[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges.

Summary: This patch introduces two new iterator ranges and updates existing code to use it.  No functional change intended.

Test Plan: All tests (make check-all) still pass.

Reviewers: dblaikie

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4481

llvm-svn: 213474
diff --git a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
index 80bd516..dc12f97 100644
--- a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -233,9 +233,7 @@
       if (PN->getIncomingBlock(i) != NewBB)
         OtherPreds.push_back(PN->getIncomingBlock(i));
   } else {
-    for (pred_iterator I = pred_begin(DestBB), E = pred_end(DestBB);
-         I != E; ++I) {
-      BasicBlock *P = *I;
+    for (BasicBlock *P : predecessors(DestBB)) {
       if (P != NewBB)
         OtherPreds.push_back(P);
     }
@@ -321,9 +319,7 @@
         // the predecessor must be directly in TIL, not in a subloop, or again
         // LoopSimplify doesn't hold.
         SmallVector<BasicBlock *, 4> LoopPreds;
-        for (pred_iterator I = pred_begin(DestBB), E = pred_end(DestBB); I != E;
-             ++I) {
-          BasicBlock *P = *I;
+        for (BasicBlock *P : predecessors(DestBB)) {
           if (P == NewBB)
             continue; // The new block is known.
           if (LI->getLoopFor(P) != TIL) {