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freebsd
GitHub Repository: freebsd/freebsd-src
Path: blob/main/sys/contrib/zstd/lib/common/xxhash.h
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/*
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* xxHash - Fast Hash algorithm
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* Copyright (c) Yann Collet, Facebook, Inc.
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*
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* You can contact the author at :
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* - xxHash homepage: http://www.xxhash.com
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* - xxHash source repository : https://github.com/Cyan4973/xxHash
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*
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* This source code is licensed under both the BSD-style license (found in the
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* LICENSE file in the root directory of this source tree) and the GPLv2 (found
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* in the COPYING file in the root directory of this source tree).
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* You may select, at your option, one of the above-listed licenses.
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*/
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#ifndef XXH_NO_XXH3
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# define XXH_NO_XXH3
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#endif
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#ifndef XXH_NAMESPACE
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# define XXH_NAMESPACE ZSTD_
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#endif
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/*!
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* @mainpage xxHash
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*
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* @file xxhash.h
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* xxHash prototypes and implementation
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*/
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/* TODO: update */
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/* Notice extracted from xxHash homepage:
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xxHash is an extremely fast hash algorithm, running at RAM speed limits.
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It also successfully passes all tests from the SMHasher suite.
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Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
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Name Speed Q.Score Author
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xxHash 5.4 GB/s 10
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CrapWow 3.2 GB/s 2 Andrew
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MurmurHash 3a 2.7 GB/s 10 Austin Appleby
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SpookyHash 2.0 GB/s 10 Bob Jenkins
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SBox 1.4 GB/s 9 Bret Mulvey
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Lookup3 1.2 GB/s 9 Bob Jenkins
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SuperFastHash 1.2 GB/s 1 Paul Hsieh
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CityHash64 1.05 GB/s 10 Pike & Alakuijala
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FNV 0.55 GB/s 5 Fowler, Noll, Vo
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CRC32 0.43 GB/s 9
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MD5-32 0.33 GB/s 10 Ronald L. Rivest
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SHA1-32 0.28 GB/s 10
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Q.Score is a measure of quality of the hash function.
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It depends on successfully passing SMHasher test set.
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10 is a perfect score.
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Note: SMHasher's CRC32 implementation is not the fastest one.
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Other speed-oriented implementations can be faster,
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especially in combination with PCLMUL instruction:
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https://fastcompression.blogspot.com/2019/03/presenting-xxh3.html?showComment=1552696407071#c3490092340461170735
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A 64-bit version, named XXH64, is available since r35.
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It offers much better speed, but for 64-bit applications only.
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Name Speed on 64 bits Speed on 32 bits
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XXH64 13.8 GB/s 1.9 GB/s
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XXH32 6.8 GB/s 6.0 GB/s
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*/
67
68
#if defined (__cplusplus)
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extern "C" {
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#endif
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/* ****************************
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* INLINE mode
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******************************/
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/*!
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* XXH_INLINE_ALL (and XXH_PRIVATE_API)
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* Use these build macros to inline xxhash into the target unit.
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* Inlining improves performance on small inputs, especially when the length is
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* expressed as a compile-time constant:
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*
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* https://fastcompression.blogspot.com/2018/03/xxhash-for-small-keys-impressive-power.html
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*
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* It also keeps xxHash symbols private to the unit, so they are not exported.
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*
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* Usage:
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* #define XXH_INLINE_ALL
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* #include "xxhash.h"
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*
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* Do not compile and link xxhash.o as a separate object, as it is not useful.
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*/
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#if (defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)) \
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&& !defined(XXH_INLINE_ALL_31684351384)
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/* this section should be traversed only once */
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# define XXH_INLINE_ALL_31684351384
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/* give access to the advanced API, required to compile implementations */
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# undef XXH_STATIC_LINKING_ONLY /* avoid macro redef */
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# define XXH_STATIC_LINKING_ONLY
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/* make all functions private */
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# undef XXH_PUBLIC_API
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# if defined(__GNUC__)
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# define XXH_PUBLIC_API static __inline __attribute__((unused))
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# elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
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# define XXH_PUBLIC_API static inline
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# elif defined(_MSC_VER)
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# define XXH_PUBLIC_API static __inline
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# else
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/* note: this version may generate warnings for unused static functions */
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# define XXH_PUBLIC_API static
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# endif
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/*
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* This part deals with the special case where a unit wants to inline xxHash,
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* but "xxhash.h" has previously been included without XXH_INLINE_ALL,
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* such as part of some previously included *.h header file.
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* Without further action, the new include would just be ignored,
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* and functions would effectively _not_ be inlined (silent failure).
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* The following macros solve this situation by prefixing all inlined names,
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* avoiding naming collision with previous inclusions.
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*/
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/* Before that, we unconditionally #undef all symbols,
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* in case they were already defined with XXH_NAMESPACE.
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* They will then be redefined for XXH_INLINE_ALL
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*/
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# undef XXH_versionNumber
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/* XXH32 */
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# undef XXH32
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# undef XXH32_createState
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# undef XXH32_freeState
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# undef XXH32_reset
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# undef XXH32_update
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# undef XXH32_digest
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# undef XXH32_copyState
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# undef XXH32_canonicalFromHash
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# undef XXH32_hashFromCanonical
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/* XXH64 */
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# undef XXH64
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# undef XXH64_createState
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# undef XXH64_freeState
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# undef XXH64_reset
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# undef XXH64_update
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# undef XXH64_digest
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# undef XXH64_copyState
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# undef XXH64_canonicalFromHash
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# undef XXH64_hashFromCanonical
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/* XXH3_64bits */
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# undef XXH3_64bits
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# undef XXH3_64bits_withSecret
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# undef XXH3_64bits_withSeed
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# undef XXH3_64bits_withSecretandSeed
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# undef XXH3_createState
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# undef XXH3_freeState
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# undef XXH3_copyState
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# undef XXH3_64bits_reset
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# undef XXH3_64bits_reset_withSeed
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# undef XXH3_64bits_reset_withSecret
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# undef XXH3_64bits_update
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# undef XXH3_64bits_digest
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# undef XXH3_generateSecret
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/* XXH3_128bits */
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# undef XXH128
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# undef XXH3_128bits
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# undef XXH3_128bits_withSeed
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# undef XXH3_128bits_withSecret
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# undef XXH3_128bits_reset
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# undef XXH3_128bits_reset_withSeed
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# undef XXH3_128bits_reset_withSecret
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# undef XXH3_128bits_reset_withSecretandSeed
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# undef XXH3_128bits_update
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# undef XXH3_128bits_digest
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# undef XXH128_isEqual
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# undef XXH128_cmp
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# undef XXH128_canonicalFromHash
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# undef XXH128_hashFromCanonical
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/* Finally, free the namespace itself */
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# undef XXH_NAMESPACE
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/* employ the namespace for XXH_INLINE_ALL */
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# define XXH_NAMESPACE XXH_INLINE_
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/*
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* Some identifiers (enums, type names) are not symbols,
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* but they must nonetheless be renamed to avoid redeclaration.
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* Alternative solution: do not redeclare them.
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* However, this requires some #ifdefs, and has a more dispersed impact.
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* Meanwhile, renaming can be achieved in a single place.
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*/
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# define XXH_IPREF(Id) XXH_NAMESPACE ## Id
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# define XXH_OK XXH_IPREF(XXH_OK)
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# define XXH_ERROR XXH_IPREF(XXH_ERROR)
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# define XXH_errorcode XXH_IPREF(XXH_errorcode)
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# define XXH32_canonical_t XXH_IPREF(XXH32_canonical_t)
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# define XXH64_canonical_t XXH_IPREF(XXH64_canonical_t)
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# define XXH128_canonical_t XXH_IPREF(XXH128_canonical_t)
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# define XXH32_state_s XXH_IPREF(XXH32_state_s)
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# define XXH32_state_t XXH_IPREF(XXH32_state_t)
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# define XXH64_state_s XXH_IPREF(XXH64_state_s)
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# define XXH64_state_t XXH_IPREF(XXH64_state_t)
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# define XXH3_state_s XXH_IPREF(XXH3_state_s)
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# define XXH3_state_t XXH_IPREF(XXH3_state_t)
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# define XXH128_hash_t XXH_IPREF(XXH128_hash_t)
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/* Ensure the header is parsed again, even if it was previously included */
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# undef XXHASH_H_5627135585666179
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# undef XXHASH_H_STATIC_13879238742
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#endif /* XXH_INLINE_ALL || XXH_PRIVATE_API */
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/* ****************************************************************
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* Stable API
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*****************************************************************/
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#ifndef XXHASH_H_5627135585666179
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#define XXHASH_H_5627135585666179 1
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213
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/*!
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* @defgroup public Public API
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* Contains details on the public xxHash functions.
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* @{
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*/
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/* specific declaration modes for Windows */
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#if !defined(XXH_INLINE_ALL) && !defined(XXH_PRIVATE_API)
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# if defined(WIN32) && defined(_MSC_VER) && (defined(XXH_IMPORT) || defined(XXH_EXPORT))
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# ifdef XXH_EXPORT
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# define XXH_PUBLIC_API __declspec(dllexport)
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# elif XXH_IMPORT
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# define XXH_PUBLIC_API __declspec(dllimport)
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# endif
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# else
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# define XXH_PUBLIC_API /* do nothing */
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# endif
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#endif
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#ifdef XXH_DOXYGEN
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/*!
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* @brief Emulate a namespace by transparently prefixing all symbols.
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*
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* If you want to include _and expose_ xxHash functions from within your own
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* library, but also want to avoid symbol collisions with other libraries which
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* may also include xxHash, you can use XXH_NAMESPACE to automatically prefix
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* any public symbol from xxhash library with the value of XXH_NAMESPACE
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* (therefore, avoid empty or numeric values).
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*
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* Note that no change is required within the calling program as long as it
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* includes `xxhash.h`: Regular symbol names will be automatically translated
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* by this header.
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*/
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# define XXH_NAMESPACE /* YOUR NAME HERE */
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# undef XXH_NAMESPACE
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#endif
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#ifdef XXH_NAMESPACE
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# define XXH_CAT(A,B) A##B
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# define XXH_NAME2(A,B) XXH_CAT(A,B)
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# define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber)
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/* XXH32 */
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# define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
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# define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
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# define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
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# define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
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# define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
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# define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
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# define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState)
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# define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash)
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# define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical)
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/* XXH64 */
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# define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
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# define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
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# define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
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# define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
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# define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
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# define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
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# define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState)
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# define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash)
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# define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical)
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/* XXH3_64bits */
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# define XXH3_64bits XXH_NAME2(XXH_NAMESPACE, XXH3_64bits)
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# define XXH3_64bits_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSecret)
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# define XXH3_64bits_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSeed)
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# define XXH3_64bits_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSecretandSeed)
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# define XXH3_createState XXH_NAME2(XXH_NAMESPACE, XXH3_createState)
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# define XXH3_freeState XXH_NAME2(XXH_NAMESPACE, XXH3_freeState)
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# define XXH3_copyState XXH_NAME2(XXH_NAMESPACE, XXH3_copyState)
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# define XXH3_64bits_reset XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset)
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# define XXH3_64bits_reset_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSeed)
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# define XXH3_64bits_reset_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSecret)
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# define XXH3_64bits_reset_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSecretandSeed)
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# define XXH3_64bits_update XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_update)
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# define XXH3_64bits_digest XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_digest)
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# define XXH3_generateSecret XXH_NAME2(XXH_NAMESPACE, XXH3_generateSecret)
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# define XXH3_generateSecret_fromSeed XXH_NAME2(XXH_NAMESPACE, XXH3_generateSecret_fromSeed)
290
/* XXH3_128bits */
291
# define XXH128 XXH_NAME2(XXH_NAMESPACE, XXH128)
292
# define XXH3_128bits XXH_NAME2(XXH_NAMESPACE, XXH3_128bits)
293
# define XXH3_128bits_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSeed)
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# define XXH3_128bits_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSecret)
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# define XXH3_128bits_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSecretandSeed)
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# define XXH3_128bits_reset XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset)
297
# define XXH3_128bits_reset_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSeed)
298
# define XXH3_128bits_reset_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSecret)
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# define XXH3_128bits_reset_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSecretandSeed)
300
# define XXH3_128bits_update XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_update)
301
# define XXH3_128bits_digest XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_digest)
302
# define XXH128_isEqual XXH_NAME2(XXH_NAMESPACE, XXH128_isEqual)
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# define XXH128_cmp XXH_NAME2(XXH_NAMESPACE, XXH128_cmp)
304
# define XXH128_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH128_canonicalFromHash)
305
# define XXH128_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH128_hashFromCanonical)
306
#endif
307
308
309
/* *************************************
310
* Version
311
***************************************/
312
#define XXH_VERSION_MAJOR 0
313
#define XXH_VERSION_MINOR 8
314
#define XXH_VERSION_RELEASE 1
315
#define XXH_VERSION_NUMBER (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
316
317
/*!
318
* @brief Obtains the xxHash version.
319
*
320
* This is mostly useful when xxHash is compiled as a shared library,
321
* since the returned value comes from the library, as opposed to header file.
322
*
323
* @return `XXH_VERSION_NUMBER` of the invoked library.
324
*/
325
XXH_PUBLIC_API unsigned XXH_versionNumber (void);
326
327
328
/* ****************************
329
* Common basic types
330
******************************/
331
#include <stddef.h> /* size_t */
332
typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
333
334
335
/*-**********************************************************************
336
* 32-bit hash
337
************************************************************************/
338
#if defined(XXH_DOXYGEN) /* Don't show <stdint.h> include */
339
/*!
340
* @brief An unsigned 32-bit integer.
341
*
342
* Not necessarily defined to `uint32_t` but functionally equivalent.
343
*/
344
typedef uint32_t XXH32_hash_t;
345
346
#elif !defined (__VMS) \
347
&& (defined (__cplusplus) \
348
|| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
349
# include <stdint.h>
350
typedef uint32_t XXH32_hash_t;
351
352
#else
353
# include <limits.h>
354
# if UINT_MAX == 0xFFFFFFFFUL
355
typedef unsigned int XXH32_hash_t;
356
# else
357
# if ULONG_MAX == 0xFFFFFFFFUL
358
typedef unsigned long XXH32_hash_t;
359
# else
360
# error "unsupported platform: need a 32-bit type"
361
# endif
362
# endif
363
#endif
364
365
/*!
366
* @}
367
*
368
* @defgroup xxh32_family XXH32 family
369
* @ingroup public
370
* Contains functions used in the classic 32-bit xxHash algorithm.
371
*
372
* @note
373
* XXH32 is useful for older platforms, with no or poor 64-bit performance.
374
* Note that @ref xxh3_family provides competitive speed
375
* for both 32-bit and 64-bit systems, and offers true 64/128 bit hash results.
376
*
377
* @see @ref xxh64_family, @ref xxh3_family : Other xxHash families
378
* @see @ref xxh32_impl for implementation details
379
* @{
380
*/
381
382
/*!
383
* @brief Calculates the 32-bit hash of @p input using xxHash32.
384
*
385
* Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark): 5.4 GB/s
386
*
387
* @param input The block of data to be hashed, at least @p length bytes in size.
388
* @param length The length of @p input, in bytes.
389
* @param seed The 32-bit seed to alter the hash's output predictably.
390
*
391
* @pre
392
* The memory between @p input and @p input + @p length must be valid,
393
* readable, contiguous memory. However, if @p length is `0`, @p input may be
394
* `NULL`. In C++, this also must be *TriviallyCopyable*.
395
*
396
* @return The calculated 32-bit hash value.
397
*
398
* @see
399
* XXH64(), XXH3_64bits_withSeed(), XXH3_128bits_withSeed(), XXH128():
400
* Direct equivalents for the other variants of xxHash.
401
* @see
402
* XXH32_createState(), XXH32_update(), XXH32_digest(): Streaming version.
403
*/
404
XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, XXH32_hash_t seed);
405
406
/*!
407
* Streaming functions generate the xxHash value from an incremental input.
408
* This method is slower than single-call functions, due to state management.
409
* For small inputs, prefer `XXH32()` and `XXH64()`, which are better optimized.
410
*
411
* An XXH state must first be allocated using `XXH*_createState()`.
412
*
413
* Start a new hash by initializing the state with a seed using `XXH*_reset()`.
414
*
415
* Then, feed the hash state by calling `XXH*_update()` as many times as necessary.
416
*
417
* The function returns an error code, with 0 meaning OK, and any other value
418
* meaning there is an error.
419
*
420
* Finally, a hash value can be produced anytime, by using `XXH*_digest()`.
421
* This function returns the nn-bits hash as an int or long long.
422
*
423
* It's still possible to continue inserting input into the hash state after a
424
* digest, and generate new hash values later on by invoking `XXH*_digest()`.
425
*
426
* When done, release the state using `XXH*_freeState()`.
427
*
428
* Example code for incrementally hashing a file:
429
* @code{.c}
430
* #include <stdio.h>
431
* #include <xxhash.h>
432
* #define BUFFER_SIZE 256
433
*
434
* // Note: XXH64 and XXH3 use the same interface.
435
* XXH32_hash_t
436
* hashFile(FILE* stream)
437
* {
438
* XXH32_state_t* state;
439
* unsigned char buf[BUFFER_SIZE];
440
* size_t amt;
441
* XXH32_hash_t hash;
442
*
443
* state = XXH32_createState(); // Create a state
444
* assert(state != NULL); // Error check here
445
* XXH32_reset(state, 0xbaad5eed); // Reset state with our seed
446
* while ((amt = fread(buf, 1, sizeof(buf), stream)) != 0) {
447
* XXH32_update(state, buf, amt); // Hash the file in chunks
448
* }
449
* hash = XXH32_digest(state); // Finalize the hash
450
* XXH32_freeState(state); // Clean up
451
* return hash;
452
* }
453
* @endcode
454
*/
455
456
/*!
457
* @typedef struct XXH32_state_s XXH32_state_t
458
* @brief The opaque state struct for the XXH32 streaming API.
459
*
460
* @see XXH32_state_s for details.
461
*/
462
typedef struct XXH32_state_s XXH32_state_t;
463
464
/*!
465
* @brief Allocates an @ref XXH32_state_t.
466
*
467
* Must be freed with XXH32_freeState().
468
* @return An allocated XXH32_state_t on success, `NULL` on failure.
469
*/
470
XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void);
471
/*!
472
* @brief Frees an @ref XXH32_state_t.
473
*
474
* Must be allocated with XXH32_createState().
475
* @param statePtr A pointer to an @ref XXH32_state_t allocated with @ref XXH32_createState().
476
* @return XXH_OK.
477
*/
478
XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr);
479
/*!
480
* @brief Copies one @ref XXH32_state_t to another.
481
*
482
* @param dst_state The state to copy to.
483
* @param src_state The state to copy from.
484
* @pre
485
* @p dst_state and @p src_state must not be `NULL` and must not overlap.
486
*/
487
XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state);
488
489
/*!
490
* @brief Resets an @ref XXH32_state_t to begin a new hash.
491
*
492
* This function resets and seeds a state. Call it before @ref XXH32_update().
493
*
494
* @param statePtr The state struct to reset.
495
* @param seed The 32-bit seed to alter the hash result predictably.
496
*
497
* @pre
498
* @p statePtr must not be `NULL`.
499
*
500
* @return @ref XXH_OK on success, @ref XXH_ERROR on failure.
501
*/
502
XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, XXH32_hash_t seed);
503
504
/*!
505
* @brief Consumes a block of @p input to an @ref XXH32_state_t.
506
*
507
* Call this to incrementally consume blocks of data.
508
*
509
* @param statePtr The state struct to update.
510
* @param input The block of data to be hashed, at least @p length bytes in size.
511
* @param length The length of @p input, in bytes.
512
*
513
* @pre
514
* @p statePtr must not be `NULL`.
515
* @pre
516
* The memory between @p input and @p input + @p length must be valid,
517
* readable, contiguous memory. However, if @p length is `0`, @p input may be
518
* `NULL`. In C++, this also must be *TriviallyCopyable*.
519
*
520
* @return @ref XXH_OK on success, @ref XXH_ERROR on failure.
521
*/
522
XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
523
524
/*!
525
* @brief Returns the calculated hash value from an @ref XXH32_state_t.
526
*
527
* @note
528
* Calling XXH32_digest() will not affect @p statePtr, so you can update,
529
* digest, and update again.
530
*
531
* @param statePtr The state struct to calculate the hash from.
532
*
533
* @pre
534
* @p statePtr must not be `NULL`.
535
*
536
* @return The calculated xxHash32 value from that state.
537
*/
538
XXH_PUBLIC_API XXH32_hash_t XXH32_digest (const XXH32_state_t* statePtr);
539
540
/******* Canonical representation *******/
541
542
/*
543
* The default return values from XXH functions are unsigned 32 and 64 bit
544
* integers.
545
* This the simplest and fastest format for further post-processing.
546
*
547
* However, this leaves open the question of what is the order on the byte level,
548
* since little and big endian conventions will store the same number differently.
549
*
550
* The canonical representation settles this issue by mandating big-endian
551
* convention, the same convention as human-readable numbers (large digits first).
552
*
553
* When writing hash values to storage, sending them over a network, or printing
554
* them, it's highly recommended to use the canonical representation to ensure
555
* portability across a wider range of systems, present and future.
556
*
557
* The following functions allow transformation of hash values to and from
558
* canonical format.
559
*/
560
561
/*!
562
* @brief Canonical (big endian) representation of @ref XXH32_hash_t.
563
*/
564
typedef struct {
565
unsigned char digest[4]; /*!< Hash bytes, big endian */
566
} XXH32_canonical_t;
567
568
/*!
569
* @brief Converts an @ref XXH32_hash_t to a big endian @ref XXH32_canonical_t.
570
*
571
* @param dst The @ref XXH32_canonical_t pointer to be stored to.
572
* @param hash The @ref XXH32_hash_t to be converted.
573
*
574
* @pre
575
* @p dst must not be `NULL`.
576
*/
577
XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
578
579
/*!
580
* @brief Converts an @ref XXH32_canonical_t to a native @ref XXH32_hash_t.
581
*
582
* @param src The @ref XXH32_canonical_t to convert.
583
*
584
* @pre
585
* @p src must not be `NULL`.
586
*
587
* @return The converted hash.
588
*/
589
XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src);
590
591
592
#ifdef __has_attribute
593
# define XXH_HAS_ATTRIBUTE(x) __has_attribute(x)
594
#else
595
# define XXH_HAS_ATTRIBUTE(x) 0
596
#endif
597
598
/* C-language Attributes are added in C23. */
599
#if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
600
# define XXH_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
601
#else
602
# define XXH_HAS_C_ATTRIBUTE(x) 0
603
#endif
604
605
#if defined(__cplusplus) && defined(__has_cpp_attribute)
606
# define XXH_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
607
#else
608
# define XXH_HAS_CPP_ATTRIBUTE(x) 0
609
#endif
610
611
/*
612
Define XXH_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute
613
introduced in CPP17 and C23.
614
CPP17 : https://en.cppreference.com/w/cpp/language/attributes/fallthrough
615
C23 : https://en.cppreference.com/w/c/language/attributes/fallthrough
616
*/
617
#if XXH_HAS_C_ATTRIBUTE(x)
618
# define XXH_FALLTHROUGH [[fallthrough]]
619
#elif XXH_HAS_CPP_ATTRIBUTE(x)
620
# define XXH_FALLTHROUGH [[fallthrough]]
621
#elif XXH_HAS_ATTRIBUTE(__fallthrough__)
622
# define XXH_FALLTHROUGH __attribute__ ((fallthrough))
623
#else
624
# define XXH_FALLTHROUGH
625
#endif
626
627
/*!
628
* @}
629
* @ingroup public
630
* @{
631
*/
632
633
#ifndef XXH_NO_LONG_LONG
634
/*-**********************************************************************
635
* 64-bit hash
636
************************************************************************/
637
#if defined(XXH_DOXYGEN) /* don't include <stdint.h> */
638
/*!
639
* @brief An unsigned 64-bit integer.
640
*
641
* Not necessarily defined to `uint64_t` but functionally equivalent.
642
*/
643
typedef uint64_t XXH64_hash_t;
644
#elif !defined (__VMS) \
645
&& (defined (__cplusplus) \
646
|| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
647
# include <stdint.h>
648
typedef uint64_t XXH64_hash_t;
649
#else
650
# include <limits.h>
651
# if defined(__LP64__) && ULONG_MAX == 0xFFFFFFFFFFFFFFFFULL
652
/* LP64 ABI says uint64_t is unsigned long */
653
typedef unsigned long XXH64_hash_t;
654
# else
655
/* the following type must have a width of 64-bit */
656
typedef unsigned long long XXH64_hash_t;
657
# endif
658
#endif
659
660
/*!
661
* @}
662
*
663
* @defgroup xxh64_family XXH64 family
664
* @ingroup public
665
* @{
666
* Contains functions used in the classic 64-bit xxHash algorithm.
667
*
668
* @note
669
* XXH3 provides competitive speed for both 32-bit and 64-bit systems,
670
* and offers true 64/128 bit hash results.
671
* It provides better speed for systems with vector processing capabilities.
672
*/
673
674
675
/*!
676
* @brief Calculates the 64-bit hash of @p input using xxHash64.
677
*
678
* This function usually runs faster on 64-bit systems, but slower on 32-bit
679
* systems (see benchmark).
680
*
681
* @param input The block of data to be hashed, at least @p length bytes in size.
682
* @param length The length of @p input, in bytes.
683
* @param seed The 64-bit seed to alter the hash's output predictably.
684
*
685
* @pre
686
* The memory between @p input and @p input + @p length must be valid,
687
* readable, contiguous memory. However, if @p length is `0`, @p input may be
688
* `NULL`. In C++, this also must be *TriviallyCopyable*.
689
*
690
* @return The calculated 64-bit hash.
691
*
692
* @see
693
* XXH32(), XXH3_64bits_withSeed(), XXH3_128bits_withSeed(), XXH128():
694
* Direct equivalents for the other variants of xxHash.
695
* @see
696
* XXH64_createState(), XXH64_update(), XXH64_digest(): Streaming version.
697
*/
698
/* Begin FreeBSD - This symbol is needed by dll-linked CLI zstd(1). */
699
__attribute__((visibility ("default")))
700
/* End FreeBSD */
701
XXH_PUBLIC_API XXH64_hash_t XXH64(const void* input, size_t length, XXH64_hash_t seed);
702
703
/******* Streaming *******/
704
/*!
705
* @brief The opaque state struct for the XXH64 streaming API.
706
*
707
* @see XXH64_state_s for details.
708
*/
709
typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */
710
XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void);
711
XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr);
712
XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state);
713
714
XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH64_state_t* statePtr, XXH64_hash_t seed);
715
XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
716
XXH_PUBLIC_API XXH64_hash_t XXH64_digest (const XXH64_state_t* statePtr);
717
718
/******* Canonical representation *******/
719
typedef struct { unsigned char digest[sizeof(XXH64_hash_t)]; } XXH64_canonical_t;
720
XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
721
XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src);
722
723
#ifndef XXH_NO_XXH3
724
/*!
725
* @}
726
* ************************************************************************
727
* @defgroup xxh3_family XXH3 family
728
* @ingroup public
729
* @{
730
*
731
* XXH3 is a more recent hash algorithm featuring:
732
* - Improved speed for both small and large inputs
733
* - True 64-bit and 128-bit outputs
734
* - SIMD acceleration
735
* - Improved 32-bit viability
736
*
737
* Speed analysis methodology is explained here:
738
*
739
* https://fastcompression.blogspot.com/2019/03/presenting-xxh3.html
740
*
741
* Compared to XXH64, expect XXH3 to run approximately
742
* ~2x faster on large inputs and >3x faster on small ones,
743
* exact differences vary depending on platform.
744
*
745
* XXH3's speed benefits greatly from SIMD and 64-bit arithmetic,
746
* but does not require it.
747
* Any 32-bit and 64-bit targets that can run XXH32 smoothly
748
* can run XXH3 at competitive speeds, even without vector support.
749
* Further details are explained in the implementation.
750
*
751
* Optimized implementations are provided for AVX512, AVX2, SSE2, NEON, POWER8,
752
* ZVector and scalar targets. This can be controlled via the XXH_VECTOR macro.
753
*
754
* XXH3 implementation is portable:
755
* it has a generic C90 formulation that can be compiled on any platform,
756
* all implementations generage exactly the same hash value on all platforms.
757
* Starting from v0.8.0, it's also labelled "stable", meaning that
758
* any future version will also generate the same hash value.
759
*
760
* XXH3 offers 2 variants, _64bits and _128bits.
761
*
762
* When only 64 bits are needed, prefer invoking the _64bits variant, as it
763
* reduces the amount of mixing, resulting in faster speed on small inputs.
764
* It's also generally simpler to manipulate a scalar return type than a struct.
765
*
766
* The API supports one-shot hashing, streaming mode, and custom secrets.
767
*/
768
769
/*-**********************************************************************
770
* XXH3 64-bit variant
771
************************************************************************/
772
773
/* XXH3_64bits():
774
* default 64-bit variant, using default secret and default seed of 0.
775
* It's the fastest variant. */
776
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits(const void* data, size_t len);
777
778
/*
779
* XXH3_64bits_withSeed():
780
* This variant generates a custom secret on the fly
781
* based on default secret altered using the `seed` value.
782
* While this operation is decently fast, note that it's not completely free.
783
* Note: seed==0 produces the same results as XXH3_64bits().
784
*/
785
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_withSeed(const void* data, size_t len, XXH64_hash_t seed);
786
787
/*!
788
* The bare minimum size for a custom secret.
789
*
790
* @see
791
* XXH3_64bits_withSecret(), XXH3_64bits_reset_withSecret(),
792
* XXH3_128bits_withSecret(), XXH3_128bits_reset_withSecret().
793
*/
794
#define XXH3_SECRET_SIZE_MIN 136
795
796
/*
797
* XXH3_64bits_withSecret():
798
* It's possible to provide any blob of bytes as a "secret" to generate the hash.
799
* This makes it more difficult for an external actor to prepare an intentional collision.
800
* The main condition is that secretSize *must* be large enough (>= XXH3_SECRET_SIZE_MIN).
801
* However, the quality of the secret impacts the dispersion of the hash algorithm.
802
* Therefore, the secret _must_ look like a bunch of random bytes.
803
* Avoid "trivial" or structured data such as repeated sequences or a text document.
804
* Whenever in doubt about the "randomness" of the blob of bytes,
805
* consider employing "XXH3_generateSecret()" instead (see below).
806
* It will generate a proper high entropy secret derived from the blob of bytes.
807
* Another advantage of using XXH3_generateSecret() is that
808
* it guarantees that all bits within the initial blob of bytes
809
* will impact every bit of the output.
810
* This is not necessarily the case when using the blob of bytes directly
811
* because, when hashing _small_ inputs, only a portion of the secret is employed.
812
*/
813
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_withSecret(const void* data, size_t len, const void* secret, size_t secretSize);
814
815
816
/******* Streaming *******/
817
/*
818
* Streaming requires state maintenance.
819
* This operation costs memory and CPU.
820
* As a consequence, streaming is slower than one-shot hashing.
821
* For better performance, prefer one-shot functions whenever applicable.
822
*/
823
824
/*!
825
* @brief The state struct for the XXH3 streaming API.
826
*
827
* @see XXH3_state_s for details.
828
*/
829
typedef struct XXH3_state_s XXH3_state_t;
830
XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void);
831
XXH_PUBLIC_API XXH_errorcode XXH3_freeState(XXH3_state_t* statePtr);
832
XXH_PUBLIC_API void XXH3_copyState(XXH3_state_t* dst_state, const XXH3_state_t* src_state);
833
834
/*
835
* XXH3_64bits_reset():
836
* Initialize with default parameters.
837
* digest will be equivalent to `XXH3_64bits()`.
838
*/
839
XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset(XXH3_state_t* statePtr);
840
/*
841
* XXH3_64bits_reset_withSeed():
842
* Generate a custom secret from `seed`, and store it into `statePtr`.
843
* digest will be equivalent to `XXH3_64bits_withSeed()`.
844
*/
845
XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed);
846
/*
847
* XXH3_64bits_reset_withSecret():
848
* `secret` is referenced, it _must outlive_ the hash streaming session.
849
* Similar to one-shot API, `secretSize` must be >= `XXH3_SECRET_SIZE_MIN`,
850
* and the quality of produced hash values depends on secret's entropy
851
* (secret's content should look like a bunch of random bytes).
852
* When in doubt about the randomness of a candidate `secret`,
853
* consider employing `XXH3_generateSecret()` instead (see below).
854
*/
855
XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize);
856
857
XXH_PUBLIC_API XXH_errorcode XXH3_64bits_update (XXH3_state_t* statePtr, const void* input, size_t length);
858
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_digest (const XXH3_state_t* statePtr);
859
860
/* note : canonical representation of XXH3 is the same as XXH64
861
* since they both produce XXH64_hash_t values */
862
863
864
/*-**********************************************************************
865
* XXH3 128-bit variant
866
************************************************************************/
867
868
/*!
869
* @brief The return value from 128-bit hashes.
870
*
871
* Stored in little endian order, although the fields themselves are in native
872
* endianness.
873
*/
874
typedef struct {
875
XXH64_hash_t low64; /*!< `value & 0xFFFFFFFFFFFFFFFF` */
876
XXH64_hash_t high64; /*!< `value >> 64` */
877
} XXH128_hash_t;
878
879
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits(const void* data, size_t len);
880
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_withSeed(const void* data, size_t len, XXH64_hash_t seed);
881
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_withSecret(const void* data, size_t len, const void* secret, size_t secretSize);
882
883
/******* Streaming *******/
884
/*
885
* Streaming requires state maintenance.
886
* This operation costs memory and CPU.
887
* As a consequence, streaming is slower than one-shot hashing.
888
* For better performance, prefer one-shot functions whenever applicable.
889
*
890
* XXH3_128bits uses the same XXH3_state_t as XXH3_64bits().
891
* Use already declared XXH3_createState() and XXH3_freeState().
892
*
893
* All reset and streaming functions have same meaning as their 64-bit counterpart.
894
*/
895
896
XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset(XXH3_state_t* statePtr);
897
XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed);
898
XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize);
899
900
XXH_PUBLIC_API XXH_errorcode XXH3_128bits_update (XXH3_state_t* statePtr, const void* input, size_t length);
901
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_digest (const XXH3_state_t* statePtr);
902
903
/* Following helper functions make it possible to compare XXH128_hast_t values.
904
* Since XXH128_hash_t is a structure, this capability is not offered by the language.
905
* Note: For better performance, these functions can be inlined using XXH_INLINE_ALL */
906
907
/*!
908
* XXH128_isEqual():
909
* Return: 1 if `h1` and `h2` are equal, 0 if they are not.
910
*/
911
XXH_PUBLIC_API int XXH128_isEqual(XXH128_hash_t h1, XXH128_hash_t h2);
912
913
/*!
914
* XXH128_cmp():
915
*
916
* This comparator is compatible with stdlib's `qsort()`/`bsearch()`.
917
*
918
* return: >0 if *h128_1 > *h128_2
919
* =0 if *h128_1 == *h128_2
920
* <0 if *h128_1 < *h128_2
921
*/
922
XXH_PUBLIC_API int XXH128_cmp(const void* h128_1, const void* h128_2);
923
924
925
/******* Canonical representation *******/
926
typedef struct { unsigned char digest[sizeof(XXH128_hash_t)]; } XXH128_canonical_t;
927
XXH_PUBLIC_API void XXH128_canonicalFromHash(XXH128_canonical_t* dst, XXH128_hash_t hash);
928
XXH_PUBLIC_API XXH128_hash_t XXH128_hashFromCanonical(const XXH128_canonical_t* src);
929
930
931
#endif /* !XXH_NO_XXH3 */
932
#endif /* XXH_NO_LONG_LONG */
933
934
/*!
935
* @}
936
*/
937
#endif /* XXHASH_H_5627135585666179 */
938
939
940
941
#if defined(XXH_STATIC_LINKING_ONLY) && !defined(XXHASH_H_STATIC_13879238742)
942
#define XXHASH_H_STATIC_13879238742
943
/* ****************************************************************************
944
* This section contains declarations which are not guaranteed to remain stable.
945
* They may change in future versions, becoming incompatible with a different
946
* version of the library.
947
* These declarations should only be used with static linking.
948
* Never use them in association with dynamic linking!
949
***************************************************************************** */
950
951
/*
952
* These definitions are only present to allow static allocation
953
* of XXH states, on stack or in a struct, for example.
954
* Never **ever** access their members directly.
955
*/
956
957
/*!
958
* @internal
959
* @brief Structure for XXH32 streaming API.
960
*
961
* @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
962
* @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined. Otherwise it is
963
* an opaque type. This allows fields to safely be changed.
964
*
965
* Typedef'd to @ref XXH32_state_t.
966
* Do not access the members of this struct directly.
967
* @see XXH64_state_s, XXH3_state_s
968
*/
969
struct XXH32_state_s {
970
XXH32_hash_t total_len_32; /*!< Total length hashed, modulo 2^32 */
971
XXH32_hash_t large_len; /*!< Whether the hash is >= 16 (handles @ref total_len_32 overflow) */
972
XXH32_hash_t v[4]; /*!< Accumulator lanes */
973
XXH32_hash_t mem32[4]; /*!< Internal buffer for partial reads. Treated as unsigned char[16]. */
974
XXH32_hash_t memsize; /*!< Amount of data in @ref mem32 */
975
XXH32_hash_t reserved; /*!< Reserved field. Do not read nor write to it. */
976
}; /* typedef'd to XXH32_state_t */
977
978
979
#ifndef XXH_NO_LONG_LONG /* defined when there is no 64-bit support */
980
981
/*!
982
* @internal
983
* @brief Structure for XXH64 streaming API.
984
*
985
* @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
986
* @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined. Otherwise it is
987
* an opaque type. This allows fields to safely be changed.
988
*
989
* Typedef'd to @ref XXH64_state_t.
990
* Do not access the members of this struct directly.
991
* @see XXH32_state_s, XXH3_state_s
992
*/
993
struct XXH64_state_s {
994
XXH64_hash_t total_len; /*!< Total length hashed. This is always 64-bit. */
995
XXH64_hash_t v[4]; /*!< Accumulator lanes */
996
XXH64_hash_t mem64[4]; /*!< Internal buffer for partial reads. Treated as unsigned char[32]. */
997
XXH32_hash_t memsize; /*!< Amount of data in @ref mem64 */
998
XXH32_hash_t reserved32; /*!< Reserved field, needed for padding anyways*/
999
XXH64_hash_t reserved64; /*!< Reserved field. Do not read or write to it. */
1000
}; /* typedef'd to XXH64_state_t */
1001
1002
1003
#ifndef XXH_NO_XXH3
1004
1005
#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) /* >= C11 */
1006
# include <stdalign.h>
1007
# define XXH_ALIGN(n) alignas(n)
1008
#elif defined(__cplusplus) && (__cplusplus >= 201103L) /* >= C++11 */
1009
/* In C++ alignas() is a keyword */
1010
# define XXH_ALIGN(n) alignas(n)
1011
#elif defined(__GNUC__)
1012
# define XXH_ALIGN(n) __attribute__ ((aligned(n)))
1013
#elif defined(_MSC_VER)
1014
# define XXH_ALIGN(n) __declspec(align(n))
1015
#else
1016
# define XXH_ALIGN(n) /* disabled */
1017
#endif
1018
1019
/* Old GCC versions only accept the attribute after the type in structures. */
1020
#if !(defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)) /* C11+ */ \
1021
&& ! (defined(__cplusplus) && (__cplusplus >= 201103L)) /* >= C++11 */ \
1022
&& defined(__GNUC__)
1023
# define XXH_ALIGN_MEMBER(align, type) type XXH_ALIGN(align)
1024
#else
1025
# define XXH_ALIGN_MEMBER(align, type) XXH_ALIGN(align) type
1026
#endif
1027
1028
/*!
1029
* @brief The size of the internal XXH3 buffer.
1030
*
1031
* This is the optimal update size for incremental hashing.
1032
*
1033
* @see XXH3_64b_update(), XXH3_128b_update().
1034
*/
1035
#define XXH3_INTERNALBUFFER_SIZE 256
1036
1037
/*!
1038
* @brief Default size of the secret buffer (and @ref XXH3_kSecret).
1039
*
1040
* This is the size used in @ref XXH3_kSecret and the seeded functions.
1041
*
1042
* Not to be confused with @ref XXH3_SECRET_SIZE_MIN.
1043
*/
1044
#define XXH3_SECRET_DEFAULT_SIZE 192
1045
1046
/*!
1047
* @internal
1048
* @brief Structure for XXH3 streaming API.
1049
*
1050
* @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
1051
* @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined.
1052
* Otherwise it is an opaque type.
1053
* Never use this definition in combination with dynamic library.
1054
* This allows fields to safely be changed in the future.
1055
*
1056
* @note ** This structure has a strict alignment requirement of 64 bytes!! **
1057
* Do not allocate this with `malloc()` or `new`,
1058
* it will not be sufficiently aligned.
1059
* Use @ref XXH3_createState() and @ref XXH3_freeState(), or stack allocation.
1060
*
1061
* Typedef'd to @ref XXH3_state_t.
1062
* Do never access the members of this struct directly.
1063
*
1064
* @see XXH3_INITSTATE() for stack initialization.
1065
* @see XXH3_createState(), XXH3_freeState().
1066
* @see XXH32_state_s, XXH64_state_s
1067
*/
1068
struct XXH3_state_s {
1069
XXH_ALIGN_MEMBER(64, XXH64_hash_t acc[8]);
1070
/*!< The 8 accumulators. Similar to `vN` in @ref XXH32_state_s::v1 and @ref XXH64_state_s */
1071
XXH_ALIGN_MEMBER(64, unsigned char customSecret[XXH3_SECRET_DEFAULT_SIZE]);
1072
/*!< Used to store a custom secret generated from a seed. */
1073
XXH_ALIGN_MEMBER(64, unsigned char buffer[XXH3_INTERNALBUFFER_SIZE]);
1074
/*!< The internal buffer. @see XXH32_state_s::mem32 */
1075
XXH32_hash_t bufferedSize;
1076
/*!< The amount of memory in @ref buffer, @see XXH32_state_s::memsize */
1077
XXH32_hash_t useSeed;
1078
/*!< Reserved field. Needed for padding on 64-bit. */
1079
size_t nbStripesSoFar;
1080
/*!< Number or stripes processed. */
1081
XXH64_hash_t totalLen;
1082
/*!< Total length hashed. 64-bit even on 32-bit targets. */
1083
size_t nbStripesPerBlock;
1084
/*!< Number of stripes per block. */
1085
size_t secretLimit;
1086
/*!< Size of @ref customSecret or @ref extSecret */
1087
XXH64_hash_t seed;
1088
/*!< Seed for _withSeed variants. Must be zero otherwise, @see XXH3_INITSTATE() */
1089
XXH64_hash_t reserved64;
1090
/*!< Reserved field. */
1091
const unsigned char* extSecret;
1092
/*!< Reference to an external secret for the _withSecret variants, NULL
1093
* for other variants. */
1094
/* note: there may be some padding at the end due to alignment on 64 bytes */
1095
}; /* typedef'd to XXH3_state_t */
1096
1097
#undef XXH_ALIGN_MEMBER
1098
1099
/*!
1100
* @brief Initializes a stack-allocated `XXH3_state_s`.
1101
*
1102
* When the @ref XXH3_state_t structure is merely emplaced on stack,
1103
* it should be initialized with XXH3_INITSTATE() or a memset()
1104
* in case its first reset uses XXH3_NNbits_reset_withSeed().
1105
* This init can be omitted if the first reset uses default or _withSecret mode.
1106
* This operation isn't necessary when the state is created with XXH3_createState().
1107
* Note that this doesn't prepare the state for a streaming operation,
1108
* it's still necessary to use XXH3_NNbits_reset*() afterwards.
1109
*/
1110
#define XXH3_INITSTATE(XXH3_state_ptr) { (XXH3_state_ptr)->seed = 0; }
1111
1112
1113
/* XXH128() :
1114
* simple alias to pre-selected XXH3_128bits variant
1115
*/
1116
XXH_PUBLIC_API XXH128_hash_t XXH128(const void* data, size_t len, XXH64_hash_t seed);
1117
1118
1119
/* === Experimental API === */
1120
/* Symbols defined below must be considered tied to a specific library version. */
1121
1122
/*
1123
* XXH3_generateSecret():
1124
*
1125
* Derive a high-entropy secret from any user-defined content, named customSeed.
1126
* The generated secret can be used in combination with `*_withSecret()` functions.
1127
* The `_withSecret()` variants are useful to provide a higher level of protection than 64-bit seed,
1128
* as it becomes much more difficult for an external actor to guess how to impact the calculation logic.
1129
*
1130
* The function accepts as input a custom seed of any length and any content,
1131
* and derives from it a high-entropy secret of length @secretSize
1132
* into an already allocated buffer @secretBuffer.
1133
* @secretSize must be >= XXH3_SECRET_SIZE_MIN
1134
*
1135
* The generated secret can then be used with any `*_withSecret()` variant.
1136
* Functions `XXH3_128bits_withSecret()`, `XXH3_64bits_withSecret()`,
1137
* `XXH3_128bits_reset_withSecret()` and `XXH3_64bits_reset_withSecret()`
1138
* are part of this list. They all accept a `secret` parameter
1139
* which must be large enough for implementation reasons (>= XXH3_SECRET_SIZE_MIN)
1140
* _and_ feature very high entropy (consist of random-looking bytes).
1141
* These conditions can be a high bar to meet, so
1142
* XXH3_generateSecret() can be employed to ensure proper quality.
1143
*
1144
* customSeed can be anything. It can have any size, even small ones,
1145
* and its content can be anything, even "poor entropy" sources such as a bunch of zeroes.
1146
* The resulting `secret` will nonetheless provide all required qualities.
1147
*
1148
* When customSeedSize > 0, supplying NULL as customSeed is undefined behavior.
1149
*/
1150
XXH_PUBLIC_API XXH_errorcode XXH3_generateSecret(void* secretBuffer, size_t secretSize, const void* customSeed, size_t customSeedSize);
1151
1152
1153
/*
1154
* XXH3_generateSecret_fromSeed():
1155
*
1156
* Generate the same secret as the _withSeed() variants.
1157
*
1158
* The resulting secret has a length of XXH3_SECRET_DEFAULT_SIZE (necessarily).
1159
* @secretBuffer must be already allocated, of size at least XXH3_SECRET_DEFAULT_SIZE bytes.
1160
*
1161
* The generated secret can be used in combination with
1162
*`*_withSecret()` and `_withSecretandSeed()` variants.
1163
* This generator is notably useful in combination with `_withSecretandSeed()`,
1164
* as a way to emulate a faster `_withSeed()` variant.
1165
*/
1166
XXH_PUBLIC_API void XXH3_generateSecret_fromSeed(void* secretBuffer, XXH64_hash_t seed);
1167
1168
/*
1169
* *_withSecretandSeed() :
1170
* These variants generate hash values using either
1171
* @seed for "short" keys (< XXH3_MIDSIZE_MAX = 240 bytes)
1172
* or @secret for "large" keys (>= XXH3_MIDSIZE_MAX).
1173
*
1174
* This generally benefits speed, compared to `_withSeed()` or `_withSecret()`.
1175
* `_withSeed()` has to generate the secret on the fly for "large" keys.
1176
* It's fast, but can be perceptible for "not so large" keys (< 1 KB).
1177
* `_withSecret()` has to generate the masks on the fly for "small" keys,
1178
* which requires more instructions than _withSeed() variants.
1179
* Therefore, _withSecretandSeed variant combines the best of both worlds.
1180
*
1181
* When @secret has been generated by XXH3_generateSecret_fromSeed(),
1182
* this variant produces *exactly* the same results as `_withSeed()` variant,
1183
* hence offering only a pure speed benefit on "large" input,
1184
* by skipping the need to regenerate the secret for every large input.
1185
*
1186
* Another usage scenario is to hash the secret to a 64-bit hash value,
1187
* for example with XXH3_64bits(), which then becomes the seed,
1188
* and then employ both the seed and the secret in _withSecretandSeed().
1189
* On top of speed, an added benefit is that each bit in the secret
1190
* has a 50% chance to swap each bit in the output,
1191
* via its impact to the seed.
1192
* This is not guaranteed when using the secret directly in "small data" scenarios,
1193
* because only portions of the secret are employed for small data.
1194
*/
1195
XXH_PUBLIC_API XXH64_hash_t
1196
XXH3_64bits_withSecretandSeed(const void* data, size_t len,
1197
const void* secret, size_t secretSize,
1198
XXH64_hash_t seed);
1199
1200
XXH_PUBLIC_API XXH128_hash_t
1201
XXH3_128bits_withSecretandSeed(const void* data, size_t len,
1202
const void* secret, size_t secretSize,
1203
XXH64_hash_t seed64);
1204
1205
XXH_PUBLIC_API XXH_errorcode
1206
XXH3_64bits_reset_withSecretandSeed(XXH3_state_t* statePtr,
1207
const void* secret, size_t secretSize,
1208
XXH64_hash_t seed64);
1209
1210
XXH_PUBLIC_API XXH_errorcode
1211
XXH3_128bits_reset_withSecretandSeed(XXH3_state_t* statePtr,
1212
const void* secret, size_t secretSize,
1213
XXH64_hash_t seed64);
1214
1215
1216
#endif /* XXH_NO_XXH3 */
1217
#endif /* XXH_NO_LONG_LONG */
1218
#if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)
1219
# define XXH_IMPLEMENTATION
1220
#endif
1221
1222
#endif /* defined(XXH_STATIC_LINKING_ONLY) && !defined(XXHASH_H_STATIC_13879238742) */
1223
1224
1225
/* ======================================================================== */
1226
/* ======================================================================== */
1227
/* ======================================================================== */
1228
1229
1230
/*-**********************************************************************
1231
* xxHash implementation
1232
*-**********************************************************************
1233
* xxHash's implementation used to be hosted inside xxhash.c.
1234
*
1235
* However, inlining requires implementation to be visible to the compiler,
1236
* hence be included alongside the header.
1237
* Previously, implementation was hosted inside xxhash.c,
1238
* which was then #included when inlining was activated.
1239
* This construction created issues with a few build and install systems,
1240
* as it required xxhash.c to be stored in /include directory.
1241
*
1242
* xxHash implementation is now directly integrated within xxhash.h.
1243
* As a consequence, xxhash.c is no longer needed in /include.
1244
*
1245
* xxhash.c is still available and is still useful.
1246
* In a "normal" setup, when xxhash is not inlined,
1247
* xxhash.h only exposes the prototypes and public symbols,
1248
* while xxhash.c can be built into an object file xxhash.o
1249
* which can then be linked into the final binary.
1250
************************************************************************/
1251
1252
#if ( defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API) \
1253
|| defined(XXH_IMPLEMENTATION) ) && !defined(XXH_IMPLEM_13a8737387)
1254
# define XXH_IMPLEM_13a8737387
1255
1256
/* *************************************
1257
* Tuning parameters
1258
***************************************/
1259
1260
/*!
1261
* @defgroup tuning Tuning parameters
1262
* @{
1263
*
1264
* Various macros to control xxHash's behavior.
1265
*/
1266
#ifdef XXH_DOXYGEN
1267
/*!
1268
* @brief Define this to disable 64-bit code.
1269
*
1270
* Useful if only using the @ref xxh32_family and you have a strict C90 compiler.
1271
*/
1272
# define XXH_NO_LONG_LONG
1273
# undef XXH_NO_LONG_LONG /* don't actually */
1274
/*!
1275
* @brief Controls how unaligned memory is accessed.
1276
*
1277
* By default, access to unaligned memory is controlled by `memcpy()`, which is
1278
* safe and portable.
1279
*
1280
* Unfortunately, on some target/compiler combinations, the generated assembly
1281
* is sub-optimal.
1282
*
1283
* The below switch allow selection of a different access method
1284
* in the search for improved performance.
1285
*
1286
* @par Possible options:
1287
*
1288
* - `XXH_FORCE_MEMORY_ACCESS=0` (default): `memcpy`
1289
* @par
1290
* Use `memcpy()`. Safe and portable. Note that most modern compilers will
1291
* eliminate the function call and treat it as an unaligned access.
1292
*
1293
* - `XXH_FORCE_MEMORY_ACCESS=1`: `__attribute__((packed))`
1294
* @par
1295
* Depends on compiler extensions and is therefore not portable.
1296
* This method is safe _if_ your compiler supports it,
1297
* and *generally* as fast or faster than `memcpy`.
1298
*
1299
* - `XXH_FORCE_MEMORY_ACCESS=2`: Direct cast
1300
* @par
1301
* Casts directly and dereferences. This method doesn't depend on the
1302
* compiler, but it violates the C standard as it directly dereferences an
1303
* unaligned pointer. It can generate buggy code on targets which do not
1304
* support unaligned memory accesses, but in some circumstances, it's the
1305
* only known way to get the most performance.
1306
*
1307
* - `XXH_FORCE_MEMORY_ACCESS=3`: Byteshift
1308
* @par
1309
* Also portable. This can generate the best code on old compilers which don't
1310
* inline small `memcpy()` calls, and it might also be faster on big-endian
1311
* systems which lack a native byteswap instruction. However, some compilers
1312
* will emit literal byteshifts even if the target supports unaligned access.
1313
* .
1314
*
1315
* @warning
1316
* Methods 1 and 2 rely on implementation-defined behavior. Use these with
1317
* care, as what works on one compiler/platform/optimization level may cause
1318
* another to read garbage data or even crash.
1319
*
1320
* See http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html for details.
1321
*
1322
* Prefer these methods in priority order (0 > 3 > 1 > 2)
1323
*/
1324
# define XXH_FORCE_MEMORY_ACCESS 0
1325
1326
/*!
1327
* @def XXH_FORCE_ALIGN_CHECK
1328
* @brief If defined to non-zero, adds a special path for aligned inputs (XXH32()
1329
* and XXH64() only).
1330
*
1331
* This is an important performance trick for architectures without decent
1332
* unaligned memory access performance.
1333
*
1334
* It checks for input alignment, and when conditions are met, uses a "fast
1335
* path" employing direct 32-bit/64-bit reads, resulting in _dramatically
1336
* faster_ read speed.
1337
*
1338
* The check costs one initial branch per hash, which is generally negligible,
1339
* but not zero.
1340
*
1341
* Moreover, it's not useful to generate an additional code path if memory
1342
* access uses the same instruction for both aligned and unaligned
1343
* addresses (e.g. x86 and aarch64).
1344
*
1345
* In these cases, the alignment check can be removed by setting this macro to 0.
1346
* Then the code will always use unaligned memory access.
1347
* Align check is automatically disabled on x86, x64 & arm64,
1348
* which are platforms known to offer good unaligned memory accesses performance.
1349
*
1350
* This option does not affect XXH3 (only XXH32 and XXH64).
1351
*/
1352
# define XXH_FORCE_ALIGN_CHECK 0
1353
1354
/*!
1355
* @def XXH_NO_INLINE_HINTS
1356
* @brief When non-zero, sets all functions to `static`.
1357
*
1358
* By default, xxHash tries to force the compiler to inline almost all internal
1359
* functions.
1360
*
1361
* This can usually improve performance due to reduced jumping and improved
1362
* constant folding, but significantly increases the size of the binary which
1363
* might not be favorable.
1364
*
1365
* Additionally, sometimes the forced inlining can be detrimental to performance,
1366
* depending on the architecture.
1367
*
1368
* XXH_NO_INLINE_HINTS marks all internal functions as static, giving the
1369
* compiler full control on whether to inline or not.
1370
*
1371
* When not optimizing (-O0), optimizing for size (-Os, -Oz), or using
1372
* -fno-inline with GCC or Clang, this will automatically be defined.
1373
*/
1374
# define XXH_NO_INLINE_HINTS 0
1375
1376
/*!
1377
* @def XXH32_ENDJMP
1378
* @brief Whether to use a jump for `XXH32_finalize`.
1379
*
1380
* For performance, `XXH32_finalize` uses multiple branches in the finalizer.
1381
* This is generally preferable for performance,
1382
* but depending on exact architecture, a jmp may be preferable.
1383
*
1384
* This setting is only possibly making a difference for very small inputs.
1385
*/
1386
# define XXH32_ENDJMP 0
1387
1388
/*!
1389
* @internal
1390
* @brief Redefines old internal names.
1391
*
1392
* For compatibility with code that uses xxHash's internals before the names
1393
* were changed to improve namespacing. There is no other reason to use this.
1394
*/
1395
# define XXH_OLD_NAMES
1396
# undef XXH_OLD_NAMES /* don't actually use, it is ugly. */
1397
#endif /* XXH_DOXYGEN */
1398
/*!
1399
* @}
1400
*/
1401
1402
#ifndef XXH_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */
1403
/* prefer __packed__ structures (method 1) for gcc on armv7+ and mips */
1404
# if !defined(__clang__) && \
1405
( \
1406
(defined(__INTEL_COMPILER) && !defined(_WIN32)) || \
1407
( \
1408
defined(__GNUC__) && ( \
1409
(defined(__ARM_ARCH) && __ARM_ARCH >= 7) || \
1410
( \
1411
defined(__mips__) && \
1412
(__mips <= 5 || __mips_isa_rev < 6) && \
1413
(!defined(__mips16) || defined(__mips_mips16e2)) \
1414
) \
1415
) \
1416
) \
1417
)
1418
# define XXH_FORCE_MEMORY_ACCESS 1
1419
# endif
1420
#endif
1421
1422
#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
1423
# if defined(__i386) || defined(__x86_64__) || defined(__aarch64__) \
1424
|| defined(_M_IX86) || defined(_M_X64) || defined(_M_ARM64) /* visual */
1425
# define XXH_FORCE_ALIGN_CHECK 0
1426
# else
1427
# define XXH_FORCE_ALIGN_CHECK 1
1428
# endif
1429
#endif
1430
1431
#ifndef XXH_NO_INLINE_HINTS
1432
# if defined(__OPTIMIZE_SIZE__) /* -Os, -Oz */ \
1433
|| defined(__NO_INLINE__) /* -O0, -fno-inline */
1434
# define XXH_NO_INLINE_HINTS 1
1435
# else
1436
# define XXH_NO_INLINE_HINTS 0
1437
# endif
1438
#endif
1439
1440
#ifndef XXH32_ENDJMP
1441
/* generally preferable for performance */
1442
# define XXH32_ENDJMP 0
1443
#endif
1444
1445
/*!
1446
* @defgroup impl Implementation
1447
* @{
1448
*/
1449
1450
1451
/* *************************************
1452
* Includes & Memory related functions
1453
***************************************/
1454
/* Modify the local functions below should you wish to use some other memory routines */
1455
/* for ZSTD_malloc(), ZSTD_free() */
1456
#define ZSTD_DEPS_NEED_MALLOC
1457
#include "zstd_deps.h" /* size_t, ZSTD_malloc, ZSTD_free, ZSTD_memcpy */
1458
static void* XXH_malloc(size_t s) { return ZSTD_malloc(s); }
1459
static void XXH_free (void* p) { ZSTD_free(p); }
1460
static void* XXH_memcpy(void* dest, const void* src, size_t size) { return ZSTD_memcpy(dest,src,size); }
1461
1462
1463
/* *************************************
1464
* Compiler Specific Options
1465
***************************************/
1466
#ifdef _MSC_VER /* Visual Studio warning fix */
1467
# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
1468
#endif
1469
1470
#if XXH_NO_INLINE_HINTS /* disable inlining hints */
1471
# if defined(__GNUC__) || defined(__clang__)
1472
# define XXH_FORCE_INLINE static __attribute__((unused))
1473
# else
1474
# define XXH_FORCE_INLINE static
1475
# endif
1476
# define XXH_NO_INLINE static
1477
/* enable inlining hints */
1478
#elif defined(__GNUC__) || defined(__clang__)
1479
# define XXH_FORCE_INLINE static __inline__ __attribute__((always_inline, unused))
1480
# define XXH_NO_INLINE static __attribute__((noinline))
1481
#elif defined(_MSC_VER) /* Visual Studio */
1482
# define XXH_FORCE_INLINE static __forceinline
1483
# define XXH_NO_INLINE static __declspec(noinline)
1484
#elif defined (__cplusplus) \
1485
|| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) /* C99 */
1486
# define XXH_FORCE_INLINE static inline
1487
# define XXH_NO_INLINE static
1488
#else
1489
# define XXH_FORCE_INLINE static
1490
# define XXH_NO_INLINE static
1491
#endif
1492
1493
1494
1495
/* *************************************
1496
* Debug
1497
***************************************/
1498
/*!
1499
* @ingroup tuning
1500
* @def XXH_DEBUGLEVEL
1501
* @brief Sets the debugging level.
1502
*
1503
* XXH_DEBUGLEVEL is expected to be defined externally, typically via the
1504
* compiler's command line options. The value must be a number.
1505
*/
1506
#ifndef XXH_DEBUGLEVEL
1507
# ifdef DEBUGLEVEL /* backwards compat */
1508
# define XXH_DEBUGLEVEL DEBUGLEVEL
1509
# else
1510
# define XXH_DEBUGLEVEL 0
1511
# endif
1512
#endif
1513
1514
#if (XXH_DEBUGLEVEL>=1)
1515
# include <assert.h> /* note: can still be disabled with NDEBUG */
1516
# define XXH_ASSERT(c) assert(c)
1517
#else
1518
# define XXH_ASSERT(c) ((void)0)
1519
#endif
1520
1521
/* note: use after variable declarations */
1522
#ifndef XXH_STATIC_ASSERT
1523
# if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) /* C11 */
1524
# include <assert.h>
1525
# define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { static_assert((c),m); } while(0)
1526
# elif defined(__cplusplus) && (__cplusplus >= 201103L) /* C++11 */
1527
# define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { static_assert((c),m); } while(0)
1528
# else
1529
# define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { struct xxh_sa { char x[(c) ? 1 : -1]; }; } while(0)
1530
# endif
1531
# define XXH_STATIC_ASSERT(c) XXH_STATIC_ASSERT_WITH_MESSAGE((c),#c)
1532
#endif
1533
1534
/*!
1535
* @internal
1536
* @def XXH_COMPILER_GUARD(var)
1537
* @brief Used to prevent unwanted optimizations for @p var.
1538
*
1539
* It uses an empty GCC inline assembly statement with a register constraint
1540
* which forces @p var into a general purpose register (eg eax, ebx, ecx
1541
* on x86) and marks it as modified.
1542
*
1543
* This is used in a few places to avoid unwanted autovectorization (e.g.
1544
* XXH32_round()). All vectorization we want is explicit via intrinsics,
1545
* and _usually_ isn't wanted elsewhere.
1546
*
1547
* We also use it to prevent unwanted constant folding for AArch64 in
1548
* XXH3_initCustomSecret_scalar().
1549
*/
1550
#if defined(__GNUC__) || defined(__clang__)
1551
# define XXH_COMPILER_GUARD(var) __asm__ __volatile__("" : "+r" (var))
1552
#else
1553
# define XXH_COMPILER_GUARD(var) ((void)0)
1554
#endif
1555
1556
/* *************************************
1557
* Basic Types
1558
***************************************/
1559
#if !defined (__VMS) \
1560
&& (defined (__cplusplus) \
1561
|| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
1562
# include <stdint.h>
1563
typedef uint8_t xxh_u8;
1564
#else
1565
typedef unsigned char xxh_u8;
1566
#endif
1567
typedef XXH32_hash_t xxh_u32;
1568
1569
#ifdef XXH_OLD_NAMES
1570
# define BYTE xxh_u8
1571
# define U8 xxh_u8
1572
# define U32 xxh_u32
1573
#endif
1574
1575
/* *** Memory access *** */
1576
1577
/*!
1578
* @internal
1579
* @fn xxh_u32 XXH_read32(const void* ptr)
1580
* @brief Reads an unaligned 32-bit integer from @p ptr in native endianness.
1581
*
1582
* Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1583
*
1584
* @param ptr The pointer to read from.
1585
* @return The 32-bit native endian integer from the bytes at @p ptr.
1586
*/
1587
1588
/*!
1589
* @internal
1590
* @fn xxh_u32 XXH_readLE32(const void* ptr)
1591
* @brief Reads an unaligned 32-bit little endian integer from @p ptr.
1592
*
1593
* Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1594
*
1595
* @param ptr The pointer to read from.
1596
* @return The 32-bit little endian integer from the bytes at @p ptr.
1597
*/
1598
1599
/*!
1600
* @internal
1601
* @fn xxh_u32 XXH_readBE32(const void* ptr)
1602
* @brief Reads an unaligned 32-bit big endian integer from @p ptr.
1603
*
1604
* Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1605
*
1606
* @param ptr The pointer to read from.
1607
* @return The 32-bit big endian integer from the bytes at @p ptr.
1608
*/
1609
1610
/*!
1611
* @internal
1612
* @fn xxh_u32 XXH_readLE32_align(const void* ptr, XXH_alignment align)
1613
* @brief Like @ref XXH_readLE32(), but has an option for aligned reads.
1614
*
1615
* Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1616
* Note that when @ref XXH_FORCE_ALIGN_CHECK == 0, the @p align parameter is
1617
* always @ref XXH_alignment::XXH_unaligned.
1618
*
1619
* @param ptr The pointer to read from.
1620
* @param align Whether @p ptr is aligned.
1621
* @pre
1622
* If @p align == @ref XXH_alignment::XXH_aligned, @p ptr must be 4 byte
1623
* aligned.
1624
* @return The 32-bit little endian integer from the bytes at @p ptr.
1625
*/
1626
1627
#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
1628
/*
1629
* Manual byteshift. Best for old compilers which don't inline memcpy.
1630
* We actually directly use XXH_readLE32 and XXH_readBE32.
1631
*/
1632
#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
1633
1634
/*
1635
* Force direct memory access. Only works on CPU which support unaligned memory
1636
* access in hardware.
1637
*/
1638
static xxh_u32 XXH_read32(const void* memPtr) { return *(const xxh_u32*) memPtr; }
1639
1640
#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
1641
1642
/*
1643
* __pack instructions are safer but compiler specific, hence potentially
1644
* problematic for some compilers.
1645
*
1646
* Currently only defined for GCC and ICC.
1647
*/
1648
#ifdef XXH_OLD_NAMES
1649
typedef union { xxh_u32 u32; } __attribute__((packed)) unalign;
1650
#endif
1651
static xxh_u32 XXH_read32(const void* ptr)
1652
{
1653
typedef union { xxh_u32 u32; } __attribute__((packed)) xxh_unalign;
1654
return ((const xxh_unalign*)ptr)->u32;
1655
}
1656
1657
#else
1658
1659
/*
1660
* Portable and safe solution. Generally efficient.
1661
* see: http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html
1662
*/
1663
static xxh_u32 XXH_read32(const void* memPtr)
1664
{
1665
xxh_u32 val;
1666
XXH_memcpy(&val, memPtr, sizeof(val));
1667
return val;
1668
}
1669
1670
#endif /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
1671
1672
1673
/* *** Endianness *** */
1674
1675
/*!
1676
* @ingroup tuning
1677
* @def XXH_CPU_LITTLE_ENDIAN
1678
* @brief Whether the target is little endian.
1679
*
1680
* Defined to 1 if the target is little endian, or 0 if it is big endian.
1681
* It can be defined externally, for example on the compiler command line.
1682
*
1683
* If it is not defined,
1684
* a runtime check (which is usually constant folded) is used instead.
1685
*
1686
* @note
1687
* This is not necessarily defined to an integer constant.
1688
*
1689
* @see XXH_isLittleEndian() for the runtime check.
1690
*/
1691
#ifndef XXH_CPU_LITTLE_ENDIAN
1692
/*
1693
* Try to detect endianness automatically, to avoid the nonstandard behavior
1694
* in `XXH_isLittleEndian()`
1695
*/
1696
# if defined(_WIN32) /* Windows is always little endian */ \
1697
|| defined(__LITTLE_ENDIAN__) \
1698
|| (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
1699
# define XXH_CPU_LITTLE_ENDIAN 1
1700
# elif defined(__BIG_ENDIAN__) \
1701
|| (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
1702
# define XXH_CPU_LITTLE_ENDIAN 0
1703
# else
1704
/*!
1705
* @internal
1706
* @brief Runtime check for @ref XXH_CPU_LITTLE_ENDIAN.
1707
*
1708
* Most compilers will constant fold this.
1709
*/
1710
static int XXH_isLittleEndian(void)
1711
{
1712
/*
1713
* Portable and well-defined behavior.
1714
* Don't use static: it is detrimental to performance.
1715
*/
1716
const union { xxh_u32 u; xxh_u8 c[4]; } one = { 1 };
1717
return one.c[0];
1718
}
1719
# define XXH_CPU_LITTLE_ENDIAN XXH_isLittleEndian()
1720
# endif
1721
#endif
1722
1723
1724
1725
1726
/* ****************************************
1727
* Compiler-specific Functions and Macros
1728
******************************************/
1729
#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
1730
1731
#ifdef __has_builtin
1732
# define XXH_HAS_BUILTIN(x) __has_builtin(x)
1733
#else
1734
# define XXH_HAS_BUILTIN(x) 0
1735
#endif
1736
1737
/*!
1738
* @internal
1739
* @def XXH_rotl32(x,r)
1740
* @brief 32-bit rotate left.
1741
*
1742
* @param x The 32-bit integer to be rotated.
1743
* @param r The number of bits to rotate.
1744
* @pre
1745
* @p r > 0 && @p r < 32
1746
* @note
1747
* @p x and @p r may be evaluated multiple times.
1748
* @return The rotated result.
1749
*/
1750
#if !defined(NO_CLANG_BUILTIN) && XXH_HAS_BUILTIN(__builtin_rotateleft32) \
1751
&& XXH_HAS_BUILTIN(__builtin_rotateleft64)
1752
# define XXH_rotl32 __builtin_rotateleft32
1753
# define XXH_rotl64 __builtin_rotateleft64
1754
/* Note: although _rotl exists for minGW (GCC under windows), performance seems poor */
1755
#elif defined(_MSC_VER)
1756
# define XXH_rotl32(x,r) _rotl(x,r)
1757
# define XXH_rotl64(x,r) _rotl64(x,r)
1758
#else
1759
# define XXH_rotl32(x,r) (((x) << (r)) | ((x) >> (32 - (r))))
1760
# define XXH_rotl64(x,r) (((x) << (r)) | ((x) >> (64 - (r))))
1761
#endif
1762
1763
/*!
1764
* @internal
1765
* @fn xxh_u32 XXH_swap32(xxh_u32 x)
1766
* @brief A 32-bit byteswap.
1767
*
1768
* @param x The 32-bit integer to byteswap.
1769
* @return @p x, byteswapped.
1770
*/
1771
#if defined(_MSC_VER) /* Visual Studio */
1772
# define XXH_swap32 _byteswap_ulong
1773
#elif XXH_GCC_VERSION >= 403
1774
# define XXH_swap32 __builtin_bswap32
1775
#else
1776
static xxh_u32 XXH_swap32 (xxh_u32 x)
1777
{
1778
return ((x << 24) & 0xff000000 ) |
1779
((x << 8) & 0x00ff0000 ) |
1780
((x >> 8) & 0x0000ff00 ) |
1781
((x >> 24) & 0x000000ff );
1782
}
1783
#endif
1784
1785
1786
/* ***************************
1787
* Memory reads
1788
*****************************/
1789
1790
/*!
1791
* @internal
1792
* @brief Enum to indicate whether a pointer is aligned.
1793
*/
1794
typedef enum {
1795
XXH_aligned, /*!< Aligned */
1796
XXH_unaligned /*!< Possibly unaligned */
1797
} XXH_alignment;
1798
1799
/*
1800
* XXH_FORCE_MEMORY_ACCESS==3 is an endian-independent byteshift load.
1801
*
1802
* This is ideal for older compilers which don't inline memcpy.
1803
*/
1804
#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
1805
1806
XXH_FORCE_INLINE xxh_u32 XXH_readLE32(const void* memPtr)
1807
{
1808
const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
1809
return bytePtr[0]
1810
| ((xxh_u32)bytePtr[1] << 8)
1811
| ((xxh_u32)bytePtr[2] << 16)
1812
| ((xxh_u32)bytePtr[3] << 24);
1813
}
1814
1815
XXH_FORCE_INLINE xxh_u32 XXH_readBE32(const void* memPtr)
1816
{
1817
const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
1818
return bytePtr[3]
1819
| ((xxh_u32)bytePtr[2] << 8)
1820
| ((xxh_u32)bytePtr[1] << 16)
1821
| ((xxh_u32)bytePtr[0] << 24);
1822
}
1823
1824
#else
1825
XXH_FORCE_INLINE xxh_u32 XXH_readLE32(const void* ptr)
1826
{
1827
return XXH_CPU_LITTLE_ENDIAN ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
1828
}
1829
1830
static xxh_u32 XXH_readBE32(const void* ptr)
1831
{
1832
return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
1833
}
1834
#endif
1835
1836
XXH_FORCE_INLINE xxh_u32
1837
XXH_readLE32_align(const void* ptr, XXH_alignment align)
1838
{
1839
if (align==XXH_unaligned) {
1840
return XXH_readLE32(ptr);
1841
} else {
1842
return XXH_CPU_LITTLE_ENDIAN ? *(const xxh_u32*)ptr : XXH_swap32(*(const xxh_u32*)ptr);
1843
}
1844
}
1845
1846
1847
/* *************************************
1848
* Misc
1849
***************************************/
1850
/*! @ingroup public */
1851
XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
1852
1853
1854
/* *******************************************************************
1855
* 32-bit hash functions
1856
*********************************************************************/
1857
/*!
1858
* @}
1859
* @defgroup xxh32_impl XXH32 implementation
1860
* @ingroup impl
1861
* @{
1862
*/
1863
/* #define instead of static const, to be used as initializers */
1864
#define XXH_PRIME32_1 0x9E3779B1U /*!< 0b10011110001101110111100110110001 */
1865
#define XXH_PRIME32_2 0x85EBCA77U /*!< 0b10000101111010111100101001110111 */
1866
#define XXH_PRIME32_3 0xC2B2AE3DU /*!< 0b11000010101100101010111000111101 */
1867
#define XXH_PRIME32_4 0x27D4EB2FU /*!< 0b00100111110101001110101100101111 */
1868
#define XXH_PRIME32_5 0x165667B1U /*!< 0b00010110010101100110011110110001 */
1869
1870
#ifdef XXH_OLD_NAMES
1871
# define PRIME32_1 XXH_PRIME32_1
1872
# define PRIME32_2 XXH_PRIME32_2
1873
# define PRIME32_3 XXH_PRIME32_3
1874
# define PRIME32_4 XXH_PRIME32_4
1875
# define PRIME32_5 XXH_PRIME32_5
1876
#endif
1877
1878
/*!
1879
* @internal
1880
* @brief Normal stripe processing routine.
1881
*
1882
* This shuffles the bits so that any bit from @p input impacts several bits in
1883
* @p acc.
1884
*
1885
* @param acc The accumulator lane.
1886
* @param input The stripe of input to mix.
1887
* @return The mixed accumulator lane.
1888
*/
1889
static xxh_u32 XXH32_round(xxh_u32 acc, xxh_u32 input)
1890
{
1891
acc += input * XXH_PRIME32_2;
1892
acc = XXH_rotl32(acc, 13);
1893
acc *= XXH_PRIME32_1;
1894
#if (defined(__SSE4_1__) || defined(__aarch64__)) && !defined(XXH_ENABLE_AUTOVECTORIZE)
1895
/*
1896
* UGLY HACK:
1897
* A compiler fence is the only thing that prevents GCC and Clang from
1898
* autovectorizing the XXH32 loop (pragmas and attributes don't work for some
1899
* reason) without globally disabling SSE4.1.
1900
*
1901
* The reason we want to avoid vectorization is because despite working on
1902
* 4 integers at a time, there are multiple factors slowing XXH32 down on
1903
* SSE4:
1904
* - There's a ridiculous amount of lag from pmulld (10 cycles of latency on
1905
* newer chips!) making it slightly slower to multiply four integers at
1906
* once compared to four integers independently. Even when pmulld was
1907
* fastest, Sandy/Ivy Bridge, it is still not worth it to go into SSE
1908
* just to multiply unless doing a long operation.
1909
*
1910
* - Four instructions are required to rotate,
1911
* movqda tmp, v // not required with VEX encoding
1912
* pslld tmp, 13 // tmp <<= 13
1913
* psrld v, 19 // x >>= 19
1914
* por v, tmp // x |= tmp
1915
* compared to one for scalar:
1916
* roll v, 13 // reliably fast across the board
1917
* shldl v, v, 13 // Sandy Bridge and later prefer this for some reason
1918
*
1919
* - Instruction level parallelism is actually more beneficial here because
1920
* the SIMD actually serializes this operation: While v1 is rotating, v2
1921
* can load data, while v3 can multiply. SSE forces them to operate
1922
* together.
1923
*
1924
* This is also enabled on AArch64, as Clang autovectorizes it incorrectly
1925
* and it is pointless writing a NEON implementation that is basically the
1926
* same speed as scalar for XXH32.
1927
*/
1928
XXH_COMPILER_GUARD(acc);
1929
#endif
1930
return acc;
1931
}
1932
1933
/*!
1934
* @internal
1935
* @brief Mixes all bits to finalize the hash.
1936
*
1937
* The final mix ensures that all input bits have a chance to impact any bit in
1938
* the output digest, resulting in an unbiased distribution.
1939
*
1940
* @param h32 The hash to avalanche.
1941
* @return The avalanched hash.
1942
*/
1943
static xxh_u32 XXH32_avalanche(xxh_u32 h32)
1944
{
1945
h32 ^= h32 >> 15;
1946
h32 *= XXH_PRIME32_2;
1947
h32 ^= h32 >> 13;
1948
h32 *= XXH_PRIME32_3;
1949
h32 ^= h32 >> 16;
1950
return(h32);
1951
}
1952
1953
#define XXH_get32bits(p) XXH_readLE32_align(p, align)
1954
1955
/*!
1956
* @internal
1957
* @brief Processes the last 0-15 bytes of @p ptr.
1958
*
1959
* There may be up to 15 bytes remaining to consume from the input.
1960
* This final stage will digest them to ensure that all input bytes are present
1961
* in the final mix.
1962
*
1963
* @param h32 The hash to finalize.
1964
* @param ptr The pointer to the remaining input.
1965
* @param len The remaining length, modulo 16.
1966
* @param align Whether @p ptr is aligned.
1967
* @return The finalized hash.
1968
*/
1969
static xxh_u32
1970
XXH32_finalize(xxh_u32 h32, const xxh_u8* ptr, size_t len, XXH_alignment align)
1971
{
1972
#define XXH_PROCESS1 do { \
1973
h32 += (*ptr++) * XXH_PRIME32_5; \
1974
h32 = XXH_rotl32(h32, 11) * XXH_PRIME32_1; \
1975
} while (0)
1976
1977
#define XXH_PROCESS4 do { \
1978
h32 += XXH_get32bits(ptr) * XXH_PRIME32_3; \
1979
ptr += 4; \
1980
h32 = XXH_rotl32(h32, 17) * XXH_PRIME32_4; \
1981
} while (0)
1982
1983
if (ptr==NULL) XXH_ASSERT(len == 0);
1984
1985
/* Compact rerolled version; generally faster */
1986
if (!XXH32_ENDJMP) {
1987
len &= 15;
1988
while (len >= 4) {
1989
XXH_PROCESS4;
1990
len -= 4;
1991
}
1992
while (len > 0) {
1993
XXH_PROCESS1;
1994
--len;
1995
}
1996
return XXH32_avalanche(h32);
1997
} else {
1998
switch(len&15) /* or switch(bEnd - p) */ {
1999
case 12: XXH_PROCESS4;
2000
XXH_FALLTHROUGH;
2001
case 8: XXH_PROCESS4;
2002
XXH_FALLTHROUGH;
2003
case 4: XXH_PROCESS4;
2004
return XXH32_avalanche(h32);
2005
2006
case 13: XXH_PROCESS4;
2007
XXH_FALLTHROUGH;
2008
case 9: XXH_PROCESS4;
2009
XXH_FALLTHROUGH;
2010
case 5: XXH_PROCESS4;
2011
XXH_PROCESS1;
2012
return XXH32_avalanche(h32);
2013
2014
case 14: XXH_PROCESS4;
2015
XXH_FALLTHROUGH;
2016
case 10: XXH_PROCESS4;
2017
XXH_FALLTHROUGH;
2018
case 6: XXH_PROCESS4;
2019
XXH_PROCESS1;
2020
XXH_PROCESS1;
2021
return XXH32_avalanche(h32);
2022
2023
case 15: XXH_PROCESS4;
2024
XXH_FALLTHROUGH;
2025
case 11: XXH_PROCESS4;
2026
XXH_FALLTHROUGH;
2027
case 7: XXH_PROCESS4;
2028
XXH_FALLTHROUGH;
2029
case 3: XXH_PROCESS1;
2030
XXH_FALLTHROUGH;
2031
case 2: XXH_PROCESS1;
2032
XXH_FALLTHROUGH;
2033
case 1: XXH_PROCESS1;
2034
XXH_FALLTHROUGH;
2035
case 0: return XXH32_avalanche(h32);
2036
}
2037
XXH_ASSERT(0);
2038
return h32; /* reaching this point is deemed impossible */
2039
}
2040
}
2041
2042
#ifdef XXH_OLD_NAMES
2043
# define PROCESS1 XXH_PROCESS1
2044
# define PROCESS4 XXH_PROCESS4
2045
#else
2046
# undef XXH_PROCESS1
2047
# undef XXH_PROCESS4
2048
#endif
2049
2050
/*!
2051
* @internal
2052
* @brief The implementation for @ref XXH32().
2053
*
2054
* @param input , len , seed Directly passed from @ref XXH32().
2055
* @param align Whether @p input is aligned.
2056
* @return The calculated hash.
2057
*/
2058
XXH_FORCE_INLINE xxh_u32
2059
XXH32_endian_align(const xxh_u8* input, size_t len, xxh_u32 seed, XXH_alignment align)
2060
{
2061
xxh_u32 h32;
2062
2063
if (input==NULL) XXH_ASSERT(len == 0);
2064
2065
if (len>=16) {
2066
const xxh_u8* const bEnd = input + len;
2067
const xxh_u8* const limit = bEnd - 15;
2068
xxh_u32 v1 = seed + XXH_PRIME32_1 + XXH_PRIME32_2;
2069
xxh_u32 v2 = seed + XXH_PRIME32_2;
2070
xxh_u32 v3 = seed + 0;
2071
xxh_u32 v4 = seed - XXH_PRIME32_1;
2072
2073
do {
2074
v1 = XXH32_round(v1, XXH_get32bits(input)); input += 4;
2075
v2 = XXH32_round(v2, XXH_get32bits(input)); input += 4;
2076
v3 = XXH32_round(v3, XXH_get32bits(input)); input += 4;
2077
v4 = XXH32_round(v4, XXH_get32bits(input)); input += 4;
2078
} while (input < limit);
2079
2080
h32 = XXH_rotl32(v1, 1) + XXH_rotl32(v2, 7)
2081
+ XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
2082
} else {
2083
h32 = seed + XXH_PRIME32_5;
2084
}
2085
2086
h32 += (xxh_u32)len;
2087
2088
return XXH32_finalize(h32, input, len&15, align);
2089
}
2090
2091
/*! @ingroup xxh32_family */
2092
XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t len, XXH32_hash_t seed)
2093
{
2094
#if 0
2095
/* Simple version, good for code maintenance, but unfortunately slow for small inputs */
2096
XXH32_state_t state;
2097
XXH32_reset(&state, seed);
2098
XXH32_update(&state, (const xxh_u8*)input, len);
2099
return XXH32_digest(&state);
2100
#else
2101
if (XXH_FORCE_ALIGN_CHECK) {
2102
if ((((size_t)input) & 3) == 0) { /* Input is 4-bytes aligned, leverage the speed benefit */
2103
return XXH32_endian_align((const xxh_u8*)input, len, seed, XXH_aligned);
2104
} }
2105
2106
return XXH32_endian_align((const xxh_u8*)input, len, seed, XXH_unaligned);
2107
#endif
2108
}
2109
2110
2111
2112
/******* Hash streaming *******/
2113
/*!
2114
* @ingroup xxh32_family
2115
*/
2116
XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
2117
{
2118
return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
2119
}
2120
/*! @ingroup xxh32_family */
2121
XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
2122
{
2123
XXH_free(statePtr);
2124
return XXH_OK;
2125
}
2126
2127
/*! @ingroup xxh32_family */
2128
XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState)
2129
{
2130
XXH_memcpy(dstState, srcState, sizeof(*dstState));
2131
}
2132
2133
/*! @ingroup xxh32_family */
2134
XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, XXH32_hash_t seed)
2135
{
2136
XXH_ASSERT(statePtr != NULL);
2137
memset(statePtr, 0, sizeof(*statePtr));
2138
statePtr->v[0] = seed + XXH_PRIME32_1 + XXH_PRIME32_2;
2139
statePtr->v[1] = seed + XXH_PRIME32_2;
2140
statePtr->v[2] = seed + 0;
2141
statePtr->v[3] = seed - XXH_PRIME32_1;
2142
return XXH_OK;
2143
}
2144
2145
2146
/*! @ingroup xxh32_family */
2147
XXH_PUBLIC_API XXH_errorcode
2148
XXH32_update(XXH32_state_t* state, const void* input, size_t len)
2149
{
2150
if (input==NULL) {
2151
XXH_ASSERT(len == 0);
2152
return XXH_OK;
2153
}
2154
2155
{ const xxh_u8* p = (const xxh_u8*)input;
2156
const xxh_u8* const bEnd = p + len;
2157
2158
state->total_len_32 += (XXH32_hash_t)len;
2159
state->large_len |= (XXH32_hash_t)((len>=16) | (state->total_len_32>=16));
2160
2161
if (state->memsize + len < 16) { /* fill in tmp buffer */
2162
XXH_memcpy((xxh_u8*)(state->mem32) + state->memsize, input, len);
2163
state->memsize += (XXH32_hash_t)len;
2164
return XXH_OK;
2165
}
2166
2167
if (state->memsize) { /* some data left from previous update */
2168
XXH_memcpy((xxh_u8*)(state->mem32) + state->memsize, input, 16-state->memsize);
2169
{ const xxh_u32* p32 = state->mem32;
2170
state->v[0] = XXH32_round(state->v[0], XXH_readLE32(p32)); p32++;
2171
state->v[1] = XXH32_round(state->v[1], XXH_readLE32(p32)); p32++;
2172
state->v[2] = XXH32_round(state->v[2], XXH_readLE32(p32)); p32++;
2173
state->v[3] = XXH32_round(state->v[3], XXH_readLE32(p32));
2174
}
2175
p += 16-state->memsize;
2176
state->memsize = 0;
2177
}
2178
2179
if (p <= bEnd-16) {
2180
const xxh_u8* const limit = bEnd - 16;
2181
2182
do {
2183
state->v[0] = XXH32_round(state->v[0], XXH_readLE32(p)); p+=4;
2184
state->v[1] = XXH32_round(state->v[1], XXH_readLE32(p)); p+=4;
2185
state->v[2] = XXH32_round(state->v[2], XXH_readLE32(p)); p+=4;
2186
state->v[3] = XXH32_round(state->v[3], XXH_readLE32(p)); p+=4;
2187
} while (p<=limit);
2188
2189
}
2190
2191
if (p < bEnd) {
2192
XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
2193
state->memsize = (unsigned)(bEnd-p);
2194
}
2195
}
2196
2197
return XXH_OK;
2198
}
2199
2200
2201
/*! @ingroup xxh32_family */
2202
XXH_PUBLIC_API XXH32_hash_t XXH32_digest(const XXH32_state_t* state)
2203
{
2204
xxh_u32 h32;
2205
2206
if (state->large_len) {
2207
h32 = XXH_rotl32(state->v[0], 1)
2208
+ XXH_rotl32(state->v[1], 7)
2209
+ XXH_rotl32(state->v[2], 12)
2210
+ XXH_rotl32(state->v[3], 18);
2211
} else {
2212
h32 = state->v[2] /* == seed */ + XXH_PRIME32_5;
2213
}
2214
2215
h32 += state->total_len_32;
2216
2217
return XXH32_finalize(h32, (const xxh_u8*)state->mem32, state->memsize, XXH_aligned);
2218
}
2219
2220
2221
/******* Canonical representation *******/
2222
2223
/*!
2224
* @ingroup xxh32_family
2225
* The default return values from XXH functions are unsigned 32 and 64 bit
2226
* integers.
2227
*
2228
* The canonical representation uses big endian convention, the same convention
2229
* as human-readable numbers (large digits first).
2230
*
2231
* This way, hash values can be written into a file or buffer, remaining
2232
* comparable across different systems.
2233
*
2234
* The following functions allow transformation of hash values to and from their
2235
* canonical format.
2236
*/
2237
XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
2238
{
2239
/* XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t)); */
2240
if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
2241
XXH_memcpy(dst, &hash, sizeof(*dst));
2242
}
2243
/*! @ingroup xxh32_family */
2244
XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
2245
{
2246
return XXH_readBE32(src);
2247
}
2248
2249
2250
#ifndef XXH_NO_LONG_LONG
2251
2252
/* *******************************************************************
2253
* 64-bit hash functions
2254
*********************************************************************/
2255
/*!
2256
* @}
2257
* @ingroup impl
2258
* @{
2259
*/
2260
/******* Memory access *******/
2261
2262
typedef XXH64_hash_t xxh_u64;
2263
2264
#ifdef XXH_OLD_NAMES
2265
# define U64 xxh_u64
2266
#endif
2267
2268
#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
2269
/*
2270
* Manual byteshift. Best for old compilers which don't inline memcpy.
2271
* We actually directly use XXH_readLE64 and XXH_readBE64.
2272
*/
2273
#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
2274
2275
/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
2276
static xxh_u64 XXH_read64(const void* memPtr)
2277
{
2278
return *(const xxh_u64*) memPtr;
2279
}
2280
2281
#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
2282
2283
/*
2284
* __pack instructions are safer, but compiler specific, hence potentially
2285
* problematic for some compilers.
2286
*
2287
* Currently only defined for GCC and ICC.
2288
*/
2289
#ifdef XXH_OLD_NAMES
2290
typedef union { xxh_u32 u32; xxh_u64 u64; } __attribute__((packed)) unalign64;
2291
#endif
2292
static xxh_u64 XXH_read64(const void* ptr)
2293
{
2294
typedef union { xxh_u32 u32; xxh_u64 u64; } __attribute__((packed)) xxh_unalign64;
2295
return ((const xxh_unalign64*)ptr)->u64;
2296
}
2297
2298
#else
2299
2300
/*
2301
* Portable and safe solution. Generally efficient.
2302
* see: http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html
2303
*/
2304
static xxh_u64 XXH_read64(const void* memPtr)
2305
{
2306
xxh_u64 val;
2307
XXH_memcpy(&val, memPtr, sizeof(val));
2308
return val;
2309
}
2310
2311
#endif /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
2312
2313
#if defined(_MSC_VER) /* Visual Studio */
2314
# define XXH_swap64 _byteswap_uint64
2315
#elif XXH_GCC_VERSION >= 403
2316
# define XXH_swap64 __builtin_bswap64
2317
#else
2318
static xxh_u64 XXH_swap64(xxh_u64 x)
2319
{
2320
return ((x << 56) & 0xff00000000000000ULL) |
2321
((x << 40) & 0x00ff000000000000ULL) |
2322
((x << 24) & 0x0000ff0000000000ULL) |
2323
((x << 8) & 0x000000ff00000000ULL) |
2324
((x >> 8) & 0x00000000ff000000ULL) |
2325
((x >> 24) & 0x0000000000ff0000ULL) |
2326
((x >> 40) & 0x000000000000ff00ULL) |
2327
((x >> 56) & 0x00000000000000ffULL);
2328
}
2329
#endif
2330
2331
2332
/* XXH_FORCE_MEMORY_ACCESS==3 is an endian-independent byteshift load. */
2333
#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
2334
2335
XXH_FORCE_INLINE xxh_u64 XXH_readLE64(const void* memPtr)
2336
{
2337
const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
2338
return bytePtr[0]
2339
| ((xxh_u64)bytePtr[1] << 8)
2340
| ((xxh_u64)bytePtr[2] << 16)
2341
| ((xxh_u64)bytePtr[3] << 24)
2342
| ((xxh_u64)bytePtr[4] << 32)
2343
| ((xxh_u64)bytePtr[5] << 40)
2344
| ((xxh_u64)bytePtr[6] << 48)
2345
| ((xxh_u64)bytePtr[7] << 56);
2346
}
2347
2348
XXH_FORCE_INLINE xxh_u64 XXH_readBE64(const void* memPtr)
2349
{
2350
const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
2351
return bytePtr[7]
2352
| ((xxh_u64)bytePtr[6] << 8)
2353
| ((xxh_u64)bytePtr[5] << 16)
2354
| ((xxh_u64)bytePtr[4] << 24)
2355
| ((xxh_u64)bytePtr[3] << 32)
2356
| ((xxh_u64)bytePtr[2] << 40)
2357
| ((xxh_u64)bytePtr[1] << 48)
2358
| ((xxh_u64)bytePtr[0] << 56);
2359
}
2360
2361
#else
2362
XXH_FORCE_INLINE xxh_u64 XXH_readLE64(const void* ptr)
2363
{
2364
return XXH_CPU_LITTLE_ENDIAN ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
2365
}
2366
2367
static xxh_u64 XXH_readBE64(const void* ptr)
2368
{
2369
return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
2370
}
2371
#endif
2372
2373
XXH_FORCE_INLINE xxh_u64
2374
XXH_readLE64_align(const void* ptr, XXH_alignment align)
2375
{
2376
if (align==XXH_unaligned)
2377
return XXH_readLE64(ptr);
2378
else
2379
return XXH_CPU_LITTLE_ENDIAN ? *(const xxh_u64*)ptr : XXH_swap64(*(const xxh_u64*)ptr);
2380
}
2381
2382
2383
/******* xxh64 *******/
2384
/*!
2385
* @}
2386
* @defgroup xxh64_impl XXH64 implementation
2387
* @ingroup impl
2388
* @{
2389
*/
2390
/* #define rather that static const, to be used as initializers */
2391
#define XXH_PRIME64_1 0x9E3779B185EBCA87ULL /*!< 0b1001111000110111011110011011000110000101111010111100101010000111 */
2392
#define XXH_PRIME64_2 0xC2B2AE3D27D4EB4FULL /*!< 0b1100001010110010101011100011110100100111110101001110101101001111 */
2393
#define XXH_PRIME64_3 0x165667B19E3779F9ULL /*!< 0b0001011001010110011001111011000110011110001101110111100111111001 */
2394
#define XXH_PRIME64_4 0x85EBCA77C2B2AE63ULL /*!< 0b1000010111101011110010100111011111000010101100101010111001100011 */
2395
#define XXH_PRIME64_5 0x27D4EB2F165667C5ULL /*!< 0b0010011111010100111010110010111100010110010101100110011111000101 */
2396
2397
#ifdef XXH_OLD_NAMES
2398
# define PRIME64_1 XXH_PRIME64_1
2399
# define PRIME64_2 XXH_PRIME64_2
2400
# define PRIME64_3 XXH_PRIME64_3
2401
# define PRIME64_4 XXH_PRIME64_4
2402
# define PRIME64_5 XXH_PRIME64_5
2403
#endif
2404
2405
static xxh_u64 XXH64_round(xxh_u64 acc, xxh_u64 input)
2406
{
2407
acc += input * XXH_PRIME64_2;
2408
acc = XXH_rotl64(acc, 31);
2409
acc *= XXH_PRIME64_1;
2410
return acc;
2411
}
2412
2413
static xxh_u64 XXH64_mergeRound(xxh_u64 acc, xxh_u64 val)
2414
{
2415
val = XXH64_round(0, val);
2416
acc ^= val;
2417
acc = acc * XXH_PRIME64_1 + XXH_PRIME64_4;
2418
return acc;
2419
}
2420
2421
static xxh_u64 XXH64_avalanche(xxh_u64 h64)
2422
{
2423
h64 ^= h64 >> 33;
2424
h64 *= XXH_PRIME64_2;
2425
h64 ^= h64 >> 29;
2426
h64 *= XXH_PRIME64_3;
2427
h64 ^= h64 >> 32;
2428
return h64;
2429
}
2430
2431
2432
#define XXH_get64bits(p) XXH_readLE64_align(p, align)
2433
2434
static xxh_u64
2435
XXH64_finalize(xxh_u64 h64, const xxh_u8* ptr, size_t len, XXH_alignment align)
2436
{
2437
if (ptr==NULL) XXH_ASSERT(len == 0);
2438
len &= 31;
2439
while (len >= 8) {
2440
xxh_u64 const k1 = XXH64_round(0, XXH_get64bits(ptr));
2441
ptr += 8;
2442
h64 ^= k1;
2443
h64 = XXH_rotl64(h64,27) * XXH_PRIME64_1 + XXH_PRIME64_4;
2444
len -= 8;
2445
}
2446
if (len >= 4) {
2447
h64 ^= (xxh_u64)(XXH_get32bits(ptr)) * XXH_PRIME64_1;
2448
ptr += 4;
2449
h64 = XXH_rotl64(h64, 23) * XXH_PRIME64_2 + XXH_PRIME64_3;
2450
len -= 4;
2451
}
2452
while (len > 0) {
2453
h64 ^= (*ptr++) * XXH_PRIME64_5;
2454
h64 = XXH_rotl64(h64, 11) * XXH_PRIME64_1;
2455
--len;
2456
}
2457
return XXH64_avalanche(h64);
2458
}
2459
2460
#ifdef XXH_OLD_NAMES
2461
# define PROCESS1_64 XXH_PROCESS1_64
2462
# define PROCESS4_64 XXH_PROCESS4_64
2463
# define PROCESS8_64 XXH_PROCESS8_64
2464
#else
2465
# undef XXH_PROCESS1_64
2466
# undef XXH_PROCESS4_64
2467
# undef XXH_PROCESS8_64
2468
#endif
2469
2470
XXH_FORCE_INLINE xxh_u64
2471
XXH64_endian_align(const xxh_u8* input, size_t len, xxh_u64 seed, XXH_alignment align)
2472
{
2473
xxh_u64 h64;
2474
if (input==NULL) XXH_ASSERT(len == 0);
2475
2476
if (len>=32) {
2477
const xxh_u8* const bEnd = input + len;
2478
const xxh_u8* const limit = bEnd - 31;
2479
xxh_u64 v1 = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
2480
xxh_u64 v2 = seed + XXH_PRIME64_2;
2481
xxh_u64 v3 = seed + 0;
2482
xxh_u64 v4 = seed - XXH_PRIME64_1;
2483
2484
do {
2485
v1 = XXH64_round(v1, XXH_get64bits(input)); input+=8;
2486
v2 = XXH64_round(v2, XXH_get64bits(input)); input+=8;
2487
v3 = XXH64_round(v3, XXH_get64bits(input)); input+=8;
2488
v4 = XXH64_round(v4, XXH_get64bits(input)); input+=8;
2489
} while (input<limit);
2490
2491
h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
2492
h64 = XXH64_mergeRound(h64, v1);
2493
h64 = XXH64_mergeRound(h64, v2);
2494
h64 = XXH64_mergeRound(h64, v3);
2495
h64 = XXH64_mergeRound(h64, v4);
2496
2497
} else {
2498
h64 = seed + XXH_PRIME64_5;
2499
}
2500
2501
h64 += (xxh_u64) len;
2502
2503
return XXH64_finalize(h64, input, len, align);
2504
}
2505
2506
2507
/*! @ingroup xxh64_family */
2508
XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t len, XXH64_hash_t seed)
2509
{
2510
#if 0
2511
/* Simple version, good for code maintenance, but unfortunately slow for small inputs */
2512
XXH64_state_t state;
2513
XXH64_reset(&state, seed);
2514
XXH64_update(&state, (const xxh_u8*)input, len);
2515
return XXH64_digest(&state);
2516
#else
2517
if (XXH_FORCE_ALIGN_CHECK) {
2518
if ((((size_t)input) & 7)==0) { /* Input is aligned, let's leverage the speed advantage */
2519
return XXH64_endian_align((const xxh_u8*)input, len, seed, XXH_aligned);
2520
} }
2521
2522
return XXH64_endian_align((const xxh_u8*)input, len, seed, XXH_unaligned);
2523
2524
#endif
2525
}
2526
2527
/******* Hash Streaming *******/
2528
2529
/*! @ingroup xxh64_family*/
2530
XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
2531
{
2532
return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
2533
}
2534
/*! @ingroup xxh64_family */
2535
XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
2536
{
2537
XXH_free(statePtr);
2538
return XXH_OK;
2539
}
2540
2541
/*! @ingroup xxh64_family */
2542
XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState)
2543
{
2544
XXH_memcpy(dstState, srcState, sizeof(*dstState));
2545
}
2546
2547
/*! @ingroup xxh64_family */
2548
XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, XXH64_hash_t seed)
2549
{
2550
XXH_ASSERT(statePtr != NULL);
2551
memset(statePtr, 0, sizeof(*statePtr));
2552
statePtr->v[0] = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
2553
statePtr->v[1] = seed + XXH_PRIME64_2;
2554
statePtr->v[2] = seed + 0;
2555
statePtr->v[3] = seed - XXH_PRIME64_1;
2556
return XXH_OK;
2557
}
2558
2559
/*! @ingroup xxh64_family */
2560
XXH_PUBLIC_API XXH_errorcode
2561
XXH64_update (XXH64_state_t* state, const void* input, size_t len)
2562
{
2563
if (input==NULL) {
2564
XXH_ASSERT(len == 0);
2565
return XXH_OK;
2566
}
2567
2568
{ const xxh_u8* p = (const xxh_u8*)input;
2569
const xxh_u8* const bEnd = p + len;
2570
2571
state->total_len += len;
2572
2573
if (state->memsize + len < 32) { /* fill in tmp buffer */
2574
XXH_memcpy(((xxh_u8*)state->mem64) + state->memsize, input, len);
2575
state->memsize += (xxh_u32)len;
2576
return XXH_OK;
2577
}
2578
2579
if (state->memsize) { /* tmp buffer is full */
2580
XXH_memcpy(((xxh_u8*)state->mem64) + state->memsize, input, 32-state->memsize);
2581
state->v[0] = XXH64_round(state->v[0], XXH_readLE64(state->mem64+0));
2582
state->v[1] = XXH64_round(state->v[1], XXH_readLE64(state->mem64+1));
2583
state->v[2] = XXH64_round(state->v[2], XXH_readLE64(state->mem64+2));
2584
state->v[3] = XXH64_round(state->v[3], XXH_readLE64(state->mem64+3));
2585
p += 32 - state->memsize;
2586
state->memsize = 0;
2587
}
2588
2589
if (p+32 <= bEnd) {
2590
const xxh_u8* const limit = bEnd - 32;
2591
2592
do {
2593
state->v[0] = XXH64_round(state->v[0], XXH_readLE64(p)); p+=8;
2594
state->v[1] = XXH64_round(state->v[1], XXH_readLE64(p)); p+=8;
2595
state->v[2] = XXH64_round(state->v[2], XXH_readLE64(p)); p+=8;
2596
state->v[3] = XXH64_round(state->v[3], XXH_readLE64(p)); p+=8;
2597
} while (p<=limit);
2598
2599
}
2600
2601
if (p < bEnd) {
2602
XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
2603
state->memsize = (unsigned)(bEnd-p);
2604
}
2605
}
2606
2607
return XXH_OK;
2608
}
2609
2610
2611
/*! @ingroup xxh64_family */
2612
XXH_PUBLIC_API XXH64_hash_t XXH64_digest(const XXH64_state_t* state)
2613
{
2614
xxh_u64 h64;
2615
2616
if (state->total_len >= 32) {
2617
h64 = XXH_rotl64(state->v[0], 1) + XXH_rotl64(state->v[1], 7) + XXH_rotl64(state->v[2], 12) + XXH_rotl64(state->v[3], 18);
2618
h64 = XXH64_mergeRound(h64, state->v[0]);
2619
h64 = XXH64_mergeRound(h64, state->v[1]);
2620
h64 = XXH64_mergeRound(h64, state->v[2]);
2621
h64 = XXH64_mergeRound(h64, state->v[3]);
2622
} else {
2623
h64 = state->v[2] /*seed*/ + XXH_PRIME64_5;
2624
}
2625
2626
h64 += (xxh_u64) state->total_len;
2627
2628
return XXH64_finalize(h64, (const xxh_u8*)state->mem64, (size_t)state->total_len, XXH_aligned);
2629
}
2630
2631
2632
/******* Canonical representation *******/
2633
2634
/*! @ingroup xxh64_family */
2635
XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
2636
{
2637
/* XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t)); */
2638
if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
2639
XXH_memcpy(dst, &hash, sizeof(*dst));
2640
}
2641
2642
/*! @ingroup xxh64_family */
2643
XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
2644
{
2645
return XXH_readBE64(src);
2646
}
2647
2648
#ifndef XXH_NO_XXH3
2649
2650
/* *********************************************************************
2651
* XXH3
2652
* New generation hash designed for speed on small keys and vectorization
2653
************************************************************************ */
2654
/*!
2655
* @}
2656
* @defgroup xxh3_impl XXH3 implementation
2657
* @ingroup impl
2658
* @{
2659
*/
2660
2661
/* === Compiler specifics === */
2662
2663
#if ((defined(sun) || defined(__sun)) && __cplusplus) /* Solaris includes __STDC_VERSION__ with C++. Tested with GCC 5.5 */
2664
# define XXH_RESTRICT /* disable */
2665
#elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* >= C99 */
2666
# define XXH_RESTRICT restrict
2667
#else
2668
/* Note: it might be useful to define __restrict or __restrict__ for some C++ compilers */
2669
# define XXH_RESTRICT /* disable */
2670
#endif
2671
2672
#if (defined(__GNUC__) && (__GNUC__ >= 3)) \
2673
|| (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) \
2674
|| defined(__clang__)
2675
# define XXH_likely(x) __builtin_expect(x, 1)
2676
# define XXH_unlikely(x) __builtin_expect(x, 0)
2677
#else
2678
# define XXH_likely(x) (x)
2679
# define XXH_unlikely(x) (x)
2680
#endif
2681
2682
#if defined(__GNUC__) || defined(__clang__)
2683
# if defined(__ARM_NEON__) || defined(__ARM_NEON) \
2684
|| defined(__aarch64__) || defined(_M_ARM) \
2685
|| defined(_M_ARM64) || defined(_M_ARM64EC)
2686
# define inline __inline__ /* circumvent a clang bug */
2687
# include <arm_neon.h>
2688
# undef inline
2689
# elif defined(__AVX2__)
2690
# include <immintrin.h>
2691
# elif defined(__SSE2__)
2692
# include <emmintrin.h>
2693
# endif
2694
#endif
2695
2696
#if defined(_MSC_VER)
2697
# include <intrin.h>
2698
#endif
2699
2700
/*
2701
* One goal of XXH3 is to make it fast on both 32-bit and 64-bit, while
2702
* remaining a true 64-bit/128-bit hash function.
2703
*
2704
* This is done by prioritizing a subset of 64-bit operations that can be
2705
* emulated without too many steps on the average 32-bit machine.
2706
*
2707
* For example, these two lines seem similar, and run equally fast on 64-bit:
2708
*
2709
* xxh_u64 x;
2710
* x ^= (x >> 47); // good
2711
* x ^= (x >> 13); // bad
2712
*
2713
* However, to a 32-bit machine, there is a major difference.
2714
*
2715
* x ^= (x >> 47) looks like this:
2716
*
2717
* x.lo ^= (x.hi >> (47 - 32));
2718
*
2719
* while x ^= (x >> 13) looks like this:
2720
*
2721
* // note: funnel shifts are not usually cheap.
2722
* x.lo ^= (x.lo >> 13) | (x.hi << (32 - 13));
2723
* x.hi ^= (x.hi >> 13);
2724
*
2725
* The first one is significantly faster than the second, simply because the
2726
* shift is larger than 32. This means:
2727
* - All the bits we need are in the upper 32 bits, so we can ignore the lower
2728
* 32 bits in the shift.
2729
* - The shift result will always fit in the lower 32 bits, and therefore,
2730
* we can ignore the upper 32 bits in the xor.
2731
*
2732
* Thanks to this optimization, XXH3 only requires these features to be efficient:
2733
*
2734
* - Usable unaligned access
2735
* - A 32-bit or 64-bit ALU
2736
* - If 32-bit, a decent ADC instruction
2737
* - A 32 or 64-bit multiply with a 64-bit result
2738
* - For the 128-bit variant, a decent byteswap helps short inputs.
2739
*
2740
* The first two are already required by XXH32, and almost all 32-bit and 64-bit
2741
* platforms which can run XXH32 can run XXH3 efficiently.
2742
*
2743
* Thumb-1, the classic 16-bit only subset of ARM's instruction set, is one
2744
* notable exception.
2745
*
2746
* First of all, Thumb-1 lacks support for the UMULL instruction which
2747
* performs the important long multiply. This means numerous __aeabi_lmul
2748
* calls.
2749
*
2750
* Second of all, the 8 functional registers are just not enough.
2751
* Setup for __aeabi_lmul, byteshift loads, pointers, and all arithmetic need
2752
* Lo registers, and this shuffling results in thousands more MOVs than A32.
2753
*
2754
* A32 and T32 don't have this limitation. They can access all 14 registers,
2755
* do a 32->64 multiply with UMULL, and the flexible operand allowing free
2756
* shifts is helpful, too.
2757
*
2758
* Therefore, we do a quick sanity check.
2759
*
2760
* If compiling Thumb-1 for a target which supports ARM instructions, we will
2761
* emit a warning, as it is not a "sane" platform to compile for.
2762
*
2763
* Usually, if this happens, it is because of an accident and you probably need
2764
* to specify -march, as you likely meant to compile for a newer architecture.
2765
*
2766
* Credit: large sections of the vectorial and asm source code paths
2767
* have been contributed by @easyaspi314
2768
*/
2769
#if defined(__thumb__) && !defined(__thumb2__) && defined(__ARM_ARCH_ISA_ARM)
2770
# warning "XXH3 is highly inefficient without ARM or Thumb-2."
2771
#endif
2772
2773
/* ==========================================
2774
* Vectorization detection
2775
* ========================================== */
2776
2777
#ifdef XXH_DOXYGEN
2778
/*!
2779
* @ingroup tuning
2780
* @brief Overrides the vectorization implementation chosen for XXH3.
2781
*
2782
* Can be defined to 0 to disable SIMD or any of the values mentioned in
2783
* @ref XXH_VECTOR_TYPE.
2784
*
2785
* If this is not defined, it uses predefined macros to determine the best
2786
* implementation.
2787
*/
2788
# define XXH_VECTOR XXH_SCALAR
2789
/*!
2790
* @ingroup tuning
2791
* @brief Possible values for @ref XXH_VECTOR.
2792
*
2793
* Note that these are actually implemented as macros.
2794
*
2795
* If this is not defined, it is detected automatically.
2796
* @ref XXH_X86DISPATCH overrides this.
2797
*/
2798
enum XXH_VECTOR_TYPE /* fake enum */ {
2799
XXH_SCALAR = 0, /*!< Portable scalar version */
2800
XXH_SSE2 = 1, /*!<
2801
* SSE2 for Pentium 4, Opteron, all x86_64.
2802
*
2803
* @note SSE2 is also guaranteed on Windows 10, macOS, and
2804
* Android x86.
2805
*/
2806
XXH_AVX2 = 2, /*!< AVX2 for Haswell and Bulldozer */
2807
XXH_AVX512 = 3, /*!< AVX512 for Skylake and Icelake */
2808
XXH_NEON = 4, /*!< NEON for most ARMv7-A and all AArch64 */
2809
XXH_VSX = 5, /*!< VSX and ZVector for POWER8/z13 (64-bit) */
2810
};
2811
/*!
2812
* @ingroup tuning
2813
* @brief Selects the minimum alignment for XXH3's accumulators.
2814
*
2815
* When using SIMD, this should match the alignment reqired for said vector
2816
* type, so, for example, 32 for AVX2.
2817
*
2818
* Default: Auto detected.
2819
*/
2820
# define XXH_ACC_ALIGN 8
2821
#endif
2822
2823
/* Actual definition */
2824
#ifndef XXH_DOXYGEN
2825
# define XXH_SCALAR 0
2826
# define XXH_SSE2 1
2827
# define XXH_AVX2 2
2828
# define XXH_AVX512 3
2829
# define XXH_NEON 4
2830
# define XXH_VSX 5
2831
#endif
2832
2833
#ifndef XXH_VECTOR /* can be defined on command line */
2834
# if ( \
2835
defined(__ARM_NEON__) || defined(__ARM_NEON) /* gcc */ \
2836
|| defined(_M_ARM) || defined(_M_ARM64) || defined(_M_ARM64EC) /* msvc */ \
2837
) && ( \
2838
defined(_WIN32) || defined(__LITTLE_ENDIAN__) /* little endian only */ \
2839
|| (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) \
2840
)
2841
# define XXH_VECTOR XXH_NEON
2842
# elif defined(__AVX512F__)
2843
# define XXH_VECTOR XXH_AVX512
2844
# elif defined(__AVX2__)
2845
# define XXH_VECTOR XXH_AVX2
2846
# elif defined(__SSE2__) || defined(_M_AMD64) || defined(_M_X64) || (defined(_M_IX86_FP) && (_M_IX86_FP == 2))
2847
# define XXH_VECTOR XXH_SSE2
2848
# elif (defined(__PPC64__) && defined(__POWER8_VECTOR__)) \
2849
|| (defined(__s390x__) && defined(__VEC__)) \
2850
&& defined(__GNUC__) /* TODO: IBM XL */
2851
# define XXH_VECTOR XXH_VSX
2852
# else
2853
# define XXH_VECTOR XXH_SCALAR
2854
# endif
2855
#endif
2856
2857
/*
2858
* Controls the alignment of the accumulator,
2859
* for compatibility with aligned vector loads, which are usually faster.
2860
*/
2861
#ifndef XXH_ACC_ALIGN
2862
# if defined(XXH_X86DISPATCH)
2863
# define XXH_ACC_ALIGN 64 /* for compatibility with avx512 */
2864
# elif XXH_VECTOR == XXH_SCALAR /* scalar */
2865
# define XXH_ACC_ALIGN 8
2866
# elif XXH_VECTOR == XXH_SSE2 /* sse2 */
2867
# define XXH_ACC_ALIGN 16
2868
# elif XXH_VECTOR == XXH_AVX2 /* avx2 */
2869
# define XXH_ACC_ALIGN 32
2870
# elif XXH_VECTOR == XXH_NEON /* neon */
2871
# define XXH_ACC_ALIGN 16
2872
# elif XXH_VECTOR == XXH_VSX /* vsx */
2873
# define XXH_ACC_ALIGN 16
2874
# elif XXH_VECTOR == XXH_AVX512 /* avx512 */
2875
# define XXH_ACC_ALIGN 64
2876
# endif
2877
#endif
2878
2879
#if defined(XXH_X86DISPATCH) || XXH_VECTOR == XXH_SSE2 \
2880
|| XXH_VECTOR == XXH_AVX2 || XXH_VECTOR == XXH_AVX512
2881
# define XXH_SEC_ALIGN XXH_ACC_ALIGN
2882
#else
2883
# define XXH_SEC_ALIGN 8
2884
#endif
2885
2886
/*
2887
* UGLY HACK:
2888
* GCC usually generates the best code with -O3 for xxHash.
2889
*
2890
* However, when targeting AVX2, it is overzealous in its unrolling resulting
2891
* in code roughly 3/4 the speed of Clang.
2892
*
2893
* There are other issues, such as GCC splitting _mm256_loadu_si256 into
2894
* _mm_loadu_si128 + _mm256_inserti128_si256. This is an optimization which
2895
* only applies to Sandy and Ivy Bridge... which don't even support AVX2.
2896
*
2897
* That is why when compiling the AVX2 version, it is recommended to use either
2898
* -O2 -mavx2 -march=haswell
2899
* or
2900
* -O2 -mavx2 -mno-avx256-split-unaligned-load
2901
* for decent performance, or to use Clang instead.
2902
*
2903
* Fortunately, we can control the first one with a pragma that forces GCC into
2904
* -O2, but the other one we can't control without "failed to inline always
2905
* inline function due to target mismatch" warnings.
2906
*/
2907
#if XXH_VECTOR == XXH_AVX2 /* AVX2 */ \
2908
&& defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
2909
&& defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) /* respect -O0 and -Os */
2910
# pragma GCC push_options
2911
# pragma GCC optimize("-O2")
2912
#endif
2913
2914
2915
#if XXH_VECTOR == XXH_NEON
2916
/*
2917
* NEON's setup for vmlal_u32 is a little more complicated than it is on
2918
* SSE2, AVX2, and VSX.
2919
*
2920
* While PMULUDQ and VMULEUW both perform a mask, VMLAL.U32 performs an upcast.
2921
*
2922
* To do the same operation, the 128-bit 'Q' register needs to be split into
2923
* two 64-bit 'D' registers, performing this operation::
2924
*
2925
* [ a | b ]
2926
* | '---------. .--------' |
2927
* | x |
2928
* | .---------' '--------. |
2929
* [ a & 0xFFFFFFFF | b & 0xFFFFFFFF ],[ a >> 32 | b >> 32 ]
2930
*
2931
* Due to significant changes in aarch64, the fastest method for aarch64 is
2932
* completely different than the fastest method for ARMv7-A.
2933
*
2934
* ARMv7-A treats D registers as unions overlaying Q registers, so modifying
2935
* D11 will modify the high half of Q5. This is similar to how modifying AH
2936
* will only affect bits 8-15 of AX on x86.
2937
*
2938
* VZIP takes two registers, and puts even lanes in one register and odd lanes
2939
* in the other.
2940
*
2941
* On ARMv7-A, this strangely modifies both parameters in place instead of
2942
* taking the usual 3-operand form.
2943
*
2944
* Therefore, if we want to do this, we can simply use a D-form VZIP.32 on the
2945
* lower and upper halves of the Q register to end up with the high and low
2946
* halves where we want - all in one instruction.
2947
*
2948
* vzip.32 d10, d11 @ d10 = { d10[0], d11[0] }; d11 = { d10[1], d11[1] }
2949
*
2950
* Unfortunately we need inline assembly for this: Instructions modifying two
2951
* registers at once is not possible in GCC or Clang's IR, and they have to
2952
* create a copy.
2953
*
2954
* aarch64 requires a different approach.
2955
*
2956
* In order to make it easier to write a decent compiler for aarch64, many
2957
* quirks were removed, such as conditional execution.
2958
*
2959
* NEON was also affected by this.
2960
*
2961
* aarch64 cannot access the high bits of a Q-form register, and writes to a
2962
* D-form register zero the high bits, similar to how writes to W-form scalar
2963
* registers (or DWORD registers on x86_64) work.
2964
*
2965
* The formerly free vget_high intrinsics now require a vext (with a few
2966
* exceptions)
2967
*
2968
* Additionally, VZIP was replaced by ZIP1 and ZIP2, which are the equivalent
2969
* of PUNPCKL* and PUNPCKH* in SSE, respectively, in order to only modify one
2970
* operand.
2971
*
2972
* The equivalent of the VZIP.32 on the lower and upper halves would be this
2973
* mess:
2974
*
2975
* ext v2.4s, v0.4s, v0.4s, #2 // v2 = { v0[2], v0[3], v0[0], v0[1] }
2976
* zip1 v1.2s, v0.2s, v2.2s // v1 = { v0[0], v2[0] }
2977
* zip2 v0.2s, v0.2s, v1.2s // v0 = { v0[1], v2[1] }
2978
*
2979
* Instead, we use a literal downcast, vmovn_u64 (XTN), and vshrn_n_u64 (SHRN):
2980
*
2981
* shrn v1.2s, v0.2d, #32 // v1 = (uint32x2_t)(v0 >> 32);
2982
* xtn v0.2s, v0.2d // v0 = (uint32x2_t)(v0 & 0xFFFFFFFF);
2983
*
2984
* This is available on ARMv7-A, but is less efficient than a single VZIP.32.
2985
*/
2986
2987
/*!
2988
* Function-like macro:
2989
* void XXH_SPLIT_IN_PLACE(uint64x2_t &in, uint32x2_t &outLo, uint32x2_t &outHi)
2990
* {
2991
* outLo = (uint32x2_t)(in & 0xFFFFFFFF);
2992
* outHi = (uint32x2_t)(in >> 32);
2993
* in = UNDEFINED;
2994
* }
2995
*/
2996
# if !defined(XXH_NO_VZIP_HACK) /* define to disable */ \
2997
&& (defined(__GNUC__) || defined(__clang__)) \
2998
&& (defined(__arm__) || defined(__thumb__) || defined(_M_ARM))
2999
# define XXH_SPLIT_IN_PLACE(in, outLo, outHi) \
3000
do { \
3001
/* Undocumented GCC/Clang operand modifier: %e0 = lower D half, %f0 = upper D half */ \
3002
/* https://github.com/gcc-mirror/gcc/blob/38cf91e5/gcc/config/arm/arm.c#L22486 */ \
3003
/* https://github.com/llvm-mirror/llvm/blob/2c4ca683/lib/Target/ARM/ARMAsmPrinter.cpp#L399 */ \
3004
__asm__("vzip.32 %e0, %f0" : "+w" (in)); \
3005
(outLo) = vget_low_u32 (vreinterpretq_u32_u64(in)); \
3006
(outHi) = vget_high_u32(vreinterpretq_u32_u64(in)); \
3007
} while (0)
3008
# else
3009
# define XXH_SPLIT_IN_PLACE(in, outLo, outHi) \
3010
do { \
3011
(outLo) = vmovn_u64 (in); \
3012
(outHi) = vshrn_n_u64 ((in), 32); \
3013
} while (0)
3014
# endif
3015
3016
/*!
3017
* @ingroup tuning
3018
* @brief Controls the NEON to scalar ratio for XXH3
3019
*
3020
* On AArch64 when not optimizing for size, XXH3 will run 6 lanes using NEON and
3021
* 2 lanes on scalar by default.
3022
*
3023
* This can be set to 2, 4, 6, or 8. ARMv7 will default to all 8 NEON lanes, as the
3024
* emulated 64-bit arithmetic is too slow.
3025
*
3026
* Modern ARM CPUs are _very_ sensitive to how their pipelines are used.
3027
*
3028
* For example, the Cortex-A73 can dispatch 3 micro-ops per cycle, but it can't
3029
* have more than 2 NEON (F0/F1) micro-ops. If you are only using NEON instructions,
3030
* you are only using 2/3 of the CPU bandwidth.
3031
*
3032
* This is even more noticable on the more advanced cores like the A76 which
3033
* can dispatch 8 micro-ops per cycle, but still only 2 NEON micro-ops at once.
3034
*
3035
* Therefore, @ref XXH3_NEON_LANES lanes will be processed using NEON, and the
3036
* remaining lanes will use scalar instructions. This improves the bandwidth
3037
* and also gives the integer pipelines something to do besides twiddling loop
3038
* counters and pointers.
3039
*
3040
* This change benefits CPUs with large micro-op buffers without negatively affecting
3041
* other CPUs:
3042
*
3043
* | Chipset | Dispatch type | NEON only | 6:2 hybrid | Diff. |
3044
* |:----------------------|:--------------------|----------:|-----------:|------:|
3045
* | Snapdragon 730 (A76) | 2 NEON/8 micro-ops | 8.8 GB/s | 10.1 GB/s | ~16% |
3046
* | Snapdragon 835 (A73) | 2 NEON/3 micro-ops | 5.1 GB/s | 5.3 GB/s | ~5% |
3047
* | Marvell PXA1928 (A53) | In-order dual-issue | 1.9 GB/s | 1.9 GB/s | 0% |
3048
*
3049
* It also seems to fix some bad codegen on GCC, making it almost as fast as clang.
3050
*
3051
* @see XXH3_accumulate_512_neon()
3052
*/
3053
# ifndef XXH3_NEON_LANES
3054
# if (defined(__aarch64__) || defined(__arm64__) || defined(_M_ARM64) || defined(_M_ARM64EC)) \
3055
&& !defined(__OPTIMIZE_SIZE__)
3056
# define XXH3_NEON_LANES 6
3057
# else
3058
# define XXH3_NEON_LANES XXH_ACC_NB
3059
# endif
3060
# endif
3061
#endif /* XXH_VECTOR == XXH_NEON */
3062
3063
/*
3064
* VSX and Z Vector helpers.
3065
*
3066
* This is very messy, and any pull requests to clean this up are welcome.
3067
*
3068
* There are a lot of problems with supporting VSX and s390x, due to
3069
* inconsistent intrinsics, spotty coverage, and multiple endiannesses.
3070
*/
3071
#if XXH_VECTOR == XXH_VSX
3072
# if defined(__s390x__)
3073
# include <s390intrin.h>
3074
# else
3075
/* gcc's altivec.h can have the unwanted consequence to unconditionally
3076
* #define bool, vector, and pixel keywords,
3077
* with bad consequences for programs already using these keywords for other purposes.
3078
* The paragraph defining these macros is skipped when __APPLE_ALTIVEC__ is defined.
3079
* __APPLE_ALTIVEC__ is _generally_ defined automatically by the compiler,
3080
* but it seems that, in some cases, it isn't.
3081
* Force the build macro to be defined, so that keywords are not altered.
3082
*/
3083
# if defined(__GNUC__) && !defined(__APPLE_ALTIVEC__)
3084
# define __APPLE_ALTIVEC__
3085
# endif
3086
# include <altivec.h>
3087
# endif
3088
3089
typedef __vector unsigned long long xxh_u64x2;
3090
typedef __vector unsigned char xxh_u8x16;
3091
typedef __vector unsigned xxh_u32x4;
3092
3093
# ifndef XXH_VSX_BE
3094
# if defined(__BIG_ENDIAN__) \
3095
|| (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
3096
# define XXH_VSX_BE 1
3097
# elif defined(__VEC_ELEMENT_REG_ORDER__) && __VEC_ELEMENT_REG_ORDER__ == __ORDER_BIG_ENDIAN__
3098
# warning "-maltivec=be is not recommended. Please use native endianness."
3099
# define XXH_VSX_BE 1
3100
# else
3101
# define XXH_VSX_BE 0
3102
# endif
3103
# endif /* !defined(XXH_VSX_BE) */
3104
3105
# if XXH_VSX_BE
3106
# if defined(__POWER9_VECTOR__) || (defined(__clang__) && defined(__s390x__))
3107
# define XXH_vec_revb vec_revb
3108
# else
3109
/*!
3110
* A polyfill for POWER9's vec_revb().
3111
*/
3112
XXH_FORCE_INLINE xxh_u64x2 XXH_vec_revb(xxh_u64x2 val)
3113
{
3114
xxh_u8x16 const vByteSwap = { 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
3115
0x0F, 0x0E, 0x0D, 0x0C, 0x0B, 0x0A, 0x09, 0x08 };
3116
return vec_perm(val, val, vByteSwap);
3117
}
3118
# endif
3119
# endif /* XXH_VSX_BE */
3120
3121
/*!
3122
* Performs an unaligned vector load and byte swaps it on big endian.
3123
*/
3124
XXH_FORCE_INLINE xxh_u64x2 XXH_vec_loadu(const void *ptr)
3125
{
3126
xxh_u64x2 ret;
3127
XXH_memcpy(&ret, ptr, sizeof(xxh_u64x2));
3128
# if XXH_VSX_BE
3129
ret = XXH_vec_revb(ret);
3130
# endif
3131
return ret;
3132
}
3133
3134
/*
3135
* vec_mulo and vec_mule are very problematic intrinsics on PowerPC
3136
*
3137
* These intrinsics weren't added until GCC 8, despite existing for a while,
3138
* and they are endian dependent. Also, their meaning swap depending on version.
3139
* */
3140
# if defined(__s390x__)
3141
/* s390x is always big endian, no issue on this platform */
3142
# define XXH_vec_mulo vec_mulo
3143
# define XXH_vec_mule vec_mule
3144
# elif defined(__clang__) && XXH_HAS_BUILTIN(__builtin_altivec_vmuleuw)
3145
/* Clang has a better way to control this, we can just use the builtin which doesn't swap. */
3146
# define XXH_vec_mulo __builtin_altivec_vmulouw
3147
# define XXH_vec_mule __builtin_altivec_vmuleuw
3148
# else
3149
/* gcc needs inline assembly */
3150
/* Adapted from https://github.com/google/highwayhash/blob/master/highwayhash/hh_vsx.h. */
3151
XXH_FORCE_INLINE xxh_u64x2 XXH_vec_mulo(xxh_u32x4 a, xxh_u32x4 b)
3152
{
3153
xxh_u64x2 result;
3154
__asm__("vmulouw %0, %1, %2" : "=v" (result) : "v" (a), "v" (b));
3155
return result;
3156
}
3157
XXH_FORCE_INLINE xxh_u64x2 XXH_vec_mule(xxh_u32x4 a, xxh_u32x4 b)
3158
{
3159
xxh_u64x2 result;
3160
__asm__("vmuleuw %0, %1, %2" : "=v" (result) : "v" (a), "v" (b));
3161
return result;
3162
}
3163
# endif /* XXH_vec_mulo, XXH_vec_mule */
3164
#endif /* XXH_VECTOR == XXH_VSX */
3165
3166
3167
/* prefetch
3168
* can be disabled, by declaring XXH_NO_PREFETCH build macro */
3169
#if defined(XXH_NO_PREFETCH)
3170
# define XXH_PREFETCH(ptr) (void)(ptr) /* disabled */
3171
#else
3172
# if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86)) /* _mm_prefetch() not defined outside of x86/x64 */
3173
# include <mmintrin.h> /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
3174
# define XXH_PREFETCH(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
3175
# elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
3176
# define XXH_PREFETCH(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */)
3177
# else
3178
# define XXH_PREFETCH(ptr) (void)(ptr) /* disabled */
3179
# endif
3180
#endif /* XXH_NO_PREFETCH */
3181
3182
3183
/* ==========================================
3184
* XXH3 default settings
3185
* ========================================== */
3186
3187
#define XXH_SECRET_DEFAULT_SIZE 192 /* minimum XXH3_SECRET_SIZE_MIN */
3188
3189
#if (XXH_SECRET_DEFAULT_SIZE < XXH3_SECRET_SIZE_MIN)
3190
# error "default keyset is not large enough"
3191
#endif
3192
3193
/*! Pseudorandom secret taken directly from FARSH. */
3194
XXH_ALIGN(64) static const xxh_u8 XXH3_kSecret[XXH_SECRET_DEFAULT_SIZE] = {
3195
0xb8, 0xfe, 0x6c, 0x39, 0x23, 0xa4, 0x4b, 0xbe, 0x7c, 0x01, 0x81, 0x2c, 0xf7, 0x21, 0xad, 0x1c,
3196
0xde, 0xd4, 0x6d, 0xe9, 0x83, 0x90, 0x97, 0xdb, 0x72, 0x40, 0xa4, 0xa4, 0xb7, 0xb3, 0x67, 0x1f,
3197
0xcb, 0x79, 0xe6, 0x4e, 0xcc, 0xc0, 0xe5, 0x78, 0x82, 0x5a, 0xd0, 0x7d, 0xcc, 0xff, 0x72, 0x21,
3198
0xb8, 0x08, 0x46, 0x74, 0xf7, 0x43, 0x24, 0x8e, 0xe0, 0x35, 0x90, 0xe6, 0x81, 0x3a, 0x26, 0x4c,
3199
0x3c, 0x28, 0x52, 0xbb, 0x91, 0xc3, 0x00, 0xcb, 0x88, 0xd0, 0x65, 0x8b, 0x1b, 0x53, 0x2e, 0xa3,
3200
0x71, 0x64, 0x48, 0x97, 0xa2, 0x0d, 0xf9, 0x4e, 0x38, 0x19, 0xef, 0x46, 0xa9, 0xde, 0xac, 0xd8,
3201
0xa8, 0xfa, 0x76, 0x3f, 0xe3, 0x9c, 0x34, 0x3f, 0xf9, 0xdc, 0xbb, 0xc7, 0xc7, 0x0b, 0x4f, 0x1d,
3202
0x8a, 0x51, 0xe0, 0x4b, 0xcd, 0xb4, 0x59, 0x31, 0xc8, 0x9f, 0x7e, 0xc9, 0xd9, 0x78, 0x73, 0x64,
3203
0xea, 0xc5, 0xac, 0x83, 0x34, 0xd3, 0xeb, 0xc3, 0xc5, 0x81, 0xa0, 0xff, 0xfa, 0x13, 0x63, 0xeb,
3204
0x17, 0x0d, 0xdd, 0x51, 0xb7, 0xf0, 0xda, 0x49, 0xd3, 0x16, 0x55, 0x26, 0x29, 0xd4, 0x68, 0x9e,
3205
0x2b, 0x16, 0xbe, 0x58, 0x7d, 0x47, 0xa1, 0xfc, 0x8f, 0xf8, 0xb8, 0xd1, 0x7a, 0xd0, 0x31, 0xce,
3206
0x45, 0xcb, 0x3a, 0x8f, 0x95, 0x16, 0x04, 0x28, 0xaf, 0xd7, 0xfb, 0xca, 0xbb, 0x4b, 0x40, 0x7e,
3207
};
3208
3209
3210
#ifdef XXH_OLD_NAMES
3211
# define kSecret XXH3_kSecret
3212
#endif
3213
3214
#ifdef XXH_DOXYGEN
3215
/*!
3216
* @brief Calculates a 32-bit to 64-bit long multiply.
3217
*
3218
* Implemented as a macro.
3219
*
3220
* Wraps `__emulu` on MSVC x86 because it tends to call `__allmul` when it doesn't
3221
* need to (but it shouldn't need to anyways, it is about 7 instructions to do
3222
* a 64x64 multiply...). Since we know that this will _always_ emit `MULL`, we
3223
* use that instead of the normal method.
3224
*
3225
* If you are compiling for platforms like Thumb-1 and don't have a better option,
3226
* you may also want to write your own long multiply routine here.
3227
*
3228
* @param x, y Numbers to be multiplied
3229
* @return 64-bit product of the low 32 bits of @p x and @p y.
3230
*/
3231
XXH_FORCE_INLINE xxh_u64
3232
XXH_mult32to64(xxh_u64 x, xxh_u64 y)
3233
{
3234
return (x & 0xFFFFFFFF) * (y & 0xFFFFFFFF);
3235
}
3236
#elif defined(_MSC_VER) && defined(_M_IX86)
3237
# define XXH_mult32to64(x, y) __emulu((unsigned)(x), (unsigned)(y))
3238
#else
3239
/*
3240
* Downcast + upcast is usually better than masking on older compilers like
3241
* GCC 4.2 (especially 32-bit ones), all without affecting newer compilers.
3242
*
3243
* The other method, (x & 0xFFFFFFFF) * (y & 0xFFFFFFFF), will AND both operands
3244
* and perform a full 64x64 multiply -- entirely redundant on 32-bit.
3245
*/
3246
# define XXH_mult32to64(x, y) ((xxh_u64)(xxh_u32)(x) * (xxh_u64)(xxh_u32)(y))
3247
#endif
3248
3249
/*!
3250
* @brief Calculates a 64->128-bit long multiply.
3251
*
3252
* Uses `__uint128_t` and `_umul128` if available, otherwise uses a scalar
3253
* version.
3254
*
3255
* @param lhs , rhs The 64-bit integers to be multiplied
3256
* @return The 128-bit result represented in an @ref XXH128_hash_t.
3257
*/
3258
static XXH128_hash_t
3259
XXH_mult64to128(xxh_u64 lhs, xxh_u64 rhs)
3260
{
3261
/*
3262
* GCC/Clang __uint128_t method.
3263
*
3264
* On most 64-bit targets, GCC and Clang define a __uint128_t type.
3265
* This is usually the best way as it usually uses a native long 64-bit
3266
* multiply, such as MULQ on x86_64 or MUL + UMULH on aarch64.
3267
*
3268
* Usually.
3269
*
3270
* Despite being a 32-bit platform, Clang (and emscripten) define this type
3271
* despite not having the arithmetic for it. This results in a laggy
3272
* compiler builtin call which calculates a full 128-bit multiply.
3273
* In that case it is best to use the portable one.
3274
* https://github.com/Cyan4973/xxHash/issues/211#issuecomment-515575677
3275
*/
3276
#if (defined(__GNUC__) || defined(__clang__)) && !defined(__wasm__) \
3277
&& defined(__SIZEOF_INT128__) \
3278
|| (defined(_INTEGRAL_MAX_BITS) && _INTEGRAL_MAX_BITS >= 128)
3279
3280
__uint128_t const product = (__uint128_t)lhs * (__uint128_t)rhs;
3281
XXH128_hash_t r128;
3282
r128.low64 = (xxh_u64)(product);
3283
r128.high64 = (xxh_u64)(product >> 64);
3284
return r128;
3285
3286
/*
3287
* MSVC for x64's _umul128 method.
3288
*
3289
* xxh_u64 _umul128(xxh_u64 Multiplier, xxh_u64 Multiplicand, xxh_u64 *HighProduct);
3290
*
3291
* This compiles to single operand MUL on x64.
3292
*/
3293
#elif (defined(_M_X64) || defined(_M_IA64)) && !defined(_M_ARM64EC)
3294
3295
#ifndef _MSC_VER
3296
# pragma intrinsic(_umul128)
3297
#endif
3298
xxh_u64 product_high;
3299
xxh_u64 const product_low = _umul128(lhs, rhs, &product_high);
3300
XXH128_hash_t r128;
3301
r128.low64 = product_low;
3302
r128.high64 = product_high;
3303
return r128;
3304
3305
/*
3306
* MSVC for ARM64's __umulh method.
3307
*
3308
* This compiles to the same MUL + UMULH as GCC/Clang's __uint128_t method.
3309
*/
3310
#elif defined(_M_ARM64) || defined(_M_ARM64EC)
3311
3312
#ifndef _MSC_VER
3313
# pragma intrinsic(__umulh)
3314
#endif
3315
XXH128_hash_t r128;
3316
r128.low64 = lhs * rhs;
3317
r128.high64 = __umulh(lhs, rhs);
3318
return r128;
3319
3320
#else
3321
/*
3322
* Portable scalar method. Optimized for 32-bit and 64-bit ALUs.
3323
*
3324
* This is a fast and simple grade school multiply, which is shown below
3325
* with base 10 arithmetic instead of base 0x100000000.
3326
*
3327
* 9 3 // D2 lhs = 93
3328
* x 7 5 // D2 rhs = 75
3329
* ----------
3330
* 1 5 // D2 lo_lo = (93 % 10) * (75 % 10) = 15
3331
* 4 5 | // D2 hi_lo = (93 / 10) * (75 % 10) = 45
3332
* 2 1 | // D2 lo_hi = (93 % 10) * (75 / 10) = 21
3333
* + 6 3 | | // D2 hi_hi = (93 / 10) * (75 / 10) = 63
3334
* ---------
3335
* 2 7 | // D2 cross = (15 / 10) + (45 % 10) + 21 = 27
3336
* + 6 7 | | // D2 upper = (27 / 10) + (45 / 10) + 63 = 67
3337
* ---------
3338
* 6 9 7 5 // D4 res = (27 * 10) + (15 % 10) + (67 * 100) = 6975
3339
*
3340
* The reasons for adding the products like this are:
3341
* 1. It avoids manual carry tracking. Just like how
3342
* (9 * 9) + 9 + 9 = 99, the same applies with this for UINT64_MAX.
3343
* This avoids a lot of complexity.
3344
*
3345
* 2. It hints for, and on Clang, compiles to, the powerful UMAAL
3346
* instruction available in ARM's Digital Signal Processing extension
3347
* in 32-bit ARMv6 and later, which is shown below:
3348
*
3349
* void UMAAL(xxh_u32 *RdLo, xxh_u32 *RdHi, xxh_u32 Rn, xxh_u32 Rm)
3350
* {
3351
* xxh_u64 product = (xxh_u64)*RdLo * (xxh_u64)*RdHi + Rn + Rm;
3352
* *RdLo = (xxh_u32)(product & 0xFFFFFFFF);
3353
* *RdHi = (xxh_u32)(product >> 32);
3354
* }
3355
*
3356
* This instruction was designed for efficient long multiplication, and
3357
* allows this to be calculated in only 4 instructions at speeds
3358
* comparable to some 64-bit ALUs.
3359
*
3360
* 3. It isn't terrible on other platforms. Usually this will be a couple
3361
* of 32-bit ADD/ADCs.
3362
*/
3363
3364
/* First calculate all of the cross products. */
3365
xxh_u64 const lo_lo = XXH_mult32to64(lhs & 0xFFFFFFFF, rhs & 0xFFFFFFFF);
3366
xxh_u64 const hi_lo = XXH_mult32to64(lhs >> 32, rhs & 0xFFFFFFFF);
3367
xxh_u64 const lo_hi = XXH_mult32to64(lhs & 0xFFFFFFFF, rhs >> 32);
3368
xxh_u64 const hi_hi = XXH_mult32to64(lhs >> 32, rhs >> 32);
3369
3370
/* Now add the products together. These will never overflow. */
3371
xxh_u64 const cross = (lo_lo >> 32) + (hi_lo & 0xFFFFFFFF) + lo_hi;
3372
xxh_u64 const upper = (hi_lo >> 32) + (cross >> 32) + hi_hi;
3373
xxh_u64 const lower = (cross << 32) | (lo_lo & 0xFFFFFFFF);
3374
3375
XXH128_hash_t r128;
3376
r128.low64 = lower;
3377
r128.high64 = upper;
3378
return r128;
3379
#endif
3380
}
3381
3382
/*!
3383
* @brief Calculates a 64-bit to 128-bit multiply, then XOR folds it.
3384
*
3385
* The reason for the separate function is to prevent passing too many structs
3386
* around by value. This will hopefully inline the multiply, but we don't force it.
3387
*
3388
* @param lhs , rhs The 64-bit integers to multiply
3389
* @return The low 64 bits of the product XOR'd by the high 64 bits.
3390
* @see XXH_mult64to128()
3391
*/
3392
static xxh_u64
3393
XXH3_mul128_fold64(xxh_u64 lhs, xxh_u64 rhs)
3394
{
3395
XXH128_hash_t product = XXH_mult64to128(lhs, rhs);
3396
return product.low64 ^ product.high64;
3397
}
3398
3399
/*! Seems to produce slightly better code on GCC for some reason. */
3400
XXH_FORCE_INLINE xxh_u64 XXH_xorshift64(xxh_u64 v64, int shift)
3401
{
3402
XXH_ASSERT(0 <= shift && shift < 64);
3403
return v64 ^ (v64 >> shift);
3404
}
3405
3406
/*
3407
* This is a fast avalanche stage,
3408
* suitable when input bits are already partially mixed
3409
*/
3410
static XXH64_hash_t XXH3_avalanche(xxh_u64 h64)
3411
{
3412
h64 = XXH_xorshift64(h64, 37);
3413
h64 *= 0x165667919E3779F9ULL;
3414
h64 = XXH_xorshift64(h64, 32);
3415
return h64;
3416
}
3417
3418
/*
3419
* This is a stronger avalanche,
3420
* inspired by Pelle Evensen's rrmxmx
3421
* preferable when input has not been previously mixed
3422
*/
3423
static XXH64_hash_t XXH3_rrmxmx(xxh_u64 h64, xxh_u64 len)
3424
{
3425
/* this mix is inspired by Pelle Evensen's rrmxmx */
3426
h64 ^= XXH_rotl64(h64, 49) ^ XXH_rotl64(h64, 24);
3427
h64 *= 0x9FB21C651E98DF25ULL;
3428
h64 ^= (h64 >> 35) + len ;
3429
h64 *= 0x9FB21C651E98DF25ULL;
3430
return XXH_xorshift64(h64, 28);
3431
}
3432
3433
3434
/* ==========================================
3435
* Short keys
3436
* ==========================================
3437
* One of the shortcomings of XXH32 and XXH64 was that their performance was
3438
* sub-optimal on short lengths. It used an iterative algorithm which strongly
3439
* favored lengths that were a multiple of 4 or 8.
3440
*
3441
* Instead of iterating over individual inputs, we use a set of single shot
3442
* functions which piece together a range of lengths and operate in constant time.
3443
*
3444
* Additionally, the number of multiplies has been significantly reduced. This
3445
* reduces latency, especially when emulating 64-bit multiplies on 32-bit.
3446
*
3447
* Depending on the platform, this may or may not be faster than XXH32, but it
3448
* is almost guaranteed to be faster than XXH64.
3449
*/
3450
3451
/*
3452
* At very short lengths, there isn't enough input to fully hide secrets, or use
3453
* the entire secret.
3454
*
3455
* There is also only a limited amount of mixing we can do before significantly
3456
* impacting performance.
3457
*
3458
* Therefore, we use different sections of the secret and always mix two secret
3459
* samples with an XOR. This should have no effect on performance on the
3460
* seedless or withSeed variants because everything _should_ be constant folded
3461
* by modern compilers.
3462
*
3463
* The XOR mixing hides individual parts of the secret and increases entropy.
3464
*
3465
* This adds an extra layer of strength for custom secrets.
3466
*/
3467
XXH_FORCE_INLINE XXH64_hash_t
3468
XXH3_len_1to3_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3469
{
3470
XXH_ASSERT(input != NULL);
3471
XXH_ASSERT(1 <= len && len <= 3);
3472
XXH_ASSERT(secret != NULL);
3473
/*
3474
* len = 1: combined = { input[0], 0x01, input[0], input[0] }
3475
* len = 2: combined = { input[1], 0x02, input[0], input[1] }
3476
* len = 3: combined = { input[2], 0x03, input[0], input[1] }
3477
*/
3478
{ xxh_u8 const c1 = input[0];
3479
xxh_u8 const c2 = input[len >> 1];
3480
xxh_u8 const c3 = input[len - 1];
3481
xxh_u32 const combined = ((xxh_u32)c1 << 16) | ((xxh_u32)c2 << 24)
3482
| ((xxh_u32)c3 << 0) | ((xxh_u32)len << 8);
3483
xxh_u64 const bitflip = (XXH_readLE32(secret) ^ XXH_readLE32(secret+4)) + seed;
3484
xxh_u64 const keyed = (xxh_u64)combined ^ bitflip;
3485
return XXH64_avalanche(keyed);
3486
}
3487
}
3488
3489
XXH_FORCE_INLINE XXH64_hash_t
3490
XXH3_len_4to8_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3491
{
3492
XXH_ASSERT(input != NULL);
3493
XXH_ASSERT(secret != NULL);
3494
XXH_ASSERT(4 <= len && len <= 8);
3495
seed ^= (xxh_u64)XXH_swap32((xxh_u32)seed) << 32;
3496
{ xxh_u32 const input1 = XXH_readLE32(input);
3497
xxh_u32 const input2 = XXH_readLE32(input + len - 4);
3498
xxh_u64 const bitflip = (XXH_readLE64(secret+8) ^ XXH_readLE64(secret+16)) - seed;
3499
xxh_u64 const input64 = input2 + (((xxh_u64)input1) << 32);
3500
xxh_u64 const keyed = input64 ^ bitflip;
3501
return XXH3_rrmxmx(keyed, len);
3502
}
3503
}
3504
3505
XXH_FORCE_INLINE XXH64_hash_t
3506
XXH3_len_9to16_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3507
{
3508
XXH_ASSERT(input != NULL);
3509
XXH_ASSERT(secret != NULL);
3510
XXH_ASSERT(9 <= len && len <= 16);
3511
{ xxh_u64 const bitflip1 = (XXH_readLE64(secret+24) ^ XXH_readLE64(secret+32)) + seed;
3512
xxh_u64 const bitflip2 = (XXH_readLE64(secret+40) ^ XXH_readLE64(secret+48)) - seed;
3513
xxh_u64 const input_lo = XXH_readLE64(input) ^ bitflip1;
3514
xxh_u64 const input_hi = XXH_readLE64(input + len - 8) ^ bitflip2;
3515
xxh_u64 const acc = len
3516
+ XXH_swap64(input_lo) + input_hi
3517
+ XXH3_mul128_fold64(input_lo, input_hi);
3518
return XXH3_avalanche(acc);
3519
}
3520
}
3521
3522
XXH_FORCE_INLINE XXH64_hash_t
3523
XXH3_len_0to16_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3524
{
3525
XXH_ASSERT(len <= 16);
3526
{ if (XXH_likely(len > 8)) return XXH3_len_9to16_64b(input, len, secret, seed);
3527
if (XXH_likely(len >= 4)) return XXH3_len_4to8_64b(input, len, secret, seed);
3528
if (len) return XXH3_len_1to3_64b(input, len, secret, seed);
3529
return XXH64_avalanche(seed ^ (XXH_readLE64(secret+56) ^ XXH_readLE64(secret+64)));
3530
}
3531
}
3532
3533
/*
3534
* DISCLAIMER: There are known *seed-dependent* multicollisions here due to
3535
* multiplication by zero, affecting hashes of lengths 17 to 240.
3536
*
3537
* However, they are very unlikely.
3538
*
3539
* Keep this in mind when using the unseeded XXH3_64bits() variant: As with all
3540
* unseeded non-cryptographic hashes, it does not attempt to defend itself
3541
* against specially crafted inputs, only random inputs.
3542
*
3543
* Compared to classic UMAC where a 1 in 2^31 chance of 4 consecutive bytes
3544
* cancelling out the secret is taken an arbitrary number of times (addressed
3545
* in XXH3_accumulate_512), this collision is very unlikely with random inputs
3546
* and/or proper seeding:
3547
*
3548
* This only has a 1 in 2^63 chance of 8 consecutive bytes cancelling out, in a
3549
* function that is only called up to 16 times per hash with up to 240 bytes of
3550
* input.
3551
*
3552
* This is not too bad for a non-cryptographic hash function, especially with
3553
* only 64 bit outputs.
3554
*
3555
* The 128-bit variant (which trades some speed for strength) is NOT affected
3556
* by this, although it is always a good idea to use a proper seed if you care
3557
* about strength.
3558
*/
3559
XXH_FORCE_INLINE xxh_u64 XXH3_mix16B(const xxh_u8* XXH_RESTRICT input,
3560
const xxh_u8* XXH_RESTRICT secret, xxh_u64 seed64)
3561
{
3562
#if defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
3563
&& defined(__i386__) && defined(__SSE2__) /* x86 + SSE2 */ \
3564
&& !defined(XXH_ENABLE_AUTOVECTORIZE) /* Define to disable like XXH32 hack */
3565
/*
3566
* UGLY HACK:
3567
* GCC for x86 tends to autovectorize the 128-bit multiply, resulting in
3568
* slower code.
3569
*
3570
* By forcing seed64 into a register, we disrupt the cost model and
3571
* cause it to scalarize. See `XXH32_round()`
3572
*
3573
* FIXME: Clang's output is still _much_ faster -- On an AMD Ryzen 3600,
3574
* XXH3_64bits @ len=240 runs at 4.6 GB/s with Clang 9, but 3.3 GB/s on
3575
* GCC 9.2, despite both emitting scalar code.
3576
*
3577
* GCC generates much better scalar code than Clang for the rest of XXH3,
3578
* which is why finding a more optimal codepath is an interest.
3579
*/
3580
XXH_COMPILER_GUARD(seed64);
3581
#endif
3582
{ xxh_u64 const input_lo = XXH_readLE64(input);
3583
xxh_u64 const input_hi = XXH_readLE64(input+8);
3584
return XXH3_mul128_fold64(
3585
input_lo ^ (XXH_readLE64(secret) + seed64),
3586
input_hi ^ (XXH_readLE64(secret+8) - seed64)
3587
);
3588
}
3589
}
3590
3591
/* For mid range keys, XXH3 uses a Mum-hash variant. */
3592
XXH_FORCE_INLINE XXH64_hash_t
3593
XXH3_len_17to128_64b(const xxh_u8* XXH_RESTRICT input, size_t len,
3594
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
3595
XXH64_hash_t seed)
3596
{
3597
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
3598
XXH_ASSERT(16 < len && len <= 128);
3599
3600
{ xxh_u64 acc = len * XXH_PRIME64_1;
3601
if (len > 32) {
3602
if (len > 64) {
3603
if (len > 96) {
3604
acc += XXH3_mix16B(input+48, secret+96, seed);
3605
acc += XXH3_mix16B(input+len-64, secret+112, seed);
3606
}
3607
acc += XXH3_mix16B(input+32, secret+64, seed);
3608
acc += XXH3_mix16B(input+len-48, secret+80, seed);
3609
}
3610
acc += XXH3_mix16B(input+16, secret+32, seed);
3611
acc += XXH3_mix16B(input+len-32, secret+48, seed);
3612
}
3613
acc += XXH3_mix16B(input+0, secret+0, seed);
3614
acc += XXH3_mix16B(input+len-16, secret+16, seed);
3615
3616
return XXH3_avalanche(acc);
3617
}
3618
}
3619
3620
#define XXH3_MIDSIZE_MAX 240
3621
3622
XXH_NO_INLINE XXH64_hash_t
3623
XXH3_len_129to240_64b(const xxh_u8* XXH_RESTRICT input, size_t len,
3624
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
3625
XXH64_hash_t seed)
3626
{
3627
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
3628
XXH_ASSERT(128 < len && len <= XXH3_MIDSIZE_MAX);
3629
3630
#define XXH3_MIDSIZE_STARTOFFSET 3
3631
#define XXH3_MIDSIZE_LASTOFFSET 17
3632
3633
{ xxh_u64 acc = len * XXH_PRIME64_1;
3634
int const nbRounds = (int)len / 16;
3635
int i;
3636
for (i=0; i<8; i++) {
3637
acc += XXH3_mix16B(input+(16*i), secret+(16*i), seed);
3638
}
3639
acc = XXH3_avalanche(acc);
3640
XXH_ASSERT(nbRounds >= 8);
3641
#if defined(__clang__) /* Clang */ \
3642
&& (defined(__ARM_NEON) || defined(__ARM_NEON__)) /* NEON */ \
3643
&& !defined(XXH_ENABLE_AUTOVECTORIZE) /* Define to disable */
3644
/*
3645
* UGLY HACK:
3646
* Clang for ARMv7-A tries to vectorize this loop, similar to GCC x86.
3647
* In everywhere else, it uses scalar code.
3648
*
3649
* For 64->128-bit multiplies, even if the NEON was 100% optimal, it
3650
* would still be slower than UMAAL (see XXH_mult64to128).
3651
*
3652
* Unfortunately, Clang doesn't handle the long multiplies properly and
3653
* converts them to the nonexistent "vmulq_u64" intrinsic, which is then
3654
* scalarized into an ugly mess of VMOV.32 instructions.
3655
*
3656
* This mess is difficult to avoid without turning autovectorization
3657
* off completely, but they are usually relatively minor and/or not
3658
* worth it to fix.
3659
*
3660
* This loop is the easiest to fix, as unlike XXH32, this pragma
3661
* _actually works_ because it is a loop vectorization instead of an
3662
* SLP vectorization.
3663
*/
3664
#pragma clang loop vectorize(disable)
3665
#endif
3666
for (i=8 ; i < nbRounds; i++) {
3667
acc += XXH3_mix16B(input+(16*i), secret+(16*(i-8)) + XXH3_MIDSIZE_STARTOFFSET, seed);
3668
}
3669
/* last bytes */
3670
acc += XXH3_mix16B(input + len - 16, secret + XXH3_SECRET_SIZE_MIN - XXH3_MIDSIZE_LASTOFFSET, seed);
3671
return XXH3_avalanche(acc);
3672
}
3673
}
3674
3675
3676
/* ======= Long Keys ======= */
3677
3678
#define XXH_STRIPE_LEN 64
3679
#define XXH_SECRET_CONSUME_RATE 8 /* nb of secret bytes consumed at each accumulation */
3680
#define XXH_ACC_NB (XXH_STRIPE_LEN / sizeof(xxh_u64))
3681
3682
#ifdef XXH_OLD_NAMES
3683
# define STRIPE_LEN XXH_STRIPE_LEN
3684
# define ACC_NB XXH_ACC_NB
3685
#endif
3686
3687
XXH_FORCE_INLINE void XXH_writeLE64(void* dst, xxh_u64 v64)
3688
{
3689
if (!XXH_CPU_LITTLE_ENDIAN) v64 = XXH_swap64(v64);
3690
XXH_memcpy(dst, &v64, sizeof(v64));
3691
}
3692
3693
/* Several intrinsic functions below are supposed to accept __int64 as argument,
3694
* as documented in https://software.intel.com/sites/landingpage/IntrinsicsGuide/ .
3695
* However, several environments do not define __int64 type,
3696
* requiring a workaround.
3697
*/
3698
#if !defined (__VMS) \
3699
&& (defined (__cplusplus) \
3700
|| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
3701
typedef int64_t xxh_i64;
3702
#else
3703
/* the following type must have a width of 64-bit */
3704
typedef long long xxh_i64;
3705
#endif
3706
3707
3708
/*
3709
* XXH3_accumulate_512 is the tightest loop for long inputs, and it is the most optimized.
3710
*
3711
* It is a hardened version of UMAC, based off of FARSH's implementation.
3712
*
3713
* This was chosen because it adapts quite well to 32-bit, 64-bit, and SIMD
3714
* implementations, and it is ridiculously fast.
3715
*
3716
* We harden it by mixing the original input to the accumulators as well as the product.
3717
*
3718
* This means that in the (relatively likely) case of a multiply by zero, the
3719
* original input is preserved.
3720
*
3721
* On 128-bit inputs, we swap 64-bit pairs when we add the input to improve
3722
* cross-pollination, as otherwise the upper and lower halves would be
3723
* essentially independent.
3724
*
3725
* This doesn't matter on 64-bit hashes since they all get merged together in
3726
* the end, so we skip the extra step.
3727
*
3728
* Both XXH3_64bits and XXH3_128bits use this subroutine.
3729
*/
3730
3731
#if (XXH_VECTOR == XXH_AVX512) \
3732
|| (defined(XXH_DISPATCH_AVX512) && XXH_DISPATCH_AVX512 != 0)
3733
3734
#ifndef XXH_TARGET_AVX512
3735
# define XXH_TARGET_AVX512 /* disable attribute target */
3736
#endif
3737
3738
XXH_FORCE_INLINE XXH_TARGET_AVX512 void
3739
XXH3_accumulate_512_avx512(void* XXH_RESTRICT acc,
3740
const void* XXH_RESTRICT input,
3741
const void* XXH_RESTRICT secret)
3742
{
3743
__m512i* const xacc = (__m512i *) acc;
3744
XXH_ASSERT((((size_t)acc) & 63) == 0);
3745
XXH_STATIC_ASSERT(XXH_STRIPE_LEN == sizeof(__m512i));
3746
3747
{
3748
/* data_vec = input[0]; */
3749
__m512i const data_vec = _mm512_loadu_si512 (input);
3750
/* key_vec = secret[0]; */
3751
__m512i const key_vec = _mm512_loadu_si512 (secret);
3752
/* data_key = data_vec ^ key_vec; */
3753
__m512i const data_key = _mm512_xor_si512 (data_vec, key_vec);
3754
/* data_key_lo = data_key >> 32; */
3755
__m512i const data_key_lo = _mm512_shuffle_epi32 (data_key, (_MM_PERM_ENUM)_MM_SHUFFLE(0, 3, 0, 1));
3756
/* product = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3757
__m512i const product = _mm512_mul_epu32 (data_key, data_key_lo);
3758
/* xacc[0] += swap(data_vec); */
3759
__m512i const data_swap = _mm512_shuffle_epi32(data_vec, (_MM_PERM_ENUM)_MM_SHUFFLE(1, 0, 3, 2));
3760
__m512i const sum = _mm512_add_epi64(*xacc, data_swap);
3761
/* xacc[0] += product; */
3762
*xacc = _mm512_add_epi64(product, sum);
3763
}
3764
}
3765
3766
/*
3767
* XXH3_scrambleAcc: Scrambles the accumulators to improve mixing.
3768
*
3769
* Multiplication isn't perfect, as explained by Google in HighwayHash:
3770
*
3771
* // Multiplication mixes/scrambles bytes 0-7 of the 64-bit result to
3772
* // varying degrees. In descending order of goodness, bytes
3773
* // 3 4 2 5 1 6 0 7 have quality 228 224 164 160 100 96 36 32.
3774
* // As expected, the upper and lower bytes are much worse.
3775
*
3776
* Source: https://github.com/google/highwayhash/blob/0aaf66b/highwayhash/hh_avx2.h#L291
3777
*
3778
* Since our algorithm uses a pseudorandom secret to add some variance into the
3779
* mix, we don't need to (or want to) mix as often or as much as HighwayHash does.
3780
*
3781
* This isn't as tight as XXH3_accumulate, but still written in SIMD to avoid
3782
* extraction.
3783
*
3784
* Both XXH3_64bits and XXH3_128bits use this subroutine.
3785
*/
3786
3787
XXH_FORCE_INLINE XXH_TARGET_AVX512 void
3788
XXH3_scrambleAcc_avx512(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3789
{
3790
XXH_ASSERT((((size_t)acc) & 63) == 0);
3791
XXH_STATIC_ASSERT(XXH_STRIPE_LEN == sizeof(__m512i));
3792
{ __m512i* const xacc = (__m512i*) acc;
3793
const __m512i prime32 = _mm512_set1_epi32((int)XXH_PRIME32_1);
3794
3795
/* xacc[0] ^= (xacc[0] >> 47) */
3796
__m512i const acc_vec = *xacc;
3797
__m512i const shifted = _mm512_srli_epi64 (acc_vec, 47);
3798
__m512i const data_vec = _mm512_xor_si512 (acc_vec, shifted);
3799
/* xacc[0] ^= secret; */
3800
__m512i const key_vec = _mm512_loadu_si512 (secret);
3801
__m512i const data_key = _mm512_xor_si512 (data_vec, key_vec);
3802
3803
/* xacc[0] *= XXH_PRIME32_1; */
3804
__m512i const data_key_hi = _mm512_shuffle_epi32 (data_key, (_MM_PERM_ENUM)_MM_SHUFFLE(0, 3, 0, 1));
3805
__m512i const prod_lo = _mm512_mul_epu32 (data_key, prime32);
3806
__m512i const prod_hi = _mm512_mul_epu32 (data_key_hi, prime32);
3807
*xacc = _mm512_add_epi64(prod_lo, _mm512_slli_epi64(prod_hi, 32));
3808
}
3809
}
3810
3811
XXH_FORCE_INLINE XXH_TARGET_AVX512 void
3812
XXH3_initCustomSecret_avx512(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
3813
{
3814
XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 63) == 0);
3815
XXH_STATIC_ASSERT(XXH_SEC_ALIGN == 64);
3816
XXH_ASSERT(((size_t)customSecret & 63) == 0);
3817
(void)(&XXH_writeLE64);
3818
{ int const nbRounds = XXH_SECRET_DEFAULT_SIZE / sizeof(__m512i);
3819
__m512i const seed = _mm512_mask_set1_epi64(_mm512_set1_epi64((xxh_i64)seed64), 0xAA, (xxh_i64)(0U - seed64));
3820
3821
const __m512i* const src = (const __m512i*) ((const void*) XXH3_kSecret);
3822
__m512i* const dest = ( __m512i*) customSecret;
3823
int i;
3824
XXH_ASSERT(((size_t)src & 63) == 0); /* control alignment */
3825
XXH_ASSERT(((size_t)dest & 63) == 0);
3826
for (i=0; i < nbRounds; ++i) {
3827
/* GCC has a bug, _mm512_stream_load_si512 accepts 'void*', not 'void const*',
3828
* this will warn "discards 'const' qualifier". */
3829
union {
3830
const __m512i* cp;
3831
void* p;
3832
} remote_const_void;
3833
remote_const_void.cp = src + i;
3834
dest[i] = _mm512_add_epi64(_mm512_stream_load_si512(remote_const_void.p), seed);
3835
} }
3836
}
3837
3838
#endif
3839
3840
#if (XXH_VECTOR == XXH_AVX2) \
3841
|| (defined(XXH_DISPATCH_AVX2) && XXH_DISPATCH_AVX2 != 0)
3842
3843
#ifndef XXH_TARGET_AVX2
3844
# define XXH_TARGET_AVX2 /* disable attribute target */
3845
#endif
3846
3847
XXH_FORCE_INLINE XXH_TARGET_AVX2 void
3848
XXH3_accumulate_512_avx2( void* XXH_RESTRICT acc,
3849
const void* XXH_RESTRICT input,
3850
const void* XXH_RESTRICT secret)
3851
{
3852
XXH_ASSERT((((size_t)acc) & 31) == 0);
3853
{ __m256i* const xacc = (__m256i *) acc;
3854
/* Unaligned. This is mainly for pointer arithmetic, and because
3855
* _mm256_loadu_si256 requires a const __m256i * pointer for some reason. */
3856
const __m256i* const xinput = (const __m256i *) input;
3857
/* Unaligned. This is mainly for pointer arithmetic, and because
3858
* _mm256_loadu_si256 requires a const __m256i * pointer for some reason. */
3859
const __m256i* const xsecret = (const __m256i *) secret;
3860
3861
size_t i;
3862
for (i=0; i < XXH_STRIPE_LEN/sizeof(__m256i); i++) {
3863
/* data_vec = xinput[i]; */
3864
__m256i const data_vec = _mm256_loadu_si256 (xinput+i);
3865
/* key_vec = xsecret[i]; */
3866
__m256i const key_vec = _mm256_loadu_si256 (xsecret+i);
3867
/* data_key = data_vec ^ key_vec; */
3868
__m256i const data_key = _mm256_xor_si256 (data_vec, key_vec);
3869
/* data_key_lo = data_key >> 32; */
3870
__m256i const data_key_lo = _mm256_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3871
/* product = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3872
__m256i const product = _mm256_mul_epu32 (data_key, data_key_lo);
3873
/* xacc[i] += swap(data_vec); */
3874
__m256i const data_swap = _mm256_shuffle_epi32(data_vec, _MM_SHUFFLE(1, 0, 3, 2));
3875
__m256i const sum = _mm256_add_epi64(xacc[i], data_swap);
3876
/* xacc[i] += product; */
3877
xacc[i] = _mm256_add_epi64(product, sum);
3878
} }
3879
}
3880
3881
XXH_FORCE_INLINE XXH_TARGET_AVX2 void
3882
XXH3_scrambleAcc_avx2(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3883
{
3884
XXH_ASSERT((((size_t)acc) & 31) == 0);
3885
{ __m256i* const xacc = (__m256i*) acc;
3886
/* Unaligned. This is mainly for pointer arithmetic, and because
3887
* _mm256_loadu_si256 requires a const __m256i * pointer for some reason. */
3888
const __m256i* const xsecret = (const __m256i *) secret;
3889
const __m256i prime32 = _mm256_set1_epi32((int)XXH_PRIME32_1);
3890
3891
size_t i;
3892
for (i=0; i < XXH_STRIPE_LEN/sizeof(__m256i); i++) {
3893
/* xacc[i] ^= (xacc[i] >> 47) */
3894
__m256i const acc_vec = xacc[i];
3895
__m256i const shifted = _mm256_srli_epi64 (acc_vec, 47);
3896
__m256i const data_vec = _mm256_xor_si256 (acc_vec, shifted);
3897
/* xacc[i] ^= xsecret; */
3898
__m256i const key_vec = _mm256_loadu_si256 (xsecret+i);
3899
__m256i const data_key = _mm256_xor_si256 (data_vec, key_vec);
3900
3901
/* xacc[i] *= XXH_PRIME32_1; */
3902
__m256i const data_key_hi = _mm256_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3903
__m256i const prod_lo = _mm256_mul_epu32 (data_key, prime32);
3904
__m256i const prod_hi = _mm256_mul_epu32 (data_key_hi, prime32);
3905
xacc[i] = _mm256_add_epi64(prod_lo, _mm256_slli_epi64(prod_hi, 32));
3906
}
3907
}
3908
}
3909
3910
XXH_FORCE_INLINE XXH_TARGET_AVX2 void XXH3_initCustomSecret_avx2(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
3911
{
3912
XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 31) == 0);
3913
XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE / sizeof(__m256i)) == 6);
3914
XXH_STATIC_ASSERT(XXH_SEC_ALIGN <= 64);
3915
(void)(&XXH_writeLE64);
3916
XXH_PREFETCH(customSecret);
3917
{ __m256i const seed = _mm256_set_epi64x((xxh_i64)(0U - seed64), (xxh_i64)seed64, (xxh_i64)(0U - seed64), (xxh_i64)seed64);
3918
3919
const __m256i* const src = (const __m256i*) ((const void*) XXH3_kSecret);
3920
__m256i* dest = ( __m256i*) customSecret;
3921
3922
# if defined(__GNUC__) || defined(__clang__)
3923
/*
3924
* On GCC & Clang, marking 'dest' as modified will cause the compiler:
3925
* - do not extract the secret from sse registers in the internal loop
3926
* - use less common registers, and avoid pushing these reg into stack
3927
*/
3928
XXH_COMPILER_GUARD(dest);
3929
# endif
3930
XXH_ASSERT(((size_t)src & 31) == 0); /* control alignment */
3931
XXH_ASSERT(((size_t)dest & 31) == 0);
3932
3933
/* GCC -O2 need unroll loop manually */
3934
dest[0] = _mm256_add_epi64(_mm256_stream_load_si256(src+0), seed);
3935
dest[1] = _mm256_add_epi64(_mm256_stream_load_si256(src+1), seed);
3936
dest[2] = _mm256_add_epi64(_mm256_stream_load_si256(src+2), seed);
3937
dest[3] = _mm256_add_epi64(_mm256_stream_load_si256(src+3), seed);
3938
dest[4] = _mm256_add_epi64(_mm256_stream_load_si256(src+4), seed);
3939
dest[5] = _mm256_add_epi64(_mm256_stream_load_si256(src+5), seed);
3940
}
3941
}
3942
3943
#endif
3944
3945
/* x86dispatch always generates SSE2 */
3946
#if (XXH_VECTOR == XXH_SSE2) || defined(XXH_X86DISPATCH)
3947
3948
#ifndef XXH_TARGET_SSE2
3949
# define XXH_TARGET_SSE2 /* disable attribute target */
3950
#endif
3951
3952
XXH_FORCE_INLINE XXH_TARGET_SSE2 void
3953
XXH3_accumulate_512_sse2( void* XXH_RESTRICT acc,
3954
const void* XXH_RESTRICT input,
3955
const void* XXH_RESTRICT secret)
3956
{
3957
/* SSE2 is just a half-scale version of the AVX2 version. */
3958
XXH_ASSERT((((size_t)acc) & 15) == 0);
3959
{ __m128i* const xacc = (__m128i *) acc;
3960
/* Unaligned. This is mainly for pointer arithmetic, and because
3961
* _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3962
const __m128i* const xinput = (const __m128i *) input;
3963
/* Unaligned. This is mainly for pointer arithmetic, and because
3964
* _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3965
const __m128i* const xsecret = (const __m128i *) secret;
3966
3967
size_t i;
3968
for (i=0; i < XXH_STRIPE_LEN/sizeof(__m128i); i++) {
3969
/* data_vec = xinput[i]; */
3970
__m128i const data_vec = _mm_loadu_si128 (xinput+i);
3971
/* key_vec = xsecret[i]; */
3972
__m128i const key_vec = _mm_loadu_si128 (xsecret+i);
3973
/* data_key = data_vec ^ key_vec; */
3974
__m128i const data_key = _mm_xor_si128 (data_vec, key_vec);
3975
/* data_key_lo = data_key >> 32; */
3976
__m128i const data_key_lo = _mm_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3977
/* product = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3978
__m128i const product = _mm_mul_epu32 (data_key, data_key_lo);
3979
/* xacc[i] += swap(data_vec); */
3980
__m128i const data_swap = _mm_shuffle_epi32(data_vec, _MM_SHUFFLE(1,0,3,2));
3981
__m128i const sum = _mm_add_epi64(xacc[i], data_swap);
3982
/* xacc[i] += product; */
3983
xacc[i] = _mm_add_epi64(product, sum);
3984
} }
3985
}
3986
3987
XXH_FORCE_INLINE XXH_TARGET_SSE2 void
3988
XXH3_scrambleAcc_sse2(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3989
{
3990
XXH_ASSERT((((size_t)acc) & 15) == 0);
3991
{ __m128i* const xacc = (__m128i*) acc;
3992
/* Unaligned. This is mainly for pointer arithmetic, and because
3993
* _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3994
const __m128i* const xsecret = (const __m128i *) secret;
3995
const __m128i prime32 = _mm_set1_epi32((int)XXH_PRIME32_1);
3996
3997
size_t i;
3998
for (i=0; i < XXH_STRIPE_LEN/sizeof(__m128i); i++) {
3999
/* xacc[i] ^= (xacc[i] >> 47) */
4000
__m128i const acc_vec = xacc[i];
4001
__m128i const shifted = _mm_srli_epi64 (acc_vec, 47);
4002
__m128i const data_vec = _mm_xor_si128 (acc_vec, shifted);
4003
/* xacc[i] ^= xsecret[i]; */
4004
__m128i const key_vec = _mm_loadu_si128 (xsecret+i);
4005
__m128i const data_key = _mm_xor_si128 (data_vec, key_vec);
4006
4007
/* xacc[i] *= XXH_PRIME32_1; */
4008
__m128i const data_key_hi = _mm_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
4009
__m128i const prod_lo = _mm_mul_epu32 (data_key, prime32);
4010
__m128i const prod_hi = _mm_mul_epu32 (data_key_hi, prime32);
4011
xacc[i] = _mm_add_epi64(prod_lo, _mm_slli_epi64(prod_hi, 32));
4012
}
4013
}
4014
}
4015
4016
XXH_FORCE_INLINE XXH_TARGET_SSE2 void XXH3_initCustomSecret_sse2(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
4017
{
4018
XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 15) == 0);
4019
(void)(&XXH_writeLE64);
4020
{ int const nbRounds = XXH_SECRET_DEFAULT_SIZE / sizeof(__m128i);
4021
4022
# if defined(_MSC_VER) && defined(_M_IX86) && _MSC_VER < 1900
4023
/* MSVC 32bit mode does not support _mm_set_epi64x before 2015 */
4024
XXH_ALIGN(16) const xxh_i64 seed64x2[2] = { (xxh_i64)seed64, (xxh_i64)(0U - seed64) };
4025
__m128i const seed = _mm_load_si128((__m128i const*)seed64x2);
4026
# else
4027
__m128i const seed = _mm_set_epi64x((xxh_i64)(0U - seed64), (xxh_i64)seed64);
4028
# endif
4029
int i;
4030
4031
const void* const src16 = XXH3_kSecret;
4032
__m128i* dst16 = (__m128i*) customSecret;
4033
# if defined(__GNUC__) || defined(__clang__)
4034
/*
4035
* On GCC & Clang, marking 'dest' as modified will cause the compiler:
4036
* - do not extract the secret from sse registers in the internal loop
4037
* - use less common registers, and avoid pushing these reg into stack
4038
*/
4039
XXH_COMPILER_GUARD(dst16);
4040
# endif
4041
XXH_ASSERT(((size_t)src16 & 15) == 0); /* control alignment */
4042
XXH_ASSERT(((size_t)dst16 & 15) == 0);
4043
4044
for (i=0; i < nbRounds; ++i) {
4045
dst16[i] = _mm_add_epi64(_mm_load_si128((const __m128i *)src16+i), seed);
4046
} }
4047
}
4048
4049
#endif
4050
4051
#if (XXH_VECTOR == XXH_NEON)
4052
4053
/* forward declarations for the scalar routines */
4054
XXH_FORCE_INLINE void
4055
XXH3_scalarRound(void* XXH_RESTRICT acc, void const* XXH_RESTRICT input,
4056
void const* XXH_RESTRICT secret, size_t lane);
4057
4058
XXH_FORCE_INLINE void
4059
XXH3_scalarScrambleRound(void* XXH_RESTRICT acc,
4060
void const* XXH_RESTRICT secret, size_t lane);
4061
4062
/*!
4063
* @internal
4064
* @brief The bulk processing loop for NEON.
4065
*
4066
* The NEON code path is actually partially scalar when running on AArch64. This
4067
* is to optimize the pipelining and can have up to 15% speedup depending on the
4068
* CPU, and it also mitigates some GCC codegen issues.
4069
*
4070
* @see XXH3_NEON_LANES for configuring this and details about this optimization.
4071
*/
4072
XXH_FORCE_INLINE void
4073
XXH3_accumulate_512_neon( void* XXH_RESTRICT acc,
4074
const void* XXH_RESTRICT input,
4075
const void* XXH_RESTRICT secret)
4076
{
4077
XXH_ASSERT((((size_t)acc) & 15) == 0);
4078
XXH_STATIC_ASSERT(XXH3_NEON_LANES > 0 && XXH3_NEON_LANES <= XXH_ACC_NB && XXH3_NEON_LANES % 2 == 0);
4079
{
4080
uint64x2_t* const xacc = (uint64x2_t *) acc;
4081
/* We don't use a uint32x4_t pointer because it causes bus errors on ARMv7. */
4082
uint8_t const* const xinput = (const uint8_t *) input;
4083
uint8_t const* const xsecret = (const uint8_t *) secret;
4084
4085
size_t i;
4086
/* NEON for the first few lanes (these loops are normally interleaved) */
4087
for (i=0; i < XXH3_NEON_LANES / 2; i++) {
4088
/* data_vec = xinput[i]; */
4089
uint8x16_t data_vec = vld1q_u8(xinput + (i * 16));
4090
/* key_vec = xsecret[i]; */
4091
uint8x16_t key_vec = vld1q_u8(xsecret + (i * 16));
4092
uint64x2_t data_key;
4093
uint32x2_t data_key_lo, data_key_hi;
4094
/* xacc[i] += swap(data_vec); */
4095
uint64x2_t const data64 = vreinterpretq_u64_u8(data_vec);
4096
uint64x2_t const swapped = vextq_u64(data64, data64, 1);
4097
xacc[i] = vaddq_u64 (xacc[i], swapped);
4098
/* data_key = data_vec ^ key_vec; */
4099
data_key = vreinterpretq_u64_u8(veorq_u8(data_vec, key_vec));
4100
/* data_key_lo = (uint32x2_t) (data_key & 0xFFFFFFFF);
4101
* data_key_hi = (uint32x2_t) (data_key >> 32);
4102
* data_key = UNDEFINED; */
4103
XXH_SPLIT_IN_PLACE(data_key, data_key_lo, data_key_hi);
4104
/* xacc[i] += (uint64x2_t) data_key_lo * (uint64x2_t) data_key_hi; */
4105
xacc[i] = vmlal_u32 (xacc[i], data_key_lo, data_key_hi);
4106
4107
}
4108
/* Scalar for the remainder. This may be a zero iteration loop. */
4109
for (i = XXH3_NEON_LANES; i < XXH_ACC_NB; i++) {
4110
XXH3_scalarRound(acc, input, secret, i);
4111
}
4112
}
4113
}
4114
4115
XXH_FORCE_INLINE void
4116
XXH3_scrambleAcc_neon(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4117
{
4118
XXH_ASSERT((((size_t)acc) & 15) == 0);
4119
4120
{ uint64x2_t* xacc = (uint64x2_t*) acc;
4121
uint8_t const* xsecret = (uint8_t const*) secret;
4122
uint32x2_t prime = vdup_n_u32 (XXH_PRIME32_1);
4123
4124
size_t i;
4125
/* NEON for the first few lanes (these loops are normally interleaved) */
4126
for (i=0; i < XXH3_NEON_LANES / 2; i++) {
4127
/* xacc[i] ^= (xacc[i] >> 47); */
4128
uint64x2_t acc_vec = xacc[i];
4129
uint64x2_t shifted = vshrq_n_u64 (acc_vec, 47);
4130
uint64x2_t data_vec = veorq_u64 (acc_vec, shifted);
4131
4132
/* xacc[i] ^= xsecret[i]; */
4133
uint8x16_t key_vec = vld1q_u8 (xsecret + (i * 16));
4134
uint64x2_t data_key = veorq_u64 (data_vec, vreinterpretq_u64_u8(key_vec));
4135
4136
/* xacc[i] *= XXH_PRIME32_1 */
4137
uint32x2_t data_key_lo, data_key_hi;
4138
/* data_key_lo = (uint32x2_t) (xacc[i] & 0xFFFFFFFF);
4139
* data_key_hi = (uint32x2_t) (xacc[i] >> 32);
4140
* xacc[i] = UNDEFINED; */
4141
XXH_SPLIT_IN_PLACE(data_key, data_key_lo, data_key_hi);
4142
{ /*
4143
* prod_hi = (data_key >> 32) * XXH_PRIME32_1;
4144
*
4145
* Avoid vmul_u32 + vshll_n_u32 since Clang 6 and 7 will
4146
* incorrectly "optimize" this:
4147
* tmp = vmul_u32(vmovn_u64(a), vmovn_u64(b));
4148
* shifted = vshll_n_u32(tmp, 32);
4149
* to this:
4150
* tmp = "vmulq_u64"(a, b); // no such thing!
4151
* shifted = vshlq_n_u64(tmp, 32);
4152
*
4153
* However, unlike SSE, Clang lacks a 64-bit multiply routine
4154
* for NEON, and it scalarizes two 64-bit multiplies instead.
4155
*
4156
* vmull_u32 has the same timing as vmul_u32, and it avoids
4157
* this bug completely.
4158
* See https://bugs.llvm.org/show_bug.cgi?id=39967
4159
*/
4160
uint64x2_t prod_hi = vmull_u32 (data_key_hi, prime);
4161
/* xacc[i] = prod_hi << 32; */
4162
xacc[i] = vshlq_n_u64(prod_hi, 32);
4163
/* xacc[i] += (prod_hi & 0xFFFFFFFF) * XXH_PRIME32_1; */
4164
xacc[i] = vmlal_u32(xacc[i], data_key_lo, prime);
4165
}
4166
}
4167
/* Scalar for the remainder. This may be a zero iteration loop. */
4168
for (i = XXH3_NEON_LANES; i < XXH_ACC_NB; i++) {
4169
XXH3_scalarScrambleRound(acc, secret, i);
4170
}
4171
}
4172
}
4173
4174
#endif
4175
4176
#if (XXH_VECTOR == XXH_VSX)
4177
4178
XXH_FORCE_INLINE void
4179
XXH3_accumulate_512_vsx( void* XXH_RESTRICT acc,
4180
const void* XXH_RESTRICT input,
4181
const void* XXH_RESTRICT secret)
4182
{
4183
/* presumed aligned */
4184
unsigned int* const xacc = (unsigned int*) acc;
4185
xxh_u64x2 const* const xinput = (xxh_u64x2 const*) input; /* no alignment restriction */
4186
xxh_u64x2 const* const xsecret = (xxh_u64x2 const*) secret; /* no alignment restriction */
4187
xxh_u64x2 const v32 = { 32, 32 };
4188
size_t i;
4189
for (i = 0; i < XXH_STRIPE_LEN / sizeof(xxh_u64x2); i++) {
4190
/* data_vec = xinput[i]; */
4191
xxh_u64x2 const data_vec = XXH_vec_loadu(xinput + i);
4192
/* key_vec = xsecret[i]; */
4193
xxh_u64x2 const key_vec = XXH_vec_loadu(xsecret + i);
4194
xxh_u64x2 const data_key = data_vec ^ key_vec;
4195
/* shuffled = (data_key << 32) | (data_key >> 32); */
4196
xxh_u32x4 const shuffled = (xxh_u32x4)vec_rl(data_key, v32);
4197
/* product = ((xxh_u64x2)data_key & 0xFFFFFFFF) * ((xxh_u64x2)shuffled & 0xFFFFFFFF); */
4198
xxh_u64x2 const product = XXH_vec_mulo((xxh_u32x4)data_key, shuffled);
4199
/* acc_vec = xacc[i]; */
4200
xxh_u64x2 acc_vec = (xxh_u64x2)vec_xl(0, xacc + 4 * i);
4201
acc_vec += product;
4202
4203
/* swap high and low halves */
4204
#ifdef __s390x__
4205
acc_vec += vec_permi(data_vec, data_vec, 2);
4206
#else
4207
acc_vec += vec_xxpermdi(data_vec, data_vec, 2);
4208
#endif
4209
/* xacc[i] = acc_vec; */
4210
vec_xst((xxh_u32x4)acc_vec, 0, xacc + 4 * i);
4211
}
4212
}
4213
4214
XXH_FORCE_INLINE void
4215
XXH3_scrambleAcc_vsx(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4216
{
4217
XXH_ASSERT((((size_t)acc) & 15) == 0);
4218
4219
{ xxh_u64x2* const xacc = (xxh_u64x2*) acc;
4220
const xxh_u64x2* const xsecret = (const xxh_u64x2*) secret;
4221
/* constants */
4222
xxh_u64x2 const v32 = { 32, 32 };
4223
xxh_u64x2 const v47 = { 47, 47 };
4224
xxh_u32x4 const prime = { XXH_PRIME32_1, XXH_PRIME32_1, XXH_PRIME32_1, XXH_PRIME32_1 };
4225
size_t i;
4226
for (i = 0; i < XXH_STRIPE_LEN / sizeof(xxh_u64x2); i++) {
4227
/* xacc[i] ^= (xacc[i] >> 47); */
4228
xxh_u64x2 const acc_vec = xacc[i];
4229
xxh_u64x2 const data_vec = acc_vec ^ (acc_vec >> v47);
4230
4231
/* xacc[i] ^= xsecret[i]; */
4232
xxh_u64x2 const key_vec = XXH_vec_loadu(xsecret + i);
4233
xxh_u64x2 const data_key = data_vec ^ key_vec;
4234
4235
/* xacc[i] *= XXH_PRIME32_1 */
4236
/* prod_lo = ((xxh_u64x2)data_key & 0xFFFFFFFF) * ((xxh_u64x2)prime & 0xFFFFFFFF); */
4237
xxh_u64x2 const prod_even = XXH_vec_mule((xxh_u32x4)data_key, prime);
4238
/* prod_hi = ((xxh_u64x2)data_key >> 32) * ((xxh_u64x2)prime >> 32); */
4239
xxh_u64x2 const prod_odd = XXH_vec_mulo((xxh_u32x4)data_key, prime);
4240
xacc[i] = prod_odd + (prod_even << v32);
4241
} }
4242
}
4243
4244
#endif
4245
4246
/* scalar variants - universal */
4247
4248
/*!
4249
* @internal
4250
* @brief Scalar round for @ref XXH3_accumulate_512_scalar().
4251
*
4252
* This is extracted to its own function because the NEON path uses a combination
4253
* of NEON and scalar.
4254
*/
4255
XXH_FORCE_INLINE void
4256
XXH3_scalarRound(void* XXH_RESTRICT acc,
4257
void const* XXH_RESTRICT input,
4258
void const* XXH_RESTRICT secret,
4259
size_t lane)
4260
{
4261
xxh_u64* xacc = (xxh_u64*) acc;
4262
xxh_u8 const* xinput = (xxh_u8 const*) input;
4263
xxh_u8 const* xsecret = (xxh_u8 const*) secret;
4264
XXH_ASSERT(lane < XXH_ACC_NB);
4265
XXH_ASSERT(((size_t)acc & (XXH_ACC_ALIGN-1)) == 0);
4266
{
4267
xxh_u64 const data_val = XXH_readLE64(xinput + lane * 8);
4268
xxh_u64 const data_key = data_val ^ XXH_readLE64(xsecret + lane * 8);
4269
xacc[lane ^ 1] += data_val; /* swap adjacent lanes */
4270
xacc[lane] += XXH_mult32to64(data_key & 0xFFFFFFFF, data_key >> 32);
4271
}
4272
}
4273
4274
/*!
4275
* @internal
4276
* @brief Processes a 64 byte block of data using the scalar path.
4277
*/
4278
XXH_FORCE_INLINE void
4279
XXH3_accumulate_512_scalar(void* XXH_RESTRICT acc,
4280
const void* XXH_RESTRICT input,
4281
const void* XXH_RESTRICT secret)
4282
{
4283
size_t i;
4284
for (i=0; i < XXH_ACC_NB; i++) {
4285
XXH3_scalarRound(acc, input, secret, i);
4286
}
4287
}
4288
4289
/*!
4290
* @internal
4291
* @brief Scalar scramble step for @ref XXH3_scrambleAcc_scalar().
4292
*
4293
* This is extracted to its own function because the NEON path uses a combination
4294
* of NEON and scalar.
4295
*/
4296
XXH_FORCE_INLINE void
4297
XXH3_scalarScrambleRound(void* XXH_RESTRICT acc,
4298
void const* XXH_RESTRICT secret,
4299
size_t lane)
4300
{
4301
xxh_u64* const xacc = (xxh_u64*) acc; /* presumed aligned */
4302
const xxh_u8* const xsecret = (const xxh_u8*) secret; /* no alignment restriction */
4303
XXH_ASSERT((((size_t)acc) & (XXH_ACC_ALIGN-1)) == 0);
4304
XXH_ASSERT(lane < XXH_ACC_NB);
4305
{
4306
xxh_u64 const key64 = XXH_readLE64(xsecret + lane * 8);
4307
xxh_u64 acc64 = xacc[lane];
4308
acc64 = XXH_xorshift64(acc64, 47);
4309
acc64 ^= key64;
4310
acc64 *= XXH_PRIME32_1;
4311
xacc[lane] = acc64;
4312
}
4313
}
4314
4315
/*!
4316
* @internal
4317
* @brief Scrambles the accumulators after a large chunk has been read
4318
*/
4319
XXH_FORCE_INLINE void
4320
XXH3_scrambleAcc_scalar(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4321
{
4322
size_t i;
4323
for (i=0; i < XXH_ACC_NB; i++) {
4324
XXH3_scalarScrambleRound(acc, secret, i);
4325
}
4326
}
4327
4328
XXH_FORCE_INLINE void
4329
XXH3_initCustomSecret_scalar(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
4330
{
4331
/*
4332
* We need a separate pointer for the hack below,
4333
* which requires a non-const pointer.
4334
* Any decent compiler will optimize this out otherwise.
4335
*/
4336
const xxh_u8* kSecretPtr = XXH3_kSecret;
4337
XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 15) == 0);
4338
4339
#if defined(__clang__) && defined(__aarch64__)
4340
/*
4341
* UGLY HACK:
4342
* Clang generates a bunch of MOV/MOVK pairs for aarch64, and they are
4343
* placed sequentially, in order, at the top of the unrolled loop.
4344
*
4345
* While MOVK is great for generating constants (2 cycles for a 64-bit
4346
* constant compared to 4 cycles for LDR), it fights for bandwidth with
4347
* the arithmetic instructions.
4348
*
4349
* I L S
4350
* MOVK
4351
* MOVK
4352
* MOVK
4353
* MOVK
4354
* ADD
4355
* SUB STR
4356
* STR
4357
* By forcing loads from memory (as the asm line causes Clang to assume
4358
* that XXH3_kSecretPtr has been changed), the pipelines are used more
4359
* efficiently:
4360
* I L S
4361
* LDR
4362
* ADD LDR
4363
* SUB STR
4364
* STR
4365
*
4366
* See XXH3_NEON_LANES for details on the pipsline.
4367
*
4368
* XXH3_64bits_withSeed, len == 256, Snapdragon 835
4369
* without hack: 2654.4 MB/s
4370
* with hack: 3202.9 MB/s
4371
*/
4372
XXH_COMPILER_GUARD(kSecretPtr);
4373
#endif
4374
/*
4375
* Note: in debug mode, this overrides the asm optimization
4376
* and Clang will emit MOVK chains again.
4377
*/
4378
XXH_ASSERT(kSecretPtr == XXH3_kSecret);
4379
4380
{ int const nbRounds = XXH_SECRET_DEFAULT_SIZE / 16;
4381
int i;
4382
for (i=0; i < nbRounds; i++) {
4383
/*
4384
* The asm hack causes Clang to assume that kSecretPtr aliases with
4385
* customSecret, and on aarch64, this prevented LDP from merging two
4386
* loads together for free. Putting the loads together before the stores
4387
* properly generates LDP.
4388
*/
4389
xxh_u64 lo = XXH_readLE64(kSecretPtr + 16*i) + seed64;
4390
xxh_u64 hi = XXH_readLE64(kSecretPtr + 16*i + 8) - seed64;
4391
XXH_writeLE64((xxh_u8*)customSecret + 16*i, lo);
4392
XXH_writeLE64((xxh_u8*)customSecret + 16*i + 8, hi);
4393
} }
4394
}
4395
4396
4397
typedef void (*XXH3_f_accumulate_512)(void* XXH_RESTRICT, const void*, const void*);
4398
typedef void (*XXH3_f_scrambleAcc)(void* XXH_RESTRICT, const void*);
4399
typedef void (*XXH3_f_initCustomSecret)(void* XXH_RESTRICT, xxh_u64);
4400
4401
4402
#if (XXH_VECTOR == XXH_AVX512)
4403
4404
#define XXH3_accumulate_512 XXH3_accumulate_512_avx512
4405
#define XXH3_scrambleAcc XXH3_scrambleAcc_avx512
4406
#define XXH3_initCustomSecret XXH3_initCustomSecret_avx512
4407
4408
#elif (XXH_VECTOR == XXH_AVX2)
4409
4410
#define XXH3_accumulate_512 XXH3_accumulate_512_avx2
4411
#define XXH3_scrambleAcc XXH3_scrambleAcc_avx2
4412
#define XXH3_initCustomSecret XXH3_initCustomSecret_avx2
4413
4414
#elif (XXH_VECTOR == XXH_SSE2)
4415
4416
#define XXH3_accumulate_512 XXH3_accumulate_512_sse2
4417
#define XXH3_scrambleAcc XXH3_scrambleAcc_sse2
4418
#define XXH3_initCustomSecret XXH3_initCustomSecret_sse2
4419
4420
#elif (XXH_VECTOR == XXH_NEON)
4421
4422
#define XXH3_accumulate_512 XXH3_accumulate_512_neon
4423
#define XXH3_scrambleAcc XXH3_scrambleAcc_neon
4424
#define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4425
4426
#elif (XXH_VECTOR == XXH_VSX)
4427
4428
#define XXH3_accumulate_512 XXH3_accumulate_512_vsx
4429
#define XXH3_scrambleAcc XXH3_scrambleAcc_vsx
4430
#define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4431
4432
#else /* scalar */
4433
4434
#define XXH3_accumulate_512 XXH3_accumulate_512_scalar
4435
#define XXH3_scrambleAcc XXH3_scrambleAcc_scalar
4436
#define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4437
4438
#endif
4439
4440
4441
4442
#ifndef XXH_PREFETCH_DIST
4443
# ifdef __clang__
4444
# define XXH_PREFETCH_DIST 320
4445
# else
4446
# if (XXH_VECTOR == XXH_AVX512)
4447
# define XXH_PREFETCH_DIST 512
4448
# else
4449
# define XXH_PREFETCH_DIST 384
4450
# endif
4451
# endif /* __clang__ */
4452
#endif /* XXH_PREFETCH_DIST */
4453
4454
/*
4455
* XXH3_accumulate()
4456
* Loops over XXH3_accumulate_512().
4457
* Assumption: nbStripes will not overflow the secret size
4458
*/
4459
XXH_FORCE_INLINE void
4460
XXH3_accumulate( xxh_u64* XXH_RESTRICT acc,
4461
const xxh_u8* XXH_RESTRICT input,
4462
const xxh_u8* XXH_RESTRICT secret,
4463
size_t nbStripes,
4464
XXH3_f_accumulate_512 f_acc512)
4465
{
4466
size_t n;
4467
for (n = 0; n < nbStripes; n++ ) {
4468
const xxh_u8* const in = input + n*XXH_STRIPE_LEN;
4469
XXH_PREFETCH(in + XXH_PREFETCH_DIST);
4470
f_acc512(acc,
4471
in,
4472
secret + n*XXH_SECRET_CONSUME_RATE);
4473
}
4474
}
4475
4476
XXH_FORCE_INLINE void
4477
XXH3_hashLong_internal_loop(xxh_u64* XXH_RESTRICT acc,
4478
const xxh_u8* XXH_RESTRICT input, size_t len,
4479
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
4480
XXH3_f_accumulate_512 f_acc512,
4481
XXH3_f_scrambleAcc f_scramble)
4482
{
4483
size_t const nbStripesPerBlock = (secretSize - XXH_STRIPE_LEN) / XXH_SECRET_CONSUME_RATE;
4484
size_t const block_len = XXH_STRIPE_LEN * nbStripesPerBlock;
4485
size_t const nb_blocks = (len - 1) / block_len;
4486
4487
size_t n;
4488
4489
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
4490
4491
for (n = 0; n < nb_blocks; n++) {
4492
XXH3_accumulate(acc, input + n*block_len, secret, nbStripesPerBlock, f_acc512);
4493
f_scramble(acc, secret + secretSize - XXH_STRIPE_LEN);
4494
}
4495
4496
/* last partial block */
4497
XXH_ASSERT(len > XXH_STRIPE_LEN);
4498
{ size_t const nbStripes = ((len - 1) - (block_len * nb_blocks)) / XXH_STRIPE_LEN;
4499
XXH_ASSERT(nbStripes <= (secretSize / XXH_SECRET_CONSUME_RATE));
4500
XXH3_accumulate(acc, input + nb_blocks*block_len, secret, nbStripes, f_acc512);
4501
4502
/* last stripe */
4503
{ const xxh_u8* const p = input + len - XXH_STRIPE_LEN;
4504
#define XXH_SECRET_LASTACC_START 7 /* not aligned on 8, last secret is different from acc & scrambler */
4505
f_acc512(acc, p, secret + secretSize - XXH_STRIPE_LEN - XXH_SECRET_LASTACC_START);
4506
} }
4507
}
4508
4509
XXH_FORCE_INLINE xxh_u64
4510
XXH3_mix2Accs(const xxh_u64* XXH_RESTRICT acc, const xxh_u8* XXH_RESTRICT secret)
4511
{
4512
return XXH3_mul128_fold64(
4513
acc[0] ^ XXH_readLE64(secret),
4514
acc[1] ^ XXH_readLE64(secret+8) );
4515
}
4516
4517
static XXH64_hash_t
4518
XXH3_mergeAccs(const xxh_u64* XXH_RESTRICT acc, const xxh_u8* XXH_RESTRICT secret, xxh_u64 start)
4519
{
4520
xxh_u64 result64 = start;
4521
size_t i = 0;
4522
4523
for (i = 0; i < 4; i++) {
4524
result64 += XXH3_mix2Accs(acc+2*i, secret + 16*i);
4525
#if defined(__clang__) /* Clang */ \
4526
&& (defined(__arm__) || defined(__thumb__)) /* ARMv7 */ \
4527
&& (defined(__ARM_NEON) || defined(__ARM_NEON__)) /* NEON */ \
4528
&& !defined(XXH_ENABLE_AUTOVECTORIZE) /* Define to disable */
4529
/*
4530
* UGLY HACK:
4531
* Prevent autovectorization on Clang ARMv7-a. Exact same problem as
4532
* the one in XXH3_len_129to240_64b. Speeds up shorter keys > 240b.
4533
* XXH3_64bits, len == 256, Snapdragon 835:
4534
* without hack: 2063.7 MB/s
4535
* with hack: 2560.7 MB/s
4536
*/
4537
XXH_COMPILER_GUARD(result64);
4538
#endif
4539
}
4540
4541
return XXH3_avalanche(result64);
4542
}
4543
4544
#define XXH3_INIT_ACC { XXH_PRIME32_3, XXH_PRIME64_1, XXH_PRIME64_2, XXH_PRIME64_3, \
4545
XXH_PRIME64_4, XXH_PRIME32_2, XXH_PRIME64_5, XXH_PRIME32_1 }
4546
4547
XXH_FORCE_INLINE XXH64_hash_t
4548
XXH3_hashLong_64b_internal(const void* XXH_RESTRICT input, size_t len,
4549
const void* XXH_RESTRICT secret, size_t secretSize,
4550
XXH3_f_accumulate_512 f_acc512,
4551
XXH3_f_scrambleAcc f_scramble)
4552
{
4553
XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[XXH_ACC_NB] = XXH3_INIT_ACC;
4554
4555
XXH3_hashLong_internal_loop(acc, (const xxh_u8*)input, len, (const xxh_u8*)secret, secretSize, f_acc512, f_scramble);
4556
4557
/* converge into final hash */
4558
XXH_STATIC_ASSERT(sizeof(acc) == 64);
4559
/* do not align on 8, so that the secret is different from the accumulator */
4560
#define XXH_SECRET_MERGEACCS_START 11
4561
XXH_ASSERT(secretSize >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
4562
return XXH3_mergeAccs(acc, (const xxh_u8*)secret + XXH_SECRET_MERGEACCS_START, (xxh_u64)len * XXH_PRIME64_1);
4563
}
4564
4565
/*
4566
* It's important for performance to transmit secret's size (when it's static)
4567
* so that the compiler can properly optimize the vectorized loop.
4568
* This makes a big performance difference for "medium" keys (<1 KB) when using AVX instruction set.
4569
*/
4570
XXH_FORCE_INLINE XXH64_hash_t
4571
XXH3_hashLong_64b_withSecret(const void* XXH_RESTRICT input, size_t len,
4572
XXH64_hash_t seed64, const xxh_u8* XXH_RESTRICT secret, size_t secretLen)
4573
{
4574
(void)seed64;
4575
return XXH3_hashLong_64b_internal(input, len, secret, secretLen, XXH3_accumulate_512, XXH3_scrambleAcc);
4576
}
4577
4578
/*
4579
* It's preferable for performance that XXH3_hashLong is not inlined,
4580
* as it results in a smaller function for small data, easier to the instruction cache.
4581
* Note that inside this no_inline function, we do inline the internal loop,
4582
* and provide a statically defined secret size to allow optimization of vector loop.
4583
*/
4584
XXH_NO_INLINE XXH64_hash_t
4585
XXH3_hashLong_64b_default(const void* XXH_RESTRICT input, size_t len,
4586
XXH64_hash_t seed64, const xxh_u8* XXH_RESTRICT secret, size_t secretLen)
4587
{
4588
(void)seed64; (void)secret; (void)secretLen;
4589
return XXH3_hashLong_64b_internal(input, len, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_accumulate_512, XXH3_scrambleAcc);
4590
}
4591
4592
/*
4593
* XXH3_hashLong_64b_withSeed():
4594
* Generate a custom key based on alteration of default XXH3_kSecret with the seed,
4595
* and then use this key for long mode hashing.
4596
*
4597
* This operation is decently fast but nonetheless costs a little bit of time.
4598
* Try to avoid it whenever possible (typically when seed==0).
4599
*
4600
* It's important for performance that XXH3_hashLong is not inlined. Not sure
4601
* why (uop cache maybe?), but the difference is large and easily measurable.
4602
*/
4603
XXH_FORCE_INLINE XXH64_hash_t
4604
XXH3_hashLong_64b_withSeed_internal(const void* input, size_t len,
4605
XXH64_hash_t seed,
4606
XXH3_f_accumulate_512 f_acc512,
4607
XXH3_f_scrambleAcc f_scramble,
4608
XXH3_f_initCustomSecret f_initSec)
4609
{
4610
if (seed == 0)
4611
return XXH3_hashLong_64b_internal(input, len,
4612
XXH3_kSecret, sizeof(XXH3_kSecret),
4613
f_acc512, f_scramble);
4614
{ XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
4615
f_initSec(secret, seed);
4616
return XXH3_hashLong_64b_internal(input, len, secret, sizeof(secret),
4617
f_acc512, f_scramble);
4618
}
4619
}
4620
4621
/*
4622
* It's important for performance that XXH3_hashLong is not inlined.
4623
*/
4624
XXH_NO_INLINE XXH64_hash_t
4625
XXH3_hashLong_64b_withSeed(const void* input, size_t len,
4626
XXH64_hash_t seed, const xxh_u8* secret, size_t secretLen)
4627
{
4628
(void)secret; (void)secretLen;
4629
return XXH3_hashLong_64b_withSeed_internal(input, len, seed,
4630
XXH3_accumulate_512, XXH3_scrambleAcc, XXH3_initCustomSecret);
4631
}
4632
4633
4634
typedef XXH64_hash_t (*XXH3_hashLong64_f)(const void* XXH_RESTRICT, size_t,
4635
XXH64_hash_t, const xxh_u8* XXH_RESTRICT, size_t);
4636
4637
XXH_FORCE_INLINE XXH64_hash_t
4638
XXH3_64bits_internal(const void* XXH_RESTRICT input, size_t len,
4639
XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen,
4640
XXH3_hashLong64_f f_hashLong)
4641
{
4642
XXH_ASSERT(secretLen >= XXH3_SECRET_SIZE_MIN);
4643
/*
4644
* If an action is to be taken if `secretLen` condition is not respected,
4645
* it should be done here.
4646
* For now, it's a contract pre-condition.
4647
* Adding a check and a branch here would cost performance at every hash.
4648
* Also, note that function signature doesn't offer room to return an error.
4649
*/
4650
if (len <= 16)
4651
return XXH3_len_0to16_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, seed64);
4652
if (len <= 128)
4653
return XXH3_len_17to128_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
4654
if (len <= XXH3_MIDSIZE_MAX)
4655
return XXH3_len_129to240_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
4656
return f_hashLong(input, len, seed64, (const xxh_u8*)secret, secretLen);
4657
}
4658
4659
4660
/* === Public entry point === */
4661
4662
/*! @ingroup xxh3_family */
4663
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits(const void* input, size_t len)
4664
{
4665
return XXH3_64bits_internal(input, len, 0, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_hashLong_64b_default);
4666
}
4667
4668
/*! @ingroup xxh3_family */
4669
XXH_PUBLIC_API XXH64_hash_t
4670
XXH3_64bits_withSecret(const void* input, size_t len, const void* secret, size_t secretSize)
4671
{
4672
return XXH3_64bits_internal(input, len, 0, secret, secretSize, XXH3_hashLong_64b_withSecret);
4673
}
4674
4675
/*! @ingroup xxh3_family */
4676
XXH_PUBLIC_API XXH64_hash_t
4677
XXH3_64bits_withSeed(const void* input, size_t len, XXH64_hash_t seed)
4678
{
4679
return XXH3_64bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_hashLong_64b_withSeed);
4680
}
4681
4682
XXH_PUBLIC_API XXH64_hash_t
4683
XXH3_64bits_withSecretandSeed(const void* input, size_t len, const void* secret, size_t secretSize, XXH64_hash_t seed)
4684
{
4685
if (len <= XXH3_MIDSIZE_MAX)
4686
return XXH3_64bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), NULL);
4687
return XXH3_hashLong_64b_withSecret(input, len, seed, (const xxh_u8*)secret, secretSize);
4688
}
4689
4690
4691
/* === XXH3 streaming === */
4692
4693
/*
4694
* Malloc's a pointer that is always aligned to align.
4695
*
4696
* This must be freed with `XXH_alignedFree()`.
4697
*
4698
* malloc typically guarantees 16 byte alignment on 64-bit systems and 8 byte
4699
* alignment on 32-bit. This isn't enough for the 32 byte aligned loads in AVX2
4700
* or on 32-bit, the 16 byte aligned loads in SSE2 and NEON.
4701
*
4702
* This underalignment previously caused a rather obvious crash which went
4703
* completely unnoticed due to XXH3_createState() not actually being tested.
4704
* Credit to RedSpah for noticing this bug.
4705
*
4706
* The alignment is done manually: Functions like posix_memalign or _mm_malloc
4707
* are avoided: To maintain portability, we would have to write a fallback
4708
* like this anyways, and besides, testing for the existence of library
4709
* functions without relying on external build tools is impossible.
4710
*
4711
* The method is simple: Overallocate, manually align, and store the offset
4712
* to the original behind the returned pointer.
4713
*
4714
* Align must be a power of 2 and 8 <= align <= 128.
4715
*/
4716
static void* XXH_alignedMalloc(size_t s, size_t align)
4717
{
4718
XXH_ASSERT(align <= 128 && align >= 8); /* range check */
4719
XXH_ASSERT((align & (align-1)) == 0); /* power of 2 */
4720
XXH_ASSERT(s != 0 && s < (s + align)); /* empty/overflow */
4721
{ /* Overallocate to make room for manual realignment and an offset byte */
4722
xxh_u8* base = (xxh_u8*)XXH_malloc(s + align);
4723
if (base != NULL) {
4724
/*
4725
* Get the offset needed to align this pointer.
4726
*
4727
* Even if the returned pointer is aligned, there will always be
4728
* at least one byte to store the offset to the original pointer.
4729
*/
4730
size_t offset = align - ((size_t)base & (align - 1)); /* base % align */
4731
/* Add the offset for the now-aligned pointer */
4732
xxh_u8* ptr = base + offset;
4733
4734
XXH_ASSERT((size_t)ptr % align == 0);
4735
4736
/* Store the offset immediately before the returned pointer. */
4737
ptr[-1] = (xxh_u8)offset;
4738
return ptr;
4739
}
4740
return NULL;
4741
}
4742
}
4743
/*
4744
* Frees an aligned pointer allocated by XXH_alignedMalloc(). Don't pass
4745
* normal malloc'd pointers, XXH_alignedMalloc has a specific data layout.
4746
*/
4747
static void XXH_alignedFree(void* p)
4748
{
4749
if (p != NULL) {
4750
xxh_u8* ptr = (xxh_u8*)p;
4751
/* Get the offset byte we added in XXH_malloc. */
4752
xxh_u8 offset = ptr[-1];
4753
/* Free the original malloc'd pointer */
4754
xxh_u8* base = ptr - offset;
4755
XXH_free(base);
4756
}
4757
}
4758
/*! @ingroup xxh3_family */
4759
XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void)
4760
{
4761
XXH3_state_t* const state = (XXH3_state_t*)XXH_alignedMalloc(sizeof(XXH3_state_t), 64);
4762
if (state==NULL) return NULL;
4763
XXH3_INITSTATE(state);
4764
return state;
4765
}
4766
4767
/*! @ingroup xxh3_family */
4768
XXH_PUBLIC_API XXH_errorcode XXH3_freeState(XXH3_state_t* statePtr)
4769
{
4770
XXH_alignedFree(statePtr);
4771
return XXH_OK;
4772
}
4773
4774
/*! @ingroup xxh3_family */
4775
XXH_PUBLIC_API void
4776
XXH3_copyState(XXH3_state_t* dst_state, const XXH3_state_t* src_state)
4777
{
4778
XXH_memcpy(dst_state, src_state, sizeof(*dst_state));
4779
}
4780
4781
static void
4782
XXH3_reset_internal(XXH3_state_t* statePtr,
4783
XXH64_hash_t seed,
4784
const void* secret, size_t secretSize)
4785
{
4786
size_t const initStart = offsetof(XXH3_state_t, bufferedSize);
4787
size_t const initLength = offsetof(XXH3_state_t, nbStripesPerBlock) - initStart;
4788
XXH_ASSERT(offsetof(XXH3_state_t, nbStripesPerBlock) > initStart);
4789
XXH_ASSERT(statePtr != NULL);
4790
/* set members from bufferedSize to nbStripesPerBlock (excluded) to 0 */
4791
memset((char*)statePtr + initStart, 0, initLength);
4792
statePtr->acc[0] = XXH_PRIME32_3;
4793
statePtr->acc[1] = XXH_PRIME64_1;
4794
statePtr->acc[2] = XXH_PRIME64_2;
4795
statePtr->acc[3] = XXH_PRIME64_3;
4796
statePtr->acc[4] = XXH_PRIME64_4;
4797
statePtr->acc[5] = XXH_PRIME32_2;
4798
statePtr->acc[6] = XXH_PRIME64_5;
4799
statePtr->acc[7] = XXH_PRIME32_1;
4800
statePtr->seed = seed;
4801
statePtr->useSeed = (seed != 0);
4802
statePtr->extSecret = (const unsigned char*)secret;
4803
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
4804
statePtr->secretLimit = secretSize - XXH_STRIPE_LEN;
4805
statePtr->nbStripesPerBlock = statePtr->secretLimit / XXH_SECRET_CONSUME_RATE;
4806
}
4807
4808
/*! @ingroup xxh3_family */
4809
XXH_PUBLIC_API XXH_errorcode
4810
XXH3_64bits_reset(XXH3_state_t* statePtr)
4811
{
4812
if (statePtr == NULL) return XXH_ERROR;
4813
XXH3_reset_internal(statePtr, 0, XXH3_kSecret, XXH_SECRET_DEFAULT_SIZE);
4814
return XXH_OK;
4815
}
4816
4817
/*! @ingroup xxh3_family */
4818
XXH_PUBLIC_API XXH_errorcode
4819
XXH3_64bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize)
4820
{
4821
if (statePtr == NULL) return XXH_ERROR;
4822
XXH3_reset_internal(statePtr, 0, secret, secretSize);
4823
if (secret == NULL) return XXH_ERROR;
4824
if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
4825
return XXH_OK;
4826
}
4827
4828
/*! @ingroup xxh3_family */
4829
XXH_PUBLIC_API XXH_errorcode
4830
XXH3_64bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed)
4831
{
4832
if (statePtr == NULL) return XXH_ERROR;
4833
if (seed==0) return XXH3_64bits_reset(statePtr);
4834
if ((seed != statePtr->seed) || (statePtr->extSecret != NULL))
4835
XXH3_initCustomSecret(statePtr->customSecret, seed);
4836
XXH3_reset_internal(statePtr, seed, NULL, XXH_SECRET_DEFAULT_SIZE);
4837
return XXH_OK;
4838
}
4839
4840
/*! @ingroup xxh3_family */
4841
XXH_PUBLIC_API XXH_errorcode
4842
XXH3_64bits_reset_withSecretandSeed(XXH3_state_t* statePtr, const void* secret, size_t secretSize, XXH64_hash_t seed64)
4843
{
4844
if (statePtr == NULL) return XXH_ERROR;
4845
if (secret == NULL) return XXH_ERROR;
4846
if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
4847
XXH3_reset_internal(statePtr, seed64, secret, secretSize);
4848
statePtr->useSeed = 1; /* always, even if seed64==0 */
4849
return XXH_OK;
4850
}
4851
4852
/* Note : when XXH3_consumeStripes() is invoked,
4853
* there must be a guarantee that at least one more byte must be consumed from input
4854
* so that the function can blindly consume all stripes using the "normal" secret segment */
4855
XXH_FORCE_INLINE void
4856
XXH3_consumeStripes(xxh_u64* XXH_RESTRICT acc,
4857
size_t* XXH_RESTRICT nbStripesSoFarPtr, size_t nbStripesPerBlock,
4858
const xxh_u8* XXH_RESTRICT input, size_t nbStripes,
4859
const xxh_u8* XXH_RESTRICT secret, size_t secretLimit,
4860
XXH3_f_accumulate_512 f_acc512,
4861
XXH3_f_scrambleAcc f_scramble)
4862
{
4863
XXH_ASSERT(nbStripes <= nbStripesPerBlock); /* can handle max 1 scramble per invocation */
4864
XXH_ASSERT(*nbStripesSoFarPtr < nbStripesPerBlock);
4865
if (nbStripesPerBlock - *nbStripesSoFarPtr <= nbStripes) {
4866
/* need a scrambling operation */
4867
size_t const nbStripesToEndofBlock = nbStripesPerBlock - *nbStripesSoFarPtr;
4868
size_t const nbStripesAfterBlock = nbStripes - nbStripesToEndofBlock;
4869
XXH3_accumulate(acc, input, secret + nbStripesSoFarPtr[0] * XXH_SECRET_CONSUME_RATE, nbStripesToEndofBlock, f_acc512);
4870
f_scramble(acc, secret + secretLimit);
4871
XXH3_accumulate(acc, input + nbStripesToEndofBlock * XXH_STRIPE_LEN, secret, nbStripesAfterBlock, f_acc512);
4872
*nbStripesSoFarPtr = nbStripesAfterBlock;
4873
} else {
4874
XXH3_accumulate(acc, input, secret + nbStripesSoFarPtr[0] * XXH_SECRET_CONSUME_RATE, nbStripes, f_acc512);
4875
*nbStripesSoFarPtr += nbStripes;
4876
}
4877
}
4878
4879
#ifndef XXH3_STREAM_USE_STACK
4880
# ifndef __clang__ /* clang doesn't need additional stack space */
4881
# define XXH3_STREAM_USE_STACK 1
4882
# endif
4883
#endif
4884
/*
4885
* Both XXH3_64bits_update and XXH3_128bits_update use this routine.
4886
*/
4887
XXH_FORCE_INLINE XXH_errorcode
4888
XXH3_update(XXH3_state_t* XXH_RESTRICT const state,
4889
const xxh_u8* XXH_RESTRICT input, size_t len,
4890
XXH3_f_accumulate_512 f_acc512,
4891
XXH3_f_scrambleAcc f_scramble)
4892
{
4893
if (input==NULL) {
4894
XXH_ASSERT(len == 0);
4895
return XXH_OK;
4896
}
4897
4898
XXH_ASSERT(state != NULL);
4899
{ const xxh_u8* const bEnd = input + len;
4900
const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
4901
#if defined(XXH3_STREAM_USE_STACK) && XXH3_STREAM_USE_STACK >= 1
4902
/* For some reason, gcc and MSVC seem to suffer greatly
4903
* when operating accumulators directly into state.
4904
* Operating into stack space seems to enable proper optimization.
4905
* clang, on the other hand, doesn't seem to need this trick */
4906
XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[8]; memcpy(acc, state->acc, sizeof(acc));
4907
#else
4908
xxh_u64* XXH_RESTRICT const acc = state->acc;
4909
#endif
4910
state->totalLen += len;
4911
XXH_ASSERT(state->bufferedSize <= XXH3_INTERNALBUFFER_SIZE);
4912
4913
/* small input : just fill in tmp buffer */
4914
if (state->bufferedSize + len <= XXH3_INTERNALBUFFER_SIZE) {
4915
XXH_memcpy(state->buffer + state->bufferedSize, input, len);
4916
state->bufferedSize += (XXH32_hash_t)len;
4917
return XXH_OK;
4918
}
4919
4920
/* total input is now > XXH3_INTERNALBUFFER_SIZE */
4921
#define XXH3_INTERNALBUFFER_STRIPES (XXH3_INTERNALBUFFER_SIZE / XXH_STRIPE_LEN)
4922
XXH_STATIC_ASSERT(XXH3_INTERNALBUFFER_SIZE % XXH_STRIPE_LEN == 0); /* clean multiple */
4923
4924
/*
4925
* Internal buffer is partially filled (always, except at beginning)
4926
* Complete it, then consume it.
4927
*/
4928
if (state->bufferedSize) {
4929
size_t const loadSize = XXH3_INTERNALBUFFER_SIZE - state->bufferedSize;
4930
XXH_memcpy(state->buffer + state->bufferedSize, input, loadSize);
4931
input += loadSize;
4932
XXH3_consumeStripes(acc,
4933
&state->nbStripesSoFar, state->nbStripesPerBlock,
4934
state->buffer, XXH3_INTERNALBUFFER_STRIPES,
4935
secret, state->secretLimit,
4936
f_acc512, f_scramble);
4937
state->bufferedSize = 0;
4938
}
4939
XXH_ASSERT(input < bEnd);
4940
4941
/* large input to consume : ingest per full block */
4942
if ((size_t)(bEnd - input) > state->nbStripesPerBlock * XXH_STRIPE_LEN) {
4943
size_t nbStripes = (size_t)(bEnd - 1 - input) / XXH_STRIPE_LEN;
4944
XXH_ASSERT(state->nbStripesPerBlock >= state->nbStripesSoFar);
4945
/* join to current block's end */
4946
{ size_t const nbStripesToEnd = state->nbStripesPerBlock - state->nbStripesSoFar;
4947
XXH_ASSERT(nbStripesToEnd <= nbStripes);
4948
XXH3_accumulate(acc, input, secret + state->nbStripesSoFar * XXH_SECRET_CONSUME_RATE, nbStripesToEnd, f_acc512);
4949
f_scramble(acc, secret + state->secretLimit);
4950
state->nbStripesSoFar = 0;
4951
input += nbStripesToEnd * XXH_STRIPE_LEN;
4952
nbStripes -= nbStripesToEnd;
4953
}
4954
/* consume per entire blocks */
4955
while(nbStripes >= state->nbStripesPerBlock) {
4956
XXH3_accumulate(acc, input, secret, state->nbStripesPerBlock, f_acc512);
4957
f_scramble(acc, secret + state->secretLimit);
4958
input += state->nbStripesPerBlock * XXH_STRIPE_LEN;
4959
nbStripes -= state->nbStripesPerBlock;
4960
}
4961
/* consume last partial block */
4962
XXH3_accumulate(acc, input, secret, nbStripes, f_acc512);
4963
input += nbStripes * XXH_STRIPE_LEN;
4964
XXH_ASSERT(input < bEnd); /* at least some bytes left */
4965
state->nbStripesSoFar = nbStripes;
4966
/* buffer predecessor of last partial stripe */
4967
XXH_memcpy(state->buffer + sizeof(state->buffer) - XXH_STRIPE_LEN, input - XXH_STRIPE_LEN, XXH_STRIPE_LEN);
4968
XXH_ASSERT(bEnd - input <= XXH_STRIPE_LEN);
4969
} else {
4970
/* content to consume <= block size */
4971
/* Consume input by a multiple of internal buffer size */
4972
if (bEnd - input > XXH3_INTERNALBUFFER_SIZE) {
4973
const xxh_u8* const limit = bEnd - XXH3_INTERNALBUFFER_SIZE;
4974
do {
4975
XXH3_consumeStripes(acc,
4976
&state->nbStripesSoFar, state->nbStripesPerBlock,
4977
input, XXH3_INTERNALBUFFER_STRIPES,
4978
secret, state->secretLimit,
4979
f_acc512, f_scramble);
4980
input += XXH3_INTERNALBUFFER_SIZE;
4981
} while (input<limit);
4982
/* buffer predecessor of last partial stripe */
4983
XXH_memcpy(state->buffer + sizeof(state->buffer) - XXH_STRIPE_LEN, input - XXH_STRIPE_LEN, XXH_STRIPE_LEN);
4984
}
4985
}
4986
4987
/* Some remaining input (always) : buffer it */
4988
XXH_ASSERT(input < bEnd);
4989
XXH_ASSERT(bEnd - input <= XXH3_INTERNALBUFFER_SIZE);
4990
XXH_ASSERT(state->bufferedSize == 0);
4991
XXH_memcpy(state->buffer, input, (size_t)(bEnd-input));
4992
state->bufferedSize = (XXH32_hash_t)(bEnd-input);
4993
#if defined(XXH3_STREAM_USE_STACK) && XXH3_STREAM_USE_STACK >= 1
4994
/* save stack accumulators into state */
4995
memcpy(state->acc, acc, sizeof(acc));
4996
#endif
4997
}
4998
4999
return XXH_OK;
5000
}
5001
5002
/*! @ingroup xxh3_family */
5003
XXH_PUBLIC_API XXH_errorcode
5004
XXH3_64bits_update(XXH3_state_t* state, const void* input, size_t len)
5005
{
5006
return XXH3_update(state, (const xxh_u8*)input, len,
5007
XXH3_accumulate_512, XXH3_scrambleAcc);
5008
}
5009
5010
5011
XXH_FORCE_INLINE void
5012
XXH3_digest_long (XXH64_hash_t* acc,
5013
const XXH3_state_t* state,
5014
const unsigned char* secret)
5015
{
5016
/*
5017
* Digest on a local copy. This way, the state remains unaltered, and it can
5018
* continue ingesting more input afterwards.
5019
*/
5020
XXH_memcpy(acc, state->acc, sizeof(state->acc));
5021
if (state->bufferedSize >= XXH_STRIPE_LEN) {
5022
size_t const nbStripes = (state->bufferedSize - 1) / XXH_STRIPE_LEN;
5023
size_t nbStripesSoFar = state->nbStripesSoFar;
5024
XXH3_consumeStripes(acc,
5025
&nbStripesSoFar, state->nbStripesPerBlock,
5026
state->buffer, nbStripes,
5027
secret, state->secretLimit,
5028
XXH3_accumulate_512, XXH3_scrambleAcc);
5029
/* last stripe */
5030
XXH3_accumulate_512(acc,
5031
state->buffer + state->bufferedSize - XXH_STRIPE_LEN,
5032
secret + state->secretLimit - XXH_SECRET_LASTACC_START);
5033
} else { /* bufferedSize < XXH_STRIPE_LEN */
5034
xxh_u8 lastStripe[XXH_STRIPE_LEN];
5035
size_t const catchupSize = XXH_STRIPE_LEN - state->bufferedSize;
5036
XXH_ASSERT(state->bufferedSize > 0); /* there is always some input buffered */
5037
XXH_memcpy(lastStripe, state->buffer + sizeof(state->buffer) - catchupSize, catchupSize);
5038
XXH_memcpy(lastStripe + catchupSize, state->buffer, state->bufferedSize);
5039
XXH3_accumulate_512(acc,
5040
lastStripe,
5041
secret + state->secretLimit - XXH_SECRET_LASTACC_START);
5042
}
5043
}
5044
5045
/*! @ingroup xxh3_family */
5046
XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_digest (const XXH3_state_t* state)
5047
{
5048
const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
5049
if (state->totalLen > XXH3_MIDSIZE_MAX) {
5050
XXH_ALIGN(XXH_ACC_ALIGN) XXH64_hash_t acc[XXH_ACC_NB];
5051
XXH3_digest_long(acc, state, secret);
5052
return XXH3_mergeAccs(acc,
5053
secret + XXH_SECRET_MERGEACCS_START,
5054
(xxh_u64)state->totalLen * XXH_PRIME64_1);
5055
}
5056
/* totalLen <= XXH3_MIDSIZE_MAX: digesting a short input */
5057
if (state->useSeed)
5058
return XXH3_64bits_withSeed(state->buffer, (size_t)state->totalLen, state->seed);
5059
return XXH3_64bits_withSecret(state->buffer, (size_t)(state->totalLen),
5060
secret, state->secretLimit + XXH_STRIPE_LEN);
5061
}
5062
5063
5064
5065
/* ==========================================
5066
* XXH3 128 bits (a.k.a XXH128)
5067
* ==========================================
5068
* XXH3's 128-bit variant has better mixing and strength than the 64-bit variant,
5069
* even without counting the significantly larger output size.
5070
*
5071
* For example, extra steps are taken to avoid the seed-dependent collisions
5072
* in 17-240 byte inputs (See XXH3_mix16B and XXH128_mix32B).
5073
*
5074
* This strength naturally comes at the cost of some speed, especially on short
5075
* lengths. Note that longer hashes are about as fast as the 64-bit version
5076
* due to it using only a slight modification of the 64-bit loop.
5077
*
5078
* XXH128 is also more oriented towards 64-bit machines. It is still extremely
5079
* fast for a _128-bit_ hash on 32-bit (it usually clears XXH64).
5080
*/
5081
5082
XXH_FORCE_INLINE XXH128_hash_t
5083
XXH3_len_1to3_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5084
{
5085
/* A doubled version of 1to3_64b with different constants. */
5086
XXH_ASSERT(input != NULL);
5087
XXH_ASSERT(1 <= len && len <= 3);
5088
XXH_ASSERT(secret != NULL);
5089
/*
5090
* len = 1: combinedl = { input[0], 0x01, input[0], input[0] }
5091
* len = 2: combinedl = { input[1], 0x02, input[0], input[1] }
5092
* len = 3: combinedl = { input[2], 0x03, input[0], input[1] }
5093
*/
5094
{ xxh_u8 const c1 = input[0];
5095
xxh_u8 const c2 = input[len >> 1];
5096
xxh_u8 const c3 = input[len - 1];
5097
xxh_u32 const combinedl = ((xxh_u32)c1 <<16) | ((xxh_u32)c2 << 24)
5098
| ((xxh_u32)c3 << 0) | ((xxh_u32)len << 8);
5099
xxh_u32 const combinedh = XXH_rotl32(XXH_swap32(combinedl), 13);
5100
xxh_u64 const bitflipl = (XXH_readLE32(secret) ^ XXH_readLE32(secret+4)) + seed;
5101
xxh_u64 const bitfliph = (XXH_readLE32(secret+8) ^ XXH_readLE32(secret+12)) - seed;
5102
xxh_u64 const keyed_lo = (xxh_u64)combinedl ^ bitflipl;
5103
xxh_u64 const keyed_hi = (xxh_u64)combinedh ^ bitfliph;
5104
XXH128_hash_t h128;
5105
h128.low64 = XXH64_avalanche(keyed_lo);
5106
h128.high64 = XXH64_avalanche(keyed_hi);
5107
return h128;
5108
}
5109
}
5110
5111
XXH_FORCE_INLINE XXH128_hash_t
5112
XXH3_len_4to8_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5113
{
5114
XXH_ASSERT(input != NULL);
5115
XXH_ASSERT(secret != NULL);
5116
XXH_ASSERT(4 <= len && len <= 8);
5117
seed ^= (xxh_u64)XXH_swap32((xxh_u32)seed) << 32;
5118
{ xxh_u32 const input_lo = XXH_readLE32(input);
5119
xxh_u32 const input_hi = XXH_readLE32(input + len - 4);
5120
xxh_u64 const input_64 = input_lo + ((xxh_u64)input_hi << 32);
5121
xxh_u64 const bitflip = (XXH_readLE64(secret+16) ^ XXH_readLE64(secret+24)) + seed;
5122
xxh_u64 const keyed = input_64 ^ bitflip;
5123
5124
/* Shift len to the left to ensure it is even, this avoids even multiplies. */
5125
XXH128_hash_t m128 = XXH_mult64to128(keyed, XXH_PRIME64_1 + (len << 2));
5126
5127
m128.high64 += (m128.low64 << 1);
5128
m128.low64 ^= (m128.high64 >> 3);
5129
5130
m128.low64 = XXH_xorshift64(m128.low64, 35);
5131
m128.low64 *= 0x9FB21C651E98DF25ULL;
5132
m128.low64 = XXH_xorshift64(m128.low64, 28);
5133
m128.high64 = XXH3_avalanche(m128.high64);
5134
return m128;
5135
}
5136
}
5137
5138
XXH_FORCE_INLINE XXH128_hash_t
5139
XXH3_len_9to16_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5140
{
5141
XXH_ASSERT(input != NULL);
5142
XXH_ASSERT(secret != NULL);
5143
XXH_ASSERT(9 <= len && len <= 16);
5144
{ xxh_u64 const bitflipl = (XXH_readLE64(secret+32) ^ XXH_readLE64(secret+40)) - seed;
5145
xxh_u64 const bitfliph = (XXH_readLE64(secret+48) ^ XXH_readLE64(secret+56)) + seed;
5146
xxh_u64 const input_lo = XXH_readLE64(input);
5147
xxh_u64 input_hi = XXH_readLE64(input + len - 8);
5148
XXH128_hash_t m128 = XXH_mult64to128(input_lo ^ input_hi ^ bitflipl, XXH_PRIME64_1);
5149
/*
5150
* Put len in the middle of m128 to ensure that the length gets mixed to
5151
* both the low and high bits in the 128x64 multiply below.
5152
*/
5153
m128.low64 += (xxh_u64)(len - 1) << 54;
5154
input_hi ^= bitfliph;
5155
/*
5156
* Add the high 32 bits of input_hi to the high 32 bits of m128, then
5157
* add the long product of the low 32 bits of input_hi and XXH_PRIME32_2 to
5158
* the high 64 bits of m128.
5159
*
5160
* The best approach to this operation is different on 32-bit and 64-bit.
5161
*/
5162
if (sizeof(void *) < sizeof(xxh_u64)) { /* 32-bit */
5163
/*
5164
* 32-bit optimized version, which is more readable.
5165
*
5166
* On 32-bit, it removes an ADC and delays a dependency between the two
5167
* halves of m128.high64, but it generates an extra mask on 64-bit.
5168
*/
5169
m128.high64 += (input_hi & 0xFFFFFFFF00000000ULL) + XXH_mult32to64((xxh_u32)input_hi, XXH_PRIME32_2);
5170
} else {
5171
/*
5172
* 64-bit optimized (albeit more confusing) version.
5173
*
5174
* Uses some properties of addition and multiplication to remove the mask:
5175
*
5176
* Let:
5177
* a = input_hi.lo = (input_hi & 0x00000000FFFFFFFF)
5178
* b = input_hi.hi = (input_hi & 0xFFFFFFFF00000000)
5179
* c = XXH_PRIME32_2
5180
*
5181
* a + (b * c)
5182
* Inverse Property: x + y - x == y
5183
* a + (b * (1 + c - 1))
5184
* Distributive Property: x * (y + z) == (x * y) + (x * z)
5185
* a + (b * 1) + (b * (c - 1))
5186
* Identity Property: x * 1 == x
5187
* a + b + (b * (c - 1))
5188
*
5189
* Substitute a, b, and c:
5190
* input_hi.hi + input_hi.lo + ((xxh_u64)input_hi.lo * (XXH_PRIME32_2 - 1))
5191
*
5192
* Since input_hi.hi + input_hi.lo == input_hi, we get this:
5193
* input_hi + ((xxh_u64)input_hi.lo * (XXH_PRIME32_2 - 1))
5194
*/
5195
m128.high64 += input_hi + XXH_mult32to64((xxh_u32)input_hi, XXH_PRIME32_2 - 1);
5196
}
5197
/* m128 ^= XXH_swap64(m128 >> 64); */
5198
m128.low64 ^= XXH_swap64(m128.high64);
5199
5200
{ /* 128x64 multiply: h128 = m128 * XXH_PRIME64_2; */
5201
XXH128_hash_t h128 = XXH_mult64to128(m128.low64, XXH_PRIME64_2);
5202
h128.high64 += m128.high64 * XXH_PRIME64_2;
5203
5204
h128.low64 = XXH3_avalanche(h128.low64);
5205
h128.high64 = XXH3_avalanche(h128.high64);
5206
return h128;
5207
} }
5208
}
5209
5210
/*
5211
* Assumption: `secret` size is >= XXH3_SECRET_SIZE_MIN
5212
*/
5213
XXH_FORCE_INLINE XXH128_hash_t
5214
XXH3_len_0to16_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5215
{
5216
XXH_ASSERT(len <= 16);
5217
{ if (len > 8) return XXH3_len_9to16_128b(input, len, secret, seed);
5218
if (len >= 4) return XXH3_len_4to8_128b(input, len, secret, seed);
5219
if (len) return XXH3_len_1to3_128b(input, len, secret, seed);
5220
{ XXH128_hash_t h128;
5221
xxh_u64 const bitflipl = XXH_readLE64(secret+64) ^ XXH_readLE64(secret+72);
5222
xxh_u64 const bitfliph = XXH_readLE64(secret+80) ^ XXH_readLE64(secret+88);
5223
h128.low64 = XXH64_avalanche(seed ^ bitflipl);
5224
h128.high64 = XXH64_avalanche( seed ^ bitfliph);
5225
return h128;
5226
} }
5227
}
5228
5229
/*
5230
* A bit slower than XXH3_mix16B, but handles multiply by zero better.
5231
*/
5232
XXH_FORCE_INLINE XXH128_hash_t
5233
XXH128_mix32B(XXH128_hash_t acc, const xxh_u8* input_1, const xxh_u8* input_2,
5234
const xxh_u8* secret, XXH64_hash_t seed)
5235
{
5236
acc.low64 += XXH3_mix16B (input_1, secret+0, seed);
5237
acc.low64 ^= XXH_readLE64(input_2) + XXH_readLE64(input_2 + 8);
5238
acc.high64 += XXH3_mix16B (input_2, secret+16, seed);
5239
acc.high64 ^= XXH_readLE64(input_1) + XXH_readLE64(input_1 + 8);
5240
return acc;
5241
}
5242
5243
5244
XXH_FORCE_INLINE XXH128_hash_t
5245
XXH3_len_17to128_128b(const xxh_u8* XXH_RESTRICT input, size_t len,
5246
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5247
XXH64_hash_t seed)
5248
{
5249
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
5250
XXH_ASSERT(16 < len && len <= 128);
5251
5252
{ XXH128_hash_t acc;
5253
acc.low64 = len * XXH_PRIME64_1;
5254
acc.high64 = 0;
5255
if (len > 32) {
5256
if (len > 64) {
5257
if (len > 96) {
5258
acc = XXH128_mix32B(acc, input+48, input+len-64, secret+96, seed);
5259
}
5260
acc = XXH128_mix32B(acc, input+32, input+len-48, secret+64, seed);
5261
}
5262
acc = XXH128_mix32B(acc, input+16, input+len-32, secret+32, seed);
5263
}
5264
acc = XXH128_mix32B(acc, input, input+len-16, secret, seed);
5265
{ XXH128_hash_t h128;
5266
h128.low64 = acc.low64 + acc.high64;
5267
h128.high64 = (acc.low64 * XXH_PRIME64_1)
5268
+ (acc.high64 * XXH_PRIME64_4)
5269
+ ((len - seed) * XXH_PRIME64_2);
5270
h128.low64 = XXH3_avalanche(h128.low64);
5271
h128.high64 = (XXH64_hash_t)0 - XXH3_avalanche(h128.high64);
5272
return h128;
5273
}
5274
}
5275
}
5276
5277
XXH_NO_INLINE XXH128_hash_t
5278
XXH3_len_129to240_128b(const xxh_u8* XXH_RESTRICT input, size_t len,
5279
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5280
XXH64_hash_t seed)
5281
{
5282
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
5283
XXH_ASSERT(128 < len && len <= XXH3_MIDSIZE_MAX);
5284
5285
{ XXH128_hash_t acc;
5286
int const nbRounds = (int)len / 32;
5287
int i;
5288
acc.low64 = len * XXH_PRIME64_1;
5289
acc.high64 = 0;
5290
for (i=0; i<4; i++) {
5291
acc = XXH128_mix32B(acc,
5292
input + (32 * i),
5293
input + (32 * i) + 16,
5294
secret + (32 * i),
5295
seed);
5296
}
5297
acc.low64 = XXH3_avalanche(acc.low64);
5298
acc.high64 = XXH3_avalanche(acc.high64);
5299
XXH_ASSERT(nbRounds >= 4);
5300
for (i=4 ; i < nbRounds; i++) {
5301
acc = XXH128_mix32B(acc,
5302
input + (32 * i),
5303
input + (32 * i) + 16,
5304
secret + XXH3_MIDSIZE_STARTOFFSET + (32 * (i - 4)),
5305
seed);
5306
}
5307
/* last bytes */
5308
acc = XXH128_mix32B(acc,
5309
input + len - 16,
5310
input + len - 32,
5311
secret + XXH3_SECRET_SIZE_MIN - XXH3_MIDSIZE_LASTOFFSET - 16,
5312
0ULL - seed);
5313
5314
{ XXH128_hash_t h128;
5315
h128.low64 = acc.low64 + acc.high64;
5316
h128.high64 = (acc.low64 * XXH_PRIME64_1)
5317
+ (acc.high64 * XXH_PRIME64_4)
5318
+ ((len - seed) * XXH_PRIME64_2);
5319
h128.low64 = XXH3_avalanche(h128.low64);
5320
h128.high64 = (XXH64_hash_t)0 - XXH3_avalanche(h128.high64);
5321
return h128;
5322
}
5323
}
5324
}
5325
5326
XXH_FORCE_INLINE XXH128_hash_t
5327
XXH3_hashLong_128b_internal(const void* XXH_RESTRICT input, size_t len,
5328
const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5329
XXH3_f_accumulate_512 f_acc512,
5330
XXH3_f_scrambleAcc f_scramble)
5331
{
5332
XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[XXH_ACC_NB] = XXH3_INIT_ACC;
5333
5334
XXH3_hashLong_internal_loop(acc, (const xxh_u8*)input, len, secret, secretSize, f_acc512, f_scramble);
5335
5336
/* converge into final hash */
5337
XXH_STATIC_ASSERT(sizeof(acc) == 64);
5338
XXH_ASSERT(secretSize >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
5339
{ XXH128_hash_t h128;
5340
h128.low64 = XXH3_mergeAccs(acc,
5341
secret + XXH_SECRET_MERGEACCS_START,
5342
(xxh_u64)len * XXH_PRIME64_1);
5343
h128.high64 = XXH3_mergeAccs(acc,
5344
secret + secretSize
5345
- sizeof(acc) - XXH_SECRET_MERGEACCS_START,
5346
~((xxh_u64)len * XXH_PRIME64_2));
5347
return h128;
5348
}
5349
}
5350
5351
/*
5352
* It's important for performance that XXH3_hashLong is not inlined.
5353
*/
5354
XXH_NO_INLINE XXH128_hash_t
5355
XXH3_hashLong_128b_default(const void* XXH_RESTRICT input, size_t len,
5356
XXH64_hash_t seed64,
5357
const void* XXH_RESTRICT secret, size_t secretLen)
5358
{
5359
(void)seed64; (void)secret; (void)secretLen;
5360
return XXH3_hashLong_128b_internal(input, len, XXH3_kSecret, sizeof(XXH3_kSecret),
5361
XXH3_accumulate_512, XXH3_scrambleAcc);
5362
}
5363
5364
/*
5365
* It's important for performance to pass @secretLen (when it's static)
5366
* to the compiler, so that it can properly optimize the vectorized loop.
5367
*/
5368
XXH_FORCE_INLINE XXH128_hash_t
5369
XXH3_hashLong_128b_withSecret(const void* XXH_RESTRICT input, size_t len,
5370
XXH64_hash_t seed64,
5371
const void* XXH_RESTRICT secret, size_t secretLen)
5372
{
5373
(void)seed64;
5374
return XXH3_hashLong_128b_internal(input, len, (const xxh_u8*)secret, secretLen,
5375
XXH3_accumulate_512, XXH3_scrambleAcc);
5376
}
5377
5378
XXH_FORCE_INLINE XXH128_hash_t
5379
XXH3_hashLong_128b_withSeed_internal(const void* XXH_RESTRICT input, size_t len,
5380
XXH64_hash_t seed64,
5381
XXH3_f_accumulate_512 f_acc512,
5382
XXH3_f_scrambleAcc f_scramble,
5383
XXH3_f_initCustomSecret f_initSec)
5384
{
5385
if (seed64 == 0)
5386
return XXH3_hashLong_128b_internal(input, len,
5387
XXH3_kSecret, sizeof(XXH3_kSecret),
5388
f_acc512, f_scramble);
5389
{ XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
5390
f_initSec(secret, seed64);
5391
return XXH3_hashLong_128b_internal(input, len, (const xxh_u8*)secret, sizeof(secret),
5392
f_acc512, f_scramble);
5393
}
5394
}
5395
5396
/*
5397
* It's important for performance that XXH3_hashLong is not inlined.
5398
*/
5399
XXH_NO_INLINE XXH128_hash_t
5400
XXH3_hashLong_128b_withSeed(const void* input, size_t len,
5401
XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen)
5402
{
5403
(void)secret; (void)secretLen;
5404
return XXH3_hashLong_128b_withSeed_internal(input, len, seed64,
5405
XXH3_accumulate_512, XXH3_scrambleAcc, XXH3_initCustomSecret);
5406
}
5407
5408
typedef XXH128_hash_t (*XXH3_hashLong128_f)(const void* XXH_RESTRICT, size_t,
5409
XXH64_hash_t, const void* XXH_RESTRICT, size_t);
5410
5411
XXH_FORCE_INLINE XXH128_hash_t
5412
XXH3_128bits_internal(const void* input, size_t len,
5413
XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen,
5414
XXH3_hashLong128_f f_hl128)
5415
{
5416
XXH_ASSERT(secretLen >= XXH3_SECRET_SIZE_MIN);
5417
/*
5418
* If an action is to be taken if `secret` conditions are not respected,
5419
* it should be done here.
5420
* For now, it's a contract pre-condition.
5421
* Adding a check and a branch here would cost performance at every hash.
5422
*/
5423
if (len <= 16)
5424
return XXH3_len_0to16_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, seed64);
5425
if (len <= 128)
5426
return XXH3_len_17to128_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
5427
if (len <= XXH3_MIDSIZE_MAX)
5428
return XXH3_len_129to240_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
5429
return f_hl128(input, len, seed64, secret, secretLen);
5430
}
5431
5432
5433
/* === Public XXH128 API === */
5434
5435
/*! @ingroup xxh3_family */
5436
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits(const void* input, size_t len)
5437
{
5438
return XXH3_128bits_internal(input, len, 0,
5439
XXH3_kSecret, sizeof(XXH3_kSecret),
5440
XXH3_hashLong_128b_default);
5441
}
5442
5443
/*! @ingroup xxh3_family */
5444
XXH_PUBLIC_API XXH128_hash_t
5445
XXH3_128bits_withSecret(const void* input, size_t len, const void* secret, size_t secretSize)
5446
{
5447
return XXH3_128bits_internal(input, len, 0,
5448
(const xxh_u8*)secret, secretSize,
5449
XXH3_hashLong_128b_withSecret);
5450
}
5451
5452
/*! @ingroup xxh3_family */
5453
XXH_PUBLIC_API XXH128_hash_t
5454
XXH3_128bits_withSeed(const void* input, size_t len, XXH64_hash_t seed)
5455
{
5456
return XXH3_128bits_internal(input, len, seed,
5457
XXH3_kSecret, sizeof(XXH3_kSecret),
5458
XXH3_hashLong_128b_withSeed);
5459
}
5460
5461
/*! @ingroup xxh3_family */
5462
XXH_PUBLIC_API XXH128_hash_t
5463
XXH3_128bits_withSecretandSeed(const void* input, size_t len, const void* secret, size_t secretSize, XXH64_hash_t seed)
5464
{
5465
if (len <= XXH3_MIDSIZE_MAX)
5466
return XXH3_128bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), NULL);
5467
return XXH3_hashLong_128b_withSecret(input, len, seed, secret, secretSize);
5468
}
5469
5470
/*! @ingroup xxh3_family */
5471
XXH_PUBLIC_API XXH128_hash_t
5472
XXH128(const void* input, size_t len, XXH64_hash_t seed)
5473
{
5474
return XXH3_128bits_withSeed(input, len, seed);
5475
}
5476
5477
5478
/* === XXH3 128-bit streaming === */
5479
5480
/*
5481
* All initialization and update functions are identical to 64-bit streaming variant.
5482
* The only difference is the finalization routine.
5483
*/
5484
5485
/*! @ingroup xxh3_family */
5486
XXH_PUBLIC_API XXH_errorcode
5487
XXH3_128bits_reset(XXH3_state_t* statePtr)
5488
{
5489
return XXH3_64bits_reset(statePtr);
5490
}
5491
5492
/*! @ingroup xxh3_family */
5493
XXH_PUBLIC_API XXH_errorcode
5494
XXH3_128bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize)
5495
{
5496
return XXH3_64bits_reset_withSecret(statePtr, secret, secretSize);
5497
}
5498
5499
/*! @ingroup xxh3_family */
5500
XXH_PUBLIC_API XXH_errorcode
5501
XXH3_128bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed)
5502
{
5503
return XXH3_64bits_reset_withSeed(statePtr, seed);
5504
}
5505
5506
/*! @ingroup xxh3_family */
5507
XXH_PUBLIC_API XXH_errorcode
5508
XXH3_128bits_reset_withSecretandSeed(XXH3_state_t* statePtr, const void* secret, size_t secretSize, XXH64_hash_t seed)
5509
{
5510
return XXH3_64bits_reset_withSecretandSeed(statePtr, secret, secretSize, seed);
5511
}
5512
5513
/*! @ingroup xxh3_family */
5514
XXH_PUBLIC_API XXH_errorcode
5515
XXH3_128bits_update(XXH3_state_t* state, const void* input, size_t len)
5516
{
5517
return XXH3_update(state, (const xxh_u8*)input, len,
5518
XXH3_accumulate_512, XXH3_scrambleAcc);
5519
}
5520
5521
/*! @ingroup xxh3_family */
5522
XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_digest (const XXH3_state_t* state)
5523
{
5524
const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
5525
if (state->totalLen > XXH3_MIDSIZE_MAX) {
5526
XXH_ALIGN(XXH_ACC_ALIGN) XXH64_hash_t acc[XXH_ACC_NB];
5527
XXH3_digest_long(acc, state, secret);
5528
XXH_ASSERT(state->secretLimit + XXH_STRIPE_LEN >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
5529
{ XXH128_hash_t h128;
5530
h128.low64 = XXH3_mergeAccs(acc,
5531
secret + XXH_SECRET_MERGEACCS_START,
5532
(xxh_u64)state->totalLen * XXH_PRIME64_1);
5533
h128.high64 = XXH3_mergeAccs(acc,
5534
secret + state->secretLimit + XXH_STRIPE_LEN
5535
- sizeof(acc) - XXH_SECRET_MERGEACCS_START,
5536
~((xxh_u64)state->totalLen * XXH_PRIME64_2));
5537
return h128;
5538
}
5539
}
5540
/* len <= XXH3_MIDSIZE_MAX : short code */
5541
if (state->seed)
5542
return XXH3_128bits_withSeed(state->buffer, (size_t)state->totalLen, state->seed);
5543
return XXH3_128bits_withSecret(state->buffer, (size_t)(state->totalLen),
5544
secret, state->secretLimit + XXH_STRIPE_LEN);
5545
}
5546
5547
/* 128-bit utility functions */
5548
5549
#include <string.h> /* memcmp, memcpy */
5550
5551
/* return : 1 is equal, 0 if different */
5552
/*! @ingroup xxh3_family */
5553
XXH_PUBLIC_API int XXH128_isEqual(XXH128_hash_t h1, XXH128_hash_t h2)
5554
{
5555
/* note : XXH128_hash_t is compact, it has no padding byte */
5556
return !(memcmp(&h1, &h2, sizeof(h1)));
5557
}
5558
5559
/* This prototype is compatible with stdlib's qsort().
5560
* return : >0 if *h128_1 > *h128_2
5561
* <0 if *h128_1 < *h128_2
5562
* =0 if *h128_1 == *h128_2 */
5563
/*! @ingroup xxh3_family */
5564
XXH_PUBLIC_API int XXH128_cmp(const void* h128_1, const void* h128_2)
5565
{
5566
XXH128_hash_t const h1 = *(const XXH128_hash_t*)h128_1;
5567
XXH128_hash_t const h2 = *(const XXH128_hash_t*)h128_2;
5568
int const hcmp = (h1.high64 > h2.high64) - (h2.high64 > h1.high64);
5569
/* note : bets that, in most cases, hash values are different */
5570
if (hcmp) return hcmp;
5571
return (h1.low64 > h2.low64) - (h2.low64 > h1.low64);
5572
}
5573
5574
5575
/*====== Canonical representation ======*/
5576
/*! @ingroup xxh3_family */
5577
XXH_PUBLIC_API void
5578
XXH128_canonicalFromHash(XXH128_canonical_t* dst, XXH128_hash_t hash)
5579
{
5580
XXH_STATIC_ASSERT(sizeof(XXH128_canonical_t) == sizeof(XXH128_hash_t));
5581
if (XXH_CPU_LITTLE_ENDIAN) {
5582
hash.high64 = XXH_swap64(hash.high64);
5583
hash.low64 = XXH_swap64(hash.low64);
5584
}
5585
XXH_memcpy(dst, &hash.high64, sizeof(hash.high64));
5586
XXH_memcpy((char*)dst + sizeof(hash.high64), &hash.low64, sizeof(hash.low64));
5587
}
5588
5589
/*! @ingroup xxh3_family */
5590
XXH_PUBLIC_API XXH128_hash_t
5591
XXH128_hashFromCanonical(const XXH128_canonical_t* src)
5592
{
5593
XXH128_hash_t h;
5594
h.high64 = XXH_readBE64(src);
5595
h.low64 = XXH_readBE64(src->digest + 8);
5596
return h;
5597
}
5598
5599
5600
5601
/* ==========================================
5602
* Secret generators
5603
* ==========================================
5604
*/
5605
#define XXH_MIN(x, y) (((x) > (y)) ? (y) : (x))
5606
5607
XXH_FORCE_INLINE void XXH3_combine16(void* dst, XXH128_hash_t h128)
5608
{
5609
XXH_writeLE64( dst, XXH_readLE64(dst) ^ h128.low64 );
5610
XXH_writeLE64( (char*)dst+8, XXH_readLE64((char*)dst+8) ^ h128.high64 );
5611
}
5612
5613
/*! @ingroup xxh3_family */
5614
XXH_PUBLIC_API XXH_errorcode
5615
XXH3_generateSecret(void* secretBuffer, size_t secretSize, const void* customSeed, size_t customSeedSize)
5616
{
5617
#if (XXH_DEBUGLEVEL >= 1)
5618
XXH_ASSERT(secretBuffer != NULL);
5619
XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
5620
#else
5621
/* production mode, assert() are disabled */
5622
if (secretBuffer == NULL) return XXH_ERROR;
5623
if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
5624
#endif
5625
5626
if (customSeedSize == 0) {
5627
customSeed = XXH3_kSecret;
5628
customSeedSize = XXH_SECRET_DEFAULT_SIZE;
5629
}
5630
#if (XXH_DEBUGLEVEL >= 1)
5631
XXH_ASSERT(customSeed != NULL);
5632
#else
5633
if (customSeed == NULL) return XXH_ERROR;
5634
#endif
5635
5636
/* Fill secretBuffer with a copy of customSeed - repeat as needed */
5637
{ size_t pos = 0;
5638
while (pos < secretSize) {
5639
size_t const toCopy = XXH_MIN((secretSize - pos), customSeedSize);
5640
memcpy((char*)secretBuffer + pos, customSeed, toCopy);
5641
pos += toCopy;
5642
} }
5643
5644
{ size_t const nbSeg16 = secretSize / 16;
5645
size_t n;
5646
XXH128_canonical_t scrambler;
5647
XXH128_canonicalFromHash(&scrambler, XXH128(customSeed, customSeedSize, 0));
5648
for (n=0; n<nbSeg16; n++) {
5649
XXH128_hash_t const h128 = XXH128(&scrambler, sizeof(scrambler), n);
5650
XXH3_combine16((char*)secretBuffer + n*16, h128);
5651
}
5652
/* last segment */
5653
XXH3_combine16((char*)secretBuffer + secretSize - 16, XXH128_hashFromCanonical(&scrambler));
5654
}
5655
return XXH_OK;
5656
}
5657
5658
/*! @ingroup xxh3_family */
5659
XXH_PUBLIC_API void
5660
XXH3_generateSecret_fromSeed(void* secretBuffer, XXH64_hash_t seed)
5661
{
5662
XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
5663
XXH3_initCustomSecret(secret, seed);
5664
XXH_ASSERT(secretBuffer != NULL);
5665
memcpy(secretBuffer, secret, XXH_SECRET_DEFAULT_SIZE);
5666
}
5667
5668
5669
5670
/* Pop our optimization override from above */
5671
#if XXH_VECTOR == XXH_AVX2 /* AVX2 */ \
5672
&& defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
5673
&& defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) /* respect -O0 and -Os */
5674
# pragma GCC pop_options
5675
#endif
5676
5677
#endif /* XXH_NO_LONG_LONG */
5678
5679
#endif /* XXH_NO_XXH3 */
5680
5681
/*!
5682
* @}
5683
*/
5684
#endif /* XXH_IMPLEMENTATION */
5685
5686
5687
#if defined (__cplusplus)
5688
}
5689
#endif
5690
5691