White space and comment changes. #ifdef __STDC__ becomes #if __STDC__
[deliverable/binutils-gdb.git] / gas / write.c
1 /* write.c - emit .o file
2
3 Copyright (C) 1986, 1987, 1990, 1991, 1992 Free Software Foundation, Inc.
4
5 This file is part of GAS, the GNU Assembler.
6
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to
19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
20
21 /*
22
23 This thing should be set up to do byteordering correctly. But...
24
25 In order to cross-assemble the target machine must have an a.out header
26 similar to the one in a.out.h on THIS machine. Byteorder doesn't matter,
27 we take special care of it, but the numbers must be the same SIZE (# of
28 bytes) and in the same PLACE. If this is not true, you will have some
29 trouble.
30 */
31
32 #include "as.h"
33 #include "subsegs.h"
34 #include "obstack.h"
35 #include "output-file.h"
36
37 #ifndef MANY_SEGMENTS
38 static struct frag *text_frag_root;
39 static struct frag *data_frag_root;
40
41 static struct frag *text_last_frag; /* Last frag in segment. */
42 static struct frag *data_last_frag; /* Last frag in segment. */
43 #endif
44
45 static object_headers headers;
46
47 long string_byte_count;
48
49 static char *the_object_file;
50
51 char *next_object_file_charP; /* Tracks object file bytes. */
52
53 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
54
55 /* static long length; JF unused */ /* String length, including trailing '\0'. */
56
57
58 #if __STDC__ == 1
59
60 static int is_dnrange(struct frag *f1, struct frag *f2);
61 static long fixup_segment(fixS *fixP, segT this_segment_type);
62 static relax_addressT relax_align(relax_addressT address, long alignment);
63 void relax_segment(struct frag *segment_frag_root, segT segment_type);
64
65 #else
66
67 static int is_dnrange();
68 static long fixup_segment();
69 static relax_addressT relax_align();
70 void relax_segment();
71
72 #endif /* not __STDC__ */
73
74 /*
75 * fix_new()
76 *
77 * Create a fixS in obstack 'notes'.
78 */
79 fixS *fix_new(frag, where, size, add_symbol, sub_symbol, offset, pcrel, r_type)
80 fragS *frag; /* Which frag? */
81 int where; /* Where in that frag? */
82 short int size; /* 1, 2 or 4 usually. */
83 symbolS *add_symbol; /* X_add_symbol. */
84 symbolS *sub_symbol; /* X_subtract_symbol. */
85 long offset; /* X_add_number. */
86 int pcrel; /* TRUE if PC-relative relocation. */
87 enum reloc_type r_type; /* Relocation type */
88 {
89 register fixS * fixP;
90
91 fixP = (fixS *)obstack_alloc(&notes,sizeof(fixS));
92
93 fixP->fx_frag = frag;
94 fixP->fx_where = where;
95 fixP->fx_size = size;
96 fixP->fx_addsy = add_symbol;
97 fixP->fx_subsy = sub_symbol;
98 fixP->fx_offset = offset;
99 fixP->fx_pcrel = pcrel;
100 fixP->fx_r_type = r_type;
101
102 /* JF these 'cuz of the NS32K stuff */
103 fixP->fx_im_disp = 0;
104 fixP->fx_pcrel_adjust = 0;
105 fixP->fx_bsr = 0;
106 fixP->fx_bit_fixP = 0;
107
108 /* usually, we want relocs sorted numerically, but while
109 comparing to older versions of gas that have relocs
110 reverse sorted, it is convenient to have this compile
111 time option. xoxorich. */
112
113 #ifdef REVERSE_SORT_RELOCS
114
115 fixP->fx_next = *seg_fix_rootP;
116 *seg_fix_rootP = fixP;
117
118 #else /* REVERSE_SORT_RELOCS */
119
120 fixP->fx_next = NULL;
121
122 if (*seg_fix_tailP)
123 (*seg_fix_tailP)->fx_next = fixP;
124 else
125 *seg_fix_rootP = fixP;
126 *seg_fix_tailP = fixP;
127
128 #endif /* REVERSE_SORT_RELOCS */
129
130 fixP->fx_callj = 0;
131 return fixP;
132 }
133 #ifndef BFD
134 void write_object_file()
135 {
136 register struct frchain * frchainP; /* Track along all frchains. */
137 register fragS * fragP; /* Track along all frags. */
138 register struct frchain * next_frchainP;
139 register fragS * * prev_fragPP;
140 /* register char * name; */
141 /* symbolS *symbolP; */
142 /* register symbolS ** symbolPP; */
143 /* register fixS * fixP; JF unused */
144 unsigned int data_siz;
145
146 #ifdef DONTDEF
147 void gdb_emit();
148 void gdb_end();
149 #endif
150 long object_file_size;
151
152 #ifdef VMS
153 /*
154 * Under VMS we try to be compatible with VAX-11 "C". Thus, we
155 * call a routine to check for the definition of the procedure
156 * "_main", and if so -- fix it up so that it can be program
157 * entry point.
158 */
159 VMS_Check_For_Main();
160 #endif /* VMS */
161 /*
162 * After every sub-segment, we fake an ".align ...". This conforms to BSD4.2
163 * brane-damage. We then fake ".fill 0" because that is the kind of frag
164 * that requires least thought. ".align" frags like to have a following
165 * frag since that makes calculating their intended length trivial.
166 */
167 #define SUB_SEGMENT_ALIGN (2)
168 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next) {
169 #ifdef VMS
170 /*
171 * Under VAX/VMS, the linker (and PSECT specifications)
172 * take care of correctly aligning the segments.
173 * Doing the alignment here (on initialized data) can
174 * mess up the calculation of global data PSECT sizes.
175 */
176 #undef SUB_SEGMENT_ALIGN
177 #define SUB_SEGMENT_ALIGN ((frchainP->frch_seg != SEG_DATA) ? 2 : 0)
178 #endif /* VMS */
179 subseg_new (frchainP->frch_seg, frchainP->frch_subseg);
180 frag_align (SUB_SEGMENT_ALIGN, 0);
181 /* frag_align will have left a new frag. */
182 /* Use this last frag for an empty ".fill". */
183 /*
184 * For this segment ...
185 * Create a last frag. Do not leave a "being filled in frag".
186 */
187 frag_wane (frag_now);
188 frag_now->fr_fix = 0;
189 know( frag_now->fr_next == NULL );
190 /* know( frags . obstack_c_base == frags . obstack_c_next_free ); */
191 /* Above shows we haven't left a half-completed object on obstack. */
192 } /* walk the frag chain */
193
194 /*
195 * From now on, we don't care about sub-segments.
196 * Build one frag chain for each segment. Linked thru fr_next.
197 * We know that there is at least 1 text frchain & at least 1 data frchain.
198 */
199 prev_fragPP = &text_frag_root;
200 for (frchainP = frchain_root; frchainP; frchainP = next_frchainP) {
201 know( frchainP->frch_root );
202 * prev_fragPP = frchainP->frch_root;
203 prev_fragPP = & frchainP->frch_last->fr_next;
204
205 if (((next_frchainP = frchainP->frch_next) == NULL)
206 || next_frchainP == data0_frchainP) {
207 prev_fragPP = & data_frag_root;
208 if (next_frchainP) {
209 text_last_frag = frchainP->frch_last;
210 } else {
211 data_last_frag = frchainP->frch_last;
212 }
213 }
214 } /* walk the frag chain */
215
216 /*
217 * We have two segments. If user gave -R flag, then we must put the
218 * data frags into the text segment. Do this before relaxing so
219 * we know to take advantage of -R and make shorter addresses.
220 */
221 if (flagseen[ 'R' ]) {
222 fixS *tmp;
223
224 text_last_frag->fr_next = data_frag_root;
225 text_last_frag = data_last_frag;
226 data_last_frag = NULL;
227 data_frag_root = NULL;
228 if (text_fix_root) {
229 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next) ;;
230 tmp->fx_next=data_fix_root;
231 } else
232 text_fix_root=data_fix_root;
233 data_fix_root=NULL;
234 }
235
236 relax_segment(text_frag_root, SEG_TEXT);
237 relax_segment(data_frag_root, SEG_DATA);
238 /*
239 * Now the addresses of frags are correct within the segment.
240 */
241
242 know(text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
243 H_SET_TEXT_SIZE(&headers, text_last_frag->fr_address);
244 text_last_frag->fr_address = H_GET_TEXT_SIZE(&headers);
245
246 /*
247 * Join the 2 segments into 1 huge segment.
248 * To do this, re-compute every rn_address in the SEG_DATA frags.
249 * Then join the data frags after the text frags.
250 *
251 * Determine a_data [length of data segment].
252 */
253 if (data_frag_root) {
254 register relax_addressT slide;
255
256 know((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
257
258 H_SET_DATA_SIZE(&headers, data_last_frag->fr_address);
259 data_last_frag->fr_address = H_GET_DATA_SIZE(&headers);
260 slide = H_GET_TEXT_SIZE(&headers); /* & in file of the data segment. */
261
262 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next) {
263 fragP->fr_address += slide;
264 } /* for each data frag */
265
266 know(text_last_frag != 0);
267 text_last_frag->fr_next = data_frag_root;
268 } else {
269 H_SET_DATA_SIZE(&headers,0);
270 data_siz = 0;
271 }
272
273 bss_address_frag.fr_address = H_GET_TEXT_SIZE(&headers) +
274 H_GET_DATA_SIZE(&headers);
275
276 H_SET_BSS_SIZE(&headers,local_bss_counter);
277
278 /*
279 *
280 * Crawl the symbol chain.
281 *
282 * For each symbol whose value depends on a frag, take the address of
283 * that frag and subsume it into the value of the symbol.
284 * After this, there is just one way to lookup a symbol value.
285 * Values are left in their final state for object file emission.
286 * We adjust the values of 'L' local symbols, even if we do
287 * not intend to emit them to the object file, because their values
288 * are needed for fix-ups.
289 *
290 * Unless we saw a -L flag, remove all symbols that begin with 'L'
291 * from the symbol chain. (They are still pointed to by the fixes.)
292 *
293 * Count the remaining symbols.
294 * Assign a symbol number to each symbol.
295 * Count the number of string-table chars we will emit.
296 * Put this info into the headers as appropriate.
297 *
298 */
299 know(zero_address_frag.fr_address == 0);
300 string_byte_count = sizeof(string_byte_count);
301
302 obj_crawl_symbol_chain(&headers);
303
304 if (string_byte_count == sizeof(string_byte_count)) {
305 string_byte_count = 0;
306 } /* if no strings, then no count. */
307
308 H_SET_STRING_SIZE(&headers, string_byte_count);
309
310 /*
311 * Addresses of frags now reflect addresses we use in the object file.
312 * Symbol values are correct.
313 * Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
314 * Also converting any machine-dependent frags using md_convert_frag();
315 */
316 subseg_change(SEG_TEXT, 0);
317
318 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next) {
319 switch (fragP->fr_type) {
320 case rs_align:
321 case rs_org:
322 fragP->fr_type = rs_fill;
323 know(fragP->fr_var == 1);
324 know(fragP->fr_next != NULL);
325
326 fragP->fr_offset = (fragP->fr_next->fr_address
327 - fragP->fr_address
328 - fragP->fr_fix);
329 break;
330
331 case rs_fill:
332 break;
333
334 case rs_machine_dependent:
335 md_convert_frag(&headers, fragP);
336
337 know((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == fragP->fr_fix));
338
339 /*
340 * After md_convert_frag, we make the frag into a ".space 0".
341 * Md_convert_frag() should set up any fixSs and constants
342 * required.
343 */
344 frag_wane(fragP);
345 break;
346
347 #ifndef WORKING_DOT_WORD
348 case rs_broken_word: {
349 struct broken_word *lie;
350 extern md_short_jump_size;
351 extern md_long_jump_size;
352
353 if (fragP->fr_subtype) {
354 fragP->fr_fix+=md_short_jump_size;
355 for (lie=(struct broken_word *)(fragP->fr_symbol);lie && lie->dispfrag==fragP;lie=lie->next_broken_word)
356 if (lie->added==1)
357 fragP->fr_fix+=md_long_jump_size;
358 }
359 frag_wane(fragP);
360 }
361 break;
362 #endif
363
364 default:
365 BAD_CASE( fragP->fr_type );
366 break;
367 } /* switch (fr_type) */
368
369 know((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == (fragP->fr_fix + (fragP->fr_offset * fragP->fr_var))));
370 } /* for each frag. */
371
372 #ifndef WORKING_DOT_WORD
373 {
374 struct broken_word *lie;
375 struct broken_word **prevP;
376
377 prevP= &broken_words;
378 for (lie=broken_words; lie; lie=lie->next_broken_word)
379 if (!lie->added) {
380 #ifdef TC_NS32K
381 fix_new_ns32k(lie->frag,
382 lie->word_goes_here - lie->frag->fr_literal,
383 2,
384 lie->add,
385 lie->sub,
386 lie->addnum,
387 0, 0, 2, 0, 0);
388 #else /* TC_NS32K */
389 fix_new( lie->frag, lie->word_goes_here - lie->frag->fr_literal,
390 2, lie->add,
391 lie->sub, lie->addnum,
392 0, NO_RELOC);
393 #endif /* TC_NS32K */
394 /* md_number_to_chars(lie->word_goes_here,
395 S_GET_VALUE(lie->add)
396 + lie->addnum
397 - S_GET_VALUE(lie->sub),
398 2); */
399 *prevP=lie->next_broken_word;
400 } else
401 prevP= &(lie->next_broken_word);
402
403 for (lie=broken_words;lie;) {
404 struct broken_word *untruth;
405 char *table_ptr;
406 long table_addr;
407 long from_addr,
408 to_addr;
409 int n,
410 m;
411
412 extern md_short_jump_size;
413 extern md_long_jump_size;
414
415 fragP=lie->dispfrag;
416
417 /* Find out how many broken_words go here */
418 n=0;
419 for (untruth=lie;untruth && untruth->dispfrag==fragP;untruth=untruth->next_broken_word)
420 if (untruth->added==1)
421 n++;
422
423 table_ptr=lie->dispfrag->fr_opcode;
424 table_addr=lie->dispfrag->fr_address+(table_ptr - lie->dispfrag->fr_literal);
425 /* Create the jump around the long jumps */
426 /* This is a short jump from table_ptr+0 to table_ptr+n*long_jump_size */
427 from_addr=table_addr;
428 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
429 md_create_short_jump(table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
430 table_ptr+=md_short_jump_size;
431 table_addr+=md_short_jump_size;
432
433 for (m=0;lie && lie->dispfrag==fragP;m++,lie=lie->next_broken_word) {
434 if (lie->added==2)
435 continue;
436 /* Patch the jump table */
437 /* This is the offset from ??? to table_ptr+0 */
438 to_addr = table_addr
439 - S_GET_VALUE(lie->sub);
440 md_number_to_chars(lie->word_goes_here,to_addr,2);
441 for (untruth=lie->next_broken_word;untruth && untruth->dispfrag==fragP;untruth=untruth->next_broken_word) {
442 if (untruth->use_jump==lie)
443 md_number_to_chars(untruth->word_goes_here,to_addr,2);
444 }
445
446 /* Install the long jump */
447 /* this is a long jump from table_ptr+0 to the final target */
448 from_addr=table_addr;
449 to_addr=S_GET_VALUE(lie->add) + lie->addnum;
450 md_create_long_jump(table_ptr,from_addr,to_addr,lie->dispfrag,lie->add);
451 table_ptr+=md_long_jump_size;
452 table_addr+=md_long_jump_size;
453 }
454 }
455 }
456 #endif /* not WORKING_DOT_WORD */
457
458 #ifndef VMS
459 { /* not vms */
460 /*
461 * Scan every FixS performing fixups. We had to wait until now to do
462 * this because md_convert_frag() may have made some fixSs.
463 */
464
465 H_SET_RELOCATION_SIZE(&headers,
466 md_reloc_size * fixup_segment(text_fix_root, SEG_TEXT),
467 md_reloc_size * fixup_segment(data_fix_root, SEG_DATA));
468
469
470 /* FIXME move this stuff into the pre-write-hook */
471 H_SET_MAGIC_NUMBER(&headers, magic_number_for_object_file);
472 H_SET_ENTRY_POINT(&headers, 0);
473
474 obj_pre_write_hook(&headers); /* extra coff stuff */
475 if ((had_warnings() && flagseen['Z'])
476 || had_errors() > 0) {
477 if (flagseen['Z']) {
478 as_warn("%d error%s, %d warning%s, generating bad object file.\n",
479 had_errors(), had_errors() == 1 ? "" : "s",
480 had_warnings(), had_warnings() == 1 ? "" : "s");
481 } else {
482 as_fatal("%d error%s, %d warning%s, no object file generated.\n",
483 had_errors(), had_errors() == 1 ? "" : "s",
484 had_warnings(), had_warnings() == 1 ? "" : "s");
485 } /* on want output */
486 } /* on error condition */
487
488 object_file_size = H_GET_FILE_SIZE(&headers);
489 next_object_file_charP = the_object_file = xmalloc(object_file_size);
490
491 output_file_create(out_file_name);
492
493 obj_header_append(&next_object_file_charP, &headers);
494
495 know((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE(&headers));
496
497 /*
498 * Emit code.
499 */
500 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next) {
501 register long count;
502 register char *fill_literal;
503 register long fill_size;
504
505 know(fragP->fr_type == rs_fill);
506 append(&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
507 fill_literal = fragP->fr_literal + fragP->fr_fix;
508 fill_size = fragP->fr_var;
509 know(fragP->fr_offset >= 0);
510
511 for (count = fragP->fr_offset; count; count--) {
512 append(&next_object_file_charP, fill_literal, (unsigned long) fill_size);
513 } /* for each */
514
515 } /* for each code frag. */
516
517 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers)));
518
519 /*
520 * Emit relocations.
521 */
522 obj_emit_relocations(&next_object_file_charP, text_fix_root, (relax_addressT)0);
523 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers)));
524 #ifdef TC_I960
525 /* Make addresses in data relocation directives relative to beginning of
526 * first data fragment, not end of last text fragment: alignment of the
527 * start of the data segment may place a gap between the segments.
528 */
529 obj_emit_relocations(&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
530 #else /* TC_I960 */
531 obj_emit_relocations(&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
532 #endif /* TC_I960 */
533
534 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers) + H_GET_DATA_RELOCATION_SIZE(&headers)));
535
536 /*
537 * Emit line number entries.
538 */
539 OBJ_EMIT_LINENO(&next_object_file_charP, lineno_rootP, the_object_file);
540 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers) + H_GET_DATA_RELOCATION_SIZE(&headers) + H_GET_LINENO_SIZE(&headers)));
541
542 /*
543 * Emit symbols.
544 */
545 obj_emit_symbols(&next_object_file_charP, symbol_rootP);
546 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers) + H_GET_DATA_RELOCATION_SIZE(&headers) + H_GET_LINENO_SIZE(&headers) + H_GET_SYMBOL_TABLE_SIZE(&headers)));
547
548 /*
549 * Emit strings.
550 */
551
552 if (string_byte_count > 0) {
553 obj_emit_strings(&next_object_file_charP);
554 } /* only if we have a string table */
555
556 /* know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers) + H_GET_DATA_RELOCATION_SIZE(&headers) + H_GET_LINENO_SIZE(&headers) + H_GET_SYMBOL_TABLE_SIZE(&headers) + H_GET_STRING_SIZE(&headers)));
557 */
558 /* know(next_object_file_charP == the_object_file + object_file_size);*/
559
560 #ifdef BFD_HEADERS
561 bfd_seek(stdoutput, 0, 0);
562 bfd_write(the_object_file, 1, object_file_size, stdoutput);
563 #else
564
565 /* Write the data to the file */
566 output_file_append(the_object_file,object_file_size,out_file_name);
567 #endif
568
569 #ifdef DONTDEF
570 if (flagseen['G']) /* GDB symbol file to be appended? */
571 {
572 gdb_emit (out_file_name);
573 gdb_end ();
574 }
575 #endif /* DONTDEF */
576
577 output_file_close(out_file_name);
578 } /* non vms output */
579 #else /* VMS */
580 /*
581 * Now do the VMS-dependent part of writing the object file
582 */
583 VMS_write_object_file(text_siz, data_siz, text_frag_root, data_frag_root);
584 #endif /* VMS */
585 } /* write_object_file() */
586 #else
587 #endif
588
589 /*
590 * relax_segment()
591 *
592 * Now we have a segment, not a crowd of sub-segments, we can make fr_address
593 * values.
594 *
595 * Relax the frags.
596 *
597 * After this, all frags in this segment have addresses that are correct
598 * within the segment. Since segments live in different file addresses,
599 * these frag addresses may not be the same as final object-file addresses.
600 */
601
602
603
604 void relax_segment(segment_frag_root, segment)
605 struct frag * segment_frag_root;
606 segT segment; /* SEG_DATA or SEG_TEXT */
607 {
608 register struct frag * fragP;
609 register relax_addressT address;
610 /* register relax_addressT old_address; JF unused */
611 /* register relax_addressT new_address; JF unused */
612 #ifndef MANY_SEGMENTS
613 know( segment == SEG_DATA || segment == SEG_TEXT );
614 #endif
615 /* In case md_estimate_size_before_relax() wants to make fixSs. */
616 subseg_change(segment, 0);
617
618 /*
619 * For each frag in segment: count and store (a 1st guess of) fr_address.
620 */
621 address = 0;
622 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) {
623 fragP->fr_address = address;
624 address += fragP->fr_fix;
625
626 switch (fragP->fr_type) {
627 case rs_fill:
628 address += fragP->fr_offset * fragP->fr_var ;
629 break;
630
631 case rs_align:
632 address += relax_align(address, fragP->fr_offset);
633 break;
634
635 case rs_org:
636 /*
637 * Assume .org is nugatory. It will grow with 1st relax.
638 */
639 break;
640
641 case rs_machine_dependent:
642 address += md_estimate_size_before_relax(fragP, segment);
643 break;
644
645 #ifndef WORKING_DOT_WORD
646 /* Broken words don't concern us yet */
647 case rs_broken_word:
648 break;
649 #endif
650
651 default:
652 BAD_CASE(fragP->fr_type);
653 break;
654 } /* switch(fr_type) */
655 } /* for each frag in the segment */
656
657 /*
658 * Do relax().
659 */
660 {
661 register long stretch; /* May be any size, 0 or negative. */
662 /* Cumulative number of addresses we have */
663 /* relaxed this pass. */
664 /* We may have relaxed more than one address. */
665 register long stretched; /* Have we stretched on this pass? */
666 /* This is 'cuz stretch may be zero, when,
667 in fact some piece of code grew, and
668 another shrank. If a branch instruction
669 doesn't fit anymore, we could be scrod */
670
671 do {
672 stretch = stretched = 0;
673 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) {
674 register long growth = 0;
675 register unsigned long was_address;
676 /* register long var; */
677 register long offset;
678 register symbolS *symbolP;
679 register long target;
680 register long after;
681 register long aim;
682
683 was_address = fragP->fr_address;
684 address = fragP->fr_address += stretch;
685 symbolP = fragP->fr_symbol;
686 offset = fragP->fr_offset;
687 /* var = fragP->fr_var; */
688
689 switch (fragP->fr_type) {
690 case rs_fill: /* .fill never relaxes. */
691 growth = 0;
692 break;
693
694 #ifndef WORKING_DOT_WORD
695 /* JF: This is RMS's idea. I do *NOT* want to be blamed
696 for it I do not want to write it. I do not want to have
697 anything to do with it. This is not the proper way to
698 implement this misfeature. */
699 case rs_broken_word: {
700 struct broken_word *lie;
701 struct broken_word *untruth;
702 extern int md_short_jump_size;
703 extern int md_long_jump_size;
704
705 /* Yes this is ugly (storing the broken_word pointer
706 in the symbol slot). Still, this whole chunk of
707 code is ugly, and I don't feel like doing anything
708 about it. Think of it as stubbornness in action */
709 growth=0;
710 for (lie=(struct broken_word *)(fragP->fr_symbol);
711 lie && lie->dispfrag==fragP;
712 lie=lie->next_broken_word) {
713
714 if (lie->added)
715 continue;
716
717 offset= lie->add->sy_frag->fr_address+ S_GET_VALUE(lie->add) + lie->addnum -
718 (lie->sub->sy_frag->fr_address+ S_GET_VALUE(lie->sub));
719 if (offset<=-32768 || offset>=32767) {
720 if (flagseen['k'])
721 as_warn(".word %s-%s+%ld didn't fit",
722 S_GET_NAME(lie->add),
723 S_GET_NAME(lie->sub),
724 lie->addnum);
725 lie->added=1;
726 if (fragP->fr_subtype==0) {
727 fragP->fr_subtype++;
728 growth+=md_short_jump_size;
729 }
730 for (untruth=lie->next_broken_word;untruth && untruth->dispfrag==lie->dispfrag;untruth=untruth->next_broken_word)
731 if ((untruth->add->sy_frag == lie->add->sy_frag)
732 && S_GET_VALUE(untruth->add) == S_GET_VALUE(lie->add)) {
733 untruth->added=2;
734 untruth->use_jump=lie;
735 }
736 growth+=md_long_jump_size;
737 }
738 }
739
740 break;
741 } /* case rs_broken_word */
742 #endif
743 case rs_align:
744 growth = relax_align((relax_addressT) (address + fragP->fr_fix), offset)
745 - relax_align((relax_addressT) (was_address + fragP->fr_fix), offset);
746 break;
747
748 case rs_org:
749 target = offset;
750
751 if (symbolP) {
752 #ifdef MANY_SEGMENTS
753 #else
754 know((S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || (S_GET_SEGMENT(symbolP) == SEG_DATA) || (S_GET_SEGMENT(symbolP) == SEG_TEXT));
755 know(symbolP->sy_frag);
756 know(!(S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || (symbolP->sy_frag == &zero_address_frag));
757 #endif
758 target += S_GET_VALUE(symbolP)
759 + symbolP->sy_frag->fr_address;
760 } /* if we have a symbol */
761
762 know(fragP->fr_next);
763 after = fragP->fr_next->fr_address;
764 growth = ((target - after ) > 0) ? (target - after) : 0;
765 /* Growth may be -ve, but variable part */
766 /* of frag cannot have < 0 chars. */
767 /* That is, we can't .org backwards. */
768
769 growth -= stretch; /* This is an absolute growth factor */
770 break;
771
772 case rs_machine_dependent: {
773 register const relax_typeS * this_type;
774 register const relax_typeS * start_type;
775 register relax_substateT next_state;
776 register relax_substateT this_state;
777
778 start_type = this_type = md_relax_table + (this_state = fragP->fr_subtype);
779 target = offset;
780
781 if (symbolP) {
782 #ifndef MANY_SEGMENTS
783 know((S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || (S_GET_SEGMENT(symbolP) == SEG_DATA) || (S_GET_SEGMENT(symbolP) == SEG_TEXT));
784 #endif
785 know(symbolP->sy_frag);
786 know(!(S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || symbolP->sy_frag==&zero_address_frag );
787 target +=
788 S_GET_VALUE(symbolP)
789 + symbolP->sy_frag->fr_address;
790
791 /* If frag has yet to be reached on this pass,
792 assume it will move by STRETCH just as we did.
793 If this is not so, it will be because some frag
794 between grows, and that will force another pass. */
795
796 /* JF was just address */
797 /* JF also added is_dnrange hack */
798 /* There's gotta be a better/faster/etc way
799 to do this. . . */
800 /* gnu@cygnus.com: I changed this from > to >=
801 because I ran into a zero-length frag (fr_fix=0)
802 which was created when the obstack needed a new
803 chunk JUST AFTER the opcode of a branch. Since
804 fr_fix is zero, fr_address of this frag is the same
805 as fr_address of the next frag. This
806 zero-length frag was variable and jumped to .+2
807 (in the next frag), but since the > comparison
808 below failed (the two were =, not >), "stretch"
809 was not added to the target. Stretch was 178, so
810 the offset appeared to be .-176 instead, which did
811 not fit into a byte branch, so the assembler
812 relaxed the branch to a word. This didn't compare
813 with what happened when the same source file was
814 assembled on other machines, which is how I found it.
815 You might want to think about what other places have
816 trouble with zero length frags... */
817
818 if (symbolP->sy_frag->fr_address >= was_address
819 && is_dnrange(fragP,symbolP->sy_frag)) {
820 target += stretch;
821 } /* */
822
823 } /* if there's a symbol attached */
824
825 aim = target - address - fragP->fr_fix;
826 /* The displacement is affected by the instruction size
827 * for the 32k architecture. I think we ought to be able
828 * to add fragP->fr_pcrel_adjust in all cases (it should be
829 * zero if not used), but just in case it breaks something
830 * else we'll put this inside #ifdef NS32K ... #endif
831 */
832 #ifdef TC_NS32K
833 aim += fragP->fr_pcrel_adjust;
834 #endif /* TC_NS32K */
835
836 if (aim < 0) {
837 /* Look backwards. */
838 for (next_state = this_type->rlx_more; next_state; ) {
839 if (aim >= this_type->rlx_backward) {
840 next_state = 0;
841 } else { /* Grow to next state. */
842 this_type = md_relax_table + (this_state = next_state);
843 next_state = this_type->rlx_more;
844 }
845 }
846 } else {
847 #ifdef DONTDEF
848 /* JF these next few lines of code are for the mc68020 which can't handle short
849 offsets of zero in branch instructions. What a kludge! */
850 if (aim==0 && this_state==(1<<2+0)) { /* FOO hard encoded from m.c */
851 aim=this_type->rlx_forward+1; /* Force relaxation into word mode */
852 }
853 #endif
854 #ifdef M68K_AIM_KLUDGE
855 M68K_AIM_KLUDGE(aim, this_state, this_type);
856 #endif
857 /* JF end of 68020 code */
858 /* Look forwards. */
859 for (next_state = this_type->rlx_more; next_state; ) {
860 if (aim <= this_type->rlx_forward) {
861 next_state = 0;
862 } else { /* Grow to next state. */
863 this_type = md_relax_table + (this_state = next_state);
864 next_state = this_type->rlx_more;
865 }
866 }
867 }
868
869 if ((growth = this_type->rlx_length - start_type->rlx_length) != 0)
870 fragP->fr_subtype = this_state;
871
872 break;
873 } /* case rs_machine_dependent */
874
875 default:
876 BAD_CASE( fragP->fr_type );
877 break;
878 }
879 if (growth) {
880 stretch += growth;
881 stretched++;
882 }
883 } /* For each frag in the segment. */
884 } while (stretched); /* Until nothing further to relax. */
885 } /* do_relax */
886
887 /*
888 * We now have valid fr_address'es for each frag.
889 */
890
891 /*
892 * All fr_address's are correct, relative to their own segment.
893 * We have made all the fixS we will ever make.
894 */
895 } /* relax_segment() */
896
897 /*
898 * Relax_align. Advance location counter to next address that has 'alignment'
899 * lowest order bits all 0s.
900 */
901
902 /* How many addresses does the .align take? */
903 static relax_addressT relax_align(address, alignment)
904 register relax_addressT address; /* Address now. */
905 register long alignment; /* Alignment (binary). */
906 {
907 relax_addressT mask;
908 relax_addressT new_address;
909
910 mask = ~ ( (~0) << alignment );
911 new_address = (address + mask) & (~ mask);
912 return (new_address - address);
913 } /* relax_align() */
914
915 /* fixup_segment()
916
917 Go through all the fixS's in a segment and see which ones can be
918 handled now. (These consist of fixS where we have since discovered
919 the value of a symbol, or the address of the frag involved.)
920 For each one, call md_apply_fix to put the fix into the frag data.
921
922 Result is a count of how many relocation structs will be needed to
923 handle the remaining fixS's that we couldn't completely handle here.
924 These will be output later by emit_relocations(). */
925
926 static long fixup_segment(fixP, this_segment_type)
927 register fixS * fixP;
928 segT this_segment_type; /* N_TYPE bits for segment. */
929 {
930 register long seg_reloc_count;
931 register symbolS *add_symbolP;
932 register symbolS *sub_symbolP;
933 register long add_number;
934 register int size;
935 register char *place;
936 register long where;
937 register char pcrel;
938 register fragS *fragP;
939 register segT add_symbol_segment = SEG_ABSOLUTE;
940
941 /* FIXME: remove this line */ /* fixS *orig = fixP; */
942 seg_reloc_count = 0;
943
944 for ( ; fixP; fixP = fixP->fx_next) {
945 fragP = fixP->fx_frag;
946 know(fragP);
947 where = fixP->fx_where;
948 place = fragP->fr_literal + where;
949 size = fixP->fx_size;
950 add_symbolP = fixP->fx_addsy;
951 #ifdef TC_I960
952 if (fixP->fx_callj && TC_S_IS_CALLNAME(add_symbolP)) {
953 /* Relocation should be done via the
954 associated 'bal' entry point
955 symbol. */
956
957 if (!TC_S_IS_BALNAME(tc_get_bal_of_call(add_symbolP))) {
958 as_bad("No 'bal' entry point for leafproc %s",
959 S_GET_NAME(add_symbolP));
960 continue;
961 }
962 fixP->fx_addsy = add_symbolP = tc_get_bal_of_call(add_symbolP);
963 } /* callj relocation */
964 #endif
965 sub_symbolP = fixP->fx_subsy;
966 add_number = fixP->fx_offset;
967 pcrel = fixP->fx_pcrel;
968
969 if (add_symbolP) {
970 add_symbol_segment = S_GET_SEGMENT(add_symbolP);
971 } /* if there is an addend */
972
973 if (sub_symbolP) {
974 if (!add_symbolP) {
975 /* Its just -sym */
976 if (S_GET_SEGMENT(sub_symbolP) != SEG_ABSOLUTE) {
977 as_bad("Negative of non-absolute symbol %s", S_GET_NAME(sub_symbolP));
978 } /* not absolute */
979
980 add_number -= S_GET_VALUE(sub_symbolP);
981
982 /* if sub_symbol is in the same segment that add_symbol
983 and add_symbol is either in DATA, TEXT, BSS or ABSOLUTE */
984 } else if ((S_GET_SEGMENT(sub_symbolP) == add_symbol_segment)
985 && (SEG_NORMAL(add_symbol_segment)
986 || (add_symbol_segment == SEG_ABSOLUTE))) {
987 /* Difference of 2 symbols from same segment. */
988 /* Can't make difference of 2 undefineds: 'value' means */
989 /* something different for N_UNDF. */
990 #ifdef TC_I960
991 /* Makes no sense to use the difference of 2 arbitrary symbols
992 * as the target of a call instruction.
993 */
994 if (fixP->fx_callj) {
995 as_bad("callj to difference of 2 symbols");
996 }
997 #endif /* TC_I960 */
998 add_number += S_GET_VALUE(add_symbolP) -
999 S_GET_VALUE(sub_symbolP);
1000
1001 add_symbolP = NULL;
1002 fixP->fx_addsy = NULL;
1003 } else {
1004 /* Different segments in subtraction. */
1005 know(!(S_IS_EXTERNAL(sub_symbolP) && (S_GET_SEGMENT(sub_symbolP) == SEG_ABSOLUTE)));
1006
1007 if ((S_GET_SEGMENT(sub_symbolP) == SEG_ABSOLUTE)) {
1008 add_number -= S_GET_VALUE(sub_symbolP);
1009 } else {
1010 as_bad("Can't emit reloc {- %s-seg symbol \"%s\"} @ file address %d.",
1011 segment_name(S_GET_SEGMENT(sub_symbolP)),
1012 S_GET_NAME(sub_symbolP), fragP->fr_address + where);
1013 } /* if absolute */
1014 }
1015 } /* if sub_symbolP */
1016
1017 if (add_symbolP) {
1018 if (add_symbol_segment == this_segment_type && pcrel) {
1019 /*
1020 * This fixup was made when the symbol's segment was
1021 * SEG_UNKNOWN, but it is now in the local segment.
1022 * So we know how to do the address without relocation.
1023 */
1024 #ifdef TC_I960
1025 /* reloc_callj() may replace a 'call' with a 'calls' or a 'bal',
1026 * in which cases it modifies *fixP as appropriate. In the case
1027 * of a 'calls', no further work is required, and *fixP has been
1028 * set up to make the rest of the code below a no-op.
1029 */
1030 reloc_callj(fixP);
1031 #endif /* TC_I960 */
1032
1033 add_number += S_GET_VALUE(add_symbolP);
1034 add_number -= md_pcrel_from (fixP);
1035 pcrel = 0; /* Lie. Don't want further pcrel processing. */
1036 fixP->fx_addsy = NULL; /* No relocations please. */
1037 } else {
1038 switch (add_symbol_segment) {
1039 case SEG_ABSOLUTE:
1040 #ifdef TC_I960
1041 reloc_callj(fixP); /* See comment about reloc_callj() above*/
1042 #endif /* TC_I960 */
1043 add_number += S_GET_VALUE(add_symbolP);
1044 fixP->fx_addsy = NULL;
1045 add_symbolP = NULL;
1046 break;
1047 default:
1048 seg_reloc_count ++;
1049 add_number += S_GET_VALUE(add_symbolP);
1050 break;
1051
1052 case SEG_UNKNOWN:
1053 #ifdef TC_I960
1054 if ((int)fixP->fx_bit_fixP == 13) {
1055 /* This is a COBR instruction. They have only a
1056 * 13-bit displacement and are only to be used
1057 * for local branches: flag as error, don't generate
1058 * relocation.
1059 */
1060 as_bad("can't use COBR format with external label");
1061 fixP->fx_addsy = NULL; /* No relocations please. */
1062 continue;
1063 } /* COBR */
1064 #endif /* TC_I960 */
1065 /* FIXME-SOON: I think this is trash, but I'm not sure. xoxorich. */
1066 #ifdef comment
1067 #ifdef OBJ_COFF
1068 if (S_IS_COMMON(add_symbolP))
1069 add_number += S_GET_VALUE(add_symbolP);
1070 #endif /* OBJ_COFF */
1071 #endif /* comment */
1072
1073 ++seg_reloc_count;
1074
1075 break;
1076
1077
1078 } /* switch on symbol seg */
1079 } /* if not in local seg */
1080 } /* if there was a + symbol */
1081
1082 if (pcrel) {
1083 add_number -= md_pcrel_from(fixP);
1084 if (add_symbolP == 0) {
1085 fixP->fx_addsy = & abs_symbol;
1086 ++seg_reloc_count;
1087 } /* if there's an add_symbol */
1088 } /* if pcrel */
1089
1090 if (!fixP->fx_bit_fixP) {
1091 if ((size==1 &&
1092 (add_number& ~0xFF) && (add_number&~0xFF!=(-1&~0xFF))) ||
1093 (size==2 &&
1094 (add_number& ~0xFFFF) && (add_number&~0xFFFF!=(-1&~0xFFFF)))) {
1095 as_bad("Value of %d too large for field of %d bytes at 0x%x",
1096 add_number, size, fragP->fr_address + where);
1097 } /* generic error checking */
1098 } /* not a bit fix */
1099
1100 md_apply_fix(fixP, add_number);
1101 } /* For each fixS in this segment. */
1102
1103 #ifdef OBJ_COFF
1104 #ifdef TC_I960
1105 {
1106 fixS *topP = fixP;
1107
1108 /* two relocs per callj under coff. */
1109 for (fixP = topP; fixP; fixP = fixP->fx_next) {
1110 if (fixP->fx_callj && fixP->fx_addsy != 0) {
1111 ++seg_reloc_count;
1112 } /* if callj and not already fixed. */
1113 } /* for each fix */
1114 }
1115 #endif /* TC_I960 */
1116
1117 #endif /* OBJ_COFF */
1118 return(seg_reloc_count);
1119 } /* fixup_segment() */
1120
1121
1122 static int is_dnrange(f1,f2)
1123 struct frag *f1;
1124 struct frag *f2;
1125 {
1126 while (f1) {
1127 if (f1->fr_next==f2)
1128 return 1;
1129 f1=f1->fr_next;
1130 }
1131 return 0;
1132 } /* is_dnrange() */
1133
1134 /* Append a string onto another string, bumping the pointer along. */
1135 void
1136 append (charPP, fromP, length)
1137 char **charPP;
1138 char *fromP;
1139 unsigned long length;
1140 {
1141 if (length) { /* Don't trust bcopy() of 0 chars. */
1142 bcopy(fromP, *charPP, (int) length);
1143 *charPP += length;
1144 }
1145 }
1146
1147 int section_alignment[SEG_MAXIMUM_ORDINAL];
1148
1149 /*
1150 * This routine records the largest alignment seen for each segment.
1151 * If the beginning of the segment is aligned on the worst-case
1152 * boundary, all of the other alignments within it will work. At
1153 * least one object format really uses this info.
1154 */
1155 void record_alignment(seg, align)
1156 segT seg; /* Segment to which alignment pertains */
1157 int align; /* Alignment, as a power of 2
1158 * (e.g., 1 => 2-byte boundary, 2 => 4-byte boundary, etc.)
1159 */
1160 {
1161
1162 if ( align > section_alignment[(int) seg] ){
1163 section_alignment[(int) seg] = align;
1164 } /* if highest yet */
1165
1166 return;
1167 } /* record_alignment() */
1168
1169 /*
1170 * Local Variables:
1171 * comment-column: 0
1172 * fill-column: 131
1173 * End:
1174 */
1175
1176 /* end of write.c */
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