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