Skip to content

Update triage-2020-12-15 #812

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Dec 15, 2020
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions triage/2020-12-15.md
Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,7 @@ Accept arbitrary expressions in key-value attributes at parse time[#78837](https
Capture precise paths in THIR and MIR[#79553](https://github.com/rust-lang/rust/issues/79553)
- Moderate regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=9eb3a7ceafd1e2c1924177caa18c7cc0c25b413e&end=5bd9b60333b3dc0a51e7a5607cd1e0d537a9f718&stat=instructions:u) (up to 4.5% on `incr-unchanged` builds of `clap-rs-check`)
- While this change powers a feature behind a feature flag (`capture_disjoint_fields`), it looks like it's still causing perf regressions in workloads not using this feature.
- [Pinged in the PR about this issue](https://github.com/rust-lang/rust/pull/79553#issuecomment-745435558)
- This is a known issue with [a plan](https://github.com/rust-lang/rust/pull/79553#issuecomment-745437806) for how to recover the performance loss.

Create `rustc_type_ir`[#79169](https://github.com/rust-lang/rust/issues/79169)
- Moderate regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=c3ed6681ff8d446e68ce272be4bf66f4145f6e29&end=3f2088aa603d2cd3f43c20795872de9cd6ec7735&stat=instructions:u) (up to 3.1% on `full` builds of `ctfe-stress-4-check`)
Expand All @@ -37,6 +37,7 @@ Create `rustc_type_ir`[#79169](https://github.com/rust-lang/rust/issues/79169)
Update stdarch submodule[#79938](https://github.com/rust-lang/rust/issues/79938)
- Moderate regression in [instruction counts](https://perf.rust-lang.org/compare.html?start=fa416394275d2468d104b8f72ac31b1ddf7ee52e&end=8b3ee82eb68cb35030bb745c23f8aa76d9de5bee&stat=instructions:u) (up to 1.4% on `incr-unchanged` builds of `deeply-nested-debug`)
- This was a wholesale update of the stdarch submodule.
- stdarch is using const arguments that would benefit from const generics. This might explain why compilation suffers.
* [Pinged in the PR about this issue](https://github.com/rust-lang/rust/pull/79938#issuecomment-745393740)

#### Improvements
Expand All @@ -61,5 +62,4 @@ Lower `discriminant_value` intrinsic[#79922](https://github.com/rust-lang/rust/i
#### Nags requiring follow up

- Several regressions need followup investigations. See their respective entries above for the issue.
- As mentioned last week, stdarch expansion causing a 40% libcore compile time regression is still not
resolved, and resolution is unclear.
- As mentioned last week, stdarch expansion causing a 40% libcore compile time regression is still not resolved, and resolution is unclear. This is likely a related issue to the stdarch regression listed above.