xref: /PHP-8.2/ext/hash/xxhash/xxhash.h (revision 76386405)
1 /*
2  * xxHash - Extremely Fast Hash algorithm
3  * Header File
4  * Copyright (C) 2012-2020 Yann Collet
5  *
6  * BSD 2-Clause License (https://www.opensource.org/licenses/bsd-license.php)
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are
10  * met:
11  *
12  *    * Redistributions of source code must retain the above copyright
13  *      notice, this list of conditions and the following disclaimer.
14  *    * Redistributions in binary form must reproduce the above
15  *      copyright notice, this list of conditions and the following disclaimer
16  *      in the documentation and/or other materials provided with the
17  *      distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  * You can contact the author at:
32  *   - xxHash homepage: https://www.xxhash.com
33  *   - xxHash source repository: https://github.com/Cyan4973/xxHash
34  */
35 /*!
36  * @mainpage xxHash
37  *
38  * @file xxhash.h
39  * xxHash prototypes and implementation
40  */
41 /* TODO: update */
42 /* Notice extracted from xxHash homepage:
43 
44 xxHash is an extremely fast hash algorithm, running at RAM speed limits.
45 It also successfully passes all tests from the SMHasher suite.
46 
47 Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
48 
49 Name            Speed       Q.Score   Author
50 xxHash          5.4 GB/s     10
51 CrapWow         3.2 GB/s      2       Andrew
52 MurmurHash 3a   2.7 GB/s     10       Austin Appleby
53 SpookyHash      2.0 GB/s     10       Bob Jenkins
54 SBox            1.4 GB/s      9       Bret Mulvey
55 Lookup3         1.2 GB/s      9       Bob Jenkins
56 SuperFastHash   1.2 GB/s      1       Paul Hsieh
57 CityHash64      1.05 GB/s    10       Pike & Alakuijala
58 FNV             0.55 GB/s     5       Fowler, Noll, Vo
59 CRC32           0.43 GB/s     9
60 MD5-32          0.33 GB/s    10       Ronald L. Rivest
61 SHA1-32         0.28 GB/s    10
62 
63 Q.Score is a measure of quality of the hash function.
64 It depends on successfully passing SMHasher test set.
65 10 is a perfect score.
66 
67 Note: SMHasher's CRC32 implementation is not the fastest one.
68 Other speed-oriented implementations can be faster,
69 especially in combination with PCLMUL instruction:
70 https://fastcompression.blogspot.com/2019/03/presenting-xxh3.html?showComment=1552696407071#c3490092340461170735
71 
72 A 64-bit version, named XXH64, is available since r35.
73 It offers much better speed, but for 64-bit applications only.
74 Name     Speed on 64 bits    Speed on 32 bits
75 XXH64       13.8 GB/s            1.9 GB/s
76 XXH32        6.8 GB/s            6.0 GB/s
77 */
78 
79 #if defined (__cplusplus)
80 extern "C" {
81 #endif
82 
83 /* ****************************
84  *  INLINE mode
85  ******************************/
86 /*!
87  * XXH_INLINE_ALL (and XXH_PRIVATE_API)
88  * Use these build macros to inline xxhash into the target unit.
89  * Inlining improves performance on small inputs, especially when the length is
90  * expressed as a compile-time constant:
91  *
92  *      https://fastcompression.blogspot.com/2018/03/xxhash-for-small-keys-impressive-power.html
93  *
94  * It also keeps xxHash symbols private to the unit, so they are not exported.
95  *
96  * Usage:
97  *     #define XXH_INLINE_ALL
98  *     #include "xxhash.h"
99  *
100  * Do not compile and link xxhash.o as a separate object, as it is not useful.
101  */
102 #if (defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)) \
103     && !defined(XXH_INLINE_ALL_31684351384)
104    /* this section should be traversed only once */
105 #  define XXH_INLINE_ALL_31684351384
106    /* give access to the advanced API, required to compile implementations */
107 #  undef XXH_STATIC_LINKING_ONLY   /* avoid macro redef */
108 #  define XXH_STATIC_LINKING_ONLY
109    /* make all functions private */
110 #  undef XXH_PUBLIC_API
111 #  if defined(__GNUC__)
112 #    define XXH_PUBLIC_API static __inline __attribute__((unused))
113 #  elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
114 #    define XXH_PUBLIC_API static inline
115 #  elif defined(_MSC_VER)
116 #    define XXH_PUBLIC_API static __inline
117 #  else
118      /* note: this version may generate warnings for unused static functions */
119 #    define XXH_PUBLIC_API static
120 #  endif
121 
122    /*
123     * This part deals with the special case where a unit wants to inline xxHash,
124     * but "xxhash.h" has previously been included without XXH_INLINE_ALL,
125     * such as part of some previously included *.h header file.
126     * Without further action, the new include would just be ignored,
127     * and functions would effectively _not_ be inlined (silent failure).
128     * The following macros solve this situation by prefixing all inlined names,
129     * avoiding naming collision with previous inclusions.
130     */
131    /* Before that, we unconditionally #undef all symbols,
132     * in case they were already defined with XXH_NAMESPACE.
133     * They will then be redefined for XXH_INLINE_ALL
134     */
135 #  undef XXH_versionNumber
136     /* XXH32 */
137 #  undef XXH32
138 #  undef XXH32_createState
139 #  undef XXH32_freeState
140 #  undef XXH32_reset
141 #  undef XXH32_update
142 #  undef XXH32_digest
143 #  undef XXH32_copyState
144 #  undef XXH32_canonicalFromHash
145 #  undef XXH32_hashFromCanonical
146     /* XXH64 */
147 #  undef XXH64
148 #  undef XXH64_createState
149 #  undef XXH64_freeState
150 #  undef XXH64_reset
151 #  undef XXH64_update
152 #  undef XXH64_digest
153 #  undef XXH64_copyState
154 #  undef XXH64_canonicalFromHash
155 #  undef XXH64_hashFromCanonical
156     /* XXH3_64bits */
157 #  undef XXH3_64bits
158 #  undef XXH3_64bits_withSecret
159 #  undef XXH3_64bits_withSeed
160 #  undef XXH3_64bits_withSecretandSeed
161 #  undef XXH3_createState
162 #  undef XXH3_freeState
163 #  undef XXH3_copyState
164 #  undef XXH3_64bits_reset
165 #  undef XXH3_64bits_reset_withSeed
166 #  undef XXH3_64bits_reset_withSecret
167 #  undef XXH3_64bits_update
168 #  undef XXH3_64bits_digest
169 #  undef XXH3_generateSecret
170     /* XXH3_128bits */
171 #  undef XXH128
172 #  undef XXH3_128bits
173 #  undef XXH3_128bits_withSeed
174 #  undef XXH3_128bits_withSecret
175 #  undef XXH3_128bits_reset
176 #  undef XXH3_128bits_reset_withSeed
177 #  undef XXH3_128bits_reset_withSecret
178 #  undef XXH3_128bits_reset_withSecretandSeed
179 #  undef XXH3_128bits_update
180 #  undef XXH3_128bits_digest
181 #  undef XXH128_isEqual
182 #  undef XXH128_cmp
183 #  undef XXH128_canonicalFromHash
184 #  undef XXH128_hashFromCanonical
185     /* Finally, free the namespace itself */
186 #  undef XXH_NAMESPACE
187 
188     /* employ the namespace for XXH_INLINE_ALL */
189 #  define XXH_NAMESPACE XXH_INLINE_
190    /*
191     * Some identifiers (enums, type names) are not symbols,
192     * but they must nonetheless be renamed to avoid redeclaration.
193     * Alternative solution: do not redeclare them.
194     * However, this requires some #ifdefs, and has a more dispersed impact.
195     * Meanwhile, renaming can be achieved in a single place.
196     */
197 #  define XXH_IPREF(Id)   XXH_NAMESPACE ## Id
198 #  define XXH_OK XXH_IPREF(XXH_OK)
199 #  define XXH_ERROR XXH_IPREF(XXH_ERROR)
200 #  define XXH_errorcode XXH_IPREF(XXH_errorcode)
201 #  define XXH32_canonical_t  XXH_IPREF(XXH32_canonical_t)
202 #  define XXH64_canonical_t  XXH_IPREF(XXH64_canonical_t)
203 #  define XXH128_canonical_t XXH_IPREF(XXH128_canonical_t)
204 #  define XXH32_state_s XXH_IPREF(XXH32_state_s)
205 #  define XXH32_state_t XXH_IPREF(XXH32_state_t)
206 #  define XXH64_state_s XXH_IPREF(XXH64_state_s)
207 #  define XXH64_state_t XXH_IPREF(XXH64_state_t)
208 #  define XXH3_state_s  XXH_IPREF(XXH3_state_s)
209 #  define XXH3_state_t  XXH_IPREF(XXH3_state_t)
210 #  define XXH128_hash_t XXH_IPREF(XXH128_hash_t)
211    /* Ensure the header is parsed again, even if it was previously included */
212 #  undef XXHASH_H_5627135585666179
213 #  undef XXHASH_H_STATIC_13879238742
214 #endif /* XXH_INLINE_ALL || XXH_PRIVATE_API */
215 
216 
217 
218 /* ****************************************************************
219  *  Stable API
220  *****************************************************************/
221 #ifndef XXHASH_H_5627135585666179
222 #define XXHASH_H_5627135585666179 1
223 
224 
225 /*!
226  * @defgroup public Public API
227  * Contains details on the public xxHash functions.
228  * @{
229  */
230 /* specific declaration modes for Windows */
231 #if !defined(XXH_INLINE_ALL) && !defined(XXH_PRIVATE_API)
232 #  if defined(WIN32) && defined(_MSC_VER) && (defined(XXH_IMPORT) || defined(XXH_EXPORT))
233 #    ifdef XXH_EXPORT
234 #      define XXH_PUBLIC_API __declspec(dllexport)
235 #    elif XXH_IMPORT
236 #      define XXH_PUBLIC_API __declspec(dllimport)
237 #    endif
238 #  else
239 #    define XXH_PUBLIC_API   /* do nothing */
240 #  endif
241 #endif
242 
243 #ifdef XXH_DOXYGEN
244 /*!
245  * @brief Emulate a namespace by transparently prefixing all symbols.
246  *
247  * If you want to include _and expose_ xxHash functions from within your own
248  * library, but also want to avoid symbol collisions with other libraries which
249  * may also include xxHash, you can use XXH_NAMESPACE to automatically prefix
250  * any public symbol from xxhash library with the value of XXH_NAMESPACE
251  * (therefore, avoid empty or numeric values).
252  *
253  * Note that no change is required within the calling program as long as it
254  * includes `xxhash.h`: Regular symbol names will be automatically translated
255  * by this header.
256  */
257 #  define XXH_NAMESPACE /* YOUR NAME HERE */
258 #  undef XXH_NAMESPACE
259 #endif
260 
261 #ifdef XXH_NAMESPACE
262 #  define XXH_CAT(A,B) A##B
263 #  define XXH_NAME2(A,B) XXH_CAT(A,B)
264 #  define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber)
265 /* XXH32 */
266 #  define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
267 #  define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
268 #  define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
269 #  define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
270 #  define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
271 #  define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
272 #  define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState)
273 #  define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash)
274 #  define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical)
275 /* XXH64 */
276 #  define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
277 #  define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
278 #  define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
279 #  define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
280 #  define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
281 #  define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
282 #  define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState)
283 #  define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash)
284 #  define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical)
285 /* XXH3_64bits */
286 #  define XXH3_64bits XXH_NAME2(XXH_NAMESPACE, XXH3_64bits)
287 #  define XXH3_64bits_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSecret)
288 #  define XXH3_64bits_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSeed)
289 #  define XXH3_64bits_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_withSecretandSeed)
290 #  define XXH3_createState XXH_NAME2(XXH_NAMESPACE, XXH3_createState)
291 #  define XXH3_freeState XXH_NAME2(XXH_NAMESPACE, XXH3_freeState)
292 #  define XXH3_copyState XXH_NAME2(XXH_NAMESPACE, XXH3_copyState)
293 #  define XXH3_64bits_reset XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset)
294 #  define XXH3_64bits_reset_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSeed)
295 #  define XXH3_64bits_reset_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSecret)
296 #  define XXH3_64bits_reset_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_reset_withSecretandSeed)
297 #  define XXH3_64bits_update XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_update)
298 #  define XXH3_64bits_digest XXH_NAME2(XXH_NAMESPACE, XXH3_64bits_digest)
299 #  define XXH3_generateSecret XXH_NAME2(XXH_NAMESPACE, XXH3_generateSecret)
300 #  define XXH3_generateSecret_fromSeed XXH_NAME2(XXH_NAMESPACE, XXH3_generateSecret_fromSeed)
301 /* XXH3_128bits */
302 #  define XXH128 XXH_NAME2(XXH_NAMESPACE, XXH128)
303 #  define XXH3_128bits XXH_NAME2(XXH_NAMESPACE, XXH3_128bits)
304 #  define XXH3_128bits_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSeed)
305 #  define XXH3_128bits_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSecret)
306 #  define XXH3_128bits_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_withSecretandSeed)
307 #  define XXH3_128bits_reset XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset)
308 #  define XXH3_128bits_reset_withSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSeed)
309 #  define XXH3_128bits_reset_withSecret XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSecret)
310 #  define XXH3_128bits_reset_withSecretandSeed XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_reset_withSecretandSeed)
311 #  define XXH3_128bits_update XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_update)
312 #  define XXH3_128bits_digest XXH_NAME2(XXH_NAMESPACE, XXH3_128bits_digest)
313 #  define XXH128_isEqual XXH_NAME2(XXH_NAMESPACE, XXH128_isEqual)
314 #  define XXH128_cmp     XXH_NAME2(XXH_NAMESPACE, XXH128_cmp)
315 #  define XXH128_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH128_canonicalFromHash)
316 #  define XXH128_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH128_hashFromCanonical)
317 #endif
318 
319 
320 /* *************************************
321 *  Version
322 ***************************************/
323 #define XXH_VERSION_MAJOR    0
324 #define XXH_VERSION_MINOR    8
325 #define XXH_VERSION_RELEASE  1
326 #define XXH_VERSION_NUMBER  (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
327 
328 /*!
329  * @brief Obtains the xxHash version.
330  *
331  * This is mostly useful when xxHash is compiled as a shared library,
332  * since the returned value comes from the library, as opposed to header file.
333  *
334  * @return `XXH_VERSION_NUMBER` of the invoked library.
335  */
336 XXH_PUBLIC_API unsigned XXH_versionNumber (void);
337 
338 
339 /* ****************************
340 *  Common basic types
341 ******************************/
342 #include <stddef.h>   /* size_t */
343 typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
344 
345 
346 /*-**********************************************************************
347 *  32-bit hash
348 ************************************************************************/
349 #if defined(XXH_DOXYGEN) /* Don't show <stdint.h> include */
350 /*!
351  * @brief An unsigned 32-bit integer.
352  *
353  * Not necessarily defined to `uint32_t` but functionally equivalent.
354  */
355 typedef uint32_t XXH32_hash_t;
356 
357 #elif !defined (__VMS) \
358   && (defined (__cplusplus) \
359   || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
360 #   include <stdint.h>
361     typedef uint32_t XXH32_hash_t;
362 
363 #else
364 #   include <limits.h>
365 #   if UINT_MAX == 0xFFFFFFFFUL
366       typedef unsigned int XXH32_hash_t;
367 #   else
368 #     if ULONG_MAX == 0xFFFFFFFFUL
369         typedef unsigned long XXH32_hash_t;
370 #     else
371 #       error "unsupported platform: need a 32-bit type"
372 #     endif
373 #   endif
374 #endif
375 
376 /*!
377  * @}
378  *
379  * @defgroup xxh32_family XXH32 family
380  * @ingroup public
381  * Contains functions used in the classic 32-bit xxHash algorithm.
382  *
383  * @note
384  *   XXH32 is useful for older platforms, with no or poor 64-bit performance.
385  *   Note that @ref xxh3_family provides competitive speed
386  *   for both 32-bit and 64-bit systems, and offers true 64/128 bit hash results.
387  *
388  * @see @ref xxh64_family, @ref xxh3_family : Other xxHash families
389  * @see @ref xxh32_impl for implementation details
390  * @{
391  */
392 
393 /*!
394  * @brief Calculates the 32-bit hash of @p input using xxHash32.
395  *
396  * Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark): 5.4 GB/s
397  *
398  * @param input The block of data to be hashed, at least @p length bytes in size.
399  * @param length The length of @p input, in bytes.
400  * @param seed The 32-bit seed to alter the hash's output predictably.
401  *
402  * @pre
403  *   The memory between @p input and @p input + @p length must be valid,
404  *   readable, contiguous memory. However, if @p length is `0`, @p input may be
405  *   `NULL`. In C++, this also must be *TriviallyCopyable*.
406  *
407  * @return The calculated 32-bit hash value.
408  *
409  * @see
410  *    XXH64(), XXH3_64bits_withSeed(), XXH3_128bits_withSeed(), XXH128():
411  *    Direct equivalents for the other variants of xxHash.
412  * @see
413  *    XXH32_createState(), XXH32_update(), XXH32_digest(): Streaming version.
414  */
415 XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, XXH32_hash_t seed);
416 
417 /*!
418  * Streaming functions generate the xxHash value from an incremental input.
419  * This method is slower than single-call functions, due to state management.
420  * For small inputs, prefer `XXH32()` and `XXH64()`, which are better optimized.
421  *
422  * An XXH state must first be allocated using `XXH*_createState()`.
423  *
424  * Start a new hash by initializing the state with a seed using `XXH*_reset()`.
425  *
426  * Then, feed the hash state by calling `XXH*_update()` as many times as necessary.
427  *
428  * The function returns an error code, with 0 meaning OK, and any other value
429  * meaning there is an error.
430  *
431  * Finally, a hash value can be produced anytime, by using `XXH*_digest()`.
432  * This function returns the nn-bits hash as an int or long long.
433  *
434  * It's still possible to continue inserting input into the hash state after a
435  * digest, and generate new hash values later on by invoking `XXH*_digest()`.
436  *
437  * When done, release the state using `XXH*_freeState()`.
438  *
439  * Example code for incrementally hashing a file:
440  * @code{.c}
441  *    #include <stdio.h>
442  *    #include <xxhash.h>
443  *    #define BUFFER_SIZE 256
444  *
445  *    // Note: XXH64 and XXH3 use the same interface.
446  *    XXH32_hash_t
447  *    hashFile(FILE* stream)
448  *    {
449  *        XXH32_state_t* state;
450  *        unsigned char buf[BUFFER_SIZE];
451  *        size_t amt;
452  *        XXH32_hash_t hash;
453  *
454  *        state = XXH32_createState();       // Create a state
455  *        assert(state != NULL);             // Error check here
456  *        XXH32_reset(state, 0xbaad5eed);    // Reset state with our seed
457  *        while ((amt = fread(buf, 1, sizeof(buf), stream)) != 0) {
458  *            XXH32_update(state, buf, amt); // Hash the file in chunks
459  *        }
460  *        hash = XXH32_digest(state);        // Finalize the hash
461  *        XXH32_freeState(state);            // Clean up
462  *        return hash;
463  *    }
464  * @endcode
465  */
466 
467 /*!
468  * @typedef struct XXH32_state_s XXH32_state_t
469  * @brief The opaque state struct for the XXH32 streaming API.
470  *
471  * @see XXH32_state_s for details.
472  */
473 typedef struct XXH32_state_s XXH32_state_t;
474 
475 /*!
476  * @brief Allocates an @ref XXH32_state_t.
477  *
478  * Must be freed with XXH32_freeState().
479  * @return An allocated XXH32_state_t on success, `NULL` on failure.
480  */
481 XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void);
482 /*!
483  * @brief Frees an @ref XXH32_state_t.
484  *
485  * Must be allocated with XXH32_createState().
486  * @param statePtr A pointer to an @ref XXH32_state_t allocated with @ref XXH32_createState().
487  * @return XXH_OK.
488  */
489 XXH_PUBLIC_API XXH_errorcode  XXH32_freeState(XXH32_state_t* statePtr);
490 /*!
491  * @brief Copies one @ref XXH32_state_t to another.
492  *
493  * @param dst_state The state to copy to.
494  * @param src_state The state to copy from.
495  * @pre
496  *   @p dst_state and @p src_state must not be `NULL` and must not overlap.
497  */
498 XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state);
499 
500 /*!
501  * @brief Resets an @ref XXH32_state_t to begin a new hash.
502  *
503  * This function resets and seeds a state. Call it before @ref XXH32_update().
504  *
505  * @param statePtr The state struct to reset.
506  * @param seed The 32-bit seed to alter the hash result predictably.
507  *
508  * @pre
509  *   @p statePtr must not be `NULL`.
510  *
511  * @return @ref XXH_OK on success, @ref XXH_ERROR on failure.
512  */
513 XXH_PUBLIC_API XXH_errorcode XXH32_reset  (XXH32_state_t* statePtr, XXH32_hash_t seed);
514 
515 /*!
516  * @brief Consumes a block of @p input to an @ref XXH32_state_t.
517  *
518  * Call this to incrementally consume blocks of data.
519  *
520  * @param statePtr The state struct to update.
521  * @param input The block of data to be hashed, at least @p length bytes in size.
522  * @param length The length of @p input, in bytes.
523  *
524  * @pre
525  *   @p statePtr must not be `NULL`.
526  * @pre
527  *   The memory between @p input and @p input + @p length must be valid,
528  *   readable, contiguous memory. However, if @p length is `0`, @p input may be
529  *   `NULL`. In C++, this also must be *TriviallyCopyable*.
530  *
531  * @return @ref XXH_OK on success, @ref XXH_ERROR on failure.
532  */
533 XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
534 
535 /*!
536  * @brief Returns the calculated hash value from an @ref XXH32_state_t.
537  *
538  * @note
539  *   Calling XXH32_digest() will not affect @p statePtr, so you can update,
540  *   digest, and update again.
541  *
542  * @param statePtr The state struct to calculate the hash from.
543  *
544  * @pre
545  *  @p statePtr must not be `NULL`.
546  *
547  * @return The calculated xxHash32 value from that state.
548  */
549 XXH_PUBLIC_API XXH32_hash_t  XXH32_digest (const XXH32_state_t* statePtr);
550 
551 /*******   Canonical representation   *******/
552 
553 /*
554  * The default return values from XXH functions are unsigned 32 and 64 bit
555  * integers.
556  * This the simplest and fastest format for further post-processing.
557  *
558  * However, this leaves open the question of what is the order on the byte level,
559  * since little and big endian conventions will store the same number differently.
560  *
561  * The canonical representation settles this issue by mandating big-endian
562  * convention, the same convention as human-readable numbers (large digits first).
563  *
564  * When writing hash values to storage, sending them over a network, or printing
565  * them, it's highly recommended to use the canonical representation to ensure
566  * portability across a wider range of systems, present and future.
567  *
568  * The following functions allow transformation of hash values to and from
569  * canonical format.
570  */
571 
572 /*!
573  * @brief Canonical (big endian) representation of @ref XXH32_hash_t.
574  */
575 typedef struct {
576     unsigned char digest[4]; /*!< Hash bytes, big endian */
577 } XXH32_canonical_t;
578 
579 /*!
580  * @brief Converts an @ref XXH32_hash_t to a big endian @ref XXH32_canonical_t.
581  *
582  * @param dst The @ref XXH32_canonical_t pointer to be stored to.
583  * @param hash The @ref XXH32_hash_t to be converted.
584  *
585  * @pre
586  *   @p dst must not be `NULL`.
587  */
588 XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
589 
590 /*!
591  * @brief Converts an @ref XXH32_canonical_t to a native @ref XXH32_hash_t.
592  *
593  * @param src The @ref XXH32_canonical_t to convert.
594  *
595  * @pre
596  *   @p src must not be `NULL`.
597  *
598  * @return The converted hash.
599  */
600 XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src);
601 
602 
603 #ifdef __has_attribute
604 # define XXH_HAS_ATTRIBUTE(x) __has_attribute(x)
605 #else
606 # define XXH_HAS_ATTRIBUTE(x) 0
607 #endif
608 
609 /* C-language Attributes are added in C23. */
610 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
611 # define XXH_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
612 #else
613 # define XXH_HAS_C_ATTRIBUTE(x) 0
614 #endif
615 
616 #if defined(__cplusplus) && defined(__has_cpp_attribute)
617 # define XXH_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
618 #else
619 # define XXH_HAS_CPP_ATTRIBUTE(x) 0
620 #endif
621 
622 /*
623 Define XXH_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute
624 introduced in CPP17 and C23.
625 CPP17 : https://en.cppreference.com/w/cpp/language/attributes/fallthrough
626 C23   : https://en.cppreference.com/w/c/language/attributes/fallthrough
627 */
628 #if XXH_HAS_C_ATTRIBUTE(x)
629 # define XXH_FALLTHROUGH [[fallthrough]]
630 #elif XXH_HAS_CPP_ATTRIBUTE(x)
631 # define XXH_FALLTHROUGH [[fallthrough]]
632 #elif XXH_HAS_ATTRIBUTE(__fallthrough__)
633 # define XXH_FALLTHROUGH __attribute__ ((fallthrough))
634 #else
635 # define XXH_FALLTHROUGH
636 #endif
637 
638 /*!
639  * @}
640  * @ingroup public
641  * @{
642  */
643 
644 #ifndef XXH_NO_LONG_LONG
645 /*-**********************************************************************
646 *  64-bit hash
647 ************************************************************************/
648 #if defined(XXH_DOXYGEN) /* don't include <stdint.h> */
649 /*!
650  * @brief An unsigned 64-bit integer.
651  *
652  * Not necessarily defined to `uint64_t` but functionally equivalent.
653  */
654 typedef uint64_t XXH64_hash_t;
655 #elif !defined (__VMS) \
656   && (defined (__cplusplus) \
657   || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
658 #  include <stdint.h>
659    typedef uint64_t XXH64_hash_t;
660 #else
661 #  include <limits.h>
662 #  if defined(__LP64__) && ULONG_MAX == 0xFFFFFFFFFFFFFFFFULL
663      /* LP64 ABI says uint64_t is unsigned long */
664      typedef unsigned long XXH64_hash_t;
665 #  else
666      /* the following type must have a width of 64-bit */
667      typedef unsigned long long XXH64_hash_t;
668 #  endif
669 #endif
670 
671 /*!
672  * @}
673  *
674  * @defgroup xxh64_family XXH64 family
675  * @ingroup public
676  * @{
677  * Contains functions used in the classic 64-bit xxHash algorithm.
678  *
679  * @note
680  *   XXH3 provides competitive speed for both 32-bit and 64-bit systems,
681  *   and offers true 64/128 bit hash results.
682  *   It provides better speed for systems with vector processing capabilities.
683  */
684 
685 
686 /*!
687  * @brief Calculates the 64-bit hash of @p input using xxHash64.
688  *
689  * This function usually runs faster on 64-bit systems, but slower on 32-bit
690  * systems (see benchmark).
691  *
692  * @param input The block of data to be hashed, at least @p length bytes in size.
693  * @param length The length of @p input, in bytes.
694  * @param seed The 64-bit seed to alter the hash's output predictably.
695  *
696  * @pre
697  *   The memory between @p input and @p input + @p length must be valid,
698  *   readable, contiguous memory. However, if @p length is `0`, @p input may be
699  *   `NULL`. In C++, this also must be *TriviallyCopyable*.
700  *
701  * @return The calculated 64-bit hash.
702  *
703  * @see
704  *    XXH32(), XXH3_64bits_withSeed(), XXH3_128bits_withSeed(), XXH128():
705  *    Direct equivalents for the other variants of xxHash.
706  * @see
707  *    XXH64_createState(), XXH64_update(), XXH64_digest(): Streaming version.
708  */
709 XXH_PUBLIC_API XXH64_hash_t XXH64(const void* input, size_t length, XXH64_hash_t seed);
710 
711 /*******   Streaming   *******/
712 /*!
713  * @brief The opaque state struct for the XXH64 streaming API.
714  *
715  * @see XXH64_state_s for details.
716  */
717 typedef struct XXH64_state_s XXH64_state_t;   /* incomplete type */
718 XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void);
719 XXH_PUBLIC_API XXH_errorcode  XXH64_freeState(XXH64_state_t* statePtr);
720 XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state);
721 
722 XXH_PUBLIC_API XXH_errorcode XXH64_reset  (XXH64_state_t* statePtr, XXH64_hash_t seed);
723 XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
724 XXH_PUBLIC_API XXH64_hash_t  XXH64_digest (const XXH64_state_t* statePtr);
725 
726 /*******   Canonical representation   *******/
727 typedef struct { unsigned char digest[sizeof(XXH64_hash_t)]; } XXH64_canonical_t;
728 XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
729 XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src);
730 
731 /*!
732  * @}
733  * ************************************************************************
734  * @defgroup xxh3_family XXH3 family
735  * @ingroup public
736  * @{
737  *
738  * XXH3 is a more recent hash algorithm featuring:
739  *  - Improved speed for both small and large inputs
740  *  - True 64-bit and 128-bit outputs
741  *  - SIMD acceleration
742  *  - Improved 32-bit viability
743  *
744  * Speed analysis methodology is explained here:
745  *
746  *    https://fastcompression.blogspot.com/2019/03/presenting-xxh3.html
747  *
748  * Compared to XXH64, expect XXH3 to run approximately
749  * ~2x faster on large inputs and >3x faster on small ones,
750  * exact differences vary depending on platform.
751  *
752  * XXH3's speed benefits greatly from SIMD and 64-bit arithmetic,
753  * but does not require it.
754  * Any 32-bit and 64-bit targets that can run XXH32 smoothly
755  * can run XXH3 at competitive speeds, even without vector support.
756  * Further details are explained in the implementation.
757  *
758  * Optimized implementations are provided for AVX512, AVX2, SSE2, NEON, POWER8,
759  * ZVector and scalar targets. This can be controlled via the XXH_VECTOR macro.
760  *
761  * XXH3 implementation is portable:
762  * it has a generic C90 formulation that can be compiled on any platform,
763  * all implementations generage exactly the same hash value on all platforms.
764  * Starting from v0.8.0, it's also labelled "stable", meaning that
765  * any future version will also generate the same hash value.
766  *
767  * XXH3 offers 2 variants, _64bits and _128bits.
768  *
769  * When only 64 bits are needed, prefer invoking the _64bits variant, as it
770  * reduces the amount of mixing, resulting in faster speed on small inputs.
771  * It's also generally simpler to manipulate a scalar return type than a struct.
772  *
773  * The API supports one-shot hashing, streaming mode, and custom secrets.
774  */
775 
776 /*-**********************************************************************
777 *  XXH3 64-bit variant
778 ************************************************************************/
779 
780 /* XXH3_64bits():
781  * default 64-bit variant, using default secret and default seed of 0.
782  * It's the fastest variant. */
783 XXH_PUBLIC_API XXH64_hash_t XXH3_64bits(const void* data, size_t len);
784 
785 /*
786  * XXH3_64bits_withSeed():
787  * This variant generates a custom secret on the fly
788  * based on default secret altered using the `seed` value.
789  * While this operation is decently fast, note that it's not completely free.
790  * Note: seed==0 produces the same results as XXH3_64bits().
791  */
792 XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_withSeed(const void* data, size_t len, XXH64_hash_t seed);
793 
794 /*!
795  * The bare minimum size for a custom secret.
796  *
797  * @see
798  *  XXH3_64bits_withSecret(), XXH3_64bits_reset_withSecret(),
799  *  XXH3_128bits_withSecret(), XXH3_128bits_reset_withSecret().
800  */
801 #define XXH3_SECRET_SIZE_MIN 136
802 
803 /*
804  * XXH3_64bits_withSecret():
805  * It's possible to provide any blob of bytes as a "secret" to generate the hash.
806  * This makes it more difficult for an external actor to prepare an intentional collision.
807  * The main condition is that secretSize *must* be large enough (>= XXH3_SECRET_SIZE_MIN).
808  * However, the quality of the secret impacts the dispersion of the hash algorithm.
809  * Therefore, the secret _must_ look like a bunch of random bytes.
810  * Avoid "trivial" or structured data such as repeated sequences or a text document.
811  * Whenever in doubt about the "randomness" of the blob of bytes,
812  * consider employing "XXH3_generateSecret()" instead (see below).
813  * It will generate a proper high entropy secret derived from the blob of bytes.
814  * Another advantage of using XXH3_generateSecret() is that
815  * it guarantees that all bits within the initial blob of bytes
816  * will impact every bit of the output.
817  * This is not necessarily the case when using the blob of bytes directly
818  * because, when hashing _small_ inputs, only a portion of the secret is employed.
819  */
820 XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_withSecret(const void* data, size_t len, const void* secret, size_t secretSize);
821 
822 
823 /*******   Streaming   *******/
824 /*
825  * Streaming requires state maintenance.
826  * This operation costs memory and CPU.
827  * As a consequence, streaming is slower than one-shot hashing.
828  * For better performance, prefer one-shot functions whenever applicable.
829  */
830 
831 /*!
832  * @brief The state struct for the XXH3 streaming API.
833  *
834  * @see XXH3_state_s for details.
835  */
836 typedef struct XXH3_state_s XXH3_state_t;
837 XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void);
838 XXH_PUBLIC_API XXH_errorcode XXH3_freeState(XXH3_state_t* statePtr);
839 XXH_PUBLIC_API void XXH3_copyState(XXH3_state_t* dst_state, const XXH3_state_t* src_state);
840 
841 /*
842  * XXH3_64bits_reset():
843  * Initialize with default parameters.
844  * digest will be equivalent to `XXH3_64bits()`.
845  */
846 XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset(XXH3_state_t* statePtr);
847 /*
848  * XXH3_64bits_reset_withSeed():
849  * Generate a custom secret from `seed`, and store it into `statePtr`.
850  * digest will be equivalent to `XXH3_64bits_withSeed()`.
851  */
852 XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed);
853 /*
854  * XXH3_64bits_reset_withSecret():
855  * `secret` is referenced, it _must outlive_ the hash streaming session.
856  * Similar to one-shot API, `secretSize` must be >= `XXH3_SECRET_SIZE_MIN`,
857  * and the quality of produced hash values depends on secret's entropy
858  * (secret's content should look like a bunch of random bytes).
859  * When in doubt about the randomness of a candidate `secret`,
860  * consider employing `XXH3_generateSecret()` instead (see below).
861  */
862 XXH_PUBLIC_API XXH_errorcode XXH3_64bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize);
863 
864 XXH_PUBLIC_API XXH_errorcode XXH3_64bits_update (XXH3_state_t* statePtr, const void* input, size_t length);
865 XXH_PUBLIC_API XXH64_hash_t  XXH3_64bits_digest (const XXH3_state_t* statePtr);
866 
867 /* note : canonical representation of XXH3 is the same as XXH64
868  * since they both produce XXH64_hash_t values */
869 
870 
871 /*-**********************************************************************
872 *  XXH3 128-bit variant
873 ************************************************************************/
874 
875 /*!
876  * @brief The return value from 128-bit hashes.
877  *
878  * Stored in little endian order, although the fields themselves are in native
879  * endianness.
880  */
881 typedef struct {
882     XXH64_hash_t low64;   /*!< `value & 0xFFFFFFFFFFFFFFFF` */
883     XXH64_hash_t high64;  /*!< `value >> 64` */
884 } XXH128_hash_t;
885 
886 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits(const void* data, size_t len);
887 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_withSeed(const void* data, size_t len, XXH64_hash_t seed);
888 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_withSecret(const void* data, size_t len, const void* secret, size_t secretSize);
889 
890 /*******   Streaming   *******/
891 /*
892  * Streaming requires state maintenance.
893  * This operation costs memory and CPU.
894  * As a consequence, streaming is slower than one-shot hashing.
895  * For better performance, prefer one-shot functions whenever applicable.
896  *
897  * XXH3_128bits uses the same XXH3_state_t as XXH3_64bits().
898  * Use already declared XXH3_createState() and XXH3_freeState().
899  *
900  * All reset and streaming functions have same meaning as their 64-bit counterpart.
901  */
902 
903 XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset(XXH3_state_t* statePtr);
904 XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed);
905 XXH_PUBLIC_API XXH_errorcode XXH3_128bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize);
906 
907 XXH_PUBLIC_API XXH_errorcode XXH3_128bits_update (XXH3_state_t* statePtr, const void* input, size_t length);
908 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_digest (const XXH3_state_t* statePtr);
909 
910 /* Following helper functions make it possible to compare XXH128_hast_t values.
911  * Since XXH128_hash_t is a structure, this capability is not offered by the language.
912  * Note: For better performance, these functions can be inlined using XXH_INLINE_ALL */
913 
914 /*!
915  * XXH128_isEqual():
916  * Return: 1 if `h1` and `h2` are equal, 0 if they are not.
917  */
918 XXH_PUBLIC_API int XXH128_isEqual(XXH128_hash_t h1, XXH128_hash_t h2);
919 
920 /*!
921  * XXH128_cmp():
922  *
923  * This comparator is compatible with stdlib's `qsort()`/`bsearch()`.
924  *
925  * return: >0 if *h128_1  > *h128_2
926  *         =0 if *h128_1 == *h128_2
927  *         <0 if *h128_1  < *h128_2
928  */
929 XXH_PUBLIC_API int XXH128_cmp(const void* h128_1, const void* h128_2);
930 
931 
932 /*******   Canonical representation   *******/
933 typedef struct { unsigned char digest[sizeof(XXH128_hash_t)]; } XXH128_canonical_t;
934 XXH_PUBLIC_API void XXH128_canonicalFromHash(XXH128_canonical_t* dst, XXH128_hash_t hash);
935 XXH_PUBLIC_API XXH128_hash_t XXH128_hashFromCanonical(const XXH128_canonical_t* src);
936 
937 
938 #endif  /* XXH_NO_LONG_LONG */
939 
940 /*!
941  * @}
942  */
943 #endif /* XXHASH_H_5627135585666179 */
944 
945 
946 
947 #if defined(XXH_STATIC_LINKING_ONLY) && !defined(XXHASH_H_STATIC_13879238742)
948 #define XXHASH_H_STATIC_13879238742
949 /* ****************************************************************************
950  * This section contains declarations which are not guaranteed to remain stable.
951  * They may change in future versions, becoming incompatible with a different
952  * version of the library.
953  * These declarations should only be used with static linking.
954  * Never use them in association with dynamic linking!
955  ***************************************************************************** */
956 
957 /*
958  * These definitions are only present to allow static allocation
959  * of XXH states, on stack or in a struct, for example.
960  * Never **ever** access their members directly.
961  */
962 
963 /*!
964  * @internal
965  * @brief Structure for XXH32 streaming API.
966  *
967  * @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
968  * @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined. Otherwise it is
969  * an opaque type. This allows fields to safely be changed.
970  *
971  * Typedef'd to @ref XXH32_state_t.
972  * Do not access the members of this struct directly.
973  * @see XXH64_state_s, XXH3_state_s
974  */
975 struct XXH32_state_s {
976    XXH32_hash_t total_len_32; /*!< Total length hashed, modulo 2^32 */
977    XXH32_hash_t large_len;    /*!< Whether the hash is >= 16 (handles @ref total_len_32 overflow) */
978    XXH32_hash_t v[4];         /*!< Accumulator lanes */
979    XXH32_hash_t mem32[4];     /*!< Internal buffer for partial reads. Treated as unsigned char[16]. */
980    XXH32_hash_t memsize;      /*!< Amount of data in @ref mem32 */
981    XXH32_hash_t reserved;     /*!< Reserved field. Do not read or write to it, it may be removed. */
982 };   /* typedef'd to XXH32_state_t */
983 
984 
985 #ifndef XXH_NO_LONG_LONG  /* defined when there is no 64-bit support */
986 
987 /*!
988  * @internal
989  * @brief Structure for XXH64 streaming API.
990  *
991  * @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
992  * @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined. Otherwise it is
993  * an opaque type. This allows fields to safely be changed.
994  *
995  * Typedef'd to @ref XXH64_state_t.
996  * Do not access the members of this struct directly.
997  * @see XXH32_state_s, XXH3_state_s
998  */
999 struct XXH64_state_s {
1000    XXH64_hash_t total_len;    /*!< Total length hashed. This is always 64-bit. */
1001    XXH64_hash_t v[4];         /*!< Accumulator lanes */
1002    XXH64_hash_t mem64[4];     /*!< Internal buffer for partial reads. Treated as unsigned char[32]. */
1003    XXH32_hash_t memsize;      /*!< Amount of data in @ref mem64 */
1004    XXH32_hash_t reserved32;   /*!< Reserved field, needed for padding anyways*/
1005    XXH64_hash_t reserved64;   /*!< Reserved field. Do not read or write to it, it may be removed. */
1006 };   /* typedef'd to XXH64_state_t */
1007 
1008 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) /* >= C11 */
1009 #  include <stdalign.h>
1010 #  define XXH_ALIGN(n)      alignas(n)
1011 #elif defined(__cplusplus) && (__cplusplus >= 201103L) /* >= C++11 */
1012 /* In C++ alignas() is a keyword */
1013 #  define XXH_ALIGN(n)      alignas(n)
1014 #elif defined(__GNUC__)
1015 #  define XXH_ALIGN(n)      __attribute__ ((aligned(n)))
1016 #elif defined(_MSC_VER)
1017 #  define XXH_ALIGN(n)      __declspec(align(n))
1018 #else
1019 #  define XXH_ALIGN(n)   /* disabled */
1020 #endif
1021 
1022 /* Old GCC versions only accept the attribute after the type in structures. */
1023 #if !(defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L))   /* C11+ */ \
1024     && ! (defined(__cplusplus) && (__cplusplus >= 201103L)) /* >= C++11 */ \
1025     && defined(__GNUC__)
1026 #   define XXH_ALIGN_MEMBER(align, type) type XXH_ALIGN(align)
1027 #else
1028 #   define XXH_ALIGN_MEMBER(align, type) XXH_ALIGN(align) type
1029 #endif
1030 
1031 /*!
1032  * @brief The size of the internal XXH3 buffer.
1033  *
1034  * This is the optimal update size for incremental hashing.
1035  *
1036  * @see XXH3_64b_update(), XXH3_128b_update().
1037  */
1038 #define XXH3_INTERNALBUFFER_SIZE 256
1039 
1040 /*!
1041  * @brief Default size of the secret buffer (and @ref XXH3_kSecret).
1042  *
1043  * This is the size used in @ref XXH3_kSecret and the seeded functions.
1044  *
1045  * Not to be confused with @ref XXH3_SECRET_SIZE_MIN.
1046  */
1047 #define XXH3_SECRET_DEFAULT_SIZE 192
1048 
1049 /*!
1050  * @internal
1051  * @brief Structure for XXH3 streaming API.
1052  *
1053  * @note This is only defined when @ref XXH_STATIC_LINKING_ONLY,
1054  * @ref XXH_INLINE_ALL, or @ref XXH_IMPLEMENTATION is defined.
1055  * Otherwise it is an opaque type.
1056  * Never use this definition in combination with dynamic library.
1057  * This allows fields to safely be changed in the future.
1058  *
1059  * @note ** This structure has a strict alignment requirement of 64 bytes!! **
1060  * Do not allocate this with `malloc()` or `new`,
1061  * it will not be sufficiently aligned.
1062  * Use @ref XXH3_createState() and @ref XXH3_freeState(), or stack allocation.
1063  *
1064  * Typedef'd to @ref XXH3_state_t.
1065  * Do never access the members of this struct directly.
1066  *
1067  * @see XXH3_INITSTATE() for stack initialization.
1068  * @see XXH3_createState(), XXH3_freeState().
1069  * @see XXH32_state_s, XXH64_state_s
1070  */
1071 struct XXH3_state_s {
1072    XXH_ALIGN_MEMBER(64, XXH64_hash_t acc[8]);
1073        /*!< The 8 accumulators. Similar to `vN` in @ref XXH32_state_s::v1 and @ref XXH64_state_s */
1074    XXH_ALIGN_MEMBER(64, unsigned char customSecret[XXH3_SECRET_DEFAULT_SIZE]);
1075        /*!< Used to store a custom secret generated from a seed. */
1076    XXH_ALIGN_MEMBER(64, unsigned char buffer[XXH3_INTERNALBUFFER_SIZE]);
1077        /*!< The internal buffer. @see XXH32_state_s::mem32 */
1078    XXH32_hash_t bufferedSize;
1079        /*!< The amount of memory in @ref buffer, @see XXH32_state_s::memsize */
1080    XXH32_hash_t useSeed;
1081        /*!< Reserved field. Needed for padding on 64-bit. */
1082    size_t nbStripesSoFar;
1083        /*!< Number or stripes processed. */
1084    XXH64_hash_t totalLen;
1085        /*!< Total length hashed. 64-bit even on 32-bit targets. */
1086    size_t nbStripesPerBlock;
1087        /*!< Number of stripes per block. */
1088    size_t secretLimit;
1089        /*!< Size of @ref customSecret or @ref extSecret */
1090    XXH64_hash_t seed;
1091        /*!< Seed for _withSeed variants. Must be zero otherwise, @see XXH3_INITSTATE() */
1092    XXH64_hash_t reserved64;
1093        /*!< Reserved field. */
1094    const unsigned char* extSecret;
1095        /*!< Reference to an external secret for the _withSecret variants, NULL
1096         *   for other variants. */
1097    /* note: there may be some padding at the end due to alignment on 64 bytes */
1098 }; /* typedef'd to XXH3_state_t */
1099 
1100 #undef XXH_ALIGN_MEMBER
1101 
1102 /*!
1103  * @brief Initializes a stack-allocated `XXH3_state_s`.
1104  *
1105  * When the @ref XXH3_state_t structure is merely emplaced on stack,
1106  * it should be initialized with XXH3_INITSTATE() or a memset()
1107  * in case its first reset uses XXH3_NNbits_reset_withSeed().
1108  * This init can be omitted if the first reset uses default or _withSecret mode.
1109  * This operation isn't necessary when the state is created with XXH3_createState().
1110  * Note that this doesn't prepare the state for a streaming operation,
1111  * it's still necessary to use XXH3_NNbits_reset*() afterwards.
1112  */
1113 #define XXH3_INITSTATE(XXH3_state_ptr)   { (XXH3_state_ptr)->seed = 0; }
1114 
1115 
1116 /* XXH128() :
1117  * simple alias to pre-selected XXH3_128bits variant
1118  */
1119 XXH_PUBLIC_API XXH128_hash_t XXH128(const void* data, size_t len, XXH64_hash_t seed);
1120 
1121 
1122 /* ===   Experimental API   === */
1123 /* Symbols defined below must be considered tied to a specific library version. */
1124 
1125 /*
1126  * XXH3_generateSecret():
1127  *
1128  * Derive a high-entropy secret from any user-defined content, named customSeed.
1129  * The generated secret can be used in combination with `*_withSecret()` functions.
1130  * The `_withSecret()` variants are useful to provide a higher level of protection than 64-bit seed,
1131  * as it becomes much more difficult for an external actor to guess how to impact the calculation logic.
1132  *
1133  * The function accepts as input a custom seed of any length and any content,
1134  * and derives from it a high-entropy secret of length @secretSize
1135  * into an already allocated buffer @secretBuffer.
1136  * @secretSize must be >= XXH3_SECRET_SIZE_MIN
1137  *
1138  * The generated secret can then be used with any `*_withSecret()` variant.
1139  * Functions `XXH3_128bits_withSecret()`, `XXH3_64bits_withSecret()`,
1140  * `XXH3_128bits_reset_withSecret()` and `XXH3_64bits_reset_withSecret()`
1141  * are part of this list. They all accept a `secret` parameter
1142  * which must be large enough for implementation reasons (>= XXH3_SECRET_SIZE_MIN)
1143  * _and_ feature very high entropy (consist of random-looking bytes).
1144  * These conditions can be a high bar to meet, so
1145  * XXH3_generateSecret() can be employed to ensure proper quality.
1146  *
1147  * customSeed can be anything. It can have any size, even small ones,
1148  * and its content can be anything, even "poor entropy" sources such as a bunch of zeroes.
1149  * The resulting `secret` will nonetheless provide all required qualities.
1150  *
1151  * When customSeedSize > 0, supplying NULL as customSeed is undefined behavior.
1152  */
1153 XXH_PUBLIC_API XXH_errorcode XXH3_generateSecret(void* secretBuffer, size_t secretSize, const void* customSeed, size_t customSeedSize);
1154 
1155 
1156 /*
1157  * XXH3_generateSecret_fromSeed():
1158  *
1159  * Generate the same secret as the _withSeed() variants.
1160  *
1161  * The resulting secret has a length of XXH3_SECRET_DEFAULT_SIZE (necessarily).
1162  * @secretBuffer must be already allocated, of size at least XXH3_SECRET_DEFAULT_SIZE bytes.
1163  *
1164  * The generated secret can be used in combination with
1165  *`*_withSecret()` and `_withSecretandSeed()` variants.
1166  * This generator is notably useful in combination with `_withSecretandSeed()`,
1167  * as a way to emulate a faster `_withSeed()` variant.
1168  */
1169 XXH_PUBLIC_API void XXH3_generateSecret_fromSeed(void* secretBuffer, XXH64_hash_t seed);
1170 
1171 /*
1172  * *_withSecretandSeed() :
1173  * These variants generate hash values using either
1174  * @seed for "short" keys (< XXH3_MIDSIZE_MAX = 240 bytes)
1175  * or @secret for "large" keys (>= XXH3_MIDSIZE_MAX).
1176  *
1177  * This generally benefits speed, compared to `_withSeed()` or `_withSecret()`.
1178  * `_withSeed()` has to generate the secret on the fly for "large" keys.
1179  * It's fast, but can be perceptible for "not so large" keys (< 1 KB).
1180  * `_withSecret()` has to generate the masks on the fly for "small" keys,
1181  * which requires more instructions than _withSeed() variants.
1182  * Therefore, _withSecretandSeed variant combines the best of both worlds.
1183  *
1184  * When @secret has been generated by XXH3_generateSecret_fromSeed(),
1185  * this variant produces *exactly* the same results as `_withSeed()` variant,
1186  * hence offering only a pure speed benefit on "large" input,
1187  * by skipping the need to regenerate the secret for every large input.
1188  *
1189  * Another usage scenario is to hash the secret to a 64-bit hash value,
1190  * for example with XXH3_64bits(), which then becomes the seed,
1191  * and then employ both the seed and the secret in _withSecretandSeed().
1192  * On top of speed, an added benefit is that each bit in the secret
1193  * has a 50% chance to swap each bit in the output,
1194  * via its impact to the seed.
1195  * This is not guaranteed when using the secret directly in "small data" scenarios,
1196  * because only portions of the secret are employed for small data.
1197  */
1198 XXH_PUBLIC_API XXH64_hash_t
1199 XXH3_64bits_withSecretandSeed(const void* data, size_t len,
1200                               const void* secret, size_t secretSize,
1201                               XXH64_hash_t seed);
1202 
1203 XXH_PUBLIC_API XXH128_hash_t
1204 XXH3_128bits_withSecretandSeed(const void* data, size_t len,
1205                                const void* secret, size_t secretSize,
1206                                XXH64_hash_t seed64);
1207 
1208 XXH_PUBLIC_API XXH_errorcode
1209 XXH3_64bits_reset_withSecretandSeed(XXH3_state_t* statePtr,
1210                                     const void* secret, size_t secretSize,
1211                                     XXH64_hash_t seed64);
1212 
1213 XXH_PUBLIC_API XXH_errorcode
1214 XXH3_128bits_reset_withSecretandSeed(XXH3_state_t* statePtr,
1215                                      const void* secret, size_t secretSize,
1216                                      XXH64_hash_t seed64);
1217 
1218 
1219 #endif  /* XXH_NO_LONG_LONG */
1220 #if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)
1221 #  define XXH_IMPLEMENTATION
1222 #endif
1223 
1224 #endif  /* defined(XXH_STATIC_LINKING_ONLY) && !defined(XXHASH_H_STATIC_13879238742) */
1225 
1226 
1227 /* ======================================================================== */
1228 /* ======================================================================== */
1229 /* ======================================================================== */
1230 
1231 
1232 /*-**********************************************************************
1233  * xxHash implementation
1234  *-**********************************************************************
1235  * xxHash's implementation used to be hosted inside xxhash.c.
1236  *
1237  * However, inlining requires implementation to be visible to the compiler,
1238  * hence be included alongside the header.
1239  * Previously, implementation was hosted inside xxhash.c,
1240  * which was then #included when inlining was activated.
1241  * This construction created issues with a few build and install systems,
1242  * as it required xxhash.c to be stored in /include directory.
1243  *
1244  * xxHash implementation is now directly integrated within xxhash.h.
1245  * As a consequence, xxhash.c is no longer needed in /include.
1246  *
1247  * xxhash.c is still available and is still useful.
1248  * In a "normal" setup, when xxhash is not inlined,
1249  * xxhash.h only exposes the prototypes and public symbols,
1250  * while xxhash.c can be built into an object file xxhash.o
1251  * which can then be linked into the final binary.
1252  ************************************************************************/
1253 
1254 #if ( defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API) \
1255    || defined(XXH_IMPLEMENTATION) ) && !defined(XXH_IMPLEM_13a8737387)
1256 #  define XXH_IMPLEM_13a8737387
1257 
1258 /* *************************************
1259 *  Tuning parameters
1260 ***************************************/
1261 
1262 /*!
1263  * @defgroup tuning Tuning parameters
1264  * @{
1265  *
1266  * Various macros to control xxHash's behavior.
1267  */
1268 #ifdef XXH_DOXYGEN
1269 /*!
1270  * @brief Define this to disable 64-bit code.
1271  *
1272  * Useful if only using the @ref xxh32_family and you have a strict C90 compiler.
1273  */
1274 #  define XXH_NO_LONG_LONG
1275 #  undef XXH_NO_LONG_LONG /* don't actually */
1276 /*!
1277  * @brief Controls how unaligned memory is accessed.
1278  *
1279  * By default, access to unaligned memory is controlled by `memcpy()`, which is
1280  * safe and portable.
1281  *
1282  * Unfortunately, on some target/compiler combinations, the generated assembly
1283  * is sub-optimal.
1284  *
1285  * The below switch allow selection of a different access method
1286  * in the search for improved performance.
1287  *
1288  * @par Possible options:
1289  *
1290  *  - `XXH_FORCE_MEMORY_ACCESS=0` (default): `memcpy`
1291  *   @par
1292  *     Use `memcpy()`. Safe and portable. Note that most modern compilers will
1293  *     eliminate the function call and treat it as an unaligned access.
1294  *
1295  *  - `XXH_FORCE_MEMORY_ACCESS=1`: `__attribute__((packed))`
1296  *   @par
1297  *     Depends on compiler extensions and is therefore not portable.
1298  *     This method is safe _if_ your compiler supports it,
1299  *     and *generally* as fast or faster than `memcpy`.
1300  *
1301  *  - `XXH_FORCE_MEMORY_ACCESS=2`: Direct cast
1302  *  @par
1303  *     Casts directly and dereferences. This method doesn't depend on the
1304  *     compiler, but it violates the C standard as it directly dereferences an
1305  *     unaligned pointer. It can generate buggy code on targets which do not
1306  *     support unaligned memory accesses, but in some circumstances, it's the
1307  *     only known way to get the most performance.
1308  *
1309  *  - `XXH_FORCE_MEMORY_ACCESS=3`: Byteshift
1310  *  @par
1311  *     Also portable. This can generate the best code on old compilers which don't
1312  *     inline small `memcpy()` calls, and it might also be faster on big-endian
1313  *     systems which lack a native byteswap instruction. However, some compilers
1314  *     will emit literal byteshifts even if the target supports unaligned access.
1315  *  .
1316  *
1317  * @warning
1318  *   Methods 1 and 2 rely on implementation-defined behavior. Use these with
1319  *   care, as what works on one compiler/platform/optimization level may cause
1320  *   another to read garbage data or even crash.
1321  *
1322  * See http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html for details.
1323  *
1324  * Prefer these methods in priority order (0 > 3 > 1 > 2)
1325  */
1326 #  define XXH_FORCE_MEMORY_ACCESS 0
1327 
1328 /*!
1329  * @def XXH_FORCE_ALIGN_CHECK
1330  * @brief If defined to non-zero, adds a special path for aligned inputs (XXH32()
1331  * and XXH64() only).
1332  *
1333  * This is an important performance trick for architectures without decent
1334  * unaligned memory access performance.
1335  *
1336  * It checks for input alignment, and when conditions are met, uses a "fast
1337  * path" employing direct 32-bit/64-bit reads, resulting in _dramatically
1338  * faster_ read speed.
1339  *
1340  * The check costs one initial branch per hash, which is generally negligible,
1341  * but not zero.
1342  *
1343  * Moreover, it's not useful to generate an additional code path if memory
1344  * access uses the same instruction for both aligned and unaligned
1345  * addresses (e.g. x86 and aarch64).
1346  *
1347  * In these cases, the alignment check can be removed by setting this macro to 0.
1348  * Then the code will always use unaligned memory access.
1349  * Align check is automatically disabled on x86, x64 & arm64,
1350  * which are platforms known to offer good unaligned memory accesses performance.
1351  *
1352  * This option does not affect XXH3 (only XXH32 and XXH64).
1353  */
1354 #  define XXH_FORCE_ALIGN_CHECK 0
1355 
1356 /*!
1357  * @def XXH_NO_INLINE_HINTS
1358  * @brief When non-zero, sets all functions to `static`.
1359  *
1360  * By default, xxHash tries to force the compiler to inline almost all internal
1361  * functions.
1362  *
1363  * This can usually improve performance due to reduced jumping and improved
1364  * constant folding, but significantly increases the size of the binary which
1365  * might not be favorable.
1366  *
1367  * Additionally, sometimes the forced inlining can be detrimental to performance,
1368  * depending on the architecture.
1369  *
1370  * XXH_NO_INLINE_HINTS marks all internal functions as static, giving the
1371  * compiler full control on whether to inline or not.
1372  *
1373  * When not optimizing (-O0), optimizing for size (-Os, -Oz), or using
1374  * -fno-inline with GCC or Clang, this will automatically be defined.
1375  */
1376 #  define XXH_NO_INLINE_HINTS 0
1377 
1378 /*!
1379  * @def XXH32_ENDJMP
1380  * @brief Whether to use a jump for `XXH32_finalize`.
1381  *
1382  * For performance, `XXH32_finalize` uses multiple branches in the finalizer.
1383  * This is generally preferable for performance,
1384  * but depending on exact architecture, a jmp may be preferable.
1385  *
1386  * This setting is only possibly making a difference for very small inputs.
1387  */
1388 #  define XXH32_ENDJMP 0
1389 
1390 /*!
1391  * @internal
1392  * @brief Redefines old internal names.
1393  *
1394  * For compatibility with code that uses xxHash's internals before the names
1395  * were changed to improve namespacing. There is no other reason to use this.
1396  */
1397 #  define XXH_OLD_NAMES
1398 #  undef XXH_OLD_NAMES /* don't actually use, it is ugly. */
1399 #endif /* XXH_DOXYGEN */
1400 /*!
1401  * @}
1402  */
1403 
1404 #ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
1405    /* prefer __packed__ structures (method 1) for gcc on armv7+ and mips */
1406 #  if !defined(__clang__) && \
1407 ( \
1408     (defined(__INTEL_COMPILER) && !defined(_WIN32)) || \
1409     ( \
1410         defined(__GNUC__) && ( \
1411             (defined(__ARM_ARCH) && __ARM_ARCH >= 7) || \
1412             ( \
1413                 defined(__mips__) && \
1414                 (__mips <= 5 || __mips_isa_rev < 6) && \
1415                 (!defined(__mips16) || defined(__mips_mips16e2)) \
1416             ) \
1417         ) \
1418     ) \
1419 )
1420 #    define XXH_FORCE_MEMORY_ACCESS 1
1421 #  endif
1422 #endif
1423 
1424 #ifndef XXH_FORCE_ALIGN_CHECK  /* can be defined externally */
1425 #  if defined(__i386)  || defined(__x86_64__) || defined(__aarch64__) \
1426    || defined(_M_IX86) || defined(_M_X64)     || defined(_M_ARM64) /* visual */
1427 #    define XXH_FORCE_ALIGN_CHECK 0
1428 #  else
1429 #    define XXH_FORCE_ALIGN_CHECK 1
1430 #  endif
1431 #endif
1432 
1433 #ifndef XXH_NO_INLINE_HINTS
1434 #  if defined(__OPTIMIZE_SIZE__) /* -Os, -Oz */ \
1435    || defined(__NO_INLINE__)     /* -O0, -fno-inline */
1436 #    define XXH_NO_INLINE_HINTS 1
1437 #  else
1438 #    define XXH_NO_INLINE_HINTS 0
1439 #  endif
1440 #endif
1441 
1442 #ifndef XXH32_ENDJMP
1443 /* generally preferable for performance */
1444 #  define XXH32_ENDJMP 0
1445 #endif
1446 
1447 /*!
1448  * @defgroup impl Implementation
1449  * @{
1450  */
1451 
1452 
1453 /* *************************************
1454 *  Includes & Memory related functions
1455 ***************************************/
1456 /*
1457  * Modify the local functions below should you wish to use
1458  * different memory routines for malloc() and free()
1459  */
1460 #include <stdlib.h>
1461 
1462 /*!
1463  * @internal
1464  * @brief Modify this function to use a different routine than malloc().
1465  */
XXH_malloc(size_t s)1466 static void* XXH_malloc(size_t s) { return malloc(s); }
1467 
1468 /*!
1469  * @internal
1470  * @brief Modify this function to use a different routine than free().
1471  */
XXH_free(void * p)1472 static void XXH_free(void* p) { free(p); }
1473 
1474 #include <string.h>
1475 
1476 /*!
1477  * @internal
1478  * @brief Modify this function to use a different routine than memcpy().
1479  */
XXH_memcpy(void * dest,const void * src,size_t size)1480 static void* XXH_memcpy(void* dest, const void* src, size_t size)
1481 {
1482     return memcpy(dest,src,size);
1483 }
1484 
1485 #include <limits.h>   /* ULLONG_MAX */
1486 
1487 
1488 /* *************************************
1489 *  Compiler Specific Options
1490 ***************************************/
1491 #ifdef _MSC_VER /* Visual Studio warning fix */
1492 #  pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
1493 #endif
1494 
1495 #if XXH_NO_INLINE_HINTS  /* disable inlining hints */
1496 #  if defined(__GNUC__) || defined(__clang__)
1497 #    define XXH_FORCE_INLINE static __attribute__((unused))
1498 #  else
1499 #    define XXH_FORCE_INLINE static
1500 #  endif
1501 #  define XXH_NO_INLINE static
1502 /* enable inlining hints */
1503 #elif defined(__GNUC__) || defined(__clang__)
1504 #  define XXH_FORCE_INLINE static __inline__ __attribute__((always_inline, unused))
1505 #  define XXH_NO_INLINE static __attribute__((noinline))
1506 #elif defined(_MSC_VER)  /* Visual Studio */
1507 #  define XXH_FORCE_INLINE static __forceinline
1508 #  define XXH_NO_INLINE static __declspec(noinline)
1509 #elif defined (__cplusplus) \
1510   || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L))   /* C99 */
1511 #  define XXH_FORCE_INLINE static inline
1512 #  define XXH_NO_INLINE static
1513 #else
1514 #  define XXH_FORCE_INLINE static
1515 #  define XXH_NO_INLINE static
1516 #endif
1517 
1518 
1519 
1520 /* *************************************
1521 *  Debug
1522 ***************************************/
1523 /*!
1524  * @ingroup tuning
1525  * @def XXH_DEBUGLEVEL
1526  * @brief Sets the debugging level.
1527  *
1528  * XXH_DEBUGLEVEL is expected to be defined externally, typically via the
1529  * compiler's command line options. The value must be a number.
1530  */
1531 #ifndef XXH_DEBUGLEVEL
1532 #  ifdef DEBUGLEVEL /* backwards compat */
1533 #    define XXH_DEBUGLEVEL DEBUGLEVEL
1534 #  else
1535 #    define XXH_DEBUGLEVEL 0
1536 #  endif
1537 #endif
1538 
1539 #if (XXH_DEBUGLEVEL>=1)
1540 #  include <assert.h>   /* note: can still be disabled with NDEBUG */
1541 #  define XXH_ASSERT(c)   assert(c)
1542 #else
1543 #  define XXH_ASSERT(c)   ((void)0)
1544 #endif
1545 
1546 /* note: use after variable declarations */
1547 #ifndef XXH_STATIC_ASSERT
1548 #  if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)    /* C11 */
1549 #    define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { _Static_assert((c),m); } while(0)
1550 #  elif defined(__cplusplus) && (__cplusplus >= 201103L)            /* C++11 */
1551 #    define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { static_assert((c),m); } while(0)
1552 #  else
1553 #    define XXH_STATIC_ASSERT_WITH_MESSAGE(c,m) do { struct xxh_sa { char x[(c) ? 1 : -1]; }; } while(0)
1554 #  endif
1555 #  define XXH_STATIC_ASSERT(c) XXH_STATIC_ASSERT_WITH_MESSAGE((c),#c)
1556 #endif
1557 
1558 /*!
1559  * @internal
1560  * @def XXH_COMPILER_GUARD(var)
1561  * @brief Used to prevent unwanted optimizations for @p var.
1562  *
1563  * It uses an empty GCC inline assembly statement with a register constraint
1564  * which forces @p var into a general purpose register (eg eax, ebx, ecx
1565  * on x86) and marks it as modified.
1566  *
1567  * This is used in a few places to avoid unwanted autovectorization (e.g.
1568  * XXH32_round()). All vectorization we want is explicit via intrinsics,
1569  * and _usually_ isn't wanted elsewhere.
1570  *
1571  * We also use it to prevent unwanted constant folding for AArch64 in
1572  * XXH3_initCustomSecret_scalar().
1573  */
1574 #if defined(__GNUC__) || defined(__clang__)
1575 #  define XXH_COMPILER_GUARD(var) __asm__ __volatile__("" : "+r" (var))
1576 #else
1577 #  define XXH_COMPILER_GUARD(var) ((void)0)
1578 #endif
1579 
1580 /* *************************************
1581 *  Basic Types
1582 ***************************************/
1583 #if !defined (__VMS) \
1584  && (defined (__cplusplus) \
1585  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
1586 # include <stdint.h>
1587   typedef uint8_t xxh_u8;
1588 #else
1589   typedef unsigned char xxh_u8;
1590 #endif
1591 typedef XXH32_hash_t xxh_u32;
1592 
1593 #ifdef XXH_OLD_NAMES
1594 #  define BYTE xxh_u8
1595 #  define U8   xxh_u8
1596 #  define U32  xxh_u32
1597 #endif
1598 
1599 /* ***   Memory access   *** */
1600 
1601 /*!
1602  * @internal
1603  * @fn xxh_u32 XXH_read32(const void* ptr)
1604  * @brief Reads an unaligned 32-bit integer from @p ptr in native endianness.
1605  *
1606  * Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1607  *
1608  * @param ptr The pointer to read from.
1609  * @return The 32-bit native endian integer from the bytes at @p ptr.
1610  */
1611 
1612 /*!
1613  * @internal
1614  * @fn xxh_u32 XXH_readLE32(const void* ptr)
1615  * @brief Reads an unaligned 32-bit little endian integer from @p ptr.
1616  *
1617  * Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1618  *
1619  * @param ptr The pointer to read from.
1620  * @return The 32-bit little endian integer from the bytes at @p ptr.
1621  */
1622 
1623 /*!
1624  * @internal
1625  * @fn xxh_u32 XXH_readBE32(const void* ptr)
1626  * @brief Reads an unaligned 32-bit big endian integer from @p ptr.
1627  *
1628  * Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1629  *
1630  * @param ptr The pointer to read from.
1631  * @return The 32-bit big endian integer from the bytes at @p ptr.
1632  */
1633 
1634 /*!
1635  * @internal
1636  * @fn xxh_u32 XXH_readLE32_align(const void* ptr, XXH_alignment align)
1637  * @brief Like @ref XXH_readLE32(), but has an option for aligned reads.
1638  *
1639  * Affected by @ref XXH_FORCE_MEMORY_ACCESS.
1640  * Note that when @ref XXH_FORCE_ALIGN_CHECK == 0, the @p align parameter is
1641  * always @ref XXH_alignment::XXH_unaligned.
1642  *
1643  * @param ptr The pointer to read from.
1644  * @param align Whether @p ptr is aligned.
1645  * @pre
1646  *   If @p align == @ref XXH_alignment::XXH_aligned, @p ptr must be 4 byte
1647  *   aligned.
1648  * @return The 32-bit little endian integer from the bytes at @p ptr.
1649  */
1650 
1651 #if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
1652 /*
1653  * Manual byteshift. Best for old compilers which don't inline memcpy.
1654  * We actually directly use XXH_readLE32 and XXH_readBE32.
1655  */
1656 #elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
1657 
1658 /*
1659  * Force direct memory access. Only works on CPU which support unaligned memory
1660  * access in hardware.
1661  */
XXH_read32(const void * memPtr)1662 static xxh_u32 XXH_read32(const void* memPtr) { return *(const xxh_u32*) memPtr; }
1663 
1664 #elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
1665 
1666 /*
1667  * __pack instructions are safer but compiler specific, hence potentially
1668  * problematic for some compilers.
1669  *
1670  * Currently only defined for GCC and ICC.
1671  */
1672 #ifdef XXH_OLD_NAMES
1673 typedef union { xxh_u32 u32; } __attribute__((packed)) unalign;
1674 #endif
XXH_read32(const void * ptr)1675 static xxh_u32 XXH_read32(const void* ptr)
1676 {
1677     typedef union { xxh_u32 u32; } __attribute__((packed)) xxh_unalign;
1678     return ((const xxh_unalign*)ptr)->u32;
1679 }
1680 
1681 #else
1682 
1683 /*
1684  * Portable and safe solution. Generally efficient.
1685  * see: http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html
1686  */
XXH_read32(const void * memPtr)1687 static xxh_u32 XXH_read32(const void* memPtr)
1688 {
1689     xxh_u32 val;
1690     XXH_memcpy(&val, memPtr, sizeof(val));
1691     return val;
1692 }
1693 
1694 #endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
1695 
1696 
1697 /* ***   Endianness   *** */
1698 
1699 /*!
1700  * @ingroup tuning
1701  * @def XXH_CPU_LITTLE_ENDIAN
1702  * @brief Whether the target is little endian.
1703  *
1704  * Defined to 1 if the target is little endian, or 0 if it is big endian.
1705  * It can be defined externally, for example on the compiler command line.
1706  *
1707  * If it is not defined,
1708  * a runtime check (which is usually constant folded) is used instead.
1709  *
1710  * @note
1711  *   This is not necessarily defined to an integer constant.
1712  *
1713  * @see XXH_isLittleEndian() for the runtime check.
1714  */
1715 #ifndef XXH_CPU_LITTLE_ENDIAN
1716 /*
1717  * Try to detect endianness automatically, to avoid the nonstandard behavior
1718  * in `XXH_isLittleEndian()`
1719  */
1720 #  if defined(_WIN32) /* Windows is always little endian */ \
1721      || defined(__LITTLE_ENDIAN__) \
1722      || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
1723 #    define XXH_CPU_LITTLE_ENDIAN 1
1724 #  elif defined(__BIG_ENDIAN__) \
1725      || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
1726 #    define XXH_CPU_LITTLE_ENDIAN 0
1727 #  else
1728 /*!
1729  * @internal
1730  * @brief Runtime check for @ref XXH_CPU_LITTLE_ENDIAN.
1731  *
1732  * Most compilers will constant fold this.
1733  */
XXH_isLittleEndian(void)1734 static int XXH_isLittleEndian(void)
1735 {
1736     /*
1737      * Portable and well-defined behavior.
1738      * Don't use static: it is detrimental to performance.
1739      */
1740     const union { xxh_u32 u; xxh_u8 c[4]; } one = { 1 };
1741     return one.c[0];
1742 }
1743 #   define XXH_CPU_LITTLE_ENDIAN   XXH_isLittleEndian()
1744 #  endif
1745 #endif
1746 
1747 
1748 
1749 
1750 /* ****************************************
1751 *  Compiler-specific Functions and Macros
1752 ******************************************/
1753 #define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
1754 
1755 #ifdef __has_builtin
1756 #  define XXH_HAS_BUILTIN(x) __has_builtin(x)
1757 #else
1758 #  define XXH_HAS_BUILTIN(x) 0
1759 #endif
1760 
1761 /*!
1762  * @internal
1763  * @def XXH_rotl32(x,r)
1764  * @brief 32-bit rotate left.
1765  *
1766  * @param x The 32-bit integer to be rotated.
1767  * @param r The number of bits to rotate.
1768  * @pre
1769  *   @p r > 0 && @p r < 32
1770  * @note
1771  *   @p x and @p r may be evaluated multiple times.
1772  * @return The rotated result.
1773  */
1774 #if !defined(NO_CLANG_BUILTIN) && XXH_HAS_BUILTIN(__builtin_rotateleft32) \
1775                                && XXH_HAS_BUILTIN(__builtin_rotateleft64)
1776 #  define XXH_rotl32 __builtin_rotateleft32
1777 #  define XXH_rotl64 __builtin_rotateleft64
1778 /* Note: although _rotl exists for minGW (GCC under windows), performance seems poor */
1779 #elif defined(_MSC_VER)
1780 #  define XXH_rotl32(x,r) _rotl(x,r)
1781 #  define XXH_rotl64(x,r) _rotl64(x,r)
1782 #else
1783 #  define XXH_rotl32(x,r) (((x) << (r)) | ((x) >> (32 - (r))))
1784 #  define XXH_rotl64(x,r) (((x) << (r)) | ((x) >> (64 - (r))))
1785 #endif
1786 
1787 /*!
1788  * @internal
1789  * @fn xxh_u32 XXH_swap32(xxh_u32 x)
1790  * @brief A 32-bit byteswap.
1791  *
1792  * @param x The 32-bit integer to byteswap.
1793  * @return @p x, byteswapped.
1794  */
1795 #if defined(_MSC_VER)     /* Visual Studio */
1796 #  define XXH_swap32 _byteswap_ulong
1797 #elif XXH_GCC_VERSION >= 403
1798 #  define XXH_swap32 __builtin_bswap32
1799 #else
XXH_swap32(xxh_u32 x)1800 static xxh_u32 XXH_swap32 (xxh_u32 x)
1801 {
1802     return  ((x << 24) & 0xff000000 ) |
1803             ((x <<  8) & 0x00ff0000 ) |
1804             ((x >>  8) & 0x0000ff00 ) |
1805             ((x >> 24) & 0x000000ff );
1806 }
1807 #endif
1808 
1809 
1810 /* ***************************
1811 *  Memory reads
1812 *****************************/
1813 
1814 /*!
1815  * @internal
1816  * @brief Enum to indicate whether a pointer is aligned.
1817  */
1818 typedef enum {
1819     XXH_aligned,  /*!< Aligned */
1820     XXH_unaligned /*!< Possibly unaligned */
1821 } XXH_alignment;
1822 
1823 /*
1824  * XXH_FORCE_MEMORY_ACCESS==3 is an endian-independent byteshift load.
1825  *
1826  * This is ideal for older compilers which don't inline memcpy.
1827  */
1828 #if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
1829 
XXH_readLE32(const void * memPtr)1830 XXH_FORCE_INLINE xxh_u32 XXH_readLE32(const void* memPtr)
1831 {
1832     const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
1833     return bytePtr[0]
1834          | ((xxh_u32)bytePtr[1] << 8)
1835          | ((xxh_u32)bytePtr[2] << 16)
1836          | ((xxh_u32)bytePtr[3] << 24);
1837 }
1838 
XXH_readBE32(const void * memPtr)1839 XXH_FORCE_INLINE xxh_u32 XXH_readBE32(const void* memPtr)
1840 {
1841     const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
1842     return bytePtr[3]
1843          | ((xxh_u32)bytePtr[2] << 8)
1844          | ((xxh_u32)bytePtr[1] << 16)
1845          | ((xxh_u32)bytePtr[0] << 24);
1846 }
1847 
1848 #else
XXH_readLE32(const void * ptr)1849 XXH_FORCE_INLINE xxh_u32 XXH_readLE32(const void* ptr)
1850 {
1851     return XXH_CPU_LITTLE_ENDIAN ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
1852 }
1853 
XXH_readBE32(const void * ptr)1854 static xxh_u32 XXH_readBE32(const void* ptr)
1855 {
1856     return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
1857 }
1858 #endif
1859 
1860 XXH_FORCE_INLINE xxh_u32
XXH_readLE32_align(const void * ptr,XXH_alignment align)1861 XXH_readLE32_align(const void* ptr, XXH_alignment align)
1862 {
1863     if (align==XXH_unaligned) {
1864         return XXH_readLE32(ptr);
1865     } else {
1866         return XXH_CPU_LITTLE_ENDIAN ? *(const xxh_u32*)ptr : XXH_swap32(*(const xxh_u32*)ptr);
1867     }
1868 }
1869 
1870 
1871 /* *************************************
1872 *  Misc
1873 ***************************************/
1874 /*! @ingroup public */
XXH_versionNumber(void)1875 XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
1876 
1877 
1878 /* *******************************************************************
1879 *  32-bit hash functions
1880 *********************************************************************/
1881 /*!
1882  * @}
1883  * @defgroup xxh32_impl XXH32 implementation
1884  * @ingroup impl
1885  * @{
1886  */
1887  /* #define instead of static const, to be used as initializers */
1888 #define XXH_PRIME32_1  0x9E3779B1U  /*!< 0b10011110001101110111100110110001 */
1889 #define XXH_PRIME32_2  0x85EBCA77U  /*!< 0b10000101111010111100101001110111 */
1890 #define XXH_PRIME32_3  0xC2B2AE3DU  /*!< 0b11000010101100101010111000111101 */
1891 #define XXH_PRIME32_4  0x27D4EB2FU  /*!< 0b00100111110101001110101100101111 */
1892 #define XXH_PRIME32_5  0x165667B1U  /*!< 0b00010110010101100110011110110001 */
1893 
1894 #ifdef XXH_OLD_NAMES
1895 #  define PRIME32_1 XXH_PRIME32_1
1896 #  define PRIME32_2 XXH_PRIME32_2
1897 #  define PRIME32_3 XXH_PRIME32_3
1898 #  define PRIME32_4 XXH_PRIME32_4
1899 #  define PRIME32_5 XXH_PRIME32_5
1900 #endif
1901 
1902 /*!
1903  * @internal
1904  * @brief Normal stripe processing routine.
1905  *
1906  * This shuffles the bits so that any bit from @p input impacts several bits in
1907  * @p acc.
1908  *
1909  * @param acc The accumulator lane.
1910  * @param input The stripe of input to mix.
1911  * @return The mixed accumulator lane.
1912  */
XXH32_round(xxh_u32 acc,xxh_u32 input)1913 static xxh_u32 XXH32_round(xxh_u32 acc, xxh_u32 input)
1914 {
1915     acc += input * XXH_PRIME32_2;
1916     acc  = XXH_rotl32(acc, 13);
1917     acc *= XXH_PRIME32_1;
1918 #if (defined(__SSE4_1__) || defined(__aarch64__)) && !defined(XXH_ENABLE_AUTOVECTORIZE)
1919     /*
1920      * UGLY HACK:
1921      * A compiler fence is the only thing that prevents GCC and Clang from
1922      * autovectorizing the XXH32 loop (pragmas and attributes don't work for some
1923      * reason) without globally disabling SSE4.1.
1924      *
1925      * The reason we want to avoid vectorization is because despite working on
1926      * 4 integers at a time, there are multiple factors slowing XXH32 down on
1927      * SSE4:
1928      * - There's a ridiculous amount of lag from pmulld (10 cycles of latency on
1929      *   newer chips!) making it slightly slower to multiply four integers at
1930      *   once compared to four integers independently. Even when pmulld was
1931      *   fastest, Sandy/Ivy Bridge, it is still not worth it to go into SSE
1932      *   just to multiply unless doing a long operation.
1933      *
1934      * - Four instructions are required to rotate,
1935      *      movqda tmp,  v // not required with VEX encoding
1936      *      pslld  tmp, 13 // tmp <<= 13
1937      *      psrld  v,   19 // x >>= 19
1938      *      por    v,  tmp // x |= tmp
1939      *   compared to one for scalar:
1940      *      roll   v, 13    // reliably fast across the board
1941      *      shldl  v, v, 13 // Sandy Bridge and later prefer this for some reason
1942      *
1943      * - Instruction level parallelism is actually more beneficial here because
1944      *   the SIMD actually serializes this operation: While v1 is rotating, v2
1945      *   can load data, while v3 can multiply. SSE forces them to operate
1946      *   together.
1947      *
1948      * This is also enabled on AArch64, as Clang autovectorizes it incorrectly
1949      * and it is pointless writing a NEON implementation that is basically the
1950      * same speed as scalar for XXH32.
1951      */
1952     XXH_COMPILER_GUARD(acc);
1953 #endif
1954     return acc;
1955 }
1956 
1957 /*!
1958  * @internal
1959  * @brief Mixes all bits to finalize the hash.
1960  *
1961  * The final mix ensures that all input bits have a chance to impact any bit in
1962  * the output digest, resulting in an unbiased distribution.
1963  *
1964  * @param h32 The hash to avalanche.
1965  * @return The avalanched hash.
1966  */
XXH32_avalanche(xxh_u32 h32)1967 static xxh_u32 XXH32_avalanche(xxh_u32 h32)
1968 {
1969     h32 ^= h32 >> 15;
1970     h32 *= XXH_PRIME32_2;
1971     h32 ^= h32 >> 13;
1972     h32 *= XXH_PRIME32_3;
1973     h32 ^= h32 >> 16;
1974     return(h32);
1975 }
1976 
1977 #define XXH_get32bits(p) XXH_readLE32_align(p, align)
1978 
1979 /*!
1980  * @internal
1981  * @brief Processes the last 0-15 bytes of @p ptr.
1982  *
1983  * There may be up to 15 bytes remaining to consume from the input.
1984  * This final stage will digest them to ensure that all input bytes are present
1985  * in the final mix.
1986  *
1987  * @param h32 The hash to finalize.
1988  * @param ptr The pointer to the remaining input.
1989  * @param len The remaining length, modulo 16.
1990  * @param align Whether @p ptr is aligned.
1991  * @return The finalized hash.
1992  */
1993 static xxh_u32
XXH32_finalize(xxh_u32 h32,const xxh_u8 * ptr,size_t len,XXH_alignment align)1994 XXH32_finalize(xxh_u32 h32, const xxh_u8* ptr, size_t len, XXH_alignment align)
1995 {
1996 #define XXH_PROCESS1 do {                           \
1997     h32 += (*ptr++) * XXH_PRIME32_5;                \
1998     h32 = XXH_rotl32(h32, 11) * XXH_PRIME32_1;      \
1999 } while (0)
2000 
2001 #define XXH_PROCESS4 do {                           \
2002     h32 += XXH_get32bits(ptr) * XXH_PRIME32_3;      \
2003     ptr += 4;                                   \
2004     h32  = XXH_rotl32(h32, 17) * XXH_PRIME32_4;     \
2005 } while (0)
2006 
2007     if (ptr==NULL) XXH_ASSERT(len == 0);
2008 
2009     /* Compact rerolled version; generally faster */
2010     if (!XXH32_ENDJMP) {
2011         len &= 15;
2012         while (len >= 4) {
2013             XXH_PROCESS4;
2014             len -= 4;
2015         }
2016         while (len > 0) {
2017             XXH_PROCESS1;
2018             --len;
2019         }
2020         return XXH32_avalanche(h32);
2021     } else {
2022          switch(len&15) /* or switch(bEnd - p) */ {
2023            case 12:      XXH_PROCESS4;
2024                          XXH_FALLTHROUGH;
2025            case 8:       XXH_PROCESS4;
2026                          XXH_FALLTHROUGH;
2027            case 4:       XXH_PROCESS4;
2028                          return XXH32_avalanche(h32);
2029 
2030            case 13:      XXH_PROCESS4;
2031                          XXH_FALLTHROUGH;
2032            case 9:       XXH_PROCESS4;
2033                          XXH_FALLTHROUGH;
2034            case 5:       XXH_PROCESS4;
2035                          XXH_PROCESS1;
2036                          return XXH32_avalanche(h32);
2037 
2038            case 14:      XXH_PROCESS4;
2039                          XXH_FALLTHROUGH;
2040            case 10:      XXH_PROCESS4;
2041                          XXH_FALLTHROUGH;
2042            case 6:       XXH_PROCESS4;
2043                          XXH_PROCESS1;
2044                          XXH_PROCESS1;
2045                          return XXH32_avalanche(h32);
2046 
2047            case 15:      XXH_PROCESS4;
2048                          XXH_FALLTHROUGH;
2049            case 11:      XXH_PROCESS4;
2050                          XXH_FALLTHROUGH;
2051            case 7:       XXH_PROCESS4;
2052                          XXH_FALLTHROUGH;
2053            case 3:       XXH_PROCESS1;
2054                          XXH_FALLTHROUGH;
2055            case 2:       XXH_PROCESS1;
2056                          XXH_FALLTHROUGH;
2057            case 1:       XXH_PROCESS1;
2058                          XXH_FALLTHROUGH;
2059            case 0:       return XXH32_avalanche(h32);
2060         }
2061         XXH_ASSERT(0);
2062         return h32;   /* reaching this point is deemed impossible */
2063     }
2064 }
2065 
2066 #ifdef XXH_OLD_NAMES
2067 #  define PROCESS1 XXH_PROCESS1
2068 #  define PROCESS4 XXH_PROCESS4
2069 #else
2070 #  undef XXH_PROCESS1
2071 #  undef XXH_PROCESS4
2072 #endif
2073 
2074 /*!
2075  * @internal
2076  * @brief The implementation for @ref XXH32().
2077  *
2078  * @param input , len , seed Directly passed from @ref XXH32().
2079  * @param align Whether @p input is aligned.
2080  * @return The calculated hash.
2081  */
2082 XXH_FORCE_INLINE xxh_u32
XXH32_endian_align(const xxh_u8 * input,size_t len,xxh_u32 seed,XXH_alignment align)2083 XXH32_endian_align(const xxh_u8* input, size_t len, xxh_u32 seed, XXH_alignment align)
2084 {
2085     xxh_u32 h32;
2086 
2087     if (input==NULL) XXH_ASSERT(len == 0);
2088 
2089     if (len>=16) {
2090         const xxh_u8* const bEnd = input + len;
2091         const xxh_u8* const limit = bEnd - 15;
2092         xxh_u32 v1 = seed + XXH_PRIME32_1 + XXH_PRIME32_2;
2093         xxh_u32 v2 = seed + XXH_PRIME32_2;
2094         xxh_u32 v3 = seed + 0;
2095         xxh_u32 v4 = seed - XXH_PRIME32_1;
2096 
2097         do {
2098             v1 = XXH32_round(v1, XXH_get32bits(input)); input += 4;
2099             v2 = XXH32_round(v2, XXH_get32bits(input)); input += 4;
2100             v3 = XXH32_round(v3, XXH_get32bits(input)); input += 4;
2101             v4 = XXH32_round(v4, XXH_get32bits(input)); input += 4;
2102         } while (input < limit);
2103 
2104         h32 = XXH_rotl32(v1, 1)  + XXH_rotl32(v2, 7)
2105             + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
2106     } else {
2107         h32  = seed + XXH_PRIME32_5;
2108     }
2109 
2110     h32 += (xxh_u32)len;
2111 
2112     return XXH32_finalize(h32, input, len&15, align);
2113 }
2114 
2115 /*! @ingroup xxh32_family */
XXH32(const void * input,size_t len,XXH32_hash_t seed)2116 XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t len, XXH32_hash_t seed)
2117 {
2118 #if 0
2119     /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
2120     XXH32_state_t state;
2121     XXH32_reset(&state, seed);
2122     XXH32_update(&state, (const xxh_u8*)input, len);
2123     return XXH32_digest(&state);
2124 #else
2125     if (XXH_FORCE_ALIGN_CHECK) {
2126         if ((((size_t)input) & 3) == 0) {   /* Input is 4-bytes aligned, leverage the speed benefit */
2127             return XXH32_endian_align((const xxh_u8*)input, len, seed, XXH_aligned);
2128     }   }
2129 
2130     return XXH32_endian_align((const xxh_u8*)input, len, seed, XXH_unaligned);
2131 #endif
2132 }
2133 
2134 
2135 
2136 /*******   Hash streaming   *******/
2137 /*!
2138  * @ingroup xxh32_family
2139  */
XXH32_createState(void)2140 XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
2141 {
2142     return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
2143 }
2144 /*! @ingroup xxh32_family */
XXH32_freeState(XXH32_state_t * statePtr)2145 XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
2146 {
2147     XXH_free(statePtr);
2148     return XXH_OK;
2149 }
2150 
2151 /*! @ingroup xxh32_family */
XXH32_copyState(XXH32_state_t * dstState,const XXH32_state_t * srcState)2152 XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState)
2153 {
2154     XXH_memcpy(dstState, srcState, sizeof(*dstState));
2155 }
2156 
2157 /*! @ingroup xxh32_family */
XXH32_reset(XXH32_state_t * statePtr,XXH32_hash_t seed)2158 XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, XXH32_hash_t seed)
2159 {
2160     XXH32_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
2161     memset(&state, 0, sizeof(state));
2162     state.v[0] = seed + XXH_PRIME32_1 + XXH_PRIME32_2;
2163     state.v[1] = seed + XXH_PRIME32_2;
2164     state.v[2] = seed + 0;
2165     state.v[3] = seed - XXH_PRIME32_1;
2166     /* do not write into reserved, planned to be removed in a future version */
2167     XXH_memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved));
2168     return XXH_OK;
2169 }
2170 
2171 
2172 /*! @ingroup xxh32_family */
2173 XXH_PUBLIC_API XXH_errorcode
XXH32_update(XXH32_state_t * state,const void * input,size_t len)2174 XXH32_update(XXH32_state_t* state, const void* input, size_t len)
2175 {
2176     if (input==NULL) {
2177         XXH_ASSERT(len == 0);
2178         return XXH_OK;
2179     }
2180 
2181     {   const xxh_u8* p = (const xxh_u8*)input;
2182         const xxh_u8* const bEnd = p + len;
2183 
2184         state->total_len_32 += (XXH32_hash_t)len;
2185         state->large_len |= (XXH32_hash_t)((len>=16) | (state->total_len_32>=16));
2186 
2187         if (state->memsize + len < 16)  {   /* fill in tmp buffer */
2188             XXH_memcpy((xxh_u8*)(state->mem32) + state->memsize, input, len);
2189             state->memsize += (XXH32_hash_t)len;
2190             return XXH_OK;
2191         }
2192 
2193         if (state->memsize) {   /* some data left from previous update */
2194             XXH_memcpy((xxh_u8*)(state->mem32) + state->memsize, input, 16-state->memsize);
2195             {   const xxh_u32* p32 = state->mem32;
2196                 state->v[0] = XXH32_round(state->v[0], XXH_readLE32(p32)); p32++;
2197                 state->v[1] = XXH32_round(state->v[1], XXH_readLE32(p32)); p32++;
2198                 state->v[2] = XXH32_round(state->v[2], XXH_readLE32(p32)); p32++;
2199                 state->v[3] = XXH32_round(state->v[3], XXH_readLE32(p32));
2200             }
2201             p += 16-state->memsize;
2202             state->memsize = 0;
2203         }
2204 
2205         if (p <= bEnd-16) {
2206             const xxh_u8* const limit = bEnd - 16;
2207 
2208             do {
2209                 state->v[0] = XXH32_round(state->v[0], XXH_readLE32(p)); p+=4;
2210                 state->v[1] = XXH32_round(state->v[1], XXH_readLE32(p)); p+=4;
2211                 state->v[2] = XXH32_round(state->v[2], XXH_readLE32(p)); p+=4;
2212                 state->v[3] = XXH32_round(state->v[3], XXH_readLE32(p)); p+=4;
2213             } while (p<=limit);
2214 
2215         }
2216 
2217         if (p < bEnd) {
2218             XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
2219             state->memsize = (unsigned)(bEnd-p);
2220         }
2221     }
2222 
2223     return XXH_OK;
2224 }
2225 
2226 
2227 /*! @ingroup xxh32_family */
XXH32_digest(const XXH32_state_t * state)2228 XXH_PUBLIC_API XXH32_hash_t XXH32_digest(const XXH32_state_t* state)
2229 {
2230     xxh_u32 h32;
2231 
2232     if (state->large_len) {
2233         h32 = XXH_rotl32(state->v[0], 1)
2234             + XXH_rotl32(state->v[1], 7)
2235             + XXH_rotl32(state->v[2], 12)
2236             + XXH_rotl32(state->v[3], 18);
2237     } else {
2238         h32 = state->v[2] /* == seed */ + XXH_PRIME32_5;
2239     }
2240 
2241     h32 += state->total_len_32;
2242 
2243     return XXH32_finalize(h32, (const xxh_u8*)state->mem32, state->memsize, XXH_aligned);
2244 }
2245 
2246 
2247 /*******   Canonical representation   *******/
2248 
2249 /*!
2250  * @ingroup xxh32_family
2251  * The default return values from XXH functions are unsigned 32 and 64 bit
2252  * integers.
2253  *
2254  * The canonical representation uses big endian convention, the same convention
2255  * as human-readable numbers (large digits first).
2256  *
2257  * This way, hash values can be written into a file or buffer, remaining
2258  * comparable across different systems.
2259  *
2260  * The following functions allow transformation of hash values to and from their
2261  * canonical format.
2262  */
XXH32_canonicalFromHash(XXH32_canonical_t * dst,XXH32_hash_t hash)2263 XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
2264 {
2265     XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t));
2266     if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
2267     XXH_memcpy(dst, &hash, sizeof(*dst));
2268 }
2269 /*! @ingroup xxh32_family */
XXH32_hashFromCanonical(const XXH32_canonical_t * src)2270 XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
2271 {
2272     return XXH_readBE32(src);
2273 }
2274 
2275 
2276 #ifndef XXH_NO_LONG_LONG
2277 
2278 /* *******************************************************************
2279 *  64-bit hash functions
2280 *********************************************************************/
2281 /*!
2282  * @}
2283  * @ingroup impl
2284  * @{
2285  */
2286 /*******   Memory access   *******/
2287 
2288 typedef XXH64_hash_t xxh_u64;
2289 
2290 #ifdef XXH_OLD_NAMES
2291 #  define U64 xxh_u64
2292 #endif
2293 
2294 #if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
2295 /*
2296  * Manual byteshift. Best for old compilers which don't inline memcpy.
2297  * We actually directly use XXH_readLE64 and XXH_readBE64.
2298  */
2299 #elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
2300 
2301 /* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
XXH_read64(const void * memPtr)2302 static xxh_u64 XXH_read64(const void* memPtr)
2303 {
2304     return *(const xxh_u64*) memPtr;
2305 }
2306 
2307 #elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
2308 
2309 /*
2310  * __pack instructions are safer, but compiler specific, hence potentially
2311  * problematic for some compilers.
2312  *
2313  * Currently only defined for GCC and ICC.
2314  */
2315 #ifdef XXH_OLD_NAMES
2316 typedef union { xxh_u32 u32; xxh_u64 u64; } __attribute__((packed)) unalign64;
2317 #endif
XXH_read64(const void * ptr)2318 static xxh_u64 XXH_read64(const void* ptr)
2319 {
2320     typedef union { xxh_u32 u32; xxh_u64 u64; } __attribute__((packed)) xxh_unalign64;
2321     return ((const xxh_unalign64*)ptr)->u64;
2322 }
2323 
2324 #else
2325 
2326 /*
2327  * Portable and safe solution. Generally efficient.
2328  * see: http://fastcompression.blogspot.com/2015/08/accessing-unaligned-memory.html
2329  */
XXH_read64(const void * memPtr)2330 static xxh_u64 XXH_read64(const void* memPtr)
2331 {
2332     xxh_u64 val;
2333     XXH_memcpy(&val, memPtr, sizeof(val));
2334     return val;
2335 }
2336 
2337 #endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
2338 
2339 #if defined(_MSC_VER)     /* Visual Studio */
2340 #  define XXH_swap64 _byteswap_uint64
2341 #elif XXH_GCC_VERSION >= 403
2342 #  define XXH_swap64 __builtin_bswap64
2343 #else
XXH_swap64(xxh_u64 x)2344 static xxh_u64 XXH_swap64(xxh_u64 x)
2345 {
2346     return  ((x << 56) & 0xff00000000000000ULL) |
2347             ((x << 40) & 0x00ff000000000000ULL) |
2348             ((x << 24) & 0x0000ff0000000000ULL) |
2349             ((x << 8)  & 0x000000ff00000000ULL) |
2350             ((x >> 8)  & 0x00000000ff000000ULL) |
2351             ((x >> 24) & 0x0000000000ff0000ULL) |
2352             ((x >> 40) & 0x000000000000ff00ULL) |
2353             ((x >> 56) & 0x00000000000000ffULL);
2354 }
2355 #endif
2356 
2357 
2358 /* XXH_FORCE_MEMORY_ACCESS==3 is an endian-independent byteshift load. */
2359 #if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==3))
2360 
XXH_readLE64(const void * memPtr)2361 XXH_FORCE_INLINE xxh_u64 XXH_readLE64(const void* memPtr)
2362 {
2363     const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
2364     return bytePtr[0]
2365          | ((xxh_u64)bytePtr[1] << 8)
2366          | ((xxh_u64)bytePtr[2] << 16)
2367          | ((xxh_u64)bytePtr[3] << 24)
2368          | ((xxh_u64)bytePtr[4] << 32)
2369          | ((xxh_u64)bytePtr[5] << 40)
2370          | ((xxh_u64)bytePtr[6] << 48)
2371          | ((xxh_u64)bytePtr[7] << 56);
2372 }
2373 
XXH_readBE64(const void * memPtr)2374 XXH_FORCE_INLINE xxh_u64 XXH_readBE64(const void* memPtr)
2375 {
2376     const xxh_u8* bytePtr = (const xxh_u8 *)memPtr;
2377     return bytePtr[7]
2378          | ((xxh_u64)bytePtr[6] << 8)
2379          | ((xxh_u64)bytePtr[5] << 16)
2380          | ((xxh_u64)bytePtr[4] << 24)
2381          | ((xxh_u64)bytePtr[3] << 32)
2382          | ((xxh_u64)bytePtr[2] << 40)
2383          | ((xxh_u64)bytePtr[1] << 48)
2384          | ((xxh_u64)bytePtr[0] << 56);
2385 }
2386 
2387 #else
XXH_readLE64(const void * ptr)2388 XXH_FORCE_INLINE xxh_u64 XXH_readLE64(const void* ptr)
2389 {
2390     return XXH_CPU_LITTLE_ENDIAN ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
2391 }
2392 
XXH_readBE64(const void * ptr)2393 static xxh_u64 XXH_readBE64(const void* ptr)
2394 {
2395     return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
2396 }
2397 #endif
2398 
2399 XXH_FORCE_INLINE xxh_u64
XXH_readLE64_align(const void * ptr,XXH_alignment align)2400 XXH_readLE64_align(const void* ptr, XXH_alignment align)
2401 {
2402     if (align==XXH_unaligned)
2403         return XXH_readLE64(ptr);
2404     else
2405         return XXH_CPU_LITTLE_ENDIAN ? *(const xxh_u64*)ptr : XXH_swap64(*(const xxh_u64*)ptr);
2406 }
2407 
2408 
2409 /*******   xxh64   *******/
2410 /*!
2411  * @}
2412  * @defgroup xxh64_impl XXH64 implementation
2413  * @ingroup impl
2414  * @{
2415  */
2416 /* #define rather that static const, to be used as initializers */
2417 #define XXH_PRIME64_1  0x9E3779B185EBCA87ULL  /*!< 0b1001111000110111011110011011000110000101111010111100101010000111 */
2418 #define XXH_PRIME64_2  0xC2B2AE3D27D4EB4FULL  /*!< 0b1100001010110010101011100011110100100111110101001110101101001111 */
2419 #define XXH_PRIME64_3  0x165667B19E3779F9ULL  /*!< 0b0001011001010110011001111011000110011110001101110111100111111001 */
2420 #define XXH_PRIME64_4  0x85EBCA77C2B2AE63ULL  /*!< 0b1000010111101011110010100111011111000010101100101010111001100011 */
2421 #define XXH_PRIME64_5  0x27D4EB2F165667C5ULL  /*!< 0b0010011111010100111010110010111100010110010101100110011111000101 */
2422 
2423 #ifdef XXH_OLD_NAMES
2424 #  define PRIME64_1 XXH_PRIME64_1
2425 #  define PRIME64_2 XXH_PRIME64_2
2426 #  define PRIME64_3 XXH_PRIME64_3
2427 #  define PRIME64_4 XXH_PRIME64_4
2428 #  define PRIME64_5 XXH_PRIME64_5
2429 #endif
2430 
XXH64_round(xxh_u64 acc,xxh_u64 input)2431 static xxh_u64 XXH64_round(xxh_u64 acc, xxh_u64 input)
2432 {
2433     acc += input * XXH_PRIME64_2;
2434     acc  = XXH_rotl64(acc, 31);
2435     acc *= XXH_PRIME64_1;
2436     return acc;
2437 }
2438 
XXH64_mergeRound(xxh_u64 acc,xxh_u64 val)2439 static xxh_u64 XXH64_mergeRound(xxh_u64 acc, xxh_u64 val)
2440 {
2441     val  = XXH64_round(0, val);
2442     acc ^= val;
2443     acc  = acc * XXH_PRIME64_1 + XXH_PRIME64_4;
2444     return acc;
2445 }
2446 
XXH64_avalanche(xxh_u64 h64)2447 static xxh_u64 XXH64_avalanche(xxh_u64 h64)
2448 {
2449     h64 ^= h64 >> 33;
2450     h64 *= XXH_PRIME64_2;
2451     h64 ^= h64 >> 29;
2452     h64 *= XXH_PRIME64_3;
2453     h64 ^= h64 >> 32;
2454     return h64;
2455 }
2456 
2457 
2458 #define XXH_get64bits(p) XXH_readLE64_align(p, align)
2459 
2460 static xxh_u64
XXH64_finalize(xxh_u64 h64,const xxh_u8 * ptr,size_t len,XXH_alignment align)2461 XXH64_finalize(xxh_u64 h64, const xxh_u8* ptr, size_t len, XXH_alignment align)
2462 {
2463     if (ptr==NULL) XXH_ASSERT(len == 0);
2464     len &= 31;
2465     while (len >= 8) {
2466         xxh_u64 const k1 = XXH64_round(0, XXH_get64bits(ptr));
2467         ptr += 8;
2468         h64 ^= k1;
2469         h64  = XXH_rotl64(h64,27) * XXH_PRIME64_1 + XXH_PRIME64_4;
2470         len -= 8;
2471     }
2472     if (len >= 4) {
2473         h64 ^= (xxh_u64)(XXH_get32bits(ptr)) * XXH_PRIME64_1;
2474         ptr += 4;
2475         h64 = XXH_rotl64(h64, 23) * XXH_PRIME64_2 + XXH_PRIME64_3;
2476         len -= 4;
2477     }
2478     while (len > 0) {
2479         h64 ^= (*ptr++) * XXH_PRIME64_5;
2480         h64 = XXH_rotl64(h64, 11) * XXH_PRIME64_1;
2481         --len;
2482     }
2483     return  XXH64_avalanche(h64);
2484 }
2485 
2486 #ifdef XXH_OLD_NAMES
2487 #  define PROCESS1_64 XXH_PROCESS1_64
2488 #  define PROCESS4_64 XXH_PROCESS4_64
2489 #  define PROCESS8_64 XXH_PROCESS8_64
2490 #else
2491 #  undef XXH_PROCESS1_64
2492 #  undef XXH_PROCESS4_64
2493 #  undef XXH_PROCESS8_64
2494 #endif
2495 
2496 XXH_FORCE_INLINE xxh_u64
XXH64_endian_align(const xxh_u8 * input,size_t len,xxh_u64 seed,XXH_alignment align)2497 XXH64_endian_align(const xxh_u8* input, size_t len, xxh_u64 seed, XXH_alignment align)
2498 {
2499     xxh_u64 h64;
2500     if (input==NULL) XXH_ASSERT(len == 0);
2501 
2502     if (len>=32) {
2503         const xxh_u8* const bEnd = input + len;
2504         const xxh_u8* const limit = bEnd - 31;
2505         xxh_u64 v1 = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
2506         xxh_u64 v2 = seed + XXH_PRIME64_2;
2507         xxh_u64 v3 = seed + 0;
2508         xxh_u64 v4 = seed - XXH_PRIME64_1;
2509 
2510         do {
2511             v1 = XXH64_round(v1, XXH_get64bits(input)); input+=8;
2512             v2 = XXH64_round(v2, XXH_get64bits(input)); input+=8;
2513             v3 = XXH64_round(v3, XXH_get64bits(input)); input+=8;
2514             v4 = XXH64_round(v4, XXH_get64bits(input)); input+=8;
2515         } while (input<limit);
2516 
2517         h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
2518         h64 = XXH64_mergeRound(h64, v1);
2519         h64 = XXH64_mergeRound(h64, v2);
2520         h64 = XXH64_mergeRound(h64, v3);
2521         h64 = XXH64_mergeRound(h64, v4);
2522 
2523     } else {
2524         h64  = seed + XXH_PRIME64_5;
2525     }
2526 
2527     h64 += (xxh_u64) len;
2528 
2529     return XXH64_finalize(h64, input, len, align);
2530 }
2531 
2532 
2533 /*! @ingroup xxh64_family */
XXH64(const void * input,size_t len,XXH64_hash_t seed)2534 XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t len, XXH64_hash_t seed)
2535 {
2536 #if 0
2537     /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
2538     XXH64_state_t state;
2539     XXH64_reset(&state, seed);
2540     XXH64_update(&state, (const xxh_u8*)input, len);
2541     return XXH64_digest(&state);
2542 #else
2543     if (XXH_FORCE_ALIGN_CHECK) {
2544         if ((((size_t)input) & 7)==0) {  /* Input is aligned, let's leverage the speed advantage */
2545             return XXH64_endian_align((const xxh_u8*)input, len, seed, XXH_aligned);
2546     }   }
2547 
2548     return XXH64_endian_align((const xxh_u8*)input, len, seed, XXH_unaligned);
2549 
2550 #endif
2551 }
2552 
2553 /*******   Hash Streaming   *******/
2554 
2555 /*! @ingroup xxh64_family*/
XXH64_createState(void)2556 XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
2557 {
2558     return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
2559 }
2560 /*! @ingroup xxh64_family */
XXH64_freeState(XXH64_state_t * statePtr)2561 XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
2562 {
2563     XXH_free(statePtr);
2564     return XXH_OK;
2565 }
2566 
2567 /*! @ingroup xxh64_family */
XXH64_copyState(XXH64_state_t * dstState,const XXH64_state_t * srcState)2568 XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState)
2569 {
2570     XXH_memcpy(dstState, srcState, sizeof(*dstState));
2571 }
2572 
2573 /*! @ingroup xxh64_family */
XXH64_reset(XXH64_state_t * statePtr,XXH64_hash_t seed)2574 XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, XXH64_hash_t seed)
2575 {
2576     XXH64_state_t state;   /* use a local state to memcpy() in order to avoid strict-aliasing warnings */
2577     memset(&state, 0, sizeof(state));
2578     state.v[0] = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
2579     state.v[1] = seed + XXH_PRIME64_2;
2580     state.v[2] = seed + 0;
2581     state.v[3] = seed - XXH_PRIME64_1;
2582      /* do not write into reserved64, might be removed in a future version */
2583     XXH_memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved64));
2584     return XXH_OK;
2585 }
2586 
2587 /*! @ingroup xxh64_family */
2588 XXH_PUBLIC_API XXH_errorcode
XXH64_update(XXH64_state_t * state,const void * input,size_t len)2589 XXH64_update (XXH64_state_t* state, const void* input, size_t len)
2590 {
2591     if (input==NULL) {
2592         XXH_ASSERT(len == 0);
2593         return XXH_OK;
2594     }
2595 
2596     {   const xxh_u8* p = (const xxh_u8*)input;
2597         const xxh_u8* const bEnd = p + len;
2598 
2599         state->total_len += len;
2600 
2601         if (state->memsize + len < 32) {  /* fill in tmp buffer */
2602             XXH_memcpy(((xxh_u8*)state->mem64) + state->memsize, input, len);
2603             state->memsize += (xxh_u32)len;
2604             return XXH_OK;
2605         }
2606 
2607         if (state->memsize) {   /* tmp buffer is full */
2608             XXH_memcpy(((xxh_u8*)state->mem64) + state->memsize, input, 32-state->memsize);
2609             state->v[0] = XXH64_round(state->v[0], XXH_readLE64(state->mem64+0));
2610             state->v[1] = XXH64_round(state->v[1], XXH_readLE64(state->mem64+1));
2611             state->v[2] = XXH64_round(state->v[2], XXH_readLE64(state->mem64+2));
2612             state->v[3] = XXH64_round(state->v[3], XXH_readLE64(state->mem64+3));
2613             p += 32 - state->memsize;
2614             state->memsize = 0;
2615         }
2616 
2617         if (p+32 <= bEnd) {
2618             const xxh_u8* const limit = bEnd - 32;
2619 
2620             do {
2621                 state->v[0] = XXH64_round(state->v[0], XXH_readLE64(p)); p+=8;
2622                 state->v[1] = XXH64_round(state->v[1], XXH_readLE64(p)); p+=8;
2623                 state->v[2] = XXH64_round(state->v[2], XXH_readLE64(p)); p+=8;
2624                 state->v[3] = XXH64_round(state->v[3], XXH_readLE64(p)); p+=8;
2625             } while (p<=limit);
2626 
2627         }
2628 
2629         if (p < bEnd) {
2630             XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
2631             state->memsize = (unsigned)(bEnd-p);
2632         }
2633     }
2634 
2635     return XXH_OK;
2636 }
2637 
2638 
2639 /*! @ingroup xxh64_family */
XXH64_digest(const XXH64_state_t * state)2640 XXH_PUBLIC_API XXH64_hash_t XXH64_digest(const XXH64_state_t* state)
2641 {
2642     xxh_u64 h64;
2643 
2644     if (state->total_len >= 32) {
2645         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);
2646         h64 = XXH64_mergeRound(h64, state->v[0]);
2647         h64 = XXH64_mergeRound(h64, state->v[1]);
2648         h64 = XXH64_mergeRound(h64, state->v[2]);
2649         h64 = XXH64_mergeRound(h64, state->v[3]);
2650     } else {
2651         h64  = state->v[2] /*seed*/ + XXH_PRIME64_5;
2652     }
2653 
2654     h64 += (xxh_u64) state->total_len;
2655 
2656     return XXH64_finalize(h64, (const xxh_u8*)state->mem64, (size_t)state->total_len, XXH_aligned);
2657 }
2658 
2659 
2660 /******* Canonical representation   *******/
2661 
2662 /*! @ingroup xxh64_family */
XXH64_canonicalFromHash(XXH64_canonical_t * dst,XXH64_hash_t hash)2663 XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
2664 {
2665     XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t));
2666     if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
2667     XXH_memcpy(dst, &hash, sizeof(*dst));
2668 }
2669 
2670 /*! @ingroup xxh64_family */
XXH64_hashFromCanonical(const XXH64_canonical_t * src)2671 XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
2672 {
2673     return XXH_readBE64(src);
2674 }
2675 
2676 #ifndef XXH_NO_XXH3
2677 
2678 /* *********************************************************************
2679 *  XXH3
2680 *  New generation hash designed for speed on small keys and vectorization
2681 ************************************************************************ */
2682 /*!
2683  * @}
2684  * @defgroup xxh3_impl XXH3 implementation
2685  * @ingroup impl
2686  * @{
2687  */
2688 
2689 /* ===   Compiler specifics   === */
2690 
2691 #if ((defined(sun) || defined(__sun)) && __cplusplus) /* Solaris includes __STDC_VERSION__ with C++. Tested with GCC 5.5 */
2692 #  define XXH_RESTRICT /* disable */
2693 #elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* >= C99 */
2694 #  define XXH_RESTRICT   restrict
2695 #else
2696 /* Note: it might be useful to define __restrict or __restrict__ for some C++ compilers */
2697 #  define XXH_RESTRICT   /* disable */
2698 #endif
2699 
2700 #if (defined(__GNUC__) && (__GNUC__ >= 3))  \
2701   || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) \
2702   || defined(__clang__)
2703 #    define XXH_likely(x) __builtin_expect(x, 1)
2704 #    define XXH_unlikely(x) __builtin_expect(x, 0)
2705 #else
2706 #    define XXH_likely(x) (x)
2707 #    define XXH_unlikely(x) (x)
2708 #endif
2709 
2710 #if defined(__GNUC__)
2711 #  if defined(__AVX2__)
2712 #    include <immintrin.h>
2713 #  elif defined(__SSE2__)
2714 #    include <emmintrin.h>
2715 #  elif defined(__ARM_NEON__) || defined(__ARM_NEON)
2716 #    define inline __inline__  /* circumvent a clang bug */
2717 #    include <arm_neon.h>
2718 #    undef inline
2719 #  endif
2720 #elif defined(_MSC_VER)
2721 #  include <intrin.h>
2722 #endif
2723 
2724 /*
2725  * One goal of XXH3 is to make it fast on both 32-bit and 64-bit, while
2726  * remaining a true 64-bit/128-bit hash function.
2727  *
2728  * This is done by prioritizing a subset of 64-bit operations that can be
2729  * emulated without too many steps on the average 32-bit machine.
2730  *
2731  * For example, these two lines seem similar, and run equally fast on 64-bit:
2732  *
2733  *   xxh_u64 x;
2734  *   x ^= (x >> 47); // good
2735  *   x ^= (x >> 13); // bad
2736  *
2737  * However, to a 32-bit machine, there is a major difference.
2738  *
2739  * x ^= (x >> 47) looks like this:
2740  *
2741  *   x.lo ^= (x.hi >> (47 - 32));
2742  *
2743  * while x ^= (x >> 13) looks like this:
2744  *
2745  *   // note: funnel shifts are not usually cheap.
2746  *   x.lo ^= (x.lo >> 13) | (x.hi << (32 - 13));
2747  *   x.hi ^= (x.hi >> 13);
2748  *
2749  * The first one is significantly faster than the second, simply because the
2750  * shift is larger than 32. This means:
2751  *  - All the bits we need are in the upper 32 bits, so we can ignore the lower
2752  *    32 bits in the shift.
2753  *  - The shift result will always fit in the lower 32 bits, and therefore,
2754  *    we can ignore the upper 32 bits in the xor.
2755  *
2756  * Thanks to this optimization, XXH3 only requires these features to be efficient:
2757  *
2758  *  - Usable unaligned access
2759  *  - A 32-bit or 64-bit ALU
2760  *      - If 32-bit, a decent ADC instruction
2761  *  - A 32 or 64-bit multiply with a 64-bit result
2762  *  - For the 128-bit variant, a decent byteswap helps short inputs.
2763  *
2764  * The first two are already required by XXH32, and almost all 32-bit and 64-bit
2765  * platforms which can run XXH32 can run XXH3 efficiently.
2766  *
2767  * Thumb-1, the classic 16-bit only subset of ARM's instruction set, is one
2768  * notable exception.
2769  *
2770  * First of all, Thumb-1 lacks support for the UMULL instruction which
2771  * performs the important long multiply. This means numerous __aeabi_lmul
2772  * calls.
2773  *
2774  * Second of all, the 8 functional registers are just not enough.
2775  * Setup for __aeabi_lmul, byteshift loads, pointers, and all arithmetic need
2776  * Lo registers, and this shuffling results in thousands more MOVs than A32.
2777  *
2778  * A32 and T32 don't have this limitation. They can access all 14 registers,
2779  * do a 32->64 multiply with UMULL, and the flexible operand allowing free
2780  * shifts is helpful, too.
2781  *
2782  * Therefore, we do a quick sanity check.
2783  *
2784  * If compiling Thumb-1 for a target which supports ARM instructions, we will
2785  * emit a warning, as it is not a "sane" platform to compile for.
2786  *
2787  * Usually, if this happens, it is because of an accident and you probably need
2788  * to specify -march, as you likely meant to compile for a newer architecture.
2789  *
2790  * Credit: large sections of the vectorial and asm source code paths
2791  *         have been contributed by @easyaspi314
2792  */
2793 #if defined(__thumb__) && !defined(__thumb2__) && defined(__ARM_ARCH_ISA_ARM)
2794 #   warning "XXH3 is highly inefficient without ARM or Thumb-2."
2795 #endif
2796 
2797 /* ==========================================
2798  * Vectorization detection
2799  * ========================================== */
2800 
2801 #ifdef XXH_DOXYGEN
2802 /*!
2803  * @ingroup tuning
2804  * @brief Overrides the vectorization implementation chosen for XXH3.
2805  *
2806  * Can be defined to 0 to disable SIMD or any of the values mentioned in
2807  * @ref XXH_VECTOR_TYPE.
2808  *
2809  * If this is not defined, it uses predefined macros to determine the best
2810  * implementation.
2811  */
2812 #  define XXH_VECTOR XXH_SCALAR
2813 /*!
2814  * @ingroup tuning
2815  * @brief Possible values for @ref XXH_VECTOR.
2816  *
2817  * Note that these are actually implemented as macros.
2818  *
2819  * If this is not defined, it is detected automatically.
2820  * @ref XXH_X86DISPATCH overrides this.
2821  */
2822 enum XXH_VECTOR_TYPE /* fake enum */ {
2823     XXH_SCALAR = 0,  /*!< Portable scalar version */
2824     XXH_SSE2   = 1,  /*!<
2825                       * SSE2 for Pentium 4, Opteron, all x86_64.
2826                       *
2827                       * @note SSE2 is also guaranteed on Windows 10, macOS, and
2828                       * Android x86.
2829                       */
2830     XXH_AVX2   = 2,  /*!< AVX2 for Haswell and Bulldozer */
2831     XXH_AVX512 = 3,  /*!< AVX512 for Skylake and Icelake */
2832     XXH_NEON   = 4,  /*!< NEON for most ARMv7-A and all AArch64 */
2833     XXH_VSX    = 5,  /*!< VSX and ZVector for POWER8/z13 (64-bit) */
2834 };
2835 /*!
2836  * @ingroup tuning
2837  * @brief Selects the minimum alignment for XXH3's accumulators.
2838  *
2839  * When using SIMD, this should match the alignment reqired for said vector
2840  * type, so, for example, 32 for AVX2.
2841  *
2842  * Default: Auto detected.
2843  */
2844 #  define XXH_ACC_ALIGN 8
2845 #endif
2846 
2847 /* Actual definition */
2848 #ifndef XXH_DOXYGEN
2849 #  define XXH_SCALAR 0
2850 #  define XXH_SSE2   1
2851 #  define XXH_AVX2   2
2852 #  define XXH_AVX512 3
2853 #  define XXH_NEON   4
2854 #  define XXH_VSX    5
2855 #endif
2856 
2857 #ifndef XXH_VECTOR    /* can be defined on command line */
2858 #  if defined(__AVX512F__)
2859 #    define XXH_VECTOR XXH_AVX512
2860 #  elif defined(__AVX2__)
2861 #    define XXH_VECTOR XXH_AVX2
2862 #  elif defined(__SSE2__) || defined(_M_AMD64) || defined(_M_X64) || (defined(_M_IX86_FP) && (_M_IX86_FP == 2))
2863 #    define XXH_VECTOR XXH_SSE2
2864 #  elif ( \
2865         defined(__ARM_NEON__) || defined(__ARM_NEON) /* gcc */ \
2866      || defined(_M_ARM64) || defined(_M_ARM_ARMV7VE) /* msvc */ \
2867    ) && ( \
2868         defined(_WIN32) || defined(__LITTLE_ENDIAN__) /* little endian only */ \
2869     || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) \
2870    )
2871 #    define XXH_VECTOR XXH_NEON
2872 #  elif (defined(__PPC64__) && defined(__POWER8_VECTOR__)) \
2873      || (defined(__s390x__) && defined(__VEC__)) \
2874      && defined(__GNUC__) /* TODO: IBM XL */
2875 #    define XXH_VECTOR XXH_VSX
2876 #  else
2877 #    define XXH_VECTOR XXH_SCALAR
2878 #  endif
2879 #endif
2880 
2881 /*
2882  * Controls the alignment of the accumulator,
2883  * for compatibility with aligned vector loads, which are usually faster.
2884  */
2885 #ifndef XXH_ACC_ALIGN
2886 #  if defined(XXH_X86DISPATCH)
2887 #     define XXH_ACC_ALIGN 64  /* for compatibility with avx512 */
2888 #  elif XXH_VECTOR == XXH_SCALAR  /* scalar */
2889 #     define XXH_ACC_ALIGN 8
2890 #  elif XXH_VECTOR == XXH_SSE2  /* sse2 */
2891 #     define XXH_ACC_ALIGN 16
2892 #  elif XXH_VECTOR == XXH_AVX2  /* avx2 */
2893 #     define XXH_ACC_ALIGN 32
2894 #  elif XXH_VECTOR == XXH_NEON  /* neon */
2895 #     define XXH_ACC_ALIGN 16
2896 #  elif XXH_VECTOR == XXH_VSX   /* vsx */
2897 #     define XXH_ACC_ALIGN 16
2898 #  elif XXH_VECTOR == XXH_AVX512  /* avx512 */
2899 #     define XXH_ACC_ALIGN 64
2900 #  endif
2901 #endif
2902 
2903 #if defined(XXH_X86DISPATCH) || XXH_VECTOR == XXH_SSE2 \
2904     || XXH_VECTOR == XXH_AVX2 || XXH_VECTOR == XXH_AVX512
2905 #  define XXH_SEC_ALIGN XXH_ACC_ALIGN
2906 #else
2907 #  define XXH_SEC_ALIGN 8
2908 #endif
2909 
2910 /*
2911  * UGLY HACK:
2912  * GCC usually generates the best code with -O3 for xxHash.
2913  *
2914  * However, when targeting AVX2, it is overzealous in its unrolling resulting
2915  * in code roughly 3/4 the speed of Clang.
2916  *
2917  * There are other issues, such as GCC splitting _mm256_loadu_si256 into
2918  * _mm_loadu_si128 + _mm256_inserti128_si256. This is an optimization which
2919  * only applies to Sandy and Ivy Bridge... which don't even support AVX2.
2920  *
2921  * That is why when compiling the AVX2 version, it is recommended to use either
2922  *   -O2 -mavx2 -march=haswell
2923  * or
2924  *   -O2 -mavx2 -mno-avx256-split-unaligned-load
2925  * for decent performance, or to use Clang instead.
2926  *
2927  * Fortunately, we can control the first one with a pragma that forces GCC into
2928  * -O2, but the other one we can't control without "failed to inline always
2929  * inline function due to target mismatch" warnings.
2930  */
2931 #if XXH_VECTOR == XXH_AVX2 /* AVX2 */ \
2932   && defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
2933   && defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) /* respect -O0 and -Os */
2934 #  pragma GCC push_options
2935 #  pragma GCC optimize("-O2")
2936 #endif
2937 
2938 
2939 #if XXH_VECTOR == XXH_NEON
2940 /*
2941  * NEON's setup for vmlal_u32 is a little more complicated than it is on
2942  * SSE2, AVX2, and VSX.
2943  *
2944  * While PMULUDQ and VMULEUW both perform a mask, VMLAL.U32 performs an upcast.
2945  *
2946  * To do the same operation, the 128-bit 'Q' register needs to be split into
2947  * two 64-bit 'D' registers, performing this operation::
2948  *
2949  *   [                a                 |                 b                ]
2950  *            |              '---------. .--------'                |
2951  *            |                         x                          |
2952  *            |              .---------' '--------.                |
2953  *   [ a & 0xFFFFFFFF | b & 0xFFFFFFFF ],[    a >> 32     |     b >> 32    ]
2954  *
2955  * Due to significant changes in aarch64, the fastest method for aarch64 is
2956  * completely different than the fastest method for ARMv7-A.
2957  *
2958  * ARMv7-A treats D registers as unions overlaying Q registers, so modifying
2959  * D11 will modify the high half of Q5. This is similar to how modifying AH
2960  * will only affect bits 8-15 of AX on x86.
2961  *
2962  * VZIP takes two registers, and puts even lanes in one register and odd lanes
2963  * in the other.
2964  *
2965  * On ARMv7-A, this strangely modifies both parameters in place instead of
2966  * taking the usual 3-operand form.
2967  *
2968  * Therefore, if we want to do this, we can simply use a D-form VZIP.32 on the
2969  * lower and upper halves of the Q register to end up with the high and low
2970  * halves where we want - all in one instruction.
2971  *
2972  *   vzip.32   d10, d11       @ d10 = { d10[0], d11[0] }; d11 = { d10[1], d11[1] }
2973  *
2974  * Unfortunately we need inline assembly for this: Instructions modifying two
2975  * registers at once is not possible in GCC or Clang's IR, and they have to
2976  * create a copy.
2977  *
2978  * aarch64 requires a different approach.
2979  *
2980  * In order to make it easier to write a decent compiler for aarch64, many
2981  * quirks were removed, such as conditional execution.
2982  *
2983  * NEON was also affected by this.
2984  *
2985  * aarch64 cannot access the high bits of a Q-form register, and writes to a
2986  * D-form register zero the high bits, similar to how writes to W-form scalar
2987  * registers (or DWORD registers on x86_64) work.
2988  *
2989  * The formerly free vget_high intrinsics now require a vext (with a few
2990  * exceptions)
2991  *
2992  * Additionally, VZIP was replaced by ZIP1 and ZIP2, which are the equivalent
2993  * of PUNPCKL* and PUNPCKH* in SSE, respectively, in order to only modify one
2994  * operand.
2995  *
2996  * The equivalent of the VZIP.32 on the lower and upper halves would be this
2997  * mess:
2998  *
2999  *   ext     v2.4s, v0.4s, v0.4s, #2 // v2 = { v0[2], v0[3], v0[0], v0[1] }
3000  *   zip1    v1.2s, v0.2s, v2.2s     // v1 = { v0[0], v2[0] }
3001  *   zip2    v0.2s, v0.2s, v1.2s     // v0 = { v0[1], v2[1] }
3002  *
3003  * Instead, we use a literal downcast, vmovn_u64 (XTN), and vshrn_n_u64 (SHRN):
3004  *
3005  *   shrn    v1.2s, v0.2d, #32  // v1 = (uint32x2_t)(v0 >> 32);
3006  *   xtn     v0.2s, v0.2d       // v0 = (uint32x2_t)(v0 & 0xFFFFFFFF);
3007  *
3008  * This is available on ARMv7-A, but is less efficient than a single VZIP.32.
3009  */
3010 
3011 /*!
3012  * Function-like macro:
3013  * void XXH_SPLIT_IN_PLACE(uint64x2_t &in, uint32x2_t &outLo, uint32x2_t &outHi)
3014  * {
3015  *     outLo = (uint32x2_t)(in & 0xFFFFFFFF);
3016  *     outHi = (uint32x2_t)(in >> 32);
3017  *     in = UNDEFINED;
3018  * }
3019  */
3020 # if !defined(XXH_NO_VZIP_HACK) /* define to disable */ \
3021    && defined(__GNUC__) \
3022    && !defined(__aarch64__) && !defined(__arm64__) && !defined(_M_ARM64)
3023 #  define XXH_SPLIT_IN_PLACE(in, outLo, outHi)                                              \
3024     do {                                                                                    \
3025       /* Undocumented GCC/Clang operand modifier: %e0 = lower D half, %f0 = upper D half */ \
3026       /* https://github.com/gcc-mirror/gcc/blob/38cf91e5/gcc/config/arm/arm.c#L22486 */     \
3027       /* https://github.com/llvm-mirror/llvm/blob/2c4ca683/lib/Target/ARM/ARMAsmPrinter.cpp#L399 */ \
3028       __asm__("vzip.32  %e0, %f0" : "+w" (in));                                             \
3029       (outLo) = vget_low_u32 (vreinterpretq_u32_u64(in));                                   \
3030       (outHi) = vget_high_u32(vreinterpretq_u32_u64(in));                                   \
3031    } while (0)
3032 # else
3033 #  define XXH_SPLIT_IN_PLACE(in, outLo, outHi)                                            \
3034     do {                                                                                  \
3035       (outLo) = vmovn_u64    (in);                                                        \
3036       (outHi) = vshrn_n_u64  ((in), 32);                                                  \
3037     } while (0)
3038 # endif
3039 #endif  /* XXH_VECTOR == XXH_NEON */
3040 
3041 /*
3042  * VSX and Z Vector helpers.
3043  *
3044  * This is very messy, and any pull requests to clean this up are welcome.
3045  *
3046  * There are a lot of problems with supporting VSX and s390x, due to
3047  * inconsistent intrinsics, spotty coverage, and multiple endiannesses.
3048  */
3049 #if XXH_VECTOR == XXH_VSX
3050 #  if defined(__s390x__)
3051 #    include <s390intrin.h>
3052 #  else
3053 /* gcc's altivec.h can have the unwanted consequence to unconditionally
3054  * #define bool, vector, and pixel keywords,
3055  * with bad consequences for programs already using these keywords for other purposes.
3056  * The paragraph defining these macros is skipped when __APPLE_ALTIVEC__ is defined.
3057  * __APPLE_ALTIVEC__ is _generally_ defined automatically by the compiler,
3058  * but it seems that, in some cases, it isn't.
3059  * Force the build macro to be defined, so that keywords are not altered.
3060  */
3061 #    if defined(__GNUC__) && !defined(__APPLE_ALTIVEC__)
3062 #      define __APPLE_ALTIVEC__
3063 #    endif
3064 #    include <altivec.h>
3065 #  endif
3066 
3067 typedef __vector unsigned long long xxh_u64x2;
3068 typedef __vector unsigned char xxh_u8x16;
3069 typedef __vector unsigned xxh_u32x4;
3070 
3071 # ifndef XXH_VSX_BE
3072 #  if defined(__BIG_ENDIAN__) \
3073   || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
3074 #    define XXH_VSX_BE 1
3075 #  elif defined(__VEC_ELEMENT_REG_ORDER__) && __VEC_ELEMENT_REG_ORDER__ == __ORDER_BIG_ENDIAN__
3076 #    warning "-maltivec=be is not recommended. Please use native endianness."
3077 #    define XXH_VSX_BE 1
3078 #  else
3079 #    define XXH_VSX_BE 0
3080 #  endif
3081 # endif /* !defined(XXH_VSX_BE) */
3082 
3083 # if XXH_VSX_BE
3084 #  if defined(__POWER9_VECTOR__) || (defined(__clang__) && defined(__s390x__))
3085 #    define XXH_vec_revb vec_revb
3086 #  else
3087 /*!
3088  * A polyfill for POWER9's vec_revb().
3089  */
XXH_vec_revb(xxh_u64x2 val)3090 XXH_FORCE_INLINE xxh_u64x2 XXH_vec_revb(xxh_u64x2 val)
3091 {
3092     xxh_u8x16 const vByteSwap = { 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
3093                                   0x0F, 0x0E, 0x0D, 0x0C, 0x0B, 0x0A, 0x09, 0x08 };
3094     return vec_perm(val, val, vByteSwap);
3095 }
3096 #  endif
3097 # endif /* XXH_VSX_BE */
3098 
3099 /*!
3100  * Performs an unaligned vector load and byte swaps it on big endian.
3101  */
XXH_vec_loadu(const void * ptr)3102 XXH_FORCE_INLINE xxh_u64x2 XXH_vec_loadu(const void *ptr)
3103 {
3104     xxh_u64x2 ret;
3105     XXH_memcpy(&ret, ptr, sizeof(xxh_u64x2));
3106 # if XXH_VSX_BE
3107     ret = XXH_vec_revb(ret);
3108 # endif
3109     return ret;
3110 }
3111 
3112 /*
3113  * vec_mulo and vec_mule are very problematic intrinsics on PowerPC
3114  *
3115  * These intrinsics weren't added until GCC 8, despite existing for a while,
3116  * and they are endian dependent. Also, their meaning swap depending on version.
3117  * */
3118 # if defined(__s390x__)
3119  /* s390x is always big endian, no issue on this platform */
3120 #  define XXH_vec_mulo vec_mulo
3121 #  define XXH_vec_mule vec_mule
3122 # elif defined(__clang__) && XXH_HAS_BUILTIN(__builtin_altivec_vmuleuw)
3123 /* Clang has a better way to control this, we can just use the builtin which doesn't swap. */
3124 #  define XXH_vec_mulo __builtin_altivec_vmulouw
3125 #  define XXH_vec_mule __builtin_altivec_vmuleuw
3126 # else
3127 /* gcc needs inline assembly */
3128 /* Adapted from https://github.com/google/highwayhash/blob/master/highwayhash/hh_vsx.h. */
XXH_vec_mulo(xxh_u32x4 a,xxh_u32x4 b)3129 XXH_FORCE_INLINE xxh_u64x2 XXH_vec_mulo(xxh_u32x4 a, xxh_u32x4 b)
3130 {
3131     xxh_u64x2 result;
3132     __asm__("vmulouw %0, %1, %2" : "=v" (result) : "v" (a), "v" (b));
3133     return result;
3134 }
XXH_vec_mule(xxh_u32x4 a,xxh_u32x4 b)3135 XXH_FORCE_INLINE xxh_u64x2 XXH_vec_mule(xxh_u32x4 a, xxh_u32x4 b)
3136 {
3137     xxh_u64x2 result;
3138     __asm__("vmuleuw %0, %1, %2" : "=v" (result) : "v" (a), "v" (b));
3139     return result;
3140 }
3141 # endif /* XXH_vec_mulo, XXH_vec_mule */
3142 #endif /* XXH_VECTOR == XXH_VSX */
3143 
3144 
3145 /* prefetch
3146  * can be disabled, by declaring XXH_NO_PREFETCH build macro */
3147 #if defined(XXH_NO_PREFETCH)
3148 #  define XXH_PREFETCH(ptr)  (void)(ptr)  /* disabled */
3149 #else
3150 #  if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86))  /* _mm_prefetch() not defined outside of x86/x64 */
3151 #    include <mmintrin.h>   /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
3152 #    define XXH_PREFETCH(ptr)  _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
3153 #  elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
3154 #    define XXH_PREFETCH(ptr)  __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */)
3155 #  else
3156 #    define XXH_PREFETCH(ptr) (void)(ptr)  /* disabled */
3157 #  endif
3158 #endif  /* XXH_NO_PREFETCH */
3159 
3160 
3161 /* ==========================================
3162  * XXH3 default settings
3163  * ========================================== */
3164 
3165 #define XXH_SECRET_DEFAULT_SIZE 192   /* minimum XXH3_SECRET_SIZE_MIN */
3166 
3167 #if (XXH_SECRET_DEFAULT_SIZE < XXH3_SECRET_SIZE_MIN)
3168 #  error "default keyset is not large enough"
3169 #endif
3170 
3171 /*! Pseudorandom secret taken directly from FARSH. */
3172 XXH_ALIGN(64) static const xxh_u8 XXH3_kSecret[XXH_SECRET_DEFAULT_SIZE] = {
3173     0xb8, 0xfe, 0x6c, 0x39, 0x23, 0xa4, 0x4b, 0xbe, 0x7c, 0x01, 0x81, 0x2c, 0xf7, 0x21, 0xad, 0x1c,
3174     0xde, 0xd4, 0x6d, 0xe9, 0x83, 0x90, 0x97, 0xdb, 0x72, 0x40, 0xa4, 0xa4, 0xb7, 0xb3, 0x67, 0x1f,
3175     0xcb, 0x79, 0xe6, 0x4e, 0xcc, 0xc0, 0xe5, 0x78, 0x82, 0x5a, 0xd0, 0x7d, 0xcc, 0xff, 0x72, 0x21,
3176     0xb8, 0x08, 0x46, 0x74, 0xf7, 0x43, 0x24, 0x8e, 0xe0, 0x35, 0x90, 0xe6, 0x81, 0x3a, 0x26, 0x4c,
3177     0x3c, 0x28, 0x52, 0xbb, 0x91, 0xc3, 0x00, 0xcb, 0x88, 0xd0, 0x65, 0x8b, 0x1b, 0x53, 0x2e, 0xa3,
3178     0x71, 0x64, 0x48, 0x97, 0xa2, 0x0d, 0xf9, 0x4e, 0x38, 0x19, 0xef, 0x46, 0xa9, 0xde, 0xac, 0xd8,
3179     0xa8, 0xfa, 0x76, 0x3f, 0xe3, 0x9c, 0x34, 0x3f, 0xf9, 0xdc, 0xbb, 0xc7, 0xc7, 0x0b, 0x4f, 0x1d,
3180     0x8a, 0x51, 0xe0, 0x4b, 0xcd, 0xb4, 0x59, 0x31, 0xc8, 0x9f, 0x7e, 0xc9, 0xd9, 0x78, 0x73, 0x64,
3181     0xea, 0xc5, 0xac, 0x83, 0x34, 0xd3, 0xeb, 0xc3, 0xc5, 0x81, 0xa0, 0xff, 0xfa, 0x13, 0x63, 0xeb,
3182     0x17, 0x0d, 0xdd, 0x51, 0xb7, 0xf0, 0xda, 0x49, 0xd3, 0x16, 0x55, 0x26, 0x29, 0xd4, 0x68, 0x9e,
3183     0x2b, 0x16, 0xbe, 0x58, 0x7d, 0x47, 0xa1, 0xfc, 0x8f, 0xf8, 0xb8, 0xd1, 0x7a, 0xd0, 0x31, 0xce,
3184     0x45, 0xcb, 0x3a, 0x8f, 0x95, 0x16, 0x04, 0x28, 0xaf, 0xd7, 0xfb, 0xca, 0xbb, 0x4b, 0x40, 0x7e,
3185 };
3186 
3187 
3188 #ifdef XXH_OLD_NAMES
3189 #  define kSecret XXH3_kSecret
3190 #endif
3191 
3192 #ifdef XXH_DOXYGEN
3193 /*!
3194  * @brief Calculates a 32-bit to 64-bit long multiply.
3195  *
3196  * Implemented as a macro.
3197  *
3198  * Wraps `__emulu` on MSVC x86 because it tends to call `__allmul` when it doesn't
3199  * need to (but it shouldn't need to anyways, it is about 7 instructions to do
3200  * a 64x64 multiply...). Since we know that this will _always_ emit `MULL`, we
3201  * use that instead of the normal method.
3202  *
3203  * If you are compiling for platforms like Thumb-1 and don't have a better option,
3204  * you may also want to write your own long multiply routine here.
3205  *
3206  * @param x, y Numbers to be multiplied
3207  * @return 64-bit product of the low 32 bits of @p x and @p y.
3208  */
3209 XXH_FORCE_INLINE xxh_u64
XXH_mult32to64(xxh_u64 x,xxh_u64 y)3210 XXH_mult32to64(xxh_u64 x, xxh_u64 y)
3211 {
3212    return (x & 0xFFFFFFFF) * (y & 0xFFFFFFFF);
3213 }
3214 #elif defined(_MSC_VER) && defined(_M_IX86)
3215 #    include <intrin.h>
3216 #    define XXH_mult32to64(x, y) __emulu((unsigned)(x), (unsigned)(y))
3217 #else
3218 /*
3219  * Downcast + upcast is usually better than masking on older compilers like
3220  * GCC 4.2 (especially 32-bit ones), all without affecting newer compilers.
3221  *
3222  * The other method, (x & 0xFFFFFFFF) * (y & 0xFFFFFFFF), will AND both operands
3223  * and perform a full 64x64 multiply -- entirely redundant on 32-bit.
3224  */
3225 #    define XXH_mult32to64(x, y) ((xxh_u64)(xxh_u32)(x) * (xxh_u64)(xxh_u32)(y))
3226 #endif
3227 
3228 /*!
3229  * @brief Calculates a 64->128-bit long multiply.
3230  *
3231  * Uses `__uint128_t` and `_umul128` if available, otherwise uses a scalar
3232  * version.
3233  *
3234  * @param lhs , rhs The 64-bit integers to be multiplied
3235  * @return The 128-bit result represented in an @ref XXH128_hash_t.
3236  */
3237 static XXH128_hash_t
XXH_mult64to128(xxh_u64 lhs,xxh_u64 rhs)3238 XXH_mult64to128(xxh_u64 lhs, xxh_u64 rhs)
3239 {
3240     /*
3241      * GCC/Clang __uint128_t method.
3242      *
3243      * On most 64-bit targets, GCC and Clang define a __uint128_t type.
3244      * This is usually the best way as it usually uses a native long 64-bit
3245      * multiply, such as MULQ on x86_64 or MUL + UMULH on aarch64.
3246      *
3247      * Usually.
3248      *
3249      * Despite being a 32-bit platform, Clang (and emscripten) define this type
3250      * despite not having the arithmetic for it. This results in a laggy
3251      * compiler builtin call which calculates a full 128-bit multiply.
3252      * In that case it is best to use the portable one.
3253      * https://github.com/Cyan4973/xxHash/issues/211#issuecomment-515575677
3254      */
3255 #if defined(__GNUC__) && !defined(__wasm__) \
3256     && defined(__SIZEOF_INT128__) \
3257     || (defined(_INTEGRAL_MAX_BITS) && _INTEGRAL_MAX_BITS >= 128)
3258 
3259     __uint128_t const product = (__uint128_t)lhs * (__uint128_t)rhs;
3260     XXH128_hash_t r128;
3261     r128.low64  = (xxh_u64)(product);
3262     r128.high64 = (xxh_u64)(product >> 64);
3263     return r128;
3264 
3265     /*
3266      * MSVC for x64's _umul128 method.
3267      *
3268      * xxh_u64 _umul128(xxh_u64 Multiplier, xxh_u64 Multiplicand, xxh_u64 *HighProduct);
3269      *
3270      * This compiles to single operand MUL on x64.
3271      */
3272 #elif defined(_M_X64) || defined(_M_IA64)
3273 
3274 #ifndef _MSC_VER
3275 #   pragma intrinsic(_umul128)
3276 #endif
3277     xxh_u64 product_high;
3278     xxh_u64 const product_low = _umul128(lhs, rhs, &product_high);
3279     XXH128_hash_t r128;
3280     r128.low64  = product_low;
3281     r128.high64 = product_high;
3282     return r128;
3283 
3284     /*
3285      * MSVC for ARM64's __umulh method.
3286      *
3287      * This compiles to the same MUL + UMULH as GCC/Clang's __uint128_t method.
3288      */
3289 #elif defined(_M_ARM64)
3290 
3291 #ifndef _MSC_VER
3292 #   pragma intrinsic(__umulh)
3293 #endif
3294     XXH128_hash_t r128;
3295     r128.low64  = lhs * rhs;
3296     r128.high64 = __umulh(lhs, rhs);
3297     return r128;
3298 
3299 #else
3300     /*
3301      * Portable scalar method. Optimized for 32-bit and 64-bit ALUs.
3302      *
3303      * This is a fast and simple grade school multiply, which is shown below
3304      * with base 10 arithmetic instead of base 0x100000000.
3305      *
3306      *           9 3 // D2 lhs = 93
3307      *         x 7 5 // D2 rhs = 75
3308      *     ----------
3309      *           1 5 // D2 lo_lo = (93 % 10) * (75 % 10) = 15
3310      *         4 5 | // D2 hi_lo = (93 / 10) * (75 % 10) = 45
3311      *         2 1 | // D2 lo_hi = (93 % 10) * (75 / 10) = 21
3312      *     + 6 3 | | // D2 hi_hi = (93 / 10) * (75 / 10) = 63
3313      *     ---------
3314      *         2 7 | // D2 cross = (15 / 10) + (45 % 10) + 21 = 27
3315      *     + 6 7 | | // D2 upper = (27 / 10) + (45 / 10) + 63 = 67
3316      *     ---------
3317      *       6 9 7 5 // D4 res = (27 * 10) + (15 % 10) + (67 * 100) = 6975
3318      *
3319      * The reasons for adding the products like this are:
3320      *  1. It avoids manual carry tracking. Just like how
3321      *     (9 * 9) + 9 + 9 = 99, the same applies with this for UINT64_MAX.
3322      *     This avoids a lot of complexity.
3323      *
3324      *  2. It hints for, and on Clang, compiles to, the powerful UMAAL
3325      *     instruction available in ARM's Digital Signal Processing extension
3326      *     in 32-bit ARMv6 and later, which is shown below:
3327      *
3328      *         void UMAAL(xxh_u32 *RdLo, xxh_u32 *RdHi, xxh_u32 Rn, xxh_u32 Rm)
3329      *         {
3330      *             xxh_u64 product = (xxh_u64)*RdLo * (xxh_u64)*RdHi + Rn + Rm;
3331      *             *RdLo = (xxh_u32)(product & 0xFFFFFFFF);
3332      *             *RdHi = (xxh_u32)(product >> 32);
3333      *         }
3334      *
3335      *     This instruction was designed for efficient long multiplication, and
3336      *     allows this to be calculated in only 4 instructions at speeds
3337      *     comparable to some 64-bit ALUs.
3338      *
3339      *  3. It isn't terrible on other platforms. Usually this will be a couple
3340      *     of 32-bit ADD/ADCs.
3341      */
3342 
3343     /* First calculate all of the cross products. */
3344     xxh_u64 const lo_lo = XXH_mult32to64(lhs & 0xFFFFFFFF, rhs & 0xFFFFFFFF);
3345     xxh_u64 const hi_lo = XXH_mult32to64(lhs >> 32,        rhs & 0xFFFFFFFF);
3346     xxh_u64 const lo_hi = XXH_mult32to64(lhs & 0xFFFFFFFF, rhs >> 32);
3347     xxh_u64 const hi_hi = XXH_mult32to64(lhs >> 32,        rhs >> 32);
3348 
3349     /* Now add the products together. These will never overflow. */
3350     xxh_u64 const cross = (lo_lo >> 32) + (hi_lo & 0xFFFFFFFF) + lo_hi;
3351     xxh_u64 const upper = (hi_lo >> 32) + (cross >> 32)        + hi_hi;
3352     xxh_u64 const lower = (cross << 32) | (lo_lo & 0xFFFFFFFF);
3353 
3354     XXH128_hash_t r128;
3355     r128.low64  = lower;
3356     r128.high64 = upper;
3357     return r128;
3358 #endif
3359 }
3360 
3361 /*!
3362  * @brief Calculates a 64-bit to 128-bit multiply, then XOR folds it.
3363  *
3364  * The reason for the separate function is to prevent passing too many structs
3365  * around by value. This will hopefully inline the multiply, but we don't force it.
3366  *
3367  * @param lhs , rhs The 64-bit integers to multiply
3368  * @return The low 64 bits of the product XOR'd by the high 64 bits.
3369  * @see XXH_mult64to128()
3370  */
3371 static xxh_u64
XXH3_mul128_fold64(xxh_u64 lhs,xxh_u64 rhs)3372 XXH3_mul128_fold64(xxh_u64 lhs, xxh_u64 rhs)
3373 {
3374     XXH128_hash_t product = XXH_mult64to128(lhs, rhs);
3375     return product.low64 ^ product.high64;
3376 }
3377 
3378 /*! Seems to produce slightly better code on GCC for some reason. */
XXH_xorshift64(xxh_u64 v64,int shift)3379 XXH_FORCE_INLINE xxh_u64 XXH_xorshift64(xxh_u64 v64, int shift)
3380 {
3381     XXH_ASSERT(0 <= shift && shift < 64);
3382     return v64 ^ (v64 >> shift);
3383 }
3384 
3385 /*
3386  * This is a fast avalanche stage,
3387  * suitable when input bits are already partially mixed
3388  */
XXH3_avalanche(xxh_u64 h64)3389 static XXH64_hash_t XXH3_avalanche(xxh_u64 h64)
3390 {
3391     h64 = XXH_xorshift64(h64, 37);
3392     h64 *= 0x165667919E3779F9ULL;
3393     h64 = XXH_xorshift64(h64, 32);
3394     return h64;
3395 }
3396 
3397 /*
3398  * This is a stronger avalanche,
3399  * inspired by Pelle Evensen's rrmxmx
3400  * preferable when input has not been previously mixed
3401  */
XXH3_rrmxmx(xxh_u64 h64,xxh_u64 len)3402 static XXH64_hash_t XXH3_rrmxmx(xxh_u64 h64, xxh_u64 len)
3403 {
3404     /* this mix is inspired by Pelle Evensen's rrmxmx */
3405     h64 ^= XXH_rotl64(h64, 49) ^ XXH_rotl64(h64, 24);
3406     h64 *= 0x9FB21C651E98DF25ULL;
3407     h64 ^= (h64 >> 35) + len ;
3408     h64 *= 0x9FB21C651E98DF25ULL;
3409     return XXH_xorshift64(h64, 28);
3410 }
3411 
3412 
3413 /* ==========================================
3414  * Short keys
3415  * ==========================================
3416  * One of the shortcomings of XXH32 and XXH64 was that their performance was
3417  * sub-optimal on short lengths. It used an iterative algorithm which strongly
3418  * favored lengths that were a multiple of 4 or 8.
3419  *
3420  * Instead of iterating over individual inputs, we use a set of single shot
3421  * functions which piece together a range of lengths and operate in constant time.
3422  *
3423  * Additionally, the number of multiplies has been significantly reduced. This
3424  * reduces latency, especially when emulating 64-bit multiplies on 32-bit.
3425  *
3426  * Depending on the platform, this may or may not be faster than XXH32, but it
3427  * is almost guaranteed to be faster than XXH64.
3428  */
3429 
3430 /*
3431  * At very short lengths, there isn't enough input to fully hide secrets, or use
3432  * the entire secret.
3433  *
3434  * There is also only a limited amount of mixing we can do before significantly
3435  * impacting performance.
3436  *
3437  * Therefore, we use different sections of the secret and always mix two secret
3438  * samples with an XOR. This should have no effect on performance on the
3439  * seedless or withSeed variants because everything _should_ be constant folded
3440  * by modern compilers.
3441  *
3442  * The XOR mixing hides individual parts of the secret and increases entropy.
3443  *
3444  * This adds an extra layer of strength for custom secrets.
3445  */
3446 XXH_FORCE_INLINE XXH64_hash_t
XXH3_len_1to3_64b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)3447 XXH3_len_1to3_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3448 {
3449     XXH_ASSERT(input != NULL);
3450     XXH_ASSERT(1 <= len && len <= 3);
3451     XXH_ASSERT(secret != NULL);
3452     /*
3453      * len = 1: combined = { input[0], 0x01, input[0], input[0] }
3454      * len = 2: combined = { input[1], 0x02, input[0], input[1] }
3455      * len = 3: combined = { input[2], 0x03, input[0], input[1] }
3456      */
3457     {   xxh_u8  const c1 = input[0];
3458         xxh_u8  const c2 = input[len >> 1];
3459         xxh_u8  const c3 = input[len - 1];
3460         xxh_u32 const combined = ((xxh_u32)c1 << 16) | ((xxh_u32)c2  << 24)
3461                                | ((xxh_u32)c3 <<  0) | ((xxh_u32)len << 8);
3462         xxh_u64 const bitflip = (XXH_readLE32(secret) ^ XXH_readLE32(secret+4)) + seed;
3463         xxh_u64 const keyed = (xxh_u64)combined ^ bitflip;
3464         return XXH64_avalanche(keyed);
3465     }
3466 }
3467 
3468 XXH_FORCE_INLINE XXH64_hash_t
XXH3_len_4to8_64b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)3469 XXH3_len_4to8_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3470 {
3471     XXH_ASSERT(input != NULL);
3472     XXH_ASSERT(secret != NULL);
3473     XXH_ASSERT(4 <= len && len <= 8);
3474     seed ^= (xxh_u64)XXH_swap32((xxh_u32)seed) << 32;
3475     {   xxh_u32 const input1 = XXH_readLE32(input);
3476         xxh_u32 const input2 = XXH_readLE32(input + len - 4);
3477         xxh_u64 const bitflip = (XXH_readLE64(secret+8) ^ XXH_readLE64(secret+16)) - seed;
3478         xxh_u64 const input64 = input2 + (((xxh_u64)input1) << 32);
3479         xxh_u64 const keyed = input64 ^ bitflip;
3480         return XXH3_rrmxmx(keyed, len);
3481     }
3482 }
3483 
3484 XXH_FORCE_INLINE XXH64_hash_t
XXH3_len_9to16_64b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)3485 XXH3_len_9to16_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3486 {
3487     XXH_ASSERT(input != NULL);
3488     XXH_ASSERT(secret != NULL);
3489     XXH_ASSERT(9 <= len && len <= 16);
3490     {   xxh_u64 const bitflip1 = (XXH_readLE64(secret+24) ^ XXH_readLE64(secret+32)) + seed;
3491         xxh_u64 const bitflip2 = (XXH_readLE64(secret+40) ^ XXH_readLE64(secret+48)) - seed;
3492         xxh_u64 const input_lo = XXH_readLE64(input)           ^ bitflip1;
3493         xxh_u64 const input_hi = XXH_readLE64(input + len - 8) ^ bitflip2;
3494         xxh_u64 const acc = len
3495                           + XXH_swap64(input_lo) + input_hi
3496                           + XXH3_mul128_fold64(input_lo, input_hi);
3497         return XXH3_avalanche(acc);
3498     }
3499 }
3500 
3501 XXH_FORCE_INLINE XXH64_hash_t
XXH3_len_0to16_64b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)3502 XXH3_len_0to16_64b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
3503 {
3504     XXH_ASSERT(len <= 16);
3505     {   if (XXH_likely(len >  8)) return XXH3_len_9to16_64b(input, len, secret, seed);
3506         if (XXH_likely(len >= 4)) return XXH3_len_4to8_64b(input, len, secret, seed);
3507         if (len) return XXH3_len_1to3_64b(input, len, secret, seed);
3508         return XXH64_avalanche(seed ^ (XXH_readLE64(secret+56) ^ XXH_readLE64(secret+64)));
3509     }
3510 }
3511 
3512 /*
3513  * DISCLAIMER: There are known *seed-dependent* multicollisions here due to
3514  * multiplication by zero, affecting hashes of lengths 17 to 240.
3515  *
3516  * However, they are very unlikely.
3517  *
3518  * Keep this in mind when using the unseeded XXH3_64bits() variant: As with all
3519  * unseeded non-cryptographic hashes, it does not attempt to defend itself
3520  * against specially crafted inputs, only random inputs.
3521  *
3522  * Compared to classic UMAC where a 1 in 2^31 chance of 4 consecutive bytes
3523  * cancelling out the secret is taken an arbitrary number of times (addressed
3524  * in XXH3_accumulate_512), this collision is very unlikely with random inputs
3525  * and/or proper seeding:
3526  *
3527  * This only has a 1 in 2^63 chance of 8 consecutive bytes cancelling out, in a
3528  * function that is only called up to 16 times per hash with up to 240 bytes of
3529  * input.
3530  *
3531  * This is not too bad for a non-cryptographic hash function, especially with
3532  * only 64 bit outputs.
3533  *
3534  * The 128-bit variant (which trades some speed for strength) is NOT affected
3535  * by this, although it is always a good idea to use a proper seed if you care
3536  * about strength.
3537  */
XXH3_mix16B(const xxh_u8 * XXH_RESTRICT input,const xxh_u8 * XXH_RESTRICT secret,xxh_u64 seed64)3538 XXH_FORCE_INLINE xxh_u64 XXH3_mix16B(const xxh_u8* XXH_RESTRICT input,
3539                                      const xxh_u8* XXH_RESTRICT secret, xxh_u64 seed64)
3540 {
3541 #if defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
3542   && defined(__i386__) && defined(__SSE2__)  /* x86 + SSE2 */ \
3543   && !defined(XXH_ENABLE_AUTOVECTORIZE)      /* Define to disable like XXH32 hack */
3544     /*
3545      * UGLY HACK:
3546      * GCC for x86 tends to autovectorize the 128-bit multiply, resulting in
3547      * slower code.
3548      *
3549      * By forcing seed64 into a register, we disrupt the cost model and
3550      * cause it to scalarize. See `XXH32_round()`
3551      *
3552      * FIXME: Clang's output is still _much_ faster -- On an AMD Ryzen 3600,
3553      * XXH3_64bits @ len=240 runs at 4.6 GB/s with Clang 9, but 3.3 GB/s on
3554      * GCC 9.2, despite both emitting scalar code.
3555      *
3556      * GCC generates much better scalar code than Clang for the rest of XXH3,
3557      * which is why finding a more optimal codepath is an interest.
3558      */
3559     XXH_COMPILER_GUARD(seed64);
3560 #endif
3561     {   xxh_u64 const input_lo = XXH_readLE64(input);
3562         xxh_u64 const input_hi = XXH_readLE64(input+8);
3563         return XXH3_mul128_fold64(
3564             input_lo ^ (XXH_readLE64(secret)   + seed64),
3565             input_hi ^ (XXH_readLE64(secret+8) - seed64)
3566         );
3567     }
3568 }
3569 
3570 /* For mid range keys, XXH3 uses a Mum-hash variant. */
3571 XXH_FORCE_INLINE XXH64_hash_t
XXH3_len_17to128_64b(const xxh_u8 * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH64_hash_t seed)3572 XXH3_len_17to128_64b(const xxh_u8* XXH_RESTRICT input, size_t len,
3573                      const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
3574                      XXH64_hash_t seed)
3575 {
3576     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
3577     XXH_ASSERT(16 < len && len <= 128);
3578 
3579     {   xxh_u64 acc = len * XXH_PRIME64_1;
3580         if (len > 32) {
3581             if (len > 64) {
3582                 if (len > 96) {
3583                     acc += XXH3_mix16B(input+48, secret+96, seed);
3584                     acc += XXH3_mix16B(input+len-64, secret+112, seed);
3585                 }
3586                 acc += XXH3_mix16B(input+32, secret+64, seed);
3587                 acc += XXH3_mix16B(input+len-48, secret+80, seed);
3588             }
3589             acc += XXH3_mix16B(input+16, secret+32, seed);
3590             acc += XXH3_mix16B(input+len-32, secret+48, seed);
3591         }
3592         acc += XXH3_mix16B(input+0, secret+0, seed);
3593         acc += XXH3_mix16B(input+len-16, secret+16, seed);
3594 
3595         return XXH3_avalanche(acc);
3596     }
3597 }
3598 
3599 #define XXH3_MIDSIZE_MAX 240
3600 
3601 XXH_NO_INLINE XXH64_hash_t
XXH3_len_129to240_64b(const xxh_u8 * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH64_hash_t seed)3602 XXH3_len_129to240_64b(const xxh_u8* XXH_RESTRICT input, size_t len,
3603                       const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
3604                       XXH64_hash_t seed)
3605 {
3606     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
3607     XXH_ASSERT(128 < len && len <= XXH3_MIDSIZE_MAX);
3608 
3609     #define XXH3_MIDSIZE_STARTOFFSET 3
3610     #define XXH3_MIDSIZE_LASTOFFSET  17
3611 
3612     {   xxh_u64 acc = len * XXH_PRIME64_1;
3613         int const nbRounds = (int)len / 16;
3614         int i;
3615         for (i=0; i<8; i++) {
3616             acc += XXH3_mix16B(input+(16*i), secret+(16*i), seed);
3617         }
3618         acc = XXH3_avalanche(acc);
3619         XXH_ASSERT(nbRounds >= 8);
3620 #if defined(__clang__)                                /* Clang */ \
3621     && (defined(__ARM_NEON) || defined(__ARM_NEON__)) /* NEON */ \
3622     && !defined(XXH_ENABLE_AUTOVECTORIZE)             /* Define to disable */
3623         /*
3624          * UGLY HACK:
3625          * Clang for ARMv7-A tries to vectorize this loop, similar to GCC x86.
3626          * In everywhere else, it uses scalar code.
3627          *
3628          * For 64->128-bit multiplies, even if the NEON was 100% optimal, it
3629          * would still be slower than UMAAL (see XXH_mult64to128).
3630          *
3631          * Unfortunately, Clang doesn't handle the long multiplies properly and
3632          * converts them to the nonexistent "vmulq_u64" intrinsic, which is then
3633          * scalarized into an ugly mess of VMOV.32 instructions.
3634          *
3635          * This mess is difficult to avoid without turning autovectorization
3636          * off completely, but they are usually relatively minor and/or not
3637          * worth it to fix.
3638          *
3639          * This loop is the easiest to fix, as unlike XXH32, this pragma
3640          * _actually works_ because it is a loop vectorization instead of an
3641          * SLP vectorization.
3642          */
3643         #pragma clang loop vectorize(disable)
3644 #endif
3645         for (i=8 ; i < nbRounds; i++) {
3646             acc += XXH3_mix16B(input+(16*i), secret+(16*(i-8)) + XXH3_MIDSIZE_STARTOFFSET, seed);
3647         }
3648         /* last bytes */
3649         acc += XXH3_mix16B(input + len - 16, secret + XXH3_SECRET_SIZE_MIN - XXH3_MIDSIZE_LASTOFFSET, seed);
3650         return XXH3_avalanche(acc);
3651     }
3652 }
3653 
3654 
3655 /* =======     Long Keys     ======= */
3656 
3657 #define XXH_STRIPE_LEN 64
3658 #define XXH_SECRET_CONSUME_RATE 8   /* nb of secret bytes consumed at each accumulation */
3659 #define XXH_ACC_NB (XXH_STRIPE_LEN / sizeof(xxh_u64))
3660 
3661 #ifdef XXH_OLD_NAMES
3662 #  define STRIPE_LEN XXH_STRIPE_LEN
3663 #  define ACC_NB XXH_ACC_NB
3664 #endif
3665 
XXH_writeLE64(void * dst,xxh_u64 v64)3666 XXH_FORCE_INLINE void XXH_writeLE64(void* dst, xxh_u64 v64)
3667 {
3668     if (!XXH_CPU_LITTLE_ENDIAN) v64 = XXH_swap64(v64);
3669     XXH_memcpy(dst, &v64, sizeof(v64));
3670 }
3671 
3672 /* Several intrinsic functions below are supposed to accept __int64 as argument,
3673  * as documented in https://software.intel.com/sites/landingpage/IntrinsicsGuide/ .
3674  * However, several environments do not define __int64 type,
3675  * requiring a workaround.
3676  */
3677 #if !defined (__VMS) \
3678   && (defined (__cplusplus) \
3679   || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
3680     typedef int64_t xxh_i64;
3681 #else
3682     /* the following type must have a width of 64-bit */
3683     typedef long long xxh_i64;
3684 #endif
3685 
3686 /*
3687  * XXH3_accumulate_512 is the tightest loop for long inputs, and it is the most optimized.
3688  *
3689  * It is a hardened version of UMAC, based off of FARSH's implementation.
3690  *
3691  * This was chosen because it adapts quite well to 32-bit, 64-bit, and SIMD
3692  * implementations, and it is ridiculously fast.
3693  *
3694  * We harden it by mixing the original input to the accumulators as well as the product.
3695  *
3696  * This means that in the (relatively likely) case of a multiply by zero, the
3697  * original input is preserved.
3698  *
3699  * On 128-bit inputs, we swap 64-bit pairs when we add the input to improve
3700  * cross-pollination, as otherwise the upper and lower halves would be
3701  * essentially independent.
3702  *
3703  * This doesn't matter on 64-bit hashes since they all get merged together in
3704  * the end, so we skip the extra step.
3705  *
3706  * Both XXH3_64bits and XXH3_128bits use this subroutine.
3707  */
3708 
3709 #if (XXH_VECTOR == XXH_AVX512) \
3710      || (defined(XXH_DISPATCH_AVX512) && XXH_DISPATCH_AVX512 != 0)
3711 
3712 #ifndef XXH_TARGET_AVX512
3713 # define XXH_TARGET_AVX512  /* disable attribute target */
3714 #endif
3715 
3716 XXH_FORCE_INLINE XXH_TARGET_AVX512 void
XXH3_accumulate_512_avx512(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)3717 XXH3_accumulate_512_avx512(void* XXH_RESTRICT acc,
3718                      const void* XXH_RESTRICT input,
3719                      const void* XXH_RESTRICT secret)
3720 {
3721     __m512i* const xacc = (__m512i *) acc;
3722     XXH_ASSERT((((size_t)acc) & 63) == 0);
3723     XXH_STATIC_ASSERT(XXH_STRIPE_LEN == sizeof(__m512i));
3724 
3725     {
3726         /* data_vec    = input[0]; */
3727         __m512i const data_vec    = _mm512_loadu_si512   (input);
3728         /* key_vec     = secret[0]; */
3729         __m512i const key_vec     = _mm512_loadu_si512   (secret);
3730         /* data_key    = data_vec ^ key_vec; */
3731         __m512i const data_key    = _mm512_xor_si512     (data_vec, key_vec);
3732         /* data_key_lo = data_key >> 32; */
3733         __m512i const data_key_lo = _mm512_shuffle_epi32 (data_key, (_MM_PERM_ENUM)_MM_SHUFFLE(0, 3, 0, 1));
3734         /* product     = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3735         __m512i const product     = _mm512_mul_epu32     (data_key, data_key_lo);
3736         /* xacc[0] += swap(data_vec); */
3737         __m512i const data_swap = _mm512_shuffle_epi32(data_vec, (_MM_PERM_ENUM)_MM_SHUFFLE(1, 0, 3, 2));
3738         __m512i const sum       = _mm512_add_epi64(*xacc, data_swap);
3739         /* xacc[0] += product; */
3740         *xacc = _mm512_add_epi64(product, sum);
3741     }
3742 }
3743 
3744 /*
3745  * XXH3_scrambleAcc: Scrambles the accumulators to improve mixing.
3746  *
3747  * Multiplication isn't perfect, as explained by Google in HighwayHash:
3748  *
3749  *  // Multiplication mixes/scrambles bytes 0-7 of the 64-bit result to
3750  *  // varying degrees. In descending order of goodness, bytes
3751  *  // 3 4 2 5 1 6 0 7 have quality 228 224 164 160 100 96 36 32.
3752  *  // As expected, the upper and lower bytes are much worse.
3753  *
3754  * Source: https://github.com/google/highwayhash/blob/0aaf66b/highwayhash/hh_avx2.h#L291
3755  *
3756  * Since our algorithm uses a pseudorandom secret to add some variance into the
3757  * mix, we don't need to (or want to) mix as often or as much as HighwayHash does.
3758  *
3759  * This isn't as tight as XXH3_accumulate, but still written in SIMD to avoid
3760  * extraction.
3761  *
3762  * Both XXH3_64bits and XXH3_128bits use this subroutine.
3763  */
3764 
3765 XXH_FORCE_INLINE XXH_TARGET_AVX512 void
XXH3_scrambleAcc_avx512(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)3766 XXH3_scrambleAcc_avx512(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3767 {
3768     XXH_ASSERT((((size_t)acc) & 63) == 0);
3769     XXH_STATIC_ASSERT(XXH_STRIPE_LEN == sizeof(__m512i));
3770     {   __m512i* const xacc = (__m512i*) acc;
3771         const __m512i prime32 = _mm512_set1_epi32((int)XXH_PRIME32_1);
3772 
3773         /* xacc[0] ^= (xacc[0] >> 47) */
3774         __m512i const acc_vec     = *xacc;
3775         __m512i const shifted     = _mm512_srli_epi64    (acc_vec, 47);
3776         __m512i const data_vec    = _mm512_xor_si512     (acc_vec, shifted);
3777         /* xacc[0] ^= secret; */
3778         __m512i const key_vec     = _mm512_loadu_si512   (secret);
3779         __m512i const data_key    = _mm512_xor_si512     (data_vec, key_vec);
3780 
3781         /* xacc[0] *= XXH_PRIME32_1; */
3782         __m512i const data_key_hi = _mm512_shuffle_epi32 (data_key, (_MM_PERM_ENUM)_MM_SHUFFLE(0, 3, 0, 1));
3783         __m512i const prod_lo     = _mm512_mul_epu32     (data_key, prime32);
3784         __m512i const prod_hi     = _mm512_mul_epu32     (data_key_hi, prime32);
3785         *xacc = _mm512_add_epi64(prod_lo, _mm512_slli_epi64(prod_hi, 32));
3786     }
3787 }
3788 
3789 XXH_FORCE_INLINE XXH_TARGET_AVX512 void
XXH3_initCustomSecret_avx512(void * XXH_RESTRICT customSecret,xxh_u64 seed64)3790 XXH3_initCustomSecret_avx512(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
3791 {
3792     XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 63) == 0);
3793     XXH_STATIC_ASSERT(XXH_SEC_ALIGN == 64);
3794     XXH_ASSERT(((size_t)customSecret & 63) == 0);
3795     (void)(&XXH_writeLE64);
3796     {   int const nbRounds = XXH_SECRET_DEFAULT_SIZE / sizeof(__m512i);
3797         __m512i const seed = _mm512_mask_set1_epi64(_mm512_set1_epi64((xxh_i64)seed64), 0xAA, (xxh_i64)(0U - seed64));
3798 
3799         const __m512i* const src  = (const __m512i*) ((const void*) XXH3_kSecret);
3800               __m512i* const dest = (      __m512i*) customSecret;
3801         int i;
3802         XXH_ASSERT(((size_t)src & 63) == 0); /* control alignment */
3803         XXH_ASSERT(((size_t)dest & 63) == 0);
3804         for (i=0; i < nbRounds; ++i) {
3805             /* GCC has a bug, _mm512_stream_load_si512 accepts 'void*', not 'void const*',
3806              * this will warn "discards 'const' qualifier". */
3807             union {
3808                 const __m512i* cp;
3809                 void* p;
3810             } remote_const_void;
3811             remote_const_void.cp = src + i;
3812             dest[i] = _mm512_add_epi64(_mm512_stream_load_si512(remote_const_void.p), seed);
3813     }   }
3814 }
3815 
3816 #endif
3817 
3818 #if (XXH_VECTOR == XXH_AVX2) \
3819     || (defined(XXH_DISPATCH_AVX2) && XXH_DISPATCH_AVX2 != 0)
3820 
3821 #ifndef XXH_TARGET_AVX2
3822 # define XXH_TARGET_AVX2  /* disable attribute target */
3823 #endif
3824 
3825 XXH_FORCE_INLINE XXH_TARGET_AVX2 void
XXH3_accumulate_512_avx2(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)3826 XXH3_accumulate_512_avx2( void* XXH_RESTRICT acc,
3827                     const void* XXH_RESTRICT input,
3828                     const void* XXH_RESTRICT secret)
3829 {
3830     XXH_ASSERT((((size_t)acc) & 31) == 0);
3831     {   __m256i* const xacc    =       (__m256i *) acc;
3832         /* Unaligned. This is mainly for pointer arithmetic, and because
3833          * _mm256_loadu_si256 requires  a const __m256i * pointer for some reason. */
3834         const         __m256i* const xinput  = (const __m256i *) input;
3835         /* Unaligned. This is mainly for pointer arithmetic, and because
3836          * _mm256_loadu_si256 requires a const __m256i * pointer for some reason. */
3837         const         __m256i* const xsecret = (const __m256i *) secret;
3838 
3839         size_t i;
3840         for (i=0; i < XXH_STRIPE_LEN/sizeof(__m256i); i++) {
3841             /* data_vec    = xinput[i]; */
3842             __m256i const data_vec    = _mm256_loadu_si256    (xinput+i);
3843             /* key_vec     = xsecret[i]; */
3844             __m256i const key_vec     = _mm256_loadu_si256   (xsecret+i);
3845             /* data_key    = data_vec ^ key_vec; */
3846             __m256i const data_key    = _mm256_xor_si256     (data_vec, key_vec);
3847             /* data_key_lo = data_key >> 32; */
3848             __m256i const data_key_lo = _mm256_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3849             /* product     = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3850             __m256i const product     = _mm256_mul_epu32     (data_key, data_key_lo);
3851             /* xacc[i] += swap(data_vec); */
3852             __m256i const data_swap = _mm256_shuffle_epi32(data_vec, _MM_SHUFFLE(1, 0, 3, 2));
3853             __m256i const sum       = _mm256_add_epi64(xacc[i], data_swap);
3854             /* xacc[i] += product; */
3855             xacc[i] = _mm256_add_epi64(product, sum);
3856     }   }
3857 }
3858 
3859 XXH_FORCE_INLINE XXH_TARGET_AVX2 void
XXH3_scrambleAcc_avx2(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)3860 XXH3_scrambleAcc_avx2(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3861 {
3862     XXH_ASSERT((((size_t)acc) & 31) == 0);
3863     {   __m256i* const xacc = (__m256i*) acc;
3864         /* Unaligned. This is mainly for pointer arithmetic, and because
3865          * _mm256_loadu_si256 requires a const __m256i * pointer for some reason. */
3866         const         __m256i* const xsecret = (const __m256i *) secret;
3867         const __m256i prime32 = _mm256_set1_epi32((int)XXH_PRIME32_1);
3868 
3869         size_t i;
3870         for (i=0; i < XXH_STRIPE_LEN/sizeof(__m256i); i++) {
3871             /* xacc[i] ^= (xacc[i] >> 47) */
3872             __m256i const acc_vec     = xacc[i];
3873             __m256i const shifted     = _mm256_srli_epi64    (acc_vec, 47);
3874             __m256i const data_vec    = _mm256_xor_si256     (acc_vec, shifted);
3875             /* xacc[i] ^= xsecret; */
3876             __m256i const key_vec     = _mm256_loadu_si256   (xsecret+i);
3877             __m256i const data_key    = _mm256_xor_si256     (data_vec, key_vec);
3878 
3879             /* xacc[i] *= XXH_PRIME32_1; */
3880             __m256i const data_key_hi = _mm256_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3881             __m256i const prod_lo     = _mm256_mul_epu32     (data_key, prime32);
3882             __m256i const prod_hi     = _mm256_mul_epu32     (data_key_hi, prime32);
3883             xacc[i] = _mm256_add_epi64(prod_lo, _mm256_slli_epi64(prod_hi, 32));
3884         }
3885     }
3886 }
3887 
XXH3_initCustomSecret_avx2(void * XXH_RESTRICT customSecret,xxh_u64 seed64)3888 XXH_FORCE_INLINE XXH_TARGET_AVX2 void XXH3_initCustomSecret_avx2(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
3889 {
3890     XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 31) == 0);
3891     XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE / sizeof(__m256i)) == 6);
3892     XXH_STATIC_ASSERT(XXH_SEC_ALIGN <= 64);
3893     (void)(&XXH_writeLE64);
3894     XXH_PREFETCH(customSecret);
3895     {   __m256i const seed = _mm256_set_epi64x((xxh_i64)(0U - seed64), (xxh_i64)seed64, (xxh_i64)(0U - seed64), (xxh_i64)seed64);
3896 
3897         const __m256i* const src  = (const __m256i*) ((const void*) XXH3_kSecret);
3898               __m256i*       dest = (      __m256i*) customSecret;
3899 
3900 #       if defined(__GNUC__) || defined(__clang__)
3901         /*
3902          * On GCC & Clang, marking 'dest' as modified will cause the compiler:
3903          *   - do not extract the secret from sse registers in the internal loop
3904          *   - use less common registers, and avoid pushing these reg into stack
3905          */
3906         XXH_COMPILER_GUARD(dest);
3907 #       endif
3908         XXH_ASSERT(((size_t)src & 31) == 0); /* control alignment */
3909         XXH_ASSERT(((size_t)dest & 31) == 0);
3910 
3911         /* GCC -O2 need unroll loop manually */
3912         dest[0] = _mm256_add_epi64(_mm256_stream_load_si256(src+0), seed);
3913         dest[1] = _mm256_add_epi64(_mm256_stream_load_si256(src+1), seed);
3914         dest[2] = _mm256_add_epi64(_mm256_stream_load_si256(src+2), seed);
3915         dest[3] = _mm256_add_epi64(_mm256_stream_load_si256(src+3), seed);
3916         dest[4] = _mm256_add_epi64(_mm256_stream_load_si256(src+4), seed);
3917         dest[5] = _mm256_add_epi64(_mm256_stream_load_si256(src+5), seed);
3918     }
3919 }
3920 
3921 #endif
3922 
3923 /* x86dispatch always generates SSE2 */
3924 #if (XXH_VECTOR == XXH_SSE2) || defined(XXH_X86DISPATCH)
3925 
3926 #ifndef XXH_TARGET_SSE2
3927 # define XXH_TARGET_SSE2  /* disable attribute target */
3928 #endif
3929 
3930 XXH_FORCE_INLINE XXH_TARGET_SSE2 void
XXH3_accumulate_512_sse2(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)3931 XXH3_accumulate_512_sse2( void* XXH_RESTRICT acc,
3932                     const void* XXH_RESTRICT input,
3933                     const void* XXH_RESTRICT secret)
3934 {
3935     /* SSE2 is just a half-scale version of the AVX2 version. */
3936     XXH_ASSERT((((size_t)acc) & 15) == 0);
3937     {   __m128i* const xacc    =       (__m128i *) acc;
3938         /* Unaligned. This is mainly for pointer arithmetic, and because
3939          * _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3940         const         __m128i* const xinput  = (const __m128i *) input;
3941         /* Unaligned. This is mainly for pointer arithmetic, and because
3942          * _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3943         const         __m128i* const xsecret = (const __m128i *) secret;
3944 
3945         size_t i;
3946         for (i=0; i < XXH_STRIPE_LEN/sizeof(__m128i); i++) {
3947             /* data_vec    = xinput[i]; */
3948             __m128i const data_vec    = _mm_loadu_si128   (xinput+i);
3949             /* key_vec     = xsecret[i]; */
3950             __m128i const key_vec     = _mm_loadu_si128   (xsecret+i);
3951             /* data_key    = data_vec ^ key_vec; */
3952             __m128i const data_key    = _mm_xor_si128     (data_vec, key_vec);
3953             /* data_key_lo = data_key >> 32; */
3954             __m128i const data_key_lo = _mm_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3955             /* product     = (data_key & 0xffffffff) * (data_key_lo & 0xffffffff); */
3956             __m128i const product     = _mm_mul_epu32     (data_key, data_key_lo);
3957             /* xacc[i] += swap(data_vec); */
3958             __m128i const data_swap = _mm_shuffle_epi32(data_vec, _MM_SHUFFLE(1,0,3,2));
3959             __m128i const sum       = _mm_add_epi64(xacc[i], data_swap);
3960             /* xacc[i] += product; */
3961             xacc[i] = _mm_add_epi64(product, sum);
3962     }   }
3963 }
3964 
3965 XXH_FORCE_INLINE XXH_TARGET_SSE2 void
XXH3_scrambleAcc_sse2(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)3966 XXH3_scrambleAcc_sse2(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
3967 {
3968     XXH_ASSERT((((size_t)acc) & 15) == 0);
3969     {   __m128i* const xacc = (__m128i*) acc;
3970         /* Unaligned. This is mainly for pointer arithmetic, and because
3971          * _mm_loadu_si128 requires a const __m128i * pointer for some reason. */
3972         const         __m128i* const xsecret = (const __m128i *) secret;
3973         const __m128i prime32 = _mm_set1_epi32((int)XXH_PRIME32_1);
3974 
3975         size_t i;
3976         for (i=0; i < XXH_STRIPE_LEN/sizeof(__m128i); i++) {
3977             /* xacc[i] ^= (xacc[i] >> 47) */
3978             __m128i const acc_vec     = xacc[i];
3979             __m128i const shifted     = _mm_srli_epi64    (acc_vec, 47);
3980             __m128i const data_vec    = _mm_xor_si128     (acc_vec, shifted);
3981             /* xacc[i] ^= xsecret[i]; */
3982             __m128i const key_vec     = _mm_loadu_si128   (xsecret+i);
3983             __m128i const data_key    = _mm_xor_si128     (data_vec, key_vec);
3984 
3985             /* xacc[i] *= XXH_PRIME32_1; */
3986             __m128i const data_key_hi = _mm_shuffle_epi32 (data_key, _MM_SHUFFLE(0, 3, 0, 1));
3987             __m128i const prod_lo     = _mm_mul_epu32     (data_key, prime32);
3988             __m128i const prod_hi     = _mm_mul_epu32     (data_key_hi, prime32);
3989             xacc[i] = _mm_add_epi64(prod_lo, _mm_slli_epi64(prod_hi, 32));
3990         }
3991     }
3992 }
3993 
XXH3_initCustomSecret_sse2(void * XXH_RESTRICT customSecret,xxh_u64 seed64)3994 XXH_FORCE_INLINE XXH_TARGET_SSE2 void XXH3_initCustomSecret_sse2(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
3995 {
3996     XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 15) == 0);
3997     (void)(&XXH_writeLE64);
3998     {   int const nbRounds = XXH_SECRET_DEFAULT_SIZE / sizeof(__m128i);
3999 
4000 #       if defined(_MSC_VER) && defined(_M_IX86) && _MSC_VER < 1900
4001         /* MSVC 32bit mode does not support _mm_set_epi64x before 2015 */
4002         XXH_ALIGN(16) const xxh_i64 seed64x2[2] = { (xxh_i64)seed64, (xxh_i64)(0U - seed64) };
4003         __m128i const seed = _mm_load_si128((__m128i const*)seed64x2);
4004 #       else
4005         __m128i const seed = _mm_set_epi64x((xxh_i64)(0U - seed64), (xxh_i64)seed64);
4006 #       endif
4007         int i;
4008 
4009         const void* const src16 = XXH3_kSecret;
4010         __m128i* dst16 = (__m128i*) customSecret;
4011 #       if defined(__GNUC__) || defined(__clang__)
4012         /*
4013          * On GCC & Clang, marking 'dest' as modified will cause the compiler:
4014          *   - do not extract the secret from sse registers in the internal loop
4015          *   - use less common registers, and avoid pushing these reg into stack
4016          */
4017         XXH_COMPILER_GUARD(dst16);
4018 #       endif
4019         XXH_ASSERT(((size_t)src16 & 15) == 0); /* control alignment */
4020         XXH_ASSERT(((size_t)dst16 & 15) == 0);
4021 
4022         for (i=0; i < nbRounds; ++i) {
4023             dst16[i] = _mm_add_epi64(_mm_load_si128((const __m128i *)src16+i), seed);
4024     }   }
4025 }
4026 
4027 #endif
4028 
4029 #if (XXH_VECTOR == XXH_NEON)
4030 
4031 XXH_FORCE_INLINE void
XXH3_accumulate_512_neon(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)4032 XXH3_accumulate_512_neon( void* XXH_RESTRICT acc,
4033                     const void* XXH_RESTRICT input,
4034                     const void* XXH_RESTRICT secret)
4035 {
4036     XXH_ASSERT((((size_t)acc) & 15) == 0);
4037     {
4038         uint64x2_t* const xacc = (uint64x2_t *) acc;
4039         /* We don't use a uint32x4_t pointer because it causes bus errors on ARMv7. */
4040         uint8_t const* const xinput = (const uint8_t *) input;
4041         uint8_t const* const xsecret  = (const uint8_t *) secret;
4042 
4043         size_t i;
4044         for (i=0; i < XXH_STRIPE_LEN / sizeof(uint64x2_t); i++) {
4045             /* data_vec = xinput[i]; */
4046             uint8x16_t data_vec    = vld1q_u8(xinput  + (i * 16));
4047             /* key_vec  = xsecret[i];  */
4048             uint8x16_t key_vec     = vld1q_u8(xsecret + (i * 16));
4049             uint64x2_t data_key;
4050             uint32x2_t data_key_lo, data_key_hi;
4051             /* xacc[i] += swap(data_vec); */
4052             uint64x2_t const data64  = vreinterpretq_u64_u8(data_vec);
4053             uint64x2_t const swapped = vextq_u64(data64, data64, 1);
4054             xacc[i] = vaddq_u64 (xacc[i], swapped);
4055             /* data_key = data_vec ^ key_vec; */
4056             data_key = vreinterpretq_u64_u8(veorq_u8(data_vec, key_vec));
4057             /* data_key_lo = (uint32x2_t) (data_key & 0xFFFFFFFF);
4058              * data_key_hi = (uint32x2_t) (data_key >> 32);
4059              * data_key = UNDEFINED; */
4060             XXH_SPLIT_IN_PLACE(data_key, data_key_lo, data_key_hi);
4061             /* xacc[i] += (uint64x2_t) data_key_lo * (uint64x2_t) data_key_hi; */
4062             xacc[i] = vmlal_u32 (xacc[i], data_key_lo, data_key_hi);
4063 
4064         }
4065     }
4066 }
4067 
4068 XXH_FORCE_INLINE void
XXH3_scrambleAcc_neon(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)4069 XXH3_scrambleAcc_neon(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4070 {
4071     XXH_ASSERT((((size_t)acc) & 15) == 0);
4072 
4073     {   uint64x2_t* xacc       = (uint64x2_t*) acc;
4074         uint8_t const* xsecret = (uint8_t const*) secret;
4075         uint32x2_t prime       = vdup_n_u32 (XXH_PRIME32_1);
4076 
4077         size_t i;
4078         for (i=0; i < XXH_STRIPE_LEN/sizeof(uint64x2_t); i++) {
4079             /* xacc[i] ^= (xacc[i] >> 47); */
4080             uint64x2_t acc_vec  = xacc[i];
4081             uint64x2_t shifted  = vshrq_n_u64 (acc_vec, 47);
4082             uint64x2_t data_vec = veorq_u64   (acc_vec, shifted);
4083 
4084             /* xacc[i] ^= xsecret[i]; */
4085             uint8x16_t key_vec  = vld1q_u8    (xsecret + (i * 16));
4086             uint64x2_t data_key = veorq_u64   (data_vec, vreinterpretq_u64_u8(key_vec));
4087 
4088             /* xacc[i] *= XXH_PRIME32_1 */
4089             uint32x2_t data_key_lo, data_key_hi;
4090             /* data_key_lo = (uint32x2_t) (xacc[i] & 0xFFFFFFFF);
4091              * data_key_hi = (uint32x2_t) (xacc[i] >> 32);
4092              * xacc[i] = UNDEFINED; */
4093             XXH_SPLIT_IN_PLACE(data_key, data_key_lo, data_key_hi);
4094             {   /*
4095                  * prod_hi = (data_key >> 32) * XXH_PRIME32_1;
4096                  *
4097                  * Avoid vmul_u32 + vshll_n_u32 since Clang 6 and 7 will
4098                  * incorrectly "optimize" this:
4099                  *   tmp     = vmul_u32(vmovn_u64(a), vmovn_u64(b));
4100                  *   shifted = vshll_n_u32(tmp, 32);
4101                  * to this:
4102                  *   tmp     = "vmulq_u64"(a, b); // no such thing!
4103                  *   shifted = vshlq_n_u64(tmp, 32);
4104                  *
4105                  * However, unlike SSE, Clang lacks a 64-bit multiply routine
4106                  * for NEON, and it scalarizes two 64-bit multiplies instead.
4107                  *
4108                  * vmull_u32 has the same timing as vmul_u32, and it avoids
4109                  * this bug completely.
4110                  * See https://bugs.llvm.org/show_bug.cgi?id=39967
4111                  */
4112                 uint64x2_t prod_hi = vmull_u32 (data_key_hi, prime);
4113                 /* xacc[i] = prod_hi << 32; */
4114                 xacc[i] = vshlq_n_u64(prod_hi, 32);
4115                 /* xacc[i] += (prod_hi & 0xFFFFFFFF) * XXH_PRIME32_1; */
4116                 xacc[i] = vmlal_u32(xacc[i], data_key_lo, prime);
4117             }
4118     }   }
4119 }
4120 
4121 #endif
4122 
4123 #if (XXH_VECTOR == XXH_VSX)
4124 
4125 XXH_FORCE_INLINE void
XXH3_accumulate_512_vsx(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)4126 XXH3_accumulate_512_vsx(  void* XXH_RESTRICT acc,
4127                     const void* XXH_RESTRICT input,
4128                     const void* XXH_RESTRICT secret)
4129 {
4130     /* presumed aligned */
4131     unsigned int* const xacc = (unsigned int*) acc;
4132     xxh_u64x2 const* const xinput   = (xxh_u64x2 const*) input;   /* no alignment restriction */
4133     xxh_u64x2 const* const xsecret  = (xxh_u64x2 const*) secret;    /* no alignment restriction */
4134     xxh_u64x2 const v32 = { 32, 32 };
4135     size_t i;
4136     for (i = 0; i < XXH_STRIPE_LEN / sizeof(xxh_u64x2); i++) {
4137         /* data_vec = xinput[i]; */
4138         xxh_u64x2 const data_vec = XXH_vec_loadu(xinput + i);
4139         /* key_vec = xsecret[i]; */
4140         xxh_u64x2 const key_vec  = XXH_vec_loadu(xsecret + i);
4141         xxh_u64x2 const data_key = data_vec ^ key_vec;
4142         /* shuffled = (data_key << 32) | (data_key >> 32); */
4143         xxh_u32x4 const shuffled = (xxh_u32x4)vec_rl(data_key, v32);
4144         /* product = ((xxh_u64x2)data_key & 0xFFFFFFFF) * ((xxh_u64x2)shuffled & 0xFFFFFFFF); */
4145         xxh_u64x2 const product  = XXH_vec_mulo((xxh_u32x4)data_key, shuffled);
4146         /* acc_vec = xacc[i]; */
4147         xxh_u64x2 acc_vec        = (xxh_u64x2)vec_xl(0, xacc + 4 * i);
4148         acc_vec += product;
4149 
4150         /* swap high and low halves */
4151 #ifdef __s390x__
4152         acc_vec += vec_permi(data_vec, data_vec, 2);
4153 #else
4154         acc_vec += vec_xxpermdi(data_vec, data_vec, 2);
4155 #endif
4156         /* xacc[i] = acc_vec; */
4157         vec_xst((xxh_u32x4)acc_vec, 0, xacc + 4 * i);
4158     }
4159 }
4160 
4161 XXH_FORCE_INLINE void
XXH3_scrambleAcc_vsx(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)4162 XXH3_scrambleAcc_vsx(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4163 {
4164     XXH_ASSERT((((size_t)acc) & 15) == 0);
4165 
4166     {         xxh_u64x2* const xacc    =       (xxh_u64x2*) acc;
4167         const xxh_u64x2* const xsecret = (const xxh_u64x2*) secret;
4168         /* constants */
4169         xxh_u64x2 const v32  = { 32, 32 };
4170         xxh_u64x2 const v47 = { 47, 47 };
4171         xxh_u32x4 const prime = { XXH_PRIME32_1, XXH_PRIME32_1, XXH_PRIME32_1, XXH_PRIME32_1 };
4172         size_t i;
4173         for (i = 0; i < XXH_STRIPE_LEN / sizeof(xxh_u64x2); i++) {
4174             /* xacc[i] ^= (xacc[i] >> 47); */
4175             xxh_u64x2 const acc_vec  = xacc[i];
4176             xxh_u64x2 const data_vec = acc_vec ^ (acc_vec >> v47);
4177 
4178             /* xacc[i] ^= xsecret[i]; */
4179             xxh_u64x2 const key_vec  = XXH_vec_loadu(xsecret + i);
4180             xxh_u64x2 const data_key = data_vec ^ key_vec;
4181 
4182             /* xacc[i] *= XXH_PRIME32_1 */
4183             /* prod_lo = ((xxh_u64x2)data_key & 0xFFFFFFFF) * ((xxh_u64x2)prime & 0xFFFFFFFF);  */
4184             xxh_u64x2 const prod_even  = XXH_vec_mule((xxh_u32x4)data_key, prime);
4185             /* prod_hi = ((xxh_u64x2)data_key >> 32) * ((xxh_u64x2)prime >> 32);  */
4186             xxh_u64x2 const prod_odd  = XXH_vec_mulo((xxh_u32x4)data_key, prime);
4187             xacc[i] = prod_odd + (prod_even << v32);
4188     }   }
4189 }
4190 
4191 #endif
4192 
4193 /* scalar variants - universal */
4194 
4195 XXH_FORCE_INLINE void
XXH3_accumulate_512_scalar(void * XXH_RESTRICT acc,const void * XXH_RESTRICT input,const void * XXH_RESTRICT secret)4196 XXH3_accumulate_512_scalar(void* XXH_RESTRICT acc,
4197                      const void* XXH_RESTRICT input,
4198                      const void* XXH_RESTRICT secret)
4199 {
4200     xxh_u64* const xacc = (xxh_u64*) acc; /* presumed aligned */
4201     const xxh_u8* const xinput  = (const xxh_u8*) input;  /* no alignment restriction */
4202     const xxh_u8* const xsecret = (const xxh_u8*) secret;   /* no alignment restriction */
4203     size_t i;
4204     XXH_ASSERT(((size_t)acc & (XXH_ACC_ALIGN-1)) == 0);
4205     for (i=0; i < XXH_ACC_NB; i++) {
4206         xxh_u64 const data_val = XXH_readLE64(xinput + 8*i);
4207         xxh_u64 const data_key = data_val ^ XXH_readLE64(xsecret + i*8);
4208         xacc[i ^ 1] += data_val; /* swap adjacent lanes */
4209         xacc[i] += XXH_mult32to64(data_key & 0xFFFFFFFF, data_key >> 32);
4210     }
4211 }
4212 
4213 XXH_FORCE_INLINE void
XXH3_scrambleAcc_scalar(void * XXH_RESTRICT acc,const void * XXH_RESTRICT secret)4214 XXH3_scrambleAcc_scalar(void* XXH_RESTRICT acc, const void* XXH_RESTRICT secret)
4215 {
4216     xxh_u64* const xacc = (xxh_u64*) acc;   /* presumed aligned */
4217     const xxh_u8* const xsecret = (const xxh_u8*) secret;   /* no alignment restriction */
4218     size_t i;
4219     XXH_ASSERT((((size_t)acc) & (XXH_ACC_ALIGN-1)) == 0);
4220     for (i=0; i < XXH_ACC_NB; i++) {
4221         xxh_u64 const key64 = XXH_readLE64(xsecret + 8*i);
4222         xxh_u64 acc64 = xacc[i];
4223         acc64 = XXH_xorshift64(acc64, 47);
4224         acc64 ^= key64;
4225         acc64 *= XXH_PRIME32_1;
4226         xacc[i] = acc64;
4227     }
4228 }
4229 
4230 XXH_FORCE_INLINE void
XXH3_initCustomSecret_scalar(void * XXH_RESTRICT customSecret,xxh_u64 seed64)4231 XXH3_initCustomSecret_scalar(void* XXH_RESTRICT customSecret, xxh_u64 seed64)
4232 {
4233     /*
4234      * We need a separate pointer for the hack below,
4235      * which requires a non-const pointer.
4236      * Any decent compiler will optimize this out otherwise.
4237      */
4238     const xxh_u8* kSecretPtr = XXH3_kSecret;
4239     XXH_STATIC_ASSERT((XXH_SECRET_DEFAULT_SIZE & 15) == 0);
4240 
4241 #if defined(__clang__) && defined(__aarch64__)
4242     /*
4243      * UGLY HACK:
4244      * Clang generates a bunch of MOV/MOVK pairs for aarch64, and they are
4245      * placed sequentially, in order, at the top of the unrolled loop.
4246      *
4247      * While MOVK is great for generating constants (2 cycles for a 64-bit
4248      * constant compared to 4 cycles for LDR), long MOVK chains stall the
4249      * integer pipelines:
4250      *   I   L   S
4251      * MOVK
4252      * MOVK
4253      * MOVK
4254      * MOVK
4255      * ADD
4256      * SUB      STR
4257      *          STR
4258      * By forcing loads from memory (as the asm line causes Clang to assume
4259      * that XXH3_kSecretPtr has been changed), the pipelines are used more
4260      * efficiently:
4261      *   I   L   S
4262      *      LDR
4263      *  ADD LDR
4264      *  SUB     STR
4265      *          STR
4266      * XXH3_64bits_withSeed, len == 256, Snapdragon 835
4267      *   without hack: 2654.4 MB/s
4268      *   with hack:    3202.9 MB/s
4269      */
4270     XXH_COMPILER_GUARD(kSecretPtr);
4271 #endif
4272     /*
4273      * Note: in debug mode, this overrides the asm optimization
4274      * and Clang will emit MOVK chains again.
4275      */
4276     XXH_ASSERT(kSecretPtr == XXH3_kSecret);
4277 
4278     {   int const nbRounds = XXH_SECRET_DEFAULT_SIZE / 16;
4279         int i;
4280         for (i=0; i < nbRounds; i++) {
4281             /*
4282              * The asm hack causes Clang to assume that kSecretPtr aliases with
4283              * customSecret, and on aarch64, this prevented LDP from merging two
4284              * loads together for free. Putting the loads together before the stores
4285              * properly generates LDP.
4286              */
4287             xxh_u64 lo = XXH_readLE64(kSecretPtr + 16*i)     + seed64;
4288             xxh_u64 hi = XXH_readLE64(kSecretPtr + 16*i + 8) - seed64;
4289             XXH_writeLE64((xxh_u8*)customSecret + 16*i,     lo);
4290             XXH_writeLE64((xxh_u8*)customSecret + 16*i + 8, hi);
4291     }   }
4292 }
4293 
4294 
4295 typedef void (*XXH3_f_accumulate_512)(void* XXH_RESTRICT, const void*, const void*);
4296 typedef void (*XXH3_f_scrambleAcc)(void* XXH_RESTRICT, const void*);
4297 typedef void (*XXH3_f_initCustomSecret)(void* XXH_RESTRICT, xxh_u64);
4298 
4299 
4300 #if (XXH_VECTOR == XXH_AVX512)
4301 
4302 #define XXH3_accumulate_512 XXH3_accumulate_512_avx512
4303 #define XXH3_scrambleAcc    XXH3_scrambleAcc_avx512
4304 #define XXH3_initCustomSecret XXH3_initCustomSecret_avx512
4305 
4306 #elif (XXH_VECTOR == XXH_AVX2)
4307 
4308 #define XXH3_accumulate_512 XXH3_accumulate_512_avx2
4309 #define XXH3_scrambleAcc    XXH3_scrambleAcc_avx2
4310 #define XXH3_initCustomSecret XXH3_initCustomSecret_avx2
4311 
4312 #elif (XXH_VECTOR == XXH_SSE2)
4313 
4314 #define XXH3_accumulate_512 XXH3_accumulate_512_sse2
4315 #define XXH3_scrambleAcc    XXH3_scrambleAcc_sse2
4316 #define XXH3_initCustomSecret XXH3_initCustomSecret_sse2
4317 
4318 #elif (XXH_VECTOR == XXH_NEON)
4319 
4320 #define XXH3_accumulate_512 XXH3_accumulate_512_neon
4321 #define XXH3_scrambleAcc    XXH3_scrambleAcc_neon
4322 #define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4323 
4324 #elif (XXH_VECTOR == XXH_VSX)
4325 
4326 #define XXH3_accumulate_512 XXH3_accumulate_512_vsx
4327 #define XXH3_scrambleAcc    XXH3_scrambleAcc_vsx
4328 #define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4329 
4330 #else /* scalar */
4331 
4332 #define XXH3_accumulate_512 XXH3_accumulate_512_scalar
4333 #define XXH3_scrambleAcc    XXH3_scrambleAcc_scalar
4334 #define XXH3_initCustomSecret XXH3_initCustomSecret_scalar
4335 
4336 #endif
4337 
4338 
4339 
4340 #ifndef XXH_PREFETCH_DIST
4341 #  ifdef __clang__
4342 #    define XXH_PREFETCH_DIST 320
4343 #  else
4344 #    if (XXH_VECTOR == XXH_AVX512)
4345 #      define XXH_PREFETCH_DIST 512
4346 #    else
4347 #      define XXH_PREFETCH_DIST 384
4348 #    endif
4349 #  endif  /* __clang__ */
4350 #endif  /* XXH_PREFETCH_DIST */
4351 
4352 /*
4353  * XXH3_accumulate()
4354  * Loops over XXH3_accumulate_512().
4355  * Assumption: nbStripes will not overflow the secret size
4356  */
4357 XXH_FORCE_INLINE void
XXH3_accumulate(xxh_u64 * XXH_RESTRICT acc,const xxh_u8 * XXH_RESTRICT input,const xxh_u8 * XXH_RESTRICT secret,size_t nbStripes,XXH3_f_accumulate_512 f_acc512)4358 XXH3_accumulate(     xxh_u64* XXH_RESTRICT acc,
4359                 const xxh_u8* XXH_RESTRICT input,
4360                 const xxh_u8* XXH_RESTRICT secret,
4361                       size_t nbStripes,
4362                       XXH3_f_accumulate_512 f_acc512)
4363 {
4364     size_t n;
4365     for (n = 0; n < nbStripes; n++ ) {
4366         const xxh_u8* const in = input + n*XXH_STRIPE_LEN;
4367         XXH_PREFETCH(in + XXH_PREFETCH_DIST);
4368         f_acc512(acc,
4369                  in,
4370                  secret + n*XXH_SECRET_CONSUME_RATE);
4371     }
4372 }
4373 
4374 XXH_FORCE_INLINE void
XXH3_hashLong_internal_loop(xxh_u64 * XXH_RESTRICT acc,const xxh_u8 * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble)4375 XXH3_hashLong_internal_loop(xxh_u64* XXH_RESTRICT acc,
4376                       const xxh_u8* XXH_RESTRICT input, size_t len,
4377                       const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
4378                             XXH3_f_accumulate_512 f_acc512,
4379                             XXH3_f_scrambleAcc f_scramble)
4380 {
4381     size_t const nbStripesPerBlock = (secretSize - XXH_STRIPE_LEN) / XXH_SECRET_CONSUME_RATE;
4382     size_t const block_len = XXH_STRIPE_LEN * nbStripesPerBlock;
4383     size_t const nb_blocks = (len - 1) / block_len;
4384 
4385     size_t n;
4386 
4387     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
4388 
4389     for (n = 0; n < nb_blocks; n++) {
4390         XXH3_accumulate(acc, input + n*block_len, secret, nbStripesPerBlock, f_acc512);
4391         f_scramble(acc, secret + secretSize - XXH_STRIPE_LEN);
4392     }
4393 
4394     /* last partial block */
4395     XXH_ASSERT(len > XXH_STRIPE_LEN);
4396     {   size_t const nbStripes = ((len - 1) - (block_len * nb_blocks)) / XXH_STRIPE_LEN;
4397         XXH_ASSERT(nbStripes <= (secretSize / XXH_SECRET_CONSUME_RATE));
4398         XXH3_accumulate(acc, input + nb_blocks*block_len, secret, nbStripes, f_acc512);
4399 
4400         /* last stripe */
4401         {   const xxh_u8* const p = input + len - XXH_STRIPE_LEN;
4402 #define XXH_SECRET_LASTACC_START 7  /* not aligned on 8, last secret is different from acc & scrambler */
4403             f_acc512(acc, p, secret + secretSize - XXH_STRIPE_LEN - XXH_SECRET_LASTACC_START);
4404     }   }
4405 }
4406 
4407 XXH_FORCE_INLINE xxh_u64
XXH3_mix2Accs(const xxh_u64 * XXH_RESTRICT acc,const xxh_u8 * XXH_RESTRICT secret)4408 XXH3_mix2Accs(const xxh_u64* XXH_RESTRICT acc, const xxh_u8* XXH_RESTRICT secret)
4409 {
4410     return XXH3_mul128_fold64(
4411                acc[0] ^ XXH_readLE64(secret),
4412                acc[1] ^ XXH_readLE64(secret+8) );
4413 }
4414 
4415 static XXH64_hash_t
XXH3_mergeAccs(const xxh_u64 * XXH_RESTRICT acc,const xxh_u8 * XXH_RESTRICT secret,xxh_u64 start)4416 XXH3_mergeAccs(const xxh_u64* XXH_RESTRICT acc, const xxh_u8* XXH_RESTRICT secret, xxh_u64 start)
4417 {
4418     xxh_u64 result64 = start;
4419     size_t i = 0;
4420 
4421     for (i = 0; i < 4; i++) {
4422         result64 += XXH3_mix2Accs(acc+2*i, secret + 16*i);
4423 #if defined(__clang__)                                /* Clang */ \
4424     && (defined(__arm__) || defined(__thumb__))       /* ARMv7 */ \
4425     && (defined(__ARM_NEON) || defined(__ARM_NEON__)) /* NEON */  \
4426     && !defined(XXH_ENABLE_AUTOVECTORIZE)             /* Define to disable */
4427         /*
4428          * UGLY HACK:
4429          * Prevent autovectorization on Clang ARMv7-a. Exact same problem as
4430          * the one in XXH3_len_129to240_64b. Speeds up shorter keys > 240b.
4431          * XXH3_64bits, len == 256, Snapdragon 835:
4432          *   without hack: 2063.7 MB/s
4433          *   with hack:    2560.7 MB/s
4434          */
4435         XXH_COMPILER_GUARD(result64);
4436 #endif
4437     }
4438 
4439     return XXH3_avalanche(result64);
4440 }
4441 
4442 #define XXH3_INIT_ACC { XXH_PRIME32_3, XXH_PRIME64_1, XXH_PRIME64_2, XXH_PRIME64_3, \
4443                         XXH_PRIME64_4, XXH_PRIME32_2, XXH_PRIME64_5, XXH_PRIME32_1 }
4444 
4445 XXH_FORCE_INLINE XXH64_hash_t
XXH3_hashLong_64b_internal(const void * XXH_RESTRICT input,size_t len,const void * XXH_RESTRICT secret,size_t secretSize,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble)4446 XXH3_hashLong_64b_internal(const void* XXH_RESTRICT input, size_t len,
4447                            const void* XXH_RESTRICT secret, size_t secretSize,
4448                            XXH3_f_accumulate_512 f_acc512,
4449                            XXH3_f_scrambleAcc f_scramble)
4450 {
4451     XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[XXH_ACC_NB] = XXH3_INIT_ACC;
4452 
4453     XXH3_hashLong_internal_loop(acc, (const xxh_u8*)input, len, (const xxh_u8*)secret, secretSize, f_acc512, f_scramble);
4454 
4455     /* converge into final hash */
4456     XXH_STATIC_ASSERT(sizeof(acc) == 64);
4457     /* do not align on 8, so that the secret is different from the accumulator */
4458 #define XXH_SECRET_MERGEACCS_START 11
4459     XXH_ASSERT(secretSize >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
4460     return XXH3_mergeAccs(acc, (const xxh_u8*)secret + XXH_SECRET_MERGEACCS_START, (xxh_u64)len * XXH_PRIME64_1);
4461 }
4462 
4463 /*
4464  * It's important for performance to transmit secret's size (when it's static)
4465  * so that the compiler can properly optimize the vectorized loop.
4466  * This makes a big performance difference for "medium" keys (<1 KB) when using AVX instruction set.
4467  */
4468 XXH_FORCE_INLINE XXH64_hash_t
XXH3_hashLong_64b_withSecret(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,const xxh_u8 * XXH_RESTRICT secret,size_t secretLen)4469 XXH3_hashLong_64b_withSecret(const void* XXH_RESTRICT input, size_t len,
4470                              XXH64_hash_t seed64, const xxh_u8* XXH_RESTRICT secret, size_t secretLen)
4471 {
4472     (void)seed64;
4473     return XXH3_hashLong_64b_internal(input, len, secret, secretLen, XXH3_accumulate_512, XXH3_scrambleAcc);
4474 }
4475 
4476 /*
4477  * It's preferable for performance that XXH3_hashLong is not inlined,
4478  * as it results in a smaller function for small data, easier to the instruction cache.
4479  * Note that inside this no_inline function, we do inline the internal loop,
4480  * and provide a statically defined secret size to allow optimization of vector loop.
4481  */
4482 XXH_NO_INLINE XXH64_hash_t
XXH3_hashLong_64b_default(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,const xxh_u8 * XXH_RESTRICT secret,size_t secretLen)4483 XXH3_hashLong_64b_default(const void* XXH_RESTRICT input, size_t len,
4484                           XXH64_hash_t seed64, const xxh_u8* XXH_RESTRICT secret, size_t secretLen)
4485 {
4486     (void)seed64; (void)secret; (void)secretLen;
4487     return XXH3_hashLong_64b_internal(input, len, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_accumulate_512, XXH3_scrambleAcc);
4488 }
4489 
4490 /*
4491  * XXH3_hashLong_64b_withSeed():
4492  * Generate a custom key based on alteration of default XXH3_kSecret with the seed,
4493  * and then use this key for long mode hashing.
4494  *
4495  * This operation is decently fast but nonetheless costs a little bit of time.
4496  * Try to avoid it whenever possible (typically when seed==0).
4497  *
4498  * It's important for performance that XXH3_hashLong is not inlined. Not sure
4499  * why (uop cache maybe?), but the difference is large and easily measurable.
4500  */
4501 XXH_FORCE_INLINE XXH64_hash_t
XXH3_hashLong_64b_withSeed_internal(const void * input,size_t len,XXH64_hash_t seed,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble,XXH3_f_initCustomSecret f_initSec)4502 XXH3_hashLong_64b_withSeed_internal(const void* input, size_t len,
4503                                     XXH64_hash_t seed,
4504                                     XXH3_f_accumulate_512 f_acc512,
4505                                     XXH3_f_scrambleAcc f_scramble,
4506                                     XXH3_f_initCustomSecret f_initSec)
4507 {
4508     if (seed == 0)
4509         return XXH3_hashLong_64b_internal(input, len,
4510                                           XXH3_kSecret, sizeof(XXH3_kSecret),
4511                                           f_acc512, f_scramble);
4512     {   XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
4513         f_initSec(secret, seed);
4514         return XXH3_hashLong_64b_internal(input, len, secret, sizeof(secret),
4515                                           f_acc512, f_scramble);
4516     }
4517 }
4518 
4519 /*
4520  * It's important for performance that XXH3_hashLong is not inlined.
4521  */
4522 XXH_NO_INLINE XXH64_hash_t
XXH3_hashLong_64b_withSeed(const void * input,size_t len,XXH64_hash_t seed,const xxh_u8 * secret,size_t secretLen)4523 XXH3_hashLong_64b_withSeed(const void* input, size_t len,
4524                            XXH64_hash_t seed, const xxh_u8* secret, size_t secretLen)
4525 {
4526     (void)secret; (void)secretLen;
4527     return XXH3_hashLong_64b_withSeed_internal(input, len, seed,
4528                 XXH3_accumulate_512, XXH3_scrambleAcc, XXH3_initCustomSecret);
4529 }
4530 
4531 
4532 typedef XXH64_hash_t (*XXH3_hashLong64_f)(const void* XXH_RESTRICT, size_t,
4533                                           XXH64_hash_t, const xxh_u8* XXH_RESTRICT, size_t);
4534 
4535 XXH_FORCE_INLINE XXH64_hash_t
XXH3_64bits_internal(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,const void * XXH_RESTRICT secret,size_t secretLen,XXH3_hashLong64_f f_hashLong)4536 XXH3_64bits_internal(const void* XXH_RESTRICT input, size_t len,
4537                      XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen,
4538                      XXH3_hashLong64_f f_hashLong)
4539 {
4540     XXH_ASSERT(secretLen >= XXH3_SECRET_SIZE_MIN);
4541     /*
4542      * If an action is to be taken if `secretLen` condition is not respected,
4543      * it should be done here.
4544      * For now, it's a contract pre-condition.
4545      * Adding a check and a branch here would cost performance at every hash.
4546      * Also, note that function signature doesn't offer room to return an error.
4547      */
4548     if (len <= 16)
4549         return XXH3_len_0to16_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, seed64);
4550     if (len <= 128)
4551         return XXH3_len_17to128_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
4552     if (len <= XXH3_MIDSIZE_MAX)
4553         return XXH3_len_129to240_64b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
4554     return f_hashLong(input, len, seed64, (const xxh_u8*)secret, secretLen);
4555 }
4556 
4557 
4558 /* ===   Public entry point   === */
4559 
4560 /*! @ingroup xxh3_family */
XXH3_64bits(const void * input,size_t len)4561 XXH_PUBLIC_API XXH64_hash_t XXH3_64bits(const void* input, size_t len)
4562 {
4563     return XXH3_64bits_internal(input, len, 0, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_hashLong_64b_default);
4564 }
4565 
4566 /*! @ingroup xxh3_family */
4567 XXH_PUBLIC_API XXH64_hash_t
XXH3_64bits_withSecret(const void * input,size_t len,const void * secret,size_t secretSize)4568 XXH3_64bits_withSecret(const void* input, size_t len, const void* secret, size_t secretSize)
4569 {
4570     return XXH3_64bits_internal(input, len, 0, secret, secretSize, XXH3_hashLong_64b_withSecret);
4571 }
4572 
4573 /*! @ingroup xxh3_family */
4574 XXH_PUBLIC_API XXH64_hash_t
XXH3_64bits_withSeed(const void * input,size_t len,XXH64_hash_t seed)4575 XXH3_64bits_withSeed(const void* input, size_t len, XXH64_hash_t seed)
4576 {
4577     return XXH3_64bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), XXH3_hashLong_64b_withSeed);
4578 }
4579 
4580 XXH_PUBLIC_API XXH64_hash_t
XXH3_64bits_withSecretandSeed(const void * input,size_t len,const void * secret,size_t secretSize,XXH64_hash_t seed)4581 XXH3_64bits_withSecretandSeed(const void* input, size_t len, const void* secret, size_t secretSize, XXH64_hash_t seed)
4582 {
4583     if (len <= XXH3_MIDSIZE_MAX)
4584         return XXH3_64bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), NULL);
4585     return XXH3_hashLong_64b_withSecret(input, len, seed, (const xxh_u8*)secret, secretSize);
4586 }
4587 
4588 
4589 /* ===   XXH3 streaming   === */
4590 
4591 /*
4592  * Malloc's a pointer that is always aligned to align.
4593  *
4594  * This must be freed with `XXH_alignedFree()`.
4595  *
4596  * malloc typically guarantees 16 byte alignment on 64-bit systems and 8 byte
4597  * alignment on 32-bit. This isn't enough for the 32 byte aligned loads in AVX2
4598  * or on 32-bit, the 16 byte aligned loads in SSE2 and NEON.
4599  *
4600  * This underalignment previously caused a rather obvious crash which went
4601  * completely unnoticed due to XXH3_createState() not actually being tested.
4602  * Credit to RedSpah for noticing this bug.
4603  *
4604  * The alignment is done manually: Functions like posix_memalign or _mm_malloc
4605  * are avoided: To maintain portability, we would have to write a fallback
4606  * like this anyways, and besides, testing for the existence of library
4607  * functions without relying on external build tools is impossible.
4608  *
4609  * The method is simple: Overallocate, manually align, and store the offset
4610  * to the original behind the returned pointer.
4611  *
4612  * Align must be a power of 2 and 8 <= align <= 128.
4613  */
XXH_alignedMalloc(size_t s,size_t align)4614 static void* XXH_alignedMalloc(size_t s, size_t align)
4615 {
4616     XXH_ASSERT(align <= 128 && align >= 8); /* range check */
4617     XXH_ASSERT((align & (align-1)) == 0);   /* power of 2 */
4618     XXH_ASSERT(s != 0 && s < (s + align));  /* empty/overflow */
4619     {   /* Overallocate to make room for manual realignment and an offset byte */
4620         xxh_u8* base = (xxh_u8*)XXH_malloc(s + align);
4621         if (base != NULL) {
4622             /*
4623              * Get the offset needed to align this pointer.
4624              *
4625              * Even if the returned pointer is aligned, there will always be
4626              * at least one byte to store the offset to the original pointer.
4627              */
4628             size_t offset = align - ((size_t)base & (align - 1)); /* base % align */
4629             /* Add the offset for the now-aligned pointer */
4630             xxh_u8* ptr = base + offset;
4631 
4632             XXH_ASSERT((size_t)ptr % align == 0);
4633 
4634             /* Store the offset immediately before the returned pointer. */
4635             ptr[-1] = (xxh_u8)offset;
4636             return ptr;
4637         }
4638         return NULL;
4639     }
4640 }
4641 /*
4642  * Frees an aligned pointer allocated by XXH_alignedMalloc(). Don't pass
4643  * normal malloc'd pointers, XXH_alignedMalloc has a specific data layout.
4644  */
XXH_alignedFree(void * p)4645 static void XXH_alignedFree(void* p)
4646 {
4647     if (p != NULL) {
4648         xxh_u8* ptr = (xxh_u8*)p;
4649         /* Get the offset byte we added in XXH_malloc. */
4650         xxh_u8 offset = ptr[-1];
4651         /* Free the original malloc'd pointer */
4652         xxh_u8* base = ptr - offset;
4653         XXH_free(base);
4654     }
4655 }
4656 /*! @ingroup xxh3_family */
XXH3_createState(void)4657 XXH_PUBLIC_API XXH3_state_t* XXH3_createState(void)
4658 {
4659     XXH3_state_t* const state = (XXH3_state_t*)XXH_alignedMalloc(sizeof(XXH3_state_t), 64);
4660     if (state==NULL) return NULL;
4661     XXH3_INITSTATE(state);
4662     return state;
4663 }
4664 
4665 /*! @ingroup xxh3_family */
XXH3_freeState(XXH3_state_t * statePtr)4666 XXH_PUBLIC_API XXH_errorcode XXH3_freeState(XXH3_state_t* statePtr)
4667 {
4668     XXH_alignedFree(statePtr);
4669     return XXH_OK;
4670 }
4671 
4672 /*! @ingroup xxh3_family */
4673 XXH_PUBLIC_API void
XXH3_copyState(XXH3_state_t * dst_state,const XXH3_state_t * src_state)4674 XXH3_copyState(XXH3_state_t* dst_state, const XXH3_state_t* src_state)
4675 {
4676     XXH_memcpy(dst_state, src_state, sizeof(*dst_state));
4677 }
4678 
4679 static void
XXH3_reset_internal(XXH3_state_t * statePtr,XXH64_hash_t seed,const void * secret,size_t secretSize)4680 XXH3_reset_internal(XXH3_state_t* statePtr,
4681                     XXH64_hash_t seed,
4682                     const void* secret, size_t secretSize)
4683 {
4684     size_t const initStart = offsetof(XXH3_state_t, bufferedSize);
4685     size_t const initLength = offsetof(XXH3_state_t, nbStripesPerBlock) - initStart;
4686     XXH_ASSERT(offsetof(XXH3_state_t, nbStripesPerBlock) > initStart);
4687     XXH_ASSERT(statePtr != NULL);
4688     /* set members from bufferedSize to nbStripesPerBlock (excluded) to 0 */
4689     memset((char*)statePtr + initStart, 0, initLength);
4690     statePtr->acc[0] = XXH_PRIME32_3;
4691     statePtr->acc[1] = XXH_PRIME64_1;
4692     statePtr->acc[2] = XXH_PRIME64_2;
4693     statePtr->acc[3] = XXH_PRIME64_3;
4694     statePtr->acc[4] = XXH_PRIME64_4;
4695     statePtr->acc[5] = XXH_PRIME32_2;
4696     statePtr->acc[6] = XXH_PRIME64_5;
4697     statePtr->acc[7] = XXH_PRIME32_1;
4698     statePtr->seed = seed;
4699     statePtr->useSeed = (seed != 0);
4700     statePtr->extSecret = (const unsigned char*)secret;
4701     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
4702     statePtr->secretLimit = secretSize - XXH_STRIPE_LEN;
4703     statePtr->nbStripesPerBlock = statePtr->secretLimit / XXH_SECRET_CONSUME_RATE;
4704 }
4705 
4706 /*! @ingroup xxh3_family */
4707 XXH_PUBLIC_API XXH_errorcode
XXH3_64bits_reset(XXH3_state_t * statePtr)4708 XXH3_64bits_reset(XXH3_state_t* statePtr)
4709 {
4710     if (statePtr == NULL) return XXH_ERROR;
4711     XXH3_reset_internal(statePtr, 0, XXH3_kSecret, XXH_SECRET_DEFAULT_SIZE);
4712     return XXH_OK;
4713 }
4714 
4715 /*! @ingroup xxh3_family */
4716 XXH_PUBLIC_API XXH_errorcode
XXH3_64bits_reset_withSecret(XXH3_state_t * statePtr,const void * secret,size_t secretSize)4717 XXH3_64bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize)
4718 {
4719     if (statePtr == NULL) return XXH_ERROR;
4720     XXH3_reset_internal(statePtr, 0, secret, secretSize);
4721     if (secret == NULL) return XXH_ERROR;
4722     if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
4723     return XXH_OK;
4724 }
4725 
4726 /*! @ingroup xxh3_family */
4727 XXH_PUBLIC_API XXH_errorcode
XXH3_64bits_reset_withSeed(XXH3_state_t * statePtr,XXH64_hash_t seed)4728 XXH3_64bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed)
4729 {
4730     if (statePtr == NULL) return XXH_ERROR;
4731     if (seed==0) return XXH3_64bits_reset(statePtr);
4732     if ((seed != statePtr->seed) || (statePtr->extSecret != NULL))
4733         XXH3_initCustomSecret(statePtr->customSecret, seed);
4734     XXH3_reset_internal(statePtr, seed, NULL, XXH_SECRET_DEFAULT_SIZE);
4735     return XXH_OK;
4736 }
4737 
4738 /*! @ingroup xxh3_family */
4739 XXH_PUBLIC_API XXH_errorcode
XXH3_64bits_reset_withSecretandSeed(XXH3_state_t * statePtr,const void * secret,size_t secretSize,XXH64_hash_t seed64)4740 XXH3_64bits_reset_withSecretandSeed(XXH3_state_t* statePtr, const void* secret, size_t secretSize, XXH64_hash_t seed64)
4741 {
4742     if (statePtr == NULL) return XXH_ERROR;
4743     if (secret == NULL) return XXH_ERROR;
4744     if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
4745     XXH3_reset_internal(statePtr, seed64, secret, secretSize);
4746     statePtr->useSeed = 1; /* always, even if seed64==0 */
4747     return XXH_OK;
4748 }
4749 
4750 /* Note : when XXH3_consumeStripes() is invoked,
4751  * there must be a guarantee that at least one more byte must be consumed from input
4752  * so that the function can blindly consume all stripes using the "normal" secret segment */
4753 XXH_FORCE_INLINE void
XXH3_consumeStripes(xxh_u64 * XXH_RESTRICT acc,size_t * XXH_RESTRICT nbStripesSoFarPtr,size_t nbStripesPerBlock,const xxh_u8 * XXH_RESTRICT input,size_t nbStripes,const xxh_u8 * XXH_RESTRICT secret,size_t secretLimit,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble)4754 XXH3_consumeStripes(xxh_u64* XXH_RESTRICT acc,
4755                     size_t* XXH_RESTRICT nbStripesSoFarPtr, size_t nbStripesPerBlock,
4756                     const xxh_u8* XXH_RESTRICT input, size_t nbStripes,
4757                     const xxh_u8* XXH_RESTRICT secret, size_t secretLimit,
4758                     XXH3_f_accumulate_512 f_acc512,
4759                     XXH3_f_scrambleAcc f_scramble)
4760 {
4761     XXH_ASSERT(nbStripes <= nbStripesPerBlock);  /* can handle max 1 scramble per invocation */
4762     XXH_ASSERT(*nbStripesSoFarPtr < nbStripesPerBlock);
4763     if (nbStripesPerBlock - *nbStripesSoFarPtr <= nbStripes) {
4764         /* need a scrambling operation */
4765         size_t const nbStripesToEndofBlock = nbStripesPerBlock - *nbStripesSoFarPtr;
4766         size_t const nbStripesAfterBlock = nbStripes - nbStripesToEndofBlock;
4767         XXH3_accumulate(acc, input, secret + nbStripesSoFarPtr[0] * XXH_SECRET_CONSUME_RATE, nbStripesToEndofBlock, f_acc512);
4768         f_scramble(acc, secret + secretLimit);
4769         XXH3_accumulate(acc, input + nbStripesToEndofBlock * XXH_STRIPE_LEN, secret, nbStripesAfterBlock, f_acc512);
4770         *nbStripesSoFarPtr = nbStripesAfterBlock;
4771     } else {
4772         XXH3_accumulate(acc, input, secret + nbStripesSoFarPtr[0] * XXH_SECRET_CONSUME_RATE, nbStripes, f_acc512);
4773         *nbStripesSoFarPtr += nbStripes;
4774     }
4775 }
4776 
4777 #ifndef XXH3_STREAM_USE_STACK
4778 # ifndef __clang__ /* clang doesn't need additional stack space */
4779 #   define XXH3_STREAM_USE_STACK 1
4780 # endif
4781 #endif
4782 /*
4783  * Both XXH3_64bits_update and XXH3_128bits_update use this routine.
4784  */
4785 XXH_FORCE_INLINE XXH_errorcode
XXH3_update(XXH3_state_t * XXH_RESTRICT const state,const xxh_u8 * XXH_RESTRICT input,size_t len,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble)4786 XXH3_update(XXH3_state_t* XXH_RESTRICT const state,
4787             const xxh_u8* XXH_RESTRICT input, size_t len,
4788             XXH3_f_accumulate_512 f_acc512,
4789             XXH3_f_scrambleAcc f_scramble)
4790 {
4791     if (input==NULL) {
4792         XXH_ASSERT(len == 0);
4793         return XXH_OK;
4794     }
4795 
4796     XXH_ASSERT(state != NULL);
4797     {   const xxh_u8* const bEnd = input + len;
4798         const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
4799 #if defined(XXH3_STREAM_USE_STACK) && XXH3_STREAM_USE_STACK >= 1
4800         /* For some reason, gcc and MSVC seem to suffer greatly
4801          * when operating accumulators directly into state.
4802          * Operating into stack space seems to enable proper optimization.
4803          * clang, on the other hand, doesn't seem to need this trick */
4804         XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[8]; memcpy(acc, state->acc, sizeof(acc));
4805 #else
4806         xxh_u64* XXH_RESTRICT const acc = state->acc;
4807 #endif
4808         state->totalLen += len;
4809         XXH_ASSERT(state->bufferedSize <= XXH3_INTERNALBUFFER_SIZE);
4810 
4811         /* small input : just fill in tmp buffer */
4812         if (state->bufferedSize + len <= XXH3_INTERNALBUFFER_SIZE) {
4813             XXH_memcpy(state->buffer + state->bufferedSize, input, len);
4814             state->bufferedSize += (XXH32_hash_t)len;
4815             return XXH_OK;
4816         }
4817 
4818         /* total input is now > XXH3_INTERNALBUFFER_SIZE */
4819         #define XXH3_INTERNALBUFFER_STRIPES (XXH3_INTERNALBUFFER_SIZE / XXH_STRIPE_LEN)
4820         XXH_STATIC_ASSERT(XXH3_INTERNALBUFFER_SIZE % XXH_STRIPE_LEN == 0);   /* clean multiple */
4821 
4822         /*
4823          * Internal buffer is partially filled (always, except at beginning)
4824          * Complete it, then consume it.
4825          */
4826         if (state->bufferedSize) {
4827             size_t const loadSize = XXH3_INTERNALBUFFER_SIZE - state->bufferedSize;
4828             XXH_memcpy(state->buffer + state->bufferedSize, input, loadSize);
4829             input += loadSize;
4830             XXH3_consumeStripes(acc,
4831                                &state->nbStripesSoFar, state->nbStripesPerBlock,
4832                                 state->buffer, XXH3_INTERNALBUFFER_STRIPES,
4833                                 secret, state->secretLimit,
4834                                 f_acc512, f_scramble);
4835             state->bufferedSize = 0;
4836         }
4837         XXH_ASSERT(input < bEnd);
4838 
4839         /* large input to consume : ingest per full block */
4840         if ((size_t)(bEnd - input) > state->nbStripesPerBlock * XXH_STRIPE_LEN) {
4841             size_t nbStripes = (size_t)(bEnd - 1 - input) / XXH_STRIPE_LEN;
4842             XXH_ASSERT(state->nbStripesPerBlock >= state->nbStripesSoFar);
4843             /* join to current block's end */
4844             {   size_t const nbStripesToEnd = state->nbStripesPerBlock - state->nbStripesSoFar;
4845                 XXH_ASSERT(nbStripes <= nbStripes);
4846                 XXH3_accumulate(acc, input, secret + state->nbStripesSoFar * XXH_SECRET_CONSUME_RATE, nbStripesToEnd, f_acc512);
4847                 f_scramble(acc, secret + state->secretLimit);
4848                 state->nbStripesSoFar = 0;
4849                 input += nbStripesToEnd * XXH_STRIPE_LEN;
4850                 nbStripes -= nbStripesToEnd;
4851             }
4852             /* consume per entire blocks */
4853             while(nbStripes >= state->nbStripesPerBlock) {
4854                 XXH3_accumulate(acc, input, secret, state->nbStripesPerBlock, f_acc512);
4855                 f_scramble(acc, secret + state->secretLimit);
4856                 input += state->nbStripesPerBlock * XXH_STRIPE_LEN;
4857                 nbStripes -= state->nbStripesPerBlock;
4858             }
4859             /* consume last partial block */
4860             XXH3_accumulate(acc, input, secret, nbStripes, f_acc512);
4861             input += nbStripes * XXH_STRIPE_LEN;
4862             XXH_ASSERT(input < bEnd);  /* at least some bytes left */
4863             state->nbStripesSoFar = nbStripes;
4864             /* buffer predecessor of last partial stripe */
4865             XXH_memcpy(state->buffer + sizeof(state->buffer) - XXH_STRIPE_LEN, input - XXH_STRIPE_LEN, XXH_STRIPE_LEN);
4866             XXH_ASSERT(bEnd - input <= XXH_STRIPE_LEN);
4867         } else {
4868             /* content to consume <= block size */
4869             /* Consume input by a multiple of internal buffer size */
4870             if (bEnd - input > XXH3_INTERNALBUFFER_SIZE) {
4871                 const xxh_u8* const limit = bEnd - XXH3_INTERNALBUFFER_SIZE;
4872                 do {
4873                     XXH3_consumeStripes(acc,
4874                                        &state->nbStripesSoFar, state->nbStripesPerBlock,
4875                                         input, XXH3_INTERNALBUFFER_STRIPES,
4876                                         secret, state->secretLimit,
4877                                         f_acc512, f_scramble);
4878                     input += XXH3_INTERNALBUFFER_SIZE;
4879                 } while (input<limit);
4880                 /* buffer predecessor of last partial stripe */
4881                 XXH_memcpy(state->buffer + sizeof(state->buffer) - XXH_STRIPE_LEN, input - XXH_STRIPE_LEN, XXH_STRIPE_LEN);
4882             }
4883         }
4884 
4885         /* Some remaining input (always) : buffer it */
4886         XXH_ASSERT(input < bEnd);
4887         XXH_ASSERT(bEnd - input <= XXH3_INTERNALBUFFER_SIZE);
4888         XXH_ASSERT(state->bufferedSize == 0);
4889         XXH_memcpy(state->buffer, input, (size_t)(bEnd-input));
4890         state->bufferedSize = (XXH32_hash_t)(bEnd-input);
4891 #if defined(XXH3_STREAM_USE_STACK) && XXH3_STREAM_USE_STACK >= 1
4892         /* save stack accumulators into state */
4893         memcpy(state->acc, acc, sizeof(acc));
4894 #endif
4895     }
4896 
4897     return XXH_OK;
4898 }
4899 
4900 /*! @ingroup xxh3_family */
4901 XXH_PUBLIC_API XXH_errorcode
XXH3_64bits_update(XXH3_state_t * state,const void * input,size_t len)4902 XXH3_64bits_update(XXH3_state_t* state, const void* input, size_t len)
4903 {
4904     return XXH3_update(state, (const xxh_u8*)input, len,
4905                        XXH3_accumulate_512, XXH3_scrambleAcc);
4906 }
4907 
4908 
4909 XXH_FORCE_INLINE void
XXH3_digest_long(XXH64_hash_t * acc,const XXH3_state_t * state,const unsigned char * secret)4910 XXH3_digest_long (XXH64_hash_t* acc,
4911                   const XXH3_state_t* state,
4912                   const unsigned char* secret)
4913 {
4914     /*
4915      * Digest on a local copy. This way, the state remains unaltered, and it can
4916      * continue ingesting more input afterwards.
4917      */
4918     XXH_memcpy(acc, state->acc, sizeof(state->acc));
4919     if (state->bufferedSize >= XXH_STRIPE_LEN) {
4920         size_t const nbStripes = (state->bufferedSize - 1) / XXH_STRIPE_LEN;
4921         size_t nbStripesSoFar = state->nbStripesSoFar;
4922         XXH3_consumeStripes(acc,
4923                            &nbStripesSoFar, state->nbStripesPerBlock,
4924                             state->buffer, nbStripes,
4925                             secret, state->secretLimit,
4926                             XXH3_accumulate_512, XXH3_scrambleAcc);
4927         /* last stripe */
4928         XXH3_accumulate_512(acc,
4929                             state->buffer + state->bufferedSize - XXH_STRIPE_LEN,
4930                             secret + state->secretLimit - XXH_SECRET_LASTACC_START);
4931     } else {  /* bufferedSize < XXH_STRIPE_LEN */
4932         xxh_u8 lastStripe[XXH_STRIPE_LEN];
4933         size_t const catchupSize = XXH_STRIPE_LEN - state->bufferedSize;
4934         XXH_ASSERT(state->bufferedSize > 0);  /* there is always some input buffered */
4935         XXH_memcpy(lastStripe, state->buffer + sizeof(state->buffer) - catchupSize, catchupSize);
4936         XXH_memcpy(lastStripe + catchupSize, state->buffer, state->bufferedSize);
4937         XXH3_accumulate_512(acc,
4938                             lastStripe,
4939                             secret + state->secretLimit - XXH_SECRET_LASTACC_START);
4940     }
4941 }
4942 
4943 /*! @ingroup xxh3_family */
XXH3_64bits_digest(const XXH3_state_t * state)4944 XXH_PUBLIC_API XXH64_hash_t XXH3_64bits_digest (const XXH3_state_t* state)
4945 {
4946     const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
4947     if (state->totalLen > XXH3_MIDSIZE_MAX) {
4948         XXH_ALIGN(XXH_ACC_ALIGN) XXH64_hash_t acc[XXH_ACC_NB];
4949         XXH3_digest_long(acc, state, secret);
4950         return XXH3_mergeAccs(acc,
4951                               secret + XXH_SECRET_MERGEACCS_START,
4952                               (xxh_u64)state->totalLen * XXH_PRIME64_1);
4953     }
4954     /* totalLen <= XXH3_MIDSIZE_MAX: digesting a short input */
4955     if (state->useSeed)
4956         return XXH3_64bits_withSeed(state->buffer, (size_t)state->totalLen, state->seed);
4957     return XXH3_64bits_withSecret(state->buffer, (size_t)(state->totalLen),
4958                                   secret, state->secretLimit + XXH_STRIPE_LEN);
4959 }
4960 
4961 
4962 
4963 /* ==========================================
4964  * XXH3 128 bits (a.k.a XXH128)
4965  * ==========================================
4966  * XXH3's 128-bit variant has better mixing and strength than the 64-bit variant,
4967  * even without counting the significantly larger output size.
4968  *
4969  * For example, extra steps are taken to avoid the seed-dependent collisions
4970  * in 17-240 byte inputs (See XXH3_mix16B and XXH128_mix32B).
4971  *
4972  * This strength naturally comes at the cost of some speed, especially on short
4973  * lengths. Note that longer hashes are about as fast as the 64-bit version
4974  * due to it using only a slight modification of the 64-bit loop.
4975  *
4976  * XXH128 is also more oriented towards 64-bit machines. It is still extremely
4977  * fast for a _128-bit_ hash on 32-bit (it usually clears XXH64).
4978  */
4979 
4980 XXH_FORCE_INLINE XXH128_hash_t
XXH3_len_1to3_128b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)4981 XXH3_len_1to3_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
4982 {
4983     /* A doubled version of 1to3_64b with different constants. */
4984     XXH_ASSERT(input != NULL);
4985     XXH_ASSERT(1 <= len && len <= 3);
4986     XXH_ASSERT(secret != NULL);
4987     /*
4988      * len = 1: combinedl = { input[0], 0x01, input[0], input[0] }
4989      * len = 2: combinedl = { input[1], 0x02, input[0], input[1] }
4990      * len = 3: combinedl = { input[2], 0x03, input[0], input[1] }
4991      */
4992     {   xxh_u8 const c1 = input[0];
4993         xxh_u8 const c2 = input[len >> 1];
4994         xxh_u8 const c3 = input[len - 1];
4995         xxh_u32 const combinedl = ((xxh_u32)c1 <<16) | ((xxh_u32)c2 << 24)
4996                                 | ((xxh_u32)c3 << 0) | ((xxh_u32)len << 8);
4997         xxh_u32 const combinedh = XXH_rotl32(XXH_swap32(combinedl), 13);
4998         xxh_u64 const bitflipl = (XXH_readLE32(secret) ^ XXH_readLE32(secret+4)) + seed;
4999         xxh_u64 const bitfliph = (XXH_readLE32(secret+8) ^ XXH_readLE32(secret+12)) - seed;
5000         xxh_u64 const keyed_lo = (xxh_u64)combinedl ^ bitflipl;
5001         xxh_u64 const keyed_hi = (xxh_u64)combinedh ^ bitfliph;
5002         XXH128_hash_t h128;
5003         h128.low64  = XXH64_avalanche(keyed_lo);
5004         h128.high64 = XXH64_avalanche(keyed_hi);
5005         return h128;
5006     }
5007 }
5008 
5009 XXH_FORCE_INLINE XXH128_hash_t
XXH3_len_4to8_128b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)5010 XXH3_len_4to8_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5011 {
5012     XXH_ASSERT(input != NULL);
5013     XXH_ASSERT(secret != NULL);
5014     XXH_ASSERT(4 <= len && len <= 8);
5015     seed ^= (xxh_u64)XXH_swap32((xxh_u32)seed) << 32;
5016     {   xxh_u32 const input_lo = XXH_readLE32(input);
5017         xxh_u32 const input_hi = XXH_readLE32(input + len - 4);
5018         xxh_u64 const input_64 = input_lo + ((xxh_u64)input_hi << 32);
5019         xxh_u64 const bitflip = (XXH_readLE64(secret+16) ^ XXH_readLE64(secret+24)) + seed;
5020         xxh_u64 const keyed = input_64 ^ bitflip;
5021 
5022         /* Shift len to the left to ensure it is even, this avoids even multiplies. */
5023         XXH128_hash_t m128 = XXH_mult64to128(keyed, XXH_PRIME64_1 + (len << 2));
5024 
5025         m128.high64 += (m128.low64 << 1);
5026         m128.low64  ^= (m128.high64 >> 3);
5027 
5028         m128.low64   = XXH_xorshift64(m128.low64, 35);
5029         m128.low64  *= 0x9FB21C651E98DF25ULL;
5030         m128.low64   = XXH_xorshift64(m128.low64, 28);
5031         m128.high64  = XXH3_avalanche(m128.high64);
5032         return m128;
5033     }
5034 }
5035 
5036 XXH_FORCE_INLINE XXH128_hash_t
XXH3_len_9to16_128b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)5037 XXH3_len_9to16_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5038 {
5039     XXH_ASSERT(input != NULL);
5040     XXH_ASSERT(secret != NULL);
5041     XXH_ASSERT(9 <= len && len <= 16);
5042     {   xxh_u64 const bitflipl = (XXH_readLE64(secret+32) ^ XXH_readLE64(secret+40)) - seed;
5043         xxh_u64 const bitfliph = (XXH_readLE64(secret+48) ^ XXH_readLE64(secret+56)) + seed;
5044         xxh_u64 const input_lo = XXH_readLE64(input);
5045         xxh_u64       input_hi = XXH_readLE64(input + len - 8);
5046         XXH128_hash_t m128 = XXH_mult64to128(input_lo ^ input_hi ^ bitflipl, XXH_PRIME64_1);
5047         /*
5048          * Put len in the middle of m128 to ensure that the length gets mixed to
5049          * both the low and high bits in the 128x64 multiply below.
5050          */
5051         m128.low64 += (xxh_u64)(len - 1) << 54;
5052         input_hi   ^= bitfliph;
5053         /*
5054          * Add the high 32 bits of input_hi to the high 32 bits of m128, then
5055          * add the long product of the low 32 bits of input_hi and XXH_PRIME32_2 to
5056          * the high 64 bits of m128.
5057          *
5058          * The best approach to this operation is different on 32-bit and 64-bit.
5059          */
5060         if (sizeof(void *) < sizeof(xxh_u64)) { /* 32-bit */
5061             /*
5062              * 32-bit optimized version, which is more readable.
5063              *
5064              * On 32-bit, it removes an ADC and delays a dependency between the two
5065              * halves of m128.high64, but it generates an extra mask on 64-bit.
5066              */
5067             m128.high64 += (input_hi & 0xFFFFFFFF00000000ULL) + XXH_mult32to64((xxh_u32)input_hi, XXH_PRIME32_2);
5068         } else {
5069             /*
5070              * 64-bit optimized (albeit more confusing) version.
5071              *
5072              * Uses some properties of addition and multiplication to remove the mask:
5073              *
5074              * Let:
5075              *    a = input_hi.lo = (input_hi & 0x00000000FFFFFFFF)
5076              *    b = input_hi.hi = (input_hi & 0xFFFFFFFF00000000)
5077              *    c = XXH_PRIME32_2
5078              *
5079              *    a + (b * c)
5080              * Inverse Property: x + y - x == y
5081              *    a + (b * (1 + c - 1))
5082              * Distributive Property: x * (y + z) == (x * y) + (x * z)
5083              *    a + (b * 1) + (b * (c - 1))
5084              * Identity Property: x * 1 == x
5085              *    a + b + (b * (c - 1))
5086              *
5087              * Substitute a, b, and c:
5088              *    input_hi.hi + input_hi.lo + ((xxh_u64)input_hi.lo * (XXH_PRIME32_2 - 1))
5089              *
5090              * Since input_hi.hi + input_hi.lo == input_hi, we get this:
5091              *    input_hi + ((xxh_u64)input_hi.lo * (XXH_PRIME32_2 - 1))
5092              */
5093             m128.high64 += input_hi + XXH_mult32to64((xxh_u32)input_hi, XXH_PRIME32_2 - 1);
5094         }
5095         /* m128 ^= XXH_swap64(m128 >> 64); */
5096         m128.low64  ^= XXH_swap64(m128.high64);
5097 
5098         {   /* 128x64 multiply: h128 = m128 * XXH_PRIME64_2; */
5099             XXH128_hash_t h128 = XXH_mult64to128(m128.low64, XXH_PRIME64_2);
5100             h128.high64 += m128.high64 * XXH_PRIME64_2;
5101 
5102             h128.low64   = XXH3_avalanche(h128.low64);
5103             h128.high64  = XXH3_avalanche(h128.high64);
5104             return h128;
5105     }   }
5106 }
5107 
5108 /*
5109  * Assumption: `secret` size is >= XXH3_SECRET_SIZE_MIN
5110  */
5111 XXH_FORCE_INLINE XXH128_hash_t
XXH3_len_0to16_128b(const xxh_u8 * input,size_t len,const xxh_u8 * secret,XXH64_hash_t seed)5112 XXH3_len_0to16_128b(const xxh_u8* input, size_t len, const xxh_u8* secret, XXH64_hash_t seed)
5113 {
5114     XXH_ASSERT(len <= 16);
5115     {   if (len > 8) return XXH3_len_9to16_128b(input, len, secret, seed);
5116         if (len >= 4) return XXH3_len_4to8_128b(input, len, secret, seed);
5117         if (len) return XXH3_len_1to3_128b(input, len, secret, seed);
5118         {   XXH128_hash_t h128;
5119             xxh_u64 const bitflipl = XXH_readLE64(secret+64) ^ XXH_readLE64(secret+72);
5120             xxh_u64 const bitfliph = XXH_readLE64(secret+80) ^ XXH_readLE64(secret+88);
5121             h128.low64 = XXH64_avalanche(seed ^ bitflipl);
5122             h128.high64 = XXH64_avalanche( seed ^ bitfliph);
5123             return h128;
5124     }   }
5125 }
5126 
5127 /*
5128  * A bit slower than XXH3_mix16B, but handles multiply by zero better.
5129  */
5130 XXH_FORCE_INLINE XXH128_hash_t
XXH128_mix32B(XXH128_hash_t acc,const xxh_u8 * input_1,const xxh_u8 * input_2,const xxh_u8 * secret,XXH64_hash_t seed)5131 XXH128_mix32B(XXH128_hash_t acc, const xxh_u8* input_1, const xxh_u8* input_2,
5132               const xxh_u8* secret, XXH64_hash_t seed)
5133 {
5134     acc.low64  += XXH3_mix16B (input_1, secret+0, seed);
5135     acc.low64  ^= XXH_readLE64(input_2) + XXH_readLE64(input_2 + 8);
5136     acc.high64 += XXH3_mix16B (input_2, secret+16, seed);
5137     acc.high64 ^= XXH_readLE64(input_1) + XXH_readLE64(input_1 + 8);
5138     return acc;
5139 }
5140 
5141 
5142 XXH_FORCE_INLINE XXH128_hash_t
XXH3_len_17to128_128b(const xxh_u8 * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH64_hash_t seed)5143 XXH3_len_17to128_128b(const xxh_u8* XXH_RESTRICT input, size_t len,
5144                       const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5145                       XXH64_hash_t seed)
5146 {
5147     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
5148     XXH_ASSERT(16 < len && len <= 128);
5149 
5150     {   XXH128_hash_t acc;
5151         acc.low64 = len * XXH_PRIME64_1;
5152         acc.high64 = 0;
5153         if (len > 32) {
5154             if (len > 64) {
5155                 if (len > 96) {
5156                     acc = XXH128_mix32B(acc, input+48, input+len-64, secret+96, seed);
5157                 }
5158                 acc = XXH128_mix32B(acc, input+32, input+len-48, secret+64, seed);
5159             }
5160             acc = XXH128_mix32B(acc, input+16, input+len-32, secret+32, seed);
5161         }
5162         acc = XXH128_mix32B(acc, input, input+len-16, secret, seed);
5163         {   XXH128_hash_t h128;
5164             h128.low64  = acc.low64 + acc.high64;
5165             h128.high64 = (acc.low64    * XXH_PRIME64_1)
5166                         + (acc.high64   * XXH_PRIME64_4)
5167                         + ((len - seed) * XXH_PRIME64_2);
5168             h128.low64  = XXH3_avalanche(h128.low64);
5169             h128.high64 = (XXH64_hash_t)0 - XXH3_avalanche(h128.high64);
5170             return h128;
5171         }
5172     }
5173 }
5174 
5175 XXH_NO_INLINE XXH128_hash_t
XXH3_len_129to240_128b(const xxh_u8 * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH64_hash_t seed)5176 XXH3_len_129to240_128b(const xxh_u8* XXH_RESTRICT input, size_t len,
5177                        const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5178                        XXH64_hash_t seed)
5179 {
5180     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN); (void)secretSize;
5181     XXH_ASSERT(128 < len && len <= XXH3_MIDSIZE_MAX);
5182 
5183     {   XXH128_hash_t acc;
5184         int const nbRounds = (int)len / 32;
5185         int i;
5186         acc.low64 = len * XXH_PRIME64_1;
5187         acc.high64 = 0;
5188         for (i=0; i<4; i++) {
5189             acc = XXH128_mix32B(acc,
5190                                 input  + (32 * i),
5191                                 input  + (32 * i) + 16,
5192                                 secret + (32 * i),
5193                                 seed);
5194         }
5195         acc.low64 = XXH3_avalanche(acc.low64);
5196         acc.high64 = XXH3_avalanche(acc.high64);
5197         XXH_ASSERT(nbRounds >= 4);
5198         for (i=4 ; i < nbRounds; i++) {
5199             acc = XXH128_mix32B(acc,
5200                                 input + (32 * i),
5201                                 input + (32 * i) + 16,
5202                                 secret + XXH3_MIDSIZE_STARTOFFSET + (32 * (i - 4)),
5203                                 seed);
5204         }
5205         /* last bytes */
5206         acc = XXH128_mix32B(acc,
5207                             input + len - 16,
5208                             input + len - 32,
5209                             secret + XXH3_SECRET_SIZE_MIN - XXH3_MIDSIZE_LASTOFFSET - 16,
5210                             0ULL - seed);
5211 
5212         {   XXH128_hash_t h128;
5213             h128.low64  = acc.low64 + acc.high64;
5214             h128.high64 = (acc.low64    * XXH_PRIME64_1)
5215                         + (acc.high64   * XXH_PRIME64_4)
5216                         + ((len - seed) * XXH_PRIME64_2);
5217             h128.low64  = XXH3_avalanche(h128.low64);
5218             h128.high64 = (XXH64_hash_t)0 - XXH3_avalanche(h128.high64);
5219             return h128;
5220         }
5221     }
5222 }
5223 
5224 XXH_FORCE_INLINE XXH128_hash_t
XXH3_hashLong_128b_internal(const void * XXH_RESTRICT input,size_t len,const xxh_u8 * XXH_RESTRICT secret,size_t secretSize,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble)5225 XXH3_hashLong_128b_internal(const void* XXH_RESTRICT input, size_t len,
5226                             const xxh_u8* XXH_RESTRICT secret, size_t secretSize,
5227                             XXH3_f_accumulate_512 f_acc512,
5228                             XXH3_f_scrambleAcc f_scramble)
5229 {
5230     XXH_ALIGN(XXH_ACC_ALIGN) xxh_u64 acc[XXH_ACC_NB] = XXH3_INIT_ACC;
5231 
5232     XXH3_hashLong_internal_loop(acc, (const xxh_u8*)input, len, secret, secretSize, f_acc512, f_scramble);
5233 
5234     /* converge into final hash */
5235     XXH_STATIC_ASSERT(sizeof(acc) == 64);
5236     XXH_ASSERT(secretSize >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
5237     {   XXH128_hash_t h128;
5238         h128.low64  = XXH3_mergeAccs(acc,
5239                                      secret + XXH_SECRET_MERGEACCS_START,
5240                                      (xxh_u64)len * XXH_PRIME64_1);
5241         h128.high64 = XXH3_mergeAccs(acc,
5242                                      secret + secretSize
5243                                             - sizeof(acc) - XXH_SECRET_MERGEACCS_START,
5244                                      ~((xxh_u64)len * XXH_PRIME64_2));
5245         return h128;
5246     }
5247 }
5248 
5249 /*
5250  * It's important for performance that XXH3_hashLong is not inlined.
5251  */
5252 XXH_NO_INLINE XXH128_hash_t
XXH3_hashLong_128b_default(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,const void * XXH_RESTRICT secret,size_t secretLen)5253 XXH3_hashLong_128b_default(const void* XXH_RESTRICT input, size_t len,
5254                            XXH64_hash_t seed64,
5255                            const void* XXH_RESTRICT secret, size_t secretLen)
5256 {
5257     (void)seed64; (void)secret; (void)secretLen;
5258     return XXH3_hashLong_128b_internal(input, len, XXH3_kSecret, sizeof(XXH3_kSecret),
5259                                        XXH3_accumulate_512, XXH3_scrambleAcc);
5260 }
5261 
5262 /*
5263  * It's important for performance to pass @secretLen (when it's static)
5264  * to the compiler, so that it can properly optimize the vectorized loop.
5265  */
5266 XXH_FORCE_INLINE XXH128_hash_t
XXH3_hashLong_128b_withSecret(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,const void * XXH_RESTRICT secret,size_t secretLen)5267 XXH3_hashLong_128b_withSecret(const void* XXH_RESTRICT input, size_t len,
5268                               XXH64_hash_t seed64,
5269                               const void* XXH_RESTRICT secret, size_t secretLen)
5270 {
5271     (void)seed64;
5272     return XXH3_hashLong_128b_internal(input, len, (const xxh_u8*)secret, secretLen,
5273                                        XXH3_accumulate_512, XXH3_scrambleAcc);
5274 }
5275 
5276 XXH_FORCE_INLINE XXH128_hash_t
XXH3_hashLong_128b_withSeed_internal(const void * XXH_RESTRICT input,size_t len,XXH64_hash_t seed64,XXH3_f_accumulate_512 f_acc512,XXH3_f_scrambleAcc f_scramble,XXH3_f_initCustomSecret f_initSec)5277 XXH3_hashLong_128b_withSeed_internal(const void* XXH_RESTRICT input, size_t len,
5278                                 XXH64_hash_t seed64,
5279                                 XXH3_f_accumulate_512 f_acc512,
5280                                 XXH3_f_scrambleAcc f_scramble,
5281                                 XXH3_f_initCustomSecret f_initSec)
5282 {
5283     if (seed64 == 0)
5284         return XXH3_hashLong_128b_internal(input, len,
5285                                            XXH3_kSecret, sizeof(XXH3_kSecret),
5286                                            f_acc512, f_scramble);
5287     {   XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
5288         f_initSec(secret, seed64);
5289         return XXH3_hashLong_128b_internal(input, len, (const xxh_u8*)secret, sizeof(secret),
5290                                            f_acc512, f_scramble);
5291     }
5292 }
5293 
5294 /*
5295  * It's important for performance that XXH3_hashLong is not inlined.
5296  */
5297 XXH_NO_INLINE XXH128_hash_t
XXH3_hashLong_128b_withSeed(const void * input,size_t len,XXH64_hash_t seed64,const void * XXH_RESTRICT secret,size_t secretLen)5298 XXH3_hashLong_128b_withSeed(const void* input, size_t len,
5299                             XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen)
5300 {
5301     (void)secret; (void)secretLen;
5302     return XXH3_hashLong_128b_withSeed_internal(input, len, seed64,
5303                 XXH3_accumulate_512, XXH3_scrambleAcc, XXH3_initCustomSecret);
5304 }
5305 
5306 typedef XXH128_hash_t (*XXH3_hashLong128_f)(const void* XXH_RESTRICT, size_t,
5307                                             XXH64_hash_t, const void* XXH_RESTRICT, size_t);
5308 
5309 XXH_FORCE_INLINE XXH128_hash_t
XXH3_128bits_internal(const void * input,size_t len,XXH64_hash_t seed64,const void * XXH_RESTRICT secret,size_t secretLen,XXH3_hashLong128_f f_hl128)5310 XXH3_128bits_internal(const void* input, size_t len,
5311                       XXH64_hash_t seed64, const void* XXH_RESTRICT secret, size_t secretLen,
5312                       XXH3_hashLong128_f f_hl128)
5313 {
5314     XXH_ASSERT(secretLen >= XXH3_SECRET_SIZE_MIN);
5315     /*
5316      * If an action is to be taken if `secret` conditions are not respected,
5317      * it should be done here.
5318      * For now, it's a contract pre-condition.
5319      * Adding a check and a branch here would cost performance at every hash.
5320      */
5321     if (len <= 16)
5322         return XXH3_len_0to16_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, seed64);
5323     if (len <= 128)
5324         return XXH3_len_17to128_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
5325     if (len <= XXH3_MIDSIZE_MAX)
5326         return XXH3_len_129to240_128b((const xxh_u8*)input, len, (const xxh_u8*)secret, secretLen, seed64);
5327     return f_hl128(input, len, seed64, secret, secretLen);
5328 }
5329 
5330 
5331 /* ===   Public XXH128 API   === */
5332 
5333 /*! @ingroup xxh3_family */
XXH3_128bits(const void * input,size_t len)5334 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits(const void* input, size_t len)
5335 {
5336     return XXH3_128bits_internal(input, len, 0,
5337                                  XXH3_kSecret, sizeof(XXH3_kSecret),
5338                                  XXH3_hashLong_128b_default);
5339 }
5340 
5341 /*! @ingroup xxh3_family */
5342 XXH_PUBLIC_API XXH128_hash_t
XXH3_128bits_withSecret(const void * input,size_t len,const void * secret,size_t secretSize)5343 XXH3_128bits_withSecret(const void* input, size_t len, const void* secret, size_t secretSize)
5344 {
5345     return XXH3_128bits_internal(input, len, 0,
5346                                  (const xxh_u8*)secret, secretSize,
5347                                  XXH3_hashLong_128b_withSecret);
5348 }
5349 
5350 /*! @ingroup xxh3_family */
5351 XXH_PUBLIC_API XXH128_hash_t
XXH3_128bits_withSeed(const void * input,size_t len,XXH64_hash_t seed)5352 XXH3_128bits_withSeed(const void* input, size_t len, XXH64_hash_t seed)
5353 {
5354     return XXH3_128bits_internal(input, len, seed,
5355                                  XXH3_kSecret, sizeof(XXH3_kSecret),
5356                                  XXH3_hashLong_128b_withSeed);
5357 }
5358 
5359 /*! @ingroup xxh3_family */
5360 XXH_PUBLIC_API XXH128_hash_t
XXH3_128bits_withSecretandSeed(const void * input,size_t len,const void * secret,size_t secretSize,XXH64_hash_t seed)5361 XXH3_128bits_withSecretandSeed(const void* input, size_t len, const void* secret, size_t secretSize, XXH64_hash_t seed)
5362 {
5363     if (len <= XXH3_MIDSIZE_MAX)
5364         return XXH3_128bits_internal(input, len, seed, XXH3_kSecret, sizeof(XXH3_kSecret), NULL);
5365     return XXH3_hashLong_128b_withSecret(input, len, seed, secret, secretSize);
5366 }
5367 
5368 /*! @ingroup xxh3_family */
5369 XXH_PUBLIC_API XXH128_hash_t
XXH128(const void * input,size_t len,XXH64_hash_t seed)5370 XXH128(const void* input, size_t len, XXH64_hash_t seed)
5371 {
5372     return XXH3_128bits_withSeed(input, len, seed);
5373 }
5374 
5375 
5376 /* ===   XXH3 128-bit streaming   === */
5377 
5378 /*
5379  * All initialization and update functions are identical to 64-bit streaming variant.
5380  * The only difference is the finalization routine.
5381  */
5382 
5383 /*! @ingroup xxh3_family */
5384 XXH_PUBLIC_API XXH_errorcode
XXH3_128bits_reset(XXH3_state_t * statePtr)5385 XXH3_128bits_reset(XXH3_state_t* statePtr)
5386 {
5387     return XXH3_64bits_reset(statePtr);
5388 }
5389 
5390 /*! @ingroup xxh3_family */
5391 XXH_PUBLIC_API XXH_errorcode
XXH3_128bits_reset_withSecret(XXH3_state_t * statePtr,const void * secret,size_t secretSize)5392 XXH3_128bits_reset_withSecret(XXH3_state_t* statePtr, const void* secret, size_t secretSize)
5393 {
5394     return XXH3_64bits_reset_withSecret(statePtr, secret, secretSize);
5395 }
5396 
5397 /*! @ingroup xxh3_family */
5398 XXH_PUBLIC_API XXH_errorcode
XXH3_128bits_reset_withSeed(XXH3_state_t * statePtr,XXH64_hash_t seed)5399 XXH3_128bits_reset_withSeed(XXH3_state_t* statePtr, XXH64_hash_t seed)
5400 {
5401     return XXH3_64bits_reset_withSeed(statePtr, seed);
5402 }
5403 
5404 /*! @ingroup xxh3_family */
5405 XXH_PUBLIC_API XXH_errorcode
XXH3_128bits_reset_withSecretandSeed(XXH3_state_t * statePtr,const void * secret,size_t secretSize,XXH64_hash_t seed)5406 XXH3_128bits_reset_withSecretandSeed(XXH3_state_t* statePtr, const void* secret, size_t secretSize, XXH64_hash_t seed)
5407 {
5408     return XXH3_64bits_reset_withSecretandSeed(statePtr, secret, secretSize, seed);
5409 }
5410 
5411 /*! @ingroup xxh3_family */
5412 XXH_PUBLIC_API XXH_errorcode
XXH3_128bits_update(XXH3_state_t * state,const void * input,size_t len)5413 XXH3_128bits_update(XXH3_state_t* state, const void* input, size_t len)
5414 {
5415     return XXH3_update(state, (const xxh_u8*)input, len,
5416                        XXH3_accumulate_512, XXH3_scrambleAcc);
5417 }
5418 
5419 /*! @ingroup xxh3_family */
XXH3_128bits_digest(const XXH3_state_t * state)5420 XXH_PUBLIC_API XXH128_hash_t XXH3_128bits_digest (const XXH3_state_t* state)
5421 {
5422     const unsigned char* const secret = (state->extSecret == NULL) ? state->customSecret : state->extSecret;
5423     if (state->totalLen > XXH3_MIDSIZE_MAX) {
5424         XXH_ALIGN(XXH_ACC_ALIGN) XXH64_hash_t acc[XXH_ACC_NB];
5425         XXH3_digest_long(acc, state, secret);
5426         XXH_ASSERT(state->secretLimit + XXH_STRIPE_LEN >= sizeof(acc) + XXH_SECRET_MERGEACCS_START);
5427         {   XXH128_hash_t h128;
5428             h128.low64  = XXH3_mergeAccs(acc,
5429                                          secret + XXH_SECRET_MERGEACCS_START,
5430                                          (xxh_u64)state->totalLen * XXH_PRIME64_1);
5431             h128.high64 = XXH3_mergeAccs(acc,
5432                                          secret + state->secretLimit + XXH_STRIPE_LEN
5433                                                 - sizeof(acc) - XXH_SECRET_MERGEACCS_START,
5434                                          ~((xxh_u64)state->totalLen * XXH_PRIME64_2));
5435             return h128;
5436         }
5437     }
5438     /* len <= XXH3_MIDSIZE_MAX : short code */
5439     if (state->seed)
5440         return XXH3_128bits_withSeed(state->buffer, (size_t)state->totalLen, state->seed);
5441     return XXH3_128bits_withSecret(state->buffer, (size_t)(state->totalLen),
5442                                    secret, state->secretLimit + XXH_STRIPE_LEN);
5443 }
5444 
5445 /* 128-bit utility functions */
5446 
5447 #include <string.h>   /* memcmp, memcpy */
5448 
5449 /* return : 1 is equal, 0 if different */
5450 /*! @ingroup xxh3_family */
XXH128_isEqual(XXH128_hash_t h1,XXH128_hash_t h2)5451 XXH_PUBLIC_API int XXH128_isEqual(XXH128_hash_t h1, XXH128_hash_t h2)
5452 {
5453     /* note : XXH128_hash_t is compact, it has no padding byte */
5454     return !(memcmp(&h1, &h2, sizeof(h1)));
5455 }
5456 
5457 /* This prototype is compatible with stdlib's qsort().
5458  * return : >0 if *h128_1  > *h128_2
5459  *          <0 if *h128_1  < *h128_2
5460  *          =0 if *h128_1 == *h128_2  */
5461 /*! @ingroup xxh3_family */
XXH128_cmp(const void * h128_1,const void * h128_2)5462 XXH_PUBLIC_API int XXH128_cmp(const void* h128_1, const void* h128_2)
5463 {
5464     XXH128_hash_t const h1 = *(const XXH128_hash_t*)h128_1;
5465     XXH128_hash_t const h2 = *(const XXH128_hash_t*)h128_2;
5466     int const hcmp = (h1.high64 > h2.high64) - (h2.high64 > h1.high64);
5467     /* note : bets that, in most cases, hash values are different */
5468     if (hcmp) return hcmp;
5469     return (h1.low64 > h2.low64) - (h2.low64 > h1.low64);
5470 }
5471 
5472 
5473 /*======   Canonical representation   ======*/
5474 /*! @ingroup xxh3_family */
5475 XXH_PUBLIC_API void
XXH128_canonicalFromHash(XXH128_canonical_t * dst,XXH128_hash_t hash)5476 XXH128_canonicalFromHash(XXH128_canonical_t* dst, XXH128_hash_t hash)
5477 {
5478     XXH_STATIC_ASSERT(sizeof(XXH128_canonical_t) == sizeof(XXH128_hash_t));
5479     if (XXH_CPU_LITTLE_ENDIAN) {
5480         hash.high64 = XXH_swap64(hash.high64);
5481         hash.low64  = XXH_swap64(hash.low64);
5482     }
5483     XXH_memcpy(dst, &hash.high64, sizeof(hash.high64));
5484     XXH_memcpy((char*)dst + sizeof(hash.high64), &hash.low64, sizeof(hash.low64));
5485 }
5486 
5487 /*! @ingroup xxh3_family */
5488 XXH_PUBLIC_API XXH128_hash_t
XXH128_hashFromCanonical(const XXH128_canonical_t * src)5489 XXH128_hashFromCanonical(const XXH128_canonical_t* src)
5490 {
5491     XXH128_hash_t h;
5492     h.high64 = XXH_readBE64(src);
5493     h.low64  = XXH_readBE64(src->digest + 8);
5494     return h;
5495 }
5496 
5497 
5498 
5499 /* ==========================================
5500  * Secret generators
5501  * ==========================================
5502  */
5503 #define XXH_MIN(x, y) (((x) > (y)) ? (y) : (x))
5504 
XXH3_combine16(void * dst,XXH128_hash_t h128)5505 static void XXH3_combine16(void* dst, XXH128_hash_t h128)
5506 {
5507     XXH_writeLE64( dst, XXH_readLE64(dst) ^ h128.low64 );
5508     XXH_writeLE64( (char*)dst+8, XXH_readLE64((char*)dst+8) ^ h128.high64 );
5509 }
5510 
5511 /*! @ingroup xxh3_family */
5512 XXH_PUBLIC_API XXH_errorcode
XXH3_generateSecret(void * secretBuffer,size_t secretSize,const void * customSeed,size_t customSeedSize)5513 XXH3_generateSecret(void* secretBuffer, size_t secretSize, const void* customSeed, size_t customSeedSize)
5514 {
5515     XXH_ASSERT(secretBuffer != NULL);
5516     if (secretBuffer == NULL) return XXH_ERROR;
5517     XXH_ASSERT(secretSize >= XXH3_SECRET_SIZE_MIN);
5518     if (secretSize < XXH3_SECRET_SIZE_MIN) return XXH_ERROR;
5519     if (customSeedSize == 0) {
5520         customSeed = XXH3_kSecret;
5521         customSeedSize = XXH_SECRET_DEFAULT_SIZE;
5522     }
5523     XXH_ASSERT(customSeed != NULL);
5524     if (customSeed == NULL) return XXH_ERROR;
5525 
5526     /* Fill secretBuffer with a copy of customSeed - repeat as needed */
5527     {   size_t pos = 0;
5528         while (pos < secretSize) {
5529             size_t const toCopy = XXH_MIN((secretSize - pos), customSeedSize);
5530             memcpy((char*)secretBuffer + pos, customSeed, toCopy);
5531             pos += toCopy;
5532     }   }
5533 
5534     {   size_t const nbSeg16 = secretSize / 16;
5535         size_t n;
5536         XXH128_canonical_t scrambler;
5537         XXH128_canonicalFromHash(&scrambler, XXH128(customSeed, customSeedSize, 0));
5538         for (n=0; n<nbSeg16; n++) {
5539             XXH128_hash_t const h128 = XXH128(&scrambler, sizeof(scrambler), n);
5540             XXH3_combine16((char*)secretBuffer + n*16, h128);
5541         }
5542         /* last segment */
5543         XXH3_combine16((char*)secretBuffer + secretSize - 16, XXH128_hashFromCanonical(&scrambler));
5544     }
5545     return XXH_OK;
5546 }
5547 
5548 /*! @ingroup xxh3_family */
5549 XXH_PUBLIC_API void
XXH3_generateSecret_fromSeed(void * secretBuffer,XXH64_hash_t seed)5550 XXH3_generateSecret_fromSeed(void* secretBuffer, XXH64_hash_t seed)
5551 {
5552     XXH_ALIGN(XXH_SEC_ALIGN) xxh_u8 secret[XXH_SECRET_DEFAULT_SIZE];
5553     XXH3_initCustomSecret(secret, seed);
5554     XXH_ASSERT(secretBuffer != NULL);
5555     memcpy(secretBuffer, secret, XXH_SECRET_DEFAULT_SIZE);
5556 }
5557 
5558 
5559 
5560 /* Pop our optimization override from above */
5561 #if XXH_VECTOR == XXH_AVX2 /* AVX2 */ \
5562   && defined(__GNUC__) && !defined(__clang__) /* GCC, not Clang */ \
5563   && defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) /* respect -O0 and -Os */
5564 #  pragma GCC pop_options
5565 #endif
5566 
5567 #endif  /* XXH_NO_LONG_LONG */
5568 
5569 #endif  /* XXH_NO_XXH3 */
5570 
5571 /*!
5572  * @}
5573  */
5574 #endif  /* XXH_IMPLEMENTATION */
5575 
5576 
5577 #if defined (__cplusplus)
5578 }
5579 #endif
5580