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 class LoopInfo; 25 template <class BlockT> class BlockFrequencyInfoImpl; 26 27 /// BlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to 28 /// estimate IR basic block frequencies. 29 class BlockFrequencyInfo { 30 typedef BlockFrequencyInfoImpl<BasicBlock> ImplType; 31 std::unique_ptr<ImplType> BFI; 32 33 public: 34 BlockFrequencyInfo(); 35 BlockFrequencyInfo(const Function &F, const BranchProbabilityInfo &BPI, 36 const LoopInfo &LI); 37 38 const Function *getFunction() const; 39 void view() const; 40 41 /// getblockFreq - Return block frequency. Return 0 if we don't have the 42 /// information. Please note that initial frequency is equal to ENTRY_FREQ. It 43 /// means that we should not rely on the value itself, but only on the 44 /// comparison to the other block frequencies. We do this to avoid using of 45 /// floating points. 46 BlockFrequency getBlockFreq(const BasicBlock *BB) const; 47 48 // Set the frequency of the given basic block. 49 void setBlockFreq(const BasicBlock *BB, uint64_t Freq); 50 51 /// calculate - compute block frequency info for the given function. 52 void calculate(const Function &F, const BranchProbabilityInfo &BPI, 53 const LoopInfo &LI); 54 55 // Print the block frequency Freq to OS using the current functions entry 56 // frequency to convert freq into a relative decimal form. 57 raw_ostream &printBlockFreq(raw_ostream &OS, const BlockFrequency Freq) const; 58 59 // Convenience method that attempts to look up the frequency associated with 60 // BB and print it to OS. 61 raw_ostream &printBlockFreq(raw_ostream &OS, const BasicBlock *BB) const; 62 63 uint64_t getEntryFreq() const; 64 void releaseMemory(); 65 void print(raw_ostream &OS) const; 66 }; 67 68 /// \brief Legacy analysis pass which computes \c BlockFrequencyInfo. 69 class BlockFrequencyInfoWrapperPass : public FunctionPass { 70 BlockFrequencyInfo BFI; 71 72 public: 73 static char ID; 74 75 BlockFrequencyInfoWrapperPass(); 76 ~BlockFrequencyInfoWrapperPass() override; 77 78 BlockFrequencyInfo &getBFI() { return BFI; } 79 const BlockFrequencyInfo &getBFI() const { return BFI; } 80 81 void getAnalysisUsage(AnalysisUsage &AU) const override; 82 83 bool runOnFunction(Function &F) override; 84 void releaseMemory() override; 85 void print(raw_ostream &OS, const Module *M) const override; 86 }; 87 88 } 89 90 #endif 91
