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,
  43            std::function<const TargetLibraryInfo &(Function &F)> GetTLI);
  44
  45 private:
  46   InstrProfOptions Options;
  47   Module *M;
  48   Triple TT;
  49   std::function<const TargetLibraryInfo &(Function &F)> GetTLI;
  50   struct PerFunctionProfileData {
  51     uint32_t NumValueSites[IPVK_Last + 1];
  52     GlobalVariable *RegionCounters = nullptr;
  53     GlobalVariable *DataVar = nullptr;
  54
  55     PerFunctionProfileData() {
  56       memset(NumValueSites, 0, sizeof(uint32_t) * (IPVK_Last + 1));
  57     }
  58   };
  59   DenseMap<GlobalVariable *, PerFunctionProfileData> ProfileDataMap;
  60   std::vector<GlobalValue *> UsedVars;
  61   std::vector<GlobalVariable *> ReferencedNames;
  62   GlobalVariable *NamesVar;
  63   size_t NamesSize;
  64
  65   // Is this lowering for the context-sensitive instrumentation.
  66   bool IsCS;
  67
  68   // vector of counter load/store pairs to be register promoted.
  69   std::vector<LoadStorePair> PromotionCandidates;
  70
  71   // The start value of precise value profile range for memory intrinsic sizes.
  72   int64_t MemOPSizeRangeStart;
  73   // The end value of precise value profile range for memory intrinsic sizes.
  74   int64_t MemOPSizeRangeLast;
  75
  76   int64_t TotalCountersPromoted = 0;
  77
  78   /// Lower instrumentation intrinsics in the function. Returns true if there
  79   /// any lowering.
  80   bool lowerIntrinsics(Function *F);
  81
  82   /// Register-promote counter loads and stores in loops.
  83   void promoteCounterLoadStores(Function *F);
  84
  85   /// Returns true if profile counter update register promotion is enabled.
  86   bool isCounterPromotionEnabled() const;
  87
  88   /// Count the number of instrumented value sites for the function.
  89   void computeNumValueSiteCounts(InstrProfValueProfileInst *Ins);
  90
  91   /// Replace instrprof_value_profile with a call to runtime library.
  92   void lowerValueProfileInst(InstrProfValueProfileInst *Ins);
  93
  94   /// Replace instrprof_increment with an increment of the appropriate value.
  95   void lowerIncrement(InstrProfIncrementInst *Inc);
  96
  97   /// Force emitting of name vars for unused functions.
  98   void lowerCoverageData(GlobalVariable *CoverageNamesVar);
  99
 100   /// Get the region counters for an increment, creating them if necessary.
 101   ///
 102   /// If the counter array doesn't yet exist, the profile data variables
 103   /// referring to them will also be created.
 104   GlobalVariable *getOrCreateRegionCounters(InstrProfIncrementInst *Inc);
 105
 106   /// Emit the section with compressed function names.
 107   void emitNameData();
 108
 109   /// Emit value nodes section for value profiling.
 110   void emitVNodes();
 111
 112   /// Emit runtime registration functions for each profile data variable.
 113   void emitRegistration();
 114
 115   /// Emit the necessary plumbing to pull in the runtime initialization.
 116   /// Returns true if a change was made.
 117   bool emitRuntimeHook();
 118
 119   /// Add uses of our data variables and runtime hook.
 120   void emitUses();
 121
 122   /// Create a static initializer for our data, on platforms that need it,
 123   /// and for any profile output file that was specified.
 124   void emitInitialization();
 125 };
 126
 127 } // end namespace llvm
 128
 129 #endif // LLVM_TRANSFORMS_INSTRPROFILING_H