1 //=-- CoverageMappingReader.cpp - Code coverage mapping reader ----*- C++ -*-=//
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 coverage mapping data for
11 // instrumentation based coverage.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/ProfileData/CoverageMappingReader.h"
16 #include "llvm/ADT/DenseSet.h"
17 #include "llvm/Object/MachOUniversal.h"
18 #include "llvm/Object/ObjectFile.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Support/Endian.h"
21 #include "llvm/Support/LEB128.h"
22 #include "llvm/Support/MathExtras.h"
23 #include "llvm/Support/raw_ostream.h"
26 using namespace coverage;
27 using namespace object;
29 #define DEBUG_TYPE "coverage-mapping"
31 void CoverageMappingIterator::increment() {
32 // Check if all the records were read or if an error occurred while reading
34 if (Reader->readNextRecord(Record))
35 *this = CoverageMappingIterator();
38 std::error_code RawCoverageReader::readULEB128(uint64_t &Result) {
40 return coveragemap_error::truncated;
42 Result = decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N);
44 return coveragemap_error::malformed;
45 Data = Data.substr(N);
46 return std::error_code();
49 std::error_code RawCoverageReader::readIntMax(uint64_t &Result,
51 if (auto Err = readULEB128(Result))
53 if (Result >= MaxPlus1)
54 return coveragemap_error::malformed;
55 return std::error_code();
58 std::error_code RawCoverageReader::readSize(uint64_t &Result) {
59 if (auto Err = readULEB128(Result))
61 // Sanity check the number.
62 if (Result > Data.size())
63 return coveragemap_error::malformed;
64 return std::error_code();
67 std::error_code RawCoverageReader::readString(StringRef &Result) {
69 if (auto Err = readSize(Length))
71 Result = Data.substr(0, Length);
72 Data = Data.substr(Length);
73 return std::error_code();
76 std::error_code RawCoverageFilenamesReader::read() {
77 uint64_t NumFilenames;
78 if (auto Err = readSize(NumFilenames))
80 for (size_t I = 0; I < NumFilenames; ++I) {
82 if (auto Err = readString(Filename))
84 Filenames.push_back(Filename);
86 return std::error_code();
89 std::error_code RawCoverageMappingReader::decodeCounter(unsigned Value,
91 auto Tag = Value & Counter::EncodingTagMask;
94 C = Counter::getZero();
95 return std::error_code();
96 case Counter::CounterValueReference:
97 C = Counter::getCounter(Value >> Counter::EncodingTagBits);
98 return std::error_code();
102 Tag -= Counter::Expression;
104 case CounterExpression::Subtract:
105 case CounterExpression::Add: {
106 auto ID = Value >> Counter::EncodingTagBits;
107 if (ID >= Expressions.size())
108 return coveragemap_error::malformed;
109 Expressions[ID].Kind = CounterExpression::ExprKind(Tag);
110 C = Counter::getExpression(ID);
114 return coveragemap_error::malformed;
116 return std::error_code();
119 std::error_code RawCoverageMappingReader::readCounter(Counter &C) {
120 uint64_t EncodedCounter;
122 readIntMax(EncodedCounter, std::numeric_limits<unsigned>::max()))
124 if (auto Err = decodeCounter(EncodedCounter, C))
126 return std::error_code();
129 static const unsigned EncodingExpansionRegionBit = 1
130 << Counter::EncodingTagBits;
132 /// \brief Read the sub-array of regions for the given inferred file id.
133 /// \param NumFileIDs the number of file ids that are defined for this
135 std::error_code RawCoverageMappingReader::readMappingRegionsSubArray(
136 std::vector<CounterMappingRegion> &MappingRegions, unsigned InferredFileID,
139 if (auto Err = readSize(NumRegions))
141 unsigned LineStart = 0;
142 for (size_t I = 0; I < NumRegions; ++I) {
144 CounterMappingRegion::RegionKind Kind = CounterMappingRegion::CodeRegion;
146 // Read the combined counter + region kind.
147 uint64_t EncodedCounterAndRegion;
148 if (auto Err = readIntMax(EncodedCounterAndRegion,
149 std::numeric_limits<unsigned>::max()))
151 unsigned Tag = EncodedCounterAndRegion & Counter::EncodingTagMask;
152 uint64_t ExpandedFileID = 0;
153 if (Tag != Counter::Zero) {
154 if (auto Err = decodeCounter(EncodedCounterAndRegion, C))
157 // Is it an expansion region?
158 if (EncodedCounterAndRegion & EncodingExpansionRegionBit) {
159 Kind = CounterMappingRegion::ExpansionRegion;
160 ExpandedFileID = EncodedCounterAndRegion >>
161 Counter::EncodingCounterTagAndExpansionRegionTagBits;
162 if (ExpandedFileID >= NumFileIDs)
163 return coveragemap_error::malformed;
165 switch (EncodedCounterAndRegion >>
166 Counter::EncodingCounterTagAndExpansionRegionTagBits) {
167 case CounterMappingRegion::CodeRegion:
168 // Don't do anything when we have a code region with a zero counter.
170 case CounterMappingRegion::SkippedRegion:
171 Kind = CounterMappingRegion::SkippedRegion;
174 return coveragemap_error::malformed;
179 // Read the source range.
180 uint64_t LineStartDelta, ColumnStart, NumLines, ColumnEnd;
182 readIntMax(LineStartDelta, std::numeric_limits<unsigned>::max()))
184 if (auto Err = readULEB128(ColumnStart))
186 if (ColumnStart > std::numeric_limits<unsigned>::max())
187 return coveragemap_error::malformed;
188 if (auto Err = readIntMax(NumLines, std::numeric_limits<unsigned>::max()))
190 if (auto Err = readIntMax(ColumnEnd, std::numeric_limits<unsigned>::max()))
192 LineStart += LineStartDelta;
193 // Adjust the column locations for the empty regions that are supposed to
194 // cover whole lines. Those regions should be encoded with the
195 // column range (1 -> std::numeric_limits<unsigned>::max()), but because
196 // the encoded std::numeric_limits<unsigned>::max() is several bytes long,
197 // we set the column range to (0 -> 0) to ensure that the column start and
198 // column end take up one byte each.
199 // The std::numeric_limits<unsigned>::max() is used to represent a column
200 // position at the end of the line without knowing the length of that line.
201 if (ColumnStart == 0 && ColumnEnd == 0) {
203 ColumnEnd = std::numeric_limits<unsigned>::max();
207 dbgs() << "Counter in file " << InferredFileID << " " << LineStart << ":"
208 << ColumnStart << " -> " << (LineStart + NumLines) << ":"
209 << ColumnEnd << ", ";
210 if (Kind == CounterMappingRegion::ExpansionRegion)
211 dbgs() << "Expands to file " << ExpandedFileID;
213 CounterMappingContext(Expressions).dump(C, dbgs());
217 MappingRegions.push_back(CounterMappingRegion(
218 C, InferredFileID, ExpandedFileID, LineStart, ColumnStart,
219 LineStart + NumLines, ColumnEnd, Kind));
221 return std::error_code();
224 std::error_code RawCoverageMappingReader::read() {
226 // Read the virtual file mapping.
227 llvm::SmallVector<unsigned, 8> VirtualFileMapping;
228 uint64_t NumFileMappings;
229 if (auto Err = readSize(NumFileMappings))
231 for (size_t I = 0; I < NumFileMappings; ++I) {
232 uint64_t FilenameIndex;
233 if (auto Err = readIntMax(FilenameIndex, TranslationUnitFilenames.size()))
235 VirtualFileMapping.push_back(FilenameIndex);
238 // Construct the files using unique filenames and virtual file mapping.
239 for (auto I : VirtualFileMapping) {
240 Filenames.push_back(TranslationUnitFilenames[I]);
243 // Read the expressions.
244 uint64_t NumExpressions;
245 if (auto Err = readSize(NumExpressions))
247 // Create an array of dummy expressions that get the proper counters
248 // when the expressions are read, and the proper kinds when the counters
252 CounterExpression(CounterExpression::Subtract, Counter(), Counter()));
253 for (size_t I = 0; I < NumExpressions; ++I) {
254 if (auto Err = readCounter(Expressions[I].LHS))
256 if (auto Err = readCounter(Expressions[I].RHS))
260 // Read the mapping regions sub-arrays.
261 for (unsigned InferredFileID = 0, S = VirtualFileMapping.size();
262 InferredFileID < S; ++InferredFileID) {
263 if (auto Err = readMappingRegionsSubArray(MappingRegions, InferredFileID,
264 VirtualFileMapping.size()))
268 // Set the counters for the expansion regions.
269 // i.e. Counter of expansion region = counter of the first region
270 // from the expanded file.
271 // Perform multiple passes to correctly propagate the counters through
272 // all the nested expansion regions.
273 SmallVector<CounterMappingRegion *, 8> FileIDExpansionRegionMapping;
274 FileIDExpansionRegionMapping.resize(VirtualFileMapping.size(), nullptr);
275 for (unsigned Pass = 1, S = VirtualFileMapping.size(); Pass < S; ++Pass) {
276 for (auto &R : MappingRegions) {
277 if (R.Kind != CounterMappingRegion::ExpansionRegion)
279 assert(!FileIDExpansionRegionMapping[R.ExpandedFileID]);
280 FileIDExpansionRegionMapping[R.ExpandedFileID] = &R;
282 for (auto &R : MappingRegions) {
283 if (FileIDExpansionRegionMapping[R.FileID]) {
284 FileIDExpansionRegionMapping[R.FileID]->Count = R.Count;
285 FileIDExpansionRegionMapping[R.FileID] = nullptr;
290 return std::error_code();
295 /// \brief A helper structure to access the data from a section
296 /// in an object file.
301 std::error_code load(SectionRef &Section) {
302 if (auto Err = Section.getContents(Data))
304 Address = Section.getAddress();
305 return std::error_code();
308 std::error_code get(uint64_t Pointer, size_t Size, StringRef &Result) {
309 if (Pointer < Address)
310 return coveragemap_error::malformed;
311 auto Offset = Pointer - Address;
312 if (Offset + Size > Data.size())
313 return coveragemap_error::malformed;
314 Result = Data.substr(Pointer - Address, Size);
315 return std::error_code();
320 template <typename T, support::endianness Endian>
321 std::error_code readCoverageMappingData(
322 SectionData &ProfileNames, StringRef Data,
323 std::vector<BinaryCoverageReader::ProfileMappingRecord> &Records,
324 std::vector<StringRef> &Filenames) {
325 using namespace support;
326 llvm::DenseSet<T> UniqueFunctionMappingData;
328 // Read the records in the coverage data section.
329 for (const char *Buf = Data.data(), *End = Buf + Data.size(); Buf < End;) {
330 if (Buf + 4 * sizeof(uint32_t) > End)
331 return coveragemap_error::malformed;
332 uint32_t NRecords = endian::readNext<uint32_t, Endian, unaligned>(Buf);
333 uint32_t FilenamesSize = endian::readNext<uint32_t, Endian, unaligned>(Buf);
334 uint32_t CoverageSize = endian::readNext<uint32_t, Endian, unaligned>(Buf);
335 uint32_t Version = endian::readNext<uint32_t, Endian, unaligned>(Buf);
338 case CoverageMappingVersion1:
341 return coveragemap_error::unsupported_version;
344 // Skip past the function records, saving the start and end for later.
345 const char *FunBuf = Buf;
346 Buf += NRecords * (sizeof(T) + 2 * sizeof(uint32_t) + sizeof(uint64_t));
347 const char *FunEnd = Buf;
349 // Get the filenames.
350 if (Buf + FilenamesSize > End)
351 return coveragemap_error::malformed;
352 size_t FilenamesBegin = Filenames.size();
353 RawCoverageFilenamesReader Reader(StringRef(Buf, FilenamesSize), Filenames);
354 if (auto Err = Reader.read())
356 Buf += FilenamesSize;
358 // We'll read the coverage mapping records in the loop below.
359 const char *CovBuf = Buf;
361 const char *CovEnd = Buf;
364 return coveragemap_error::malformed;
365 // Each coverage map has an alignment of 8, so we need to adjust alignment
366 // before reading the next map.
367 Buf += alignmentAdjustment(Buf, 8);
369 while (FunBuf < FunEnd) {
370 // Read the function information
371 T NamePtr = endian::readNext<T, Endian, unaligned>(FunBuf);
372 uint32_t NameSize = endian::readNext<uint32_t, Endian, unaligned>(FunBuf);
373 uint32_t DataSize = endian::readNext<uint32_t, Endian, unaligned>(FunBuf);
374 uint64_t FuncHash = endian::readNext<uint64_t, Endian, unaligned>(FunBuf);
376 // Now use that to read the coverage data.
377 if (CovBuf + DataSize > CovEnd)
378 return coveragemap_error::malformed;
379 auto Mapping = StringRef(CovBuf, DataSize);
382 // Ignore this record if we already have a record that points to the same
383 // function name. This is useful to ignore the redundant records for the
384 // functions with ODR linkage.
385 if (!UniqueFunctionMappingData.insert(NamePtr).second)
388 // Finally, grab the name and create a record.
390 if (std::error_code EC = ProfileNames.get(NamePtr, NameSize, FuncName))
392 Records.push_back(BinaryCoverageReader::ProfileMappingRecord(
393 CoverageMappingVersion(Version), FuncName, FuncHash, Mapping,
394 FilenamesBegin, Filenames.size() - FilenamesBegin));
398 return std::error_code();
401 static const char *TestingFormatMagic = "llvmcovmtestdata";
403 static std::error_code loadTestingFormat(StringRef Data,
404 SectionData &ProfileNames,
405 StringRef &CoverageMapping,
406 uint8_t &BytesInAddress,
407 support::endianness &Endian) {
409 Endian = support::endianness::little;
411 Data = Data.substr(StringRef(TestingFormatMagic).size());
413 return coveragemap_error::truncated;
415 auto ProfileNamesSize =
416 decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N);
418 return coveragemap_error::malformed;
419 Data = Data.substr(N);
421 return coveragemap_error::truncated;
423 ProfileNames.Address =
424 decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N);
426 return coveragemap_error::malformed;
427 Data = Data.substr(N);
428 if (Data.size() < ProfileNamesSize)
429 return coveragemap_error::malformed;
430 ProfileNames.Data = Data.substr(0, ProfileNamesSize);
431 CoverageMapping = Data.substr(ProfileNamesSize);
432 return std::error_code();
435 static ErrorOr<SectionRef> lookupSection(ObjectFile &OF, StringRef Name) {
437 for (const auto &Section : OF.sections()) {
438 if (auto EC = Section.getName(FoundName))
440 if (FoundName == Name)
443 return coveragemap_error::no_data_found;
446 static std::error_code loadBinaryFormat(MemoryBufferRef ObjectBuffer,
447 SectionData &ProfileNames,
448 StringRef &CoverageMapping,
449 uint8_t &BytesInAddress,
450 support::endianness &Endian,
452 auto BinOrErr = object::createBinary(ObjectBuffer);
453 if (std::error_code EC = BinOrErr.getError())
455 auto Bin = std::move(BinOrErr.get());
456 std::unique_ptr<ObjectFile> OF;
457 if (auto *Universal = dyn_cast<object::MachOUniversalBinary>(Bin.get())) {
458 // If we have a universal binary, try to look up the object for the
459 // appropriate architecture.
460 auto ObjectFileOrErr = Universal->getObjectForArch(Arch);
461 if (std::error_code EC = ObjectFileOrErr.getError())
463 OF = std::move(ObjectFileOrErr.get());
464 } else if (isa<object::ObjectFile>(Bin.get())) {
465 // For any other object file, upcast and take ownership.
466 OF.reset(cast<object::ObjectFile>(Bin.release()));
467 // If we've asked for a particular arch, make sure they match.
468 if (!Arch.empty() && OF->getArch() != Triple(Arch).getArch())
469 return object_error::arch_not_found;
471 // We can only handle object files.
472 return coveragemap_error::malformed;
474 // The coverage uses native pointer sizes for the object it's written in.
475 BytesInAddress = OF->getBytesInAddress();
476 Endian = OF->isLittleEndian() ? support::endianness::little
477 : support::endianness::big;
479 // Look for the sections that we are interested in.
480 auto NamesSection = lookupSection(*OF, "__llvm_prf_names");
481 if (auto EC = NamesSection.getError())
483 auto CoverageSection = lookupSection(*OF, "__llvm_covmap");
484 if (auto EC = CoverageSection.getError())
487 // Get the contents of the given sections.
488 if (std::error_code EC = CoverageSection->getContents(CoverageMapping))
490 if (std::error_code EC = ProfileNames.load(*NamesSection))
493 return std::error_code();
496 ErrorOr<std::unique_ptr<BinaryCoverageReader>>
497 BinaryCoverageReader::create(std::unique_ptr<MemoryBuffer> &ObjectBuffer,
499 std::unique_ptr<BinaryCoverageReader> Reader(new BinaryCoverageReader());
503 uint8_t BytesInAddress;
504 support::endianness Endian;
506 if (ObjectBuffer->getBuffer().startswith(TestingFormatMagic))
507 // This is a special format used for testing.
508 EC = loadTestingFormat(ObjectBuffer->getBuffer(), Profile, Coverage,
509 BytesInAddress, Endian);
511 EC = loadBinaryFormat(ObjectBuffer->getMemBufferRef(), Profile, Coverage,
512 BytesInAddress, Endian, Arch);
516 if (BytesInAddress == 4 && Endian == support::endianness::little)
517 EC = readCoverageMappingData<uint32_t, support::endianness::little>(
518 Profile, Coverage, Reader->MappingRecords, Reader->Filenames);
519 else if (BytesInAddress == 4 && Endian == support::endianness::big)
520 EC = readCoverageMappingData<uint32_t, support::endianness::big>(
521 Profile, Coverage, Reader->MappingRecords, Reader->Filenames);
522 else if (BytesInAddress == 8 && Endian == support::endianness::little)
523 EC = readCoverageMappingData<uint64_t, support::endianness::little>(
524 Profile, Coverage, Reader->MappingRecords, Reader->Filenames);
525 else if (BytesInAddress == 8 && Endian == support::endianness::big)
526 EC = readCoverageMappingData<uint64_t, support::endianness::big>(
527 Profile, Coverage, Reader->MappingRecords, Reader->Filenames);
529 return coveragemap_error::malformed;
532 return std::move(Reader);
536 BinaryCoverageReader::readNextRecord(CoverageMappingRecord &Record) {
537 if (CurrentRecord >= MappingRecords.size())
538 return coveragemap_error::eof;
540 FunctionsFilenames.clear();
542 MappingRegions.clear();
543 auto &R = MappingRecords[CurrentRecord];
544 RawCoverageMappingReader Reader(
546 makeArrayRef(Filenames).slice(R.FilenamesBegin, R.FilenamesSize),
547 FunctionsFilenames, Expressions, MappingRegions);
548 if (auto Err = Reader.read())
551 Record.FunctionName = R.FunctionName;
552 Record.FunctionHash = R.FunctionHash;
553 Record.Filenames = FunctionsFilenames;
554 Record.Expressions = Expressions;
555 Record.MappingRegions = MappingRegions;
558 return std::error_code();