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 MachineBranchProbabilityInfo; 24 template<class BlockT, class FunctionT, class BranchProbInfoT> 25 class BlockFrequencyImpl; 26 27 /// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate 28 /// machine basic block frequencies. 29 class MachineBlockFrequencyInfo : public MachineFunctionPass { 30 31 BlockFrequencyImpl<MachineBasicBlock, MachineFunction, MachineBranchProbabilityInfo> *MBFI; 32 33 public: 34 static char ID; 35 36 MachineBlockFrequencyInfo(); 37 38 ~MachineBlockFrequencyInfo(); 39 40 void getAnalysisUsage(AnalysisUsage &AU) const; 41 42 bool runOnMachineFunction(MachineFunction &F); 43 44 /// getblockFreq - Return block frequency. Return 0 if we don't have the 45 /// information. Please note that initial frequency is equal to 1024. It means 46 /// that we should not rely on the value itself, but only on the comparison to 47 /// the other block frequencies. We do this to avoid using of floating points. 48 /// 49 BlockFrequency getBlockFreq(MachineBasicBlock *MBB) const; 50 }; 51 52 } 53 54 #endif 55
