xref: /freebsd-10.1-release/contrib/llvm/include/llvm/Analysis/BlockFrequencyInfo.h

//===------- BlockFrequencyInfo.h - Block Frequency Analysis --*- C++ -*---===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Loops should be simplified before this analysis.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H
#define LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H

#include "llvm/Pass.h"
#include "llvm/Support/BlockFrequency.h"
#include <climits>

namespace llvm {

class BranchProbabilityInfo;
template<class BlockT, class FunctionT, class BranchProbInfoT>
class BlockFrequencyImpl;

/// BlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate
/// IR basic block frequencies.
class BlockFrequencyInfo : public FunctionPass {

  BlockFrequencyImpl<BasicBlock, Function, BranchProbabilityInfo> *BFI;

public:
  static char ID;

  BlockFrequencyInfo();

  ~BlockFrequencyInfo();

  void getAnalysisUsage(AnalysisUsage &AU) const;

  bool runOnFunction(Function &F);
  void print(raw_ostream &O, const Module *M) const;
  const Function *getFunction() const;
  void view() const;

  /// getblockFreq - Return block frequency. Return 0 if we don't have the
  /// information. Please note that initial frequency is equal to ENTRY_FREQ. It
  /// means that we should not rely on the value itself, but only on the
  /// comparison to the other block frequencies. We do this to avoid using of
  /// floating points.
  BlockFrequency getBlockFreq(const BasicBlock *BB) const;
};

}

#endif