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() = default;
  38   InstrProfiling(const InstrProfOptions &Options) : Options(Options) {}
  39
  40   PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
  41   bool run(Module &M, const TargetLibraryInfo &TLI);
  42
  43 private:
  44   InstrProfOptions Options;
  45   Module *M;
  46   Triple TT;
  47   const TargetLibraryInfo *TLI;
  48   struct PerFunctionProfileData {
  49     uint32_t NumValueSites[IPVK_Last + 1];
  50     GlobalVariable *RegionCounters = nullptr;
  51     GlobalVariable *DataVar = nullptr;
  52
  53     PerFunctionProfileData() {
  54       memset(NumValueSites, 0, sizeof(uint32_t) * (IPVK_Last + 1));
  55     }
  56   };
  57   DenseMap<GlobalVariable *, PerFunctionProfileData> ProfileDataMap;
  58   std::vector<GlobalValue *> UsedVars;
  59   std::vector<GlobalVariable *> ReferencedNames;
  60   GlobalVariable *NamesVar;
  61   size_t NamesSize;
  62
  63   // vector of counter load/store pairs to be register promoted.
  64   std::vector<LoadStorePair> PromotionCandidates;
  65
  66   // The start value of precise value profile range for memory intrinsic sizes.
  67   int64_t MemOPSizeRangeStart;
  68   // The end value of precise value profile range for memory intrinsic sizes.
  69   int64_t MemOPSizeRangeLast;
  70
  71   int64_t TotalCountersPromoted = 0;
  72
  73   /// Lower instrumentation intrinsics in the function. Returns true if there
  74   /// any lowering.
  75   bool lowerIntrinsics(Function *F);
  76
  77   /// Register-promote counter loads and stores in loops.
  78   void promoteCounterLoadStores(Function *F);
  79
  80   /// Returns true if profile counter update register promotion is enabled.
  81   bool isCounterPromotionEnabled() const;
  82
  83   /// Count the number of instrumented value sites for the function.
  84   void computeNumValueSiteCounts(InstrProfValueProfileInst *Ins);
  85
  86   /// Replace instrprof_value_profile with a call to runtime library.
  87   void lowerValueProfileInst(InstrProfValueProfileInst *Ins);
  88
  89   /// Replace instrprof_increment with an increment of the appropriate value.
  90   void lowerIncrement(InstrProfIncrementInst *Inc);
  91
  92   /// Force emitting of name vars for unused functions.
  93   void lowerCoverageData(GlobalVariable *CoverageNamesVar);
  94
  95   /// Get the region counters for an increment, creating them if necessary.
  96   ///
  97   /// If the counter array doesn't yet exist, the profile data variables
  98   /// referring to them will also be created.
  99   GlobalVariable *getOrCreateRegionCounters(InstrProfIncrementInst *Inc);
 100
 101   /// Emit the section with compressed function names.
 102   void emitNameData();
 103
 104   /// Emit value nodes section for value profiling.
 105   void emitVNodes();
 106
 107   /// Emit runtime registration functions for each profile data variable.
 108   void emitRegistration();
 109
 110   /// Emit the necessary plumbing to pull in the runtime initialization.
 111   /// Returns true if a change was made.
 112   bool emitRuntimeHook();
 113
 114   /// Add uses of our data variables and runtime hook.
 115   void emitUses();
 116
 117   /// Create a static initializer for our data, on platforms that need it,
 118   /// and for any profile output file that was specified.
 119   void emitInitialization();
 120 };
 121
 122 } // end namespace llvm
 123
 124 #endif // LLVM_TRANSFORMS_INSTRPROFILING_H