InstrProf: Read raw binary profile in llvm-profdata

Read a raw binary profile that corresponds to a memory dump from the
runtime profile.

The test is a binary file generated from
cfe/trunk/test/Profile/c-general.c with the new compiler-rt runtime and
the matching text version of the input.  It includes instructions on how
to regenerate.

<rdar://problem/15950346>

llvm-svn: 204496

include/llvm/ProfileData/InstrProfReader.h

@@ -19,6 +19,7 @@
 #include "llvm/ProfileData/InstrProf.h"
 #include "llvm/Support/LineIterator.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Endian.h"
 
 #include <iterator>
 
@@ -59,20 +60,25 @@ public:
   InstrProfReader() : LastError(instrprof_error::success) {}
   virtual ~InstrProfReader() {}
 
+  /// Read the header.  Required before reading first record.
+  virtual error_code readHeader() = 0;
   /// Read a single record.
   virtual error_code readNextRecord(InstrProfRecord &Record) = 0;
   /// Iterator over profile data.
   InstrProfIterator begin() { return InstrProfIterator(this); }
   InstrProfIterator end() { return InstrProfIterator(); }
 
+protected:
   /// Set the current error_code and return same.
   error_code error(error_code EC) {
     LastError = EC;
     return EC;
   }
+
   /// Clear the current error code and return a successful one.
   error_code success() { return error(instrprof_error::success); }
 
+public:
   /// Return true if the reader has finished reading the profile data.
   bool isEOF() { return LastError == instrprof_error::eof; }
   /// Return true if the reader encountered an error reading profiling data.
@@ -110,10 +116,72 @@ public:
   TextInstrProfReader(std::unique_ptr<MemoryBuffer> &DataBuffer_)
       : DataBuffer(DataBuffer_.release()), Line(*DataBuffer, '#') {}
 
+  /// Read the header.
+  error_code readHeader() override { return success(); }
   /// Read a single record.
   error_code readNextRecord(InstrProfRecord &Record) override;
 };
 
+/// Reader for the raw instrprof binary format from runtime.
+///
+/// This format is a raw memory dump of the instrumentation-baed profiling data
+/// from the runtime.  It has no index.
+class RawInstrProfReader : public InstrProfReader {
+private:
+  /// The profile data file contents.
+  std::unique_ptr<MemoryBuffer> DataBuffer;
+  /// The current set of counter values.
+  std::vector<uint64_t> Counts;
+  struct ProfileData {
+    const uint32_t NameSize;
+    const uint32_t NumCounters;
+    const uint64_t FuncHash;
+    const uint64_t NamePtr;
+    const uint64_t CounterPtr;
+  };
+  struct RawHeader {
+    const uint64_t Magic;
+    const uint64_t Version;
+    const uint64_t DataSize;
+    const uint64_t CountersSize;
+    const uint64_t NamesSize;
+    const uint64_t CountersDelta;
+    const uint64_t NamesDelta;
+  };
+
+  bool ShouldSwapBytes;
+  uint64_t CountersDelta;
+  uint64_t NamesDelta;
+  const ProfileData *Data;
+  const ProfileData *DataEnd;
+  const uint64_t *CountersStart;
+  const char *NamesStart;
+
+  RawInstrProfReader(const TextInstrProfReader &) LLVM_DELETED_FUNCTION;
+  RawInstrProfReader &operator=(const TextInstrProfReader &)
+    LLVM_DELETED_FUNCTION;
+public:
+  RawInstrProfReader(std::unique_ptr<MemoryBuffer> &DataBuffer);
+
+  error_code readHeader() override;
+  error_code readNextRecord(InstrProfRecord &Record) override;
+
+private:
+  error_code readHeader(const RawHeader &Header);
+  template <class IntT>
+  IntT swap(IntT Int) const {
+    return ShouldSwapBytes ? sys::SwapByteOrder(Int) : Int;
+  }
+  const uint64_t *getCounter(uint64_t CounterPtr) const {
+    ptrdiff_t Offset = (swap(CounterPtr) - CountersDelta) / sizeof(uint64_t);
+    return CountersStart + Offset;
+  }
+  const char *getName(uint64_t NamePtr) const {
+    ptrdiff_t Offset = (swap(NamePtr) - NamesDelta) / sizeof(char);
+    return NamesStart + Offset;
+  }
+};
+
 } // end namespace llvm
 
 #endif // LLVM_PROFILEDATA_INSTRPROF_READER_H__

lib/ProfileData/InstrProfReader.cpp

@@ -14,12 +14,23 @@
 
 #include "llvm/ProfileData/InstrProfReader.h"
 #include "llvm/ProfileData/InstrProf.h"
-#include "llvm/Support/Endian.h"
 
 #include <cassert>
 
 using namespace llvm;
 
+static uint64_t getRawMagic() {
+  return
+    uint64_t('l') << 56 |
+    uint64_t('p') << 48 |
+    uint64_t('r') << 40 |
+    uint64_t('o') << 32 |
+    uint64_t('f') << 24 |
+    uint64_t('r') << 16 |
+    uint64_t('a') <<  8 |
+    uint64_t('w');
+}
+
 error_code InstrProfReader::create(std::string Path,
                                    std::unique_ptr<InstrProfReader> &Result) {
   std::unique_ptr<MemoryBuffer> Buffer;
@@ -30,10 +41,19 @@ error_code InstrProfReader::create(std::string Path,
   if (Buffer->getBufferSize() > std::numeric_limits<unsigned>::max())
     return instrprof_error::too_large;
 
-  // FIXME: This needs to determine which format the file is and construct the
-  // correct subclass.
-  Result.reset(new TextInstrProfReader(Buffer));
+  if (Buffer->getBufferSize() < sizeof(uint64_t)) {
+    Result.reset(new TextInstrProfReader(Buffer));
+    Result->readHeader();
+    return instrprof_error::success;
+  }
 
+  uint64_t Magic = *(uint64_t *)Buffer->getBufferStart();
+  uint64_t SwappedMagic = sys::SwapByteOrder(Magic);
+  if (Magic == getRawMagic() || SwappedMagic == getRawMagic())
+    Result.reset(new RawInstrProfReader(Buffer));
+  else
+    Result.reset(new TextInstrProfReader(Buffer));
+  Result->readHeader();
   return instrprof_error::success;
 }
 
@@ -82,3 +102,85 @@ error_code TextInstrProfReader::readNextRecord(InstrProfRecord &Record) {
 
   return success();
 }
+
+static uint64_t getRawVersion() {
+  return 1;
+}
+namespace {
+}
+RawInstrProfReader::RawInstrProfReader(std::unique_ptr<MemoryBuffer> &DataBuffer)
+    : DataBuffer(DataBuffer.release()) { }
+
+error_code RawInstrProfReader::readHeader() {
+  if (DataBuffer->getBufferSize() < sizeof(RawHeader))
+    return error(instrprof_error::malformed);
+  const RawHeader *Header = (RawHeader *)DataBuffer->getBufferStart();
+  if (Header->Magic == getRawMagic())
+    ShouldSwapBytes = false;
+  else {
+    if (sys::SwapByteOrder(Header->Magic) != getRawMagic())
+      return error(instrprof_error::malformed);
+
+    ShouldSwapBytes = true;
+  }
+  return readHeader(*Header);
+}
+
+error_code RawInstrProfReader::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 FileSize = NamesOffset + sizeof(char) * NamesSize;
+
+  if (FileSize != DataBuffer->getBufferSize())
+    return error(instrprof_error::malformed);
+
+  Data = (ProfileData *)(DataBuffer->getBufferStart() + DataOffset);
+  DataEnd = Data + DataSize;
+  CountersStart = (uint64_t *)(DataBuffer->getBufferStart() + CountersOffset);
+  NamesStart = DataBuffer->getBufferStart() + NamesOffset;
+
+  return success();
+}
+
+error_code RawInstrProfReader::readNextRecord(InstrProfRecord &Record) {
+  if (Data == DataEnd)
+    return error(instrprof_error::eof);
+
+  // Get the raw data.
+  StringRef RawName(getName(Data->NamePtr), swap(Data->NameSize));
+  auto RawCounts = makeArrayRef(getCounter(Data->CounterPtr),
+                                swap(Data->NumCounters));
+
+  // Check bounds.
+  if (RawName.data() < NamesStart ||
+      RawName.data() + RawName.size() > DataBuffer->getBufferEnd() ||
+      RawCounts.data() < CountersStart ||
+      RawCounts.data() + RawCounts.size() > (uint64_t *)NamesStart)
+    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();
+}

test/tools/llvm-profdata/Inputs/binary-compare.profdata

@@ -0,0 +1,150 @@
+simple_loops
+4
+4
+1
+100
+100
+75
+
+conditionals
+11
+11
+1
+100
+50
+50
+33
+33
+16
+99
+100
+99
+100
+
+early_exits
+9
+9
+1
+0
+51
+1
+25
+1
+25
+1
+0
+
+jumps
+22
+22
+1
+1
+0
+1
+0
+0
+1
+0
+1
+2
+3
+2
+0
+3
+0
+1
+1
+1
+10
+0
+10
+9
+
+switches
+19
+19
+1
+1
+1
+15
+7
+1
+0
+2
+2
+3
+3
+4
+4
+0
+4
+4
+5
+1
+0
+
+big_switch
+17
+17
+1
+32
+32
+1
+0
+1
+1
+11
+11
+1
+1
+15
+15
+1
+1
+2
+2
+
+boolean_operators
+8
+8
+1
+100
+34
+66
+17
+34
+33
+50
+
+boolop_loops
+9
+9
+1
+50
+51
+50
+26
+50
+51
+50
+26
+
+do_fallthrough
+4
+4
+1
+10
+2
+8
+
+main
+1
+1
+1
+
+c-general.c:static_func
+2
+2
+1
+10
+

test/tools/llvm-profdata/binary.test

@@ -0,0 +1,15 @@
+REGENERATE: You need a checkout of clang with compiler-rt to generate the
+REGENERATE: binary file here.  These shell commands can be used to regenerate
+REGENERATE: it.
+REGENERATE:
+REGENERATE: $ SRC=path/to/llvm
+REGENERATE: $ CFE=$SRC/tools/clang
+REGENERATE: $ TESTDIR=$SRC/test/tools/llvm-profdata
+REGENERATE: $ CFE_TESTDIR=$CFE/test/Profile
+REGENERATE: $ clang -o a.out -fprofile-instr-generate $CFE_TESTDIR/test/Profile/c-general.c
+REGENERATE: $ LLVM_PROFILE_FILE=$TESTDIR/Inputs/binary.profdata ./a.out
+REGENERATE: $ cp $CFE_TESTDIR/Inputs/c-general.profdata $TESTDIR/Inputs/binary-compare.profdata
+
+RUN: llvm-profdata show %p/Inputs/binary.profdata -o %t1
+RUN: llvm-profdata show %p/Inputs/binary-compare.profdata -o %t2
+RUN: diff -up %t1 %t2