Add triage for this week

triage/2022-07-05.md

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+# 2022-07-05 Triage Log
+
+Overall the week is a small improvement on average, with some benchmarks
+(particularly in the primary category) showing significant improvements due to
+the enablement of MIR inlining in
+[#91743](https://github.com/rust-lang/rust/pull/91743). Inlining promises to
+improve the quality of our generated LLVM IR and make other optimizations more
+worthwhile, so it's great to see these early results already being quite
+impactful.
+
+Triage done by **@simulacrum**.
+Revision range: [baf382e63c023259fa1f9042f8f479f183ca6ed3..880646ca9c6dc21e04efe2f1940369a45b71ff2d](https://perf.rust-lang.org/?start=baf382e63c023259fa1f9042f8f479f183ca6ed3&end=880646ca9c6dc21e04efe2f1940369a45b71ff2d&absolute=false&stat=instructions%3Au)
+
+**Summary**:
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 1.9% | 11.9% | 111   |
+| Regressions 😿 <br /> (secondary) | 3.4% | 11.9% | 106   |
+| Improvements 🎉 <br /> (primary) | -2.8% | -9.7% | 105   |
+| Improvements 🎉 <br /> (secondary) | -4.4% | -16.8% | 97    |
+| All 😿🎉 (primary) | -0.4% | 11.9% | 216   |
+
+
+3 Regressions, 6 Improvements, 6 Mixed; 4 of them in rollups
+46 artifact comparisons made in total
+
+#### Regressions
+
+Fix FFI-unwind unsoundness with mixed panic mode [#97235](https://github.com/rust-lang/rust/pull/97235)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=0075bb4fad68e64b6d1be06bf2db366c30bc75e1&end=6a1092056441652fe5fe5c5b422644951e6b99ce&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.5% | 1.2% | 86    |
+| Regressions 😿 <br /> (secondary) | 0.9% | 2.5% | 36    |
+| Improvements 🎉 <br /> (primary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (secondary) | N/A  | N/A | 0     |
+| All 😿🎉 (primary) | 0.5% | 1.2% | 86    |
+
+PR author notes this added a new query for each MIR body, so this is an
+expected regression, and given the soundness fix is not too large to need
+further investigation.
+
+Rollup of 5 pull requests [#98874](https://github.com/rust-lang/rust/pull/98874)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=a5c6a48aee84215a9200dfa1c4c6ad88f5721f56&end=9c9ae85a4773be3c1e33717e4fa9759b4ce020ef&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.6% | 0.9% | 13    |
+| Regressions 😿 <br /> (secondary) | 1.4% | 2.4% | 12    |
+| Improvements 🎉 <br /> (primary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (secondary) | N/A  | N/A | 0     |
+| All 😿🎉 (primary) | 0.6% | 0.9% | 13    |
+
+Some possibly real, though small, regressions. Unclear cause; rollup doesn't
+obviously contain any sensitive PRs.
+
+Rollup of 8 pull requests [#98904](https://github.com/rust-lang/rust/pull/98904)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=27eb6d7018e397cf98d51c205e3576951d766323&end=e1d1848cc60a407d06f90fd16877a19bed6edd9b&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.7% | 0.9% | 8     |
+| Regressions 😿 <br /> (secondary) | 1.1% | 2.3% | 16    |
+| Improvements 🎉 <br /> (primary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (secondary) | N/A  | N/A | 0     |
+| All 😿🎉 (primary) | 0.7% | 0.9% | 8     |
+
+Interestingly, regressions here are remarkably similar to those in #98874
+(previous rollup in this list). Not seeing an obvious connection between the PRs
+in the two rollups, though.
+
+#### Improvements
+
+proc_macro/bridge: stop using a remote object handle for proc_macro Punct and Group [#98188](https://github.com/rust-lang/rust/pull/98188)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=00ebeb87ac87a492bd59ace6bd43d6ad1629ca4e&end=94e93749ab00539a11e90426ea87382c433530a8&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | -0.5% | -1.4% | 15    |
+| Improvements 🎉 <br /> (secondary) | -1.6% | -5.0% | 16    |
+| All 😿🎉 (primary) | -0.5% | -1.4% | 15    |
+
+
+Update `smallvec` to 1.8.1. [#98558](https://github.com/rust-lang/rust/pull/98558)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=493c960a3e6cdd2e2fbe8b6ea130fadea05f1ab0&end=66c83ffca1512ed76f9445ec7f7280f768ef71c4&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (secondary) | -1.7% | -2.4% | 9     |
+| All 😿🎉 (primary) | N/A  | N/A | 0     |
+
+
+CTFE interning: don't walk allocations that don't need it [#97585](https://github.com/rust-lang/rust/pull/97585)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=6a1092056441652fe5fe5c5b422644951e6b99ce&end=750d6f85459356db4838dc06db8b19406e1ed31a&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | -1.0% | -1.0% | 2     |
+| Improvements 🎉 <br /> (secondary) | -2.5% | -9.3% | 32    |
+| All 😿🎉 (primary) | -1.0% | -1.0% | 2     |
+
+
+Optimize `Vec::insert` for the case where `index == len`. [#98755](https://github.com/rust-lang/rust/pull/98755)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=ada8c80bedb713b320af00aacab97d01d9cb5933&end=f99f9e48ed77a99747c6d07b42fdfe500f1a7de0&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | -0.4% | -1.0% | 8     |
+| Improvements 🎉 <br /> (secondary) | -1.2% | -2.4% | 13    |
+| All 😿🎉 (primary) | -0.4% | -1.0% | 8     |
+
+
+fully move dropck to mir [#98641](https://github.com/rust-lang/rust/pull/98641)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=9c9ae85a4773be3c1e33717e4fa9759b4ce020ef&end=a3beeaa84da241f35888338ded6659938206ff13&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.5% | 0.7% | 2     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | -0.7% | -2.4% | 34    |
+| Improvements 🎉 <br /> (secondary) | -0.8% | -2.1% | 22    |
+| All 😿🎉 (primary) | -0.7% | -2.4% | 36    |
+
+
+interpret: track place alignment together with the type, not the value [#98846](https://github.com/rust-lang/rust/pull/98846)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=e1d1848cc60a407d06f90fd16877a19bed6edd9b&end=4008dd8c6d92a0b81528fd138c6130d784e5958e&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (primary) | -0.7% | -0.9% | 8     |
+| Improvements 🎉 <br /> (secondary) | -1.2% | -2.3% | 13    |
+| All 😿🎉 (primary) | -0.7% | -0.9% | 8     |
+
+
+#### Mixed
+
+Rollup of 9 pull requests [#98612](https://github.com/rust-lang/rust/pull/98612)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=baf382e63c023259fa1f9042f8f479f183ca6ed3&end=00ebeb87ac87a492bd59ace6bd43d6ad1629ca4e&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.7% | 1.0% | 5     |
+| Regressions 😿 <br /> (secondary) | 5.2% | 9.9% | 6     |
+| Improvements 🎉 <br /> (primary) | -1.0% | -1.1% | 2     |
+| Improvements 🎉 <br /> (secondary) | -0.8% | -2.4% | 22    |
+| All 😿🎉 (primary) | 0.2% | -1.1% | 7     |
+
+
+Rollup of 7 pull requests [#98656](https://github.com/rust-lang/rust/pull/98656)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=116edb6800ea1d6615578e7f65366ae65364b3d8&end=493c960a3e6cdd2e2fbe8b6ea130fadea05f1ab0&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 1.4% | 11.3% | 131   |
+| Regressions 😿 <br /> (secondary) | 3.5% | 11.2% | 73    |
+| Improvements 🎉 <br /> (primary) | N/A  | N/A | 0     |
+| Improvements 🎉 <br /> (secondary) | -2.2% | -3.1% | 8     |
+| All 😿🎉 (primary) | 1.4% | 11.3% | 131   |
+
+Asked for further investigation on the PR, noting
+[#98277](https://github.com/rust-lang/rust/pull/98277) as a possible cause.
+
+move MIR syntax into a dedicated file and ping some people whenever it changes [#98649](https://github.com/rust-lang/rust/pull/98649)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=5d3c6d6c83edc4ef245e77397c8e32d3ee453b67&end=a9eb9c52f3e8d8b6402e6acc69b9bcfc4f371d58&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.5% | 0.5% | 1     |
+| Regressions 😿 <br /> (secondary) | 1.6% | 4.3% | 20    |
+| Improvements 🎉 <br /> (primary) | -0.3% | -0.4% | 5     |
+| Improvements 🎉 <br /> (secondary) | -0.3% | -0.3% | 3     |
+| All 😿🎉 (primary) | -0.2% | 0.5% | 6     |
+
+This is *probably* noise, but it's not very clear. Regressions are minor enough
+that further investigation does not seem warranted.
+
+Enable MIR inlining [#91743](https://github.com/rust-lang/rust/pull/91743)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=aedf78e56b2279cc869962feac5153b6ba7001ed&end=0075bb4fad68e64b6d1be06bf2db366c30bc75e1&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 1.3% | 7.2% | 54    |
+| Regressions 😿 <br /> (secondary) | 1.7% | 6.1% | 68    |
+| Improvements 🎉 <br /> (primary) | -2.6% | -10.0% | 118   |
+| Improvements 🎉 <br /> (secondary) | -3.4% | -17.3% | 76    |
+| All 😿🎉 (primary) | -1.4% | -10.0% | 172   |
+
+A fairly large improvement for some benchmarks, and particularly large for
+bootstrap times (nearly 9% win). There are some fairly large regressions to a
+few select benchmarks which stress the inlining more than helping LLVM (e.g.,
+stm32f4), but overall this is a great improvement in many cases.
+
+Avoid unnecessary work in `finalize_resolutions_in`. [#98569](https://github.com/rust-lang/rust/pull/98569)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=f2d93935ffba3ab9d7ccb5300771a2d29b4c8bf3&end=5f98537eb7b5f42c246a52c550813c3cff336069&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | 0.3% | 0.5% | 7     |
+| Regressions 😿 <br /> (secondary) | 0.5% | 0.7% | 7     |
+| Improvements 🎉 <br /> (primary) | -1.0% | -1.0% | 2     |
+| Improvements 🎉 <br /> (secondary) | -2.1% | -2.4% | 6     |
+| All 😿🎉 (primary) | 0.0% | -1.0% | 9     |
+
+Wins/losses balance out; already labeled as triaged.
+
+Don't use match-destructuring for derived ops on structs. [#98446](https://github.com/rust-lang/rust/pull/98446)
+[(Comparison Link)](https://perf.rust-lang.org/compare.html?start=2557603f320593be9d1c29a453c648e61e74d343&end=d46c728bcda687b1cf5f3bedca3d501e797b2a0f&stat=instructions:u)
+
+|            | mean | max | count |
+|:----------:|:----:|:---:|:-----:|
+| Regressions 😿 <br /> (primary) | N/A  | N/A | 0     |
+| Regressions 😿 <br /> (secondary) | 1.3% | 1.9% | 19    |
+| Improvements 🎉 <br /> (primary) | -0.6% | -1.5% | 66    |
+| Improvements 🎉 <br /> (secondary) | -5.4% | -12.3% | 33    |
+| All 😿🎉 (primary) | -0.6% | -1.5% | 66    |
+
+Overall an excellent, though somewhat small, improvement. Regressions are small
+and limited to a couple very artificial stress tests rather than real-world
+benchmarks.