3a69b3ac |
1 | /* a.out object file format |
2 | Copyright (C) 1989, 1990, 1991 Free Software Foundation, Inc. |
3 | |
4 | This file is part of GAS, the GNU Assembler. |
5 | |
6 | GAS is free software; you can redistribute it and/or modify |
7 | it under the terms of the GNU General Public License as |
8 | published by the Free Software Foundation; either version 1, |
9 | or (at your option) any later version. |
10 | |
11 | GAS is distributed in the hope that it will be useful, but |
12 | WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
14 | the GNU General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU General Public |
17 | License along with GAS; see the file COPYING. If not, write |
18 | to the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ |
19 | |
20 | /* $Id$ */ |
21 | |
22 | #include "as.h" |
23 | |
24 | #include "obstack.h" |
25 | |
26 | /* in: segT out: N_TYPE bits */ |
27 | const short seg_N_TYPE[] = { |
28 | N_ABS, |
29 | N_TEXT, |
30 | N_DATA, |
31 | N_BSS, |
32 | N_UNDF, /* unknown */ |
33 | N_UNDF, /* absent */ |
34 | N_UNDF, /* pass1 */ |
35 | N_UNDF, /* error */ |
36 | N_UNDF, /* bignum/flonum */ |
37 | N_UNDF, /* difference */ |
38 | N_UNDF, /* debug */ |
39 | N_UNDF, /* ntv */ |
40 | N_UNDF, /* ptv */ |
41 | N_REGISTER, /* register */ |
42 | }; |
43 | |
44 | const segT N_TYPE_seg [N_TYPE+2] = { /* N_TYPE == 0x1E = 32-2 */ |
45 | SEG_UNKNOWN, /* N_UNDF == 0 */ |
46 | SEG_GOOF, |
47 | SEG_ABSOLUTE, /* N_ABS == 2 */ |
48 | SEG_GOOF, |
49 | SEG_TEXT, /* N_TEXT == 4 */ |
50 | SEG_GOOF, |
51 | SEG_DATA, /* N_DATA == 6 */ |
52 | SEG_GOOF, |
53 | SEG_BSS, /* N_BSS == 8 */ |
54 | SEG_GOOF, |
55 | SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, |
56 | SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, |
57 | SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, |
58 | SEG_REGISTER, /* dummy N_REGISTER for regs = 30 */ |
59 | SEG_GOOF, |
60 | }; |
61 | |
62 | #ifdef __STDC__ |
63 | static void obj_aout_stab(int what); |
64 | static void obj_aout_line(void); |
65 | static void obj_aout_desc(void); |
66 | #else /* __STDC__ */ |
67 | static void obj_aout_desc(); |
68 | static void obj_aout_stab(); |
69 | static void obj_aout_line(); |
70 | #endif /* __STDC__ */ |
71 | |
72 | const pseudo_typeS obj_pseudo_table[] = { |
73 | { "line", obj_aout_line, 0 }, /* source code line number */ |
74 | { "ln", obj_aout_line, 0 }, /* source code line number */ |
75 | { "desc", obj_aout_desc, 0 }, /* def */ |
76 | { "stabd", obj_aout_stab, 'd' }, /* stabs */ |
77 | { "stabn", obj_aout_stab, 'n' }, /* stabs */ |
78 | { "stabs", obj_aout_stab, 's' }, /* stabs */ |
79 | |
80 | { NULL} /* end sentinel */ |
81 | }; /* obj_pseudo_table */ |
82 | |
83 | |
84 | /* Relocation. */ |
85 | |
86 | /* |
87 | * In: length of relocation (or of address) in chars: 1, 2 or 4. |
88 | * Out: GNU LD relocation length code: 0, 1, or 2. |
89 | */ |
90 | |
91 | static unsigned char |
92 | nbytes_r_length [] = { |
93 | 42, 0, 1, 42, 2 |
94 | }; |
95 | |
96 | /* |
97 | * emit_relocations() |
98 | * |
99 | * Crawl along a fixS chain. Emit the segment's relocations. |
100 | */ |
101 | void obj_emit_relocations(where, fixP, segment_address_in_file) |
102 | char **where; |
103 | fixS *fixP; /* Fixup chain for this segment. */ |
104 | relax_addressT segment_address_in_file; |
105 | { |
106 | struct reloc_info_generic ri; |
107 | register symbolS *symbolP; |
108 | |
109 | /* If a machine dependent emitter is needed, call it instead. */ |
110 | if (md_emit_relocations) { |
111 | (*md_emit_relocations) (fixP, segment_address_in_file); |
112 | return; |
113 | } |
114 | |
115 | /* JF this is for paranoia */ |
116 | bzero((char *)&ri,sizeof(ri)); |
117 | for (; fixP; fixP = fixP->fx_next) { |
118 | if ((symbolP = fixP->fx_addsy) != 0) { |
119 | ri.r_bsr = fixP->fx_bsr; |
120 | ri.r_disp = fixP->fx_im_disp; |
121 | ri.r_callj = fixP->fx_callj; |
122 | ri.r_length = nbytes_r_length [fixP->fx_size]; |
123 | ri.r_pcrel = fixP->fx_pcrel; |
124 | ri.r_address = fixP->fx_frag->fr_address + fixP->fx_where - segment_address_in_file; |
125 | |
126 | if (S_GET_TYPE(symbolP) == N_UNDF) { |
127 | ri.r_extern = 1; |
128 | ri.r_symbolnum = symbolP->sy_number; |
129 | } else { |
130 | ri.r_extern = 0; |
131 | ri.r_symbolnum = S_GET_TYPE(symbolP); |
132 | } |
133 | |
134 | /* Output the relocation information in machine-dependent form. */ |
135 | md_ri_to_chars(*where, &ri); |
136 | *where += md_reloc_size; |
137 | } /* if there is an add symbol */ |
138 | } /* for each fix */ |
139 | |
140 | return; |
141 | } /* emit_relocations() */ |
142 | |
143 | /* Aout file generation & utilities */ |
144 | void obj_header_append(where, headers) |
145 | char **where; |
146 | object_headers *headers; |
147 | { |
148 | tc_headers_hook(headers); |
149 | |
150 | #ifdef CROSS_ASSEMBLE |
151 | md_number_to_chars(*where, headers->header.a_info, sizeof(headers->header.a_info)); |
152 | *where += sizeof(headers->header.a_info); |
153 | md_number_to_chars(*where, headers->header.a_text, sizeof(headers->header.a_text)); |
154 | *where += sizeof(headers->header.a_text); |
155 | md_number_to_chars(*where, headers->header.a_data, sizeof(headers->header.a_data)); |
156 | *where += sizeof(headers->header.a_data); |
157 | md_number_to_chars(*where, headers->header.a_bss, sizeof(headers->header.a_bss)); |
158 | *where += sizeof(headers->header.a_bss); |
159 | md_number_to_chars(*where, headers->header.a_syms, sizeof(headers->header.a_syms)); |
160 | *where += sizeof(headers->header.a_syms); |
161 | md_number_to_chars(*where, headers->header.a_entry, sizeof(headers->header.a_entry)); |
162 | *where += sizeof(headers->header.a_entry); |
163 | md_number_to_chars(*where, headers->header.a_trsize, sizeof(headers->header.a_trsize)); |
164 | *where += sizeof(headers->header.a_trsize); |
165 | md_number_to_chars(*where, headers->header.a_drsize, sizeof(headers->header.a_drsize)); |
166 | *where += sizeof(headers->header.a_drsize); |
167 | #ifdef EXEC_MACHINE_TYPE |
168 | md_number_to_chars(*where, headers->header.a_machtype, sizeof(headers->header.a_machtype)); |
169 | *where += sizeof(headers->header.a_machtype); |
170 | #endif /* EXEC_MACHINE_TYPE */ |
171 | #ifdef EXEC_VERSION |
172 | md_number_to_chars(*where, headers->header.a_version, sizeof(headers->header.a_version)); |
173 | *where += sizeof(headers->header.a_version); |
174 | #endif /* EXEC_VERSION */ |
175 | |
176 | #else /* CROSS_ASSEMBLE */ |
177 | |
178 | append(where, (char *) &headers->header, sizeof(headers->header)); |
179 | #endif /* CROSS_ASSEMBLE */ |
180 | |
181 | return; |
182 | } /* obj_append_header() */ |
183 | |
184 | void obj_symbol_to_chars(where, symbolP) |
185 | char **where; |
186 | symbolS *symbolP; |
187 | { |
188 | md_number_to_chars((char *)&(S_GET_OFFSET(symbolP)), S_GET_OFFSET(symbolP), sizeof(S_GET_OFFSET(symbolP))); |
189 | md_number_to_chars((char *)&(S_GET_DESC(symbolP)), S_GET_DESC(symbolP), sizeof(S_GET_DESC(symbolP))); |
190 | md_number_to_chars((char *)&(S_GET_VALUE(symbolP)), S_GET_VALUE(symbolP), sizeof(S_GET_VALUE(symbolP))); |
191 | |
192 | append(where, (char *)&symbolP->sy_symbol, sizeof(obj_symbol_type)); |
193 | } /* obj_symbol_to_chars() */ |
194 | |
195 | void obj_emit_symbols(where, symbol_rootP) |
196 | char **where; |
197 | symbolS *symbol_rootP; |
198 | { |
199 | symbolS * symbolP; |
200 | |
201 | /* |
202 | * Emit all symbols left in the symbol chain. |
203 | */ |
204 | for(symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) { |
205 | /* Used to save the offset of the name. It is used to point |
206 | to the string in memory but must be a file offset. */ |
207 | register char *temp; |
208 | |
209 | temp = S_GET_NAME(symbolP); |
210 | S_SET_OFFSET(symbolP, symbolP->sy_name_offset); |
211 | |
212 | /* Any symbol still undefined and is not a dbg symbol is made N_EXT. */ |
213 | if (!S_IS_DEBUG(symbolP) && !S_IS_DEFINED(symbolP)) S_SET_EXTERNAL(symbolP); |
214 | |
215 | obj_symbol_to_chars(where, symbolP); |
216 | S_SET_NAME(symbolP,temp); |
217 | } |
218 | } /* emit_symbols() */ |
219 | |
220 | void obj_symbol_new_hook(symbolP) |
221 | symbolS *symbolP; |
222 | { |
223 | S_SET_OTHER(symbolP, 0); |
224 | S_SET_DESC(symbolP, 0); |
225 | return; |
226 | } /* obj_symbol_new_hook() */ |
227 | |
228 | static void obj_aout_line() { |
229 | /* Assume delimiter is part of expression. */ |
230 | /* BSD4.2 as fails with delightful bug, so we */ |
231 | /* are not being incompatible here. */ |
232 | new_logical_line((char *)NULL, (int)(get_absolute_expression())); |
233 | demand_empty_rest_of_line(); |
234 | } /* obj_aout_line() */ |
235 | |
236 | /* |
237 | * stab() |
238 | * |
239 | * Handle .stabX directives, which used to be open-coded. |
240 | * So much creeping featurism overloaded the semantics that we decided |
241 | * to put all .stabX thinking in one place. Here. |
242 | * |
243 | * We try to make any .stabX directive legal. Other people's AS will often |
244 | * do assembly-time consistency checks: eg assigning meaning to n_type bits |
245 | * and "protecting" you from setting them to certain values. (They also zero |
246 | * certain bits before emitting symbols. Tut tut.) |
247 | * |
248 | * If an expression is not absolute we either gripe or use the relocation |
249 | * information. Other people's assemblers silently forget information they |
250 | * don't need and invent information they need that you didn't supply. |
251 | * |
252 | * .stabX directives always make a symbol table entry. It may be junk if |
253 | * the rest of your .stabX directive is malformed. |
254 | */ |
255 | static void obj_aout_stab(what) |
256 | int what; |
257 | { |
258 | register symbolS * symbolP = 0; |
259 | register char * string; |
260 | int saved_type = 0; |
261 | int length; |
262 | int goof; /* TRUE if we have aborted. */ |
263 | long longint; |
264 | |
265 | /* |
266 | * Enter with input_line_pointer pointing past .stabX and any following |
267 | * whitespace. |
268 | */ |
269 | goof = 0; /* JF who forgot this?? */ |
270 | if (what == 's') { |
271 | string = demand_copy_C_string(& length); |
272 | SKIP_WHITESPACE(); |
273 | if (* input_line_pointer == ',') |
274 | input_line_pointer ++; |
275 | else { |
276 | as_bad("I need a comma after symbol's name"); |
277 | goof = 1; |
278 | } |
279 | } else |
280 | string = ""; |
281 | |
282 | /* |
283 | * Input_line_pointer->after ','. String->symbol name. |
284 | */ |
285 | if (! goof) { |
286 | symbolP = symbol_new(string, |
287 | SEG_UNKNOWN, |
288 | 0, |
289 | (struct frag *)0); |
290 | switch (what) { |
291 | case 'd': |
292 | S_SET_NAME(symbolP, NULL); /* .stabd feature. */ |
293 | S_SET_VALUE(symbolP, obstack_next_free(&frags) - frag_now->fr_literal); |
294 | symbolP->sy_frag = frag_now; |
295 | break; |
296 | |
297 | case 'n': |
298 | symbolP->sy_frag = &zero_address_frag; |
299 | break; |
300 | |
301 | case 's': |
302 | symbolP->sy_frag = & zero_address_frag; |
303 | break; |
304 | |
305 | default: |
306 | BAD_CASE(what); |
307 | break; |
308 | } |
309 | |
310 | if (get_absolute_expression_and_terminator(&longint) == ',') |
311 | symbolP->sy_symbol.n_type = saved_type = longint; |
312 | else { |
313 | as_bad("I want a comma after the n_type expression"); |
314 | goof = 1; |
315 | input_line_pointer --; /* Backup over a non-',' char. */ |
316 | } |
317 | } |
318 | |
319 | if (!goof) { |
320 | if (get_absolute_expression_and_terminator(&longint) == ',') |
321 | S_SET_OTHER(symbolP, longint); |
322 | else { |
323 | as_bad("I want a comma after the n_other expression"); |
324 | goof = 1; |
325 | input_line_pointer--; /* Backup over a non-',' char. */ |
326 | } |
327 | } |
328 | |
329 | if (!goof) { |
330 | S_SET_DESC(symbolP, get_absolute_expression()); |
331 | if (what == 's' || what == 'n') { |
332 | if (*input_line_pointer != ',') { |
333 | as_bad("I want a comma after the n_desc expression"); |
334 | goof = 1; |
335 | } else { |
336 | input_line_pointer++; |
337 | } |
338 | } |
339 | } |
340 | |
341 | if ((!goof) && (what=='s' || what=='n')) { |
342 | pseudo_set(symbolP); |
343 | symbolP->sy_symbol.n_type = saved_type; |
344 | } |
345 | |
346 | if (goof) |
347 | ignore_rest_of_line(); |
348 | else |
349 | demand_empty_rest_of_line (); |
350 | } /* obj_aout_stab() */ |
351 | |
352 | static void obj_aout_desc() { |
353 | register char *name; |
354 | register char c; |
355 | register char *p; |
356 | register symbolS *symbolP; |
357 | register int temp; |
358 | |
359 | /* |
360 | * Frob invented at RMS' request. Set the n_desc of a symbol. |
361 | */ |
362 | name = input_line_pointer; |
363 | c = get_symbol_end(); |
364 | p = input_line_pointer; |
365 | * p = c; |
366 | SKIP_WHITESPACE(); |
367 | if (*input_line_pointer != ',') { |
368 | *p = 0; |
369 | as_bad("Expected comma after name \"%s\"", name); |
370 | *p = c; |
371 | ignore_rest_of_line(); |
372 | } else { |
373 | input_line_pointer ++; |
374 | temp = get_absolute_expression(); |
375 | *p = 0; |
376 | symbolP = symbol_find_or_make(name); |
377 | *p = c; |
378 | S_SET_DESC(symbolP,temp); |
379 | } |
380 | demand_empty_rest_of_line(); |
381 | } /* obj_aout_desc() */ |
382 | |
383 | void obj_read_begin_hook() { |
384 | return; |
385 | } /* obj_read_begin_hook() */ |
386 | |
387 | void obj_crawl_symbol_chain(headers) |
388 | object_headers *headers; |
389 | { |
390 | symbolS *symbolP; |
391 | symbolS **symbolPP; |
392 | int symbol_number = 0; |
393 | |
394 | /* JF deal with forward references first... */ |
395 | for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) { |
396 | if (symbolP->sy_forward) { |
397 | S_SET_VALUE(symbolP, S_GET_VALUE(symbolP) |
398 | + S_GET_VALUE(symbolP->sy_forward) |
399 | + symbolP->sy_forward->sy_frag->fr_address); |
400 | |
401 | symbolP->sy_forward=0; |
402 | } /* if it has a forward reference */ |
403 | } /* walk the symbol chain */ |
404 | |
405 | tc_crawl_symbol_chain(headers); |
406 | |
407 | symbolPP = &symbol_rootP; /*->last symbol chain link. */ |
408 | while ((symbolP = *symbolPP) != NULL) { |
409 | if (flagseen['R'] && (S_GET_SEGMENT(symbolP) == SEG_DATA)) { |
410 | S_SET_SEGMENT(symbolP, SEG_TEXT); |
411 | } /* if pusing data into text */ |
412 | |
413 | S_SET_VALUE(symbolP, S_GET_VALUE(symbolP) + symbolP->sy_frag->fr_address); |
414 | |
415 | /* OK, here is how we decide which symbols go out into the |
416 | brave new symtab. Symbols that do are: |
417 | |
418 | * symbols with no name (stabd's?) |
419 | * symbols with debug info in their N_TYPE |
420 | |
421 | Symbols that don't are: |
422 | * symbols that are registers |
423 | * symbols with \1 as their 3rd character (numeric labels) |
424 | * "local labels" as defined by S_LOCAL_NAME(name) |
425 | if the -L switch was passed to gas. |
426 | |
427 | All other symbols are output. We complain if a deleted |
428 | symbol was marked external. */ |
429 | |
430 | |
431 | if (!S_IS_REGISTER(symbolP) |
432 | && (!S_GET_NAME(symbolP) |
433 | || S_IS_DEBUG(symbolP) |
434 | #ifdef TC_I960 |
435 | /* FIXME-SOON this ifdef seems highly dubious to me. xoxorich. */ |
436 | || !S_IS_DEFINED(symbolP) |
437 | || S_IS_EXTERNAL(symbolP) |
438 | #endif /* TC_I960 */ |
439 | || (S_GET_NAME(symbolP)[0] != '\001' && (flagseen ['L'] || ! S_LOCAL_NAME(symbolP))))) { |
440 | symbolP->sy_number = symbol_number++; |
441 | |
442 | /* The + 1 after strlen account for the \0 at the |
443 | end of each string */ |
444 | if (!S_IS_STABD(symbolP)) { |
445 | /* Ordinary case. */ |
446 | symbolP->sy_name_offset = string_byte_count; |
447 | string_byte_count += strlen(S_GET_NAME(symbolP)) + 1; |
448 | } |
449 | else /* .Stabd case. */ |
450 | symbolP->sy_name_offset = 0; |
451 | symbolPP = &(symbol_next(symbolP)); |
452 | } else { |
453 | if (S_IS_EXTERNAL(symbolP) || !S_IS_DEFINED(symbolP)) { |
454 | as_bad("Local symbol %s never defined", S_GET_NAME(symbolP)); |
455 | } /* oops. */ |
456 | |
457 | /* Unhook it from the chain */ |
458 | *symbolPP = symbol_next(symbolP); |
459 | } /* if this symbol should be in the output */ |
460 | } /* for each symbol */ |
461 | |
462 | H_SET_SYMBOL_TABLE_SIZE(headers, symbol_number); |
463 | |
464 | return; |
465 | } /* obj_crawl_symbol_chain() */ |
466 | |
467 | /* |
468 | * Find strings by crawling along symbol table chain. |
469 | */ |
470 | |
471 | void obj_emit_strings(where) |
472 | char **where; |
473 | { |
474 | symbolS *symbolP; |
475 | |
476 | #ifdef CROSS_ASSEMBLE |
477 | /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */ |
478 | md_number_to_chars(*where, string_byte_count, sizeof(string_byte_count)); |
479 | *where += sizeof(string_byte_count); |
480 | #else /* CROSS_ASSEMBLE */ |
481 | append (where, (char *)&string_byte_count, (unsigned long)sizeof(string_byte_count)); |
482 | #endif /* CROSS_ASSEMBLE */ |
483 | |
484 | for(symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) { |
485 | if(S_GET_NAME(symbolP)) |
486 | append(&next_object_file_charP, S_GET_NAME(symbolP), |
487 | (unsigned long)(strlen (S_GET_NAME(symbolP)) + 1)); |
488 | } /* walk symbol chain */ |
489 | |
490 | return; |
491 | } /* obj_emit_strings() */ |
492 | |
493 | /* |
494 | * Local Variables: |
495 | * comment-column: 0 |
496 | * fill-column: 131 |
497 | * End: |
498 | */ |
499 | |
500 | /* end of obj-aout.c */ |