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-rw-r--r--llvm/lib/ProfileData/CoverageMapping.cpp149
-rw-r--r--llvm/lib/ProfileData/CoverageMappingReader.cpp482
-rw-r--r--llvm/lib/ProfileData/CoverageMappingWriter.cpp197
3 files changed, 828 insertions, 0 deletions
diff --git a/llvm/lib/ProfileData/CoverageMapping.cpp b/llvm/lib/ProfileData/CoverageMapping.cpp
new file mode 100644
index 00000000000..30132a3f749
--- /dev/null
+++ b/llvm/lib/ProfileData/CoverageMapping.cpp
@@ -0,0 +1,149 @@
+//=-- CoverageMapping.cpp - Code coverage mapping support ---------*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for clang's and llvm's instrumentation based
+// code coverage.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ProfileData/CoverageMapping.h"
+
+using namespace llvm;
+using namespace coverage;
+
+CounterExpressionBuilder::CounterExpressionBuilder(unsigned NumCounterValues) {
+ Terms.resize(NumCounterValues);
+}
+
+Counter CounterExpressionBuilder::get(const CounterExpression &E) {
+ for (unsigned I = 0, S = Expressions.size(); I < S; ++I) {
+ if (Expressions[I] == E)
+ return Counter::getExpression(I);
+ }
+ Expressions.push_back(E);
+ return Counter::getExpression(Expressions.size() - 1);
+}
+
+void CounterExpressionBuilder::extractTerms(Counter C, int Sign) {
+ switch (C.getKind()) {
+ case Counter::Zero:
+ break;
+ case Counter::CounterValueReference:
+ Terms[C.getCounterID()] += Sign;
+ break;
+ case Counter::Expression:
+ const auto &E = Expressions[C.getExpressionID()];
+ extractTerms(E.LHS, Sign);
+ extractTerms(E.RHS, E.Kind == CounterExpression::Subtract ? -Sign : Sign);
+ break;
+ }
+}
+
+Counter CounterExpressionBuilder::simplify(Counter ExpressionTree) {
+ // Gather constant terms.
+ for (auto &I : Terms)
+ I = 0;
+ extractTerms(ExpressionTree);
+
+ Counter C;
+ // Create additions.
+ // Note: the additions are created first
+ // to avoid creation of a tree like ((0 - X) + Y) instead of (Y - X).
+ for (unsigned I = 0, S = Terms.size(); I < S; ++I) {
+ if (Terms[I] <= 0)
+ continue;
+ for (int J = 0; J < Terms[I]; ++J) {
+ if (C.isZero())
+ C = Counter::getCounter(I);
+ else
+ C = get(CounterExpression(CounterExpression::Add, C,
+ Counter::getCounter(I)));
+ }
+ }
+
+ // Create subtractions.
+ for (unsigned I = 0, S = Terms.size(); I < S; ++I) {
+ if (Terms[I] >= 0)
+ continue;
+ for (int J = 0; J < (-Terms[I]); ++J)
+ C = get(CounterExpression(CounterExpression::Subtract, C,
+ Counter::getCounter(I)));
+ }
+ return C;
+}
+
+Counter CounterExpressionBuilder::add(Counter LHS, Counter RHS) {
+ return simplify(get(CounterExpression(CounterExpression::Add, LHS, RHS)));
+}
+
+Counter CounterExpressionBuilder::subtract(Counter LHS, Counter RHS) {
+ return simplify(
+ get(CounterExpression(CounterExpression::Subtract, LHS, RHS)));
+}
+
+void CounterMappingContext::dump(const Counter &C,
+ llvm::raw_ostream &OS) const {
+ switch (C.getKind()) {
+ case Counter::Zero:
+ OS << '0';
+ return;
+ case Counter::CounterValueReference:
+ OS << '#' << C.getCounterID();
+ break;
+ case Counter::Expression: {
+ if (C.getExpressionID() >= Expressions.size())
+ return;
+ const auto &E = Expressions[C.getExpressionID()];
+ OS << '(';
+ dump(E.LHS);
+ OS << (E.Kind == CounterExpression::Subtract ? " - " : " + ");
+ dump(E.RHS);
+ OS << ')';
+ break;
+ }
+ }
+ if (CounterValues.empty())
+ return;
+ std::error_code Error;
+ auto Value = evaluate(C, Error);
+ if (Error)
+ return;
+ OS << '[' << Value << ']';
+}
+
+int64_t CounterMappingContext::evaluate(const Counter &C,
+ std::error_code *EC) const {
+ switch (C.getKind()) {
+ case Counter::Zero:
+ return 0;
+ case Counter::CounterValueReference:
+ if (C.getCounterID() >= CounterValues.size()) {
+ if (EC)
+ *EC = std::make_error_code(std::errc::argument_out_of_domain);
+ break;
+ }
+ return CounterValues[C.getCounterID()];
+ case Counter::Expression: {
+ if (C.getExpressionID() >= Expressions.size()) {
+ if (EC)
+ *EC = std::make_error_code(std::errc::argument_out_of_domain);
+ break;
+ }
+ const auto &E = Expressions[C.getExpressionID()];
+ auto LHS = evaluate(E.LHS, EC);
+ if (EC && *EC)
+ return 0;
+ auto RHS = evaluate(E.RHS, EC);
+ if (EC && *EC)
+ return 0;
+ return E.Kind == CounterExpression::Subtract ? LHS - RHS : LHS + RHS;
+ }
+ }
+ return 0;
+}
diff --git a/llvm/lib/ProfileData/CoverageMappingReader.cpp b/llvm/lib/ProfileData/CoverageMappingReader.cpp
new file mode 100644
index 00000000000..83c707fa43d
--- /dev/null
+++ b/llvm/lib/ProfileData/CoverageMappingReader.cpp
@@ -0,0 +1,482 @@
+//=-- CoverageMappingReader.cpp - Code coverage mapping reader ----*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for reading coverage mapping data for
+// instrumentation based coverage.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ProfileData/CoverageMappingReader.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/LEB128.h"
+
+using namespace llvm;
+using namespace coverage;
+using namespace object;
+
+void CoverageMappingIterator::increment() {
+ // Check if all the records were read or if an error occurred while reading
+ // the next record.
+ if (Reader->readNextRecord(Record))
+ *this = CoverageMappingIterator();
+}
+
+std::error_code RawCoverageReader::readULEB128(uint64_t &Result) {
+ if (Data.size() < 1)
+ return error(instrprof_error::truncated);
+ unsigned N = 0;
+ Result = decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N);
+ if (N > Data.size())
+ return error(instrprof_error::malformed);
+ Data = Data.substr(N);
+ return success();
+}
+
+std::error_code RawCoverageReader::readIntMax(uint64_t &Result,
+ uint64_t MaxPlus1) {
+ if (auto Err = readULEB128(Result))
+ return Err;
+ if (Result >= MaxPlus1)
+ return error(instrprof_error::malformed);
+ return success();
+}
+
+std::error_code RawCoverageReader::readSize(uint64_t &Result) {
+ if (auto Err = readULEB128(Result))
+ return Err;
+ // Sanity check the number.
+ if (Result > Data.size())
+ return error(instrprof_error::malformed);
+ return success();
+}
+
+std::error_code RawCoverageReader::readString(StringRef &Result) {
+ uint64_t Length;
+ if (auto Err = readSize(Length))
+ return Err;
+ Result = Data.substr(0, Length);
+ Data = Data.substr(Length);
+ return success();
+}
+
+std::error_code RawCoverageFilenamesReader::read() {
+ uint64_t NumFilenames;
+ if (auto Err = readSize(NumFilenames))
+ return Err;
+ for (size_t I = 0; I < NumFilenames; ++I) {
+ StringRef Filename;
+ if (auto Err = readString(Filename))
+ return Err;
+ Filenames.push_back(Filename);
+ }
+ return success();
+}
+
+std::error_code RawCoverageMappingReader::decodeCounter(unsigned Value,
+ Counter &C) {
+ auto Tag = Value & Counter::EncodingTagMask;
+ switch (Tag) {
+ case Counter::Zero:
+ C = Counter::getZero();
+ return success();
+ case Counter::CounterValueReference:
+ C = Counter::getCounter(Value >> Counter::EncodingTagBits);
+ return success();
+ default:
+ break;
+ }
+ Tag -= Counter::Expression;
+ switch (Tag) {
+ case CounterExpression::Subtract:
+ case CounterExpression::Add: {
+ auto ID = Value >> Counter::EncodingTagBits;
+ if (ID >= Expressions.size())
+ return error(instrprof_error::malformed);
+ Expressions[ID].Kind = CounterExpression::ExprKind(Tag);
+ C = Counter::getExpression(ID);
+ break;
+ }
+ default:
+ return error(instrprof_error::malformed);
+ }
+ return success();
+}
+
+std::error_code RawCoverageMappingReader::readCounter(Counter &C) {
+ uint64_t EncodedCounter;
+ if (auto Err =
+ readIntMax(EncodedCounter, std::numeric_limits<unsigned>::max()))
+ return Err;
+ if (auto Err = decodeCounter(EncodedCounter, C))
+ return Err;
+ return success();
+}
+
+static const unsigned EncodingExpansionRegionBit = 1
+ << Counter::EncodingTagBits;
+
+/// \brief Read the sub-array of regions for the given inferred file id.
+/// \param NumFileIDs: the number of file ids that are defined for this
+/// function.
+std::error_code RawCoverageMappingReader::readMappingRegionsSubArray(
+ std::vector<CounterMappingRegion> &MappingRegions, unsigned InferredFileID,
+ size_t NumFileIDs) {
+ uint64_t NumRegions;
+ if (auto Err = readSize(NumRegions))
+ return Err;
+ unsigned LineStart = 0;
+ for (size_t I = 0; I < NumRegions; ++I) {
+ Counter C;
+ CounterMappingRegion::RegionKind Kind = CounterMappingRegion::CodeRegion;
+
+ // Read the combined counter + region kind.
+ uint64_t EncodedCounterAndRegion;
+ if (auto Err = readIntMax(EncodedCounterAndRegion,
+ std::numeric_limits<unsigned>::max()))
+ return Err;
+ unsigned Tag = EncodedCounterAndRegion & Counter::EncodingTagMask;
+ uint64_t ExpandedFileID = 0;
+ if (Tag != Counter::Zero) {
+ if (auto Err = decodeCounter(EncodedCounterAndRegion, C))
+ return Err;
+ } else {
+ // Is it an expansion region?
+ if (EncodedCounterAndRegion & EncodingExpansionRegionBit) {
+ Kind = CounterMappingRegion::ExpansionRegion;
+ ExpandedFileID = EncodedCounterAndRegion >>
+ Counter::EncodingCounterTagAndExpansionRegionTagBits;
+ if (ExpandedFileID >= NumFileIDs)
+ return error(instrprof_error::malformed);
+ } else {
+ switch (EncodedCounterAndRegion >>
+ Counter::EncodingCounterTagAndExpansionRegionTagBits) {
+ case CounterMappingRegion::CodeRegion:
+ // Don't do anything when we have a code region with a zero counter.
+ break;
+ case CounterMappingRegion::EmptyRegion:
+ Kind = CounterMappingRegion::EmptyRegion;
+ break;
+ case CounterMappingRegion::SkippedRegion:
+ Kind = CounterMappingRegion::SkippedRegion;
+ break;
+ default:
+ return error(instrprof_error::malformed);
+ }
+ }
+ }
+
+ // Read the source range.
+ uint64_t LineStartDelta, ColumnStart, NumLines, ColumnEnd;
+ if (auto Err =
+ readIntMax(LineStartDelta, std::numeric_limits<unsigned>::max()))
+ return Err;
+ if (auto Err =
+ readIntMax(ColumnStart, std::numeric_limits<unsigned>::max()))
+ return Err;
+ if (auto Err = readIntMax(NumLines, std::numeric_limits<unsigned>::max()))
+ return Err;
+ if (auto Err = readIntMax(ColumnEnd, std::numeric_limits<unsigned>::max()))
+ return Err;
+ LineStart += LineStartDelta;
+ // Adjust the column locations for the empty regions that are supposed to
+ // cover whole lines. Those regions should be encoded with the
+ // column range (1 -> std::numeric_limits<unsigned>::max()), but because
+ // the encoded std::numeric_limits<unsigned>::max() is several bytes long,
+ // we set the column range to (0 -> 0) to ensure that the column start and
+ // column end take up one byte each.
+ // The std::numeric_limits<unsigned>::max() is used to represent a column
+ // position at the end of the line without knowing the length of that line.
+ if (ColumnStart == 0 && ColumnEnd == 0) {
+ ColumnStart = 1;
+ ColumnEnd = std::numeric_limits<unsigned>::max();
+ }
+ MappingRegions.push_back(
+ CounterMappingRegion(C, InferredFileID, LineStart, ColumnStart,
+ LineStart + NumLines, ColumnEnd, Kind));
+ MappingRegions.back().ExpandedFileID = ExpandedFileID;
+ }
+ return success();
+}
+
+std::error_code RawCoverageMappingReader::read(CoverageMappingRecord &Record) {
+
+ // Read the virtual file mapping.
+ llvm::SmallVector<unsigned, 8> VirtualFileMapping;
+ uint64_t NumFileMappings;
+ if (auto Err = readSize(NumFileMappings))
+ return Err;
+ for (size_t I = 0; I < NumFileMappings; ++I) {
+ uint64_t FilenameIndex;
+ if (auto Err = readIntMax(FilenameIndex, TranslationUnitFilenames.size()))
+ return Err;
+ VirtualFileMapping.push_back(FilenameIndex);
+ }
+
+ // Construct the files using unique filenames and virtual file mapping.
+ for (auto I : VirtualFileMapping) {
+ Filenames.push_back(TranslationUnitFilenames[I]);
+ }
+
+ // Read the expressions.
+ uint64_t NumExpressions;
+ if (auto Err = readSize(NumExpressions))
+ return Err;
+ // Create an array of dummy expressions that get the proper counters
+ // when the expressions are read, and the proper kinds when the counters
+ // are decoded.
+ Expressions.resize(
+ NumExpressions,
+ CounterExpression(CounterExpression::Subtract, Counter(), Counter()));
+ for (size_t I = 0; I < NumExpressions; ++I) {
+ if (auto Err = readCounter(Expressions[I].LHS))
+ return Err;
+ if (auto Err = readCounter(Expressions[I].RHS))
+ return Err;
+ }
+
+ // Read the mapping regions sub-arrays.
+ for (unsigned InferredFileID = 0, S = VirtualFileMapping.size();
+ InferredFileID < S; ++InferredFileID) {
+ if (auto Err = readMappingRegionsSubArray(MappingRegions, InferredFileID,
+ VirtualFileMapping.size()))
+ return Err;
+ }
+
+ // Set the counters for the expansion regions.
+ // i.e. Counter of expansion region = counter of the first region
+ // from the expanded file.
+ // Perform multiple passes to correctly propagate the counters through
+ // all the nested expansion regions.
+ for (unsigned Pass = 1, S = VirtualFileMapping.size(); Pass < S; ++Pass) {
+ for (auto &I : MappingRegions) {
+ if (I.Kind == CounterMappingRegion::ExpansionRegion) {
+ for (const auto &J : MappingRegions) {
+ if (J.FileID == I.ExpandedFileID) {
+ I.Count = J.Count;
+ break;
+ }
+ }
+ }
+ }
+ }
+
+ Record.FunctionName = FunctionName;
+ Record.Filenames = Filenames;
+ Record.Expressions = Expressions;
+ Record.MappingRegions = MappingRegions;
+ return success();
+}
+
+ObjectFileCoverageMappingReader::ObjectFileCoverageMappingReader(
+ StringRef FileName)
+ : CurrentRecord(0) {
+ auto File = llvm::object::ObjectFile::createObjectFile(FileName);
+ if (!File)
+ error(File.getError());
+ else
+ Object.reset(File.get());
+}
+
+ObjectFileCoverageMappingReader::ObjectFileCoverageMappingReader(
+ std::unique_ptr<MemoryBuffer> &ObjectBuffer, sys::fs::file_magic Type)
+ : CurrentRecord(0) {
+ auto File = llvm::object::ObjectFile::createObjectFile(ObjectBuffer, Type);
+ if (!File)
+ error(File.getError());
+ else
+ Object.reset(File.get());
+}
+
+namespace {
+/// \brief The coverage mapping data for a single function.
+/// It points to the function's name.
+template <typename IntPtrT> struct CoverageMappingFunctionRecord {
+ IntPtrT FunctionNamePtr;
+ uint32_t FunctionNameSize;
+ uint32_t CoverageMappingSize;
+};
+
+/// \brief The coverage mapping data for a single translation unit.
+/// It points to the array of function coverage mapping records and the encoded
+/// filenames array.
+template <typename IntPtrT> struct CoverageMappingTURecord {
+ uint32_t FunctionRecordsSize;
+ uint32_t FilenamesSize;
+ uint32_t CoverageMappingsSize;
+ uint32_t Version;
+};
+
+/// \brief A helper structure to access the data from a section
+/// in an object file.
+struct SectionData {
+ StringRef Data;
+ uint64_t Address;
+
+ std::error_code load(SectionRef &Section) {
+ if (auto Err = Section.getContents(Data))
+ return Err;
+ return Section.getAddress(Address);
+ }
+
+ std::error_code get(uint64_t Pointer, size_t Size, StringRef &Result) {
+ if (Pointer < Address)
+ return instrprof_error::malformed;
+ auto Offset = Pointer - Address;
+ if (Offset + Size > Data.size())
+ return instrprof_error::malformed;
+ Result = Data.substr(Pointer - Address, Size);
+ return instrprof_error::success;
+ }
+};
+}
+
+template <typename T>
+std::error_code readCoverageMappingData(
+ SectionRef &ProfileNames, SectionRef &CoverageMapping,
+ std::vector<ObjectFileCoverageMappingReader::ProfileMappingRecord> &Records,
+ std::vector<StringRef> &Filenames) {
+ llvm::DenseSet<T> UniqueFunctionMappingData;
+
+ // Get the contents of the given sections.
+ StringRef Data;
+ if (auto Err = CoverageMapping.getContents(Data))
+ return Err;
+ SectionData ProfileNamesData;
+ if (auto Err = ProfileNamesData.load(ProfileNames))
+ return Err;
+
+ // Read the records in the coverage data section.
+ while (!Data.empty()) {
+ if (Data.size() < sizeof(CoverageMappingTURecord<T>))
+ return instrprof_error::malformed;
+ auto TU = reinterpret_cast<const CoverageMappingTURecord<T> *>(Data.data());
+ Data = Data.substr(sizeof(CoverageMappingTURecord<T>));
+ switch (TU->Version) {
+ case CoverageMappingVersion1:
+ break;
+ default:
+ return instrprof_error::unsupported_version;
+ }
+ auto Version = CoverageMappingVersion(TU->Version);
+
+ // Get the function records.
+ auto FunctionRecords =
+ reinterpret_cast<const CoverageMappingFunctionRecord<T> *>(Data.data());
+ if (Data.size() <
+ sizeof(CoverageMappingFunctionRecord<T>) * TU->FunctionRecordsSize)
+ return instrprof_error::malformed;
+ Data = Data.substr(sizeof(CoverageMappingFunctionRecord<T>) *
+ TU->FunctionRecordsSize);
+
+ // Get the filenames.
+ if (Data.size() < TU->FilenamesSize)
+ return instrprof_error::malformed;
+ auto RawFilenames = Data.substr(0, TU->FilenamesSize);
+ Data = Data.substr(TU->FilenamesSize);
+ size_t FilenamesBegin = Filenames.size();
+ RawCoverageFilenamesReader Reader(RawFilenames, Filenames);
+ if (auto Err = Reader.read())
+ return Err;
+
+ // Get the coverage mappings.
+ if (Data.size() < TU->CoverageMappingsSize)
+ return instrprof_error::malformed;
+ auto CoverageMappings = Data.substr(0, TU->CoverageMappingsSize);
+ Data = Data.substr(TU->CoverageMappingsSize);
+
+ for (unsigned I = 0; I < TU->FunctionRecordsSize; ++I) {
+ auto &MappingRecord = FunctionRecords[I];
+
+ // Get the coverage mapping.
+ if (CoverageMappings.size() < MappingRecord.CoverageMappingSize)
+ return instrprof_error::malformed;
+ auto Mapping =
+ CoverageMappings.substr(0, MappingRecord.CoverageMappingSize);
+ CoverageMappings =
+ CoverageMappings.substr(MappingRecord.CoverageMappingSize);
+
+ // Ignore this record if we already have a record that points to the same
+ // function name.
+ // This is useful to ignore the redundant records for the functions
+ // with ODR linkage.
+ if (UniqueFunctionMappingData.count(MappingRecord.FunctionNamePtr))
+ continue;
+ UniqueFunctionMappingData.insert(MappingRecord.FunctionNamePtr);
+ StringRef FunctionName;
+ if (auto Err = ProfileNamesData.get(MappingRecord.FunctionNamePtr,
+ MappingRecord.FunctionNameSize,
+ FunctionName))
+ return Err;
+ Records.push_back(ObjectFileCoverageMappingReader::ProfileMappingRecord(
+ Version, FunctionName, Mapping, FilenamesBegin,
+ Filenames.size() - FilenamesBegin));
+ }
+ }
+
+ return instrprof_error::success;
+}
+
+std::error_code ObjectFileCoverageMappingReader::readHeader() {
+ if (!Object)
+ return getError();
+ auto BytesInAddress = Object->getBytesInAddress();
+ if (BytesInAddress != 4 && BytesInAddress != 8)
+ return error(instrprof_error::malformed);
+
+ // Look for the sections that we are interested in.
+ int FoundSectionCount = 0;
+ SectionRef ProfileNames, CoverageMapping;
+ for (const auto &Section : Object->sections()) {
+ StringRef Name;
+ if (auto Err = Section.getName(Name))
+ return Err;
+ if (Name == "__llvm_prf_names") {
+ ProfileNames = Section;
+ } else if (Name == "__llvm_covmap") {
+ CoverageMapping = Section;
+ } else
+ continue;
+ ++FoundSectionCount;
+ }
+ if (FoundSectionCount != 2)
+ return error(instrprof_error::bad_header);
+
+ // Load the data from the found sections.
+ std::error_code Err;
+ if (BytesInAddress == 4)
+ Err = readCoverageMappingData<uint32_t>(ProfileNames, CoverageMapping,
+ MappingRecords, Filenames);
+ else
+ Err = readCoverageMappingData<uint64_t>(ProfileNames, CoverageMapping,
+ MappingRecords, Filenames);
+ if (Err)
+ return error(Err);
+
+ return success();
+}
+
+std::error_code
+ObjectFileCoverageMappingReader::readNextRecord(CoverageMappingRecord &Record) {
+ if (CurrentRecord >= MappingRecords.size())
+ return error(instrprof_error::eof);
+
+ FunctionsFilenames.clear();
+ Expressions.clear();
+ MappingRegions.clear();
+ auto &R = MappingRecords[CurrentRecord];
+ RawCoverageMappingReader Reader(
+ R.FunctionName, R.CoverageMapping,
+ makeArrayRef(Filenames.data() + R.FilenamesBegin, R.FilenamesSize),
+ FunctionsFilenames, Expressions, MappingRegions);
+ if (auto Err = Reader.read(Record))
+ return Err;
+ ++CurrentRecord;
+ return success();
+}
diff --git a/llvm/lib/ProfileData/CoverageMappingWriter.cpp b/llvm/lib/ProfileData/CoverageMappingWriter.cpp
new file mode 100644
index 00000000000..0e8c0445f90
--- /dev/null
+++ b/llvm/lib/ProfileData/CoverageMappingWriter.cpp
@@ -0,0 +1,197 @@
+//=-- CoverageMappingWriter.cpp - Code coverage mapping writer -------------=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing coverage mapping data for
+// instrumentation based coverage.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ProfileData/CoverageMappingWriter.h"
+#include "llvm/Support/LEB128.h"
+
+using namespace llvm;
+using namespace coverage;
+
+void CoverageFilenamesSectionWriter::write(raw_ostream &OS) {
+ encodeULEB128(Filenames.size(), OS);
+ for (const auto &Filename : Filenames) {
+ encodeULEB128(Filename.size(), OS);
+ OS << Filename;
+ }
+}
+
+namespace {
+/// \brief Gather only the expressions that are used by the mapping
+/// regions in this function.
+class CounterExpressionsMinimizer {
+ ArrayRef<CounterExpression> Expressions;
+ llvm::SmallVector<CounterExpression, 16> UsedExpressions;
+ std::vector<unsigned> AdjustedExpressionIDs;
+
+public:
+ void mark(Counter C) {
+ if (!C.isExpression())
+ return;
+ unsigned ID = C.getExpressionID();
+ AdjustedExpressionIDs[ID] = 1;
+ mark(Expressions[ID].LHS);
+ mark(Expressions[ID].RHS);
+ }
+
+ void gatherUsed(Counter C) {
+ if (!C.isExpression() || !AdjustedExpressionIDs[C.getExpressionID()])
+ return;
+ AdjustedExpressionIDs[C.getExpressionID()] = UsedExpressions.size();
+ const auto &E = Expressions[C.getExpressionID()];
+ UsedExpressions.push_back(E);
+ gatherUsed(E.LHS);
+ gatherUsed(E.RHS);
+ }
+
+ CounterExpressionsMinimizer(ArrayRef<CounterExpression> Expressions,
+ ArrayRef<CounterMappingRegion> MappingRegions)
+ : Expressions(Expressions) {
+ AdjustedExpressionIDs.resize(Expressions.size(), 0);
+ for (const auto &I : MappingRegions)
+ mark(I.Count);
+ for (const auto &I : MappingRegions)
+ gatherUsed(I.Count);
+ }
+
+ ArrayRef<CounterExpression> getExpressions() const { return UsedExpressions; }
+
+ /// \brief Adjust the given counter to correctly transition from the old
+ /// expression ids to the new expression ids.
+ Counter adjust(Counter C) const {
+ if (C.isExpression())
+ C = Counter::getExpression(AdjustedExpressionIDs[C.getExpressionID()]);
+ return C;
+ }
+};
+}
+
+/// \brief Return the number of regions that have the given FileID.
+static unsigned countFileIDs(ArrayRef<CounterMappingRegion> Regions,
+ unsigned FileID) {
+ unsigned Result = 0;
+ for (const auto &I : Regions) {
+ if (I.FileID == FileID)
+ ++Result;
+ if (I.FileID > FileID)
+ break;
+ }
+ return Result;
+}
+
+/// \brief Encode the counter.
+///
+/// The encoding uses the following format:
+/// Low 2 bits - Tag:
+/// Counter::Zero(0) - A Counter with kind Counter::Zero
+/// Counter::CounterValueReference(1) - A counter with kind
+/// Counter::CounterValueReference
+/// Counter::Expression(2) + CounterExpression::Subtract(0) -
+/// A counter with kind Counter::Expression and an expression
+/// with kind CounterExpression::Subtract
+/// Counter::Expression(2) + CounterExpression::Add(1) -
+/// A counter with kind Counter::Expression and an expression
+/// with kind CounterExpression::Add
+/// Remaining bits - Counter/Expression ID.
+unsigned encodeCounter(ArrayRef<CounterExpression> Expressions, Counter C) {
+ unsigned Tag = unsigned(C.getKind());
+ if (C.isExpression())
+ Tag += Expressions[C.getExpressionID()].Kind;
+ unsigned ID = C.getCounterID();
+ assert(ID <=
+ (std::numeric_limits<unsigned>::max() >> Counter::EncodingTagBits));
+ return Tag | (ID << Counter::EncodingTagBits);
+}
+
+static void writeCounter(ArrayRef<CounterExpression> Expressions, Counter C,
+ raw_ostream &OS) {
+ encodeULEB128(encodeCounter(Expressions, C), OS);
+}
+
+void CoverageMappingWriter::write(raw_ostream &OS) {
+ // Sort the regions in an ascending order by the file id and the starting
+ // location.
+ std::sort(MappingRegions.begin(), MappingRegions.end());
+
+ // Write out the fileid -> filename mapping.
+ encodeULEB128(VirtualFileMapping.size(), OS);
+ for (const auto &FileID : VirtualFileMapping)
+ encodeULEB128(FileID, OS);
+
+ // Write out the expressions.
+ CounterExpressionsMinimizer Minimizer(Expressions, MappingRegions);
+ auto MinExpressions = Minimizer.getExpressions();
+ encodeULEB128(MinExpressions.size(), OS);
+ for (const auto &E : MinExpressions) {
+ writeCounter(MinExpressions, Minimizer.adjust(E.LHS), OS);
+ writeCounter(MinExpressions, Minimizer.adjust(E.RHS), OS);
+ }
+
+ // Write out the mapping regions.
+ // Split the regions into subarrays where each region in a
+ // subarray has a fileID which is the index of that subarray.
+ unsigned PrevLineStart = 0;
+ unsigned CurrentFileID = MappingRegions.front().FileID;
+ assert(CurrentFileID == 0);
+ encodeULEB128(countFileIDs(MappingRegions, CurrentFileID), OS);
+ for (const auto &I : MappingRegions) {
+ if (I.FileID != CurrentFileID) {
+ // Ensure that all file ids have at least one mapping region.
+ assert(I.FileID == (CurrentFileID + 1));
+ // Start a new region sub-array.
+ CurrentFileID = I.FileID;
+ encodeULEB128(countFileIDs(MappingRegions, CurrentFileID), OS);
+ PrevLineStart = 0;
+ }
+ Counter Count = Minimizer.adjust(I.Count);
+ switch (I.Kind) {
+ case CounterMappingRegion::CodeRegion:
+ writeCounter(MinExpressions, Count, OS);
+ break;
+ case CounterMappingRegion::ExpansionRegion: {
+ assert(Count.isZero());
+ assert(I.ExpandedFileID <=
+ (std::numeric_limits<unsigned>::max() >>
+ Counter::EncodingCounterTagAndExpansionRegionTagBits));
+ // Mark an expansion region with a set bit that follows the counter tag,
+ // and pack the expanded file id into the remaining bits.
+ unsigned EncodedTagExpandedFileID =
+ (1 << Counter::EncodingTagBits) |
+ (I.ExpandedFileID
+ << Counter::EncodingCounterTagAndExpansionRegionTagBits);
+ encodeULEB128(EncodedTagExpandedFileID, OS);
+ break;
+ }
+ case CounterMappingRegion::EmptyRegion:
+ encodeULEB128(unsigned(I.Kind)
+ << Counter::EncodingCounterTagAndExpansionRegionTagBits,
+ OS);
+ break;
+ case CounterMappingRegion::SkippedRegion:
+ assert(Count.isZero());
+ encodeULEB128(unsigned(I.Kind)
+ << Counter::EncodingCounterTagAndExpansionRegionTagBits,
+ OS);
+ break;
+ }
+ assert(I.LineStart >= PrevLineStart);
+ encodeULEB128(I.LineStart - PrevLineStart, OS);
+ encodeULEB128(I.ColumnStart, OS);
+ assert(I.LineEnd >= I.LineStart);
+ encodeULEB128(I.LineEnd - I.LineStart, OS);
+ encodeULEB128(I.ColumnEnd, OS);
+ PrevLineStart = I.LineStart;
+ }
+ // Ensure that all file ids have at least one mapping region.
+ assert(CurrentFileID == (VirtualFileMapping.size() - 1));
+}
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