Merge pull request #1165 from rylev/triage-2022-02-02

Add triage 2022-02-02

Author: Mark-Simulacrum

triage/2022-02-02.md

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+# 2022-02-02 Triage Log
+
+This was a relatively quiet week with regressions and improvements relatively equally each other out. The big exception is with a somewhat large regression in rustdoc which was needed for a large and important architectural change. This could lead to users see somewhat slower doc build times with more memory used especially in projects with large crate dependency graphs.
+
+Triage done by **@rylev**.
+Revision range: [c54dfee65126a0ac385d55389a316e89095a0713..1ea4851715893ee3f365a8ef09d47165e9a7864f](https://perf.rust-lang.org/?start=c54dfee65126a0ac385d55389a316e89095a0713&end=1ea4851715893ee3f365a8ef09d47165e9a7864f&absolute=false&stat=instructions%3Au)
+
+2 Regressions, 4 Improvements, 2 Mixed; 1 of them in rollups
+35 comparisons made in total
+
+#### Regressions
+
+rustdoc: Pre-calculate traits that are in scope for doc links [#88679](https://github.com/rust-lang/rust/issues/88679)
+- Average relevant regression: 5.4%
+- Largest regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=d502eda250d0090f4990cc6880c88b95a92b4818&end=788b1fe5b79a8b74215022f9df49b0eae68a50b9&stat=instructions:u): 9.1% on `full` builds of `regression-31157 doc`
+- All the regressions are localized to rustdoc and are quite substantial but exacerbated by an architectural issue which needs to be solved.
+- The regressions are well known and extensively discussed in the PR with the [next steps](https://github.com/rust-lang/rust/pull/88679#issuecomment-1021810724) being tracked in an issue.
+
+
+Store def_id_to_hir_id as variant in hir_owner. [#93373](https://github.com/rust-lang/rust/issues/93373)
+- Average relevant regression: 1.2%
+- Average relevant improvement: -0.3%
+- Largest regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=86f5e177bca8121e1edc9864023a8ea61acf9034&end=24b8bb13bff98bb747cd403b86596af43aceee78&stat=instructions:u): 5.5% on `incr-unchanged` builds of `match-stress-enum check`
+- This is the first commit (originally bundled with [#93301](https://github.com/rust-lang/rust/issues/93301)) of a larger PR ([#89278](https://github.com/rust-lang/rust/pull/89278)) which saw larger PR regressions than the two sub PRs combined.
+- A more detailed justification for this can be [found here](https://github.com/rust-lang/rust/pull/93373#issuecomment-1027962065), but in general this allows for even more incremental compilation and is thus worth the small immediate compilation performance penalty. 
+
+
+#### Improvements
+
+Fix the unsoundness in the `early_otherwise_branch` mir opt pass [#91840](https://github.com/rust-lang/rust/issues/91840)
+- Average relevant improvement: -1.1%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=788b1fe5b79a8b74215022f9df49b0eae68a50b9&end=a7f375789bab1a4e4a291c963081a8ca7d2b6bd7&stat=instructions:u): -6.9% on `full` builds of `deeply-nested-async check`
+
+
+Only traverse attrs once while checking for coherence override attributes [#93343](https://github.com/rust-lang/rust/issues/93343)
+- Average relevant improvement: -1.1%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=5ab502c6d308b0ccac8127c0464e432334755a60&end=312a7995e73e390646bc61920ffead7a640addc6&stat=instructions:u): -1.4% on `incr-full` builds of `stm32f4 check`
+
+
+Rollup of 10 pull requests [#93427](https://github.com/rust-lang/rust/issues/93427)
+- Average relevant improvement: -1.2%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=e0a55f4491a729bffc63b402ba903d90858c806b&end=6250d5a08cf0870d3655fa98b83718bc01ff6f45&stat=instructions:u): -1.9% on `full` builds of `ctfe-stress-4 doc`
+
+
+Disable drop range analysis [#93284](https://github.com/rust-lang/rust/issues/93284)
+- Average relevant improvement: -1.6%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=547f2ba06bc4aa93a375c54e1af3fd1216eeaf62&end=686663a49e57870c78a4cd047f23a44175fc67a4&stat=instructions:u): -2.0% on `full` builds of `await-call-tree check`
+
+
+#### Mixed
+
+Store hir_id_to_def_id in OwnerInfo. [#93301](https://github.com/rust-lang/rust/issues/93301)
+- Average relevant regression: 0.6%
+- Average relevant improvement: -0.5%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=a7f375789bab1a4e4a291c963081a8ca7d2b6bd7&end=6abb6385b2cb7249f67b9b3ce7522527767dd907&stat=instructions:u): -0.6% on `full` builds of `unused-warnings check`
+- Largest regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=a7f375789bab1a4e4a291c963081a8ca7d2b6bd7&end=6abb6385b2cb7249f67b9b3ce7522527767dd907&stat=instructions:u): 2.2% on `incr-unchanged` builds of `match-stress-enum check`
+- This is the first commit (originally bundled with [#93373](https://github.com/rust-lang/rust/issues/93373)) of a larger PR ([#89278](https://github.com/rust-lang/rust/pull/89278)) which saw larger PR regressions than the two sub PRs combined.
+
+
+Create `core::fmt::ArgumentV1` with generics instead of fn pointer [#90891](https://github.com/rust-lang/rust/issues/90891)
+- Average relevant regression: 1.2%
+- Average relevant improvement: -1.2%
+- Largest improvement in [instruction counts](https://perf.rust-lang.org/compare.html?start=08df8b81d6e723c66fee579d57d61dc60bc21fc1&end=e58e7b10e13595b4df1b105bfb9ad03c8dee7832&stat=instructions:u): -6.7% on `full` builds of `tokio-webpush-simple opt`
+- Largest regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=08df8b81d6e723c66fee579d57d61dc60bc21fc1&end=e58e7b10e13595b4df1b105bfb9ad03c8dee7832&stat=instructions:u): 2.1% on `full` builds of `keccak check`
+- The improvements outweigh the regressions considerably and this was [considered](https://github.com/rust-lang/rust/pull/90891#issuecomment-970851616) a fine trade off.
+
+
+#### Probably changed
+
+The following is a list of comparisons which *probably* represent real performance changes,
+but we're not 100% sure. Please move things from this category into the categories
+above for changes you think *are* definitely relevant and file an issue for each so that
+we can consider how to change our heuristics.
+
+
+
+#### Untriaged Pull Requests
+
+- [#93466 Make dead code check a query.](https://github.com/rust-lang/rust/pull/93466)
+- [#93288 Rollup of 8 pull requests](https://github.com/rust-lang/rust/pull/93288)
+- [#93138 Rollup of 17 pull requests](https://github.com/rust-lang/rust/pull/93138)
+- [#93095 Store a `Symbol` instead of an `Ident` in `AssocItem`](https://github.com/rust-lang/rust/pull/93095)
+- [#92896 Update some rustc dependencies to deduplicate them](https://github.com/rust-lang/rust/pull/92896)
+- [#92844 Rollup of 9 pull requests](https://github.com/rust-lang/rust/pull/92844)
+- [#92816 Remove deprecated LLVM-style inline assembly](https://github.com/rust-lang/rust/pull/92816)
+- [#92805 partially revertish `lazily "compute" anon const default substs`](https://github.com/rust-lang/rust/pull/92805)
+- [#92534 Hash `Ident` spans in all HIR structures](https://github.com/rust-lang/rust/pull/92534)
+- [#92356 Add {Add,Sub,Mul,Div,Rem,BitXor,BitOr,BitAnd}{,Assign}<$t> to Saturat…](https://github.com/rust-lang/rust/pull/92356)
+- [#92277 rustc_metadata: Stop passing `CrateMetadataRef` by reference (step 1)](https://github.com/rust-lang/rust/pull/92277)
+- [#92252 Update pulldown-cmark version to 0.9](https://github.com/rust-lang/rust/pull/92252)
+- [#92229 Do not display `~const Drop` in rustdoc](https://github.com/rust-lang/rust/pull/92229)
+- [#92227 Rustdoc: use `is_doc_hidden` method on more places](https://github.com/rust-lang/rust/pull/92227)
+- [#92149 Fix bad caching of `~const Drop` bounds](https://github.com/rust-lang/rust/pull/92149)
+- [#92135 Add `#[inline]` modifier to `TypeId::of`](https://github.com/rust-lang/rust/pull/92135)
+- [#92110 Backport LLVM changes to disable deferred inlining](https://github.com/rust-lang/rust/pull/92110)
+- [#92106 Rollup of 4 pull requests](https://github.com/rust-lang/rust/pull/92106)
+- [#92088 intra-doc: Use an enum to represent URL fragments](https://github.com/rust-lang/rust/pull/92088)
+- [#92064 Rollup of 7 pull requests](https://github.com/rust-lang/rust/pull/92064)
+- [#92062 Rollup of 7 pull requests](https://github.com/rust-lang/rust/pull/92062)
+- [#92041 Remove 'speculative evaluation' of predicates](https://github.com/rust-lang/rust/pull/92041)
+- [#92003 Rollup of 7 pull requests](https://github.com/rust-lang/rust/pull/92003)
+- [#91996 Rollup of 6 pull requests](https://github.com/rust-lang/rust/pull/91996)
+- [#91959 Rollup of 7 pull requests](https://github.com/rust-lang/rust/pull/91959)
+- [#91924 Fully serialize AdtDef](https://github.com/rust-lang/rust/pull/91924)
+- [#91900 rustdoc: make `--passes` and `--no-defaults` have no effect](https://github.com/rust-lang/rust/pull/91900)
+- [#91844 Eliminate `ObligationCauseData`](https://github.com/rust-lang/rust/pull/91844)
+- [#91841 Rollup of 5 pull requests](https://github.com/rust-lang/rust/pull/91841)