gas/
[binutils.git] / gold / reloc.cc
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1 // reloc.cc -- relocate input files for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
23 #include "gold.h"
25 #include <algorithm>
27 #include "workqueue.h"
28 #include "layout.h"
29 #include "symtab.h"
30 #include "output.h"
31 #include "merge.h"
32 #include "object.h"
33 #include "target-reloc.h"
34 #include "reloc.h"
35 #include "icf.h"
36 #include "compressed_output.h"
37 #include "incremental.h"
39 namespace gold
42 // Read_relocs methods.
44 // These tasks just read the relocation information from the file.
45 // After reading it, the start another task to process the
46 // information. These tasks requires access to the file.
48 Task_token*
49 Read_relocs::is_runnable()
51 return this->object_->is_locked() ? this->object_->token() : NULL;
54 // Lock the file.
56 void
57 Read_relocs::locks(Task_locker* tl)
59 Task_token* token = this->object_->token();
60 if (token != NULL)
61 tl->add(this, token);
64 // Read the relocations and then start a Scan_relocs_task.
66 void
67 Read_relocs::run(Workqueue* workqueue)
69 Read_relocs_data* rd = new Read_relocs_data;
70 this->object_->read_relocs(rd);
71 this->object_->set_relocs_data(rd);
72 this->object_->release();
74 // If garbage collection or identical comdat folding is desired, we
75 // process the relocs first before scanning them. Scanning of relocs is
76 // done only after garbage or identical sections is identified.
77 if (parameters->options().gc_sections()
78 || parameters->options().icf_enabled())
80 workqueue->queue_next(new Gc_process_relocs(this->symtab_,
81 this->layout_,
82 this->object_, rd,
83 this->this_blocker_,
84 this->next_blocker_));
86 else
88 workqueue->queue_next(new Scan_relocs(this->symtab_, this->layout_,
89 this->object_, rd,
90 this->this_blocker_,
91 this->next_blocker_));
95 // Return a debugging name for the task.
97 std::string
98 Read_relocs::get_name() const
100 return "Read_relocs " + this->object_->name();
103 // Gc_process_relocs methods.
105 Gc_process_relocs::~Gc_process_relocs()
107 if (this->this_blocker_ != NULL)
108 delete this->this_blocker_;
111 // These tasks process the relocations read by Read_relocs and
112 // determine which sections are referenced and which are garbage.
113 // This task is done only when --gc-sections is used. This is blocked
114 // by THIS_BLOCKER_. It unblocks NEXT_BLOCKER_.
116 Task_token*
117 Gc_process_relocs::is_runnable()
119 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
120 return this->this_blocker_;
121 if (this->object_->is_locked())
122 return this->object_->token();
123 return NULL;
126 void
127 Gc_process_relocs::locks(Task_locker* tl)
129 tl->add(this, this->object_->token());
130 tl->add(this, this->next_blocker_);
133 void
134 Gc_process_relocs::run(Workqueue*)
136 this->object_->gc_process_relocs(this->symtab_, this->layout_, this->rd_);
137 this->object_->release();
140 // Return a debugging name for the task.
142 std::string
143 Gc_process_relocs::get_name() const
145 return "Gc_process_relocs " + this->object_->name();
148 // Scan_relocs methods.
150 Scan_relocs::~Scan_relocs()
152 if (this->this_blocker_ != NULL)
153 delete this->this_blocker_;
156 // These tasks scan the relocations read by Read_relocs and mark up
157 // the symbol table to indicate which relocations are required. We
158 // use a lock on the symbol table to keep them from interfering with
159 // each other.
161 Task_token*
162 Scan_relocs::is_runnable()
164 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
165 return this->this_blocker_;
166 if (this->object_->is_locked())
167 return this->object_->token();
168 return NULL;
171 // Return the locks we hold: one on the file, one on the symbol table
172 // and one blocker.
174 void
175 Scan_relocs::locks(Task_locker* tl)
177 Task_token* token = this->object_->token();
178 if (token != NULL)
179 tl->add(this, token);
180 tl->add(this, this->next_blocker_);
183 // Scan the relocs.
185 void
186 Scan_relocs::run(Workqueue*)
188 this->object_->scan_relocs(this->symtab_, this->layout_, this->rd_);
189 delete this->rd_;
190 this->rd_ = NULL;
191 this->object_->release();
194 // Return a debugging name for the task.
196 std::string
197 Scan_relocs::get_name() const
199 return "Scan_relocs " + this->object_->name();
202 // Relocate_task methods.
204 // We may have to wait for the output sections to be written.
206 Task_token*
207 Relocate_task::is_runnable()
209 if (this->object_->relocs_must_follow_section_writes()
210 && this->output_sections_blocker_->is_blocked())
211 return this->output_sections_blocker_;
213 if (this->object_->is_locked())
214 return this->object_->token();
216 return NULL;
219 // We want to lock the file while we run. We want to unblock
220 // INPUT_SECTIONS_BLOCKER and FINAL_BLOCKER when we are done.
221 // INPUT_SECTIONS_BLOCKER may be NULL.
223 void
224 Relocate_task::locks(Task_locker* tl)
226 if (this->input_sections_blocker_ != NULL)
227 tl->add(this, this->input_sections_blocker_);
228 tl->add(this, this->final_blocker_);
229 Task_token* token = this->object_->token();
230 if (token != NULL)
231 tl->add(this, token);
234 // Run the task.
236 void
237 Relocate_task::run(Workqueue*)
239 this->object_->relocate(this->symtab_, this->layout_, this->of_);
241 // This is normally the last thing we will do with an object, so
242 // uncache all views.
243 this->object_->clear_view_cache_marks();
245 this->object_->release();
248 // Return a debugging name for the task.
250 std::string
251 Relocate_task::get_name() const
253 return "Relocate_task " + this->object_->name();
256 // Read the relocs and local symbols from the object file and store
257 // the information in RD.
259 template<int size, bool big_endian>
260 void
261 Sized_relobj_file<size, big_endian>::do_read_relocs(Read_relocs_data* rd)
263 rd->relocs.clear();
265 unsigned int shnum = this->shnum();
266 if (shnum == 0)
267 return;
269 rd->relocs.reserve(shnum / 2);
271 const Output_sections& out_sections(this->output_sections());
272 const std::vector<Address>& out_offsets(this->section_offsets());
274 const unsigned char* pshdrs = this->get_view(this->elf_file_.shoff(),
275 shnum * This::shdr_size,
276 true, true);
277 // Skip the first, dummy, section.
278 const unsigned char* ps = pshdrs + This::shdr_size;
279 for (unsigned int i = 1; i < shnum; ++i, ps += This::shdr_size)
281 typename This::Shdr shdr(ps);
283 unsigned int sh_type = shdr.get_sh_type();
284 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
285 continue;
287 unsigned int shndx = this->adjust_shndx(shdr.get_sh_info());
288 if (shndx >= shnum)
290 this->error(_("relocation section %u has bad info %u"),
291 i, shndx);
292 continue;
295 Output_section* os = out_sections[shndx];
296 if (os == NULL)
297 continue;
299 // We are scanning relocations in order to fill out the GOT and
300 // PLT sections. Relocations for sections which are not
301 // allocated (typically debugging sections) should not add new
302 // GOT and PLT entries. So we skip them unless this is a
303 // relocatable link or we need to emit relocations. FIXME: What
304 // should we do if a linker script maps a section with SHF_ALLOC
305 // clear to a section with SHF_ALLOC set?
306 typename This::Shdr secshdr(pshdrs + shndx * This::shdr_size);
307 bool is_section_allocated = ((secshdr.get_sh_flags() & elfcpp::SHF_ALLOC)
308 != 0);
309 if (!is_section_allocated
310 && !parameters->options().relocatable()
311 && !parameters->options().emit_relocs()
312 && !parameters->incremental())
313 continue;
315 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx_)
317 this->error(_("relocation section %u uses unexpected "
318 "symbol table %u"),
319 i, this->adjust_shndx(shdr.get_sh_link()));
320 continue;
323 off_t sh_size = shdr.get_sh_size();
325 if (sh_size == 0)
326 continue;
328 unsigned int reloc_size;
329 if (sh_type == elfcpp::SHT_REL)
330 reloc_size = elfcpp::Elf_sizes<size>::rel_size;
331 else
332 reloc_size = elfcpp::Elf_sizes<size>::rela_size;
333 if (reloc_size != shdr.get_sh_entsize())
335 this->error(_("unexpected entsize for reloc section %u: %lu != %u"),
336 i, static_cast<unsigned long>(shdr.get_sh_entsize()),
337 reloc_size);
338 continue;
341 size_t reloc_count = sh_size / reloc_size;
342 if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
344 this->error(_("reloc section %u size %lu uneven"),
345 i, static_cast<unsigned long>(sh_size));
346 continue;
349 rd->relocs.push_back(Section_relocs());
350 Section_relocs& sr(rd->relocs.back());
351 sr.reloc_shndx = i;
352 sr.data_shndx = shndx;
353 sr.contents = this->get_lasting_view(shdr.get_sh_offset(), sh_size,
354 true, true);
355 sr.sh_type = sh_type;
356 sr.reloc_count = reloc_count;
357 sr.output_section = os;
358 sr.needs_special_offset_handling = out_offsets[shndx] == invalid_address;
359 sr.is_data_section_allocated = is_section_allocated;
362 // Read the local symbols.
363 gold_assert(this->symtab_shndx_ != -1U);
364 if (this->symtab_shndx_ == 0 || this->local_symbol_count_ == 0)
365 rd->local_symbols = NULL;
366 else
368 typename This::Shdr symtabshdr(pshdrs
369 + this->symtab_shndx_ * This::shdr_size);
370 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
371 const int sym_size = This::sym_size;
372 const unsigned int loccount = this->local_symbol_count_;
373 gold_assert(loccount == symtabshdr.get_sh_info());
374 off_t locsize = loccount * sym_size;
375 rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(),
376 locsize, true, true);
380 // Process the relocs to generate mappings from source sections to referenced
381 // sections. This is used during garbage collection to determine garbage
382 // sections.
384 template<int size, bool big_endian>
385 void
386 Sized_relobj_file<size, big_endian>::do_gc_process_relocs(Symbol_table* symtab,
387 Layout* layout,
388 Read_relocs_data* rd)
390 Sized_target<size, big_endian>* target =
391 parameters->sized_target<size, big_endian>();
393 const unsigned char* local_symbols;
394 if (rd->local_symbols == NULL)
395 local_symbols = NULL;
396 else
397 local_symbols = rd->local_symbols->data();
399 for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
400 p != rd->relocs.end();
401 ++p)
403 if (!parameters->options().relocatable())
405 // As noted above, when not generating an object file, we
406 // only scan allocated sections. We may see a non-allocated
407 // section here if we are emitting relocs.
408 if (p->is_data_section_allocated)
409 target->gc_process_relocs(symtab, layout, this,
410 p->data_shndx, p->sh_type,
411 p->contents->data(), p->reloc_count,
412 p->output_section,
413 p->needs_special_offset_handling,
414 this->local_symbol_count_,
415 local_symbols);
421 // Scan the relocs and adjust the symbol table. This looks for
422 // relocations which require GOT/PLT/COPY relocations.
424 template<int size, bool big_endian>
425 void
426 Sized_relobj_file<size, big_endian>::do_scan_relocs(Symbol_table* symtab,
427 Layout* layout,
428 Read_relocs_data* rd)
430 Sized_target<size, big_endian>* target =
431 parameters->sized_target<size, big_endian>();
433 const unsigned char* local_symbols;
434 if (rd->local_symbols == NULL)
435 local_symbols = NULL;
436 else
437 local_symbols = rd->local_symbols->data();
439 // For incremental links, allocate the counters for incremental relocations.
440 if (layout->incremental_inputs() != NULL)
441 this->allocate_incremental_reloc_counts();
443 for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
444 p != rd->relocs.end();
445 ++p)
447 // When garbage collection is on, unreferenced sections are not included
448 // in the link that would have been included normally. This is known only
449 // after Read_relocs hence this check has to be done again.
450 if (parameters->options().gc_sections()
451 || parameters->options().icf_enabled())
453 if (p->output_section == NULL)
454 continue;
456 if (!parameters->options().relocatable())
458 // As noted above, when not generating an object file, we
459 // only scan allocated sections. We may see a non-allocated
460 // section here if we are emitting relocs.
461 if (p->is_data_section_allocated)
462 target->scan_relocs(symtab, layout, this, p->data_shndx,
463 p->sh_type, p->contents->data(),
464 p->reloc_count, p->output_section,
465 p->needs_special_offset_handling,
466 this->local_symbol_count_,
467 local_symbols);
468 if (parameters->options().emit_relocs())
469 this->emit_relocs_scan(symtab, layout, local_symbols, p);
470 if (layout->incremental_inputs() != NULL)
471 this->incremental_relocs_scan(p);
473 else
475 Relocatable_relocs* rr = this->relocatable_relocs(p->reloc_shndx);
476 gold_assert(rr != NULL);
477 rr->set_reloc_count(p->reloc_count);
478 target->scan_relocatable_relocs(symtab, layout, this,
479 p->data_shndx, p->sh_type,
480 p->contents->data(),
481 p->reloc_count,
482 p->output_section,
483 p->needs_special_offset_handling,
484 this->local_symbol_count_,
485 local_symbols,
486 rr);
489 delete p->contents;
490 p->contents = NULL;
493 // For incremental links, finalize the allocation of relocations.
494 if (layout->incremental_inputs() != NULL)
495 this->finalize_incremental_relocs(layout, true);
497 if (rd->local_symbols != NULL)
499 delete rd->local_symbols;
500 rd->local_symbols = NULL;
504 // This is a strategy class we use when scanning for --emit-relocs.
506 template<int sh_type>
507 class Emit_relocs_strategy
509 public:
510 // A local non-section symbol.
511 inline Relocatable_relocs::Reloc_strategy
512 local_non_section_strategy(unsigned int, Relobj*, unsigned int)
513 { return Relocatable_relocs::RELOC_COPY; }
515 // A local section symbol.
516 inline Relocatable_relocs::Reloc_strategy
517 local_section_strategy(unsigned int, Relobj*)
519 if (sh_type == elfcpp::SHT_RELA)
520 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
521 else
523 // The addend is stored in the section contents. Since this
524 // is not a relocatable link, we are going to apply the
525 // relocation contents to the section as usual. This means
526 // that we have no way to record the original addend. If the
527 // original addend is not zero, there is basically no way for
528 // the user to handle this correctly. Caveat emptor.
529 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
533 // A global symbol.
534 inline Relocatable_relocs::Reloc_strategy
535 global_strategy(unsigned int, Relobj*, unsigned int)
536 { return Relocatable_relocs::RELOC_COPY; }
539 // Scan the input relocations for --emit-relocs.
541 template<int size, bool big_endian>
542 void
543 Sized_relobj_file<size, big_endian>::emit_relocs_scan(
544 Symbol_table* symtab,
545 Layout* layout,
546 const unsigned char* plocal_syms,
547 const Read_relocs_data::Relocs_list::iterator& p)
549 Relocatable_relocs* rr = this->relocatable_relocs(p->reloc_shndx);
550 gold_assert(rr != NULL);
551 rr->set_reloc_count(p->reloc_count);
553 if (p->sh_type == elfcpp::SHT_REL)
554 this->emit_relocs_scan_reltype<elfcpp::SHT_REL>(symtab, layout,
555 plocal_syms, p, rr);
556 else
558 gold_assert(p->sh_type == elfcpp::SHT_RELA);
559 this->emit_relocs_scan_reltype<elfcpp::SHT_RELA>(symtab, layout,
560 plocal_syms, p, rr);
564 // Scan the input relocation for --emit-relocs, templatized on the
565 // type of the relocation section.
567 template<int size, bool big_endian>
568 template<int sh_type>
569 void
570 Sized_relobj_file<size, big_endian>::emit_relocs_scan_reltype(
571 Symbol_table* symtab,
572 Layout* layout,
573 const unsigned char* plocal_syms,
574 const Read_relocs_data::Relocs_list::iterator& p,
575 Relocatable_relocs* rr)
577 scan_relocatable_relocs<size, big_endian, sh_type,
578 Emit_relocs_strategy<sh_type> >(
579 symtab,
580 layout,
581 this,
582 p->data_shndx,
583 p->contents->data(),
584 p->reloc_count,
585 p->output_section,
586 p->needs_special_offset_handling,
587 this->local_symbol_count_,
588 plocal_syms,
589 rr);
592 // Scan the input relocations for --incremental.
594 template<int size, bool big_endian>
595 void
596 Sized_relobj_file<size, big_endian>::incremental_relocs_scan(
597 const Read_relocs_data::Relocs_list::iterator& p)
599 if (p->sh_type == elfcpp::SHT_REL)
600 this->incremental_relocs_scan_reltype<elfcpp::SHT_REL>(p);
601 else
603 gold_assert(p->sh_type == elfcpp::SHT_RELA);
604 this->incremental_relocs_scan_reltype<elfcpp::SHT_RELA>(p);
608 // Scan the input relocation for --incremental, templatized on the
609 // type of the relocation section.
611 template<int size, bool big_endian>
612 template<int sh_type>
613 void
614 Sized_relobj_file<size, big_endian>::incremental_relocs_scan_reltype(
615 const Read_relocs_data::Relocs_list::iterator& p)
617 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
618 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
619 const unsigned char* prelocs = p->contents->data();
620 size_t reloc_count = p->reloc_count;
622 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
624 Reltype reloc(prelocs);
626 if (p->needs_special_offset_handling
627 && !p->output_section->is_input_address_mapped(this, p->data_shndx,
628 reloc.get_r_offset()))
629 continue;
631 typename elfcpp::Elf_types<size>::Elf_WXword r_info =
632 reloc.get_r_info();
633 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
635 if (r_sym >= this->local_symbol_count_)
636 this->count_incremental_reloc(r_sym - this->local_symbol_count_);
640 // Relocate the input sections and write out the local symbols.
642 template<int size, bool big_endian>
643 void
644 Sized_relobj_file<size, big_endian>::do_relocate(const Symbol_table* symtab,
645 const Layout* layout,
646 Output_file* of)
648 unsigned int shnum = this->shnum();
650 // Read the section headers.
651 const unsigned char* pshdrs = this->get_view(this->elf_file_.shoff(),
652 shnum * This::shdr_size,
653 true, true);
655 Views views;
656 views.resize(shnum);
658 // Make two passes over the sections. The first one copies the
659 // section data to the output file. The second one applies
660 // relocations.
662 this->write_sections(layout, pshdrs, of, &views);
664 // To speed up relocations, we set up hash tables for fast lookup of
665 // input offsets to output addresses.
666 this->initialize_input_to_output_maps();
668 // Apply relocations.
670 this->relocate_sections(symtab, layout, pshdrs, of, &views);
672 // After we've done the relocations, we release the hash tables,
673 // since we no longer need them.
674 this->free_input_to_output_maps();
676 // Write out the accumulated views.
677 for (unsigned int i = 1; i < shnum; ++i)
679 if (views[i].view != NULL)
681 if (views[i].is_ctors_reverse_view)
682 this->reverse_words(views[i].view, views[i].view_size);
683 if (!views[i].is_postprocessing_view)
685 if (views[i].is_input_output_view)
686 of->write_input_output_view(views[i].offset,
687 views[i].view_size,
688 views[i].view);
689 else
690 of->write_output_view(views[i].offset, views[i].view_size,
691 views[i].view);
696 // Write out the local symbols.
697 this->write_local_symbols(of, layout->sympool(), layout->dynpool(),
698 layout->symtab_xindex(), layout->dynsym_xindex(),
699 layout->symtab_section_offset());
702 // Sort a Read_multiple vector by file offset.
703 struct Read_multiple_compare
705 inline bool
706 operator()(const File_read::Read_multiple_entry& rme1,
707 const File_read::Read_multiple_entry& rme2) const
708 { return rme1.file_offset < rme2.file_offset; }
711 // Write section data to the output file. PSHDRS points to the
712 // section headers. Record the views in *PVIEWS for use when
713 // relocating.
715 template<int size, bool big_endian>
716 void
717 Sized_relobj_file<size, big_endian>::write_sections(const Layout* layout,
718 const unsigned char* pshdrs,
719 Output_file* of,
720 Views* pviews)
722 unsigned int shnum = this->shnum();
723 const Output_sections& out_sections(this->output_sections());
724 const std::vector<Address>& out_offsets(this->section_offsets());
726 File_read::Read_multiple rm;
727 bool is_sorted = true;
729 const unsigned char* p = pshdrs + This::shdr_size;
730 for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
732 View_size* pvs = &(*pviews)[i];
734 pvs->view = NULL;
736 const Output_section* os = out_sections[i];
737 if (os == NULL)
738 continue;
739 Address output_offset = out_offsets[i];
741 typename This::Shdr shdr(p);
743 if (shdr.get_sh_type() == elfcpp::SHT_NOBITS)
744 continue;
746 if ((parameters->options().relocatable()
747 || parameters->options().emit_relocs())
748 && (shdr.get_sh_type() == elfcpp::SHT_REL
749 || shdr.get_sh_type() == elfcpp::SHT_RELA)
750 && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
752 // This is a reloc section in a relocatable link or when
753 // emitting relocs. We don't need to read the input file.
754 // The size and file offset are stored in the
755 // Relocatable_relocs structure.
756 Relocatable_relocs* rr = this->relocatable_relocs(i);
757 gold_assert(rr != NULL);
758 Output_data* posd = rr->output_data();
759 gold_assert(posd != NULL);
761 pvs->offset = posd->offset();
762 pvs->view_size = posd->data_size();
763 pvs->view = of->get_output_view(pvs->offset, pvs->view_size);
764 pvs->address = posd->address();
765 pvs->is_input_output_view = false;
766 pvs->is_postprocessing_view = false;
767 pvs->is_ctors_reverse_view = false;
769 continue;
772 // In the normal case, this input section is simply mapped to
773 // the output section at offset OUTPUT_OFFSET.
775 // However, if OUTPUT_OFFSET == INVALID_ADDRESS, then input data is
776 // handled specially--e.g., a .eh_frame section. The relocation
777 // routines need to check for each reloc where it should be
778 // applied. For this case, we need an input/output view for the
779 // entire contents of the section in the output file. We don't
780 // want to copy the contents of the input section to the output
781 // section; the output section contents were already written,
782 // and we waited for them in Relocate_task::is_runnable because
783 // relocs_must_follow_section_writes is set for the object.
785 // Regardless of which of the above cases is true, we have to
786 // check requires_postprocessing of the output section. If that
787 // is false, then we work with views of the output file
788 // directly. If it is true, then we work with a separate
789 // buffer, and the output section is responsible for writing the
790 // final data to the output file.
792 off_t output_section_offset;
793 Address output_section_size;
794 if (!os->requires_postprocessing())
796 output_section_offset = os->offset();
797 output_section_size = convert_types<Address, off_t>(os->data_size());
799 else
801 output_section_offset = 0;
802 output_section_size =
803 convert_types<Address, off_t>(os->postprocessing_buffer_size());
806 off_t view_start;
807 section_size_type view_size;
808 bool must_decompress = false;
809 if (output_offset != invalid_address)
811 view_start = output_section_offset + output_offset;
812 view_size = convert_to_section_size_type(shdr.get_sh_size());
813 section_size_type uncompressed_size;
814 if (this->section_is_compressed(i, &uncompressed_size))
816 view_size = uncompressed_size;
817 must_decompress = true;
820 else
822 view_start = output_section_offset;
823 view_size = convert_to_section_size_type(output_section_size);
826 if (view_size == 0)
827 continue;
829 gold_assert(output_offset == invalid_address
830 || output_offset + view_size <= output_section_size);
832 unsigned char* view;
833 if (os->requires_postprocessing())
835 unsigned char* buffer = os->postprocessing_buffer();
836 view = buffer + view_start;
837 if (output_offset != invalid_address && !must_decompress)
839 off_t sh_offset = shdr.get_sh_offset();
840 if (!rm.empty() && rm.back().file_offset > sh_offset)
841 is_sorted = false;
842 rm.push_back(File_read::Read_multiple_entry(sh_offset,
843 view_size, view));
846 else
848 if (output_offset == invalid_address)
849 view = of->get_input_output_view(view_start, view_size);
850 else
852 view = of->get_output_view(view_start, view_size);
853 if (!must_decompress)
855 off_t sh_offset = shdr.get_sh_offset();
856 if (!rm.empty() && rm.back().file_offset > sh_offset)
857 is_sorted = false;
858 rm.push_back(File_read::Read_multiple_entry(sh_offset,
859 view_size, view));
864 if (must_decompress)
866 // Read and decompress the section.
867 section_size_type len;
868 const unsigned char* p = this->section_contents(i, &len, false);
869 if (!decompress_input_section(p, len, view, view_size))
870 this->error(_("could not decompress section %s"),
871 this->section_name(i).c_str());
874 pvs->view = view;
875 pvs->address = os->address();
876 if (output_offset != invalid_address)
877 pvs->address += output_offset;
878 pvs->offset = view_start;
879 pvs->view_size = view_size;
880 pvs->is_input_output_view = output_offset == invalid_address;
881 pvs->is_postprocessing_view = os->requires_postprocessing();
882 pvs->is_ctors_reverse_view =
883 (!parameters->options().relocatable()
884 && view_size > size / 8
885 && (strcmp(os->name(), ".init_array") == 0
886 || strcmp(os->name(), ".fini_array") == 0)
887 && layout->is_ctors_in_init_array(this, i));
890 // Actually read the data.
891 if (!rm.empty())
893 if (!is_sorted)
894 std::sort(rm.begin(), rm.end(), Read_multiple_compare());
895 this->read_multiple(rm);
899 // Relocate section data. VIEWS points to the section data as views
900 // in the output file.
902 template<int size, bool big_endian>
903 void
904 Sized_relobj_file<size, big_endian>::do_relocate_sections(
905 const Symbol_table* symtab,
906 const Layout* layout,
907 const unsigned char* pshdrs,
908 Output_file* of,
909 Views* pviews)
911 unsigned int shnum = this->shnum();
912 Sized_target<size, big_endian>* target =
913 parameters->sized_target<size, big_endian>();
915 const Output_sections& out_sections(this->output_sections());
916 const std::vector<Address>& out_offsets(this->section_offsets());
918 Relocate_info<size, big_endian> relinfo;
919 relinfo.symtab = symtab;
920 relinfo.layout = layout;
921 relinfo.object = this;
923 const unsigned char* p = pshdrs + This::shdr_size;
924 for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
926 typename This::Shdr shdr(p);
928 unsigned int sh_type = shdr.get_sh_type();
929 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
930 continue;
932 off_t sh_size = shdr.get_sh_size();
933 if (sh_size == 0)
934 continue;
936 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
937 if (index >= this->shnum())
939 this->error(_("relocation section %u has bad info %u"),
940 i, index);
941 continue;
944 Output_section* os = out_sections[index];
945 if (os == NULL)
947 // This relocation section is against a section which we
948 // discarded.
949 continue;
951 Address output_offset = out_offsets[index];
953 gold_assert((*pviews)[index].view != NULL);
954 if (parameters->options().relocatable())
955 gold_assert((*pviews)[i].view != NULL);
957 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx_)
959 gold_error(_("relocation section %u uses unexpected "
960 "symbol table %u"),
961 i, this->adjust_shndx(shdr.get_sh_link()));
962 continue;
965 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
966 sh_size, true, false);
968 unsigned int reloc_size;
969 if (sh_type == elfcpp::SHT_REL)
970 reloc_size = elfcpp::Elf_sizes<size>::rel_size;
971 else
972 reloc_size = elfcpp::Elf_sizes<size>::rela_size;
974 if (reloc_size != shdr.get_sh_entsize())
976 gold_error(_("unexpected entsize for reloc section %u: %lu != %u"),
977 i, static_cast<unsigned long>(shdr.get_sh_entsize()),
978 reloc_size);
979 continue;
982 size_t reloc_count = sh_size / reloc_size;
983 if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
985 gold_error(_("reloc section %u size %lu uneven"),
986 i, static_cast<unsigned long>(sh_size));
987 continue;
990 gold_assert(output_offset != invalid_address
991 || this->relocs_must_follow_section_writes());
993 relinfo.reloc_shndx = i;
994 relinfo.reloc_shdr = p;
995 relinfo.data_shndx = index;
996 relinfo.data_shdr = pshdrs + index * This::shdr_size;
997 unsigned char* view = (*pviews)[index].view;
998 Address address = (*pviews)[index].address;
999 section_size_type view_size = (*pviews)[index].view_size;
1001 Reloc_symbol_changes* reloc_map = NULL;
1002 if (this->uses_split_stack() && output_offset != invalid_address)
1004 typename This::Shdr data_shdr(pshdrs + index * This::shdr_size);
1005 if ((data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
1006 this->split_stack_adjust(symtab, pshdrs, sh_type, index,
1007 prelocs, reloc_count, view, view_size,
1008 &reloc_map);
1011 if (!parameters->options().relocatable())
1013 target->relocate_section(&relinfo, sh_type, prelocs, reloc_count, os,
1014 output_offset == invalid_address,
1015 view, address, view_size, reloc_map);
1016 if (parameters->options().emit_relocs())
1017 this->emit_relocs(&relinfo, i, sh_type, prelocs, reloc_count,
1018 os, output_offset, view, address, view_size,
1019 (*pviews)[i].view, (*pviews)[i].view_size);
1020 if (parameters->incremental())
1021 this->incremental_relocs_write(&relinfo, sh_type, prelocs,
1022 reloc_count, os, output_offset, of);
1024 else
1026 Relocatable_relocs* rr = this->relocatable_relocs(i);
1027 target->relocate_for_relocatable(&relinfo, sh_type, prelocs,
1028 reloc_count, os, output_offset, rr,
1029 view, address, view_size,
1030 (*pviews)[i].view,
1031 (*pviews)[i].view_size);
1036 // Emit the relocs for --emit-relocs.
1038 template<int size, bool big_endian>
1039 void
1040 Sized_relobj_file<size, big_endian>::emit_relocs(
1041 const Relocate_info<size, big_endian>* relinfo,
1042 unsigned int i,
1043 unsigned int sh_type,
1044 const unsigned char* prelocs,
1045 size_t reloc_count,
1046 Output_section* output_section,
1047 typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
1048 unsigned char* view,
1049 typename elfcpp::Elf_types<size>::Elf_Addr address,
1050 section_size_type view_size,
1051 unsigned char* reloc_view,
1052 section_size_type reloc_view_size)
1054 if (sh_type == elfcpp::SHT_REL)
1055 this->emit_relocs_reltype<elfcpp::SHT_REL>(relinfo, i, prelocs,
1056 reloc_count, output_section,
1057 offset_in_output_section,
1058 view, address, view_size,
1059 reloc_view, reloc_view_size);
1060 else
1062 gold_assert(sh_type == elfcpp::SHT_RELA);
1063 this->emit_relocs_reltype<elfcpp::SHT_RELA>(relinfo, i, prelocs,
1064 reloc_count, output_section,
1065 offset_in_output_section,
1066 view, address, view_size,
1067 reloc_view, reloc_view_size);
1071 // Emit the relocs for --emit-relocs, templatized on the type of the
1072 // relocation section.
1074 template<int size, bool big_endian>
1075 template<int sh_type>
1076 void
1077 Sized_relobj_file<size, big_endian>::emit_relocs_reltype(
1078 const Relocate_info<size, big_endian>* relinfo,
1079 unsigned int i,
1080 const unsigned char* prelocs,
1081 size_t reloc_count,
1082 Output_section* output_section,
1083 typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
1084 unsigned char* view,
1085 typename elfcpp::Elf_types<size>::Elf_Addr address,
1086 section_size_type view_size,
1087 unsigned char* reloc_view,
1088 section_size_type reloc_view_size)
1090 const Relocatable_relocs* rr = this->relocatable_relocs(i);
1091 relocate_for_relocatable<size, big_endian, sh_type>(
1092 relinfo,
1093 prelocs,
1094 reloc_count,
1095 output_section,
1096 offset_in_output_section,
1098 view,
1099 address,
1100 view_size,
1101 reloc_view,
1102 reloc_view_size);
1105 // Write the incremental relocs.
1107 template<int size, bool big_endian>
1108 void
1109 Sized_relobj_file<size, big_endian>::incremental_relocs_write(
1110 const Relocate_info<size, big_endian>* relinfo,
1111 unsigned int sh_type,
1112 const unsigned char* prelocs,
1113 size_t reloc_count,
1114 Output_section* output_section,
1115 Address output_offset,
1116 Output_file* of)
1118 if (sh_type == elfcpp::SHT_REL)
1119 this->incremental_relocs_write_reltype<elfcpp::SHT_REL>(
1120 relinfo,
1121 prelocs,
1122 reloc_count,
1123 output_section,
1124 output_offset,
1125 of);
1126 else
1128 gold_assert(sh_type == elfcpp::SHT_RELA);
1129 this->incremental_relocs_write_reltype<elfcpp::SHT_RELA>(
1130 relinfo,
1131 prelocs,
1132 reloc_count,
1133 output_section,
1134 output_offset,
1135 of);
1139 // Write the incremental relocs, templatized on the type of the
1140 // relocation section.
1142 template<int size, bool big_endian>
1143 template<int sh_type>
1144 void
1145 Sized_relobj_file<size, big_endian>::incremental_relocs_write_reltype(
1146 const Relocate_info<size, big_endian>* relinfo,
1147 const unsigned char* prelocs,
1148 size_t reloc_count,
1149 Output_section* output_section,
1150 Address output_offset,
1151 Output_file* of)
1153 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reloc;
1154 const unsigned int reloc_size =
1155 Reloc_types<sh_type, size, big_endian>::reloc_size;
1156 const unsigned int sizeof_addr = size / 8;
1157 const unsigned int incr_reloc_size =
1158 Incremental_relocs_reader<size, big_endian>::reloc_size;
1160 unsigned int out_shndx = output_section->out_shndx();
1162 // Get a view for the .gnu_incremental_relocs section.
1164 Incremental_inputs* inputs = relinfo->layout->incremental_inputs();
1165 gold_assert(inputs != NULL);
1166 const off_t relocs_off = inputs->relocs_section()->offset();
1167 const off_t relocs_size = inputs->relocs_section()->data_size();
1168 unsigned char* const view = of->get_output_view(relocs_off, relocs_size);
1170 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
1172 Reloc reloc(prelocs);
1174 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
1175 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
1176 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
1178 if (r_sym < this->local_symbol_count_)
1179 continue;
1181 // Get the new offset--the location in the output section where
1182 // this relocation should be applied.
1184 Address offset = reloc.get_r_offset();
1185 if (output_offset != invalid_address)
1186 offset += output_offset;
1187 else
1189 section_offset_type sot_offset =
1190 convert_types<section_offset_type, Address>(offset);
1191 section_offset_type new_sot_offset =
1192 output_section->output_offset(relinfo->object,
1193 relinfo->data_shndx,
1194 sot_offset);
1195 gold_assert(new_sot_offset != -1);
1196 offset += new_sot_offset;
1199 // Get the addend.
1200 typename elfcpp::Elf_types<size>::Elf_Swxword addend;
1201 if (sh_type == elfcpp::SHT_RELA)
1202 addend =
1203 Reloc_types<sh_type, size, big_endian>::get_reloc_addend(&reloc);
1204 else
1206 // FIXME: Get the addend for SHT_REL.
1207 addend = 0;
1210 // Get the index of the output relocation.
1212 unsigned int reloc_index =
1213 this->next_incremental_reloc_index(r_sym - this->local_symbol_count_);
1215 // Write the relocation.
1217 unsigned char* pov = view + reloc_index * incr_reloc_size;
1218 elfcpp::Swap<32, big_endian>::writeval(pov, r_type);
1219 elfcpp::Swap<32, big_endian>::writeval(pov + 4, out_shndx);
1220 elfcpp::Swap<size, big_endian>::writeval(pov + 8, offset);
1221 elfcpp::Swap<size, big_endian>::writeval(pov + 8 + sizeof_addr, addend);
1222 of->write_output_view(pov - view, incr_reloc_size, view);
1226 // Create merge hash tables for the local symbols. These are used to
1227 // speed up relocations.
1229 template<int size, bool big_endian>
1230 void
1231 Sized_relobj_file<size, big_endian>::initialize_input_to_output_maps()
1233 const unsigned int loccount = this->local_symbol_count_;
1234 for (unsigned int i = 1; i < loccount; ++i)
1236 Symbol_value<size>& lv(this->local_values_[i]);
1237 lv.initialize_input_to_output_map(this);
1241 // Free merge hash tables for the local symbols.
1243 template<int size, bool big_endian>
1244 void
1245 Sized_relobj_file<size, big_endian>::free_input_to_output_maps()
1247 const unsigned int loccount = this->local_symbol_count_;
1248 for (unsigned int i = 1; i < loccount; ++i)
1250 Symbol_value<size>& lv(this->local_values_[i]);
1251 lv.free_input_to_output_map();
1255 // If an object was compiled with -fsplit-stack, this is called to
1256 // check whether any relocations refer to functions defined in objects
1257 // which were not compiled with -fsplit-stack. If they were, then we
1258 // need to apply some target-specific adjustments to request
1259 // additional stack space.
1261 template<int size, bool big_endian>
1262 void
1263 Sized_relobj_file<size, big_endian>::split_stack_adjust(
1264 const Symbol_table* symtab,
1265 const unsigned char* pshdrs,
1266 unsigned int sh_type,
1267 unsigned int shndx,
1268 const unsigned char* prelocs,
1269 size_t reloc_count,
1270 unsigned char* view,
1271 section_size_type view_size,
1272 Reloc_symbol_changes** reloc_map)
1274 if (sh_type == elfcpp::SHT_REL)
1275 this->split_stack_adjust_reltype<elfcpp::SHT_REL>(symtab, pshdrs, shndx,
1276 prelocs, reloc_count,
1277 view, view_size,
1278 reloc_map);
1279 else
1281 gold_assert(sh_type == elfcpp::SHT_RELA);
1282 this->split_stack_adjust_reltype<elfcpp::SHT_RELA>(symtab, pshdrs, shndx,
1283 prelocs, reloc_count,
1284 view, view_size,
1285 reloc_map);
1289 // Adjust for -fsplit-stack, templatized on the type of the relocation
1290 // section.
1292 template<int size, bool big_endian>
1293 template<int sh_type>
1294 void
1295 Sized_relobj_file<size, big_endian>::split_stack_adjust_reltype(
1296 const Symbol_table* symtab,
1297 const unsigned char* pshdrs,
1298 unsigned int shndx,
1299 const unsigned char* prelocs,
1300 size_t reloc_count,
1301 unsigned char* view,
1302 section_size_type view_size,
1303 Reloc_symbol_changes** reloc_map)
1305 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
1306 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
1308 size_t local_count = this->local_symbol_count();
1310 std::vector<section_offset_type> non_split_refs;
1312 const unsigned char* pr = prelocs;
1313 for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
1315 Reltype reloc(pr);
1317 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
1318 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
1319 if (r_sym < local_count)
1320 continue;
1322 const Symbol* gsym = this->global_symbol(r_sym);
1323 gold_assert(gsym != NULL);
1324 if (gsym->is_forwarder())
1325 gsym = symtab->resolve_forwards(gsym);
1327 // See if this relocation refers to a function defined in an
1328 // object compiled without -fsplit-stack. Note that we don't
1329 // care about the type of relocation--this means that in some
1330 // cases we will ask for a large stack unnecessarily, but this
1331 // is not fatal. FIXME: Some targets have symbols which are
1332 // functions but are not type STT_FUNC, e.g., STT_ARM_TFUNC.
1333 if (!gsym->is_undefined()
1334 && gsym->source() == Symbol::FROM_OBJECT
1335 && !gsym->object()->uses_split_stack())
1337 unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
1338 if (parameters->target().is_call_to_non_split(gsym, r_type))
1340 section_offset_type offset =
1341 convert_to_section_size_type(reloc.get_r_offset());
1342 non_split_refs.push_back(offset);
1347 if (non_split_refs.empty())
1348 return;
1350 // At this point, every entry in NON_SPLIT_REFS indicates a
1351 // relocation which refers to a function in an object compiled
1352 // without -fsplit-stack. We now have to convert that list into a
1353 // set of offsets to functions. First, we find all the functions.
1355 Function_offsets function_offsets;
1356 this->find_functions(pshdrs, shndx, &function_offsets);
1357 if (function_offsets.empty())
1358 return;
1360 // Now get a list of the function with references to non split-stack
1361 // code.
1363 Function_offsets calls_non_split;
1364 for (std::vector<section_offset_type>::const_iterator p
1365 = non_split_refs.begin();
1366 p != non_split_refs.end();
1367 ++p)
1369 Function_offsets::const_iterator low = function_offsets.lower_bound(*p);
1370 if (low == function_offsets.end())
1371 --low;
1372 else if (low->first == *p)
1374 else if (low == function_offsets.begin())
1375 continue;
1376 else
1377 --low;
1379 calls_non_split.insert(*low);
1381 if (calls_non_split.empty())
1382 return;
1384 // Now we have a set of functions to adjust. The adjustments are
1385 // target specific. Besides changing the output section view
1386 // however, it likes, the target may request a relocation change
1387 // from one global symbol name to another.
1389 for (Function_offsets::const_iterator p = calls_non_split.begin();
1390 p != calls_non_split.end();
1391 ++p)
1393 std::string from;
1394 std::string to;
1395 parameters->target().calls_non_split(this, shndx, p->first, p->second,
1396 view, view_size, &from, &to);
1397 if (!from.empty())
1399 gold_assert(!to.empty());
1400 Symbol* tosym = NULL;
1402 // Find relocations in the relevant function which are for
1403 // FROM.
1404 pr = prelocs;
1405 for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
1407 Reltype reloc(pr);
1409 typename elfcpp::Elf_types<size>::Elf_WXword r_info =
1410 reloc.get_r_info();
1411 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
1412 if (r_sym < local_count)
1413 continue;
1415 section_offset_type offset =
1416 convert_to_section_size_type(reloc.get_r_offset());
1417 if (offset < p->first
1418 || (offset
1419 >= (p->first
1420 + static_cast<section_offset_type>(p->second))))
1421 continue;
1423 const Symbol* gsym = this->global_symbol(r_sym);
1424 if (from == gsym->name())
1426 if (tosym == NULL)
1428 tosym = symtab->lookup(to.c_str());
1429 if (tosym == NULL)
1431 this->error(_("could not convert call "
1432 "to '%s' to '%s'"),
1433 from.c_str(), to.c_str());
1434 break;
1438 if (*reloc_map == NULL)
1439 *reloc_map = new Reloc_symbol_changes(reloc_count);
1440 (*reloc_map)->set(i, tosym);
1447 // Find all the function in this object defined in section SHNDX.
1448 // Store their offsets in the section in FUNCTION_OFFSETS.
1450 template<int size, bool big_endian>
1451 void
1452 Sized_relobj_file<size, big_endian>::find_functions(
1453 const unsigned char* pshdrs,
1454 unsigned int shndx,
1455 Sized_relobj_file<size, big_endian>::Function_offsets* function_offsets)
1457 // We need to read the symbols to find the functions. If we wanted
1458 // to, we could cache reading the symbols across all sections in the
1459 // object.
1460 const unsigned int symtab_shndx = this->symtab_shndx_;
1461 typename This::Shdr symtabshdr(pshdrs + symtab_shndx * This::shdr_size);
1462 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
1464 typename elfcpp::Elf_types<size>::Elf_WXword sh_size =
1465 symtabshdr.get_sh_size();
1466 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
1467 sh_size, true, true);
1469 const int sym_size = This::sym_size;
1470 const unsigned int symcount = sh_size / sym_size;
1471 for (unsigned int i = 0; i < symcount; ++i, psyms += sym_size)
1473 typename elfcpp::Sym<size, big_endian> isym(psyms);
1475 // FIXME: Some targets can have functions which do not have type
1476 // STT_FUNC, e.g., STT_ARM_TFUNC.
1477 if (isym.get_st_type() != elfcpp::STT_FUNC
1478 || isym.get_st_size() == 0)
1479 continue;
1481 bool is_ordinary;
1482 unsigned int sym_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(),
1483 &is_ordinary);
1484 if (!is_ordinary || sym_shndx != shndx)
1485 continue;
1487 section_offset_type value =
1488 convert_to_section_size_type(isym.get_st_value());
1489 section_size_type fnsize =
1490 convert_to_section_size_type(isym.get_st_size());
1492 (*function_offsets)[value] = fnsize;
1496 // Reverse the words in a section. Used for .ctors sections mapped to
1497 // .init_array sections. See ctors_sections_in_init_array in
1498 // layout.cc.
1500 template<int size, bool big_endian>
1501 void
1502 Sized_relobj_file<size, big_endian>::reverse_words(unsigned char* view,
1503 section_size_type view_size)
1505 typedef typename elfcpp::Swap<size, big_endian>::Valtype Valtype;
1506 Valtype* vview = reinterpret_cast<Valtype*>(view);
1507 section_size_type vview_size = view_size / (size / 8);
1508 for (section_size_type i = 0; i < vview_size / 2; ++i)
1510 Valtype tmp = vview[i];
1511 vview[i] = vview[vview_size - 1 - i];
1512 vview[vview_size - 1 - i] = tmp;
1516 // Class Merged_symbol_value.
1518 template<int size>
1519 void
1520 Merged_symbol_value<size>::initialize_input_to_output_map(
1521 const Relobj* object,
1522 unsigned int input_shndx)
1524 Object_merge_map* map = object->merge_map();
1525 map->initialize_input_to_output_map<size>(input_shndx,
1526 this->output_start_address_,
1527 &this->output_addresses_);
1530 // Get the output value corresponding to an input offset if we
1531 // couldn't find it in the hash table.
1533 template<int size>
1534 typename elfcpp::Elf_types<size>::Elf_Addr
1535 Merged_symbol_value<size>::value_from_output_section(
1536 const Relobj* object,
1537 unsigned int input_shndx,
1538 typename elfcpp::Elf_types<size>::Elf_Addr input_offset) const
1540 section_offset_type output_offset;
1541 bool found = object->merge_map()->get_output_offset(NULL, input_shndx,
1542 input_offset,
1543 &output_offset);
1545 // If this assertion fails, it means that some relocation was
1546 // against a portion of an input merge section which we didn't map
1547 // to the output file and we didn't explicitly discard. We should
1548 // always map all portions of input merge sections.
1549 gold_assert(found);
1551 if (output_offset == -1)
1552 return 0;
1553 else
1554 return this->output_start_address_ + output_offset;
1557 // Track_relocs methods.
1559 // Initialize the class to track the relocs. This gets the object,
1560 // the reloc section index, and the type of the relocs. This returns
1561 // false if something goes wrong.
1563 template<int size, bool big_endian>
1564 bool
1565 Track_relocs<size, big_endian>::initialize(
1566 Object* object,
1567 unsigned int reloc_shndx,
1568 unsigned int reloc_type)
1570 // If RELOC_SHNDX is -1U, it means there is more than one reloc
1571 // section for the .eh_frame section. We can't handle that case.
1572 if (reloc_shndx == -1U)
1573 return false;
1575 // If RELOC_SHNDX is 0, there is no reloc section.
1576 if (reloc_shndx == 0)
1577 return true;
1579 // Get the contents of the reloc section.
1580 this->prelocs_ = object->section_contents(reloc_shndx, &this->len_, false);
1582 if (reloc_type == elfcpp::SHT_REL)
1583 this->reloc_size_ = elfcpp::Elf_sizes<size>::rel_size;
1584 else if (reloc_type == elfcpp::SHT_RELA)
1585 this->reloc_size_ = elfcpp::Elf_sizes<size>::rela_size;
1586 else
1587 gold_unreachable();
1589 if (this->len_ % this->reloc_size_ != 0)
1591 object->error(_("reloc section size %zu is not a multiple of "
1592 "reloc size %d\n"),
1593 static_cast<size_t>(this->len_),
1594 this->reloc_size_);
1595 return false;
1598 return true;
1601 // Return the offset of the next reloc, or -1 if there isn't one.
1603 template<int size, bool big_endian>
1604 off_t
1605 Track_relocs<size, big_endian>::next_offset() const
1607 if (this->pos_ >= this->len_)
1608 return -1;
1610 // Rel and Rela start out the same, so we can always use Rel to find
1611 // the r_offset value.
1612 elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
1613 return rel.get_r_offset();
1616 // Return the index of the symbol referenced by the next reloc, or -1U
1617 // if there aren't any more relocs.
1619 template<int size, bool big_endian>
1620 unsigned int
1621 Track_relocs<size, big_endian>::next_symndx() const
1623 if (this->pos_ >= this->len_)
1624 return -1U;
1626 // Rel and Rela start out the same, so we can use Rel to find the
1627 // symbol index.
1628 elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
1629 return elfcpp::elf_r_sym<size>(rel.get_r_info());
1632 // Return the addend of the next reloc, or 0 if there isn't one.
1634 template<int size, bool big_endian>
1635 uint64_t
1636 Track_relocs<size, big_endian>::next_addend() const
1638 if (this->pos_ >= this->len_)
1639 return 0;
1640 if (this->reloc_size_ == elfcpp::Elf_sizes<size>::rel_size)
1641 return 0;
1642 elfcpp::Rela<size, big_endian> rela(this->prelocs_ + this->pos_);
1643 return rela.get_r_addend();
1646 // Advance to the next reloc whose r_offset is greater than or equal
1647 // to OFFSET. Return the number of relocs we skip.
1649 template<int size, bool big_endian>
1651 Track_relocs<size, big_endian>::advance(off_t offset)
1653 int ret = 0;
1654 while (this->pos_ < this->len_)
1656 // Rel and Rela start out the same, so we can always use Rel to
1657 // find the r_offset value.
1658 elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
1659 if (static_cast<off_t>(rel.get_r_offset()) >= offset)
1660 break;
1661 ++ret;
1662 this->pos_ += this->reloc_size_;
1664 return ret;
1667 // Instantiate the templates we need.
1669 #ifdef HAVE_TARGET_32_LITTLE
1670 template
1671 void
1672 Sized_relobj_file<32, false>::do_read_relocs(Read_relocs_data* rd);
1673 #endif
1675 #ifdef HAVE_TARGET_32_BIG
1676 template
1677 void
1678 Sized_relobj_file<32, true>::do_read_relocs(Read_relocs_data* rd);
1679 #endif
1681 #ifdef HAVE_TARGET_64_LITTLE
1682 template
1683 void
1684 Sized_relobj_file<64, false>::do_read_relocs(Read_relocs_data* rd);
1685 #endif
1687 #ifdef HAVE_TARGET_64_BIG
1688 template
1689 void
1690 Sized_relobj_file<64, true>::do_read_relocs(Read_relocs_data* rd);
1691 #endif
1693 #ifdef HAVE_TARGET_32_LITTLE
1694 template
1695 void
1696 Sized_relobj_file<32, false>::do_gc_process_relocs(Symbol_table* symtab,
1697 Layout* layout,
1698 Read_relocs_data* rd);
1699 #endif
1701 #ifdef HAVE_TARGET_32_BIG
1702 template
1703 void
1704 Sized_relobj_file<32, true>::do_gc_process_relocs(Symbol_table* symtab,
1705 Layout* layout,
1706 Read_relocs_data* rd);
1707 #endif
1709 #ifdef HAVE_TARGET_64_LITTLE
1710 template
1711 void
1712 Sized_relobj_file<64, false>::do_gc_process_relocs(Symbol_table* symtab,
1713 Layout* layout,
1714 Read_relocs_data* rd);
1715 #endif
1717 #ifdef HAVE_TARGET_64_BIG
1718 template
1719 void
1720 Sized_relobj_file<64, true>::do_gc_process_relocs(Symbol_table* symtab,
1721 Layout* layout,
1722 Read_relocs_data* rd);
1723 #endif
1725 #ifdef HAVE_TARGET_32_LITTLE
1726 template
1727 void
1728 Sized_relobj_file<32, false>::do_scan_relocs(Symbol_table* symtab,
1729 Layout* layout,
1730 Read_relocs_data* rd);
1731 #endif
1733 #ifdef HAVE_TARGET_32_BIG
1734 template
1735 void
1736 Sized_relobj_file<32, true>::do_scan_relocs(Symbol_table* symtab,
1737 Layout* layout,
1738 Read_relocs_data* rd);
1739 #endif
1741 #ifdef HAVE_TARGET_64_LITTLE
1742 template
1743 void
1744 Sized_relobj_file<64, false>::do_scan_relocs(Symbol_table* symtab,
1745 Layout* layout,
1746 Read_relocs_data* rd);
1747 #endif
1749 #ifdef HAVE_TARGET_64_BIG
1750 template
1751 void
1752 Sized_relobj_file<64, true>::do_scan_relocs(Symbol_table* symtab,
1753 Layout* layout,
1754 Read_relocs_data* rd);
1755 #endif
1757 #ifdef HAVE_TARGET_32_LITTLE
1758 template
1759 void
1760 Sized_relobj_file<32, false>::do_relocate(const Symbol_table* symtab,
1761 const Layout* layout,
1762 Output_file* of);
1763 #endif
1765 #ifdef HAVE_TARGET_32_BIG
1766 template
1767 void
1768 Sized_relobj_file<32, true>::do_relocate(const Symbol_table* symtab,
1769 const Layout* layout,
1770 Output_file* of);
1771 #endif
1773 #ifdef HAVE_TARGET_64_LITTLE
1774 template
1775 void
1776 Sized_relobj_file<64, false>::do_relocate(const Symbol_table* symtab,
1777 const Layout* layout,
1778 Output_file* of);
1779 #endif
1781 #ifdef HAVE_TARGET_64_BIG
1782 template
1783 void
1784 Sized_relobj_file<64, true>::do_relocate(const Symbol_table* symtab,
1785 const Layout* layout,
1786 Output_file* of);
1787 #endif
1789 #ifdef HAVE_TARGET_32_LITTLE
1790 template
1791 void
1792 Sized_relobj_file<32, false>::do_relocate_sections(
1793 const Symbol_table* symtab,
1794 const Layout* layout,
1795 const unsigned char* pshdrs,
1796 Output_file* of,
1797 Views* pviews);
1798 #endif
1800 #ifdef HAVE_TARGET_32_BIG
1801 template
1802 void
1803 Sized_relobj_file<32, true>::do_relocate_sections(
1804 const Symbol_table* symtab,
1805 const Layout* layout,
1806 const unsigned char* pshdrs,
1807 Output_file* of,
1808 Views* pviews);
1809 #endif
1811 #ifdef HAVE_TARGET_64_LITTLE
1812 template
1813 void
1814 Sized_relobj_file<64, false>::do_relocate_sections(
1815 const Symbol_table* symtab,
1816 const Layout* layout,
1817 const unsigned char* pshdrs,
1818 Output_file* of,
1819 Views* pviews);
1820 #endif
1822 #ifdef HAVE_TARGET_64_BIG
1823 template
1824 void
1825 Sized_relobj_file<64, true>::do_relocate_sections(
1826 const Symbol_table* symtab,
1827 const Layout* layout,
1828 const unsigned char* pshdrs,
1829 Output_file* of,
1830 Views* pviews);
1831 #endif
1833 #ifdef HAVE_TARGET_32_LITTLE
1834 template
1835 void
1836 Sized_relobj_file<32, false>::initialize_input_to_output_maps();
1838 template
1839 void
1840 Sized_relobj_file<32, false>::free_input_to_output_maps();
1841 #endif
1843 #ifdef HAVE_TARGET_32_BIG
1844 template
1845 void
1846 Sized_relobj_file<32, true>::initialize_input_to_output_maps();
1848 template
1849 void
1850 Sized_relobj_file<32, true>::free_input_to_output_maps();
1851 #endif
1853 #ifdef HAVE_TARGET_64_LITTLE
1854 template
1855 void
1856 Sized_relobj_file<64, false>::initialize_input_to_output_maps();
1858 template
1859 void
1860 Sized_relobj_file<64, false>::free_input_to_output_maps();
1861 #endif
1863 #ifdef HAVE_TARGET_64_BIG
1864 template
1865 void
1866 Sized_relobj_file<64, true>::initialize_input_to_output_maps();
1868 template
1869 void
1870 Sized_relobj_file<64, true>::free_input_to_output_maps();
1871 #endif
1873 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1874 template
1875 class Merged_symbol_value<32>;
1876 #endif
1878 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1879 template
1880 class Merged_symbol_value<64>;
1881 #endif
1883 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1884 template
1885 class Symbol_value<32>;
1886 #endif
1888 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1889 template
1890 class Symbol_value<64>;
1891 #endif
1893 #ifdef HAVE_TARGET_32_LITTLE
1894 template
1895 class Track_relocs<32, false>;
1896 #endif
1898 #ifdef HAVE_TARGET_32_BIG
1899 template
1900 class Track_relocs<32, true>;
1901 #endif
1903 #ifdef HAVE_TARGET_64_LITTLE
1904 template
1905 class Track_relocs<64, false>;
1906 #endif
1908 #ifdef HAVE_TARGET_64_BIG
1909 template
1910 class Track_relocs<64, true>;
1911 #endif
1913 } // End namespace gold.