[PATCH] D89976: [ValueTracking] add range limits for ctpop

[Sanjay Patel via Phabricator via llvm-commits]

spatel created this revision.
spatel added reviewers: davezarzycki, lebedev.ri, RKSimon.
Herald added subscribers: hiraditya, mcrosier.
Herald added a project: LLVM.
spatel requested review of this revision.

As discussed in D89952 <https://reviews.llvm.org/D89952>, instcombine can sometimes find a way to reduce similar patterns, but it is incomplete.
InstSimplify uses the computeConstantRange() ValueTracking analysis via simplifyICmpWithConstant(), so we just need to fill in the max value of ctpop to process any "icmp pred ctpop(X), C" pattern (the min value is initialized to zero automatically).


https://reviews.llvm.org/D89976

Files:
  llvm/lib/Analysis/ValueTracking.cpp
  llvm/test/Transforms/InstSimplify/compare.ll

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