3
All ❌✅ (primary)	-2.3%	[-2.3%, -2.3%]	1

Cycles

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

[rfcbot]

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

[oli-obk]

@bors r+ rollup=never (for bisectability)

[compiler-errors]

bors never seemed to register this

@bors r=oli-obk rollup=never

[bors]

📌 Commit b0d39c6 has been approved by oli-obk

It is now in the queue for this repository.

[bors]

⌛ Testing commit b0d39c6 with merge 939a3dd...

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 939a3dd to master...

[rust-timer]

Finished benchmarking commit (939a3dd): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

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

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)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.2%	[-3.2%, -3.2%]	1
All ❌✅ (primary)	-	-	0

Cycles

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