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/cvs/liblzf/lzf_c.c
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Comparing liblzf/lzf_c.c (file contents):
Revision 1.15 by root, Fri Nov 2 12:39:20 2007 UTC vs.
Revision 1.20 by root, Tue Nov 13 08:38:49 2007 UTC

… …
21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- 21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
22 * 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
23 * OF THE POSSIBILITY OF SUCH DAMAGE. 23 * OF THE POSSIBILITY OF SUCH DAMAGE.
24 * 24 *
25 * 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
26 * 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,
27 * 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
28 * 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
29 * 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
30 * BSD license, indicate your decision by deleting the provisions above and 30 * version of this file under the BSD license, indicate your decision
31 * 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
32 * 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
33 * of this file under either the BSD or the GPL. 34 * either the BSD or the GPL.
34 */ 35 */
35 36
36#include "lzfP.h" 37#include "lzfP.h"
37 38
38#define HSIZE (1 << (HLOG)) 39#define HSIZE (1 << (HLOG))
… …
73# define lzf_movsb(dst, src, len) \ 74# define lzf_movsb(dst, src, len) \
74 asm ("rep movsb" \ 75 asm ("rep movsb" \
75 : "=D" (dst), "=S" (src), "=c" (len) \ 76 : "=D" (dst), "=S" (src), "=c" (len) \
76 : "0" (dst), "1" (src), "2" (len)); 77 : "0" (dst), "1" (src), "2" (len));
77#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)
78 90
79/* 91/*
80 * compressed format 92 * compressed format
81 * 93 *
82 * 000LLLLL <L+1> ; literal 94 * 000LLLLL <L+1> ; literal
… …
115# endif 127# endif
116#endif 128#endif
117 129
118 for (;;) 130 for (;;)
119 { 131 {
120 if (ip < in_end - 2) 132 if (expect_true (ip < in_end - 2))
121 { 133 {
122 hval = NEXT (hval, ip); 134 hval = NEXT (hval, ip);
123 hslot = htab + IDX (hval); 135 hslot = htab + IDX (hval);
124 ref = *hslot; *hslot = ip; 136 ref = *hslot; *hslot = ip;
125 137
… …
129#endif 141#endif
130 && (off = ip - ref - 1) < MAX_OFF 142 && (off = ip - ref - 1) < MAX_OFF
131 && ip + 4 < in_end 143 && ip + 4 < in_end
132 && ref > (u8 *)in_data 144 && ref > (u8 *)in_data
133#if STRICT_ALIGN 145#if STRICT_ALIGN
146 x x x
134 && ref[0] == ip[0] 147 && ref[0] == ip[0]
135 && ref[1] == ip[1] 148 && ref[1] == ip[1]
136 && ref[2] == ip[2] 149 && ref[2] == ip[2]
137#else 150#else
138 && *(u16 *)ref == *(u16 *)ip 151 && *(u16 *)ref == *(u16 *)ip
… …
143 /* match found at *ref++ */ 156 /* match found at *ref++ */
144 unsigned int len = 2; 157 unsigned int len = 2;
145 unsigned int maxlen = in_end - ip - len; 158 unsigned int maxlen = in_end - ip - len;
146 maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; 159 maxlen = maxlen > MAX_REF ? MAX_REF : maxlen;
147 160
148 if (op + lit + 1 + 3 >= out_end) 161 if (expect_false (op + lit + 1 + 3 >= out_end))
149 return 0; 162 return 0;
150 163
151 do 164 if (expect_false (lit))
152 len++;
153 while (len < maxlen && ref[len] == ip[len]);
154
155 if (lit)
156 { 165 {
157 *op++ = lit - 1; 166 *op++ = lit - 1;
158 lit = -lit; 167 lit = -lit;
159 do 168 do
160 *op++ = ip[lit]; 169 *op++ = ip[lit];
161 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;
162 } 200 }
163 201
164 len -= 2; 202 len -= 2;
165 ip++; 203 ip++;
166 204
… …
202 while (len--); 240 while (len--);
203#endif 241#endif
204 continue; 242 continue;
205 } 243 }
206 } 244 }
207 else if (ip == in_end) 245 else if (expect_false (ip == in_end))
208 break; 246 break;
209 247
210 /* one more literal byte we must copy */ 248 /* one more literal byte we must copy */
211 lit++; 249 lit++;
212 ip++; 250 ip++;
213 251
214 if (lit == MAX_LIT) 252 if (expect_false (lit == MAX_LIT))
215 { 253 {
216 if (op + 1 + MAX_LIT >= out_end) 254 if (op + 1 + MAX_LIT >= out_end)
217 return 0; 255 return 0;
218 256
219 *op++ = MAX_LIT - 1; 257 *op++ = MAX_LIT - 1;
220 258
221#ifdef lzf_movsb 259#ifdef lzf_movsb
222 ip -= lit; 260 ip -= MAX_LIT;
223 lzf_movsb (op, ip, lit); 261 lzf_movsb (op, ip, lit);
224#else 262#else
225 lit = -lit; 263 lit = -lit;
226 do 264 do
227 *op++ = ip[lit]; 265 *op++ = ip[lit];

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