1 // inremental.cc -- incremental linking support for gold
3 // Copyright 2009, 2010 Free Software Foundation, Inc.
4 // Written by Mikolaj Zalewski <mikolajz@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.
26 #include "libiberty.h"
31 #include "incremental.h"
34 #include "target-select.h"
39 // Version information. Will change frequently during the development, later
40 // we could think about backward (and forward?) compatibility.
41 const unsigned int INCREMENTAL_LINK_VERSION
= 1;
43 // This class manages the .gnu_incremental_inputs section, which holds
44 // the header information, a directory of input files, and separate
45 // entries for each input file.
47 template<int size
, bool big_endian
>
48 class Output_section_incremental_inputs
: public Output_section_data
51 Output_section_incremental_inputs(const Incremental_inputs
* inputs
,
52 const Symbol_table
* symtab
)
53 : Output_section_data(size
/ 8), inputs_(inputs
), symtab_(symtab
)
57 // Set the final data size.
59 set_final_data_size();
61 // Write the data to the file.
63 do_write(Output_file
*);
65 // Write to a map file.
67 do_print_to_mapfile(Mapfile
* mapfile
) const
68 { mapfile
->print_output_data(this, _("** incremental_inputs")); }
71 // Write the section header.
73 write_header(unsigned char* pov
, unsigned int input_file_count
,
74 section_offset_type command_line_offset
);
76 // Write the input file entries.
78 write_input_files(unsigned char* oview
, unsigned char* pov
,
81 // Write the supplemental information blocks.
83 write_info_blocks(unsigned char* oview
, unsigned char* pov
,
84 Stringpool
* strtab
, unsigned int* global_syms
,
85 unsigned int global_sym_count
);
87 // Write the contents of the .gnu_incremental_symtab section.
89 write_symtab(unsigned char* pov
, unsigned int* global_syms
,
90 unsigned int global_sym_count
);
92 // Write the contents of the .gnu_incremental_got_plt section.
94 write_got_plt(unsigned char* pov
, off_t view_size
);
96 // Typedefs for writing the data to the output sections.
97 typedef elfcpp::Swap
<size
, big_endian
> Swap
;
98 typedef elfcpp::Swap
<16, big_endian
> Swap16
;
99 typedef elfcpp::Swap
<32, big_endian
> Swap32
;
100 typedef elfcpp::Swap
<64, big_endian
> Swap64
;
102 // Sizes of various structures.
103 static const int sizeof_addr
= size
/ 8;
104 static const int header_size
= 16;
105 static const int input_entry_size
= 24;
107 // The Incremental_inputs object.
108 const Incremental_inputs
* inputs_
;
111 const Symbol_table
* symtab_
;
114 // Inform the user why we don't do an incremental link. Not called in
115 // the obvious case of missing output file. TODO: Is this helpful?
118 vexplain_no_incremental(const char* format
, va_list args
)
121 if (vasprintf(&buf
, format
, args
) < 0)
123 gold_info(_("the link might take longer: "
124 "cannot perform incremental link: %s"), buf
);
129 explain_no_incremental(const char* format
, ...)
132 va_start(args
, format
);
133 vexplain_no_incremental(format
, args
);
140 Incremental_binary::error(const char* format
, ...) const
143 va_start(args
, format
);
144 // Current code only checks if the file can be used for incremental linking,
145 // so errors shouldn't fail the build, but only result in a fallback to a
147 // TODO: when we implement incremental editing of the file, we may need a
148 // flag that will cause errors to be treated seriously.
149 vexplain_no_incremental(format
, args
);
153 // Find the .gnu_incremental_inputs section and related sections.
155 template<int size
, bool big_endian
>
157 Sized_incremental_binary
<size
, big_endian
>::do_find_incremental_inputs_sections(
158 unsigned int* p_inputs_shndx
,
159 unsigned int* p_symtab_shndx
,
160 unsigned int* p_relocs_shndx
,
161 unsigned int* p_got_plt_shndx
,
162 unsigned int* p_strtab_shndx
)
164 unsigned int inputs_shndx
=
165 this->elf_file_
.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_INPUTS
);
166 if (inputs_shndx
== elfcpp::SHN_UNDEF
) // Not found.
169 unsigned int symtab_shndx
=
170 this->elf_file_
.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_SYMTAB
);
171 if (symtab_shndx
== elfcpp::SHN_UNDEF
) // Not found.
173 if (this->elf_file_
.section_link(symtab_shndx
) != inputs_shndx
)
176 unsigned int relocs_shndx
=
177 this->elf_file_
.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_RELOCS
);
178 if (relocs_shndx
== elfcpp::SHN_UNDEF
) // Not found.
180 if (this->elf_file_
.section_link(relocs_shndx
) != inputs_shndx
)
183 unsigned int got_plt_shndx
=
184 this->elf_file_
.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT
);
185 if (got_plt_shndx
== elfcpp::SHN_UNDEF
) // Not found.
187 if (this->elf_file_
.section_link(got_plt_shndx
) != inputs_shndx
)
190 unsigned int strtab_shndx
= this->elf_file_
.section_link(inputs_shndx
);
191 if (strtab_shndx
== elfcpp::SHN_UNDEF
192 || strtab_shndx
> this->elf_file_
.shnum()
193 || this->elf_file_
.section_type(strtab_shndx
) != elfcpp::SHT_STRTAB
)
196 if (p_inputs_shndx
!= NULL
)
197 *p_inputs_shndx
= inputs_shndx
;
198 if (p_symtab_shndx
!= NULL
)
199 *p_symtab_shndx
= symtab_shndx
;
200 if (p_relocs_shndx
!= NULL
)
201 *p_relocs_shndx
= relocs_shndx
;
202 if (p_got_plt_shndx
!= NULL
)
203 *p_got_plt_shndx
= got_plt_shndx
;
204 if (p_strtab_shndx
!= NULL
)
205 *p_strtab_shndx
= strtab_shndx
;
209 // Determine whether an incremental link based on the existing output file
212 template<int size
, bool big_endian
>
214 Sized_incremental_binary
<size
, big_endian
>::do_check_inputs(
215 Incremental_inputs
* incremental_inputs
)
217 unsigned int inputs_shndx
;
218 unsigned int symtab_shndx
;
219 unsigned int relocs_shndx
;
220 unsigned int plt_got_shndx
;
221 unsigned int strtab_shndx
;
223 if (!do_find_incremental_inputs_sections(&inputs_shndx
, &symtab_shndx
,
224 &relocs_shndx
, &plt_got_shndx
,
227 explain_no_incremental(_("no incremental data from previous build"));
231 Location
inputs_location(this->elf_file_
.section_contents(inputs_shndx
));
232 Location
symtab_location(this->elf_file_
.section_contents(symtab_shndx
));
233 Location
relocs_location(this->elf_file_
.section_contents(relocs_shndx
));
234 Location
strtab_location(this->elf_file_
.section_contents(strtab_shndx
));
236 View
inputs_view(view(inputs_location
));
237 View
symtab_view(view(symtab_location
));
238 View
relocs_view(view(relocs_location
));
239 View
strtab_view(view(strtab_location
));
241 elfcpp::Elf_strtab
strtab(strtab_view
.data(), strtab_location
.data_size
);
243 Incremental_inputs_reader
<size
, big_endian
>
244 incoming_inputs(inputs_view
.data(), strtab
);
246 if (incoming_inputs
.version() != INCREMENTAL_LINK_VERSION
)
248 explain_no_incremental(_("different version of incremental build data"));
252 if (incremental_inputs
->command_line() != incoming_inputs
.command_line())
254 explain_no_incremental(_("command line changed"));
258 // TODO: compare incremental_inputs->inputs() with entries in data_view.
266 // Create a Sized_incremental_binary object of the specified size and
267 // endianness. Fails if the target architecture is not supported.
269 template<int size
, bool big_endian
>
271 make_sized_incremental_binary(Output_file
* file
,
272 const elfcpp::Ehdr
<size
, big_endian
>& ehdr
)
274 Target
* target
= select_target(ehdr
.get_e_machine(), size
, big_endian
,
275 ehdr
.get_e_ident()[elfcpp::EI_OSABI
],
276 ehdr
.get_e_ident()[elfcpp::EI_ABIVERSION
]);
279 explain_no_incremental(_("unsupported ELF machine number %d"),
280 ehdr
.get_e_machine());
284 if (!parameters
->target_valid())
285 set_parameters_target(target
);
286 else if (target
!= ¶meters
->target())
287 gold_error(_("%s: incompatible target"), file
->filename());
289 return new Sized_incremental_binary
<size
, big_endian
>(file
, ehdr
, target
);
292 } // End of anonymous namespace.
294 // Create an Incremental_binary object for FILE. Returns NULL is this is not
295 // possible, e.g. FILE is not an ELF file or has an unsupported target. FILE
299 open_incremental_binary(Output_file
* file
)
301 off_t filesize
= file
->filesize();
302 int want
= elfcpp::Elf_recognizer::max_header_size
;
306 const unsigned char* p
= file
->get_input_view(0, want
);
307 if (!elfcpp::Elf_recognizer::is_elf_file(p
, want
))
309 explain_no_incremental(_("output is not an ELF file."));
314 bool big_endian
= false;
316 if (!elfcpp::Elf_recognizer::is_valid_header(p
, want
, &size
, &big_endian
,
319 explain_no_incremental(error
.c_str());
323 Incremental_binary
* result
= NULL
;
328 #ifdef HAVE_TARGET_32_BIG
329 result
= make_sized_incremental_binary
<32, true>(
330 file
, elfcpp::Ehdr
<32, true>(p
));
332 explain_no_incremental(_("unsupported file: 32-bit, big-endian"));
337 #ifdef HAVE_TARGET_32_LITTLE
338 result
= make_sized_incremental_binary
<32, false>(
339 file
, elfcpp::Ehdr
<32, false>(p
));
341 explain_no_incremental(_("unsupported file: 32-bit, little-endian"));
349 #ifdef HAVE_TARGET_64_BIG
350 result
= make_sized_incremental_binary
<64, true>(
351 file
, elfcpp::Ehdr
<64, true>(p
));
353 explain_no_incremental(_("unsupported file: 64-bit, big-endian"));
358 #ifdef HAVE_TARGET_64_LITTLE
359 result
= make_sized_incremental_binary
<64, false>(
360 file
, elfcpp::Ehdr
<64, false>(p
));
362 explain_no_incremental(_("unsupported file: 64-bit, little-endian"));
372 // Analyzes the output file to check if incremental linking is possible and
373 // (to be done) what files need to be relinked.
376 Incremental_checker::can_incrementally_link_output_file()
378 Output_file
output(this->output_name_
);
379 if (!output
.open_for_modification())
381 Incremental_binary
* binary
= open_incremental_binary(&output
);
384 return binary
->check_inputs(this->incremental_inputs_
);
387 // Class Incremental_inputs.
389 // Add the command line to the string table, setting
390 // command_line_key_. In incremental builds, the command line is
391 // stored in .gnu_incremental_inputs so that the next linker run can
392 // check if the command line options didn't change.
395 Incremental_inputs::report_command_line(int argc
, const char* const* argv
)
397 // Always store 'gold' as argv[0] to avoid a full relink if the user used a
398 // different path to the linker.
399 std::string
args("gold");
400 // Copied from collect_argv in main.cc.
401 for (int i
= 1; i
< argc
; ++i
)
403 // Adding/removing these options should not result in a full relink.
404 if (strcmp(argv
[i
], "--incremental") == 0
405 || strcmp(argv
[i
], "--incremental-full") == 0
406 || strcmp(argv
[i
], "--incremental-update") == 0
407 || strcmp(argv
[i
], "--incremental-changed") == 0
408 || strcmp(argv
[i
], "--incremental-unchanged") == 0
409 || strcmp(argv
[i
], "--incremental-unknown") == 0)
413 // Now append argv[i], but with all single-quotes escaped
414 const char* argpos
= argv
[i
];
417 const int len
= strcspn(argpos
, "'");
418 args
.append(argpos
, len
);
419 if (argpos
[len
] == '\0')
421 args
.append("'\"'\"'");
427 this->command_line_
= args
;
428 this->strtab_
->add(this->command_line_
.c_str(), false,
429 &this->command_line_key_
);
432 // Record the input archive file ARCHIVE. This is called by the
433 // Add_archive_symbols task before determining which archive members
434 // to include. We create the Incremental_archive_entry here and
435 // attach it to the Archive, but we do not add it to the list of
436 // input objects until report_archive_end is called.
439 Incremental_inputs::report_archive_begin(Library_base
* arch
,
440 Script_info
* script_info
)
442 Stringpool::Key filename_key
;
443 Timespec mtime
= arch
->get_mtime();
445 this->strtab_
->add(arch
->filename().c_str(), false, &filename_key
);
446 Incremental_archive_entry
* entry
=
447 new Incremental_archive_entry(filename_key
, mtime
);
448 arch
->set_incremental_info(entry
);
449 this->inputs_
.push_back(entry
);
451 if (script_info
!= NULL
)
453 Incremental_script_entry
* script_entry
= script_info
->incremental_info();
454 gold_assert(script_entry
!= NULL
);
455 script_entry
->add_object(entry
);
459 // Visitor class for processing the unused global symbols in a library.
460 // An instance of this class is passed to the library's
461 // for_all_unused_symbols() iterator, which will call the visit()
462 // function for each global symbol defined in each unused library
463 // member. We add those symbol names to the incremental info for the
466 class Unused_symbol_visitor
: public Library_base::Symbol_visitor_base
469 Unused_symbol_visitor(Incremental_archive_entry
* entry
, Stringpool
* strtab
)
470 : entry_(entry
), strtab_(strtab
)
474 visit(const char* sym
)
476 Stringpool::Key symbol_key
;
477 this->strtab_
->add(sym
, true, &symbol_key
);
478 this->entry_
->add_unused_global_symbol(symbol_key
);
482 Incremental_archive_entry
* entry_
;
486 // Finish recording the input archive file ARCHIVE. This is called by the
487 // Add_archive_symbols task after determining which archive members
491 Incremental_inputs::report_archive_end(Library_base
* arch
)
493 Incremental_archive_entry
* entry
= arch
->incremental_info();
495 gold_assert(entry
!= NULL
);
497 // Collect unused global symbols.
498 Unused_symbol_visitor
v(entry
, this->strtab_
);
499 arch
->for_all_unused_symbols(&v
);
502 // Record the input object file OBJ. If ARCH is not NULL, attach
503 // the object file to the archive. This is called by the
504 // Add_symbols task after finding out the type of the file.
507 Incremental_inputs::report_object(Object
* obj
, Library_base
* arch
,
508 Script_info
* script_info
)
510 Stringpool::Key filename_key
;
511 Timespec mtime
= obj
->input_file()->file().get_mtime();
513 this->strtab_
->add(obj
->name().c_str(), false, &filename_key
);
514 Incremental_object_entry
* obj_entry
=
515 new Incremental_object_entry(filename_key
, obj
, mtime
);
516 this->inputs_
.push_back(obj_entry
);
520 Incremental_archive_entry
* arch_entry
= arch
->incremental_info();
521 gold_assert(arch_entry
!= NULL
);
522 arch_entry
->add_object(obj_entry
);
525 if (script_info
!= NULL
)
527 Incremental_script_entry
* script_entry
= script_info
->incremental_info();
528 gold_assert(script_entry
!= NULL
);
529 script_entry
->add_object(obj_entry
);
532 this->current_object_
= obj
;
533 this->current_object_entry_
= obj_entry
;
536 // Record the input object file OBJ. If ARCH is not NULL, attach
537 // the object file to the archive. This is called by the
538 // Add_symbols task after finding out the type of the file.
541 Incremental_inputs::report_input_section(Object
* obj
, unsigned int shndx
,
542 const char* name
, off_t sh_size
)
544 Stringpool::Key key
= 0;
547 this->strtab_
->add(name
, true, &key
);
549 gold_assert(obj
== this->current_object_
);
550 this->current_object_entry_
->add_input_section(shndx
, key
, sh_size
);
553 // Record that the input argument INPUT is a script SCRIPT. This is
554 // called by read_script after parsing the script and reading the list
555 // of inputs added by this script.
558 Incremental_inputs::report_script(const std::string
& filename
,
559 Script_info
* script
, Timespec mtime
)
561 Stringpool::Key filename_key
;
563 this->strtab_
->add(filename
.c_str(), false, &filename_key
);
564 Incremental_script_entry
* entry
=
565 new Incremental_script_entry(filename_key
, script
, mtime
);
566 this->inputs_
.push_back(entry
);
567 script
->set_incremental_info(entry
);
570 // Finalize the incremental link information. Called from
574 Incremental_inputs::finalize()
576 // Finalize the string table.
577 this->strtab_
->set_string_offsets();
580 // Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
583 Incremental_inputs::create_data_sections(Symbol_table
* symtab
)
585 switch (parameters
->size_and_endianness())
587 #ifdef HAVE_TARGET_32_LITTLE
588 case Parameters::TARGET_32_LITTLE
:
589 this->inputs_section_
=
590 new Output_section_incremental_inputs
<32, false>(this, symtab
);
593 #ifdef HAVE_TARGET_32_BIG
594 case Parameters::TARGET_32_BIG
:
595 this->inputs_section_
=
596 new Output_section_incremental_inputs
<32, true>(this, symtab
);
599 #ifdef HAVE_TARGET_64_LITTLE
600 case Parameters::TARGET_64_LITTLE
:
601 this->inputs_section_
=
602 new Output_section_incremental_inputs
<64, false>(this, symtab
);
605 #ifdef HAVE_TARGET_64_BIG
606 case Parameters::TARGET_64_BIG
:
607 this->inputs_section_
=
608 new Output_section_incremental_inputs
<64, true>(this, symtab
);
614 this->symtab_section_
= new Output_data_space(4, "** incremental_symtab");
615 this->relocs_section_
= new Output_data_space(4, "** incremental_relocs");
616 this->got_plt_section_
= new Output_data_space(4, "** incremental_got_plt");
619 // Return the sh_entsize value for the .gnu_incremental_relocs section.
621 Incremental_inputs::relocs_entsize() const
623 return 8 + 2 * parameters
->target().get_size() / 8;
626 // Class Output_section_incremental_inputs.
628 // Finalize the offsets for each input section and supplemental info block,
629 // and set the final data size of the incremental output sections.
631 template<int size
, bool big_endian
>
633 Output_section_incremental_inputs
<size
, big_endian
>::set_final_data_size()
635 const Incremental_inputs
* inputs
= this->inputs_
;
636 const unsigned int sizeof_addr
= size
/ 8;
637 const unsigned int rel_size
= 8 + 2 * sizeof_addr
;
639 // Offset of each input entry.
640 unsigned int input_offset
= this->header_size
;
642 // Offset of each supplemental info block.
643 unsigned int info_offset
= this->header_size
;
644 info_offset
+= this->input_entry_size
* inputs
->input_file_count();
646 // Count each input file and its supplemental information block.
647 for (Incremental_inputs::Input_list::const_iterator p
=
648 inputs
->input_files().begin();
649 p
!= inputs
->input_files().end();
652 // Set the offset of the input file entry.
653 (*p
)->set_offset(input_offset
);
654 input_offset
+= this->input_entry_size
;
656 // Set the offset of the supplemental info block.
657 switch ((*p
)->type())
659 case INCREMENTAL_INPUT_SCRIPT
:
661 Incremental_script_entry
*entry
= (*p
)->script_entry();
662 gold_assert(entry
!= NULL
);
663 (*p
)->set_info_offset(info_offset
);
667 info_offset
+= (entry
->get_object_count() * 4);
670 case INCREMENTAL_INPUT_OBJECT
:
671 case INCREMENTAL_INPUT_ARCHIVE_MEMBER
:
673 Incremental_object_entry
* entry
= (*p
)->object_entry();
674 gold_assert(entry
!= NULL
);
675 (*p
)->set_info_offset(info_offset
);
676 // Input section count + global symbol count.
678 // Each input section.
679 info_offset
+= (entry
->get_input_section_count()
680 * (8 + 2 * sizeof_addr
));
681 // Each global symbol.
682 const Object::Symbols
* syms
= entry
->object()->get_global_symbols();
683 info_offset
+= syms
->size() * 16;
686 case INCREMENTAL_INPUT_SHARED_LIBRARY
:
688 Incremental_object_entry
* entry
= (*p
)->object_entry();
689 gold_assert(entry
!= NULL
);
690 (*p
)->set_info_offset(info_offset
);
691 // Global symbol count.
693 // Each global symbol.
694 const Object::Symbols
* syms
= entry
->object()->get_global_symbols();
695 unsigned int nsyms
= syms
!= NULL
? syms
->size() : 0;
696 info_offset
+= nsyms
* 4;
699 case INCREMENTAL_INPUT_ARCHIVE
:
701 Incremental_archive_entry
* entry
= (*p
)->archive_entry();
702 gold_assert(entry
!= NULL
);
703 (*p
)->set_info_offset(info_offset
);
704 // Member count + unused global symbol count.
707 info_offset
+= (entry
->get_member_count() * 4);
708 // Each global symbol.
709 info_offset
+= (entry
->get_unused_global_symbol_count() * 4);
717 this->set_data_size(info_offset
);
719 // Set the size of the .gnu_incremental_symtab section.
720 inputs
->symtab_section()->set_current_data_size(this->symtab_
->output_count()
721 * sizeof(unsigned int));
723 // Set the size of the .gnu_incremental_relocs section.
724 inputs
->relocs_section()->set_current_data_size(inputs
->get_reloc_count()
727 // Set the size of the .gnu_incremental_got_plt section.
728 Sized_target
<size
, big_endian
>* target
=
729 parameters
->sized_target
<size
, big_endian
>();
730 unsigned int got_count
= target
->got_entry_count();
731 unsigned int plt_count
= target
->plt_entry_count();
732 unsigned int got_plt_size
= 8; // GOT entry count, PLT entry count.
733 got_plt_size
= (got_plt_size
+ got_count
+ 3) & ~3; // GOT type array.
734 got_plt_size
+= got_count
* 4 + plt_count
* 4; // GOT array, PLT array.
735 inputs
->got_plt_section()->set_current_data_size(got_plt_size
);
738 // Write the contents of the .gnu_incremental_inputs and
739 // .gnu_incremental_symtab sections.
741 template<int size
, bool big_endian
>
743 Output_section_incremental_inputs
<size
, big_endian
>::do_write(Output_file
* of
)
745 const Incremental_inputs
* inputs
= this->inputs_
;
746 Stringpool
* strtab
= inputs
->get_stringpool();
748 // Get a view into the .gnu_incremental_inputs section.
749 const off_t off
= this->offset();
750 const off_t oview_size
= this->data_size();
751 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
752 unsigned char* pov
= oview
;
754 // Get a view into the .gnu_incremental_symtab section.
755 const off_t symtab_off
= inputs
->symtab_section()->offset();
756 const off_t symtab_size
= inputs
->symtab_section()->data_size();
757 unsigned char* const symtab_view
= of
->get_output_view(symtab_off
,
760 // Allocate an array of linked list heads for the .gnu_incremental_symtab
761 // section. Each element corresponds to a global symbol in the output
762 // symbol table, and points to the head of the linked list that threads
763 // through the object file input entries. The value of each element
764 // is the section-relative offset to a global symbol entry in a
765 // supplemental information block.
766 unsigned int global_sym_count
= this->symtab_
->output_count();
767 unsigned int* global_syms
= new unsigned int[global_sym_count
];
768 memset(global_syms
, 0, global_sym_count
* sizeof(unsigned int));
770 // Write the section header.
771 Stringpool::Key command_line_key
= inputs
->command_line_key();
772 pov
= this->write_header(pov
, inputs
->input_file_count(),
773 strtab
->get_offset_from_key(command_line_key
));
775 // Write the list of input files.
776 pov
= this->write_input_files(oview
, pov
, strtab
);
778 // Write the supplemental information blocks for each input file.
779 pov
= this->write_info_blocks(oview
, pov
, strtab
, global_syms
,
782 gold_assert(pov
- oview
== oview_size
);
784 // Write the .gnu_incremental_symtab section.
785 gold_assert(global_sym_count
* 4 == symtab_size
);
786 this->write_symtab(symtab_view
, global_syms
, global_sym_count
);
788 delete[] global_syms
;
790 // Write the .gnu_incremental_got_plt section.
791 const off_t got_plt_off
= inputs
->got_plt_section()->offset();
792 const off_t got_plt_size
= inputs
->got_plt_section()->data_size();
793 unsigned char* const got_plt_view
= of
->get_output_view(got_plt_off
,
795 this->write_got_plt(got_plt_view
, got_plt_size
);
797 of
->write_output_view(off
, oview_size
, oview
);
798 of
->write_output_view(symtab_off
, symtab_size
, symtab_view
);
799 of
->write_output_view(got_plt_off
, got_plt_size
, got_plt_view
);
802 // Write the section header: version, input file count, offset of command line
803 // in the string table, and 4 bytes of padding.
805 template<int size
, bool big_endian
>
807 Output_section_incremental_inputs
<size
, big_endian
>::write_header(
809 unsigned int input_file_count
,
810 section_offset_type command_line_offset
)
812 Swap32::writeval(pov
, INCREMENTAL_LINK_VERSION
);
813 Swap32::writeval(pov
+ 4, input_file_count
);
814 Swap32::writeval(pov
+ 8, command_line_offset
);
815 Swap32::writeval(pov
+ 12, 0);
816 return pov
+ this->header_size
;
819 // Write the input file entries.
821 template<int size
, bool big_endian
>
823 Output_section_incremental_inputs
<size
, big_endian
>::write_input_files(
824 unsigned char* oview
,
828 const Incremental_inputs
* inputs
= this->inputs_
;
830 for (Incremental_inputs::Input_list::const_iterator p
=
831 inputs
->input_files().begin();
832 p
!= inputs
->input_files().end();
835 gold_assert(static_cast<unsigned int>(pov
- oview
) == (*p
)->get_offset());
836 section_offset_type filename_offset
=
837 strtab
->get_offset_from_key((*p
)->get_filename_key());
838 const Timespec
& mtime
= (*p
)->get_mtime();
839 Swap32::writeval(pov
, filename_offset
);
840 Swap32::writeval(pov
+ 4, (*p
)->get_info_offset());
841 Swap64::writeval(pov
+ 8, mtime
.seconds
);
842 Swap32::writeval(pov
+ 16, mtime
.nanoseconds
);
843 Swap16::writeval(pov
+ 20, (*p
)->type());
844 Swap16::writeval(pov
+ 22, 0);
845 pov
+= this->input_entry_size
;
850 // Write the supplemental information blocks.
852 template<int size
, bool big_endian
>
854 Output_section_incremental_inputs
<size
, big_endian
>::write_info_blocks(
855 unsigned char* oview
,
858 unsigned int* global_syms
,
859 unsigned int global_sym_count
)
861 const Incremental_inputs
* inputs
= this->inputs_
;
862 unsigned int first_global_index
= this->symtab_
->first_global_index();
864 for (Incremental_inputs::Input_list::const_iterator p
=
865 inputs
->input_files().begin();
866 p
!= inputs
->input_files().end();
869 switch ((*p
)->type())
871 case INCREMENTAL_INPUT_SCRIPT
:
873 gold_assert(static_cast<unsigned int>(pov
- oview
)
874 == (*p
)->get_info_offset());
875 Incremental_script_entry
* entry
= (*p
)->script_entry();
876 gold_assert(entry
!= NULL
);
878 // Write the object count.
879 unsigned int nobjects
= entry
->get_object_count();
880 Swap32::writeval(pov
, nobjects
);
883 // For each object, write the offset to its input file entry.
884 for (unsigned int i
= 0; i
< nobjects
; ++i
)
886 Incremental_input_entry
* obj
= entry
->get_object(i
);
887 Swap32::writeval(pov
, obj
->get_offset());
893 case INCREMENTAL_INPUT_OBJECT
:
894 case INCREMENTAL_INPUT_ARCHIVE_MEMBER
:
896 gold_assert(static_cast<unsigned int>(pov
- oview
)
897 == (*p
)->get_info_offset());
898 Incremental_object_entry
* entry
= (*p
)->object_entry();
899 gold_assert(entry
!= NULL
);
900 const Object
* obj
= entry
->object();
901 const Object::Symbols
* syms
= obj
->get_global_symbols();
902 // Write the input section count and global symbol count.
903 unsigned int nsections
= entry
->get_input_section_count();
904 unsigned int nsyms
= syms
->size();
905 Swap32::writeval(pov
, nsections
);
906 Swap32::writeval(pov
+ 4, nsyms
);
909 // For each input section, write the name, output section index,
910 // offset within output section, and input section size.
911 for (unsigned int i
= 0; i
< nsections
; i
++)
913 Stringpool::Key key
= entry
->get_input_section_name_key(i
);
914 off_t name_offset
= 0;
916 name_offset
= strtab
->get_offset_from_key(key
);
918 off_t out_offset
= 0;
920 Output_section
* os
= obj
->output_section(i
);
923 out_shndx
= os
->out_shndx();
924 out_offset
= obj
->output_section_offset(i
);
925 sh_size
= entry
->get_input_section_size(i
);
927 Swap32::writeval(pov
, name_offset
);
928 Swap32::writeval(pov
+ 4, out_shndx
);
929 Swap::writeval(pov
+ 8, out_offset
);
930 Swap::writeval(pov
+ 8 + sizeof_addr
, sh_size
);
931 pov
+= 8 + 2 * sizeof_addr
;
934 // For each global symbol, write its associated relocations,
935 // add it to the linked list of globals, then write the
936 // supplemental information: global symbol table index,
937 // linked list chain pointer, relocation count, and offset
938 // to the relocations.
939 for (unsigned int i
= 0; i
< nsyms
; i
++)
941 const Symbol
* sym
= (*syms
)[i
];
942 if (sym
->is_forwarder())
943 sym
= this->symtab_
->resolve_forwards(sym
);
944 unsigned int symtab_index
= sym
->symtab_index();
945 unsigned int chain
= 0;
946 unsigned int first_reloc
= 0;
947 unsigned int nrelocs
= obj
->get_incremental_reloc_count(i
);
950 gold_assert(symtab_index
!= -1U
951 && (symtab_index
- first_global_index
952 < global_sym_count
));
953 first_reloc
= obj
->get_incremental_reloc_base(i
);
954 chain
= global_syms
[symtab_index
- first_global_index
];
955 global_syms
[symtab_index
- first_global_index
] =
958 Swap32::writeval(pov
, symtab_index
);
959 Swap32::writeval(pov
+ 4, chain
);
960 Swap32::writeval(pov
+ 8, nrelocs
);
961 Swap32::writeval(pov
+ 12, first_reloc
* 3 * sizeof_addr
);
967 case INCREMENTAL_INPUT_SHARED_LIBRARY
:
969 gold_assert(static_cast<unsigned int>(pov
- oview
)
970 == (*p
)->get_info_offset());
971 Incremental_object_entry
* entry
= (*p
)->object_entry();
972 gold_assert(entry
!= NULL
);
973 const Object
* obj
= entry
->object();
974 const Object::Symbols
* syms
= obj
->get_global_symbols();
976 // Write the global symbol count.
977 unsigned int nsyms
= syms
!= NULL
? syms
->size() : 0;
978 Swap32::writeval(pov
, nsyms
);
981 // For each global symbol, write the global symbol table index.
982 for (unsigned int i
= 0; i
< nsyms
; i
++)
984 const Symbol
* sym
= (*syms
)[i
];
985 Swap32::writeval(pov
, sym
->symtab_index());
991 case INCREMENTAL_INPUT_ARCHIVE
:
993 gold_assert(static_cast<unsigned int>(pov
- oview
)
994 == (*p
)->get_info_offset());
995 Incremental_archive_entry
* entry
= (*p
)->archive_entry();
996 gold_assert(entry
!= NULL
);
998 // Write the member count and unused global symbol count.
999 unsigned int nmembers
= entry
->get_member_count();
1000 unsigned int nsyms
= entry
->get_unused_global_symbol_count();
1001 Swap32::writeval(pov
, nmembers
);
1002 Swap32::writeval(pov
+ 4, nsyms
);
1005 // For each member, write the offset to its input file entry.
1006 for (unsigned int i
= 0; i
< nmembers
; ++i
)
1008 Incremental_object_entry
* member
= entry
->get_member(i
);
1009 Swap32::writeval(pov
, member
->get_offset());
1013 // For each global symbol, write the name offset.
1014 for (unsigned int i
= 0; i
< nsyms
; ++i
)
1016 Stringpool::Key key
= entry
->get_unused_global_symbol(i
);
1017 Swap32::writeval(pov
, strtab
->get_offset_from_key(key
));
1030 // Write the contents of the .gnu_incremental_symtab section.
1032 template<int size
, bool big_endian
>
1034 Output_section_incremental_inputs
<size
, big_endian
>::write_symtab(
1036 unsigned int* global_syms
,
1037 unsigned int global_sym_count
)
1039 for (unsigned int i
= 0; i
< global_sym_count
; ++i
)
1041 Swap32::writeval(pov
, global_syms
[i
]);
1046 // This struct holds the view information needed to write the
1047 // .gnu_incremental_got_plt section.
1049 struct Got_plt_view_info
1051 // Start of the GOT type array in the output view.
1052 unsigned char* got_type_p
;
1053 // Start of the GOT descriptor array in the output view.
1054 unsigned char* got_desc_p
;
1055 // Start of the PLT descriptor array in the output view.
1056 unsigned char* plt_desc_p
;
1057 // Number of GOT entries.
1058 unsigned int got_count
;
1059 // Number of PLT entries.
1060 unsigned int plt_count
;
1061 // Offset of the first non-reserved PLT entry (this is a target-dependent value).
1062 unsigned int first_plt_entry_offset
;
1063 // Size of a PLT entry (this is a target-dependent value).
1064 unsigned int plt_entry_size
;
1065 // Value to write in the GOT descriptor array. For global symbols,
1066 // this is the global symbol table index; for local symbols, it is
1067 // the offset of the input file entry in the .gnu_incremental_inputs
1069 unsigned int got_descriptor
;
1072 // Functor class for processing a GOT offset list for local symbols.
1073 // Writes the GOT type and symbol index into the GOT type and descriptor
1074 // arrays in the output section.
1076 template<int size
, bool big_endian
>
1077 class Local_got_offset_visitor
1080 Local_got_offset_visitor(struct Got_plt_view_info
& info
)
1085 operator()(unsigned int got_type
, unsigned int got_offset
)
1087 unsigned int got_index
= got_offset
/ this->got_entry_size_
;
1088 gold_assert(got_index
< this->info_
.got_count
);
1089 // We can only handle GOT entry types in the range 0..0x7e
1090 // because we use a byte array to store them, and we use the
1091 // high bit to flag a local symbol.
1092 gold_assert(got_type
< 0x7f);
1093 this->info_
.got_type_p
[got_index
] = got_type
| 0x80;
1094 unsigned char* pov
= this->info_
.got_desc_p
+ got_index
* 4;
1095 elfcpp::Swap
<32, big_endian
>::writeval(pov
, this->info_
.got_descriptor
);
1099 static const unsigned int got_entry_size_
= size
/ 8;
1100 struct Got_plt_view_info
& info_
;
1103 // Functor class for processing a GOT offset list. Writes the GOT type
1104 // and symbol index into the GOT type and descriptor arrays in the output
1107 template<int size
, bool big_endian
>
1108 class Global_got_offset_visitor
1111 Global_got_offset_visitor(struct Got_plt_view_info
& info
)
1116 operator()(unsigned int got_type
, unsigned int got_offset
)
1118 unsigned int got_index
= got_offset
/ this->got_entry_size_
;
1119 gold_assert(got_index
< this->info_
.got_count
);
1120 // We can only handle GOT entry types in the range 0..0x7e
1121 // because we use a byte array to store them, and we use the
1122 // high bit to flag a local symbol.
1123 gold_assert(got_type
< 0x7f);
1124 this->info_
.got_type_p
[got_index
] = got_type
;
1125 unsigned char* pov
= this->info_
.got_desc_p
+ got_index
* 4;
1126 elfcpp::Swap
<32, big_endian
>::writeval(pov
, this->info_
.got_descriptor
);
1130 static const unsigned int got_entry_size_
= size
/ 8;
1131 struct Got_plt_view_info
& info_
;
1134 // Functor class for processing the global symbol table. Processes the
1135 // GOT offset list for the symbol, and writes the symbol table index
1136 // into the PLT descriptor array in the output section.
1138 template<int size
, bool big_endian
>
1139 class Global_symbol_visitor_got_plt
1142 Global_symbol_visitor_got_plt(struct Got_plt_view_info
& info
)
1147 operator()(const Sized_symbol
<size
>* sym
)
1149 typedef Global_got_offset_visitor
<size
, big_endian
> Got_visitor
;
1150 const Got_offset_list
* got_offsets
= sym
->got_offset_list();
1151 if (got_offsets
!= NULL
)
1153 info_
.got_descriptor
= sym
->symtab_index();
1154 got_offsets
->for_all_got_offsets(Got_visitor(info_
));
1156 if (sym
->has_plt_offset())
1158 unsigned int plt_index
=
1159 ((sym
->plt_offset() - this->info_
.first_plt_entry_offset
)
1160 / this->info_
.plt_entry_size
);
1161 gold_assert(plt_index
< this->info_
.plt_count
);
1162 unsigned char* pov
= this->info_
.plt_desc_p
+ plt_index
* 4;
1163 elfcpp::Swap
<32, big_endian
>::writeval(pov
, sym
->symtab_index());
1168 struct Got_plt_view_info
& info_
;
1171 // Write the contents of the .gnu_incremental_got_plt section.
1173 template<int size
, bool big_endian
>
1175 Output_section_incremental_inputs
<size
, big_endian
>::write_got_plt(
1179 Sized_target
<size
, big_endian
>* target
=
1180 parameters
->sized_target
<size
, big_endian
>();
1182 // Set up the view information for the functors.
1183 struct Got_plt_view_info view_info
;
1184 view_info
.got_count
= target
->got_entry_count();
1185 view_info
.plt_count
= target
->plt_entry_count();
1186 view_info
.first_plt_entry_offset
= target
->first_plt_entry_offset();
1187 view_info
.plt_entry_size
= target
->plt_entry_size();
1188 view_info
.got_type_p
= pov
+ 8;
1189 view_info
.got_desc_p
= (view_info
.got_type_p
1190 + ((view_info
.got_count
+ 3) & ~3));
1191 view_info
.plt_desc_p
= view_info
.got_desc_p
+ view_info
.got_count
* 4;
1193 gold_assert(pov
+ view_size
==
1194 view_info
.plt_desc_p
+ view_info
.plt_count
* 4);
1196 // Write the section header.
1197 Swap32::writeval(pov
, view_info
.got_count
);
1198 Swap32::writeval(pov
+ 4, view_info
.plt_count
);
1200 // Initialize the GOT type array to 0xff (reserved).
1201 memset(view_info
.got_type_p
, 0xff, view_info
.got_count
);
1203 // Write the incremental GOT descriptors for local symbols.
1204 for (Incremental_inputs::Input_list::const_iterator p
=
1205 this->inputs_
->input_files().begin();
1206 p
!= this->inputs_
->input_files().end();
1209 if ((*p
)->type() != INCREMENTAL_INPUT_OBJECT
1210 && (*p
)->type() != INCREMENTAL_INPUT_ARCHIVE_MEMBER
)
1212 Incremental_object_entry
* entry
= (*p
)->object_entry();
1213 gold_assert(entry
!= NULL
);
1214 const Sized_relobj
<size
, big_endian
>* obj
=
1215 static_cast<Sized_relobj
<size
, big_endian
>*>(entry
->object());
1216 gold_assert(obj
!= NULL
);
1217 unsigned int nsyms
= obj
->local_symbol_count();
1218 for (unsigned int i
= 0; i
< nsyms
; i
++)
1220 const Got_offset_list
* got_offsets
= obj
->local_got_offset_list(i
);
1221 if (got_offsets
!= NULL
)
1223 typedef Local_got_offset_visitor
<size
, big_endian
> Got_visitor
;
1224 view_info
.got_descriptor
= (*p
)->get_offset();
1225 got_offsets
->for_all_got_offsets(Got_visitor(view_info
));
1230 // Write the incremental GOT and PLT descriptors for global symbols.
1231 typedef Global_symbol_visitor_got_plt
<size
, big_endian
> Symbol_visitor
;
1232 symtab_
->for_all_symbols
<size
, Symbol_visitor
>(Symbol_visitor(view_info
));
1235 // Instantiate the templates we need.
1237 #ifdef HAVE_TARGET_32_LITTLE
1239 class Sized_incremental_binary
<32, false>;
1242 #ifdef HAVE_TARGET_32_BIG
1244 class Sized_incremental_binary
<32, true>;
1247 #ifdef HAVE_TARGET_64_LITTLE
1249 class Sized_incremental_binary
<64, false>;
1252 #ifdef HAVE_TARGET_64_BIG
1254 class Sized_incremental_binary
<64, true>;
1257 } // End namespace gold.