readTSC.C

////////////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2008 The Regents of the University of California
//
// This file is part of Qbox
//
// Qbox is distributed under the terms of the GNU General Public License
// as published by the Free Software Foundation, either version 2 of
// the License, or (at your option) any later version.
// See the file COPYING in the root directory of this distribution
// or <http://www.gnu.org/licenses/>.
//
///////////////////////////////////////////////////////////////////////////////
//
// readTSC.C
//
///////////////////////////////////////////////////////////////////////////////

long long readTSC(void)
{
  union { long long complete; unsigned int part[2]; } ticks;
  __asm__ ("rdtsc; mov %%eax,%0;mov %%edx,%1"
            : "=mr" (ticks.part[0]),
              "=mr" (ticks.part[1])
            : /* no inputs */
            : "eax", "edx");
  return ticks.complete;
}