Cache hir_owner_nodes in ParentHirIterator.

[cjgillot]

Lint level computation may traverse deep HIR trees using that iterator. This calls hir_owner_nodes many times for the same HIR owner, which is wasterful.

This PR caches the value to allow a more efficient iteration scheme.

r? ghost for perf

[cjgillot]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 0184c6f with merge 0599355...

[bors]

☀️ Try build successful - checks-actions
Build commit: 0599355 (059935563ef543a242aa9664c8fd94a43791ed94)

[rust-timer]

Finished benchmarking commit (0599355): 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)	-0.4%	[-1.0%, -0.2%]	14
Improvements ✅ (secondary)	-0.1%	[-0.1%, -0.1%]	1
All ❌✅ (primary)	-0.4%	[-1.0%, -0.2%]	14

Max RSS (memory usage)

Results (primary -0.8%, secondary -1.8%)

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)	-0.8%	[-0.8%, -0.8%]	1
Improvements ✅ (secondary)	-1.8%	[-2.3%, -1.4%]	7
All ❌✅ (primary)	-0.8%	[-0.8%, -0.8%]	1

Cycles

Results (primary -2.1%, secondary -1.3%)

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)	0.5%	[0.4%, 0.5%]	2
Improvements ✅ (primary)	-2.1%	[-2.1%, -2.1%]	1
Improvements ✅ (secondary)	-2.0%	[-2.3%, -1.6%]	5
All ❌✅ (primary)	-2.1%	[-2.1%, -2.1%]	1

Binary size

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

Bootstrap: 697.348s -> 697.89s (0.08%)
Artifact size: 328.28 MiB -> 328.29 MiB (0.00%)

[cjgillot]

r? compiler

[fmease]

Thanks!
@bors r+

[bors]

📌 Commit 0184c6f has been approved by fmease

It is now in the queue for this repository.

[bors]

⌛ Testing commit 0184c6f with merge b1de36f...

[bors]

☀️ Test successful - checks-actions
Approved by: fmease
Pushing b1de36f to master...

[rust-timer]

Finished benchmarking commit (b1de36f): 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)	-0.3%	[-1.0%, -0.2%]	16
Improvements ✅ (secondary)	-0.1%	[-0.1%, -0.1%]	3
All ❌✅ (primary)	-0.3%	[-1.0%, -0.2%]	16

Max RSS (memory usage)

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

Cycles

Results (primary 2.6%)

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)	2.6%	[2.6%, 2.6%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.6%	[2.6%, 2.6%]	1

Binary size

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

Bootstrap: 699.119s -> 700.046s (0.13%)
Artifact size: 328.36 MiB -> 328.35 MiB (-0.00%)