1 //====----- MachineBlockFrequencyInfo.h - MachineBlock Frequency Analysis ----====//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Loops should be simplified before this analysis.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CODEGEN_MACHINEBLOCKFREQUENCYINFO_H
15 #define LLVM_CODEGEN_MACHINEBLOCKFREQUENCYINFO_H
17 #include "llvm/CodeGen/MachineFunctionPass.h"
22 class MachineBranchProbabilityInfo;
23 template<class BlockT, class FunctionT, class BranchProbInfoT>
24 class BlockFrequencyImpl;
26 /// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate
27 /// machine basic block frequencies.
28 class MachineBlockFrequencyInfo : public MachineFunctionPass {
30 BlockFrequencyImpl<MachineBasicBlock, MachineFunction, MachineBranchProbabilityInfo> *MBFI;
35 MachineBlockFrequencyInfo();
37 ~MachineBlockFrequencyInfo();
39 void getAnalysisUsage(AnalysisUsage &AU) const;
41 bool runOnMachineFunction(MachineFunction &F);
43 /// getblockFreq - Return block frequency. Return 0 if we don't have the
44 /// information. Please note that initial frequency is equal to 1024. It means
45 /// that we should not rely on the value itself, but only on the comparison to
46 /// the other block frequencies. We do this to avoid using of floating points.
48 uint32_t getBlockFreq(MachineBasicBlock *MBB);