[PATCH] D25847: [ValueTracking] Don't assume we can speculate shifts

[Davide Italiano via llvm-commits]

davide added a comment.

In https://reviews.llvm.org/D25847#575957, @efriedma wrote:

> "A shift is undefined if the second operand is equal or larger than the number of bits in the first operand."
>
> Yes... but that's not undefined behavior.  LangRef just says "the result is undefined".


hmm, does this change the fact that we don't want to speculate in this case or you're commenting on the wording?


https://reviews.llvm.org/D25847