2000-05-29 Philip Blundell <philb@gnu.org>
[binutils.git] / gas / write.c
blob5a5c45b83aef144108d31dd4e8e857abf8f760fa
1 /* write.c - emit .o file
2 Copyright (C) 1986, 87, 90, 91, 92, 93, 94, 95, 96, 97, 98, 1999
3 Free Software Foundation, Inc.
5 This file is part of GAS, the GNU Assembler.
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 /* This thing should be set up to do byteordering correctly. But... */
24 #include "as.h"
25 #include "subsegs.h"
26 #include "obstack.h"
27 #include "output-file.h"
29 /* This looks like a good idea. Let's try turning it on always, for now. */
30 #undef BFD_FAST_SECTION_FILL
31 #define BFD_FAST_SECTION_FILL
33 /* The NOP_OPCODE is for the alignment fill value. Fill it with a nop
34 instruction so that the disassembler does not choke on it. */
35 #ifndef NOP_OPCODE
36 #define NOP_OPCODE 0x00
37 #endif
39 #ifndef TC_ADJUST_RELOC_COUNT
40 #define TC_ADJUST_RELOC_COUNT(FIXP,COUNT)
41 #endif
43 #ifndef TC_FORCE_RELOCATION
44 #define TC_FORCE_RELOCATION(FIXP) 0
45 #endif
47 #ifndef TC_FORCE_RELOCATION_SECTION
48 #define TC_FORCE_RELOCATION_SECTION(FIXP,SEG) TC_FORCE_RELOCATION(FIXP)
49 #endif
51 #ifndef MD_PCREL_FROM_SECTION
52 #define MD_PCREL_FROM_SECTION(FIXP, SEC) md_pcrel_from(FIXP)
53 #endif
55 #ifndef WORKING_DOT_WORD
56 extern CONST int md_short_jump_size;
57 extern CONST int md_long_jump_size;
58 #endif
60 int symbol_table_frozen;
61 void print_fixup PARAMS ((fixS *));
63 #ifdef BFD_ASSEMBLER
64 static void renumber_sections PARAMS ((bfd *, asection *, PTR));
66 /* We generally attach relocs to frag chains. However, after we have
67 chained these all together into a segment, any relocs we add after
68 that must be attached to a segment. This will include relocs added
69 in md_estimate_size_for_relax, for example. */
70 static int frags_chained = 0;
71 #endif
73 #ifndef BFD_ASSEMBLER
75 #ifndef MANY_SEGMENTS
76 struct frag *text_frag_root;
77 struct frag *data_frag_root;
78 struct frag *bss_frag_root;
80 struct frag *text_last_frag; /* Last frag in segment. */
81 struct frag *data_last_frag; /* Last frag in segment. */
82 static struct frag *bss_last_frag; /* Last frag in segment. */
83 #endif
85 #ifndef BFD
86 static object_headers headers;
87 #endif
89 long string_byte_count;
90 char *next_object_file_charP; /* Tracks object file bytes. */
92 #ifndef OBJ_VMS
93 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
94 #endif
96 #endif /* BFD_ASSEMBLER */
98 static int n_fixups;
100 #ifdef BFD_ASSEMBLER
101 static fixS *fix_new_internal PARAMS ((fragS *, int where, int size,
102 symbolS *add, symbolS *sub,
103 offsetT offset, int pcrel,
104 bfd_reloc_code_real_type r_type));
105 #else
106 static fixS *fix_new_internal PARAMS ((fragS *, int where, int size,
107 symbolS *add, symbolS *sub,
108 offsetT offset, int pcrel,
109 int r_type));
110 #endif
111 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
112 static long fixup_segment PARAMS ((fixS * fixP, segT this_segment_type));
113 #endif
114 static relax_addressT relax_align PARAMS ((relax_addressT addr, int align));
115 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
116 static fragS *chain_frchains_together_1 PARAMS ((segT, struct frchain *));
117 #endif
118 #ifdef BFD_ASSEMBLER
119 static void chain_frchains_together PARAMS ((bfd *, segT, PTR));
120 static void cvt_frag_to_fill PARAMS ((segT, fragS *));
121 static void relax_and_size_seg PARAMS ((bfd *, asection *, PTR));
122 static void adjust_reloc_syms PARAMS ((bfd *, asection *, PTR));
123 static void write_relocs PARAMS ((bfd *, asection *, PTR));
124 static void write_contents PARAMS ((bfd *, asection *, PTR));
125 static void set_symtab PARAMS ((void));
126 #endif
127 #if defined (BFD_ASSEMBLER) || (! defined (BFD) && ! defined (OBJ_AOUT))
128 static void merge_data_into_text PARAMS ((void));
129 #endif
130 #if ! defined (BFD_ASSEMBLER) && ! defined (BFD)
131 static void cvt_frag_to_fill PARAMS ((object_headers *, segT, fragS *));
132 static void remove_subsegs PARAMS ((frchainS *, int, fragS **, fragS **));
133 static void relax_and_size_all_segments PARAMS ((void));
134 #endif
137 * fix_new()
139 * Create a fixS in obstack 'notes'.
141 static fixS *
142 fix_new_internal (frag, where, size, add_symbol, sub_symbol, offset, pcrel,
143 r_type)
144 fragS *frag; /* Which frag? */
145 int where; /* Where in that frag? */
146 int size; /* 1, 2, or 4 usually. */
147 symbolS *add_symbol; /* X_add_symbol. */
148 symbolS *sub_symbol; /* X_op_symbol. */
149 offsetT offset; /* X_add_number. */
150 int pcrel; /* TRUE if PC-relative relocation. */
151 #ifdef BFD_ASSEMBLER
152 bfd_reloc_code_real_type r_type; /* Relocation type */
153 #else
154 int r_type; /* Relocation type */
155 #endif
157 fixS *fixP;
159 n_fixups++;
161 fixP = (fixS *) obstack_alloc (&notes, sizeof (fixS));
163 fixP->fx_frag = frag;
164 fixP->fx_where = where;
165 fixP->fx_size = size;
166 /* We've made fx_size a narrow field; check that it's wide enough. */
167 if (fixP->fx_size != size)
169 as_bad (_("field fx_size too small to hold %d"), size);
170 abort ();
172 fixP->fx_addsy = add_symbol;
173 fixP->fx_subsy = sub_symbol;
174 fixP->fx_offset = offset;
175 fixP->fx_pcrel = pcrel;
176 fixP->fx_plt = 0;
177 #if defined(NEED_FX_R_TYPE) || defined (BFD_ASSEMBLER)
178 fixP->fx_r_type = r_type;
179 #endif
180 fixP->fx_im_disp = 0;
181 fixP->fx_pcrel_adjust = 0;
182 fixP->fx_bit_fixP = 0;
183 fixP->fx_addnumber = 0;
184 fixP->fx_tcbit = 0;
185 fixP->fx_done = 0;
186 fixP->fx_no_overflow = 0;
187 fixP->fx_signed = 0;
189 #ifdef USING_CGEN
190 fixP->fx_cgen.insn = NULL;
191 fixP->fx_cgen.opinfo = 0;
192 #endif
194 #ifdef TC_FIX_TYPE
195 TC_INIT_FIX_DATA(fixP);
196 #endif
198 as_where (&fixP->fx_file, &fixP->fx_line);
200 /* Usually, we want relocs sorted numerically, but while
201 comparing to older versions of gas that have relocs
202 reverse sorted, it is convenient to have this compile
203 time option. xoxorich. */
207 #ifdef BFD_ASSEMBLER
208 fixS **seg_fix_rootP = (frags_chained
209 ? &seg_info (now_seg)->fix_root
210 : &frchain_now->fix_root);
211 fixS **seg_fix_tailP = (frags_chained
212 ? &seg_info (now_seg)->fix_tail
213 : &frchain_now->fix_tail);
214 #endif
216 #ifdef REVERSE_SORT_RELOCS
218 fixP->fx_next = *seg_fix_rootP;
219 *seg_fix_rootP = fixP;
221 #else /* REVERSE_SORT_RELOCS */
223 fixP->fx_next = NULL;
225 if (*seg_fix_tailP)
226 (*seg_fix_tailP)->fx_next = fixP;
227 else
228 *seg_fix_rootP = fixP;
229 *seg_fix_tailP = fixP;
231 #endif /* REVERSE_SORT_RELOCS */
235 return fixP;
238 /* Create a fixup relative to a symbol (plus a constant). */
240 fixS *
241 fix_new (frag, where, size, add_symbol, offset, pcrel, r_type)
242 fragS *frag; /* Which frag? */
243 int where; /* Where in that frag? */
244 int size; /* 1, 2, or 4 usually. */
245 symbolS *add_symbol; /* X_add_symbol. */
246 offsetT offset; /* X_add_number. */
247 int pcrel; /* TRUE if PC-relative relocation. */
248 #ifdef BFD_ASSEMBLER
249 bfd_reloc_code_real_type r_type; /* Relocation type */
250 #else
251 int r_type; /* Relocation type */
252 #endif
254 return fix_new_internal (frag, where, size, add_symbol,
255 (symbolS *) NULL, offset, pcrel, r_type);
258 /* Create a fixup for an expression. Currently we only support fixups
259 for difference expressions. That is itself more than most object
260 file formats support anyhow. */
262 fixS *
263 fix_new_exp (frag, where, size, exp, pcrel, r_type)
264 fragS *frag; /* Which frag? */
265 int where; /* Where in that frag? */
266 int size; /* 1, 2, or 4 usually. */
267 expressionS *exp; /* Expression. */
268 int pcrel; /* TRUE if PC-relative relocation. */
269 #ifdef BFD_ASSEMBLER
270 bfd_reloc_code_real_type r_type; /* Relocation type */
271 #else
272 int r_type; /* Relocation type */
273 #endif
275 symbolS *add = NULL;
276 symbolS *sub = NULL;
277 offsetT off = 0;
279 switch (exp->X_op)
281 case O_absent:
282 break;
284 case O_add:
285 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
286 the difference expression cannot immediately be reduced. */
288 symbolS *stmp = make_expr_symbol (exp);
289 exp->X_op = O_symbol;
290 exp->X_op_symbol = 0;
291 exp->X_add_symbol = stmp;
292 exp->X_add_number = 0;
293 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
296 case O_symbol_rva:
297 add = exp->X_add_symbol;
298 off = exp->X_add_number;
300 #if defined(BFD_ASSEMBLER)
301 r_type = BFD_RELOC_RVA;
302 #else
303 #if defined(TC_RVA_RELOC)
304 r_type = TC_RVA_RELOC;
305 #else
306 as_fatal(_("rva not supported"));
307 #endif
308 #endif
309 break;
311 case O_uminus:
312 sub = exp->X_add_symbol;
313 off = exp->X_add_number;
314 break;
316 case O_subtract:
317 sub = exp->X_op_symbol;
318 /* Fall through. */
319 case O_symbol:
320 add = exp->X_add_symbol;
321 /* Fall through. */
322 case O_constant:
323 off = exp->X_add_number;
324 break;
326 default:
327 add = make_expr_symbol (exp);
328 break;
331 return fix_new_internal (frag, where, size, add, sub, off,
332 pcrel, r_type);
335 /* Append a string onto another string, bumping the pointer along. */
336 void
337 append (charPP, fromP, length)
338 char **charPP;
339 char *fromP;
340 unsigned long length;
342 /* Don't trust memcpy() of 0 chars. */
343 if (length == 0)
344 return;
346 memcpy (*charPP, fromP, length);
347 *charPP += length;
350 #ifndef BFD_ASSEMBLER
351 int section_alignment[SEG_MAXIMUM_ORDINAL];
352 #endif
355 * This routine records the largest alignment seen for each segment.
356 * If the beginning of the segment is aligned on the worst-case
357 * boundary, all of the other alignments within it will work. At
358 * least one object format really uses this info.
360 void
361 record_alignment (seg, align)
362 /* Segment to which alignment pertains */
363 segT seg;
364 /* Alignment, as a power of 2 (e.g., 1 => 2-byte boundary, 2 => 4-byte
365 boundary, etc.) */
366 int align;
368 if (seg == absolute_section)
369 return;
370 #ifdef BFD_ASSEMBLER
371 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
372 bfd_set_section_alignment (stdoutput, seg, align);
373 #else
374 if (align > section_alignment[(int) seg])
375 section_alignment[(int) seg] = align;
376 #endif
379 #ifdef BFD_ASSEMBLER
381 /* Reset the section indices after removing the gas created sections. */
383 static void
384 renumber_sections (abfd, sec, countparg)
385 bfd *abfd ATTRIBUTE_UNUSED;
386 asection *sec;
387 PTR countparg;
389 int *countp = (int *) countparg;
391 sec->index = *countp;
392 ++*countp;
395 #endif /* defined (BFD_ASSEMBLER) */
397 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
399 static fragS *
400 chain_frchains_together_1 (section, frchp)
401 segT section;
402 struct frchain *frchp;
404 fragS dummy, *prev_frag = &dummy;
405 #ifdef BFD_ASSEMBLER
406 fixS fix_dummy, *prev_fix = &fix_dummy;
407 #endif
409 for (; frchp && frchp->frch_seg == section; frchp = frchp->frch_next)
411 prev_frag->fr_next = frchp->frch_root;
412 prev_frag = frchp->frch_last;
413 assert (prev_frag->fr_type != 0);
414 #ifdef BFD_ASSEMBLER
415 if (frchp->fix_root != (fixS *) NULL)
417 if (seg_info (section)->fix_root == (fixS *) NULL)
418 seg_info (section)->fix_root = frchp->fix_root;
419 prev_fix->fx_next = frchp->fix_root;
420 seg_info (section)->fix_tail = frchp->fix_tail;
421 prev_fix = frchp->fix_tail;
423 #endif
425 assert (prev_frag->fr_type != 0);
426 prev_frag->fr_next = 0;
427 return prev_frag;
430 #endif
432 #ifdef BFD_ASSEMBLER
434 static void
435 chain_frchains_together (abfd, section, xxx)
436 bfd *abfd ATTRIBUTE_UNUSED;
437 segT section;
438 PTR xxx ATTRIBUTE_UNUSED;
440 segment_info_type *info;
442 /* BFD may have introduced its own sections without using
443 subseg_new, so it is possible that seg_info is NULL. */
444 info = seg_info (section);
445 if (info != (segment_info_type *) NULL)
446 info->frchainP->frch_last
447 = chain_frchains_together_1 (section, info->frchainP);
449 /* Now that we've chained the frags together, we must add new fixups
450 to the segment, not to the frag chain. */
451 frags_chained = 1;
454 #endif
456 #if !defined (BFD) && !defined (BFD_ASSEMBLER)
458 static void
459 remove_subsegs (head, seg, root, last)
460 frchainS *head;
461 int seg;
462 fragS **root;
463 fragS **last;
465 *root = head->frch_root;
466 *last = chain_frchains_together_1 (seg, head);
469 #endif /* BFD */
471 #if defined (BFD_ASSEMBLER) || !defined (BFD)
473 #ifdef BFD_ASSEMBLER
474 static void
475 cvt_frag_to_fill (sec, fragP)
476 segT sec;
477 fragS *fragP;
478 #else
479 static void
480 cvt_frag_to_fill (headersP, sec, fragP)
481 object_headers *headersP;
482 segT sec;
483 fragS *fragP;
484 #endif
486 switch (fragP->fr_type)
488 case rs_align:
489 case rs_align_code:
490 case rs_org:
491 case rs_space:
492 #ifdef HANDLE_ALIGN
493 HANDLE_ALIGN (fragP);
494 #endif
495 know (fragP->fr_next != NULL);
496 fragP->fr_offset = (fragP->fr_next->fr_address
497 - fragP->fr_address
498 - fragP->fr_fix) / fragP->fr_var;
499 if (fragP->fr_offset < 0)
501 as_bad_where (fragP->fr_file, fragP->fr_line,
502 _("attempt to .org/.space backwards? (%ld)"),
503 (long) fragP->fr_offset);
505 fragP->fr_type = rs_fill;
506 break;
508 case rs_fill:
509 break;
511 case rs_leb128:
513 valueT value = S_GET_VALUE (fragP->fr_symbol);
514 int size;
516 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
517 fragP->fr_subtype);
519 fragP->fr_fix += size;
520 fragP->fr_type = rs_fill;
521 fragP->fr_var = 0;
522 fragP->fr_offset = 0;
523 fragP->fr_symbol = NULL;
525 break;
527 case rs_cfa:
528 eh_frame_convert_frag (fragP);
529 break;
531 case rs_machine_dependent:
532 #ifdef BFD_ASSEMBLER
533 md_convert_frag (stdoutput, sec, fragP);
534 #else
535 md_convert_frag (headersP, sec, fragP);
536 #endif
538 assert (fragP->fr_next == NULL
539 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
540 == fragP->fr_fix));
543 * After md_convert_frag, we make the frag into a ".space 0".
544 * Md_convert_frag() should set up any fixSs and constants
545 * required.
547 frag_wane (fragP);
548 break;
550 #ifndef WORKING_DOT_WORD
551 case rs_broken_word:
553 struct broken_word *lie;
555 if (fragP->fr_subtype)
557 fragP->fr_fix += md_short_jump_size;
558 for (lie = (struct broken_word *) (fragP->fr_symbol);
559 lie && lie->dispfrag == fragP;
560 lie = lie->next_broken_word)
561 if (lie->added == 1)
562 fragP->fr_fix += md_long_jump_size;
564 frag_wane (fragP);
566 break;
567 #endif
569 default:
570 BAD_CASE (fragP->fr_type);
571 break;
575 #endif /* defined (BFD_ASSEMBLER) || !defined (BFD) */
577 #ifdef BFD_ASSEMBLER
578 static void
579 relax_and_size_seg (abfd, sec, xxx)
580 bfd *abfd;
581 asection *sec;
582 PTR xxx ATTRIBUTE_UNUSED;
584 flagword flags;
585 fragS *fragp;
586 segment_info_type *seginfo;
587 int x;
588 valueT size, newsize;
590 subseg_change (sec, 0);
592 flags = bfd_get_section_flags (abfd, sec);
594 seginfo = seg_info (sec);
595 if (seginfo && seginfo->frchainP)
597 relax_segment (seginfo->frchainP->frch_root, sec);
598 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
599 cvt_frag_to_fill (sec, fragp);
600 for (fragp = seginfo->frchainP->frch_root;
601 fragp->fr_next;
602 fragp = fragp->fr_next)
603 /* walk to last elt */;
604 size = fragp->fr_address + fragp->fr_fix;
606 else
607 size = 0;
609 if (size > 0 && ! seginfo->bss)
610 flags |= SEC_HAS_CONTENTS;
612 /* @@ This is just an approximation. */
613 if (seginfo && seginfo->fix_root)
614 flags |= SEC_RELOC;
615 else
616 flags &= ~SEC_RELOC;
617 x = bfd_set_section_flags (abfd, sec, flags);
618 assert (x == true);
620 newsize = md_section_align (sec, size);
621 x = bfd_set_section_size (abfd, sec, newsize);
622 assert (x == true);
624 /* If the size had to be rounded up, add some padding in the last
625 non-empty frag. */
626 assert (newsize >= size);
627 if (size != newsize)
629 fragS *last = seginfo->frchainP->frch_last;
630 fragp = seginfo->frchainP->frch_root;
631 while (fragp->fr_next != last)
632 fragp = fragp->fr_next;
633 last->fr_address = size;
634 fragp->fr_offset += newsize - size;
637 #ifdef tc_frob_section
638 tc_frob_section (sec);
639 #endif
640 #ifdef obj_frob_section
641 obj_frob_section (sec);
642 #endif
645 #ifdef DEBUG2
646 static void
647 dump_section_relocs (abfd, sec, stream_)
648 bfd *abfd ATTRIBUTE_UNUSED;
649 asection *sec;
650 char *stream_;
652 FILE *stream = (FILE *) stream_;
653 segment_info_type *seginfo = seg_info (sec);
654 fixS *fixp = seginfo->fix_root;
656 if (!fixp)
657 return;
659 fprintf (stream, "sec %s relocs:\n", sec->name);
660 while (fixp)
662 symbolS *s = fixp->fx_addsy;
664 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
665 (int) fixp->fx_r_type);
666 if (s == NULL)
667 fprintf (stream, "no sym\n");
668 else
670 print_symbol_value_1 (stream, s);
671 fprintf (stream, "\n");
673 fixp = fixp->fx_next;
676 #else
677 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
678 #endif
680 #ifndef EMIT_SECTION_SYMBOLS
681 #define EMIT_SECTION_SYMBOLS 1
682 #endif
684 static void
685 adjust_reloc_syms (abfd, sec, xxx)
686 bfd *abfd ATTRIBUTE_UNUSED;
687 asection *sec;
688 PTR xxx ATTRIBUTE_UNUSED;
690 segment_info_type *seginfo = seg_info (sec);
691 fixS *fixp;
693 if (seginfo == NULL)
694 return;
696 dump_section_relocs (abfd, sec, stderr);
698 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
699 if (fixp->fx_done)
700 /* ignore it */;
701 else if (fixp->fx_addsy)
703 symbolS *sym;
704 asection *symsec;
706 #ifdef DEBUG5
707 fprintf (stderr, "\n\nadjusting fixup:\n");
708 print_fixup (fixp);
709 #endif
711 sym = fixp->fx_addsy;
713 /* All symbols should have already been resolved at this
714 point. It is possible to see unresolved expression
715 symbols, though, since they are not in the regular symbol
716 table. */
717 if (sym != NULL)
718 resolve_symbol_value (sym, 1);
720 if (fixp->fx_subsy != NULL)
721 resolve_symbol_value (fixp->fx_subsy, 1);
723 /* If this symbol is equated to an undefined symbol, convert
724 the fixup to being against that symbol. */
725 if (sym != NULL && symbol_equated_p (sym)
726 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
728 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
729 sym = symbol_get_value_expression (sym)->X_add_symbol;
730 fixp->fx_addsy = sym;
733 if (sym != NULL && symbol_mri_common_p (sym))
735 /* These symbols are handled specially in fixup_segment. */
736 goto done;
739 symsec = S_GET_SEGMENT (sym);
741 if (symsec == NULL)
742 abort ();
744 if (bfd_is_abs_section (symsec))
746 /* The fixup_segment routine will not use this symbol in a
747 relocation unless TC_FORCE_RELOCATION returns 1. */
748 if (TC_FORCE_RELOCATION (fixp))
750 symbol_mark_used_in_reloc (fixp->fx_addsy);
751 #ifdef UNDEFINED_DIFFERENCE_OK
752 if (fixp->fx_subsy != NULL)
753 symbol_mark_used_in_reloc (fixp->fx_subsy);
754 #endif
756 goto done;
759 /* If it's one of these sections, assume the symbol is
760 definitely going to be output. The code in
761 md_estimate_size_before_relax in tc-mips.c uses this test
762 as well, so if you change this code you should look at that
763 code. */
764 if (bfd_is_und_section (symsec)
765 || bfd_is_com_section (symsec))
767 symbol_mark_used_in_reloc (fixp->fx_addsy);
768 #ifdef UNDEFINED_DIFFERENCE_OK
769 /* We have the difference of an undefined symbol and some
770 other symbol. Make sure to mark the other symbol as used
771 in a relocation so that it will always be output. */
772 if (fixp->fx_subsy)
773 symbol_mark_used_in_reloc (fixp->fx_subsy);
774 #endif
775 goto done;
778 /* Don't try to reduce relocs which refer to non-local symbols
779 in .linkonce sections. It can lead to confusion when a
780 debugging section refers to a .linkonce section. I hope
781 this will always be correct. */
782 if (symsec != sec && ! S_IS_LOCAL (sym))
784 boolean linkonce;
786 linkonce = false;
787 #ifdef BFD_ASSEMBLER
788 if ((bfd_get_section_flags (stdoutput, symsec) & SEC_LINK_ONCE)
789 != 0)
790 linkonce = true;
791 #endif
792 #ifdef OBJ_ELF
793 /* The GNU toolchain uses an extension for ELF: a section
794 beginning with the magic string .gnu.linkonce is a
795 linkonce section. */
796 if (strncmp (segment_name (symsec), ".gnu.linkonce",
797 sizeof ".gnu.linkonce" - 1) == 0)
798 linkonce = true;
799 #endif
801 if (linkonce)
803 symbol_mark_used_in_reloc (fixp->fx_addsy);
804 #ifdef UNDEFINED_DIFFERENCE_OK
805 if (fixp->fx_subsy != NULL)
806 symbol_mark_used_in_reloc (fixp->fx_subsy);
807 #endif
808 goto done;
812 /* Since we're reducing to section symbols, don't attempt to reduce
813 anything that's already using one. */
814 if (symbol_section_p (sym))
816 symbol_mark_used_in_reloc (fixp->fx_addsy);
817 goto done;
820 #ifdef BFD_ASSEMBLER
821 /* We can never adjust a reloc against a weak symbol. If we
822 did, and the weak symbol was overridden by a real symbol
823 somewhere else, then our relocation would be pointing at
824 the wrong area of memory. */
825 if (S_IS_WEAK (sym))
827 symbol_mark_used_in_reloc (fixp->fx_addsy);
828 goto done;
830 #endif
832 /* Is there some other reason we can't adjust this one? (E.g.,
833 call/bal links in i960-bout symbols.) */
834 #ifdef obj_fix_adjustable
835 if (! obj_fix_adjustable (fixp))
837 symbol_mark_used_in_reloc (fixp->fx_addsy);
838 goto done;
840 #endif
842 /* Is there some other (target cpu dependent) reason we can't adjust
843 this one? (E.g. relocations involving function addresses on
844 the PA. */
845 #ifdef tc_fix_adjustable
846 if (! tc_fix_adjustable (fixp))
848 symbol_mark_used_in_reloc (fixp->fx_addsy);
849 goto done;
851 #endif
853 /* If the section symbol isn't going to be output, the relocs
854 at least should still work. If not, figure out what to do
855 when we run into that case.
857 We refetch the segment when calling section_symbol, rather
858 than using symsec, because S_GET_VALUE may wind up changing
859 the section when it calls resolve_symbol_value. */
860 fixp->fx_offset += S_GET_VALUE (sym);
861 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
862 symbol_mark_used_in_reloc (fixp->fx_addsy);
863 #ifdef DEBUG5
864 fprintf (stderr, "\nadjusted fixup:\n");
865 print_fixup (fixp);
866 #endif
868 done:
871 #if 1/*def RELOC_REQUIRES_SYMBOL*/
872 else
874 /* There was no symbol required by this relocation. However,
875 BFD doesn't really handle relocations without symbols well.
876 (At least, the COFF support doesn't.) So for now we fake up
877 a local symbol in the absolute section. */
879 fixp->fx_addsy = section_symbol (absolute_section);
880 /* fixp->fx_addsy->sy_used_in_reloc = 1; */
882 #endif
884 dump_section_relocs (abfd, sec, stderr);
887 static void
888 write_relocs (abfd, sec, xxx)
889 bfd *abfd;
890 asection *sec;
891 PTR xxx ATTRIBUTE_UNUSED;
893 segment_info_type *seginfo = seg_info (sec);
894 int i;
895 unsigned int n;
896 arelent **relocs;
897 fixS *fixp;
898 char *err;
900 /* If seginfo is NULL, we did not create this section; don't do
901 anything with it. */
902 if (seginfo == NULL)
903 return;
905 fixup_segment (seginfo->fix_root, sec);
907 n = 0;
908 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
909 n++;
911 #ifndef RELOC_EXPANSION_POSSIBLE
912 /* Set up reloc information as well. */
913 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
914 memset ((char*)relocs, 0, n * sizeof (arelent*));
916 i = 0;
917 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
919 arelent *reloc;
920 bfd_reloc_status_type s;
921 symbolS *sym;
923 if (fixp->fx_done)
925 n--;
926 continue;
929 /* If this is an undefined symbol which was equated to another
930 symbol, then use generate the reloc against the latter symbol
931 rather than the former. */
932 sym = fixp->fx_addsy;
933 while (symbol_equated_p (sym)
934 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
936 symbolS *n;
938 /* We must avoid looping, as that can occur with a badly
939 written program. */
940 n = symbol_get_value_expression (sym)->X_add_symbol;
941 if (n == sym)
942 break;
943 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
944 sym = n;
946 fixp->fx_addsy = sym;
948 reloc = tc_gen_reloc (sec, fixp);
949 if (!reloc)
951 n--;
952 continue;
955 #if 0
956 /* This test is triggered inappropriately for the SH. */
957 if (fixp->fx_where + fixp->fx_size
958 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
959 abort ();
960 #endif
962 s = bfd_install_relocation (stdoutput, reloc,
963 fixp->fx_frag->fr_literal,
964 fixp->fx_frag->fr_address,
965 sec, &err);
966 switch (s)
968 case bfd_reloc_ok:
969 break;
970 case bfd_reloc_overflow:
971 as_bad_where (fixp->fx_file, fixp->fx_line, _("relocation overflow"));
972 break;
973 case bfd_reloc_outofrange:
974 as_bad_where (fixp->fx_file, fixp->fx_line, _("relocation out of range"));
975 break;
976 default:
977 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
978 fixp->fx_file, fixp->fx_line, s);
980 relocs[i++] = reloc;
982 #else
983 n = n * MAX_RELOC_EXPANSION;
984 /* Set up reloc information as well. */
985 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
987 i = 0;
988 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
990 arelent **reloc;
991 char *data;
992 bfd_reloc_status_type s;
993 symbolS *sym;
994 int j;
996 if (fixp->fx_done)
998 n--;
999 continue;
1002 /* If this is an undefined symbol which was equated to another
1003 symbol, then use generate the reloc against the latter symbol
1004 rather than the former. */
1005 sym = fixp->fx_addsy;
1006 while (symbol_equated_p (sym)
1007 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
1008 sym = symbol_get_value_expression (sym)->X_add_symbol;
1009 fixp->fx_addsy = sym;
1011 reloc = tc_gen_reloc (sec, fixp);
1013 for (j = 0; reloc[j]; j++)
1015 relocs[i++] = reloc[j];
1016 assert(i <= n);
1018 data = fixp->fx_frag->fr_literal + fixp->fx_where;
1019 if (fixp->fx_where + fixp->fx_size
1020 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
1021 as_bad_where (fixp->fx_file, fixp->fx_line,
1022 _("internal error: fixup not contained within frag"));
1023 for (j = 0; reloc[j]; j++)
1025 s = bfd_install_relocation (stdoutput, reloc[j],
1026 fixp->fx_frag->fr_literal,
1027 fixp->fx_frag->fr_address,
1028 sec, &err);
1029 switch (s)
1031 case bfd_reloc_ok:
1032 break;
1033 case bfd_reloc_overflow:
1034 as_bad_where (fixp->fx_file, fixp->fx_line,
1035 _("relocation overflow"));
1036 break;
1037 default:
1038 as_fatal (_("%s:%u: bad return from bfd_install_relocation"),
1039 fixp->fx_file, fixp->fx_line);
1043 n = i;
1044 #endif
1046 #ifdef DEBUG4
1048 int i, j, nsyms;
1049 asymbol **sympp;
1050 sympp = bfd_get_outsymbols (stdoutput);
1051 nsyms = bfd_get_symcount (stdoutput);
1052 for (i = 0; i < n; i++)
1053 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1055 for (j = 0; j < nsyms; j++)
1056 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1057 break;
1058 if (j == nsyms)
1059 abort ();
1062 #endif
1064 if (n)
1065 bfd_set_reloc (stdoutput, sec, relocs, n);
1066 else
1067 bfd_set_section_flags (abfd, sec,
1068 (bfd_get_section_flags (abfd, sec)
1069 & (flagword) ~SEC_RELOC));
1071 #ifdef SET_SECTION_RELOCS
1072 SET_SECTION_RELOCS (sec, relocs, n);
1073 #endif
1075 #ifdef DEBUG3
1077 int i;
1078 arelent *r;
1079 asymbol *s;
1080 fprintf (stderr, "relocs for sec %s\n", sec->name);
1081 for (i = 0; i < n; i++)
1083 r = relocs[i];
1084 s = *r->sym_ptr_ptr;
1085 fprintf (stderr, " reloc %2d @%08x off %4x : sym %-10s addend %x\n",
1086 i, r, r->address, s->name, r->addend);
1089 #endif
1092 static void
1093 write_contents (abfd, sec, xxx)
1094 bfd *abfd ATTRIBUTE_UNUSED;
1095 asection *sec;
1096 PTR xxx ATTRIBUTE_UNUSED;
1098 segment_info_type *seginfo = seg_info (sec);
1099 unsigned long offset = 0;
1100 fragS *f;
1102 /* Write out the frags. */
1103 if (seginfo == NULL
1104 || ! (bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1105 return;
1107 for (f = seginfo->frchainP->frch_root;
1109 f = f->fr_next)
1111 int x;
1112 unsigned long fill_size;
1113 char *fill_literal;
1114 long count;
1116 assert (f->fr_type == rs_fill);
1117 if (f->fr_fix)
1119 x = bfd_set_section_contents (stdoutput, sec,
1120 f->fr_literal, (file_ptr) offset,
1121 (bfd_size_type) f->fr_fix);
1122 if (x == false)
1124 bfd_perror (stdoutput->filename);
1125 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1126 exit (EXIT_FAILURE);
1128 offset += f->fr_fix;
1130 fill_literal = f->fr_literal + f->fr_fix;
1131 fill_size = f->fr_var;
1132 count = f->fr_offset;
1133 assert (count >= 0);
1134 if (fill_size && count)
1136 char buf[256];
1137 if (fill_size > sizeof(buf))
1139 /* Do it the old way. Can this ever happen? */
1140 while (count--)
1142 x = bfd_set_section_contents (stdoutput, sec,
1143 fill_literal,
1144 (file_ptr) offset,
1145 (bfd_size_type) fill_size);
1146 if (x == false)
1148 bfd_perror (stdoutput->filename);
1149 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1150 exit (EXIT_FAILURE);
1152 offset += fill_size;
1155 else
1157 /* Build a buffer full of fill objects and output it as
1158 often as necessary. This saves on the overhead of
1159 potentially lots of bfd_set_section_contents calls. */
1160 int n_per_buf, i;
1161 if (fill_size == 1)
1163 n_per_buf = sizeof (buf);
1164 memset (buf, *fill_literal, n_per_buf);
1166 else
1168 char *bufp;
1169 n_per_buf = sizeof(buf)/fill_size;
1170 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1171 memcpy(bufp, fill_literal, fill_size);
1173 for (; count > 0; count -= n_per_buf)
1175 n_per_buf = n_per_buf > count ? count : n_per_buf;
1176 x = bfd_set_section_contents (stdoutput, sec,
1177 buf, (file_ptr) offset,
1178 (bfd_size_type) n_per_buf * fill_size);
1179 if (x != true)
1180 as_fatal (_("Cannot write to output file."));
1181 offset += n_per_buf * fill_size;
1187 #endif
1189 #if defined(BFD_ASSEMBLER) || (!defined (BFD) && !defined(OBJ_AOUT))
1190 static void
1191 merge_data_into_text ()
1193 #if defined(BFD_ASSEMBLER) || defined(MANY_SEGMENTS)
1194 seg_info (text_section)->frchainP->frch_last->fr_next =
1195 seg_info (data_section)->frchainP->frch_root;
1196 seg_info (text_section)->frchainP->frch_last =
1197 seg_info (data_section)->frchainP->frch_last;
1198 seg_info (data_section)->frchainP = 0;
1199 #else
1200 fixS *tmp;
1202 text_last_frag->fr_next = data_frag_root;
1203 text_last_frag = data_last_frag;
1204 data_last_frag = NULL;
1205 data_frag_root = NULL;
1206 if (text_fix_root)
1208 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
1209 tmp->fx_next = data_fix_root;
1210 text_fix_tail = data_fix_tail;
1212 else
1213 text_fix_root = data_fix_root;
1214 data_fix_root = NULL;
1215 #endif
1217 #endif /* BFD_ASSEMBLER || (! BFD && ! OBJ_AOUT) */
1219 #if !defined (BFD_ASSEMBLER) && !defined (BFD)
1220 static void
1221 relax_and_size_all_segments ()
1223 fragS *fragP;
1225 relax_segment (text_frag_root, SEG_TEXT);
1226 relax_segment (data_frag_root, SEG_DATA);
1227 relax_segment (bss_frag_root, SEG_BSS);
1229 * Now the addresses of frags are correct within the segment.
1232 know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
1233 H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
1234 text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
1237 * Join the 2 segments into 1 huge segment.
1238 * To do this, re-compute every rn_address in the SEG_DATA frags.
1239 * Then join the data frags after the text frags.
1241 * Determine a_data [length of data segment].
1243 if (data_frag_root)
1245 register relax_addressT slide;
1247 know ((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
1249 H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
1250 data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
1251 slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
1252 #ifdef OBJ_BOUT
1253 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
1254 /* For b.out: If the data section has a strict alignment
1255 requirement, its load address in the .o file will be
1256 rounded up from the size of the text section. These
1257 two values are *not* the same! Similarly for the bss
1258 section.... */
1259 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
1260 #endif
1262 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
1264 fragP->fr_address += slide;
1265 } /* for each data frag */
1267 know (text_last_frag != 0);
1268 text_last_frag->fr_next = data_frag_root;
1270 else
1272 H_SET_DATA_SIZE (&headers, 0);
1275 #ifdef OBJ_BOUT
1276 /* See above comments on b.out data section address. */
1278 long bss_vma;
1279 if (data_last_frag == 0)
1280 bss_vma = H_GET_TEXT_SIZE (&headers);
1281 else
1282 bss_vma = data_last_frag->fr_address;
1283 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
1284 bss_address_frag.fr_address = bss_vma;
1286 #else /* ! OBJ_BOUT */
1287 bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
1288 H_GET_DATA_SIZE (&headers));
1290 #endif /* ! OBJ_BOUT */
1292 /* Slide all the frags */
1293 if (bss_frag_root)
1295 relax_addressT slide = bss_address_frag.fr_address;
1297 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
1299 fragP->fr_address += slide;
1300 } /* for each bss frag */
1303 if (bss_last_frag)
1304 H_SET_BSS_SIZE (&headers,
1305 bss_last_frag->fr_address - bss_frag_root->fr_address);
1306 else
1307 H_SET_BSS_SIZE (&headers, 0);
1309 #endif /* ! BFD_ASSEMBLER && ! BFD */
1311 #if defined (BFD_ASSEMBLER) || !defined (BFD)
1313 #ifdef BFD_ASSEMBLER
1314 static void
1315 set_symtab ()
1317 int nsyms;
1318 asymbol **asympp;
1319 symbolS *symp;
1320 boolean result;
1321 extern PTR bfd_alloc PARAMS ((bfd *, size_t));
1323 /* Count symbols. We can't rely on a count made by the loop in
1324 write_object_file, because *_frob_file may add a new symbol or
1325 two. */
1326 nsyms = 0;
1327 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1328 nsyms++;
1330 if (nsyms)
1332 int i;
1334 asympp = (asymbol **) bfd_alloc (stdoutput,
1335 nsyms * sizeof (asymbol *));
1336 symp = symbol_rootP;
1337 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1339 asympp[i] = symbol_get_bfdsym (symp);
1340 symbol_mark_written (symp);
1343 else
1344 asympp = 0;
1345 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1346 assert (result == true);
1347 symbol_table_frozen = 1;
1349 #endif
1351 /* Finish the subsegments. After every sub-segment, we fake an
1352 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1353 ".fill 0" because that is the kind of frag that requires least
1354 thought. ".align" frags like to have a following frag since that
1355 makes calculating their intended length trivial. */
1357 #ifndef SUB_SEGMENT_ALIGN
1358 #ifdef BFD_ASSEMBLER
1359 #define SUB_SEGMENT_ALIGN(SEG) (0)
1360 #else
1361 #define SUB_SEGMENT_ALIGN(SEG) (2)
1362 #endif
1363 #endif
1365 void
1366 subsegs_finish ()
1368 struct frchain *frchainP;
1370 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
1372 subseg_set (frchainP->frch_seg, frchainP->frch_subseg);
1374 /* This now gets called even if we had errors. In that case,
1375 any alignment is meaningless, and, moreover, will look weird
1376 if we are generating a listing. */
1377 frag_align (had_errors () ? 0 : SUB_SEGMENT_ALIGN (now_seg),
1378 subseg_text_p (now_seg) ? NOP_OPCODE : 0,
1381 /* frag_align will have left a new frag.
1382 Use this last frag for an empty ".fill".
1384 For this segment ...
1385 Create a last frag. Do not leave a "being filled in frag". */
1387 frag_wane (frag_now);
1388 frag_now->fr_fix = 0;
1389 know (frag_now->fr_next == NULL);
1393 /* Write the object file. */
1395 void
1396 write_object_file ()
1398 #if ! defined (BFD_ASSEMBLER) || ! defined (WORKING_DOT_WORD)
1399 fragS *fragP; /* Track along all frags. */
1400 #endif
1402 /* Do we really want to write it? */
1404 int n_warns, n_errs;
1405 n_warns = had_warnings ();
1406 n_errs = had_errors ();
1407 /* The -Z flag indicates that an object file should be generated,
1408 regardless of warnings and errors. */
1409 if (flag_always_generate_output)
1411 if (n_warns || n_errs)
1412 as_warn (_("%d error%s, %d warning%s, generating bad object file.\n"),
1413 n_errs, n_errs == 1 ? "" : "s",
1414 n_warns, n_warns == 1 ? "" : "s");
1416 else
1418 if (n_errs)
1419 as_fatal (_("%d error%s, %d warning%s, no object file generated.\n"),
1420 n_errs, n_errs == 1 ? "" : "s",
1421 n_warns, n_warns == 1 ? "" : "s");
1425 #ifdef OBJ_VMS
1426 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1427 a routine to check for the definition of the procedure "_main",
1428 and if so -- fix it up so that it can be program entry point. */
1429 vms_check_for_main ();
1430 #endif /* OBJ_VMS */
1432 /* From now on, we don't care about sub-segments. Build one frag chain
1433 for each segment. Linked thru fr_next. */
1435 #ifdef BFD_ASSEMBLER
1436 /* Remove the sections created by gas for its own purposes. */
1438 asection **seclist, *sec;
1439 int i;
1441 seclist = &stdoutput->sections;
1442 while (seclist && *seclist)
1444 sec = *seclist;
1445 while (sec == reg_section || sec == expr_section)
1447 sec = sec->next;
1448 *seclist = sec;
1449 stdoutput->section_count--;
1450 if (!sec)
1451 break;
1453 if (*seclist)
1454 seclist = &(*seclist)->next;
1456 i = 0;
1457 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1460 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1461 #else
1462 remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
1463 remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
1464 remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
1465 #endif
1467 /* We have two segments. If user gave -R flag, then we must put the
1468 data frags into the text segment. Do this before relaxing so
1469 we know to take advantage of -R and make shorter addresses. */
1470 #if !defined (OBJ_AOUT) || defined (BFD_ASSEMBLER)
1471 if (flag_readonly_data_in_text)
1473 merge_data_into_text ();
1475 #endif
1477 #ifdef BFD_ASSEMBLER
1478 bfd_map_over_sections (stdoutput, relax_and_size_seg, (char *) 0);
1479 #else
1480 relax_and_size_all_segments ();
1481 #endif /* BFD_ASSEMBLER */
1483 #ifndef BFD_ASSEMBLER
1486 * Crawl the symbol chain.
1488 * For each symbol whose value depends on a frag, take the address of
1489 * that frag and subsume it into the value of the symbol.
1490 * After this, there is just one way to lookup a symbol value.
1491 * Values are left in their final state for object file emission.
1492 * We adjust the values of 'L' local symbols, even if we do
1493 * not intend to emit them to the object file, because their values
1494 * are needed for fix-ups.
1496 * Unless we saw a -L flag, remove all symbols that begin with 'L'
1497 * from the symbol chain. (They are still pointed to by the fixes.)
1499 * Count the remaining symbols.
1500 * Assign a symbol number to each symbol.
1501 * Count the number of string-table chars we will emit.
1502 * Put this info into the headers as appropriate.
1505 know (zero_address_frag.fr_address == 0);
1506 string_byte_count = sizeof (string_byte_count);
1508 obj_crawl_symbol_chain (&headers);
1510 if (string_byte_count == sizeof (string_byte_count))
1511 string_byte_count = 0;
1513 H_SET_STRING_SIZE (&headers, string_byte_count);
1516 * Addresses of frags now reflect addresses we use in the object file.
1517 * Symbol values are correct.
1518 * Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
1519 * Also converting any machine-dependent frags using md_convert_frag();
1521 subseg_change (SEG_TEXT, 0);
1523 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1525 /* At this point we have linked all the frags into a single
1526 chain. However, cvt_frag_to_fill may call md_convert_frag
1527 which may call fix_new. We need to ensure that fix_new adds
1528 the fixup to the right section. */
1529 if (fragP == data_frag_root)
1530 subseg_change (SEG_DATA, 0);
1532 cvt_frag_to_fill (&headers, SEG_TEXT, fragP);
1534 /* Some assert macros don't work with # directives mixed in. */
1535 #ifndef NDEBUG
1536 if (!(fragP->fr_next == NULL
1537 #ifdef OBJ_BOUT
1538 || fragP->fr_next == data_frag_root
1539 #endif
1540 || ((fragP->fr_next->fr_address - fragP->fr_address)
1541 == (fragP->fr_fix + fragP->fr_offset * fragP->fr_var))))
1542 abort ();
1543 #endif
1545 #endif /* ! BFD_ASSEMBLER */
1547 #ifndef WORKING_DOT_WORD
1549 struct broken_word *lie;
1550 struct broken_word **prevP;
1552 prevP = &broken_words;
1553 for (lie = broken_words; lie; lie = lie->next_broken_word)
1554 if (!lie->added)
1556 expressionS exp;
1558 subseg_change (lie->seg, lie->subseg);
1559 exp.X_op = O_subtract;
1560 exp.X_add_symbol = lie->add;
1561 exp.X_op_symbol = lie->sub;
1562 exp.X_add_number = lie->addnum;
1563 #ifdef BFD_ASSEMBLER
1564 #ifdef TC_CONS_FIX_NEW
1565 TC_CONS_FIX_NEW (lie->frag,
1566 lie->word_goes_here - lie->frag->fr_literal,
1567 2, &exp);
1568 #else
1569 fix_new_exp (lie->frag,
1570 lie->word_goes_here - lie->frag->fr_literal,
1571 2, &exp, 0, BFD_RELOC_16);
1572 #endif
1573 #else
1574 #if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
1575 fix_new_exp (lie->frag,
1576 lie->word_goes_here - lie->frag->fr_literal,
1577 2, &exp, 0, NO_RELOC);
1578 #else
1579 #ifdef TC_NS32K
1580 fix_new_ns32k_exp (lie->frag,
1581 lie->word_goes_here - lie->frag->fr_literal,
1582 2, &exp, 0, 0, 2, 0, 0);
1583 #else
1584 fix_new_exp (lie->frag,
1585 lie->word_goes_here - lie->frag->fr_literal,
1586 2, &exp, 0, 0);
1587 #endif /* TC_NS32K */
1588 #endif /* TC_SPARC|TC_A29K|NEED_FX_R_TYPE */
1589 #endif /* BFD_ASSEMBLER */
1590 *prevP = lie->next_broken_word;
1592 else
1593 prevP = &(lie->next_broken_word);
1595 for (lie = broken_words; lie;)
1597 struct broken_word *untruth;
1598 char *table_ptr;
1599 addressT table_addr;
1600 addressT from_addr, to_addr;
1601 int n, m;
1603 subseg_change (lie->seg, lie->subseg);
1604 fragP = lie->dispfrag;
1606 /* Find out how many broken_words go here. */
1607 n = 0;
1608 for (untruth = lie; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
1609 if (untruth->added == 1)
1610 n++;
1612 table_ptr = lie->dispfrag->fr_opcode;
1613 table_addr = lie->dispfrag->fr_address + (table_ptr - lie->dispfrag->fr_literal);
1614 /* Create the jump around the long jumps. This is a short
1615 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1616 from_addr = table_addr;
1617 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1618 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
1619 table_ptr += md_short_jump_size;
1620 table_addr += md_short_jump_size;
1622 for (m = 0; lie && lie->dispfrag == fragP; m++, lie = lie->next_broken_word)
1624 if (lie->added == 2)
1625 continue;
1626 /* Patch the jump table */
1627 /* This is the offset from ??? to table_ptr+0 */
1628 to_addr = table_addr - S_GET_VALUE (lie->sub);
1629 #ifdef BFD_ASSEMBLER
1630 to_addr -= symbol_get_frag (lie->sub)->fr_address;
1631 #endif
1632 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1633 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_addr, lie);
1634 #endif
1635 md_number_to_chars (lie->word_goes_here, to_addr, 2);
1636 for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
1638 if (untruth->use_jump == lie)
1639 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
1642 /* Install the long jump */
1643 /* this is a long jump from table_ptr+0 to the final target */
1644 from_addr = table_addr;
1645 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1646 #ifdef BFD_ASSEMBLER
1647 to_addr += symbol_get_frag (lie->add)->fr_address;
1648 #endif
1649 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
1650 table_ptr += md_long_jump_size;
1651 table_addr += md_long_jump_size;
1655 #endif /* not WORKING_DOT_WORD */
1657 #ifndef BFD_ASSEMBLER
1658 #ifndef OBJ_VMS
1659 { /* not vms */
1660 char *the_object_file;
1661 long object_file_size;
1663 * Scan every FixS performing fixups. We had to wait until now to do
1664 * this because md_convert_frag() may have made some fixSs.
1666 int trsize, drsize;
1668 subseg_change (SEG_TEXT, 0);
1669 trsize = md_reloc_size * fixup_segment (text_fix_root, SEG_TEXT);
1670 subseg_change (SEG_DATA, 0);
1671 drsize = md_reloc_size * fixup_segment (data_fix_root, SEG_DATA);
1672 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
1674 /* FIXME move this stuff into the pre-write-hook */
1675 H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
1676 H_SET_ENTRY_POINT (&headers, 0);
1678 obj_pre_write_hook (&headers); /* extra coff stuff */
1680 object_file_size = H_GET_FILE_SIZE (&headers);
1681 next_object_file_charP = the_object_file = xmalloc (object_file_size);
1683 output_file_create (out_file_name);
1685 obj_header_append (&next_object_file_charP, &headers);
1687 know ((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE (&headers));
1690 * Emit code.
1692 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1694 register long count;
1695 register char *fill_literal;
1696 register long fill_size;
1698 PROGRESS (1);
1699 know (fragP->fr_type == rs_fill);
1700 append (&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
1701 fill_literal = fragP->fr_literal + fragP->fr_fix;
1702 fill_size = fragP->fr_var;
1703 know (fragP->fr_offset >= 0);
1705 for (count = fragP->fr_offset; count; count--)
1707 append (&next_object_file_charP, fill_literal, (unsigned long) fill_size);
1708 } /* for each */
1710 } /* for each code frag. */
1712 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers)));
1715 * Emit relocations.
1717 obj_emit_relocations (&next_object_file_charP, text_fix_root, (relax_addressT) 0);
1718 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers)));
1719 #ifdef TC_I960
1720 /* Make addresses in data relocation directives relative to beginning of
1721 * first data fragment, not end of last text fragment: alignment of the
1722 * start of the data segment may place a gap between the segments.
1724 obj_emit_relocations (&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
1725 #else /* TC_I960 */
1726 obj_emit_relocations (&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
1727 #endif /* TC_I960 */
1729 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers)));
1732 * Emit line number entries.
1734 OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
1735 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers) + H_GET_LINENO_SIZE (&headers)));
1738 * Emit symbols.
1740 obj_emit_symbols (&next_object_file_charP, symbol_rootP);
1741 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers) + H_GET_LINENO_SIZE (&headers) + H_GET_SYMBOL_TABLE_SIZE (&headers)));
1744 * Emit strings.
1747 if (string_byte_count > 0)
1749 obj_emit_strings (&next_object_file_charP);
1750 } /* only if we have a string table */
1752 #ifdef BFD_HEADERS
1753 bfd_seek (stdoutput, 0, 0);
1754 bfd_write (the_object_file, 1, object_file_size, stdoutput);
1755 #else
1757 /* Write the data to the file */
1758 output_file_append (the_object_file, object_file_size, out_file_name);
1759 free (the_object_file);
1760 #endif
1761 } /* non vms output */
1762 #else /* OBJ_VMS */
1764 * Now do the VMS-dependent part of writing the object file
1766 vms_write_object_file (H_GET_TEXT_SIZE (&headers),
1767 H_GET_DATA_SIZE (&headers),
1768 H_GET_BSS_SIZE (&headers),
1769 text_frag_root, data_frag_root);
1770 #endif /* OBJ_VMS */
1771 #else /* BFD_ASSEMBLER */
1773 /* Resolve symbol values. This needs to be done before processing
1774 the relocations. */
1775 if (symbol_rootP)
1777 symbolS *symp;
1779 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1780 resolve_symbol_value (symp, 1);
1782 resolve_local_symbol_values ();
1784 PROGRESS (1);
1786 #ifdef tc_frob_file_before_adjust
1787 tc_frob_file_before_adjust ();
1788 #endif
1789 #ifdef obj_frob_file_before_adjust
1790 obj_frob_file_before_adjust ();
1791 #endif
1793 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *)0);
1795 /* Set up symbol table, and write it out. */
1796 if (symbol_rootP)
1798 symbolS *symp;
1800 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1802 int punt = 0;
1803 const char *name;
1805 if (symbol_mri_common_p (symp))
1807 if (S_IS_EXTERNAL (symp))
1808 as_bad (_("%s: global symbols not supported in common sections"),
1809 S_GET_NAME (symp));
1810 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1811 continue;
1814 name = S_GET_NAME (symp);
1815 if (name)
1817 const char *name2 = decode_local_label_name ((char *)S_GET_NAME (symp));
1818 /* They only differ if `name' is a fb or dollar local
1819 label name. */
1820 if (name2 != name && ! S_IS_DEFINED (symp))
1821 as_bad (_("local label %s is not defined"), name2);
1824 /* Do it again, because adjust_reloc_syms might introduce
1825 more symbols. They'll probably only be section symbols,
1826 but they'll still need to have the values computed. */
1827 resolve_symbol_value (symp, 1);
1829 /* Skip symbols which were equated to undefined or common
1830 symbols. */
1831 if (symbol_equated_p (symp)
1832 && (! S_IS_DEFINED (symp) || S_IS_COMMON (symp)))
1834 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1835 continue;
1838 /* So far, common symbols have been treated like undefined symbols.
1839 Put them in the common section now. */
1840 if (S_IS_DEFINED (symp) == 0
1841 && S_GET_VALUE (symp) != 0)
1842 S_SET_SEGMENT (symp, bfd_com_section_ptr);
1843 #if 0
1844 printf ("symbol `%s'\n\t@%x: value=%d flags=%x seg=%s\n",
1845 S_GET_NAME (symp), symp,
1846 S_GET_VALUE (symp),
1847 symbol_get_bfdsym (symp)->flags,
1848 segment_name (S_GET_SEGMENT (symp)));
1849 #endif
1851 #ifdef obj_frob_symbol
1852 obj_frob_symbol (symp, punt);
1853 #endif
1854 #ifdef tc_frob_symbol
1855 if (! punt || symbol_used_in_reloc_p (symp))
1856 tc_frob_symbol (symp, punt);
1857 #endif
1859 /* If we don't want to keep this symbol, splice it out of
1860 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1861 want section symbols. Otherwise, we skip local symbols
1862 and symbols that the frob_symbol macros told us to punt,
1863 but we keep such symbols if they are used in relocs. */
1864 if ((! EMIT_SECTION_SYMBOLS
1865 && symbol_section_p (symp))
1866 /* Note that S_IS_EXTERN and S_IS_LOCAL are not always
1867 opposites. Sometimes the former checks flags and the
1868 latter examines the name... */
1869 || (!S_IS_EXTERN (symp)
1870 && (S_IS_LOCAL (symp) || punt)
1871 && ! symbol_used_in_reloc_p (symp)))
1873 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1874 /* After symbol_remove, symbol_next(symp) still returns
1875 the one that came after it in the chain. So we don't
1876 need to do any extra cleanup work here. */
1878 continue;
1881 /* Make sure we really got a value for the symbol. */
1882 if (! symbol_resolved_p (symp))
1884 as_bad (_("can't resolve value for symbol \"%s\""),
1885 S_GET_NAME (symp));
1886 symbol_mark_resolved (symp);
1889 /* Set the value into the BFD symbol. Up til now the value
1890 has only been kept in the gas symbolS struct. */
1891 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1895 PROGRESS (1);
1897 /* Now do any format-specific adjustments to the symbol table, such
1898 as adding file symbols. */
1899 #ifdef tc_adjust_symtab
1900 tc_adjust_symtab ();
1901 #endif
1902 #ifdef obj_adjust_symtab
1903 obj_adjust_symtab ();
1904 #endif
1906 /* Now that all the sizes are known, and contents correct, we can
1907 start writing to the file. */
1908 set_symtab ();
1910 /* If *_frob_file changes the symbol value at this point, it is
1911 responsible for moving the changed value into symp->bsym->value
1912 as well. Hopefully all symbol value changing can be done in
1913 *_frob_symbol. */
1914 #ifdef tc_frob_file
1915 tc_frob_file ();
1916 #endif
1917 #ifdef obj_frob_file
1918 obj_frob_file ();
1919 #endif
1921 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
1923 #ifdef tc_frob_file_after_relocs
1924 tc_frob_file_after_relocs ();
1925 #endif
1926 #ifdef obj_frob_file_after_relocs
1927 obj_frob_file_after_relocs ();
1928 #endif
1930 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
1931 #endif /* BFD_ASSEMBLER */
1933 #endif /* ! BFD */
1936 * relax_segment()
1938 * Now we have a segment, not a crowd of sub-segments, we can make fr_address
1939 * values.
1941 * Relax the frags.
1943 * After this, all frags in this segment have addresses that are correct
1944 * within the segment. Since segments live in different file addresses,
1945 * these frag addresses may not be the same as final object-file addresses.
1948 #ifdef TC_GENERIC_RELAX_TABLE
1950 static int is_dnrange PARAMS ((fragS *, fragS *));
1952 /* Subroutines of relax_segment. */
1953 static int
1954 is_dnrange (f1, f2)
1955 fragS *f1;
1956 fragS *f2;
1958 for (; f1; f1 = f1->fr_next)
1959 if (f1->fr_next == f2)
1960 return 1;
1961 return 0;
1964 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
1966 long
1967 relax_frag (fragP, stretch)
1968 fragS *fragP;
1969 long stretch;
1971 const relax_typeS *this_type;
1972 const relax_typeS *start_type;
1973 relax_substateT next_state;
1974 relax_substateT this_state;
1975 long aim, target, growth;
1976 symbolS *symbolP = fragP->fr_symbol;
1977 long offset = fragP->fr_offset;
1978 /* Recompute was_address by undoing "+= stretch" done by relax_segment. */
1979 unsigned long was_address = fragP->fr_address - stretch;
1980 unsigned long address = fragP->fr_address;
1981 const relax_typeS *table = TC_GENERIC_RELAX_TABLE;
1983 this_state = fragP->fr_subtype;
1984 start_type = this_type = table + this_state;
1985 target = offset;
1987 if (symbolP)
1989 #ifndef DIFF_EXPR_OK
1990 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
1991 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
1992 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
1993 || (S_GET_SEGMENT (symbolP) == SEG_BSS)
1994 || (S_GET_SEGMENT (symbolP) == SEG_TEXT));
1995 #endif
1996 know (symbolP->sy_frag);
1997 #endif
1998 know (!(S_GET_SEGMENT (symbolP) == absolute_section)
1999 || symbolP->sy_frag == &zero_address_frag);
2000 target += S_GET_VALUE (symbolP) + symbol_get_frag (symbolP)->fr_address;
2002 /* If frag has yet to be reached on this pass,
2003 assume it will move by STRETCH just as we did.
2004 If this is not so, it will be because some frag
2005 between grows, and that will force another pass.
2007 Beware zero-length frags.
2009 There should be a faster way to do this. */
2011 if (symbol_get_frag (symbolP)->fr_address >= was_address
2012 && is_dnrange (fragP, symbol_get_frag (symbolP)))
2014 target += stretch;
2018 aim = target - address - fragP->fr_fix;
2019 #ifdef TC_PCREL_ADJUST
2020 /* Currently only the ns32k family needs this */
2021 aim += TC_PCREL_ADJUST(fragP);
2022 /*#else*/
2023 /* This machine doesn't want to use pcrel_adjust.
2024 In that case, pcrel_adjust should be zero. */
2025 /* assert (fragP->fr_targ.ns32k.pcrel_adjust == 0);*/
2026 #endif
2027 #ifdef md_prepare_relax_scan /* formerly called M68K_AIM_KLUDGE */
2028 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2029 #endif
2031 if (aim < 0)
2033 /* Look backwards. */
2034 for (next_state = this_type->rlx_more; next_state;)
2035 if (aim >= this_type->rlx_backward)
2036 next_state = 0;
2037 else
2039 /* Grow to next state. */
2040 this_state = next_state;
2041 this_type = table + this_state;
2042 next_state = this_type->rlx_more;
2045 else
2047 /* Look forwards. */
2048 for (next_state = this_type->rlx_more; next_state;)
2049 if (aim <= this_type->rlx_forward)
2050 next_state = 0;
2051 else
2053 /* Grow to next state. */
2054 this_state = next_state;
2055 this_type = table + this_state;
2056 next_state = this_type->rlx_more;
2060 growth = this_type->rlx_length - start_type->rlx_length;
2061 if (growth != 0)
2062 fragP->fr_subtype = this_state;
2063 return growth;
2066 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2068 /* Relax_align. Advance location counter to next address that has 'alignment'
2069 lowest order bits all 0s, return size of adjustment made. */
2070 static relax_addressT
2071 relax_align (address, alignment)
2072 register relax_addressT address; /* Address now. */
2073 register int alignment; /* Alignment (binary). */
2075 relax_addressT mask;
2076 relax_addressT new_address;
2078 mask = ~((~0) << alignment);
2079 new_address = (address + mask) & (~mask);
2080 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2081 if (linkrelax)
2082 /* We must provide lots of padding, so the linker can discard it
2083 when needed. The linker will not add extra space, ever. */
2084 new_address += (1 << alignment);
2085 #endif
2086 return (new_address - address);
2089 void
2090 relax_segment (segment_frag_root, segment)
2091 struct frag *segment_frag_root;
2092 segT segment;
2094 register struct frag *fragP;
2095 register relax_addressT address;
2096 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2097 know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
2098 #endif
2099 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2100 subseg_change (segment, 0);
2102 /* For each frag in segment: count and store (a 1st guess of)
2103 fr_address. */
2104 address = 0;
2105 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2107 fragP->fr_address = address;
2108 address += fragP->fr_fix;
2110 switch (fragP->fr_type)
2112 case rs_fill:
2113 address += fragP->fr_offset * fragP->fr_var;
2114 break;
2116 case rs_align:
2117 case rs_align_code:
2119 addressT offset = relax_align (address, (int) fragP->fr_offset);
2121 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2122 offset = 0;
2124 if (offset % fragP->fr_var != 0)
2126 as_bad (_("alignment padding (%lu bytes) not a multiple of %ld"),
2127 (unsigned long) offset, (long) fragP->fr_var);
2128 offset -= (offset % fragP->fr_var);
2131 address += offset;
2133 break;
2135 case rs_org:
2136 case rs_space:
2137 /* Assume .org is nugatory. It will grow with 1st relax. */
2138 break;
2140 case rs_machine_dependent:
2141 address += md_estimate_size_before_relax (fragP, segment);
2142 break;
2144 #ifndef WORKING_DOT_WORD
2145 /* Broken words don't concern us yet */
2146 case rs_broken_word:
2147 break;
2148 #endif
2150 case rs_leb128:
2151 /* Initial guess is always 1; doing otherwise can result in
2152 stable solutions that are larger than the minimum. */
2153 address += fragP->fr_offset = 1;
2154 break;
2156 case rs_cfa:
2157 address += eh_frame_estimate_size_before_relax (fragP);
2158 break;
2160 default:
2161 BAD_CASE (fragP->fr_type);
2162 break;
2163 } /* switch(fr_type) */
2164 } /* for each frag in the segment */
2166 /* Do relax(). */
2168 long stretch; /* May be any size, 0 or negative. */
2169 /* Cumulative number of addresses we have */
2170 /* relaxed this pass. */
2171 /* We may have relaxed more than one address. */
2172 long stretched; /* Have we stretched on this pass? */
2173 /* This is 'cuz stretch may be zero, when, in fact some piece of code
2174 grew, and another shrank. If a branch instruction doesn't fit anymore,
2175 we could be scrod. */
2179 stretch = stretched = 0;
2180 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2182 long growth = 0;
2183 addressT was_address;
2184 offsetT offset;
2185 symbolS *symbolP;
2187 was_address = fragP->fr_address;
2188 address = fragP->fr_address += stretch;
2189 symbolP = fragP->fr_symbol;
2190 offset = fragP->fr_offset;
2192 switch (fragP->fr_type)
2194 case rs_fill: /* .fill never relaxes. */
2195 growth = 0;
2196 break;
2198 #ifndef WORKING_DOT_WORD
2199 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2200 for it I do not want to write it. I do not want to have
2201 anything to do with it. This is not the proper way to
2202 implement this misfeature. */
2203 case rs_broken_word:
2205 struct broken_word *lie;
2206 struct broken_word *untruth;
2208 /* Yes this is ugly (storing the broken_word pointer
2209 in the symbol slot). Still, this whole chunk of
2210 code is ugly, and I don't feel like doing anything
2211 about it. Think of it as stubbornness in action. */
2212 growth = 0;
2213 for (lie = (struct broken_word *) (fragP->fr_symbol);
2214 lie && lie->dispfrag == fragP;
2215 lie = lie->next_broken_word)
2218 if (lie->added)
2219 continue;
2221 offset = (symbol_get_frag (lie->add)->fr_address
2222 + S_GET_VALUE (lie->add)
2223 + lie->addnum
2224 - (symbol_get_frag (lie->sub)->fr_address
2225 + S_GET_VALUE (lie->sub)));
2226 if (offset <= -32768 || offset >= 32767)
2228 if (flag_warn_displacement)
2230 char buf[50];
2231 sprint_value (buf, (addressT) lie->addnum);
2232 as_warn (_(".word %s-%s+%s didn't fit"),
2233 S_GET_NAME (lie->add),
2234 S_GET_NAME (lie->sub),
2235 buf);
2237 lie->added = 1;
2238 if (fragP->fr_subtype == 0)
2240 fragP->fr_subtype++;
2241 growth += md_short_jump_size;
2243 for (untruth = lie->next_broken_word;
2244 untruth && untruth->dispfrag == lie->dispfrag;
2245 untruth = untruth->next_broken_word)
2246 if ((symbol_get_frag (untruth->add)
2247 == symbol_get_frag (lie->add))
2248 && (S_GET_VALUE (untruth->add)
2249 == S_GET_VALUE (lie->add)))
2251 untruth->added = 2;
2252 untruth->use_jump = lie;
2254 growth += md_long_jump_size;
2258 break;
2259 } /* case rs_broken_word */
2260 #endif
2261 case rs_align:
2262 case rs_align_code:
2264 addressT oldoff, newoff;
2266 oldoff = relax_align (was_address + fragP->fr_fix,
2267 (int) offset);
2268 newoff = relax_align (address + fragP->fr_fix,
2269 (int) offset);
2271 if (fragP->fr_subtype != 0)
2273 if (oldoff > fragP->fr_subtype)
2274 oldoff = 0;
2275 if (newoff > fragP->fr_subtype)
2276 newoff = 0;
2279 growth = newoff - oldoff;
2281 break;
2283 case rs_org:
2285 long target = offset;
2286 long after;
2288 if (symbolP)
2290 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2291 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2292 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2293 || (S_GET_SEGMENT (symbolP) == SEG_TEXT)
2294 || S_GET_SEGMENT (symbolP) == SEG_BSS);
2295 know (symbolP->sy_frag);
2296 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2297 || (symbolP->sy_frag == &zero_address_frag));
2298 #endif
2299 target += (S_GET_VALUE (symbolP)
2300 + symbol_get_frag (symbolP)->fr_address);
2301 } /* if we have a symbol */
2303 know (fragP->fr_next);
2304 after = fragP->fr_next->fr_address;
2305 growth = target - after;
2306 if (growth < 0)
2308 /* Growth may be negative, but variable part of frag
2309 cannot have fewer than 0 chars. That is, we can't
2310 .org backwards. */
2311 as_bad_where (fragP->fr_file, fragP->fr_line,
2312 _("attempt to .org backwards ignored"));
2314 /* We've issued an error message. Change the
2315 frag to avoid cascading errors. */
2316 fragP->fr_type = rs_align;
2317 fragP->fr_subtype = 0;
2318 fragP->fr_offset = 0;
2319 fragP->fr_fix = after - address;
2320 growth = stretch;
2323 growth -= stretch; /* This is an absolute growth factor */
2324 break;
2327 case rs_space:
2328 if (symbolP)
2330 growth = S_GET_VALUE (symbolP);
2331 if (symbol_get_frag (symbolP) != &zero_address_frag
2332 || S_IS_COMMON (symbolP)
2333 || ! S_IS_DEFINED (symbolP))
2334 as_bad_where (fragP->fr_file, fragP->fr_line,
2335 _(".space specifies non-absolute value"));
2336 fragP->fr_symbol = 0;
2337 if (growth < 0)
2339 as_warn (_(".space or .fill with negative value, ignored"));
2340 growth = 0;
2343 else
2344 growth = 0;
2345 break;
2347 case rs_machine_dependent:
2348 #ifdef md_relax_frag
2349 growth = md_relax_frag (fragP, stretch);
2350 #else
2351 #ifdef TC_GENERIC_RELAX_TABLE
2352 /* The default way to relax a frag is to look through
2353 TC_GENERIC_RELAX_TABLE. */
2354 growth = relax_frag (fragP, stretch);
2355 #endif /* TC_GENERIC_RELAX_TABLE */
2356 #endif
2357 break;
2359 case rs_leb128:
2361 valueT value;
2362 int size;
2364 value = resolve_symbol_value (fragP->fr_symbol, 0);
2365 size = sizeof_leb128 (value, fragP->fr_subtype);
2366 growth = size - fragP->fr_offset;
2367 fragP->fr_offset = size;
2369 break;
2371 case rs_cfa:
2372 growth = eh_frame_relax_frag (fragP);
2373 break;
2375 default:
2376 BAD_CASE (fragP->fr_type);
2377 break;
2379 if (growth)
2381 stretch += growth;
2382 stretched++;
2384 } /* For each frag in the segment. */
2386 while (stretched); /* Until nothing further to relax. */
2387 } /* do_relax */
2390 * We now have valid fr_address'es for each frag.
2394 * All fr_address's are correct, relative to their own segment.
2395 * We have made all the fixS we will ever make.
2397 } /* relax_segment() */
2399 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
2401 #ifndef TC_RELOC_RTSYM_LOC_FIXUP
2402 #define TC_RELOC_RTSYM_LOC_FIXUP(X) (1)
2403 #endif
2405 /* fixup_segment()
2407 Go through all the fixS's in a segment and see which ones can be
2408 handled now. (These consist of fixS where we have since discovered
2409 the value of a symbol, or the address of the frag involved.)
2410 For each one, call md_apply_fix to put the fix into the frag data.
2412 Result is a count of how many relocation structs will be needed to
2413 handle the remaining fixS's that we couldn't completely handle here.
2414 These will be output later by emit_relocations(). */
2416 static long
2417 fixup_segment (fixP, this_segment_type)
2418 register fixS *fixP;
2419 segT this_segment_type; /* N_TYPE bits for segment. */
2421 long seg_reloc_count = 0;
2422 symbolS *add_symbolP;
2423 symbolS *sub_symbolP;
2424 valueT add_number;
2425 int size;
2426 char *place;
2427 long where;
2428 int pcrel, plt;
2429 fragS *fragP;
2430 segT add_symbol_segment = absolute_section;
2432 /* If the linker is doing the relaxing, we must not do any fixups.
2434 Well, strictly speaking that's not true -- we could do any that are
2435 PC-relative and don't cross regions that could change size. And for the
2436 i960 (the only machine for which we've got a relaxing linker right now),
2437 we might be able to turn callx/callj into bal anyways in cases where we
2438 know the maximum displacement. */
2439 if (linkrelax)
2441 for (; fixP; fixP = fixP->fx_next)
2442 seg_reloc_count++;
2443 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2444 return seg_reloc_count;
2447 for (; fixP; fixP = fixP->fx_next)
2450 #ifdef DEBUG5
2451 fprintf (stderr, "\nprocessing fixup:\n");
2452 print_fixup (fixP);
2453 #endif
2456 fragP = fixP->fx_frag;
2457 know (fragP);
2458 where = fixP->fx_where;
2459 place = fragP->fr_literal + where;
2460 size = fixP->fx_size;
2461 add_symbolP = fixP->fx_addsy;
2462 #ifdef TC_VALIDATE_FIX
2463 TC_VALIDATE_FIX (fixP, this_segment_type, skip);
2464 #endif
2465 sub_symbolP = fixP->fx_subsy;
2466 add_number = fixP->fx_offset;
2467 pcrel = fixP->fx_pcrel;
2468 plt = fixP->fx_plt;
2470 if (add_symbolP != NULL
2471 && symbol_mri_common_p (add_symbolP))
2473 know (add_symbolP->sy_value.X_op == O_symbol);
2474 add_number += S_GET_VALUE (add_symbolP);
2475 fixP->fx_offset = add_number;
2476 add_symbolP = fixP->fx_addsy =
2477 symbol_get_value_expression (add_symbolP)->X_add_symbol;
2480 if (add_symbolP)
2481 add_symbol_segment = S_GET_SEGMENT (add_symbolP);
2483 if (sub_symbolP)
2485 resolve_symbol_value (sub_symbolP, 1);
2486 if (add_symbolP == NULL || add_symbol_segment == absolute_section)
2488 if (add_symbolP != NULL)
2490 add_number += S_GET_VALUE (add_symbolP);
2491 add_symbolP = NULL;
2492 fixP->fx_addsy = NULL;
2495 /* It's just -sym */
2496 if (S_GET_SEGMENT (sub_symbolP) == absolute_section)
2498 add_number -= S_GET_VALUE (sub_symbolP);
2499 fixP->fx_subsy = NULL;
2501 else if (pcrel
2502 && S_GET_SEGMENT (sub_symbolP) == this_segment_type)
2504 /* Should try converting to a constant. */
2505 goto bad_sub_reloc;
2507 else
2508 bad_sub_reloc:
2509 as_bad_where (fixP->fx_file, fixP->fx_line,
2510 _("Negative of non-absolute symbol %s"),
2511 S_GET_NAME (sub_symbolP));
2513 else if (S_GET_SEGMENT (sub_symbolP) == add_symbol_segment
2514 && SEG_NORMAL (add_symbol_segment))
2516 /* Difference of 2 symbols from same segment.
2517 Can't make difference of 2 undefineds: 'value' means
2518 something different for N_UNDF. */
2519 #ifdef TC_I960
2520 /* Makes no sense to use the difference of 2 arbitrary symbols
2521 as the target of a call instruction. */
2522 if (fixP->fx_tcbit)
2523 as_bad_where (fixP->fx_file, fixP->fx_line,
2524 _("callj to difference of 2 symbols"));
2525 #endif /* TC_I960 */
2526 add_number += S_GET_VALUE (add_symbolP) -
2527 S_GET_VALUE (sub_symbolP);
2529 add_symbolP = NULL;
2530 pcrel = 0; /* No further pcrel processing. */
2532 /* Let the target machine make the final determination
2533 as to whether or not a relocation will be needed to
2534 handle this fixup. */
2535 if (!TC_FORCE_RELOCATION_SECTION (fixP, this_segment_type))
2537 fixP->fx_pcrel = 0;
2538 fixP->fx_addsy = NULL;
2539 fixP->fx_subsy = NULL;
2542 else
2544 /* Different segments in subtraction. */
2545 know (!(S_IS_EXTERNAL (sub_symbolP)
2546 && (S_GET_SEGMENT (sub_symbolP) == absolute_section)));
2548 if ((S_GET_SEGMENT (sub_symbolP) == absolute_section))
2549 add_number -= S_GET_VALUE (sub_symbolP);
2551 #ifdef DIFF_EXPR_OK
2552 else if (S_GET_SEGMENT (sub_symbolP) == this_segment_type
2553 #if 0 /* Do this even if it's already described as pc-relative. For example,
2554 on the m68k, an operand of "pc@(foo-.-2)" should address "foo" in a
2555 pc-relative mode. */
2556 && pcrel
2557 #endif
2560 /* Make it pc-relative. */
2561 add_number += (MD_PCREL_FROM_SECTION (fixP, this_segment_type)
2562 - S_GET_VALUE (sub_symbolP));
2563 pcrel = 1;
2564 fixP->fx_pcrel = 1;
2565 sub_symbolP = 0;
2566 fixP->fx_subsy = 0;
2568 #endif
2569 #ifdef UNDEFINED_DIFFERENCE_OK
2570 /* The PA needs this for PIC code generation. We basically
2571 don't want to do anything if we have the difference of two
2572 symbols at this point. */
2573 else if (1)
2575 /* Leave it alone. */
2577 #endif
2578 #ifdef BFD_ASSEMBLER
2579 else if (fixP->fx_r_type == BFD_RELOC_GPREL32
2580 || fixP->fx_r_type == BFD_RELOC_GPREL16)
2582 /* Leave it alone. */
2584 #endif
2585 else
2587 char buf[50];
2588 sprint_value (buf, fragP->fr_address + where);
2589 as_bad_where (fixP->fx_file, fixP->fx_line,
2590 _("Subtraction of two symbols in different sections \"%s\" {%s section} - \"%s\" {%s section} at file address %s."),
2591 S_GET_NAME (add_symbolP),
2592 segment_name (S_GET_SEGMENT (add_symbolP)),
2593 S_GET_NAME (sub_symbolP),
2594 segment_name (S_GET_SEGMENT (sub_symbolP)),
2595 buf);
2600 if (add_symbolP)
2602 if (add_symbol_segment == this_segment_type && pcrel && !plt
2603 && TC_RELOC_RTSYM_LOC_FIXUP (fixP))
2606 * This fixup was made when the symbol's segment was
2607 * SEG_UNKNOWN, but it is now in the local segment.
2608 * So we know how to do the address without relocation.
2610 #ifdef TC_I960
2611 /* reloc_callj() may replace a 'call' with a 'calls' or a
2612 'bal', in which cases it modifies *fixP as appropriate.
2613 In the case of a 'calls', no further work is required,
2614 and *fixP has been set up to make the rest of the code
2615 below a no-op. */
2616 reloc_callj (fixP);
2617 #endif /* TC_I960 */
2619 add_number += S_GET_VALUE (add_symbolP);
2620 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment_type);
2621 pcrel = 0; /* Lie. Don't want further pcrel processing. */
2623 /* Let the target machine make the final determination
2624 as to whether or not a relocation will be needed to
2625 handle this fixup. */
2626 if (!TC_FORCE_RELOCATION (fixP))
2628 fixP->fx_pcrel = 0;
2629 fixP->fx_addsy = NULL;
2632 else
2634 if (add_symbol_segment == absolute_section
2635 && ! pcrel)
2637 #ifdef TC_I960
2638 /* See comment about reloc_callj() above. */
2639 reloc_callj (fixP);
2640 #endif /* TC_I960 */
2641 add_number += S_GET_VALUE (add_symbolP);
2643 /* Let the target machine make the final determination
2644 as to whether or not a relocation will be needed to
2645 handle this fixup. */
2647 if (!TC_FORCE_RELOCATION (fixP))
2649 fixP->fx_addsy = NULL;
2650 add_symbolP = NULL;
2653 else if (add_symbol_segment == undefined_section
2654 #ifdef BFD_ASSEMBLER
2655 || bfd_is_com_section (add_symbol_segment)
2656 #endif
2659 #ifdef TC_I960
2660 if ((int) fixP->fx_bit_fixP == 13)
2662 /* This is a COBR instruction. They have only a
2663 * 13-bit displacement and are only to be used
2664 * for local branches: flag as error, don't generate
2665 * relocation.
2667 as_bad_where (fixP->fx_file, fixP->fx_line,
2668 _("can't use COBR format with external label"));
2669 fixP->fx_addsy = NULL;
2670 fixP->fx_done = 1;
2671 continue;
2672 } /* COBR */
2673 #endif /* TC_I960 */
2675 #ifdef OBJ_COFF
2676 #ifdef TE_I386AIX
2677 if (S_IS_COMMON (add_symbolP))
2678 add_number += S_GET_VALUE (add_symbolP);
2679 #endif /* TE_I386AIX */
2680 #endif /* OBJ_COFF */
2681 ++seg_reloc_count;
2683 else
2685 seg_reloc_count++;
2686 #if !(defined (TC_V850) && defined (OBJ_ELF))
2687 #if !(defined (TC_M68K) && defined (OBJ_ELF))
2688 #if !(defined (TC_ARM) && defined (OBJ_ELF))
2689 #if !(defined (TC_I960) && defined (OBJ_ELF))
2690 #if !defined (TC_I386) || !(defined (OBJ_ELF) || defined (OBJ_COFF)) || defined (TE_PE)
2691 add_number += S_GET_VALUE (add_symbolP);
2692 #endif
2693 #endif
2694 #endif
2695 #endif
2696 #endif
2701 if (pcrel)
2703 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment_type);
2704 if (add_symbolP == 0)
2706 #ifndef BFD_ASSEMBLER
2707 fixP->fx_addsy = &abs_symbol;
2708 #else
2709 fixP->fx_addsy = section_symbol (absolute_section);
2710 #endif
2711 symbol_mark_used_in_reloc (fixP->fx_addsy);
2712 ++seg_reloc_count;
2716 if (!fixP->fx_done)
2718 #ifdef MD_APPLY_FIX3
2719 md_apply_fix3 (fixP, &add_number, this_segment_type);
2720 #else
2721 #ifdef BFD_ASSEMBLER
2722 md_apply_fix (fixP, &add_number);
2723 #else
2724 md_apply_fix (fixP, add_number);
2725 #endif
2726 #endif
2728 #ifndef TC_HANDLES_FX_DONE
2729 /* If the tc-* files haven't been converted, assume it's handling
2730 it the old way, where a null fx_addsy means that the fix has
2731 been applied completely, and no further work is needed. */
2732 if (fixP->fx_addsy == 0 && fixP->fx_pcrel == 0)
2733 fixP->fx_done = 1;
2734 #endif
2737 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && size > 0)
2739 if ((size_t) size < sizeof (valueT))
2741 valueT mask;
2743 mask = 0;
2744 mask--; /* set all bits to one */
2745 mask <<= size * 8 - (fixP->fx_signed ? 1 : 0);
2746 if ((add_number & mask) != 0 && (add_number & mask) != mask)
2748 char buf[50], buf2[50];
2749 sprint_value (buf, fragP->fr_address + where);
2750 if (add_number > 1000)
2751 sprint_value (buf2, add_number);
2752 else
2753 sprintf (buf2, "%ld", (long) add_number);
2754 as_bad_where (fixP->fx_file, fixP->fx_line,
2755 _("Value of %s too large for field of %d bytes at %s"),
2756 buf2, size, buf);
2757 } /* generic error checking */
2759 #ifdef WARN_SIGNED_OVERFLOW_WORD
2760 /* Warn if a .word value is too large when treated as a signed
2761 number. We already know it is not too negative. This is to
2762 catch over-large switches generated by gcc on the 68k. */
2763 if (!flag_signed_overflow_ok
2764 && size == 2
2765 && add_number > 0x7fff)
2766 as_bad_where (fixP->fx_file, fixP->fx_line,
2767 _("Signed .word overflow; switch may be too large; %ld at 0x%lx"),
2768 (long) add_number,
2769 (unsigned long) (fragP->fr_address + where));
2770 #endif
2771 } /* not a bit fix */
2773 #ifdef TC_VALIDATE_FIX
2774 skip: ATTRIBUTE_UNUSED_LABEL
2776 #endif
2777 #ifdef DEBUG5
2778 fprintf (stderr, "result:\n");
2779 print_fixup (fixP);
2780 #endif
2781 } /* For each fixS in this segment. */
2783 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2784 return seg_reloc_count;
2787 #endif /* defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS)) */
2789 void
2790 number_to_chars_bigendian (buf, val, n)
2791 char *buf;
2792 valueT val;
2793 int n;
2795 if ((size_t) n > sizeof (val) || n <= 0)
2796 abort ();
2797 while (n--)
2799 buf[n] = val & 0xff;
2800 val >>= 8;
2804 void
2805 number_to_chars_littleendian (buf, val, n)
2806 char *buf;
2807 valueT val;
2808 int n;
2810 if ((size_t) n > sizeof (val) || n <= 0)
2811 abort ();
2812 while (n--)
2814 *buf++ = val & 0xff;
2815 val >>= 8;
2819 void
2820 write_print_statistics (file)
2821 FILE *file;
2823 fprintf (file, "fixups: %d\n", n_fixups);
2826 /* for debugging */
2827 extern int indent_level;
2829 void
2830 print_fixup (fixp)
2831 fixS *fixp;
2833 indent_level = 1;
2834 fprintf (stderr, "fix %lx %s:%d", (long) fixp, fixp->fx_file, fixp->fx_line);
2835 if (fixp->fx_pcrel)
2836 fprintf (stderr, " pcrel");
2837 if (fixp->fx_pcrel_adjust)
2838 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2839 if (fixp->fx_im_disp)
2841 #ifdef TC_NS32K
2842 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2843 #else
2844 fprintf (stderr, " im_disp");
2845 #endif
2847 if (fixp->fx_tcbit)
2848 fprintf (stderr, " tcbit");
2849 if (fixp->fx_done)
2850 fprintf (stderr, " done");
2851 fprintf (stderr, "\n size=%d frag=%lx where=%ld offset=%lx addnumber=%lx",
2852 fixp->fx_size, (long) fixp->fx_frag, (long) fixp->fx_where,
2853 (long) fixp->fx_offset, (long) fixp->fx_addnumber);
2854 #ifdef BFD_ASSEMBLER
2855 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2856 fixp->fx_r_type);
2857 #else
2858 #ifdef NEED_FX_R_TYPE
2859 fprintf (stderr, " r_type=%d", fixp->fx_r_type);
2860 #endif
2861 #endif
2862 if (fixp->fx_addsy)
2864 fprintf (stderr, "\n +<");
2865 print_symbol_value_1 (stderr, fixp->fx_addsy);
2866 fprintf (stderr, ">");
2868 if (fixp->fx_subsy)
2870 fprintf (stderr, "\n -<");
2871 print_symbol_value_1 (stderr, fixp->fx_subsy);
2872 fprintf (stderr, ">");
2874 fprintf (stderr, "\n");
2875 #ifdef TC_FIX_DATA_PRINT
2876 TC_FIX_DATA_PRINT (stderr, fixp);
2877 #endif
2880 /* end of write.c */