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30static NOINLINE unsigned
31do_compress(const uint8_t* in, unsigned in_len,
32 uint8_t* out, unsigned* out_len,
33 void* wrkmem)
34{
35 register const uint8_t* ip;
36 uint8_t* op;
37 const uint8_t* const in_end = in + in_len;
38 const uint8_t* const ip_end = in + in_len - M2_MAX_LEN - 5;
39 const uint8_t* ii;
40 const void* *const dict = (const void**) wrkmem;
41
42 op = out;
43 ip = in;
44 ii = ip;
45
46 ip += 4;
47 for (;;) {
48 register const uint8_t* m_pos;
49 unsigned m_off;
50 unsigned m_len;
51 unsigned dindex;
52
53 D_INDEX1(dindex,ip);
54 GINDEX(m_pos,m_off,dict,dindex,in);
55 if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,M4_MAX_OFFSET))
56 goto literal;
57#if 1
58 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
59 goto try_match;
60 D_INDEX2(dindex,ip);
61#endif
62 GINDEX(m_pos,m_off,dict,dindex,in);
63 if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,M4_MAX_OFFSET))
64 goto literal;
65 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
66 goto try_match;
67 goto literal;
68
69 try_match:
70#if 1 && defined(LZO_UNALIGNED_OK_2)
71 if (* (const lzo_ushortp) m_pos != * (const lzo_ushortp) ip)
72#else
73 if (m_pos[0] != ip[0] || m_pos[1] != ip[1])
74#endif
75 {
76 } else {
77 if (m_pos[2] == ip[2]) {
78#if 0
79 if (m_off <= M2_MAX_OFFSET)
80 goto match;
81 if (lit <= 3)
82 goto match;
83 if (lit == 3) {
84 assert(op - 2 > out); op[-2] |= (uint8_t)(3);
85 *op++ = *ii++; *op++ = *ii++; *op++ = *ii++;
86 goto code_match;
87 }
88 if (m_pos[3] == ip[3])
89#endif
90 goto match;
91 }
92 else {
93
94#if 0
95
96#if 0
97 if (m_off <= M1_MAX_OFFSET && lit > 0 && lit <= 3)
98#else
99 if (m_off <= M1_MAX_OFFSET && lit == 3)
100#endif
101 {
102 register unsigned t;
103
104 t = lit;
105 assert(op - 2 > out); op[-2] |= (uint8_t)(t);
106 do *op++ = *ii++; while (--t > 0);
107 assert(ii == ip);
108 m_off -= 1;
109 *op++ = (uint8_t)(M1_MARKER | ((m_off & 3) << 2));
110 *op++ = (uint8_t)(m_off >> 2);
111 ip += 2;
112 goto match_done;
113 }
114#endif
115 }
116 }
117
118
119 literal:
120 UPDATE_I(dict, 0, dindex, ip, in);
121 ++ip;
122 if (ip >= ip_end)
123 break;
124 continue;
125
126
127match:
128 UPDATE_I(dict, 0, dindex, ip, in);
129
130 if (pd(ip, ii) > 0) {
131 register unsigned t = pd(ip, ii);
132
133 if (t <= 3) {
134 assert(op - 2 > out);
135 op[-2] |= (uint8_t)(t);
136 }
137 else if (t <= 18)
138 *op++ = (uint8_t)(t - 3);
139 else {
140 register unsigned tt = t - 18;
141
142 *op++ = 0;
143 while (tt > 255) {
144 tt -= 255;
145 *op++ = 0;
146 }
147 assert(tt > 0);
148 *op++ = (uint8_t)(tt);
149 }
150 do *op++ = *ii++; while (--t > 0);
151 }
152
153
154 assert(ii == ip);
155 ip += 3;
156 if (m_pos[3] != *ip++ || m_pos[4] != *ip++ || m_pos[5] != *ip++
157 || m_pos[6] != *ip++ || m_pos[7] != *ip++ || m_pos[8] != *ip++
158#ifdef LZO1Y
159 || m_pos[ 9] != *ip++ || m_pos[10] != *ip++ || m_pos[11] != *ip++
160 || m_pos[12] != *ip++ || m_pos[13] != *ip++ || m_pos[14] != *ip++
161#endif
162 ) {
163 --ip;
164 m_len = pd(ip, ii);
165 assert(m_len >= 3);
166 assert(m_len <= M2_MAX_LEN);
167
168 if (m_off <= M2_MAX_OFFSET) {
169 m_off -= 1;
170#if defined(LZO1X)
171 *op++ = (uint8_t)(((m_len - 1) << 5) | ((m_off & 7) << 2));
172 *op++ = (uint8_t)(m_off >> 3);
173#elif defined(LZO1Y)
174 *op++ = (uint8_t)(((m_len + 1) << 4) | ((m_off & 3) << 2));
175 *op++ = (uint8_t)(m_off >> 2);
176#endif
177 }
178 else if (m_off <= M3_MAX_OFFSET) {
179 m_off -= 1;
180 *op++ = (uint8_t)(M3_MARKER | (m_len - 2));
181 goto m3_m4_offset;
182 } else {
183#if defined(LZO1X)
184 m_off -= 0x4000;
185 assert(m_off > 0);
186 assert(m_off <= 0x7fff);
187 *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11) | (m_len - 2));
188 goto m3_m4_offset;
189#elif defined(LZO1Y)
190 goto m4_match;
191#endif
192 }
193 }
194 else {
195 {
196 const uint8_t* end = in_end;
197 const uint8_t* m = m_pos + M2_MAX_LEN + 1;
198 while (ip < end && *m == *ip)
199 m++, ip++;
200 m_len = pd(ip, ii);
201 }
202 assert(m_len > M2_MAX_LEN);
203
204 if (m_off <= M3_MAX_OFFSET) {
205 m_off -= 1;
206 if (m_len <= 33)
207 *op++ = (uint8_t)(M3_MARKER | (m_len - 2));
208 else {
209 m_len -= 33;
210 *op++ = M3_MARKER | 0;
211 goto m3_m4_len;
212 }
213 } else {
214#if defined(LZO1Y)
215 m4_match:
216#endif
217 m_off -= 0x4000;
218 assert(m_off > 0);
219 assert(m_off <= 0x7fff);
220 if (m_len <= M4_MAX_LEN)
221 *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11) | (m_len - 2));
222 else {
223 m_len -= M4_MAX_LEN;
224 *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11));
225 m3_m4_len:
226 while (m_len > 255) {
227 m_len -= 255;
228 *op++ = 0;
229 }
230 assert(m_len > 0);
231 *op++ = (uint8_t)(m_len);
232 }
233 }
234 m3_m4_offset:
235 *op++ = (uint8_t)((m_off & 63) << 2);
236 *op++ = (uint8_t)(m_off >> 6);
237 }
238#if 0
239 match_done:
240#endif
241 ii = ip;
242 if (ip >= ip_end)
243 break;
244 }
245
246 *out_len = pd(op, out);
247 return pd(in_end, ii);
248}
249
250
251
252
253int DO_COMPRESS(const uint8_t* in, unsigned in_len,
254 uint8_t* out, unsigned* out_len,
255 void* wrkmem)
256{
257 uint8_t* op = out;
258 unsigned t;
259
260 if (in_len <= M2_MAX_LEN + 5)
261 t = in_len;
262 else {
263 t = do_compress(in,in_len,op,out_len,wrkmem);
264 op += *out_len;
265 }
266
267 if (t > 0) {
268 const uint8_t* ii = in + in_len - t;
269
270 if (op == out && t <= 238)
271 *op++ = (uint8_t)(17 + t);
272 else if (t <= 3)
273 op[-2] |= (uint8_t)(t);
274 else if (t <= 18)
275 *op++ = (uint8_t)(t - 3);
276 else {
277 unsigned tt = t - 18;
278
279 *op++ = 0;
280 while (tt > 255) {
281 tt -= 255;
282 *op++ = 0;
283 }
284 assert(tt > 0);
285 *op++ = (uint8_t)(tt);
286 }
287 do *op++ = *ii++; while (--t > 0);
288 }
289
290 *op++ = M4_MARKER | 1;
291 *op++ = 0;
292 *op++ = 0;
293
294 *out_len = pd(op, out);
295 return 0;
296}
297
