1999-05-28 Martin Dorey <mdorey@madge.com>
[binutils.git] / gas / write.c
blob13f78b9ebe8ac3740c494608f2d4e65f869c9c99
1 /* write.c - emit .o file
2 Copyright (C) 1986, 87, 90, 91, 92, 93, 94, 95, 96, 97, 1998
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;
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; /* unused */
437 segT section;
438 PTR xxx; /* 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 (_("attempt to .org/.space backwards? (%ld)"),
502 (long) fragP->fr_offset);
504 fragP->fr_type = rs_fill;
505 break;
507 case rs_fill:
508 break;
510 case rs_leb128:
512 valueT value = S_GET_VALUE (fragP->fr_symbol);
513 int size;
515 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
516 fragP->fr_subtype);
518 fragP->fr_fix += size;
519 fragP->fr_type = rs_fill;
520 fragP->fr_var = 0;
521 fragP->fr_offset = 0;
522 fragP->fr_symbol = NULL;
524 break;
526 case rs_cfa:
527 eh_frame_convert_frag (fragP);
528 break;
530 case rs_machine_dependent:
531 #ifdef BFD_ASSEMBLER
532 md_convert_frag (stdoutput, sec, fragP);
533 #else
534 md_convert_frag (headersP, sec, fragP);
535 #endif
537 assert (fragP->fr_next == NULL
538 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
539 == fragP->fr_fix));
542 * After md_convert_frag, we make the frag into a ".space 0".
543 * Md_convert_frag() should set up any fixSs and constants
544 * required.
546 frag_wane (fragP);
547 break;
549 #ifndef WORKING_DOT_WORD
550 case rs_broken_word:
552 struct broken_word *lie;
554 if (fragP->fr_subtype)
556 fragP->fr_fix += md_short_jump_size;
557 for (lie = (struct broken_word *) (fragP->fr_symbol);
558 lie && lie->dispfrag == fragP;
559 lie = lie->next_broken_word)
560 if (lie->added == 1)
561 fragP->fr_fix += md_long_jump_size;
563 frag_wane (fragP);
565 break;
566 #endif
568 default:
569 BAD_CASE (fragP->fr_type);
570 break;
574 #endif /* defined (BFD_ASSEMBLER) || !defined (BFD) */
576 #ifdef BFD_ASSEMBLER
577 static void
578 relax_and_size_seg (abfd, sec, xxx)
579 bfd *abfd;
580 asection *sec;
581 PTR xxx;
583 flagword flags;
584 fragS *fragp;
585 segment_info_type *seginfo;
586 int x;
587 valueT size, newsize;
589 subseg_change (sec, 0);
591 flags = bfd_get_section_flags (abfd, sec);
593 seginfo = seg_info (sec);
594 if (seginfo && seginfo->frchainP)
596 relax_segment (seginfo->frchainP->frch_root, sec);
597 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
598 cvt_frag_to_fill (sec, fragp);
599 for (fragp = seginfo->frchainP->frch_root;
600 fragp->fr_next;
601 fragp = fragp->fr_next)
602 /* walk to last elt */;
603 size = fragp->fr_address + fragp->fr_fix;
605 else
606 size = 0;
608 if (size > 0 && ! seginfo->bss)
609 flags |= SEC_HAS_CONTENTS;
611 /* @@ This is just an approximation. */
612 if (seginfo && seginfo->fix_root)
613 flags |= SEC_RELOC;
614 else
615 flags &= ~SEC_RELOC;
616 x = bfd_set_section_flags (abfd, sec, flags);
617 assert (x == true);
619 newsize = md_section_align (sec, size);
620 x = bfd_set_section_size (abfd, sec, newsize);
621 assert (x == true);
623 /* If the size had to be rounded up, add some padding in the last
624 non-empty frag. */
625 assert (newsize >= size);
626 if (size != newsize)
628 fragS *last = seginfo->frchainP->frch_last;
629 fragp = seginfo->frchainP->frch_root;
630 while (fragp->fr_next != last)
631 fragp = fragp->fr_next;
632 last->fr_address = size;
633 fragp->fr_offset += newsize - size;
636 #ifdef tc_frob_section
637 tc_frob_section (sec);
638 #endif
639 #ifdef obj_frob_section
640 obj_frob_section (sec);
641 #endif
644 #ifdef DEBUG2
645 static void
646 dump_section_relocs (abfd, sec, stream_)
647 bfd *abfd;
648 asection *sec;
649 char *stream_;
651 FILE *stream = (FILE *) stream_;
652 segment_info_type *seginfo = seg_info (sec);
653 fixS *fixp = seginfo->fix_root;
655 if (!fixp)
656 return;
658 fprintf (stream, "sec %s relocs:\n", sec->name);
659 while (fixp)
661 symbolS *s = fixp->fx_addsy;
662 if (s)
664 fprintf (stream, " %08x: %s(%s", fixp, S_GET_NAME (s),
665 s->bsym->section->name);
666 if (s->bsym->flags & BSF_SECTION_SYM)
668 fprintf (stream, " section sym");
669 if (S_GET_VALUE (s))
670 fprintf (stream, "+%x", S_GET_VALUE (s));
672 else
673 fprintf (stream, "+%x", S_GET_VALUE (s));
674 fprintf (stream, ")+%x\n", fixp->fx_offset);
676 else
677 fprintf (stream, " %08x: type %d no sym\n", fixp, fixp->fx_r_type);
678 fixp = fixp->fx_next;
681 #else
682 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
683 #endif
685 #ifndef EMIT_SECTION_SYMBOLS
686 #define EMIT_SECTION_SYMBOLS 1
687 #endif
689 static void
690 adjust_reloc_syms (abfd, sec, xxx)
691 bfd *abfd;
692 asection *sec;
693 PTR xxx;
695 segment_info_type *seginfo = seg_info (sec);
696 fixS *fixp;
698 if (seginfo == NULL)
699 return;
701 dump_section_relocs (abfd, sec, stderr);
703 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
704 if (fixp->fx_done)
705 /* ignore it */;
706 else if (fixp->fx_addsy)
708 symbolS *sym;
709 asection *symsec;
711 #ifdef DEBUG5
712 fprintf (stderr, "\n\nadjusting fixup:\n");
713 print_fixup (fixp);
714 #endif
716 sym = fixp->fx_addsy;
718 /* All symbols should have already been resolved at this
719 point. It is possible to see unresolved expression
720 symbols, though, since they are not in the regular symbol
721 table. */
722 if (sym != NULL && ! sym->sy_resolved)
723 resolve_symbol_value (sym, 1);
725 if (fixp->fx_subsy != NULL && ! fixp->fx_subsy->sy_resolved)
726 resolve_symbol_value (fixp->fx_subsy, 1);
728 /* If this symbol is equated to an undefined symbol, convert
729 the fixup to being against that symbol. */
730 if (sym != NULL && sym->sy_value.X_op == O_symbol
731 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
733 fixp->fx_offset += sym->sy_value.X_add_number;
734 sym = sym->sy_value.X_add_symbol;
735 fixp->fx_addsy = sym;
738 if (sym != NULL && sym->sy_mri_common)
740 /* These symbols are handled specially in fixup_segment. */
741 goto done;
744 symsec = S_GET_SEGMENT (sym);
746 if (symsec == NULL)
747 abort ();
749 if (bfd_is_abs_section (symsec))
751 /* The fixup_segment routine will not use this symbol in a
752 relocation unless TC_FORCE_RELOCATION returns 1. */
753 if (TC_FORCE_RELOCATION (fixp))
755 fixp->fx_addsy->sy_used_in_reloc = 1;
756 #ifdef UNDEFINED_DIFFERENCE_OK
757 if (fixp->fx_subsy != NULL)
758 fixp->fx_subsy->sy_used_in_reloc = 1;
759 #endif
761 goto done;
764 /* If it's one of these sections, assume the symbol is
765 definitely going to be output. The code in
766 md_estimate_size_before_relax in tc-mips.c uses this test
767 as well, so if you change this code you should look at that
768 code. */
769 if (bfd_is_und_section (symsec)
770 || bfd_is_com_section (symsec))
772 fixp->fx_addsy->sy_used_in_reloc = 1;
773 #ifdef UNDEFINED_DIFFERENCE_OK
774 /* We have the difference of an undefined symbol and some
775 other symbol. Make sure to mark the other symbol as used
776 in a relocation so that it will always be output. */
777 if (fixp->fx_subsy)
778 fixp->fx_subsy->sy_used_in_reloc = 1;
779 #endif
780 goto done;
783 /* Don't try to reduce relocs which refer to .linkonce
784 sections. It can lead to confusion when a debugging
785 section refers to a .linkonce section. I hope this will
786 always be correct. */
787 if (symsec != sec)
789 boolean linkonce;
791 linkonce = false;
792 #ifdef BFD_ASSEMBLER
793 if ((bfd_get_section_flags (stdoutput, symsec) & SEC_LINK_ONCE)
794 != 0)
795 linkonce = true;
796 #endif
797 #ifdef OBJ_ELF
798 /* The GNU toolchain uses an extension for ELF: a section
799 beginning with the magic string .gnu.linkonce is a
800 linkonce section. */
801 if (strncmp (segment_name (symsec), ".gnu.linkonce",
802 sizeof ".gnu.linkonce" - 1) == 0)
803 linkonce = true;
804 #endif
806 if (linkonce)
808 fixp->fx_addsy->sy_used_in_reloc = 1;
809 #ifdef UNDEFINED_DIFFERENCE_OK
810 if (fixp->fx_subsy != NULL)
811 fixp->fx_subsy->sy_used_in_reloc = 1;
812 #endif
813 goto done;
817 /* Since we're reducing to section symbols, don't attempt to reduce
818 anything that's already using one. */
819 if (sym->bsym->flags & BSF_SECTION_SYM)
821 fixp->fx_addsy->sy_used_in_reloc = 1;
822 goto done;
825 #ifdef BFD_ASSEMBLER
826 /* We can never adjust a reloc against a weak symbol. If we
827 did, and the weak symbol was overridden by a real symbol
828 somewhere else, then our relocation would be pointing at
829 the wrong area of memory. */
830 if (S_IS_WEAK (sym))
832 fixp->fx_addsy->sy_used_in_reloc = 1;
833 goto done;
835 #endif
837 /* Is there some other reason we can't adjust this one? (E.g.,
838 call/bal links in i960-bout symbols.) */
839 #ifdef obj_fix_adjustable
840 if (! obj_fix_adjustable (fixp))
842 fixp->fx_addsy->sy_used_in_reloc = 1;
843 goto done;
845 #endif
847 /* Is there some other (target cpu dependent) reason we can't adjust
848 this one? (E.g. relocations involving function addresses on
849 the PA. */
850 #ifdef tc_fix_adjustable
851 if (! tc_fix_adjustable (fixp))
853 fixp->fx_addsy->sy_used_in_reloc = 1;
854 goto done;
856 #endif
858 /* If the section symbol isn't going to be output, the relocs
859 at least should still work. If not, figure out what to do
860 when we run into that case.
862 We refetch the segment when calling section_symbol, rather
863 than using symsec, because S_GET_VALUE may wind up changing
864 the section when it calls resolve_symbol_value. */
865 fixp->fx_offset += S_GET_VALUE (sym);
866 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
867 fixp->fx_addsy->sy_used_in_reloc = 1;
869 done:
872 #if 1/*def RELOC_REQUIRES_SYMBOL*/
873 else
875 /* There was no symbol required by this relocation. However,
876 BFD doesn't really handle relocations without symbols well.
877 (At least, the COFF support doesn't.) So for now we fake up
878 a local symbol in the absolute section. */
880 fixp->fx_addsy = section_symbol (absolute_section);
881 /* fixp->fx_addsy->sy_used_in_reloc = 1; */
883 #endif
885 dump_section_relocs (abfd, sec, stderr);
888 static void
889 write_relocs (abfd, sec, xxx)
890 bfd *abfd;
891 asection *sec;
892 PTR xxx;
894 segment_info_type *seginfo = seg_info (sec);
895 int i;
896 unsigned int n;
897 arelent **relocs;
898 fixS *fixp;
899 char *err;
901 /* If seginfo is NULL, we did not create this section; don't do
902 anything with it. */
903 if (seginfo == NULL)
904 return;
906 fixup_segment (seginfo->fix_root, sec);
908 n = 0;
909 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
910 n++;
912 #ifndef RELOC_EXPANSION_POSSIBLE
913 /* Set up reloc information as well. */
914 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
915 memset ((char*)relocs, 0, n * sizeof (arelent*));
917 i = 0;
918 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
920 arelent *reloc;
921 bfd_reloc_status_type s;
922 symbolS *sym;
924 if (fixp->fx_done)
926 n--;
927 continue;
930 /* If this is an undefined symbol which was equated to another
931 symbol, then use generate the reloc against the latter symbol
932 rather than the former. */
933 sym = fixp->fx_addsy;
934 while (sym->sy_value.X_op == O_symbol
935 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
937 symbolS *n;
939 /* We must avoid looping, as that can occur with a badly
940 written program. */
941 n = sym->sy_value.X_add_symbol;
942 if (n == sym)
943 break;
944 fixp->fx_offset += sym->sy_value.X_add_number;
945 sym = n;
947 fixp->fx_addsy = sym;
949 reloc = tc_gen_reloc (sec, fixp);
950 if (!reloc)
952 n--;
953 continue;
956 #if 0
957 /* This test is triggered inappropriately for the SH. */
958 if (fixp->fx_where + fixp->fx_size
959 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
960 abort ();
961 #endif
963 s = bfd_install_relocation (stdoutput, reloc,
964 fixp->fx_frag->fr_literal,
965 fixp->fx_frag->fr_address,
966 sec, &err);
967 switch (s)
969 case bfd_reloc_ok:
970 break;
971 case bfd_reloc_overflow:
972 as_bad_where (fixp->fx_file, fixp->fx_line, _("relocation overflow"));
973 break;
974 case bfd_reloc_outofrange:
975 as_bad_where (fixp->fx_file, fixp->fx_line, _("relocation out of range"));
976 break;
977 default:
978 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
979 fixp->fx_file, fixp->fx_line, s);
981 relocs[i++] = reloc;
983 #else
984 n = n * MAX_RELOC_EXPANSION;
985 /* Set up reloc information as well. */
986 relocs = (arelent **) xmalloc (n * sizeof (arelent *));
988 i = 0;
989 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
991 arelent **reloc;
992 char *data;
993 bfd_reloc_status_type s;
994 symbolS *sym;
995 int j;
997 if (fixp->fx_done)
999 n--;
1000 continue;
1003 /* If this is an undefined symbol which was equated to another
1004 symbol, then use generate the reloc against the latter symbol
1005 rather than the former. */
1006 sym = fixp->fx_addsy;
1007 while (sym->sy_value.X_op == O_symbol
1008 && (! S_IS_DEFINED (sym) || S_IS_COMMON (sym)))
1009 sym = sym->sy_value.X_add_symbol;
1010 fixp->fx_addsy = sym;
1012 reloc = tc_gen_reloc (sec, fixp);
1014 for (j = 0; reloc[j]; j++)
1016 relocs[i++] = reloc[j];
1017 assert(i <= n);
1019 data = fixp->fx_frag->fr_literal + fixp->fx_where;
1020 if (fixp->fx_where + fixp->fx_size
1021 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
1022 as_bad_where (fixp->fx_file, fixp->fx_line,
1023 _("internal error: fixup not contained within frag"));
1024 for (j = 0; reloc[j]; j++)
1026 s = bfd_install_relocation (stdoutput, reloc[j],
1027 fixp->fx_frag->fr_literal,
1028 fixp->fx_frag->fr_address,
1029 sec, &err);
1030 switch (s)
1032 case bfd_reloc_ok:
1033 break;
1034 case bfd_reloc_overflow:
1035 as_bad_where (fixp->fx_file, fixp->fx_line,
1036 _("relocation overflow"));
1037 break;
1038 default:
1039 as_fatal (_("%s:%u: bad return from bfd_install_relocation"),
1040 fixp->fx_file, fixp->fx_line);
1044 n = i;
1045 #endif
1047 #ifdef DEBUG4
1049 int i, j, nsyms;
1050 asymbol **sympp;
1051 sympp = bfd_get_outsymbols (stdoutput);
1052 nsyms = bfd_get_symcount (stdoutput);
1053 for (i = 0; i < n; i++)
1054 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1056 for (j = 0; j < nsyms; j++)
1057 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1058 break;
1059 if (j == nsyms)
1060 abort ();
1063 #endif
1065 if (n)
1066 bfd_set_reloc (stdoutput, sec, relocs, n);
1067 else
1068 bfd_set_section_flags (abfd, sec,
1069 (bfd_get_section_flags (abfd, sec)
1070 & (flagword) ~SEC_RELOC));
1072 #ifdef DEBUG3
1074 int i;
1075 arelent *r;
1076 asymbol *s;
1077 fprintf (stderr, "relocs for sec %s\n", sec->name);
1078 for (i = 0; i < n; i++)
1080 r = relocs[i];
1081 s = *r->sym_ptr_ptr;
1082 fprintf (stderr, " reloc %2d @%08x off %4x : sym %-10s addend %x\n",
1083 i, r, r->address, s->name, r->addend);
1086 #endif
1089 static void
1090 write_contents (abfd, sec, xxx)
1091 bfd *abfd;
1092 asection *sec;
1093 PTR xxx;
1095 segment_info_type *seginfo = seg_info (sec);
1096 unsigned long offset = 0;
1097 fragS *f;
1099 /* Write out the frags. */
1100 if (seginfo == NULL
1101 || ! (bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1102 return;
1104 for (f = seginfo->frchainP->frch_root;
1106 f = f->fr_next)
1108 int x;
1109 unsigned long fill_size;
1110 char *fill_literal;
1111 long count;
1113 assert (f->fr_type == rs_fill);
1114 if (f->fr_fix)
1116 x = bfd_set_section_contents (stdoutput, sec,
1117 f->fr_literal, (file_ptr) offset,
1118 (bfd_size_type) f->fr_fix);
1119 if (x == false)
1121 bfd_perror (stdoutput->filename);
1122 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1123 exit (EXIT_FAILURE);
1125 offset += f->fr_fix;
1127 fill_literal = f->fr_literal + f->fr_fix;
1128 fill_size = f->fr_var;
1129 count = f->fr_offset;
1130 assert (count >= 0);
1131 if (fill_size && count)
1133 char buf[256];
1134 if (fill_size > sizeof(buf))
1136 /* Do it the old way. Can this ever happen? */
1137 while (count--)
1139 x = bfd_set_section_contents (stdoutput, sec,
1140 fill_literal,
1141 (file_ptr) offset,
1142 (bfd_size_type) fill_size);
1143 if (x == false)
1145 bfd_perror (stdoutput->filename);
1146 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1147 exit (EXIT_FAILURE);
1149 offset += fill_size;
1152 else
1154 /* Build a buffer full of fill objects and output it as
1155 often as necessary. This saves on the overhead of
1156 potentially lots of bfd_set_section_contents calls. */
1157 int n_per_buf, i;
1158 if (fill_size == 1)
1160 n_per_buf = sizeof (buf);
1161 memset (buf, *fill_literal, n_per_buf);
1163 else
1165 char *bufp;
1166 n_per_buf = sizeof(buf)/fill_size;
1167 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1168 memcpy(bufp, fill_literal, fill_size);
1170 for (; count > 0; count -= n_per_buf)
1172 n_per_buf = n_per_buf > count ? count : n_per_buf;
1173 x = bfd_set_section_contents (stdoutput, sec,
1174 buf, (file_ptr) offset,
1175 (bfd_size_type) n_per_buf * fill_size);
1176 if (x != true)
1177 as_fatal (_("Cannot write to output file."));
1178 offset += n_per_buf * fill_size;
1184 #endif
1186 #if defined(BFD_ASSEMBLER) || (!defined (BFD) && !defined(OBJ_AOUT))
1187 static void
1188 merge_data_into_text ()
1190 #if defined(BFD_ASSEMBLER) || defined(MANY_SEGMENTS)
1191 seg_info (text_section)->frchainP->frch_last->fr_next =
1192 seg_info (data_section)->frchainP->frch_root;
1193 seg_info (text_section)->frchainP->frch_last =
1194 seg_info (data_section)->frchainP->frch_last;
1195 seg_info (data_section)->frchainP = 0;
1196 #else
1197 fixS *tmp;
1199 text_last_frag->fr_next = data_frag_root;
1200 text_last_frag = data_last_frag;
1201 data_last_frag = NULL;
1202 data_frag_root = NULL;
1203 if (text_fix_root)
1205 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
1206 tmp->fx_next = data_fix_root;
1207 text_fix_tail = data_fix_tail;
1209 else
1210 text_fix_root = data_fix_root;
1211 data_fix_root = NULL;
1212 #endif
1214 #endif /* BFD_ASSEMBLER || (! BFD && ! OBJ_AOUT) */
1216 #if !defined (BFD_ASSEMBLER) && !defined (BFD)
1217 static void
1218 relax_and_size_all_segments ()
1220 fragS *fragP;
1222 relax_segment (text_frag_root, SEG_TEXT);
1223 relax_segment (data_frag_root, SEG_DATA);
1224 relax_segment (bss_frag_root, SEG_BSS);
1226 * Now the addresses of frags are correct within the segment.
1229 know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
1230 H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
1231 text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
1234 * Join the 2 segments into 1 huge segment.
1235 * To do this, re-compute every rn_address in the SEG_DATA frags.
1236 * Then join the data frags after the text frags.
1238 * Determine a_data [length of data segment].
1240 if (data_frag_root)
1242 register relax_addressT slide;
1244 know ((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
1246 H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
1247 data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
1248 slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
1249 #ifdef OBJ_BOUT
1250 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
1251 /* For b.out: If the data section has a strict alignment
1252 requirement, its load address in the .o file will be
1253 rounded up from the size of the text section. These
1254 two values are *not* the same! Similarly for the bss
1255 section.... */
1256 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
1257 #endif
1259 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
1261 fragP->fr_address += slide;
1262 } /* for each data frag */
1264 know (text_last_frag != 0);
1265 text_last_frag->fr_next = data_frag_root;
1267 else
1269 H_SET_DATA_SIZE (&headers, 0);
1272 #ifdef OBJ_BOUT
1273 /* See above comments on b.out data section address. */
1275 long bss_vma;
1276 if (data_last_frag == 0)
1277 bss_vma = H_GET_TEXT_SIZE (&headers);
1278 else
1279 bss_vma = data_last_frag->fr_address;
1280 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
1281 bss_address_frag.fr_address = bss_vma;
1283 #else /* ! OBJ_BOUT */
1284 bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
1285 H_GET_DATA_SIZE (&headers));
1287 #endif /* ! OBJ_BOUT */
1289 /* Slide all the frags */
1290 if (bss_frag_root)
1292 relax_addressT slide = bss_address_frag.fr_address;
1294 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
1296 fragP->fr_address += slide;
1297 } /* for each bss frag */
1300 if (bss_last_frag)
1301 H_SET_BSS_SIZE (&headers,
1302 bss_last_frag->fr_address - bss_frag_root->fr_address);
1303 else
1304 H_SET_BSS_SIZE (&headers, 0);
1306 #endif /* ! BFD_ASSEMBLER && ! BFD */
1308 #if defined (BFD_ASSEMBLER) || !defined (BFD)
1310 #ifdef BFD_ASSEMBLER
1311 static void
1312 set_symtab ()
1314 int nsyms;
1315 asymbol **asympp;
1316 symbolS *symp;
1317 boolean result;
1318 extern PTR bfd_alloc PARAMS ((bfd *, size_t));
1320 /* Count symbols. We can't rely on a count made by the loop in
1321 write_object_file, because *_frob_file may add a new symbol or
1322 two. */
1323 nsyms = 0;
1324 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1325 nsyms++;
1327 if (nsyms)
1329 int i;
1331 asympp = (asymbol **) bfd_alloc (stdoutput,
1332 nsyms * sizeof (asymbol *));
1333 symp = symbol_rootP;
1334 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1336 asympp[i] = symp->bsym;
1337 symp->written = 1;
1340 else
1341 asympp = 0;
1342 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1343 assert (result == true);
1344 symbol_table_frozen = 1;
1346 #endif
1348 /* Finish the subsegments. After every sub-segment, we fake an
1349 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1350 ".fill 0" because that is the kind of frag that requires least
1351 thought. ".align" frags like to have a following frag since that
1352 makes calculating their intended length trivial. */
1354 #ifndef SUB_SEGMENT_ALIGN
1355 #ifdef BFD_ASSEMBLER
1356 #define SUB_SEGMENT_ALIGN(SEG) (0)
1357 #else
1358 #define SUB_SEGMENT_ALIGN(SEG) (2)
1359 #endif
1360 #endif
1362 void
1363 subsegs_finish ()
1365 struct frchain *frchainP;
1367 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
1369 subseg_set (frchainP->frch_seg, frchainP->frch_subseg);
1371 /* This now gets called even if we had errors. In that case,
1372 any alignment is meaningless, and, moreover, will look weird
1373 if we are generating a listing. */
1374 frag_align (had_errors () ? 0 : SUB_SEGMENT_ALIGN (now_seg),
1375 NOP_OPCODE, 0);
1377 /* frag_align will have left a new frag.
1378 Use this last frag for an empty ".fill".
1380 For this segment ...
1381 Create a last frag. Do not leave a "being filled in frag". */
1383 frag_wane (frag_now);
1384 frag_now->fr_fix = 0;
1385 know (frag_now->fr_next == NULL);
1389 /* Write the object file. */
1391 void
1392 write_object_file ()
1394 #if ! defined (BFD_ASSEMBLER) || ! defined (WORKING_DOT_WORD)
1395 fragS *fragP; /* Track along all frags. */
1396 #endif
1398 /* Do we really want to write it? */
1400 int n_warns, n_errs;
1401 n_warns = had_warnings ();
1402 n_errs = had_errors ();
1403 /* The -Z flag indicates that an object file should be generated,
1404 regardless of warnings and errors. */
1405 if (flag_always_generate_output)
1407 if (n_warns || n_errs)
1408 as_warn (_("%d error%s, %d warning%s, generating bad object file.\n"),
1409 n_errs, n_errs == 1 ? "" : "s",
1410 n_warns, n_warns == 1 ? "" : "s");
1412 else
1414 if (n_errs)
1415 as_fatal (_("%d error%s, %d warning%s, no object file generated.\n"),
1416 n_errs, n_errs == 1 ? "" : "s",
1417 n_warns, n_warns == 1 ? "" : "s");
1421 #ifdef OBJ_VMS
1422 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1423 a routine to check for the definition of the procedure "_main",
1424 and if so -- fix it up so that it can be program entry point. */
1425 vms_check_for_main ();
1426 #endif /* OBJ_VMS */
1428 /* From now on, we don't care about sub-segments. Build one frag chain
1429 for each segment. Linked thru fr_next. */
1431 #ifdef BFD_ASSEMBLER
1432 /* Remove the sections created by gas for its own purposes. */
1434 asection **seclist, *sec;
1435 int i;
1437 seclist = &stdoutput->sections;
1438 while (seclist && *seclist)
1440 sec = *seclist;
1441 while (sec == reg_section || sec == expr_section)
1443 sec = sec->next;
1444 *seclist = sec;
1445 stdoutput->section_count--;
1446 if (!sec)
1447 break;
1449 if (*seclist)
1450 seclist = &(*seclist)->next;
1452 i = 0;
1453 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1456 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1457 #else
1458 remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
1459 remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
1460 remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
1461 #endif
1463 /* We have two segments. If user gave -R flag, then we must put the
1464 data frags into the text segment. Do this before relaxing so
1465 we know to take advantage of -R and make shorter addresses. */
1466 #if !defined (OBJ_AOUT) || defined (BFD_ASSEMBLER)
1467 if (flag_readonly_data_in_text)
1469 merge_data_into_text ();
1471 #endif
1473 #ifdef BFD_ASSEMBLER
1474 bfd_map_over_sections (stdoutput, relax_and_size_seg, (char *) 0);
1475 #else
1476 relax_and_size_all_segments ();
1477 #endif /* BFD_ASSEMBLER */
1479 #ifndef BFD_ASSEMBLER
1482 * Crawl the symbol chain.
1484 * For each symbol whose value depends on a frag, take the address of
1485 * that frag and subsume it into the value of the symbol.
1486 * After this, there is just one way to lookup a symbol value.
1487 * Values are left in their final state for object file emission.
1488 * We adjust the values of 'L' local symbols, even if we do
1489 * not intend to emit them to the object file, because their values
1490 * are needed for fix-ups.
1492 * Unless we saw a -L flag, remove all symbols that begin with 'L'
1493 * from the symbol chain. (They are still pointed to by the fixes.)
1495 * Count the remaining symbols.
1496 * Assign a symbol number to each symbol.
1497 * Count the number of string-table chars we will emit.
1498 * Put this info into the headers as appropriate.
1501 know (zero_address_frag.fr_address == 0);
1502 string_byte_count = sizeof (string_byte_count);
1504 obj_crawl_symbol_chain (&headers);
1506 if (string_byte_count == sizeof (string_byte_count))
1507 string_byte_count = 0;
1509 H_SET_STRING_SIZE (&headers, string_byte_count);
1512 * Addresses of frags now reflect addresses we use in the object file.
1513 * Symbol values are correct.
1514 * Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
1515 * Also converting any machine-dependent frags using md_convert_frag();
1517 subseg_change (SEG_TEXT, 0);
1519 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1521 /* At this point we have linked all the frags into a single
1522 chain. However, cvt_frag_to_fill may call md_convert_frag
1523 which may call fix_new. We need to ensure that fix_new adds
1524 the fixup to the right section. */
1525 if (fragP == data_frag_root)
1526 subseg_change (SEG_DATA, 0);
1528 cvt_frag_to_fill (&headers, SEG_TEXT, fragP);
1530 /* Some assert macros don't work with # directives mixed in. */
1531 #ifndef NDEBUG
1532 if (!(fragP->fr_next == NULL
1533 #ifdef OBJ_BOUT
1534 || fragP->fr_next == data_frag_root
1535 #endif
1536 || ((fragP->fr_next->fr_address - fragP->fr_address)
1537 == (fragP->fr_fix + fragP->fr_offset * fragP->fr_var))))
1538 abort ();
1539 #endif
1541 #endif /* ! BFD_ASSEMBLER */
1543 #ifndef WORKING_DOT_WORD
1545 struct broken_word *lie;
1546 struct broken_word **prevP;
1548 prevP = &broken_words;
1549 for (lie = broken_words; lie; lie = lie->next_broken_word)
1550 if (!lie->added)
1552 expressionS exp;
1554 subseg_change (lie->seg, lie->subseg);
1555 exp.X_op = O_subtract;
1556 exp.X_add_symbol = lie->add;
1557 exp.X_op_symbol = lie->sub;
1558 exp.X_add_number = lie->addnum;
1559 #ifdef BFD_ASSEMBLER
1560 #ifdef TC_CONS_FIX_NEW
1561 TC_CONS_FIX_NEW (lie->frag,
1562 lie->word_goes_here - lie->frag->fr_literal,
1563 2, &exp);
1564 #else
1565 fix_new_exp (lie->frag,
1566 lie->word_goes_here - lie->frag->fr_literal,
1567 2, &exp, 0, BFD_RELOC_16);
1568 #endif
1569 #else
1570 #if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
1571 fix_new_exp (lie->frag,
1572 lie->word_goes_here - lie->frag->fr_literal,
1573 2, &exp, 0, NO_RELOC);
1574 #else
1575 #ifdef TC_NS32K
1576 fix_new_ns32k_exp (lie->frag,
1577 lie->word_goes_here - lie->frag->fr_literal,
1578 2, &exp, 0, 0, 2, 0, 0);
1579 #else
1580 fix_new_exp (lie->frag,
1581 lie->word_goes_here - lie->frag->fr_literal,
1582 2, &exp, 0, 0);
1583 #endif /* TC_NS32K */
1584 #endif /* TC_SPARC|TC_A29K|NEED_FX_R_TYPE */
1585 #endif /* BFD_ASSEMBLER */
1586 *prevP = lie->next_broken_word;
1588 else
1589 prevP = &(lie->next_broken_word);
1591 for (lie = broken_words; lie;)
1593 struct broken_word *untruth;
1594 char *table_ptr;
1595 addressT table_addr;
1596 addressT from_addr, to_addr;
1597 int n, m;
1599 subseg_change (lie->seg, lie->subseg);
1600 fragP = lie->dispfrag;
1602 /* Find out how many broken_words go here. */
1603 n = 0;
1604 for (untruth = lie; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
1605 if (untruth->added == 1)
1606 n++;
1608 table_ptr = lie->dispfrag->fr_opcode;
1609 table_addr = lie->dispfrag->fr_address + (table_ptr - lie->dispfrag->fr_literal);
1610 /* Create the jump around the long jumps. This is a short
1611 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1612 from_addr = table_addr;
1613 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1614 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
1615 table_ptr += md_short_jump_size;
1616 table_addr += md_short_jump_size;
1618 for (m = 0; lie && lie->dispfrag == fragP; m++, lie = lie->next_broken_word)
1620 if (lie->added == 2)
1621 continue;
1622 /* Patch the jump table */
1623 /* This is the offset from ??? to table_ptr+0 */
1624 to_addr = table_addr - S_GET_VALUE (lie->sub);
1625 #ifdef BFD_ASSEMBLER
1626 to_addr -= lie->sub->sy_frag->fr_address;
1627 #endif
1628 md_number_to_chars (lie->word_goes_here, to_addr, 2);
1629 for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
1631 if (untruth->use_jump == lie)
1632 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
1635 /* Install the long jump */
1636 /* this is a long jump from table_ptr+0 to the final target */
1637 from_addr = table_addr;
1638 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1639 #ifdef BFD_ASSEMBLER
1640 to_addr += lie->add->sy_frag->fr_address;
1641 #endif
1642 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
1643 table_ptr += md_long_jump_size;
1644 table_addr += md_long_jump_size;
1648 #endif /* not WORKING_DOT_WORD */
1650 #ifndef BFD_ASSEMBLER
1651 #ifndef OBJ_VMS
1652 { /* not vms */
1653 char *the_object_file;
1654 long object_file_size;
1656 * Scan every FixS performing fixups. We had to wait until now to do
1657 * this because md_convert_frag() may have made some fixSs.
1659 int trsize, drsize;
1661 subseg_change (SEG_TEXT, 0);
1662 trsize = md_reloc_size * fixup_segment (text_fix_root, SEG_TEXT);
1663 subseg_change (SEG_DATA, 0);
1664 drsize = md_reloc_size * fixup_segment (data_fix_root, SEG_DATA);
1665 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
1667 /* FIXME move this stuff into the pre-write-hook */
1668 H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
1669 H_SET_ENTRY_POINT (&headers, 0);
1671 obj_pre_write_hook (&headers); /* extra coff stuff */
1673 object_file_size = H_GET_FILE_SIZE (&headers);
1674 next_object_file_charP = the_object_file = xmalloc (object_file_size);
1676 output_file_create (out_file_name);
1678 obj_header_append (&next_object_file_charP, &headers);
1680 know ((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE (&headers));
1683 * Emit code.
1685 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1687 register long count;
1688 register char *fill_literal;
1689 register long fill_size;
1691 PROGRESS (1);
1692 know (fragP->fr_type == rs_fill);
1693 append (&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
1694 fill_literal = fragP->fr_literal + fragP->fr_fix;
1695 fill_size = fragP->fr_var;
1696 know (fragP->fr_offset >= 0);
1698 for (count = fragP->fr_offset; count; count--)
1700 append (&next_object_file_charP, fill_literal, (unsigned long) fill_size);
1701 } /* for each */
1703 } /* for each code frag. */
1705 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers)));
1708 * Emit relocations.
1710 obj_emit_relocations (&next_object_file_charP, text_fix_root, (relax_addressT) 0);
1711 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)));
1712 #ifdef TC_I960
1713 /* Make addresses in data relocation directives relative to beginning of
1714 * first data fragment, not end of last text fragment: alignment of the
1715 * start of the data segment may place a gap between the segments.
1717 obj_emit_relocations (&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
1718 #else /* TC_I960 */
1719 obj_emit_relocations (&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
1720 #endif /* TC_I960 */
1722 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)));
1725 * Emit line number entries.
1727 OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
1728 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)));
1731 * Emit symbols.
1733 obj_emit_symbols (&next_object_file_charP, symbol_rootP);
1734 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)));
1737 * Emit strings.
1740 if (string_byte_count > 0)
1742 obj_emit_strings (&next_object_file_charP);
1743 } /* only if we have a string table */
1745 #ifdef BFD_HEADERS
1746 bfd_seek (stdoutput, 0, 0);
1747 bfd_write (the_object_file, 1, object_file_size, stdoutput);
1748 #else
1750 /* Write the data to the file */
1751 output_file_append (the_object_file, object_file_size, out_file_name);
1752 free (the_object_file);
1753 #endif
1754 } /* non vms output */
1755 #else /* OBJ_VMS */
1757 * Now do the VMS-dependent part of writing the object file
1759 vms_write_object_file (H_GET_TEXT_SIZE (&headers),
1760 H_GET_DATA_SIZE (&headers),
1761 H_GET_BSS_SIZE (&headers),
1762 text_frag_root, data_frag_root);
1763 #endif /* OBJ_VMS */
1764 #else /* BFD_ASSEMBLER */
1766 /* Resolve symbol values. This needs to be done before processing
1767 the relocations. */
1768 if (symbol_rootP)
1770 symbolS *symp;
1772 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1773 if (!symp->sy_resolved)
1774 resolve_symbol_value (symp, 1);
1777 PROGRESS (1);
1779 #ifdef tc_frob_file_before_adjust
1780 tc_frob_file_before_adjust ();
1781 #endif
1782 #ifdef obj_frob_file_before_adjust
1783 obj_frob_file_before_adjust ();
1784 #endif
1786 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *)0);
1788 /* Set up symbol table, and write it out. */
1789 if (symbol_rootP)
1791 symbolS *symp;
1793 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1795 int punt = 0;
1796 const char *name;
1798 if (symp->sy_mri_common)
1800 if (S_IS_EXTERNAL (symp))
1801 as_bad (_("%s: global symbols not supported in common sections"),
1802 S_GET_NAME (symp));
1803 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1804 continue;
1807 name = S_GET_NAME (symp);
1808 if (name)
1810 const char *name2 = decode_local_label_name ((char *)S_GET_NAME (symp));
1811 /* They only differ if `name' is a fb or dollar local
1812 label name. */
1813 if (name2 != name && ! S_IS_DEFINED (symp))
1814 as_bad (_("local label %s is not defined"), name2);
1817 /* Do it again, because adjust_reloc_syms might introduce
1818 more symbols. They'll probably only be section symbols,
1819 but they'll still need to have the values computed. */
1820 if (! symp->sy_resolved)
1822 if (symp->sy_value.X_op == O_constant)
1824 /* This is the normal case; skip the call. */
1825 S_SET_VALUE (symp,
1826 (S_GET_VALUE (symp)
1827 + symp->sy_frag->fr_address));
1828 symp->sy_resolved = 1;
1830 else
1831 resolve_symbol_value (symp, 1);
1834 /* Skip symbols which were equated to undefined or common
1835 symbols. */
1836 if (symp->sy_value.X_op == O_symbol
1837 && (! S_IS_DEFINED (symp) || S_IS_COMMON (symp)))
1839 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1840 continue;
1843 /* So far, common symbols have been treated like undefined symbols.
1844 Put them in the common section now. */
1845 if (S_IS_DEFINED (symp) == 0
1846 && S_GET_VALUE (symp) != 0)
1847 S_SET_SEGMENT (symp, bfd_com_section_ptr);
1848 #if 0
1849 printf ("symbol `%s'\n\t@%x: value=%d flags=%x seg=%s\n",
1850 S_GET_NAME (symp), symp,
1851 S_GET_VALUE (symp),
1852 symp->bsym->flags,
1853 segment_name (symp->bsym->section));
1854 #endif
1856 #ifdef obj_frob_symbol
1857 obj_frob_symbol (symp, punt);
1858 #endif
1859 #ifdef tc_frob_symbol
1860 if (! punt || symp->sy_used_in_reloc)
1861 tc_frob_symbol (symp, punt);
1862 #endif
1864 /* If we don't want to keep this symbol, splice it out of
1865 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1866 want section symbols. Otherwise, we skip local symbols
1867 and symbols that the frob_symbol macros told us to punt,
1868 but we keep such symbols if they are used in relocs. */
1869 if ((! EMIT_SECTION_SYMBOLS
1870 && (symp->bsym->flags & BSF_SECTION_SYM) != 0)
1871 /* Note that S_IS_EXTERN and S_IS_LOCAL are not always
1872 opposites. Sometimes the former checks flags and the
1873 latter examines the name... */
1874 || (!S_IS_EXTERN (symp)
1875 && (S_IS_LOCAL (symp) || punt)
1876 && ! symp->sy_used_in_reloc))
1878 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1879 /* After symbol_remove, symbol_next(symp) still returns
1880 the one that came after it in the chain. So we don't
1881 need to do any extra cleanup work here. */
1883 continue;
1886 /* Make sure we really got a value for the symbol. */
1887 if (! symp->sy_resolved)
1889 as_bad (_("can't resolve value for symbol \"%s\""),
1890 S_GET_NAME (symp));
1891 symp->sy_resolved = 1;
1894 /* Set the value into the BFD symbol. Up til now the value
1895 has only been kept in the gas symbolS struct. */
1896 symp->bsym->value = S_GET_VALUE (symp);
1900 PROGRESS (1);
1902 /* Now do any format-specific adjustments to the symbol table, such
1903 as adding file symbols. */
1904 #ifdef tc_adjust_symtab
1905 tc_adjust_symtab ();
1906 #endif
1907 #ifdef obj_adjust_symtab
1908 obj_adjust_symtab ();
1909 #endif
1911 /* Now that all the sizes are known, and contents correct, we can
1912 start writing to the file. */
1913 set_symtab ();
1915 /* If *_frob_file changes the symbol value at this point, it is
1916 responsible for moving the changed value into symp->bsym->value
1917 as well. Hopefully all symbol value changing can be done in
1918 *_frob_symbol. */
1919 #ifdef tc_frob_file
1920 tc_frob_file ();
1921 #endif
1922 #ifdef obj_frob_file
1923 obj_frob_file ();
1924 #endif
1926 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
1928 #ifdef tc_frob_file_after_relocs
1929 tc_frob_file_after_relocs ();
1930 #endif
1931 #ifdef obj_frob_file_after_relocs
1932 obj_frob_file_after_relocs ();
1933 #endif
1935 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
1936 #endif /* BFD_ASSEMBLER */
1938 #endif /* ! BFD */
1941 * relax_segment()
1943 * Now we have a segment, not a crowd of sub-segments, we can make fr_address
1944 * values.
1946 * Relax the frags.
1948 * After this, all frags in this segment have addresses that are correct
1949 * within the segment. Since segments live in different file addresses,
1950 * these frag addresses may not be the same as final object-file addresses.
1953 #ifdef TC_GENERIC_RELAX_TABLE
1955 static int is_dnrange PARAMS ((fragS *, fragS *));
1957 /* Subroutines of relax_segment. */
1958 static int
1959 is_dnrange (f1, f2)
1960 fragS *f1;
1961 fragS *f2;
1963 for (; f1; f1 = f1->fr_next)
1964 if (f1->fr_next == f2)
1965 return 1;
1966 return 0;
1969 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
1971 long
1972 relax_frag (fragP, stretch)
1973 fragS *fragP;
1974 long stretch;
1976 const relax_typeS *this_type;
1977 const relax_typeS *start_type;
1978 relax_substateT next_state;
1979 relax_substateT this_state;
1980 long aim, target, growth;
1981 symbolS *symbolP = fragP->fr_symbol;
1982 long offset = fragP->fr_offset;
1983 /* Recompute was_address by undoing "+= stretch" done by relax_segment. */
1984 unsigned long was_address = fragP->fr_address - stretch;
1985 unsigned long address = fragP->fr_address;
1986 const relax_typeS *table = TC_GENERIC_RELAX_TABLE;
1988 this_state = fragP->fr_subtype;
1989 start_type = this_type = table + this_state;
1990 target = offset;
1992 if (symbolP)
1994 #ifndef DIFF_EXPR_OK
1995 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
1996 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
1997 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
1998 || (S_GET_SEGMENT (symbolP) == SEG_BSS)
1999 || (S_GET_SEGMENT (symbolP) == SEG_TEXT));
2000 #endif
2001 know (symbolP->sy_frag);
2002 #endif
2003 know (!(S_GET_SEGMENT (symbolP) == absolute_section)
2004 || symbolP->sy_frag == &zero_address_frag);
2005 target +=
2006 S_GET_VALUE (symbolP)
2007 + symbolP->sy_frag->fr_address;
2009 /* If frag has yet to be reached on this pass,
2010 assume it will move by STRETCH just as we did.
2011 If this is not so, it will be because some frag
2012 between grows, and that will force another pass.
2014 Beware zero-length frags.
2016 There should be a faster way to do this. */
2018 if (symbolP->sy_frag->fr_address >= was_address
2019 && is_dnrange (fragP, symbolP->sy_frag))
2021 target += stretch;
2025 aim = target - address - fragP->fr_fix;
2026 #ifdef TC_PCREL_ADJUST
2027 /* Currently only the ns32k family needs this */
2028 aim += TC_PCREL_ADJUST(fragP);
2029 /*#else*/
2030 /* This machine doesn't want to use pcrel_adjust.
2031 In that case, pcrel_adjust should be zero. */
2032 /* assert (fragP->fr_targ.ns32k.pcrel_adjust == 0);*/
2033 #endif
2034 #ifdef md_prepare_relax_scan /* formerly called M68K_AIM_KLUDGE */
2035 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2036 #endif
2038 if (aim < 0)
2040 /* Look backwards. */
2041 for (next_state = this_type->rlx_more; next_state;)
2042 if (aim >= this_type->rlx_backward)
2043 next_state = 0;
2044 else
2046 /* Grow to next state. */
2047 this_state = next_state;
2048 this_type = table + this_state;
2049 next_state = this_type->rlx_more;
2052 else
2054 /* Look forwards. */
2055 for (next_state = this_type->rlx_more; next_state;)
2056 if (aim <= this_type->rlx_forward)
2057 next_state = 0;
2058 else
2060 /* Grow to next state. */
2061 this_state = next_state;
2062 this_type = table + this_state;
2063 next_state = this_type->rlx_more;
2067 growth = this_type->rlx_length - start_type->rlx_length;
2068 if (growth != 0)
2069 fragP->fr_subtype = this_state;
2070 return growth;
2073 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2075 /* Relax_align. Advance location counter to next address that has 'alignment'
2076 lowest order bits all 0s, return size of adjustment made. */
2077 static relax_addressT
2078 relax_align (address, alignment)
2079 register relax_addressT address; /* Address now. */
2080 register int alignment; /* Alignment (binary). */
2082 relax_addressT mask;
2083 relax_addressT new_address;
2085 mask = ~((~0) << alignment);
2086 new_address = (address + mask) & (~mask);
2087 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2088 if (linkrelax)
2089 /* We must provide lots of padding, so the linker can discard it
2090 when needed. The linker will not add extra space, ever. */
2091 new_address += (1 << alignment);
2092 #endif
2093 return (new_address - address);
2096 void
2097 relax_segment (segment_frag_root, segment)
2098 struct frag *segment_frag_root;
2099 segT segment;
2101 register struct frag *fragP;
2102 register relax_addressT address;
2103 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2104 know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
2105 #endif
2106 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2107 subseg_change (segment, 0);
2109 /* For each frag in segment: count and store (a 1st guess of)
2110 fr_address. */
2111 address = 0;
2112 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2114 fragP->fr_address = address;
2115 address += fragP->fr_fix;
2117 switch (fragP->fr_type)
2119 case rs_fill:
2120 address += fragP->fr_offset * fragP->fr_var;
2121 break;
2123 case rs_align:
2124 case rs_align_code:
2126 addressT offset = relax_align (address, (int) fragP->fr_offset);
2128 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2129 offset = 0;
2131 if (offset % fragP->fr_var != 0)
2133 as_bad (_("alignment padding (%lu bytes) not a multiple of %ld"),
2134 (unsigned long) offset, (long) fragP->fr_var);
2135 offset -= (offset % fragP->fr_var);
2138 address += offset;
2140 break;
2142 case rs_org:
2143 case rs_space:
2144 /* Assume .org is nugatory. It will grow with 1st relax. */
2145 break;
2147 case rs_machine_dependent:
2148 address += md_estimate_size_before_relax (fragP, segment);
2149 break;
2151 #ifndef WORKING_DOT_WORD
2152 /* Broken words don't concern us yet */
2153 case rs_broken_word:
2154 break;
2155 #endif
2157 case rs_leb128:
2158 /* Initial guess is always 1; doing otherwise can result in
2159 stable solutions that are larger than the minimum. */
2160 address += fragP->fr_offset = 1;
2161 break;
2163 case rs_cfa:
2164 address += eh_frame_estimate_size_before_relax (fragP);
2165 break;
2167 default:
2168 BAD_CASE (fragP->fr_type);
2169 break;
2170 } /* switch(fr_type) */
2171 } /* for each frag in the segment */
2173 /* Do relax(). */
2175 long stretch; /* May be any size, 0 or negative. */
2176 /* Cumulative number of addresses we have */
2177 /* relaxed this pass. */
2178 /* We may have relaxed more than one address. */
2179 long stretched; /* Have we stretched on this pass? */
2180 /* This is 'cuz stretch may be zero, when, in fact some piece of code
2181 grew, and another shrank. If a branch instruction doesn't fit anymore,
2182 we could be scrod. */
2186 stretch = stretched = 0;
2187 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2189 long growth = 0;
2190 addressT was_address;
2191 offsetT offset;
2192 symbolS *symbolP;
2194 was_address = fragP->fr_address;
2195 address = fragP->fr_address += stretch;
2196 symbolP = fragP->fr_symbol;
2197 offset = fragP->fr_offset;
2199 switch (fragP->fr_type)
2201 case rs_fill: /* .fill never relaxes. */
2202 growth = 0;
2203 break;
2205 #ifndef WORKING_DOT_WORD
2206 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2207 for it I do not want to write it. I do not want to have
2208 anything to do with it. This is not the proper way to
2209 implement this misfeature. */
2210 case rs_broken_word:
2212 struct broken_word *lie;
2213 struct broken_word *untruth;
2215 /* Yes this is ugly (storing the broken_word pointer
2216 in the symbol slot). Still, this whole chunk of
2217 code is ugly, and I don't feel like doing anything
2218 about it. Think of it as stubbornness in action. */
2219 growth = 0;
2220 for (lie = (struct broken_word *) (fragP->fr_symbol);
2221 lie && lie->dispfrag == fragP;
2222 lie = lie->next_broken_word)
2225 if (lie->added)
2226 continue;
2228 offset = (lie->add->sy_frag->fr_address
2229 + S_GET_VALUE (lie->add)
2230 + lie->addnum
2231 - (lie->sub->sy_frag->fr_address
2232 + S_GET_VALUE (lie->sub)));
2233 if (offset <= -32768 || offset >= 32767)
2235 if (flag_warn_displacement)
2237 char buf[50];
2238 sprint_value (buf, (addressT) lie->addnum);
2239 as_warn (_(".word %s-%s+%s didn't fit"),
2240 S_GET_NAME (lie->add),
2241 S_GET_NAME (lie->sub),
2242 buf);
2244 lie->added = 1;
2245 if (fragP->fr_subtype == 0)
2247 fragP->fr_subtype++;
2248 growth += md_short_jump_size;
2250 for (untruth = lie->next_broken_word;
2251 untruth && untruth->dispfrag == lie->dispfrag;
2252 untruth = untruth->next_broken_word)
2253 if ((untruth->add->sy_frag == lie->add->sy_frag)
2254 && S_GET_VALUE (untruth->add) == S_GET_VALUE (lie->add))
2256 untruth->added = 2;
2257 untruth->use_jump = lie;
2259 growth += md_long_jump_size;
2263 break;
2264 } /* case rs_broken_word */
2265 #endif
2266 case rs_align:
2267 case rs_align_code:
2269 addressT oldoff, newoff;
2271 oldoff = relax_align (was_address + fragP->fr_fix,
2272 (int) offset);
2273 newoff = relax_align (address + fragP->fr_fix,
2274 (int) offset);
2276 if (fragP->fr_subtype != 0)
2278 if (oldoff > fragP->fr_subtype)
2279 oldoff = 0;
2280 if (newoff > fragP->fr_subtype)
2281 newoff = 0;
2284 growth = newoff - oldoff;
2286 break;
2288 case rs_org:
2290 long target = offset;
2291 long after;
2293 if (symbolP)
2295 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2296 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2297 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2298 || (S_GET_SEGMENT (symbolP) == SEG_TEXT)
2299 || S_GET_SEGMENT (symbolP) == SEG_BSS);
2300 know (symbolP->sy_frag);
2301 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2302 || (symbolP->sy_frag == &zero_address_frag));
2303 #endif
2304 target += S_GET_VALUE (symbolP)
2305 + symbolP->sy_frag->fr_address;
2306 } /* if we have a symbol */
2308 know (fragP->fr_next);
2309 after = fragP->fr_next->fr_address;
2310 growth = target - after;
2311 if (growth < 0)
2313 /* Growth may be negative, but variable part of frag
2314 cannot have fewer than 0 chars. That is, we can't
2315 .org backwards. */
2316 as_bad (_("attempt to .org backwards ignored"));
2317 growth = 0;
2320 growth -= stretch; /* This is an absolute growth factor */
2321 break;
2324 case rs_space:
2325 if (symbolP)
2327 growth = S_GET_VALUE (symbolP);
2328 if (symbolP->sy_frag != &zero_address_frag
2329 || S_IS_COMMON (symbolP)
2330 || ! S_IS_DEFINED (symbolP))
2331 as_bad_where (fragP->fr_file, fragP->fr_line,
2332 _(".space specifies non-absolute value"));
2333 fragP->fr_symbol = 0;
2334 if (growth < 0)
2336 as_warn (_(".space or .fill with negative value, ignored"));
2337 growth = 0;
2340 else
2341 growth = 0;
2342 break;
2344 case rs_machine_dependent:
2345 #ifdef md_relax_frag
2346 growth = md_relax_frag (fragP, stretch);
2347 #else
2348 #ifdef TC_GENERIC_RELAX_TABLE
2349 /* The default way to relax a frag is to look through
2350 TC_GENERIC_RELAX_TABLE. */
2351 growth = relax_frag (fragP, stretch);
2352 #endif /* TC_GENERIC_RELAX_TABLE */
2353 #endif
2354 break;
2356 case rs_leb128:
2358 valueT value;
2359 int size;
2361 value = resolve_symbol_value (fragP->fr_symbol, 0);
2362 size = sizeof_leb128 (value, fragP->fr_subtype);
2363 growth = size - fragP->fr_offset;
2364 fragP->fr_offset = size;
2366 break;
2368 case rs_cfa:
2369 growth = eh_frame_relax_frag (fragP);
2370 break;
2372 default:
2373 BAD_CASE (fragP->fr_type);
2374 break;
2376 if (growth)
2378 stretch += growth;
2379 stretched++;
2381 } /* For each frag in the segment. */
2383 while (stretched); /* Until nothing further to relax. */
2384 } /* do_relax */
2387 * We now have valid fr_address'es for each frag.
2391 * All fr_address's are correct, relative to their own segment.
2392 * We have made all the fixS we will ever make.
2394 } /* relax_segment() */
2396 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
2398 #ifndef TC_RELOC_RTSYM_LOC_FIXUP
2399 #define TC_RELOC_RTSYM_LOC_FIXUP(X) (1)
2400 #endif
2402 /* fixup_segment()
2404 Go through all the fixS's in a segment and see which ones can be
2405 handled now. (These consist of fixS where we have since discovered
2406 the value of a symbol, or the address of the frag involved.)
2407 For each one, call md_apply_fix to put the fix into the frag data.
2409 Result is a count of how many relocation structs will be needed to
2410 handle the remaining fixS's that we couldn't completely handle here.
2411 These will be output later by emit_relocations(). */
2413 static long
2414 fixup_segment (fixP, this_segment_type)
2415 register fixS *fixP;
2416 segT this_segment_type; /* N_TYPE bits for segment. */
2418 long seg_reloc_count = 0;
2419 symbolS *add_symbolP;
2420 symbolS *sub_symbolP;
2421 valueT add_number;
2422 int size;
2423 char *place;
2424 long where;
2425 int pcrel, plt;
2426 fragS *fragP;
2427 segT add_symbol_segment = absolute_section;
2429 /* If the linker is doing the relaxing, we must not do any fixups.
2431 Well, strictly speaking that's not true -- we could do any that are
2432 PC-relative and don't cross regions that could change size. And for the
2433 i960 (the only machine for which we've got a relaxing linker right now),
2434 we might be able to turn callx/callj into bal anyways in cases where we
2435 know the maximum displacement. */
2436 if (linkrelax)
2438 for (; fixP; fixP = fixP->fx_next)
2439 seg_reloc_count++;
2440 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2441 return seg_reloc_count;
2444 for (; fixP; fixP = fixP->fx_next)
2447 #ifdef DEBUG5
2448 fprintf (stderr, "\nprocessing fixup:\n");
2449 print_fixup (fixP);
2450 #endif
2453 fragP = fixP->fx_frag;
2454 know (fragP);
2455 where = fixP->fx_where;
2456 place = fragP->fr_literal + where;
2457 size = fixP->fx_size;
2458 add_symbolP = fixP->fx_addsy;
2459 #ifdef TC_VALIDATE_FIX
2460 TC_VALIDATE_FIX (fixP, this_segment_type, skip);
2461 #endif
2462 sub_symbolP = fixP->fx_subsy;
2463 add_number = fixP->fx_offset;
2464 pcrel = fixP->fx_pcrel;
2465 plt = fixP->fx_plt;
2467 if (add_symbolP != NULL
2468 && add_symbolP->sy_mri_common)
2470 know (add_symbolP->sy_value.X_op == O_symbol);
2471 add_number += S_GET_VALUE (add_symbolP);
2472 fixP->fx_offset = add_number;
2473 add_symbolP = fixP->fx_addsy = add_symbolP->sy_value.X_add_symbol;
2476 if (add_symbolP)
2477 add_symbol_segment = S_GET_SEGMENT (add_symbolP);
2479 if (sub_symbolP)
2481 resolve_symbol_value (sub_symbolP, 1);
2482 if (add_symbolP == NULL || add_symbol_segment == absolute_section)
2484 if (add_symbolP != NULL)
2486 add_number += S_GET_VALUE (add_symbolP);
2487 add_symbolP = NULL;
2488 fixP->fx_addsy = NULL;
2491 /* It's just -sym */
2492 if (S_GET_SEGMENT (sub_symbolP) == absolute_section)
2494 add_number -= S_GET_VALUE (sub_symbolP);
2495 fixP->fx_subsy = NULL;
2497 else if (pcrel
2498 && S_GET_SEGMENT (sub_symbolP) == this_segment_type)
2500 /* Should try converting to a constant. */
2501 goto bad_sub_reloc;
2503 else
2504 bad_sub_reloc:
2505 as_bad_where (fixP->fx_file, fixP->fx_line,
2506 _("Negative of non-absolute symbol %s"),
2507 S_GET_NAME (sub_symbolP));
2509 else if (S_GET_SEGMENT (sub_symbolP) == add_symbol_segment
2510 && SEG_NORMAL (add_symbol_segment))
2512 /* Difference of 2 symbols from same segment.
2513 Can't make difference of 2 undefineds: 'value' means
2514 something different for N_UNDF. */
2515 #ifdef TC_I960
2516 /* Makes no sense to use the difference of 2 arbitrary symbols
2517 as the target of a call instruction. */
2518 if (fixP->fx_tcbit)
2519 as_bad_where (fixP->fx_file, fixP->fx_line,
2520 _("callj to difference of 2 symbols"));
2521 #endif /* TC_I960 */
2522 add_number += S_GET_VALUE (add_symbolP) -
2523 S_GET_VALUE (sub_symbolP);
2525 add_symbolP = NULL;
2526 pcrel = 0; /* No further pcrel processing. */
2528 /* Let the target machine make the final determination
2529 as to whether or not a relocation will be needed to
2530 handle this fixup. */
2531 if (!TC_FORCE_RELOCATION_SECTION (fixP, this_segment_type))
2533 fixP->fx_pcrel = 0;
2534 fixP->fx_addsy = NULL;
2535 fixP->fx_subsy = NULL;
2538 else
2540 /* Different segments in subtraction. */
2541 know (!(S_IS_EXTERNAL (sub_symbolP)
2542 && (S_GET_SEGMENT (sub_symbolP) == absolute_section)));
2544 if ((S_GET_SEGMENT (sub_symbolP) == absolute_section))
2545 add_number -= S_GET_VALUE (sub_symbolP);
2547 #ifdef DIFF_EXPR_OK
2548 else if (S_GET_SEGMENT (sub_symbolP) == this_segment_type
2549 #if 0 /* Do this even if it's already described as pc-relative. For example,
2550 on the m68k, an operand of "pc@(foo-.-2)" should address "foo" in a
2551 pc-relative mode. */
2552 && pcrel
2553 #endif
2556 /* Make it pc-relative. */
2557 add_number += (MD_PCREL_FROM_SECTION (fixP, this_segment_type)
2558 - S_GET_VALUE (sub_symbolP));
2559 pcrel = 1;
2560 fixP->fx_pcrel = 1;
2561 sub_symbolP = 0;
2562 fixP->fx_subsy = 0;
2564 #endif
2565 #ifdef UNDEFINED_DIFFERENCE_OK
2566 /* The PA needs this for PIC code generation. We basically
2567 don't want to do anything if we have the difference of two
2568 symbols at this point. */
2569 else if (1)
2571 /* Leave it alone. */
2573 #endif
2574 #ifdef BFD_ASSEMBLER
2575 else if (fixP->fx_r_type == BFD_RELOC_GPREL32
2576 || fixP->fx_r_type == BFD_RELOC_GPREL16)
2578 /* Leave it alone. */
2580 #endif
2581 else
2583 char buf[50];
2584 sprint_value (buf, fragP->fr_address + where);
2585 as_bad_where (fixP->fx_file, fixP->fx_line,
2586 _("Subtraction of two symbols in different sections \"%s\" {%s section} - \"%s\" {%s section} at file address %s."),
2587 S_GET_NAME (add_symbolP),
2588 segment_name (S_GET_SEGMENT (add_symbolP)),
2589 S_GET_NAME (sub_symbolP),
2590 segment_name (S_GET_SEGMENT (sub_symbolP)),
2591 buf);
2596 if (add_symbolP)
2598 if (add_symbol_segment == this_segment_type && pcrel && !plt
2599 && TC_RELOC_RTSYM_LOC_FIXUP (fixP))
2602 * This fixup was made when the symbol's segment was
2603 * SEG_UNKNOWN, but it is now in the local segment.
2604 * So we know how to do the address without relocation.
2606 #ifdef TC_I960
2607 /* reloc_callj() may replace a 'call' with a 'calls' or a
2608 'bal', in which cases it modifies *fixP as appropriate.
2609 In the case of a 'calls', no further work is required,
2610 and *fixP has been set up to make the rest of the code
2611 below a no-op. */
2612 reloc_callj (fixP);
2613 #endif /* TC_I960 */
2615 add_number += S_GET_VALUE (add_symbolP);
2616 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment_type);
2617 pcrel = 0; /* Lie. Don't want further pcrel processing. */
2619 /* Let the target machine make the final determination
2620 as to whether or not a relocation will be needed to
2621 handle this fixup. */
2622 if (!TC_FORCE_RELOCATION (fixP))
2624 fixP->fx_pcrel = 0;
2625 fixP->fx_addsy = NULL;
2628 else
2630 if (add_symbol_segment == absolute_section
2631 && ! pcrel)
2633 #ifdef TC_I960
2634 /* See comment about reloc_callj() above. */
2635 reloc_callj (fixP);
2636 #endif /* TC_I960 */
2637 add_number += S_GET_VALUE (add_symbolP);
2639 /* Let the target machine make the final determination
2640 as to whether or not a relocation will be needed to
2641 handle this fixup. */
2643 if (!TC_FORCE_RELOCATION (fixP))
2645 fixP->fx_addsy = NULL;
2646 add_symbolP = NULL;
2649 else if (add_symbol_segment == undefined_section
2650 #ifdef BFD_ASSEMBLER
2651 || bfd_is_com_section (add_symbol_segment)
2652 #endif
2655 #ifdef TC_I960
2656 if ((int) fixP->fx_bit_fixP == 13)
2658 /* This is a COBR instruction. They have only a
2659 * 13-bit displacement and are only to be used
2660 * for local branches: flag as error, don't generate
2661 * relocation.
2663 as_bad_where (fixP->fx_file, fixP->fx_line,
2664 _("can't use COBR format with external label"));
2665 fixP->fx_addsy = NULL;
2666 fixP->fx_done = 1;
2667 continue;
2668 } /* COBR */
2669 #endif /* TC_I960 */
2671 #ifdef OBJ_COFF
2672 #ifdef TE_I386AIX
2673 if (S_IS_COMMON (add_symbolP))
2674 add_number += S_GET_VALUE (add_symbolP);
2675 #endif /* TE_I386AIX */
2676 #endif /* OBJ_COFF */
2677 ++seg_reloc_count;
2679 else
2681 seg_reloc_count++;
2682 #if !(defined (TC_V850) && defined (OBJ_ELF))
2683 #if !(defined (TC_M68K) && defined (OBJ_ELF))
2684 #if !(defined (TC_ARM) && defined (OBJ_ELF))
2685 #if !defined (TC_I386) || !(defined (OBJ_ELF) || defined (OBJ_COFF)) || defined (TE_PE)
2686 add_number += S_GET_VALUE (add_symbolP);
2687 #endif
2688 #endif
2689 #endif
2690 #endif
2695 if (pcrel)
2697 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment_type);
2698 if (add_symbolP == 0)
2700 #ifndef BFD_ASSEMBLER
2701 fixP->fx_addsy = &abs_symbol;
2702 #else
2703 fixP->fx_addsy = section_symbol (absolute_section);
2704 #endif
2705 fixP->fx_addsy->sy_used_in_reloc = 1;
2706 ++seg_reloc_count;
2710 if (!fixP->fx_done)
2712 #ifdef MD_APPLY_FIX3
2713 md_apply_fix3 (fixP, &add_number, this_segment_type);
2714 #else
2715 #ifdef BFD_ASSEMBLER
2716 md_apply_fix (fixP, &add_number);
2717 #else
2718 md_apply_fix (fixP, add_number);
2719 #endif
2720 #endif
2722 #ifndef TC_HANDLES_FX_DONE
2723 /* If the tc-* files haven't been converted, assume it's handling
2724 it the old way, where a null fx_addsy means that the fix has
2725 been applied completely, and no further work is needed. */
2726 if (fixP->fx_addsy == 0 && fixP->fx_pcrel == 0)
2727 fixP->fx_done = 1;
2728 #endif
2731 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && size > 0)
2733 if ((size_t) size < sizeof (valueT))
2735 valueT mask, hibit;
2737 /* set all bits to one */
2738 mask = 0;
2739 mask--;
2740 /* Technically, combining these produces an undefined result
2741 if size is sizeof (valueT), though I think these two
2742 half-way operations should both be defined. And the
2743 compiler should be able to combine them if it's valid on
2744 the host architecture. */
2745 mask <<= size * 4;
2746 mask <<= size * 4;
2747 hibit = (valueT) 1 << (size * 8 - 1);
2748 if (((add_number & mask) != 0
2749 || (fixP->fx_signed
2750 && (add_number & hibit) != 0))
2751 && ((add_number & mask) != mask
2752 || (add_number & hibit) == 0))
2754 char buf[50], buf2[50];
2755 sprint_value (buf, fragP->fr_address + where);
2756 if (add_number > 1000)
2757 sprint_value (buf2, add_number);
2758 else
2759 sprintf (buf2, "%ld", (long) add_number);
2760 as_bad_where (fixP->fx_file, fixP->fx_line,
2761 _("Value of %s too large for field of %d bytes at %s"),
2762 buf2, size, buf);
2763 } /* generic error checking */
2765 #ifdef WARN_SIGNED_OVERFLOW_WORD
2766 /* Warn if a .word value is too large when treated as a signed
2767 number. We already know it is not too negative. This is to
2768 catch over-large switches generated by gcc on the 68k. */
2769 if (!flag_signed_overflow_ok
2770 && size == 2
2771 && add_number > 0x7fff)
2772 as_bad_where (fixP->fx_file, fixP->fx_line,
2773 _("Signed .word overflow; switch may be too large; %ld at 0x%lx"),
2774 (long) add_number,
2775 (unsigned long) (fragP->fr_address + where));
2776 #endif
2777 } /* not a bit fix */
2779 #ifdef TC_VALIDATE_FIX
2780 skip: ;
2781 #endif
2782 #ifdef DEBUG5
2783 fprintf (stderr, "result:\n");
2784 print_fixup (fixP);
2785 #endif
2786 } /* For each fixS in this segment. */
2788 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2789 return seg_reloc_count;
2792 #endif /* defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS)) */
2794 void
2795 number_to_chars_bigendian (buf, val, n)
2796 char *buf;
2797 valueT val;
2798 int n;
2800 if ((size_t) n > sizeof (val) || n <= 0)
2801 abort ();
2802 while (n--)
2804 buf[n] = val & 0xff;
2805 val >>= 8;
2809 void
2810 number_to_chars_littleendian (buf, val, n)
2811 char *buf;
2812 valueT val;
2813 int n;
2815 if ((size_t) n > sizeof (val) || n <= 0)
2816 abort ();
2817 while (n--)
2819 *buf++ = val & 0xff;
2820 val >>= 8;
2824 void
2825 write_print_statistics (file)
2826 FILE *file;
2828 fprintf (file, "fixups: %d\n", n_fixups);
2831 /* for debugging */
2832 extern int indent_level;
2834 void
2835 print_fixup (fixp)
2836 fixS *fixp;
2838 indent_level = 1;
2839 fprintf (stderr, "fix %lx %s:%d", (long) fixp, fixp->fx_file, fixp->fx_line);
2840 if (fixp->fx_pcrel)
2841 fprintf (stderr, " pcrel");
2842 if (fixp->fx_pcrel_adjust)
2843 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2844 if (fixp->fx_im_disp)
2846 #ifdef TC_NS32K
2847 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2848 #else
2849 fprintf (stderr, " im_disp");
2850 #endif
2852 if (fixp->fx_tcbit)
2853 fprintf (stderr, " tcbit");
2854 if (fixp->fx_done)
2855 fprintf (stderr, " done");
2856 fprintf (stderr, "\n size=%d frag=%lx where=%ld offset=%lx addnumber=%lx",
2857 fixp->fx_size, (long) fixp->fx_frag, (long) fixp->fx_where,
2858 (long) fixp->fx_offset, (long) fixp->fx_addnumber);
2859 #ifdef BFD_ASSEMBLER
2860 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2861 fixp->fx_r_type);
2862 #else
2863 #ifdef NEED_FX_R_TYPE
2864 fprintf (stderr, " r_type=%d", fixp->fx_r_type);
2865 #endif
2866 #endif
2867 if (fixp->fx_addsy)
2869 fprintf (stderr, "\n +<");
2870 print_symbol_value_1 (stderr, fixp->fx_addsy);
2871 fprintf (stderr, ">");
2873 if (fixp->fx_subsy)
2875 fprintf (stderr, "\n -<");
2876 print_symbol_value_1 (stderr, fixp->fx_subsy);
2877 fprintf (stderr, ">");
2879 fprintf (stderr, "\n");
2880 #ifdef TC_FIX_DATA_PRINT
2881 TC_FIX_DATA_PRINT (stderr, fixp);
2882 #endif
2885 /* end of write.c */