Make LoopInfoBase more generic, in preparation for having MachineLoopInfo.  This involves a small interface change.

llvm-svn: 44348
diff --git a/llvm/lib/Transforms/Scalar/LoopUnroll.cpp b/llvm/lib/Transforms/Scalar/LoopUnroll.cpp
index d518e3a..f1a6df4 100644
--- a/llvm/lib/Transforms/Scalar/LoopUnroll.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopUnroll.cpp
@@ -358,7 +358,7 @@
            VI != VE; ++VI)
         LastValueMap[VI->first] = VI->second;
 
-      L->addBasicBlockToLoop(New, *LI);
+      L->addBasicBlockToLoop(New, LI->getBase());
 
       // Add phi entries for newly created values to all exit blocks except
       // the successor of the latch block.  The successor of the exit block will