// 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 BATCH_TILE % 8 == 0
$assert BATCH_TILE >= 8
$ABC = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#include <assert.h>

#include <arm_neon.h>

#include "xnnpack/common.h"
#include "xnnpack/intrinsics-polyfill.h"
#include "xnnpack/vcvt.h"


$XINT8_T = {"QS8": "int8_t", "QU8": "uint8_t"}[DATATYPE]
$XINT8X8_T = {"QS8": "int8x8_t", "QU8": "uint8x8_t"}[DATATYPE]
$VLD1_X8 = {"QS8": "vld1_s8", "QU8": "vld1_u8"}[DATATYPE]
$VLD1_X16 = {"QS8": "vld1_s16", "QU8": "vld1_u16"}[DATATYPE]
void xnn_${DATATYPE.lower()}_f32_vcvt_ukernel__neon_u${BATCH_TILE}(
    size_t batch,
    const ${XINT8_T}* input,
    float* output,
    const struct xnn_${DATATYPE.lower()}_f32_cvt_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_OOB_READS
{
  assert(batch != 0);
  assert(batch % sizeof(${XINT8_T}) == 0);
  assert(input != NULL);
  assert(output != NULL);

  const int16x8_t vminus_zero_point = vdupq_n_s16(-params->scalar.zero_point);
  const float32x4_t vscale = vld1q_dup_f32(&params->scalar.scale);
  $if BATCH_TILE > 8:
    for (; batch >= ${BATCH_TILE} * sizeof(${XINT8_T}); batch -= ${BATCH_TILE} * sizeof(${XINT8_T})) {
      $for N in range(0, BATCH_TILE, 8):
        const ${XINT8X8_T} vx${ABC[N:N+8]} = ${VLD1_X8}(input); input += 8;

      $for N in range(0, BATCH_TILE, 8):
        $if DATATYPE == "QU8":
          const int16x8_t vhx${ABC[N:N+8]} = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(vminus_zero_point), vx${ABC[N:N+8]}));
        $else:
          const int16x8_t vhx${ABC[N:N+8]} = vaddw_s8(vminus_zero_point, vx${ABC[N:N+8]});

      $for N in range(0, BATCH_TILE, 8):
        const int32x4_t vwx${ABC[N:N+4]} = vmovl_s16(vget_low_s16(vhx${ABC[N:N+8]}));
        const int32x4_t vwx${ABC[N+4:N+8]} = vmovl_s16(vget_high_s16(vhx${ABC[N:N+8]}));

      $for N in range(0, BATCH_TILE, 4):
        float32x4_t vy${ABC[N:N+4]} = vcvtq_f32_s32(vwx${ABC[N:N+4]});

      $for N in range(0, BATCH_TILE, 4):
        vy${ABC[N:N+4]} = vmulq_f32(vy${ABC[N:N+4]}, vscale);

      $for N in range(0, BATCH_TILE, 4):
        vst1q_f32(output, vy${ABC[N:N+4]}); output += 4;
    }
  for (; batch >= 8 * sizeof(${XINT8_T}); batch -= 8 * sizeof(${XINT8_T})) {
    const ${XINT8X8_T} vx = ${VLD1_X8}(input); input += 8;

    $if DATATYPE == "QU8":
      const int16x8_t vhx = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(vminus_zero_point), vx));
    $else:
      const int16x8_t vhx = vaddw_s8(vminus_zero_point, vx);

    const int32x4_t vwx_lo = vmovl_s16(vget_low_s16(vhx));
    const int32x4_t vwx_hi = vmovl_s16(vget_high_s16(vhx));

    float32x4_t vy_lo = vcvtq_f32_s32(vwx_lo);
    float32x4_t vy_hi = vcvtq_f32_s32(vwx_hi);

    vy_lo = vmulq_f32(vy_lo, vscale);
    vy_hi = vmulq_f32(vy_hi, vscale);

    vst1q_f32(output, vy_lo); output += 4;
    vst1q_f32(output, vy_hi); output += 4;
  }
  if XNN_UNLIKELY(batch != 0) {
    assert(batch >= 1 * sizeof(${XINT8_T}));
    assert(batch <= 7 * sizeof(${XINT8_T}));

    const ${XINT8X8_T} vx = ${VLD1_X8}(input);

    $if DATATYPE == "QU8":
      const int16x8_t vhx = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(vminus_zero_point), vx));
    $else:
      const int16x8_t vhx = vaddw_s8(vminus_zero_point, vx);

    const int32x4_t vwx_lo = vmovl_s16(vget_low_s16(vhx));
    const int32x4_t vwx_hi = vmovl_s16(vget_high_s16(vhx));

    float32x4_t vy = vcvtq_f32_s32(vwx_lo);
    vy = vmulq_f32(vy, vscale);

    if (batch & (4 * sizeof(${XINT8_T}))) {
      vst1q_f32(output, vy); output += 4;
      vy = vcvtq_f32_s32(vwx_hi);
      vy = vmulq_f32(vy, vscale);
    }
    float32x2_t vy_lo = vget_low_f32(vy);
    if (batch & (2 * sizeof(${XINT8_T}))) {
      vst1_f32(output, vy_lo); output += 2;
      vy_lo = vget_high_f32(vy);
    }
    if (batch & (1 * sizeof(${XINT8_T}))) {
      vst1_lane_f32(output, vy_lo, 0);
    }
  }
}
