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1 /* write.c - emit .o file
2 Copyright (C) 1986-2018 Free Software Foundation, Inc.
3
4 This file is part of GAS, the GNU Assembler.
5
6 GAS is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10
11 GAS is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GAS; see the file COPYING. If not, write to the Free
18 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
19 02110-1301, USA. */
20
21 /* This thing should be set up to do byte ordering correctly. But... */
22
23 #include "as.h"
24 #include "subsegs.h"
25 #include "obstack.h"
26 #include "output-file.h"
27 #include "dwarf2dbg.h"
28 #include "compress-debug.h"
29
30 #ifndef TC_FORCE_RELOCATION
31 #define TC_FORCE_RELOCATION(FIX) \
32 (generic_force_reloc (FIX))
33 #endif
34
35 #ifndef TC_FORCE_RELOCATION_ABS
36 #define TC_FORCE_RELOCATION_ABS(FIX) \
37 (TC_FORCE_RELOCATION (FIX))
38 #endif
39
40 #define GENERIC_FORCE_RELOCATION_LOCAL(FIX) \
41 (!(FIX)->fx_pcrel \
42 || TC_FORCE_RELOCATION (FIX))
43 #ifndef TC_FORCE_RELOCATION_LOCAL
44 #define TC_FORCE_RELOCATION_LOCAL GENERIC_FORCE_RELOCATION_LOCAL
45 #endif
46
47 #define GENERIC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
48 (!SEG_NORMAL (SEG))
49 #ifndef TC_FORCE_RELOCATION_SUB_SAME
50 #define TC_FORCE_RELOCATION_SUB_SAME GENERIC_FORCE_RELOCATION_SUB_SAME
51 #endif
52
53 #ifndef md_register_arithmetic
54 # define md_register_arithmetic 1
55 #endif
56
57 #ifndef TC_FORCE_RELOCATION_SUB_ABS
58 #define TC_FORCE_RELOCATION_SUB_ABS(FIX, SEG) \
59 (!md_register_arithmetic && (SEG) == reg_section)
60 #endif
61
62 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
63 #ifdef DIFF_EXPR_OK
64 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) \
65 (!md_register_arithmetic && (SEG) == reg_section)
66 #else
67 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) 1
68 #endif
69 #endif
70
71 #ifndef TC_VALIDATE_FIX_SUB
72 #ifdef UNDEFINED_DIFFERENCE_OK
73 /* The PA needs this for PIC code generation. */
74 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
75 (md_register_arithmetic || (SEG) != reg_section)
76 #else
77 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
78 ((md_register_arithmetic || (SEG) != reg_section) \
79 && ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
80 || (FIX)->fx_r_type == BFD_RELOC_GPREL16))
81 #endif
82 #endif
83
84 #ifndef TC_LINKRELAX_FIXUP
85 #define TC_LINKRELAX_FIXUP(SEG) 1
86 #endif
87
88 #ifndef MD_APPLY_SYM_VALUE
89 #define MD_APPLY_SYM_VALUE(FIX) 1
90 #endif
91
92 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
93 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
94 #endif
95
96 #ifndef MD_PCREL_FROM_SECTION
97 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
98 #endif
99
100 #ifndef TC_FAKE_LABEL
101 #define TC_FAKE_LABEL(NAME) (strcmp ((NAME), FAKE_LABEL_NAME) == 0)
102 #endif
103
104 /* Positive values of TC_FX_SIZE_SLACK allow a target to define
105 fixups that far past the end of a frag. Having such fixups
106 is of course most most likely a bug in setting fx_size correctly.
107 A negative value disables the fixup check entirely, which is
108 appropriate for something like the Renesas / SuperH SH_COUNT
109 reloc. */
110 #ifndef TC_FX_SIZE_SLACK
111 #define TC_FX_SIZE_SLACK(FIX) 0
112 #endif
113
114 /* Used to control final evaluation of expressions. */
115 int finalize_syms = 0;
116
117 int symbol_table_frozen;
118
119 symbolS *abs_section_sym;
120
121 /* Remember the value of dot when parsing expressions. */
122 addressT dot_value;
123
124 /* The frag that dot_value is based from. */
125 fragS *dot_frag;
126
127 /* Relocs generated by ".reloc" pseudo. */
128 struct reloc_list* reloc_list;
129
130 void print_fixup (fixS *);
131
132 /* We generally attach relocs to frag chains. However, after we have
133 chained these all together into a segment, any relocs we add after
134 that must be attached to a segment. This will include relocs added
135 in md_estimate_size_for_relax, for example. */
136 static int frags_chained = 0;
137
138 static int n_fixups;
139
140 #define RELOC_ENUM enum bfd_reloc_code_real
141
142 /* Create a fixS in obstack 'notes'. */
143
144 static fixS *
145 fix_new_internal (fragS *frag, /* Which frag? */
146 int where, /* Where in that frag? */
147 int size, /* 1, 2, or 4 usually. */
148 symbolS *add_symbol, /* X_add_symbol. */
149 symbolS *sub_symbol, /* X_op_symbol. */
150 offsetT offset, /* X_add_number. */
151 int pcrel, /* TRUE if PC-relative relocation. */
152 RELOC_ENUM r_type /* Relocation type. */,
153 int at_beginning) /* Add to the start of the list? */
154 {
155 fixS *fixP;
156
157 n_fixups++;
158
159 fixP = (fixS *) 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_dot_frag = dot_frag;
175 fixP->fx_pcrel = pcrel;
176 fixP->fx_r_type = r_type;
177 fixP->fx_im_disp = 0;
178 fixP->fx_pcrel_adjust = 0;
179 fixP->fx_bit_fixP = 0;
180 fixP->fx_addnumber = 0;
181 fixP->fx_tcbit = 0;
182 fixP->fx_tcbit2 = 0;
183 fixP->fx_done = 0;
184 fixP->fx_no_overflow = 0;
185 fixP->fx_signed = 0;
186
187 #ifdef USING_CGEN
188 fixP->fx_cgen.insn = NULL;
189 fixP->fx_cgen.opinfo = 0;
190 #endif
191
192 #ifdef TC_FIX_TYPE
193 TC_INIT_FIX_DATA (fixP);
194 #endif
195
196 fixP->fx_file = as_where (&fixP->fx_line);
197
198 {
199
200 fixS **seg_fix_rootP = (frags_chained
201 ? &seg_info (now_seg)->fix_root
202 : &frchain_now->fix_root);
203 fixS **seg_fix_tailP = (frags_chained
204 ? &seg_info (now_seg)->fix_tail
205 : &frchain_now->fix_tail);
206
207 if (at_beginning)
208 {
209 fixP->fx_next = *seg_fix_rootP;
210 *seg_fix_rootP = fixP;
211 if (fixP->fx_next == NULL)
212 *seg_fix_tailP = fixP;
213 }
214 else
215 {
216 fixP->fx_next = NULL;
217 if (*seg_fix_tailP)
218 (*seg_fix_tailP)->fx_next = fixP;
219 else
220 *seg_fix_rootP = fixP;
221 *seg_fix_tailP = fixP;
222 }
223 }
224
225 return fixP;
226 }
227
228 /* Create a fixup relative to a symbol (plus a constant). */
229
230 fixS *
231 fix_new (fragS *frag, /* Which frag? */
232 int where, /* Where in that frag? */
233 int size, /* 1, 2, or 4 usually. */
234 symbolS *add_symbol, /* X_add_symbol. */
235 offsetT offset, /* X_add_number. */
236 int pcrel, /* TRUE if PC-relative relocation. */
237 RELOC_ENUM r_type /* Relocation type. */)
238 {
239 return fix_new_internal (frag, where, size, add_symbol,
240 (symbolS *) NULL, offset, pcrel, r_type, FALSE);
241 }
242
243 /* Create a fixup for an expression. Currently we only support fixups
244 for difference expressions. That is itself more than most object
245 file formats support anyhow. */
246
247 fixS *
248 fix_new_exp (fragS *frag, /* Which frag? */
249 int where, /* Where in that frag? */
250 int size, /* 1, 2, or 4 usually. */
251 expressionS *exp, /* Expression. */
252 int pcrel, /* TRUE if PC-relative relocation. */
253 RELOC_ENUM r_type /* Relocation type. */)
254 {
255 symbolS *add = NULL;
256 symbolS *sub = NULL;
257 offsetT off = 0;
258
259 switch (exp->X_op)
260 {
261 case O_absent:
262 break;
263
264 case O_register:
265 as_bad (_("register value used as expression"));
266 break;
267
268 case O_add:
269 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
270 the difference expression cannot immediately be reduced. */
271 {
272 symbolS *stmp = make_expr_symbol (exp);
273
274 exp->X_op = O_symbol;
275 exp->X_op_symbol = 0;
276 exp->X_add_symbol = stmp;
277 exp->X_add_number = 0;
278
279 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
280 }
281
282 case O_symbol_rva:
283 add = exp->X_add_symbol;
284 off = exp->X_add_number;
285 r_type = BFD_RELOC_RVA;
286 break;
287
288 case O_uminus:
289 sub = exp->X_add_symbol;
290 off = exp->X_add_number;
291 break;
292
293 case O_subtract:
294 sub = exp->X_op_symbol;
295 /* Fall through. */
296 case O_symbol:
297 add = exp->X_add_symbol;
298 /* Fall through. */
299 case O_constant:
300 off = exp->X_add_number;
301 break;
302
303 default:
304 add = make_expr_symbol (exp);
305 break;
306 }
307
308 return fix_new_internal (frag, where, size, add, sub, off, pcrel,
309 r_type, FALSE);
310 }
311
312 /* Create a fixup at the beginning of FRAG. The arguments are the same
313 as for fix_new, except that WHERE is implicitly 0. */
314
315 fixS *
316 fix_at_start (fragS *frag, int size, symbolS *add_symbol,
317 offsetT offset, int pcrel, RELOC_ENUM r_type)
318 {
319 return fix_new_internal (frag, 0, size, add_symbol,
320 (symbolS *) NULL, offset, pcrel, r_type, TRUE);
321 }
322
323 /* Generic function to determine whether a fixup requires a relocation. */
324 int
325 generic_force_reloc (fixS *fix)
326 {
327 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
328 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
329 return 1;
330
331 if (fix->fx_addsy == NULL)
332 return 0;
333
334 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
335 }
336
337 /* Append a string onto another string, bumping the pointer along. */
338 void
339 append (char **charPP, char *fromP, unsigned long length)
340 {
341 /* Don't trust memcpy() of 0 chars. */
342 if (length == 0)
343 return;
344
345 memcpy (*charPP, fromP, length);
346 *charPP += length;
347 }
348
349 /* This routine records the largest alignment seen for each segment.
350 If the beginning of the segment is aligned on the worst-case
351 boundary, all of the other alignments within it will work. At
352 least one object format really uses this info. */
353
354 void
355 record_alignment (/* Segment to which alignment pertains. */
356 segT seg,
357 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
358 boundary, 2 => 4-byte boundary, etc.) */
359 unsigned int align)
360 {
361 if (seg == absolute_section)
362 return;
363
364 if (align > bfd_get_section_alignment (stdoutput, seg))
365 bfd_set_section_alignment (stdoutput, seg, align);
366 }
367
368 int
369 get_recorded_alignment (segT seg)
370 {
371 if (seg == absolute_section)
372 return 0;
373
374 return bfd_get_section_alignment (stdoutput, seg);
375 }
376
377 /* Reset the section indices after removing the gas created sections. */
378
379 static void
380 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *countparg)
381 {
382 int *countp = (int *) countparg;
383
384 sec->index = *countp;
385 ++*countp;
386 }
387
388 static fragS *
389 chain_frchains_together_1 (segT section, struct frchain *frchp)
390 {
391 fragS dummy, *prev_frag = &dummy;
392 fixS fix_dummy, *prev_fix = &fix_dummy;
393
394 for (; frchp; frchp = frchp->frch_next)
395 {
396 prev_frag->fr_next = frchp->frch_root;
397 prev_frag = frchp->frch_last;
398 gas_assert (prev_frag->fr_type != 0);
399 if (frchp->fix_root != (fixS *) NULL)
400 {
401 if (seg_info (section)->fix_root == (fixS *) NULL)
402 seg_info (section)->fix_root = frchp->fix_root;
403 prev_fix->fx_next = frchp->fix_root;
404 seg_info (section)->fix_tail = frchp->fix_tail;
405 prev_fix = frchp->fix_tail;
406 }
407 }
408 gas_assert (prev_frag != &dummy
409 && prev_frag->fr_type != 0);
410 prev_frag->fr_next = 0;
411 return prev_frag;
412 }
413
414 static void
415 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
416 segT section,
417 void *xxx ATTRIBUTE_UNUSED)
418 {
419 segment_info_type *info;
420
421 /* BFD may have introduced its own sections without using
422 subseg_new, so it is possible that seg_info is NULL. */
423 info = seg_info (section);
424 if (info != (segment_info_type *) NULL)
425 info->frchainP->frch_last
426 = chain_frchains_together_1 (section, info->frchainP);
427
428 /* Now that we've chained the frags together, we must add new fixups
429 to the segment, not to the frag chain. */
430 frags_chained = 1;
431 }
432
433 static void
434 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
435 {
436 switch (fragP->fr_type)
437 {
438 case rs_space_nop:
439 goto skip_align;
440 case rs_align:
441 case rs_align_code:
442 case rs_align_test:
443 case rs_org:
444 case rs_space:
445 #ifdef HANDLE_ALIGN
446 HANDLE_ALIGN (fragP);
447 #endif
448 skip_align:
449 know (fragP->fr_next != NULL);
450 fragP->fr_offset = (fragP->fr_next->fr_address
451 - fragP->fr_address
452 - fragP->fr_fix) / fragP->fr_var;
453 if (fragP->fr_offset < 0)
454 {
455 as_bad_where (fragP->fr_file, fragP->fr_line,
456 _("attempt to .org/.space/.nops backwards? (%ld)"),
457 (long) fragP->fr_offset);
458 fragP->fr_offset = 0;
459 }
460 if (fragP->fr_type == rs_space_nop)
461 fragP->fr_type = rs_fill_nop;
462 else
463 fragP->fr_type = rs_fill;
464 break;
465
466 case rs_fill:
467 case rs_fill_nop:
468 break;
469
470 case rs_leb128:
471 {
472 valueT value = S_GET_VALUE (fragP->fr_symbol);
473 int size;
474
475 if (!S_IS_DEFINED (fragP->fr_symbol))
476 {
477 as_bad_where (fragP->fr_file, fragP->fr_line,
478 _("leb128 operand is an undefined symbol: %s"),
479 S_GET_NAME (fragP->fr_symbol));
480 }
481
482 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
483 fragP->fr_subtype);
484
485 fragP->fr_fix += size;
486 fragP->fr_type = rs_fill;
487 fragP->fr_var = 0;
488 fragP->fr_offset = 0;
489 fragP->fr_symbol = NULL;
490 }
491 break;
492
493 case rs_cfa:
494 eh_frame_convert_frag (fragP);
495 break;
496
497 case rs_dwarf2dbg:
498 dwarf2dbg_convert_frag (fragP);
499 break;
500
501 case rs_machine_dependent:
502 md_convert_frag (stdoutput, sec, fragP);
503
504 gas_assert (fragP->fr_next == NULL
505 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
506 == fragP->fr_fix));
507
508 /* After md_convert_frag, we make the frag into a ".space 0".
509 md_convert_frag() should set up any fixSs and constants
510 required. */
511 frag_wane (fragP);
512 break;
513
514 #ifndef WORKING_DOT_WORD
515 case rs_broken_word:
516 {
517 struct broken_word *lie;
518
519 if (fragP->fr_subtype)
520 {
521 fragP->fr_fix += md_short_jump_size;
522 for (lie = (struct broken_word *) (fragP->fr_symbol);
523 lie && lie->dispfrag == fragP;
524 lie = lie->next_broken_word)
525 if (lie->added == 1)
526 fragP->fr_fix += md_long_jump_size;
527 }
528 frag_wane (fragP);
529 }
530 break;
531 #endif
532
533 default:
534 BAD_CASE (fragP->fr_type);
535 break;
536 }
537 #ifdef md_frag_check
538 md_frag_check (fragP);
539 #endif
540 }
541
542 struct relax_seg_info
543 {
544 int pass;
545 int changed;
546 };
547
548 static void
549 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx)
550 {
551 segment_info_type *seginfo = seg_info (sec);
552 struct relax_seg_info *info = (struct relax_seg_info *) xxx;
553
554 if (seginfo && seginfo->frchainP
555 && relax_segment (seginfo->frchainP->frch_root, sec, info->pass))
556 info->changed = 1;
557 }
558
559 static void
560 size_seg (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
561 {
562 flagword flags;
563 fragS *fragp;
564 segment_info_type *seginfo;
565 int x;
566 valueT size, newsize;
567
568 subseg_change (sec, 0);
569
570 seginfo = seg_info (sec);
571 if (seginfo && seginfo->frchainP)
572 {
573 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
574 cvt_frag_to_fill (sec, fragp);
575 for (fragp = seginfo->frchainP->frch_root;
576 fragp->fr_next;
577 fragp = fragp->fr_next)
578 /* Walk to last elt. */
579 ;
580 size = fragp->fr_address + fragp->fr_fix;
581 }
582 else
583 size = 0;
584
585 flags = bfd_get_section_flags (abfd, sec);
586 if (size == 0 && bfd_get_section_size (sec) != 0 &&
587 (flags & SEC_HAS_CONTENTS) != 0)
588 return;
589
590 if (size > 0 && ! seginfo->bss)
591 flags |= SEC_HAS_CONTENTS;
592
593 flags &= ~SEC_RELOC;
594 x = bfd_set_section_flags (abfd, sec, flags);
595 gas_assert (x);
596
597 /* If permitted, allow the backend to pad out the section
598 to some alignment boundary. */
599 if (do_not_pad_sections_to_alignment)
600 newsize = size;
601 else
602 newsize = md_section_align (sec, size);
603 x = bfd_set_section_size (abfd, sec, newsize);
604 gas_assert (x);
605
606 /* If the size had to be rounded up, add some padding in the last
607 non-empty frag. */
608 gas_assert (newsize >= size);
609 if (size != newsize)
610 {
611 fragS *last = seginfo->frchainP->frch_last;
612 fragp = seginfo->frchainP->frch_root;
613 while (fragp->fr_next != last)
614 fragp = fragp->fr_next;
615 last->fr_address = size;
616 if ((newsize - size) % fragp->fr_var == 0)
617 fragp->fr_offset += (newsize - size) / fragp->fr_var;
618 else
619 /* If we hit this abort, it's likely due to subsegs_finish not
620 providing sufficient alignment on the last frag, and the
621 machine dependent code using alignment frags with fr_var
622 greater than 1. */
623 abort ();
624 }
625
626 #ifdef tc_frob_section
627 tc_frob_section (sec);
628 #endif
629 #ifdef obj_frob_section
630 obj_frob_section (sec);
631 #endif
632 }
633
634 #ifdef DEBUG2
635 static void
636 dump_section_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, FILE *stream)
637 {
638 segment_info_type *seginfo = seg_info (sec);
639 fixS *fixp = seginfo->fix_root;
640
641 if (!fixp)
642 return;
643
644 fprintf (stream, "sec %s relocs:\n", sec->name);
645 while (fixp)
646 {
647 symbolS *s = fixp->fx_addsy;
648
649 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
650 (int) fixp->fx_r_type);
651 if (s == NULL)
652 fprintf (stream, "no sym\n");
653 else
654 {
655 print_symbol_value_1 (stream, s);
656 fprintf (stream, "\n");
657 }
658 fixp = fixp->fx_next;
659 }
660 }
661 #else
662 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
663 #endif
664
665 #ifndef EMIT_SECTION_SYMBOLS
666 #define EMIT_SECTION_SYMBOLS 1
667 #endif
668
669 /* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
670 and check for validity. Convert RELOC_LIST from using U.A fields
671 to U.B fields. */
672 static void
673 resolve_reloc_expr_symbols (void)
674 {
675 bfd_vma addr_mask = 1;
676 struct reloc_list *r;
677
678 /* Avoid a shift by the width of type. */
679 addr_mask <<= bfd_arch_bits_per_address (stdoutput) - 1;
680 addr_mask <<= 1;
681 addr_mask -= 1;
682
683 for (r = reloc_list; r; r = r->next)
684 {
685 reloc_howto_type *howto = r->u.a.howto;
686 expressionS *symval;
687 symbolS *sym;
688 bfd_vma offset, addend;
689 asection *sec;
690
691 resolve_symbol_value (r->u.a.offset_sym);
692 symval = symbol_get_value_expression (r->u.a.offset_sym);
693
694 offset = 0;
695 sym = NULL;
696 if (symval->X_op == O_constant)
697 sym = r->u.a.offset_sym;
698 else if (symval->X_op == O_symbol)
699 {
700 sym = symval->X_add_symbol;
701 offset = symval->X_add_number;
702 symval = symbol_get_value_expression (symval->X_add_symbol);
703 }
704 if (sym == NULL
705 || symval->X_op != O_constant
706 || (sec = S_GET_SEGMENT (sym)) == NULL
707 || !SEG_NORMAL (sec))
708 {
709 as_bad_where (r->file, r->line, _("invalid offset expression"));
710 sec = NULL;
711 }
712 else
713 offset += S_GET_VALUE (sym);
714
715 sym = NULL;
716 addend = r->u.a.addend;
717 if (r->u.a.sym != NULL)
718 {
719 resolve_symbol_value (r->u.a.sym);
720 symval = symbol_get_value_expression (r->u.a.sym);
721 if (symval->X_op == O_constant)
722 sym = r->u.a.sym;
723 else if (symval->X_op == O_symbol)
724 {
725 sym = symval->X_add_symbol;
726 addend += symval->X_add_number;
727 symval = symbol_get_value_expression (symval->X_add_symbol);
728 }
729 if (symval->X_op != O_constant)
730 {
731 as_bad_where (r->file, r->line, _("invalid reloc expression"));
732 sec = NULL;
733 }
734 else if (sym != NULL && sec != NULL)
735 {
736 /* Convert relocs against local symbols to refer to the
737 corresponding section symbol plus offset instead. Keep
738 PC-relative relocs of the REL variety intact though to
739 prevent the offset from overflowing the relocated field,
740 unless it has enough bits to cover the whole address
741 space. */
742 if (S_IS_LOCAL (sym) && !symbol_section_p (sym)
743 && (sec->use_rela_p
744 || (howto->partial_inplace
745 && (!howto->pc_relative
746 || howto->src_mask == addr_mask))))
747 {
748 asection *symsec = S_GET_SEGMENT (sym);
749 if (!(((symsec->flags & SEC_MERGE) != 0
750 && addend != 0)
751 || (symsec->flags & SEC_THREAD_LOCAL) != 0))
752 {
753 addend += S_GET_VALUE (sym);
754 sym = section_symbol (symsec);
755 }
756 }
757 symbol_mark_used_in_reloc (sym);
758 }
759 }
760 if (sym == NULL)
761 {
762 if (abs_section_sym == NULL)
763 abs_section_sym = section_symbol (absolute_section);
764 sym = abs_section_sym;
765 }
766
767 r->u.b.sec = sec;
768 r->u.b.s = symbol_get_bfdsym (sym);
769 r->u.b.r.sym_ptr_ptr = &r->u.b.s;
770 r->u.b.r.address = offset;
771 r->u.b.r.addend = addend;
772 r->u.b.r.howto = howto;
773 }
774 }
775
776 /* This pass over fixups decides whether symbols can be replaced with
777 section symbols. */
778
779 static void
780 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
781 asection *sec,
782 void *xxx ATTRIBUTE_UNUSED)
783 {
784 segment_info_type *seginfo = seg_info (sec);
785 fixS *fixp;
786
787 if (seginfo == NULL)
788 return;
789
790 dump_section_relocs (abfd, sec, stderr);
791
792 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
793 if (fixp->fx_done)
794 /* Ignore it. */
795 ;
796 else if (fixp->fx_addsy)
797 {
798 symbolS *sym;
799 asection *symsec;
800
801 #ifdef DEBUG5
802 fprintf (stderr, "\n\nadjusting fixup:\n");
803 print_fixup (fixp);
804 #endif
805
806 sym = fixp->fx_addsy;
807
808 /* All symbols should have already been resolved at this
809 point. It is possible to see unresolved expression
810 symbols, though, since they are not in the regular symbol
811 table. */
812 resolve_symbol_value (sym);
813
814 if (fixp->fx_subsy != NULL)
815 resolve_symbol_value (fixp->fx_subsy);
816
817 /* If this symbol is equated to an undefined or common symbol,
818 convert the fixup to being against that symbol. */
819 while (symbol_equated_reloc_p (sym)
820 || S_IS_WEAKREFR (sym))
821 {
822 symbolS *newsym = symbol_get_value_expression (sym)->X_add_symbol;
823 if (sym == newsym)
824 break;
825 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
826 fixp->fx_addsy = newsym;
827 sym = newsym;
828 }
829
830 if (symbol_mri_common_p (sym))
831 {
832 fixp->fx_offset += S_GET_VALUE (sym);
833 fixp->fx_addsy = symbol_get_value_expression (sym)->X_add_symbol;
834 continue;
835 }
836
837 /* If the symbol is undefined, common, weak, or global (ELF
838 shared libs), we can't replace it with the section symbol. */
839 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
840 continue;
841
842 /* Is there some other (target cpu dependent) reason we can't adjust
843 this one? (E.g. relocations involving function addresses on
844 the PA. */
845 #ifdef tc_fix_adjustable
846 if (! tc_fix_adjustable (fixp))
847 continue;
848 #endif
849
850 /* Since we're reducing to section symbols, don't attempt to reduce
851 anything that's already using one. */
852 if (symbol_section_p (sym))
853 continue;
854
855 symsec = S_GET_SEGMENT (sym);
856 if (symsec == NULL)
857 abort ();
858
859 if (bfd_is_abs_section (symsec)
860 || symsec == reg_section)
861 {
862 /* The fixup_segment routine normally will not use this
863 symbol in a relocation. */
864 continue;
865 }
866
867 /* Don't try to reduce relocs which refer to non-local symbols
868 in .linkonce sections. It can lead to confusion when a
869 debugging section refers to a .linkonce section. I hope
870 this will always be correct. */
871 if (symsec != sec && ! S_IS_LOCAL (sym))
872 {
873 if ((symsec->flags & SEC_LINK_ONCE) != 0
874 || (IS_ELF
875 /* The GNU toolchain uses an extension for ELF: a
876 section beginning with the magic string
877 .gnu.linkonce is a linkonce section. */
878 && strncmp (segment_name (symsec), ".gnu.linkonce",
879 sizeof ".gnu.linkonce" - 1) == 0))
880 continue;
881 }
882
883 /* Never adjust a reloc against local symbol in a merge section
884 with non-zero addend. */
885 if ((symsec->flags & SEC_MERGE) != 0
886 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
887 continue;
888
889 /* Never adjust a reloc against TLS local symbol. */
890 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
891 continue;
892
893 /* We refetch the segment when calling section_symbol, rather
894 than using symsec, because S_GET_VALUE may wind up changing
895 the section when it calls resolve_symbol_value. */
896 fixp->fx_offset += S_GET_VALUE (sym);
897 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
898 #ifdef DEBUG5
899 fprintf (stderr, "\nadjusted fixup:\n");
900 print_fixup (fixp);
901 #endif
902 }
903
904 dump_section_relocs (abfd, sec, stderr);
905 }
906
907 /* fixup_segment()
908
909 Go through all the fixS's in a segment and see which ones can be
910 handled now. (These consist of fixS where we have since discovered
911 the value of a symbol, or the address of the frag involved.)
912 For each one, call md_apply_fix to put the fix into the frag data.
913 Ones that we couldn't completely handle here will be output later
914 by emit_relocations. */
915
916 static void
917 fixup_segment (fixS *fixP, segT this_segment)
918 {
919 valueT add_number;
920 fragS *fragP;
921 segT add_symbol_segment = absolute_section;
922
923 if (fixP != NULL && abs_section_sym == NULL)
924 abs_section_sym = section_symbol (absolute_section);
925
926 /* If the linker is doing the relaxing, we must not do any fixups.
927
928 Well, strictly speaking that's not true -- we could do any that
929 are PC-relative and don't cross regions that could change size. */
930 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
931 {
932 for (; fixP; fixP = fixP->fx_next)
933 if (!fixP->fx_done)
934 {
935 if (fixP->fx_addsy == NULL)
936 {
937 /* There was no symbol required by this relocation.
938 However, BFD doesn't really handle relocations
939 without symbols well. So fake up a local symbol in
940 the absolute section. */
941 fixP->fx_addsy = abs_section_sym;
942 }
943 symbol_mark_used_in_reloc (fixP->fx_addsy);
944 if (fixP->fx_subsy != NULL)
945 symbol_mark_used_in_reloc (fixP->fx_subsy);
946 }
947 return;
948 }
949
950 for (; fixP; fixP = fixP->fx_next)
951 {
952 #ifdef DEBUG5
953 fprintf (stderr, "\nprocessing fixup:\n");
954 print_fixup (fixP);
955 #endif
956
957 fragP = fixP->fx_frag;
958 know (fragP);
959 #ifdef TC_VALIDATE_FIX
960 TC_VALIDATE_FIX (fixP, this_segment, skip);
961 #endif
962 add_number = fixP->fx_offset;
963
964 if (fixP->fx_addsy != NULL)
965 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
966
967 if (fixP->fx_subsy != NULL)
968 {
969 segT sub_symbol_segment;
970 resolve_symbol_value (fixP->fx_subsy);
971 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
972 if (fixP->fx_addsy != NULL
973 && sub_symbol_segment == add_symbol_segment
974 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
975 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
976 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
977 {
978 add_number += S_GET_VALUE (fixP->fx_addsy);
979 add_number -= S_GET_VALUE (fixP->fx_subsy);
980 fixP->fx_offset = add_number;
981 fixP->fx_addsy = NULL;
982 fixP->fx_subsy = NULL;
983 #ifdef TC_M68K
984 /* See the comment below about 68k weirdness. */
985 fixP->fx_pcrel = 0;
986 #endif
987 }
988 else if (sub_symbol_segment == absolute_section
989 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
990 && !TC_FORCE_RELOCATION_SUB_ABS (fixP, add_symbol_segment))
991 {
992 add_number -= S_GET_VALUE (fixP->fx_subsy);
993 fixP->fx_offset = add_number;
994 fixP->fx_subsy = NULL;
995 }
996 else if (sub_symbol_segment == this_segment
997 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
998 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP, add_symbol_segment))
999 {
1000 add_number -= S_GET_VALUE (fixP->fx_subsy);
1001 fixP->fx_offset = (add_number + fixP->fx_dot_value
1002 + fixP->fx_dot_frag->fr_address);
1003
1004 /* Make it pc-relative. If the back-end code has not
1005 selected a pc-relative reloc, cancel the adjustment
1006 we do later on all pc-relative relocs. */
1007 if (0
1008 #ifdef TC_M68K
1009 /* Do this for m68k even if it's already described
1010 as pc-relative. On the m68k, an operand of
1011 "pc@(foo-.-2)" should address "foo" in a
1012 pc-relative mode. */
1013 || 1
1014 #endif
1015 || !fixP->fx_pcrel)
1016 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
1017 fixP->fx_subsy = NULL;
1018 fixP->fx_pcrel = 1;
1019 }
1020 else if (!TC_VALIDATE_FIX_SUB (fixP, add_symbol_segment))
1021 {
1022 if (!md_register_arithmetic
1023 && (add_symbol_segment == reg_section
1024 || sub_symbol_segment == reg_section))
1025 as_bad_where (fixP->fx_file, fixP->fx_line,
1026 _("register value used as expression"));
1027 else
1028 as_bad_where (fixP->fx_file, fixP->fx_line,
1029 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
1030 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
1031 segment_name (add_symbol_segment),
1032 S_GET_NAME (fixP->fx_subsy),
1033 segment_name (sub_symbol_segment));
1034 }
1035 else if (sub_symbol_segment != undefined_section
1036 && ! bfd_is_com_section (sub_symbol_segment)
1037 && MD_APPLY_SYM_VALUE (fixP))
1038 add_number -= S_GET_VALUE (fixP->fx_subsy);
1039 }
1040
1041 if (fixP->fx_addsy)
1042 {
1043 if (add_symbol_segment == this_segment
1044 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1045 && !TC_FORCE_RELOCATION_LOCAL (fixP))
1046 {
1047 /* This fixup was made when the symbol's segment was
1048 SEG_UNKNOWN, but it is now in the local segment.
1049 So we know how to do the address without relocation. */
1050 add_number += S_GET_VALUE (fixP->fx_addsy);
1051 fixP->fx_offset = add_number;
1052 if (fixP->fx_pcrel)
1053 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1054 fixP->fx_addsy = NULL;
1055 fixP->fx_pcrel = 0;
1056 }
1057 else if (add_symbol_segment == absolute_section
1058 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1059 && !TC_FORCE_RELOCATION_ABS (fixP))
1060 {
1061 add_number += S_GET_VALUE (fixP->fx_addsy);
1062 fixP->fx_offset = add_number;
1063 fixP->fx_addsy = NULL;
1064 }
1065 else if (add_symbol_segment != undefined_section
1066 && ! bfd_is_com_section (add_symbol_segment)
1067 && MD_APPLY_SYM_VALUE (fixP))
1068 add_number += S_GET_VALUE (fixP->fx_addsy);
1069 }
1070
1071 if (fixP->fx_pcrel)
1072 {
1073 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1074 if (!fixP->fx_done && fixP->fx_addsy == NULL)
1075 {
1076 /* There was no symbol required by this relocation.
1077 However, BFD doesn't really handle relocations
1078 without symbols well. So fake up a local symbol in
1079 the absolute section. */
1080 fixP->fx_addsy = abs_section_sym;
1081 }
1082 }
1083
1084 if (!fixP->fx_done)
1085 md_apply_fix (fixP, &add_number, this_segment);
1086
1087 if (!fixP->fx_done)
1088 {
1089 if (fixP->fx_addsy == NULL)
1090 fixP->fx_addsy = abs_section_sym;
1091 symbol_mark_used_in_reloc (fixP->fx_addsy);
1092 if (fixP->fx_subsy != NULL)
1093 symbol_mark_used_in_reloc (fixP->fx_subsy);
1094 }
1095
1096 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
1097 {
1098 if (fixP->fx_size < sizeof (valueT))
1099 {
1100 valueT mask;
1101
1102 mask = 0;
1103 mask--; /* Set all bits to one. */
1104 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
1105 if ((add_number & mask) != 0 && (add_number & mask) != mask)
1106 {
1107 char buf[50], buf2[50];
1108 sprint_value (buf, fragP->fr_address + fixP->fx_where);
1109 if (add_number > 1000)
1110 sprint_value (buf2, add_number);
1111 else
1112 sprintf (buf2, "%ld", (long) add_number);
1113 as_bad_where (fixP->fx_file, fixP->fx_line,
1114 ngettext ("value of %s too large for field "
1115 "of %d byte at %s",
1116 "value of %s too large for field "
1117 "of %d bytes at %s",
1118 fixP->fx_size),
1119 buf2, fixP->fx_size, buf);
1120 } /* Generic error checking. */
1121 }
1122 #ifdef WARN_SIGNED_OVERFLOW_WORD
1123 /* Warn if a .word value is too large when treated as a signed
1124 number. We already know it is not too negative. This is to
1125 catch over-large switches generated by gcc on the 68k. */
1126 if (!flag_signed_overflow_ok
1127 && fixP->fx_size == 2
1128 && add_number > 0x7fff)
1129 as_bad_where (fixP->fx_file, fixP->fx_line,
1130 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
1131 (long) add_number,
1132 (long) (fragP->fr_address + fixP->fx_where));
1133 #endif
1134 } /* Not a bit fix. */
1135
1136 #ifdef TC_VALIDATE_FIX
1137 skip: ATTRIBUTE_UNUSED_LABEL
1138 ;
1139 #endif
1140 #ifdef DEBUG5
1141 fprintf (stderr, "result:\n");
1142 print_fixup (fixP);
1143 #endif
1144 } /* For each fixS in this segment. */
1145 }
1146
1147 static void
1148 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
1149 asection *sec,
1150 void *xxx ATTRIBUTE_UNUSED)
1151 {
1152 segment_info_type *seginfo = seg_info (sec);
1153
1154 fixup_segment (seginfo->fix_root, sec);
1155 }
1156
1157 static void
1158 install_reloc (asection *sec, arelent *reloc, fragS *fragp,
1159 const char *file, unsigned int line)
1160 {
1161 char *err;
1162 bfd_reloc_status_type s;
1163 asymbol *sym;
1164
1165 if (reloc->sym_ptr_ptr != NULL
1166 && (sym = *reloc->sym_ptr_ptr) != NULL
1167 && (sym->flags & BSF_KEEP) == 0
1168 && ((sym->flags & BSF_SECTION_SYM) == 0
1169 || (EMIT_SECTION_SYMBOLS
1170 && !bfd_is_abs_section (sym->section))))
1171 as_bad_where (file, line, _("redefined symbol cannot be used on reloc"));
1172
1173 s = bfd_install_relocation (stdoutput, reloc,
1174 fragp->fr_literal, fragp->fr_address,
1175 sec, &err);
1176 switch (s)
1177 {
1178 case bfd_reloc_ok:
1179 break;
1180 case bfd_reloc_overflow:
1181 as_bad_where (file, line, _("relocation overflow"));
1182 break;
1183 case bfd_reloc_outofrange:
1184 as_bad_where (file, line, _("relocation out of range"));
1185 break;
1186 default:
1187 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1188 file, line, s);
1189 }
1190 }
1191
1192 static fragS *
1193 get_frag_for_reloc (fragS *last_frag,
1194 const segment_info_type *seginfo,
1195 const struct reloc_list *r)
1196 {
1197 fragS *f;
1198
1199 for (f = last_frag; f != NULL; f = f->fr_next)
1200 if (f->fr_address <= r->u.b.r.address
1201 && r->u.b.r.address < f->fr_address + f->fr_fix)
1202 return f;
1203
1204 for (f = seginfo->frchainP->frch_root; f != NULL; f = f->fr_next)
1205 if (f->fr_address <= r->u.b.r.address
1206 && r->u.b.r.address < f->fr_address + f->fr_fix)
1207 return f;
1208
1209 for (f = seginfo->frchainP->frch_root; f != NULL; f = f->fr_next)
1210 if (f->fr_address <= r->u.b.r.address
1211 && r->u.b.r.address <= f->fr_address + f->fr_fix)
1212 return f;
1213
1214 as_bad_where (r->file, r->line,
1215 _("reloc not within (fixed part of) section"));
1216 return NULL;
1217 }
1218
1219 static void
1220 write_relocs (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1221 {
1222 segment_info_type *seginfo = seg_info (sec);
1223 unsigned int n;
1224 struct reloc_list *my_reloc_list, **rp, *r;
1225 arelent **relocs;
1226 fixS *fixp;
1227 fragS *last_frag;
1228
1229 /* If seginfo is NULL, we did not create this section; don't do
1230 anything with it. */
1231 if (seginfo == NULL)
1232 return;
1233
1234 n = 0;
1235 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
1236 if (!fixp->fx_done)
1237 n++;
1238
1239 #ifdef RELOC_EXPANSION_POSSIBLE
1240 n *= MAX_RELOC_EXPANSION;
1241 #endif
1242
1243 /* Extract relocs for this section from reloc_list. */
1244 rp = &reloc_list;
1245 my_reloc_list = NULL;
1246 while ((r = *rp) != NULL)
1247 {
1248 if (r->u.b.sec == sec)
1249 {
1250 *rp = r->next;
1251 r->next = my_reloc_list;
1252 my_reloc_list = r;
1253 n++;
1254 }
1255 else
1256 rp = &r->next;
1257 }
1258
1259 relocs = XCNEWVEC (arelent *, n);
1260
1261 n = 0;
1262 r = my_reloc_list;
1263 last_frag = NULL;
1264 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
1265 {
1266 int fx_size, slack;
1267 offsetT loc;
1268 arelent **reloc;
1269 #ifndef RELOC_EXPANSION_POSSIBLE
1270 arelent *rel;
1271
1272 reloc = &rel;
1273 #endif
1274
1275 if (fixp->fx_done)
1276 continue;
1277
1278 fx_size = fixp->fx_size;
1279 slack = TC_FX_SIZE_SLACK (fixp);
1280 if (slack > 0)
1281 fx_size = fx_size > slack ? fx_size - slack : 0;
1282 loc = fixp->fx_where + fx_size;
1283 if (slack >= 0 && loc > fixp->fx_frag->fr_fix)
1284 as_bad_where (fixp->fx_file, fixp->fx_line,
1285 _("internal error: fixup not contained within frag"));
1286
1287 #ifndef RELOC_EXPANSION_POSSIBLE
1288 *reloc = tc_gen_reloc (sec, fixp);
1289 #else
1290 reloc = tc_gen_reloc (sec, fixp);
1291 #endif
1292
1293 while (*reloc)
1294 {
1295 while (r != NULL && r->u.b.r.address < (*reloc)->address)
1296 {
1297 fragS *f = get_frag_for_reloc (last_frag, seginfo, r);
1298 if (f != NULL)
1299 {
1300 last_frag = f;
1301 relocs[n++] = &r->u.b.r;
1302 install_reloc (sec, &r->u.b.r, f, r->file, r->line);
1303 }
1304 r = r->next;
1305 }
1306 relocs[n++] = *reloc;
1307 install_reloc (sec, *reloc, fixp->fx_frag,
1308 fixp->fx_file, fixp->fx_line);
1309 #ifndef RELOC_EXPANSION_POSSIBLE
1310 break;
1311 #else
1312 reloc++;
1313 #endif
1314 }
1315 }
1316
1317 while (r != NULL)
1318 {
1319 fragS *f = get_frag_for_reloc (last_frag, seginfo, r);
1320 if (f != NULL)
1321 {
1322 last_frag = f;
1323 relocs[n++] = &r->u.b.r;
1324 install_reloc (sec, &r->u.b.r, f, r->file, r->line);
1325 }
1326 r = r->next;
1327 }
1328
1329 #ifdef DEBUG4
1330 {
1331 unsigned int k, j, nsyms;
1332 asymbol **sympp;
1333 sympp = bfd_get_outsymbols (stdoutput);
1334 nsyms = bfd_get_symcount (stdoutput);
1335 for (k = 0; k < n; k++)
1336 if (((*relocs[k]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1337 {
1338 for (j = 0; j < nsyms; j++)
1339 if (sympp[j] == *relocs[k]->sym_ptr_ptr)
1340 break;
1341 if (j == nsyms)
1342 abort ();
1343 }
1344 }
1345 #endif
1346
1347 if (n)
1348 {
1349 flagword flags = bfd_get_section_flags (abfd, sec);
1350 flags |= SEC_RELOC;
1351 bfd_set_section_flags (abfd, sec, flags);
1352 bfd_set_reloc (stdoutput, sec, relocs, n);
1353 }
1354
1355 #ifdef SET_SECTION_RELOCS
1356 SET_SECTION_RELOCS (sec, relocs, n);
1357 #endif
1358
1359 #ifdef DEBUG3
1360 {
1361 unsigned int k;
1362
1363 fprintf (stderr, "relocs for sec %s\n", sec->name);
1364 for (k = 0; k < n; k++)
1365 {
1366 arelent *rel = relocs[k];
1367 asymbol *s = *rel->sym_ptr_ptr;
1368 fprintf (stderr, " reloc %2d @%p off %4lx : sym %-10s addend %lx\n",
1369 k, rel, (unsigned long)rel->address, s->name,
1370 (unsigned long)rel->addend);
1371 }
1372 }
1373 #endif
1374 }
1375
1376 static int
1377 compress_frag (struct z_stream_s *strm, const char *contents, int in_size,
1378 fragS **last_newf, struct obstack *ob)
1379 {
1380 int out_size;
1381 int total_out_size = 0;
1382 fragS *f = *last_newf;
1383 char *next_out;
1384 int avail_out;
1385
1386 /* Call the compression routine repeatedly until it has finished
1387 processing the frag. */
1388 while (in_size > 0)
1389 {
1390 /* Reserve all the space available in the current chunk.
1391 If none is available, start a new frag. */
1392 avail_out = obstack_room (ob);
1393 if (avail_out <= 0)
1394 {
1395 obstack_finish (ob);
1396 f = frag_alloc (ob);
1397 f->fr_type = rs_fill;
1398 (*last_newf)->fr_next = f;
1399 *last_newf = f;
1400 avail_out = obstack_room (ob);
1401 }
1402 if (avail_out <= 0)
1403 as_fatal (_("can't extend frag"));
1404 next_out = obstack_next_free (ob);
1405 obstack_blank_fast (ob, avail_out);
1406 out_size = compress_data (strm, &contents, &in_size,
1407 &next_out, &avail_out);
1408 if (out_size < 0)
1409 return -1;
1410
1411 f->fr_fix += out_size;
1412 total_out_size += out_size;
1413
1414 /* Return unused space. */
1415 if (avail_out > 0)
1416 obstack_blank_fast (ob, -avail_out);
1417 }
1418
1419 return total_out_size;
1420 }
1421
1422 static void
1423 compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1424 {
1425 segment_info_type *seginfo = seg_info (sec);
1426 fragS *f;
1427 fragS *first_newf;
1428 fragS *last_newf;
1429 struct obstack *ob = &seginfo->frchainP->frch_obstack;
1430 bfd_size_type uncompressed_size = (bfd_size_type) sec->size;
1431 bfd_size_type compressed_size;
1432 const char *section_name;
1433 char *compressed_name;
1434 char *header;
1435 struct z_stream_s *strm;
1436 int x;
1437 flagword flags = bfd_get_section_flags (abfd, sec);
1438 unsigned int header_size, compression_header_size;
1439
1440 if (seginfo == NULL
1441 || sec->size < 32
1442 || (flags & (SEC_ALLOC | SEC_HAS_CONTENTS)) == SEC_ALLOC)
1443 return;
1444
1445 section_name = bfd_get_section_name (stdoutput, sec);
1446 if (strncmp (section_name, ".debug_", 7) != 0)
1447 return;
1448
1449 strm = compress_init ();
1450 if (strm == NULL)
1451 return;
1452
1453 if (flag_compress_debug == COMPRESS_DEBUG_GABI_ZLIB)
1454 {
1455 compression_header_size
1456 = bfd_get_compression_header_size (stdoutput, NULL);
1457 header_size = compression_header_size;
1458 }
1459 else
1460 {
1461 compression_header_size = 0;
1462 header_size = 12;
1463 }
1464
1465 /* Create a new frag to contain the compression header. */
1466 first_newf = frag_alloc (ob);
1467 if (obstack_room (ob) < header_size)
1468 first_newf = frag_alloc (ob);
1469 if (obstack_room (ob) < header_size)
1470 as_fatal (ngettext ("can't extend frag %lu char",
1471 "can't extend frag %lu chars",
1472 (unsigned long) header_size),
1473 (unsigned long) header_size);
1474 last_newf = first_newf;
1475 obstack_blank_fast (ob, header_size);
1476 last_newf->fr_type = rs_fill;
1477 last_newf->fr_fix = header_size;
1478 header = last_newf->fr_literal;
1479 compressed_size = header_size;
1480
1481 /* Stream the frags through the compression engine, adding new frags
1482 as necessary to accommodate the compressed output. */
1483 for (f = seginfo->frchainP->frch_root;
1484 f;
1485 f = f->fr_next)
1486 {
1487 offsetT fill_size;
1488 char *fill_literal;
1489 offsetT count;
1490 int out_size;
1491
1492 gas_assert (f->fr_type == rs_fill);
1493 if (f->fr_fix)
1494 {
1495 out_size = compress_frag (strm, f->fr_literal, f->fr_fix,
1496 &last_newf, ob);
1497 if (out_size < 0)
1498 return;
1499 compressed_size += out_size;
1500 }
1501 fill_literal = f->fr_literal + f->fr_fix;
1502 fill_size = f->fr_var;
1503 count = f->fr_offset;
1504 gas_assert (count >= 0);
1505 if (fill_size && count)
1506 {
1507 while (count--)
1508 {
1509 out_size = compress_frag (strm, fill_literal, (int) fill_size,
1510 &last_newf, ob);
1511 if (out_size < 0)
1512 return;
1513 compressed_size += out_size;
1514 }
1515 }
1516 }
1517
1518 /* Flush the compression state. */
1519 for (;;)
1520 {
1521 int avail_out;
1522 char *next_out;
1523 int out_size;
1524
1525 /* Reserve all the space available in the current chunk.
1526 If none is available, start a new frag. */
1527 avail_out = obstack_room (ob);
1528 if (avail_out <= 0)
1529 {
1530 fragS *newf;
1531
1532 obstack_finish (ob);
1533 newf = frag_alloc (ob);
1534 newf->fr_type = rs_fill;
1535 last_newf->fr_next = newf;
1536 last_newf = newf;
1537 avail_out = obstack_room (ob);
1538 }
1539 if (avail_out <= 0)
1540 as_fatal (_("can't extend frag"));
1541 next_out = obstack_next_free (ob);
1542 obstack_blank_fast (ob, avail_out);
1543 x = compress_finish (strm, &next_out, &avail_out, &out_size);
1544 if (x < 0)
1545 return;
1546
1547 last_newf->fr_fix += out_size;
1548 compressed_size += out_size;
1549
1550 /* Return unused space. */
1551 if (avail_out > 0)
1552 obstack_blank_fast (ob, -avail_out);
1553
1554 if (x == 0)
1555 break;
1556 }
1557
1558 /* PR binutils/18087: If compression didn't make the section smaller,
1559 just keep it uncompressed. */
1560 if (compressed_size >= uncompressed_size)
1561 return;
1562
1563 /* Replace the uncompressed frag list with the compressed frag list. */
1564 seginfo->frchainP->frch_root = first_newf;
1565 seginfo->frchainP->frch_last = last_newf;
1566
1567 /* Update the section size and its name. */
1568 bfd_update_compression_header (abfd, (bfd_byte *) header, sec);
1569 x = bfd_set_section_size (abfd, sec, compressed_size);
1570 gas_assert (x);
1571 if (!compression_header_size)
1572 {
1573 compressed_name = concat (".z", section_name + 1, (char *) NULL);
1574 bfd_section_name (stdoutput, sec) = compressed_name;
1575 }
1576 }
1577
1578 #ifndef md_generate_nops
1579 /* Genenerate COUNT bytes of no-op instructions to WHERE. A target
1580 backend must override this with proper no-op instructions. */
1581
1582 static void
1583 md_generate_nops (fragS *f ATTRIBUTE_UNUSED,
1584 char *where ATTRIBUTE_UNUSED,
1585 offsetT count ATTRIBUTE_UNUSED,
1586 int control ATTRIBUTE_UNUSED)
1587 {
1588 as_bad (_("unimplemented .nops directive"));
1589 }
1590 #endif
1591
1592 static void
1593 write_contents (bfd *abfd ATTRIBUTE_UNUSED,
1594 asection *sec,
1595 void *xxx ATTRIBUTE_UNUSED)
1596 {
1597 segment_info_type *seginfo = seg_info (sec);
1598 addressT offset = 0;
1599 fragS *f;
1600
1601 /* Write out the frags. */
1602 if (seginfo == NULL
1603 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1604 return;
1605
1606 for (f = seginfo->frchainP->frch_root;
1607 f;
1608 f = f->fr_next)
1609 {
1610 int x;
1611 addressT fill_size;
1612 char *fill_literal;
1613 offsetT count;
1614
1615 gas_assert (f->fr_type == rs_fill || f->fr_type == rs_fill_nop);
1616 if (f->fr_fix)
1617 {
1618 x = bfd_set_section_contents (stdoutput, sec,
1619 f->fr_literal, (file_ptr) offset,
1620 (bfd_size_type) f->fr_fix);
1621 if (!x)
1622 as_fatal (ngettext ("can't write %ld byte "
1623 "to section %s of %s: '%s'",
1624 "can't write %ld bytes "
1625 "to section %s of %s: '%s'",
1626 (long) f->fr_fix),
1627 (long) f->fr_fix,
1628 sec->name, stdoutput->filename,
1629 bfd_errmsg (bfd_get_error ()));
1630 offset += f->fr_fix;
1631 }
1632
1633 fill_size = f->fr_var;
1634 count = f->fr_offset;
1635 fill_literal = f->fr_literal + f->fr_fix;
1636
1637 if (f->fr_type == rs_fill_nop)
1638 {
1639 gas_assert (count >= 0 && fill_size == 1);
1640 if (count > 0)
1641 {
1642 char *buf = xmalloc (count);
1643 md_generate_nops (f, buf, count, *fill_literal);
1644 x = bfd_set_section_contents
1645 (stdoutput, sec, buf, (file_ptr) offset,
1646 (bfd_size_type) count);
1647 if (!x)
1648 as_fatal (ngettext ("can't fill %ld byte "
1649 "in section %s of %s: '%s'",
1650 "can't fill %ld bytes "
1651 "in section %s of %s: '%s'",
1652 (long) count), (long) count,
1653 sec->name, stdoutput->filename,
1654 bfd_errmsg (bfd_get_error ()));
1655 offset += count;
1656 free (buf);
1657 }
1658 continue;
1659 }
1660
1661 gas_assert (count >= 0);
1662 if (fill_size && count)
1663 {
1664 char buf[256];
1665 if (fill_size > sizeof (buf))
1666 {
1667 /* Do it the old way. Can this ever happen? */
1668 while (count--)
1669 {
1670 x = bfd_set_section_contents (stdoutput, sec,
1671 fill_literal,
1672 (file_ptr) offset,
1673 (bfd_size_type) fill_size);
1674 if (!x)
1675 as_fatal (ngettext ("can't fill %ld byte "
1676 "in section %s of %s: '%s'",
1677 "can't fill %ld bytes "
1678 "in section %s of %s: '%s'",
1679 (long) fill_size),
1680 (long) fill_size,
1681 sec->name, stdoutput->filename,
1682 bfd_errmsg (bfd_get_error ()));
1683 offset += fill_size;
1684 }
1685 }
1686 else
1687 {
1688 /* Build a buffer full of fill objects and output it as
1689 often as necessary. This saves on the overhead of
1690 potentially lots of bfd_set_section_contents calls. */
1691 int n_per_buf, i;
1692 if (fill_size == 1)
1693 {
1694 n_per_buf = sizeof (buf);
1695 memset (buf, *fill_literal, n_per_buf);
1696 }
1697 else
1698 {
1699 char *bufp;
1700 n_per_buf = sizeof (buf) / fill_size;
1701 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1702 memcpy (bufp, fill_literal, fill_size);
1703 }
1704 for (; count > 0; count -= n_per_buf)
1705 {
1706 n_per_buf = n_per_buf > count ? count : n_per_buf;
1707 x = bfd_set_section_contents
1708 (stdoutput, sec, buf, (file_ptr) offset,
1709 (bfd_size_type) n_per_buf * fill_size);
1710 if (!x)
1711 as_fatal (ngettext ("can't fill %ld byte "
1712 "in section %s of %s: '%s'",
1713 "can't fill %ld bytes "
1714 "in section %s of %s: '%s'",
1715 (long) (n_per_buf * fill_size)),
1716 (long) (n_per_buf * fill_size),
1717 sec->name, stdoutput->filename,
1718 bfd_errmsg (bfd_get_error ()));
1719 offset += n_per_buf * fill_size;
1720 }
1721 }
1722 }
1723 }
1724 }
1725
1726 static void
1727 merge_data_into_text (void)
1728 {
1729 seg_info (text_section)->frchainP->frch_last->fr_next =
1730 seg_info (data_section)->frchainP->frch_root;
1731 seg_info (text_section)->frchainP->frch_last =
1732 seg_info (data_section)->frchainP->frch_last;
1733 seg_info (data_section)->frchainP = 0;
1734 }
1735
1736 static void
1737 set_symtab (void)
1738 {
1739 int nsyms;
1740 asymbol **asympp;
1741 symbolS *symp;
1742 bfd_boolean result;
1743
1744 /* Count symbols. We can't rely on a count made by the loop in
1745 write_object_file, because *_frob_file may add a new symbol or
1746 two. */
1747 nsyms = 0;
1748 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1749 nsyms++;
1750
1751 if (nsyms)
1752 {
1753 int i;
1754 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1755
1756 asympp = (asymbol **) bfd_alloc (stdoutput, amt);
1757 symp = symbol_rootP;
1758 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1759 {
1760 asympp[i] = symbol_get_bfdsym (symp);
1761 if (asympp[i]->flags != BSF_SECTION_SYM
1762 || !(bfd_is_const_section (asympp[i]->section)
1763 && asympp[i]->section->symbol == asympp[i]))
1764 asympp[i]->flags |= BSF_KEEP;
1765 symbol_mark_written (symp);
1766 }
1767 }
1768 else
1769 asympp = 0;
1770 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1771 gas_assert (result);
1772 symbol_table_frozen = 1;
1773 }
1774
1775 /* Finish the subsegments. After every sub-segment, we fake an
1776 ".align ...". This conforms to BSD4.2 brain-damage. We then fake
1777 ".fill 0" because that is the kind of frag that requires least
1778 thought. ".align" frags like to have a following frag since that
1779 makes calculating their intended length trivial. */
1780
1781 #ifndef SUB_SEGMENT_ALIGN
1782 #ifdef HANDLE_ALIGN
1783 /* The last subsegment gets an alignment corresponding to the alignment
1784 of the section. This allows proper nop-filling at the end of
1785 code-bearing sections. */
1786 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1787 (!(FRCHAIN)->frch_next && subseg_text_p (SEG) \
1788 && !do_not_pad_sections_to_alignment \
1789 ? get_recorded_alignment (SEG) \
1790 : 0)
1791 #else
1792 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1793 #endif
1794 #endif
1795
1796 static void
1797 subsegs_finish_section (asection *s)
1798 {
1799 struct frchain *frchainP;
1800 segment_info_type *seginfo = seg_info (s);
1801 if (!seginfo)
1802 return;
1803
1804 for (frchainP = seginfo->frchainP;
1805 frchainP != NULL;
1806 frchainP = frchainP->frch_next)
1807 {
1808 int alignment;
1809
1810 subseg_set (s, frchainP->frch_subseg);
1811
1812 /* This now gets called even if we had errors. In that case,
1813 any alignment is meaningless, and, moreover, will look weird
1814 if we are generating a listing. */
1815 if (had_errors ())
1816 do_not_pad_sections_to_alignment = 1;
1817
1818 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1819 if ((bfd_get_section_flags (now_seg->owner, now_seg) & SEC_MERGE)
1820 && now_seg->entsize)
1821 {
1822 unsigned int entsize = now_seg->entsize;
1823 int entalign = 0;
1824
1825 while ((entsize & 1) == 0)
1826 {
1827 ++entalign;
1828 entsize >>= 1;
1829 }
1830
1831 if (entalign > alignment)
1832 alignment = entalign;
1833 }
1834
1835 if (subseg_text_p (now_seg))
1836 frag_align_code (alignment, 0);
1837 else
1838 frag_align (alignment, 0, 0);
1839
1840 /* frag_align will have left a new frag.
1841 Use this last frag for an empty ".fill".
1842
1843 For this segment ...
1844 Create a last frag. Do not leave a "being filled in frag". */
1845 frag_wane (frag_now);
1846 frag_now->fr_fix = 0;
1847 know (frag_now->fr_next == NULL);
1848 }
1849 }
1850
1851 static void
1852 subsegs_finish (void)
1853 {
1854 asection *s;
1855
1856 for (s = stdoutput->sections; s; s = s->next)
1857 subsegs_finish_section (s);
1858 }
1859
1860 #ifdef OBJ_ELF
1861 static void
1862 create_obj_attrs_section (void)
1863 {
1864 segT s;
1865 char *p;
1866 offsetT size;
1867 const char *name;
1868
1869 size = bfd_elf_obj_attr_size (stdoutput);
1870 if (size == 0)
1871 return;
1872
1873 name = get_elf_backend_data (stdoutput)->obj_attrs_section;
1874 if (!name)
1875 name = ".gnu.attributes";
1876 s = subseg_new (name, 0);
1877 elf_section_type (s)
1878 = get_elf_backend_data (stdoutput)->obj_attrs_section_type;
1879 bfd_set_section_flags (stdoutput, s, SEC_READONLY | SEC_DATA);
1880 frag_now_fix ();
1881 p = frag_more (size);
1882 bfd_elf_set_obj_attr_contents (stdoutput, (bfd_byte *)p, size);
1883
1884 subsegs_finish_section (s);
1885 relax_segment (seg_info (s)->frchainP->frch_root, s, 0);
1886 size_seg (stdoutput, s, NULL);
1887 }
1888
1889 #include "struc-symbol.h"
1890
1891 /* Create a relocation against an entry in a GNU Build attribute section. */
1892
1893 static void
1894 create_note_reloc (segT sec,
1895 symbolS * sym,
1896 bfd_size_type offset,
1897 int reloc_type,
1898 bfd_vma addend,
1899 char * note)
1900 {
1901 struct reloc_list * reloc;
1902
1903 reloc = XNEW (struct reloc_list);
1904
1905 /* We create a .b type reloc as resolve_reloc_expr_symbols() has already been called. */
1906 reloc->u.b.sec = sec;
1907 reloc->u.b.s = sym->bsym;
1908 reloc->u.b.r.sym_ptr_ptr = & reloc->u.b.s;
1909 reloc->u.b.r.address = offset;
1910 reloc->u.b.r.addend = addend;
1911 reloc->u.b.r.howto = bfd_reloc_type_lookup (stdoutput, reloc_type);
1912
1913 if (reloc->u.b.r.howto == NULL)
1914 {
1915 as_bad (_("unable to create reloc for build note"));
1916 return;
1917 }
1918
1919 reloc->file = N_("<gnu build note>");
1920 reloc->line = 0;
1921
1922 reloc->next = reloc_list;
1923 reloc_list = reloc;
1924
1925 /* For REL relocs, store the addend in the section. */
1926 if (! sec->use_rela_p
1927 /* The SH target is a special case that uses RELA relocs
1928 but still stores the addend in the word being relocated. */
1929 || strstr (bfd_get_target (stdoutput), "-sh") != NULL)
1930 {
1931 if (target_big_endian)
1932 {
1933 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1934 note[offset + 3] = addend;
1935 else
1936 note[offset + 7] = addend;
1937 }
1938 else
1939 note[offset] = addend;
1940 }
1941 }
1942
1943 static void
1944 maybe_generate_build_notes (void)
1945 {
1946 segT sec;
1947 char * note;
1948 offsetT note_size;
1949 offsetT desc_size;
1950 offsetT desc2_offset;
1951 int desc_reloc;
1952 symbolS * sym;
1953
1954 if (! flag_generate_build_notes
1955 || bfd_get_section_by_name (stdoutput,
1956 GNU_BUILD_ATTRS_SECTION_NAME) != NULL)
1957 return;
1958
1959 /* Create a GNU Build Attribute section. */
1960 sec = subseg_new (GNU_BUILD_ATTRS_SECTION_NAME, FALSE);
1961 elf_section_type (sec) = SHT_NOTE;
1962 bfd_set_section_flags (stdoutput, sec,
1963 SEC_READONLY | SEC_HAS_CONTENTS | SEC_DATA);
1964 bfd_set_section_alignment (stdoutput, sec, 2);
1965
1966 /* Create a version note. */
1967 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1968 {
1969 note_size = 28;
1970 desc_size = 8; /* Two 4-byte offsets. */
1971 desc2_offset = 24;
1972
1973 /* FIXME: The BFD backend for the CRX target does not support the
1974 BFD_RELOC_32, even though it really should. Likewise for the
1975 CR16 target. So we have special case code here... */
1976 if (strstr (bfd_get_target (stdoutput), "-crx") != NULL)
1977 desc_reloc = BFD_RELOC_CRX_NUM32;
1978 else if (strstr (bfd_get_target (stdoutput), "-cr16") != NULL)
1979 desc_reloc = BFD_RELOC_CR16_NUM32;
1980 else
1981 desc_reloc = BFD_RELOC_32;
1982 }
1983 else
1984 {
1985 note_size = 36;
1986 desc_size = 16; /* Two 8-byte offsets. */
1987 desc2_offset = 28;
1988 /* FIXME: The BFD backend for the IA64 target does not support the
1989 BFD_RELOC_64, even though it really should. The HPPA backend
1990 has a similar issue, although it does not support BFD_RELOCs at
1991 all! So we have special case code to handle these targets. */
1992 if (strstr (bfd_get_target (stdoutput), "-ia64") != NULL)
1993 desc_reloc = target_big_endian ? BFD_RELOC_IA64_DIR32MSB : BFD_RELOC_IA64_DIR32LSB;
1994 else if (strstr (bfd_get_target (stdoutput), "-hppa") != NULL)
1995 desc_reloc = 80; /* R_PARISC_DIR64. */
1996 else
1997 desc_reloc = BFD_RELOC_64;
1998 }
1999
2000 frag_now_fix ();
2001 note = frag_more (note_size);
2002 memset (note, 0, note_size);
2003
2004 if (target_big_endian)
2005 {
2006 note[3] = 8; /* strlen (name) + 1. */
2007 note[7] = desc_size; /* Two 8-byte offsets. */
2008 note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2009 note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2010 }
2011 else
2012 {
2013 note[0] = 8; /* strlen (name) + 1. */
2014 note[4] = desc_size; /* Two 8-byte offsets. */
2015 note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2016 note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2017 }
2018
2019 /* The a1 version number indicates that this note was
2020 generated by the assembler and not the gcc annobin plugin. */
2021 memcpy (note + 12, "GA$\ 13a1", 8);
2022
2023 /* Find the first code section symbol. */
2024 for (sym = symbol_rootP; sym != NULL; sym = sym->sy_next)
2025 if (sym->bsym != NULL
2026 && sym->bsym->flags & BSF_SECTION_SYM
2027 && sym->bsym->section != NULL
2028 && sym->bsym->section->flags & SEC_CODE)
2029 {
2030 /* Found one - now create a relocation against this symbol. */
2031 create_note_reloc (sec, sym, 20, desc_reloc, 0, note);
2032 break;
2033 }
2034
2035 /* Find the last code section symbol. */
2036 if (sym)
2037 {
2038 for (sym = symbol_lastP; sym != NULL; sym = sym->sy_previous)
2039 if (sym->bsym != NULL
2040 && sym->bsym->flags & BSF_SECTION_SYM
2041 && sym->bsym->section != NULL
2042 && sym->bsym->section->flags & SEC_CODE)
2043 {
2044 /* Create a relocation against the end of this symbol. */
2045 create_note_reloc (sec, sym, desc2_offset, desc_reloc,
2046 bfd_get_section_size (sym->bsym->section),
2047 note);
2048 break;
2049 }
2050 }
2051 /* else - if we were unable to find any code section symbols then
2052 probably there is no code in the output. So leaving the start
2053 and end values as zero in the note is OK. */
2054
2055 /* FIXME: Maybe add a note recording the assembler command line and version ? */
2056
2057 /* Install the note(s) into the section. */
2058 bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, note_size);
2059 subsegs_finish_section (sec);
2060 relax_segment (seg_info (sec)->frchainP->frch_root, sec, 0);
2061 size_seg (stdoutput, sec, NULL);
2062 }
2063 #endif /* OBJ_ELF */
2064
2065 /* Write the object file. */
2066
2067 void
2068 write_object_file (void)
2069 {
2070 struct relax_seg_info rsi;
2071 #ifndef WORKING_DOT_WORD
2072 fragS *fragP; /* Track along all frags. */
2073 #endif
2074
2075 subsegs_finish ();
2076
2077 #ifdef md_pre_output_hook
2078 md_pre_output_hook;
2079 #endif
2080
2081 #ifdef md_pre_relax_hook
2082 md_pre_relax_hook;
2083 #endif
2084
2085 /* From now on, we don't care about sub-segments. Build one frag chain
2086 for each segment. Linked through fr_next. */
2087
2088 /* Remove the sections created by gas for its own purposes. */
2089 {
2090 int i;
2091
2092 bfd_section_list_remove (stdoutput, reg_section);
2093 bfd_section_list_remove (stdoutput, expr_section);
2094 stdoutput->section_count -= 2;
2095 i = 0;
2096 bfd_map_over_sections (stdoutput, renumber_sections, &i);
2097 }
2098
2099 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
2100
2101 /* We have two segments. If user gave -R flag, then we must put the
2102 data frags into the text segment. Do this before relaxing so
2103 we know to take advantage of -R and make shorter addresses. */
2104 if (flag_readonly_data_in_text)
2105 {
2106 merge_data_into_text ();
2107 }
2108
2109 rsi.pass = 0;
2110 while (1)
2111 {
2112 #ifndef WORKING_DOT_WORD
2113 /* We need to reset the markers in the broken word list and
2114 associated frags between calls to relax_segment (via
2115 relax_seg). Since the broken word list is global, we do it
2116 once per round, rather than locally in relax_segment for each
2117 segment. */
2118 struct broken_word *brokp;
2119
2120 for (brokp = broken_words;
2121 brokp != (struct broken_word *) NULL;
2122 brokp = brokp->next_broken_word)
2123 {
2124 brokp->added = 0;
2125
2126 if (brokp->dispfrag != (fragS *) NULL
2127 && brokp->dispfrag->fr_type == rs_broken_word)
2128 brokp->dispfrag->fr_subtype = 0;
2129 }
2130 #endif
2131
2132 rsi.changed = 0;
2133 bfd_map_over_sections (stdoutput, relax_seg, &rsi);
2134 rsi.pass++;
2135 if (!rsi.changed)
2136 break;
2137 }
2138
2139 /* Note - Most ports will use the default value of
2140 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
2141 local symbols to be resolved, removing their frag information.
2142 Some ports however, will not have finished relaxing all of
2143 their frags and will still need the local symbol frag
2144 information. These ports can set
2145 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
2146 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
2147
2148 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
2149
2150 /* Relaxation has completed. Freeze all syms. */
2151 finalize_syms = 1;
2152
2153 dwarf2dbg_final_check ();
2154
2155 #ifdef md_post_relax_hook
2156 md_post_relax_hook;
2157 #endif
2158
2159 #ifdef OBJ_ELF
2160 if (IS_ELF)
2161 create_obj_attrs_section ();
2162 #endif
2163
2164 #ifndef WORKING_DOT_WORD
2165 {
2166 struct broken_word *lie;
2167 struct broken_word **prevP;
2168
2169 prevP = &broken_words;
2170 for (lie = broken_words; lie; lie = lie->next_broken_word)
2171 if (!lie->added)
2172 {
2173 expressionS exp;
2174
2175 subseg_change (lie->seg, lie->subseg);
2176 exp.X_op = O_subtract;
2177 exp.X_add_symbol = lie->add;
2178 exp.X_op_symbol = lie->sub;
2179 exp.X_add_number = lie->addnum;
2180 #ifdef TC_CONS_FIX_NEW
2181 TC_CONS_FIX_NEW (lie->frag,
2182 lie->word_goes_here - lie->frag->fr_literal,
2183 2, &exp, TC_PARSE_CONS_RETURN_NONE);
2184 #else
2185 fix_new_exp (lie->frag,
2186 lie->word_goes_here - lie->frag->fr_literal,
2187 2, &exp, 0, BFD_RELOC_16);
2188 #endif
2189 *prevP = lie->next_broken_word;
2190 }
2191 else
2192 prevP = &(lie->next_broken_word);
2193
2194 for (lie = broken_words; lie;)
2195 {
2196 struct broken_word *untruth;
2197 char *table_ptr;
2198 addressT table_addr;
2199 addressT from_addr, to_addr;
2200 int n, m;
2201
2202 subseg_change (lie->seg, lie->subseg);
2203 fragP = lie->dispfrag;
2204
2205 /* Find out how many broken_words go here. */
2206 n = 0;
2207 for (untruth = lie;
2208 untruth && untruth->dispfrag == fragP;
2209 untruth = untruth->next_broken_word)
2210 if (untruth->added == 1)
2211 n++;
2212
2213 table_ptr = lie->dispfrag->fr_opcode;
2214 table_addr = (lie->dispfrag->fr_address
2215 + (table_ptr - lie->dispfrag->fr_literal));
2216 /* Create the jump around the long jumps. This is a short
2217 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
2218 from_addr = table_addr;
2219 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
2220 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
2221 lie->add);
2222 table_ptr += md_short_jump_size;
2223 table_addr += md_short_jump_size;
2224
2225 for (m = 0;
2226 lie && lie->dispfrag == fragP;
2227 m++, lie = lie->next_broken_word)
2228 {
2229 if (lie->added == 2)
2230 continue;
2231 /* Patch the jump table. */
2232 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2233 untruth && untruth->dispfrag == fragP;
2234 untruth = untruth->next_broken_word)
2235 {
2236 if (untruth->use_jump == lie)
2237 {
2238 /* This is the offset from ??? to table_ptr+0.
2239 The target is the same for all users of this
2240 md_long_jump, but the "sub" bases (and hence the
2241 offsets) may be different. */
2242 addressT to_word = table_addr - S_GET_VALUE (untruth->sub);
2243 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
2244 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_word, untruth);
2245 #endif
2246 md_number_to_chars (untruth->word_goes_here, to_word, 2);
2247 }
2248 }
2249
2250 /* Install the long jump. */
2251 /* This is a long jump from table_ptr+0 to the final target. */
2252 from_addr = table_addr;
2253 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
2254 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
2255 lie->add);
2256 table_ptr += md_long_jump_size;
2257 table_addr += md_long_jump_size;
2258 }
2259 }
2260 }
2261 #endif /* not WORKING_DOT_WORD */
2262
2263 /* Resolve symbol values. This needs to be done before processing
2264 the relocations. */
2265 if (symbol_rootP)
2266 {
2267 symbolS *symp;
2268
2269 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
2270 resolve_symbol_value (symp);
2271 }
2272 resolve_local_symbol_values ();
2273 resolve_reloc_expr_symbols ();
2274
2275 #ifdef OBJ_ELF
2276 if (IS_ELF)
2277 maybe_generate_build_notes ();
2278 #endif
2279
2280 PROGRESS (1);
2281
2282 #ifdef tc_frob_file_before_adjust
2283 tc_frob_file_before_adjust ();
2284 #endif
2285 #ifdef obj_frob_file_before_adjust
2286 obj_frob_file_before_adjust ();
2287 #endif
2288
2289 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
2290
2291 #ifdef tc_frob_file_before_fix
2292 tc_frob_file_before_fix ();
2293 #endif
2294 #ifdef obj_frob_file_before_fix
2295 obj_frob_file_before_fix ();
2296 #endif
2297
2298 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
2299
2300 /* Set up symbol table, and write it out. */
2301 if (symbol_rootP)
2302 {
2303 symbolS *symp;
2304 bfd_boolean skip_next_symbol = FALSE;
2305
2306 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
2307 {
2308 int punt = 0;
2309 const char *name;
2310
2311 if (skip_next_symbol)
2312 {
2313 /* Don't do anything besides moving the value of the
2314 symbol from the GAS value-field to the BFD value-field. */
2315 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
2316 skip_next_symbol = FALSE;
2317 continue;
2318 }
2319
2320 if (symbol_mri_common_p (symp))
2321 {
2322 if (S_IS_EXTERNAL (symp))
2323 as_bad (_("%s: global symbols not supported in common sections"),
2324 S_GET_NAME (symp));
2325 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2326 continue;
2327 }
2328
2329 name = S_GET_NAME (symp);
2330 if (name)
2331 {
2332 const char *name2 =
2333 decode_local_label_name ((char *) S_GET_NAME (symp));
2334 /* They only differ if `name' is a fb or dollar local
2335 label name. */
2336 if (name2 != name && ! S_IS_DEFINED (symp))
2337 as_bad (_("local label `%s' is not defined"), name2);
2338 }
2339
2340 /* Do it again, because adjust_reloc_syms might introduce
2341 more symbols. They'll probably only be section symbols,
2342 but they'll still need to have the values computed. */
2343 resolve_symbol_value (symp);
2344
2345 /* Skip symbols which were equated to undefined or common
2346 symbols. */
2347 if (symbol_equated_reloc_p (symp)
2348 || S_IS_WEAKREFR (symp))
2349 {
2350 const char *sname = S_GET_NAME (symp);
2351
2352 if (S_IS_COMMON (symp)
2353 && !TC_FAKE_LABEL (sname)
2354 && !S_IS_WEAKREFR (symp))
2355 {
2356 expressionS *e = symbol_get_value_expression (symp);
2357
2358 as_bad (_("`%s' can't be equated to common symbol `%s'"),
2359 sname, S_GET_NAME (e->X_add_symbol));
2360 }
2361 if (S_GET_SEGMENT (symp) == reg_section)
2362 {
2363 /* Report error only if we know the symbol name. */
2364 if (S_GET_NAME (symp) != reg_section->name)
2365 as_bad (_("can't make global register symbol `%s'"),
2366 sname);
2367 }
2368 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2369 continue;
2370 }
2371
2372 #ifdef obj_frob_symbol
2373 obj_frob_symbol (symp, punt);
2374 #endif
2375 #ifdef tc_frob_symbol
2376 if (! punt || symbol_used_in_reloc_p (symp))
2377 tc_frob_symbol (symp, punt);
2378 #endif
2379
2380 /* If we don't want to keep this symbol, splice it out of
2381 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
2382 want section symbols. Otherwise, we skip local symbols
2383 and symbols that the frob_symbol macros told us to punt,
2384 but we keep such symbols if they are used in relocs. */
2385 if (symp == abs_section_sym
2386 || (! EMIT_SECTION_SYMBOLS
2387 && symbol_section_p (symp))
2388 /* Note that S_IS_EXTERNAL and S_IS_LOCAL are not always
2389 opposites. Sometimes the former checks flags and the
2390 latter examines the name... */
2391 || (!S_IS_EXTERNAL (symp)
2392 && (punt || S_IS_LOCAL (symp) ||
2393 (S_IS_WEAKREFD (symp) && ! symbol_used_p (symp)))
2394 && ! symbol_used_in_reloc_p (symp)))
2395 {
2396 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2397
2398 /* After symbol_remove, symbol_next(symp) still returns
2399 the one that came after it in the chain. So we don't
2400 need to do any extra cleanup work here. */
2401 continue;
2402 }
2403
2404 /* Make sure we really got a value for the symbol. */
2405 if (! symbol_resolved_p (symp))
2406 {
2407 as_bad (_("can't resolve value for symbol `%s'"),
2408 S_GET_NAME (symp));
2409 symbol_mark_resolved (symp);
2410 }
2411
2412 /* Set the value into the BFD symbol. Up til now the value
2413 has only been kept in the gas symbolS struct. */
2414 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
2415
2416 /* A warning construct is a warning symbol followed by the
2417 symbol warned about. Don't let anything object-format or
2418 target-specific muck with it; it's ready for output. */
2419 if (symbol_get_bfdsym (symp)->flags & BSF_WARNING)
2420 skip_next_symbol = TRUE;
2421 }
2422 }
2423
2424 PROGRESS (1);
2425
2426 /* Now do any format-specific adjustments to the symbol table, such
2427 as adding file symbols. */
2428 #ifdef tc_adjust_symtab
2429 tc_adjust_symtab ();
2430 #endif
2431 #ifdef obj_adjust_symtab
2432 obj_adjust_symtab ();
2433 #endif
2434
2435 /* Stop if there is an error. */
2436 if (had_errors ())
2437 return;
2438
2439 /* Now that all the sizes are known, and contents correct, we can
2440 start writing to the file. */
2441 set_symtab ();
2442
2443 /* If *_frob_file changes the symbol value at this point, it is
2444 responsible for moving the changed value into symp->bsym->value
2445 as well. Hopefully all symbol value changing can be done in
2446 *_frob_symbol. */
2447 #ifdef tc_frob_file
2448 tc_frob_file ();
2449 #endif
2450 #ifdef obj_frob_file
2451 obj_frob_file ();
2452 #endif
2453 #ifdef obj_coff_generate_pdata
2454 obj_coff_generate_pdata ();
2455 #endif
2456
2457 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
2458
2459 #ifdef tc_frob_file_after_relocs
2460 tc_frob_file_after_relocs ();
2461 #endif
2462 #ifdef obj_frob_file_after_relocs
2463 obj_frob_file_after_relocs ();
2464 #endif
2465
2466 #if defined OBJ_ELF || defined OBJ_MAYBE_ELF
2467 if (IS_ELF && flag_use_elf_stt_common)
2468 stdoutput->flags |= BFD_CONVERT_ELF_COMMON | BFD_USE_ELF_STT_COMMON;
2469 #endif
2470
2471 /* Once all relocations have been written, we can compress the
2472 contents of the debug sections. This needs to be done before
2473 we start writing any sections, because it will affect the file
2474 layout, which is fixed once we start writing contents. */
2475 if (flag_compress_debug)
2476 {
2477 if (flag_compress_debug == COMPRESS_DEBUG_GABI_ZLIB)
2478 stdoutput->flags |= BFD_COMPRESS | BFD_COMPRESS_GABI;
2479 else
2480 stdoutput->flags |= BFD_COMPRESS;
2481 bfd_map_over_sections (stdoutput, compress_debug, (char *) 0);
2482 }
2483
2484 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
2485 }
2486
2487 #ifdef TC_GENERIC_RELAX_TABLE
2488 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2489
2490 long
2491 relax_frag (segT segment, fragS *fragP, long stretch)
2492 {
2493 const relax_typeS *this_type;
2494 const relax_typeS *start_type;
2495 relax_substateT next_state;
2496 relax_substateT this_state;
2497 offsetT growth;
2498 offsetT aim;
2499 addressT target;
2500 addressT address;
2501 symbolS *symbolP;
2502 const relax_typeS *table;
2503
2504 target = fragP->fr_offset;
2505 address = fragP->fr_address;
2506 table = TC_GENERIC_RELAX_TABLE;
2507 this_state = fragP->fr_subtype;
2508 start_type = this_type = table + this_state;
2509 symbolP = fragP->fr_symbol;
2510
2511 if (symbolP)
2512 {
2513 fragS *sym_frag;
2514
2515 sym_frag = symbol_get_frag (symbolP);
2516
2517 #ifndef DIFF_EXPR_OK
2518 know (sym_frag != NULL);
2519 #endif
2520 know (S_GET_SEGMENT (symbolP) != absolute_section
2521 || sym_frag == &zero_address_frag);
2522 target += S_GET_VALUE (symbolP);
2523
2524 /* If SYM_FRAG has yet to be reached on this pass, assume it
2525 will move by STRETCH just as we did, unless there is an
2526 alignment frag between here and SYM_FRAG. An alignment may
2527 well absorb any STRETCH, and we don't want to choose a larger
2528 branch insn by overestimating the needed reach of this
2529 branch. It isn't critical to calculate TARGET exactly; We
2530 know we'll be doing another pass if STRETCH is non-zero. */
2531
2532 if (stretch != 0
2533 && sym_frag->relax_marker != fragP->relax_marker
2534 && S_GET_SEGMENT (symbolP) == segment)
2535 {
2536 if (stretch < 0
2537 || sym_frag->region == fragP->region)
2538 target += stretch;
2539 /* If we get here we know we have a forward branch. This
2540 relax pass may have stretched previous instructions so
2541 far that omitting STRETCH would make the branch
2542 negative. Don't allow this in case the negative reach is
2543 large enough to require a larger branch instruction. */
2544 else if (target < address)
2545 target = fragP->fr_next->fr_address + stretch;
2546 }
2547 }
2548
2549 aim = target - address - fragP->fr_fix;
2550 #ifdef TC_PCREL_ADJUST
2551 /* Currently only the ns32k family needs this. */
2552 aim += TC_PCREL_ADJUST (fragP);
2553 #endif
2554
2555 #ifdef md_prepare_relax_scan
2556 /* Formerly called M68K_AIM_KLUDGE. */
2557 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2558 #endif
2559
2560 if (aim < 0)
2561 {
2562 /* Look backwards. */
2563 for (next_state = this_type->rlx_more; next_state;)
2564 if (aim >= this_type->rlx_backward)
2565 next_state = 0;
2566 else
2567 {
2568 /* Grow to next state. */
2569 this_state = next_state;
2570 this_type = table + this_state;
2571 next_state = this_type->rlx_more;
2572 }
2573 }
2574 else
2575 {
2576 /* Look forwards. */
2577 for (next_state = this_type->rlx_more; next_state;)
2578 if (aim <= this_type->rlx_forward)
2579 next_state = 0;
2580 else
2581 {
2582 /* Grow to next state. */
2583 this_state = next_state;
2584 this_type = table + this_state;
2585 next_state = this_type->rlx_more;
2586 }
2587 }
2588
2589 growth = this_type->rlx_length - start_type->rlx_length;
2590 if (growth != 0)
2591 fragP->fr_subtype = this_state;
2592 return growth;
2593 }
2594
2595 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2596
2597 /* Relax_align. Advance location counter to next address that has 'alignment'
2598 lowest order bits all 0s, return size of adjustment made. */
2599 static relax_addressT
2600 relax_align (relax_addressT address, /* Address now. */
2601 int alignment /* Alignment (binary). */)
2602 {
2603 relax_addressT mask;
2604 relax_addressT new_address;
2605
2606 mask = ~((relax_addressT) ~0 << alignment);
2607 new_address = (address + mask) & (~mask);
2608 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2609 if (linkrelax)
2610 /* We must provide lots of padding, so the linker can discard it
2611 when needed. The linker will not add extra space, ever. */
2612 new_address += (1 << alignment);
2613 #endif
2614 return (new_address - address);
2615 }
2616
2617 /* Now we have a segment, not a crowd of sub-segments, we can make
2618 fr_address values.
2619
2620 Relax the frags.
2621
2622 After this, all frags in this segment have addresses that are correct
2623 within the segment. Since segments live in different file addresses,
2624 these frag addresses may not be the same as final object-file
2625 addresses. */
2626
2627 int
2628 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2629 {
2630 unsigned long frag_count;
2631 struct frag *fragP;
2632 relax_addressT address;
2633 int region;
2634 int ret;
2635
2636 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2637 subseg_change (segment, 0);
2638
2639 /* For each frag in segment: count and store (a 1st guess of)
2640 fr_address. */
2641 address = 0;
2642 region = 0;
2643 for (frag_count = 0, fragP = segment_frag_root;
2644 fragP;
2645 fragP = fragP->fr_next, frag_count ++)
2646 {
2647 fragP->region = region;
2648 fragP->relax_marker = 0;
2649 fragP->fr_address = address;
2650 address += fragP->fr_fix;
2651
2652 switch (fragP->fr_type)
2653 {
2654 case rs_fill:
2655 address += fragP->fr_offset * fragP->fr_var;
2656 break;
2657
2658 case rs_align:
2659 case rs_align_code:
2660 case rs_align_test:
2661 {
2662 addressT offset = relax_align (address, (int) fragP->fr_offset);
2663
2664 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2665 offset = 0;
2666
2667 if (offset % fragP->fr_var != 0)
2668 {
2669 as_bad_where (fragP->fr_file, fragP->fr_line,
2670 ngettext ("alignment padding (%lu byte) "
2671 "not a multiple of %ld",
2672 "alignment padding (%lu bytes) "
2673 "not a multiple of %ld",
2674 (unsigned long) offset),
2675 (unsigned long) offset, (long) fragP->fr_var);
2676 offset -= (offset % fragP->fr_var);
2677 }
2678
2679 address += offset;
2680 region += 1;
2681 }
2682 break;
2683
2684 case rs_org:
2685 /* Assume .org is nugatory. It will grow with 1st relax. */
2686 region += 1;
2687 break;
2688
2689 case rs_space:
2690 case rs_space_nop:
2691 break;
2692
2693 case rs_machine_dependent:
2694 /* If fr_symbol is an expression, this call to
2695 resolve_symbol_value sets up the correct segment, which will
2696 likely be needed in md_estimate_size_before_relax. */
2697 if (fragP->fr_symbol)
2698 resolve_symbol_value (fragP->fr_symbol);
2699
2700 address += md_estimate_size_before_relax (fragP, segment);
2701 break;
2702
2703 #ifndef WORKING_DOT_WORD
2704 /* Broken words don't concern us yet. */
2705 case rs_broken_word:
2706 break;
2707 #endif
2708
2709 case rs_leb128:
2710 /* Initial guess is always 1; doing otherwise can result in
2711 stable solutions that are larger than the minimum. */
2712 address += fragP->fr_offset = 1;
2713 break;
2714
2715 case rs_cfa:
2716 address += eh_frame_estimate_size_before_relax (fragP);
2717 break;
2718
2719 case rs_dwarf2dbg:
2720 address += dwarf2dbg_estimate_size_before_relax (fragP);
2721 break;
2722
2723 default:
2724 BAD_CASE (fragP->fr_type);
2725 break;
2726 }
2727 }
2728
2729 /* Do relax(). */
2730 {
2731 unsigned long max_iterations;
2732
2733 /* Cumulative address adjustment. */
2734 offsetT stretch;
2735
2736 /* Have we made any adjustment this pass? We can't just test
2737 stretch because one piece of code may have grown and another
2738 shrank. */
2739 int stretched;
2740
2741 /* Most horrible, but gcc may give us some exception data that
2742 is impossible to assemble, of the form
2743
2744 .align 4
2745 .byte 0, 0
2746 .uleb128 end - start
2747 start:
2748 .space 128*128 - 1
2749 .align 4
2750 end:
2751
2752 If the leb128 is two bytes in size, then end-start is 128*128,
2753 which requires a three byte leb128. If the leb128 is three
2754 bytes in size, then end-start is 128*128-1, which requires a
2755 two byte leb128. We work around this dilemma by inserting
2756 an extra 4 bytes of alignment just after the .align. This
2757 works because the data after the align is accessed relative to
2758 the end label.
2759
2760 This counter is used in a tiny state machine to detect
2761 whether a leb128 followed by an align is impossible to
2762 relax. */
2763 int rs_leb128_fudge = 0;
2764
2765 /* We want to prevent going into an infinite loop where one frag grows
2766 depending upon the location of a symbol which is in turn moved by
2767 the growing frag. eg:
2768
2769 foo = .
2770 .org foo+16
2771 foo = .
2772
2773 So we dictate that this algorithm can be at most O2. */
2774 max_iterations = frag_count * frag_count;
2775 /* Check for overflow. */
2776 if (max_iterations < frag_count)
2777 max_iterations = frag_count;
2778
2779 ret = 0;
2780 do
2781 {
2782 stretch = 0;
2783 stretched = 0;
2784
2785 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2786 {
2787 offsetT growth = 0;
2788 addressT was_address;
2789 offsetT offset;
2790 symbolS *symbolP;
2791
2792 fragP->relax_marker ^= 1;
2793 was_address = fragP->fr_address;
2794 address = fragP->fr_address += stretch;
2795 symbolP = fragP->fr_symbol;
2796 offset = fragP->fr_offset;
2797
2798 switch (fragP->fr_type)
2799 {
2800 case rs_fill: /* .fill never relaxes. */
2801 growth = 0;
2802 break;
2803
2804 #ifndef WORKING_DOT_WORD
2805 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2806 for it I do not want to write it. I do not want to have
2807 anything to do with it. This is not the proper way to
2808 implement this misfeature. */
2809 case rs_broken_word:
2810 {
2811 struct broken_word *lie;
2812 struct broken_word *untruth;
2813
2814 /* Yes this is ugly (storing the broken_word pointer
2815 in the symbol slot). Still, this whole chunk of
2816 code is ugly, and I don't feel like doing anything
2817 about it. Think of it as stubbornness in action. */
2818 growth = 0;
2819 for (lie = (struct broken_word *) (fragP->fr_symbol);
2820 lie && lie->dispfrag == fragP;
2821 lie = lie->next_broken_word)
2822 {
2823
2824 if (lie->added)
2825 continue;
2826
2827 offset = (S_GET_VALUE (lie->add)
2828 + lie->addnum
2829 - S_GET_VALUE (lie->sub));
2830 if (offset <= -32768 || offset >= 32767)
2831 {
2832 if (flag_warn_displacement)
2833 {
2834 char buf[50];
2835 sprint_value (buf, (addressT) lie->addnum);
2836 as_warn_where (fragP->fr_file, fragP->fr_line,
2837 _(".word %s-%s+%s didn't fit"),
2838 S_GET_NAME (lie->add),
2839 S_GET_NAME (lie->sub),
2840 buf);
2841 }
2842 if (fragP->fr_subtype == 0)
2843 {
2844 fragP->fr_subtype++;
2845 growth += md_short_jump_size;
2846 }
2847
2848 /* Redirect *all* words of this table with the same
2849 target, lest we have to handle the case where the
2850 same target but with a offset that fits on this
2851 round overflows at the next relaxation round. */
2852 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2853 untruth && untruth->dispfrag == lie->dispfrag;
2854 untruth = untruth->next_broken_word)
2855 if ((symbol_get_frag (untruth->add)
2856 == symbol_get_frag (lie->add))
2857 && (S_GET_VALUE (untruth->add)
2858 == S_GET_VALUE (lie->add)))
2859 {
2860 untruth->added = 2;
2861 untruth->use_jump = lie;
2862 }
2863
2864 lie->added = 1;
2865 growth += md_long_jump_size;
2866 }
2867 }
2868
2869 break;
2870 } /* case rs_broken_word */
2871 #endif
2872 case rs_align:
2873 case rs_align_code:
2874 case rs_align_test:
2875 {
2876 addressT oldoff, newoff;
2877
2878 oldoff = relax_align (was_address + fragP->fr_fix,
2879 (int) offset);
2880 newoff = relax_align (address + fragP->fr_fix,
2881 (int) offset);
2882
2883 if (fragP->fr_subtype != 0)
2884 {
2885 if (oldoff > fragP->fr_subtype)
2886 oldoff = 0;
2887 if (newoff > fragP->fr_subtype)
2888 newoff = 0;
2889 }
2890
2891 growth = newoff - oldoff;
2892
2893 /* If this align happens to follow a leb128 and
2894 we have determined that the leb128 is bouncing
2895 in size, then break the cycle by inserting an
2896 extra alignment. */
2897 if (growth < 0
2898 && (rs_leb128_fudge & 16) != 0
2899 && (rs_leb128_fudge & 15) >= 2)
2900 {
2901 segment_info_type *seginfo = seg_info (segment);
2902 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2903 struct frag *newf;
2904
2905 newf = frag_alloc (ob);
2906 obstack_blank_fast (ob, fragP->fr_var);
2907 obstack_finish (ob);
2908 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2909 memcpy (newf->fr_literal,
2910 fragP->fr_literal + fragP->fr_fix,
2911 fragP->fr_var);
2912 newf->fr_type = rs_fill;
2913 newf->fr_address = address + fragP->fr_fix + newoff;
2914 newf->fr_fix = 0;
2915 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2916 / fragP->fr_var);
2917 if (newf->fr_offset * newf->fr_var
2918 != (offsetT) 1 << fragP->fr_offset)
2919 {
2920 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2921 newf->fr_var = 1;
2922 }
2923 /* Include size of new frag in GROWTH. */
2924 growth += newf->fr_offset * newf->fr_var;
2925 /* Adjust the new frag address for the amount
2926 we'll add when we process the new frag. */
2927 newf->fr_address -= stretch + growth;
2928 newf->relax_marker ^= 1;
2929 fragP->fr_next = newf;
2930 #ifdef DEBUG
2931 as_warn (_("padding added"));
2932 #endif
2933 }
2934 }
2935 break;
2936
2937 case rs_org:
2938 {
2939 addressT target = offset;
2940 addressT after;
2941
2942 if (symbolP)
2943 {
2944 /* Convert from an actual address to an octet offset
2945 into the section. Here it is assumed that the
2946 section's VMA is zero, and can omit subtracting it
2947 from the symbol's value to get the address offset. */
2948 know (S_GET_SEGMENT (symbolP)->vma == 0);
2949 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2950 }
2951
2952 know (fragP->fr_next);
2953 after = fragP->fr_next->fr_address + stretch;
2954 growth = target - after;
2955
2956 /* Growth may be negative, but variable part of frag
2957 cannot have fewer than 0 chars. That is, we can't
2958 .org backwards. */
2959 if (address + fragP->fr_fix > target)
2960 {
2961 growth = 0;
2962
2963 /* Don't error on first few frag relax passes.
2964 The symbol might be an expression involving
2965 symbol values from other sections. If those
2966 sections have not yet been processed their
2967 frags will all have zero addresses, so we
2968 will calculate incorrect values for them. The
2969 number of passes we allow before giving an
2970 error is somewhat arbitrary. It should be at
2971 least one, with larger values requiring
2972 increasingly contrived dependencies between
2973 frags to trigger a false error. */
2974 if (pass < 2)
2975 {
2976 /* Force another pass. */
2977 ret = 1;
2978 break;
2979 }
2980
2981 as_bad_where (fragP->fr_file, fragP->fr_line,
2982 _("attempt to move .org backwards"));
2983
2984 /* We've issued an error message. Change the
2985 frag to avoid cascading errors. */
2986 fragP->fr_type = rs_align;
2987 fragP->fr_subtype = 0;
2988 fragP->fr_offset = 0;
2989 fragP->fr_fix = after - address;
2990 }
2991 }
2992 break;
2993
2994 case rs_space:
2995 case rs_space_nop:
2996 growth = 0;
2997 if (symbolP)
2998 {
2999 offsetT amount;
3000
3001 amount = S_GET_VALUE (symbolP);
3002 if (S_GET_SEGMENT (symbolP) != absolute_section
3003 || S_IS_COMMON (symbolP)
3004 || ! S_IS_DEFINED (symbolP))
3005 {
3006 as_bad_where (fragP->fr_file, fragP->fr_line,
3007 _(".space specifies non-absolute value"));
3008 /* Prevent repeat of this error message. */
3009 fragP->fr_symbol = 0;
3010 }
3011 else if (amount < 0)
3012 {
3013 /* Don't error on first few frag relax passes.
3014 See rs_org comment for a longer explanation. */
3015 if (pass < 2)
3016 {
3017 ret = 1;
3018 break;
3019 }
3020
3021 as_warn_where (fragP->fr_file, fragP->fr_line,
3022 _(".space, .nops or .fill with negative value, ignored"));
3023 fragP->fr_symbol = 0;
3024 }
3025 else
3026 growth = (was_address + fragP->fr_fix + amount
3027 - fragP->fr_next->fr_address);
3028 }
3029 break;
3030
3031 case rs_machine_dependent:
3032 #ifdef md_relax_frag
3033 growth = md_relax_frag (segment, fragP, stretch);
3034 #else
3035 #ifdef TC_GENERIC_RELAX_TABLE
3036 /* The default way to relax a frag is to look through
3037 TC_GENERIC_RELAX_TABLE. */
3038 growth = relax_frag (segment, fragP, stretch);
3039 #endif /* TC_GENERIC_RELAX_TABLE */
3040 #endif
3041 break;
3042
3043 case rs_leb128:
3044 {
3045 valueT value;
3046 offsetT size;
3047
3048 value = resolve_symbol_value (fragP->fr_symbol);
3049 size = sizeof_leb128 (value, fragP->fr_subtype);
3050 growth = size - fragP->fr_offset;
3051 fragP->fr_offset = size;
3052 }
3053 break;
3054
3055 case rs_cfa:
3056 growth = eh_frame_relax_frag (fragP);
3057 break;
3058
3059 case rs_dwarf2dbg:
3060 growth = dwarf2dbg_relax_frag (fragP);
3061 break;
3062
3063 default:
3064 BAD_CASE (fragP->fr_type);
3065 break;
3066 }
3067 if (growth)
3068 {
3069 stretch += growth;
3070 stretched = 1;
3071 if (fragP->fr_type == rs_leb128)
3072 rs_leb128_fudge += 16;
3073 else if (fragP->fr_type == rs_align
3074 && (rs_leb128_fudge & 16) != 0
3075 && stretch == 0)
3076 rs_leb128_fudge += 16;
3077 else
3078 rs_leb128_fudge = 0;
3079 }
3080 }
3081
3082 if (stretch == 0
3083 && (rs_leb128_fudge & 16) == 0
3084 && (rs_leb128_fudge & -16) != 0)
3085 rs_leb128_fudge += 1;
3086 else
3087 rs_leb128_fudge = 0;
3088 }
3089 /* Until nothing further to relax. */
3090 while (stretched && -- max_iterations);
3091
3092 if (stretched)
3093 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
3094 segment_name (segment));
3095 }
3096
3097 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
3098 if (fragP->last_fr_address != fragP->fr_address)
3099 {
3100 fragP->last_fr_address = fragP->fr_address;
3101 ret = 1;
3102 }
3103 return ret;
3104 }
3105
3106 void
3107 number_to_chars_bigendian (char *buf, valueT val, int n)
3108 {
3109 if (n <= 0)
3110 abort ();
3111 while (n--)
3112 {
3113 buf[n] = val & 0xff;
3114 val >>= 8;
3115 }
3116 }
3117
3118 void
3119 number_to_chars_littleendian (char *buf, valueT val, int n)
3120 {
3121 if (n <= 0)
3122 abort ();
3123 while (n--)
3124 {
3125 *buf++ = val & 0xff;
3126 val >>= 8;
3127 }
3128 }
3129
3130 void
3131 write_print_statistics (FILE *file)
3132 {
3133 fprintf (file, "fixups: %d\n", n_fixups);
3134 }
3135
3136 /* For debugging. */
3137 extern int indent_level;
3138
3139 void
3140 print_fixup (fixS *fixp)
3141 {
3142 indent_level = 1;
3143 fprintf (stderr, "fix ");
3144 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
3145 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
3146 if (fixp->fx_pcrel)
3147 fprintf (stderr, " pcrel");
3148 if (fixp->fx_pcrel_adjust)
3149 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
3150 if (fixp->fx_im_disp)
3151 {
3152 #ifdef TC_NS32K
3153 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
3154 #else
3155 fprintf (stderr, " im_disp");
3156 #endif
3157 }
3158 if (fixp->fx_tcbit)
3159 fprintf (stderr, " tcbit");
3160 if (fixp->fx_done)
3161 fprintf (stderr, " done");
3162 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
3163 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
3164 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
3165 (long) fixp->fx_where,
3166 (unsigned long) fixp->fx_offset,
3167 (unsigned long) fixp->fx_addnumber);
3168 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
3169 fixp->fx_r_type);
3170 if (fixp->fx_addsy)
3171 {
3172 fprintf (stderr, "\n +<");
3173 print_symbol_value_1 (stderr, fixp->fx_addsy);
3174 fprintf (stderr, ">");
3175 }
3176 if (fixp->fx_subsy)
3177 {
3178 fprintf (stderr, "\n -<");
3179 print_symbol_value_1 (stderr, fixp->fx_subsy);
3180 fprintf (stderr, ">");
3181 }
3182 fprintf (stderr, "\n");
3183 #ifdef TC_FIX_DATA_PRINT
3184 TC_FIX_DATA_PRINT (stderr, fixp);
3185 #endif
3186 }