1 /* b.out object file format
2 Copyright (C) 1989, 1990, 1991, 1992 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. */
22 #include "aout/stab_gnu.h"
23 const short /* in: segT out: N_TYPE bits */
33 N_UNDF
, /* bignum/flonum */
34 N_UNDF
, /* difference */
35 N_REGISTER
, /* register */
38 const segT N_TYPE_seg
[N_TYPE
+2] = { /* N_TYPE == 0x1E = 32-2 */
39 SEG_UNKNOWN
, /* N_UNDF == 0 */
41 SEG_ABSOLUTE
, /* N_ABS == 2 */
43 SEG_TEXT
, /* N_TEXT == 4 */
45 SEG_DATA
, /* N_DATA == 6 */
47 SEG_BSS
, /* N_BSS == 8 */
49 SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
,
50 SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
,
51 SEG_GOOF
, SEG_GOOF
, SEG_GOOF
, SEG_GOOF
,
52 SEG_REGISTER
, /* dummy N_REGISTER for regs = 30 */
57 static void obj_bout_stab(int what
);
58 static void obj_bout_line(void);
59 static void obj_bout_desc(void);
60 #else /* not __STDC__ */
61 static void obj_bout_desc();
62 static void obj_bout_stab();
63 static void obj_bout_line();
64 #endif /* not __STDC__ */
66 const pseudo_typeS obj_pseudo_table
[] = {
67 /* stabs (aka a.out aka b.out directives for debug symbols) */
68 { "desc", obj_bout_desc
, 0 }, /* def */
69 { "line", obj_bout_line
, 0 }, /* source code line number */
70 { "stabd", obj_bout_stab
, 'd' }, /* stabs */
71 { "stabn", obj_bout_stab
, 'n' }, /* stabs */
72 { "stabs", obj_bout_stab
, 's' }, /* stabs */
74 /* coff debugging directives. Currently ignored silently */
75 { "def", s_ignore
, 0 },
76 { "dim", s_ignore
, 0 },
77 { "endef", s_ignore
, 0 },
78 { "ln", s_ignore
, 0 },
79 { "scl", s_ignore
, 0 },
80 { "size", s_ignore
, 0 },
81 { "tag", s_ignore
, 0 },
82 { "type", s_ignore
, 0 },
83 { "val", s_ignore
, 0 },
85 /* other stuff we don't handle */
86 { "ABORT", s_ignore
, 0 },
87 { "ident", s_ignore
, 0 },
89 { NULL
} /* end sentinel */
90 }; /* obj_pseudo_table */
97 * Crawl along a fixS chain. Emit the segment's relocations.
99 void obj_emit_relocations(where
, fixP
, segment_address_in_file
)
101 fixS
*fixP
; /* Fixup chain for this segment. */
102 relax_addressT segment_address_in_file
;
104 for (; fixP
; fixP
= fixP
->fx_next
) {
105 if (fixP
->fx_addsy
!= NULL
) {
106 tc_bout_fix_to_chars(*where
, fixP
, segment_address_in_file
);
107 *where
+= sizeof(struct relocation_info
);
108 } /* if there's a symbol */
109 } /* for each fixup */
111 } /* emit_relocations() */
113 /* Aout file generation & utilities */
115 /* Convert a lvalue to machine dependent data */
116 void obj_header_append(where
, headers
)
118 object_headers
*headers
;
120 /* Always leave in host byte order */
122 headers
->header
.a_talign
= section_alignment
[SEG_TEXT
];
124 if (headers
->header
.a_talign
< 2){
125 headers
->header
.a_talign
= 2;
126 } /* force to at least 2 */
128 headers
->header
.a_dalign
= section_alignment
[SEG_DATA
];
129 headers
->header
.a_balign
= section_alignment
[SEG_BSS
];
131 headers
->header
.a_tload
= 0;
132 headers
->header
.a_dload
= md_section_align(SEG_DATA
, H_GET_TEXT_SIZE(headers
));
134 append(where
, (char *) &headers
->header
, sizeof(headers
->header
));
135 } /* a_header_append() */
137 void obj_symbol_to_chars(where
, symbolP
)
141 /* leave in host byte order */
142 append(where
, (char *)&symbolP
->sy_symbol
, sizeof(obj_symbol_type
));
143 } /* obj_symbol_to_chars() */
145 void obj_emit_symbols(where
, symbol_rootP
)
147 symbolS
*symbol_rootP
;
152 * Emit all symbols left in the symbol chain.
154 for(symbolP
= symbol_rootP
; symbolP
; symbolP
= symbol_next(symbolP
)) {
155 /* Used to save the offset of the name. It is used to point
156 to the string in memory but must be a file offset. */
159 temp
= S_GET_NAME(symbolP
);
160 S_SET_OFFSET(symbolP
, symbolP
->sy_name_offset
);
162 /* Any symbol still undefined and is not a dbg symbol is made N_EXT. */
163 if (!S_IS_DEBUG(symbolP
) && !S_IS_DEFINED(symbolP
)) S_SET_EXTERNAL(symbolP
);
165 obj_symbol_to_chars(where
, symbolP
);
166 S_SET_NAME(symbolP
,temp
);
168 } /* emit_symbols() */
170 void obj_symbol_new_hook(symbolP
)
173 S_SET_OTHER(symbolP
, 0);
174 S_SET_DESC(symbolP
, 0);
176 } /* obj_symbol_new_hook() */
178 static void obj_bout_line() {
179 /* Assume delimiter is part of expression. */
180 /* BSD4.2 as fails with delightful bug, so we */
181 /* are not being incompatible here. */
182 new_logical_line ((char *)NULL
, (int)(get_absolute_expression ()));
183 demand_empty_rest_of_line();
184 } /* obj_bout_line() */
189 * Handle .stabX directives, which used to be open-coded.
190 * So much creeping featurism overloaded the semantics that we decided
191 * to put all .stabX thinking in one place. Here.
193 * We try to make any .stabX directive legal. Other people's AS will often
194 * do assembly-time consistency checks: eg assigning meaning to n_type bits
195 * and "protecting" you from setting them to certain values. (They also zero
196 * certain bits before emitting symbols. Tut tut.)
198 * If an expression is not absolute we either gripe or use the relocation
199 * information. Other people's assemblers silently forget information they
200 * don't need and invent information they need that you didn't supply.
202 * .stabX directives always make a symbol table entry. It may be junk if
203 * the rest of your .stabX directive is malformed.
205 static void obj_bout_stab(what
)
208 register symbolS
* symbolP
= 0;
209 register char * string
;
212 int goof
; /* TRUE if we have aborted. */
216 * Enter with input_line_pointer pointing past .stabX and any following
219 goof
= 0; /* JF who forgot this?? */
221 string
= demand_copy_C_string(& length
);
223 if (*input_line_pointer
== ',')
224 input_line_pointer
++;
226 as_bad("I need a comma after symbol's name");
233 * Input_line_pointer->after ','. String->symbol name.
236 symbolP
= symbol_new(string
,
242 S_SET_NAME(symbolP
,NULL
); /* .stabd feature. */
243 S_SET_VALUE(symbolP
,obstack_next_free(&frags
) -
244 frag_now
->fr_literal
);
245 symbolP
->sy_frag
= frag_now
;
249 symbolP
->sy_frag
= &zero_address_frag
;
253 symbolP
->sy_frag
= & zero_address_frag
;
260 if (get_absolute_expression_and_terminator(& longint
) == ',')
261 symbolP
->sy_symbol
.n_type
= saved_type
= longint
;
263 as_bad("I want a comma after the n_type expression");
265 input_line_pointer
--; /* Backup over a non-',' char. */
269 if (get_absolute_expression_and_terminator (& longint
) == ',')
270 S_SET_OTHER(symbolP
,longint
);
272 as_bad("I want a comma after the n_other expression");
274 input_line_pointer
--; /* Backup over a non-',' char. */
278 S_SET_DESC(symbolP
, get_absolute_expression ());
279 if (what
== 's' || what
== 'n') {
280 if (* input_line_pointer
!= ',') {
281 as_bad("I want a comma after the n_desc expression");
284 input_line_pointer
++;
288 if ((! goof
) && (what
=='s' || what
=='n')) {
290 symbolP
->sy_symbol
.n_type
= saved_type
;
296 if (listing
&& !goof
)
298 if (symbolP
->sy_symbol
.n_type
== N_SLINE
)
301 listing_source_line(symbolP
->sy_symbol
.n_desc
);
303 else if (symbolP
->sy_symbol
.n_type
== N_SO
304 || symbolP
->sy_symbol
.n_type
== N_SOL
)
306 listing_source_file(string
);
314 ignore_rest_of_line ();
316 demand_empty_rest_of_line ();
317 } /* obj_bout_stab() */
319 static void obj_bout_desc() {
323 register symbolS
* symbolP
;
327 * Frob invented at RMS' request. Set the n_desc of a symbol.
329 name
= input_line_pointer
;
330 c
= get_symbol_end();
331 p
= input_line_pointer
;
334 if (*input_line_pointer
!= ',') {
336 as_bad("Expected comma after name \"%s\"", name
);
338 ignore_rest_of_line();
340 input_line_pointer
++;
341 temp
= get_absolute_expression ();
343 symbolP
= symbol_find_or_make(name
);
345 S_SET_DESC(symbolP
,temp
);
347 demand_empty_rest_of_line();
348 } /* obj_bout_desc() */
350 void obj_read_begin_hook() {
352 } /* obj_read_begin_hook() */
354 void obj_crawl_symbol_chain(headers
)
355 object_headers
*headers
;
359 int symbol_number
= 0;
361 /* JF deal with forward references first... */
362 for (symbolP
= symbol_rootP
; symbolP
; symbolP
= symbol_next(symbolP
)) {
363 if (symbolP
->sy_forward
) {
364 S_SET_VALUE(symbolP
, S_GET_VALUE(symbolP
)
365 + S_GET_VALUE(symbolP
->sy_forward
)
366 + symbolP
->sy_forward
->sy_frag
->fr_address
);
368 symbolP
->sy_forward
=0;
369 } /* if it has a forward reference */
370 } /* walk the symbol chain */
372 tc_crawl_symbol_chain(headers
);
374 symbolPP
= & symbol_rootP
; /*->last symbol chain link. */
375 while ((symbolP
= *symbolPP
) != NULL
) {
376 if (flagseen
['R'] && (S_GET_SEGMENT(symbolP
) == SEG_DATA
)) {
377 S_SET_SEGMENT(symbolP
, SEG_TEXT
);
378 } /* if pusing data into text */
380 S_SET_VALUE(symbolP
, S_GET_VALUE(symbolP
) + symbolP
->sy_frag
->fr_address
);
382 /* OK, here is how we decide which symbols go out into the
383 brave new symtab. Symbols that do are:
385 * symbols with no name (stabd's?)
386 * symbols with debug info in their N_TYPE
388 Symbols that don't are:
389 * symbols that are registers
390 * symbols with \1 as their 3rd character (numeric labels)
391 * "local labels" as defined by S_LOCAL_NAME(name)
392 if the -L switch was passed to gas.
394 All other symbols are output. We complain if a deleted
395 symbol was marked external. */
399 && !S_IS_REGISTER(symbolP
)
400 && (!S_GET_NAME(symbolP
)
401 || S_IS_DEBUG(symbolP
)
403 /* FIXME-SOON this ifdef seems highly dubious to me. xoxorich. */
404 || !S_IS_DEFINED(symbolP
)
405 || S_IS_EXTERNAL(symbolP
)
407 || (S_GET_NAME(symbolP
)[0] != '\001' && (flagseen
['L'] || ! S_LOCAL_NAME(symbolP
))))) {
408 symbolP
->sy_number
= symbol_number
++;
410 /* The + 1 after strlen account for the \0 at the
411 end of each string */
412 if (!S_IS_STABD(symbolP
)) {
414 symbolP
->sy_name_offset
= string_byte_count
;
415 string_byte_count
+= strlen(S_GET_NAME(symbolP
)) + 1;
417 else /* .Stabd case. */
418 symbolP
->sy_name_offset
= 0;
419 symbolPP
= &(symbol_next(symbolP
));
421 if (S_IS_EXTERNAL(symbolP
) || !S_IS_DEFINED(symbolP
)) {
422 as_bad("Local symbol %s never defined", S_GET_NAME(symbolP
));
425 /* Unhook it from the chain */
426 *symbolPP
= symbol_next(symbolP
);
427 } /* if this symbol should be in the output */
428 } /* for each symbol */
430 H_SET_SYMBOL_TABLE_SIZE(headers
, symbol_number
);
433 } /* obj_crawl_symbol_chain() */
436 * Find strings by crawling along symbol table chain.
439 void obj_emit_strings(where
)
445 /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */
446 md_number_to_chars(*where
, string_byte_count
, sizeof(string_byte_count
));
447 *where
+= sizeof(string_byte_count
);
448 #else /* CROSS_COMPILE */
449 append(where
, (char *) &string_byte_count
, (unsigned long) sizeof(string_byte_count
));
450 #endif /* CROSS_COMPILE */
452 for(symbolP
= symbol_rootP
; symbolP
; symbolP
= symbol_next(symbolP
)) {
453 if(S_GET_NAME(symbolP
))
454 append(where
, S_GET_NAME(symbolP
), (unsigned long)(strlen (S_GET_NAME(symbolP
)) + 1));
455 } /* walk symbol chain */
458 } /* obj_emit_strings() */
467 /* end of obj-bout.c */