Summary:
An unsigned comparision is equivalent to is corresponding signed version
if both the operands being compared are positive. Teach SCEV to use
this fact when profitable.
Reviewers: atrick, hfinkel, reames, nlewycky
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13687
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251051 91177308-0d34-0410-b5e6-96231b3b80d8