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 21 namespace llvm { 22 23 class MachineBasicBlock; 24 class MachineBranchProbabilityInfo; 25 template<class BlockT, class FunctionT, class BranchProbInfoT> 26 class BlockFrequencyImpl; 27 28 /// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate 29 /// machine basic block frequencies. 30 class MachineBlockFrequencyInfo : public MachineFunctionPass { 31 32 BlockFrequencyImpl<MachineBasicBlock, MachineFunction, 33 MachineBranchProbabilityInfo> *MBFI; 34 35 public: 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