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/Endian.h" 25 #include "llvm/Support/Error.h" 26 #include <cstdint> 27 #include <memory> 28 #include <random> 29 30 namespace llvm { 31 32 /// Writer for instrumentation based profile data. 33 class InstrProfRecordWriterTrait; 34 class ProfOStream; 35 class MemoryBuffer; 36 class raw_fd_ostream; 37 38 class InstrProfWriter { 39 public: 40 using ProfilingData = SmallDenseMap<uint64_t, InstrProfRecord>; 41 42 private: 43 bool Sparse; 44 StringMap<ProfilingData> FunctionData; 45 /// The maximum length of a single temporal profile trace. 46 uint64_t MaxTemporalProfTraceLength; 47 /// The maximum number of stored temporal profile traces. 48 uint64_t TemporalProfTraceReservoirSize; 49 /// The total number of temporal profile traces seen. 50 uint64_t TemporalProfTraceStreamSize = 0; 51 /// The list of temporal profile traces. 52 SmallVector<TemporalProfTraceTy> TemporalProfTraces; 53 std::mt19937 RNG; 54 55 // A map to hold memprof data per function. The lower 64 bits obtained from 56 // the md5 hash of the function name is used to index into the map. 57 llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord> 58 MemProfRecordData; 59 // A map to hold frame id to frame mappings. The mappings are used to 60 // convert IndexedMemProfRecord to MemProfRecords with frame information 61 // inline. 62 llvm::MapVector<memprof::FrameId, memprof::Frame> MemProfFrameData; 63 64 // List of binary ids. 65 std::vector<llvm::object::BuildID> BinaryIds; 66 67 // An enum describing the attributes of the profile. 68 InstrProfKind ProfileKind = InstrProfKind::Unknown; 69 // Use raw pointer here for the incomplete type object. 70 InstrProfRecordWriterTrait *InfoObj; 71 72 public: 73 InstrProfWriter(bool Sparse = false, 74 uint64_t TemporalProfTraceReservoirSize = 0, 75 uint64_t MaxTemporalProfTraceLength = 0); 76 ~InstrProfWriter(); 77 78 StringMap<ProfilingData> &getProfileData() { return FunctionData; } 79 80 /// Add function counts for the given function. If there are already counts 81 /// for this function and the hash and number of counts match, each counter is 82 /// summed. Optionally scale counts by \p Weight. 83 void addRecord(NamedInstrProfRecord &&I, uint64_t Weight, 84 function_ref<void(Error)> Warn); 85 void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) { 86 addRecord(std::move(I), 1, Warn); 87 } 88 89 /// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the 90 /// total number of temporal profiling traces the source has seen. 91 void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces, 92 uint64_t SrcStreamSize); 93 94 /// Add a memprof record for a function identified by its \p Id. 95 void addMemProfRecord(const GlobalValue::GUID Id, 96 const memprof::IndexedMemProfRecord &Record); 97 98 /// Add a memprof frame identified by the hash of the contents of the frame in 99 /// \p FrameId. 100 bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F, 101 function_ref<void(Error)> Warn); 102 103 // Add a binary id to the binary ids list. 104 void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs); 105 106 /// Merge existing function counts from the given writer. 107 void mergeRecordsFromWriter(InstrProfWriter &&IPW, 108 function_ref<void(Error)> Warn); 109 110 /// Write the profile to \c OS 111 Error write(raw_fd_ostream &OS); 112 113 /// Write the profile to a string output stream \c OS 114 Error write(raw_string_ostream &OS); 115 116 /// Write the profile in text format to \c OS 117 Error writeText(raw_fd_ostream &OS); 118 119 /// Write temporal profile trace data to the header in text format to \c OS 120 void writeTextTemporalProfTraceData(raw_fd_ostream &OS, 121 InstrProfSymtab &Symtab); 122 123 Error validateRecord(const InstrProfRecord &Func); 124 125 /// Write \c Record in text format to \c OS 126 static void writeRecordInText(StringRef Name, uint64_t Hash, 127 const InstrProfRecord &Counters, 128 InstrProfSymtab &Symtab, raw_fd_ostream &OS); 129 130 /// Write the profile, returning the raw data. For testing. 131 std::unique_ptr<MemoryBuffer> writeBuffer(); 132 133 /// Update the attributes of the current profile from the attributes 134 /// specified. An error is returned if IR and FE profiles are mixed. 135 Error mergeProfileKind(const InstrProfKind Other) { 136 // If the kind is unset, this is the first profile we are merging so just 137 // set it to the given type. 138 if (ProfileKind == InstrProfKind::Unknown) { 139 ProfileKind = Other; 140 return Error::success(); 141 } 142 143 // Returns true if merging is should fail assuming A and B are incompatible. 144 auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) { 145 return (static_cast<bool>(ProfileKind & A) && 146 static_cast<bool>(Other & B)) || 147 (static_cast<bool>(ProfileKind & B) && 148 static_cast<bool>(Other & A)); 149 }; 150 151 // Check if the profiles are in-compatible. Clang frontend profiles can't be 152 // merged with other profile types. 153 if (static_cast<bool>( 154 (ProfileKind & InstrProfKind::FrontendInstrumentation) ^ 155 (Other & InstrProfKind::FrontendInstrumentation))) { 156 return make_error<InstrProfError>(instrprof_error::unsupported_version); 157 } 158 if (testIncompatible(InstrProfKind::FunctionEntryOnly, 159 InstrProfKind::FunctionEntryInstrumentation)) { 160 return make_error<InstrProfError>( 161 instrprof_error::unsupported_version, 162 "cannot merge FunctionEntryOnly profiles and BB profiles together"); 163 } 164 165 // Now we update the profile type with the bits that are set. 166 ProfileKind |= Other; 167 return Error::success(); 168 } 169 170 InstrProfKind getProfileKind() const { return ProfileKind; } 171 172 // Internal interface for testing purpose only. 173 void setValueProfDataEndianness(support::endianness Endianness); 174 void setOutputSparse(bool Sparse); 175 // Compute the overlap b/w this object and Other. Program level result is 176 // stored in Overlap and function level result is stored in FuncLevelOverlap. 177 void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap, 178 OverlapStats &FuncLevelOverlap, 179 const OverlapFuncFilters &FuncFilter); 180 181 private: 182 void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I, 183 uint64_t Weight, function_ref<void(Error)> Warn); 184 bool shouldEncodeData(const ProfilingData &PD); 185 /// Add \p Trace using reservoir sampling. 186 void addTemporalProfileTrace(TemporalProfTraceTy Trace); 187 188 Error writeImpl(ProfOStream &OS); 189 }; 190 191 } // end namespace llvm 192 193 #endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H 194