Update to LLVM 22 #150722
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Update to LLVM 22 #150722
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These commits modify compiler targets. |
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@bors try @rust-timer queue |
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Finished benchmarking commit (dabe9cd): comparison URL. Overall result: ❌✅ regressions and improvements - please read the text belowBenchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf. Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @bors rollup=never Instruction countOur most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.
Max RSS (memory usage)Results (primary 1.0%, secondary -1.3%)A less reliable metric. May be of interest, but not used to determine the overall result above.
CyclesResults (primary 3.2%, secondary 2.1%)A less reliable metric. May be of interest, but not used to determine the overall result above.
Binary sizeResults (primary -0.6%, secondary -1.1%)A less reliable metric. May be of interest, but not used to determine the overall result above.
Bootstrap: 473.133s -> 480.877s (1.64%) |
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☔ The latest upstream changes made this pull request unmergeable. Please resolve the merge conflicts. |
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☔ The latest upstream changes (presumably #150726) made this pull request unmergeable. Please resolve the merge conflicts. |
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Based on helloworld, the perf regressions seem to be related to the allocator somehow. Previously tcache_alloc_small_hard was called 3 times, now it's called 189 times. The total number of allocations is smaller, but the time spent in the allocator is larger. |
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Or maybe the issue is not actually the allocator behavior itself. I suspect that we might have lost LTO on jemalloc and tcache_alloc_small_hard previously got inlined into malloc_default but now no longer is. Possibly updating the host toolchain at the same time so that the versions match will help. |
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Finished benchmarking commit (b02fa67): comparison URL. Overall result: ❌✅ regressions and improvements - BENCHMARK(S) FAILEDBenchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf. Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @bors rollup=never ❗ ❗ ❗ ❗ ❗
❗ ❗ ❗ ❗ ❗ Instruction countOur most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.
Max RSS (memory usage)Results (primary 2.5%, secondary 0.5%)A less reliable metric. May be of interest, but not used to determine the overall result above.
CyclesResults (primary 4.1%, secondary 0.0%)A less reliable metric. May be of interest, but not used to determine the overall result above.
Binary sizeResults (primary -0.5%, secondary -1.1%)A less reliable metric. May be of interest, but not used to determine the overall result above.
Bootstrap: missing data |
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The rustc bootstrap failure is because the try build hasn't produced the |
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Given that the perf run from two days ago worked, maybe something related to the bors switchover affected this? At least the across the board regressions are gone now. Looks like we need to update the host toolchain in sync going forward to avoid this issue. |
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Yeah, that's most likely. But the weird thing is that I actually consider the new behavior to be correct 😆 Anyway, I'll investigate. |
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Btw, looks like your LLVM changes @Mark-Simulacrum made BOLT optimizations faster 🎉! 5m => 3m for LLVM, and 10m => 5m for rustc. |
This changed in: llvm/llvm-project@853760b
Since LLVM 22 the alloca must be passed directly. Do this by stripping the addrspacecast if it exists.
As Intel has walked back on the existence of AVX 10.1-256, LLVM no longer uses evex512 and avx-10.n-512 are now avx-10.n instead, so we can skip all the special handling on LLVM 22.
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This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed. Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers. |
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@bors try jobs=dist-aarch64-linux,aarch64-gnu,aarch64-gnu-debug,dist-x86_64-apple,dist-apple-various,dist-aarch64-apple,aarch64-apple |
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Update to LLVM 22 try-job: dist-aarch64-linux try-job: aarch64-gnu try-job: aarch64-gnu-debug try-job: dist-x86_64-apple try-job: dist-apple-various try-job: dist-aarch64-apple try-job: aarch64-apple
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The job Click to see the possible cause of the failure (guessed by this bot) |
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💔 Test for 83eb5cb failed: CI. Failed jobs:
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https://github.com/llvm/llvm-project/blob/c620b477512ad566e687024d25b703ba0f99cec2/llvm/lib/Object/OffloadBundle.cpp#L191 asserts on MacOS for |
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@bors try jobs=x86_64-mingw-1,x86_64-mingw-2,dist-i686-mingw,dist-x86_64-mingw,dist-aarch64-llvm-mingw,dist-x86_64-llvm-mingw |
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⌛ Trying commit 3390d2a with merge 1d9f387… To cancel the try build, run the command Workflow: https://github.com/rust-lang/rust/actions/runs/20989561580 |
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Update to LLVM 22 try-job: x86_64-mingw-1 try-job: x86_64-mingw-2 try-job: dist-i686-mingw try-job: dist-x86_64-mingw try-job: dist-aarch64-llvm-mingw try-job: dist-x86_64-llvm-mingw
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Scheduled release date: Feb 24
1.94 becomes stable: Mar 5
Depends on: