daily update
[binutils.git] / gas / write.c
blob73eb793e1f07bcc4617ec7c7d60ff56152690010
1 /* write.c - emit .o file
2 Copyright 1986, 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002
4 Free Software Foundation, Inc.
6 This file is part of GAS, the GNU Assembler.
8 GAS is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
13 GAS is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GAS; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 02111-1307, USA. */
23 /* This thing should be set up to do byteordering correctly. But... */
25 #include "as.h"
26 #include "subsegs.h"
27 #include "obstack.h"
28 #include "output-file.h"
29 #include "dwarf2dbg.h"
31 #ifndef TC_ADJUST_RELOC_COUNT
32 #define TC_ADJUST_RELOC_COUNT(FIX, COUNT)
33 #endif
35 #ifndef TC_FORCE_RELOCATION
36 #define TC_FORCE_RELOCATION(FIX) \
37 (S_FORCE_RELOC ((FIX)->fx_addsy))
38 #endif
40 #ifndef TC_FORCE_RELOCATION_ABS
41 #define TC_FORCE_RELOCATION_ABS(FIX) \
42 (TC_FORCE_RELOCATION (FIX))
43 #endif
45 #ifndef TC_FORCE_RELOCATION_LOCAL
46 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
47 (!(FIX)->fx_pcrel \
48 || (FIX)->fx_plt \
49 || TC_FORCE_RELOCATION (FIX))
50 #endif
52 #ifndef TC_FORCE_RELOCATION_SUB_SAME
53 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
54 (! SEG_NORMAL (SEG))
55 #endif
57 #ifndef TC_FORCE_RELOCATION_SUB_ABS
58 #define TC_FORCE_RELOCATION_SUB_ABS(FIX) 0
59 #endif
61 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
62 #ifdef DIFF_EXPR_OK
63 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 0
64 #else
65 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 1
66 #endif
67 #endif
69 #ifndef TC_VALIDATE_FIX_SUB
70 #ifdef UNDEFINED_DIFFERENCE_OK
71 /* The PA needs this for PIC code generation. */
72 #define TC_VALIDATE_FIX_SUB(FIX) 1
73 #else
74 #ifdef BFD_ASSEMBLER
75 #define TC_VALIDATE_FIX_SUB(FIX) \
76 ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
77 || (FIX)->fx_r_type == BFD_RELOC_GPREL16)
78 #else
79 #define TC_VALIDATE_FIX_SUB(FIX) 0
80 #endif
81 #endif
82 #endif
84 #ifndef TC_LINKRELAX_FIXUP
85 #define TC_LINKRELAX_FIXUP(SEG) 1
86 #endif
88 #ifndef MD_APPLY_SYM_VALUE
89 #define MD_APPLY_SYM_VALUE(FIX) 1
90 #endif
92 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
93 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
94 #endif
96 #ifndef MD_PCREL_FROM_SECTION
97 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
98 #endif
100 #ifndef WORKING_DOT_WORD
101 extern const int md_short_jump_size;
102 extern const int md_long_jump_size;
103 #endif
105 /* Used to control final evaluation of expressions. */
106 int finalize_syms = 0;
108 int symbol_table_frozen;
110 symbolS *abs_section_sym;
112 /* Remember the value of dot when parsing expressions. */
113 addressT dot_value;
115 void print_fixup PARAMS ((fixS *));
117 #ifdef BFD_ASSEMBLER
118 static void renumber_sections PARAMS ((bfd *, asection *, PTR));
120 /* We generally attach relocs to frag chains. However, after we have
121 chained these all together into a segment, any relocs we add after
122 that must be attached to a segment. This will include relocs added
123 in md_estimate_size_for_relax, for example. */
124 static int frags_chained = 0;
125 #endif
127 #ifndef BFD_ASSEMBLER
129 #ifndef MANY_SEGMENTS
130 struct frag *text_frag_root;
131 struct frag *data_frag_root;
132 struct frag *bss_frag_root;
134 struct frag *text_last_frag; /* Last frag in segment. */
135 struct frag *data_last_frag; /* Last frag in segment. */
136 static struct frag *bss_last_frag; /* Last frag in segment. */
137 #endif
139 #ifndef BFD
140 static object_headers headers;
141 #endif
143 long string_byte_count;
144 char *next_object_file_charP; /* Tracks object file bytes. */
146 #ifndef OBJ_VMS
147 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
148 #endif
150 #endif /* BFD_ASSEMBLER */
152 static int n_fixups;
154 #ifdef BFD_ASSEMBLER
155 #define RELOC_ENUM enum bfd_reloc_code_real
156 #else
157 #define RELOC_ENUM int
158 #endif
160 static fixS *fix_new_internal PARAMS ((fragS *, int where, int size,
161 symbolS *add, symbolS *sub,
162 offsetT offset, int pcrel,
163 RELOC_ENUM r_type));
164 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
165 static long fixup_segment PARAMS ((fixS *, segT));
166 #endif
167 static relax_addressT relax_align PARAMS ((relax_addressT addr, int align));
168 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
169 static fragS *chain_frchains_together_1 PARAMS ((segT, struct frchain *));
170 #endif
171 #ifdef BFD_ASSEMBLER
172 static void chain_frchains_together PARAMS ((bfd *, segT, PTR));
173 static void cvt_frag_to_fill PARAMS ((segT, fragS *));
174 static void adjust_reloc_syms PARAMS ((bfd *, asection *, PTR));
175 static void fix_segment PARAMS ((bfd *, asection *, PTR));
176 static void write_relocs PARAMS ((bfd *, asection *, PTR));
177 static void write_contents PARAMS ((bfd *, asection *, PTR));
178 static void set_symtab PARAMS ((void));
179 #endif
180 #if defined (BFD_ASSEMBLER) || (! defined (BFD) && ! defined (OBJ_AOUT))
181 static void merge_data_into_text PARAMS ((void));
182 #endif
183 #if ! defined (BFD_ASSEMBLER) && ! defined (BFD)
184 static void cvt_frag_to_fill PARAMS ((object_headers *, segT, fragS *));
185 static void remove_subsegs PARAMS ((frchainS *, int, fragS **, fragS **));
186 static void relax_and_size_all_segments PARAMS ((void));
187 #endif
189 /* Create a fixS in obstack 'notes'. */
191 static fixS *
192 fix_new_internal (frag, where, size, add_symbol, sub_symbol, offset, pcrel,
193 r_type)
194 fragS *frag; /* Which frag? */
195 int where; /* Where in that frag? */
196 int size; /* 1, 2, or 4 usually. */
197 symbolS *add_symbol; /* X_add_symbol. */
198 symbolS *sub_symbol; /* X_op_symbol. */
199 offsetT offset; /* X_add_number. */
200 int pcrel; /* TRUE if PC-relative relocation. */
201 RELOC_ENUM r_type ATTRIBUTE_UNUSED; /* Relocation type. */
203 fixS *fixP;
205 n_fixups++;
207 fixP = (fixS *) obstack_alloc (&notes, sizeof (fixS));
209 fixP->fx_frag = frag;
210 fixP->fx_where = where;
211 fixP->fx_size = size;
212 /* We've made fx_size a narrow field; check that it's wide enough. */
213 if (fixP->fx_size != size)
215 as_bad (_("field fx_size too small to hold %d"), size);
216 abort ();
218 fixP->fx_addsy = add_symbol;
219 fixP->fx_subsy = sub_symbol;
220 fixP->fx_offset = offset;
221 fixP->fx_dot_value = dot_value;
222 fixP->fx_pcrel = pcrel;
223 fixP->fx_plt = 0;
224 #if defined(NEED_FX_R_TYPE) || defined (BFD_ASSEMBLER)
225 fixP->fx_r_type = r_type;
226 #endif
227 fixP->fx_im_disp = 0;
228 fixP->fx_pcrel_adjust = 0;
229 fixP->fx_bit_fixP = 0;
230 fixP->fx_addnumber = 0;
231 fixP->fx_tcbit = 0;
232 fixP->fx_done = 0;
233 fixP->fx_no_overflow = 0;
234 fixP->fx_signed = 0;
236 #ifdef USING_CGEN
237 fixP->fx_cgen.insn = NULL;
238 fixP->fx_cgen.opinfo = 0;
239 #endif
241 #ifdef TC_FIX_TYPE
242 TC_INIT_FIX_DATA (fixP);
243 #endif
245 as_where (&fixP->fx_file, &fixP->fx_line);
247 /* Usually, we want relocs sorted numerically, but while
248 comparing to older versions of gas that have relocs
249 reverse sorted, it is convenient to have this compile
250 time option. xoxorich. */
253 #ifdef BFD_ASSEMBLER
254 fixS **seg_fix_rootP = (frags_chained
255 ? &seg_info (now_seg)->fix_root
256 : &frchain_now->fix_root);
257 fixS **seg_fix_tailP = (frags_chained
258 ? &seg_info (now_seg)->fix_tail
259 : &frchain_now->fix_tail);
260 #endif
262 #ifdef REVERSE_SORT_RELOCS
264 fixP->fx_next = *seg_fix_rootP;
265 *seg_fix_rootP = fixP;
267 #else /* REVERSE_SORT_RELOCS */
269 fixP->fx_next = NULL;
271 if (*seg_fix_tailP)
272 (*seg_fix_tailP)->fx_next = fixP;
273 else
274 *seg_fix_rootP = fixP;
275 *seg_fix_tailP = fixP;
277 #endif /* REVERSE_SORT_RELOCS */
280 return fixP;
283 /* Create a fixup relative to a symbol (plus a constant). */
285 fixS *
286 fix_new (frag, where, size, add_symbol, offset, pcrel, r_type)
287 fragS *frag; /* Which frag? */
288 int where; /* Where in that frag? */
289 int size; /* 1, 2, or 4 usually. */
290 symbolS *add_symbol; /* X_add_symbol. */
291 offsetT offset; /* X_add_number. */
292 int pcrel; /* TRUE if PC-relative relocation. */
293 RELOC_ENUM r_type; /* Relocation type. */
295 return fix_new_internal (frag, where, size, add_symbol,
296 (symbolS *) NULL, offset, pcrel, r_type);
299 /* Create a fixup for an expression. Currently we only support fixups
300 for difference expressions. That is itself more than most object
301 file formats support anyhow. */
303 fixS *
304 fix_new_exp (frag, where, size, exp, pcrel, r_type)
305 fragS *frag; /* Which frag? */
306 int where; /* Where in that frag? */
307 int size; /* 1, 2, or 4 usually. */
308 expressionS *exp; /* Expression. */
309 int pcrel; /* TRUE if PC-relative relocation. */
310 RELOC_ENUM r_type; /* Relocation type. */
312 symbolS *add = NULL;
313 symbolS *sub = NULL;
314 offsetT off = 0;
316 switch (exp->X_op)
318 case O_absent:
319 break;
321 case O_register:
322 as_bad (_("register value used as expression"));
323 break;
325 case O_add:
326 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
327 the difference expression cannot immediately be reduced. */
329 symbolS *stmp = make_expr_symbol (exp);
331 exp->X_op = O_symbol;
332 exp->X_op_symbol = 0;
333 exp->X_add_symbol = stmp;
334 exp->X_add_number = 0;
336 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
339 case O_symbol_rva:
340 add = exp->X_add_symbol;
341 off = exp->X_add_number;
343 #if defined(BFD_ASSEMBLER)
344 r_type = BFD_RELOC_RVA;
345 #else
346 #if defined(TC_RVA_RELOC)
347 r_type = TC_RVA_RELOC;
348 #else
349 as_fatal (_("rva not supported"));
350 #endif
351 #endif
352 break;
354 case O_uminus:
355 sub = exp->X_add_symbol;
356 off = exp->X_add_number;
357 break;
359 case O_subtract:
360 sub = exp->X_op_symbol;
361 /* Fall through. */
362 case O_symbol:
363 add = exp->X_add_symbol;
364 /* Fall through. */
365 case O_constant:
366 off = exp->X_add_number;
367 break;
369 default:
370 add = make_expr_symbol (exp);
371 break;
374 return fix_new_internal (frag, where, size, add, sub, off, pcrel, r_type);
377 /* Append a string onto another string, bumping the pointer along. */
378 void
379 append (charPP, fromP, length)
380 char **charPP;
381 char *fromP;
382 unsigned long length;
384 /* Don't trust memcpy() of 0 chars. */
385 if (length == 0)
386 return;
388 memcpy (*charPP, fromP, length);
389 *charPP += length;
392 #ifndef BFD_ASSEMBLER
393 int section_alignment[SEG_MAXIMUM_ORDINAL];
394 #endif
396 /* This routine records the largest alignment seen for each segment.
397 If the beginning of the segment is aligned on the worst-case
398 boundary, all of the other alignments within it will work. At
399 least one object format really uses this info. */
401 void
402 record_alignment (seg, align)
403 /* Segment to which alignment pertains. */
404 segT seg;
405 /* Alignment, as a power of 2 (e.g., 1 => 2-byte boundary, 2 => 4-byte
406 boundary, etc.) */
407 int align;
409 if (seg == absolute_section)
410 return;
411 #ifdef BFD_ASSEMBLER
412 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
413 bfd_set_section_alignment (stdoutput, seg, align);
414 #else
415 if (align > section_alignment[(int) seg])
416 section_alignment[(int) seg] = align;
417 #endif
421 get_recorded_alignment (seg)
422 segT seg;
424 if (seg == absolute_section)
425 return 0;
426 #ifdef BFD_ASSEMBLER
427 return bfd_get_section_alignment (stdoutput, seg);
428 #else
429 return section_alignment[(int) seg];
430 #endif
433 #ifdef BFD_ASSEMBLER
435 /* Reset the section indices after removing the gas created sections. */
437 static void
438 renumber_sections (abfd, sec, countparg)
439 bfd *abfd ATTRIBUTE_UNUSED;
440 asection *sec;
441 PTR countparg;
443 int *countp = (int *) countparg;
445 sec->index = *countp;
446 ++*countp;
449 #endif /* defined (BFD_ASSEMBLER) */
451 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
453 static fragS *
454 chain_frchains_together_1 (section, frchp)
455 segT section;
456 struct frchain *frchp;
458 fragS dummy, *prev_frag = &dummy;
459 #ifdef BFD_ASSEMBLER
460 fixS fix_dummy, *prev_fix = &fix_dummy;
461 #endif
463 for (; frchp && frchp->frch_seg == section; frchp = frchp->frch_next)
465 prev_frag->fr_next = frchp->frch_root;
466 prev_frag = frchp->frch_last;
467 assert (prev_frag->fr_type != 0);
468 #ifdef BFD_ASSEMBLER
469 if (frchp->fix_root != (fixS *) NULL)
471 if (seg_info (section)->fix_root == (fixS *) NULL)
472 seg_info (section)->fix_root = frchp->fix_root;
473 prev_fix->fx_next = frchp->fix_root;
474 seg_info (section)->fix_tail = frchp->fix_tail;
475 prev_fix = frchp->fix_tail;
477 #endif
479 assert (prev_frag->fr_type != 0);
480 prev_frag->fr_next = 0;
481 return prev_frag;
484 #endif
486 #ifdef BFD_ASSEMBLER
488 static void
489 chain_frchains_together (abfd, section, xxx)
490 bfd *abfd ATTRIBUTE_UNUSED;
491 segT section;
492 PTR xxx ATTRIBUTE_UNUSED;
494 segment_info_type *info;
496 /* BFD may have introduced its own sections without using
497 subseg_new, so it is possible that seg_info is NULL. */
498 info = seg_info (section);
499 if (info != (segment_info_type *) NULL)
500 info->frchainP->frch_last
501 = chain_frchains_together_1 (section, info->frchainP);
503 /* Now that we've chained the frags together, we must add new fixups
504 to the segment, not to the frag chain. */
505 frags_chained = 1;
508 #endif
510 #if !defined (BFD) && !defined (BFD_ASSEMBLER)
512 static void
513 remove_subsegs (head, seg, root, last)
514 frchainS *head;
515 int seg;
516 fragS **root;
517 fragS **last;
519 *root = head->frch_root;
520 *last = chain_frchains_together_1 (seg, head);
523 #endif /* BFD */
525 #if defined (BFD_ASSEMBLER) || !defined (BFD)
527 #ifdef BFD_ASSEMBLER
528 static void
529 cvt_frag_to_fill (sec, fragP)
530 segT sec ATTRIBUTE_UNUSED;
531 fragS *fragP;
532 #else
533 static void
534 cvt_frag_to_fill (headersP, sec, fragP)
535 object_headers *headersP;
536 segT sec;
537 fragS *fragP;
538 #endif
540 switch (fragP->fr_type)
542 case rs_align:
543 case rs_align_code:
544 case rs_align_test:
545 case rs_org:
546 case rs_space:
547 #ifdef HANDLE_ALIGN
548 HANDLE_ALIGN (fragP);
549 #endif
550 know (fragP->fr_next != NULL);
551 fragP->fr_offset = (fragP->fr_next->fr_address
552 - fragP->fr_address
553 - fragP->fr_fix) / fragP->fr_var;
554 if (fragP->fr_offset < 0)
556 as_bad_where (fragP->fr_file, fragP->fr_line,
557 _("attempt to .org/.space backwards? (%ld)"),
558 (long) fragP->fr_offset);
559 fragP->fr_offset = 0;
561 fragP->fr_type = rs_fill;
562 break;
564 case rs_fill:
565 break;
567 case rs_leb128:
569 valueT value = S_GET_VALUE (fragP->fr_symbol);
570 int size;
572 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
573 fragP->fr_subtype);
575 fragP->fr_fix += size;
576 fragP->fr_type = rs_fill;
577 fragP->fr_var = 0;
578 fragP->fr_offset = 0;
579 fragP->fr_symbol = NULL;
581 break;
583 case rs_cfa:
584 eh_frame_convert_frag (fragP);
585 break;
587 case rs_dwarf2dbg:
588 dwarf2dbg_convert_frag (fragP);
589 break;
591 case rs_machine_dependent:
592 #ifdef BFD_ASSEMBLER
593 md_convert_frag (stdoutput, sec, fragP);
594 #else
595 md_convert_frag (headersP, sec, fragP);
596 #endif
598 assert (fragP->fr_next == NULL
599 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
600 == fragP->fr_fix));
602 /* After md_convert_frag, we make the frag into a ".space 0".
603 md_convert_frag() should set up any fixSs and constants
604 required. */
605 frag_wane (fragP);
606 break;
608 #ifndef WORKING_DOT_WORD
609 case rs_broken_word:
611 struct broken_word *lie;
613 if (fragP->fr_subtype)
615 fragP->fr_fix += md_short_jump_size;
616 for (lie = (struct broken_word *) (fragP->fr_symbol);
617 lie && lie->dispfrag == fragP;
618 lie = lie->next_broken_word)
619 if (lie->added == 1)
620 fragP->fr_fix += md_long_jump_size;
622 frag_wane (fragP);
624 break;
625 #endif
627 default:
628 BAD_CASE (fragP->fr_type);
629 break;
633 #endif /* defined (BFD_ASSEMBLER) || !defined (BFD) */
635 #ifdef BFD_ASSEMBLER
636 static void relax_seg PARAMS ((bfd *, asection *, PTR));
637 static void
638 relax_seg (abfd, sec, xxx)
639 bfd *abfd ATTRIBUTE_UNUSED;
640 asection *sec;
641 PTR xxx;
643 segment_info_type *seginfo = seg_info (sec);
645 if (seginfo && seginfo->frchainP
646 && relax_segment (seginfo->frchainP->frch_root, sec))
648 int *result = (int *) xxx;
649 *result = 1;
653 static void size_seg PARAMS ((bfd *, asection *, PTR));
654 static void
655 size_seg (abfd, sec, xxx)
656 bfd *abfd;
657 asection *sec;
658 PTR xxx ATTRIBUTE_UNUSED;
660 flagword flags;
661 fragS *fragp;
662 segment_info_type *seginfo;
663 int x;
664 valueT size, newsize;
666 subseg_change (sec, 0);
668 seginfo = seg_info (sec);
669 if (seginfo && seginfo->frchainP)
671 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
672 cvt_frag_to_fill (sec, fragp);
673 for (fragp = seginfo->frchainP->frch_root;
674 fragp->fr_next;
675 fragp = fragp->fr_next)
676 /* Walk to last elt. */
678 size = fragp->fr_address + fragp->fr_fix;
680 else
681 size = 0;
683 flags = bfd_get_section_flags (abfd, sec);
685 if (size > 0 && ! seginfo->bss)
686 flags |= SEC_HAS_CONTENTS;
688 /* @@ This is just an approximation. */
689 if (seginfo && seginfo->fix_root)
690 flags |= SEC_RELOC;
691 else
692 flags &= ~SEC_RELOC;
693 x = bfd_set_section_flags (abfd, sec, flags);
694 assert (x == true);
696 newsize = md_section_align (sec, size);
697 x = bfd_set_section_size (abfd, sec, newsize);
698 assert (x == true);
700 /* If the size had to be rounded up, add some padding in the last
701 non-empty frag. */
702 assert (newsize >= size);
703 if (size != newsize)
705 fragS *last = seginfo->frchainP->frch_last;
706 fragp = seginfo->frchainP->frch_root;
707 while (fragp->fr_next != last)
708 fragp = fragp->fr_next;
709 last->fr_address = size;
710 if ((newsize - size) % fragp->fr_var == 0)
711 fragp->fr_offset += (newsize - size) / fragp->fr_var;
712 else
713 /* If we hit this abort, it's likely due to subsegs_finish not
714 providing sufficient alignment on the last frag, and the
715 machine dependent code using alignment frags with fr_var
716 greater than 1. */
717 abort ();
720 #ifdef tc_frob_section
721 tc_frob_section (sec);
722 #endif
723 #ifdef obj_frob_section
724 obj_frob_section (sec);
725 #endif
728 #ifdef DEBUG2
729 static void
730 dump_section_relocs (abfd, sec, stream_)
731 bfd *abfd ATTRIBUTE_UNUSED;
732 asection *sec;
733 char *stream_;
735 FILE *stream = (FILE *) stream_;
736 segment_info_type *seginfo = seg_info (sec);
737 fixS *fixp = seginfo->fix_root;
739 if (!fixp)
740 return;
742 fprintf (stream, "sec %s relocs:\n", sec->name);
743 while (fixp)
745 symbolS *s = fixp->fx_addsy;
747 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
748 (int) fixp->fx_r_type);
749 if (s == NULL)
750 fprintf (stream, "no sym\n");
751 else
753 print_symbol_value_1 (stream, s);
754 fprintf (stream, "\n");
756 fixp = fixp->fx_next;
759 #else
760 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
761 #endif
763 #ifndef EMIT_SECTION_SYMBOLS
764 #define EMIT_SECTION_SYMBOLS 1
765 #endif
767 /* This pass over fixups decides whether symbols can be replaced with
768 section symbols. */
770 static void
771 adjust_reloc_syms (abfd, sec, xxx)
772 bfd *abfd ATTRIBUTE_UNUSED;
773 asection *sec;
774 PTR xxx ATTRIBUTE_UNUSED;
776 segment_info_type *seginfo = seg_info (sec);
777 fixS *fixp;
779 if (seginfo == NULL)
780 return;
782 dump_section_relocs (abfd, sec, stderr);
784 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
785 if (fixp->fx_done)
786 /* Ignore it. */
788 else if (fixp->fx_addsy)
790 symbolS *sym;
791 asection *symsec;
793 #ifdef DEBUG5
794 fprintf (stderr, "\n\nadjusting fixup:\n");
795 print_fixup (fixp);
796 #endif
798 sym = fixp->fx_addsy;
800 /* All symbols should have already been resolved at this
801 point. It is possible to see unresolved expression
802 symbols, though, since they are not in the regular symbol
803 table. */
804 resolve_symbol_value (sym);
806 if (fixp->fx_subsy != NULL)
807 resolve_symbol_value (fixp->fx_subsy);
809 /* If this symbol is equated to an undefined symbol, convert
810 the fixup to being against that symbol. */
811 if (symbol_equated_reloc_p (sym))
813 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
814 sym = symbol_get_value_expression (sym)->X_add_symbol;
815 fixp->fx_addsy = sym;
818 if (symbol_mri_common_p (sym))
820 /* These symbols are handled specially in fixup_segment. */
821 continue;
824 /* If the symbol is undefined, common, weak, or global (ELF
825 shared libs), we can't replace it with the section symbol. */
826 if (S_FORCE_RELOC (fixp->fx_addsy))
827 continue;
829 /* Is there some other (target cpu dependent) reason we can't adjust
830 this one? (E.g. relocations involving function addresses on
831 the PA. */
832 #ifdef tc_fix_adjustable
833 if (! tc_fix_adjustable (fixp))
834 continue;
835 #endif
837 /* Since we're reducing to section symbols, don't attempt to reduce
838 anything that's already using one. */
839 if (symbol_section_p (sym))
840 continue;
842 symsec = S_GET_SEGMENT (sym);
843 if (symsec == NULL)
844 abort ();
846 if (bfd_is_abs_section (symsec))
848 /* The fixup_segment routine normally will not use this
849 symbol in a relocation. */
850 continue;
853 /* Don't try to reduce relocs which refer to non-local symbols
854 in .linkonce sections. It can lead to confusion when a
855 debugging section refers to a .linkonce section. I hope
856 this will always be correct. */
857 if (symsec != sec && ! S_IS_LOCAL (sym))
859 if ((symsec->flags & SEC_LINK_ONCE) != 0
860 || (IS_ELF
861 /* The GNU toolchain uses an extension for ELF: a
862 section beginning with the magic string
863 .gnu.linkonce is a linkonce section. */
864 && strncmp (segment_name (symsec), ".gnu.linkonce",
865 sizeof ".gnu.linkonce" - 1) == 0))
866 continue;
869 /* Never adjust a reloc against local symbol in a merge section
870 with non-zero addend. */
871 if ((symsec->flags & SEC_MERGE) != 0 && fixp->fx_offset != 0)
872 continue;
874 /* Never adjust a reloc against TLS local symbol. */
875 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
876 continue;
878 /* We refetch the segment when calling section_symbol, rather
879 than using symsec, because S_GET_VALUE may wind up changing
880 the section when it calls resolve_symbol_value. */
881 fixp->fx_offset += S_GET_VALUE (sym);
882 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
883 #ifdef DEBUG5
884 fprintf (stderr, "\nadjusted fixup:\n");
885 print_fixup (fixp);
886 #endif
889 dump_section_relocs (abfd, sec, stderr);
892 static void
893 fix_segment (abfd, sec, xxx)
894 bfd *abfd ATTRIBUTE_UNUSED;
895 asection *sec;
896 PTR xxx ATTRIBUTE_UNUSED;
898 segment_info_type *seginfo = seg_info (sec);
900 fixup_segment (seginfo->fix_root, sec);
903 static void
904 write_relocs (abfd, sec, xxx)
905 bfd *abfd;
906 asection *sec;
907 PTR xxx ATTRIBUTE_UNUSED;
909 segment_info_type *seginfo = seg_info (sec);
910 unsigned int i;
911 unsigned int n;
912 arelent **relocs;
913 fixS *fixp;
914 char *err;
916 /* If seginfo is NULL, we did not create this section; don't do
917 anything with it. */
918 if (seginfo == NULL)
919 return;
921 n = 0;
922 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
923 n++;
925 #ifndef RELOC_EXPANSION_POSSIBLE
926 /* Set up reloc information as well. */
927 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
928 memset ((char *) relocs, 0, n * sizeof (arelent *));
930 i = 0;
931 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
933 arelent *reloc;
934 bfd_reloc_status_type s;
935 symbolS *sym;
937 if (fixp->fx_done)
939 n--;
940 continue;
943 /* If this is an undefined symbol which was equated to another
944 symbol, then generate the reloc against the latter symbol
945 rather than the former. */
946 sym = fixp->fx_addsy;
947 while (symbol_equated_reloc_p (sym))
949 symbolS *n;
951 /* We must avoid looping, as that can occur with a badly
952 written program. */
953 n = symbol_get_value_expression (sym)->X_add_symbol;
954 if (n == sym)
955 break;
956 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
957 sym = n;
959 fixp->fx_addsy = sym;
961 reloc = tc_gen_reloc (sec, fixp);
962 if (!reloc)
964 n--;
965 continue;
968 #if 0
969 /* This test is triggered inappropriately for the SH. */
970 if (fixp->fx_where + fixp->fx_size
971 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
972 abort ();
973 #endif
975 s = bfd_install_relocation (stdoutput, reloc,
976 fixp->fx_frag->fr_literal,
977 fixp->fx_frag->fr_address,
978 sec, &err);
979 switch (s)
981 case bfd_reloc_ok:
982 break;
983 case bfd_reloc_overflow:
984 as_bad_where (fixp->fx_file, fixp->fx_line,
985 _("relocation overflow"));
986 break;
987 case bfd_reloc_outofrange:
988 as_bad_where (fixp->fx_file, fixp->fx_line,
989 _("relocation out of range"));
990 break;
991 default:
992 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
993 fixp->fx_file, fixp->fx_line, s);
995 relocs[i++] = reloc;
997 #else
998 n = n * MAX_RELOC_EXPANSION;
999 /* Set up reloc information as well. */
1000 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
1002 i = 0;
1003 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
1005 arelent **reloc;
1006 char *data;
1007 bfd_reloc_status_type s;
1008 symbolS *sym;
1009 int j;
1011 if (fixp->fx_done)
1013 n--;
1014 continue;
1017 /* If this is an undefined symbol which was equated to another
1018 symbol, then generate the reloc against the latter symbol
1019 rather than the former. */
1020 sym = fixp->fx_addsy;
1021 while (symbol_equated_reloc_p (sym))
1023 symbolS *n;
1025 /* We must avoid looping, as that can occur with a badly
1026 written program. */
1027 n = symbol_get_value_expression (sym)->X_add_symbol;
1028 if (n == sym)
1029 break;
1030 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
1031 sym = n;
1033 fixp->fx_addsy = sym;
1035 reloc = tc_gen_reloc (sec, fixp);
1037 for (j = 0; reloc[j]; j++)
1039 relocs[i++] = reloc[j];
1040 assert (i <= n);
1042 data = fixp->fx_frag->fr_literal + fixp->fx_where;
1043 if (fixp->fx_where + fixp->fx_size
1044 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
1045 as_bad_where (fixp->fx_file, fixp->fx_line,
1046 _("internal error: fixup not contained within frag"));
1047 for (j = 0; reloc[j]; j++)
1049 s = bfd_install_relocation (stdoutput, reloc[j],
1050 fixp->fx_frag->fr_literal,
1051 fixp->fx_frag->fr_address,
1052 sec, &err);
1053 switch (s)
1055 case bfd_reloc_ok:
1056 break;
1057 case bfd_reloc_overflow:
1058 as_bad_where (fixp->fx_file, fixp->fx_line,
1059 _("relocation overflow"));
1060 break;
1061 case bfd_reloc_outofrange:
1062 as_bad_where (fixp->fx_file, fixp->fx_line,
1063 _("relocation out of range"));
1064 break;
1065 default:
1066 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1067 fixp->fx_file, fixp->fx_line, s);
1071 n = i;
1072 #endif
1074 #ifdef DEBUG4
1076 int i, j, nsyms;
1077 asymbol **sympp;
1078 sympp = bfd_get_outsymbols (stdoutput);
1079 nsyms = bfd_get_symcount (stdoutput);
1080 for (i = 0; i < n; i++)
1081 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1083 for (j = 0; j < nsyms; j++)
1084 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1085 break;
1086 if (j == nsyms)
1087 abort ();
1090 #endif
1092 if (n)
1093 bfd_set_reloc (stdoutput, sec, relocs, n);
1094 else
1095 bfd_set_section_flags (abfd, sec,
1096 (bfd_get_section_flags (abfd, sec)
1097 & (flagword) ~SEC_RELOC));
1099 #ifdef SET_SECTION_RELOCS
1100 SET_SECTION_RELOCS (sec, relocs, n);
1101 #endif
1103 #ifdef DEBUG3
1105 int i;
1106 arelent *r;
1107 asymbol *s;
1108 fprintf (stderr, "relocs for sec %s\n", sec->name);
1109 for (i = 0; i < n; i++)
1111 r = relocs[i];
1112 s = *r->sym_ptr_ptr;
1113 fprintf (stderr, " reloc %2d @%08x off %4x : sym %-10s addend %x\n",
1114 i, r, r->address, s->name, r->addend);
1117 #endif
1120 static void
1121 write_contents (abfd, sec, xxx)
1122 bfd *abfd ATTRIBUTE_UNUSED;
1123 asection *sec;
1124 PTR xxx ATTRIBUTE_UNUSED;
1126 segment_info_type *seginfo = seg_info (sec);
1127 unsigned long offset = 0;
1128 fragS *f;
1130 /* Write out the frags. */
1131 if (seginfo == NULL
1132 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1133 return;
1135 for (f = seginfo->frchainP->frch_root;
1137 f = f->fr_next)
1139 int x;
1140 unsigned long fill_size;
1141 char *fill_literal;
1142 long count;
1144 assert (f->fr_type == rs_fill);
1145 if (f->fr_fix)
1147 x = bfd_set_section_contents (stdoutput, sec,
1148 f->fr_literal, (file_ptr) offset,
1149 (bfd_size_type) f->fr_fix);
1150 if (x == false)
1152 bfd_perror (stdoutput->filename);
1153 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1154 exit (EXIT_FAILURE);
1156 offset += f->fr_fix;
1158 fill_literal = f->fr_literal + f->fr_fix;
1159 fill_size = f->fr_var;
1160 count = f->fr_offset;
1161 assert (count >= 0);
1162 if (fill_size && count)
1164 char buf[256];
1165 if (fill_size > sizeof (buf))
1167 /* Do it the old way. Can this ever happen? */
1168 while (count--)
1170 x = bfd_set_section_contents (stdoutput, sec,
1171 fill_literal,
1172 (file_ptr) offset,
1173 (bfd_size_type) fill_size);
1174 if (x == false)
1176 bfd_perror (stdoutput->filename);
1177 as_perror (_("FATAL: Can't write %s"),
1178 stdoutput->filename);
1179 exit (EXIT_FAILURE);
1181 offset += fill_size;
1184 else
1186 /* Build a buffer full of fill objects and output it as
1187 often as necessary. This saves on the overhead of
1188 potentially lots of bfd_set_section_contents calls. */
1189 int n_per_buf, i;
1190 if (fill_size == 1)
1192 n_per_buf = sizeof (buf);
1193 memset (buf, *fill_literal, n_per_buf);
1195 else
1197 char *bufp;
1198 n_per_buf = sizeof (buf) / fill_size;
1199 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1200 memcpy (bufp, fill_literal, fill_size);
1202 for (; count > 0; count -= n_per_buf)
1204 n_per_buf = n_per_buf > count ? count : n_per_buf;
1205 x = bfd_set_section_contents
1206 (stdoutput, sec, buf, (file_ptr) offset,
1207 (bfd_size_type) n_per_buf * fill_size);
1208 if (x != true)
1209 as_fatal (_("cannot write to output file"));
1210 offset += n_per_buf * fill_size;
1216 #endif
1218 #if defined(BFD_ASSEMBLER) || (!defined (BFD) && !defined(OBJ_AOUT))
1219 static void
1220 merge_data_into_text ()
1222 #if defined(BFD_ASSEMBLER) || defined(MANY_SEGMENTS)
1223 seg_info (text_section)->frchainP->frch_last->fr_next =
1224 seg_info (data_section)->frchainP->frch_root;
1225 seg_info (text_section)->frchainP->frch_last =
1226 seg_info (data_section)->frchainP->frch_last;
1227 seg_info (data_section)->frchainP = 0;
1228 #else
1229 fixS *tmp;
1231 text_last_frag->fr_next = data_frag_root;
1232 text_last_frag = data_last_frag;
1233 data_last_frag = NULL;
1234 data_frag_root = NULL;
1235 if (text_fix_root)
1237 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
1238 tmp->fx_next = data_fix_root;
1239 text_fix_tail = data_fix_tail;
1241 else
1242 text_fix_root = data_fix_root;
1243 data_fix_root = NULL;
1244 #endif
1246 #endif /* BFD_ASSEMBLER || (! BFD && ! OBJ_AOUT) */
1248 #if !defined (BFD_ASSEMBLER) && !defined (BFD)
1249 static void
1250 relax_and_size_all_segments ()
1252 fragS *fragP;
1254 relax_segment (text_frag_root, SEG_TEXT);
1255 relax_segment (data_frag_root, SEG_DATA);
1256 relax_segment (bss_frag_root, SEG_BSS);
1258 /* Now the addresses of frags are correct within the segment. */
1259 know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
1260 H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
1261 text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
1263 /* Join the 2 segments into 1 huge segment.
1264 To do this, re-compute every rn_address in the SEG_DATA frags.
1265 Then join the data frags after the text frags.
1267 Determine a_data [length of data segment]. */
1268 if (data_frag_root)
1270 register relax_addressT slide;
1272 know ((text_last_frag->fr_type == rs_fill)
1273 && (text_last_frag->fr_offset == 0));
1275 H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
1276 data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
1277 slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
1278 #ifdef OBJ_BOUT
1279 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
1280 /* For b.out: If the data section has a strict alignment
1281 requirement, its load address in the .o file will be
1282 rounded up from the size of the text section. These
1283 two values are *not* the same! Similarly for the bss
1284 section.... */
1285 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
1286 #endif
1288 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
1289 fragP->fr_address += slide;
1291 know (text_last_frag != 0);
1292 text_last_frag->fr_next = data_frag_root;
1294 else
1296 H_SET_DATA_SIZE (&headers, 0);
1299 #ifdef OBJ_BOUT
1300 /* See above comments on b.out data section address. */
1302 long bss_vma;
1303 if (data_last_frag == 0)
1304 bss_vma = H_GET_TEXT_SIZE (&headers);
1305 else
1306 bss_vma = data_last_frag->fr_address;
1307 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
1308 bss_address_frag.fr_address = bss_vma;
1310 #else /* ! OBJ_BOUT */
1311 bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
1312 H_GET_DATA_SIZE (&headers));
1314 #endif /* ! OBJ_BOUT */
1316 /* Slide all the frags. */
1317 if (bss_frag_root)
1319 relax_addressT slide = bss_address_frag.fr_address;
1321 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
1322 fragP->fr_address += slide;
1325 if (bss_last_frag)
1326 H_SET_BSS_SIZE (&headers,
1327 bss_last_frag->fr_address - bss_frag_root->fr_address);
1328 else
1329 H_SET_BSS_SIZE (&headers, 0);
1331 #endif /* ! BFD_ASSEMBLER && ! BFD */
1333 #if defined (BFD_ASSEMBLER) || !defined (BFD)
1335 #ifdef BFD_ASSEMBLER
1336 static void
1337 set_symtab ()
1339 int nsyms;
1340 asymbol **asympp;
1341 symbolS *symp;
1342 boolean result;
1343 extern PTR bfd_alloc PARAMS ((bfd *, bfd_size_type));
1345 /* Count symbols. We can't rely on a count made by the loop in
1346 write_object_file, because *_frob_file may add a new symbol or
1347 two. */
1348 nsyms = 0;
1349 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1350 nsyms++;
1352 if (nsyms)
1354 int i;
1355 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1357 asympp = (asymbol **) bfd_alloc (stdoutput, amt);
1358 symp = symbol_rootP;
1359 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1361 asympp[i] = symbol_get_bfdsym (symp);
1362 symbol_mark_written (symp);
1365 else
1366 asympp = 0;
1367 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1368 assert (result == true);
1369 symbol_table_frozen = 1;
1371 #endif
1373 /* Finish the subsegments. After every sub-segment, we fake an
1374 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1375 ".fill 0" because that is the kind of frag that requires least
1376 thought. ".align" frags like to have a following frag since that
1377 makes calculating their intended length trivial. */
1379 #ifndef SUB_SEGMENT_ALIGN
1380 #ifdef HANDLE_ALIGN
1381 /* The last subsegment gets an aligment corresponding to the alignment
1382 of the section. This allows proper nop-filling at the end of
1383 code-bearing sections. */
1384 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1385 (!(FRCHAIN)->frch_next || (FRCHAIN)->frch_next->frch_seg != (SEG) \
1386 ? get_recorded_alignment (SEG) : 0)
1387 #else
1388 #ifdef BFD_ASSEMBLER
1389 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1390 #else
1391 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 2
1392 #endif
1393 #endif
1394 #endif
1396 void
1397 subsegs_finish ()
1399 struct frchain *frchainP;
1401 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
1403 int alignment = 0;
1405 subseg_set (frchainP->frch_seg, frchainP->frch_subseg);
1407 /* This now gets called even if we had errors. In that case,
1408 any alignment is meaningless, and, moreover, will look weird
1409 if we are generating a listing. */
1410 if (!had_errors ())
1411 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1413 if (subseg_text_p (now_seg))
1414 frag_align_code (alignment, 0);
1415 else
1416 frag_align (alignment, 0, 0);
1418 /* frag_align will have left a new frag.
1419 Use this last frag for an empty ".fill".
1421 For this segment ...
1422 Create a last frag. Do not leave a "being filled in frag". */
1423 frag_wane (frag_now);
1424 frag_now->fr_fix = 0;
1425 know (frag_now->fr_next == NULL);
1429 /* Write the object file. */
1431 void
1432 write_object_file ()
1434 #if ! defined (BFD_ASSEMBLER) || ! defined (WORKING_DOT_WORD)
1435 fragS *fragP; /* Track along all frags. */
1436 #endif
1438 /* Do we really want to write it? */
1440 int n_warns, n_errs;
1441 n_warns = had_warnings ();
1442 n_errs = had_errors ();
1443 /* The -Z flag indicates that an object file should be generated,
1444 regardless of warnings and errors. */
1445 if (flag_always_generate_output)
1447 if (n_warns || n_errs)
1448 as_warn (_("%d error%s, %d warning%s, generating bad object file"),
1449 n_errs, n_errs == 1 ? "" : "s",
1450 n_warns, n_warns == 1 ? "" : "s");
1452 else
1454 if (n_errs)
1455 as_fatal (_("%d error%s, %d warning%s, no object file generated"),
1456 n_errs, n_errs == 1 ? "" : "s",
1457 n_warns, n_warns == 1 ? "" : "s");
1461 #ifdef OBJ_VMS
1462 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1463 a routine to check for the definition of the procedure "_main",
1464 and if so -- fix it up so that it can be program entry point. */
1465 vms_check_for_main ();
1466 #endif /* OBJ_VMS */
1468 /* From now on, we don't care about sub-segments. Build one frag chain
1469 for each segment. Linked thru fr_next. */
1471 #ifdef BFD_ASSEMBLER
1472 /* Remove the sections created by gas for its own purposes. */
1474 asection **seclist;
1475 int i;
1477 seclist = &stdoutput->sections;
1478 while (*seclist)
1480 if (*seclist == reg_section || *seclist == expr_section)
1482 bfd_section_list_remove (stdoutput, seclist);
1483 stdoutput->section_count--;
1485 else
1486 seclist = &(*seclist)->next;
1488 i = 0;
1489 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1492 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1493 #else
1494 remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
1495 remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
1496 remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
1497 #endif
1499 /* We have two segments. If user gave -R flag, then we must put the
1500 data frags into the text segment. Do this before relaxing so
1501 we know to take advantage of -R and make shorter addresses. */
1502 #if !defined (OBJ_AOUT) || defined (BFD_ASSEMBLER)
1503 if (flag_readonly_data_in_text)
1505 merge_data_into_text ();
1507 #endif
1509 #ifdef BFD_ASSEMBLER
1510 while (1)
1512 int changed;
1514 #ifndef WORKING_DOT_WORD
1515 /* We need to reset the markers in the broken word list and
1516 associated frags between calls to relax_segment (via
1517 relax_seg). Since the broken word list is global, we do it
1518 once per round, rather than locally in relax_segment for each
1519 segment. */
1520 struct broken_word *brokp;
1522 for (brokp = broken_words;
1523 brokp != (struct broken_word *) NULL;
1524 brokp = brokp->next_broken_word)
1526 brokp->added = 0;
1528 if (brokp->dispfrag != (fragS *) NULL
1529 && brokp->dispfrag->fr_type == rs_broken_word)
1530 brokp->dispfrag->fr_subtype = 0;
1532 #endif
1534 changed = 0;
1535 bfd_map_over_sections (stdoutput, relax_seg, &changed);
1536 if (!changed)
1537 break;
1540 /* Note - Most ports will use the default value of
1541 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
1542 local symbols to be resolved, removing their frag information.
1543 Some ports however, will not have finished relaxing all of
1544 their frags and will still need the local symbol frag
1545 information. These ports can set
1546 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
1547 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
1549 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
1550 #else
1551 relax_and_size_all_segments ();
1552 #endif /* BFD_ASSEMBLER */
1554 /* Relaxation has completed. Freeze all syms. */
1555 finalize_syms = 1;
1557 #ifndef BFD_ASSEMBLER
1558 /* Crawl the symbol chain.
1560 For each symbol whose value depends on a frag, take the address of
1561 that frag and subsume it into the value of the symbol.
1562 After this, there is just one way to lookup a symbol value.
1563 Values are left in their final state for object file emission.
1564 We adjust the values of 'L' local symbols, even if we do
1565 not intend to emit them to the object file, because their values
1566 are needed for fix-ups.
1568 Unless we saw a -L flag, remove all symbols that begin with 'L'
1569 from the symbol chain. (They are still pointed to by the fixes.)
1571 Count the remaining symbols.
1572 Assign a symbol number to each symbol.
1573 Count the number of string-table chars we will emit.
1574 Put this info into the headers as appropriate. */
1575 know (zero_address_frag.fr_address == 0);
1576 string_byte_count = sizeof (string_byte_count);
1578 obj_crawl_symbol_chain (&headers);
1580 if (string_byte_count == sizeof (string_byte_count))
1581 string_byte_count = 0;
1583 H_SET_STRING_SIZE (&headers, string_byte_count);
1585 /* Addresses of frags now reflect addresses we use in the object file.
1586 Symbol values are correct.
1587 Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
1588 Also converting any machine-dependent frags using md_convert_frag(); */
1589 subseg_change (SEG_TEXT, 0);
1591 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1593 /* At this point we have linked all the frags into a single
1594 chain. However, cvt_frag_to_fill may call md_convert_frag
1595 which may call fix_new. We need to ensure that fix_new adds
1596 the fixup to the right section. */
1597 if (fragP == data_frag_root)
1598 subseg_change (SEG_DATA, 0);
1600 cvt_frag_to_fill (&headers, SEG_TEXT, fragP);
1602 /* Some assert macros don't work with # directives mixed in. */
1603 #ifndef NDEBUG
1604 if (!(fragP->fr_next == NULL
1605 #ifdef OBJ_BOUT
1606 || fragP->fr_next == data_frag_root
1607 #endif
1608 || ((fragP->fr_next->fr_address - fragP->fr_address)
1609 == (fragP->fr_fix + fragP->fr_offset * fragP->fr_var))))
1610 abort ();
1611 #endif
1613 #endif /* ! BFD_ASSEMBLER */
1615 #ifndef WORKING_DOT_WORD
1617 struct broken_word *lie;
1618 struct broken_word **prevP;
1620 prevP = &broken_words;
1621 for (lie = broken_words; lie; lie = lie->next_broken_word)
1622 if (!lie->added)
1624 expressionS exp;
1626 subseg_change (lie->seg, lie->subseg);
1627 exp.X_op = O_subtract;
1628 exp.X_add_symbol = lie->add;
1629 exp.X_op_symbol = lie->sub;
1630 exp.X_add_number = lie->addnum;
1631 #ifdef BFD_ASSEMBLER
1632 #ifdef TC_CONS_FIX_NEW
1633 TC_CONS_FIX_NEW (lie->frag,
1634 lie->word_goes_here - lie->frag->fr_literal,
1635 2, &exp);
1636 #else
1637 fix_new_exp (lie->frag,
1638 lie->word_goes_here - lie->frag->fr_literal,
1639 2, &exp, 0, BFD_RELOC_16);
1640 #endif
1641 #else
1642 #if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
1643 fix_new_exp (lie->frag,
1644 lie->word_goes_here - lie->frag->fr_literal,
1645 2, &exp, 0, NO_RELOC);
1646 #else
1647 #ifdef TC_NS32K
1648 fix_new_ns32k_exp (lie->frag,
1649 lie->word_goes_here - lie->frag->fr_literal,
1650 2, &exp, 0, 0, 2, 0, 0);
1651 #else
1652 fix_new_exp (lie->frag,
1653 lie->word_goes_here - lie->frag->fr_literal,
1654 2, &exp, 0, 0);
1655 #endif /* TC_NS32K */
1656 #endif /* TC_SPARC|TC_A29K|NEED_FX_R_TYPE */
1657 #endif /* BFD_ASSEMBLER */
1658 *prevP = lie->next_broken_word;
1660 else
1661 prevP = &(lie->next_broken_word);
1663 for (lie = broken_words; lie;)
1665 struct broken_word *untruth;
1666 char *table_ptr;
1667 addressT table_addr;
1668 addressT from_addr, to_addr;
1669 int n, m;
1671 subseg_change (lie->seg, lie->subseg);
1672 fragP = lie->dispfrag;
1674 /* Find out how many broken_words go here. */
1675 n = 0;
1676 for (untruth = lie;
1677 untruth && untruth->dispfrag == fragP;
1678 untruth = untruth->next_broken_word)
1679 if (untruth->added == 1)
1680 n++;
1682 table_ptr = lie->dispfrag->fr_opcode;
1683 table_addr = (lie->dispfrag->fr_address
1684 + (table_ptr - lie->dispfrag->fr_literal));
1685 /* Create the jump around the long jumps. This is a short
1686 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1687 from_addr = table_addr;
1688 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1689 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1690 lie->add);
1691 table_ptr += md_short_jump_size;
1692 table_addr += md_short_jump_size;
1694 for (m = 0;
1695 lie && lie->dispfrag == fragP;
1696 m++, lie = lie->next_broken_word)
1698 if (lie->added == 2)
1699 continue;
1700 /* Patch the jump table. */
1701 /* This is the offset from ??? to table_ptr+0. */
1702 to_addr = table_addr - S_GET_VALUE (lie->sub);
1703 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1704 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_addr, lie);
1705 #endif
1706 md_number_to_chars (lie->word_goes_here, to_addr, 2);
1707 for (untruth = lie->next_broken_word;
1708 untruth && untruth->dispfrag == fragP;
1709 untruth = untruth->next_broken_word)
1711 if (untruth->use_jump == lie)
1712 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
1715 /* Install the long jump. */
1716 /* This is a long jump from table_ptr+0 to the final target. */
1717 from_addr = table_addr;
1718 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1719 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1720 lie->add);
1721 table_ptr += md_long_jump_size;
1722 table_addr += md_long_jump_size;
1726 #endif /* not WORKING_DOT_WORD */
1728 #ifndef BFD_ASSEMBLER
1729 #ifndef OBJ_VMS
1730 { /* not vms */
1731 char *the_object_file;
1732 long object_file_size;
1733 /* Scan every FixS performing fixups. We had to wait until now to
1734 do this because md_convert_frag() may have made some fixSs. */
1735 int trsize, drsize;
1737 subseg_change (SEG_TEXT, 0);
1738 trsize = md_reloc_size * fixup_segment (text_fix_root, SEG_TEXT);
1739 subseg_change (SEG_DATA, 0);
1740 drsize = md_reloc_size * fixup_segment (data_fix_root, SEG_DATA);
1741 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
1743 /* FIXME: Move this stuff into the pre-write-hook. */
1744 H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
1745 H_SET_ENTRY_POINT (&headers, 0);
1747 obj_pre_write_hook (&headers); /* Extra coff stuff. */
1749 object_file_size = H_GET_FILE_SIZE (&headers);
1750 next_object_file_charP = the_object_file = xmalloc (object_file_size);
1752 output_file_create (out_file_name);
1754 obj_header_append (&next_object_file_charP, &headers);
1756 know ((next_object_file_charP - the_object_file)
1757 == H_GET_HEADER_SIZE (&headers));
1759 /* Emit code. */
1760 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1762 register long count;
1763 register char *fill_literal;
1764 register long fill_size;
1766 PROGRESS (1);
1767 know (fragP->fr_type == rs_fill);
1768 append (&next_object_file_charP, fragP->fr_literal,
1769 (unsigned long) fragP->fr_fix);
1770 fill_literal = fragP->fr_literal + fragP->fr_fix;
1771 fill_size = fragP->fr_var;
1772 know (fragP->fr_offset >= 0);
1774 for (count = fragP->fr_offset; count; count--)
1775 append (&next_object_file_charP, fill_literal,
1776 (unsigned long) fill_size);
1779 know ((next_object_file_charP - the_object_file)
1780 == (H_GET_HEADER_SIZE (&headers)
1781 + H_GET_TEXT_SIZE (&headers)
1782 + H_GET_DATA_SIZE (&headers)));
1784 /* Emit relocations. */
1785 obj_emit_relocations (&next_object_file_charP, text_fix_root,
1786 (relax_addressT) 0);
1787 know ((next_object_file_charP - the_object_file)
1788 == (H_GET_HEADER_SIZE (&headers)
1789 + H_GET_TEXT_SIZE (&headers)
1790 + H_GET_DATA_SIZE (&headers)
1791 + H_GET_TEXT_RELOCATION_SIZE (&headers)));
1792 #ifdef TC_I960
1793 /* Make addresses in data relocation directives relative to beginning of
1794 first data fragment, not end of last text fragment: alignment of the
1795 start of the data segment may place a gap between the segments. */
1796 obj_emit_relocations (&next_object_file_charP, data_fix_root,
1797 data0_frchainP->frch_root->fr_address);
1798 #else /* TC_I960 */
1799 obj_emit_relocations (&next_object_file_charP, data_fix_root,
1800 text_last_frag->fr_address);
1801 #endif /* TC_I960 */
1803 know ((next_object_file_charP - the_object_file)
1804 == (H_GET_HEADER_SIZE (&headers)
1805 + H_GET_TEXT_SIZE (&headers)
1806 + H_GET_DATA_SIZE (&headers)
1807 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1808 + H_GET_DATA_RELOCATION_SIZE (&headers)));
1810 /* Emit line number entries. */
1811 OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
1812 know ((next_object_file_charP - the_object_file)
1813 == (H_GET_HEADER_SIZE (&headers)
1814 + H_GET_TEXT_SIZE (&headers)
1815 + H_GET_DATA_SIZE (&headers)
1816 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1817 + H_GET_DATA_RELOCATION_SIZE (&headers)
1818 + H_GET_LINENO_SIZE (&headers)));
1820 /* Emit symbols. */
1821 obj_emit_symbols (&next_object_file_charP, symbol_rootP);
1822 know ((next_object_file_charP - the_object_file)
1823 == (H_GET_HEADER_SIZE (&headers)
1824 + H_GET_TEXT_SIZE (&headers)
1825 + H_GET_DATA_SIZE (&headers)
1826 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1827 + H_GET_DATA_RELOCATION_SIZE (&headers)
1828 + H_GET_LINENO_SIZE (&headers)
1829 + H_GET_SYMBOL_TABLE_SIZE (&headers)));
1831 /* Emit strings. */
1832 if (string_byte_count > 0)
1833 obj_emit_strings (&next_object_file_charP);
1835 #ifdef BFD_HEADERS
1836 bfd_seek (stdoutput, (file_ptr) 0, 0);
1837 bfd_bwrite (the_object_file, (bfd_size_type) object_file_size, stdoutput);
1838 #else
1840 /* Write the data to the file. */
1841 output_file_append (the_object_file, object_file_size, out_file_name);
1842 free (the_object_file);
1843 #endif
1845 #else /* OBJ_VMS */
1846 /* Now do the VMS-dependent part of writing the object file. */
1847 vms_write_object_file (H_GET_TEXT_SIZE (&headers),
1848 H_GET_DATA_SIZE (&headers),
1849 H_GET_BSS_SIZE (&headers),
1850 text_frag_root, data_frag_root);
1851 #endif /* OBJ_VMS */
1852 #else /* BFD_ASSEMBLER */
1854 /* Resolve symbol values. This needs to be done before processing
1855 the relocations. */
1856 if (symbol_rootP)
1858 symbolS *symp;
1860 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1861 resolve_symbol_value (symp);
1863 resolve_local_symbol_values ();
1865 PROGRESS (1);
1867 #ifdef tc_frob_file_before_adjust
1868 tc_frob_file_before_adjust ();
1869 #endif
1870 #ifdef obj_frob_file_before_adjust
1871 obj_frob_file_before_adjust ();
1872 #endif
1874 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
1876 #ifdef tc_frob_file_before_fix
1877 tc_frob_file_before_fix ();
1878 #endif
1879 #ifdef obj_frob_file_before_fix
1880 obj_frob_file_before_fix ();
1881 #endif
1883 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
1885 /* Set up symbol table, and write it out. */
1886 if (symbol_rootP)
1888 symbolS *symp;
1890 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1892 int punt = 0;
1893 const char *name;
1895 if (symbol_mri_common_p (symp))
1897 if (S_IS_EXTERNAL (symp))
1898 as_bad (_("%s: global symbols not supported in common sections"),
1899 S_GET_NAME (symp));
1900 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1901 continue;
1904 name = S_GET_NAME (symp);
1905 if (name)
1907 const char *name2 =
1908 decode_local_label_name ((char *) S_GET_NAME (symp));
1909 /* They only differ if `name' is a fb or dollar local
1910 label name. */
1911 if (name2 != name && ! S_IS_DEFINED (symp))
1912 as_bad (_("local label `%s' is not defined"), name2);
1915 /* Do it again, because adjust_reloc_syms might introduce
1916 more symbols. They'll probably only be section symbols,
1917 but they'll still need to have the values computed. */
1918 resolve_symbol_value (symp);
1920 /* Skip symbols which were equated to undefined or common
1921 symbols. */
1922 if (symbol_equated_reloc_p (symp))
1924 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1925 continue;
1928 /* So far, common symbols have been treated like undefined symbols.
1929 Put them in the common section now. */
1930 if (S_IS_DEFINED (symp) == 0
1931 && S_GET_VALUE (symp) != 0)
1932 S_SET_SEGMENT (symp, bfd_com_section_ptr);
1933 #if 0
1934 printf ("symbol `%s'\n\t@%x: value=%d flags=%x seg=%s\n",
1935 S_GET_NAME (symp), symp,
1936 S_GET_VALUE (symp),
1937 symbol_get_bfdsym (symp)->flags,
1938 segment_name (S_GET_SEGMENT (symp)));
1939 #endif
1941 #ifdef obj_frob_symbol
1942 obj_frob_symbol (symp, punt);
1943 #endif
1944 #ifdef tc_frob_symbol
1945 if (! punt || symbol_used_in_reloc_p (symp))
1946 tc_frob_symbol (symp, punt);
1947 #endif
1949 /* If we don't want to keep this symbol, splice it out of
1950 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1951 want section symbols. Otherwise, we skip local symbols
1952 and symbols that the frob_symbol macros told us to punt,
1953 but we keep such symbols if they are used in relocs. */
1954 if (symp == abs_section_sym
1955 || (! EMIT_SECTION_SYMBOLS
1956 && symbol_section_p (symp))
1957 /* Note that S_IS_EXTERN and S_IS_LOCAL are not always
1958 opposites. Sometimes the former checks flags and the
1959 latter examines the name... */
1960 || (!S_IS_EXTERN (symp)
1961 && (punt || S_IS_LOCAL (symp))
1962 && ! symbol_used_in_reloc_p (symp)))
1964 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1966 /* After symbol_remove, symbol_next(symp) still returns
1967 the one that came after it in the chain. So we don't
1968 need to do any extra cleanup work here. */
1969 continue;
1972 /* Make sure we really got a value for the symbol. */
1973 if (! symbol_resolved_p (symp))
1975 as_bad (_("can't resolve value for symbol `%s'"),
1976 S_GET_NAME (symp));
1977 symbol_mark_resolved (symp);
1980 /* Set the value into the BFD symbol. Up til now the value
1981 has only been kept in the gas symbolS struct. */
1982 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1986 PROGRESS (1);
1988 /* Now do any format-specific adjustments to the symbol table, such
1989 as adding file symbols. */
1990 #ifdef tc_adjust_symtab
1991 tc_adjust_symtab ();
1992 #endif
1993 #ifdef obj_adjust_symtab
1994 obj_adjust_symtab ();
1995 #endif
1997 /* Now that all the sizes are known, and contents correct, we can
1998 start writing to the file. */
1999 set_symtab ();
2001 /* If *_frob_file changes the symbol value at this point, it is
2002 responsible for moving the changed value into symp->bsym->value
2003 as well. Hopefully all symbol value changing can be done in
2004 *_frob_symbol. */
2005 #ifdef tc_frob_file
2006 tc_frob_file ();
2007 #endif
2008 #ifdef obj_frob_file
2009 obj_frob_file ();
2010 #endif
2012 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
2014 #ifdef tc_frob_file_after_relocs
2015 tc_frob_file_after_relocs ();
2016 #endif
2017 #ifdef obj_frob_file_after_relocs
2018 obj_frob_file_after_relocs ();
2019 #endif
2021 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
2022 #endif /* BFD_ASSEMBLER */
2024 #endif /* ! BFD */
2026 #ifdef TC_GENERIC_RELAX_TABLE
2028 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2030 long
2031 relax_frag (segment, fragP, stretch)
2032 segT segment;
2033 fragS *fragP;
2034 long stretch;
2036 const relax_typeS *this_type;
2037 const relax_typeS *start_type;
2038 relax_substateT next_state;
2039 relax_substateT this_state;
2040 long growth;
2041 offsetT aim;
2042 addressT target;
2043 addressT address;
2044 symbolS *symbolP;
2045 const relax_typeS *table;
2047 target = fragP->fr_offset;
2048 address = fragP->fr_address;
2049 table = TC_GENERIC_RELAX_TABLE;
2050 this_state = fragP->fr_subtype;
2051 start_type = this_type = table + this_state;
2052 symbolP = fragP->fr_symbol;
2054 if (symbolP)
2056 fragS *sym_frag;
2058 sym_frag = symbol_get_frag (symbolP);
2060 #ifndef DIFF_EXPR_OK
2061 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2062 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2063 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2064 || (S_GET_SEGMENT (symbolP) == SEG_BSS)
2065 || (S_GET_SEGMENT (symbolP) == SEG_TEXT));
2066 #endif
2067 know (sym_frag != NULL);
2068 #endif
2069 know (S_GET_SEGMENT (symbolP) != absolute_section
2070 || sym_frag == &zero_address_frag);
2071 target += S_GET_VALUE (symbolP);
2073 /* If frag has yet to be reached on this pass,
2074 assume it will move by STRETCH just as we did.
2075 If this is not so, it will be because some frag
2076 between grows, and that will force another pass. */
2078 if (stretch != 0
2079 && sym_frag->relax_marker != fragP->relax_marker
2080 && S_GET_SEGMENT (symbolP) == segment)
2082 target += stretch;
2086 aim = target - address - fragP->fr_fix;
2087 #ifdef TC_PCREL_ADJUST
2088 /* Currently only the ns32k family needs this. */
2089 aim += TC_PCREL_ADJUST (fragP);
2090 /* #else */
2091 /* This machine doesn't want to use pcrel_adjust.
2092 In that case, pcrel_adjust should be zero. */
2093 #if 0
2094 assert (fragP->fr_targ.ns32k.pcrel_adjust == 0);
2095 #endif
2096 #endif
2097 #ifdef md_prepare_relax_scan /* formerly called M68K_AIM_KLUDGE */
2098 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2099 #endif
2101 if (aim < 0)
2103 /* Look backwards. */
2104 for (next_state = this_type->rlx_more; next_state;)
2105 if (aim >= this_type->rlx_backward)
2106 next_state = 0;
2107 else
2109 /* Grow to next state. */
2110 this_state = next_state;
2111 this_type = table + this_state;
2112 next_state = this_type->rlx_more;
2115 else
2117 /* Look forwards. */
2118 for (next_state = this_type->rlx_more; next_state;)
2119 if (aim <= this_type->rlx_forward)
2120 next_state = 0;
2121 else
2123 /* Grow to next state. */
2124 this_state = next_state;
2125 this_type = table + this_state;
2126 next_state = this_type->rlx_more;
2130 growth = this_type->rlx_length - start_type->rlx_length;
2131 if (growth != 0)
2132 fragP->fr_subtype = this_state;
2133 return growth;
2136 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2138 /* Relax_align. Advance location counter to next address that has 'alignment'
2139 lowest order bits all 0s, return size of adjustment made. */
2140 static relax_addressT
2141 relax_align (address, alignment)
2142 register relax_addressT address; /* Address now. */
2143 register int alignment; /* Alignment (binary). */
2145 relax_addressT mask;
2146 relax_addressT new_address;
2148 mask = ~((~0) << alignment);
2149 new_address = (address + mask) & (~mask);
2150 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2151 if (linkrelax)
2152 /* We must provide lots of padding, so the linker can discard it
2153 when needed. The linker will not add extra space, ever. */
2154 new_address += (1 << alignment);
2155 #endif
2156 return (new_address - address);
2159 /* Now we have a segment, not a crowd of sub-segments, we can make
2160 fr_address values.
2162 Relax the frags.
2164 After this, all frags in this segment have addresses that are correct
2165 within the segment. Since segments live in different file addresses,
2166 these frag addresses may not be the same as final object-file
2167 addresses. */
2170 relax_segment (segment_frag_root, segment)
2171 struct frag *segment_frag_root;
2172 segT segment;
2174 register struct frag *fragP;
2175 register relax_addressT address;
2176 int ret;
2178 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2179 know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
2180 #endif
2181 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2182 subseg_change (segment, 0);
2184 /* For each frag in segment: count and store (a 1st guess of)
2185 fr_address. */
2186 address = 0;
2187 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2189 fragP->relax_marker = 0;
2190 fragP->fr_address = address;
2191 address += fragP->fr_fix;
2193 switch (fragP->fr_type)
2195 case rs_fill:
2196 address += fragP->fr_offset * fragP->fr_var;
2197 break;
2199 case rs_align:
2200 case rs_align_code:
2201 case rs_align_test:
2203 addressT offset = relax_align (address, (int) fragP->fr_offset);
2205 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2206 offset = 0;
2208 if (offset % fragP->fr_var != 0)
2210 as_bad_where (fragP->fr_file, fragP->fr_line,
2211 _("alignment padding (%lu bytes) not a multiple of %ld"),
2212 (unsigned long) offset, (long) fragP->fr_var);
2213 offset -= (offset % fragP->fr_var);
2216 address += offset;
2218 break;
2220 case rs_org:
2221 case rs_space:
2222 /* Assume .org is nugatory. It will grow with 1st relax. */
2223 break;
2225 case rs_machine_dependent:
2226 /* If fr_symbol is an expression, this call to
2227 resolve_symbol_value sets up the correct segment, which will
2228 likely be needed in md_estimate_size_before_relax. */
2229 if (fragP->fr_symbol)
2230 resolve_symbol_value (fragP->fr_symbol);
2232 address += md_estimate_size_before_relax (fragP, segment);
2233 break;
2235 #ifndef WORKING_DOT_WORD
2236 /* Broken words don't concern us yet. */
2237 case rs_broken_word:
2238 break;
2239 #endif
2241 case rs_leb128:
2242 /* Initial guess is always 1; doing otherwise can result in
2243 stable solutions that are larger than the minimum. */
2244 address += fragP->fr_offset = 1;
2245 break;
2247 case rs_cfa:
2248 address += eh_frame_estimate_size_before_relax (fragP);
2249 break;
2251 case rs_dwarf2dbg:
2252 address += dwarf2dbg_estimate_size_before_relax (fragP);
2253 break;
2255 default:
2256 BAD_CASE (fragP->fr_type);
2257 break;
2261 /* Do relax(). */
2263 long stretch; /* May be any size, 0 or negative. */
2264 /* Cumulative number of addresses we have relaxed this pass.
2265 We may have relaxed more than one address. */
2266 int stretched; /* Have we stretched on this pass? */
2267 /* This is 'cuz stretch may be zero, when, in fact some piece of code
2268 grew, and another shrank. If a branch instruction doesn't fit anymore,
2269 we could be scrod. */
2273 stretch = 0;
2274 stretched = 0;
2276 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2278 long growth = 0;
2279 addressT was_address;
2280 offsetT offset;
2281 symbolS *symbolP;
2283 fragP->relax_marker ^= 1;
2284 was_address = fragP->fr_address;
2285 address = fragP->fr_address += stretch;
2286 symbolP = fragP->fr_symbol;
2287 offset = fragP->fr_offset;
2289 switch (fragP->fr_type)
2291 case rs_fill: /* .fill never relaxes. */
2292 growth = 0;
2293 break;
2295 #ifndef WORKING_DOT_WORD
2296 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2297 for it I do not want to write it. I do not want to have
2298 anything to do with it. This is not the proper way to
2299 implement this misfeature. */
2300 case rs_broken_word:
2302 struct broken_word *lie;
2303 struct broken_word *untruth;
2305 /* Yes this is ugly (storing the broken_word pointer
2306 in the symbol slot). Still, this whole chunk of
2307 code is ugly, and I don't feel like doing anything
2308 about it. Think of it as stubbornness in action. */
2309 growth = 0;
2310 for (lie = (struct broken_word *) (fragP->fr_symbol);
2311 lie && lie->dispfrag == fragP;
2312 lie = lie->next_broken_word)
2315 if (lie->added)
2316 continue;
2318 offset = (S_GET_VALUE (lie->add)
2319 + lie->addnum
2320 - S_GET_VALUE (lie->sub));
2321 if (offset <= -32768 || offset >= 32767)
2323 if (flag_warn_displacement)
2325 char buf[50];
2326 sprint_value (buf, (addressT) lie->addnum);
2327 as_warn_where (fragP->fr_file, fragP->fr_line,
2328 _(".word %s-%s+%s didn't fit"),
2329 S_GET_NAME (lie->add),
2330 S_GET_NAME (lie->sub),
2331 buf);
2333 lie->added = 1;
2334 if (fragP->fr_subtype == 0)
2336 fragP->fr_subtype++;
2337 growth += md_short_jump_size;
2339 for (untruth = lie->next_broken_word;
2340 untruth && untruth->dispfrag == lie->dispfrag;
2341 untruth = untruth->next_broken_word)
2342 if ((symbol_get_frag (untruth->add)
2343 == symbol_get_frag (lie->add))
2344 && (S_GET_VALUE (untruth->add)
2345 == S_GET_VALUE (lie->add)))
2347 untruth->added = 2;
2348 untruth->use_jump = lie;
2350 growth += md_long_jump_size;
2354 break;
2355 } /* case rs_broken_word */
2356 #endif
2357 case rs_align:
2358 case rs_align_code:
2359 case rs_align_test:
2361 addressT oldoff, newoff;
2363 oldoff = relax_align (was_address + fragP->fr_fix,
2364 (int) offset);
2365 newoff = relax_align (address + fragP->fr_fix,
2366 (int) offset);
2368 if (fragP->fr_subtype != 0)
2370 if (oldoff > fragP->fr_subtype)
2371 oldoff = 0;
2372 if (newoff > fragP->fr_subtype)
2373 newoff = 0;
2376 growth = newoff - oldoff;
2378 break;
2380 case rs_org:
2382 addressT target = offset;
2383 addressT after;
2385 if (symbolP)
2387 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2388 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2389 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2390 || (S_GET_SEGMENT (symbolP) == SEG_TEXT)
2391 || S_GET_SEGMENT (symbolP) == SEG_BSS);
2392 know (symbolP->sy_frag);
2393 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2394 || (symbolP->sy_frag == &zero_address_frag));
2395 #endif
2396 /* Convert from an actual address to an octet offset
2397 into the section. Here it is assumed that the
2398 section's VMA is zero, and can omit subtracting it
2399 from the symbol's value to get the address offset. */
2400 know (S_GET_SECTION (symbolP)->vma == 0);
2401 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2404 know (fragP->fr_next);
2405 after = fragP->fr_next->fr_address;
2406 growth = target - after;
2407 if (growth < 0)
2409 /* Growth may be negative, but variable part of frag
2410 cannot have fewer than 0 chars. That is, we can't
2411 .org backwards. */
2412 as_bad_where (fragP->fr_file, fragP->fr_line,
2413 _("attempt to .org backwards"));
2415 /* We've issued an error message. Change the
2416 frag to avoid cascading errors. */
2417 fragP->fr_type = rs_align;
2418 fragP->fr_subtype = 0;
2419 fragP->fr_offset = 0;
2420 fragP->fr_fix = after - address;
2421 growth = stretch;
2424 /* This is an absolute growth factor */
2425 growth -= stretch;
2426 break;
2429 case rs_space:
2430 growth = 0;
2431 if (symbolP)
2433 offsetT amount;
2435 amount = S_GET_VALUE (symbolP);
2436 if (S_GET_SEGMENT (symbolP) != absolute_section
2437 || S_IS_COMMON (symbolP)
2438 || ! S_IS_DEFINED (symbolP))
2440 as_bad_where (fragP->fr_file, fragP->fr_line,
2441 _(".space specifies non-absolute value"));
2442 /* Prevent repeat of this error message. */
2443 fragP->fr_symbol = 0;
2445 else if (amount < 0)
2447 as_warn_where (fragP->fr_file, fragP->fr_line,
2448 _(".space or .fill with negative value, ignored"));
2449 fragP->fr_symbol = 0;
2451 else
2452 growth = (was_address + fragP->fr_fix + amount
2453 - fragP->fr_next->fr_address);
2455 break;
2457 case rs_machine_dependent:
2458 #ifdef md_relax_frag
2459 growth = md_relax_frag (segment, fragP, stretch);
2460 #else
2461 #ifdef TC_GENERIC_RELAX_TABLE
2462 /* The default way to relax a frag is to look through
2463 TC_GENERIC_RELAX_TABLE. */
2464 growth = relax_frag (segment, fragP, stretch);
2465 #endif /* TC_GENERIC_RELAX_TABLE */
2466 #endif
2467 break;
2469 case rs_leb128:
2471 valueT value;
2472 int size;
2474 value = resolve_symbol_value (fragP->fr_symbol);
2475 size = sizeof_leb128 (value, fragP->fr_subtype);
2476 growth = size - fragP->fr_offset;
2477 fragP->fr_offset = size;
2479 break;
2481 case rs_cfa:
2482 growth = eh_frame_relax_frag (fragP);
2483 break;
2485 case rs_dwarf2dbg:
2486 growth = dwarf2dbg_relax_frag (fragP);
2487 break;
2489 default:
2490 BAD_CASE (fragP->fr_type);
2491 break;
2493 if (growth)
2495 stretch += growth;
2496 stretched = 1;
2498 } /* For each frag in the segment. */
2500 while (stretched); /* Until nothing further to relax. */
2501 } /* do_relax */
2503 ret = 0;
2504 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2505 if (fragP->last_fr_address != fragP->fr_address)
2507 fragP->last_fr_address = fragP->fr_address;
2508 ret = 1;
2510 return ret;
2513 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
2515 /* fixup_segment()
2517 Go through all the fixS's in a segment and see which ones can be
2518 handled now. (These consist of fixS where we have since discovered
2519 the value of a symbol, or the address of the frag involved.)
2520 For each one, call md_apply_fix3 to put the fix into the frag data.
2522 Result is a count of how many relocation structs will be needed to
2523 handle the remaining fixS's that we couldn't completely handle here.
2524 These will be output later by emit_relocations(). */
2526 static long
2527 fixup_segment (fixP, this_segment)
2528 fixS *fixP;
2529 segT this_segment;
2531 long seg_reloc_count = 0;
2532 valueT add_number;
2533 fragS *fragP;
2534 segT add_symbol_segment = absolute_section;
2536 if (fixP != NULL && abs_section_sym == NULL)
2538 #ifndef BFD_ASSEMBLER
2539 abs_section_sym = &abs_symbol;
2540 #else
2541 abs_section_sym = section_symbol (absolute_section);
2542 #endif
2545 /* If the linker is doing the relaxing, we must not do any fixups.
2547 Well, strictly speaking that's not true -- we could do any that
2548 are PC-relative and don't cross regions that could change size.
2549 And for the i960 we might be able to turn callx/callj into bal
2550 anyways in cases where we know the maximum displacement. */
2551 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
2553 for (; fixP; fixP = fixP->fx_next)
2554 if (!fixP->fx_done)
2556 if (fixP->fx_addsy == NULL)
2558 /* There was no symbol required by this relocation.
2559 However, BFD doesn't really handle relocations
2560 without symbols well. So fake up a local symbol in
2561 the absolute section. */
2562 fixP->fx_addsy = abs_section_sym;
2564 symbol_mark_used_in_reloc (fixP->fx_addsy);
2565 if (fixP->fx_subsy != NULL)
2566 symbol_mark_used_in_reloc (fixP->fx_subsy);
2567 seg_reloc_count++;
2569 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2570 return seg_reloc_count;
2573 for (; fixP; fixP = fixP->fx_next)
2575 #ifdef DEBUG5
2576 fprintf (stderr, "\nprocessing fixup:\n");
2577 print_fixup (fixP);
2578 #endif
2580 fragP = fixP->fx_frag;
2581 know (fragP);
2582 #ifdef TC_VALIDATE_FIX
2583 TC_VALIDATE_FIX (fixP, this_segment, skip);
2584 #endif
2585 add_number = fixP->fx_offset;
2587 if (fixP->fx_addsy != NULL
2588 && symbol_mri_common_p (fixP->fx_addsy))
2590 know (fixP->fx_addsy->sy_value.X_op == O_symbol);
2591 add_number += S_GET_VALUE (fixP->fx_addsy);
2592 fixP->fx_offset = add_number;
2593 fixP->fx_addsy
2594 = symbol_get_value_expression (fixP->fx_addsy)->X_add_symbol;
2597 if (fixP->fx_addsy != NULL)
2598 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
2600 if (fixP->fx_subsy != NULL)
2602 segT sub_symbol_segment;
2603 resolve_symbol_value (fixP->fx_subsy);
2604 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
2605 if (fixP->fx_addsy != NULL
2606 && sub_symbol_segment == add_symbol_segment
2607 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
2609 add_number += S_GET_VALUE (fixP->fx_addsy);
2610 add_number -= S_GET_VALUE (fixP->fx_subsy);
2611 fixP->fx_offset = add_number;
2612 /* If the back-end code has selected a pc-relative
2613 reloc, adjust the value to be pc-relative. */
2614 if (1
2615 #ifdef TC_M68K
2616 /* See the comment below about 68k weirdness. */
2617 && 0
2618 #endif
2619 && fixP->fx_pcrel)
2620 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
2621 fixP->fx_addsy = NULL;
2622 fixP->fx_subsy = NULL;
2623 fixP->fx_pcrel = 0;
2625 else if (sub_symbol_segment == absolute_section
2626 && !TC_FORCE_RELOCATION_SUB_ABS (fixP))
2628 add_number -= S_GET_VALUE (fixP->fx_subsy);
2629 fixP->fx_offset = add_number;
2630 fixP->fx_subsy = NULL;
2632 else if (sub_symbol_segment == this_segment
2633 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP))
2635 add_number -= S_GET_VALUE (fixP->fx_subsy);
2636 fixP->fx_offset = (add_number + fixP->fx_dot_value
2637 + fixP->fx_frag->fr_address);
2639 /* Make it pc-relative. If the back-end code has not
2640 selected a pc-relative reloc, cancel the adjustment
2641 we do later on all pc-relative relocs. */
2642 if (0
2643 #ifdef TC_M68K
2644 /* Do this for m68k even if it's already described
2645 as pc-relative. On the m68k, an operand of
2646 "pc@(foo-.-2)" should address "foo" in a
2647 pc-relative mode. */
2648 || 1
2649 #endif
2650 || !fixP->fx_pcrel)
2651 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
2652 fixP->fx_subsy = NULL;
2653 fixP->fx_pcrel = 1;
2655 else if (!TC_VALIDATE_FIX_SUB (fixP))
2657 as_bad_where (fixP->fx_file, fixP->fx_line,
2658 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
2659 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
2660 segment_name (add_symbol_segment),
2661 S_GET_NAME (fixP->fx_subsy),
2662 segment_name (sub_symbol_segment));
2666 if (fixP->fx_addsy)
2668 if (add_symbol_segment == this_segment
2669 && !TC_FORCE_RELOCATION_LOCAL (fixP))
2671 /* This fixup was made when the symbol's segment was
2672 SEG_UNKNOWN, but it is now in the local segment.
2673 So we know how to do the address without relocation. */
2674 add_number += S_GET_VALUE (fixP->fx_addsy);
2675 fixP->fx_offset = add_number;
2676 if (fixP->fx_pcrel)
2677 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
2678 fixP->fx_addsy = NULL;
2679 fixP->fx_pcrel = 0;
2681 else if (add_symbol_segment == absolute_section
2682 && !TC_FORCE_RELOCATION_ABS (fixP))
2684 add_number += S_GET_VALUE (fixP->fx_addsy);
2685 fixP->fx_offset = add_number;
2686 fixP->fx_addsy = NULL;
2688 else if (add_symbol_segment != undefined_section
2689 #ifdef BFD_ASSEMBLER
2690 && ! bfd_is_com_section (add_symbol_segment)
2691 #endif
2692 && MD_APPLY_SYM_VALUE (fixP))
2693 add_number += S_GET_VALUE (fixP->fx_addsy);
2696 if (fixP->fx_pcrel)
2698 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
2699 if (!fixP->fx_done && fixP->fx_addsy == NULL)
2701 /* There was no symbol required by this relocation.
2702 However, BFD doesn't really handle relocations
2703 without symbols well. So fake up a local symbol in
2704 the absolute section. */
2705 fixP->fx_addsy = abs_section_sym;
2709 if (!fixP->fx_done)
2710 md_apply_fix3 (fixP, &add_number, this_segment);
2712 if (!fixP->fx_done)
2714 ++seg_reloc_count;
2715 if (fixP->fx_addsy == NULL)
2716 fixP->fx_addsy = abs_section_sym;
2717 symbol_mark_used_in_reloc (fixP->fx_addsy);
2718 if (fixP->fx_subsy != NULL)
2719 symbol_mark_used_in_reloc (fixP->fx_subsy);
2722 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
2724 if (fixP->fx_size < sizeof (valueT))
2726 valueT mask;
2728 mask = 0;
2729 mask--; /* Set all bits to one. */
2730 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
2731 if ((add_number & mask) != 0 && (add_number & mask) != mask)
2733 char buf[50], buf2[50];
2734 sprint_value (buf, fragP->fr_address + fixP->fx_where);
2735 if (add_number > 1000)
2736 sprint_value (buf2, add_number);
2737 else
2738 sprintf (buf2, "%ld", (long) add_number);
2739 as_bad_where (fixP->fx_file, fixP->fx_line,
2740 _("value of %s too large for field of %d bytes at %s"),
2741 buf2, fixP->fx_size, buf);
2742 } /* Generic error checking. */
2744 #ifdef WARN_SIGNED_OVERFLOW_WORD
2745 /* Warn if a .word value is too large when treated as a signed
2746 number. We already know it is not too negative. This is to
2747 catch over-large switches generated by gcc on the 68k. */
2748 if (!flag_signed_overflow_ok
2749 && fixP->fx_size == 2
2750 && add_number > 0x7fff)
2751 as_bad_where (fixP->fx_file, fixP->fx_line,
2752 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
2753 (long) add_number,
2754 (long) (fragP->fr_address + fixP->fx_where));
2755 #endif
2756 } /* Not a bit fix. */
2758 #ifdef TC_VALIDATE_FIX
2759 skip: ATTRIBUTE_UNUSED_LABEL
2761 #endif
2762 #ifdef DEBUG5
2763 fprintf (stderr, "result:\n");
2764 print_fixup (fixP);
2765 #endif
2766 } /* For each fixS in this segment. */
2768 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2769 return seg_reloc_count;
2772 #endif /* defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS)) */
2774 void
2775 number_to_chars_bigendian (buf, val, n)
2776 char *buf;
2777 valueT val;
2778 int n;
2780 if (n <= 0)
2781 abort ();
2782 while (n--)
2784 buf[n] = val & 0xff;
2785 val >>= 8;
2789 void
2790 number_to_chars_littleendian (buf, val, n)
2791 char *buf;
2792 valueT val;
2793 int n;
2795 if (n <= 0)
2796 abort ();
2797 while (n--)
2799 *buf++ = val & 0xff;
2800 val >>= 8;
2804 void
2805 write_print_statistics (file)
2806 FILE *file;
2808 fprintf (file, "fixups: %d\n", n_fixups);
2811 /* For debugging. */
2812 extern int indent_level;
2814 void
2815 print_fixup (fixp)
2816 fixS *fixp;
2818 indent_level = 1;
2819 fprintf (stderr, "fix %lx %s:%d", (long) fixp, fixp->fx_file, fixp->fx_line);
2820 if (fixp->fx_pcrel)
2821 fprintf (stderr, " pcrel");
2822 if (fixp->fx_pcrel_adjust)
2823 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2824 if (fixp->fx_im_disp)
2826 #ifdef TC_NS32K
2827 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2828 #else
2829 fprintf (stderr, " im_disp");
2830 #endif
2832 if (fixp->fx_tcbit)
2833 fprintf (stderr, " tcbit");
2834 if (fixp->fx_done)
2835 fprintf (stderr, " done");
2836 fprintf (stderr, "\n size=%d frag=%lx where=%ld offset=%lx addnumber=%lx",
2837 fixp->fx_size, (long) fixp->fx_frag, (long) fixp->fx_where,
2838 (long) fixp->fx_offset, (long) fixp->fx_addnumber);
2839 #ifdef BFD_ASSEMBLER
2840 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2841 fixp->fx_r_type);
2842 #else
2843 #ifdef NEED_FX_R_TYPE
2844 fprintf (stderr, " r_type=%d", fixp->fx_r_type);
2845 #endif
2846 #endif
2847 if (fixp->fx_addsy)
2849 fprintf (stderr, "\n +<");
2850 print_symbol_value_1 (stderr, fixp->fx_addsy);
2851 fprintf (stderr, ">");
2853 if (fixp->fx_subsy)
2855 fprintf (stderr, "\n -<");
2856 print_symbol_value_1 (stderr, fixp->fx_subsy);
2857 fprintf (stderr, ">");
2859 fprintf (stderr, "\n");
2860 #ifdef TC_FIX_DATA_PRINT
2861 TC_FIX_DATA_PRINT (stderr, fixp);
2862 #endif