[CallSiteSplit] Make sure we remove nonnull if the parameter turns out to be a constant.

Summary: We do not need nonull attribute if we know an argument is going to be constant.

Reviewers: junbuml, davide, fhahn

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45608

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330641 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed