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Commit | Line | Data |
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1da177e4 LT |
1 | /* Generate assembler source containing symbol information |
2 | * | |
3 | * Copyright 2002 by Kai Germaschewski | |
4 | * | |
5 | * This software may be used and distributed according to the terms | |
6 | * of the GNU General Public License, incorporated herein by reference. | |
7 | * | |
8 | * Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S | |
9 | * | |
1da177e4 LT |
10 | * Table compression uses all the unused char codes on the symbols and |
11 | * maps these to the most used substrings (tokens). For instance, it might | |
12 | * map char code 0xF7 to represent "write_" and then in every symbol where | |
13 | * "write_" appears it can be replaced by 0xF7, saving 5 bytes. | |
14 | * The used codes themselves are also placed in the table so that the | |
15 | * decompresion can work without "special cases". | |
16 | * Applied to kernel symbols, this usually produces a compression ratio | |
17 | * of about 50%. | |
18 | * | |
19 | */ | |
20 | ||
21 | #include <stdio.h> | |
22 | #include <stdlib.h> | |
23 | #include <string.h> | |
24 | #include <ctype.h> | |
2213e9a6 | 25 | #include <limits.h> |
1da177e4 | 26 | |
17b1f0de MF |
27 | #ifndef ARRAY_SIZE |
28 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) | |
29 | #endif | |
30 | ||
9281acea | 31 | #define KSYM_NAME_LEN 128 |
1da177e4 | 32 | |
1da177e4 LT |
33 | struct sym_entry { |
34 | unsigned long long addr; | |
b3dbb4ec | 35 | unsigned int len; |
f2df3f65 | 36 | unsigned int start_pos; |
1da177e4 | 37 | unsigned char *sym; |
8c996940 | 38 | unsigned int percpu_absolute; |
1da177e4 LT |
39 | }; |
40 | ||
78eb7159 KC |
41 | struct addr_range { |
42 | const char *start_sym, *end_sym; | |
17b1f0de MF |
43 | unsigned long long start, end; |
44 | }; | |
45 | ||
46 | static unsigned long long _text; | |
2213e9a6 | 47 | static unsigned long long relative_base; |
78eb7159 | 48 | static struct addr_range text_ranges[] = { |
17b1f0de MF |
49 | { "_stext", "_etext" }, |
50 | { "_sinittext", "_einittext" }, | |
51 | { "_stext_l1", "_etext_l1" }, /* Blackfin on-chip L1 inst SRAM */ | |
52 | { "_stext_l2", "_etext_l2" }, /* Blackfin on-chip L2 SRAM */ | |
53 | }; | |
54 | #define text_range_text (&text_ranges[0]) | |
55 | #define text_range_inittext (&text_ranges[1]) | |
56 | ||
c6bda7c9 RR |
57 | static struct addr_range percpu_range = { |
58 | "__per_cpu_start", "__per_cpu_end", -1ULL, 0 | |
59 | }; | |
60 | ||
1da177e4 | 61 | static struct sym_entry *table; |
b3dbb4ec | 62 | static unsigned int table_size, table_cnt; |
1da177e4 | 63 | static int all_symbols = 0; |
c6bda7c9 | 64 | static int absolute_percpu = 0; |
41f11a4f | 65 | static char symbol_prefix_char = '\0'; |
2213e9a6 | 66 | static int base_relative = 0; |
1da177e4 | 67 | |
b3dbb4ec | 68 | int token_profit[0x10000]; |
1da177e4 LT |
69 | |
70 | /* the table that holds the result of the compression */ | |
b3dbb4ec | 71 | unsigned char best_table[256][2]; |
1da177e4 LT |
72 | unsigned char best_table_len[256]; |
73 | ||
74 | ||
b3dbb4ec | 75 | static void usage(void) |
1da177e4 | 76 | { |
f6537f2f ML |
77 | fprintf(stderr, "Usage: kallsyms [--all-symbols] " |
78 | "[--symbol-prefix=<prefix char>] " | |
2213e9a6 | 79 | "[--base-relative] < in.map > out.S\n"); |
1da177e4 LT |
80 | exit(1); |
81 | } | |
82 | ||
83 | /* | |
84 | * This ignores the intensely annoying "mapping symbols" found | |
85 | * in ARM ELF files: $a, $t and $d. | |
86 | */ | |
b3dbb4ec | 87 | static inline int is_arm_mapping_symbol(const char *str) |
1da177e4 | 88 | { |
6c34f1f5 | 89 | return str[0] == '$' && strchr("axtd", str[1]) |
1da177e4 LT |
90 | && (str[2] == '\0' || str[2] == '.'); |
91 | } | |
92 | ||
78eb7159 KC |
93 | static int check_symbol_range(const char *sym, unsigned long long addr, |
94 | struct addr_range *ranges, int entries) | |
17b1f0de MF |
95 | { |
96 | size_t i; | |
78eb7159 | 97 | struct addr_range *ar; |
17b1f0de | 98 | |
78eb7159 KC |
99 | for (i = 0; i < entries; ++i) { |
100 | ar = &ranges[i]; | |
17b1f0de | 101 | |
78eb7159 KC |
102 | if (strcmp(sym, ar->start_sym) == 0) { |
103 | ar->start = addr; | |
17b1f0de | 104 | return 0; |
78eb7159 KC |
105 | } else if (strcmp(sym, ar->end_sym) == 0) { |
106 | ar->end = addr; | |
17b1f0de MF |
107 | return 0; |
108 | } | |
109 | } | |
110 | ||
111 | return 1; | |
112 | } | |
113 | ||
b3dbb4ec | 114 | static int read_symbol(FILE *in, struct sym_entry *s) |
1da177e4 LT |
115 | { |
116 | char str[500]; | |
b3dbb4ec | 117 | char *sym, stype; |
1da177e4 LT |
118 | int rc; |
119 | ||
b3dbb4ec | 120 | rc = fscanf(in, "%llx %c %499s\n", &s->addr, &stype, str); |
1da177e4 | 121 | if (rc != 3) { |
ef894870 JS |
122 | if (rc != EOF && fgets(str, 500, in) == NULL) |
123 | fprintf(stderr, "Read error or end of file.\n"); | |
1da177e4 LT |
124 | return -1; |
125 | } | |
f3462aa9 | 126 | if (strlen(str) > KSYM_NAME_LEN) { |
6f62259b | 127 | fprintf(stderr, "Symbol %s too long for kallsyms (%zu vs %d).\n" |
bb66fc67 | 128 | "Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n", |
f3462aa9 AK |
129 | str, strlen(str), KSYM_NAME_LEN); |
130 | return -1; | |
131 | } | |
1da177e4 | 132 | |
41f11a4f YS |
133 | sym = str; |
134 | /* skip prefix char */ | |
135 | if (symbol_prefix_char && str[0] == symbol_prefix_char) | |
136 | sym++; | |
137 | ||
1da177e4 | 138 | /* Ignore most absolute/undefined (?) symbols. */ |
fd593d12 EB |
139 | if (strcmp(sym, "_text") == 0) |
140 | _text = s->addr; | |
78eb7159 KC |
141 | else if (check_symbol_range(sym, s->addr, text_ranges, |
142 | ARRAY_SIZE(text_ranges)) == 0) | |
17b1f0de | 143 | /* nothing to do */; |
b3dbb4ec | 144 | else if (toupper(stype) == 'A') |
1da177e4 LT |
145 | { |
146 | /* Keep these useful absolute symbols */ | |
41f11a4f YS |
147 | if (strcmp(sym, "__kernel_syscall_via_break") && |
148 | strcmp(sym, "__kernel_syscall_via_epc") && | |
149 | strcmp(sym, "__kernel_sigtramp") && | |
150 | strcmp(sym, "__gp")) | |
1da177e4 LT |
151 | return -1; |
152 | ||
153 | } | |
b3dbb4ec | 154 | else if (toupper(stype) == 'U' || |
41f11a4f | 155 | is_arm_mapping_symbol(sym)) |
1da177e4 | 156 | return -1; |
6f00df24 RB |
157 | /* exclude also MIPS ELF local symbols ($L123 instead of .L123) */ |
158 | else if (str[0] == '$') | |
159 | return -1; | |
aab34ac8 SR |
160 | /* exclude debugging symbols */ |
161 | else if (stype == 'N') | |
162 | return -1; | |
1da177e4 LT |
163 | |
164 | /* include the type field in the symbol name, so that it gets | |
165 | * compressed together */ | |
166 | s->len = strlen(str) + 1; | |
b3dbb4ec | 167 | s->sym = malloc(s->len + 1); |
f1a136e0 JJ |
168 | if (!s->sym) { |
169 | fprintf(stderr, "kallsyms failure: " | |
170 | "unable to allocate required amount of memory\n"); | |
171 | exit(EXIT_FAILURE); | |
172 | } | |
b3dbb4ec PM |
173 | strcpy((char *)s->sym + 1, str); |
174 | s->sym[0] = stype; | |
1da177e4 | 175 | |
8c996940 AB |
176 | s->percpu_absolute = 0; |
177 | ||
c6bda7c9 RR |
178 | /* Record if we've found __per_cpu_start/end. */ |
179 | check_symbol_range(sym, s->addr, &percpu_range, 1); | |
180 | ||
1da177e4 LT |
181 | return 0; |
182 | } | |
183 | ||
78eb7159 KC |
184 | static int symbol_in_range(struct sym_entry *s, struct addr_range *ranges, |
185 | int entries) | |
17b1f0de MF |
186 | { |
187 | size_t i; | |
78eb7159 | 188 | struct addr_range *ar; |
17b1f0de | 189 | |
78eb7159 KC |
190 | for (i = 0; i < entries; ++i) { |
191 | ar = &ranges[i]; | |
17b1f0de | 192 | |
78eb7159 | 193 | if (s->addr >= ar->start && s->addr <= ar->end) |
ac6ca5c8 | 194 | return 1; |
17b1f0de MF |
195 | } |
196 | ||
ac6ca5c8 | 197 | return 0; |
17b1f0de MF |
198 | } |
199 | ||
b3dbb4ec | 200 | static int symbol_valid(struct sym_entry *s) |
1da177e4 LT |
201 | { |
202 | /* Symbols which vary between passes. Passes 1 and 2 must have | |
2ea03891 SR |
203 | * identical symbol lists. The kallsyms_* symbols below are only added |
204 | * after pass 1, they would be included in pass 2 when --all-symbols is | |
205 | * specified so exclude them to get a stable symbol list. | |
1da177e4 LT |
206 | */ |
207 | static char *special_symbols[] = { | |
2ea03891 | 208 | "kallsyms_addresses", |
2213e9a6 AB |
209 | "kallsyms_offsets", |
210 | "kallsyms_relative_base", | |
2ea03891 SR |
211 | "kallsyms_num_syms", |
212 | "kallsyms_names", | |
213 | "kallsyms_markers", | |
214 | "kallsyms_token_table", | |
215 | "kallsyms_token_index", | |
216 | ||
1da177e4 LT |
217 | /* Exclude linker generated symbols which vary between passes */ |
218 | "_SDA_BASE_", /* ppc */ | |
219 | "_SDA2_BASE_", /* ppc */ | |
220 | NULL }; | |
bd8b22d2 AB |
221 | |
222 | static char *special_suffixes[] = { | |
bd8b22d2 | 223 | "_veneer", /* arm */ |
b9b74be1 AB |
224 | "_from_arm", /* arm */ |
225 | "_from_thumb", /* arm */ | |
bd8b22d2 AB |
226 | NULL }; |
227 | ||
1da177e4 | 228 | int i; |
bd8b22d2 AB |
229 | char *sym_name = (char *)s->sym + 1; |
230 | ||
41f11a4f | 231 | /* skip prefix char */ |
bd8b22d2 AB |
232 | if (symbol_prefix_char && *sym_name == symbol_prefix_char) |
233 | sym_name++; | |
234 | ||
1da177e4 LT |
235 | |
236 | /* if --all-symbols is not specified, then symbols outside the text | |
237 | * and inittext sections are discarded */ | |
238 | if (!all_symbols) { | |
78eb7159 KC |
239 | if (symbol_in_range(s, text_ranges, |
240 | ARRAY_SIZE(text_ranges)) == 0) | |
1da177e4 LT |
241 | return 0; |
242 | /* Corner case. Discard any symbols with the same value as | |
a3b81113 RG |
243 | * _etext _einittext; they can move between pass 1 and 2 when |
244 | * the kallsyms data are added. If these symbols move then | |
245 | * they may get dropped in pass 2, which breaks the kallsyms | |
246 | * rules. | |
1da177e4 | 247 | */ |
17b1f0de | 248 | if ((s->addr == text_range_text->end && |
bd8b22d2 | 249 | strcmp(sym_name, |
78eb7159 | 250 | text_range_text->end_sym)) || |
17b1f0de | 251 | (s->addr == text_range_inittext->end && |
bd8b22d2 | 252 | strcmp(sym_name, |
78eb7159 | 253 | text_range_inittext->end_sym))) |
1da177e4 LT |
254 | return 0; |
255 | } | |
256 | ||
257 | /* Exclude symbols which vary between passes. */ | |
1da177e4 | 258 | for (i = 0; special_symbols[i]; i++) |
bd8b22d2 | 259 | if (strcmp(sym_name, special_symbols[i]) == 0) |
1da177e4 LT |
260 | return 0; |
261 | ||
bd8b22d2 AB |
262 | for (i = 0; special_suffixes[i]; i++) { |
263 | int l = strlen(sym_name) - strlen(special_suffixes[i]); | |
264 | ||
265 | if (l >= 0 && strcmp(sym_name + l, special_suffixes[i]) == 0) | |
266 | return 0; | |
267 | } | |
268 | ||
1da177e4 LT |
269 | return 1; |
270 | } | |
271 | ||
b3dbb4ec | 272 | static void read_map(FILE *in) |
1da177e4 LT |
273 | { |
274 | while (!feof(in)) { | |
b3dbb4ec PM |
275 | if (table_cnt >= table_size) { |
276 | table_size += 10000; | |
277 | table = realloc(table, sizeof(*table) * table_size); | |
1da177e4 LT |
278 | if (!table) { |
279 | fprintf(stderr, "out of memory\n"); | |
280 | exit (1); | |
281 | } | |
282 | } | |
f2df3f65 PM |
283 | if (read_symbol(in, &table[table_cnt]) == 0) { |
284 | table[table_cnt].start_pos = table_cnt; | |
b3dbb4ec | 285 | table_cnt++; |
f2df3f65 | 286 | } |
1da177e4 LT |
287 | } |
288 | } | |
289 | ||
290 | static void output_label(char *label) | |
291 | { | |
41f11a4f YS |
292 | if (symbol_prefix_char) |
293 | printf(".globl %c%s\n", symbol_prefix_char, label); | |
294 | else | |
295 | printf(".globl %s\n", label); | |
1da177e4 | 296 | printf("\tALGN\n"); |
41f11a4f YS |
297 | if (symbol_prefix_char) |
298 | printf("%c%s:\n", symbol_prefix_char, label); | |
299 | else | |
300 | printf("%s:\n", label); | |
1da177e4 LT |
301 | } |
302 | ||
303 | /* uncompress a compressed symbol. When this function is called, the best table | |
304 | * might still be compressed itself, so the function needs to be recursive */ | |
305 | static int expand_symbol(unsigned char *data, int len, char *result) | |
306 | { | |
307 | int c, rlen, total=0; | |
308 | ||
309 | while (len) { | |
310 | c = *data; | |
311 | /* if the table holds a single char that is the same as the one | |
312 | * we are looking for, then end the search */ | |
313 | if (best_table[c][0]==c && best_table_len[c]==1) { | |
314 | *result++ = c; | |
315 | total++; | |
316 | } else { | |
317 | /* if not, recurse and expand */ | |
318 | rlen = expand_symbol(best_table[c], best_table_len[c], result); | |
319 | total += rlen; | |
320 | result += rlen; | |
321 | } | |
322 | data++; | |
323 | len--; | |
324 | } | |
325 | *result=0; | |
326 | ||
327 | return total; | |
328 | } | |
329 | ||
78eb7159 KC |
330 | static int symbol_absolute(struct sym_entry *s) |
331 | { | |
8c996940 | 332 | return s->percpu_absolute; |
78eb7159 KC |
333 | } |
334 | ||
b3dbb4ec | 335 | static void write_src(void) |
1da177e4 | 336 | { |
b3dbb4ec | 337 | unsigned int i, k, off; |
1da177e4 LT |
338 | unsigned int best_idx[256]; |
339 | unsigned int *markers; | |
9281acea | 340 | char buf[KSYM_NAME_LEN]; |
1da177e4 LT |
341 | |
342 | printf("#include <asm/types.h>\n"); | |
343 | printf("#if BITS_PER_LONG == 64\n"); | |
344 | printf("#define PTR .quad\n"); | |
345 | printf("#define ALGN .align 8\n"); | |
346 | printf("#else\n"); | |
347 | printf("#define PTR .long\n"); | |
348 | printf("#define ALGN .align 4\n"); | |
349 | printf("#endif\n"); | |
350 | ||
aad09470 | 351 | printf("\t.section .rodata, \"a\"\n"); |
1da177e4 | 352 | |
2213e9a6 AB |
353 | /* Provide proper symbols relocatability by their relativeness |
354 | * to a fixed anchor point in the runtime image, either '_text' | |
355 | * for absolute address tables, in which case the linker will | |
356 | * emit the final addresses at build time. Otherwise, use the | |
357 | * offset relative to the lowest value encountered of all relative | |
358 | * symbols, and emit non-relocatable fixed offsets that will be fixed | |
359 | * up at runtime. | |
360 | * | |
361 | * The symbol names cannot be used to construct normal symbol | |
362 | * references as the list of symbols contains symbols that are | |
363 | * declared static and are private to their .o files. This prevents | |
364 | * .tmp_kallsyms.o or any other object from referencing them. | |
fd593d12 | 365 | */ |
2213e9a6 AB |
366 | if (!base_relative) |
367 | output_label("kallsyms_addresses"); | |
368 | else | |
369 | output_label("kallsyms_offsets"); | |
370 | ||
b3dbb4ec | 371 | for (i = 0; i < table_cnt; i++) { |
2213e9a6 AB |
372 | if (base_relative) { |
373 | long long offset; | |
374 | int overflow; | |
375 | ||
376 | if (!absolute_percpu) { | |
377 | offset = table[i].addr - relative_base; | |
378 | overflow = (offset < 0 || offset > UINT_MAX); | |
379 | } else if (symbol_absolute(&table[i])) { | |
380 | offset = table[i].addr; | |
381 | overflow = (offset < 0 || offset > INT_MAX); | |
382 | } else { | |
383 | offset = relative_base - table[i].addr - 1; | |
384 | overflow = (offset < INT_MIN || offset >= 0); | |
385 | } | |
386 | if (overflow) { | |
387 | fprintf(stderr, "kallsyms failure: " | |
388 | "%s symbol value %#llx out of range in relative mode\n", | |
389 | symbol_absolute(&table[i]) ? "absolute" : "relative", | |
390 | table[i].addr); | |
391 | exit(EXIT_FAILURE); | |
392 | } | |
393 | printf("\t.long\t%#x\n", (int)offset); | |
394 | } else if (!symbol_absolute(&table[i])) { | |
2c22d8ba VG |
395 | if (_text <= table[i].addr) |
396 | printf("\tPTR\t_text + %#llx\n", | |
397 | table[i].addr - _text); | |
398 | else | |
2930ffc7 AM |
399 | printf("\tPTR\t_text - %#llx\n", |
400 | _text - table[i].addr); | |
fd593d12 EB |
401 | } else { |
402 | printf("\tPTR\t%#llx\n", table[i].addr); | |
403 | } | |
1da177e4 LT |
404 | } |
405 | printf("\n"); | |
406 | ||
2213e9a6 AB |
407 | if (base_relative) { |
408 | output_label("kallsyms_relative_base"); | |
409 | printf("\tPTR\t_text - %#llx\n", _text - relative_base); | |
410 | printf("\n"); | |
411 | } | |
412 | ||
1da177e4 | 413 | output_label("kallsyms_num_syms"); |
b3dbb4ec | 414 | printf("\tPTR\t%d\n", table_cnt); |
1da177e4 LT |
415 | printf("\n"); |
416 | ||
417 | /* table of offset markers, that give the offset in the compressed stream | |
418 | * every 256 symbols */ | |
f1a136e0 JJ |
419 | markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256)); |
420 | if (!markers) { | |
421 | fprintf(stderr, "kallsyms failure: " | |
422 | "unable to allocate required memory\n"); | |
423 | exit(EXIT_FAILURE); | |
424 | } | |
1da177e4 LT |
425 | |
426 | output_label("kallsyms_names"); | |
1da177e4 | 427 | off = 0; |
b3dbb4ec PM |
428 | for (i = 0; i < table_cnt; i++) { |
429 | if ((i & 0xFF) == 0) | |
430 | markers[i >> 8] = off; | |
1da177e4 LT |
431 | |
432 | printf("\t.byte 0x%02x", table[i].len); | |
433 | for (k = 0; k < table[i].len; k++) | |
434 | printf(", 0x%02x", table[i].sym[k]); | |
435 | printf("\n"); | |
436 | ||
437 | off += table[i].len + 1; | |
1da177e4 LT |
438 | } |
439 | printf("\n"); | |
440 | ||
441 | output_label("kallsyms_markers"); | |
b3dbb4ec | 442 | for (i = 0; i < ((table_cnt + 255) >> 8); i++) |
1da177e4 LT |
443 | printf("\tPTR\t%d\n", markers[i]); |
444 | printf("\n"); | |
445 | ||
446 | free(markers); | |
447 | ||
448 | output_label("kallsyms_token_table"); | |
449 | off = 0; | |
450 | for (i = 0; i < 256; i++) { | |
451 | best_idx[i] = off; | |
b3dbb4ec | 452 | expand_symbol(best_table[i], best_table_len[i], buf); |
1da177e4 LT |
453 | printf("\t.asciz\t\"%s\"\n", buf); |
454 | off += strlen(buf) + 1; | |
455 | } | |
456 | printf("\n"); | |
457 | ||
458 | output_label("kallsyms_token_index"); | |
459 | for (i = 0; i < 256; i++) | |
460 | printf("\t.short\t%d\n", best_idx[i]); | |
461 | printf("\n"); | |
462 | } | |
463 | ||
464 | ||
465 | /* table lookup compression functions */ | |
466 | ||
1da177e4 LT |
467 | /* count all the possible tokens in a symbol */ |
468 | static void learn_symbol(unsigned char *symbol, int len) | |
469 | { | |
470 | int i; | |
471 | ||
472 | for (i = 0; i < len - 1; i++) | |
b3dbb4ec | 473 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++; |
1da177e4 LT |
474 | } |
475 | ||
476 | /* decrease the count for all the possible tokens in a symbol */ | |
477 | static void forget_symbol(unsigned char *symbol, int len) | |
478 | { | |
479 | int i; | |
480 | ||
481 | for (i = 0; i < len - 1; i++) | |
b3dbb4ec | 482 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--; |
1da177e4 LT |
483 | } |
484 | ||
b3dbb4ec | 485 | /* remove all the invalid symbols from the table and do the initial token count */ |
1da177e4 LT |
486 | static void build_initial_tok_table(void) |
487 | { | |
b3dbb4ec | 488 | unsigned int i, pos; |
1da177e4 | 489 | |
b3dbb4ec PM |
490 | pos = 0; |
491 | for (i = 0; i < table_cnt; i++) { | |
1da177e4 | 492 | if ( symbol_valid(&table[i]) ) { |
b3dbb4ec PM |
493 | if (pos != i) |
494 | table[pos] = table[i]; | |
495 | learn_symbol(table[pos].sym, table[pos].len); | |
496 | pos++; | |
1da177e4 | 497 | } |
1da177e4 | 498 | } |
b3dbb4ec | 499 | table_cnt = pos; |
1da177e4 LT |
500 | } |
501 | ||
7c5d249a PM |
502 | static void *find_token(unsigned char *str, int len, unsigned char *token) |
503 | { | |
504 | int i; | |
505 | ||
506 | for (i = 0; i < len - 1; i++) { | |
507 | if (str[i] == token[0] && str[i+1] == token[1]) | |
508 | return &str[i]; | |
509 | } | |
510 | return NULL; | |
511 | } | |
512 | ||
1da177e4 LT |
513 | /* replace a given token in all the valid symbols. Use the sampled symbols |
514 | * to update the counts */ | |
b3dbb4ec | 515 | static void compress_symbols(unsigned char *str, int idx) |
1da177e4 | 516 | { |
b3dbb4ec PM |
517 | unsigned int i, len, size; |
518 | unsigned char *p1, *p2; | |
1da177e4 | 519 | |
b3dbb4ec | 520 | for (i = 0; i < table_cnt; i++) { |
1da177e4 LT |
521 | |
522 | len = table[i].len; | |
b3dbb4ec PM |
523 | p1 = table[i].sym; |
524 | ||
525 | /* find the token on the symbol */ | |
7c5d249a | 526 | p2 = find_token(p1, len, str); |
b3dbb4ec PM |
527 | if (!p2) continue; |
528 | ||
529 | /* decrease the counts for this symbol's tokens */ | |
530 | forget_symbol(table[i].sym, len); | |
531 | ||
532 | size = len; | |
1da177e4 LT |
533 | |
534 | do { | |
b3dbb4ec PM |
535 | *p2 = idx; |
536 | p2++; | |
537 | size -= (p2 - p1); | |
538 | memmove(p2, p2 + 1, size); | |
539 | p1 = p2; | |
540 | len--; | |
541 | ||
542 | if (size < 2) break; | |
543 | ||
1da177e4 | 544 | /* find the token on the symbol */ |
7c5d249a | 545 | p2 = find_token(p1, size, str); |
1da177e4 | 546 | |
b3dbb4ec | 547 | } while (p2); |
1da177e4 | 548 | |
b3dbb4ec | 549 | table[i].len = len; |
1da177e4 | 550 | |
b3dbb4ec PM |
551 | /* increase the counts for this symbol's new tokens */ |
552 | learn_symbol(table[i].sym, len); | |
1da177e4 LT |
553 | } |
554 | } | |
555 | ||
556 | /* search the token with the maximum profit */ | |
b3dbb4ec | 557 | static int find_best_token(void) |
1da177e4 | 558 | { |
b3dbb4ec | 559 | int i, best, bestprofit; |
1da177e4 LT |
560 | |
561 | bestprofit=-10000; | |
b3dbb4ec | 562 | best = 0; |
1da177e4 | 563 | |
b3dbb4ec PM |
564 | for (i = 0; i < 0x10000; i++) { |
565 | if (token_profit[i] > bestprofit) { | |
566 | best = i; | |
567 | bestprofit = token_profit[i]; | |
1da177e4 | 568 | } |
1da177e4 | 569 | } |
1da177e4 LT |
570 | return best; |
571 | } | |
572 | ||
573 | /* this is the core of the algorithm: calculate the "best" table */ | |
574 | static void optimize_result(void) | |
575 | { | |
b3dbb4ec | 576 | int i, best; |
1da177e4 LT |
577 | |
578 | /* using the '\0' symbol last allows compress_symbols to use standard | |
579 | * fast string functions */ | |
580 | for (i = 255; i >= 0; i--) { | |
581 | ||
582 | /* if this table slot is empty (it is not used by an actual | |
583 | * original char code */ | |
584 | if (!best_table_len[i]) { | |
585 | ||
586 | /* find the token with the breates profit value */ | |
587 | best = find_best_token(); | |
e0a04b11 XW |
588 | if (token_profit[best] == 0) |
589 | break; | |
1da177e4 LT |
590 | |
591 | /* place it in the "best" table */ | |
b3dbb4ec PM |
592 | best_table_len[i] = 2; |
593 | best_table[i][0] = best & 0xFF; | |
594 | best_table[i][1] = (best >> 8) & 0xFF; | |
1da177e4 LT |
595 | |
596 | /* replace this token in all the valid symbols */ | |
b3dbb4ec | 597 | compress_symbols(best_table[i], i); |
1da177e4 LT |
598 | } |
599 | } | |
600 | } | |
601 | ||
602 | /* start by placing the symbols that are actually used on the table */ | |
603 | static void insert_real_symbols_in_table(void) | |
604 | { | |
b3dbb4ec | 605 | unsigned int i, j, c; |
1da177e4 LT |
606 | |
607 | memset(best_table, 0, sizeof(best_table)); | |
608 | memset(best_table_len, 0, sizeof(best_table_len)); | |
609 | ||
b3dbb4ec PM |
610 | for (i = 0; i < table_cnt; i++) { |
611 | for (j = 0; j < table[i].len; j++) { | |
612 | c = table[i].sym[j]; | |
613 | best_table[c][0]=c; | |
614 | best_table_len[c]=1; | |
1da177e4 LT |
615 | } |
616 | } | |
617 | } | |
618 | ||
619 | static void optimize_token_table(void) | |
620 | { | |
1da177e4 LT |
621 | build_initial_tok_table(); |
622 | ||
623 | insert_real_symbols_in_table(); | |
624 | ||
41f11a4f | 625 | /* When valid symbol is not registered, exit to error */ |
b3dbb4ec | 626 | if (!table_cnt) { |
41f11a4f YS |
627 | fprintf(stderr, "No valid symbol.\n"); |
628 | exit(1); | |
629 | } | |
630 | ||
1da177e4 LT |
631 | optimize_result(); |
632 | } | |
633 | ||
b478b782 LJ |
634 | /* guess for "linker script provide" symbol */ |
635 | static int may_be_linker_script_provide_symbol(const struct sym_entry *se) | |
636 | { | |
637 | const char *symbol = (char *)se->sym + 1; | |
638 | int len = se->len - 1; | |
639 | ||
640 | if (len < 8) | |
641 | return 0; | |
642 | ||
643 | if (symbol[0] != '_' || symbol[1] != '_') | |
644 | return 0; | |
645 | ||
646 | /* __start_XXXXX */ | |
647 | if (!memcmp(symbol + 2, "start_", 6)) | |
648 | return 1; | |
649 | ||
650 | /* __stop_XXXXX */ | |
651 | if (!memcmp(symbol + 2, "stop_", 5)) | |
652 | return 1; | |
653 | ||
654 | /* __end_XXXXX */ | |
655 | if (!memcmp(symbol + 2, "end_", 4)) | |
656 | return 1; | |
657 | ||
658 | /* __XXXXX_start */ | |
659 | if (!memcmp(symbol + len - 6, "_start", 6)) | |
660 | return 1; | |
661 | ||
662 | /* __XXXXX_end */ | |
663 | if (!memcmp(symbol + len - 4, "_end", 4)) | |
664 | return 1; | |
665 | ||
666 | return 0; | |
667 | } | |
668 | ||
669 | static int prefix_underscores_count(const char *str) | |
670 | { | |
671 | const char *tail = str; | |
672 | ||
a9ece53c | 673 | while (*tail == '_') |
b478b782 LJ |
674 | tail++; |
675 | ||
676 | return tail - str; | |
677 | } | |
678 | ||
f2df3f65 PM |
679 | static int compare_symbols(const void *a, const void *b) |
680 | { | |
681 | const struct sym_entry *sa; | |
682 | const struct sym_entry *sb; | |
683 | int wa, wb; | |
684 | ||
685 | sa = a; | |
686 | sb = b; | |
687 | ||
688 | /* sort by address first */ | |
689 | if (sa->addr > sb->addr) | |
690 | return 1; | |
691 | if (sa->addr < sb->addr) | |
692 | return -1; | |
693 | ||
694 | /* sort by "weakness" type */ | |
695 | wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W'); | |
696 | wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W'); | |
697 | if (wa != wb) | |
698 | return wa - wb; | |
699 | ||
b478b782 LJ |
700 | /* sort by "linker script provide" type */ |
701 | wa = may_be_linker_script_provide_symbol(sa); | |
702 | wb = may_be_linker_script_provide_symbol(sb); | |
703 | if (wa != wb) | |
704 | return wa - wb; | |
705 | ||
706 | /* sort by the number of prefix underscores */ | |
707 | wa = prefix_underscores_count((const char *)sa->sym + 1); | |
708 | wb = prefix_underscores_count((const char *)sb->sym + 1); | |
709 | if (wa != wb) | |
710 | return wa - wb; | |
711 | ||
f2df3f65 PM |
712 | /* sort by initial order, so that other symbols are left undisturbed */ |
713 | return sa->start_pos - sb->start_pos; | |
714 | } | |
715 | ||
716 | static void sort_symbols(void) | |
717 | { | |
718 | qsort(table, table_cnt, sizeof(struct sym_entry), compare_symbols); | |
719 | } | |
1da177e4 | 720 | |
c6bda7c9 RR |
721 | static void make_percpus_absolute(void) |
722 | { | |
723 | unsigned int i; | |
724 | ||
725 | for (i = 0; i < table_cnt; i++) | |
8c996940 AB |
726 | if (symbol_in_range(&table[i], &percpu_range, 1)) { |
727 | /* | |
728 | * Keep the 'A' override for percpu symbols to | |
729 | * ensure consistent behavior compared to older | |
730 | * versions of this tool. | |
731 | */ | |
c6bda7c9 | 732 | table[i].sym[0] = 'A'; |
8c996940 AB |
733 | table[i].percpu_absolute = 1; |
734 | } | |
c6bda7c9 RR |
735 | } |
736 | ||
2213e9a6 AB |
737 | /* find the minimum non-absolute symbol address */ |
738 | static void record_relative_base(void) | |
739 | { | |
740 | unsigned int i; | |
741 | ||
742 | relative_base = -1ULL; | |
743 | for (i = 0; i < table_cnt; i++) | |
744 | if (!symbol_absolute(&table[i]) && | |
745 | table[i].addr < relative_base) | |
746 | relative_base = table[i].addr; | |
747 | } | |
748 | ||
b3dbb4ec | 749 | int main(int argc, char **argv) |
1da177e4 | 750 | { |
41f11a4f YS |
751 | if (argc >= 2) { |
752 | int i; | |
753 | for (i = 1; i < argc; i++) { | |
754 | if(strcmp(argv[i], "--all-symbols") == 0) | |
755 | all_symbols = 1; | |
c6bda7c9 RR |
756 | else if (strcmp(argv[i], "--absolute-percpu") == 0) |
757 | absolute_percpu = 1; | |
41f11a4f YS |
758 | else if (strncmp(argv[i], "--symbol-prefix=", 16) == 0) { |
759 | char *p = &argv[i][16]; | |
760 | /* skip quote */ | |
761 | if ((*p == '"' && *(p+2) == '"') || (*p == '\'' && *(p+2) == '\'')) | |
762 | p++; | |
763 | symbol_prefix_char = *p; | |
2213e9a6 AB |
764 | } else if (strcmp(argv[i], "--base-relative") == 0) |
765 | base_relative = 1; | |
766 | else | |
41f11a4f YS |
767 | usage(); |
768 | } | |
769 | } else if (argc != 1) | |
1da177e4 LT |
770 | usage(); |
771 | ||
772 | read_map(stdin); | |
c6bda7c9 RR |
773 | if (absolute_percpu) |
774 | make_percpus_absolute(); | |
2213e9a6 AB |
775 | if (base_relative) |
776 | record_relative_base(); | |
2ea03891 SR |
777 | sort_symbols(); |
778 | optimize_token_table(); | |
1da177e4 LT |
779 | write_src(); |
780 | ||
781 | return 0; | |
782 | } |