ref: f1fc47becf4381fcb1679b69dfc2501eb381e9cb
dir: /vpx_dsp/arm/subtract_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 "./vpx_config.h"
#include "vpx/vpx_integer.h"
void vpx_subtract_block_neon(int rows, int cols,
int16_t *diff, ptrdiff_t diff_stride,
const uint8_t *src, ptrdiff_t src_stride,
const uint8_t *pred, ptrdiff_t pred_stride) {
int r, c;
if (cols > 16) {
for (r = 0; r < rows; ++r) {
for (c = 0; c < cols; c += 32) {
const uint8x16_t v_src_00 = vld1q_u8(&src[c + 0]);
const uint8x16_t v_src_16 = vld1q_u8(&src[c + 16]);
const uint8x16_t v_pred_00 = vld1q_u8(&pred[c + 0]);
const uint8x16_t v_pred_16 = vld1q_u8(&pred[c + 16]);
const uint16x8_t v_diff_lo_00 = vsubl_u8(vget_low_u8(v_src_00),
vget_low_u8(v_pred_00));
const uint16x8_t v_diff_hi_00 = vsubl_u8(vget_high_u8(v_src_00),
vget_high_u8(v_pred_00));
const uint16x8_t v_diff_lo_16 = vsubl_u8(vget_low_u8(v_src_16),
vget_low_u8(v_pred_16));
const uint16x8_t v_diff_hi_16 = vsubl_u8(vget_high_u8(v_src_16),
vget_high_u8(v_pred_16));
vst1q_s16(&diff[c + 0], vreinterpretq_s16_u16(v_diff_lo_00));
vst1q_s16(&diff[c + 8], vreinterpretq_s16_u16(v_diff_hi_00));
vst1q_s16(&diff[c + 16], vreinterpretq_s16_u16(v_diff_lo_16));
vst1q_s16(&diff[c + 24], vreinterpretq_s16_u16(v_diff_hi_16));
}
diff += diff_stride;
pred += pred_stride;
src += src_stride;
}
} else if (cols > 8) {
for (r = 0; r < rows; ++r) {
const uint8x16_t v_src = vld1q_u8(&src[0]);
const uint8x16_t v_pred = vld1q_u8(&pred[0]);
const uint16x8_t v_diff_lo = vsubl_u8(vget_low_u8(v_src),
vget_low_u8(v_pred));
const uint16x8_t v_diff_hi = vsubl_u8(vget_high_u8(v_src),
vget_high_u8(v_pred));
vst1q_s16(&diff[0], vreinterpretq_s16_u16(v_diff_lo));
vst1q_s16(&diff[8], vreinterpretq_s16_u16(v_diff_hi));
diff += diff_stride;
pred += pred_stride;
src += src_stride;
}
} else if (cols > 4) {
for (r = 0; r < rows; ++r) {
const uint8x8_t v_src = vld1_u8(&src[0]);
const uint8x8_t v_pred = vld1_u8(&pred[0]);
const uint16x8_t v_diff = vsubl_u8(v_src, v_pred);
vst1q_s16(&diff[0], vreinterpretq_s16_u16(v_diff));
diff += diff_stride;
pred += pred_stride;
src += src_stride;
}
} else {
for (r = 0; r < rows; ++r) {
for (c = 0; c < cols; ++c)
diff[c] = src[c] - pred[c];
diff += diff_stride;
pred += pred_stride;
src += src_stride;
}
}
}