Windows High-Precision and light Benchmark Class Implementation using PerformanceCounters

Benchmark.cpp

#include <Windows.h>

class Benchmark {
public:
	enum class Resolution {
		SEC   = 1,
		MILLI = 1000,
		MICRO = 1000000,
		NANO  = 1000000000
	};

	Benchmark(
        _In_ Resolution res = Resolution::MILLI
    )
		: m_res(res)
	{
		if (!m_liFrequenzy.QuadPart)
			QueryPerformanceFrequency(&m_liFrequenzy);
	}

	void Begin() {
		QueryPerformanceCounter(&m_liBegin);
	}
	uin64_t End() {
		QueryPerformanceCounter(&m_liEnd);

		// Calculate time difference, Whole/Part is to avoid integer overflows
		m_liEnd.QuadPart -= m_liBegin.QuadPart;
		uin64_t Whole = (m_liEnd.QuadPart / m_liFrequenzy.QuadPart) * (uint64)m_res;
		uin64_t Part = (m_liEnd.QuadPart % m_liFrequenzy.QuadPart) * (uint64)m_res;
		Part /= m_liFrequenzy.QuadPart;

		return Whole + Part;
	}

private:
	static LARGE_INTEGER m_liFrequenzy;
	const  Resolution    m_res;
	       LARGE_INTEGER m_liBegin;
	       LARGE_INTEGER m_liEnd;
};
LARGE_INTEGER Benchmark::m_liFrequenzy;