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Merged
merged 1 commit into from
Aug 20, 2025
Merged

Pass alloc-variant-zeroed to LLVM #144086

merged 1 commit into from
Aug 20, 2025

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clubby789
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@clubby789 clubby789 commented Jul 17, 2025 •
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Makes use of llvm/llvm-project#138299 (once we pull in a version of LLVM with this attribute). Unfortunately also requires llvm/llvm-project#149336 to work.

Closes #104847

@rustbot rustbot added A-LLVM Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues. S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Jul 17, 2025
@clubby789 clubby789 added the S-blocked Status: Blocked on something else such as an RFC or other implementation work. label Jul 17, 2025
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bors commented Jul 22, 2025

☔ The latest upstream changes (presumably #144249) made this pull request unmergeable. Please resolve the merge conflicts.

@clubby789 clubby789 removed the S-blocked Status: Blocked on something else such as an RFC or other implementation work. label Aug 13, 2025
@clubby789 clubby789 marked this pull request as ready for review August 13, 2025 13:30
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rustbot commented Aug 13, 2025

r? @fee1-dead

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@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Aug 13, 2025
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clubby789 commented Aug 13, 2025 •
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r? compiler

edit: oops I guess that's automatic 😅

@rustbot rustbot assigned lcnr and unassigned fee1-dead Aug 13, 2025
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nikic commented Aug 13, 2025

@bors try @rust-timer queue

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rust-bors bot added a commit that referenced this pull request Aug 13, 2025
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Auto merge of #144086 - clubby789:alloc-zeroed, r=<try>
f993fda 
Pass `alloc-variant-zeroed` to LLVM
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@rustbot rustbot added the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Aug 13, 2025
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rust-bors bot commented Aug 13, 2025

💔 Test for f993fda failed: CI. Failed jobs:

@clubby789 clubby789 added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Aug 13, 2025
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nikic commented Aug 13, 2025

I think the alloc symbols are mangled nowadays, so we need to pass the symbols with the proper mangling.

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Going to try once more before I merge
@bors try jobs=x86_64-rust-for-linux,dist-x86_64-linux,dist-aarch64-linux

rust-bors bot added a commit that referenced this pull request Aug 19, 2025
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Auto merge of #144086 - clubby789:alloc-zeroed, r=<try>
dcb0df3 
Pass `alloc-variant-zeroed` to LLVM

try-job: x86_64-rust-for-linux
try-job: dist-x86_64-linux
try-job: dist-aarch64-linux
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rust-bors bot commented Aug 19, 2025

☀️ Try build successful (CI)
Build commit: dcb0df3 (dcb0df3524e0dc8c397f2dc747840e6de6d06cea, parent: 16ad385579cebb6f7d53367c552661b6b51a4a02)

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@bors retry

@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 Aug 20, 2025
bors added a commit that referenced this pull request Aug 20, 2025
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Auto merge of #144086 - clubby789:alloc-zeroed, r=nikic
3372b83 
Pass `alloc-variant-zeroed` to LLVM

Makes use of llvm/llvm-project#138299 (once we pull in a version of LLVM with this attribute). ~~Unfortunately also requires llvm/llvm-project#149336 to work.~~

Closes #104847
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bors commented Aug 20, 2025

⌛ Testing commit 3e9316a with merge 3372b83...

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bors commented Aug 20, 2025

💔 Test failed - checks-actions

@bors bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Aug 20, 2025
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nikic commented Aug 20, 2025

Looks like the call to @"_ZN62_$LT$T$u20$as$u20$alloc..vec..spec_from_elem..SpecFromElem$GT$9from_elem17h22fb7d61224751b4E" in @vec_zero_tuple doesn't get inlined on wasm-wasip1 for whatever reason. Should probably restore the only-x86_64.

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@bors retry

@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 Aug 20, 2025
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nikic commented Aug 20, 2025

@bors r+

(retry is only if you make no changes)

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bors commented Aug 20, 2025

📌 Commit 8ea3b09 has been approved by nikic

It is now in the queue for this repository.

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bors commented Aug 20, 2025

⌛ Testing commit 8ea3b09 with merge 040a98a...

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bors commented Aug 20, 2025

☀️ Test successful - checks-actions
Approved by: nikic
Pushing 040a98a to master...

@bors bors added the merged-by-bors This PR was explicitly merged by bors. label Aug 20, 2025
@bors bors merged commit 040a98a into rust-lang:master Aug 20, 2025
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@rustbot rustbot added this to the 1.91.0 milestone Aug 20, 2025
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What is this? This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing e8a792d (parent) -> 040a98a (this PR)

Test differences

Show 18 test diffs

Stage 1

  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> ignore (ignored when the LLVM version 20.1.2 is older than 21.0.0) (J1)
  • [codegen] tests/codegen-llvm/vec-calloc.rs: pass -> [missing] (J4)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#normal: [missing] -> pass (J4)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> ignore (ignored when the LLVM version 19.1.1 is older than 21.0.0) (J7)

Stage 2

  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> ignore (ignored when the LLVM version 20.1.2 is older than 21.0.0) (J0)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> ignore (ignored when the LLVM version 19.1.1 is older than 21.0.0) (J2)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> pass (J3)
  • [codegen] tests/codegen-llvm/vec-calloc.rs: ignore (only executed when the architecture is x86_64) -> [missing] (J5)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#llvm21: [missing] -> ignore (only executed when the architecture is x86_64) (J5)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#normal: [missing] -> ignore (only executed when the architecture is x86_64) (J5)
  • [codegen] tests/codegen-llvm/vec-calloc.rs: pass -> [missing] (J6)
  • [codegen] tests/codegen-llvm/vec-calloc.rs#normal: [missing] -> pass (J6)

Additionally, 6 doctest diffs were found. These are ignored, as they are noisy.

Job group index

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard 040a98af70f0a7da03f3d5356531b28a2a7a77e4 --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

  1. dist-aarch64-linux: 6499.1s -> 8945.1s (37.6%)
  2. i686-msvc-2: 7878.1s -> 9200.7s (16.8%)
  3. x86_64-gnu-llvm-19: 2500.1s -> 2889.0s (15.6%)
  4. dist-aarch64-msvc: 6223.6s -> 5256.9s (-15.5%)
  5. pr-check-1: 1396.0s -> 1583.7s (13.4%)
  6. i686-gnu-2: 5456.9s -> 6097.5s (11.7%)
  7. dist-apple-various: 4804.6s -> 4248.7s (-11.6%)
  8. x86_64-gnu-tools: 3409.6s -> 3803.3s (11.5%)
  9. aarch64-gnu-llvm-19-2: 2177.7s -> 2413.3s (10.8%)
  10. aarch64-gnu: 6585.3s -> 7219.1s (9.6%)
How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

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Finished benchmarking commit (040a98a): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

mean range count
Regressions ❌
(primary)		 - - 0
Regressions ❌
(secondary)		 - - 0
Improvements ✅
(primary)		 - - 0
Improvements ✅
(secondary)		 -0.3% [-0.4%, -0.2%] 7
All ❌✅ (primary) - - 0

Max RSS (memory usage)

Results (secondary 2.4%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

mean range count
Regressions ❌
(primary)		 - - 0
Regressions ❌
(secondary)		 2.4% [2.4%, 2.4%] 1
Improvements ✅
(primary)		 - - 0
Improvements ✅
(secondary)		 - - 0
All ❌✅ (primary) - - 0

Cycles

Results (secondary -0.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

mean range count
Regressions ❌
(primary)		 - - 0
Regressions ❌
(secondary)		 3.6% [3.2%, 4.0%] 2
Improvements ✅
(primary)		 - - 0
Improvements ✅
(secondary)		 -3.7% [-4.4%, -3.1%] 3
All ❌✅ (primary) - - 0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 471.66s -> 471.047s (-0.13%)
Artifact size: 378.20 MiB -> 378.31 MiB (0.03%)

@rustbot rustbot removed the perf-regression Performance regression. label Aug 20, 2025
github-actions bot pushed a commit to model-checking/verify-rust-std that referenced this pull request Aug 26, 2025
@bors
Auto merge of rust-lang#144086 - clubby789:alloc-zeroed, r=nikic
9bcee26 
Pass `alloc-variant-zeroed` to LLVM

Makes use of llvm/llvm-project#138299 (once we pull in a version of LLVM with this attribute). ~~Unfortunately also requires llvm/llvm-project#149336 to work.~~

Closes rust-lang#104847
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Successfully merging this pull request may close these issues.

[ER] Sub-optimal allocation of simple zeroed Vec of arrays
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