1 // target.h -- target support for gold -*- C++ -*-
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
23 // The abstract class Target is the interface for target specific
24 // support. It defines abstract methods which each target must
25 // implement. Typically there will be one target per processor, but
26 // in some cases it may be necessary to have subclasses.
28 // For speed and consistency we want to use inline functions to handle
29 // relocation processing. So besides implementations of the abstract
30 // methods, each target is expected to define a template
31 // specialization of the relocation functions.
38 #include "parameters.h"
46 template<int size
, bool big_endian
>
48 template<int size
, bool big_endian
>
49 class Sized_relobj_file
;
50 class Relocatable_relocs
;
51 template<int size
, bool big_endian
>
53 class Reloc_symbol_changes
;
59 template<int size
, bool big_endian
>
60 class Output_data_got
;
65 // The abstract class for target specific handling.
73 // Return the bit size that this target implements. This should
77 { return this->pti_
->size
; }
79 // Return whether this target is big-endian.
82 { return this->pti_
->is_big_endian
; }
84 // Machine code to store in e_machine field of ELF header.
87 { return this->pti_
->machine_code
; }
89 // Processor specific flags to store in e_flags field of ELF header.
91 processor_specific_flags() const
92 { return this->processor_specific_flags_
; }
94 // Whether processor specific flags are set at least once.
96 are_processor_specific_flags_set() const
97 { return this->are_processor_specific_flags_set_
; }
99 // Whether this target has a specific make_symbol function.
101 has_make_symbol() const
102 { return this->pti_
->has_make_symbol
; }
104 // Whether this target has a specific resolve function.
107 { return this->pti_
->has_resolve
; }
109 // Whether this target has a specific code fill function.
111 has_code_fill() const
112 { return this->pti_
->has_code_fill
; }
114 // Return the default name of the dynamic linker.
116 dynamic_linker() const
117 { return this->pti_
->dynamic_linker
; }
119 // Return the default address to use for the text segment.
121 default_text_segment_address() const
122 { return this->pti_
->default_text_segment_address
; }
124 // Return the ABI specified page size.
128 if (parameters
->options().max_page_size() > 0)
129 return parameters
->options().max_page_size();
131 return this->pti_
->abi_pagesize
;
134 // Return the common page size used on actual systems.
136 common_pagesize() const
138 if (parameters
->options().common_page_size() > 0)
139 return std::min(parameters
->options().common_page_size(),
140 this->abi_pagesize());
142 return std::min(this->pti_
->common_pagesize
,
143 this->abi_pagesize());
146 // If we see some object files with .note.GNU-stack sections, and
147 // some objects files without them, this returns whether we should
148 // consider the object files without them to imply that the stack
149 // should be executable.
151 is_default_stack_executable() const
152 { return this->pti_
->is_default_stack_executable
; }
154 // Return a character which may appear as a prefix for a wrap
155 // symbol. If this character appears, we strip it when checking for
156 // wrapping and add it back when forming the final symbol name.
157 // This should be '\0' if not special prefix is required, which is
161 { return this->pti_
->wrap_char
; }
163 // Return the special section index which indicates a small common
164 // symbol. This will return SHN_UNDEF if there are no small common
167 small_common_shndx() const
168 { return this->pti_
->small_common_shndx
; }
170 // Return values to add to the section flags for the section holding
171 // small common symbols.
173 small_common_section_flags() const
175 gold_assert(this->pti_
->small_common_shndx
!= elfcpp::SHN_UNDEF
);
176 return this->pti_
->small_common_section_flags
;
179 // Return the special section index which indicates a large common
180 // symbol. This will return SHN_UNDEF if there are no large common
183 large_common_shndx() const
184 { return this->pti_
->large_common_shndx
; }
186 // Return values to add to the section flags for the section holding
187 // large common symbols.
189 large_common_section_flags() const
191 gold_assert(this->pti_
->large_common_shndx
!= elfcpp::SHN_UNDEF
);
192 return this->pti_
->large_common_section_flags
;
195 // This hook is called when an output section is created.
197 new_output_section(Output_section
* os
) const
198 { this->do_new_output_section(os
); }
200 // This is called to tell the target to complete any sections it is
201 // handling. After this all sections must have their final size.
203 finalize_sections(Layout
* layout
, const Input_objects
* input_objects
,
204 Symbol_table
* symtab
)
205 { return this->do_finalize_sections(layout
, input_objects
, symtab
); }
207 // Return the value to use for a global symbol which needs a special
208 // value in the dynamic symbol table. This will only be called if
209 // the backend first calls symbol->set_needs_dynsym_value().
211 dynsym_value(const Symbol
* sym
) const
212 { return this->do_dynsym_value(sym
); }
214 // Return a string to use to fill out a code section. This is
215 // basically one or more NOPS which must fill out the specified
218 code_fill(section_size_type length
) const
219 { return this->do_code_fill(length
); }
221 // Return whether SYM is known to be defined by the ABI. This is
222 // used to avoid inappropriate warnings about undefined symbols.
224 is_defined_by_abi(const Symbol
* sym
) const
225 { return this->do_is_defined_by_abi(sym
); }
227 // Adjust the output file header before it is written out. VIEW
228 // points to the header in external form. LEN is the length.
230 adjust_elf_header(unsigned char* view
, int len
) const
231 { return this->do_adjust_elf_header(view
, len
); }
233 // Return whether NAME is a local label name. This is used to implement the
234 // --discard-locals options.
236 is_local_label_name(const char* name
) const
237 { return this->do_is_local_label_name(name
); }
239 // Get the symbol index to use for a target specific reloc.
241 reloc_symbol_index(void* arg
, unsigned int type
) const
242 { return this->do_reloc_symbol_index(arg
, type
); }
244 // Get the addend to use for a target specific reloc.
246 reloc_addend(void* arg
, unsigned int type
, uint64_t addend
) const
247 { return this->do_reloc_addend(arg
, type
, addend
); }
249 // Return the PLT section to use for a global symbol. This is used
250 // for STT_GNU_IFUNC symbols.
252 plt_section_for_global(const Symbol
* sym
) const
253 { return this->do_plt_section_for_global(sym
); }
255 // Return the PLT section to use for a local symbol. This is used
256 // for STT_GNU_IFUNC symbols.
258 plt_section_for_local(const Relobj
* object
, unsigned int symndx
) const
259 { return this->do_plt_section_for_local(object
, symndx
); }
261 // Return whether this target can use relocation types to determine
262 // if a function's address is taken.
264 can_check_for_function_pointers() const
265 { return this->do_can_check_for_function_pointers(); }
267 // Return whether a relocation to a merged section can be processed
268 // to retrieve the contents.
270 can_icf_inline_merge_sections () const
271 { return this->pti_
->can_icf_inline_merge_sections
; }
273 // Whether a section called SECTION_NAME may have function pointers to
274 // sections not eligible for safe ICF folding.
276 section_may_have_icf_unsafe_pointers(const char* section_name
) const
277 { return this->do_section_may_have_icf_unsafe_pointers(section_name
); }
279 // Return true if a reference to SYM from a reloc of type R_TYPE
280 // means that the current function may call an object compiled
281 // without -fsplit-stack. SYM is known to be defined in an object
282 // compiled without -fsplit-stack.
284 is_call_to_non_split(const Symbol
* sym
, unsigned int r_type
) const
285 { return this->do_is_call_to_non_split(sym
, r_type
); }
287 // A function starts at OFFSET in section SHNDX in OBJECT. That
288 // function was compiled with -fsplit-stack, but it refers to a
289 // function which was compiled without -fsplit-stack. VIEW is a
290 // modifiable view of the section; VIEW_SIZE is the size of the
291 // view. The target has to adjust the function so that it allocates
294 calls_non_split(Relobj
* object
, unsigned int shndx
,
295 section_offset_type fnoffset
, section_size_type fnsize
,
296 unsigned char* view
, section_size_type view_size
,
297 std::string
* from
, std::string
* to
) const
299 this->do_calls_non_split(object
, shndx
, fnoffset
, fnsize
, view
, view_size
,
303 // Make an ELF object.
304 template<int size
, bool big_endian
>
306 make_elf_object(const std::string
& name
, Input_file
* input_file
,
307 off_t offset
, const elfcpp::Ehdr
<size
, big_endian
>& ehdr
)
308 { return this->do_make_elf_object(name
, input_file
, offset
, ehdr
); }
310 // Make an output section.
312 make_output_section(const char* name
, elfcpp::Elf_Word type
,
313 elfcpp::Elf_Xword flags
)
314 { return this->do_make_output_section(name
, type
, flags
); }
316 // Return true if target wants to perform relaxation.
320 // Run the dummy relaxation pass twice if relaxation debugging is enabled.
321 if (is_debugging_enabled(DEBUG_RELAXATION
))
324 return this->do_may_relax();
327 // Perform a relaxation pass. Return true if layout may be changed.
329 relax(int pass
, const Input_objects
* input_objects
, Symbol_table
* symtab
,
330 Layout
* layout
, const Task
* task
)
332 // Run the dummy relaxation pass twice if relaxation debugging is enabled.
333 if (is_debugging_enabled(DEBUG_RELAXATION
))
336 return this->do_relax(pass
, input_objects
, symtab
, layout
, task
);
339 // Return the target-specific name of attributes section. This is
340 // NULL if a target does not use attributes section or if it uses
341 // the default section name ".gnu.attributes".
343 attributes_section() const
344 { return this->pti_
->attributes_section
; }
346 // Return the vendor name of vendor attributes.
348 attributes_vendor() const
349 { return this->pti_
->attributes_vendor
; }
351 // Whether a section called NAME is an attribute section.
353 is_attributes_section(const char* name
) const
355 return ((this->pti_
->attributes_section
!= NULL
356 && strcmp(name
, this->pti_
->attributes_section
) == 0)
357 || strcmp(name
, ".gnu.attributes") == 0);
360 // Return a bit mask of argument types for attribute with TAG.
362 attribute_arg_type(int tag
) const
363 { return this->do_attribute_arg_type(tag
); }
365 // Return the attribute tag of the position NUM in the list of fixed
366 // attributes. Normally there is no reordering and
367 // attributes_order(NUM) == NUM.
369 attributes_order(int num
) const
370 { return this->do_attributes_order(num
); }
372 // When a target is selected as the default target, we call this method,
373 // which may be used for expensive, target-specific initialization.
375 select_as_default_target()
376 { this->do_select_as_default_target(); }
378 // Return the value to store in the EI_OSABI field in the ELF
382 { return this->osabi_
; }
384 // Set the value to store in the EI_OSABI field in the ELF header.
386 set_osabi(elfcpp::ELFOSABI osabi
)
387 { this->osabi_
= osabi
; }
390 // This struct holds the constant information for a child class. We
391 // use a struct to avoid the overhead of virtual function calls for
392 // simple information.
395 // Address size (32 or 64).
397 // Whether the target is big endian.
399 // The code to store in the e_machine field of the ELF header.
400 elfcpp::EM machine_code
;
401 // Whether this target has a specific make_symbol function.
402 bool has_make_symbol
;
403 // Whether this target has a specific resolve function.
405 // Whether this target has a specific code fill function.
407 // Whether an object file with no .note.GNU-stack sections implies
408 // that the stack should be executable.
409 bool is_default_stack_executable
;
410 // Whether a relocation to a merged section can be processed to
411 // retrieve the contents.
412 bool can_icf_inline_merge_sections
;
413 // Prefix character to strip when checking for wrapping.
415 // The default dynamic linker name.
416 const char* dynamic_linker
;
417 // The default text segment address.
418 uint64_t default_text_segment_address
;
419 // The ABI specified page size.
420 uint64_t abi_pagesize
;
421 // The common page size used by actual implementations.
422 uint64_t common_pagesize
;
423 // The special section index for small common symbols; SHN_UNDEF
425 elfcpp::Elf_Half small_common_shndx
;
426 // The special section index for large common symbols; SHN_UNDEF
428 elfcpp::Elf_Half large_common_shndx
;
429 // Section flags for small common section.
430 elfcpp::Elf_Xword small_common_section_flags
;
431 // Section flags for large common section.
432 elfcpp::Elf_Xword large_common_section_flags
;
433 // Name of attributes section if it is not ".gnu.attributes".
434 const char* attributes_section
;
435 // Vendor name of vendor attributes.
436 const char* attributes_vendor
;
439 Target(const Target_info
* pti
)
440 : pti_(pti
), processor_specific_flags_(0),
441 are_processor_specific_flags_set_(false), osabi_(elfcpp::ELFOSABI_NONE
)
444 // Virtual function which may be implemented by the child class.
446 do_new_output_section(Output_section
*) const
449 // Virtual function which may be implemented by the child class.
451 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*)
454 // Virtual function which may be implemented by the child class.
456 do_dynsym_value(const Symbol
*) const
457 { gold_unreachable(); }
459 // Virtual function which must be implemented by the child class if
462 do_code_fill(section_size_type
) const
463 { gold_unreachable(); }
465 // Virtual function which may be implemented by the child class.
467 do_is_defined_by_abi(const Symbol
*) const
470 // Adjust the output file header before it is written out. VIEW
471 // points to the header in external form. LEN is the length, and
472 // will be one of the values of elfcpp::Elf_sizes<size>::ehdr_size.
473 // By default, we set the EI_OSABI field if requested (in
476 do_adjust_elf_header(unsigned char*, int) const = 0;
478 // Virtual function which may be overridden by the child class.
480 do_is_local_label_name(const char*) const;
482 // Virtual function that must be overridden by a target which uses
483 // target specific relocations.
485 do_reloc_symbol_index(void*, unsigned int) const
486 { gold_unreachable(); }
488 // Virtual function that must be overridden by a target which uses
489 // target specific relocations.
491 do_reloc_addend(void*, unsigned int, uint64_t) const
492 { gold_unreachable(); }
494 // Virtual functions that must be overridden by a target that uses
495 // STT_GNU_IFUNC symbols.
497 do_plt_section_for_global(const Symbol
*) const
498 { gold_unreachable(); }
501 do_plt_section_for_local(const Relobj
*, unsigned int) const
502 { gold_unreachable(); }
504 // Virtual function which may be overriden by the child class.
506 do_can_check_for_function_pointers() const
509 // Virtual function which may be overridden by the child class. We
510 // recognize some default sections for which we don't care whether
511 // they have function pointers.
513 do_section_may_have_icf_unsafe_pointers(const char* section_name
) const
515 // We recognize sections for normal vtables, construction vtables and
517 return (!is_prefix_of(".rodata._ZTV", section_name
)
518 && !is_prefix_of(".data.rel.ro._ZTV", section_name
)
519 && !is_prefix_of(".rodata._ZTC", section_name
)
520 && !is_prefix_of(".data.rel.ro._ZTC", section_name
)
521 && !is_prefix_of(".eh_frame", section_name
));
524 // Virtual function which may be overridden by the child class. The
525 // default implementation is that any function not defined by the
526 // ABI is a call to a non-split function.
528 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
530 // Virtual function which may be overridden by the child class.
532 do_calls_non_split(Relobj
* object
, unsigned int, section_offset_type
,
533 section_size_type
, unsigned char*, section_size_type
,
534 std::string
*, std::string
*) const;
536 // make_elf_object hooks. There are four versions of these for
537 // different address sizes and endianness.
539 // Set processor specific flags.
541 set_processor_specific_flags(elfcpp::Elf_Word flags
)
543 this->processor_specific_flags_
= flags
;
544 this->are_processor_specific_flags_set_
= true;
547 #ifdef HAVE_TARGET_32_LITTLE
548 // Virtual functions which may be overridden by the child class.
550 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
551 const elfcpp::Ehdr
<32, false>&);
554 #ifdef HAVE_TARGET_32_BIG
555 // Virtual functions which may be overridden by the child class.
557 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
558 const elfcpp::Ehdr
<32, true>&);
561 #ifdef HAVE_TARGET_64_LITTLE
562 // Virtual functions which may be overridden by the child class.
564 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
565 const elfcpp::Ehdr
<64, false>& ehdr
);
568 #ifdef HAVE_TARGET_64_BIG
569 // Virtual functions which may be overridden by the child class.
571 do_make_elf_object(const std::string
& name
, Input_file
* input_file
,
572 off_t offset
, const elfcpp::Ehdr
<64, true>& ehdr
);
575 // Virtual functions which may be overridden by the child class.
576 virtual Output_section
*
577 do_make_output_section(const char* name
, elfcpp::Elf_Word type
,
578 elfcpp::Elf_Xword flags
);
580 // Virtual function which may be overridden by the child class.
583 { return parameters
->options().relax(); }
585 // Virtual function which may be overridden by the child class.
587 do_relax(int, const Input_objects
*, Symbol_table
*, Layout
*, const Task
*)
590 // A function for targets to call. Return whether BYTES/LEN matches
591 // VIEW/VIEW_SIZE at OFFSET.
593 match_view(const unsigned char* view
, section_size_type view_size
,
594 section_offset_type offset
, const char* bytes
, size_t len
) const;
596 // Set the contents of a VIEW/VIEW_SIZE to nops starting at OFFSET
599 set_view_to_nop(unsigned char* view
, section_size_type view_size
,
600 section_offset_type offset
, size_t len
) const;
602 // This must be overridden by the child class if it has target-specific
603 // attributes subsection in the attribute section.
605 do_attribute_arg_type(int) const
606 { gold_unreachable(); }
608 // This may be overridden by the child class.
610 do_attributes_order(int num
) const
613 // This may be overridden by the child class.
615 do_select_as_default_target()
619 // The implementations of the four do_make_elf_object virtual functions are
620 // almost identical except for their sizes and endianness. We use a template.
621 // for their implementations.
622 template<int size
, bool big_endian
>
624 do_make_elf_object_implementation(const std::string
&, Input_file
*, off_t
,
625 const elfcpp::Ehdr
<size
, big_endian
>&);
627 Target(const Target
&);
628 Target
& operator=(const Target
&);
630 // The target information.
631 const Target_info
* pti_
;
632 // Processor-specific flags.
633 elfcpp::Elf_Word processor_specific_flags_
;
634 // Whether the processor-specific flags are set at least once.
635 bool are_processor_specific_flags_set_
;
636 // If not ELFOSABI_NONE, the value to put in the EI_OSABI field of
637 // the ELF header. This is handled at this level because it is
638 // OS-specific rather than processor-specific.
639 elfcpp::ELFOSABI osabi_
;
642 // The abstract class for a specific size and endianness of target.
643 // Each actual target implementation class should derive from an
644 // instantiation of Sized_target.
646 template<int size
, bool big_endian
>
647 class Sized_target
: public Target
650 // Make a new symbol table entry for the target. This should be
651 // overridden by a target which needs additional information in the
652 // symbol table. This will only be called if has_make_symbol()
654 virtual Sized_symbol
<size
>*
656 { gold_unreachable(); }
658 // Resolve a symbol for the target. This should be overridden by a
659 // target which needs to take special action. TO is the
660 // pre-existing symbol. SYM is the new symbol, seen in OBJECT.
661 // VERSION is the version of SYM. This will only be called if
662 // has_resolve() returns true.
664 resolve(Symbol
*, const elfcpp::Sym
<size
, big_endian
>&, Object
*,
666 { gold_unreachable(); }
668 // Process the relocs for a section, and record information of the
669 // mapping from source to destination sections. This mapping is later
670 // used to determine unreferenced garbage sections. This procedure is
671 // only called during garbage collection.
673 gc_process_relocs(Symbol_table
* symtab
,
675 Sized_relobj_file
<size
, big_endian
>* object
,
676 unsigned int data_shndx
,
677 unsigned int sh_type
,
678 const unsigned char* prelocs
,
680 Output_section
* output_section
,
681 bool needs_special_offset_handling
,
682 size_t local_symbol_count
,
683 const unsigned char* plocal_symbols
) = 0;
685 // Scan the relocs for a section, and record any information
686 // required for the symbol. SYMTAB is the symbol table. OBJECT is
687 // the object in which the section appears. DATA_SHNDX is the
688 // section index that these relocs apply to. SH_TYPE is the type of
689 // the relocation section, SHT_REL or SHT_RELA. PRELOCS points to
690 // the relocation data. RELOC_COUNT is the number of relocs.
691 // LOCAL_SYMBOL_COUNT is the number of local symbols.
692 // OUTPUT_SECTION is the output section.
693 // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets to the output
694 // sections are not mapped as usual. PLOCAL_SYMBOLS points to the
695 // local symbol data from OBJECT. GLOBAL_SYMBOLS is the array of
696 // pointers to the global symbol table from OBJECT.
698 scan_relocs(Symbol_table
* symtab
,
700 Sized_relobj_file
<size
, big_endian
>* object
,
701 unsigned int data_shndx
,
702 unsigned int sh_type
,
703 const unsigned char* prelocs
,
705 Output_section
* output_section
,
706 bool needs_special_offset_handling
,
707 size_t local_symbol_count
,
708 const unsigned char* plocal_symbols
) = 0;
710 // Relocate section data. SH_TYPE is the type of the relocation
711 // section, SHT_REL or SHT_RELA. PRELOCS points to the relocation
712 // information. RELOC_COUNT is the number of relocs.
713 // OUTPUT_SECTION is the output section.
714 // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets must be mapped
715 // to correspond to the output section. VIEW is a view into the
716 // output file holding the section contents, VIEW_ADDRESS is the
717 // virtual address of the view, and VIEW_SIZE is the size of the
718 // view. If NEEDS_SPECIAL_OFFSET_HANDLING is true, the VIEW_xx
719 // parameters refer to the complete output section data, not just
720 // the input section data.
722 relocate_section(const Relocate_info
<size
, big_endian
>*,
723 unsigned int sh_type
,
724 const unsigned char* prelocs
,
726 Output_section
* output_section
,
727 bool needs_special_offset_handling
,
729 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
730 section_size_type view_size
,
731 const Reloc_symbol_changes
*) = 0;
733 // Scan the relocs during a relocatable link. The parameters are
734 // like scan_relocs, with an additional Relocatable_relocs
735 // parameter, used to record the disposition of the relocs.
737 scan_relocatable_relocs(Symbol_table
* symtab
,
739 Sized_relobj_file
<size
, big_endian
>* object
,
740 unsigned int data_shndx
,
741 unsigned int sh_type
,
742 const unsigned char* prelocs
,
744 Output_section
* output_section
,
745 bool needs_special_offset_handling
,
746 size_t local_symbol_count
,
747 const unsigned char* plocal_symbols
,
748 Relocatable_relocs
*) = 0;
750 // Relocate a section during a relocatable link. The parameters are
751 // like relocate_section, with additional parameters for the view of
752 // the output reloc section.
754 relocate_for_relocatable(const Relocate_info
<size
, big_endian
>*,
755 unsigned int sh_type
,
756 const unsigned char* prelocs
,
758 Output_section
* output_section
,
759 off_t offset_in_output_section
,
760 const Relocatable_relocs
*,
762 typename
elfcpp::Elf_types
<size
>::Elf_Addr
764 section_size_type view_size
,
765 unsigned char* reloc_view
,
766 section_size_type reloc_view_size
) = 0;
768 // Perform target-specific processing in a relocatable link. This is
769 // only used if we use the relocation strategy RELOC_SPECIAL.
770 // RELINFO points to a Relocation_info structure. SH_TYPE is the relocation
771 // section type. PRELOC_IN points to the original relocation. RELNUM is
772 // the index number of the relocation in the relocation section.
773 // OUTPUT_SECTION is the output section to which the relocation is applied.
774 // OFFSET_IN_OUTPUT_SECTION is the offset of the relocation input section
775 // within the output section. VIEW points to the output view of the
776 // output section. VIEW_ADDRESS is output address of the view. VIEW_SIZE
777 // is the size of the output view and PRELOC_OUT points to the new
778 // relocation in the output object.
780 // A target only needs to override this if the generic code in
781 // target-reloc.h cannot handle some relocation types.
784 relocate_special_relocatable(const Relocate_info
<size
, big_endian
>*
786 unsigned int /* sh_type */,
787 const unsigned char* /* preloc_in */,
789 Output_section
* /* output_section */,
790 off_t
/* offset_in_output_section */,
791 unsigned char* /* view */,
792 typename
elfcpp::Elf_types
<size
>::Elf_Addr
794 section_size_type
/* view_size */,
795 unsigned char* /* preloc_out*/)
796 { gold_unreachable(); }
798 // Return the number of entries in the GOT. This is only used for
799 // laying out the incremental link info sections. A target needs
800 // to implement this to support incremental linking.
803 got_entry_count() const
804 { gold_unreachable(); }
806 // Return the number of entries in the PLT. This is only used for
807 // laying out the incremental link info sections. A target needs
808 // to implement this to support incremental linking.
811 plt_entry_count() const
812 { gold_unreachable(); }
814 // Return the offset of the first non-reserved PLT entry. This is
815 // only used for laying out the incremental link info sections.
816 // A target needs to implement this to support incremental linking.
819 first_plt_entry_offset() const
820 { gold_unreachable(); }
822 // Return the size of each PLT entry. This is only used for
823 // laying out the incremental link info sections. A target needs
824 // to implement this to support incremental linking.
827 plt_entry_size() const
828 { gold_unreachable(); }
830 // Create the GOT and PLT sections for an incremental update.
831 // A target needs to implement this to support incremental linking.
833 virtual Output_data_got
<size
, big_endian
>*
834 init_got_plt_for_update(Symbol_table
*,
836 unsigned int /* got_count */,
837 unsigned int /* plt_count */)
838 { gold_unreachable(); }
840 // Reserve a GOT entry for a local symbol, and regenerate any
841 // necessary dynamic relocations.
843 reserve_local_got_entry(unsigned int /* got_index */,
844 Sized_relobj
<size
, big_endian
>* /* obj */,
845 unsigned int /* r_sym */,
846 unsigned int /* got_type */)
847 { gold_unreachable(); }
849 // Reserve a GOT entry for a global symbol, and regenerate any
850 // necessary dynamic relocations.
852 reserve_global_got_entry(unsigned int /* got_index */, Symbol
* /* gsym */,
853 unsigned int /* got_type */)
854 { gold_unreachable(); }
856 // Register an existing PLT entry for a global symbol.
857 // A target needs to implement this to support incremental linking.
860 register_global_plt_entry(unsigned int /* plt_index */,
862 { gold_unreachable(); }
864 // Force a COPY relocation for a given symbol.
865 // A target needs to implement this to support incremental linking.
868 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
)
869 { gold_unreachable(); }
871 // Apply an incremental relocation.
874 apply_relocation(const Relocate_info
<size
, big_endian
>* /* relinfo */,
875 typename
elfcpp::Elf_types
<size
>::Elf_Addr
/* r_offset */,
876 unsigned int /* r_type */,
877 typename
elfcpp::Elf_types
<size
>::Elf_Swxword
/* r_addend */,
878 const Symbol
* /* gsym */,
879 unsigned char* /* view */,
880 typename
elfcpp::Elf_types
<size
>::Elf_Addr
/* address */,
881 section_size_type
/* view_size */)
882 { gold_unreachable(); }
885 Sized_target(const Target::Target_info
* pti
)
888 gold_assert(pti
->size
== size
);
889 gold_assert(pti
->is_big_endian
? big_endian
: !big_endian
);
892 // Set the EI_OSABI field if requested.
894 do_adjust_elf_header(unsigned char*, int) const;
897 } // End namespace gold.
899 #endif // !defined(GOLD_TARGET_H)