[PATCH] D115755: [InstSimplify] Fold logic And to Zero

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


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Comment at: llvm/test/Transforms/InstSimplify/and.ll:168
   %or = or i71 %x, %y
   %xor1 = xor i71 %x, %or
   %xor2 = xor i71 %y, %or
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spatel wrote:
> rampitec wrote:
> > 'or' is more complex than the argument, the xor will be commuted.
> > See InstCombiner::getComplexity() for the details. Search for "thwart complexity-based canonicalization" in the llvm/test/Transforms/InstCombine directory for test coverage that works around it.
> This is instsimplify, so we don't have to worry about the pass itself altering the input (this is shown in the baseline CHECK lines).
Ok, thanks.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D115755/new/

https://reviews.llvm.org/D115755