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

[Sanjay Patel via Phabricator via llvm-commits]

spatel 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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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).


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D115755/new/

https://reviews.llvm.org/D115755