[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/Analysis/BranchProbabilityInfo.cpp b/llvm/lib/Analysis/BranchProbabilityInfo.cpp
index bbd8750..a1e4d8e 100644
--- a/llvm/lib/Analysis/BranchProbabilityInfo.cpp
+++ b/llvm/lib/Analysis/BranchProbabilityInfo.cpp
@@ -530,9 +530,8 @@
   assert(LastF && "Cannot print prior to running over a function");
   for (Function::const_iterator BI = LastF->begin(), BE = LastF->end();
        BI != BE; ++BI) {
-    for (succ_const_iterator SI = succ_begin(BI), SE = succ_end(BI);
-         SI != SE; ++SI) {
-      printEdgeProbability(OS << "  ", BI, *SI);
+    for (const BasicBlock *Succ : successors(BI)) {
+      printEdgeProbability(OS << "  ", BI, Succ);
     }
   }
 }
@@ -563,8 +562,7 @@
   uint32_t MaxWeight = 0;
   BasicBlock *MaxSucc = nullptr;
 
-  for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
-    BasicBlock *Succ = *I;
+  for (BasicBlock *Succ : successors(BB)) {
     uint32_t Weight = getEdgeWeight(BB, Succ);
     uint32_t PrevSum = Sum;