1 //===- BlockFrequencyInfo.h - Block 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_ANALYSIS_BLOCKFREQUENCYINFO_H 15 #define LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H 16 17 #include "llvm/Pass.h" 18 #include "llvm/Support/BlockFrequency.h" 19 #include <climits> 20 21 namespace llvm { 22 23 class BranchProbabilityInfo; 24 template <class BlockT> class BlockFrequencyInfoImpl; 25 26 /// BlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to 27 /// estimate IR basic block frequencies. 28 class BlockFrequencyInfo : public FunctionPass { 29 typedef BlockFrequencyInfoImpl<BasicBlock> ImplType; 30 std::unique_ptr<ImplType> BFI; 31 32 public: 33 static char ID; 34 35 BlockFrequencyInfo(); 36 37 ~BlockFrequencyInfo(); 38 39 void getAnalysisUsage(AnalysisUsage &AU) const override; 40 41 bool runOnFunction(Function &F) override; 42 void releaseMemory() override; 43 void print(raw_ostream &O, const Module *M) const override; 44 const Function *getFunction() const; 45 void view() const; 46 47 /// getblockFreq - Return block frequency. Return 0 if we don't have the 48 /// information. Please note that initial frequency is equal to ENTRY_FREQ. It 49 /// means that we should not rely on the value itself, but only on the 50 /// comparison to the other block frequencies. We do this to avoid using of 51 /// floating points. 52 BlockFrequency getBlockFreq(const BasicBlock *BB) const; 53 54 // Print the block frequency Freq to OS using the current functions entry 55 // frequency to convert freq into a relative decimal form. 56 raw_ostream &printBlockFreq(raw_ostream &OS, const BlockFrequency Freq) const; 57 58 // Convenience method that attempts to look up the frequency associated with 59 // BB and print it to OS. 60 raw_ostream &printBlockFreq(raw_ostream &OS, const BasicBlock *BB) const; 61 62 uint64_t getEntryFreq() const; 63 64 }; 65 66 } 67 68 #endif 69
