LLVM  9.0.0svn
LoopSink.h
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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/Analysis/LoopInfo.h"
17 #include "llvm/IR/PassManager.h"
19 
20 namespace llvm {
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.
33 class LoopSinkPass : public PassInfoMixin<LoopSinkPass> {
34 public:
36 };
37 }
38 
39 #endif // LLVM_TRANSFORMS_SCALAR_LOOPSINK_H
This class represents lattice values for constants.
Definition: AllocatorList.h:23
This header provides classes for managing a pipeline of passes over loops in LLVM IR...
F(f)
A CRTP mix-in to automatically provide informational APIs needed for passes.
Definition: PassManager.h:372
A pass that does profile-guided sinking of instructions into loops.
Definition: LoopSink.h:33
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:153
A container for analyses that lazily runs them and caches their results.
This header defines various interfaces for pass management in LLVM.
PreservedAnalyses run(Function &F, FunctionAnalysisManager &FAM)
Definition: LoopSink.cpp:316