2004-08-31 Robert Bowdidge <bowdidge@apple.com>
[binutils.git] / gas / write.c
bloba713a9d3981162556b1487e2d24201a6c8c68ef3
1 /* write.c - emit .o file
2 Copyright 1986, 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004
4 Free Software Foundation, Inc.
6 This file is part of GAS, the GNU Assembler.
8 GAS is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
13 GAS is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GAS; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 02111-1307, USA. */
23 /* This thing should be set up to do byteordering correctly. But... */
25 #include "as.h"
26 #include "subsegs.h"
27 #include "obstack.h"
28 #include "output-file.h"
29 #include "dwarf2dbg.h"
31 #ifndef TC_ADJUST_RELOC_COUNT
32 #define TC_ADJUST_RELOC_COUNT(FIX, COUNT)
33 #endif
35 #ifndef TC_FORCE_RELOCATION
36 #define TC_FORCE_RELOCATION(FIX) \
37 (generic_force_reloc (FIX))
38 #endif
40 #ifndef TC_FORCE_RELOCATION_ABS
41 #define TC_FORCE_RELOCATION_ABS(FIX) \
42 (TC_FORCE_RELOCATION (FIX))
43 #endif
45 #ifndef TC_FORCE_RELOCATION_LOCAL
46 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
47 (!(FIX)->fx_pcrel \
48 || (FIX)->fx_plt \
49 || TC_FORCE_RELOCATION (FIX))
50 #endif
52 #ifndef TC_FORCE_RELOCATION_SUB_SAME
53 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
54 (! SEG_NORMAL (SEG))
55 #endif
57 #ifndef TC_FORCE_RELOCATION_SUB_ABS
58 #define TC_FORCE_RELOCATION_SUB_ABS(FIX) 0
59 #endif
61 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
62 #ifdef DIFF_EXPR_OK
63 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 0
64 #else
65 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX) 1
66 #endif
67 #endif
69 #ifndef TC_VALIDATE_FIX_SUB
70 #ifdef UNDEFINED_DIFFERENCE_OK
71 /* The PA needs this for PIC code generation. */
72 #define TC_VALIDATE_FIX_SUB(FIX) 1
73 #else
74 #ifdef BFD_ASSEMBLER
75 #define TC_VALIDATE_FIX_SUB(FIX) \
76 ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
77 || (FIX)->fx_r_type == BFD_RELOC_GPREL16)
78 #else
79 #define TC_VALIDATE_FIX_SUB(FIX) 0
80 #endif
81 #endif
82 #endif
84 #ifndef TC_LINKRELAX_FIXUP
85 #define TC_LINKRELAX_FIXUP(SEG) 1
86 #endif
88 #ifndef MD_APPLY_SYM_VALUE
89 #define MD_APPLY_SYM_VALUE(FIX) 1
90 #endif
92 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
93 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
94 #endif
96 #ifndef MD_PCREL_FROM_SECTION
97 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
98 #endif
100 #ifndef WORKING_DOT_WORD
101 extern const int md_short_jump_size;
102 extern const int md_long_jump_size;
103 #endif
105 /* Used to control final evaluation of expressions. */
106 int finalize_syms = 0;
108 int symbol_table_frozen;
110 symbolS *abs_section_sym;
112 /* Remember the value of dot when parsing expressions. */
113 addressT dot_value;
115 void print_fixup (fixS *);
117 #ifdef BFD_ASSEMBLER
118 static void renumber_sections (bfd *, asection *, PTR);
120 /* We generally attach relocs to frag chains. However, after we have
121 chained these all together into a segment, any relocs we add after
122 that must be attached to a segment. This will include relocs added
123 in md_estimate_size_for_relax, for example. */
124 static int frags_chained = 0;
125 #endif
127 #ifndef BFD_ASSEMBLER
129 #ifndef MANY_SEGMENTS
130 struct frag *text_frag_root;
131 struct frag *data_frag_root;
132 struct frag *bss_frag_root;
134 struct frag *text_last_frag; /* Last frag in segment. */
135 struct frag *data_last_frag; /* Last frag in segment. */
136 static struct frag *bss_last_frag; /* Last frag in segment. */
137 #endif
139 #ifndef BFD
140 static object_headers headers;
141 #endif
143 long string_byte_count;
144 char *next_object_file_charP; /* Tracks object file bytes. */
146 #ifndef OBJ_VMS
147 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
148 #endif
150 #endif /* BFD_ASSEMBLER */
152 static int n_fixups;
154 #ifdef BFD_ASSEMBLER
155 #define RELOC_ENUM enum bfd_reloc_code_real
156 #else
157 #define RELOC_ENUM int
158 #endif
160 static fixS *fix_new_internal (fragS *, int where, int size,
161 symbolS *add, symbolS *sub,
162 offsetT offset, int pcrel,
163 RELOC_ENUM r_type);
164 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
165 static long fixup_segment (fixS *, segT);
166 #endif
167 static relax_addressT relax_align (relax_addressT addr, int align);
168 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
169 static fragS *chain_frchains_together_1 (segT, struct frchain *);
170 #endif
171 #ifdef BFD_ASSEMBLER
172 static void chain_frchains_together (bfd *, segT, PTR);
173 static void cvt_frag_to_fill (segT, fragS *);
174 static void adjust_reloc_syms (bfd *, asection *, PTR);
175 static void fix_segment (bfd *, asection *, PTR);
176 static void write_relocs (bfd *, asection *, PTR);
177 static void write_contents (bfd *, asection *, PTR);
178 static void set_symtab (void);
179 #endif
180 #if defined (BFD_ASSEMBLER) || (! defined (BFD) && ! defined (OBJ_AOUT))
181 static void merge_data_into_text (void);
182 #endif
183 #if ! defined (BFD_ASSEMBLER) && ! defined (BFD)
184 static void cvt_frag_to_fill (object_headers *, segT, fragS *);
185 static void remove_subsegs (frchainS *, int, fragS **, fragS **);
186 static void relax_and_size_all_segments (void);
187 #endif
189 /* Create a fixS in obstack 'notes'. */
191 static fixS *
192 fix_new_internal (fragS *frag, /* Which frag? */
193 int where, /* Where in that frag? */
194 int size, /* 1, 2, or 4 usually. */
195 symbolS *add_symbol, /* X_add_symbol. */
196 symbolS *sub_symbol, /* X_op_symbol. */
197 offsetT offset, /* X_add_number. */
198 int pcrel, /* TRUE if PC-relative relocation. */
199 RELOC_ENUM r_type ATTRIBUTE_UNUSED /* Relocation type. */)
201 fixS *fixP;
203 n_fixups++;
205 fixP = (fixS *) obstack_alloc (&notes, sizeof (fixS));
207 fixP->fx_frag = frag;
208 fixP->fx_where = where;
209 fixP->fx_size = size;
210 /* We've made fx_size a narrow field; check that it's wide enough. */
211 if (fixP->fx_size != size)
213 as_bad (_("field fx_size too small to hold %d"), size);
214 abort ();
216 fixP->fx_addsy = add_symbol;
217 fixP->fx_subsy = sub_symbol;
218 fixP->fx_offset = offset;
219 fixP->fx_dot_value = dot_value;
220 fixP->fx_pcrel = pcrel;
221 fixP->fx_plt = 0;
222 #if defined(NEED_FX_R_TYPE) || defined (BFD_ASSEMBLER)
223 fixP->fx_r_type = r_type;
224 #endif
225 fixP->fx_im_disp = 0;
226 fixP->fx_pcrel_adjust = 0;
227 fixP->fx_bit_fixP = 0;
228 fixP->fx_addnumber = 0;
229 fixP->fx_tcbit = 0;
230 fixP->fx_done = 0;
231 fixP->fx_no_overflow = 0;
232 fixP->fx_signed = 0;
234 #ifdef USING_CGEN
235 fixP->fx_cgen.insn = NULL;
236 fixP->fx_cgen.opinfo = 0;
237 #endif
239 #ifdef TC_FIX_TYPE
240 TC_INIT_FIX_DATA (fixP);
241 #endif
243 as_where (&fixP->fx_file, &fixP->fx_line);
245 /* Usually, we want relocs sorted numerically, but while
246 comparing to older versions of gas that have relocs
247 reverse sorted, it is convenient to have this compile
248 time option. xoxorich. */
251 #ifdef BFD_ASSEMBLER
252 fixS **seg_fix_rootP = (frags_chained
253 ? &seg_info (now_seg)->fix_root
254 : &frchain_now->fix_root);
255 fixS **seg_fix_tailP = (frags_chained
256 ? &seg_info (now_seg)->fix_tail
257 : &frchain_now->fix_tail);
258 #endif
260 #ifdef REVERSE_SORT_RELOCS
262 fixP->fx_next = *seg_fix_rootP;
263 *seg_fix_rootP = fixP;
265 #else /* REVERSE_SORT_RELOCS */
267 fixP->fx_next = NULL;
269 if (*seg_fix_tailP)
270 (*seg_fix_tailP)->fx_next = fixP;
271 else
272 *seg_fix_rootP = fixP;
273 *seg_fix_tailP = fixP;
275 #endif /* REVERSE_SORT_RELOCS */
278 return fixP;
281 /* Create a fixup relative to a symbol (plus a constant). */
283 fixS *
284 fix_new (fragS *frag, /* Which frag? */
285 int where, /* Where in that frag? */
286 int size, /* 1, 2, or 4 usually. */
287 symbolS *add_symbol, /* X_add_symbol. */
288 offsetT offset, /* X_add_number. */
289 int pcrel, /* TRUE if PC-relative relocation. */
290 RELOC_ENUM r_type /* Relocation type. */)
292 return fix_new_internal (frag, where, size, add_symbol,
293 (symbolS *) NULL, offset, pcrel, r_type);
296 /* Create a fixup for an expression. Currently we only support fixups
297 for difference expressions. That is itself more than most object
298 file formats support anyhow. */
300 fixS *
301 fix_new_exp (fragS *frag, /* Which frag? */
302 int where, /* Where in that frag? */
303 int size, /* 1, 2, or 4 usually. */
304 expressionS *exp, /* Expression. */
305 int pcrel, /* TRUE if PC-relative relocation. */
306 RELOC_ENUM r_type /* Relocation type. */)
308 symbolS *add = NULL;
309 symbolS *sub = NULL;
310 offsetT off = 0;
312 switch (exp->X_op)
314 case O_absent:
315 break;
317 case O_register:
318 as_bad (_("register value used as expression"));
319 break;
321 case O_add:
322 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
323 the difference expression cannot immediately be reduced. */
325 symbolS *stmp = make_expr_symbol (exp);
327 exp->X_op = O_symbol;
328 exp->X_op_symbol = 0;
329 exp->X_add_symbol = stmp;
330 exp->X_add_number = 0;
332 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
335 case O_symbol_rva:
336 add = exp->X_add_symbol;
337 off = exp->X_add_number;
339 #if defined(BFD_ASSEMBLER)
340 r_type = BFD_RELOC_RVA;
341 #else
342 #if defined(TC_RVA_RELOC)
343 r_type = TC_RVA_RELOC;
344 #else
345 as_fatal (_("rva not supported"));
346 #endif
347 #endif
348 break;
350 case O_uminus:
351 sub = exp->X_add_symbol;
352 off = exp->X_add_number;
353 break;
355 case O_subtract:
356 sub = exp->X_op_symbol;
357 /* Fall through. */
358 case O_symbol:
359 add = exp->X_add_symbol;
360 /* Fall through. */
361 case O_constant:
362 off = exp->X_add_number;
363 break;
365 default:
366 add = make_expr_symbol (exp);
367 break;
370 return fix_new_internal (frag, where, size, add, sub, off, pcrel, r_type);
373 /* Generic function to determine whether a fixup requires a relocation. */
375 generic_force_reloc (fixS *fix)
377 #ifdef BFD_ASSEMBLER
378 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
379 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
380 return 1;
381 #endif
382 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
385 /* Append a string onto another string, bumping the pointer along. */
386 void
387 append (char **charPP, char *fromP, unsigned long length)
389 /* Don't trust memcpy() of 0 chars. */
390 if (length == 0)
391 return;
393 memcpy (*charPP, fromP, length);
394 *charPP += length;
397 #ifndef BFD_ASSEMBLER
398 int section_alignment[SEG_MAXIMUM_ORDINAL];
399 #endif
401 /* This routine records the largest alignment seen for each segment.
402 If the beginning of the segment is aligned on the worst-case
403 boundary, all of the other alignments within it will work. At
404 least one object format really uses this info. */
406 void
407 record_alignment (/* Segment to which alignment pertains. */
408 segT seg,
409 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
410 boundary, 2 => 4-byte boundary, etc.) */
411 int align)
413 if (seg == absolute_section)
414 return;
415 #ifdef BFD_ASSEMBLER
416 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
417 bfd_set_section_alignment (stdoutput, seg, align);
418 #else
419 if (align > section_alignment[(int) seg])
420 section_alignment[(int) seg] = align;
421 #endif
425 get_recorded_alignment (segT seg)
427 if (seg == absolute_section)
428 return 0;
429 #ifdef BFD_ASSEMBLER
430 return bfd_get_section_alignment (stdoutput, seg);
431 #else
432 return section_alignment[(int) seg];
433 #endif
436 #ifdef BFD_ASSEMBLER
438 /* Reset the section indices after removing the gas created sections. */
440 static void
441 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, PTR countparg)
443 int *countp = (int *) countparg;
445 sec->index = *countp;
446 ++*countp;
449 #endif /* defined (BFD_ASSEMBLER) */
451 #if defined (BFD_ASSEMBLER) || ! defined (BFD)
453 static fragS *
454 chain_frchains_together_1 (segT section, struct frchain *frchp)
456 fragS dummy, *prev_frag = &dummy;
457 #ifdef BFD_ASSEMBLER
458 fixS fix_dummy, *prev_fix = &fix_dummy;
459 #endif
461 for (; frchp && frchp->frch_seg == section; frchp = frchp->frch_next)
463 prev_frag->fr_next = frchp->frch_root;
464 prev_frag = frchp->frch_last;
465 assert (prev_frag->fr_type != 0);
466 #ifdef BFD_ASSEMBLER
467 if (frchp->fix_root != (fixS *) NULL)
469 if (seg_info (section)->fix_root == (fixS *) NULL)
470 seg_info (section)->fix_root = frchp->fix_root;
471 prev_fix->fx_next = frchp->fix_root;
472 seg_info (section)->fix_tail = frchp->fix_tail;
473 prev_fix = frchp->fix_tail;
475 #endif
477 assert (prev_frag->fr_type != 0);
478 prev_frag->fr_next = 0;
479 return prev_frag;
482 #endif
484 #ifdef BFD_ASSEMBLER
486 static void
487 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
488 segT section,
489 PTR xxx ATTRIBUTE_UNUSED)
491 segment_info_type *info;
493 /* BFD may have introduced its own sections without using
494 subseg_new, so it is possible that seg_info is NULL. */
495 info = seg_info (section);
496 if (info != (segment_info_type *) NULL)
497 info->frchainP->frch_last
498 = chain_frchains_together_1 (section, info->frchainP);
500 /* Now that we've chained the frags together, we must add new fixups
501 to the segment, not to the frag chain. */
502 frags_chained = 1;
505 #endif
507 #if !defined (BFD) && !defined (BFD_ASSEMBLER)
509 static void
510 remove_subsegs (frchainS *head, int seg, fragS **root, fragS **last)
512 *root = head->frch_root;
513 *last = chain_frchains_together_1 (seg, head);
516 #endif /* BFD */
518 #if defined (BFD_ASSEMBLER) || !defined (BFD)
520 #ifdef BFD_ASSEMBLER
521 static void
522 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
523 #else
524 static void
525 cvt_frag_to_fill (object_headers *headersP, segT sec, fragS *fragP)
526 #endif
528 switch (fragP->fr_type)
530 case rs_align:
531 case rs_align_code:
532 case rs_align_test:
533 case rs_org:
534 case rs_space:
535 #ifdef HANDLE_ALIGN
536 HANDLE_ALIGN (fragP);
537 #endif
538 know (fragP->fr_next != NULL);
539 fragP->fr_offset = (fragP->fr_next->fr_address
540 - fragP->fr_address
541 - fragP->fr_fix) / fragP->fr_var;
542 if (fragP->fr_offset < 0)
544 as_bad_where (fragP->fr_file, fragP->fr_line,
545 _("attempt to .org/.space backwards? (%ld)"),
546 (long) fragP->fr_offset);
547 fragP->fr_offset = 0;
549 fragP->fr_type = rs_fill;
550 break;
552 case rs_fill:
553 break;
555 case rs_leb128:
557 valueT value = S_GET_VALUE (fragP->fr_symbol);
558 int size;
560 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
561 fragP->fr_subtype);
563 fragP->fr_fix += size;
564 fragP->fr_type = rs_fill;
565 fragP->fr_var = 0;
566 fragP->fr_offset = 0;
567 fragP->fr_symbol = NULL;
569 break;
571 case rs_cfa:
572 eh_frame_convert_frag (fragP);
573 break;
575 case rs_dwarf2dbg:
576 dwarf2dbg_convert_frag (fragP);
577 break;
579 case rs_machine_dependent:
580 #ifdef BFD_ASSEMBLER
581 md_convert_frag (stdoutput, sec, fragP);
582 #else
583 md_convert_frag (headersP, sec, fragP);
584 #endif
586 assert (fragP->fr_next == NULL
587 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
588 == fragP->fr_fix));
590 /* After md_convert_frag, we make the frag into a ".space 0".
591 md_convert_frag() should set up any fixSs and constants
592 required. */
593 frag_wane (fragP);
594 break;
596 #ifndef WORKING_DOT_WORD
597 case rs_broken_word:
599 struct broken_word *lie;
601 if (fragP->fr_subtype)
603 fragP->fr_fix += md_short_jump_size;
604 for (lie = (struct broken_word *) (fragP->fr_symbol);
605 lie && lie->dispfrag == fragP;
606 lie = lie->next_broken_word)
607 if (lie->added == 1)
608 fragP->fr_fix += md_long_jump_size;
610 frag_wane (fragP);
612 break;
613 #endif
615 default:
616 BAD_CASE (fragP->fr_type);
617 break;
619 #ifdef md_frag_check
620 md_frag_check (fragP);
621 #endif
624 #endif /* defined (BFD_ASSEMBLER) || !defined (BFD) */
626 #ifdef BFD_ASSEMBLER
627 static void relax_seg (bfd *, asection *, PTR);
629 static void
630 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, PTR xxx)
632 segment_info_type *seginfo = seg_info (sec);
634 if (seginfo && seginfo->frchainP
635 && relax_segment (seginfo->frchainP->frch_root, sec))
637 int *result = (int *) xxx;
638 *result = 1;
642 static void size_seg (bfd *, asection *, PTR);
644 static void
645 size_seg (bfd *abfd, asection *sec, PTR xxx ATTRIBUTE_UNUSED)
647 flagword flags;
648 fragS *fragp;
649 segment_info_type *seginfo;
650 int x;
651 valueT size, newsize;
653 subseg_change (sec, 0);
655 seginfo = seg_info (sec);
656 if (seginfo && seginfo->frchainP)
658 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
659 cvt_frag_to_fill (sec, fragp);
660 for (fragp = seginfo->frchainP->frch_root;
661 fragp->fr_next;
662 fragp = fragp->fr_next)
663 /* Walk to last elt. */
665 size = fragp->fr_address + fragp->fr_fix;
667 else
668 size = 0;
670 flags = bfd_get_section_flags (abfd, sec);
672 if (size > 0 && ! seginfo->bss)
673 flags |= SEC_HAS_CONTENTS;
675 /* @@ This is just an approximation. */
676 if (seginfo && seginfo->fix_root)
677 flags |= SEC_RELOC;
678 else
679 flags &= ~SEC_RELOC;
680 x = bfd_set_section_flags (abfd, sec, flags);
681 assert (x);
683 newsize = md_section_align (sec, size);
684 x = bfd_set_section_size (abfd, sec, newsize);
685 assert (x);
687 /* If the size had to be rounded up, add some padding in the last
688 non-empty frag. */
689 assert (newsize >= size);
690 if (size != newsize)
692 fragS *last = seginfo->frchainP->frch_last;
693 fragp = seginfo->frchainP->frch_root;
694 while (fragp->fr_next != last)
695 fragp = fragp->fr_next;
696 last->fr_address = size;
697 if ((newsize - size) % fragp->fr_var == 0)
698 fragp->fr_offset += (newsize - size) / fragp->fr_var;
699 else
700 /* If we hit this abort, it's likely due to subsegs_finish not
701 providing sufficient alignment on the last frag, and the
702 machine dependent code using alignment frags with fr_var
703 greater than 1. */
704 abort ();
707 #ifdef tc_frob_section
708 tc_frob_section (sec);
709 #endif
710 #ifdef obj_frob_section
711 obj_frob_section (sec);
712 #endif
715 #ifdef DEBUG2
716 static void
717 dump_section_relocs (abfd, sec, stream_)
718 bfd *abfd ATTRIBUTE_UNUSED;
719 asection *sec;
720 char *stream_;
722 FILE *stream = (FILE *) stream_;
723 segment_info_type *seginfo = seg_info (sec);
724 fixS *fixp = seginfo->fix_root;
726 if (!fixp)
727 return;
729 fprintf (stream, "sec %s relocs:\n", sec->name);
730 while (fixp)
732 symbolS *s = fixp->fx_addsy;
734 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
735 (int) fixp->fx_r_type);
736 if (s == NULL)
737 fprintf (stream, "no sym\n");
738 else
740 print_symbol_value_1 (stream, s);
741 fprintf (stream, "\n");
743 fixp = fixp->fx_next;
746 #else
747 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
748 #endif
750 #ifndef EMIT_SECTION_SYMBOLS
751 #define EMIT_SECTION_SYMBOLS 1
752 #endif
754 /* This pass over fixups decides whether symbols can be replaced with
755 section symbols. */
757 static void
758 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
759 asection *sec,
760 PTR xxx ATTRIBUTE_UNUSED)
762 segment_info_type *seginfo = seg_info (sec);
763 fixS *fixp;
765 if (seginfo == NULL)
766 return;
768 dump_section_relocs (abfd, sec, stderr);
770 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
771 if (fixp->fx_done)
772 /* Ignore it. */
774 else if (fixp->fx_addsy)
776 symbolS *sym;
777 asection *symsec;
779 #ifdef DEBUG5
780 fprintf (stderr, "\n\nadjusting fixup:\n");
781 print_fixup (fixp);
782 #endif
784 sym = fixp->fx_addsy;
786 /* All symbols should have already been resolved at this
787 point. It is possible to see unresolved expression
788 symbols, though, since they are not in the regular symbol
789 table. */
790 resolve_symbol_value (sym);
792 if (fixp->fx_subsy != NULL)
793 resolve_symbol_value (fixp->fx_subsy);
795 /* If this symbol is equated to an undefined symbol, convert
796 the fixup to being against that symbol. */
797 if (symbol_equated_reloc_p (sym))
799 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
800 sym = symbol_get_value_expression (sym)->X_add_symbol;
801 fixp->fx_addsy = sym;
804 if (symbol_mri_common_p (sym))
806 /* These symbols are handled specially in fixup_segment. */
807 continue;
810 /* If the symbol is undefined, common, weak, or global (ELF
811 shared libs), we can't replace it with the section symbol. */
812 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
813 continue;
815 /* Is there some other (target cpu dependent) reason we can't adjust
816 this one? (E.g. relocations involving function addresses on
817 the PA. */
818 #ifdef tc_fix_adjustable
819 if (! tc_fix_adjustable (fixp))
820 continue;
821 #endif
823 /* Since we're reducing to section symbols, don't attempt to reduce
824 anything that's already using one. */
825 if (symbol_section_p (sym))
826 continue;
828 symsec = S_GET_SEGMENT (sym);
829 if (symsec == NULL)
830 abort ();
832 if (bfd_is_abs_section (symsec))
834 /* The fixup_segment routine normally will not use this
835 symbol in a relocation. */
836 continue;
839 /* Don't try to reduce relocs which refer to non-local symbols
840 in .linkonce sections. It can lead to confusion when a
841 debugging section refers to a .linkonce section. I hope
842 this will always be correct. */
843 if (symsec != sec && ! S_IS_LOCAL (sym))
845 if ((symsec->flags & SEC_LINK_ONCE) != 0
846 || (IS_ELF
847 /* The GNU toolchain uses an extension for ELF: a
848 section beginning with the magic string
849 .gnu.linkonce is a linkonce section. */
850 && strncmp (segment_name (symsec), ".gnu.linkonce",
851 sizeof ".gnu.linkonce" - 1) == 0))
852 continue;
855 /* Never adjust a reloc against local symbol in a merge section
856 with non-zero addend. */
857 if ((symsec->flags & SEC_MERGE) != 0
858 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
859 continue;
861 /* Never adjust a reloc against TLS local symbol. */
862 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
863 continue;
865 /* We refetch the segment when calling section_symbol, rather
866 than using symsec, because S_GET_VALUE may wind up changing
867 the section when it calls resolve_symbol_value. */
868 fixp->fx_offset += S_GET_VALUE (sym);
869 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
870 #ifdef DEBUG5
871 fprintf (stderr, "\nadjusted fixup:\n");
872 print_fixup (fixp);
873 #endif
876 dump_section_relocs (abfd, sec, stderr);
879 static void
880 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
881 asection *sec,
882 PTR xxx ATTRIBUTE_UNUSED)
884 segment_info_type *seginfo = seg_info (sec);
886 fixup_segment (seginfo->fix_root, sec);
889 static void
890 write_relocs (bfd *abfd, asection *sec, PTR xxx ATTRIBUTE_UNUSED)
892 segment_info_type *seginfo = seg_info (sec);
893 unsigned int i;
894 unsigned int n;
895 arelent **relocs;
896 fixS *fixp;
897 char *err;
899 /* If seginfo is NULL, we did not create this section; don't do
900 anything with it. */
901 if (seginfo == NULL)
902 return;
904 n = 0;
905 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
906 n++;
908 #ifndef RELOC_EXPANSION_POSSIBLE
909 /* Set up reloc information as well. */
910 relocs = (arelent **) xcalloc (n, sizeof (arelent *));
912 i = 0;
913 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
915 arelent *reloc;
916 bfd_reloc_status_type s;
917 symbolS *sym;
919 if (fixp->fx_done)
921 n--;
922 continue;
925 /* If this is an undefined symbol which was equated to another
926 symbol, then generate the reloc against the latter symbol
927 rather than the former. */
928 sym = fixp->fx_addsy;
929 while (symbol_equated_reloc_p (sym))
931 symbolS *n;
933 /* We must avoid looping, as that can occur with a badly
934 written program. */
935 n = symbol_get_value_expression (sym)->X_add_symbol;
936 if (n == sym)
937 break;
938 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
939 sym = n;
941 fixp->fx_addsy = sym;
943 reloc = tc_gen_reloc (sec, fixp);
944 if (!reloc)
946 n--;
947 continue;
950 #if 0
951 /* This test is triggered inappropriately for the SH. */
952 if (fixp->fx_where + fixp->fx_size
953 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
954 abort ();
955 #endif
957 s = bfd_install_relocation (stdoutput, reloc,
958 fixp->fx_frag->fr_literal,
959 fixp->fx_frag->fr_address,
960 sec, &err);
961 switch (s)
963 case bfd_reloc_ok:
964 break;
965 case bfd_reloc_overflow:
966 as_bad_where (fixp->fx_file, fixp->fx_line,
967 _("relocation overflow"));
968 break;
969 case bfd_reloc_outofrange:
970 as_bad_where (fixp->fx_file, fixp->fx_line,
971 _("relocation out of range"));
972 break;
973 default:
974 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
975 fixp->fx_file, fixp->fx_line, s);
977 relocs[i++] = reloc;
979 #else
980 n = n * MAX_RELOC_EXPANSION;
981 /* Set up reloc information as well. */
982 relocs = (arelent **) xcalloc (n, sizeof (arelent *));
984 i = 0;
985 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
987 arelent **reloc;
988 bfd_reloc_status_type s;
989 symbolS *sym;
990 int j;
992 if (fixp->fx_done)
994 n--;
995 continue;
998 /* If this is an undefined symbol which was equated to another
999 symbol, then generate the reloc against the latter symbol
1000 rather than the former. */
1001 sym = fixp->fx_addsy;
1002 while (symbol_equated_reloc_p (sym))
1004 symbolS *n;
1006 /* We must avoid looping, as that can occur with a badly
1007 written program. */
1008 n = symbol_get_value_expression (sym)->X_add_symbol;
1009 if (n == sym)
1010 break;
1011 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
1012 sym = n;
1014 fixp->fx_addsy = sym;
1016 reloc = tc_gen_reloc (sec, fixp);
1018 for (j = 0; reloc[j]; j++)
1020 relocs[i++] = reloc[j];
1021 assert (i <= n);
1023 if (fixp->fx_where + fixp->fx_size
1024 > fixp->fx_frag->fr_fix + fixp->fx_frag->fr_offset)
1025 as_bad_where (fixp->fx_file, fixp->fx_line,
1026 _("internal error: fixup not contained within frag"));
1027 for (j = 0; reloc[j]; j++)
1029 s = bfd_install_relocation (stdoutput, reloc[j],
1030 fixp->fx_frag->fr_literal,
1031 fixp->fx_frag->fr_address,
1032 sec, &err);
1033 switch (s)
1035 case bfd_reloc_ok:
1036 break;
1037 case bfd_reloc_overflow:
1038 as_bad_where (fixp->fx_file, fixp->fx_line,
1039 _("relocation overflow"));
1040 break;
1041 case bfd_reloc_outofrange:
1042 as_bad_where (fixp->fx_file, fixp->fx_line,
1043 _("relocation out of range"));
1044 break;
1045 default:
1046 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1047 fixp->fx_file, fixp->fx_line, s);
1051 n = i;
1052 #endif
1054 #ifdef DEBUG4
1056 int i, j, nsyms;
1057 asymbol **sympp;
1058 sympp = bfd_get_outsymbols (stdoutput);
1059 nsyms = bfd_get_symcount (stdoutput);
1060 for (i = 0; i < n; i++)
1061 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1063 for (j = 0; j < nsyms; j++)
1064 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1065 break;
1066 if (j == nsyms)
1067 abort ();
1070 #endif
1072 if (n)
1073 bfd_set_reloc (stdoutput, sec, relocs, n);
1074 else
1075 bfd_set_section_flags (abfd, sec,
1076 (bfd_get_section_flags (abfd, sec)
1077 & (flagword) ~SEC_RELOC));
1079 #ifdef SET_SECTION_RELOCS
1080 SET_SECTION_RELOCS (sec, relocs, n);
1081 #endif
1083 #ifdef DEBUG3
1085 int i;
1086 arelent *r;
1087 asymbol *s;
1088 fprintf (stderr, "relocs for sec %s\n", sec->name);
1089 for (i = 0; i < n; i++)
1091 r = relocs[i];
1092 s = *r->sym_ptr_ptr;
1093 fprintf (stderr, " reloc %2d @%08x off %4x : sym %-10s addend %x\n",
1094 i, r, r->address, s->name, r->addend);
1097 #endif
1100 static void
1101 write_contents (bfd *abfd ATTRIBUTE_UNUSED,
1102 asection *sec,
1103 PTR xxx ATTRIBUTE_UNUSED)
1105 segment_info_type *seginfo = seg_info (sec);
1106 addressT offset = 0;
1107 fragS *f;
1109 /* Write out the frags. */
1110 if (seginfo == NULL
1111 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1112 return;
1114 for (f = seginfo->frchainP->frch_root;
1116 f = f->fr_next)
1118 int x;
1119 addressT fill_size;
1120 char *fill_literal;
1121 offsetT count;
1123 assert (f->fr_type == rs_fill);
1124 if (f->fr_fix)
1126 x = bfd_set_section_contents (stdoutput, sec,
1127 f->fr_literal, (file_ptr) offset,
1128 (bfd_size_type) f->fr_fix);
1129 if (!x)
1131 bfd_perror (stdoutput->filename);
1132 as_perror (_("FATAL: Can't write %s"), stdoutput->filename);
1133 exit (EXIT_FAILURE);
1135 offset += f->fr_fix;
1137 fill_literal = f->fr_literal + f->fr_fix;
1138 fill_size = f->fr_var;
1139 count = f->fr_offset;
1140 assert (count >= 0);
1141 if (fill_size && count)
1143 char buf[256];
1144 if (fill_size > sizeof (buf))
1146 /* Do it the old way. Can this ever happen? */
1147 while (count--)
1149 x = bfd_set_section_contents (stdoutput, sec,
1150 fill_literal,
1151 (file_ptr) offset,
1152 (bfd_size_type) fill_size);
1153 if (!x)
1155 bfd_perror (stdoutput->filename);
1156 as_perror (_("FATAL: Can't write %s"),
1157 stdoutput->filename);
1158 exit (EXIT_FAILURE);
1160 offset += fill_size;
1163 else
1165 /* Build a buffer full of fill objects and output it as
1166 often as necessary. This saves on the overhead of
1167 potentially lots of bfd_set_section_contents calls. */
1168 int n_per_buf, i;
1169 if (fill_size == 1)
1171 n_per_buf = sizeof (buf);
1172 memset (buf, *fill_literal, n_per_buf);
1174 else
1176 char *bufp;
1177 n_per_buf = sizeof (buf) / fill_size;
1178 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1179 memcpy (bufp, fill_literal, fill_size);
1181 for (; count > 0; count -= n_per_buf)
1183 n_per_buf = n_per_buf > count ? count : n_per_buf;
1184 x = bfd_set_section_contents
1185 (stdoutput, sec, buf, (file_ptr) offset,
1186 (bfd_size_type) n_per_buf * fill_size);
1187 if (!x)
1188 as_fatal (_("cannot write to output file"));
1189 offset += n_per_buf * fill_size;
1195 #endif
1197 #if defined(BFD_ASSEMBLER) || (!defined (BFD) && !defined(OBJ_AOUT))
1198 static void
1199 merge_data_into_text (void)
1201 #if defined(BFD_ASSEMBLER) || defined(MANY_SEGMENTS)
1202 seg_info (text_section)->frchainP->frch_last->fr_next =
1203 seg_info (data_section)->frchainP->frch_root;
1204 seg_info (text_section)->frchainP->frch_last =
1205 seg_info (data_section)->frchainP->frch_last;
1206 seg_info (data_section)->frchainP = 0;
1207 #else
1208 fixS *tmp;
1210 text_last_frag->fr_next = data_frag_root;
1211 text_last_frag = data_last_frag;
1212 data_last_frag = NULL;
1213 data_frag_root = NULL;
1214 if (text_fix_root)
1216 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
1217 tmp->fx_next = data_fix_root;
1218 text_fix_tail = data_fix_tail;
1220 else
1221 text_fix_root = data_fix_root;
1222 data_fix_root = NULL;
1223 #endif
1225 #endif /* BFD_ASSEMBLER || (! BFD && ! OBJ_AOUT) */
1227 #if !defined (BFD_ASSEMBLER) && !defined (BFD)
1228 static void
1229 relax_and_size_all_segments ()
1231 fragS *fragP;
1233 relax_segment (text_frag_root, SEG_TEXT);
1234 relax_segment (data_frag_root, SEG_DATA);
1235 relax_segment (bss_frag_root, SEG_BSS);
1237 /* Now the addresses of frags are correct within the segment. */
1238 know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
1239 H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
1240 text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
1242 /* Join the 2 segments into 1 huge segment.
1243 To do this, re-compute every rn_address in the SEG_DATA frags.
1244 Then join the data frags after the text frags.
1246 Determine a_data [length of data segment]. */
1247 if (data_frag_root)
1249 register relax_addressT slide;
1251 know ((text_last_frag->fr_type == rs_fill)
1252 && (text_last_frag->fr_offset == 0));
1254 H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
1255 data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
1256 slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
1257 #ifdef OBJ_BOUT
1258 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
1259 /* For b.out: If the data section has a strict alignment
1260 requirement, its load address in the .o file will be
1261 rounded up from the size of the text section. These
1262 two values are *not* the same! Similarly for the bss
1263 section.... */
1264 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
1265 #endif
1267 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
1268 fragP->fr_address += slide;
1270 know (text_last_frag != 0);
1271 text_last_frag->fr_next = data_frag_root;
1273 else
1275 H_SET_DATA_SIZE (&headers, 0);
1278 #ifdef OBJ_BOUT
1279 /* See above comments on b.out data section address. */
1281 addressT bss_vma;
1282 if (data_last_frag == 0)
1283 bss_vma = H_GET_TEXT_SIZE (&headers);
1284 else
1285 bss_vma = data_last_frag->fr_address;
1286 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
1287 bss_address_frag.fr_address = bss_vma;
1289 #else /* ! OBJ_BOUT */
1290 bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
1291 H_GET_DATA_SIZE (&headers));
1293 #endif /* ! OBJ_BOUT */
1295 /* Slide all the frags. */
1296 if (bss_frag_root)
1298 relax_addressT slide = bss_address_frag.fr_address;
1300 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
1301 fragP->fr_address += slide;
1304 if (bss_last_frag)
1305 H_SET_BSS_SIZE (&headers,
1306 bss_last_frag->fr_address - bss_frag_root->fr_address);
1307 else
1308 H_SET_BSS_SIZE (&headers, 0);
1310 #endif /* ! BFD_ASSEMBLER && ! BFD */
1312 #if defined (BFD_ASSEMBLER) || !defined (BFD)
1314 #ifdef BFD_ASSEMBLER
1315 static void
1316 set_symtab (void)
1318 int nsyms;
1319 asymbol **asympp;
1320 symbolS *symp;
1321 bfd_boolean result;
1322 extern PTR bfd_alloc (bfd *, bfd_size_type);
1324 /* Count symbols. We can't rely on a count made by the loop in
1325 write_object_file, because *_frob_file may add a new symbol or
1326 two. */
1327 nsyms = 0;
1328 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1329 nsyms++;
1331 if (nsyms)
1333 int i;
1334 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1336 asympp = (asymbol **) bfd_alloc (stdoutput, amt);
1337 symp = symbol_rootP;
1338 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1340 asympp[i] = symbol_get_bfdsym (symp);
1341 symbol_mark_written (symp);
1344 else
1345 asympp = 0;
1346 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1347 assert (result);
1348 symbol_table_frozen = 1;
1350 #endif
1352 /* Finish the subsegments. After every sub-segment, we fake an
1353 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1354 ".fill 0" because that is the kind of frag that requires least
1355 thought. ".align" frags like to have a following frag since that
1356 makes calculating their intended length trivial. */
1358 #ifndef SUB_SEGMENT_ALIGN
1359 #ifdef HANDLE_ALIGN
1360 /* The last subsegment gets an alignment corresponding to the alignment
1361 of the section. This allows proper nop-filling at the end of
1362 code-bearing sections. */
1363 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1364 (!(FRCHAIN)->frch_next || (FRCHAIN)->frch_next->frch_seg != (SEG) \
1365 ? get_recorded_alignment (SEG) : 0)
1366 #else
1367 #ifdef BFD_ASSEMBLER
1368 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1369 #else
1370 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 2
1371 #endif
1372 #endif
1373 #endif
1375 void
1376 subsegs_finish (void)
1378 struct frchain *frchainP;
1380 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
1382 int alignment = 0;
1384 subseg_set (frchainP->frch_seg, frchainP->frch_subseg);
1386 /* This now gets called even if we had errors. In that case,
1387 any alignment is meaningless, and, moreover, will look weird
1388 if we are generating a listing. */
1389 if (!had_errors ())
1391 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1392 #ifdef BFD_ASSEMBLER
1393 if ((bfd_get_section_flags (now_seg->owner, now_seg) & SEC_MERGE)
1394 && now_seg->entsize)
1396 unsigned int entsize = now_seg->entsize;
1397 int entalign = 0;
1399 while ((entsize & 1) == 0)
1401 ++entalign;
1402 entsize >>= 1;
1404 if (entalign > alignment)
1405 alignment = entalign;
1407 #endif
1410 if (subseg_text_p (now_seg))
1411 frag_align_code (alignment, 0);
1412 else
1413 frag_align (alignment, 0, 0);
1415 /* frag_align will have left a new frag.
1416 Use this last frag for an empty ".fill".
1418 For this segment ...
1419 Create a last frag. Do not leave a "being filled in frag". */
1420 frag_wane (frag_now);
1421 frag_now->fr_fix = 0;
1422 know (frag_now->fr_next == NULL);
1426 /* Write the object file. */
1428 void
1429 write_object_file (void)
1431 #if ! defined (BFD_ASSEMBLER) || ! defined (WORKING_DOT_WORD)
1432 fragS *fragP; /* Track along all frags. */
1433 #endif
1435 /* Do we really want to write it? */
1437 int n_warns, n_errs;
1438 n_warns = had_warnings ();
1439 n_errs = had_errors ();
1440 /* The -Z flag indicates that an object file should be generated,
1441 regardless of warnings and errors. */
1442 if (flag_always_generate_output)
1444 if (n_warns || n_errs)
1445 as_warn (_("%d error%s, %d warning%s, generating bad object file"),
1446 n_errs, n_errs == 1 ? "" : "s",
1447 n_warns, n_warns == 1 ? "" : "s");
1449 else
1451 if (n_errs)
1452 as_fatal (_("%d error%s, %d warning%s, no object file generated"),
1453 n_errs, n_errs == 1 ? "" : "s",
1454 n_warns, n_warns == 1 ? "" : "s");
1458 #ifdef OBJ_VMS
1459 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1460 a routine to check for the definition of the procedure "_main",
1461 and if so -- fix it up so that it can be program entry point. */
1462 vms_check_for_main ();
1463 #endif /* OBJ_VMS */
1465 /* From now on, we don't care about sub-segments. Build one frag chain
1466 for each segment. Linked thru fr_next. */
1468 #ifdef BFD_ASSEMBLER
1469 /* Remove the sections created by gas for its own purposes. */
1471 asection **seclist;
1472 int i;
1474 seclist = &stdoutput->sections;
1475 while (*seclist)
1477 if (*seclist == reg_section || *seclist == expr_section)
1479 bfd_section_list_remove (stdoutput, seclist);
1480 stdoutput->section_count--;
1482 else
1483 seclist = &(*seclist)->next;
1485 i = 0;
1486 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1489 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1490 #else
1491 remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
1492 remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
1493 remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
1494 #endif
1496 /* We have two segments. If user gave -R flag, then we must put the
1497 data frags into the text segment. Do this before relaxing so
1498 we know to take advantage of -R and make shorter addresses. */
1499 #if !defined (OBJ_AOUT) || defined (BFD_ASSEMBLER)
1500 if (flag_readonly_data_in_text)
1502 merge_data_into_text ();
1504 #endif
1506 #ifdef BFD_ASSEMBLER
1507 while (1)
1509 int changed;
1511 #ifndef WORKING_DOT_WORD
1512 /* We need to reset the markers in the broken word list and
1513 associated frags between calls to relax_segment (via
1514 relax_seg). Since the broken word list is global, we do it
1515 once per round, rather than locally in relax_segment for each
1516 segment. */
1517 struct broken_word *brokp;
1519 for (brokp = broken_words;
1520 brokp != (struct broken_word *) NULL;
1521 brokp = brokp->next_broken_word)
1523 brokp->added = 0;
1525 if (brokp->dispfrag != (fragS *) NULL
1526 && brokp->dispfrag->fr_type == rs_broken_word)
1527 brokp->dispfrag->fr_subtype = 0;
1529 #endif
1531 changed = 0;
1532 bfd_map_over_sections (stdoutput, relax_seg, &changed);
1533 if (!changed)
1534 break;
1537 /* Note - Most ports will use the default value of
1538 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
1539 local symbols to be resolved, removing their frag information.
1540 Some ports however, will not have finished relaxing all of
1541 their frags and will still need the local symbol frag
1542 information. These ports can set
1543 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
1544 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
1546 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
1547 #else
1548 relax_and_size_all_segments ();
1549 #endif /* BFD_ASSEMBLER */
1551 /* Relaxation has completed. Freeze all syms. */
1552 finalize_syms = 1;
1554 #ifdef md_post_relax_hook
1555 md_post_relax_hook;
1556 #endif
1558 #ifndef BFD_ASSEMBLER
1559 /* Crawl the symbol chain.
1561 For each symbol whose value depends on a frag, take the address of
1562 that frag and subsume it into the value of the symbol.
1563 After this, there is just one way to lookup a symbol value.
1564 Values are left in their final state for object file emission.
1565 We adjust the values of 'L' local symbols, even if we do
1566 not intend to emit them to the object file, because their values
1567 are needed for fix-ups.
1569 Unless we saw a -L flag, remove all symbols that begin with 'L'
1570 from the symbol chain. (They are still pointed to by the fixes.)
1572 Count the remaining symbols.
1573 Assign a symbol number to each symbol.
1574 Count the number of string-table chars we will emit.
1575 Put this info into the headers as appropriate. */
1576 know (zero_address_frag.fr_address == 0);
1577 string_byte_count = sizeof (string_byte_count);
1579 obj_crawl_symbol_chain (&headers);
1581 if (string_byte_count == sizeof (string_byte_count))
1582 string_byte_count = 0;
1584 H_SET_STRING_SIZE (&headers, string_byte_count);
1586 /* Addresses of frags now reflect addresses we use in the object file.
1587 Symbol values are correct.
1588 Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
1589 Also converting any machine-dependent frags using md_convert_frag(); */
1590 subseg_change (SEG_TEXT, 0);
1592 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1594 /* At this point we have linked all the frags into a single
1595 chain. However, cvt_frag_to_fill may call md_convert_frag
1596 which may call fix_new. We need to ensure that fix_new adds
1597 the fixup to the right section. */
1598 if (fragP == data_frag_root)
1599 subseg_change (SEG_DATA, 0);
1601 cvt_frag_to_fill (&headers, SEG_TEXT, fragP);
1603 /* Some assert macros don't work with # directives mixed in. */
1604 #ifndef NDEBUG
1605 if (!(fragP->fr_next == NULL
1606 #ifdef OBJ_BOUT
1607 || fragP->fr_next == data_frag_root
1608 #endif
1609 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
1610 == (fragP->fr_fix + fragP->fr_offset * fragP->fr_var))))
1611 abort ();
1612 #endif
1614 #endif /* ! BFD_ASSEMBLER */
1616 #ifndef WORKING_DOT_WORD
1618 struct broken_word *lie;
1619 struct broken_word **prevP;
1621 prevP = &broken_words;
1622 for (lie = broken_words; lie; lie = lie->next_broken_word)
1623 if (!lie->added)
1625 expressionS exp;
1627 subseg_change (lie->seg, lie->subseg);
1628 exp.X_op = O_subtract;
1629 exp.X_add_symbol = lie->add;
1630 exp.X_op_symbol = lie->sub;
1631 exp.X_add_number = lie->addnum;
1632 #ifdef BFD_ASSEMBLER
1633 #ifdef TC_CONS_FIX_NEW
1634 TC_CONS_FIX_NEW (lie->frag,
1635 lie->word_goes_here - lie->frag->fr_literal,
1636 2, &exp);
1637 #else
1638 fix_new_exp (lie->frag,
1639 lie->word_goes_here - lie->frag->fr_literal,
1640 2, &exp, 0, BFD_RELOC_16);
1641 #endif
1642 #else
1643 #if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
1644 fix_new_exp (lie->frag,
1645 lie->word_goes_here - lie->frag->fr_literal,
1646 2, &exp, 0, NO_RELOC);
1647 #else
1648 #ifdef TC_NS32K
1649 fix_new_ns32k_exp (lie->frag,
1650 lie->word_goes_here - lie->frag->fr_literal,
1651 2, &exp, 0, 0, 2, 0, 0);
1652 #else
1653 fix_new_exp (lie->frag,
1654 lie->word_goes_here - lie->frag->fr_literal,
1655 2, &exp, 0, 0);
1656 #endif /* TC_NS32K */
1657 #endif /* TC_SPARC|TC_A29K|NEED_FX_R_TYPE */
1658 #endif /* BFD_ASSEMBLER */
1659 *prevP = lie->next_broken_word;
1661 else
1662 prevP = &(lie->next_broken_word);
1664 for (lie = broken_words; lie;)
1666 struct broken_word *untruth;
1667 char *table_ptr;
1668 addressT table_addr;
1669 addressT from_addr, to_addr;
1670 int n, m;
1672 subseg_change (lie->seg, lie->subseg);
1673 fragP = lie->dispfrag;
1675 /* Find out how many broken_words go here. */
1676 n = 0;
1677 for (untruth = lie;
1678 untruth && untruth->dispfrag == fragP;
1679 untruth = untruth->next_broken_word)
1680 if (untruth->added == 1)
1681 n++;
1683 table_ptr = lie->dispfrag->fr_opcode;
1684 table_addr = (lie->dispfrag->fr_address
1685 + (table_ptr - lie->dispfrag->fr_literal));
1686 /* Create the jump around the long jumps. This is a short
1687 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1688 from_addr = table_addr;
1689 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1690 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1691 lie->add);
1692 table_ptr += md_short_jump_size;
1693 table_addr += md_short_jump_size;
1695 for (m = 0;
1696 lie && lie->dispfrag == fragP;
1697 m++, lie = lie->next_broken_word)
1699 if (lie->added == 2)
1700 continue;
1701 /* Patch the jump table. */
1702 /* This is the offset from ??? to table_ptr+0. */
1703 to_addr = table_addr - S_GET_VALUE (lie->sub);
1704 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1705 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_addr, lie);
1706 #endif
1707 md_number_to_chars (lie->word_goes_here, to_addr, 2);
1708 for (untruth = lie->next_broken_word;
1709 untruth && untruth->dispfrag == fragP;
1710 untruth = untruth->next_broken_word)
1712 if (untruth->use_jump == lie)
1713 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
1716 /* Install the long jump. */
1717 /* This is a long jump from table_ptr+0 to the final target. */
1718 from_addr = table_addr;
1719 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1720 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1721 lie->add);
1722 table_ptr += md_long_jump_size;
1723 table_addr += md_long_jump_size;
1727 #endif /* not WORKING_DOT_WORD */
1729 #ifndef BFD_ASSEMBLER
1730 #ifndef OBJ_VMS
1731 { /* not vms */
1732 char *the_object_file;
1733 long object_file_size;
1734 /* Scan every FixS performing fixups. We had to wait until now to
1735 do this because md_convert_frag() may have made some fixSs. */
1736 int trsize, drsize;
1738 subseg_change (SEG_TEXT, 0);
1739 trsize = md_reloc_size * fixup_segment (text_fix_root, SEG_TEXT);
1740 subseg_change (SEG_DATA, 0);
1741 drsize = md_reloc_size * fixup_segment (data_fix_root, SEG_DATA);
1742 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
1744 /* FIXME: Move this stuff into the pre-write-hook. */
1745 H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
1746 H_SET_ENTRY_POINT (&headers, 0);
1748 obj_pre_write_hook (&headers); /* Extra coff stuff. */
1750 object_file_size = H_GET_FILE_SIZE (&headers);
1751 next_object_file_charP = the_object_file = xmalloc (object_file_size);
1753 output_file_create (out_file_name);
1755 obj_header_append (&next_object_file_charP, &headers);
1757 know ((next_object_file_charP - the_object_file)
1758 == H_GET_HEADER_SIZE (&headers));
1760 /* Emit code. */
1761 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
1763 register long count;
1764 register char *fill_literal;
1765 register long fill_size;
1767 PROGRESS (1);
1768 know (fragP->fr_type == rs_fill);
1769 append (&next_object_file_charP, fragP->fr_literal,
1770 (unsigned long) fragP->fr_fix);
1771 fill_literal = fragP->fr_literal + fragP->fr_fix;
1772 fill_size = fragP->fr_var;
1773 know (fragP->fr_offset >= 0);
1775 for (count = fragP->fr_offset; count; count--)
1776 append (&next_object_file_charP, fill_literal,
1777 (unsigned long) fill_size);
1780 know ((next_object_file_charP - the_object_file)
1781 == (H_GET_HEADER_SIZE (&headers)
1782 + H_GET_TEXT_SIZE (&headers)
1783 + H_GET_DATA_SIZE (&headers)));
1785 /* Emit relocations. */
1786 obj_emit_relocations (&next_object_file_charP, text_fix_root,
1787 (relax_addressT) 0);
1788 know ((next_object_file_charP - the_object_file)
1789 == (H_GET_HEADER_SIZE (&headers)
1790 + H_GET_TEXT_SIZE (&headers)
1791 + H_GET_DATA_SIZE (&headers)
1792 + H_GET_TEXT_RELOCATION_SIZE (&headers)));
1793 #ifdef TC_I960
1794 /* Make addresses in data relocation directives relative to beginning of
1795 first data fragment, not end of last text fragment: alignment of the
1796 start of the data segment may place a gap between the segments. */
1797 obj_emit_relocations (&next_object_file_charP, data_fix_root,
1798 data0_frchainP->frch_root->fr_address);
1799 #else /* TC_I960 */
1800 obj_emit_relocations (&next_object_file_charP, data_fix_root,
1801 text_last_frag->fr_address);
1802 #endif /* TC_I960 */
1804 know ((next_object_file_charP - the_object_file)
1805 == (H_GET_HEADER_SIZE (&headers)
1806 + H_GET_TEXT_SIZE (&headers)
1807 + H_GET_DATA_SIZE (&headers)
1808 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1809 + H_GET_DATA_RELOCATION_SIZE (&headers)));
1811 /* Emit line number entries. */
1812 OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
1813 know ((next_object_file_charP - the_object_file)
1814 == (H_GET_HEADER_SIZE (&headers)
1815 + H_GET_TEXT_SIZE (&headers)
1816 + H_GET_DATA_SIZE (&headers)
1817 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1818 + H_GET_DATA_RELOCATION_SIZE (&headers)
1819 + H_GET_LINENO_SIZE (&headers)));
1821 /* Emit symbols. */
1822 obj_emit_symbols (&next_object_file_charP, symbol_rootP);
1823 know ((next_object_file_charP - the_object_file)
1824 == (H_GET_HEADER_SIZE (&headers)
1825 + H_GET_TEXT_SIZE (&headers)
1826 + H_GET_DATA_SIZE (&headers)
1827 + H_GET_TEXT_RELOCATION_SIZE (&headers)
1828 + H_GET_DATA_RELOCATION_SIZE (&headers)
1829 + H_GET_LINENO_SIZE (&headers)
1830 + H_GET_SYMBOL_TABLE_SIZE (&headers)));
1832 /* Emit strings. */
1833 if (string_byte_count > 0)
1834 obj_emit_strings (&next_object_file_charP);
1836 #ifdef BFD_HEADERS
1837 bfd_seek (stdoutput, (file_ptr) 0, 0);
1838 bfd_bwrite (the_object_file, (bfd_size_type) object_file_size, stdoutput);
1839 #else
1841 /* Write the data to the file. */
1842 output_file_append (the_object_file, object_file_size, out_file_name);
1843 free (the_object_file);
1844 #endif
1846 #else /* OBJ_VMS */
1847 /* Now do the VMS-dependent part of writing the object file. */
1848 vms_write_object_file (H_GET_TEXT_SIZE (&headers),
1849 H_GET_DATA_SIZE (&headers),
1850 H_GET_BSS_SIZE (&headers),
1851 text_frag_root, data_frag_root);
1852 #endif /* OBJ_VMS */
1853 #else /* BFD_ASSEMBLER */
1855 /* Resolve symbol values. This needs to be done before processing
1856 the relocations. */
1857 if (symbol_rootP)
1859 symbolS *symp;
1861 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1862 resolve_symbol_value (symp);
1864 resolve_local_symbol_values ();
1866 PROGRESS (1);
1868 #ifdef tc_frob_file_before_adjust
1869 tc_frob_file_before_adjust ();
1870 #endif
1871 #ifdef obj_frob_file_before_adjust
1872 obj_frob_file_before_adjust ();
1873 #endif
1875 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
1877 #ifdef tc_frob_file_before_fix
1878 tc_frob_file_before_fix ();
1879 #endif
1880 #ifdef obj_frob_file_before_fix
1881 obj_frob_file_before_fix ();
1882 #endif
1884 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
1886 /* Set up symbol table, and write it out. */
1887 if (symbol_rootP)
1889 symbolS *symp;
1891 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1893 int punt = 0;
1894 const char *name;
1896 if (symbol_mri_common_p (symp))
1898 if (S_IS_EXTERNAL (symp))
1899 as_bad (_("%s: global symbols not supported in common sections"),
1900 S_GET_NAME (symp));
1901 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1902 continue;
1905 name = S_GET_NAME (symp);
1906 if (name)
1908 const char *name2 =
1909 decode_local_label_name ((char *) S_GET_NAME (symp));
1910 /* They only differ if `name' is a fb or dollar local
1911 label name. */
1912 if (name2 != name && ! S_IS_DEFINED (symp))
1913 as_bad (_("local label `%s' is not defined"), name2);
1916 /* Do it again, because adjust_reloc_syms might introduce
1917 more symbols. They'll probably only be section symbols,
1918 but they'll still need to have the values computed. */
1919 resolve_symbol_value (symp);
1921 /* Skip symbols which were equated to undefined or common
1922 symbols. */
1923 if (symbol_equated_reloc_p (symp))
1925 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1926 continue;
1929 /* So far, common symbols have been treated like undefined symbols.
1930 Put them in the common section now. */
1931 if (S_IS_DEFINED (symp) == 0
1932 && S_GET_VALUE (symp) != 0)
1933 S_SET_SEGMENT (symp, bfd_com_section_ptr);
1934 #if 0
1935 printf ("symbol `%s'\n\t@%x: value=%d flags=%x seg=%s\n",
1936 S_GET_NAME (symp), symp,
1937 S_GET_VALUE (symp),
1938 symbol_get_bfdsym (symp)->flags,
1939 segment_name (S_GET_SEGMENT (symp)));
1940 #endif
1942 #ifdef obj_frob_symbol
1943 obj_frob_symbol (symp, punt);
1944 #endif
1945 #ifdef tc_frob_symbol
1946 if (! punt || symbol_used_in_reloc_p (symp))
1947 tc_frob_symbol (symp, punt);
1948 #endif
1950 /* If we don't want to keep this symbol, splice it out of
1951 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
1952 want section symbols. Otherwise, we skip local symbols
1953 and symbols that the frob_symbol macros told us to punt,
1954 but we keep such symbols if they are used in relocs. */
1955 if (symp == abs_section_sym
1956 || (! EMIT_SECTION_SYMBOLS
1957 && symbol_section_p (symp))
1958 /* Note that S_IS_EXTERN and S_IS_LOCAL are not always
1959 opposites. Sometimes the former checks flags and the
1960 latter examines the name... */
1961 || (!S_IS_EXTERN (symp)
1962 && (punt || S_IS_LOCAL (symp))
1963 && ! symbol_used_in_reloc_p (symp)))
1965 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1967 /* After symbol_remove, symbol_next(symp) still returns
1968 the one that came after it in the chain. So we don't
1969 need to do any extra cleanup work here. */
1970 continue;
1973 /* Make sure we really got a value for the symbol. */
1974 if (! symbol_resolved_p (symp))
1976 as_bad (_("can't resolve value for symbol `%s'"),
1977 S_GET_NAME (symp));
1978 symbol_mark_resolved (symp);
1981 /* Set the value into the BFD symbol. Up til now the value
1982 has only been kept in the gas symbolS struct. */
1983 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1987 PROGRESS (1);
1989 /* Now do any format-specific adjustments to the symbol table, such
1990 as adding file symbols. */
1991 #ifdef tc_adjust_symtab
1992 tc_adjust_symtab ();
1993 #endif
1994 #ifdef obj_adjust_symtab
1995 obj_adjust_symtab ();
1996 #endif
1998 /* Now that all the sizes are known, and contents correct, we can
1999 start writing to the file. */
2000 set_symtab ();
2002 /* If *_frob_file changes the symbol value at this point, it is
2003 responsible for moving the changed value into symp->bsym->value
2004 as well. Hopefully all symbol value changing can be done in
2005 *_frob_symbol. */
2006 #ifdef tc_frob_file
2007 tc_frob_file ();
2008 #endif
2009 #ifdef obj_frob_file
2010 obj_frob_file ();
2011 #endif
2013 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
2015 #ifdef tc_frob_file_after_relocs
2016 tc_frob_file_after_relocs ();
2017 #endif
2018 #ifdef obj_frob_file_after_relocs
2019 obj_frob_file_after_relocs ();
2020 #endif
2022 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
2023 #endif /* BFD_ASSEMBLER */
2025 #endif /* ! BFD */
2027 #ifdef TC_GENERIC_RELAX_TABLE
2029 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2031 long
2032 relax_frag (segT segment, fragS *fragP, long stretch)
2034 const relax_typeS *this_type;
2035 const relax_typeS *start_type;
2036 relax_substateT next_state;
2037 relax_substateT this_state;
2038 offsetT growth;
2039 offsetT aim;
2040 addressT target;
2041 addressT address;
2042 symbolS *symbolP;
2043 const relax_typeS *table;
2045 target = fragP->fr_offset;
2046 address = fragP->fr_address;
2047 table = TC_GENERIC_RELAX_TABLE;
2048 this_state = fragP->fr_subtype;
2049 start_type = this_type = table + this_state;
2050 symbolP = fragP->fr_symbol;
2052 if (symbolP)
2054 fragS *sym_frag;
2056 sym_frag = symbol_get_frag (symbolP);
2058 #ifndef DIFF_EXPR_OK
2059 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2060 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2061 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2062 || (S_GET_SEGMENT (symbolP) == SEG_BSS)
2063 || (S_GET_SEGMENT (symbolP) == SEG_TEXT));
2064 #endif
2065 know (sym_frag != NULL);
2066 #endif
2067 know (S_GET_SEGMENT (symbolP) != absolute_section
2068 || sym_frag == &zero_address_frag);
2069 target += S_GET_VALUE (symbolP);
2071 /* If frag has yet to be reached on this pass,
2072 assume it will move by STRETCH just as we did.
2073 If this is not so, it will be because some frag
2074 between grows, and that will force another pass. */
2076 if (stretch != 0
2077 && sym_frag->relax_marker != fragP->relax_marker
2078 && S_GET_SEGMENT (symbolP) == segment)
2080 target += stretch;
2084 aim = target - address - fragP->fr_fix;
2085 #ifdef TC_PCREL_ADJUST
2086 /* Currently only the ns32k family needs this. */
2087 aim += TC_PCREL_ADJUST (fragP);
2088 /* #else */
2089 /* This machine doesn't want to use pcrel_adjust.
2090 In that case, pcrel_adjust should be zero. */
2091 #if 0
2092 assert (fragP->fr_targ.ns32k.pcrel_adjust == 0);
2093 #endif
2094 #endif
2095 #ifdef md_prepare_relax_scan /* formerly called M68K_AIM_KLUDGE */
2096 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2097 #endif
2099 if (aim < 0)
2101 /* Look backwards. */
2102 for (next_state = this_type->rlx_more; next_state;)
2103 if (aim >= this_type->rlx_backward)
2104 next_state = 0;
2105 else
2107 /* Grow to next state. */
2108 this_state = next_state;
2109 this_type = table + this_state;
2110 next_state = this_type->rlx_more;
2113 else
2115 /* Look forwards. */
2116 for (next_state = this_type->rlx_more; next_state;)
2117 if (aim <= this_type->rlx_forward)
2118 next_state = 0;
2119 else
2121 /* Grow to next state. */
2122 this_state = next_state;
2123 this_type = table + this_state;
2124 next_state = this_type->rlx_more;
2128 growth = this_type->rlx_length - start_type->rlx_length;
2129 if (growth != 0)
2130 fragP->fr_subtype = this_state;
2131 return growth;
2134 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2136 /* Relax_align. Advance location counter to next address that has 'alignment'
2137 lowest order bits all 0s, return size of adjustment made. */
2138 static relax_addressT
2139 relax_align (register relax_addressT address, /* Address now. */
2140 register int alignment /* Alignment (binary). */)
2142 relax_addressT mask;
2143 relax_addressT new_address;
2145 mask = ~((~0) << alignment);
2146 new_address = (address + mask) & (~mask);
2147 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2148 if (linkrelax)
2149 /* We must provide lots of padding, so the linker can discard it
2150 when needed. The linker will not add extra space, ever. */
2151 new_address += (1 << alignment);
2152 #endif
2153 return (new_address - address);
2156 /* Now we have a segment, not a crowd of sub-segments, we can make
2157 fr_address values.
2159 Relax the frags.
2161 After this, all frags in this segment have addresses that are correct
2162 within the segment. Since segments live in different file addresses,
2163 these frag addresses may not be the same as final object-file
2164 addresses. */
2167 relax_segment (struct frag *segment_frag_root, segT segment)
2169 register struct frag *fragP;
2170 register relax_addressT address;
2171 int ret;
2173 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2174 know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
2175 #endif
2176 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2177 subseg_change (segment, 0);
2179 /* For each frag in segment: count and store (a 1st guess of)
2180 fr_address. */
2181 address = 0;
2182 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2184 fragP->relax_marker = 0;
2185 fragP->fr_address = address;
2186 address += fragP->fr_fix;
2188 switch (fragP->fr_type)
2190 case rs_fill:
2191 address += fragP->fr_offset * fragP->fr_var;
2192 break;
2194 case rs_align:
2195 case rs_align_code:
2196 case rs_align_test:
2198 addressT offset = relax_align (address, (int) fragP->fr_offset);
2200 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2201 offset = 0;
2203 if (offset % fragP->fr_var != 0)
2205 as_bad_where (fragP->fr_file, fragP->fr_line,
2206 _("alignment padding (%lu bytes) not a multiple of %ld"),
2207 (unsigned long) offset, (long) fragP->fr_var);
2208 offset -= (offset % fragP->fr_var);
2211 address += offset;
2213 break;
2215 case rs_org:
2216 case rs_space:
2217 /* Assume .org is nugatory. It will grow with 1st relax. */
2218 break;
2220 case rs_machine_dependent:
2221 /* If fr_symbol is an expression, this call to
2222 resolve_symbol_value sets up the correct segment, which will
2223 likely be needed in md_estimate_size_before_relax. */
2224 if (fragP->fr_symbol)
2225 resolve_symbol_value (fragP->fr_symbol);
2227 address += md_estimate_size_before_relax (fragP, segment);
2228 break;
2230 #ifndef WORKING_DOT_WORD
2231 /* Broken words don't concern us yet. */
2232 case rs_broken_word:
2233 break;
2234 #endif
2236 case rs_leb128:
2237 /* Initial guess is always 1; doing otherwise can result in
2238 stable solutions that are larger than the minimum. */
2239 address += fragP->fr_offset = 1;
2240 break;
2242 case rs_cfa:
2243 address += eh_frame_estimate_size_before_relax (fragP);
2244 break;
2246 case rs_dwarf2dbg:
2247 address += dwarf2dbg_estimate_size_before_relax (fragP);
2248 break;
2250 default:
2251 BAD_CASE (fragP->fr_type);
2252 break;
2256 /* Do relax(). */
2258 offsetT stretch; /* May be any size, 0 or negative. */
2259 /* Cumulative number of addresses we have relaxed this pass.
2260 We may have relaxed more than one address. */
2261 int stretched; /* Have we stretched on this pass? */
2262 /* This is 'cuz stretch may be zero, when, in fact some piece of code
2263 grew, and another shrank. If a branch instruction doesn't fit anymore,
2264 we could be scrod. */
2268 stretch = 0;
2269 stretched = 0;
2271 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2273 offsetT growth = 0;
2274 addressT was_address;
2275 offsetT offset;
2276 symbolS *symbolP;
2278 fragP->relax_marker ^= 1;
2279 was_address = fragP->fr_address;
2280 address = fragP->fr_address += stretch;
2281 symbolP = fragP->fr_symbol;
2282 offset = fragP->fr_offset;
2284 switch (fragP->fr_type)
2286 case rs_fill: /* .fill never relaxes. */
2287 growth = 0;
2288 break;
2290 #ifndef WORKING_DOT_WORD
2291 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2292 for it I do not want to write it. I do not want to have
2293 anything to do with it. This is not the proper way to
2294 implement this misfeature. */
2295 case rs_broken_word:
2297 struct broken_word *lie;
2298 struct broken_word *untruth;
2300 /* Yes this is ugly (storing the broken_word pointer
2301 in the symbol slot). Still, this whole chunk of
2302 code is ugly, and I don't feel like doing anything
2303 about it. Think of it as stubbornness in action. */
2304 growth = 0;
2305 for (lie = (struct broken_word *) (fragP->fr_symbol);
2306 lie && lie->dispfrag == fragP;
2307 lie = lie->next_broken_word)
2310 if (lie->added)
2311 continue;
2313 offset = (S_GET_VALUE (lie->add)
2314 + lie->addnum
2315 - S_GET_VALUE (lie->sub));
2316 if (offset <= -32768 || offset >= 32767)
2318 if (flag_warn_displacement)
2320 char buf[50];
2321 sprint_value (buf, (addressT) lie->addnum);
2322 as_warn_where (fragP->fr_file, fragP->fr_line,
2323 _(".word %s-%s+%s didn't fit"),
2324 S_GET_NAME (lie->add),
2325 S_GET_NAME (lie->sub),
2326 buf);
2328 lie->added = 1;
2329 if (fragP->fr_subtype == 0)
2331 fragP->fr_subtype++;
2332 growth += md_short_jump_size;
2334 for (untruth = lie->next_broken_word;
2335 untruth && untruth->dispfrag == lie->dispfrag;
2336 untruth = untruth->next_broken_word)
2337 if ((symbol_get_frag (untruth->add)
2338 == symbol_get_frag (lie->add))
2339 && (S_GET_VALUE (untruth->add)
2340 == S_GET_VALUE (lie->add)))
2342 untruth->added = 2;
2343 untruth->use_jump = lie;
2345 growth += md_long_jump_size;
2349 break;
2350 } /* case rs_broken_word */
2351 #endif
2352 case rs_align:
2353 case rs_align_code:
2354 case rs_align_test:
2356 addressT oldoff, newoff;
2358 oldoff = relax_align (was_address + fragP->fr_fix,
2359 (int) offset);
2360 newoff = relax_align (address + fragP->fr_fix,
2361 (int) offset);
2363 if (fragP->fr_subtype != 0)
2365 if (oldoff > fragP->fr_subtype)
2366 oldoff = 0;
2367 if (newoff > fragP->fr_subtype)
2368 newoff = 0;
2371 growth = newoff - oldoff;
2373 break;
2375 case rs_org:
2377 addressT target = offset;
2378 addressT after;
2380 if (symbolP)
2382 #if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
2383 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2384 || (S_GET_SEGMENT (symbolP) == SEG_DATA)
2385 || (S_GET_SEGMENT (symbolP) == SEG_TEXT)
2386 || S_GET_SEGMENT (symbolP) == SEG_BSS);
2387 know (symbolP->sy_frag);
2388 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE)
2389 || (symbolP->sy_frag == &zero_address_frag));
2390 #endif
2391 /* Convert from an actual address to an octet offset
2392 into the section. Here it is assumed that the
2393 section's VMA is zero, and can omit subtracting it
2394 from the symbol's value to get the address offset. */
2395 know (S_GET_SECTION (symbolP)->vma == 0);
2396 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2399 know (fragP->fr_next);
2400 after = fragP->fr_next->fr_address;
2401 growth = target - after;
2402 if (growth < 0)
2404 /* Growth may be negative, but variable part of frag
2405 cannot have fewer than 0 chars. That is, we can't
2406 .org backwards. */
2407 as_bad_where (fragP->fr_file, fragP->fr_line,
2408 _("attempt to move .org backwards"));
2410 /* We've issued an error message. Change the
2411 frag to avoid cascading errors. */
2412 fragP->fr_type = rs_align;
2413 fragP->fr_subtype = 0;
2414 fragP->fr_offset = 0;
2415 fragP->fr_fix = after - was_address;
2416 growth = stretch;
2419 /* This is an absolute growth factor */
2420 growth -= stretch;
2421 break;
2424 case rs_space:
2425 growth = 0;
2426 if (symbolP)
2428 offsetT amount;
2430 amount = S_GET_VALUE (symbolP);
2431 if (S_GET_SEGMENT (symbolP) != absolute_section
2432 || S_IS_COMMON (symbolP)
2433 || ! S_IS_DEFINED (symbolP))
2435 as_bad_where (fragP->fr_file, fragP->fr_line,
2436 _(".space specifies non-absolute value"));
2437 /* Prevent repeat of this error message. */
2438 fragP->fr_symbol = 0;
2440 else if (amount < 0)
2442 as_warn_where (fragP->fr_file, fragP->fr_line,
2443 _(".space or .fill with negative value, ignored"));
2444 fragP->fr_symbol = 0;
2446 else
2447 growth = (was_address + fragP->fr_fix + amount
2448 - fragP->fr_next->fr_address);
2450 break;
2452 case rs_machine_dependent:
2453 #ifdef md_relax_frag
2454 growth = md_relax_frag (segment, fragP, stretch);
2455 #else
2456 #ifdef TC_GENERIC_RELAX_TABLE
2457 /* The default way to relax a frag is to look through
2458 TC_GENERIC_RELAX_TABLE. */
2459 growth = relax_frag (segment, fragP, stretch);
2460 #endif /* TC_GENERIC_RELAX_TABLE */
2461 #endif
2462 break;
2464 case rs_leb128:
2466 valueT value;
2467 offsetT size;
2469 value = resolve_symbol_value (fragP->fr_symbol);
2470 size = sizeof_leb128 (value, fragP->fr_subtype);
2471 growth = size - fragP->fr_offset;
2472 fragP->fr_offset = size;
2474 break;
2476 case rs_cfa:
2477 growth = eh_frame_relax_frag (fragP);
2478 break;
2480 case rs_dwarf2dbg:
2481 growth = dwarf2dbg_relax_frag (fragP);
2482 break;
2484 default:
2485 BAD_CASE (fragP->fr_type);
2486 break;
2488 if (growth)
2490 stretch += growth;
2491 stretched = 1;
2493 } /* For each frag in the segment. */
2495 while (stretched); /* Until nothing further to relax. */
2496 } /* do_relax */
2498 ret = 0;
2499 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2500 if (fragP->last_fr_address != fragP->fr_address)
2502 fragP->last_fr_address = fragP->fr_address;
2503 ret = 1;
2505 return ret;
2508 #if defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS))
2510 /* fixup_segment()
2512 Go through all the fixS's in a segment and see which ones can be
2513 handled now. (These consist of fixS where we have since discovered
2514 the value of a symbol, or the address of the frag involved.)
2515 For each one, call md_apply_fix3 to put the fix into the frag data.
2517 Result is a count of how many relocation structs will be needed to
2518 handle the remaining fixS's that we couldn't completely handle here.
2519 These will be output later by emit_relocations(). */
2521 static long
2522 fixup_segment (fixS *fixP, segT this_segment)
2524 long seg_reloc_count = 0;
2525 valueT add_number;
2526 fragS *fragP;
2527 segT add_symbol_segment = absolute_section;
2529 if (fixP != NULL && abs_section_sym == NULL)
2531 #ifndef BFD_ASSEMBLER
2532 abs_section_sym = &abs_symbol;
2533 #else
2534 abs_section_sym = section_symbol (absolute_section);
2535 #endif
2538 /* If the linker is doing the relaxing, we must not do any fixups.
2540 Well, strictly speaking that's not true -- we could do any that
2541 are PC-relative and don't cross regions that could change size.
2542 And for the i960 we might be able to turn callx/callj into bal
2543 anyways in cases where we know the maximum displacement. */
2544 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
2546 for (; fixP; fixP = fixP->fx_next)
2547 if (!fixP->fx_done)
2549 if (fixP->fx_addsy == NULL)
2551 /* There was no symbol required by this relocation.
2552 However, BFD doesn't really handle relocations
2553 without symbols well. So fake up a local symbol in
2554 the absolute section. */
2555 fixP->fx_addsy = abs_section_sym;
2557 symbol_mark_used_in_reloc (fixP->fx_addsy);
2558 if (fixP->fx_subsy != NULL)
2559 symbol_mark_used_in_reloc (fixP->fx_subsy);
2560 seg_reloc_count++;
2562 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2563 return seg_reloc_count;
2566 for (; fixP; fixP = fixP->fx_next)
2568 #ifdef DEBUG5
2569 fprintf (stderr, "\nprocessing fixup:\n");
2570 print_fixup (fixP);
2571 #endif
2573 fragP = fixP->fx_frag;
2574 know (fragP);
2575 #ifdef TC_VALIDATE_FIX
2576 TC_VALIDATE_FIX (fixP, this_segment, skip);
2577 #endif
2578 add_number = fixP->fx_offset;
2580 if (fixP->fx_addsy != NULL
2581 && symbol_mri_common_p (fixP->fx_addsy))
2583 know (fixP->fx_addsy->sy_value.X_op == O_symbol);
2584 add_number += S_GET_VALUE (fixP->fx_addsy);
2585 fixP->fx_offset = add_number;
2586 fixP->fx_addsy
2587 = symbol_get_value_expression (fixP->fx_addsy)->X_add_symbol;
2590 if (fixP->fx_addsy != NULL)
2591 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
2593 if (fixP->fx_subsy != NULL)
2595 segT sub_symbol_segment;
2596 resolve_symbol_value (fixP->fx_subsy);
2597 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
2598 if (fixP->fx_addsy != NULL
2599 && sub_symbol_segment == add_symbol_segment
2600 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
2602 add_number += S_GET_VALUE (fixP->fx_addsy);
2603 add_number -= S_GET_VALUE (fixP->fx_subsy);
2604 fixP->fx_offset = add_number;
2605 fixP->fx_addsy = NULL;
2606 fixP->fx_subsy = NULL;
2607 #ifdef TC_M68K
2608 /* See the comment below about 68k weirdness. */
2609 fixP->fx_pcrel = 0;
2610 #endif
2612 else if (sub_symbol_segment == absolute_section
2613 && !TC_FORCE_RELOCATION_SUB_ABS (fixP))
2615 add_number -= S_GET_VALUE (fixP->fx_subsy);
2616 fixP->fx_offset = add_number;
2617 fixP->fx_subsy = NULL;
2619 else if (sub_symbol_segment == this_segment
2620 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP))
2622 add_number -= S_GET_VALUE (fixP->fx_subsy);
2623 fixP->fx_offset = (add_number + fixP->fx_dot_value
2624 + fixP->fx_frag->fr_address);
2626 /* Make it pc-relative. If the back-end code has not
2627 selected a pc-relative reloc, cancel the adjustment
2628 we do later on all pc-relative relocs. */
2629 if (0
2630 #ifdef TC_M68K
2631 /* Do this for m68k even if it's already described
2632 as pc-relative. On the m68k, an operand of
2633 "pc@(foo-.-2)" should address "foo" in a
2634 pc-relative mode. */
2635 || 1
2636 #endif
2637 || !fixP->fx_pcrel)
2638 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
2639 fixP->fx_subsy = NULL;
2640 fixP->fx_pcrel = 1;
2642 else if (!TC_VALIDATE_FIX_SUB (fixP))
2644 as_bad_where (fixP->fx_file, fixP->fx_line,
2645 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
2646 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
2647 segment_name (add_symbol_segment),
2648 S_GET_NAME (fixP->fx_subsy),
2649 segment_name (sub_symbol_segment));
2653 if (fixP->fx_addsy)
2655 if (add_symbol_segment == this_segment
2656 && !TC_FORCE_RELOCATION_LOCAL (fixP))
2658 /* This fixup was made when the symbol's segment was
2659 SEG_UNKNOWN, but it is now in the local segment.
2660 So we know how to do the address without relocation. */
2661 add_number += S_GET_VALUE (fixP->fx_addsy);
2662 fixP->fx_offset = add_number;
2663 if (fixP->fx_pcrel)
2664 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
2665 fixP->fx_addsy = NULL;
2666 fixP->fx_pcrel = 0;
2668 else if (add_symbol_segment == absolute_section
2669 && !TC_FORCE_RELOCATION_ABS (fixP))
2671 add_number += S_GET_VALUE (fixP->fx_addsy);
2672 fixP->fx_offset = add_number;
2673 fixP->fx_addsy = NULL;
2675 else if (add_symbol_segment != undefined_section
2676 #ifdef BFD_ASSEMBLER
2677 && ! bfd_is_com_section (add_symbol_segment)
2678 #endif
2679 && MD_APPLY_SYM_VALUE (fixP))
2680 add_number += S_GET_VALUE (fixP->fx_addsy);
2683 if (fixP->fx_pcrel)
2685 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
2686 if (!fixP->fx_done && fixP->fx_addsy == NULL)
2688 /* There was no symbol required by this relocation.
2689 However, BFD doesn't really handle relocations
2690 without symbols well. So fake up a local symbol in
2691 the absolute section. */
2692 fixP->fx_addsy = abs_section_sym;
2696 if (!fixP->fx_done)
2697 md_apply_fix3 (fixP, &add_number, this_segment);
2699 if (!fixP->fx_done)
2701 ++seg_reloc_count;
2702 if (fixP->fx_addsy == NULL)
2703 fixP->fx_addsy = abs_section_sym;
2704 symbol_mark_used_in_reloc (fixP->fx_addsy);
2705 if (fixP->fx_subsy != NULL)
2706 symbol_mark_used_in_reloc (fixP->fx_subsy);
2709 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
2711 if (fixP->fx_size < sizeof (valueT))
2713 valueT mask;
2715 mask = 0;
2716 mask--; /* Set all bits to one. */
2717 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
2718 if ((add_number & mask) != 0 && (add_number & mask) != mask)
2720 char buf[50], buf2[50];
2721 sprint_value (buf, fragP->fr_address + fixP->fx_where);
2722 if (add_number > 1000)
2723 sprint_value (buf2, add_number);
2724 else
2725 sprintf (buf2, "%ld", (long) add_number);
2726 as_bad_where (fixP->fx_file, fixP->fx_line,
2727 _("value of %s too large for field of %d bytes at %s"),
2728 buf2, fixP->fx_size, buf);
2729 } /* Generic error checking. */
2731 #ifdef WARN_SIGNED_OVERFLOW_WORD
2732 /* Warn if a .word value is too large when treated as a signed
2733 number. We already know it is not too negative. This is to
2734 catch over-large switches generated by gcc on the 68k. */
2735 if (!flag_signed_overflow_ok
2736 && fixP->fx_size == 2
2737 && add_number > 0x7fff)
2738 as_bad_where (fixP->fx_file, fixP->fx_line,
2739 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
2740 (long) add_number,
2741 (long) (fragP->fr_address + fixP->fx_where));
2742 #endif
2743 } /* Not a bit fix. */
2745 #ifdef TC_VALIDATE_FIX
2746 skip: ATTRIBUTE_UNUSED_LABEL
2748 #endif
2749 #ifdef DEBUG5
2750 fprintf (stderr, "result:\n");
2751 print_fixup (fixP);
2752 #endif
2753 } /* For each fixS in this segment. */
2755 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
2756 return seg_reloc_count;
2759 #endif /* defined (BFD_ASSEMBLER) || (!defined (BFD) && !defined (OBJ_VMS)) */
2761 void
2762 number_to_chars_bigendian (char *buf, valueT val, int n)
2764 if (n <= 0)
2765 abort ();
2766 while (n--)
2768 buf[n] = val & 0xff;
2769 val >>= 8;
2773 void
2774 number_to_chars_littleendian (char *buf, valueT val, int n)
2776 if (n <= 0)
2777 abort ();
2778 while (n--)
2780 *buf++ = val & 0xff;
2781 val >>= 8;
2785 void
2786 write_print_statistics (FILE *file)
2788 fprintf (file, "fixups: %d\n", n_fixups);
2791 /* For debugging. */
2792 extern int indent_level;
2794 void
2795 print_fixup (fixS *fixp)
2797 indent_level = 1;
2798 fprintf (stderr, "fix %lx %s:%d", (long) fixp, fixp->fx_file, fixp->fx_line);
2799 if (fixp->fx_pcrel)
2800 fprintf (stderr, " pcrel");
2801 if (fixp->fx_pcrel_adjust)
2802 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2803 if (fixp->fx_im_disp)
2805 #ifdef TC_NS32K
2806 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2807 #else
2808 fprintf (stderr, " im_disp");
2809 #endif
2811 if (fixp->fx_tcbit)
2812 fprintf (stderr, " tcbit");
2813 if (fixp->fx_done)
2814 fprintf (stderr, " done");
2815 fprintf (stderr, "\n size=%d frag=%lx where=%ld offset=%lx addnumber=%lx",
2816 fixp->fx_size, (long) fixp->fx_frag, (long) fixp->fx_where,
2817 (long) fixp->fx_offset, (long) fixp->fx_addnumber);
2818 #ifdef BFD_ASSEMBLER
2819 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2820 fixp->fx_r_type);
2821 #else
2822 #ifdef NEED_FX_R_TYPE
2823 fprintf (stderr, " r_type=%d", fixp->fx_r_type);
2824 #endif
2825 #endif
2826 if (fixp->fx_addsy)
2828 fprintf (stderr, "\n +<");
2829 print_symbol_value_1 (stderr, fixp->fx_addsy);
2830 fprintf (stderr, ">");
2832 if (fixp->fx_subsy)
2834 fprintf (stderr, "\n -<");
2835 print_symbol_value_1 (stderr, fixp->fx_subsy);
2836 fprintf (stderr, ">");
2838 fprintf (stderr, "\n");
2839 #ifdef TC_FIX_DATA_PRINT
2840 TC_FIX_DATA_PRINT (stderr, fixp);
2841 #endif