1 //===- IndirectCallPromotionAnalysis.h - Indirect call analysis -*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 /// \file 9 /// Interface to identify indirect call promotion candidates. 10 /// 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_ANALYSIS_INDIRECTCALLPROMOTIONANALYSIS_H 14 #define LLVM_ANALYSIS_INDIRECTCALLPROMOTIONANALYSIS_H 15 16 #include "llvm/ProfileData/InstrProf.h" 17 18 namespace llvm { 19 20 class Instruction; 21 22 // Class for identifying profitable indirect call promotion candidates when 23 // the indirect-call value profile metadata is available. 24 class ICallPromotionAnalysis { 25 private: 26 // Allocate space to read the profile annotation. 27 std::unique_ptr<InstrProfValueData[]> ValueDataArray; 28 29 // Count is the call count for the direct-call target. 30 // TotalCount is the total call count for the indirect-call callsite. 31 // RemainingCount is the TotalCount minus promoted-direct-call count. 32 // Return true we should promote this indirect-call target. 33 bool isPromotionProfitable(uint64_t Count, uint64_t TotalCount, 34 uint64_t RemainingCount); 35 36 // Returns the number of profitable candidates to promote for the 37 // current ValueDataArray and the given \p Inst. 38 uint32_t getProfitablePromotionCandidates(const Instruction *Inst, 39 uint32_t NumVals, 40 uint64_t TotalCount); 41 42 // Noncopyable 43 ICallPromotionAnalysis(const ICallPromotionAnalysis &other) = delete; 44 ICallPromotionAnalysis & 45 operator=(const ICallPromotionAnalysis &other) = delete; 46 47 public: 48 ICallPromotionAnalysis(); 49 50 /// Returns reference to array of InstrProfValueData for the given 51 /// instruction \p I. 52 /// 53 /// The \p NumVals, \p TotalCount and \p NumCandidates 54 /// are set to the number of values in the array, the total profile count 55 /// of the indirect call \p I, and the number of profitable candidates 56 /// in the given array (which is sorted in reverse order of profitability). 57 /// 58 /// The returned array space is owned by this class, and overwritten on 59 /// subsequent calls. 60 ArrayRef<InstrProfValueData> 61 getPromotionCandidatesForInstruction(const Instruction *I, uint32_t &NumVals, 62 uint64_t &TotalCount, 63 uint32_t &NumCandidates); 64 }; 65 66 } // end namespace llvm 67 68 #endif 69