diff options
Diffstat (limited to 'tools/timer/SysTimer_windows.cpp')
-rw-r--r-- | tools/timer/SysTimer_windows.cpp | 53 |
1 files changed, 0 insertions, 53 deletions
diff --git a/tools/timer/SysTimer_windows.cpp b/tools/timer/SysTimer_windows.cpp deleted file mode 100644 index 8e45b4a68e..0000000000 --- a/tools/timer/SysTimer_windows.cpp +++ /dev/null @@ -1,53 +0,0 @@ -/* - * Copyright 2011 Google Inc. - * - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ -#include "SysTimer_windows.h" - -#include <intrin.h> - -static ULONGLONG win_cpu_time() { - FILETIME createTime; - FILETIME exitTime; - FILETIME usrTime; - FILETIME sysTime; - if (0 == GetProcessTimes(GetCurrentProcess(), &createTime, &exitTime, &sysTime, &usrTime)) { - return 0; - } - ULARGE_INTEGER start_cpu_sys; - ULARGE_INTEGER start_cpu_usr; - start_cpu_sys.LowPart = sysTime.dwLowDateTime; - start_cpu_sys.HighPart = sysTime.dwHighDateTime; - start_cpu_usr.LowPart = usrTime.dwLowDateTime; - start_cpu_usr.HighPart = usrTime.dwHighDateTime; - return start_cpu_sys.QuadPart + start_cpu_usr.QuadPart; -} - -void SysTimer::startCpu() { - fStartCpu = win_cpu_time(); -} - -double SysTimer::endCpu() { - ULONGLONG end_cpu = win_cpu_time(); - return static_cast<double>(end_cpu - fStartCpu) / 10000.0L; -} - -// On recent Intel chips (roughly, "has Core or Atom in its name") __rdtsc will always tick -// at the CPU's maximum rate, even while power management clocks the CPU up and down. -// That's great, because it makes measuring wall time super simple. - -void SysTimer::startWall() { - fStartWall = __rdtsc(); -} - -double SysTimer::endWall() { - unsigned __int64 end = __rdtsc(); - - // This seems to, weirdly, give the CPU frequency in kHz. That's exactly what we want! - LARGE_INTEGER freq_khz; - QueryPerformanceFrequency(&freq_khz); - - return static_cast<double>(end - fStartWall) / static_cast<double>(freq_khz.QuadPart); -} |