2009-08-31 H.J. Lu <hongjiu.lu@intel.com>
[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 md_register_arithmetic
58 # define md_register_arithmetic 1
59 #endif
60
61 #ifndef TC_FORCE_RELOCATION_SUB_ABS
62 #define TC_FORCE_RELOCATION_SUB_ABS(FIX, SEG) \
63 (!md_register_arithmetic && (SEG) == reg_section)
64 #endif
65
66 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
67 #ifdef DIFF_EXPR_OK
68 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) \
69 (!md_register_arithmetic && (SEG) == reg_section)
70 #else
71 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) 1
72 #endif
73 #endif
74
75 #ifndef TC_VALIDATE_FIX_SUB
76 #ifdef UNDEFINED_DIFFERENCE_OK
77 /* The PA needs this for PIC code generation. */
78 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
79 (md_register_arithmetic || (SEG) != reg_section)
80 #else
81 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
82 ((md_register_arithmetic || (SEG) != reg_section) \
83 && ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
84 || (FIX)->fx_r_type == BFD_RELOC_GPREL16))
85 #endif
86 #endif
87
88 #ifndef TC_LINKRELAX_FIXUP
89 #define TC_LINKRELAX_FIXUP(SEG) 1
90 #endif
91
92 #ifndef MD_APPLY_SYM_VALUE
93 #define MD_APPLY_SYM_VALUE(FIX) 1
94 #endif
95
96 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
97 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
98 #endif
99
100 #ifndef MD_PCREL_FROM_SECTION
101 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
102 #endif
103
104 #ifndef TC_FAKE_LABEL
105 #define TC_FAKE_LABEL(NAME) (strcmp ((NAME), FAKE_LABEL_NAME) == 0)
106 #endif
107
108 /* Positive values of TC_FX_SIZE_SLACK allow a target to define
109 fixups that far past the end of a frag. Having such fixups
110 is of course most most likely a bug in setting fx_size correctly.
111 A negative value disables the fixup check entirely, which is
112 appropriate for something like the Renesas / SuperH SH_COUNT
113 reloc. */
114 #ifndef TC_FX_SIZE_SLACK
115 #define TC_FX_SIZE_SLACK(FIX) 0
116 #endif
117
118 /* Used to control final evaluation of expressions. */
119 int finalize_syms = 0;
120
121 int symbol_table_frozen;
122
123 symbolS *abs_section_sym;
124
125 /* Remember the value of dot when parsing expressions. */
126 addressT dot_value;
127
128 /* Relocs generated by ".reloc" pseudo. */
129 struct reloc_list* reloc_list;
130
131 void print_fixup (fixS *);
132
133 /* We generally attach relocs to frag chains. However, after we have
134 chained these all together into a segment, any relocs we add after
135 that must be attached to a segment. This will include relocs added
136 in md_estimate_size_for_relax, for example. */
137 static int frags_chained = 0;
138
139 static int n_fixups;
140
141 #define RELOC_ENUM enum bfd_reloc_code_real
142
143 /* Create a fixS in obstack 'notes'. */
144
145 static fixS *
146 fix_new_internal (fragS *frag, /* Which frag? */
147 int where, /* Where in that frag? */
148 int size, /* 1, 2, or 4 usually. */
149 symbolS *add_symbol, /* X_add_symbol. */
150 symbolS *sub_symbol, /* X_op_symbol. */
151 offsetT offset, /* X_add_number. */
152 int pcrel, /* TRUE if PC-relative relocation. */
153 RELOC_ENUM r_type ATTRIBUTE_UNUSED /* Relocation type. */)
154 {
155 fixS *fixP;
156
157 n_fixups++;
158
159 fixP = obstack_alloc (&notes, sizeof (fixS));
160
161 fixP->fx_frag = frag;
162 fixP->fx_where = where;
163 fixP->fx_size = size;
164 /* We've made fx_size a narrow field; check that it's wide enough. */
165 if (fixP->fx_size != size)
166 {
167 as_bad (_("field fx_size too small to hold %d"), size);
168 abort ();
169 }
170 fixP->fx_addsy = add_symbol;
171 fixP->fx_subsy = sub_symbol;
172 fixP->fx_offset = offset;
173 fixP->fx_dot_value = dot_value;
174 fixP->fx_pcrel = pcrel;
175 fixP->fx_r_type = r_type;
176 fixP->fx_im_disp = 0;
177 fixP->fx_pcrel_adjust = 0;
178 fixP->fx_bit_fixP = 0;
179 fixP->fx_addnumber = 0;
180 fixP->fx_tcbit = 0;
181 fixP->fx_tcbit2 = 0;
182 fixP->fx_done = 0;
183 fixP->fx_no_overflow = 0;
184 fixP->fx_signed = 0;
185
186 #ifdef USING_CGEN
187 fixP->fx_cgen.insn = NULL;
188 fixP->fx_cgen.opinfo = 0;
189 #endif
190
191 #ifdef TC_FIX_TYPE
192 TC_INIT_FIX_DATA (fixP);
193 #endif
194
195 as_where (&fixP->fx_file, &fixP->fx_line);
196
197 /* Usually, we want relocs sorted numerically, but while
198 comparing to older versions of gas that have relocs
199 reverse sorted, it is convenient to have this compile
200 time option. xoxorich. */
201 {
202
203 fixS **seg_fix_rootP = (frags_chained
204 ? &seg_info (now_seg)->fix_root
205 : &frchain_now->fix_root);
206 fixS **seg_fix_tailP = (frags_chained
207 ? &seg_info (now_seg)->fix_tail
208 : &frchain_now->fix_tail);
209
210 #ifdef REVERSE_SORT_RELOCS
211
212 fixP->fx_next = *seg_fix_rootP;
213 *seg_fix_rootP = fixP;
214
215 #else /* REVERSE_SORT_RELOCS */
216
217 fixP->fx_next = NULL;
218
219 if (*seg_fix_tailP)
220 (*seg_fix_tailP)->fx_next = fixP;
221 else
222 *seg_fix_rootP = fixP;
223 *seg_fix_tailP = fixP;
224
225 #endif /* REVERSE_SORT_RELOCS */
226 }
227
228 return fixP;
229 }
230
231 /* Create a fixup relative to a symbol (plus a constant). */
232
233 fixS *
234 fix_new (fragS *frag, /* Which frag? */
235 int where, /* Where in that frag? */
236 int size, /* 1, 2, or 4 usually. */
237 symbolS *add_symbol, /* X_add_symbol. */
238 offsetT offset, /* X_add_number. */
239 int pcrel, /* TRUE if PC-relative relocation. */
240 RELOC_ENUM r_type /* Relocation type. */)
241 {
242 return fix_new_internal (frag, where, size, add_symbol,
243 (symbolS *) NULL, offset, pcrel, r_type);
244 }
245
246 /* Create a fixup for an expression. Currently we only support fixups
247 for difference expressions. That is itself more than most object
248 file formats support anyhow. */
249
250 fixS *
251 fix_new_exp (fragS *frag, /* Which frag? */
252 int where, /* Where in that frag? */
253 int size, /* 1, 2, or 4 usually. */
254 expressionS *exp, /* Expression. */
255 int pcrel, /* TRUE if PC-relative relocation. */
256 RELOC_ENUM r_type /* Relocation type. */)
257 {
258 symbolS *add = NULL;
259 symbolS *sub = NULL;
260 offsetT off = 0;
261
262 switch (exp->X_op)
263 {
264 case O_absent:
265 break;
266
267 case O_register:
268 as_bad (_("register value used as expression"));
269 break;
270
271 case O_add:
272 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
273 the difference expression cannot immediately be reduced. */
274 {
275 symbolS *stmp = make_expr_symbol (exp);
276
277 exp->X_op = O_symbol;
278 exp->X_op_symbol = 0;
279 exp->X_add_symbol = stmp;
280 exp->X_add_number = 0;
281
282 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
283 }
284
285 case O_symbol_rva:
286 add = exp->X_add_symbol;
287 off = exp->X_add_number;
288 r_type = BFD_RELOC_RVA;
289 break;
290
291 case O_uminus:
292 sub = exp->X_add_symbol;
293 off = exp->X_add_number;
294 break;
295
296 case O_subtract:
297 sub = exp->X_op_symbol;
298 /* Fall through. */
299 case O_symbol:
300 add = exp->X_add_symbol;
301 /* Fall through. */
302 case O_constant:
303 off = exp->X_add_number;
304 break;
305
306 default:
307 add = make_expr_symbol (exp);
308 break;
309 }
310
311 return fix_new_internal (frag, where, size, add, sub, off, pcrel, r_type);
312 }
313
314 /* Generic function to determine whether a fixup requires a relocation. */
315 int
316 generic_force_reloc (fixS *fix)
317 {
318 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
319 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
320 return 1;
321
322 if (fix->fx_addsy == NULL)
323 return 0;
324
325 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
326 }
327
328 /* Append a string onto another string, bumping the pointer along. */
329 void
330 append (char **charPP, char *fromP, unsigned long length)
331 {
332 /* Don't trust memcpy() of 0 chars. */
333 if (length == 0)
334 return;
335
336 memcpy (*charPP, fromP, length);
337 *charPP += length;
338 }
339
340 /* This routine records the largest alignment seen for each segment.
341 If the beginning of the segment is aligned on the worst-case
342 boundary, all of the other alignments within it will work. At
343 least one object format really uses this info. */
344
345 void
346 record_alignment (/* Segment to which alignment pertains. */
347 segT seg,
348 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
349 boundary, 2 => 4-byte boundary, etc.) */
350 int align)
351 {
352 if (seg == absolute_section)
353 return;
354
355 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
356 bfd_set_section_alignment (stdoutput, seg, align);
357 }
358
359 int
360 get_recorded_alignment (segT seg)
361 {
362 if (seg == absolute_section)
363 return 0;
364
365 return bfd_get_section_alignment (stdoutput, seg);
366 }
367
368 /* Reset the section indices after removing the gas created sections. */
369
370 static void
371 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *countparg)
372 {
373 int *countp = (int *) countparg;
374
375 sec->index = *countp;
376 ++*countp;
377 }
378
379 static fragS *
380 chain_frchains_together_1 (segT section, struct frchain *frchp)
381 {
382 fragS dummy, *prev_frag = &dummy;
383 fixS fix_dummy, *prev_fix = &fix_dummy;
384
385 for (; frchp; frchp = frchp->frch_next)
386 {
387 prev_frag->fr_next = frchp->frch_root;
388 prev_frag = frchp->frch_last;
389 gas_assert (prev_frag->fr_type != 0);
390 if (frchp->fix_root != (fixS *) NULL)
391 {
392 if (seg_info (section)->fix_root == (fixS *) NULL)
393 seg_info (section)->fix_root = frchp->fix_root;
394 prev_fix->fx_next = frchp->fix_root;
395 seg_info (section)->fix_tail = frchp->fix_tail;
396 prev_fix = frchp->fix_tail;
397 }
398 }
399 gas_assert (prev_frag->fr_type != 0);
400 gas_assert (prev_frag != &dummy);
401 prev_frag->fr_next = 0;
402 return prev_frag;
403 }
404
405 static void
406 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
407 segT section,
408 void *xxx ATTRIBUTE_UNUSED)
409 {
410 segment_info_type *info;
411
412 /* BFD may have introduced its own sections without using
413 subseg_new, so it is possible that seg_info is NULL. */
414 info = seg_info (section);
415 if (info != (segment_info_type *) NULL)
416 info->frchainP->frch_last
417 = chain_frchains_together_1 (section, info->frchainP);
418
419 /* Now that we've chained the frags together, we must add new fixups
420 to the segment, not to the frag chain. */
421 frags_chained = 1;
422 }
423
424 static void
425 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
426 {
427 switch (fragP->fr_type)
428 {
429 case rs_align:
430 case rs_align_code:
431 case rs_align_test:
432 case rs_org:
433 case rs_space:
434 #ifdef HANDLE_ALIGN
435 HANDLE_ALIGN (fragP);
436 #endif
437 know (fragP->fr_next != NULL);
438 fragP->fr_offset = (fragP->fr_next->fr_address
439 - fragP->fr_address
440 - fragP->fr_fix) / fragP->fr_var;
441 if (fragP->fr_offset < 0)
442 {
443 as_bad_where (fragP->fr_file, fragP->fr_line,
444 _("attempt to .org/.space backwards? (%ld)"),
445 (long) fragP->fr_offset);
446 fragP->fr_offset = 0;
447 }
448 fragP->fr_type = rs_fill;
449 break;
450
451 case rs_fill:
452 break;
453
454 case rs_leb128:
455 {
456 valueT value = S_GET_VALUE (fragP->fr_symbol);
457 int size;
458
459 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
460 fragP->fr_subtype);
461
462 fragP->fr_fix += size;
463 fragP->fr_type = rs_fill;
464 fragP->fr_var = 0;
465 fragP->fr_offset = 0;
466 fragP->fr_symbol = NULL;
467 }
468 break;
469
470 case rs_cfa:
471 eh_frame_convert_frag (fragP);
472 break;
473
474 case rs_dwarf2dbg:
475 dwarf2dbg_convert_frag (fragP);
476 break;
477
478 case rs_machine_dependent:
479 md_convert_frag (stdoutput, sec, fragP);
480
481 gas_assert (fragP->fr_next == NULL
482 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
483 == fragP->fr_fix));
484
485 /* After md_convert_frag, we make the frag into a ".space 0".
486 md_convert_frag() should set up any fixSs and constants
487 required. */
488 frag_wane (fragP);
489 break;
490
491 #ifndef WORKING_DOT_WORD
492 case rs_broken_word:
493 {
494 struct broken_word *lie;
495
496 if (fragP->fr_subtype)
497 {
498 fragP->fr_fix += md_short_jump_size;
499 for (lie = (struct broken_word *) (fragP->fr_symbol);
500 lie && lie->dispfrag == fragP;
501 lie = lie->next_broken_word)
502 if (lie->added == 1)
503 fragP->fr_fix += md_long_jump_size;
504 }
505 frag_wane (fragP);
506 }
507 break;
508 #endif
509
510 default:
511 BAD_CASE (fragP->fr_type);
512 break;
513 }
514 #ifdef md_frag_check
515 md_frag_check (fragP);
516 #endif
517 }
518
519 struct relax_seg_info
520 {
521 int pass;
522 int changed;
523 };
524
525 static void
526 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx)
527 {
528 segment_info_type *seginfo = seg_info (sec);
529 struct relax_seg_info *info = (struct relax_seg_info *) xxx;
530
531 if (seginfo && seginfo->frchainP
532 && relax_segment (seginfo->frchainP->frch_root, sec, info->pass))
533 info->changed = 1;
534 }
535
536 static void
537 size_seg (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
538 {
539 flagword flags;
540 fragS *fragp;
541 segment_info_type *seginfo;
542 int x;
543 valueT size, newsize;
544
545 subseg_change (sec, 0);
546
547 seginfo = seg_info (sec);
548 if (seginfo && seginfo->frchainP)
549 {
550 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
551 cvt_frag_to_fill (sec, fragp);
552 for (fragp = seginfo->frchainP->frch_root;
553 fragp->fr_next;
554 fragp = fragp->fr_next)
555 /* Walk to last elt. */
556 ;
557 size = fragp->fr_address + fragp->fr_fix;
558 }
559 else
560 size = 0;
561
562 flags = bfd_get_section_flags (abfd, sec);
563 if (size == 0 && bfd_get_section_size (sec) != 0 &&
564 (flags & SEC_HAS_CONTENTS) != 0)
565 return;
566
567 if (size > 0 && ! seginfo->bss)
568 flags |= SEC_HAS_CONTENTS;
569
570 flags &= ~SEC_RELOC;
571 x = bfd_set_section_flags (abfd, sec, flags);
572 gas_assert (x);
573
574 newsize = md_section_align (sec, size);
575 x = bfd_set_section_size (abfd, sec, newsize);
576 gas_assert (x);
577
578 /* If the size had to be rounded up, add some padding in the last
579 non-empty frag. */
580 gas_assert (newsize >= size);
581 if (size != newsize)
582 {
583 fragS *last = seginfo->frchainP->frch_last;
584 fragp = seginfo->frchainP->frch_root;
585 while (fragp->fr_next != last)
586 fragp = fragp->fr_next;
587 last->fr_address = size;
588 if ((newsize - size) % fragp->fr_var == 0)
589 fragp->fr_offset += (newsize - size) / fragp->fr_var;
590 else
591 /* If we hit this abort, it's likely due to subsegs_finish not
592 providing sufficient alignment on the last frag, and the
593 machine dependent code using alignment frags with fr_var
594 greater than 1. */
595 abort ();
596 }
597
598 #ifdef tc_frob_section
599 tc_frob_section (sec);
600 #endif
601 #ifdef obj_frob_section
602 obj_frob_section (sec);
603 #endif
604 }
605
606 #ifdef DEBUG2
607 static void
608 dump_section_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, FILE *stream)
609 {
610 segment_info_type *seginfo = seg_info (sec);
611 fixS *fixp = seginfo->fix_root;
612
613 if (!fixp)
614 return;
615
616 fprintf (stream, "sec %s relocs:\n", sec->name);
617 while (fixp)
618 {
619 symbolS *s = fixp->fx_addsy;
620
621 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
622 (int) fixp->fx_r_type);
623 if (s == NULL)
624 fprintf (stream, "no sym\n");
625 else
626 {
627 print_symbol_value_1 (stream, s);
628 fprintf (stream, "\n");
629 }
630 fixp = fixp->fx_next;
631 }
632 }
633 #else
634 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
635 #endif
636
637 #ifndef EMIT_SECTION_SYMBOLS
638 #define EMIT_SECTION_SYMBOLS 1
639 #endif
640
641 /* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
642 and check for validity. Convert RELOC_LIST from using U.A fields
643 to U.B fields. */
644 static void
645 resolve_reloc_expr_symbols (void)
646 {
647 struct reloc_list *r;
648
649 for (r = reloc_list; r; r = r->next)
650 {
651 expressionS *symval;
652 symbolS *sym;
653 bfd_vma offset, addend;
654 asection *sec;
655 reloc_howto_type *howto;
656
657 resolve_symbol_value (r->u.a.offset_sym);
658 symval = symbol_get_value_expression (r->u.a.offset_sym);
659
660 offset = 0;
661 sym = NULL;
662 if (symval->X_op == O_constant)
663 sym = r->u.a.offset_sym;
664 else if (symval->X_op == O_symbol)
665 {
666 sym = symval->X_add_symbol;
667 offset = symval->X_add_number;
668 symval = symbol_get_value_expression (symval->X_add_symbol);
669 }
670 if (sym == NULL
671 || symval->X_op != O_constant
672 || (sec = S_GET_SEGMENT (sym)) == NULL
673 || !SEG_NORMAL (sec))
674 {
675 as_bad_where (r->file, r->line, _("invalid offset expression"));
676 sec = NULL;
677 }
678 else
679 offset += S_GET_VALUE (sym);
680
681 sym = NULL;
682 addend = r->u.a.addend;
683 if (r->u.a.sym != NULL)
684 {
685 resolve_symbol_value (r->u.a.sym);
686 symval = symbol_get_value_expression (r->u.a.sym);
687 if (symval->X_op == O_constant)
688 sym = r->u.a.sym;
689 else if (symval->X_op == O_symbol)
690 {
691 sym = symval->X_add_symbol;
692 addend += symval->X_add_number;
693 symval = symbol_get_value_expression (symval->X_add_symbol);
694 }
695 if (symval->X_op != O_constant)
696 {
697 as_bad_where (r->file, r->line, _("invalid reloc expression"));
698 sec = NULL;
699 }
700 else if (sym != NULL)
701 symbol_mark_used_in_reloc (sym);
702 }
703 if (sym == NULL)
704 {
705 if (abs_section_sym == NULL)
706 abs_section_sym = section_symbol (absolute_section);
707 sym = abs_section_sym;
708 }
709
710 howto = r->u.a.howto;
711
712 r->u.b.sec = sec;
713 r->u.b.s = symbol_get_bfdsym (sym);
714 r->u.b.r.sym_ptr_ptr = &r->u.b.s;
715 r->u.b.r.address = offset;
716 r->u.b.r.addend = addend;
717 r->u.b.r.howto = howto;
718 }
719 }
720
721 /* This pass over fixups decides whether symbols can be replaced with
722 section symbols. */
723
724 static void
725 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
726 asection *sec,
727 void *xxx ATTRIBUTE_UNUSED)
728 {
729 segment_info_type *seginfo = seg_info (sec);
730 fixS *fixp;
731
732 if (seginfo == NULL)
733 return;
734
735 dump_section_relocs (abfd, sec, stderr);
736
737 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
738 if (fixp->fx_done)
739 /* Ignore it. */
740 ;
741 else if (fixp->fx_addsy)
742 {
743 symbolS *sym;
744 asection *symsec;
745
746 #ifdef DEBUG5
747 fprintf (stderr, "\n\nadjusting fixup:\n");
748 print_fixup (fixp);
749 #endif
750
751 sym = fixp->fx_addsy;
752
753 /* All symbols should have already been resolved at this
754 point. It is possible to see unresolved expression
755 symbols, though, since they are not in the regular symbol
756 table. */
757 resolve_symbol_value (sym);
758
759 if (fixp->fx_subsy != NULL)
760 resolve_symbol_value (fixp->fx_subsy);
761
762 /* If this symbol is equated to an undefined or common symbol,
763 convert the fixup to being against that symbol. */
764 while (symbol_equated_reloc_p (sym)
765 || S_IS_WEAKREFR (sym))
766 {
767 symbolS *newsym = symbol_get_value_expression (sym)->X_add_symbol;
768 if (sym == newsym)
769 break;
770 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
771 fixp->fx_addsy = newsym;
772 sym = newsym;
773 }
774
775 if (symbol_mri_common_p (sym))
776 {
777 fixp->fx_offset += S_GET_VALUE (sym);
778 fixp->fx_addsy = symbol_get_value_expression (sym)->X_add_symbol;
779 continue;
780 }
781
782 /* If the symbol is undefined, common, weak, or global (ELF
783 shared libs), we can't replace it with the section symbol. */
784 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
785 continue;
786
787 /* Is there some other (target cpu dependent) reason we can't adjust
788 this one? (E.g. relocations involving function addresses on
789 the PA. */
790 #ifdef tc_fix_adjustable
791 if (! tc_fix_adjustable (fixp))
792 continue;
793 #endif
794
795 /* Since we're reducing to section symbols, don't attempt to reduce
796 anything that's already using one. */
797 if (symbol_section_p (sym))
798 continue;
799
800 symsec = S_GET_SEGMENT (sym);
801 if (symsec == NULL)
802 abort ();
803
804 if (bfd_is_abs_section (symsec))
805 {
806 /* The fixup_segment routine normally will not use this
807 symbol in a relocation. */
808 continue;
809 }
810
811 /* Don't try to reduce relocs which refer to non-local symbols
812 in .linkonce sections. It can lead to confusion when a
813 debugging section refers to a .linkonce section. I hope
814 this will always be correct. */
815 if (symsec != sec && ! S_IS_LOCAL (sym))
816 {
817 if ((symsec->flags & SEC_LINK_ONCE) != 0
818 || (IS_ELF
819 /* The GNU toolchain uses an extension for ELF: a
820 section beginning with the magic string
821 .gnu.linkonce is a linkonce section. */
822 && strncmp (segment_name (symsec), ".gnu.linkonce",
823 sizeof ".gnu.linkonce" - 1) == 0))
824 continue;
825 }
826
827 /* Never adjust a reloc against local symbol in a merge section
828 with non-zero addend. */
829 if ((symsec->flags & SEC_MERGE) != 0
830 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
831 continue;
832
833 /* Never adjust a reloc against TLS local symbol. */
834 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
835 continue;
836
837 /* We refetch the segment when calling section_symbol, rather
838 than using symsec, because S_GET_VALUE may wind up changing
839 the section when it calls resolve_symbol_value. */
840 fixp->fx_offset += S_GET_VALUE (sym);
841 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
842 #ifdef DEBUG5
843 fprintf (stderr, "\nadjusted fixup:\n");
844 print_fixup (fixp);
845 #endif
846 }
847
848 dump_section_relocs (abfd, sec, stderr);
849 }
850
851 /* fixup_segment()
852
853 Go through all the fixS's in a segment and see which ones can be
854 handled now. (These consist of fixS where we have since discovered
855 the value of a symbol, or the address of the frag involved.)
856 For each one, call md_apply_fix to put the fix into the frag data.
857
858 Result is a count of how many relocation structs will be needed to
859 handle the remaining fixS's that we couldn't completely handle here.
860 These will be output later by emit_relocations(). */
861
862 static long
863 fixup_segment (fixS *fixP, segT this_segment)
864 {
865 long seg_reloc_count = 0;
866 valueT add_number;
867 fragS *fragP;
868 segT add_symbol_segment = absolute_section;
869
870 if (fixP != NULL && abs_section_sym == NULL)
871 abs_section_sym = section_symbol (absolute_section);
872
873 /* If the linker is doing the relaxing, we must not do any fixups.
874
875 Well, strictly speaking that's not true -- we could do any that
876 are PC-relative and don't cross regions that could change size.
877 And for the i960 we might be able to turn callx/callj into bal
878 anyways in cases where we know the maximum displacement. */
879 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
880 {
881 for (; fixP; fixP = fixP->fx_next)
882 if (!fixP->fx_done)
883 {
884 if (fixP->fx_addsy == NULL)
885 {
886 /* There was no symbol required by this relocation.
887 However, BFD doesn't really handle relocations
888 without symbols well. So fake up a local symbol in
889 the absolute section. */
890 fixP->fx_addsy = abs_section_sym;
891 }
892 symbol_mark_used_in_reloc (fixP->fx_addsy);
893 if (fixP->fx_subsy != NULL)
894 symbol_mark_used_in_reloc (fixP->fx_subsy);
895 seg_reloc_count++;
896 }
897 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
898 return seg_reloc_count;
899 }
900
901 for (; fixP; fixP = fixP->fx_next)
902 {
903 #ifdef DEBUG5
904 fprintf (stderr, "\nprocessing fixup:\n");
905 print_fixup (fixP);
906 #endif
907
908 fragP = fixP->fx_frag;
909 know (fragP);
910 #ifdef TC_VALIDATE_FIX
911 TC_VALIDATE_FIX (fixP, this_segment, skip);
912 #endif
913 add_number = fixP->fx_offset;
914
915 if (fixP->fx_addsy != NULL)
916 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
917
918 if (fixP->fx_subsy != NULL)
919 {
920 segT sub_symbol_segment;
921 resolve_symbol_value (fixP->fx_subsy);
922 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
923 if (fixP->fx_addsy != NULL
924 && sub_symbol_segment == add_symbol_segment
925 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
926 {
927 add_number += S_GET_VALUE (fixP->fx_addsy);
928 add_number -= S_GET_VALUE (fixP->fx_subsy);
929 fixP->fx_offset = add_number;
930 fixP->fx_addsy = NULL;
931 fixP->fx_subsy = NULL;
932 #ifdef TC_M68K
933 /* See the comment below about 68k weirdness. */
934 fixP->fx_pcrel = 0;
935 #endif
936 }
937 else if (sub_symbol_segment == absolute_section
938 && !TC_FORCE_RELOCATION_SUB_ABS (fixP, add_symbol_segment))
939 {
940 add_number -= S_GET_VALUE (fixP->fx_subsy);
941 fixP->fx_offset = add_number;
942 fixP->fx_subsy = NULL;
943 }
944 else if (sub_symbol_segment == this_segment
945 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP, add_symbol_segment))
946 {
947 add_number -= S_GET_VALUE (fixP->fx_subsy);
948 fixP->fx_offset = (add_number + fixP->fx_dot_value
949 + fixP->fx_frag->fr_address);
950
951 /* Make it pc-relative. If the back-end code has not
952 selected a pc-relative reloc, cancel the adjustment
953 we do later on all pc-relative relocs. */
954 if (0
955 #ifdef TC_M68K
956 /* Do this for m68k even if it's already described
957 as pc-relative. On the m68k, an operand of
958 "pc@(foo-.-2)" should address "foo" in a
959 pc-relative mode. */
960 || 1
961 #endif
962 || !fixP->fx_pcrel)
963 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
964 fixP->fx_subsy = NULL;
965 fixP->fx_pcrel = 1;
966 }
967 else if (!TC_VALIDATE_FIX_SUB (fixP, add_symbol_segment))
968 {
969 if (!md_register_arithmetic
970 && (add_symbol_segment == reg_section
971 || sub_symbol_segment == reg_section))
972 as_bad_where (fixP->fx_file, fixP->fx_line,
973 _("register value used as expression"));
974 else
975 as_bad_where (fixP->fx_file, fixP->fx_line,
976 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
977 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
978 segment_name (add_symbol_segment),
979 S_GET_NAME (fixP->fx_subsy),
980 segment_name (sub_symbol_segment));
981 }
982 }
983
984 if (fixP->fx_addsy)
985 {
986 if (add_symbol_segment == this_segment
987 && !TC_FORCE_RELOCATION_LOCAL (fixP))
988 {
989 /* This fixup was made when the symbol's segment was
990 SEG_UNKNOWN, but it is now in the local segment.
991 So we know how to do the address without relocation. */
992 add_number += S_GET_VALUE (fixP->fx_addsy);
993 fixP->fx_offset = add_number;
994 if (fixP->fx_pcrel)
995 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
996 fixP->fx_addsy = NULL;
997 fixP->fx_pcrel = 0;
998 }
999 else if (add_symbol_segment == absolute_section
1000 && !TC_FORCE_RELOCATION_ABS (fixP))
1001 {
1002 add_number += S_GET_VALUE (fixP->fx_addsy);
1003 fixP->fx_offset = add_number;
1004 fixP->fx_addsy = NULL;
1005 }
1006 else if (add_symbol_segment != undefined_section
1007 && ! bfd_is_com_section (add_symbol_segment)
1008 && MD_APPLY_SYM_VALUE (fixP))
1009 add_number += S_GET_VALUE (fixP->fx_addsy);
1010 }
1011
1012 if (fixP->fx_pcrel)
1013 {
1014 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1015 if (!fixP->fx_done && fixP->fx_addsy == NULL)
1016 {
1017 /* There was no symbol required by this relocation.
1018 However, BFD doesn't really handle relocations
1019 without symbols well. So fake up a local symbol in
1020 the absolute section. */
1021 fixP->fx_addsy = abs_section_sym;
1022 }
1023 }
1024
1025 if (!fixP->fx_done)
1026 md_apply_fix (fixP, &add_number, this_segment);
1027
1028 if (!fixP->fx_done)
1029 {
1030 ++seg_reloc_count;
1031 if (fixP->fx_addsy == NULL)
1032 fixP->fx_addsy = abs_section_sym;
1033 symbol_mark_used_in_reloc (fixP->fx_addsy);
1034 if (fixP->fx_subsy != NULL)
1035 symbol_mark_used_in_reloc (fixP->fx_subsy);
1036 }
1037
1038 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
1039 {
1040 if (fixP->fx_size < sizeof (valueT))
1041 {
1042 valueT mask;
1043
1044 mask = 0;
1045 mask--; /* Set all bits to one. */
1046 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
1047 if ((add_number & mask) != 0 && (add_number & mask) != mask)
1048 {
1049 char buf[50], buf2[50];
1050 sprint_value (buf, fragP->fr_address + fixP->fx_where);
1051 if (add_number > 1000)
1052 sprint_value (buf2, add_number);
1053 else
1054 sprintf (buf2, "%ld", (long) add_number);
1055 as_bad_where (fixP->fx_file, fixP->fx_line,
1056 _("value of %s too large for field of %d bytes at %s"),
1057 buf2, fixP->fx_size, buf);
1058 } /* Generic error checking. */
1059 }
1060 #ifdef WARN_SIGNED_OVERFLOW_WORD
1061 /* Warn if a .word value is too large when treated as a signed
1062 number. We already know it is not too negative. This is to
1063 catch over-large switches generated by gcc on the 68k. */
1064 if (!flag_signed_overflow_ok
1065 && fixP->fx_size == 2
1066 && add_number > 0x7fff)
1067 as_bad_where (fixP->fx_file, fixP->fx_line,
1068 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
1069 (long) add_number,
1070 (long) (fragP->fr_address + fixP->fx_where));
1071 #endif
1072 } /* Not a bit fix. */
1073
1074 #ifdef TC_VALIDATE_FIX
1075 skip: ATTRIBUTE_UNUSED_LABEL
1076 ;
1077 #endif
1078 #ifdef DEBUG5
1079 fprintf (stderr, "result:\n");
1080 print_fixup (fixP);
1081 #endif
1082 } /* For each fixS in this segment. */
1083
1084 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
1085 return seg_reloc_count;
1086 }
1087
1088 static void
1089 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
1090 asection *sec,
1091 void *xxx ATTRIBUTE_UNUSED)
1092 {
1093 segment_info_type *seginfo = seg_info (sec);
1094
1095 fixup_segment (seginfo->fix_root, sec);
1096 }
1097
1098 static void
1099 install_reloc (asection *sec, arelent *reloc, fragS *fragp,
1100 char *file, unsigned int line)
1101 {
1102 char *err;
1103 bfd_reloc_status_type s;
1104 asymbol *sym;
1105
1106 if (reloc->sym_ptr_ptr != NULL
1107 && (sym = *reloc->sym_ptr_ptr) != NULL
1108 && (sym->flags & BSF_KEEP) == 0
1109 && ((sym->flags & BSF_SECTION_SYM) == 0
1110 || (EMIT_SECTION_SYMBOLS
1111 && !bfd_is_abs_section (sym->section))))
1112 as_bad_where (file, line, _("redefined symbol cannot be used on reloc"));
1113
1114 s = bfd_install_relocation (stdoutput, reloc,
1115 fragp->fr_literal, fragp->fr_address,
1116 sec, &err);
1117 switch (s)
1118 {
1119 case bfd_reloc_ok:
1120 break;
1121 case bfd_reloc_overflow:
1122 as_bad_where (file, line, _("relocation overflow"));
1123 break;
1124 case bfd_reloc_outofrange:
1125 as_bad_where (file, line, _("relocation out of range"));
1126 break;
1127 default:
1128 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1129 file, line, s);
1130 }
1131 }
1132
1133 static void
1134 write_relocs (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1135 {
1136 segment_info_type *seginfo = seg_info (sec);
1137 unsigned int i;
1138 unsigned int n;
1139 struct reloc_list *my_reloc_list, **rp, *r;
1140 arelent **relocs;
1141 fixS *fixp;
1142
1143 /* If seginfo is NULL, we did not create this section; don't do
1144 anything with it. */
1145 if (seginfo == NULL)
1146 return;
1147
1148 n = 0;
1149 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
1150 if (!fixp->fx_done)
1151 n++;
1152
1153 #ifdef RELOC_EXPANSION_POSSIBLE
1154 n *= MAX_RELOC_EXPANSION;
1155 #endif
1156
1157 /* Extract relocs for this section from reloc_list. */
1158 rp = &reloc_list;
1159 my_reloc_list = NULL;
1160 while ((r = *rp) != NULL)
1161 {
1162 if (r->u.b.sec == sec)
1163 {
1164 *rp = r->next;
1165 r->next = my_reloc_list;
1166 my_reloc_list = r;
1167 n++;
1168 }
1169 else
1170 rp = &r->next;
1171 }
1172
1173 relocs = xcalloc (n, sizeof (arelent *));
1174
1175 i = 0;
1176 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
1177 {
1178 int j;
1179 int fx_size, slack;
1180 offsetT loc;
1181
1182 if (fixp->fx_done)
1183 continue;
1184
1185 fx_size = fixp->fx_size;
1186 slack = TC_FX_SIZE_SLACK (fixp);
1187 if (slack > 0)
1188 fx_size = fx_size > slack ? fx_size - slack : 0;
1189 loc = fixp->fx_where + fx_size;
1190 if (slack >= 0 && loc > fixp->fx_frag->fr_fix)
1191 as_bad_where (fixp->fx_file, fixp->fx_line,
1192 _("internal error: fixup not contained within frag"));
1193
1194 #ifndef RELOC_EXPANSION_POSSIBLE
1195 {
1196 arelent *reloc = tc_gen_reloc (sec, fixp);
1197
1198 if (!reloc)
1199 continue;
1200 relocs[i++] = reloc;
1201 j = 1;
1202 }
1203 #else
1204 {
1205 arelent **reloc = tc_gen_reloc (sec, fixp);
1206
1207 for (j = 0; reloc[j]; j++)
1208 relocs[i++] = reloc[j];
1209 }
1210 #endif
1211
1212 for ( ; j != 0; --j)
1213 install_reloc (sec, relocs[i - j], fixp->fx_frag,
1214 fixp->fx_file, fixp->fx_line);
1215 }
1216 n = i;
1217
1218 #ifdef DEBUG4
1219 {
1220 unsigned int i, j, nsyms;
1221 asymbol **sympp;
1222 sympp = bfd_get_outsymbols (stdoutput);
1223 nsyms = bfd_get_symcount (stdoutput);
1224 for (i = 0; i < n; i++)
1225 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1226 {
1227 for (j = 0; j < nsyms; j++)
1228 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1229 break;
1230 if (j == nsyms)
1231 abort ();
1232 }
1233 }
1234 #endif
1235
1236 for (r = my_reloc_list; r != NULL; r = r->next)
1237 {
1238 fragS *f;
1239 for (f = seginfo->frchainP->frch_root; f; f = f->fr_next)
1240 if (f->fr_address <= r->u.b.r.address
1241 && r->u.b.r.address < f->fr_address + f->fr_fix)
1242 break;
1243 if (f == NULL)
1244 as_bad_where (r->file, r->line,
1245 _("reloc not within (fixed part of) section"));
1246 else
1247 {
1248 relocs[n++] = &r->u.b.r;
1249 install_reloc (sec, &r->u.b.r, f, r->file, r->line);
1250 }
1251 }
1252
1253 if (n)
1254 {
1255 flagword flags = bfd_get_section_flags (abfd, sec);
1256 flags |= SEC_RELOC;
1257 bfd_set_section_flags (abfd, sec, flags);
1258 bfd_set_reloc (stdoutput, sec, relocs, n);
1259 }
1260
1261 #ifdef SET_SECTION_RELOCS
1262 SET_SECTION_RELOCS (sec, relocs, n);
1263 #endif
1264
1265 #ifdef DEBUG3
1266 {
1267 unsigned int i;
1268 arelent *r;
1269 asymbol *s;
1270 fprintf (stderr, "relocs for sec %s\n", sec->name);
1271 for (i = 0; i < n; i++)
1272 {
1273 r = relocs[i];
1274 s = *r->sym_ptr_ptr;
1275 fprintf (stderr, " reloc %2d @%p off %4lx : sym %-10s addend %lx\n",
1276 i, r, (unsigned long)r->address, s->name, (unsigned long)r->addend);
1277 }
1278 }
1279 #endif
1280 }
1281
1282 static void
1283 write_contents (bfd *abfd ATTRIBUTE_UNUSED,
1284 asection *sec,
1285 void *xxx ATTRIBUTE_UNUSED)
1286 {
1287 segment_info_type *seginfo = seg_info (sec);
1288 addressT offset = 0;
1289 fragS *f;
1290
1291 /* Write out the frags. */
1292 if (seginfo == NULL
1293 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1294 return;
1295
1296 for (f = seginfo->frchainP->frch_root;
1297 f;
1298 f = f->fr_next)
1299 {
1300 int x;
1301 addressT fill_size;
1302 char *fill_literal;
1303 offsetT count;
1304
1305 gas_assert (f->fr_type == rs_fill);
1306 if (f->fr_fix)
1307 {
1308 x = bfd_set_section_contents (stdoutput, sec,
1309 f->fr_literal, (file_ptr) offset,
1310 (bfd_size_type) f->fr_fix);
1311 if (!x)
1312 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1313 bfd_errmsg (bfd_get_error ()));
1314 offset += f->fr_fix;
1315 }
1316 fill_literal = f->fr_literal + f->fr_fix;
1317 fill_size = f->fr_var;
1318 count = f->fr_offset;
1319 gas_assert (count >= 0);
1320 if (fill_size && count)
1321 {
1322 char buf[256];
1323 if (fill_size > sizeof (buf))
1324 {
1325 /* Do it the old way. Can this ever happen? */
1326 while (count--)
1327 {
1328 x = bfd_set_section_contents (stdoutput, sec,
1329 fill_literal,
1330 (file_ptr) offset,
1331 (bfd_size_type) fill_size);
1332 if (!x)
1333 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1334 bfd_errmsg (bfd_get_error ()));
1335 offset += fill_size;
1336 }
1337 }
1338 else
1339 {
1340 /* Build a buffer full of fill objects and output it as
1341 often as necessary. This saves on the overhead of
1342 potentially lots of bfd_set_section_contents calls. */
1343 int n_per_buf, i;
1344 if (fill_size == 1)
1345 {
1346 n_per_buf = sizeof (buf);
1347 memset (buf, *fill_literal, n_per_buf);
1348 }
1349 else
1350 {
1351 char *bufp;
1352 n_per_buf = sizeof (buf) / fill_size;
1353 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1354 memcpy (bufp, fill_literal, fill_size);
1355 }
1356 for (; count > 0; count -= n_per_buf)
1357 {
1358 n_per_buf = n_per_buf > count ? count : n_per_buf;
1359 x = bfd_set_section_contents
1360 (stdoutput, sec, buf, (file_ptr) offset,
1361 (bfd_size_type) n_per_buf * fill_size);
1362 if (!x)
1363 as_fatal (_("cannot write to output file"));
1364 offset += n_per_buf * fill_size;
1365 }
1366 }
1367 }
1368 }
1369 }
1370
1371 static void
1372 merge_data_into_text (void)
1373 {
1374 seg_info (text_section)->frchainP->frch_last->fr_next =
1375 seg_info (data_section)->frchainP->frch_root;
1376 seg_info (text_section)->frchainP->frch_last =
1377 seg_info (data_section)->frchainP->frch_last;
1378 seg_info (data_section)->frchainP = 0;
1379 }
1380
1381 static void
1382 set_symtab (void)
1383 {
1384 int nsyms;
1385 asymbol **asympp;
1386 symbolS *symp;
1387 bfd_boolean result;
1388
1389 /* Count symbols. We can't rely on a count made by the loop in
1390 write_object_file, because *_frob_file may add a new symbol or
1391 two. */
1392 nsyms = 0;
1393 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1394 nsyms++;
1395
1396 if (nsyms)
1397 {
1398 int i;
1399 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1400
1401 asympp = bfd_alloc (stdoutput, amt);
1402 symp = symbol_rootP;
1403 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1404 {
1405 asympp[i] = symbol_get_bfdsym (symp);
1406 if (asympp[i]->flags != BSF_SECTION_SYM
1407 || !(bfd_is_const_section (asympp[i]->section)
1408 && asympp[i]->section->symbol == asympp[i]))
1409 asympp[i]->flags |= BSF_KEEP;
1410 symbol_mark_written (symp);
1411 }
1412 }
1413 else
1414 asympp = 0;
1415 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1416 gas_assert (result);
1417 symbol_table_frozen = 1;
1418 }
1419
1420 /* Finish the subsegments. After every sub-segment, we fake an
1421 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1422 ".fill 0" because that is the kind of frag that requires least
1423 thought. ".align" frags like to have a following frag since that
1424 makes calculating their intended length trivial. */
1425
1426 #ifndef SUB_SEGMENT_ALIGN
1427 #ifdef HANDLE_ALIGN
1428 /* The last subsegment gets an alignment corresponding to the alignment
1429 of the section. This allows proper nop-filling at the end of
1430 code-bearing sections. */
1431 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1432 (!(FRCHAIN)->frch_next ? get_recorded_alignment (SEG) : 0)
1433 #else
1434 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1435 #endif
1436 #endif
1437
1438 void
1439 subsegs_finish (void)
1440 {
1441 struct frchain *frchainP;
1442 asection *s;
1443
1444 for (s = stdoutput->sections; s; s = s->next)
1445 {
1446 segment_info_type *seginfo = seg_info (s);
1447 if (!seginfo)
1448 continue;
1449
1450 for (frchainP = seginfo->frchainP;
1451 frchainP != NULL;
1452 frchainP = frchainP->frch_next)
1453 {
1454 int alignment = 0;
1455
1456 subseg_set (s, frchainP->frch_subseg);
1457
1458 /* This now gets called even if we had errors. In that case,
1459 any alignment is meaningless, and, moreover, will look weird
1460 if we are generating a listing. */
1461 if (!had_errors ())
1462 {
1463 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1464 if ((bfd_get_section_flags (now_seg->owner, now_seg) & SEC_MERGE)
1465 && now_seg->entsize)
1466 {
1467 unsigned int entsize = now_seg->entsize;
1468 int entalign = 0;
1469
1470 while ((entsize & 1) == 0)
1471 {
1472 ++entalign;
1473 entsize >>= 1;
1474 }
1475 if (entalign > alignment)
1476 alignment = entalign;
1477 }
1478 }
1479
1480 if (subseg_text_p (now_seg))
1481 frag_align_code (alignment, 0);
1482 else
1483 frag_align (alignment, 0, 0);
1484
1485 /* frag_align will have left a new frag.
1486 Use this last frag for an empty ".fill".
1487
1488 For this segment ...
1489 Create a last frag. Do not leave a "being filled in frag". */
1490 frag_wane (frag_now);
1491 frag_now->fr_fix = 0;
1492 know (frag_now->fr_next == NULL);
1493 }
1494 }
1495 }
1496
1497 /* Write the object file. */
1498
1499 void
1500 write_object_file (void)
1501 {
1502 struct relax_seg_info rsi;
1503 #ifndef WORKING_DOT_WORD
1504 fragS *fragP; /* Track along all frags. */
1505 #endif
1506
1507 /* Do we really want to write it? */
1508 {
1509 int n_warns, n_errs;
1510 n_warns = had_warnings ();
1511 n_errs = had_errors ();
1512 /* The -Z flag indicates that an object file should be generated,
1513 regardless of warnings and errors. */
1514 if (flag_always_generate_output)
1515 {
1516 if (n_warns || n_errs)
1517 as_warn (_("%d error%s, %d warning%s, generating bad object file"),
1518 n_errs, n_errs == 1 ? "" : "s",
1519 n_warns, n_warns == 1 ? "" : "s");
1520 }
1521 else
1522 {
1523 if (n_errs)
1524 as_fatal (_("%d error%s, %d warning%s, no object file generated"),
1525 n_errs, n_errs == 1 ? "" : "s",
1526 n_warns, n_warns == 1 ? "" : "s");
1527 }
1528 }
1529
1530 #ifdef OBJ_VMS
1531 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1532 a routine to check for the definition of the procedure "_main",
1533 and if so -- fix it up so that it can be program entry point. */
1534 vms_check_for_main ();
1535 #endif /* OBJ_VMS */
1536
1537 /* From now on, we don't care about sub-segments. Build one frag chain
1538 for each segment. Linked thru fr_next. */
1539
1540 /* Remove the sections created by gas for its own purposes. */
1541 {
1542 int i;
1543
1544 bfd_section_list_remove (stdoutput, reg_section);
1545 bfd_section_list_remove (stdoutput, expr_section);
1546 stdoutput->section_count -= 2;
1547 i = 0;
1548 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1549 }
1550
1551 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1552
1553 /* We have two segments. If user gave -R flag, then we must put the
1554 data frags into the text segment. Do this before relaxing so
1555 we know to take advantage of -R and make shorter addresses. */
1556 if (flag_readonly_data_in_text)
1557 {
1558 merge_data_into_text ();
1559 }
1560
1561 rsi.pass = 0;
1562 while (1)
1563 {
1564 #ifndef WORKING_DOT_WORD
1565 /* We need to reset the markers in the broken word list and
1566 associated frags between calls to relax_segment (via
1567 relax_seg). Since the broken word list is global, we do it
1568 once per round, rather than locally in relax_segment for each
1569 segment. */
1570 struct broken_word *brokp;
1571
1572 for (brokp = broken_words;
1573 brokp != (struct broken_word *) NULL;
1574 brokp = brokp->next_broken_word)
1575 {
1576 brokp->added = 0;
1577
1578 if (brokp->dispfrag != (fragS *) NULL
1579 && brokp->dispfrag->fr_type == rs_broken_word)
1580 brokp->dispfrag->fr_subtype = 0;
1581 }
1582 #endif
1583
1584 rsi.changed = 0;
1585 bfd_map_over_sections (stdoutput, relax_seg, &rsi);
1586 rsi.pass++;
1587 if (!rsi.changed)
1588 break;
1589 }
1590
1591 /* Note - Most ports will use the default value of
1592 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
1593 local symbols to be resolved, removing their frag information.
1594 Some ports however, will not have finished relaxing all of
1595 their frags and will still need the local symbol frag
1596 information. These ports can set
1597 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
1598 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
1599
1600 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
1601
1602 /* Relaxation has completed. Freeze all syms. */
1603 finalize_syms = 1;
1604
1605 #ifdef md_post_relax_hook
1606 md_post_relax_hook;
1607 #endif
1608
1609 #ifndef WORKING_DOT_WORD
1610 {
1611 struct broken_word *lie;
1612 struct broken_word **prevP;
1613
1614 prevP = &broken_words;
1615 for (lie = broken_words; lie; lie = lie->next_broken_word)
1616 if (!lie->added)
1617 {
1618 expressionS exp;
1619
1620 subseg_change (lie->seg, lie->subseg);
1621 exp.X_op = O_subtract;
1622 exp.X_add_symbol = lie->add;
1623 exp.X_op_symbol = lie->sub;
1624 exp.X_add_number = lie->addnum;
1625 #ifdef TC_CONS_FIX_NEW
1626 TC_CONS_FIX_NEW (lie->frag,
1627 lie->word_goes_here - lie->frag->fr_literal,
1628 2, &exp);
1629 #else
1630 fix_new_exp (lie->frag,
1631 lie->word_goes_here - lie->frag->fr_literal,
1632 2, &exp, 0, BFD_RELOC_16);
1633 #endif
1634 *prevP = lie->next_broken_word;
1635 }
1636 else
1637 prevP = &(lie->next_broken_word);
1638
1639 for (lie = broken_words; lie;)
1640 {
1641 struct broken_word *untruth;
1642 char *table_ptr;
1643 addressT table_addr;
1644 addressT from_addr, to_addr;
1645 int n, m;
1646
1647 subseg_change (lie->seg, lie->subseg);
1648 fragP = lie->dispfrag;
1649
1650 /* Find out how many broken_words go here. */
1651 n = 0;
1652 for (untruth = lie;
1653 untruth && untruth->dispfrag == fragP;
1654 untruth = untruth->next_broken_word)
1655 if (untruth->added == 1)
1656 n++;
1657
1658 table_ptr = lie->dispfrag->fr_opcode;
1659 table_addr = (lie->dispfrag->fr_address
1660 + (table_ptr - lie->dispfrag->fr_literal));
1661 /* Create the jump around the long jumps. This is a short
1662 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1663 from_addr = table_addr;
1664 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1665 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1666 lie->add);
1667 table_ptr += md_short_jump_size;
1668 table_addr += md_short_jump_size;
1669
1670 for (m = 0;
1671 lie && lie->dispfrag == fragP;
1672 m++, lie = lie->next_broken_word)
1673 {
1674 if (lie->added == 2)
1675 continue;
1676 /* Patch the jump table. */
1677 for (untruth = (struct broken_word *) (fragP->fr_symbol);
1678 untruth && untruth->dispfrag == fragP;
1679 untruth = untruth->next_broken_word)
1680 {
1681 if (untruth->use_jump == lie)
1682 {
1683 /* This is the offset from ??? to table_ptr+0.
1684 The target is the same for all users of this
1685 md_long_jump, but the "sub" bases (and hence the
1686 offsets) may be different. */
1687 addressT to_word = table_addr - S_GET_VALUE (untruth->sub);
1688 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1689 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_word, untruth);
1690 #endif
1691 md_number_to_chars (untruth->word_goes_here, to_word, 2);
1692 }
1693 }
1694
1695 /* Install the long jump. */
1696 /* This is a long jump from table_ptr+0 to the final target. */
1697 from_addr = table_addr;
1698 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1699 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1700 lie->add);
1701 table_ptr += md_long_jump_size;
1702 table_addr += md_long_jump_size;
1703 }
1704 }
1705 }
1706 #endif /* not WORKING_DOT_WORD */
1707
1708 /* Resolve symbol values. This needs to be done before processing
1709 the relocations. */
1710 if (symbol_rootP)
1711 {
1712 symbolS *symp;
1713
1714 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1715 resolve_symbol_value (symp);
1716 }
1717 resolve_local_symbol_values ();
1718 resolve_reloc_expr_symbols ();
1719
1720 PROGRESS (1);
1721
1722 #ifdef tc_frob_file_before_adjust
1723 tc_frob_file_before_adjust ();
1724 #endif
1725 #ifdef obj_frob_file_before_adjust
1726 obj_frob_file_before_adjust ();
1727 #endif
1728
1729 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
1730
1731 #ifdef tc_frob_file_before_fix
1732 tc_frob_file_before_fix ();
1733 #endif
1734 #ifdef obj_frob_file_before_fix
1735 obj_frob_file_before_fix ();
1736 #endif
1737
1738 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
1739
1740 /* Set up symbol table, and write it out. */
1741 if (symbol_rootP)
1742 {
1743 symbolS *symp;
1744 bfd_boolean skip_next_symbol = FALSE;
1745
1746 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1747 {
1748 int punt = 0;
1749 const char *name;
1750
1751 if (skip_next_symbol)
1752 {
1753 /* Don't do anything besides moving the value of the
1754 symbol from the GAS value-field to the BFD value-field. */
1755 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1756 skip_next_symbol = FALSE;
1757 continue;
1758 }
1759
1760 if (symbol_mri_common_p (symp))
1761 {
1762 if (S_IS_EXTERNAL (symp))
1763 as_bad (_("%s: global symbols not supported in common sections"),
1764 S_GET_NAME (symp));
1765 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1766 continue;
1767 }
1768
1769 name = S_GET_NAME (symp);
1770 if (name)
1771 {
1772 const char *name2 =
1773 decode_local_label_name ((char *) S_GET_NAME (symp));
1774 /* They only differ if `name' is a fb or dollar local
1775 label name. */
1776 if (name2 != name && ! S_IS_DEFINED (symp))
1777 as_bad (_("local label `%s' is not defined"), name2);
1778 }
1779
1780 /* Do it again, because adjust_reloc_syms might introduce
1781 more symbols. They'll probably only be section symbols,
1782 but they'll still need to have the values computed. */
1783 resolve_symbol_value (symp);
1784
1785 /* Skip symbols which were equated to undefined or common
1786 symbols. */
1787 if (symbol_equated_reloc_p (symp)
1788 || S_IS_WEAKREFR (symp))
1789 {
1790 const char *name = S_GET_NAME (symp);
1791 if (S_IS_COMMON (symp)
1792 && !TC_FAKE_LABEL (name)
1793 && !S_IS_WEAKREFR (symp)
1794 && (!S_IS_EXTERNAL (symp) || S_IS_LOCAL (symp)))
1795 {
1796 expressionS *e = symbol_get_value_expression (symp);
1797 as_bad (_("Local symbol `%s' can't be equated to common symbol `%s'"),
1798 name, S_GET_NAME (e->X_add_symbol));
1799 }
1800 if (S_GET_SEGMENT (symp) == reg_section)
1801 {
1802 /* Report error only if we know the symbol name. */
1803 if (S_GET_NAME (symp) != reg_section->name)
1804 as_bad (_("can't make global register symbol `%s'"),
1805 name);
1806 }
1807 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1808 continue;
1809 }
1810
1811 #ifdef obj_frob_symbol
1812 obj_frob_symbol (symp, punt);
1813 #endif
1814 #ifdef tc_frob_symbol
1815 if (! punt || symbol_used_in_reloc_p (symp))
1816 tc_frob_symbol (symp, punt);
1817 #endif
1818
1819 /* If we don't want to keep this symbol, splice it out of
1820 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1821 want section symbols. Otherwise, we skip local symbols
1822 and symbols that the frob_symbol macros told us to punt,
1823 but we keep such symbols if they are used in relocs. */
1824 if (symp == abs_section_sym
1825 || (! EMIT_SECTION_SYMBOLS
1826 && symbol_section_p (symp))
1827 /* Note that S_IS_EXTERNAL and S_IS_LOCAL are not always
1828 opposites. Sometimes the former checks flags and the
1829 latter examines the name... */
1830 || (!S_IS_EXTERNAL (symp)
1831 && (punt || S_IS_LOCAL (symp) ||
1832 (S_IS_WEAKREFD (symp) && ! symbol_used_p (symp)))
1833 && ! symbol_used_in_reloc_p (symp)))
1834 {
1835 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1836
1837 /* After symbol_remove, symbol_next(symp) still returns
1838 the one that came after it in the chain. So we don't
1839 need to do any extra cleanup work here. */
1840 continue;
1841 }
1842
1843 /* Make sure we really got a value for the symbol. */
1844 if (! symbol_resolved_p (symp))
1845 {
1846 as_bad (_("can't resolve value for symbol `%s'"),
1847 S_GET_NAME (symp));
1848 symbol_mark_resolved (symp);
1849 }
1850
1851 /* Set the value into the BFD symbol. Up til now the value
1852 has only been kept in the gas symbolS struct. */
1853 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1854
1855 /* A warning construct is a warning symbol followed by the
1856 symbol warned about. Don't let anything object-format or
1857 target-specific muck with it; it's ready for output. */
1858 if (symbol_get_bfdsym (symp)->flags & BSF_WARNING)
1859 skip_next_symbol = TRUE;
1860 }
1861 }
1862
1863 PROGRESS (1);
1864
1865 /* Now do any format-specific adjustments to the symbol table, such
1866 as adding file symbols. */
1867 #ifdef tc_adjust_symtab
1868 tc_adjust_symtab ();
1869 #endif
1870 #ifdef obj_adjust_symtab
1871 obj_adjust_symtab ();
1872 #endif
1873
1874 /* Stop if there is an error. */
1875 if (had_errors ())
1876 return;
1877
1878 /* Now that all the sizes are known, and contents correct, we can
1879 start writing to the file. */
1880 set_symtab ();
1881
1882 /* If *_frob_file changes the symbol value at this point, it is
1883 responsible for moving the changed value into symp->bsym->value
1884 as well. Hopefully all symbol value changing can be done in
1885 *_frob_symbol. */
1886 #ifdef tc_frob_file
1887 tc_frob_file ();
1888 #endif
1889 #ifdef obj_frob_file
1890 obj_frob_file ();
1891 #endif
1892 #ifdef obj_coff_generate_pdata
1893 obj_coff_generate_pdata ();
1894 #endif
1895 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
1896
1897 #ifdef tc_frob_file_after_relocs
1898 tc_frob_file_after_relocs ();
1899 #endif
1900 #ifdef obj_frob_file_after_relocs
1901 obj_frob_file_after_relocs ();
1902 #endif
1903
1904 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
1905 }
1906
1907 #ifdef TC_GENERIC_RELAX_TABLE
1908 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
1909
1910 long
1911 relax_frag (segT segment, fragS *fragP, long stretch)
1912 {
1913 const relax_typeS *this_type;
1914 const relax_typeS *start_type;
1915 relax_substateT next_state;
1916 relax_substateT this_state;
1917 offsetT growth;
1918 offsetT aim;
1919 addressT target;
1920 addressT address;
1921 symbolS *symbolP;
1922 const relax_typeS *table;
1923
1924 target = fragP->fr_offset;
1925 address = fragP->fr_address;
1926 table = TC_GENERIC_RELAX_TABLE;
1927 this_state = fragP->fr_subtype;
1928 start_type = this_type = table + this_state;
1929 symbolP = fragP->fr_symbol;
1930
1931 if (symbolP)
1932 {
1933 fragS *sym_frag;
1934
1935 sym_frag = symbol_get_frag (symbolP);
1936
1937 #ifndef DIFF_EXPR_OK
1938 know (sym_frag != NULL);
1939 #endif
1940 know (S_GET_SEGMENT (symbolP) != absolute_section
1941 || sym_frag == &zero_address_frag);
1942 target += S_GET_VALUE (symbolP);
1943
1944 /* If frag has yet to be reached on this pass,
1945 assume it will move by STRETCH just as we did.
1946 If this is not so, it will be because some frag
1947 between grows, and that will force another pass. */
1948
1949 if (stretch != 0
1950 && sym_frag->relax_marker != fragP->relax_marker
1951 && S_GET_SEGMENT (symbolP) == segment)
1952 {
1953 target += stretch;
1954 }
1955 }
1956
1957 aim = target - address - fragP->fr_fix;
1958 #ifdef TC_PCREL_ADJUST
1959 /* Currently only the ns32k family needs this. */
1960 aim += TC_PCREL_ADJUST (fragP);
1961 #endif
1962
1963 #ifdef md_prepare_relax_scan
1964 /* Formerly called M68K_AIM_KLUDGE. */
1965 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
1966 #endif
1967
1968 if (aim < 0)
1969 {
1970 /* Look backwards. */
1971 for (next_state = this_type->rlx_more; next_state;)
1972 if (aim >= this_type->rlx_backward)
1973 next_state = 0;
1974 else
1975 {
1976 /* Grow to next state. */
1977 this_state = next_state;
1978 this_type = table + this_state;
1979 next_state = this_type->rlx_more;
1980 }
1981 }
1982 else
1983 {
1984 /* Look forwards. */
1985 for (next_state = this_type->rlx_more; next_state;)
1986 if (aim <= this_type->rlx_forward)
1987 next_state = 0;
1988 else
1989 {
1990 /* Grow to next state. */
1991 this_state = next_state;
1992 this_type = table + this_state;
1993 next_state = this_type->rlx_more;
1994 }
1995 }
1996
1997 growth = this_type->rlx_length - start_type->rlx_length;
1998 if (growth != 0)
1999 fragP->fr_subtype = this_state;
2000 return growth;
2001 }
2002
2003 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2004
2005 /* Relax_align. Advance location counter to next address that has 'alignment'
2006 lowest order bits all 0s, return size of adjustment made. */
2007 static relax_addressT
2008 relax_align (register relax_addressT address, /* Address now. */
2009 register int alignment /* Alignment (binary). */)
2010 {
2011 relax_addressT mask;
2012 relax_addressT new_address;
2013
2014 mask = ~((~0) << alignment);
2015 new_address = (address + mask) & (~mask);
2016 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2017 if (linkrelax)
2018 /* We must provide lots of padding, so the linker can discard it
2019 when needed. The linker will not add extra space, ever. */
2020 new_address += (1 << alignment);
2021 #endif
2022 return (new_address - address);
2023 }
2024
2025 /* Now we have a segment, not a crowd of sub-segments, we can make
2026 fr_address values.
2027
2028 Relax the frags.
2029
2030 After this, all frags in this segment have addresses that are correct
2031 within the segment. Since segments live in different file addresses,
2032 these frag addresses may not be the same as final object-file
2033 addresses. */
2034
2035 int
2036 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2037 {
2038 unsigned long frag_count;
2039 struct frag *fragP;
2040 relax_addressT address;
2041 int ret;
2042
2043 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2044 subseg_change (segment, 0);
2045
2046 /* For each frag in segment: count and store (a 1st guess of)
2047 fr_address. */
2048 address = 0;
2049 for (frag_count = 0, fragP = segment_frag_root;
2050 fragP;
2051 fragP = fragP->fr_next, frag_count ++)
2052 {
2053 fragP->relax_marker = 0;
2054 fragP->fr_address = address;
2055 address += fragP->fr_fix;
2056
2057 switch (fragP->fr_type)
2058 {
2059 case rs_fill:
2060 address += fragP->fr_offset * fragP->fr_var;
2061 break;
2062
2063 case rs_align:
2064 case rs_align_code:
2065 case rs_align_test:
2066 {
2067 addressT offset = relax_align (address, (int) fragP->fr_offset);
2068
2069 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2070 offset = 0;
2071
2072 if (offset % fragP->fr_var != 0)
2073 {
2074 as_bad_where (fragP->fr_file, fragP->fr_line,
2075 _("alignment padding (%lu bytes) not a multiple of %ld"),
2076 (unsigned long) offset, (long) fragP->fr_var);
2077 offset -= (offset % fragP->fr_var);
2078 }
2079
2080 address += offset;
2081 }
2082 break;
2083
2084 case rs_org:
2085 case rs_space:
2086 /* Assume .org is nugatory. It will grow with 1st relax. */
2087 break;
2088
2089 case rs_machine_dependent:
2090 /* If fr_symbol is an expression, this call to
2091 resolve_symbol_value sets up the correct segment, which will
2092 likely be needed in md_estimate_size_before_relax. */
2093 if (fragP->fr_symbol)
2094 resolve_symbol_value (fragP->fr_symbol);
2095
2096 address += md_estimate_size_before_relax (fragP, segment);
2097 break;
2098
2099 #ifndef WORKING_DOT_WORD
2100 /* Broken words don't concern us yet. */
2101 case rs_broken_word:
2102 break;
2103 #endif
2104
2105 case rs_leb128:
2106 /* Initial guess is always 1; doing otherwise can result in
2107 stable solutions that are larger than the minimum. */
2108 address += fragP->fr_offset = 1;
2109 break;
2110
2111 case rs_cfa:
2112 address += eh_frame_estimate_size_before_relax (fragP);
2113 break;
2114
2115 case rs_dwarf2dbg:
2116 address += dwarf2dbg_estimate_size_before_relax (fragP);
2117 break;
2118
2119 default:
2120 BAD_CASE (fragP->fr_type);
2121 break;
2122 }
2123 }
2124
2125 /* Do relax(). */
2126 {
2127 unsigned long max_iterations;
2128
2129 /* Cumulative address adjustment. */
2130 offsetT stretch;
2131
2132 /* Have we made any adjustment this pass? We can't just test
2133 stretch because one piece of code may have grown and another
2134 shrank. */
2135 int stretched;
2136
2137 /* Most horrible, but gcc may give us some exception data that
2138 is impossible to assemble, of the form
2139
2140 .align 4
2141 .byte 0, 0
2142 .uleb128 end - start
2143 start:
2144 .space 128*128 - 1
2145 .align 4
2146 end:
2147
2148 If the leb128 is two bytes in size, then end-start is 128*128,
2149 which requires a three byte leb128. If the leb128 is three
2150 bytes in size, then end-start is 128*128-1, which requires a
2151 two byte leb128. We work around this dilemma by inserting
2152 an extra 4 bytes of alignment just after the .align. This
2153 works because the data after the align is accessed relative to
2154 the end label.
2155
2156 This counter is used in a tiny state machine to detect
2157 whether a leb128 followed by an align is impossible to
2158 relax. */
2159 int rs_leb128_fudge = 0;
2160
2161 /* We want to prevent going into an infinite loop where one frag grows
2162 depending upon the location of a symbol which is in turn moved by
2163 the growing frag. eg:
2164
2165 foo = .
2166 .org foo+16
2167 foo = .
2168
2169 So we dictate that this algorithm can be at most O2. */
2170 max_iterations = frag_count * frag_count;
2171 /* Check for overflow. */
2172 if (max_iterations < frag_count)
2173 max_iterations = frag_count;
2174
2175 ret = 0;
2176 do
2177 {
2178 stretch = 0;
2179 stretched = 0;
2180
2181 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2182 {
2183 offsetT growth = 0;
2184 addressT was_address;
2185 offsetT offset;
2186 symbolS *symbolP;
2187
2188 fragP->relax_marker ^= 1;
2189 was_address = fragP->fr_address;
2190 address = fragP->fr_address += stretch;
2191 symbolP = fragP->fr_symbol;
2192 offset = fragP->fr_offset;
2193
2194 switch (fragP->fr_type)
2195 {
2196 case rs_fill: /* .fill never relaxes. */
2197 growth = 0;
2198 break;
2199
2200 #ifndef WORKING_DOT_WORD
2201 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2202 for it I do not want to write it. I do not want to have
2203 anything to do with it. This is not the proper way to
2204 implement this misfeature. */
2205 case rs_broken_word:
2206 {
2207 struct broken_word *lie;
2208 struct broken_word *untruth;
2209
2210 /* Yes this is ugly (storing the broken_word pointer
2211 in the symbol slot). Still, this whole chunk of
2212 code is ugly, and I don't feel like doing anything
2213 about it. Think of it as stubbornness in action. */
2214 growth = 0;
2215 for (lie = (struct broken_word *) (fragP->fr_symbol);
2216 lie && lie->dispfrag == fragP;
2217 lie = lie->next_broken_word)
2218 {
2219
2220 if (lie->added)
2221 continue;
2222
2223 offset = (S_GET_VALUE (lie->add)
2224 + lie->addnum
2225 - S_GET_VALUE (lie->sub));
2226 if (offset <= -32768 || offset >= 32767)
2227 {
2228 if (flag_warn_displacement)
2229 {
2230 char buf[50];
2231 sprint_value (buf, (addressT) lie->addnum);
2232 as_warn_where (fragP->fr_file, fragP->fr_line,
2233 _(".word %s-%s+%s didn't fit"),
2234 S_GET_NAME (lie->add),
2235 S_GET_NAME (lie->sub),
2236 buf);
2237 }
2238 if (fragP->fr_subtype == 0)
2239 {
2240 fragP->fr_subtype++;
2241 growth += md_short_jump_size;
2242 }
2243
2244 /* Redirect *all* words of this table with the same
2245 target, lest we have to handle the case where the
2246 same target but with a offset that fits on this
2247 round overflows at the next relaxation round. */
2248 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2249 untruth && untruth->dispfrag == lie->dispfrag;
2250 untruth = untruth->next_broken_word)
2251 if ((symbol_get_frag (untruth->add)
2252 == symbol_get_frag (lie->add))
2253 && (S_GET_VALUE (untruth->add)
2254 == S_GET_VALUE (lie->add)))
2255 {
2256 untruth->added = 2;
2257 untruth->use_jump = lie;
2258 }
2259
2260 lie->added = 1;
2261 growth += md_long_jump_size;
2262 }
2263 }
2264
2265 break;
2266 } /* case rs_broken_word */
2267 #endif
2268 case rs_align:
2269 case rs_align_code:
2270 case rs_align_test:
2271 {
2272 addressT oldoff, newoff;
2273
2274 oldoff = relax_align (was_address + fragP->fr_fix,
2275 (int) offset);
2276 newoff = relax_align (address + fragP->fr_fix,
2277 (int) offset);
2278
2279 if (fragP->fr_subtype != 0)
2280 {
2281 if (oldoff > fragP->fr_subtype)
2282 oldoff = 0;
2283 if (newoff > fragP->fr_subtype)
2284 newoff = 0;
2285 }
2286
2287 growth = newoff - oldoff;
2288
2289 /* If this align happens to follow a leb128 and
2290 we have determined that the leb128 is bouncing
2291 in size, then break the cycle by inserting an
2292 extra alignment. */
2293 if (growth < 0
2294 && (rs_leb128_fudge & 16) != 0
2295 && (rs_leb128_fudge & 15) >= 2)
2296 {
2297 segment_info_type *seginfo = seg_info (segment);
2298 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2299 struct frag *newf;
2300
2301 newf = frag_alloc (ob);
2302 obstack_blank_fast (ob, fragP->fr_var);
2303 obstack_finish (ob);
2304 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2305 memcpy (newf->fr_literal,
2306 fragP->fr_literal + fragP->fr_fix,
2307 fragP->fr_var);
2308 newf->fr_type = rs_fill;
2309 newf->fr_fix = 0;
2310 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2311 / fragP->fr_var);
2312 if (newf->fr_offset * newf->fr_var
2313 != (offsetT) 1 << fragP->fr_offset)
2314 {
2315 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2316 newf->fr_var = 1;
2317 }
2318 /* Include growth of new frag, because rs_fill
2319 frags don't normally grow. */
2320 growth += newf->fr_offset * newf->fr_var;
2321 /* The new frag address is newoff. Adjust this
2322 for the amount we'll add when we process the
2323 new frag. */
2324 newf->fr_address = newoff - stretch - growth;
2325 newf->relax_marker ^= 1;
2326 fragP->fr_next = newf;
2327 #ifdef DEBUG
2328 as_warn (_("padding added"));
2329 #endif
2330 }
2331 }
2332 break;
2333
2334 case rs_org:
2335 {
2336 addressT target = offset;
2337 addressT after;
2338
2339 if (symbolP)
2340 {
2341 /* Convert from an actual address to an octet offset
2342 into the section. Here it is assumed that the
2343 section's VMA is zero, and can omit subtracting it
2344 from the symbol's value to get the address offset. */
2345 know (S_GET_SEGMENT (symbolP)->vma == 0);
2346 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2347 }
2348
2349 know (fragP->fr_next);
2350 after = fragP->fr_next->fr_address + stretch;
2351 growth = target - after;
2352 if (growth < 0)
2353 {
2354 growth = 0;
2355
2356 /* Don't error on first few frag relax passes.
2357 The symbol might be an expression involving
2358 symbol values from other sections. If those
2359 sections have not yet been processed their
2360 frags will all have zero addresses, so we
2361 will calculate incorrect values for them. The
2362 number of passes we allow before giving an
2363 error is somewhat arbitrary. It should be at
2364 least one, with larger values requiring
2365 increasingly contrived dependencies between
2366 frags to trigger a false error. */
2367 if (pass < 2)
2368 {
2369 /* Force another pass. */
2370 ret = 1;
2371 break;
2372 }
2373
2374 /* Growth may be negative, but variable part of frag
2375 cannot have fewer than 0 chars. That is, we can't
2376 .org backwards. */
2377 as_bad_where (fragP->fr_file, fragP->fr_line,
2378 _("attempt to move .org backwards"));
2379
2380 /* We've issued an error message. Change the
2381 frag to avoid cascading errors. */
2382 fragP->fr_type = rs_align;
2383 fragP->fr_subtype = 0;
2384 fragP->fr_offset = 0;
2385 fragP->fr_fix = after - address;
2386 }
2387 }
2388 break;
2389
2390 case rs_space:
2391 growth = 0;
2392 if (symbolP)
2393 {
2394 offsetT amount;
2395
2396 amount = S_GET_VALUE (symbolP);
2397 if (S_GET_SEGMENT (symbolP) != absolute_section
2398 || S_IS_COMMON (symbolP)
2399 || ! S_IS_DEFINED (symbolP))
2400 {
2401 as_bad_where (fragP->fr_file, fragP->fr_line,
2402 _(".space specifies non-absolute value"));
2403 /* Prevent repeat of this error message. */
2404 fragP->fr_symbol = 0;
2405 }
2406 else if (amount < 0)
2407 {
2408 /* Don't error on first few frag relax passes.
2409 See rs_org comment for a longer explanation. */
2410 if (pass < 2)
2411 {
2412 ret = 1;
2413 break;
2414 }
2415
2416 as_warn_where (fragP->fr_file, fragP->fr_line,
2417 _(".space or .fill with negative value, ignored"));
2418 fragP->fr_symbol = 0;
2419 }
2420 else
2421 growth = (was_address + fragP->fr_fix + amount
2422 - fragP->fr_next->fr_address);
2423 }
2424 break;
2425
2426 case rs_machine_dependent:
2427 #ifdef md_relax_frag
2428 growth = md_relax_frag (segment, fragP, stretch);
2429 #else
2430 #ifdef TC_GENERIC_RELAX_TABLE
2431 /* The default way to relax a frag is to look through
2432 TC_GENERIC_RELAX_TABLE. */
2433 growth = relax_frag (segment, fragP, stretch);
2434 #endif /* TC_GENERIC_RELAX_TABLE */
2435 #endif
2436 break;
2437
2438 case rs_leb128:
2439 {
2440 valueT value;
2441 offsetT size;
2442
2443 value = resolve_symbol_value (fragP->fr_symbol);
2444 size = sizeof_leb128 (value, fragP->fr_subtype);
2445 growth = size - fragP->fr_offset;
2446 fragP->fr_offset = size;
2447 }
2448 break;
2449
2450 case rs_cfa:
2451 growth = eh_frame_relax_frag (fragP);
2452 break;
2453
2454 case rs_dwarf2dbg:
2455 growth = dwarf2dbg_relax_frag (fragP);
2456 break;
2457
2458 default:
2459 BAD_CASE (fragP->fr_type);
2460 break;
2461 }
2462 if (growth)
2463 {
2464 stretch += growth;
2465 stretched = 1;
2466 if (fragP->fr_type == rs_leb128)
2467 rs_leb128_fudge += 16;
2468 else if (fragP->fr_type == rs_align
2469 && (rs_leb128_fudge & 16) != 0
2470 && stretch == 0)
2471 rs_leb128_fudge += 16;
2472 else
2473 rs_leb128_fudge = 0;
2474 }
2475 }
2476
2477 if (stretch == 0
2478 && (rs_leb128_fudge & 16) == 0
2479 && (rs_leb128_fudge & -16) != 0)
2480 rs_leb128_fudge += 1;
2481 else
2482 rs_leb128_fudge = 0;
2483 }
2484 /* Until nothing further to relax. */
2485 while (stretched && -- max_iterations);
2486
2487 if (stretched)
2488 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
2489 segment_name (segment));
2490 }
2491
2492 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2493 if (fragP->last_fr_address != fragP->fr_address)
2494 {
2495 fragP->last_fr_address = fragP->fr_address;
2496 ret = 1;
2497 }
2498 return ret;
2499 }
2500
2501 void
2502 number_to_chars_bigendian (char *buf, valueT val, int n)
2503 {
2504 if (n <= 0)
2505 abort ();
2506 while (n--)
2507 {
2508 buf[n] = val & 0xff;
2509 val >>= 8;
2510 }
2511 }
2512
2513 void
2514 number_to_chars_littleendian (char *buf, valueT val, int n)
2515 {
2516 if (n <= 0)
2517 abort ();
2518 while (n--)
2519 {
2520 *buf++ = val & 0xff;
2521 val >>= 8;
2522 }
2523 }
2524
2525 void
2526 write_print_statistics (FILE *file)
2527 {
2528 fprintf (file, "fixups: %d\n", n_fixups);
2529 }
2530
2531 /* For debugging. */
2532 extern int indent_level;
2533
2534 void
2535 print_fixup (fixS *fixp)
2536 {
2537 indent_level = 1;
2538 fprintf (stderr, "fix ");
2539 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
2540 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
2541 if (fixp->fx_pcrel)
2542 fprintf (stderr, " pcrel");
2543 if (fixp->fx_pcrel_adjust)
2544 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2545 if (fixp->fx_im_disp)
2546 {
2547 #ifdef TC_NS32K
2548 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2549 #else
2550 fprintf (stderr, " im_disp");
2551 #endif
2552 }
2553 if (fixp->fx_tcbit)
2554 fprintf (stderr, " tcbit");
2555 if (fixp->fx_done)
2556 fprintf (stderr, " done");
2557 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
2558 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
2559 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
2560 (long) fixp->fx_where,
2561 (unsigned long) fixp->fx_offset,
2562 (unsigned long) fixp->fx_addnumber);
2563 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2564 fixp->fx_r_type);
2565 if (fixp->fx_addsy)
2566 {
2567 fprintf (stderr, "\n +<");
2568 print_symbol_value_1 (stderr, fixp->fx_addsy);
2569 fprintf (stderr, ">");
2570 }
2571 if (fixp->fx_subsy)
2572 {
2573 fprintf (stderr, "\n -<");
2574 print_symbol_value_1 (stderr, fixp->fx_subsy);
2575 fprintf (stderr, ">");
2576 }
2577 fprintf (stderr, "\n");
2578 #ifdef TC_FIX_DATA_PRINT
2579 TC_FIX_DATA_PRINT (stderr, fixp);
2580 #endif
2581 }
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