Add the missing 'LoopToScev' parameter

Contributed-by: Yabin Hu <yabin.hwu@gmail.com>

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@208180 91177308-0d34-0410-b5e6-96231b3b80d8
Remove unnecessary explicit typing in std::make_pair

Contributed-by: Yabin Hu <yabin.hwu@gmail.com>

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@208181 91177308-0d34-0410-b5e6-96231b3b80d8
Replace llvm::IRBuilder with PollyIRBuilder

Contributed-by:  Yabin Hu <yabin.hwu@gmail.com>

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@208182 91177308-0d34-0410-b5e6-96231b3b80d8