55c757d3562ff844bbd13c0ee1e972a7681a6d4f
[deliverable/binutils-gdb.git] / gas / write.c
1 /* write.c - emit .o file
2 Copyright 1986, 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 Free Software Foundation, Inc.
5
6 This file is part of GAS, the GNU Assembler.
7
8 GAS is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
11 any later version.
12
13 GAS is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GAS; see the file COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
21 02110-1301, USA. */
22
23 /* This thing should be set up to do byteordering correctly. But... */
24
25 #include "as.h"
26 #include "subsegs.h"
27 #include "obstack.h"
28 #include "output-file.h"
29 #include "dwarf2dbg.h"
30 #include "libbfd.h"
31
32 #ifndef TC_ADJUST_RELOC_COUNT
33 #define TC_ADJUST_RELOC_COUNT(FIX, COUNT)
34 #endif
35
36 #ifndef TC_FORCE_RELOCATION
37 #define TC_FORCE_RELOCATION(FIX) \
38 (generic_force_reloc (FIX))
39 #endif
40
41 #ifndef TC_FORCE_RELOCATION_ABS
42 #define TC_FORCE_RELOCATION_ABS(FIX) \
43 (TC_FORCE_RELOCATION (FIX))
44 #endif
45
46 #ifndef TC_FORCE_RELOCATION_LOCAL
47 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
48 (!(FIX)->fx_pcrel \
49 || TC_FORCE_RELOCATION (FIX))
50 #endif
51
52 #ifndef TC_FORCE_RELOCATION_SUB_SAME
53 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
54 (! SEG_NORMAL (SEG))
55 #endif
56
57 #ifndef TC_FORCE_RELOCATION_SUB_ABS
58 #define TC_FORCE_RELOCATION_SUB_ABS(FIX) 0
59 #endif
60
61 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
62 #ifdef DIFF_EXPR_OK
63 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 0
64 #else
65 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 1
66 #endif
67 #endif
68
69 #ifndef TC_VALIDATE_FIX_SUB
70 #ifdef UNDEFINED_DIFFERENCE_OK
71 /* The PA needs this for PIC code generation. */
72 #define TC_VALIDATE_FIX_SUB(FIX) 1
73 #else
74 #define TC_VALIDATE_FIX_SUB(FIX) \
75 ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
76 || (FIX)->fx_r_type == BFD_RELOC_GPREL16)
77 #endif
78 #endif
79
80 #ifndef TC_LINKRELAX_FIXUP
81 #define TC_LINKRELAX_FIXUP(SEG) 1
82 #endif
83
84 #ifndef MD_APPLY_SYM_VALUE
85 #define MD_APPLY_SYM_VALUE(FIX) 1
86 #endif
87
88 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
89 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
90 #endif
91
92 #ifndef MD_PCREL_FROM_SECTION
93 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
94 #endif
95
96 #ifndef TC_FAKE_LABEL
97 #define TC_FAKE_LABEL(NAME) (strcmp ((NAME), FAKE_LABEL_NAME) == 0)
98 #endif
99
100 /* Positive values of TC_FX_SIZE_SLACK allow a target to define
101 fixups that far past the end of a frag. Having such fixups
102 is of course most most likely a bug in setting fx_size correctly.
103 A negative value disables the fixup check entirely, which is
104 appropriate for something like the Renesas / SuperH SH_COUNT
105 reloc. */
106 #ifndef TC_FX_SIZE_SLACK
107 #define TC_FX_SIZE_SLACK(FIX) 0
108 #endif
109
110 /* Used to control final evaluation of expressions. */
111 int finalize_syms = 0;
112
113 int symbol_table_frozen;
114
115 symbolS *abs_section_sym;
116
117 /* Remember the value of dot when parsing expressions. */
118 addressT dot_value;
119
120 /* Relocs generated by ".reloc" pseudo. */
121 struct reloc_list* reloc_list;
122
123 void print_fixup (fixS *);
124
125 /* We generally attach relocs to frag chains. However, after we have
126 chained these all together into a segment, any relocs we add after
127 that must be attached to a segment. This will include relocs added
128 in md_estimate_size_for_relax, for example. */
129 static int frags_chained = 0;
130
131 static int n_fixups;
132
133 #define RELOC_ENUM enum bfd_reloc_code_real
134
135 /* Create a fixS in obstack 'notes'. */
136
137 static fixS *
138 fix_new_internal (fragS *frag, /* Which frag? */
139 int where, /* Where in that frag? */
140 int size, /* 1, 2, or 4 usually. */
141 symbolS *add_symbol, /* X_add_symbol. */
142 symbolS *sub_symbol, /* X_op_symbol. */
143 offsetT offset, /* X_add_number. */
144 int pcrel, /* TRUE if PC-relative relocation. */
145 RELOC_ENUM r_type ATTRIBUTE_UNUSED /* Relocation type. */)
146 {
147 fixS *fixP;
148
149 n_fixups++;
150
151 fixP = obstack_alloc (&notes, sizeof (fixS));
152
153 fixP->fx_frag = frag;
154 fixP->fx_where = where;
155 fixP->fx_size = size;
156 /* We've made fx_size a narrow field; check that it's wide enough. */
157 if (fixP->fx_size != size)
158 {
159 as_bad (_("field fx_size too small to hold %d"), size);
160 abort ();
161 }
162 fixP->fx_addsy = add_symbol;
163 fixP->fx_subsy = sub_symbol;
164 fixP->fx_offset = offset;
165 fixP->fx_dot_value = dot_value;
166 fixP->fx_pcrel = pcrel;
167 fixP->fx_r_type = r_type;
168 fixP->fx_im_disp = 0;
169 fixP->fx_pcrel_adjust = 0;
170 fixP->fx_bit_fixP = 0;
171 fixP->fx_addnumber = 0;
172 fixP->fx_tcbit = 0;
173 fixP->fx_tcbit2 = 0;
174 fixP->fx_done = 0;
175 fixP->fx_no_overflow = 0;
176 fixP->fx_signed = 0;
177
178 #ifdef USING_CGEN
179 fixP->fx_cgen.insn = NULL;
180 fixP->fx_cgen.opinfo = 0;
181 #endif
182
183 #ifdef TC_FIX_TYPE
184 TC_INIT_FIX_DATA (fixP);
185 #endif
186
187 as_where (&fixP->fx_file, &fixP->fx_line);
188
189 /* Usually, we want relocs sorted numerically, but while
190 comparing to older versions of gas that have relocs
191 reverse sorted, it is convenient to have this compile
192 time option. xoxorich. */
193 {
194
195 fixS **seg_fix_rootP = (frags_chained
196 ? &seg_info (now_seg)->fix_root
197 : &frchain_now->fix_root);
198 fixS **seg_fix_tailP = (frags_chained
199 ? &seg_info (now_seg)->fix_tail
200 : &frchain_now->fix_tail);
201
202 #ifdef REVERSE_SORT_RELOCS
203
204 fixP->fx_next = *seg_fix_rootP;
205 *seg_fix_rootP = fixP;
206
207 #else /* REVERSE_SORT_RELOCS */
208
209 fixP->fx_next = NULL;
210
211 if (*seg_fix_tailP)
212 (*seg_fix_tailP)->fx_next = fixP;
213 else
214 *seg_fix_rootP = fixP;
215 *seg_fix_tailP = fixP;
216
217 #endif /* REVERSE_SORT_RELOCS */
218 }
219
220 return fixP;
221 }
222
223 /* Create a fixup relative to a symbol (plus a constant). */
224
225 fixS *
226 fix_new (fragS *frag, /* Which frag? */
227 int where, /* Where in that frag? */
228 int size, /* 1, 2, or 4 usually. */
229 symbolS *add_symbol, /* X_add_symbol. */
230 offsetT offset, /* X_add_number. */
231 int pcrel, /* TRUE if PC-relative relocation. */
232 RELOC_ENUM r_type /* Relocation type. */)
233 {
234 return fix_new_internal (frag, where, size, add_symbol,
235 (symbolS *) NULL, offset, pcrel, r_type);
236 }
237
238 /* Create a fixup for an expression. Currently we only support fixups
239 for difference expressions. That is itself more than most object
240 file formats support anyhow. */
241
242 fixS *
243 fix_new_exp (fragS *frag, /* Which frag? */
244 int where, /* Where in that frag? */
245 int size, /* 1, 2, or 4 usually. */
246 expressionS *exp, /* Expression. */
247 int pcrel, /* TRUE if PC-relative relocation. */
248 RELOC_ENUM r_type /* Relocation type. */)
249 {
250 symbolS *add = NULL;
251 symbolS *sub = NULL;
252 offsetT off = 0;
253
254 switch (exp->X_op)
255 {
256 case O_absent:
257 break;
258
259 case O_register:
260 as_bad (_("register value used as expression"));
261 break;
262
263 case O_add:
264 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
265 the difference expression cannot immediately be reduced. */
266 {
267 symbolS *stmp = make_expr_symbol (exp);
268
269 exp->X_op = O_symbol;
270 exp->X_op_symbol = 0;
271 exp->X_add_symbol = stmp;
272 exp->X_add_number = 0;
273
274 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
275 }
276
277 case O_symbol_rva:
278 add = exp->X_add_symbol;
279 off = exp->X_add_number;
280 r_type = BFD_RELOC_RVA;
281 break;
282
283 case O_uminus:
284 sub = exp->X_add_symbol;
285 off = exp->X_add_number;
286 break;
287
288 case O_subtract:
289 sub = exp->X_op_symbol;
290 /* Fall through. */
291 case O_symbol:
292 add = exp->X_add_symbol;
293 /* Fall through. */
294 case O_constant:
295 off = exp->X_add_number;
296 break;
297
298 default:
299 add = make_expr_symbol (exp);
300 break;
301 }
302
303 return fix_new_internal (frag, where, size, add, sub, off, pcrel, r_type);
304 }
305
306 /* Generic function to determine whether a fixup requires a relocation. */
307 int
308 generic_force_reloc (fixS *fix)
309 {
310 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
311 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
312 return 1;
313
314 if (fix->fx_addsy == NULL)
315 return 0;
316
317 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
318 }
319
320 /* Append a string onto another string, bumping the pointer along. */
321 void
322 append (char **charPP, char *fromP, unsigned long length)
323 {
324 /* Don't trust memcpy() of 0 chars. */
325 if (length == 0)
326 return;
327
328 memcpy (*charPP, fromP, length);
329 *charPP += length;
330 }
331
332 /* This routine records the largest alignment seen for each segment.
333 If the beginning of the segment is aligned on the worst-case
334 boundary, all of the other alignments within it will work. At
335 least one object format really uses this info. */
336
337 void
338 record_alignment (/* Segment to which alignment pertains. */
339 segT seg,
340 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
341 boundary, 2 => 4-byte boundary, etc.) */
342 int align)
343 {
344 if (seg == absolute_section)
345 return;
346
347 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
348 bfd_set_section_alignment (stdoutput, seg, align);
349 }
350
351 int
352 get_recorded_alignment (segT seg)
353 {
354 if (seg == absolute_section)
355 return 0;
356
357 return bfd_get_section_alignment (stdoutput, seg);
358 }
359
360 /* Reset the section indices after removing the gas created sections. */
361
362 static void
363 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *countparg)
364 {
365 int *countp = (int *) countparg;
366
367 sec->index = *countp;
368 ++*countp;
369 }
370
371 static fragS *
372 chain_frchains_together_1 (segT section, struct frchain *frchp)
373 {
374 fragS dummy, *prev_frag = &dummy;
375 fixS fix_dummy, *prev_fix = &fix_dummy;
376
377 for (; frchp; frchp = frchp->frch_next)
378 {
379 prev_frag->fr_next = frchp->frch_root;
380 prev_frag = frchp->frch_last;
381 assert (prev_frag->fr_type != 0);
382 if (frchp->fix_root != (fixS *) NULL)
383 {
384 if (seg_info (section)->fix_root == (fixS *) NULL)
385 seg_info (section)->fix_root = frchp->fix_root;
386 prev_fix->fx_next = frchp->fix_root;
387 seg_info (section)->fix_tail = frchp->fix_tail;
388 prev_fix = frchp->fix_tail;
389 }
390 }
391 assert (prev_frag->fr_type != 0);
392 assert (prev_frag != &dummy);
393 prev_frag->fr_next = 0;
394 return prev_frag;
395 }
396
397 static void
398 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
399 segT section,
400 void *xxx ATTRIBUTE_UNUSED)
401 {
402 segment_info_type *info;
403
404 /* BFD may have introduced its own sections without using
405 subseg_new, so it is possible that seg_info is NULL. */
406 info = seg_info (section);
407 if (info != (segment_info_type *) NULL)
408 info->frchainP->frch_last
409 = chain_frchains_together_1 (section, info->frchainP);
410
411 /* Now that we've chained the frags together, we must add new fixups
412 to the segment, not to the frag chain. */
413 frags_chained = 1;
414 }
415
416 static void
417 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
418 {
419 switch (fragP->fr_type)
420 {
421 case rs_align:
422 case rs_align_code:
423 case rs_align_test:
424 case rs_org:
425 case rs_space:
426 #ifdef HANDLE_ALIGN
427 HANDLE_ALIGN (fragP);
428 #endif
429 know (fragP->fr_next != NULL);
430 fragP->fr_offset = (fragP->fr_next->fr_address
431 - fragP->fr_address
432 - fragP->fr_fix) / fragP->fr_var;
433 if (fragP->fr_offset < 0)
434 {
435 as_bad_where (fragP->fr_file, fragP->fr_line,
436 _("attempt to .org/.space backwards? (%ld)"),
437 (long) fragP->fr_offset);
438 fragP->fr_offset = 0;
439 }
440 fragP->fr_type = rs_fill;
441 break;
442
443 case rs_fill:
444 break;
445
446 case rs_leb128:
447 {
448 valueT value = S_GET_VALUE (fragP->fr_symbol);
449 int size;
450
451 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
452 fragP->fr_subtype);
453
454 fragP->fr_fix += size;
455 fragP->fr_type = rs_fill;
456 fragP->fr_var = 0;
457 fragP->fr_offset = 0;
458 fragP->fr_symbol = NULL;
459 }
460 break;
461
462 case rs_cfa:
463 eh_frame_convert_frag (fragP);
464 break;
465
466 case rs_dwarf2dbg:
467 dwarf2dbg_convert_frag (fragP);
468 break;
469
470 case rs_machine_dependent:
471 md_convert_frag (stdoutput, sec, fragP);
472
473 assert (fragP->fr_next == NULL
474 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
475 == fragP->fr_fix));
476
477 /* After md_convert_frag, we make the frag into a ".space 0".
478 md_convert_frag() should set up any fixSs and constants
479 required. */
480 frag_wane (fragP);
481 break;
482
483 #ifndef WORKING_DOT_WORD
484 case rs_broken_word:
485 {
486 struct broken_word *lie;
487
488 if (fragP->fr_subtype)
489 {
490 fragP->fr_fix += md_short_jump_size;
491 for (lie = (struct broken_word *) (fragP->fr_symbol);
492 lie && lie->dispfrag == fragP;
493 lie = lie->next_broken_word)
494 if (lie->added == 1)
495 fragP->fr_fix += md_long_jump_size;
496 }
497 frag_wane (fragP);
498 }
499 break;
500 #endif
501
502 default:
503 BAD_CASE (fragP->fr_type);
504 break;
505 }
506 #ifdef md_frag_check
507 md_frag_check (fragP);
508 #endif
509 }
510
511 struct relax_seg_info
512 {
513 int pass;
514 int changed;
515 };
516
517 static void
518 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx)
519 {
520 segment_info_type *seginfo = seg_info (sec);
521 struct relax_seg_info *info = (struct relax_seg_info *) xxx;
522
523 if (seginfo && seginfo->frchainP
524 && relax_segment (seginfo->frchainP->frch_root, sec, info->pass))
525 info->changed = 1;
526 }
527
528 static void
529 size_seg (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
530 {
531 flagword flags;
532 fragS *fragp;
533 segment_info_type *seginfo;
534 int x;
535 valueT size, newsize;
536
537 subseg_change (sec, 0);
538
539 seginfo = seg_info (sec);
540 if (seginfo && seginfo->frchainP)
541 {
542 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
543 cvt_frag_to_fill (sec, fragp);
544 for (fragp = seginfo->frchainP->frch_root;
545 fragp->fr_next;
546 fragp = fragp->fr_next)
547 /* Walk to last elt. */
548 ;
549 size = fragp->fr_address + fragp->fr_fix;
550 }
551 else
552 size = 0;
553
554 flags = bfd_get_section_flags (abfd, sec);
555
556 if (size > 0 && ! seginfo->bss)
557 flags |= SEC_HAS_CONTENTS;
558
559 flags &= ~SEC_RELOC;
560 x = bfd_set_section_flags (abfd, sec, flags);
561 assert (x);
562
563 newsize = md_section_align (sec, size);
564 x = bfd_set_section_size (abfd, sec, newsize);
565 assert (x);
566
567 /* If the size had to be rounded up, add some padding in the last
568 non-empty frag. */
569 assert (newsize >= size);
570 if (size != newsize)
571 {
572 fragS *last = seginfo->frchainP->frch_last;
573 fragp = seginfo->frchainP->frch_root;
574 while (fragp->fr_next != last)
575 fragp = fragp->fr_next;
576 last->fr_address = size;
577 if ((newsize - size) % fragp->fr_var == 0)
578 fragp->fr_offset += (newsize - size) / fragp->fr_var;
579 else
580 /* If we hit this abort, it's likely due to subsegs_finish not
581 providing sufficient alignment on the last frag, and the
582 machine dependent code using alignment frags with fr_var
583 greater than 1. */
584 abort ();
585 }
586
587 #ifdef tc_frob_section
588 tc_frob_section (sec);
589 #endif
590 #ifdef obj_frob_section
591 obj_frob_section (sec);
592 #endif
593 }
594
595 #ifdef DEBUG2
596 static void
597 dump_section_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, FILE *stream)
598 {
599 segment_info_type *seginfo = seg_info (sec);
600 fixS *fixp = seginfo->fix_root;
601
602 if (!fixp)
603 return;
604
605 fprintf (stream, "sec %s relocs:\n", sec->name);
606 while (fixp)
607 {
608 symbolS *s = fixp->fx_addsy;
609
610 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
611 (int) fixp->fx_r_type);
612 if (s == NULL)
613 fprintf (stream, "no sym\n");
614 else
615 {
616 print_symbol_value_1 (stream, s);
617 fprintf (stream, "\n");
618 }
619 fixp = fixp->fx_next;
620 }
621 }
622 #else
623 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
624 #endif
625
626 #ifndef EMIT_SECTION_SYMBOLS
627 #define EMIT_SECTION_SYMBOLS 1
628 #endif
629
630 /* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
631 and check for validity. Convert RELOC_LIST from using U.A fields
632 to U.B fields. */
633 static void
634 resolve_reloc_expr_symbols (void)
635 {
636 struct reloc_list *r;
637
638 for (r = reloc_list; r; r = r->next)
639 {
640 expressionS *symval;
641 symbolS *sym;
642 bfd_vma offset, addend;
643 asection *sec;
644 reloc_howto_type *howto;
645
646 resolve_symbol_value (r->u.a.offset_sym);
647 symval = symbol_get_value_expression (r->u.a.offset_sym);
648
649 offset = 0;
650 sym = NULL;
651 if (symval->X_op == O_constant)
652 sym = r->u.a.offset_sym;
653 else if (symval->X_op == O_symbol)
654 {
655 sym = symval->X_add_symbol;
656 offset = symval->X_add_number;
657 symval = symbol_get_value_expression (symval->X_add_symbol);
658 }
659 if (sym == NULL
660 || symval->X_op != O_constant
661 || (sec = S_GET_SEGMENT (sym)) == NULL
662 || !SEG_NORMAL (sec))
663 {
664 as_bad_where (r->file, r->line, _("invalid offset expression"));
665 sec = NULL;
666 }
667 else
668 offset += S_GET_VALUE (sym);
669
670 sym = NULL;
671 addend = r->u.a.addend;
672 if (r->u.a.sym != NULL)
673 {
674 resolve_symbol_value (r->u.a.sym);
675 symval = symbol_get_value_expression (r->u.a.sym);
676 if (symval->X_op == O_constant)
677 sym = r->u.a.sym;
678 else if (symval->X_op == O_symbol)
679 {
680 sym = symval->X_add_symbol;
681 addend += symval->X_add_number;
682 symval = symbol_get_value_expression (symval->X_add_symbol);
683 }
684 if (symval->X_op != O_constant)
685 {
686 as_bad_where (r->file, r->line, _("invalid reloc expression"));
687 sec = NULL;
688 }
689 else if (sym != NULL)
690 symbol_mark_used_in_reloc (sym);
691 }
692 if (sym == NULL)
693 {
694 if (abs_section_sym == NULL)
695 abs_section_sym = section_symbol (absolute_section);
696 sym = abs_section_sym;
697 }
698
699 howto = r->u.a.howto;
700
701 r->u.b.sec = sec;
702 r->u.b.s = symbol_get_bfdsym (sym);
703 r->u.b.r.sym_ptr_ptr = &r->u.b.s;
704 r->u.b.r.address = offset;
705 r->u.b.r.addend = addend;
706 r->u.b.r.howto = howto;
707 }
708 }
709
710 /* This pass over fixups decides whether symbols can be replaced with
711 section symbols. */
712
713 static void
714 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
715 asection *sec,
716 void *xxx ATTRIBUTE_UNUSED)
717 {
718 segment_info_type *seginfo = seg_info (sec);
719 fixS *fixp;
720
721 if (seginfo == NULL)
722 return;
723
724 dump_section_relocs (abfd, sec, stderr);
725
726 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
727 if (fixp->fx_done)
728 /* Ignore it. */
729 ;
730 else if (fixp->fx_addsy)
731 {
732 symbolS *sym;
733 asection *symsec;
734
735 #ifdef DEBUG5
736 fprintf (stderr, "\n\nadjusting fixup:\n");
737 print_fixup (fixp);
738 #endif
739
740 sym = fixp->fx_addsy;
741
742 /* All symbols should have already been resolved at this
743 point. It is possible to see unresolved expression
744 symbols, though, since they are not in the regular symbol
745 table. */
746 resolve_symbol_value (sym);
747
748 if (fixp->fx_subsy != NULL)
749 resolve_symbol_value (fixp->fx_subsy);
750
751 /* If this symbol is equated to an undefined or common symbol,
752 convert the fixup to being against that symbol. */
753 while (symbol_equated_reloc_p (sym)
754 || S_IS_WEAKREFR (sym))
755 {
756 symbolS *newsym = symbol_get_value_expression (sym)->X_add_symbol;
757 if (sym == newsym)
758 break;
759 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
760 fixp->fx_addsy = newsym;
761 sym = newsym;
762 }
763
764 if (symbol_mri_common_p (sym))
765 {
766 fixp->fx_offset += S_GET_VALUE (sym);
767 fixp->fx_addsy = symbol_get_value_expression (sym)->X_add_symbol;
768 continue;
769 }
770
771 /* If the symbol is undefined, common, weak, or global (ELF
772 shared libs), we can't replace it with the section symbol. */
773 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
774 continue;
775
776 /* Is there some other (target cpu dependent) reason we can't adjust
777 this one? (E.g. relocations involving function addresses on
778 the PA. */
779 #ifdef tc_fix_adjustable
780 if (! tc_fix_adjustable (fixp))
781 continue;
782 #endif
783
784 /* Since we're reducing to section symbols, don't attempt to reduce
785 anything that's already using one. */
786 if (symbol_section_p (sym))
787 continue;
788
789 symsec = S_GET_SEGMENT (sym);
790 if (symsec == NULL)
791 abort ();
792
793 if (bfd_is_abs_section (symsec))
794 {
795 /* The fixup_segment routine normally will not use this
796 symbol in a relocation. */
797 continue;
798 }
799
800 /* Don't try to reduce relocs which refer to non-local symbols
801 in .linkonce sections. It can lead to confusion when a
802 debugging section refers to a .linkonce section. I hope
803 this will always be correct. */
804 if (symsec != sec && ! S_IS_LOCAL (sym))
805 {
806 if ((symsec->flags & SEC_LINK_ONCE) != 0
807 || (IS_ELF
808 /* The GNU toolchain uses an extension for ELF: a
809 section beginning with the magic string
810 .gnu.linkonce is a linkonce section. */
811 && strncmp (segment_name (symsec), ".gnu.linkonce",
812 sizeof ".gnu.linkonce" - 1) == 0))
813 continue;
814 }
815
816 /* Never adjust a reloc against local symbol in a merge section
817 with non-zero addend. */
818 if ((symsec->flags & SEC_MERGE) != 0
819 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
820 continue;
821
822 /* Never adjust a reloc against TLS local symbol. */
823 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
824 continue;
825
826 /* We refetch the segment when calling section_symbol, rather
827 than using symsec, because S_GET_VALUE may wind up changing
828 the section when it calls resolve_symbol_value. */
829 fixp->fx_offset += S_GET_VALUE (sym);
830 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
831 #ifdef DEBUG5
832 fprintf (stderr, "\nadjusted fixup:\n");
833 print_fixup (fixp);
834 #endif
835 }
836
837 dump_section_relocs (abfd, sec, stderr);
838 }
839
840 /* fixup_segment()
841
842 Go through all the fixS's in a segment and see which ones can be
843 handled now. (These consist of fixS where we have since discovered
844 the value of a symbol, or the address of the frag involved.)
845 For each one, call md_apply_fix to put the fix into the frag data.
846
847 Result is a count of how many relocation structs will be needed to
848 handle the remaining fixS's that we couldn't completely handle here.
849 These will be output later by emit_relocations(). */
850
851 static long
852 fixup_segment (fixS *fixP, segT this_segment)
853 {
854 long seg_reloc_count = 0;
855 valueT add_number;
856 fragS *fragP;
857 segT add_symbol_segment = absolute_section;
858
859 if (fixP != NULL && abs_section_sym == NULL)
860 abs_section_sym = section_symbol (absolute_section);
861
862 /* If the linker is doing the relaxing, we must not do any fixups.
863
864 Well, strictly speaking that's not true -- we could do any that
865 are PC-relative and don't cross regions that could change size.
866 And for the i960 we might be able to turn callx/callj into bal
867 anyways in cases where we know the maximum displacement. */
868 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
869 {
870 for (; fixP; fixP = fixP->fx_next)
871 if (!fixP->fx_done)
872 {
873 if (fixP->fx_addsy == NULL)
874 {
875 /* There was no symbol required by this relocation.
876 However, BFD doesn't really handle relocations
877 without symbols well. So fake up a local symbol in
878 the absolute section. */
879 fixP->fx_addsy = abs_section_sym;
880 }
881 symbol_mark_used_in_reloc (fixP->fx_addsy);
882 if (fixP->fx_subsy != NULL)
883 symbol_mark_used_in_reloc (fixP->fx_subsy);
884 seg_reloc_count++;
885 }
886 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
887 return seg_reloc_count;
888 }
889
890 for (; fixP; fixP = fixP->fx_next)
891 {
892 #ifdef DEBUG5
893 fprintf (stderr, "\nprocessing fixup:\n");
894 print_fixup (fixP);
895 #endif
896
897 fragP = fixP->fx_frag;
898 know (fragP);
899 #ifdef TC_VALIDATE_FIX
900 TC_VALIDATE_FIX (fixP, this_segment, skip);
901 #endif
902 add_number = fixP->fx_offset;
903
904 if (fixP->fx_addsy != NULL)
905 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
906
907 if (fixP->fx_subsy != NULL)
908 {
909 segT sub_symbol_segment;
910 resolve_symbol_value (fixP->fx_subsy);
911 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
912 if (fixP->fx_addsy != NULL
913 && sub_symbol_segment == add_symbol_segment
914 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
915 {
916 add_number += S_GET_VALUE (fixP->fx_addsy);
917 add_number -= S_GET_VALUE (fixP->fx_subsy);
918 fixP->fx_offset = add_number;
919 fixP->fx_addsy = NULL;
920 fixP->fx_subsy = NULL;
921 #ifdef TC_M68K
922 /* See the comment below about 68k weirdness. */
923 fixP->fx_pcrel = 0;
924 #endif
925 }
926 else if (sub_symbol_segment == absolute_section
927 && !TC_FORCE_RELOCATION_SUB_ABS (fixP))
928 {
929 add_number -= S_GET_VALUE (fixP->fx_subsy);
930 fixP->fx_offset = add_number;
931 fixP->fx_subsy = NULL;
932 }
933 else if (sub_symbol_segment == this_segment
934 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP))
935 {
936 add_number -= S_GET_VALUE (fixP->fx_subsy);
937 fixP->fx_offset = (add_number + fixP->fx_dot_value
938 + fixP->fx_frag->fr_address);
939
940 /* Make it pc-relative. If the back-end code has not
941 selected a pc-relative reloc, cancel the adjustment
942 we do later on all pc-relative relocs. */
943 if (0
944 #ifdef TC_M68K
945 /* Do this for m68k even if it's already described
946 as pc-relative. On the m68k, an operand of
947 "pc@(foo-.-2)" should address "foo" in a
948 pc-relative mode. */
949 || 1
950 #endif
951 || !fixP->fx_pcrel)
952 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
953 fixP->fx_subsy = NULL;
954 fixP->fx_pcrel = 1;
955 }
956 else if (!TC_VALIDATE_FIX_SUB (fixP))
957 {
958 as_bad_where (fixP->fx_file, fixP->fx_line,
959 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
960 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
961 segment_name (add_symbol_segment),
962 S_GET_NAME (fixP->fx_subsy),
963 segment_name (sub_symbol_segment));
964 }
965 }
966
967 if (fixP->fx_addsy)
968 {
969 if (add_symbol_segment == this_segment
970 && !TC_FORCE_RELOCATION_LOCAL (fixP))
971 {
972 /* This fixup was made when the symbol's segment was
973 SEG_UNKNOWN, but it is now in the local segment.
974 So we know how to do the address without relocation. */
975 add_number += S_GET_VALUE (fixP->fx_addsy);
976 fixP->fx_offset = add_number;
977 if (fixP->fx_pcrel)
978 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
979 fixP->fx_addsy = NULL;
980 fixP->fx_pcrel = 0;
981 }
982 else if (add_symbol_segment == absolute_section
983 && !TC_FORCE_RELOCATION_ABS (fixP))
984 {
985 add_number += S_GET_VALUE (fixP->fx_addsy);
986 fixP->fx_offset = add_number;
987 fixP->fx_addsy = NULL;
988 }
989 else if (add_symbol_segment != undefined_section
990 && ! bfd_is_com_section (add_symbol_segment)
991 && MD_APPLY_SYM_VALUE (fixP))
992 add_number += S_GET_VALUE (fixP->fx_addsy);
993 }
994
995 if (fixP->fx_pcrel)
996 {
997 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
998 if (!fixP->fx_done && fixP->fx_addsy == NULL)
999 {
1000 /* There was no symbol required by this relocation.
1001 However, BFD doesn't really handle relocations
1002 without symbols well. So fake up a local symbol in
1003 the absolute section. */
1004 fixP->fx_addsy = abs_section_sym;
1005 }
1006 }
1007
1008 if (!fixP->fx_done)
1009 md_apply_fix (fixP, &add_number, this_segment);
1010
1011 if (!fixP->fx_done)
1012 {
1013 ++seg_reloc_count;
1014 if (fixP->fx_addsy == NULL)
1015 fixP->fx_addsy = abs_section_sym;
1016 symbol_mark_used_in_reloc (fixP->fx_addsy);
1017 if (fixP->fx_subsy != NULL)
1018 symbol_mark_used_in_reloc (fixP->fx_subsy);
1019 }
1020
1021 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
1022 {
1023 if (fixP->fx_size < sizeof (valueT))
1024 {
1025 valueT mask;
1026
1027 mask = 0;
1028 mask--; /* Set all bits to one. */
1029 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
1030 if ((add_number & mask) != 0 && (add_number & mask) != mask)
1031 {
1032 char buf[50], buf2[50];
1033 sprint_value (buf, fragP->fr_address + fixP->fx_where);
1034 if (add_number > 1000)
1035 sprint_value (buf2, add_number);
1036 else
1037 sprintf (buf2, "%ld", (long) add_number);
1038 as_bad_where (fixP->fx_file, fixP->fx_line,
1039 _("value of %s too large for field of %d bytes at %s"),
1040 buf2, fixP->fx_size, buf);
1041 } /* Generic error checking. */
1042 }
1043 #ifdef WARN_SIGNED_OVERFLOW_WORD
1044 /* Warn if a .word value is too large when treated as a signed
1045 number. We already know it is not too negative. This is to
1046 catch over-large switches generated by gcc on the 68k. */
1047 if (!flag_signed_overflow_ok
1048 && fixP->fx_size == 2
1049 && add_number > 0x7fff)
1050 as_bad_where (fixP->fx_file, fixP->fx_line,
1051 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
1052 (long) add_number,
1053 (long) (fragP->fr_address + fixP->fx_where));
1054 #endif
1055 } /* Not a bit fix. */
1056
1057 #ifdef TC_VALIDATE_FIX
1058 skip: ATTRIBUTE_UNUSED_LABEL
1059 ;
1060 #endif
1061 #ifdef DEBUG5
1062 fprintf (stderr, "result:\n");
1063 print_fixup (fixP);
1064 #endif
1065 } /* For each fixS in this segment. */
1066
1067 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
1068 return seg_reloc_count;
1069 }
1070
1071 static void
1072 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
1073 asection *sec,
1074 void *xxx ATTRIBUTE_UNUSED)
1075 {
1076 segment_info_type *seginfo = seg_info (sec);
1077
1078 fixup_segment (seginfo->fix_root, sec);
1079 }
1080
1081 static void
1082 install_reloc (asection *sec, arelent *reloc, fragS *fragp,
1083 char *file, unsigned int line)
1084 {
1085 char *err;
1086 bfd_reloc_status_type s;
1087 asymbol *sym;
1088
1089 if (reloc->sym_ptr_ptr != NULL
1090 && (sym = *reloc->sym_ptr_ptr) != NULL
1091 && (sym->flags & BSF_KEEP) == 0
1092 && ((sym->flags & BSF_SECTION_SYM) == 0
1093 || !EMIT_SECTION_SYMBOLS
1094 || !bfd_is_abs_section (sym->section)))
1095 as_bad_where (file, line, _("redefined symbol cannot be used on reloc"));
1096
1097 s = bfd_install_relocation (stdoutput, reloc,
1098 fragp->fr_literal, fragp->fr_address,
1099 sec, &err);
1100 switch (s)
1101 {
1102 case bfd_reloc_ok:
1103 break;
1104 case bfd_reloc_overflow:
1105 as_bad_where (file, line, _("relocation overflow"));
1106 break;
1107 case bfd_reloc_outofrange:
1108 as_bad_where (file, line, _("relocation out of range"));
1109 break;
1110 default:
1111 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1112 file, line, s);
1113 }
1114 }
1115
1116 static void
1117 write_relocs (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1118 {
1119 segment_info_type *seginfo = seg_info (sec);
1120 unsigned int i;
1121 unsigned int n;
1122 struct reloc_list *my_reloc_list, **rp, *r;
1123 arelent **relocs;
1124 fixS *fixp;
1125
1126 /* If seginfo is NULL, we did not create this section; don't do
1127 anything with it. */
1128 if (seginfo == NULL)
1129 return;
1130
1131 n = 0;
1132 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
1133 if (!fixp->fx_done)
1134 n++;
1135
1136 #ifdef RELOC_EXPANSION_POSSIBLE
1137 n *= MAX_RELOC_EXPANSION;
1138 #endif
1139
1140 /* Extract relocs for this section from reloc_list. */
1141 rp = &reloc_list;
1142 my_reloc_list = NULL;
1143 while ((r = *rp) != NULL)
1144 {
1145 if (r->u.b.sec == sec)
1146 {
1147 *rp = r->next;
1148 r->next = my_reloc_list;
1149 my_reloc_list = r;
1150 n++;
1151 }
1152 else
1153 rp = &r->next;
1154 }
1155
1156 relocs = xcalloc (n, sizeof (arelent *));
1157
1158 i = 0;
1159 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
1160 {
1161 int j;
1162 int fx_size, slack;
1163 offsetT loc;
1164
1165 if (fixp->fx_done)
1166 continue;
1167
1168 fx_size = fixp->fx_size;
1169 slack = TC_FX_SIZE_SLACK (fixp);
1170 if (slack > 0)
1171 fx_size = fx_size > slack ? fx_size - slack : 0;
1172 loc = fixp->fx_where + fx_size;
1173 if (slack >= 0 && loc > fixp->fx_frag->fr_fix)
1174 as_bad_where (fixp->fx_file, fixp->fx_line,
1175 _("internal error: fixup not contained within frag"));
1176
1177 #ifndef RELOC_EXPANSION_POSSIBLE
1178 {
1179 arelent *reloc = tc_gen_reloc (sec, fixp);
1180
1181 if (!reloc)
1182 continue;
1183 relocs[i++] = reloc;
1184 j = 1;
1185 }
1186 #else
1187 {
1188 arelent **reloc = tc_gen_reloc (sec, fixp);
1189
1190 for (j = 0; reloc[j]; j++)
1191 relocs[i++] = reloc[j];
1192 }
1193 #endif
1194
1195 for ( ; j != 0; --j)
1196 install_reloc (sec, relocs[i - j], fixp->fx_frag,
1197 fixp->fx_file, fixp->fx_line);
1198 }
1199 n = i;
1200
1201 #ifdef DEBUG4
1202 {
1203 unsigned int i, j, nsyms;
1204 asymbol **sympp;
1205 sympp = bfd_get_outsymbols (stdoutput);
1206 nsyms = bfd_get_symcount (stdoutput);
1207 for (i = 0; i < n; i++)
1208 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1209 {
1210 for (j = 0; j < nsyms; j++)
1211 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1212 break;
1213 if (j == nsyms)
1214 abort ();
1215 }
1216 }
1217 #endif
1218
1219 for (r = my_reloc_list; r != NULL; r = r->next)
1220 {
1221 fragS *f;
1222 for (f = seginfo->frchainP->frch_root; f; f = f->fr_next)
1223 if (f->fr_address <= r->u.b.r.address
1224 && r->u.b.r.address < f->fr_address + f->fr_fix)
1225 break;
1226 if (f == NULL)
1227 as_bad_where (r->file, r->line,
1228 _("reloc not within (fixed part of) section"));
1229 else
1230 {
1231 relocs[n++] = &r->u.b.r;
1232 install_reloc (sec, &r->u.b.r, f, r->file, r->line);
1233 }
1234 }
1235
1236 if (n)
1237 {
1238 flagword flags = bfd_get_section_flags (abfd, sec);
1239 flags |= SEC_RELOC;
1240 bfd_set_section_flags (abfd, sec, flags);
1241 bfd_set_reloc (stdoutput, sec, relocs, n);
1242 }
1243
1244 #ifdef SET_SECTION_RELOCS
1245 SET_SECTION_RELOCS (sec, relocs, n);
1246 #endif
1247
1248 #ifdef DEBUG3
1249 {
1250 unsigned int i;
1251 arelent *r;
1252 asymbol *s;
1253 fprintf (stderr, "relocs for sec %s\n", sec->name);
1254 for (i = 0; i < n; i++)
1255 {
1256 r = relocs[i];
1257 s = *r->sym_ptr_ptr;
1258 fprintf (stderr, " reloc %2d @%p off %4lx : sym %-10s addend %lx\n",
1259 i, r, (unsigned long)r->address, s->name, (unsigned long)r->addend);
1260 }
1261 }
1262 #endif
1263 }
1264
1265 static void
1266 write_contents (bfd *abfd ATTRIBUTE_UNUSED,
1267 asection *sec,
1268 void *xxx ATTRIBUTE_UNUSED)
1269 {
1270 segment_info_type *seginfo = seg_info (sec);
1271 addressT offset = 0;
1272 fragS *f;
1273
1274 /* Write out the frags. */
1275 if (seginfo == NULL
1276 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1277 return;
1278
1279 for (f = seginfo->frchainP->frch_root;
1280 f;
1281 f = f->fr_next)
1282 {
1283 int x;
1284 addressT fill_size;
1285 char *fill_literal;
1286 offsetT count;
1287
1288 assert (f->fr_type == rs_fill);
1289 if (f->fr_fix)
1290 {
1291 x = bfd_set_section_contents (stdoutput, sec,
1292 f->fr_literal, (file_ptr) offset,
1293 (bfd_size_type) f->fr_fix);
1294 if (!x)
1295 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1296 bfd_errmsg (bfd_get_error ()));
1297 offset += f->fr_fix;
1298 }
1299 fill_literal = f->fr_literal + f->fr_fix;
1300 fill_size = f->fr_var;
1301 count = f->fr_offset;
1302 assert (count >= 0);
1303 if (fill_size && count)
1304 {
1305 char buf[256];
1306 if (fill_size > sizeof (buf))
1307 {
1308 /* Do it the old way. Can this ever happen? */
1309 while (count--)
1310 {
1311 x = bfd_set_section_contents (stdoutput, sec,
1312 fill_literal,
1313 (file_ptr) offset,
1314 (bfd_size_type) fill_size);
1315 if (!x)
1316 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1317 bfd_errmsg (bfd_get_error ()));
1318 offset += fill_size;
1319 }
1320 }
1321 else
1322 {
1323 /* Build a buffer full of fill objects and output it as
1324 often as necessary. This saves on the overhead of
1325 potentially lots of bfd_set_section_contents calls. */
1326 int n_per_buf, i;
1327 if (fill_size == 1)
1328 {
1329 n_per_buf = sizeof (buf);
1330 memset (buf, *fill_literal, n_per_buf);
1331 }
1332 else
1333 {
1334 char *bufp;
1335 n_per_buf = sizeof (buf) / fill_size;
1336 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1337 memcpy (bufp, fill_literal, fill_size);
1338 }
1339 for (; count > 0; count -= n_per_buf)
1340 {
1341 n_per_buf = n_per_buf > count ? count : n_per_buf;
1342 x = bfd_set_section_contents
1343 (stdoutput, sec, buf, (file_ptr) offset,
1344 (bfd_size_type) n_per_buf * fill_size);
1345 if (!x)
1346 as_fatal (_("cannot write to output file"));
1347 offset += n_per_buf * fill_size;
1348 }
1349 }
1350 }
1351 }
1352 }
1353
1354 static void
1355 merge_data_into_text (void)
1356 {
1357 seg_info (text_section)->frchainP->frch_last->fr_next =
1358 seg_info (data_section)->frchainP->frch_root;
1359 seg_info (text_section)->frchainP->frch_last =
1360 seg_info (data_section)->frchainP->frch_last;
1361 seg_info (data_section)->frchainP = 0;
1362 }
1363
1364 static void
1365 set_symtab (void)
1366 {
1367 int nsyms;
1368 asymbol **asympp;
1369 symbolS *symp;
1370 bfd_boolean result;
1371
1372 /* Count symbols. We can't rely on a count made by the loop in
1373 write_object_file, because *_frob_file may add a new symbol or
1374 two. */
1375 nsyms = 0;
1376 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1377 nsyms++;
1378
1379 if (nsyms)
1380 {
1381 int i;
1382 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1383
1384 asympp = bfd_alloc (stdoutput, amt);
1385 symp = symbol_rootP;
1386 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1387 {
1388 asympp[i] = symbol_get_bfdsym (symp);
1389 if (asympp[i]->flags != BSF_SECTION_SYM
1390 || !(bfd_is_const_section (asympp[i]->section)
1391 && asympp[i]->section->symbol == asympp[i]))
1392 asympp[i]->flags |= BSF_KEEP;
1393 symbol_mark_written (symp);
1394 }
1395 }
1396 else
1397 asympp = 0;
1398 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1399 assert (result);
1400 symbol_table_frozen = 1;
1401 }
1402
1403 /* Finish the subsegments. After every sub-segment, we fake an
1404 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1405 ".fill 0" because that is the kind of frag that requires least
1406 thought. ".align" frags like to have a following frag since that
1407 makes calculating their intended length trivial. */
1408
1409 #ifndef SUB_SEGMENT_ALIGN
1410 #ifdef HANDLE_ALIGN
1411 /* The last subsegment gets an alignment corresponding to the alignment
1412 of the section. This allows proper nop-filling at the end of
1413 code-bearing sections. */
1414 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1415 (!(FRCHAIN)->frch_next ? get_recorded_alignment (SEG) : 0)
1416 #else
1417 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1418 #endif
1419 #endif
1420
1421 void
1422 subsegs_finish (void)
1423 {
1424 struct frchain *frchainP;
1425 asection *s;
1426
1427 for (s = stdoutput->sections; s; s = s->next)
1428 {
1429 segment_info_type *seginfo = seg_info (s);
1430 if (!seginfo)
1431 continue;
1432
1433 for (frchainP = seginfo->frchainP;
1434 frchainP != NULL;
1435 frchainP = frchainP->frch_next)
1436 {
1437 int alignment = 0;
1438
1439 subseg_set (s, frchainP->frch_subseg);
1440
1441 /* This now gets called even if we had errors. In that case,
1442 any alignment is meaningless, and, moreover, will look weird
1443 if we are generating a listing. */
1444 if (!had_errors ())
1445 {
1446 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1447 if ((bfd_get_section_flags (now_seg->owner, now_seg) & SEC_MERGE)
1448 && now_seg->entsize)
1449 {
1450 unsigned int entsize = now_seg->entsize;
1451 int entalign = 0;
1452
1453 while ((entsize & 1) == 0)
1454 {
1455 ++entalign;
1456 entsize >>= 1;
1457 }
1458 if (entalign > alignment)
1459 alignment = entalign;
1460 }
1461 }
1462
1463 if (subseg_text_p (now_seg))
1464 frag_align_code (alignment, 0);
1465 else
1466 frag_align (alignment, 0, 0);
1467
1468 /* frag_align will have left a new frag.
1469 Use this last frag for an empty ".fill".
1470
1471 For this segment ...
1472 Create a last frag. Do not leave a "being filled in frag". */
1473 frag_wane (frag_now);
1474 frag_now->fr_fix = 0;
1475 know (frag_now->fr_next == NULL);
1476 }
1477 }
1478 }
1479
1480 /* Write the object file. */
1481
1482 void
1483 write_object_file (void)
1484 {
1485 struct relax_seg_info rsi;
1486 #ifndef WORKING_DOT_WORD
1487 fragS *fragP; /* Track along all frags. */
1488 #endif
1489
1490 /* Do we really want to write it? */
1491 {
1492 int n_warns, n_errs;
1493 n_warns = had_warnings ();
1494 n_errs = had_errors ();
1495 /* The -Z flag indicates that an object file should be generated,
1496 regardless of warnings and errors. */
1497 if (flag_always_generate_output)
1498 {
1499 if (n_warns || n_errs)
1500 as_warn (_("%d error%s, %d warning%s, generating bad object file"),
1501 n_errs, n_errs == 1 ? "" : "s",
1502 n_warns, n_warns == 1 ? "" : "s");
1503 }
1504 else
1505 {
1506 if (n_errs)
1507 as_fatal (_("%d error%s, %d warning%s, no object file generated"),
1508 n_errs, n_errs == 1 ? "" : "s",
1509 n_warns, n_warns == 1 ? "" : "s");
1510 }
1511 }
1512
1513 #ifdef OBJ_VMS
1514 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1515 a routine to check for the definition of the procedure "_main",
1516 and if so -- fix it up so that it can be program entry point. */
1517 vms_check_for_main ();
1518 #endif /* OBJ_VMS */
1519
1520 /* From now on, we don't care about sub-segments. Build one frag chain
1521 for each segment. Linked thru fr_next. */
1522
1523 /* Remove the sections created by gas for its own purposes. */
1524 {
1525 int i;
1526
1527 bfd_section_list_remove (stdoutput, reg_section);
1528 bfd_section_list_remove (stdoutput, expr_section);
1529 stdoutput->section_count -= 2;
1530 i = 0;
1531 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1532 }
1533
1534 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1535
1536 /* We have two segments. If user gave -R flag, then we must put the
1537 data frags into the text segment. Do this before relaxing so
1538 we know to take advantage of -R and make shorter addresses. */
1539 if (flag_readonly_data_in_text)
1540 {
1541 merge_data_into_text ();
1542 }
1543
1544 rsi.pass = 0;
1545 while (1)
1546 {
1547 #ifndef WORKING_DOT_WORD
1548 /* We need to reset the markers in the broken word list and
1549 associated frags between calls to relax_segment (via
1550 relax_seg). Since the broken word list is global, we do it
1551 once per round, rather than locally in relax_segment for each
1552 segment. */
1553 struct broken_word *brokp;
1554
1555 for (brokp = broken_words;
1556 brokp != (struct broken_word *) NULL;
1557 brokp = brokp->next_broken_word)
1558 {
1559 brokp->added = 0;
1560
1561 if (brokp->dispfrag != (fragS *) NULL
1562 && brokp->dispfrag->fr_type == rs_broken_word)
1563 brokp->dispfrag->fr_subtype = 0;
1564 }
1565 #endif
1566
1567 rsi.changed = 0;
1568 bfd_map_over_sections (stdoutput, relax_seg, &rsi);
1569 rsi.pass++;
1570 if (!rsi.changed)
1571 break;
1572 }
1573
1574 /* Note - Most ports will use the default value of
1575 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
1576 local symbols to be resolved, removing their frag information.
1577 Some ports however, will not have finished relaxing all of
1578 their frags and will still need the local symbol frag
1579 information. These ports can set
1580 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
1581 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
1582
1583 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
1584
1585 /* Relaxation has completed. Freeze all syms. */
1586 finalize_syms = 1;
1587
1588 #ifdef md_post_relax_hook
1589 md_post_relax_hook;
1590 #endif
1591
1592 #ifndef WORKING_DOT_WORD
1593 {
1594 struct broken_word *lie;
1595 struct broken_word **prevP;
1596
1597 prevP = &broken_words;
1598 for (lie = broken_words; lie; lie = lie->next_broken_word)
1599 if (!lie->added)
1600 {
1601 expressionS exp;
1602
1603 subseg_change (lie->seg, lie->subseg);
1604 exp.X_op = O_subtract;
1605 exp.X_add_symbol = lie->add;
1606 exp.X_op_symbol = lie->sub;
1607 exp.X_add_number = lie->addnum;
1608 #ifdef TC_CONS_FIX_NEW
1609 TC_CONS_FIX_NEW (lie->frag,
1610 lie->word_goes_here - lie->frag->fr_literal,
1611 2, &exp);
1612 #else
1613 fix_new_exp (lie->frag,
1614 lie->word_goes_here - lie->frag->fr_literal,
1615 2, &exp, 0, BFD_RELOC_16);
1616 #endif
1617 *prevP = lie->next_broken_word;
1618 }
1619 else
1620 prevP = &(lie->next_broken_word);
1621
1622 for (lie = broken_words; lie;)
1623 {
1624 struct broken_word *untruth;
1625 char *table_ptr;
1626 addressT table_addr;
1627 addressT from_addr, to_addr;
1628 int n, m;
1629
1630 subseg_change (lie->seg, lie->subseg);
1631 fragP = lie->dispfrag;
1632
1633 /* Find out how many broken_words go here. */
1634 n = 0;
1635 for (untruth = lie;
1636 untruth && untruth->dispfrag == fragP;
1637 untruth = untruth->next_broken_word)
1638 if (untruth->added == 1)
1639 n++;
1640
1641 table_ptr = lie->dispfrag->fr_opcode;
1642 table_addr = (lie->dispfrag->fr_address
1643 + (table_ptr - lie->dispfrag->fr_literal));
1644 /* Create the jump around the long jumps. This is a short
1645 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1646 from_addr = table_addr;
1647 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1648 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1649 lie->add);
1650 table_ptr += md_short_jump_size;
1651 table_addr += md_short_jump_size;
1652
1653 for (m = 0;
1654 lie && lie->dispfrag == fragP;
1655 m++, lie = lie->next_broken_word)
1656 {
1657 if (lie->added == 2)
1658 continue;
1659 /* Patch the jump table. */
1660 /* This is the offset from ??? to table_ptr+0. */
1661 to_addr = table_addr - S_GET_VALUE (lie->sub);
1662 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1663 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_addr, lie);
1664 #endif
1665 md_number_to_chars (lie->word_goes_here, to_addr, 2);
1666 for (untruth = lie->next_broken_word;
1667 untruth && untruth->dispfrag == fragP;
1668 untruth = untruth->next_broken_word)
1669 {
1670 if (untruth->use_jump == lie)
1671 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
1672 }
1673
1674 /* Install the long jump. */
1675 /* This is a long jump from table_ptr+0 to the final target. */
1676 from_addr = table_addr;
1677 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1678 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1679 lie->add);
1680 table_ptr += md_long_jump_size;
1681 table_addr += md_long_jump_size;
1682 }
1683 }
1684 }
1685 #endif /* not WORKING_DOT_WORD */
1686
1687 /* Resolve symbol values. This needs to be done before processing
1688 the relocations. */
1689 if (symbol_rootP)
1690 {
1691 symbolS *symp;
1692
1693 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1694 resolve_symbol_value (symp);
1695 }
1696 resolve_local_symbol_values ();
1697 resolve_reloc_expr_symbols ();
1698
1699 PROGRESS (1);
1700
1701 #ifdef tc_frob_file_before_adjust
1702 tc_frob_file_before_adjust ();
1703 #endif
1704 #ifdef obj_frob_file_before_adjust
1705 obj_frob_file_before_adjust ();
1706 #endif
1707
1708 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
1709
1710 #ifdef tc_frob_file_before_fix
1711 tc_frob_file_before_fix ();
1712 #endif
1713 #ifdef obj_frob_file_before_fix
1714 obj_frob_file_before_fix ();
1715 #endif
1716
1717 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
1718
1719 /* Set up symbol table, and write it out. */
1720 if (symbol_rootP)
1721 {
1722 symbolS *symp;
1723 bfd_boolean skip_next_symbol = FALSE;
1724
1725 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1726 {
1727 int punt = 0;
1728 const char *name;
1729
1730 if (skip_next_symbol)
1731 {
1732 /* Don't do anything besides moving the value of the
1733 symbol from the GAS value-field to the BFD value-field. */
1734 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1735 skip_next_symbol = FALSE;
1736 continue;
1737 }
1738
1739 if (symbol_mri_common_p (symp))
1740 {
1741 if (S_IS_EXTERNAL (symp))
1742 as_bad (_("%s: global symbols not supported in common sections"),
1743 S_GET_NAME (symp));
1744 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1745 continue;
1746 }
1747
1748 name = S_GET_NAME (symp);
1749 if (name)
1750 {
1751 const char *name2 =
1752 decode_local_label_name ((char *) S_GET_NAME (symp));
1753 /* They only differ if `name' is a fb or dollar local
1754 label name. */
1755 if (name2 != name && ! S_IS_DEFINED (symp))
1756 as_bad (_("local label `%s' is not defined"), name2);
1757 }
1758
1759 /* Do it again, because adjust_reloc_syms might introduce
1760 more symbols. They'll probably only be section symbols,
1761 but they'll still need to have the values computed. */
1762 resolve_symbol_value (symp);
1763
1764 /* Skip symbols which were equated to undefined or common
1765 symbols. */
1766 if (symbol_equated_reloc_p (symp)
1767 || S_IS_WEAKREFR (symp))
1768 {
1769 const char *name = S_GET_NAME (symp);
1770 if (S_IS_COMMON (symp)
1771 && !TC_FAKE_LABEL (name)
1772 && !S_IS_WEAKREFR (symp)
1773 && (!S_IS_EXTERNAL (symp) || S_IS_LOCAL (symp)))
1774 {
1775 expressionS *e = symbol_get_value_expression (symp);
1776 as_bad (_("Local symbol `%s' can't be equated to common symbol `%s'"),
1777 name, S_GET_NAME (e->X_add_symbol));
1778 }
1779 if (S_GET_SEGMENT (symp) == reg_section)
1780 {
1781 /* Report error only if we know the symbol name. */
1782 if (S_GET_NAME (symp) != reg_section->name)
1783 as_bad (_("can't make global register symbol `%s'"),
1784 name);
1785 }
1786 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1787 continue;
1788 }
1789
1790 #ifdef obj_frob_symbol
1791 obj_frob_symbol (symp, punt);
1792 #endif
1793 #ifdef tc_frob_symbol
1794 if (! punt || symbol_used_in_reloc_p (symp))
1795 tc_frob_symbol (symp, punt);
1796 #endif
1797
1798 /* If we don't want to keep this symbol, splice it out of
1799 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1800 want section symbols. Otherwise, we skip local symbols
1801 and symbols that the frob_symbol macros told us to punt,
1802 but we keep such symbols if they are used in relocs. */
1803 if (symp == abs_section_sym
1804 || (! EMIT_SECTION_SYMBOLS
1805 && symbol_section_p (symp))
1806 /* Note that S_IS_EXTERNAL and S_IS_LOCAL are not always
1807 opposites. Sometimes the former checks flags and the
1808 latter examines the name... */
1809 || (!S_IS_EXTERNAL (symp)
1810 && (punt || S_IS_LOCAL (symp) ||
1811 (S_IS_WEAKREFD (symp) && ! symbol_used_p (symp)))
1812 && ! symbol_used_in_reloc_p (symp)))
1813 {
1814 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1815
1816 /* After symbol_remove, symbol_next(symp) still returns
1817 the one that came after it in the chain. So we don't
1818 need to do any extra cleanup work here. */
1819 continue;
1820 }
1821
1822 /* Make sure we really got a value for the symbol. */
1823 if (! symbol_resolved_p (symp))
1824 {
1825 as_bad (_("can't resolve value for symbol `%s'"),
1826 S_GET_NAME (symp));
1827 symbol_mark_resolved (symp);
1828 }
1829
1830 /* Set the value into the BFD symbol. Up til now the value
1831 has only been kept in the gas symbolS struct. */
1832 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1833
1834 /* A warning construct is a warning symbol followed by the
1835 symbol warned about. Don't let anything object-format or
1836 target-specific muck with it; it's ready for output. */
1837 if (symbol_get_bfdsym (symp)->flags & BSF_WARNING)
1838 skip_next_symbol = TRUE;
1839 }
1840 }
1841
1842 PROGRESS (1);
1843
1844 /* Now do any format-specific adjustments to the symbol table, such
1845 as adding file symbols. */
1846 #ifdef tc_adjust_symtab
1847 tc_adjust_symtab ();
1848 #endif
1849 #ifdef obj_adjust_symtab
1850 obj_adjust_symtab ();
1851 #endif
1852
1853 /* Stop if there is an error. */
1854 if (had_errors ())
1855 return;
1856
1857 /* Now that all the sizes are known, and contents correct, we can
1858 start writing to the file. */
1859 set_symtab ();
1860
1861 /* If *_frob_file changes the symbol value at this point, it is
1862 responsible for moving the changed value into symp->bsym->value
1863 as well. Hopefully all symbol value changing can be done in
1864 *_frob_symbol. */
1865 #ifdef tc_frob_file
1866 tc_frob_file ();
1867 #endif
1868 #ifdef obj_frob_file
1869 obj_frob_file ();
1870 #endif
1871
1872 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
1873
1874 #ifdef tc_frob_file_after_relocs
1875 tc_frob_file_after_relocs ();
1876 #endif
1877 #ifdef obj_frob_file_after_relocs
1878 obj_frob_file_after_relocs ();
1879 #endif
1880
1881 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
1882 }
1883
1884 #ifdef TC_GENERIC_RELAX_TABLE
1885 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
1886
1887 long
1888 relax_frag (segT segment, fragS *fragP, long stretch)
1889 {
1890 const relax_typeS *this_type;
1891 const relax_typeS *start_type;
1892 relax_substateT next_state;
1893 relax_substateT this_state;
1894 offsetT growth;
1895 offsetT aim;
1896 addressT target;
1897 addressT address;
1898 symbolS *symbolP;
1899 const relax_typeS *table;
1900
1901 target = fragP->fr_offset;
1902 address = fragP->fr_address;
1903 table = TC_GENERIC_RELAX_TABLE;
1904 this_state = fragP->fr_subtype;
1905 start_type = this_type = table + this_state;
1906 symbolP = fragP->fr_symbol;
1907
1908 if (symbolP)
1909 {
1910 fragS *sym_frag;
1911
1912 sym_frag = symbol_get_frag (symbolP);
1913
1914 #ifndef DIFF_EXPR_OK
1915 know (sym_frag != NULL);
1916 #endif
1917 know (S_GET_SEGMENT (symbolP) != absolute_section
1918 || sym_frag == &zero_address_frag);
1919 target += S_GET_VALUE (symbolP);
1920
1921 /* If frag has yet to be reached on this pass,
1922 assume it will move by STRETCH just as we did.
1923 If this is not so, it will be because some frag
1924 between grows, and that will force another pass. */
1925
1926 if (stretch != 0
1927 && sym_frag->relax_marker != fragP->relax_marker
1928 && S_GET_SEGMENT (symbolP) == segment)
1929 {
1930 target += stretch;
1931 }
1932 }
1933
1934 aim = target - address - fragP->fr_fix;
1935 #ifdef TC_PCREL_ADJUST
1936 /* Currently only the ns32k family needs this. */
1937 aim += TC_PCREL_ADJUST (fragP);
1938 #endif
1939
1940 #ifdef md_prepare_relax_scan
1941 /* Formerly called M68K_AIM_KLUDGE. */
1942 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
1943 #endif
1944
1945 if (aim < 0)
1946 {
1947 /* Look backwards. */
1948 for (next_state = this_type->rlx_more; next_state;)
1949 if (aim >= this_type->rlx_backward)
1950 next_state = 0;
1951 else
1952 {
1953 /* Grow to next state. */
1954 this_state = next_state;
1955 this_type = table + this_state;
1956 next_state = this_type->rlx_more;
1957 }
1958 }
1959 else
1960 {
1961 /* Look forwards. */
1962 for (next_state = this_type->rlx_more; next_state;)
1963 if (aim <= this_type->rlx_forward)
1964 next_state = 0;
1965 else
1966 {
1967 /* Grow to next state. */
1968 this_state = next_state;
1969 this_type = table + this_state;
1970 next_state = this_type->rlx_more;
1971 }
1972 }
1973
1974 growth = this_type->rlx_length - start_type->rlx_length;
1975 if (growth != 0)
1976 fragP->fr_subtype = this_state;
1977 return growth;
1978 }
1979
1980 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
1981
1982 /* Relax_align. Advance location counter to next address that has 'alignment'
1983 lowest order bits all 0s, return size of adjustment made. */
1984 static relax_addressT
1985 relax_align (register relax_addressT address, /* Address now. */
1986 register int alignment /* Alignment (binary). */)
1987 {
1988 relax_addressT mask;
1989 relax_addressT new_address;
1990
1991 mask = ~((~0) << alignment);
1992 new_address = (address + mask) & (~mask);
1993 #ifdef LINKER_RELAXING_SHRINKS_ONLY
1994 if (linkrelax)
1995 /* We must provide lots of padding, so the linker can discard it
1996 when needed. The linker will not add extra space, ever. */
1997 new_address += (1 << alignment);
1998 #endif
1999 return (new_address - address);
2000 }
2001
2002 /* Now we have a segment, not a crowd of sub-segments, we can make
2003 fr_address values.
2004
2005 Relax the frags.
2006
2007 After this, all frags in this segment have addresses that are correct
2008 within the segment. Since segments live in different file addresses,
2009 these frag addresses may not be the same as final object-file
2010 addresses. */
2011
2012 int
2013 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2014 {
2015 unsigned long frag_count;
2016 struct frag *fragP;
2017 relax_addressT address;
2018 int ret;
2019
2020 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2021 subseg_change (segment, 0);
2022
2023 /* For each frag in segment: count and store (a 1st guess of)
2024 fr_address. */
2025 address = 0;
2026 for (frag_count = 0, fragP = segment_frag_root;
2027 fragP;
2028 fragP = fragP->fr_next, frag_count ++)
2029 {
2030 fragP->relax_marker = 0;
2031 fragP->fr_address = address;
2032 address += fragP->fr_fix;
2033
2034 switch (fragP->fr_type)
2035 {
2036 case rs_fill:
2037 address += fragP->fr_offset * fragP->fr_var;
2038 break;
2039
2040 case rs_align:
2041 case rs_align_code:
2042 case rs_align_test:
2043 {
2044 addressT offset = relax_align (address, (int) fragP->fr_offset);
2045
2046 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2047 offset = 0;
2048
2049 if (offset % fragP->fr_var != 0)
2050 {
2051 as_bad_where (fragP->fr_file, fragP->fr_line,
2052 _("alignment padding (%lu bytes) not a multiple of %ld"),
2053 (unsigned long) offset, (long) fragP->fr_var);
2054 offset -= (offset % fragP->fr_var);
2055 }
2056
2057 address += offset;
2058 }
2059 break;
2060
2061 case rs_org:
2062 case rs_space:
2063 /* Assume .org is nugatory. It will grow with 1st relax. */
2064 break;
2065
2066 case rs_machine_dependent:
2067 /* If fr_symbol is an expression, this call to
2068 resolve_symbol_value sets up the correct segment, which will
2069 likely be needed in md_estimate_size_before_relax. */
2070 if (fragP->fr_symbol)
2071 resolve_symbol_value (fragP->fr_symbol);
2072
2073 address += md_estimate_size_before_relax (fragP, segment);
2074 break;
2075
2076 #ifndef WORKING_DOT_WORD
2077 /* Broken words don't concern us yet. */
2078 case rs_broken_word:
2079 break;
2080 #endif
2081
2082 case rs_leb128:
2083 /* Initial guess is always 1; doing otherwise can result in
2084 stable solutions that are larger than the minimum. */
2085 address += fragP->fr_offset = 1;
2086 break;
2087
2088 case rs_cfa:
2089 address += eh_frame_estimate_size_before_relax (fragP);
2090 break;
2091
2092 case rs_dwarf2dbg:
2093 address += dwarf2dbg_estimate_size_before_relax (fragP);
2094 break;
2095
2096 default:
2097 BAD_CASE (fragP->fr_type);
2098 break;
2099 }
2100 }
2101
2102 /* Do relax(). */
2103 {
2104 unsigned long max_iterations;
2105
2106 /* Cumulative address adjustment. */
2107 offsetT stretch;
2108
2109 /* Have we made any adjustment this pass? We can't just test
2110 stretch because one piece of code may have grown and another
2111 shrank. */
2112 int stretched;
2113
2114 /* Most horrible, but gcc may give us some exception data that
2115 is impossible to assemble, of the form
2116
2117 .align 4
2118 .byte 0, 0
2119 .uleb128 end - start
2120 start:
2121 .space 128*128 - 1
2122 .align 4
2123 end:
2124
2125 If the leb128 is two bytes in size, then end-start is 128*128,
2126 which requires a three byte leb128. If the leb128 is three
2127 bytes in size, then end-start is 128*128-1, which requires a
2128 two byte leb128. We work around this dilemma by inserting
2129 an extra 4 bytes of alignment just after the .align. This
2130 works because the data after the align is accessed relative to
2131 the end label.
2132
2133 This counter is used in a tiny state machine to detect
2134 whether a leb128 followed by an align is impossible to
2135 relax. */
2136 int rs_leb128_fudge = 0;
2137
2138 /* We want to prevent going into an infinite loop where one frag grows
2139 depending upon the location of a symbol which is in turn moved by
2140 the growing frag. eg:
2141
2142 foo = .
2143 .org foo+16
2144 foo = .
2145
2146 So we dictate that this algorithm can be at most O2. */
2147 max_iterations = frag_count * frag_count;
2148 /* Check for overflow. */
2149 if (max_iterations < frag_count)
2150 max_iterations = frag_count;
2151
2152 ret = 0;
2153 do
2154 {
2155 stretch = 0;
2156 stretched = 0;
2157
2158 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2159 {
2160 offsetT growth = 0;
2161 addressT was_address;
2162 offsetT offset;
2163 symbolS *symbolP;
2164
2165 fragP->relax_marker ^= 1;
2166 was_address = fragP->fr_address;
2167 address = fragP->fr_address += stretch;
2168 symbolP = fragP->fr_symbol;
2169 offset = fragP->fr_offset;
2170
2171 switch (fragP->fr_type)
2172 {
2173 case rs_fill: /* .fill never relaxes. */
2174 growth = 0;
2175 break;
2176
2177 #ifndef WORKING_DOT_WORD
2178 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2179 for it I do not want to write it. I do not want to have
2180 anything to do with it. This is not the proper way to
2181 implement this misfeature. */
2182 case rs_broken_word:
2183 {
2184 struct broken_word *lie;
2185 struct broken_word *untruth;
2186
2187 /* Yes this is ugly (storing the broken_word pointer
2188 in the symbol slot). Still, this whole chunk of
2189 code is ugly, and I don't feel like doing anything
2190 about it. Think of it as stubbornness in action. */
2191 growth = 0;
2192 for (lie = (struct broken_word *) (fragP->fr_symbol);
2193 lie && lie->dispfrag == fragP;
2194 lie = lie->next_broken_word)
2195 {
2196
2197 if (lie->added)
2198 continue;
2199
2200 offset = (S_GET_VALUE (lie->add)
2201 + lie->addnum
2202 - S_GET_VALUE (lie->sub));
2203 if (offset <= -32768 || offset >= 32767)
2204 {
2205 if (flag_warn_displacement)
2206 {
2207 char buf[50];
2208 sprint_value (buf, (addressT) lie->addnum);
2209 as_warn_where (fragP->fr_file, fragP->fr_line,
2210 _(".word %s-%s+%s didn't fit"),
2211 S_GET_NAME (lie->add),
2212 S_GET_NAME (lie->sub),
2213 buf);
2214 }
2215 lie->added = 1;
2216 if (fragP->fr_subtype == 0)
2217 {
2218 fragP->fr_subtype++;
2219 growth += md_short_jump_size;
2220 }
2221 for (untruth = lie->next_broken_word;
2222 untruth && untruth->dispfrag == lie->dispfrag;
2223 untruth = untruth->next_broken_word)
2224 if ((symbol_get_frag (untruth->add)
2225 == symbol_get_frag (lie->add))
2226 && (S_GET_VALUE (untruth->add)
2227 == S_GET_VALUE (lie->add)))
2228 {
2229 untruth->added = 2;
2230 untruth->use_jump = lie;
2231 }
2232 growth += md_long_jump_size;
2233 }
2234 }
2235
2236 break;
2237 } /* case rs_broken_word */
2238 #endif
2239 case rs_align:
2240 case rs_align_code:
2241 case rs_align_test:
2242 {
2243 addressT oldoff, newoff;
2244
2245 oldoff = relax_align (was_address + fragP->fr_fix,
2246 (int) offset);
2247 newoff = relax_align (address + fragP->fr_fix,
2248 (int) offset);
2249
2250 if (fragP->fr_subtype != 0)
2251 {
2252 if (oldoff > fragP->fr_subtype)
2253 oldoff = 0;
2254 if (newoff > fragP->fr_subtype)
2255 newoff = 0;
2256 }
2257
2258 growth = newoff - oldoff;
2259
2260 /* If this align happens to follow a leb128 and
2261 we have determined that the leb128 is bouncing
2262 in size, then break the cycle by inserting an
2263 extra alignment. */
2264 if (growth < 0
2265 && (rs_leb128_fudge & 16) != 0
2266 && (rs_leb128_fudge & 15) >= 2)
2267 {
2268 segment_info_type *seginfo = seg_info (segment);
2269 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2270 struct frag *newf;
2271
2272 newf = frag_alloc (ob);
2273 obstack_blank_fast (ob, fragP->fr_var);
2274 obstack_finish (ob);
2275 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2276 memcpy (newf->fr_literal,
2277 fragP->fr_literal + fragP->fr_fix,
2278 fragP->fr_var);
2279 newf->fr_type = rs_fill;
2280 newf->fr_fix = 0;
2281 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2282 / fragP->fr_var);
2283 if (newf->fr_offset * newf->fr_var
2284 != (offsetT) 1 << fragP->fr_offset)
2285 {
2286 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2287 newf->fr_var = 1;
2288 }
2289 /* Include growth of new frag, because rs_fill
2290 frags don't normally grow. */
2291 growth += newf->fr_offset * newf->fr_var;
2292 /* The new frag address is newoff. Adjust this
2293 for the amount we'll add when we process the
2294 new frag. */
2295 newf->fr_address = newoff - stretch - growth;
2296 newf->relax_marker ^= 1;
2297 fragP->fr_next = newf;
2298 #ifdef DEBUG
2299 as_warn (_("padding added"));
2300 #endif
2301 }
2302 }
2303 break;
2304
2305 case rs_org:
2306 {
2307 addressT target = offset;
2308 addressT after;
2309
2310 if (symbolP)
2311 {
2312 /* Convert from an actual address to an octet offset
2313 into the section. Here it is assumed that the
2314 section's VMA is zero, and can omit subtracting it
2315 from the symbol's value to get the address offset. */
2316 know (S_GET_SEGMENT (symbolP)->vma == 0);
2317 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2318 }
2319
2320 know (fragP->fr_next);
2321 after = fragP->fr_next->fr_address + stretch;
2322 growth = target - after;
2323 if (growth < 0)
2324 {
2325 growth = 0;
2326
2327 /* Don't error on first few frag relax passes.
2328 The symbol might be an expression involving
2329 symbol values from other sections. If those
2330 sections have not yet been processed their
2331 frags will all have zero addresses, so we
2332 will calculate incorrect values for them. The
2333 number of passes we allow before giving an
2334 error is somewhat arbitrary. It should be at
2335 least one, with larger values requiring
2336 increasingly contrived dependencies between
2337 frags to trigger a false error. */
2338 if (pass < 2)
2339 {
2340 /* Force another pass. */
2341 ret = 1;
2342 break;
2343 }
2344
2345 /* Growth may be negative, but variable part of frag
2346 cannot have fewer than 0 chars. That is, we can't
2347 .org backwards. */
2348 as_bad_where (fragP->fr_file, fragP->fr_line,
2349 _("attempt to move .org backwards"));
2350
2351 /* We've issued an error message. Change the
2352 frag to avoid cascading errors. */
2353 fragP->fr_type = rs_align;
2354 fragP->fr_subtype = 0;
2355 fragP->fr_offset = 0;
2356 fragP->fr_fix = after - address;
2357 }
2358 }
2359 break;
2360
2361 case rs_space:
2362 growth = 0;
2363 if (symbolP)
2364 {
2365 offsetT amount;
2366
2367 amount = S_GET_VALUE (symbolP);
2368 if (S_GET_SEGMENT (symbolP) != absolute_section
2369 || S_IS_COMMON (symbolP)
2370 || ! S_IS_DEFINED (symbolP))
2371 {
2372 as_bad_where (fragP->fr_file, fragP->fr_line,
2373 _(".space specifies non-absolute value"));
2374 /* Prevent repeat of this error message. */
2375 fragP->fr_symbol = 0;
2376 }
2377 else if (amount < 0)
2378 {
2379 /* Don't error on first few frag relax passes.
2380 See rs_org comment for a longer explanation. */
2381 if (pass < 2)
2382 {
2383 ret = 1;
2384 break;
2385 }
2386
2387 as_warn_where (fragP->fr_file, fragP->fr_line,
2388 _(".space or .fill with negative value, ignored"));
2389 fragP->fr_symbol = 0;
2390 }
2391 else
2392 growth = (was_address + fragP->fr_fix + amount
2393 - fragP->fr_next->fr_address);
2394 }
2395 break;
2396
2397 case rs_machine_dependent:
2398 #ifdef md_relax_frag
2399 growth = md_relax_frag (segment, fragP, stretch);
2400 #else
2401 #ifdef TC_GENERIC_RELAX_TABLE
2402 /* The default way to relax a frag is to look through
2403 TC_GENERIC_RELAX_TABLE. */
2404 growth = relax_frag (segment, fragP, stretch);
2405 #endif /* TC_GENERIC_RELAX_TABLE */
2406 #endif
2407 break;
2408
2409 case rs_leb128:
2410 {
2411 valueT value;
2412 offsetT size;
2413
2414 value = resolve_symbol_value (fragP->fr_symbol);
2415 size = sizeof_leb128 (value, fragP->fr_subtype);
2416 growth = size - fragP->fr_offset;
2417 fragP->fr_offset = size;
2418 }
2419 break;
2420
2421 case rs_cfa:
2422 growth = eh_frame_relax_frag (fragP);
2423 break;
2424
2425 case rs_dwarf2dbg:
2426 growth = dwarf2dbg_relax_frag (fragP);
2427 break;
2428
2429 default:
2430 BAD_CASE (fragP->fr_type);
2431 break;
2432 }
2433 if (growth)
2434 {
2435 stretch += growth;
2436 stretched = 1;
2437 if (fragP->fr_type == rs_leb128)
2438 rs_leb128_fudge += 16;
2439 else if (fragP->fr_type == rs_align
2440 && (rs_leb128_fudge & 16) != 0
2441 && stretch == 0)
2442 rs_leb128_fudge += 16;
2443 else
2444 rs_leb128_fudge = 0;
2445 }
2446 }
2447
2448 if (stretch == 0
2449 && (rs_leb128_fudge & 16) == 0
2450 && (rs_leb128_fudge & -16) != 0)
2451 rs_leb128_fudge += 1;
2452 else
2453 rs_leb128_fudge = 0;
2454 }
2455 /* Until nothing further to relax. */
2456 while (stretched && -- max_iterations);
2457
2458 if (stretched)
2459 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
2460 segment_name (segment));
2461 }
2462
2463 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2464 if (fragP->last_fr_address != fragP->fr_address)
2465 {
2466 fragP->last_fr_address = fragP->fr_address;
2467 ret = 1;
2468 }
2469 return ret;
2470 }
2471
2472 void
2473 number_to_chars_bigendian (char *buf, valueT val, int n)
2474 {
2475 if (n <= 0)
2476 abort ();
2477 while (n--)
2478 {
2479 buf[n] = val & 0xff;
2480 val >>= 8;
2481 }
2482 }
2483
2484 void
2485 number_to_chars_littleendian (char *buf, valueT val, int n)
2486 {
2487 if (n <= 0)
2488 abort ();
2489 while (n--)
2490 {
2491 *buf++ = val & 0xff;
2492 val >>= 8;
2493 }
2494 }
2495
2496 void
2497 write_print_statistics (FILE *file)
2498 {
2499 fprintf (file, "fixups: %d\n", n_fixups);
2500 }
2501
2502 /* For debugging. */
2503 extern int indent_level;
2504
2505 void
2506 print_fixup (fixS *fixp)
2507 {
2508 indent_level = 1;
2509 fprintf (stderr, "fix ");
2510 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
2511 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
2512 if (fixp->fx_pcrel)
2513 fprintf (stderr, " pcrel");
2514 if (fixp->fx_pcrel_adjust)
2515 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2516 if (fixp->fx_im_disp)
2517 {
2518 #ifdef TC_NS32K
2519 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2520 #else
2521 fprintf (stderr, " im_disp");
2522 #endif
2523 }
2524 if (fixp->fx_tcbit)
2525 fprintf (stderr, " tcbit");
2526 if (fixp->fx_done)
2527 fprintf (stderr, " done");
2528 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
2529 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
2530 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
2531 (long) fixp->fx_where,
2532 (unsigned long) fixp->fx_offset,
2533 (unsigned long) fixp->fx_addnumber);
2534 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2535 fixp->fx_r_type);
2536 if (fixp->fx_addsy)
2537 {
2538 fprintf (stderr, "\n +<");
2539 print_symbol_value_1 (stderr, fixp->fx_addsy);
2540 fprintf (stderr, ">");
2541 }
2542 if (fixp->fx_subsy)
2543 {
2544 fprintf (stderr, "\n -<");
2545 print_symbol_value_1 (stderr, fixp->fx_subsy);
2546 fprintf (stderr, ">");
2547 }
2548 fprintf (stderr, "\n");
2549 #ifdef TC_FIX_DATA_PRINT
2550 TC_FIX_DATA_PRINT (stderr, fixp);
2551 #endif
2552 }
This page took 0.097928 seconds and 4 git commands to generate.