PR 10893
[deliverable/binutils-gdb.git] / gold / target-reloc.h
1 // target-reloc.h -- target specific relocation support -*- C++ -*-
2
3 // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
5
6 // This file is part of gold.
7
8 // This program 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 of the License, or
11 // (at your option) any later version.
12
13 // This program 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.
17
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
22
23 #ifndef GOLD_TARGET_RELOC_H
24 #define GOLD_TARGET_RELOC_H
25
26 #include "elfcpp.h"
27 #include "symtab.h"
28 #include "object.h"
29 #include "reloc.h"
30 #include "reloc-types.h"
31
32 namespace gold
33 {
34
35 // This function implements the generic part of reloc scanning. The
36 // template parameter Scan must be a class type which provides two
37 // functions: local() and global(). Those functions implement the
38 // machine specific part of scanning. We do it this way to
39 // avoidmaking a function call for each relocation, and to avoid
40 // repeating the generic code for each target.
41
42 template<int size, bool big_endian, typename Target_type, int sh_type,
43 typename Scan>
44 inline void
45 scan_relocs(
46 Symbol_table* symtab,
47 Layout* layout,
48 Target_type* target,
49 Sized_relobj<size, big_endian>* object,
50 unsigned int data_shndx,
51 const unsigned char* prelocs,
52 size_t reloc_count,
53 Output_section* output_section,
54 bool needs_special_offset_handling,
55 size_t local_count,
56 const unsigned char* plocal_syms)
57 {
58 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
59 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
60 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
61 Scan scan;
62
63 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
64 {
65 Reltype reloc(prelocs);
66
67 if (needs_special_offset_handling
68 && !output_section->is_input_address_mapped(object, data_shndx,
69 reloc.get_r_offset()))
70 continue;
71
72 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
73 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
74 unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
75
76 if (r_sym < local_count)
77 {
78 gold_assert(plocal_syms != NULL);
79 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
80 + r_sym * sym_size);
81 unsigned int shndx = lsym.get_st_shndx();
82 bool is_ordinary;
83 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
84 if (is_ordinary
85 && shndx != elfcpp::SHN_UNDEF
86 && !object->is_section_included(shndx)
87 && !symtab->is_section_folded(object, shndx))
88 {
89 // RELOC is a relocation against a local symbol in a
90 // section we are discarding. We can ignore this
91 // relocation. It will eventually become a reloc
92 // against the value zero.
93 //
94 // FIXME: We should issue a warning if this is an
95 // allocated section; is this the best place to do it?
96 //
97 // FIXME: The old GNU linker would in some cases look
98 // for the linkonce section which caused this section to
99 // be discarded, and, if the other section was the same
100 // size, change the reloc to refer to the other section.
101 // That seems risky and weird to me, and I don't know of
102 // any case where it is actually required.
103
104 continue;
105 }
106 scan.local(symtab, layout, target, object, data_shndx,
107 output_section, reloc, r_type, lsym);
108 }
109 else
110 {
111 Symbol* gsym = object->global_symbol(r_sym);
112 gold_assert(gsym != NULL);
113 if (gsym->is_forwarder())
114 gsym = symtab->resolve_forwards(gsym);
115
116 scan.global(symtab, layout, target, object, data_shndx,
117 output_section, reloc, r_type, gsym);
118 }
119 }
120 }
121
122 // Behavior for relocations to discarded comdat sections.
123
124 enum Comdat_behavior
125 {
126 CB_UNDETERMINED, // Not yet determined -- need to look at section name.
127 CB_PRETEND, // Attempt to map to the corresponding kept section.
128 CB_IGNORE, // Ignore the relocation.
129 CB_WARNING // Print a warning.
130 };
131
132 // Decide what the linker should do for relocations that refer to discarded
133 // comdat sections. This decision is based on the name of the section being
134 // relocated.
135
136 inline Comdat_behavior
137 get_comdat_behavior(const char* name)
138 {
139 if (Layout::is_debug_info_section(name))
140 return CB_PRETEND;
141 if (strcmp(name, ".eh_frame") == 0
142 || strcmp(name, ".gcc_except_table") == 0)
143 return CB_IGNORE;
144 return CB_WARNING;
145 }
146
147 // Give an error for a symbol with non-default visibility which is not
148 // defined locally.
149
150 inline void
151 visibility_error(const Symbol* sym)
152 {
153 const char* v;
154 switch (sym->visibility())
155 {
156 case elfcpp::STV_INTERNAL:
157 v = _("internal");
158 break;
159 case elfcpp::STV_HIDDEN:
160 v = _("hidden");
161 break;
162 case elfcpp::STV_PROTECTED:
163 v = _("protected");
164 break;
165 default:
166 gold_unreachable();
167 }
168 gold_error(_("%s symbol '%s' is not defined locally"),
169 v, sym->name());
170 }
171
172 // This function implements the generic part of relocation processing.
173 // The template parameter Relocate must be a class type which provides
174 // a single function, relocate(), which implements the machine
175 // specific part of a relocation.
176
177 // SIZE is the ELF size: 32 or 64. BIG_ENDIAN is the endianness of
178 // the data. SH_TYPE is the section type: SHT_REL or SHT_RELA.
179 // RELOCATE implements operator() to do a relocation.
180
181 // PRELOCS points to the relocation data. RELOC_COUNT is the number
182 // of relocs. OUTPUT_SECTION is the output section.
183 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
184 // mapped to output offsets.
185
186 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
187 // VIEW_SIZE is the size. These refer to the input section, unless
188 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
189 // the output section.
190
191 // RELOC_SYMBOL_CHANGES is used for -fsplit-stack support. If it is
192 // not NULL, it is a vector indexed by relocation index. If that
193 // entry is not NULL, it points to a global symbol which used as the
194 // symbol for the relocation, ignoring the symbol index in the
195 // relocation.
196
197 template<int size, bool big_endian, typename Target_type, int sh_type,
198 typename Relocate>
199 inline void
200 relocate_section(
201 const Relocate_info<size, big_endian>* relinfo,
202 Target_type* target,
203 const unsigned char* prelocs,
204 size_t reloc_count,
205 Output_section* output_section,
206 bool needs_special_offset_handling,
207 unsigned char* view,
208 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
209 section_size_type view_size,
210 const Reloc_symbol_changes* reloc_symbol_changes)
211 {
212 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
213 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
214 Relocate relocate;
215
216 Sized_relobj<size, big_endian>* object = relinfo->object;
217 unsigned int local_count = object->local_symbol_count();
218
219 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
220
221 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
222 {
223 Reltype reloc(prelocs);
224
225 section_offset_type offset =
226 convert_to_section_size_type(reloc.get_r_offset());
227
228 if (needs_special_offset_handling)
229 {
230 offset = output_section->output_offset(relinfo->object,
231 relinfo->data_shndx,
232 offset);
233 if (offset == -1)
234 continue;
235 }
236
237 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
238 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
239 unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
240
241 const Sized_symbol<size>* sym;
242
243 Symbol_value<size> symval;
244 const Symbol_value<size> *psymval;
245 bool is_defined_in_discarded_section;
246 unsigned int shndx;
247 if (r_sym < local_count
248 && (reloc_symbol_changes == NULL
249 || (*reloc_symbol_changes)[i] == NULL))
250 {
251 sym = NULL;
252 psymval = object->local_symbol(r_sym);
253
254 // If the local symbol belongs to a section we are discarding,
255 // and that section is a debug section, try to find the
256 // corresponding kept section and map this symbol to its
257 // counterpart in the kept section. The symbol must not
258 // correspond to a section we are folding.
259 bool is_ordinary;
260 shndx = psymval->input_shndx(&is_ordinary);
261 is_defined_in_discarded_section =
262 (is_ordinary
263 && shndx != elfcpp::SHN_UNDEF
264 && !object->is_section_included(shndx)
265 && !relinfo->symtab->is_section_folded(object, shndx));
266 }
267 else
268 {
269 const Symbol* gsym;
270 if (reloc_symbol_changes != NULL
271 && (*reloc_symbol_changes)[i] != NULL)
272 gsym = (*reloc_symbol_changes)[i];
273 else
274 {
275 gsym = object->global_symbol(r_sym);
276 gold_assert(gsym != NULL);
277 if (gsym->is_forwarder())
278 gsym = relinfo->symtab->resolve_forwards(gsym);
279 }
280
281 sym = static_cast<const Sized_symbol<size>*>(gsym);
282 if (sym->has_symtab_index() && sym->symtab_index() != -1U)
283 symval.set_output_symtab_index(sym->symtab_index());
284 else
285 symval.set_no_output_symtab_entry();
286 symval.set_output_value(sym->value());
287 if (gsym->type() == elfcpp::STT_TLS)
288 symval.set_is_tls_symbol();
289 else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
290 symval.set_is_ifunc_symbol();
291 psymval = &symval;
292
293 is_defined_in_discarded_section =
294 (gsym->is_defined_in_discarded_section()
295 && gsym->is_undefined());
296 shndx = 0;
297 }
298
299 Symbol_value<size> symval2;
300 if (is_defined_in_discarded_section)
301 {
302 if (comdat_behavior == CB_UNDETERMINED)
303 {
304 std::string name = object->section_name(relinfo->data_shndx);
305 comdat_behavior = get_comdat_behavior(name.c_str());
306 }
307 if (comdat_behavior == CB_PRETEND)
308 {
309 // FIXME: This case does not work for global symbols.
310 // We have no place to store the original section index.
311 // Fortunately this does not matter for comdat sections,
312 // only for sections explicitly discarded by a linker
313 // script.
314 bool found;
315 typename elfcpp::Elf_types<size>::Elf_Addr value =
316 object->map_to_kept_section(shndx, &found);
317 if (found)
318 symval2.set_output_value(value + psymval->input_value());
319 else
320 symval2.set_output_value(0);
321 }
322 else
323 {
324 if (comdat_behavior == CB_WARNING)
325 gold_warning_at_location(relinfo, i, offset,
326 _("relocation refers to discarded "
327 "section"));
328 symval2.set_output_value(0);
329 }
330 symval2.set_no_output_symtab_entry();
331 psymval = &symval2;
332 }
333
334 if (!relocate.relocate(relinfo, target, output_section, i, reloc,
335 r_type, sym, psymval, view + offset,
336 view_address + offset, view_size))
337 continue;
338
339 if (offset < 0 || static_cast<section_size_type>(offset) >= view_size)
340 {
341 gold_error_at_location(relinfo, i, offset,
342 _("reloc has bad offset %zu"),
343 static_cast<size_t>(offset));
344 continue;
345 }
346
347 if (sym != NULL
348 && (sym->is_undefined() || sym->is_placeholder())
349 && sym->binding() != elfcpp::STB_WEAK
350 && !is_defined_in_discarded_section
351 && !target->is_defined_by_abi(sym)
352 && (!parameters->options().shared() // -shared
353 || parameters->options().defs())) // -z defs
354 gold_undefined_symbol_at_location(sym, relinfo, i, offset);
355 else if (sym != NULL
356 && sym->visibility() != elfcpp::STV_DEFAULT
357 && (sym->is_undefined() || sym->is_from_dynobj()))
358 visibility_error(sym);
359
360 if (sym != NULL && sym->has_warning())
361 relinfo->symtab->issue_warning(sym, relinfo, i, offset);
362 }
363 }
364
365 // This class may be used as a typical class for the
366 // Scan_relocatable_reloc parameter to scan_relocatable_relocs. The
367 // template parameter Classify_reloc must be a class type which
368 // provides a function get_size_for_reloc which returns the number of
369 // bytes to which a reloc applies. This class is intended to capture
370 // the most typical target behaviour, while still permitting targets
371 // to define their own independent class for Scan_relocatable_reloc.
372
373 template<int sh_type, typename Classify_reloc>
374 class Default_scan_relocatable_relocs
375 {
376 public:
377 // Return the strategy to use for a local symbol which is not a
378 // section symbol, given the relocation type.
379 inline Relocatable_relocs::Reloc_strategy
380 local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym)
381 {
382 // We assume that relocation type 0 is NONE. Targets which are
383 // different must override.
384 if (r_type == 0 && r_sym == 0)
385 return Relocatable_relocs::RELOC_DISCARD;
386 return Relocatable_relocs::RELOC_COPY;
387 }
388
389 // Return the strategy to use for a local symbol which is a section
390 // symbol, given the relocation type.
391 inline Relocatable_relocs::Reloc_strategy
392 local_section_strategy(unsigned int r_type, Relobj* object)
393 {
394 if (sh_type == elfcpp::SHT_RELA)
395 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
396 else
397 {
398 Classify_reloc classify;
399 switch (classify.get_size_for_reloc(r_type, object))
400 {
401 case 0:
402 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
403 case 1:
404 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1;
405 case 2:
406 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2;
407 case 4:
408 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
409 case 8:
410 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8;
411 default:
412 gold_unreachable();
413 }
414 }
415 }
416
417 // Return the strategy to use for a global symbol, given the
418 // relocation type, the object, and the symbol index.
419 inline Relocatable_relocs::Reloc_strategy
420 global_strategy(unsigned int, Relobj*, unsigned int)
421 { return Relocatable_relocs::RELOC_COPY; }
422 };
423
424 // Scan relocs during a relocatable link. This is a default
425 // definition which should work for most targets.
426 // Scan_relocatable_reloc must name a class type which provides three
427 // functions which return a Relocatable_relocs::Reloc_strategy code:
428 // global_strategy, local_non_section_strategy, and
429 // local_section_strategy. Most targets should be able to use
430 // Default_scan_relocatable_relocs as this class.
431
432 template<int size, bool big_endian, int sh_type,
433 typename Scan_relocatable_reloc>
434 void
435 scan_relocatable_relocs(
436 Symbol_table*,
437 Layout*,
438 Sized_relobj<size, big_endian>* object,
439 unsigned int data_shndx,
440 const unsigned char* prelocs,
441 size_t reloc_count,
442 Output_section* output_section,
443 bool needs_special_offset_handling,
444 size_t local_symbol_count,
445 const unsigned char* plocal_syms,
446 Relocatable_relocs* rr)
447 {
448 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
449 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
450 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
451 Scan_relocatable_reloc scan;
452
453 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
454 {
455 Reltype reloc(prelocs);
456
457 Relocatable_relocs::Reloc_strategy strategy;
458
459 if (needs_special_offset_handling
460 && !output_section->is_input_address_mapped(object, data_shndx,
461 reloc.get_r_offset()))
462 strategy = Relocatable_relocs::RELOC_DISCARD;
463 else
464 {
465 typename elfcpp::Elf_types<size>::Elf_WXword r_info =
466 reloc.get_r_info();
467 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
468 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
469
470 if (r_sym >= local_symbol_count)
471 strategy = scan.global_strategy(r_type, object, r_sym);
472 else
473 {
474 gold_assert(plocal_syms != NULL);
475 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
476 + r_sym * sym_size);
477 unsigned int shndx = lsym.get_st_shndx();
478 bool is_ordinary;
479 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
480 if (is_ordinary
481 && shndx != elfcpp::SHN_UNDEF
482 && !object->is_section_included(shndx))
483 {
484 // RELOC is a relocation against a local symbol
485 // defined in a section we are discarding. Discard
486 // the reloc. FIXME: Should we issue a warning?
487 strategy = Relocatable_relocs::RELOC_DISCARD;
488 }
489 else if (lsym.get_st_type() != elfcpp::STT_SECTION)
490 strategy = scan.local_non_section_strategy(r_type, object,
491 r_sym);
492 else
493 {
494 strategy = scan.local_section_strategy(r_type, object);
495 if (strategy != Relocatable_relocs::RELOC_DISCARD)
496 object->output_section(shndx)->set_needs_symtab_index();
497 }
498
499 if (strategy == Relocatable_relocs::RELOC_COPY)
500 object->set_must_have_output_symtab_entry(r_sym);
501 }
502 }
503
504 rr->set_next_reloc_strategy(strategy);
505 }
506 }
507
508 // Relocate relocs during a relocatable link. This is a default
509 // definition which should work for most targets.
510
511 template<int size, bool big_endian, int sh_type>
512 void
513 relocate_for_relocatable(
514 const Relocate_info<size, big_endian>* relinfo,
515 const unsigned char* prelocs,
516 size_t reloc_count,
517 Output_section* output_section,
518 typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
519 const Relocatable_relocs* rr,
520 unsigned char* view,
521 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
522 section_size_type view_size,
523 unsigned char* reloc_view,
524 section_size_type reloc_view_size)
525 {
526 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
527 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
528 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc_write
529 Reltype_write;
530 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
531 const Address invalid_address = static_cast<Address>(0) - 1;
532
533 Sized_relobj<size, big_endian>* const object = relinfo->object;
534 const unsigned int local_count = object->local_symbol_count();
535
536 unsigned char* pwrite = reloc_view;
537
538 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
539 {
540 Relocatable_relocs::Reloc_strategy strategy = rr->strategy(i);
541 if (strategy == Relocatable_relocs::RELOC_DISCARD)
542 continue;
543
544 if (strategy == Relocatable_relocs::RELOC_SPECIAL)
545 {
546 // Target wants to handle this relocation.
547 Sized_target<size, big_endian>* target =
548 parameters->sized_target<size, big_endian>();
549 target->relocate_special_relocatable(relinfo, sh_type, prelocs,
550 i, output_section,
551 offset_in_output_section,
552 view, view_address,
553 view_size, pwrite);
554 pwrite += reloc_size;
555 continue;
556 }
557 Reltype reloc(prelocs);
558 Reltype_write reloc_write(pwrite);
559
560 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
561 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
562 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
563
564 // Get the new symbol index.
565
566 unsigned int new_symndx;
567 if (r_sym < local_count)
568 {
569 switch (strategy)
570 {
571 case Relocatable_relocs::RELOC_COPY:
572 if (r_sym == 0)
573 new_symndx = 0;
574 else
575 {
576 new_symndx = object->symtab_index(r_sym);
577 gold_assert(new_symndx != -1U);
578 }
579 break;
580
581 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
582 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
583 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
584 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
585 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
586 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
587 {
588 // We are adjusting a section symbol. We need to find
589 // the symbol table index of the section symbol for
590 // the output section corresponding to input section
591 // in which this symbol is defined.
592 gold_assert(r_sym < local_count);
593 bool is_ordinary;
594 unsigned int shndx =
595 object->local_symbol_input_shndx(r_sym, &is_ordinary);
596 gold_assert(is_ordinary);
597 Output_section* os = object->output_section(shndx);
598 gold_assert(os != NULL);
599 gold_assert(os->needs_symtab_index());
600 new_symndx = os->symtab_index();
601 }
602 break;
603
604 default:
605 gold_unreachable();
606 }
607 }
608 else
609 {
610 const Symbol* gsym = object->global_symbol(r_sym);
611 gold_assert(gsym != NULL);
612 if (gsym->is_forwarder())
613 gsym = relinfo->symtab->resolve_forwards(gsym);
614
615 gold_assert(gsym->has_symtab_index());
616 new_symndx = gsym->symtab_index();
617 }
618
619 // Get the new offset--the location in the output section where
620 // this relocation should be applied.
621
622 Address offset = reloc.get_r_offset();
623 Address new_offset;
624 if (offset_in_output_section != invalid_address)
625 new_offset = offset + offset_in_output_section;
626 else
627 {
628 section_offset_type sot_offset =
629 convert_types<section_offset_type, Address>(offset);
630 section_offset_type new_sot_offset =
631 output_section->output_offset(object, relinfo->data_shndx,
632 sot_offset);
633 gold_assert(new_sot_offset != -1);
634 new_offset = new_sot_offset;
635 }
636
637 // In an object file, r_offset is an offset within the section.
638 // In an executable or dynamic object, generated by
639 // --emit-relocs, r_offset is an absolute address.
640 if (!parameters->options().relocatable())
641 {
642 new_offset += view_address;
643 if (offset_in_output_section != invalid_address)
644 new_offset -= offset_in_output_section;
645 }
646
647 reloc_write.put_r_offset(new_offset);
648 reloc_write.put_r_info(elfcpp::elf_r_info<size>(new_symndx, r_type));
649
650 // Handle the reloc addend based on the strategy.
651
652 if (strategy == Relocatable_relocs::RELOC_COPY)
653 {
654 if (sh_type == elfcpp::SHT_RELA)
655 Reloc_types<sh_type, size, big_endian>::
656 copy_reloc_addend(&reloc_write,
657 &reloc);
658 }
659 else
660 {
661 // The relocation uses a section symbol in the input file.
662 // We are adjusting it to use a section symbol in the output
663 // file. The input section symbol refers to some address in
664 // the input section. We need the relocation in the output
665 // file to refer to that same address. This adjustment to
666 // the addend is the same calculation we use for a simple
667 // absolute relocation for the input section symbol.
668
669 const Symbol_value<size>* psymval = object->local_symbol(r_sym);
670
671 unsigned char* padd = view + offset;
672 switch (strategy)
673 {
674 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
675 {
676 typename elfcpp::Elf_types<size>::Elf_Swxword addend;
677 addend = Reloc_types<sh_type, size, big_endian>::
678 get_reloc_addend(&reloc);
679 addend = psymval->value(object, addend);
680 Reloc_types<sh_type, size, big_endian>::
681 set_reloc_addend(&reloc_write, addend);
682 }
683 break;
684
685 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
686 break;
687
688 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
689 Relocate_functions<size, big_endian>::rel8(padd, object,
690 psymval);
691 break;
692
693 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
694 Relocate_functions<size, big_endian>::rel16(padd, object,
695 psymval);
696 break;
697
698 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
699 Relocate_functions<size, big_endian>::rel32(padd, object,
700 psymval);
701 break;
702
703 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
704 Relocate_functions<size, big_endian>::rel64(padd, object,
705 psymval);
706 break;
707
708 default:
709 gold_unreachable();
710 }
711 }
712
713 pwrite += reloc_size;
714 }
715
716 gold_assert(static_cast<section_size_type>(pwrite - reloc_view)
717 == reloc_view_size);
718 }
719
720 } // End namespace gold.
721
722 #endif // !defined(GOLD_TARGET_RELOC_H)
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