cpp11-migrate: Transforms collect timing data.

Using updated form of newFrontendActionFactory(), Transforms now automatically
measure, if requested, how long it takes to apply a MatchFinder to a source
file. Other per-transform overhead, e.g. applying replacements, is not
currently measured. This behaviour is disabled for now and soon will be
connected to a new command line arg.

llvm-svn: 182942

4 files changed, 66 insertions, 8 deletions

diff --git a/clang-tools-extra/cpp11-migrate/Core/Transform.cpp b/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
index d235356075f..c6bb835321d 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
@@ -35,3 +35,19 @@ void collectResults(clang::Rewriter &Rewrite,
     Results[Entry->getName()] = ResultBuf;
   }
 }
+
+bool Transform::handleBeginSource(CompilerInstance &CI, StringRef Filename) {
+  if (!EnableTiming)
+    return true;
+
+  Timings.push_back(std::make_pair(Filename.str(), llvm::TimeRecord()));
+  Timings.back().second -= llvm::TimeRecord::getCurrentTime(true);
+  return true;
+}
+
+void Transform::handleEndSource() {
+  if (!EnableTiming)
+    return;
+
+  Timings.back().second += llvm::TimeRecord::getCurrentTime(false);
+}
diff --git a/clang-tools-extra/cpp11-migrate/Core/Transform.h b/clang-tools-extra/cpp11-migrate/Core/Transform.h
index adc02989536..73a2a00a816 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transform.h
+++ b/clang-tools-extra/cpp11-migrate/Core/Transform.h
@@ -17,6 +17,8 @@
 
 #include <string>
 #include <vector>
+#include "clang/Tooling/Tooling.h"
+#include "llvm/Support/Timer.h"
 
 // For RewriterContainer
 #include "clang/Rewrite/Core/Rewriter.h"
@@ -104,9 +106,23 @@ private:
 };
 
 /// \brief Abstract base class for all C++11 migration transforms.
-class Transform {
+///
+/// Per-source performance timing is handled by the callbacks
+/// handleBeginSource() and handleEndSource() if timing is enabled. See
+/// clang::tooling::newFrontendActionFactory() for how to register
+/// a Transform object for callbacks.
+class Transform : public clang::tooling::SourceFileCallbacks {
 public:
-  Transform(llvm::StringRef Name) : Name(Name) {
+  /// \brief Constructor
+  /// \param Name Name of the transform for human-readable purposes (e.g. -help
+  /// text)
+  /// \param EnableTiming Enable the timing of the duration between calls to
+  /// handleBeginSource() and handleEndSource(). When a Transform object is
+  /// registered for FrontendAction source file callbacks, this behaviour can
+  /// be used to time the application of a MatchFinder by subclasses. Durations
+  /// are automatically stored in a TimingVec.
+  Transform(llvm::StringRef Name, bool EnableTiming)
+      : Name(Name), EnableTiming(EnableTiming) {
     Reset();
   }
 
@@ -156,7 +172,31 @@ public:
     DeferredChanges = 0;
   }
 
+  /// \brief Callback for notification of the start of processing of a source
+  /// file by a FrontendAction. Starts a performance timer if timing was
+  /// enabled.
+  virtual bool handleBeginSource(clang::CompilerInstance &CI,
+                                 llvm::StringRef Filename) LLVM_OVERRIDE;
+
+  /// \brief Callback for notification of the end of processing of a source
+  /// file by a FrontendAction. Stops a performance timer if timing was enabled
+  /// and records the elapsed time. For a given source, handleBeginSource() and
+  /// handleEndSource() are expected to be called in pairs.
+  virtual void handleEndSource() LLVM_OVERRIDE;
+
+  /// \brief Performance timing data is stored as a vector of pairs. Pairs are
+  /// formed of:
+  /// \li Name of source file.
+  /// \li Elapsed time.
+  typedef std::vector<std::pair<std::string, llvm::TimeRecord> > TimingVec;
+
+  /// \brief Return an iterator to the start of collected timing data.
+  TimingVec::const_iterator timing_begin() const { return Timings.begin(); }
+  /// \brief Return an iterator to the start of collected timing data.
+  TimingVec::const_iterator timing_end() const { return Timings.end(); }
+
 protected:
+
   void setAcceptedChanges(unsigned Changes) {
     AcceptedChanges = Changes;
   }
@@ -169,6 +209,8 @@ protected:
 
 private:
   const std::string Name;
+  bool EnableTiming;
+  TimingVec Timings;
   unsigned AcceptedChanges;
   unsigned RejectedChanges;
   unsigned DeferredChanges;
diff --git a/clang-tools-extra/cpp11-migrate/Core/Transforms.cpp b/clang-tools-extra/cpp11-migrate/Core/Transforms.cpp
index d7eae694870..85c0e2103a7 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transforms.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/Transforms.cpp
@@ -35,11 +35,11 @@ void Transforms::registerTransform(llvm::StringRef OptName,
       new cl::opt<bool>(OptName.data(), cl::desc(Description.data())), Creator));
 }
 
-void Transforms::createSelectedTransforms() {
+void Transforms::createSelectedTransforms(bool EnableTiming) {
   for (OptionVec::iterator I = Options.begin(),
        E = Options.end(); I != E; ++I) {
     if (*I->first) {
-      ChosenTransforms.push_back(I->second());
+      ChosenTransforms.push_back(I->second(EnableTiming));
     }
   }
 }
diff --git a/clang-tools-extra/cpp11-migrate/Core/Transforms.h b/clang-tools-extra/cpp11-migrate/Core/Transforms.h
index 67e38b025c8..b19b0316d90 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transforms.h
+++ b/clang-tools-extra/cpp11-migrate/Core/Transforms.h
@@ -28,10 +28,10 @@ class Option;
 } // namespace llvm
 class Transform;
 
-typedef Transform *(*TransformCreator)();
+typedef Transform *(*TransformCreator)(bool);
 template <typename T>
-Transform *ConstructTransform() {
-  return new T();
+Transform *ConstructTransform(bool EnableTiming) {
+  return new T(EnableTiming);
 }
 
 /// \brief Class encapsulating the creation of command line bool options
@@ -55,7 +55,7 @@ public:
   /// \brief Instantiate all transforms that were selected on the command line.
   ///
   /// Call *after* parsing options.
-  void createSelectedTransforms();
+  void createSelectedTransforms(bool EnableTiming);
 
   /// \brief Return an iterator to the start of a container of instantiated
   /// transforms.