src/f32-qs8-vcvt/avx.c.in

// 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 DATATYPE in ["QS8", "QU8"]
$assert BATCH_TILE % 8 == 0
$assert BATCH_TILE >= 8
$ABC = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#include <assert.h>

#include <immintrin.h>

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


$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__avx_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 __m256 vscale = _mm256_load_ps(params->avx.scale);
  const __m256 voutput_max_less_zero_point = _mm256_load_ps(params->avx.output_max_less_zero_point);
  const __m128i voutput_zero_point = _mm_load_si128((const __m128i*) params->avx.output_zero_point);
  const __m128i voutput_min = _mm_load_si128((const __m128i*) params->avx.output_min);

  $if BATCH_TILE > 8:
    for (; n >= ${BATCH_TILE} * sizeof(float); n -= ${BATCH_TILE} * sizeof(float)) {
      __m256 vx${ABC[0:8]} = _mm256_loadu_ps(x);
      $for N in range(8, BATCH_TILE, 8):
        __m256 vx${ABC[N:N+8]} = _mm256_loadu_ps(x + ${N});
      x += ${BATCH_TILE};

      $for N in range(0, BATCH_TILE, 8):
        vx${ABC[N:N+8]} = _mm256_mul_ps(vx${ABC[N:N+8]}, vscale);

      $for N in range(0, BATCH_TILE, 8):
        vx${ABC[N:N+8]} = _mm256_min_ps(vx${ABC[N:N+8]}, voutput_max_less_zero_point);

      $for N in range(0, BATCH_TILE, 8):
        const __m256i vacc${ABC[N:N+8]} = _mm256_cvtps_epi32(vx${ABC[N:N+8]});

      $for N in range(0, BATCH_TILE, 8):
        __m128i vy${ABC[N:N+8]} = _mm_packs_epi32(_mm256_castsi256_si128(vacc${ABC[N:N+8]}), _mm256_extractf128_si256(vacc${ABC[N:N+8]}, 1));

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

      $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]});

      $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)) {
    __m256 vx = _mm256_loadu_ps(x);
    vx = _mm256_mul_ps(vx, vscale);
    vx = _mm256_min_ps(vx, voutput_max_less_zero_point);
    x += 8;

    const __m256i vacc = _mm256_cvtps_epi32(vx);

    __m128i vy = _mm_packs_epi32(_mm256_castsi256_si128(vacc), _mm256_extractf128_si256(vacc, 1));
    vy = _mm_adds_epi16(vy, voutput_zero_point);
    vy = ${_MM_PACKXS_EPI16}(vy, vy);
    vy = ${_MM_MAX_EPX8}(vy, voutput_min);

    _mm_storel_epi64((__m128i*) y, vy);
    y += 8;
  }
  if XNN_UNLIKELY(n != 0) {
    assert(n >= 1 * sizeof(float));
    assert(n <= 7 * sizeof(float));
    __m256i vmask = _mm256_loadu_si256((const __m256i*) ((uintptr_t) &params->avx.mask_table[7] - n));

    __m256 vx = _mm256_maskload_ps(x, vmask);
    vx = _mm256_mul_ps(vx, vscale);
    vx = _mm256_min_ps(vx, voutput_max_less_zero_point);

    const __m256i vacc = _mm256_cvtps_epi32(vx);

    __m128i vy = _mm_packs_epi32(_mm256_castsi256_si128(vacc), _mm256_extractf128_si256(vacc, 1));
    vy = _mm_adds_epi16(vy, voutput_zero_point);
    vy = ${_MM_PACKXS_EPI16}(vy, vy);
    vy = ${_MM_MAX_EPX8}(vy, voutput_min);

    if (n & (4 * sizeof(float))) {
      *((uint32_t*) y) = (uint32_t) _mm_cvtsi128_si32(vy);
      y += 4;
      vy = _mm_srli_epi64(vy, 32);
    }
    if (n & (2 * sizeof(float))) {
      *((uint16_t*) 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);
    }
  }
}