llvm/llvm/include/llvm/Support/BranchProbability.h

//===- BranchProbability.h - Branch Probability Wrapper ---------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Definition of BranchProbability shared by IR and Machine Instructions.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_BRANCHPROBABILITY_H
#define LLVM_SUPPORT_BRANCHPROBABILITY_H

#include "llvm/Support/DataTypes.h"
#include <algorithm>
#include <cassert>
#include <iterator>
#include <numeric>

namespace llvm {

class raw_ostream;

// This class represents Branch Probability as a non-negative fraction that is
// no greater than 1. It uses a fixed-point-like implementation, in which the
// denominator is always a constant value (here we use 1<<31 for maximum
// precision).
class BranchProbability { … };

inline raw_ostream &operator<<(raw_ostream &OS, BranchProbability Prob) { … }

template <class ProbabilityIter>
void BranchProbability::normalizeProbabilities(ProbabilityIter Begin,
                                               ProbabilityIter End) { … }

}

#endif