[ScopInfo] Remove dependency of Scop::getLastStmtFor(BB) on getStmtFor(BB). NFC.
We are working towards removing uses of Scop::getStmtFor(BB). In this
patch, we remove dependency of Scop::getLastStmtFor(BB) on
getStmtFor(BB). To do so, we get the list of all statements
corresponding to the BB and then fetch the last one.
Contributed-by: Nandini Singhal <cs15mtech01004@iith.ac.in>
Differential Revision: https://reviews.llvm.org/D35665
git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@308633 91177308-0d34-0410-b5e6-96231b3b80d8