ref: d757d7e998d2e247a6fea424e8cb67e5f2b17951
dir: /vpx_dsp/arm/idct4x4_1_add_neon.c/
/*
* Copyright (c) 2014 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <arm_neon.h>
#include <assert.h>
#include "./vpx_dsp_rtcd.h"
#include "vpx_dsp/inv_txfm.h"
void vpx_idct4x4_1_add_neon(const tran_low_t *input, uint8_t *dest,
int dest_stride) {
int i;
const int16_t out0 = dct_const_round_shift((int16_t)input[0] * cospi_16_64);
const int16_t out1 = dct_const_round_shift(out0 * cospi_16_64);
const int16_t a1 = ROUND_POWER_OF_TWO(out1, 4);
const int16x8_t dc = vdupq_n_s16(a1);
uint32x2_t d = vdup_n_u32(0);
uint16x8_t a;
uint8x8_t b;
assert(!((intptr_t)dest % sizeof(uint32_t)));
assert(!(dest_stride % sizeof(uint32_t)));
for (i = 0; i < 2; i++) {
d = vld1_lane_u32((const uint32_t *)dest, d, 0);
d = vld1_lane_u32((const uint32_t *)(dest + dest_stride), d, 1);
a = vaddw_u8(vreinterpretq_u16_s16(dc), vreinterpret_u8_u32(d));
b = vqmovun_s16(vreinterpretq_s16_u16(a));
vst1_lane_u32((uint32_t *)dest, vreinterpret_u32_u8(b), 0);
dest += dest_stride;
vst1_lane_u32((uint32_t *)dest, vreinterpret_u32_u8(b), 1);
dest += dest_stride;
}
}