1 //===- InstrProfWriter.h - Instrumented profiling writer --------*- 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 // 9 // This file contains support for writing profiling data for instrumentation 10 // based PGO and coverage. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_PROFILEDATA_INSTRPROFWRITER_H 15 #define LLVM_PROFILEDATA_INSTRPROFWRITER_H 16 17 #include "llvm/ADT/DenseMap.h" 18 #include "llvm/ADT/MapVector.h" 19 #include "llvm/ADT/StringMap.h" 20 #include "llvm/IR/GlobalValue.h" 21 #include "llvm/Object/BuildID.h" 22 #include "llvm/ProfileData/InstrProf.h" 23 #include "llvm/ProfileData/MemProf.h" 24 #include "llvm/Support/Error.h" 25 #include <cstdint> 26 #include <memory> 27 #include <random> 28 29 namespace llvm { 30 31 /// Writer for instrumentation based profile data. 32 class InstrProfRecordWriterTrait; 33 class ProfOStream; 34 class MemoryBuffer; 35 class raw_fd_ostream; 36 37 class InstrProfWriter { 38 public: 39 using ProfilingData = SmallDenseMap<uint64_t, InstrProfRecord>; 40 41 private: 42 bool Sparse; 43 StringMap<ProfilingData> FunctionData; 44 /// The maximum length of a single temporal profile trace. 45 uint64_t MaxTemporalProfTraceLength; 46 /// The maximum number of stored temporal profile traces. 47 uint64_t TemporalProfTraceReservoirSize; 48 /// The total number of temporal profile traces seen. 49 uint64_t TemporalProfTraceStreamSize = 0; 50 /// The list of temporal profile traces. 51 SmallVector<TemporalProfTraceTy> TemporalProfTraces; 52 std::mt19937 RNG; 53 54 // A map to hold memprof data per function. The lower 64 bits obtained from 55 // the md5 hash of the function name is used to index into the map. 56 llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord> 57 MemProfRecordData; 58 // A map to hold frame id to frame mappings. The mappings are used to 59 // convert IndexedMemProfRecord to MemProfRecords with frame information 60 // inline. 61 llvm::MapVector<memprof::FrameId, memprof::Frame> MemProfFrameData; 62 63 // List of binary ids. 64 std::vector<llvm::object::BuildID> BinaryIds; 65 66 // An enum describing the attributes of the profile. 67 InstrProfKind ProfileKind = InstrProfKind::Unknown; 68 // Use raw pointer here for the incomplete type object. 69 InstrProfRecordWriterTrait *InfoObj; 70 71 public: 72 InstrProfWriter(bool Sparse = false, 73 uint64_t TemporalProfTraceReservoirSize = 0, 74 uint64_t MaxTemporalProfTraceLength = 0); 75 ~InstrProfWriter(); 76 getProfileData()77 StringMap<ProfilingData> &getProfileData() { return FunctionData; } 78 79 /// Add function counts for the given function. If there are already counts 80 /// for this function and the hash and number of counts match, each counter is 81 /// summed. Optionally scale counts by \p Weight. 82 void addRecord(NamedInstrProfRecord &&I, uint64_t Weight, 83 function_ref<void(Error)> Warn); addRecord(NamedInstrProfRecord && I,function_ref<void (Error)> Warn)84 void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) { 85 addRecord(std::move(I), 1, Warn); 86 } 87 88 /// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the 89 /// total number of temporal profiling traces the source has seen. 90 void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces, 91 uint64_t SrcStreamSize); 92 93 /// Add a memprof record for a function identified by its \p Id. 94 void addMemProfRecord(const GlobalValue::GUID Id, 95 const memprof::IndexedMemProfRecord &Record); 96 97 /// Add a memprof frame identified by the hash of the contents of the frame in 98 /// \p FrameId. 99 bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F, 100 function_ref<void(Error)> Warn); 101 102 // Add a binary id to the binary ids list. 103 void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs); 104 105 /// Merge existing function counts from the given writer. 106 void mergeRecordsFromWriter(InstrProfWriter &&IPW, 107 function_ref<void(Error)> Warn); 108 109 /// Write the profile to \c OS 110 Error write(raw_fd_ostream &OS); 111 112 /// Write the profile to a string output stream \c OS 113 Error write(raw_string_ostream &OS); 114 115 /// Write the profile in text format to \c OS 116 Error writeText(raw_fd_ostream &OS); 117 118 /// Write temporal profile trace data to the header in text format to \c OS 119 void writeTextTemporalProfTraceData(raw_fd_ostream &OS, 120 InstrProfSymtab &Symtab); 121 122 Error validateRecord(const InstrProfRecord &Func); 123 124 /// Write \c Record in text format to \c OS 125 static void writeRecordInText(StringRef Name, uint64_t Hash, 126 const InstrProfRecord &Counters, 127 InstrProfSymtab &Symtab, raw_fd_ostream &OS); 128 129 /// Write the profile, returning the raw data. For testing. 130 std::unique_ptr<MemoryBuffer> writeBuffer(); 131 132 /// Update the attributes of the current profile from the attributes 133 /// specified. An error is returned if IR and FE profiles are mixed. mergeProfileKind(const InstrProfKind Other)134 Error mergeProfileKind(const InstrProfKind Other) { 135 // If the kind is unset, this is the first profile we are merging so just 136 // set it to the given type. 137 if (ProfileKind == InstrProfKind::Unknown) { 138 ProfileKind = Other; 139 return Error::success(); 140 } 141 142 // Returns true if merging is should fail assuming A and B are incompatible. 143 auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) { 144 return (static_cast<bool>(ProfileKind & A) && 145 static_cast<bool>(Other & B)) || 146 (static_cast<bool>(ProfileKind & B) && 147 static_cast<bool>(Other & A)); 148 }; 149 150 // Check if the profiles are in-compatible. Clang frontend profiles can't be 151 // merged with other profile types. 152 if (static_cast<bool>( 153 (ProfileKind & InstrProfKind::FrontendInstrumentation) ^ 154 (Other & InstrProfKind::FrontendInstrumentation))) { 155 return make_error<InstrProfError>(instrprof_error::unsupported_version); 156 } 157 if (testIncompatible(InstrProfKind::FunctionEntryOnly, 158 InstrProfKind::FunctionEntryInstrumentation)) { 159 return make_error<InstrProfError>( 160 instrprof_error::unsupported_version, 161 "cannot merge FunctionEntryOnly profiles and BB profiles together"); 162 } 163 164 // Now we update the profile type with the bits that are set. 165 ProfileKind |= Other; 166 return Error::success(); 167 } 168 getProfileKind()169 InstrProfKind getProfileKind() const { return ProfileKind; } 170 171 // Internal interface for testing purpose only. 172 void setValueProfDataEndianness(llvm::endianness Endianness); 173 void setOutputSparse(bool Sparse); 174 // Compute the overlap b/w this object and Other. Program level result is 175 // stored in Overlap and function level result is stored in FuncLevelOverlap. 176 void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap, 177 OverlapStats &FuncLevelOverlap, 178 const OverlapFuncFilters &FuncFilter); 179 180 private: 181 void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I, 182 uint64_t Weight, function_ref<void(Error)> Warn); 183 bool shouldEncodeData(const ProfilingData &PD); 184 /// Add \p Trace using reservoir sampling. 185 void addTemporalProfileTrace(TemporalProfTraceTy Trace); 186 187 Error writeImpl(ProfOStream &OS); 188 }; 189 190 } // end namespace llvm 191 192 #endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H 193