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[binutils.git] / gas / write.c
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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, 2005, 2006, 2007, 2008, 2009,
4 2010 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 3, 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, 51 Franklin Street - Fifth Floor, Boston, MA
21 02110-1301, 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"
30 #include "libbfd.h"
31 #include "compress-debug.h"
33 #ifndef TC_ADJUST_RELOC_COUNT
34 #define TC_ADJUST_RELOC_COUNT(FIX, COUNT)
35 #endif
37 #ifndef TC_FORCE_RELOCATION
38 #define TC_FORCE_RELOCATION(FIX) \
39 (generic_force_reloc (FIX))
40 #endif
42 #ifndef TC_FORCE_RELOCATION_ABS
43 #define TC_FORCE_RELOCATION_ABS(FIX) \
44 (TC_FORCE_RELOCATION (FIX))
45 #endif
47 #ifndef TC_FORCE_RELOCATION_LOCAL
48 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
49 (!(FIX)->fx_pcrel \
50 || TC_FORCE_RELOCATION (FIX))
51 #endif
53 #ifndef TC_FORCE_RELOCATION_SUB_SAME
54 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
55 (! SEG_NORMAL (SEG))
56 #endif
58 #ifndef md_register_arithmetic
59 # define md_register_arithmetic 1
60 #endif
62 #ifndef TC_FORCE_RELOCATION_SUB_ABS
63 #define TC_FORCE_RELOCATION_SUB_ABS(FIX, SEG) \
64 (!md_register_arithmetic && (SEG) == reg_section)
65 #endif
67 #ifndef TC_FORCE_RELOCATION_SUB_LOCAL
68 #ifdef DIFF_EXPR_OK
69 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) \
70 (!md_register_arithmetic && (SEG) == reg_section)
71 #else
72 #define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) 1
73 #endif
74 #endif
76 #ifndef TC_VALIDATE_FIX_SUB
77 #ifdef UNDEFINED_DIFFERENCE_OK
78 /* The PA needs this for PIC code generation. */
79 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
80 (md_register_arithmetic || (SEG) != reg_section)
81 #else
82 #define TC_VALIDATE_FIX_SUB(FIX, SEG) \
83 ((md_register_arithmetic || (SEG) != reg_section) \
84 && ((FIX)->fx_r_type == BFD_RELOC_GPREL32 \
85 || (FIX)->fx_r_type == BFD_RELOC_GPREL16))
86 #endif
87 #endif
89 #ifndef TC_LINKRELAX_FIXUP
90 #define TC_LINKRELAX_FIXUP(SEG) 1
91 #endif
93 #ifndef MD_APPLY_SYM_VALUE
94 #define MD_APPLY_SYM_VALUE(FIX) 1
95 #endif
97 #ifndef TC_FINALIZE_SYMS_BEFORE_SIZE_SEG
98 #define TC_FINALIZE_SYMS_BEFORE_SIZE_SEG 1
99 #endif
101 #ifndef MD_PCREL_FROM_SECTION
102 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from (FIX)
103 #endif
105 #ifndef TC_FAKE_LABEL
106 #define TC_FAKE_LABEL(NAME) (strcmp ((NAME), FAKE_LABEL_NAME) == 0)
107 #endif
109 /* Positive values of TC_FX_SIZE_SLACK allow a target to define
110 fixups that far past the end of a frag. Having such fixups
111 is of course most most likely a bug in setting fx_size correctly.
112 A negative value disables the fixup check entirely, which is
113 appropriate for something like the Renesas / SuperH SH_COUNT
114 reloc. */
115 #ifndef TC_FX_SIZE_SLACK
116 #define TC_FX_SIZE_SLACK(FIX) 0
117 #endif
119 /* Used to control final evaluation of expressions. */
120 int finalize_syms = 0;
122 int symbol_table_frozen;
124 symbolS *abs_section_sym;
126 /* Remember the value of dot when parsing expressions. */
127 addressT dot_value;
129 /* Relocs generated by ".reloc" pseudo. */
130 struct reloc_list* reloc_list;
132 void print_fixup (fixS *);
134 /* We generally attach relocs to frag chains. However, after we have
135 chained these all together into a segment, any relocs we add after
136 that must be attached to a segment. This will include relocs added
137 in md_estimate_size_for_relax, for example. */
138 static int frags_chained = 0;
140 static int n_fixups;
142 #define RELOC_ENUM enum bfd_reloc_code_real
144 /* Create a fixS in obstack 'notes'. */
146 static fixS *
147 fix_new_internal (fragS *frag, /* Which frag? */
148 int where, /* Where in that frag? */
149 int size, /* 1, 2, or 4 usually. */
150 symbolS *add_symbol, /* X_add_symbol. */
151 symbolS *sub_symbol, /* X_op_symbol. */
152 offsetT offset, /* X_add_number. */
153 int pcrel, /* TRUE if PC-relative relocation. */
154 RELOC_ENUM r_type ATTRIBUTE_UNUSED /* Relocation type. */,
155 int at_beginning) /* Add to the start of the list? */
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_dot_value = dot_value;
176 fixP->fx_pcrel = pcrel;
177 fixP->fx_r_type = r_type;
178 fixP->fx_im_disp = 0;
179 fixP->fx_pcrel_adjust = 0;
180 fixP->fx_bit_fixP = 0;
181 fixP->fx_addnumber = 0;
182 fixP->fx_tcbit = 0;
183 fixP->fx_tcbit2 = 0;
184 fixP->fx_done = 0;
185 fixP->fx_no_overflow = 0;
186 fixP->fx_signed = 0;
188 #ifdef USING_CGEN
189 fixP->fx_cgen.insn = NULL;
190 fixP->fx_cgen.opinfo = 0;
191 #endif
193 #ifdef TC_FIX_TYPE
194 TC_INIT_FIX_DATA (fixP);
195 #endif
197 as_where (&fixP->fx_file, &fixP->fx_line);
201 fixS **seg_fix_rootP = (frags_chained
202 ? &seg_info (now_seg)->fix_root
203 : &frchain_now->fix_root);
204 fixS **seg_fix_tailP = (frags_chained
205 ? &seg_info (now_seg)->fix_tail
206 : &frchain_now->fix_tail);
208 if (at_beginning)
210 fixP->fx_next = *seg_fix_rootP;
211 *seg_fix_rootP = fixP;
212 if (fixP->fx_next == NULL)
213 *seg_fix_tailP = fixP;
215 else
217 fixP->fx_next = NULL;
218 if (*seg_fix_tailP)
219 (*seg_fix_tailP)->fx_next = fixP;
220 else
221 *seg_fix_rootP = fixP;
222 *seg_fix_tailP = fixP;
226 return fixP;
229 /* Create a fixup relative to a symbol (plus a constant). */
231 fixS *
232 fix_new (fragS *frag, /* Which frag? */
233 int where, /* Where in that frag? */
234 int size, /* 1, 2, or 4 usually. */
235 symbolS *add_symbol, /* X_add_symbol. */
236 offsetT offset, /* X_add_number. */
237 int pcrel, /* TRUE if PC-relative relocation. */
238 RELOC_ENUM r_type /* Relocation type. */)
240 return fix_new_internal (frag, where, size, add_symbol,
241 (symbolS *) NULL, offset, pcrel, r_type, FALSE);
244 /* Create a fixup for an expression. Currently we only support fixups
245 for difference expressions. That is itself more than most object
246 file formats support anyhow. */
248 fixS *
249 fix_new_exp (fragS *frag, /* Which frag? */
250 int where, /* Where in that frag? */
251 int size, /* 1, 2, or 4 usually. */
252 expressionS *exp, /* Expression. */
253 int pcrel, /* TRUE if PC-relative relocation. */
254 RELOC_ENUM r_type /* Relocation type. */)
256 symbolS *add = NULL;
257 symbolS *sub = NULL;
258 offsetT off = 0;
260 switch (exp->X_op)
262 case O_absent:
263 break;
265 case O_register:
266 as_bad (_("register value used as expression"));
267 break;
269 case O_add:
270 /* This comes up when _GLOBAL_OFFSET_TABLE_+(.-L0) is read, if
271 the difference expression cannot immediately be reduced. */
273 symbolS *stmp = make_expr_symbol (exp);
275 exp->X_op = O_symbol;
276 exp->X_op_symbol = 0;
277 exp->X_add_symbol = stmp;
278 exp->X_add_number = 0;
280 return fix_new_exp (frag, where, size, exp, pcrel, r_type);
283 case O_symbol_rva:
284 add = exp->X_add_symbol;
285 off = exp->X_add_number;
286 r_type = BFD_RELOC_RVA;
287 break;
289 case O_uminus:
290 sub = exp->X_add_symbol;
291 off = exp->X_add_number;
292 break;
294 case O_subtract:
295 sub = exp->X_op_symbol;
296 /* Fall through. */
297 case O_symbol:
298 add = exp->X_add_symbol;
299 /* Fall through. */
300 case O_constant:
301 off = exp->X_add_number;
302 break;
304 default:
305 add = make_expr_symbol (exp);
306 break;
309 return fix_new_internal (frag, where, size, add, sub, off, pcrel,
310 r_type, FALSE);
313 /* Create a fixup at the beginning of FRAG. The arguments are the same
314 as for fix_new, except that WHERE is implicitly 0. */
316 fixS *
317 fix_at_start (fragS *frag, int size, symbolS *add_symbol,
318 offsetT offset, int pcrel, RELOC_ENUM r_type)
320 return fix_new_internal (frag, 0, size, add_symbol,
321 (symbolS *) NULL, offset, pcrel, r_type, TRUE);
324 /* Generic function to determine whether a fixup requires a relocation. */
326 generic_force_reloc (fixS *fix)
328 if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
329 || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
330 return 1;
332 if (fix->fx_addsy == NULL)
333 return 0;
335 return S_FORCE_RELOC (fix->fx_addsy, fix->fx_subsy == NULL);
338 /* Append a string onto another string, bumping the pointer along. */
339 void
340 append (char **charPP, char *fromP, 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 /* This routine records the largest alignment seen for each segment.
351 If the beginning of the segment is aligned on the worst-case
352 boundary, all of the other alignments within it will work. At
353 least one object format really uses this info. */
355 void
356 record_alignment (/* Segment to which alignment pertains. */
357 segT seg,
358 /* Alignment, as a power of 2 (e.g., 1 => 2-byte
359 boundary, 2 => 4-byte boundary, etc.) */
360 int align)
362 if (seg == absolute_section)
363 return;
365 if ((unsigned int) align > bfd_get_section_alignment (stdoutput, seg))
366 bfd_set_section_alignment (stdoutput, seg, align);
370 get_recorded_alignment (segT seg)
372 if (seg == absolute_section)
373 return 0;
375 return bfd_get_section_alignment (stdoutput, seg);
378 /* Reset the section indices after removing the gas created sections. */
380 static void
381 renumber_sections (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *countparg)
383 int *countp = (int *) countparg;
385 sec->index = *countp;
386 ++*countp;
389 static fragS *
390 chain_frchains_together_1 (segT section, struct frchain *frchp)
392 fragS dummy, *prev_frag = &dummy;
393 fixS fix_dummy, *prev_fix = &fix_dummy;
395 for (; frchp; frchp = frchp->frch_next)
397 prev_frag->fr_next = frchp->frch_root;
398 prev_frag = frchp->frch_last;
399 gas_assert (prev_frag->fr_type != 0);
400 if (frchp->fix_root != (fixS *) NULL)
402 if (seg_info (section)->fix_root == (fixS *) NULL)
403 seg_info (section)->fix_root = frchp->fix_root;
404 prev_fix->fx_next = frchp->fix_root;
405 seg_info (section)->fix_tail = frchp->fix_tail;
406 prev_fix = frchp->fix_tail;
409 gas_assert (prev_frag->fr_type != 0);
410 gas_assert (prev_frag != &dummy);
411 prev_frag->fr_next = 0;
412 return prev_frag;
415 static void
416 chain_frchains_together (bfd *abfd ATTRIBUTE_UNUSED,
417 segT section,
418 void *xxx ATTRIBUTE_UNUSED)
420 segment_info_type *info;
422 /* BFD may have introduced its own sections without using
423 subseg_new, so it is possible that seg_info is NULL. */
424 info = seg_info (section);
425 if (info != (segment_info_type *) NULL)
426 info->frchainP->frch_last
427 = chain_frchains_together_1 (section, info->frchainP);
429 /* Now that we've chained the frags together, we must add new fixups
430 to the segment, not to the frag chain. */
431 frags_chained = 1;
434 static void
435 cvt_frag_to_fill (segT sec ATTRIBUTE_UNUSED, fragS *fragP)
437 switch (fragP->fr_type)
439 case rs_align:
440 case rs_align_code:
441 case rs_align_test:
442 case rs_org:
443 case rs_space:
444 #ifdef HANDLE_ALIGN
445 HANDLE_ALIGN (fragP);
446 #endif
447 know (fragP->fr_next != NULL);
448 fragP->fr_offset = (fragP->fr_next->fr_address
449 - fragP->fr_address
450 - fragP->fr_fix) / fragP->fr_var;
451 if (fragP->fr_offset < 0)
453 as_bad_where (fragP->fr_file, fragP->fr_line,
454 _("attempt to .org/.space backwards? (%ld)"),
455 (long) fragP->fr_offset);
456 fragP->fr_offset = 0;
458 fragP->fr_type = rs_fill;
459 break;
461 case rs_fill:
462 break;
464 case rs_leb128:
466 valueT value = S_GET_VALUE (fragP->fr_symbol);
467 int size;
469 size = output_leb128 (fragP->fr_literal + fragP->fr_fix, value,
470 fragP->fr_subtype);
472 fragP->fr_fix += size;
473 fragP->fr_type = rs_fill;
474 fragP->fr_var = 0;
475 fragP->fr_offset = 0;
476 fragP->fr_symbol = NULL;
478 break;
480 case rs_cfa:
481 eh_frame_convert_frag (fragP);
482 break;
484 case rs_dwarf2dbg:
485 dwarf2dbg_convert_frag (fragP);
486 break;
488 case rs_machine_dependent:
489 md_convert_frag (stdoutput, sec, fragP);
491 gas_assert (fragP->fr_next == NULL
492 || ((offsetT) (fragP->fr_next->fr_address - fragP->fr_address)
493 == fragP->fr_fix));
495 /* After md_convert_frag, we make the frag into a ".space 0".
496 md_convert_frag() should set up any fixSs and constants
497 required. */
498 frag_wane (fragP);
499 break;
501 #ifndef WORKING_DOT_WORD
502 case rs_broken_word:
504 struct broken_word *lie;
506 if (fragP->fr_subtype)
508 fragP->fr_fix += md_short_jump_size;
509 for (lie = (struct broken_word *) (fragP->fr_symbol);
510 lie && lie->dispfrag == fragP;
511 lie = lie->next_broken_word)
512 if (lie->added == 1)
513 fragP->fr_fix += md_long_jump_size;
515 frag_wane (fragP);
517 break;
518 #endif
520 default:
521 BAD_CASE (fragP->fr_type);
522 break;
524 #ifdef md_frag_check
525 md_frag_check (fragP);
526 #endif
529 struct relax_seg_info
531 int pass;
532 int changed;
535 static void
536 relax_seg (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *xxx)
538 segment_info_type *seginfo = seg_info (sec);
539 struct relax_seg_info *info = (struct relax_seg_info *) xxx;
541 if (seginfo && seginfo->frchainP
542 && relax_segment (seginfo->frchainP->frch_root, sec, info->pass))
543 info->changed = 1;
546 static void
547 size_seg (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
549 flagword flags;
550 fragS *fragp;
551 segment_info_type *seginfo;
552 int x;
553 valueT size, newsize;
555 subseg_change (sec, 0);
557 seginfo = seg_info (sec);
558 if (seginfo && seginfo->frchainP)
560 for (fragp = seginfo->frchainP->frch_root; fragp; fragp = fragp->fr_next)
561 cvt_frag_to_fill (sec, fragp);
562 for (fragp = seginfo->frchainP->frch_root;
563 fragp->fr_next;
564 fragp = fragp->fr_next)
565 /* Walk to last elt. */
567 size = fragp->fr_address + fragp->fr_fix;
569 else
570 size = 0;
572 flags = bfd_get_section_flags (abfd, sec);
573 if (size == 0 && bfd_get_section_size (sec) != 0 &&
574 (flags & SEC_HAS_CONTENTS) != 0)
575 return;
577 if (size > 0 && ! seginfo->bss)
578 flags |= SEC_HAS_CONTENTS;
580 flags &= ~SEC_RELOC;
581 x = bfd_set_section_flags (abfd, sec, flags);
582 gas_assert (x);
584 newsize = md_section_align (sec, size);
585 x = bfd_set_section_size (abfd, sec, newsize);
586 gas_assert (x);
588 /* If the size had to be rounded up, add some padding in the last
589 non-empty frag. */
590 gas_assert (newsize >= size);
591 if (size != newsize)
593 fragS *last = seginfo->frchainP->frch_last;
594 fragp = seginfo->frchainP->frch_root;
595 while (fragp->fr_next != last)
596 fragp = fragp->fr_next;
597 last->fr_address = size;
598 if ((newsize - size) % fragp->fr_var == 0)
599 fragp->fr_offset += (newsize - size) / fragp->fr_var;
600 else
601 /* If we hit this abort, it's likely due to subsegs_finish not
602 providing sufficient alignment on the last frag, and the
603 machine dependent code using alignment frags with fr_var
604 greater than 1. */
605 abort ();
608 #ifdef tc_frob_section
609 tc_frob_section (sec);
610 #endif
611 #ifdef obj_frob_section
612 obj_frob_section (sec);
613 #endif
616 #ifdef DEBUG2
617 static void
618 dump_section_relocs (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, FILE *stream)
620 segment_info_type *seginfo = seg_info (sec);
621 fixS *fixp = seginfo->fix_root;
623 if (!fixp)
624 return;
626 fprintf (stream, "sec %s relocs:\n", sec->name);
627 while (fixp)
629 symbolS *s = fixp->fx_addsy;
631 fprintf (stream, " %08lx: type %d ", (unsigned long) fixp,
632 (int) fixp->fx_r_type);
633 if (s == NULL)
634 fprintf (stream, "no sym\n");
635 else
637 print_symbol_value_1 (stream, s);
638 fprintf (stream, "\n");
640 fixp = fixp->fx_next;
643 #else
644 #define dump_section_relocs(ABFD,SEC,STREAM) ((void) 0)
645 #endif
647 #ifndef EMIT_SECTION_SYMBOLS
648 #define EMIT_SECTION_SYMBOLS 1
649 #endif
651 /* Resolve U.A.OFFSET_SYM and U.A.SYM fields of RELOC_LIST entries,
652 and check for validity. Convert RELOC_LIST from using U.A fields
653 to U.B fields. */
654 static void
655 resolve_reloc_expr_symbols (void)
657 struct reloc_list *r;
659 for (r = reloc_list; r; r = r->next)
661 expressionS *symval;
662 symbolS *sym;
663 bfd_vma offset, addend;
664 asection *sec;
665 reloc_howto_type *howto;
667 resolve_symbol_value (r->u.a.offset_sym);
668 symval = symbol_get_value_expression (r->u.a.offset_sym);
670 offset = 0;
671 sym = NULL;
672 if (symval->X_op == O_constant)
673 sym = r->u.a.offset_sym;
674 else if (symval->X_op == O_symbol)
676 sym = symval->X_add_symbol;
677 offset = symval->X_add_number;
678 symval = symbol_get_value_expression (symval->X_add_symbol);
680 if (sym == NULL
681 || symval->X_op != O_constant
682 || (sec = S_GET_SEGMENT (sym)) == NULL
683 || !SEG_NORMAL (sec))
685 as_bad_where (r->file, r->line, _("invalid offset expression"));
686 sec = NULL;
688 else
689 offset += S_GET_VALUE (sym);
691 sym = NULL;
692 addend = r->u.a.addend;
693 if (r->u.a.sym != NULL)
695 resolve_symbol_value (r->u.a.sym);
696 symval = symbol_get_value_expression (r->u.a.sym);
697 if (symval->X_op == O_constant)
698 sym = r->u.a.sym;
699 else if (symval->X_op == O_symbol)
701 sym = symval->X_add_symbol;
702 addend += symval->X_add_number;
703 symval = symbol_get_value_expression (symval->X_add_symbol);
705 if (symval->X_op != O_constant)
707 as_bad_where (r->file, r->line, _("invalid reloc expression"));
708 sec = NULL;
710 else if (sym != NULL)
711 symbol_mark_used_in_reloc (sym);
713 if (sym == NULL)
715 if (abs_section_sym == NULL)
716 abs_section_sym = section_symbol (absolute_section);
717 sym = abs_section_sym;
720 howto = r->u.a.howto;
722 r->u.b.sec = sec;
723 r->u.b.s = symbol_get_bfdsym (sym);
724 r->u.b.r.sym_ptr_ptr = &r->u.b.s;
725 r->u.b.r.address = offset;
726 r->u.b.r.addend = addend;
727 r->u.b.r.howto = howto;
731 /* This pass over fixups decides whether symbols can be replaced with
732 section symbols. */
734 static void
735 adjust_reloc_syms (bfd *abfd ATTRIBUTE_UNUSED,
736 asection *sec,
737 void *xxx ATTRIBUTE_UNUSED)
739 segment_info_type *seginfo = seg_info (sec);
740 fixS *fixp;
742 if (seginfo == NULL)
743 return;
745 dump_section_relocs (abfd, sec, stderr);
747 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
748 if (fixp->fx_done)
749 /* Ignore it. */
751 else if (fixp->fx_addsy)
753 symbolS *sym;
754 asection *symsec;
756 #ifdef DEBUG5
757 fprintf (stderr, "\n\nadjusting fixup:\n");
758 print_fixup (fixp);
759 #endif
761 sym = fixp->fx_addsy;
763 /* All symbols should have already been resolved at this
764 point. It is possible to see unresolved expression
765 symbols, though, since they are not in the regular symbol
766 table. */
767 resolve_symbol_value (sym);
769 if (fixp->fx_subsy != NULL)
770 resolve_symbol_value (fixp->fx_subsy);
772 /* If this symbol is equated to an undefined or common symbol,
773 convert the fixup to being against that symbol. */
774 while (symbol_equated_reloc_p (sym)
775 || S_IS_WEAKREFR (sym))
777 symbolS *newsym = symbol_get_value_expression (sym)->X_add_symbol;
778 if (sym == newsym)
779 break;
780 fixp->fx_offset += symbol_get_value_expression (sym)->X_add_number;
781 fixp->fx_addsy = newsym;
782 sym = newsym;
785 if (symbol_mri_common_p (sym))
787 fixp->fx_offset += S_GET_VALUE (sym);
788 fixp->fx_addsy = symbol_get_value_expression (sym)->X_add_symbol;
789 continue;
792 /* If the symbol is undefined, common, weak, or global (ELF
793 shared libs), we can't replace it with the section symbol. */
794 if (S_FORCE_RELOC (fixp->fx_addsy, 1))
795 continue;
797 /* Is there some other (target cpu dependent) reason we can't adjust
798 this one? (E.g. relocations involving function addresses on
799 the PA. */
800 #ifdef tc_fix_adjustable
801 if (! tc_fix_adjustable (fixp))
802 continue;
803 #endif
805 /* Since we're reducing to section symbols, don't attempt to reduce
806 anything that's already using one. */
807 if (symbol_section_p (sym))
808 continue;
810 symsec = S_GET_SEGMENT (sym);
811 if (symsec == NULL)
812 abort ();
814 if (bfd_is_abs_section (symsec))
816 /* The fixup_segment routine normally will not use this
817 symbol in a relocation. */
818 continue;
821 /* Don't try to reduce relocs which refer to non-local symbols
822 in .linkonce sections. It can lead to confusion when a
823 debugging section refers to a .linkonce section. I hope
824 this will always be correct. */
825 if (symsec != sec && ! S_IS_LOCAL (sym))
827 if ((symsec->flags & SEC_LINK_ONCE) != 0
828 || (IS_ELF
829 /* The GNU toolchain uses an extension for ELF: a
830 section beginning with the magic string
831 .gnu.linkonce is a linkonce section. */
832 && strncmp (segment_name (symsec), ".gnu.linkonce",
833 sizeof ".gnu.linkonce" - 1) == 0))
834 continue;
837 /* Never adjust a reloc against local symbol in a merge section
838 with non-zero addend. */
839 if ((symsec->flags & SEC_MERGE) != 0
840 && (fixp->fx_offset != 0 || fixp->fx_subsy != NULL))
841 continue;
843 /* Never adjust a reloc against TLS local symbol. */
844 if ((symsec->flags & SEC_THREAD_LOCAL) != 0)
845 continue;
847 /* We refetch the segment when calling section_symbol, rather
848 than using symsec, because S_GET_VALUE may wind up changing
849 the section when it calls resolve_symbol_value. */
850 fixp->fx_offset += S_GET_VALUE (sym);
851 fixp->fx_addsy = section_symbol (S_GET_SEGMENT (sym));
852 #ifdef DEBUG5
853 fprintf (stderr, "\nadjusted fixup:\n");
854 print_fixup (fixp);
855 #endif
858 dump_section_relocs (abfd, sec, stderr);
861 /* fixup_segment()
863 Go through all the fixS's in a segment and see which ones can be
864 handled now. (These consist of fixS where we have since discovered
865 the value of a symbol, or the address of the frag involved.)
866 For each one, call md_apply_fix to put the fix into the frag data.
868 Result is a count of how many relocation structs will be needed to
869 handle the remaining fixS's that we couldn't completely handle here.
870 These will be output later by emit_relocations(). */
872 static long
873 fixup_segment (fixS *fixP, segT this_segment)
875 long seg_reloc_count = 0;
876 valueT add_number;
877 fragS *fragP;
878 segT add_symbol_segment = absolute_section;
880 if (fixP != NULL && abs_section_sym == NULL)
881 abs_section_sym = section_symbol (absolute_section);
883 /* If the linker is doing the relaxing, we must not do any fixups.
885 Well, strictly speaking that's not true -- we could do any that
886 are PC-relative and don't cross regions that could change size.
887 And for the i960 we might be able to turn callx/callj into bal
888 anyways in cases where we know the maximum displacement. */
889 if (linkrelax && TC_LINKRELAX_FIXUP (this_segment))
891 for (; fixP; fixP = fixP->fx_next)
892 if (!fixP->fx_done)
894 if (fixP->fx_addsy == NULL)
896 /* There was no symbol required by this relocation.
897 However, BFD doesn't really handle relocations
898 without symbols well. So fake up a local symbol in
899 the absolute section. */
900 fixP->fx_addsy = abs_section_sym;
902 symbol_mark_used_in_reloc (fixP->fx_addsy);
903 if (fixP->fx_subsy != NULL)
904 symbol_mark_used_in_reloc (fixP->fx_subsy);
905 seg_reloc_count++;
907 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
908 return seg_reloc_count;
911 for (; fixP; fixP = fixP->fx_next)
913 #ifdef DEBUG5
914 fprintf (stderr, "\nprocessing fixup:\n");
915 print_fixup (fixP);
916 #endif
918 fragP = fixP->fx_frag;
919 know (fragP);
920 #ifdef TC_VALIDATE_FIX
921 TC_VALIDATE_FIX (fixP, this_segment, skip);
922 #endif
923 add_number = fixP->fx_offset;
925 if (fixP->fx_addsy != NULL)
926 add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy);
928 if (fixP->fx_subsy != NULL)
930 segT sub_symbol_segment;
931 resolve_symbol_value (fixP->fx_subsy);
932 sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy);
933 if (fixP->fx_addsy != NULL
934 && sub_symbol_segment == add_symbol_segment
935 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
936 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
937 && !TC_FORCE_RELOCATION_SUB_SAME (fixP, add_symbol_segment))
939 add_number += S_GET_VALUE (fixP->fx_addsy);
940 add_number -= S_GET_VALUE (fixP->fx_subsy);
941 fixP->fx_offset = add_number;
942 fixP->fx_addsy = NULL;
943 fixP->fx_subsy = NULL;
944 #ifdef TC_M68K
945 /* See the comment below about 68k weirdness. */
946 fixP->fx_pcrel = 0;
947 #endif
949 else if (sub_symbol_segment == absolute_section
950 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
951 && !TC_FORCE_RELOCATION_SUB_ABS (fixP, add_symbol_segment))
953 add_number -= S_GET_VALUE (fixP->fx_subsy);
954 fixP->fx_offset = add_number;
955 fixP->fx_subsy = NULL;
957 else if (sub_symbol_segment == this_segment
958 && !S_FORCE_RELOC (fixP->fx_subsy, 0)
959 && !TC_FORCE_RELOCATION_SUB_LOCAL (fixP, add_symbol_segment))
961 add_number -= S_GET_VALUE (fixP->fx_subsy);
962 fixP->fx_offset = (add_number + fixP->fx_dot_value
963 + fixP->fx_frag->fr_address);
965 /* Make it pc-relative. If the back-end code has not
966 selected a pc-relative reloc, cancel the adjustment
967 we do later on all pc-relative relocs. */
968 if (0
969 #ifdef TC_M68K
970 /* Do this for m68k even if it's already described
971 as pc-relative. On the m68k, an operand of
972 "pc@(foo-.-2)" should address "foo" in a
973 pc-relative mode. */
974 || 1
975 #endif
976 || !fixP->fx_pcrel)
977 add_number += MD_PCREL_FROM_SECTION (fixP, this_segment);
978 fixP->fx_subsy = NULL;
979 fixP->fx_pcrel = 1;
981 else if (!TC_VALIDATE_FIX_SUB (fixP, add_symbol_segment))
983 if (!md_register_arithmetic
984 && (add_symbol_segment == reg_section
985 || sub_symbol_segment == reg_section))
986 as_bad_where (fixP->fx_file, fixP->fx_line,
987 _("register value used as expression"));
988 else
989 as_bad_where (fixP->fx_file, fixP->fx_line,
990 _("can't resolve `%s' {%s section} - `%s' {%s section}"),
991 fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
992 segment_name (add_symbol_segment),
993 S_GET_NAME (fixP->fx_subsy),
994 segment_name (sub_symbol_segment));
998 if (fixP->fx_addsy)
1000 if (add_symbol_segment == this_segment
1001 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1002 && !TC_FORCE_RELOCATION_LOCAL (fixP))
1004 /* This fixup was made when the symbol's segment was
1005 SEG_UNKNOWN, but it is now in the local segment.
1006 So we know how to do the address without relocation. */
1007 add_number += S_GET_VALUE (fixP->fx_addsy);
1008 fixP->fx_offset = add_number;
1009 if (fixP->fx_pcrel)
1010 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1011 fixP->fx_addsy = NULL;
1012 fixP->fx_pcrel = 0;
1014 else if (add_symbol_segment == absolute_section
1015 && !S_FORCE_RELOC (fixP->fx_addsy, 0)
1016 && !TC_FORCE_RELOCATION_ABS (fixP))
1018 add_number += S_GET_VALUE (fixP->fx_addsy);
1019 fixP->fx_offset = add_number;
1020 fixP->fx_addsy = NULL;
1022 else if (add_symbol_segment != undefined_section
1023 && ! bfd_is_com_section (add_symbol_segment)
1024 && MD_APPLY_SYM_VALUE (fixP))
1025 add_number += S_GET_VALUE (fixP->fx_addsy);
1028 if (fixP->fx_pcrel)
1030 add_number -= MD_PCREL_FROM_SECTION (fixP, this_segment);
1031 if (!fixP->fx_done && fixP->fx_addsy == NULL)
1033 /* There was no symbol required by this relocation.
1034 However, BFD doesn't really handle relocations
1035 without symbols well. So fake up a local symbol in
1036 the absolute section. */
1037 fixP->fx_addsy = abs_section_sym;
1041 if (!fixP->fx_done)
1042 md_apply_fix (fixP, &add_number, this_segment);
1044 if (!fixP->fx_done)
1046 ++seg_reloc_count;
1047 if (fixP->fx_addsy == NULL)
1048 fixP->fx_addsy = abs_section_sym;
1049 symbol_mark_used_in_reloc (fixP->fx_addsy);
1050 if (fixP->fx_subsy != NULL)
1051 symbol_mark_used_in_reloc (fixP->fx_subsy);
1054 if (!fixP->fx_bit_fixP && !fixP->fx_no_overflow && fixP->fx_size != 0)
1056 if (fixP->fx_size < sizeof (valueT))
1058 valueT mask;
1060 mask = 0;
1061 mask--; /* Set all bits to one. */
1062 mask <<= fixP->fx_size * 8 - (fixP->fx_signed ? 1 : 0);
1063 if ((add_number & mask) != 0 && (add_number & mask) != mask)
1065 char buf[50], buf2[50];
1066 sprint_value (buf, fragP->fr_address + fixP->fx_where);
1067 if (add_number > 1000)
1068 sprint_value (buf2, add_number);
1069 else
1070 sprintf (buf2, "%ld", (long) add_number);
1071 as_bad_where (fixP->fx_file, fixP->fx_line,
1072 _("value of %s too large for field of %d bytes at %s"),
1073 buf2, fixP->fx_size, buf);
1074 } /* Generic error checking. */
1076 #ifdef WARN_SIGNED_OVERFLOW_WORD
1077 /* Warn if a .word value is too large when treated as a signed
1078 number. We already know it is not too negative. This is to
1079 catch over-large switches generated by gcc on the 68k. */
1080 if (!flag_signed_overflow_ok
1081 && fixP->fx_size == 2
1082 && add_number > 0x7fff)
1083 as_bad_where (fixP->fx_file, fixP->fx_line,
1084 _("signed .word overflow; switch may be too large; %ld at 0x%lx"),
1085 (long) add_number,
1086 (long) (fragP->fr_address + fixP->fx_where));
1087 #endif
1088 } /* Not a bit fix. */
1090 #ifdef TC_VALIDATE_FIX
1091 skip: ATTRIBUTE_UNUSED_LABEL
1093 #endif
1094 #ifdef DEBUG5
1095 fprintf (stderr, "result:\n");
1096 print_fixup (fixP);
1097 #endif
1098 } /* For each fixS in this segment. */
1100 TC_ADJUST_RELOC_COUNT (fixP, seg_reloc_count);
1101 return seg_reloc_count;
1104 static void
1105 fix_segment (bfd *abfd ATTRIBUTE_UNUSED,
1106 asection *sec,
1107 void *xxx ATTRIBUTE_UNUSED)
1109 segment_info_type *seginfo = seg_info (sec);
1111 fixup_segment (seginfo->fix_root, sec);
1114 static void
1115 install_reloc (asection *sec, arelent *reloc, fragS *fragp,
1116 char *file, unsigned int line)
1118 char *err;
1119 bfd_reloc_status_type s;
1120 asymbol *sym;
1122 if (reloc->sym_ptr_ptr != NULL
1123 && (sym = *reloc->sym_ptr_ptr) != NULL
1124 && (sym->flags & BSF_KEEP) == 0
1125 && ((sym->flags & BSF_SECTION_SYM) == 0
1126 || (EMIT_SECTION_SYMBOLS
1127 && !bfd_is_abs_section (sym->section))))
1128 as_bad_where (file, line, _("redefined symbol cannot be used on reloc"));
1130 s = bfd_install_relocation (stdoutput, reloc,
1131 fragp->fr_literal, fragp->fr_address,
1132 sec, &err);
1133 switch (s)
1135 case bfd_reloc_ok:
1136 break;
1137 case bfd_reloc_overflow:
1138 as_bad_where (file, line, _("relocation overflow"));
1139 break;
1140 case bfd_reloc_outofrange:
1141 as_bad_where (file, line, _("relocation out of range"));
1142 break;
1143 default:
1144 as_fatal (_("%s:%u: bad return from bfd_install_relocation: %x"),
1145 file, line, s);
1149 static void
1150 write_relocs (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1152 segment_info_type *seginfo = seg_info (sec);
1153 unsigned int i;
1154 unsigned int n;
1155 struct reloc_list *my_reloc_list, **rp, *r;
1156 arelent **relocs;
1157 fixS *fixp;
1159 /* If seginfo is NULL, we did not create this section; don't do
1160 anything with it. */
1161 if (seginfo == NULL)
1162 return;
1164 n = 0;
1165 for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
1166 if (!fixp->fx_done)
1167 n++;
1169 #ifdef RELOC_EXPANSION_POSSIBLE
1170 n *= MAX_RELOC_EXPANSION;
1171 #endif
1173 /* Extract relocs for this section from reloc_list. */
1174 rp = &reloc_list;
1175 my_reloc_list = NULL;
1176 while ((r = *rp) != NULL)
1178 if (r->u.b.sec == sec)
1180 *rp = r->next;
1181 r->next = my_reloc_list;
1182 my_reloc_list = r;
1183 n++;
1185 else
1186 rp = &r->next;
1189 relocs = (arelent **) xcalloc (n, sizeof (arelent *));
1191 i = 0;
1192 for (fixp = seginfo->fix_root; fixp != (fixS *) NULL; fixp = fixp->fx_next)
1194 int j;
1195 int fx_size, slack;
1196 offsetT loc;
1198 if (fixp->fx_done)
1199 continue;
1201 fx_size = fixp->fx_size;
1202 slack = TC_FX_SIZE_SLACK (fixp);
1203 if (slack > 0)
1204 fx_size = fx_size > slack ? fx_size - slack : 0;
1205 loc = fixp->fx_where + fx_size;
1206 if (slack >= 0 && loc > fixp->fx_frag->fr_fix)
1207 as_bad_where (fixp->fx_file, fixp->fx_line,
1208 _("internal error: fixup not contained within frag"));
1210 #ifndef RELOC_EXPANSION_POSSIBLE
1212 arelent *reloc = tc_gen_reloc (sec, fixp);
1214 if (!reloc)
1215 continue;
1216 relocs[i++] = reloc;
1217 j = 1;
1219 #else
1221 arelent **reloc = tc_gen_reloc (sec, fixp);
1223 for (j = 0; reloc[j]; j++)
1224 relocs[i++] = reloc[j];
1226 #endif
1228 for ( ; j != 0; --j)
1229 install_reloc (sec, relocs[i - j], fixp->fx_frag,
1230 fixp->fx_file, fixp->fx_line);
1232 n = i;
1234 #ifdef DEBUG4
1236 unsigned int i, j, nsyms;
1237 asymbol **sympp;
1238 sympp = bfd_get_outsymbols (stdoutput);
1239 nsyms = bfd_get_symcount (stdoutput);
1240 for (i = 0; i < n; i++)
1241 if (((*relocs[i]->sym_ptr_ptr)->flags & BSF_SECTION_SYM) == 0)
1243 for (j = 0; j < nsyms; j++)
1244 if (sympp[j] == *relocs[i]->sym_ptr_ptr)
1245 break;
1246 if (j == nsyms)
1247 abort ();
1250 #endif
1252 for (r = my_reloc_list; r != NULL; r = r->next)
1254 fragS *f;
1255 for (f = seginfo->frchainP->frch_root; f; f = f->fr_next)
1256 if (f->fr_address <= r->u.b.r.address
1257 && r->u.b.r.address < f->fr_address + f->fr_fix)
1258 break;
1259 if (f == NULL)
1260 as_bad_where (r->file, r->line,
1261 _("reloc not within (fixed part of) section"));
1262 else
1264 relocs[n++] = &r->u.b.r;
1265 install_reloc (sec, &r->u.b.r, f, r->file, r->line);
1269 if (n)
1271 flagword flags = bfd_get_section_flags (abfd, sec);
1272 flags |= SEC_RELOC;
1273 bfd_set_section_flags (abfd, sec, flags);
1274 bfd_set_reloc (stdoutput, sec, relocs, n);
1277 #ifdef SET_SECTION_RELOCS
1278 SET_SECTION_RELOCS (sec, relocs, n);
1279 #endif
1281 #ifdef DEBUG3
1283 unsigned int i;
1284 arelent *r;
1285 asymbol *s;
1286 fprintf (stderr, "relocs for sec %s\n", sec->name);
1287 for (i = 0; i < n; i++)
1289 r = relocs[i];
1290 s = *r->sym_ptr_ptr;
1291 fprintf (stderr, " reloc %2d @%p off %4lx : sym %-10s addend %lx\n",
1292 i, r, (unsigned long)r->address, s->name, (unsigned long)r->addend);
1295 #endif
1298 static int
1299 compress_frag (struct z_stream_s *strm, const char *contents, int in_size,
1300 fragS **last_newf, struct obstack *ob)
1302 int out_size;
1303 int total_out_size = 0;
1304 fragS *f = *last_newf;
1305 char *next_out;
1306 int avail_out;
1308 /* Call the compression routine repeatedly until it has finished
1309 processing the frag. */
1310 while (in_size > 0)
1312 /* Reserve all the space available in the current chunk.
1313 If none is available, start a new frag. */
1314 avail_out = obstack_room (ob);
1315 if (avail_out <= 0)
1317 obstack_finish (ob);
1318 f = frag_alloc (ob);
1319 f->fr_type = rs_fill;
1320 (*last_newf)->fr_next = f;
1321 *last_newf = f;
1322 avail_out = obstack_room (ob);
1324 if (avail_out <= 0)
1325 as_fatal (_("can't extend frag"));
1326 next_out = obstack_next_free (ob);
1327 obstack_blank_fast (ob, avail_out);
1328 out_size = compress_data (strm, &contents, &in_size,
1329 &next_out, &avail_out);
1330 if (out_size < 0)
1331 return -1;
1333 f->fr_fix += out_size;
1334 total_out_size += out_size;
1336 /* Return unused space. */
1337 if (avail_out > 0)
1338 obstack_blank_fast (ob, -avail_out);
1341 return total_out_size;
1344 static void
1345 compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
1347 segment_info_type *seginfo = seg_info (sec);
1348 fragS *f;
1349 fragS *first_newf;
1350 fragS *last_newf;
1351 struct obstack *ob = &seginfo->frchainP->frch_obstack;
1352 bfd_size_type uncompressed_size = (bfd_size_type) sec->size;
1353 bfd_size_type compressed_size;
1354 const char *section_name;
1355 char *compressed_name;
1356 char *header;
1357 struct z_stream_s *strm;
1358 int x;
1359 flagword flags = bfd_get_section_flags (abfd, sec);
1361 if (seginfo == NULL
1362 || sec->size < 32
1363 || (flags & (SEC_ALLOC | SEC_HAS_CONTENTS)) == SEC_ALLOC)
1364 return;
1366 section_name = bfd_get_section_name (stdoutput, sec);
1367 if (strncmp (section_name, ".debug_", 7) != 0)
1368 return;
1370 strm = compress_init ();
1371 if (strm == NULL)
1372 return;
1374 /* Create a new frag to contain the "ZLIB" header. */
1375 first_newf = frag_alloc (ob);
1376 if (obstack_room (ob) < 12)
1377 first_newf = frag_alloc (ob);
1378 if (obstack_room (ob) < 12)
1379 as_fatal (_("can't extend frag %u chars"), 12);
1380 last_newf = first_newf;
1381 obstack_blank_fast (ob, 12);
1382 last_newf->fr_type = rs_fill;
1383 last_newf->fr_fix = 12;
1384 header = last_newf->fr_literal;
1385 memcpy (header, "ZLIB", 4);
1386 header[11] = uncompressed_size; uncompressed_size >>= 8;
1387 header[10] = uncompressed_size; uncompressed_size >>= 8;
1388 header[9] = uncompressed_size; uncompressed_size >>= 8;
1389 header[8] = uncompressed_size; uncompressed_size >>= 8;
1390 header[7] = uncompressed_size; uncompressed_size >>= 8;
1391 header[6] = uncompressed_size; uncompressed_size >>= 8;
1392 header[5] = uncompressed_size; uncompressed_size >>= 8;
1393 header[4] = uncompressed_size;
1394 compressed_size = 12;
1396 /* Stream the frags through the compression engine, adding new frags
1397 as necessary to accomodate the compressed output. */
1398 for (f = seginfo->frchainP->frch_root;
1400 f = f->fr_next)
1402 offsetT fill_size;
1403 char *fill_literal;
1404 offsetT count;
1405 int out_size;
1407 gas_assert (f->fr_type == rs_fill);
1408 if (f->fr_fix)
1410 out_size = compress_frag (strm, f->fr_literal, f->fr_fix,
1411 &last_newf, ob);
1412 if (out_size < 0)
1413 return;
1414 compressed_size += out_size;
1416 fill_literal = f->fr_literal + f->fr_fix;
1417 fill_size = f->fr_var;
1418 count = f->fr_offset;
1419 gas_assert (count >= 0);
1420 if (fill_size && count)
1422 while (count--)
1424 out_size = compress_frag (strm, fill_literal, (int) fill_size,
1425 &last_newf, ob);
1426 if (out_size < 0)
1427 return;
1428 compressed_size += out_size;
1433 /* Flush the compression state. */
1434 for (;;)
1436 int avail_out;
1437 char *next_out;
1438 int out_size;
1440 /* Reserve all the space available in the current chunk.
1441 If none is available, start a new frag. */
1442 avail_out = obstack_room (ob);
1443 if (avail_out <= 0)
1445 fragS *newf;
1447 obstack_finish (ob);
1448 newf = frag_alloc (ob);
1449 newf->fr_type = rs_fill;
1450 last_newf->fr_next = newf;
1451 last_newf = newf;
1452 avail_out = obstack_room (ob);
1454 if (avail_out <= 0)
1455 as_fatal (_("can't extend frag"));
1456 next_out = obstack_next_free (ob);
1457 obstack_blank_fast (ob, avail_out);
1458 x = compress_finish (strm, &next_out, &avail_out, &out_size);
1459 if (x < 0)
1460 return;
1462 last_newf->fr_fix += out_size;
1463 compressed_size += out_size;
1465 /* Return unused space. */
1466 if (avail_out > 0)
1467 obstack_blank_fast (ob, -avail_out);
1469 if (x == 0)
1470 break;
1473 /* Replace the uncompressed frag list with the compressed frag list. */
1474 seginfo->frchainP->frch_root = first_newf;
1475 seginfo->frchainP->frch_last = last_newf;
1477 /* Update the section size and its name. */
1478 x = bfd_set_section_size (abfd, sec, compressed_size);
1479 gas_assert (x);
1480 compressed_name = (char *) xmalloc (strlen (section_name) + 2);
1481 compressed_name[0] = '.';
1482 compressed_name[1] = 'z';
1483 strcpy (compressed_name + 2, section_name + 1);
1484 bfd_section_name (stdoutput, sec) = compressed_name;
1487 static void
1488 write_contents (bfd *abfd ATTRIBUTE_UNUSED,
1489 asection *sec,
1490 void *xxx ATTRIBUTE_UNUSED)
1492 segment_info_type *seginfo = seg_info (sec);
1493 addressT offset = 0;
1494 fragS *f;
1496 /* Write out the frags. */
1497 if (seginfo == NULL
1498 || !(bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS))
1499 return;
1501 for (f = seginfo->frchainP->frch_root;
1503 f = f->fr_next)
1505 int x;
1506 addressT fill_size;
1507 char *fill_literal;
1508 offsetT count;
1510 gas_assert (f->fr_type == rs_fill);
1511 if (f->fr_fix)
1513 x = bfd_set_section_contents (stdoutput, sec,
1514 f->fr_literal, (file_ptr) offset,
1515 (bfd_size_type) f->fr_fix);
1516 if (!x)
1517 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1518 bfd_errmsg (bfd_get_error ()));
1519 offset += f->fr_fix;
1521 fill_literal = f->fr_literal + f->fr_fix;
1522 fill_size = f->fr_var;
1523 count = f->fr_offset;
1524 gas_assert (count >= 0);
1525 if (fill_size && count)
1527 char buf[256];
1528 if (fill_size > sizeof (buf))
1530 /* Do it the old way. Can this ever happen? */
1531 while (count--)
1533 x = bfd_set_section_contents (stdoutput, sec,
1534 fill_literal,
1535 (file_ptr) offset,
1536 (bfd_size_type) fill_size);
1537 if (!x)
1538 as_fatal (_("can't write %s: %s"), stdoutput->filename,
1539 bfd_errmsg (bfd_get_error ()));
1540 offset += fill_size;
1543 else
1545 /* Build a buffer full of fill objects and output it as
1546 often as necessary. This saves on the overhead of
1547 potentially lots of bfd_set_section_contents calls. */
1548 int n_per_buf, i;
1549 if (fill_size == 1)
1551 n_per_buf = sizeof (buf);
1552 memset (buf, *fill_literal, n_per_buf);
1554 else
1556 char *bufp;
1557 n_per_buf = sizeof (buf) / fill_size;
1558 for (i = n_per_buf, bufp = buf; i; i--, bufp += fill_size)
1559 memcpy (bufp, fill_literal, fill_size);
1561 for (; count > 0; count -= n_per_buf)
1563 n_per_buf = n_per_buf > count ? count : n_per_buf;
1564 x = bfd_set_section_contents
1565 (stdoutput, sec, buf, (file_ptr) offset,
1566 (bfd_size_type) n_per_buf * fill_size);
1567 if (!x)
1568 as_fatal (_("cannot write to output file"));
1569 offset += n_per_buf * fill_size;
1576 static void
1577 merge_data_into_text (void)
1579 seg_info (text_section)->frchainP->frch_last->fr_next =
1580 seg_info (data_section)->frchainP->frch_root;
1581 seg_info (text_section)->frchainP->frch_last =
1582 seg_info (data_section)->frchainP->frch_last;
1583 seg_info (data_section)->frchainP = 0;
1586 static void
1587 set_symtab (void)
1589 int nsyms;
1590 asymbol **asympp;
1591 symbolS *symp;
1592 bfd_boolean result;
1594 /* Count symbols. We can't rely on a count made by the loop in
1595 write_object_file, because *_frob_file may add a new symbol or
1596 two. */
1597 nsyms = 0;
1598 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1599 nsyms++;
1601 if (nsyms)
1603 int i;
1604 bfd_size_type amt = (bfd_size_type) nsyms * sizeof (asymbol *);
1606 asympp = (asymbol **) bfd_alloc (stdoutput, amt);
1607 symp = symbol_rootP;
1608 for (i = 0; i < nsyms; i++, symp = symbol_next (symp))
1610 asympp[i] = symbol_get_bfdsym (symp);
1611 if (asympp[i]->flags != BSF_SECTION_SYM
1612 || !(bfd_is_const_section (asympp[i]->section)
1613 && asympp[i]->section->symbol == asympp[i]))
1614 asympp[i]->flags |= BSF_KEEP;
1615 symbol_mark_written (symp);
1618 else
1619 asympp = 0;
1620 result = bfd_set_symtab (stdoutput, asympp, nsyms);
1621 gas_assert (result);
1622 symbol_table_frozen = 1;
1625 /* Finish the subsegments. After every sub-segment, we fake an
1626 ".align ...". This conforms to BSD4.2 brane-damage. We then fake
1627 ".fill 0" because that is the kind of frag that requires least
1628 thought. ".align" frags like to have a following frag since that
1629 makes calculating their intended length trivial. */
1631 #ifndef SUB_SEGMENT_ALIGN
1632 #ifdef HANDLE_ALIGN
1633 /* The last subsegment gets an alignment corresponding to the alignment
1634 of the section. This allows proper nop-filling at the end of
1635 code-bearing sections. */
1636 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
1637 (!(FRCHAIN)->frch_next ? get_recorded_alignment (SEG) : 0)
1638 #else
1639 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) 0
1640 #endif
1641 #endif
1643 void
1644 subsegs_finish (void)
1646 struct frchain *frchainP;
1647 asection *s;
1649 for (s = stdoutput->sections; s; s = s->next)
1651 segment_info_type *seginfo = seg_info (s);
1652 if (!seginfo)
1653 continue;
1655 for (frchainP = seginfo->frchainP;
1656 frchainP != NULL;
1657 frchainP = frchainP->frch_next)
1659 int alignment = 0;
1661 subseg_set (s, frchainP->frch_subseg);
1663 /* This now gets called even if we had errors. In that case,
1664 any alignment is meaningless, and, moreover, will look weird
1665 if we are generating a listing. */
1666 if (!had_errors ())
1668 alignment = SUB_SEGMENT_ALIGN (now_seg, frchainP);
1669 if ((bfd_get_section_flags (now_seg->owner, now_seg) & SEC_MERGE)
1670 && now_seg->entsize)
1672 unsigned int entsize = now_seg->entsize;
1673 int entalign = 0;
1675 while ((entsize & 1) == 0)
1677 ++entalign;
1678 entsize >>= 1;
1680 if (entalign > alignment)
1681 alignment = entalign;
1685 if (subseg_text_p (now_seg))
1686 frag_align_code (alignment, 0);
1687 else
1688 frag_align (alignment, 0, 0);
1690 /* frag_align will have left a new frag.
1691 Use this last frag for an empty ".fill".
1693 For this segment ...
1694 Create a last frag. Do not leave a "being filled in frag". */
1695 frag_wane (frag_now);
1696 frag_now->fr_fix = 0;
1697 know (frag_now->fr_next == NULL);
1702 /* Write the object file. */
1704 void
1705 write_object_file (void)
1707 struct relax_seg_info rsi;
1708 #ifndef WORKING_DOT_WORD
1709 fragS *fragP; /* Track along all frags. */
1710 #endif
1712 /* Do we really want to write it? */
1714 int n_warns, n_errs;
1715 n_warns = had_warnings ();
1716 n_errs = had_errors ();
1717 /* The -Z flag indicates that an object file should be generated,
1718 regardless of warnings and errors. */
1719 if (flag_always_generate_output)
1721 if (n_warns || n_errs)
1722 as_warn (_("%d error%s, %d warning%s, generating bad object file"),
1723 n_errs, n_errs == 1 ? "" : "s",
1724 n_warns, n_warns == 1 ? "" : "s");
1726 else
1728 if (n_errs)
1729 as_fatal (_("%d error%s, %d warning%s, no object file generated"),
1730 n_errs, n_errs == 1 ? "" : "s",
1731 n_warns, n_warns == 1 ? "" : "s");
1735 #ifdef OBJ_VMS
1736 /* Under VMS we try to be compatible with VAX-11 "C". Thus, we call
1737 a routine to check for the definition of the procedure "_main",
1738 and if so -- fix it up so that it can be program entry point. */
1739 vms_check_for_main ();
1740 #endif /* OBJ_VMS */
1742 /* From now on, we don't care about sub-segments. Build one frag chain
1743 for each segment. Linked thru fr_next. */
1745 /* Remove the sections created by gas for its own purposes. */
1747 int i;
1749 bfd_section_list_remove (stdoutput, reg_section);
1750 bfd_section_list_remove (stdoutput, expr_section);
1751 stdoutput->section_count -= 2;
1752 i = 0;
1753 bfd_map_over_sections (stdoutput, renumber_sections, &i);
1756 bfd_map_over_sections (stdoutput, chain_frchains_together, (char *) 0);
1758 /* We have two segments. If user gave -R flag, then we must put the
1759 data frags into the text segment. Do this before relaxing so
1760 we know to take advantage of -R and make shorter addresses. */
1761 if (flag_readonly_data_in_text)
1763 merge_data_into_text ();
1766 rsi.pass = 0;
1767 while (1)
1769 #ifndef WORKING_DOT_WORD
1770 /* We need to reset the markers in the broken word list and
1771 associated frags between calls to relax_segment (via
1772 relax_seg). Since the broken word list is global, we do it
1773 once per round, rather than locally in relax_segment for each
1774 segment. */
1775 struct broken_word *brokp;
1777 for (brokp = broken_words;
1778 brokp != (struct broken_word *) NULL;
1779 brokp = brokp->next_broken_word)
1781 brokp->added = 0;
1783 if (brokp->dispfrag != (fragS *) NULL
1784 && brokp->dispfrag->fr_type == rs_broken_word)
1785 brokp->dispfrag->fr_subtype = 0;
1787 #endif
1789 rsi.changed = 0;
1790 bfd_map_over_sections (stdoutput, relax_seg, &rsi);
1791 rsi.pass++;
1792 if (!rsi.changed)
1793 break;
1796 /* Note - Most ports will use the default value of
1797 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG, which 1. This will force
1798 local symbols to be resolved, removing their frag information.
1799 Some ports however, will not have finished relaxing all of
1800 their frags and will still need the local symbol frag
1801 information. These ports can set
1802 TC_FINALIZE_SYMS_BEFORE_SIZE_SEG to 0. */
1803 finalize_syms = TC_FINALIZE_SYMS_BEFORE_SIZE_SEG;
1805 bfd_map_over_sections (stdoutput, size_seg, (char *) 0);
1807 /* Relaxation has completed. Freeze all syms. */
1808 finalize_syms = 1;
1810 #ifdef md_post_relax_hook
1811 md_post_relax_hook;
1812 #endif
1814 #ifndef WORKING_DOT_WORD
1816 struct broken_word *lie;
1817 struct broken_word **prevP;
1819 prevP = &broken_words;
1820 for (lie = broken_words; lie; lie = lie->next_broken_word)
1821 if (!lie->added)
1823 expressionS exp;
1825 subseg_change (lie->seg, lie->subseg);
1826 exp.X_op = O_subtract;
1827 exp.X_add_symbol = lie->add;
1828 exp.X_op_symbol = lie->sub;
1829 exp.X_add_number = lie->addnum;
1830 #ifdef TC_CONS_FIX_NEW
1831 TC_CONS_FIX_NEW (lie->frag,
1832 lie->word_goes_here - lie->frag->fr_literal,
1833 2, &exp);
1834 #else
1835 fix_new_exp (lie->frag,
1836 lie->word_goes_here - lie->frag->fr_literal,
1837 2, &exp, 0, BFD_RELOC_16);
1838 #endif
1839 *prevP = lie->next_broken_word;
1841 else
1842 prevP = &(lie->next_broken_word);
1844 for (lie = broken_words; lie;)
1846 struct broken_word *untruth;
1847 char *table_ptr;
1848 addressT table_addr;
1849 addressT from_addr, to_addr;
1850 int n, m;
1852 subseg_change (lie->seg, lie->subseg);
1853 fragP = lie->dispfrag;
1855 /* Find out how many broken_words go here. */
1856 n = 0;
1857 for (untruth = lie;
1858 untruth && untruth->dispfrag == fragP;
1859 untruth = untruth->next_broken_word)
1860 if (untruth->added == 1)
1861 n++;
1863 table_ptr = lie->dispfrag->fr_opcode;
1864 table_addr = (lie->dispfrag->fr_address
1865 + (table_ptr - lie->dispfrag->fr_literal));
1866 /* Create the jump around the long jumps. This is a short
1867 jump from table_ptr+0 to table_ptr+n*long_jump_size. */
1868 from_addr = table_addr;
1869 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
1870 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1871 lie->add);
1872 table_ptr += md_short_jump_size;
1873 table_addr += md_short_jump_size;
1875 for (m = 0;
1876 lie && lie->dispfrag == fragP;
1877 m++, lie = lie->next_broken_word)
1879 if (lie->added == 2)
1880 continue;
1881 /* Patch the jump table. */
1882 for (untruth = (struct broken_word *) (fragP->fr_symbol);
1883 untruth && untruth->dispfrag == fragP;
1884 untruth = untruth->next_broken_word)
1886 if (untruth->use_jump == lie)
1888 /* This is the offset from ??? to table_ptr+0.
1889 The target is the same for all users of this
1890 md_long_jump, but the "sub" bases (and hence the
1891 offsets) may be different. */
1892 addressT to_word = table_addr - S_GET_VALUE (untruth->sub);
1893 #ifdef TC_CHECK_ADJUSTED_BROKEN_DOT_WORD
1894 TC_CHECK_ADJUSTED_BROKEN_DOT_WORD (to_word, untruth);
1895 #endif
1896 md_number_to_chars (untruth->word_goes_here, to_word, 2);
1900 /* Install the long jump. */
1901 /* This is a long jump from table_ptr+0 to the final target. */
1902 from_addr = table_addr;
1903 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
1904 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag,
1905 lie->add);
1906 table_ptr += md_long_jump_size;
1907 table_addr += md_long_jump_size;
1911 #endif /* not WORKING_DOT_WORD */
1913 /* Resolve symbol values. This needs to be done before processing
1914 the relocations. */
1915 if (symbol_rootP)
1917 symbolS *symp;
1919 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1920 resolve_symbol_value (symp);
1922 resolve_local_symbol_values ();
1923 resolve_reloc_expr_symbols ();
1925 PROGRESS (1);
1927 #ifdef tc_frob_file_before_adjust
1928 tc_frob_file_before_adjust ();
1929 #endif
1930 #ifdef obj_frob_file_before_adjust
1931 obj_frob_file_before_adjust ();
1932 #endif
1934 bfd_map_over_sections (stdoutput, adjust_reloc_syms, (char *) 0);
1936 #ifdef tc_frob_file_before_fix
1937 tc_frob_file_before_fix ();
1938 #endif
1939 #ifdef obj_frob_file_before_fix
1940 obj_frob_file_before_fix ();
1941 #endif
1943 bfd_map_over_sections (stdoutput, fix_segment, (char *) 0);
1945 /* Set up symbol table, and write it out. */
1946 if (symbol_rootP)
1948 symbolS *symp;
1949 bfd_boolean skip_next_symbol = FALSE;
1951 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
1953 int punt = 0;
1954 const char *name;
1956 if (skip_next_symbol)
1958 /* Don't do anything besides moving the value of the
1959 symbol from the GAS value-field to the BFD value-field. */
1960 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
1961 skip_next_symbol = FALSE;
1962 continue;
1965 if (symbol_mri_common_p (symp))
1967 if (S_IS_EXTERNAL (symp))
1968 as_bad (_("%s: global symbols not supported in common sections"),
1969 S_GET_NAME (symp));
1970 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
1971 continue;
1974 name = S_GET_NAME (symp);
1975 if (name)
1977 const char *name2 =
1978 decode_local_label_name ((char *) S_GET_NAME (symp));
1979 /* They only differ if `name' is a fb or dollar local
1980 label name. */
1981 if (name2 != name && ! S_IS_DEFINED (symp))
1982 as_bad (_("local label `%s' is not defined"), name2);
1985 /* Do it again, because adjust_reloc_syms might introduce
1986 more symbols. They'll probably only be section symbols,
1987 but they'll still need to have the values computed. */
1988 resolve_symbol_value (symp);
1990 /* Skip symbols which were equated to undefined or common
1991 symbols. */
1992 if (symbol_equated_reloc_p (symp)
1993 || S_IS_WEAKREFR (symp))
1995 const char *sname = S_GET_NAME (symp);
1997 if (S_IS_COMMON (symp)
1998 && !TC_FAKE_LABEL (sname)
1999 && !S_IS_WEAKREFR (symp)
2000 && (!S_IS_EXTERNAL (symp) || S_IS_LOCAL (symp)))
2002 expressionS *e = symbol_get_value_expression (symp);
2004 as_bad (_("Local symbol `%s' can't be equated to common symbol `%s'"),
2005 sname, S_GET_NAME (e->X_add_symbol));
2007 if (S_GET_SEGMENT (symp) == reg_section)
2009 /* Report error only if we know the symbol name. */
2010 if (S_GET_NAME (symp) != reg_section->name)
2011 as_bad (_("can't make global register symbol `%s'"),
2012 sname);
2014 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2015 continue;
2018 #ifdef obj_frob_symbol
2019 obj_frob_symbol (symp, punt);
2020 #endif
2021 #ifdef tc_frob_symbol
2022 if (! punt || symbol_used_in_reloc_p (symp))
2023 tc_frob_symbol (symp, punt);
2024 #endif
2026 /* If we don't want to keep this symbol, splice it out of
2027 the chain now. If EMIT_SECTION_SYMBOLS is 0, we never
2028 want section symbols. Otherwise, we skip local symbols
2029 and symbols that the frob_symbol macros told us to punt,
2030 but we keep such symbols if they are used in relocs. */
2031 if (symp == abs_section_sym
2032 || (! EMIT_SECTION_SYMBOLS
2033 && symbol_section_p (symp))
2034 /* Note that S_IS_EXTERNAL and S_IS_LOCAL are not always
2035 opposites. Sometimes the former checks flags and the
2036 latter examines the name... */
2037 || (!S_IS_EXTERNAL (symp)
2038 && (punt || S_IS_LOCAL (symp) ||
2039 (S_IS_WEAKREFD (symp) && ! symbol_used_p (symp)))
2040 && ! symbol_used_in_reloc_p (symp)))
2042 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2044 /* After symbol_remove, symbol_next(symp) still returns
2045 the one that came after it in the chain. So we don't
2046 need to do any extra cleanup work here. */
2047 continue;
2050 /* Make sure we really got a value for the symbol. */
2051 if (! symbol_resolved_p (symp))
2053 as_bad (_("can't resolve value for symbol `%s'"),
2054 S_GET_NAME (symp));
2055 symbol_mark_resolved (symp);
2058 /* Set the value into the BFD symbol. Up til now the value
2059 has only been kept in the gas symbolS struct. */
2060 symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
2062 /* A warning construct is a warning symbol followed by the
2063 symbol warned about. Don't let anything object-format or
2064 target-specific muck with it; it's ready for output. */
2065 if (symbol_get_bfdsym (symp)->flags & BSF_WARNING)
2066 skip_next_symbol = TRUE;
2070 PROGRESS (1);
2072 /* Now do any format-specific adjustments to the symbol table, such
2073 as adding file symbols. */
2074 #ifdef tc_adjust_symtab
2075 tc_adjust_symtab ();
2076 #endif
2077 #ifdef obj_adjust_symtab
2078 obj_adjust_symtab ();
2079 #endif
2081 /* Stop if there is an error. */
2082 if (had_errors ())
2083 return;
2085 /* Now that all the sizes are known, and contents correct, we can
2086 start writing to the file. */
2087 set_symtab ();
2089 /* If *_frob_file changes the symbol value at this point, it is
2090 responsible for moving the changed value into symp->bsym->value
2091 as well. Hopefully all symbol value changing can be done in
2092 *_frob_symbol. */
2093 #ifdef tc_frob_file
2094 tc_frob_file ();
2095 #endif
2096 #ifdef obj_frob_file
2097 obj_frob_file ();
2098 #endif
2099 #ifdef obj_coff_generate_pdata
2100 obj_coff_generate_pdata ();
2101 #endif
2102 bfd_map_over_sections (stdoutput, write_relocs, (char *) 0);
2104 #ifdef tc_frob_file_after_relocs
2105 tc_frob_file_after_relocs ();
2106 #endif
2107 #ifdef obj_frob_file_after_relocs
2108 obj_frob_file_after_relocs ();
2109 #endif
2111 /* Once all relocations have been written, we can compress the
2112 contents of the debug sections. This needs to be done before
2113 we start writing any sections, because it will affect the file
2114 layout, which is fixed once we start writing contents. */
2115 if (flag_compress_debug)
2116 bfd_map_over_sections (stdoutput, compress_debug, (char *) 0);
2118 bfd_map_over_sections (stdoutput, write_contents, (char *) 0);
2121 #ifdef TC_GENERIC_RELAX_TABLE
2122 /* Relax a fragment by scanning TC_GENERIC_RELAX_TABLE. */
2124 long
2125 relax_frag (segT segment, fragS *fragP, long stretch)
2127 const relax_typeS *this_type;
2128 const relax_typeS *start_type;
2129 relax_substateT next_state;
2130 relax_substateT this_state;
2131 offsetT growth;
2132 offsetT aim;
2133 addressT target;
2134 addressT address;
2135 symbolS *symbolP;
2136 const relax_typeS *table;
2138 target = fragP->fr_offset;
2139 address = fragP->fr_address;
2140 table = TC_GENERIC_RELAX_TABLE;
2141 this_state = fragP->fr_subtype;
2142 start_type = this_type = table + this_state;
2143 symbolP = fragP->fr_symbol;
2145 if (symbolP)
2147 fragS *sym_frag;
2149 sym_frag = symbol_get_frag (symbolP);
2151 #ifndef DIFF_EXPR_OK
2152 know (sym_frag != NULL);
2153 #endif
2154 know (S_GET_SEGMENT (symbolP) != absolute_section
2155 || sym_frag == &zero_address_frag);
2156 target += S_GET_VALUE (symbolP);
2158 /* If SYM_FRAG has yet to be reached on this pass, assume it
2159 will move by STRETCH just as we did, unless there is an
2160 alignment frag between here and SYM_FRAG. An alignment may
2161 well absorb any STRETCH, and we don't want to choose a larger
2162 branch insn by overestimating the needed reach of this
2163 branch. It isn't critical to calculate TARGET exactly; We
2164 know we'll be doing another pass if STRETCH is non-zero. */
2166 if (stretch != 0
2167 && sym_frag->relax_marker != fragP->relax_marker
2168 && S_GET_SEGMENT (symbolP) == segment)
2170 if (stretch < 0
2171 || sym_frag->region == fragP->region)
2172 target += stretch;
2173 /* If we get here we know we have a forward branch. This
2174 relax pass may have stretched previous instructions so
2175 far that omitting STRETCH would make the branch
2176 negative. Don't allow this in case the negative reach is
2177 large enough to require a larger branch instruction. */
2178 else if (target < address)
2179 target = fragP->fr_next->fr_address + stretch;
2183 aim = target - address - fragP->fr_fix;
2184 #ifdef TC_PCREL_ADJUST
2185 /* Currently only the ns32k family needs this. */
2186 aim += TC_PCREL_ADJUST (fragP);
2187 #endif
2189 #ifdef md_prepare_relax_scan
2190 /* Formerly called M68K_AIM_KLUDGE. */
2191 md_prepare_relax_scan (fragP, address, aim, this_state, this_type);
2192 #endif
2194 if (aim < 0)
2196 /* Look backwards. */
2197 for (next_state = this_type->rlx_more; next_state;)
2198 if (aim >= this_type->rlx_backward)
2199 next_state = 0;
2200 else
2202 /* Grow to next state. */
2203 this_state = next_state;
2204 this_type = table + this_state;
2205 next_state = this_type->rlx_more;
2208 else
2210 /* Look forwards. */
2211 for (next_state = this_type->rlx_more; next_state;)
2212 if (aim <= this_type->rlx_forward)
2213 next_state = 0;
2214 else
2216 /* Grow to next state. */
2217 this_state = next_state;
2218 this_type = table + this_state;
2219 next_state = this_type->rlx_more;
2223 growth = this_type->rlx_length - start_type->rlx_length;
2224 if (growth != 0)
2225 fragP->fr_subtype = this_state;
2226 return growth;
2229 #endif /* defined (TC_GENERIC_RELAX_TABLE) */
2231 /* Relax_align. Advance location counter to next address that has 'alignment'
2232 lowest order bits all 0s, return size of adjustment made. */
2233 static relax_addressT
2234 relax_align (register relax_addressT address, /* Address now. */
2235 register int alignment /* Alignment (binary). */)
2237 relax_addressT mask;
2238 relax_addressT new_address;
2240 mask = ~((~0) << alignment);
2241 new_address = (address + mask) & (~mask);
2242 #ifdef LINKER_RELAXING_SHRINKS_ONLY
2243 if (linkrelax)
2244 /* We must provide lots of padding, so the linker can discard it
2245 when needed. The linker will not add extra space, ever. */
2246 new_address += (1 << alignment);
2247 #endif
2248 return (new_address - address);
2251 /* Now we have a segment, not a crowd of sub-segments, we can make
2252 fr_address values.
2254 Relax the frags.
2256 After this, all frags in this segment have addresses that are correct
2257 within the segment. Since segments live in different file addresses,
2258 these frag addresses may not be the same as final object-file
2259 addresses. */
2262 relax_segment (struct frag *segment_frag_root, segT segment, int pass)
2264 unsigned long frag_count;
2265 struct frag *fragP;
2266 relax_addressT address;
2267 int region;
2268 int ret;
2270 /* In case md_estimate_size_before_relax() wants to make fixSs. */
2271 subseg_change (segment, 0);
2273 /* For each frag in segment: count and store (a 1st guess of)
2274 fr_address. */
2275 address = 0;
2276 region = 0;
2277 for (frag_count = 0, fragP = segment_frag_root;
2278 fragP;
2279 fragP = fragP->fr_next, frag_count ++)
2281 fragP->region = region;
2282 fragP->relax_marker = 0;
2283 fragP->fr_address = address;
2284 address += fragP->fr_fix;
2286 switch (fragP->fr_type)
2288 case rs_fill:
2289 address += fragP->fr_offset * fragP->fr_var;
2290 break;
2292 case rs_align:
2293 case rs_align_code:
2294 case rs_align_test:
2296 addressT offset = relax_align (address, (int) fragP->fr_offset);
2298 if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype)
2299 offset = 0;
2301 if (offset % fragP->fr_var != 0)
2303 as_bad_where (fragP->fr_file, fragP->fr_line,
2304 _("alignment padding (%lu bytes) not a multiple of %ld"),
2305 (unsigned long) offset, (long) fragP->fr_var);
2306 offset -= (offset % fragP->fr_var);
2309 address += offset;
2310 region += 1;
2312 break;
2314 case rs_org:
2315 /* Assume .org is nugatory. It will grow with 1st relax. */
2316 region += 1;
2317 break;
2319 case rs_space:
2320 break;
2322 case rs_machine_dependent:
2323 /* If fr_symbol is an expression, this call to
2324 resolve_symbol_value sets up the correct segment, which will
2325 likely be needed in md_estimate_size_before_relax. */
2326 if (fragP->fr_symbol)
2327 resolve_symbol_value (fragP->fr_symbol);
2329 address += md_estimate_size_before_relax (fragP, segment);
2330 break;
2332 #ifndef WORKING_DOT_WORD
2333 /* Broken words don't concern us yet. */
2334 case rs_broken_word:
2335 break;
2336 #endif
2338 case rs_leb128:
2339 /* Initial guess is always 1; doing otherwise can result in
2340 stable solutions that are larger than the minimum. */
2341 address += fragP->fr_offset = 1;
2342 break;
2344 case rs_cfa:
2345 address += eh_frame_estimate_size_before_relax (fragP);
2346 break;
2348 case rs_dwarf2dbg:
2349 address += dwarf2dbg_estimate_size_before_relax (fragP);
2350 break;
2352 default:
2353 BAD_CASE (fragP->fr_type);
2354 break;
2358 /* Do relax(). */
2360 unsigned long max_iterations;
2362 /* Cumulative address adjustment. */
2363 offsetT stretch;
2365 /* Have we made any adjustment this pass? We can't just test
2366 stretch because one piece of code may have grown and another
2367 shrank. */
2368 int stretched;
2370 /* Most horrible, but gcc may give us some exception data that
2371 is impossible to assemble, of the form
2373 .align 4
2374 .byte 0, 0
2375 .uleb128 end - start
2376 start:
2377 .space 128*128 - 1
2378 .align 4
2379 end:
2381 If the leb128 is two bytes in size, then end-start is 128*128,
2382 which requires a three byte leb128. If the leb128 is three
2383 bytes in size, then end-start is 128*128-1, which requires a
2384 two byte leb128. We work around this dilemma by inserting
2385 an extra 4 bytes of alignment just after the .align. This
2386 works because the data after the align is accessed relative to
2387 the end label.
2389 This counter is used in a tiny state machine to detect
2390 whether a leb128 followed by an align is impossible to
2391 relax. */
2392 int rs_leb128_fudge = 0;
2394 /* We want to prevent going into an infinite loop where one frag grows
2395 depending upon the location of a symbol which is in turn moved by
2396 the growing frag. eg:
2398 foo = .
2399 .org foo+16
2400 foo = .
2402 So we dictate that this algorithm can be at most O2. */
2403 max_iterations = frag_count * frag_count;
2404 /* Check for overflow. */
2405 if (max_iterations < frag_count)
2406 max_iterations = frag_count;
2408 ret = 0;
2411 stretch = 0;
2412 stretched = 0;
2414 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2416 offsetT growth = 0;
2417 addressT was_address;
2418 offsetT offset;
2419 symbolS *symbolP;
2421 fragP->relax_marker ^= 1;
2422 was_address = fragP->fr_address;
2423 address = fragP->fr_address += stretch;
2424 symbolP = fragP->fr_symbol;
2425 offset = fragP->fr_offset;
2427 switch (fragP->fr_type)
2429 case rs_fill: /* .fill never relaxes. */
2430 growth = 0;
2431 break;
2433 #ifndef WORKING_DOT_WORD
2434 /* JF: This is RMS's idea. I do *NOT* want to be blamed
2435 for it I do not want to write it. I do not want to have
2436 anything to do with it. This is not the proper way to
2437 implement this misfeature. */
2438 case rs_broken_word:
2440 struct broken_word *lie;
2441 struct broken_word *untruth;
2443 /* Yes this is ugly (storing the broken_word pointer
2444 in the symbol slot). Still, this whole chunk of
2445 code is ugly, and I don't feel like doing anything
2446 about it. Think of it as stubbornness in action. */
2447 growth = 0;
2448 for (lie = (struct broken_word *) (fragP->fr_symbol);
2449 lie && lie->dispfrag == fragP;
2450 lie = lie->next_broken_word)
2453 if (lie->added)
2454 continue;
2456 offset = (S_GET_VALUE (lie->add)
2457 + lie->addnum
2458 - S_GET_VALUE (lie->sub));
2459 if (offset <= -32768 || offset >= 32767)
2461 if (flag_warn_displacement)
2463 char buf[50];
2464 sprint_value (buf, (addressT) lie->addnum);
2465 as_warn_where (fragP->fr_file, fragP->fr_line,
2466 _(".word %s-%s+%s didn't fit"),
2467 S_GET_NAME (lie->add),
2468 S_GET_NAME (lie->sub),
2469 buf);
2471 if (fragP->fr_subtype == 0)
2473 fragP->fr_subtype++;
2474 growth += md_short_jump_size;
2477 /* Redirect *all* words of this table with the same
2478 target, lest we have to handle the case where the
2479 same target but with a offset that fits on this
2480 round overflows at the next relaxation round. */
2481 for (untruth = (struct broken_word *) (fragP->fr_symbol);
2482 untruth && untruth->dispfrag == lie->dispfrag;
2483 untruth = untruth->next_broken_word)
2484 if ((symbol_get_frag (untruth->add)
2485 == symbol_get_frag (lie->add))
2486 && (S_GET_VALUE (untruth->add)
2487 == S_GET_VALUE (lie->add)))
2489 untruth->added = 2;
2490 untruth->use_jump = lie;
2493 lie->added = 1;
2494 growth += md_long_jump_size;
2498 break;
2499 } /* case rs_broken_word */
2500 #endif
2501 case rs_align:
2502 case rs_align_code:
2503 case rs_align_test:
2505 addressT oldoff, newoff;
2507 oldoff = relax_align (was_address + fragP->fr_fix,
2508 (int) offset);
2509 newoff = relax_align (address + fragP->fr_fix,
2510 (int) offset);
2512 if (fragP->fr_subtype != 0)
2514 if (oldoff > fragP->fr_subtype)
2515 oldoff = 0;
2516 if (newoff > fragP->fr_subtype)
2517 newoff = 0;
2520 growth = newoff - oldoff;
2522 /* If this align happens to follow a leb128 and
2523 we have determined that the leb128 is bouncing
2524 in size, then break the cycle by inserting an
2525 extra alignment. */
2526 if (growth < 0
2527 && (rs_leb128_fudge & 16) != 0
2528 && (rs_leb128_fudge & 15) >= 2)
2530 segment_info_type *seginfo = seg_info (segment);
2531 struct obstack *ob = &seginfo->frchainP->frch_obstack;
2532 struct frag *newf;
2534 newf = frag_alloc (ob);
2535 obstack_blank_fast (ob, fragP->fr_var);
2536 obstack_finish (ob);
2537 memcpy (newf, fragP, SIZEOF_STRUCT_FRAG);
2538 memcpy (newf->fr_literal,
2539 fragP->fr_literal + fragP->fr_fix,
2540 fragP->fr_var);
2541 newf->fr_type = rs_fill;
2542 newf->fr_address = address + fragP->fr_fix + newoff;
2543 newf->fr_fix = 0;
2544 newf->fr_offset = (((offsetT) 1 << fragP->fr_offset)
2545 / fragP->fr_var);
2546 if (newf->fr_offset * newf->fr_var
2547 != (offsetT) 1 << fragP->fr_offset)
2549 newf->fr_offset = (offsetT) 1 << fragP->fr_offset;
2550 newf->fr_var = 1;
2552 /* Include size of new frag in GROWTH. */
2553 growth += newf->fr_offset * newf->fr_var;
2554 /* Adjust the new frag address for the amount
2555 we'll add when we process the new frag. */
2556 newf->fr_address -= stretch + growth;
2557 newf->relax_marker ^= 1;
2558 fragP->fr_next = newf;
2559 #ifdef DEBUG
2560 as_warn (_("padding added"));
2561 #endif
2564 break;
2566 case rs_org:
2568 addressT target = offset;
2569 addressT after;
2571 if (symbolP)
2573 /* Convert from an actual address to an octet offset
2574 into the section. Here it is assumed that the
2575 section's VMA is zero, and can omit subtracting it
2576 from the symbol's value to get the address offset. */
2577 know (S_GET_SEGMENT (symbolP)->vma == 0);
2578 target += S_GET_VALUE (symbolP) * OCTETS_PER_BYTE;
2581 know (fragP->fr_next);
2582 after = fragP->fr_next->fr_address + stretch;
2583 growth = target - after;
2584 if (growth < 0)
2586 growth = 0;
2588 /* Don't error on first few frag relax passes.
2589 The symbol might be an expression involving
2590 symbol values from other sections. If those
2591 sections have not yet been processed their
2592 frags will all have zero addresses, so we
2593 will calculate incorrect values for them. The
2594 number of passes we allow before giving an
2595 error is somewhat arbitrary. It should be at
2596 least one, with larger values requiring
2597 increasingly contrived dependencies between
2598 frags to trigger a false error. */
2599 if (pass < 2)
2601 /* Force another pass. */
2602 ret = 1;
2603 break;
2606 /* Growth may be negative, but variable part of frag
2607 cannot have fewer than 0 chars. That is, we can't
2608 .org backwards. */
2609 as_bad_where (fragP->fr_file, fragP->fr_line,
2610 _("attempt to move .org backwards"));
2612 /* We've issued an error message. Change the
2613 frag to avoid cascading errors. */
2614 fragP->fr_type = rs_align;
2615 fragP->fr_subtype = 0;
2616 fragP->fr_offset = 0;
2617 fragP->fr_fix = after - address;
2620 break;
2622 case rs_space:
2623 growth = 0;
2624 if (symbolP)
2626 offsetT amount;
2628 amount = S_GET_VALUE (symbolP);
2629 if (S_GET_SEGMENT (symbolP) != absolute_section
2630 || S_IS_COMMON (symbolP)
2631 || ! S_IS_DEFINED (symbolP))
2633 as_bad_where (fragP->fr_file, fragP->fr_line,
2634 _(".space specifies non-absolute value"));
2635 /* Prevent repeat of this error message. */
2636 fragP->fr_symbol = 0;
2638 else if (amount < 0)
2640 /* Don't error on first few frag relax passes.
2641 See rs_org comment for a longer explanation. */
2642 if (pass < 2)
2644 ret = 1;
2645 break;
2648 as_warn_where (fragP->fr_file, fragP->fr_line,
2649 _(".space or .fill with negative value, ignored"));
2650 fragP->fr_symbol = 0;
2652 else
2653 growth = (was_address + fragP->fr_fix + amount
2654 - fragP->fr_next->fr_address);
2656 break;
2658 case rs_machine_dependent:
2659 #ifdef md_relax_frag
2660 growth = md_relax_frag (segment, fragP, stretch);
2661 #else
2662 #ifdef TC_GENERIC_RELAX_TABLE
2663 /* The default way to relax a frag is to look through
2664 TC_GENERIC_RELAX_TABLE. */
2665 growth = relax_frag (segment, fragP, stretch);
2666 #endif /* TC_GENERIC_RELAX_TABLE */
2667 #endif
2668 break;
2670 case rs_leb128:
2672 valueT value;
2673 offsetT size;
2675 value = resolve_symbol_value (fragP->fr_symbol);
2676 size = sizeof_leb128 (value, fragP->fr_subtype);
2677 growth = size - fragP->fr_offset;
2678 fragP->fr_offset = size;
2680 break;
2682 case rs_cfa:
2683 growth = eh_frame_relax_frag (fragP);
2684 break;
2686 case rs_dwarf2dbg:
2687 growth = dwarf2dbg_relax_frag (fragP);
2688 break;
2690 default:
2691 BAD_CASE (fragP->fr_type);
2692 break;
2694 if (growth)
2696 stretch += growth;
2697 stretched = 1;
2698 if (fragP->fr_type == rs_leb128)
2699 rs_leb128_fudge += 16;
2700 else if (fragP->fr_type == rs_align
2701 && (rs_leb128_fudge & 16) != 0
2702 && stretch == 0)
2703 rs_leb128_fudge += 16;
2704 else
2705 rs_leb128_fudge = 0;
2709 if (stretch == 0
2710 && (rs_leb128_fudge & 16) == 0
2711 && (rs_leb128_fudge & -16) != 0)
2712 rs_leb128_fudge += 1;
2713 else
2714 rs_leb128_fudge = 0;
2716 /* Until nothing further to relax. */
2717 while (stretched && -- max_iterations);
2719 if (stretched)
2720 as_fatal (_("Infinite loop encountered whilst attempting to compute the addresses of symbols in section %s"),
2721 segment_name (segment));
2724 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
2725 if (fragP->last_fr_address != fragP->fr_address)
2727 fragP->last_fr_address = fragP->fr_address;
2728 ret = 1;
2730 return ret;
2733 void
2734 number_to_chars_bigendian (char *buf, valueT val, int n)
2736 if (n <= 0)
2737 abort ();
2738 while (n--)
2740 buf[n] = val & 0xff;
2741 val >>= 8;
2745 void
2746 number_to_chars_littleendian (char *buf, valueT val, int n)
2748 if (n <= 0)
2749 abort ();
2750 while (n--)
2752 *buf++ = val & 0xff;
2753 val >>= 8;
2757 void
2758 write_print_statistics (FILE *file)
2760 fprintf (file, "fixups: %d\n", n_fixups);
2763 /* For debugging. */
2764 extern int indent_level;
2766 void
2767 print_fixup (fixS *fixp)
2769 indent_level = 1;
2770 fprintf (stderr, "fix ");
2771 fprintf_vma (stderr, (bfd_vma)((bfd_hostptr_t) fixp));
2772 fprintf (stderr, " %s:%d",fixp->fx_file, fixp->fx_line);
2773 if (fixp->fx_pcrel)
2774 fprintf (stderr, " pcrel");
2775 if (fixp->fx_pcrel_adjust)
2776 fprintf (stderr, " pcrel_adjust=%d", fixp->fx_pcrel_adjust);
2777 if (fixp->fx_im_disp)
2779 #ifdef TC_NS32K
2780 fprintf (stderr, " im_disp=%d", fixp->fx_im_disp);
2781 #else
2782 fprintf (stderr, " im_disp");
2783 #endif
2785 if (fixp->fx_tcbit)
2786 fprintf (stderr, " tcbit");
2787 if (fixp->fx_done)
2788 fprintf (stderr, " done");
2789 fprintf (stderr, "\n size=%d frag=", fixp->fx_size);
2790 fprintf_vma (stderr, (bfd_vma) ((bfd_hostptr_t) fixp->fx_frag));
2791 fprintf (stderr, " where=%ld offset=%lx addnumber=%lx",
2792 (long) fixp->fx_where,
2793 (unsigned long) fixp->fx_offset,
2794 (unsigned long) fixp->fx_addnumber);
2795 fprintf (stderr, "\n %s (%d)", bfd_get_reloc_code_name (fixp->fx_r_type),
2796 fixp->fx_r_type);
2797 if (fixp->fx_addsy)
2799 fprintf (stderr, "\n +<");
2800 print_symbol_value_1 (stderr, fixp->fx_addsy);
2801 fprintf (stderr, ">");
2803 if (fixp->fx_subsy)
2805 fprintf (stderr, "\n -<");
2806 print_symbol_value_1 (stderr, fixp->fx_subsy);
2807 fprintf (stderr, ">");
2809 fprintf (stderr, "\n");
2810 #ifdef TC_FIX_DATA_PRINT
2811 TC_FIX_DATA_PRINT (stderr, fixp);
2812 #endif