1 files changed, 400 insertions, 0 deletions
diff --git a/contrib/llvm/lib/ProfileData/InstrProfReader.cpp b/contrib/llvm/lib/ProfileData/InstrProfReader.cpp
new file mode 100644
index 0000000..31ed130
--- /dev/null
+++ b/contrib/llvm/lib/ProfileData/InstrProfReader.cpp
@@ -0,0 +1,400 @@
+//=-- InstrProfReader.cpp - Instrumented profiling reader -------------------=//
+//
+//                     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 profiling data for clang's
+// instrumentation based PGO and coverage.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ProfileData/InstrProfReader.h"
+#include "InstrProfIndexed.h"
+#include "llvm/ProfileData/InstrProf.h"
+#include <cassert>
+
+using namespace llvm;
+
+static ErrorOr<std::unique_ptr<MemoryBuffer>>
+setupMemoryBuffer(std::string Path) {
+  ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+      MemoryBuffer::getFileOrSTDIN(Path);
+  if (std::error_code EC = BufferOrErr.getError())
+    return EC;
+  auto Buffer = std::move(BufferOrErr.get());
+
+  // Sanity check the file.
+  if (Buffer->getBufferSize() > std::numeric_limits<unsigned>::max())
+    return instrprof_error::too_large;
+  return std::move(Buffer);
+}
+
+static std::error_code initializeReader(InstrProfReader &Reader) {
+  return Reader.readHeader();
+}
+
+ErrorOr<std::unique_ptr<InstrProfReader>>
+InstrProfReader::create(std::string Path) {
+  // Set up the buffer to read.
+  auto BufferOrError = setupMemoryBuffer(Path);
+  if (std::error_code EC = BufferOrError.getError())
+    return EC;
+
+  auto Buffer = std::move(BufferOrError.get());
+  std::unique_ptr<InstrProfReader> Result;
+
+  // Create the reader.
+  if (IndexedInstrProfReader::hasFormat(*Buffer))
+    Result.reset(new IndexedInstrProfReader(std::move(Buffer)));
+  else if (RawInstrProfReader64::hasFormat(*Buffer))
+    Result.reset(new RawInstrProfReader64(std::move(Buffer)));
+  else if (RawInstrProfReader32::hasFormat(*Buffer))
+    Result.reset(new RawInstrProfReader32(std::move(Buffer)));
+  else
+    Result.reset(new TextInstrProfReader(std::move(Buffer)));
+
+  // Initialize the reader and return the result.
+  if (std::error_code EC = initializeReader(*Result))
+    return EC;
+
+  return std::move(Result);
+}
+
+std::error_code IndexedInstrProfReader::create(
+    std::string Path, std::unique_ptr<IndexedInstrProfReader> &Result) {
+  // Set up the buffer to read.
+  auto BufferOrError = setupMemoryBuffer(Path);
+  if (std::error_code EC = BufferOrError.getError())
+    return EC;
+
+  auto Buffer = std::move(BufferOrError.get());
+  // Create the reader.
+  if (!IndexedInstrProfReader::hasFormat(*Buffer))
+    return instrprof_error::bad_magic;
+  Result.reset(new IndexedInstrProfReader(std::move(Buffer)));
+
+  // Initialize the reader and return the result.
+  return initializeReader(*Result);
+}
+
+void InstrProfIterator::Increment() {
+  if (Reader->readNextRecord(Record))
+    *this = InstrProfIterator();
+}
+
+std::error_code TextInstrProfReader::readNextRecord(InstrProfRecord &Record) {
+  // Skip empty lines and comments.
+  while (!Line.is_at_end() && (Line->empty() || Line->startswith("#")))
+    ++Line;
+  // If we hit EOF while looking for a name, we're done.
+  if (Line.is_at_end())
+    return error(instrprof_error::eof);
+
+  // Read the function name.
+  Record.Name = *Line++;
+
+  // Read the function hash.
+  if (Line.is_at_end())
+    return error(instrprof_error::truncated);
+  if ((Line++)->getAsInteger(10, Record.Hash))
+    return error(instrprof_error::malformed);
+
+  // Read the number of counters.
+  uint64_t NumCounters;
+  if (Line.is_at_end())
+    return error(instrprof_error::truncated);
+  if ((Line++)->getAsInteger(10, NumCounters))
+    return error(instrprof_error::malformed);
+  if (NumCounters == 0)
+    return error(instrprof_error::malformed);
+
+  // Read each counter and fill our internal storage with the values.
+  Counts.clear();
+  Counts.reserve(NumCounters);
+  for (uint64_t I = 0; I < NumCounters; ++I) {
+    if (Line.is_at_end())
+      return error(instrprof_error::truncated);
+    uint64_t Count;
+    if ((Line++)->getAsInteger(10, Count))
+      return error(instrprof_error::malformed);
+    Counts.push_back(Count);
+  }
+  // Give the record a reference to our internal counter storage.
+  Record.Counts = Counts;
+
+  return success();
+}
+
+template <class IntPtrT>
+static uint64_t getRawMagic();
+
+template <>
+uint64_t getRawMagic<uint64_t>() {
+  return
+    uint64_t(255) << 56 |
+    uint64_t('l') << 48 |
+    uint64_t('p') << 40 |
+    uint64_t('r') << 32 |
+    uint64_t('o') << 24 |
+    uint64_t('f') << 16 |
+    uint64_t('r') <<  8 |
+    uint64_t(129);
+}
+
+template <>
+uint64_t getRawMagic<uint32_t>() {
+  return
+    uint64_t(255) << 56 |
+    uint64_t('l') << 48 |
+    uint64_t('p') << 40 |
+    uint64_t('r') << 32 |
+    uint64_t('o') << 24 |
+    uint64_t('f') << 16 |
+    uint64_t('R') <<  8 |
+    uint64_t(129);
+}
+
+template <class IntPtrT>
+bool RawInstrProfReader<IntPtrT>::hasFormat(const MemoryBuffer &DataBuffer) {
+  if (DataBuffer.getBufferSize() < sizeof(uint64_t))
+    return false;
+  uint64_t Magic =
+    *reinterpret_cast<const uint64_t *>(DataBuffer.getBufferStart());
+  return getRawMagic<IntPtrT>() == Magic ||
+    sys::getSwappedBytes(getRawMagic<IntPtrT>()) == Magic;
+}
+
+template <class IntPtrT>
+std::error_code RawInstrProfReader<IntPtrT>::readHeader() {
+  if (!hasFormat(*DataBuffer))
+    return error(instrprof_error::bad_magic);
+  if (DataBuffer->getBufferSize() < sizeof(RawHeader))
+    return error(instrprof_error::bad_header);
+  auto *Header =
+    reinterpret_cast<const RawHeader *>(DataBuffer->getBufferStart());
+  ShouldSwapBytes = Header->Magic != getRawMagic<IntPtrT>();
+  return readHeader(*Header);
+}
+
+template <class IntPtrT>
+std::error_code
+RawInstrProfReader<IntPtrT>::readNextHeader(const char *CurrentPos) {
+  const char *End = DataBuffer->getBufferEnd();
+  // Skip zero padding between profiles.
+  while (CurrentPos != End && *CurrentPos == 0)
+    ++CurrentPos;
+  // If there's nothing left, we're done.
+  if (CurrentPos == End)
+    return instrprof_error::eof;
+  // If there isn't enough space for another header, this is probably just
+  // garbage at the end of the file.
+  if (CurrentPos + sizeof(RawHeader) > End)
+    return instrprof_error::malformed;
+  // The writer ensures each profile is padded to start at an aligned address.
+  if (reinterpret_cast<size_t>(CurrentPos) % alignOf<uint64_t>())
+    return instrprof_error::malformed;
+  // The magic should have the same byte order as in the previous header.
+  uint64_t Magic = *reinterpret_cast<const uint64_t *>(CurrentPos);
+  if (Magic != swap(getRawMagic<IntPtrT>()))
+    return instrprof_error::bad_magic;
+
+  // There's another profile to read, so we need to process the header.
+  auto *Header = reinterpret_cast<const RawHeader *>(CurrentPos);
+  return readHeader(*Header);
+}
+
+static uint64_t getRawVersion() {
+  return 1;
+}
+
+template <class IntPtrT>
+std::error_code
+RawInstrProfReader<IntPtrT>::readHeader(const RawHeader &Header) {
+  if (swap(Header.Version) != getRawVersion())
+    return error(instrprof_error::unsupported_version);
+
+  CountersDelta = swap(Header.CountersDelta);
+  NamesDelta = swap(Header.NamesDelta);
+  auto DataSize = swap(Header.DataSize);
+  auto CountersSize = swap(Header.CountersSize);
+  auto NamesSize = swap(Header.NamesSize);
+
+  ptrdiff_t DataOffset = sizeof(RawHeader);
+  ptrdiff_t CountersOffset = DataOffset + sizeof(ProfileData) * DataSize;
+  ptrdiff_t NamesOffset = CountersOffset + sizeof(uint64_t) * CountersSize;
+  size_t ProfileSize = NamesOffset + sizeof(char) * NamesSize;
+
+  auto *Start = reinterpret_cast<const char *>(&Header);
+  if (Start + ProfileSize > DataBuffer->getBufferEnd())
+    return error(instrprof_error::bad_header);
+
+  Data = reinterpret_cast<const ProfileData *>(Start + DataOffset);
+  DataEnd = Data + DataSize;
+  CountersStart = reinterpret_cast<const uint64_t *>(Start + CountersOffset);
+  NamesStart = Start + NamesOffset;
+  ProfileEnd = Start + ProfileSize;
+
+  return success();
+}
+
+template <class IntPtrT>
+std::error_code
+RawInstrProfReader<IntPtrT>::readNextRecord(InstrProfRecord &Record) {
+  if (Data == DataEnd)
+    if (std::error_code EC = readNextHeader(ProfileEnd))
+      return EC;
+
+  // Get the raw data.
+  StringRef RawName(getName(Data->NamePtr), swap(Data->NameSize));
+  uint32_t NumCounters = swap(Data->NumCounters);
+  if (NumCounters == 0)
+    return error(instrprof_error::malformed);
+  auto RawCounts = makeArrayRef(getCounter(Data->CounterPtr), NumCounters);
+
+  // Check bounds.
+  auto *NamesStartAsCounter = reinterpret_cast<const uint64_t *>(NamesStart);
+  if (RawName.data() < NamesStart ||
+      RawName.data() + RawName.size() > DataBuffer->getBufferEnd() ||
+      RawCounts.data() < CountersStart ||
+      RawCounts.data() + RawCounts.size() > NamesStartAsCounter)
+    return error(instrprof_error::malformed);
+
+  // Store the data in Record, byte-swapping as necessary.
+  Record.Hash = swap(Data->FuncHash);
+  Record.Name = RawName;
+  if (ShouldSwapBytes) {
+    Counts.clear();
+    Counts.reserve(RawCounts.size());
+    for (uint64_t Count : RawCounts)
+      Counts.push_back(swap(Count));
+    Record.Counts = Counts;
+  } else
+    Record.Counts = RawCounts;
+
+  // Iterate.
+  ++Data;
+  return success();
+}
+
+namespace llvm {
+template class RawInstrProfReader<uint32_t>;
+template class RawInstrProfReader<uint64_t>;
+}
+
+InstrProfLookupTrait::hash_value_type
+InstrProfLookupTrait::ComputeHash(StringRef K) {
+  return IndexedInstrProf::ComputeHash(HashType, K);
+}
+
+bool IndexedInstrProfReader::hasFormat(const MemoryBuffer &DataBuffer) {
+  if (DataBuffer.getBufferSize() < 8)
+    return false;
+  using namespace support;
+  uint64_t Magic =
+      endian::read<uint64_t, little, aligned>(DataBuffer.getBufferStart());
+  return Magic == IndexedInstrProf::Magic;
+}
+
+std::error_code IndexedInstrProfReader::readHeader() {
+  const unsigned char *Start =
+      (const unsigned char *)DataBuffer->getBufferStart();
+  const unsigned char *Cur = Start;
+  if ((const unsigned char *)DataBuffer->getBufferEnd() - Cur < 24)
+    return error(instrprof_error::truncated);
+
+  using namespace support;
+
+  // Check the magic number.
+  uint64_t Magic = endian::readNext<uint64_t, little, unaligned>(Cur);
+  if (Magic != IndexedInstrProf::Magic)
+    return error(instrprof_error::bad_magic);
+
+  // Read the version.
+  FormatVersion = endian::readNext<uint64_t, little, unaligned>(Cur);
+  if (FormatVersion > IndexedInstrProf::Version)
+    return error(instrprof_error::unsupported_version);
+
+  // Read the maximal function count.
+  MaxFunctionCount = endian::readNext<uint64_t, little, unaligned>(Cur);
+
+  // Read the hash type and start offset.
+  IndexedInstrProf::HashT HashType = static_cast<IndexedInstrProf::HashT>(
+      endian::readNext<uint64_t, little, unaligned>(Cur));
+  if (HashType > IndexedInstrProf::HashT::Last)
+    return error(instrprof_error::unsupported_hash_type);
+  uint64_t HashOffset = endian::readNext<uint64_t, little, unaligned>(Cur);
+
+  // The rest of the file is an on disk hash table.
+  Index.reset(InstrProfReaderIndex::Create(Start + HashOffset, Cur, Start,
+                                           InstrProfLookupTrait(HashType)));
+  // Set up our iterator for readNextRecord.
+  RecordIterator = Index->data_begin();
+
+  return success();
+}
+
+std::error_code IndexedInstrProfReader::getFunctionCounts(
+    StringRef FuncName, uint64_t FuncHash, std::vector<uint64_t> &Counts) {
+  auto Iter = Index->find(FuncName);
+  if (Iter == Index->end())
+    return error(instrprof_error::unknown_function);
+
+  // Found it. Look for counters with the right hash.
+  ArrayRef<uint64_t> Data = (*Iter).Data;
+  uint64_t NumCounts;
+  for (uint64_t I = 0, E = Data.size(); I != E; I += NumCounts) {
+    // The function hash comes first.
+    uint64_t FoundHash = Data[I++];
+    // In v1, we have at least one count. Later, we have the number of counts.
+    if (I == E)
+      return error(instrprof_error::malformed);
+    NumCounts = FormatVersion == 1 ? E - I : Data[I++];
+    // If we have more counts than data, this is bogus.
+    if (I + NumCounts > E)
+      return error(instrprof_error::malformed);
+    // Check for a match and fill the vector if there is one.
+    if (FoundHash == FuncHash) {
+      Counts = Data.slice(I, NumCounts);
+      return success();
+    }
+  }
+  return error(instrprof_error::hash_mismatch);
+}
+
+std::error_code
+IndexedInstrProfReader::readNextRecord(InstrProfRecord &Record) {
+  // Are we out of records?
+  if (RecordIterator == Index->data_end())
+    return error(instrprof_error::eof);
+
+  // Record the current function name.
+  Record.Name = (*RecordIterator).Name;
+
+  ArrayRef<uint64_t> Data = (*RecordIterator).Data;
+  // Valid data starts with a hash and either a count or the number of counts.
+  if (CurrentOffset + 1 > Data.size())
+    return error(instrprof_error::malformed);
+  // First we have a function hash.
+  Record.Hash = Data[CurrentOffset++];
+  // In version 1 we knew the number of counters implicitly, but in newer
+  // versions we store the number of counters next.
+  uint64_t NumCounts =
+      FormatVersion == 1 ? Data.size() - CurrentOffset : Data[CurrentOffset++];
+  if (CurrentOffset + NumCounts > Data.size())
+    return error(instrprof_error::malformed);
+  // And finally the counts themselves.
+  Record.Counts = Data.slice(CurrentOffset, NumCounts);
+
+  // If we've exhausted this function's data, increment the record.
+  CurrentOffset += NumCounts;
+  if (CurrentOffset == Data.size()) {
+    ++RecordIterator;
+    CurrentOffset = 0;
+  }
+
+  return success();
+}