// 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.

$assert CHANNEL_TILE % 4 == 0
$assert CHANNEL_TILE >= 4
$assert ROW_TILE >= 1
$ABC = "0123456789ABCDEFGHIJKLMN"
#include <assert.h>

#include <psimd.h>

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


void xnn_f32_prelu_ukernel__psimd_${ROW_TILE}x${CHANNEL_TILE}(
    size_t rows,
    size_t channels,
    const float*restrict input,
    size_t input_stride,
    const float*restrict weights,
    float*restrict output,
    size_t output_stride,
    const union xnn_f32_output_params params[restrict static 1])
{
  assert(rows != 0);
  assert(channels != 0);
  assert(channels % sizeof(float) == 0);

  const float* i0 = input;
  float* o0 = output;
  $for M in range(1, ROW_TILE):
    const float* i${M} = (const float*) ((uintptr_t) i${M-1} + input_stride);
    float* o${M} = (float*) ((uintptr_t) o${M-1} + output_stride);
    $if M % 2 == 0:
      if XNN_UNPREDICTABLE(rows <= ${M}) {
        i${M} = i${M-1};
        o${M} = o${M-1};
      }
    $else:
      if XNN_UNPREDICTABLE(rows < ${M+1}) {
        i${M} = i${M-1};
        o${M} = o${M-1};
      }

  const size_t input_increment = input_stride * ${ROW_TILE} - channels;
  const size_t output_increment = output_stride * ${ROW_TILE} - channels;

  const psimd_f32 vmin = psimd_load_splat_f32(&params->scalar.min);
  const psimd_f32 vmax = psimd_load_splat_f32(&params->scalar.max);
  do {
    const float* w = weights;
    size_t c = channels;
    for (; c >= ${CHANNEL_TILE} * sizeof(float); c -= ${CHANNEL_TILE} * sizeof(float)) {
      const psimd_f32 vw${ABC[0:4]} = psimd_load_f32(w);
      $for C in range(4, CHANNEL_TILE, 4):
        const psimd_f32 vw${ABC[C:C+4]} = psimd_load_f32(w + ${C});
      w += ${CHANNEL_TILE};

      $for M in range(ROW_TILE):
        const psimd_f32 vi${M}x${ABC[0:4]} = psimd_load_f32(i${M});
        $for C in range(4, CHANNEL_TILE, 4):
          const psimd_f32 vi${M}x${ABC[C:C+4]} = psimd_load_f32(i${M} + ${C});
        i${M} += ${CHANNEL_TILE};

      $for M in range(ROW_TILE):
        $for C in range(0, CHANNEL_TILE, 4):
          psimd_f32 vacc${M}x${ABC[C:C+4]} = psimd_mul_f32(vi${M}x${ABC[C:C+4]}, vw${ABC[C:C+4]});

      $for M in range(ROW_TILE):
        $for C in range(0, CHANNEL_TILE, 4):
          vacc${M}x${ABC[C:C+4]} = psimd_signblend_f32(vi${M}x${ABC[C:C+4]}, vacc${M}x${ABC[C:C+4]}, vi${M}x${ABC[C:C+4]});

      $for M in range(ROW_TILE):
        $for C in range(0, CHANNEL_TILE, 4):
          vacc${M}x${ABC[C:C+4]} = psimd_max_f32(vacc${M}x${ABC[C:C+4]}, vmin);

      $for M in range(ROW_TILE):
        $for C in range(0, CHANNEL_TILE, 4):
          vacc${M}x${ABC[C:C+4]} = psimd_min_f32(vacc${M}x${ABC[C:C+4]}, vmax);

      $for M in range(ROW_TILE):
        psimd_store_f32(o${M}, vacc${M}x${ABC[0:4]});
        $for C in range(4, CHANNEL_TILE, 4):
          psimd_store_f32(o${M} + ${C}, vacc${M}x${ABC[C:C+4]});
        o${M} += ${CHANNEL_TILE};
    }
    $if CHANNEL_TILE > 4:
      for (; c >= 4 * sizeof(float); c -= 4 * sizeof(float)) {
        const psimd_f32 vw0123 = psimd_load_f32(w);
        w += 4;

        $for M in range(ROW_TILE):
          const psimd_f32 vi${M}x0123 = psimd_load_f32(i${M});
          i${M} += 4;

        $for M in range(ROW_TILE):
          psimd_f32 vacc${M}x0123 = psimd_mul_f32(vi${M}x0123, vw0123);

        $for M in range(ROW_TILE):
          vacc${M}x0123 = psimd_signblend_f32(vi${M}x0123, vacc${M}x0123, vi${M}x0123);

        $for M in range(ROW_TILE):
          vacc${M}x0123 = psimd_max_f32(vacc${M}x0123, vmin);

        $for M in range(ROW_TILE):
          vacc${M}x0123 = psimd_min_f32(vacc${M}x0123, vmax);

        $for M in range(ROW_TILE):
          psimd_store_f32(o${M}, vacc${M}x0123);
          o${M} += 4;
      }
    if XNN_UNLIKELY(c != 0) {
      const psimd_f32 vw0123 = psimd_load_f32(w);
      w = (const float*) ((uintptr_t) w + c);

      $for M in range(ROW_TILE):
        const psimd_f32 vi${M}x0123 = psimd_load_f32(i${M});
        i${M} = (const float*) ((uintptr_t) i${M} + c);

      $for M in range(ROW_TILE):
        psimd_f32 vacc${M}x0123 = psimd_mul_f32(vi${M}x0123, vw0123);

      $for M in range(ROW_TILE):
        vacc${M}x0123 = psimd_signblend_f32(vi${M}x0123, vacc${M}x0123, vi${M}x0123);

      $for M in range(ROW_TILE):
        vacc${M}x0123 = psimd_max_f32(vacc${M}x0123, vmin);

      $for M in range(ROW_TILE):
        vacc${M}x0123 = psimd_min_f32(vacc${M}x0123, vmax);

      if (c & (2 * sizeof(float))) {
        $for M in range(ROW_TILE):
          psimd_store2_f32(o${M}, vacc${M}x0123);

        $for M in range(ROW_TILE):
          vacc${M}x0123 = psimd_concat_hi_f32(vacc${M}x0123, vacc${M}x0123);

        $for M in range(ROW_TILE):
          o${M} += 2;
      }
      if (c & (1 * sizeof(float))) {
        $for M in range(ROW_TILE):
          psimd_store1_f32(o${M}, vacc${M}x0123);

        $for M in range(ROW_TILE):
          o${M} += 1;
      }
    }
    $for M in range(ROW_TILE):
      i${M} = (const float*) ((uintptr_t) i${M} + input_increment);
      o${M} = (float*) ((uintptr_t) o${M} + output_increment);
      $if M % 2 == 1:
        if XNN_UNPREDICTABLE(rows < ${ROW_TILE + M+1}) {
          i${M} = i${M-1};
          o${M} = o${M-1};
        }
      $elif M != 0:
        if XNN_UNPREDICTABLE(rows <= ${ROW_TILE + M}) {
          i${M} = i${M-1};
          o${M} = o${M-1};
        }
    rows = doz(rows, ${ROW_TILE});
  } while (rows != 0);
}