1//====----- MachineBlockFrequencyInfo.h - MachineBlock Frequency Analysis ----====//
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 FunctionT, class BranchProbInfoT>
26class BlockFrequencyImpl;
27
28/// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate
29/// machine basic block frequencies.
30class MachineBlockFrequencyInfo : public MachineFunctionPass {
31
32  BlockFrequencyImpl<MachineBasicBlock, MachineFunction,
33                     MachineBranchProbabilityInfo> *MBFI;
34
35public:
36  static char ID;
37
38  MachineBlockFrequencyInfo();
39
40  ~MachineBlockFrequencyInfo();
41
42  void getAnalysisUsage(AnalysisUsage &AU) const;
43
44  bool runOnMachineFunction(MachineFunction &F);
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
54}
55
56#endif
57