#if CV_AVX2

if( n >= 8 )

{

static const __m256d prescale4 = _mm256_set1_pd(exp_prescale);

static const __m256 postscale8 = _mm256_set1_ps((float)exp_postscale);

static const __m128 maxval4 = _mm_set1_ps((float)(exp_max_val/exp_prescale));

static const __m128 minval4 = _mm_set1_ps((float)(-exp_max_val/exp_prescale));

static const __m256 mA1 = _mm256_set1_ps(A1);

static const __m256 mA2 = _mm256_set1_ps(A2);

static const __m256 mA3 = _mm256_set1_ps(A3);

static const __m256 mA4 = _mm256_set1_ps(A4);

bool y_aligned = (size_t)(void*)y % 32 == 0;

ushort CV_DECL_ALIGNED(32) tab_idx[16];

for( ; i <= n - 8; i += 8 )

{

__m256 xf;

__m128i xi0, xi1;

__m256d xd0 = _mm256_cvtps_pd(_mm_min_ps(_mm_max_ps(_mm_loadu_ps(&x[i].f), minval4), maxval4));

__m256d xd1 = _mm256_cvtps_pd(_mm_min_ps(_mm_max_ps(_mm_loadu_ps(&x[i+4].f), minval4), maxval4));

xd0 = _mm256_mul_pd(xd0, prescale4);

xd1 = _mm256_mul_pd(xd1, prescale4);

xi0 = _mm256_cvtpd_epi32(xd0);

xi1 = _mm256_cvtpd_epi32(xd1);

xd0 = _mm256_sub_pd(xd0, _mm256_cvtepi32_pd(xi0));

xd1 = _mm256_sub_pd(xd1, _mm256_cvtepi32_pd(xi1));

// gcc does not support _mm256_set_m128

//xf = _mm256_set_m128(_mm256_cvtpd_ps(xd1), _mm256_cvtpd_ps(xd0));

xf = _mm256_insertf128_ps(xf, _mm256_cvtpd_ps(xd0), 0);

xf = _mm256_insertf128_ps(xf, _mm256_cvtpd_ps(xd1), 1);

xf = _mm256_mul_ps(xf, postscale8);

xi0 = _mm_packs_epi32(xi0, xi1);

_mm_store_si128((__m128i*)tab_idx, _mm_and_si128(xi0, _mm_set1_epi16(EXPTAB_MASK)));

xi0 = _mm_add_epi16(_mm_srai_epi16(xi0, EXPTAB_SCALE), _mm_set1_epi16(127));

xi0 = _mm_max_epi16(xi0, _mm_setzero_si128());

xi0 = _mm_min_epi16(xi0, _mm_set1_epi16(255));

xi1 = _mm_unpackhi_epi16(xi0, _mm_setzero_si128());

xi0 = _mm_unpacklo_epi16(xi0, _mm_setzero_si128());

__m256d yd0 = _mm256_set_pd(expTab[tab_idx[3]], expTab[tab_idx[2]], expTab[tab_idx[1]], expTab[tab_idx[0]]);

__m256d yd1 = _mm256_set_pd(expTab[tab_idx[7]], expTab[tab_idx[6]], expTab[tab_idx[5]], expTab[tab_idx[4]]);

// gcc does not support _mm256_set_m128

//__m256 yf = _mm256_set_m128(_mm256_cvtpd_ps(yd1), _mm256_cvtpd_ps(yd0));

__m256 yf;

yf = _mm256_insertf128_ps(yf, _mm256_cvtpd_ps(yd0), 0);

yf = _mm256_insertf128_ps(yf, _mm256_cvtpd_ps(yd1), 1);

//_mm256_set_m128i(xi1, xi0)

__m256i temp;

temp = _mm256_inserti128_si256(temp, xi0, 0);

temp = _mm256_inserti128_si256(temp, xi1, 1);

yf = _mm256_mul_ps(yf, _mm256_castsi256_ps(_mm256_slli_epi32(temp, 23)));

__m256 zf = _mm256_add_ps(xf, mA1);

#if CV_FMA3

zf = _mm256_fmadd_ps(zf, xf, mA2);

zf = _mm256_fmadd_ps(zf, xf, mA3);

zf = _mm256_fmadd_ps(zf, xf, mA4);

#else

zf = _mm256_add_ps(_mm256_mul_ps(zf, xf), mA2);

zf = _mm256_add_ps(_mm256_mul_ps(zf, xf), mA3);

zf = _mm256_add_ps(_mm256_mul_ps(zf, xf), mA4);

#endif

zf = _mm256_mul_ps(zf, yf);

if( y_aligned )

{

_mm256_store_ps(y + i, zf);

}

else

{

_mm256_storeu_ps(y + i, zf);

}

}

}

#elif CV_SSE2