[PATCH] D30826: [DAG] vector div/rem with any zero element in divisor is undef

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

In https://reviews.llvm.org/D30826#698045, @efriedma wrote:

> I agree it's weird that there are two functions for constant folding... but you can leave it for now, I guess.
>
> Maybe check for null or undef, rather than just null?






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Comment at: include/llvm/CodeGen/SelectionDAG.h:744
+  /// For the given opcode and operand values, return true if any operand value
+  /// makes this operation undefined.
+  bool isUndef(unsigned Opcode, ArrayRef<SDValue> Ops);
----------------
efriedma wrote:
> This is a little unclear... maybe "return true if the result of this operation is always undefined"?
Yep - that's better. Thanks!


https://reviews.llvm.org/D30826