1 // script-sections.cc -- linker script SECTIONS for gold
3 // Copyright (C) 2008-2016 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.
33 #include "parameters.h"
39 #include "script-sections.h"
41 // Support for the SECTIONS clause in linker scripts.
46 // A region of memory.
50 Memory_region(const char* name
, size_t namelen
, unsigned int attributes
,
51 Expression
* start
, Expression
* length
)
52 : name_(name
, namelen
),
53 attributes_(attributes
),
62 // Return the name of this region.
65 { return this->name_
; }
67 // Return the start address of this region.
70 { return this->start_
; }
72 // Return the length of this region.
75 { return this->length_
; }
77 // Print the region (when debugging).
81 // Return true if <name,namelen> matches this region.
83 name_match(const char* name
, size_t namelen
)
85 return (this->name_
.length() == namelen
86 && strncmp(this->name_
.c_str(), name
, namelen
) == 0);
90 get_current_address() const
93 script_exp_binary_add(this->start_
,
94 script_exp_integer(this->current_offset_
));
98 set_address(uint64_t addr
, const Symbol_table
* symtab
, const Layout
* layout
)
100 uint64_t start
= this->start_
->eval(symtab
, layout
, false);
101 uint64_t len
= this->length_
->eval(symtab
, layout
, false);
102 if (addr
< start
|| addr
>= start
+ len
)
103 gold_error(_("address 0x%llx is not within region %s"),
104 static_cast<unsigned long long>(addr
),
105 this->name_
.c_str());
106 else if (addr
< start
+ this->current_offset_
)
107 gold_error(_("address 0x%llx moves dot backwards in region %s"),
108 static_cast<unsigned long long>(addr
),
109 this->name_
.c_str());
110 this->current_offset_
= addr
- start
;
114 increment_offset(std::string section_name
, uint64_t amount
,
115 const Symbol_table
* symtab
, const Layout
* layout
)
117 this->current_offset_
+= amount
;
119 if (this->current_offset_
120 > this->length_
->eval(symtab
, layout
, false))
121 gold_error(_("section %s overflows end of region %s"),
122 section_name
.c_str(), this->name_
.c_str());
125 // Returns true iff there is room left in this region
126 // for AMOUNT more bytes of data.
128 has_room_for(const Symbol_table
* symtab
, const Layout
* layout
,
129 uint64_t amount
) const
131 return (this->current_offset_
+ amount
132 < this->length_
->eval(symtab
, layout
, false));
135 // Return true if the provided section flags
136 // are compatible with this region's attributes.
138 attributes_compatible(elfcpp::Elf_Xword flags
, elfcpp::Elf_Xword type
) const;
141 add_section(Output_section_definition
* sec
, bool vma
)
144 this->vma_sections_
.push_back(sec
);
146 this->lma_sections_
.push_back(sec
);
149 typedef std::vector
<Output_section_definition
*> Section_list
;
151 // Return the start of the list of sections
152 // whose VMAs are taken from this region.
153 Section_list::const_iterator
154 get_vma_section_list_start() const
155 { return this->vma_sections_
.begin(); }
157 // Return the start of the list of sections
158 // whose LMAs are taken from this region.
159 Section_list::const_iterator
160 get_lma_section_list_start() const
161 { return this->lma_sections_
.begin(); }
163 // Return the end of the list of sections
164 // whose VMAs are taken from this region.
165 Section_list::const_iterator
166 get_vma_section_list_end() const
167 { return this->vma_sections_
.end(); }
169 // Return the end of the list of sections
170 // whose LMAs are taken from this region.
171 Section_list::const_iterator
172 get_lma_section_list_end() const
173 { return this->lma_sections_
.end(); }
175 Output_section_definition
*
176 get_last_section() const
177 { return this->last_section_
; }
180 set_last_section(Output_section_definition
* sec
)
181 { this->last_section_
= sec
; }
186 unsigned int attributes_
;
189 // The offset to the next free byte in the region.
190 // Note - for compatibility with GNU LD we only maintain one offset
191 // regardless of whether the region is being used for VMA values,
192 // LMA values, or both.
193 uint64_t current_offset_
;
194 // A list of sections whose VMAs are set inside this region.
195 Section_list vma_sections_
;
196 // A list of sections whose LMAs are set inside this region.
197 Section_list lma_sections_
;
198 // The latest section to make use of this region.
199 Output_section_definition
* last_section_
;
202 // Return true if the provided section flags
203 // are compatible with this region's attributes.
206 Memory_region::attributes_compatible(elfcpp::Elf_Xword flags
,
207 elfcpp::Elf_Xword type
) const
209 unsigned int attrs
= this->attributes_
;
211 // No attributes means that this region is not compatible with anything.
218 switch (attrs
& - attrs
)
221 if ((flags
& elfcpp::SHF_EXECINSTR
) == 0)
226 if ((flags
& elfcpp::SHF_WRITE
) == 0)
231 // All sections are presumed readable.
234 case MEM_ALLOCATABLE
:
235 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
239 case MEM_INITIALIZED
:
240 if ((type
& elfcpp::SHT_NOBITS
) != 0)
244 attrs
&= ~ (attrs
& - attrs
);
251 // Print a memory region.
254 Memory_region::print(FILE* f
) const
256 fprintf(f
, " %s", this->name_
.c_str());
258 unsigned int attrs
= this->attributes_
;
264 switch (attrs
& - attrs
)
266 case MEM_EXECUTABLE
: fputc('x', f
); break;
267 case MEM_WRITEABLE
: fputc('w', f
); break;
268 case MEM_READABLE
: fputc('r', f
); break;
269 case MEM_ALLOCATABLE
: fputc('a', f
); break;
270 case MEM_INITIALIZED
: fputc('i', f
); break;
274 attrs
&= ~ (attrs
& - attrs
);
280 fprintf(f
, " : origin = ");
281 this->start_
->print(f
);
282 fprintf(f
, ", length = ");
283 this->length_
->print(f
);
287 // Manage orphan sections. This is intended to be largely compatible
288 // with the GNU linker. The Linux kernel implicitly relies on
289 // something similar to the GNU linker's orphan placement. We
290 // originally used a simpler scheme here, but it caused the kernel
291 // build to fail, and was also rather inefficient.
293 class Orphan_section_placement
296 typedef Script_sections::Elements_iterator Elements_iterator
;
299 Orphan_section_placement();
301 // Handle an output section during initialization of this mapping.
303 output_section_init(const std::string
& name
, Output_section
*,
304 Elements_iterator location
);
306 // Initialize the last location.
308 last_init(Elements_iterator location
);
310 // Set *PWHERE to the address of an iterator pointing to the
311 // location to use for an orphan section. Return true if the
312 // iterator has a value, false otherwise.
314 find_place(Output_section
*, Elements_iterator
** pwhere
);
316 // Update PLACE_LAST_ALLOC.
318 update_last_alloc(Elements_iterator where
);
320 // Return the iterator being used for sections at the very end of
321 // the linker script.
326 // The places that we specifically recognize. This list is copied
327 // from the GNU linker.
344 // The information we keep for a specific place.
347 // The name of sections for this place.
349 // Whether we have a location for this place.
351 // The iterator for this place.
352 Elements_iterator location
;
355 // Initialize one place element.
357 initialize_place(Place_index
, const char*);
360 Place places_
[PLACE_MAX
];
361 // True if this is the first call to output_section_init.
365 // Initialize Orphan_section_placement.
367 Orphan_section_placement::Orphan_section_placement()
370 this->initialize_place(PLACE_TEXT
, ".text");
371 this->initialize_place(PLACE_RODATA
, ".rodata");
372 this->initialize_place(PLACE_DATA
, ".data");
373 this->initialize_place(PLACE_TLS
, NULL
);
374 this->initialize_place(PLACE_TLS_BSS
, NULL
);
375 this->initialize_place(PLACE_BSS
, ".bss");
376 this->initialize_place(PLACE_LAST_ALLOC
, NULL
);
377 this->initialize_place(PLACE_REL
, NULL
);
378 this->initialize_place(PLACE_INTERP
, ".interp");
379 this->initialize_place(PLACE_NONALLOC
, NULL
);
380 this->initialize_place(PLACE_LAST
, NULL
);
383 // Initialize one place element.
386 Orphan_section_placement::initialize_place(Place_index index
, const char* name
)
388 this->places_
[index
].name
= name
;
389 this->places_
[index
].have_location
= false;
392 // While initializing the Orphan_section_placement information, this
393 // is called once for each output section named in the linker script.
394 // If we found an output section during the link, it will be passed in
398 Orphan_section_placement::output_section_init(const std::string
& name
,
400 Elements_iterator location
)
402 bool first_init
= this->first_init_
;
403 this->first_init_
= false;
405 // Remember the last allocated section. Any orphan bss sections
406 // will be placed after it.
408 && (os
->flags() & elfcpp::SHF_ALLOC
) != 0)
410 this->places_
[PLACE_LAST_ALLOC
].location
= location
;
411 this->places_
[PLACE_LAST_ALLOC
].have_location
= true;
414 for (int i
= 0; i
< PLACE_MAX
; ++i
)
416 if (this->places_
[i
].name
!= NULL
&& this->places_
[i
].name
== name
)
418 if (this->places_
[i
].have_location
)
420 // We have already seen a section with this name.
424 this->places_
[i
].location
= location
;
425 this->places_
[i
].have_location
= true;
427 // If we just found the .bss section, restart the search for
428 // an unallocated section. This follows the GNU linker's
431 this->places_
[PLACE_NONALLOC
].have_location
= false;
437 // Relocation sections.
438 if (!this->places_
[PLACE_REL
].have_location
440 && (os
->type() == elfcpp::SHT_REL
|| os
->type() == elfcpp::SHT_RELA
)
441 && (os
->flags() & elfcpp::SHF_ALLOC
) != 0)
443 this->places_
[PLACE_REL
].location
= location
;
444 this->places_
[PLACE_REL
].have_location
= true;
447 // We find the location for unallocated sections by finding the
448 // first debugging or comment section after the BSS section (if
450 if (!this->places_
[PLACE_NONALLOC
].have_location
451 && (name
== ".comment" || Layout::is_debug_info_section(name
.c_str())))
453 // We add orphan sections after the location in PLACES_. We
454 // want to store unallocated sections before LOCATION. If this
455 // is the very first section, we can't use it.
459 this->places_
[PLACE_NONALLOC
].location
= location
;
460 this->places_
[PLACE_NONALLOC
].have_location
= true;
465 // Initialize the last location.
468 Orphan_section_placement::last_init(Elements_iterator location
)
470 this->places_
[PLACE_LAST
].location
= location
;
471 this->places_
[PLACE_LAST
].have_location
= true;
474 // Set *PWHERE to the address of an iterator pointing to the location
475 // to use for an orphan section. Return true if the iterator has a
476 // value, false otherwise.
479 Orphan_section_placement::find_place(Output_section
* os
,
480 Elements_iterator
** pwhere
)
482 // Figure out where OS should go. This is based on the GNU linker
483 // code. FIXME: The GNU linker handles small data sections
484 // specially, but we don't.
485 elfcpp::Elf_Word type
= os
->type();
486 elfcpp::Elf_Xword flags
= os
->flags();
488 if ((flags
& elfcpp::SHF_ALLOC
) == 0
489 && !Layout::is_debug_info_section(os
->name()))
490 index
= PLACE_NONALLOC
;
491 else if ((flags
& elfcpp::SHF_ALLOC
) == 0)
493 else if (type
== elfcpp::SHT_NOTE
)
494 index
= PLACE_INTERP
;
495 else if ((flags
& elfcpp::SHF_TLS
) != 0)
497 if (type
== elfcpp::SHT_NOBITS
)
498 index
= PLACE_TLS_BSS
;
502 else if (type
== elfcpp::SHT_NOBITS
)
504 else if ((flags
& elfcpp::SHF_WRITE
) != 0)
506 else if (type
== elfcpp::SHT_REL
|| type
== elfcpp::SHT_RELA
)
508 else if ((flags
& elfcpp::SHF_EXECINSTR
) == 0)
509 index
= PLACE_RODATA
;
513 // If we don't have a location yet, try to find one based on a
514 // plausible ordering of sections.
515 if (!this->places_
[index
].have_location
)
527 follow
= PLACE_RODATA
;
528 if (!this->places_
[PLACE_RODATA
].have_location
)
532 follow
= PLACE_LAST_ALLOC
;
545 if (!this->places_
[PLACE_TLS
].have_location
)
549 if (follow
!= PLACE_MAX
&& this->places_
[follow
].have_location
)
551 // Set the location of INDEX to the location of FOLLOW. The
552 // location of INDEX will then be incremented by the caller,
553 // so anything in INDEX will continue to be after anything
555 this->places_
[index
].location
= this->places_
[follow
].location
;
556 this->places_
[index
].have_location
= true;
560 *pwhere
= &this->places_
[index
].location
;
561 bool ret
= this->places_
[index
].have_location
;
563 // The caller will set the location.
564 this->places_
[index
].have_location
= true;
569 // Update PLACE_LAST_ALLOC.
571 Orphan_section_placement::update_last_alloc(Elements_iterator elem
)
573 Elements_iterator prev
= elem
;
575 if (this->places_
[PLACE_LAST_ALLOC
].have_location
576 && this->places_
[PLACE_LAST_ALLOC
].location
== prev
)
578 this->places_
[PLACE_LAST_ALLOC
].have_location
= true;
579 this->places_
[PLACE_LAST_ALLOC
].location
= elem
;
583 // Return the iterator being used for sections at the very end of the
586 Orphan_section_placement::Elements_iterator
587 Orphan_section_placement::last_place() const
589 gold_assert(this->places_
[PLACE_LAST
].have_location
);
590 return this->places_
[PLACE_LAST
].location
;
593 // An element in a SECTIONS clause.
595 class Sections_element
601 virtual ~Sections_element()
604 // Return whether an output section is relro.
609 // Record that an output section is relro.
614 // Create any required output sections. The only real
615 // implementation is in Output_section_definition.
617 create_sections(Layout
*)
620 // Add any symbol being defined to the symbol table.
622 add_symbols_to_table(Symbol_table
*)
625 // Finalize symbols and check assertions.
627 finalize_symbols(Symbol_table
*, const Layout
*, uint64_t*)
630 // Return the output section name to use for an input file name and
631 // section name. This only real implementation is in
632 // Output_section_definition.
634 output_section_name(const char*, const char*, Output_section
***,
635 Script_sections::Section_type
*, bool*)
638 // Initialize OSP with an output section.
640 orphan_section_init(Orphan_section_placement
*,
641 Script_sections::Elements_iterator
)
644 // Set section addresses. This includes applying assignments if the
645 // expression is an absolute value.
647 set_section_addresses(Symbol_table
*, Layout
*, uint64_t*, uint64_t*,
651 // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
652 // this section is constrained, and the input sections do not match,
653 // return the constraint, and set *POSD.
654 virtual Section_constraint
655 check_constraint(Output_section_definition
**)
656 { return CONSTRAINT_NONE
; }
658 // See if this is the alternate output section for a constrained
659 // output section. If it is, transfer the Output_section and return
660 // true. Otherwise return false.
662 alternate_constraint(Output_section_definition
*, Section_constraint
)
665 // Get the list of segments to use for an allocated section when
666 // using a PHDRS clause. If this is an allocated section, return
667 // the Output_section, and set *PHDRS_LIST (the first parameter) to
668 // the list of PHDRS to which it should be attached. If the PHDRS
669 // were not specified, don't change *PHDRS_LIST. When not returning
670 // NULL, set *ORPHAN (the second parameter) according to whether
671 // this is an orphan section--one that is not mentioned in the
673 virtual Output_section
*
674 allocate_to_segment(String_list
**, bool*)
677 // Look for an output section by name and return the address, the
678 // load address, the alignment, and the size. This is used when an
679 // expression refers to an output section which was not actually
680 // created. This returns true if the section was found, false
681 // otherwise. The only real definition is for
682 // Output_section_definition.
684 get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*,
688 // Return the associated Output_section if there is one.
689 virtual Output_section
*
690 get_output_section() const
693 // Set the section's memory regions.
695 set_memory_region(Memory_region
*, bool)
696 { gold_error(_("Attempt to set a memory region for a non-output section")); }
698 // Print the element for debugging purposes.
700 print(FILE* f
) const = 0;
703 // An assignment in a SECTIONS clause outside of an output section.
705 class Sections_element_assignment
: public Sections_element
708 Sections_element_assignment(const char* name
, size_t namelen
,
709 Expression
* val
, bool provide
, bool hidden
)
710 : assignment_(name
, namelen
, false, val
, provide
, hidden
)
713 // Add the symbol to the symbol table.
715 add_symbols_to_table(Symbol_table
* symtab
)
716 { this->assignment_
.add_to_table(symtab
); }
718 // Finalize the symbol.
720 finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
,
723 this->assignment_
.finalize_with_dot(symtab
, layout
, *dot_value
, NULL
);
726 // Set the section address. There is no section here, but if the
727 // value is absolute, we set the symbol. This permits us to use
728 // absolute symbols when setting dot.
730 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
,
731 uint64_t* dot_value
, uint64_t*, uint64_t*)
733 this->assignment_
.set_if_absolute(symtab
, layout
, true, *dot_value
, NULL
);
736 // Print for debugging.
741 this->assignment_
.print(f
);
745 Symbol_assignment assignment_
;
748 // An assignment to the dot symbol in a SECTIONS clause outside of an
751 class Sections_element_dot_assignment
: public Sections_element
754 Sections_element_dot_assignment(Expression
* val
)
758 // Finalize the symbol.
760 finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
,
763 // We ignore the section of the result because outside of an
764 // output section definition the dot symbol is always considered
766 *dot_value
= this->val_
->eval_with_dot(symtab
, layout
, true, *dot_value
,
767 NULL
, NULL
, NULL
, false);
770 // Update the dot symbol while setting section addresses.
772 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
,
773 uint64_t* dot_value
, uint64_t* dot_alignment
,
774 uint64_t* load_address
)
776 *dot_value
= this->val_
->eval_with_dot(symtab
, layout
, false, *dot_value
,
777 NULL
, NULL
, dot_alignment
, false);
778 *load_address
= *dot_value
;
781 // Print for debugging.
786 this->val_
->print(f
);
794 // An assertion in a SECTIONS clause outside of an output section.
796 class Sections_element_assertion
: public Sections_element
799 Sections_element_assertion(Expression
* check
, const char* message
,
801 : assertion_(check
, message
, messagelen
)
804 // Check the assertion.
806 finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
, uint64_t*)
807 { this->assertion_
.check(symtab
, layout
); }
809 // Print for debugging.
814 this->assertion_
.print(f
);
818 Script_assertion assertion_
;
821 // An element in an output section in a SECTIONS clause.
823 class Output_section_element
826 // A list of input sections.
827 typedef std::list
<Output_section::Input_section
> Input_section_list
;
829 Output_section_element()
832 virtual ~Output_section_element()
835 // Return whether this element requires an output section to exist.
837 needs_output_section() const
840 // Add any symbol being defined to the symbol table.
842 add_symbols_to_table(Symbol_table
*)
845 // Finalize symbols and check assertions.
847 finalize_symbols(Symbol_table
*, const Layout
*, uint64_t*, Output_section
**)
850 // Return whether this element matches FILE_NAME and SECTION_NAME.
851 // The only real implementation is in Output_section_element_input.
853 match_name(const char*, const char*, bool *) const
856 // Set section addresses. This includes applying assignments if the
857 // expression is an absolute value.
859 set_section_addresses(Symbol_table
*, Layout
*, Output_section
*, uint64_t,
860 uint64_t*, uint64_t*, Output_section
**, std::string
*,
864 // Print the element for debugging purposes.
866 print(FILE* f
) const = 0;
869 // Return a fill string that is LENGTH bytes long, filling it with
872 get_fill_string(const std::string
* fill
, section_size_type length
) const;
876 Output_section_element::get_fill_string(const std::string
* fill
,
877 section_size_type length
) const
879 std::string this_fill
;
880 this_fill
.reserve(length
);
881 while (this_fill
.length() + fill
->length() <= length
)
883 if (this_fill
.length() < length
)
884 this_fill
.append(*fill
, 0, length
- this_fill
.length());
888 // A symbol assignment in an output section.
890 class Output_section_element_assignment
: public Output_section_element
893 Output_section_element_assignment(const char* name
, size_t namelen
,
894 Expression
* val
, bool provide
,
896 : assignment_(name
, namelen
, false, val
, provide
, hidden
)
899 // Add the symbol to the symbol table.
901 add_symbols_to_table(Symbol_table
* symtab
)
902 { this->assignment_
.add_to_table(symtab
); }
904 // Finalize the symbol.
906 finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
,
907 uint64_t* dot_value
, Output_section
** dot_section
)
909 this->assignment_
.finalize_with_dot(symtab
, layout
, *dot_value
,
913 // Set the section address. There is no section here, but if the
914 // value is absolute, we set the symbol. This permits us to use
915 // absolute symbols when setting dot.
917 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
, Output_section
*,
918 uint64_t, uint64_t* dot_value
, uint64_t*,
919 Output_section
** dot_section
, std::string
*,
922 this->assignment_
.set_if_absolute(symtab
, layout
, true, *dot_value
,
926 // Print for debugging.
931 this->assignment_
.print(f
);
935 Symbol_assignment assignment_
;
938 // An assignment to the dot symbol in an output section.
940 class Output_section_element_dot_assignment
: public Output_section_element
943 Output_section_element_dot_assignment(Expression
* val
)
947 // An assignment to dot within an output section is enough to force
948 // the output section to exist.
950 needs_output_section() const
953 // Finalize the symbol.
955 finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
,
956 uint64_t* dot_value
, Output_section
** dot_section
)
958 *dot_value
= this->val_
->eval_with_dot(symtab
, layout
, true, *dot_value
,
959 *dot_section
, dot_section
, NULL
,
963 // Update the dot symbol while setting section addresses.
965 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
, Output_section
*,
966 uint64_t, uint64_t* dot_value
, uint64_t*,
967 Output_section
** dot_section
, std::string
*,
968 Input_section_list
*);
970 // Print for debugging.
975 this->val_
->print(f
);
983 // Update the dot symbol while setting section addresses.
986 Output_section_element_dot_assignment::set_section_addresses(
987 Symbol_table
* symtab
,
989 Output_section
* output_section
,
992 uint64_t* dot_alignment
,
993 Output_section
** dot_section
,
997 uint64_t next_dot
= this->val_
->eval_with_dot(symtab
, layout
, false,
998 *dot_value
, *dot_section
,
999 dot_section
, dot_alignment
,
1001 if (next_dot
< *dot_value
)
1002 gold_error(_("dot may not move backward"));
1003 if (next_dot
> *dot_value
&& output_section
!= NULL
)
1005 section_size_type length
= convert_to_section_size_type(next_dot
1007 Output_section_data
* posd
;
1009 posd
= new Output_data_zero_fill(length
, 0);
1012 std::string this_fill
= this->get_fill_string(fill
, length
);
1013 posd
= new Output_data_const(this_fill
, 0);
1015 output_section
->add_output_section_data(posd
);
1016 layout
->new_output_section_data_from_script(posd
);
1018 *dot_value
= next_dot
;
1021 // An assertion in an output section.
1023 class Output_section_element_assertion
: public Output_section_element
1026 Output_section_element_assertion(Expression
* check
, const char* message
,
1028 : assertion_(check
, message
, messagelen
)
1032 print(FILE* f
) const
1035 this->assertion_
.print(f
);
1039 Script_assertion assertion_
;
1042 // We use a special instance of Output_section_data to handle BYTE,
1043 // SHORT, etc. This permits forward references to symbols in the
1046 class Output_data_expression
: public Output_section_data
1049 Output_data_expression(int size
, bool is_signed
, Expression
* val
,
1050 const Symbol_table
* symtab
, const Layout
* layout
,
1051 uint64_t dot_value
, Output_section
* dot_section
)
1052 : Output_section_data(size
, 0, true),
1053 is_signed_(is_signed
), val_(val
), symtab_(symtab
),
1054 layout_(layout
), dot_value_(dot_value
), dot_section_(dot_section
)
1058 // Write the data to the output file.
1060 do_write(Output_file
*);
1062 // Write the data to a buffer.
1064 do_write_to_buffer(unsigned char*);
1066 // Write to a map file.
1068 do_print_to_mapfile(Mapfile
* mapfile
) const
1069 { mapfile
->print_output_data(this, _("** expression")); }
1072 template<bool big_endian
>
1074 endian_write_to_buffer(uint64_t, unsigned char*);
1078 const Symbol_table
* symtab_
;
1079 const Layout
* layout_
;
1080 uint64_t dot_value_
;
1081 Output_section
* dot_section_
;
1084 // Write the data element to the output file.
1087 Output_data_expression::do_write(Output_file
* of
)
1089 unsigned char* view
= of
->get_output_view(this->offset(), this->data_size());
1090 this->write_to_buffer(view
);
1091 of
->write_output_view(this->offset(), this->data_size(), view
);
1094 // Write the data element to a buffer.
1097 Output_data_expression::do_write_to_buffer(unsigned char* buf
)
1099 uint64_t val
= this->val_
->eval_with_dot(this->symtab_
, this->layout_
,
1100 true, this->dot_value_
,
1101 this->dot_section_
, NULL
, NULL
,
1104 if (parameters
->target().is_big_endian())
1105 this->endian_write_to_buffer
<true>(val
, buf
);
1107 this->endian_write_to_buffer
<false>(val
, buf
);
1110 template<bool big_endian
>
1112 Output_data_expression::endian_write_to_buffer(uint64_t val
,
1115 switch (this->data_size())
1118 elfcpp::Swap_unaligned
<8, big_endian
>::writeval(buf
, val
);
1121 elfcpp::Swap_unaligned
<16, big_endian
>::writeval(buf
, val
);
1124 elfcpp::Swap_unaligned
<32, big_endian
>::writeval(buf
, val
);
1127 if (parameters
->target().get_size() == 32)
1130 if (this->is_signed_
&& (val
& 0x80000000) != 0)
1131 val
|= 0xffffffff00000000LL
;
1133 elfcpp::Swap_unaligned
<64, big_endian
>::writeval(buf
, val
);
1140 // A data item in an output section.
1142 class Output_section_element_data
: public Output_section_element
1145 Output_section_element_data(int size
, bool is_signed
, Expression
* val
)
1146 : size_(size
), is_signed_(is_signed
), val_(val
)
1149 // If there is a data item, then we must create an output section.
1151 needs_output_section() const
1154 // Finalize symbols--we just need to update dot.
1156 finalize_symbols(Symbol_table
*, const Layout
*, uint64_t* dot_value
,
1158 { *dot_value
+= this->size_
; }
1160 // Store the value in the section.
1162 set_section_addresses(Symbol_table
*, Layout
*, Output_section
*, uint64_t,
1163 uint64_t* dot_value
, uint64_t*, Output_section
**,
1164 std::string
*, Input_section_list
*);
1166 // Print for debugging.
1171 // The size in bytes.
1173 // Whether the value is signed.
1179 // Store the value in the section.
1182 Output_section_element_data::set_section_addresses(
1183 Symbol_table
* symtab
,
1187 uint64_t* dot_value
,
1189 Output_section
** dot_section
,
1191 Input_section_list
*)
1193 gold_assert(os
!= NULL
);
1194 Output_data_expression
* expression
=
1195 new Output_data_expression(this->size_
, this->is_signed_
, this->val_
,
1196 symtab
, layout
, *dot_value
, *dot_section
);
1197 os
->add_output_section_data(expression
);
1198 layout
->new_output_section_data_from_script(expression
);
1199 *dot_value
+= this->size_
;
1202 // Print for debugging.
1205 Output_section_element_data::print(FILE* f
) const
1208 switch (this->size_
)
1220 if (this->is_signed_
)
1228 fprintf(f
, " %s(", s
);
1229 this->val_
->print(f
);
1233 // A fill value setting in an output section.
1235 class Output_section_element_fill
: public Output_section_element
1238 Output_section_element_fill(Expression
* val
)
1242 // Update the fill value while setting section addresses.
1244 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
, Output_section
*,
1245 uint64_t, uint64_t* dot_value
, uint64_t*,
1246 Output_section
** dot_section
,
1247 std::string
* fill
, Input_section_list
*)
1249 Output_section
* fill_section
;
1250 uint64_t fill_val
= this->val_
->eval_with_dot(symtab
, layout
, false,
1251 *dot_value
, *dot_section
,
1252 &fill_section
, NULL
, false);
1253 if (fill_section
!= NULL
)
1254 gold_warning(_("fill value is not absolute"));
1255 // FIXME: The GNU linker supports fill values of arbitrary length.
1256 unsigned char fill_buff
[4];
1257 elfcpp::Swap_unaligned
<32, true>::writeval(fill_buff
, fill_val
);
1258 fill
->assign(reinterpret_cast<char*>(fill_buff
), 4);
1261 // Print for debugging.
1263 print(FILE* f
) const
1265 fprintf(f
, " FILL(");
1266 this->val_
->print(f
);
1271 // The new fill value.
1275 // An input section specification in an output section
1277 class Output_section_element_input
: public Output_section_element
1280 Output_section_element_input(const Input_section_spec
* spec
, bool keep
);
1282 // Finalize symbols--just update the value of the dot symbol.
1284 finalize_symbols(Symbol_table
*, const Layout
*, uint64_t* dot_value
,
1285 Output_section
** dot_section
)
1287 *dot_value
= this->final_dot_value_
;
1288 *dot_section
= this->final_dot_section_
;
1291 // See whether we match FILE_NAME and SECTION_NAME as an input section.
1292 // If we do then also indicate whether the section should be KEPT.
1294 match_name(const char* file_name
, const char* section_name
, bool* keep
) const;
1296 // Set the section address.
1298 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
, Output_section
*,
1299 uint64_t subalign
, uint64_t* dot_value
, uint64_t*,
1300 Output_section
**, std::string
* fill
,
1301 Input_section_list
*);
1303 // Print for debugging.
1305 print(FILE* f
) const;
1308 // An input section pattern.
1309 struct Input_section_pattern
1311 std::string pattern
;
1312 bool pattern_is_wildcard
;
1315 Input_section_pattern(const char* patterna
, size_t patternlena
,
1316 Sort_wildcard sorta
)
1317 : pattern(patterna
, patternlena
),
1318 pattern_is_wildcard(is_wildcard_string(this->pattern
.c_str())),
1323 typedef std::vector
<Input_section_pattern
> Input_section_patterns
;
1325 // Filename_exclusions is a pair of filename pattern and a bool
1326 // indicating whether the filename is a wildcard.
1327 typedef std::vector
<std::pair
<std::string
, bool> > Filename_exclusions
;
1329 // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN
1330 // indicates whether this is a wildcard pattern.
1332 match(const char* string
, const char* pattern
, bool is_wildcard_pattern
)
1334 return (is_wildcard_pattern
1335 ? fnmatch(pattern
, string
, 0) == 0
1336 : strcmp(string
, pattern
) == 0);
1339 // See if we match a file name.
1341 match_file_name(const char* file_name
) const;
1343 // The file name pattern. If this is the empty string, we match all
1345 std::string filename_pattern_
;
1346 // Whether the file name pattern is a wildcard.
1347 bool filename_is_wildcard_
;
1348 // How the file names should be sorted. This may only be
1349 // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME.
1350 Sort_wildcard filename_sort_
;
1351 // The list of file names to exclude.
1352 Filename_exclusions filename_exclusions_
;
1353 // The list of input section patterns.
1354 Input_section_patterns input_section_patterns_
;
1355 // Whether to keep this section when garbage collecting.
1357 // The value of dot after including all matching sections.
1358 uint64_t final_dot_value_
;
1359 // The section where dot is defined after including all matching
1361 Output_section
* final_dot_section_
;
1364 // Construct Output_section_element_input. The parser records strings
1365 // as pointers into a copy of the script file, which will go away when
1366 // parsing is complete. We make sure they are in std::string objects.
1368 Output_section_element_input::Output_section_element_input(
1369 const Input_section_spec
* spec
,
1371 : filename_pattern_(),
1372 filename_is_wildcard_(false),
1373 filename_sort_(spec
->file
.sort
),
1374 filename_exclusions_(),
1375 input_section_patterns_(),
1377 final_dot_value_(0),
1378 final_dot_section_(NULL
)
1380 // The filename pattern "*" is common, and matches all files. Turn
1381 // it into the empty string.
1382 if (spec
->file
.name
.length
!= 1 || spec
->file
.name
.value
[0] != '*')
1383 this->filename_pattern_
.assign(spec
->file
.name
.value
,
1384 spec
->file
.name
.length
);
1385 this->filename_is_wildcard_
= is_wildcard_string(this->filename_pattern_
.c_str());
1387 if (spec
->input_sections
.exclude
!= NULL
)
1389 for (String_list::const_iterator p
=
1390 spec
->input_sections
.exclude
->begin();
1391 p
!= spec
->input_sections
.exclude
->end();
1394 bool is_wildcard
= is_wildcard_string((*p
).c_str());
1395 this->filename_exclusions_
.push_back(std::make_pair(*p
,
1400 if (spec
->input_sections
.sections
!= NULL
)
1402 Input_section_patterns
& isp(this->input_section_patterns_
);
1403 for (String_sort_list::const_iterator p
=
1404 spec
->input_sections
.sections
->begin();
1405 p
!= spec
->input_sections
.sections
->end();
1407 isp
.push_back(Input_section_pattern(p
->name
.value
, p
->name
.length
,
1412 // See whether we match FILE_NAME.
1415 Output_section_element_input::match_file_name(const char* file_name
) const
1417 if (!this->filename_pattern_
.empty())
1419 // If we were called with no filename, we refuse to match a
1420 // pattern which requires a file name.
1421 if (file_name
== NULL
)
1424 if (!match(file_name
, this->filename_pattern_
.c_str(),
1425 this->filename_is_wildcard_
))
1429 if (file_name
!= NULL
)
1431 // Now we have to see whether FILE_NAME matches one of the
1432 // exclusion patterns, if any.
1433 for (Filename_exclusions::const_iterator p
=
1434 this->filename_exclusions_
.begin();
1435 p
!= this->filename_exclusions_
.end();
1438 if (match(file_name
, p
->first
.c_str(), p
->second
))
1446 // See whether we match FILE_NAME and SECTION_NAME. If we do then
1447 // KEEP indicates whether the section should survive garbage collection.
1450 Output_section_element_input::match_name(const char* file_name
,
1451 const char* section_name
,
1454 if (!this->match_file_name(file_name
))
1457 *keep
= this->keep_
;
1459 // If there are no section name patterns, then we match.
1460 if (this->input_section_patterns_
.empty())
1463 // See whether we match the section name patterns.
1464 for (Input_section_patterns::const_iterator p
=
1465 this->input_section_patterns_
.begin();
1466 p
!= this->input_section_patterns_
.end();
1469 if (match(section_name
, p
->pattern
.c_str(), p
->pattern_is_wildcard
))
1473 // We didn't match any section names, so we didn't match.
1477 // Information we use to sort the input sections.
1479 class Input_section_info
1482 Input_section_info(const Output_section::Input_section
& input_section
)
1483 : input_section_(input_section
), section_name_(),
1484 size_(0), addralign_(1)
1487 // Return the simple input section.
1488 const Output_section::Input_section
&
1489 input_section() const
1490 { return this->input_section_
; }
1492 // Return the object.
1495 { return this->input_section_
.relobj(); }
1497 // Return the section index.
1500 { return this->input_section_
.shndx(); }
1502 // Return the section name.
1504 section_name() const
1505 { return this->section_name_
; }
1507 // Set the section name.
1509 set_section_name(const std::string name
)
1511 if (is_compressed_debug_section(name
.c_str()))
1512 this->section_name_
= corresponding_uncompressed_section_name(name
);
1514 this->section_name_
= name
;
1517 // Return the section size.
1520 { return this->size_
; }
1522 // Set the section size.
1524 set_size(uint64_t size
)
1525 { this->size_
= size
; }
1527 // Return the address alignment.
1530 { return this->addralign_
; }
1532 // Set the address alignment.
1534 set_addralign(uint64_t addralign
)
1535 { this->addralign_
= addralign
; }
1538 // Input section, can be a relaxed section.
1539 Output_section::Input_section input_section_
;
1540 // Name of the section.
1541 std::string section_name_
;
1544 // Address alignment.
1545 uint64_t addralign_
;
1548 // A class to sort the input sections.
1550 class Input_section_sorter
1553 Input_section_sorter(Sort_wildcard filename_sort
, Sort_wildcard section_sort
)
1554 : filename_sort_(filename_sort
), section_sort_(section_sort
)
1558 operator()(const Input_section_info
&, const Input_section_info
&) const;
1561 static unsigned long
1562 get_init_priority(const char*);
1564 Sort_wildcard filename_sort_
;
1565 Sort_wildcard section_sort_
;
1568 // Return a relative priority of the section with the specified NAME
1569 // (a lower value meand a higher priority), or 0 if it should be compared
1570 // with others as strings.
1571 // The implementation of this function is copied from ld/ldlang.c.
1574 Input_section_sorter::get_init_priority(const char* name
)
1577 unsigned long init_priority
;
1579 // GCC uses the following section names for the init_priority
1580 // attribute with numerical values 101 and 65535 inclusive. A
1581 // lower value means a higher priority.
1583 // 1: .init_array.NNNN/.fini_array.NNNN: Where NNNN is the
1584 // decimal numerical value of the init_priority attribute.
1585 // The order of execution in .init_array is forward and
1586 // .fini_array is backward.
1587 // 2: .ctors.NNNN/.dtors.NNNN: Where NNNN is 65535 minus the
1588 // decimal numerical value of the init_priority attribute.
1589 // The order of execution in .ctors is backward and .dtors
1592 if (strncmp(name
, ".init_array.", 12) == 0
1593 || strncmp(name
, ".fini_array.", 12) == 0)
1595 init_priority
= strtoul(name
+ 12, &end
, 10);
1596 return *end
? 0 : init_priority
;
1598 else if (strncmp(name
, ".ctors.", 7) == 0
1599 || strncmp(name
, ".dtors.", 7) == 0)
1601 init_priority
= strtoul(name
+ 7, &end
, 10);
1602 return *end
? 0 : 65535 - init_priority
;
1609 Input_section_sorter::operator()(const Input_section_info
& isi1
,
1610 const Input_section_info
& isi2
) const
1612 if (this->section_sort_
== SORT_WILDCARD_BY_INIT_PRIORITY
)
1614 unsigned long ip1
= get_init_priority(isi1
.section_name().c_str());
1615 unsigned long ip2
= get_init_priority(isi2
.section_name().c_str());
1616 if (ip1
!= 0 && ip2
!= 0 && ip1
!= ip2
)
1619 if (this->section_sort_
== SORT_WILDCARD_BY_NAME
1620 || this->section_sort_
== SORT_WILDCARD_BY_NAME_BY_ALIGNMENT
1621 || (this->section_sort_
== SORT_WILDCARD_BY_ALIGNMENT_BY_NAME
1622 && isi1
.addralign() == isi2
.addralign())
1623 || this->section_sort_
== SORT_WILDCARD_BY_INIT_PRIORITY
)
1625 if (isi1
.section_name() != isi2
.section_name())
1626 return isi1
.section_name() < isi2
.section_name();
1628 if (this->section_sort_
== SORT_WILDCARD_BY_ALIGNMENT
1629 || this->section_sort_
== SORT_WILDCARD_BY_NAME_BY_ALIGNMENT
1630 || this->section_sort_
== SORT_WILDCARD_BY_ALIGNMENT_BY_NAME
)
1632 if (isi1
.addralign() != isi2
.addralign())
1633 return isi1
.addralign() < isi2
.addralign();
1635 if (this->filename_sort_
== SORT_WILDCARD_BY_NAME
)
1637 if (isi1
.relobj()->name() != isi2
.relobj()->name())
1638 return (isi1
.relobj()->name() < isi2
.relobj()->name());
1641 // Otherwise we leave them in the same order.
1645 // Set the section address. Look in INPUT_SECTIONS for sections which
1646 // match this spec, sort them as specified, and add them to the output
1650 Output_section_element_input::set_section_addresses(
1653 Output_section
* output_section
,
1655 uint64_t* dot_value
,
1657 Output_section
** dot_section
,
1659 Input_section_list
* input_sections
)
1661 // We build a list of sections which match each
1662 // Input_section_pattern.
1664 // If none of the patterns specify a sort option, we throw all
1665 // matching input sections into a single bin, in the order we
1666 // find them. Otherwise, we put matching input sections into
1667 // a separate bin for each pattern, and sort each one as
1668 // specified. Thus, an input section spec like this:
1670 // will group all .foo and .bar sections in the order seen,
1673 // will group all .foo sections followed by all .bar sections.
1674 // This matches Gnu ld behavior.
1676 // Things get really weird, though, when you add a sort spec
1677 // on some, but not all, of the patterns, like this:
1678 // *(SORT_BY_NAME(.foo) .bar)
1679 // We do not attempt to match Gnu ld behavior in this case.
1681 typedef std::vector
<std::vector
<Input_section_info
> > Matching_sections
;
1682 size_t input_pattern_count
= this->input_section_patterns_
.size();
1683 size_t bin_count
= 1;
1684 bool any_patterns_with_sort
= false;
1685 for (size_t i
= 0; i
< input_pattern_count
; ++i
)
1687 const Input_section_pattern
& isp(this->input_section_patterns_
[i
]);
1688 if (isp
.sort
!= SORT_WILDCARD_NONE
)
1689 any_patterns_with_sort
= true;
1691 if (any_patterns_with_sort
)
1692 bin_count
= input_pattern_count
;
1693 Matching_sections
matching_sections(bin_count
);
1695 // Look through the list of sections for this output section. Add
1696 // each one which matches to one of the elements of
1697 // MATCHING_SECTIONS.
1699 Input_section_list::iterator p
= input_sections
->begin();
1700 while (p
!= input_sections
->end())
1702 Relobj
* relobj
= p
->relobj();
1703 unsigned int shndx
= p
->shndx();
1704 Input_section_info
isi(*p
);
1706 // Calling section_name and section_addralign is not very
1709 // Lock the object so that we can get information about the
1710 // section. This is OK since we know we are single-threaded
1713 const Task
* task
= reinterpret_cast<const Task
*>(-1);
1714 Task_lock_obj
<Object
> tl(task
, relobj
);
1716 isi
.set_section_name(relobj
->section_name(shndx
));
1717 if (p
->is_relaxed_input_section())
1719 // We use current data size because relaxed section sizes may not
1720 // have finalized yet.
1721 isi
.set_size(p
->relaxed_input_section()->current_data_size());
1722 isi
.set_addralign(p
->relaxed_input_section()->addralign());
1726 isi
.set_size(relobj
->section_size(shndx
));
1727 isi
.set_addralign(relobj
->section_addralign(shndx
));
1731 if (!this->match_file_name(relobj
->name().c_str()))
1733 else if (this->input_section_patterns_
.empty())
1735 matching_sections
[0].push_back(isi
);
1736 p
= input_sections
->erase(p
);
1741 for (i
= 0; i
< input_pattern_count
; ++i
)
1743 const Input_section_pattern
&
1744 isp(this->input_section_patterns_
[i
]);
1745 if (match(isi
.section_name().c_str(), isp
.pattern
.c_str(),
1746 isp
.pattern_is_wildcard
))
1750 if (i
>= input_pattern_count
)
1756 matching_sections
[i
].push_back(isi
);
1757 p
= input_sections
->erase(p
);
1762 // Look through MATCHING_SECTIONS. Sort each one as specified,
1763 // using a stable sort so that we get the default order when
1764 // sections are otherwise equal. Add each input section to the
1767 uint64_t dot
= *dot_value
;
1768 for (size_t i
= 0; i
< bin_count
; ++i
)
1770 if (matching_sections
[i
].empty())
1773 gold_assert(output_section
!= NULL
);
1775 const Input_section_pattern
& isp(this->input_section_patterns_
[i
]);
1776 if (isp
.sort
!= SORT_WILDCARD_NONE
1777 || this->filename_sort_
!= SORT_WILDCARD_NONE
)
1778 std::stable_sort(matching_sections
[i
].begin(),
1779 matching_sections
[i
].end(),
1780 Input_section_sorter(this->filename_sort_
,
1783 for (std::vector
<Input_section_info
>::const_iterator p
=
1784 matching_sections
[i
].begin();
1785 p
!= matching_sections
[i
].end();
1788 // Override the original address alignment if SUBALIGN is specified.
1789 // We need to make a copy of the input section to modify the
1791 Output_section::Input_section
sis(p
->input_section());
1793 uint64_t this_subalign
= sis
.addralign();
1794 if (!sis
.is_input_section())
1795 sis
.output_section_data()->finalize_data_size();
1796 uint64_t data_size
= sis
.data_size();
1799 this_subalign
= subalign
;
1800 sis
.set_addralign(subalign
);
1803 uint64_t address
= align_address(dot
, this_subalign
);
1805 if (address
> dot
&& !fill
->empty())
1807 section_size_type length
=
1808 convert_to_section_size_type(address
- dot
);
1809 std::string this_fill
= this->get_fill_string(fill
, length
);
1810 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
1811 output_section
->add_output_section_data(posd
);
1812 layout
->new_output_section_data_from_script(posd
);
1815 output_section
->add_script_input_section(sis
);
1816 dot
= address
+ data_size
;
1820 // An SHF_TLS/SHT_NOBITS section does not take up any
1822 if (output_section
== NULL
1823 || (output_section
->flags() & elfcpp::SHF_TLS
) == 0
1824 || output_section
->type() != elfcpp::SHT_NOBITS
)
1827 this->final_dot_value_
= *dot_value
;
1828 this->final_dot_section_
= *dot_section
;
1831 // Print for debugging.
1834 Output_section_element_input::print(FILE* f
) const
1839 fprintf(f
, "KEEP(");
1841 if (!this->filename_pattern_
.empty())
1843 bool need_close_paren
= false;
1844 switch (this->filename_sort_
)
1846 case SORT_WILDCARD_NONE
:
1848 case SORT_WILDCARD_BY_NAME
:
1849 fprintf(f
, "SORT_BY_NAME(");
1850 need_close_paren
= true;
1856 fprintf(f
, "%s", this->filename_pattern_
.c_str());
1858 if (need_close_paren
)
1862 if (!this->input_section_patterns_
.empty()
1863 || !this->filename_exclusions_
.empty())
1867 bool need_space
= false;
1868 if (!this->filename_exclusions_
.empty())
1870 fprintf(f
, "EXCLUDE_FILE(");
1871 bool need_comma
= false;
1872 for (Filename_exclusions::const_iterator p
=
1873 this->filename_exclusions_
.begin();
1874 p
!= this->filename_exclusions_
.end();
1879 fprintf(f
, "%s", p
->first
.c_str());
1886 for (Input_section_patterns::const_iterator p
=
1887 this->input_section_patterns_
.begin();
1888 p
!= this->input_section_patterns_
.end();
1894 int close_parens
= 0;
1897 case SORT_WILDCARD_NONE
:
1899 case SORT_WILDCARD_BY_NAME
:
1900 fprintf(f
, "SORT_BY_NAME(");
1903 case SORT_WILDCARD_BY_ALIGNMENT
:
1904 fprintf(f
, "SORT_BY_ALIGNMENT(");
1907 case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT
:
1908 fprintf(f
, "SORT_BY_NAME(SORT_BY_ALIGNMENT(");
1911 case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME
:
1912 fprintf(f
, "SORT_BY_ALIGNMENT(SORT_BY_NAME(");
1915 case SORT_WILDCARD_BY_INIT_PRIORITY
:
1916 fprintf(f
, "SORT_BY_INIT_PRIORITY(");
1923 fprintf(f
, "%s", p
->pattern
.c_str());
1925 for (int i
= 0; i
< close_parens
; ++i
)
1940 // An output section.
1942 class Output_section_definition
: public Sections_element
1945 typedef Output_section_element::Input_section_list Input_section_list
;
1947 Output_section_definition(const char* name
, size_t namelen
,
1948 const Parser_output_section_header
* header
);
1950 // Finish the output section with the information in the trailer.
1952 finish(const Parser_output_section_trailer
* trailer
);
1954 // Add a symbol to be defined.
1956 add_symbol_assignment(const char* name
, size_t length
, Expression
* value
,
1957 bool provide
, bool hidden
);
1959 // Add an assignment to the special dot symbol.
1961 add_dot_assignment(Expression
* value
);
1963 // Add an assertion.
1965 add_assertion(Expression
* check
, const char* message
, size_t messagelen
);
1967 // Add a data item to the current output section.
1969 add_data(int size
, bool is_signed
, Expression
* val
);
1971 // Add a setting for the fill value.
1973 add_fill(Expression
* val
);
1975 // Add an input section specification.
1977 add_input_section(const Input_section_spec
* spec
, bool keep
);
1979 // Return whether the output section is relro.
1982 { return this->is_relro_
; }
1984 // Record that the output section is relro.
1987 { this->is_relro_
= true; }
1989 // Create any required output sections.
1991 create_sections(Layout
*);
1993 // Add any symbols being defined to the symbol table.
1995 add_symbols_to_table(Symbol_table
* symtab
);
1997 // Finalize symbols and check assertions.
1999 finalize_symbols(Symbol_table
*, const Layout
*, uint64_t*);
2001 // Return the output section name to use for an input file name and
2004 output_section_name(const char* file_name
, const char* section_name
,
2005 Output_section
***, Script_sections::Section_type
*,
2008 // Initialize OSP with an output section.
2010 orphan_section_init(Orphan_section_placement
* osp
,
2011 Script_sections::Elements_iterator p
)
2012 { osp
->output_section_init(this->name_
, this->output_section_
, p
); }
2014 // Set the section address.
2016 set_section_addresses(Symbol_table
* symtab
, Layout
* layout
,
2017 uint64_t* dot_value
, uint64_t*,
2018 uint64_t* load_address
);
2020 // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
2021 // this section is constrained, and the input sections do not match,
2022 // return the constraint, and set *POSD.
2024 check_constraint(Output_section_definition
** posd
);
2026 // See if this is the alternate output section for a constrained
2027 // output section. If it is, transfer the Output_section and return
2028 // true. Otherwise return false.
2030 alternate_constraint(Output_section_definition
*, Section_constraint
);
2032 // Get the list of segments to use for an allocated section when
2033 // using a PHDRS clause.
2035 allocate_to_segment(String_list
** phdrs_list
, bool* orphan
);
2037 // Look for an output section by name and return the address, the
2038 // load address, the alignment, and the size. This is used when an
2039 // expression refers to an output section which was not actually
2040 // created. This returns true if the section was found, false
2043 get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*,
2046 // Return the associated Output_section if there is one.
2048 get_output_section() const
2049 { return this->output_section_
; }
2051 // Print the contents to the FILE. This is for debugging.
2055 // Return the output section type if specified or Script_sections::ST_NONE.
2056 Script_sections::Section_type
2057 section_type() const;
2059 // Store the memory region to use.
2061 set_memory_region(Memory_region
*, bool set_vma
);
2064 set_section_vma(Expression
* address
)
2065 { this->address_
= address
; }
2068 set_section_lma(Expression
* address
)
2069 { this->load_address_
= address
; }
2072 get_section_name() const
2073 { return this->name_
; }
2077 script_section_type_name(Script_section_type
);
2079 typedef std::vector
<Output_section_element
*> Output_section_elements
;
2081 // The output section name.
2083 // The address. This may be NULL.
2084 Expression
* address_
;
2085 // The load address. This may be NULL.
2086 Expression
* load_address_
;
2087 // The alignment. This may be NULL.
2089 // The input section alignment. This may be NULL.
2090 Expression
* subalign_
;
2091 // The constraint, if any.
2092 Section_constraint constraint_
;
2093 // The fill value. This may be NULL.
2095 // The list of segments this section should go into. This may be
2097 String_list
* phdrs_
;
2098 // The list of elements defining the section.
2099 Output_section_elements elements_
;
2100 // The Output_section created for this definition. This will be
2101 // NULL if none was created.
2102 Output_section
* output_section_
;
2103 // The address after it has been evaluated.
2104 uint64_t evaluated_address_
;
2105 // The load address after it has been evaluated.
2106 uint64_t evaluated_load_address_
;
2107 // The alignment after it has been evaluated.
2108 uint64_t evaluated_addralign_
;
2109 // The output section is relro.
2111 // The output section type if specified.
2112 enum Script_section_type script_section_type_
;
2117 Output_section_definition::Output_section_definition(
2120 const Parser_output_section_header
* header
)
2121 : name_(name
, namelen
),
2122 address_(header
->address
),
2123 load_address_(header
->load_address
),
2124 align_(header
->align
),
2125 subalign_(header
->subalign
),
2126 constraint_(header
->constraint
),
2130 output_section_(NULL
),
2131 evaluated_address_(0),
2132 evaluated_load_address_(0),
2133 evaluated_addralign_(0),
2135 script_section_type_(header
->section_type
)
2139 // Finish an output section.
2142 Output_section_definition::finish(const Parser_output_section_trailer
* trailer
)
2144 this->fill_
= trailer
->fill
;
2145 this->phdrs_
= trailer
->phdrs
;
2148 // Add a symbol to be defined.
2151 Output_section_definition::add_symbol_assignment(const char* name
,
2157 Output_section_element
* p
= new Output_section_element_assignment(name
,
2162 this->elements_
.push_back(p
);
2165 // Add an assignment to the special dot symbol.
2168 Output_section_definition::add_dot_assignment(Expression
* value
)
2170 Output_section_element
* p
= new Output_section_element_dot_assignment(value
);
2171 this->elements_
.push_back(p
);
2174 // Add an assertion.
2177 Output_section_definition::add_assertion(Expression
* check
,
2178 const char* message
,
2181 Output_section_element
* p
= new Output_section_element_assertion(check
,
2184 this->elements_
.push_back(p
);
2187 // Add a data item to the current output section.
2190 Output_section_definition::add_data(int size
, bool is_signed
, Expression
* val
)
2192 Output_section_element
* p
= new Output_section_element_data(size
, is_signed
,
2194 this->elements_
.push_back(p
);
2197 // Add a setting for the fill value.
2200 Output_section_definition::add_fill(Expression
* val
)
2202 Output_section_element
* p
= new Output_section_element_fill(val
);
2203 this->elements_
.push_back(p
);
2206 // Add an input section specification.
2209 Output_section_definition::add_input_section(const Input_section_spec
* spec
,
2212 Output_section_element
* p
= new Output_section_element_input(spec
, keep
);
2213 this->elements_
.push_back(p
);
2216 // Create any required output sections. We need an output section if
2217 // there is a data statement here.
2220 Output_section_definition::create_sections(Layout
* layout
)
2222 if (this->output_section_
!= NULL
)
2224 for (Output_section_elements::const_iterator p
= this->elements_
.begin();
2225 p
!= this->elements_
.end();
2228 if ((*p
)->needs_output_section())
2230 const char* name
= this->name_
.c_str();
2231 this->output_section_
=
2232 layout
->make_output_section_for_script(name
, this->section_type());
2238 // Add any symbols being defined to the symbol table.
2241 Output_section_definition::add_symbols_to_table(Symbol_table
* symtab
)
2243 for (Output_section_elements::iterator p
= this->elements_
.begin();
2244 p
!= this->elements_
.end();
2246 (*p
)->add_symbols_to_table(symtab
);
2249 // Finalize symbols and check assertions.
2252 Output_section_definition::finalize_symbols(Symbol_table
* symtab
,
2253 const Layout
* layout
,
2254 uint64_t* dot_value
)
2256 if (this->output_section_
!= NULL
)
2257 *dot_value
= this->output_section_
->address();
2260 uint64_t address
= *dot_value
;
2261 if (this->address_
!= NULL
)
2263 address
= this->address_
->eval_with_dot(symtab
, layout
, true,
2267 if (this->align_
!= NULL
)
2269 uint64_t align
= this->align_
->eval_with_dot(symtab
, layout
, true,
2272 address
= align_address(address
, align
);
2274 *dot_value
= address
;
2277 Output_section
* dot_section
= this->output_section_
;
2278 for (Output_section_elements::iterator p
= this->elements_
.begin();
2279 p
!= this->elements_
.end();
2281 (*p
)->finalize_symbols(symtab
, layout
, dot_value
, &dot_section
);
2284 // Return the output section name to use for an input section name.
2287 Output_section_definition::output_section_name(
2288 const char* file_name
,
2289 const char* section_name
,
2290 Output_section
*** slot
,
2291 Script_sections::Section_type
* psection_type
,
2294 // Ask each element whether it matches NAME.
2295 for (Output_section_elements::const_iterator p
= this->elements_
.begin();
2296 p
!= this->elements_
.end();
2299 if ((*p
)->match_name(file_name
, section_name
, keep
))
2301 // We found a match for NAME, which means that it should go
2302 // into this output section.
2303 *slot
= &this->output_section_
;
2304 *psection_type
= this->section_type();
2305 return this->name_
.c_str();
2309 // We don't know about this section name.
2313 // Return true if memory from START to START + LENGTH is contained
2314 // within a memory region.
2317 Script_sections::block_in_region(Symbol_table
* symtab
, Layout
* layout
,
2318 uint64_t start
, uint64_t length
) const
2320 if (this->memory_regions_
== NULL
)
2323 for (Memory_regions::const_iterator mr
= this->memory_regions_
->begin();
2324 mr
!= this->memory_regions_
->end();
2327 uint64_t s
= (*mr
)->start_address()->eval(symtab
, layout
, false);
2328 uint64_t l
= (*mr
)->length()->eval(symtab
, layout
, false);
2331 && (s
+ l
) >= (start
+ length
))
2338 // Find a memory region that should be used by a given output SECTION.
2339 // If provided set PREVIOUS_SECTION_RETURN to point to the last section
2340 // that used the return memory region.
2343 Script_sections::find_memory_region(
2344 Output_section_definition
* section
,
2345 bool find_vma_region
,
2347 Output_section_definition
** previous_section_return
)
2349 if (previous_section_return
!= NULL
)
2350 * previous_section_return
= NULL
;
2352 // Walk the memory regions specified in this script, if any.
2353 if (this->memory_regions_
== NULL
)
2356 // The /DISCARD/ section never gets assigned to any region.
2357 if (section
->get_section_name() == "/DISCARD/")
2360 Memory_region
* first_match
= NULL
;
2362 // First check to see if a region has been assigned to this section.
2363 for (Memory_regions::const_iterator mr
= this->memory_regions_
->begin();
2364 mr
!= this->memory_regions_
->end();
2367 if (find_vma_region
)
2369 for (Memory_region::Section_list::const_iterator s
=
2370 (*mr
)->get_vma_section_list_start();
2371 s
!= (*mr
)->get_vma_section_list_end();
2373 if ((*s
) == section
)
2375 (*mr
)->set_last_section(section
);
2381 for (Memory_region::Section_list::const_iterator s
=
2382 (*mr
)->get_lma_section_list_start();
2383 s
!= (*mr
)->get_lma_section_list_end();
2385 if ((*s
) == section
)
2387 (*mr
)->set_last_section(section
);
2394 // Make a note of the first memory region whose attributes
2395 // are compatible with the section. If we do not find an
2396 // explicit region assignment, then we will return this region.
2397 Output_section
* out_sec
= section
->get_output_section();
2398 if (first_match
== NULL
2400 && (*mr
)->attributes_compatible(out_sec
->flags(),
2406 // With LMA computations, if an explicit region has not been specified then
2407 // we will want to set the difference between the VMA and the LMA of the
2408 // section were searching for to be the same as the difference between the
2409 // VMA and LMA of the last section to be added to first matched region.
2410 // Hence, if it was asked for, we return a pointer to the last section
2411 // known to be used by the first matched region.
2412 if (first_match
!= NULL
2413 && previous_section_return
!= NULL
)
2414 *previous_section_return
= first_match
->get_last_section();
2419 // Set the section address. Note that the OUTPUT_SECTION_ field will
2420 // be NULL if no input sections were mapped to this output section.
2421 // We still have to adjust dot and process symbol assignments.
2424 Output_section_definition::set_section_addresses(Symbol_table
* symtab
,
2426 uint64_t* dot_value
,
2427 uint64_t* dot_alignment
,
2428 uint64_t* load_address
)
2430 Memory_region
* vma_region
= NULL
;
2431 Memory_region
* lma_region
= NULL
;
2432 Script_sections
* script_sections
=
2433 layout
->script_options()->script_sections();
2435 uint64_t old_dot_value
= *dot_value
;
2436 uint64_t old_load_address
= *load_address
;
2438 // If input section sorting is requested via --section-ordering-file or
2439 // linker plugins, then do it here. This is important because we want
2440 // any sorting specified in the linker scripts, which will be done after
2441 // this, to take precedence. The final order of input sections is then
2442 // guaranteed to be according to the linker script specification.
2443 if (this->output_section_
!= NULL
2444 && this->output_section_
->input_section_order_specified())
2445 this->output_section_
->sort_attached_input_sections();
2447 // Decide the start address for the section. The algorithm is:
2448 // 1) If an address has been specified in a linker script, use that.
2449 // 2) Otherwise if a memory region has been specified for the section,
2450 // use the next free address in the region.
2451 // 3) Otherwise if memory regions have been specified find the first
2452 // region whose attributes are compatible with this section and
2453 // install it into that region.
2454 // 4) Otherwise use the current location counter.
2456 if (this->output_section_
!= NULL
2457 // Check for --section-start.
2458 && parameters
->options().section_start(this->output_section_
->name(),
2461 else if (this->address_
== NULL
)
2463 vma_region
= script_sections
->find_memory_region(this, true, false, NULL
);
2464 if (vma_region
!= NULL
)
2465 address
= vma_region
->get_current_address()->eval(symtab
, layout
,
2468 address
= *dot_value
;
2472 vma_region
= script_sections
->find_memory_region(this, true, true, NULL
);
2473 address
= this->address_
->eval_with_dot(symtab
, layout
, true,
2474 *dot_value
, NULL
, NULL
,
2475 dot_alignment
, false);
2476 if (vma_region
!= NULL
)
2477 vma_region
->set_address(address
, symtab
, layout
);
2481 if (this->align_
== NULL
)
2483 if (this->output_section_
== NULL
)
2486 align
= this->output_section_
->addralign();
2490 Output_section
* align_section
;
2491 align
= this->align_
->eval_with_dot(symtab
, layout
, true, *dot_value
,
2492 NULL
, &align_section
, NULL
, false);
2493 if (align_section
!= NULL
)
2494 gold_warning(_("alignment of section %s is not absolute"),
2495 this->name_
.c_str());
2496 if (this->output_section_
!= NULL
)
2497 this->output_section_
->set_addralign(align
);
2501 if (this->subalign_
== NULL
)
2505 Output_section
* subalign_section
;
2506 subalign
= this->subalign_
->eval_with_dot(symtab
, layout
, true,
2508 &subalign_section
, NULL
,
2510 if (subalign_section
!= NULL
)
2511 gold_warning(_("subalign of section %s is not absolute"),
2512 this->name_
.c_str());
2514 // Reserve a value of 0 to mean there is no SUBALIGN property.
2518 // The external alignment of the output section must be at least
2519 // as large as that of the input sections. If there is no
2520 // explicit ALIGN property, we set the output section alignment
2521 // to match the input section alignment.
2522 if (align
< subalign
|| this->align_
== NULL
)
2525 this->output_section_
->set_addralign(align
);
2529 address
= align_address(address
, align
);
2531 uint64_t start_address
= address
;
2533 *dot_value
= address
;
2535 // Except for NOLOAD sections, the address of non-SHF_ALLOC sections is
2536 // forced to zero, regardless of what the linker script wants.
2537 if (this->output_section_
!= NULL
2538 && ((this->output_section_
->flags() & elfcpp::SHF_ALLOC
) != 0
2539 || this->output_section_
->is_noload()))
2540 this->output_section_
->set_address(address
);
2542 this->evaluated_address_
= address
;
2543 this->evaluated_addralign_
= align
;
2547 if (this->load_address_
== NULL
)
2549 Output_section_definition
* previous_section
;
2551 // Determine if an LMA region has been set for this section.
2552 lma_region
= script_sections
->find_memory_region(this, false, false,
2555 if (lma_region
!= NULL
)
2557 if (previous_section
== NULL
)
2558 // The LMA address was explicitly set to the given region.
2559 laddr
= lma_region
->get_current_address()->eval(symtab
, layout
,
2563 // We are not going to use the discovered lma_region, so
2564 // make sure that we do not update it in the code below.
2567 if (this->address_
!= NULL
|| previous_section
== this)
2569 // Either an explicit VMA address has been set, or an
2570 // explicit VMA region has been set, so set the LMA equal to
2576 // The LMA address was not explicitly or implicitly set.
2578 // We have been given the first memory region that is
2579 // compatible with the current section and a pointer to the
2580 // last section to use this region. Set the LMA of this
2581 // section so that the difference between its' VMA and LMA
2582 // is the same as the difference between the VMA and LMA of
2583 // the last section in the given region.
2584 laddr
= address
+ (previous_section
->evaluated_load_address_
2585 - previous_section
->evaluated_address_
);
2589 if (this->output_section_
!= NULL
)
2590 this->output_section_
->set_load_address(laddr
);
2594 // Do not set the load address of the output section, if one exists.
2595 // This allows future sections to determine what the load address
2596 // should be. If none is ever set, it will default to being the
2597 // same as the vma address.
2603 laddr
= this->load_address_
->eval_with_dot(symtab
, layout
, true,
2605 this->output_section_
,
2607 if (this->output_section_
!= NULL
)
2608 this->output_section_
->set_load_address(laddr
);
2611 this->evaluated_load_address_
= laddr
;
2614 if (this->fill_
!= NULL
)
2616 // FIXME: The GNU linker supports fill values of arbitrary
2618 Output_section
* fill_section
;
2619 uint64_t fill_val
= this->fill_
->eval_with_dot(symtab
, layout
, true,
2621 NULL
, &fill_section
,
2623 if (fill_section
!= NULL
)
2624 gold_warning(_("fill of section %s is not absolute"),
2625 this->name_
.c_str());
2626 unsigned char fill_buff
[4];
2627 elfcpp::Swap_unaligned
<32, true>::writeval(fill_buff
, fill_val
);
2628 fill
.assign(reinterpret_cast<char*>(fill_buff
), 4);
2631 Input_section_list input_sections
;
2632 if (this->output_section_
!= NULL
)
2634 // Get the list of input sections attached to this output
2635 // section. This will leave the output section with only
2636 // Output_section_data entries.
2637 address
+= this->output_section_
->get_input_sections(address
,
2640 *dot_value
= address
;
2643 Output_section
* dot_section
= this->output_section_
;
2644 for (Output_section_elements::iterator p
= this->elements_
.begin();
2645 p
!= this->elements_
.end();
2647 (*p
)->set_section_addresses(symtab
, layout
, this->output_section_
,
2648 subalign
, dot_value
, dot_alignment
,
2649 &dot_section
, &fill
, &input_sections
);
2651 gold_assert(input_sections
.empty());
2653 if (vma_region
!= NULL
)
2655 // Update the VMA region being used by the section now that we know how
2656 // big it is. Use the current address in the region, rather than
2657 // start_address because that might have been aligned upwards and we
2658 // need to allow for the padding.
2659 Expression
* addr
= vma_region
->get_current_address();
2660 uint64_t size
= *dot_value
- addr
->eval(symtab
, layout
, false);
2662 vma_region
->increment_offset(this->get_section_name(), size
,
2666 // If the LMA region is different from the VMA region, then increment the
2667 // offset there as well. Note that we use the same "dot_value -
2668 // start_address" formula that is used in the load_address assignment below.
2669 if (lma_region
!= NULL
&& lma_region
!= vma_region
)
2670 lma_region
->increment_offset(this->get_section_name(),
2671 *dot_value
- start_address
,
2674 // Compute the load address for the following section.
2675 if (this->output_section_
== NULL
)
2676 *load_address
= *dot_value
;
2677 else if (this->load_address_
== NULL
)
2679 if (lma_region
== NULL
)
2680 *load_address
= *dot_value
;
2683 lma_region
->get_current_address()->eval(symtab
, layout
, false);
2686 *load_address
= (this->output_section_
->load_address()
2687 + (*dot_value
- start_address
));
2689 if (this->output_section_
!= NULL
)
2691 if (this->is_relro_
)
2692 this->output_section_
->set_is_relro();
2694 this->output_section_
->clear_is_relro();
2696 // If this is a NOLOAD section, keep dot and load address unchanged.
2697 if (this->output_section_
->is_noload())
2699 *dot_value
= old_dot_value
;
2700 *load_address
= old_load_address
;
2705 // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
2706 // this section is constrained, and the input sections do not match,
2707 // return the constraint, and set *POSD.
2710 Output_section_definition::check_constraint(Output_section_definition
** posd
)
2712 switch (this->constraint_
)
2714 case CONSTRAINT_NONE
:
2715 return CONSTRAINT_NONE
;
2717 case CONSTRAINT_ONLY_IF_RO
:
2718 if (this->output_section_
!= NULL
2719 && (this->output_section_
->flags() & elfcpp::SHF_WRITE
) != 0)
2722 return CONSTRAINT_ONLY_IF_RO
;
2724 return CONSTRAINT_NONE
;
2726 case CONSTRAINT_ONLY_IF_RW
:
2727 if (this->output_section_
!= NULL
2728 && (this->output_section_
->flags() & elfcpp::SHF_WRITE
) == 0)
2731 return CONSTRAINT_ONLY_IF_RW
;
2733 return CONSTRAINT_NONE
;
2735 case CONSTRAINT_SPECIAL
:
2736 if (this->output_section_
!= NULL
)
2737 gold_error(_("SPECIAL constraints are not implemented"));
2738 return CONSTRAINT_NONE
;
2745 // See if this is the alternate output section for a constrained
2746 // output section. If it is, transfer the Output_section and return
2747 // true. Otherwise return false.
2750 Output_section_definition::alternate_constraint(
2751 Output_section_definition
* posd
,
2752 Section_constraint constraint
)
2754 if (this->name_
!= posd
->name_
)
2759 case CONSTRAINT_ONLY_IF_RO
:
2760 if (this->constraint_
!= CONSTRAINT_ONLY_IF_RW
)
2764 case CONSTRAINT_ONLY_IF_RW
:
2765 if (this->constraint_
!= CONSTRAINT_ONLY_IF_RO
)
2773 // We have found the alternate constraint. We just need to move
2774 // over the Output_section. When constraints are used properly,
2775 // THIS should not have an output_section pointer, as all the input
2776 // sections should have matched the other definition.
2778 if (this->output_section_
!= NULL
)
2779 gold_error(_("mismatched definition for constrained sections"));
2781 this->output_section_
= posd
->output_section_
;
2782 posd
->output_section_
= NULL
;
2784 if (this->is_relro_
)
2785 this->output_section_
->set_is_relro();
2787 this->output_section_
->clear_is_relro();
2792 // Get the list of segments to use for an allocated section when using
2796 Output_section_definition::allocate_to_segment(String_list
** phdrs_list
,
2799 // Update phdrs_list even if we don't have an output section. It
2800 // might be used by the following sections.
2801 if (this->phdrs_
!= NULL
)
2802 *phdrs_list
= this->phdrs_
;
2804 if (this->output_section_
== NULL
)
2806 if ((this->output_section_
->flags() & elfcpp::SHF_ALLOC
) == 0)
2809 return this->output_section_
;
2812 // Look for an output section by name and return the address, the load
2813 // address, the alignment, and the size. This is used when an
2814 // expression refers to an output section which was not actually
2815 // created. This returns true if the section was found, false
2819 Output_section_definition::get_output_section_info(const char* name
,
2821 uint64_t* load_address
,
2822 uint64_t* addralign
,
2823 uint64_t* size
) const
2825 if (this->name_
!= name
)
2828 if (this->output_section_
!= NULL
)
2830 *address
= this->output_section_
->address();
2831 if (this->output_section_
->has_load_address())
2832 *load_address
= this->output_section_
->load_address();
2834 *load_address
= *address
;
2835 *addralign
= this->output_section_
->addralign();
2836 *size
= this->output_section_
->current_data_size();
2840 *address
= this->evaluated_address_
;
2841 *load_address
= this->evaluated_load_address_
;
2842 *addralign
= this->evaluated_addralign_
;
2849 // Print for debugging.
2852 Output_section_definition::print(FILE* f
) const
2854 fprintf(f
, " %s ", this->name_
.c_str());
2856 if (this->address_
!= NULL
)
2858 this->address_
->print(f
);
2862 if (this->script_section_type_
!= SCRIPT_SECTION_TYPE_NONE
)
2864 this->script_section_type_name(this->script_section_type_
));
2868 if (this->load_address_
!= NULL
)
2871 this->load_address_
->print(f
);
2875 if (this->align_
!= NULL
)
2877 fprintf(f
, "ALIGN(");
2878 this->align_
->print(f
);
2882 if (this->subalign_
!= NULL
)
2884 fprintf(f
, "SUBALIGN(");
2885 this->subalign_
->print(f
);
2891 for (Output_section_elements::const_iterator p
= this->elements_
.begin();
2892 p
!= this->elements_
.end();
2898 if (this->fill_
!= NULL
)
2901 this->fill_
->print(f
);
2904 if (this->phdrs_
!= NULL
)
2906 for (String_list::const_iterator p
= this->phdrs_
->begin();
2907 p
!= this->phdrs_
->end();
2909 fprintf(f
, " :%s", p
->c_str());
2915 Script_sections::Section_type
2916 Output_section_definition::section_type() const
2918 switch (this->script_section_type_
)
2920 case SCRIPT_SECTION_TYPE_NONE
:
2921 return Script_sections::ST_NONE
;
2922 case SCRIPT_SECTION_TYPE_NOLOAD
:
2923 return Script_sections::ST_NOLOAD
;
2924 case SCRIPT_SECTION_TYPE_COPY
:
2925 case SCRIPT_SECTION_TYPE_DSECT
:
2926 case SCRIPT_SECTION_TYPE_INFO
:
2927 case SCRIPT_SECTION_TYPE_OVERLAY
:
2928 // There are not really support so we treat them as ST_NONE. The
2929 // parse should have issued errors for them already.
2930 return Script_sections::ST_NONE
;
2936 // Return the name of a script section type.
2939 Output_section_definition::script_section_type_name(
2940 Script_section_type script_section_type
)
2942 switch (script_section_type
)
2944 case SCRIPT_SECTION_TYPE_NONE
:
2946 case SCRIPT_SECTION_TYPE_NOLOAD
:
2948 case SCRIPT_SECTION_TYPE_DSECT
:
2950 case SCRIPT_SECTION_TYPE_COPY
:
2952 case SCRIPT_SECTION_TYPE_INFO
:
2954 case SCRIPT_SECTION_TYPE_OVERLAY
:
2962 Output_section_definition::set_memory_region(Memory_region
* mr
, bool set_vma
)
2964 gold_assert(mr
!= NULL
);
2965 // Add the current section to the specified region's list.
2966 mr
->add_section(this, set_vma
);
2969 // An output section created to hold orphaned input sections. These
2970 // do not actually appear in linker scripts. However, for convenience
2971 // when setting the output section addresses, we put a marker to these
2972 // sections in the appropriate place in the list of SECTIONS elements.
2974 class Orphan_output_section
: public Sections_element
2977 Orphan_output_section(Output_section
* os
)
2981 // Return whether the orphan output section is relro. We can just
2982 // check the output section because we always set the flag, if
2983 // needed, just after we create the Orphan_output_section.
2986 { return this->os_
->is_relro(); }
2988 // Initialize OSP with an output section. This should have been
2991 orphan_section_init(Orphan_section_placement
*,
2992 Script_sections::Elements_iterator
)
2993 { gold_unreachable(); }
2995 // Set section addresses.
2997 set_section_addresses(Symbol_table
*, Layout
*, uint64_t*, uint64_t*,
3000 // Get the list of segments to use for an allocated section when
3001 // using a PHDRS clause.
3003 allocate_to_segment(String_list
**, bool*);
3005 // Return the associated Output_section.
3007 get_output_section() const
3008 { return this->os_
; }
3010 // Print for debugging.
3012 print(FILE* f
) const
3014 fprintf(f
, " marker for orphaned output section %s\n",
3019 Output_section
* os_
;
3022 // Set section addresses.
3025 Orphan_output_section::set_section_addresses(Symbol_table
*, Layout
*,
3026 uint64_t* dot_value
,
3028 uint64_t* load_address
)
3030 typedef std::list
<Output_section::Input_section
> Input_section_list
;
3032 bool have_load_address
= *load_address
!= *dot_value
;
3034 uint64_t address
= *dot_value
;
3035 address
= align_address(address
, this->os_
->addralign());
3037 // If input section sorting is requested via --section-ordering-file or
3038 // linker plugins, then do it here. This is important because we want
3039 // any sorting specified in the linker scripts, which will be done after
3040 // this, to take precedence. The final order of input sections is then
3041 // guaranteed to be according to the linker script specification.
3042 if (this->os_
!= NULL
3043 && this->os_
->input_section_order_specified())
3044 this->os_
->sort_attached_input_sections();
3046 // For a relocatable link, all orphan sections are put at
3047 // address 0. In general we expect all sections to be at
3048 // address 0 for a relocatable link, but we permit the linker
3049 // script to override that for specific output sections.
3050 if (parameters
->options().relocatable())
3054 have_load_address
= false;
3057 if ((this->os_
->flags() & elfcpp::SHF_ALLOC
) != 0)
3059 this->os_
->set_address(address
);
3060 if (have_load_address
)
3061 this->os_
->set_load_address(align_address(*load_address
,
3062 this->os_
->addralign()));
3065 Input_section_list input_sections
;
3066 address
+= this->os_
->get_input_sections(address
, "", &input_sections
);
3068 for (Input_section_list::iterator p
= input_sections
.begin();
3069 p
!= input_sections
.end();
3072 uint64_t addralign
= p
->addralign();
3073 if (!p
->is_input_section())
3074 p
->output_section_data()->finalize_data_size();
3075 uint64_t size
= p
->data_size();
3076 address
= align_address(address
, addralign
);
3077 this->os_
->add_script_input_section(*p
);
3081 if (parameters
->options().relocatable())
3083 // For a relocatable link, reset DOT_VALUE to 0.
3087 else if (this->os_
== NULL
3088 || (this->os_
->flags() & elfcpp::SHF_TLS
) == 0
3089 || this->os_
->type() != elfcpp::SHT_NOBITS
)
3091 // An SHF_TLS/SHT_NOBITS section does not take up any address space.
3092 if (!have_load_address
)
3093 *load_address
= address
;
3095 *load_address
+= address
- *dot_value
;
3097 *dot_value
= address
;
3101 // Get the list of segments to use for an allocated section when using
3102 // a PHDRS clause. If this is an allocated section, return the
3103 // Output_section. We don't change the list of segments.
3106 Orphan_output_section::allocate_to_segment(String_list
**, bool* orphan
)
3108 if ((this->os_
->flags() & elfcpp::SHF_ALLOC
) == 0)
3114 // Class Phdrs_element. A program header from a PHDRS clause.
3119 Phdrs_element(const char* name
, size_t namelen
, unsigned int type
,
3120 bool includes_filehdr
, bool includes_phdrs
,
3121 bool is_flags_valid
, unsigned int flags
,
3122 Expression
* load_address
)
3123 : name_(name
, namelen
), type_(type
), includes_filehdr_(includes_filehdr
),
3124 includes_phdrs_(includes_phdrs
), is_flags_valid_(is_flags_valid
),
3125 flags_(flags
), load_address_(load_address
), load_address_value_(0),
3129 // Return the name of this segment.
3132 { return this->name_
; }
3134 // Return the type of the segment.
3137 { return this->type_
; }
3139 // Whether to include the file header.
3141 includes_filehdr() const
3142 { return this->includes_filehdr_
; }
3144 // Whether to include the program headers.
3146 includes_phdrs() const
3147 { return this->includes_phdrs_
; }
3149 // Return whether there is a load address.
3151 has_load_address() const
3152 { return this->load_address_
!= NULL
; }
3154 // Evaluate the load address expression if there is one.
3156 eval_load_address(Symbol_table
* symtab
, Layout
* layout
)
3158 if (this->load_address_
!= NULL
)
3159 this->load_address_value_
= this->load_address_
->eval(symtab
, layout
,
3163 // Return the load address.
3165 load_address() const
3167 gold_assert(this->load_address_
!= NULL
);
3168 return this->load_address_value_
;
3171 // Create the segment.
3173 create_segment(Layout
* layout
)
3175 this->segment_
= layout
->make_output_segment(this->type_
, this->flags_
);
3176 return this->segment_
;
3179 // Return the segment.
3182 { return this->segment_
; }
3184 // Release the segment.
3187 { this->segment_
= NULL
; }
3189 // Set the segment flags if appropriate.
3191 set_flags_if_valid()
3193 if (this->is_flags_valid_
)
3194 this->segment_
->set_flags(this->flags_
);
3197 // Print for debugging.
3202 // The name used in the script.
3204 // The type of the segment (PT_LOAD, etc.).
3206 // Whether this segment includes the file header.
3207 bool includes_filehdr_
;
3208 // Whether this segment includes the section headers.
3209 bool includes_phdrs_
;
3210 // Whether the flags were explicitly specified.
3211 bool is_flags_valid_
;
3212 // The flags for this segment (PF_R, etc.) if specified.
3213 unsigned int flags_
;
3214 // The expression for the load address for this segment. This may
3216 Expression
* load_address_
;
3217 // The actual load address from evaluating the expression.
3218 uint64_t load_address_value_
;
3219 // The segment itself.
3220 Output_segment
* segment_
;
3223 // Print for debugging.
3226 Phdrs_element::print(FILE* f
) const
3228 fprintf(f
, " %s 0x%x", this->name_
.c_str(), this->type_
);
3229 if (this->includes_filehdr_
)
3230 fprintf(f
, " FILEHDR");
3231 if (this->includes_phdrs_
)
3232 fprintf(f
, " PHDRS");
3233 if (this->is_flags_valid_
)
3234 fprintf(f
, " FLAGS(%u)", this->flags_
);
3235 if (this->load_address_
!= NULL
)
3238 this->load_address_
->print(f
);
3244 // Add a memory region.
3247 Script_sections::add_memory_region(const char* name
, size_t namelen
,
3248 unsigned int attributes
,
3249 Expression
* start
, Expression
* length
)
3251 if (this->memory_regions_
== NULL
)
3252 this->memory_regions_
= new Memory_regions();
3253 else if (this->find_memory_region(name
, namelen
))
3255 gold_error(_("region '%.*s' already defined"), static_cast<int>(namelen
),
3257 // FIXME: Add a GOLD extension to allow multiple regions with the same
3258 // name. This would amount to a single region covering disjoint blocks
3259 // of memory, which is useful for embedded devices.
3262 // FIXME: Check the length and start values. Currently we allow
3263 // non-constant expressions for these values, whereas LD does not.
3265 // FIXME: Add a GOLD extension to allow NEGATIVE LENGTHS. This would
3266 // describe a region that packs from the end address going down, rather
3267 // than the start address going up. This would be useful for embedded
3270 this->memory_regions_
->push_back(new Memory_region(name
, namelen
, attributes
,
3274 // Find a memory region.
3277 Script_sections::find_memory_region(const char* name
, size_t namelen
)
3279 if (this->memory_regions_
== NULL
)
3282 for (Memory_regions::const_iterator m
= this->memory_regions_
->begin();
3283 m
!= this->memory_regions_
->end();
3285 if ((*m
)->name_match(name
, namelen
))
3291 // Find a memory region's origin.
3294 Script_sections::find_memory_region_origin(const char* name
, size_t namelen
)
3296 Memory_region
* mr
= find_memory_region(name
, namelen
);
3300 return mr
->start_address();
3303 // Find a memory region's length.
3306 Script_sections::find_memory_region_length(const char* name
, size_t namelen
)
3308 Memory_region
* mr
= find_memory_region(name
, namelen
);
3312 return mr
->length();
3315 // Set the memory region to use for the current section.
3318 Script_sections::set_memory_region(Memory_region
* mr
, bool set_vma
)
3320 gold_assert(!this->sections_elements_
->empty());
3321 this->sections_elements_
->back()->set_memory_region(mr
, set_vma
);
3324 // Class Script_sections.
3326 Script_sections::Script_sections()
3327 : saw_sections_clause_(false),
3328 in_sections_clause_(false),
3329 sections_elements_(NULL
),
3330 output_section_(NULL
),
3331 memory_regions_(NULL
),
3332 phdrs_elements_(NULL
),
3333 orphan_section_placement_(NULL
),
3334 data_segment_align_start_(),
3335 saw_data_segment_align_(false),
3336 saw_relro_end_(false),
3337 saw_segment_start_expression_(false),
3338 segments_created_(false)
3342 // Start a SECTIONS clause.
3345 Script_sections::start_sections()
3347 gold_assert(!this->in_sections_clause_
&& this->output_section_
== NULL
);
3348 this->saw_sections_clause_
= true;
3349 this->in_sections_clause_
= true;
3350 if (this->sections_elements_
== NULL
)
3351 this->sections_elements_
= new Sections_elements
;
3354 // Finish a SECTIONS clause.
3357 Script_sections::finish_sections()
3359 gold_assert(this->in_sections_clause_
&& this->output_section_
== NULL
);
3360 this->in_sections_clause_
= false;
3363 // Add a symbol to be defined.
3366 Script_sections::add_symbol_assignment(const char* name
, size_t length
,
3367 Expression
* val
, bool provide
,
3370 if (this->output_section_
!= NULL
)
3371 this->output_section_
->add_symbol_assignment(name
, length
, val
,
3375 Sections_element
* p
= new Sections_element_assignment(name
, length
,
3378 this->sections_elements_
->push_back(p
);
3382 // Add an assignment to the special dot symbol.
3385 Script_sections::add_dot_assignment(Expression
* val
)
3387 if (this->output_section_
!= NULL
)
3388 this->output_section_
->add_dot_assignment(val
);
3391 // The GNU linker permits assignments to . to appears outside of
3392 // a SECTIONS clause, and treats it as appearing inside, so
3393 // sections_elements_ may be NULL here.
3394 if (this->sections_elements_
== NULL
)
3396 this->sections_elements_
= new Sections_elements
;
3397 this->saw_sections_clause_
= true;
3400 Sections_element
* p
= new Sections_element_dot_assignment(val
);
3401 this->sections_elements_
->push_back(p
);
3405 // Add an assertion.
3408 Script_sections::add_assertion(Expression
* check
, const char* message
,
3411 if (this->output_section_
!= NULL
)
3412 this->output_section_
->add_assertion(check
, message
, messagelen
);
3415 Sections_element
* p
= new Sections_element_assertion(check
, message
,
3417 this->sections_elements_
->push_back(p
);
3421 // Start processing entries for an output section.
3424 Script_sections::start_output_section(
3427 const Parser_output_section_header
* header
)
3429 Output_section_definition
* posd
= new Output_section_definition(name
,
3432 this->sections_elements_
->push_back(posd
);
3433 gold_assert(this->output_section_
== NULL
);
3434 this->output_section_
= posd
;
3437 // Stop processing entries for an output section.
3440 Script_sections::finish_output_section(
3441 const Parser_output_section_trailer
* trailer
)
3443 gold_assert(this->output_section_
!= NULL
);
3444 this->output_section_
->finish(trailer
);
3445 this->output_section_
= NULL
;
3448 // Add a data item to the current output section.
3451 Script_sections::add_data(int size
, bool is_signed
, Expression
* val
)
3453 gold_assert(this->output_section_
!= NULL
);
3454 this->output_section_
->add_data(size
, is_signed
, val
);
3457 // Add a fill value setting to the current output section.
3460 Script_sections::add_fill(Expression
* val
)
3462 gold_assert(this->output_section_
!= NULL
);
3463 this->output_section_
->add_fill(val
);
3466 // Add an input section specification to the current output section.
3469 Script_sections::add_input_section(const Input_section_spec
* spec
, bool keep
)
3471 gold_assert(this->output_section_
!= NULL
);
3472 this->output_section_
->add_input_section(spec
, keep
);
3475 // This is called when we see DATA_SEGMENT_ALIGN. It means that any
3476 // subsequent output sections may be relro.
3479 Script_sections::data_segment_align()
3481 if (this->saw_data_segment_align_
)
3482 gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script"));
3483 gold_assert(!this->sections_elements_
->empty());
3484 Sections_elements::iterator p
= this->sections_elements_
->end();
3486 this->data_segment_align_start_
= p
;
3487 this->saw_data_segment_align_
= true;
3490 // This is called when we see DATA_SEGMENT_RELRO_END. It means that
3491 // any output sections seen since DATA_SEGMENT_ALIGN are relro.
3494 Script_sections::data_segment_relro_end()
3496 if (this->saw_relro_end_
)
3497 gold_error(_("DATA_SEGMENT_RELRO_END may only appear once "
3498 "in a linker script"));
3499 this->saw_relro_end_
= true;
3501 if (!this->saw_data_segment_align_
)
3502 gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN"));
3505 Sections_elements::iterator p
= this->data_segment_align_start_
;
3506 for (++p
; p
!= this->sections_elements_
->end(); ++p
)
3507 (*p
)->set_is_relro();
3511 // Create any required sections.
3514 Script_sections::create_sections(Layout
* layout
)
3516 if (!this->saw_sections_clause_
)
3518 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3519 p
!= this->sections_elements_
->end();
3521 (*p
)->create_sections(layout
);
3524 // Add any symbols we are defining to the symbol table.
3527 Script_sections::add_symbols_to_table(Symbol_table
* symtab
)
3529 if (!this->saw_sections_clause_
)
3531 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3532 p
!= this->sections_elements_
->end();
3534 (*p
)->add_symbols_to_table(symtab
);
3537 // Finalize symbols and check assertions.
3540 Script_sections::finalize_symbols(Symbol_table
* symtab
, const Layout
* layout
)
3542 if (!this->saw_sections_clause_
)
3544 uint64_t dot_value
= 0;
3545 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3546 p
!= this->sections_elements_
->end();
3548 (*p
)->finalize_symbols(symtab
, layout
, &dot_value
);
3551 // Return the name of the output section to use for an input file name
3552 // and section name.
3555 Script_sections::output_section_name(
3556 const char* file_name
,
3557 const char* section_name
,
3558 Output_section
*** output_section_slot
,
3559 Script_sections::Section_type
* psection_type
,
3562 for (Sections_elements::const_iterator p
= this->sections_elements_
->begin();
3563 p
!= this->sections_elements_
->end();
3566 const char* ret
= (*p
)->output_section_name(file_name
, section_name
,
3567 output_section_slot
,
3568 psection_type
, keep
);
3572 // The special name /DISCARD/ means that the input section
3573 // should be discarded.
3574 if (strcmp(ret
, "/DISCARD/") == 0)
3576 *output_section_slot
= NULL
;
3577 *psection_type
= Script_sections::ST_NONE
;
3584 // If we couldn't find a mapping for the name, the output section
3585 // gets the name of the input section.
3587 *output_section_slot
= NULL
;
3588 *psection_type
= Script_sections::ST_NONE
;
3591 return section_name
;
3594 // Place a marker for an orphan output section into the SECTIONS
3598 Script_sections::place_orphan(Output_section
* os
)
3600 Orphan_section_placement
* osp
= this->orphan_section_placement_
;
3603 // Initialize the Orphan_section_placement structure.
3604 osp
= new Orphan_section_placement();
3605 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3606 p
!= this->sections_elements_
->end();
3608 (*p
)->orphan_section_init(osp
, p
);
3609 gold_assert(!this->sections_elements_
->empty());
3610 Sections_elements::iterator last
= this->sections_elements_
->end();
3612 osp
->last_init(last
);
3613 this->orphan_section_placement_
= osp
;
3616 Orphan_output_section
* orphan
= new Orphan_output_section(os
);
3618 // Look for where to put ORPHAN.
3619 Sections_elements::iterator
* where
;
3620 if (osp
->find_place(os
, &where
))
3622 if ((**where
)->is_relro())
3625 os
->clear_is_relro();
3627 // We want to insert ORPHAN after *WHERE, and then update *WHERE
3628 // so that the next one goes after this one.
3629 Sections_elements::iterator p
= *where
;
3630 gold_assert(p
!= this->sections_elements_
->end());
3632 *where
= this->sections_elements_
->insert(p
, orphan
);
3636 os
->clear_is_relro();
3637 // We don't have a place to put this orphan section. Put it,
3638 // and all other sections like it, at the end, but before the
3639 // sections which always come at the end.
3640 Sections_elements::iterator last
= osp
->last_place();
3641 *where
= this->sections_elements_
->insert(last
, orphan
);
3644 if ((os
->flags() & elfcpp::SHF_ALLOC
) != 0)
3645 osp
->update_last_alloc(*where
);
3648 // Set the addresses of all the output sections. Walk through all the
3649 // elements, tracking the dot symbol. Apply assignments which set
3650 // absolute symbol values, in case they are used when setting dot.
3651 // Fill in data statement values. As we find output sections, set the
3652 // address, set the address of all associated input sections, and
3653 // update dot. Return the segment which should hold the file header
3654 // and segment headers, if any.
3657 Script_sections::set_section_addresses(Symbol_table
* symtab
, Layout
* layout
)
3659 gold_assert(this->saw_sections_clause_
);
3661 // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain
3662 // for our representation.
3663 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3664 p
!= this->sections_elements_
->end();
3667 Output_section_definition
* posd
;
3668 Section_constraint failed_constraint
= (*p
)->check_constraint(&posd
);
3669 if (failed_constraint
!= CONSTRAINT_NONE
)
3671 Sections_elements::iterator q
;
3672 for (q
= this->sections_elements_
->begin();
3673 q
!= this->sections_elements_
->end();
3678 if ((*q
)->alternate_constraint(posd
, failed_constraint
))
3683 if (q
== this->sections_elements_
->end())
3684 gold_error(_("no matching section constraint"));
3688 // Force the alignment of the first TLS section to be the maximum
3689 // alignment of all TLS sections.
3690 Output_section
* first_tls
= NULL
;
3691 uint64_t tls_align
= 0;
3692 for (Sections_elements::const_iterator p
= this->sections_elements_
->begin();
3693 p
!= this->sections_elements_
->end();
3696 Output_section
* os
= (*p
)->get_output_section();
3697 if (os
!= NULL
&& (os
->flags() & elfcpp::SHF_TLS
) != 0)
3699 if (first_tls
== NULL
)
3701 if (os
->addralign() > tls_align
)
3702 tls_align
= os
->addralign();
3705 if (first_tls
!= NULL
)
3706 first_tls
->set_addralign(tls_align
);
3708 // For a relocatable link, we implicitly set dot to zero.
3709 uint64_t dot_value
= 0;
3710 uint64_t dot_alignment
= 0;
3711 uint64_t load_address
= 0;
3713 // Check to see if we want to use any of -Ttext, -Tdata and -Tbss options
3714 // to set section addresses. If the script has any SEGMENT_START
3715 // expression, we do not set the section addresses.
3716 bool use_tsection_options
=
3717 (!this->saw_segment_start_expression_
3718 && (parameters
->options().user_set_Ttext()
3719 || parameters
->options().user_set_Tdata()
3720 || parameters
->options().user_set_Tbss()));
3722 for (Sections_elements::iterator p
= this->sections_elements_
->begin();
3723 p
!= this->sections_elements_
->end();
3726 Output_section
* os
= (*p
)->get_output_section();
3728 // Handle -Ttext, -Tdata and -Tbss options. We do this by looking for
3729 // the special sections by names and doing dot assignments.
3730 if (use_tsection_options
3732 && (os
->flags() & elfcpp::SHF_ALLOC
) != 0)
3734 uint64_t new_dot_value
= dot_value
;
3736 if (parameters
->options().user_set_Ttext()
3737 && strcmp(os
->name(), ".text") == 0)
3738 new_dot_value
= parameters
->options().Ttext();
3739 else if (parameters
->options().user_set_Tdata()
3740 && strcmp(os
->name(), ".data") == 0)
3741 new_dot_value
= parameters
->options().Tdata();
3742 else if (parameters
->options().user_set_Tbss()
3743 && strcmp(os
->name(), ".bss") == 0)
3744 new_dot_value
= parameters
->options().Tbss();
3746 // Update dot and load address if necessary.
3747 if (new_dot_value
< dot_value
)
3748 gold_error(_("dot may not move backward"));
3749 else if (new_dot_value
!= dot_value
)
3751 dot_value
= new_dot_value
;
3752 load_address
= new_dot_value
;
3756 (*p
)->set_section_addresses(symtab
, layout
, &dot_value
, &dot_alignment
,
3760 if (this->phdrs_elements_
!= NULL
)
3762 for (Phdrs_elements::iterator p
= this->phdrs_elements_
->begin();
3763 p
!= this->phdrs_elements_
->end();
3765 (*p
)->eval_load_address(symtab
, layout
);
3768 return this->create_segments(layout
, dot_alignment
);
3771 // Sort the sections in order to put them into segments.
3773 class Sort_output_sections
3776 Sort_output_sections(const Script_sections::Sections_elements
* elements
)
3777 : elements_(elements
)
3781 operator()(const Output_section
* os1
, const Output_section
* os2
) const;
3785 script_compare(const Output_section
* os1
, const Output_section
* os2
) const;
3788 const Script_sections::Sections_elements
* elements_
;
3792 Sort_output_sections::operator()(const Output_section
* os1
,
3793 const Output_section
* os2
) const
3795 // Sort first by the load address.
3796 uint64_t lma1
= (os1
->has_load_address()
3797 ? os1
->load_address()
3799 uint64_t lma2
= (os2
->has_load_address()
3800 ? os2
->load_address()
3805 // Then sort by the virtual address.
3806 if (os1
->address() != os2
->address())
3807 return os1
->address() < os2
->address();
3809 // If the linker script says which of these sections is first, go
3810 // with what it says.
3811 int i
= this->script_compare(os1
, os2
);
3815 // Sort PROGBITS before NOBITS.
3816 bool nobits1
= os1
->type() == elfcpp::SHT_NOBITS
;
3817 bool nobits2
= os2
->type() == elfcpp::SHT_NOBITS
;
3818 if (nobits1
!= nobits2
)
3821 // Sort PROGBITS TLS sections to the end, NOBITS TLS sections to the
3823 bool tls1
= (os1
->flags() & elfcpp::SHF_TLS
) != 0;
3824 bool tls2
= (os2
->flags() & elfcpp::SHF_TLS
) != 0;
3826 return nobits1
? tls1
: tls2
;
3828 // Sort non-NOLOAD before NOLOAD.
3829 if (os1
->is_noload() && !os2
->is_noload())
3831 if (!os1
->is_noload() && os2
->is_noload())
3834 // The sections seem practically identical. Sort by name to get a
3836 return os1
->name() < os2
->name();
3839 // Return -1 if OS1 comes before OS2 in ELEMENTS_, 1 if comes after, 0
3840 // if either OS1 or OS2 is not mentioned. This ensures that we keep
3841 // empty sections in the order in which they appear in a linker
3845 Sort_output_sections::script_compare(const Output_section
* os1
,
3846 const Output_section
* os2
) const
3848 if (this->elements_
== NULL
)
3851 bool found_os1
= false;
3852 bool found_os2
= false;
3853 for (Script_sections::Sections_elements::const_iterator
3854 p
= this->elements_
->begin();
3855 p
!= this->elements_
->end();
3858 if (os2
== (*p
)->get_output_section())
3864 else if (os1
== (*p
)->get_output_section())
3875 // Return whether OS is a BSS section. This is a SHT_NOBITS section.
3876 // We treat a section with the SHF_TLS flag set as taking up space
3877 // even if it is SHT_NOBITS (this is true of .tbss), as we allocate
3878 // space for them in the file.
3881 Script_sections::is_bss_section(const Output_section
* os
)
3883 return (os
->type() == elfcpp::SHT_NOBITS
3884 && (os
->flags() & elfcpp::SHF_TLS
) == 0);
3887 // Return the size taken by the file header and the program headers.
3890 Script_sections::total_header_size(Layout
* layout
) const
3892 size_t segment_count
= layout
->segment_count();
3893 size_t file_header_size
;
3894 size_t segment_headers_size
;
3895 if (parameters
->target().get_size() == 32)
3897 file_header_size
= elfcpp::Elf_sizes
<32>::ehdr_size
;
3898 segment_headers_size
= segment_count
* elfcpp::Elf_sizes
<32>::phdr_size
;
3900 else if (parameters
->target().get_size() == 64)
3902 file_header_size
= elfcpp::Elf_sizes
<64>::ehdr_size
;
3903 segment_headers_size
= segment_count
* elfcpp::Elf_sizes
<64>::phdr_size
;
3908 return file_header_size
+ segment_headers_size
;
3911 // Return the amount we have to subtract from the LMA to accommodate
3912 // headers of the given size. The complication is that the file
3913 // header have to be at the start of a page, as otherwise it will not
3914 // be at the start of the file.
3917 Script_sections::header_size_adjustment(uint64_t lma
,
3918 size_t sizeof_headers
) const
3920 const uint64_t abi_pagesize
= parameters
->target().abi_pagesize();
3921 uint64_t hdr_lma
= lma
- sizeof_headers
;
3922 hdr_lma
&= ~(abi_pagesize
- 1);
3923 return lma
- hdr_lma
;
3926 // Create the PT_LOAD segments when using a SECTIONS clause. Returns
3927 // the segment which should hold the file header and segment headers,
3931 Script_sections::create_segments(Layout
* layout
, uint64_t dot_alignment
)
3933 gold_assert(this->saw_sections_clause_
);
3935 if (parameters
->options().relocatable())
3938 if (this->saw_phdrs_clause())
3939 return create_segments_from_phdrs_clause(layout
, dot_alignment
);
3941 Layout::Section_list sections
;
3942 layout
->get_allocated_sections(§ions
);
3944 // Sort the sections by address.
3945 std::stable_sort(sections
.begin(), sections
.end(),
3946 Sort_output_sections(this->sections_elements_
));
3948 this->create_note_and_tls_segments(layout
, §ions
);
3950 // Walk through the sections adding them to PT_LOAD segments.
3951 const uint64_t abi_pagesize
= parameters
->target().abi_pagesize();
3952 Output_segment
* first_seg
= NULL
;
3953 Output_segment
* current_seg
= NULL
;
3954 bool is_current_seg_readonly
= true;
3955 uint64_t last_vma
= 0;
3956 uint64_t last_lma
= 0;
3957 uint64_t last_size
= 0;
3958 bool in_bss
= false;
3959 for (Layout::Section_list::iterator p
= sections
.begin();
3960 p
!= sections
.end();
3963 const uint64_t vma
= (*p
)->address();
3964 const uint64_t lma
= ((*p
)->has_load_address()
3965 ? (*p
)->load_address()
3967 const uint64_t size
= (*p
)->current_data_size();
3969 bool need_new_segment
;
3970 if (current_seg
== NULL
)
3971 need_new_segment
= true;
3972 else if (lma
- vma
!= last_lma
- last_vma
)
3974 // This section has a different LMA relationship than the
3975 // last one; we need a new segment.
3976 need_new_segment
= true;
3978 else if (align_address(last_lma
+ last_size
, abi_pagesize
)
3979 < align_address(lma
, abi_pagesize
))
3981 // Putting this section in the segment would require
3983 need_new_segment
= true;
3985 else if (in_bss
&& !is_bss_section(*p
))
3987 // A non-BSS section can not follow a BSS section in the
3989 need_new_segment
= true;
3991 else if (is_current_seg_readonly
3992 && ((*p
)->flags() & elfcpp::SHF_WRITE
) != 0
3993 && !parameters
->options().omagic())
3995 // Don't put a writable section in the same segment as a
3996 // non-writable section.
3997 need_new_segment
= true;
4001 // Otherwise, reuse the existing segment.
4002 need_new_segment
= false;
4005 elfcpp::Elf_Word seg_flags
=
4006 Layout::section_flags_to_segment((*p
)->flags());
4008 if (need_new_segment
)
4010 current_seg
= layout
->make_output_segment(elfcpp::PT_LOAD
,
4012 current_seg
->set_addresses(vma
, lma
);
4013 current_seg
->set_minimum_p_align(dot_alignment
);
4014 if (first_seg
== NULL
)
4015 first_seg
= current_seg
;
4016 is_current_seg_readonly
= true;
4020 current_seg
->add_output_section_to_load(layout
, *p
, seg_flags
);
4022 if (((*p
)->flags() & elfcpp::SHF_WRITE
) != 0)
4023 is_current_seg_readonly
= false;
4025 if (is_bss_section(*p
) && size
> 0)
4033 // An ELF program should work even if the program headers are not in
4034 // a PT_LOAD segment. However, it appears that the Linux kernel
4035 // does not set the AT_PHDR auxiliary entry in that case. It sets
4036 // the load address to p_vaddr - p_offset of the first PT_LOAD
4037 // segment. It then sets AT_PHDR to the load address plus the
4038 // offset to the program headers, e_phoff in the file header. This
4039 // fails when the program headers appear in the file before the
4040 // first PT_LOAD segment. Therefore, we always create a PT_LOAD
4041 // segment to hold the file header and the program headers. This is
4042 // effectively what the GNU linker does, and it is slightly more
4043 // efficient in any case. We try to use the first PT_LOAD segment
4044 // if we can, otherwise we make a new one.
4046 if (first_seg
== NULL
)
4049 // -n or -N mean that the program is not demand paged and there is
4050 // no need to put the program headers in a PT_LOAD segment.
4051 if (parameters
->options().nmagic() || parameters
->options().omagic())
4054 size_t sizeof_headers
= this->total_header_size(layout
);
4056 uint64_t vma
= first_seg
->vaddr();
4057 uint64_t lma
= first_seg
->paddr();
4059 uint64_t subtract
= this->header_size_adjustment(lma
, sizeof_headers
);
4061 if ((lma
& (abi_pagesize
- 1)) >= sizeof_headers
)
4063 first_seg
->set_addresses(vma
- subtract
, lma
- subtract
);
4067 // If there is no room to squeeze in the headers, then punt. The
4068 // resulting executable probably won't run on GNU/Linux, but we
4069 // trust that the user knows what they are doing.
4070 if (lma
< subtract
|| vma
< subtract
)
4073 // If memory regions have been specified and the address range
4074 // we are about to use is not contained within any region then
4075 // issue a warning message about the segment we are going to
4076 // create. It will be outside of any region and so possibly
4077 // using non-existent or protected memory. We test LMA rather
4078 // than VMA since we assume that the headers will never be
4080 if (this->memory_regions_
!= NULL
4081 && !this->block_in_region (NULL
, layout
, lma
- subtract
, subtract
))
4082 gold_warning(_("creating a segment to contain the file and program"
4083 " headers outside of any MEMORY region"));
4085 Output_segment
* load_seg
= layout
->make_output_segment(elfcpp::PT_LOAD
,
4087 load_seg
->set_addresses(vma
- subtract
, lma
- subtract
);
4092 // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS
4093 // segment if there are any SHT_TLS sections.
4096 Script_sections::create_note_and_tls_segments(
4098 const Layout::Section_list
* sections
)
4100 gold_assert(!this->saw_phdrs_clause());
4102 bool saw_tls
= false;
4103 for (Layout::Section_list::const_iterator p
= sections
->begin();
4104 p
!= sections
->end();
4107 if ((*p
)->type() == elfcpp::SHT_NOTE
)
4109 elfcpp::Elf_Word seg_flags
=
4110 Layout::section_flags_to_segment((*p
)->flags());
4111 Output_segment
* oseg
= layout
->make_output_segment(elfcpp::PT_NOTE
,
4113 oseg
->add_output_section_to_nonload(*p
, seg_flags
);
4115 // Incorporate any subsequent SHT_NOTE sections, in the
4116 // hopes that the script is sensible.
4117 Layout::Section_list::const_iterator pnext
= p
+ 1;
4118 while (pnext
!= sections
->end()
4119 && (*pnext
)->type() == elfcpp::SHT_NOTE
)
4121 seg_flags
= Layout::section_flags_to_segment((*pnext
)->flags());
4122 oseg
->add_output_section_to_nonload(*pnext
, seg_flags
);
4128 if (((*p
)->flags() & elfcpp::SHF_TLS
) != 0)
4131 gold_error(_("TLS sections are not adjacent"));
4133 elfcpp::Elf_Word seg_flags
=
4134 Layout::section_flags_to_segment((*p
)->flags());
4135 Output_segment
* oseg
= layout
->make_output_segment(elfcpp::PT_TLS
,
4137 oseg
->add_output_section_to_nonload(*p
, seg_flags
);
4139 Layout::Section_list::const_iterator pnext
= p
+ 1;
4140 while (pnext
!= sections
->end()
4141 && ((*pnext
)->flags() & elfcpp::SHF_TLS
) != 0)
4143 seg_flags
= Layout::section_flags_to_segment((*pnext
)->flags());
4144 oseg
->add_output_section_to_nonload(*pnext
, seg_flags
);
4152 // If we see a section named .interp then put the .interp section
4153 // in a PT_INTERP segment.
4154 // This is for GNU ld compatibility.
4155 if (strcmp((*p
)->name(), ".interp") == 0)
4157 elfcpp::Elf_Word seg_flags
=
4158 Layout::section_flags_to_segment((*p
)->flags());
4159 Output_segment
* oseg
= layout
->make_output_segment(elfcpp::PT_INTERP
,
4161 oseg
->add_output_section_to_nonload(*p
, seg_flags
);
4165 this->segments_created_
= true;
4168 // Add a program header. The PHDRS clause is syntactically distinct
4169 // from the SECTIONS clause, but we implement it with the SECTIONS
4170 // support because PHDRS is useless if there is no SECTIONS clause.
4173 Script_sections::add_phdr(const char* name
, size_t namelen
, unsigned int type
,
4174 bool includes_filehdr
, bool includes_phdrs
,
4175 bool is_flags_valid
, unsigned int flags
,
4176 Expression
* load_address
)
4178 if (this->phdrs_elements_
== NULL
)
4179 this->phdrs_elements_
= new Phdrs_elements();
4180 this->phdrs_elements_
->push_back(new Phdrs_element(name
, namelen
, type
,
4183 is_flags_valid
, flags
,
4187 // Return the number of segments we expect to create based on the
4188 // SECTIONS clause. This is used to implement SIZEOF_HEADERS.
4191 Script_sections::expected_segment_count(const Layout
* layout
) const
4193 // If we've already created the segments, we won't be adding any more.
4194 if (this->segments_created_
)
4197 if (this->saw_phdrs_clause())
4198 return this->phdrs_elements_
->size();
4200 Layout::Section_list sections
;
4201 layout
->get_allocated_sections(§ions
);
4203 // We assume that we will need two PT_LOAD segments.
4206 bool saw_note
= false;
4207 bool saw_tls
= false;
4208 bool saw_interp
= false;
4209 for (Layout::Section_list::const_iterator p
= sections
.begin();
4210 p
!= sections
.end();
4213 if ((*p
)->type() == elfcpp::SHT_NOTE
)
4215 // Assume that all note sections will fit into a single
4223 else if (((*p
)->flags() & elfcpp::SHF_TLS
) != 0)
4225 // There can only be one PT_TLS segment.
4232 else if (strcmp((*p
)->name(), ".interp") == 0)
4234 // There can only be one PT_INTERP segment.
4246 // Create the segments from a PHDRS clause. Return the segment which
4247 // should hold the file header and program headers, if any.
4250 Script_sections::create_segments_from_phdrs_clause(Layout
* layout
,
4251 uint64_t dot_alignment
)
4253 this->attach_sections_using_phdrs_clause(layout
);
4254 return this->set_phdrs_clause_addresses(layout
, dot_alignment
);
4257 // Create the segments from the PHDRS clause, and put the output
4258 // sections in them.
4261 Script_sections::attach_sections_using_phdrs_clause(Layout
* layout
)
4263 typedef std::map
<std::string
, Output_segment
*> Name_to_segment
;
4264 Name_to_segment name_to_segment
;
4265 for (Phdrs_elements::const_iterator p
= this->phdrs_elements_
->begin();
4266 p
!= this->phdrs_elements_
->end();
4268 name_to_segment
[(*p
)->name()] = (*p
)->create_segment(layout
);
4269 this->segments_created_
= true;
4271 // Walk through the output sections and attach them to segments.
4272 // Output sections in the script which do not list segments are
4273 // attached to the same set of segments as the immediately preceding
4276 String_list
* phdr_names
= NULL
;
4277 bool load_segments_only
= false;
4278 for (Sections_elements::const_iterator p
= this->sections_elements_
->begin();
4279 p
!= this->sections_elements_
->end();
4283 String_list
* old_phdr_names
= phdr_names
;
4284 Output_section
* os
= (*p
)->allocate_to_segment(&phdr_names
, &is_orphan
);
4288 elfcpp::Elf_Word seg_flags
=
4289 Layout::section_flags_to_segment(os
->flags());
4291 if (phdr_names
== NULL
)
4293 // Don't worry about empty orphan sections.
4294 if (is_orphan
&& os
->current_data_size() > 0)
4295 gold_error(_("allocated section %s not in any segment"),
4298 // To avoid later crashes drop this section into the first
4300 for (Phdrs_elements::const_iterator ppe
=
4301 this->phdrs_elements_
->begin();
4302 ppe
!= this->phdrs_elements_
->end();
4305 Output_segment
* oseg
= (*ppe
)->segment();
4306 if (oseg
->type() == elfcpp::PT_LOAD
)
4308 oseg
->add_output_section_to_load(layout
, os
, seg_flags
);
4316 // We see a list of segments names. Disable PT_LOAD segment only
4318 if (old_phdr_names
!= phdr_names
)
4319 load_segments_only
= false;
4321 // If this is an orphan section--one that was not explicitly
4322 // mentioned in the linker script--then it should not inherit
4323 // any segment type other than PT_LOAD. Otherwise, e.g., the
4324 // PT_INTERP segment will pick up following orphan sections,
4325 // which does not make sense. If this is not an orphan section,
4326 // we trust the linker script.
4329 // Enable PT_LOAD segments only filtering until we see another
4330 // list of segment names.
4331 load_segments_only
= true;
4334 bool in_load_segment
= false;
4335 for (String_list::const_iterator q
= phdr_names
->begin();
4336 q
!= phdr_names
->end();
4339 Name_to_segment::const_iterator r
= name_to_segment
.find(*q
);
4340 if (r
== name_to_segment
.end())
4341 gold_error(_("no segment %s"), q
->c_str());
4344 if (load_segments_only
4345 && r
->second
->type() != elfcpp::PT_LOAD
)
4348 if (r
->second
->type() != elfcpp::PT_LOAD
)
4349 r
->second
->add_output_section_to_nonload(os
, seg_flags
);
4352 r
->second
->add_output_section_to_load(layout
, os
, seg_flags
);
4353 if (in_load_segment
)
4354 gold_error(_("section in two PT_LOAD segments"));
4355 in_load_segment
= true;
4360 if (!in_load_segment
)
4361 gold_error(_("allocated section not in any PT_LOAD segment"));
4365 // Set the addresses for segments created from a PHDRS clause. Return
4366 // the segment which should hold the file header and program headers,
4370 Script_sections::set_phdrs_clause_addresses(Layout
* layout
,
4371 uint64_t dot_alignment
)
4373 Output_segment
* load_seg
= NULL
;
4374 for (Phdrs_elements::const_iterator p
= this->phdrs_elements_
->begin();
4375 p
!= this->phdrs_elements_
->end();
4378 // Note that we have to set the flags after adding the output
4379 // sections to the segment, as adding an output segment can
4380 // change the flags.
4381 (*p
)->set_flags_if_valid();
4383 Output_segment
* oseg
= (*p
)->segment();
4385 if (oseg
->type() != elfcpp::PT_LOAD
)
4387 // The addresses of non-PT_LOAD segments are set from the
4388 // PT_LOAD segments.
4389 if ((*p
)->has_load_address())
4390 gold_error(_("may only specify load address for PT_LOAD segment"));
4394 oseg
->set_minimum_p_align(dot_alignment
);
4396 // The output sections should have addresses from the SECTIONS
4397 // clause. The addresses don't have to be in order, so find the
4398 // one with the lowest load address. Use that to set the
4399 // address of the segment.
4401 Output_section
* osec
= oseg
->section_with_lowest_load_address();
4404 oseg
->set_addresses(0, 0);
4408 uint64_t vma
= osec
->address();
4409 uint64_t lma
= osec
->has_load_address() ? osec
->load_address() : vma
;
4411 // Override the load address of the section with the load
4412 // address specified for the segment.
4413 if ((*p
)->has_load_address())
4415 if (osec
->has_load_address())
4416 gold_warning(_("PHDRS load address overrides "
4417 "section %s load address"),
4420 lma
= (*p
)->load_address();
4423 bool headers
= (*p
)->includes_filehdr() && (*p
)->includes_phdrs();
4424 if (!headers
&& ((*p
)->includes_filehdr() || (*p
)->includes_phdrs()))
4426 // We could support this if we wanted to.
4427 gold_error(_("using only one of FILEHDR and PHDRS is "
4428 "not currently supported"));
4432 size_t sizeof_headers
= this->total_header_size(layout
);
4433 uint64_t subtract
= this->header_size_adjustment(lma
,
4435 if (lma
>= subtract
&& vma
>= subtract
)
4442 gold_error(_("sections loaded on first page without room "
4443 "for file and program headers "
4444 "are not supported"));
4447 if (load_seg
!= NULL
)
4448 gold_error(_("using FILEHDR and PHDRS on more than one "
4449 "PT_LOAD segment is not currently supported"));
4453 oseg
->set_addresses(vma
, lma
);
4459 // Add the file header and segment headers to non-load segments
4460 // specified in the PHDRS clause.
4463 Script_sections::put_headers_in_phdrs(Output_data
* file_header
,
4464 Output_data
* segment_headers
)
4466 gold_assert(this->saw_phdrs_clause());
4467 for (Phdrs_elements::iterator p
= this->phdrs_elements_
->begin();
4468 p
!= this->phdrs_elements_
->end();
4471 if ((*p
)->type() != elfcpp::PT_LOAD
)
4473 if ((*p
)->includes_phdrs())
4474 (*p
)->segment()->add_initial_output_data(segment_headers
);
4475 if ((*p
)->includes_filehdr())
4476 (*p
)->segment()->add_initial_output_data(file_header
);
4481 // Look for an output section by name and return the address, the load
4482 // address, the alignment, and the size. This is used when an
4483 // expression refers to an output section which was not actually
4484 // created. This returns true if the section was found, false
4488 Script_sections::get_output_section_info(const char* name
, uint64_t* address
,
4489 uint64_t* load_address
,
4490 uint64_t* addralign
,
4491 uint64_t* size
) const
4493 if (!this->saw_sections_clause_
)
4495 for (Sections_elements::const_iterator p
= this->sections_elements_
->begin();
4496 p
!= this->sections_elements_
->end();
4498 if ((*p
)->get_output_section_info(name
, address
, load_address
, addralign
,
4504 // Release all Output_segments. This remove all pointers to all
4508 Script_sections::release_segments()
4510 if (this->saw_phdrs_clause())
4512 for (Phdrs_elements::const_iterator p
= this->phdrs_elements_
->begin();
4513 p
!= this->phdrs_elements_
->end();
4515 (*p
)->release_segment();
4517 this->segments_created_
= false;
4520 // Print the SECTIONS clause to F for debugging.
4523 Script_sections::print(FILE* f
) const
4525 if (this->phdrs_elements_
!= NULL
)
4527 fprintf(f
, "PHDRS {\n");
4528 for (Phdrs_elements::const_iterator p
= this->phdrs_elements_
->begin();
4529 p
!= this->phdrs_elements_
->end();
4535 if (this->memory_regions_
!= NULL
)
4537 fprintf(f
, "MEMORY {\n");
4538 for (Memory_regions::const_iterator m
= this->memory_regions_
->begin();
4539 m
!= this->memory_regions_
->end();
4545 if (!this->saw_sections_clause_
)
4548 fprintf(f
, "SECTIONS {\n");
4550 for (Sections_elements::const_iterator p
= this->sections_elements_
->begin();
4551 p
!= this->sections_elements_
->end();
4558 } // End namespace gold.