include/llvm/Transforms/Instrumentation/InstrProfiling.h

   1 //===- Transforms/Instrumentation/InstrProfiling.h --------------*- 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 /// This file provides the interface for LLVM's PGO Instrumentation lowering
  10 /// pass.
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_TRANSFORMS_INSTRPROFILING_H
  14 #define LLVM_TRANSFORMS_INSTRPROFILING_H
  15
  16 #include "llvm/ADT/DenseMap.h"
  17 #include "llvm/ADT/StringRef.h"
  18 #include "llvm/IR/IntrinsicInst.h"
  19 #include "llvm/IR/PassManager.h"
  20 #include "llvm/ProfileData/InstrProf.h"
  21 #include "llvm/Transforms/Instrumentation.h"
  22 #include <cstddef>
  23 #include <cstdint>
  24 #include <cstring>
  25 #include <vector>
  26
  27 namespace llvm {
  28
  29 class TargetLibraryInfo;
  30 using LoadStorePair = std::pair<Instruction *, Instruction *>;
  31
  32 /// Instrumentation based profiling lowering pass. This pass lowers
  33 /// the profile instrumented code generated by FE or the IR based
  34 /// instrumentation pass.
  35 class InstrProfiling : public PassInfoMixin<InstrProfiling> {
  36 public:
  37   InstrProfiling() : IsCS(false) {}
  38   InstrProfiling(const InstrProfOptions &Options, bool IsCS = false)
  39       : Options(Options), IsCS(IsCS) {}
  40
  41   PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
  42   bool run(Module &M, const TargetLibraryInfo &TLI);
  43
  44 private:
  45   InstrProfOptions Options;
  46   Module *M;
  47   Triple TT;
  48   const TargetLibraryInfo *TLI;
  49   struct PerFunctionProfileData {
  50     uint32_t NumValueSites[IPVK_Last + 1];
  51     GlobalVariable *RegionCounters = nullptr;
  52     GlobalVariable *DataVar = nullptr;
  53
  54     PerFunctionProfileData() {
  55       memset(NumValueSites, 0, sizeof(uint32_t) * (IPVK_Last + 1));
  56     }
  57   };
  58   DenseMap<GlobalVariable *, PerFunctionProfileData> ProfileDataMap;
  59   std::vector<GlobalValue *> UsedVars;
  60   std::vector<GlobalVariable *> ReferencedNames;
  61   GlobalVariable *NamesVar;
  62   size_t NamesSize;
  63
  64   // Is this lowering for the context-sensitive instrumentation.
  65   bool IsCS;
  66
  67   // vector of counter load/store pairs to be register promoted.
  68   std::vector<LoadStorePair> PromotionCandidates;
  69
  70   // The start value of precise value profile range for memory intrinsic sizes.
  71   int64_t MemOPSizeRangeStart;
  72   // The end value of precise value profile range for memory intrinsic sizes.
  73   int64_t MemOPSizeRangeLast;
  74
  75   int64_t TotalCountersPromoted = 0;
  76
  77   /// Lower instrumentation intrinsics in the function. Returns true if there
  78   /// any lowering.
  79   bool lowerIntrinsics(Function *F);
  80
  81   /// Register-promote counter loads and stores in loops.
  82   void promoteCounterLoadStores(Function *F);
  83
  84   /// Returns true if profile counter update register promotion is enabled.
  85   bool isCounterPromotionEnabled() const;
  86
  87   /// Count the number of instrumented value sites for the function.
  88   void computeNumValueSiteCounts(InstrProfValueProfileInst *Ins);
  89
  90   /// Replace instrprof_value_profile with a call to runtime library.
  91   void lowerValueProfileInst(InstrProfValueProfileInst *Ins);
  92
  93   /// Replace instrprof_increment with an increment of the appropriate value.
  94   void lowerIncrement(InstrProfIncrementInst *Inc);
  95
  96   /// Force emitting of name vars for unused functions.
  97   void lowerCoverageData(GlobalVariable *CoverageNamesVar);
  98
  99   /// Get the region counters for an increment, creating them if necessary.
 100   ///
 101   /// If the counter array doesn't yet exist, the profile data variables
 102   /// referring to them will also be created.
 103   GlobalVariable *getOrCreateRegionCounters(InstrProfIncrementInst *Inc);
 104
 105   /// Emit the section with compressed function names.
 106   void emitNameData();
 107
 108   /// Emit value nodes section for value profiling.
 109   void emitVNodes();
 110
 111   /// Emit runtime registration functions for each profile data variable.
 112   void emitRegistration();
 113
 114   /// Emit the necessary plumbing to pull in the runtime initialization.
 115   /// Returns true if a change was made.
 116   bool emitRuntimeHook();
 117
 118   /// Add uses of our data variables and runtime hook.
 119   void emitUses();
 120
 121   /// Create a static initializer for our data, on platforms that need it,
 122   /// and for any profile output file that was specified.
 123   void emitInitialization();
 124 };
 125
 126 } // end namespace llvm
 127
 128 #endif // LLVM_TRANSFORMS_INSTRPROFILING_H