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 // The MemProf data. 55 memprof::IndexedMemProfData MemProfData; 56 57 // List of binary ids. 58 std::vector<llvm::object::BuildID> BinaryIds; 59 60 // Read the vtable names from raw instr profile reader. 61 StringSet<> VTableNames; 62 63 // An enum describing the attributes of the profile. 64 InstrProfKind ProfileKind = InstrProfKind::Unknown; 65 // Use raw pointer here for the incomplete type object. 66 InstrProfRecordWriterTrait *InfoObj; 67 68 // Temporary support for writing the previous version of the format, to enable 69 // some forward compatibility. Currently this suppresses the writing of the 70 // new vtable names section and header fields. 71 // TODO: Consider enabling this with future version changes as well, to ease 72 // deployment of newer versions of llvm-profdata. 73 bool WritePrevVersion = false; 74 75 // The MemProf version we should write. 76 memprof::IndexedVersion MemProfVersionRequested; 77 78 // Whether to serialize the full schema. 79 bool MemProfFullSchema; 80 81 public: 82 InstrProfWriter( 83 bool Sparse = false, uint64_t TemporalProfTraceReservoirSize = 0, 84 uint64_t MaxTemporalProfTraceLength = 0, bool WritePrevVersion = false, 85 memprof::IndexedVersion MemProfVersionRequested = memprof::Version0, 86 bool MemProfFullSchema = false); 87 ~InstrProfWriter(); 88 getProfileData()89 StringMap<ProfilingData> &getProfileData() { return FunctionData; } 90 91 /// Add function counts for the given function. If there are already counts 92 /// for this function and the hash and number of counts match, each counter is 93 /// summed. Optionally scale counts by \p Weight. 94 void addRecord(NamedInstrProfRecord &&I, uint64_t Weight, 95 function_ref<void(Error)> Warn); addRecord(NamedInstrProfRecord && I,function_ref<void (Error)> Warn)96 void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) { 97 addRecord(std::move(I), 1, Warn); 98 } addVTableName(StringRef VTableName)99 void addVTableName(StringRef VTableName) { VTableNames.insert(VTableName); } 100 101 /// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the 102 /// total number of temporal profiling traces the source has seen. 103 void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces, 104 uint64_t SrcStreamSize); 105 106 /// Add a memprof record for a function identified by its \p Id. 107 void addMemProfRecord(const GlobalValue::GUID Id, 108 const memprof::IndexedMemProfRecord &Record); 109 110 /// Add a memprof frame identified by the hash of the contents of the frame in 111 /// \p FrameId. 112 bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F, 113 function_ref<void(Error)> Warn); 114 115 /// Add a call stack identified by the hash of the contents of the call stack 116 /// in \p CallStack. 117 bool addMemProfCallStack(const memprof::CallStackId CSId, 118 const llvm::SmallVector<memprof::FrameId> &CallStack, 119 function_ref<void(Error)> Warn); 120 121 // Add a binary id to the binary ids list. 122 void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs); 123 124 /// Merge existing function counts from the given writer. 125 void mergeRecordsFromWriter(InstrProfWriter &&IPW, 126 function_ref<void(Error)> Warn); 127 128 /// Write the profile to \c OS 129 Error write(raw_fd_ostream &OS); 130 131 /// Write the profile to a string output stream \c OS 132 Error write(raw_string_ostream &OS); 133 134 /// Write the profile in text format to \c OS 135 Error writeText(raw_fd_ostream &OS); 136 137 /// Write temporal profile trace data to the header in text format to \c OS 138 void writeTextTemporalProfTraceData(raw_fd_ostream &OS, 139 InstrProfSymtab &Symtab); 140 141 Error validateRecord(const InstrProfRecord &Func); 142 143 /// Write \c Record in text format to \c OS 144 static void writeRecordInText(StringRef Name, uint64_t Hash, 145 const InstrProfRecord &Counters, 146 InstrProfSymtab &Symtab, raw_fd_ostream &OS); 147 148 /// Write the profile, returning the raw data. For testing. 149 std::unique_ptr<MemoryBuffer> writeBuffer(); 150 151 /// Update the attributes of the current profile from the attributes 152 /// specified. An error is returned if IR and FE profiles are mixed. mergeProfileKind(const InstrProfKind Other)153 Error mergeProfileKind(const InstrProfKind Other) { 154 // If the kind is unset, this is the first profile we are merging so just 155 // set it to the given type. 156 if (ProfileKind == InstrProfKind::Unknown) { 157 ProfileKind = Other; 158 return Error::success(); 159 } 160 161 // Returns true if merging is should fail assuming A and B are incompatible. 162 auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) { 163 return (static_cast<bool>(ProfileKind & A) && 164 static_cast<bool>(Other & B)) || 165 (static_cast<bool>(ProfileKind & B) && 166 static_cast<bool>(Other & A)); 167 }; 168 169 // Check if the profiles are in-compatible. Clang frontend profiles can't be 170 // merged with other profile types. 171 if (static_cast<bool>( 172 (ProfileKind & InstrProfKind::FrontendInstrumentation) ^ 173 (Other & InstrProfKind::FrontendInstrumentation))) { 174 return make_error<InstrProfError>(instrprof_error::unsupported_version); 175 } 176 if (testIncompatible(InstrProfKind::FunctionEntryOnly, 177 InstrProfKind::FunctionEntryInstrumentation)) { 178 return make_error<InstrProfError>( 179 instrprof_error::unsupported_version, 180 "cannot merge FunctionEntryOnly profiles and BB profiles together"); 181 } 182 183 // Now we update the profile type with the bits that are set. 184 ProfileKind |= Other; 185 return Error::success(); 186 } 187 getProfileKind()188 InstrProfKind getProfileKind() const { return ProfileKind; } 189 hasSingleByteCoverage()190 bool hasSingleByteCoverage() const { 191 return static_cast<bool>(ProfileKind & InstrProfKind::SingleByteCoverage); 192 } 193 194 // Internal interfaces for testing purpose only. 195 void setValueProfDataEndianness(llvm::endianness Endianness); 196 void setOutputSparse(bool Sparse); setMemProfVersionRequested(memprof::IndexedVersion Version)197 void setMemProfVersionRequested(memprof::IndexedVersion Version) { 198 MemProfVersionRequested = Version; 199 } setMemProfFullSchema(bool Full)200 void setMemProfFullSchema(bool Full) { MemProfFullSchema = Full; } 201 // Compute the overlap b/w this object and Other. Program level result is 202 // stored in Overlap and function level result is stored in FuncLevelOverlap. 203 void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap, 204 OverlapStats &FuncLevelOverlap, 205 const OverlapFuncFilters &FuncFilter); 206 207 private: 208 void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I, 209 uint64_t Weight, function_ref<void(Error)> Warn); 210 bool shouldEncodeData(const ProfilingData &PD); 211 /// Add \p Trace using reservoir sampling. 212 void addTemporalProfileTrace(TemporalProfTraceTy Trace); 213 214 Error writeImpl(ProfOStream &OS); 215 216 // Writes known header fields and reserves space for fields whose value are 217 // known only after payloads are written. Returns the start byte offset for 218 // back patching. 219 uint64_t writeHeader(const IndexedInstrProf::Header &header, 220 const bool WritePrevVersion, ProfOStream &OS); 221 222 // Writes compressed vtable names to profiles. 223 Error writeVTableNames(ProfOStream &OS); 224 }; 225 226 } // end namespace llvm 227 228 #endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H 229