1//===- LoopSink.h - Loop Sink Pass ------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file provides the interface for the Loop Sink pass.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
14#define LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
15
16#include "llvm/IR/PassManager.h"
17
18namespace llvm {
19
20class Function;
21
22/// A pass that does profile-guided sinking of instructions into loops.
23///
24/// This is a function pass as it shouldn't be composed into any kind of
25/// unified loop pass pipeline. The goal of it is to sink code into loops that
26/// is loop invariant but only required within the loop body when doing so
27/// reduces the global expected dynamic frequency with which it executes.
28/// A classic example is an extremely cold branch within a loop body.
29///
30/// We do this as a separate pass so that during normal optimization all
31/// invariant operations can be held outside the loop body to simplify
32/// fundamental analyses and transforms of the loop.
33class LoopSinkPass : public PassInfoMixin<LoopSinkPass> {
34public:
35 PreservedAnalyses run(Function &F, FunctionAnalysisManager &FAM);
36};
37}
38
39#endif // LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
40

source code of llvm/include/llvm/Transforms/Scalar/LoopSink.h