1 // arm.cc -- arm target support for gold.
3 // Copyright 2009 Free Software Foundation, Inc.
4 // Written by Doug Kwan <dougkwan@google.com> based on the i386 code
5 // by Ian Lance Taylor <iant@google.com>.
6 // This file also contains borrowed and adapted code from
9 // This file is part of gold.
11 // This program is free software; you can redistribute it and/or modify
12 // it under the terms of the GNU General Public License as published by
13 // the Free Software Foundation; either version 3 of the License, or
14 // (at your option) any later version.
16 // This program is distributed in the hope that it will be useful,
17 // but WITHOUT ANY WARRANTY; without even the implied warranty of
18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 // GNU General Public License for more details.
21 // You should have received a copy of the GNU General Public License
22 // along with this program; if not, write to the Free Software
23 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
24 // MA 02110-1301, USA.
35 #include "parameters.h"
42 #include "copy-relocs.h"
44 #include "target-reloc.h"
45 #include "target-select.h"
49 #include "attributes.h"
56 template<bool big_endian>
57 class Output_data_plt_arm;
59 template<bool big_endian>
62 template<bool big_endian>
63 class Arm_input_section;
65 template<bool big_endian>
66 class Arm_output_section;
68 template<bool big_endian>
71 template<bool big_endian>
75 typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address;
77 // Maximum branch offsets for ARM, THUMB and THUMB2.
78 const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8);
79 const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8);
80 const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4);
81 const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4);
82 const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
83 const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
85 // The arm target class.
87 // This is a very simple port of gold for ARM-EABI. It is intended for
88 // supporting Android only for the time being. Only these relocation types
117 // R_ARM_THM_MOVW_ABS_NC
118 // R_ARM_THM_MOVT_ABS
119 // R_ARM_MOVW_PREL_NC
121 // R_ARM_THM_MOVW_PREL_NC
122 // R_ARM_THM_MOVT_PREL
125 // - Support more relocation types as needed.
126 // - Make PLTs more flexible for different architecture features like
128 // There are probably a lot more.
130 // Instruction template class. This class is similar to the insn_sequence
131 // struct in bfd/elf32-arm.c.
136 // Types of instruction templates.
145 // Factory methods to create instrunction templates in different formats.
147 static const Insn_template
148 thumb16_insn(uint32_t data)
149 { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
151 // A bit of a hack. A Thumb conditional branch, in which the proper
152 // condition is inserted when we build the stub.
153 static const Insn_template
154 thumb16_bcond_insn(uint32_t data)
155 { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 1); }
157 static const Insn_template
158 thumb32_insn(uint32_t data)
159 { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); }
161 static const Insn_template
162 thumb32_b_insn(uint32_t data, int reloc_addend)
164 return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24,
168 static const Insn_template
169 arm_insn(uint32_t data)
170 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); }
172 static const Insn_template
173 arm_rel_insn(unsigned data, int reloc_addend)
174 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); }
176 static const Insn_template
177 data_word(unsigned data, unsigned int r_type, int reloc_addend)
178 { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); }
180 // Accessors. This class is used for read-only objects so no modifiers
185 { return this->data_; }
187 // Return the instruction sequence type of this.
190 { return this->type_; }
192 // Return the ARM relocation type of this.
195 { return this->r_type_; }
199 { return this->reloc_addend_; }
201 // Return size of instrunction template in bytes.
205 // Return byte-alignment of instrunction template.
210 // We make the constructor private to ensure that only the factory
213 Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend)
214 : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend)
217 // Instruction specific data. This is used to store information like
218 // some of the instruction bits.
220 // Instruction template type.
222 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
223 unsigned int r_type_;
224 // Relocation addend.
225 int32_t reloc_addend_;
228 // Macro for generating code to stub types. One entry per long/short
232 DEF_STUB(long_branch_any_any) \
233 DEF_STUB(long_branch_v4t_arm_thumb) \
234 DEF_STUB(long_branch_thumb_only) \
235 DEF_STUB(long_branch_v4t_thumb_thumb) \
236 DEF_STUB(long_branch_v4t_thumb_arm) \
237 DEF_STUB(short_branch_v4t_thumb_arm) \
238 DEF_STUB(long_branch_any_arm_pic) \
239 DEF_STUB(long_branch_any_thumb_pic) \
240 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
241 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
242 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
243 DEF_STUB(long_branch_thumb_only_pic) \
244 DEF_STUB(a8_veneer_b_cond) \
245 DEF_STUB(a8_veneer_b) \
246 DEF_STUB(a8_veneer_bl) \
247 DEF_STUB(a8_veneer_blx)
251 #define DEF_STUB(x) arm_stub_##x,
257 // First reloc stub type.
258 arm_stub_reloc_first = arm_stub_long_branch_any_any,
259 // Last reloc stub type.
260 arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic,
262 // First Cortex-A8 stub type.
263 arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond,
264 // Last Cortex-A8 stub type.
265 arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
268 arm_stub_type_last = arm_stub_a8_veneer_blx
272 // Stub template class. Templates are meant to be read-only objects.
273 // A stub template for a stub type contains all read-only attributes
274 // common to all stubs of the same type.
279 Stub_template(Stub_type, const Insn_template*, size_t);
287 { return this->type_; }
289 // Return an array of instruction templates.
292 { return this->insns_; }
294 // Return size of template in number of instructions.
297 { return this->insn_count_; }
299 // Return size of template in bytes.
302 { return this->size_; }
304 // Return alignment of the stub template.
307 { return this->alignment_; }
309 // Return whether entry point is in thumb mode.
311 entry_in_thumb_mode() const
312 { return this->entry_in_thumb_mode_; }
314 // Return number of relocations in this template.
317 { return this->relocs_.size(); }
319 // Return index of the I-th instruction with relocation.
321 reloc_insn_index(size_t i) const
323 gold_assert(i < this->relocs_.size());
324 return this->relocs_[i].first;
327 // Return the offset of the I-th instruction with relocation from the
328 // beginning of the stub.
330 reloc_offset(size_t i) const
332 gold_assert(i < this->relocs_.size());
333 return this->relocs_[i].second;
337 // This contains information about an instruction template with a relocation
338 // and its offset from start of stub.
339 typedef std::pair<size_t, section_size_type> Reloc;
341 // A Stub_template may not be copied. We want to share templates as much
343 Stub_template(const Stub_template&);
344 Stub_template& operator=(const Stub_template&);
348 // Points to an array of Insn_templates.
349 const Insn_template* insns_;
350 // Number of Insn_templates in insns_[].
352 // Size of templated instructions in bytes.
354 // Alignment of templated instructions.
356 // Flag to indicate if entry is in thumb mode.
357 bool entry_in_thumb_mode_;
358 // A table of reloc instruction indices and offsets. We can find these by
359 // looking at the instruction templates but we pre-compute and then stash
360 // them here for speed.
361 std::vector<Reloc> relocs_;
365 // A class for code stubs. This is a base class for different type of
366 // stubs used in the ARM target.
372 static const section_offset_type invalid_offset =
373 static_cast<section_offset_type>(-1);
376 Stub(const Stub_template* stub_template)
377 : stub_template_(stub_template), offset_(invalid_offset)
384 // Return the stub template.
386 stub_template() const
387 { return this->stub_template_; }
389 // Return offset of code stub from beginning of its containing stub table.
393 gold_assert(this->offset_ != invalid_offset);
394 return this->offset_;
397 // Set offset of code stub from beginning of its containing stub table.
399 set_offset(section_offset_type offset)
400 { this->offset_ = offset; }
402 // Return the relocation target address of the i-th relocation in the
403 // stub. This must be defined in a child class.
405 reloc_target(size_t i)
406 { return this->do_reloc_target(i); }
408 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
410 write(unsigned char* view, section_size_type view_size, bool big_endian)
411 { this->do_write(view, view_size, big_endian); }
414 // This must be defined in the child class.
416 do_reloc_target(size_t) = 0;
418 // This must be defined in the child class.
420 do_write(unsigned char*, section_size_type, bool) = 0;
424 const Stub_template* stub_template_;
425 // Offset within the section of containing this stub.
426 section_offset_type offset_;
429 // Reloc stub class. These are stubs we use to fix up relocation because
430 // of limited branch ranges.
432 class Reloc_stub : public Stub
435 static const unsigned int invalid_index = static_cast<unsigned int>(-1);
436 // We assume we never jump to this address.
437 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
439 // Return destination address.
441 destination_address() const
443 gold_assert(this->destination_address_ != this->invalid_address);
444 return this->destination_address_;
447 // Set destination address.
449 set_destination_address(Arm_address address)
451 gold_assert(address != this->invalid_address);
452 this->destination_address_ = address;
455 // Reset destination address.
457 reset_destination_address()
458 { this->destination_address_ = this->invalid_address; }
460 // Determine stub type for a branch of a relocation of R_TYPE going
461 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
462 // the branch target is a thumb instruction. TARGET is used for look
463 // up ARM-specific linker settings.
465 stub_type_for_reloc(unsigned int r_type, Arm_address branch_address,
466 Arm_address branch_target, bool target_is_thumb);
468 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
469 // and an addend. Since we treat global and local symbol differently, we
470 // use a Symbol object for a global symbol and a object-index pair for
475 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
476 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
477 // and R_SYM must not be invalid_index.
478 Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj,
479 unsigned int r_sym, int32_t addend)
480 : stub_type_(stub_type), addend_(addend)
484 this->r_sym_ = Reloc_stub::invalid_index;
485 this->u_.symbol = symbol;
489 gold_assert(relobj != NULL && r_sym != invalid_index);
490 this->r_sym_ = r_sym;
491 this->u_.relobj = relobj;
498 // Accessors: Keys are meant to be read-only object so no modifiers are
504 { return this->stub_type_; }
506 // Return the local symbol index or invalid_index.
509 { return this->r_sym_; }
511 // Return the symbol if there is one.
514 { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
516 // Return the relobj if there is one.
519 { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
521 // Whether this equals to another key k.
523 eq(const Key& k) const
525 return ((this->stub_type_ == k.stub_type_)
526 && (this->r_sym_ == k.r_sym_)
527 && ((this->r_sym_ != Reloc_stub::invalid_index)
528 ? (this->u_.relobj == k.u_.relobj)
529 : (this->u_.symbol == k.u_.symbol))
530 && (this->addend_ == k.addend_));
533 // Return a hash value.
537 return (this->stub_type_
539 ^ gold::string_hash<char>(
540 (this->r_sym_ != Reloc_stub::invalid_index)
541 ? this->u_.relobj->name().c_str()
542 : this->u_.symbol->name())
546 // Functors for STL associative containers.
550 operator()(const Key& k) const
551 { return k.hash_value(); }
557 operator()(const Key& k1, const Key& k2) const
558 { return k1.eq(k2); }
561 // Name of key. This is mainly for debugging.
567 Stub_type stub_type_;
568 // If this is a local symbol, this is the index in the defining object.
569 // Otherwise, it is invalid_index for a global symbol.
571 // If r_sym_ is invalid index. This points to a global symbol.
572 // Otherwise, this points a relobj. We used the unsized and target
573 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
574 // Arm_relobj. This is done to avoid making the stub class a template
575 // as most of the stub machinery is endianity-neutral. However, it
576 // may require a bit of casting done by users of this class.
579 const Symbol* symbol;
580 const Relobj* relobj;
582 // Addend associated with a reloc.
587 // Reloc_stubs are created via a stub factory. So these are protected.
588 Reloc_stub(const Stub_template* stub_template)
589 : Stub(stub_template), destination_address_(invalid_address)
595 friend class Stub_factory;
598 // Return the relocation target address of the i-th relocation in the
601 do_reloc_target(size_t i)
603 // All reloc stub have only one relocation.
605 return this->destination_address_;
608 // A template to implement do_write below.
609 template<bool big_endian>
611 do_fixed_endian_write(unsigned char*, section_size_type);
615 do_write(unsigned char* view, section_size_type view_size, bool big_endian);
617 // Address of destination.
618 Arm_address destination_address_;
621 // Stub factory class.
626 // Return the unique instance of this class.
627 static const Stub_factory&
630 static Stub_factory singleton;
634 // Make a relocation stub.
636 make_reloc_stub(Stub_type stub_type) const
638 gold_assert(stub_type >= arm_stub_reloc_first
639 && stub_type <= arm_stub_reloc_last);
640 return new Reloc_stub(this->stub_templates_[stub_type]);
644 // Constructor and destructor are protected since we only return a single
645 // instance created in Stub_factory::get_instance().
649 // A Stub_factory may not be copied since it is a singleton.
650 Stub_factory(const Stub_factory&);
651 Stub_factory& operator=(Stub_factory&);
653 // Stub templates. These are initialized in the constructor.
654 const Stub_template* stub_templates_[arm_stub_type_last+1];
657 // A class to hold stubs for the ARM target.
659 template<bool big_endian>
660 class Stub_table : public Output_data
663 Stub_table(Arm_input_section<big_endian>* owner)
664 : Output_data(), addralign_(1), owner_(owner), has_been_changed_(false),
671 // Owner of this stub table.
672 Arm_input_section<big_endian>*
674 { return this->owner_; }
676 // Whether this stub table is empty.
679 { return this->reloc_stubs_.empty(); }
681 // Whether this has been changed.
683 has_been_changed() const
684 { return this->has_been_changed_; }
686 // Set the has-been-changed flag.
688 set_has_been_changed(bool value)
689 { this->has_been_changed_ = value; }
691 // Return the current data size.
693 current_data_size() const
694 { return this->current_data_size_for_child(); }
696 // Add a STUB with using KEY. Caller is reponsible for avoid adding
697 // if already a STUB with the same key has been added.
699 add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key);
701 // Look up a relocation stub using KEY. Return NULL if there is none.
703 find_reloc_stub(const Reloc_stub::Key& key) const
705 typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
706 return (p != this->reloc_stubs_.end()) ? p->second : NULL;
709 // Relocate stubs in this stub table.
711 relocate_stubs(const Relocate_info<32, big_endian>*,
712 Target_arm<big_endian>*, Output_section*,
713 unsigned char*, Arm_address, section_size_type);
716 // Write out section contents.
718 do_write(Output_file*);
720 // Return the required alignment.
723 { return this->addralign_; }
725 // Finalize data size.
727 set_final_data_size()
728 { this->set_data_size(this->current_data_size_for_child()); }
730 // Reset address and file offset.
732 do_reset_address_and_file_offset();
735 // Unordered map of stubs.
737 Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
738 Reloc_stub::Key::equal_to>
743 // Owner of this stub table.
744 Arm_input_section<big_endian>* owner_;
745 // This is set to true during relaxiong if the size of the stub table
747 bool has_been_changed_;
748 // The relocation stubs.
749 Reloc_stub_map reloc_stubs_;
752 // A class to wrap an ordinary input section containing executable code.
754 template<bool big_endian>
755 class Arm_input_section : public Output_relaxed_input_section
758 Arm_input_section(Relobj* relobj, unsigned int shndx)
759 : Output_relaxed_input_section(relobj, shndx, 1),
760 original_addralign_(1), original_size_(0), stub_table_(NULL)
770 // Whether this is a stub table owner.
772 is_stub_table_owner() const
773 { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
775 // Return the stub table.
776 Stub_table<big_endian>*
778 { return this->stub_table_; }
780 // Set the stub_table.
782 set_stub_table(Stub_table<big_endian>* stub_table)
783 { this->stub_table_ = stub_table; }
785 // Downcast a base pointer to an Arm_input_section pointer. This is
786 // not type-safe but we only use Arm_input_section not the base class.
787 static Arm_input_section<big_endian>*
788 as_arm_input_section(Output_relaxed_input_section* poris)
789 { return static_cast<Arm_input_section<big_endian>*>(poris); }
792 // Write data to output file.
794 do_write(Output_file*);
796 // Return required alignment of this.
800 if (this->is_stub_table_owner())
801 return std::max(this->stub_table_->addralign(),
802 this->original_addralign_);
804 return this->original_addralign_;
807 // Finalize data size.
809 set_final_data_size();
811 // Reset address and file offset.
813 do_reset_address_and_file_offset();
817 do_output_offset(const Relobj* object, unsigned int shndx,
818 section_offset_type offset,
819 section_offset_type* poutput) const
821 if ((object == this->relobj())
822 && (shndx == this->shndx())
824 && (convert_types<uint64_t, section_offset_type>(offset)
825 <= this->original_size_))
835 // Copying is not allowed.
836 Arm_input_section(const Arm_input_section&);
837 Arm_input_section& operator=(const Arm_input_section&);
839 // Address alignment of the original input section.
840 uint64_t original_addralign_;
841 // Section size of the original input section.
842 uint64_t original_size_;
844 Stub_table<big_endian>* stub_table_;
847 // Arm output section class. This is defined mainly to add a number of
848 // stub generation methods.
850 template<bool big_endian>
851 class Arm_output_section : public Output_section
854 Arm_output_section(const char* name, elfcpp::Elf_Word type,
855 elfcpp::Elf_Xword flags)
856 : Output_section(name, type, flags)
859 ~Arm_output_section()
862 // Group input sections for stub generation.
864 group_sections(section_size_type, bool, Target_arm<big_endian>*);
866 // Downcast a base pointer to an Arm_output_section pointer. This is
867 // not type-safe but we only use Arm_output_section not the base class.
868 static Arm_output_section<big_endian>*
869 as_arm_output_section(Output_section* os)
870 { return static_cast<Arm_output_section<big_endian>*>(os); }
874 typedef Output_section::Input_section Input_section;
875 typedef Output_section::Input_section_list Input_section_list;
877 // Create a stub group.
878 void create_stub_group(Input_section_list::const_iterator,
879 Input_section_list::const_iterator,
880 Input_section_list::const_iterator,
881 Target_arm<big_endian>*,
882 std::vector<Output_relaxed_input_section*>*);
887 template<bool big_endian>
888 class Arm_relobj : public Sized_relobj<32, big_endian>
891 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
893 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
894 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
895 : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
896 stub_tables_(), local_symbol_is_thumb_function_(),
897 attributes_section_data_(NULL)
901 { delete this->attributes_section_data_; }
903 // Return the stub table of the SHNDX-th section if there is one.
904 Stub_table<big_endian>*
905 stub_table(unsigned int shndx) const
907 gold_assert(shndx < this->stub_tables_.size());
908 return this->stub_tables_[shndx];
911 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
913 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
915 gold_assert(shndx < this->stub_tables_.size());
916 this->stub_tables_[shndx] = stub_table;
919 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
920 // index. This is only valid after do_count_local_symbol is called.
922 local_symbol_is_thumb_function(unsigned int r_sym) const
924 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
925 return this->local_symbol_is_thumb_function_[r_sym];
928 // Scan all relocation sections for stub generation.
930 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
933 // Convert regular input section with index SHNDX to a relaxed section.
935 convert_input_section_to_relaxed_section(unsigned shndx)
937 // The stubs have relocations and we need to process them after writing
938 // out the stubs. So relocation now must follow section write.
939 this->invalidate_section_offset(shndx);
940 this->set_relocs_must_follow_section_writes();
943 // Downcast a base pointer to an Arm_relobj pointer. This is
944 // not type-safe but we only use Arm_relobj not the base class.
945 static Arm_relobj<big_endian>*
946 as_arm_relobj(Relobj* relobj)
947 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
949 // Processor-specific flags in ELF file header. This is valid only after
952 processor_specific_flags() const
953 { return this->processor_specific_flags_; }
955 // Attribute section data This is the contents of the .ARM.attribute section
957 const Attributes_section_data*
958 attributes_section_data() const
959 { return this->attributes_section_data_; }
962 // Post constructor setup.
966 // Call parent's setup method.
967 Sized_relobj<32, big_endian>::do_setup();
969 // Initialize look-up tables.
970 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
971 this->stub_tables_.swap(empty_stub_table_list);
974 // Count the local symbols.
976 do_count_local_symbols(Stringpool_template<char>*,
977 Stringpool_template<char>*);
980 do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
981 const unsigned char* pshdrs,
982 typename Sized_relobj<32, big_endian>::Views* pivews);
984 // Read the symbol information.
986 do_read_symbols(Read_symbols_data* sd);
989 // List of stub tables.
990 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
991 Stub_table_list stub_tables_;
992 // Bit vector to tell if a local symbol is a thumb function or not.
993 // This is only valid after do_count_local_symbol is called.
994 std::vector<bool> local_symbol_is_thumb_function_;
995 // processor-specific flags in ELF file header.
996 elfcpp::Elf_Word processor_specific_flags_;
997 // Object attributes if there is an .ARM.attributes section or NULL.
998 Attributes_section_data* attributes_section_data_;
1001 // Arm_dynobj class.
1003 template<bool big_endian>
1004 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1007 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1008 const elfcpp::Ehdr<32, big_endian>& ehdr)
1009 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1010 processor_specific_flags_(0), attributes_section_data_(NULL)
1014 { delete this->attributes_section_data_; }
1016 // Downcast a base pointer to an Arm_relobj pointer. This is
1017 // not type-safe but we only use Arm_relobj not the base class.
1018 static Arm_dynobj<big_endian>*
1019 as_arm_dynobj(Dynobj* dynobj)
1020 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1022 // Processor-specific flags in ELF file header. This is valid only after
1025 processor_specific_flags() const
1026 { return this->processor_specific_flags_; }
1028 // Attributes section data.
1029 const Attributes_section_data*
1030 attributes_section_data() const
1031 { return this->attributes_section_data_; }
1034 // Read the symbol information.
1036 do_read_symbols(Read_symbols_data* sd);
1039 // processor-specific flags in ELF file header.
1040 elfcpp::Elf_Word processor_specific_flags_;
1041 // Object attributes if there is an .ARM.attributes section or NULL.
1042 Attributes_section_data* attributes_section_data_;
1045 // Functor to read reloc addends during stub generation.
1047 template<int sh_type, bool big_endian>
1048 struct Stub_addend_reader
1050 // Return the addend for a relocation of a particular type. Depending
1051 // on whether this is a REL or RELA relocation, read the addend from a
1052 // view or from a Reloc object.
1053 elfcpp::Elf_types<32>::Elf_Swxword
1055 unsigned int /* r_type */,
1056 const unsigned char* /* view */,
1057 const typename Reloc_types<sh_type,
1058 32, big_endian>::Reloc& /* reloc */) const;
1061 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1063 template<bool big_endian>
1064 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1066 elfcpp::Elf_types<32>::Elf_Swxword
1069 const unsigned char*,
1070 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1073 // Specialized Stub_addend_reader for RELA type relocation sections.
1074 // We currently do not handle RELA type relocation sections but it is trivial
1075 // to implement the addend reader. This is provided for completeness and to
1076 // make it easier to add support for RELA relocation sections in the future.
1078 template<bool big_endian>
1079 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1081 elfcpp::Elf_types<32>::Elf_Swxword
1084 const unsigned char*,
1085 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1086 big_endian>::Reloc& reloc) const
1087 { return reloc.get_r_addend(); }
1090 // Utilities for manipulating integers of up to 32-bits
1094 // Sign extend an n-bit unsigned integer stored in an uint32_t into
1095 // an int32_t. NO_BITS must be between 1 to 32.
1096 template<int no_bits>
1097 static inline int32_t
1098 sign_extend(uint32_t bits)
1100 gold_assert(no_bits >= 0 && no_bits <= 32);
1102 return static_cast<int32_t>(bits);
1103 uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
1105 uint32_t top_bit = 1U << (no_bits - 1);
1106 int32_t as_signed = static_cast<int32_t>(bits);
1107 return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
1110 // Detects overflow of an NO_BITS integer stored in a uint32_t.
1111 template<int no_bits>
1113 has_overflow(uint32_t bits)
1115 gold_assert(no_bits >= 0 && no_bits <= 32);
1118 int32_t max = (1 << (no_bits - 1)) - 1;
1119 int32_t min = -(1 << (no_bits - 1));
1120 int32_t as_signed = static_cast<int32_t>(bits);
1121 return as_signed > max || as_signed < min;
1124 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
1125 // fits in the given number of bits as either a signed or unsigned value.
1126 // For example, has_signed_unsigned_overflow<8> would check
1127 // -128 <= bits <= 255
1128 template<int no_bits>
1130 has_signed_unsigned_overflow(uint32_t bits)
1132 gold_assert(no_bits >= 2 && no_bits <= 32);
1135 int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
1136 int32_t min = -(1 << (no_bits - 1));
1137 int32_t as_signed = static_cast<int32_t>(bits);
1138 return as_signed > max || as_signed < min;
1141 // Select bits from A and B using bits in MASK. For each n in [0..31],
1142 // the n-th bit in the result is chosen from the n-th bits of A and B.
1143 // A zero selects A and a one selects B.
1144 static inline uint32_t
1145 bit_select(uint32_t a, uint32_t b, uint32_t mask)
1146 { return (a & ~mask) | (b & mask); }
1149 template<bool big_endian>
1150 class Target_arm : public Sized_target<32, big_endian>
1153 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
1156 // When were are relocating a stub, we pass this as the relocation number.
1157 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
1160 : Sized_target<32, big_endian>(&arm_info),
1161 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
1162 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL), stub_tables_(),
1163 stub_factory_(Stub_factory::get_instance()), may_use_blx_(false),
1164 should_force_pic_veneer_(false), arm_input_section_map_(),
1165 attributes_section_data_(NULL)
1168 // Whether we can use BLX.
1171 { return this->may_use_blx_; }
1173 // Set use-BLX flag.
1175 set_may_use_blx(bool value)
1176 { this->may_use_blx_ = value; }
1178 // Whether we force PCI branch veneers.
1180 should_force_pic_veneer() const
1181 { return this->should_force_pic_veneer_; }
1183 // Set PIC veneer flag.
1185 set_should_force_pic_veneer(bool value)
1186 { this->should_force_pic_veneer_ = value; }
1188 // Whether we use THUMB-2 instructions.
1190 using_thumb2() const
1192 Object_attribute* attr =
1193 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
1194 int arch = attr->int_value();
1195 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
1198 // Whether we use THUMB/THUMB-2 instructions only.
1200 using_thumb_only() const
1202 Object_attribute* attr =
1203 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
1204 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
1205 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
1207 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
1208 return attr->int_value() == 'M';
1211 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
1213 may_use_arm_nop() const
1215 Object_attribute* attr =
1216 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
1217 int arch = attr->int_value();
1218 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
1219 || arch == elfcpp::TAG_CPU_ARCH_V6K
1220 || arch == elfcpp::TAG_CPU_ARCH_V7
1221 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
1224 // Whether we have THUMB-2 NOP.W instruction.
1226 may_use_thumb2_nop() const
1228 Object_attribute* attr =
1229 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
1230 int arch = attr->int_value();
1231 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
1232 || arch == elfcpp::TAG_CPU_ARCH_V7
1233 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
1236 // Process the relocations to determine unreferenced sections for
1237 // garbage collection.
1239 gc_process_relocs(Symbol_table* symtab,
1241 Sized_relobj<32, big_endian>* object,
1242 unsigned int data_shndx,
1243 unsigned int sh_type,
1244 const unsigned char* prelocs,
1246 Output_section* output_section,
1247 bool needs_special_offset_handling,
1248 size_t local_symbol_count,
1249 const unsigned char* plocal_symbols);
1251 // Scan the relocations to look for symbol adjustments.
1253 scan_relocs(Symbol_table* symtab,
1255 Sized_relobj<32, big_endian>* object,
1256 unsigned int data_shndx,
1257 unsigned int sh_type,
1258 const unsigned char* prelocs,
1260 Output_section* output_section,
1261 bool needs_special_offset_handling,
1262 size_t local_symbol_count,
1263 const unsigned char* plocal_symbols);
1265 // Finalize the sections.
1267 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
1269 // Return the value to use for a dynamic symbol which requires special
1272 do_dynsym_value(const Symbol*) const;
1274 // Relocate a section.
1276 relocate_section(const Relocate_info<32, big_endian>*,
1277 unsigned int sh_type,
1278 const unsigned char* prelocs,
1280 Output_section* output_section,
1281 bool needs_special_offset_handling,
1282 unsigned char* view,
1283 Arm_address view_address,
1284 section_size_type view_size,
1285 const Reloc_symbol_changes*);
1287 // Scan the relocs during a relocatable link.
1289 scan_relocatable_relocs(Symbol_table* symtab,
1291 Sized_relobj<32, big_endian>* object,
1292 unsigned int data_shndx,
1293 unsigned int sh_type,
1294 const unsigned char* prelocs,
1296 Output_section* output_section,
1297 bool needs_special_offset_handling,
1298 size_t local_symbol_count,
1299 const unsigned char* plocal_symbols,
1300 Relocatable_relocs*);
1302 // Relocate a section during a relocatable link.
1304 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
1305 unsigned int sh_type,
1306 const unsigned char* prelocs,
1308 Output_section* output_section,
1309 off_t offset_in_output_section,
1310 const Relocatable_relocs*,
1311 unsigned char* view,
1312 Arm_address view_address,
1313 section_size_type view_size,
1314 unsigned char* reloc_view,
1315 section_size_type reloc_view_size);
1317 // Return whether SYM is defined by the ABI.
1319 do_is_defined_by_abi(Symbol* sym) const
1320 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
1322 // Return the size of the GOT section.
1326 gold_assert(this->got_ != NULL);
1327 return this->got_->data_size();
1330 // Map platform-specific reloc types
1332 get_real_reloc_type (unsigned int r_type);
1335 // Methods to support stub-generations.
1338 // Return the stub factory
1340 stub_factory() const
1341 { return this->stub_factory_; }
1343 // Make a new Arm_input_section object.
1344 Arm_input_section<big_endian>*
1345 new_arm_input_section(Relobj*, unsigned int);
1347 // Find the Arm_input_section object corresponding to the SHNDX-th input
1348 // section of RELOBJ.
1349 Arm_input_section<big_endian>*
1350 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
1352 // Make a new Stub_table
1353 Stub_table<big_endian>*
1354 new_stub_table(Arm_input_section<big_endian>*);
1356 // Scan a section for stub generation.
1358 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
1359 const unsigned char*, size_t, Output_section*,
1360 bool, const unsigned char*, Arm_address,
1365 relocate_stub(Reloc_stub*, const Relocate_info<32, big_endian>*,
1366 Output_section*, unsigned char*, Arm_address,
1369 // Get the default ARM target.
1370 static Target_arm<big_endian>*
1373 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
1374 && parameters->target().is_big_endian() == big_endian);
1375 return static_cast<Target_arm<big_endian>*>(
1376 parameters->sized_target<32, big_endian>());
1379 // Whether relocation type uses LSB to distinguish THUMB addresses.
1381 reloc_uses_thumb_bit(unsigned int r_type);
1384 // Make an ELF object.
1386 do_make_elf_object(const std::string&, Input_file*, off_t,
1387 const elfcpp::Ehdr<32, big_endian>& ehdr);
1390 do_make_elf_object(const std::string&, Input_file*, off_t,
1391 const elfcpp::Ehdr<32, !big_endian>&)
1392 { gold_unreachable(); }
1395 do_make_elf_object(const std::string&, Input_file*, off_t,
1396 const elfcpp::Ehdr<64, false>&)
1397 { gold_unreachable(); }
1400 do_make_elf_object(const std::string&, Input_file*, off_t,
1401 const elfcpp::Ehdr<64, true>&)
1402 { gold_unreachable(); }
1404 // Make an output section.
1406 do_make_output_section(const char* name, elfcpp::Elf_Word type,
1407 elfcpp::Elf_Xword flags)
1408 { return new Arm_output_section<big_endian>(name, type, flags); }
1411 do_adjust_elf_header(unsigned char* view, int len) const;
1413 // We only need to generate stubs, and hence perform relaxation if we are
1414 // not doing relocatable linking.
1416 do_may_relax() const
1417 { return !parameters->options().relocatable(); }
1420 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
1422 // Determine whether an object attribute tag takes an integer, a
1425 do_attribute_arg_type(int tag) const;
1427 // Reorder tags during output.
1429 do_attributes_order(int num) const;
1432 // The class which scans relocations.
1437 : issued_non_pic_error_(false)
1441 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
1442 Sized_relobj<32, big_endian>* object,
1443 unsigned int data_shndx,
1444 Output_section* output_section,
1445 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
1446 const elfcpp::Sym<32, big_endian>& lsym);
1449 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
1450 Sized_relobj<32, big_endian>* object,
1451 unsigned int data_shndx,
1452 Output_section* output_section,
1453 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
1458 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
1459 unsigned int r_type);
1462 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
1463 unsigned int r_type, Symbol*);
1466 check_non_pic(Relobj*, unsigned int r_type);
1468 // Almost identical to Symbol::needs_plt_entry except that it also
1469 // handles STT_ARM_TFUNC.
1471 symbol_needs_plt_entry(const Symbol* sym)
1473 // An undefined symbol from an executable does not need a PLT entry.
1474 if (sym->is_undefined() && !parameters->options().shared())
1477 return (!parameters->doing_static_link()
1478 && (sym->type() == elfcpp::STT_FUNC
1479 || sym->type() == elfcpp::STT_ARM_TFUNC)
1480 && (sym->is_from_dynobj()
1481 || sym->is_undefined()
1482 || sym->is_preemptible()));
1485 // Whether we have issued an error about a non-PIC compilation.
1486 bool issued_non_pic_error_;
1489 // The class which implements relocation.
1499 // Return whether the static relocation needs to be applied.
1501 should_apply_static_reloc(const Sized_symbol<32>* gsym,
1504 Output_section* output_section);
1506 // Do a relocation. Return false if the caller should not issue
1507 // any warnings about this relocation.
1509 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
1510 Output_section*, size_t relnum,
1511 const elfcpp::Rel<32, big_endian>&,
1512 unsigned int r_type, const Sized_symbol<32>*,
1513 const Symbol_value<32>*,
1514 unsigned char*, Arm_address,
1517 // Return whether we want to pass flag NON_PIC_REF for this
1518 // reloc. This means the relocation type accesses a symbol not via
1521 reloc_is_non_pic (unsigned int r_type)
1525 // These relocation types reference GOT or PLT entries explicitly.
1526 case elfcpp::R_ARM_GOT_BREL:
1527 case elfcpp::R_ARM_GOT_ABS:
1528 case elfcpp::R_ARM_GOT_PREL:
1529 case elfcpp::R_ARM_GOT_BREL12:
1530 case elfcpp::R_ARM_PLT32_ABS:
1531 case elfcpp::R_ARM_TLS_GD32:
1532 case elfcpp::R_ARM_TLS_LDM32:
1533 case elfcpp::R_ARM_TLS_IE32:
1534 case elfcpp::R_ARM_TLS_IE12GP:
1536 // These relocate types may use PLT entries.
1537 case elfcpp::R_ARM_CALL:
1538 case elfcpp::R_ARM_THM_CALL:
1539 case elfcpp::R_ARM_JUMP24:
1540 case elfcpp::R_ARM_THM_JUMP24:
1541 case elfcpp::R_ARM_THM_JUMP19:
1542 case elfcpp::R_ARM_PLT32:
1543 case elfcpp::R_ARM_THM_XPC22:
1552 // A class which returns the size required for a relocation type,
1553 // used while scanning relocs during a relocatable link.
1554 class Relocatable_size_for_reloc
1558 get_size_for_reloc(unsigned int, Relobj*);
1561 // Get the GOT section, creating it if necessary.
1562 Output_data_got<32, big_endian>*
1563 got_section(Symbol_table*, Layout*);
1565 // Get the GOT PLT section.
1567 got_plt_section() const
1569 gold_assert(this->got_plt_ != NULL);
1570 return this->got_plt_;
1573 // Create a PLT entry for a global symbol.
1575 make_plt_entry(Symbol_table*, Layout*, Symbol*);
1577 // Get the PLT section.
1578 const Output_data_plt_arm<big_endian>*
1581 gold_assert(this->plt_ != NULL);
1585 // Get the dynamic reloc section, creating it if necessary.
1587 rel_dyn_section(Layout*);
1589 // Return true if the symbol may need a COPY relocation.
1590 // References from an executable object to non-function symbols
1591 // defined in a dynamic object may need a COPY relocation.
1593 may_need_copy_reloc(Symbol* gsym)
1595 return (gsym->type() != elfcpp::STT_ARM_TFUNC
1596 && gsym->may_need_copy_reloc());
1599 // Add a potential copy relocation.
1601 copy_reloc(Symbol_table* symtab, Layout* layout,
1602 Sized_relobj<32, big_endian>* object,
1603 unsigned int shndx, Output_section* output_section,
1604 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
1606 this->copy_relocs_.copy_reloc(symtab, layout,
1607 symtab->get_sized_symbol<32>(sym),
1608 object, shndx, output_section, reloc,
1609 this->rel_dyn_section(layout));
1612 // Whether two EABI versions are compatible.
1614 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
1616 // Merge processor-specific flags from input object and those in the ELF
1617 // header of the output.
1619 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
1621 // Get the secondary compatible architecture.
1623 get_secondary_compatible_arch(const Attributes_section_data*);
1625 // Set the secondary compatible architecture.
1627 set_secondary_compatible_arch(Attributes_section_data*, int);
1630 tag_cpu_arch_combine(const char*, int, int*, int, int);
1632 // Helper to print AEABI enum tag value.
1634 aeabi_enum_name(unsigned int);
1636 // Return string value for TAG_CPU_name.
1638 tag_cpu_name_value(unsigned int);
1640 // Merge object attributes from input object and those in the output.
1642 merge_object_attributes(const char*, const Attributes_section_data*);
1644 // Helper to get an AEABI object attribute
1646 get_aeabi_object_attribute(int tag) const
1648 Attributes_section_data* pasd = this->attributes_section_data_;
1649 gold_assert(pasd != NULL);
1650 Object_attribute* attr =
1651 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
1652 gold_assert(attr != NULL);
1657 // Methods to support stub-generations.
1660 // Group input sections for stub generation.
1662 group_sections(Layout*, section_size_type, bool);
1664 // Scan a relocation for stub generation.
1666 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
1667 const Sized_symbol<32>*, unsigned int,
1668 const Symbol_value<32>*,
1669 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
1671 // Scan a relocation section for stub.
1672 template<int sh_type>
1674 scan_reloc_section_for_stubs(
1675 const Relocate_info<32, big_endian>* relinfo,
1676 const unsigned char* prelocs,
1678 Output_section* output_section,
1679 bool needs_special_offset_handling,
1680 const unsigned char* view,
1681 elfcpp::Elf_types<32>::Elf_Addr view_address,
1684 // Information about this specific target which we pass to the
1685 // general Target structure.
1686 static const Target::Target_info arm_info;
1688 // The types of GOT entries needed for this platform.
1691 GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol
1694 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
1696 // Map input section to Arm_input_section.
1697 typedef Unordered_map<Input_section_specifier,
1698 Arm_input_section<big_endian>*,
1699 Input_section_specifier::hash,
1700 Input_section_specifier::equal_to>
1701 Arm_input_section_map;
1704 Output_data_got<32, big_endian>* got_;
1706 Output_data_plt_arm<big_endian>* plt_;
1707 // The GOT PLT section.
1708 Output_data_space* got_plt_;
1709 // The dynamic reloc section.
1710 Reloc_section* rel_dyn_;
1711 // Relocs saved to avoid a COPY reloc.
1712 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
1713 // Space for variables copied with a COPY reloc.
1714 Output_data_space* dynbss_;
1715 // Vector of Stub_tables created.
1716 Stub_table_list stub_tables_;
1718 const Stub_factory &stub_factory_;
1719 // Whether we can use BLX.
1721 // Whether we force PIC branch veneers.
1722 bool should_force_pic_veneer_;
1723 // Map for locating Arm_input_sections.
1724 Arm_input_section_map arm_input_section_map_;
1725 // Attributes section data in output.
1726 Attributes_section_data* attributes_section_data_;
1729 template<bool big_endian>
1730 const Target::Target_info Target_arm<big_endian>::arm_info =
1733 big_endian, // is_big_endian
1734 elfcpp::EM_ARM, // machine_code
1735 false, // has_make_symbol
1736 false, // has_resolve
1737 false, // has_code_fill
1738 true, // is_default_stack_executable
1740 "/usr/lib/libc.so.1", // dynamic_linker
1741 0x8000, // default_text_segment_address
1742 0x1000, // abi_pagesize (overridable by -z max-page-size)
1743 0x1000, // common_pagesize (overridable by -z common-page-size)
1744 elfcpp::SHN_UNDEF, // small_common_shndx
1745 elfcpp::SHN_UNDEF, // large_common_shndx
1746 0, // small_common_section_flags
1747 0, // large_common_section_flags
1748 ".ARM.attributes", // attributes_section
1749 "aeabi" // attributes_vendor
1752 // Arm relocate functions class
1755 template<bool big_endian>
1756 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
1761 STATUS_OKAY, // No error during relocation.
1762 STATUS_OVERFLOW, // Relocation oveflow.
1763 STATUS_BAD_RELOC // Relocation cannot be applied.
1767 typedef Relocate_functions<32, big_endian> Base;
1768 typedef Arm_relocate_functions<big_endian> This;
1770 // Encoding of imm16 argument for movt and movw ARM instructions
1773 // imm16 := imm4 | imm12
1775 // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
1776 // +-------+---------------+-------+-------+-----------------------+
1777 // | | |imm4 | |imm12 |
1778 // +-------+---------------+-------+-------+-----------------------+
1780 // Extract the relocation addend from VAL based on the ARM
1781 // instruction encoding described above.
1782 static inline typename elfcpp::Swap<32, big_endian>::Valtype
1783 extract_arm_movw_movt_addend(
1784 typename elfcpp::Swap<32, big_endian>::Valtype val)
1786 // According to the Elf ABI for ARM Architecture the immediate
1787 // field is sign-extended to form the addend.
1788 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
1791 // Insert X into VAL based on the ARM instruction encoding described
1793 static inline typename elfcpp::Swap<32, big_endian>::Valtype
1794 insert_val_arm_movw_movt(
1795 typename elfcpp::Swap<32, big_endian>::Valtype val,
1796 typename elfcpp::Swap<32, big_endian>::Valtype x)
1800 val |= (x & 0xf000) << 4;
1804 // Encoding of imm16 argument for movt and movw Thumb2 instructions
1807 // imm16 := imm4 | i | imm3 | imm8
1809 // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
1810 // +---------+-+-----------+-------++-+-----+-------+---------------+
1811 // | |i| |imm4 || |imm3 | |imm8 |
1812 // +---------+-+-----------+-------++-+-----+-------+---------------+
1814 // Extract the relocation addend from VAL based on the Thumb2
1815 // instruction encoding described above.
1816 static inline typename elfcpp::Swap<32, big_endian>::Valtype
1817 extract_thumb_movw_movt_addend(
1818 typename elfcpp::Swap<32, big_endian>::Valtype val)
1820 // According to the Elf ABI for ARM Architecture the immediate
1821 // field is sign-extended to form the addend.
1822 return utils::sign_extend<16>(((val >> 4) & 0xf000)
1823 | ((val >> 15) & 0x0800)
1824 | ((val >> 4) & 0x0700)
1828 // Insert X into VAL based on the Thumb2 instruction encoding
1830 static inline typename elfcpp::Swap<32, big_endian>::Valtype
1831 insert_val_thumb_movw_movt(
1832 typename elfcpp::Swap<32, big_endian>::Valtype val,
1833 typename elfcpp::Swap<32, big_endian>::Valtype x)
1836 val |= (x & 0xf000) << 4;
1837 val |= (x & 0x0800) << 15;
1838 val |= (x & 0x0700) << 4;
1839 val |= (x & 0x00ff);
1843 // Handle ARM long branches.
1844 static typename This::Status
1845 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
1846 unsigned char *, const Sized_symbol<32>*,
1847 const Arm_relobj<big_endian>*, unsigned int,
1848 const Symbol_value<32>*, Arm_address, Arm_address, bool);
1850 // Handle THUMB long branches.
1851 static typename This::Status
1852 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
1853 unsigned char *, const Sized_symbol<32>*,
1854 const Arm_relobj<big_endian>*, unsigned int,
1855 const Symbol_value<32>*, Arm_address, Arm_address, bool);
1859 // R_ARM_ABS8: S + A
1860 static inline typename This::Status
1861 abs8(unsigned char *view,
1862 const Sized_relobj<32, big_endian>* object,
1863 const Symbol_value<32>* psymval)
1865 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
1866 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
1867 Valtype* wv = reinterpret_cast<Valtype*>(view);
1868 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
1869 Reltype addend = utils::sign_extend<8>(val);
1870 Reltype x = psymval->value(object, addend);
1871 val = utils::bit_select(val, x, 0xffU);
1872 elfcpp::Swap<8, big_endian>::writeval(wv, val);
1873 return (utils::has_signed_unsigned_overflow<8>(x)
1874 ? This::STATUS_OVERFLOW
1875 : This::STATUS_OKAY);
1878 // R_ARM_THM_ABS5: S + A
1879 static inline typename This::Status
1880 thm_abs5(unsigned char *view,
1881 const Sized_relobj<32, big_endian>* object,
1882 const Symbol_value<32>* psymval)
1884 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
1885 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
1886 Valtype* wv = reinterpret_cast<Valtype*>(view);
1887 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
1888 Reltype addend = (val & 0x7e0U) >> 6;
1889 Reltype x = psymval->value(object, addend);
1890 val = utils::bit_select(val, x << 6, 0x7e0U);
1891 elfcpp::Swap<16, big_endian>::writeval(wv, val);
1892 return (utils::has_overflow<5>(x)
1893 ? This::STATUS_OVERFLOW
1894 : This::STATUS_OKAY);
1897 // R_ARM_ABS12: S + A
1898 static inline typename This::Status
1899 abs12(unsigned char *view,
1900 const Sized_relobj<32, big_endian>* object,
1901 const Symbol_value<32>* psymval)
1903 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
1904 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
1905 Valtype* wv = reinterpret_cast<Valtype*>(view);
1906 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
1907 Reltype addend = val & 0x0fffU;
1908 Reltype x = psymval->value(object, addend);
1909 val = utils::bit_select(val, x, 0x0fffU);
1910 elfcpp::Swap<32, big_endian>::writeval(wv, val);
1911 return (utils::has_overflow<12>(x)
1912 ? This::STATUS_OVERFLOW
1913 : This::STATUS_OKAY);
1916 // R_ARM_ABS16: S + A
1917 static inline typename This::Status
1918 abs16(unsigned char *view,
1919 const Sized_relobj<32, big_endian>* object,
1920 const Symbol_value<32>* psymval)
1922 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
1923 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
1924 Valtype* wv = reinterpret_cast<Valtype*>(view);
1925 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
1926 Reltype addend = utils::sign_extend<16>(val);
1927 Reltype x = psymval->value(object, addend);
1928 val = utils::bit_select(val, x, 0xffffU);
1929 elfcpp::Swap<16, big_endian>::writeval(wv, val);
1930 return (utils::has_signed_unsigned_overflow<16>(x)
1931 ? This::STATUS_OVERFLOW
1932 : This::STATUS_OKAY);
1935 // R_ARM_ABS32: (S + A) | T
1936 static inline typename This::Status
1937 abs32(unsigned char *view,
1938 const Sized_relobj<32, big_endian>* object,
1939 const Symbol_value<32>* psymval,
1940 Arm_address thumb_bit)
1942 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
1943 Valtype* wv = reinterpret_cast<Valtype*>(view);
1944 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
1945 Valtype x = psymval->value(object, addend) | thumb_bit;
1946 elfcpp::Swap<32, big_endian>::writeval(wv, x);
1947 return This::STATUS_OKAY;
1950 // R_ARM_REL32: (S + A) | T - P
1951 static inline typename This::Status
1952 rel32(unsigned char *view,
1953 const Sized_relobj<32, big_endian>* object,
1954 const Symbol_value<32>* psymval,
1955 Arm_address address,
1956 Arm_address thumb_bit)
1958 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
1959 Valtype* wv = reinterpret_cast<Valtype*>(view);
1960 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
1961 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
1962 elfcpp::Swap<32, big_endian>::writeval(wv, x);
1963 return This::STATUS_OKAY;
1966 // R_ARM_THM_CALL: (S + A) | T - P
1967 static inline typename This::Status
1968 thm_call(const Relocate_info<32, big_endian>* relinfo, unsigned char *view,
1969 const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object,
1970 unsigned int r_sym, const Symbol_value<32>* psymval,
1971 Arm_address address, Arm_address thumb_bit,
1972 bool is_weakly_undefined_without_plt)
1974 return thumb_branch_common(elfcpp::R_ARM_THM_CALL, relinfo, view, gsym,
1975 object, r_sym, psymval, address, thumb_bit,
1976 is_weakly_undefined_without_plt);
1979 // R_ARM_THM_JUMP24: (S + A) | T - P
1980 static inline typename This::Status
1981 thm_jump24(const Relocate_info<32, big_endian>* relinfo, unsigned char *view,
1982 const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object,
1983 unsigned int r_sym, const Symbol_value<32>* psymval,
1984 Arm_address address, Arm_address thumb_bit,
1985 bool is_weakly_undefined_without_plt)
1987 return thumb_branch_common(elfcpp::R_ARM_THM_JUMP24, relinfo, view, gsym,
1988 object, r_sym, psymval, address, thumb_bit,
1989 is_weakly_undefined_without_plt);
1992 // R_ARM_THM_XPC22: (S + A) | T - P
1993 static inline typename This::Status
1994 thm_xpc22(const Relocate_info<32, big_endian>* relinfo, unsigned char *view,
1995 const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object,
1996 unsigned int r_sym, const Symbol_value<32>* psymval,
1997 Arm_address address, Arm_address thumb_bit,
1998 bool is_weakly_undefined_without_plt)
2000 return thumb_branch_common(elfcpp::R_ARM_THM_XPC22, relinfo, view, gsym,
2001 object, r_sym, psymval, address, thumb_bit,
2002 is_weakly_undefined_without_plt);
2005 // R_ARM_BASE_PREL: B(S) + A - P
2006 static inline typename This::Status
2007 base_prel(unsigned char* view,
2009 Arm_address address)
2011 Base::rel32(view, origin - address);
2015 // R_ARM_BASE_ABS: B(S) + A
2016 static inline typename This::Status
2017 base_abs(unsigned char* view,
2020 Base::rel32(view, origin);
2024 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
2025 static inline typename This::Status
2026 got_brel(unsigned char* view,
2027 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
2029 Base::rel32(view, got_offset);
2030 return This::STATUS_OKAY;
2033 // R_ARM_GOT_PREL: GOT(S) + A - P
2034 static inline typename This::Status
2035 got_prel(unsigned char *view,
2036 Arm_address got_entry,
2037 Arm_address address)
2039 Base::rel32(view, got_entry - address);
2040 return This::STATUS_OKAY;
2043 // R_ARM_PLT32: (S + A) | T - P
2044 static inline typename This::Status
2045 plt32(const Relocate_info<32, big_endian>* relinfo,
2046 unsigned char *view,
2047 const Sized_symbol<32>* gsym,
2048 const Arm_relobj<big_endian>* object,
2050 const Symbol_value<32>* psymval,
2051 Arm_address address,
2052 Arm_address thumb_bit,
2053 bool is_weakly_undefined_without_plt)
2055 return arm_branch_common(elfcpp::R_ARM_PLT32, relinfo, view, gsym,
2056 object, r_sym, psymval, address, thumb_bit,
2057 is_weakly_undefined_without_plt);
2060 // R_ARM_XPC25: (S + A) | T - P
2061 static inline typename This::Status
2062 xpc25(const Relocate_info<32, big_endian>* relinfo,
2063 unsigned char *view,
2064 const Sized_symbol<32>* gsym,
2065 const Arm_relobj<big_endian>* object,
2067 const Symbol_value<32>* psymval,
2068 Arm_address address,
2069 Arm_address thumb_bit,
2070 bool is_weakly_undefined_without_plt)
2072 return arm_branch_common(elfcpp::R_ARM_XPC25, relinfo, view, gsym,
2073 object, r_sym, psymval, address, thumb_bit,
2074 is_weakly_undefined_without_plt);
2077 // R_ARM_CALL: (S + A) | T - P
2078 static inline typename This::Status
2079 call(const Relocate_info<32, big_endian>* relinfo,
2080 unsigned char *view,
2081 const Sized_symbol<32>* gsym,
2082 const Arm_relobj<big_endian>* object,
2084 const Symbol_value<32>* psymval,
2085 Arm_address address,
2086 Arm_address thumb_bit,
2087 bool is_weakly_undefined_without_plt)
2089 return arm_branch_common(elfcpp::R_ARM_CALL, relinfo, view, gsym,
2090 object, r_sym, psymval, address, thumb_bit,
2091 is_weakly_undefined_without_plt);
2094 // R_ARM_JUMP24: (S + A) | T - P
2095 static inline typename This::Status
2096 jump24(const Relocate_info<32, big_endian>* relinfo,
2097 unsigned char *view,
2098 const Sized_symbol<32>* gsym,
2099 const Arm_relobj<big_endian>* object,
2101 const Symbol_value<32>* psymval,
2102 Arm_address address,
2103 Arm_address thumb_bit,
2104 bool is_weakly_undefined_without_plt)
2106 return arm_branch_common(elfcpp::R_ARM_JUMP24, relinfo, view, gsym,
2107 object, r_sym, psymval, address, thumb_bit,
2108 is_weakly_undefined_without_plt);
2111 // R_ARM_PREL: (S + A) | T - P
2112 static inline typename This::Status
2113 prel31(unsigned char *view,
2114 const Sized_relobj<32, big_endian>* object,
2115 const Symbol_value<32>* psymval,
2116 Arm_address address,
2117 Arm_address thumb_bit)
2119 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2120 Valtype* wv = reinterpret_cast<Valtype*>(view);
2121 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2122 Valtype addend = utils::sign_extend<31>(val);
2123 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
2124 val = utils::bit_select(val, x, 0x7fffffffU);
2125 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2126 return (utils::has_overflow<31>(x) ?
2127 This::STATUS_OVERFLOW : This::STATUS_OKAY);
2130 // R_ARM_MOVW_ABS_NC: (S + A) | T
2131 static inline typename This::Status
2132 movw_abs_nc(unsigned char *view,
2133 const Sized_relobj<32, big_endian>* object,
2134 const Symbol_value<32>* psymval,
2135 Arm_address thumb_bit)
2137 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2138 Valtype* wv = reinterpret_cast<Valtype*>(view);
2139 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2140 Valtype addend = This::extract_arm_movw_movt_addend(val);
2141 Valtype x = psymval->value(object, addend) | thumb_bit;
2142 val = This::insert_val_arm_movw_movt(val, x);
2143 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2144 return This::STATUS_OKAY;
2147 // R_ARM_MOVT_ABS: S + A
2148 static inline typename This::Status
2149 movt_abs(unsigned char *view,
2150 const Sized_relobj<32, big_endian>* object,
2151 const Symbol_value<32>* psymval)
2153 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2154 Valtype* wv = reinterpret_cast<Valtype*>(view);
2155 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2156 Valtype addend = This::extract_arm_movw_movt_addend(val);
2157 Valtype x = psymval->value(object, addend) >> 16;
2158 val = This::insert_val_arm_movw_movt(val, x);
2159 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2160 return This::STATUS_OKAY;
2163 // R_ARM_THM_MOVW_ABS_NC: S + A | T
2164 static inline typename This::Status
2165 thm_movw_abs_nc(unsigned char *view,
2166 const Sized_relobj<32, big_endian>* object,
2167 const Symbol_value<32>* psymval,
2168 Arm_address thumb_bit)
2170 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2171 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2172 Valtype* wv = reinterpret_cast<Valtype*>(view);
2173 Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
2174 | elfcpp::Swap<16, big_endian>::readval(wv + 1));
2175 Reltype addend = extract_thumb_movw_movt_addend(val);
2176 Reltype x = psymval->value(object, addend) | thumb_bit;
2177 val = This::insert_val_thumb_movw_movt(val, x);
2178 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
2179 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
2180 return This::STATUS_OKAY;
2183 // R_ARM_THM_MOVT_ABS: S + A
2184 static inline typename This::Status
2185 thm_movt_abs(unsigned char *view,
2186 const Sized_relobj<32, big_endian>* object,
2187 const Symbol_value<32>* psymval)
2189 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2190 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2191 Valtype* wv = reinterpret_cast<Valtype*>(view);
2192 Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
2193 | elfcpp::Swap<16, big_endian>::readval(wv + 1));
2194 Reltype addend = This::extract_thumb_movw_movt_addend(val);
2195 Reltype x = psymval->value(object, addend) >> 16;
2196 val = This::insert_val_thumb_movw_movt(val, x);
2197 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
2198 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
2199 return This::STATUS_OKAY;
2202 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
2203 static inline typename This::Status
2204 movw_prel_nc(unsigned char *view,
2205 const Sized_relobj<32, big_endian>* object,
2206 const Symbol_value<32>* psymval,
2207 Arm_address address,
2208 Arm_address thumb_bit)
2210 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2211 Valtype* wv = reinterpret_cast<Valtype*>(view);
2212 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2213 Valtype addend = This::extract_arm_movw_movt_addend(val);
2214 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
2215 val = This::insert_val_arm_movw_movt(val, x);
2216 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2217 return This::STATUS_OKAY;
2220 // R_ARM_MOVT_PREL: S + A - P
2221 static inline typename This::Status
2222 movt_prel(unsigned char *view,
2223 const Sized_relobj<32, big_endian>* object,
2224 const Symbol_value<32>* psymval,
2225 Arm_address address)
2227 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2228 Valtype* wv = reinterpret_cast<Valtype*>(view);
2229 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2230 Valtype addend = This::extract_arm_movw_movt_addend(val);
2231 Valtype x = (psymval->value(object, addend) - address) >> 16;
2232 val = This::insert_val_arm_movw_movt(val, x);
2233 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2234 return This::STATUS_OKAY;
2237 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
2238 static inline typename This::Status
2239 thm_movw_prel_nc(unsigned char *view,
2240 const Sized_relobj<32, big_endian>* object,
2241 const Symbol_value<32>* psymval,
2242 Arm_address address,
2243 Arm_address thumb_bit)
2245 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2246 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2247 Valtype* wv = reinterpret_cast<Valtype*>(view);
2248 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
2249 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
2250 Reltype addend = This::extract_thumb_movw_movt_addend(val);
2251 Reltype x = (psymval->value(object, addend) | thumb_bit) - address;
2252 val = This::insert_val_thumb_movw_movt(val, x);
2253 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
2254 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
2255 return This::STATUS_OKAY;
2258 // R_ARM_THM_MOVT_PREL: S + A - P
2259 static inline typename This::Status
2260 thm_movt_prel(unsigned char *view,
2261 const Sized_relobj<32, big_endian>* object,
2262 const Symbol_value<32>* psymval,
2263 Arm_address address)
2265 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2266 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2267 Valtype* wv = reinterpret_cast<Valtype*>(view);
2268 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
2269 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
2270 Reltype addend = This::extract_thumb_movw_movt_addend(val);
2271 Reltype x = (psymval->value(object, addend) - address) >> 16;
2272 val = This::insert_val_thumb_movw_movt(val, x);
2273 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
2274 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
2275 return This::STATUS_OKAY;
2279 // Relocate ARM long branches. This handles relocation types
2280 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
2281 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
2282 // undefined and we do not use PLT in this relocation. In such a case,
2283 // the branch is converted into an NOP.
2285 template<bool big_endian>
2286 typename Arm_relocate_functions<big_endian>::Status
2287 Arm_relocate_functions<big_endian>::arm_branch_common(
2288 unsigned int r_type,
2289 const Relocate_info<32, big_endian>* relinfo,
2290 unsigned char *view,
2291 const Sized_symbol<32>* gsym,
2292 const Arm_relobj<big_endian>* object,
2294 const Symbol_value<32>* psymval,
2295 Arm_address address,
2296 Arm_address thumb_bit,
2297 bool is_weakly_undefined_without_plt)
2299 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
2300 Valtype* wv = reinterpret_cast<Valtype*>(view);
2301 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
2303 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
2304 && ((val & 0x0f000000UL) == 0x0a000000UL);
2305 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
2306 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
2307 && ((val & 0x0f000000UL) == 0x0b000000UL);
2308 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
2309 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
2311 // Check that the instruction is valid.
2312 if (r_type == elfcpp::R_ARM_CALL)
2314 if (!insn_is_uncond_bl && !insn_is_blx)
2315 return This::STATUS_BAD_RELOC;
2317 else if (r_type == elfcpp::R_ARM_JUMP24)
2319 if (!insn_is_b && !insn_is_cond_bl)
2320 return This::STATUS_BAD_RELOC;
2322 else if (r_type == elfcpp::R_ARM_PLT32)
2324 if (!insn_is_any_branch)
2325 return This::STATUS_BAD_RELOC;
2327 else if (r_type == elfcpp::R_ARM_XPC25)
2329 // FIXME: AAELF document IH0044C does not say much about it other
2330 // than it being obsolete.
2331 if (!insn_is_any_branch)
2332 return This::STATUS_BAD_RELOC;
2337 // A branch to an undefined weak symbol is turned into a jump to
2338 // the next instruction unless a PLT entry will be created.
2339 // Do the same for local undefined symbols.
2340 // The jump to the next instruction is optimized as a NOP depending
2341 // on the architecture.
2342 const Target_arm<big_endian>* arm_target =
2343 Target_arm<big_endian>::default_target();
2344 if (is_weakly_undefined_without_plt)
2346 Valtype cond = val & 0xf0000000U;
2347 if (arm_target->may_use_arm_nop())
2348 val = cond | 0x0320f000;
2350 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
2351 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2352 return This::STATUS_OKAY;
2355 Valtype addend = utils::sign_extend<26>(val << 2);
2356 Valtype branch_target = psymval->value(object, addend);
2357 int32_t branch_offset = branch_target - address;
2359 // We need a stub if the branch offset is too large or if we need
2361 bool may_use_blx = arm_target->may_use_blx();
2362 Reloc_stub* stub = NULL;
2363 if ((branch_offset > ARM_MAX_FWD_BRANCH_OFFSET)
2364 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
2365 || ((thumb_bit != 0) && !(may_use_blx && r_type == elfcpp::R_ARM_CALL)))
2367 Stub_type stub_type =
2368 Reloc_stub::stub_type_for_reloc(r_type, address, branch_target,
2370 if (stub_type != arm_stub_none)
2372 Stub_table<big_endian>* stub_table =
2373 object->stub_table(relinfo->data_shndx);
2374 gold_assert(stub_table != NULL);
2376 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
2377 stub = stub_table->find_reloc_stub(stub_key);
2378 gold_assert(stub != NULL);
2379 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
2380 branch_target = stub_table->address() + stub->offset() + addend;
2381 branch_offset = branch_target - address;
2382 gold_assert((branch_offset <= ARM_MAX_FWD_BRANCH_OFFSET)
2383 && (branch_offset >= ARM_MAX_BWD_BRANCH_OFFSET));
2387 // At this point, if we still need to switch mode, the instruction
2388 // must either be a BLX or a BL that can be converted to a BLX.
2392 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
2393 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
2396 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
2397 elfcpp::Swap<32, big_endian>::writeval(wv, val);
2398 return (utils::has_overflow<26>(branch_offset)
2399 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
2402 // Relocate THUMB long branches. This handles relocation types
2403 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
2404 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
2405 // undefined and we do not use PLT in this relocation. In such a case,
2406 // the branch is converted into an NOP.
2408 template<bool big_endian>
2409 typename Arm_relocate_functions<big_endian>::Status
2410 Arm_relocate_functions<big_endian>::thumb_branch_common(
2411 unsigned int r_type,
2412 const Relocate_info<32, big_endian>* relinfo,
2413 unsigned char *view,
2414 const Sized_symbol<32>* gsym,
2415 const Arm_relobj<big_endian>* object,
2417 const Symbol_value<32>* psymval,
2418 Arm_address address,
2419 Arm_address thumb_bit,
2420 bool is_weakly_undefined_without_plt)
2422 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2423 Valtype* wv = reinterpret_cast<Valtype*>(view);
2424 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
2425 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
2427 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
2429 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
2430 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
2432 // Check that the instruction is valid.
2433 if (r_type == elfcpp::R_ARM_THM_CALL)
2435 if (!is_bl_insn && !is_blx_insn)
2436 return This::STATUS_BAD_RELOC;
2438 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
2440 // This cannot be a BLX.
2442 return This::STATUS_BAD_RELOC;
2444 else if (r_type == elfcpp::R_ARM_THM_XPC22)
2446 // Check for Thumb to Thumb call.
2448 return This::STATUS_BAD_RELOC;
2451 gold_warning(_("%s: Thumb BLX instruction targets "
2452 "thumb function '%s'."),
2453 object->name().c_str(),
2454 (gsym ? gsym->name() : "(local)"));
2455 // Convert BLX to BL.
2456 lower_insn |= 0x1000U;
2462 // A branch to an undefined weak symbol is turned into a jump to
2463 // the next instruction unless a PLT entry will be created.
2464 // The jump to the next instruction is optimized as a NOP.W for
2465 // Thumb-2 enabled architectures.
2466 const Target_arm<big_endian>* arm_target =
2467 Target_arm<big_endian>::default_target();
2468 if (is_weakly_undefined_without_plt)
2470 if (arm_target->may_use_thumb2_nop())
2472 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
2473 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
2477 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
2478 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
2480 return This::STATUS_OKAY;
2483 // Fetch the addend. We use the Thumb-2 encoding (backwards compatible
2484 // with Thumb-1) involving the J1 and J2 bits.
2485 uint32_t s = (upper_insn & (1 << 10)) >> 10;
2486 uint32_t upper = upper_insn & 0x3ff;
2487 uint32_t lower = lower_insn & 0x7ff;
2488 uint32_t j1 = (lower_insn & (1 << 13)) >> 13;
2489 uint32_t j2 = (lower_insn & (1 << 11)) >> 11;
2490 uint32_t i1 = j1 ^ s ? 0 : 1;
2491 uint32_t i2 = j2 ^ s ? 0 : 1;
2493 int32_t addend = (i1 << 23) | (i2 << 22) | (upper << 12) | (lower << 1);
2495 addend = (addend | ((s ? 0 : 1) << 24)) - (1 << 24);
2497 Arm_address branch_target = psymval->value(object, addend);
2498 int32_t branch_offset = branch_target - address;
2500 // We need a stub if the branch offset is too large or if we need
2502 bool may_use_blx = arm_target->may_use_blx();
2503 bool thumb2 = arm_target->using_thumb2();
2505 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
2506 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
2508 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
2509 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
2510 || ((thumb_bit == 0)
2511 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
2512 || r_type == elfcpp::R_ARM_THM_JUMP24)))
2514 Stub_type stub_type =
2515 Reloc_stub::stub_type_for_reloc(r_type, address, branch_target,
2517 if (stub_type != arm_stub_none)
2519 Stub_table<big_endian>* stub_table =
2520 object->stub_table(relinfo->data_shndx);
2521 gold_assert(stub_table != NULL);
2523 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
2524 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
2525 gold_assert(stub != NULL);
2526 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
2527 branch_target = stub_table->address() + stub->offset() + addend;
2528 branch_offset = branch_target - address;
2532 // At this point, if we still need to switch mode, the instruction
2533 // must either be a BLX or a BL that can be converted to a BLX.
2536 gold_assert(may_use_blx
2537 && (r_type == elfcpp::R_ARM_THM_CALL
2538 || r_type == elfcpp::R_ARM_THM_XPC22));
2539 // Make sure this is a BLX.
2540 lower_insn &= ~0x1000U;
2544 // Make sure this is a BL.
2545 lower_insn |= 0x1000U;
2548 uint32_t reloc_sign = (branch_offset < 0) ? 1 : 0;
2549 uint32_t relocation = static_cast<uint32_t>(branch_offset);
2551 if ((lower_insn & 0x5000U) == 0x4000U)
2552 // For a BLX instruction, make sure that the relocation is rounded up
2553 // to a word boundary. This follows the semantics of the instruction
2554 // which specifies that bit 1 of the target address will come from bit
2555 // 1 of the base address.
2556 relocation = (relocation + 2U) & ~3U;
2558 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
2559 // We use the Thumb-2 encoding, which is safe even if dealing with
2560 // a Thumb-1 instruction by virtue of our overflow check above. */
2561 upper_insn = (upper_insn & ~0x7ffU)
2562 | ((relocation >> 12) & 0x3ffU)
2563 | (reloc_sign << 10);
2564 lower_insn = (lower_insn & ~0x2fffU)
2565 | (((!((relocation >> 23) & 1U)) ^ reloc_sign) << 13)
2566 | (((!((relocation >> 22) & 1U)) ^ reloc_sign) << 11)
2567 | ((relocation >> 1) & 0x7ffU);
2569 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
2570 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
2573 ? utils::has_overflow<25>(relocation)
2574 : utils::has_overflow<23>(relocation))
2575 ? This::STATUS_OVERFLOW
2576 : This::STATUS_OKAY);
2579 // Get the GOT section, creating it if necessary.
2581 template<bool big_endian>
2582 Output_data_got<32, big_endian>*
2583 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
2585 if (this->got_ == NULL)
2587 gold_assert(symtab != NULL && layout != NULL);
2589 this->got_ = new Output_data_got<32, big_endian>();
2592 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
2594 | elfcpp::SHF_WRITE),
2595 this->got_, false, true, true,
2598 // The old GNU linker creates a .got.plt section. We just
2599 // create another set of data in the .got section. Note that we
2600 // always create a PLT if we create a GOT, although the PLT
2602 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
2603 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
2605 | elfcpp::SHF_WRITE),
2606 this->got_plt_, false, false,
2609 // The first three entries are reserved.
2610 this->got_plt_->set_current_data_size(3 * 4);
2612 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
2613 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
2614 Symbol_table::PREDEFINED,
2616 0, 0, elfcpp::STT_OBJECT,
2618 elfcpp::STV_HIDDEN, 0,
2624 // Get the dynamic reloc section, creating it if necessary.
2626 template<bool big_endian>
2627 typename Target_arm<big_endian>::Reloc_section*
2628 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
2630 if (this->rel_dyn_ == NULL)
2632 gold_assert(layout != NULL);
2633 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
2634 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
2635 elfcpp::SHF_ALLOC, this->rel_dyn_, true,
2636 false, false, false);
2638 return this->rel_dyn_;
2641 // Insn_template methods.
2643 // Return byte size of an instruction template.
2646 Insn_template::size() const
2648 switch (this->type())
2661 // Return alignment of an instruction template.
2664 Insn_template::alignment() const
2666 switch (this->type())
2679 // Stub_template methods.
2681 Stub_template::Stub_template(
2682 Stub_type type, const Insn_template* insns,
2684 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
2685 entry_in_thumb_mode_(false), relocs_()
2689 // Compute byte size and alignment of stub template.
2690 for (size_t i = 0; i < insn_count; i++)
2692 unsigned insn_alignment = insns[i].alignment();
2693 size_t insn_size = insns[i].size();
2694 gold_assert((offset & (insn_alignment - 1)) == 0);
2695 this->alignment_ = std::max(this->alignment_, insn_alignment);
2696 switch (insns[i].type())
2698 case Insn_template::THUMB16_TYPE:
2700 this->entry_in_thumb_mode_ = true;
2703 case Insn_template::THUMB32_TYPE:
2704 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
2705 this->relocs_.push_back(Reloc(i, offset));
2707 this->entry_in_thumb_mode_ = true;
2710 case Insn_template::ARM_TYPE:
2711 // Handle cases where the target is encoded within the
2713 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
2714 this->relocs_.push_back(Reloc(i, offset));
2717 case Insn_template::DATA_TYPE:
2718 // Entry point cannot be data.
2719 gold_assert(i != 0);
2720 this->relocs_.push_back(Reloc(i, offset));
2726 offset += insn_size;
2728 this->size_ = offset;
2731 // Reloc_stub::Key methods.
2733 // Dump a Key as a string for debugging.
2736 Reloc_stub::Key::name() const
2738 if (this->r_sym_ == invalid_index)
2740 // Global symbol key name
2741 // <stub-type>:<symbol name>:<addend>.
2742 const std::string sym_name = this->u_.symbol->name();
2743 // We need to print two hex number and two colons. So just add 100 bytes
2744 // to the symbol name size.
2745 size_t len = sym_name.size() + 100;
2746 char* buffer = new char[len];
2747 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
2748 sym_name.c_str(), this->addend_);
2749 gold_assert(c > 0 && c < static_cast<int>(len));
2751 return std::string(buffer);
2755 // local symbol key name
2756 // <stub-type>:<object>:<r_sym>:<addend>.
2757 const size_t len = 200;
2759 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
2760 this->u_.relobj, this->r_sym_, this->addend_);
2761 gold_assert(c > 0 && c < static_cast<int>(len));
2762 return std::string(buffer);
2766 // Reloc_stub methods.
2768 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
2769 // LOCATION to DESTINATION.
2770 // This code is based on the arm_type_of_stub function in
2771 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
2775 Reloc_stub::stub_type_for_reloc(
2776 unsigned int r_type,
2777 Arm_address location,
2778 Arm_address destination,
2779 bool target_is_thumb)
2781 Stub_type stub_type = arm_stub_none;
2783 // This is a bit ugly but we want to avoid using a templated class for
2784 // big and little endianities.
2786 bool should_force_pic_veneer;
2789 if (parameters->target().is_big_endian())
2791 const Target_arm<true>* big_endian_target =
2792 Target_arm<true>::default_target();
2793 may_use_blx = big_endian_target->may_use_blx();
2794 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
2795 thumb2 = big_endian_target->using_thumb2();
2796 thumb_only = big_endian_target->using_thumb_only();
2800 const Target_arm<false>* little_endian_target =
2801 Target_arm<false>::default_target();
2802 may_use_blx = little_endian_target->may_use_blx();
2803 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
2804 thumb2 = little_endian_target->using_thumb2();
2805 thumb_only = little_endian_target->using_thumb_only();
2808 int64_t branch_offset = (int64_t)destination - location;
2810 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
2812 // Handle cases where:
2813 // - this call goes too far (different Thumb/Thumb2 max
2815 // - it's a Thumb->Arm call and blx is not available, or it's a
2816 // Thumb->Arm branch (not bl). A stub is needed in this case.
2818 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
2819 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
2821 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
2822 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
2823 || ((!target_is_thumb)
2824 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
2825 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
2827 if (target_is_thumb)
2832 stub_type = (parameters->options().shared()
2833 || should_force_pic_veneer)
2836 && (r_type == elfcpp::R_ARM_THM_CALL))
2837 // V5T and above. Stub starts with ARM code, so
2838 // we must be able to switch mode before
2839 // reaching it, which is only possible for 'bl'
2840 // (ie R_ARM_THM_CALL relocation).
2841 ? arm_stub_long_branch_any_thumb_pic
2842 // On V4T, use Thumb code only.
2843 : arm_stub_long_branch_v4t_thumb_thumb_pic)
2847 && (r_type == elfcpp::R_ARM_THM_CALL))
2848 ? arm_stub_long_branch_any_any // V5T and above.
2849 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
2853 stub_type = (parameters->options().shared()
2854 || should_force_pic_veneer)
2855 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
2856 : arm_stub_long_branch_thumb_only; // non-PIC stub.
2863 // FIXME: We should check that the input section is from an
2864 // object that has interwork enabled.
2866 stub_type = (parameters->options().shared()
2867 || should_force_pic_veneer)
2870 && (r_type == elfcpp::R_ARM_THM_CALL))
2871 ? arm_stub_long_branch_any_arm_pic // V5T and above.
2872 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
2876 && (r_type == elfcpp::R_ARM_THM_CALL))
2877 ? arm_stub_long_branch_any_any // V5T and above.
2878 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
2880 // Handle v4t short branches.
2881 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
2882 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
2883 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
2884 stub_type = arm_stub_short_branch_v4t_thumb_arm;
2888 else if (r_type == elfcpp::R_ARM_CALL
2889 || r_type == elfcpp::R_ARM_JUMP24
2890 || r_type == elfcpp::R_ARM_PLT32)
2892 if (target_is_thumb)
2896 // FIXME: We should check that the input section is from an
2897 // object that has interwork enabled.
2899 // We have an extra 2-bytes reach because of
2900 // the mode change (bit 24 (H) of BLX encoding).
2901 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
2902 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
2903 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
2904 || (r_type == elfcpp::R_ARM_JUMP24)
2905 || (r_type == elfcpp::R_ARM_PLT32))
2907 stub_type = (parameters->options().shared()
2908 || should_force_pic_veneer)
2911 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
2912 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
2916 ? arm_stub_long_branch_any_any // V5T and above.
2917 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
2923 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
2924 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
2926 stub_type = (parameters->options().shared()
2927 || should_force_pic_veneer)
2928 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
2929 : arm_stub_long_branch_any_any; /// non-PIC.
2937 // Template to implement do_write for a specific target endianity.
2939 template<bool big_endian>
2941 Reloc_stub::do_fixed_endian_write(unsigned char* view,
2942 section_size_type view_size)
2944 const Stub_template* stub_template = this->stub_template();
2945 const Insn_template* insns = stub_template->insns();
2947 // FIXME: We do not handle BE8 encoding yet.
2948 unsigned char* pov = view;
2949 for (size_t i = 0; i < stub_template->insn_count(); i++)
2951 switch (insns[i].type())
2953 case Insn_template::THUMB16_TYPE:
2954 // Non-zero reloc addends are only used in Cortex-A8 stubs.
2955 gold_assert(insns[i].reloc_addend() == 0);
2956 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
2958 case Insn_template::THUMB32_TYPE:
2960 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
2961 uint32_t lo = insns[i].data() & 0xffff;
2962 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
2963 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
2966 case Insn_template::ARM_TYPE:
2967 case Insn_template::DATA_TYPE:
2968 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
2973 pov += insns[i].size();
2975 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
2978 // Write a reloc stub to VIEW with endianity specified by BIG_ENDIAN.
2981 Reloc_stub::do_write(unsigned char* view, section_size_type view_size,
2985 this->do_fixed_endian_write<true>(view, view_size);
2987 this->do_fixed_endian_write<false>(view, view_size);
2990 // Stub_factory methods.
2992 Stub_factory::Stub_factory()
2994 // The instruction template sequences are declared as static
2995 // objects and initialized first time the constructor runs.
2997 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
2998 // to reach the stub if necessary.
2999 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
3001 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
3002 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
3003 // dcd R_ARM_ABS32(X)
3006 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
3008 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
3010 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3011 Insn_template::arm_insn(0xe12fff1c), // bx ip
3012 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
3013 // dcd R_ARM_ABS32(X)
3016 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
3017 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
3019 Insn_template::thumb16_insn(0xb401), // push {r0}
3020 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
3021 Insn_template::thumb16_insn(0x4684), // mov ip, r0
3022 Insn_template::thumb16_insn(0xbc01), // pop {r0}
3023 Insn_template::thumb16_insn(0x4760), // bx ip
3024 Insn_template::thumb16_insn(0xbf00), // nop
3025 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
3026 // dcd R_ARM_ABS32(X)
3029 // V4T Thumb -> Thumb long branch stub. Using the stack is not
3031 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
3033 Insn_template::thumb16_insn(0x4778), // bx pc
3034 Insn_template::thumb16_insn(0x46c0), // nop
3035 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3036 Insn_template::arm_insn(0xe12fff1c), // bx ip
3037 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
3038 // dcd R_ARM_ABS32(X)
3041 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
3043 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
3045 Insn_template::thumb16_insn(0x4778), // bx pc
3046 Insn_template::thumb16_insn(0x46c0), // nop
3047 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
3048 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
3049 // dcd R_ARM_ABS32(X)
3052 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
3053 // one, when the destination is close enough.
3054 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
3056 Insn_template::thumb16_insn(0x4778), // bx pc
3057 Insn_template::thumb16_insn(0x46c0), // nop
3058 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
3061 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
3062 // blx to reach the stub if necessary.
3063 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
3065 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
3066 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
3067 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
3068 // dcd R_ARM_REL32(X-4)
3071 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
3072 // blx to reach the stub if necessary. We can not add into pc;
3073 // it is not guaranteed to mode switch (different in ARMv6 and
3075 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
3077 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
3078 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3079 Insn_template::arm_insn(0xe12fff1c), // bx ip
3080 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
3081 // dcd R_ARM_REL32(X)
3084 // V4T ARM -> ARM long branch stub, PIC.
3085 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
3087 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
3088 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3089 Insn_template::arm_insn(0xe12fff1c), // bx ip
3090 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
3091 // dcd R_ARM_REL32(X)
3094 // V4T Thumb -> ARM long branch stub, PIC.
3095 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
3097 Insn_template::thumb16_insn(0x4778), // bx pc
3098 Insn_template::thumb16_insn(0x46c0), // nop
3099 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3100 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
3101 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
3102 // dcd R_ARM_REL32(X)
3105 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
3107 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
3109 Insn_template::thumb16_insn(0xb401), // push {r0}
3110 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
3111 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
3112 Insn_template::thumb16_insn(0x4484), // add ip, r0
3113 Insn_template::thumb16_insn(0xbc01), // pop {r0}
3114 Insn_template::thumb16_insn(0x4760), // bx ip
3115 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
3116 // dcd R_ARM_REL32(X)
3119 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
3121 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
3123 Insn_template::thumb16_insn(0x4778), // bx pc
3124 Insn_template::thumb16_insn(0x46c0), // nop
3125 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
3126 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3127 Insn_template::arm_insn(0xe12fff1c), // bx ip
3128 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
3129 // dcd R_ARM_REL32(X)
3132 // Cortex-A8 erratum-workaround stubs.
3134 // Stub used for conditional branches (which may be beyond +/-1MB away,
3135 // so we can't use a conditional branch to reach this stub).
3142 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
3144 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
3145 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
3146 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
3150 // Stub used for b.w and bl.w instructions.
3152 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
3154 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
3157 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
3159 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
3162 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
3163 // instruction (which switches to ARM mode) to point to this stub. Jump to
3164 // the real destination using an ARM-mode branch.
3165 const Insn_template elf32_arm_stub_a8_veneer_blx[] =
3167 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
3170 // Fill in the stub template look-up table. Stub templates are constructed
3171 // per instance of Stub_factory for fast look-up without locking
3172 // in a thread-enabled environment.
3174 this->stub_templates_[arm_stub_none] =
3175 new Stub_template(arm_stub_none, NULL, 0);
3177 #define DEF_STUB(x) \
3181 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
3182 Stub_type type = arm_stub_##x; \
3183 this->stub_templates_[type] = \
3184 new Stub_template(type, elf32_arm_stub_##x, array_size); \
3192 // Stub_table methods.
3194 // Add a STUB with using KEY. Caller is reponsible for avoid adding
3195 // if already a STUB with the same key has been added.
3197 template<bool big_endian>
3199 Stub_table<big_endian>::add_reloc_stub(
3201 const Reloc_stub::Key& key)
3203 const Stub_template* stub_template = stub->stub_template();
3204 gold_assert(stub_template->type() == key.stub_type());
3205 this->reloc_stubs_[key] = stub;
3206 if (this->addralign_ < stub_template->alignment())
3207 this->addralign_ = stub_template->alignment();
3208 this->has_been_changed_ = true;
3211 template<bool big_endian>
3213 Stub_table<big_endian>::relocate_stubs(
3214 const Relocate_info<32, big_endian>* relinfo,
3215 Target_arm<big_endian>* arm_target,
3216 Output_section* output_section,
3217 unsigned char* view,
3218 Arm_address address,
3219 section_size_type view_size)
3221 // If we are passed a view bigger than the stub table's. we need to
3223 gold_assert(address == this->address()
3225 == static_cast<section_size_type>(this->data_size())));
3227 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
3228 p != this->reloc_stubs_.end();
3231 Reloc_stub* stub = p->second;
3232 const Stub_template* stub_template = stub->stub_template();
3233 if (stub_template->reloc_count() != 0)
3235 // Adjust view to cover the stub only.
3236 section_size_type offset = stub->offset();
3237 section_size_type stub_size = stub_template->size();
3238 gold_assert(offset + stub_size <= view_size);
3240 arm_target->relocate_stub(stub, relinfo, output_section,
3241 view + offset, address + offset,
3247 // Reset address and file offset.
3249 template<bool big_endian>
3251 Stub_table<big_endian>::do_reset_address_and_file_offset()
3254 uint64_t max_addralign = 1;
3255 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
3256 p != this->reloc_stubs_.end();
3259 Reloc_stub* stub = p->second;
3260 const Stub_template* stub_template = stub->stub_template();
3261 uint64_t stub_addralign = stub_template->alignment();
3262 max_addralign = std::max(max_addralign, stub_addralign);
3263 off = align_address(off, stub_addralign);
3264 stub->set_offset(off);
3265 stub->reset_destination_address();
3266 off += stub_template->size();
3269 this->addralign_ = max_addralign;
3270 this->set_current_data_size_for_child(off);
3273 // Write out the stubs to file.
3275 template<bool big_endian>
3277 Stub_table<big_endian>::do_write(Output_file* of)
3279 off_t offset = this->offset();
3280 const section_size_type oview_size =
3281 convert_to_section_size_type(this->data_size());
3282 unsigned char* const oview = of->get_output_view(offset, oview_size);
3284 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
3285 p != this->reloc_stubs_.end();
3288 Reloc_stub* stub = p->second;
3289 Arm_address address = this->address() + stub->offset();
3291 == align_address(address,
3292 stub->stub_template()->alignment()));
3293 stub->write(oview + stub->offset(), stub->stub_template()->size(),
3296 of->write_output_view(this->offset(), oview_size, oview);
3299 // Arm_input_section methods.
3301 // Initialize an Arm_input_section.
3303 template<bool big_endian>
3305 Arm_input_section<big_endian>::init()
3307 Relobj* relobj = this->relobj();
3308 unsigned int shndx = this->shndx();
3310 // Cache these to speed up size and alignment queries. It is too slow
3311 // to call section_addraglin and section_size every time.
3312 this->original_addralign_ = relobj->section_addralign(shndx);
3313 this->original_size_ = relobj->section_size(shndx);
3315 // We want to make this look like the original input section after
3316 // output sections are finalized.
3317 Output_section* os = relobj->output_section(shndx);
3318 off_t offset = relobj->output_section_offset(shndx);
3319 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
3320 this->set_address(os->address() + offset);
3321 this->set_file_offset(os->offset() + offset);
3323 this->set_current_data_size(this->original_size_);
3324 this->finalize_data_size();
3327 template<bool big_endian>
3329 Arm_input_section<big_endian>::do_write(Output_file* of)
3331 // We have to write out the original section content.
3332 section_size_type section_size;
3333 const unsigned char* section_contents =
3334 this->relobj()->section_contents(this->shndx(), §ion_size, false);
3335 of->write(this->offset(), section_contents, section_size);
3337 // If this owns a stub table and it is not empty, write it.
3338 if (this->is_stub_table_owner() && !this->stub_table_->empty())
3339 this->stub_table_->write(of);
3342 // Finalize data size.
3344 template<bool big_endian>
3346 Arm_input_section<big_endian>::set_final_data_size()
3348 // If this owns a stub table, finalize its data size as well.
3349 if (this->is_stub_table_owner())
3351 uint64_t address = this->address();
3353 // The stub table comes after the original section contents.
3354 address += this->original_size_;
3355 address = align_address(address, this->stub_table_->addralign());
3356 off_t offset = this->offset() + (address - this->address());
3357 this->stub_table_->set_address_and_file_offset(address, offset);
3358 address += this->stub_table_->data_size();
3359 gold_assert(address == this->address() + this->current_data_size());
3362 this->set_data_size(this->current_data_size());
3365 // Reset address and file offset.
3367 template<bool big_endian>
3369 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
3371 // Size of the original input section contents.
3372 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
3374 // If this is a stub table owner, account for the stub table size.
3375 if (this->is_stub_table_owner())
3377 Stub_table<big_endian>* stub_table = this->stub_table_;
3379 // Reset the stub table's address and file offset. The
3380 // current data size for child will be updated after that.
3381 stub_table_->reset_address_and_file_offset();
3382 off = align_address(off, stub_table_->addralign());
3383 off += stub_table->current_data_size();
3386 this->set_current_data_size(off);
3389 // Arm_output_section methods.
3391 // Create a stub group for input sections from BEGIN to END. OWNER
3392 // points to the input section to be the owner a new stub table.
3394 template<bool big_endian>
3396 Arm_output_section<big_endian>::create_stub_group(
3397 Input_section_list::const_iterator begin,
3398 Input_section_list::const_iterator end,
3399 Input_section_list::const_iterator owner,
3400 Target_arm<big_endian>* target,
3401 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
3403 // Currently we convert ordinary input sections into relaxed sections only
3404 // at this point but we may want to support creating relaxed input section
3405 // very early. So we check here to see if owner is already a relaxed
3408 Arm_input_section<big_endian>* arm_input_section;
3409 if (owner->is_relaxed_input_section())
3412 Arm_input_section<big_endian>::as_arm_input_section(
3413 owner->relaxed_input_section());
3417 gold_assert(owner->is_input_section());
3418 // Create a new relaxed input section.
3420 target->new_arm_input_section(owner->relobj(), owner->shndx());
3421 new_relaxed_sections->push_back(arm_input_section);
3424 // Create a stub table.
3425 Stub_table<big_endian>* stub_table =
3426 target->new_stub_table(arm_input_section);
3428 arm_input_section->set_stub_table(stub_table);
3430 Input_section_list::const_iterator p = begin;
3431 Input_section_list::const_iterator prev_p;
3433 // Look for input sections or relaxed input sections in [begin ... end].
3436 if (p->is_input_section() || p->is_relaxed_input_section())
3438 // The stub table information for input sections live
3439 // in their objects.
3440 Arm_relobj<big_endian>* arm_relobj =
3441 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
3442 arm_relobj->set_stub_table(p->shndx(), stub_table);
3446 while (prev_p != end);
3449 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
3450 // of stub groups. We grow a stub group by adding input section until the
3451 // size is just below GROUP_SIZE. The last input section will be converted
3452 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
3453 // input section after the stub table, effectively double the group size.
3455 // This is similar to the group_sections() function in elf32-arm.c but is
3456 // implemented differently.
3458 template<bool big_endian>
3460 Arm_output_section<big_endian>::group_sections(
3461 section_size_type group_size,
3462 bool stubs_always_after_branch,
3463 Target_arm<big_endian>* target)
3465 // We only care about sections containing code.
3466 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
3469 // States for grouping.
3472 // No group is being built.
3474 // A group is being built but the stub table is not found yet.
3475 // We keep group a stub group until the size is just under GROUP_SIZE.
3476 // The last input section in the group will be used as the stub table.
3477 FINDING_STUB_SECTION,
3478 // A group is being built and we have already found a stub table.
3479 // We enter this state to grow a stub group by adding input section
3480 // after the stub table. This effectively doubles the group size.
3484 // Any newly created relaxed sections are stored here.
3485 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
3487 State state = NO_GROUP;
3488 section_size_type off = 0;
3489 section_size_type group_begin_offset = 0;
3490 section_size_type group_end_offset = 0;
3491 section_size_type stub_table_end_offset = 0;
3492 Input_section_list::const_iterator group_begin =
3493 this->input_sections().end();
3494 Input_section_list::const_iterator stub_table =
3495 this->input_sections().end();
3496 Input_section_list::const_iterator group_end = this->input_sections().end();
3497 for (Input_section_list::const_iterator p = this->input_sections().begin();
3498 p != this->input_sections().end();
3501 section_size_type section_begin_offset =
3502 align_address(off, p->addralign());
3503 section_size_type section_end_offset =
3504 section_begin_offset + p->data_size();
3506 // Check to see if we should group the previously seens sections.
3512 case FINDING_STUB_SECTION:
3513 // Adding this section makes the group larger than GROUP_SIZE.
3514 if (section_end_offset - group_begin_offset >= group_size)
3516 if (stubs_always_after_branch)
3518 gold_assert(group_end != this->input_sections().end());
3519 this->create_stub_group(group_begin, group_end, group_end,
3520 target, &new_relaxed_sections);
3525 // But wait, there's more! Input sections up to
3526 // stub_group_size bytes after the stub table can be
3527 // handled by it too.
3528 state = HAS_STUB_SECTION;
3529 stub_table = group_end;
3530 stub_table_end_offset = group_end_offset;
3535 case HAS_STUB_SECTION:
3536 // Adding this section makes the post stub-section group larger
3538 if (section_end_offset - stub_table_end_offset >= group_size)
3540 gold_assert(group_end != this->input_sections().end());
3541 this->create_stub_group(group_begin, group_end, stub_table,
3542 target, &new_relaxed_sections);
3551 // If we see an input section and currently there is no group, start
3552 // a new one. Skip any empty sections.
3553 if ((p->is_input_section() || p->is_relaxed_input_section())
3554 && (p->relobj()->section_size(p->shndx()) != 0))
3556 if (state == NO_GROUP)
3558 state = FINDING_STUB_SECTION;
3560 group_begin_offset = section_begin_offset;
3563 // Keep track of the last input section seen.
3565 group_end_offset = section_end_offset;
3568 off = section_end_offset;
3571 // Create a stub group for any ungrouped sections.
3572 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
3574 gold_assert(group_end != this->input_sections().end());
3575 this->create_stub_group(group_begin, group_end,
3576 (state == FINDING_STUB_SECTION
3579 target, &new_relaxed_sections);
3582 // Convert input section into relaxed input section in a batch.
3583 if (!new_relaxed_sections.empty())
3584 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
3586 // Update the section offsets
3587 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
3589 Arm_relobj<big_endian>* arm_relobj =
3590 Arm_relobj<big_endian>::as_arm_relobj(
3591 new_relaxed_sections[i]->relobj());
3592 unsigned int shndx = new_relaxed_sections[i]->shndx();
3593 // Tell Arm_relobj that this input section is converted.
3594 arm_relobj->convert_input_section_to_relaxed_section(shndx);
3598 // Arm_relobj methods.
3600 // Scan relocations for stub generation.
3602 template<bool big_endian>
3604 Arm_relobj<big_endian>::scan_sections_for_stubs(
3605 Target_arm<big_endian>* arm_target,
3606 const Symbol_table* symtab,
3607 const Layout* layout)
3609 unsigned int shnum = this->shnum();
3610 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
3612 // Read the section headers.
3613 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
3617 // To speed up processing, we set up hash tables for fast lookup of
3618 // input offsets to output addresses.
3619 this->initialize_input_to_output_maps();
3621 const Relobj::Output_sections& out_sections(this->output_sections());
3623 Relocate_info<32, big_endian> relinfo;
3624 relinfo.symtab = symtab;
3625 relinfo.layout = layout;
3626 relinfo.object = this;
3628 const unsigned char* p = pshdrs + shdr_size;
3629 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
3631 typename elfcpp::Shdr<32, big_endian> shdr(p);
3633 unsigned int sh_type = shdr.get_sh_type();
3634 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
3637 off_t sh_size = shdr.get_sh_size();
3641 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
3642 if (index >= this->shnum())
3644 // Ignore reloc section with bad info. This error will be
3645 // reported in the final link.
3649 Output_section* os = out_sections[index];
3651 || symtab->is_section_folded(this, index))
3653 // This relocation section is against a section which we
3654 // discarded or if the section is folded into another
3655 // section due to ICF.
3658 Arm_address output_offset = this->get_output_section_offset(index);
3660 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
3662 // Ignore reloc section with unexpected symbol table. The
3663 // error will be reported in the final link.
3667 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
3668 sh_size, true, false);
3670 unsigned int reloc_size;
3671 if (sh_type == elfcpp::SHT_REL)
3672 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
3674 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
3676 if (reloc_size != shdr.get_sh_entsize())
3678 // Ignore reloc section with unexpected entsize. The error
3679 // will be reported in the final link.
3683 size_t reloc_count = sh_size / reloc_size;
3684 if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
3686 // Ignore reloc section with uneven size. The error will be
3687 // reported in the final link.
3691 gold_assert(output_offset != invalid_address
3692 || this->relocs_must_follow_section_writes());
3694 // Get the section contents. This does work for the case in which
3695 // we modify the contents of an input section. We need to pass the
3696 // output view under such circumstances.
3697 section_size_type input_view_size = 0;
3698 const unsigned char* input_view =
3699 this->section_contents(index, &input_view_size, false);
3701 relinfo.reloc_shndx = i;
3702 relinfo.data_shndx = index;
3703 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
3705 output_offset == invalid_address,
3711 // After we've done the relocations, we release the hash tables,
3712 // since we no longer need them.
3713 this->free_input_to_output_maps();
3716 // Count the local symbols. The ARM backend needs to know if a symbol
3717 // is a THUMB function or not. For global symbols, it is easy because
3718 // the Symbol object keeps the ELF symbol type. For local symbol it is
3719 // harder because we cannot access this information. So we override the
3720 // do_count_local_symbol in parent and scan local symbols to mark
3721 // THUMB functions. This is not the most efficient way but I do not want to
3722 // slow down other ports by calling a per symbol targer hook inside
3723 // Sized_relobj<size, big_endian>::do_count_local_symbols.
3725 template<bool big_endian>
3727 Arm_relobj<big_endian>::do_count_local_symbols(
3728 Stringpool_template<char>* pool,
3729 Stringpool_template<char>* dynpool)
3731 // We need to fix-up the values of any local symbols whose type are
3734 // Ask parent to count the local symbols.
3735 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
3736 const unsigned int loccount = this->local_symbol_count();
3740 // Intialize the thumb function bit-vector.
3741 std::vector<bool> empty_vector(loccount, false);
3742 this->local_symbol_is_thumb_function_.swap(empty_vector);
3744 // Read the symbol table section header.
3745 const unsigned int symtab_shndx = this->symtab_shndx();
3746 elfcpp::Shdr<32, big_endian>
3747 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
3748 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
3750 // Read the local symbols.
3751 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
3752 gold_assert(loccount == symtabshdr.get_sh_info());
3753 off_t locsize = loccount * sym_size;
3754 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
3755 locsize, true, true);
3757 // Loop over the local symbols and mark any local symbols pointing
3758 // to THUMB functions.
3760 // Skip the first dummy symbol.
3762 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
3763 this->local_values();
3764 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
3766 elfcpp::Sym<32, big_endian> sym(psyms);
3767 elfcpp::STT st_type = sym.get_st_type();
3768 Symbol_value<32>& lv((*plocal_values)[i]);
3769 Arm_address input_value = lv.input_value();
3771 if (st_type == elfcpp::STT_ARM_TFUNC
3772 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
3774 // This is a THUMB function. Mark this and canonicalize the
3775 // symbol value by setting LSB.
3776 this->local_symbol_is_thumb_function_[i] = true;
3777 if ((input_value & 1) == 0)
3778 lv.set_input_value(input_value | 1);
3783 // Relocate sections.
3784 template<bool big_endian>
3786 Arm_relobj<big_endian>::do_relocate_sections(
3787 const Symbol_table* symtab,
3788 const Layout* layout,
3789 const unsigned char* pshdrs,
3790 typename Sized_relobj<32, big_endian>::Views* pviews)
3792 // Call parent to relocate sections.
3793 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
3796 // We do not generate stubs if doing a relocatable link.
3797 if (parameters->options().relocatable())
3800 // Relocate stub tables.
3801 unsigned int shnum = this->shnum();
3803 Target_arm<big_endian>* arm_target =
3804 Target_arm<big_endian>::default_target();
3806 Relocate_info<32, big_endian> relinfo;
3807 relinfo.symtab = symtab;
3808 relinfo.layout = layout;
3809 relinfo.object = this;
3811 for (unsigned int i = 1; i < shnum; ++i)
3813 Arm_input_section<big_endian>* arm_input_section =
3814 arm_target->find_arm_input_section(this, i);
3816 if (arm_input_section == NULL
3817 || !arm_input_section->is_stub_table_owner()
3818 || arm_input_section->stub_table()->empty())
3821 // We cannot discard a section if it owns a stub table.
3822 Output_section* os = this->output_section(i);
3823 gold_assert(os != NULL);
3825 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
3826 relinfo.reloc_shdr = NULL;
3827 relinfo.data_shndx = i;
3828 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
3830 gold_assert((*pviews)[i].view != NULL);
3832 // We are passed the output section view. Adjust it to cover the
3834 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
3835 gold_assert((stub_table->address() >= (*pviews)[i].address)
3836 && ((stub_table->address() + stub_table->data_size())
3837 <= (*pviews)[i].address + (*pviews)[i].view_size));
3839 off_t offset = stub_table->address() - (*pviews)[i].address;
3840 unsigned char* view = (*pviews)[i].view + offset;
3841 Arm_address address = stub_table->address();
3842 section_size_type view_size = stub_table->data_size();
3844 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
3849 // Helper functions for both Arm_relobj and Arm_dynobj to read ARM
3852 template<bool big_endian>
3853 Attributes_section_data*
3854 read_arm_attributes_section(
3856 Read_symbols_data *sd)
3858 // Read the attributes section if there is one.
3859 // We read from the end because gas seems to put it near the end of
3860 // the section headers.
3861 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
3862 const unsigned char *ps =
3863 sd->section_headers->data() + shdr_size * (object->shnum() - 1);
3864 for (unsigned int i = object->shnum(); i > 0; --i, ps -= shdr_size)
3866 elfcpp::Shdr<32, big_endian> shdr(ps);
3867 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
3869 section_offset_type section_offset = shdr.get_sh_offset();
3870 section_size_type section_size =
3871 convert_to_section_size_type(shdr.get_sh_size());
3872 File_view* view = object->get_lasting_view(section_offset,
3873 section_size, true, false);
3874 return new Attributes_section_data(view->data(), section_size);
3880 // Read the symbol information.
3882 template<bool big_endian>
3884 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
3886 // Call parent class to read symbol information.
3887 Sized_relobj<32, big_endian>::do_read_symbols(sd);
3889 // Read processor-specific flags in ELF file header.
3890 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
3891 elfcpp::Elf_sizes<32>::ehdr_size,
3893 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
3894 this->processor_specific_flags_ = ehdr.get_e_flags();
3895 this->attributes_section_data_ =
3896 read_arm_attributes_section<big_endian>(this, sd);
3899 // Arm_dynobj methods.
3901 // Read the symbol information.
3903 template<bool big_endian>
3905 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
3907 // Call parent class to read symbol information.
3908 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
3910 // Read processor-specific flags in ELF file header.
3911 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
3912 elfcpp::Elf_sizes<32>::ehdr_size,
3914 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
3915 this->processor_specific_flags_ = ehdr.get_e_flags();
3916 this->attributes_section_data_ =
3917 read_arm_attributes_section<big_endian>(this, sd);
3920 // Stub_addend_reader methods.
3922 // Read the addend of a REL relocation of type R_TYPE at VIEW.
3924 template<bool big_endian>
3925 elfcpp::Elf_types<32>::Elf_Swxword
3926 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
3927 unsigned int r_type,
3928 const unsigned char* view,
3929 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
3933 case elfcpp::R_ARM_CALL:
3934 case elfcpp::R_ARM_JUMP24:
3935 case elfcpp::R_ARM_PLT32:
3937 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3938 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
3939 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3940 return utils::sign_extend<26>(val << 2);
3943 case elfcpp::R_ARM_THM_CALL:
3944 case elfcpp::R_ARM_THM_JUMP24:
3945 case elfcpp::R_ARM_THM_XPC22:
3947 // Fetch the addend. We use the Thumb-2 encoding (backwards
3948 // compatible with Thumb-1) involving the J1 and J2 bits.
3949 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3950 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
3951 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3952 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3954 uint32_t s = (upper_insn & (1 << 10)) >> 10;
3955 uint32_t upper = upper_insn & 0x3ff;
3956 uint32_t lower = lower_insn & 0x7ff;
3957 uint32_t j1 = (lower_insn & (1 << 13)) >> 13;
3958 uint32_t j2 = (lower_insn & (1 << 11)) >> 11;
3959 uint32_t i1 = j1 ^ s ? 0 : 1;
3960 uint32_t i2 = j2 ^ s ? 0 : 1;
3962 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
3963 | (upper << 12) | (lower << 1));
3966 case elfcpp::R_ARM_THM_JUMP19:
3968 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3969 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
3970 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3971 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3973 // Reconstruct the top three bits and squish the two 11 bit pieces
3975 uint32_t S = (upper_insn & 0x0400) >> 10;
3976 uint32_t J1 = (lower_insn & 0x2000) >> 13;
3977 uint32_t J2 = (lower_insn & 0x0800) >> 11;
3979 (S << 8) | (J2 << 7) | (J1 << 6) | (upper_insn & 0x003f);
3980 uint32_t lower = (lower_insn & 0x07ff);
3981 return utils::sign_extend<23>((upper << 12) | (lower << 1));
3989 // A class to handle the PLT data.
3991 template<bool big_endian>
3992 class Output_data_plt_arm : public Output_section_data
3995 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
3998 Output_data_plt_arm(Layout*, Output_data_space*);
4000 // Add an entry to the PLT.
4002 add_entry(Symbol* gsym);
4004 // Return the .rel.plt section data.
4005 const Reloc_section*
4007 { return this->rel_; }
4011 do_adjust_output_section(Output_section* os);
4013 // Write to a map file.
4015 do_print_to_mapfile(Mapfile* mapfile) const
4016 { mapfile->print_output_data(this, _("** PLT")); }
4019 // Template for the first PLT entry.
4020 static const uint32_t first_plt_entry[5];
4022 // Template for subsequent PLT entries.
4023 static const uint32_t plt_entry[3];
4025 // Set the final size.
4027 set_final_data_size()
4029 this->set_data_size(sizeof(first_plt_entry)
4030 + this->count_ * sizeof(plt_entry));
4033 // Write out the PLT data.
4035 do_write(Output_file*);
4037 // The reloc section.
4038 Reloc_section* rel_;
4039 // The .got.plt section.
4040 Output_data_space* got_plt_;
4041 // The number of PLT entries.
4042 unsigned int count_;
4045 // Create the PLT section. The ordinary .got section is an argument,
4046 // since we need to refer to the start. We also create our own .got
4047 // section just for PLT entries.
4049 template<bool big_endian>
4050 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
4051 Output_data_space* got_plt)
4052 : Output_section_data(4), got_plt_(got_plt), count_(0)
4054 this->rel_ = new Reloc_section(false);
4055 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
4056 elfcpp::SHF_ALLOC, this->rel_, true, false,
4060 template<bool big_endian>
4062 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
4067 // Add an entry to the PLT.
4069 template<bool big_endian>
4071 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
4073 gold_assert(!gsym->has_plt_offset());
4075 // Note that when setting the PLT offset we skip the initial
4076 // reserved PLT entry.
4077 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
4078 + sizeof(first_plt_entry));
4082 section_offset_type got_offset = this->got_plt_->current_data_size();
4084 // Every PLT entry needs a GOT entry which points back to the PLT
4085 // entry (this will be changed by the dynamic linker, normally
4086 // lazily when the function is called).
4087 this->got_plt_->set_current_data_size(got_offset + 4);
4089 // Every PLT entry needs a reloc.
4090 gsym->set_needs_dynsym_entry();
4091 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
4094 // Note that we don't need to save the symbol. The contents of the
4095 // PLT are independent of which symbols are used. The symbols only
4096 // appear in the relocations.
4100 // FIXME: This is not very flexible. Right now this has only been tested
4101 // on armv5te. If we are to support additional architecture features like
4102 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
4104 // The first entry in the PLT.
4105 template<bool big_endian>
4106 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
4108 0xe52de004, // str lr, [sp, #-4]!
4109 0xe59fe004, // ldr lr, [pc, #4]
4110 0xe08fe00e, // add lr, pc, lr
4111 0xe5bef008, // ldr pc, [lr, #8]!
4112 0x00000000, // &GOT[0] - .
4115 // Subsequent entries in the PLT.
4117 template<bool big_endian>
4118 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
4120 0xe28fc600, // add ip, pc, #0xNN00000
4121 0xe28cca00, // add ip, ip, #0xNN000
4122 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
4125 // Write out the PLT. This uses the hand-coded instructions above,
4126 // and adjusts them as needed. This is all specified by the arm ELF
4127 // Processor Supplement.
4129 template<bool big_endian>
4131 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
4133 const off_t offset = this->offset();
4134 const section_size_type oview_size =
4135 convert_to_section_size_type(this->data_size());
4136 unsigned char* const oview = of->get_output_view(offset, oview_size);
4138 const off_t got_file_offset = this->got_plt_->offset();
4139 const section_size_type got_size =
4140 convert_to_section_size_type(this->got_plt_->data_size());
4141 unsigned char* const got_view = of->get_output_view(got_file_offset,
4143 unsigned char* pov = oview;
4145 Arm_address plt_address = this->address();
4146 Arm_address got_address = this->got_plt_->address();
4148 // Write first PLT entry. All but the last word are constants.
4149 const size_t num_first_plt_words = (sizeof(first_plt_entry)
4150 / sizeof(plt_entry[0]));
4151 for (size_t i = 0; i < num_first_plt_words - 1; i++)
4152 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
4153 // Last word in first PLT entry is &GOT[0] - .
4154 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
4155 got_address - (plt_address + 16));
4156 pov += sizeof(first_plt_entry);
4158 unsigned char* got_pov = got_view;
4160 memset(got_pov, 0, 12);
4163 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
4164 unsigned int plt_offset = sizeof(first_plt_entry);
4165 unsigned int plt_rel_offset = 0;
4166 unsigned int got_offset = 12;
4167 const unsigned int count = this->count_;
4168 for (unsigned int i = 0;
4171 pov += sizeof(plt_entry),
4173 plt_offset += sizeof(plt_entry),
4174 plt_rel_offset += rel_size,
4177 // Set and adjust the PLT entry itself.
4178 int32_t offset = ((got_address + got_offset)
4179 - (plt_address + plt_offset + 8));
4181 gold_assert(offset >= 0 && offset < 0x0fffffff);
4182 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
4183 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
4184 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
4185 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
4186 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
4187 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
4189 // Set the entry in the GOT.
4190 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
4193 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
4194 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
4196 of->write_output_view(offset, oview_size, oview);
4197 of->write_output_view(got_file_offset, got_size, got_view);
4200 // Create a PLT entry for a global symbol.
4202 template<bool big_endian>
4204 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
4207 if (gsym->has_plt_offset())
4210 if (this->plt_ == NULL)
4212 // Create the GOT sections first.
4213 this->got_section(symtab, layout);
4215 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
4216 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
4218 | elfcpp::SHF_EXECINSTR),
4219 this->plt_, false, false, false, false);
4221 this->plt_->add_entry(gsym);
4224 // Report an unsupported relocation against a local symbol.
4226 template<bool big_endian>
4228 Target_arm<big_endian>::Scan::unsupported_reloc_local(
4229 Sized_relobj<32, big_endian>* object,
4230 unsigned int r_type)
4232 gold_error(_("%s: unsupported reloc %u against local symbol"),
4233 object->name().c_str(), r_type);
4236 // We are about to emit a dynamic relocation of type R_TYPE. If the
4237 // dynamic linker does not support it, issue an error. The GNU linker
4238 // only issues a non-PIC error for an allocated read-only section.
4239 // Here we know the section is allocated, but we don't know that it is
4240 // read-only. But we check for all the relocation types which the
4241 // glibc dynamic linker supports, so it seems appropriate to issue an
4242 // error even if the section is not read-only.
4244 template<bool big_endian>
4246 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
4247 unsigned int r_type)
4251 // These are the relocation types supported by glibc for ARM.
4252 case elfcpp::R_ARM_RELATIVE:
4253 case elfcpp::R_ARM_COPY:
4254 case elfcpp::R_ARM_GLOB_DAT:
4255 case elfcpp::R_ARM_JUMP_SLOT:
4256 case elfcpp::R_ARM_ABS32:
4257 case elfcpp::R_ARM_ABS32_NOI:
4258 case elfcpp::R_ARM_PC24:
4259 // FIXME: The following 3 types are not supported by Android's dynamic
4261 case elfcpp::R_ARM_TLS_DTPMOD32:
4262 case elfcpp::R_ARM_TLS_DTPOFF32:
4263 case elfcpp::R_ARM_TLS_TPOFF32:
4267 // This prevents us from issuing more than one error per reloc
4268 // section. But we can still wind up issuing more than one
4269 // error per object file.
4270 if (this->issued_non_pic_error_)
4272 object->error(_("requires unsupported dynamic reloc; "
4273 "recompile with -fPIC"));
4274 this->issued_non_pic_error_ = true;
4277 case elfcpp::R_ARM_NONE:
4282 // Scan a relocation for a local symbol.
4283 // FIXME: This only handles a subset of relocation types used by Android
4284 // on ARM v5te devices.
4286 template<bool big_endian>
4288 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
4291 Sized_relobj<32, big_endian>* object,
4292 unsigned int data_shndx,
4293 Output_section* output_section,
4294 const elfcpp::Rel<32, big_endian>& reloc,
4295 unsigned int r_type,
4296 const elfcpp::Sym<32, big_endian>&)
4298 r_type = get_real_reloc_type(r_type);
4301 case elfcpp::R_ARM_NONE:
4304 case elfcpp::R_ARM_ABS32:
4305 case elfcpp::R_ARM_ABS32_NOI:
4306 // If building a shared library (or a position-independent
4307 // executable), we need to create a dynamic relocation for
4308 // this location. The relocation applied at link time will
4309 // apply the link-time value, so we flag the location with
4310 // an R_ARM_RELATIVE relocation so the dynamic loader can
4311 // relocate it easily.
4312 if (parameters->options().output_is_position_independent())
4314 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4315 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
4316 // If we are to add more other reloc types than R_ARM_ABS32,
4317 // we need to add check_non_pic(object, r_type) here.
4318 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
4319 output_section, data_shndx,
4320 reloc.get_r_offset());
4324 case elfcpp::R_ARM_REL32:
4325 case elfcpp::R_ARM_THM_CALL:
4326 case elfcpp::R_ARM_CALL:
4327 case elfcpp::R_ARM_PREL31:
4328 case elfcpp::R_ARM_JUMP24:
4329 case elfcpp::R_ARM_PLT32:
4330 case elfcpp::R_ARM_THM_ABS5:
4331 case elfcpp::R_ARM_ABS8:
4332 case elfcpp::R_ARM_ABS12:
4333 case elfcpp::R_ARM_ABS16:
4334 case elfcpp::R_ARM_BASE_ABS:
4335 case elfcpp::R_ARM_MOVW_ABS_NC:
4336 case elfcpp::R_ARM_MOVT_ABS:
4337 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
4338 case elfcpp::R_ARM_THM_MOVT_ABS:
4339 case elfcpp::R_ARM_MOVW_PREL_NC:
4340 case elfcpp::R_ARM_MOVT_PREL:
4341 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
4342 case elfcpp::R_ARM_THM_MOVT_PREL:
4345 case elfcpp::R_ARM_GOTOFF32:
4346 // We need a GOT section:
4347 target->got_section(symtab, layout);
4350 case elfcpp::R_ARM_BASE_PREL:
4351 // FIXME: What about this?
4354 case elfcpp::R_ARM_GOT_BREL:
4355 case elfcpp::R_ARM_GOT_PREL:
4357 // The symbol requires a GOT entry.
4358 Output_data_got<32, big_endian>* got =
4359 target->got_section(symtab, layout);
4360 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
4361 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
4363 // If we are generating a shared object, we need to add a
4364 // dynamic RELATIVE relocation for this symbol's GOT entry.
4365 if (parameters->options().output_is_position_independent())
4367 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4368 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
4369 rel_dyn->add_local_relative(
4370 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
4371 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
4377 case elfcpp::R_ARM_TARGET1:
4378 // This should have been mapped to another type already.
4380 case elfcpp::R_ARM_COPY:
4381 case elfcpp::R_ARM_GLOB_DAT:
4382 case elfcpp::R_ARM_JUMP_SLOT:
4383 case elfcpp::R_ARM_RELATIVE:
4384 // These are relocations which should only be seen by the
4385 // dynamic linker, and should never be seen here.
4386 gold_error(_("%s: unexpected reloc %u in object file"),
4387 object->name().c_str(), r_type);
4391 unsupported_reloc_local(object, r_type);
4396 // Report an unsupported relocation against a global symbol.
4398 template<bool big_endian>
4400 Target_arm<big_endian>::Scan::unsupported_reloc_global(
4401 Sized_relobj<32, big_endian>* object,
4402 unsigned int r_type,
4405 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
4406 object->name().c_str(), r_type, gsym->demangled_name().c_str());
4409 // Scan a relocation for a global symbol.
4410 // FIXME: This only handles a subset of relocation types used by Android
4411 // on ARM v5te devices.
4413 template<bool big_endian>
4415 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
4418 Sized_relobj<32, big_endian>* object,
4419 unsigned int data_shndx,
4420 Output_section* output_section,
4421 const elfcpp::Rel<32, big_endian>& reloc,
4422 unsigned int r_type,
4425 r_type = get_real_reloc_type(r_type);
4428 case elfcpp::R_ARM_NONE:
4431 case elfcpp::R_ARM_ABS32:
4432 case elfcpp::R_ARM_ABS32_NOI:
4434 // Make a dynamic relocation if necessary.
4435 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
4437 if (target->may_need_copy_reloc(gsym))
4439 target->copy_reloc(symtab, layout, object,
4440 data_shndx, output_section, gsym, reloc);
4442 else if (gsym->can_use_relative_reloc(false))
4444 // If we are to add more other reloc types than R_ARM_ABS32,
4445 // we need to add check_non_pic(object, r_type) here.
4446 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4447 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
4448 output_section, object,
4449 data_shndx, reloc.get_r_offset());
4453 // If we are to add more other reloc types than R_ARM_ABS32,
4454 // we need to add check_non_pic(object, r_type) here.
4455 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4456 rel_dyn->add_global(gsym, r_type, output_section, object,
4457 data_shndx, reloc.get_r_offset());
4463 case elfcpp::R_ARM_MOVW_ABS_NC:
4464 case elfcpp::R_ARM_MOVT_ABS:
4465 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
4466 case elfcpp::R_ARM_THM_MOVT_ABS:
4467 case elfcpp::R_ARM_MOVW_PREL_NC:
4468 case elfcpp::R_ARM_MOVT_PREL:
4469 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
4470 case elfcpp::R_ARM_THM_MOVT_PREL:
4473 case elfcpp::R_ARM_THM_ABS5:
4474 case elfcpp::R_ARM_ABS8:
4475 case elfcpp::R_ARM_ABS12:
4476 case elfcpp::R_ARM_ABS16:
4477 case elfcpp::R_ARM_BASE_ABS:
4479 // No dynamic relocs of this kinds.
4480 // Report the error in case of PIC.
4481 int flags = Symbol::NON_PIC_REF;
4482 if (gsym->type() == elfcpp::STT_FUNC
4483 || gsym->type() == elfcpp::STT_ARM_TFUNC)
4484 flags |= Symbol::FUNCTION_CALL;
4485 if (gsym->needs_dynamic_reloc(flags))
4486 check_non_pic(object, r_type);
4490 case elfcpp::R_ARM_REL32:
4491 case elfcpp::R_ARM_PREL31:
4493 // Make a dynamic relocation if necessary.
4494 int flags = Symbol::NON_PIC_REF;
4495 if (gsym->needs_dynamic_reloc(flags))
4497 if (target->may_need_copy_reloc(gsym))
4499 target->copy_reloc(symtab, layout, object,
4500 data_shndx, output_section, gsym, reloc);
4504 check_non_pic(object, r_type);
4505 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4506 rel_dyn->add_global(gsym, r_type, output_section, object,
4507 data_shndx, reloc.get_r_offset());
4513 case elfcpp::R_ARM_JUMP24:
4514 case elfcpp::R_ARM_THM_JUMP24:
4515 case elfcpp::R_ARM_CALL:
4516 case elfcpp::R_ARM_THM_CALL:
4518 if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym))
4519 target->make_plt_entry(symtab, layout, gsym);
4522 // Check to see if this is a function that would need a PLT
4523 // but does not get one because the function symbol is untyped.
4524 // This happens in assembly code missing a proper .type directive.
4525 if ((!gsym->is_undefined() || parameters->options().shared())
4526 && !parameters->doing_static_link()
4527 && gsym->type() == elfcpp::STT_NOTYPE
4528 && (gsym->is_from_dynobj()
4529 || gsym->is_undefined()
4530 || gsym->is_preemptible()))
4531 gold_error(_("%s is not a function."),
4532 gsym->demangled_name().c_str());
4536 case elfcpp::R_ARM_PLT32:
4537 // If the symbol is fully resolved, this is just a relative
4538 // local reloc. Otherwise we need a PLT entry.
4539 if (gsym->final_value_is_known())
4541 // If building a shared library, we can also skip the PLT entry
4542 // if the symbol is defined in the output file and is protected
4544 if (gsym->is_defined()
4545 && !gsym->is_from_dynobj()
4546 && !gsym->is_preemptible())
4548 target->make_plt_entry(symtab, layout, gsym);
4551 case elfcpp::R_ARM_GOTOFF32:
4552 // We need a GOT section.
4553 target->got_section(symtab, layout);
4556 case elfcpp::R_ARM_BASE_PREL:
4557 // FIXME: What about this?
4560 case elfcpp::R_ARM_GOT_BREL:
4561 case elfcpp::R_ARM_GOT_PREL:
4563 // The symbol requires a GOT entry.
4564 Output_data_got<32, big_endian>* got =
4565 target->got_section(symtab, layout);
4566 if (gsym->final_value_is_known())
4567 got->add_global(gsym, GOT_TYPE_STANDARD);
4570 // If this symbol is not fully resolved, we need to add a
4571 // GOT entry with a dynamic relocation.
4572 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4573 if (gsym->is_from_dynobj()
4574 || gsym->is_undefined()
4575 || gsym->is_preemptible())
4576 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
4577 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
4580 if (got->add_global(gsym, GOT_TYPE_STANDARD))
4581 rel_dyn->add_global_relative(
4582 gsym, elfcpp::R_ARM_RELATIVE, got,
4583 gsym->got_offset(GOT_TYPE_STANDARD));
4589 case elfcpp::R_ARM_TARGET1:
4590 // This should have been mapped to another type already.
4592 case elfcpp::R_ARM_COPY:
4593 case elfcpp::R_ARM_GLOB_DAT:
4594 case elfcpp::R_ARM_JUMP_SLOT:
4595 case elfcpp::R_ARM_RELATIVE:
4596 // These are relocations which should only be seen by the
4597 // dynamic linker, and should never be seen here.
4598 gold_error(_("%s: unexpected reloc %u in object file"),
4599 object->name().c_str(), r_type);
4603 unsupported_reloc_global(object, r_type, gsym);
4608 // Process relocations for gc.
4610 template<bool big_endian>
4612 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
4614 Sized_relobj<32, big_endian>* object,
4615 unsigned int data_shndx,
4617 const unsigned char* prelocs,
4619 Output_section* output_section,
4620 bool needs_special_offset_handling,
4621 size_t local_symbol_count,
4622 const unsigned char* plocal_symbols)
4624 typedef Target_arm<big_endian> Arm;
4625 typedef typename Target_arm<big_endian>::Scan Scan;
4627 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
4636 needs_special_offset_handling,
4641 // Scan relocations for a section.
4643 template<bool big_endian>
4645 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
4647 Sized_relobj<32, big_endian>* object,
4648 unsigned int data_shndx,
4649 unsigned int sh_type,
4650 const unsigned char* prelocs,
4652 Output_section* output_section,
4653 bool needs_special_offset_handling,
4654 size_t local_symbol_count,
4655 const unsigned char* plocal_symbols)
4657 typedef typename Target_arm<big_endian>::Scan Scan;
4658 if (sh_type == elfcpp::SHT_RELA)
4660 gold_error(_("%s: unsupported RELA reloc section"),
4661 object->name().c_str());
4665 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
4674 needs_special_offset_handling,
4679 // Finalize the sections.
4681 template<bool big_endian>
4683 Target_arm<big_endian>::do_finalize_sections(
4685 const Input_objects* input_objects,
4686 Symbol_table* symtab)
4688 // Merge processor-specific flags.
4689 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
4690 p != input_objects->relobj_end();
4693 Arm_relobj<big_endian>* arm_relobj =
4694 Arm_relobj<big_endian>::as_arm_relobj(*p);
4695 this->merge_processor_specific_flags(
4697 arm_relobj->processor_specific_flags());
4698 this->merge_object_attributes(arm_relobj->name().c_str(),
4699 arm_relobj->attributes_section_data());
4703 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
4704 p != input_objects->dynobj_end();
4707 Arm_dynobj<big_endian>* arm_dynobj =
4708 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
4709 this->merge_processor_specific_flags(
4711 arm_dynobj->processor_specific_flags());
4712 this->merge_object_attributes(arm_dynobj->name().c_str(),
4713 arm_dynobj->attributes_section_data());
4717 Object_attribute* attr =
4718 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
4719 if (attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
4720 this->set_may_use_blx(true);
4722 // Fill in some more dynamic tags.
4723 Output_data_dynamic* const odyn = layout->dynamic_data();
4726 if (this->got_plt_ != NULL
4727 && this->got_plt_->output_section() != NULL)
4728 odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
4730 if (this->plt_ != NULL
4731 && this->plt_->output_section() != NULL)
4733 const Output_data* od = this->plt_->rel_plt();
4734 odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
4735 odyn->add_section_address(elfcpp::DT_JMPREL, od);
4736 odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
4739 if (this->rel_dyn_ != NULL
4740 && this->rel_dyn_->output_section() != NULL)
4742 const Output_data* od = this->rel_dyn_;
4743 odyn->add_section_address(elfcpp::DT_REL, od);
4744 odyn->add_section_size(elfcpp::DT_RELSZ, od);
4745 odyn->add_constant(elfcpp::DT_RELENT,
4746 elfcpp::Elf_sizes<32>::rel_size);
4749 if (!parameters->options().shared())
4751 // The value of the DT_DEBUG tag is filled in by the dynamic
4752 // linker at run time, and used by the debugger.
4753 odyn->add_constant(elfcpp::DT_DEBUG, 0);
4757 // Emit any relocs we saved in an attempt to avoid generating COPY
4759 if (this->copy_relocs_.any_saved_relocs())
4760 this->copy_relocs_.emit(this->rel_dyn_section(layout));
4762 // Handle the .ARM.exidx section.
4763 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
4764 if (exidx_section != NULL
4765 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
4766 && !parameters->options().relocatable())
4768 // Create __exidx_start and __exdix_end symbols.
4769 symtab->define_in_output_data("__exidx_start", NULL,
4770 Symbol_table::PREDEFINED,
4771 exidx_section, 0, 0, elfcpp::STT_OBJECT,
4772 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
4774 symtab->define_in_output_data("__exidx_end", NULL,
4775 Symbol_table::PREDEFINED,
4776 exidx_section, 0, 0, elfcpp::STT_OBJECT,
4777 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
4780 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
4781 // the .ARM.exidx section.
4782 if (!layout->script_options()->saw_phdrs_clause())
4784 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
4786 Output_segment* exidx_segment =
4787 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
4788 exidx_segment->add_output_section(exidx_section, elfcpp::PF_R,
4793 // Create an .ARM.attributes section if there is not one already.
4794 Output_attributes_section_data* attributes_section =
4795 new Output_attributes_section_data(*this->attributes_section_data_);
4796 layout->add_output_section_data(".ARM.attributes",
4797 elfcpp::SHT_ARM_ATTRIBUTES, 0,
4798 attributes_section, false, false, false,
4802 // Return whether a direct absolute static relocation needs to be applied.
4803 // In cases where Scan::local() or Scan::global() has created
4804 // a dynamic relocation other than R_ARM_RELATIVE, the addend
4805 // of the relocation is carried in the data, and we must not
4806 // apply the static relocation.
4808 template<bool big_endian>
4810 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
4811 const Sized_symbol<32>* gsym,
4814 Output_section* output_section)
4816 // If the output section is not allocated, then we didn't call
4817 // scan_relocs, we didn't create a dynamic reloc, and we must apply
4819 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
4822 // For local symbols, we will have created a non-RELATIVE dynamic
4823 // relocation only if (a) the output is position independent,
4824 // (b) the relocation is absolute (not pc- or segment-relative), and
4825 // (c) the relocation is not 32 bits wide.
4827 return !(parameters->options().output_is_position_independent()
4828 && (ref_flags & Symbol::ABSOLUTE_REF)
4831 // For global symbols, we use the same helper routines used in the
4832 // scan pass. If we did not create a dynamic relocation, or if we
4833 // created a RELATIVE dynamic relocation, we should apply the static
4835 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
4836 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
4837 && gsym->can_use_relative_reloc(ref_flags
4838 & Symbol::FUNCTION_CALL);
4839 return !has_dyn || is_rel;
4842 // Perform a relocation.
4844 template<bool big_endian>
4846 Target_arm<big_endian>::Relocate::relocate(
4847 const Relocate_info<32, big_endian>* relinfo,
4849 Output_section *output_section,
4851 const elfcpp::Rel<32, big_endian>& rel,
4852 unsigned int r_type,
4853 const Sized_symbol<32>* gsym,
4854 const Symbol_value<32>* psymval,
4855 unsigned char* view,
4856 Arm_address address,
4857 section_size_type /* view_size */ )
4859 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
4861 r_type = get_real_reloc_type(r_type);
4863 const Arm_relobj<big_endian>* object =
4864 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
4866 // If the final branch target of a relocation is THUMB instruction, this
4867 // is 1. Otherwise it is 0.
4868 Arm_address thumb_bit = 0;
4869 Symbol_value<32> symval;
4870 bool is_weakly_undefined_without_plt = false;
4871 if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
4875 // This is a global symbol. Determine if we use PLT and if the
4876 // final target is THUMB.
4877 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
4879 // This uses a PLT, change the symbol value.
4880 symval.set_output_value(target->plt_section()->address()
4881 + gsym->plt_offset());
4884 else if (gsym->is_weak_undefined())
4886 // This is a weakly undefined symbol and we do not use PLT
4887 // for this relocation. A branch targeting this symbol will
4888 // be converted into an NOP.
4889 is_weakly_undefined_without_plt = true;
4893 // Set thumb bit if symbol:
4894 // -Has type STT_ARM_TFUNC or
4895 // -Has type STT_FUNC, is defined and with LSB in value set.
4897 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
4898 || (gsym->type() == elfcpp::STT_FUNC
4899 && !gsym->is_undefined()
4900 && ((psymval->value(object, 0) & 1) != 0)))
4907 // This is a local symbol. Determine if the final target is THUMB.
4908 // We saved this information when all the local symbols were read.
4909 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
4910 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
4911 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
4916 // This is a fake relocation synthesized for a stub. It does not have
4917 // a real symbol. We just look at the LSB of the symbol value to
4918 // determine if the target is THUMB or not.
4919 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
4922 // Strip LSB if this points to a THUMB target.
4924 && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type)
4925 && ((psymval->value(object, 0) & 1) != 0))
4927 Arm_address stripped_value =
4928 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
4929 symval.set_output_value(stripped_value);
4933 // Get the GOT offset if needed.
4934 // The GOT pointer points to the end of the GOT section.
4935 // We need to subtract the size of the GOT section to get
4936 // the actual offset to use in the relocation.
4937 bool have_got_offset = false;
4938 unsigned int got_offset = 0;
4941 case elfcpp::R_ARM_GOT_BREL:
4942 case elfcpp::R_ARM_GOT_PREL:
4945 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
4946 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
4947 - target->got_size());
4951 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
4952 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
4953 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
4954 - target->got_size());
4956 have_got_offset = true;
4963 // To look up relocation stubs, we need to pass the symbol table index of
4965 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
4967 typename Arm_relocate_functions::Status reloc_status =
4968 Arm_relocate_functions::STATUS_OKAY;
4971 case elfcpp::R_ARM_NONE:
4974 case elfcpp::R_ARM_ABS8:
4975 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
4977 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
4980 case elfcpp::R_ARM_ABS12:
4981 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
4983 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
4986 case elfcpp::R_ARM_ABS16:
4987 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
4989 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
4992 case elfcpp::R_ARM_ABS32:
4993 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
4995 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
4999 case elfcpp::R_ARM_ABS32_NOI:
5000 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5002 // No thumb bit for this relocation: (S + A)
5003 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
5007 case elfcpp::R_ARM_MOVW_ABS_NC:
5008 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5010 reloc_status = Arm_relocate_functions::movw_abs_nc(view, object,
5014 gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making"
5015 "a shared object; recompile with -fPIC"));
5018 case elfcpp::R_ARM_MOVT_ABS:
5019 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5021 reloc_status = Arm_relocate_functions::movt_abs(view, object, psymval);
5023 gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making"
5024 "a shared object; recompile with -fPIC"));
5027 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
5028 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5030 reloc_status = Arm_relocate_functions::thm_movw_abs_nc(view, object,
5034 gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when"
5035 "making a shared object; recompile with -fPIC"));
5038 case elfcpp::R_ARM_THM_MOVT_ABS:
5039 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5041 reloc_status = Arm_relocate_functions::thm_movt_abs(view, object,
5044 gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when"
5045 "making a shared object; recompile with -fPIC"));
5048 case elfcpp::R_ARM_MOVW_PREL_NC:
5049 reloc_status = Arm_relocate_functions::movw_prel_nc(view, object,
5054 case elfcpp::R_ARM_MOVT_PREL:
5055 reloc_status = Arm_relocate_functions::movt_prel(view, object,
5059 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
5060 reloc_status = Arm_relocate_functions::thm_movw_prel_nc(view, object,
5065 case elfcpp::R_ARM_THM_MOVT_PREL:
5066 reloc_status = Arm_relocate_functions::thm_movt_prel(view, object,
5070 case elfcpp::R_ARM_REL32:
5071 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
5072 address, thumb_bit);
5075 case elfcpp::R_ARM_THM_ABS5:
5076 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
5078 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
5081 case elfcpp::R_ARM_THM_CALL:
5083 Arm_relocate_functions::thm_call(relinfo, view, gsym, object, r_sym,
5084 psymval, address, thumb_bit,
5085 is_weakly_undefined_without_plt);
5088 case elfcpp::R_ARM_XPC25:
5090 Arm_relocate_functions::xpc25(relinfo, view, gsym, object, r_sym,
5091 psymval, address, thumb_bit,
5092 is_weakly_undefined_without_plt);
5095 case elfcpp::R_ARM_THM_XPC22:
5097 Arm_relocate_functions::thm_xpc22(relinfo, view, gsym, object, r_sym,
5098 psymval, address, thumb_bit,
5099 is_weakly_undefined_without_plt);
5102 case elfcpp::R_ARM_GOTOFF32:
5104 Arm_address got_origin;
5105 got_origin = target->got_plt_section()->address();
5106 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
5107 got_origin, thumb_bit);
5111 case elfcpp::R_ARM_BASE_PREL:
5114 // Get the addressing origin of the output segment defining the
5115 // symbol gsym (AAELF 4.6.1.2 Relocation types)
5116 gold_assert(gsym != NULL);
5117 if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
5118 origin = gsym->output_segment()->vaddr();
5119 else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
5120 origin = gsym->output_data()->address();
5123 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
5124 _("cannot find origin of R_ARM_BASE_PREL"));
5127 reloc_status = Arm_relocate_functions::base_prel(view, origin, address);
5131 case elfcpp::R_ARM_BASE_ABS:
5133 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
5138 // Get the addressing origin of the output segment defining
5139 // the symbol gsym (AAELF 4.6.1.2 Relocation types).
5141 // R_ARM_BASE_ABS with the NULL symbol will give the
5142 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
5143 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
5144 origin = target->got_plt_section()->address();
5145 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
5146 origin = gsym->output_segment()->vaddr();
5147 else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
5148 origin = gsym->output_data()->address();
5151 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
5152 _("cannot find origin of R_ARM_BASE_ABS"));
5156 reloc_status = Arm_relocate_functions::base_abs(view, origin);
5160 case elfcpp::R_ARM_GOT_BREL:
5161 gold_assert(have_got_offset);
5162 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
5165 case elfcpp::R_ARM_GOT_PREL:
5166 gold_assert(have_got_offset);
5167 // Get the address origin for GOT PLT, which is allocated right
5168 // after the GOT section, to calculate an absolute address of
5169 // the symbol GOT entry (got_origin + got_offset).
5170 Arm_address got_origin;
5171 got_origin = target->got_plt_section()->address();
5172 reloc_status = Arm_relocate_functions::got_prel(view,
5173 got_origin + got_offset,
5177 case elfcpp::R_ARM_PLT32:
5178 gold_assert(gsym == NULL
5179 || gsym->has_plt_offset()
5180 || gsym->final_value_is_known()
5181 || (gsym->is_defined()
5182 && !gsym->is_from_dynobj()
5183 && !gsym->is_preemptible()));
5185 Arm_relocate_functions::plt32(relinfo, view, gsym, object, r_sym,
5186 psymval, address, thumb_bit,
5187 is_weakly_undefined_without_plt);
5190 case elfcpp::R_ARM_CALL:
5192 Arm_relocate_functions::call(relinfo, view, gsym, object, r_sym,
5193 psymval, address, thumb_bit,
5194 is_weakly_undefined_without_plt);
5197 case elfcpp::R_ARM_JUMP24:
5199 Arm_relocate_functions::jump24(relinfo, view, gsym, object, r_sym,
5200 psymval, address, thumb_bit,
5201 is_weakly_undefined_without_plt);
5204 case elfcpp::R_ARM_THM_JUMP24:
5206 Arm_relocate_functions::thm_jump24(relinfo, view, gsym, object, r_sym,
5207 psymval, address, thumb_bit,
5208 is_weakly_undefined_without_plt);
5211 case elfcpp::R_ARM_PREL31:
5212 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
5213 address, thumb_bit);
5216 case elfcpp::R_ARM_TARGET1:
5217 // This should have been mapped to another type already.
5219 case elfcpp::R_ARM_COPY:
5220 case elfcpp::R_ARM_GLOB_DAT:
5221 case elfcpp::R_ARM_JUMP_SLOT:
5222 case elfcpp::R_ARM_RELATIVE:
5223 // These are relocations which should only be seen by the
5224 // dynamic linker, and should never be seen here.
5225 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
5226 _("unexpected reloc %u in object file"),
5231 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
5232 _("unsupported reloc %u"),
5237 // Report any errors.
5238 switch (reloc_status)
5240 case Arm_relocate_functions::STATUS_OKAY:
5242 case Arm_relocate_functions::STATUS_OVERFLOW:
5243 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
5244 _("relocation overflow in relocation %u"),
5247 case Arm_relocate_functions::STATUS_BAD_RELOC:
5248 gold_error_at_location(
5252 _("unexpected opcode while processing relocation %u"),
5262 // Relocate section data.
5264 template<bool big_endian>
5266 Target_arm<big_endian>::relocate_section(
5267 const Relocate_info<32, big_endian>* relinfo,
5268 unsigned int sh_type,
5269 const unsigned char* prelocs,
5271 Output_section* output_section,
5272 bool needs_special_offset_handling,
5273 unsigned char* view,
5274 Arm_address address,
5275 section_size_type view_size,
5276 const Reloc_symbol_changes* reloc_symbol_changes)
5278 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
5279 gold_assert(sh_type == elfcpp::SHT_REL);
5281 Arm_input_section<big_endian>* arm_input_section =
5282 this->find_arm_input_section(relinfo->object, relinfo->data_shndx);
5284 // This is an ARM input section and the view covers the whole output
5286 if (arm_input_section != NULL)
5288 gold_assert(needs_special_offset_handling);
5289 Arm_address section_address = arm_input_section->address();
5290 section_size_type section_size = arm_input_section->data_size();
5292 gold_assert((arm_input_section->address() >= address)
5293 && ((arm_input_section->address()
5294 + arm_input_section->data_size())
5295 <= (address + view_size)));
5297 off_t offset = section_address - address;
5300 view_size = section_size;
5303 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
5310 needs_special_offset_handling,
5314 reloc_symbol_changes);
5317 // Return the size of a relocation while scanning during a relocatable
5320 template<bool big_endian>
5322 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
5323 unsigned int r_type,
5326 r_type = get_real_reloc_type(r_type);
5329 case elfcpp::R_ARM_NONE:
5332 case elfcpp::R_ARM_ABS8:
5335 case elfcpp::R_ARM_ABS16:
5336 case elfcpp::R_ARM_THM_ABS5:
5339 case elfcpp::R_ARM_ABS32:
5340 case elfcpp::R_ARM_ABS32_NOI:
5341 case elfcpp::R_ARM_ABS12:
5342 case elfcpp::R_ARM_BASE_ABS:
5343 case elfcpp::R_ARM_REL32:
5344 case elfcpp::R_ARM_THM_CALL:
5345 case elfcpp::R_ARM_GOTOFF32:
5346 case elfcpp::R_ARM_BASE_PREL:
5347 case elfcpp::R_ARM_GOT_BREL:
5348 case elfcpp::R_ARM_GOT_PREL:
5349 case elfcpp::R_ARM_PLT32:
5350 case elfcpp::R_ARM_CALL:
5351 case elfcpp::R_ARM_JUMP24:
5352 case elfcpp::R_ARM_PREL31:
5353 case elfcpp::R_ARM_MOVW_ABS_NC:
5354 case elfcpp::R_ARM_MOVT_ABS:
5355 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
5356 case elfcpp::R_ARM_THM_MOVT_ABS:
5357 case elfcpp::R_ARM_MOVW_PREL_NC:
5358 case elfcpp::R_ARM_MOVT_PREL:
5359 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
5360 case elfcpp::R_ARM_THM_MOVT_PREL:
5363 case elfcpp::R_ARM_TARGET1:
5364 // This should have been mapped to another type already.
5366 case elfcpp::R_ARM_COPY:
5367 case elfcpp::R_ARM_GLOB_DAT:
5368 case elfcpp::R_ARM_JUMP_SLOT:
5369 case elfcpp::R_ARM_RELATIVE:
5370 // These are relocations which should only be seen by the
5371 // dynamic linker, and should never be seen here.
5372 gold_error(_("%s: unexpected reloc %u in object file"),
5373 object->name().c_str(), r_type);
5377 object->error(_("unsupported reloc %u in object file"), r_type);
5382 // Scan the relocs during a relocatable link.
5384 template<bool big_endian>
5386 Target_arm<big_endian>::scan_relocatable_relocs(
5387 Symbol_table* symtab,
5389 Sized_relobj<32, big_endian>* object,
5390 unsigned int data_shndx,
5391 unsigned int sh_type,
5392 const unsigned char* prelocs,
5394 Output_section* output_section,
5395 bool needs_special_offset_handling,
5396 size_t local_symbol_count,
5397 const unsigned char* plocal_symbols,
5398 Relocatable_relocs* rr)
5400 gold_assert(sh_type == elfcpp::SHT_REL);
5402 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
5403 Relocatable_size_for_reloc> Scan_relocatable_relocs;
5405 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
5406 Scan_relocatable_relocs>(
5414 needs_special_offset_handling,
5420 // Relocate a section during a relocatable link.
5422 template<bool big_endian>
5424 Target_arm<big_endian>::relocate_for_relocatable(
5425 const Relocate_info<32, big_endian>* relinfo,
5426 unsigned int sh_type,
5427 const unsigned char* prelocs,
5429 Output_section* output_section,
5430 off_t offset_in_output_section,
5431 const Relocatable_relocs* rr,
5432 unsigned char* view,
5433 Arm_address view_address,
5434 section_size_type view_size,
5435 unsigned char* reloc_view,
5436 section_size_type reloc_view_size)
5438 gold_assert(sh_type == elfcpp::SHT_REL);
5440 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
5445 offset_in_output_section,
5454 // Return the value to use for a dynamic symbol which requires special
5455 // treatment. This is how we support equality comparisons of function
5456 // pointers across shared library boundaries, as described in the
5457 // processor specific ABI supplement.
5459 template<bool big_endian>
5461 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
5463 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
5464 return this->plt_section()->address() + gsym->plt_offset();
5467 // Map platform-specific relocs to real relocs
5469 template<bool big_endian>
5471 Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
5475 case elfcpp::R_ARM_TARGET1:
5476 // This is either R_ARM_ABS32 or R_ARM_REL32;
5477 return elfcpp::R_ARM_ABS32;
5479 case elfcpp::R_ARM_TARGET2:
5480 // This can be any reloc type but ususally is R_ARM_GOT_PREL
5481 return elfcpp::R_ARM_GOT_PREL;
5488 // Whether if two EABI versions V1 and V2 are compatible.
5490 template<bool big_endian>
5492 Target_arm<big_endian>::are_eabi_versions_compatible(
5493 elfcpp::Elf_Word v1,
5494 elfcpp::Elf_Word v2)
5496 // v4 and v5 are the same spec before and after it was released,
5497 // so allow mixing them.
5498 if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
5499 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
5505 // Combine FLAGS from an input object called NAME and the processor-specific
5506 // flags in the ELF header of the output. Much of this is adapted from the
5507 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
5508 // in bfd/elf32-arm.c.
5510 template<bool big_endian>
5512 Target_arm<big_endian>::merge_processor_specific_flags(
5513 const std::string& name,
5514 elfcpp::Elf_Word flags)
5516 if (this->are_processor_specific_flags_set())
5518 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
5520 // Nothing to merge if flags equal to those in output.
5521 if (flags == out_flags)
5524 // Complain about various flag mismatches.
5525 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
5526 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
5527 if (!this->are_eabi_versions_compatible(version1, version2))
5528 gold_error(_("Source object %s has EABI version %d but output has "
5529 "EABI version %d."),
5531 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
5532 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
5536 // If the input is the default architecture and had the default
5537 // flags then do not bother setting the flags for the output
5538 // architecture, instead allow future merges to do this. If no
5539 // future merges ever set these flags then they will retain their
5540 // uninitialised values, which surprise surprise, correspond
5541 // to the default values.
5545 // This is the first time, just copy the flags.
5546 // We only copy the EABI version for now.
5547 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
5551 // Adjust ELF file header.
5552 template<bool big_endian>
5554 Target_arm<big_endian>::do_adjust_elf_header(
5555 unsigned char* view,
5558 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
5560 elfcpp::Ehdr<32, big_endian> ehdr(view);
5561 unsigned char e_ident[elfcpp::EI_NIDENT];
5562 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
5564 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
5565 == elfcpp::EF_ARM_EABI_UNKNOWN)
5566 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
5568 e_ident[elfcpp::EI_OSABI] = 0;
5569 e_ident[elfcpp::EI_ABIVERSION] = 0;
5571 // FIXME: Do EF_ARM_BE8 adjustment.
5573 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
5574 oehdr.put_e_ident(e_ident);
5577 // do_make_elf_object to override the same function in the base class.
5578 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
5579 // to store ARM specific information. Hence we need to have our own
5580 // ELF object creation.
5582 template<bool big_endian>
5584 Target_arm<big_endian>::do_make_elf_object(
5585 const std::string& name,
5586 Input_file* input_file,
5587 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
5589 int et = ehdr.get_e_type();
5590 if (et == elfcpp::ET_REL)
5592 Arm_relobj<big_endian>* obj =
5593 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
5597 else if (et == elfcpp::ET_DYN)
5599 Sized_dynobj<32, big_endian>* obj =
5600 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
5606 gold_error(_("%s: unsupported ELF file type %d"),
5612 // Read the architecture from the Tag_also_compatible_with attribute, if any.
5613 // Returns -1 if no architecture could be read.
5614 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
5616 template<bool big_endian>
5618 Target_arm<big_endian>::get_secondary_compatible_arch(
5619 const Attributes_section_data* pasd)
5621 const Object_attribute *known_attributes =
5622 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
5624 // Note: the tag and its argument below are uleb128 values, though
5625 // currently-defined values fit in one byte for each.
5626 const std::string& sv =
5627 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
5629 && sv.data()[0] == elfcpp::Tag_CPU_arch
5630 && (sv.data()[1] & 128) != 128)
5631 return sv.data()[1];
5633 // This tag is "safely ignorable", so don't complain if it looks funny.
5637 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
5638 // The tag is removed if ARCH is -1.
5639 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
5641 template<bool big_endian>
5643 Target_arm<big_endian>::set_secondary_compatible_arch(
5644 Attributes_section_data* pasd,
5647 Object_attribute *known_attributes =
5648 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
5652 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
5656 // Note: the tag and its argument below are uleb128 values, though
5657 // currently-defined values fit in one byte for each.
5659 sv[0] = elfcpp::Tag_CPU_arch;
5660 gold_assert(arch != 0);
5664 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
5667 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
5669 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
5671 template<bool big_endian>
5673 Target_arm<big_endian>::tag_cpu_arch_combine(
5676 int* secondary_compat_out,
5678 int secondary_compat)
5680 #define T(X) elfcpp::TAG_CPU_ARCH_##X
5681 static const int v6t2[] =
5693 static const int v6k[] =
5706 static const int v7[] =
5720 static const int v6_m[] =
5735 static const int v6s_m[] =
5751 static const int v7e_m[] =
5768 static const int v4t_plus_v6_m[] =
5784 T(V4T_PLUS_V6_M) // V4T plus V6_M.
5786 static const int *comb[] =
5794 // Pseudo-architecture.
5798 // Check we've not got a higher architecture than we know about.
5800 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
5802 gold_error(_("%s: unknown CPU architecture"), name);
5806 // Override old tag if we have a Tag_also_compatible_with on the output.
5808 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
5809 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
5810 oldtag = T(V4T_PLUS_V6_M);
5812 // And override the new tag if we have a Tag_also_compatible_with on the
5815 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
5816 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
5817 newtag = T(V4T_PLUS_V6_M);
5819 // Architectures before V6KZ add features monotonically.
5820 int tagh = std::max(oldtag, newtag);
5821 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
5824 int tagl = std::min(oldtag, newtag);
5825 int result = comb[tagh - T(V6T2)][tagl];
5827 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
5828 // as the canonical version.
5829 if (result == T(V4T_PLUS_V6_M))
5832 *secondary_compat_out = T(V6_M);
5835 *secondary_compat_out = -1;
5839 gold_error(_("%s: conflicting CPU architectures %d/%d"),
5840 name, oldtag, newtag);
5848 // Helper to print AEABI enum tag value.
5850 template<bool big_endian>
5852 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
5854 static const char *aeabi_enum_names[] =
5855 { "", "variable-size", "32-bit", "" };
5856 const size_t aeabi_enum_names_size =
5857 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
5859 if (value < aeabi_enum_names_size)
5860 return std::string(aeabi_enum_names[value]);
5864 sprintf(buffer, "<unknown value %u>", value);
5865 return std::string(buffer);
5869 // Return the string value to store in TAG_CPU_name.
5871 template<bool big_endian>
5873 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
5875 static const char *name_table[] = {
5876 // These aren't real CPU names, but we can't guess
5877 // that from the architecture version alone.
5893 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
5895 if (value < name_table_size)
5896 return std::string(name_table[value]);
5900 sprintf(buffer, "<unknown CPU value %u>", value);
5901 return std::string(buffer);
5905 // Merge object attributes from input file called NAME with those of the
5906 // output. The input object attributes are in the object pointed by PASD.
5908 template<bool big_endian>
5910 Target_arm<big_endian>::merge_object_attributes(
5912 const Attributes_section_data* pasd)
5914 // Return if there is no attributes section data.
5918 // If output has no object attributes, just copy.
5919 if (this->attributes_section_data_ == NULL)
5921 this->attributes_section_data_ = new Attributes_section_data(*pasd);
5925 const int vendor = Object_attribute::OBJ_ATTR_PROC;
5926 const Object_attribute* in_attr = pasd->known_attributes(vendor);
5927 Object_attribute* out_attr =
5928 this->attributes_section_data_->known_attributes(vendor);
5930 // This needs to happen before Tag_ABI_FP_number_model is merged. */
5931 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
5932 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
5934 // Ignore mismatches if the object doesn't use floating point. */
5935 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
5936 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
5937 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
5938 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0)
5939 gold_error(_("%s uses VFP register arguments, output does not"),
5943 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
5945 // Merge this attribute with existing attributes.
5948 case elfcpp::Tag_CPU_raw_name:
5949 case elfcpp::Tag_CPU_name:
5950 // These are merged after Tag_CPU_arch.
5953 case elfcpp::Tag_ABI_optimization_goals:
5954 case elfcpp::Tag_ABI_FP_optimization_goals:
5955 // Use the first value seen.
5958 case elfcpp::Tag_CPU_arch:
5960 unsigned int saved_out_attr = out_attr->int_value();
5961 // Merge Tag_CPU_arch and Tag_also_compatible_with.
5962 int secondary_compat =
5963 this->get_secondary_compatible_arch(pasd);
5964 int secondary_compat_out =
5965 this->get_secondary_compatible_arch(
5966 this->attributes_section_data_);
5967 out_attr[i].set_int_value(
5968 tag_cpu_arch_combine(name, out_attr[i].int_value(),
5969 &secondary_compat_out,
5970 in_attr[i].int_value(),
5972 this->set_secondary_compatible_arch(this->attributes_section_data_,
5973 secondary_compat_out);
5975 // Merge Tag_CPU_name and Tag_CPU_raw_name.
5976 if (out_attr[i].int_value() == saved_out_attr)
5977 ; // Leave the names alone.
5978 else if (out_attr[i].int_value() == in_attr[i].int_value())
5980 // The output architecture has been changed to match the
5981 // input architecture. Use the input names.
5982 out_attr[elfcpp::Tag_CPU_name].set_string_value(
5983 in_attr[elfcpp::Tag_CPU_name].string_value());
5984 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
5985 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
5989 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
5990 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
5993 // If we still don't have a value for Tag_CPU_name,
5994 // make one up now. Tag_CPU_raw_name remains blank.
5995 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
5997 const std::string cpu_name =
5998 this->tag_cpu_name_value(out_attr[i].int_value());
5999 // FIXME: If we see an unknown CPU, this will be set
6000 // to "<unknown CPU n>", where n is the attribute value.
6001 // This is different from BFD, which leaves the name alone.
6002 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
6007 case elfcpp::Tag_ARM_ISA_use:
6008 case elfcpp::Tag_THUMB_ISA_use:
6009 case elfcpp::Tag_WMMX_arch:
6010 case elfcpp::Tag_Advanced_SIMD_arch:
6011 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
6012 case elfcpp::Tag_ABI_FP_rounding:
6013 case elfcpp::Tag_ABI_FP_exceptions:
6014 case elfcpp::Tag_ABI_FP_user_exceptions:
6015 case elfcpp::Tag_ABI_FP_number_model:
6016 case elfcpp::Tag_VFP_HP_extension:
6017 case elfcpp::Tag_CPU_unaligned_access:
6018 case elfcpp::Tag_T2EE_use:
6019 case elfcpp::Tag_Virtualization_use:
6020 case elfcpp::Tag_MPextension_use:
6021 // Use the largest value specified.
6022 if (in_attr[i].int_value() > out_attr[i].int_value())
6023 out_attr[i].set_int_value(in_attr[i].int_value());
6026 case elfcpp::Tag_ABI_align8_preserved:
6027 case elfcpp::Tag_ABI_PCS_RO_data:
6028 // Use the smallest value specified.
6029 if (in_attr[i].int_value() < out_attr[i].int_value())
6030 out_attr[i].set_int_value(in_attr[i].int_value());
6033 case elfcpp::Tag_ABI_align8_needed:
6034 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
6035 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
6036 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
6039 // This error message should be enabled once all non-conformant
6040 // binaries in the toolchain have had the attributes set
6042 // gold_error(_("output 8-byte data alignment conflicts with %s"),
6046 case elfcpp::Tag_ABI_FP_denormal:
6047 case elfcpp::Tag_ABI_PCS_GOT_use:
6049 // These tags have 0 = don't care, 1 = strong requirement,
6050 // 2 = weak requirement.
6051 static const int order_021[3] = {0, 2, 1};
6053 // Use the "greatest" from the sequence 0, 2, 1, or the largest
6054 // value if greater than 2 (for future-proofing).
6055 if ((in_attr[i].int_value() > 2
6056 && in_attr[i].int_value() > out_attr[i].int_value())
6057 || (in_attr[i].int_value() <= 2
6058 && out_attr[i].int_value() <= 2
6059 && (order_021[in_attr[i].int_value()]
6060 > order_021[out_attr[i].int_value()])))
6061 out_attr[i].set_int_value(in_attr[i].int_value());
6065 case elfcpp::Tag_CPU_arch_profile:
6066 if (out_attr[i].int_value() != in_attr[i].int_value())
6068 // 0 will merge with anything.
6069 // 'A' and 'S' merge to 'A'.
6070 // 'R' and 'S' merge to 'R'.
6071 // 'M' and 'A|R|S' is an error.
6072 if (out_attr[i].int_value() == 0
6073 || (out_attr[i].int_value() == 'S'
6074 && (in_attr[i].int_value() == 'A'
6075 || in_attr[i].int_value() == 'R')))
6076 out_attr[i].set_int_value(in_attr[i].int_value());
6077 else if (in_attr[i].int_value() == 0
6078 || (in_attr[i].int_value() == 'S'
6079 && (out_attr[i].int_value() == 'A'
6080 || out_attr[i].int_value() == 'R')))
6085 (_("conflicting architecture profiles %c/%c"),
6086 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
6087 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
6091 case elfcpp::Tag_VFP_arch:
6108 // Values greater than 6 aren't defined, so just pick the
6110 if (in_attr[i].int_value() > 6
6111 && in_attr[i].int_value() > out_attr[i].int_value())
6113 *out_attr = *in_attr;
6116 // The output uses the superset of input features
6117 // (ISA version) and registers.
6118 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
6119 vfp_versions[out_attr[i].int_value()].ver);
6120 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
6121 vfp_versions[out_attr[i].int_value()].regs);
6122 // This assumes all possible supersets are also a valid
6125 for (newval = 6; newval > 0; newval--)
6127 if (regs == vfp_versions[newval].regs
6128 && ver == vfp_versions[newval].ver)
6131 out_attr[i].set_int_value(newval);
6134 case elfcpp::Tag_PCS_config:
6135 if (out_attr[i].int_value() == 0)
6136 out_attr[i].set_int_value(in_attr[i].int_value());
6137 else if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
6139 // It's sometimes ok to mix different configs, so this is only
6141 gold_warning(_("%s: conflicting platform configuration"), name);
6144 case elfcpp::Tag_ABI_PCS_R9_use:
6145 if (in_attr[i].int_value() != out_attr[i].int_value()
6146 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
6147 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused)
6149 gold_error(_("%s: conflicting use of R9"), name);
6151 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
6152 out_attr[i].set_int_value(in_attr[i].int_value());
6154 case elfcpp::Tag_ABI_PCS_RW_data:
6155 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
6156 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
6157 != elfcpp::AEABI_R9_SB)
6158 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
6159 != elfcpp::AEABI_R9_unused))
6161 gold_error(_("%s: SB relative addressing conflicts with use "
6165 // Use the smallest value specified.
6166 if (in_attr[i].int_value() < out_attr[i].int_value())
6167 out_attr[i].set_int_value(in_attr[i].int_value());
6169 case elfcpp::Tag_ABI_PCS_wchar_t:
6170 // FIXME: Make it possible to turn off this warning.
6171 if (out_attr[i].int_value()
6172 && in_attr[i].int_value()
6173 && out_attr[i].int_value() != in_attr[i].int_value())
6175 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
6176 "use %u-byte wchar_t; use of wchar_t values "
6177 "across objects may fail"),
6178 name, in_attr[i].int_value(),
6179 out_attr[i].int_value());
6181 else if (in_attr[i].int_value() && !out_attr[i].int_value())
6182 out_attr[i].set_int_value(in_attr[i].int_value());
6184 case elfcpp::Tag_ABI_enum_size:
6185 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
6187 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
6188 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
6190 // The existing object is compatible with anything.
6191 // Use whatever requirements the new object has.
6192 out_attr[i].set_int_value(in_attr[i].int_value());
6194 // FIXME: Make it possible to turn off this warning.
6195 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
6196 && out_attr[i].int_value() != in_attr[i].int_value())
6198 unsigned int in_value = in_attr[i].int_value();
6199 unsigned int out_value = out_attr[i].int_value();
6200 gold_warning(_("%s uses %s enums yet the output is to use "
6201 "%s enums; use of enum values across objects "
6204 this->aeabi_enum_name(in_value).c_str(),
6205 this->aeabi_enum_name(out_value).c_str());
6209 case elfcpp::Tag_ABI_VFP_args:
6212 case elfcpp::Tag_ABI_WMMX_args:
6213 if (in_attr[i].int_value() != out_attr[i].int_value())
6215 gold_error(_("%s uses iWMMXt register arguments, output does "
6220 case Object_attribute::Tag_compatibility:
6221 // Merged in target-independent code.
6223 case elfcpp::Tag_ABI_HardFP_use:
6224 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
6225 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
6226 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
6227 out_attr[i].set_int_value(3);
6228 else if (in_attr[i].int_value() > out_attr[i].int_value())
6229 out_attr[i].set_int_value(in_attr[i].int_value());
6231 case elfcpp::Tag_ABI_FP_16bit_format:
6232 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
6234 if (in_attr[i].int_value() != out_attr[i].int_value())
6235 gold_error(_("fp16 format mismatch between %s and output"),
6238 if (in_attr[i].int_value() != 0)
6239 out_attr[i].set_int_value(in_attr[i].int_value());
6242 case elfcpp::Tag_nodefaults:
6243 // This tag is set if it exists, but the value is unused (and is
6244 // typically zero). We don't actually need to do anything here -
6245 // the merge happens automatically when the type flags are merged
6248 case elfcpp::Tag_also_compatible_with:
6249 // Already done in Tag_CPU_arch.
6251 case elfcpp::Tag_conformance:
6252 // Keep the attribute if it matches. Throw it away otherwise.
6253 // No attribute means no claim to conform.
6254 if (in_attr[i].string_value() != out_attr[i].string_value())
6255 out_attr[i].set_string_value("");
6260 const char* err_object = NULL;
6262 // The "known_obj_attributes" table does contain some undefined
6263 // attributes. Ensure that there are unused.
6264 if (out_attr[i].int_value() != 0
6265 || out_attr[i].string_value() != "")
6266 err_object = "output";
6267 else if (in_attr[i].int_value() != 0
6268 || in_attr[i].string_value() != "")
6271 if (err_object != NULL)
6273 // Attribute numbers >=64 (mod 128) can be safely ignored.
6275 gold_error(_("%s: unknown mandatory EABI object attribute "
6279 gold_warning(_("%s: unknown EABI object attribute %d"),
6283 // Only pass on attributes that match in both inputs.
6284 if (!in_attr[i].matches(out_attr[i]))
6286 out_attr[i].set_int_value(0);
6287 out_attr[i].set_string_value("");
6292 // If out_attr was copied from in_attr then it won't have a type yet.
6293 if (in_attr[i].type() && !out_attr[i].type())
6294 out_attr[i].set_type(in_attr[i].type());
6297 // Merge Tag_compatibility attributes and any common GNU ones.
6298 this->attributes_section_data_->merge(name, pasd);
6300 // Check for any attributes not known on ARM.
6301 typedef Vendor_object_attributes::Other_attributes Other_attributes;
6302 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
6303 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
6304 Other_attributes* out_other_attributes =
6305 this->attributes_section_data_->other_attributes(vendor);
6306 Other_attributes::iterator out_iter = out_other_attributes->begin();
6308 while (in_iter != in_other_attributes->end()
6309 || out_iter != out_other_attributes->end())
6311 const char* err_object = NULL;
6314 // The tags for each list are in numerical order.
6315 // If the tags are equal, then merge.
6316 if (out_iter != out_other_attributes->end()
6317 && (in_iter == in_other_attributes->end()
6318 || in_iter->first > out_iter->first))
6320 // This attribute only exists in output. We can't merge, and we
6321 // don't know what the tag means, so delete it.
6322 err_object = "output";
6323 err_tag = out_iter->first;
6324 int saved_tag = out_iter->first;
6325 delete out_iter->second;
6326 out_other_attributes->erase(out_iter);
6327 out_iter = out_other_attributes->upper_bound(saved_tag);
6329 else if (in_iter != in_other_attributes->end()
6330 && (out_iter != out_other_attributes->end()
6331 || in_iter->first < out_iter->first))
6333 // This attribute only exists in input. We can't merge, and we
6334 // don't know what the tag means, so ignore it.
6336 err_tag = in_iter->first;
6339 else // The tags are equal.
6341 // As present, all attributes in the list are unknown, and
6342 // therefore can't be merged meaningfully.
6343 err_object = "output";
6344 err_tag = out_iter->first;
6346 // Only pass on attributes that match in both inputs.
6347 if (!in_iter->second->matches(*(out_iter->second)))
6349 // No match. Delete the attribute.
6350 int saved_tag = out_iter->first;
6351 delete out_iter->second;
6352 out_other_attributes->erase(out_iter);
6353 out_iter = out_other_attributes->upper_bound(saved_tag);
6357 // Matched. Keep the attribute and move to the next.
6365 // Attribute numbers >=64 (mod 128) can be safely ignored. */
6366 if ((err_tag & 127) < 64)
6368 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
6369 err_object, err_tag);
6373 gold_warning(_("%s: unknown EABI object attribute %d"),
6374 err_object, err_tag);
6380 // Return whether a relocation type used the LSB to distinguish THUMB
6382 template<bool big_endian>
6384 Target_arm<big_endian>::reloc_uses_thumb_bit(unsigned int r_type)
6388 case elfcpp::R_ARM_PC24:
6389 case elfcpp::R_ARM_ABS32:
6390 case elfcpp::R_ARM_REL32:
6391 case elfcpp::R_ARM_SBREL32:
6392 case elfcpp::R_ARM_THM_CALL:
6393 case elfcpp::R_ARM_GLOB_DAT:
6394 case elfcpp::R_ARM_JUMP_SLOT:
6395 case elfcpp::R_ARM_GOTOFF32:
6396 case elfcpp::R_ARM_PLT32:
6397 case elfcpp::R_ARM_CALL:
6398 case elfcpp::R_ARM_JUMP24:
6399 case elfcpp::R_ARM_THM_JUMP24:
6400 case elfcpp::R_ARM_SBREL31:
6401 case elfcpp::R_ARM_PREL31:
6402 case elfcpp::R_ARM_MOVW_ABS_NC:
6403 case elfcpp::R_ARM_MOVW_PREL_NC:
6404 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
6405 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
6406 case elfcpp::R_ARM_THM_JUMP19:
6407 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
6408 case elfcpp::R_ARM_ALU_PC_G0_NC:
6409 case elfcpp::R_ARM_ALU_PC_G0:
6410 case elfcpp::R_ARM_ALU_PC_G1_NC:
6411 case elfcpp::R_ARM_ALU_PC_G1:
6412 case elfcpp::R_ARM_ALU_PC_G2:
6413 case elfcpp::R_ARM_ALU_SB_G0_NC:
6414 case elfcpp::R_ARM_ALU_SB_G0:
6415 case elfcpp::R_ARM_ALU_SB_G1_NC:
6416 case elfcpp::R_ARM_ALU_SB_G1:
6417 case elfcpp::R_ARM_ALU_SB_G2:
6418 case elfcpp::R_ARM_MOVW_BREL_NC:
6419 case elfcpp::R_ARM_MOVW_BREL:
6420 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
6421 case elfcpp::R_ARM_THM_MOVW_BREL:
6428 // Stub-generation methods for Target_arm.
6430 // Make a new Arm_input_section object.
6432 template<bool big_endian>
6433 Arm_input_section<big_endian>*
6434 Target_arm<big_endian>::new_arm_input_section(
6438 Input_section_specifier iss(relobj, shndx);
6440 Arm_input_section<big_endian>* arm_input_section =
6441 new Arm_input_section<big_endian>(relobj, shndx);
6442 arm_input_section->init();
6444 // Register new Arm_input_section in map for look-up.
6445 std::pair<typename Arm_input_section_map::iterator, bool> ins =
6446 this->arm_input_section_map_.insert(std::make_pair(iss, arm_input_section));
6448 // Make sure that it we have not created another Arm_input_section
6449 // for this input section already.
6450 gold_assert(ins.second);
6452 return arm_input_section;
6455 // Find the Arm_input_section object corresponding to the SHNDX-th input
6456 // section of RELOBJ.
6458 template<bool big_endian>
6459 Arm_input_section<big_endian>*
6460 Target_arm<big_endian>::find_arm_input_section(
6462 unsigned int shndx) const
6464 Input_section_specifier iss(relobj, shndx);
6465 typename Arm_input_section_map::const_iterator p =
6466 this->arm_input_section_map_.find(iss);
6467 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
6470 // Make a new stub table.
6472 template<bool big_endian>
6473 Stub_table<big_endian>*
6474 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
6476 Stub_table<big_endian>* stub_table =
6477 new Stub_table<big_endian>(owner);
6478 this->stub_tables_.push_back(stub_table);
6480 stub_table->set_address(owner->address() + owner->data_size());
6481 stub_table->set_file_offset(owner->offset() + owner->data_size());
6482 stub_table->finalize_data_size();
6487 // Scan a relocation for stub generation.
6489 template<bool big_endian>
6491 Target_arm<big_endian>::scan_reloc_for_stub(
6492 const Relocate_info<32, big_endian>* relinfo,
6493 unsigned int r_type,
6494 const Sized_symbol<32>* gsym,
6496 const Symbol_value<32>* psymval,
6497 elfcpp::Elf_types<32>::Elf_Swxword addend,
6498 Arm_address address)
6500 typedef typename Target_arm<big_endian>::Relocate Relocate;
6502 const Arm_relobj<big_endian>* arm_relobj =
6503 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
6505 bool target_is_thumb;
6506 Symbol_value<32> symval;
6509 // This is a global symbol. Determine if we use PLT and if the
6510 // final target is THUMB.
6511 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
6513 // This uses a PLT, change the symbol value.
6514 symval.set_output_value(this->plt_section()->address()
6515 + gsym->plt_offset());
6517 target_is_thumb = false;
6519 else if (gsym->is_undefined())
6520 // There is no need to generate a stub symbol is undefined.
6525 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
6526 || (gsym->type() == elfcpp::STT_FUNC
6527 && !gsym->is_undefined()
6528 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
6533 // This is a local symbol. Determine if the final target is THUMB.
6534 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
6537 // Strip LSB if this points to a THUMB target.
6539 && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type)
6540 && ((psymval->value(arm_relobj, 0) & 1) != 0))
6542 Arm_address stripped_value =
6543 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
6544 symval.set_output_value(stripped_value);
6548 // Get the symbol value.
6549 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
6551 // Owing to pipelining, the PC relative branches below actually skip
6552 // two instructions when the branch offset is 0.
6553 Arm_address destination;
6556 case elfcpp::R_ARM_CALL:
6557 case elfcpp::R_ARM_JUMP24:
6558 case elfcpp::R_ARM_PLT32:
6560 destination = value + addend + 8;
6562 case elfcpp::R_ARM_THM_CALL:
6563 case elfcpp::R_ARM_THM_XPC22:
6564 case elfcpp::R_ARM_THM_JUMP24:
6565 case elfcpp::R_ARM_THM_JUMP19:
6567 destination = value + addend + 4;
6573 Stub_type stub_type =
6574 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
6577 // This reloc does not need a stub.
6578 if (stub_type == arm_stub_none)
6581 // Try looking up an existing stub from a stub table.
6582 Stub_table<big_endian>* stub_table =
6583 arm_relobj->stub_table(relinfo->data_shndx);
6584 gold_assert(stub_table != NULL);
6586 // Locate stub by destination.
6587 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
6589 // Create a stub if there is not one already
6590 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
6593 // create a new stub and add it to stub table.
6594 stub = this->stub_factory().make_reloc_stub(stub_type);
6595 stub_table->add_reloc_stub(stub, stub_key);
6598 // Record the destination address.
6599 stub->set_destination_address(destination
6600 | (target_is_thumb ? 1 : 0));
6603 // This function scans a relocation sections for stub generation.
6604 // The template parameter Relocate must be a class type which provides
6605 // a single function, relocate(), which implements the machine
6606 // specific part of a relocation.
6608 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
6609 // SHT_REL or SHT_RELA.
6611 // PRELOCS points to the relocation data. RELOC_COUNT is the number
6612 // of relocs. OUTPUT_SECTION is the output section.
6613 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
6614 // mapped to output offsets.
6616 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
6617 // VIEW_SIZE is the size. These refer to the input section, unless
6618 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
6619 // the output section.
6621 template<bool big_endian>
6622 template<int sh_type>
6624 Target_arm<big_endian>::scan_reloc_section_for_stubs(
6625 const Relocate_info<32, big_endian>* relinfo,
6626 const unsigned char* prelocs,
6628 Output_section* output_section,
6629 bool needs_special_offset_handling,
6630 const unsigned char* view,
6631 elfcpp::Elf_types<32>::Elf_Addr view_address,
6634 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
6635 const int reloc_size =
6636 Reloc_types<sh_type, 32, big_endian>::reloc_size;
6638 Arm_relobj<big_endian>* arm_object =
6639 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
6640 unsigned int local_count = arm_object->local_symbol_count();
6642 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
6644 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6646 Reltype reloc(prelocs);
6648 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
6649 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6650 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6652 r_type = this->get_real_reloc_type(r_type);
6654 // Only a few relocation types need stubs.
6655 if ((r_type != elfcpp::R_ARM_CALL)
6656 && (r_type != elfcpp::R_ARM_JUMP24)
6657 && (r_type != elfcpp::R_ARM_PLT32)
6658 && (r_type != elfcpp::R_ARM_THM_CALL)
6659 && (r_type != elfcpp::R_ARM_THM_XPC22)
6660 && (r_type != elfcpp::R_ARM_THM_JUMP24)
6661 && (r_type != elfcpp::R_ARM_THM_JUMP19))
6664 section_offset_type offset =
6665 convert_to_section_size_type(reloc.get_r_offset());
6667 if (needs_special_offset_handling)
6669 offset = output_section->output_offset(relinfo->object,
6670 relinfo->data_shndx,
6677 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
6678 elfcpp::Elf_types<32>::Elf_Swxword addend =
6679 stub_addend_reader(r_type, view + offset, reloc);
6681 const Sized_symbol<32>* sym;
6683 Symbol_value<32> symval;
6684 const Symbol_value<32> *psymval;
6685 if (r_sym < local_count)
6688 psymval = arm_object->local_symbol(r_sym);
6690 // If the local symbol belongs to a section we are discarding,
6691 // and that section is a debug section, try to find the
6692 // corresponding kept section and map this symbol to its
6693 // counterpart in the kept section. The symbol must not
6694 // correspond to a section we are folding.
6696 unsigned int shndx = psymval->input_shndx(&is_ordinary);
6698 && shndx != elfcpp::SHN_UNDEF
6699 && !arm_object->is_section_included(shndx)
6700 && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
6702 if (comdat_behavior == CB_UNDETERMINED)
6705 arm_object->section_name(relinfo->data_shndx);
6706 comdat_behavior = get_comdat_behavior(name.c_str());
6708 if (comdat_behavior == CB_PRETEND)
6711 typename elfcpp::Elf_types<32>::Elf_Addr value =
6712 arm_object->map_to_kept_section(shndx, &found);
6714 symval.set_output_value(value + psymval->input_value());
6716 symval.set_output_value(0);
6720 symval.set_output_value(0);
6722 symval.set_no_output_symtab_entry();
6728 const Symbol* gsym = arm_object->global_symbol(r_sym);
6729 gold_assert(gsym != NULL);
6730 if (gsym->is_forwarder())
6731 gsym = relinfo->symtab->resolve_forwards(gsym);
6733 sym = static_cast<const Sized_symbol<32>*>(gsym);
6734 if (sym->has_symtab_index())
6735 symval.set_output_symtab_index(sym->symtab_index());
6737 symval.set_no_output_symtab_entry();
6739 // We need to compute the would-be final value of this global
6741 const Symbol_table* symtab = relinfo->symtab;
6742 const Sized_symbol<32>* sized_symbol =
6743 symtab->get_sized_symbol<32>(gsym);
6744 Symbol_table::Compute_final_value_status status;
6746 symtab->compute_final_value<32>(sized_symbol, &status);
6748 // Skip this if the symbol has not output section.
6749 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
6752 symval.set_output_value(value);
6756 // If symbol is a section symbol, we don't know the actual type of
6757 // destination. Give up.
6758 if (psymval->is_section_symbol())
6761 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
6762 addend, view_address + offset);
6766 // Scan an input section for stub generation.
6768 template<bool big_endian>
6770 Target_arm<big_endian>::scan_section_for_stubs(
6771 const Relocate_info<32, big_endian>* relinfo,
6772 unsigned int sh_type,
6773 const unsigned char* prelocs,
6775 Output_section* output_section,
6776 bool needs_special_offset_handling,
6777 const unsigned char* view,
6778 Arm_address view_address,
6779 section_size_type view_size)
6781 if (sh_type == elfcpp::SHT_REL)
6782 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
6787 needs_special_offset_handling,
6791 else if (sh_type == elfcpp::SHT_RELA)
6792 // We do not support RELA type relocations yet. This is provided for
6794 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
6799 needs_special_offset_handling,
6807 // Group input sections for stub generation.
6809 // We goup input sections in an output sections so that the total size,
6810 // including any padding space due to alignment is smaller than GROUP_SIZE
6811 // unless the only input section in group is bigger than GROUP_SIZE already.
6812 // Then an ARM stub table is created to follow the last input section
6813 // in group. For each group an ARM stub table is created an is placed
6814 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
6815 // extend the group after the stub table.
6817 template<bool big_endian>
6819 Target_arm<big_endian>::group_sections(
6821 section_size_type group_size,
6822 bool stubs_always_after_branch)
6824 // Group input sections and insert stub table
6825 Layout::Section_list section_list;
6826 layout->get_allocated_sections(§ion_list);
6827 for (Layout::Section_list::const_iterator p = section_list.begin();
6828 p != section_list.end();
6831 Arm_output_section<big_endian>* output_section =
6832 Arm_output_section<big_endian>::as_arm_output_section(*p);
6833 output_section->group_sections(group_size, stubs_always_after_branch,
6838 // Relaxation hook. This is where we do stub generation.
6840 template<bool big_endian>
6842 Target_arm<big_endian>::do_relax(
6844 const Input_objects* input_objects,
6845 Symbol_table* symtab,
6848 // No need to generate stubs if this is a relocatable link.
6849 gold_assert(!parameters->options().relocatable());
6851 // If this is the first pass, we need to group input sections into
6855 // Determine the stub group size. The group size is the absolute
6856 // value of the parameter --stub-group-size. If --stub-group-size
6857 // is passed a negative value, we restict stubs to be always after
6858 // the stubbed branches.
6859 int32_t stub_group_size_param =
6860 parameters->options().stub_group_size();
6861 bool stubs_always_after_branch = stub_group_size_param < 0;
6862 section_size_type stub_group_size = abs(stub_group_size_param);
6864 if (stub_group_size == 1)
6867 // Thumb branch range is +-4MB has to be used as the default
6868 // maximum size (a given section can contain both ARM and Thumb
6869 // code, so the worst case has to be taken into account).
6871 // This value is 24K less than that, which allows for 2025
6872 // 12-byte stubs. If we exceed that, then we will fail to link.
6873 // The user will have to relink with an explicit group size
6875 stub_group_size = 4170000;
6878 group_sections(layout, stub_group_size, stubs_always_after_branch);
6881 // clear changed flags for all stub_tables
6882 typedef typename Stub_table_list::iterator Stub_table_iterator;
6883 for (Stub_table_iterator sp = this->stub_tables_.begin();
6884 sp != this->stub_tables_.end();
6886 (*sp)->set_has_been_changed(false);
6888 // scan relocs for stubs
6889 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
6890 op != input_objects->relobj_end();
6893 Arm_relobj<big_endian>* arm_relobj =
6894 Arm_relobj<big_endian>::as_arm_relobj(*op);
6895 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
6898 bool any_stub_table_changed = false;
6899 for (Stub_table_iterator sp = this->stub_tables_.begin();
6900 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
6903 if ((*sp)->has_been_changed())
6904 any_stub_table_changed = true;
6907 return any_stub_table_changed;
6912 template<bool big_endian>
6914 Target_arm<big_endian>::relocate_stub(
6916 const Relocate_info<32, big_endian>* relinfo,
6917 Output_section* output_section,
6918 unsigned char* view,
6919 Arm_address address,
6920 section_size_type view_size)
6923 const Stub_template* stub_template = stub->stub_template();
6924 for (size_t i = 0; i < stub_template->reloc_count(); i++)
6926 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
6927 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
6929 unsigned int r_type = insn->r_type();
6930 section_size_type reloc_offset = stub_template->reloc_offset(i);
6931 section_size_type reloc_size = insn->size();
6932 gold_assert(reloc_offset + reloc_size <= view_size);
6934 // This is the address of the stub destination.
6935 Arm_address target = stub->reloc_target(i);
6936 Symbol_value<32> symval;
6937 symval.set_output_value(target);
6939 // Synthesize a fake reloc just in case. We don't have a symbol so
6941 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
6942 memset(reloc_buffer, 0, sizeof(reloc_buffer));
6943 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
6944 reloc_write.put_r_offset(reloc_offset);
6945 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
6946 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
6948 relocate.relocate(relinfo, this, output_section,
6949 this->fake_relnum_for_stubs, rel, r_type,
6950 NULL, &symval, view + reloc_offset,
6951 address + reloc_offset, reloc_size);
6955 // Determine whether an object attribute tag takes an integer, a
6958 template<bool big_endian>
6960 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
6962 if (tag == Object_attribute::Tag_compatibility)
6963 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
6964 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
6965 else if (tag == elfcpp::Tag_nodefaults)
6966 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
6967 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
6968 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
6969 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
6971 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
6973 return ((tag & 1) != 0
6974 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
6975 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
6978 // Reorder attributes.
6980 // The ABI defines that Tag_conformance should be emitted first, and that
6981 // Tag_nodefaults should be second (if either is defined). This sets those
6982 // two positions, and bumps up the position of all the remaining tags to
6985 template<bool big_endian>
6987 Target_arm<big_endian>::do_attributes_order(int num) const
6989 // Reorder the known object attributes in output. We want to move
6990 // Tag_conformance to position 4 and Tag_conformance to position 5
6991 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
6993 return elfcpp::Tag_conformance;
6995 return elfcpp::Tag_nodefaults;
6996 if ((num - 2) < elfcpp::Tag_nodefaults)
6998 if ((num - 1) < elfcpp::Tag_conformance)
7003 template<bool big_endian>
7004 class Target_selector_arm : public Target_selector
7007 Target_selector_arm()
7008 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
7009 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
7013 do_instantiate_target()
7014 { return new Target_arm<big_endian>(); }
7017 Target_selector_arm<false> target_selector_arm;
7018 Target_selector_arm<true> target_selector_armbe;
7020 } // End anonymous namespace.