gdb: add target_ops::supports_displaced_step
[deliverable/binutils-gdb.git] / gas / write.c
1 /* write.c - emit .o file
2 Copyright (C) 1986-2020 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 bfd_section_name (sec), bfd_get_filename (stdoutput),
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),
1653 (long) count,
1654 bfd_section_name (sec),
1655 bfd_get_filename (stdoutput),
1656 bfd_errmsg (bfd_get_error ()));
1657 offset += count;
1658 free (buf);
1659 }
1660 continue;
1661 }
1662
1663 gas_assert (count >= 0);
1664 if (fill_size && count)
1665 {
1666 char buf[256];
1667 if (fill_size > sizeof (buf))
1668 {
1669 /* Do it the old way. Can this ever happen? */
1670 while (count--)
1671 {
1672 x = bfd_set_section_contents (stdoutput, sec,
1673 fill_literal,
1674 (file_ptr) offset,
1675 (bfd_size_type) fill_size);
1676 if (!x)
1677 as_fatal (ngettext ("can't fill %ld byte "
1678 "in section %s of %s: '%s'",
1679 "can't fill %ld bytes "
1680 "in section %s of %s: '%s'",
1681 (long) fill_size),
1682 (long) fill_size,
1683 bfd_section_name (sec),
1684 bfd_get_filename (stdoutput),
1685 bfd_errmsg (bfd_get_error ()));
1686 offset += fill_size;
1687 }
1688 }
1689 else
1690 {
1691 /* Build a buffer full of fill objects and output it as
1692 often as necessary. This saves on the overhead of
1693 potentially lots of bfd_set_section_contents calls. */
1694 int n_per_buf, i;
1695 if (fill_size == 1)
1696 {
1697 n_per_buf = sizeof (buf);
1698 memset (buf, *fill_literal, n_per_buf);
1699 }
1700 else
1701 {
1702 char *bufp;
1703 n_per_buf = sizeof (buf) / fill_size;
1704 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1705 memcpy (bufp, fill_literal, fill_size);
1706 }
1707 for (; count > 0; count -= n_per_buf)
1708 {
1709 n_per_buf = n_per_buf > count ? count : n_per_buf;
1710 x = bfd_set_section_contents
1711 (stdoutput, sec, buf, (file_ptr) offset,
1712 (bfd_size_type) n_per_buf * fill_size);
1713 if (!x)
1714 as_fatal (ngettext ("can't fill %ld byte "
1715 "in section %s of %s: '%s'",
1716 "can't fill %ld bytes "
1717 "in section %s of %s: '%s'",
1718 (long) (n_per_buf * fill_size)),
1719 (long) (n_per_buf * fill_size),
1720 bfd_section_name (sec),
1721 bfd_get_filename (stdoutput),
1722 bfd_errmsg (bfd_get_error ()));
1723 offset += n_per_buf * fill_size;
1724 }
1725 }
1726 }
1727 }
1728 }
1729
1730 static void
1731 merge_data_into_text (void)
1732 {
1733 seg_info (text_section)->frchainP->frch_last->fr_next =
1734 seg_info (data_section)->frchainP->frch_root;
1735 seg_info (text_section)->frchainP->frch_last =
1736 seg_info (data_section)->frchainP->frch_last;
1737 seg_info (data_section)->frchainP = 0;
1738 }
1739
1740 static void
1741 set_symtab (void)
1742 {
1743 int nsyms;
1744 asymbol **asympp;
1745 symbolS *symp;
1746 bfd_boolean result;
1747
1748 /* Count symbols. We can't rely on a count made by the loop in
1749 write_object_file, because *_frob_file may add a new symbol or
1750 two. */
1751 nsyms = 0;
1752 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1753 nsyms++;
1754
1755 if (nsyms)
1756 {
1757 int i;
1758 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1759
1760 asympp = (asymbol **) bfd_alloc (stdoutput, amt);
1761 symp = symbol_rootP;
1762 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1763 {
1764 asympp[i] = symbol_get_bfdsym (symp);
1765 if (asympp[i]->flags != BSF_SECTION_SYM
1766 || !(bfd_is_const_section (asympp[i]->section)
1767 && asympp[i]->section->symbol == asympp[i]))
1768 asympp[i]->flags |= BSF_KEEP;
1769 symbol_mark_written (symp);
1770 }
1771 }
1772 else
1773 asympp = 0;
1774 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1775 gas_assert (result);
1776 symbol_table_frozen = 1;
1777 }
1778
1779 /* Finish the subsegments. After every sub-segment, we fake an
1780 ".align ...". This conforms to BSD4.2 brain-damage. We then fake
1781 ".fill 0" because that is the kind of frag that requires least
1782 thought. ".align" frags like to have a following frag since that
1783 makes calculating their intended length trivial. */
1784
1785 #ifndef SUB_SEGMENT_ALIGN
1786 #ifdef HANDLE_ALIGN
1787 /* The last subsegment gets an alignment corresponding to the alignment
1788 of the section. This allows proper nop-filling at the end of
1789 code-bearing sections. */
1790 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1791 (!(FRCHAIN)->frch_next && subseg_text_p (SEG) \
1792 && !do_not_pad_sections_to_alignment \
1793 ? get_recorded_alignment (SEG) \
1794 : 0)
1795 #else
1796 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1797 #endif
1798 #endif
1799
1800 static void
1801 subsegs_finish_section (asection *s)
1802 {
1803 struct frchain *frchainP;
1804 segment_info_type *seginfo = seg_info (s);
1805 if (!seginfo)
1806 return;
1807
1808 for (frchainP = seginfo->frchainP;
1809 frchainP != NULL;
1810 frchainP = frchainP->frch_next)
1811 {
1812 int alignment;
1813
1814 subseg_set (s, frchainP->frch_subseg);
1815
1816 /* This now gets called even if we had errors. In that case,
1817 any alignment is meaningless, and, moreover, will look weird
1818 if we are generating a listing. */
1819 if (had_errors ())
1820 do_not_pad_sections_to_alignment = 1;
1821
1822 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1823 if ((bfd_section_flags (now_seg) & SEC_MERGE)
1824 && now_seg->entsize)
1825 {
1826 unsigned int entsize = now_seg->entsize;
1827 int entalign = 0;
1828
1829 while ((entsize & 1) == 0)
1830 {
1831 ++entalign;
1832 entsize >>= 1;
1833 }
1834
1835 if (entalign > alignment)
1836 alignment = entalign;
1837 }
1838
1839 if (subseg_text_p (now_seg))
1840 frag_align_code (alignment, 0);
1841 else
1842 frag_align (alignment, 0, 0);
1843
1844 /* frag_align will have left a new frag.
1845 Use this last frag for an empty ".fill".
1846
1847 For this segment ...
1848 Create a last frag. Do not leave a "being filled in frag". */
1849 frag_wane (frag_now);
1850 frag_now->fr_fix = 0;
1851 know (frag_now->fr_next == NULL);
1852 }
1853 }
1854
1855 static void
1856 subsegs_finish (void)
1857 {
1858 asection *s;
1859
1860 for (s = stdoutput->sections; s; s = s->next)
1861 subsegs_finish_section (s);
1862 }
1863
1864 #ifdef OBJ_ELF
1865 static void
1866 create_obj_attrs_section (void)
1867 {
1868 segT s;
1869 char *p;
1870 offsetT size;
1871 const char *name;
1872
1873 size = bfd_elf_obj_attr_size (stdoutput);
1874 if (size == 0)
1875 return;
1876
1877 name = get_elf_backend_data (stdoutput)->obj_attrs_section;
1878 if (!name)
1879 name = ".gnu.attributes";
1880 s = subseg_new (name, 0);
1881 elf_section_type (s)
1882 = get_elf_backend_data (stdoutput)->obj_attrs_section_type;
1883 bfd_set_section_flags (s, SEC_READONLY | SEC_DATA);
1884 frag_now_fix ();
1885 p = frag_more (size);
1886 bfd_elf_set_obj_attr_contents (stdoutput, (bfd_byte *)p, size);
1887
1888 subsegs_finish_section (s);
1889 relax_segment (seg_info (s)->frchainP->frch_root, s, 0);
1890 size_seg (stdoutput, s, NULL);
1891 }
1892
1893 /* Create a relocation against an entry in a GNU Build attribute section. */
1894
1895 static void
1896 create_note_reloc (segT sec,
1897 symbolS * sym,
1898 bfd_size_type note_offset,
1899 bfd_size_type desc2_offset,
1900 int reloc_type,
1901 bfd_vma addend,
1902 char * note)
1903 {
1904 struct reloc_list * reloc;
1905
1906 reloc = XNEW (struct reloc_list);
1907
1908 /* We create a .b type reloc as resolve_reloc_expr_symbols() has already been called. */
1909 reloc->u.b.sec = sec;
1910 reloc->u.b.s = symbol_get_bfdsym (sym);
1911 reloc->u.b.r.sym_ptr_ptr = & reloc->u.b.s;
1912 reloc->u.b.r.address = note_offset + desc2_offset;
1913 reloc->u.b.r.addend = addend;
1914 reloc->u.b.r.howto = bfd_reloc_type_lookup (stdoutput, reloc_type);
1915
1916 if (reloc->u.b.r.howto == NULL)
1917 {
1918 as_bad (_("unable to create reloc for build note"));
1919 return;
1920 }
1921
1922 reloc->file = N_("<gnu build note>");
1923 reloc->line = 0;
1924
1925 reloc->next = reloc_list;
1926 reloc_list = reloc;
1927
1928 /* For REL relocs, store the addend in the section. */
1929 if (! sec->use_rela_p
1930 /* The SH target is a special case that uses RELA relocs
1931 but still stores the addend in the word being relocated. */
1932 || strstr (bfd_get_target (stdoutput), "-sh") != NULL)
1933 {
1934 if (target_big_endian)
1935 {
1936 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1937 note[desc2_offset + 3] = addend;
1938 else
1939 note[desc2_offset + 7] = addend;
1940 }
1941 else
1942 note[desc2_offset] = addend;
1943 }
1944 }
1945
1946 static void
1947 maybe_generate_build_notes (void)
1948 {
1949 segT sec;
1950 char * note;
1951 offsetT note_size;
1952 offsetT total_size;
1953 offsetT desc_size;
1954 offsetT desc2_offset;
1955 int desc_reloc;
1956 symbolS * sym;
1957 asymbol * bsym;
1958
1959 if (! flag_generate_build_notes
1960 || bfd_get_section_by_name (stdoutput,
1961 GNU_BUILD_ATTRS_SECTION_NAME) != NULL)
1962 return;
1963
1964 /* Create a GNU Build Attribute section. */
1965 sec = subseg_new (GNU_BUILD_ATTRS_SECTION_NAME, FALSE);
1966 elf_section_type (sec) = SHT_NOTE;
1967 bfd_set_section_flags (sec, (SEC_READONLY | SEC_HAS_CONTENTS | SEC_DATA
1968 | SEC_OCTETS));
1969 bfd_set_section_alignment (sec, 2);
1970
1971 /* Work out the size of the notes that we will create,
1972 and the relocation we should use. */
1973 if (bfd_arch_bits_per_address (stdoutput) <= 32)
1974 {
1975 note_size = 28;
1976 desc_size = 8; /* Two 4-byte offsets. */
1977 desc2_offset = 24;
1978
1979 /* FIXME: The BFD backend for the CRX target does not support the
1980 BFD_RELOC_32, even though it really should. Likewise for the
1981 CR16 target. So we have special case code here... */
1982 if (strstr (bfd_get_target (stdoutput), "-crx") != NULL)
1983 desc_reloc = BFD_RELOC_CRX_NUM32;
1984 else if (strstr (bfd_get_target (stdoutput), "-cr16") != NULL)
1985 desc_reloc = BFD_RELOC_CR16_NUM32;
1986 else
1987 desc_reloc = BFD_RELOC_32;
1988 }
1989 else
1990 {
1991 note_size = 36;
1992 desc_size = 16; /* Two 8-byte offsets. */
1993 desc2_offset = 28;
1994 /* FIXME: The BFD backend for the IA64 target does not support the
1995 BFD_RELOC_64, even though it really should. The HPPA backend
1996 has a similar issue, although it does not support BFD_RELOCs at
1997 all! So we have special case code to handle these targets. */
1998 if (strstr (bfd_get_target (stdoutput), "-ia64") != NULL)
1999 desc_reloc = target_big_endian ? BFD_RELOC_IA64_DIR32MSB : BFD_RELOC_IA64_DIR32LSB;
2000 else if (strstr (bfd_get_target (stdoutput), "-hppa") != NULL)
2001 desc_reloc = 80; /* R_PARISC_DIR64. */
2002 else
2003 desc_reloc = BFD_RELOC_64;
2004 }
2005
2006 /* We have to create a note for *each* code section.
2007 Linker garbage collection might discard some. */
2008 total_size = 0;
2009 note = NULL;
2010
2011 for (sym = symbol_rootP; sym != NULL; sym = symbol_next (sym))
2012 if ((bsym = symbol_get_bfdsym (sym)) != NULL
2013 && bsym->flags & BSF_SECTION_SYM
2014 && bsym->section != NULL
2015 /* Skip linkonce sections - we cannot use these section symbols as they may disappear. */
2016 && (bsym->section->flags & (SEC_CODE | SEC_LINK_ONCE)) == SEC_CODE
2017 /* Not all linkonce sections are flagged... */
2018 && strncmp (S_GET_NAME (sym), ".gnu.linkonce", sizeof ".gnu.linkonce" - 1) != 0)
2019 {
2020 /* Create a version note. */
2021 frag_now_fix ();
2022 note = frag_more (note_size);
2023 memset (note, 0, note_size);
2024
2025 if (target_big_endian)
2026 {
2027 note[3] = 8; /* strlen (name) + 1. */
2028 note[7] = desc_size; /* Two 8-byte offsets. */
2029 note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2030 note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2031 }
2032 else
2033 {
2034 note[0] = 8; /* strlen (name) + 1. */
2035 note[4] = desc_size; /* Two 8-byte offsets. */
2036 note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
2037 note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
2038 }
2039
2040 /* The a1 version number indicates that this note was
2041 generated by the assembler and not the gcc annobin plugin. */
2042 memcpy (note + 12, "GA$\ 13a1", 8);
2043
2044 /* Create a relocation to install the start address of the note... */
2045 create_note_reloc (sec, sym, total_size, 20, desc_reloc, 0, note);
2046
2047 /* ...and another one to install the end address. */
2048 create_note_reloc (sec, sym, total_size, desc2_offset, desc_reloc,
2049 bfd_section_size (bsym->section),
2050 note);
2051
2052 total_size += note_size;
2053 /* FIXME: Maybe add a note recording the assembler command line and version ? */
2054 }
2055
2056 /* Install the note(s) into the section. */
2057 if (total_size)
2058 bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, total_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 (!flag_always_generate_output && 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 #ifndef md_generic_table_relax_frag
2489 #define md_generic_table_relax_frag relax_frag
2490 #endif
2491
2492 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2493
2494 long
2495 relax_frag (segT segment, fragS *fragP, long stretch)
2496 {
2497 const relax_typeS *this_type;
2498 const relax_typeS *start_type;
2499 relax_substateT next_state;
2500 relax_substateT this_state;
2501 offsetT growth;
2502 offsetT aim;
2503 addressT target;
2504 addressT address;
2505 symbolS *symbolP;
2506 const relax_typeS *table;
2507
2508 target = fragP->fr_offset;
2509 address = fragP->fr_address + fragP->fr_fix;
2510 table = TC_GENERIC_RELAX_TABLE;
2511 this_state = fragP->fr_subtype;
2512 start_type = this_type = table + this_state;
2513 symbolP = fragP->fr_symbol;
2514
2515 if (symbolP)
2516 {
2517 fragS *sym_frag;
2518
2519 sym_frag = symbol_get_frag (symbolP);
2520
2521 #ifndef DIFF_EXPR_OK
2522 know (sym_frag != NULL);
2523 #endif
2524 know (S_GET_SEGMENT (symbolP) != absolute_section
2525 || sym_frag == &zero_address_frag);
2526 target += S_GET_VALUE (symbolP);
2527
2528 /* If SYM_FRAG has yet to be reached on this pass, assume it
2529 will move by STRETCH just as we did, unless there is an
2530 alignment frag between here and SYM_FRAG. An alignment may
2531 well absorb any STRETCH, and we don't want to choose a larger
2532 branch insn by overestimating the needed reach of this
2533 branch. It isn't critical to calculate TARGET exactly; We
2534 know we'll be doing another pass if STRETCH is non-zero. */
2535
2536 if (stretch != 0
2537 && sym_frag->relax_marker != fragP->relax_marker
2538 && S_GET_SEGMENT (symbolP) == segment)
2539 {
2540 if (stretch < 0
2541 || sym_frag->region == fragP->region)
2542 target += stretch;
2543 /* If we get here we know we have a forward branch. This
2544 relax pass may have stretched previous instructions so
2545 far that omitting STRETCH would make the branch
2546 negative. Don't allow this in case the negative reach is
2547 large enough to require a larger branch instruction. */
2548 else if (target < address)
2549 return 0;
2550 }
2551 }
2552
2553 aim = target - address;
2554 #ifdef TC_PCREL_ADJUST
2555 /* Currently only the ns32k and arc needs this. */
2556 aim += TC_PCREL_ADJUST (fragP);
2557 #endif
2558
2559 #ifdef md_prepare_relax_scan
2560 /* Formerly called M68K_AIM_KLUDGE. */
2561 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2562 #endif
2563
2564 if (aim < 0)
2565 {
2566 /* Look backwards. */
2567 for (next_state = this_type->rlx_more; next_state;)
2568 if (aim >= this_type->rlx_backward)
2569 next_state = 0;
2570 else
2571 {
2572 /* Grow to next state. */
2573 this_state = next_state;
2574 this_type = table + this_state;
2575 next_state = this_type->rlx_more;
2576 }
2577 }
2578 else
2579 {
2580 /* Look forwards. */
2581 for (next_state = this_type->rlx_more; next_state;)
2582 if (aim <= this_type->rlx_forward)
2583 next_state = 0;
2584 else
2585 {
2586 /* Grow to next state. */
2587 this_state = next_state;
2588 this_type = table + this_state;
2589 next_state = this_type->rlx_more;
2590 }
2591 }
2592
2593 growth = this_type->rlx_length - start_type->rlx_length;
2594 if (growth != 0)
2595 fragP->fr_subtype = this_state;
2596 return growth;
2597 }
2598
2599 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2600
2601 /* Relax_align. Advance location counter to next address that has 'alignment'
2602 lowest order bits all 0s, return size of adjustment made. */
2603 static relax_addressT
2604 relax_align (relax_addressT address, /* Address now. */
2605 int alignment /* Alignment (binary). */)
2606 {
2607 relax_addressT mask;
2608 relax_addressT new_address;
2609
2610 mask = ~((relax_addressT) ~0 << alignment);
2611 new_address = (address + mask) & (~mask);
2612 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2613 if (linkrelax)
2614 /* We must provide lots of padding, so the linker can discard it
2615 when needed. The linker will not add extra space, ever. */
2616 new_address += (1 << alignment);
2617 #endif
2618 return (new_address - address);
2619 }
2620
2621 /* Now we have a segment, not a crowd of sub-segments, we can make
2622 fr_address values.
2623
2624 Relax the frags.
2625
2626 After this, all frags in this segment have addresses that are correct
2627 within the segment. Since segments live in different file addresses,
2628 these frag addresses may not be the same as final object-file
2629 addresses. */
2630
2631 int
2632 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2633 {
2634 unsigned long frag_count;
2635 struct frag *fragP;
2636 relax_addressT address;
2637 int region;
2638 int ret;
2639
2640 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2641 subseg_change (segment, 0);
2642
2643 /* For each frag in segment: count and store (a 1st guess of)
2644 fr_address. */
2645 address = 0;
2646 region = 0;
2647 for (frag_count = 0, fragP = segment_frag_root;
2648 fragP;
2649 fragP = fragP->fr_next, frag_count ++)
2650 {
2651 fragP->region = region;
2652 fragP->relax_marker = 0;
2653 fragP->fr_address = address;
2654 address += fragP->fr_fix;
2655
2656 switch (fragP->fr_type)
2657 {
2658 case rs_fill:
2659 address += fragP->fr_offset * fragP->fr_var;
2660 break;
2661
2662 case rs_align:
2663 case rs_align_code:
2664 case rs_align_test:
2665 {
2666 addressT offset = relax_align (address, (int) fragP->fr_offset);
2667
2668 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2669 offset = 0;
2670
2671 if (offset % fragP->fr_var != 0)
2672 {
2673 as_bad_where (fragP->fr_file, fragP->fr_line,
2674 ngettext ("alignment padding (%lu byte) "
2675 "not a multiple of %ld",
2676 "alignment padding (%lu bytes) "
2677 "not a multiple of %ld",
2678 (unsigned long) offset),
2679 (unsigned long) offset, (long) fragP->fr_var);
2680 offset -= (offset % fragP->fr_var);
2681 }
2682
2683 address += offset;
2684 region += 1;
2685 }
2686 break;
2687
2688 case rs_org:
2689 /* Assume .org is nugatory. It will grow with 1st relax. */
2690 region += 1;
2691 break;
2692
2693 case rs_space:
2694 case rs_space_nop:
2695 break;
2696
2697 case rs_machine_dependent:
2698 /* If fr_symbol is an expression, this call to
2699 resolve_symbol_value sets up the correct segment, which will
2700 likely be needed in md_estimate_size_before_relax. */
2701 if (fragP->fr_symbol)
2702 resolve_symbol_value (fragP->fr_symbol);
2703
2704 address += md_estimate_size_before_relax (fragP, segment);
2705 break;
2706
2707 #ifndef WORKING_DOT_WORD
2708 /* Broken words don't concern us yet. */
2709 case rs_broken_word:
2710 break;
2711 #endif
2712
2713 case rs_leb128:
2714 /* Initial guess is always 1; doing otherwise can result in
2715 stable solutions that are larger than the minimum. */
2716 address += fragP->fr_offset = 1;
2717 break;
2718
2719 case rs_cfa:
2720 address += eh_frame_estimate_size_before_relax (fragP);
2721 break;
2722
2723 case rs_dwarf2dbg:
2724 address += dwarf2dbg_estimate_size_before_relax (fragP);
2725 break;
2726
2727 default:
2728 BAD_CASE (fragP->fr_type);
2729 break;
2730 }
2731 }
2732
2733 /* Do relax(). */
2734 {
2735 unsigned long max_iterations;
2736
2737 /* Cumulative address adjustment. */
2738 offsetT stretch;
2739
2740 /* Have we made any adjustment this pass? We can't just test
2741 stretch because one piece of code may have grown and another
2742 shrank. */
2743 int stretched;
2744
2745 /* Most horrible, but gcc may give us some exception data that
2746 is impossible to assemble, of the form
2747
2748 .align 4
2749 .byte 0, 0
2750 .uleb128 end - start
2751 start:
2752 .space 128*128 - 1
2753 .align 4
2754 end:
2755
2756 If the leb128 is two bytes in size, then end-start is 128*128,
2757 which requires a three byte leb128. If the leb128 is three
2758 bytes in size, then end-start is 128*128-1, which requires a
2759 two byte leb128. We work around this dilemma by inserting
2760 an extra 4 bytes of alignment just after the .align. This
2761 works because the data after the align is accessed relative to
2762 the end label.
2763
2764 This counter is used in a tiny state machine to detect
2765 whether a leb128 followed by an align is impossible to
2766 relax. */
2767 int rs_leb128_fudge = 0;
2768
2769 /* We want to prevent going into an infinite loop where one frag grows
2770 depending upon the location of a symbol which is in turn moved by
2771 the growing frag. eg:
2772
2773 foo = .
2774 .org foo+16
2775 foo = .
2776
2777 So we dictate that this algorithm can be at most O2. */
2778 max_iterations = frag_count * frag_count;
2779 /* Check for overflow. */
2780 if (max_iterations < frag_count)
2781 max_iterations = frag_count;
2782
2783 ret = 0;
2784 do
2785 {
2786 stretch = 0;
2787 stretched = 0;
2788
2789 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2790 {
2791 offsetT growth = 0;
2792 addressT was_address;
2793 offsetT offset;
2794 symbolS *symbolP;
2795
2796 fragP->relax_marker ^= 1;
2797 was_address = fragP->fr_address;
2798 address = fragP->fr_address += stretch;
2799 symbolP = fragP->fr_symbol;
2800 offset = fragP->fr_offset;
2801
2802 switch (fragP->fr_type)
2803 {
2804 case rs_fill: /* .fill never relaxes. */
2805 growth = 0;
2806 break;
2807
2808 #ifndef WORKING_DOT_WORD
2809 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2810 for it I do not want to write it. I do not want to have
2811 anything to do with it. This is not the proper way to
2812 implement this misfeature. */
2813 case rs_broken_word:
2814 {
2815 struct broken_word *lie;
2816 struct broken_word *untruth;
2817
2818 /* Yes this is ugly (storing the broken_word pointer
2819 in the symbol slot). Still, this whole chunk of
2820 code is ugly, and I don't feel like doing anything
2821 about it. Think of it as stubbornness in action. */
2822 growth = 0;
2823 for (lie = (struct broken_word *) (fragP->fr_symbol);
2824 lie && lie->dispfrag == fragP;
2825 lie = lie->next_broken_word)
2826 {
2827
2828 if (lie->added)
2829 continue;
2830
2831 offset = (S_GET_VALUE (lie->add)
2832 + lie->addnum
2833 - S_GET_VALUE (lie->sub));
2834 if (offset <= -32768 || offset >= 32767)
2835 {
2836 if (flag_warn_displacement)
2837 {
2838 char buf[50];
2839 sprint_value (buf, (addressT) lie->addnum);
2840 as_warn_where (fragP->fr_file, fragP->fr_line,
2841 _(".word %s-%s+%s didn't fit"),
2842 S_GET_NAME (lie->add),
2843 S_GET_NAME (lie->sub),
2844 buf);
2845 }
2846 if (fragP->fr_subtype == 0)
2847 {
2848 fragP->fr_subtype++;
2849 growth += md_short_jump_size;
2850 }
2851
2852 /* Redirect *all* words of this table with the same
2853 target, lest we have to handle the case where the
2854 same target but with a offset that fits on this
2855 round overflows at the next relaxation round. */
2856 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2857 untruth && untruth->dispfrag == lie->dispfrag;
2858 untruth = untruth->next_broken_word)
2859 if ((symbol_get_frag (untruth->add)
2860 == symbol_get_frag (lie->add))
2861 && (S_GET_VALUE (untruth->add)
2862 == S_GET_VALUE (lie->add)))
2863 {
2864 untruth->added = 2;
2865 untruth->use_jump = lie;
2866 }
2867
2868 lie->added = 1;
2869 growth += md_long_jump_size;
2870 }
2871 }
2872
2873 break;
2874 } /* case rs_broken_word */
2875 #endif
2876 case rs_align:
2877 case rs_align_code:
2878 case rs_align_test:
2879 {
2880 addressT oldoff, newoff;
2881
2882 oldoff = relax_align (was_address + fragP->fr_fix,
2883 (int) offset);
2884 newoff = relax_align (address + fragP->fr_fix,
2885 (int) offset);
2886
2887 if (fragP->fr_subtype != 0)
2888 {
2889 if (oldoff > fragP->fr_subtype)
2890 oldoff = 0;
2891 if (newoff > fragP->fr_subtype)
2892 newoff = 0;
2893 }
2894
2895 growth = newoff - oldoff;
2896
2897 /* If this align happens to follow a leb128 and
2898 we have determined that the leb128 is bouncing
2899 in size, then break the cycle by inserting an
2900 extra alignment. */
2901 if (growth < 0
2902 && (rs_leb128_fudge & 16) != 0
2903 && (rs_leb128_fudge & 15) >= 2)
2904 {
2905 segment_info_type *seginfo = seg_info (segment);
2906 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2907 struct frag *newf;
2908
2909 newf = frag_alloc (ob);
2910 obstack_blank_fast (ob, fragP->fr_var);
2911 obstack_finish (ob);
2912 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2913 memcpy (newf->fr_literal,
2914 fragP->fr_literal + fragP->fr_fix,
2915 fragP->fr_var);
2916 newf->fr_type = rs_fill;
2917 newf->fr_address = address + fragP->fr_fix + newoff;
2918 newf->fr_fix = 0;
2919 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2920 / fragP->fr_var);
2921 if (newf->fr_offset * newf->fr_var
2922 != (offsetT) 1 << fragP->fr_offset)
2923 {
2924 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2925 newf->fr_var = 1;
2926 }
2927 /* Include size of new frag in GROWTH. */
2928 growth += newf->fr_offset * newf->fr_var;
2929 /* Adjust the new frag address for the amount
2930 we'll add when we process the new frag. */
2931 newf->fr_address -= stretch + growth;
2932 newf->relax_marker ^= 1;
2933 fragP->fr_next = newf;
2934 #ifdef DEBUG
2935 as_warn (_("padding added"));
2936 #endif
2937 }
2938 }
2939 break;
2940
2941 case rs_org:
2942 {
2943 offsetT target = offset;
2944 addressT after;
2945
2946 if (symbolP)
2947 {
2948 /* Convert from an actual address to an octet offset
2949 into the section. Here it is assumed that the
2950 section's VMA is zero, and can omit subtracting it
2951 from the symbol's value to get the address offset. */
2952 know (S_GET_SEGMENT (symbolP)->vma == 0);
2953 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2954 }
2955
2956 know (fragP->fr_next);
2957 after = fragP->fr_next->fr_address + stretch;
2958 growth = target - after;
2959
2960 /* Growth may be negative, but variable part of frag
2961 cannot have fewer than 0 chars. That is, we can't
2962 .org backwards. */
2963 if ((offsetT) (address + fragP->fr_fix) > target)
2964 {
2965 growth = 0;
2966
2967 /* Don't error on first few frag relax passes.
2968 The symbol might be an expression involving
2969 symbol values from other sections. If those
2970 sections have not yet been processed their
2971 frags will all have zero addresses, so we
2972 will calculate incorrect values for them. The
2973 number of passes we allow before giving an
2974 error is somewhat arbitrary. It should be at
2975 least one, with larger values requiring
2976 increasingly contrived dependencies between
2977 frags to trigger a false error. */
2978 if (pass < 2)
2979 {
2980 /* Force another pass. */
2981 ret = 1;
2982 break;
2983 }
2984
2985 as_bad_where (fragP->fr_file, fragP->fr_line,
2986 _("attempt to move .org backwards"));
2987
2988 /* We've issued an error message. Change the
2989 frag to avoid cascading errors. */
2990 fragP->fr_type = rs_align;
2991 fragP->fr_subtype = 0;
2992 fragP->fr_offset = 0;
2993 fragP->fr_fix = after - address;
2994 }
2995 }
2996 break;
2997
2998 case rs_space:
2999 case rs_space_nop:
3000 growth = 0;
3001 if (symbolP)
3002 {
3003 offsetT amount;
3004
3005 amount = S_GET_VALUE (symbolP);
3006 if (S_GET_SEGMENT (symbolP) != absolute_section
3007 || S_IS_COMMON (symbolP)
3008 || ! S_IS_DEFINED (symbolP))
3009 {
3010 as_bad_where (fragP->fr_file, fragP->fr_line,
3011 _(".space specifies non-absolute value"));
3012 /* Prevent repeat of this error message. */
3013 fragP->fr_symbol = 0;
3014 }
3015 else if (amount < 0)
3016 {
3017 /* Don't error on first few frag relax passes.
3018 See rs_org comment for a longer explanation. */
3019 if (pass < 2)
3020 {
3021 ret = 1;
3022 break;
3023 }
3024
3025 as_warn_where (fragP->fr_file, fragP->fr_line,
3026 _(".space, .nops or .fill with negative value, ignored"));
3027 fragP->fr_symbol = 0;
3028 }
3029 else
3030 growth = (was_address + fragP->fr_fix + amount
3031 - fragP->fr_next->fr_address);
3032 }
3033 break;
3034
3035 case rs_machine_dependent:
3036 #ifdef md_relax_frag
3037 growth = md_relax_frag (segment, fragP, stretch);
3038 #else
3039 #ifdef TC_GENERIC_RELAX_TABLE
3040 /* The default way to relax a frag is to look through
3041 TC_GENERIC_RELAX_TABLE. */
3042 growth = md_generic_table_relax_frag (segment, fragP,
3043 stretch);
3044 #endif /* TC_GENERIC_RELAX_TABLE */
3045 #endif
3046 break;
3047
3048 case rs_leb128:
3049 {
3050 valueT value;
3051 offsetT size;
3052
3053 value = resolve_symbol_value (fragP->fr_symbol);
3054 size = sizeof_leb128 (value, fragP->fr_subtype);
3055 growth = size - fragP->fr_offset;
3056 fragP->fr_offset = size;
3057 }
3058 break;
3059
3060 case rs_cfa:
3061 growth = eh_frame_relax_frag (fragP);
3062 break;
3063
3064 case rs_dwarf2dbg:
3065 growth = dwarf2dbg_relax_frag (fragP);
3066 break;
3067
3068 default:
3069 BAD_CASE (fragP->fr_type);
3070 break;
3071 }
3072 if (growth)
3073 {
3074 stretch += growth;
3075 stretched = 1;
3076 if (fragP->fr_type == rs_leb128)
3077 rs_leb128_fudge += 16;
3078 else if (fragP->fr_type == rs_align
3079 && (rs_leb128_fudge & 16) != 0
3080 && stretch == 0)
3081 rs_leb128_fudge += 16;
3082 else
3083 rs_leb128_fudge = 0;
3084 }
3085 }
3086
3087 if (stretch == 0
3088 && (rs_leb128_fudge & 16) == 0
3089 && (rs_leb128_fudge & -16) != 0)
3090 rs_leb128_fudge += 1;
3091 else
3092 rs_leb128_fudge = 0;
3093 }
3094 /* Until nothing further to relax. */
3095 while (stretched && -- max_iterations);
3096
3097 if (stretched)
3098 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
3099 segment_name (segment));
3100 }
3101
3102 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
3103 if (fragP->last_fr_address != fragP->fr_address)
3104 {
3105 fragP->last_fr_address = fragP->fr_address;
3106 ret = 1;
3107 }
3108 return ret;
3109 }
3110
3111 void
3112 number_to_chars_bigendian (char *buf, valueT val, int n)
3113 {
3114 if (n <= 0)
3115 abort ();
3116 while (n--)
3117 {
3118 buf[n] = val & 0xff;
3119 val >>= 8;
3120 }
3121 }
3122
3123 void
3124 number_to_chars_littleendian (char *buf, valueT val, int n)
3125 {
3126 if (n <= 0)
3127 abort ();
3128 while (n--)
3129 {
3130 *buf++ = val & 0xff;
3131 val >>= 8;
3132 }
3133 }
3134
3135 void
3136 write_print_statistics (FILE *file)
3137 {
3138 fprintf (file, "fixups: %d\n", n_fixups);
3139 }
3140
3141 /* For debugging. */
3142 extern int indent_level;
3143
3144 void
3145 print_fixup (fixS *fixp)
3146 {
3147 indent_level = 1;
3148 fprintf (stderr, "fix ");
3149 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
3150 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
3151 if (fixp->fx_pcrel)
3152 fprintf (stderr, " pcrel");
3153 if (fixp->fx_pcrel_adjust)
3154 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
3155 if (fixp->fx_tcbit)
3156 fprintf (stderr, " tcbit");
3157 if (fixp->fx_done)
3158 fprintf (stderr, " done");
3159 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
3160 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
3161 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
3162 (long) fixp->fx_where,
3163 (unsigned long) fixp->fx_offset,
3164 (unsigned long) fixp->fx_addnumber);
3165 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
3166 fixp->fx_r_type);
3167 if (fixp->fx_addsy)
3168 {
3169 fprintf (stderr, "\n +<");
3170 print_symbol_value_1 (stderr, fixp->fx_addsy);
3171 fprintf (stderr, ">");
3172 }
3173 if (fixp->fx_subsy)
3174 {
3175 fprintf (stderr, "\n -<");
3176 print_symbol_value_1 (stderr, fixp->fx_subsy);
3177 fprintf (stderr, ">");
3178 }
3179 fprintf (stderr, "\n");
3180 #ifdef TC_FIX_DATA_PRINT
3181 TC_FIX_DATA_PRINT (stderr, fixp);
3182 #endif
3183 }
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