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// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.


#ifndef BASE_PROFILER_SCOPED_PROFILE_H_
#define BASE_PROFILER_SCOPED_PROFILE_H_

//------------------------------------------------------------------------------
// ScopedProfile provides basic helper functions for profiling a short
// region of code within a scope.  It is separate from the related ThreadData
// class so that it can be included without much other cruft, and provide the
// macros listed below.

#include "base/base_export.h"
#include "base/location.h"
#include "base/profiler/tracked_time.h"
#include "base/tracked_objects.h"

#define PASTE_LINE_NUMBER_ON_NAME(name, line) name##line

#define LINE_BASED_VARIABLE_NAME_FOR_PROFILING                                 \
    PASTE_LINE_NUMBER_ON_NAME(some_profiler_variable_, __LINE__)

// Defines the containing scope as a profiled region. This allows developers to
// profile their code and see results on their about:profiler page, as well as
// on the UMA dashboard.
#define TRACK_RUN_IN_THIS_SCOPED_REGION(dispatch_function_name)                \
    ::tracked_objects::ScopedProfile LINE_BASED_VARIABLE_NAME_FOR_PROFILING(   \
        FROM_HERE_WITH_EXPLICIT_FUNCTION(#dispatch_function_name))


namespace tracked_objects {
class Births;

class BASE_EXPORT ScopedProfile {
 public:
  explicit ScopedProfile(const Location& location);
  ~ScopedProfile();

  // Stop tracing prior to the end destruction of the instance.
  void StopClockAndTally();

 private:
  Births* birth_;  // Place in code where tracking started.
  TaskStopwatch stopwatch_;

  DISALLOW_COPY_AND_ASSIGN(ScopedProfile);
};

}  // namespace tracked_objects

#endif   // BASE_PROFILER_SCOPED_PROFILE_H_