SSE指令介绍及其C、C++应用(3)

              static __int64 nCurCount;

              QueryPerformanceCounter( (PLARGE_INTEGER)&nCurCount );

              return double( nCurCount * ( *(__int64*)&m_StartCount ) ) / double( *(__int64*)&m_Frequency );

       }

private:

       LARGE_INTEGER m_Frequency;

       LARGE_INTEGER m_StartCount;

};

void ScaleValue1( float *pArray, DWORD dwCount, float fScale )

{

       DWORD dwGroupCount = dwCount / 4;

       __m128 e_Scale = _mm_set_ps1( fScale );

       for ( DWORD i = 0; i < dwGroupCount; i++ )

       {

              *(__m128*)( pArray + i * 4 ) = _mm_mul_ps( *(__m128*)( pArray + i * 4 ), e_Scale );

       }

}

void ScaleValue2( float *pArray, DWORD dwCount, float fScale )

{

       for ( DWORD i = 0; i < dwCount; i++ )

       {

              pArray[i] *= fScale;

       }

}

#define ARRAYCOUNT 10000

int __cdecl main()

{

       float __declspec(align(16)) Array[ARRAYCOUNT];

       memset( Array, 0, sizeof(float) * ARRAYCOUNT );

       CTimer t;

       double dTime;

       t.Reset();