[PATCH] D75576: [SDAG] simplify FP binops to undef

[Juneyoung Lee via Phabricator via llvm-commits]

aqjune added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7307
+  // If this operation has 'nnan' or 'ninf' and at least 1 poison operand (an
+  // undef operand can be chosen to be a poisonous value), then the result of
+  // this operation is undef.
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Nit: I think it is opposite; poison -> undef is allowed, but undef -> poison is not allowed. LangRef says a poison value may be relaxed into an undef value, which takes an arbitrary bit-pattern.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75576/new/

https://reviews.llvm.org/D75576