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Comparing liblzf/lzf_c.c (file contents):
Revision 1.14 by root, Thu Jun 21 22:11:34 2007 UTC vs.
Revision 1.20 by root, Tue Nov 13 08:38:49 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-
… …
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- 21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 22 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 23 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 * 24 *
28 * Alternatively, the contents of this file may be used under the terms of 25 * Alternatively, the contents of this file may be used under the terms of
29 * the GNU General Public License version 2 (the "GPL"), in which case the 26 * the GNU General Public License ("GPL") version 2 or any later version,
30 * provisions of the GPL are applicable instead of the above. If you wish to 27 * in which case the provisions of the GPL are applicable instead of
31 * allow the use of your version of this file only under the terms of the 28 * the above. If you wish to allow the use of your version of this file
32 * GPL and not to allow others to use your version of this file under the 29 * only under the terms of the GPL and not to allow others to use your
33 * BSD license, indicate your decision by deleting the provisions above and 30 * version of this file under the BSD license, indicate your decision
34 * replace them with the notice and other provisions required by the GPL. If 31 * by deleting the provisions above and replace them with the notice
35 * you do not delete the provisions above, a recipient may use your version 32 * and other provisions required by the GPL. If you do not delete the
33 * provisions above, a recipient may use your version of this file under
36 * of this file under either the BSD or the GPL. 34 * either the BSD or the GPL.
37 */ 35 */
38 36
39#include "lzfP.h" 37#include "lzfP.h"
40 38
41#define HSIZE (1 << (HLOG)) 39#define HSIZE (1 << (HLOG))
… …
76# define lzf_movsb(dst, src, len) \ 74# define lzf_movsb(dst, src, len) \
77 asm ("rep movsb" \ 75 asm ("rep movsb" \
78 : "=D" (dst), "=S" (src), "=c" (len) \ 76 : "=D" (dst), "=S" (src), "=c" (len) \
79 : "0" (dst), "1" (src), "2" (len)); 77 : "0" (dst), "1" (src), "2" (len));
80#endif 78#endif
79
80#if __GNUC__ >= 3
81# define expect(expr,value) __builtin_expect ((expr),(value))
82# define inline inline
83#else
84# define expect(expr,value) (expr)
85# define inline static
86#endif
87
88#define expect_false(expr) expect ((expr) != 0, 0)
89#define expect_true(expr) expect ((expr) != 0, 1)
81 90
82/* 91/*
83 * compressed format 92 * compressed format
84 * 93 *
85 * 000LLLLL <L+1> ; literal 94 * 000LLLLL <L+1> ; literal
… …
118# endif 127# endif
119#endif 128#endif
120 129
121 for (;;) 130 for (;;)
122 { 131 {
123 if (ip < in_end - 2) 132 if (expect_true (ip < in_end - 2))
124 { 133 {
125 hval = NEXT (hval, ip); 134 hval = NEXT (hval, ip);
126 hslot = htab + IDX (hval); 135 hslot = htab + IDX (hval);
127 ref = *hslot; *hslot = ip; 136 ref = *hslot; *hslot = ip;
128 137
… …
132#endif 141#endif
133 && (off = ip - ref - 1) < MAX_OFF 142 && (off = ip - ref - 1) < MAX_OFF
134 && ip + 4 < in_end 143 && ip + 4 < in_end
135 && ref > (u8 *)in_data 144 && ref > (u8 *)in_data
136#if STRICT_ALIGN 145#if STRICT_ALIGN
146 x x x
137 && ref[0] == ip[0] 147 && ref[0] == ip[0]
138 && ref[1] == ip[1] 148 && ref[1] == ip[1]
139 && ref[2] == ip[2] 149 && ref[2] == ip[2]
140#else 150#else
141 && *(u16 *)ref == *(u16 *)ip 151 && *(u16 *)ref == *(u16 *)ip
… …
146 /* match found at *ref++ */ 156 /* match found at *ref++ */
147 unsigned int len = 2; 157 unsigned int len = 2;
148 unsigned int maxlen = in_end - ip - len; 158 unsigned int maxlen = in_end - ip - len;
149 maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; 159 maxlen = maxlen > MAX_REF ? MAX_REF : maxlen;
150 160
151 if (op + lit + 1 + 3 >= out_end) 161 if (expect_false (op + lit + 1 + 3 >= out_end))
152 return 0; 162 return 0;
153 163
154 do 164 if (expect_false (lit))
155 len++;
156 while (len < maxlen && ref[len] == ip[len]);
157
158 if (lit)
159 { 165 {
160 *op++ = lit - 1; 166 *op++ = lit - 1;
161 lit = -lit; 167 lit = -lit;
162 do 168 do
163 *op++ = ip[lit]; 169 *op++ = ip[lit];
164 while (++lit); 170 while (expect_false (++lit));
171 }
172
173 for (;;)
174 {
175 if (expect_true (maxlen > 16))
176 {
177 len++; if (ref [len] != ip [len]) break;
178 len++; if (ref [len] != ip [len]) break;
179 len++; if (ref [len] != ip [len]) break;
180 len++; if (ref [len] != ip [len]) break;
181 len++; if (ref [len] != ip [len]) break;
182 len++; if (ref [len] != ip [len]) break;
183 len++; if (ref [len] != ip [len]) break;
184 len++; if (ref [len] != ip [len]) break;
185 len++; if (ref [len] != ip [len]) break;
186 len++; if (ref [len] != ip [len]) break;
187 len++; if (ref [len] != ip [len]) break;
188 len++; if (ref [len] != ip [len]) break;
189 len++; if (ref [len] != ip [len]) break;
190 len++; if (ref [len] != ip [len]) break;
191 len++; if (ref [len] != ip [len]) break;
192 len++; if (ref [len] != ip [len]) break;
193 }
194
195 do
196 len++;
197 while (len < maxlen && ref[len] == ip[len]);
198
199 break;
165 } 200 }
166 201
167 len -= 2; 202 len -= 2;
168 ip++; 203 ip++;
169 204
… …
205 while (len--); 240 while (len--);
206#endif 241#endif
207 continue; 242 continue;
208 } 243 }
209 } 244 }
210 else if (ip == in_end) 245 else if (expect_false (ip == in_end))
211 break; 246 break;
212 247
213 /* one more literal byte we must copy */ 248 /* one more literal byte we must copy */
214 lit++; 249 lit++;
215 ip++; 250 ip++;
216 251
217 if (lit == MAX_LIT) 252 if (expect_false (lit == MAX_LIT))
218 { 253 {
219 if (op + 1 + MAX_LIT >= out_end) 254 if (op + 1 + MAX_LIT >= out_end)
220 return 0; 255 return 0;
221 256
222 *op++ = MAX_LIT - 1; 257 *op++ = MAX_LIT - 1;
223 258
224#ifdef lzf_movsb 259#ifdef lzf_movsb
225 ip -= lit; 260 ip -= MAX_LIT;
226 lzf_movsb (op, ip, lit); 261 lzf_movsb (op, ip, lit);
227#else 262#else
228 lit = -lit; 263 lit = -lit;
229 do 264 do
230 *op++ = ip[lit]; 265 *op++ = ip[lit];

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