[PATCH] D28853: [SelectionDAG] Improve knownbits handling of UMIN/UMAX (PR31293)

[Matt Arsenault via Phabricator via llvm-commits]

arsenm accepted this revision.
arsenm added inline comments.
This revision is now accepted and ready to land.


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Comment at: lib/CodeGen/SelectionDAG/SelectionDAG.cpp:2712-2715
+    // UMAX - we know that the result will have the maximum of the
+    // known one leading bits of the inputs.
+    unsigned LeadOne = KnownOne.countLeadingOnes();
+    LeadOne = std::max(LeadOne, KnownOne2.countLeadingOnes());
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Should it also be the minimum of the known leading 0s?


Repository:
  rL LLVM

https://reviews.llvm.org/D28853