d5da41850cc428bb4f716f079de339b7dbb1f8ff
[deliverable/binutils-gdb.git] / gas / write.c
1 /* write.c - emit .o file
2 Copyright (C) 1986-2019 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 unsigned long where, /* Where in that frag? */
147 unsigned long 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 %lu"), 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_pcrel_adjust = 0;
178 fixP->fx_addnumber = 0;
179 fixP->fx_tcbit = 0;
180 fixP->fx_tcbit2 = 0;
181 fixP->fx_done = 0;
182 fixP->fx_no_overflow = 0;
183 fixP->fx_signed = 0;
184
185 #ifdef USING_CGEN
186 fixP->fx_cgen.insn = NULL;
187 fixP->fx_cgen.opinfo = 0;
188 #endif
189
190 #ifdef TC_FIX_TYPE
191 TC_INIT_FIX_DATA (fixP);
192 #endif
193
194 fixP->fx_file = as_where (&fixP->fx_line);
195
196 {
197
198 fixS **seg_fix_rootP = (frags_chained
199 ? &seg_info (now_seg)->fix_root
200 : &frchain_now->fix_root);
201 fixS **seg_fix_tailP = (frags_chained
202 ? &seg_info (now_seg)->fix_tail
203 : &frchain_now->fix_tail);
204
205 if (at_beginning)
206 {
207 fixP->fx_next = *seg_fix_rootP;
208 *seg_fix_rootP = fixP;
209 if (fixP->fx_next == NULL)
210 *seg_fix_tailP = fixP;
211 }
212 else
213 {
214 fixP->fx_next = NULL;
215 if (*seg_fix_tailP)
216 (*seg_fix_tailP)->fx_next = fixP;
217 else
218 *seg_fix_rootP = fixP;
219 *seg_fix_tailP = fixP;
220 }
221 }
222
223 return fixP;
224 }
225
226 /* Create a fixup relative to a symbol (plus a constant). */
227
228 fixS *
229 fix_new (fragS *frag, /* Which frag? */
230 unsigned long where, /* Where in that frag? */
231 unsigned long size, /* 1, 2, or 4 usually. */
232 symbolS *add_symbol, /* X_add_symbol. */
233 offsetT offset, /* X_add_number. */
234 int pcrel, /* TRUE if PC-relative relocation. */
235 RELOC_ENUM r_type /* Relocation type. */)
236 {
237 return fix_new_internal (frag, where, size, add_symbol,
238 (symbolS *) NULL, offset, pcrel, r_type, FALSE);
239 }
240
241 /* Create a fixup for an expression. Currently we only support fixups
242 for difference expressions. That is itself more than most object
243 file formats support anyhow. */
244
245 fixS *
246 fix_new_exp (fragS *frag, /* Which frag? */
247 unsigned long where, /* Where in that frag? */
248 unsigned long size, /* 1, 2, or 4 usually. */
249 expressionS *exp, /* Expression. */
250 int pcrel, /* TRUE if PC-relative relocation. */
251 RELOC_ENUM r_type /* Relocation type. */)
252 {
253 symbolS *add = NULL;
254 symbolS *sub = NULL;
255 offsetT off = 0;
256
257 switch (exp->X_op)
258 {
259 case O_absent:
260 break;
261
262 case O_register:
263 as_bad (_("register value used as expression"));
264 break;
265
266 case O_add:
267 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
268 the difference expression cannot immediately be reduced. */
269 {
270 symbolS *stmp = make_expr_symbol (exp);
271
272 exp->X_op = O_symbol;
273 exp->X_op_symbol = 0;
274 exp->X_add_symbol = stmp;
275 exp->X_add_number = 0;
276
277 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
278 }
279
280 case O_symbol_rva:
281 add = exp->X_add_symbol;
282 off = exp->X_add_number;
283 r_type = BFD_RELOC_RVA;
284 break;
285
286 case O_uminus:
287 sub = exp->X_add_symbol;
288 off = exp->X_add_number;
289 break;
290
291 case O_subtract:
292 sub = exp->X_op_symbol;
293 /* Fall through. */
294 case O_symbol:
295 add = exp->X_add_symbol;
296 /* Fall through. */
297 case O_constant:
298 off = exp->X_add_number;
299 break;
300
301 default:
302 add = make_expr_symbol (exp);
303 break;
304 }
305
306 return fix_new_internal (frag, where, size, add, sub, off, pcrel,
307 r_type, FALSE);
308 }
309
310 /* Create a fixup at the beginning of FRAG. The arguments are the same
311 as for fix_new, except that WHERE is implicitly 0. */
312
313 fixS *
314 fix_at_start (fragS *frag, unsigned long size, symbolS *add_symbol,
315 offsetT offset, int pcrel, RELOC_ENUM r_type)
316 {
317 return fix_new_internal (frag, 0, size, add_symbol,
318 (symbolS *) NULL, offset, pcrel, r_type, TRUE);
319 }
320
321 /* Generic function to determine whether a fixup requires a relocation. */
322 int
323 generic_force_reloc (fixS *fix)
324 {
325 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
326 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
327 return 1;
328
329 if (fix->fx_addsy == NULL)
330 return 0;
331
332 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
333 }
334
335 /* Append a string onto another string, bumping the pointer along. */
336 void
337 append (char **charPP, char *fromP, unsigned long length)
338 {
339 /* Don't trust memcpy() of 0 chars. */
340 if (length == 0)
341 return;
342
343 memcpy (*charPP, fromP, length);
344 *charPP += length;
345 }
346
347 /* This routine records the largest alignment seen for each segment.
348 If the beginning of the segment is aligned on the worst-case
349 boundary, all of the other alignments within it will work. At
350 least one object format really uses this info. */
351
352 void
353 record_alignment (/* Segment to which alignment pertains. */
354 segT seg,
355 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
356 boundary, 2 => 4-byte boundary, etc.) */
357 unsigned int align)
358 {
359 if (seg == absolute_section)
360 return;
361
362 if (align > bfd_section_alignment (seg))
363 bfd_set_section_alignment (seg, align);
364 }
365
366 int
367 get_recorded_alignment (segT seg)
368 {
369 if (seg == absolute_section)
370 return 0;
371
372 return bfd_section_alignment (seg);
373 }
374
375 /* Reset the section indices after removing the gas created sections. */
376
377 static void
378 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *countparg)
379 {
380 int *countp = (int *) countparg;
381
382 sec->index = *countp;
383 ++*countp;
384 }
385
386 static fragS *
387 chain_frchains_together_1 (segT section, struct frchain *frchp)
388 {
389 fragS dummy, *prev_frag = &dummy;
390 fixS fix_dummy, *prev_fix = &fix_dummy;
391
392 for (; frchp; frchp = frchp->frch_next)
393 {
394 prev_frag->fr_next = frchp->frch_root;
395 prev_frag = frchp->frch_last;
396 gas_assert (prev_frag->fr_type != 0);
397 if (frchp->fix_root != (fixS *) NULL)
398 {
399 if (seg_info (section)->fix_root == (fixS *) NULL)
400 seg_info (section)->fix_root = frchp->fix_root;
401 prev_fix->fx_next = frchp->fix_root;
402 seg_info (section)->fix_tail = frchp->fix_tail;
403 prev_fix = frchp->fix_tail;
404 }
405 }
406 gas_assert (prev_frag != &dummy
407 && prev_frag->fr_type != 0);
408 prev_frag->fr_next = 0;
409 return prev_frag;
410 }
411
412 static void
413 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
414 segT section,
415 void *xxx ATTRIBUTE_UNUSED)
416 {
417 segment_info_type *info;
418
419 /* BFD may have introduced its own sections without using
420 subseg_new, so it is possible that seg_info is NULL. */
421 info = seg_info (section);
422 if (info != (segment_info_type *) NULL)
423 info->frchainP->frch_last
424 = chain_frchains_together_1 (section, info->frchainP);
425
426 /* Now that we've chained the frags together, we must add new fixups
427 to the segment, not to the frag chain. */
428 frags_chained = 1;
429 }
430
431 static void
432 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
433 {
434 switch (fragP->fr_type)
435 {
436 case rs_space_nop:
437 goto skip_align;
438 case rs_align:
439 case rs_align_code:
440 case rs_align_test:
441 case rs_org:
442 case rs_space:
443 #ifdef HANDLE_ALIGN
444 HANDLE_ALIGN (fragP);
445 #endif
446 skip_align:
447 know (fragP->fr_next != NULL);
448 fragP->fr_offset = (fragP->fr_next->fr_address
449 - fragP->fr_address
450 - fragP->fr_fix) / fragP->fr_var;
451 if (fragP->fr_offset < 0)
452 {
453 as_bad_where (fragP->fr_file, fragP->fr_line,
454 _("attempt to .org/.space/.nops backwards? (%ld)"),
455 (long) fragP->fr_offset);
456 fragP->fr_offset = 0;
457 }
458 if (fragP->fr_type == rs_space_nop)
459 fragP->fr_type = rs_fill_nop;
460 else
461 fragP->fr_type = rs_fill;
462 break;
463
464 case rs_fill:
465 case rs_fill_nop:
466 break;
467
468 case rs_leb128:
469 {
470 valueT value = S_GET_VALUE (fragP->fr_symbol);
471 int size;
472
473 if (!S_IS_DEFINED (fragP->fr_symbol))
474 {
475 as_bad_where (fragP->fr_file, fragP->fr_line,
476 _("leb128 operand is an undefined symbol: %s"),
477 S_GET_NAME (fragP->fr_symbol));
478 }
479
480 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
481 fragP->fr_subtype);
482
483 fragP->fr_fix += size;
484 fragP->fr_type = rs_fill;
485 fragP->fr_var = 0;
486 fragP->fr_offset = 0;
487 fragP->fr_symbol = NULL;
488 }
489 break;
490
491 case rs_cfa:
492 eh_frame_convert_frag (fragP);
493 break;
494
495 case rs_dwarf2dbg:
496 dwarf2dbg_convert_frag (fragP);
497 break;
498
499 case rs_machine_dependent:
500 md_convert_frag (stdoutput, sec, fragP);
501
502 gas_assert (fragP->fr_next == NULL
503 || (fragP->fr_next->fr_address - fragP->fr_address
504 == fragP->fr_fix));
505
506 /* After md_convert_frag, we make the frag into a ".space 0".
507 md_convert_frag() should set up any fixSs and constants
508 required. */
509 frag_wane (fragP);
510 break;
511
512 #ifndef WORKING_DOT_WORD
513 case rs_broken_word:
514 {
515 struct broken_word *lie;
516
517 if (fragP->fr_subtype)
518 {
519 fragP->fr_fix += md_short_jump_size;
520 for (lie = (struct broken_word *) (fragP->fr_symbol);
521 lie && lie->dispfrag == fragP;
522 lie = lie->next_broken_word)
523 if (lie->added == 1)
524 fragP->fr_fix += md_long_jump_size;
525 }
526 frag_wane (fragP);
527 }
528 break;
529 #endif
530
531 default:
532 BAD_CASE (fragP->fr_type);
533 break;
534 }
535 #ifdef md_frag_check
536 md_frag_check (fragP);
537 #endif
538 }
539
540 struct relax_seg_info
541 {
542 int pass;
543 int changed;
544 };
545
546 static void
547 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx)
548 {
549 segment_info_type *seginfo = seg_info (sec);
550 struct relax_seg_info *info = (struct relax_seg_info *) xxx;
551
552 if (seginfo && seginfo->frchainP
553 && relax_segment (seginfo->frchainP->frch_root, sec, info->pass))
554 info->changed = 1;
555 }
556
557 static void
558 size_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx ATTRIBUTE_UNUSED)
559 {
560 flagword flags;
561 fragS *fragp;
562 segment_info_type *seginfo;
563 int x;
564 valueT size, newsize;
565
566 subseg_change (sec, 0);
567
568 seginfo = seg_info (sec);
569 if (seginfo && seginfo->frchainP)
570 {
571 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
572 cvt_frag_to_fill (sec, fragp);
573 for (fragp = seginfo->frchainP->frch_root;
574 fragp->fr_next;
575 fragp = fragp->fr_next)
576 /* Walk to last elt. */
577 ;
578 size = fragp->fr_address + fragp->fr_fix;
579 }
580 else
581 size = 0;
582
583 flags = bfd_section_flags (sec);
584 if (size == 0 && bfd_section_size (sec) != 0 &&
585 (flags & SEC_HAS_CONTENTS) != 0)
586 return;
587
588 if (size > 0 && ! seginfo->bss)
589 flags |= SEC_HAS_CONTENTS;
590
591 flags &= ~SEC_RELOC;
592 x = bfd_set_section_flags (sec, flags);
593 gas_assert (x);
594
595 /* If permitted, allow the backend to pad out the section
596 to some alignment boundary. */
597 if (do_not_pad_sections_to_alignment)
598 newsize = size;
599 else
600 newsize = md_section_align (sec, size);
601 x = bfd_set_section_size (sec, newsize);
602 gas_assert (x);
603
604 /* If the size had to be rounded up, add some padding in the last
605 non-empty frag. */
606 gas_assert (newsize >= size);
607 if (size != newsize)
608 {
609 fragS *last = seginfo->frchainP->frch_last;
610 fragp = seginfo->frchainP->frch_root;
611 while (fragp->fr_next != last)
612 fragp = fragp->fr_next;
613 last->fr_address = size;
614 if ((newsize - size) % fragp->fr_var == 0)
615 fragp->fr_offset += (newsize - size) / fragp->fr_var;
616 else
617 /* If we hit this abort, it's likely due to subsegs_finish not
618 providing sufficient alignment on the last frag, and the
619 machine dependent code using alignment frags with fr_var
620 greater than 1. */
621 abort ();
622 }
623
624 #ifdef tc_frob_section
625 tc_frob_section (sec);
626 #endif
627 #ifdef obj_frob_section
628 obj_frob_section (sec);
629 #endif
630 }
631
632 #ifdef DEBUG2
633 static void
634 dump_section_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, FILE *stream)
635 {
636 segment_info_type *seginfo = seg_info (sec);
637 fixS *fixp = seginfo->fix_root;
638
639 if (!fixp)
640 return;
641
642 fprintf (stream, "sec %s relocs:\n", sec->name);
643 while (fixp)
644 {
645 symbolS *s = fixp->fx_addsy;
646
647 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
648 (int) fixp->fx_r_type);
649 if (s == NULL)
650 fprintf (stream, "no sym\n");
651 else
652 {
653 print_symbol_value_1 (stream, s);
654 fprintf (stream, "\n");
655 }
656 fixp = fixp->fx_next;
657 }
658 }
659 #else
660 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
661 #endif
662
663 #ifndef EMIT_SECTION_SYMBOLS
664 #define EMIT_SECTION_SYMBOLS 1
665 #endif
666
667 /* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
668 and check for validity. Convert RELOC_LIST from using U.A fields
669 to U.B fields. */
670 static void
671 resolve_reloc_expr_symbols (void)
672 {
673 bfd_vma addr_mask = 1;
674 struct reloc_list *r;
675
676 /* Avoid a shift by the width of type. */
677 addr_mask <<= bfd_arch_bits_per_address (stdoutput) - 1;
678 addr_mask <<= 1;
679 addr_mask -= 1;
680
681 for (r = reloc_list; r; r = r->next)
682 {
683 reloc_howto_type *howto = r->u.a.howto;
684 expressionS *symval;
685 symbolS *sym;
686 bfd_vma offset, addend;
687 asection *sec;
688
689 resolve_symbol_value (r->u.a.offset_sym);
690 symval = symbol_get_value_expression (r->u.a.offset_sym);
691
692 offset = 0;
693 sym = NULL;
694 if (symval->X_op == O_constant)
695 sym = r->u.a.offset_sym;
696 else if (symval->X_op == O_symbol)
697 {
698 sym = symval->X_add_symbol;
699 offset = symval->X_add_number;
700 symval = symbol_get_value_expression (symval->X_add_symbol);
701 }
702 if (sym == NULL
703 || symval->X_op != O_constant
704 || (sec = S_GET_SEGMENT (sym)) == NULL
705 || !SEG_NORMAL (sec))
706 {
707 as_bad_where (r->file, r->line, _("invalid offset expression"));
708 sec = NULL;
709 }
710 else
711 offset += S_GET_VALUE (sym);
712
713 sym = NULL;
714 addend = r->u.a.addend;
715 if (r->u.a.sym != NULL)
716 {
717 resolve_symbol_value (r->u.a.sym);
718 symval = symbol_get_value_expression (r->u.a.sym);
719 if (symval->X_op == O_constant)
720 sym = r->u.a.sym;
721 else if (symval->X_op == O_symbol)
722 {
723 sym = symval->X_add_symbol;
724 addend += symval->X_add_number;
725 symval = symbol_get_value_expression (symval->X_add_symbol);
726 }
727 if (symval->X_op != O_constant)
728 {
729 as_bad_where (r->file, r->line, _("invalid reloc expression"));
730 sec = NULL;
731 }
732 else if (sym != NULL && sec != NULL)
733 {
734 /* Convert relocs against local symbols to refer to the
735 corresponding section symbol plus offset instead. Keep
736 PC-relative relocs of the REL variety intact though to
737 prevent the offset from overflowing the relocated field,
738 unless it has enough bits to cover the whole address
739 space. */
740 if (S_IS_LOCAL (sym) && !symbol_section_p (sym)
741 && (sec->use_rela_p
742 || (howto->partial_inplace
743 && (!howto->pc_relative
744 || howto->src_mask == addr_mask))))
745 {
746 asection *symsec = S_GET_SEGMENT (sym);
747 if (!(((symsec->flags & SEC_MERGE) != 0
748 && addend != 0)
749 || (symsec->flags & SEC_THREAD_LOCAL) != 0))
750 {
751 addend += S_GET_VALUE (sym);
752 sym = section_symbol (symsec);
753 }
754 }
755 symbol_mark_used_in_reloc (sym);
756 }
757 }
758 if (sym == NULL)
759 {
760 if (abs_section_sym == NULL)
761 abs_section_sym = section_symbol (absolute_section);
762 sym = abs_section_sym;
763 }
764
765 r->u.b.sec = sec;
766 r->u.b.s = symbol_get_bfdsym (sym);
767 r->u.b.r.sym_ptr_ptr = &r->u.b.s;
768 r->u.b.r.address = offset;
769 r->u.b.r.addend = addend;
770 r->u.b.r.howto = howto;
771 }
772 }
773
774 /* This pass over fixups decides whether symbols can be replaced with
775 section symbols. */
776
777 static void
778 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
779 asection *sec,
780 void *xxx ATTRIBUTE_UNUSED)
781 {
782 segment_info_type *seginfo = seg_info (sec);
783 fixS *fixp;
784
785 if (seginfo == NULL)
786 return;
787
788 dump_section_relocs (abfd, sec, stderr);
789
790 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
791 if (fixp->fx_done)
792 /* Ignore it. */
793 ;
794 else if (fixp->fx_addsy)
795 {
796 symbolS *sym;
797 asection *symsec;
798
799 #ifdef DEBUG5
800 fprintf (stderr, "\n\nadjusting fixup:\n");
801 print_fixup (fixp);
802 #endif
803
804 sym = fixp->fx_addsy;
805
806 /* All symbols should have already been resolved at this
807 point. It is possible to see unresolved expression
808 symbols, though, since they are not in the regular symbol
809 table. */
810 resolve_symbol_value (sym);
811
812 if (fixp->fx_subsy != NULL)
813 resolve_symbol_value (fixp->fx_subsy);
814
815 /* If this symbol is equated to an undefined or common symbol,
816 convert the fixup to being against that symbol. */
817 while (symbol_equated_reloc_p (sym)
818 || S_IS_WEAKREFR (sym))
819 {
820 symbolS *newsym = symbol_get_value_expression (sym)->X_add_symbol;
821 if (sym == newsym)
822 break;
823 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
824 fixp->fx_addsy = newsym;
825 sym = newsym;
826 }
827
828 if (symbol_mri_common_p (sym))
829 {
830 fixp->fx_offset += S_GET_VALUE (sym);
831 fixp->fx_addsy = symbol_get_value_expression (sym)->X_add_symbol;
832 continue;
833 }
834
835 /* If the symbol is undefined, common, weak, or global (ELF
836 shared libs), we can't replace it with the section symbol. */
837 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
838 continue;
839
840 /* Is there some other (target cpu dependent) reason we can't adjust
841 this one? (E.g. relocations involving function addresses on
842 the PA. */
843 #ifdef tc_fix_adjustable
844 if (! tc_fix_adjustable (fixp))
845 continue;
846 #endif
847
848 /* Since we're reducing to section symbols, don't attempt to reduce
849 anything that's already using one. */
850 if (symbol_section_p (sym))
851 continue;
852
853 symsec = S_GET_SEGMENT (sym);
854 if (symsec == NULL)
855 abort ();
856
857 if (bfd_is_abs_section (symsec)
858 || symsec == reg_section)
859 {
860 /* The fixup_segment routine normally will not use this
861 symbol in a relocation. */
862 continue;
863 }
864
865 /* Don't try to reduce relocs which refer to non-local symbols
866 in .linkonce sections. It can lead to confusion when a
867 debugging section refers to a .linkonce section. I hope
868 this will always be correct. */
869 if (symsec != sec && ! S_IS_LOCAL (sym))
870 {
871 if ((symsec->flags & SEC_LINK_ONCE) != 0
872 || (IS_ELF
873 /* The GNU toolchain uses an extension for ELF: a
874 section beginning with the magic string
875 .gnu.linkonce is a linkonce section. */
876 && strncmp (segment_name (symsec), ".gnu.linkonce",
877 sizeof ".gnu.linkonce" - 1) == 0))
878 continue;
879 }
880
881 /* Never adjust a reloc against local symbol in a merge section
882 with non-zero addend. */
883 if ((symsec->flags & SEC_MERGE) != 0
884 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
885 continue;
886
887 /* Never adjust a reloc against TLS local symbol. */
888 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
889 continue;
890
891 /* We refetch the segment when calling section_symbol, rather
892 than using symsec, because S_GET_VALUE may wind up changing
893 the section when it calls resolve_symbol_value. */
894 fixp->fx_offset += S_GET_VALUE (sym);
895 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
896 #ifdef DEBUG5
897 fprintf (stderr, "\nadjusted fixup:\n");
898 print_fixup (fixp);
899 #endif
900 }
901
902 dump_section_relocs (abfd, sec, stderr);
903 }
904
905 /* fixup_segment()
906
907 Go through all the fixS's in a segment and see which ones can be
908 handled now. (These consist of fixS where we have since discovered
909 the value of a symbol, or the address of the frag involved.)
910 For each one, call md_apply_fix to put the fix into the frag data.
911 Ones that we couldn't completely handle here will be output later
912 by emit_relocations. */
913
914 static void
915 fixup_segment (fixS *fixP, segT this_segment)
916 {
917 valueT add_number;
918 fragS *fragP;
919 segT add_symbol_segment = absolute_section;
920
921 if (fixP != NULL && abs_section_sym == NULL)
922 abs_section_sym = section_symbol (absolute_section);
923
924 /* If the linker is doing the relaxing, we must not do any fixups.
925
926 Well, strictly speaking that's not true -- we could do any that
927 are PC-relative and don't cross regions that could change size. */
928 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
929 {
930 for (; fixP; fixP = fixP->fx_next)
931 if (!fixP->fx_done)
932 {
933 if (fixP->fx_addsy == NULL)
934 {
935 /* There was no symbol required by this relocation.
936 However, BFD doesn't really handle relocations
937 without symbols well. So fake up a local symbol in
938 the absolute section. */
939 fixP->fx_addsy = abs_section_sym;
940 }
941 symbol_mark_used_in_reloc (fixP->fx_addsy);
942 if (fixP->fx_subsy != NULL)
943 symbol_mark_used_in_reloc (fixP->fx_subsy);
944 }
945 return;
946 }
947
948 for (; fixP; fixP = fixP->fx_next)
949 {
950 #ifdef DEBUG5
951 fprintf (stderr, "\nprocessing fixup:\n");
952 print_fixup (fixP);
953 #endif
954
955 fragP = fixP->fx_frag;
956 know (fragP);
957 #ifdef TC_VALIDATE_FIX
958 TC_VALIDATE_FIX (fixP, this_segment, skip);
959 #endif
960 add_number = fixP->fx_offset;
961
962 if (fixP->fx_addsy != NULL)
963 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
964
965 if (fixP->fx_subsy != NULL)
966 {
967 segT sub_symbol_segment;
968 resolve_symbol_value (fixP->fx_subsy);
969 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
970 if (fixP->fx_addsy != NULL
971 && sub_symbol_segment == add_symbol_segment
972 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
973 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
974 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
975 {
976 add_number += S_GET_VALUE (fixP->fx_addsy);
977 add_number -= S_GET_VALUE (fixP->fx_subsy);
978 fixP->fx_offset = add_number;
979 fixP->fx_addsy = NULL;
980 fixP->fx_subsy = NULL;
981 #ifdef TC_M68K
982 /* See the comment below about 68k weirdness. */
983 fixP->fx_pcrel = 0;
984 #endif
985 }
986 else if (sub_symbol_segment == absolute_section
987 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
988 && !TC_FORCE_RELOCATION_SUB_ABS (fixP, add_symbol_segment))
989 {
990 add_number -= S_GET_VALUE (fixP->fx_subsy);
991 fixP->fx_offset = add_number;
992 fixP->fx_subsy = NULL;
993 }
994 else if (sub_symbol_segment == this_segment
995 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
996 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP, add_symbol_segment))
997 {
998 add_number -= S_GET_VALUE (fixP->fx_subsy);
999 fixP->fx_offset = (add_number + fixP->fx_dot_value
1000 + fixP->fx_dot_frag->fr_address);
1001
1002 /* Make it pc-relative. If the back-end code has not
1003 selected a pc-relative reloc, cancel the adjustment
1004 we do later on all pc-relative relocs. */
1005 if (0
1006 #ifdef TC_M68K
1007 /* Do this for m68k even if it's already described
1008 as pc-relative. On the m68k, an operand of
1009 "pc@(foo-.-2)" should address "foo" in a
1010 pc-relative mode. */
1011 || 1
1012 #endif
1013 || !fixP->fx_pcrel)
1014 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
1015 fixP->fx_subsy = NULL;
1016 fixP->fx_pcrel = 1;
1017 }
1018 else if (!TC_VALIDATE_FIX_SUB (fixP, add_symbol_segment))
1019 {
1020 if (!md_register_arithmetic
1021 && (add_symbol_segment == reg_section
1022 || sub_symbol_segment == reg_section))
1023 as_bad_where (fixP->fx_file, fixP->fx_line,
1024 _("register value used as expression"));
1025 else
1026 as_bad_where (fixP->fx_file, fixP->fx_line,
1027 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
1028 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
1029 segment_name (add_symbol_segment),
1030 S_GET_NAME (fixP->fx_subsy),
1031 segment_name (sub_symbol_segment));
1032 }
1033 else if (sub_symbol_segment != undefined_section
1034 && ! bfd_is_com_section (sub_symbol_segment)
1035 && MD_APPLY_SYM_VALUE (fixP))
1036 add_number -= S_GET_VALUE (fixP->fx_subsy);
1037 }
1038
1039 if (fixP->fx_addsy)
1040 {
1041 if (add_symbol_segment == this_segment
1042 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1043 && !TC_FORCE_RELOCATION_LOCAL (fixP))
1044 {
1045 /* This fixup was made when the symbol's segment was
1046 SEG_UNKNOWN, but it is now in the local segment.
1047 So we know how to do the address without relocation. */
1048 add_number += S_GET_VALUE (fixP->fx_addsy);
1049 fixP->fx_offset = add_number;
1050 if (fixP->fx_pcrel)
1051 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1052 fixP->fx_addsy = NULL;
1053 fixP->fx_pcrel = 0;
1054 }
1055 else if (add_symbol_segment == absolute_section
1056 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1057 && !TC_FORCE_RELOCATION_ABS (fixP))
1058 {
1059 add_number += S_GET_VALUE (fixP->fx_addsy);
1060 fixP->fx_offset = add_number;
1061 fixP->fx_addsy = NULL;
1062 }
1063 else if (add_symbol_segment != undefined_section
1064 && ! bfd_is_com_section (add_symbol_segment)
1065 && MD_APPLY_SYM_VALUE (fixP))
1066 add_number += S_GET_VALUE (fixP->fx_addsy);
1067 }
1068
1069 if (fixP->fx_pcrel)
1070 {
1071 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1072 if (!fixP->fx_done && fixP->fx_addsy == NULL)
1073 {
1074 /* There was no symbol required by this relocation.
1075 However, BFD doesn't really handle relocations
1076 without symbols well. So fake up a local symbol in
1077 the absolute section. */
1078 fixP->fx_addsy = abs_section_sym;
1079 }
1080 }
1081
1082 if (!fixP->fx_done)
1083 md_apply_fix (fixP, &add_number, this_segment);
1084
1085 if (!fixP->fx_done)
1086 {
1087 if (fixP->fx_addsy == NULL)
1088 fixP->fx_addsy = abs_section_sym;
1089 symbol_mark_used_in_reloc (fixP->fx_addsy);
1090 if (fixP->fx_subsy != NULL)
1091 symbol_mark_used_in_reloc (fixP->fx_subsy);
1092 }
1093
1094 if (!fixP->fx_no_overflow && fixP->fx_size != 0)
1095 {
1096 if (fixP->fx_size < sizeof (valueT))
1097 {
1098 valueT mask;
1099
1100 mask = 0;
1101 mask--; /* Set all bits to one. */
1102 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
1103 if ((add_number & mask) != 0 && (add_number & mask) != mask)
1104 {
1105 char buf[50], buf2[50];
1106 sprint_value (buf, fragP->fr_address + fixP->fx_where);
1107 if (add_number > 1000)
1108 sprint_value (buf2, add_number);
1109 else
1110 sprintf (buf2, "%ld", (long) add_number);
1111 as_bad_where (fixP->fx_file, fixP->fx_line,
1112 ngettext ("value of %s too large for field "
1113 "of %d byte at %s",
1114 "value of %s too large for field "
1115 "of %d bytes at %s",
1116 fixP->fx_size),
1117 buf2, fixP->fx_size, buf);
1118 } /* Generic error checking. */
1119 }
1120 #ifdef WARN_SIGNED_OVERFLOW_WORD
1121 /* Warn if a .word value is too large when treated as a signed
1122 number. We already know it is not too negative. This is to
1123 catch over-large switches generated by gcc on the 68k. */
1124 if (!flag_signed_overflow_ok
1125 && fixP->fx_size == 2
1126 && add_number > 0x7fff)
1127 as_bad_where (fixP->fx_file, fixP->fx_line,
1128 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
1129 (long) add_number,
1130 (long) (fragP->fr_address + fixP->fx_where));
1131 #endif
1132 }
1133
1134 #ifdef TC_VALIDATE_FIX
1135 skip: ATTRIBUTE_UNUSED_LABEL
1136 ;
1137 #endif
1138 #ifdef DEBUG5
1139 fprintf (stderr, "result:\n");
1140 print_fixup (fixP);
1141 #endif
1142 } /* For each fixS in this segment. */
1143 }
1144
1145 static void
1146 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
1147 asection *sec,
1148 void *xxx ATTRIBUTE_UNUSED)
1149 {
1150 segment_info_type *seginfo = seg_info (sec);
1151
1152 fixup_segment (seginfo->fix_root, sec);
1153 }
1154
1155 static void
1156 install_reloc (asection *sec, arelent *reloc, fragS *fragp,
1157 const char *file, unsigned int line)
1158 {
1159 char *err;
1160 bfd_reloc_status_type s;
1161 asymbol *sym;
1162
1163 if (reloc->sym_ptr_ptr != NULL
1164 && (sym = *reloc->sym_ptr_ptr) != NULL
1165 && (sym->flags & BSF_KEEP) == 0
1166 && ((sym->flags & BSF_SECTION_SYM) == 0
1167 || (EMIT_SECTION_SYMBOLS
1168 && !bfd_is_abs_section (sym->section))))
1169 as_bad_where (file, line, _("redefined symbol cannot be used on reloc"));
1170
1171 s = bfd_install_relocation (stdoutput, reloc,
1172 fragp->fr_literal, fragp->fr_address,
1173 sec, &err);
1174 switch (s)
1175 {
1176 case bfd_reloc_ok:
1177 break;
1178 case bfd_reloc_overflow:
1179 as_bad_where (file, line, _("relocation overflow"));
1180 break;
1181 case bfd_reloc_outofrange:
1182 as_bad_where (file, line, _("relocation out of range"));
1183 break;
1184 default:
1185 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1186 file, line, s);
1187 }
1188 }
1189
1190 static fragS *
1191 get_frag_for_reloc (fragS *last_frag,
1192 const segment_info_type *seginfo,
1193 const struct reloc_list *r)
1194 {
1195 fragS *f;
1196
1197 for (f = last_frag; f != NULL; f = f->fr_next)
1198 if (f->fr_address <= r->u.b.r.address
1199 && r->u.b.r.address < f->fr_address + f->fr_fix)
1200 return f;
1201
1202 for (f = seginfo->frchainP->frch_root; f != NULL; f = f->fr_next)
1203 if (f->fr_address <= r->u.b.r.address
1204 && r->u.b.r.address < f->fr_address + f->fr_fix)
1205 return f;
1206
1207 for (f = seginfo->frchainP->frch_root; f != NULL; f = f->fr_next)
1208 if (f->fr_address <= r->u.b.r.address
1209 && r->u.b.r.address <= f->fr_address + f->fr_fix)
1210 return f;
1211
1212 as_bad_where (r->file, r->line,
1213 _("reloc not within (fixed part of) section"));
1214 return NULL;
1215 }
1216
1217 static void
1218 write_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec,
1219 void *xxx ATTRIBUTE_UNUSED)
1220 {
1221 segment_info_type *seginfo = seg_info (sec);
1222 unsigned int n;
1223 struct reloc_list *my_reloc_list, **rp, *r;
1224 arelent **relocs;
1225 fixS *fixp;
1226 fragS *last_frag;
1227
1228 /* If seginfo is NULL, we did not create this section; don't do
1229 anything with it. */
1230 if (seginfo == NULL)
1231 return;
1232
1233 n = 0;
1234 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
1235 if (!fixp->fx_done)
1236 n++;
1237
1238 #ifdef RELOC_EXPANSION_POSSIBLE
1239 n *= MAX_RELOC_EXPANSION;
1240 #endif
1241
1242 /* Extract relocs for this section from reloc_list. */
1243 rp = &reloc_list;
1244
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 valueT 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_section_flags (sec);
1350 flags |= SEC_RELOC;
1351 bfd_set_section_flags (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_section_flags (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_section_name (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 (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_rename_section (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_section_flags (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_section_flags (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 (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 /* Create a relocation against an entry in a GNU Build attribute section. */
1890
1891 static void
1892 create_note_reloc (segT sec,
1893 symbolS * sym,
1894 bfd_size_type note_offset,
1895 bfd_size_type desc2_offset,
1896 int reloc_type,
1897 bfd_vma addend,
1898 char * note)
1899 {
1900 struct reloc_list * reloc;
1901
1902 reloc = XNEW (struct reloc_list);
1903
1904 /* We create a .b type reloc as resolve_reloc_expr_symbols() has already been called. */
1905 reloc->u.b.sec = sec;
1906 reloc->u.b.s = symbol_get_bfdsym (sym);
1907 reloc->u.b.r.sym_ptr_ptr = & reloc->u.b.s;
1908 reloc->u.b.r.address = note_offset + desc2_offset;
1909 reloc->u.b.r.addend = addend;
1910 reloc->u.b.r.howto = bfd_reloc_type_lookup (stdoutput, reloc_type);
1911
1912 if (reloc->u.b.r.howto == NULL)
1913 {
1914 as_bad (_("unable to create reloc for build note"));
1915 return;
1916 }
1917
1918 reloc->file = N_("<gnu build note>");
1919 reloc->line = 0;
1920
1921 reloc->next = reloc_list;
1922 reloc_list = reloc;
1923
1924 /* For REL relocs, store the addend in the section. */
1925 if (! sec->use_rela_p
1926 /* The SH target is a special case that uses RELA relocs
1927 but still stores the addend in the word being relocated. */
1928 || strstr (bfd_get_target (stdoutput), "-sh") != NULL)
1929 {
1930 if (target_big_endian)
1931 {
1932 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1933 note[desc2_offset + 3] = addend;
1934 else
1935 note[desc2_offset + 7] = addend;
1936 }
1937 else
1938 note[desc2_offset] = addend;
1939 }
1940 }
1941
1942 static void
1943 maybe_generate_build_notes (void)
1944 {
1945 segT sec;
1946 char * note;
1947 offsetT note_size;
1948 offsetT total_size;
1949 offsetT desc_size;
1950 offsetT desc2_offset;
1951 int desc_reloc;
1952 symbolS * sym;
1953 asymbol * bsym;
1954
1955 if (! flag_generate_build_notes
1956 || bfd_get_section_by_name (stdoutput,
1957 GNU_BUILD_ATTRS_SECTION_NAME) != NULL)
1958 return;
1959
1960 /* Create a GNU Build Attribute section. */
1961 sec = subseg_new (GNU_BUILD_ATTRS_SECTION_NAME, FALSE);
1962 elf_section_type (sec) = SHT_NOTE;
1963 bfd_set_section_flags (sec, (SEC_READONLY | SEC_HAS_CONTENTS | SEC_DATA
1964 | SEC_OCTETS));
1965 bfd_set_section_alignment (sec, 2);
1966
1967 /* Work out the size of the notes that we will create,
1968 and the relocation we should use. */
1969 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1970 {
1971 note_size = 28;
1972 desc_size = 8; /* Two 4-byte offsets. */
1973 desc2_offset = 24;
1974
1975 /* FIXME: The BFD backend for the CRX target does not support the
1976 BFD_RELOC_32, even though it really should. Likewise for the
1977 CR16 target. So we have special case code here... */
1978 if (strstr (bfd_get_target (stdoutput), "-crx") != NULL)
1979 desc_reloc = BFD_RELOC_CRX_NUM32;
1980 else if (strstr (bfd_get_target (stdoutput), "-cr16") != NULL)
1981 desc_reloc = BFD_RELOC_CR16_NUM32;
1982 else
1983 desc_reloc = BFD_RELOC_32;
1984 }
1985 else
1986 {
1987 note_size = 36;
1988 desc_size = 16; /* Two 8-byte offsets. */
1989 desc2_offset = 28;
1990 /* FIXME: The BFD backend for the IA64 target does not support the
1991 BFD_RELOC_64, even though it really should. The HPPA backend
1992 has a similar issue, although it does not support BFD_RELOCs at
1993 all! So we have special case code to handle these targets. */
1994 if (strstr (bfd_get_target (stdoutput), "-ia64") != NULL)
1995 desc_reloc = target_big_endian ? BFD_RELOC_IA64_DIR32MSB : BFD_RELOC_IA64_DIR32LSB;
1996 else if (strstr (bfd_get_target (stdoutput), "-hppa") != NULL)
1997 desc_reloc = 80; /* R_PARISC_DIR64. */
1998 else
1999 desc_reloc = BFD_RELOC_64;
2000 }
2001
2002 /* We have to create a note for *each* code section.
2003 Linker garbage collection might discard some. */
2004 total_size = 0;
2005 note = NULL;
2006
2007 for (sym = symbol_rootP; sym != NULL; sym = symbol_next (sym))
2008 if ((bsym = symbol_get_bfdsym (sym)) != NULL
2009 && bsym->flags & BSF_SECTION_SYM
2010 && bsym->section != NULL
2011 /* Skip linkonce sections - we cannot use these section symbols as they may disappear. */
2012 && (bsym->section->flags & (SEC_CODE | SEC_LINK_ONCE)) == SEC_CODE
2013 /* Not all linkonce sections are flagged... */
2014 && strncmp (S_GET_NAME (sym), ".gnu.linkonce", sizeof ".gnu.linkonce" - 1) != 0)
2015 {
2016 /* Create a version note. */
2017 frag_now_fix ();
2018 note = frag_more (note_size);
2019 memset (note, 0, note_size);
2020
2021 if (target_big_endian)
2022 {
2023 note[3] = 8; /* strlen (name) + 1. */
2024 note[7] = desc_size; /* Two 8-byte offsets. */
2025 note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2026 note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2027 }
2028 else
2029 {
2030 note[0] = 8; /* strlen (name) + 1. */
2031 note[4] = desc_size; /* Two 8-byte offsets. */
2032 note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2033 note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2034 }
2035
2036 /* The a1 version number indicates that this note was
2037 generated by the assembler and not the gcc annobin plugin. */
2038 memcpy (note + 12, "GA$\ 13a1", 8);
2039
2040 /* Create a relocation to install the start address of the note... */
2041 create_note_reloc (sec, sym, total_size, 20, desc_reloc, 0, note);
2042
2043 /* ...and another one to install the end address. */
2044 create_note_reloc (sec, sym, total_size, desc2_offset, desc_reloc,
2045 bfd_section_size (bsym->section),
2046 note);
2047
2048 total_size += note_size;
2049 /* FIXME: Maybe add a note recording the assembler command line and version ? */
2050 }
2051
2052 /* Install the note(s) into the section. */
2053 if (total_size)
2054 bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, total_size);
2055 subsegs_finish_section (sec);
2056 relax_segment (seg_info (sec)->frchainP->frch_root, sec, 0);
2057 size_seg (stdoutput, sec, NULL);
2058 }
2059 #endif /* OBJ_ELF */
2060
2061 /* Write the object file. */
2062
2063 void
2064 write_object_file (void)
2065 {
2066 struct relax_seg_info rsi;
2067 #ifndef WORKING_DOT_WORD
2068 fragS *fragP; /* Track along all frags. */
2069 #endif
2070
2071 subsegs_finish ();
2072
2073 #ifdef md_pre_output_hook
2074 md_pre_output_hook;
2075 #endif
2076
2077 #ifdef md_pre_relax_hook
2078 md_pre_relax_hook;
2079 #endif
2080
2081 /* From now on, we don't care about sub-segments. Build one frag chain
2082 for each segment. Linked through fr_next. */
2083
2084 /* Remove the sections created by gas for its own purposes. */
2085 {
2086 int i;
2087
2088 bfd_section_list_remove (stdoutput, reg_section);
2089 bfd_section_list_remove (stdoutput, expr_section);
2090 stdoutput->section_count -= 2;
2091 i = 0;
2092 bfd_map_over_sections (stdoutput, renumber_sections, &i);
2093 }
2094
2095 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
2096
2097 /* We have two segments. If user gave -R flag, then we must put the
2098 data frags into the text segment. Do this before relaxing so
2099 we know to take advantage of -R and make shorter addresses. */
2100 if (flag_readonly_data_in_text)
2101 {
2102 merge_data_into_text ();
2103 }
2104
2105 rsi.pass = 0;
2106 while (1)
2107 {
2108 #ifndef WORKING_DOT_WORD
2109 /* We need to reset the markers in the broken word list and
2110 associated frags between calls to relax_segment (via
2111 relax_seg). Since the broken word list is global, we do it
2112 once per round, rather than locally in relax_segment for each
2113 segment. */
2114 struct broken_word *brokp;
2115
2116 for (brokp = broken_words;
2117 brokp != (struct broken_word *) NULL;
2118 brokp = brokp->next_broken_word)
2119 {
2120 brokp->added = 0;
2121
2122 if (brokp->dispfrag != (fragS *) NULL
2123 && brokp->dispfrag->fr_type == rs_broken_word)
2124 brokp->dispfrag->fr_subtype = 0;
2125 }
2126 #endif
2127
2128 rsi.changed = 0;
2129 bfd_map_over_sections (stdoutput, relax_seg, &rsi);
2130 rsi.pass++;
2131 if (!rsi.changed)
2132 break;
2133 }
2134
2135 /* Note - Most ports will use the default value of
2136 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
2137 local symbols to be resolved, removing their frag information.
2138 Some ports however, will not have finished relaxing all of
2139 their frags and will still need the local symbol frag
2140 information. These ports can set
2141 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
2142 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
2143
2144 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
2145
2146 /* Relaxation has completed. Freeze all syms. */
2147 finalize_syms = 1;
2148
2149 dwarf2dbg_final_check ();
2150
2151 #ifdef md_post_relax_hook
2152 md_post_relax_hook;
2153 #endif
2154
2155 #ifdef OBJ_ELF
2156 if (IS_ELF)
2157 create_obj_attrs_section ();
2158 #endif
2159
2160 #ifndef WORKING_DOT_WORD
2161 {
2162 struct broken_word *lie;
2163 struct broken_word **prevP;
2164
2165 prevP = &broken_words;
2166 for (lie = broken_words; lie; lie = lie->next_broken_word)
2167 if (!lie->added)
2168 {
2169 expressionS exp;
2170
2171 subseg_change (lie->seg, lie->subseg);
2172 exp.X_op = O_subtract;
2173 exp.X_add_symbol = lie->add;
2174 exp.X_op_symbol = lie->sub;
2175 exp.X_add_number = lie->addnum;
2176 #ifdef TC_CONS_FIX_NEW
2177 TC_CONS_FIX_NEW (lie->frag,
2178 lie->word_goes_here - lie->frag->fr_literal,
2179 2, &exp, TC_PARSE_CONS_RETURN_NONE);
2180 #else
2181 fix_new_exp (lie->frag,
2182 lie->word_goes_here - lie->frag->fr_literal,
2183 2, &exp, 0, BFD_RELOC_16);
2184 #endif
2185 *prevP = lie->next_broken_word;
2186 }
2187 else
2188 prevP = &(lie->next_broken_word);
2189
2190 for (lie = broken_words; lie;)
2191 {
2192 struct broken_word *untruth;
2193 char *table_ptr;
2194 addressT table_addr;
2195 addressT from_addr, to_addr;
2196 int n, m;
2197
2198 subseg_change (lie->seg, lie->subseg);
2199 fragP = lie->dispfrag;
2200
2201 /* Find out how many broken_words go here. */
2202 n = 0;
2203 for (untruth = lie;
2204 untruth && untruth->dispfrag == fragP;
2205 untruth = untruth->next_broken_word)
2206 if (untruth->added == 1)
2207 n++;
2208
2209 table_ptr = lie->dispfrag->fr_opcode;
2210 table_addr = (lie->dispfrag->fr_address
2211 + (table_ptr - lie->dispfrag->fr_literal));
2212 /* Create the jump around the long jumps. This is a short
2213 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
2214 from_addr = table_addr;
2215 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
2216 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
2217 lie->add);
2218 table_ptr += md_short_jump_size;
2219 table_addr += md_short_jump_size;
2220
2221 for (m = 0;
2222 lie && lie->dispfrag == fragP;
2223 m++, lie = lie->next_broken_word)
2224 {
2225 if (lie->added == 2)
2226 continue;
2227 /* Patch the jump table. */
2228 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2229 untruth && untruth->dispfrag == fragP;
2230 untruth = untruth->next_broken_word)
2231 {
2232 if (untruth->use_jump == lie)
2233 {
2234 /* This is the offset from ??? to table_ptr+0.
2235 The target is the same for all users of this
2236 md_long_jump, but the "sub" bases (and hence the
2237 offsets) may be different. */
2238 addressT to_word = table_addr - S_GET_VALUE (untruth->sub);
2239 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
2240 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_word, untruth);
2241 #endif
2242 md_number_to_chars (untruth->word_goes_here, to_word, 2);
2243 }
2244 }
2245
2246 /* Install the long jump. */
2247 /* This is a long jump from table_ptr+0 to the final target. */
2248 from_addr = table_addr;
2249 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
2250 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
2251 lie->add);
2252 table_ptr += md_long_jump_size;
2253 table_addr += md_long_jump_size;
2254 }
2255 }
2256 }
2257 #endif /* not WORKING_DOT_WORD */
2258
2259 /* Resolve symbol values. This needs to be done before processing
2260 the relocations. */
2261 if (symbol_rootP)
2262 {
2263 symbolS *symp;
2264
2265 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
2266 resolve_symbol_value (symp);
2267 }
2268 resolve_local_symbol_values ();
2269 resolve_reloc_expr_symbols ();
2270
2271 #ifdef OBJ_ELF
2272 if (IS_ELF)
2273 maybe_generate_build_notes ();
2274 #endif
2275
2276 PROGRESS (1);
2277
2278 #ifdef tc_frob_file_before_adjust
2279 tc_frob_file_before_adjust ();
2280 #endif
2281 #ifdef obj_frob_file_before_adjust
2282 obj_frob_file_before_adjust ();
2283 #endif
2284
2285 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
2286
2287 #ifdef tc_frob_file_before_fix
2288 tc_frob_file_before_fix ();
2289 #endif
2290 #ifdef obj_frob_file_before_fix
2291 obj_frob_file_before_fix ();
2292 #endif
2293
2294 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
2295
2296 /* Set up symbol table, and write it out. */
2297 if (symbol_rootP)
2298 {
2299 symbolS *symp;
2300 bfd_boolean skip_next_symbol = FALSE;
2301
2302 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
2303 {
2304 int punt = 0;
2305 const char *name;
2306
2307 if (skip_next_symbol)
2308 {
2309 /* Don't do anything besides moving the value of the
2310 symbol from the GAS value-field to the BFD value-field. */
2311 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
2312 skip_next_symbol = FALSE;
2313 continue;
2314 }
2315
2316 if (symbol_mri_common_p (symp))
2317 {
2318 if (S_IS_EXTERNAL (symp))
2319 as_bad (_("%s: global symbols not supported in common sections"),
2320 S_GET_NAME (symp));
2321 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2322 continue;
2323 }
2324
2325 name = S_GET_NAME (symp);
2326 if (name)
2327 {
2328 const char *name2 =
2329 decode_local_label_name ((char *) S_GET_NAME (symp));
2330 /* They only differ if `name' is a fb or dollar local
2331 label name. */
2332 if (name2 != name && ! S_IS_DEFINED (symp))
2333 as_bad (_("local label `%s' is not defined"), name2);
2334 }
2335
2336 /* Do it again, because adjust_reloc_syms might introduce
2337 more symbols. They'll probably only be section symbols,
2338 but they'll still need to have the values computed. */
2339 resolve_symbol_value (symp);
2340
2341 /* Skip symbols which were equated to undefined or common
2342 symbols. */
2343 if (symbol_equated_reloc_p (symp)
2344 || S_IS_WEAKREFR (symp))
2345 {
2346 const char *sname = S_GET_NAME (symp);
2347
2348 if (S_IS_COMMON (symp)
2349 && !TC_FAKE_LABEL (sname)
2350 && !S_IS_WEAKREFR (symp))
2351 {
2352 expressionS *e = symbol_get_value_expression (symp);
2353
2354 as_bad (_("`%s' can't be equated to common symbol `%s'"),
2355 sname, S_GET_NAME (e->X_add_symbol));
2356 }
2357 if (S_GET_SEGMENT (symp) == reg_section)
2358 {
2359 /* Report error only if we know the symbol name. */
2360 if (S_GET_NAME (symp) != reg_section->name)
2361 as_bad (_("can't make global register symbol `%s'"),
2362 sname);
2363 }
2364 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2365 continue;
2366 }
2367
2368 #ifdef obj_frob_symbol
2369 obj_frob_symbol (symp, punt);
2370 #endif
2371 #ifdef tc_frob_symbol
2372 if (! punt || symbol_used_in_reloc_p (symp))
2373 tc_frob_symbol (symp, punt);
2374 #endif
2375
2376 /* If we don't want to keep this symbol, splice it out of
2377 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
2378 want section symbols. Otherwise, we skip local symbols
2379 and symbols that the frob_symbol macros told us to punt,
2380 but we keep such symbols if they are used in relocs. */
2381 if (symp == abs_section_sym
2382 || (! EMIT_SECTION_SYMBOLS
2383 && symbol_section_p (symp))
2384 /* Note that S_IS_EXTERNAL and S_IS_LOCAL are not always
2385 opposites. Sometimes the former checks flags and the
2386 latter examines the name... */
2387 || (!S_IS_EXTERNAL (symp)
2388 && (punt || S_IS_LOCAL (symp) ||
2389 (S_IS_WEAKREFD (symp) && ! symbol_used_p (symp)))
2390 && ! symbol_used_in_reloc_p (symp)))
2391 {
2392 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2393
2394 /* After symbol_remove, symbol_next(symp) still returns
2395 the one that came after it in the chain. So we don't
2396 need to do any extra cleanup work here. */
2397 continue;
2398 }
2399
2400 /* Make sure we really got a value for the symbol. */
2401 if (! symbol_resolved_p (symp))
2402 {
2403 as_bad (_("can't resolve value for symbol `%s'"),
2404 S_GET_NAME (symp));
2405 symbol_mark_resolved (symp);
2406 }
2407
2408 /* Set the value into the BFD symbol. Up til now the value
2409 has only been kept in the gas symbolS struct. */
2410 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
2411
2412 /* A warning construct is a warning symbol followed by the
2413 symbol warned about. Don't let anything object-format or
2414 target-specific muck with it; it's ready for output. */
2415 if (symbol_get_bfdsym (symp)->flags & BSF_WARNING)
2416 skip_next_symbol = TRUE;
2417 }
2418 }
2419
2420 PROGRESS (1);
2421
2422 /* Now do any format-specific adjustments to the symbol table, such
2423 as adding file symbols. */
2424 #ifdef tc_adjust_symtab
2425 tc_adjust_symtab ();
2426 #endif
2427 #ifdef obj_adjust_symtab
2428 obj_adjust_symtab ();
2429 #endif
2430
2431 /* Stop if there is an error. */
2432 if (had_errors ())
2433 return;
2434
2435 /* Now that all the sizes are known, and contents correct, we can
2436 start writing to the file. */
2437 set_symtab ();
2438
2439 /* If *_frob_file changes the symbol value at this point, it is
2440 responsible for moving the changed value into symp->bsym->value
2441 as well. Hopefully all symbol value changing can be done in
2442 *_frob_symbol. */
2443 #ifdef tc_frob_file
2444 tc_frob_file ();
2445 #endif
2446 #ifdef obj_frob_file
2447 obj_frob_file ();
2448 #endif
2449 #ifdef obj_coff_generate_pdata
2450 obj_coff_generate_pdata ();
2451 #endif
2452
2453 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
2454
2455 #ifdef tc_frob_file_after_relocs
2456 tc_frob_file_after_relocs ();
2457 #endif
2458 #ifdef obj_frob_file_after_relocs
2459 obj_frob_file_after_relocs ();
2460 #endif
2461
2462 #if defined OBJ_ELF || defined OBJ_MAYBE_ELF
2463 if (IS_ELF && flag_use_elf_stt_common)
2464 stdoutput->flags |= BFD_CONVERT_ELF_COMMON | BFD_USE_ELF_STT_COMMON;
2465 #endif
2466
2467 /* Once all relocations have been written, we can compress the
2468 contents of the debug sections. This needs to be done before
2469 we start writing any sections, because it will affect the file
2470 layout, which is fixed once we start writing contents. */
2471 if (flag_compress_debug)
2472 {
2473 if (flag_compress_debug == COMPRESS_DEBUG_GABI_ZLIB)
2474 stdoutput->flags |= BFD_COMPRESS | BFD_COMPRESS_GABI;
2475 else
2476 stdoutput->flags |= BFD_COMPRESS;
2477 bfd_map_over_sections (stdoutput, compress_debug, (char *) 0);
2478 }
2479
2480 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
2481 }
2482
2483 #ifdef TC_GENERIC_RELAX_TABLE
2484 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2485
2486 long
2487 relax_frag (segT segment, fragS *fragP, long stretch)
2488 {
2489 const relax_typeS *this_type;
2490 const relax_typeS *start_type;
2491 relax_substateT next_state;
2492 relax_substateT this_state;
2493 offsetT growth;
2494 offsetT aim;
2495 addressT target;
2496 addressT address;
2497 symbolS *symbolP;
2498 const relax_typeS *table;
2499
2500 target = fragP->fr_offset;
2501 address = fragP->fr_address + fragP->fr_fix;
2502 table = TC_GENERIC_RELAX_TABLE;
2503 this_state = fragP->fr_subtype;
2504 start_type = this_type = table + this_state;
2505 symbolP = fragP->fr_symbol;
2506
2507 if (symbolP)
2508 {
2509 fragS *sym_frag;
2510
2511 sym_frag = symbol_get_frag (symbolP);
2512
2513 #ifndef DIFF_EXPR_OK
2514 know (sym_frag != NULL);
2515 #endif
2516 know (S_GET_SEGMENT (symbolP) != absolute_section
2517 || sym_frag == &zero_address_frag);
2518 target += S_GET_VALUE (symbolP);
2519
2520 /* If SYM_FRAG has yet to be reached on this pass, assume it
2521 will move by STRETCH just as we did, unless there is an
2522 alignment frag between here and SYM_FRAG. An alignment may
2523 well absorb any STRETCH, and we don't want to choose a larger
2524 branch insn by overestimating the needed reach of this
2525 branch. It isn't critical to calculate TARGET exactly; We
2526 know we'll be doing another pass if STRETCH is non-zero. */
2527
2528 if (stretch != 0
2529 && sym_frag->relax_marker != fragP->relax_marker
2530 && S_GET_SEGMENT (symbolP) == segment)
2531 {
2532 if (stretch < 0
2533 || sym_frag->region == fragP->region)
2534 target += stretch;
2535 /* If we get here we know we have a forward branch. This
2536 relax pass may have stretched previous instructions so
2537 far that omitting STRETCH would make the branch
2538 negative. Don't allow this in case the negative reach is
2539 large enough to require a larger branch instruction. */
2540 else if (target < address)
2541 return 0;
2542 }
2543 }
2544
2545 aim = target - address;
2546 #ifdef TC_PCREL_ADJUST
2547 /* Currently only the ns32k and arc needs this. */
2548 aim += TC_PCREL_ADJUST (fragP);
2549 #endif
2550
2551 #ifdef md_prepare_relax_scan
2552 /* Formerly called M68K_AIM_KLUDGE. */
2553 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2554 #endif
2555
2556 if (aim < 0)
2557 {
2558 /* Look backwards. */
2559 for (next_state = this_type->rlx_more; next_state;)
2560 if (aim >= this_type->rlx_backward)
2561 next_state = 0;
2562 else
2563 {
2564 /* Grow to next state. */
2565 this_state = next_state;
2566 this_type = table + this_state;
2567 next_state = this_type->rlx_more;
2568 }
2569 }
2570 else
2571 {
2572 /* Look forwards. */
2573 for (next_state = this_type->rlx_more; next_state;)
2574 if (aim <= this_type->rlx_forward)
2575 next_state = 0;
2576 else
2577 {
2578 /* Grow to next state. */
2579 this_state = next_state;
2580 this_type = table + this_state;
2581 next_state = this_type->rlx_more;
2582 }
2583 }
2584
2585 growth = this_type->rlx_length - start_type->rlx_length;
2586 if (growth != 0)
2587 fragP->fr_subtype = this_state;
2588 return growth;
2589 }
2590
2591 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2592
2593 /* Relax_align. Advance location counter to next address that has 'alignment'
2594 lowest order bits all 0s, return size of adjustment made. */
2595 static relax_addressT
2596 relax_align (relax_addressT address, /* Address now. */
2597 int alignment /* Alignment (binary). */)
2598 {
2599 relax_addressT mask;
2600 relax_addressT new_address;
2601
2602 mask = ~((relax_addressT) ~0 << alignment);
2603 new_address = (address + mask) & (~mask);
2604 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2605 if (linkrelax)
2606 /* We must provide lots of padding, so the linker can discard it
2607 when needed. The linker will not add extra space, ever. */
2608 new_address += (1 << alignment);
2609 #endif
2610 return (new_address - address);
2611 }
2612
2613 /* Now we have a segment, not a crowd of sub-segments, we can make
2614 fr_address values.
2615
2616 Relax the frags.
2617
2618 After this, all frags in this segment have addresses that are correct
2619 within the segment. Since segments live in different file addresses,
2620 these frag addresses may not be the same as final object-file
2621 addresses. */
2622
2623 int
2624 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2625 {
2626 unsigned long frag_count;
2627 struct frag *fragP;
2628 relax_addressT address;
2629 int region;
2630 int ret;
2631
2632 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2633 subseg_change (segment, 0);
2634
2635 /* For each frag in segment: count and store (a 1st guess of)
2636 fr_address. */
2637 address = 0;
2638 region = 0;
2639 for (frag_count = 0, fragP = segment_frag_root;
2640 fragP;
2641 fragP = fragP->fr_next, frag_count ++)
2642 {
2643 fragP->region = region;
2644 fragP->relax_marker = 0;
2645 fragP->fr_address = address;
2646 address += fragP->fr_fix;
2647
2648 switch (fragP->fr_type)
2649 {
2650 case rs_fill:
2651 address += fragP->fr_offset * fragP->fr_var;
2652 break;
2653
2654 case rs_align:
2655 case rs_align_code:
2656 case rs_align_test:
2657 {
2658 addressT offset = relax_align (address, (int) fragP->fr_offset);
2659
2660 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2661 offset = 0;
2662
2663 if (offset % fragP->fr_var != 0)
2664 {
2665 as_bad_where (fragP->fr_file, fragP->fr_line,
2666 ngettext ("alignment padding (%lu byte) "
2667 "not a multiple of %ld",
2668 "alignment padding (%lu bytes) "
2669 "not a multiple of %ld",
2670 (unsigned long) offset),
2671 (unsigned long) offset, (long) fragP->fr_var);
2672 offset -= (offset % fragP->fr_var);
2673 }
2674
2675 address += offset;
2676 region += 1;
2677 }
2678 break;
2679
2680 case rs_org:
2681 /* Assume .org is nugatory. It will grow with 1st relax. */
2682 region += 1;
2683 break;
2684
2685 case rs_space:
2686 case rs_space_nop:
2687 break;
2688
2689 case rs_machine_dependent:
2690 /* If fr_symbol is an expression, this call to
2691 resolve_symbol_value sets up the correct segment, which will
2692 likely be needed in md_estimate_size_before_relax. */
2693 if (fragP->fr_symbol)
2694 resolve_symbol_value (fragP->fr_symbol);
2695
2696 address += md_estimate_size_before_relax (fragP, segment);
2697 break;
2698
2699 #ifndef WORKING_DOT_WORD
2700 /* Broken words don't concern us yet. */
2701 case rs_broken_word:
2702 break;
2703 #endif
2704
2705 case rs_leb128:
2706 /* Initial guess is always 1; doing otherwise can result in
2707 stable solutions that are larger than the minimum. */
2708 address += fragP->fr_offset = 1;
2709 break;
2710
2711 case rs_cfa:
2712 address += eh_frame_estimate_size_before_relax (fragP);
2713 break;
2714
2715 case rs_dwarf2dbg:
2716 address += dwarf2dbg_estimate_size_before_relax (fragP);
2717 break;
2718
2719 default:
2720 BAD_CASE (fragP->fr_type);
2721 break;
2722 }
2723 }
2724
2725 /* Do relax(). */
2726 {
2727 unsigned long max_iterations;
2728
2729 /* Cumulative address adjustment. */
2730 offsetT stretch;
2731
2732 /* Have we made any adjustment this pass? We can't just test
2733 stretch because one piece of code may have grown and another
2734 shrank. */
2735 int stretched;
2736
2737 /* Most horrible, but gcc may give us some exception data that
2738 is impossible to assemble, of the form
2739
2740 .align 4
2741 .byte 0, 0
2742 .uleb128 end - start
2743 start:
2744 .space 128*128 - 1
2745 .align 4
2746 end:
2747
2748 If the leb128 is two bytes in size, then end-start is 128*128,
2749 which requires a three byte leb128. If the leb128 is three
2750 bytes in size, then end-start is 128*128-1, which requires a
2751 two byte leb128. We work around this dilemma by inserting
2752 an extra 4 bytes of alignment just after the .align. This
2753 works because the data after the align is accessed relative to
2754 the end label.
2755
2756 This counter is used in a tiny state machine to detect
2757 whether a leb128 followed by an align is impossible to
2758 relax. */
2759 int rs_leb128_fudge = 0;
2760
2761 /* We want to prevent going into an infinite loop where one frag grows
2762 depending upon the location of a symbol which is in turn moved by
2763 the growing frag. eg:
2764
2765 foo = .
2766 .org foo+16
2767 foo = .
2768
2769 So we dictate that this algorithm can be at most O2. */
2770 max_iterations = frag_count * frag_count;
2771 /* Check for overflow. */
2772 if (max_iterations < frag_count)
2773 max_iterations = frag_count;
2774
2775 ret = 0;
2776 do
2777 {
2778 stretch = 0;
2779 stretched = 0;
2780
2781 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2782 {
2783 offsetT growth = 0;
2784 addressT was_address;
2785 offsetT offset;
2786 symbolS *symbolP;
2787
2788 fragP->relax_marker ^= 1;
2789 was_address = fragP->fr_address;
2790 address = fragP->fr_address += stretch;
2791 symbolP = fragP->fr_symbol;
2792 offset = fragP->fr_offset;
2793
2794 switch (fragP->fr_type)
2795 {
2796 case rs_fill: /* .fill never relaxes. */
2797 growth = 0;
2798 break;
2799
2800 #ifndef WORKING_DOT_WORD
2801 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2802 for it I do not want to write it. I do not want to have
2803 anything to do with it. This is not the proper way to
2804 implement this misfeature. */
2805 case rs_broken_word:
2806 {
2807 struct broken_word *lie;
2808 struct broken_word *untruth;
2809
2810 /* Yes this is ugly (storing the broken_word pointer
2811 in the symbol slot). Still, this whole chunk of
2812 code is ugly, and I don't feel like doing anything
2813 about it. Think of it as stubbornness in action. */
2814 growth = 0;
2815 for (lie = (struct broken_word *) (fragP->fr_symbol);
2816 lie && lie->dispfrag == fragP;
2817 lie = lie->next_broken_word)
2818 {
2819
2820 if (lie->added)
2821 continue;
2822
2823 offset = (S_GET_VALUE (lie->add)
2824 + lie->addnum
2825 - S_GET_VALUE (lie->sub));
2826 if (offset <= -32768 || offset >= 32767)
2827 {
2828 if (flag_warn_displacement)
2829 {
2830 char buf[50];
2831 sprint_value (buf, (addressT) lie->addnum);
2832 as_warn_where (fragP->fr_file, fragP->fr_line,
2833 _(".word %s-%s+%s didn't fit"),
2834 S_GET_NAME (lie->add),
2835 S_GET_NAME (lie->sub),
2836 buf);
2837 }
2838 if (fragP->fr_subtype == 0)
2839 {
2840 fragP->fr_subtype++;
2841 growth += md_short_jump_size;
2842 }
2843
2844 /* Redirect *all* words of this table with the same
2845 target, lest we have to handle the case where the
2846 same target but with a offset that fits on this
2847 round overflows at the next relaxation round. */
2848 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2849 untruth && untruth->dispfrag == lie->dispfrag;
2850 untruth = untruth->next_broken_word)
2851 if ((symbol_get_frag (untruth->add)
2852 == symbol_get_frag (lie->add))
2853 && (S_GET_VALUE (untruth->add)
2854 == S_GET_VALUE (lie->add)))
2855 {
2856 untruth->added = 2;
2857 untruth->use_jump = lie;
2858 }
2859
2860 lie->added = 1;
2861 growth += md_long_jump_size;
2862 }
2863 }
2864
2865 break;
2866 } /* case rs_broken_word */
2867 #endif
2868 case rs_align:
2869 case rs_align_code:
2870 case rs_align_test:
2871 {
2872 addressT oldoff, newoff;
2873
2874 oldoff = relax_align (was_address + fragP->fr_fix,
2875 (int) offset);
2876 newoff = relax_align (address + fragP->fr_fix,
2877 (int) offset);
2878
2879 if (fragP->fr_subtype != 0)
2880 {
2881 if (oldoff > fragP->fr_subtype)
2882 oldoff = 0;
2883 if (newoff > fragP->fr_subtype)
2884 newoff = 0;
2885 }
2886
2887 growth = newoff - oldoff;
2888
2889 /* If this align happens to follow a leb128 and
2890 we have determined that the leb128 is bouncing
2891 in size, then break the cycle by inserting an
2892 extra alignment. */
2893 if (growth < 0
2894 && (rs_leb128_fudge & 16) != 0
2895 && (rs_leb128_fudge & 15) >= 2)
2896 {
2897 segment_info_type *seginfo = seg_info (segment);
2898 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2899 struct frag *newf;
2900
2901 newf = frag_alloc (ob);
2902 obstack_blank_fast (ob, fragP->fr_var);
2903 obstack_finish (ob);
2904 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2905 memcpy (newf->fr_literal,
2906 fragP->fr_literal + fragP->fr_fix,
2907 fragP->fr_var);
2908 newf->fr_type = rs_fill;
2909 newf->fr_address = address + fragP->fr_fix + newoff;
2910 newf->fr_fix = 0;
2911 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2912 / fragP->fr_var);
2913 if (newf->fr_offset * newf->fr_var
2914 != (offsetT) 1 << fragP->fr_offset)
2915 {
2916 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2917 newf->fr_var = 1;
2918 }
2919 /* Include size of new frag in GROWTH. */
2920 growth += newf->fr_offset * newf->fr_var;
2921 /* Adjust the new frag address for the amount
2922 we'll add when we process the new frag. */
2923 newf->fr_address -= stretch + growth;
2924 newf->relax_marker ^= 1;
2925 fragP->fr_next = newf;
2926 #ifdef DEBUG
2927 as_warn (_("padding added"));
2928 #endif
2929 }
2930 }
2931 break;
2932
2933 case rs_org:
2934 {
2935 addressT target = offset;
2936 addressT after;
2937
2938 if (symbolP)
2939 {
2940 /* Convert from an actual address to an octet offset
2941 into the section. Here it is assumed that the
2942 section's VMA is zero, and can omit subtracting it
2943 from the symbol's value to get the address offset. */
2944 know (S_GET_SEGMENT (symbolP)->vma == 0);
2945 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2946 }
2947
2948 know (fragP->fr_next);
2949 after = fragP->fr_next->fr_address + stretch;
2950 growth = target - after;
2951
2952 /* Growth may be negative, but variable part of frag
2953 cannot have fewer than 0 chars. That is, we can't
2954 .org backwards. */
2955 if (address + fragP->fr_fix > target)
2956 {
2957 growth = 0;
2958
2959 /* Don't error on first few frag relax passes.
2960 The symbol might be an expression involving
2961 symbol values from other sections. If those
2962 sections have not yet been processed their
2963 frags will all have zero addresses, so we
2964 will calculate incorrect values for them. The
2965 number of passes we allow before giving an
2966 error is somewhat arbitrary. It should be at
2967 least one, with larger values requiring
2968 increasingly contrived dependencies between
2969 frags to trigger a false error. */
2970 if (pass < 2)
2971 {
2972 /* Force another pass. */
2973 ret = 1;
2974 break;
2975 }
2976
2977 as_bad_where (fragP->fr_file, fragP->fr_line,
2978 _("attempt to move .org backwards"));
2979
2980 /* We've issued an error message. Change the
2981 frag to avoid cascading errors. */
2982 fragP->fr_type = rs_align;
2983 fragP->fr_subtype = 0;
2984 fragP->fr_offset = 0;
2985 fragP->fr_fix = after - address;
2986 }
2987 }
2988 break;
2989
2990 case rs_space:
2991 case rs_space_nop:
2992 growth = 0;
2993 if (symbolP)
2994 {
2995 offsetT amount;
2996
2997 amount = S_GET_VALUE (symbolP);
2998 if (S_GET_SEGMENT (symbolP) != absolute_section
2999 || S_IS_COMMON (symbolP)
3000 || ! S_IS_DEFINED (symbolP))
3001 {
3002 as_bad_where (fragP->fr_file, fragP->fr_line,
3003 _(".space specifies non-absolute value"));
3004 /* Prevent repeat of this error message. */
3005 fragP->fr_symbol = 0;
3006 }
3007 else if (amount < 0)
3008 {
3009 /* Don't error on first few frag relax passes.
3010 See rs_org comment for a longer explanation. */
3011 if (pass < 2)
3012 {
3013 ret = 1;
3014 break;
3015 }
3016
3017 as_warn_where (fragP->fr_file, fragP->fr_line,
3018 _(".space, .nops or .fill with negative value, ignored"));
3019 fragP->fr_symbol = 0;
3020 }
3021 else
3022 growth = (was_address + fragP->fr_fix + amount
3023 - fragP->fr_next->fr_address);
3024 }
3025 break;
3026
3027 case rs_machine_dependent:
3028 #ifdef md_relax_frag
3029 growth = md_relax_frag (segment, fragP, stretch);
3030 #else
3031 #ifdef TC_GENERIC_RELAX_TABLE
3032 /* The default way to relax a frag is to look through
3033 TC_GENERIC_RELAX_TABLE. */
3034 growth = relax_frag (segment, fragP, stretch);
3035 #endif /* TC_GENERIC_RELAX_TABLE */
3036 #endif
3037 break;
3038
3039 case rs_leb128:
3040 {
3041 valueT value;
3042 offsetT size;
3043
3044 value = resolve_symbol_value (fragP->fr_symbol);
3045 size = sizeof_leb128 (value, fragP->fr_subtype);
3046 growth = size - fragP->fr_offset;
3047 fragP->fr_offset = size;
3048 }
3049 break;
3050
3051 case rs_cfa:
3052 growth = eh_frame_relax_frag (fragP);
3053 break;
3054
3055 case rs_dwarf2dbg:
3056 growth = dwarf2dbg_relax_frag (fragP);
3057 break;
3058
3059 default:
3060 BAD_CASE (fragP->fr_type);
3061 break;
3062 }
3063 if (growth)
3064 {
3065 stretch += growth;
3066 stretched = 1;
3067 if (fragP->fr_type == rs_leb128)
3068 rs_leb128_fudge += 16;
3069 else if (fragP->fr_type == rs_align
3070 && (rs_leb128_fudge & 16) != 0
3071 && stretch == 0)
3072 rs_leb128_fudge += 16;
3073 else
3074 rs_leb128_fudge = 0;
3075 }
3076 }
3077
3078 if (stretch == 0
3079 && (rs_leb128_fudge & 16) == 0
3080 && (rs_leb128_fudge & -16) != 0)
3081 rs_leb128_fudge += 1;
3082 else
3083 rs_leb128_fudge = 0;
3084 }
3085 /* Until nothing further to relax. */
3086 while (stretched && -- max_iterations);
3087
3088 if (stretched)
3089 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
3090 segment_name (segment));
3091 }
3092
3093 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
3094 if (fragP->last_fr_address != fragP->fr_address)
3095 {
3096 fragP->last_fr_address = fragP->fr_address;
3097 ret = 1;
3098 }
3099 return ret;
3100 }
3101
3102 void
3103 number_to_chars_bigendian (char *buf, valueT val, int n)
3104 {
3105 if (n <= 0)
3106 abort ();
3107 while (n--)
3108 {
3109 buf[n] = val & 0xff;
3110 val >>= 8;
3111 }
3112 }
3113
3114 void
3115 number_to_chars_littleendian (char *buf, valueT val, int n)
3116 {
3117 if (n <= 0)
3118 abort ();
3119 while (n--)
3120 {
3121 *buf++ = val & 0xff;
3122 val >>= 8;
3123 }
3124 }
3125
3126 void
3127 write_print_statistics (FILE *file)
3128 {
3129 fprintf (file, "fixups: %d\n", n_fixups);
3130 }
3131
3132 /* For debugging. */
3133 extern int indent_level;
3134
3135 void
3136 print_fixup (fixS *fixp)
3137 {
3138 indent_level = 1;
3139 fprintf (stderr, "fix ");
3140 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
3141 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
3142 if (fixp->fx_pcrel)
3143 fprintf (stderr, " pcrel");
3144 if (fixp->fx_pcrel_adjust)
3145 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
3146 if (fixp->fx_tcbit)
3147 fprintf (stderr, " tcbit");
3148 if (fixp->fx_done)
3149 fprintf (stderr, " done");
3150 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
3151 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
3152 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
3153 (long) fixp->fx_where,
3154 (unsigned long) fixp->fx_offset,
3155 (unsigned long) fixp->fx_addnumber);
3156 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
3157 fixp->fx_r_type);
3158 if (fixp->fx_addsy)
3159 {
3160 fprintf (stderr, "\n +<");
3161 print_symbol_value_1 (stderr, fixp->fx_addsy);
3162 fprintf (stderr, ">");
3163 }
3164 if (fixp->fx_subsy)
3165 {
3166 fprintf (stderr, "\n -<");
3167 print_symbol_value_1 (stderr, fixp->fx_subsy);
3168 fprintf (stderr, ">");
3169 }
3170 fprintf (stderr, "\n");
3171 #ifdef TC_FIX_DATA_PRINT
3172 TC_FIX_DATA_PRINT (stderr, fixp);
3173 #endif
3174 }
This page took 0.091095 seconds and 3 git commands to generate.