1 //=-- InstrProfReader.cpp - Instrumented profiling reader -------------------=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for reading profiling data for clang's
11 // instrumentation based PGO and coverage.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/ProfileData/InstrProfReader.h"
16 #include "InstrProfIndexed.h"
17 #include "llvm/ProfileData/InstrProf.h"
22 static ErrorOr<std::unique_ptr<MemoryBuffer>>
23 setupMemoryBuffer(std::string Path) {
24 ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
25 MemoryBuffer::getFileOrSTDIN(Path);
26 if (std::error_code EC = BufferOrErr.getError())
28 auto Buffer = std::move(BufferOrErr.get());
30 // Sanity check the file.
31 if (Buffer->getBufferSize() > std::numeric_limits<unsigned>::max())
32 return instrprof_error::too_large;
33 return std::move(Buffer);
36 static std::error_code initializeReader(InstrProfReader &Reader) {
37 return Reader.readHeader();
40 ErrorOr<std::unique_ptr<InstrProfReader>>
41 InstrProfReader::create(std::string Path) {
42 // Set up the buffer to read.
43 auto BufferOrError = setupMemoryBuffer(Path);
44 if (std::error_code EC = BufferOrError.getError())
47 auto Buffer = std::move(BufferOrError.get());
48 std::unique_ptr<InstrProfReader> Result;
51 if (IndexedInstrProfReader::hasFormat(*Buffer))
52 Result.reset(new IndexedInstrProfReader(std::move(Buffer)));
53 else if (RawInstrProfReader64::hasFormat(*Buffer))
54 Result.reset(new RawInstrProfReader64(std::move(Buffer)));
55 else if (RawInstrProfReader32::hasFormat(*Buffer))
56 Result.reset(new RawInstrProfReader32(std::move(Buffer)));
58 Result.reset(new TextInstrProfReader(std::move(Buffer)));
60 // Initialize the reader and return the result.
61 if (std::error_code EC = initializeReader(*Result))
64 return std::move(Result);
67 std::error_code IndexedInstrProfReader::create(
68 std::string Path, std::unique_ptr<IndexedInstrProfReader> &Result) {
69 // Set up the buffer to read.
70 auto BufferOrError = setupMemoryBuffer(Path);
71 if (std::error_code EC = BufferOrError.getError())
74 auto Buffer = std::move(BufferOrError.get());
76 if (!IndexedInstrProfReader::hasFormat(*Buffer))
77 return instrprof_error::bad_magic;
78 Result.reset(new IndexedInstrProfReader(std::move(Buffer)));
80 // Initialize the reader and return the result.
81 return initializeReader(*Result);
84 void InstrProfIterator::Increment() {
85 if (Reader->readNextRecord(Record))
86 *this = InstrProfIterator();
89 std::error_code TextInstrProfReader::readNextRecord(InstrProfRecord &Record) {
90 // Skip empty lines and comments.
91 while (!Line.is_at_end() && (Line->empty() || Line->startswith("#")))
93 // If we hit EOF while looking for a name, we're done.
95 return error(instrprof_error::eof);
97 // Read the function name.
98 Record.Name = *Line++;
100 // Read the function hash.
101 if (Line.is_at_end())
102 return error(instrprof_error::truncated);
103 if ((Line++)->getAsInteger(10, Record.Hash))
104 return error(instrprof_error::malformed);
106 // Read the number of counters.
107 uint64_t NumCounters;
108 if (Line.is_at_end())
109 return error(instrprof_error::truncated);
110 if ((Line++)->getAsInteger(10, NumCounters))
111 return error(instrprof_error::malformed);
112 if (NumCounters == 0)
113 return error(instrprof_error::malformed);
115 // Read each counter and fill our internal storage with the values.
117 Counts.reserve(NumCounters);
118 for (uint64_t I = 0; I < NumCounters; ++I) {
119 if (Line.is_at_end())
120 return error(instrprof_error::truncated);
122 if ((Line++)->getAsInteger(10, Count))
123 return error(instrprof_error::malformed);
124 Counts.push_back(Count);
126 // Give the record a reference to our internal counter storage.
127 Record.Counts = Counts;
132 template <class IntPtrT>
133 static uint64_t getRawMagic();
136 uint64_t getRawMagic<uint64_t>() {
138 uint64_t(255) << 56 |
139 uint64_t('l') << 48 |
140 uint64_t('p') << 40 |
141 uint64_t('r') << 32 |
142 uint64_t('o') << 24 |
143 uint64_t('f') << 16 |
149 uint64_t getRawMagic<uint32_t>() {
151 uint64_t(255) << 56 |
152 uint64_t('l') << 48 |
153 uint64_t('p') << 40 |
154 uint64_t('r') << 32 |
155 uint64_t('o') << 24 |
156 uint64_t('f') << 16 |
161 template <class IntPtrT>
162 bool RawInstrProfReader<IntPtrT>::hasFormat(const MemoryBuffer &DataBuffer) {
163 if (DataBuffer.getBufferSize() < sizeof(uint64_t))
166 *reinterpret_cast<const uint64_t *>(DataBuffer.getBufferStart());
167 return getRawMagic<IntPtrT>() == Magic ||
168 sys::getSwappedBytes(getRawMagic<IntPtrT>()) == Magic;
171 template <class IntPtrT>
172 std::error_code RawInstrProfReader<IntPtrT>::readHeader() {
173 if (!hasFormat(*DataBuffer))
174 return error(instrprof_error::bad_magic);
175 if (DataBuffer->getBufferSize() < sizeof(RawHeader))
176 return error(instrprof_error::bad_header);
178 reinterpret_cast<const RawHeader *>(DataBuffer->getBufferStart());
179 ShouldSwapBytes = Header->Magic != getRawMagic<IntPtrT>();
180 return readHeader(*Header);
183 template <class IntPtrT>
185 RawInstrProfReader<IntPtrT>::readNextHeader(const char *CurrentPos) {
186 const char *End = DataBuffer->getBufferEnd();
187 // Skip zero padding between profiles.
188 while (CurrentPos != End && *CurrentPos == 0)
190 // If there's nothing left, we're done.
191 if (CurrentPos == End)
192 return instrprof_error::eof;
193 // If there isn't enough space for another header, this is probably just
194 // garbage at the end of the file.
195 if (CurrentPos + sizeof(RawHeader) > End)
196 return instrprof_error::malformed;
197 // The writer ensures each profile is padded to start at an aligned address.
198 if (reinterpret_cast<size_t>(CurrentPos) % alignOf<uint64_t>())
199 return instrprof_error::malformed;
200 // The magic should have the same byte order as in the previous header.
201 uint64_t Magic = *reinterpret_cast<const uint64_t *>(CurrentPos);
202 if (Magic != swap(getRawMagic<IntPtrT>()))
203 return instrprof_error::bad_magic;
205 // There's another profile to read, so we need to process the header.
206 auto *Header = reinterpret_cast<const RawHeader *>(CurrentPos);
207 return readHeader(*Header);
210 static uint64_t getRawVersion() {
214 template <class IntPtrT>
216 RawInstrProfReader<IntPtrT>::readHeader(const RawHeader &Header) {
217 if (swap(Header.Version) != getRawVersion())
218 return error(instrprof_error::unsupported_version);
220 CountersDelta = swap(Header.CountersDelta);
221 NamesDelta = swap(Header.NamesDelta);
222 auto DataSize = swap(Header.DataSize);
223 auto CountersSize = swap(Header.CountersSize);
224 auto NamesSize = swap(Header.NamesSize);
226 ptrdiff_t DataOffset = sizeof(RawHeader);
227 ptrdiff_t CountersOffset = DataOffset + sizeof(ProfileData) * DataSize;
228 ptrdiff_t NamesOffset = CountersOffset + sizeof(uint64_t) * CountersSize;
229 size_t ProfileSize = NamesOffset + sizeof(char) * NamesSize;
231 auto *Start = reinterpret_cast<const char *>(&Header);
232 if (Start + ProfileSize > DataBuffer->getBufferEnd())
233 return error(instrprof_error::bad_header);
235 Data = reinterpret_cast<const ProfileData *>(Start + DataOffset);
236 DataEnd = Data + DataSize;
237 CountersStart = reinterpret_cast<const uint64_t *>(Start + CountersOffset);
238 NamesStart = Start + NamesOffset;
239 ProfileEnd = Start + ProfileSize;
244 template <class IntPtrT>
246 RawInstrProfReader<IntPtrT>::readNextRecord(InstrProfRecord &Record) {
248 if (std::error_code EC = readNextHeader(ProfileEnd))
252 StringRef RawName(getName(Data->NamePtr), swap(Data->NameSize));
253 uint32_t NumCounters = swap(Data->NumCounters);
254 if (NumCounters == 0)
255 return error(instrprof_error::malformed);
256 auto RawCounts = makeArrayRef(getCounter(Data->CounterPtr), NumCounters);
259 auto *NamesStartAsCounter = reinterpret_cast<const uint64_t *>(NamesStart);
260 if (RawName.data() < NamesStart ||
261 RawName.data() + RawName.size() > DataBuffer->getBufferEnd() ||
262 RawCounts.data() < CountersStart ||
263 RawCounts.data() + RawCounts.size() > NamesStartAsCounter)
264 return error(instrprof_error::malformed);
266 // Store the data in Record, byte-swapping as necessary.
267 Record.Hash = swap(Data->FuncHash);
268 Record.Name = RawName;
269 if (ShouldSwapBytes) {
271 Counts.reserve(RawCounts.size());
272 for (uint64_t Count : RawCounts)
273 Counts.push_back(swap(Count));
274 Record.Counts = Counts;
276 Record.Counts = RawCounts;
284 template class RawInstrProfReader<uint32_t>;
285 template class RawInstrProfReader<uint64_t>;
288 InstrProfLookupTrait::hash_value_type
289 InstrProfLookupTrait::ComputeHash(StringRef K) {
290 return IndexedInstrProf::ComputeHash(HashType, K);
293 bool IndexedInstrProfReader::hasFormat(const MemoryBuffer &DataBuffer) {
294 if (DataBuffer.getBufferSize() < 8)
296 using namespace support;
298 endian::read<uint64_t, little, aligned>(DataBuffer.getBufferStart());
299 return Magic == IndexedInstrProf::Magic;
302 std::error_code IndexedInstrProfReader::readHeader() {
303 const unsigned char *Start =
304 (const unsigned char *)DataBuffer->getBufferStart();
305 const unsigned char *Cur = Start;
306 if ((const unsigned char *)DataBuffer->getBufferEnd() - Cur < 24)
307 return error(instrprof_error::truncated);
309 using namespace support;
311 // Check the magic number.
312 uint64_t Magic = endian::readNext<uint64_t, little, unaligned>(Cur);
313 if (Magic != IndexedInstrProf::Magic)
314 return error(instrprof_error::bad_magic);
317 FormatVersion = endian::readNext<uint64_t, little, unaligned>(Cur);
318 if (FormatVersion > IndexedInstrProf::Version)
319 return error(instrprof_error::unsupported_version);
321 // Read the maximal function count.
322 MaxFunctionCount = endian::readNext<uint64_t, little, unaligned>(Cur);
324 // Read the hash type and start offset.
325 IndexedInstrProf::HashT HashType = static_cast<IndexedInstrProf::HashT>(
326 endian::readNext<uint64_t, little, unaligned>(Cur));
327 if (HashType > IndexedInstrProf::HashT::Last)
328 return error(instrprof_error::unsupported_hash_type);
329 uint64_t HashOffset = endian::readNext<uint64_t, little, unaligned>(Cur);
331 // The rest of the file is an on disk hash table.
332 Index.reset(InstrProfReaderIndex::Create(Start + HashOffset, Cur, Start,
333 InstrProfLookupTrait(HashType)));
334 // Set up our iterator for readNextRecord.
335 RecordIterator = Index->data_begin();
340 std::error_code IndexedInstrProfReader::getFunctionCounts(
341 StringRef FuncName, uint64_t FuncHash, std::vector<uint64_t> &Counts) {
342 auto Iter = Index->find(FuncName);
343 if (Iter == Index->end())
344 return error(instrprof_error::unknown_function);
346 // Found it. Look for counters with the right hash.
347 ArrayRef<uint64_t> Data = (*Iter).Data;
349 for (uint64_t I = 0, E = Data.size(); I != E; I += NumCounts) {
350 // The function hash comes first.
351 uint64_t FoundHash = Data[I++];
352 // In v1, we have at least one count. Later, we have the number of counts.
354 return error(instrprof_error::malformed);
355 NumCounts = FormatVersion == 1 ? E - I : Data[I++];
356 // If we have more counts than data, this is bogus.
357 if (I + NumCounts > E)
358 return error(instrprof_error::malformed);
359 // Check for a match and fill the vector if there is one.
360 if (FoundHash == FuncHash) {
361 Counts = Data.slice(I, NumCounts);
365 return error(instrprof_error::hash_mismatch);
369 IndexedInstrProfReader::readNextRecord(InstrProfRecord &Record) {
370 // Are we out of records?
371 if (RecordIterator == Index->data_end())
372 return error(instrprof_error::eof);
374 // Record the current function name.
375 Record.Name = (*RecordIterator).Name;
377 ArrayRef<uint64_t> Data = (*RecordIterator).Data;
378 // Valid data starts with a hash and either a count or the number of counts.
379 if (CurrentOffset + 1 > Data.size())
380 return error(instrprof_error::malformed);
381 // First we have a function hash.
382 Record.Hash = Data[CurrentOffset++];
383 // In version 1 we knew the number of counters implicitly, but in newer
384 // versions we store the number of counters next.
386 FormatVersion == 1 ? Data.size() - CurrentOffset : Data[CurrentOffset++];
387 if (CurrentOffset + NumCounts > Data.size())
388 return error(instrprof_error::malformed);
389 // And finally the counts themselves.
390 Record.Counts = Data.slice(CurrentOffset, NumCounts);
392 // If we've exhausted this function's data, increment the record.
393 CurrentOffset += NumCounts;
394 if (CurrentOffset == Data.size()) {