FD.io VPP  v20.01-48-g3e0dafb74
Vector Packet Processing
crc32.h
Go to the documentation of this file.
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 defined(__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 #if !defined (__i686__)
40  asm volatile ("":::"memory");
41 #endif
42 #endif
43 
44  for (; len >= 4; len -= 4, s += 4)
45  v = _mm_crc32_u32 (v, *((u32 *) s));
46 
47  for (; len >= 2; len -= 2, s += 2)
48  v = _mm_crc32_u16 (v, *((u16 *) s));
49 
50  for (; len >= 1; len -= 1, s += 1)
51  v = _mm_crc32_u8 (v, *((u16 *) s));
52 
53  return v;
54 }
55 
56 #elif __ARM_FEATURE_CRC32
57 #define clib_crc32c_uses_intrinsics
58 #include <arm_acle.h>
59 
60 
61 #define crc32_u64 __crc32cd
62 #define crc32_u32 __crc32cw
63 
65 clib_crc32c (u8 * s, int len)
66 {
67  u32 v = 0;
68 
69  for (; len >= 8; len -= 8, s += 8)
70  v = __crc32cd (v, *((u64 *) s));
71 
72  for (; len >= 4; len -= 4, s += 4)
73  v = __crc32cw (v, *((u32 *) s));
74 
75  for (; len >= 2; len -= 2, s += 2)
76  v = __crc32ch (v, *((u16 *) s));
77 
78  for (; len >= 1; len -= 1, s += 1)
79  v = __crc32cb (v, *((u8 *) s));
80 
81  return v;
82 }
83 
84 #endif
85 #endif /* __included_crc32_h__ */
86 
87 /*
88  * fd.io coding-style-patch-verification: ON
89  *
90  * Local Variables:
91  * eval: (c-set-style "gnu")
92  * End:
93  */
unsigned long u64
Definition: types.h:89
unsigned char u8
Definition: types.h:56
#define static_always_inline
Definition: clib.h:99
unsigned int u32
Definition: types.h:88
unsigned short u16
Definition: types.h:57