diff --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -410,6 +410,19 @@
 
   virtual ~VPBlockBase() = default;
 
+  using pred_iterator = SmallVectorImpl<VPBlockBase *>::iterator;
+  using const_pred_iterator = SmallVectorImpl<VPBlockBase *>::const_iterator;
+  using succ_iterator = SmallVectorImpl<VPBlockBase *>::iterator;
+  using const_succ_iterator = SmallVectorImpl<VPBlockBase *>::const_iterator;
+  pred_iterator pred_begin() { return Predecessors.begin(); }
+  const_pred_iterator pred_begin() const { return Predecessors.begin(); }
+  pred_iterator pred_end() { return Predecessors.end(); }
+  const_pred_iterator pred_end() const { return Predecessors.end(); }
+  succ_iterator succ_begin() { return Successors.begin(); }
+  const_succ_iterator succ_begin() const { return Successors.begin(); }
+  succ_iterator succ_end() { return Successors.end(); }
+  const_succ_iterator succ_end() const { return Successors.end(); }
+
   const std::string &getName() const { return Name; }
 
   void setName(const Twine &newName) { Name = newName.str(); }