81 lines
2.5 KiB
C++
Executable file
81 lines
2.5 KiB
C++
Executable file
// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
|
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
#if defined(_WIN32)
|
|
#include <windows.h>
|
|
#else
|
|
#include <time.h>
|
|
#endif
|
|
|
|
#include "common/steady_clock.h"
|
|
|
|
namespace Common {
|
|
|
|
#ifdef _WIN32
|
|
static s64 WindowsQueryPerformanceFrequency() {
|
|
LARGE_INTEGER frequency;
|
|
QueryPerformanceFrequency(&frequency);
|
|
return frequency.QuadPart;
|
|
}
|
|
|
|
static s64 WindowsQueryPerformanceCounter() {
|
|
LARGE_INTEGER counter;
|
|
QueryPerformanceCounter(&counter);
|
|
return counter.QuadPart;
|
|
}
|
|
|
|
static s64 GetSystemTimeNS() {
|
|
// GetSystemTimePreciseAsFileTime returns the file time in 100ns units.
|
|
static constexpr s64 Multiplier = 100;
|
|
// Convert Windows epoch to Unix epoch.
|
|
static constexpr s64 WindowsEpochToUnixEpochNS = 0x19DB1DED53E8000LL;
|
|
|
|
FILETIME filetime;
|
|
GetSystemTimePreciseAsFileTime(&filetime);
|
|
return Multiplier * ((static_cast<s64>(filetime.dwHighDateTime) << 32) +
|
|
static_cast<s64>(filetime.dwLowDateTime)) -
|
|
WindowsEpochToUnixEpochNS;
|
|
}
|
|
#endif
|
|
|
|
SteadyClock::time_point SteadyClock::Now() noexcept {
|
|
#if defined(_WIN32)
|
|
static const auto freq = WindowsQueryPerformanceFrequency();
|
|
const auto counter = WindowsQueryPerformanceCounter();
|
|
|
|
// 10 MHz is a very common QPC frequency on modern PCs.
|
|
// Optimizing for this specific frequency can double the performance of
|
|
// this function by avoiding the expensive frequency conversion path.
|
|
static constexpr s64 TenMHz = 10'000'000;
|
|
|
|
if (freq == TenMHz) [[likely]] {
|
|
static_assert(period::den % TenMHz == 0);
|
|
static constexpr s64 Multiplier = period::den / TenMHz;
|
|
return time_point{duration{counter * Multiplier}};
|
|
}
|
|
|
|
const auto whole = (counter / freq) * period::den;
|
|
const auto part = (counter % freq) * period::den / freq;
|
|
return time_point{duration{whole + part}};
|
|
#elif defined(__APPLE__)
|
|
return time_point{duration{clock_gettime_nsec_np(CLOCK_MONOTONIC_RAW)}};
|
|
#else
|
|
timespec ts;
|
|
clock_gettime(CLOCK_MONOTONIC, &ts);
|
|
return time_point{std::chrono::seconds{ts.tv_sec} + std::chrono::nanoseconds{ts.tv_nsec}};
|
|
#endif
|
|
}
|
|
|
|
RealTimeClock::time_point RealTimeClock::Now() noexcept {
|
|
#if defined(_WIN32)
|
|
return time_point{duration{GetSystemTimeNS()}};
|
|
#elif defined(__APPLE__)
|
|
return time_point{duration{clock_gettime_nsec_np(CLOCK_REALTIME)}};
|
|
#else
|
|
timespec ts;
|
|
clock_gettime(CLOCK_REALTIME, &ts);
|
|
return time_point{std::chrono::seconds{ts.tv_sec} + std::chrono::nanoseconds{ts.tv_nsec}};
|
|
#endif
|
|
}
|
|
|
|
}; // namespace Common
|