From 42c1c76f438498887b4646a7d42960f255c36c04 Mon Sep 17 00:00:00 2001
From: Sour <mesenemu@gmail.com>
Date: Sat, 15 Feb 2020 14:27:36 -0500
Subject: [PATCH] Refactoring: Port back some code changes from Mesen-S

---
 Core/Profiler.cpp   |  2 +-
 Utilities/Timer.cpp | 79 +++++----------------------------------------
 Utilities/Timer.h   | 22 ++++++-------
 3 files changed, 19 insertions(+), 84 deletions(-)

diff --git a/Core/Profiler.cpp b/Core/Profiler.cpp
index b2961dd6..20f7c686 100644
--- a/Core/Profiler.cpp
+++ b/Core/Profiler.cpp
@@ -7,7 +7,7 @@
 #include "MemoryManager.h"
 #include "MemoryDumper.h"
 #include "DebuggerTypes.h"
-#include "Cpu.h"
+#include "CPU.h"
 
 static constexpr int32_t ResetFunctionIndex = -1;
 
diff --git a/Utilities/Timer.cpp b/Utilities/Timer.cpp
index 9a155e1a..323aae6e 100644
--- a/Utilities/Timer.cpp
+++ b/Utilities/Timer.cpp
@@ -1,69 +1,29 @@
 #include "stdafx.h"
 #include "Timer.h"
 
-#ifndef LIBRETRO
-
 #include <thread>
+#include <chrono>
 
-#ifdef _WIN32
-#include <Windows.h>
+using namespace std::chrono;
 
-Timer::Timer() 
-{
-	LARGE_INTEGER li;
-	if(!QueryPerformanceFrequency(&li)) {
-		throw;
-	}
-
-	_frequency = double(li.QuadPart) / 1000.0;
-
-	QueryPerformanceCounter(&li);
-	_start = li.QuadPart;
-}
-
-void Timer::Reset()
-{
-	LARGE_INTEGER li;
-	QueryPerformanceCounter(&li);
-	_start = li.QuadPart;
-}
-
-double Timer::GetElapsedMS()
-{
-	LARGE_INTEGER li;
-	QueryPerformanceCounter(&li);
-	return double(li.QuadPart - _start) / _frequency;
-}
-
-#else 
-#include <time.h>
-
-Timer::Timer() 
+Timer::Timer()
 {
 	Reset();
 }
 
 void Timer::Reset()
 {
-	timespec start;
-	clock_gettime(CLOCK_MONOTONIC, &start);
-
-	_start = start.tv_sec * 1000000000 + start.tv_nsec;
+	_start = high_resolution_clock::now();
 }
 
 double Timer::GetElapsedMS()
 {
-	timespec end;
-	clock_gettime(CLOCK_MONOTONIC, &end);
-
-	uint64_t currentTime = end.tv_sec * 1000000000 + end.tv_nsec;
-	
-	return (double)(currentTime - _start) / 1000000.0;
+	high_resolution_clock::time_point end = high_resolution_clock::now();
+	duration<double> span = duration_cast<duration<double>>(end - _start);
+	return span.count() * 1000.0;
 }
 
-#endif
-
-void Timer::WaitUntil(double targetMillisecond) 
+void Timer::WaitUntil(double targetMillisecond)
 {
 	if(targetMillisecond > 0) {
 		double elapsedTime = GetElapsedMS();
@@ -72,26 +32,3 @@ void Timer::WaitUntil(double targetMillisecond)
 		}
 	}
 }
-
-#else 
-
-//This is not used by Libretro port, remove its dependencies
-
-Timer::Timer()
-{
-}
-
-void Timer::Reset()
-{
-}
-
-double Timer::GetElapsedMS()
-{
-	return 0.0;
-}
-
-void Timer::WaitUntil(double targetMillisecond)
-{
-}
-
-#endif
\ No newline at end of file
diff --git a/Utilities/Timer.h b/Utilities/Timer.h
index 5ed9fdda..f2f0f0c2 100644
--- a/Utilities/Timer.h
+++ b/Utilities/Timer.h
@@ -1,18 +1,16 @@
 #pragma once
 #include "stdafx.h"
+#include <chrono>
+using namespace std::chrono;
 
 class Timer
 {
-	private:
-#ifndef LIBRETRO
-		#ifdef _WIN32
-		double _frequency = 0.0;
-		#endif
-		uint64_t _start;
-#endif
-	public:
-		Timer();
-		void Reset();
-		double GetElapsedMS();
-		void WaitUntil(double targetMillisecond);
+private:
+	high_resolution_clock::time_point _start;
+
+public:
+	Timer();
+	void Reset();
+	double GetElapsedMS();
+	void WaitUntil(double targetMillisecond);
 };
\ No newline at end of file