1//===- MachineBlockFrequencyInfo.h - MBB Frequency Analysis -*- C++ -*-----===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// Loops should be simplified before this analysis.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CODEGEN_MACHINEBLOCKFREQUENCYINFO_H
15#define LLVM_CODEGEN_MACHINEBLOCKFREQUENCYINFO_H
16
17#include "llvm/CodeGen/MachineFunctionPass.h"
18#include "llvm/Support/BlockFrequency.h"
19#include <climits>
20
21namespace llvm {
22
23class MachineBasicBlock;
24class MachineBranchProbabilityInfo;
25template <class BlockT> class BlockFrequencyInfoImpl;
26
27/// MachineBlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation
28/// to estimate machine basic block frequencies.
29class MachineBlockFrequencyInfo : public MachineFunctionPass {
30  typedef BlockFrequencyInfoImpl<MachineBasicBlock> ImplType;
31  std::unique_ptr<ImplType> MBFI;
32
33public:
34  static char ID;
35
36  MachineBlockFrequencyInfo();
37
38  ~MachineBlockFrequencyInfo();
39
40  void getAnalysisUsage(AnalysisUsage &AU) const override;
41
42  bool runOnMachineFunction(MachineFunction &F) override;
43
44  void releaseMemory() override;
45
46  /// getblockFreq - Return block frequency. Return 0 if we don't have the
47  /// information. Please note that initial frequency is equal to 1024. It means
48  /// that we should not rely on the value itself, but only on the comparison to
49  /// the other block frequencies. We do this to avoid using of floating points.
50  ///
51  BlockFrequency getBlockFreq(const MachineBasicBlock *MBB) const;
52
53  const MachineFunction *getFunction() const;
54  void view() const;
55
56  // Print the block frequency Freq to OS using the current functions entry
57  // frequency to convert freq into a relative decimal form.
58  raw_ostream &printBlockFreq(raw_ostream &OS, const BlockFrequency Freq) const;
59
60  // Convenience method that attempts to look up the frequency associated with
61  // BB and print it to OS.
62  raw_ostream &printBlockFreq(raw_ostream &OS,
63                              const MachineBasicBlock *MBB) const;
64
65  uint64_t getEntryFreq() const;
66
67};
68
69}
70
71#endif
72