The more precise known bits analysis for GEPs introduced in D86364 assumes that inbounds implies nsw for the additions. This is not the case, as the base pointer is an unsigned value.

I was not able to come up with a test case where this actually makes a difference, because KnownBits::computeMul() is too imprecise (doing something like adding a non-negative base and a non-negative offset fails because multiplication by 1 loses the non-negativity information.)