Shrink AST items

[nnethercote]

r? @ghost

[rustbot]

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

cc @camelid

Some changes occurred to the CTFE / Miri engine

cc @rust-lang/miri

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

Some changes occurred in src/tools/rustfmt

cc @rust-lang/rustfmt

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit c0a3752 with merge 7adcd665de8f8641e88434fadbfd09393b0bedee...

[bors]

💔 Test failed - checks-actions

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit 0e9ea62 with merge 0a2103a2fa8ce8fbf5460cc416160bbd7409a2b3...

[bors]

☀️ Try build successful - checks-actions
Build commit: 0a2103a2fa8ce8fbf5460cc416160bbd7409a2b3 (0a2103a2fa8ce8fbf5460cc416160bbd7409a2b3)

[rust-timer]

Queued 0a2103a2fa8ce8fbf5460cc416160bbd7409a2b3 with parent 1603a70, future comparison URL.

[rust-timer]

Finished benchmarking commit (0a2103a2fa8ce8fbf5460cc416160bbd7409a2b3): comparison url.

Instruction count

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

	mean1	max	count2
Regressions ❌ (primary)	N/A	N/A	0
Regressions ❌ (secondary)	N/A	N/A	0
Improvements ✅ (primary)	-0.2%	-0.3%	12
Improvements ✅ (secondary)	-0.6%	-1.0%	21
All ❌✅ (primary)	-0.2%	-0.3%	12

Max RSS (memory usage)

Results

• Primary benchmarks: mixed results
• Secondary benchmarks: ❌ relevant regressions found

	mean1	max	count2
Regressions ❌ (primary)	0.9%	0.9%	1
Regressions ❌ (secondary)	3.7%	8.6%	6
Improvements ✅ (primary)	-1.2%	-2.4%	4
Improvements ✅ (secondary)	-2.4%	-2.4%	1
All ❌✅ (primary)	-0.7%	-2.4%	5

Cycles

Results

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

	mean1	max	count2
Regressions ❌ (primary)	2.8%	2.8%	1
Regressions ❌ (secondary)	N/A	N/A	0
Improvements ✅ (primary)	N/A	N/A	0
Improvements ✅ (secondary)	-2.9%	-2.9%	1
All ❌✅ (primary)	2.8%	2.8%	1

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.

@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]

Pretty weak results here. I've subsequently made measurements that show Item is not that important. Expr, Ty, Path/PathSegment, and Attribute are all more important, so I will focus on them.

[nnethercote]

(Plus I put some of the early commits in #100391 and #100392.)