Switch more loops to be range-based

This makes the code a little more concise, no functional change is
intended.

llvm-svn: 273644
diff --git a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
index 802b3e4..ff46d81 100644
--- a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
@@ -501,21 +501,21 @@
   // Reset the visited nodes
   Visited.clear();
 
-  for (RNVector::reverse_iterator OI = Order.rbegin(), OE = Order.rend();
-       OI != OE; ++OI) {
+  for (RegionNode *RN : reverse(Order)) {
 
-    DEBUG(dbgs() << "Visiting: " <<
-                    ((*OI)->isSubRegion() ? "SubRegion with entry: " : "") <<
-                    (*OI)->getEntry()->getName() << " Loop Depth: " << LI->getLoopDepth((*OI)->getEntry()) << "\n");
+    DEBUG(dbgs() << "Visiting: "
+                 << (RN->isSubRegion() ? "SubRegion with entry: " : "")
+                 << RN->getEntry()->getName() << " Loop Depth: "
+                 << LI->getLoopDepth(RN->getEntry()) << "\n");
 
     // Analyze all the conditions leading to a node
-    gatherPredicates(*OI);
+    gatherPredicates(RN);
 
     // Remember that we've seen this node
-    Visited.insert((*OI)->getEntry());
+    Visited.insert(RN->getEntry());
 
     // Find the last back edges
-    analyzeLoops(*OI);
+    analyzeLoops(RN);
   }
 }