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);
2057 if (attr->int_value() == elfcpp::TAG_CPU_ARCH_V6_M
2058 || attr->int_value() == elfcpp::TAG_CPU_ARCH_V6S_M)
2060 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2061 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2063 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2064 return attr->int_value() == 'M';
2067 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2069 may_use_arm_nop() const
2071 Object_attribute* attr =
2072 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2073 int arch = attr->int_value();
2074 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2075 || arch == elfcpp::TAG_CPU_ARCH_V6K
2076 || arch == elfcpp::TAG_CPU_ARCH_V7
2077 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2080 // Whether we have THUMB-2 NOP.W instruction.
2082 may_use_thumb2_nop() const
2084 Object_attribute* attr =
2085 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2086 int arch = attr->int_value();
2087 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2088 || arch == elfcpp::TAG_CPU_ARCH_V7
2089 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2092 // Process the relocations to determine unreferenced sections for
2093 // garbage collection.
2095 gc_process_relocs(Symbol_table* symtab,
2097 Sized_relobj<32, big_endian>* object,
2098 unsigned int data_shndx,
2099 unsigned int sh_type,
2100 const unsigned char* prelocs,
2102 Output_section* output_section,
2103 bool needs_special_offset_handling,
2104 size_t local_symbol_count,
2105 const unsigned char* plocal_symbols);
2107 // Scan the relocations to look for symbol adjustments.
2109 scan_relocs(Symbol_table* symtab,
2111 Sized_relobj<32, big_endian>* object,
2112 unsigned int data_shndx,
2113 unsigned int sh_type,
2114 const unsigned char* prelocs,
2116 Output_section* output_section,
2117 bool needs_special_offset_handling,
2118 size_t local_symbol_count,
2119 const unsigned char* plocal_symbols);
2121 // Finalize the sections.
2123 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2125 // Return the value to use for a dynamic symbol which requires special
2128 do_dynsym_value(const Symbol*) const;
2130 // Relocate a section.
2132 relocate_section(const Relocate_info<32, big_endian>*,
2133 unsigned int sh_type,
2134 const unsigned char* prelocs,
2136 Output_section* output_section,
2137 bool needs_special_offset_handling,
2138 unsigned char* view,
2139 Arm_address view_address,
2140 section_size_type view_size,
2141 const Reloc_symbol_changes*);
2143 // Scan the relocs during a relocatable link.
2145 scan_relocatable_relocs(Symbol_table* symtab,
2147 Sized_relobj<32, big_endian>* object,
2148 unsigned int data_shndx,
2149 unsigned int sh_type,
2150 const unsigned char* prelocs,
2152 Output_section* output_section,
2153 bool needs_special_offset_handling,
2154 size_t local_symbol_count,
2155 const unsigned char* plocal_symbols,
2156 Relocatable_relocs*);
2158 // Relocate a section during a relocatable link.
2160 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
2161 unsigned int sh_type,
2162 const unsigned char* prelocs,
2164 Output_section* output_section,
2165 off_t offset_in_output_section,
2166 const Relocatable_relocs*,
2167 unsigned char* view,
2168 Arm_address view_address,
2169 section_size_type view_size,
2170 unsigned char* reloc_view,
2171 section_size_type reloc_view_size);
2173 // Return whether SYM is defined by the ABI.
2175 do_is_defined_by_abi(Symbol* sym) const
2176 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2178 // Return whether there is a GOT section.
2180 has_got_section() const
2181 { return this->got_ != NULL; }
2183 // Return the size of the GOT section.
2187 gold_assert(this->got_ != NULL);
2188 return this->got_->data_size();
2191 // Map platform-specific reloc types
2193 get_real_reloc_type (unsigned int r_type);
2196 // Methods to support stub-generations.
2199 // Return the stub factory
2201 stub_factory() const
2202 { return this->stub_factory_; }
2204 // Make a new Arm_input_section object.
2205 Arm_input_section<big_endian>*
2206 new_arm_input_section(Relobj*, unsigned int);
2208 // Find the Arm_input_section object corresponding to the SHNDX-th input
2209 // section of RELOBJ.
2210 Arm_input_section<big_endian>*
2211 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2213 // Make a new Stub_table
2214 Stub_table<big_endian>*
2215 new_stub_table(Arm_input_section<big_endian>*);
2217 // Scan a section for stub generation.
2219 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2220 const unsigned char*, size_t, Output_section*,
2221 bool, const unsigned char*, Arm_address,
2226 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2227 Output_section*, unsigned char*, Arm_address,
2230 // Get the default ARM target.
2231 static Target_arm<big_endian>*
2234 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2235 && parameters->target().is_big_endian() == big_endian);
2236 return static_cast<Target_arm<big_endian>*>(
2237 parameters->sized_target<32, big_endian>());
2240 // Whether NAME belongs to a mapping symbol.
2242 is_mapping_symbol_name(const char* name)
2246 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2247 && (name[2] == '\0' || name[2] == '.'));
2250 // Whether we work around the Cortex-A8 erratum.
2252 fix_cortex_a8() const
2253 { return this->fix_cortex_a8_; }
2255 // Whether we fix R_ARM_V4BX relocation.
2257 // 1 - replace with MOV instruction (armv4 target)
2258 // 2 - make interworking veneer (>= armv4t targets only)
2259 General_options::Fix_v4bx
2261 { return parameters->options().fix_v4bx(); }
2263 // Scan a span of THUMB code section for Cortex-A8 erratum.
2265 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2266 section_size_type, section_size_type,
2267 const unsigned char*, Arm_address);
2269 // Apply Cortex-A8 workaround to a branch.
2271 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2272 unsigned char*, Arm_address);
2275 // Make an ELF object.
2277 do_make_elf_object(const std::string&, Input_file*, off_t,
2278 const elfcpp::Ehdr<32, big_endian>& ehdr);
2281 do_make_elf_object(const std::string&, Input_file*, off_t,
2282 const elfcpp::Ehdr<32, !big_endian>&)
2283 { gold_unreachable(); }
2286 do_make_elf_object(const std::string&, Input_file*, off_t,
2287 const elfcpp::Ehdr<64, false>&)
2288 { gold_unreachable(); }
2291 do_make_elf_object(const std::string&, Input_file*, off_t,
2292 const elfcpp::Ehdr<64, true>&)
2293 { gold_unreachable(); }
2295 // Make an output section.
2297 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2298 elfcpp::Elf_Xword flags)
2299 { return new Arm_output_section<big_endian>(name, type, flags); }
2302 do_adjust_elf_header(unsigned char* view, int len) const;
2304 // We only need to generate stubs, and hence perform relaxation if we are
2305 // not doing relocatable linking.
2307 do_may_relax() const
2308 { return !parameters->options().relocatable(); }
2311 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
2313 // Determine whether an object attribute tag takes an integer, a
2316 do_attribute_arg_type(int tag) const;
2318 // Reorder tags during output.
2320 do_attributes_order(int num) const;
2322 // This is called when the target is selected as the default.
2324 do_select_as_default_target()
2326 // No locking is required since there should only be one default target.
2327 // We cannot have both the big-endian and little-endian ARM targets
2329 gold_assert(arm_reloc_property_table == NULL);
2330 arm_reloc_property_table = new Arm_reloc_property_table();
2334 // The class which scans relocations.
2339 : issued_non_pic_error_(false)
2343 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2344 Sized_relobj<32, big_endian>* object,
2345 unsigned int data_shndx,
2346 Output_section* output_section,
2347 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2348 const elfcpp::Sym<32, big_endian>& lsym);
2351 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2352 Sized_relobj<32, big_endian>* object,
2353 unsigned int data_shndx,
2354 Output_section* output_section,
2355 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2359 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2360 Sized_relobj<32, big_endian>* ,
2363 const elfcpp::Rel<32, big_endian>& ,
2365 const elfcpp::Sym<32, big_endian>&)
2369 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2370 Sized_relobj<32, big_endian>* ,
2373 const elfcpp::Rel<32, big_endian>& ,
2374 unsigned int , Symbol*)
2379 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
2380 unsigned int r_type);
2383 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
2384 unsigned int r_type, Symbol*);
2387 check_non_pic(Relobj*, unsigned int r_type);
2389 // Almost identical to Symbol::needs_plt_entry except that it also
2390 // handles STT_ARM_TFUNC.
2392 symbol_needs_plt_entry(const Symbol* sym)
2394 // An undefined symbol from an executable does not need a PLT entry.
2395 if (sym->is_undefined() && !parameters->options().shared())
2398 return (!parameters->doing_static_link()
2399 && (sym->type() == elfcpp::STT_FUNC
2400 || sym->type() == elfcpp::STT_ARM_TFUNC)
2401 && (sym->is_from_dynobj()
2402 || sym->is_undefined()
2403 || sym->is_preemptible()));
2406 // Whether we have issued an error about a non-PIC compilation.
2407 bool issued_non_pic_error_;
2410 // The class which implements relocation.
2420 // Return whether the static relocation needs to be applied.
2422 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2425 Output_section* output_section);
2427 // Do a relocation. Return false if the caller should not issue
2428 // any warnings about this relocation.
2430 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2431 Output_section*, size_t relnum,
2432 const elfcpp::Rel<32, big_endian>&,
2433 unsigned int r_type, const Sized_symbol<32>*,
2434 const Symbol_value<32>*,
2435 unsigned char*, Arm_address,
2438 // Return whether we want to pass flag NON_PIC_REF for this
2439 // reloc. This means the relocation type accesses a symbol not via
2442 reloc_is_non_pic (unsigned int r_type)
2446 // These relocation types reference GOT or PLT entries explicitly.
2447 case elfcpp::R_ARM_GOT_BREL:
2448 case elfcpp::R_ARM_GOT_ABS:
2449 case elfcpp::R_ARM_GOT_PREL:
2450 case elfcpp::R_ARM_GOT_BREL12:
2451 case elfcpp::R_ARM_PLT32_ABS:
2452 case elfcpp::R_ARM_TLS_GD32:
2453 case elfcpp::R_ARM_TLS_LDM32:
2454 case elfcpp::R_ARM_TLS_IE32:
2455 case elfcpp::R_ARM_TLS_IE12GP:
2457 // These relocate types may use PLT entries.
2458 case elfcpp::R_ARM_CALL:
2459 case elfcpp::R_ARM_THM_CALL:
2460 case elfcpp::R_ARM_JUMP24:
2461 case elfcpp::R_ARM_THM_JUMP24:
2462 case elfcpp::R_ARM_THM_JUMP19:
2463 case elfcpp::R_ARM_PLT32:
2464 case elfcpp::R_ARM_THM_XPC22:
2465 case elfcpp::R_ARM_PREL31:
2466 case elfcpp::R_ARM_SBREL31:
2475 // Do a TLS relocation.
2476 inline typename Arm_relocate_functions<big_endian>::Status
2477 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2478 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2479 const Sized_symbol<32>*, const Symbol_value<32>*,
2480 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2485 // A class which returns the size required for a relocation type,
2486 // used while scanning relocs during a relocatable link.
2487 class Relocatable_size_for_reloc
2491 get_size_for_reloc(unsigned int, Relobj*);
2494 // Adjust TLS relocation type based on the options and whether this
2495 // is a local symbol.
2496 static tls::Tls_optimization
2497 optimize_tls_reloc(bool is_final, int r_type);
2499 // Get the GOT section, creating it if necessary.
2500 Arm_output_data_got<big_endian>*
2501 got_section(Symbol_table*, Layout*);
2503 // Get the GOT PLT section.
2505 got_plt_section() const
2507 gold_assert(this->got_plt_ != NULL);
2508 return this->got_plt_;
2511 // Create a PLT entry for a global symbol.
2513 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2515 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2517 define_tls_base_symbol(Symbol_table*, Layout*);
2519 // Create a GOT entry for the TLS module index.
2521 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2522 Sized_relobj<32, big_endian>* object);
2524 // Get the PLT section.
2525 const Output_data_plt_arm<big_endian>*
2528 gold_assert(this->plt_ != NULL);
2532 // Get the dynamic reloc section, creating it if necessary.
2534 rel_dyn_section(Layout*);
2536 // Get the section to use for TLS_DESC relocations.
2538 rel_tls_desc_section(Layout*) const;
2540 // Return true if the symbol may need a COPY relocation.
2541 // References from an executable object to non-function symbols
2542 // defined in a dynamic object may need a COPY relocation.
2544 may_need_copy_reloc(Symbol* gsym)
2546 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2547 && gsym->may_need_copy_reloc());
2550 // Add a potential copy relocation.
2552 copy_reloc(Symbol_table* symtab, Layout* layout,
2553 Sized_relobj<32, big_endian>* object,
2554 unsigned int shndx, Output_section* output_section,
2555 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2557 this->copy_relocs_.copy_reloc(symtab, layout,
2558 symtab->get_sized_symbol<32>(sym),
2559 object, shndx, output_section, reloc,
2560 this->rel_dyn_section(layout));
2563 // Whether two EABI versions are compatible.
2565 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2567 // Merge processor-specific flags from input object and those in the ELF
2568 // header of the output.
2570 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2572 // Get the secondary compatible architecture.
2574 get_secondary_compatible_arch(const Attributes_section_data*);
2576 // Set the secondary compatible architecture.
2578 set_secondary_compatible_arch(Attributes_section_data*, int);
2581 tag_cpu_arch_combine(const char*, int, int*, int, int);
2583 // Helper to print AEABI enum tag value.
2585 aeabi_enum_name(unsigned int);
2587 // Return string value for TAG_CPU_name.
2589 tag_cpu_name_value(unsigned int);
2591 // Merge object attributes from input object and those in the output.
2593 merge_object_attributes(const char*, const Attributes_section_data*);
2595 // Helper to get an AEABI object attribute
2597 get_aeabi_object_attribute(int tag) const
2599 Attributes_section_data* pasd = this->attributes_section_data_;
2600 gold_assert(pasd != NULL);
2601 Object_attribute* attr =
2602 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2603 gold_assert(attr != NULL);
2608 // Methods to support stub-generations.
2611 // Group input sections for stub generation.
2613 group_sections(Layout*, section_size_type, bool);
2615 // Scan a relocation for stub generation.
2617 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2618 const Sized_symbol<32>*, unsigned int,
2619 const Symbol_value<32>*,
2620 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2622 // Scan a relocation section for stub.
2623 template<int sh_type>
2625 scan_reloc_section_for_stubs(
2626 const Relocate_info<32, big_endian>* relinfo,
2627 const unsigned char* prelocs,
2629 Output_section* output_section,
2630 bool needs_special_offset_handling,
2631 const unsigned char* view,
2632 elfcpp::Elf_types<32>::Elf_Addr view_address,
2635 // Fix .ARM.exidx section coverage.
2637 fix_exidx_coverage(Layout*, Arm_output_section<big_endian>*, Symbol_table*);
2639 // Functors for STL set.
2640 struct output_section_address_less_than
2643 operator()(const Output_section* s1, const Output_section* s2) const
2644 { return s1->address() < s2->address(); }
2647 // Information about this specific target which we pass to the
2648 // general Target structure.
2649 static const Target::Target_info arm_info;
2651 // The types of GOT entries needed for this platform.
2654 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2655 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2656 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2657 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2658 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2661 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2663 // Map input section to Arm_input_section.
2664 typedef Unordered_map<Section_id,
2665 Arm_input_section<big_endian>*,
2667 Arm_input_section_map;
2669 // Map output addresses to relocs for Cortex-A8 erratum.
2670 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2671 Cortex_a8_relocs_info;
2674 Arm_output_data_got<big_endian>* got_;
2676 Output_data_plt_arm<big_endian>* plt_;
2677 // The GOT PLT section.
2678 Output_data_space* got_plt_;
2679 // The dynamic reloc section.
2680 Reloc_section* rel_dyn_;
2681 // Relocs saved to avoid a COPY reloc.
2682 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2683 // Space for variables copied with a COPY reloc.
2684 Output_data_space* dynbss_;
2685 // Offset of the GOT entry for the TLS module index.
2686 unsigned int got_mod_index_offset_;
2687 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2688 bool tls_base_symbol_defined_;
2689 // Vector of Stub_tables created.
2690 Stub_table_list stub_tables_;
2692 const Stub_factory &stub_factory_;
2693 // Whether we can use BLX.
2695 // Whether we force PIC branch veneers.
2696 bool should_force_pic_veneer_;
2697 // Map for locating Arm_input_sections.
2698 Arm_input_section_map arm_input_section_map_;
2699 // Attributes section data in output.
2700 Attributes_section_data* attributes_section_data_;
2701 // Whether we want to fix code for Cortex-A8 erratum.
2702 bool fix_cortex_a8_;
2703 // Map addresses to relocs for Cortex-A8 erratum.
2704 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2707 template<bool big_endian>
2708 const Target::Target_info Target_arm<big_endian>::arm_info =
2711 big_endian, // is_big_endian
2712 elfcpp::EM_ARM, // machine_code
2713 false, // has_make_symbol
2714 false, // has_resolve
2715 false, // has_code_fill
2716 true, // is_default_stack_executable
2718 "/usr/lib/libc.so.1", // dynamic_linker
2719 0x8000, // default_text_segment_address
2720 0x1000, // abi_pagesize (overridable by -z max-page-size)
2721 0x1000, // common_pagesize (overridable by -z common-page-size)
2722 elfcpp::SHN_UNDEF, // small_common_shndx
2723 elfcpp::SHN_UNDEF, // large_common_shndx
2724 0, // small_common_section_flags
2725 0, // large_common_section_flags
2726 ".ARM.attributes", // attributes_section
2727 "aeabi" // attributes_vendor
2730 // Arm relocate functions class
2733 template<bool big_endian>
2734 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2739 STATUS_OKAY, // No error during relocation.
2740 STATUS_OVERFLOW, // Relocation oveflow.
2741 STATUS_BAD_RELOC // Relocation cannot be applied.
2745 typedef Relocate_functions<32, big_endian> Base;
2746 typedef Arm_relocate_functions<big_endian> This;
2748 // Encoding of imm16 argument for movt and movw ARM instructions
2751 // imm16 := imm4 | imm12
2753 // 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
2754 // +-------+---------------+-------+-------+-----------------------+
2755 // | | |imm4 | |imm12 |
2756 // +-------+---------------+-------+-------+-----------------------+
2758 // Extract the relocation addend from VAL based on the ARM
2759 // instruction encoding described above.
2760 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2761 extract_arm_movw_movt_addend(
2762 typename elfcpp::Swap<32, big_endian>::Valtype val)
2764 // According to the Elf ABI for ARM Architecture the immediate
2765 // field is sign-extended to form the addend.
2766 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
2769 // Insert X into VAL based on the ARM instruction encoding described
2771 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2772 insert_val_arm_movw_movt(
2773 typename elfcpp::Swap<32, big_endian>::Valtype val,
2774 typename elfcpp::Swap<32, big_endian>::Valtype x)
2778 val |= (x & 0xf000) << 4;
2782 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2785 // imm16 := imm4 | i | imm3 | imm8
2787 // 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
2788 // +---------+-+-----------+-------++-+-----+-------+---------------+
2789 // | |i| |imm4 || |imm3 | |imm8 |
2790 // +---------+-+-----------+-------++-+-----+-------+---------------+
2792 // Extract the relocation addend from VAL based on the Thumb2
2793 // instruction encoding described above.
2794 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2795 extract_thumb_movw_movt_addend(
2796 typename elfcpp::Swap<32, big_endian>::Valtype val)
2798 // According to the Elf ABI for ARM Architecture the immediate
2799 // field is sign-extended to form the addend.
2800 return utils::sign_extend<16>(((val >> 4) & 0xf000)
2801 | ((val >> 15) & 0x0800)
2802 | ((val >> 4) & 0x0700)
2806 // Insert X into VAL based on the Thumb2 instruction encoding
2808 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2809 insert_val_thumb_movw_movt(
2810 typename elfcpp::Swap<32, big_endian>::Valtype val,
2811 typename elfcpp::Swap<32, big_endian>::Valtype x)
2814 val |= (x & 0xf000) << 4;
2815 val |= (x & 0x0800) << 15;
2816 val |= (x & 0x0700) << 4;
2817 val |= (x & 0x00ff);
2821 // Calculate the smallest constant Kn for the specified residual.
2822 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2824 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
2830 // Determine the most significant bit in the residual and
2831 // align the resulting value to a 2-bit boundary.
2832 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
2834 // The desired shift is now (msb - 6), or zero, whichever
2836 return (((msb - 6) < 0) ? 0 : (msb - 6));
2839 // Calculate the final residual for the specified group index.
2840 // If the passed group index is less than zero, the method will return
2841 // the value of the specified residual without any change.
2842 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2843 static typename elfcpp::Swap<32, big_endian>::Valtype
2844 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2847 for (int n = 0; n <= group; n++)
2849 // Calculate which part of the value to mask.
2850 uint32_t shift = calc_grp_kn(residual);
2851 // Calculate the residual for the next time around.
2852 residual &= ~(residual & (0xff << shift));
2858 // Calculate the value of Gn for the specified group index.
2859 // We return it in the form of an encoded constant-and-rotation.
2860 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2861 static typename elfcpp::Swap<32, big_endian>::Valtype
2862 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2865 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
2868 for (int n = 0; n <= group; n++)
2870 // Calculate which part of the value to mask.
2871 shift = calc_grp_kn(residual);
2872 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
2873 gn = residual & (0xff << shift);
2874 // Calculate the residual for the next time around.
2877 // Return Gn in the form of an encoded constant-and-rotation.
2878 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
2882 // Handle ARM long branches.
2883 static typename This::Status
2884 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2885 unsigned char *, const Sized_symbol<32>*,
2886 const Arm_relobj<big_endian>*, unsigned int,
2887 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2889 // Handle THUMB long branches.
2890 static typename This::Status
2891 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2892 unsigned char *, const Sized_symbol<32>*,
2893 const Arm_relobj<big_endian>*, unsigned int,
2894 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2897 // Return the branch offset of a 32-bit THUMB branch.
2898 static inline int32_t
2899 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2901 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
2902 // involving the J1 and J2 bits.
2903 uint32_t s = (upper_insn & (1U << 10)) >> 10;
2904 uint32_t upper = upper_insn & 0x3ffU;
2905 uint32_t lower = lower_insn & 0x7ffU;
2906 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
2907 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
2908 uint32_t i1 = j1 ^ s ? 0 : 1;
2909 uint32_t i2 = j2 ^ s ? 0 : 1;
2911 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
2912 | (upper << 12) | (lower << 1));
2915 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
2916 // UPPER_INSN is the original upper instruction of the branch. Caller is
2917 // responsible for overflow checking and BLX offset adjustment.
2918 static inline uint16_t
2919 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
2921 uint32_t s = offset < 0 ? 1 : 0;
2922 uint32_t bits = static_cast<uint32_t>(offset);
2923 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
2926 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
2927 // LOWER_INSN is the original lower instruction of the branch. Caller is
2928 // responsible for overflow checking and BLX offset adjustment.
2929 static inline uint16_t
2930 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
2932 uint32_t s = offset < 0 ? 1 : 0;
2933 uint32_t bits = static_cast<uint32_t>(offset);
2934 return ((lower_insn & ~0x2fffU)
2935 | ((((bits >> 23) & 1) ^ !s) << 13)
2936 | ((((bits >> 22) & 1) ^ !s) << 11)
2937 | ((bits >> 1) & 0x7ffU));
2940 // Return the branch offset of a 32-bit THUMB conditional branch.
2941 static inline int32_t
2942 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2944 uint32_t s = (upper_insn & 0x0400U) >> 10;
2945 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
2946 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
2947 uint32_t lower = (lower_insn & 0x07ffU);
2948 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
2950 return utils::sign_extend<21>((upper << 12) | (lower << 1));
2953 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
2954 // instruction. UPPER_INSN is the original upper instruction of the branch.
2955 // Caller is responsible for overflow checking.
2956 static inline uint16_t
2957 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
2959 uint32_t s = offset < 0 ? 1 : 0;
2960 uint32_t bits = static_cast<uint32_t>(offset);
2961 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
2964 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
2965 // instruction. LOWER_INSN is the original lower instruction of the branch.
2966 // Caller is reponsible for overflow checking.
2967 static inline uint16_t
2968 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
2970 uint32_t bits = static_cast<uint32_t>(offset);
2971 uint32_t j2 = (bits & 0x00080000U) >> 19;
2972 uint32_t j1 = (bits & 0x00040000U) >> 18;
2973 uint32_t lo = (bits & 0x00000ffeU) >> 1;
2975 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
2978 // R_ARM_ABS8: S + A
2979 static inline typename This::Status
2980 abs8(unsigned char *view,
2981 const Sized_relobj<32, big_endian>* object,
2982 const Symbol_value<32>* psymval)
2984 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
2985 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2986 Valtype* wv = reinterpret_cast<Valtype*>(view);
2987 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
2988 Reltype addend = utils::sign_extend<8>(val);
2989 Reltype x = psymval->value(object, addend);
2990 val = utils::bit_select(val, x, 0xffU);
2991 elfcpp::Swap<8, big_endian>::writeval(wv, val);
2993 // R_ARM_ABS8 permits signed or unsigned results.
2994 int signed_x = static_cast<int32_t>(x);
2995 return ((signed_x < -128 || signed_x > 255)
2996 ? This::STATUS_OVERFLOW
2997 : This::STATUS_OKAY);
3000 // R_ARM_THM_ABS5: S + A
3001 static inline typename This::Status
3002 thm_abs5(unsigned char *view,
3003 const Sized_relobj<32, big_endian>* object,
3004 const Symbol_value<32>* psymval)
3006 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3007 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3008 Valtype* wv = reinterpret_cast<Valtype*>(view);
3009 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3010 Reltype addend = (val & 0x7e0U) >> 6;
3011 Reltype x = psymval->value(object, addend);
3012 val = utils::bit_select(val, x << 6, 0x7e0U);
3013 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3015 // R_ARM_ABS16 permits signed or unsigned results.
3016 int signed_x = static_cast<int32_t>(x);
3017 return ((signed_x < -32768 || signed_x > 65535)
3018 ? This::STATUS_OVERFLOW
3019 : This::STATUS_OKAY);
3022 // R_ARM_ABS12: S + A
3023 static inline typename This::Status
3024 abs12(unsigned char *view,
3025 const Sized_relobj<32, big_endian>* object,
3026 const Symbol_value<32>* psymval)
3028 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3029 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3030 Valtype* wv = reinterpret_cast<Valtype*>(view);
3031 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3032 Reltype addend = val & 0x0fffU;
3033 Reltype x = psymval->value(object, addend);
3034 val = utils::bit_select(val, x, 0x0fffU);
3035 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3036 return (utils::has_overflow<12>(x)
3037 ? This::STATUS_OVERFLOW
3038 : This::STATUS_OKAY);
3041 // R_ARM_ABS16: S + A
3042 static inline typename This::Status
3043 abs16(unsigned char *view,
3044 const Sized_relobj<32, big_endian>* object,
3045 const Symbol_value<32>* psymval)
3047 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3048 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3049 Valtype* wv = reinterpret_cast<Valtype*>(view);
3050 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3051 Reltype addend = utils::sign_extend<16>(val);
3052 Reltype x = psymval->value(object, addend);
3053 val = utils::bit_select(val, x, 0xffffU);
3054 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3055 return (utils::has_signed_unsigned_overflow<16>(x)
3056 ? This::STATUS_OVERFLOW
3057 : This::STATUS_OKAY);
3060 // R_ARM_ABS32: (S + A) | T
3061 static inline typename This::Status
3062 abs32(unsigned char *view,
3063 const Sized_relobj<32, big_endian>* object,
3064 const Symbol_value<32>* psymval,
3065 Arm_address thumb_bit)
3067 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3068 Valtype* wv = reinterpret_cast<Valtype*>(view);
3069 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3070 Valtype x = psymval->value(object, addend) | thumb_bit;
3071 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3072 return This::STATUS_OKAY;
3075 // R_ARM_REL32: (S + A) | T - P
3076 static inline typename This::Status
3077 rel32(unsigned char *view,
3078 const Sized_relobj<32, big_endian>* object,
3079 const Symbol_value<32>* psymval,
3080 Arm_address address,
3081 Arm_address thumb_bit)
3083 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3084 Valtype* wv = reinterpret_cast<Valtype*>(view);
3085 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3086 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3087 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3088 return This::STATUS_OKAY;
3091 // R_ARM_THM_JUMP24: (S + A) | T - P
3092 static typename This::Status
3093 thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object,
3094 const Symbol_value<32>* psymval, Arm_address address,
3095 Arm_address thumb_bit);
3097 // R_ARM_THM_JUMP6: S + A – P
3098 static inline typename This::Status
3099 thm_jump6(unsigned char *view,
3100 const Sized_relobj<32, big_endian>* object,
3101 const Symbol_value<32>* psymval,
3102 Arm_address address)
3104 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3105 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3106 Valtype* wv = reinterpret_cast<Valtype*>(view);
3107 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3108 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3109 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3110 Reltype x = (psymval->value(object, addend) - address);
3111 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3112 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3113 // CZB does only forward jumps.
3114 return ((x > 0x007e)
3115 ? This::STATUS_OVERFLOW
3116 : This::STATUS_OKAY);
3119 // R_ARM_THM_JUMP8: S + A – P
3120 static inline typename This::Status
3121 thm_jump8(unsigned char *view,
3122 const Sized_relobj<32, big_endian>* object,
3123 const Symbol_value<32>* psymval,
3124 Arm_address address)
3126 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3127 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3128 Valtype* wv = reinterpret_cast<Valtype*>(view);
3129 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3130 Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
3131 Reltype x = (psymval->value(object, addend) - address);
3132 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
3133 return (utils::has_overflow<8>(x)
3134 ? This::STATUS_OVERFLOW
3135 : This::STATUS_OKAY);
3138 // R_ARM_THM_JUMP11: S + A – P
3139 static inline typename This::Status
3140 thm_jump11(unsigned char *view,
3141 const Sized_relobj<32, big_endian>* object,
3142 const Symbol_value<32>* psymval,
3143 Arm_address address)
3145 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3146 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3147 Valtype* wv = reinterpret_cast<Valtype*>(view);
3148 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3149 Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
3150 Reltype x = (psymval->value(object, addend) - address);
3151 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
3152 return (utils::has_overflow<11>(x)
3153 ? This::STATUS_OVERFLOW
3154 : This::STATUS_OKAY);
3157 // R_ARM_BASE_PREL: B(S) + A - P
3158 static inline typename This::Status
3159 base_prel(unsigned char* view,
3161 Arm_address address)
3163 Base::rel32(view, origin - address);
3167 // R_ARM_BASE_ABS: B(S) + A
3168 static inline typename This::Status
3169 base_abs(unsigned char* view,
3172 Base::rel32(view, origin);
3176 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3177 static inline typename This::Status
3178 got_brel(unsigned char* view,
3179 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3181 Base::rel32(view, got_offset);
3182 return This::STATUS_OKAY;
3185 // R_ARM_GOT_PREL: GOT(S) + A - P
3186 static inline typename This::Status
3187 got_prel(unsigned char *view,
3188 Arm_address got_entry,
3189 Arm_address address)
3191 Base::rel32(view, got_entry - address);
3192 return This::STATUS_OKAY;
3195 // R_ARM_PREL: (S + A) | T - P
3196 static inline typename This::Status
3197 prel31(unsigned char *view,
3198 const Sized_relobj<32, big_endian>* object,
3199 const Symbol_value<32>* psymval,
3200 Arm_address address,
3201 Arm_address thumb_bit)
3203 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3204 Valtype* wv = reinterpret_cast<Valtype*>(view);
3205 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3206 Valtype addend = utils::sign_extend<31>(val);
3207 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3208 val = utils::bit_select(val, x, 0x7fffffffU);
3209 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3210 return (utils::has_overflow<31>(x) ?
3211 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3214 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3215 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3216 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3217 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3218 static inline typename This::Status
3219 movw(unsigned char* view,
3220 const Sized_relobj<32, big_endian>* object,
3221 const Symbol_value<32>* psymval,
3222 Arm_address relative_address_base,
3223 Arm_address thumb_bit,
3224 bool check_overflow)
3226 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3227 Valtype* wv = reinterpret_cast<Valtype*>(view);
3228 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3229 Valtype addend = This::extract_arm_movw_movt_addend(val);
3230 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3231 - relative_address_base);
3232 val = This::insert_val_arm_movw_movt(val, x);
3233 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3234 return ((check_overflow && utils::has_overflow<16>(x))
3235 ? This::STATUS_OVERFLOW
3236 : This::STATUS_OKAY);
3239 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3240 // R_ARM_MOVT_PREL: S + A - P
3241 // R_ARM_MOVT_BREL: S + A - B(S)
3242 static inline typename This::Status
3243 movt(unsigned char* view,
3244 const Sized_relobj<32, big_endian>* object,
3245 const Symbol_value<32>* psymval,
3246 Arm_address relative_address_base)
3248 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3249 Valtype* wv = reinterpret_cast<Valtype*>(view);
3250 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3251 Valtype addend = This::extract_arm_movw_movt_addend(val);
3252 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3253 val = This::insert_val_arm_movw_movt(val, x);
3254 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3255 // FIXME: IHI0044D says that we should check for overflow.
3256 return This::STATUS_OKAY;
3259 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3260 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3261 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3262 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3263 static inline typename This::Status
3264 thm_movw(unsigned char *view,
3265 const Sized_relobj<32, big_endian>* object,
3266 const Symbol_value<32>* psymval,
3267 Arm_address relative_address_base,
3268 Arm_address thumb_bit,
3269 bool check_overflow)
3271 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3272 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3273 Valtype* wv = reinterpret_cast<Valtype*>(view);
3274 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3275 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3276 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3278 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3279 val = This::insert_val_thumb_movw_movt(val, x);
3280 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3281 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3282 return ((check_overflow && utils::has_overflow<16>(x))
3283 ? This::STATUS_OVERFLOW
3284 : This::STATUS_OKAY);
3287 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3288 // R_ARM_THM_MOVT_PREL: S + A - P
3289 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3290 static inline typename This::Status
3291 thm_movt(unsigned char* view,
3292 const Sized_relobj<32, big_endian>* object,
3293 const Symbol_value<32>* psymval,
3294 Arm_address relative_address_base)
3296 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3297 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3298 Valtype* wv = reinterpret_cast<Valtype*>(view);
3299 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3300 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3301 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3302 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3303 val = This::insert_val_thumb_movw_movt(val, x);
3304 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3305 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3306 return This::STATUS_OKAY;
3309 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3310 static inline typename This::Status
3311 thm_alu11(unsigned char* view,
3312 const Sized_relobj<32, big_endian>* object,
3313 const Symbol_value<32>* psymval,
3314 Arm_address address,
3315 Arm_address thumb_bit)
3317 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3318 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3319 Valtype* wv = reinterpret_cast<Valtype*>(view);
3320 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3321 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3323 // 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
3324 // -----------------------------------------------------------------------
3325 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3326 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3327 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3328 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3329 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3330 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3332 // Determine a sign for the addend.
3333 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3334 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3335 // Thumb2 addend encoding:
3336 // imm12 := i | imm3 | imm8
3337 int32_t addend = (insn & 0xff)
3338 | ((insn & 0x00007000) >> 4)
3339 | ((insn & 0x04000000) >> 15);
3340 // Apply a sign to the added.
3343 int32_t x = (psymval->value(object, addend) | thumb_bit)
3344 - (address & 0xfffffffc);
3345 Reltype val = abs(x);
3346 // Mask out the value and a distinct part of the ADD/SUB opcode
3347 // (bits 7:5 of opword).
3348 insn = (insn & 0xfb0f8f00)
3350 | ((val & 0x700) << 4)
3351 | ((val & 0x800) << 15);
3352 // Set the opcode according to whether the value to go in the
3353 // place is negative.
3357 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3358 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3359 return ((val > 0xfff) ?
3360 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3363 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3364 static inline typename This::Status
3365 thm_pc8(unsigned char* view,
3366 const Sized_relobj<32, big_endian>* object,
3367 const Symbol_value<32>* psymval,
3368 Arm_address address)
3370 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3371 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3372 Valtype* wv = reinterpret_cast<Valtype*>(view);
3373 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3374 Reltype addend = ((insn & 0x00ff) << 2);
3375 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3376 Reltype val = abs(x);
3377 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3379 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3380 return ((val > 0x03fc)
3381 ? This::STATUS_OVERFLOW
3382 : This::STATUS_OKAY);
3385 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3386 static inline typename This::Status
3387 thm_pc12(unsigned char* view,
3388 const Sized_relobj<32, big_endian>* object,
3389 const Symbol_value<32>* psymval,
3390 Arm_address address)
3392 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3393 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3394 Valtype* wv = reinterpret_cast<Valtype*>(view);
3395 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3396 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3397 // Determine a sign for the addend (positive if the U bit is 1).
3398 const int sign = (insn & 0x00800000) ? 1 : -1;
3399 int32_t addend = (insn & 0xfff);
3400 // Apply a sign to the added.
3403 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3404 Reltype val = abs(x);
3405 // Mask out and apply the value and the U bit.
3406 insn = (insn & 0xff7ff000) | (val & 0xfff);
3407 // Set the U bit according to whether the value to go in the
3408 // place is positive.
3412 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3413 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3414 return ((val > 0xfff) ?
3415 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3419 static inline typename This::Status
3420 v4bx(const Relocate_info<32, big_endian>* relinfo,
3421 unsigned char *view,
3422 const Arm_relobj<big_endian>* object,
3423 const Arm_address address,
3424 const bool is_interworking)
3427 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3428 Valtype* wv = reinterpret_cast<Valtype*>(view);
3429 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3431 // Ensure that we have a BX instruction.
3432 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3433 const uint32_t reg = (val & 0xf);
3434 if (is_interworking && reg != 0xf)
3436 Stub_table<big_endian>* stub_table =
3437 object->stub_table(relinfo->data_shndx);
3438 gold_assert(stub_table != NULL);
3440 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3441 gold_assert(stub != NULL);
3443 int32_t veneer_address =
3444 stub_table->address() + stub->offset() - 8 - address;
3445 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3446 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3447 // Replace with a branch to veneer (B <addr>)
3448 val = (val & 0xf0000000) | 0x0a000000
3449 | ((veneer_address >> 2) & 0x00ffffff);
3453 // Preserve Rm (lowest four bits) and the condition code
3454 // (highest four bits). Other bits encode MOV PC,Rm.
3455 val = (val & 0xf000000f) | 0x01a0f000;
3457 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3458 return This::STATUS_OKAY;
3461 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3462 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3463 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3464 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3465 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3466 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3467 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3468 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3469 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3470 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3471 static inline typename This::Status
3472 arm_grp_alu(unsigned char* view,
3473 const Sized_relobj<32, big_endian>* object,
3474 const Symbol_value<32>* psymval,
3476 Arm_address address,
3477 Arm_address thumb_bit,
3478 bool check_overflow)
3480 gold_assert(group >= 0 && group < 3);
3481 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3482 Valtype* wv = reinterpret_cast<Valtype*>(view);
3483 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3485 // ALU group relocations are allowed only for the ADD/SUB instructions.
3486 // (0x00800000 - ADD, 0x00400000 - SUB)
3487 const Valtype opcode = insn & 0x01e00000;
3488 if (opcode != 0x00800000 && opcode != 0x00400000)
3489 return This::STATUS_BAD_RELOC;
3491 // Determine a sign for the addend.
3492 const int sign = (opcode == 0x00800000) ? 1 : -1;
3493 // shifter = rotate_imm * 2
3494 const uint32_t shifter = (insn & 0xf00) >> 7;
3495 // Initial addend value.
3496 int32_t addend = insn & 0xff;
3497 // Rotate addend right by shifter.
3498 addend = (addend >> shifter) | (addend << (32 - shifter));
3499 // Apply a sign to the added.
3502 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3503 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3504 // Check for overflow if required
3506 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3507 return This::STATUS_OVERFLOW;
3509 // Mask out the value and the ADD/SUB part of the opcode; take care
3510 // not to destroy the S bit.
3512 // Set the opcode according to whether the value to go in the
3513 // place is negative.
3514 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3515 // Encode the offset (encoded Gn).
3518 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3519 return This::STATUS_OKAY;
3522 // R_ARM_LDR_PC_G0: S + A - P
3523 // R_ARM_LDR_PC_G1: S + A - P
3524 // R_ARM_LDR_PC_G2: S + A - P
3525 // R_ARM_LDR_SB_G0: S + A - B(S)
3526 // R_ARM_LDR_SB_G1: S + A - B(S)
3527 // R_ARM_LDR_SB_G2: S + A - B(S)
3528 static inline typename This::Status
3529 arm_grp_ldr(unsigned char* view,
3530 const Sized_relobj<32, big_endian>* object,
3531 const Symbol_value<32>* psymval,
3533 Arm_address address)
3535 gold_assert(group >= 0 && group < 3);
3536 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3537 Valtype* wv = reinterpret_cast<Valtype*>(view);
3538 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3540 const int sign = (insn & 0x00800000) ? 1 : -1;
3541 int32_t addend = (insn & 0xfff) * sign;
3542 int32_t x = (psymval->value(object, addend) - address);
3543 // Calculate the relevant G(n-1) value to obtain this stage residual.
3545 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3546 if (residual >= 0x1000)
3547 return This::STATUS_OVERFLOW;
3549 // Mask out the value and U bit.
3551 // Set the U bit for non-negative values.
3556 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3557 return This::STATUS_OKAY;
3560 // R_ARM_LDRS_PC_G0: S + A - P
3561 // R_ARM_LDRS_PC_G1: S + A - P
3562 // R_ARM_LDRS_PC_G2: S + A - P
3563 // R_ARM_LDRS_SB_G0: S + A - B(S)
3564 // R_ARM_LDRS_SB_G1: S + A - B(S)
3565 // R_ARM_LDRS_SB_G2: S + A - B(S)
3566 static inline typename This::Status
3567 arm_grp_ldrs(unsigned char* view,
3568 const Sized_relobj<32, big_endian>* object,
3569 const Symbol_value<32>* psymval,
3571 Arm_address address)
3573 gold_assert(group >= 0 && group < 3);
3574 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3575 Valtype* wv = reinterpret_cast<Valtype*>(view);
3576 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3578 const int sign = (insn & 0x00800000) ? 1 : -1;
3579 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3580 int32_t x = (psymval->value(object, addend) - address);
3581 // Calculate the relevant G(n-1) value to obtain this stage residual.
3583 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3584 if (residual >= 0x100)
3585 return This::STATUS_OVERFLOW;
3587 // Mask out the value and U bit.
3589 // Set the U bit for non-negative values.
3592 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3594 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3595 return This::STATUS_OKAY;
3598 // R_ARM_LDC_PC_G0: S + A - P
3599 // R_ARM_LDC_PC_G1: S + A - P
3600 // R_ARM_LDC_PC_G2: S + A - P
3601 // R_ARM_LDC_SB_G0: S + A - B(S)
3602 // R_ARM_LDC_SB_G1: S + A - B(S)
3603 // R_ARM_LDC_SB_G2: S + A - B(S)
3604 static inline typename This::Status
3605 arm_grp_ldc(unsigned char* view,
3606 const Sized_relobj<32, big_endian>* object,
3607 const Symbol_value<32>* psymval,
3609 Arm_address address)
3611 gold_assert(group >= 0 && group < 3);
3612 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3613 Valtype* wv = reinterpret_cast<Valtype*>(view);
3614 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3616 const int sign = (insn & 0x00800000) ? 1 : -1;
3617 int32_t addend = ((insn & 0xff) << 2) * sign;
3618 int32_t x = (psymval->value(object, addend) - address);
3619 // Calculate the relevant G(n-1) value to obtain this stage residual.
3621 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3622 if ((residual & 0x3) != 0 || residual >= 0x400)
3623 return This::STATUS_OVERFLOW;
3625 // Mask out the value and U bit.
3627 // Set the U bit for non-negative values.
3630 insn |= (residual >> 2);
3632 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3633 return This::STATUS_OKAY;
3637 // Relocate ARM long branches. This handles relocation types
3638 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3639 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3640 // undefined and we do not use PLT in this relocation. In such a case,
3641 // the branch is converted into an NOP.
3643 template<bool big_endian>
3644 typename Arm_relocate_functions<big_endian>::Status
3645 Arm_relocate_functions<big_endian>::arm_branch_common(
3646 unsigned int r_type,
3647 const Relocate_info<32, big_endian>* relinfo,
3648 unsigned char *view,
3649 const Sized_symbol<32>* gsym,
3650 const Arm_relobj<big_endian>* object,
3652 const Symbol_value<32>* psymval,
3653 Arm_address address,
3654 Arm_address thumb_bit,
3655 bool is_weakly_undefined_without_plt)
3657 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3658 Valtype* wv = reinterpret_cast<Valtype*>(view);
3659 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3661 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3662 && ((val & 0x0f000000UL) == 0x0a000000UL);
3663 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3664 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3665 && ((val & 0x0f000000UL) == 0x0b000000UL);
3666 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3667 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3669 // Check that the instruction is valid.
3670 if (r_type == elfcpp::R_ARM_CALL)
3672 if (!insn_is_uncond_bl && !insn_is_blx)
3673 return This::STATUS_BAD_RELOC;
3675 else if (r_type == elfcpp::R_ARM_JUMP24)
3677 if (!insn_is_b && !insn_is_cond_bl)
3678 return This::STATUS_BAD_RELOC;
3680 else if (r_type == elfcpp::R_ARM_PLT32)
3682 if (!insn_is_any_branch)
3683 return This::STATUS_BAD_RELOC;
3685 else if (r_type == elfcpp::R_ARM_XPC25)
3687 // FIXME: AAELF document IH0044C does not say much about it other
3688 // than it being obsolete.
3689 if (!insn_is_any_branch)
3690 return This::STATUS_BAD_RELOC;
3695 // A branch to an undefined weak symbol is turned into a jump to
3696 // the next instruction unless a PLT entry will be created.
3697 // Do the same for local undefined symbols.
3698 // The jump to the next instruction is optimized as a NOP depending
3699 // on the architecture.
3700 const Target_arm<big_endian>* arm_target =
3701 Target_arm<big_endian>::default_target();
3702 if (is_weakly_undefined_without_plt)
3704 Valtype cond = val & 0xf0000000U;
3705 if (arm_target->may_use_arm_nop())
3706 val = cond | 0x0320f000;
3708 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3709 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3710 return This::STATUS_OKAY;
3713 Valtype addend = utils::sign_extend<26>(val << 2);
3714 Valtype branch_target = psymval->value(object, addend);
3715 int32_t branch_offset = branch_target - address;
3717 // We need a stub if the branch offset is too large or if we need
3719 bool may_use_blx = arm_target->may_use_blx();
3720 Reloc_stub* stub = NULL;
3721 if (utils::has_overflow<26>(branch_offset)
3722 || ((thumb_bit != 0) && !(may_use_blx && r_type == elfcpp::R_ARM_CALL)))
3724 Valtype unadjusted_branch_target = psymval->value(object, 0);
3726 Stub_type stub_type =
3727 Reloc_stub::stub_type_for_reloc(r_type, address,
3728 unadjusted_branch_target,
3730 if (stub_type != arm_stub_none)
3732 Stub_table<big_endian>* stub_table =
3733 object->stub_table(relinfo->data_shndx);
3734 gold_assert(stub_table != NULL);
3736 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3737 stub = stub_table->find_reloc_stub(stub_key);
3738 gold_assert(stub != NULL);
3739 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3740 branch_target = stub_table->address() + stub->offset() + addend;
3741 branch_offset = branch_target - address;
3742 gold_assert(!utils::has_overflow<26>(branch_offset));
3746 // At this point, if we still need to switch mode, the instruction
3747 // must either be a BLX or a BL that can be converted to a BLX.
3751 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3752 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3755 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
3756 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3757 return (utils::has_overflow<26>(branch_offset)
3758 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
3761 // Relocate THUMB long branches. This handles relocation types
3762 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3763 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3764 // undefined and we do not use PLT in this relocation. In such a case,
3765 // the branch is converted into an NOP.
3767 template<bool big_endian>
3768 typename Arm_relocate_functions<big_endian>::Status
3769 Arm_relocate_functions<big_endian>::thumb_branch_common(
3770 unsigned int r_type,
3771 const Relocate_info<32, big_endian>* relinfo,
3772 unsigned char *view,
3773 const Sized_symbol<32>* gsym,
3774 const Arm_relobj<big_endian>* object,
3776 const Symbol_value<32>* psymval,
3777 Arm_address address,
3778 Arm_address thumb_bit,
3779 bool is_weakly_undefined_without_plt)
3781 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3782 Valtype* wv = reinterpret_cast<Valtype*>(view);
3783 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3784 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3786 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3788 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
3789 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
3791 // Check that the instruction is valid.
3792 if (r_type == elfcpp::R_ARM_THM_CALL)
3794 if (!is_bl_insn && !is_blx_insn)
3795 return This::STATUS_BAD_RELOC;
3797 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
3799 // This cannot be a BLX.
3801 return This::STATUS_BAD_RELOC;
3803 else if (r_type == elfcpp::R_ARM_THM_XPC22)
3805 // Check for Thumb to Thumb call.
3807 return This::STATUS_BAD_RELOC;
3810 gold_warning(_("%s: Thumb BLX instruction targets "
3811 "thumb function '%s'."),
3812 object->name().c_str(),
3813 (gsym ? gsym->name() : "(local)"));
3814 // Convert BLX to BL.
3815 lower_insn |= 0x1000U;
3821 // A branch to an undefined weak symbol is turned into a jump to
3822 // the next instruction unless a PLT entry will be created.
3823 // The jump to the next instruction is optimized as a NOP.W for
3824 // Thumb-2 enabled architectures.
3825 const Target_arm<big_endian>* arm_target =
3826 Target_arm<big_endian>::default_target();
3827 if (is_weakly_undefined_without_plt)
3829 if (arm_target->may_use_thumb2_nop())
3831 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
3832 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
3836 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
3837 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
3839 return This::STATUS_OKAY;
3842 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
3843 Arm_address branch_target = psymval->value(object, addend);
3845 // For BLX, bit 1 of target address comes from bit 1 of base address.
3846 bool may_use_blx = arm_target->may_use_blx();
3847 if (thumb_bit == 0 && may_use_blx)
3848 branch_target = utils::bit_select(branch_target, address, 0x2);
3850 int32_t branch_offset = branch_target - address;
3852 // We need a stub if the branch offset is too large or if we need
3854 bool thumb2 = arm_target->using_thumb2();
3855 if ((!thumb2 && utils::has_overflow<23>(branch_offset))
3856 || (thumb2 && utils::has_overflow<25>(branch_offset))
3857 || ((thumb_bit == 0)
3858 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
3859 || r_type == elfcpp::R_ARM_THM_JUMP24)))
3861 Arm_address unadjusted_branch_target = psymval->value(object, 0);
3863 Stub_type stub_type =
3864 Reloc_stub::stub_type_for_reloc(r_type, address,
3865 unadjusted_branch_target,
3868 if (stub_type != arm_stub_none)
3870 Stub_table<big_endian>* stub_table =
3871 object->stub_table(relinfo->data_shndx);
3872 gold_assert(stub_table != NULL);
3874 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3875 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
3876 gold_assert(stub != NULL);
3877 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3878 branch_target = stub_table->address() + stub->offset() + addend;
3879 if (thumb_bit == 0 && may_use_blx)
3880 branch_target = utils::bit_select(branch_target, address, 0x2);
3881 branch_offset = branch_target - address;
3885 // At this point, if we still need to switch mode, the instruction
3886 // must either be a BLX or a BL that can be converted to a BLX.
3889 gold_assert(may_use_blx
3890 && (r_type == elfcpp::R_ARM_THM_CALL
3891 || r_type == elfcpp::R_ARM_THM_XPC22));
3892 // Make sure this is a BLX.
3893 lower_insn &= ~0x1000U;
3897 // Make sure this is a BL.
3898 lower_insn |= 0x1000U;
3901 // For a BLX instruction, make sure that the relocation is rounded up
3902 // to a word boundary. This follows the semantics of the instruction
3903 // which specifies that bit 1 of the target address will come from bit
3904 // 1 of the base address.
3905 if ((lower_insn & 0x5000U) == 0x4000U)
3906 gold_assert((branch_offset & 3) == 0);
3908 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
3909 // We use the Thumb-2 encoding, which is safe even if dealing with
3910 // a Thumb-1 instruction by virtue of our overflow check above. */
3911 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
3912 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
3914 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3915 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3917 gold_assert(!utils::has_overflow<25>(branch_offset));
3920 ? utils::has_overflow<25>(branch_offset)
3921 : utils::has_overflow<23>(branch_offset))
3922 ? This::STATUS_OVERFLOW
3923 : This::STATUS_OKAY);
3926 // Relocate THUMB-2 long conditional branches.
3927 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3928 // undefined and we do not use PLT in this relocation. In such a case,
3929 // the branch is converted into an NOP.
3931 template<bool big_endian>
3932 typename Arm_relocate_functions<big_endian>::Status
3933 Arm_relocate_functions<big_endian>::thm_jump19(
3934 unsigned char *view,
3935 const Arm_relobj<big_endian>* object,
3936 const Symbol_value<32>* psymval,
3937 Arm_address address,
3938 Arm_address thumb_bit)
3940 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3941 Valtype* wv = reinterpret_cast<Valtype*>(view);
3942 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3943 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3944 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
3946 Arm_address branch_target = psymval->value(object, addend);
3947 int32_t branch_offset = branch_target - address;
3949 // ??? Should handle interworking? GCC might someday try to
3950 // use this for tail calls.
3951 // FIXME: We do support thumb entry to PLT yet.
3954 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
3955 return This::STATUS_BAD_RELOC;
3958 // Put RELOCATION back into the insn.
3959 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
3960 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
3962 // Put the relocated value back in the object file:
3963 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3964 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3966 return (utils::has_overflow<21>(branch_offset)
3967 ? This::STATUS_OVERFLOW
3968 : This::STATUS_OKAY);
3971 // Get the GOT section, creating it if necessary.
3973 template<bool big_endian>
3974 Arm_output_data_got<big_endian>*
3975 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
3977 if (this->got_ == NULL)
3979 gold_assert(symtab != NULL && layout != NULL);
3981 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
3984 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3986 | elfcpp::SHF_WRITE),
3987 this->got_, false, false, false,
3989 // The old GNU linker creates a .got.plt section. We just
3990 // create another set of data in the .got section. Note that we
3991 // always create a PLT if we create a GOT, although the PLT
3993 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
3994 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3996 | elfcpp::SHF_WRITE),
3997 this->got_plt_, false, false,
4000 // The first three entries are reserved.
4001 this->got_plt_->set_current_data_size(3 * 4);
4003 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
4004 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
4005 Symbol_table::PREDEFINED,
4007 0, 0, elfcpp::STT_OBJECT,
4009 elfcpp::STV_HIDDEN, 0,
4015 // Get the dynamic reloc section, creating it if necessary.
4017 template<bool big_endian>
4018 typename Target_arm<big_endian>::Reloc_section*
4019 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
4021 if (this->rel_dyn_ == NULL)
4023 gold_assert(layout != NULL);
4024 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
4025 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
4026 elfcpp::SHF_ALLOC, this->rel_dyn_, true,
4027 false, false, false);
4029 return this->rel_dyn_;
4032 // Insn_template methods.
4034 // Return byte size of an instruction template.
4037 Insn_template::size() const
4039 switch (this->type())
4042 case THUMB16_SPECIAL_TYPE:
4053 // Return alignment of an instruction template.
4056 Insn_template::alignment() const
4058 switch (this->type())
4061 case THUMB16_SPECIAL_TYPE:
4072 // Stub_template methods.
4074 Stub_template::Stub_template(
4075 Stub_type type, const Insn_template* insns,
4077 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4078 entry_in_thumb_mode_(false), relocs_()
4082 // Compute byte size and alignment of stub template.
4083 for (size_t i = 0; i < insn_count; i++)
4085 unsigned insn_alignment = insns[i].alignment();
4086 size_t insn_size = insns[i].size();
4087 gold_assert((offset & (insn_alignment - 1)) == 0);
4088 this->alignment_ = std::max(this->alignment_, insn_alignment);
4089 switch (insns[i].type())
4091 case Insn_template::THUMB16_TYPE:
4092 case Insn_template::THUMB16_SPECIAL_TYPE:
4094 this->entry_in_thumb_mode_ = true;
4097 case Insn_template::THUMB32_TYPE:
4098 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4099 this->relocs_.push_back(Reloc(i, offset));
4101 this->entry_in_thumb_mode_ = true;
4104 case Insn_template::ARM_TYPE:
4105 // Handle cases where the target is encoded within the
4107 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4108 this->relocs_.push_back(Reloc(i, offset));
4111 case Insn_template::DATA_TYPE:
4112 // Entry point cannot be data.
4113 gold_assert(i != 0);
4114 this->relocs_.push_back(Reloc(i, offset));
4120 offset += insn_size;
4122 this->size_ = offset;
4127 // Template to implement do_write for a specific target endianity.
4129 template<bool big_endian>
4131 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4133 const Stub_template* stub_template = this->stub_template();
4134 const Insn_template* insns = stub_template->insns();
4136 // FIXME: We do not handle BE8 encoding yet.
4137 unsigned char* pov = view;
4138 for (size_t i = 0; i < stub_template->insn_count(); i++)
4140 switch (insns[i].type())
4142 case Insn_template::THUMB16_TYPE:
4143 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4145 case Insn_template::THUMB16_SPECIAL_TYPE:
4146 elfcpp::Swap<16, big_endian>::writeval(
4148 this->thumb16_special(i));
4150 case Insn_template::THUMB32_TYPE:
4152 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4153 uint32_t lo = insns[i].data() & 0xffff;
4154 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4155 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4158 case Insn_template::ARM_TYPE:
4159 case Insn_template::DATA_TYPE:
4160 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4165 pov += insns[i].size();
4167 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4170 // Reloc_stub::Key methods.
4172 // Dump a Key as a string for debugging.
4175 Reloc_stub::Key::name() const
4177 if (this->r_sym_ == invalid_index)
4179 // Global symbol key name
4180 // <stub-type>:<symbol name>:<addend>.
4181 const std::string sym_name = this->u_.symbol->name();
4182 // We need to print two hex number and two colons. So just add 100 bytes
4183 // to the symbol name size.
4184 size_t len = sym_name.size() + 100;
4185 char* buffer = new char[len];
4186 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4187 sym_name.c_str(), this->addend_);
4188 gold_assert(c > 0 && c < static_cast<int>(len));
4190 return std::string(buffer);
4194 // local symbol key name
4195 // <stub-type>:<object>:<r_sym>:<addend>.
4196 const size_t len = 200;
4198 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4199 this->u_.relobj, this->r_sym_, this->addend_);
4200 gold_assert(c > 0 && c < static_cast<int>(len));
4201 return std::string(buffer);
4205 // Reloc_stub methods.
4207 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4208 // LOCATION to DESTINATION.
4209 // This code is based on the arm_type_of_stub function in
4210 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
4214 Reloc_stub::stub_type_for_reloc(
4215 unsigned int r_type,
4216 Arm_address location,
4217 Arm_address destination,
4218 bool target_is_thumb)
4220 Stub_type stub_type = arm_stub_none;
4222 // This is a bit ugly but we want to avoid using a templated class for
4223 // big and little endianities.
4225 bool should_force_pic_veneer;
4228 if (parameters->target().is_big_endian())
4230 const Target_arm<true>* big_endian_target =
4231 Target_arm<true>::default_target();
4232 may_use_blx = big_endian_target->may_use_blx();
4233 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4234 thumb2 = big_endian_target->using_thumb2();
4235 thumb_only = big_endian_target->using_thumb_only();
4239 const Target_arm<false>* little_endian_target =
4240 Target_arm<false>::default_target();
4241 may_use_blx = little_endian_target->may_use_blx();
4242 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4243 thumb2 = little_endian_target->using_thumb2();
4244 thumb_only = little_endian_target->using_thumb_only();
4247 int64_t branch_offset;
4248 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4250 // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
4251 // base address (instruction address + 4).
4252 if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
4253 destination = utils::bit_select(destination, location, 0x2);
4254 branch_offset = static_cast<int64_t>(destination) - location;
4256 // Handle cases where:
4257 // - this call goes too far (different Thumb/Thumb2 max
4259 // - it's a Thumb->Arm call and blx is not available, or it's a
4260 // Thumb->Arm branch (not bl). A stub is needed in this case.
4262 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4263 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4265 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4266 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4267 || ((!target_is_thumb)
4268 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4269 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4271 if (target_is_thumb)
4276 stub_type = (parameters->options().shared()
4277 || should_force_pic_veneer)
4280 && (r_type == elfcpp::R_ARM_THM_CALL))
4281 // V5T and above. Stub starts with ARM code, so
4282 // we must be able to switch mode before
4283 // reaching it, which is only possible for 'bl'
4284 // (ie R_ARM_THM_CALL relocation).
4285 ? arm_stub_long_branch_any_thumb_pic
4286 // On V4T, use Thumb code only.
4287 : arm_stub_long_branch_v4t_thumb_thumb_pic)
4291 && (r_type == elfcpp::R_ARM_THM_CALL))
4292 ? arm_stub_long_branch_any_any // V5T and above.
4293 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
4297 stub_type = (parameters->options().shared()
4298 || should_force_pic_veneer)
4299 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4300 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4307 // FIXME: We should check that the input section is from an
4308 // object that has interwork enabled.
4310 stub_type = (parameters->options().shared()
4311 || should_force_pic_veneer)
4314 && (r_type == elfcpp::R_ARM_THM_CALL))
4315 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4316 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4320 && (r_type == elfcpp::R_ARM_THM_CALL))
4321 ? arm_stub_long_branch_any_any // V5T and above.
4322 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4324 // Handle v4t short branches.
4325 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4326 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4327 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4328 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4332 else if (r_type == elfcpp::R_ARM_CALL
4333 || r_type == elfcpp::R_ARM_JUMP24
4334 || r_type == elfcpp::R_ARM_PLT32)
4336 branch_offset = static_cast<int64_t>(destination) - location;
4337 if (target_is_thumb)
4341 // FIXME: We should check that the input section is from an
4342 // object that has interwork enabled.
4344 // We have an extra 2-bytes reach because of
4345 // the mode change (bit 24 (H) of BLX encoding).
4346 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4347 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4348 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4349 || (r_type == elfcpp::R_ARM_JUMP24)
4350 || (r_type == elfcpp::R_ARM_PLT32))
4352 stub_type = (parameters->options().shared()
4353 || should_force_pic_veneer)
4356 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4357 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4361 ? arm_stub_long_branch_any_any // V5T and above.
4362 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4368 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4369 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4371 stub_type = (parameters->options().shared()
4372 || should_force_pic_veneer)
4373 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4374 : arm_stub_long_branch_any_any; /// non-PIC.
4382 // Cortex_a8_stub methods.
4384 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4385 // I is the position of the instruction template in the stub template.
4388 Cortex_a8_stub::do_thumb16_special(size_t i)
4390 // The only use of this is to copy condition code from a conditional
4391 // branch being worked around to the corresponding conditional branch in
4393 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4395 uint16_t data = this->stub_template()->insns()[i].data();
4396 gold_assert((data & 0xff00U) == 0xd000U);
4397 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4401 // Stub_factory methods.
4403 Stub_factory::Stub_factory()
4405 // The instruction template sequences are declared as static
4406 // objects and initialized first time the constructor runs.
4408 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4409 // to reach the stub if necessary.
4410 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4412 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4413 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4414 // dcd R_ARM_ABS32(X)
4417 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4419 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4421 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4422 Insn_template::arm_insn(0xe12fff1c), // bx ip
4423 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4424 // dcd R_ARM_ABS32(X)
4427 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4428 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4430 Insn_template::thumb16_insn(0xb401), // push {r0}
4431 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4432 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4433 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4434 Insn_template::thumb16_insn(0x4760), // bx ip
4435 Insn_template::thumb16_insn(0xbf00), // nop
4436 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4437 // dcd R_ARM_ABS32(X)
4440 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4442 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4444 Insn_template::thumb16_insn(0x4778), // bx pc
4445 Insn_template::thumb16_insn(0x46c0), // nop
4446 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4447 Insn_template::arm_insn(0xe12fff1c), // bx ip
4448 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4449 // dcd R_ARM_ABS32(X)
4452 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4454 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4456 Insn_template::thumb16_insn(0x4778), // bx pc
4457 Insn_template::thumb16_insn(0x46c0), // nop
4458 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4459 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4460 // dcd R_ARM_ABS32(X)
4463 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4464 // one, when the destination is close enough.
4465 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4467 Insn_template::thumb16_insn(0x4778), // bx pc
4468 Insn_template::thumb16_insn(0x46c0), // nop
4469 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4472 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4473 // blx to reach the stub if necessary.
4474 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4476 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4477 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4478 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4479 // dcd R_ARM_REL32(X-4)
4482 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4483 // blx to reach the stub if necessary. We can not add into pc;
4484 // it is not guaranteed to mode switch (different in ARMv6 and
4486 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4488 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4489 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4490 Insn_template::arm_insn(0xe12fff1c), // bx ip
4491 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4492 // dcd R_ARM_REL32(X)
4495 // V4T ARM -> ARM long branch stub, PIC.
4496 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4498 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4499 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4500 Insn_template::arm_insn(0xe12fff1c), // bx ip
4501 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4502 // dcd R_ARM_REL32(X)
4505 // V4T Thumb -> ARM long branch stub, PIC.
4506 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4508 Insn_template::thumb16_insn(0x4778), // bx pc
4509 Insn_template::thumb16_insn(0x46c0), // nop
4510 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4511 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4512 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4513 // dcd R_ARM_REL32(X)
4516 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4518 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4520 Insn_template::thumb16_insn(0xb401), // push {r0}
4521 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4522 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4523 Insn_template::thumb16_insn(0x4484), // add ip, r0
4524 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4525 Insn_template::thumb16_insn(0x4760), // bx ip
4526 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4527 // dcd R_ARM_REL32(X)
4530 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4532 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4534 Insn_template::thumb16_insn(0x4778), // bx pc
4535 Insn_template::thumb16_insn(0x46c0), // nop
4536 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4537 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4538 Insn_template::arm_insn(0xe12fff1c), // bx ip
4539 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4540 // dcd R_ARM_REL32(X)
4543 // Cortex-A8 erratum-workaround stubs.
4545 // Stub used for conditional branches (which may be beyond +/-1MB away,
4546 // so we can't use a conditional branch to reach this stub).
4553 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4555 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4556 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4557 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4561 // Stub used for b.w and bl.w instructions.
4563 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4565 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4568 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4570 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4573 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4574 // instruction (which switches to ARM mode) to point to this stub. Jump to
4575 // the real destination using an ARM-mode branch.
4576 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4578 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4581 // Stub used to provide an interworking for R_ARM_V4BX relocation
4582 // (bx r[n] instruction).
4583 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4585 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4586 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4587 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4590 // Fill in the stub template look-up table. Stub templates are constructed
4591 // per instance of Stub_factory for fast look-up without locking
4592 // in a thread-enabled environment.
4594 this->stub_templates_[arm_stub_none] =
4595 new Stub_template(arm_stub_none, NULL, 0);
4597 #define DEF_STUB(x) \
4601 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4602 Stub_type type = arm_stub_##x; \
4603 this->stub_templates_[type] = \
4604 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4612 // Stub_table methods.
4614 // Removel all Cortex-A8 stub.
4616 template<bool big_endian>
4618 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4620 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4621 p != this->cortex_a8_stubs_.end();
4624 this->cortex_a8_stubs_.clear();
4627 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4629 template<bool big_endian>
4631 Stub_table<big_endian>::relocate_stub(
4633 const Relocate_info<32, big_endian>* relinfo,
4634 Target_arm<big_endian>* arm_target,
4635 Output_section* output_section,
4636 unsigned char* view,
4637 Arm_address address,
4638 section_size_type view_size)
4640 const Stub_template* stub_template = stub->stub_template();
4641 if (stub_template->reloc_count() != 0)
4643 // Adjust view to cover the stub only.
4644 section_size_type offset = stub->offset();
4645 section_size_type stub_size = stub_template->size();
4646 gold_assert(offset + stub_size <= view_size);
4648 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4649 address + offset, stub_size);
4653 // Relocate all stubs in this stub table.
4655 template<bool big_endian>
4657 Stub_table<big_endian>::relocate_stubs(
4658 const Relocate_info<32, big_endian>* relinfo,
4659 Target_arm<big_endian>* arm_target,
4660 Output_section* output_section,
4661 unsigned char* view,
4662 Arm_address address,
4663 section_size_type view_size)
4665 // If we are passed a view bigger than the stub table's. we need to
4667 gold_assert(address == this->address()
4669 == static_cast<section_size_type>(this->data_size())));
4671 // Relocate all relocation stubs.
4672 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4673 p != this->reloc_stubs_.end();
4675 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4676 address, view_size);
4678 // Relocate all Cortex-A8 stubs.
4679 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4680 p != this->cortex_a8_stubs_.end();
4682 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4683 address, view_size);
4685 // Relocate all ARM V4BX stubs.
4686 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4687 p != this->arm_v4bx_stubs_.end();
4691 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4692 address, view_size);
4696 // Write out the stubs to file.
4698 template<bool big_endian>
4700 Stub_table<big_endian>::do_write(Output_file* of)
4702 off_t offset = this->offset();
4703 const section_size_type oview_size =
4704 convert_to_section_size_type(this->data_size());
4705 unsigned char* const oview = of->get_output_view(offset, oview_size);
4707 // Write relocation stubs.
4708 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4709 p != this->reloc_stubs_.end();
4712 Reloc_stub* stub = p->second;
4713 Arm_address address = this->address() + stub->offset();
4715 == align_address(address,
4716 stub->stub_template()->alignment()));
4717 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4721 // Write Cortex-A8 stubs.
4722 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4723 p != this->cortex_a8_stubs_.end();
4726 Cortex_a8_stub* stub = p->second;
4727 Arm_address address = this->address() + stub->offset();
4729 == align_address(address,
4730 stub->stub_template()->alignment()));
4731 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4735 // Write ARM V4BX relocation stubs.
4736 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4737 p != this->arm_v4bx_stubs_.end();
4743 Arm_address address = this->address() + (*p)->offset();
4745 == align_address(address,
4746 (*p)->stub_template()->alignment()));
4747 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4751 of->write_output_view(this->offset(), oview_size, oview);
4754 // Update the data size and address alignment of the stub table at the end
4755 // of a relaxation pass. Return true if either the data size or the
4756 // alignment changed in this relaxation pass.
4758 template<bool big_endian>
4760 Stub_table<big_endian>::update_data_size_and_addralign()
4762 // Go over all stubs in table to compute data size and address alignment.
4763 off_t size = this->reloc_stubs_size_;
4764 unsigned addralign = this->reloc_stubs_addralign_;
4766 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4767 p != this->cortex_a8_stubs_.end();
4770 const Stub_template* stub_template = p->second->stub_template();
4771 addralign = std::max(addralign, stub_template->alignment());
4772 size = (align_address(size, stub_template->alignment())
4773 + stub_template->size());
4776 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4777 p != this->arm_v4bx_stubs_.end();
4783 const Stub_template* stub_template = (*p)->stub_template();
4784 addralign = std::max(addralign, stub_template->alignment());
4785 size = (align_address(size, stub_template->alignment())
4786 + stub_template->size());
4789 // Check if either data size or alignment changed in this pass.
4790 // Update prev_data_size_ and prev_addralign_. These will be used
4791 // as the current data size and address alignment for the next pass.
4792 bool changed = size != this->prev_data_size_;
4793 this->prev_data_size_ = size;
4795 if (addralign != this->prev_addralign_)
4797 this->prev_addralign_ = addralign;
4802 // Finalize the stubs. This sets the offsets of the stubs within the stub
4803 // table. It also marks all input sections needing Cortex-A8 workaround.
4805 template<bool big_endian>
4807 Stub_table<big_endian>::finalize_stubs()
4809 off_t off = this->reloc_stubs_size_;
4810 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4811 p != this->cortex_a8_stubs_.end();
4814 Cortex_a8_stub* stub = p->second;
4815 const Stub_template* stub_template = stub->stub_template();
4816 uint64_t stub_addralign = stub_template->alignment();
4817 off = align_address(off, stub_addralign);
4818 stub->set_offset(off);
4819 off += stub_template->size();
4821 // Mark input section so that we can determine later if a code section
4822 // needs the Cortex-A8 workaround quickly.
4823 Arm_relobj<big_endian>* arm_relobj =
4824 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
4825 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
4828 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4829 p != this->arm_v4bx_stubs_.end();
4835 const Stub_template* stub_template = (*p)->stub_template();
4836 uint64_t stub_addralign = stub_template->alignment();
4837 off = align_address(off, stub_addralign);
4838 (*p)->set_offset(off);
4839 off += stub_template->size();
4842 gold_assert(off <= this->prev_data_size_);
4845 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
4846 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
4847 // of the address range seen by the linker.
4849 template<bool big_endian>
4851 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
4852 Target_arm<big_endian>* arm_target,
4853 unsigned char* view,
4854 Arm_address view_address,
4855 section_size_type view_size)
4857 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
4858 for (Cortex_a8_stub_list::const_iterator p =
4859 this->cortex_a8_stubs_.lower_bound(view_address);
4860 ((p != this->cortex_a8_stubs_.end())
4861 && (p->first < (view_address + view_size)));
4864 // We do not store the THUMB bit in the LSB of either the branch address
4865 // or the stub offset. There is no need to strip the LSB.
4866 Arm_address branch_address = p->first;
4867 const Cortex_a8_stub* stub = p->second;
4868 Arm_address stub_address = this->address() + stub->offset();
4870 // Offset of the branch instruction relative to this view.
4871 section_size_type offset =
4872 convert_to_section_size_type(branch_address - view_address);
4873 gold_assert((offset + 4) <= view_size);
4875 arm_target->apply_cortex_a8_workaround(stub, stub_address,
4876 view + offset, branch_address);
4880 // Arm_input_section methods.
4882 // Initialize an Arm_input_section.
4884 template<bool big_endian>
4886 Arm_input_section<big_endian>::init()
4888 Relobj* relobj = this->relobj();
4889 unsigned int shndx = this->shndx();
4891 // Cache these to speed up size and alignment queries. It is too slow
4892 // to call section_addraglin and section_size every time.
4893 this->original_addralign_ = relobj->section_addralign(shndx);
4894 this->original_size_ = relobj->section_size(shndx);
4896 // We want to make this look like the original input section after
4897 // output sections are finalized.
4898 Output_section* os = relobj->output_section(shndx);
4899 off_t offset = relobj->output_section_offset(shndx);
4900 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
4901 this->set_address(os->address() + offset);
4902 this->set_file_offset(os->offset() + offset);
4904 this->set_current_data_size(this->original_size_);
4905 this->finalize_data_size();
4908 template<bool big_endian>
4910 Arm_input_section<big_endian>::do_write(Output_file* of)
4912 // We have to write out the original section content.
4913 section_size_type section_size;
4914 const unsigned char* section_contents =
4915 this->relobj()->section_contents(this->shndx(), §ion_size, false);
4916 of->write(this->offset(), section_contents, section_size);
4918 // If this owns a stub table and it is not empty, write it.
4919 if (this->is_stub_table_owner() && !this->stub_table_->empty())
4920 this->stub_table_->write(of);
4923 // Finalize data size.
4925 template<bool big_endian>
4927 Arm_input_section<big_endian>::set_final_data_size()
4929 // If this owns a stub table, finalize its data size as well.
4930 if (this->is_stub_table_owner())
4932 uint64_t address = this->address();
4934 // The stub table comes after the original section contents.
4935 address += this->original_size_;
4936 address = align_address(address, this->stub_table_->addralign());
4937 off_t offset = this->offset() + (address - this->address());
4938 this->stub_table_->set_address_and_file_offset(address, offset);
4939 address += this->stub_table_->data_size();
4940 gold_assert(address == this->address() + this->current_data_size());
4943 this->set_data_size(this->current_data_size());
4946 // Reset address and file offset.
4948 template<bool big_endian>
4950 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
4952 // Size of the original input section contents.
4953 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
4955 // If this is a stub table owner, account for the stub table size.
4956 if (this->is_stub_table_owner())
4958 Stub_table<big_endian>* stub_table = this->stub_table_;
4960 // Reset the stub table's address and file offset. The
4961 // current data size for child will be updated after that.
4962 stub_table_->reset_address_and_file_offset();
4963 off = align_address(off, stub_table_->addralign());
4964 off += stub_table->current_data_size();
4967 this->set_current_data_size(off);
4970 // Arm_exidx_cantunwind methods.
4972 // Write this to Output file OF for a fixed endianity.
4974 template<bool big_endian>
4976 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
4978 off_t offset = this->offset();
4979 const section_size_type oview_size = 8;
4980 unsigned char* const oview = of->get_output_view(offset, oview_size);
4982 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
4983 Valtype* wv = reinterpret_cast<Valtype*>(oview);
4985 Output_section* os = this->relobj_->output_section(this->shndx_);
4986 gold_assert(os != NULL);
4988 Arm_relobj<big_endian>* arm_relobj =
4989 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
4990 Arm_address output_offset =
4991 arm_relobj->get_output_section_offset(this->shndx_);
4992 Arm_address section_start;
4993 if(output_offset != Arm_relobj<big_endian>::invalid_address)
4994 section_start = os->address() + output_offset;
4997 // Currently this only happens for a relaxed section.
4998 const Output_relaxed_input_section* poris =
4999 os->find_relaxed_input_section(this->relobj_, this->shndx_);
5000 gold_assert(poris != NULL);
5001 section_start = poris->address();
5004 // We always append this to the end of an EXIDX section.
5005 Arm_address output_address =
5006 section_start + this->relobj_->section_size(this->shndx_);
5008 // Write out the entry. The first word either points to the beginning
5009 // or after the end of a text section. The second word is the special
5010 // EXIDX_CANTUNWIND value.
5011 uint32_t prel31_offset = output_address - this->address();
5012 if (utils::has_overflow<31>(offset))
5013 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
5014 elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
5015 elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
5017 of->write_output_view(this->offset(), oview_size, oview);
5020 // Arm_exidx_merged_section methods.
5022 // Constructor for Arm_exidx_merged_section.
5023 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5024 // SECTION_OFFSET_MAP points to a section offset map describing how
5025 // parts of the input section are mapped to output. DELETED_BYTES is
5026 // the number of bytes deleted from the EXIDX input section.
5028 Arm_exidx_merged_section::Arm_exidx_merged_section(
5029 const Arm_exidx_input_section& exidx_input_section,
5030 const Arm_exidx_section_offset_map& section_offset_map,
5031 uint32_t deleted_bytes)
5032 : Output_relaxed_input_section(exidx_input_section.relobj(),
5033 exidx_input_section.shndx(),
5034 exidx_input_section.addralign()),
5035 exidx_input_section_(exidx_input_section),
5036 section_offset_map_(section_offset_map)
5038 // Fix size here so that we do not need to implement set_final_data_size.
5039 this->set_data_size(exidx_input_section.size() - deleted_bytes);
5040 this->fix_data_size();
5043 // Given an input OBJECT, an input section index SHNDX within that
5044 // object, and an OFFSET relative to the start of that input
5045 // section, return whether or not the corresponding offset within
5046 // the output section is known. If this function returns true, it
5047 // sets *POUTPUT to the output offset. The value -1 indicates that
5048 // this input offset is being discarded.
5051 Arm_exidx_merged_section::do_output_offset(
5052 const Relobj* relobj,
5054 section_offset_type offset,
5055 section_offset_type* poutput) const
5057 // We only handle offsets for the original EXIDX input section.
5058 if (relobj != this->exidx_input_section_.relobj()
5059 || shndx != this->exidx_input_section_.shndx())
5062 section_offset_type section_size =
5063 convert_types<section_offset_type>(this->exidx_input_section_.size());
5064 if (offset < 0 || offset >= section_size)
5065 // Input offset is out of valid range.
5069 // We need to look up the section offset map to determine the output
5070 // offset. Find the reference point in map that is first offset
5071 // bigger than or equal to this offset.
5072 Arm_exidx_section_offset_map::const_iterator p =
5073 this->section_offset_map_.lower_bound(offset);
5075 // The section offset maps are build such that this should not happen if
5076 // input offset is in the valid range.
5077 gold_assert(p != this->section_offset_map_.end());
5079 // We need to check if this is dropped.
5080 section_offset_type ref = p->first;
5081 section_offset_type mapped_ref = p->second;
5083 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5084 // Offset is present in output.
5085 *poutput = mapped_ref + (offset - ref);
5087 // Offset is discarded owing to EXIDX entry merging.
5094 // Write this to output file OF.
5097 Arm_exidx_merged_section::do_write(Output_file* of)
5099 // If we retain or discard the whole EXIDX input section, we would
5101 gold_assert(this->data_size() != this->exidx_input_section_.size()
5102 && this->data_size() != 0);
5104 off_t offset = this->offset();
5105 const section_size_type oview_size = this->data_size();
5106 unsigned char* const oview = of->get_output_view(offset, oview_size);
5108 Output_section* os = this->relobj()->output_section(this->shndx());
5109 gold_assert(os != NULL);
5111 // Get contents of EXIDX input section.
5112 section_size_type section_size;
5113 const unsigned char* section_contents =
5114 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5115 gold_assert(section_size == this->exidx_input_section_.size());
5117 // Go over spans of input offsets and write only those that are not
5119 section_offset_type in_start = 0;
5120 section_offset_type out_start = 0;
5121 for(Arm_exidx_section_offset_map::const_iterator p =
5122 this->section_offset_map_.begin();
5123 p != this->section_offset_map_.end();
5126 section_offset_type in_end = p->first;
5127 gold_assert(in_end >= in_start);
5128 section_offset_type out_end = p->second;
5129 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5132 size_t out_chunk_size =
5133 convert_types<size_t>(out_end - out_start + 1);
5134 gold_assert(out_chunk_size == in_chunk_size);
5135 memcpy(oview + out_start, section_contents + in_start,
5137 out_start += out_chunk_size;
5139 in_start += in_chunk_size;
5142 gold_assert(convert_to_section_size_type(out_start) == oview_size);
5143 of->write_output_view(this->offset(), oview_size, oview);
5146 // Arm_exidx_fixup methods.
5148 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5149 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5150 // points to the end of the last seen EXIDX section.
5153 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5155 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5156 && this->last_input_section_ != NULL)
5158 Relobj* relobj = this->last_input_section_->relobj();
5159 unsigned int text_shndx = this->last_input_section_->link();
5160 Arm_exidx_cantunwind* cantunwind =
5161 new Arm_exidx_cantunwind(relobj, text_shndx);
5162 this->exidx_output_section_->add_output_section_data(cantunwind);
5163 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5167 // Process an EXIDX section entry in input. Return whether this entry
5168 // can be deleted in the output. SECOND_WORD in the second word of the
5172 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5175 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5177 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5178 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5179 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5181 else if ((second_word & 0x80000000) != 0)
5183 // Inlined unwinding data. Merge if equal to previous.
5184 delete_entry = (this->last_unwind_type_ == UT_INLINED_ENTRY
5185 && this->last_inlined_entry_ == second_word);
5186 this->last_unwind_type_ = UT_INLINED_ENTRY;
5187 this->last_inlined_entry_ = second_word;
5191 // Normal table entry. In theory we could merge these too,
5192 // but duplicate entries are likely to be much less common.
5193 delete_entry = false;
5194 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5196 return delete_entry;
5199 // Update the current section offset map during EXIDX section fix-up.
5200 // If there is no map, create one. INPUT_OFFSET is the offset of a
5201 // reference point, DELETED_BYTES is the number of deleted by in the
5202 // section so far. If DELETE_ENTRY is true, the reference point and
5203 // all offsets after the previous reference point are discarded.
5206 Arm_exidx_fixup::update_offset_map(
5207 section_offset_type input_offset,
5208 section_size_type deleted_bytes,
5211 if (this->section_offset_map_ == NULL)
5212 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5213 section_offset_type output_offset;
5215 output_offset = Arm_exidx_input_section::invalid_offset;
5217 output_offset = input_offset - deleted_bytes;
5218 (*this->section_offset_map_)[input_offset] = output_offset;
5221 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5222 // bytes deleted. If some entries are merged, also store a pointer to a newly
5223 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5224 // caller owns the map and is responsible for releasing it after use.
5226 template<bool big_endian>
5228 Arm_exidx_fixup::process_exidx_section(
5229 const Arm_exidx_input_section* exidx_input_section,
5230 Arm_exidx_section_offset_map** psection_offset_map)
5232 Relobj* relobj = exidx_input_section->relobj();
5233 unsigned shndx = exidx_input_section->shndx();
5234 section_size_type section_size;
5235 const unsigned char* section_contents =
5236 relobj->section_contents(shndx, §ion_size, false);
5238 if ((section_size % 8) != 0)
5240 // Something is wrong with this section. Better not touch it.
5241 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5242 relobj->name().c_str(), shndx);
5243 this->last_input_section_ = exidx_input_section;
5244 this->last_unwind_type_ = UT_NONE;
5248 uint32_t deleted_bytes = 0;
5249 bool prev_delete_entry = false;
5250 gold_assert(this->section_offset_map_ == NULL);
5252 for (section_size_type i = 0; i < section_size; i += 8)
5254 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5256 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5257 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5259 bool delete_entry = this->process_exidx_entry(second_word);
5261 // Entry deletion causes changes in output offsets. We use a std::map
5262 // to record these. And entry (x, y) means input offset x
5263 // is mapped to output offset y. If y is invalid_offset, then x is
5264 // dropped in the output. Because of the way std::map::lower_bound
5265 // works, we record the last offset in a region w.r.t to keeping or
5266 // dropping. If there is no entry (x0, y0) for an input offset x0,
5267 // the output offset y0 of it is determined by the output offset y1 of
5268 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5269 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5271 if (delete_entry != prev_delete_entry && i != 0)
5272 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5274 // Update total deleted bytes for this entry.
5278 prev_delete_entry = delete_entry;
5281 // If section offset map is not NULL, make an entry for the end of
5283 if (this->section_offset_map_ != NULL)
5284 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5286 *psection_offset_map = this->section_offset_map_;
5287 this->section_offset_map_ = NULL;
5288 this->last_input_section_ = exidx_input_section;
5290 // Set the first output text section so that we can link the EXIDX output
5291 // section to it. Ignore any EXIDX input section that is completely merged.
5292 if (this->first_output_text_section_ == NULL
5293 && deleted_bytes != section_size)
5295 unsigned int link = exidx_input_section->link();
5296 Output_section* os = relobj->output_section(link);
5297 gold_assert(os != NULL);
5298 this->first_output_text_section_ = os;
5301 return deleted_bytes;
5304 // Arm_output_section methods.
5306 // Create a stub group for input sections from BEGIN to END. OWNER
5307 // points to the input section to be the owner a new stub table.
5309 template<bool big_endian>
5311 Arm_output_section<big_endian>::create_stub_group(
5312 Input_section_list::const_iterator begin,
5313 Input_section_list::const_iterator end,
5314 Input_section_list::const_iterator owner,
5315 Target_arm<big_endian>* target,
5316 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
5318 // We use a different kind of relaxed section in an EXIDX section.
5319 // The static casting from Output_relaxed_input_section to
5320 // Arm_input_section is invalid in an EXIDX section. We are okay
5321 // because we should not be calling this for an EXIDX section.
5322 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5324 // Currently we convert ordinary input sections into relaxed sections only
5325 // at this point but we may want to support creating relaxed input section
5326 // very early. So we check here to see if owner is already a relaxed
5329 Arm_input_section<big_endian>* arm_input_section;
5330 if (owner->is_relaxed_input_section())
5333 Arm_input_section<big_endian>::as_arm_input_section(
5334 owner->relaxed_input_section());
5338 gold_assert(owner->is_input_section());
5339 // Create a new relaxed input section.
5341 target->new_arm_input_section(owner->relobj(), owner->shndx());
5342 new_relaxed_sections->push_back(arm_input_section);
5345 // Create a stub table.
5346 Stub_table<big_endian>* stub_table =
5347 target->new_stub_table(arm_input_section);
5349 arm_input_section->set_stub_table(stub_table);
5351 Input_section_list::const_iterator p = begin;
5352 Input_section_list::const_iterator prev_p;
5354 // Look for input sections or relaxed input sections in [begin ... end].
5357 if (p->is_input_section() || p->is_relaxed_input_section())
5359 // The stub table information for input sections live
5360 // in their objects.
5361 Arm_relobj<big_endian>* arm_relobj =
5362 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5363 arm_relobj->set_stub_table(p->shndx(), stub_table);
5367 while (prev_p != end);
5370 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5371 // of stub groups. We grow a stub group by adding input section until the
5372 // size is just below GROUP_SIZE. The last input section will be converted
5373 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5374 // input section after the stub table, effectively double the group size.
5376 // This is similar to the group_sections() function in elf32-arm.c but is
5377 // implemented differently.
5379 template<bool big_endian>
5381 Arm_output_section<big_endian>::group_sections(
5382 section_size_type group_size,
5383 bool stubs_always_after_branch,
5384 Target_arm<big_endian>* target)
5386 // We only care about sections containing code.
5387 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5390 // States for grouping.
5393 // No group is being built.
5395 // A group is being built but the stub table is not found yet.
5396 // We keep group a stub group until the size is just under GROUP_SIZE.
5397 // The last input section in the group will be used as the stub table.
5398 FINDING_STUB_SECTION,
5399 // A group is being built and we have already found a stub table.
5400 // We enter this state to grow a stub group by adding input section
5401 // after the stub table. This effectively doubles the group size.
5405 // Any newly created relaxed sections are stored here.
5406 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5408 State state = NO_GROUP;
5409 section_size_type off = 0;
5410 section_size_type group_begin_offset = 0;
5411 section_size_type group_end_offset = 0;
5412 section_size_type stub_table_end_offset = 0;
5413 Input_section_list::const_iterator group_begin =
5414 this->input_sections().end();
5415 Input_section_list::const_iterator stub_table =
5416 this->input_sections().end();
5417 Input_section_list::const_iterator group_end = this->input_sections().end();
5418 for (Input_section_list::const_iterator p = this->input_sections().begin();
5419 p != this->input_sections().end();
5422 section_size_type section_begin_offset =
5423 align_address(off, p->addralign());
5424 section_size_type section_end_offset =
5425 section_begin_offset + p->data_size();
5427 // Check to see if we should group the previously seens sections.
5433 case FINDING_STUB_SECTION:
5434 // Adding this section makes the group larger than GROUP_SIZE.
5435 if (section_end_offset - group_begin_offset >= group_size)
5437 if (stubs_always_after_branch)
5439 gold_assert(group_end != this->input_sections().end());
5440 this->create_stub_group(group_begin, group_end, group_end,
5441 target, &new_relaxed_sections);
5446 // But wait, there's more! Input sections up to
5447 // stub_group_size bytes after the stub table can be
5448 // handled by it too.
5449 state = HAS_STUB_SECTION;
5450 stub_table = group_end;
5451 stub_table_end_offset = group_end_offset;
5456 case HAS_STUB_SECTION:
5457 // Adding this section makes the post stub-section group larger
5459 if (section_end_offset - stub_table_end_offset >= group_size)
5461 gold_assert(group_end != this->input_sections().end());
5462 this->create_stub_group(group_begin, group_end, stub_table,
5463 target, &new_relaxed_sections);
5472 // If we see an input section and currently there is no group, start
5473 // a new one. Skip any empty sections.
5474 if ((p->is_input_section() || p->is_relaxed_input_section())
5475 && (p->relobj()->section_size(p->shndx()) != 0))
5477 if (state == NO_GROUP)
5479 state = FINDING_STUB_SECTION;
5481 group_begin_offset = section_begin_offset;
5484 // Keep track of the last input section seen.
5486 group_end_offset = section_end_offset;
5489 off = section_end_offset;
5492 // Create a stub group for any ungrouped sections.
5493 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5495 gold_assert(group_end != this->input_sections().end());
5496 this->create_stub_group(group_begin, group_end,
5497 (state == FINDING_STUB_SECTION
5500 target, &new_relaxed_sections);
5503 // Convert input section into relaxed input section in a batch.
5504 if (!new_relaxed_sections.empty())
5505 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5507 // Update the section offsets
5508 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5510 Arm_relobj<big_endian>* arm_relobj =
5511 Arm_relobj<big_endian>::as_arm_relobj(
5512 new_relaxed_sections[i]->relobj());
5513 unsigned int shndx = new_relaxed_sections[i]->shndx();
5514 // Tell Arm_relobj that this input section is converted.
5515 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5519 // Append non empty text sections in this to LIST in ascending
5520 // order of their position in this.
5522 template<bool big_endian>
5524 Arm_output_section<big_endian>::append_text_sections_to_list(
5525 Text_section_list* list)
5527 // We only care about text sections.
5528 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5531 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5533 for (Input_section_list::const_iterator p = this->input_sections().begin();
5534 p != this->input_sections().end();
5537 // We only care about plain or relaxed input sections. We also
5538 // ignore any merged sections.
5539 if ((p->is_input_section() || p->is_relaxed_input_section())
5540 && p->data_size() != 0)
5541 list->push_back(Text_section_list::value_type(p->relobj(),
5546 template<bool big_endian>
5548 Arm_output_section<big_endian>::fix_exidx_coverage(
5550 const Text_section_list& sorted_text_sections,
5551 Symbol_table* symtab)
5553 // We should only do this for the EXIDX output section.
5554 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5556 // We don't want the relaxation loop to undo these changes, so we discard
5557 // the current saved states and take another one after the fix-up.
5558 this->discard_states();
5560 // Remove all input sections.
5561 uint64_t address = this->address();
5562 typedef std::list<Simple_input_section> Simple_input_section_list;
5563 Simple_input_section_list input_sections;
5564 this->reset_address_and_file_offset();
5565 this->get_input_sections(address, std::string(""), &input_sections);
5567 if (!this->input_sections().empty())
5568 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5570 // Go through all the known input sections and record them.
5571 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5572 Section_id_set known_input_sections;
5573 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5574 p != input_sections.end();
5577 // This should never happen. At this point, we should only see
5578 // plain EXIDX input sections.
5579 gold_assert(!p->is_relaxed_input_section());
5580 known_input_sections.insert(Section_id(p->relobj(), p->shndx()));
5583 Arm_exidx_fixup exidx_fixup(this);
5585 // Go over the sorted text sections.
5586 Section_id_set processed_input_sections;
5587 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5588 p != sorted_text_sections.end();
5591 Relobj* relobj = p->first;
5592 unsigned int shndx = p->second;
5594 Arm_relobj<big_endian>* arm_relobj =
5595 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5596 const Arm_exidx_input_section* exidx_input_section =
5597 arm_relobj->exidx_input_section_by_link(shndx);
5599 // If this text section has no EXIDX section, force an EXIDX_CANTUNWIND
5600 // entry pointing to the end of the last seen EXIDX section.
5601 if (exidx_input_section == NULL)
5603 exidx_fixup.add_exidx_cantunwind_as_needed();
5607 Relobj* exidx_relobj = exidx_input_section->relobj();
5608 unsigned int exidx_shndx = exidx_input_section->shndx();
5609 Section_id sid(exidx_relobj, exidx_shndx);
5610 if (known_input_sections.find(sid) == known_input_sections.end())
5612 // This is odd. We have not seen this EXIDX input section before.
5613 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5614 // issue a warning instead. We assume the user knows what he
5615 // or she is doing. Otherwise, this is an error.
5616 if (layout->script_options()->saw_sections_clause())
5617 gold_warning(_("unwinding may not work because EXIDX input section"
5618 " %u of %s is not in EXIDX output section"),
5619 exidx_shndx, exidx_relobj->name().c_str());
5621 gold_error(_("unwinding may not work because EXIDX input section"
5622 " %u of %s is not in EXIDX output section"),
5623 exidx_shndx, exidx_relobj->name().c_str());
5625 exidx_fixup.add_exidx_cantunwind_as_needed();
5629 // Fix up coverage and append input section to output data list.
5630 Arm_exidx_section_offset_map* section_offset_map = NULL;
5631 uint32_t deleted_bytes =
5632 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5633 §ion_offset_map);
5635 if (deleted_bytes == exidx_input_section->size())
5637 // The whole EXIDX section got merged. Remove it from output.
5638 gold_assert(section_offset_map == NULL);
5639 exidx_relobj->set_output_section(exidx_shndx, NULL);
5641 // All local symbols defined in this input section will be dropped.
5642 // We need to adjust output local symbol count.
5643 arm_relobj->set_output_local_symbol_count_needs_update();
5645 else if (deleted_bytes > 0)
5647 // Some entries are merged. We need to convert this EXIDX input
5648 // section into a relaxed section.
5649 gold_assert(section_offset_map != NULL);
5650 Arm_exidx_merged_section* merged_section =
5651 new Arm_exidx_merged_section(*exidx_input_section,
5652 *section_offset_map, deleted_bytes);
5653 this->add_relaxed_input_section(merged_section);
5654 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5656 // All local symbols defined in discarded portions of this input
5657 // section will be dropped. We need to adjust output local symbol
5659 arm_relobj->set_output_local_symbol_count_needs_update();
5663 // Just add back the EXIDX input section.
5664 gold_assert(section_offset_map == NULL);
5665 Output_section::Simple_input_section sis(exidx_relobj, exidx_shndx);
5666 this->add_simple_input_section(sis, exidx_input_section->size(),
5667 exidx_input_section->addralign());
5670 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5673 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5674 exidx_fixup.add_exidx_cantunwind_as_needed();
5676 // Remove any known EXIDX input sections that are not processed.
5677 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5678 p != input_sections.end();
5681 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5682 == processed_input_sections.end())
5684 // We only discard a known EXIDX section because its linked
5685 // text section has been folded by ICF.
5686 Arm_relobj<big_endian>* arm_relobj =
5687 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5688 const Arm_exidx_input_section* exidx_input_section =
5689 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5690 gold_assert(exidx_input_section != NULL);
5691 unsigned int text_shndx = exidx_input_section->link();
5692 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5694 // Remove this from link.
5695 p->relobj()->set_output_section(p->shndx(), NULL);
5699 // Link exidx output section to the first seen output section and
5700 // set correct entry size.
5701 this->set_link_section(exidx_fixup.first_output_text_section());
5702 this->set_entsize(8);
5704 // Make changes permanent.
5705 this->save_states();
5706 this->set_section_offsets_need_adjustment();
5709 // Arm_relobj methods.
5711 // Determine if an input section is scannable for stub processing. SHDR is
5712 // the header of the section and SHNDX is the section index. OS is the output
5713 // section for the input section and SYMTAB is the global symbol table used to
5714 // look up ICF information.
5716 template<bool big_endian>
5718 Arm_relobj<big_endian>::section_is_scannable(
5719 const elfcpp::Shdr<32, big_endian>& shdr,
5721 const Output_section* os,
5722 const Symbol_table *symtab)
5724 // Skip any empty sections, unallocated sections or sections whose
5725 // type are not SHT_PROGBITS.
5726 if (shdr.get_sh_size() == 0
5727 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
5728 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
5731 // Skip any discarded or ICF'ed sections.
5732 if (os == NULL || symtab->is_section_folded(this, shndx))
5735 // If this requires special offset handling, check to see if it is
5736 // a relaxed section. If this is not, then it is a merged section that
5737 // we cannot handle.
5738 if (this->is_output_section_offset_invalid(shndx))
5740 const Output_relaxed_input_section* poris =
5741 os->find_relaxed_input_section(this, shndx);
5749 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5750 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5752 template<bool big_endian>
5754 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
5755 const elfcpp::Shdr<32, big_endian>& shdr,
5756 const Relobj::Output_sections& out_sections,
5757 const Symbol_table *symtab,
5758 const unsigned char* pshdrs)
5760 unsigned int sh_type = shdr.get_sh_type();
5761 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
5764 // Ignore empty section.
5765 off_t sh_size = shdr.get_sh_size();
5769 // Ignore reloc section with unexpected symbol table. The
5770 // error will be reported in the final link.
5771 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
5774 unsigned int reloc_size;
5775 if (sh_type == elfcpp::SHT_REL)
5776 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5778 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5780 // Ignore reloc section with unexpected entsize or uneven size.
5781 // The error will be reported in the final link.
5782 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
5785 // Ignore reloc section with bad info. This error will be
5786 // reported in the final link.
5787 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5788 if (index >= this->shnum())
5791 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5792 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
5793 return this->section_is_scannable(text_shdr, index,
5794 out_sections[index], symtab);
5797 // Return the output address of either a plain input section or a relaxed
5798 // input section. SHNDX is the section index. We define and use this
5799 // instead of calling Output_section::output_address because that is slow
5800 // for large output.
5802 template<bool big_endian>
5804 Arm_relobj<big_endian>::simple_input_section_output_address(
5808 if (this->is_output_section_offset_invalid(shndx))
5810 const Output_relaxed_input_section* poris =
5811 os->find_relaxed_input_section(this, shndx);
5812 // We do not handle merged sections here.
5813 gold_assert(poris != NULL);
5814 return poris->address();
5817 return os->address() + this->get_output_section_offset(shndx);
5820 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
5821 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5823 template<bool big_endian>
5825 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
5826 const elfcpp::Shdr<32, big_endian>& shdr,
5829 const Symbol_table* symtab)
5831 if (!this->section_is_scannable(shdr, shndx, os, symtab))
5834 // If the section does not cross any 4K-boundaries, it does not need to
5836 Arm_address address = this->simple_input_section_output_address(shndx, os);
5837 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
5843 // Scan a section for Cortex-A8 workaround.
5845 template<bool big_endian>
5847 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
5848 const elfcpp::Shdr<32, big_endian>& shdr,
5851 Target_arm<big_endian>* arm_target)
5853 // Look for the first mapping symbol in this section. It should be
5855 Mapping_symbol_position section_start(shndx, 0);
5856 typename Mapping_symbols_info::const_iterator p =
5857 this->mapping_symbols_info_.lower_bound(section_start);
5859 // There are no mapping symbols for this section. Treat it as a data-only
5861 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
5864 Arm_address output_address =
5865 this->simple_input_section_output_address(shndx, os);
5867 // Get the section contents.
5868 section_size_type input_view_size = 0;
5869 const unsigned char* input_view =
5870 this->section_contents(shndx, &input_view_size, false);
5872 // We need to go through the mapping symbols to determine what to
5873 // scan. There are two reasons. First, we should look at THUMB code and
5874 // THUMB code only. Second, we only want to look at the 4K-page boundary
5875 // to speed up the scanning.
5877 while (p != this->mapping_symbols_info_.end()
5878 && p->first.first == shndx)
5880 typename Mapping_symbols_info::const_iterator next =
5881 this->mapping_symbols_info_.upper_bound(p->first);
5883 // Only scan part of a section with THUMB code.
5884 if (p->second == 't')
5886 // Determine the end of this range.
5887 section_size_type span_start =
5888 convert_to_section_size_type(p->first.second);
5889 section_size_type span_end;
5890 if (next != this->mapping_symbols_info_.end()
5891 && next->first.first == shndx)
5892 span_end = convert_to_section_size_type(next->first.second);
5894 span_end = convert_to_section_size_type(shdr.get_sh_size());
5896 if (((span_start + output_address) & ~0xfffUL)
5897 != ((span_end + output_address - 1) & ~0xfffUL))
5899 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
5900 span_start, span_end,
5910 // Scan relocations for stub generation.
5912 template<bool big_endian>
5914 Arm_relobj<big_endian>::scan_sections_for_stubs(
5915 Target_arm<big_endian>* arm_target,
5916 const Symbol_table* symtab,
5917 const Layout* layout)
5919 unsigned int shnum = this->shnum();
5920 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5922 // Read the section headers.
5923 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
5927 // To speed up processing, we set up hash tables for fast lookup of
5928 // input offsets to output addresses.
5929 this->initialize_input_to_output_maps();
5931 const Relobj::Output_sections& out_sections(this->output_sections());
5933 Relocate_info<32, big_endian> relinfo;
5934 relinfo.symtab = symtab;
5935 relinfo.layout = layout;
5936 relinfo.object = this;
5938 // Do relocation stubs scanning.
5939 const unsigned char* p = pshdrs + shdr_size;
5940 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
5942 const elfcpp::Shdr<32, big_endian> shdr(p);
5943 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
5946 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5947 Arm_address output_offset = this->get_output_section_offset(index);
5948 Arm_address output_address;
5949 if(output_offset != invalid_address)
5950 output_address = out_sections[index]->address() + output_offset;
5953 // Currently this only happens for a relaxed section.
5954 const Output_relaxed_input_section* poris =
5955 out_sections[index]->find_relaxed_input_section(this, index);
5956 gold_assert(poris != NULL);
5957 output_address = poris->address();
5960 // Get the relocations.
5961 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
5965 // Get the section contents. This does work for the case in which
5966 // we modify the contents of an input section. We need to pass the
5967 // output view under such circumstances.
5968 section_size_type input_view_size = 0;
5969 const unsigned char* input_view =
5970 this->section_contents(index, &input_view_size, false);
5972 relinfo.reloc_shndx = i;
5973 relinfo.data_shndx = index;
5974 unsigned int sh_type = shdr.get_sh_type();
5975 unsigned int reloc_size;
5976 if (sh_type == elfcpp::SHT_REL)
5977 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5979 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5981 Output_section* os = out_sections[index];
5982 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
5983 shdr.get_sh_size() / reloc_size,
5985 output_offset == invalid_address,
5986 input_view, output_address,
5991 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
5992 // after its relocation section, if there is one, is processed for
5993 // relocation stubs. Merging this loop with the one above would have been
5994 // complicated since we would have had to make sure that relocation stub
5995 // scanning is done first.
5996 if (arm_target->fix_cortex_a8())
5998 const unsigned char* p = pshdrs + shdr_size;
5999 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6001 const elfcpp::Shdr<32, big_endian> shdr(p);
6002 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
6005 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
6010 // After we've done the relocations, we release the hash tables,
6011 // since we no longer need them.
6012 this->free_input_to_output_maps();
6015 // Count the local symbols. The ARM backend needs to know if a symbol
6016 // is a THUMB function or not. For global symbols, it is easy because
6017 // the Symbol object keeps the ELF symbol type. For local symbol it is
6018 // harder because we cannot access this information. So we override the
6019 // do_count_local_symbol in parent and scan local symbols to mark
6020 // THUMB functions. This is not the most efficient way but I do not want to
6021 // slow down other ports by calling a per symbol targer hook inside
6022 // Sized_relobj<size, big_endian>::do_count_local_symbols.
6024 template<bool big_endian>
6026 Arm_relobj<big_endian>::do_count_local_symbols(
6027 Stringpool_template<char>* pool,
6028 Stringpool_template<char>* dynpool)
6030 // We need to fix-up the values of any local symbols whose type are
6033 // Ask parent to count the local symbols.
6034 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
6035 const unsigned int loccount = this->local_symbol_count();
6039 // Intialize the thumb function bit-vector.
6040 std::vector<bool> empty_vector(loccount, false);
6041 this->local_symbol_is_thumb_function_.swap(empty_vector);
6043 // Read the symbol table section header.
6044 const unsigned int symtab_shndx = this->symtab_shndx();
6045 elfcpp::Shdr<32, big_endian>
6046 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6047 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6049 // Read the local symbols.
6050 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6051 gold_assert(loccount == symtabshdr.get_sh_info());
6052 off_t locsize = loccount * sym_size;
6053 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6054 locsize, true, true);
6056 // For mapping symbol processing, we need to read the symbol names.
6057 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6058 if (strtab_shndx >= this->shnum())
6060 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6064 elfcpp::Shdr<32, big_endian>
6065 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6066 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6068 this->error(_("symbol table name section has wrong type: %u"),
6069 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6072 const char* pnames =
6073 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6074 strtabshdr.get_sh_size(),
6077 // Loop over the local symbols and mark any local symbols pointing
6078 // to THUMB functions.
6080 // Skip the first dummy symbol.
6082 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
6083 this->local_values();
6084 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6086 elfcpp::Sym<32, big_endian> sym(psyms);
6087 elfcpp::STT st_type = sym.get_st_type();
6088 Symbol_value<32>& lv((*plocal_values)[i]);
6089 Arm_address input_value = lv.input_value();
6091 // Check to see if this is a mapping symbol.
6092 const char* sym_name = pnames + sym.get_st_name();
6093 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6095 unsigned int input_shndx = sym.get_st_shndx();
6097 // Strip of LSB in case this is a THUMB symbol.
6098 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6099 this->mapping_symbols_info_[msp] = sym_name[1];
6102 if (st_type == elfcpp::STT_ARM_TFUNC
6103 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6105 // This is a THUMB function. Mark this and canonicalize the
6106 // symbol value by setting LSB.
6107 this->local_symbol_is_thumb_function_[i] = true;
6108 if ((input_value & 1) == 0)
6109 lv.set_input_value(input_value | 1);
6114 // Relocate sections.
6115 template<bool big_endian>
6117 Arm_relobj<big_endian>::do_relocate_sections(
6118 const Symbol_table* symtab,
6119 const Layout* layout,
6120 const unsigned char* pshdrs,
6121 typename Sized_relobj<32, big_endian>::Views* pviews)
6123 // Call parent to relocate sections.
6124 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
6127 // We do not generate stubs if doing a relocatable link.
6128 if (parameters->options().relocatable())
6131 // Relocate stub tables.
6132 unsigned int shnum = this->shnum();
6134 Target_arm<big_endian>* arm_target =
6135 Target_arm<big_endian>::default_target();
6137 Relocate_info<32, big_endian> relinfo;
6138 relinfo.symtab = symtab;
6139 relinfo.layout = layout;
6140 relinfo.object = this;
6142 for (unsigned int i = 1; i < shnum; ++i)
6144 Arm_input_section<big_endian>* arm_input_section =
6145 arm_target->find_arm_input_section(this, i);
6147 if (arm_input_section != NULL
6148 && arm_input_section->is_stub_table_owner()
6149 && !arm_input_section->stub_table()->empty())
6151 // We cannot discard a section if it owns a stub table.
6152 Output_section* os = this->output_section(i);
6153 gold_assert(os != NULL);
6155 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6156 relinfo.reloc_shdr = NULL;
6157 relinfo.data_shndx = i;
6158 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6160 gold_assert((*pviews)[i].view != NULL);
6162 // We are passed the output section view. Adjust it to cover the
6164 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6165 gold_assert((stub_table->address() >= (*pviews)[i].address)
6166 && ((stub_table->address() + stub_table->data_size())
6167 <= (*pviews)[i].address + (*pviews)[i].view_size));
6169 off_t offset = stub_table->address() - (*pviews)[i].address;
6170 unsigned char* view = (*pviews)[i].view + offset;
6171 Arm_address address = stub_table->address();
6172 section_size_type view_size = stub_table->data_size();
6174 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6178 // Apply Cortex A8 workaround if applicable.
6179 if (this->section_has_cortex_a8_workaround(i))
6181 unsigned char* view = (*pviews)[i].view;
6182 Arm_address view_address = (*pviews)[i].address;
6183 section_size_type view_size = (*pviews)[i].view_size;
6184 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6186 // Adjust view to cover section.
6187 Output_section* os = this->output_section(i);
6188 gold_assert(os != NULL);
6189 Arm_address section_address =
6190 this->simple_input_section_output_address(i, os);
6191 uint64_t section_size = this->section_size(i);
6193 gold_assert(section_address >= view_address
6194 && ((section_address + section_size)
6195 <= (view_address + view_size)));
6197 unsigned char* section_view = view + (section_address - view_address);
6199 // Apply the Cortex-A8 workaround to the output address range
6200 // corresponding to this input section.
6201 stub_table->apply_cortex_a8_workaround_to_address_range(
6210 // Find the linked text section of an EXIDX section by looking the the first
6211 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6212 // must be linked to to its associated code section via the sh_link field of
6213 // its section header. However, some tools are broken and the link is not
6214 // always set. LD just drops such an EXIDX section silently, causing the
6215 // associated code not unwindabled. Here we try a little bit harder to
6216 // discover the linked code section.
6218 // PSHDR points to the section header of a relocation section of an EXIDX
6219 // section. If we can find a linked text section, return true and
6220 // store the text section index in the location PSHNDX. Otherwise
6223 template<bool big_endian>
6225 Arm_relobj<big_endian>::find_linked_text_section(
6226 const unsigned char* pshdr,
6227 const unsigned char* psyms,
6228 unsigned int* pshndx)
6230 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6232 // If there is no relocation, we cannot find the linked text section.
6234 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6235 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6237 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6238 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6240 // Get the relocations.
6241 const unsigned char* prelocs =
6242 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6244 // Find the REL31 relocation for the first word of the first EXIDX entry.
6245 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6247 Arm_address r_offset;
6248 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6249 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6251 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6252 r_info = reloc.get_r_info();
6253 r_offset = reloc.get_r_offset();
6257 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6258 r_info = reloc.get_r_info();
6259 r_offset = reloc.get_r_offset();
6262 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6263 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6266 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6268 || r_sym >= this->local_symbol_count()
6272 // This is the relocation for the first word of the first EXIDX entry.
6273 // We expect to see a local section symbol.
6274 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6275 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6276 if (sym.get_st_type() == elfcpp::STT_SECTION)
6278 *pshndx = this->adjust_shndx(sym.get_st_shndx());
6288 // Make an EXIDX input section object for an EXIDX section whose index is
6289 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6290 // is the section index of the linked text section.
6292 template<bool big_endian>
6294 Arm_relobj<big_endian>::make_exidx_input_section(
6296 const elfcpp::Shdr<32, big_endian>& shdr,
6297 unsigned int text_shndx)
6299 // Issue an error and ignore this EXIDX section if it points to a text
6300 // section already has an EXIDX section.
6301 if (this->exidx_section_map_[text_shndx] != NULL)
6303 gold_error(_("EXIDX sections %u and %u both link to text section %u "
6305 shndx, this->exidx_section_map_[text_shndx]->shndx(),
6306 text_shndx, this->name().c_str());
6310 // Create an Arm_exidx_input_section object for this EXIDX section.
6311 Arm_exidx_input_section* exidx_input_section =
6312 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6313 shdr.get_sh_addralign());
6314 this->exidx_section_map_[text_shndx] = exidx_input_section;
6316 // Also map the EXIDX section index to this.
6317 gold_assert(this->exidx_section_map_[shndx] == NULL);
6318 this->exidx_section_map_[shndx] = exidx_input_section;
6321 // Read the symbol information.
6323 template<bool big_endian>
6325 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6327 // Call parent class to read symbol information.
6328 Sized_relobj<32, big_endian>::do_read_symbols(sd);
6330 // Read processor-specific flags in ELF file header.
6331 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6332 elfcpp::Elf_sizes<32>::ehdr_size,
6334 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6335 this->processor_specific_flags_ = ehdr.get_e_flags();
6337 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6339 std::vector<unsigned int> deferred_exidx_sections;
6340 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6341 const unsigned char* pshdrs = sd->section_headers->data();
6342 const unsigned char *ps = pshdrs + shdr_size;
6343 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6345 elfcpp::Shdr<32, big_endian> shdr(ps);
6346 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6348 gold_assert(this->attributes_section_data_ == NULL);
6349 section_offset_type section_offset = shdr.get_sh_offset();
6350 section_size_type section_size =
6351 convert_to_section_size_type(shdr.get_sh_size());
6352 File_view* view = this->get_lasting_view(section_offset,
6353 section_size, true, false);
6354 this->attributes_section_data_ =
6355 new Attributes_section_data(view->data(), section_size);
6357 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6359 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6360 if (text_shndx >= this->shnum())
6361 gold_error(_("EXIDX section %u linked to invalid section %u"),
6363 else if (text_shndx == elfcpp::SHN_UNDEF)
6364 deferred_exidx_sections.push_back(i);
6366 this->make_exidx_input_section(i, shdr, text_shndx);
6370 // Some tools are broken and they do not set the link of EXIDX sections.
6371 // We look at the first relocation to figure out the linked sections.
6372 if (!deferred_exidx_sections.empty())
6374 // We need to go over the section headers again to find the mapping
6375 // from sections being relocated to their relocation sections. This is
6376 // a bit inefficient as we could do that in the loop above. However,
6377 // we do not expect any deferred EXIDX sections normally. So we do not
6378 // want to slow down the most common path.
6379 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6380 Reloc_map reloc_map;
6381 ps = pshdrs + shdr_size;
6382 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6384 elfcpp::Shdr<32, big_endian> shdr(ps);
6385 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6386 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6388 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6389 if (info_shndx >= this->shnum())
6390 gold_error(_("relocation section %u has invalid info %u"),
6392 Reloc_map::value_type value(info_shndx, i);
6393 std::pair<Reloc_map::iterator, bool> result =
6394 reloc_map.insert(value);
6396 gold_error(_("section %u has multiple relocation sections "
6398 info_shndx, i, reloc_map[info_shndx]);
6402 // Read the symbol table section header.
6403 const unsigned int symtab_shndx = this->symtab_shndx();
6404 elfcpp::Shdr<32, big_endian>
6405 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6406 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6408 // Read the local symbols.
6409 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6410 const unsigned int loccount = this->local_symbol_count();
6411 gold_assert(loccount == symtabshdr.get_sh_info());
6412 off_t locsize = loccount * sym_size;
6413 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6414 locsize, true, true);
6416 // Process the deferred EXIDX sections.
6417 for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6419 unsigned int shndx = deferred_exidx_sections[i];
6420 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6421 unsigned int text_shndx;
6422 Reloc_map::const_iterator it = reloc_map.find(shndx);
6423 if (it != reloc_map.end()
6424 && find_linked_text_section(pshdrs + it->second * shdr_size,
6425 psyms, &text_shndx))
6426 this->make_exidx_input_section(shndx, shdr, text_shndx);
6428 gold_error(_("EXIDX section %u has no linked text section."),
6434 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6435 // sections for unwinding. These sections are referenced implicitly by
6436 // text sections linked in the section headers. If we ignore these implict
6437 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6438 // will be garbage-collected incorrectly. Hence we override the same function
6439 // in the base class to handle these implicit references.
6441 template<bool big_endian>
6443 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6445 Read_relocs_data* rd)
6447 // First, call base class method to process relocations in this object.
6448 Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6450 // If --gc-sections is not specified, there is nothing more to do.
6451 // This happens when --icf is used but --gc-sections is not.
6452 if (!parameters->options().gc_sections())
6455 unsigned int shnum = this->shnum();
6456 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6457 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6461 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6462 // to these from the linked text sections.
6463 const unsigned char* ps = pshdrs + shdr_size;
6464 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6466 elfcpp::Shdr<32, big_endian> shdr(ps);
6467 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6469 // Found an .ARM.exidx section, add it to the set of reachable
6470 // sections from its linked text section.
6471 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6472 symtab->gc()->add_reference(this, text_shndx, this, i);
6477 // Update output local symbol count. Owing to EXIDX entry merging, some local
6478 // symbols will be removed in output. Adjust output local symbol count
6479 // accordingly. We can only changed the static output local symbol count. It
6480 // is too late to change the dynamic symbols.
6482 template<bool big_endian>
6484 Arm_relobj<big_endian>::update_output_local_symbol_count()
6486 // Caller should check that this needs updating. We want caller checking
6487 // because output_local_symbol_count_needs_update() is most likely inlined.
6488 gold_assert(this->output_local_symbol_count_needs_update_);
6490 gold_assert(this->symtab_shndx() != -1U);
6491 if (this->symtab_shndx() == 0)
6493 // This object has no symbols. Weird but legal.
6497 // Read the symbol table section header.
6498 const unsigned int symtab_shndx = this->symtab_shndx();
6499 elfcpp::Shdr<32, big_endian>
6500 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6501 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6503 // Read the local symbols.
6504 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6505 const unsigned int loccount = this->local_symbol_count();
6506 gold_assert(loccount == symtabshdr.get_sh_info());
6507 off_t locsize = loccount * sym_size;
6508 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6509 locsize, true, true);
6511 // Loop over the local symbols.
6513 typedef typename Sized_relobj<32, big_endian>::Output_sections
6515 const Output_sections& out_sections(this->output_sections());
6516 unsigned int shnum = this->shnum();
6517 unsigned int count = 0;
6518 // Skip the first, dummy, symbol.
6520 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6522 elfcpp::Sym<32, big_endian> sym(psyms);
6524 Symbol_value<32>& lv((*this->local_values())[i]);
6526 // This local symbol was already discarded by do_count_local_symbols.
6527 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6531 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6536 Output_section* os = out_sections[shndx];
6538 // This local symbol no longer has an output section. Discard it.
6541 lv.set_no_output_symtab_entry();
6545 // Currently we only discard parts of EXIDX input sections.
6546 // We explicitly check for a merged EXIDX input section to avoid
6547 // calling Output_section_data::output_offset unless necessary.
6548 if ((this->get_output_section_offset(shndx) == invalid_address)
6549 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6551 section_offset_type output_offset =
6552 os->output_offset(this, shndx, lv.input_value());
6553 if (output_offset == -1)
6555 // This symbol is defined in a part of an EXIDX input section
6556 // that is discarded due to entry merging.
6557 lv.set_no_output_symtab_entry();
6566 this->set_output_local_symbol_count(count);
6567 this->output_local_symbol_count_needs_update_ = false;
6570 // Arm_dynobj methods.
6572 // Read the symbol information.
6574 template<bool big_endian>
6576 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6578 // Call parent class to read symbol information.
6579 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6581 // Read processor-specific flags in ELF file header.
6582 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6583 elfcpp::Elf_sizes<32>::ehdr_size,
6585 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6586 this->processor_specific_flags_ = ehdr.get_e_flags();
6588 // Read the attributes section if there is one.
6589 // We read from the end because gas seems to put it near the end of
6590 // the section headers.
6591 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6592 const unsigned char *ps =
6593 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6594 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6596 elfcpp::Shdr<32, big_endian> shdr(ps);
6597 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6599 section_offset_type section_offset = shdr.get_sh_offset();
6600 section_size_type section_size =
6601 convert_to_section_size_type(shdr.get_sh_size());
6602 File_view* view = this->get_lasting_view(section_offset,
6603 section_size, true, false);
6604 this->attributes_section_data_ =
6605 new Attributes_section_data(view->data(), section_size);
6611 // Stub_addend_reader methods.
6613 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6615 template<bool big_endian>
6616 elfcpp::Elf_types<32>::Elf_Swxword
6617 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
6618 unsigned int r_type,
6619 const unsigned char* view,
6620 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
6622 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
6626 case elfcpp::R_ARM_CALL:
6627 case elfcpp::R_ARM_JUMP24:
6628 case elfcpp::R_ARM_PLT32:
6630 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6631 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6632 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
6633 return utils::sign_extend<26>(val << 2);
6636 case elfcpp::R_ARM_THM_CALL:
6637 case elfcpp::R_ARM_THM_JUMP24:
6638 case elfcpp::R_ARM_THM_XPC22:
6640 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6641 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6642 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6643 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6644 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
6647 case elfcpp::R_ARM_THM_JUMP19:
6649 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6650 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6651 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6652 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6653 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
6661 // Arm_output_data_got methods.
6663 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
6664 // The first one is initialized to be 1, which is the module index for
6665 // the main executable and the second one 0. A reloc of the type
6666 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
6667 // be applied by gold. GSYM is a global symbol.
6669 template<bool big_endian>
6671 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6672 unsigned int got_type,
6675 if (gsym->has_got_offset(got_type))
6678 // We are doing a static link. Just mark it as belong to module 1,
6680 unsigned int got_offset = this->add_constant(1);
6681 gsym->set_got_offset(got_type, got_offset);
6682 got_offset = this->add_constant(0);
6683 this->static_relocs_.push_back(Static_reloc(got_offset,
6684 elfcpp::R_ARM_TLS_DTPOFF32,
6688 // Same as the above but for a local symbol.
6690 template<bool big_endian>
6692 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6693 unsigned int got_type,
6694 Sized_relobj<32, big_endian>* object,
6697 if (object->local_has_got_offset(index, got_type))
6700 // We are doing a static link. Just mark it as belong to module 1,
6702 unsigned int got_offset = this->add_constant(1);
6703 object->set_local_got_offset(index, got_type, got_offset);
6704 got_offset = this->add_constant(0);
6705 this->static_relocs_.push_back(Static_reloc(got_offset,
6706 elfcpp::R_ARM_TLS_DTPOFF32,
6710 template<bool big_endian>
6712 Arm_output_data_got<big_endian>::do_write(Output_file* of)
6714 // Call parent to write out GOT.
6715 Output_data_got<32, big_endian>::do_write(of);
6717 // We are done if there is no fix up.
6718 if (this->static_relocs_.empty())
6721 gold_assert(parameters->doing_static_link());
6723 const off_t offset = this->offset();
6724 const section_size_type oview_size =
6725 convert_to_section_size_type(this->data_size());
6726 unsigned char* const oview = of->get_output_view(offset, oview_size);
6728 Output_segment* tls_segment = this->layout_->tls_segment();
6729 gold_assert(tls_segment != NULL);
6731 // The thread pointer $tp points to the TCB, which is followed by the
6732 // TLS. So we need to adjust $tp relative addressing by this amount.
6733 Arm_address aligned_tcb_size =
6734 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
6736 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
6738 Static_reloc& reloc(this->static_relocs_[i]);
6741 if (!reloc.symbol_is_global())
6743 Sized_relobj<32, big_endian>* object = reloc.relobj();
6744 const Symbol_value<32>* psymval =
6745 reloc.relobj()->local_symbol(reloc.index());
6747 // We are doing static linking. Issue an error and skip this
6748 // relocation if the symbol is undefined or in a discarded_section.
6750 unsigned int shndx = psymval->input_shndx(&is_ordinary);
6751 if ((shndx == elfcpp::SHN_UNDEF)
6753 && shndx != elfcpp::SHN_UNDEF
6754 && !object->is_section_included(shndx)
6755 && !this->symbol_table_->is_section_folded(object, shndx)))
6757 gold_error(_("undefined or discarded local symbol %u from "
6758 " object %s in GOT"),
6759 reloc.index(), reloc.relobj()->name().c_str());
6763 value = psymval->value(object, 0);
6767 const Symbol* gsym = reloc.symbol();
6768 gold_assert(gsym != NULL);
6769 if (gsym->is_forwarder())
6770 gsym = this->symbol_table_->resolve_forwards(gsym);
6772 // We are doing static linking. Issue an error and skip this
6773 // relocation if the symbol is undefined or in a discarded_section
6774 // unless it is a weakly_undefined symbol.
6775 if ((gsym->is_defined_in_discarded_section()
6776 || gsym->is_undefined())
6777 && !gsym->is_weak_undefined())
6779 gold_error(_("undefined or discarded symbol %s in GOT"),
6784 if (!gsym->is_weak_undefined())
6786 const Sized_symbol<32>* sym =
6787 static_cast<const Sized_symbol<32>*>(gsym);
6788 value = sym->value();
6794 unsigned got_offset = reloc.got_offset();
6795 gold_assert(got_offset < oview_size);
6797 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6798 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
6800 switch (reloc.r_type())
6802 case elfcpp::R_ARM_TLS_DTPOFF32:
6805 case elfcpp::R_ARM_TLS_TPOFF32:
6806 x = value + aligned_tcb_size;
6811 elfcpp::Swap<32, big_endian>::writeval(wv, x);
6814 of->write_output_view(offset, oview_size, oview);
6817 // A class to handle the PLT data.
6819 template<bool big_endian>
6820 class Output_data_plt_arm : public Output_section_data
6823 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
6826 Output_data_plt_arm(Layout*, Output_data_space*);
6828 // Add an entry to the PLT.
6830 add_entry(Symbol* gsym);
6832 // Return the .rel.plt section data.
6833 const Reloc_section*
6835 { return this->rel_; }
6839 do_adjust_output_section(Output_section* os);
6841 // Write to a map file.
6843 do_print_to_mapfile(Mapfile* mapfile) const
6844 { mapfile->print_output_data(this, _("** PLT")); }
6847 // Template for the first PLT entry.
6848 static const uint32_t first_plt_entry[5];
6850 // Template for subsequent PLT entries.
6851 static const uint32_t plt_entry[3];
6853 // Set the final size.
6855 set_final_data_size()
6857 this->set_data_size(sizeof(first_plt_entry)
6858 + this->count_ * sizeof(plt_entry));
6861 // Write out the PLT data.
6863 do_write(Output_file*);
6865 // The reloc section.
6866 Reloc_section* rel_;
6867 // The .got.plt section.
6868 Output_data_space* got_plt_;
6869 // The number of PLT entries.
6870 unsigned int count_;
6873 // Create the PLT section. The ordinary .got section is an argument,
6874 // since we need to refer to the start. We also create our own .got
6875 // section just for PLT entries.
6877 template<bool big_endian>
6878 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
6879 Output_data_space* got_plt)
6880 : Output_section_data(4), got_plt_(got_plt), count_(0)
6882 this->rel_ = new Reloc_section(false);
6883 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
6884 elfcpp::SHF_ALLOC, this->rel_, true, false,
6888 template<bool big_endian>
6890 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
6895 // Add an entry to the PLT.
6897 template<bool big_endian>
6899 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
6901 gold_assert(!gsym->has_plt_offset());
6903 // Note that when setting the PLT offset we skip the initial
6904 // reserved PLT entry.
6905 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
6906 + sizeof(first_plt_entry));
6910 section_offset_type got_offset = this->got_plt_->current_data_size();
6912 // Every PLT entry needs a GOT entry which points back to the PLT
6913 // entry (this will be changed by the dynamic linker, normally
6914 // lazily when the function is called).
6915 this->got_plt_->set_current_data_size(got_offset + 4);
6917 // Every PLT entry needs a reloc.
6918 gsym->set_needs_dynsym_entry();
6919 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
6922 // Note that we don't need to save the symbol. The contents of the
6923 // PLT are independent of which symbols are used. The symbols only
6924 // appear in the relocations.
6928 // FIXME: This is not very flexible. Right now this has only been tested
6929 // on armv5te. If we are to support additional architecture features like
6930 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
6932 // The first entry in the PLT.
6933 template<bool big_endian>
6934 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
6936 0xe52de004, // str lr, [sp, #-4]!
6937 0xe59fe004, // ldr lr, [pc, #4]
6938 0xe08fe00e, // add lr, pc, lr
6939 0xe5bef008, // ldr pc, [lr, #8]!
6940 0x00000000, // &GOT[0] - .
6943 // Subsequent entries in the PLT.
6945 template<bool big_endian>
6946 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
6948 0xe28fc600, // add ip, pc, #0xNN00000
6949 0xe28cca00, // add ip, ip, #0xNN000
6950 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
6953 // Write out the PLT. This uses the hand-coded instructions above,
6954 // and adjusts them as needed. This is all specified by the arm ELF
6955 // Processor Supplement.
6957 template<bool big_endian>
6959 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
6961 const off_t offset = this->offset();
6962 const section_size_type oview_size =
6963 convert_to_section_size_type(this->data_size());
6964 unsigned char* const oview = of->get_output_view(offset, oview_size);
6966 const off_t got_file_offset = this->got_plt_->offset();
6967 const section_size_type got_size =
6968 convert_to_section_size_type(this->got_plt_->data_size());
6969 unsigned char* const got_view = of->get_output_view(got_file_offset,
6971 unsigned char* pov = oview;
6973 Arm_address plt_address = this->address();
6974 Arm_address got_address = this->got_plt_->address();
6976 // Write first PLT entry. All but the last word are constants.
6977 const size_t num_first_plt_words = (sizeof(first_plt_entry)
6978 / sizeof(plt_entry[0]));
6979 for (size_t i = 0; i < num_first_plt_words - 1; i++)
6980 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
6981 // Last word in first PLT entry is &GOT[0] - .
6982 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
6983 got_address - (plt_address + 16));
6984 pov += sizeof(first_plt_entry);
6986 unsigned char* got_pov = got_view;
6988 memset(got_pov, 0, 12);
6991 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
6992 unsigned int plt_offset = sizeof(first_plt_entry);
6993 unsigned int plt_rel_offset = 0;
6994 unsigned int got_offset = 12;
6995 const unsigned int count = this->count_;
6996 for (unsigned int i = 0;
6999 pov += sizeof(plt_entry),
7001 plt_offset += sizeof(plt_entry),
7002 plt_rel_offset += rel_size,
7005 // Set and adjust the PLT entry itself.
7006 int32_t offset = ((got_address + got_offset)
7007 - (plt_address + plt_offset + 8));
7009 gold_assert(offset >= 0 && offset < 0x0fffffff);
7010 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
7011 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
7012 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
7013 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
7014 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
7015 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7017 // Set the entry in the GOT.
7018 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7021 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7022 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7024 of->write_output_view(offset, oview_size, oview);
7025 of->write_output_view(got_file_offset, got_size, got_view);
7028 // Create a PLT entry for a global symbol.
7030 template<bool big_endian>
7032 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7035 if (gsym->has_plt_offset())
7038 if (this->plt_ == NULL)
7040 // Create the GOT sections first.
7041 this->got_section(symtab, layout);
7043 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
7044 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7046 | elfcpp::SHF_EXECINSTR),
7047 this->plt_, false, false, false, false);
7049 this->plt_->add_entry(gsym);
7052 // Get the section to use for TLS_DESC relocations.
7054 template<bool big_endian>
7055 typename Target_arm<big_endian>::Reloc_section*
7056 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7058 return this->plt_section()->rel_tls_desc(layout);
7061 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7063 template<bool big_endian>
7065 Target_arm<big_endian>::define_tls_base_symbol(
7066 Symbol_table* symtab,
7069 if (this->tls_base_symbol_defined_)
7072 Output_segment* tls_segment = layout->tls_segment();
7073 if (tls_segment != NULL)
7075 bool is_exec = parameters->options().output_is_executable();
7076 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7077 Symbol_table::PREDEFINED,
7081 elfcpp::STV_HIDDEN, 0,
7083 ? Symbol::SEGMENT_END
7084 : Symbol::SEGMENT_START),
7087 this->tls_base_symbol_defined_ = true;
7090 // Create a GOT entry for the TLS module index.
7092 template<bool big_endian>
7094 Target_arm<big_endian>::got_mod_index_entry(
7095 Symbol_table* symtab,
7097 Sized_relobj<32, big_endian>* object)
7099 if (this->got_mod_index_offset_ == -1U)
7101 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7102 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7103 unsigned int got_offset;
7104 if (!parameters->doing_static_link())
7106 got_offset = got->add_constant(0);
7107 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7108 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7113 // We are doing a static link. Just mark it as belong to module 1,
7115 got_offset = got->add_constant(1);
7118 got->add_constant(0);
7119 this->got_mod_index_offset_ = got_offset;
7121 return this->got_mod_index_offset_;
7124 // Optimize the TLS relocation type based on what we know about the
7125 // symbol. IS_FINAL is true if the final address of this symbol is
7126 // known at link time.
7128 template<bool big_endian>
7129 tls::Tls_optimization
7130 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7132 // FIXME: Currently we do not do any TLS optimization.
7133 return tls::TLSOPT_NONE;
7136 // Report an unsupported relocation against a local symbol.
7138 template<bool big_endian>
7140 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7141 Sized_relobj<32, big_endian>* object,
7142 unsigned int r_type)
7144 gold_error(_("%s: unsupported reloc %u against local symbol"),
7145 object->name().c_str(), r_type);
7148 // We are about to emit a dynamic relocation of type R_TYPE. If the
7149 // dynamic linker does not support it, issue an error. The GNU linker
7150 // only issues a non-PIC error for an allocated read-only section.
7151 // Here we know the section is allocated, but we don't know that it is
7152 // read-only. But we check for all the relocation types which the
7153 // glibc dynamic linker supports, so it seems appropriate to issue an
7154 // error even if the section is not read-only.
7156 template<bool big_endian>
7158 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7159 unsigned int r_type)
7163 // These are the relocation types supported by glibc for ARM.
7164 case elfcpp::R_ARM_RELATIVE:
7165 case elfcpp::R_ARM_COPY:
7166 case elfcpp::R_ARM_GLOB_DAT:
7167 case elfcpp::R_ARM_JUMP_SLOT:
7168 case elfcpp::R_ARM_ABS32:
7169 case elfcpp::R_ARM_ABS32_NOI:
7170 case elfcpp::R_ARM_PC24:
7171 // FIXME: The following 3 types are not supported by Android's dynamic
7173 case elfcpp::R_ARM_TLS_DTPMOD32:
7174 case elfcpp::R_ARM_TLS_DTPOFF32:
7175 case elfcpp::R_ARM_TLS_TPOFF32:
7180 // This prevents us from issuing more than one error per reloc
7181 // section. But we can still wind up issuing more than one
7182 // error per object file.
7183 if (this->issued_non_pic_error_)
7185 const Arm_reloc_property* reloc_property =
7186 arm_reloc_property_table->get_reloc_property(r_type);
7187 gold_assert(reloc_property != NULL);
7188 object->error(_("requires unsupported dynamic reloc %s; "
7189 "recompile with -fPIC"),
7190 reloc_property->name().c_str());
7191 this->issued_non_pic_error_ = true;
7195 case elfcpp::R_ARM_NONE:
7200 // Scan a relocation for a local symbol.
7201 // FIXME: This only handles a subset of relocation types used by Android
7202 // on ARM v5te devices.
7204 template<bool big_endian>
7206 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7209 Sized_relobj<32, big_endian>* object,
7210 unsigned int data_shndx,
7211 Output_section* output_section,
7212 const elfcpp::Rel<32, big_endian>& reloc,
7213 unsigned int r_type,
7214 const elfcpp::Sym<32, big_endian>& lsym)
7216 r_type = get_real_reloc_type(r_type);
7219 case elfcpp::R_ARM_NONE:
7220 case elfcpp::R_ARM_V4BX:
7221 case elfcpp::R_ARM_GNU_VTENTRY:
7222 case elfcpp::R_ARM_GNU_VTINHERIT:
7225 case elfcpp::R_ARM_ABS32:
7226 case elfcpp::R_ARM_ABS32_NOI:
7227 // If building a shared library (or a position-independent
7228 // executable), we need to create a dynamic relocation for
7229 // this location. The relocation applied at link time will
7230 // apply the link-time value, so we flag the location with
7231 // an R_ARM_RELATIVE relocation so the dynamic loader can
7232 // relocate it easily.
7233 if (parameters->options().output_is_position_independent())
7235 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7236 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7237 // If we are to add more other reloc types than R_ARM_ABS32,
7238 // we need to add check_non_pic(object, r_type) here.
7239 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7240 output_section, data_shndx,
7241 reloc.get_r_offset());
7245 case elfcpp::R_ARM_ABS16:
7246 case elfcpp::R_ARM_ABS12:
7247 case elfcpp::R_ARM_THM_ABS5:
7248 case elfcpp::R_ARM_ABS8:
7249 case elfcpp::R_ARM_BASE_ABS:
7250 case elfcpp::R_ARM_MOVW_ABS_NC:
7251 case elfcpp::R_ARM_MOVT_ABS:
7252 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7253 case elfcpp::R_ARM_THM_MOVT_ABS:
7254 // If building a shared library (or a position-independent
7255 // executable), we need to create a dynamic relocation for
7256 // this location. Because the addend needs to remain in the
7257 // data section, we need to be careful not to apply this
7258 // relocation statically.
7259 if (parameters->options().output_is_position_independent())
7261 check_non_pic(object, r_type);
7262 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7263 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7264 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7265 rel_dyn->add_local(object, r_sym, r_type, output_section,
7266 data_shndx, reloc.get_r_offset());
7269 gold_assert(lsym.get_st_value() == 0);
7270 unsigned int shndx = lsym.get_st_shndx();
7272 shndx = object->adjust_sym_shndx(r_sym, shndx,
7275 object->error(_("section symbol %u has bad shndx %u"),
7278 rel_dyn->add_local_section(object, shndx,
7279 r_type, output_section,
7280 data_shndx, reloc.get_r_offset());
7285 case elfcpp::R_ARM_PC24:
7286 case elfcpp::R_ARM_REL32:
7287 case elfcpp::R_ARM_LDR_PC_G0:
7288 case elfcpp::R_ARM_SBREL32:
7289 case elfcpp::R_ARM_THM_CALL:
7290 case elfcpp::R_ARM_THM_PC8:
7291 case elfcpp::R_ARM_BASE_PREL:
7292 case elfcpp::R_ARM_PLT32:
7293 case elfcpp::R_ARM_CALL:
7294 case elfcpp::R_ARM_JUMP24:
7295 case elfcpp::R_ARM_THM_JUMP24:
7296 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7297 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7298 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7299 case elfcpp::R_ARM_SBREL31:
7300 case elfcpp::R_ARM_PREL31:
7301 case elfcpp::R_ARM_MOVW_PREL_NC:
7302 case elfcpp::R_ARM_MOVT_PREL:
7303 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7304 case elfcpp::R_ARM_THM_MOVT_PREL:
7305 case elfcpp::R_ARM_THM_JUMP19:
7306 case elfcpp::R_ARM_THM_JUMP6:
7307 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7308 case elfcpp::R_ARM_THM_PC12:
7309 case elfcpp::R_ARM_REL32_NOI:
7310 case elfcpp::R_ARM_ALU_PC_G0_NC:
7311 case elfcpp::R_ARM_ALU_PC_G0:
7312 case elfcpp::R_ARM_ALU_PC_G1_NC:
7313 case elfcpp::R_ARM_ALU_PC_G1:
7314 case elfcpp::R_ARM_ALU_PC_G2:
7315 case elfcpp::R_ARM_LDR_PC_G1:
7316 case elfcpp::R_ARM_LDR_PC_G2:
7317 case elfcpp::R_ARM_LDRS_PC_G0:
7318 case elfcpp::R_ARM_LDRS_PC_G1:
7319 case elfcpp::R_ARM_LDRS_PC_G2:
7320 case elfcpp::R_ARM_LDC_PC_G0:
7321 case elfcpp::R_ARM_LDC_PC_G1:
7322 case elfcpp::R_ARM_LDC_PC_G2:
7323 case elfcpp::R_ARM_ALU_SB_G0_NC:
7324 case elfcpp::R_ARM_ALU_SB_G0:
7325 case elfcpp::R_ARM_ALU_SB_G1_NC:
7326 case elfcpp::R_ARM_ALU_SB_G1:
7327 case elfcpp::R_ARM_ALU_SB_G2:
7328 case elfcpp::R_ARM_LDR_SB_G0:
7329 case elfcpp::R_ARM_LDR_SB_G1:
7330 case elfcpp::R_ARM_LDR_SB_G2:
7331 case elfcpp::R_ARM_LDRS_SB_G0:
7332 case elfcpp::R_ARM_LDRS_SB_G1:
7333 case elfcpp::R_ARM_LDRS_SB_G2:
7334 case elfcpp::R_ARM_LDC_SB_G0:
7335 case elfcpp::R_ARM_LDC_SB_G1:
7336 case elfcpp::R_ARM_LDC_SB_G2:
7337 case elfcpp::R_ARM_MOVW_BREL_NC:
7338 case elfcpp::R_ARM_MOVT_BREL:
7339 case elfcpp::R_ARM_MOVW_BREL:
7340 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7341 case elfcpp::R_ARM_THM_MOVT_BREL:
7342 case elfcpp::R_ARM_THM_MOVW_BREL:
7343 case elfcpp::R_ARM_THM_JUMP11:
7344 case elfcpp::R_ARM_THM_JUMP8:
7345 // We don't need to do anything for a relative addressing relocation
7346 // against a local symbol if it does not reference the GOT.
7349 case elfcpp::R_ARM_GOTOFF32:
7350 case elfcpp::R_ARM_GOTOFF12:
7351 // We need a GOT section:
7352 target->got_section(symtab, layout);
7355 case elfcpp::R_ARM_GOT_BREL:
7356 case elfcpp::R_ARM_GOT_PREL:
7358 // The symbol requires a GOT entry.
7359 Arm_output_data_got<big_endian>* got =
7360 target->got_section(symtab, layout);
7361 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7362 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
7364 // If we are generating a shared object, we need to add a
7365 // dynamic RELATIVE relocation for this symbol's GOT entry.
7366 if (parameters->options().output_is_position_independent())
7368 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7369 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7370 rel_dyn->add_local_relative(
7371 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
7372 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
7378 case elfcpp::R_ARM_TARGET1:
7379 case elfcpp::R_ARM_TARGET2:
7380 // This should have been mapped to another type already.
7382 case elfcpp::R_ARM_COPY:
7383 case elfcpp::R_ARM_GLOB_DAT:
7384 case elfcpp::R_ARM_JUMP_SLOT:
7385 case elfcpp::R_ARM_RELATIVE:
7386 // These are relocations which should only be seen by the
7387 // dynamic linker, and should never be seen here.
7388 gold_error(_("%s: unexpected reloc %u in object file"),
7389 object->name().c_str(), r_type);
7393 // These are initial TLS relocs, which are expected when
7395 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7396 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7397 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7398 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7399 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7401 bool output_is_shared = parameters->options().shared();
7402 const tls::Tls_optimization optimized_type
7403 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
7407 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7408 if (optimized_type == tls::TLSOPT_NONE)
7410 // Create a pair of GOT entries for the module index and
7411 // dtv-relative offset.
7412 Arm_output_data_got<big_endian>* got
7413 = target->got_section(symtab, layout);
7414 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7415 unsigned int shndx = lsym.get_st_shndx();
7417 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
7420 object->error(_("local symbol %u has bad shndx %u"),
7425 if (!parameters->doing_static_link())
7426 got->add_local_pair_with_rel(object, r_sym, shndx,
7428 target->rel_dyn_section(layout),
7429 elfcpp::R_ARM_TLS_DTPMOD32, 0);
7431 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
7435 // FIXME: TLS optimization not supported yet.
7439 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7440 if (optimized_type == tls::TLSOPT_NONE)
7442 // Create a GOT entry for the module index.
7443 target->got_mod_index_entry(symtab, layout, object);
7446 // FIXME: TLS optimization not supported yet.
7450 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7453 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7454 layout->set_has_static_tls();
7455 if (optimized_type == tls::TLSOPT_NONE)
7457 // Create a GOT entry for the tp-relative offset.
7458 Arm_output_data_got<big_endian>* got
7459 = target->got_section(symtab, layout);
7460 unsigned int r_sym =
7461 elfcpp::elf_r_sym<32>(reloc.get_r_info());
7462 if (!parameters->doing_static_link())
7463 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
7464 target->rel_dyn_section(layout),
7465 elfcpp::R_ARM_TLS_TPOFF32);
7466 else if (!object->local_has_got_offset(r_sym,
7467 GOT_TYPE_TLS_OFFSET))
7469 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
7470 unsigned int got_offset =
7471 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
7472 got->add_static_reloc(got_offset,
7473 elfcpp::R_ARM_TLS_TPOFF32, object,
7478 // FIXME: TLS optimization not supported yet.
7482 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7483 layout->set_has_static_tls();
7484 if (output_is_shared)
7486 // We need to create a dynamic relocation.
7487 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7488 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7489 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7490 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
7491 output_section, data_shndx,
7492 reloc.get_r_offset());
7503 unsupported_reloc_local(object, r_type);
7508 // Report an unsupported relocation against a global symbol.
7510 template<bool big_endian>
7512 Target_arm<big_endian>::Scan::unsupported_reloc_global(
7513 Sized_relobj<32, big_endian>* object,
7514 unsigned int r_type,
7517 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
7518 object->name().c_str(), r_type, gsym->demangled_name().c_str());
7521 // Scan a relocation for a global symbol.
7523 template<bool big_endian>
7525 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
7528 Sized_relobj<32, big_endian>* object,
7529 unsigned int data_shndx,
7530 Output_section* output_section,
7531 const elfcpp::Rel<32, big_endian>& reloc,
7532 unsigned int r_type,
7535 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
7536 // section. We check here to avoid creating a dynamic reloc against
7537 // _GLOBAL_OFFSET_TABLE_.
7538 if (!target->has_got_section()
7539 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7540 target->got_section(symtab, layout);
7542 r_type = get_real_reloc_type(r_type);
7545 case elfcpp::R_ARM_NONE:
7546 case elfcpp::R_ARM_V4BX:
7547 case elfcpp::R_ARM_GNU_VTENTRY:
7548 case elfcpp::R_ARM_GNU_VTINHERIT:
7551 case elfcpp::R_ARM_ABS32:
7552 case elfcpp::R_ARM_ABS16:
7553 case elfcpp::R_ARM_ABS12:
7554 case elfcpp::R_ARM_THM_ABS5:
7555 case elfcpp::R_ARM_ABS8:
7556 case elfcpp::R_ARM_BASE_ABS:
7557 case elfcpp::R_ARM_MOVW_ABS_NC:
7558 case elfcpp::R_ARM_MOVT_ABS:
7559 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7560 case elfcpp::R_ARM_THM_MOVT_ABS:
7561 case elfcpp::R_ARM_ABS32_NOI:
7562 // Absolute addressing relocations.
7564 // Make a PLT entry if necessary.
7565 if (this->symbol_needs_plt_entry(gsym))
7567 target->make_plt_entry(symtab, layout, gsym);
7568 // Since this is not a PC-relative relocation, we may be
7569 // taking the address of a function. In that case we need to
7570 // set the entry in the dynamic symbol table to the address of
7572 if (gsym->is_from_dynobj() && !parameters->options().shared())
7573 gsym->set_needs_dynsym_value();
7575 // Make a dynamic relocation if necessary.
7576 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
7578 if (gsym->may_need_copy_reloc())
7580 target->copy_reloc(symtab, layout, object,
7581 data_shndx, output_section, gsym, reloc);
7583 else if ((r_type == elfcpp::R_ARM_ABS32
7584 || r_type == elfcpp::R_ARM_ABS32_NOI)
7585 && gsym->can_use_relative_reloc(false))
7587 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7588 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
7589 output_section, object,
7590 data_shndx, reloc.get_r_offset());
7594 check_non_pic(object, r_type);
7595 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7596 rel_dyn->add_global(gsym, r_type, output_section, object,
7597 data_shndx, reloc.get_r_offset());
7603 case elfcpp::R_ARM_GOTOFF32:
7604 case elfcpp::R_ARM_GOTOFF12:
7605 // We need a GOT section.
7606 target->got_section(symtab, layout);
7609 case elfcpp::R_ARM_REL32:
7610 case elfcpp::R_ARM_LDR_PC_G0:
7611 case elfcpp::R_ARM_SBREL32:
7612 case elfcpp::R_ARM_THM_PC8:
7613 case elfcpp::R_ARM_BASE_PREL:
7614 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7615 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7616 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7617 case elfcpp::R_ARM_MOVW_PREL_NC:
7618 case elfcpp::R_ARM_MOVT_PREL:
7619 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7620 case elfcpp::R_ARM_THM_MOVT_PREL:
7621 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7622 case elfcpp::R_ARM_THM_PC12:
7623 case elfcpp::R_ARM_REL32_NOI:
7624 case elfcpp::R_ARM_ALU_PC_G0_NC:
7625 case elfcpp::R_ARM_ALU_PC_G0:
7626 case elfcpp::R_ARM_ALU_PC_G1_NC:
7627 case elfcpp::R_ARM_ALU_PC_G1:
7628 case elfcpp::R_ARM_ALU_PC_G2:
7629 case elfcpp::R_ARM_LDR_PC_G1:
7630 case elfcpp::R_ARM_LDR_PC_G2:
7631 case elfcpp::R_ARM_LDRS_PC_G0:
7632 case elfcpp::R_ARM_LDRS_PC_G1:
7633 case elfcpp::R_ARM_LDRS_PC_G2:
7634 case elfcpp::R_ARM_LDC_PC_G0:
7635 case elfcpp::R_ARM_LDC_PC_G1:
7636 case elfcpp::R_ARM_LDC_PC_G2:
7637 case elfcpp::R_ARM_ALU_SB_G0_NC:
7638 case elfcpp::R_ARM_ALU_SB_G0:
7639 case elfcpp::R_ARM_ALU_SB_G1_NC:
7640 case elfcpp::R_ARM_ALU_SB_G1:
7641 case elfcpp::R_ARM_ALU_SB_G2:
7642 case elfcpp::R_ARM_LDR_SB_G0:
7643 case elfcpp::R_ARM_LDR_SB_G1:
7644 case elfcpp::R_ARM_LDR_SB_G2:
7645 case elfcpp::R_ARM_LDRS_SB_G0:
7646 case elfcpp::R_ARM_LDRS_SB_G1:
7647 case elfcpp::R_ARM_LDRS_SB_G2:
7648 case elfcpp::R_ARM_LDC_SB_G0:
7649 case elfcpp::R_ARM_LDC_SB_G1:
7650 case elfcpp::R_ARM_LDC_SB_G2:
7651 case elfcpp::R_ARM_MOVW_BREL_NC:
7652 case elfcpp::R_ARM_MOVT_BREL:
7653 case elfcpp::R_ARM_MOVW_BREL:
7654 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7655 case elfcpp::R_ARM_THM_MOVT_BREL:
7656 case elfcpp::R_ARM_THM_MOVW_BREL:
7657 // Relative addressing relocations.
7659 // Make a dynamic relocation if necessary.
7660 int flags = Symbol::NON_PIC_REF;
7661 if (gsym->needs_dynamic_reloc(flags))
7663 if (target->may_need_copy_reloc(gsym))
7665 target->copy_reloc(symtab, layout, object,
7666 data_shndx, output_section, gsym, reloc);
7670 check_non_pic(object, r_type);
7671 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7672 rel_dyn->add_global(gsym, r_type, output_section, object,
7673 data_shndx, reloc.get_r_offset());
7679 case elfcpp::R_ARM_PC24:
7680 case elfcpp::R_ARM_THM_CALL:
7681 case elfcpp::R_ARM_PLT32:
7682 case elfcpp::R_ARM_CALL:
7683 case elfcpp::R_ARM_JUMP24:
7684 case elfcpp::R_ARM_THM_JUMP24:
7685 case elfcpp::R_ARM_SBREL31:
7686 case elfcpp::R_ARM_PREL31:
7687 case elfcpp::R_ARM_THM_JUMP19:
7688 case elfcpp::R_ARM_THM_JUMP6:
7689 case elfcpp::R_ARM_THM_JUMP11:
7690 case elfcpp::R_ARM_THM_JUMP8:
7691 // All the relocation above are branches except for the PREL31 ones.
7692 // A PREL31 relocation can point to a personality function in a shared
7693 // library. In that case we want to use a PLT because we want to
7694 // call the personality routine and the dyanmic linkers we care about
7695 // do not support dynamic PREL31 relocations. An REL31 relocation may
7696 // point to a function whose unwinding behaviour is being described but
7697 // we will not mistakenly generate a PLT for that because we should use
7698 // a local section symbol.
7700 // If the symbol is fully resolved, this is just a relative
7701 // local reloc. Otherwise we need a PLT entry.
7702 if (gsym->final_value_is_known())
7704 // If building a shared library, we can also skip the PLT entry
7705 // if the symbol is defined in the output file and is protected
7707 if (gsym->is_defined()
7708 && !gsym->is_from_dynobj()
7709 && !gsym->is_preemptible())
7711 target->make_plt_entry(symtab, layout, gsym);
7714 case elfcpp::R_ARM_GOT_BREL:
7715 case elfcpp::R_ARM_GOT_ABS:
7716 case elfcpp::R_ARM_GOT_PREL:
7718 // The symbol requires a GOT entry.
7719 Arm_output_data_got<big_endian>* got =
7720 target->got_section(symtab, layout);
7721 if (gsym->final_value_is_known())
7722 got->add_global(gsym, GOT_TYPE_STANDARD);
7725 // If this symbol is not fully resolved, we need to add a
7726 // GOT entry with a dynamic relocation.
7727 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7728 if (gsym->is_from_dynobj()
7729 || gsym->is_undefined()
7730 || gsym->is_preemptible())
7731 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
7732 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
7735 if (got->add_global(gsym, GOT_TYPE_STANDARD))
7736 rel_dyn->add_global_relative(
7737 gsym, elfcpp::R_ARM_RELATIVE, got,
7738 gsym->got_offset(GOT_TYPE_STANDARD));
7744 case elfcpp::R_ARM_TARGET1:
7745 case elfcpp::R_ARM_TARGET2:
7746 // These should have been mapped to other types already.
7748 case elfcpp::R_ARM_COPY:
7749 case elfcpp::R_ARM_GLOB_DAT:
7750 case elfcpp::R_ARM_JUMP_SLOT:
7751 case elfcpp::R_ARM_RELATIVE:
7752 // These are relocations which should only be seen by the
7753 // dynamic linker, and should never be seen here.
7754 gold_error(_("%s: unexpected reloc %u in object file"),
7755 object->name().c_str(), r_type);
7758 // These are initial tls relocs, which are expected when
7760 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7761 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7762 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7763 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7764 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7766 const bool is_final = gsym->final_value_is_known();
7767 const tls::Tls_optimization optimized_type
7768 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
7771 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7772 if (optimized_type == tls::TLSOPT_NONE)
7774 // Create a pair of GOT entries for the module index and
7775 // dtv-relative offset.
7776 Arm_output_data_got<big_endian>* got
7777 = target->got_section(symtab, layout);
7778 if (!parameters->doing_static_link())
7779 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
7780 target->rel_dyn_section(layout),
7781 elfcpp::R_ARM_TLS_DTPMOD32,
7782 elfcpp::R_ARM_TLS_DTPOFF32);
7784 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
7787 // FIXME: TLS optimization not supported yet.
7791 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7792 if (optimized_type == tls::TLSOPT_NONE)
7794 // Create a GOT entry for the module index.
7795 target->got_mod_index_entry(symtab, layout, object);
7798 // FIXME: TLS optimization not supported yet.
7802 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7805 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7806 layout->set_has_static_tls();
7807 if (optimized_type == tls::TLSOPT_NONE)
7809 // Create a GOT entry for the tp-relative offset.
7810 Arm_output_data_got<big_endian>* got
7811 = target->got_section(symtab, layout);
7812 if (!parameters->doing_static_link())
7813 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
7814 target->rel_dyn_section(layout),
7815 elfcpp::R_ARM_TLS_TPOFF32);
7816 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
7818 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
7819 unsigned int got_offset =
7820 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
7821 got->add_static_reloc(got_offset,
7822 elfcpp::R_ARM_TLS_TPOFF32, gsym);
7826 // FIXME: TLS optimization not supported yet.
7830 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7831 layout->set_has_static_tls();
7832 if (parameters->options().shared())
7834 // We need to create a dynamic relocation.
7835 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7836 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
7837 output_section, object,
7838 data_shndx, reloc.get_r_offset());
7849 unsupported_reloc_global(object, r_type, gsym);
7854 // Process relocations for gc.
7856 template<bool big_endian>
7858 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
7860 Sized_relobj<32, big_endian>* object,
7861 unsigned int data_shndx,
7863 const unsigned char* prelocs,
7865 Output_section* output_section,
7866 bool needs_special_offset_handling,
7867 size_t local_symbol_count,
7868 const unsigned char* plocal_symbols)
7870 typedef Target_arm<big_endian> Arm;
7871 typedef typename Target_arm<big_endian>::Scan Scan;
7873 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
7882 needs_special_offset_handling,
7887 // Scan relocations for a section.
7889 template<bool big_endian>
7891 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
7893 Sized_relobj<32, big_endian>* object,
7894 unsigned int data_shndx,
7895 unsigned int sh_type,
7896 const unsigned char* prelocs,
7898 Output_section* output_section,
7899 bool needs_special_offset_handling,
7900 size_t local_symbol_count,
7901 const unsigned char* plocal_symbols)
7903 typedef typename Target_arm<big_endian>::Scan Scan;
7904 if (sh_type == elfcpp::SHT_RELA)
7906 gold_error(_("%s: unsupported RELA reloc section"),
7907 object->name().c_str());
7911 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
7920 needs_special_offset_handling,
7925 // Finalize the sections.
7927 template<bool big_endian>
7929 Target_arm<big_endian>::do_finalize_sections(
7931 const Input_objects* input_objects,
7932 Symbol_table* symtab)
7934 // Create an empty uninitialized attribute section if we still don't have it
7936 if (this->attributes_section_data_ == NULL)
7937 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
7939 // Merge processor-specific flags.
7940 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
7941 p != input_objects->relobj_end();
7944 // If this input file is a binary file, it has no processor
7945 // specific flags and attributes section.
7946 Input_file::Format format = (*p)->input_file()->format();
7947 if (format != Input_file::FORMAT_ELF)
7949 gold_assert(format == Input_file::FORMAT_BINARY);
7953 Arm_relobj<big_endian>* arm_relobj =
7954 Arm_relobj<big_endian>::as_arm_relobj(*p);
7955 this->merge_processor_specific_flags(
7957 arm_relobj->processor_specific_flags());
7958 this->merge_object_attributes(arm_relobj->name().c_str(),
7959 arm_relobj->attributes_section_data());
7963 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
7964 p != input_objects->dynobj_end();
7967 Arm_dynobj<big_endian>* arm_dynobj =
7968 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
7969 this->merge_processor_specific_flags(
7971 arm_dynobj->processor_specific_flags());
7972 this->merge_object_attributes(arm_dynobj->name().c_str(),
7973 arm_dynobj->attributes_section_data());
7977 const Object_attribute* cpu_arch_attr =
7978 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
7979 if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
7980 this->set_may_use_blx(true);
7982 // Check if we need to use Cortex-A8 workaround.
7983 if (parameters->options().user_set_fix_cortex_a8())
7984 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
7987 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
7988 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
7990 const Object_attribute* cpu_arch_profile_attr =
7991 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
7992 this->fix_cortex_a8_ =
7993 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
7994 && (cpu_arch_profile_attr->int_value() == 'A'
7995 || cpu_arch_profile_attr->int_value() == 0));
7998 // Check if we can use V4BX interworking.
7999 // The V4BX interworking stub contains BX instruction,
8000 // which is not specified for some profiles.
8001 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
8002 && !this->may_use_blx())
8003 gold_error(_("unable to provide V4BX reloc interworking fix up; "
8004 "the target profile does not support BX instruction"));
8006 // Fill in some more dynamic tags.
8007 const Reloc_section* rel_plt = (this->plt_ == NULL
8009 : this->plt_->rel_plt());
8010 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
8011 this->rel_dyn_, true, false);
8013 // Emit any relocs we saved in an attempt to avoid generating COPY
8015 if (this->copy_relocs_.any_saved_relocs())
8016 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8018 // Handle the .ARM.exidx section.
8019 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8020 if (exidx_section != NULL
8021 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
8022 && !parameters->options().relocatable())
8024 // Create __exidx_start and __exdix_end symbols.
8025 symtab->define_in_output_data("__exidx_start", NULL,
8026 Symbol_table::PREDEFINED,
8027 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8028 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8030 symtab->define_in_output_data("__exidx_end", NULL,
8031 Symbol_table::PREDEFINED,
8032 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8033 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8036 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8037 // the .ARM.exidx section.
8038 if (!layout->script_options()->saw_phdrs_clause())
8040 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
8042 Output_segment* exidx_segment =
8043 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8044 exidx_segment->add_output_section(exidx_section, elfcpp::PF_R,
8049 // Create an .ARM.attributes section if there is not one already.
8050 Output_attributes_section_data* attributes_section =
8051 new Output_attributes_section_data(*this->attributes_section_data_);
8052 layout->add_output_section_data(".ARM.attributes",
8053 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8054 attributes_section, false, false, false,
8058 // Return whether a direct absolute static relocation needs to be applied.
8059 // In cases where Scan::local() or Scan::global() has created
8060 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8061 // of the relocation is carried in the data, and we must not
8062 // apply the static relocation.
8064 template<bool big_endian>
8066 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8067 const Sized_symbol<32>* gsym,
8070 Output_section* output_section)
8072 // If the output section is not allocated, then we didn't call
8073 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8075 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8078 // For local symbols, we will have created a non-RELATIVE dynamic
8079 // relocation only if (a) the output is position independent,
8080 // (b) the relocation is absolute (not pc- or segment-relative), and
8081 // (c) the relocation is not 32 bits wide.
8083 return !(parameters->options().output_is_position_independent()
8084 && (ref_flags & Symbol::ABSOLUTE_REF)
8087 // For global symbols, we use the same helper routines used in the
8088 // scan pass. If we did not create a dynamic relocation, or if we
8089 // created a RELATIVE dynamic relocation, we should apply the static
8091 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8092 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8093 && gsym->can_use_relative_reloc(ref_flags
8094 & Symbol::FUNCTION_CALL);
8095 return !has_dyn || is_rel;
8098 // Perform a relocation.
8100 template<bool big_endian>
8102 Target_arm<big_endian>::Relocate::relocate(
8103 const Relocate_info<32, big_endian>* relinfo,
8105 Output_section *output_section,
8107 const elfcpp::Rel<32, big_endian>& rel,
8108 unsigned int r_type,
8109 const Sized_symbol<32>* gsym,
8110 const Symbol_value<32>* psymval,
8111 unsigned char* view,
8112 Arm_address address,
8113 section_size_type view_size)
8115 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8117 r_type = get_real_reloc_type(r_type);
8118 const Arm_reloc_property* reloc_property =
8119 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8120 if (reloc_property == NULL)
8122 std::string reloc_name =
8123 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8124 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8125 _("cannot relocate %s in object file"),
8126 reloc_name.c_str());
8130 const Arm_relobj<big_endian>* object =
8131 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8133 // If the final branch target of a relocation is THUMB instruction, this
8134 // is 1. Otherwise it is 0.
8135 Arm_address thumb_bit = 0;
8136 Symbol_value<32> symval;
8137 bool is_weakly_undefined_without_plt = false;
8138 if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8142 // This is a global symbol. Determine if we use PLT and if the
8143 // final target is THUMB.
8144 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
8146 // This uses a PLT, change the symbol value.
8147 symval.set_output_value(target->plt_section()->address()
8148 + gsym->plt_offset());
8151 else if (gsym->is_weak_undefined())
8153 // This is a weakly undefined symbol and we do not use PLT
8154 // for this relocation. A branch targeting this symbol will
8155 // be converted into an NOP.
8156 is_weakly_undefined_without_plt = true;
8160 // Set thumb bit if symbol:
8161 // -Has type STT_ARM_TFUNC or
8162 // -Has type STT_FUNC, is defined and with LSB in value set.
8164 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8165 || (gsym->type() == elfcpp::STT_FUNC
8166 && !gsym->is_undefined()
8167 && ((psymval->value(object, 0) & 1) != 0)))
8174 // This is a local symbol. Determine if the final target is THUMB.
8175 // We saved this information when all the local symbols were read.
8176 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8177 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8178 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8183 // This is a fake relocation synthesized for a stub. It does not have
8184 // a real symbol. We just look at the LSB of the symbol value to
8185 // determine if the target is THUMB or not.
8186 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8189 // Strip LSB if this points to a THUMB target.
8191 && reloc_property->uses_thumb_bit()
8192 && ((psymval->value(object, 0) & 1) != 0))
8194 Arm_address stripped_value =
8195 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8196 symval.set_output_value(stripped_value);
8200 // Get the GOT offset if needed.
8201 // The GOT pointer points to the end of the GOT section.
8202 // We need to subtract the size of the GOT section to get
8203 // the actual offset to use in the relocation.
8204 bool have_got_offset = false;
8205 unsigned int got_offset = 0;
8208 case elfcpp::R_ARM_GOT_BREL:
8209 case elfcpp::R_ARM_GOT_PREL:
8212 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8213 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8214 - target->got_size());
8218 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8219 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
8220 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8221 - target->got_size());
8223 have_got_offset = true;
8230 // To look up relocation stubs, we need to pass the symbol table index of
8232 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8234 // Get the addressing origin of the output segment defining the
8235 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8236 Arm_address sym_origin = 0;
8237 if (reloc_property->uses_symbol_base())
8239 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8240 // R_ARM_BASE_ABS with the NULL symbol will give the
8241 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8242 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8243 sym_origin = target->got_plt_section()->address();
8244 else if (gsym == NULL)
8246 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8247 sym_origin = gsym->output_segment()->vaddr();
8248 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8249 sym_origin = gsym->output_data()->address();
8251 // TODO: Assumes the segment base to be zero for the global symbols
8252 // till the proper support for the segment-base-relative addressing
8253 // will be implemented. This is consistent with GNU ld.
8256 // For relative addressing relocation, find out the relative address base.
8257 Arm_address relative_address_base = 0;
8258 switch(reloc_property->relative_address_base())
8260 case Arm_reloc_property::RAB_NONE:
8261 // Relocations with relative address bases RAB_TLS and RAB_tp are
8262 // handled by relocate_tls. So we do not need to do anything here.
8263 case Arm_reloc_property::RAB_TLS:
8264 case Arm_reloc_property::RAB_tp:
8266 case Arm_reloc_property::RAB_B_S:
8267 relative_address_base = sym_origin;
8269 case Arm_reloc_property::RAB_GOT_ORG:
8270 relative_address_base = target->got_plt_section()->address();
8272 case Arm_reloc_property::RAB_P:
8273 relative_address_base = address;
8275 case Arm_reloc_property::RAB_Pa:
8276 relative_address_base = address & 0xfffffffcU;
8282 typename Arm_relocate_functions::Status reloc_status =
8283 Arm_relocate_functions::STATUS_OKAY;
8284 bool check_overflow = reloc_property->checks_overflow();
8287 case elfcpp::R_ARM_NONE:
8290 case elfcpp::R_ARM_ABS8:
8291 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8293 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
8296 case elfcpp::R_ARM_ABS12:
8297 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8299 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
8302 case elfcpp::R_ARM_ABS16:
8303 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8305 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
8308 case elfcpp::R_ARM_ABS32:
8309 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8311 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8315 case elfcpp::R_ARM_ABS32_NOI:
8316 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8318 // No thumb bit for this relocation: (S + A)
8319 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8323 case elfcpp::R_ARM_MOVW_ABS_NC:
8324 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8326 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
8331 case elfcpp::R_ARM_MOVT_ABS:
8332 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8334 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
8337 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8338 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8340 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
8341 0, thumb_bit, false);
8344 case elfcpp::R_ARM_THM_MOVT_ABS:
8345 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8347 reloc_status = Arm_relocate_functions::thm_movt(view, object,
8351 case elfcpp::R_ARM_MOVW_PREL_NC:
8352 case elfcpp::R_ARM_MOVW_BREL_NC:
8353 case elfcpp::R_ARM_MOVW_BREL:
8355 Arm_relocate_functions::movw(view, object, psymval,
8356 relative_address_base, thumb_bit,
8360 case elfcpp::R_ARM_MOVT_PREL:
8361 case elfcpp::R_ARM_MOVT_BREL:
8363 Arm_relocate_functions::movt(view, object, psymval,
8364 relative_address_base);
8367 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8368 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8369 case elfcpp::R_ARM_THM_MOVW_BREL:
8371 Arm_relocate_functions::thm_movw(view, object, psymval,
8372 relative_address_base,
8373 thumb_bit, check_overflow);
8376 case elfcpp::R_ARM_THM_MOVT_PREL:
8377 case elfcpp::R_ARM_THM_MOVT_BREL:
8379 Arm_relocate_functions::thm_movt(view, object, psymval,
8380 relative_address_base);
8383 case elfcpp::R_ARM_REL32:
8384 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8385 address, thumb_bit);
8388 case elfcpp::R_ARM_THM_ABS5:
8389 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8391 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
8394 // Thumb long branches.
8395 case elfcpp::R_ARM_THM_CALL:
8396 case elfcpp::R_ARM_THM_XPC22:
8397 case elfcpp::R_ARM_THM_JUMP24:
8399 Arm_relocate_functions::thumb_branch_common(
8400 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8401 thumb_bit, is_weakly_undefined_without_plt);
8404 case elfcpp::R_ARM_GOTOFF32:
8406 Arm_address got_origin;
8407 got_origin = target->got_plt_section()->address();
8408 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8409 got_origin, thumb_bit);
8413 case elfcpp::R_ARM_BASE_PREL:
8414 gold_assert(gsym != NULL);
8416 Arm_relocate_functions::base_prel(view, sym_origin, address);
8419 case elfcpp::R_ARM_BASE_ABS:
8421 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8425 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
8429 case elfcpp::R_ARM_GOT_BREL:
8430 gold_assert(have_got_offset);
8431 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
8434 case elfcpp::R_ARM_GOT_PREL:
8435 gold_assert(have_got_offset);
8436 // Get the address origin for GOT PLT, which is allocated right
8437 // after the GOT section, to calculate an absolute address of
8438 // the symbol GOT entry (got_origin + got_offset).
8439 Arm_address got_origin;
8440 got_origin = target->got_plt_section()->address();
8441 reloc_status = Arm_relocate_functions::got_prel(view,
8442 got_origin + got_offset,
8446 case elfcpp::R_ARM_PLT32:
8447 case elfcpp::R_ARM_CALL:
8448 case elfcpp::R_ARM_JUMP24:
8449 case elfcpp::R_ARM_XPC25:
8450 gold_assert(gsym == NULL
8451 || gsym->has_plt_offset()
8452 || gsym->final_value_is_known()
8453 || (gsym->is_defined()
8454 && !gsym->is_from_dynobj()
8455 && !gsym->is_preemptible()));
8457 Arm_relocate_functions::arm_branch_common(
8458 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8459 thumb_bit, is_weakly_undefined_without_plt);
8462 case elfcpp::R_ARM_THM_JUMP19:
8464 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
8468 case elfcpp::R_ARM_THM_JUMP6:
8470 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
8473 case elfcpp::R_ARM_THM_JUMP8:
8475 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
8478 case elfcpp::R_ARM_THM_JUMP11:
8480 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
8483 case elfcpp::R_ARM_PREL31:
8484 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
8485 address, thumb_bit);
8488 case elfcpp::R_ARM_V4BX:
8489 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
8491 const bool is_v4bx_interworking =
8492 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
8494 Arm_relocate_functions::v4bx(relinfo, view, object, address,
8495 is_v4bx_interworking);
8499 case elfcpp::R_ARM_THM_PC8:
8501 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
8504 case elfcpp::R_ARM_THM_PC12:
8506 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
8509 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8511 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
8515 case elfcpp::R_ARM_ALU_PC_G0_NC:
8516 case elfcpp::R_ARM_ALU_PC_G0:
8517 case elfcpp::R_ARM_ALU_PC_G1_NC:
8518 case elfcpp::R_ARM_ALU_PC_G1:
8519 case elfcpp::R_ARM_ALU_PC_G2:
8520 case elfcpp::R_ARM_ALU_SB_G0_NC:
8521 case elfcpp::R_ARM_ALU_SB_G0:
8522 case elfcpp::R_ARM_ALU_SB_G1_NC:
8523 case elfcpp::R_ARM_ALU_SB_G1:
8524 case elfcpp::R_ARM_ALU_SB_G2:
8526 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
8527 reloc_property->group_index(),
8528 relative_address_base,
8529 thumb_bit, check_overflow);
8532 case elfcpp::R_ARM_LDR_PC_G0:
8533 case elfcpp::R_ARM_LDR_PC_G1:
8534 case elfcpp::R_ARM_LDR_PC_G2:
8535 case elfcpp::R_ARM_LDR_SB_G0:
8536 case elfcpp::R_ARM_LDR_SB_G1:
8537 case elfcpp::R_ARM_LDR_SB_G2:
8539 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
8540 reloc_property->group_index(),
8541 relative_address_base);
8544 case elfcpp::R_ARM_LDRS_PC_G0:
8545 case elfcpp::R_ARM_LDRS_PC_G1:
8546 case elfcpp::R_ARM_LDRS_PC_G2:
8547 case elfcpp::R_ARM_LDRS_SB_G0:
8548 case elfcpp::R_ARM_LDRS_SB_G1:
8549 case elfcpp::R_ARM_LDRS_SB_G2:
8551 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
8552 reloc_property->group_index(),
8553 relative_address_base);
8556 case elfcpp::R_ARM_LDC_PC_G0:
8557 case elfcpp::R_ARM_LDC_PC_G1:
8558 case elfcpp::R_ARM_LDC_PC_G2:
8559 case elfcpp::R_ARM_LDC_SB_G0:
8560 case elfcpp::R_ARM_LDC_SB_G1:
8561 case elfcpp::R_ARM_LDC_SB_G2:
8563 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
8564 reloc_property->group_index(),
8565 relative_address_base);
8568 // These are initial tls relocs, which are expected when
8570 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8571 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8572 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8573 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8574 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8576 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
8577 view, address, view_size);
8584 // Report any errors.
8585 switch (reloc_status)
8587 case Arm_relocate_functions::STATUS_OKAY:
8589 case Arm_relocate_functions::STATUS_OVERFLOW:
8590 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8591 _("relocation overflow in %s"),
8592 reloc_property->name().c_str());
8594 case Arm_relocate_functions::STATUS_BAD_RELOC:
8595 gold_error_at_location(
8599 _("unexpected opcode while processing relocation %s"),
8600 reloc_property->name().c_str());
8609 // Perform a TLS relocation.
8611 template<bool big_endian>
8612 inline typename Arm_relocate_functions<big_endian>::Status
8613 Target_arm<big_endian>::Relocate::relocate_tls(
8614 const Relocate_info<32, big_endian>* relinfo,
8615 Target_arm<big_endian>* target,
8617 const elfcpp::Rel<32, big_endian>& rel,
8618 unsigned int r_type,
8619 const Sized_symbol<32>* gsym,
8620 const Symbol_value<32>* psymval,
8621 unsigned char* view,
8622 elfcpp::Elf_types<32>::Elf_Addr address,
8623 section_size_type /*view_size*/ )
8625 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
8626 typedef Relocate_functions<32, big_endian> RelocFuncs;
8627 Output_segment* tls_segment = relinfo->layout->tls_segment();
8629 const Sized_relobj<32, big_endian>* object = relinfo->object;
8631 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
8633 const bool is_final = (gsym == NULL
8634 ? !parameters->options().shared()
8635 : gsym->final_value_is_known());
8636 const tls::Tls_optimization optimized_type
8637 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8640 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8642 unsigned int got_type = GOT_TYPE_TLS_PAIR;
8643 unsigned int got_offset;
8646 gold_assert(gsym->has_got_offset(got_type));
8647 got_offset = gsym->got_offset(got_type) - target->got_size();
8651 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8652 gold_assert(object->local_has_got_offset(r_sym, got_type));
8653 got_offset = (object->local_got_offset(r_sym, got_type)
8654 - target->got_size());
8656 if (optimized_type == tls::TLSOPT_NONE)
8658 Arm_address got_entry =
8659 target->got_plt_section()->address() + got_offset;
8661 // Relocate the field with the PC relative offset of the pair of
8663 RelocFuncs::pcrel32(view, got_entry, address);
8664 return ArmRelocFuncs::STATUS_OKAY;
8669 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8670 if (optimized_type == tls::TLSOPT_NONE)
8672 // Relocate the field with the offset of the GOT entry for
8673 // the module index.
8674 unsigned int got_offset;
8675 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
8676 - target->got_size());
8677 Arm_address got_entry =
8678 target->got_plt_section()->address() + got_offset;
8680 // Relocate the field with the PC relative offset of the pair of
8682 RelocFuncs::pcrel32(view, got_entry, address);
8683 return ArmRelocFuncs::STATUS_OKAY;
8687 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8688 RelocFuncs::rel32(view, value);
8689 return ArmRelocFuncs::STATUS_OKAY;
8691 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8692 if (optimized_type == tls::TLSOPT_NONE)
8694 // Relocate the field with the offset of the GOT entry for
8695 // the tp-relative offset of the symbol.
8696 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
8697 unsigned int got_offset;
8700 gold_assert(gsym->has_got_offset(got_type));
8701 got_offset = gsym->got_offset(got_type);
8705 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8706 gold_assert(object->local_has_got_offset(r_sym, got_type));
8707 got_offset = object->local_got_offset(r_sym, got_type);
8710 // All GOT offsets are relative to the end of the GOT.
8711 got_offset -= target->got_size();
8713 Arm_address got_entry =
8714 target->got_plt_section()->address() + got_offset;
8716 // Relocate the field with the PC relative offset of the GOT entry.
8717 RelocFuncs::pcrel32(view, got_entry, address);
8718 return ArmRelocFuncs::STATUS_OKAY;
8722 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8723 // If we're creating a shared library, a dynamic relocation will
8724 // have been created for this location, so do not apply it now.
8725 if (!parameters->options().shared())
8727 gold_assert(tls_segment != NULL);
8729 // $tp points to the TCB, which is followed by the TLS, so we
8730 // need to add TCB size to the offset.
8731 Arm_address aligned_tcb_size =
8732 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
8733 RelocFuncs::rel32(view, value + aligned_tcb_size);
8736 return ArmRelocFuncs::STATUS_OKAY;
8742 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8743 _("unsupported reloc %u"),
8745 return ArmRelocFuncs::STATUS_BAD_RELOC;
8748 // Relocate section data.
8750 template<bool big_endian>
8752 Target_arm<big_endian>::relocate_section(
8753 const Relocate_info<32, big_endian>* relinfo,
8754 unsigned int sh_type,
8755 const unsigned char* prelocs,
8757 Output_section* output_section,
8758 bool needs_special_offset_handling,
8759 unsigned char* view,
8760 Arm_address address,
8761 section_size_type view_size,
8762 const Reloc_symbol_changes* reloc_symbol_changes)
8764 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
8765 gold_assert(sh_type == elfcpp::SHT_REL);
8767 // See if we are relocating a relaxed input section. If so, the view
8768 // covers the whole output section and we need to adjust accordingly.
8769 if (needs_special_offset_handling)
8771 const Output_relaxed_input_section* poris =
8772 output_section->find_relaxed_input_section(relinfo->object,
8773 relinfo->data_shndx);
8776 Arm_address section_address = poris->address();
8777 section_size_type section_size = poris->data_size();
8779 gold_assert((section_address >= address)
8780 && ((section_address + section_size)
8781 <= (address + view_size)));
8783 off_t offset = section_address - address;
8786 view_size = section_size;
8790 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
8797 needs_special_offset_handling,
8801 reloc_symbol_changes);
8804 // Return the size of a relocation while scanning during a relocatable
8807 template<bool big_endian>
8809 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
8810 unsigned int r_type,
8813 r_type = get_real_reloc_type(r_type);
8814 const Arm_reloc_property* arp =
8815 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8820 std::string reloc_name =
8821 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8822 gold_error(_("%s: unexpected %s in object file"),
8823 object->name().c_str(), reloc_name.c_str());
8828 // Scan the relocs during a relocatable link.
8830 template<bool big_endian>
8832 Target_arm<big_endian>::scan_relocatable_relocs(
8833 Symbol_table* symtab,
8835 Sized_relobj<32, big_endian>* object,
8836 unsigned int data_shndx,
8837 unsigned int sh_type,
8838 const unsigned char* prelocs,
8840 Output_section* output_section,
8841 bool needs_special_offset_handling,
8842 size_t local_symbol_count,
8843 const unsigned char* plocal_symbols,
8844 Relocatable_relocs* rr)
8846 gold_assert(sh_type == elfcpp::SHT_REL);
8848 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
8849 Relocatable_size_for_reloc> Scan_relocatable_relocs;
8851 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
8852 Scan_relocatable_relocs>(
8860 needs_special_offset_handling,
8866 // Relocate a section during a relocatable link.
8868 template<bool big_endian>
8870 Target_arm<big_endian>::relocate_for_relocatable(
8871 const Relocate_info<32, big_endian>* relinfo,
8872 unsigned int sh_type,
8873 const unsigned char* prelocs,
8875 Output_section* output_section,
8876 off_t offset_in_output_section,
8877 const Relocatable_relocs* rr,
8878 unsigned char* view,
8879 Arm_address view_address,
8880 section_size_type view_size,
8881 unsigned char* reloc_view,
8882 section_size_type reloc_view_size)
8884 gold_assert(sh_type == elfcpp::SHT_REL);
8886 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
8891 offset_in_output_section,
8900 // Return the value to use for a dynamic symbol which requires special
8901 // treatment. This is how we support equality comparisons of function
8902 // pointers across shared library boundaries, as described in the
8903 // processor specific ABI supplement.
8905 template<bool big_endian>
8907 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
8909 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
8910 return this->plt_section()->address() + gsym->plt_offset();
8913 // Map platform-specific relocs to real relocs
8915 template<bool big_endian>
8917 Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
8921 case elfcpp::R_ARM_TARGET1:
8922 // This is either R_ARM_ABS32 or R_ARM_REL32;
8923 return elfcpp::R_ARM_ABS32;
8925 case elfcpp::R_ARM_TARGET2:
8926 // This can be any reloc type but ususally is R_ARM_GOT_PREL
8927 return elfcpp::R_ARM_GOT_PREL;
8934 // Whether if two EABI versions V1 and V2 are compatible.
8936 template<bool big_endian>
8938 Target_arm<big_endian>::are_eabi_versions_compatible(
8939 elfcpp::Elf_Word v1,
8940 elfcpp::Elf_Word v2)
8942 // v4 and v5 are the same spec before and after it was released,
8943 // so allow mixing them.
8944 if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
8945 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
8951 // Combine FLAGS from an input object called NAME and the processor-specific
8952 // flags in the ELF header of the output. Much of this is adapted from the
8953 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
8954 // in bfd/elf32-arm.c.
8956 template<bool big_endian>
8958 Target_arm<big_endian>::merge_processor_specific_flags(
8959 const std::string& name,
8960 elfcpp::Elf_Word flags)
8962 if (this->are_processor_specific_flags_set())
8964 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
8966 // Nothing to merge if flags equal to those in output.
8967 if (flags == out_flags)
8970 // Complain about various flag mismatches.
8971 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
8972 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
8973 if (!this->are_eabi_versions_compatible(version1, version2))
8974 gold_error(_("Source object %s has EABI version %d but output has "
8975 "EABI version %d."),
8977 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
8978 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
8982 // If the input is the default architecture and had the default
8983 // flags then do not bother setting the flags for the output
8984 // architecture, instead allow future merges to do this. If no
8985 // future merges ever set these flags then they will retain their
8986 // uninitialised values, which surprise surprise, correspond
8987 // to the default values.
8991 // This is the first time, just copy the flags.
8992 // We only copy the EABI version for now.
8993 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
8997 // Adjust ELF file header.
8998 template<bool big_endian>
9000 Target_arm<big_endian>::do_adjust_elf_header(
9001 unsigned char* view,
9004 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
9006 elfcpp::Ehdr<32, big_endian> ehdr(view);
9007 unsigned char e_ident[elfcpp::EI_NIDENT];
9008 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
9010 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
9011 == elfcpp::EF_ARM_EABI_UNKNOWN)
9012 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
9014 e_ident[elfcpp::EI_OSABI] = 0;
9015 e_ident[elfcpp::EI_ABIVERSION] = 0;
9017 // FIXME: Do EF_ARM_BE8 adjustment.
9019 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
9020 oehdr.put_e_ident(e_ident);
9023 // do_make_elf_object to override the same function in the base class.
9024 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
9025 // to store ARM specific information. Hence we need to have our own
9026 // ELF object creation.
9028 template<bool big_endian>
9030 Target_arm<big_endian>::do_make_elf_object(
9031 const std::string& name,
9032 Input_file* input_file,
9033 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
9035 int et = ehdr.get_e_type();
9036 if (et == elfcpp::ET_REL)
9038 Arm_relobj<big_endian>* obj =
9039 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
9043 else if (et == elfcpp::ET_DYN)
9045 Sized_dynobj<32, big_endian>* obj =
9046 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
9052 gold_error(_("%s: unsupported ELF file type %d"),
9058 // Read the architecture from the Tag_also_compatible_with attribute, if any.
9059 // Returns -1 if no architecture could be read.
9060 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
9062 template<bool big_endian>
9064 Target_arm<big_endian>::get_secondary_compatible_arch(
9065 const Attributes_section_data* pasd)
9067 const Object_attribute *known_attributes =
9068 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9070 // Note: the tag and its argument below are uleb128 values, though
9071 // currently-defined values fit in one byte for each.
9072 const std::string& sv =
9073 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
9075 && sv.data()[0] == elfcpp::Tag_CPU_arch
9076 && (sv.data()[1] & 128) != 128)
9077 return sv.data()[1];
9079 // This tag is "safely ignorable", so don't complain if it looks funny.
9083 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
9084 // The tag is removed if ARCH is -1.
9085 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
9087 template<bool big_endian>
9089 Target_arm<big_endian>::set_secondary_compatible_arch(
9090 Attributes_section_data* pasd,
9093 Object_attribute *known_attributes =
9094 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9098 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
9102 // Note: the tag and its argument below are uleb128 values, though
9103 // currently-defined values fit in one byte for each.
9105 sv[0] = elfcpp::Tag_CPU_arch;
9106 gold_assert(arch != 0);
9110 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
9113 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
9115 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
9117 template<bool big_endian>
9119 Target_arm<big_endian>::tag_cpu_arch_combine(
9122 int* secondary_compat_out,
9124 int secondary_compat)
9126 #define T(X) elfcpp::TAG_CPU_ARCH_##X
9127 static const int v6t2[] =
9139 static const int v6k[] =
9152 static const int v7[] =
9166 static const int v6_m[] =
9181 static const int v6s_m[] =
9197 static const int v7e_m[] =
9214 static const int v4t_plus_v6_m[] =
9230 T(V4T_PLUS_V6_M) // V4T plus V6_M.
9232 static const int *comb[] =
9240 // Pseudo-architecture.
9244 // Check we've not got a higher architecture than we know about.
9246 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
9248 gold_error(_("%s: unknown CPU architecture"), name);
9252 // Override old tag if we have a Tag_also_compatible_with on the output.
9254 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
9255 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
9256 oldtag = T(V4T_PLUS_V6_M);
9258 // And override the new tag if we have a Tag_also_compatible_with on the
9261 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
9262 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
9263 newtag = T(V4T_PLUS_V6_M);
9265 // Architectures before V6KZ add features monotonically.
9266 int tagh = std::max(oldtag, newtag);
9267 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
9270 int tagl = std::min(oldtag, newtag);
9271 int result = comb[tagh - T(V6T2)][tagl];
9273 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
9274 // as the canonical version.
9275 if (result == T(V4T_PLUS_V6_M))
9278 *secondary_compat_out = T(V6_M);
9281 *secondary_compat_out = -1;
9285 gold_error(_("%s: conflicting CPU architectures %d/%d"),
9286 name, oldtag, newtag);
9294 // Helper to print AEABI enum tag value.
9296 template<bool big_endian>
9298 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
9300 static const char *aeabi_enum_names[] =
9301 { "", "variable-size", "32-bit", "" };
9302 const size_t aeabi_enum_names_size =
9303 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
9305 if (value < aeabi_enum_names_size)
9306 return std::string(aeabi_enum_names[value]);
9310 sprintf(buffer, "<unknown value %u>", value);
9311 return std::string(buffer);
9315 // Return the string value to store in TAG_CPU_name.
9317 template<bool big_endian>
9319 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
9321 static const char *name_table[] = {
9322 // These aren't real CPU names, but we can't guess
9323 // that from the architecture version alone.
9339 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
9341 if (value < name_table_size)
9342 return std::string(name_table[value]);
9346 sprintf(buffer, "<unknown CPU value %u>", value);
9347 return std::string(buffer);
9351 // Merge object attributes from input file called NAME with those of the
9352 // output. The input object attributes are in the object pointed by PASD.
9354 template<bool big_endian>
9356 Target_arm<big_endian>::merge_object_attributes(
9358 const Attributes_section_data* pasd)
9360 // Return if there is no attributes section data.
9364 // If output has no object attributes, just copy.
9365 if (this->attributes_section_data_ == NULL)
9367 this->attributes_section_data_ = new Attributes_section_data(*pasd);
9371 const int vendor = Object_attribute::OBJ_ATTR_PROC;
9372 const Object_attribute* in_attr = pasd->known_attributes(vendor);
9373 Object_attribute* out_attr =
9374 this->attributes_section_data_->known_attributes(vendor);
9376 // This needs to happen before Tag_ABI_FP_number_model is merged. */
9377 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
9378 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
9380 // Ignore mismatches if the object doesn't use floating point. */
9381 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
9382 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
9383 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
9384 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0)
9385 gold_error(_("%s uses VFP register arguments, output does not"),
9389 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
9391 // Merge this attribute with existing attributes.
9394 case elfcpp::Tag_CPU_raw_name:
9395 case elfcpp::Tag_CPU_name:
9396 // These are merged after Tag_CPU_arch.
9399 case elfcpp::Tag_ABI_optimization_goals:
9400 case elfcpp::Tag_ABI_FP_optimization_goals:
9401 // Use the first value seen.
9404 case elfcpp::Tag_CPU_arch:
9406 unsigned int saved_out_attr = out_attr->int_value();
9407 // Merge Tag_CPU_arch and Tag_also_compatible_with.
9408 int secondary_compat =
9409 this->get_secondary_compatible_arch(pasd);
9410 int secondary_compat_out =
9411 this->get_secondary_compatible_arch(
9412 this->attributes_section_data_);
9413 out_attr[i].set_int_value(
9414 tag_cpu_arch_combine(name, out_attr[i].int_value(),
9415 &secondary_compat_out,
9416 in_attr[i].int_value(),
9418 this->set_secondary_compatible_arch(this->attributes_section_data_,
9419 secondary_compat_out);
9421 // Merge Tag_CPU_name and Tag_CPU_raw_name.
9422 if (out_attr[i].int_value() == saved_out_attr)
9423 ; // Leave the names alone.
9424 else if (out_attr[i].int_value() == in_attr[i].int_value())
9426 // The output architecture has been changed to match the
9427 // input architecture. Use the input names.
9428 out_attr[elfcpp::Tag_CPU_name].set_string_value(
9429 in_attr[elfcpp::Tag_CPU_name].string_value());
9430 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
9431 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
9435 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
9436 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
9439 // If we still don't have a value for Tag_CPU_name,
9440 // make one up now. Tag_CPU_raw_name remains blank.
9441 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
9443 const std::string cpu_name =
9444 this->tag_cpu_name_value(out_attr[i].int_value());
9445 // FIXME: If we see an unknown CPU, this will be set
9446 // to "<unknown CPU n>", where n is the attribute value.
9447 // This is different from BFD, which leaves the name alone.
9448 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
9453 case elfcpp::Tag_ARM_ISA_use:
9454 case elfcpp::Tag_THUMB_ISA_use:
9455 case elfcpp::Tag_WMMX_arch:
9456 case elfcpp::Tag_Advanced_SIMD_arch:
9457 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
9458 case elfcpp::Tag_ABI_FP_rounding:
9459 case elfcpp::Tag_ABI_FP_exceptions:
9460 case elfcpp::Tag_ABI_FP_user_exceptions:
9461 case elfcpp::Tag_ABI_FP_number_model:
9462 case elfcpp::Tag_VFP_HP_extension:
9463 case elfcpp::Tag_CPU_unaligned_access:
9464 case elfcpp::Tag_T2EE_use:
9465 case elfcpp::Tag_Virtualization_use:
9466 case elfcpp::Tag_MPextension_use:
9467 // Use the largest value specified.
9468 if (in_attr[i].int_value() > out_attr[i].int_value())
9469 out_attr[i].set_int_value(in_attr[i].int_value());
9472 case elfcpp::Tag_ABI_align8_preserved:
9473 case elfcpp::Tag_ABI_PCS_RO_data:
9474 // Use the smallest value specified.
9475 if (in_attr[i].int_value() < out_attr[i].int_value())
9476 out_attr[i].set_int_value(in_attr[i].int_value());
9479 case elfcpp::Tag_ABI_align8_needed:
9480 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
9481 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
9482 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
9485 // This error message should be enabled once all non-conformant
9486 // binaries in the toolchain have had the attributes set
9488 // gold_error(_("output 8-byte data alignment conflicts with %s"),
9492 case elfcpp::Tag_ABI_FP_denormal:
9493 case elfcpp::Tag_ABI_PCS_GOT_use:
9495 // These tags have 0 = don't care, 1 = strong requirement,
9496 // 2 = weak requirement.
9497 static const int order_021[3] = {0, 2, 1};
9499 // Use the "greatest" from the sequence 0, 2, 1, or the largest
9500 // value if greater than 2 (for future-proofing).
9501 if ((in_attr[i].int_value() > 2
9502 && in_attr[i].int_value() > out_attr[i].int_value())
9503 || (in_attr[i].int_value() <= 2
9504 && out_attr[i].int_value() <= 2
9505 && (order_021[in_attr[i].int_value()]
9506 > order_021[out_attr[i].int_value()])))
9507 out_attr[i].set_int_value(in_attr[i].int_value());
9511 case elfcpp::Tag_CPU_arch_profile:
9512 if (out_attr[i].int_value() != in_attr[i].int_value())
9514 // 0 will merge with anything.
9515 // 'A' and 'S' merge to 'A'.
9516 // 'R' and 'S' merge to 'R'.
9517 // 'M' and 'A|R|S' is an error.
9518 if (out_attr[i].int_value() == 0
9519 || (out_attr[i].int_value() == 'S'
9520 && (in_attr[i].int_value() == 'A'
9521 || in_attr[i].int_value() == 'R')))
9522 out_attr[i].set_int_value(in_attr[i].int_value());
9523 else if (in_attr[i].int_value() == 0
9524 || (in_attr[i].int_value() == 'S'
9525 && (out_attr[i].int_value() == 'A'
9526 || out_attr[i].int_value() == 'R')))
9531 (_("conflicting architecture profiles %c/%c"),
9532 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
9533 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
9537 case elfcpp::Tag_VFP_arch:
9554 // Values greater than 6 aren't defined, so just pick the
9556 if (in_attr[i].int_value() > 6
9557 && in_attr[i].int_value() > out_attr[i].int_value())
9559 *out_attr = *in_attr;
9562 // The output uses the superset of input features
9563 // (ISA version) and registers.
9564 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
9565 vfp_versions[out_attr[i].int_value()].ver);
9566 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
9567 vfp_versions[out_attr[i].int_value()].regs);
9568 // This assumes all possible supersets are also a valid
9571 for (newval = 6; newval > 0; newval--)
9573 if (regs == vfp_versions[newval].regs
9574 && ver == vfp_versions[newval].ver)
9577 out_attr[i].set_int_value(newval);
9580 case elfcpp::Tag_PCS_config:
9581 if (out_attr[i].int_value() == 0)
9582 out_attr[i].set_int_value(in_attr[i].int_value());
9583 else if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9585 // It's sometimes ok to mix different configs, so this is only
9587 gold_warning(_("%s: conflicting platform configuration"), name);
9590 case elfcpp::Tag_ABI_PCS_R9_use:
9591 if (in_attr[i].int_value() != out_attr[i].int_value()
9592 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
9593 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused)
9595 gold_error(_("%s: conflicting use of R9"), name);
9597 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
9598 out_attr[i].set_int_value(in_attr[i].int_value());
9600 case elfcpp::Tag_ABI_PCS_RW_data:
9601 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
9602 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9603 != elfcpp::AEABI_R9_SB)
9604 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9605 != elfcpp::AEABI_R9_unused))
9607 gold_error(_("%s: SB relative addressing conflicts with use "
9611 // Use the smallest value specified.
9612 if (in_attr[i].int_value() < out_attr[i].int_value())
9613 out_attr[i].set_int_value(in_attr[i].int_value());
9615 case elfcpp::Tag_ABI_PCS_wchar_t:
9616 // FIXME: Make it possible to turn off this warning.
9617 if (out_attr[i].int_value()
9618 && in_attr[i].int_value()
9619 && out_attr[i].int_value() != in_attr[i].int_value())
9621 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
9622 "use %u-byte wchar_t; use of wchar_t values "
9623 "across objects may fail"),
9624 name, in_attr[i].int_value(),
9625 out_attr[i].int_value());
9627 else if (in_attr[i].int_value() && !out_attr[i].int_value())
9628 out_attr[i].set_int_value(in_attr[i].int_value());
9630 case elfcpp::Tag_ABI_enum_size:
9631 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
9633 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
9634 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
9636 // The existing object is compatible with anything.
9637 // Use whatever requirements the new object has.
9638 out_attr[i].set_int_value(in_attr[i].int_value());
9640 // FIXME: Make it possible to turn off this warning.
9641 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
9642 && out_attr[i].int_value() != in_attr[i].int_value())
9644 unsigned int in_value = in_attr[i].int_value();
9645 unsigned int out_value = out_attr[i].int_value();
9646 gold_warning(_("%s uses %s enums yet the output is to use "
9647 "%s enums; use of enum values across objects "
9650 this->aeabi_enum_name(in_value).c_str(),
9651 this->aeabi_enum_name(out_value).c_str());
9655 case elfcpp::Tag_ABI_VFP_args:
9658 case elfcpp::Tag_ABI_WMMX_args:
9659 if (in_attr[i].int_value() != out_attr[i].int_value())
9661 gold_error(_("%s uses iWMMXt register arguments, output does "
9666 case Object_attribute::Tag_compatibility:
9667 // Merged in target-independent code.
9669 case elfcpp::Tag_ABI_HardFP_use:
9670 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
9671 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
9672 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
9673 out_attr[i].set_int_value(3);
9674 else if (in_attr[i].int_value() > out_attr[i].int_value())
9675 out_attr[i].set_int_value(in_attr[i].int_value());
9677 case elfcpp::Tag_ABI_FP_16bit_format:
9678 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9680 if (in_attr[i].int_value() != out_attr[i].int_value())
9681 gold_error(_("fp16 format mismatch between %s and output"),
9684 if (in_attr[i].int_value() != 0)
9685 out_attr[i].set_int_value(in_attr[i].int_value());
9688 case elfcpp::Tag_nodefaults:
9689 // This tag is set if it exists, but the value is unused (and is
9690 // typically zero). We don't actually need to do anything here -
9691 // the merge happens automatically when the type flags are merged
9694 case elfcpp::Tag_also_compatible_with:
9695 // Already done in Tag_CPU_arch.
9697 case elfcpp::Tag_conformance:
9698 // Keep the attribute if it matches. Throw it away otherwise.
9699 // No attribute means no claim to conform.
9700 if (in_attr[i].string_value() != out_attr[i].string_value())
9701 out_attr[i].set_string_value("");
9706 const char* err_object = NULL;
9708 // The "known_obj_attributes" table does contain some undefined
9709 // attributes. Ensure that there are unused.
9710 if (out_attr[i].int_value() != 0
9711 || out_attr[i].string_value() != "")
9712 err_object = "output";
9713 else if (in_attr[i].int_value() != 0
9714 || in_attr[i].string_value() != "")
9717 if (err_object != NULL)
9719 // Attribute numbers >=64 (mod 128) can be safely ignored.
9721 gold_error(_("%s: unknown mandatory EABI object attribute "
9725 gold_warning(_("%s: unknown EABI object attribute %d"),
9729 // Only pass on attributes that match in both inputs.
9730 if (!in_attr[i].matches(out_attr[i]))
9732 out_attr[i].set_int_value(0);
9733 out_attr[i].set_string_value("");
9738 // If out_attr was copied from in_attr then it won't have a type yet.
9739 if (in_attr[i].type() && !out_attr[i].type())
9740 out_attr[i].set_type(in_attr[i].type());
9743 // Merge Tag_compatibility attributes and any common GNU ones.
9744 this->attributes_section_data_->merge(name, pasd);
9746 // Check for any attributes not known on ARM.
9747 typedef Vendor_object_attributes::Other_attributes Other_attributes;
9748 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
9749 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
9750 Other_attributes* out_other_attributes =
9751 this->attributes_section_data_->other_attributes(vendor);
9752 Other_attributes::iterator out_iter = out_other_attributes->begin();
9754 while (in_iter != in_other_attributes->end()
9755 || out_iter != out_other_attributes->end())
9757 const char* err_object = NULL;
9760 // The tags for each list are in numerical order.
9761 // If the tags are equal, then merge.
9762 if (out_iter != out_other_attributes->end()
9763 && (in_iter == in_other_attributes->end()
9764 || in_iter->first > out_iter->first))
9766 // This attribute only exists in output. We can't merge, and we
9767 // don't know what the tag means, so delete it.
9768 err_object = "output";
9769 err_tag = out_iter->first;
9770 int saved_tag = out_iter->first;
9771 delete out_iter->second;
9772 out_other_attributes->erase(out_iter);
9773 out_iter = out_other_attributes->upper_bound(saved_tag);
9775 else if (in_iter != in_other_attributes->end()
9776 && (out_iter != out_other_attributes->end()
9777 || in_iter->first < out_iter->first))
9779 // This attribute only exists in input. We can't merge, and we
9780 // don't know what the tag means, so ignore it.
9782 err_tag = in_iter->first;
9785 else // The tags are equal.
9787 // As present, all attributes in the list are unknown, and
9788 // therefore can't be merged meaningfully.
9789 err_object = "output";
9790 err_tag = out_iter->first;
9792 // Only pass on attributes that match in both inputs.
9793 if (!in_iter->second->matches(*(out_iter->second)))
9795 // No match. Delete the attribute.
9796 int saved_tag = out_iter->first;
9797 delete out_iter->second;
9798 out_other_attributes->erase(out_iter);
9799 out_iter = out_other_attributes->upper_bound(saved_tag);
9803 // Matched. Keep the attribute and move to the next.
9811 // Attribute numbers >=64 (mod 128) can be safely ignored. */
9812 if ((err_tag & 127) < 64)
9814 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
9815 err_object, err_tag);
9819 gold_warning(_("%s: unknown EABI object attribute %d"),
9820 err_object, err_tag);
9826 // Stub-generation methods for Target_arm.
9828 // Make a new Arm_input_section object.
9830 template<bool big_endian>
9831 Arm_input_section<big_endian>*
9832 Target_arm<big_endian>::new_arm_input_section(
9836 Section_id sid(relobj, shndx);
9838 Arm_input_section<big_endian>* arm_input_section =
9839 new Arm_input_section<big_endian>(relobj, shndx);
9840 arm_input_section->init();
9842 // Register new Arm_input_section in map for look-up.
9843 std::pair<typename Arm_input_section_map::iterator, bool> ins =
9844 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
9846 // Make sure that it we have not created another Arm_input_section
9847 // for this input section already.
9848 gold_assert(ins.second);
9850 return arm_input_section;
9853 // Find the Arm_input_section object corresponding to the SHNDX-th input
9854 // section of RELOBJ.
9856 template<bool big_endian>
9857 Arm_input_section<big_endian>*
9858 Target_arm<big_endian>::find_arm_input_section(
9860 unsigned int shndx) const
9862 Section_id sid(relobj, shndx);
9863 typename Arm_input_section_map::const_iterator p =
9864 this->arm_input_section_map_.find(sid);
9865 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
9868 // Make a new stub table.
9870 template<bool big_endian>
9871 Stub_table<big_endian>*
9872 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
9874 Stub_table<big_endian>* stub_table =
9875 new Stub_table<big_endian>(owner);
9876 this->stub_tables_.push_back(stub_table);
9878 stub_table->set_address(owner->address() + owner->data_size());
9879 stub_table->set_file_offset(owner->offset() + owner->data_size());
9880 stub_table->finalize_data_size();
9885 // Scan a relocation for stub generation.
9887 template<bool big_endian>
9889 Target_arm<big_endian>::scan_reloc_for_stub(
9890 const Relocate_info<32, big_endian>* relinfo,
9891 unsigned int r_type,
9892 const Sized_symbol<32>* gsym,
9894 const Symbol_value<32>* psymval,
9895 elfcpp::Elf_types<32>::Elf_Swxword addend,
9896 Arm_address address)
9898 typedef typename Target_arm<big_endian>::Relocate Relocate;
9900 const Arm_relobj<big_endian>* arm_relobj =
9901 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9903 bool target_is_thumb;
9904 Symbol_value<32> symval;
9907 // This is a global symbol. Determine if we use PLT and if the
9908 // final target is THUMB.
9909 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
9911 // This uses a PLT, change the symbol value.
9912 symval.set_output_value(this->plt_section()->address()
9913 + gsym->plt_offset());
9915 target_is_thumb = false;
9917 else if (gsym->is_undefined())
9918 // There is no need to generate a stub symbol is undefined.
9923 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
9924 || (gsym->type() == elfcpp::STT_FUNC
9925 && !gsym->is_undefined()
9926 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
9931 // This is a local symbol. Determine if the final target is THUMB.
9932 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
9935 // Strip LSB if this points to a THUMB target.
9936 const Arm_reloc_property* reloc_property =
9937 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9938 gold_assert(reloc_property != NULL);
9940 && reloc_property->uses_thumb_bit()
9941 && ((psymval->value(arm_relobj, 0) & 1) != 0))
9943 Arm_address stripped_value =
9944 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
9945 symval.set_output_value(stripped_value);
9949 // Get the symbol value.
9950 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
9952 // Owing to pipelining, the PC relative branches below actually skip
9953 // two instructions when the branch offset is 0.
9954 Arm_address destination;
9957 case elfcpp::R_ARM_CALL:
9958 case elfcpp::R_ARM_JUMP24:
9959 case elfcpp::R_ARM_PLT32:
9961 destination = value + addend + 8;
9963 case elfcpp::R_ARM_THM_CALL:
9964 case elfcpp::R_ARM_THM_XPC22:
9965 case elfcpp::R_ARM_THM_JUMP24:
9966 case elfcpp::R_ARM_THM_JUMP19:
9968 destination = value + addend + 4;
9974 Reloc_stub* stub = NULL;
9975 Stub_type stub_type =
9976 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
9978 if (stub_type != arm_stub_none)
9980 // Try looking up an existing stub from a stub table.
9981 Stub_table<big_endian>* stub_table =
9982 arm_relobj->stub_table(relinfo->data_shndx);
9983 gold_assert(stub_table != NULL);
9985 // Locate stub by destination.
9986 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
9988 // Create a stub if there is not one already
9989 stub = stub_table->find_reloc_stub(stub_key);
9992 // create a new stub and add it to stub table.
9993 stub = this->stub_factory().make_reloc_stub(stub_type);
9994 stub_table->add_reloc_stub(stub, stub_key);
9997 // Record the destination address.
9998 stub->set_destination_address(destination
9999 | (target_is_thumb ? 1 : 0));
10002 // For Cortex-A8, we need to record a relocation at 4K page boundary.
10003 if (this->fix_cortex_a8_
10004 && (r_type == elfcpp::R_ARM_THM_JUMP24
10005 || r_type == elfcpp::R_ARM_THM_JUMP19
10006 || r_type == elfcpp::R_ARM_THM_CALL
10007 || r_type == elfcpp::R_ARM_THM_XPC22)
10008 && (address & 0xfffU) == 0xffeU)
10010 // Found a candidate. Note we haven't checked the destination is
10011 // within 4K here: if we do so (and don't create a record) we can't
10012 // tell that a branch should have been relocated when scanning later.
10013 this->cortex_a8_relocs_info_[address] =
10014 new Cortex_a8_reloc(stub, r_type,
10015 destination | (target_is_thumb ? 1 : 0));
10019 // This function scans a relocation sections for stub generation.
10020 // The template parameter Relocate must be a class type which provides
10021 // a single function, relocate(), which implements the machine
10022 // specific part of a relocation.
10024 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
10025 // SHT_REL or SHT_RELA.
10027 // PRELOCS points to the relocation data. RELOC_COUNT is the number
10028 // of relocs. OUTPUT_SECTION is the output section.
10029 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
10030 // mapped to output offsets.
10032 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
10033 // VIEW_SIZE is the size. These refer to the input section, unless
10034 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
10035 // the output section.
10037 template<bool big_endian>
10038 template<int sh_type>
10040 Target_arm<big_endian>::scan_reloc_section_for_stubs(
10041 const Relocate_info<32, big_endian>* relinfo,
10042 const unsigned char* prelocs,
10043 size_t reloc_count,
10044 Output_section* output_section,
10045 bool needs_special_offset_handling,
10046 const unsigned char* view,
10047 elfcpp::Elf_types<32>::Elf_Addr view_address,
10050 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
10051 const int reloc_size =
10052 Reloc_types<sh_type, 32, big_endian>::reloc_size;
10054 Arm_relobj<big_endian>* arm_object =
10055 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10056 unsigned int local_count = arm_object->local_symbol_count();
10058 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
10060 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
10062 Reltype reloc(prelocs);
10064 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
10065 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
10066 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
10068 r_type = this->get_real_reloc_type(r_type);
10070 // Only a few relocation types need stubs.
10071 if ((r_type != elfcpp::R_ARM_CALL)
10072 && (r_type != elfcpp::R_ARM_JUMP24)
10073 && (r_type != elfcpp::R_ARM_PLT32)
10074 && (r_type != elfcpp::R_ARM_THM_CALL)
10075 && (r_type != elfcpp::R_ARM_THM_XPC22)
10076 && (r_type != elfcpp::R_ARM_THM_JUMP24)
10077 && (r_type != elfcpp::R_ARM_THM_JUMP19)
10078 && (r_type != elfcpp::R_ARM_V4BX))
10081 section_offset_type offset =
10082 convert_to_section_size_type(reloc.get_r_offset());
10084 if (needs_special_offset_handling)
10086 offset = output_section->output_offset(relinfo->object,
10087 relinfo->data_shndx,
10093 // Create a v4bx stub if --fix-v4bx-interworking is used.
10094 if (r_type == elfcpp::R_ARM_V4BX)
10096 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
10098 // Get the BX instruction.
10099 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
10100 const Valtype* wv =
10101 reinterpret_cast<const Valtype*>(view + offset);
10102 elfcpp::Elf_types<32>::Elf_Swxword insn =
10103 elfcpp::Swap<32, big_endian>::readval(wv);
10104 const uint32_t reg = (insn & 0xf);
10108 // Try looking up an existing stub from a stub table.
10109 Stub_table<big_endian>* stub_table =
10110 arm_object->stub_table(relinfo->data_shndx);
10111 gold_assert(stub_table != NULL);
10113 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
10115 // create a new stub and add it to stub table.
10116 Arm_v4bx_stub* stub =
10117 this->stub_factory().make_arm_v4bx_stub(reg);
10118 gold_assert(stub != NULL);
10119 stub_table->add_arm_v4bx_stub(stub);
10127 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
10128 elfcpp::Elf_types<32>::Elf_Swxword addend =
10129 stub_addend_reader(r_type, view + offset, reloc);
10131 const Sized_symbol<32>* sym;
10133 Symbol_value<32> symval;
10134 const Symbol_value<32> *psymval;
10135 if (r_sym < local_count)
10138 psymval = arm_object->local_symbol(r_sym);
10140 // If the local symbol belongs to a section we are discarding,
10141 // and that section is a debug section, try to find the
10142 // corresponding kept section and map this symbol to its
10143 // counterpart in the kept section. The symbol must not
10144 // correspond to a section we are folding.
10146 unsigned int shndx = psymval->input_shndx(&is_ordinary);
10148 && shndx != elfcpp::SHN_UNDEF
10149 && !arm_object->is_section_included(shndx)
10150 && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
10152 if (comdat_behavior == CB_UNDETERMINED)
10155 arm_object->section_name(relinfo->data_shndx);
10156 comdat_behavior = get_comdat_behavior(name.c_str());
10158 if (comdat_behavior == CB_PRETEND)
10161 typename elfcpp::Elf_types<32>::Elf_Addr value =
10162 arm_object->map_to_kept_section(shndx, &found);
10164 symval.set_output_value(value + psymval->input_value());
10166 symval.set_output_value(0);
10170 symval.set_output_value(0);
10172 symval.set_no_output_symtab_entry();
10178 const Symbol* gsym = arm_object->global_symbol(r_sym);
10179 gold_assert(gsym != NULL);
10180 if (gsym->is_forwarder())
10181 gsym = relinfo->symtab->resolve_forwards(gsym);
10183 sym = static_cast<const Sized_symbol<32>*>(gsym);
10184 if (sym->has_symtab_index())
10185 symval.set_output_symtab_index(sym->symtab_index());
10187 symval.set_no_output_symtab_entry();
10189 // We need to compute the would-be final value of this global
10191 const Symbol_table* symtab = relinfo->symtab;
10192 const Sized_symbol<32>* sized_symbol =
10193 symtab->get_sized_symbol<32>(gsym);
10194 Symbol_table::Compute_final_value_status status;
10195 Arm_address value =
10196 symtab->compute_final_value<32>(sized_symbol, &status);
10198 // Skip this if the symbol has not output section.
10199 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
10202 symval.set_output_value(value);
10206 // If symbol is a section symbol, we don't know the actual type of
10207 // destination. Give up.
10208 if (psymval->is_section_symbol())
10211 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
10212 addend, view_address + offset);
10216 // Scan an input section for stub generation.
10218 template<bool big_endian>
10220 Target_arm<big_endian>::scan_section_for_stubs(
10221 const Relocate_info<32, big_endian>* relinfo,
10222 unsigned int sh_type,
10223 const unsigned char* prelocs,
10224 size_t reloc_count,
10225 Output_section* output_section,
10226 bool needs_special_offset_handling,
10227 const unsigned char* view,
10228 Arm_address view_address,
10229 section_size_type view_size)
10231 if (sh_type == elfcpp::SHT_REL)
10232 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
10237 needs_special_offset_handling,
10241 else if (sh_type == elfcpp::SHT_RELA)
10242 // We do not support RELA type relocations yet. This is provided for
10244 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
10249 needs_special_offset_handling,
10254 gold_unreachable();
10257 // Group input sections for stub generation.
10259 // We goup input sections in an output sections so that the total size,
10260 // including any padding space due to alignment is smaller than GROUP_SIZE
10261 // unless the only input section in group is bigger than GROUP_SIZE already.
10262 // Then an ARM stub table is created to follow the last input section
10263 // in group. For each group an ARM stub table is created an is placed
10264 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
10265 // extend the group after the stub table.
10267 template<bool big_endian>
10269 Target_arm<big_endian>::group_sections(
10271 section_size_type group_size,
10272 bool stubs_always_after_branch)
10274 // Group input sections and insert stub table
10275 Layout::Section_list section_list;
10276 layout->get_allocated_sections(§ion_list);
10277 for (Layout::Section_list::const_iterator p = section_list.begin();
10278 p != section_list.end();
10281 Arm_output_section<big_endian>* output_section =
10282 Arm_output_section<big_endian>::as_arm_output_section(*p);
10283 output_section->group_sections(group_size, stubs_always_after_branch,
10288 // Relaxation hook. This is where we do stub generation.
10290 template<bool big_endian>
10292 Target_arm<big_endian>::do_relax(
10294 const Input_objects* input_objects,
10295 Symbol_table* symtab,
10298 // No need to generate stubs if this is a relocatable link.
10299 gold_assert(!parameters->options().relocatable());
10301 // If this is the first pass, we need to group input sections into
10303 bool done_exidx_fixup = false;
10306 // Determine the stub group size. The group size is the absolute
10307 // value of the parameter --stub-group-size. If --stub-group-size
10308 // is passed a negative value, we restict stubs to be always after
10309 // the stubbed branches.
10310 int32_t stub_group_size_param =
10311 parameters->options().stub_group_size();
10312 bool stubs_always_after_branch = stub_group_size_param < 0;
10313 section_size_type stub_group_size = abs(stub_group_size_param);
10315 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
10316 // page as the first half of a 32-bit branch straddling two 4K pages.
10317 // This is a crude way of enforcing that.
10318 if (this->fix_cortex_a8_)
10319 stubs_always_after_branch = true;
10321 if (stub_group_size == 1)
10324 // Thumb branch range is +-4MB has to be used as the default
10325 // maximum size (a given section can contain both ARM and Thumb
10326 // code, so the worst case has to be taken into account). If we are
10327 // fixing cortex-a8 errata, the branch range has to be even smaller,
10328 // since wide conditional branch has a range of +-1MB only.
10330 // This value is 24K less than that, which allows for 2025
10331 // 12-byte stubs. If we exceed that, then we will fail to link.
10332 // The user will have to relink with an explicit group size
10334 if (this->fix_cortex_a8_)
10335 stub_group_size = 1024276;
10337 stub_group_size = 4170000;
10340 group_sections(layout, stub_group_size, stubs_always_after_branch);
10342 // Also fix .ARM.exidx section coverage.
10343 Output_section* os = layout->find_output_section(".ARM.exidx");
10344 if (os != NULL && os->type() == elfcpp::SHT_ARM_EXIDX)
10346 Arm_output_section<big_endian>* exidx_output_section =
10347 Arm_output_section<big_endian>::as_arm_output_section(os);
10348 this->fix_exidx_coverage(layout, exidx_output_section, symtab);
10349 done_exidx_fixup = true;
10353 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
10354 // beginning of each relaxation pass, just blow away all the stubs.
10355 // Alternatively, we could selectively remove only the stubs and reloc
10356 // information for code sections that have moved since the last pass.
10357 // That would require more book-keeping.
10358 typedef typename Stub_table_list::iterator Stub_table_iterator;
10359 if (this->fix_cortex_a8_)
10361 // Clear all Cortex-A8 reloc information.
10362 for (typename Cortex_a8_relocs_info::const_iterator p =
10363 this->cortex_a8_relocs_info_.begin();
10364 p != this->cortex_a8_relocs_info_.end();
10367 this->cortex_a8_relocs_info_.clear();
10369 // Remove all Cortex-A8 stubs.
10370 for (Stub_table_iterator sp = this->stub_tables_.begin();
10371 sp != this->stub_tables_.end();
10373 (*sp)->remove_all_cortex_a8_stubs();
10376 // Scan relocs for relocation stubs
10377 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10378 op != input_objects->relobj_end();
10381 Arm_relobj<big_endian>* arm_relobj =
10382 Arm_relobj<big_endian>::as_arm_relobj(*op);
10383 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
10386 // Check all stub tables to see if any of them have their data sizes
10387 // or addresses alignments changed. These are the only things that
10389 bool any_stub_table_changed = false;
10390 Unordered_set<const Output_section*> sections_needing_adjustment;
10391 for (Stub_table_iterator sp = this->stub_tables_.begin();
10392 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10395 if ((*sp)->update_data_size_and_addralign())
10397 // Update data size of stub table owner.
10398 Arm_input_section<big_endian>* owner = (*sp)->owner();
10399 uint64_t address = owner->address();
10400 off_t offset = owner->offset();
10401 owner->reset_address_and_file_offset();
10402 owner->set_address_and_file_offset(address, offset);
10404 sections_needing_adjustment.insert(owner->output_section());
10405 any_stub_table_changed = true;
10409 // Output_section_data::output_section() returns a const pointer but we
10410 // need to update output sections, so we record all output sections needing
10411 // update above and scan the sections here to find out what sections need
10413 for(Layout::Section_list::const_iterator p = layout->section_list().begin();
10414 p != layout->section_list().end();
10417 if (sections_needing_adjustment.find(*p)
10418 != sections_needing_adjustment.end())
10419 (*p)->set_section_offsets_need_adjustment();
10422 // Stop relaxation if no EXIDX fix-up and no stub table change.
10423 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
10425 // Finalize the stubs in the last relaxation pass.
10426 if (!continue_relaxation)
10428 for (Stub_table_iterator sp = this->stub_tables_.begin();
10429 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10431 (*sp)->finalize_stubs();
10433 // Update output local symbol counts of objects if necessary.
10434 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10435 op != input_objects->relobj_end();
10438 Arm_relobj<big_endian>* arm_relobj =
10439 Arm_relobj<big_endian>::as_arm_relobj(*op);
10441 // Update output local symbol counts. We need to discard local
10442 // symbols defined in parts of input sections that are discarded by
10444 if (arm_relobj->output_local_symbol_count_needs_update())
10445 arm_relobj->update_output_local_symbol_count();
10449 return continue_relaxation;
10452 // Relocate a stub.
10454 template<bool big_endian>
10456 Target_arm<big_endian>::relocate_stub(
10458 const Relocate_info<32, big_endian>* relinfo,
10459 Output_section* output_section,
10460 unsigned char* view,
10461 Arm_address address,
10462 section_size_type view_size)
10465 const Stub_template* stub_template = stub->stub_template();
10466 for (size_t i = 0; i < stub_template->reloc_count(); i++)
10468 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
10469 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
10471 unsigned int r_type = insn->r_type();
10472 section_size_type reloc_offset = stub_template->reloc_offset(i);
10473 section_size_type reloc_size = insn->size();
10474 gold_assert(reloc_offset + reloc_size <= view_size);
10476 // This is the address of the stub destination.
10477 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
10478 Symbol_value<32> symval;
10479 symval.set_output_value(target);
10481 // Synthesize a fake reloc just in case. We don't have a symbol so
10483 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
10484 memset(reloc_buffer, 0, sizeof(reloc_buffer));
10485 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
10486 reloc_write.put_r_offset(reloc_offset);
10487 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
10488 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
10490 relocate.relocate(relinfo, this, output_section,
10491 this->fake_relnum_for_stubs, rel, r_type,
10492 NULL, &symval, view + reloc_offset,
10493 address + reloc_offset, reloc_size);
10497 // Determine whether an object attribute tag takes an integer, a
10500 template<bool big_endian>
10502 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
10504 if (tag == Object_attribute::Tag_compatibility)
10505 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10506 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
10507 else if (tag == elfcpp::Tag_nodefaults)
10508 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10509 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
10510 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
10511 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
10513 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
10515 return ((tag & 1) != 0
10516 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
10517 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
10520 // Reorder attributes.
10522 // The ABI defines that Tag_conformance should be emitted first, and that
10523 // Tag_nodefaults should be second (if either is defined). This sets those
10524 // two positions, and bumps up the position of all the remaining tags to
10527 template<bool big_endian>
10529 Target_arm<big_endian>::do_attributes_order(int num) const
10531 // Reorder the known object attributes in output. We want to move
10532 // Tag_conformance to position 4 and Tag_conformance to position 5
10533 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
10535 return elfcpp::Tag_conformance;
10537 return elfcpp::Tag_nodefaults;
10538 if ((num - 2) < elfcpp::Tag_nodefaults)
10540 if ((num - 1) < elfcpp::Tag_conformance)
10545 // Scan a span of THUMB code for Cortex-A8 erratum.
10547 template<bool big_endian>
10549 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
10550 Arm_relobj<big_endian>* arm_relobj,
10551 unsigned int shndx,
10552 section_size_type span_start,
10553 section_size_type span_end,
10554 const unsigned char* view,
10555 Arm_address address)
10557 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
10559 // The opcode is BLX.W, BL.W, B.W, Bcc.W
10560 // The branch target is in the same 4KB region as the
10561 // first half of the branch.
10562 // The instruction before the branch is a 32-bit
10563 // length non-branch instruction.
10564 section_size_type i = span_start;
10565 bool last_was_32bit = false;
10566 bool last_was_branch = false;
10567 while (i < span_end)
10569 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10570 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
10571 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
10572 bool is_blx = false, is_b = false;
10573 bool is_bl = false, is_bcc = false;
10575 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
10578 // Load the rest of the insn (in manual-friendly order).
10579 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
10581 // Encoding T4: B<c>.W.
10582 is_b = (insn & 0xf800d000U) == 0xf0009000U;
10583 // Encoding T1: BL<c>.W.
10584 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
10585 // Encoding T2: BLX<c>.W.
10586 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
10587 // Encoding T3: B<c>.W (not permitted in IT block).
10588 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
10589 && (insn & 0x07f00000U) != 0x03800000U);
10592 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
10594 // If this instruction is a 32-bit THUMB branch that crosses a 4K
10595 // page boundary and it follows 32-bit non-branch instruction,
10596 // we need to work around.
10597 if (is_32bit_branch
10598 && ((address + i) & 0xfffU) == 0xffeU
10600 && !last_was_branch)
10602 // Check to see if there is a relocation stub for this branch.
10603 bool force_target_arm = false;
10604 bool force_target_thumb = false;
10605 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
10606 Cortex_a8_relocs_info::const_iterator p =
10607 this->cortex_a8_relocs_info_.find(address + i);
10609 if (p != this->cortex_a8_relocs_info_.end())
10611 cortex_a8_reloc = p->second;
10612 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
10614 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10615 && !target_is_thumb)
10616 force_target_arm = true;
10617 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10618 && target_is_thumb)
10619 force_target_thumb = true;
10623 Stub_type stub_type = arm_stub_none;
10625 // Check if we have an offending branch instruction.
10626 uint16_t upper_insn = (insn >> 16) & 0xffffU;
10627 uint16_t lower_insn = insn & 0xffffU;
10628 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10630 if (cortex_a8_reloc != NULL
10631 && cortex_a8_reloc->reloc_stub() != NULL)
10632 // We've already made a stub for this instruction, e.g.
10633 // it's a long branch or a Thumb->ARM stub. Assume that
10634 // stub will suffice to work around the A8 erratum (see
10635 // setting of always_after_branch above).
10639 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
10641 stub_type = arm_stub_a8_veneer_b_cond;
10643 else if (is_b || is_bl || is_blx)
10645 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
10650 stub_type = (is_blx
10651 ? arm_stub_a8_veneer_blx
10653 ? arm_stub_a8_veneer_bl
10654 : arm_stub_a8_veneer_b));
10657 if (stub_type != arm_stub_none)
10659 Arm_address pc_for_insn = address + i + 4;
10661 // The original instruction is a BL, but the target is
10662 // an ARM instruction. If we were not making a stub,
10663 // the BL would have been converted to a BLX. Use the
10664 // BLX stub instead in that case.
10665 if (this->may_use_blx() && force_target_arm
10666 && stub_type == arm_stub_a8_veneer_bl)
10668 stub_type = arm_stub_a8_veneer_blx;
10672 // Conversely, if the original instruction was
10673 // BLX but the target is Thumb mode, use the BL stub.
10674 else if (force_target_thumb
10675 && stub_type == arm_stub_a8_veneer_blx)
10677 stub_type = arm_stub_a8_veneer_bl;
10685 // If we found a relocation, use the proper destination,
10686 // not the offset in the (unrelocated) instruction.
10687 // Note this is always done if we switched the stub type above.
10688 if (cortex_a8_reloc != NULL)
10689 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
10691 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
10693 // Add a new stub if destination address in in the same page.
10694 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
10696 Cortex_a8_stub* stub =
10697 this->stub_factory_.make_cortex_a8_stub(stub_type,
10701 Stub_table<big_endian>* stub_table =
10702 arm_relobj->stub_table(shndx);
10703 gold_assert(stub_table != NULL);
10704 stub_table->add_cortex_a8_stub(address + i, stub);
10709 i += insn_32bit ? 4 : 2;
10710 last_was_32bit = insn_32bit;
10711 last_was_branch = is_32bit_branch;
10715 // Apply the Cortex-A8 workaround.
10717 template<bool big_endian>
10719 Target_arm<big_endian>::apply_cortex_a8_workaround(
10720 const Cortex_a8_stub* stub,
10721 Arm_address stub_address,
10722 unsigned char* insn_view,
10723 Arm_address insn_address)
10725 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10726 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
10727 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
10728 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
10729 off_t branch_offset = stub_address - (insn_address + 4);
10731 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10732 switch (stub->stub_template()->type())
10734 case arm_stub_a8_veneer_b_cond:
10735 gold_assert(!utils::has_overflow<21>(branch_offset));
10736 upper_insn = RelocFuncs::thumb32_cond_branch_upper(upper_insn,
10738 lower_insn = RelocFuncs::thumb32_cond_branch_lower(lower_insn,
10742 case arm_stub_a8_veneer_b:
10743 case arm_stub_a8_veneer_bl:
10744 case arm_stub_a8_veneer_blx:
10745 if ((lower_insn & 0x5000U) == 0x4000U)
10746 // For a BLX instruction, make sure that the relocation is
10747 // rounded up to a word boundary. This follows the semantics of
10748 // the instruction which specifies that bit 1 of the target
10749 // address will come from bit 1 of the base address.
10750 branch_offset = (branch_offset + 2) & ~3;
10752 // Put BRANCH_OFFSET back into the insn.
10753 gold_assert(!utils::has_overflow<25>(branch_offset));
10754 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
10755 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
10759 gold_unreachable();
10762 // Put the relocated value back in the object file:
10763 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
10764 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
10767 template<bool big_endian>
10768 class Target_selector_arm : public Target_selector
10771 Target_selector_arm()
10772 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
10773 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
10777 do_instantiate_target()
10778 { return new Target_arm<big_endian>(); }
10781 // Fix .ARM.exidx section coverage.
10783 template<bool big_endian>
10785 Target_arm<big_endian>::fix_exidx_coverage(
10787 Arm_output_section<big_endian>* exidx_section,
10788 Symbol_table* symtab)
10790 // We need to look at all the input sections in output in ascending
10791 // order of of output address. We do that by building a sorted list
10792 // of output sections by addresses. Then we looks at the output sections
10793 // in order. The input sections in an output section are already sorted
10794 // by addresses within the output section.
10796 typedef std::set<Output_section*, output_section_address_less_than>
10797 Sorted_output_section_list;
10798 Sorted_output_section_list sorted_output_sections;
10799 Layout::Section_list section_list;
10800 layout->get_allocated_sections(§ion_list);
10801 for (Layout::Section_list::const_iterator p = section_list.begin();
10802 p != section_list.end();
10805 // We only care about output sections that contain executable code.
10806 if (((*p)->flags() & elfcpp::SHF_EXECINSTR) != 0)
10807 sorted_output_sections.insert(*p);
10810 // Go over the output sections in ascending order of output addresses.
10811 typedef typename Arm_output_section<big_endian>::Text_section_list
10813 Text_section_list sorted_text_sections;
10814 for(typename Sorted_output_section_list::iterator p =
10815 sorted_output_sections.begin();
10816 p != sorted_output_sections.end();
10819 Arm_output_section<big_endian>* arm_output_section =
10820 Arm_output_section<big_endian>::as_arm_output_section(*p);
10821 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
10824 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab);
10827 Target_selector_arm<false> target_selector_arm;
10828 Target_selector_arm<true> target_selector_armbe;
10830 } // End anonymous namespace.