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 the base to use for the PC value in an FDE when it is
280 // encoded using DW_EH_PE_datarel. This does not appear to be
281 // documented anywhere, but it is target specific. Any use of
282 // DW_EH_PE_datarel in gcc requires defining a special macro
283 // (ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX) to output the value.
285 ehframe_datarel_base() const
286 { return this->do_ehframe_datarel_base(); }
288 // Return true if a reference to SYM from a reloc of type R_TYPE
289 // means that the current function may call an object compiled
290 // without -fsplit-stack. SYM is known to be defined in an object
291 // compiled without -fsplit-stack.
293 is_call_to_non_split(const Symbol
* sym
, unsigned int r_type
) const
294 { return this->do_is_call_to_non_split(sym
, r_type
); }
296 // A function starts at OFFSET in section SHNDX in OBJECT. That
297 // function was compiled with -fsplit-stack, but it refers to a
298 // function which was compiled without -fsplit-stack. VIEW is a
299 // modifiable view of the section; VIEW_SIZE is the size of the
300 // view. The target has to adjust the function so that it allocates
303 calls_non_split(Relobj
* object
, unsigned int shndx
,
304 section_offset_type fnoffset
, section_size_type fnsize
,
305 unsigned char* view
, section_size_type view_size
,
306 std::string
* from
, std::string
* to
) const
308 this->do_calls_non_split(object
, shndx
, fnoffset
, fnsize
, view
, view_size
,
312 // Make an ELF object.
313 template<int size
, bool big_endian
>
315 make_elf_object(const std::string
& name
, Input_file
* input_file
,
316 off_t offset
, const elfcpp::Ehdr
<size
, big_endian
>& ehdr
)
317 { return this->do_make_elf_object(name
, input_file
, offset
, ehdr
); }
319 // Make an output section.
321 make_output_section(const char* name
, elfcpp::Elf_Word type
,
322 elfcpp::Elf_Xword flags
)
323 { return this->do_make_output_section(name
, type
, flags
); }
325 // Return true if target wants to perform relaxation.
329 // Run the dummy relaxation pass twice if relaxation debugging is enabled.
330 if (is_debugging_enabled(DEBUG_RELAXATION
))
333 return this->do_may_relax();
336 // Perform a relaxation pass. Return true if layout may be changed.
338 relax(int pass
, const Input_objects
* input_objects
, Symbol_table
* symtab
,
339 Layout
* layout
, const Task
* task
)
341 // Run the dummy relaxation pass twice if relaxation debugging is enabled.
342 if (is_debugging_enabled(DEBUG_RELAXATION
))
345 return this->do_relax(pass
, input_objects
, symtab
, layout
, task
);
348 // Return the target-specific name of attributes section. This is
349 // NULL if a target does not use attributes section or if it uses
350 // the default section name ".gnu.attributes".
352 attributes_section() const
353 { return this->pti_
->attributes_section
; }
355 // Return the vendor name of vendor attributes.
357 attributes_vendor() const
358 { return this->pti_
->attributes_vendor
; }
360 // Whether a section called NAME is an attribute section.
362 is_attributes_section(const char* name
) const
364 return ((this->pti_
->attributes_section
!= NULL
365 && strcmp(name
, this->pti_
->attributes_section
) == 0)
366 || strcmp(name
, ".gnu.attributes") == 0);
369 // Return a bit mask of argument types for attribute with TAG.
371 attribute_arg_type(int tag
) const
372 { return this->do_attribute_arg_type(tag
); }
374 // Return the attribute tag of the position NUM in the list of fixed
375 // attributes. Normally there is no reordering and
376 // attributes_order(NUM) == NUM.
378 attributes_order(int num
) const
379 { return this->do_attributes_order(num
); }
381 // When a target is selected as the default target, we call this method,
382 // which may be used for expensive, target-specific initialization.
384 select_as_default_target()
385 { this->do_select_as_default_target(); }
387 // Return the value to store in the EI_OSABI field in the ELF
391 { return this->osabi_
; }
393 // Set the value to store in the EI_OSABI field in the ELF header.
395 set_osabi(elfcpp::ELFOSABI osabi
)
396 { this->osabi_
= osabi
; }
399 // This struct holds the constant information for a child class. We
400 // use a struct to avoid the overhead of virtual function calls for
401 // simple information.
404 // Address size (32 or 64).
406 // Whether the target is big endian.
408 // The code to store in the e_machine field of the ELF header.
409 elfcpp::EM machine_code
;
410 // Whether this target has a specific make_symbol function.
411 bool has_make_symbol
;
412 // Whether this target has a specific resolve function.
414 // Whether this target has a specific code fill function.
416 // Whether an object file with no .note.GNU-stack sections implies
417 // that the stack should be executable.
418 bool is_default_stack_executable
;
419 // Whether a relocation to a merged section can be processed to
420 // retrieve the contents.
421 bool can_icf_inline_merge_sections
;
422 // Prefix character to strip when checking for wrapping.
424 // The default dynamic linker name.
425 const char* dynamic_linker
;
426 // The default text segment address.
427 uint64_t default_text_segment_address
;
428 // The ABI specified page size.
429 uint64_t abi_pagesize
;
430 // The common page size used by actual implementations.
431 uint64_t common_pagesize
;
432 // The special section index for small common symbols; SHN_UNDEF
434 elfcpp::Elf_Half small_common_shndx
;
435 // The special section index for large common symbols; SHN_UNDEF
437 elfcpp::Elf_Half large_common_shndx
;
438 // Section flags for small common section.
439 elfcpp::Elf_Xword small_common_section_flags
;
440 // Section flags for large common section.
441 elfcpp::Elf_Xword large_common_section_flags
;
442 // Name of attributes section if it is not ".gnu.attributes".
443 const char* attributes_section
;
444 // Vendor name of vendor attributes.
445 const char* attributes_vendor
;
448 Target(const Target_info
* pti
)
449 : pti_(pti
), processor_specific_flags_(0),
450 are_processor_specific_flags_set_(false), osabi_(elfcpp::ELFOSABI_NONE
)
453 // Virtual function which may be implemented by the child class.
455 do_new_output_section(Output_section
*) const
458 // Virtual function which may be implemented by the child class.
460 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*)
463 // Virtual function which may be implemented by the child class.
465 do_dynsym_value(const Symbol
*) const
466 { gold_unreachable(); }
468 // Virtual function which must be implemented by the child class if
471 do_code_fill(section_size_type
) const
472 { gold_unreachable(); }
474 // Virtual function which may be implemented by the child class.
476 do_is_defined_by_abi(const Symbol
*) const
479 // Adjust the output file header before it is written out. VIEW
480 // points to the header in external form. LEN is the length, and
481 // will be one of the values of elfcpp::Elf_sizes<size>::ehdr_size.
482 // By default, we set the EI_OSABI field if requested (in
485 do_adjust_elf_header(unsigned char*, int) const = 0;
487 // Virtual function which may be overridden by the child class.
489 do_is_local_label_name(const char*) const;
491 // Virtual function that must be overridden by a target which uses
492 // target specific relocations.
494 do_reloc_symbol_index(void*, unsigned int) const
495 { gold_unreachable(); }
497 // Virtual function that must be overridden by a target which uses
498 // target specific relocations.
500 do_reloc_addend(void*, unsigned int, uint64_t) const
501 { gold_unreachable(); }
503 // Virtual functions that must be overridden by a target that uses
504 // STT_GNU_IFUNC symbols.
506 do_plt_section_for_global(const Symbol
*) const
507 { gold_unreachable(); }
510 do_plt_section_for_local(const Relobj
*, unsigned int) const
511 { gold_unreachable(); }
513 // Virtual function which may be overriden by the child class.
515 do_can_check_for_function_pointers() const
518 // Virtual function which may be overridden by the child class. We
519 // recognize some default sections for which we don't care whether
520 // they have function pointers.
522 do_section_may_have_icf_unsafe_pointers(const char* section_name
) const
524 // We recognize sections for normal vtables, construction vtables and
526 return (!is_prefix_of(".rodata._ZTV", section_name
)
527 && !is_prefix_of(".data.rel.ro._ZTV", section_name
)
528 && !is_prefix_of(".rodata._ZTC", section_name
)
529 && !is_prefix_of(".data.rel.ro._ZTC", section_name
)
530 && !is_prefix_of(".eh_frame", section_name
));
534 do_ehframe_datarel_base() const
535 { gold_unreachable(); }
537 // Virtual function which may be overridden by the child class. The
538 // default implementation is that any function not defined by the
539 // ABI is a call to a non-split function.
541 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
543 // Virtual function which may be overridden by the child class.
545 do_calls_non_split(Relobj
* object
, unsigned int, section_offset_type
,
546 section_size_type
, unsigned char*, section_size_type
,
547 std::string
*, std::string
*) const;
549 // make_elf_object hooks. There are four versions of these for
550 // different address sizes and endianness.
552 // Set processor specific flags.
554 set_processor_specific_flags(elfcpp::Elf_Word flags
)
556 this->processor_specific_flags_
= flags
;
557 this->are_processor_specific_flags_set_
= true;
560 #ifdef HAVE_TARGET_32_LITTLE
561 // Virtual functions which may be overridden by the child class.
563 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
564 const elfcpp::Ehdr
<32, false>&);
567 #ifdef HAVE_TARGET_32_BIG
568 // Virtual functions which may be overridden by the child class.
570 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
571 const elfcpp::Ehdr
<32, true>&);
574 #ifdef HAVE_TARGET_64_LITTLE
575 // Virtual functions which may be overridden by the child class.
577 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
578 const elfcpp::Ehdr
<64, false>& ehdr
);
581 #ifdef HAVE_TARGET_64_BIG
582 // Virtual functions which may be overridden by the child class.
584 do_make_elf_object(const std::string
& name
, Input_file
* input_file
,
585 off_t offset
, const elfcpp::Ehdr
<64, true>& ehdr
);
588 // Virtual functions which may be overridden by the child class.
589 virtual Output_section
*
590 do_make_output_section(const char* name
, elfcpp::Elf_Word type
,
591 elfcpp::Elf_Xword flags
);
593 // Virtual function which may be overridden by the child class.
596 { return parameters
->options().relax(); }
598 // Virtual function which may be overridden by the child class.
600 do_relax(int, const Input_objects
*, Symbol_table
*, Layout
*, const Task
*)
603 // A function for targets to call. Return whether BYTES/LEN matches
604 // VIEW/VIEW_SIZE at OFFSET.
606 match_view(const unsigned char* view
, section_size_type view_size
,
607 section_offset_type offset
, const char* bytes
, size_t len
) const;
609 // Set the contents of a VIEW/VIEW_SIZE to nops starting at OFFSET
612 set_view_to_nop(unsigned char* view
, section_size_type view_size
,
613 section_offset_type offset
, size_t len
) const;
615 // This must be overridden by the child class if it has target-specific
616 // attributes subsection in the attribute section.
618 do_attribute_arg_type(int) const
619 { gold_unreachable(); }
621 // This may be overridden by the child class.
623 do_attributes_order(int num
) const
626 // This may be overridden by the child class.
628 do_select_as_default_target()
632 // The implementations of the four do_make_elf_object virtual functions are
633 // almost identical except for their sizes and endianness. We use a template.
634 // for their implementations.
635 template<int size
, bool big_endian
>
637 do_make_elf_object_implementation(const std::string
&, Input_file
*, off_t
,
638 const elfcpp::Ehdr
<size
, big_endian
>&);
640 Target(const Target
&);
641 Target
& operator=(const Target
&);
643 // The target information.
644 const Target_info
* pti_
;
645 // Processor-specific flags.
646 elfcpp::Elf_Word processor_specific_flags_
;
647 // Whether the processor-specific flags are set at least once.
648 bool are_processor_specific_flags_set_
;
649 // If not ELFOSABI_NONE, the value to put in the EI_OSABI field of
650 // the ELF header. This is handled at this level because it is
651 // OS-specific rather than processor-specific.
652 elfcpp::ELFOSABI osabi_
;
655 // The abstract class for a specific size and endianness of target.
656 // Each actual target implementation class should derive from an
657 // instantiation of Sized_target.
659 template<int size
, bool big_endian
>
660 class Sized_target
: public Target
663 // Make a new symbol table entry for the target. This should be
664 // overridden by a target which needs additional information in the
665 // symbol table. This will only be called if has_make_symbol()
667 virtual Sized_symbol
<size
>*
669 { gold_unreachable(); }
671 // Resolve a symbol for the target. This should be overridden by a
672 // target which needs to take special action. TO is the
673 // pre-existing symbol. SYM is the new symbol, seen in OBJECT.
674 // VERSION is the version of SYM. This will only be called if
675 // has_resolve() returns true.
677 resolve(Symbol
*, const elfcpp::Sym
<size
, big_endian
>&, Object
*,
679 { gold_unreachable(); }
681 // Process the relocs for a section, and record information of the
682 // mapping from source to destination sections. This mapping is later
683 // used to determine unreferenced garbage sections. This procedure is
684 // only called during garbage collection.
686 gc_process_relocs(Symbol_table
* symtab
,
688 Sized_relobj_file
<size
, big_endian
>* object
,
689 unsigned int data_shndx
,
690 unsigned int sh_type
,
691 const unsigned char* prelocs
,
693 Output_section
* output_section
,
694 bool needs_special_offset_handling
,
695 size_t local_symbol_count
,
696 const unsigned char* plocal_symbols
) = 0;
698 // Scan the relocs for a section, and record any information
699 // required for the symbol. SYMTAB is the symbol table. OBJECT is
700 // the object in which the section appears. DATA_SHNDX is the
701 // section index that these relocs apply to. SH_TYPE is the type of
702 // the relocation section, SHT_REL or SHT_RELA. PRELOCS points to
703 // the relocation data. RELOC_COUNT is the number of relocs.
704 // LOCAL_SYMBOL_COUNT is the number of local symbols.
705 // OUTPUT_SECTION is the output section.
706 // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets to the output
707 // sections are not mapped as usual. PLOCAL_SYMBOLS points to the
708 // local symbol data from OBJECT. GLOBAL_SYMBOLS is the array of
709 // pointers to the global symbol table from OBJECT.
711 scan_relocs(Symbol_table
* symtab
,
713 Sized_relobj_file
<size
, big_endian
>* object
,
714 unsigned int data_shndx
,
715 unsigned int sh_type
,
716 const unsigned char* prelocs
,
718 Output_section
* output_section
,
719 bool needs_special_offset_handling
,
720 size_t local_symbol_count
,
721 const unsigned char* plocal_symbols
) = 0;
723 // Relocate section data. SH_TYPE is the type of the relocation
724 // section, SHT_REL or SHT_RELA. PRELOCS points to the relocation
725 // information. RELOC_COUNT is the number of relocs.
726 // OUTPUT_SECTION is the output section.
727 // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets must be mapped
728 // to correspond to the output section. VIEW is a view into the
729 // output file holding the section contents, VIEW_ADDRESS is the
730 // virtual address of the view, and VIEW_SIZE is the size of the
731 // view. If NEEDS_SPECIAL_OFFSET_HANDLING is true, the VIEW_xx
732 // parameters refer to the complete output section data, not just
733 // the input section data.
735 relocate_section(const Relocate_info
<size
, big_endian
>*,
736 unsigned int sh_type
,
737 const unsigned char* prelocs
,
739 Output_section
* output_section
,
740 bool needs_special_offset_handling
,
742 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
743 section_size_type view_size
,
744 const Reloc_symbol_changes
*) = 0;
746 // Scan the relocs during a relocatable link. The parameters are
747 // like scan_relocs, with an additional Relocatable_relocs
748 // parameter, used to record the disposition of the relocs.
750 scan_relocatable_relocs(Symbol_table
* symtab
,
752 Sized_relobj_file
<size
, big_endian
>* object
,
753 unsigned int data_shndx
,
754 unsigned int sh_type
,
755 const unsigned char* prelocs
,
757 Output_section
* output_section
,
758 bool needs_special_offset_handling
,
759 size_t local_symbol_count
,
760 const unsigned char* plocal_symbols
,
761 Relocatable_relocs
*) = 0;
763 // Relocate a section during a relocatable link. The parameters are
764 // like relocate_section, with additional parameters for the view of
765 // the output reloc section.
767 relocate_for_relocatable(const Relocate_info
<size
, big_endian
>*,
768 unsigned int sh_type
,
769 const unsigned char* prelocs
,
771 Output_section
* output_section
,
772 off_t offset_in_output_section
,
773 const Relocatable_relocs
*,
775 typename
elfcpp::Elf_types
<size
>::Elf_Addr
777 section_size_type view_size
,
778 unsigned char* reloc_view
,
779 section_size_type reloc_view_size
) = 0;
781 // Perform target-specific processing in a relocatable link. This is
782 // only used if we use the relocation strategy RELOC_SPECIAL.
783 // RELINFO points to a Relocation_info structure. SH_TYPE is the relocation
784 // section type. PRELOC_IN points to the original relocation. RELNUM is
785 // the index number of the relocation in the relocation section.
786 // OUTPUT_SECTION is the output section to which the relocation is applied.
787 // OFFSET_IN_OUTPUT_SECTION is the offset of the relocation input section
788 // within the output section. VIEW points to the output view of the
789 // output section. VIEW_ADDRESS is output address of the view. VIEW_SIZE
790 // is the size of the output view and PRELOC_OUT points to the new
791 // relocation in the output object.
793 // A target only needs to override this if the generic code in
794 // target-reloc.h cannot handle some relocation types.
797 relocate_special_relocatable(const Relocate_info
<size
, big_endian
>*
799 unsigned int /* sh_type */,
800 const unsigned char* /* preloc_in */,
802 Output_section
* /* output_section */,
803 off_t
/* offset_in_output_section */,
804 unsigned char* /* view */,
805 typename
elfcpp::Elf_types
<size
>::Elf_Addr
807 section_size_type
/* view_size */,
808 unsigned char* /* preloc_out*/)
809 { gold_unreachable(); }
811 // Return the number of entries in the GOT. This is only used for
812 // laying out the incremental link info sections. A target needs
813 // to implement this to support incremental linking.
816 got_entry_count() const
817 { gold_unreachable(); }
819 // Return the number of entries in the PLT. This is only used for
820 // laying out the incremental link info sections. A target needs
821 // to implement this to support incremental linking.
824 plt_entry_count() const
825 { gold_unreachable(); }
827 // Return the offset of the first non-reserved PLT entry. This is
828 // only used for laying out the incremental link info sections.
829 // A target needs to implement this to support incremental linking.
832 first_plt_entry_offset() const
833 { gold_unreachable(); }
835 // Return the size of each PLT entry. This is only used for
836 // laying out the incremental link info sections. A target needs
837 // to implement this to support incremental linking.
840 plt_entry_size() const
841 { gold_unreachable(); }
843 // Create the GOT and PLT sections for an incremental update.
844 // A target needs to implement this to support incremental linking.
846 virtual Output_data_got
<size
, big_endian
>*
847 init_got_plt_for_update(Symbol_table
*,
849 unsigned int /* got_count */,
850 unsigned int /* plt_count */)
851 { gold_unreachable(); }
853 // Reserve a GOT entry for a local symbol, and regenerate any
854 // necessary dynamic relocations.
856 reserve_local_got_entry(unsigned int /* got_index */,
857 Sized_relobj
<size
, big_endian
>* /* obj */,
858 unsigned int /* r_sym */,
859 unsigned int /* got_type */)
860 { gold_unreachable(); }
862 // Reserve a GOT entry for a global symbol, and regenerate any
863 // necessary dynamic relocations.
865 reserve_global_got_entry(unsigned int /* got_index */, Symbol
* /* gsym */,
866 unsigned int /* got_type */)
867 { gold_unreachable(); }
869 // Register an existing PLT entry for a global symbol.
870 // A target needs to implement this to support incremental linking.
873 register_global_plt_entry(unsigned int /* plt_index */,
875 { gold_unreachable(); }
877 // Force a COPY relocation for a given symbol.
878 // A target needs to implement this to support incremental linking.
881 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
)
882 { gold_unreachable(); }
884 // Apply an incremental relocation.
887 apply_relocation(const Relocate_info
<size
, big_endian
>* /* relinfo */,
888 typename
elfcpp::Elf_types
<size
>::Elf_Addr
/* r_offset */,
889 unsigned int /* r_type */,
890 typename
elfcpp::Elf_types
<size
>::Elf_Swxword
/* r_addend */,
891 const Symbol
* /* gsym */,
892 unsigned char* /* view */,
893 typename
elfcpp::Elf_types
<size
>::Elf_Addr
/* address */,
894 section_size_type
/* view_size */)
895 { gold_unreachable(); }
898 Sized_target(const Target::Target_info
* pti
)
901 gold_assert(pti
->size
== size
);
902 gold_assert(pti
->is_big_endian
? big_endian
: !big_endian
);
905 // Set the EI_OSABI field if requested.
907 do_adjust_elf_header(unsigned char*, int) const;
910 } // End namespace gold.
912 #endif // !defined(GOLD_TARGET_H)