Shrink ast::Attribute.

[nnethercote]

r? @ghost

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit 0d1133901da5599ad9f955041c4855ecc460de65 with merge bad7d1c65f1cb84b8cfebde01942c43777b59160...

[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

[nnethercote]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

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

[bors]

⌛ Trying commit a69032bdeb2941eeb468fb6f9db72ba6e0a73c1e with merge b15be6b3ef71de4bedb1f1eabeb93191f85dbec3...

[rustbot]

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 c1f0e3653fc959786724c92645d51f43491ec858 with merge 4c7727694361ebbb11914ea478f7ef88149135bb...

[bors]

☀️ Try build successful - checks-actions
Build commit: 4c7727694361ebbb11914ea478f7ef88149135bb (4c7727694361ebbb11914ea478f7ef88149135bb)

[rust-timer]

Queued 4c7727694361ebbb11914ea478f7ef88149135bb with parent e2b52ff, future comparison URL.

[rust-timer]

Finished benchmarking commit (4c7727694361ebbb11914ea478f7ef88149135bb): comparison url.

Instruction count

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

	mean1	max	count2
Regressions ❌ (primary)	0.9%	0.9%	2
Regressions ❌ (secondary)	0.2%	0.3%	9
Improvements ✅ (primary)	-0.6%	-1.6%	20
Improvements ✅ (secondary)	-1.0%	-1.5%	22
All ❌✅ (primary)	-0.5%	-1.6%	22

Max RSS (memory usage)

Results

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

	mean1	max	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	3.2%	4.1%	2
Improvements ✅ (primary)	-3.5%	-5.8%	27
Improvements ✅ (secondary)	-4.5%	-6.0%	30
All ❌✅ (primary)	-3.5%	-5.8%	27

Cycles

Results

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

	mean1	max	count2
Regressions ❌ (primary)	2.2%	2.5%	2
Regressions ❌ (secondary)	2.2%	2.2%	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.2%	2.5%	2

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]

Surprisingly good results on doc profiles, especially for max-rss. I don't know why doc profiles would be more sensitive to AST changes than other profilers. doc builds often use a lot more memory, too, e.g. max-rss (last two columns show the actual max-rss numbers):

Benchmark	Profile	Scenario	% Change	Significance Factor?	#99464	#100441
helloworld	doc	full	-5.80%	5.59x	244,436	230,252
helloworld	check	full	0.03%	0.02x	84,708	84,732

cc @jyn514

[jyn514]

I don't know why doc profiles would be more sensitive to AST changes than other profilers. doc builds often use a lot more memory, too, e.g. max-rss (last two columns show the actual max-rss numbers):

that doesn't surprise me too much - everything in https://doc.rust-lang.org/nightly/nightly-rustc/rustdoc/clean/types/index.html is basically a wrapper around rustc_ast or rustc_hir, and we duplicate a lot of stuff in DocContext that's already in TyCtxt.

Glad to see this improve the performance so much!

[nnethercote]

@bors r=petrochenkov

[bors]

📌 Commit b0e6d97087b1735ac94f071f815f85922bc33137 has been approved by petrochenkov

It is now in the queue for this repository.

[nnethercote]

@bors r-

[nnethercote]

Third time lucky:

@bors r=petrochenkov

[bors]

📌 Commit 85a6cd6 has been approved by petrochenkov

It is now in the queue for this repository.

[bors]

⌛ Testing commit 85a6cd6 with merge 14a459b...

[klensy]

There some ast trait that implemented for some structs with tokens. Should it be implemented for NormalAttr?

rust/compiler/rustc_ast/src/ast_traits.rs

Lines 131 to 162 in 8556e66

	macro_rules! impl_has_tokens {
	($($T:ty),+ $(,)?) => {
	$(
	impl HasTokens for $T {
	fn tokens(&self) -> Option<&LazyTokenStream> {
	self.tokens.as_ref()
	}
	fn tokens_mut(&mut self) -> Option<&mut Option<LazyTokenStream>> {
	Some(&mut self.tokens)
	}
	}
	)+
	};
	}
	macro_rules! impl_has_tokens_none {
	($($T:ty),+ $(,)?) => {
	$(
	impl HasTokens for $T {
	fn tokens(&self) -> Option<&LazyTokenStream> {
	None
	}
	fn tokens_mut(&mut self) -> Option<&mut Option<LazyTokenStream>> {
	None
	}
	}
	)+
	};
	}
	impl_has_tokens!(AssocItem, AttrItem, Block, Expr, ForeignItem, Item, Pat, Path, Ty, Visibility);
	impl_has_tokens_none!(Arm, ExprField, FieldDef, GenericParam, Param, PatField, Variant);

[nnethercote]

There some ast trait that implemented for some structs with tokens. Should it be implemented for NormalAttr?

It is covered here:

rust/compiler/rustc_ast/src/ast_traits.rs

Lines 212 to 229 in 8556e66

	impl HasTokens for Attribute {
	fn tokens(&self) -> Option<&LazyTokenStream> {
	match &self.kind {
	AttrKind::Normal(_, tokens) => tokens.as_ref(),
	kind @ AttrKind::DocComment(..) => {
	panic!("Called tokens on doc comment attr {:?}", kind)
	}
	}
	}
	fn tokens_mut(&mut self) -> Option<&mut Option<LazyTokenStream>> {
	Some(match &mut self.kind {
	AttrKind::Normal(_, tokens) => tokens,
	kind @ AttrKind::DocComment(..) => {
	panic!("Called tokens_mut on doc comment attr {:?}", kind)
	}
	})
	}
	}

[bors]

☀️ Test successful - checks-actions
Approved by: petrochenkov
Pushing 14a459b to master...

[rust-timer]

Finished benchmarking commit (14a459b): comparison url.

Instruction count

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

( )	mean1	max	count2
Regressions ❌ (primary)	0.6%	0.6%	1
Regressions ❌ (secondary)	0.2%	0.2%	1
Improvements ✅ (primary)	-0.6%	-1.4%	22
Improvements ✅ (secondary)	-1.0%	-1.5%	23
All ❌✅ (primary)	-0.5%	-1.4%	23

Max RSS (memory usage)

Results

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

( )	mean1	max	count2
Regressions ❌ (primary)	2.7%	2.7%	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-3.8%	-6.2%	24
Improvements ✅ (secondary)	-4.9%	-6.5%	27
All ❌✅ (primary)	-3.6%	-6.2%	25

Cycles

Results

• Primary benchmarks: ✅ relevant improvements found
• Secondary benchmarks: no relevant changes found

( )	mean1	max	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.7%	-3.5%	5
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.7%	-3.5%	5

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression

Footnotes

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

2. number of relevant changes ↩ ↩² ↩³