diff options
Diffstat (limited to 'src/vppinfra/crc32.h')
-rw-r--r-- | src/vppinfra/crc32.h | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/vppinfra/crc32.h b/src/vppinfra/crc32.h new file mode 100644 index 00000000000..abb2953fb4d --- /dev/null +++ b/src/vppinfra/crc32.h @@ -0,0 +1,58 @@ +/* + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef __included_crc32_h__ +#define __included_crc32_h__ + +#if __SSE4_2__ +#include <x86intrin.h> + +static_always_inline u32 +clib_crc32c (u8 * s, int len) +{ + u32 v = 0; + +#if __x86_64__ + for (; len >= 8; len -= 8, s += 8) + v = _mm_crc32_u64 (v, *((u64 *) s)); +#else + /* workaround weird GCC bug when using _mm_crc32_u32 + which happens with -O2 optimization */ + volatile ("":::"memory"); +#endif + + for (; len >= 4; len -= 4, s += 4) + v = _mm_crc32_u32 (v, *((u32 *) s)); + + for (; len >= 2; len -= 2, s += 2) + v = _mm_crc32_u16 (v, *((u16 *) s)); + + for (; len >= 1; len -= 1, s += 1) + v = _mm_crc32_u8 (v, *((u16 *) s)); + + return v; +} + +#endif + +#endif /* __included_crc32_h__ */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |