Lazy dominator tree construction in borrowck

[tmiasko]

Motivated by the observation that sometimes constructed dominator tree was never queried.

[rustbot]

r? @TaKO8Ki

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[tmiasko]

@bors try @rust-timer queue

[bors]

⌛ Trying commit fa8e7955ed59c56c77055e6c77e082eceeb8d970 with merge 69293dfb0c08c5062c97bca2ed1c755f046d6a99...

[bors]

☀️ Try build successful - checks-actions
Build commit: 69293dfb0c08c5062c97bca2ed1c755f046d6a99 (69293dfb0c08c5062c97bca2ed1c755f046d6a99)

[rust-timer]

Finished benchmarking commit (69293dfb0c08c5062c97bca2ed1c755f046d6a99): comparison URL.

Overall result: ✅ improvements - 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 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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.3%	[-0.6%, -0.2%]	33
Improvements ✅ (secondary)	-0.5%	[-0.8%, -0.2%]	10
All ❌✅ (primary)	-0.3%	[-0.6%, -0.2%]	33

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)	-4.3%	[-4.3%, -4.3%]	1
All ❌✅ (primary)	-	-	0

Cycles

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

[cjgillot]

@bors r+

[bors]

📌 Commit 7fe6857 has been approved by cjgillot

It is now in the queue for this repository.

[bors]

⌛ Testing commit 7fe6857 with merge 21f6839...

[bors]

☀️ Test successful - checks-actions
Approved by: cjgillot
Pushing 21f6839 to master...

[rust-timer]

Finished benchmarking commit (21f6839): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.4%	[-0.6%, -0.3%]	26
Improvements ✅ (secondary)	-0.7%	[-1.0%, -0.3%]	14
All ❌✅ (primary)	-0.4%	[-0.6%, -0.3%]	26

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)	2.5%	[2.5%, 2.5%]	1
Regressions ❌ (secondary)	5.0%	[3.1%, 6.9%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.2%	[-1.9%, -0.8%]	5
All ❌✅ (primary)	2.5%	[2.5%, 2.5%]	1

Cycles

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