[PATCH] D47116: [DAGCombiner] Use computeKnownBits to match rotate patterns that have had their amount masking modified by simplifyDemandedBits.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon accepted this revision.
RKSimon added a comment.
This revision is now accepted and ready to land.

LGTM - I don't think the cost of computeKnownBits will be a perf drain, but we can revisit if necessary



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Comment at: test/CodeGen/X86/combine-rotates.ll:68
 ; CHECK-NEXT:    movl %edi, %eax
 ; CHECK-NEXT:    retq
 ; XOP-LABEL: rotate_demanded_bits:
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Can you fix this please? Old CHECKS that didn't get stripped.


https://reviews.llvm.org/D47116