IRGen: Switch LLVM pipeline optimization level from Os to O2#89632
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AnthonyLatsis wants to merge 2 commits into
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IRGen: Switch LLVM pipeline optimization level from Os to O2#89632AnthonyLatsis wants to merge 2 commits into
AnthonyLatsis wants to merge 2 commits into
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@swift-ci please benchmark |
kavon
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LGTM assuming no significant changes in the benchmark results
hamishknight
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| // Splitting trades code size to enhance memory locality, avoid in -Osize. | ||
| DoHotColdSplit = Opts.EnableHotColdSplit && !Opts.optimizeForSize(); | ||
| level = llvm::OptimizationLevel::Os; | ||
| level = llvm::OptimizationLevel::O2; |
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Can you add a comment here covering what you have in the PR description? Just so it's obvious for future folks reading the code
AnthonyLatsis
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@swift-ci please benchmark |
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We got improvements and regressions. Now trying Os → O2 plus adding the |
Os is gone upstream: llvm/llvm-project#191363. This can only affect `-O` builds: * We always emit IR functions with the `optsize` and `minsize` attributes in `-Osize` mode. * The only place in LLVM where pipeline Os matters is `FunctionSpecializer`, where we already skip functions with the `optsize` or `minsize` attribute.
This reverts commit 2cb0f2c.
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Os is gone upstream: llvm/llvm-project#191363. This change can only affect
-Obuilds:optsizeandminsizeattributes in-Osizemode:swift/lib/IRGen/IRGenModule.cpp
Lines 1560 to 1565 in 85e5036
FunctionSpecializer, where we already skip functions with theoptsizeorminsizeattribute.