llvm-cov: Don't pointlessly create a unique_ptr (NFC)

There's no ownership going on here, and no reason to heap allocate
this object.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217113 91177308-0d34-0410-b5e6-96231b3b80d8
IndVarSimplify: Address review comments for r217102

No functional change intended, just some cleanups and comments added.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217115 91177308-0d34-0410-b5e6-96231b3b80d8