Use AttrVec more

[nnethercote]

In some places we use Vec<Attribute> and some places we use
ThinVec<Attribute> (a.k.a. AttrVec). This results in various points
where we have to convert between Vec and ThinVec.

This commit changes the places that use Vec<Attribute> to use
AttrVec. A lot of this is mechanical and boring, but there are
some interesting parts:

• It adds a few new methods to ThinVec.
• It implements MapInPlace for ThinVec, and introduces a macro to
  avoid the repetition of this trait for Vec, SmallVec, and
  ThinVec.

Overall, it makes the code a little nicer, and has little effect on
performance. But it is a precursor to removing
rustc_data_structures::ThinVec and replacing it with
thin_vec::ThinVec, which is implemented more efficiently.

r? @spastorino

[rustbot]

Some changes occurred in src/tools/rustfmt

cc @rust-lang/rustfmt

Some changes occurred in src/librustdoc/clean/types.rs

cc @camelid

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit 10127a2e4f63aac6abbfe354a60bca49e700b4b5 with merge ea19f197d57a419f4310951e073202e05bbe3615...

[nnethercote]

rustc exited with signal: 4 (SIGILL) (core dumped)

SIGILL here too? Is this from my changes (I haven't touched any unsafe code, or done anything unusual) or am I hitting some pre-existing problem? #100669, which cuts this PR back even more, will hopefully indicate one way or the other.

[bors]

☀️ Try build successful - checks-actions
Build commit: ea19f197d57a419f4310951e073202e05bbe3615 (ea19f197d57a419f4310951e073202e05bbe3615)

[rust-timer]

Queued ea19f197d57a419f4310951e073202e05bbe3615 with parent 86c6ebe, future comparison URL.

[rust-timer]

Finished benchmarking commit (ea19f197d57a419f4310951e073202e05bbe3615): comparison url.

Instruction count

• Primary benchmarks: mixed results
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	0.4%	1.0%	5
Regressions ❌ (secondary)	0.6%	1.1%	14
Improvements ✅ (primary)	-0.6%	-0.9%	4
Improvements ✅ (secondary)	-0.5%	-0.9%	21
All ❌✅ (primary)	-0.0%	1.0%	9

Max RSS (memory usage)

Results

• Primary benchmarks: mixed results
• Secondary benchmarks: ✅ relevant improvements found

	mean1	max	count2
Regressions ❌ (primary)	2.5%	2.5%	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.9%	-1.2%	2
Improvements ✅ (secondary)	-2.3%	-3.2%	5
All ❌✅ (primary)	0.2%	2.5%	3

Cycles

Results

• Primary benchmarks: ❌ relevant regressions found
• Secondary benchmarks: no relevant changes found

	mean1	max	count2
Regressions ❌ (primary)	6.1%	14.5%	3
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	6.1%	14.5%	3

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 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

Footnotes

1. the arithmetic mean of the percent change ↩ ↩² ↩³

2. number of relevant changes ↩ ↩² ↩³

[nnethercote]

@spastorino: you've already reviewed the first three commits in #100669, so only the fourth commit needs reviewing. Thanks!

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit ae79c3d4a81f3afec7ed78e756603011982eda7f with merge 7fa2c81cd586f461cc05f8a9268da92fc3a8c1b0...

[bors]

☀️ Try build successful - checks-actions
Build commit: 7fa2c81cd586f461cc05f8a9268da92fc3a8c1b0 (7fa2c81cd586f461cc05f8a9268da92fc3a8c1b0)

[rust-timer]

Queued 7fa2c81cd586f461cc05f8a9268da92fc3a8c1b0 with parent 9c20b2a, future comparison URL.

[rust-timer]

Finished benchmarking commit (7fa2c81cd586f461cc05f8a9268da92fc3a8c1b0): comparison url.

Instruction count

• Primary benchmarks: mixed results
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	0.7%	1.0%	3
Regressions ❌ (secondary)	0.6%	0.8%	10
Improvements ✅ (primary)	-0.6%	-1.0%	4
Improvements ✅ (secondary)	-0.5%	-1.0%	23
All ❌✅ (primary)	-0.1%	1.0%	7

Max RSS (memory usage)

Results

• Primary benchmarks: ✅ relevant improvements found
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.3%	2.4%	4
Improvements ✅ (primary)	-1.7%	-3.4%	5
Improvements ✅ (secondary)	-1.9%	-2.8%	7
All ❌✅ (primary)	-1.7%	-3.4%	5

Cycles

Results

• Primary benchmarks: no relevant changes found
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.9%	2.9%	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.3%	-2.6%	6
All ❌✅ (primary)	-	-	0

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 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

Footnotes

1. the arithmetic mean of the percent change ↩ ↩² ↩³

2. number of relevant changes ↩ ↩² ↩³

[spastorino]

@nnethercote r=me after rebasing

[nnethercote]

I have rebased. Although this is very close to performance-neutral, I will leave it as rollup=never because it has enough of an effect on performance (with improvements and regressions balancing out) that it shouldn't be part of a rollup.

@bors r=spastorino

[bors]

📌 Commit 9bd705836a272e21e2fbc4e95b5ec39906c9abb0 has been approved by spastorino

It is now in the queue for this repository.

[bors]

☔ The latest upstream changes (presumably #100564) made this pull request unmergeable. Please resolve the merge conflicts.

[nnethercote]

Rebased.

@bors r=spastorino

[bors]

📌 Commit 619b8ab has been approved by spastorino

It is now in the queue for this repository.

[bors]

⌛ Testing commit 619b8ab with merge 3ce46b7...

[bors]

☀️ Test successful - checks-actions
Approved by: spastorino
Pushing 3ce46b7 to master...

[rust-timer]

Finished benchmarking commit (3ce46b7): comparison url.

Instruction count

• Primary benchmarks: mixed results
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	0.6%	1.0%	2
Regressions ❌ (secondary)	0.6%	1.3%	8
Improvements ✅ (primary)	-0.3%	-0.4%	7
Improvements ✅ (secondary)	-0.5%	-1.2%	15
All ❌✅ (primary)	-0.1%	1.0%	9

Max RSS (memory usage)

Results

• Primary benchmarks: ✅ relevant improvements found
• Secondary benchmarks: mixed results

	mean1	max	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.7%	4.2%	8
Improvements ✅ (primary)	-2.0%	-3.9%	4
Improvements ✅ (secondary)	-1.7%	-2.2%	4
All ❌✅ (primary)	-2.0%	-3.9%	4

Cycles

Results

• Primary benchmarks: ❌ relevant regression found
• Secondary benchmarks: ❌ relevant regression found

	mean1	max	count2
Regressions ❌ (primary)	2.4%	2.4%	1
Regressions ❌ (secondary)	2.5%	2.5%	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.4%	2.4%	1

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
cc @rust-lang/wg-compiler-performance

Footnotes

1. the arithmetic mean of the percent change ↩ ↩² ↩³

2. number of relevant changes ↩ ↩² ↩³

[nnethercote]

As seen above, there are a few small wins and losses here, which balance each other out, and the net effect is perf-neutral.

@rustbot label: +perf-regression-triaged