1 /* a.out object file format
2 Copyright (C) 1989, 1990, 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
4 This file is part of GAS, the GNU Assembler.
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 2,
9 or (at your option) any later version.
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.
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. */
23 #include "aout/aout64.h"
28 /* in: segT out: N_TYPE bits */
29 const short seg_N_TYPE[] =
37 N_UNDF, /* expression */
41 N_REGISTER, /* register */
44 const segT N_TYPE_seg[N_TYPE + 2] =
45 { /* N_TYPE == 0x1E = 32-2 */
46 SEG_UNKNOWN, /* N_UNDF == 0 */
48 SEG_ABSOLUTE, /* N_ABS == 2 */
50 SEG_TEXT, /* N_TEXT == 4 */
52 SEG_DATA, /* N_DATA == 6 */
54 SEG_BSS, /* N_BSS == 8 */
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, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
58 SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
59 SEG_REGISTER, /* dummy N_REGISTER for regs = 30 */
64 static void obj_aout_line PARAMS ((int));
65 static void obj_aout_weak PARAMS ((int));
67 const pseudo_typeS obj_pseudo_table[] =
69 {"line", obj_aout_line, 0}, /* source code line number */
70 {"ln", obj_aout_line, 0}, /* coff line number that we use anyway */
72 {"weak", obj_aout_weak, 0}, /* mark symbol as weak. */
74 /* coff debug pseudos (ignored) */
77 {"endef", s_ignore, 0},
78 {"ident", s_ignore, 0},
79 {"line", s_ignore, 0},
82 {"size", s_ignore, 0},
84 {"type", s_ignore, 0},
86 {"version", s_ignore, 0},
88 {"optim", s_ignore, 0}, /* For sun386i cc (?) */
91 {"ABORT", s_abort, 0},
93 {NULL} /* end sentinel */
94 }; /* obj_pseudo_table */
100 obj_aout_frob_symbol (sym, punt)
106 int desc, type, other;
108 flags = sym->bsym->flags;
109 desc = S_GET_DESC (sym);
110 type = S_GET_TYPE (sym);
111 other = S_GET_OTHER (sym);
112 sec = sym->bsym->section;
114 /* Only frob simple symbols this way right now. */
115 if (! (type & ~ (N_TYPE | N_EXT)))
117 if (type == (N_UNDF | N_EXT)
118 && sec == &bfd_abs_section)
119 sym->bsym->section = sec = bfd_und_section_ptr;
121 if ((type & N_TYPE) != N_INDR
122 && (type & N_TYPE) != N_SETA
123 && (type & N_TYPE) != N_SETT
124 && (type & N_TYPE) != N_SETD
125 && (type & N_TYPE) != N_SETB
127 && (sec == &bfd_abs_section
128 || sec == &bfd_und_section))
130 if (flags & BSF_EXPORT)
133 switch (type & N_TYPE)
139 /* Set the debugging flag for constructor symbols so that
140 BFD leaves them alone. */
141 sym->bsym->flags |= BSF_DEBUGGING;
143 /* You can't put a common symbol in a set. The way a set
144 element works is that the symbol has a definition and a
145 name, and the linker adds the definition to the set of
146 that name. That does not work for a common symbol,
147 because the linker can't tell which common symbol the
148 user means. FIXME: Using as_bad here may be
149 inappropriate, since the user may want to force a
150 particular type without regard to the semantics of sets;
151 on the other hand, we certainly don't want anybody to be
152 mislead into thinking that their code will work. */
153 if (S_IS_COMMON (sym))
154 as_bad ("Attempt to put a common symbol into set %s",
156 /* Similarly, you can't put an undefined symbol in a set. */
157 else if (! S_IS_DEFINED (sym))
158 as_bad ("Attempt to put an undefined symbol into set %s",
163 /* Put indirect symbols in the indirect section. */
164 sym->bsym->section = bfd_ind_section_ptr;
165 sym->bsym->flags |= BSF_INDIRECT;
168 sym->bsym->flags |= BSF_EXPORT;
169 sym->bsym->flags &=~ BSF_LOCAL;
173 /* Mark warning symbols. */
174 sym->bsym->flags |= BSF_WARNING;
180 sym->bsym->flags |= BSF_DEBUGGING;
183 S_SET_TYPE (sym, type);
185 /* Double check weak symbols. */
186 if (sym->bsym->flags & BSF_WEAK)
188 if (S_IS_COMMON (sym))
189 as_bad ("Symbol `%s' can not be both weak and common",
195 obj_aout_frob_file ()
197 /* Relocation processing may require knowing the VMAs of the sections.
198 Since writing to a section will cause the BFD back end to compute the
199 VMAs, fake it out here.... */
202 if (bfd_section_size (stdoutput, text_section) != 0)
204 x = bfd_set_section_contents (stdoutput, text_section, &b, (file_ptr) 0,
207 else if (bfd_section_size (stdoutput, data_section) != 0)
209 x = bfd_set_section_contents (stdoutput, data_section, &b, (file_ptr) 0,
222 * Crawl along a fixS chain. Emit the segment's relocations.
225 obj_emit_relocations (where, fixP, segment_address_in_file)
227 fixS *fixP; /* Fixup chain for this segment. */
228 relax_addressT segment_address_in_file;
230 for (; fixP; fixP = fixP->fx_next)
231 if (fixP->fx_done == 0)
233 tc_aout_fix_to_chars (*where, fixP, segment_address_in_file);
234 *where += md_reloc_size;
238 #ifndef obj_header_append
239 /* Aout file generation & utilities */
241 obj_header_append (where, headers)
243 object_headers *headers;
245 tc_headers_hook (headers);
248 md_number_to_chars (*where, headers->header.a_info, sizeof (headers->header.a_info));
249 *where += sizeof (headers->header.a_info);
250 md_number_to_chars (*where, headers->header.a_text, sizeof (headers->header.a_text));
251 *where += sizeof (headers->header.a_text);
252 md_number_to_chars (*where, headers->header.a_data, sizeof (headers->header.a_data));
253 *where += sizeof (headers->header.a_data);
254 md_number_to_chars (*where, headers->header.a_bss, sizeof (headers->header.a_bss));
255 *where += sizeof (headers->header.a_bss);
256 md_number_to_chars (*where, headers->header.a_syms, sizeof (headers->header.a_syms));
257 *where += sizeof (headers->header.a_syms);
258 md_number_to_chars (*where, headers->header.a_entry, sizeof (headers->header.a_entry));
259 *where += sizeof (headers->header.a_entry);
260 md_number_to_chars (*where, headers->header.a_trsize, sizeof (headers->header.a_trsize));
261 *where += sizeof (headers->header.a_trsize);
262 md_number_to_chars (*where, headers->header.a_drsize, sizeof (headers->header.a_drsize));
263 *where += sizeof (headers->header.a_drsize);
265 #else /* CROSS_COMPILE */
267 append (where, (char *) &headers->header, sizeof (headers->header));
268 #endif /* CROSS_COMPILE */
274 obj_symbol_to_chars (where, symbolP)
278 md_number_to_chars ((char *) &(S_GET_OFFSET (symbolP)), S_GET_OFFSET (symbolP), sizeof (S_GET_OFFSET (symbolP)));
279 md_number_to_chars ((char *) &(S_GET_DESC (symbolP)), S_GET_DESC (symbolP), sizeof (S_GET_DESC (symbolP)));
280 md_number_to_chars ((char *) &(symbolP->sy_symbol.n_value), S_GET_VALUE (symbolP), sizeof (symbolP->sy_symbol.n_value));
282 append (where, (char *) &symbolP->sy_symbol, sizeof (obj_symbol_type));
286 obj_emit_symbols (where, symbol_rootP)
288 symbolS *symbol_rootP;
292 /* Emit all symbols left in the symbol chain. */
293 for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
295 /* Used to save the offset of the name. It is used to point
296 to the string in memory but must be a file offset. */
299 temp = S_GET_NAME (symbolP);
300 S_SET_OFFSET (symbolP, symbolP->sy_name_offset);
302 /* Any symbol still undefined and is not a dbg symbol is made N_EXT. */
303 if (!S_IS_DEBUG (symbolP) && !S_IS_DEFINED (symbolP))
304 S_SET_EXTERNAL (symbolP);
306 /* Adjust the type of a weak symbol. */
307 if (S_GET_WEAK (symbolP))
309 switch (S_GET_TYPE (symbolP))
311 case N_UNDF: S_SET_TYPE (symbolP, N_WEAKU); break;
312 case N_ABS: S_SET_TYPE (symbolP, N_WEAKA); break;
313 case N_TEXT: S_SET_TYPE (symbolP, N_WEAKT); break;
314 case N_DATA: S_SET_TYPE (symbolP, N_WEAKD); break;
315 case N_BSS: S_SET_TYPE (symbolP, N_WEAKB); break;
316 default: as_bad ("%s: bad type for weak symbol", temp); break;
320 obj_symbol_to_chars (where, symbolP);
321 S_SET_NAME (symbolP, temp);
325 #endif /* ! BFD_ASSEMBLER */
328 obj_aout_line (ignore)
331 /* Assume delimiter is part of expression.
332 BSD4.2 as fails with delightful bug, so we
333 are not being incompatible here. */
334 new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
335 demand_empty_rest_of_line ();
336 } /* obj_aout_line() */
338 /* Handle .weak. This is a GNU extension. */
341 obj_aout_weak (ignore)
350 name = input_line_pointer;
351 c = get_symbol_end ();
352 symbolP = symbol_find_or_make (name);
353 *input_line_pointer = c;
355 S_SET_WEAK (symbolP);
358 input_line_pointer++;
360 if (*input_line_pointer == '\n')
365 demand_empty_rest_of_line ();
369 obj_read_begin_hook ()
373 #ifndef BFD_ASSEMBLER
376 obj_crawl_symbol_chain (headers)
377 object_headers *headers;
381 int symbol_number = 0;
383 tc_crawl_symbol_chain (headers);
385 symbolPP = &symbol_rootP; /*->last symbol chain link. */
386 while ((symbolP = *symbolPP) != NULL)
388 if (flag_readonly_data_in_text && (S_GET_SEGMENT (symbolP) == SEG_DATA))
390 S_SET_SEGMENT (symbolP, SEG_TEXT);
391 } /* if pusing data into text */
393 resolve_symbol_value (symbolP);
395 /* OK, here is how we decide which symbols go out into the brave
396 new symtab. Symbols that do are:
398 * symbols with no name (stabd's?)
399 * symbols with debug info in their N_TYPE
401 Symbols that don't are:
402 * symbols that are registers
403 * symbols with \1 as their 3rd character (numeric labels)
404 * "local labels" as defined by S_LOCAL_NAME(name) if the -L
405 switch was passed to gas.
407 All other symbols are output. We complain if a deleted
408 symbol was marked external. */
411 if (!S_IS_REGISTER (symbolP)
412 && (!S_GET_NAME (symbolP)
413 || S_IS_DEBUG (symbolP)
414 || !S_IS_DEFINED (symbolP)
415 || S_IS_EXTERNAL (symbolP)
416 || (S_GET_NAME (symbolP)[0] != '\001'
417 && (flag_keep_locals || !S_LOCAL_NAME (symbolP)))))
419 symbolP->sy_number = symbol_number++;
421 /* The + 1 after strlen account for the \0 at the
422 end of each string */
423 if (!S_IS_STABD (symbolP))
426 symbolP->sy_name_offset = string_byte_count;
427 string_byte_count += strlen (S_GET_NAME (symbolP)) + 1;
429 else /* .Stabd case. */
430 symbolP->sy_name_offset = 0;
431 symbolPP = &(symbol_next (symbolP));
435 if (S_IS_EXTERNAL (symbolP) || !S_IS_DEFINED (symbolP))
436 /* This warning should never get triggered any more.
437 Well, maybe if you're doing twisted things with
440 as_bad ("Local symbol %s never defined.", decode_local_label_name (S_GET_NAME (symbolP)));
443 /* Unhook it from the chain */
444 *symbolPP = symbol_next (symbolP);
445 } /* if this symbol should be in the output */
446 } /* for each symbol */
448 H_SET_SYMBOL_TABLE_SIZE (headers, symbol_number);
452 * Find strings by crawling along symbol table chain.
456 obj_emit_strings (where)
462 /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */
463 md_number_to_chars (*where, string_byte_count, sizeof (string_byte_count));
464 *where += sizeof (string_byte_count);
465 #else /* CROSS_COMPILE */
466 append (where, (char *) &string_byte_count, (unsigned long) sizeof (string_byte_count));
467 #endif /* CROSS_COMPILE */
469 for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
471 if (S_GET_NAME (symbolP))
472 append (&next_object_file_charP, S_GET_NAME (symbolP),
473 (unsigned long) (strlen (S_GET_NAME (symbolP)) + 1));
474 } /* walk symbol chain */
478 #define AOUT_VERSION 0
482 obj_pre_write_hook (headers)
483 object_headers *headers;
485 H_SET_DYNAMIC (headers, 0);
486 H_SET_VERSION (headers, AOUT_VERSION);
487 H_SET_MACHTYPE (headers, AOUT_MACHTYPE);
488 tc_aout_pre_write_hook (headers);
494 /* Strip out the section name */
496 char *section_name_end;
503 section_name = input_line_pointer;
504 c = get_symbol_end ();
505 section_name_end = input_line_pointer;
507 len = section_name_end - section_name;
508 input_line_pointer++;
509 save = input_line_pointer;
514 exp = get_absolute_expression ();
516 else if (*input_line_pointer == ',')
518 input_line_pointer++;
519 exp = get_absolute_expression ();
523 input_line_pointer = save;
528 as_bad ("subsegment index too high");
531 if (strcmp (section_name, ".text") == 0)
533 subseg_set (SEG_TEXT, (subsegT) exp);
536 if (strcmp (section_name, ".data") == 0)
538 if (flag_readonly_data_in_text)
539 subseg_set (SEG_TEXT, (subsegT) exp + 1000);
541 subseg_set (SEG_DATA, (subsegT) exp);
544 *section_name_end = c;
547 #endif /* ! BFD_ASSEMBLER */
549 /* end of obj-aout.c */