FD.io VPP  v18.01.2-1-g9b554f3
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 
28 clib_crc32c (u8 * s, int len)
29 {
30  u32 v = 0;
31 
32 #if __x86_64__
33  for (; len >= 8; len -= 8, s += 8)
34  v = _mm_crc32_u64 (v, *((u64 *) s));
35 #else
36  /* workaround weird GCC bug when using _mm_crc32_u32
37  which happens with -O2 optimization */
38  volatile ("":::"memory");
39 #endif
40 
41  for (; len >= 4; len -= 4, s += 4)
42  v = _mm_crc32_u32 (v, *((u32 *) s));
43 
44  for (; len >= 2; len -= 2, s += 2)
45  v = _mm_crc32_u16 (v, *((u16 *) s));
46 
47  for (; len >= 1; len -= 1, s += 1)
48  v = _mm_crc32_u8 (v, *((u16 *) s));
49 
50  return v;
51 }
52 
53 #elif __ARM_FEATURE_CRC32
54 #define clib_crc32c_uses_intrinsics
55 #include <arm_acle.h>
56 
57 
58 #define crc32_u64 __crc32cd
59 
61 clib_crc32c (u8 * s, int len)
62 {
63  u32 v = 0;
64 
65  for (; len >= 8; len -= 8, s += 8)
66  v = __crc32cd (v, *((u64 *) s));
67 
68  for (; len >= 4; len -= 4, s += 4)
69  v = __crc32cw (v, *((u32 *) s));
70 
71  for (; len >= 2; len -= 2, s += 2)
72  v = __crc32ch (v, *((u16 *) s));
73 
74  for (; len >= 1; len -= 1, s += 1)
75  v = __crc32cb (v, *((u8 *) s));
76 
77  return v;
78 }
79 
80 #endif
81 #endif /* __included_crc32_h__ */
82 
83 /*
84  * fd.io coding-style-patch-verification: ON
85  *
86  * Local Variables:
87  * eval: (c-set-style "gnu")
88  * End:
89  */
#define static_always_inline
Definition: clib.h:93
unsigned long u64
Definition: types.h:89
#define v
Definition: acl.c:341
unsigned int u32
Definition: types.h:88
unsigned short u16
Definition: types.h:57
unsigned char u8
Definition: types.h:56