[core] Added HighResTimer for benchmarks.

base/timer.cpp

@@ -157,4 +157,20 @@ time_t StringToTimestamp(string const & s)
   return res;
 }
 
+HighResTimer::HighResTimer(bool start/* = true*/)
+{
+  if (start)
+    Reset();
+}
+
+void HighResTimer::Reset()
+{
+  m_start = high_resolution_clock::now();
+}
+
+uint64_t HighResTimer::ElapsedNano() const
+{
+  return duration_cast<nanoseconds>(high_resolution_clock::now() - m_start).count();
+}
+
 }

base/timer.hpp

@@ -3,6 +3,7 @@
 #include "../std/stdint.hpp"
 #include "../std/string.hpp"
 #include "../std/ctime.hpp"
+#include "../std/chrono.hpp"
 
 
 namespace my
@@ -37,4 +38,18 @@ time_t const INVALID_TIME_STAMP = -1;
 /// @return INVALID_TIME_STAMP if string is invalid
 time_t StringToTimestamp(string const & s);
 
+
+/// High resolution timer to use in comparison tests.
+class HighResTimer
+{
+  typedef high_resolution_clock::time_point PointT;
+  PointT m_start;
+
+public:
+  explicit HighResTimer(bool start = true);
+
+  void Reset();
+  uint64_t ElapsedNano() const;
+};
+
 }

std/chrono.hpp

@@ -0,0 +1,16 @@
+#pragma once
+#include "common_defines.hpp"
+
+#ifdef new
+#undef new
+#endif
+
+#include <chrono>
+
+using std::chrono::high_resolution_clock;
+using std::chrono::nanoseconds;
+using std::chrono::duration_cast;
+
+#ifdef DEBUG_NEW
+#define new DEBUG_NEW
+#endif