BlockFrequencyInfo.h revision 6aa5c26c81071e22a23a6f0ae7dcac6080ad6597
1//========-------- BlockFrequencyInfo.h - Block 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_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 21namespace llvm { 22 23class BranchProbabilityInfo; 24template<class BlockT, class FunctionT, class BranchProbInfoT> 25class BlockFrequencyImpl; 26 27/// BlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate 28/// IR basic block frequencies. 29class BlockFrequencyInfo : public FunctionPass { 30 31 BlockFrequencyImpl<BasicBlock, Function, BranchProbabilityInfo> *BFI; 32 33public: 34 static char ID; 35 36 BlockFrequencyInfo(); 37 38 ~BlockFrequencyInfo(); 39 40 void getAnalysisUsage(AnalysisUsage &AU) const; 41 42 bool runOnFunction(Function &F); 43 void print(raw_ostream &O, const Module *M) const; 44 45 /// getblockFreq - Return block frequency. Return 0 if we don't have the 46 /// information. Please note that initial frequency is equal to 1024. It means 47 /// that we should not rely on the value itself, but only on the comparison to 48 /// the other block frequencies. We do this to avoid using of floating points. 49 /// 50 BlockFrequency getBlockFreq(BasicBlock *BB) const; 51}; 52 53} 54 55#endif 56