[InstCombine] Support folding of add instructions with vector constants into select operations

We currently only fold scalar add of constants into selects. This improves this to support vectors too.

Differential Revision: https://reviews.llvm.org/D31683



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299847 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed