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_INSTRUMENTATION_INSTRPROFILING_H 14 #define LLVM_TRANSFORMS_INSTRUMENTATION_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 *> CompilerUsedVars; 61 std::vector<GlobalValue *> UsedVars; 62 std::vector<GlobalVariable *> ReferencedNames; 63 GlobalVariable *NamesVar; 64 size_t NamesSize; 65 66 // Is this lowering for the context-sensitive instrumentation. 67 bool IsCS; 68 69 // vector of counter load/store pairs to be register promoted. 70 std::vector<LoadStorePair> PromotionCandidates; 71 72 int64_t TotalCountersPromoted = 0; 73 74 /// Lower instrumentation intrinsics in the function. Returns true if there 75 /// any lowering. 76 bool lowerIntrinsics(Function *F); 77 78 /// Register-promote counter loads and stores in loops. 79 void promoteCounterLoadStores(Function *F); 80 81 /// Returns true if relocating counters at runtime is enabled. 82 bool isRuntimeCounterRelocationEnabled() const; 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_INSTRUMENTATION_INSTRPROFILING_H 129