1317017Sdim///===- LazyMachineBlockFrequencyInfo.h - Lazy Block Frequency -*- C++ -*--===// 2317017Sdim/// 3353358Sdim/// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim/// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim/// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6317017Sdim/// 7317017Sdim///===---------------------------------------------------------------------===// 8317017Sdim/// \file 9317017Sdim/// This is an alternative analysis pass to MachineBlockFrequencyInfo. The 10317017Sdim/// difference is that with this pass the block frequencies are not computed 11317017Sdim/// when the analysis pass is executed but rather when the BFI result is 12317017Sdim/// explicitly requested by the analysis client. 13317017Sdim/// 14317017Sdim///===---------------------------------------------------------------------===// 15317017Sdim 16317017Sdim#ifndef LLVM_ANALYSIS_LAZYMACHINEBLOCKFREQUENCYINFO_H 17317017Sdim#define LLVM_ANALYSIS_LAZYMACHINEBLOCKFREQUENCYINFO_H 18317017Sdim 19317017Sdim#include "llvm/CodeGen/MachineBlockFrequencyInfo.h" 20317017Sdim#include "llvm/CodeGen/MachineBranchProbabilityInfo.h" 21317017Sdim#include "llvm/CodeGen/MachineDominators.h" 22317017Sdim#include "llvm/CodeGen/MachineLoopInfo.h" 23317017Sdim 24317017Sdimnamespace llvm { 25341825Sdim/// This is an alternative analysis pass to MachineBlockFrequencyInfo. 26317017Sdim/// The difference is that with this pass, the block frequencies are not 27317017Sdim/// computed when the analysis pass is executed but rather when the BFI result 28317017Sdim/// is explicitly requested by the analysis client. 29317017Sdim/// 30317017Sdim/// This works by checking querying if MBFI is available and otherwise 31317017Sdim/// generating MBFI on the fly. In this case the passes required for (LI, DT) 32317017Sdim/// are also queried before being computed on the fly. 33317017Sdim/// 34317017Sdim/// Note that it is expected that we wouldn't need this functionality for the 35317017Sdim/// new PM since with the new PM, analyses are executed on demand. 36317017Sdim 37317017Sdimclass LazyMachineBlockFrequencyInfoPass : public MachineFunctionPass { 38317017Sdimprivate: 39317017Sdim /// If generated on the fly this own the instance. 40317017Sdim mutable std::unique_ptr<MachineBlockFrequencyInfo> OwnedMBFI; 41317017Sdim 42317017Sdim /// If generated on the fly this own the instance. 43317017Sdim mutable std::unique_ptr<MachineLoopInfo> OwnedMLI; 44317017Sdim 45317017Sdim /// If generated on the fly this own the instance. 46317017Sdim mutable std::unique_ptr<MachineDominatorTree> OwnedMDT; 47317017Sdim 48317017Sdim /// The function. 49317017Sdim MachineFunction *MF = nullptr; 50317017Sdim 51341825Sdim /// Calculate MBFI and all other analyses that's not available and 52317017Sdim /// required by BFI. 53317017Sdim MachineBlockFrequencyInfo &calculateIfNotAvailable() const; 54317017Sdim 55317017Sdimpublic: 56317017Sdim static char ID; 57317017Sdim 58317017Sdim LazyMachineBlockFrequencyInfoPass(); 59317017Sdim 60341825Sdim /// Compute and return the block frequencies. 61317017Sdim MachineBlockFrequencyInfo &getBFI() { return calculateIfNotAvailable(); } 62317017Sdim 63341825Sdim /// Compute and return the block frequencies. 64317017Sdim const MachineBlockFrequencyInfo &getBFI() const { 65317017Sdim return calculateIfNotAvailable(); 66317017Sdim } 67317017Sdim 68317017Sdim void getAnalysisUsage(AnalysisUsage &AU) const override; 69317017Sdim 70317017Sdim bool runOnMachineFunction(MachineFunction &F) override; 71317017Sdim void releaseMemory() override; 72317017Sdim void print(raw_ostream &OS, const Module *M) const override; 73317017Sdim}; 74317017Sdim} 75317017Sdim#endif 76