llvm.org GIT mirror llvm / 9f998de include / llvm / CodeGen / MachineBlockFrequencyInfo.h

Tree @9f998de (Download .tar.gz)

MachineBlockFrequencyInfo.h @9f998deraw · history · blame

//====-- MachineBlockFrequencyInfo.h - MBB Frequency Analysis -*- C++ -*--====//
//                     The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// Loops should be simplified before this analysis.


#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/BlockFrequency.h"
#include <climits>

namespace llvm {

class MachineBasicBlock;
class MachineBranchProbabilityInfo;
template<class BlockT, class FunctionT, class BranchProbInfoT>
class BlockFrequencyImpl;

/// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate
/// machine basic block frequencies.
class MachineBlockFrequencyInfo : public MachineFunctionPass {

  BlockFrequencyImpl<MachineBasicBlock, MachineFunction,
                     MachineBranchProbabilityInfo> *MBFI;

  static char ID;



  void getAnalysisUsage(AnalysisUsage &AU) const override;

  bool runOnMachineFunction(MachineFunction &F) override;

  /// getblockFreq - Return block frequency. Return 0 if we don't have the
  /// information. Please note that initial frequency is equal to 1024. It means
  /// that we should not rely on the value itself, but only on the comparison to
  /// the other block frequencies. We do this to avoid using of floating points.
  BlockFrequency getBlockFreq(const MachineBasicBlock *MBB) const;

  MachineFunction *getFunction() const;
  void view() const;

  // Print the block frequency Freq to OS using the current functions entry
  // frequency to convert freq into a relative decimal form.
  raw_ostream &printBlockFreq(raw_ostream &OS, const BlockFrequency Freq) const;

  // Convenience method that attempts to look up the frequency associated with
  // BB and print it to OS.
  raw_ostream &printBlockFreq(raw_ostream &OS,
                              const MachineBasicBlock *MBB) const;

  uint64_t getEntryFreq() const;