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 */