1 // layout.cc -- lay out output file sections for gold
17 // Layout_task_runner methods.
19 // Lay out the sections. This is called after all the input objects
23 Layout_task_runner::run(Workqueue
* workqueue
)
25 off_t file_size
= this->layout_
->finalize(this->input_objects_
,
28 // Now we know the final size of the output file and we know where
29 // each piece of information goes.
30 Output_file
* of
= new Output_file(this->options_
);
33 // Queue up the final set of tasks.
34 gold::queue_final_tasks(this->options_
, this->input_objects_
,
35 this->symtab_
, this->layout_
, workqueue
, of
);
40 Layout::Layout(const General_options
& options
)
41 : options_(options
), namepool_(), sympool_(), signatures_(),
42 section_name_map_(), segment_list_(), section_list_(),
43 special_output_list_(), tls_segment_(NULL
)
45 // Make space for more than enough segments for a typical file.
46 // This is just for efficiency--it's OK if we wind up needing more.
47 segment_list_
.reserve(12);
50 // Hash a key we use to look up an output section mapping.
53 Layout::Hash_key::operator()(const Layout::Key
& k
) const
55 return reinterpret_cast<size_t>(k
.first
) + k
.second
.first
+ k
.second
.second
;
58 // Whether to include this section in the link.
60 template<int size
, bool big_endian
>
62 Layout::include_section(Object
*, const char*,
63 const elfcpp::Shdr
<size
, big_endian
>& shdr
)
65 // Some section types are never linked. Some are only linked when
66 // doing a relocateable link.
67 switch (shdr
.get_sh_type())
69 case elfcpp::SHT_NULL
:
70 case elfcpp::SHT_SYMTAB
:
71 case elfcpp::SHT_DYNSYM
:
72 case elfcpp::SHT_STRTAB
:
73 case elfcpp::SHT_HASH
:
74 case elfcpp::SHT_DYNAMIC
:
75 case elfcpp::SHT_SYMTAB_SHNDX
:
78 case elfcpp::SHT_RELA
:
80 case elfcpp::SHT_GROUP
:
81 return this->options_
.is_relocatable();
84 // FIXME: Handle stripping debug sections here.
89 // Return an output section named NAME, or NULL if there is none.
92 Layout::find_output_section(const char* name
) const
94 for (Section_name_map::const_iterator p
= this->section_name_map_
.begin();
95 p
!= this->section_name_map_
.end();
97 if (strcmp(p
->first
.first
, name
) == 0)
102 // Return an output segment of type TYPE, with segment flags SET set
103 // and segment flags CLEAR clear. Return NULL if there is none.
106 Layout::find_output_segment(elfcpp::PT type
, elfcpp::Elf_Word set
,
107 elfcpp::Elf_Word clear
) const
109 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
110 p
!= this->segment_list_
.end();
112 if (static_cast<elfcpp::PT
>((*p
)->type()) == type
113 && ((*p
)->flags() & set
) == set
114 && ((*p
)->flags() & clear
) == 0)
119 // Return the output section to use for section NAME with type TYPE
120 // and section flags FLAGS.
123 Layout::get_output_section(const char* name
, elfcpp::Elf_Word type
,
124 elfcpp::Elf_Xword flags
)
126 // We should ignore some flags.
127 flags
&= ~ (elfcpp::SHF_INFO_LINK
128 | elfcpp::SHF_LINK_ORDER
129 | elfcpp::SHF_GROUP
);
131 const Key
key(name
, std::make_pair(type
, flags
));
132 const std::pair
<Key
, Output_section
*> v(key
, NULL
);
133 std::pair
<Section_name_map::iterator
, bool> ins(
134 this->section_name_map_
.insert(v
));
137 return ins
.first
->second
;
140 // This is the first time we've seen this name/type/flags
142 Output_section
* os
= this->make_output_section(name
, type
, flags
);
143 ins
.first
->second
= os
;
148 // Return the output section to use for input section SHNDX, with name
149 // NAME, with header HEADER, from object OBJECT. Set *OFF to the
150 // offset of this input section without the output section.
152 template<int size
, bool big_endian
>
154 Layout::layout(Object
* object
, unsigned int shndx
, const char* name
,
155 const elfcpp::Shdr
<size
, big_endian
>& shdr
, off_t
* off
)
157 if (!this->include_section(object
, name
, shdr
))
160 // If we are not doing a relocateable link, choose the name to use
161 // for the output section.
162 size_t len
= strlen(name
);
163 if (!this->options_
.is_relocatable())
164 name
= Layout::output_section_name(name
, &len
);
166 // FIXME: Handle SHF_OS_NONCONFORMING here.
168 // Canonicalize the section name.
169 name
= this->namepool_
.add(name
, len
);
171 // Find the output section. The output section is selected based on
172 // the section name, type, and flags.
173 Output_section
* os
= this->get_output_section(name
, shdr
.get_sh_type(),
174 shdr
.get_sh_flags());
176 // FIXME: Handle SHF_LINK_ORDER somewhere.
178 *off
= os
->add_input_section(object
, shndx
, name
, shdr
);
183 // Add POSD to an output section using NAME, TYPE, and FLAGS.
186 Layout::add_output_section_data(const char* name
, elfcpp::Elf_Word type
,
187 elfcpp::Elf_Xword flags
,
188 Output_section_data
* posd
)
190 // Canonicalize the name.
191 name
= this->namepool_
.add(name
);
193 Output_section
* os
= this->get_output_section(name
, type
, flags
);
194 os
->add_output_section_data(posd
);
197 // Map section flags to segment flags.
200 Layout::section_flags_to_segment(elfcpp::Elf_Xword flags
)
202 elfcpp::Elf_Word ret
= elfcpp::PF_R
;
203 if ((flags
& elfcpp::SHF_WRITE
) != 0)
205 if ((flags
& elfcpp::SHF_EXECINSTR
) != 0)
210 // Make a new Output_section, and attach it to segments as
214 Layout::make_output_section(const char* name
, elfcpp::Elf_Word type
,
215 elfcpp::Elf_Xword flags
)
217 Output_section
* os
= new Output_section(name
, type
, flags
, true);
219 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
220 this->section_list_
.push_back(os
);
223 // This output section goes into a PT_LOAD segment.
225 elfcpp::Elf_Word seg_flags
= Layout::section_flags_to_segment(flags
);
227 // The only thing we really care about for PT_LOAD segments is
228 // whether or not they are writable, so that is how we search
229 // for them. People who need segments sorted on some other
230 // basis will have to wait until we implement a mechanism for
231 // them to describe the segments they want.
233 Segment_list::const_iterator p
;
234 for (p
= this->segment_list_
.begin();
235 p
!= this->segment_list_
.end();
238 if ((*p
)->type() == elfcpp::PT_LOAD
239 && ((*p
)->flags() & elfcpp::PF_W
) == (seg_flags
& elfcpp::PF_W
))
241 (*p
)->add_output_section(os
, seg_flags
);
246 if (p
== this->segment_list_
.end())
248 Output_segment
* oseg
= new Output_segment(elfcpp::PT_LOAD
,
250 this->segment_list_
.push_back(oseg
);
251 oseg
->add_output_section(os
, seg_flags
);
254 // If we see a loadable SHT_NOTE section, we create a PT_NOTE
256 if (type
== elfcpp::SHT_NOTE
)
258 // See if we already have an equivalent PT_NOTE segment.
259 for (p
= this->segment_list_
.begin();
260 p
!= segment_list_
.end();
263 if ((*p
)->type() == elfcpp::PT_NOTE
264 && (((*p
)->flags() & elfcpp::PF_W
)
265 == (seg_flags
& elfcpp::PF_W
)))
267 (*p
)->add_output_section(os
, seg_flags
);
272 if (p
== this->segment_list_
.end())
274 Output_segment
* oseg
= new Output_segment(elfcpp::PT_NOTE
,
276 this->segment_list_
.push_back(oseg
);
277 oseg
->add_output_section(os
, seg_flags
);
281 // If we see a loadable SHF_TLS section, we create a PT_TLS
282 // segment. There can only be one such segment.
283 if ((flags
& elfcpp::SHF_TLS
) != 0)
285 if (this->tls_segment_
== NULL
)
287 this->tls_segment_
= new Output_segment(elfcpp::PT_TLS
,
289 this->segment_list_
.push_back(this->tls_segment_
);
291 this->tls_segment_
->add_output_section(os
, seg_flags
);
298 // Find the first read-only PT_LOAD segment, creating one if
302 Layout::find_first_load_seg()
304 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
305 p
!= this->segment_list_
.end();
308 if ((*p
)->type() == elfcpp::PT_LOAD
309 && ((*p
)->flags() & elfcpp::PF_R
) != 0
310 && ((*p
)->flags() & elfcpp::PF_W
) == 0)
314 Output_segment
* load_seg
= new Output_segment(elfcpp::PT_LOAD
, elfcpp::PF_R
);
315 this->segment_list_
.push_back(load_seg
);
319 // Finalize the layout. When this is called, we have created all the
320 // output sections and all the output segments which are based on
321 // input sections. We have several things to do, and we have to do
322 // them in the right order, so that we get the right results correctly
325 // 1) Finalize the list of output segments and create the segment
328 // 2) Finalize the dynamic symbol table and associated sections.
330 // 3) Determine the final file offset of all the output segments.
332 // 4) Determine the final file offset of all the SHF_ALLOC output
335 // 5) Create the symbol table sections and the section name table
338 // 6) Finalize the symbol table: set symbol values to their final
339 // value and make a final determination of which symbols are going
340 // into the output symbol table.
342 // 7) Create the section table header.
344 // 8) Determine the final file offset of all the output sections which
345 // are not SHF_ALLOC, including the section table header.
347 // 9) Finalize the ELF file header.
349 // This function returns the size of the output file.
352 Layout::finalize(const Input_objects
* input_objects
, Symbol_table
* symtab
)
354 if (input_objects
->any_dynamic())
356 // If there are any dynamic objects in the link, then we need
357 // some additional segments: PT_PHDRS, PT_INTERP, and
358 // PT_DYNAMIC. We also need to finalize the dynamic symbol
359 // table and create the dynamic hash table.
363 // FIXME: Handle PT_GNU_STACK.
365 Output_segment
* load_seg
= this->find_first_load_seg();
367 // Lay out the segment headers.
368 int size
= input_objects
->target()->get_size();
369 bool big_endian
= input_objects
->target()->is_big_endian();
370 Output_segment_headers
* segment_headers
;
371 segment_headers
= new Output_segment_headers(size
, big_endian
,
372 this->segment_list_
);
373 load_seg
->add_initial_output_data(segment_headers
);
374 this->special_output_list_
.push_back(segment_headers
);
375 // FIXME: Attach them to PT_PHDRS if necessary.
377 // Lay out the file header.
378 Output_file_header
* file_header
;
379 file_header
= new Output_file_header(size
,
382 input_objects
->target(),
385 load_seg
->add_initial_output_data(file_header
);
386 this->special_output_list_
.push_back(file_header
);
388 // We set the output section indexes in set_segment_offsets and
389 // set_section_offsets.
390 unsigned int shndx
= 1;
392 // Set the file offsets of all the segments, and all the sections
394 off_t off
= this->set_segment_offsets(input_objects
->target(), load_seg
,
397 // Create the symbol table sections.
398 // FIXME: We don't need to do this if we are stripping symbols.
399 Output_section
* osymtab
;
400 Output_section
* ostrtab
;
401 this->create_symtab_sections(size
, input_objects
, symtab
, &off
,
404 // Create the .shstrtab section.
405 Output_section
* shstrtab_section
= this->create_shstrtab();
407 // Set the file offsets of all the sections not associated with
409 off
= this->set_section_offsets(off
, &shndx
);
411 // Now the section index of OSTRTAB is set.
412 osymtab
->set_link(ostrtab
->out_shndx());
414 // Create the section table header.
415 Output_section_headers
* oshdrs
= this->create_shdrs(size
, big_endian
, &off
);
417 file_header
->set_section_info(oshdrs
, shstrtab_section
);
419 // Now we know exactly where everything goes in the output file.
424 // Return whether SEG1 should be before SEG2 in the output file. This
425 // is based entirely on the segment type and flags. When this is
426 // called the segment addresses has normally not yet been set.
429 Layout::segment_precedes(const Output_segment
* seg1
,
430 const Output_segment
* seg2
)
432 elfcpp::Elf_Word type1
= seg1
->type();
433 elfcpp::Elf_Word type2
= seg2
->type();
435 // The single PT_PHDR segment is required to precede any loadable
436 // segment. We simply make it always first.
437 if (type1
== elfcpp::PT_PHDR
)
439 assert(type2
!= elfcpp::PT_PHDR
);
442 if (type2
== elfcpp::PT_PHDR
)
445 // The single PT_INTERP segment is required to precede any loadable
446 // segment. We simply make it always second.
447 if (type1
== elfcpp::PT_INTERP
)
449 assert(type2
!= elfcpp::PT_INTERP
);
452 if (type2
== elfcpp::PT_INTERP
)
455 // We then put PT_LOAD segments before any other segments.
456 if (type1
== elfcpp::PT_LOAD
&& type2
!= elfcpp::PT_LOAD
)
458 if (type2
== elfcpp::PT_LOAD
&& type1
!= elfcpp::PT_LOAD
)
461 // We put the PT_TLS segment last, because that is where the dynamic
462 // linker expects to find it (this is just for efficiency; other
463 // positions would also work correctly).
464 if (type1
== elfcpp::PT_TLS
&& type2
!= elfcpp::PT_TLS
)
466 if (type2
== elfcpp::PT_TLS
&& type1
!= elfcpp::PT_TLS
)
469 const elfcpp::Elf_Word flags1
= seg1
->flags();
470 const elfcpp::Elf_Word flags2
= seg2
->flags();
472 // The order of non-PT_LOAD segments is unimportant. We simply sort
473 // by the numeric segment type and flags values. There should not
474 // be more than one segment with the same type and flags.
475 if (type1
!= elfcpp::PT_LOAD
)
478 return type1
< type2
;
479 assert(flags1
!= flags2
);
480 return flags1
< flags2
;
483 // We sort PT_LOAD segments based on the flags. Readonly segments
484 // come before writable segments. Then executable segments come
485 // before non-executable segments. Then the unlikely case of a
486 // non-readable segment comes before the normal case of a readable
487 // segment. If there are multiple segments with the same type and
488 // flags, we require that the address be set, and we sort by
489 // virtual address and then physical address.
490 if ((flags1
& elfcpp::PF_W
) != (flags2
& elfcpp::PF_W
))
491 return (flags1
& elfcpp::PF_W
) == 0;
492 if ((flags1
& elfcpp::PF_X
) != (flags2
& elfcpp::PF_X
))
493 return (flags1
& elfcpp::PF_X
) != 0;
494 if ((flags1
& elfcpp::PF_R
) != (flags2
& elfcpp::PF_R
))
495 return (flags1
& elfcpp::PF_R
) == 0;
497 uint64_t vaddr1
= seg1
->vaddr();
498 uint64_t vaddr2
= seg2
->vaddr();
499 if (vaddr1
!= vaddr2
)
500 return vaddr1
< vaddr2
;
502 uint64_t paddr1
= seg1
->paddr();
503 uint64_t paddr2
= seg2
->paddr();
504 assert(paddr1
!= paddr2
);
505 return paddr1
< paddr2
;
508 // Set the file offsets of all the segments, and all the sections they
509 // contain. They have all been created. LOAD_SEG must be be laid out
510 // first. Return the offset of the data to follow.
513 Layout::set_segment_offsets(const Target
* target
, Output_segment
* load_seg
,
514 unsigned int *pshndx
)
516 // Sort them into the final order.
517 std::sort(this->segment_list_
.begin(), this->segment_list_
.end(),
518 Layout::Compare_segments());
520 // Find the PT_LOAD segments, and set their addresses and offsets
521 // and their section's addresses and offsets.
522 uint64_t addr
= target
->text_segment_address();
524 bool was_readonly
= false;
525 for (Segment_list::iterator p
= this->segment_list_
.begin();
526 p
!= this->segment_list_
.end();
529 if ((*p
)->type() == elfcpp::PT_LOAD
)
531 if (load_seg
!= NULL
&& load_seg
!= *p
)
535 // If the last segment was readonly, and this one is not,
536 // then skip the address forward one page, maintaining the
537 // same position within the page. This lets us store both
538 // segments overlapping on a single page in the file, but
539 // the loader will put them on different pages in memory.
541 uint64_t orig_addr
= addr
;
542 uint64_t orig_off
= off
;
544 uint64_t aligned_addr
= addr
;
545 uint64_t abi_pagesize
= target
->abi_pagesize();
546 if (was_readonly
&& ((*p
)->flags() & elfcpp::PF_W
) != 0)
548 uint64_t align
= (*p
)->addralign();
550 addr
= align_address(addr
, align
);
552 if ((addr
& (abi_pagesize
- 1)) != 0)
553 addr
= addr
+ abi_pagesize
;
556 unsigned int shndx_hold
= *pshndx
;
557 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
558 uint64_t new_addr
= (*p
)->set_section_addresses(addr
, &off
, pshndx
);
560 // Now that we know the size of this segment, we may be able
561 // to save a page in memory, at the cost of wasting some
562 // file space, by instead aligning to the start of a new
563 // page. Here we use the real machine page size rather than
564 // the ABI mandated page size.
566 if (aligned_addr
!= addr
)
568 uint64_t common_pagesize
= target
->common_pagesize();
569 uint64_t first_off
= (common_pagesize
571 & (common_pagesize
- 1)));
572 uint64_t last_off
= new_addr
& (common_pagesize
- 1);
575 && ((aligned_addr
& ~ (common_pagesize
- 1))
576 != (new_addr
& ~ (common_pagesize
- 1)))
577 && first_off
+ last_off
<= common_pagesize
)
579 *pshndx
= shndx_hold
;
580 addr
= align_address(aligned_addr
, common_pagesize
);
581 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
582 new_addr
= (*p
)->set_section_addresses(addr
, &off
, pshndx
);
588 if (((*p
)->flags() & elfcpp::PF_W
) == 0)
593 // Handle the non-PT_LOAD segments, setting their offsets from their
594 // section's offsets.
595 for (Segment_list::iterator p
= this->segment_list_
.begin();
596 p
!= this->segment_list_
.end();
599 if ((*p
)->type() != elfcpp::PT_LOAD
)
606 // Set the file offset of all the sections not associated with a
610 Layout::set_section_offsets(off_t off
, unsigned int* pshndx
)
612 for (Layout::Section_list::iterator p
= this->section_list_
.begin();
613 p
!= this->section_list_
.end();
616 (*p
)->set_out_shndx(*pshndx
);
618 if ((*p
)->offset() != -1)
620 off
= align_address(off
, (*p
)->addralign());
621 (*p
)->set_address(0, off
);
622 off
+= (*p
)->data_size();
627 // Create the symbol table sections.
630 Layout::create_symtab_sections(int size
, const Input_objects
* input_objects
,
631 Symbol_table
* symtab
,
633 Output_section
** posymtab
,
634 Output_section
** postrtab
)
640 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
645 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
652 off
= align_address(off
, align
);
653 off_t startoff
= off
;
655 // Save space for the dummy symbol at the start of the section. We
656 // never bother to write this out--it will just be left as zero.
659 for (Input_objects::Object_list::const_iterator p
= input_objects
->begin();
660 p
!= input_objects
->end();
663 Task_lock_obj
<Object
> tlo(**p
);
664 off
= (*p
)->finalize_local_symbols(off
, &this->sympool_
);
667 unsigned int local_symcount
= (off
- startoff
) / symsize
;
668 assert(local_symcount
* symsize
== off
- startoff
);
670 off
= symtab
->finalize(off
, &this->sympool_
);
672 this->sympool_
.set_string_offsets();
674 const char* symtab_name
= this->namepool_
.add(".symtab");
675 Output_section
* osymtab
= new Output_section_symtab(symtab_name
,
677 this->section_list_
.push_back(osymtab
);
679 const char* strtab_name
= this->namepool_
.add(".strtab");
680 Output_section
*ostrtab
= new Output_section_strtab(strtab_name
,
682 this->section_list_
.push_back(ostrtab
);
683 this->special_output_list_
.push_back(ostrtab
);
685 osymtab
->set_address(0, startoff
);
686 osymtab
->set_info(local_symcount
);
687 osymtab
->set_entsize(symsize
);
688 osymtab
->set_addralign(align
);
695 // Create the .shstrtab section, which holds the names of the
696 // sections. At the time this is called, we have created all the
697 // output sections except .shstrtab itself.
700 Layout::create_shstrtab()
702 // FIXME: We don't need to create a .shstrtab section if we are
703 // stripping everything.
705 const char* name
= this->namepool_
.add(".shstrtab");
707 this->namepool_
.set_string_offsets();
709 Output_section
* os
= new Output_section_strtab(name
, &this->namepool_
);
711 this->section_list_
.push_back(os
);
712 this->special_output_list_
.push_back(os
);
717 // Create the section headers. SIZE is 32 or 64. OFF is the file
720 Output_section_headers
*
721 Layout::create_shdrs(int size
, bool big_endian
, off_t
* poff
)
723 Output_section_headers
* oshdrs
;
724 oshdrs
= new Output_section_headers(size
, big_endian
, this->segment_list_
,
727 off_t off
= align_address(*poff
, oshdrs
->addralign());
728 oshdrs
->set_address(0, off
);
729 off
+= oshdrs
->data_size();
731 this->special_output_list_
.push_back(oshdrs
);
735 // The mapping of .gnu.linkonce section names to real section names.
737 #define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
738 const Layout::Linkonce_mapping
Layout::linkonce_mapping
[] =
740 MAPPING_INIT("d.rel.ro", ".data.rel.ro"), // Must be before "d".
741 MAPPING_INIT("t", ".text"),
742 MAPPING_INIT("r", ".rodata"),
743 MAPPING_INIT("d", ".data"),
744 MAPPING_INIT("b", ".bss"),
745 MAPPING_INIT("s", ".sdata"),
746 MAPPING_INIT("sb", ".sbss"),
747 MAPPING_INIT("s2", ".sdata2"),
748 MAPPING_INIT("sb2", ".sbss2"),
749 MAPPING_INIT("wi", ".debug_info"),
750 MAPPING_INIT("td", ".tdata"),
751 MAPPING_INIT("tb", ".tbss"),
752 MAPPING_INIT("lr", ".lrodata"),
753 MAPPING_INIT("l", ".ldata"),
754 MAPPING_INIT("lb", ".lbss"),
758 const int Layout::linkonce_mapping_count
=
759 sizeof(Layout::linkonce_mapping
) / sizeof(Layout::linkonce_mapping
[0]);
761 // Return the name of the output section to use for a .gnu.linkonce
762 // section. This is based on the default ELF linker script of the old
763 // GNU linker. For example, we map a name like ".gnu.linkonce.t.foo"
764 // to ".text". Set *PLEN to the length of the name. *PLEN is
765 // initialized to the length of NAME.
768 Layout::linkonce_output_name(const char* name
, size_t *plen
)
770 const char* s
= name
+ sizeof(".gnu.linkonce") - 1;
774 const Linkonce_mapping
* plm
= linkonce_mapping
;
775 for (int i
= 0; i
< linkonce_mapping_count
; ++i
, ++plm
)
777 if (strncmp(s
, plm
->from
, plm
->fromlen
) == 0 && s
[plm
->fromlen
] == '.')
786 // Choose the output section name to use given an input section name.
787 // Set *PLEN to the length of the name. *PLEN is initialized to the
791 Layout::output_section_name(const char* name
, size_t* plen
)
793 if (Layout::is_linkonce(name
))
795 // .gnu.linkonce sections are laid out as though they were named
796 // for the sections are placed into.
797 return Layout::linkonce_output_name(name
, plen
);
800 // If the section name has no '.', or only an initial '.', we use
801 // the name unchanged (i.e., ".text" is unchanged).
803 // Otherwise, if the section name does not include ".rel", we drop
804 // the last '.' and everything that follows (i.e., ".text.XXX"
807 // Otherwise, if the section name has zero or one '.' after the
808 // ".rel", we use the name unchanged (i.e., ".rel.text" is
811 // Otherwise, we drop the last '.' and everything that follows
812 // (i.e., ".rel.text.XXX" becomes ".rel.text").
814 const char* s
= name
;
817 const char* sdot
= strchr(s
, '.');
821 const char* srel
= strstr(s
, ".rel");
828 sdot
= strchr(srel
+ 1, '.');
831 sdot
= strchr(sdot
+ 1, '.');
839 // Record the signature of a comdat section, and return whether to
840 // include it in the link. If GROUP is true, this is a regular
841 // section group. If GROUP is false, this is a group signature
842 // derived from the name of a linkonce section. We want linkonce
843 // signatures and group signatures to block each other, but we don't
844 // want a linkonce signature to block another linkonce signature.
847 Layout::add_comdat(const char* signature
, bool group
)
849 std::string
sig(signature
);
850 std::pair
<Signatures::iterator
, bool> ins(
851 this->signatures_
.insert(std::make_pair(sig
, group
)));
855 // This is the first time we've seen this signature.
859 if (ins
.first
->second
)
861 // We've already seen a real section group with this signature.
866 // This is a real section group, and we've already seen a
867 // linkonce section with tihs signature. Record that we've seen
868 // a section group, and don't include this section group.
869 ins
.first
->second
= true;
874 // We've already seen a linkonce section and this is a linkonce
875 // section. These don't block each other--this may be the same
876 // symbol name with different section types.
881 // Write out data not associated with a section or the symbol table.
884 Layout::write_data(Output_file
* of
) const
886 for (Data_list::const_iterator p
= this->special_output_list_
.begin();
887 p
!= this->special_output_list_
.end();
892 // Write_data_task methods.
894 // We can always run this task.
896 Task::Is_runnable_type
897 Write_data_task::is_runnable(Workqueue
*)
902 // We need to unlock FINAL_BLOCKER when finished.
905 Write_data_task::locks(Workqueue
* workqueue
)
907 return new Task_locker_block(*this->final_blocker_
, workqueue
);
910 // Run the task--write out the data.
913 Write_data_task::run(Workqueue
*)
915 this->layout_
->write_data(this->of_
);
918 // Write_symbols_task methods.
920 // We can always run this task.
922 Task::Is_runnable_type
923 Write_symbols_task::is_runnable(Workqueue
*)
928 // We need to unlock FINAL_BLOCKER when finished.
931 Write_symbols_task::locks(Workqueue
* workqueue
)
933 return new Task_locker_block(*this->final_blocker_
, workqueue
);
936 // Run the task--write out the symbols.
939 Write_symbols_task::run(Workqueue
*)
941 this->symtab_
->write_globals(this->target_
, this->sympool_
, this->of_
);
944 // Close_task_runner methods.
946 // Run the task--close the file.
949 Close_task_runner::run(Workqueue
*)
954 // Instantiate the templates we need. We could use the configure
955 // script to restrict this to only the ones for implemented targets.
959 Layout::layout
<32, false>(Object
* object
, unsigned int shndx
, const char* name
,
960 const elfcpp::Shdr
<32, false>& shdr
, off_t
*);
964 Layout::layout
<32, true>(Object
* object
, unsigned int shndx
, const char* name
,
965 const elfcpp::Shdr
<32, true>& shdr
, off_t
*);
969 Layout::layout
<64, false>(Object
* object
, unsigned int shndx
, const char* name
,
970 const elfcpp::Shdr
<64, false>& shdr
, off_t
*);
974 Layout::layout
<64, true>(Object
* object
, unsigned int shndx
, const char* name
,
975 const elfcpp::Shdr
<64, true>& shdr
, off_t
*);
978 } // End namespace gold.