diff options
Diffstat (limited to 'contrib/llvm/include/llvm/CodeGen/LazyMachineBlockFrequencyInfo.h')
-rw-r--r-- | contrib/llvm/include/llvm/CodeGen/LazyMachineBlockFrequencyInfo.h | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/contrib/llvm/include/llvm/CodeGen/LazyMachineBlockFrequencyInfo.h b/contrib/llvm/include/llvm/CodeGen/LazyMachineBlockFrequencyInfo.h new file mode 100644 index 000000000000..848ee1dc0dc6 --- /dev/null +++ b/contrib/llvm/include/llvm/CodeGen/LazyMachineBlockFrequencyInfo.h @@ -0,0 +1,76 @@ +///===- LazyMachineBlockFrequencyInfo.h - Lazy Block Frequency -*- C++ -*--===// +/// +/// The LLVM Compiler Infrastructure +/// +/// This file is distributed under the University of Illinois Open Source +/// License. See LICENSE.TXT for details. +/// +///===---------------------------------------------------------------------===// +/// \file +/// This is an alternative analysis pass to MachineBlockFrequencyInfo. The +/// difference is that with this pass the block frequencies are not computed +/// when the analysis pass is executed but rather when the BFI result is +/// explicitly requested by the analysis client. +/// +///===---------------------------------------------------------------------===// + +#ifndef LLVM_ANALYSIS_LAZYMACHINEBLOCKFREQUENCYINFO_H +#define LLVM_ANALYSIS_LAZYMACHINEBLOCKFREQUENCYINFO_H + +#include "llvm/CodeGen/MachineBlockFrequencyInfo.h" +#include "llvm/CodeGen/MachineBranchProbabilityInfo.h" +#include "llvm/CodeGen/MachineDominators.h" +#include "llvm/CodeGen/MachineLoopInfo.h" + +namespace llvm { +/// \brief This is an alternative analysis pass to MachineBlockFrequencyInfo. +/// The difference is that with this pass, the block frequencies are not +/// computed when the analysis pass is executed but rather when the BFI result +/// is explicitly requested by the analysis client. +/// +/// This works by checking querying if MBFI is available and otherwise +/// generating MBFI on the fly. In this case the passes required for (LI, DT) +/// are also queried before being computed on the fly. +/// +/// Note that it is expected that we wouldn't need this functionality for the +/// new PM since with the new PM, analyses are executed on demand. + +class LazyMachineBlockFrequencyInfoPass : public MachineFunctionPass { +private: + /// If generated on the fly this own the instance. + mutable std::unique_ptr<MachineBlockFrequencyInfo> OwnedMBFI; + + /// If generated on the fly this own the instance. + mutable std::unique_ptr<MachineLoopInfo> OwnedMLI; + + /// If generated on the fly this own the instance. + mutable std::unique_ptr<MachineDominatorTree> OwnedMDT; + + /// The function. + MachineFunction *MF = nullptr; + + /// \brief Calculate MBFI and all other analyses that's not available and + /// required by BFI. + MachineBlockFrequencyInfo &calculateIfNotAvailable() const; + +public: + static char ID; + + LazyMachineBlockFrequencyInfoPass(); + + /// \brief Compute and return the block frequencies. + MachineBlockFrequencyInfo &getBFI() { return calculateIfNotAvailable(); } + + /// \brief Compute and return the block frequencies. + const MachineBlockFrequencyInfo &getBFI() const { + return calculateIfNotAvailable(); + } + + void getAnalysisUsage(AnalysisUsage &AU) const override; + + bool runOnMachineFunction(MachineFunction &F) override; + void releaseMemory() override; + void print(raw_ostream &OS, const Module *M) const override; +}; +} +#endif |