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author | David Robillard <d@drobilla.net> | 2018-06-06 20:35:46 +0200 |
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committer | David Robillard <d@drobilla.net> | 2019-04-13 19:15:32 +0200 |
commit | 3d1d75d570579c402f9462f7b3048560651ac582 (patch) | |
tree | ae7cf3e2c79aad80db94fc04a45e3310e9c8d4c9 /src/zix/digest.c | |
parent | aeeb845013778542afe838c172e1e1bb800c68eb (diff) | |
download | serd-3d1d75d570579c402f9462f7b3048560651ac582.tar.gz serd-3d1d75d570579c402f9462f7b3048560651ac582.tar.bz2 serd-3d1d75d570579c402f9462f7b3048560651ac582.zip |
Add zix data structures for use in model
Diffstat (limited to 'src/zix/digest.c')
-rw-r--r-- | src/zix/digest.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/src/zix/digest.c b/src/zix/digest.c new file mode 100644 index 00000000..7d9c0352 --- /dev/null +++ b/src/zix/digest.c @@ -0,0 +1,57 @@ +/* + Copyright 2012-2014 David Robillard <http://drobilla.net> + + Permission to use, copy, modify, and/or distribute this software for any + purpose with or without fee is hereby granted, provided that the above + copyright notice and this permission notice appear in all copies. + + THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +*/ + +#include "zix/digest.h" + +#ifdef __SSE4_2__ +# include <smmintrin.h> +#endif + +ZIX_API uint32_t +zix_digest_start(void) +{ +#ifdef __SSE4_2__ + return 1; // CRC32 initial value +#else + return 5381; // DJB hash initial value +#endif +} + +ZIX_API uint32_t +zix_digest_add(uint32_t hash, const void* const buf, const size_t len) +{ + const uint8_t* str = (const uint8_t*)buf; +#ifdef __SSE4_2__ + // SSE 4.2 CRC32 + for (size_t i = 0; i < (len / sizeof(uint32_t)); ++i) { + hash = _mm_crc32_u32(hash, *(const uint32_t*)str); + str += sizeof(uint32_t); + } + if (len & sizeof(uint16_t)) { + hash = _mm_crc32_u16(hash, *(const uint16_t*)str); + str += sizeof(uint16_t); + } + if (len & sizeof(uint8_t)) { + hash = _mm_crc32_u8(hash, *(const uint8_t*)str); + } +#else + // Classic DJB hash + for (size_t i = 0; i < len; ++i) { + hash = (hash << 5) + hash + str[i]; + } +#endif + return hash; +} |