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[LoopUnroll] allow customization of threshold for new-pm
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Authored by wenju on Apr 24 2022, 7:58 PM.

Details

Reviewers

chandlerc
tejohnson
dmgreen
fhahn

Summary

Legacy createLoopUnrollPass provides threshold parameter. This patch
brings the support to new-pm LoopUnrollPass.

Our downstream uses LoopUnroll pass with small threshold for fine tuning, so we want the support for new pm.

Diff Detail

Unit TestsFailed
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	Time	Test
	410 ms	x64 debian > HWAddressSanitizer-x86_64.TestCases::hwasan_symbolize.cpp
	60,160 ms	x64 debian > LLVM.CodeGen/NVPTX::wmma.py
	60,020 ms	x64 debian > libFuzzer.libFuzzer::large.test

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wenju created this revision.Apr 24 2022, 7:58 PM

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wenju requested review of this revision.Apr 24 2022, 7:58 PM

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Harbormaster completed remote builds in B161094: Diff 424811.Apr 24 2022, 8:40 PM

Do you have any plans to add a user of the new Threshold option upstream

In D124355#3471091, @fhahn wrote:

Do you have any plans to add a user of the new Threshold option upstream

I don't have this plan. createLoopUnrollPass in standard pipeline uses default threshold parameter.

Can you just have getUnrollingPreferences override the UP.Threshold for your target? Or is it that you want a specific run of the unroll pass to have a lower threshold than other runs?

In D124355#3471198, @dmgreen wrote:

Can you just have getUnrollingPreferences override the UP.Threshold for your target?

Thanks for the suggestion.

Or is it that you want a specific run of the unroll pass to have a lower threshold than other runs?

Yes, our pipeline contains several calls of LoopUnroll pass with different thresholds, so I think getUnrollingPreferences or overriding command line option wouldn't work.