volk_32f_x3_sum_of_poly_32f.h

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/* -*- c++ -*- */
/*
 * Copyright 2012, 2014 Free Software Foundation, Inc.
 *
 * This file is part of VOLK
 *
 * SPDX-License-Identifier: LGPL-3.0-or-later
 */
 
#ifndef INCLUDED_volk_32f_x3_sum_of_poly_32f_a_H
#define INCLUDED_volk_32f_x3_sum_of_poly_32f_a_H
 
#include <inttypes.h>
#include <stdio.h>
#include <volk/volk_complex.h>
 
#ifndef MAX
#define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
#endif
 
#ifdef LV_HAVE_SSE3
#include <pmmintrin.h>
#include <xmmintrin.h>
 
static inline void volk_32f_x3_sum_of_poly_32f_a_sse3(float* target,
                                                      float* src0,
                                                      float* center_point_array,
                                                      float* cutoff,
                                                      unsigned int num_points)
{
    float result = 0.0f;
    float fst = 0.0f;
    float sq = 0.0f;
    float thrd = 0.0f;
    float frth = 0.0f;
 
    __m128 xmm0, xmm1, xmm2, xmm3, xmm4, xmm5, xmm6, xmm7, xmm8, xmm9, xmm10;
 
    xmm9 = _mm_setzero_ps();
    xmm1 = _mm_setzero_ps();
    xmm0 = _mm_load1_ps(&center_point_array[0]);
    xmm6 = _mm_load1_ps(&center_point_array[1]);
    xmm7 = _mm_load1_ps(&center_point_array[2]);
    xmm8 = _mm_load1_ps(&center_point_array[3]);
    xmm10 = _mm_load1_ps(cutoff);
 
    int bound = num_points / 8;
    int leftovers = num_points - 8 * bound;
    int i = 0;
    for (; i < bound; ++i) {
        // 1st
        xmm2 = _mm_load_ps(src0);
        xmm2 = _mm_max_ps(xmm10, xmm2);
        xmm3 = _mm_mul_ps(xmm2, xmm2);
        xmm4 = _mm_mul_ps(xmm2, xmm3);
        xmm5 = _mm_mul_ps(xmm3, xmm3);
 
        xmm2 = _mm_mul_ps(xmm2, xmm0);
        xmm3 = _mm_mul_ps(xmm3, xmm6);
        xmm4 = _mm_mul_ps(xmm4, xmm7);
        xmm5 = _mm_mul_ps(xmm5, xmm8);
 
        xmm2 = _mm_add_ps(xmm2, xmm3);
        xmm3 = _mm_add_ps(xmm4, xmm5);
 
        src0 += 4;
 
        xmm9 = _mm_add_ps(xmm2, xmm9);
        xmm9 = _mm_add_ps(xmm3, xmm9);
 
        // 2nd
        xmm2 = _mm_load_ps(src0);
        xmm2 = _mm_max_ps(xmm10, xmm2);
        xmm3 = _mm_mul_ps(xmm2, xmm2);
        xmm4 = _mm_mul_ps(xmm2, xmm3);
        xmm5 = _mm_mul_ps(xmm3, xmm3);
 
        xmm2 = _mm_mul_ps(xmm2, xmm0);
        xmm3 = _mm_mul_ps(xmm3, xmm6);
        xmm4 = _mm_mul_ps(xmm4, xmm7);
        xmm5 = _mm_mul_ps(xmm5, xmm8);
 
        xmm2 = _mm_add_ps(xmm2, xmm3);
        xmm3 = _mm_add_ps(xmm4, xmm5);
 
        src0 += 4;
 
        xmm1 = _mm_add_ps(xmm2, xmm1);
        xmm1 = _mm_add_ps(xmm3, xmm1);
    }
    xmm2 = _mm_hadd_ps(xmm9, xmm1);
    xmm3 = _mm_hadd_ps(xmm2, xmm2);
    xmm4 = _mm_hadd_ps(xmm3, xmm3);
    _mm_store_ss(&result, xmm4);
 
    for (i = 0; i < leftovers; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
        result += (center_point_array[0] * fst + center_point_array[1] * sq +
                   center_point_array[2] * thrd + center_point_array[3] * frth);
    }
 
    result += (float)(num_points)*center_point_array[4];
    *target = result;
}
 
 
#endif /*LV_HAVE_SSE3*/
 
#if LV_HAVE_AVX && LV_HAVE_FMA
#include <immintrin.h>
 
static inline void volk_32f_x3_sum_of_poly_32f_a_avx2_fma(float* target,
                                                          float* src0,
                                                          float* center_point_array,
                                                          float* cutoff,
                                                          unsigned int num_points)
{
    const unsigned int eighth_points = num_points / 8;
    float fst = 0.0;
    float sq = 0.0;
    float thrd = 0.0;
    float frth = 0.0;
 
    __m256 cpa0, cpa1, cpa2, cpa3, cutoff_vec;
    __m256 target_vec;
    __m256 x_to_1, x_to_2, x_to_3, x_to_4;
 
    cpa0 = _mm256_set1_ps(center_point_array[0]);
    cpa1 = _mm256_set1_ps(center_point_array[1]);
    cpa2 = _mm256_set1_ps(center_point_array[2]);
    cpa3 = _mm256_set1_ps(center_point_array[3]);
    cutoff_vec = _mm256_set1_ps(*cutoff);
    target_vec = _mm256_setzero_ps();
 
    unsigned int i;
 
    for (i = 0; i < eighth_points; ++i) {
        x_to_1 = _mm256_load_ps(src0);
        x_to_1 = _mm256_max_ps(x_to_1, cutoff_vec);
        x_to_2 = _mm256_mul_ps(x_to_1, x_to_1); // x^2
        x_to_3 = _mm256_mul_ps(x_to_1, x_to_2); // x^3
        // x^1 * x^3 is slightly faster than x^2 * x^2
        x_to_4 = _mm256_mul_ps(x_to_1, x_to_3); // x^4
 
        x_to_2 = _mm256_mul_ps(x_to_2, cpa1); // cpa[1] * x^2
        x_to_4 = _mm256_mul_ps(x_to_4, cpa3); // cpa[3] * x^4
 
        x_to_1 = _mm256_fmadd_ps(x_to_1, cpa0, x_to_2);
        x_to_3 = _mm256_fmadd_ps(x_to_3, cpa2, x_to_4);
        // this is slightly faster than result += (x_to_1 + x_to_3)
        target_vec = _mm256_add_ps(x_to_1, target_vec);
        target_vec = _mm256_add_ps(x_to_3, target_vec);
 
        src0 += 8;
    }
 
    // the hadd for vector reduction has very very slight impact @ 50k iters
    __VOLK_ATTR_ALIGNED(32) float temp_results[8];
    target_vec = _mm256_hadd_ps(
        target_vec,
        target_vec); // x0+x1 | x2+x3 | x0+x1 | x2+x3 || x4+x5 | x6+x7 | x4+x5 | x6+x7
    _mm256_store_ps(temp_results, target_vec);
    *target = temp_results[0] + temp_results[1] + temp_results[4] + temp_results[5];
 
    for (i = eighth_points * 8; i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
        *target += (center_point_array[0] * fst + center_point_array[1] * sq +
                    center_point_array[2] * thrd + center_point_array[3] * frth);
    }
    *target += (float)(num_points)*center_point_array[4];
}
#endif // LV_HAVE_AVX && LV_HAVE_FMA
 
#ifdef LV_HAVE_AVX
#include <immintrin.h>
 
static inline void volk_32f_x3_sum_of_poly_32f_a_avx(float* target,
                                                     float* src0,
                                                     float* center_point_array,
                                                     float* cutoff,
                                                     unsigned int num_points)
{
    const unsigned int eighth_points = num_points / 8;
    float fst = 0.0;
    float sq = 0.0;
    float thrd = 0.0;
    float frth = 0.0;
 
    __m256 cpa0, cpa1, cpa2, cpa3, cutoff_vec;
    __m256 target_vec;
    __m256 x_to_1, x_to_2, x_to_3, x_to_4;
 
    cpa0 = _mm256_set1_ps(center_point_array[0]);
    cpa1 = _mm256_set1_ps(center_point_array[1]);
    cpa2 = _mm256_set1_ps(center_point_array[2]);
    cpa3 = _mm256_set1_ps(center_point_array[3]);
    cutoff_vec = _mm256_set1_ps(*cutoff);
    target_vec = _mm256_setzero_ps();
 
    unsigned int i;
 
    for (i = 0; i < eighth_points; ++i) {
        x_to_1 = _mm256_load_ps(src0);
        x_to_1 = _mm256_max_ps(x_to_1, cutoff_vec);
        x_to_2 = _mm256_mul_ps(x_to_1, x_to_1); // x^2
        x_to_3 = _mm256_mul_ps(x_to_1, x_to_2); // x^3
        // x^1 * x^3 is slightly faster than x^2 * x^2
        x_to_4 = _mm256_mul_ps(x_to_1, x_to_3); // x^4
 
        x_to_1 = _mm256_mul_ps(x_to_1, cpa0); // cpa[0] * x^1
        x_to_2 = _mm256_mul_ps(x_to_2, cpa1); // cpa[1] * x^2
        x_to_3 = _mm256_mul_ps(x_to_3, cpa2); // cpa[2] * x^3
        x_to_4 = _mm256_mul_ps(x_to_4, cpa3); // cpa[3] * x^4
 
        x_to_1 = _mm256_add_ps(x_to_1, x_to_2);
        x_to_3 = _mm256_add_ps(x_to_3, x_to_4);
        // this is slightly faster than result += (x_to_1 + x_to_3)
        target_vec = _mm256_add_ps(x_to_1, target_vec);
        target_vec = _mm256_add_ps(x_to_3, target_vec);
 
        src0 += 8;
    }
 
    // the hadd for vector reduction has very very slight impact @ 50k iters
    __VOLK_ATTR_ALIGNED(32) float temp_results[8];
    target_vec = _mm256_hadd_ps(
        target_vec,
        target_vec); // x0+x1 | x2+x3 | x0+x1 | x2+x3 || x4+x5 | x6+x7 | x4+x5 | x6+x7
    _mm256_store_ps(temp_results, target_vec);
    *target = temp_results[0] + temp_results[1] + temp_results[4] + temp_results[5];
 
    for (i = eighth_points * 8; i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
        *target += (center_point_array[0] * fst + center_point_array[1] * sq +
                    center_point_array[2] * thrd + center_point_array[3] * frth);
    }
    *target += (float)(num_points)*center_point_array[4];
}
#endif // LV_HAVE_AVX
 
 
#ifdef LV_HAVE_GENERIC
 
static inline void volk_32f_x3_sum_of_poly_32f_generic(float* target,
                                                       float* src0,
                                                       float* center_point_array,
                                                       float* cutoff,
                                                       unsigned int num_points)
{
    const unsigned int eighth_points = num_points / 8;
 
    float result[8] = { 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
    float fst = 0.0f;
    float sq = 0.0f;
    float thrd = 0.0f;
    float frth = 0.0f;
 
    unsigned int i = 0;
    unsigned int k = 0;
    for (i = 0; i < eighth_points; ++i) {
        for (k = 0; k < 8; ++k) {
            fst = *src0++;
            fst = MAX(fst, *cutoff);
            sq = fst * fst;
            thrd = fst * sq;
            frth = fst * thrd;
            result[k] += center_point_array[0] * fst + center_point_array[1] * sq;
            result[k] += center_point_array[2] * thrd + center_point_array[3] * frth;
        }
    }
    for (k = 0; k < 8; k += 2)
        result[k] = result[k] + result[k + 1];
 
    *target = result[0] + result[2] + result[4] + result[6];
 
    for (i = eighth_points * 8; i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = fst * thrd;
        *target += (center_point_array[0] * fst + center_point_array[1] * sq +
                    center_point_array[2] * thrd + center_point_array[3] * frth);
    }
    *target += (float)(num_points)*center_point_array[4];
}
 
#endif /*LV_HAVE_GENERIC*/
 
#ifdef LV_HAVE_NEON
#include <arm_neon.h>
 
static inline void
volk_32f_x3_sum_of_poly_32f_a_neon(float* __restrict target,
                                   float* __restrict src0,
                                   float* __restrict center_point_array,
                                   float* __restrict cutoff,
                                   unsigned int num_points)
{
    unsigned int i;
    float zero[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
 
    float32x2_t x_to_1, x_to_2, x_to_3, x_to_4;
    float32x2_t cutoff_vector;
    float32x2x2_t x_low, x_high;
    float32x4_t x_qvector, c_qvector, cpa_qvector;
    float accumulator;
    float res_accumulators[4];
 
    c_qvector = vld1q_f32(zero);
    // load the cutoff in to a vector
    cutoff_vector = vdup_n_f32(*cutoff);
    // ... center point array
    cpa_qvector = vld1q_f32(center_point_array);
 
    for (i = 0; i < num_points; ++i) {
        // load x  (src0)
        x_to_1 = vdup_n_f32(*src0++);
 
        // Get a vector of max(src0, cutoff)
        x_to_1 = vmax_f32(x_to_1, cutoff_vector); // x^1
        x_to_2 = vmul_f32(x_to_1, x_to_1);        // x^2
        x_to_3 = vmul_f32(x_to_2, x_to_1);        // x^3
        x_to_4 = vmul_f32(x_to_3, x_to_1);        // x^4
        // zip up doubles to interleave
        x_low = vzip_f32(x_to_1, x_to_2);  // [x^2 | x^1 || x^2 | x^1]
        x_high = vzip_f32(x_to_3, x_to_4); // [x^4 | x^3 || x^4 | x^3]
        // float32x4_t vcombine_f32(float32x2_t low, float32x2_t high); // VMOV d0,d0
        x_qvector = vcombine_f32(x_low.val[0], x_high.val[0]);
        // now we finally have [x^4 | x^3 | x^2 | x] !
 
        c_qvector = vmlaq_f32(c_qvector, x_qvector, cpa_qvector);
    }
    // there should be better vector reduction techniques
    vst1q_f32(res_accumulators, c_qvector);
    accumulator = res_accumulators[0] + res_accumulators[1] + res_accumulators[2] +
                  res_accumulators[3];
 
    *target = accumulator + (float)num_points * center_point_array[4];
}
 
#endif /* LV_HAVE_NEON */
 
 
#ifdef LV_HAVE_NEON
 
static inline void
volk_32f_x3_sum_of_poly_32f_neonvert(float* __restrict target,
                                     float* __restrict src0,
                                     float* __restrict center_point_array,
                                     float* __restrict cutoff,
                                     unsigned int num_points)
{
    unsigned int i;
    float zero[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
 
    float accumulator;
 
    float32x4_t accumulator1_vec, accumulator2_vec, accumulator3_vec, accumulator4_vec;
    accumulator1_vec = vld1q_f32(zero);
    accumulator2_vec = vld1q_f32(zero);
    accumulator3_vec = vld1q_f32(zero);
    accumulator4_vec = vld1q_f32(zero);
    float32x4_t x_to_1, x_to_2, x_to_3, x_to_4;
    float32x4_t cutoff_vector, cpa_0, cpa_1, cpa_2, cpa_3;
 
    // load the cutoff in to a vector
    cutoff_vector = vdupq_n_f32(*cutoff);
    // ... center point array
    cpa_0 = vdupq_n_f32(center_point_array[0]);
    cpa_1 = vdupq_n_f32(center_point_array[1]);
    cpa_2 = vdupq_n_f32(center_point_array[2]);
    cpa_3 = vdupq_n_f32(center_point_array[3]);
 
    // nathan is not sure why this is slower *and* wrong compared to neonvertfma
    for (i = 0; i < num_points / 4; ++i) {
        // load x
        x_to_1 = vld1q_f32(src0);
 
        // Get a vector of max(src0, cutoff)
        x_to_1 = vmaxq_f32(x_to_1, cutoff_vector); // x^1
        x_to_2 = vmulq_f32(x_to_1, x_to_1);        // x^2
        x_to_3 = vmulq_f32(x_to_2, x_to_1);        // x^3
        x_to_4 = vmulq_f32(x_to_3, x_to_1);        // x^4
        x_to_1 = vmulq_f32(x_to_1, cpa_0);
        x_to_2 = vmulq_f32(x_to_2, cpa_1);
        x_to_3 = vmulq_f32(x_to_3, cpa_2);
        x_to_4 = vmulq_f32(x_to_4, cpa_3);
        accumulator1_vec = vaddq_f32(accumulator1_vec, x_to_1);
        accumulator2_vec = vaddq_f32(accumulator2_vec, x_to_2);
        accumulator3_vec = vaddq_f32(accumulator3_vec, x_to_3);
        accumulator4_vec = vaddq_f32(accumulator4_vec, x_to_4);
 
        src0 += 4;
    }
    accumulator1_vec = vaddq_f32(accumulator1_vec, accumulator2_vec);
    accumulator3_vec = vaddq_f32(accumulator3_vec, accumulator4_vec);
    accumulator1_vec = vaddq_f32(accumulator1_vec, accumulator3_vec);
 
    __VOLK_ATTR_ALIGNED(32) float res_accumulators[4];
    vst1q_f32(res_accumulators, accumulator1_vec);
    accumulator = res_accumulators[0] + res_accumulators[1] + res_accumulators[2] +
                  res_accumulators[3];
 
    float fst = 0.0;
    float sq = 0.0;
    float thrd = 0.0;
    float frth = 0.0;
 
    for (i = 4 * (num_points / 4); i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
 
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
        // fith = sq * thrd;
 
        accumulator += (center_point_array[0] * fst + center_point_array[1] * sq +
                        center_point_array[2] * thrd + center_point_array[3] * frth); //+
    }
 
    *target = accumulator + (float)num_points * center_point_array[4];
}
 
#endif /* LV_HAVE_NEON */
 
#endif /*INCLUDED_volk_32f_x3_sum_of_poly_32f_a_H*/
 
#ifndef INCLUDED_volk_32f_x3_sum_of_poly_32f_u_H
#define INCLUDED_volk_32f_x3_sum_of_poly_32f_u_H
 
#include <inttypes.h>
#include <stdio.h>
#include <volk/volk_complex.h>
 
#ifndef MAX
#define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
#endif
 
#if LV_HAVE_AVX && LV_HAVE_FMA
#include <immintrin.h>
 
static inline void volk_32f_x3_sum_of_poly_32f_u_avx_fma(float* target,
                                                         float* src0,
                                                         float* center_point_array,
                                                         float* cutoff,
                                                         unsigned int num_points)
{
    const unsigned int eighth_points = num_points / 8;
    float fst = 0.0;
    float sq = 0.0;
    float thrd = 0.0;
    float frth = 0.0;
 
    __m256 cpa0, cpa1, cpa2, cpa3, cutoff_vec;
    __m256 target_vec;
    __m256 x_to_1, x_to_2, x_to_3, x_to_4;
 
    cpa0 = _mm256_set1_ps(center_point_array[0]);
    cpa1 = _mm256_set1_ps(center_point_array[1]);
    cpa2 = _mm256_set1_ps(center_point_array[2]);
    cpa3 = _mm256_set1_ps(center_point_array[3]);
    cutoff_vec = _mm256_set1_ps(*cutoff);
    target_vec = _mm256_setzero_ps();
 
    unsigned int i;
 
    for (i = 0; i < eighth_points; ++i) {
        x_to_1 = _mm256_loadu_ps(src0);
        x_to_1 = _mm256_max_ps(x_to_1, cutoff_vec);
        x_to_2 = _mm256_mul_ps(x_to_1, x_to_1); // x^2
        x_to_3 = _mm256_mul_ps(x_to_1, x_to_2); // x^3
        // x^1 * x^3 is slightly faster than x^2 * x^2
        x_to_4 = _mm256_mul_ps(x_to_1, x_to_3); // x^4
 
        x_to_2 = _mm256_mul_ps(x_to_2, cpa1); // cpa[1] * x^2
        x_to_4 = _mm256_mul_ps(x_to_4, cpa3); // cpa[3] * x^4
 
        x_to_1 = _mm256_fmadd_ps(x_to_1, cpa0, x_to_2);
        x_to_3 = _mm256_fmadd_ps(x_to_3, cpa2, x_to_4);
        // this is slightly faster than result += (x_to_1 + x_to_3)
        target_vec = _mm256_add_ps(x_to_1, target_vec);
        target_vec = _mm256_add_ps(x_to_3, target_vec);
 
        src0 += 8;
    }
 
    // the hadd for vector reduction has very very slight impact @ 50k iters
    __VOLK_ATTR_ALIGNED(32) float temp_results[8];
    target_vec = _mm256_hadd_ps(
        target_vec,
        target_vec); // x0+x1 | x2+x3 | x0+x1 | x2+x3 || x4+x5 | x6+x7 | x4+x5 | x6+x7
    _mm256_storeu_ps(temp_results, target_vec);
    *target = temp_results[0] + temp_results[1] + temp_results[4] + temp_results[5];
 
    for (i = eighth_points * 8; i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
        *target += (center_point_array[0] * fst + center_point_array[1] * sq +
                    center_point_array[2] * thrd + center_point_array[3] * frth);
    }
 
    *target += (float)(num_points)*center_point_array[4];
}
#endif // LV_HAVE_AVX && LV_HAVE_FMA
 
#ifdef LV_HAVE_AVX
#include <immintrin.h>
 
static inline void volk_32f_x3_sum_of_poly_32f_u_avx(float* target,
                                                     float* src0,
                                                     float* center_point_array,
                                                     float* cutoff,
                                                     unsigned int num_points)
{
    const unsigned int eighth_points = num_points / 8;
    float fst = 0.0;
    float sq = 0.0;
    float thrd = 0.0;
    float frth = 0.0;
 
    __m256 cpa0, cpa1, cpa2, cpa3, cutoff_vec;
    __m256 target_vec;
    __m256 x_to_1, x_to_2, x_to_3, x_to_4;
 
    cpa0 = _mm256_set1_ps(center_point_array[0]);
    cpa1 = _mm256_set1_ps(center_point_array[1]);
    cpa2 = _mm256_set1_ps(center_point_array[2]);
    cpa3 = _mm256_set1_ps(center_point_array[3]);
    cutoff_vec = _mm256_set1_ps(*cutoff);
    target_vec = _mm256_setzero_ps();
 
    unsigned int i;
 
    for (i = 0; i < eighth_points; ++i) {
        x_to_1 = _mm256_loadu_ps(src0);
        x_to_1 = _mm256_max_ps(x_to_1, cutoff_vec);
        x_to_2 = _mm256_mul_ps(x_to_1, x_to_1); // x^2
        x_to_3 = _mm256_mul_ps(x_to_1, x_to_2); // x^3
        // x^1 * x^3 is slightly faster than x^2 * x^2
        x_to_4 = _mm256_mul_ps(x_to_1, x_to_3); // x^4
 
        x_to_1 = _mm256_mul_ps(x_to_1, cpa0); // cpa[0] * x^1
        x_to_2 = _mm256_mul_ps(x_to_2, cpa1); // cpa[1] * x^2
        x_to_3 = _mm256_mul_ps(x_to_3, cpa2); // cpa[2] * x^3
        x_to_4 = _mm256_mul_ps(x_to_4, cpa3); // cpa[3] * x^4
 
        x_to_1 = _mm256_add_ps(x_to_1, x_to_2);
        x_to_3 = _mm256_add_ps(x_to_3, x_to_4);
        // this is slightly faster than result += (x_to_1 + x_to_3)
        target_vec = _mm256_add_ps(x_to_1, target_vec);
        target_vec = _mm256_add_ps(x_to_3, target_vec);
 
        src0 += 8;
    }
 
    // the hadd for vector reduction has very very slight impact @ 50k iters
    __VOLK_ATTR_ALIGNED(32) float temp_results[8];
    target_vec = _mm256_hadd_ps(
        target_vec,
        target_vec); // x0+x1 | x2+x3 | x0+x1 | x2+x3 || x4+x5 | x6+x7 | x4+x5 | x6+x7
    _mm256_storeu_ps(temp_results, target_vec);
    *target = temp_results[0] + temp_results[1] + temp_results[4] + temp_results[5];
 
    for (i = eighth_points * 8; i < num_points; ++i) {
        fst = *src0++;
        fst = MAX(fst, *cutoff);
        sq = fst * fst;
        thrd = fst * sq;
        frth = sq * sq;
 
        *target += (center_point_array[0] * fst + center_point_array[1] * sq +
                    center_point_array[2] * thrd + center_point_array[3] * frth);
    }
 
    *target += (float)(num_points)*center_point_array[4];
}
#endif // LV_HAVE_AVX
 
#endif /*INCLUDED_volk_32f_x3_sum_of_poly_32f_u_H*/