[llvm] Add known and demanded bits support for zext nneg (PR #70858)

[Philip Reames via llvm-commits]

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@@ -414,7 +414,10 @@ Value *InstCombinerImpl::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
     if (SimplifyDemandedBits(I, 0, InputDemandedMask, InputKnown, Depth + 1))
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preames wrote:

Pulled the bugfix into it's own review, see https://github.com/llvm/llvm-project/pull/71088

https://github.com/llvm/llvm-project/pull/70858