What if we always run ReorderBasicBlocks?
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@bors try @rust-timer queue |
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What if we always run `ReorderBasicBlocks`? Obviously we don't *need* to run this, but I keep being sad when I look at MIR on the playground that it's really awkward to read because you have to jump around all over because whenever something's inlined it's put at the end. So what if we just do it when we're optimizing anyway? Can we afford it?
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☀️ Try build successful - checks-actions |
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Finished benchmarking commit (c180af9): comparison URL. Overall result: ❌ regressions - please read the text belowBenchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf. Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @bors rollup=never Instruction countThis is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.
Max RSS (memory usage)Results (primary -1.7%, secondary 2.4%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
CyclesResults (secondary 2.3%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
Binary sizeResults (primary -0.0%, secondary 0.3%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
Bootstrap: 776.099s -> 775.714s (-0.05%) |
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| fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { | ||
| let rpo: IndexVec<BasicBlock, BasicBlock> = | ||
| body.basic_blocks.reverse_postorder().iter().copied().collect(); | ||
| let rpo = IndexSlice::from_raw(body.basic_blocks.reverse_postorder()); | ||
| if rpo.iter().is_sorted() { |
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the "is_sorted" method also exists on slices which might be faster
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@bors try @rust-timer queue |
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What if we always run `ReorderBasicBlocks`? Obviously we don't *need* to run this, but I keep being sad when I look at MIR on the playground that it's really awkward to read because you have to jump around all over because whenever something's inlined it's put at the end. So what if we just do it when we're optimizing anyway? Can we afford it?
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☀️ Try build successful - checks-actions |
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Finished benchmarking commit (f4b899e): comparison URL. Overall result: ❌ regressions - please read the text belowBenchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf. Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @bors rollup=never Instruction countThis is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.
Max RSS (memory usage)Results (secondary -2.6%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
CyclesResults (primary 0.7%, secondary 2.2%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
Binary sizeResults (primary -0.0%, secondary 0.3%)This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
Bootstrap: 773.955s -> 774.03s (0.01%) |
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Yeah, I can't really fight for that perf hit when it's just to make stuff pretty. |
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Obviously we don't need to run this, but I keep being sad when I look at MIR on the playground that it's really awkward to read because you have to jump around all over because whenever something's inlined it's put at the end.
So what if we just do it when we're optimizing anyway? Can we afford it?