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diff --git a/include/llvm/Transforms/Scalar/LoopSink.h b/include/llvm/Transforms/Scalar/LoopSink.h
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+++ b/include/llvm/Transforms/Scalar/LoopSink.h
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+//===- LoopSink.h - Loop Sink Pass ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the interface for the Loop Sink pass.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
+#define LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
+
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/Transforms/Scalar/LoopPassManager.h"
+
+namespace llvm {
+
+/// A pass that does profile-guided sinking of instructions into loops.
+///
+/// This is a function pass as it shouldn't be composed into any kind of
+/// unified loop pass pipeline. The goal of it is to sink code into loops that
+/// is loop invariant but only required within the loop body when doing so
+/// reduces the global expected dynamic frequency with which it executes.
+/// A classic example is an extremely cold branch within a loop body.
+///
+/// We do this as a separate pass so that during normal optimization all
+/// invariant operations can be held outside the loop body to simplify
+/// fundamental analyses and transforms of the loop.
+class LoopSinkPass : public PassInfoMixin<LoopSinkPass> {
+public:
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &FAM);
+};
+}
+
+#endif // LLVM_TRANSFORMS_SCALAR_LOOPSINK_H