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Diffstat (limited to 'src/vppinfra/xxhash.h')
| -rw-r--r-- | src/vppinfra/xxhash.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/src/vppinfra/xxhash.h b/src/vppinfra/xxhash.h new file mode 100644 index 00000000..ea1e21bf --- /dev/null +++ b/src/vppinfra/xxhash.h @@ -0,0 +1,86 @@ +/* + * 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. + */ +/* + Original license for the code used to construct + clib_xxhash(...). + + xxHash - Fast Hash algorithm + Copyright (C) 2012-2014, Yann Collet. + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +#ifndef __included_xxhash_h__ +#define __included_xxhash_h__ + +#define PRIME64_1 11400714785074694791ULL +#define PRIME64_2 14029467366897019727ULL +#define PRIME64_3 1609587929392839161ULL +#define PRIME64_4 9650029242287828579ULL +#define PRIME64_5 2870177450012600261ULL +#define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r))) + +static inline u64 +clib_xxhash (u64 key) +{ + u64 k1, h64; + + k1 = key; + h64 = 0x9e3779b97f4a7c13LL + PRIME64_5 + 8; + k1 *= PRIME64_2; + k1 = XXH_rotl64 (k1, 31); + k1 *= PRIME64_1; + h64 ^= k1; + h64 = XXH_rotl64 (h64, 27) * PRIME64_1 + PRIME64_4; + + h64 ^= h64 >> 33; + h64 *= PRIME64_2; + h64 ^= h64 >> 29; + h64 *= PRIME64_3; + h64 ^= h64 >> 32; + return h64; +} + +#endif /* __included_xxhash_h__ */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |