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diff --git a/llvm/lib/Transforms/Vectorize/VPlanHCFGBuilder.h b/llvm/lib/Transforms/Vectorize/VPlanHCFGBuilder.h
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+//===-- VPlanHCFGBuilder.h --------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines the VPlanHCFGBuilder class which contains the public
+/// interface (buildHierarchicalCFG) to build a VPlan-based Hierarchical CFG
+/// (H-CFG) for an incoming IR.
+///
+/// A H-CFG in VPlan is a control-flow graph whose nodes are VPBasicBlocks
+/// and/or VPRegionBlocks (i.e., other H-CFGs). The outermost H-CFG of a VPlan
+/// consists of a VPRegionBlock, denoted Top Region, which encloses any other
+/// VPBlockBase in the H-CFG. This guarantees that any VPBlockBase in the H-CFG
+/// other than the Top Region will have a parent VPRegionBlock and allows us
+/// to easily add more nodes before/after the main vector loop (such as the
+/// reduction epilogue).
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_VECTORIZE_VPLAN_VPLANHCFGBUILDER_H
+#define LLVM_TRANSFORMS_VECTORIZE_VPLAN_VPLANHCFGBUILDER_H
+
+#include "VPlan.h"
+#include "VPlanVerifier.h"
+
+namespace llvm {
+
+class Loop;
+
+/// Main class to build the VPlan H-CFG for an incoming IR.
+class VPlanHCFGBuilder {
+private:
+  // The outermost loop of the input loop nest considered for vectorization.
+  Loop *TheLoop;
+
+  // Loop Info analysis.
+  LoopInfo *LI;
+
+  // VPlan verifier utility.
+  VPlanVerifier Verifier;
+
+public:
+  VPlanHCFGBuilder(Loop *Lp, LoopInfo *LI) : TheLoop(Lp), LI(LI) {}
+
+  /// Build H-CFG for TheLoop and update \p Plan accordingly.
+  void buildHierarchicalCFG(VPlan &Plan);
+};
+} // namespace llvm
+
+#endif // LLVM_TRANSFORMS_VECTORIZE_VPLAN_VPLANHCFGBUILDER_H