1 /*
2  *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include <arm_neon.h>
12 #include "./vp9_rtcd.h"
13 #include "./vpx_config.h"
14 
15 #include "vpx/vpx_integer.h"
16 
vp9_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)17 void vp9_subtract_block_neon(int rows, int cols,
18                              int16_t *diff, ptrdiff_t diff_stride,
19                              const uint8_t *src, ptrdiff_t src_stride,
20                              const uint8_t *pred, ptrdiff_t pred_stride) {
21   int r, c;
22 
23   if (cols > 16) {
24     for (r = 0; r < rows; ++r) {
25       for (c = 0; c < cols; c += 32) {
26         const uint8x16_t v_src_00 = vld1q_u8(&src[c + 0]);
27         const uint8x16_t v_src_16 = vld1q_u8(&src[c + 16]);
28         const uint8x16_t v_pred_00 = vld1q_u8(&pred[c +  0]);
29         const uint8x16_t v_pred_16 = vld1q_u8(&pred[c + 16]);
30         const uint16x8_t v_diff_lo_00 = vsubl_u8(vget_low_u8(v_src_00),
31                                                  vget_low_u8(v_pred_00));
32         const uint16x8_t v_diff_hi_00 = vsubl_u8(vget_high_u8(v_src_00),
33                                                  vget_high_u8(v_pred_00));
34         const uint16x8_t v_diff_lo_16 = vsubl_u8(vget_low_u8(v_src_16),
35                                                  vget_low_u8(v_pred_16));
36         const uint16x8_t v_diff_hi_16 = vsubl_u8(vget_high_u8(v_src_16),
37                                                  vget_high_u8(v_pred_16));
38         vst1q_s16(&diff[c +  0], vreinterpretq_s16_u16(v_diff_lo_00));
39         vst1q_s16(&diff[c +  8], vreinterpretq_s16_u16(v_diff_hi_00));
40         vst1q_s16(&diff[c + 16], vreinterpretq_s16_u16(v_diff_lo_16));
41         vst1q_s16(&diff[c + 24], vreinterpretq_s16_u16(v_diff_hi_16));
42       }
43       diff += diff_stride;
44       pred += pred_stride;
45       src  += src_stride;
46     }
47   } else if (cols > 8) {
48     for (r = 0; r < rows; ++r) {
49       const uint8x16_t v_src = vld1q_u8(&src[0]);
50       const uint8x16_t v_pred = vld1q_u8(&pred[0]);
51       const uint16x8_t v_diff_lo = vsubl_u8(vget_low_u8(v_src),
52                                             vget_low_u8(v_pred));
53       const uint16x8_t v_diff_hi = vsubl_u8(vget_high_u8(v_src),
54                                             vget_high_u8(v_pred));
55       vst1q_s16(&diff[0], vreinterpretq_s16_u16(v_diff_lo));
56       vst1q_s16(&diff[8], vreinterpretq_s16_u16(v_diff_hi));
57       diff += diff_stride;
58       pred += pred_stride;
59       src  += src_stride;
60     }
61   } else if (cols > 4) {
62     for (r = 0; r < rows; ++r) {
63       const uint8x8_t v_src = vld1_u8(&src[0]);
64       const uint8x8_t v_pred = vld1_u8(&pred[0]);
65       const uint16x8_t v_diff = vsubl_u8(v_src, v_pred);
66       vst1q_s16(&diff[0], vreinterpretq_s16_u16(v_diff));
67       diff += diff_stride;
68       pred += pred_stride;
69       src  += src_stride;
70     }
71   } else {
72     for (r = 0; r < rows; ++r) {
73       for (c = 0; c < cols; ++c)
74         diff[c] = src[c] - pred[c];
75 
76       diff += diff_stride;
77       pred += pred_stride;
78       src  += src_stride;
79     }
80   }
81 }
82