added explicit access to cycle count

src/aion/Tracer.hh

@@ -91,6 +91,17 @@ struct visitor
 
 void visit_thread(visitor& v);
 
+#ifdef _WIN32
+inline uint64_t current_cycles() { return __rdtsc(); }
+#else //  Linux/GCC
+inline uint64_t current_cycles()
+{
+    unsigned int lo, hi;
+    __asm__ __volatile__("rdtsc" : "=a"(lo), "=d"(hi));
+    return ((uint64_t)hi << 32) | lo;
+}
+#endif
+
 /// writes all trace points to a json file
 /// Format:
 /// {
@@ -201,6 +212,6 @@ struct raii_profiler
         pd[3] = core;
     }
 };
-}
-}
-}
+} // namespace detail
+} // namespace tracing
+} // namespace aion