[PATCH] D59541: [InstSimplify] SimplifyICmpInst - icmp eq/ne %X, undef -> undef

[Sanjay Patel via Phabricator via llvm-commits]

spatel accepted this revision.
spatel added a comment.
This revision is now accepted and ready to land.

LGTM



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Comment at: lib/Analysis/InstructionSimplify.cpp:3053
+  // predicate pass or fail, so we can return undef.
+  // Also, if both operands are undef, we can return undef.
+  // Matches behavior in llvm::ConstantFoldCompareInstruction.
----------------
If both operands are undef, we should not get here - that should always get constant folded above this.
So I'd remove that line of the code comment. You could add an assert to be extra safe...although that general sequence (handle constant folding first) happens in all or almost all functions within InstSimplify.


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