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Differential D62144

[LoopUnroll] Add FlagNUW for backedge count
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Authored by samparker on May 20 2019, 8:13 AM.

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Reviewers
anna
dmgreen
mkazantsev
Summary

While performing runtime unrolling, we assign the backedge taken count as TripCount - 1. So, if we can prove that TripCount > 0, then we know that the backedge count is nuw.

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Event Timeline

samparker created this revision.May 20 2019, 8:13 AM
Herald added subscribers: sanjoy, zzheng. · View Herald TranscriptMay 20 2019, 8:13 AM
samparker added a parent revision: D61934: [SCEV] Use wrap flags in InsertBinop.May 20 2019, 8:13 AM
samparker abandoned this revision.Jun 9 2019, 11:15 PM

This is broken, as well as the patch is depends on!

Revision Contents
Changeset List

PathSize
lib/
Transforms/
Utils/
19 lines
test/
Transforms/
IndVarSimplify/
2 lines
LoopUnroll/
30 lines
4 lines
LoopUnrollAndJam/
2 lines

Diff 200288

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lib/Transforms/Utils/LoopUnrollRuntime.cpp

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test/Transforms/IndVarSimplify/lftr.ll

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test/Transforms/LoopUnroll/nuw-backedge.ll

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test/Transforms/LoopUnroll/runtime-unroll-remainder.ll

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test/Transforms/LoopUnrollAndJam/unroll-and-jam.ll

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