| //===- 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 |
