// Copyright 2022 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
$assert BATCH_TILE == 8 or BATCH_TILE % 16 == 0
$SIMD_TILE = BATCH_TILE // 16
$ABC = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#include <assert.h>

#include <wasm_simd128.h>

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


$XINT8_T = {"QS8": "int8_t", "QU8": "uint8_t"}[DATATYPE]
$WASM_X16X8_LOAD8X8 = {"QS8": "wasm_i16x8_load8x8", "QU8": "wasm_u16x8_load8x8"}[DATATYPE]
$WASM_I16X8_Q15MULR = "__builtin_wasm_relaxed_q15mulr_s_i16x8" if RELAXED else "wasm_i16x8_q15mulr_sat"
$WASM_X8X16_NARROW_I16X8 = {"QS8": "wasm_i8x16_narrow_i16x8", "QU8": "wasm_u8x16_narrow_i16x8"}[DATATYPE]
$ISA = "wasmrelaxedsimd" if RELAXED else "wasmsimd"
void xnn_${DATATYPE.lower()}_vcvt_ukernel__${ISA}_x${BATCH_TILE}(
    size_t n,
    const ${XINT8_T}* x,
    ${XINT8_T}* y,
    const union xnn_${DATATYPE.lower()}_cvt_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_OOB_READS
{
  assert(n != 0);
  assert(n % sizeof(${XINT8_T}) == 0);
  assert(x != NULL);
  assert(y != NULL);

  const v128_t vinput_zero_point = wasm_v128_load64_splat(params->wasmsimd.input_zero_point);
  const v128_t vmultiplier = wasm_v128_load64_splat(params->wasmsimd.multiplier);
  const v128_t voutput_zero_point = wasm_v128_load64_splat(params->wasmsimd.output_zero_point);
  $if BATCH_TILE > 8:
    for (; n >= ${BATCH_TILE} * sizeof(${XINT8_T}); n -= ${BATCH_TILE} * sizeof(${XINT8_T})) {
      v128_t vacc${ABC[0]} = ${WASM_X16X8_LOAD8X8}(x);
      $for N in range(1, 2*SIMD_TILE):
        v128_t vacc${ABC[N]} = ${WASM_X16X8_LOAD8X8}(x + ${N * 8});
      x += ${BATCH_TILE};

      $for N in range(2*SIMD_TILE):
        vacc${ABC[N]} = wasm_i16x8_sub(vinput_zero_point, vacc${ABC[N]});

      $for N in range(2*SIMD_TILE):
        vacc${ABC[N]} = wasm_i16x8_shl(vacc${ABC[N]}, 7);

      $for N in range(2*SIMD_TILE):
        vacc${ABC[N]} = ${WASM_I16X8_Q15MULR}(vacc${ABC[N]}, vmultiplier);

      $for N in range(2*SIMD_TILE):
        vacc${ABC[N]} = wasm_i16x8_add_sat(vacc${ABC[N]}, voutput_zero_point);

      $for N in range(SIMD_TILE):
        const v128_t vy${ABC[N]} = ${WASM_X8X16_NARROW_I16X8}(vacc${ABC[2*N]}, vacc${ABC[2*N+1]});

      wasm_v128_store(y, vy${ABC[0]});
      $for N in range(1, SIMD_TILE):
        wasm_v128_store((y + ${N * 16}), vy${ABC[N]});
      y += ${BATCH_TILE};
    }
  for (; n >= 8 * sizeof(${XINT8_T}); n -= 8 * sizeof(${XINT8_T})) {
    v128_t vacc = ${WASM_X16X8_LOAD8X8}(x);
    vacc = wasm_i16x8_sub(vinput_zero_point, vacc);
    vacc = wasm_i16x8_shl(vacc, 7);
    vacc = ${WASM_I16X8_Q15MULR}(vacc, vmultiplier);
    vacc = wasm_i16x8_add_sat(vacc, voutput_zero_point);
    x += 8;

    const v128_t vy = ${WASM_X8X16_NARROW_I16X8}(vacc, vacc);
    wasm_v128_store64_lane(y, vy, 0);
    y += 8;
  }
  if XNN_UNLIKELY(n != 0) {
    assert(n >= 1 * sizeof(${XINT8_T}));
    assert(n <= 7 * sizeof(${XINT8_T}));

    v128_t vacc = ${WASM_X16X8_LOAD8X8}(x);
    vacc = wasm_i16x8_sub(vinput_zero_point, vacc);
    vacc = wasm_i16x8_shl(vacc, 7);
    vacc = ${WASM_I16X8_Q15MULR}(vacc, vmultiplier);
    vacc = wasm_i16x8_add_sat(vacc, voutput_zero_point);

    v128_t vy = ${WASM_X8X16_NARROW_I16X8}(vacc, vacc);
    if (n & (4 * sizeof(${XINT8_T}))) {
      wasm_v128_store32_lane(y, vy, 0);
      vy = wasm_u64x2_shr(vy, 32);
      y += 4;
    }
    if (n & (2 * sizeof(${XINT8_T}))) {
      wasm_v128_store16_lane(y, vy, 0);
      vy = wasm_u32x4_shr(vy, 16);
      y += 2;
    }
    if (n & (1 * sizeof(${XINT8_T}))) {
      wasm_v128_store8_lane(y, vy, 0);
    }
  }
}