1 /*
2  *  Copyright 2012 The LibYuv 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 "libyuv/basic_types.h"
12 
13 #include "libyuv/compare_row.h"
14 #include "libyuv/row.h"
15 
16 #ifdef __cplusplus
17 namespace libyuv {
18 extern "C" {
19 #endif
20 
21 #if !defined(LIBYUV_DISABLE_NEON) && defined(__ARM_NEON__) && \
22     !defined(__aarch64__)
23 
24 // 256 bits at a time
25 // uses short accumulator which restricts count to 131 KB
HammingDistance_NEON(const uint8_t * src_a,const uint8_t * src_b,int count)26 uint32_t HammingDistance_NEON(const uint8_t* src_a,
27                               const uint8_t* src_b,
28                               int count) {
29   uint32_t diff;
30 
31   asm volatile(
32       "vmov.u16    q4, #0                        \n"  // accumulator
33 
34       "1:                                        \n"
35       "vld1.8      {q0, q1}, [%0]!               \n"
36       "vld1.8      {q2, q3}, [%1]!               \n"
37       "veor.32     q0, q0, q2                    \n"
38       "veor.32     q1, q1, q3                    \n"
39       "vcnt.i8     q0, q0                        \n"
40       "vcnt.i8     q1, q1                        \n"
41       "subs        %2, %2, #32                   \n"
42       "vadd.u8     q0, q0, q1                    \n"  // 16 byte counts
43       "vpadal.u8   q4, q0                        \n"  // 8 shorts
44       "bgt         1b                            \n"
45 
46       "vpaddl.u16  q0, q4                        \n"  // 4 ints
47       "vpadd.u32   d0, d0, d1                    \n"
48       "vpadd.u32   d0, d0, d0                    \n"
49       "vmov.32     %3, d0[0]                     \n"
50 
51       : "+r"(src_a), "+r"(src_b), "+r"(count), "=r"(diff)
52       :
53       : "cc", "q0", "q1", "q2", "q3", "q4");
54   return diff;
55 }
56 
SumSquareError_NEON(const uint8_t * src_a,const uint8_t * src_b,int count)57 uint32_t SumSquareError_NEON(const uint8_t* src_a,
58                              const uint8_t* src_b,
59                              int count) {
60   uint32_t sse;
61   asm volatile(
62       "vmov.u8     q8, #0                        \n"
63       "vmov.u8     q10, #0                       \n"
64       "vmov.u8     q9, #0                        \n"
65       "vmov.u8     q11, #0                       \n"
66 
67       "1:                                        \n"
68       "vld1.8      {q0}, [%0]!                   \n"
69       "vld1.8      {q1}, [%1]!                   \n"
70       "subs        %2, %2, #16                   \n"
71       "vsubl.u8    q2, d0, d2                    \n"
72       "vsubl.u8    q3, d1, d3                    \n"
73       "vmlal.s16   q8, d4, d4                    \n"
74       "vmlal.s16   q9, d6, d6                    \n"
75       "vmlal.s16   q10, d5, d5                   \n"
76       "vmlal.s16   q11, d7, d7                   \n"
77       "bgt         1b                            \n"
78 
79       "vadd.u32    q8, q8, q9                    \n"
80       "vadd.u32    q10, q10, q11                 \n"
81       "vadd.u32    q11, q8, q10                  \n"
82       "vpaddl.u32  q1, q11                       \n"
83       "vadd.u64    d0, d2, d3                    \n"
84       "vmov.32     %3, d0[0]                     \n"
85       : "+r"(src_a), "+r"(src_b), "+r"(count), "=r"(sse)
86       :
87       : "memory", "cc", "q0", "q1", "q2", "q3", "q8", "q9", "q10", "q11");
88   return sse;
89 }
90 
91 #endif  // defined(__ARM_NEON__) && !defined(__aarch64__)
92 
93 #ifdef __cplusplus
94 }  // extern "C"
95 }  // namespace libyuv
96 #endif
97