Skip to content
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

Backport LLVM changes to disable deferred inlining #92110

Merged
merged 1 commit into from
Dec 23, 2021

Conversation

nagisa
Copy link
Member

@nagisa nagisa commented Dec 19, 2021

Fixes #91128

I was thinking of how to best add the test case from the issue, and I think rust perf infrastructure would probably be the best place for something like it.

@rust-highfive
Copy link
Collaborator

r? @cuviper

(rust-highfive has picked a reviewer for you, use r? to override)

@rust-highfive
Copy link
Collaborator

⚠️ Warning ⚠️

  • These commits modify submodules.

@rust-highfive rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Dec 19, 2021
@nagisa
Copy link
Member Author

nagisa commented Dec 19, 2021

We want to backport either this or #91190 to beta.

@nagisa nagisa added beta-nominated Nominated for backporting to the compiler in the beta channel. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Dec 19, 2021
@nagisa
Copy link
Member Author

nagisa commented Dec 23, 2021

cc @nikic

@pnkfelix
Copy link
Member

Declining to beta-backport in favor of PR #91190.

@pnkfelix
Copy link
Member

@rustbot label: -beta-nominated

@rustbot rustbot removed the beta-nominated Nominated for backporting to the compiler in the beta channel. label Dec 23, 2021
@nikic
Copy link
Contributor

nikic commented Dec 23, 2021

@bors r+ rollup=never

@bors
Copy link
Contributor

bors commented Dec 23, 2021

📌 Commit 2b821f2 has been approved by nikic

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Dec 23, 2021
@bors
Copy link
Contributor

bors commented Dec 23, 2021

⌛ Testing commit 2b821f2 with merge 77497c7...

@Aaron1011
Copy link
Member

Note that this is an LLVM backport, not a beta backport (the PR wording confused me at first)

@bors
Copy link
Contributor

bors commented Dec 23, 2021

☀️ Test successful - checks-actions
Approved by: nikic
Pushing 77497c7 to master...

@bors bors added the merged-by-bors This PR was explicitly merged by bors. label Dec 23, 2021
@bors bors merged commit 77497c7 into rust-lang:master Dec 23, 2021
@rustbot rustbot added this to the 1.59.0 milestone Dec 23, 2021
@rust-timer
Copy link
Collaborator

Finished benchmarking commit (77497c7): comparison url.

Summary: This change led to large relevant mixed results 🤷 in compiler performance.

  • Moderate improvement in instruction counts (up to -8.3% on incr-patched: println builds of regression-31157)
  • Large regression in instruction counts (up to 2.8% on full builds of deeply-nested)

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression

@rustbot rustbot added the perf-regression Performance regression. label Dec 23, 2021
bors added a commit to rust-lang-ci/rust that referenced this pull request Jan 1, 2022
Mark drop calls in landing pads `cold` instead of `noinline`

Now that deferred inlining has been disabled in LLVM (rust-lang#92110), this shouldn't cause catastrophic size blowup.

I confirmed that the test cases from rust-lang#41696 (comment) still compile quickly (<1s) after this change. ~Although note that I wasn't able to reproduce the original issue using a recent rustc/llvm with deferred inlining enabled, so those tests may no longer be representative. I was also unable to create a modified test case that reproduced the original issue.~ (edit: I reproduced it on CI by accident--the first commit timed out on the LLVM 12 builder, because I forgot to make it conditional on LLVM version)

r? `@nagisa`
cc `@arielb1` (this effectively reverts rust-lang#42771 "mark calls in the unwind path as !noinline")
cc `@RalfJung` (fixes rust-lang#46515)

edit: also fixes rust-lang#87055
bjorn3 pushed a commit to bjorn3/rust that referenced this pull request Feb 1, 2022
Mark drop calls in landing pads `cold` instead of `noinline`

Now that deferred inlining has been disabled in LLVM (rust-lang#92110), this shouldn't cause catastrophic size blowup.

I confirmed that the test cases from rust-lang#41696 (comment) still compile quickly (<1s) after this change. ~Although note that I wasn't able to reproduce the original issue using a recent rustc/llvm with deferred inlining enabled, so those tests may no longer be representative. I was also unable to create a modified test case that reproduced the original issue.~ (edit: I reproduced it on CI by accident--the first commit timed out on the LLVM 12 builder, because I forgot to make it conditional on LLVM version)

r? `@nagisa`
cc `@arielb1` (this effectively reverts rust-lang#42771 "mark calls in the unwind path as !noinline")
cc `@RalfJung` (fixes rust-lang#46515)

edit: also fixes rust-lang#87055
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
merged-by-bors This PR was explicitly merged by bors. perf-regression Performance regression. S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
Projects
None yet
Development

Successfully merging this pull request may close these issues.

Huge compile-time regression in beta/nightly
9 participants