[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/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 57e22e2..af7ecff 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -1052,9 +1052,8 @@
 
     if (OptLevel != CodeGenOpt::None) {
       bool AllPredsVisited = true;
-      for (const_pred_iterator PI = pred_begin(LLVMBB), PE = pred_end(LLVMBB);
-           PI != PE; ++PI) {
-        if (!FuncInfo->VisitedBBs.count(*PI)) {
+      for (const BasicBlock *Pred : predecessors(LLVMBB)) {
+        if (!FuncInfo->VisitedBBs.count(Pred)) {
           AllPredsVisited = false;
           break;
         }