// Copyright 2021 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 SSE in [2, 4]
$assert DATATYPE in ["QS8", "QU8"]
$assert BATCH_TILE % 8 == 0
$assert BATCH_TILE >= 8
$SSE_HEADER = {2: "emmintrin.h", 4: "smmintrin.h"}[SSE]
$ABC = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#include <assert.h>

#include <${SSE_HEADER}>

#include <xnnpack/common.h>
#include <xnnpack/unaligned.h>
#include <xnnpack/vcvt.h>


$ISA = {2: "sse2", 4: "sse41"}[SSE]
$XINT8_T = {"QS8": "int8_t", "QU8": "uint8_t"}[DATATYPE]
$_MM_PACKXS_EPI16 = {"QS8": "_mm_packs_epi16", "QU8": "_mm_packus_epi16"}[DATATYPE]
$_MM_MAX_EPX8 = {"QS8": "_mm_max_epi8", "QU8": "_mm_max_epu8"}[DATATYPE]
void xnn_f32_${DATATYPE.lower()}_vcvt_ukernel__${ISA}_x${BATCH_TILE}(
    size_t n,
    const float* x,
    ${XINT8_T}* y,
    const union xnn_f32_${DATATYPE.lower()}_cvt_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_OOB_READS
{
  assert(n != 0);
  assert(n % sizeof(float) == 0);
  assert(x != NULL);
  assert(y != NULL);

  const __m128 vscale = _mm_load_ps(params->sse${SSE}.scale);
  const __m128 voutput_max_less_zero_point = _mm_load_ps(params->sse${SSE}.output_max_less_zero_point);
  const __m128i voutput_zero_point = _mm_load_si128((const __m128i*) params->sse${SSE}.output_zero_point);
  const __m128i voutput_min = _mm_load_si128((const __m128i*) params->sse${SSE}.output_min);

  $if BATCH_TILE > 8:
    for (; n >= ${BATCH_TILE} * sizeof(float); n -= ${BATCH_TILE} * sizeof(float)) {
      __m128 vx${ABC[0:4]} = _mm_loadu_ps(x);
      $for N in range(4, BATCH_TILE, 4):
        __m128 vx${ABC[N:N+4]} = _mm_loadu_ps(x + ${N});
      x += ${BATCH_TILE};

      $for N in range(0, BATCH_TILE, 4):
        vx${ABC[N:N+4]} = _mm_mul_ps(vx${ABC[N:N+4]}, vscale);

      $for N in range(0, BATCH_TILE, 4):
        vx${ABC[N:N+4]} = _mm_min_ps(vx${ABC[N:N+4]}, voutput_max_less_zero_point);

      $for N in range(0, BATCH_TILE, 4):
        const __m128i vy${ABC[N:N+4]} = _mm_cvtps_epi32(vx${ABC[N:N+4]});

      $for N in range(0, BATCH_TILE, 8):
        __m128i vy${ABC[N:N+8]} = _mm_packs_epi32(vy${ABC[N:N+4]}, vy${ABC[N+4:N+8]});

      $for N in range(0, BATCH_TILE, 8):
        vy${ABC[N:N+8]} = _mm_adds_epi16(vy${ABC[N:N+8]}, voutput_zero_point);

      $if DATATYPE == "QS8" and SSE < 4:
        $for N in range(0, BATCH_TILE, 8):
          vy${ABC[N:N+8]} = _mm_max_epi16(vy${ABC[N:N+8]}, voutput_min);

      $for N in range(0, BATCH_TILE, 16):
        $if N + 8 < BATCH_TILE:
          __m128i vy${ABC[N:N+16]} = ${_MM_PACKXS_EPI16}(vy${ABC[N:N+8]}, vy${ABC[N+8:N+16]});
        $else:
          vy${ABC[N:N+8]} = ${_MM_PACKXS_EPI16}(vy${ABC[N:N+8]}, vy${ABC[N:N+8]});

      $if DATATYPE == "QU8" or SSE == 4:
        $for N in range(0, BATCH_TILE, 16):
          $if N + 8 < BATCH_TILE:
            vy${ABC[N:N+16]} = ${_MM_MAX_EPX8}(vy${ABC[N:N+16]}, voutput_min);
          $else:
            vy${ABC[N:N+8]} = ${_MM_MAX_EPX8}(vy${ABC[N:N+8]}, voutput_min);

      _mm_storeu_si128((__m128i*) y, vy${ABC[0:16]});
      $for N in range(16, BATCH_TILE, 16):
        $if N + 8 < BATCH_TILE:
          _mm_storeu_si128((__m128i*) (y + ${N}), vy${ABC[N:N+16]});
        $else:
          _mm_storel_epi64((__m128i*) (y + ${N}), vy${ABC[N:N+8]});
      y += ${BATCH_TILE};
    }
  for (; n >= 8 * sizeof(float); n -= 8 * sizeof(float)) {
    __m128 vx_lo = _mm_loadu_ps(x);
    __m128 vx_hi = _mm_loadu_ps(x + 4);
    x += 8;

    vx_lo = _mm_mul_ps(vx_lo, vscale);
    vx_hi = _mm_mul_ps(vx_hi, vscale);

    vx_lo = _mm_min_ps(vx_lo, voutput_max_less_zero_point);
    vx_hi = _mm_min_ps(vx_hi, voutput_max_less_zero_point);

    const __m128i vy_lo = _mm_cvtps_epi32(vx_lo);
    const __m128i vy_hi = _mm_cvtps_epi32(vx_hi);

    __m128i vy = _mm_packs_epi32(vy_lo, vy_hi);
    vy = _mm_adds_epi16(vy, voutput_zero_point);
    $if DATATYPE == "QS8" and SSE < 4:
      vy = _mm_max_epi16(vy, voutput_min);
    vy = ${_MM_PACKXS_EPI16}(vy, vy);
    $if DATATYPE == "QU8" or SSE == 4:
      vy = ${_MM_MAX_EPX8}(vy, voutput_min);

    _mm_storel_epi64((__m128i*) y, vy);
    y += 8;
  }
  if XNN_UNLIKELY(n != 0) {
    __m128 vx_lo = _mm_loadu_ps(x);
    const float* x_hi = (const float*) ((uintptr_t) x + (n & (4 * sizeof(float))));
    __m128 vx_hi = _mm_loadu_ps(x_hi);

    vx_lo = _mm_mul_ps(vx_lo, vscale);
    vx_hi = _mm_mul_ps(vx_hi, vscale);

    vx_lo = _mm_min_ps(vx_lo, voutput_max_less_zero_point);
    vx_hi = _mm_min_ps(vx_hi, voutput_max_less_zero_point);

    const __m128i vy_lo = _mm_cvtps_epi32(vx_lo);
    const __m128i vy_hi = _mm_cvtps_epi32(vx_hi);

    __m128i vy = _mm_packs_epi32(vy_lo, vy_hi);
    vy = _mm_adds_epi16(vy, voutput_zero_point);
    $if DATATYPE == "QS8" and SSE < 4:
      vy = _mm_max_epi16(vy, voutput_min);
    vy = ${_MM_PACKXS_EPI16}(vy, vy);
    $if DATATYPE == "QU8" or SSE == 4:
      vy = ${_MM_MAX_EPX8}(vy, voutput_min);

    if (n & (4 * sizeof(float))) {
      unaligned_store_u32(y, (uint32_t) _mm_cvtsi128_si32(vy));
      y += 4;
      vy = _mm_srli_epi64(vy, 32);
    }
    $if SSE == 4:
      if (n & (2 * sizeof(float))) {
        unaligned_store_u16(y, (uint16_t) _mm_extract_epi16(vy, 0));
        y += 2;
        vy = _mm_srli_epi32(vy, 16);
      }
      if (n & (1 * sizeof(float))) {
        *y = (${XINT8_T}) _mm_extract_epi8(vy, 0);
      }
    $else:
      {
        uint32_t vy_lo = (uint32_t) _mm_cvtsi128_si32(vy);
        if (n & (2 * sizeof(float))) {
          unaligned_store_u16(y, (uint16_t) vy_lo);
          y += 2;
          vy_lo >>= 16;
        }
        if (n & (1 * sizeof(float))) {
          *y = (${XINT8_T}) vy_lo;
        }
      }
  }
}