[RuntimeUnrolling] NFC: Add TODO and comments in connectProlog

Currently, runtime unrolling does not support loops where multiple
exiting blocks exit to the latchExit. Added TODO and other code
clarifications for ConnectProlog code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349944 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed