am 876d6995: Merge "Update aosp/master LLVM for rebase to r222494."

* commit '876d6995443e99d13696f3941c3a789a4daa7c7a':
  Update aosp/master LLVM for rebase to r222494.

1 files changed, 71 insertions, 29 deletions

diff --git a/lib/ProfileData/InstrProfReader.cpp b/lib/ProfileData/InstrProfReader.cpp
index 0b36728..0160a64 100644
--- a/lib/ProfileData/InstrProfReader.cpp
+++ b/lib/ProfileData/InstrProfReader.cpp
@@ -21,32 +21,34 @@
 
 using namespace llvm;
 
-static std::error_code
-setupMemoryBuffer(std::string Path, std::unique_ptr<MemoryBuffer> &Buffer) {
+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;
-  Buffer = std::move(BufferOrErr.get());
+  auto Buffer = std::move(BufferOrErr.get());
 
   // Sanity check the file.
   if (Buffer->getBufferSize() > std::numeric_limits<unsigned>::max())
     return instrprof_error::too_large;
-  return instrprof_error::success;
+  return std::move(Buffer);
 }
 
 static std::error_code initializeReader(InstrProfReader &Reader) {
   return Reader.readHeader();
 }
 
-std::error_code
-InstrProfReader::create(std::string Path,
-                        std::unique_ptr<InstrProfReader> &Result) {
+ErrorOr<std::unique_ptr<InstrProfReader>>
+InstrProfReader::create(std::string Path) {
   // Set up the buffer to read.
-  std::unique_ptr<MemoryBuffer> Buffer;
-  if (std::error_code EC = setupMemoryBuffer(Path, Buffer))
+  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)));
@@ -58,16 +60,20 @@ InstrProfReader::create(std::string Path,
     Result.reset(new TextInstrProfReader(std::move(Buffer)));
 
   // Initialize the reader and return the result.
-  return initializeReader(*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.
-  std::unique_ptr<MemoryBuffer> Buffer;
-  if (std::error_code EC = setupMemoryBuffer(Path, Buffer))
+  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;
@@ -83,8 +89,8 @@ void InstrProfIterator::Increment() {
 }
 
 std::error_code TextInstrProfReader::readNextRecord(InstrProfRecord &Record) {
-  // Skip empty lines.
-  while (!Line.is_at_end() && Line->empty())
+  // 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())
@@ -190,6 +196,9 @@ RawInstrProfReader<IntPtrT>::readNextHeader(const char *CurrentPos) {
   // 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>()))
@@ -307,8 +316,8 @@ std::error_code IndexedInstrProfReader::readHeader() {
     return error(instrprof_error::bad_magic);
 
   // Read the version.
-  uint64_t Version = endian::readNext<uint64_t, little, unaligned>(Cur);
-  if (Version != IndexedInstrProf::Version)
+  FormatVersion = endian::readNext<uint64_t, little, unaligned>(Cur);
+  if (FormatVersion > IndexedInstrProf::Version)
     return error(instrprof_error::unsupported_version);
 
   // Read the maximal function count.
@@ -331,18 +340,31 @@ std::error_code IndexedInstrProfReader::readHeader() {
 }
 
 std::error_code IndexedInstrProfReader::getFunctionCounts(
-    StringRef FuncName, uint64_t &FuncHash, std::vector<uint64_t> &Counts) {
-  const auto &Iter = Index->find(FuncName);
+    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. Make sure it's valid before giving back a result.
-  const InstrProfRecord &Record = *Iter;
-  if (Record.Name.empty())
-    return error(instrprof_error::malformed);
-  FuncHash = Record.Hash;
-  Counts = Record.Counts;
-  return success();
+  // 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
@@ -351,10 +373,30 @@ IndexedInstrProfReader::readNextRecord(InstrProfRecord &Record) {
   if (RecordIterator == Index->data_end())
     return error(instrprof_error::eof);
 
-  // Read the next one.
-  Record = *RecordIterator;
-  ++RecordIterator;
-  if (Record.Name.empty())
+  // 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();
 }