Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- IndirectCallPromotionAnalysis.h - Indirect call analysis -*- 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

//

//===----------------------------------------------------------------------===//

/// \file

/// Interface to identify indirect call promotion candidates.

///

//===----------------------------------------------------------------------===//

#ifndef LLVM_ANALYSIS_INDIRECTCALLPROMOTIONANALYSIS_H

#define LLVM_ANALYSIS_INDIRECTCALLPROMOTIONANALYSIS_H

#include "llvm/ProfileData/InstrProf.h"

namespace llvm {

class Instruction;

// Class for identifying profitable indirect call promotion candidates when

// the indirect-call value profile metadata is available.

class ICallPromotionAnalysis {

private:

  // Allocate space to read the profile annotation.

  std::unique_ptr<InstrProfValueData[]> ValueDataArray;

  // Count is the call count for the direct-call target.

  // TotalCount is the total call count for the indirect-call callsite.

  // RemainingCount is the TotalCount minus promoted-direct-call count.

  // Return true we should promote this indirect-call target.

  bool isPromotionProfitable(uint64_t Count, uint64_t TotalCount,

                             uint64_t RemainingCount);

  // Returns the number of profitable candidates to promote for the

  // current ValueDataArray and the given \p Inst.

  uint32_t getProfitablePromotionCandidates(const Instruction *Inst,

                                            uint32_t NumVals,

                                            uint64_t TotalCount);

  // Noncopyable

  ICallPromotionAnalysis(const ICallPromotionAnalysis &other) = delete;

  ICallPromotionAnalysis &

  operator=(const ICallPromotionAnalysis &other) = delete;

public:

  ICallPromotionAnalysis();

  /// Returns reference to array of InstrProfValueData for the given

  /// instruction \p I.

  ///

  /// The \p NumVals, \p TotalCount and \p NumCandidates

  /// are set to the number of values in the array, the total profile count

  /// of the indirect call \p I, and the number of profitable candidates

  /// in the given array (which is sorted in reverse order of profitability).

  ///

  /// The returned array space is owned by this class, and overwritten on

  /// subsequent calls.

  ArrayRef<InstrProfValueData>

  getPromotionCandidatesForInstruction(const Instruction *I, uint32_t &NumVals,

                                       uint64_t &TotalCount,

                                       uint32_t &NumCandidates);

};

} // end namespace llvm

#endif