ProfileData: Introduce the InstrProfReader interface and a text reader

This introduces the ProfileData library and updates llvm-profdata to
use this library for reading profiles. InstrProfReader is an abstract
base class that will be subclassed for both the raw instrprof data
from compiler-rt and the efficient instrprof format that will be used
for PGO.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204482 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 183 insertions, 0 deletions

diff --git a/lib/ProfileData/CMakeLists.txt b/lib/ProfileData/CMakeLists.txt
new file mode 100644
index 0000000000..cef3a5336b
--- /dev/null
+++ b/lib/ProfileData/CMakeLists.txt
@@ -0,0 +1,7 @@
+add_llvm_library(LLVMProfileData
+  InstrProf.cpp
+  InstrProfReader.cpp
+
+  LINK_LIBS
+  LLVMSupport
+)
diff --git a/lib/ProfileData/InstrProf.cpp b/lib/ProfileData/InstrProf.cpp
new file mode 100644
index 0000000000..329abf84e6
--- /dev/null
+++ b/lib/ProfileData/InstrProf.cpp
@@ -0,0 +1,56 @@
+//=-- InstrProf.cpp - Instrumented profiling format support -----------------=//
+//
+//                     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 instrumentation based PGO and
+// coverage.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ProfileData/InstrProf.h"
+#include "llvm/Support/ErrorHandling.h"
+
+using namespace llvm;
+
+namespace {
+class InstrProfErrorCategoryType : public error_category {
+  const char *name() const override { return "llvm.instrprof"; }
+  std::string message(int IE) const override {
+    instrprof_error::ErrorType E = static_cast<instrprof_error::ErrorType>(IE);
+    switch (E) {
+    case instrprof_error::success:
+      return "Success";
+    case instrprof_error::eof:
+      return "End of File";
+    case instrprof_error::bad_magic:
+      return "Invalid file format (bad magic)";
+    case instrprof_error::unsupported_version:
+      return "Unsupported format version";
+    case instrprof_error::too_large:
+      return "Too much profile data";
+    case instrprof_error::truncated:
+      return "Truncated profile data";
+    case instrprof_error::malformed:
+      return "Malformed profile data";
+    case instrprof_error::unknown_function:
+      return "No profile data available for function";
+    }
+    llvm_unreachable("A value of instrprof_error has no message.");
+  }
+  error_condition default_error_condition(int EV) const {
+    if (EV == instrprof_error::success)
+      return errc::success;
+    return errc::invalid_argument;
+  }
+};
+}
+
+const error_category &llvm::instrprof_category() {
+  static InstrProfErrorCategoryType C;
+  return C;
+}
diff --git a/lib/ProfileData/InstrProfReader.cpp b/lib/ProfileData/InstrProfReader.cpp
new file mode 100644
index 0000000000..8b3600090b
--- /dev/null
+++ b/lib/ProfileData/InstrProfReader.cpp
@@ -0,0 +1,84 @@
+//=-- 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 "llvm/ProfileData/InstrProf.h"
+#include "llvm/Support/Endian.h"
+
+#include <cassert>
+
+using namespace llvm;
+
+error_code InstrProfReader::create(std::string Path,
+                                   std::unique_ptr<InstrProfReader> &Result) {
+  std::unique_ptr<MemoryBuffer> Buffer;
+  if (error_code EC = MemoryBuffer::getFileOrSTDIN(Path, Buffer))
+    return EC;
+
+  // Sanity check the file.
+  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));
+
+  return instrprof_error::success;
+}
+
+void InstrProfIterator::Increment() {
+  if (Reader->readNextRecord(Record))
+    *this = InstrProfIterator();
+}
+
+error_code TextInstrProfReader::readNextRecord(InstrProfRecord &Record) {
+  // Skip empty lines.
+  while (!Line.is_at_end() && Line->empty())
+    ++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);
+
+  // 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();
+}
diff --git a/lib/ProfileData/LLVMBuild.txt b/lib/ProfileData/LLVMBuild.txt
new file mode 100644
index 0000000000..0a8cbe3363
--- /dev/null
+++ b/lib/ProfileData/LLVMBuild.txt
@@ -0,0 +1,22 @@
+;===- ./lib/ProfileData/LLVMBuild.txt --------------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[component_0]
+type = Library
+name = ProfileData
+parent = Libraries
+required_libraries = Support
diff --git a/lib/ProfileData/Makefile b/lib/ProfileData/Makefile
new file mode 100644
index 0000000000..26743612d3
--- /dev/null
+++ b/lib/ProfileData/Makefile
@@ -0,0 +1,14 @@
+##===- lib/ProfileData/Makefile ----------------------------*- Makefile -*-===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../..
+LIBRARYNAME = LLVMProfileData
+BUILD_ARCHIVE := 1
+
+include $(LEVEL)/Makefile.common