Files
rust/tests
Jonathan Brouwer 0f950ce670 Rollup merge of #156413 - fmease:rustdoc-ltd-improvs, r=GuillaumeGomez
rustdoc: Correctness & perf improvements to link-to-definition

Rewrite the way we resolve type-dependent paths (incl. method calls) in `SpanMapVisitor`. Instead of trying to (re)find the enclosing body owner each time we encounter such a node, potentially calling `typeck_body` several times per body, keep track of the "active" `BodyId` in the visitor and cache the corresponding `TypeckResults`. The "active" `BodyId` is updated in `visit_nested_body` (add) and in `visit_item` (remove).

This fixes a class of ICEs where we tried to look up the definition of type-relative paths located in non-body items nested in bodies, in the overarching body which is never correct. rustdoc@main has a hack to fix this issue for paths specifically found in assoc types in impls.

Fixes rust-lang/rust#147882. Fixes rust-lang/rust#147057. Fixes rust-lang/rust#155327. Fixes rust-lang/rust#149089. Fixes rust-lang/rust#150153. Fixes rust-lang/rust#156418.
Supersedes rust-lang/rust#147911.

---

`--generate-link-to-definition` is not enabled by default, so we can't perf this as is. Instead, I'm benching them against PR rust-lang/rust#156348 in PR https://github.com/rust-lang/rust/pull/156355 using the same parent commit for the try-builds. For context, LTD is *extremely* costly as the perf run for the baseline PR shows: https://github.com/rust-lang/rust/pull/156348#issuecomment-4411427326.

"Absolute results": https://github.com/rust-lang/rust/pull/156355#issuecomment-4421922342.
"Relative results": [https://perf.rust-lang.org/compare.html?...](https://perf.rust-lang.org/compare.html?start=68c2bff6cb08a87e59246064a6a9f37098e22c3f&end=78d15de5525370011388c8f63847e873c4de14ed&stat=instructions%3Au).

Excerpt of the relative results:

Primary:

Benchmark | Profile | Scenario | Backend | Target | % Change | Significance Threshold | Significance Factor
---|---|---|---|---|---|---|---
nalgebra-0.33.0 | doc | full | llvm | x64 | -5.82% | 0.20% | 29.09x
diesel-2.2.10 | doc | full | llvm | x64 | -3.41% | 0.20% | 17.05x
image-0.25.6 | doc | full | llvm | x64 | -2.03% | 0.20% | 10.16x
regex-automata-0.4.8 | doc | full | llvm | x64 | -1.94% | 0.20% | 9.71x
cargo-0.87.1 | doc | full | llvm | x64 | -1.64% | 0.20% | 8.21x
clap_derive-4.5.32 | doc | full | llvm | x64 | -1.63% | 0.20% | 8.14x
cranelift-codegen-0.119.0 | doc | full | llvm | x64 | -1.48% | 0.20% | 7.41x
syn-2.0.101 | doc | full | llvm | x64 | -1.07% | 0.20% | 5.35x
ripgrep-14.1.1 | doc | full | llvm | x64 | -0.96% | 0.20% | 4.78x
stm32f4-0.15.1 | doc | full | llvm | x64 | -0.80% | 0.20% | 4.01x
serde-1.0.219 | doc | full | llvm | x64 | -0.67% | 0.20% | 3.33x
hyper-1.6.0 | doc | full | llvm | x64 | -0.66% | 0.20% | 3.30x
eza-0.21.2 | doc | full | llvm | x64 | -0.55% | 0.20% | 2.74x
unicode-normalization-0.1.24 | doc | full | llvm | x64 | -0.49% | 0.20% | 2.45x
serde_derive-1.0.219 | doc | full | llvm | x64 | -0.45% | 0.20% | 2.26x
typenum-1.18.0 | doc | full | llvm | x64 | -0.42% | 0.20% | 2.08x
bitmaps-3.2.1 | doc | full | llvm | x64 | -0.32% | 0.20% | 1.61x

Secondary:

Benchmark | Profile | Scenario | Backend | Target | % Change | Significance Threshold | Significance Factor
---|---|---|---|---|---|---|---
deep-vector | doc | full | llvm | x64 | -23.96% | 0.20% | 119.78x
large-workspace | doc | full | llvm | x64 | -2.16% | 0.20% | 10.81x
deeply-nested-multi | doc | full | llvm | x64 | -1.35% | 0.20% | 6.75x
serde-1.0.219-threads4 | doc | full | llvm | x64 | -0.67% | 0.20% | 3.33x
wg-grammar | doc | full | llvm | x64 | -0.32% | 0.20% | 1.62x
tt-muncher | opt | full | llvm | x64 | -0.31% | 0.20% | 1.56x

nalgebra-0.33.0:

Query/Function | Time (%) | Time (s) | Time delta | Executions | Executions delta | Hits | Hits delta
---|---|---|---|---|---|---|---
Totals | 109.57% | 2.185 | -0.138 (-5.9%) | 1614146 | -5602 (-0.3%) | 16983840 | -1436455 (-7.8%)
typeck_root | 15.75% | 0.344 | -0.105 (-23.4%) | 1704 | -954 (-35.9%) | 393 | -6758 (-94.5%)
...|...|...|...|...|...|...|...
2026-05-14 00:35:38 +02:00
..