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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
16 #ifndef __included_crc32_h__
17 #define __included_crc32_h__
20 #define clib_crc32c_uses_intrinsics
21 #include <x86intrin.h>
23 static_always_inline u32
24 clib_crc32c (u8 * s, int len)
29 for (; len >= 8; len -= 8, s += 8)
30 v = _mm_crc32_u64 (v, *((u64 *) s));
32 /* workaround weird GCC bug when using _mm_crc32_u32
33 which happens with -O2 optimization */
34 volatile ("":::"memory");
37 for (; len >= 4; len -= 4, s += 4)
38 v = _mm_crc32_u32 (v, *((u32 *) s));
40 for (; len >= 2; len -= 2, s += 2)
41 v = _mm_crc32_u16 (v, *((u16 *) s));
43 for (; len >= 1; len -= 1, s += 1)
44 v = _mm_crc32_u8 (v, *((u16 *) s));
49 #elif __ARM_FEATURE_CRC32
50 #define clib_crc32c_with_intrinsics
53 static_always_inline u32
54 clib_crc32c (u8 * s, int len)
58 for (; len >= 8; len -= 8, s += 8)
59 v = __crc32cd (v, *((u64 *) s));
61 for (; len >= 4; len -= 4, s += 4)
62 v = __crc32cw (v, *((u32 *) s));
64 for (; len >= 2; len -= 2, s += 2)
65 v = __crc32ch (v, *((u16 *) s));
67 for (; len >= 1; len -= 1, s += 1)
68 v = __crc32cb (v, *((u8 *) s));
74 #endif /* __included_crc32_h__ */
77 * fd.io coding-style-patch-verification: ON
80 * eval: (c-set-style "gnu")