FD.io VPP  v18.04-17-g3a0d853
Vector Packet Processing
crc32.h
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1 /*
2  * Copyright (c) 2015 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef __included_crc32_h__
17 #define __included_crc32_h__
18 
19 #include <vppinfra/clib.h>
20 
21 #if __SSE4_2__
22 #define clib_crc32c_uses_intrinsics
23 #include <x86intrin.h>
24 
25 #define crc32_u64 _mm_crc32_u64
26 #define crc32_u32 _mm_crc32_u32
27 
29 clib_crc32c (u8 * s, int len)
30 {
31  u32 v = 0;
32 
33 #if __x86_64__
34  for (; len >= 8; len -= 8, s += 8)
35  v = _mm_crc32_u64 (v, *((u64 *) s));
36 #else
37  /* workaround weird GCC bug when using _mm_crc32_u32
38  which happens with -O2 optimization */
39  volatile ("":::"memory");
40 #endif
41 
42  for (; len >= 4; len -= 4, s += 4)
43  v = _mm_crc32_u32 (v, *((u32 *) s));
44 
45  for (; len >= 2; len -= 2, s += 2)
46  v = _mm_crc32_u16 (v, *((u16 *) s));
47 
48  for (; len >= 1; len -= 1, s += 1)
49  v = _mm_crc32_u8 (v, *((u16 *) s));
50 
51  return v;
52 }
53 
54 #elif __ARM_FEATURE_CRC32
55 #define clib_crc32c_uses_intrinsics
56 #include <arm_acle.h>
57 
58 
59 #define crc32_u64 __crc32cd
60 #define crc32_u32 __crc32cw
61 
63 clib_crc32c (u8 * s, int len)
64 {
65  u32 v = 0;
66 
67  for (; len >= 8; len -= 8, s += 8)
68  v = __crc32cd (v, *((u64 *) s));
69 
70  for (; len >= 4; len -= 4, s += 4)
71  v = __crc32cw (v, *((u32 *) s));
72 
73  for (; len >= 2; len -= 2, s += 2)
74  v = __crc32ch (v, *((u16 *) s));
75 
76  for (; len >= 1; len -= 1, s += 1)
77  v = __crc32cb (v, *((u8 *) s));
78 
79  return v;
80 }
81 
82 #endif
83 #endif /* __included_crc32_h__ */
84 
85 /*
86  * fd.io coding-style-patch-verification: ON
87  *
88  * Local Variables:
89  * eval: (c-set-style "gnu")
90  * End:
91  */
#define static_always_inline
Definition: clib.h:93
unsigned long u64
Definition: types.h:89
#define v
Definition: acl.c:495
unsigned int u32
Definition: types.h:88
unsigned short u16
Definition: types.h:57
unsigned char u8
Definition: types.h:56