[llvm] [InstCombine] Fold shift of boolean zext to logic sequence (PR #180596)

[Nikita Popov via llvm-commits]

nikic wrote:

It looks like we even already have such a fold for icmp of add of sext/zext: https://github.com/llvm/llvm-project/blob/f81889da29eec1a70283986fc0a654b9d628157a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp#L3137-L3161 Generalizing the foldICmpBinOpWithConstantViaTruthTable() fold would both subsume that and cover this case. And cover mix of ext + select.

https://github.com/llvm/llvm-project/pull/180596