// Copyright 2019 Google LLC
//
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree.

#include <assert.h>

#include <xnnpack/avgpool.h>
#include <xnnpack/math.h>


void xnn_f32_avgpool_ukernel_up9__scalar(
    size_t n,
    size_t ks,
    size_t kc,
    const float** input,
    const float* zero,
    float* output,
    size_t input_increment,
    size_t output_increment,
    const union xnn_f32_avgpool_params params[restrict static 1])
{
  assert(n != 0);
  assert(ks != 0);
  assert(ks <= 9);
  assert(kc != 0);

  const float vmultiplier = params->scalar.multiplier;
  const float voutput_min = params->scalar.output_min;
  const float voutput_max = params->scalar.output_max;

  do {
    const float* i0 = input[0];
    const float* i1 = input[1];
    const float* i2 = input[2];
    const float* i3 = input[3];
    const float* i4 = input[4];
    const float* i5 = input[5];
    const float* i6 = input[6];
    const float* i7 = input[7];
    const float* i8 = input[8];
    input = (const float**) ((uintptr_t) input + input_increment);
    if (ks < 2) {
      i1 = zero;
    }
    if (ks <= 2) {
      i2 = zero;
    }
    if (ks < 4) {
      i3 = zero;
    }
    if (ks <= 4) {
      i4 = zero;
    }
    if (ks < 6) {
      i5 = zero;
    }
    if (ks <= 6) {
      i6 = zero;
    }
    if (ks < 8) {
      i7 = zero;
    }
    if (ks <= 8) {
      i8 = zero;
    }

    size_t k = kc;
    do {
      const float vi0 = *i0++;
      const float vi1 = *i1++;
      const float vi2 = *i2++;
      const float vi3 = *i3++;
      const float vi4 = *i4++;
      const float vi5 = *i5++;
      const float vi6 = *i6++;
      const float vi7 = *i7++;
      const float vi8 = *i8++;

      const float vsum01 = vi0 + vi1;
      const float vsum23 = vi2 + vi3;
      const float vsum45 = vi4 + vi5;
      const float vsum67 = vi6 + vi7;
      const float vsum018 = vsum01 + vi8;
      const float vsum2345 = vsum23 + vsum45;
      const float vsum01678 = vsum018 + vsum67;
      const float vsum = vsum2345 + vsum01678;

      float vout = vsum * vmultiplier;
      vout = math_max_f32(vout, voutput_min);
      vout = math_min_f32(vout, voutput_max);

      *output++ = vout;
    } while (--k != 0);
    output = (float*) ((uintptr_t) output + output_increment);
  } while (--n != 0);
}