1 | /* insert_string_sse -- insert_string variant using SSE4.2's CRC instructions |
2 | * |
3 | * Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler |
4 | * For conditions of distribution and use, see copyright notice in zlib.h |
5 | * |
6 | */ |
7 | |
8 | #include "../../zbuild.h" |
9 | #include <immintrin.h> |
10 | #ifdef _MSC_VER |
11 | # include <nmmintrin.h> |
12 | #endif |
13 | #include "../../deflate.h" |
14 | |
15 | /* =========================================================================== |
16 | * Insert string str in the dictionary and set match_head to the previous head |
17 | * of the hash chain (the most recent string with same hash key). Return |
18 | * the previous length of the hash chain. |
19 | * IN assertion: all calls to to INSERT_STRING are made with consecutive |
20 | * input characters and the first MIN_MATCH bytes of str are valid |
21 | * (except for the last MIN_MATCH-1 bytes of the input file). |
22 | */ |
23 | #ifdef X86_SSE42_CRC_HASH |
24 | ZLIB_INTERNAL Pos insert_string_sse(deflate_state *const s, const Pos str, unsigned int count) { |
25 | Pos ret = 0; |
26 | unsigned int idx; |
27 | unsigned int *ip, val, h; |
28 | |
29 | for (idx = 0; idx < count; idx++) { |
30 | ip = (unsigned *)&s->window[str+idx]; |
31 | memcpy(&val, ip, sizeof(val)); |
32 | h = 0; |
33 | |
34 | if (s->level >= TRIGGER_LEVEL) |
35 | val &= 0xFFFFFF; |
36 | |
37 | #if defined(X86_SSE42_CRC_INTRIN) |
38 | # ifdef _MSC_VER |
39 | h = _mm_crc32_u32(h, val); |
40 | # else |
41 | h = __builtin_ia32_crc32si(h, val); |
42 | # endif |
43 | #else |
44 | # ifdef _MSC_VER |
45 | __asm { |
46 | mov edx, h |
47 | mov eax, val |
48 | crc32 eax, edx |
49 | mov val, eax |
50 | }; |
51 | # else |
52 | __asm__ __volatile__ ( |
53 | "crc32 %1,%0\n\t" |
54 | : "+r" (h) |
55 | : "r" (val) |
56 | ); |
57 | # endif |
58 | #endif |
59 | Pos head = s->head[h & s->hash_mask]; |
60 | if (head != str+idx) { |
61 | s->prev[(str+idx) & s->w_mask] = head; |
62 | s->head[h & s->hash_mask] = str+idx; |
63 | if (idx == count-1) |
64 | ret = head; |
65 | } else if (idx == count - 1) { |
66 | ret = str + idx; |
67 | } |
68 | } |
69 | return ret; |
70 | } |
71 | #endif |
72 | |