LLVM  10.0.0svn
IndirectCallPromotionAnalysis.h
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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 
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.
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;
45  operator=(const ICallPromotionAnalysis &other) = delete;
46 
47 public:
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.
62  uint64_t &TotalCount,
63  uint32_t &NumCandidates);
64 };
65 
66 } // end namespace llvm
67 
68 #endif
ArrayRef< InstrProfValueData > getPromotionCandidatesForInstruction(const Instruction *I, uint32_t &NumVals, uint64_t &TotalCount, uint32_t &NumCandidates)
Returns reference to array of InstrProfValueData for the given instruction I.
This class represents lattice values for constants.
Definition: AllocatorList.h:23
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
#define I(x, y, z)
Definition: MD5.cpp:58