[EXPERIMENT] Fewer ast boxes

[nnethercote]

No description provided.

[nnethercote]

@bors try @rust-timer queue

[rust-log-analyzer]

The job aarch64-gnu-llvm-21-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

   Compiling rustc_ty_utils v0.0.0 (/checkout/compiler/rustc_ty_utils)
error[E0308]: mismatched types
    --> compiler/rustc_parse/src/parser/tests.rs:2229:5
     |
2227 |   ) -> PResult<'_, Option<Box<ast::Item>>> {
     |        ----------------------------------- expected `Result<Option<std::boxed::Box<rustc_ast::Item>>, Diag<'_>>` because of return type
2228 |       // njn: ?
2229 | /     unwrap_or_emit_fatal(new_parser_from_source_str(psess, name, source, StripTokens::Nothing))
2230 | |         .parse_item(ForceCollect::No, AllowConstBlockItems::Yes)
     | |________________________________________________________________^ expected `Result<Option<Box<Item>>, Diag<'_>>`, found `Result<Option<Item>, Diag<'_>>`
     |
     = note: expected enum `Result<Option<std::boxed::Box<Item>>, Diag<'_>>`
                found enum `Result<Option<Item>, Diag<'_>>`

error[E0308]: mismatched types
    --> compiler/rustc_parse/src/parser/tests.rs:2246:5
     |
2244 |   fn string_to_item(source_str: String) -> Option<Box<ast::Item>> {
     |                                            ---------------------- expected `Option<std::boxed::Box<rustc_ast::Item>>` because of return type
2245 |       // njn: ?
2246 | /     with_error_checking_parse(source_str, &ParseSess::new(), |p| {
2247 | |         p.parse_item(ForceCollect::No, AllowConstBlockItems::Yes)
2248 | |     })
     | |______^ expected `Option<Box<Item>>`, found `Option<Item>`
     |
     = note: expected enum `Option<std::boxed::Box<Item>>`
                found enum `Option<Item>`

[RUSTC-TIMING] rustc_ty_utils test:true 2.909

[rust-bors]

☀️ Try build successful (CI)
Build commit: bab0c1e (bab0c1eb7e75290cf95b2efb244fc6c05c6aace4)
Base parent: da80ed0 (da80ed0708a09dc096c184345d6eb42cbcd50a1e)

[rust-timer]

Finished benchmarking commit (bab0c1e): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never rustc-perf
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	1.0%	[0.2%, 1.6%]	15
Regressions ❌ (secondary)	0.9%	[0.2%, 1.3%]	13
Improvements ✅ (primary)	-0.3%	[-0.3%, -0.3%]	1
Improvements ✅ (secondary)	-0.6%	[-1.6%, -0.2%]	21
All ❌✅ (primary)	0.9%	[-0.3%, 1.6%]	16

Max RSS (memory usage)

Results (primary 1.0%, secondary 4.4%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	1.0%	[0.5%, 1.6%]	25
Regressions ❌ (secondary)	4.4%	[0.6%, 11.4%]	17
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.0%	[0.5%, 1.6%]	25

Cycles

Results (primary 2.5%, secondary 2.1%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	2.5%	[2.1%, 2.8%]	3
Regressions ❌ (secondary)	4.2%	[2.4%, 8.2%]	5
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.0%	[-3.5%, -2.5%]	2
All ❌✅ (primary)	2.5%	[2.1%, 2.8%]	3

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 491.202s -> 489.983s (-0.25%)
Artifact size: 389.32 MiB -> 389.40 MiB (0.02%)