1 // arm.cc -- arm target support for gold.
3 // Copyright 2009, 2010 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.
38 #include "parameters.h"
45 #include "copy-relocs.h"
47 #include "target-reloc.h"
48 #include "target-select.h"
52 #include "attributes.h"
53 #include "arm-reloc-property.h"
60 template<bool big_endian>
61 class Output_data_plt_arm;
63 template<bool big_endian>
66 template<bool big_endian>
67 class Arm_input_section;
69 class Arm_exidx_cantunwind;
71 class Arm_exidx_merged_section;
73 class Arm_exidx_fixup;
75 template<bool big_endian>
76 class Arm_output_section;
78 class Arm_exidx_input_section;
80 template<bool big_endian>
83 template<bool big_endian>
84 class Arm_relocate_functions;
86 template<bool big_endian>
87 class Arm_output_data_got;
89 template<bool big_endian>
93 typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address;
95 // Maximum branch offsets for ARM, THUMB and THUMB2.
96 const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8);
97 const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8);
98 const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4);
99 const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4);
100 const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
101 const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
103 // Thread Control Block size.
104 const size_t ARM_TCB_SIZE = 8;
106 // The arm target class.
108 // This is a very simple port of gold for ARM-EABI. It is intended for
109 // supporting Android only for the time being.
112 // - Implement all static relocation types documented in arm-reloc.def.
113 // - Make PLTs more flexible for different architecture features like
115 // There are probably a lot more.
117 // Ideally we would like to avoid using global variables but this is used
118 // very in many places and sometimes in loops. If we use a function
119 // returning a static instance of Arm_reloc_property_table, it will very
120 // slow in an threaded environment since the static instance needs to be
121 // locked. The pointer is below initialized in the
122 // Target::do_select_as_default_target() hook so that we do not spend time
123 // building the table if we are not linking ARM objects.
125 // An alternative is to to process the information in arm-reloc.def in
126 // compilation time and generate a representation of it in PODs only. That
127 // way we can avoid initialization when the linker starts.
129 Arm_reloc_property_table *arm_reloc_property_table = NULL;
131 // Instruction template class. This class is similar to the insn_sequence
132 // struct in bfd/elf32-arm.c.
137 // Types of instruction templates.
141 // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
142 // templates with class-specific semantics. Currently this is used
143 // only by the Cortex_a8_stub class for handling condition codes in
144 // conditional branches.
145 THUMB16_SPECIAL_TYPE,
151 // Factory methods to create instruction templates in different formats.
153 static const Insn_template
154 thumb16_insn(uint32_t data)
155 { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
157 // A Thumb conditional branch, in which the proper condition is inserted
158 // when we build the stub.
159 static const Insn_template
160 thumb16_bcond_insn(uint32_t data)
161 { return Insn_template(data, THUMB16_SPECIAL_TYPE, elfcpp::R_ARM_NONE, 1); }
163 static const Insn_template
164 thumb32_insn(uint32_t data)
165 { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); }
167 static const Insn_template
168 thumb32_b_insn(uint32_t data, int reloc_addend)
170 return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24,
174 static const Insn_template
175 arm_insn(uint32_t data)
176 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); }
178 static const Insn_template
179 arm_rel_insn(unsigned data, int reloc_addend)
180 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); }
182 static const Insn_template
183 data_word(unsigned data, unsigned int r_type, int reloc_addend)
184 { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); }
186 // Accessors. This class is used for read-only objects so no modifiers
191 { return this->data_; }
193 // Return the instruction sequence type of this.
196 { return this->type_; }
198 // Return the ARM relocation type of this.
201 { return this->r_type_; }
205 { return this->reloc_addend_; }
207 // Return size of instruction template in bytes.
211 // Return byte-alignment of instruction template.
216 // We make the constructor private to ensure that only the factory
219 Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend)
220 : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend)
223 // Instruction specific data. This is used to store information like
224 // some of the instruction bits.
226 // Instruction template type.
228 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
229 unsigned int r_type_;
230 // Relocation addend.
231 int32_t reloc_addend_;
234 // Macro for generating code to stub types. One entry per long/short
238 DEF_STUB(long_branch_any_any) \
239 DEF_STUB(long_branch_v4t_arm_thumb) \
240 DEF_STUB(long_branch_thumb_only) \
241 DEF_STUB(long_branch_v4t_thumb_thumb) \
242 DEF_STUB(long_branch_v4t_thumb_arm) \
243 DEF_STUB(short_branch_v4t_thumb_arm) \
244 DEF_STUB(long_branch_any_arm_pic) \
245 DEF_STUB(long_branch_any_thumb_pic) \
246 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
247 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
248 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
249 DEF_STUB(long_branch_thumb_only_pic) \
250 DEF_STUB(a8_veneer_b_cond) \
251 DEF_STUB(a8_veneer_b) \
252 DEF_STUB(a8_veneer_bl) \
253 DEF_STUB(a8_veneer_blx) \
254 DEF_STUB(v4_veneer_bx)
258 #define DEF_STUB(x) arm_stub_##x,
264 // First reloc stub type.
265 arm_stub_reloc_first = arm_stub_long_branch_any_any,
266 // Last reloc stub type.
267 arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic,
269 // First Cortex-A8 stub type.
270 arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond,
271 // Last Cortex-A8 stub type.
272 arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
275 arm_stub_type_last = arm_stub_v4_veneer_bx
279 // Stub template class. Templates are meant to be read-only objects.
280 // A stub template for a stub type contains all read-only attributes
281 // common to all stubs of the same type.
286 Stub_template(Stub_type, const Insn_template*, size_t);
294 { return this->type_; }
296 // Return an array of instruction templates.
299 { return this->insns_; }
301 // Return size of template in number of instructions.
304 { return this->insn_count_; }
306 // Return size of template in bytes.
309 { return this->size_; }
311 // Return alignment of the stub template.
314 { return this->alignment_; }
316 // Return whether entry point is in thumb mode.
318 entry_in_thumb_mode() const
319 { return this->entry_in_thumb_mode_; }
321 // Return number of relocations in this template.
324 { return this->relocs_.size(); }
326 // Return index of the I-th instruction with relocation.
328 reloc_insn_index(size_t i) const
330 gold_assert(i < this->relocs_.size());
331 return this->relocs_[i].first;
334 // Return the offset of the I-th instruction with relocation from the
335 // beginning of the stub.
337 reloc_offset(size_t i) const
339 gold_assert(i < this->relocs_.size());
340 return this->relocs_[i].second;
344 // This contains information about an instruction template with a relocation
345 // and its offset from start of stub.
346 typedef std::pair<size_t, section_size_type> Reloc;
348 // A Stub_template may not be copied. We want to share templates as much
350 Stub_template(const Stub_template&);
351 Stub_template& operator=(const Stub_template&);
355 // Points to an array of Insn_templates.
356 const Insn_template* insns_;
357 // Number of Insn_templates in insns_[].
359 // Size of templated instructions in bytes.
361 // Alignment of templated instructions.
363 // Flag to indicate if entry is in thumb mode.
364 bool entry_in_thumb_mode_;
365 // A table of reloc instruction indices and offsets. We can find these by
366 // looking at the instruction templates but we pre-compute and then stash
367 // them here for speed.
368 std::vector<Reloc> relocs_;
372 // A class for code stubs. This is a base class for different type of
373 // stubs used in the ARM target.
379 static const section_offset_type invalid_offset =
380 static_cast<section_offset_type>(-1);
383 Stub(const Stub_template* stub_template)
384 : stub_template_(stub_template), offset_(invalid_offset)
391 // Return the stub template.
393 stub_template() const
394 { return this->stub_template_; }
396 // Return offset of code stub from beginning of its containing stub table.
400 gold_assert(this->offset_ != invalid_offset);
401 return this->offset_;
404 // Set offset of code stub from beginning of its containing stub table.
406 set_offset(section_offset_type offset)
407 { this->offset_ = offset; }
409 // Return the relocation target address of the i-th relocation in the
410 // stub. This must be defined in a child class.
412 reloc_target(size_t i)
413 { return this->do_reloc_target(i); }
415 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
417 write(unsigned char* view, section_size_type view_size, bool big_endian)
418 { this->do_write(view, view_size, big_endian); }
420 // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
421 // for the i-th instruction.
423 thumb16_special(size_t i)
424 { return this->do_thumb16_special(i); }
427 // This must be defined in the child class.
429 do_reloc_target(size_t) = 0;
431 // This may be overridden in the child class.
433 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
436 this->do_fixed_endian_write<true>(view, view_size);
438 this->do_fixed_endian_write<false>(view, view_size);
441 // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
442 // instruction template.
444 do_thumb16_special(size_t)
445 { gold_unreachable(); }
448 // A template to implement do_write.
449 template<bool big_endian>
451 do_fixed_endian_write(unsigned char*, section_size_type);
454 const Stub_template* stub_template_;
455 // Offset within the section of containing this stub.
456 section_offset_type offset_;
459 // Reloc stub class. These are stubs we use to fix up relocation because
460 // of limited branch ranges.
462 class Reloc_stub : public Stub
465 static const unsigned int invalid_index = static_cast<unsigned int>(-1);
466 // We assume we never jump to this address.
467 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
469 // Return destination address.
471 destination_address() const
473 gold_assert(this->destination_address_ != this->invalid_address);
474 return this->destination_address_;
477 // Set destination address.
479 set_destination_address(Arm_address address)
481 gold_assert(address != this->invalid_address);
482 this->destination_address_ = address;
485 // Reset destination address.
487 reset_destination_address()
488 { this->destination_address_ = this->invalid_address; }
490 // Determine stub type for a branch of a relocation of R_TYPE going
491 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
492 // the branch target is a thumb instruction. TARGET is used for look
493 // up ARM-specific linker settings.
495 stub_type_for_reloc(unsigned int r_type, Arm_address branch_address,
496 Arm_address branch_target, bool target_is_thumb);
498 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
499 // and an addend. Since we treat global and local symbol differently, we
500 // use a Symbol object for a global symbol and a object-index pair for
505 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
506 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
507 // and R_SYM must not be invalid_index.
508 Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj,
509 unsigned int r_sym, int32_t addend)
510 : stub_type_(stub_type), addend_(addend)
514 this->r_sym_ = Reloc_stub::invalid_index;
515 this->u_.symbol = symbol;
519 gold_assert(relobj != NULL && r_sym != invalid_index);
520 this->r_sym_ = r_sym;
521 this->u_.relobj = relobj;
528 // Accessors: Keys are meant to be read-only object so no modifiers are
534 { return this->stub_type_; }
536 // Return the local symbol index or invalid_index.
539 { return this->r_sym_; }
541 // Return the symbol if there is one.
544 { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
546 // Return the relobj if there is one.
549 { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
551 // Whether this equals to another key k.
553 eq(const Key& k) const
555 return ((this->stub_type_ == k.stub_type_)
556 && (this->r_sym_ == k.r_sym_)
557 && ((this->r_sym_ != Reloc_stub::invalid_index)
558 ? (this->u_.relobj == k.u_.relobj)
559 : (this->u_.symbol == k.u_.symbol))
560 && (this->addend_ == k.addend_));
563 // Return a hash value.
567 return (this->stub_type_
569 ^ gold::string_hash<char>(
570 (this->r_sym_ != Reloc_stub::invalid_index)
571 ? this->u_.relobj->name().c_str()
572 : this->u_.symbol->name())
576 // Functors for STL associative containers.
580 operator()(const Key& k) const
581 { return k.hash_value(); }
587 operator()(const Key& k1, const Key& k2) const
588 { return k1.eq(k2); }
591 // Name of key. This is mainly for debugging.
597 Stub_type stub_type_;
598 // If this is a local symbol, this is the index in the defining object.
599 // Otherwise, it is invalid_index for a global symbol.
601 // If r_sym_ is invalid index. This points to a global symbol.
602 // Otherwise, this points a relobj. We used the unsized and target
603 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
604 // Arm_relobj. This is done to avoid making the stub class a template
605 // as most of the stub machinery is endianity-neutral. However, it
606 // may require a bit of casting done by users of this class.
609 const Symbol* symbol;
610 const Relobj* relobj;
612 // Addend associated with a reloc.
617 // Reloc_stubs are created via a stub factory. So these are protected.
618 Reloc_stub(const Stub_template* stub_template)
619 : Stub(stub_template), destination_address_(invalid_address)
625 friend class Stub_factory;
627 // Return the relocation target address of the i-th relocation in the
630 do_reloc_target(size_t i)
632 // All reloc stub have only one relocation.
634 return this->destination_address_;
638 // Address of destination.
639 Arm_address destination_address_;
642 // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
643 // THUMB branch that meets the following conditions:
645 // 1. The branch straddles across a page boundary. i.e. lower 12-bit of
646 // branch address is 0xffe.
647 // 2. The branch target address is in the same page as the first word of the
649 // 3. The branch follows a 32-bit instruction which is not a branch.
651 // To do the fix up, we need to store the address of the branch instruction
652 // and its target at least. We also need to store the original branch
653 // instruction bits for the condition code in a conditional branch. The
654 // condition code is used in a special instruction template. We also want
655 // to identify input sections needing Cortex-A8 workaround quickly. We store
656 // extra information about object and section index of the code section
657 // containing a branch being fixed up. The information is used to mark
658 // the code section when we finalize the Cortex-A8 stubs.
661 class Cortex_a8_stub : public Stub
667 // Return the object of the code section containing the branch being fixed
671 { return this->relobj_; }
673 // Return the section index of the code section containing the branch being
677 { return this->shndx_; }
679 // Return the source address of stub. This is the address of the original
680 // branch instruction. LSB is 1 always set to indicate that it is a THUMB
683 source_address() const
684 { return this->source_address_; }
686 // Return the destination address of the stub. This is the branch taken
687 // address of the original branch instruction. LSB is 1 if it is a THUMB
688 // instruction address.
690 destination_address() const
691 { return this->destination_address_; }
693 // Return the instruction being fixed up.
695 original_insn() const
696 { return this->original_insn_; }
699 // Cortex_a8_stubs are created via a stub factory. So these are protected.
700 Cortex_a8_stub(const Stub_template* stub_template, Relobj* relobj,
701 unsigned int shndx, Arm_address source_address,
702 Arm_address destination_address, uint32_t original_insn)
703 : Stub(stub_template), relobj_(relobj), shndx_(shndx),
704 source_address_(source_address | 1U),
705 destination_address_(destination_address),
706 original_insn_(original_insn)
709 friend class Stub_factory;
711 // Return the relocation target address of the i-th relocation in the
714 do_reloc_target(size_t i)
716 if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond)
718 // The conditional branch veneer has two relocations.
720 return i == 0 ? this->source_address_ + 4 : this->destination_address_;
724 // All other Cortex-A8 stubs have only one relocation.
726 return this->destination_address_;
730 // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
732 do_thumb16_special(size_t);
735 // Object of the code section containing the branch being fixed up.
737 // Section index of the code section containing the branch begin fixed up.
739 // Source address of original branch.
740 Arm_address source_address_;
741 // Destination address of the original branch.
742 Arm_address destination_address_;
743 // Original branch instruction. This is needed for copying the condition
744 // code from a condition branch to its stub.
745 uint32_t original_insn_;
748 // ARMv4 BX Rx branch relocation stub class.
749 class Arm_v4bx_stub : public Stub
755 // Return the associated register.
758 { return this->reg_; }
761 // Arm V4BX stubs are created via a stub factory. So these are protected.
762 Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg)
763 : Stub(stub_template), reg_(reg)
766 friend class Stub_factory;
768 // Return the relocation target address of the i-th relocation in the
771 do_reloc_target(size_t)
772 { gold_unreachable(); }
774 // This may be overridden in the child class.
776 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
779 this->do_fixed_endian_v4bx_write<true>(view, view_size);
781 this->do_fixed_endian_v4bx_write<false>(view, view_size);
785 // A template to implement do_write.
786 template<bool big_endian>
788 do_fixed_endian_v4bx_write(unsigned char* view, section_size_type)
790 const Insn_template* insns = this->stub_template()->insns();
791 elfcpp::Swap<32, big_endian>::writeval(view,
793 + (this->reg_ << 16)));
794 view += insns[0].size();
795 elfcpp::Swap<32, big_endian>::writeval(view,
796 (insns[1].data() + this->reg_));
797 view += insns[1].size();
798 elfcpp::Swap<32, big_endian>::writeval(view,
799 (insns[2].data() + this->reg_));
802 // A register index (r0-r14), which is associated with the stub.
806 // Stub factory class.
811 // Return the unique instance of this class.
812 static const Stub_factory&
815 static Stub_factory singleton;
819 // Make a relocation stub.
821 make_reloc_stub(Stub_type stub_type) const
823 gold_assert(stub_type >= arm_stub_reloc_first
824 && stub_type <= arm_stub_reloc_last);
825 return new Reloc_stub(this->stub_templates_[stub_type]);
828 // Make a Cortex-A8 stub.
830 make_cortex_a8_stub(Stub_type stub_type, Relobj* relobj, unsigned int shndx,
831 Arm_address source, Arm_address destination,
832 uint32_t original_insn) const
834 gold_assert(stub_type >= arm_stub_cortex_a8_first
835 && stub_type <= arm_stub_cortex_a8_last);
836 return new Cortex_a8_stub(this->stub_templates_[stub_type], relobj, shndx,
837 source, destination, original_insn);
840 // Make an ARM V4BX relocation stub.
841 // This method creates a stub from the arm_stub_v4_veneer_bx template only.
843 make_arm_v4bx_stub(uint32_t reg) const
845 gold_assert(reg < 0xf);
846 return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx],
851 // Constructor and destructor are protected since we only return a single
852 // instance created in Stub_factory::get_instance().
856 // A Stub_factory may not be copied since it is a singleton.
857 Stub_factory(const Stub_factory&);
858 Stub_factory& operator=(Stub_factory&);
860 // Stub templates. These are initialized in the constructor.
861 const Stub_template* stub_templates_[arm_stub_type_last+1];
864 // A class to hold stubs for the ARM target.
866 template<bool big_endian>
867 class Stub_table : public Output_data
870 Stub_table(Arm_input_section<big_endian>* owner)
871 : Output_data(), owner_(owner), reloc_stubs_(), reloc_stubs_size_(0),
872 reloc_stubs_addralign_(1), cortex_a8_stubs_(), arm_v4bx_stubs_(0xf),
873 prev_data_size_(0), prev_addralign_(1)
879 // Owner of this stub table.
880 Arm_input_section<big_endian>*
882 { return this->owner_; }
884 // Whether this stub table is empty.
888 return (this->reloc_stubs_.empty()
889 && this->cortex_a8_stubs_.empty()
890 && this->arm_v4bx_stubs_.empty());
893 // Return the current data size.
895 current_data_size() const
896 { return this->current_data_size_for_child(); }
898 // Add a STUB with using KEY. Caller is reponsible for avoid adding
899 // if already a STUB with the same key has been added.
901 add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key)
903 const Stub_template* stub_template = stub->stub_template();
904 gold_assert(stub_template->type() == key.stub_type());
905 this->reloc_stubs_[key] = stub;
907 // Assign stub offset early. We can do this because we never remove
908 // reloc stubs and they are in the beginning of the stub table.
909 uint64_t align = stub_template->alignment();
910 this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_, align);
911 stub->set_offset(this->reloc_stubs_size_);
912 this->reloc_stubs_size_ += stub_template->size();
913 this->reloc_stubs_addralign_ =
914 std::max(this->reloc_stubs_addralign_, align);
917 // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
918 // Caller is reponsible for avoid adding if already a STUB with the same
919 // address has been added.
921 add_cortex_a8_stub(Arm_address address, Cortex_a8_stub* stub)
923 std::pair<Arm_address, Cortex_a8_stub*> value(address, stub);
924 this->cortex_a8_stubs_.insert(value);
927 // Add an ARM V4BX relocation stub. A register index will be retrieved
930 add_arm_v4bx_stub(Arm_v4bx_stub* stub)
932 gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL);
933 this->arm_v4bx_stubs_[stub->reg()] = stub;
936 // Remove all Cortex-A8 stubs.
938 remove_all_cortex_a8_stubs();
940 // Look up a relocation stub using KEY. Return NULL if there is none.
942 find_reloc_stub(const Reloc_stub::Key& key) const
944 typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
945 return (p != this->reloc_stubs_.end()) ? p->second : NULL;
948 // Look up an arm v4bx relocation stub using the register index.
949 // Return NULL if there is none.
951 find_arm_v4bx_stub(const uint32_t reg) const
953 gold_assert(reg < 0xf);
954 return this->arm_v4bx_stubs_[reg];
957 // Relocate stubs in this stub table.
959 relocate_stubs(const Relocate_info<32, big_endian>*,
960 Target_arm<big_endian>*, Output_section*,
961 unsigned char*, Arm_address, section_size_type);
963 // Update data size and alignment at the end of a relaxation pass. Return
964 // true if either data size or alignment is different from that of the
965 // previous relaxation pass.
967 update_data_size_and_addralign();
969 // Finalize stubs. Set the offsets of all stubs and mark input sections
970 // needing the Cortex-A8 workaround.
974 // Apply Cortex-A8 workaround to an address range.
976 apply_cortex_a8_workaround_to_address_range(Target_arm<big_endian>*,
977 unsigned char*, Arm_address,
981 // Write out section contents.
983 do_write(Output_file*);
985 // Return the required alignment.
988 { return this->prev_addralign_; }
990 // Reset address and file offset.
992 do_reset_address_and_file_offset()
993 { this->set_current_data_size_for_child(this->prev_data_size_); }
995 // Set final data size.
997 set_final_data_size()
998 { this->set_data_size(this->current_data_size()); }
1001 // Relocate one stub.
1003 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
1004 Target_arm<big_endian>*, Output_section*,
1005 unsigned char*, Arm_address, section_size_type);
1007 // Unordered map of relocation stubs.
1009 Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
1010 Reloc_stub::Key::equal_to>
1013 // List of Cortex-A8 stubs ordered by addresses of branches being
1014 // fixed up in output.
1015 typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list;
1016 // List of Arm V4BX relocation stubs ordered by associated registers.
1017 typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list;
1019 // Owner of this stub table.
1020 Arm_input_section<big_endian>* owner_;
1021 // The relocation stubs.
1022 Reloc_stub_map reloc_stubs_;
1023 // Size of reloc stubs.
1024 off_t reloc_stubs_size_;
1025 // Maximum address alignment of reloc stubs.
1026 uint64_t reloc_stubs_addralign_;
1027 // The cortex_a8_stubs.
1028 Cortex_a8_stub_list cortex_a8_stubs_;
1029 // The Arm V4BX relocation stubs.
1030 Arm_v4bx_stub_list arm_v4bx_stubs_;
1031 // data size of this in the previous pass.
1032 off_t prev_data_size_;
1033 // address alignment of this in the previous pass.
1034 uint64_t prev_addralign_;
1037 // Arm_exidx_cantunwind class. This represents an EXIDX_CANTUNWIND entry
1038 // we add to the end of an EXIDX input section that goes into the output.
1040 class Arm_exidx_cantunwind : public Output_section_data
1043 Arm_exidx_cantunwind(Relobj* relobj, unsigned int shndx)
1044 : Output_section_data(8, 4, true), relobj_(relobj), shndx_(shndx)
1047 // Return the object containing the section pointed by this.
1050 { return this->relobj_; }
1052 // Return the section index of the section pointed by this.
1055 { return this->shndx_; }
1059 do_write(Output_file* of)
1061 if (parameters->target().is_big_endian())
1062 this->do_fixed_endian_write<true>(of);
1064 this->do_fixed_endian_write<false>(of);
1068 // Implement do_write for a given endianity.
1069 template<bool big_endian>
1071 do_fixed_endian_write(Output_file*);
1073 // The object containing the section pointed by this.
1075 // The section index of the section pointed by this.
1076 unsigned int shndx_;
1079 // During EXIDX coverage fix-up, we compact an EXIDX section. The
1080 // Offset map is used to map input section offset within the EXIDX section
1081 // to the output offset from the start of this EXIDX section.
1083 typedef std::map<section_offset_type, section_offset_type>
1084 Arm_exidx_section_offset_map;
1086 // Arm_exidx_merged_section class. This represents an EXIDX input section
1087 // with some of its entries merged.
1089 class Arm_exidx_merged_section : public Output_relaxed_input_section
1092 // Constructor for Arm_exidx_merged_section.
1093 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
1094 // SECTION_OFFSET_MAP points to a section offset map describing how
1095 // parts of the input section are mapped to output. DELETED_BYTES is
1096 // the number of bytes deleted from the EXIDX input section.
1097 Arm_exidx_merged_section(
1098 const Arm_exidx_input_section& exidx_input_section,
1099 const Arm_exidx_section_offset_map& section_offset_map,
1100 uint32_t deleted_bytes);
1102 // Return the original EXIDX input section.
1103 const Arm_exidx_input_section&
1104 exidx_input_section() const
1105 { return this->exidx_input_section_; }
1107 // Return the section offset map.
1108 const Arm_exidx_section_offset_map&
1109 section_offset_map() const
1110 { return this->section_offset_map_; }
1113 // Write merged section into file OF.
1115 do_write(Output_file* of);
1118 do_output_offset(const Relobj*, unsigned int, section_offset_type,
1119 section_offset_type*) const;
1122 // Original EXIDX input section.
1123 const Arm_exidx_input_section& exidx_input_section_;
1124 // Section offset map.
1125 const Arm_exidx_section_offset_map& section_offset_map_;
1128 // A class to wrap an ordinary input section containing executable code.
1130 template<bool big_endian>
1131 class Arm_input_section : public Output_relaxed_input_section
1134 Arm_input_section(Relobj* relobj, unsigned int shndx)
1135 : Output_relaxed_input_section(relobj, shndx, 1),
1136 original_addralign_(1), original_size_(0), stub_table_(NULL)
1139 ~Arm_input_section()
1146 // Whether this is a stub table owner.
1148 is_stub_table_owner() const
1149 { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
1151 // Return the stub table.
1152 Stub_table<big_endian>*
1154 { return this->stub_table_; }
1156 // Set the stub_table.
1158 set_stub_table(Stub_table<big_endian>* stub_table)
1159 { this->stub_table_ = stub_table; }
1161 // Downcast a base pointer to an Arm_input_section pointer. This is
1162 // not type-safe but we only use Arm_input_section not the base class.
1163 static Arm_input_section<big_endian>*
1164 as_arm_input_section(Output_relaxed_input_section* poris)
1165 { return static_cast<Arm_input_section<big_endian>*>(poris); }
1168 // Write data to output file.
1170 do_write(Output_file*);
1172 // Return required alignment of this.
1174 do_addralign() const
1176 if (this->is_stub_table_owner())
1177 return std::max(this->stub_table_->addralign(),
1178 this->original_addralign_);
1180 return this->original_addralign_;
1183 // Finalize data size.
1185 set_final_data_size();
1187 // Reset address and file offset.
1189 do_reset_address_and_file_offset();
1193 do_output_offset(const Relobj* object, unsigned int shndx,
1194 section_offset_type offset,
1195 section_offset_type* poutput) const
1197 if ((object == this->relobj())
1198 && (shndx == this->shndx())
1200 && (convert_types<uint64_t, section_offset_type>(offset)
1201 <= this->original_size_))
1211 // Copying is not allowed.
1212 Arm_input_section(const Arm_input_section&);
1213 Arm_input_section& operator=(const Arm_input_section&);
1215 // Address alignment of the original input section.
1216 uint64_t original_addralign_;
1217 // Section size of the original input section.
1218 uint64_t original_size_;
1220 Stub_table<big_endian>* stub_table_;
1223 // Arm_exidx_fixup class. This is used to define a number of methods
1224 // and keep states for fixing up EXIDX coverage.
1226 class Arm_exidx_fixup
1229 Arm_exidx_fixup(Output_section* exidx_output_section)
1230 : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
1231 last_inlined_entry_(0), last_input_section_(NULL),
1232 section_offset_map_(NULL), first_output_text_section_(NULL)
1236 { delete this->section_offset_map_; }
1238 // Process an EXIDX section for entry merging. Return number of bytes to
1239 // be deleted in output. If parts of the input EXIDX section are merged
1240 // a heap allocated Arm_exidx_section_offset_map is store in the located
1241 // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
1243 template<bool big_endian>
1245 process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
1246 Arm_exidx_section_offset_map** psection_offset_map);
1248 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1249 // input section, if there is not one already.
1251 add_exidx_cantunwind_as_needed();
1253 // Return the output section for the text section which is linked to the
1254 // first exidx input in output.
1256 first_output_text_section() const
1257 { return this->first_output_text_section_; }
1260 // Copying is not allowed.
1261 Arm_exidx_fixup(const Arm_exidx_fixup&);
1262 Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
1264 // Type of EXIDX unwind entry.
1269 // EXIDX_CANTUNWIND.
1270 UT_EXIDX_CANTUNWIND,
1277 // Process an EXIDX entry. We only care about the second word of the
1278 // entry. Return true if the entry can be deleted.
1280 process_exidx_entry(uint32_t second_word);
1282 // Update the current section offset map during EXIDX section fix-up.
1283 // If there is no map, create one. INPUT_OFFSET is the offset of a
1284 // reference point, DELETED_BYTES is the number of deleted by in the
1285 // section so far. If DELETE_ENTRY is true, the reference point and
1286 // all offsets after the previous reference point are discarded.
1288 update_offset_map(section_offset_type input_offset,
1289 section_size_type deleted_bytes, bool delete_entry);
1291 // EXIDX output section.
1292 Output_section* exidx_output_section_;
1293 // Unwind type of the last EXIDX entry processed.
1294 Unwind_type last_unwind_type_;
1295 // Last seen inlined EXIDX entry.
1296 uint32_t last_inlined_entry_;
1297 // Last processed EXIDX input section.
1298 const Arm_exidx_input_section* last_input_section_;
1299 // Section offset map created in process_exidx_section.
1300 Arm_exidx_section_offset_map* section_offset_map_;
1301 // Output section for the text section which is linked to the first exidx
1303 Output_section* first_output_text_section_;
1306 // Arm output section class. This is defined mainly to add a number of
1307 // stub generation methods.
1309 template<bool big_endian>
1310 class Arm_output_section : public Output_section
1313 typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
1315 Arm_output_section(const char* name, elfcpp::Elf_Word type,
1316 elfcpp::Elf_Xword flags)
1317 : Output_section(name, type, flags)
1320 ~Arm_output_section()
1323 // Group input sections for stub generation.
1325 group_sections(section_size_type, bool, Target_arm<big_endian>*);
1327 // Downcast a base pointer to an Arm_output_section pointer. This is
1328 // not type-safe but we only use Arm_output_section not the base class.
1329 static Arm_output_section<big_endian>*
1330 as_arm_output_section(Output_section* os)
1331 { return static_cast<Arm_output_section<big_endian>*>(os); }
1333 // Append all input text sections in this into LIST.
1335 append_text_sections_to_list(Text_section_list* list);
1337 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1338 // is a list of text input sections sorted in ascending order of their
1339 // output addresses.
1341 fix_exidx_coverage(Layout* layout,
1342 const Text_section_list& sorted_text_section,
1343 Symbol_table* symtab);
1347 typedef Output_section::Input_section Input_section;
1348 typedef Output_section::Input_section_list Input_section_list;
1350 // Create a stub group.
1351 void create_stub_group(Input_section_list::const_iterator,
1352 Input_section_list::const_iterator,
1353 Input_section_list::const_iterator,
1354 Target_arm<big_endian>*,
1355 std::vector<Output_relaxed_input_section*>*);
1358 // Arm_exidx_input_section class. This represents an EXIDX input section.
1360 class Arm_exidx_input_section
1363 static const section_offset_type invalid_offset =
1364 static_cast<section_offset_type>(-1);
1366 Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
1367 unsigned int link, uint32_t size, uint32_t addralign)
1368 : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
1369 addralign_(addralign)
1372 ~Arm_exidx_input_section()
1375 // Accessors: This is a read-only class.
1377 // Return the object containing this EXIDX input section.
1380 { return this->relobj_; }
1382 // Return the section index of this EXIDX input section.
1385 { return this->shndx_; }
1387 // Return the section index of linked text section in the same object.
1390 { return this->link_; }
1392 // Return size of the EXIDX input section.
1395 { return this->size_; }
1397 // Reutnr address alignment of EXIDX input section.
1400 { return this->addralign_; }
1403 // Object containing this.
1405 // Section index of this.
1406 unsigned int shndx_;
1407 // text section linked to this in the same object.
1409 // Size of this. For ARM 32-bit is sufficient.
1411 // Address alignment of this. For ARM 32-bit is sufficient.
1412 uint32_t addralign_;
1415 // Arm_relobj class.
1417 template<bool big_endian>
1418 class Arm_relobj : public Sized_relobj<32, big_endian>
1421 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
1423 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
1424 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
1425 : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
1426 stub_tables_(), local_symbol_is_thumb_function_(),
1427 attributes_section_data_(NULL), mapping_symbols_info_(),
1428 section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
1429 output_local_symbol_count_needs_update_(false)
1433 { delete this->attributes_section_data_; }
1435 // Return the stub table of the SHNDX-th section if there is one.
1436 Stub_table<big_endian>*
1437 stub_table(unsigned int shndx) const
1439 gold_assert(shndx < this->stub_tables_.size());
1440 return this->stub_tables_[shndx];
1443 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1445 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
1447 gold_assert(shndx < this->stub_tables_.size());
1448 this->stub_tables_[shndx] = stub_table;
1451 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1452 // index. This is only valid after do_count_local_symbol is called.
1454 local_symbol_is_thumb_function(unsigned int r_sym) const
1456 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
1457 return this->local_symbol_is_thumb_function_[r_sym];
1460 // Scan all relocation sections for stub generation.
1462 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
1465 // Convert regular input section with index SHNDX to a relaxed section.
1467 convert_input_section_to_relaxed_section(unsigned shndx)
1469 // The stubs have relocations and we need to process them after writing
1470 // out the stubs. So relocation now must follow section write.
1471 this->set_section_offset(shndx, -1ULL);
1472 this->set_relocs_must_follow_section_writes();
1475 // Downcast a base pointer to an Arm_relobj pointer. This is
1476 // not type-safe but we only use Arm_relobj not the base class.
1477 static Arm_relobj<big_endian>*
1478 as_arm_relobj(Relobj* relobj)
1479 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
1481 // Processor-specific flags in ELF file header. This is valid only after
1484 processor_specific_flags() const
1485 { return this->processor_specific_flags_; }
1487 // Attribute section data This is the contents of the .ARM.attribute section
1489 const Attributes_section_data*
1490 attributes_section_data() const
1491 { return this->attributes_section_data_; }
1493 // Mapping symbol location.
1494 typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
1496 // Functor for STL container.
1497 struct Mapping_symbol_position_less
1500 operator()(const Mapping_symbol_position& p1,
1501 const Mapping_symbol_position& p2) const
1503 return (p1.first < p2.first
1504 || (p1.first == p2.first && p1.second < p2.second));
1508 // We only care about the first character of a mapping symbol, so
1509 // we only store that instead of the whole symbol name.
1510 typedef std::map<Mapping_symbol_position, char,
1511 Mapping_symbol_position_less> Mapping_symbols_info;
1513 // Whether a section contains any Cortex-A8 workaround.
1515 section_has_cortex_a8_workaround(unsigned int shndx) const
1517 return (this->section_has_cortex_a8_workaround_ != NULL
1518 && (*this->section_has_cortex_a8_workaround_)[shndx]);
1521 // Mark a section that has Cortex-A8 workaround.
1523 mark_section_for_cortex_a8_workaround(unsigned int shndx)
1525 if (this->section_has_cortex_a8_workaround_ == NULL)
1526 this->section_has_cortex_a8_workaround_ =
1527 new std::vector<bool>(this->shnum(), false);
1528 (*this->section_has_cortex_a8_workaround_)[shndx] = true;
1531 // Return the EXIDX section of an text section with index SHNDX or NULL
1532 // if the text section has no associated EXIDX section.
1533 const Arm_exidx_input_section*
1534 exidx_input_section_by_link(unsigned int shndx) const
1536 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1537 return ((p != this->exidx_section_map_.end()
1538 && p->second->link() == shndx)
1543 // Return the EXIDX section with index SHNDX or NULL if there is none.
1544 const Arm_exidx_input_section*
1545 exidx_input_section_by_shndx(unsigned shndx) const
1547 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1548 return ((p != this->exidx_section_map_.end()
1549 && p->second->shndx() == shndx)
1554 // Whether output local symbol count needs updating.
1556 output_local_symbol_count_needs_update() const
1557 { return this->output_local_symbol_count_needs_update_; }
1559 // Set output_local_symbol_count_needs_update flag to be true.
1561 set_output_local_symbol_count_needs_update()
1562 { this->output_local_symbol_count_needs_update_ = true; }
1564 // Update output local symbol count at the end of relaxation.
1566 update_output_local_symbol_count();
1569 // Post constructor setup.
1573 // Call parent's setup method.
1574 Sized_relobj<32, big_endian>::do_setup();
1576 // Initialize look-up tables.
1577 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
1578 this->stub_tables_.swap(empty_stub_table_list);
1581 // Count the local symbols.
1583 do_count_local_symbols(Stringpool_template<char>*,
1584 Stringpool_template<char>*);
1587 do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
1588 const unsigned char* pshdrs,
1589 typename Sized_relobj<32, big_endian>::Views* pivews);
1591 // Read the symbol information.
1593 do_read_symbols(Read_symbols_data* sd);
1595 // Process relocs for garbage collection.
1597 do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
1601 // Whether a section needs to be scanned for relocation stubs.
1603 section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1604 const Relobj::Output_sections&,
1605 const Symbol_table *, const unsigned char*);
1607 // Whether a section is a scannable text section.
1609 section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
1610 const Output_section*, const Symbol_table *);
1612 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1614 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1615 unsigned int, Output_section*,
1616 const Symbol_table *);
1618 // Scan a section for the Cortex-A8 erratum.
1620 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
1621 unsigned int, Output_section*,
1622 Target_arm<big_endian>*);
1624 // Find the linked text section of an EXIDX section by looking at the
1625 // first reloction of the EXIDX section. PSHDR points to the section
1626 // headers of a relocation section and PSYMS points to the local symbols.
1627 // PSHNDX points to a location storing the text section index if found.
1628 // Return whether we can find the linked section.
1630 find_linked_text_section(const unsigned char* pshdr,
1631 const unsigned char* psyms, unsigned int* pshndx);
1634 // Make a new Arm_exidx_input_section object for EXIDX section with
1635 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1636 // index of the linked text section.
1638 make_exidx_input_section(unsigned int shndx,
1639 const elfcpp::Shdr<32, big_endian>& shdr,
1640 unsigned int text_shndx);
1642 // Return the output address of either a plain input section or a
1643 // relaxed input section. SHNDX is the section index.
1645 simple_input_section_output_address(unsigned int, Output_section*);
1647 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
1648 typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
1651 // List of stub tables.
1652 Stub_table_list stub_tables_;
1653 // Bit vector to tell if a local symbol is a thumb function or not.
1654 // This is only valid after do_count_local_symbol is called.
1655 std::vector<bool> local_symbol_is_thumb_function_;
1656 // processor-specific flags in ELF file header.
1657 elfcpp::Elf_Word processor_specific_flags_;
1658 // Object attributes if there is an .ARM.attributes section or NULL.
1659 Attributes_section_data* attributes_section_data_;
1660 // Mapping symbols information.
1661 Mapping_symbols_info mapping_symbols_info_;
1662 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1663 std::vector<bool>* section_has_cortex_a8_workaround_;
1664 // Map a text section to its associated .ARM.exidx section, if there is one.
1665 Exidx_section_map exidx_section_map_;
1666 // Whether output local symbol count needs updating.
1667 bool output_local_symbol_count_needs_update_;
1670 // Arm_dynobj class.
1672 template<bool big_endian>
1673 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1676 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1677 const elfcpp::Ehdr<32, big_endian>& ehdr)
1678 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1679 processor_specific_flags_(0), attributes_section_data_(NULL)
1683 { delete this->attributes_section_data_; }
1685 // Downcast a base pointer to an Arm_relobj pointer. This is
1686 // not type-safe but we only use Arm_relobj not the base class.
1687 static Arm_dynobj<big_endian>*
1688 as_arm_dynobj(Dynobj* dynobj)
1689 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1691 // Processor-specific flags in ELF file header. This is valid only after
1694 processor_specific_flags() const
1695 { return this->processor_specific_flags_; }
1697 // Attributes section data.
1698 const Attributes_section_data*
1699 attributes_section_data() const
1700 { return this->attributes_section_data_; }
1703 // Read the symbol information.
1705 do_read_symbols(Read_symbols_data* sd);
1708 // processor-specific flags in ELF file header.
1709 elfcpp::Elf_Word processor_specific_flags_;
1710 // Object attributes if there is an .ARM.attributes section or NULL.
1711 Attributes_section_data* attributes_section_data_;
1714 // Functor to read reloc addends during stub generation.
1716 template<int sh_type, bool big_endian>
1717 struct Stub_addend_reader
1719 // Return the addend for a relocation of a particular type. Depending
1720 // on whether this is a REL or RELA relocation, read the addend from a
1721 // view or from a Reloc object.
1722 elfcpp::Elf_types<32>::Elf_Swxword
1724 unsigned int /* r_type */,
1725 const unsigned char* /* view */,
1726 const typename Reloc_types<sh_type,
1727 32, big_endian>::Reloc& /* reloc */) const;
1730 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1732 template<bool big_endian>
1733 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1735 elfcpp::Elf_types<32>::Elf_Swxword
1738 const unsigned char*,
1739 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1742 // Specialized Stub_addend_reader for RELA type relocation sections.
1743 // We currently do not handle RELA type relocation sections but it is trivial
1744 // to implement the addend reader. This is provided for completeness and to
1745 // make it easier to add support for RELA relocation sections in the future.
1747 template<bool big_endian>
1748 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1750 elfcpp::Elf_types<32>::Elf_Swxword
1753 const unsigned char*,
1754 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1755 big_endian>::Reloc& reloc) const
1756 { return reloc.get_r_addend(); }
1759 // Cortex_a8_reloc class. We keep record of relocation that may need
1760 // the Cortex-A8 erratum workaround.
1762 class Cortex_a8_reloc
1765 Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
1766 Arm_address destination)
1767 : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
1773 // Accessors: This is a read-only class.
1775 // Return the relocation stub associated with this relocation if there is
1779 { return this->reloc_stub_; }
1781 // Return the relocation type.
1784 { return this->r_type_; }
1786 // Return the destination address of the relocation. LSB stores the THUMB
1790 { return this->destination_; }
1793 // Associated relocation stub if there is one, or NULL.
1794 const Reloc_stub* reloc_stub_;
1796 unsigned int r_type_;
1797 // Destination address of this relocation. LSB is used to distinguish
1799 Arm_address destination_;
1802 // Arm_output_data_got class. We derive this from Output_data_got to add
1803 // extra methods to handle TLS relocations in a static link.
1805 template<bool big_endian>
1806 class Arm_output_data_got : public Output_data_got<32, big_endian>
1809 Arm_output_data_got(Symbol_table* symtab, Layout* layout)
1810 : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
1813 // Add a static entry for the GOT entry at OFFSET. GSYM is a global
1814 // symbol and R_TYPE is the code of a dynamic relocation that needs to be
1815 // applied in a static link.
1817 add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1818 { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
1820 // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
1821 // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
1822 // relocation that needs to be applied in a static link.
1824 add_static_reloc(unsigned int got_offset, unsigned int r_type,
1825 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1827 this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
1831 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
1832 // The first one is initialized to be 1, which is the module index for
1833 // the main executable and the second one 0. A reloc of the type
1834 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
1835 // be applied by gold. GSYM is a global symbol.
1837 add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
1839 // Same as the above but for a local symbol in OBJECT with INDEX.
1841 add_tls_gd32_with_static_reloc(unsigned int got_type,
1842 Sized_relobj<32, big_endian>* object,
1843 unsigned int index);
1846 // Write out the GOT table.
1848 do_write(Output_file*);
1851 // This class represent dynamic relocations that need to be applied by
1852 // gold because we are using TLS relocations in a static link.
1856 Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1857 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
1858 { this->u_.global.symbol = gsym; }
1860 Static_reloc(unsigned int got_offset, unsigned int r_type,
1861 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1862 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
1864 this->u_.local.relobj = relobj;
1865 this->u_.local.index = index;
1868 // Return the GOT offset.
1871 { return this->got_offset_; }
1876 { return this->r_type_; }
1878 // Whether the symbol is global or not.
1880 symbol_is_global() const
1881 { return this->symbol_is_global_; }
1883 // For a relocation against a global symbol, the global symbol.
1887 gold_assert(this->symbol_is_global_);
1888 return this->u_.global.symbol;
1891 // For a relocation against a local symbol, the defining object.
1892 Sized_relobj<32, big_endian>*
1895 gold_assert(!this->symbol_is_global_);
1896 return this->u_.local.relobj;
1899 // For a relocation against a local symbol, the local symbol index.
1903 gold_assert(!this->symbol_is_global_);
1904 return this->u_.local.index;
1908 // GOT offset of the entry to which this relocation is applied.
1909 unsigned int got_offset_;
1910 // Type of relocation.
1911 unsigned int r_type_;
1912 // Whether this relocation is against a global symbol.
1913 bool symbol_is_global_;
1914 // A global or local symbol.
1919 // For a global symbol, the symbol itself.
1924 // For a local symbol, the object defining object.
1925 Sized_relobj<32, big_endian>* relobj;
1926 // For a local symbol, the symbol index.
1932 // Symbol table of the output object.
1933 Symbol_table* symbol_table_;
1934 // Layout of the output object.
1936 // Static relocs to be applied to the GOT.
1937 std::vector<Static_reloc> static_relocs_;
1940 // Utilities for manipulating integers of up to 32-bits
1944 // Sign extend an n-bit unsigned integer stored in an uint32_t into
1945 // an int32_t. NO_BITS must be between 1 to 32.
1946 template<int no_bits>
1947 static inline int32_t
1948 sign_extend(uint32_t bits)
1950 gold_assert(no_bits >= 0 && no_bits <= 32);
1952 return static_cast<int32_t>(bits);
1953 uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
1955 uint32_t top_bit = 1U << (no_bits - 1);
1956 int32_t as_signed = static_cast<int32_t>(bits);
1957 return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
1960 // Detects overflow of an NO_BITS integer stored in a uint32_t.
1961 template<int no_bits>
1963 has_overflow(uint32_t bits)
1965 gold_assert(no_bits >= 0 && no_bits <= 32);
1968 int32_t max = (1 << (no_bits - 1)) - 1;
1969 int32_t min = -(1 << (no_bits - 1));
1970 int32_t as_signed = static_cast<int32_t>(bits);
1971 return as_signed > max || as_signed < min;
1974 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
1975 // fits in the given number of bits as either a signed or unsigned value.
1976 // For example, has_signed_unsigned_overflow<8> would check
1977 // -128 <= bits <= 255
1978 template<int no_bits>
1980 has_signed_unsigned_overflow(uint32_t bits)
1982 gold_assert(no_bits >= 2 && no_bits <= 32);
1985 int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
1986 int32_t min = -(1 << (no_bits - 1));
1987 int32_t as_signed = static_cast<int32_t>(bits);
1988 return as_signed > max || as_signed < min;
1991 // Select bits from A and B using bits in MASK. For each n in [0..31],
1992 // the n-th bit in the result is chosen from the n-th bits of A and B.
1993 // A zero selects A and a one selects B.
1994 static inline uint32_t
1995 bit_select(uint32_t a, uint32_t b, uint32_t mask)
1996 { return (a & ~mask) | (b & mask); }
1999 template<bool big_endian>
2000 class Target_arm : public Sized_target<32, big_endian>
2003 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
2006 // When were are relocating a stub, we pass this as the relocation number.
2007 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
2010 : Sized_target<32, big_endian>(&arm_info),
2011 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
2012 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
2013 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
2014 stub_tables_(), stub_factory_(Stub_factory::get_instance()),
2015 may_use_blx_(false), should_force_pic_veneer_(false),
2016 arm_input_section_map_(), attributes_section_data_(NULL),
2017 fix_cortex_a8_(false), cortex_a8_relocs_info_()
2020 // Whether we can use BLX.
2023 { return this->may_use_blx_; }
2025 // Set use-BLX flag.
2027 set_may_use_blx(bool value)
2028 { this->may_use_blx_ = value; }
2030 // Whether we force PCI branch veneers.
2032 should_force_pic_veneer() const
2033 { return this->should_force_pic_veneer_; }
2035 // Set PIC veneer flag.
2037 set_should_force_pic_veneer(bool value)
2038 { this->should_force_pic_veneer_ = value; }
2040 // Whether we use THUMB-2 instructions.
2042 using_thumb2() const
2044 Object_attribute* attr =
2045 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2046 int arch = attr->int_value();
2047 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
2050 // Whether we use THUMB/THUMB-2 instructions only.
2052 using_thumb_only() const
2054 Object_attribute* attr =
2055 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2056 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2057 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2059 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2060 return attr->int_value() == 'M';
2063 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2065 may_use_arm_nop() const
2067 Object_attribute* attr =
2068 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2069 int arch = attr->int_value();
2070 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2071 || arch == elfcpp::TAG_CPU_ARCH_V6K
2072 || arch == elfcpp::TAG_CPU_ARCH_V7
2073 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2076 // Whether we have THUMB-2 NOP.W instruction.
2078 may_use_thumb2_nop() const
2080 Object_attribute* attr =
2081 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2082 int arch = attr->int_value();
2083 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2084 || arch == elfcpp::TAG_CPU_ARCH_V7
2085 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2088 // Process the relocations to determine unreferenced sections for
2089 // garbage collection.
2091 gc_process_relocs(Symbol_table* symtab,
2093 Sized_relobj<32, big_endian>* object,
2094 unsigned int data_shndx,
2095 unsigned int sh_type,
2096 const unsigned char* prelocs,
2098 Output_section* output_section,
2099 bool needs_special_offset_handling,
2100 size_t local_symbol_count,
2101 const unsigned char* plocal_symbols);
2103 // Scan the relocations to look for symbol adjustments.
2105 scan_relocs(Symbol_table* symtab,
2107 Sized_relobj<32, big_endian>* object,
2108 unsigned int data_shndx,
2109 unsigned int sh_type,
2110 const unsigned char* prelocs,
2112 Output_section* output_section,
2113 bool needs_special_offset_handling,
2114 size_t local_symbol_count,
2115 const unsigned char* plocal_symbols);
2117 // Finalize the sections.
2119 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2121 // Return the value to use for a dynamic symbol which requires special
2124 do_dynsym_value(const Symbol*) const;
2126 // Relocate a section.
2128 relocate_section(const Relocate_info<32, big_endian>*,
2129 unsigned int sh_type,
2130 const unsigned char* prelocs,
2132 Output_section* output_section,
2133 bool needs_special_offset_handling,
2134 unsigned char* view,
2135 Arm_address view_address,
2136 section_size_type view_size,
2137 const Reloc_symbol_changes*);
2139 // Scan the relocs during a relocatable link.
2141 scan_relocatable_relocs(Symbol_table* symtab,
2143 Sized_relobj<32, big_endian>* object,
2144 unsigned int data_shndx,
2145 unsigned int sh_type,
2146 const unsigned char* prelocs,
2148 Output_section* output_section,
2149 bool needs_special_offset_handling,
2150 size_t local_symbol_count,
2151 const unsigned char* plocal_symbols,
2152 Relocatable_relocs*);
2154 // Relocate a section during a relocatable link.
2156 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
2157 unsigned int sh_type,
2158 const unsigned char* prelocs,
2160 Output_section* output_section,
2161 off_t offset_in_output_section,
2162 const Relocatable_relocs*,
2163 unsigned char* view,
2164 Arm_address view_address,
2165 section_size_type view_size,
2166 unsigned char* reloc_view,
2167 section_size_type reloc_view_size);
2169 // Return whether SYM is defined by the ABI.
2171 do_is_defined_by_abi(Symbol* sym) const
2172 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2174 // Return whether there is a GOT section.
2176 has_got_section() const
2177 { return this->got_ != NULL; }
2179 // Return the size of the GOT section.
2183 gold_assert(this->got_ != NULL);
2184 return this->got_->data_size();
2187 // Map platform-specific reloc types
2189 get_real_reloc_type (unsigned int r_type);
2192 // Methods to support stub-generations.
2195 // Return the stub factory
2197 stub_factory() const
2198 { return this->stub_factory_; }
2200 // Make a new Arm_input_section object.
2201 Arm_input_section<big_endian>*
2202 new_arm_input_section(Relobj*, unsigned int);
2204 // Find the Arm_input_section object corresponding to the SHNDX-th input
2205 // section of RELOBJ.
2206 Arm_input_section<big_endian>*
2207 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2209 // Make a new Stub_table
2210 Stub_table<big_endian>*
2211 new_stub_table(Arm_input_section<big_endian>*);
2213 // Scan a section for stub generation.
2215 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2216 const unsigned char*, size_t, Output_section*,
2217 bool, const unsigned char*, Arm_address,
2222 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2223 Output_section*, unsigned char*, Arm_address,
2226 // Get the default ARM target.
2227 static Target_arm<big_endian>*
2230 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2231 && parameters->target().is_big_endian() == big_endian);
2232 return static_cast<Target_arm<big_endian>*>(
2233 parameters->sized_target<32, big_endian>());
2236 // Whether NAME belongs to a mapping symbol.
2238 is_mapping_symbol_name(const char* name)
2242 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2243 && (name[2] == '\0' || name[2] == '.'));
2246 // Whether we work around the Cortex-A8 erratum.
2248 fix_cortex_a8() const
2249 { return this->fix_cortex_a8_; }
2251 // Whether we fix R_ARM_V4BX relocation.
2253 // 1 - replace with MOV instruction (armv4 target)
2254 // 2 - make interworking veneer (>= armv4t targets only)
2255 General_options::Fix_v4bx
2257 { return parameters->options().fix_v4bx(); }
2259 // Scan a span of THUMB code section for Cortex-A8 erratum.
2261 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2262 section_size_type, section_size_type,
2263 const unsigned char*, Arm_address);
2265 // Apply Cortex-A8 workaround to a branch.
2267 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2268 unsigned char*, Arm_address);
2271 // Make an ELF object.
2273 do_make_elf_object(const std::string&, Input_file*, off_t,
2274 const elfcpp::Ehdr<32, big_endian>& ehdr);
2277 do_make_elf_object(const std::string&, Input_file*, off_t,
2278 const elfcpp::Ehdr<32, !big_endian>&)
2279 { gold_unreachable(); }
2282 do_make_elf_object(const std::string&, Input_file*, off_t,
2283 const elfcpp::Ehdr<64, false>&)
2284 { gold_unreachable(); }
2287 do_make_elf_object(const std::string&, Input_file*, off_t,
2288 const elfcpp::Ehdr<64, true>&)
2289 { gold_unreachable(); }
2291 // Make an output section.
2293 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2294 elfcpp::Elf_Xword flags)
2295 { return new Arm_output_section<big_endian>(name, type, flags); }
2298 do_adjust_elf_header(unsigned char* view, int len) const;
2300 // We only need to generate stubs, and hence perform relaxation if we are
2301 // not doing relocatable linking.
2303 do_may_relax() const
2304 { return !parameters->options().relocatable(); }
2307 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
2309 // Determine whether an object attribute tag takes an integer, a
2312 do_attribute_arg_type(int tag) const;
2314 // Reorder tags during output.
2316 do_attributes_order(int num) const;
2318 // This is called when the target is selected as the default.
2320 do_select_as_default_target()
2322 // No locking is required since there should only be one default target.
2323 // We cannot have both the big-endian and little-endian ARM targets
2325 gold_assert(arm_reloc_property_table == NULL);
2326 arm_reloc_property_table = new Arm_reloc_property_table();
2330 // The class which scans relocations.
2335 : issued_non_pic_error_(false)
2339 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2340 Sized_relobj<32, big_endian>* object,
2341 unsigned int data_shndx,
2342 Output_section* output_section,
2343 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2344 const elfcpp::Sym<32, big_endian>& lsym);
2347 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2348 Sized_relobj<32, big_endian>* object,
2349 unsigned int data_shndx,
2350 Output_section* output_section,
2351 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2355 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2356 Sized_relobj<32, big_endian>* ,
2359 const elfcpp::Rel<32, big_endian>& ,
2361 const elfcpp::Sym<32, big_endian>&)
2365 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2366 Sized_relobj<32, big_endian>* ,
2369 const elfcpp::Rel<32, big_endian>& ,
2370 unsigned int , Symbol*)
2375 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
2376 unsigned int r_type);
2379 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
2380 unsigned int r_type, Symbol*);
2383 check_non_pic(Relobj*, unsigned int r_type);
2385 // Almost identical to Symbol::needs_plt_entry except that it also
2386 // handles STT_ARM_TFUNC.
2388 symbol_needs_plt_entry(const Symbol* sym)
2390 // An undefined symbol from an executable does not need a PLT entry.
2391 if (sym->is_undefined() && !parameters->options().shared())
2394 return (!parameters->doing_static_link()
2395 && (sym->type() == elfcpp::STT_FUNC
2396 || sym->type() == elfcpp::STT_ARM_TFUNC)
2397 && (sym->is_from_dynobj()
2398 || sym->is_undefined()
2399 || sym->is_preemptible()));
2402 // Whether we have issued an error about a non-PIC compilation.
2403 bool issued_non_pic_error_;
2406 // The class which implements relocation.
2416 // Return whether the static relocation needs to be applied.
2418 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2421 Output_section* output_section);
2423 // Do a relocation. Return false if the caller should not issue
2424 // any warnings about this relocation.
2426 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2427 Output_section*, size_t relnum,
2428 const elfcpp::Rel<32, big_endian>&,
2429 unsigned int r_type, const Sized_symbol<32>*,
2430 const Symbol_value<32>*,
2431 unsigned char*, Arm_address,
2434 // Return whether we want to pass flag NON_PIC_REF for this
2435 // reloc. This means the relocation type accesses a symbol not via
2438 reloc_is_non_pic (unsigned int r_type)
2442 // These relocation types reference GOT or PLT entries explicitly.
2443 case elfcpp::R_ARM_GOT_BREL:
2444 case elfcpp::R_ARM_GOT_ABS:
2445 case elfcpp::R_ARM_GOT_PREL:
2446 case elfcpp::R_ARM_GOT_BREL12:
2447 case elfcpp::R_ARM_PLT32_ABS:
2448 case elfcpp::R_ARM_TLS_GD32:
2449 case elfcpp::R_ARM_TLS_LDM32:
2450 case elfcpp::R_ARM_TLS_IE32:
2451 case elfcpp::R_ARM_TLS_IE12GP:
2453 // These relocate types may use PLT entries.
2454 case elfcpp::R_ARM_CALL:
2455 case elfcpp::R_ARM_THM_CALL:
2456 case elfcpp::R_ARM_JUMP24:
2457 case elfcpp::R_ARM_THM_JUMP24:
2458 case elfcpp::R_ARM_THM_JUMP19:
2459 case elfcpp::R_ARM_PLT32:
2460 case elfcpp::R_ARM_THM_XPC22:
2461 case elfcpp::R_ARM_PREL31:
2462 case elfcpp::R_ARM_SBREL31:
2471 // Do a TLS relocation.
2472 inline typename Arm_relocate_functions<big_endian>::Status
2473 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2474 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2475 const Sized_symbol<32>*, const Symbol_value<32>*,
2476 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2481 // A class which returns the size required for a relocation type,
2482 // used while scanning relocs during a relocatable link.
2483 class Relocatable_size_for_reloc
2487 get_size_for_reloc(unsigned int, Relobj*);
2490 // Adjust TLS relocation type based on the options and whether this
2491 // is a local symbol.
2492 static tls::Tls_optimization
2493 optimize_tls_reloc(bool is_final, int r_type);
2495 // Get the GOT section, creating it if necessary.
2496 Arm_output_data_got<big_endian>*
2497 got_section(Symbol_table*, Layout*);
2499 // Get the GOT PLT section.
2501 got_plt_section() const
2503 gold_assert(this->got_plt_ != NULL);
2504 return this->got_plt_;
2507 // Create a PLT entry for a global symbol.
2509 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2511 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2513 define_tls_base_symbol(Symbol_table*, Layout*);
2515 // Create a GOT entry for the TLS module index.
2517 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2518 Sized_relobj<32, big_endian>* object);
2520 // Get the PLT section.
2521 const Output_data_plt_arm<big_endian>*
2524 gold_assert(this->plt_ != NULL);
2528 // Get the dynamic reloc section, creating it if necessary.
2530 rel_dyn_section(Layout*);
2532 // Get the section to use for TLS_DESC relocations.
2534 rel_tls_desc_section(Layout*) const;
2536 // Return true if the symbol may need a COPY relocation.
2537 // References from an executable object to non-function symbols
2538 // defined in a dynamic object may need a COPY relocation.
2540 may_need_copy_reloc(Symbol* gsym)
2542 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2543 && gsym->may_need_copy_reloc());
2546 // Add a potential copy relocation.
2548 copy_reloc(Symbol_table* symtab, Layout* layout,
2549 Sized_relobj<32, big_endian>* object,
2550 unsigned int shndx, Output_section* output_section,
2551 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2553 this->copy_relocs_.copy_reloc(symtab, layout,
2554 symtab->get_sized_symbol<32>(sym),
2555 object, shndx, output_section, reloc,
2556 this->rel_dyn_section(layout));
2559 // Whether two EABI versions are compatible.
2561 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2563 // Merge processor-specific flags from input object and those in the ELF
2564 // header of the output.
2566 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2568 // Get the secondary compatible architecture.
2570 get_secondary_compatible_arch(const Attributes_section_data*);
2572 // Set the secondary compatible architecture.
2574 set_secondary_compatible_arch(Attributes_section_data*, int);
2577 tag_cpu_arch_combine(const char*, int, int*, int, int);
2579 // Helper to print AEABI enum tag value.
2581 aeabi_enum_name(unsigned int);
2583 // Return string value for TAG_CPU_name.
2585 tag_cpu_name_value(unsigned int);
2587 // Merge object attributes from input object and those in the output.
2589 merge_object_attributes(const char*, const Attributes_section_data*);
2591 // Helper to get an AEABI object attribute
2593 get_aeabi_object_attribute(int tag) const
2595 Attributes_section_data* pasd = this->attributes_section_data_;
2596 gold_assert(pasd != NULL);
2597 Object_attribute* attr =
2598 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2599 gold_assert(attr != NULL);
2604 // Methods to support stub-generations.
2607 // Group input sections for stub generation.
2609 group_sections(Layout*, section_size_type, bool);
2611 // Scan a relocation for stub generation.
2613 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2614 const Sized_symbol<32>*, unsigned int,
2615 const Symbol_value<32>*,
2616 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2618 // Scan a relocation section for stub.
2619 template<int sh_type>
2621 scan_reloc_section_for_stubs(
2622 const Relocate_info<32, big_endian>* relinfo,
2623 const unsigned char* prelocs,
2625 Output_section* output_section,
2626 bool needs_special_offset_handling,
2627 const unsigned char* view,
2628 elfcpp::Elf_types<32>::Elf_Addr view_address,
2631 // Fix .ARM.exidx section coverage.
2633 fix_exidx_coverage(Layout*, Arm_output_section<big_endian>*, Symbol_table*);
2635 // Functors for STL set.
2636 struct output_section_address_less_than
2639 operator()(const Output_section* s1, const Output_section* s2) const
2640 { return s1->address() < s2->address(); }
2643 // Information about this specific target which we pass to the
2644 // general Target structure.
2645 static const Target::Target_info arm_info;
2647 // The types of GOT entries needed for this platform.
2650 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2651 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2652 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2653 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2654 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2657 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2659 // Map input section to Arm_input_section.
2660 typedef Unordered_map<Section_id,
2661 Arm_input_section<big_endian>*,
2663 Arm_input_section_map;
2665 // Map output addresses to relocs for Cortex-A8 erratum.
2666 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2667 Cortex_a8_relocs_info;
2670 Arm_output_data_got<big_endian>* got_;
2672 Output_data_plt_arm<big_endian>* plt_;
2673 // The GOT PLT section.
2674 Output_data_space* got_plt_;
2675 // The dynamic reloc section.
2676 Reloc_section* rel_dyn_;
2677 // Relocs saved to avoid a COPY reloc.
2678 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2679 // Space for variables copied with a COPY reloc.
2680 Output_data_space* dynbss_;
2681 // Offset of the GOT entry for the TLS module index.
2682 unsigned int got_mod_index_offset_;
2683 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2684 bool tls_base_symbol_defined_;
2685 // Vector of Stub_tables created.
2686 Stub_table_list stub_tables_;
2688 const Stub_factory &stub_factory_;
2689 // Whether we can use BLX.
2691 // Whether we force PIC branch veneers.
2692 bool should_force_pic_veneer_;
2693 // Map for locating Arm_input_sections.
2694 Arm_input_section_map arm_input_section_map_;
2695 // Attributes section data in output.
2696 Attributes_section_data* attributes_section_data_;
2697 // Whether we want to fix code for Cortex-A8 erratum.
2698 bool fix_cortex_a8_;
2699 // Map addresses to relocs for Cortex-A8 erratum.
2700 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2703 template<bool big_endian>
2704 const Target::Target_info Target_arm<big_endian>::arm_info =
2707 big_endian, // is_big_endian
2708 elfcpp::EM_ARM, // machine_code
2709 false, // has_make_symbol
2710 false, // has_resolve
2711 false, // has_code_fill
2712 true, // is_default_stack_executable
2714 "/usr/lib/libc.so.1", // dynamic_linker
2715 0x8000, // default_text_segment_address
2716 0x1000, // abi_pagesize (overridable by -z max-page-size)
2717 0x1000, // common_pagesize (overridable by -z common-page-size)
2718 elfcpp::SHN_UNDEF, // small_common_shndx
2719 elfcpp::SHN_UNDEF, // large_common_shndx
2720 0, // small_common_section_flags
2721 0, // large_common_section_flags
2722 ".ARM.attributes", // attributes_section
2723 "aeabi" // attributes_vendor
2726 // Arm relocate functions class
2729 template<bool big_endian>
2730 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2735 STATUS_OKAY, // No error during relocation.
2736 STATUS_OVERFLOW, // Relocation oveflow.
2737 STATUS_BAD_RELOC // Relocation cannot be applied.
2741 typedef Relocate_functions<32, big_endian> Base;
2742 typedef Arm_relocate_functions<big_endian> This;
2744 // Encoding of imm16 argument for movt and movw ARM instructions
2747 // imm16 := imm4 | imm12
2749 // 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
2750 // +-------+---------------+-------+-------+-----------------------+
2751 // | | |imm4 | |imm12 |
2752 // +-------+---------------+-------+-------+-----------------------+
2754 // Extract the relocation addend from VAL based on the ARM
2755 // instruction encoding described above.
2756 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2757 extract_arm_movw_movt_addend(
2758 typename elfcpp::Swap<32, big_endian>::Valtype val)
2760 // According to the Elf ABI for ARM Architecture the immediate
2761 // field is sign-extended to form the addend.
2762 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
2765 // Insert X into VAL based on the ARM instruction encoding described
2767 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2768 insert_val_arm_movw_movt(
2769 typename elfcpp::Swap<32, big_endian>::Valtype val,
2770 typename elfcpp::Swap<32, big_endian>::Valtype x)
2774 val |= (x & 0xf000) << 4;
2778 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2781 // imm16 := imm4 | i | imm3 | imm8
2783 // 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
2784 // +---------+-+-----------+-------++-+-----+-------+---------------+
2785 // | |i| |imm4 || |imm3 | |imm8 |
2786 // +---------+-+-----------+-------++-+-----+-------+---------------+
2788 // Extract the relocation addend from VAL based on the Thumb2
2789 // instruction encoding described above.
2790 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2791 extract_thumb_movw_movt_addend(
2792 typename elfcpp::Swap<32, big_endian>::Valtype val)
2794 // According to the Elf ABI for ARM Architecture the immediate
2795 // field is sign-extended to form the addend.
2796 return utils::sign_extend<16>(((val >> 4) & 0xf000)
2797 | ((val >> 15) & 0x0800)
2798 | ((val >> 4) & 0x0700)
2802 // Insert X into VAL based on the Thumb2 instruction encoding
2804 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2805 insert_val_thumb_movw_movt(
2806 typename elfcpp::Swap<32, big_endian>::Valtype val,
2807 typename elfcpp::Swap<32, big_endian>::Valtype x)
2810 val |= (x & 0xf000) << 4;
2811 val |= (x & 0x0800) << 15;
2812 val |= (x & 0x0700) << 4;
2813 val |= (x & 0x00ff);
2817 // Calculate the smallest constant Kn for the specified residual.
2818 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2820 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
2826 // Determine the most significant bit in the residual and
2827 // align the resulting value to a 2-bit boundary.
2828 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
2830 // The desired shift is now (msb - 6), or zero, whichever
2832 return (((msb - 6) < 0) ? 0 : (msb - 6));
2835 // Calculate the final residual for the specified group index.
2836 // If the passed group index is less than zero, the method will return
2837 // the value of the specified residual without any change.
2838 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2839 static typename elfcpp::Swap<32, big_endian>::Valtype
2840 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2843 for (int n = 0; n <= group; n++)
2845 // Calculate which part of the value to mask.
2846 uint32_t shift = calc_grp_kn(residual);
2847 // Calculate the residual for the next time around.
2848 residual &= ~(residual & (0xff << shift));
2854 // Calculate the value of Gn for the specified group index.
2855 // We return it in the form of an encoded constant-and-rotation.
2856 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2857 static typename elfcpp::Swap<32, big_endian>::Valtype
2858 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2861 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
2864 for (int n = 0; n <= group; n++)
2866 // Calculate which part of the value to mask.
2867 shift = calc_grp_kn(residual);
2868 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
2869 gn = residual & (0xff << shift);
2870 // Calculate the residual for the next time around.
2873 // Return Gn in the form of an encoded constant-and-rotation.
2874 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
2878 // Handle ARM long branches.
2879 static typename This::Status
2880 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2881 unsigned char *, const Sized_symbol<32>*,
2882 const Arm_relobj<big_endian>*, unsigned int,
2883 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2885 // Handle THUMB long branches.
2886 static typename This::Status
2887 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2888 unsigned char *, const Sized_symbol<32>*,
2889 const Arm_relobj<big_endian>*, unsigned int,
2890 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2893 // Return the branch offset of a 32-bit THUMB branch.
2894 static inline int32_t
2895 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2897 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
2898 // involving the J1 and J2 bits.
2899 uint32_t s = (upper_insn & (1U << 10)) >> 10;
2900 uint32_t upper = upper_insn & 0x3ffU;
2901 uint32_t lower = lower_insn & 0x7ffU;
2902 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
2903 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
2904 uint32_t i1 = j1 ^ s ? 0 : 1;
2905 uint32_t i2 = j2 ^ s ? 0 : 1;
2907 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
2908 | (upper << 12) | (lower << 1));
2911 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
2912 // UPPER_INSN is the original upper instruction of the branch. Caller is
2913 // responsible for overflow checking and BLX offset adjustment.
2914 static inline uint16_t
2915 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
2917 uint32_t s = offset < 0 ? 1 : 0;
2918 uint32_t bits = static_cast<uint32_t>(offset);
2919 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
2922 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
2923 // LOWER_INSN is the original lower instruction of the branch. Caller is
2924 // responsible for overflow checking and BLX offset adjustment.
2925 static inline uint16_t
2926 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
2928 uint32_t s = offset < 0 ? 1 : 0;
2929 uint32_t bits = static_cast<uint32_t>(offset);
2930 return ((lower_insn & ~0x2fffU)
2931 | ((((bits >> 23) & 1) ^ !s) << 13)
2932 | ((((bits >> 22) & 1) ^ !s) << 11)
2933 | ((bits >> 1) & 0x7ffU));
2936 // Return the branch offset of a 32-bit THUMB conditional branch.
2937 static inline int32_t
2938 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2940 uint32_t s = (upper_insn & 0x0400U) >> 10;
2941 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
2942 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
2943 uint32_t lower = (lower_insn & 0x07ffU);
2944 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
2946 return utils::sign_extend<21>((upper << 12) | (lower << 1));
2949 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
2950 // instruction. UPPER_INSN is the original upper instruction of the branch.
2951 // Caller is responsible for overflow checking.
2952 static inline uint16_t
2953 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
2955 uint32_t s = offset < 0 ? 1 : 0;
2956 uint32_t bits = static_cast<uint32_t>(offset);
2957 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
2960 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
2961 // instruction. LOWER_INSN is the original lower instruction of the branch.
2962 // Caller is reponsible for overflow checking.
2963 static inline uint16_t
2964 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
2966 uint32_t bits = static_cast<uint32_t>(offset);
2967 uint32_t j2 = (bits & 0x00080000U) >> 19;
2968 uint32_t j1 = (bits & 0x00040000U) >> 18;
2969 uint32_t lo = (bits & 0x00000ffeU) >> 1;
2971 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
2974 // R_ARM_ABS8: S + A
2975 static inline typename This::Status
2976 abs8(unsigned char *view,
2977 const Sized_relobj<32, big_endian>* object,
2978 const Symbol_value<32>* psymval)
2980 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
2981 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2982 Valtype* wv = reinterpret_cast<Valtype*>(view);
2983 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
2984 Reltype addend = utils::sign_extend<8>(val);
2985 Reltype x = psymval->value(object, addend);
2986 val = utils::bit_select(val, x, 0xffU);
2987 elfcpp::Swap<8, big_endian>::writeval(wv, val);
2989 // R_ARM_ABS8 permits signed or unsigned results.
2990 int signed_x = static_cast<int32_t>(x);
2991 return ((signed_x < -128 || signed_x > 255)
2992 ? This::STATUS_OVERFLOW
2993 : This::STATUS_OKAY);
2996 // R_ARM_THM_ABS5: S + A
2997 static inline typename This::Status
2998 thm_abs5(unsigned char *view,
2999 const Sized_relobj<32, big_endian>* object,
3000 const Symbol_value<32>* psymval)
3002 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3003 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3004 Valtype* wv = reinterpret_cast<Valtype*>(view);
3005 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3006 Reltype addend = (val & 0x7e0U) >> 6;
3007 Reltype x = psymval->value(object, addend);
3008 val = utils::bit_select(val, x << 6, 0x7e0U);
3009 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3011 // R_ARM_ABS16 permits signed or unsigned results.
3012 int signed_x = static_cast<int32_t>(x);
3013 return ((signed_x < -32768 || signed_x > 65535)
3014 ? This::STATUS_OVERFLOW
3015 : This::STATUS_OKAY);
3018 // R_ARM_ABS12: S + A
3019 static inline typename This::Status
3020 abs12(unsigned char *view,
3021 const Sized_relobj<32, big_endian>* object,
3022 const Symbol_value<32>* psymval)
3024 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3025 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3026 Valtype* wv = reinterpret_cast<Valtype*>(view);
3027 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3028 Reltype addend = val & 0x0fffU;
3029 Reltype x = psymval->value(object, addend);
3030 val = utils::bit_select(val, x, 0x0fffU);
3031 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3032 return (utils::has_overflow<12>(x)
3033 ? This::STATUS_OVERFLOW
3034 : This::STATUS_OKAY);
3037 // R_ARM_ABS16: S + A
3038 static inline typename This::Status
3039 abs16(unsigned char *view,
3040 const Sized_relobj<32, big_endian>* object,
3041 const Symbol_value<32>* psymval)
3043 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3044 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3045 Valtype* wv = reinterpret_cast<Valtype*>(view);
3046 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3047 Reltype addend = utils::sign_extend<16>(val);
3048 Reltype x = psymval->value(object, addend);
3049 val = utils::bit_select(val, x, 0xffffU);
3050 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3051 return (utils::has_signed_unsigned_overflow<16>(x)
3052 ? This::STATUS_OVERFLOW
3053 : This::STATUS_OKAY);
3056 // R_ARM_ABS32: (S + A) | T
3057 static inline typename This::Status
3058 abs32(unsigned char *view,
3059 const Sized_relobj<32, big_endian>* object,
3060 const Symbol_value<32>* psymval,
3061 Arm_address thumb_bit)
3063 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3064 Valtype* wv = reinterpret_cast<Valtype*>(view);
3065 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3066 Valtype x = psymval->value(object, addend) | thumb_bit;
3067 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3068 return This::STATUS_OKAY;
3071 // R_ARM_REL32: (S + A) | T - P
3072 static inline typename This::Status
3073 rel32(unsigned char *view,
3074 const Sized_relobj<32, big_endian>* object,
3075 const Symbol_value<32>* psymval,
3076 Arm_address address,
3077 Arm_address thumb_bit)
3079 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3080 Valtype* wv = reinterpret_cast<Valtype*>(view);
3081 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3082 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3083 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3084 return This::STATUS_OKAY;
3087 // R_ARM_THM_JUMP24: (S + A) | T - P
3088 static typename This::Status
3089 thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object,
3090 const Symbol_value<32>* psymval, Arm_address address,
3091 Arm_address thumb_bit);
3093 // R_ARM_THM_JUMP6: S + A – P
3094 static inline typename This::Status
3095 thm_jump6(unsigned char *view,
3096 const Sized_relobj<32, big_endian>* object,
3097 const Symbol_value<32>* psymval,
3098 Arm_address address)
3100 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3101 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3102 Valtype* wv = reinterpret_cast<Valtype*>(view);
3103 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3104 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3105 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3106 Reltype x = (psymval->value(object, addend) - address);
3107 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3108 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3109 // CZB does only forward jumps.
3110 return ((x > 0x007e)
3111 ? This::STATUS_OVERFLOW
3112 : This::STATUS_OKAY);
3115 // R_ARM_THM_JUMP8: S + A – P
3116 static inline typename This::Status
3117 thm_jump8(unsigned char *view,
3118 const Sized_relobj<32, big_endian>* object,
3119 const Symbol_value<32>* psymval,
3120 Arm_address address)
3122 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3123 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3124 Valtype* wv = reinterpret_cast<Valtype*>(view);
3125 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3126 Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
3127 Reltype x = (psymval->value(object, addend) - address);
3128 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
3129 return (utils::has_overflow<8>(x)
3130 ? This::STATUS_OVERFLOW
3131 : This::STATUS_OKAY);
3134 // R_ARM_THM_JUMP11: S + A – P
3135 static inline typename This::Status
3136 thm_jump11(unsigned char *view,
3137 const Sized_relobj<32, big_endian>* object,
3138 const Symbol_value<32>* psymval,
3139 Arm_address address)
3141 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3142 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3143 Valtype* wv = reinterpret_cast<Valtype*>(view);
3144 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3145 Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
3146 Reltype x = (psymval->value(object, addend) - address);
3147 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
3148 return (utils::has_overflow<11>(x)
3149 ? This::STATUS_OVERFLOW
3150 : This::STATUS_OKAY);
3153 // R_ARM_BASE_PREL: B(S) + A - P
3154 static inline typename This::Status
3155 base_prel(unsigned char* view,
3157 Arm_address address)
3159 Base::rel32(view, origin - address);
3163 // R_ARM_BASE_ABS: B(S) + A
3164 static inline typename This::Status
3165 base_abs(unsigned char* view,
3168 Base::rel32(view, origin);
3172 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3173 static inline typename This::Status
3174 got_brel(unsigned char* view,
3175 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3177 Base::rel32(view, got_offset);
3178 return This::STATUS_OKAY;
3181 // R_ARM_GOT_PREL: GOT(S) + A - P
3182 static inline typename This::Status
3183 got_prel(unsigned char *view,
3184 Arm_address got_entry,
3185 Arm_address address)
3187 Base::rel32(view, got_entry - address);
3188 return This::STATUS_OKAY;
3191 // R_ARM_PREL: (S + A) | T - P
3192 static inline typename This::Status
3193 prel31(unsigned char *view,
3194 const Sized_relobj<32, big_endian>* object,
3195 const Symbol_value<32>* psymval,
3196 Arm_address address,
3197 Arm_address thumb_bit)
3199 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3200 Valtype* wv = reinterpret_cast<Valtype*>(view);
3201 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3202 Valtype addend = utils::sign_extend<31>(val);
3203 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3204 val = utils::bit_select(val, x, 0x7fffffffU);
3205 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3206 return (utils::has_overflow<31>(x) ?
3207 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3210 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3211 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3212 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3213 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3214 static inline typename This::Status
3215 movw(unsigned char* view,
3216 const Sized_relobj<32, big_endian>* object,
3217 const Symbol_value<32>* psymval,
3218 Arm_address relative_address_base,
3219 Arm_address thumb_bit,
3220 bool check_overflow)
3222 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3223 Valtype* wv = reinterpret_cast<Valtype*>(view);
3224 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3225 Valtype addend = This::extract_arm_movw_movt_addend(val);
3226 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3227 - relative_address_base);
3228 val = This::insert_val_arm_movw_movt(val, x);
3229 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3230 return ((check_overflow && utils::has_overflow<16>(x))
3231 ? This::STATUS_OVERFLOW
3232 : This::STATUS_OKAY);
3235 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3236 // R_ARM_MOVT_PREL: S + A - P
3237 // R_ARM_MOVT_BREL: S + A - B(S)
3238 static inline typename This::Status
3239 movt(unsigned char* view,
3240 const Sized_relobj<32, big_endian>* object,
3241 const Symbol_value<32>* psymval,
3242 Arm_address relative_address_base)
3244 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3245 Valtype* wv = reinterpret_cast<Valtype*>(view);
3246 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3247 Valtype addend = This::extract_arm_movw_movt_addend(val);
3248 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3249 val = This::insert_val_arm_movw_movt(val, x);
3250 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3251 // FIXME: IHI0044D says that we should check for overflow.
3252 return This::STATUS_OKAY;
3255 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3256 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3257 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3258 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3259 static inline typename This::Status
3260 thm_movw(unsigned char *view,
3261 const Sized_relobj<32, big_endian>* object,
3262 const Symbol_value<32>* psymval,
3263 Arm_address relative_address_base,
3264 Arm_address thumb_bit,
3265 bool check_overflow)
3267 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3268 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3269 Valtype* wv = reinterpret_cast<Valtype*>(view);
3270 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3271 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3272 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3274 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3275 val = This::insert_val_thumb_movw_movt(val, x);
3276 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3277 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3278 return ((check_overflow && utils::has_overflow<16>(x))
3279 ? This::STATUS_OVERFLOW
3280 : This::STATUS_OKAY);
3283 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3284 // R_ARM_THM_MOVT_PREL: S + A - P
3285 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3286 static inline typename This::Status
3287 thm_movt(unsigned char* view,
3288 const Sized_relobj<32, big_endian>* object,
3289 const Symbol_value<32>* psymval,
3290 Arm_address relative_address_base)
3292 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3293 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3294 Valtype* wv = reinterpret_cast<Valtype*>(view);
3295 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3296 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3297 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3298 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3299 val = This::insert_val_thumb_movw_movt(val, x);
3300 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3301 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3302 return This::STATUS_OKAY;
3305 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3306 static inline typename This::Status
3307 thm_alu11(unsigned char* view,
3308 const Sized_relobj<32, big_endian>* object,
3309 const Symbol_value<32>* psymval,
3310 Arm_address address,
3311 Arm_address thumb_bit)
3313 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3314 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3315 Valtype* wv = reinterpret_cast<Valtype*>(view);
3316 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3317 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3319 // 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
3320 // -----------------------------------------------------------------------
3321 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3322 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3323 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3324 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3325 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3326 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3328 // Determine a sign for the addend.
3329 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3330 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3331 // Thumb2 addend encoding:
3332 // imm12 := i | imm3 | imm8
3333 int32_t addend = (insn & 0xff)
3334 | ((insn & 0x00007000) >> 4)
3335 | ((insn & 0x04000000) >> 15);
3336 // Apply a sign to the added.
3339 int32_t x = (psymval->value(object, addend) | thumb_bit)
3340 - (address & 0xfffffffc);
3341 Reltype val = abs(x);
3342 // Mask out the value and a distinct part of the ADD/SUB opcode
3343 // (bits 7:5 of opword).
3344 insn = (insn & 0xfb0f8f00)
3346 | ((val & 0x700) << 4)
3347 | ((val & 0x800) << 15);
3348 // Set the opcode according to whether the value to go in the
3349 // place is negative.
3353 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3354 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3355 return ((val > 0xfff) ?
3356 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3359 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3360 static inline typename This::Status
3361 thm_pc8(unsigned char* view,
3362 const Sized_relobj<32, big_endian>* object,
3363 const Symbol_value<32>* psymval,
3364 Arm_address address)
3366 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3367 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3368 Valtype* wv = reinterpret_cast<Valtype*>(view);
3369 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3370 Reltype addend = ((insn & 0x00ff) << 2);
3371 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3372 Reltype val = abs(x);
3373 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3375 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3376 return ((val > 0x03fc)
3377 ? This::STATUS_OVERFLOW
3378 : This::STATUS_OKAY);
3381 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3382 static inline typename This::Status
3383 thm_pc12(unsigned char* view,
3384 const Sized_relobj<32, big_endian>* object,
3385 const Symbol_value<32>* psymval,
3386 Arm_address address)
3388 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3389 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3390 Valtype* wv = reinterpret_cast<Valtype*>(view);
3391 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3392 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3393 // Determine a sign for the addend (positive if the U bit is 1).
3394 const int sign = (insn & 0x00800000) ? 1 : -1;
3395 int32_t addend = (insn & 0xfff);
3396 // Apply a sign to the added.
3399 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3400 Reltype val = abs(x);
3401 // Mask out and apply the value and the U bit.
3402 insn = (insn & 0xff7ff000) | (val & 0xfff);
3403 // Set the U bit according to whether the value to go in the
3404 // place is positive.
3408 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3409 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3410 return ((val > 0xfff) ?
3411 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3415 static inline typename This::Status
3416 v4bx(const Relocate_info<32, big_endian>* relinfo,
3417 unsigned char *view,
3418 const Arm_relobj<big_endian>* object,
3419 const Arm_address address,
3420 const bool is_interworking)
3423 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3424 Valtype* wv = reinterpret_cast<Valtype*>(view);
3425 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3427 // Ensure that we have a BX instruction.
3428 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3429 const uint32_t reg = (val & 0xf);
3430 if (is_interworking && reg != 0xf)
3432 Stub_table<big_endian>* stub_table =
3433 object->stub_table(relinfo->data_shndx);
3434 gold_assert(stub_table != NULL);
3436 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3437 gold_assert(stub != NULL);
3439 int32_t veneer_address =
3440 stub_table->address() + stub->offset() - 8 - address;
3441 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3442 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3443 // Replace with a branch to veneer (B <addr>)
3444 val = (val & 0xf0000000) | 0x0a000000
3445 | ((veneer_address >> 2) & 0x00ffffff);
3449 // Preserve Rm (lowest four bits) and the condition code
3450 // (highest four bits). Other bits encode MOV PC,Rm.
3451 val = (val & 0xf000000f) | 0x01a0f000;
3453 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3454 return This::STATUS_OKAY;
3457 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3458 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3459 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3460 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3461 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3462 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3463 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3464 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3465 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3466 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3467 static inline typename This::Status
3468 arm_grp_alu(unsigned char* view,
3469 const Sized_relobj<32, big_endian>* object,
3470 const Symbol_value<32>* psymval,
3472 Arm_address address,
3473 Arm_address thumb_bit,
3474 bool check_overflow)
3476 gold_assert(group >= 0 && group < 3);
3477 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3478 Valtype* wv = reinterpret_cast<Valtype*>(view);
3479 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3481 // ALU group relocations are allowed only for the ADD/SUB instructions.
3482 // (0x00800000 - ADD, 0x00400000 - SUB)
3483 const Valtype opcode = insn & 0x01e00000;
3484 if (opcode != 0x00800000 && opcode != 0x00400000)
3485 return This::STATUS_BAD_RELOC;
3487 // Determine a sign for the addend.
3488 const int sign = (opcode == 0x00800000) ? 1 : -1;
3489 // shifter = rotate_imm * 2
3490 const uint32_t shifter = (insn & 0xf00) >> 7;
3491 // Initial addend value.
3492 int32_t addend = insn & 0xff;
3493 // Rotate addend right by shifter.
3494 addend = (addend >> shifter) | (addend << (32 - shifter));
3495 // Apply a sign to the added.
3498 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3499 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3500 // Check for overflow if required
3502 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3503 return This::STATUS_OVERFLOW;
3505 // Mask out the value and the ADD/SUB part of the opcode; take care
3506 // not to destroy the S bit.
3508 // Set the opcode according to whether the value to go in the
3509 // place is negative.
3510 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3511 // Encode the offset (encoded Gn).
3514 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3515 return This::STATUS_OKAY;
3518 // R_ARM_LDR_PC_G0: S + A - P
3519 // R_ARM_LDR_PC_G1: S + A - P
3520 // R_ARM_LDR_PC_G2: S + A - P
3521 // R_ARM_LDR_SB_G0: S + A - B(S)
3522 // R_ARM_LDR_SB_G1: S + A - B(S)
3523 // R_ARM_LDR_SB_G2: S + A - B(S)
3524 static inline typename This::Status
3525 arm_grp_ldr(unsigned char* view,
3526 const Sized_relobj<32, big_endian>* object,
3527 const Symbol_value<32>* psymval,
3529 Arm_address address)
3531 gold_assert(group >= 0 && group < 3);
3532 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3533 Valtype* wv = reinterpret_cast<Valtype*>(view);
3534 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3536 const int sign = (insn & 0x00800000) ? 1 : -1;
3537 int32_t addend = (insn & 0xfff) * sign;
3538 int32_t x = (psymval->value(object, addend) - address);
3539 // Calculate the relevant G(n-1) value to obtain this stage residual.
3541 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3542 if (residual >= 0x1000)
3543 return This::STATUS_OVERFLOW;
3545 // Mask out the value and U bit.
3547 // Set the U bit for non-negative values.
3552 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3553 return This::STATUS_OKAY;
3556 // R_ARM_LDRS_PC_G0: S + A - P
3557 // R_ARM_LDRS_PC_G1: S + A - P
3558 // R_ARM_LDRS_PC_G2: S + A - P
3559 // R_ARM_LDRS_SB_G0: S + A - B(S)
3560 // R_ARM_LDRS_SB_G1: S + A - B(S)
3561 // R_ARM_LDRS_SB_G2: S + A - B(S)
3562 static inline typename This::Status
3563 arm_grp_ldrs(unsigned char* view,
3564 const Sized_relobj<32, big_endian>* object,
3565 const Symbol_value<32>* psymval,
3567 Arm_address address)
3569 gold_assert(group >= 0 && group < 3);
3570 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3571 Valtype* wv = reinterpret_cast<Valtype*>(view);
3572 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3574 const int sign = (insn & 0x00800000) ? 1 : -1;
3575 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3576 int32_t x = (psymval->value(object, addend) - address);
3577 // Calculate the relevant G(n-1) value to obtain this stage residual.
3579 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3580 if (residual >= 0x100)
3581 return This::STATUS_OVERFLOW;
3583 // Mask out the value and U bit.
3585 // Set the U bit for non-negative values.
3588 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3590 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3591 return This::STATUS_OKAY;
3594 // R_ARM_LDC_PC_G0: S + A - P
3595 // R_ARM_LDC_PC_G1: S + A - P
3596 // R_ARM_LDC_PC_G2: S + A - P
3597 // R_ARM_LDC_SB_G0: S + A - B(S)
3598 // R_ARM_LDC_SB_G1: S + A - B(S)
3599 // R_ARM_LDC_SB_G2: S + A - B(S)
3600 static inline typename This::Status
3601 arm_grp_ldc(unsigned char* view,
3602 const Sized_relobj<32, big_endian>* object,
3603 const Symbol_value<32>* psymval,
3605 Arm_address address)
3607 gold_assert(group >= 0 && group < 3);
3608 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3609 Valtype* wv = reinterpret_cast<Valtype*>(view);
3610 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3612 const int sign = (insn & 0x00800000) ? 1 : -1;
3613 int32_t addend = ((insn & 0xff) << 2) * sign;
3614 int32_t x = (psymval->value(object, addend) - address);
3615 // Calculate the relevant G(n-1) value to obtain this stage residual.
3617 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3618 if ((residual & 0x3) != 0 || residual >= 0x400)
3619 return This::STATUS_OVERFLOW;
3621 // Mask out the value and U bit.
3623 // Set the U bit for non-negative values.
3626 insn |= (residual >> 2);
3628 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3629 return This::STATUS_OKAY;
3633 // Relocate ARM long branches. This handles relocation types
3634 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3635 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3636 // undefined and we do not use PLT in this relocation. In such a case,
3637 // the branch is converted into an NOP.
3639 template<bool big_endian>
3640 typename Arm_relocate_functions<big_endian>::Status
3641 Arm_relocate_functions<big_endian>::arm_branch_common(
3642 unsigned int r_type,
3643 const Relocate_info<32, big_endian>* relinfo,
3644 unsigned char *view,
3645 const Sized_symbol<32>* gsym,
3646 const Arm_relobj<big_endian>* object,
3648 const Symbol_value<32>* psymval,
3649 Arm_address address,
3650 Arm_address thumb_bit,
3651 bool is_weakly_undefined_without_plt)
3653 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3654 Valtype* wv = reinterpret_cast<Valtype*>(view);
3655 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3657 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3658 && ((val & 0x0f000000UL) == 0x0a000000UL);
3659 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3660 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3661 && ((val & 0x0f000000UL) == 0x0b000000UL);
3662 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3663 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3665 // Check that the instruction is valid.
3666 if (r_type == elfcpp::R_ARM_CALL)
3668 if (!insn_is_uncond_bl && !insn_is_blx)
3669 return This::STATUS_BAD_RELOC;
3671 else if (r_type == elfcpp::R_ARM_JUMP24)
3673 if (!insn_is_b && !insn_is_cond_bl)
3674 return This::STATUS_BAD_RELOC;
3676 else if (r_type == elfcpp::R_ARM_PLT32)
3678 if (!insn_is_any_branch)
3679 return This::STATUS_BAD_RELOC;
3681 else if (r_type == elfcpp::R_ARM_XPC25)
3683 // FIXME: AAELF document IH0044C does not say much about it other
3684 // than it being obsolete.
3685 if (!insn_is_any_branch)
3686 return This::STATUS_BAD_RELOC;
3691 // A branch to an undefined weak symbol is turned into a jump to
3692 // the next instruction unless a PLT entry will be created.
3693 // Do the same for local undefined symbols.
3694 // The jump to the next instruction is optimized as a NOP depending
3695 // on the architecture.
3696 const Target_arm<big_endian>* arm_target =
3697 Target_arm<big_endian>::default_target();
3698 if (is_weakly_undefined_without_plt)
3700 Valtype cond = val & 0xf0000000U;
3701 if (arm_target->may_use_arm_nop())
3702 val = cond | 0x0320f000;
3704 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3705 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3706 return This::STATUS_OKAY;
3709 Valtype addend = utils::sign_extend<26>(val << 2);
3710 Valtype branch_target = psymval->value(object, addend);
3711 int32_t branch_offset = branch_target - address;
3713 // We need a stub if the branch offset is too large or if we need
3715 bool may_use_blx = arm_target->may_use_blx();
3716 Reloc_stub* stub = NULL;
3717 if (utils::has_overflow<26>(branch_offset)
3718 || ((thumb_bit != 0) && !(may_use_blx && r_type == elfcpp::R_ARM_CALL)))
3720 Valtype unadjusted_branch_target = psymval->value(object, 0);
3722 Stub_type stub_type =
3723 Reloc_stub::stub_type_for_reloc(r_type, address,
3724 unadjusted_branch_target,
3726 if (stub_type != arm_stub_none)
3728 Stub_table<big_endian>* stub_table =
3729 object->stub_table(relinfo->data_shndx);
3730 gold_assert(stub_table != NULL);
3732 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3733 stub = stub_table->find_reloc_stub(stub_key);
3734 gold_assert(stub != NULL);
3735 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3736 branch_target = stub_table->address() + stub->offset() + addend;
3737 branch_offset = branch_target - address;
3738 gold_assert(!utils::has_overflow<26>(branch_offset));
3742 // At this point, if we still need to switch mode, the instruction
3743 // must either be a BLX or a BL that can be converted to a BLX.
3747 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3748 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3751 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
3752 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3753 return (utils::has_overflow<26>(branch_offset)
3754 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
3757 // Relocate THUMB long branches. This handles relocation types
3758 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3759 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3760 // undefined and we do not use PLT in this relocation. In such a case,
3761 // the branch is converted into an NOP.
3763 template<bool big_endian>
3764 typename Arm_relocate_functions<big_endian>::Status
3765 Arm_relocate_functions<big_endian>::thumb_branch_common(
3766 unsigned int r_type,
3767 const Relocate_info<32, big_endian>* relinfo,
3768 unsigned char *view,
3769 const Sized_symbol<32>* gsym,
3770 const Arm_relobj<big_endian>* object,
3772 const Symbol_value<32>* psymval,
3773 Arm_address address,
3774 Arm_address thumb_bit,
3775 bool is_weakly_undefined_without_plt)
3777 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3778 Valtype* wv = reinterpret_cast<Valtype*>(view);
3779 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3780 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3782 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3784 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
3785 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
3787 // Check that the instruction is valid.
3788 if (r_type == elfcpp::R_ARM_THM_CALL)
3790 if (!is_bl_insn && !is_blx_insn)
3791 return This::STATUS_BAD_RELOC;
3793 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
3795 // This cannot be a BLX.
3797 return This::STATUS_BAD_RELOC;
3799 else if (r_type == elfcpp::R_ARM_THM_XPC22)
3801 // Check for Thumb to Thumb call.
3803 return This::STATUS_BAD_RELOC;
3806 gold_warning(_("%s: Thumb BLX instruction targets "
3807 "thumb function '%s'."),
3808 object->name().c_str(),
3809 (gsym ? gsym->name() : "(local)"));
3810 // Convert BLX to BL.
3811 lower_insn |= 0x1000U;
3817 // A branch to an undefined weak symbol is turned into a jump to
3818 // the next instruction unless a PLT entry will be created.
3819 // The jump to the next instruction is optimized as a NOP.W for
3820 // Thumb-2 enabled architectures.
3821 const Target_arm<big_endian>* arm_target =
3822 Target_arm<big_endian>::default_target();
3823 if (is_weakly_undefined_without_plt)
3825 if (arm_target->may_use_thumb2_nop())
3827 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
3828 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
3832 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
3833 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
3835 return This::STATUS_OKAY;
3838 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
3839 Arm_address branch_target = psymval->value(object, addend);
3841 // For BLX, bit 1 of target address comes from bit 1 of base address.
3842 bool may_use_blx = arm_target->may_use_blx();
3843 if (thumb_bit == 0 && may_use_blx)
3844 branch_target = utils::bit_select(branch_target, address, 0x2);
3846 int32_t branch_offset = branch_target - address;
3848 // We need a stub if the branch offset is too large or if we need
3850 bool thumb2 = arm_target->using_thumb2();
3851 if ((!thumb2 && utils::has_overflow<23>(branch_offset))
3852 || (thumb2 && utils::has_overflow<25>(branch_offset))
3853 || ((thumb_bit == 0)
3854 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
3855 || r_type == elfcpp::R_ARM_THM_JUMP24)))
3857 Arm_address unadjusted_branch_target = psymval->value(object, 0);
3859 Stub_type stub_type =
3860 Reloc_stub::stub_type_for_reloc(r_type, address,
3861 unadjusted_branch_target,
3864 if (stub_type != arm_stub_none)
3866 Stub_table<big_endian>* stub_table =
3867 object->stub_table(relinfo->data_shndx);
3868 gold_assert(stub_table != NULL);
3870 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3871 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
3872 gold_assert(stub != NULL);
3873 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3874 branch_target = stub_table->address() + stub->offset() + addend;
3875 if (thumb_bit == 0 && may_use_blx)
3876 branch_target = utils::bit_select(branch_target, address, 0x2);
3877 branch_offset = branch_target - address;
3881 // At this point, if we still need to switch mode, the instruction
3882 // must either be a BLX or a BL that can be converted to a BLX.
3885 gold_assert(may_use_blx
3886 && (r_type == elfcpp::R_ARM_THM_CALL
3887 || r_type == elfcpp::R_ARM_THM_XPC22));
3888 // Make sure this is a BLX.
3889 lower_insn &= ~0x1000U;
3893 // Make sure this is a BL.
3894 lower_insn |= 0x1000U;
3897 // For a BLX instruction, make sure that the relocation is rounded up
3898 // to a word boundary. This follows the semantics of the instruction
3899 // which specifies that bit 1 of the target address will come from bit
3900 // 1 of the base address.
3901 if ((lower_insn & 0x5000U) == 0x4000U)
3902 gold_assert((branch_offset & 3) == 0);
3904 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
3905 // We use the Thumb-2 encoding, which is safe even if dealing with
3906 // a Thumb-1 instruction by virtue of our overflow check above. */
3907 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
3908 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
3910 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3911 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3913 gold_assert(!utils::has_overflow<25>(branch_offset));
3916 ? utils::has_overflow<25>(branch_offset)
3917 : utils::has_overflow<23>(branch_offset))
3918 ? This::STATUS_OVERFLOW
3919 : This::STATUS_OKAY);
3922 // Relocate THUMB-2 long conditional branches.
3923 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3924 // undefined and we do not use PLT in this relocation. In such a case,
3925 // the branch is converted into an NOP.
3927 template<bool big_endian>
3928 typename Arm_relocate_functions<big_endian>::Status
3929 Arm_relocate_functions<big_endian>::thm_jump19(
3930 unsigned char *view,
3931 const Arm_relobj<big_endian>* object,
3932 const Symbol_value<32>* psymval,
3933 Arm_address address,
3934 Arm_address thumb_bit)
3936 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3937 Valtype* wv = reinterpret_cast<Valtype*>(view);
3938 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3939 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3940 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
3942 Arm_address branch_target = psymval->value(object, addend);
3943 int32_t branch_offset = branch_target - address;
3945 // ??? Should handle interworking? GCC might someday try to
3946 // use this for tail calls.
3947 // FIXME: We do support thumb entry to PLT yet.
3950 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
3951 return This::STATUS_BAD_RELOC;
3954 // Put RELOCATION back into the insn.
3955 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
3956 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
3958 // Put the relocated value back in the object file:
3959 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3960 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3962 return (utils::has_overflow<21>(branch_offset)
3963 ? This::STATUS_OVERFLOW
3964 : This::STATUS_OKAY);
3967 // Get the GOT section, creating it if necessary.
3969 template<bool big_endian>
3970 Arm_output_data_got<big_endian>*
3971 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
3973 if (this->got_ == NULL)
3975 gold_assert(symtab != NULL && layout != NULL);
3977 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
3980 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3982 | elfcpp::SHF_WRITE),
3983 this->got_, false, false, false,
3985 // The old GNU linker creates a .got.plt section. We just
3986 // create another set of data in the .got section. Note that we
3987 // always create a PLT if we create a GOT, although the PLT
3989 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
3990 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3992 | elfcpp::SHF_WRITE),
3993 this->got_plt_, false, false,
3996 // The first three entries are reserved.
3997 this->got_plt_->set_current_data_size(3 * 4);
3999 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
4000 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
4001 Symbol_table::PREDEFINED,
4003 0, 0, elfcpp::STT_OBJECT,
4005 elfcpp::STV_HIDDEN, 0,
4011 // Get the dynamic reloc section, creating it if necessary.
4013 template<bool big_endian>
4014 typename Target_arm<big_endian>::Reloc_section*
4015 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
4017 if (this->rel_dyn_ == NULL)
4019 gold_assert(layout != NULL);
4020 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
4021 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
4022 elfcpp::SHF_ALLOC, this->rel_dyn_, true,
4023 false, false, false);
4025 return this->rel_dyn_;
4028 // Insn_template methods.
4030 // Return byte size of an instruction template.
4033 Insn_template::size() const
4035 switch (this->type())
4038 case THUMB16_SPECIAL_TYPE:
4049 // Return alignment of an instruction template.
4052 Insn_template::alignment() const
4054 switch (this->type())
4057 case THUMB16_SPECIAL_TYPE:
4068 // Stub_template methods.
4070 Stub_template::Stub_template(
4071 Stub_type type, const Insn_template* insns,
4073 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4074 entry_in_thumb_mode_(false), relocs_()
4078 // Compute byte size and alignment of stub template.
4079 for (size_t i = 0; i < insn_count; i++)
4081 unsigned insn_alignment = insns[i].alignment();
4082 size_t insn_size = insns[i].size();
4083 gold_assert((offset & (insn_alignment - 1)) == 0);
4084 this->alignment_ = std::max(this->alignment_, insn_alignment);
4085 switch (insns[i].type())
4087 case Insn_template::THUMB16_TYPE:
4088 case Insn_template::THUMB16_SPECIAL_TYPE:
4090 this->entry_in_thumb_mode_ = true;
4093 case Insn_template::THUMB32_TYPE:
4094 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4095 this->relocs_.push_back(Reloc(i, offset));
4097 this->entry_in_thumb_mode_ = true;
4100 case Insn_template::ARM_TYPE:
4101 // Handle cases where the target is encoded within the
4103 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4104 this->relocs_.push_back(Reloc(i, offset));
4107 case Insn_template::DATA_TYPE:
4108 // Entry point cannot be data.
4109 gold_assert(i != 0);
4110 this->relocs_.push_back(Reloc(i, offset));
4116 offset += insn_size;
4118 this->size_ = offset;
4123 // Template to implement do_write for a specific target endianity.
4125 template<bool big_endian>
4127 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4129 const Stub_template* stub_template = this->stub_template();
4130 const Insn_template* insns = stub_template->insns();
4132 // FIXME: We do not handle BE8 encoding yet.
4133 unsigned char* pov = view;
4134 for (size_t i = 0; i < stub_template->insn_count(); i++)
4136 switch (insns[i].type())
4138 case Insn_template::THUMB16_TYPE:
4139 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4141 case Insn_template::THUMB16_SPECIAL_TYPE:
4142 elfcpp::Swap<16, big_endian>::writeval(
4144 this->thumb16_special(i));
4146 case Insn_template::THUMB32_TYPE:
4148 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4149 uint32_t lo = insns[i].data() & 0xffff;
4150 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4151 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4154 case Insn_template::ARM_TYPE:
4155 case Insn_template::DATA_TYPE:
4156 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4161 pov += insns[i].size();
4163 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4166 // Reloc_stub::Key methods.
4168 // Dump a Key as a string for debugging.
4171 Reloc_stub::Key::name() const
4173 if (this->r_sym_ == invalid_index)
4175 // Global symbol key name
4176 // <stub-type>:<symbol name>:<addend>.
4177 const std::string sym_name = this->u_.symbol->name();
4178 // We need to print two hex number and two colons. So just add 100 bytes
4179 // to the symbol name size.
4180 size_t len = sym_name.size() + 100;
4181 char* buffer = new char[len];
4182 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4183 sym_name.c_str(), this->addend_);
4184 gold_assert(c > 0 && c < static_cast<int>(len));
4186 return std::string(buffer);
4190 // local symbol key name
4191 // <stub-type>:<object>:<r_sym>:<addend>.
4192 const size_t len = 200;
4194 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4195 this->u_.relobj, this->r_sym_, this->addend_);
4196 gold_assert(c > 0 && c < static_cast<int>(len));
4197 return std::string(buffer);
4201 // Reloc_stub methods.
4203 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4204 // LOCATION to DESTINATION.
4205 // This code is based on the arm_type_of_stub function in
4206 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
4210 Reloc_stub::stub_type_for_reloc(
4211 unsigned int r_type,
4212 Arm_address location,
4213 Arm_address destination,
4214 bool target_is_thumb)
4216 Stub_type stub_type = arm_stub_none;
4218 // This is a bit ugly but we want to avoid using a templated class for
4219 // big and little endianities.
4221 bool should_force_pic_veneer;
4224 if (parameters->target().is_big_endian())
4226 const Target_arm<true>* big_endian_target =
4227 Target_arm<true>::default_target();
4228 may_use_blx = big_endian_target->may_use_blx();
4229 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4230 thumb2 = big_endian_target->using_thumb2();
4231 thumb_only = big_endian_target->using_thumb_only();
4235 const Target_arm<false>* little_endian_target =
4236 Target_arm<false>::default_target();
4237 may_use_blx = little_endian_target->may_use_blx();
4238 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4239 thumb2 = little_endian_target->using_thumb2();
4240 thumb_only = little_endian_target->using_thumb_only();
4243 int64_t branch_offset;
4244 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4246 // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
4247 // base address (instruction address + 4).
4248 if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
4249 destination = utils::bit_select(destination, location, 0x2);
4250 branch_offset = static_cast<int64_t>(destination) - location;
4252 // Handle cases where:
4253 // - this call goes too far (different Thumb/Thumb2 max
4255 // - it's a Thumb->Arm call and blx is not available, or it's a
4256 // Thumb->Arm branch (not bl). A stub is needed in this case.
4258 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4259 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4261 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4262 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4263 || ((!target_is_thumb)
4264 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4265 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4267 if (target_is_thumb)
4272 stub_type = (parameters->options().shared()
4273 || should_force_pic_veneer)
4276 && (r_type == elfcpp::R_ARM_THM_CALL))
4277 // V5T and above. Stub starts with ARM code, so
4278 // we must be able to switch mode before
4279 // reaching it, which is only possible for 'bl'
4280 // (ie R_ARM_THM_CALL relocation).
4281 ? arm_stub_long_branch_any_thumb_pic
4282 // On V4T, use Thumb code only.
4283 : arm_stub_long_branch_v4t_thumb_thumb_pic)
4287 && (r_type == elfcpp::R_ARM_THM_CALL))
4288 ? arm_stub_long_branch_any_any // V5T and above.
4289 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
4293 stub_type = (parameters->options().shared()
4294 || should_force_pic_veneer)
4295 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4296 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4303 // FIXME: We should check that the input section is from an
4304 // object that has interwork enabled.
4306 stub_type = (parameters->options().shared()
4307 || should_force_pic_veneer)
4310 && (r_type == elfcpp::R_ARM_THM_CALL))
4311 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4312 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4316 && (r_type == elfcpp::R_ARM_THM_CALL))
4317 ? arm_stub_long_branch_any_any // V5T and above.
4318 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4320 // Handle v4t short branches.
4321 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4322 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4323 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4324 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4328 else if (r_type == elfcpp::R_ARM_CALL
4329 || r_type == elfcpp::R_ARM_JUMP24
4330 || r_type == elfcpp::R_ARM_PLT32)
4332 branch_offset = static_cast<int64_t>(destination) - location;
4333 if (target_is_thumb)
4337 // FIXME: We should check that the input section is from an
4338 // object that has interwork enabled.
4340 // We have an extra 2-bytes reach because of
4341 // the mode change (bit 24 (H) of BLX encoding).
4342 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4343 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4344 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4345 || (r_type == elfcpp::R_ARM_JUMP24)
4346 || (r_type == elfcpp::R_ARM_PLT32))
4348 stub_type = (parameters->options().shared()
4349 || should_force_pic_veneer)
4352 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4353 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4357 ? arm_stub_long_branch_any_any // V5T and above.
4358 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4364 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4365 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4367 stub_type = (parameters->options().shared()
4368 || should_force_pic_veneer)
4369 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4370 : arm_stub_long_branch_any_any; /// non-PIC.
4378 // Cortex_a8_stub methods.
4380 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4381 // I is the position of the instruction template in the stub template.
4384 Cortex_a8_stub::do_thumb16_special(size_t i)
4386 // The only use of this is to copy condition code from a conditional
4387 // branch being worked around to the corresponding conditional branch in
4389 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4391 uint16_t data = this->stub_template()->insns()[i].data();
4392 gold_assert((data & 0xff00U) == 0xd000U);
4393 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4397 // Stub_factory methods.
4399 Stub_factory::Stub_factory()
4401 // The instruction template sequences are declared as static
4402 // objects and initialized first time the constructor runs.
4404 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4405 // to reach the stub if necessary.
4406 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4408 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4409 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4410 // dcd R_ARM_ABS32(X)
4413 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4415 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4417 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4418 Insn_template::arm_insn(0xe12fff1c), // bx ip
4419 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4420 // dcd R_ARM_ABS32(X)
4423 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4424 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4426 Insn_template::thumb16_insn(0xb401), // push {r0}
4427 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4428 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4429 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4430 Insn_template::thumb16_insn(0x4760), // bx ip
4431 Insn_template::thumb16_insn(0xbf00), // nop
4432 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4433 // dcd R_ARM_ABS32(X)
4436 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4438 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4440 Insn_template::thumb16_insn(0x4778), // bx pc
4441 Insn_template::thumb16_insn(0x46c0), // nop
4442 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4443 Insn_template::arm_insn(0xe12fff1c), // bx ip
4444 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4445 // dcd R_ARM_ABS32(X)
4448 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4450 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4452 Insn_template::thumb16_insn(0x4778), // bx pc
4453 Insn_template::thumb16_insn(0x46c0), // nop
4454 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4455 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4456 // dcd R_ARM_ABS32(X)
4459 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4460 // one, when the destination is close enough.
4461 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4463 Insn_template::thumb16_insn(0x4778), // bx pc
4464 Insn_template::thumb16_insn(0x46c0), // nop
4465 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4468 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4469 // blx to reach the stub if necessary.
4470 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4472 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4473 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4474 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4475 // dcd R_ARM_REL32(X-4)
4478 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4479 // blx to reach the stub if necessary. We can not add into pc;
4480 // it is not guaranteed to mode switch (different in ARMv6 and
4482 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4484 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4485 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4486 Insn_template::arm_insn(0xe12fff1c), // bx ip
4487 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4488 // dcd R_ARM_REL32(X)
4491 // V4T ARM -> ARM long branch stub, PIC.
4492 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4494 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4495 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4496 Insn_template::arm_insn(0xe12fff1c), // bx ip
4497 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4498 // dcd R_ARM_REL32(X)
4501 // V4T Thumb -> ARM long branch stub, PIC.
4502 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4504 Insn_template::thumb16_insn(0x4778), // bx pc
4505 Insn_template::thumb16_insn(0x46c0), // nop
4506 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4507 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4508 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4509 // dcd R_ARM_REL32(X)
4512 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4514 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4516 Insn_template::thumb16_insn(0xb401), // push {r0}
4517 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4518 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4519 Insn_template::thumb16_insn(0x4484), // add ip, r0
4520 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4521 Insn_template::thumb16_insn(0x4760), // bx ip
4522 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4523 // dcd R_ARM_REL32(X)
4526 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4528 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4530 Insn_template::thumb16_insn(0x4778), // bx pc
4531 Insn_template::thumb16_insn(0x46c0), // nop
4532 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4533 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4534 Insn_template::arm_insn(0xe12fff1c), // bx ip
4535 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4536 // dcd R_ARM_REL32(X)
4539 // Cortex-A8 erratum-workaround stubs.
4541 // Stub used for conditional branches (which may be beyond +/-1MB away,
4542 // so we can't use a conditional branch to reach this stub).
4549 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4551 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4552 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4553 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4557 // Stub used for b.w and bl.w instructions.
4559 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4561 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4564 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4566 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4569 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4570 // instruction (which switches to ARM mode) to point to this stub. Jump to
4571 // the real destination using an ARM-mode branch.
4572 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4574 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4577 // Stub used to provide an interworking for R_ARM_V4BX relocation
4578 // (bx r[n] instruction).
4579 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4581 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4582 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4583 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4586 // Fill in the stub template look-up table. Stub templates are constructed
4587 // per instance of Stub_factory for fast look-up without locking
4588 // in a thread-enabled environment.
4590 this->stub_templates_[arm_stub_none] =
4591 new Stub_template(arm_stub_none, NULL, 0);
4593 #define DEF_STUB(x) \
4597 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4598 Stub_type type = arm_stub_##x; \
4599 this->stub_templates_[type] = \
4600 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4608 // Stub_table methods.
4610 // Removel all Cortex-A8 stub.
4612 template<bool big_endian>
4614 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4616 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4617 p != this->cortex_a8_stubs_.end();
4620 this->cortex_a8_stubs_.clear();
4623 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4625 template<bool big_endian>
4627 Stub_table<big_endian>::relocate_stub(
4629 const Relocate_info<32, big_endian>* relinfo,
4630 Target_arm<big_endian>* arm_target,
4631 Output_section* output_section,
4632 unsigned char* view,
4633 Arm_address address,
4634 section_size_type view_size)
4636 const Stub_template* stub_template = stub->stub_template();
4637 if (stub_template->reloc_count() != 0)
4639 // Adjust view to cover the stub only.
4640 section_size_type offset = stub->offset();
4641 section_size_type stub_size = stub_template->size();
4642 gold_assert(offset + stub_size <= view_size);
4644 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4645 address + offset, stub_size);
4649 // Relocate all stubs in this stub table.
4651 template<bool big_endian>
4653 Stub_table<big_endian>::relocate_stubs(
4654 const Relocate_info<32, big_endian>* relinfo,
4655 Target_arm<big_endian>* arm_target,
4656 Output_section* output_section,
4657 unsigned char* view,
4658 Arm_address address,
4659 section_size_type view_size)
4661 // If we are passed a view bigger than the stub table's. we need to
4663 gold_assert(address == this->address()
4665 == static_cast<section_size_type>(this->data_size())));
4667 // Relocate all relocation stubs.
4668 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4669 p != this->reloc_stubs_.end();
4671 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4672 address, view_size);
4674 // Relocate all Cortex-A8 stubs.
4675 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4676 p != this->cortex_a8_stubs_.end();
4678 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4679 address, view_size);
4681 // Relocate all ARM V4BX stubs.
4682 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4683 p != this->arm_v4bx_stubs_.end();
4687 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4688 address, view_size);
4692 // Write out the stubs to file.
4694 template<bool big_endian>
4696 Stub_table<big_endian>::do_write(Output_file* of)
4698 off_t offset = this->offset();
4699 const section_size_type oview_size =
4700 convert_to_section_size_type(this->data_size());
4701 unsigned char* const oview = of->get_output_view(offset, oview_size);
4703 // Write relocation stubs.
4704 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4705 p != this->reloc_stubs_.end();
4708 Reloc_stub* stub = p->second;
4709 Arm_address address = this->address() + stub->offset();
4711 == align_address(address,
4712 stub->stub_template()->alignment()));
4713 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4717 // Write Cortex-A8 stubs.
4718 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4719 p != this->cortex_a8_stubs_.end();
4722 Cortex_a8_stub* stub = p->second;
4723 Arm_address address = this->address() + stub->offset();
4725 == align_address(address,
4726 stub->stub_template()->alignment()));
4727 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4731 // Write ARM V4BX relocation stubs.
4732 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4733 p != this->arm_v4bx_stubs_.end();
4739 Arm_address address = this->address() + (*p)->offset();
4741 == align_address(address,
4742 (*p)->stub_template()->alignment()));
4743 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4747 of->write_output_view(this->offset(), oview_size, oview);
4750 // Update the data size and address alignment of the stub table at the end
4751 // of a relaxation pass. Return true if either the data size or the
4752 // alignment changed in this relaxation pass.
4754 template<bool big_endian>
4756 Stub_table<big_endian>::update_data_size_and_addralign()
4758 // Go over all stubs in table to compute data size and address alignment.
4759 off_t size = this->reloc_stubs_size_;
4760 unsigned addralign = this->reloc_stubs_addralign_;
4762 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4763 p != this->cortex_a8_stubs_.end();
4766 const Stub_template* stub_template = p->second->stub_template();
4767 addralign = std::max(addralign, stub_template->alignment());
4768 size = (align_address(size, stub_template->alignment())
4769 + stub_template->size());
4772 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4773 p != this->arm_v4bx_stubs_.end();
4779 const Stub_template* stub_template = (*p)->stub_template();
4780 addralign = std::max(addralign, stub_template->alignment());
4781 size = (align_address(size, stub_template->alignment())
4782 + stub_template->size());
4785 // Check if either data size or alignment changed in this pass.
4786 // Update prev_data_size_ and prev_addralign_. These will be used
4787 // as the current data size and address alignment for the next pass.
4788 bool changed = size != this->prev_data_size_;
4789 this->prev_data_size_ = size;
4791 if (addralign != this->prev_addralign_)
4793 this->prev_addralign_ = addralign;
4798 // Finalize the stubs. This sets the offsets of the stubs within the stub
4799 // table. It also marks all input sections needing Cortex-A8 workaround.
4801 template<bool big_endian>
4803 Stub_table<big_endian>::finalize_stubs()
4805 off_t off = this->reloc_stubs_size_;
4806 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4807 p != this->cortex_a8_stubs_.end();
4810 Cortex_a8_stub* stub = p->second;
4811 const Stub_template* stub_template = stub->stub_template();
4812 uint64_t stub_addralign = stub_template->alignment();
4813 off = align_address(off, stub_addralign);
4814 stub->set_offset(off);
4815 off += stub_template->size();
4817 // Mark input section so that we can determine later if a code section
4818 // needs the Cortex-A8 workaround quickly.
4819 Arm_relobj<big_endian>* arm_relobj =
4820 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
4821 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
4824 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4825 p != this->arm_v4bx_stubs_.end();
4831 const Stub_template* stub_template = (*p)->stub_template();
4832 uint64_t stub_addralign = stub_template->alignment();
4833 off = align_address(off, stub_addralign);
4834 (*p)->set_offset(off);
4835 off += stub_template->size();
4838 gold_assert(off <= this->prev_data_size_);
4841 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
4842 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
4843 // of the address range seen by the linker.
4845 template<bool big_endian>
4847 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
4848 Target_arm<big_endian>* arm_target,
4849 unsigned char* view,
4850 Arm_address view_address,
4851 section_size_type view_size)
4853 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
4854 for (Cortex_a8_stub_list::const_iterator p =
4855 this->cortex_a8_stubs_.lower_bound(view_address);
4856 ((p != this->cortex_a8_stubs_.end())
4857 && (p->first < (view_address + view_size)));
4860 // We do not store the THUMB bit in the LSB of either the branch address
4861 // or the stub offset. There is no need to strip the LSB.
4862 Arm_address branch_address = p->first;
4863 const Cortex_a8_stub* stub = p->second;
4864 Arm_address stub_address = this->address() + stub->offset();
4866 // Offset of the branch instruction relative to this view.
4867 section_size_type offset =
4868 convert_to_section_size_type(branch_address - view_address);
4869 gold_assert((offset + 4) <= view_size);
4871 arm_target->apply_cortex_a8_workaround(stub, stub_address,
4872 view + offset, branch_address);
4876 // Arm_input_section methods.
4878 // Initialize an Arm_input_section.
4880 template<bool big_endian>
4882 Arm_input_section<big_endian>::init()
4884 Relobj* relobj = this->relobj();
4885 unsigned int shndx = this->shndx();
4887 // Cache these to speed up size and alignment queries. It is too slow
4888 // to call section_addraglin and section_size every time.
4889 this->original_addralign_ = relobj->section_addralign(shndx);
4890 this->original_size_ = relobj->section_size(shndx);
4892 // We want to make this look like the original input section after
4893 // output sections are finalized.
4894 Output_section* os = relobj->output_section(shndx);
4895 off_t offset = relobj->output_section_offset(shndx);
4896 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
4897 this->set_address(os->address() + offset);
4898 this->set_file_offset(os->offset() + offset);
4900 this->set_current_data_size(this->original_size_);
4901 this->finalize_data_size();
4904 template<bool big_endian>
4906 Arm_input_section<big_endian>::do_write(Output_file* of)
4908 // We have to write out the original section content.
4909 section_size_type section_size;
4910 const unsigned char* section_contents =
4911 this->relobj()->section_contents(this->shndx(), §ion_size, false);
4912 of->write(this->offset(), section_contents, section_size);
4914 // If this owns a stub table and it is not empty, write it.
4915 if (this->is_stub_table_owner() && !this->stub_table_->empty())
4916 this->stub_table_->write(of);
4919 // Finalize data size.
4921 template<bool big_endian>
4923 Arm_input_section<big_endian>::set_final_data_size()
4925 // If this owns a stub table, finalize its data size as well.
4926 if (this->is_stub_table_owner())
4928 uint64_t address = this->address();
4930 // The stub table comes after the original section contents.
4931 address += this->original_size_;
4932 address = align_address(address, this->stub_table_->addralign());
4933 off_t offset = this->offset() + (address - this->address());
4934 this->stub_table_->set_address_and_file_offset(address, offset);
4935 address += this->stub_table_->data_size();
4936 gold_assert(address == this->address() + this->current_data_size());
4939 this->set_data_size(this->current_data_size());
4942 // Reset address and file offset.
4944 template<bool big_endian>
4946 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
4948 // Size of the original input section contents.
4949 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
4951 // If this is a stub table owner, account for the stub table size.
4952 if (this->is_stub_table_owner())
4954 Stub_table<big_endian>* stub_table = this->stub_table_;
4956 // Reset the stub table's address and file offset. The
4957 // current data size for child will be updated after that.
4958 stub_table_->reset_address_and_file_offset();
4959 off = align_address(off, stub_table_->addralign());
4960 off += stub_table->current_data_size();
4963 this->set_current_data_size(off);
4966 // Arm_exidx_cantunwind methods.
4968 // Write this to Output file OF for a fixed endianity.
4970 template<bool big_endian>
4972 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
4974 off_t offset = this->offset();
4975 const section_size_type oview_size = 8;
4976 unsigned char* const oview = of->get_output_view(offset, oview_size);
4978 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
4979 Valtype* wv = reinterpret_cast<Valtype*>(oview);
4981 Output_section* os = this->relobj_->output_section(this->shndx_);
4982 gold_assert(os != NULL);
4984 Arm_relobj<big_endian>* arm_relobj =
4985 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
4986 Arm_address output_offset =
4987 arm_relobj->get_output_section_offset(this->shndx_);
4988 Arm_address section_start;
4989 if(output_offset != Arm_relobj<big_endian>::invalid_address)
4990 section_start = os->address() + output_offset;
4993 // Currently this only happens for a relaxed section.
4994 const Output_relaxed_input_section* poris =
4995 os->find_relaxed_input_section(this->relobj_, this->shndx_);
4996 gold_assert(poris != NULL);
4997 section_start = poris->address();
5000 // We always append this to the end of an EXIDX section.
5001 Arm_address output_address =
5002 section_start + this->relobj_->section_size(this->shndx_);
5004 // Write out the entry. The first word either points to the beginning
5005 // or after the end of a text section. The second word is the special
5006 // EXIDX_CANTUNWIND value.
5007 uint32_t prel31_offset = output_address - this->address();
5008 if (utils::has_overflow<31>(offset))
5009 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
5010 elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
5011 elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
5013 of->write_output_view(this->offset(), oview_size, oview);
5016 // Arm_exidx_merged_section methods.
5018 // Constructor for Arm_exidx_merged_section.
5019 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5020 // SECTION_OFFSET_MAP points to a section offset map describing how
5021 // parts of the input section are mapped to output. DELETED_BYTES is
5022 // the number of bytes deleted from the EXIDX input section.
5024 Arm_exidx_merged_section::Arm_exidx_merged_section(
5025 const Arm_exidx_input_section& exidx_input_section,
5026 const Arm_exidx_section_offset_map& section_offset_map,
5027 uint32_t deleted_bytes)
5028 : Output_relaxed_input_section(exidx_input_section.relobj(),
5029 exidx_input_section.shndx(),
5030 exidx_input_section.addralign()),
5031 exidx_input_section_(exidx_input_section),
5032 section_offset_map_(section_offset_map)
5034 // Fix size here so that we do not need to implement set_final_data_size.
5035 this->set_data_size(exidx_input_section.size() - deleted_bytes);
5036 this->fix_data_size();
5039 // Given an input OBJECT, an input section index SHNDX within that
5040 // object, and an OFFSET relative to the start of that input
5041 // section, return whether or not the corresponding offset within
5042 // the output section is known. If this function returns true, it
5043 // sets *POUTPUT to the output offset. The value -1 indicates that
5044 // this input offset is being discarded.
5047 Arm_exidx_merged_section::do_output_offset(
5048 const Relobj* relobj,
5050 section_offset_type offset,
5051 section_offset_type* poutput) const
5053 // We only handle offsets for the original EXIDX input section.
5054 if (relobj != this->exidx_input_section_.relobj()
5055 || shndx != this->exidx_input_section_.shndx())
5058 section_offset_type section_size =
5059 convert_types<section_offset_type>(this->exidx_input_section_.size());
5060 if (offset < 0 || offset >= section_size)
5061 // Input offset is out of valid range.
5065 // We need to look up the section offset map to determine the output
5066 // offset. Find the reference point in map that is first offset
5067 // bigger than or equal to this offset.
5068 Arm_exidx_section_offset_map::const_iterator p =
5069 this->section_offset_map_.lower_bound(offset);
5071 // The section offset maps are build such that this should not happen if
5072 // input offset is in the valid range.
5073 gold_assert(p != this->section_offset_map_.end());
5075 // We need to check if this is dropped.
5076 section_offset_type ref = p->first;
5077 section_offset_type mapped_ref = p->second;
5079 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5080 // Offset is present in output.
5081 *poutput = mapped_ref + (offset - ref);
5083 // Offset is discarded owing to EXIDX entry merging.
5090 // Write this to output file OF.
5093 Arm_exidx_merged_section::do_write(Output_file* of)
5095 // If we retain or discard the whole EXIDX input section, we would
5097 gold_assert(this->data_size() != this->exidx_input_section_.size()
5098 && this->data_size() != 0);
5100 off_t offset = this->offset();
5101 const section_size_type oview_size = this->data_size();
5102 unsigned char* const oview = of->get_output_view(offset, oview_size);
5104 Output_section* os = this->relobj()->output_section(this->shndx());
5105 gold_assert(os != NULL);
5107 // Get contents of EXIDX input section.
5108 section_size_type section_size;
5109 const unsigned char* section_contents =
5110 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5111 gold_assert(section_size == this->exidx_input_section_.size());
5113 // Go over spans of input offsets and write only those that are not
5115 section_offset_type in_start = 0;
5116 section_offset_type out_start = 0;
5117 for(Arm_exidx_section_offset_map::const_iterator p =
5118 this->section_offset_map_.begin();
5119 p != this->section_offset_map_.end();
5122 section_offset_type in_end = p->first;
5123 gold_assert(in_end >= in_start);
5124 section_offset_type out_end = p->second;
5125 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5128 size_t out_chunk_size =
5129 convert_types<size_t>(out_end - out_start + 1);
5130 gold_assert(out_chunk_size == in_chunk_size);
5131 memcpy(oview + out_start, section_contents + in_start,
5133 out_start += out_chunk_size;
5135 in_start += in_chunk_size;
5138 gold_assert(convert_to_section_size_type(out_start) == oview_size);
5139 of->write_output_view(this->offset(), oview_size, oview);
5142 // Arm_exidx_fixup methods.
5144 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5145 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5146 // points to the end of the last seen EXIDX section.
5149 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5151 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5152 && this->last_input_section_ != NULL)
5154 Relobj* relobj = this->last_input_section_->relobj();
5155 unsigned int text_shndx = this->last_input_section_->link();
5156 Arm_exidx_cantunwind* cantunwind =
5157 new Arm_exidx_cantunwind(relobj, text_shndx);
5158 this->exidx_output_section_->add_output_section_data(cantunwind);
5159 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5163 // Process an EXIDX section entry in input. Return whether this entry
5164 // can be deleted in the output. SECOND_WORD in the second word of the
5168 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5171 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5173 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5174 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5175 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5177 else if ((second_word & 0x80000000) != 0)
5179 // Inlined unwinding data. Merge if equal to previous.
5180 delete_entry = (this->last_unwind_type_ == UT_INLINED_ENTRY
5181 && this->last_inlined_entry_ == second_word);
5182 this->last_unwind_type_ = UT_INLINED_ENTRY;
5183 this->last_inlined_entry_ = second_word;
5187 // Normal table entry. In theory we could merge these too,
5188 // but duplicate entries are likely to be much less common.
5189 delete_entry = false;
5190 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5192 return delete_entry;
5195 // Update the current section offset map during EXIDX section fix-up.
5196 // If there is no map, create one. INPUT_OFFSET is the offset of a
5197 // reference point, DELETED_BYTES is the number of deleted by in the
5198 // section so far. If DELETE_ENTRY is true, the reference point and
5199 // all offsets after the previous reference point are discarded.
5202 Arm_exidx_fixup::update_offset_map(
5203 section_offset_type input_offset,
5204 section_size_type deleted_bytes,
5207 if (this->section_offset_map_ == NULL)
5208 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5209 section_offset_type output_offset =
5211 ? Arm_exidx_input_section::invalid_offset
5212 : input_offset - deleted_bytes);
5213 (*this->section_offset_map_)[input_offset] = output_offset;
5216 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5217 // bytes deleted. If some entries are merged, also store a pointer to a newly
5218 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5219 // caller owns the map and is responsible for releasing it after use.
5221 template<bool big_endian>
5223 Arm_exidx_fixup::process_exidx_section(
5224 const Arm_exidx_input_section* exidx_input_section,
5225 Arm_exidx_section_offset_map** psection_offset_map)
5227 Relobj* relobj = exidx_input_section->relobj();
5228 unsigned shndx = exidx_input_section->shndx();
5229 section_size_type section_size;
5230 const unsigned char* section_contents =
5231 relobj->section_contents(shndx, §ion_size, false);
5233 if ((section_size % 8) != 0)
5235 // Something is wrong with this section. Better not touch it.
5236 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5237 relobj->name().c_str(), shndx);
5238 this->last_input_section_ = exidx_input_section;
5239 this->last_unwind_type_ = UT_NONE;
5243 uint32_t deleted_bytes = 0;
5244 bool prev_delete_entry = false;
5245 gold_assert(this->section_offset_map_ == NULL);
5247 for (section_size_type i = 0; i < section_size; i += 8)
5249 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5251 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5252 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5254 bool delete_entry = this->process_exidx_entry(second_word);
5256 // Entry deletion causes changes in output offsets. We use a std::map
5257 // to record these. And entry (x, y) means input offset x
5258 // is mapped to output offset y. If y is invalid_offset, then x is
5259 // dropped in the output. Because of the way std::map::lower_bound
5260 // works, we record the last offset in a region w.r.t to keeping or
5261 // dropping. If there is no entry (x0, y0) for an input offset x0,
5262 // the output offset y0 of it is determined by the output offset y1 of
5263 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5264 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5266 if (delete_entry != prev_delete_entry && i != 0)
5267 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5269 // Update total deleted bytes for this entry.
5273 prev_delete_entry = delete_entry;
5276 // If section offset map is not NULL, make an entry for the end of
5278 if (this->section_offset_map_ != NULL)
5279 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5281 *psection_offset_map = this->section_offset_map_;
5282 this->section_offset_map_ = NULL;
5283 this->last_input_section_ = exidx_input_section;
5285 // Set the first output text section so that we can link the EXIDX output
5286 // section to it. Ignore any EXIDX input section that is completely merged.
5287 if (this->first_output_text_section_ == NULL
5288 && deleted_bytes != section_size)
5290 unsigned int link = exidx_input_section->link();
5291 Output_section* os = relobj->output_section(link);
5292 gold_assert(os != NULL);
5293 this->first_output_text_section_ = os;
5296 return deleted_bytes;
5299 // Arm_output_section methods.
5301 // Create a stub group for input sections from BEGIN to END. OWNER
5302 // points to the input section to be the owner a new stub table.
5304 template<bool big_endian>
5306 Arm_output_section<big_endian>::create_stub_group(
5307 Input_section_list::const_iterator begin,
5308 Input_section_list::const_iterator end,
5309 Input_section_list::const_iterator owner,
5310 Target_arm<big_endian>* target,
5311 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
5313 // We use a different kind of relaxed section in an EXIDX section.
5314 // The static casting from Output_relaxed_input_section to
5315 // Arm_input_section is invalid in an EXIDX section. We are okay
5316 // because we should not be calling this for an EXIDX section.
5317 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5319 // Currently we convert ordinary input sections into relaxed sections only
5320 // at this point but we may want to support creating relaxed input section
5321 // very early. So we check here to see if owner is already a relaxed
5324 Arm_input_section<big_endian>* arm_input_section;
5325 if (owner->is_relaxed_input_section())
5328 Arm_input_section<big_endian>::as_arm_input_section(
5329 owner->relaxed_input_section());
5333 gold_assert(owner->is_input_section());
5334 // Create a new relaxed input section.
5336 target->new_arm_input_section(owner->relobj(), owner->shndx());
5337 new_relaxed_sections->push_back(arm_input_section);
5340 // Create a stub table.
5341 Stub_table<big_endian>* stub_table =
5342 target->new_stub_table(arm_input_section);
5344 arm_input_section->set_stub_table(stub_table);
5346 Input_section_list::const_iterator p = begin;
5347 Input_section_list::const_iterator prev_p;
5349 // Look for input sections or relaxed input sections in [begin ... end].
5352 if (p->is_input_section() || p->is_relaxed_input_section())
5354 // The stub table information for input sections live
5355 // in their objects.
5356 Arm_relobj<big_endian>* arm_relobj =
5357 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5358 arm_relobj->set_stub_table(p->shndx(), stub_table);
5362 while (prev_p != end);
5365 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5366 // of stub groups. We grow a stub group by adding input section until the
5367 // size is just below GROUP_SIZE. The last input section will be converted
5368 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5369 // input section after the stub table, effectively double the group size.
5371 // This is similar to the group_sections() function in elf32-arm.c but is
5372 // implemented differently.
5374 template<bool big_endian>
5376 Arm_output_section<big_endian>::group_sections(
5377 section_size_type group_size,
5378 bool stubs_always_after_branch,
5379 Target_arm<big_endian>* target)
5381 // We only care about sections containing code.
5382 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5385 // States for grouping.
5388 // No group is being built.
5390 // A group is being built but the stub table is not found yet.
5391 // We keep group a stub group until the size is just under GROUP_SIZE.
5392 // The last input section in the group will be used as the stub table.
5393 FINDING_STUB_SECTION,
5394 // A group is being built and we have already found a stub table.
5395 // We enter this state to grow a stub group by adding input section
5396 // after the stub table. This effectively doubles the group size.
5400 // Any newly created relaxed sections are stored here.
5401 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5403 State state = NO_GROUP;
5404 section_size_type off = 0;
5405 section_size_type group_begin_offset = 0;
5406 section_size_type group_end_offset = 0;
5407 section_size_type stub_table_end_offset = 0;
5408 Input_section_list::const_iterator group_begin =
5409 this->input_sections().end();
5410 Input_section_list::const_iterator stub_table =
5411 this->input_sections().end();
5412 Input_section_list::const_iterator group_end = this->input_sections().end();
5413 for (Input_section_list::const_iterator p = this->input_sections().begin();
5414 p != this->input_sections().end();
5417 section_size_type section_begin_offset =
5418 align_address(off, p->addralign());
5419 section_size_type section_end_offset =
5420 section_begin_offset + p->data_size();
5422 // Check to see if we should group the previously seens sections.
5428 case FINDING_STUB_SECTION:
5429 // Adding this section makes the group larger than GROUP_SIZE.
5430 if (section_end_offset - group_begin_offset >= group_size)
5432 if (stubs_always_after_branch)
5434 gold_assert(group_end != this->input_sections().end());
5435 this->create_stub_group(group_begin, group_end, group_end,
5436 target, &new_relaxed_sections);
5441 // But wait, there's more! Input sections up to
5442 // stub_group_size bytes after the stub table can be
5443 // handled by it too.
5444 state = HAS_STUB_SECTION;
5445 stub_table = group_end;
5446 stub_table_end_offset = group_end_offset;
5451 case HAS_STUB_SECTION:
5452 // Adding this section makes the post stub-section group larger
5454 if (section_end_offset - stub_table_end_offset >= group_size)
5456 gold_assert(group_end != this->input_sections().end());
5457 this->create_stub_group(group_begin, group_end, stub_table,
5458 target, &new_relaxed_sections);
5467 // If we see an input section and currently there is no group, start
5468 // a new one. Skip any empty sections.
5469 if ((p->is_input_section() || p->is_relaxed_input_section())
5470 && (p->relobj()->section_size(p->shndx()) != 0))
5472 if (state == NO_GROUP)
5474 state = FINDING_STUB_SECTION;
5476 group_begin_offset = section_begin_offset;
5479 // Keep track of the last input section seen.
5481 group_end_offset = section_end_offset;
5484 off = section_end_offset;
5487 // Create a stub group for any ungrouped sections.
5488 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5490 gold_assert(group_end != this->input_sections().end());
5491 this->create_stub_group(group_begin, group_end,
5492 (state == FINDING_STUB_SECTION
5495 target, &new_relaxed_sections);
5498 // Convert input section into relaxed input section in a batch.
5499 if (!new_relaxed_sections.empty())
5500 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5502 // Update the section offsets
5503 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5505 Arm_relobj<big_endian>* arm_relobj =
5506 Arm_relobj<big_endian>::as_arm_relobj(
5507 new_relaxed_sections[i]->relobj());
5508 unsigned int shndx = new_relaxed_sections[i]->shndx();
5509 // Tell Arm_relobj that this input section is converted.
5510 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5514 // Append non empty text sections in this to LIST in ascending
5515 // order of their position in this.
5517 template<bool big_endian>
5519 Arm_output_section<big_endian>::append_text_sections_to_list(
5520 Text_section_list* list)
5522 // We only care about text sections.
5523 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5526 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5528 for (Input_section_list::const_iterator p = this->input_sections().begin();
5529 p != this->input_sections().end();
5532 // We only care about plain or relaxed input sections. We also
5533 // ignore any merged sections.
5534 if ((p->is_input_section() || p->is_relaxed_input_section())
5535 && p->data_size() != 0)
5536 list->push_back(Text_section_list::value_type(p->relobj(),
5541 template<bool big_endian>
5543 Arm_output_section<big_endian>::fix_exidx_coverage(
5545 const Text_section_list& sorted_text_sections,
5546 Symbol_table* symtab)
5548 // We should only do this for the EXIDX output section.
5549 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5551 // We don't want the relaxation loop to undo these changes, so we discard
5552 // the current saved states and take another one after the fix-up.
5553 this->discard_states();
5555 // Remove all input sections.
5556 uint64_t address = this->address();
5557 typedef std::list<Simple_input_section> Simple_input_section_list;
5558 Simple_input_section_list input_sections;
5559 this->reset_address_and_file_offset();
5560 this->get_input_sections(address, std::string(""), &input_sections);
5562 if (!this->input_sections().empty())
5563 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5565 // Go through all the known input sections and record them.
5566 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5567 Section_id_set known_input_sections;
5568 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5569 p != input_sections.end();
5572 // This should never happen. At this point, we should only see
5573 // plain EXIDX input sections.
5574 gold_assert(!p->is_relaxed_input_section());
5575 known_input_sections.insert(Section_id(p->relobj(), p->shndx()));
5578 Arm_exidx_fixup exidx_fixup(this);
5580 // Go over the sorted text sections.
5581 Section_id_set processed_input_sections;
5582 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5583 p != sorted_text_sections.end();
5586 Relobj* relobj = p->first;
5587 unsigned int shndx = p->second;
5589 Arm_relobj<big_endian>* arm_relobj =
5590 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5591 const Arm_exidx_input_section* exidx_input_section =
5592 arm_relobj->exidx_input_section_by_link(shndx);
5594 // If this text section has no EXIDX section, force an EXIDX_CANTUNWIND
5595 // entry pointing to the end of the last seen EXIDX section.
5596 if (exidx_input_section == NULL)
5598 exidx_fixup.add_exidx_cantunwind_as_needed();
5602 Relobj* exidx_relobj = exidx_input_section->relobj();
5603 unsigned int exidx_shndx = exidx_input_section->shndx();
5604 Section_id sid(exidx_relobj, exidx_shndx);
5605 if (known_input_sections.find(sid) == known_input_sections.end())
5607 // This is odd. We have not seen this EXIDX input section before.
5608 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5609 // issue a warning instead. We assume the user knows what he
5610 // or she is doing. Otherwise, this is an error.
5611 if (layout->script_options()->saw_sections_clause())
5612 gold_warning(_("unwinding may not work because EXIDX input section"
5613 " %u of %s is not in EXIDX output section"),
5614 exidx_shndx, exidx_relobj->name().c_str());
5616 gold_error(_("unwinding may not work because EXIDX input section"
5617 " %u of %s is not in EXIDX output section"),
5618 exidx_shndx, exidx_relobj->name().c_str());
5620 exidx_fixup.add_exidx_cantunwind_as_needed();
5624 // Fix up coverage and append input section to output data list.
5625 Arm_exidx_section_offset_map* section_offset_map = NULL;
5626 uint32_t deleted_bytes =
5627 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5628 §ion_offset_map);
5630 if (deleted_bytes == exidx_input_section->size())
5632 // The whole EXIDX section got merged. Remove it from output.
5633 gold_assert(section_offset_map == NULL);
5634 exidx_relobj->set_output_section(exidx_shndx, NULL);
5636 // All local symbols defined in this input section will be dropped.
5637 // We need to adjust output local symbol count.
5638 arm_relobj->set_output_local_symbol_count_needs_update();
5640 else if (deleted_bytes > 0)
5642 // Some entries are merged. We need to convert this EXIDX input
5643 // section into a relaxed section.
5644 gold_assert(section_offset_map != NULL);
5645 Arm_exidx_merged_section* merged_section =
5646 new Arm_exidx_merged_section(*exidx_input_section,
5647 *section_offset_map, deleted_bytes);
5648 this->add_relaxed_input_section(merged_section);
5649 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5651 // All local symbols defined in discarded portions of this input
5652 // section will be dropped. We need to adjust output local symbol
5654 arm_relobj->set_output_local_symbol_count_needs_update();
5658 // Just add back the EXIDX input section.
5659 gold_assert(section_offset_map == NULL);
5660 Output_section::Simple_input_section sis(exidx_relobj, exidx_shndx);
5661 this->add_simple_input_section(sis, exidx_input_section->size(),
5662 exidx_input_section->addralign());
5665 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5668 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5669 exidx_fixup.add_exidx_cantunwind_as_needed();
5671 // Remove any known EXIDX input sections that are not processed.
5672 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5673 p != input_sections.end();
5676 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5677 == processed_input_sections.end())
5679 // We only discard a known EXIDX section because its linked
5680 // text section has been folded by ICF.
5681 Arm_relobj<big_endian>* arm_relobj =
5682 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5683 const Arm_exidx_input_section* exidx_input_section =
5684 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5685 gold_assert(exidx_input_section != NULL);
5686 unsigned int text_shndx = exidx_input_section->link();
5687 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5689 // Remove this from link.
5690 p->relobj()->set_output_section(p->shndx(), NULL);
5694 // Link exidx output section to the first seen output section and
5695 // set correct entry size.
5696 this->set_link_section(exidx_fixup.first_output_text_section());
5697 this->set_entsize(8);
5699 // Make changes permanent.
5700 this->save_states();
5701 this->set_section_offsets_need_adjustment();
5704 // Arm_relobj methods.
5706 // Determine if an input section is scannable for stub processing. SHDR is
5707 // the header of the section and SHNDX is the section index. OS is the output
5708 // section for the input section and SYMTAB is the global symbol table used to
5709 // look up ICF information.
5711 template<bool big_endian>
5713 Arm_relobj<big_endian>::section_is_scannable(
5714 const elfcpp::Shdr<32, big_endian>& shdr,
5716 const Output_section* os,
5717 const Symbol_table *symtab)
5719 // Skip any empty sections, unallocated sections or sections whose
5720 // type are not SHT_PROGBITS.
5721 if (shdr.get_sh_size() == 0
5722 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
5723 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
5726 // Skip any discarded or ICF'ed sections.
5727 if (os == NULL || symtab->is_section_folded(this, shndx))
5730 // If this requires special offset handling, check to see if it is
5731 // a relaxed section. If this is not, then it is a merged section that
5732 // we cannot handle.
5733 if (this->is_output_section_offset_invalid(shndx))
5735 const Output_relaxed_input_section* poris =
5736 os->find_relaxed_input_section(this, shndx);
5744 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5745 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5747 template<bool big_endian>
5749 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
5750 const elfcpp::Shdr<32, big_endian>& shdr,
5751 const Relobj::Output_sections& out_sections,
5752 const Symbol_table *symtab,
5753 const unsigned char* pshdrs)
5755 unsigned int sh_type = shdr.get_sh_type();
5756 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
5759 // Ignore empty section.
5760 off_t sh_size = shdr.get_sh_size();
5764 // Ignore reloc section with unexpected symbol table. The
5765 // error will be reported in the final link.
5766 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
5769 unsigned int reloc_size;
5770 if (sh_type == elfcpp::SHT_REL)
5771 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5773 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5775 // Ignore reloc section with unexpected entsize or uneven size.
5776 // The error will be reported in the final link.
5777 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
5780 // Ignore reloc section with bad info. This error will be
5781 // reported in the final link.
5782 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5783 if (index >= this->shnum())
5786 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5787 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
5788 return this->section_is_scannable(text_shdr, index,
5789 out_sections[index], symtab);
5792 // Return the output address of either a plain input section or a relaxed
5793 // input section. SHNDX is the section index. We define and use this
5794 // instead of calling Output_section::output_address because that is slow
5795 // for large output.
5797 template<bool big_endian>
5799 Arm_relobj<big_endian>::simple_input_section_output_address(
5803 if (this->is_output_section_offset_invalid(shndx))
5805 const Output_relaxed_input_section* poris =
5806 os->find_relaxed_input_section(this, shndx);
5807 // We do not handle merged sections here.
5808 gold_assert(poris != NULL);
5809 return poris->address();
5812 return os->address() + this->get_output_section_offset(shndx);
5815 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
5816 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5818 template<bool big_endian>
5820 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
5821 const elfcpp::Shdr<32, big_endian>& shdr,
5824 const Symbol_table* symtab)
5826 if (!this->section_is_scannable(shdr, shndx, os, symtab))
5829 // If the section does not cross any 4K-boundaries, it does not need to
5831 Arm_address address = this->simple_input_section_output_address(shndx, os);
5832 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
5838 // Scan a section for Cortex-A8 workaround.
5840 template<bool big_endian>
5842 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
5843 const elfcpp::Shdr<32, big_endian>& shdr,
5846 Target_arm<big_endian>* arm_target)
5848 // Look for the first mapping symbol in this section. It should be
5850 Mapping_symbol_position section_start(shndx, 0);
5851 typename Mapping_symbols_info::const_iterator p =
5852 this->mapping_symbols_info_.lower_bound(section_start);
5854 // There are no mapping symbols for this section. Treat it as a data-only
5856 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
5859 Arm_address output_address =
5860 this->simple_input_section_output_address(shndx, os);
5862 // Get the section contents.
5863 section_size_type input_view_size = 0;
5864 const unsigned char* input_view =
5865 this->section_contents(shndx, &input_view_size, false);
5867 // We need to go through the mapping symbols to determine what to
5868 // scan. There are two reasons. First, we should look at THUMB code and
5869 // THUMB code only. Second, we only want to look at the 4K-page boundary
5870 // to speed up the scanning.
5872 while (p != this->mapping_symbols_info_.end()
5873 && p->first.first == shndx)
5875 typename Mapping_symbols_info::const_iterator next =
5876 this->mapping_symbols_info_.upper_bound(p->first);
5878 // Only scan part of a section with THUMB code.
5879 if (p->second == 't')
5881 // Determine the end of this range.
5882 section_size_type span_start =
5883 convert_to_section_size_type(p->first.second);
5884 section_size_type span_end;
5885 if (next != this->mapping_symbols_info_.end()
5886 && next->first.first == shndx)
5887 span_end = convert_to_section_size_type(next->first.second);
5889 span_end = convert_to_section_size_type(shdr.get_sh_size());
5891 if (((span_start + output_address) & ~0xfffUL)
5892 != ((span_end + output_address - 1) & ~0xfffUL))
5894 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
5895 span_start, span_end,
5905 // Scan relocations for stub generation.
5907 template<bool big_endian>
5909 Arm_relobj<big_endian>::scan_sections_for_stubs(
5910 Target_arm<big_endian>* arm_target,
5911 const Symbol_table* symtab,
5912 const Layout* layout)
5914 unsigned int shnum = this->shnum();
5915 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5917 // Read the section headers.
5918 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
5922 // To speed up processing, we set up hash tables for fast lookup of
5923 // input offsets to output addresses.
5924 this->initialize_input_to_output_maps();
5926 const Relobj::Output_sections& out_sections(this->output_sections());
5928 Relocate_info<32, big_endian> relinfo;
5929 relinfo.symtab = symtab;
5930 relinfo.layout = layout;
5931 relinfo.object = this;
5933 // Do relocation stubs scanning.
5934 const unsigned char* p = pshdrs + shdr_size;
5935 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
5937 const elfcpp::Shdr<32, big_endian> shdr(p);
5938 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
5941 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5942 Arm_address output_offset = this->get_output_section_offset(index);
5943 Arm_address output_address;
5944 if(output_offset != invalid_address)
5945 output_address = out_sections[index]->address() + output_offset;
5948 // Currently this only happens for a relaxed section.
5949 const Output_relaxed_input_section* poris =
5950 out_sections[index]->find_relaxed_input_section(this, index);
5951 gold_assert(poris != NULL);
5952 output_address = poris->address();
5955 // Get the relocations.
5956 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
5960 // Get the section contents. This does work for the case in which
5961 // we modify the contents of an input section. We need to pass the
5962 // output view under such circumstances.
5963 section_size_type input_view_size = 0;
5964 const unsigned char* input_view =
5965 this->section_contents(index, &input_view_size, false);
5967 relinfo.reloc_shndx = i;
5968 relinfo.data_shndx = index;
5969 unsigned int sh_type = shdr.get_sh_type();
5970 unsigned int reloc_size;
5971 if (sh_type == elfcpp::SHT_REL)
5972 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5974 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5976 Output_section* os = out_sections[index];
5977 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
5978 shdr.get_sh_size() / reloc_size,
5980 output_offset == invalid_address,
5981 input_view, output_address,
5986 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
5987 // after its relocation section, if there is one, is processed for
5988 // relocation stubs. Merging this loop with the one above would have been
5989 // complicated since we would have had to make sure that relocation stub
5990 // scanning is done first.
5991 if (arm_target->fix_cortex_a8())
5993 const unsigned char* p = pshdrs + shdr_size;
5994 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
5996 const elfcpp::Shdr<32, big_endian> shdr(p);
5997 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
6000 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
6005 // After we've done the relocations, we release the hash tables,
6006 // since we no longer need them.
6007 this->free_input_to_output_maps();
6010 // Count the local symbols. The ARM backend needs to know if a symbol
6011 // is a THUMB function or not. For global symbols, it is easy because
6012 // the Symbol object keeps the ELF symbol type. For local symbol it is
6013 // harder because we cannot access this information. So we override the
6014 // do_count_local_symbol in parent and scan local symbols to mark
6015 // THUMB functions. This is not the most efficient way but I do not want to
6016 // slow down other ports by calling a per symbol targer hook inside
6017 // Sized_relobj<size, big_endian>::do_count_local_symbols.
6019 template<bool big_endian>
6021 Arm_relobj<big_endian>::do_count_local_symbols(
6022 Stringpool_template<char>* pool,
6023 Stringpool_template<char>* dynpool)
6025 // We need to fix-up the values of any local symbols whose type are
6028 // Ask parent to count the local symbols.
6029 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
6030 const unsigned int loccount = this->local_symbol_count();
6034 // Intialize the thumb function bit-vector.
6035 std::vector<bool> empty_vector(loccount, false);
6036 this->local_symbol_is_thumb_function_.swap(empty_vector);
6038 // Read the symbol table section header.
6039 const unsigned int symtab_shndx = this->symtab_shndx();
6040 elfcpp::Shdr<32, big_endian>
6041 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6042 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6044 // Read the local symbols.
6045 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6046 gold_assert(loccount == symtabshdr.get_sh_info());
6047 off_t locsize = loccount * sym_size;
6048 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6049 locsize, true, true);
6051 // For mapping symbol processing, we need to read the symbol names.
6052 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6053 if (strtab_shndx >= this->shnum())
6055 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6059 elfcpp::Shdr<32, big_endian>
6060 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6061 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6063 this->error(_("symbol table name section has wrong type: %u"),
6064 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6067 const char* pnames =
6068 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6069 strtabshdr.get_sh_size(),
6072 // Loop over the local symbols and mark any local symbols pointing
6073 // to THUMB functions.
6075 // Skip the first dummy symbol.
6077 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
6078 this->local_values();
6079 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6081 elfcpp::Sym<32, big_endian> sym(psyms);
6082 elfcpp::STT st_type = sym.get_st_type();
6083 Symbol_value<32>& lv((*plocal_values)[i]);
6084 Arm_address input_value = lv.input_value();
6086 // Check to see if this is a mapping symbol.
6087 const char* sym_name = pnames + sym.get_st_name();
6088 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6090 unsigned int input_shndx = sym.get_st_shndx();
6092 // Strip of LSB in case this is a THUMB symbol.
6093 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6094 this->mapping_symbols_info_[msp] = sym_name[1];
6097 if (st_type == elfcpp::STT_ARM_TFUNC
6098 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6100 // This is a THUMB function. Mark this and canonicalize the
6101 // symbol value by setting LSB.
6102 this->local_symbol_is_thumb_function_[i] = true;
6103 if ((input_value & 1) == 0)
6104 lv.set_input_value(input_value | 1);
6109 // Relocate sections.
6110 template<bool big_endian>
6112 Arm_relobj<big_endian>::do_relocate_sections(
6113 const Symbol_table* symtab,
6114 const Layout* layout,
6115 const unsigned char* pshdrs,
6116 typename Sized_relobj<32, big_endian>::Views* pviews)
6118 // Call parent to relocate sections.
6119 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
6122 // We do not generate stubs if doing a relocatable link.
6123 if (parameters->options().relocatable())
6126 // Relocate stub tables.
6127 unsigned int shnum = this->shnum();
6129 Target_arm<big_endian>* arm_target =
6130 Target_arm<big_endian>::default_target();
6132 Relocate_info<32, big_endian> relinfo;
6133 relinfo.symtab = symtab;
6134 relinfo.layout = layout;
6135 relinfo.object = this;
6137 for (unsigned int i = 1; i < shnum; ++i)
6139 Arm_input_section<big_endian>* arm_input_section =
6140 arm_target->find_arm_input_section(this, i);
6142 if (arm_input_section != NULL
6143 && arm_input_section->is_stub_table_owner()
6144 && !arm_input_section->stub_table()->empty())
6146 // We cannot discard a section if it owns a stub table.
6147 Output_section* os = this->output_section(i);
6148 gold_assert(os != NULL);
6150 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6151 relinfo.reloc_shdr = NULL;
6152 relinfo.data_shndx = i;
6153 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6155 gold_assert((*pviews)[i].view != NULL);
6157 // We are passed the output section view. Adjust it to cover the
6159 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6160 gold_assert((stub_table->address() >= (*pviews)[i].address)
6161 && ((stub_table->address() + stub_table->data_size())
6162 <= (*pviews)[i].address + (*pviews)[i].view_size));
6164 off_t offset = stub_table->address() - (*pviews)[i].address;
6165 unsigned char* view = (*pviews)[i].view + offset;
6166 Arm_address address = stub_table->address();
6167 section_size_type view_size = stub_table->data_size();
6169 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6173 // Apply Cortex A8 workaround if applicable.
6174 if (this->section_has_cortex_a8_workaround(i))
6176 unsigned char* view = (*pviews)[i].view;
6177 Arm_address view_address = (*pviews)[i].address;
6178 section_size_type view_size = (*pviews)[i].view_size;
6179 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6181 // Adjust view to cover section.
6182 Output_section* os = this->output_section(i);
6183 gold_assert(os != NULL);
6184 Arm_address section_address =
6185 this->simple_input_section_output_address(i, os);
6186 uint64_t section_size = this->section_size(i);
6188 gold_assert(section_address >= view_address
6189 && ((section_address + section_size)
6190 <= (view_address + view_size)));
6192 unsigned char* section_view = view + (section_address - view_address);
6194 // Apply the Cortex-A8 workaround to the output address range
6195 // corresponding to this input section.
6196 stub_table->apply_cortex_a8_workaround_to_address_range(
6205 // Find the linked text section of an EXIDX section by looking the the first
6206 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6207 // must be linked to to its associated code section via the sh_link field of
6208 // its section header. However, some tools are broken and the link is not
6209 // always set. LD just drops such an EXIDX section silently, causing the
6210 // associated code not unwindabled. Here we try a little bit harder to
6211 // discover the linked code section.
6213 // PSHDR points to the section header of a relocation section of an EXIDX
6214 // section. If we can find a linked text section, return true and
6215 // store the text section index in the location PSHNDX. Otherwise
6218 template<bool big_endian>
6220 Arm_relobj<big_endian>::find_linked_text_section(
6221 const unsigned char* pshdr,
6222 const unsigned char* psyms,
6223 unsigned int* pshndx)
6225 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6227 // If there is no relocation, we cannot find the linked text section.
6229 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6230 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6232 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6233 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6235 // Get the relocations.
6236 const unsigned char* prelocs =
6237 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6239 // Find the REL31 relocation for the first word of the first EXIDX entry.
6240 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6242 Arm_address r_offset;
6243 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6244 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6246 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6247 r_info = reloc.get_r_info();
6248 r_offset = reloc.get_r_offset();
6252 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6253 r_info = reloc.get_r_info();
6254 r_offset = reloc.get_r_offset();
6257 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6258 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6261 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6263 || r_sym >= this->local_symbol_count()
6267 // This is the relocation for the first word of the first EXIDX entry.
6268 // We expect to see a local section symbol.
6269 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6270 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6271 if (sym.get_st_type() == elfcpp::STT_SECTION)
6273 *pshndx = this->adjust_shndx(sym.get_st_shndx());
6283 // Make an EXIDX input section object for an EXIDX section whose index is
6284 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6285 // is the section index of the linked text section.
6287 template<bool big_endian>
6289 Arm_relobj<big_endian>::make_exidx_input_section(
6291 const elfcpp::Shdr<32, big_endian>& shdr,
6292 unsigned int text_shndx)
6294 // Issue an error and ignore this EXIDX section if it points to a text
6295 // section already has an EXIDX section.
6296 if (this->exidx_section_map_[text_shndx] != NULL)
6298 gold_error(_("EXIDX sections %u and %u both link to text section %u "
6300 shndx, this->exidx_section_map_[text_shndx]->shndx(),
6301 text_shndx, this->name().c_str());
6305 // Create an Arm_exidx_input_section object for this EXIDX section.
6306 Arm_exidx_input_section* exidx_input_section =
6307 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6308 shdr.get_sh_addralign());
6309 this->exidx_section_map_[text_shndx] = exidx_input_section;
6311 // Also map the EXIDX section index to this.
6312 gold_assert(this->exidx_section_map_[shndx] == NULL);
6313 this->exidx_section_map_[shndx] = exidx_input_section;
6316 // Read the symbol information.
6318 template<bool big_endian>
6320 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6322 // Call parent class to read symbol information.
6323 Sized_relobj<32, big_endian>::do_read_symbols(sd);
6325 // Read processor-specific flags in ELF file header.
6326 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6327 elfcpp::Elf_sizes<32>::ehdr_size,
6329 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6330 this->processor_specific_flags_ = ehdr.get_e_flags();
6332 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6334 std::vector<unsigned int> deferred_exidx_sections;
6335 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6336 const unsigned char* pshdrs = sd->section_headers->data();
6337 const unsigned char *ps = pshdrs + shdr_size;
6338 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6340 elfcpp::Shdr<32, big_endian> shdr(ps);
6341 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6343 gold_assert(this->attributes_section_data_ == NULL);
6344 section_offset_type section_offset = shdr.get_sh_offset();
6345 section_size_type section_size =
6346 convert_to_section_size_type(shdr.get_sh_size());
6347 File_view* view = this->get_lasting_view(section_offset,
6348 section_size, true, false);
6349 this->attributes_section_data_ =
6350 new Attributes_section_data(view->data(), section_size);
6352 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6354 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6355 if (text_shndx >= this->shnum())
6356 gold_error(_("EXIDX section %u linked to invalid section %u"),
6358 else if (text_shndx == elfcpp::SHN_UNDEF)
6359 deferred_exidx_sections.push_back(i);
6361 this->make_exidx_input_section(i, shdr, text_shndx);
6365 // Some tools are broken and they do not set the link of EXIDX sections.
6366 // We look at the first relocation to figure out the linked sections.
6367 if (!deferred_exidx_sections.empty())
6369 // We need to go over the section headers again to find the mapping
6370 // from sections being relocated to their relocation sections. This is
6371 // a bit inefficient as we could do that in the loop above. However,
6372 // we do not expect any deferred EXIDX sections normally. So we do not
6373 // want to slow down the most common path.
6374 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6375 Reloc_map reloc_map;
6376 ps = pshdrs + shdr_size;
6377 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6379 elfcpp::Shdr<32, big_endian> shdr(ps);
6380 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6381 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6383 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6384 if (info_shndx >= this->shnum())
6385 gold_error(_("relocation section %u has invalid info %u"),
6387 Reloc_map::value_type value(info_shndx, i);
6388 std::pair<Reloc_map::iterator, bool> result =
6389 reloc_map.insert(value);
6391 gold_error(_("section %u has multiple relocation sections "
6393 info_shndx, i, reloc_map[info_shndx]);
6397 // Read the symbol table section header.
6398 const unsigned int symtab_shndx = this->symtab_shndx();
6399 elfcpp::Shdr<32, big_endian>
6400 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6401 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6403 // Read the local symbols.
6404 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6405 const unsigned int loccount = this->local_symbol_count();
6406 gold_assert(loccount == symtabshdr.get_sh_info());
6407 off_t locsize = loccount * sym_size;
6408 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6409 locsize, true, true);
6411 // Process the deferred EXIDX sections.
6412 for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6414 unsigned int shndx = deferred_exidx_sections[i];
6415 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6416 unsigned int text_shndx;
6417 Reloc_map::const_iterator it = reloc_map.find(shndx);
6418 if (it != reloc_map.end()
6419 && find_linked_text_section(pshdrs + it->second * shdr_size,
6420 psyms, &text_shndx))
6421 this->make_exidx_input_section(shndx, shdr, text_shndx);
6423 gold_error(_("EXIDX section %u has no linked text section."),
6429 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6430 // sections for unwinding. These sections are referenced implicitly by
6431 // text sections linked in the section headers. If we ignore these implict
6432 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6433 // will be garbage-collected incorrectly. Hence we override the same function
6434 // in the base class to handle these implicit references.
6436 template<bool big_endian>
6438 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6440 Read_relocs_data* rd)
6442 // First, call base class method to process relocations in this object.
6443 Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6445 // If --gc-sections is not specified, there is nothing more to do.
6446 // This happens when --icf is used but --gc-sections is not.
6447 if (!parameters->options().gc_sections())
6450 unsigned int shnum = this->shnum();
6451 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6452 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6456 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6457 // to these from the linked text sections.
6458 const unsigned char* ps = pshdrs + shdr_size;
6459 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6461 elfcpp::Shdr<32, big_endian> shdr(ps);
6462 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6464 // Found an .ARM.exidx section, add it to the set of reachable
6465 // sections from its linked text section.
6466 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6467 symtab->gc()->add_reference(this, text_shndx, this, i);
6472 // Update output local symbol count. Owing to EXIDX entry merging, some local
6473 // symbols will be removed in output. Adjust output local symbol count
6474 // accordingly. We can only changed the static output local symbol count. It
6475 // is too late to change the dynamic symbols.
6477 template<bool big_endian>
6479 Arm_relobj<big_endian>::update_output_local_symbol_count()
6481 // Caller should check that this needs updating. We want caller checking
6482 // because output_local_symbol_count_needs_update() is most likely inlined.
6483 gold_assert(this->output_local_symbol_count_needs_update_);
6485 gold_assert(this->symtab_shndx() != -1U);
6486 if (this->symtab_shndx() == 0)
6488 // This object has no symbols. Weird but legal.
6492 // Read the symbol table section header.
6493 const unsigned int symtab_shndx = this->symtab_shndx();
6494 elfcpp::Shdr<32, big_endian>
6495 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6496 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6498 // Read the local symbols.
6499 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6500 const unsigned int loccount = this->local_symbol_count();
6501 gold_assert(loccount == symtabshdr.get_sh_info());
6502 off_t locsize = loccount * sym_size;
6503 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6504 locsize, true, true);
6506 // Loop over the local symbols.
6508 typedef typename Sized_relobj<32, big_endian>::Output_sections
6510 const Output_sections& out_sections(this->output_sections());
6511 unsigned int shnum = this->shnum();
6512 unsigned int count = 0;
6513 // Skip the first, dummy, symbol.
6515 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6517 elfcpp::Sym<32, big_endian> sym(psyms);
6519 Symbol_value<32>& lv((*this->local_values())[i]);
6521 // This local symbol was already discarded by do_count_local_symbols.
6522 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6526 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6531 Output_section* os = out_sections[shndx];
6533 // This local symbol no longer has an output section. Discard it.
6536 lv.set_no_output_symtab_entry();
6540 // Currently we only discard parts of EXIDX input sections.
6541 // We explicitly check for a merged EXIDX input section to avoid
6542 // calling Output_section_data::output_offset unless necessary.
6543 if ((this->get_output_section_offset(shndx) == invalid_address)
6544 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6546 section_offset_type output_offset =
6547 os->output_offset(this, shndx, lv.input_value());
6548 if (output_offset == -1)
6550 // This symbol is defined in a part of an EXIDX input section
6551 // that is discarded due to entry merging.
6552 lv.set_no_output_symtab_entry();
6561 this->set_output_local_symbol_count(count);
6562 this->output_local_symbol_count_needs_update_ = false;
6565 // Arm_dynobj methods.
6567 // Read the symbol information.
6569 template<bool big_endian>
6571 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6573 // Call parent class to read symbol information.
6574 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6576 // Read processor-specific flags in ELF file header.
6577 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6578 elfcpp::Elf_sizes<32>::ehdr_size,
6580 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6581 this->processor_specific_flags_ = ehdr.get_e_flags();
6583 // Read the attributes section if there is one.
6584 // We read from the end because gas seems to put it near the end of
6585 // the section headers.
6586 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6587 const unsigned char *ps =
6588 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6589 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6591 elfcpp::Shdr<32, big_endian> shdr(ps);
6592 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6594 section_offset_type section_offset = shdr.get_sh_offset();
6595 section_size_type section_size =
6596 convert_to_section_size_type(shdr.get_sh_size());
6597 File_view* view = this->get_lasting_view(section_offset,
6598 section_size, true, false);
6599 this->attributes_section_data_ =
6600 new Attributes_section_data(view->data(), section_size);
6606 // Stub_addend_reader methods.
6608 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6610 template<bool big_endian>
6611 elfcpp::Elf_types<32>::Elf_Swxword
6612 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
6613 unsigned int r_type,
6614 const unsigned char* view,
6615 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
6617 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
6621 case elfcpp::R_ARM_CALL:
6622 case elfcpp::R_ARM_JUMP24:
6623 case elfcpp::R_ARM_PLT32:
6625 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6626 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6627 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
6628 return utils::sign_extend<26>(val << 2);
6631 case elfcpp::R_ARM_THM_CALL:
6632 case elfcpp::R_ARM_THM_JUMP24:
6633 case elfcpp::R_ARM_THM_XPC22:
6635 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6636 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6637 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6638 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6639 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
6642 case elfcpp::R_ARM_THM_JUMP19:
6644 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6645 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6646 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6647 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6648 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
6656 // Arm_output_data_got methods.
6658 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
6659 // The first one is initialized to be 1, which is the module index for
6660 // the main executable and the second one 0. A reloc of the type
6661 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
6662 // be applied by gold. GSYM is a global symbol.
6664 template<bool big_endian>
6666 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6667 unsigned int got_type,
6670 if (gsym->has_got_offset(got_type))
6673 // We are doing a static link. Just mark it as belong to module 1,
6675 unsigned int got_offset = this->add_constant(1);
6676 gsym->set_got_offset(got_type, got_offset);
6677 got_offset = this->add_constant(0);
6678 this->static_relocs_.push_back(Static_reloc(got_offset,
6679 elfcpp::R_ARM_TLS_DTPOFF32,
6683 // Same as the above but for a local symbol.
6685 template<bool big_endian>
6687 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6688 unsigned int got_type,
6689 Sized_relobj<32, big_endian>* object,
6692 if (object->local_has_got_offset(index, got_type))
6695 // We are doing a static link. Just mark it as belong to module 1,
6697 unsigned int got_offset = this->add_constant(1);
6698 object->set_local_got_offset(index, got_type, got_offset);
6699 got_offset = this->add_constant(0);
6700 this->static_relocs_.push_back(Static_reloc(got_offset,
6701 elfcpp::R_ARM_TLS_DTPOFF32,
6705 template<bool big_endian>
6707 Arm_output_data_got<big_endian>::do_write(Output_file* of)
6709 // Call parent to write out GOT.
6710 Output_data_got<32, big_endian>::do_write(of);
6712 // We are done if there is no fix up.
6713 if (this->static_relocs_.empty())
6716 gold_assert(parameters->doing_static_link());
6718 const off_t offset = this->offset();
6719 const section_size_type oview_size =
6720 convert_to_section_size_type(this->data_size());
6721 unsigned char* const oview = of->get_output_view(offset, oview_size);
6723 Output_segment* tls_segment = this->layout_->tls_segment();
6724 gold_assert(tls_segment != NULL);
6726 // The thread pointer $tp points to the TCB, which is followed by the
6727 // TLS. So we need to adjust $tp relative addressing by this amount.
6728 Arm_address aligned_tcb_size =
6729 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
6731 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
6733 Static_reloc& reloc(this->static_relocs_[i]);
6736 if (!reloc.symbol_is_global())
6738 Sized_relobj<32, big_endian>* object = reloc.relobj();
6739 const Symbol_value<32>* psymval =
6740 reloc.relobj()->local_symbol(reloc.index());
6742 // We are doing static linking. Issue an error and skip this
6743 // relocation if the symbol is undefined or in a discarded_section.
6745 unsigned int shndx = psymval->input_shndx(&is_ordinary);
6746 if ((shndx == elfcpp::SHN_UNDEF)
6748 && shndx != elfcpp::SHN_UNDEF
6749 && !object->is_section_included(shndx)
6750 && !this->symbol_table_->is_section_folded(object, shndx)))
6752 gold_error(_("undefined or discarded local symbol %u from "
6753 " object %s in GOT"),
6754 reloc.index(), reloc.relobj()->name().c_str());
6758 value = psymval->value(object, 0);
6762 const Symbol* gsym = reloc.symbol();
6763 gold_assert(gsym != NULL);
6764 if (gsym->is_forwarder())
6765 gsym = this->symbol_table_->resolve_forwards(gsym);
6767 // We are doing static linking. Issue an error and skip this
6768 // relocation if the symbol is undefined or in a discarded_section
6769 // unless it is a weakly_undefined symbol.
6770 if ((gsym->is_defined_in_discarded_section()
6771 || gsym->is_undefined())
6772 && !gsym->is_weak_undefined())
6774 gold_error(_("undefined or discarded symbol %s in GOT"),
6779 if (!gsym->is_weak_undefined())
6781 const Sized_symbol<32>* sym =
6782 static_cast<const Sized_symbol<32>*>(gsym);
6783 value = sym->value();
6789 unsigned got_offset = reloc.got_offset();
6790 gold_assert(got_offset < oview_size);
6792 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6793 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
6795 switch (reloc.r_type())
6797 case elfcpp::R_ARM_TLS_DTPOFF32:
6800 case elfcpp::R_ARM_TLS_TPOFF32:
6801 x = value + aligned_tcb_size;
6806 elfcpp::Swap<32, big_endian>::writeval(wv, x);
6809 of->write_output_view(offset, oview_size, oview);
6812 // A class to handle the PLT data.
6814 template<bool big_endian>
6815 class Output_data_plt_arm : public Output_section_data
6818 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
6821 Output_data_plt_arm(Layout*, Output_data_space*);
6823 // Add an entry to the PLT.
6825 add_entry(Symbol* gsym);
6827 // Return the .rel.plt section data.
6828 const Reloc_section*
6830 { return this->rel_; }
6834 do_adjust_output_section(Output_section* os);
6836 // Write to a map file.
6838 do_print_to_mapfile(Mapfile* mapfile) const
6839 { mapfile->print_output_data(this, _("** PLT")); }
6842 // Template for the first PLT entry.
6843 static const uint32_t first_plt_entry[5];
6845 // Template for subsequent PLT entries.
6846 static const uint32_t plt_entry[3];
6848 // Set the final size.
6850 set_final_data_size()
6852 this->set_data_size(sizeof(first_plt_entry)
6853 + this->count_ * sizeof(plt_entry));
6856 // Write out the PLT data.
6858 do_write(Output_file*);
6860 // The reloc section.
6861 Reloc_section* rel_;
6862 // The .got.plt section.
6863 Output_data_space* got_plt_;
6864 // The number of PLT entries.
6865 unsigned int count_;
6868 // Create the PLT section. The ordinary .got section is an argument,
6869 // since we need to refer to the start. We also create our own .got
6870 // section just for PLT entries.
6872 template<bool big_endian>
6873 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
6874 Output_data_space* got_plt)
6875 : Output_section_data(4), got_plt_(got_plt), count_(0)
6877 this->rel_ = new Reloc_section(false);
6878 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
6879 elfcpp::SHF_ALLOC, this->rel_, true, false,
6883 template<bool big_endian>
6885 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
6890 // Add an entry to the PLT.
6892 template<bool big_endian>
6894 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
6896 gold_assert(!gsym->has_plt_offset());
6898 // Note that when setting the PLT offset we skip the initial
6899 // reserved PLT entry.
6900 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
6901 + sizeof(first_plt_entry));
6905 section_offset_type got_offset = this->got_plt_->current_data_size();
6907 // Every PLT entry needs a GOT entry which points back to the PLT
6908 // entry (this will be changed by the dynamic linker, normally
6909 // lazily when the function is called).
6910 this->got_plt_->set_current_data_size(got_offset + 4);
6912 // Every PLT entry needs a reloc.
6913 gsym->set_needs_dynsym_entry();
6914 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
6917 // Note that we don't need to save the symbol. The contents of the
6918 // PLT are independent of which symbols are used. The symbols only
6919 // appear in the relocations.
6923 // FIXME: This is not very flexible. Right now this has only been tested
6924 // on armv5te. If we are to support additional architecture features like
6925 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
6927 // The first entry in the PLT.
6928 template<bool big_endian>
6929 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
6931 0xe52de004, // str lr, [sp, #-4]!
6932 0xe59fe004, // ldr lr, [pc, #4]
6933 0xe08fe00e, // add lr, pc, lr
6934 0xe5bef008, // ldr pc, [lr, #8]!
6935 0x00000000, // &GOT[0] - .
6938 // Subsequent entries in the PLT.
6940 template<bool big_endian>
6941 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
6943 0xe28fc600, // add ip, pc, #0xNN00000
6944 0xe28cca00, // add ip, ip, #0xNN000
6945 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
6948 // Write out the PLT. This uses the hand-coded instructions above,
6949 // and adjusts them as needed. This is all specified by the arm ELF
6950 // Processor Supplement.
6952 template<bool big_endian>
6954 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
6956 const off_t offset = this->offset();
6957 const section_size_type oview_size =
6958 convert_to_section_size_type(this->data_size());
6959 unsigned char* const oview = of->get_output_view(offset, oview_size);
6961 const off_t got_file_offset = this->got_plt_->offset();
6962 const section_size_type got_size =
6963 convert_to_section_size_type(this->got_plt_->data_size());
6964 unsigned char* const got_view = of->get_output_view(got_file_offset,
6966 unsigned char* pov = oview;
6968 Arm_address plt_address = this->address();
6969 Arm_address got_address = this->got_plt_->address();
6971 // Write first PLT entry. All but the last word are constants.
6972 const size_t num_first_plt_words = (sizeof(first_plt_entry)
6973 / sizeof(plt_entry[0]));
6974 for (size_t i = 0; i < num_first_plt_words - 1; i++)
6975 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
6976 // Last word in first PLT entry is &GOT[0] - .
6977 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
6978 got_address - (plt_address + 16));
6979 pov += sizeof(first_plt_entry);
6981 unsigned char* got_pov = got_view;
6983 memset(got_pov, 0, 12);
6986 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
6987 unsigned int plt_offset = sizeof(first_plt_entry);
6988 unsigned int plt_rel_offset = 0;
6989 unsigned int got_offset = 12;
6990 const unsigned int count = this->count_;
6991 for (unsigned int i = 0;
6994 pov += sizeof(plt_entry),
6996 plt_offset += sizeof(plt_entry),
6997 plt_rel_offset += rel_size,
7000 // Set and adjust the PLT entry itself.
7001 int32_t offset = ((got_address + got_offset)
7002 - (plt_address + plt_offset + 8));
7004 gold_assert(offset >= 0 && offset < 0x0fffffff);
7005 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
7006 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
7007 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
7008 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
7009 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
7010 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7012 // Set the entry in the GOT.
7013 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7016 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7017 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7019 of->write_output_view(offset, oview_size, oview);
7020 of->write_output_view(got_file_offset, got_size, got_view);
7023 // Create a PLT entry for a global symbol.
7025 template<bool big_endian>
7027 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7030 if (gsym->has_plt_offset())
7033 if (this->plt_ == NULL)
7035 // Create the GOT sections first.
7036 this->got_section(symtab, layout);
7038 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
7039 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7041 | elfcpp::SHF_EXECINSTR),
7042 this->plt_, false, false, false, false);
7044 this->plt_->add_entry(gsym);
7047 // Get the section to use for TLS_DESC relocations.
7049 template<bool big_endian>
7050 typename Target_arm<big_endian>::Reloc_section*
7051 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7053 return this->plt_section()->rel_tls_desc(layout);
7056 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7058 template<bool big_endian>
7060 Target_arm<big_endian>::define_tls_base_symbol(
7061 Symbol_table* symtab,
7064 if (this->tls_base_symbol_defined_)
7067 Output_segment* tls_segment = layout->tls_segment();
7068 if (tls_segment != NULL)
7070 bool is_exec = parameters->options().output_is_executable();
7071 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7072 Symbol_table::PREDEFINED,
7076 elfcpp::STV_HIDDEN, 0,
7078 ? Symbol::SEGMENT_END
7079 : Symbol::SEGMENT_START),
7082 this->tls_base_symbol_defined_ = true;
7085 // Create a GOT entry for the TLS module index.
7087 template<bool big_endian>
7089 Target_arm<big_endian>::got_mod_index_entry(
7090 Symbol_table* symtab,
7092 Sized_relobj<32, big_endian>* object)
7094 if (this->got_mod_index_offset_ == -1U)
7096 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7097 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7098 unsigned int got_offset;
7099 if (!parameters->doing_static_link())
7101 got_offset = got->add_constant(0);
7102 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7103 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7108 // We are doing a static link. Just mark it as belong to module 1,
7110 got_offset = got->add_constant(1);
7113 got->add_constant(0);
7114 this->got_mod_index_offset_ = got_offset;
7116 return this->got_mod_index_offset_;
7119 // Optimize the TLS relocation type based on what we know about the
7120 // symbol. IS_FINAL is true if the final address of this symbol is
7121 // known at link time.
7123 template<bool big_endian>
7124 tls::Tls_optimization
7125 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7127 // FIXME: Currently we do not do any TLS optimization.
7128 return tls::TLSOPT_NONE;
7131 // Report an unsupported relocation against a local symbol.
7133 template<bool big_endian>
7135 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7136 Sized_relobj<32, big_endian>* object,
7137 unsigned int r_type)
7139 gold_error(_("%s: unsupported reloc %u against local symbol"),
7140 object->name().c_str(), r_type);
7143 // We are about to emit a dynamic relocation of type R_TYPE. If the
7144 // dynamic linker does not support it, issue an error. The GNU linker
7145 // only issues a non-PIC error for an allocated read-only section.
7146 // Here we know the section is allocated, but we don't know that it is
7147 // read-only. But we check for all the relocation types which the
7148 // glibc dynamic linker supports, so it seems appropriate to issue an
7149 // error even if the section is not read-only.
7151 template<bool big_endian>
7153 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7154 unsigned int r_type)
7158 // These are the relocation types supported by glibc for ARM.
7159 case elfcpp::R_ARM_RELATIVE:
7160 case elfcpp::R_ARM_COPY:
7161 case elfcpp::R_ARM_GLOB_DAT:
7162 case elfcpp::R_ARM_JUMP_SLOT:
7163 case elfcpp::R_ARM_ABS32:
7164 case elfcpp::R_ARM_ABS32_NOI:
7165 case elfcpp::R_ARM_PC24:
7166 // FIXME: The following 3 types are not supported by Android's dynamic
7168 case elfcpp::R_ARM_TLS_DTPMOD32:
7169 case elfcpp::R_ARM_TLS_DTPOFF32:
7170 case elfcpp::R_ARM_TLS_TPOFF32:
7175 // This prevents us from issuing more than one error per reloc
7176 // section. But we can still wind up issuing more than one
7177 // error per object file.
7178 if (this->issued_non_pic_error_)
7180 const Arm_reloc_property* reloc_property =
7181 arm_reloc_property_table->get_reloc_property(r_type);
7182 gold_assert(reloc_property != NULL);
7183 object->error(_("requires unsupported dynamic reloc %s; "
7184 "recompile with -fPIC"),
7185 reloc_property->name().c_str());
7186 this->issued_non_pic_error_ = true;
7190 case elfcpp::R_ARM_NONE:
7195 // Scan a relocation for a local symbol.
7196 // FIXME: This only handles a subset of relocation types used by Android
7197 // on ARM v5te devices.
7199 template<bool big_endian>
7201 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7204 Sized_relobj<32, big_endian>* object,
7205 unsigned int data_shndx,
7206 Output_section* output_section,
7207 const elfcpp::Rel<32, big_endian>& reloc,
7208 unsigned int r_type,
7209 const elfcpp::Sym<32, big_endian>& lsym)
7211 r_type = get_real_reloc_type(r_type);
7214 case elfcpp::R_ARM_NONE:
7215 case elfcpp::R_ARM_V4BX:
7216 case elfcpp::R_ARM_GNU_VTENTRY:
7217 case elfcpp::R_ARM_GNU_VTINHERIT:
7220 case elfcpp::R_ARM_ABS32:
7221 case elfcpp::R_ARM_ABS32_NOI:
7222 // If building a shared library (or a position-independent
7223 // executable), we need to create a dynamic relocation for
7224 // this location. The relocation applied at link time will
7225 // apply the link-time value, so we flag the location with
7226 // an R_ARM_RELATIVE relocation so the dynamic loader can
7227 // relocate it easily.
7228 if (parameters->options().output_is_position_independent())
7230 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7231 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7232 // If we are to add more other reloc types than R_ARM_ABS32,
7233 // we need to add check_non_pic(object, r_type) here.
7234 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7235 output_section, data_shndx,
7236 reloc.get_r_offset());
7240 case elfcpp::R_ARM_ABS16:
7241 case elfcpp::R_ARM_ABS12:
7242 case elfcpp::R_ARM_THM_ABS5:
7243 case elfcpp::R_ARM_ABS8:
7244 case elfcpp::R_ARM_BASE_ABS:
7245 case elfcpp::R_ARM_MOVW_ABS_NC:
7246 case elfcpp::R_ARM_MOVT_ABS:
7247 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7248 case elfcpp::R_ARM_THM_MOVT_ABS:
7249 // If building a shared library (or a position-independent
7250 // executable), we need to create a dynamic relocation for
7251 // this location. Because the addend needs to remain in the
7252 // data section, we need to be careful not to apply this
7253 // relocation statically.
7254 if (parameters->options().output_is_position_independent())
7256 check_non_pic(object, r_type);
7257 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7258 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7259 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7260 rel_dyn->add_local(object, r_sym, r_type, output_section,
7261 data_shndx, reloc.get_r_offset());
7264 gold_assert(lsym.get_st_value() == 0);
7265 unsigned int shndx = lsym.get_st_shndx();
7267 shndx = object->adjust_sym_shndx(r_sym, shndx,
7270 object->error(_("section symbol %u has bad shndx %u"),
7273 rel_dyn->add_local_section(object, shndx,
7274 r_type, output_section,
7275 data_shndx, reloc.get_r_offset());
7280 case elfcpp::R_ARM_PC24:
7281 case elfcpp::R_ARM_REL32:
7282 case elfcpp::R_ARM_LDR_PC_G0:
7283 case elfcpp::R_ARM_SBREL32:
7284 case elfcpp::R_ARM_THM_CALL:
7285 case elfcpp::R_ARM_THM_PC8:
7286 case elfcpp::R_ARM_BASE_PREL:
7287 case elfcpp::R_ARM_PLT32:
7288 case elfcpp::R_ARM_CALL:
7289 case elfcpp::R_ARM_JUMP24:
7290 case elfcpp::R_ARM_THM_JUMP24:
7291 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7292 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7293 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7294 case elfcpp::R_ARM_SBREL31:
7295 case elfcpp::R_ARM_PREL31:
7296 case elfcpp::R_ARM_MOVW_PREL_NC:
7297 case elfcpp::R_ARM_MOVT_PREL:
7298 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7299 case elfcpp::R_ARM_THM_MOVT_PREL:
7300 case elfcpp::R_ARM_THM_JUMP19:
7301 case elfcpp::R_ARM_THM_JUMP6:
7302 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7303 case elfcpp::R_ARM_THM_PC12:
7304 case elfcpp::R_ARM_REL32_NOI:
7305 case elfcpp::R_ARM_ALU_PC_G0_NC:
7306 case elfcpp::R_ARM_ALU_PC_G0:
7307 case elfcpp::R_ARM_ALU_PC_G1_NC:
7308 case elfcpp::R_ARM_ALU_PC_G1:
7309 case elfcpp::R_ARM_ALU_PC_G2:
7310 case elfcpp::R_ARM_LDR_PC_G1:
7311 case elfcpp::R_ARM_LDR_PC_G2:
7312 case elfcpp::R_ARM_LDRS_PC_G0:
7313 case elfcpp::R_ARM_LDRS_PC_G1:
7314 case elfcpp::R_ARM_LDRS_PC_G2:
7315 case elfcpp::R_ARM_LDC_PC_G0:
7316 case elfcpp::R_ARM_LDC_PC_G1:
7317 case elfcpp::R_ARM_LDC_PC_G2:
7318 case elfcpp::R_ARM_ALU_SB_G0_NC:
7319 case elfcpp::R_ARM_ALU_SB_G0:
7320 case elfcpp::R_ARM_ALU_SB_G1_NC:
7321 case elfcpp::R_ARM_ALU_SB_G1:
7322 case elfcpp::R_ARM_ALU_SB_G2:
7323 case elfcpp::R_ARM_LDR_SB_G0:
7324 case elfcpp::R_ARM_LDR_SB_G1:
7325 case elfcpp::R_ARM_LDR_SB_G2:
7326 case elfcpp::R_ARM_LDRS_SB_G0:
7327 case elfcpp::R_ARM_LDRS_SB_G1:
7328 case elfcpp::R_ARM_LDRS_SB_G2:
7329 case elfcpp::R_ARM_LDC_SB_G0:
7330 case elfcpp::R_ARM_LDC_SB_G1:
7331 case elfcpp::R_ARM_LDC_SB_G2:
7332 case elfcpp::R_ARM_MOVW_BREL_NC:
7333 case elfcpp::R_ARM_MOVT_BREL:
7334 case elfcpp::R_ARM_MOVW_BREL:
7335 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7336 case elfcpp::R_ARM_THM_MOVT_BREL:
7337 case elfcpp::R_ARM_THM_MOVW_BREL:
7338 case elfcpp::R_ARM_THM_JUMP11:
7339 case elfcpp::R_ARM_THM_JUMP8:
7340 // We don't need to do anything for a relative addressing relocation
7341 // against a local symbol if it does not reference the GOT.
7344 case elfcpp::R_ARM_GOTOFF32:
7345 case elfcpp::R_ARM_GOTOFF12:
7346 // We need a GOT section:
7347 target->got_section(symtab, layout);
7350 case elfcpp::R_ARM_GOT_BREL:
7351 case elfcpp::R_ARM_GOT_PREL:
7353 // The symbol requires a GOT entry.
7354 Arm_output_data_got<big_endian>* got =
7355 target->got_section(symtab, layout);
7356 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7357 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
7359 // If we are generating a shared object, we need to add a
7360 // dynamic RELATIVE relocation for this symbol's GOT entry.
7361 if (parameters->options().output_is_position_independent())
7363 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7364 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7365 rel_dyn->add_local_relative(
7366 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
7367 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
7373 case elfcpp::R_ARM_TARGET1:
7374 case elfcpp::R_ARM_TARGET2:
7375 // This should have been mapped to another type already.
7377 case elfcpp::R_ARM_COPY:
7378 case elfcpp::R_ARM_GLOB_DAT:
7379 case elfcpp::R_ARM_JUMP_SLOT:
7380 case elfcpp::R_ARM_RELATIVE:
7381 // These are relocations which should only be seen by the
7382 // dynamic linker, and should never be seen here.
7383 gold_error(_("%s: unexpected reloc %u in object file"),
7384 object->name().c_str(), r_type);
7388 // These are initial TLS relocs, which are expected when
7390 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7391 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7392 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7393 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7394 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7396 bool output_is_shared = parameters->options().shared();
7397 const tls::Tls_optimization optimized_type
7398 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
7402 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7403 if (optimized_type == tls::TLSOPT_NONE)
7405 // Create a pair of GOT entries for the module index and
7406 // dtv-relative offset.
7407 Arm_output_data_got<big_endian>* got
7408 = target->got_section(symtab, layout);
7409 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7410 unsigned int shndx = lsym.get_st_shndx();
7412 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
7415 object->error(_("local symbol %u has bad shndx %u"),
7420 if (!parameters->doing_static_link())
7421 got->add_local_pair_with_rel(object, r_sym, shndx,
7423 target->rel_dyn_section(layout),
7424 elfcpp::R_ARM_TLS_DTPMOD32, 0);
7426 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
7430 // FIXME: TLS optimization not supported yet.
7434 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7435 if (optimized_type == tls::TLSOPT_NONE)
7437 // Create a GOT entry for the module index.
7438 target->got_mod_index_entry(symtab, layout, object);
7441 // FIXME: TLS optimization not supported yet.
7445 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7448 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7449 layout->set_has_static_tls();
7450 if (optimized_type == tls::TLSOPT_NONE)
7452 // Create a GOT entry for the tp-relative offset.
7453 Arm_output_data_got<big_endian>* got
7454 = target->got_section(symtab, layout);
7455 unsigned int r_sym =
7456 elfcpp::elf_r_sym<32>(reloc.get_r_info());
7457 if (!parameters->doing_static_link())
7458 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
7459 target->rel_dyn_section(layout),
7460 elfcpp::R_ARM_TLS_TPOFF32);
7461 else if (!object->local_has_got_offset(r_sym,
7462 GOT_TYPE_TLS_OFFSET))
7464 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
7465 unsigned int got_offset =
7466 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
7467 got->add_static_reloc(got_offset,
7468 elfcpp::R_ARM_TLS_TPOFF32, object,
7473 // FIXME: TLS optimization not supported yet.
7477 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7478 layout->set_has_static_tls();
7479 if (output_is_shared)
7481 // We need to create a dynamic relocation.
7482 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7483 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7484 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7485 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
7486 output_section, data_shndx,
7487 reloc.get_r_offset());
7498 unsupported_reloc_local(object, r_type);
7503 // Report an unsupported relocation against a global symbol.
7505 template<bool big_endian>
7507 Target_arm<big_endian>::Scan::unsupported_reloc_global(
7508 Sized_relobj<32, big_endian>* object,
7509 unsigned int r_type,
7512 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
7513 object->name().c_str(), r_type, gsym->demangled_name().c_str());
7516 // Scan a relocation for a global symbol.
7518 template<bool big_endian>
7520 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
7523 Sized_relobj<32, big_endian>* object,
7524 unsigned int data_shndx,
7525 Output_section* output_section,
7526 const elfcpp::Rel<32, big_endian>& reloc,
7527 unsigned int r_type,
7530 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
7531 // section. We check here to avoid creating a dynamic reloc against
7532 // _GLOBAL_OFFSET_TABLE_.
7533 if (!target->has_got_section()
7534 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7535 target->got_section(symtab, layout);
7537 r_type = get_real_reloc_type(r_type);
7540 case elfcpp::R_ARM_NONE:
7541 case elfcpp::R_ARM_V4BX:
7542 case elfcpp::R_ARM_GNU_VTENTRY:
7543 case elfcpp::R_ARM_GNU_VTINHERIT:
7546 case elfcpp::R_ARM_ABS32:
7547 case elfcpp::R_ARM_ABS16:
7548 case elfcpp::R_ARM_ABS12:
7549 case elfcpp::R_ARM_THM_ABS5:
7550 case elfcpp::R_ARM_ABS8:
7551 case elfcpp::R_ARM_BASE_ABS:
7552 case elfcpp::R_ARM_MOVW_ABS_NC:
7553 case elfcpp::R_ARM_MOVT_ABS:
7554 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7555 case elfcpp::R_ARM_THM_MOVT_ABS:
7556 case elfcpp::R_ARM_ABS32_NOI:
7557 // Absolute addressing relocations.
7559 // Make a PLT entry if necessary.
7560 if (this->symbol_needs_plt_entry(gsym))
7562 target->make_plt_entry(symtab, layout, gsym);
7563 // Since this is not a PC-relative relocation, we may be
7564 // taking the address of a function. In that case we need to
7565 // set the entry in the dynamic symbol table to the address of
7567 if (gsym->is_from_dynobj() && !parameters->options().shared())
7568 gsym->set_needs_dynsym_value();
7570 // Make a dynamic relocation if necessary.
7571 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
7573 if (gsym->may_need_copy_reloc())
7575 target->copy_reloc(symtab, layout, object,
7576 data_shndx, output_section, gsym, reloc);
7578 else if ((r_type == elfcpp::R_ARM_ABS32
7579 || r_type == elfcpp::R_ARM_ABS32_NOI)
7580 && gsym->can_use_relative_reloc(false))
7582 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7583 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
7584 output_section, object,
7585 data_shndx, reloc.get_r_offset());
7589 check_non_pic(object, r_type);
7590 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7591 rel_dyn->add_global(gsym, r_type, output_section, object,
7592 data_shndx, reloc.get_r_offset());
7598 case elfcpp::R_ARM_GOTOFF32:
7599 case elfcpp::R_ARM_GOTOFF12:
7600 // We need a GOT section.
7601 target->got_section(symtab, layout);
7604 case elfcpp::R_ARM_REL32:
7605 case elfcpp::R_ARM_LDR_PC_G0:
7606 case elfcpp::R_ARM_SBREL32:
7607 case elfcpp::R_ARM_THM_PC8:
7608 case elfcpp::R_ARM_BASE_PREL:
7609 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7610 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7611 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7612 case elfcpp::R_ARM_MOVW_PREL_NC:
7613 case elfcpp::R_ARM_MOVT_PREL:
7614 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7615 case elfcpp::R_ARM_THM_MOVT_PREL:
7616 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7617 case elfcpp::R_ARM_THM_PC12:
7618 case elfcpp::R_ARM_REL32_NOI:
7619 case elfcpp::R_ARM_ALU_PC_G0_NC:
7620 case elfcpp::R_ARM_ALU_PC_G0:
7621 case elfcpp::R_ARM_ALU_PC_G1_NC:
7622 case elfcpp::R_ARM_ALU_PC_G1:
7623 case elfcpp::R_ARM_ALU_PC_G2:
7624 case elfcpp::R_ARM_LDR_PC_G1:
7625 case elfcpp::R_ARM_LDR_PC_G2:
7626 case elfcpp::R_ARM_LDRS_PC_G0:
7627 case elfcpp::R_ARM_LDRS_PC_G1:
7628 case elfcpp::R_ARM_LDRS_PC_G2:
7629 case elfcpp::R_ARM_LDC_PC_G0:
7630 case elfcpp::R_ARM_LDC_PC_G1:
7631 case elfcpp::R_ARM_LDC_PC_G2:
7632 case elfcpp::R_ARM_ALU_SB_G0_NC:
7633 case elfcpp::R_ARM_ALU_SB_G0:
7634 case elfcpp::R_ARM_ALU_SB_G1_NC:
7635 case elfcpp::R_ARM_ALU_SB_G1:
7636 case elfcpp::R_ARM_ALU_SB_G2:
7637 case elfcpp::R_ARM_LDR_SB_G0:
7638 case elfcpp::R_ARM_LDR_SB_G1:
7639 case elfcpp::R_ARM_LDR_SB_G2:
7640 case elfcpp::R_ARM_LDRS_SB_G0:
7641 case elfcpp::R_ARM_LDRS_SB_G1:
7642 case elfcpp::R_ARM_LDRS_SB_G2:
7643 case elfcpp::R_ARM_LDC_SB_G0:
7644 case elfcpp::R_ARM_LDC_SB_G1:
7645 case elfcpp::R_ARM_LDC_SB_G2:
7646 case elfcpp::R_ARM_MOVW_BREL_NC:
7647 case elfcpp::R_ARM_MOVT_BREL:
7648 case elfcpp::R_ARM_MOVW_BREL:
7649 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7650 case elfcpp::R_ARM_THM_MOVT_BREL:
7651 case elfcpp::R_ARM_THM_MOVW_BREL:
7652 // Relative addressing relocations.
7654 // Make a dynamic relocation if necessary.
7655 int flags = Symbol::NON_PIC_REF;
7656 if (gsym->needs_dynamic_reloc(flags))
7658 if (target->may_need_copy_reloc(gsym))
7660 target->copy_reloc(symtab, layout, object,
7661 data_shndx, output_section, gsym, reloc);
7665 check_non_pic(object, r_type);
7666 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7667 rel_dyn->add_global(gsym, r_type, output_section, object,
7668 data_shndx, reloc.get_r_offset());
7674 case elfcpp::R_ARM_PC24:
7675 case elfcpp::R_ARM_THM_CALL:
7676 case elfcpp::R_ARM_PLT32:
7677 case elfcpp::R_ARM_CALL:
7678 case elfcpp::R_ARM_JUMP24:
7679 case elfcpp::R_ARM_THM_JUMP24:
7680 case elfcpp::R_ARM_SBREL31:
7681 case elfcpp::R_ARM_PREL31:
7682 case elfcpp::R_ARM_THM_JUMP19:
7683 case elfcpp::R_ARM_THM_JUMP6:
7684 case elfcpp::R_ARM_THM_JUMP11:
7685 case elfcpp::R_ARM_THM_JUMP8:
7686 // All the relocation above are branches except for the PREL31 ones.
7687 // A PREL31 relocation can point to a personality function in a shared
7688 // library. In that case we want to use a PLT because we want to
7689 // call the personality routine and the dyanmic linkers we care about
7690 // do not support dynamic PREL31 relocations. An REL31 relocation may
7691 // point to a function whose unwinding behaviour is being described but
7692 // we will not mistakenly generate a PLT for that because we should use
7693 // a local section symbol.
7695 // If the symbol is fully resolved, this is just a relative
7696 // local reloc. Otherwise we need a PLT entry.
7697 if (gsym->final_value_is_known())
7699 // If building a shared library, we can also skip the PLT entry
7700 // if the symbol is defined in the output file and is protected
7702 if (gsym->is_defined()
7703 && !gsym->is_from_dynobj()
7704 && !gsym->is_preemptible())
7706 target->make_plt_entry(symtab, layout, gsym);
7709 case elfcpp::R_ARM_GOT_BREL:
7710 case elfcpp::R_ARM_GOT_ABS:
7711 case elfcpp::R_ARM_GOT_PREL:
7713 // The symbol requires a GOT entry.
7714 Arm_output_data_got<big_endian>* got =
7715 target->got_section(symtab, layout);
7716 if (gsym->final_value_is_known())
7717 got->add_global(gsym, GOT_TYPE_STANDARD);
7720 // If this symbol is not fully resolved, we need to add a
7721 // GOT entry with a dynamic relocation.
7722 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7723 if (gsym->is_from_dynobj()
7724 || gsym->is_undefined()
7725 || gsym->is_preemptible())
7726 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
7727 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
7730 if (got->add_global(gsym, GOT_TYPE_STANDARD))
7731 rel_dyn->add_global_relative(
7732 gsym, elfcpp::R_ARM_RELATIVE, got,
7733 gsym->got_offset(GOT_TYPE_STANDARD));
7739 case elfcpp::R_ARM_TARGET1:
7740 case elfcpp::R_ARM_TARGET2:
7741 // These should have been mapped to other types already.
7743 case elfcpp::R_ARM_COPY:
7744 case elfcpp::R_ARM_GLOB_DAT:
7745 case elfcpp::R_ARM_JUMP_SLOT:
7746 case elfcpp::R_ARM_RELATIVE:
7747 // These are relocations which should only be seen by the
7748 // dynamic linker, and should never be seen here.
7749 gold_error(_("%s: unexpected reloc %u in object file"),
7750 object->name().c_str(), r_type);
7753 // These are initial tls relocs, which are expected when
7755 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7756 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7757 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7758 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7759 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7761 const bool is_final = gsym->final_value_is_known();
7762 const tls::Tls_optimization optimized_type
7763 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
7766 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7767 if (optimized_type == tls::TLSOPT_NONE)
7769 // Create a pair of GOT entries for the module index and
7770 // dtv-relative offset.
7771 Arm_output_data_got<big_endian>* got
7772 = target->got_section(symtab, layout);
7773 if (!parameters->doing_static_link())
7774 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
7775 target->rel_dyn_section(layout),
7776 elfcpp::R_ARM_TLS_DTPMOD32,
7777 elfcpp::R_ARM_TLS_DTPOFF32);
7779 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
7782 // FIXME: TLS optimization not supported yet.
7786 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7787 if (optimized_type == tls::TLSOPT_NONE)
7789 // Create a GOT entry for the module index.
7790 target->got_mod_index_entry(symtab, layout, object);
7793 // FIXME: TLS optimization not supported yet.
7797 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7800 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7801 layout->set_has_static_tls();
7802 if (optimized_type == tls::TLSOPT_NONE)
7804 // Create a GOT entry for the tp-relative offset.
7805 Arm_output_data_got<big_endian>* got
7806 = target->got_section(symtab, layout);
7807 if (!parameters->doing_static_link())
7808 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
7809 target->rel_dyn_section(layout),
7810 elfcpp::R_ARM_TLS_TPOFF32);
7811 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
7813 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
7814 unsigned int got_offset =
7815 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
7816 got->add_static_reloc(got_offset,
7817 elfcpp::R_ARM_TLS_TPOFF32, gsym);
7821 // FIXME: TLS optimization not supported yet.
7825 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7826 layout->set_has_static_tls();
7827 if (parameters->options().shared())
7829 // We need to create a dynamic relocation.
7830 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7831 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
7832 output_section, object,
7833 data_shndx, reloc.get_r_offset());
7844 unsupported_reloc_global(object, r_type, gsym);
7849 // Process relocations for gc.
7851 template<bool big_endian>
7853 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
7855 Sized_relobj<32, big_endian>* object,
7856 unsigned int data_shndx,
7858 const unsigned char* prelocs,
7860 Output_section* output_section,
7861 bool needs_special_offset_handling,
7862 size_t local_symbol_count,
7863 const unsigned char* plocal_symbols)
7865 typedef Target_arm<big_endian> Arm;
7866 typedef typename Target_arm<big_endian>::Scan Scan;
7868 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
7877 needs_special_offset_handling,
7882 // Scan relocations for a section.
7884 template<bool big_endian>
7886 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
7888 Sized_relobj<32, big_endian>* object,
7889 unsigned int data_shndx,
7890 unsigned int sh_type,
7891 const unsigned char* prelocs,
7893 Output_section* output_section,
7894 bool needs_special_offset_handling,
7895 size_t local_symbol_count,
7896 const unsigned char* plocal_symbols)
7898 typedef typename Target_arm<big_endian>::Scan Scan;
7899 if (sh_type == elfcpp::SHT_RELA)
7901 gold_error(_("%s: unsupported RELA reloc section"),
7902 object->name().c_str());
7906 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
7915 needs_special_offset_handling,
7920 // Finalize the sections.
7922 template<bool big_endian>
7924 Target_arm<big_endian>::do_finalize_sections(
7926 const Input_objects* input_objects,
7927 Symbol_table* symtab)
7929 // Create an empty uninitialized attribute section if we still don't have it
7931 if (this->attributes_section_data_ == NULL)
7932 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
7934 // Merge processor-specific flags.
7935 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
7936 p != input_objects->relobj_end();
7939 // If this input file is a binary file, it has no processor
7940 // specific flags and attributes section.
7941 Input_file::Format format = (*p)->input_file()->format();
7942 if (format != Input_file::FORMAT_ELF)
7944 gold_assert(format == Input_file::FORMAT_BINARY);
7948 Arm_relobj<big_endian>* arm_relobj =
7949 Arm_relobj<big_endian>::as_arm_relobj(*p);
7950 this->merge_processor_specific_flags(
7952 arm_relobj->processor_specific_flags());
7953 this->merge_object_attributes(arm_relobj->name().c_str(),
7954 arm_relobj->attributes_section_data());
7958 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
7959 p != input_objects->dynobj_end();
7962 Arm_dynobj<big_endian>* arm_dynobj =
7963 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
7964 this->merge_processor_specific_flags(
7966 arm_dynobj->processor_specific_flags());
7967 this->merge_object_attributes(arm_dynobj->name().c_str(),
7968 arm_dynobj->attributes_section_data());
7972 const Object_attribute* cpu_arch_attr =
7973 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
7974 if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
7975 this->set_may_use_blx(true);
7977 // Check if we need to use Cortex-A8 workaround.
7978 if (parameters->options().user_set_fix_cortex_a8())
7979 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
7982 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
7983 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
7985 const Object_attribute* cpu_arch_profile_attr =
7986 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
7987 this->fix_cortex_a8_ =
7988 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
7989 && (cpu_arch_profile_attr->int_value() == 'A'
7990 || cpu_arch_profile_attr->int_value() == 0));
7993 // Check if we can use V4BX interworking.
7994 // The V4BX interworking stub contains BX instruction,
7995 // which is not specified for some profiles.
7996 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
7997 && !this->may_use_blx())
7998 gold_error(_("unable to provide V4BX reloc interworking fix up; "
7999 "the target profile does not support BX instruction"));
8001 // Fill in some more dynamic tags.
8002 const Reloc_section* rel_plt = (this->plt_ == NULL
8004 : this->plt_->rel_plt());
8005 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
8006 this->rel_dyn_, true, false);
8008 // Emit any relocs we saved in an attempt to avoid generating COPY
8010 if (this->copy_relocs_.any_saved_relocs())
8011 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8013 // Handle the .ARM.exidx section.
8014 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8015 if (exidx_section != NULL
8016 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
8017 && !parameters->options().relocatable())
8019 // Create __exidx_start and __exdix_end symbols.
8020 symtab->define_in_output_data("__exidx_start", NULL,
8021 Symbol_table::PREDEFINED,
8022 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8023 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8025 symtab->define_in_output_data("__exidx_end", NULL,
8026 Symbol_table::PREDEFINED,
8027 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8028 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8031 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8032 // the .ARM.exidx section.
8033 if (!layout->script_options()->saw_phdrs_clause())
8035 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
8037 Output_segment* exidx_segment =
8038 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8039 exidx_segment->add_output_section(exidx_section, elfcpp::PF_R,
8044 // Create an .ARM.attributes section if there is not one already.
8045 Output_attributes_section_data* attributes_section =
8046 new Output_attributes_section_data(*this->attributes_section_data_);
8047 layout->add_output_section_data(".ARM.attributes",
8048 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8049 attributes_section, false, false, false,
8053 // Return whether a direct absolute static relocation needs to be applied.
8054 // In cases where Scan::local() or Scan::global() has created
8055 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8056 // of the relocation is carried in the data, and we must not
8057 // apply the static relocation.
8059 template<bool big_endian>
8061 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8062 const Sized_symbol<32>* gsym,
8065 Output_section* output_section)
8067 // If the output section is not allocated, then we didn't call
8068 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8070 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8073 // For local symbols, we will have created a non-RELATIVE dynamic
8074 // relocation only if (a) the output is position independent,
8075 // (b) the relocation is absolute (not pc- or segment-relative), and
8076 // (c) the relocation is not 32 bits wide.
8078 return !(parameters->options().output_is_position_independent()
8079 && (ref_flags & Symbol::ABSOLUTE_REF)
8082 // For global symbols, we use the same helper routines used in the
8083 // scan pass. If we did not create a dynamic relocation, or if we
8084 // created a RELATIVE dynamic relocation, we should apply the static
8086 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8087 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8088 && gsym->can_use_relative_reloc(ref_flags
8089 & Symbol::FUNCTION_CALL);
8090 return !has_dyn || is_rel;
8093 // Perform a relocation.
8095 template<bool big_endian>
8097 Target_arm<big_endian>::Relocate::relocate(
8098 const Relocate_info<32, big_endian>* relinfo,
8100 Output_section *output_section,
8102 const elfcpp::Rel<32, big_endian>& rel,
8103 unsigned int r_type,
8104 const Sized_symbol<32>* gsym,
8105 const Symbol_value<32>* psymval,
8106 unsigned char* view,
8107 Arm_address address,
8108 section_size_type view_size)
8110 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8112 r_type = get_real_reloc_type(r_type);
8113 const Arm_reloc_property* reloc_property =
8114 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8115 if (reloc_property == NULL)
8117 std::string reloc_name =
8118 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8119 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8120 _("cannot relocate %s in object file"),
8121 reloc_name.c_str());
8125 const Arm_relobj<big_endian>* object =
8126 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8128 // If the final branch target of a relocation is THUMB instruction, this
8129 // is 1. Otherwise it is 0.
8130 Arm_address thumb_bit = 0;
8131 Symbol_value<32> symval;
8132 bool is_weakly_undefined_without_plt = false;
8133 if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8137 // This is a global symbol. Determine if we use PLT and if the
8138 // final target is THUMB.
8139 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
8141 // This uses a PLT, change the symbol value.
8142 symval.set_output_value(target->plt_section()->address()
8143 + gsym->plt_offset());
8146 else if (gsym->is_weak_undefined())
8148 // This is a weakly undefined symbol and we do not use PLT
8149 // for this relocation. A branch targeting this symbol will
8150 // be converted into an NOP.
8151 is_weakly_undefined_without_plt = true;
8155 // Set thumb bit if symbol:
8156 // -Has type STT_ARM_TFUNC or
8157 // -Has type STT_FUNC, is defined and with LSB in value set.
8159 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8160 || (gsym->type() == elfcpp::STT_FUNC
8161 && !gsym->is_undefined()
8162 && ((psymval->value(object, 0) & 1) != 0)))
8169 // This is a local symbol. Determine if the final target is THUMB.
8170 // We saved this information when all the local symbols were read.
8171 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8172 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8173 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8178 // This is a fake relocation synthesized for a stub. It does not have
8179 // a real symbol. We just look at the LSB of the symbol value to
8180 // determine if the target is THUMB or not.
8181 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8184 // Strip LSB if this points to a THUMB target.
8186 && reloc_property->uses_thumb_bit()
8187 && ((psymval->value(object, 0) & 1) != 0))
8189 Arm_address stripped_value =
8190 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8191 symval.set_output_value(stripped_value);
8195 // Get the GOT offset if needed.
8196 // The GOT pointer points to the end of the GOT section.
8197 // We need to subtract the size of the GOT section to get
8198 // the actual offset to use in the relocation.
8199 bool have_got_offset = false;
8200 unsigned int got_offset = 0;
8203 case elfcpp::R_ARM_GOT_BREL:
8204 case elfcpp::R_ARM_GOT_PREL:
8207 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8208 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8209 - target->got_size());
8213 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8214 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
8215 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8216 - target->got_size());
8218 have_got_offset = true;
8225 // To look up relocation stubs, we need to pass the symbol table index of
8227 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8229 // Get the addressing origin of the output segment defining the
8230 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8231 Arm_address sym_origin = 0;
8232 if (reloc_property->uses_symbol_base())
8234 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8235 // R_ARM_BASE_ABS with the NULL symbol will give the
8236 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8237 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8238 sym_origin = target->got_plt_section()->address();
8239 else if (gsym == NULL)
8241 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8242 sym_origin = gsym->output_segment()->vaddr();
8243 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8244 sym_origin = gsym->output_data()->address();
8246 // TODO: Assumes the segment base to be zero for the global symbols
8247 // till the proper support for the segment-base-relative addressing
8248 // will be implemented. This is consistent with GNU ld.
8251 // For relative addressing relocation, find out the relative address base.
8252 Arm_address relative_address_base = 0;
8253 switch(reloc_property->relative_address_base())
8255 case Arm_reloc_property::RAB_NONE:
8256 // Relocations with relative address bases RAB_TLS and RAB_tp are
8257 // handled by relocate_tls. So we do not need to do anything here.
8258 case Arm_reloc_property::RAB_TLS:
8259 case Arm_reloc_property::RAB_tp:
8261 case Arm_reloc_property::RAB_B_S:
8262 relative_address_base = sym_origin;
8264 case Arm_reloc_property::RAB_GOT_ORG:
8265 relative_address_base = target->got_plt_section()->address();
8267 case Arm_reloc_property::RAB_P:
8268 relative_address_base = address;
8270 case Arm_reloc_property::RAB_Pa:
8271 relative_address_base = address & 0xfffffffcU;
8277 typename Arm_relocate_functions::Status reloc_status =
8278 Arm_relocate_functions::STATUS_OKAY;
8279 bool check_overflow = reloc_property->checks_overflow();
8282 case elfcpp::R_ARM_NONE:
8285 case elfcpp::R_ARM_ABS8:
8286 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8288 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
8291 case elfcpp::R_ARM_ABS12:
8292 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8294 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
8297 case elfcpp::R_ARM_ABS16:
8298 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8300 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
8303 case elfcpp::R_ARM_ABS32:
8304 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8306 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8310 case elfcpp::R_ARM_ABS32_NOI:
8311 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8313 // No thumb bit for this relocation: (S + A)
8314 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8318 case elfcpp::R_ARM_MOVW_ABS_NC:
8319 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8321 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
8326 case elfcpp::R_ARM_MOVT_ABS:
8327 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8329 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
8332 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8333 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8335 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
8336 0, thumb_bit, false);
8339 case elfcpp::R_ARM_THM_MOVT_ABS:
8340 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8342 reloc_status = Arm_relocate_functions::thm_movt(view, object,
8346 case elfcpp::R_ARM_MOVW_PREL_NC:
8347 case elfcpp::R_ARM_MOVW_BREL_NC:
8348 case elfcpp::R_ARM_MOVW_BREL:
8350 Arm_relocate_functions::movw(view, object, psymval,
8351 relative_address_base, thumb_bit,
8355 case elfcpp::R_ARM_MOVT_PREL:
8356 case elfcpp::R_ARM_MOVT_BREL:
8358 Arm_relocate_functions::movt(view, object, psymval,
8359 relative_address_base);
8362 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8363 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8364 case elfcpp::R_ARM_THM_MOVW_BREL:
8366 Arm_relocate_functions::thm_movw(view, object, psymval,
8367 relative_address_base,
8368 thumb_bit, check_overflow);
8371 case elfcpp::R_ARM_THM_MOVT_PREL:
8372 case elfcpp::R_ARM_THM_MOVT_BREL:
8374 Arm_relocate_functions::thm_movt(view, object, psymval,
8375 relative_address_base);
8378 case elfcpp::R_ARM_REL32:
8379 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8380 address, thumb_bit);
8383 case elfcpp::R_ARM_THM_ABS5:
8384 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8386 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
8389 // Thumb long branches.
8390 case elfcpp::R_ARM_THM_CALL:
8391 case elfcpp::R_ARM_THM_XPC22:
8392 case elfcpp::R_ARM_THM_JUMP24:
8394 Arm_relocate_functions::thumb_branch_common(
8395 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8396 thumb_bit, is_weakly_undefined_without_plt);
8399 case elfcpp::R_ARM_GOTOFF32:
8401 Arm_address got_origin;
8402 got_origin = target->got_plt_section()->address();
8403 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8404 got_origin, thumb_bit);
8408 case elfcpp::R_ARM_BASE_PREL:
8409 gold_assert(gsym != NULL);
8411 Arm_relocate_functions::base_prel(view, sym_origin, address);
8414 case elfcpp::R_ARM_BASE_ABS:
8416 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8420 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
8424 case elfcpp::R_ARM_GOT_BREL:
8425 gold_assert(have_got_offset);
8426 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
8429 case elfcpp::R_ARM_GOT_PREL:
8430 gold_assert(have_got_offset);
8431 // Get the address origin for GOT PLT, which is allocated right
8432 // after the GOT section, to calculate an absolute address of
8433 // the symbol GOT entry (got_origin + got_offset).
8434 Arm_address got_origin;
8435 got_origin = target->got_plt_section()->address();
8436 reloc_status = Arm_relocate_functions::got_prel(view,
8437 got_origin + got_offset,
8441 case elfcpp::R_ARM_PLT32:
8442 case elfcpp::R_ARM_CALL:
8443 case elfcpp::R_ARM_JUMP24:
8444 case elfcpp::R_ARM_XPC25:
8445 gold_assert(gsym == NULL
8446 || gsym->has_plt_offset()
8447 || gsym->final_value_is_known()
8448 || (gsym->is_defined()
8449 && !gsym->is_from_dynobj()
8450 && !gsym->is_preemptible()));
8452 Arm_relocate_functions::arm_branch_common(
8453 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8454 thumb_bit, is_weakly_undefined_without_plt);
8457 case elfcpp::R_ARM_THM_JUMP19:
8459 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
8463 case elfcpp::R_ARM_THM_JUMP6:
8465 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
8468 case elfcpp::R_ARM_THM_JUMP8:
8470 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
8473 case elfcpp::R_ARM_THM_JUMP11:
8475 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
8478 case elfcpp::R_ARM_PREL31:
8479 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
8480 address, thumb_bit);
8483 case elfcpp::R_ARM_V4BX:
8484 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
8486 const bool is_v4bx_interworking =
8487 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
8489 Arm_relocate_functions::v4bx(relinfo, view, object, address,
8490 is_v4bx_interworking);
8494 case elfcpp::R_ARM_THM_PC8:
8496 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
8499 case elfcpp::R_ARM_THM_PC12:
8501 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
8504 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8506 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
8510 case elfcpp::R_ARM_ALU_PC_G0_NC:
8511 case elfcpp::R_ARM_ALU_PC_G0:
8512 case elfcpp::R_ARM_ALU_PC_G1_NC:
8513 case elfcpp::R_ARM_ALU_PC_G1:
8514 case elfcpp::R_ARM_ALU_PC_G2:
8515 case elfcpp::R_ARM_ALU_SB_G0_NC:
8516 case elfcpp::R_ARM_ALU_SB_G0:
8517 case elfcpp::R_ARM_ALU_SB_G1_NC:
8518 case elfcpp::R_ARM_ALU_SB_G1:
8519 case elfcpp::R_ARM_ALU_SB_G2:
8521 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
8522 reloc_property->group_index(),
8523 relative_address_base,
8524 thumb_bit, check_overflow);
8527 case elfcpp::R_ARM_LDR_PC_G0:
8528 case elfcpp::R_ARM_LDR_PC_G1:
8529 case elfcpp::R_ARM_LDR_PC_G2:
8530 case elfcpp::R_ARM_LDR_SB_G0:
8531 case elfcpp::R_ARM_LDR_SB_G1:
8532 case elfcpp::R_ARM_LDR_SB_G2:
8534 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
8535 reloc_property->group_index(),
8536 relative_address_base);
8539 case elfcpp::R_ARM_LDRS_PC_G0:
8540 case elfcpp::R_ARM_LDRS_PC_G1:
8541 case elfcpp::R_ARM_LDRS_PC_G2:
8542 case elfcpp::R_ARM_LDRS_SB_G0:
8543 case elfcpp::R_ARM_LDRS_SB_G1:
8544 case elfcpp::R_ARM_LDRS_SB_G2:
8546 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
8547 reloc_property->group_index(),
8548 relative_address_base);
8551 case elfcpp::R_ARM_LDC_PC_G0:
8552 case elfcpp::R_ARM_LDC_PC_G1:
8553 case elfcpp::R_ARM_LDC_PC_G2:
8554 case elfcpp::R_ARM_LDC_SB_G0:
8555 case elfcpp::R_ARM_LDC_SB_G1:
8556 case elfcpp::R_ARM_LDC_SB_G2:
8558 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
8559 reloc_property->group_index(),
8560 relative_address_base);
8563 // These are initial tls relocs, which are expected when
8565 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8566 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8567 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8568 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8569 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8571 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
8572 view, address, view_size);
8579 // Report any errors.
8580 switch (reloc_status)
8582 case Arm_relocate_functions::STATUS_OKAY:
8584 case Arm_relocate_functions::STATUS_OVERFLOW:
8585 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8586 _("relocation overflow in %s"),
8587 reloc_property->name().c_str());
8589 case Arm_relocate_functions::STATUS_BAD_RELOC:
8590 gold_error_at_location(
8594 _("unexpected opcode while processing relocation %s"),
8595 reloc_property->name().c_str());
8604 // Perform a TLS relocation.
8606 template<bool big_endian>
8607 inline typename Arm_relocate_functions<big_endian>::Status
8608 Target_arm<big_endian>::Relocate::relocate_tls(
8609 const Relocate_info<32, big_endian>* relinfo,
8610 Target_arm<big_endian>* target,
8612 const elfcpp::Rel<32, big_endian>& rel,
8613 unsigned int r_type,
8614 const Sized_symbol<32>* gsym,
8615 const Symbol_value<32>* psymval,
8616 unsigned char* view,
8617 elfcpp::Elf_types<32>::Elf_Addr address,
8618 section_size_type /*view_size*/ )
8620 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
8621 typedef Relocate_functions<32, big_endian> RelocFuncs;
8622 Output_segment* tls_segment = relinfo->layout->tls_segment();
8624 const Sized_relobj<32, big_endian>* object = relinfo->object;
8626 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
8628 const bool is_final = (gsym == NULL
8629 ? !parameters->options().shared()
8630 : gsym->final_value_is_known());
8631 const tls::Tls_optimization optimized_type
8632 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8635 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8637 unsigned int got_type = GOT_TYPE_TLS_PAIR;
8638 unsigned int got_offset;
8641 gold_assert(gsym->has_got_offset(got_type));
8642 got_offset = gsym->got_offset(got_type) - target->got_size();
8646 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8647 gold_assert(object->local_has_got_offset(r_sym, got_type));
8648 got_offset = (object->local_got_offset(r_sym, got_type)
8649 - target->got_size());
8651 if (optimized_type == tls::TLSOPT_NONE)
8653 Arm_address got_entry =
8654 target->got_plt_section()->address() + got_offset;
8656 // Relocate the field with the PC relative offset of the pair of
8658 RelocFuncs::pcrel32(view, got_entry, address);
8659 return ArmRelocFuncs::STATUS_OKAY;
8664 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8665 if (optimized_type == tls::TLSOPT_NONE)
8667 // Relocate the field with the offset of the GOT entry for
8668 // the module index.
8669 unsigned int got_offset;
8670 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
8671 - target->got_size());
8672 Arm_address got_entry =
8673 target->got_plt_section()->address() + got_offset;
8675 // Relocate the field with the PC relative offset of the pair of
8677 RelocFuncs::pcrel32(view, got_entry, address);
8678 return ArmRelocFuncs::STATUS_OKAY;
8682 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8683 RelocFuncs::rel32(view, value);
8684 return ArmRelocFuncs::STATUS_OKAY;
8686 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8687 if (optimized_type == tls::TLSOPT_NONE)
8689 // Relocate the field with the offset of the GOT entry for
8690 // the tp-relative offset of the symbol.
8691 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
8692 unsigned int got_offset;
8695 gold_assert(gsym->has_got_offset(got_type));
8696 got_offset = gsym->got_offset(got_type);
8700 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8701 gold_assert(object->local_has_got_offset(r_sym, got_type));
8702 got_offset = object->local_got_offset(r_sym, got_type);
8705 // All GOT offsets are relative to the end of the GOT.
8706 got_offset -= target->got_size();
8708 Arm_address got_entry =
8709 target->got_plt_section()->address() + got_offset;
8711 // Relocate the field with the PC relative offset of the GOT entry.
8712 RelocFuncs::pcrel32(view, got_entry, address);
8713 return ArmRelocFuncs::STATUS_OKAY;
8717 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8718 // If we're creating a shared library, a dynamic relocation will
8719 // have been created for this location, so do not apply it now.
8720 if (!parameters->options().shared())
8722 gold_assert(tls_segment != NULL);
8724 // $tp points to the TCB, which is followed by the TLS, so we
8725 // need to add TCB size to the offset.
8726 Arm_address aligned_tcb_size =
8727 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
8728 RelocFuncs::rel32(view, value + aligned_tcb_size);
8731 return ArmRelocFuncs::STATUS_OKAY;
8737 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8738 _("unsupported reloc %u"),
8740 return ArmRelocFuncs::STATUS_BAD_RELOC;
8743 // Relocate section data.
8745 template<bool big_endian>
8747 Target_arm<big_endian>::relocate_section(
8748 const Relocate_info<32, big_endian>* relinfo,
8749 unsigned int sh_type,
8750 const unsigned char* prelocs,
8752 Output_section* output_section,
8753 bool needs_special_offset_handling,
8754 unsigned char* view,
8755 Arm_address address,
8756 section_size_type view_size,
8757 const Reloc_symbol_changes* reloc_symbol_changes)
8759 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
8760 gold_assert(sh_type == elfcpp::SHT_REL);
8762 // See if we are relocating a relaxed input section. If so, the view
8763 // covers the whole output section and we need to adjust accordingly.
8764 if (needs_special_offset_handling)
8766 const Output_relaxed_input_section* poris =
8767 output_section->find_relaxed_input_section(relinfo->object,
8768 relinfo->data_shndx);
8771 Arm_address section_address = poris->address();
8772 section_size_type section_size = poris->data_size();
8774 gold_assert((section_address >= address)
8775 && ((section_address + section_size)
8776 <= (address + view_size)));
8778 off_t offset = section_address - address;
8781 view_size = section_size;
8785 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
8792 needs_special_offset_handling,
8796 reloc_symbol_changes);
8799 // Return the size of a relocation while scanning during a relocatable
8802 template<bool big_endian>
8804 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
8805 unsigned int r_type,
8808 r_type = get_real_reloc_type(r_type);
8809 const Arm_reloc_property* arp =
8810 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8815 std::string reloc_name =
8816 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8817 gold_error(_("%s: unexpected %s in object file"),
8818 object->name().c_str(), reloc_name.c_str());
8823 // Scan the relocs during a relocatable link.
8825 template<bool big_endian>
8827 Target_arm<big_endian>::scan_relocatable_relocs(
8828 Symbol_table* symtab,
8830 Sized_relobj<32, big_endian>* object,
8831 unsigned int data_shndx,
8832 unsigned int sh_type,
8833 const unsigned char* prelocs,
8835 Output_section* output_section,
8836 bool needs_special_offset_handling,
8837 size_t local_symbol_count,
8838 const unsigned char* plocal_symbols,
8839 Relocatable_relocs* rr)
8841 gold_assert(sh_type == elfcpp::SHT_REL);
8843 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
8844 Relocatable_size_for_reloc> Scan_relocatable_relocs;
8846 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
8847 Scan_relocatable_relocs>(
8855 needs_special_offset_handling,
8861 // Relocate a section during a relocatable link.
8863 template<bool big_endian>
8865 Target_arm<big_endian>::relocate_for_relocatable(
8866 const Relocate_info<32, big_endian>* relinfo,
8867 unsigned int sh_type,
8868 const unsigned char* prelocs,
8870 Output_section* output_section,
8871 off_t offset_in_output_section,
8872 const Relocatable_relocs* rr,
8873 unsigned char* view,
8874 Arm_address view_address,
8875 section_size_type view_size,
8876 unsigned char* reloc_view,
8877 section_size_type reloc_view_size)
8879 gold_assert(sh_type == elfcpp::SHT_REL);
8881 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
8886 offset_in_output_section,
8895 // Return the value to use for a dynamic symbol which requires special
8896 // treatment. This is how we support equality comparisons of function
8897 // pointers across shared library boundaries, as described in the
8898 // processor specific ABI supplement.
8900 template<bool big_endian>
8902 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
8904 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
8905 return this->plt_section()->address() + gsym->plt_offset();
8908 // Map platform-specific relocs to real relocs
8910 template<bool big_endian>
8912 Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
8916 case elfcpp::R_ARM_TARGET1:
8917 // This is either R_ARM_ABS32 or R_ARM_REL32;
8918 return elfcpp::R_ARM_ABS32;
8920 case elfcpp::R_ARM_TARGET2:
8921 // This can be any reloc type but ususally is R_ARM_GOT_PREL
8922 return elfcpp::R_ARM_GOT_PREL;
8929 // Whether if two EABI versions V1 and V2 are compatible.
8931 template<bool big_endian>
8933 Target_arm<big_endian>::are_eabi_versions_compatible(
8934 elfcpp::Elf_Word v1,
8935 elfcpp::Elf_Word v2)
8937 // v4 and v5 are the same spec before and after it was released,
8938 // so allow mixing them.
8939 if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
8940 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
8946 // Combine FLAGS from an input object called NAME and the processor-specific
8947 // flags in the ELF header of the output. Much of this is adapted from the
8948 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
8949 // in bfd/elf32-arm.c.
8951 template<bool big_endian>
8953 Target_arm<big_endian>::merge_processor_specific_flags(
8954 const std::string& name,
8955 elfcpp::Elf_Word flags)
8957 if (this->are_processor_specific_flags_set())
8959 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
8961 // Nothing to merge if flags equal to those in output.
8962 if (flags == out_flags)
8965 // Complain about various flag mismatches.
8966 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
8967 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
8968 if (!this->are_eabi_versions_compatible(version1, version2))
8969 gold_error(_("Source object %s has EABI version %d but output has "
8970 "EABI version %d."),
8972 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
8973 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
8977 // If the input is the default architecture and had the default
8978 // flags then do not bother setting the flags for the output
8979 // architecture, instead allow future merges to do this. If no
8980 // future merges ever set these flags then they will retain their
8981 // uninitialised values, which surprise surprise, correspond
8982 // to the default values.
8986 // This is the first time, just copy the flags.
8987 // We only copy the EABI version for now.
8988 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
8992 // Adjust ELF file header.
8993 template<bool big_endian>
8995 Target_arm<big_endian>::do_adjust_elf_header(
8996 unsigned char* view,
8999 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
9001 elfcpp::Ehdr<32, big_endian> ehdr(view);
9002 unsigned char e_ident[elfcpp::EI_NIDENT];
9003 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
9005 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
9006 == elfcpp::EF_ARM_EABI_UNKNOWN)
9007 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
9009 e_ident[elfcpp::EI_OSABI] = 0;
9010 e_ident[elfcpp::EI_ABIVERSION] = 0;
9012 // FIXME: Do EF_ARM_BE8 adjustment.
9014 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
9015 oehdr.put_e_ident(e_ident);
9018 // do_make_elf_object to override the same function in the base class.
9019 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
9020 // to store ARM specific information. Hence we need to have our own
9021 // ELF object creation.
9023 template<bool big_endian>
9025 Target_arm<big_endian>::do_make_elf_object(
9026 const std::string& name,
9027 Input_file* input_file,
9028 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
9030 int et = ehdr.get_e_type();
9031 if (et == elfcpp::ET_REL)
9033 Arm_relobj<big_endian>* obj =
9034 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
9038 else if (et == elfcpp::ET_DYN)
9040 Sized_dynobj<32, big_endian>* obj =
9041 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
9047 gold_error(_("%s: unsupported ELF file type %d"),
9053 // Read the architecture from the Tag_also_compatible_with attribute, if any.
9054 // Returns -1 if no architecture could be read.
9055 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
9057 template<bool big_endian>
9059 Target_arm<big_endian>::get_secondary_compatible_arch(
9060 const Attributes_section_data* pasd)
9062 const Object_attribute *known_attributes =
9063 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9065 // Note: the tag and its argument below are uleb128 values, though
9066 // currently-defined values fit in one byte for each.
9067 const std::string& sv =
9068 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
9070 && sv.data()[0] == elfcpp::Tag_CPU_arch
9071 && (sv.data()[1] & 128) != 128)
9072 return sv.data()[1];
9074 // This tag is "safely ignorable", so don't complain if it looks funny.
9078 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
9079 // The tag is removed if ARCH is -1.
9080 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
9082 template<bool big_endian>
9084 Target_arm<big_endian>::set_secondary_compatible_arch(
9085 Attributes_section_data* pasd,
9088 Object_attribute *known_attributes =
9089 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9093 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
9097 // Note: the tag and its argument below are uleb128 values, though
9098 // currently-defined values fit in one byte for each.
9100 sv[0] = elfcpp::Tag_CPU_arch;
9101 gold_assert(arch != 0);
9105 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
9108 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
9110 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
9112 template<bool big_endian>
9114 Target_arm<big_endian>::tag_cpu_arch_combine(
9117 int* secondary_compat_out,
9119 int secondary_compat)
9121 #define T(X) elfcpp::TAG_CPU_ARCH_##X
9122 static const int v6t2[] =
9134 static const int v6k[] =
9147 static const int v7[] =
9161 static const int v6_m[] =
9176 static const int v6s_m[] =
9192 static const int v7e_m[] =
9209 static const int v4t_plus_v6_m[] =
9225 T(V4T_PLUS_V6_M) // V4T plus V6_M.
9227 static const int *comb[] =
9235 // Pseudo-architecture.
9239 // Check we've not got a higher architecture than we know about.
9241 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
9243 gold_error(_("%s: unknown CPU architecture"), name);
9247 // Override old tag if we have a Tag_also_compatible_with on the output.
9249 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
9250 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
9251 oldtag = T(V4T_PLUS_V6_M);
9253 // And override the new tag if we have a Tag_also_compatible_with on the
9256 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
9257 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
9258 newtag = T(V4T_PLUS_V6_M);
9260 // Architectures before V6KZ add features monotonically.
9261 int tagh = std::max(oldtag, newtag);
9262 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
9265 int tagl = std::min(oldtag, newtag);
9266 int result = comb[tagh - T(V6T2)][tagl];
9268 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
9269 // as the canonical version.
9270 if (result == T(V4T_PLUS_V6_M))
9273 *secondary_compat_out = T(V6_M);
9276 *secondary_compat_out = -1;
9280 gold_error(_("%s: conflicting CPU architectures %d/%d"),
9281 name, oldtag, newtag);
9289 // Helper to print AEABI enum tag value.
9291 template<bool big_endian>
9293 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
9295 static const char *aeabi_enum_names[] =
9296 { "", "variable-size", "32-bit", "" };
9297 const size_t aeabi_enum_names_size =
9298 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
9300 if (value < aeabi_enum_names_size)
9301 return std::string(aeabi_enum_names[value]);
9305 sprintf(buffer, "<unknown value %u>", value);
9306 return std::string(buffer);
9310 // Return the string value to store in TAG_CPU_name.
9312 template<bool big_endian>
9314 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
9316 static const char *name_table[] = {
9317 // These aren't real CPU names, but we can't guess
9318 // that from the architecture version alone.
9334 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
9336 if (value < name_table_size)
9337 return std::string(name_table[value]);
9341 sprintf(buffer, "<unknown CPU value %u>", value);
9342 return std::string(buffer);
9346 // Merge object attributes from input file called NAME with those of the
9347 // output. The input object attributes are in the object pointed by PASD.
9349 template<bool big_endian>
9351 Target_arm<big_endian>::merge_object_attributes(
9353 const Attributes_section_data* pasd)
9355 // Return if there is no attributes section data.
9359 // If output has no object attributes, just copy.
9360 if (this->attributes_section_data_ == NULL)
9362 this->attributes_section_data_ = new Attributes_section_data(*pasd);
9366 const int vendor = Object_attribute::OBJ_ATTR_PROC;
9367 const Object_attribute* in_attr = pasd->known_attributes(vendor);
9368 Object_attribute* out_attr =
9369 this->attributes_section_data_->known_attributes(vendor);
9371 // This needs to happen before Tag_ABI_FP_number_model is merged. */
9372 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
9373 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
9375 // Ignore mismatches if the object doesn't use floating point. */
9376 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
9377 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
9378 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
9379 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0)
9380 gold_error(_("%s uses VFP register arguments, output does not"),
9384 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
9386 // Merge this attribute with existing attributes.
9389 case elfcpp::Tag_CPU_raw_name:
9390 case elfcpp::Tag_CPU_name:
9391 // These are merged after Tag_CPU_arch.
9394 case elfcpp::Tag_ABI_optimization_goals:
9395 case elfcpp::Tag_ABI_FP_optimization_goals:
9396 // Use the first value seen.
9399 case elfcpp::Tag_CPU_arch:
9401 unsigned int saved_out_attr = out_attr->int_value();
9402 // Merge Tag_CPU_arch and Tag_also_compatible_with.
9403 int secondary_compat =
9404 this->get_secondary_compatible_arch(pasd);
9405 int secondary_compat_out =
9406 this->get_secondary_compatible_arch(
9407 this->attributes_section_data_);
9408 out_attr[i].set_int_value(
9409 tag_cpu_arch_combine(name, out_attr[i].int_value(),
9410 &secondary_compat_out,
9411 in_attr[i].int_value(),
9413 this->set_secondary_compatible_arch(this->attributes_section_data_,
9414 secondary_compat_out);
9416 // Merge Tag_CPU_name and Tag_CPU_raw_name.
9417 if (out_attr[i].int_value() == saved_out_attr)
9418 ; // Leave the names alone.
9419 else if (out_attr[i].int_value() == in_attr[i].int_value())
9421 // The output architecture has been changed to match the
9422 // input architecture. Use the input names.
9423 out_attr[elfcpp::Tag_CPU_name].set_string_value(
9424 in_attr[elfcpp::Tag_CPU_name].string_value());
9425 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
9426 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
9430 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
9431 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
9434 // If we still don't have a value for Tag_CPU_name,
9435 // make one up now. Tag_CPU_raw_name remains blank.
9436 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
9438 const std::string cpu_name =
9439 this->tag_cpu_name_value(out_attr[i].int_value());
9440 // FIXME: If we see an unknown CPU, this will be set
9441 // to "<unknown CPU n>", where n is the attribute value.
9442 // This is different from BFD, which leaves the name alone.
9443 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
9448 case elfcpp::Tag_ARM_ISA_use:
9449 case elfcpp::Tag_THUMB_ISA_use:
9450 case elfcpp::Tag_WMMX_arch:
9451 case elfcpp::Tag_Advanced_SIMD_arch:
9452 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
9453 case elfcpp::Tag_ABI_FP_rounding:
9454 case elfcpp::Tag_ABI_FP_exceptions:
9455 case elfcpp::Tag_ABI_FP_user_exceptions:
9456 case elfcpp::Tag_ABI_FP_number_model:
9457 case elfcpp::Tag_VFP_HP_extension:
9458 case elfcpp::Tag_CPU_unaligned_access:
9459 case elfcpp::Tag_T2EE_use:
9460 case elfcpp::Tag_Virtualization_use:
9461 case elfcpp::Tag_MPextension_use:
9462 // Use the largest value specified.
9463 if (in_attr[i].int_value() > out_attr[i].int_value())
9464 out_attr[i].set_int_value(in_attr[i].int_value());
9467 case elfcpp::Tag_ABI_align8_preserved:
9468 case elfcpp::Tag_ABI_PCS_RO_data:
9469 // Use the smallest value specified.
9470 if (in_attr[i].int_value() < out_attr[i].int_value())
9471 out_attr[i].set_int_value(in_attr[i].int_value());
9474 case elfcpp::Tag_ABI_align8_needed:
9475 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
9476 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
9477 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
9480 // This error message should be enabled once all non-conformant
9481 // binaries in the toolchain have had the attributes set
9483 // gold_error(_("output 8-byte data alignment conflicts with %s"),
9487 case elfcpp::Tag_ABI_FP_denormal:
9488 case elfcpp::Tag_ABI_PCS_GOT_use:
9490 // These tags have 0 = don't care, 1 = strong requirement,
9491 // 2 = weak requirement.
9492 static const int order_021[3] = {0, 2, 1};
9494 // Use the "greatest" from the sequence 0, 2, 1, or the largest
9495 // value if greater than 2 (for future-proofing).
9496 if ((in_attr[i].int_value() > 2
9497 && in_attr[i].int_value() > out_attr[i].int_value())
9498 || (in_attr[i].int_value() <= 2
9499 && out_attr[i].int_value() <= 2
9500 && (order_021[in_attr[i].int_value()]
9501 > order_021[out_attr[i].int_value()])))
9502 out_attr[i].set_int_value(in_attr[i].int_value());
9506 case elfcpp::Tag_CPU_arch_profile:
9507 if (out_attr[i].int_value() != in_attr[i].int_value())
9509 // 0 will merge with anything.
9510 // 'A' and 'S' merge to 'A'.
9511 // 'R' and 'S' merge to 'R'.
9512 // 'M' and 'A|R|S' is an error.
9513 if (out_attr[i].int_value() == 0
9514 || (out_attr[i].int_value() == 'S'
9515 && (in_attr[i].int_value() == 'A'
9516 || in_attr[i].int_value() == 'R')))
9517 out_attr[i].set_int_value(in_attr[i].int_value());
9518 else if (in_attr[i].int_value() == 0
9519 || (in_attr[i].int_value() == 'S'
9520 && (out_attr[i].int_value() == 'A'
9521 || out_attr[i].int_value() == 'R')))
9526 (_("conflicting architecture profiles %c/%c"),
9527 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
9528 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
9532 case elfcpp::Tag_VFP_arch:
9549 // Values greater than 6 aren't defined, so just pick the
9551 if (in_attr[i].int_value() > 6
9552 && in_attr[i].int_value() > out_attr[i].int_value())
9554 *out_attr = *in_attr;
9557 // The output uses the superset of input features
9558 // (ISA version) and registers.
9559 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
9560 vfp_versions[out_attr[i].int_value()].ver);
9561 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
9562 vfp_versions[out_attr[i].int_value()].regs);
9563 // This assumes all possible supersets are also a valid
9566 for (newval = 6; newval > 0; newval--)
9568 if (regs == vfp_versions[newval].regs
9569 && ver == vfp_versions[newval].ver)
9572 out_attr[i].set_int_value(newval);
9575 case elfcpp::Tag_PCS_config:
9576 if (out_attr[i].int_value() == 0)
9577 out_attr[i].set_int_value(in_attr[i].int_value());
9578 else if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9580 // It's sometimes ok to mix different configs, so this is only
9582 gold_warning(_("%s: conflicting platform configuration"), name);
9585 case elfcpp::Tag_ABI_PCS_R9_use:
9586 if (in_attr[i].int_value() != out_attr[i].int_value()
9587 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
9588 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused)
9590 gold_error(_("%s: conflicting use of R9"), name);
9592 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
9593 out_attr[i].set_int_value(in_attr[i].int_value());
9595 case elfcpp::Tag_ABI_PCS_RW_data:
9596 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
9597 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9598 != elfcpp::AEABI_R9_SB)
9599 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9600 != elfcpp::AEABI_R9_unused))
9602 gold_error(_("%s: SB relative addressing conflicts with use "
9606 // Use the smallest value specified.
9607 if (in_attr[i].int_value() < out_attr[i].int_value())
9608 out_attr[i].set_int_value(in_attr[i].int_value());
9610 case elfcpp::Tag_ABI_PCS_wchar_t:
9611 // FIXME: Make it possible to turn off this warning.
9612 if (out_attr[i].int_value()
9613 && in_attr[i].int_value()
9614 && out_attr[i].int_value() != in_attr[i].int_value())
9616 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
9617 "use %u-byte wchar_t; use of wchar_t values "
9618 "across objects may fail"),
9619 name, in_attr[i].int_value(),
9620 out_attr[i].int_value());
9622 else if (in_attr[i].int_value() && !out_attr[i].int_value())
9623 out_attr[i].set_int_value(in_attr[i].int_value());
9625 case elfcpp::Tag_ABI_enum_size:
9626 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
9628 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
9629 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
9631 // The existing object is compatible with anything.
9632 // Use whatever requirements the new object has.
9633 out_attr[i].set_int_value(in_attr[i].int_value());
9635 // FIXME: Make it possible to turn off this warning.
9636 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
9637 && out_attr[i].int_value() != in_attr[i].int_value())
9639 unsigned int in_value = in_attr[i].int_value();
9640 unsigned int out_value = out_attr[i].int_value();
9641 gold_warning(_("%s uses %s enums yet the output is to use "
9642 "%s enums; use of enum values across objects "
9645 this->aeabi_enum_name(in_value).c_str(),
9646 this->aeabi_enum_name(out_value).c_str());
9650 case elfcpp::Tag_ABI_VFP_args:
9653 case elfcpp::Tag_ABI_WMMX_args:
9654 if (in_attr[i].int_value() != out_attr[i].int_value())
9656 gold_error(_("%s uses iWMMXt register arguments, output does "
9661 case Object_attribute::Tag_compatibility:
9662 // Merged in target-independent code.
9664 case elfcpp::Tag_ABI_HardFP_use:
9665 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
9666 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
9667 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
9668 out_attr[i].set_int_value(3);
9669 else if (in_attr[i].int_value() > out_attr[i].int_value())
9670 out_attr[i].set_int_value(in_attr[i].int_value());
9672 case elfcpp::Tag_ABI_FP_16bit_format:
9673 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9675 if (in_attr[i].int_value() != out_attr[i].int_value())
9676 gold_error(_("fp16 format mismatch between %s and output"),
9679 if (in_attr[i].int_value() != 0)
9680 out_attr[i].set_int_value(in_attr[i].int_value());
9683 case elfcpp::Tag_nodefaults:
9684 // This tag is set if it exists, but the value is unused (and is
9685 // typically zero). We don't actually need to do anything here -
9686 // the merge happens automatically when the type flags are merged
9689 case elfcpp::Tag_also_compatible_with:
9690 // Already done in Tag_CPU_arch.
9692 case elfcpp::Tag_conformance:
9693 // Keep the attribute if it matches. Throw it away otherwise.
9694 // No attribute means no claim to conform.
9695 if (in_attr[i].string_value() != out_attr[i].string_value())
9696 out_attr[i].set_string_value("");
9701 const char* err_object = NULL;
9703 // The "known_obj_attributes" table does contain some undefined
9704 // attributes. Ensure that there are unused.
9705 if (out_attr[i].int_value() != 0
9706 || out_attr[i].string_value() != "")
9707 err_object = "output";
9708 else if (in_attr[i].int_value() != 0
9709 || in_attr[i].string_value() != "")
9712 if (err_object != NULL)
9714 // Attribute numbers >=64 (mod 128) can be safely ignored.
9716 gold_error(_("%s: unknown mandatory EABI object attribute "
9720 gold_warning(_("%s: unknown EABI object attribute %d"),
9724 // Only pass on attributes that match in both inputs.
9725 if (!in_attr[i].matches(out_attr[i]))
9727 out_attr[i].set_int_value(0);
9728 out_attr[i].set_string_value("");
9733 // If out_attr was copied from in_attr then it won't have a type yet.
9734 if (in_attr[i].type() && !out_attr[i].type())
9735 out_attr[i].set_type(in_attr[i].type());
9738 // Merge Tag_compatibility attributes and any common GNU ones.
9739 this->attributes_section_data_->merge(name, pasd);
9741 // Check for any attributes not known on ARM.
9742 typedef Vendor_object_attributes::Other_attributes Other_attributes;
9743 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
9744 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
9745 Other_attributes* out_other_attributes =
9746 this->attributes_section_data_->other_attributes(vendor);
9747 Other_attributes::iterator out_iter = out_other_attributes->begin();
9749 while (in_iter != in_other_attributes->end()
9750 || out_iter != out_other_attributes->end())
9752 const char* err_object = NULL;
9755 // The tags for each list are in numerical order.
9756 // If the tags are equal, then merge.
9757 if (out_iter != out_other_attributes->end()
9758 && (in_iter == in_other_attributes->end()
9759 || in_iter->first > out_iter->first))
9761 // This attribute only exists in output. We can't merge, and we
9762 // don't know what the tag means, so delete it.
9763 err_object = "output";
9764 err_tag = out_iter->first;
9765 int saved_tag = out_iter->first;
9766 delete out_iter->second;
9767 out_other_attributes->erase(out_iter);
9768 out_iter = out_other_attributes->upper_bound(saved_tag);
9770 else if (in_iter != in_other_attributes->end()
9771 && (out_iter != out_other_attributes->end()
9772 || in_iter->first < out_iter->first))
9774 // This attribute only exists in input. We can't merge, and we
9775 // don't know what the tag means, so ignore it.
9777 err_tag = in_iter->first;
9780 else // The tags are equal.
9782 // As present, all attributes in the list are unknown, and
9783 // therefore can't be merged meaningfully.
9784 err_object = "output";
9785 err_tag = out_iter->first;
9787 // Only pass on attributes that match in both inputs.
9788 if (!in_iter->second->matches(*(out_iter->second)))
9790 // No match. Delete the attribute.
9791 int saved_tag = out_iter->first;
9792 delete out_iter->second;
9793 out_other_attributes->erase(out_iter);
9794 out_iter = out_other_attributes->upper_bound(saved_tag);
9798 // Matched. Keep the attribute and move to the next.
9806 // Attribute numbers >=64 (mod 128) can be safely ignored. */
9807 if ((err_tag & 127) < 64)
9809 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
9810 err_object, err_tag);
9814 gold_warning(_("%s: unknown EABI object attribute %d"),
9815 err_object, err_tag);
9821 // Stub-generation methods for Target_arm.
9823 // Make a new Arm_input_section object.
9825 template<bool big_endian>
9826 Arm_input_section<big_endian>*
9827 Target_arm<big_endian>::new_arm_input_section(
9831 Section_id sid(relobj, shndx);
9833 Arm_input_section<big_endian>* arm_input_section =
9834 new Arm_input_section<big_endian>(relobj, shndx);
9835 arm_input_section->init();
9837 // Register new Arm_input_section in map for look-up.
9838 std::pair<typename Arm_input_section_map::iterator, bool> ins =
9839 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
9841 // Make sure that it we have not created another Arm_input_section
9842 // for this input section already.
9843 gold_assert(ins.second);
9845 return arm_input_section;
9848 // Find the Arm_input_section object corresponding to the SHNDX-th input
9849 // section of RELOBJ.
9851 template<bool big_endian>
9852 Arm_input_section<big_endian>*
9853 Target_arm<big_endian>::find_arm_input_section(
9855 unsigned int shndx) const
9857 Section_id sid(relobj, shndx);
9858 typename Arm_input_section_map::const_iterator p =
9859 this->arm_input_section_map_.find(sid);
9860 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
9863 // Make a new stub table.
9865 template<bool big_endian>
9866 Stub_table<big_endian>*
9867 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
9869 Stub_table<big_endian>* stub_table =
9870 new Stub_table<big_endian>(owner);
9871 this->stub_tables_.push_back(stub_table);
9873 stub_table->set_address(owner->address() + owner->data_size());
9874 stub_table->set_file_offset(owner->offset() + owner->data_size());
9875 stub_table->finalize_data_size();
9880 // Scan a relocation for stub generation.
9882 template<bool big_endian>
9884 Target_arm<big_endian>::scan_reloc_for_stub(
9885 const Relocate_info<32, big_endian>* relinfo,
9886 unsigned int r_type,
9887 const Sized_symbol<32>* gsym,
9889 const Symbol_value<32>* psymval,
9890 elfcpp::Elf_types<32>::Elf_Swxword addend,
9891 Arm_address address)
9893 typedef typename Target_arm<big_endian>::Relocate Relocate;
9895 const Arm_relobj<big_endian>* arm_relobj =
9896 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9898 bool target_is_thumb;
9899 Symbol_value<32> symval;
9902 // This is a global symbol. Determine if we use PLT and if the
9903 // final target is THUMB.
9904 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
9906 // This uses a PLT, change the symbol value.
9907 symval.set_output_value(this->plt_section()->address()
9908 + gsym->plt_offset());
9910 target_is_thumb = false;
9912 else if (gsym->is_undefined())
9913 // There is no need to generate a stub symbol is undefined.
9918 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
9919 || (gsym->type() == elfcpp::STT_FUNC
9920 && !gsym->is_undefined()
9921 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
9926 // This is a local symbol. Determine if the final target is THUMB.
9927 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
9930 // Strip LSB if this points to a THUMB target.
9931 const Arm_reloc_property* reloc_property =
9932 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9933 gold_assert(reloc_property != NULL);
9935 && reloc_property->uses_thumb_bit()
9936 && ((psymval->value(arm_relobj, 0) & 1) != 0))
9938 Arm_address stripped_value =
9939 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
9940 symval.set_output_value(stripped_value);
9944 // Get the symbol value.
9945 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
9947 // Owing to pipelining, the PC relative branches below actually skip
9948 // two instructions when the branch offset is 0.
9949 Arm_address destination;
9952 case elfcpp::R_ARM_CALL:
9953 case elfcpp::R_ARM_JUMP24:
9954 case elfcpp::R_ARM_PLT32:
9956 destination = value + addend + 8;
9958 case elfcpp::R_ARM_THM_CALL:
9959 case elfcpp::R_ARM_THM_XPC22:
9960 case elfcpp::R_ARM_THM_JUMP24:
9961 case elfcpp::R_ARM_THM_JUMP19:
9963 destination = value + addend + 4;
9969 Reloc_stub* stub = NULL;
9970 Stub_type stub_type =
9971 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
9973 if (stub_type != arm_stub_none)
9975 // Try looking up an existing stub from a stub table.
9976 Stub_table<big_endian>* stub_table =
9977 arm_relobj->stub_table(relinfo->data_shndx);
9978 gold_assert(stub_table != NULL);
9980 // Locate stub by destination.
9981 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
9983 // Create a stub if there is not one already
9984 stub = stub_table->find_reloc_stub(stub_key);
9987 // create a new stub and add it to stub table.
9988 stub = this->stub_factory().make_reloc_stub(stub_type);
9989 stub_table->add_reloc_stub(stub, stub_key);
9992 // Record the destination address.
9993 stub->set_destination_address(destination
9994 | (target_is_thumb ? 1 : 0));
9997 // For Cortex-A8, we need to record a relocation at 4K page boundary.
9998 if (this->fix_cortex_a8_
9999 && (r_type == elfcpp::R_ARM_THM_JUMP24
10000 || r_type == elfcpp::R_ARM_THM_JUMP19
10001 || r_type == elfcpp::R_ARM_THM_CALL
10002 || r_type == elfcpp::R_ARM_THM_XPC22)
10003 && (address & 0xfffU) == 0xffeU)
10005 // Found a candidate. Note we haven't checked the destination is
10006 // within 4K here: if we do so (and don't create a record) we can't
10007 // tell that a branch should have been relocated when scanning later.
10008 this->cortex_a8_relocs_info_[address] =
10009 new Cortex_a8_reloc(stub, r_type,
10010 destination | (target_is_thumb ? 1 : 0));
10014 // This function scans a relocation sections for stub generation.
10015 // The template parameter Relocate must be a class type which provides
10016 // a single function, relocate(), which implements the machine
10017 // specific part of a relocation.
10019 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
10020 // SHT_REL or SHT_RELA.
10022 // PRELOCS points to the relocation data. RELOC_COUNT is the number
10023 // of relocs. OUTPUT_SECTION is the output section.
10024 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
10025 // mapped to output offsets.
10027 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
10028 // VIEW_SIZE is the size. These refer to the input section, unless
10029 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
10030 // the output section.
10032 template<bool big_endian>
10033 template<int sh_type>
10035 Target_arm<big_endian>::scan_reloc_section_for_stubs(
10036 const Relocate_info<32, big_endian>* relinfo,
10037 const unsigned char* prelocs,
10038 size_t reloc_count,
10039 Output_section* output_section,
10040 bool needs_special_offset_handling,
10041 const unsigned char* view,
10042 elfcpp::Elf_types<32>::Elf_Addr view_address,
10045 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
10046 const int reloc_size =
10047 Reloc_types<sh_type, 32, big_endian>::reloc_size;
10049 Arm_relobj<big_endian>* arm_object =
10050 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10051 unsigned int local_count = arm_object->local_symbol_count();
10053 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
10055 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
10057 Reltype reloc(prelocs);
10059 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
10060 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
10061 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
10063 r_type = this->get_real_reloc_type(r_type);
10065 // Only a few relocation types need stubs.
10066 if ((r_type != elfcpp::R_ARM_CALL)
10067 && (r_type != elfcpp::R_ARM_JUMP24)
10068 && (r_type != elfcpp::R_ARM_PLT32)
10069 && (r_type != elfcpp::R_ARM_THM_CALL)
10070 && (r_type != elfcpp::R_ARM_THM_XPC22)
10071 && (r_type != elfcpp::R_ARM_THM_JUMP24)
10072 && (r_type != elfcpp::R_ARM_THM_JUMP19)
10073 && (r_type != elfcpp::R_ARM_V4BX))
10076 section_offset_type offset =
10077 convert_to_section_size_type(reloc.get_r_offset());
10079 if (needs_special_offset_handling)
10081 offset = output_section->output_offset(relinfo->object,
10082 relinfo->data_shndx,
10088 // Create a v4bx stub if --fix-v4bx-interworking is used.
10089 if (r_type == elfcpp::R_ARM_V4BX)
10091 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
10093 // Get the BX instruction.
10094 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
10095 const Valtype* wv =
10096 reinterpret_cast<const Valtype*>(view + offset);
10097 elfcpp::Elf_types<32>::Elf_Swxword insn =
10098 elfcpp::Swap<32, big_endian>::readval(wv);
10099 const uint32_t reg = (insn & 0xf);
10103 // Try looking up an existing stub from a stub table.
10104 Stub_table<big_endian>* stub_table =
10105 arm_object->stub_table(relinfo->data_shndx);
10106 gold_assert(stub_table != NULL);
10108 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
10110 // create a new stub and add it to stub table.
10111 Arm_v4bx_stub* stub =
10112 this->stub_factory().make_arm_v4bx_stub(reg);
10113 gold_assert(stub != NULL);
10114 stub_table->add_arm_v4bx_stub(stub);
10122 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
10123 elfcpp::Elf_types<32>::Elf_Swxword addend =
10124 stub_addend_reader(r_type, view + offset, reloc);
10126 const Sized_symbol<32>* sym;
10128 Symbol_value<32> symval;
10129 const Symbol_value<32> *psymval;
10130 if (r_sym < local_count)
10133 psymval = arm_object->local_symbol(r_sym);
10135 // If the local symbol belongs to a section we are discarding,
10136 // and that section is a debug section, try to find the
10137 // corresponding kept section and map this symbol to its
10138 // counterpart in the kept section. The symbol must not
10139 // correspond to a section we are folding.
10141 unsigned int shndx = psymval->input_shndx(&is_ordinary);
10143 && shndx != elfcpp::SHN_UNDEF
10144 && !arm_object->is_section_included(shndx)
10145 && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
10147 if (comdat_behavior == CB_UNDETERMINED)
10150 arm_object->section_name(relinfo->data_shndx);
10151 comdat_behavior = get_comdat_behavior(name.c_str());
10153 if (comdat_behavior == CB_PRETEND)
10156 typename elfcpp::Elf_types<32>::Elf_Addr value =
10157 arm_object->map_to_kept_section(shndx, &found);
10159 symval.set_output_value(value + psymval->input_value());
10161 symval.set_output_value(0);
10165 symval.set_output_value(0);
10167 symval.set_no_output_symtab_entry();
10173 const Symbol* gsym = arm_object->global_symbol(r_sym);
10174 gold_assert(gsym != NULL);
10175 if (gsym->is_forwarder())
10176 gsym = relinfo->symtab->resolve_forwards(gsym);
10178 sym = static_cast<const Sized_symbol<32>*>(gsym);
10179 if (sym->has_symtab_index())
10180 symval.set_output_symtab_index(sym->symtab_index());
10182 symval.set_no_output_symtab_entry();
10184 // We need to compute the would-be final value of this global
10186 const Symbol_table* symtab = relinfo->symtab;
10187 const Sized_symbol<32>* sized_symbol =
10188 symtab->get_sized_symbol<32>(gsym);
10189 Symbol_table::Compute_final_value_status status;
10190 Arm_address value =
10191 symtab->compute_final_value<32>(sized_symbol, &status);
10193 // Skip this if the symbol has not output section.
10194 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
10197 symval.set_output_value(value);
10201 // If symbol is a section symbol, we don't know the actual type of
10202 // destination. Give up.
10203 if (psymval->is_section_symbol())
10206 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
10207 addend, view_address + offset);
10211 // Scan an input section for stub generation.
10213 template<bool big_endian>
10215 Target_arm<big_endian>::scan_section_for_stubs(
10216 const Relocate_info<32, big_endian>* relinfo,
10217 unsigned int sh_type,
10218 const unsigned char* prelocs,
10219 size_t reloc_count,
10220 Output_section* output_section,
10221 bool needs_special_offset_handling,
10222 const unsigned char* view,
10223 Arm_address view_address,
10224 section_size_type view_size)
10226 if (sh_type == elfcpp::SHT_REL)
10227 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
10232 needs_special_offset_handling,
10236 else if (sh_type == elfcpp::SHT_RELA)
10237 // We do not support RELA type relocations yet. This is provided for
10239 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
10244 needs_special_offset_handling,
10249 gold_unreachable();
10252 // Group input sections for stub generation.
10254 // We goup input sections in an output sections so that the total size,
10255 // including any padding space due to alignment is smaller than GROUP_SIZE
10256 // unless the only input section in group is bigger than GROUP_SIZE already.
10257 // Then an ARM stub table is created to follow the last input section
10258 // in group. For each group an ARM stub table is created an is placed
10259 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
10260 // extend the group after the stub table.
10262 template<bool big_endian>
10264 Target_arm<big_endian>::group_sections(
10266 section_size_type group_size,
10267 bool stubs_always_after_branch)
10269 // Group input sections and insert stub table
10270 Layout::Section_list section_list;
10271 layout->get_allocated_sections(§ion_list);
10272 for (Layout::Section_list::const_iterator p = section_list.begin();
10273 p != section_list.end();
10276 Arm_output_section<big_endian>* output_section =
10277 Arm_output_section<big_endian>::as_arm_output_section(*p);
10278 output_section->group_sections(group_size, stubs_always_after_branch,
10283 // Relaxation hook. This is where we do stub generation.
10285 template<bool big_endian>
10287 Target_arm<big_endian>::do_relax(
10289 const Input_objects* input_objects,
10290 Symbol_table* symtab,
10293 // No need to generate stubs if this is a relocatable link.
10294 gold_assert(!parameters->options().relocatable());
10296 // If this is the first pass, we need to group input sections into
10298 bool done_exidx_fixup = false;
10301 // Determine the stub group size. The group size is the absolute
10302 // value of the parameter --stub-group-size. If --stub-group-size
10303 // is passed a negative value, we restict stubs to be always after
10304 // the stubbed branches.
10305 int32_t stub_group_size_param =
10306 parameters->options().stub_group_size();
10307 bool stubs_always_after_branch = stub_group_size_param < 0;
10308 section_size_type stub_group_size = abs(stub_group_size_param);
10310 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
10311 // page as the first half of a 32-bit branch straddling two 4K pages.
10312 // This is a crude way of enforcing that.
10313 if (this->fix_cortex_a8_)
10314 stubs_always_after_branch = true;
10316 if (stub_group_size == 1)
10319 // Thumb branch range is +-4MB has to be used as the default
10320 // maximum size (a given section can contain both ARM and Thumb
10321 // code, so the worst case has to be taken into account). If we are
10322 // fixing cortex-a8 errata, the branch range has to be even smaller,
10323 // since wide conditional branch has a range of +-1MB only.
10325 // This value is 24K less than that, which allows for 2025
10326 // 12-byte stubs. If we exceed that, then we will fail to link.
10327 // The user will have to relink with an explicit group size
10329 if (this->fix_cortex_a8_)
10330 stub_group_size = 1024276;
10332 stub_group_size = 4170000;
10335 group_sections(layout, stub_group_size, stubs_always_after_branch);
10337 // Also fix .ARM.exidx section coverage.
10338 Output_section* os = layout->find_output_section(".ARM.exidx");
10339 if (os != NULL && os->type() == elfcpp::SHT_ARM_EXIDX)
10341 Arm_output_section<big_endian>* exidx_output_section =
10342 Arm_output_section<big_endian>::as_arm_output_section(os);
10343 this->fix_exidx_coverage(layout, exidx_output_section, symtab);
10344 done_exidx_fixup = true;
10348 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
10349 // beginning of each relaxation pass, just blow away all the stubs.
10350 // Alternatively, we could selectively remove only the stubs and reloc
10351 // information for code sections that have moved since the last pass.
10352 // That would require more book-keeping.
10353 typedef typename Stub_table_list::iterator Stub_table_iterator;
10354 if (this->fix_cortex_a8_)
10356 // Clear all Cortex-A8 reloc information.
10357 for (typename Cortex_a8_relocs_info::const_iterator p =
10358 this->cortex_a8_relocs_info_.begin();
10359 p != this->cortex_a8_relocs_info_.end();
10362 this->cortex_a8_relocs_info_.clear();
10364 // Remove all Cortex-A8 stubs.
10365 for (Stub_table_iterator sp = this->stub_tables_.begin();
10366 sp != this->stub_tables_.end();
10368 (*sp)->remove_all_cortex_a8_stubs();
10371 // Scan relocs for relocation stubs
10372 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10373 op != input_objects->relobj_end();
10376 Arm_relobj<big_endian>* arm_relobj =
10377 Arm_relobj<big_endian>::as_arm_relobj(*op);
10378 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
10381 // Check all stub tables to see if any of them have their data sizes
10382 // or addresses alignments changed. These are the only things that
10384 bool any_stub_table_changed = false;
10385 Unordered_set<const Output_section*> sections_needing_adjustment;
10386 for (Stub_table_iterator sp = this->stub_tables_.begin();
10387 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10390 if ((*sp)->update_data_size_and_addralign())
10392 // Update data size of stub table owner.
10393 Arm_input_section<big_endian>* owner = (*sp)->owner();
10394 uint64_t address = owner->address();
10395 off_t offset = owner->offset();
10396 owner->reset_address_and_file_offset();
10397 owner->set_address_and_file_offset(address, offset);
10399 sections_needing_adjustment.insert(owner->output_section());
10400 any_stub_table_changed = true;
10404 // Output_section_data::output_section() returns a const pointer but we
10405 // need to update output sections, so we record all output sections needing
10406 // update above and scan the sections here to find out what sections need
10408 for(Layout::Section_list::const_iterator p = layout->section_list().begin();
10409 p != layout->section_list().end();
10412 if (sections_needing_adjustment.find(*p)
10413 != sections_needing_adjustment.end())
10414 (*p)->set_section_offsets_need_adjustment();
10417 // Stop relaxation if no EXIDX fix-up and no stub table change.
10418 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
10420 // Finalize the stubs in the last relaxation pass.
10421 if (!continue_relaxation)
10423 for (Stub_table_iterator sp = this->stub_tables_.begin();
10424 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10426 (*sp)->finalize_stubs();
10428 // Update output local symbol counts of objects if necessary.
10429 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10430 op != input_objects->relobj_end();
10433 Arm_relobj<big_endian>* arm_relobj =
10434 Arm_relobj<big_endian>::as_arm_relobj(*op);
10436 // Update output local symbol counts. We need to discard local
10437 // symbols defined in parts of input sections that are discarded by
10439 if (arm_relobj->output_local_symbol_count_needs_update())
10440 arm_relobj->update_output_local_symbol_count();
10444 return continue_relaxation;
10447 // Relocate a stub.
10449 template<bool big_endian>
10451 Target_arm<big_endian>::relocate_stub(
10453 const Relocate_info<32, big_endian>* relinfo,
10454 Output_section* output_section,
10455 unsigned char* view,
10456 Arm_address address,
10457 section_size_type view_size)
10460 const Stub_template* stub_template = stub->stub_template();
10461 for (size_t i = 0; i < stub_template->reloc_count(); i++)
10463 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
10464 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
10466 unsigned int r_type = insn->r_type();
10467 section_size_type reloc_offset = stub_template->reloc_offset(i);
10468 section_size_type reloc_size = insn->size();
10469 gold_assert(reloc_offset + reloc_size <= view_size);
10471 // This is the address of the stub destination.
10472 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
10473 Symbol_value<32> symval;
10474 symval.set_output_value(target);
10476 // Synthesize a fake reloc just in case. We don't have a symbol so
10478 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
10479 memset(reloc_buffer, 0, sizeof(reloc_buffer));
10480 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
10481 reloc_write.put_r_offset(reloc_offset);
10482 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
10483 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
10485 relocate.relocate(relinfo, this, output_section,
10486 this->fake_relnum_for_stubs, rel, r_type,
10487 NULL, &symval, view + reloc_offset,
10488 address + reloc_offset, reloc_size);
10492 // Determine whether an object attribute tag takes an integer, a
10495 template<bool big_endian>
10497 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
10499 if (tag == Object_attribute::Tag_compatibility)
10500 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10501 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
10502 else if (tag == elfcpp::Tag_nodefaults)
10503 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10504 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
10505 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
10506 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
10508 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
10510 return ((tag & 1) != 0
10511 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
10512 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
10515 // Reorder attributes.
10517 // The ABI defines that Tag_conformance should be emitted first, and that
10518 // Tag_nodefaults should be second (if either is defined). This sets those
10519 // two positions, and bumps up the position of all the remaining tags to
10522 template<bool big_endian>
10524 Target_arm<big_endian>::do_attributes_order(int num) const
10526 // Reorder the known object attributes in output. We want to move
10527 // Tag_conformance to position 4 and Tag_conformance to position 5
10528 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
10530 return elfcpp::Tag_conformance;
10532 return elfcpp::Tag_nodefaults;
10533 if ((num - 2) < elfcpp::Tag_nodefaults)
10535 if ((num - 1) < elfcpp::Tag_conformance)
10540 // Scan a span of THUMB code for Cortex-A8 erratum.
10542 template<bool big_endian>
10544 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
10545 Arm_relobj<big_endian>* arm_relobj,
10546 unsigned int shndx,
10547 section_size_type span_start,
10548 section_size_type span_end,
10549 const unsigned char* view,
10550 Arm_address address)
10552 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
10554 // The opcode is BLX.W, BL.W, B.W, Bcc.W
10555 // The branch target is in the same 4KB region as the
10556 // first half of the branch.
10557 // The instruction before the branch is a 32-bit
10558 // length non-branch instruction.
10559 section_size_type i = span_start;
10560 bool last_was_32bit = false;
10561 bool last_was_branch = false;
10562 while (i < span_end)
10564 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10565 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
10566 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
10567 bool is_blx = false, is_b = false;
10568 bool is_bl = false, is_bcc = false;
10570 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
10573 // Load the rest of the insn (in manual-friendly order).
10574 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
10576 // Encoding T4: B<c>.W.
10577 is_b = (insn & 0xf800d000U) == 0xf0009000U;
10578 // Encoding T1: BL<c>.W.
10579 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
10580 // Encoding T2: BLX<c>.W.
10581 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
10582 // Encoding T3: B<c>.W (not permitted in IT block).
10583 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
10584 && (insn & 0x07f00000U) != 0x03800000U);
10587 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
10589 // If this instruction is a 32-bit THUMB branch that crosses a 4K
10590 // page boundary and it follows 32-bit non-branch instruction,
10591 // we need to work around.
10592 if (is_32bit_branch
10593 && ((address + i) & 0xfffU) == 0xffeU
10595 && !last_was_branch)
10597 // Check to see if there is a relocation stub for this branch.
10598 bool force_target_arm = false;
10599 bool force_target_thumb = false;
10600 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
10601 Cortex_a8_relocs_info::const_iterator p =
10602 this->cortex_a8_relocs_info_.find(address + i);
10604 if (p != this->cortex_a8_relocs_info_.end())
10606 cortex_a8_reloc = p->second;
10607 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
10609 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10610 && !target_is_thumb)
10611 force_target_arm = true;
10612 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10613 && target_is_thumb)
10614 force_target_thumb = true;
10618 Stub_type stub_type = arm_stub_none;
10620 // Check if we have an offending branch instruction.
10621 uint16_t upper_insn = (insn >> 16) & 0xffffU;
10622 uint16_t lower_insn = insn & 0xffffU;
10623 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10625 if (cortex_a8_reloc != NULL
10626 && cortex_a8_reloc->reloc_stub() != NULL)
10627 // We've already made a stub for this instruction, e.g.
10628 // it's a long branch or a Thumb->ARM stub. Assume that
10629 // stub will suffice to work around the A8 erratum (see
10630 // setting of always_after_branch above).
10634 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
10636 stub_type = arm_stub_a8_veneer_b_cond;
10638 else if (is_b || is_bl || is_blx)
10640 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
10645 stub_type = (is_blx
10646 ? arm_stub_a8_veneer_blx
10648 ? arm_stub_a8_veneer_bl
10649 : arm_stub_a8_veneer_b));
10652 if (stub_type != arm_stub_none)
10654 Arm_address pc_for_insn = address + i + 4;
10656 // The original instruction is a BL, but the target is
10657 // an ARM instruction. If we were not making a stub,
10658 // the BL would have been converted to a BLX. Use the
10659 // BLX stub instead in that case.
10660 if (this->may_use_blx() && force_target_arm
10661 && stub_type == arm_stub_a8_veneer_bl)
10663 stub_type = arm_stub_a8_veneer_blx;
10667 // Conversely, if the original instruction was
10668 // BLX but the target is Thumb mode, use the BL stub.
10669 else if (force_target_thumb
10670 && stub_type == arm_stub_a8_veneer_blx)
10672 stub_type = arm_stub_a8_veneer_bl;
10680 // If we found a relocation, use the proper destination,
10681 // not the offset in the (unrelocated) instruction.
10682 // Note this is always done if we switched the stub type above.
10683 if (cortex_a8_reloc != NULL)
10684 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
10686 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
10688 // Add a new stub if destination address in in the same page.
10689 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
10691 Cortex_a8_stub* stub =
10692 this->stub_factory_.make_cortex_a8_stub(stub_type,
10696 Stub_table<big_endian>* stub_table =
10697 arm_relobj->stub_table(shndx);
10698 gold_assert(stub_table != NULL);
10699 stub_table->add_cortex_a8_stub(address + i, stub);
10704 i += insn_32bit ? 4 : 2;
10705 last_was_32bit = insn_32bit;
10706 last_was_branch = is_32bit_branch;
10710 // Apply the Cortex-A8 workaround.
10712 template<bool big_endian>
10714 Target_arm<big_endian>::apply_cortex_a8_workaround(
10715 const Cortex_a8_stub* stub,
10716 Arm_address stub_address,
10717 unsigned char* insn_view,
10718 Arm_address insn_address)
10720 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10721 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
10722 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
10723 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
10724 off_t branch_offset = stub_address - (insn_address + 4);
10726 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10727 switch (stub->stub_template()->type())
10729 case arm_stub_a8_veneer_b_cond:
10730 gold_assert(!utils::has_overflow<21>(branch_offset));
10731 upper_insn = RelocFuncs::thumb32_cond_branch_upper(upper_insn,
10733 lower_insn = RelocFuncs::thumb32_cond_branch_lower(lower_insn,
10737 case arm_stub_a8_veneer_b:
10738 case arm_stub_a8_veneer_bl:
10739 case arm_stub_a8_veneer_blx:
10740 if ((lower_insn & 0x5000U) == 0x4000U)
10741 // For a BLX instruction, make sure that the relocation is
10742 // rounded up to a word boundary. This follows the semantics of
10743 // the instruction which specifies that bit 1 of the target
10744 // address will come from bit 1 of the base address.
10745 branch_offset = (branch_offset + 2) & ~3;
10747 // Put BRANCH_OFFSET back into the insn.
10748 gold_assert(!utils::has_overflow<25>(branch_offset));
10749 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
10750 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
10754 gold_unreachable();
10757 // Put the relocated value back in the object file:
10758 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
10759 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
10762 template<bool big_endian>
10763 class Target_selector_arm : public Target_selector
10766 Target_selector_arm()
10767 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
10768 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
10772 do_instantiate_target()
10773 { return new Target_arm<big_endian>(); }
10776 // Fix .ARM.exidx section coverage.
10778 template<bool big_endian>
10780 Target_arm<big_endian>::fix_exidx_coverage(
10782 Arm_output_section<big_endian>* exidx_section,
10783 Symbol_table* symtab)
10785 // We need to look at all the input sections in output in ascending
10786 // order of of output address. We do that by building a sorted list
10787 // of output sections by addresses. Then we looks at the output sections
10788 // in order. The input sections in an output section are already sorted
10789 // by addresses within the output section.
10791 typedef std::set<Output_section*, output_section_address_less_than>
10792 Sorted_output_section_list;
10793 Sorted_output_section_list sorted_output_sections;
10794 Layout::Section_list section_list;
10795 layout->get_allocated_sections(§ion_list);
10796 for (Layout::Section_list::const_iterator p = section_list.begin();
10797 p != section_list.end();
10800 // We only care about output sections that contain executable code.
10801 if (((*p)->flags() & elfcpp::SHF_EXECINSTR) != 0)
10802 sorted_output_sections.insert(*p);
10805 // Go over the output sections in ascending order of output addresses.
10806 typedef typename Arm_output_section<big_endian>::Text_section_list
10808 Text_section_list sorted_text_sections;
10809 for(typename Sorted_output_section_list::iterator p =
10810 sorted_output_sections.begin();
10811 p != sorted_output_sections.end();
10814 Arm_output_section<big_endian>* arm_output_section =
10815 Arm_output_section<big_endian>::as_arm_output_section(*p);
10816 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
10819 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab);
10822 Target_selector_arm<false> target_selector_arm;
10823 Target_selector_arm<true> target_selector_armbe;
10825 } // End anonymous namespace.