Summary:
PR24757 was caused by some incorect math in
`ScalarEvolution::HowFarToZero` -- the smallest unsigned solution for X
in
2^N * A = 2^N * X
is not necessarily A.
Reviewers: atrick, majnemer, meheff
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D12721
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247242 91177308-0d34-0410-b5e6-96231b3b80d8
