[PATCH] D18867: [IndVarSimplify] Eliminate zext of a signed IV when the IV is known to be non-negative

[Sanjoy Das via llvm-commits]

sanjoy added a comment.

Hi @lihuang,

Using `isKnownNonNegative` is fine, but please add a comment stating
why you're doing that (to work around conservatism in
`ScalarEvolution` around no-wrap flags).


https://reviews.llvm.org/D18867