mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-10-01 06:00:49 +00:00
51 lines
1.5 KiB
C
51 lines
1.5 KiB
C
|
/* insert_string_sse -- insert_string variant using SSE4.2's CRC instructions
|
||
|
|
*
|
||
|
|
* Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
|
||
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "deflate.h"
|
||
|
|
|
||
|
|
/* ===========================================================================
|
||
|
|
* Insert string str in the dictionary and set match_head to the previous head
|
||
|
|
* of the hash chain (the most recent string with same hash key). Return
|
||
|
|
* the previous length of the hash chain.
|
||
|
|
* IN assertion: all calls to to INSERT_STRING are made with consecutive
|
||
|
|
* input characters and the first MIN_MATCH bytes of str are valid
|
||
|
|
* (except for the last MIN_MATCH-1 bytes of the input file).
|
||
|
|
*/
|
||
|
|
#ifdef X86_SSE4_2_CRC_HASH
|
||
|
|
Pos insert_string_sse(deflate_state *const s, const Pos str, unsigned int count) {
|
||
|
|
Pos ret = 0;
|
||
|
|
unsigned int idx;
|
||
|
|
unsigned *ip, val, h = 0;
|
||
|
|
|
||
|
|
for (idx = 0; idx < count; idx++) {
|
||
|
|
ip = (unsigned *)&s->window[str+idx];
|
||
|
|
val = *ip;
|
||
|
|
h = 0;
|
||
|
|
|
||
|
|
if (s->level >= 6)
|
||
|
|
val &= 0xFFFFFF;
|
||
|
|
|
||
|
|
#ifdef _MSC_VER
|
||
|
|
h = _mm_crc32_u32(h, val);
|
||
|
|
#else
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"crc32 %1,%0\n\t"
|
||
|
|
: "+r" (h)
|
||
|
|
: "r" (val)
|
||
|
|
);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (s->head[h & s->hash_mask] != str+idx) {
|
||
|
|
s->prev[(str+idx) & s->w_mask] = s->head[h & s->hash_mask];
|
||
|
|
s->head[h & s->hash_mask] = str+idx;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
ret = s->prev[(str+count-1) & s->w_mask];
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
#endif
|