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Comparing liblzf/lzf_c.c (file contents):
Revision 1.10 by root, Thu Apr 14 20:38:50 2005 UTC vs.
Revision 1.15 by root, Fri Nov 2 12:39:20 2007 UTC

1/* 1/*
2 * Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de> 2 * Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de>
3 * 3 *
4 * Redistribution and use in source and binary forms, with or without modifica- 4 * Redistribution and use in source and binary forms, with or without modifica-
5 * tion, are permitted provided that the following conditions are met: 5 * tion, are permitted provided that the following conditions are met:
6 * 6 *
7 * 1. Redistributions of source code must retain the above copyright notice, 7 * 1. Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer. 8 * this list of conditions and the following disclaimer.
9 * 9 *
10 * 2. Redistributions in binary form must reproduce the above copyright 10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the 11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution. 12 * documentation and/or other materials provided with the distribution.
13 *
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 * 13 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- 17 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
… …
48 */ 45 */
49#ifndef FRST 46#ifndef FRST
50# define FRST(p) (((p[0]) << 8) | p[1]) 47# define FRST(p) (((p[0]) << 8) | p[1])
51# define NEXT(v,p) (((v) << 8) | p[2]) 48# define NEXT(v,p) (((v) << 8) | p[2])
52# define IDX(h) ((((h ^ (h << 5)) >> (3*8 - HLOG)) - h*5) & (HSIZE - 1)) 49# define IDX(h) ((((h ^ (h << 5)) >> (3*8 - HLOG)) - h*5) & (HSIZE - 1))
50/*# define IDX(h) ((ip[0] * 121 ^ ip[1] * 33 ^ ip[2] * 1) & (HSIZE-1))*/
53#endif 51#endif
54/* 52/*
55 * IDX works because it is very similar to a multiplicative hash, e.g. 53 * IDX works because it is very similar to a multiplicative hash, e.g.
56 * ((h * 57321 >> (3*8 - HLOG)) & (HSIZE - 1)) 54 * ((h * 57321 >> (3*8 - HLOG)) & (HSIZE - 1))
57 * the latter is also quite fast on newer CPUs, and sligthly better 55 * the latter is also quite fast on newer CPUs, and compresses similarly.
58 * 56 *
59 * the next one is also quite good, albeit slow ;) 57 * the next one is also quite good, albeit slow ;)
60 * (int)(cos(h & 0xffffff) * 1e6) 58 * (int)(cos(h & 0xffffff) * 1e6)
61 */ 59 */
62 60
… …
67# define IDX(h) ((h) & (HSIZE - 1)) 65# define IDX(h) ((h) & (HSIZE - 1))
68#endif 66#endif
69 67
70#define MAX_LIT (1 << 5) 68#define MAX_LIT (1 << 5)
71#define MAX_OFF (1 << 13) 69#define MAX_OFF (1 << 13)
72#define MAX_REF ((1 << 8) + (1 << 3)) 70#define MAX_REF ((1 << 8) + (1 << 3))
71
72#if (__i386 || __amd64) && __GNUC__ >= 3
73# define lzf_movsb(dst, src, len) \
74 asm ("rep movsb" \
75 : "=D" (dst), "=S" (src), "=c" (len) \
76 : "0" (dst), "1" (src), "2" (len));
77#endif
73 78
74/* 79/*
75 * compressed format 80 * compressed format
76 * 81 *
77 * 000LLLLL <L+1> ; literal 82 * 000LLLLL <L+1> ; literal
… …
82 87
83unsigned int 88unsigned int
84lzf_compress (const void *const in_data, unsigned int in_len, 89lzf_compress (const void *const in_data, unsigned int in_len,
85 void *out_data, unsigned int out_len 90 void *out_data, unsigned int out_len
86#if LZF_STATE_ARG 91#if LZF_STATE_ARG
87 , LZF_STATE *htab 92 , LZF_STATE htab
88#endif 93#endif
89 ) 94 )
90{ 95{
91#if !LZF_STATE_ARG 96#if !LZF_STATE_ARG
92 LZF_STATE htab; 97 LZF_STATE htab;
… …
101 unsigned int hval = FRST (ip); 106 unsigned int hval = FRST (ip);
102 unsigned long off; 107 unsigned long off;
103 int lit = 0; 108 int lit = 0;
104 109
105#if INIT_HTAB 110#if INIT_HTAB
106# if USE_MEMCPY
107 memset (htab, 0, sizeof (htab)); 111 memset (htab, 0, sizeof (htab));
108# else 112# if 0
109 for (hslot = htab; hslot < htab + HSIZE; hslot++) 113 for (hslot = htab; hslot < htab + HSIZE; hslot++)
110 *hslot++ = ip; 114 *hslot++ = ip;
111# endif 115# endif
112#endif 116#endif
113 117
114 for (;;) 118 for (;;)
115 { 119 {
… …
211 { 215 {
212 if (op + 1 + MAX_LIT >= out_end) 216 if (op + 1 + MAX_LIT >= out_end)
213 return 0; 217 return 0;
214 218
215 *op++ = MAX_LIT - 1; 219 *op++ = MAX_LIT - 1;
216#if USE_MEMCPY 220
217 memcpy (op, ip - MAX_LIT, MAX_LIT); 221#ifdef lzf_movsb
218 op += MAX_LIT; 222 ip -= lit;
219 lit = 0; 223 lzf_movsb (op, ip, lit);
220#else 224#else
221 lit = -lit; 225 lit = -lit;
222 do 226 do
223 *op++ = ip[lit]; 227 *op++ = ip[lit];
224 while (++lit); 228 while (++lit);
… …
230 { 234 {
231 if (op + lit + 1 >= out_end) 235 if (op + lit + 1 >= out_end)
232 return 0; 236 return 0;
233 237
234 *op++ = lit - 1; 238 *op++ = lit - 1;
239#ifdef lzf_movsb
240 ip -= lit;
241 lzf_movsb (op, ip, lit);
242#else
235 lit = -lit; 243 lit = -lit;
236 do 244 do
237 *op++ = ip[lit]; 245 *op++ = ip[lit];
238 while (++lit); 246 while (++lit);
247#endif
239 } 248 }
240 249
241 return op - (u8 *) out_data; 250 return op - (u8 *) out_data;
242} 251}
252

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