[PATCH] D77868: [InstSimplify] fold select of bools using bitwise logic

[Sanjay Patel via Phabricator via llvm-commits]

spatel created this revision.
spatel added reviewers: lebedev.ri, nikic, aqjune, nlopes, regehr.
Herald added subscribers: hiraditya, mcrosier.

select Cond, T, false --> Cond & T
select Cond, true, F --> Cond | F

This fixes regressions that would be visible if we remove known poison-unsafe transforms in instcombine mentioned here:
https://reviews.llvm.org/D72396#1810460

I'm not sure yet how to deal with the 'and-not' and 'or-not' variations.

Alive2 example for 1 of the tests:
http://volta.cs.utah.edu:8080/z/Ue2UE3


https://reviews.llvm.org/D77868

Files:
  llvm/lib/Analysis/InstructionSimplify.cpp
  llvm/test/Transforms/InstSimplify/select.ll

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