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 endianness-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 endianness.
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); }
1167 // Return the original size of the section.
1169 original_size() const
1170 { return this->original_size_; }
1173 // Write data to output file.
1175 do_write(Output_file*);
1177 // Return required alignment of this.
1179 do_addralign() const
1181 if (this->is_stub_table_owner())
1182 return std::max(this->stub_table_->addralign(),
1183 static_cast<uint64_t>(this->original_addralign_));
1185 return this->original_addralign_;
1188 // Finalize data size.
1190 set_final_data_size();
1192 // Reset address and file offset.
1194 do_reset_address_and_file_offset();
1198 do_output_offset(const Relobj* object, unsigned int shndx,
1199 section_offset_type offset,
1200 section_offset_type* poutput) const
1202 if ((object == this->relobj())
1203 && (shndx == this->shndx())
1206 convert_types<section_offset_type, uint32_t>(this->original_size_)))
1216 // Copying is not allowed.
1217 Arm_input_section(const Arm_input_section&);
1218 Arm_input_section& operator=(const Arm_input_section&);
1220 // Address alignment of the original input section.
1221 uint32_t original_addralign_;
1222 // Section size of the original input section.
1223 uint32_t original_size_;
1225 Stub_table<big_endian>* stub_table_;
1228 // Arm_exidx_fixup class. This is used to define a number of methods
1229 // and keep states for fixing up EXIDX coverage.
1231 class Arm_exidx_fixup
1234 Arm_exidx_fixup(Output_section* exidx_output_section,
1235 bool merge_exidx_entries = true)
1236 : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
1237 last_inlined_entry_(0), last_input_section_(NULL),
1238 section_offset_map_(NULL), first_output_text_section_(NULL),
1239 merge_exidx_entries_(merge_exidx_entries)
1243 { delete this->section_offset_map_; }
1245 // Process an EXIDX section for entry merging. Return number of bytes to
1246 // be deleted in output. If parts of the input EXIDX section are merged
1247 // a heap allocated Arm_exidx_section_offset_map is store in the located
1248 // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
1250 template<bool big_endian>
1252 process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
1253 Arm_exidx_section_offset_map** psection_offset_map);
1255 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1256 // input section, if there is not one already.
1258 add_exidx_cantunwind_as_needed();
1260 // Return the output section for the text section which is linked to the
1261 // first exidx input in output.
1263 first_output_text_section() const
1264 { return this->first_output_text_section_; }
1267 // Copying is not allowed.
1268 Arm_exidx_fixup(const Arm_exidx_fixup&);
1269 Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
1271 // Type of EXIDX unwind entry.
1276 // EXIDX_CANTUNWIND.
1277 UT_EXIDX_CANTUNWIND,
1284 // Process an EXIDX entry. We only care about the second word of the
1285 // entry. Return true if the entry can be deleted.
1287 process_exidx_entry(uint32_t second_word);
1289 // Update the current section offset map during EXIDX section fix-up.
1290 // If there is no map, create one. INPUT_OFFSET is the offset of a
1291 // reference point, DELETED_BYTES is the number of deleted by in the
1292 // section so far. If DELETE_ENTRY is true, the reference point and
1293 // all offsets after the previous reference point are discarded.
1295 update_offset_map(section_offset_type input_offset,
1296 section_size_type deleted_bytes, bool delete_entry);
1298 // EXIDX output section.
1299 Output_section* exidx_output_section_;
1300 // Unwind type of the last EXIDX entry processed.
1301 Unwind_type last_unwind_type_;
1302 // Last seen inlined EXIDX entry.
1303 uint32_t last_inlined_entry_;
1304 // Last processed EXIDX input section.
1305 const Arm_exidx_input_section* last_input_section_;
1306 // Section offset map created in process_exidx_section.
1307 Arm_exidx_section_offset_map* section_offset_map_;
1308 // Output section for the text section which is linked to the first exidx
1310 Output_section* first_output_text_section_;
1312 bool merge_exidx_entries_;
1315 // Arm output section class. This is defined mainly to add a number of
1316 // stub generation methods.
1318 template<bool big_endian>
1319 class Arm_output_section : public Output_section
1322 typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
1324 Arm_output_section(const char* name, elfcpp::Elf_Word type,
1325 elfcpp::Elf_Xword flags)
1326 : Output_section(name, type, flags)
1328 if (type == elfcpp::SHT_ARM_EXIDX)
1329 this->set_always_keeps_input_sections();
1332 ~Arm_output_section()
1335 // Group input sections for stub generation.
1337 group_sections(section_size_type, bool, Target_arm<big_endian>*);
1339 // Downcast a base pointer to an Arm_output_section pointer. This is
1340 // not type-safe but we only use Arm_output_section not the base class.
1341 static Arm_output_section<big_endian>*
1342 as_arm_output_section(Output_section* os)
1343 { return static_cast<Arm_output_section<big_endian>*>(os); }
1345 // Append all input text sections in this into LIST.
1347 append_text_sections_to_list(Text_section_list* list);
1349 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1350 // is a list of text input sections sorted in ascending order of their
1351 // output addresses.
1353 fix_exidx_coverage(Layout* layout,
1354 const Text_section_list& sorted_text_section,
1355 Symbol_table* symtab,
1356 bool merge_exidx_entries);
1358 // Link an EXIDX section into its corresponding text section.
1360 set_exidx_section_link();
1364 typedef Output_section::Input_section Input_section;
1365 typedef Output_section::Input_section_list Input_section_list;
1367 // Create a stub group.
1368 void create_stub_group(Input_section_list::const_iterator,
1369 Input_section_list::const_iterator,
1370 Input_section_list::const_iterator,
1371 Target_arm<big_endian>*,
1372 std::vector<Output_relaxed_input_section*>*);
1375 // Arm_exidx_input_section class. This represents an EXIDX input section.
1377 class Arm_exidx_input_section
1380 static const section_offset_type invalid_offset =
1381 static_cast<section_offset_type>(-1);
1383 Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
1384 unsigned int link, uint32_t size, uint32_t addralign)
1385 : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
1386 addralign_(addralign), has_errors_(false)
1389 ~Arm_exidx_input_section()
1392 // Accessors: This is a read-only class.
1394 // Return the object containing this EXIDX input section.
1397 { return this->relobj_; }
1399 // Return the section index of this EXIDX input section.
1402 { return this->shndx_; }
1404 // Return the section index of linked text section in the same object.
1407 { return this->link_; }
1409 // Return size of the EXIDX input section.
1412 { return this->size_; }
1414 // Reutnr address alignment of EXIDX input section.
1417 { return this->addralign_; }
1419 // Whether there are any errors in the EXIDX input section.
1422 { return this->has_errors_; }
1424 // Set has-errors flag.
1427 { this->has_errors_ = true; }
1430 // Object containing this.
1432 // Section index of this.
1433 unsigned int shndx_;
1434 // text section linked to this in the same object.
1436 // Size of this. For ARM 32-bit is sufficient.
1438 // Address alignment of this. For ARM 32-bit is sufficient.
1439 uint32_t addralign_;
1440 // Whether this has any errors.
1444 // Arm_relobj class.
1446 template<bool big_endian>
1447 class Arm_relobj : public Sized_relobj<32, big_endian>
1450 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
1452 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
1453 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
1454 : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
1455 stub_tables_(), local_symbol_is_thumb_function_(),
1456 attributes_section_data_(NULL), mapping_symbols_info_(),
1457 section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
1458 output_local_symbol_count_needs_update_(false),
1459 merge_flags_and_attributes_(true)
1463 { delete this->attributes_section_data_; }
1465 // Return the stub table of the SHNDX-th section if there is one.
1466 Stub_table<big_endian>*
1467 stub_table(unsigned int shndx) const
1469 gold_assert(shndx < this->stub_tables_.size());
1470 return this->stub_tables_[shndx];
1473 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1475 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
1477 gold_assert(shndx < this->stub_tables_.size());
1478 this->stub_tables_[shndx] = stub_table;
1481 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1482 // index. This is only valid after do_count_local_symbol is called.
1484 local_symbol_is_thumb_function(unsigned int r_sym) const
1486 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
1487 return this->local_symbol_is_thumb_function_[r_sym];
1490 // Scan all relocation sections for stub generation.
1492 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
1495 // Convert regular input section with index SHNDX to a relaxed section.
1497 convert_input_section_to_relaxed_section(unsigned shndx)
1499 // The stubs have relocations and we need to process them after writing
1500 // out the stubs. So relocation now must follow section write.
1501 this->set_section_offset(shndx, -1ULL);
1502 this->set_relocs_must_follow_section_writes();
1505 // Downcast a base pointer to an Arm_relobj pointer. This is
1506 // not type-safe but we only use Arm_relobj not the base class.
1507 static Arm_relobj<big_endian>*
1508 as_arm_relobj(Relobj* relobj)
1509 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
1511 // Processor-specific flags in ELF file header. This is valid only after
1514 processor_specific_flags() const
1515 { return this->processor_specific_flags_; }
1517 // Attribute section data This is the contents of the .ARM.attribute section
1519 const Attributes_section_data*
1520 attributes_section_data() const
1521 { return this->attributes_section_data_; }
1523 // Mapping symbol location.
1524 typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
1526 // Functor for STL container.
1527 struct Mapping_symbol_position_less
1530 operator()(const Mapping_symbol_position& p1,
1531 const Mapping_symbol_position& p2) const
1533 return (p1.first < p2.first
1534 || (p1.first == p2.first && p1.second < p2.second));
1538 // We only care about the first character of a mapping symbol, so
1539 // we only store that instead of the whole symbol name.
1540 typedef std::map<Mapping_symbol_position, char,
1541 Mapping_symbol_position_less> Mapping_symbols_info;
1543 // Whether a section contains any Cortex-A8 workaround.
1545 section_has_cortex_a8_workaround(unsigned int shndx) const
1547 return (this->section_has_cortex_a8_workaround_ != NULL
1548 && (*this->section_has_cortex_a8_workaround_)[shndx]);
1551 // Mark a section that has Cortex-A8 workaround.
1553 mark_section_for_cortex_a8_workaround(unsigned int shndx)
1555 if (this->section_has_cortex_a8_workaround_ == NULL)
1556 this->section_has_cortex_a8_workaround_ =
1557 new std::vector<bool>(this->shnum(), false);
1558 (*this->section_has_cortex_a8_workaround_)[shndx] = true;
1561 // Return the EXIDX section of an text section with index SHNDX or NULL
1562 // if the text section has no associated EXIDX section.
1563 const Arm_exidx_input_section*
1564 exidx_input_section_by_link(unsigned int shndx) const
1566 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1567 return ((p != this->exidx_section_map_.end()
1568 && p->second->link() == shndx)
1573 // Return the EXIDX section with index SHNDX or NULL if there is none.
1574 const Arm_exidx_input_section*
1575 exidx_input_section_by_shndx(unsigned shndx) const
1577 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1578 return ((p != this->exidx_section_map_.end()
1579 && p->second->shndx() == shndx)
1584 // Whether output local symbol count needs updating.
1586 output_local_symbol_count_needs_update() const
1587 { return this->output_local_symbol_count_needs_update_; }
1589 // Set output_local_symbol_count_needs_update flag to be true.
1591 set_output_local_symbol_count_needs_update()
1592 { this->output_local_symbol_count_needs_update_ = true; }
1594 // Update output local symbol count at the end of relaxation.
1596 update_output_local_symbol_count();
1598 // Whether we want to merge processor-specific flags and attributes.
1600 merge_flags_and_attributes() const
1601 { return this->merge_flags_and_attributes_; }
1603 // Export list of EXIDX section indices.
1605 get_exidx_shndx_list(std::vector<unsigned int>* list) const
1608 for (Exidx_section_map::const_iterator p = this->exidx_section_map_.begin();
1609 p != this->exidx_section_map_.end();
1612 if (p->second->shndx() == p->first)
1613 list->push_back(p->first);
1615 // Sort list to make result independent of implementation of map.
1616 std::sort(list->begin(), list->end());
1620 // Post constructor setup.
1624 // Call parent's setup method.
1625 Sized_relobj<32, big_endian>::do_setup();
1627 // Initialize look-up tables.
1628 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
1629 this->stub_tables_.swap(empty_stub_table_list);
1632 // Count the local symbols.
1634 do_count_local_symbols(Stringpool_template<char>*,
1635 Stringpool_template<char>*);
1638 do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
1639 const unsigned char* pshdrs,
1640 typename Sized_relobj<32, big_endian>::Views* pivews);
1642 // Read the symbol information.
1644 do_read_symbols(Read_symbols_data* sd);
1646 // Process relocs for garbage collection.
1648 do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
1652 // Whether a section needs to be scanned for relocation stubs.
1654 section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1655 const Relobj::Output_sections&,
1656 const Symbol_table *, const unsigned char*);
1658 // Whether a section is a scannable text section.
1660 section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
1661 const Output_section*, const Symbol_table *);
1663 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1665 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1666 unsigned int, Output_section*,
1667 const Symbol_table *);
1669 // Scan a section for the Cortex-A8 erratum.
1671 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
1672 unsigned int, Output_section*,
1673 Target_arm<big_endian>*);
1675 // Find the linked text section of an EXIDX section by looking at the
1676 // first reloction of the EXIDX section. PSHDR points to the section
1677 // headers of a relocation section and PSYMS points to the local symbols.
1678 // PSHNDX points to a location storing the text section index if found.
1679 // Return whether we can find the linked section.
1681 find_linked_text_section(const unsigned char* pshdr,
1682 const unsigned char* psyms, unsigned int* pshndx);
1685 // Make a new Arm_exidx_input_section object for EXIDX section with
1686 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1687 // index of the linked text section.
1689 make_exidx_input_section(unsigned int shndx,
1690 const elfcpp::Shdr<32, big_endian>& shdr,
1691 unsigned int text_shndx,
1692 const elfcpp::Shdr<32, big_endian>& text_shdr);
1694 // Return the output address of either a plain input section or a
1695 // relaxed input section. SHNDX is the section index.
1697 simple_input_section_output_address(unsigned int, Output_section*);
1699 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
1700 typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
1703 // List of stub tables.
1704 Stub_table_list stub_tables_;
1705 // Bit vector to tell if a local symbol is a thumb function or not.
1706 // This is only valid after do_count_local_symbol is called.
1707 std::vector<bool> local_symbol_is_thumb_function_;
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_;
1712 // Mapping symbols information.
1713 Mapping_symbols_info mapping_symbols_info_;
1714 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1715 std::vector<bool>* section_has_cortex_a8_workaround_;
1716 // Map a text section to its associated .ARM.exidx section, if there is one.
1717 Exidx_section_map exidx_section_map_;
1718 // Whether output local symbol count needs updating.
1719 bool output_local_symbol_count_needs_update_;
1720 // Whether we merge processor flags and attributes of this object to
1722 bool merge_flags_and_attributes_;
1725 // Arm_dynobj class.
1727 template<bool big_endian>
1728 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1731 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1732 const elfcpp::Ehdr<32, big_endian>& ehdr)
1733 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1734 processor_specific_flags_(0), attributes_section_data_(NULL)
1738 { delete this->attributes_section_data_; }
1740 // Downcast a base pointer to an Arm_relobj pointer. This is
1741 // not type-safe but we only use Arm_relobj not the base class.
1742 static Arm_dynobj<big_endian>*
1743 as_arm_dynobj(Dynobj* dynobj)
1744 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1746 // Processor-specific flags in ELF file header. This is valid only after
1749 processor_specific_flags() const
1750 { return this->processor_specific_flags_; }
1752 // Attributes section data.
1753 const Attributes_section_data*
1754 attributes_section_data() const
1755 { return this->attributes_section_data_; }
1758 // Read the symbol information.
1760 do_read_symbols(Read_symbols_data* sd);
1763 // processor-specific flags in ELF file header.
1764 elfcpp::Elf_Word processor_specific_flags_;
1765 // Object attributes if there is an .ARM.attributes section or NULL.
1766 Attributes_section_data* attributes_section_data_;
1769 // Functor to read reloc addends during stub generation.
1771 template<int sh_type, bool big_endian>
1772 struct Stub_addend_reader
1774 // Return the addend for a relocation of a particular type. Depending
1775 // on whether this is a REL or RELA relocation, read the addend from a
1776 // view or from a Reloc object.
1777 elfcpp::Elf_types<32>::Elf_Swxword
1779 unsigned int /* r_type */,
1780 const unsigned char* /* view */,
1781 const typename Reloc_types<sh_type,
1782 32, big_endian>::Reloc& /* reloc */) const;
1785 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1787 template<bool big_endian>
1788 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1790 elfcpp::Elf_types<32>::Elf_Swxword
1793 const unsigned char*,
1794 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1797 // Specialized Stub_addend_reader for RELA type relocation sections.
1798 // We currently do not handle RELA type relocation sections but it is trivial
1799 // to implement the addend reader. This is provided for completeness and to
1800 // make it easier to add support for RELA relocation sections in the future.
1802 template<bool big_endian>
1803 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1805 elfcpp::Elf_types<32>::Elf_Swxword
1808 const unsigned char*,
1809 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1810 big_endian>::Reloc& reloc) const
1811 { return reloc.get_r_addend(); }
1814 // Cortex_a8_reloc class. We keep record of relocation that may need
1815 // the Cortex-A8 erratum workaround.
1817 class Cortex_a8_reloc
1820 Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
1821 Arm_address destination)
1822 : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
1828 // Accessors: This is a read-only class.
1830 // Return the relocation stub associated with this relocation if there is
1834 { return this->reloc_stub_; }
1836 // Return the relocation type.
1839 { return this->r_type_; }
1841 // Return the destination address of the relocation. LSB stores the THUMB
1845 { return this->destination_; }
1848 // Associated relocation stub if there is one, or NULL.
1849 const Reloc_stub* reloc_stub_;
1851 unsigned int r_type_;
1852 // Destination address of this relocation. LSB is used to distinguish
1854 Arm_address destination_;
1857 // Arm_output_data_got class. We derive this from Output_data_got to add
1858 // extra methods to handle TLS relocations in a static link.
1860 template<bool big_endian>
1861 class Arm_output_data_got : public Output_data_got<32, big_endian>
1864 Arm_output_data_got(Symbol_table* symtab, Layout* layout)
1865 : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
1868 // Add a static entry for the GOT entry at OFFSET. GSYM is a global
1869 // symbol and R_TYPE is the code of a dynamic relocation that needs to be
1870 // applied in a static link.
1872 add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1873 { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
1875 // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
1876 // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
1877 // relocation that needs to be applied in a static link.
1879 add_static_reloc(unsigned int got_offset, unsigned int r_type,
1880 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1882 this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
1886 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
1887 // The first one is initialized to be 1, which is the module index for
1888 // the main executable and the second one 0. A reloc of the type
1889 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
1890 // be applied by gold. GSYM is a global symbol.
1892 add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
1894 // Same as the above but for a local symbol in OBJECT with INDEX.
1896 add_tls_gd32_with_static_reloc(unsigned int got_type,
1897 Sized_relobj<32, big_endian>* object,
1898 unsigned int index);
1901 // Write out the GOT table.
1903 do_write(Output_file*);
1906 // This class represent dynamic relocations that need to be applied by
1907 // gold because we are using TLS relocations in a static link.
1911 Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1912 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
1913 { this->u_.global.symbol = gsym; }
1915 Static_reloc(unsigned int got_offset, unsigned int r_type,
1916 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1917 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
1919 this->u_.local.relobj = relobj;
1920 this->u_.local.index = index;
1923 // Return the GOT offset.
1926 { return this->got_offset_; }
1931 { return this->r_type_; }
1933 // Whether the symbol is global or not.
1935 symbol_is_global() const
1936 { return this->symbol_is_global_; }
1938 // For a relocation against a global symbol, the global symbol.
1942 gold_assert(this->symbol_is_global_);
1943 return this->u_.global.symbol;
1946 // For a relocation against a local symbol, the defining object.
1947 Sized_relobj<32, big_endian>*
1950 gold_assert(!this->symbol_is_global_);
1951 return this->u_.local.relobj;
1954 // For a relocation against a local symbol, the local symbol index.
1958 gold_assert(!this->symbol_is_global_);
1959 return this->u_.local.index;
1963 // GOT offset of the entry to which this relocation is applied.
1964 unsigned int got_offset_;
1965 // Type of relocation.
1966 unsigned int r_type_;
1967 // Whether this relocation is against a global symbol.
1968 bool symbol_is_global_;
1969 // A global or local symbol.
1974 // For a global symbol, the symbol itself.
1979 // For a local symbol, the object defining object.
1980 Sized_relobj<32, big_endian>* relobj;
1981 // For a local symbol, the symbol index.
1987 // Symbol table of the output object.
1988 Symbol_table* symbol_table_;
1989 // Layout of the output object.
1991 // Static relocs to be applied to the GOT.
1992 std::vector<Static_reloc> static_relocs_;
1995 // The ARM target has many relocation types with odd-sizes or incontigious
1996 // bits. The default handling of relocatable relocation cannot process these
1997 // relocations. So we have to extend the default code.
1999 template<bool big_endian, int sh_type, typename Classify_reloc>
2000 class Arm_scan_relocatable_relocs :
2001 public Default_scan_relocatable_relocs<sh_type, Classify_reloc>
2004 // Return the strategy to use for a local symbol which is a section
2005 // symbol, given the relocation type.
2006 inline Relocatable_relocs::Reloc_strategy
2007 local_section_strategy(unsigned int r_type, Relobj*)
2009 if (sh_type == elfcpp::SHT_RELA)
2010 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
2013 if (r_type == elfcpp::R_ARM_TARGET1
2014 || r_type == elfcpp::R_ARM_TARGET2)
2016 const Target_arm<big_endian>* arm_target =
2017 Target_arm<big_endian>::default_target();
2018 r_type = arm_target->get_real_reloc_type(r_type);
2023 // Relocations that write nothing. These exclude R_ARM_TARGET1
2024 // and R_ARM_TARGET2.
2025 case elfcpp::R_ARM_NONE:
2026 case elfcpp::R_ARM_V4BX:
2027 case elfcpp::R_ARM_TLS_GOTDESC:
2028 case elfcpp::R_ARM_TLS_CALL:
2029 case elfcpp::R_ARM_TLS_DESCSEQ:
2030 case elfcpp::R_ARM_THM_TLS_CALL:
2031 case elfcpp::R_ARM_GOTRELAX:
2032 case elfcpp::R_ARM_GNU_VTENTRY:
2033 case elfcpp::R_ARM_GNU_VTINHERIT:
2034 case elfcpp::R_ARM_THM_TLS_DESCSEQ16:
2035 case elfcpp::R_ARM_THM_TLS_DESCSEQ32:
2036 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
2037 // These should have been converted to something else above.
2038 case elfcpp::R_ARM_TARGET1:
2039 case elfcpp::R_ARM_TARGET2:
2041 // Relocations that write full 32 bits.
2042 case elfcpp::R_ARM_ABS32:
2043 case elfcpp::R_ARM_REL32:
2044 case elfcpp::R_ARM_SBREL32:
2045 case elfcpp::R_ARM_GOTOFF32:
2046 case elfcpp::R_ARM_BASE_PREL:
2047 case elfcpp::R_ARM_GOT_BREL:
2048 case elfcpp::R_ARM_BASE_ABS:
2049 case elfcpp::R_ARM_ABS32_NOI:
2050 case elfcpp::R_ARM_REL32_NOI:
2051 case elfcpp::R_ARM_PLT32_ABS:
2052 case elfcpp::R_ARM_GOT_ABS:
2053 case elfcpp::R_ARM_GOT_PREL:
2054 case elfcpp::R_ARM_TLS_GD32:
2055 case elfcpp::R_ARM_TLS_LDM32:
2056 case elfcpp::R_ARM_TLS_LDO32:
2057 case elfcpp::R_ARM_TLS_IE32:
2058 case elfcpp::R_ARM_TLS_LE32:
2059 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
2061 // For all other static relocations, return RELOC_SPECIAL.
2062 return Relocatable_relocs::RELOC_SPECIAL;
2068 // Utilities for manipulating integers of up to 32-bits
2072 // Sign extend an n-bit unsigned integer stored in an uint32_t into
2073 // an int32_t. NO_BITS must be between 1 to 32.
2074 template<int no_bits>
2075 static inline int32_t
2076 sign_extend(uint32_t bits)
2078 gold_assert(no_bits >= 0 && no_bits <= 32);
2080 return static_cast<int32_t>(bits);
2081 uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
2083 uint32_t top_bit = 1U << (no_bits - 1);
2084 int32_t as_signed = static_cast<int32_t>(bits);
2085 return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
2088 // Detects overflow of an NO_BITS integer stored in a uint32_t.
2089 template<int no_bits>
2091 has_overflow(uint32_t bits)
2093 gold_assert(no_bits >= 0 && no_bits <= 32);
2096 int32_t max = (1 << (no_bits - 1)) - 1;
2097 int32_t min = -(1 << (no_bits - 1));
2098 int32_t as_signed = static_cast<int32_t>(bits);
2099 return as_signed > max || as_signed < min;
2102 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
2103 // fits in the given number of bits as either a signed or unsigned value.
2104 // For example, has_signed_unsigned_overflow<8> would check
2105 // -128 <= bits <= 255
2106 template<int no_bits>
2108 has_signed_unsigned_overflow(uint32_t bits)
2110 gold_assert(no_bits >= 2 && no_bits <= 32);
2113 int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
2114 int32_t min = -(1 << (no_bits - 1));
2115 int32_t as_signed = static_cast<int32_t>(bits);
2116 return as_signed > max || as_signed < min;
2119 // Select bits from A and B using bits in MASK. For each n in [0..31],
2120 // the n-th bit in the result is chosen from the n-th bits of A and B.
2121 // A zero selects A and a one selects B.
2122 static inline uint32_t
2123 bit_select(uint32_t a, uint32_t b, uint32_t mask)
2124 { return (a & ~mask) | (b & mask); }
2127 template<bool big_endian>
2128 class Target_arm : public Sized_target<32, big_endian>
2131 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
2134 // When were are relocating a stub, we pass this as the relocation number.
2135 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
2138 : Sized_target<32, big_endian>(&arm_info),
2139 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
2140 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
2141 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
2142 stub_tables_(), stub_factory_(Stub_factory::get_instance()),
2143 may_use_blx_(false), should_force_pic_veneer_(false),
2144 arm_input_section_map_(), attributes_section_data_(NULL),
2145 fix_cortex_a8_(false), cortex_a8_relocs_info_()
2148 // Virtual function which is set to return true by a target if
2149 // it can use relocation types to determine if a function's
2150 // pointer is taken.
2152 can_check_for_function_pointers() const
2155 // Whether a section called SECTION_NAME may have function pointers to
2156 // sections not eligible for safe ICF folding.
2158 section_may_have_icf_unsafe_pointers(const char* section_name) const
2160 return (!is_prefix_of(".ARM.exidx", section_name)
2161 && !is_prefix_of(".ARM.extab", section_name)
2162 && Target::section_may_have_icf_unsafe_pointers(section_name));
2165 // Whether we can use BLX.
2168 { return this->may_use_blx_; }
2170 // Set use-BLX flag.
2172 set_may_use_blx(bool value)
2173 { this->may_use_blx_ = value; }
2175 // Whether we force PCI branch veneers.
2177 should_force_pic_veneer() const
2178 { return this->should_force_pic_veneer_; }
2180 // Set PIC veneer flag.
2182 set_should_force_pic_veneer(bool value)
2183 { this->should_force_pic_veneer_ = value; }
2185 // Whether we use THUMB-2 instructions.
2187 using_thumb2() const
2189 Object_attribute* attr =
2190 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2191 int arch = attr->int_value();
2192 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
2195 // Whether we use THUMB/THUMB-2 instructions only.
2197 using_thumb_only() const
2199 Object_attribute* attr =
2200 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2202 if (attr->int_value() == elfcpp::TAG_CPU_ARCH_V6_M
2203 || attr->int_value() == elfcpp::TAG_CPU_ARCH_V6S_M)
2205 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2206 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2208 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2209 return attr->int_value() == 'M';
2212 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2214 may_use_arm_nop() const
2216 Object_attribute* attr =
2217 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2218 int arch = attr->int_value();
2219 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2220 || arch == elfcpp::TAG_CPU_ARCH_V6K
2221 || arch == elfcpp::TAG_CPU_ARCH_V7
2222 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2225 // Whether we have THUMB-2 NOP.W instruction.
2227 may_use_thumb2_nop() const
2229 Object_attribute* attr =
2230 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2231 int arch = attr->int_value();
2232 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2233 || arch == elfcpp::TAG_CPU_ARCH_V7
2234 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2237 // Process the relocations to determine unreferenced sections for
2238 // garbage collection.
2240 gc_process_relocs(Symbol_table* symtab,
2242 Sized_relobj<32, big_endian>* object,
2243 unsigned int data_shndx,
2244 unsigned int sh_type,
2245 const unsigned char* prelocs,
2247 Output_section* output_section,
2248 bool needs_special_offset_handling,
2249 size_t local_symbol_count,
2250 const unsigned char* plocal_symbols);
2252 // Scan the relocations to look for symbol adjustments.
2254 scan_relocs(Symbol_table* symtab,
2256 Sized_relobj<32, big_endian>* object,
2257 unsigned int data_shndx,
2258 unsigned int sh_type,
2259 const unsigned char* prelocs,
2261 Output_section* output_section,
2262 bool needs_special_offset_handling,
2263 size_t local_symbol_count,
2264 const unsigned char* plocal_symbols);
2266 // Finalize the sections.
2268 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2270 // Return the value to use for a dynamic symbol which requires special
2273 do_dynsym_value(const Symbol*) const;
2275 // Relocate a section.
2277 relocate_section(const Relocate_info<32, big_endian>*,
2278 unsigned int sh_type,
2279 const unsigned char* prelocs,
2281 Output_section* output_section,
2282 bool needs_special_offset_handling,
2283 unsigned char* view,
2284 Arm_address view_address,
2285 section_size_type view_size,
2286 const Reloc_symbol_changes*);
2288 // Scan the relocs during a relocatable link.
2290 scan_relocatable_relocs(Symbol_table* symtab,
2292 Sized_relobj<32, big_endian>* object,
2293 unsigned int data_shndx,
2294 unsigned int sh_type,
2295 const unsigned char* prelocs,
2297 Output_section* output_section,
2298 bool needs_special_offset_handling,
2299 size_t local_symbol_count,
2300 const unsigned char* plocal_symbols,
2301 Relocatable_relocs*);
2303 // Relocate a section during a relocatable link.
2305 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
2306 unsigned int sh_type,
2307 const unsigned char* prelocs,
2309 Output_section* output_section,
2310 off_t offset_in_output_section,
2311 const Relocatable_relocs*,
2312 unsigned char* view,
2313 Arm_address view_address,
2314 section_size_type view_size,
2315 unsigned char* reloc_view,
2316 section_size_type reloc_view_size);
2318 // Perform target-specific processing in a relocatable link. This is
2319 // only used if we use the relocation strategy RELOC_SPECIAL.
2321 relocate_special_relocatable(const Relocate_info<32, big_endian>* relinfo,
2322 unsigned int sh_type,
2323 const unsigned char* preloc_in,
2325 Output_section* output_section,
2326 off_t offset_in_output_section,
2327 unsigned char* view,
2328 typename elfcpp::Elf_types<32>::Elf_Addr
2330 section_size_type view_size,
2331 unsigned char* preloc_out);
2333 // Return whether SYM is defined by the ABI.
2335 do_is_defined_by_abi(Symbol* sym) const
2336 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2338 // Return whether there is a GOT section.
2340 has_got_section() const
2341 { return this->got_ != NULL; }
2343 // Return the size of the GOT section.
2347 gold_assert(this->got_ != NULL);
2348 return this->got_->data_size();
2351 // Map platform-specific reloc types
2353 get_real_reloc_type (unsigned int r_type);
2356 // Methods to support stub-generations.
2359 // Return the stub factory
2361 stub_factory() const
2362 { return this->stub_factory_; }
2364 // Make a new Arm_input_section object.
2365 Arm_input_section<big_endian>*
2366 new_arm_input_section(Relobj*, unsigned int);
2368 // Find the Arm_input_section object corresponding to the SHNDX-th input
2369 // section of RELOBJ.
2370 Arm_input_section<big_endian>*
2371 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2373 // Make a new Stub_table
2374 Stub_table<big_endian>*
2375 new_stub_table(Arm_input_section<big_endian>*);
2377 // Scan a section for stub generation.
2379 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2380 const unsigned char*, size_t, Output_section*,
2381 bool, const unsigned char*, Arm_address,
2386 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2387 Output_section*, unsigned char*, Arm_address,
2390 // Get the default ARM target.
2391 static Target_arm<big_endian>*
2394 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2395 && parameters->target().is_big_endian() == big_endian);
2396 return static_cast<Target_arm<big_endian>*>(
2397 parameters->sized_target<32, big_endian>());
2400 // Whether NAME belongs to a mapping symbol.
2402 is_mapping_symbol_name(const char* name)
2406 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2407 && (name[2] == '\0' || name[2] == '.'));
2410 // Whether we work around the Cortex-A8 erratum.
2412 fix_cortex_a8() const
2413 { return this->fix_cortex_a8_; }
2415 // Whether we merge exidx entries in debuginfo.
2417 merge_exidx_entries() const
2418 { return parameters->options().merge_exidx_entries(); }
2420 // Whether we fix R_ARM_V4BX relocation.
2422 // 1 - replace with MOV instruction (armv4 target)
2423 // 2 - make interworking veneer (>= armv4t targets only)
2424 General_options::Fix_v4bx
2426 { return parameters->options().fix_v4bx(); }
2428 // Scan a span of THUMB code section for Cortex-A8 erratum.
2430 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2431 section_size_type, section_size_type,
2432 const unsigned char*, Arm_address);
2434 // Apply Cortex-A8 workaround to a branch.
2436 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2437 unsigned char*, Arm_address);
2440 // Make an ELF object.
2442 do_make_elf_object(const std::string&, Input_file*, off_t,
2443 const elfcpp::Ehdr<32, big_endian>& ehdr);
2446 do_make_elf_object(const std::string&, Input_file*, off_t,
2447 const elfcpp::Ehdr<32, !big_endian>&)
2448 { gold_unreachable(); }
2451 do_make_elf_object(const std::string&, Input_file*, off_t,
2452 const elfcpp::Ehdr<64, false>&)
2453 { gold_unreachable(); }
2456 do_make_elf_object(const std::string&, Input_file*, off_t,
2457 const elfcpp::Ehdr<64, true>&)
2458 { gold_unreachable(); }
2460 // Make an output section.
2462 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2463 elfcpp::Elf_Xword flags)
2464 { return new Arm_output_section<big_endian>(name, type, flags); }
2467 do_adjust_elf_header(unsigned char* view, int len) const;
2469 // We only need to generate stubs, and hence perform relaxation if we are
2470 // not doing relocatable linking.
2472 do_may_relax() const
2473 { return !parameters->options().relocatable(); }
2476 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
2478 // Determine whether an object attribute tag takes an integer, a
2481 do_attribute_arg_type(int tag) const;
2483 // Reorder tags during output.
2485 do_attributes_order(int num) const;
2487 // This is called when the target is selected as the default.
2489 do_select_as_default_target()
2491 // No locking is required since there should only be one default target.
2492 // We cannot have both the big-endian and little-endian ARM targets
2494 gold_assert(arm_reloc_property_table == NULL);
2495 arm_reloc_property_table = new Arm_reloc_property_table();
2499 // The class which scans relocations.
2504 : issued_non_pic_error_(false)
2508 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2509 Sized_relobj<32, big_endian>* object,
2510 unsigned int data_shndx,
2511 Output_section* output_section,
2512 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2513 const elfcpp::Sym<32, big_endian>& lsym);
2516 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2517 Sized_relobj<32, big_endian>* object,
2518 unsigned int data_shndx,
2519 Output_section* output_section,
2520 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2524 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2525 Sized_relobj<32, big_endian>* ,
2528 const elfcpp::Rel<32, big_endian>& ,
2530 const elfcpp::Sym<32, big_endian>&);
2533 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2534 Sized_relobj<32, big_endian>* ,
2537 const elfcpp::Rel<32, big_endian>& ,
2538 unsigned int , Symbol*);
2542 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
2543 unsigned int r_type);
2546 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
2547 unsigned int r_type, Symbol*);
2550 check_non_pic(Relobj*, unsigned int r_type);
2552 // Almost identical to Symbol::needs_plt_entry except that it also
2553 // handles STT_ARM_TFUNC.
2555 symbol_needs_plt_entry(const Symbol* sym)
2557 // An undefined symbol from an executable does not need a PLT entry.
2558 if (sym->is_undefined() && !parameters->options().shared())
2561 return (!parameters->doing_static_link()
2562 && (sym->type() == elfcpp::STT_FUNC
2563 || sym->type() == elfcpp::STT_ARM_TFUNC)
2564 && (sym->is_from_dynobj()
2565 || sym->is_undefined()
2566 || sym->is_preemptible()));
2570 possible_function_pointer_reloc(unsigned int r_type);
2572 // Whether we have issued an error about a non-PIC compilation.
2573 bool issued_non_pic_error_;
2576 // The class which implements relocation.
2586 // Return whether the static relocation needs to be applied.
2588 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2591 Output_section* output_section);
2593 // Do a relocation. Return false if the caller should not issue
2594 // any warnings about this relocation.
2596 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2597 Output_section*, size_t relnum,
2598 const elfcpp::Rel<32, big_endian>&,
2599 unsigned int r_type, const Sized_symbol<32>*,
2600 const Symbol_value<32>*,
2601 unsigned char*, Arm_address,
2604 // Return whether we want to pass flag NON_PIC_REF for this
2605 // reloc. This means the relocation type accesses a symbol not via
2608 reloc_is_non_pic (unsigned int r_type)
2612 // These relocation types reference GOT or PLT entries explicitly.
2613 case elfcpp::R_ARM_GOT_BREL:
2614 case elfcpp::R_ARM_GOT_ABS:
2615 case elfcpp::R_ARM_GOT_PREL:
2616 case elfcpp::R_ARM_GOT_BREL12:
2617 case elfcpp::R_ARM_PLT32_ABS:
2618 case elfcpp::R_ARM_TLS_GD32:
2619 case elfcpp::R_ARM_TLS_LDM32:
2620 case elfcpp::R_ARM_TLS_IE32:
2621 case elfcpp::R_ARM_TLS_IE12GP:
2623 // These relocate types may use PLT entries.
2624 case elfcpp::R_ARM_CALL:
2625 case elfcpp::R_ARM_THM_CALL:
2626 case elfcpp::R_ARM_JUMP24:
2627 case elfcpp::R_ARM_THM_JUMP24:
2628 case elfcpp::R_ARM_THM_JUMP19:
2629 case elfcpp::R_ARM_PLT32:
2630 case elfcpp::R_ARM_THM_XPC22:
2631 case elfcpp::R_ARM_PREL31:
2632 case elfcpp::R_ARM_SBREL31:
2641 // Do a TLS relocation.
2642 inline typename Arm_relocate_functions<big_endian>::Status
2643 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2644 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2645 const Sized_symbol<32>*, const Symbol_value<32>*,
2646 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2651 // A class which returns the size required for a relocation type,
2652 // used while scanning relocs during a relocatable link.
2653 class Relocatable_size_for_reloc
2657 get_size_for_reloc(unsigned int, Relobj*);
2660 // Adjust TLS relocation type based on the options and whether this
2661 // is a local symbol.
2662 static tls::Tls_optimization
2663 optimize_tls_reloc(bool is_final, int r_type);
2665 // Get the GOT section, creating it if necessary.
2666 Arm_output_data_got<big_endian>*
2667 got_section(Symbol_table*, Layout*);
2669 // Get the GOT PLT section.
2671 got_plt_section() const
2673 gold_assert(this->got_plt_ != NULL);
2674 return this->got_plt_;
2677 // Create a PLT entry for a global symbol.
2679 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2681 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2683 define_tls_base_symbol(Symbol_table*, Layout*);
2685 // Create a GOT entry for the TLS module index.
2687 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2688 Sized_relobj<32, big_endian>* object);
2690 // Get the PLT section.
2691 const Output_data_plt_arm<big_endian>*
2694 gold_assert(this->plt_ != NULL);
2698 // Get the dynamic reloc section, creating it if necessary.
2700 rel_dyn_section(Layout*);
2702 // Get the section to use for TLS_DESC relocations.
2704 rel_tls_desc_section(Layout*) const;
2706 // Return true if the symbol may need a COPY relocation.
2707 // References from an executable object to non-function symbols
2708 // defined in a dynamic object may need a COPY relocation.
2710 may_need_copy_reloc(Symbol* gsym)
2712 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2713 && gsym->may_need_copy_reloc());
2716 // Add a potential copy relocation.
2718 copy_reloc(Symbol_table* symtab, Layout* layout,
2719 Sized_relobj<32, big_endian>* object,
2720 unsigned int shndx, Output_section* output_section,
2721 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2723 this->copy_relocs_.copy_reloc(symtab, layout,
2724 symtab->get_sized_symbol<32>(sym),
2725 object, shndx, output_section, reloc,
2726 this->rel_dyn_section(layout));
2729 // Whether two EABI versions are compatible.
2731 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2733 // Merge processor-specific flags from input object and those in the ELF
2734 // header of the output.
2736 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2738 // Get the secondary compatible architecture.
2740 get_secondary_compatible_arch(const Attributes_section_data*);
2742 // Set the secondary compatible architecture.
2744 set_secondary_compatible_arch(Attributes_section_data*, int);
2747 tag_cpu_arch_combine(const char*, int, int*, int, int);
2749 // Helper to print AEABI enum tag value.
2751 aeabi_enum_name(unsigned int);
2753 // Return string value for TAG_CPU_name.
2755 tag_cpu_name_value(unsigned int);
2757 // Merge object attributes from input object and those in the output.
2759 merge_object_attributes(const char*, const Attributes_section_data*);
2761 // Helper to get an AEABI object attribute
2763 get_aeabi_object_attribute(int tag) const
2765 Attributes_section_data* pasd = this->attributes_section_data_;
2766 gold_assert(pasd != NULL);
2767 Object_attribute* attr =
2768 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2769 gold_assert(attr != NULL);
2774 // Methods to support stub-generations.
2777 // Group input sections for stub generation.
2779 group_sections(Layout*, section_size_type, bool);
2781 // Scan a relocation for stub generation.
2783 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2784 const Sized_symbol<32>*, unsigned int,
2785 const Symbol_value<32>*,
2786 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2788 // Scan a relocation section for stub.
2789 template<int sh_type>
2791 scan_reloc_section_for_stubs(
2792 const Relocate_info<32, big_endian>* relinfo,
2793 const unsigned char* prelocs,
2795 Output_section* output_section,
2796 bool needs_special_offset_handling,
2797 const unsigned char* view,
2798 elfcpp::Elf_types<32>::Elf_Addr view_address,
2801 // Fix .ARM.exidx section coverage.
2803 fix_exidx_coverage(Layout*, const Input_objects*,
2804 Arm_output_section<big_endian>*, Symbol_table*);
2806 // Functors for STL set.
2807 struct output_section_address_less_than
2810 operator()(const Output_section* s1, const Output_section* s2) const
2811 { return s1->address() < s2->address(); }
2814 // Information about this specific target which we pass to the
2815 // general Target structure.
2816 static const Target::Target_info arm_info;
2818 // The types of GOT entries needed for this platform.
2821 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2822 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2823 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2824 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2825 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2828 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2830 // Map input section to Arm_input_section.
2831 typedef Unordered_map<Section_id,
2832 Arm_input_section<big_endian>*,
2834 Arm_input_section_map;
2836 // Map output addresses to relocs for Cortex-A8 erratum.
2837 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2838 Cortex_a8_relocs_info;
2841 Arm_output_data_got<big_endian>* got_;
2843 Output_data_plt_arm<big_endian>* plt_;
2844 // The GOT PLT section.
2845 Output_data_space* got_plt_;
2846 // The dynamic reloc section.
2847 Reloc_section* rel_dyn_;
2848 // Relocs saved to avoid a COPY reloc.
2849 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2850 // Space for variables copied with a COPY reloc.
2851 Output_data_space* dynbss_;
2852 // Offset of the GOT entry for the TLS module index.
2853 unsigned int got_mod_index_offset_;
2854 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2855 bool tls_base_symbol_defined_;
2856 // Vector of Stub_tables created.
2857 Stub_table_list stub_tables_;
2859 const Stub_factory &stub_factory_;
2860 // Whether we can use BLX.
2862 // Whether we force PIC branch veneers.
2863 bool should_force_pic_veneer_;
2864 // Map for locating Arm_input_sections.
2865 Arm_input_section_map arm_input_section_map_;
2866 // Attributes section data in output.
2867 Attributes_section_data* attributes_section_data_;
2868 // Whether we want to fix code for Cortex-A8 erratum.
2869 bool fix_cortex_a8_;
2870 // Map addresses to relocs for Cortex-A8 erratum.
2871 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2874 template<bool big_endian>
2875 const Target::Target_info Target_arm<big_endian>::arm_info =
2878 big_endian, // is_big_endian
2879 elfcpp::EM_ARM, // machine_code
2880 false, // has_make_symbol
2881 false, // has_resolve
2882 false, // has_code_fill
2883 true, // is_default_stack_executable
2885 "/usr/lib/libc.so.1", // dynamic_linker
2886 0x8000, // default_text_segment_address
2887 0x1000, // abi_pagesize (overridable by -z max-page-size)
2888 0x1000, // common_pagesize (overridable by -z common-page-size)
2889 elfcpp::SHN_UNDEF, // small_common_shndx
2890 elfcpp::SHN_UNDEF, // large_common_shndx
2891 0, // small_common_section_flags
2892 0, // large_common_section_flags
2893 ".ARM.attributes", // attributes_section
2894 "aeabi" // attributes_vendor
2897 // Arm relocate functions class
2900 template<bool big_endian>
2901 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2906 STATUS_OKAY, // No error during relocation.
2907 STATUS_OVERFLOW, // Relocation oveflow.
2908 STATUS_BAD_RELOC // Relocation cannot be applied.
2912 typedef Relocate_functions<32, big_endian> Base;
2913 typedef Arm_relocate_functions<big_endian> This;
2915 // Encoding of imm16 argument for movt and movw ARM instructions
2918 // imm16 := imm4 | imm12
2920 // 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
2921 // +-------+---------------+-------+-------+-----------------------+
2922 // | | |imm4 | |imm12 |
2923 // +-------+---------------+-------+-------+-----------------------+
2925 // Extract the relocation addend from VAL based on the ARM
2926 // instruction encoding described above.
2927 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2928 extract_arm_movw_movt_addend(
2929 typename elfcpp::Swap<32, big_endian>::Valtype val)
2931 // According to the Elf ABI for ARM Architecture the immediate
2932 // field is sign-extended to form the addend.
2933 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
2936 // Insert X into VAL based on the ARM instruction encoding described
2938 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2939 insert_val_arm_movw_movt(
2940 typename elfcpp::Swap<32, big_endian>::Valtype val,
2941 typename elfcpp::Swap<32, big_endian>::Valtype x)
2945 val |= (x & 0xf000) << 4;
2949 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2952 // imm16 := imm4 | i | imm3 | imm8
2954 // 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
2955 // +---------+-+-----------+-------++-+-----+-------+---------------+
2956 // | |i| |imm4 || |imm3 | |imm8 |
2957 // +---------+-+-----------+-------++-+-----+-------+---------------+
2959 // Extract the relocation addend from VAL based on the Thumb2
2960 // instruction encoding described above.
2961 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2962 extract_thumb_movw_movt_addend(
2963 typename elfcpp::Swap<32, big_endian>::Valtype val)
2965 // According to the Elf ABI for ARM Architecture the immediate
2966 // field is sign-extended to form the addend.
2967 return utils::sign_extend<16>(((val >> 4) & 0xf000)
2968 | ((val >> 15) & 0x0800)
2969 | ((val >> 4) & 0x0700)
2973 // Insert X into VAL based on the Thumb2 instruction encoding
2975 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2976 insert_val_thumb_movw_movt(
2977 typename elfcpp::Swap<32, big_endian>::Valtype val,
2978 typename elfcpp::Swap<32, big_endian>::Valtype x)
2981 val |= (x & 0xf000) << 4;
2982 val |= (x & 0x0800) << 15;
2983 val |= (x & 0x0700) << 4;
2984 val |= (x & 0x00ff);
2988 // Calculate the smallest constant Kn for the specified residual.
2989 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2991 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
2997 // Determine the most significant bit in the residual and
2998 // align the resulting value to a 2-bit boundary.
2999 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
3001 // The desired shift is now (msb - 6), or zero, whichever
3003 return (((msb - 6) < 0) ? 0 : (msb - 6));
3006 // Calculate the final residual for the specified group index.
3007 // If the passed group index is less than zero, the method will return
3008 // the value of the specified residual without any change.
3009 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3010 static typename elfcpp::Swap<32, big_endian>::Valtype
3011 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3014 for (int n = 0; n <= group; n++)
3016 // Calculate which part of the value to mask.
3017 uint32_t shift = calc_grp_kn(residual);
3018 // Calculate the residual for the next time around.
3019 residual &= ~(residual & (0xff << shift));
3025 // Calculate the value of Gn for the specified group index.
3026 // We return it in the form of an encoded constant-and-rotation.
3027 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3028 static typename elfcpp::Swap<32, big_endian>::Valtype
3029 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3032 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
3035 for (int n = 0; n <= group; n++)
3037 // Calculate which part of the value to mask.
3038 shift = calc_grp_kn(residual);
3039 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
3040 gn = residual & (0xff << shift);
3041 // Calculate the residual for the next time around.
3044 // Return Gn in the form of an encoded constant-and-rotation.
3045 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
3049 // Handle ARM long branches.
3050 static typename This::Status
3051 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3052 unsigned char *, const Sized_symbol<32>*,
3053 const Arm_relobj<big_endian>*, unsigned int,
3054 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3056 // Handle THUMB long branches.
3057 static typename This::Status
3058 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3059 unsigned char *, const Sized_symbol<32>*,
3060 const Arm_relobj<big_endian>*, unsigned int,
3061 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3064 // Return the branch offset of a 32-bit THUMB branch.
3065 static inline int32_t
3066 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3068 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
3069 // involving the J1 and J2 bits.
3070 uint32_t s = (upper_insn & (1U << 10)) >> 10;
3071 uint32_t upper = upper_insn & 0x3ffU;
3072 uint32_t lower = lower_insn & 0x7ffU;
3073 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
3074 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
3075 uint32_t i1 = j1 ^ s ? 0 : 1;
3076 uint32_t i2 = j2 ^ s ? 0 : 1;
3078 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
3079 | (upper << 12) | (lower << 1));
3082 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
3083 // UPPER_INSN is the original upper instruction of the branch. Caller is
3084 // responsible for overflow checking and BLX offset adjustment.
3085 static inline uint16_t
3086 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
3088 uint32_t s = offset < 0 ? 1 : 0;
3089 uint32_t bits = static_cast<uint32_t>(offset);
3090 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
3093 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
3094 // LOWER_INSN is the original lower instruction of the branch. Caller is
3095 // responsible for overflow checking and BLX offset adjustment.
3096 static inline uint16_t
3097 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
3099 uint32_t s = offset < 0 ? 1 : 0;
3100 uint32_t bits = static_cast<uint32_t>(offset);
3101 return ((lower_insn & ~0x2fffU)
3102 | ((((bits >> 23) & 1) ^ !s) << 13)
3103 | ((((bits >> 22) & 1) ^ !s) << 11)
3104 | ((bits >> 1) & 0x7ffU));
3107 // Return the branch offset of a 32-bit THUMB conditional branch.
3108 static inline int32_t
3109 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3111 uint32_t s = (upper_insn & 0x0400U) >> 10;
3112 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
3113 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
3114 uint32_t lower = (lower_insn & 0x07ffU);
3115 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
3117 return utils::sign_extend<21>((upper << 12) | (lower << 1));
3120 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
3121 // instruction. UPPER_INSN is the original upper instruction of the branch.
3122 // Caller is responsible for overflow checking.
3123 static inline uint16_t
3124 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
3126 uint32_t s = offset < 0 ? 1 : 0;
3127 uint32_t bits = static_cast<uint32_t>(offset);
3128 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
3131 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
3132 // instruction. LOWER_INSN is the original lower instruction of the branch.
3133 // Caller is reponsible for overflow checking.
3134 static inline uint16_t
3135 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
3137 uint32_t bits = static_cast<uint32_t>(offset);
3138 uint32_t j2 = (bits & 0x00080000U) >> 19;
3139 uint32_t j1 = (bits & 0x00040000U) >> 18;
3140 uint32_t lo = (bits & 0x00000ffeU) >> 1;
3142 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
3145 // R_ARM_ABS8: S + A
3146 static inline typename This::Status
3147 abs8(unsigned char *view,
3148 const Sized_relobj<32, big_endian>* object,
3149 const Symbol_value<32>* psymval)
3151 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
3152 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3153 Valtype* wv = reinterpret_cast<Valtype*>(view);
3154 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
3155 Reltype addend = utils::sign_extend<8>(val);
3156 Reltype x = psymval->value(object, addend);
3157 val = utils::bit_select(val, x, 0xffU);
3158 elfcpp::Swap<8, big_endian>::writeval(wv, val);
3160 // R_ARM_ABS8 permits signed or unsigned results.
3161 int signed_x = static_cast<int32_t>(x);
3162 return ((signed_x < -128 || signed_x > 255)
3163 ? This::STATUS_OVERFLOW
3164 : This::STATUS_OKAY);
3167 // R_ARM_THM_ABS5: S + A
3168 static inline typename This::Status
3169 thm_abs5(unsigned char *view,
3170 const Sized_relobj<32, big_endian>* object,
3171 const Symbol_value<32>* psymval)
3173 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3174 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3175 Valtype* wv = reinterpret_cast<Valtype*>(view);
3176 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3177 Reltype addend = (val & 0x7e0U) >> 6;
3178 Reltype x = psymval->value(object, addend);
3179 val = utils::bit_select(val, x << 6, 0x7e0U);
3180 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3182 // R_ARM_ABS16 permits signed or unsigned results.
3183 int signed_x = static_cast<int32_t>(x);
3184 return ((signed_x < -32768 || signed_x > 65535)
3185 ? This::STATUS_OVERFLOW
3186 : This::STATUS_OKAY);
3189 // R_ARM_ABS12: S + A
3190 static inline typename This::Status
3191 abs12(unsigned char *view,
3192 const Sized_relobj<32, big_endian>* object,
3193 const Symbol_value<32>* psymval)
3195 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3196 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3197 Valtype* wv = reinterpret_cast<Valtype*>(view);
3198 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3199 Reltype addend = val & 0x0fffU;
3200 Reltype x = psymval->value(object, addend);
3201 val = utils::bit_select(val, x, 0x0fffU);
3202 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3203 return (utils::has_overflow<12>(x)
3204 ? This::STATUS_OVERFLOW
3205 : This::STATUS_OKAY);
3208 // R_ARM_ABS16: S + A
3209 static inline typename This::Status
3210 abs16(unsigned char *view,
3211 const Sized_relobj<32, big_endian>* object,
3212 const Symbol_value<32>* psymval)
3214 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3215 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3216 Valtype* wv = reinterpret_cast<Valtype*>(view);
3217 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3218 Reltype addend = utils::sign_extend<16>(val);
3219 Reltype x = psymval->value(object, addend);
3220 val = utils::bit_select(val, x, 0xffffU);
3221 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3222 return (utils::has_signed_unsigned_overflow<16>(x)
3223 ? This::STATUS_OVERFLOW
3224 : This::STATUS_OKAY);
3227 // R_ARM_ABS32: (S + A) | T
3228 static inline typename This::Status
3229 abs32(unsigned char *view,
3230 const Sized_relobj<32, big_endian>* object,
3231 const Symbol_value<32>* psymval,
3232 Arm_address thumb_bit)
3234 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3235 Valtype* wv = reinterpret_cast<Valtype*>(view);
3236 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3237 Valtype x = psymval->value(object, addend) | thumb_bit;
3238 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3239 return This::STATUS_OKAY;
3242 // R_ARM_REL32: (S + A) | T - P
3243 static inline typename This::Status
3244 rel32(unsigned char *view,
3245 const Sized_relobj<32, big_endian>* object,
3246 const Symbol_value<32>* psymval,
3247 Arm_address address,
3248 Arm_address thumb_bit)
3250 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3251 Valtype* wv = reinterpret_cast<Valtype*>(view);
3252 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3253 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3254 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3255 return This::STATUS_OKAY;
3258 // R_ARM_THM_JUMP24: (S + A) | T - P
3259 static typename This::Status
3260 thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object,
3261 const Symbol_value<32>* psymval, Arm_address address,
3262 Arm_address thumb_bit);
3264 // R_ARM_THM_JUMP6: S + A – P
3265 static inline typename This::Status
3266 thm_jump6(unsigned char *view,
3267 const Sized_relobj<32, big_endian>* object,
3268 const Symbol_value<32>* psymval,
3269 Arm_address address)
3271 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3272 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3273 Valtype* wv = reinterpret_cast<Valtype*>(view);
3274 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3275 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3276 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3277 Reltype x = (psymval->value(object, addend) - address);
3278 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3279 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3280 // CZB does only forward jumps.
3281 return ((x > 0x007e)
3282 ? This::STATUS_OVERFLOW
3283 : This::STATUS_OKAY);
3286 // R_ARM_THM_JUMP8: S + A – P
3287 static inline typename This::Status
3288 thm_jump8(unsigned char *view,
3289 const Sized_relobj<32, big_endian>* object,
3290 const Symbol_value<32>* psymval,
3291 Arm_address address)
3293 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3294 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3295 Valtype* wv = reinterpret_cast<Valtype*>(view);
3296 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3297 Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
3298 Reltype x = (psymval->value(object, addend) - address);
3299 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
3300 return (utils::has_overflow<8>(x)
3301 ? This::STATUS_OVERFLOW
3302 : This::STATUS_OKAY);
3305 // R_ARM_THM_JUMP11: S + A – P
3306 static inline typename This::Status
3307 thm_jump11(unsigned char *view,
3308 const Sized_relobj<32, big_endian>* object,
3309 const Symbol_value<32>* psymval,
3310 Arm_address address)
3312 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3313 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3314 Valtype* wv = reinterpret_cast<Valtype*>(view);
3315 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3316 Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
3317 Reltype x = (psymval->value(object, addend) - address);
3318 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
3319 return (utils::has_overflow<11>(x)
3320 ? This::STATUS_OVERFLOW
3321 : This::STATUS_OKAY);
3324 // R_ARM_BASE_PREL: B(S) + A - P
3325 static inline typename This::Status
3326 base_prel(unsigned char* view,
3328 Arm_address address)
3330 Base::rel32(view, origin - address);
3334 // R_ARM_BASE_ABS: B(S) + A
3335 static inline typename This::Status
3336 base_abs(unsigned char* view,
3339 Base::rel32(view, origin);
3343 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3344 static inline typename This::Status
3345 got_brel(unsigned char* view,
3346 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3348 Base::rel32(view, got_offset);
3349 return This::STATUS_OKAY;
3352 // R_ARM_GOT_PREL: GOT(S) + A - P
3353 static inline typename This::Status
3354 got_prel(unsigned char *view,
3355 Arm_address got_entry,
3356 Arm_address address)
3358 Base::rel32(view, got_entry - address);
3359 return This::STATUS_OKAY;
3362 // R_ARM_PREL: (S + A) | T - P
3363 static inline typename This::Status
3364 prel31(unsigned char *view,
3365 const Sized_relobj<32, big_endian>* object,
3366 const Symbol_value<32>* psymval,
3367 Arm_address address,
3368 Arm_address thumb_bit)
3370 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3371 Valtype* wv = reinterpret_cast<Valtype*>(view);
3372 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3373 Valtype addend = utils::sign_extend<31>(val);
3374 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3375 val = utils::bit_select(val, x, 0x7fffffffU);
3376 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3377 return (utils::has_overflow<31>(x) ?
3378 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3381 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3382 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3383 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3384 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3385 static inline typename This::Status
3386 movw(unsigned char* view,
3387 const Sized_relobj<32, big_endian>* object,
3388 const Symbol_value<32>* psymval,
3389 Arm_address relative_address_base,
3390 Arm_address thumb_bit,
3391 bool check_overflow)
3393 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3394 Valtype* wv = reinterpret_cast<Valtype*>(view);
3395 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3396 Valtype addend = This::extract_arm_movw_movt_addend(val);
3397 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3398 - relative_address_base);
3399 val = This::insert_val_arm_movw_movt(val, x);
3400 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3401 return ((check_overflow && utils::has_overflow<16>(x))
3402 ? This::STATUS_OVERFLOW
3403 : This::STATUS_OKAY);
3406 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3407 // R_ARM_MOVT_PREL: S + A - P
3408 // R_ARM_MOVT_BREL: S + A - B(S)
3409 static inline typename This::Status
3410 movt(unsigned char* view,
3411 const Sized_relobj<32, big_endian>* object,
3412 const Symbol_value<32>* psymval,
3413 Arm_address relative_address_base)
3415 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3416 Valtype* wv = reinterpret_cast<Valtype*>(view);
3417 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3418 Valtype addend = This::extract_arm_movw_movt_addend(val);
3419 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3420 val = This::insert_val_arm_movw_movt(val, x);
3421 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3422 // FIXME: IHI0044D says that we should check for overflow.
3423 return This::STATUS_OKAY;
3426 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3427 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3428 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3429 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3430 static inline typename This::Status
3431 thm_movw(unsigned char *view,
3432 const Sized_relobj<32, big_endian>* object,
3433 const Symbol_value<32>* psymval,
3434 Arm_address relative_address_base,
3435 Arm_address thumb_bit,
3436 bool check_overflow)
3438 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3439 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3440 Valtype* wv = reinterpret_cast<Valtype*>(view);
3441 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3442 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3443 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3445 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3446 val = This::insert_val_thumb_movw_movt(val, x);
3447 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3448 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3449 return ((check_overflow && utils::has_overflow<16>(x))
3450 ? This::STATUS_OVERFLOW
3451 : This::STATUS_OKAY);
3454 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3455 // R_ARM_THM_MOVT_PREL: S + A - P
3456 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3457 static inline typename This::Status
3458 thm_movt(unsigned char* view,
3459 const Sized_relobj<32, big_endian>* object,
3460 const Symbol_value<32>* psymval,
3461 Arm_address relative_address_base)
3463 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3464 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3465 Valtype* wv = reinterpret_cast<Valtype*>(view);
3466 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3467 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3468 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3469 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3470 val = This::insert_val_thumb_movw_movt(val, x);
3471 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3472 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3473 return This::STATUS_OKAY;
3476 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3477 static inline typename This::Status
3478 thm_alu11(unsigned char* view,
3479 const Sized_relobj<32, big_endian>* object,
3480 const Symbol_value<32>* psymval,
3481 Arm_address address,
3482 Arm_address thumb_bit)
3484 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3485 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3486 Valtype* wv = reinterpret_cast<Valtype*>(view);
3487 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3488 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3490 // 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
3491 // -----------------------------------------------------------------------
3492 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3493 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3494 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3495 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3496 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3497 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3499 // Determine a sign for the addend.
3500 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3501 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3502 // Thumb2 addend encoding:
3503 // imm12 := i | imm3 | imm8
3504 int32_t addend = (insn & 0xff)
3505 | ((insn & 0x00007000) >> 4)
3506 | ((insn & 0x04000000) >> 15);
3507 // Apply a sign to the added.
3510 int32_t x = (psymval->value(object, addend) | thumb_bit)
3511 - (address & 0xfffffffc);
3512 Reltype val = abs(x);
3513 // Mask out the value and a distinct part of the ADD/SUB opcode
3514 // (bits 7:5 of opword).
3515 insn = (insn & 0xfb0f8f00)
3517 | ((val & 0x700) << 4)
3518 | ((val & 0x800) << 15);
3519 // Set the opcode according to whether the value to go in the
3520 // place is negative.
3524 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3525 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3526 return ((val > 0xfff) ?
3527 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3530 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3531 static inline typename This::Status
3532 thm_pc8(unsigned char* view,
3533 const Sized_relobj<32, big_endian>* object,
3534 const Symbol_value<32>* psymval,
3535 Arm_address address)
3537 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3538 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3539 Valtype* wv = reinterpret_cast<Valtype*>(view);
3540 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3541 Reltype addend = ((insn & 0x00ff) << 2);
3542 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3543 Reltype val = abs(x);
3544 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3546 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3547 return ((val > 0x03fc)
3548 ? This::STATUS_OVERFLOW
3549 : This::STATUS_OKAY);
3552 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3553 static inline typename This::Status
3554 thm_pc12(unsigned char* view,
3555 const Sized_relobj<32, big_endian>* object,
3556 const Symbol_value<32>* psymval,
3557 Arm_address address)
3559 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3560 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3561 Valtype* wv = reinterpret_cast<Valtype*>(view);
3562 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3563 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3564 // Determine a sign for the addend (positive if the U bit is 1).
3565 const int sign = (insn & 0x00800000) ? 1 : -1;
3566 int32_t addend = (insn & 0xfff);
3567 // Apply a sign to the added.
3570 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3571 Reltype val = abs(x);
3572 // Mask out and apply the value and the U bit.
3573 insn = (insn & 0xff7ff000) | (val & 0xfff);
3574 // Set the U bit according to whether the value to go in the
3575 // place is positive.
3579 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3580 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3581 return ((val > 0xfff) ?
3582 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3586 static inline typename This::Status
3587 v4bx(const Relocate_info<32, big_endian>* relinfo,
3588 unsigned char *view,
3589 const Arm_relobj<big_endian>* object,
3590 const Arm_address address,
3591 const bool is_interworking)
3594 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3595 Valtype* wv = reinterpret_cast<Valtype*>(view);
3596 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3598 // Ensure that we have a BX instruction.
3599 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3600 const uint32_t reg = (val & 0xf);
3601 if (is_interworking && reg != 0xf)
3603 Stub_table<big_endian>* stub_table =
3604 object->stub_table(relinfo->data_shndx);
3605 gold_assert(stub_table != NULL);
3607 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3608 gold_assert(stub != NULL);
3610 int32_t veneer_address =
3611 stub_table->address() + stub->offset() - 8 - address;
3612 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3613 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3614 // Replace with a branch to veneer (B <addr>)
3615 val = (val & 0xf0000000) | 0x0a000000
3616 | ((veneer_address >> 2) & 0x00ffffff);
3620 // Preserve Rm (lowest four bits) and the condition code
3621 // (highest four bits). Other bits encode MOV PC,Rm.
3622 val = (val & 0xf000000f) | 0x01a0f000;
3624 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3625 return This::STATUS_OKAY;
3628 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3629 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3630 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3631 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3632 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3633 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3634 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3635 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3636 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3637 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3638 static inline typename This::Status
3639 arm_grp_alu(unsigned char* view,
3640 const Sized_relobj<32, big_endian>* object,
3641 const Symbol_value<32>* psymval,
3643 Arm_address address,
3644 Arm_address thumb_bit,
3645 bool check_overflow)
3647 gold_assert(group >= 0 && group < 3);
3648 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3649 Valtype* wv = reinterpret_cast<Valtype*>(view);
3650 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3652 // ALU group relocations are allowed only for the ADD/SUB instructions.
3653 // (0x00800000 - ADD, 0x00400000 - SUB)
3654 const Valtype opcode = insn & 0x01e00000;
3655 if (opcode != 0x00800000 && opcode != 0x00400000)
3656 return This::STATUS_BAD_RELOC;
3658 // Determine a sign for the addend.
3659 const int sign = (opcode == 0x00800000) ? 1 : -1;
3660 // shifter = rotate_imm * 2
3661 const uint32_t shifter = (insn & 0xf00) >> 7;
3662 // Initial addend value.
3663 int32_t addend = insn & 0xff;
3664 // Rotate addend right by shifter.
3665 addend = (addend >> shifter) | (addend << (32 - shifter));
3666 // Apply a sign to the added.
3669 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3670 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3671 // Check for overflow if required
3673 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3674 return This::STATUS_OVERFLOW;
3676 // Mask out the value and the ADD/SUB part of the opcode; take care
3677 // not to destroy the S bit.
3679 // Set the opcode according to whether the value to go in the
3680 // place is negative.
3681 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3682 // Encode the offset (encoded Gn).
3685 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3686 return This::STATUS_OKAY;
3689 // R_ARM_LDR_PC_G0: S + A - P
3690 // R_ARM_LDR_PC_G1: S + A - P
3691 // R_ARM_LDR_PC_G2: S + A - P
3692 // R_ARM_LDR_SB_G0: S + A - B(S)
3693 // R_ARM_LDR_SB_G1: S + A - B(S)
3694 // R_ARM_LDR_SB_G2: S + A - B(S)
3695 static inline typename This::Status
3696 arm_grp_ldr(unsigned char* view,
3697 const Sized_relobj<32, big_endian>* object,
3698 const Symbol_value<32>* psymval,
3700 Arm_address address)
3702 gold_assert(group >= 0 && group < 3);
3703 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3704 Valtype* wv = reinterpret_cast<Valtype*>(view);
3705 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3707 const int sign = (insn & 0x00800000) ? 1 : -1;
3708 int32_t addend = (insn & 0xfff) * sign;
3709 int32_t x = (psymval->value(object, addend) - address);
3710 // Calculate the relevant G(n-1) value to obtain this stage residual.
3712 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3713 if (residual >= 0x1000)
3714 return This::STATUS_OVERFLOW;
3716 // Mask out the value and U bit.
3718 // Set the U bit for non-negative values.
3723 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3724 return This::STATUS_OKAY;
3727 // R_ARM_LDRS_PC_G0: S + A - P
3728 // R_ARM_LDRS_PC_G1: S + A - P
3729 // R_ARM_LDRS_PC_G2: S + A - P
3730 // R_ARM_LDRS_SB_G0: S + A - B(S)
3731 // R_ARM_LDRS_SB_G1: S + A - B(S)
3732 // R_ARM_LDRS_SB_G2: S + A - B(S)
3733 static inline typename This::Status
3734 arm_grp_ldrs(unsigned char* view,
3735 const Sized_relobj<32, big_endian>* object,
3736 const Symbol_value<32>* psymval,
3738 Arm_address address)
3740 gold_assert(group >= 0 && group < 3);
3741 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3742 Valtype* wv = reinterpret_cast<Valtype*>(view);
3743 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3745 const int sign = (insn & 0x00800000) ? 1 : -1;
3746 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3747 int32_t x = (psymval->value(object, addend) - address);
3748 // Calculate the relevant G(n-1) value to obtain this stage residual.
3750 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3751 if (residual >= 0x100)
3752 return This::STATUS_OVERFLOW;
3754 // Mask out the value and U bit.
3756 // Set the U bit for non-negative values.
3759 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3761 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3762 return This::STATUS_OKAY;
3765 // R_ARM_LDC_PC_G0: S + A - P
3766 // R_ARM_LDC_PC_G1: S + A - P
3767 // R_ARM_LDC_PC_G2: S + A - P
3768 // R_ARM_LDC_SB_G0: S + A - B(S)
3769 // R_ARM_LDC_SB_G1: S + A - B(S)
3770 // R_ARM_LDC_SB_G2: S + A - B(S)
3771 static inline typename This::Status
3772 arm_grp_ldc(unsigned char* view,
3773 const Sized_relobj<32, big_endian>* object,
3774 const Symbol_value<32>* psymval,
3776 Arm_address address)
3778 gold_assert(group >= 0 && group < 3);
3779 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3780 Valtype* wv = reinterpret_cast<Valtype*>(view);
3781 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3783 const int sign = (insn & 0x00800000) ? 1 : -1;
3784 int32_t addend = ((insn & 0xff) << 2) * sign;
3785 int32_t x = (psymval->value(object, addend) - address);
3786 // Calculate the relevant G(n-1) value to obtain this stage residual.
3788 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3789 if ((residual & 0x3) != 0 || residual >= 0x400)
3790 return This::STATUS_OVERFLOW;
3792 // Mask out the value and U bit.
3794 // Set the U bit for non-negative values.
3797 insn |= (residual >> 2);
3799 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3800 return This::STATUS_OKAY;
3804 // Relocate ARM long branches. This handles relocation types
3805 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3806 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3807 // undefined and we do not use PLT in this relocation. In such a case,
3808 // the branch is converted into an NOP.
3810 template<bool big_endian>
3811 typename Arm_relocate_functions<big_endian>::Status
3812 Arm_relocate_functions<big_endian>::arm_branch_common(
3813 unsigned int r_type,
3814 const Relocate_info<32, big_endian>* relinfo,
3815 unsigned char *view,
3816 const Sized_symbol<32>* gsym,
3817 const Arm_relobj<big_endian>* object,
3819 const Symbol_value<32>* psymval,
3820 Arm_address address,
3821 Arm_address thumb_bit,
3822 bool is_weakly_undefined_without_plt)
3824 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3825 Valtype* wv = reinterpret_cast<Valtype*>(view);
3826 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3828 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3829 && ((val & 0x0f000000UL) == 0x0a000000UL);
3830 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3831 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3832 && ((val & 0x0f000000UL) == 0x0b000000UL);
3833 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3834 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3836 // Check that the instruction is valid.
3837 if (r_type == elfcpp::R_ARM_CALL)
3839 if (!insn_is_uncond_bl && !insn_is_blx)
3840 return This::STATUS_BAD_RELOC;
3842 else if (r_type == elfcpp::R_ARM_JUMP24)
3844 if (!insn_is_b && !insn_is_cond_bl)
3845 return This::STATUS_BAD_RELOC;
3847 else if (r_type == elfcpp::R_ARM_PLT32)
3849 if (!insn_is_any_branch)
3850 return This::STATUS_BAD_RELOC;
3852 else if (r_type == elfcpp::R_ARM_XPC25)
3854 // FIXME: AAELF document IH0044C does not say much about it other
3855 // than it being obsolete.
3856 if (!insn_is_any_branch)
3857 return This::STATUS_BAD_RELOC;
3862 // A branch to an undefined weak symbol is turned into a jump to
3863 // the next instruction unless a PLT entry will be created.
3864 // Do the same for local undefined symbols.
3865 // The jump to the next instruction is optimized as a NOP depending
3866 // on the architecture.
3867 const Target_arm<big_endian>* arm_target =
3868 Target_arm<big_endian>::default_target();
3869 if (is_weakly_undefined_without_plt)
3871 gold_assert(!parameters->options().relocatable());
3872 Valtype cond = val & 0xf0000000U;
3873 if (arm_target->may_use_arm_nop())
3874 val = cond | 0x0320f000;
3876 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3877 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3878 return This::STATUS_OKAY;
3881 Valtype addend = utils::sign_extend<26>(val << 2);
3882 Valtype branch_target = psymval->value(object, addend);
3883 int32_t branch_offset = branch_target - address;
3885 // We need a stub if the branch offset is too large or if we need
3887 bool may_use_blx = arm_target->may_use_blx();
3888 Reloc_stub* stub = NULL;
3890 if (!parameters->options().relocatable()
3891 && (utils::has_overflow<26>(branch_offset)
3892 || ((thumb_bit != 0)
3893 && !(may_use_blx && r_type == elfcpp::R_ARM_CALL))))
3895 Valtype unadjusted_branch_target = psymval->value(object, 0);
3897 Stub_type stub_type =
3898 Reloc_stub::stub_type_for_reloc(r_type, address,
3899 unadjusted_branch_target,
3901 if (stub_type != arm_stub_none)
3903 Stub_table<big_endian>* stub_table =
3904 object->stub_table(relinfo->data_shndx);
3905 gold_assert(stub_table != NULL);
3907 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3908 stub = stub_table->find_reloc_stub(stub_key);
3909 gold_assert(stub != NULL);
3910 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3911 branch_target = stub_table->address() + stub->offset() + addend;
3912 branch_offset = branch_target - address;
3913 gold_assert(!utils::has_overflow<26>(branch_offset));
3917 // At this point, if we still need to switch mode, the instruction
3918 // must either be a BLX or a BL that can be converted to a BLX.
3922 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3923 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3926 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
3927 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3928 return (utils::has_overflow<26>(branch_offset)
3929 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
3932 // Relocate THUMB long branches. This handles relocation types
3933 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3934 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3935 // undefined and we do not use PLT in this relocation. In such a case,
3936 // the branch is converted into an NOP.
3938 template<bool big_endian>
3939 typename Arm_relocate_functions<big_endian>::Status
3940 Arm_relocate_functions<big_endian>::thumb_branch_common(
3941 unsigned int r_type,
3942 const Relocate_info<32, big_endian>* relinfo,
3943 unsigned char *view,
3944 const Sized_symbol<32>* gsym,
3945 const Arm_relobj<big_endian>* object,
3947 const Symbol_value<32>* psymval,
3948 Arm_address address,
3949 Arm_address thumb_bit,
3950 bool is_weakly_undefined_without_plt)
3952 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3953 Valtype* wv = reinterpret_cast<Valtype*>(view);
3954 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3955 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3957 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3959 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
3960 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
3962 // Check that the instruction is valid.
3963 if (r_type == elfcpp::R_ARM_THM_CALL)
3965 if (!is_bl_insn && !is_blx_insn)
3966 return This::STATUS_BAD_RELOC;
3968 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
3970 // This cannot be a BLX.
3972 return This::STATUS_BAD_RELOC;
3974 else if (r_type == elfcpp::R_ARM_THM_XPC22)
3976 // Check for Thumb to Thumb call.
3978 return This::STATUS_BAD_RELOC;
3981 gold_warning(_("%s: Thumb BLX instruction targets "
3982 "thumb function '%s'."),
3983 object->name().c_str(),
3984 (gsym ? gsym->name() : "(local)"));
3985 // Convert BLX to BL.
3986 lower_insn |= 0x1000U;
3992 // A branch to an undefined weak symbol is turned into a jump to
3993 // the next instruction unless a PLT entry will be created.
3994 // The jump to the next instruction is optimized as a NOP.W for
3995 // Thumb-2 enabled architectures.
3996 const Target_arm<big_endian>* arm_target =
3997 Target_arm<big_endian>::default_target();
3998 if (is_weakly_undefined_without_plt)
4000 gold_assert(!parameters->options().relocatable());
4001 if (arm_target->may_use_thumb2_nop())
4003 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
4004 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
4008 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
4009 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
4011 return This::STATUS_OKAY;
4014 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
4015 Arm_address branch_target = psymval->value(object, addend);
4017 // For BLX, bit 1 of target address comes from bit 1 of base address.
4018 bool may_use_blx = arm_target->may_use_blx();
4019 if (thumb_bit == 0 && may_use_blx)
4020 branch_target = utils::bit_select(branch_target, address, 0x2);
4022 int32_t branch_offset = branch_target - address;
4024 // We need a stub if the branch offset is too large or if we need
4026 bool thumb2 = arm_target->using_thumb2();
4027 if (!parameters->options().relocatable()
4028 && ((!thumb2 && utils::has_overflow<23>(branch_offset))
4029 || (thumb2 && utils::has_overflow<25>(branch_offset))
4030 || ((thumb_bit == 0)
4031 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4032 || r_type == elfcpp::R_ARM_THM_JUMP24))))
4034 Arm_address unadjusted_branch_target = psymval->value(object, 0);
4036 Stub_type stub_type =
4037 Reloc_stub::stub_type_for_reloc(r_type, address,
4038 unadjusted_branch_target,
4041 if (stub_type != arm_stub_none)
4043 Stub_table<big_endian>* stub_table =
4044 object->stub_table(relinfo->data_shndx);
4045 gold_assert(stub_table != NULL);
4047 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
4048 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
4049 gold_assert(stub != NULL);
4050 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
4051 branch_target = stub_table->address() + stub->offset() + addend;
4052 if (thumb_bit == 0 && may_use_blx)
4053 branch_target = utils::bit_select(branch_target, address, 0x2);
4054 branch_offset = branch_target - address;
4058 // At this point, if we still need to switch mode, the instruction
4059 // must either be a BLX or a BL that can be converted to a BLX.
4062 gold_assert(may_use_blx
4063 && (r_type == elfcpp::R_ARM_THM_CALL
4064 || r_type == elfcpp::R_ARM_THM_XPC22));
4065 // Make sure this is a BLX.
4066 lower_insn &= ~0x1000U;
4070 // Make sure this is a BL.
4071 lower_insn |= 0x1000U;
4074 // For a BLX instruction, make sure that the relocation is rounded up
4075 // to a word boundary. This follows the semantics of the instruction
4076 // which specifies that bit 1 of the target address will come from bit
4077 // 1 of the base address.
4078 if ((lower_insn & 0x5000U) == 0x4000U)
4079 gold_assert((branch_offset & 3) == 0);
4081 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
4082 // We use the Thumb-2 encoding, which is safe even if dealing with
4083 // a Thumb-1 instruction by virtue of our overflow check above. */
4084 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
4085 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
4087 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4088 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4090 gold_assert(!utils::has_overflow<25>(branch_offset));
4093 ? utils::has_overflow<25>(branch_offset)
4094 : utils::has_overflow<23>(branch_offset))
4095 ? This::STATUS_OVERFLOW
4096 : This::STATUS_OKAY);
4099 // Relocate THUMB-2 long conditional branches.
4100 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
4101 // undefined and we do not use PLT in this relocation. In such a case,
4102 // the branch is converted into an NOP.
4104 template<bool big_endian>
4105 typename Arm_relocate_functions<big_endian>::Status
4106 Arm_relocate_functions<big_endian>::thm_jump19(
4107 unsigned char *view,
4108 const Arm_relobj<big_endian>* object,
4109 const Symbol_value<32>* psymval,
4110 Arm_address address,
4111 Arm_address thumb_bit)
4113 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
4114 Valtype* wv = reinterpret_cast<Valtype*>(view);
4115 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
4116 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
4117 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
4119 Arm_address branch_target = psymval->value(object, addend);
4120 int32_t branch_offset = branch_target - address;
4122 // ??? Should handle interworking? GCC might someday try to
4123 // use this for tail calls.
4124 // FIXME: We do support thumb entry to PLT yet.
4127 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
4128 return This::STATUS_BAD_RELOC;
4131 // Put RELOCATION back into the insn.
4132 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
4133 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
4135 // Put the relocated value back in the object file:
4136 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4137 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4139 return (utils::has_overflow<21>(branch_offset)
4140 ? This::STATUS_OVERFLOW
4141 : This::STATUS_OKAY);
4144 // Get the GOT section, creating it if necessary.
4146 template<bool big_endian>
4147 Arm_output_data_got<big_endian>*
4148 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
4150 if (this->got_ == NULL)
4152 gold_assert(symtab != NULL && layout != NULL);
4154 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
4156 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4158 | elfcpp::SHF_WRITE),
4159 this->got_, ORDER_RELRO, true);
4161 // The old GNU linker creates a .got.plt section. We just
4162 // create another set of data in the .got section. Note that we
4163 // always create a PLT if we create a GOT, although the PLT
4165 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
4166 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4168 | elfcpp::SHF_WRITE),
4169 this->got_plt_, ORDER_DATA, false);
4171 // The first three entries are reserved.
4172 this->got_plt_->set_current_data_size(3 * 4);
4174 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
4175 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
4176 Symbol_table::PREDEFINED,
4178 0, 0, elfcpp::STT_OBJECT,
4180 elfcpp::STV_HIDDEN, 0,
4186 // Get the dynamic reloc section, creating it if necessary.
4188 template<bool big_endian>
4189 typename Target_arm<big_endian>::Reloc_section*
4190 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
4192 if (this->rel_dyn_ == NULL)
4194 gold_assert(layout != NULL);
4195 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
4196 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
4197 elfcpp::SHF_ALLOC, this->rel_dyn_,
4198 ORDER_DYNAMIC_RELOCS, false);
4200 return this->rel_dyn_;
4203 // Insn_template methods.
4205 // Return byte size of an instruction template.
4208 Insn_template::size() const
4210 switch (this->type())
4213 case THUMB16_SPECIAL_TYPE:
4224 // Return alignment of an instruction template.
4227 Insn_template::alignment() const
4229 switch (this->type())
4232 case THUMB16_SPECIAL_TYPE:
4243 // Stub_template methods.
4245 Stub_template::Stub_template(
4246 Stub_type type, const Insn_template* insns,
4248 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4249 entry_in_thumb_mode_(false), relocs_()
4253 // Compute byte size and alignment of stub template.
4254 for (size_t i = 0; i < insn_count; i++)
4256 unsigned insn_alignment = insns[i].alignment();
4257 size_t insn_size = insns[i].size();
4258 gold_assert((offset & (insn_alignment - 1)) == 0);
4259 this->alignment_ = std::max(this->alignment_, insn_alignment);
4260 switch (insns[i].type())
4262 case Insn_template::THUMB16_TYPE:
4263 case Insn_template::THUMB16_SPECIAL_TYPE:
4265 this->entry_in_thumb_mode_ = true;
4268 case Insn_template::THUMB32_TYPE:
4269 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4270 this->relocs_.push_back(Reloc(i, offset));
4272 this->entry_in_thumb_mode_ = true;
4275 case Insn_template::ARM_TYPE:
4276 // Handle cases where the target is encoded within the
4278 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4279 this->relocs_.push_back(Reloc(i, offset));
4282 case Insn_template::DATA_TYPE:
4283 // Entry point cannot be data.
4284 gold_assert(i != 0);
4285 this->relocs_.push_back(Reloc(i, offset));
4291 offset += insn_size;
4293 this->size_ = offset;
4298 // Template to implement do_write for a specific target endianness.
4300 template<bool big_endian>
4302 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4304 const Stub_template* stub_template = this->stub_template();
4305 const Insn_template* insns = stub_template->insns();
4307 // FIXME: We do not handle BE8 encoding yet.
4308 unsigned char* pov = view;
4309 for (size_t i = 0; i < stub_template->insn_count(); i++)
4311 switch (insns[i].type())
4313 case Insn_template::THUMB16_TYPE:
4314 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4316 case Insn_template::THUMB16_SPECIAL_TYPE:
4317 elfcpp::Swap<16, big_endian>::writeval(
4319 this->thumb16_special(i));
4321 case Insn_template::THUMB32_TYPE:
4323 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4324 uint32_t lo = insns[i].data() & 0xffff;
4325 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4326 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4329 case Insn_template::ARM_TYPE:
4330 case Insn_template::DATA_TYPE:
4331 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4336 pov += insns[i].size();
4338 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4341 // Reloc_stub::Key methods.
4343 // Dump a Key as a string for debugging.
4346 Reloc_stub::Key::name() const
4348 if (this->r_sym_ == invalid_index)
4350 // Global symbol key name
4351 // <stub-type>:<symbol name>:<addend>.
4352 const std::string sym_name = this->u_.symbol->name();
4353 // We need to print two hex number and two colons. So just add 100 bytes
4354 // to the symbol name size.
4355 size_t len = sym_name.size() + 100;
4356 char* buffer = new char[len];
4357 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4358 sym_name.c_str(), this->addend_);
4359 gold_assert(c > 0 && c < static_cast<int>(len));
4361 return std::string(buffer);
4365 // local symbol key name
4366 // <stub-type>:<object>:<r_sym>:<addend>.
4367 const size_t len = 200;
4369 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4370 this->u_.relobj, this->r_sym_, this->addend_);
4371 gold_assert(c > 0 && c < static_cast<int>(len));
4372 return std::string(buffer);
4376 // Reloc_stub methods.
4378 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4379 // LOCATION to DESTINATION.
4380 // This code is based on the arm_type_of_stub function in
4381 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
4385 Reloc_stub::stub_type_for_reloc(
4386 unsigned int r_type,
4387 Arm_address location,
4388 Arm_address destination,
4389 bool target_is_thumb)
4391 Stub_type stub_type = arm_stub_none;
4393 // This is a bit ugly but we want to avoid using a templated class for
4394 // big and little endianities.
4396 bool should_force_pic_veneer;
4399 if (parameters->target().is_big_endian())
4401 const Target_arm<true>* big_endian_target =
4402 Target_arm<true>::default_target();
4403 may_use_blx = big_endian_target->may_use_blx();
4404 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4405 thumb2 = big_endian_target->using_thumb2();
4406 thumb_only = big_endian_target->using_thumb_only();
4410 const Target_arm<false>* little_endian_target =
4411 Target_arm<false>::default_target();
4412 may_use_blx = little_endian_target->may_use_blx();
4413 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4414 thumb2 = little_endian_target->using_thumb2();
4415 thumb_only = little_endian_target->using_thumb_only();
4418 int64_t branch_offset;
4419 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4421 // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
4422 // base address (instruction address + 4).
4423 if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
4424 destination = utils::bit_select(destination, location, 0x2);
4425 branch_offset = static_cast<int64_t>(destination) - location;
4427 // Handle cases where:
4428 // - this call goes too far (different Thumb/Thumb2 max
4430 // - it's a Thumb->Arm call and blx is not available, or it's a
4431 // Thumb->Arm branch (not bl). A stub is needed in this case.
4433 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4434 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4436 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4437 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4438 || ((!target_is_thumb)
4439 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4440 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4442 if (target_is_thumb)
4447 stub_type = (parameters->options().shared()
4448 || should_force_pic_veneer)
4451 && (r_type == elfcpp::R_ARM_THM_CALL))
4452 // V5T and above. Stub starts with ARM code, so
4453 // we must be able to switch mode before
4454 // reaching it, which is only possible for 'bl'
4455 // (ie R_ARM_THM_CALL relocation).
4456 ? arm_stub_long_branch_any_thumb_pic
4457 // On V4T, use Thumb code only.
4458 : arm_stub_long_branch_v4t_thumb_thumb_pic)
4462 && (r_type == elfcpp::R_ARM_THM_CALL))
4463 ? arm_stub_long_branch_any_any // V5T and above.
4464 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
4468 stub_type = (parameters->options().shared()
4469 || should_force_pic_veneer)
4470 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4471 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4478 // FIXME: We should check that the input section is from an
4479 // object that has interwork enabled.
4481 stub_type = (parameters->options().shared()
4482 || should_force_pic_veneer)
4485 && (r_type == elfcpp::R_ARM_THM_CALL))
4486 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4487 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4491 && (r_type == elfcpp::R_ARM_THM_CALL))
4492 ? arm_stub_long_branch_any_any // V5T and above.
4493 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4495 // Handle v4t short branches.
4496 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4497 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4498 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4499 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4503 else if (r_type == elfcpp::R_ARM_CALL
4504 || r_type == elfcpp::R_ARM_JUMP24
4505 || r_type == elfcpp::R_ARM_PLT32)
4507 branch_offset = static_cast<int64_t>(destination) - location;
4508 if (target_is_thumb)
4512 // FIXME: We should check that the input section is from an
4513 // object that has interwork enabled.
4515 // We have an extra 2-bytes reach because of
4516 // the mode change (bit 24 (H) of BLX encoding).
4517 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4518 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4519 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4520 || (r_type == elfcpp::R_ARM_JUMP24)
4521 || (r_type == elfcpp::R_ARM_PLT32))
4523 stub_type = (parameters->options().shared()
4524 || should_force_pic_veneer)
4527 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4528 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4532 ? arm_stub_long_branch_any_any // V5T and above.
4533 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4539 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4540 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4542 stub_type = (parameters->options().shared()
4543 || should_force_pic_veneer)
4544 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4545 : arm_stub_long_branch_any_any; /// non-PIC.
4553 // Cortex_a8_stub methods.
4555 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4556 // I is the position of the instruction template in the stub template.
4559 Cortex_a8_stub::do_thumb16_special(size_t i)
4561 // The only use of this is to copy condition code from a conditional
4562 // branch being worked around to the corresponding conditional branch in
4564 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4566 uint16_t data = this->stub_template()->insns()[i].data();
4567 gold_assert((data & 0xff00U) == 0xd000U);
4568 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4572 // Stub_factory methods.
4574 Stub_factory::Stub_factory()
4576 // The instruction template sequences are declared as static
4577 // objects and initialized first time the constructor runs.
4579 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4580 // to reach the stub if necessary.
4581 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4583 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4584 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4585 // dcd R_ARM_ABS32(X)
4588 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4590 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4592 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4593 Insn_template::arm_insn(0xe12fff1c), // bx ip
4594 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4595 // dcd R_ARM_ABS32(X)
4598 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4599 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4601 Insn_template::thumb16_insn(0xb401), // push {r0}
4602 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4603 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4604 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4605 Insn_template::thumb16_insn(0x4760), // bx ip
4606 Insn_template::thumb16_insn(0xbf00), // nop
4607 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4608 // dcd R_ARM_ABS32(X)
4611 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4613 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4615 Insn_template::thumb16_insn(0x4778), // bx pc
4616 Insn_template::thumb16_insn(0x46c0), // nop
4617 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4618 Insn_template::arm_insn(0xe12fff1c), // bx ip
4619 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4620 // dcd R_ARM_ABS32(X)
4623 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4625 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4627 Insn_template::thumb16_insn(0x4778), // bx pc
4628 Insn_template::thumb16_insn(0x46c0), // nop
4629 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4630 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4631 // dcd R_ARM_ABS32(X)
4634 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4635 // one, when the destination is close enough.
4636 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4638 Insn_template::thumb16_insn(0x4778), // bx pc
4639 Insn_template::thumb16_insn(0x46c0), // nop
4640 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4643 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4644 // blx to reach the stub if necessary.
4645 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4647 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4648 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4649 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4650 // dcd R_ARM_REL32(X-4)
4653 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4654 // blx to reach the stub if necessary. We can not add into pc;
4655 // it is not guaranteed to mode switch (different in ARMv6 and
4657 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4659 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4660 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4661 Insn_template::arm_insn(0xe12fff1c), // bx ip
4662 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4663 // dcd R_ARM_REL32(X)
4666 // V4T ARM -> ARM long branch stub, PIC.
4667 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4669 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4670 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4671 Insn_template::arm_insn(0xe12fff1c), // bx ip
4672 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4673 // dcd R_ARM_REL32(X)
4676 // V4T Thumb -> ARM long branch stub, PIC.
4677 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4679 Insn_template::thumb16_insn(0x4778), // bx pc
4680 Insn_template::thumb16_insn(0x46c0), // nop
4681 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4682 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4683 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4684 // dcd R_ARM_REL32(X)
4687 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4689 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4691 Insn_template::thumb16_insn(0xb401), // push {r0}
4692 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4693 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4694 Insn_template::thumb16_insn(0x4484), // add ip, r0
4695 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4696 Insn_template::thumb16_insn(0x4760), // bx ip
4697 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4698 // dcd R_ARM_REL32(X)
4701 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4703 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4705 Insn_template::thumb16_insn(0x4778), // bx pc
4706 Insn_template::thumb16_insn(0x46c0), // nop
4707 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4708 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4709 Insn_template::arm_insn(0xe12fff1c), // bx ip
4710 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4711 // dcd R_ARM_REL32(X)
4714 // Cortex-A8 erratum-workaround stubs.
4716 // Stub used for conditional branches (which may be beyond +/-1MB away,
4717 // so we can't use a conditional branch to reach this stub).
4724 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4726 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4727 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4728 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4732 // Stub used for b.w and bl.w instructions.
4734 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4736 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4739 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4741 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4744 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4745 // instruction (which switches to ARM mode) to point to this stub. Jump to
4746 // the real destination using an ARM-mode branch.
4747 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4749 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4752 // Stub used to provide an interworking for R_ARM_V4BX relocation
4753 // (bx r[n] instruction).
4754 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4756 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4757 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4758 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4761 // Fill in the stub template look-up table. Stub templates are constructed
4762 // per instance of Stub_factory for fast look-up without locking
4763 // in a thread-enabled environment.
4765 this->stub_templates_[arm_stub_none] =
4766 new Stub_template(arm_stub_none, NULL, 0);
4768 #define DEF_STUB(x) \
4772 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4773 Stub_type type = arm_stub_##x; \
4774 this->stub_templates_[type] = \
4775 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4783 // Stub_table methods.
4785 // Removel all Cortex-A8 stub.
4787 template<bool big_endian>
4789 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4791 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4792 p != this->cortex_a8_stubs_.end();
4795 this->cortex_a8_stubs_.clear();
4798 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4800 template<bool big_endian>
4802 Stub_table<big_endian>::relocate_stub(
4804 const Relocate_info<32, big_endian>* relinfo,
4805 Target_arm<big_endian>* arm_target,
4806 Output_section* output_section,
4807 unsigned char* view,
4808 Arm_address address,
4809 section_size_type view_size)
4811 const Stub_template* stub_template = stub->stub_template();
4812 if (stub_template->reloc_count() != 0)
4814 // Adjust view to cover the stub only.
4815 section_size_type offset = stub->offset();
4816 section_size_type stub_size = stub_template->size();
4817 gold_assert(offset + stub_size <= view_size);
4819 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4820 address + offset, stub_size);
4824 // Relocate all stubs in this stub table.
4826 template<bool big_endian>
4828 Stub_table<big_endian>::relocate_stubs(
4829 const Relocate_info<32, big_endian>* relinfo,
4830 Target_arm<big_endian>* arm_target,
4831 Output_section* output_section,
4832 unsigned char* view,
4833 Arm_address address,
4834 section_size_type view_size)
4836 // If we are passed a view bigger than the stub table's. we need to
4838 gold_assert(address == this->address()
4840 == static_cast<section_size_type>(this->data_size())));
4842 // Relocate all relocation stubs.
4843 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4844 p != this->reloc_stubs_.end();
4846 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4847 address, view_size);
4849 // Relocate all Cortex-A8 stubs.
4850 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4851 p != this->cortex_a8_stubs_.end();
4853 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4854 address, view_size);
4856 // Relocate all ARM V4BX stubs.
4857 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4858 p != this->arm_v4bx_stubs_.end();
4862 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4863 address, view_size);
4867 // Write out the stubs to file.
4869 template<bool big_endian>
4871 Stub_table<big_endian>::do_write(Output_file* of)
4873 off_t offset = this->offset();
4874 const section_size_type oview_size =
4875 convert_to_section_size_type(this->data_size());
4876 unsigned char* const oview = of->get_output_view(offset, oview_size);
4878 // Write relocation stubs.
4879 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4880 p != this->reloc_stubs_.end();
4883 Reloc_stub* stub = p->second;
4884 Arm_address address = this->address() + stub->offset();
4886 == align_address(address,
4887 stub->stub_template()->alignment()));
4888 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4892 // Write Cortex-A8 stubs.
4893 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4894 p != this->cortex_a8_stubs_.end();
4897 Cortex_a8_stub* stub = p->second;
4898 Arm_address address = this->address() + stub->offset();
4900 == align_address(address,
4901 stub->stub_template()->alignment()));
4902 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4906 // Write ARM V4BX relocation stubs.
4907 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4908 p != this->arm_v4bx_stubs_.end();
4914 Arm_address address = this->address() + (*p)->offset();
4916 == align_address(address,
4917 (*p)->stub_template()->alignment()));
4918 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4922 of->write_output_view(this->offset(), oview_size, oview);
4925 // Update the data size and address alignment of the stub table at the end
4926 // of a relaxation pass. Return true if either the data size or the
4927 // alignment changed in this relaxation pass.
4929 template<bool big_endian>
4931 Stub_table<big_endian>::update_data_size_and_addralign()
4933 // Go over all stubs in table to compute data size and address alignment.
4934 off_t size = this->reloc_stubs_size_;
4935 unsigned addralign = this->reloc_stubs_addralign_;
4937 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4938 p != this->cortex_a8_stubs_.end();
4941 const Stub_template* stub_template = p->second->stub_template();
4942 addralign = std::max(addralign, stub_template->alignment());
4943 size = (align_address(size, stub_template->alignment())
4944 + stub_template->size());
4947 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4948 p != this->arm_v4bx_stubs_.end();
4954 const Stub_template* stub_template = (*p)->stub_template();
4955 addralign = std::max(addralign, stub_template->alignment());
4956 size = (align_address(size, stub_template->alignment())
4957 + stub_template->size());
4960 // Check if either data size or alignment changed in this pass.
4961 // Update prev_data_size_ and prev_addralign_. These will be used
4962 // as the current data size and address alignment for the next pass.
4963 bool changed = size != this->prev_data_size_;
4964 this->prev_data_size_ = size;
4966 if (addralign != this->prev_addralign_)
4968 this->prev_addralign_ = addralign;
4973 // Finalize the stubs. This sets the offsets of the stubs within the stub
4974 // table. It also marks all input sections needing Cortex-A8 workaround.
4976 template<bool big_endian>
4978 Stub_table<big_endian>::finalize_stubs()
4980 off_t off = this->reloc_stubs_size_;
4981 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4982 p != this->cortex_a8_stubs_.end();
4985 Cortex_a8_stub* stub = p->second;
4986 const Stub_template* stub_template = stub->stub_template();
4987 uint64_t stub_addralign = stub_template->alignment();
4988 off = align_address(off, stub_addralign);
4989 stub->set_offset(off);
4990 off += stub_template->size();
4992 // Mark input section so that we can determine later if a code section
4993 // needs the Cortex-A8 workaround quickly.
4994 Arm_relobj<big_endian>* arm_relobj =
4995 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
4996 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
4999 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
5000 p != this->arm_v4bx_stubs_.end();
5006 const Stub_template* stub_template = (*p)->stub_template();
5007 uint64_t stub_addralign = stub_template->alignment();
5008 off = align_address(off, stub_addralign);
5009 (*p)->set_offset(off);
5010 off += stub_template->size();
5013 gold_assert(off <= this->prev_data_size_);
5016 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
5017 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
5018 // of the address range seen by the linker.
5020 template<bool big_endian>
5022 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
5023 Target_arm<big_endian>* arm_target,
5024 unsigned char* view,
5025 Arm_address view_address,
5026 section_size_type view_size)
5028 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
5029 for (Cortex_a8_stub_list::const_iterator p =
5030 this->cortex_a8_stubs_.lower_bound(view_address);
5031 ((p != this->cortex_a8_stubs_.end())
5032 && (p->first < (view_address + view_size)));
5035 // We do not store the THUMB bit in the LSB of either the branch address
5036 // or the stub offset. There is no need to strip the LSB.
5037 Arm_address branch_address = p->first;
5038 const Cortex_a8_stub* stub = p->second;
5039 Arm_address stub_address = this->address() + stub->offset();
5041 // Offset of the branch instruction relative to this view.
5042 section_size_type offset =
5043 convert_to_section_size_type(branch_address - view_address);
5044 gold_assert((offset + 4) <= view_size);
5046 arm_target->apply_cortex_a8_workaround(stub, stub_address,
5047 view + offset, branch_address);
5051 // Arm_input_section methods.
5053 // Initialize an Arm_input_section.
5055 template<bool big_endian>
5057 Arm_input_section<big_endian>::init()
5059 Relobj* relobj = this->relobj();
5060 unsigned int shndx = this->shndx();
5062 // Cache these to speed up size and alignment queries. It is too slow
5063 // to call section_addraglin and section_size every time.
5064 this->original_addralign_ =
5065 convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
5066 this->original_size_ =
5067 convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
5069 // We want to make this look like the original input section after
5070 // output sections are finalized.
5071 Output_section* os = relobj->output_section(shndx);
5072 off_t offset = relobj->output_section_offset(shndx);
5073 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
5074 this->set_address(os->address() + offset);
5075 this->set_file_offset(os->offset() + offset);
5077 this->set_current_data_size(this->original_size_);
5078 this->finalize_data_size();
5081 template<bool big_endian>
5083 Arm_input_section<big_endian>::do_write(Output_file* of)
5085 // We have to write out the original section content.
5086 section_size_type section_size;
5087 const unsigned char* section_contents =
5088 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5089 of->write(this->offset(), section_contents, section_size);
5091 // If this owns a stub table and it is not empty, write it.
5092 if (this->is_stub_table_owner() && !this->stub_table_->empty())
5093 this->stub_table_->write(of);
5096 // Finalize data size.
5098 template<bool big_endian>
5100 Arm_input_section<big_endian>::set_final_data_size()
5102 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5104 if (this->is_stub_table_owner())
5106 this->stub_table_->finalize_data_size();
5107 off = align_address(off, this->stub_table_->addralign());
5108 off += this->stub_table_->data_size();
5110 this->set_data_size(off);
5113 // Reset address and file offset.
5115 template<bool big_endian>
5117 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
5119 // Size of the original input section contents.
5120 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5122 // If this is a stub table owner, account for the stub table size.
5123 if (this->is_stub_table_owner())
5125 Stub_table<big_endian>* stub_table = this->stub_table_;
5127 // Reset the stub table's address and file offset. The
5128 // current data size for child will be updated after that.
5129 stub_table_->reset_address_and_file_offset();
5130 off = align_address(off, stub_table_->addralign());
5131 off += stub_table->current_data_size();
5134 this->set_current_data_size(off);
5137 // Arm_exidx_cantunwind methods.
5139 // Write this to Output file OF for a fixed endianness.
5141 template<bool big_endian>
5143 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
5145 off_t offset = this->offset();
5146 const section_size_type oview_size = 8;
5147 unsigned char* const oview = of->get_output_view(offset, oview_size);
5149 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5150 Valtype* wv = reinterpret_cast<Valtype*>(oview);
5152 Output_section* os = this->relobj_->output_section(this->shndx_);
5153 gold_assert(os != NULL);
5155 Arm_relobj<big_endian>* arm_relobj =
5156 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
5157 Arm_address output_offset =
5158 arm_relobj->get_output_section_offset(this->shndx_);
5159 Arm_address section_start;
5160 if (output_offset != Arm_relobj<big_endian>::invalid_address)
5161 section_start = os->address() + output_offset;
5164 // Currently this only happens for a relaxed section.
5165 const Output_relaxed_input_section* poris =
5166 os->find_relaxed_input_section(this->relobj_, this->shndx_);
5167 gold_assert(poris != NULL);
5168 section_start = poris->address();
5171 // We always append this to the end of an EXIDX section.
5172 Arm_address output_address =
5173 section_start + this->relobj_->section_size(this->shndx_);
5175 // Write out the entry. The first word either points to the beginning
5176 // or after the end of a text section. The second word is the special
5177 // EXIDX_CANTUNWIND value.
5178 uint32_t prel31_offset = output_address - this->address();
5179 if (utils::has_overflow<31>(offset))
5180 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
5181 elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
5182 elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
5184 of->write_output_view(this->offset(), oview_size, oview);
5187 // Arm_exidx_merged_section methods.
5189 // Constructor for Arm_exidx_merged_section.
5190 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5191 // SECTION_OFFSET_MAP points to a section offset map describing how
5192 // parts of the input section are mapped to output. DELETED_BYTES is
5193 // the number of bytes deleted from the EXIDX input section.
5195 Arm_exidx_merged_section::Arm_exidx_merged_section(
5196 const Arm_exidx_input_section& exidx_input_section,
5197 const Arm_exidx_section_offset_map& section_offset_map,
5198 uint32_t deleted_bytes)
5199 : Output_relaxed_input_section(exidx_input_section.relobj(),
5200 exidx_input_section.shndx(),
5201 exidx_input_section.addralign()),
5202 exidx_input_section_(exidx_input_section),
5203 section_offset_map_(section_offset_map)
5205 // Fix size here so that we do not need to implement set_final_data_size.
5206 this->set_data_size(exidx_input_section.size() - deleted_bytes);
5207 this->fix_data_size();
5210 // Given an input OBJECT, an input section index SHNDX within that
5211 // object, and an OFFSET relative to the start of that input
5212 // section, return whether or not the corresponding offset within
5213 // the output section is known. If this function returns true, it
5214 // sets *POUTPUT to the output offset. The value -1 indicates that
5215 // this input offset is being discarded.
5218 Arm_exidx_merged_section::do_output_offset(
5219 const Relobj* relobj,
5221 section_offset_type offset,
5222 section_offset_type* poutput) const
5224 // We only handle offsets for the original EXIDX input section.
5225 if (relobj != this->exidx_input_section_.relobj()
5226 || shndx != this->exidx_input_section_.shndx())
5229 section_offset_type section_size =
5230 convert_types<section_offset_type>(this->exidx_input_section_.size());
5231 if (offset < 0 || offset >= section_size)
5232 // Input offset is out of valid range.
5236 // We need to look up the section offset map to determine the output
5237 // offset. Find the reference point in map that is first offset
5238 // bigger than or equal to this offset.
5239 Arm_exidx_section_offset_map::const_iterator p =
5240 this->section_offset_map_.lower_bound(offset);
5242 // The section offset maps are build such that this should not happen if
5243 // input offset is in the valid range.
5244 gold_assert(p != this->section_offset_map_.end());
5246 // We need to check if this is dropped.
5247 section_offset_type ref = p->first;
5248 section_offset_type mapped_ref = p->second;
5250 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5251 // Offset is present in output.
5252 *poutput = mapped_ref + (offset - ref);
5254 // Offset is discarded owing to EXIDX entry merging.
5261 // Write this to output file OF.
5264 Arm_exidx_merged_section::do_write(Output_file* of)
5266 // If we retain or discard the whole EXIDX input section, we would
5268 gold_assert(this->data_size() != this->exidx_input_section_.size()
5269 && this->data_size() != 0);
5271 off_t offset = this->offset();
5272 const section_size_type oview_size = this->data_size();
5273 unsigned char* const oview = of->get_output_view(offset, oview_size);
5275 Output_section* os = this->relobj()->output_section(this->shndx());
5276 gold_assert(os != NULL);
5278 // Get contents of EXIDX input section.
5279 section_size_type section_size;
5280 const unsigned char* section_contents =
5281 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5282 gold_assert(section_size == this->exidx_input_section_.size());
5284 // Go over spans of input offsets and write only those that are not
5286 section_offset_type in_start = 0;
5287 section_offset_type out_start = 0;
5288 for(Arm_exidx_section_offset_map::const_iterator p =
5289 this->section_offset_map_.begin();
5290 p != this->section_offset_map_.end();
5293 section_offset_type in_end = p->first;
5294 gold_assert(in_end >= in_start);
5295 section_offset_type out_end = p->second;
5296 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5299 size_t out_chunk_size =
5300 convert_types<size_t>(out_end - out_start + 1);
5301 gold_assert(out_chunk_size == in_chunk_size);
5302 memcpy(oview + out_start, section_contents + in_start,
5304 out_start += out_chunk_size;
5306 in_start += in_chunk_size;
5309 gold_assert(convert_to_section_size_type(out_start) == oview_size);
5310 of->write_output_view(this->offset(), oview_size, oview);
5313 // Arm_exidx_fixup methods.
5315 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5316 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5317 // points to the end of the last seen EXIDX section.
5320 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5322 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5323 && this->last_input_section_ != NULL)
5325 Relobj* relobj = this->last_input_section_->relobj();
5326 unsigned int text_shndx = this->last_input_section_->link();
5327 Arm_exidx_cantunwind* cantunwind =
5328 new Arm_exidx_cantunwind(relobj, text_shndx);
5329 this->exidx_output_section_->add_output_section_data(cantunwind);
5330 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5334 // Process an EXIDX section entry in input. Return whether this entry
5335 // can be deleted in the output. SECOND_WORD in the second word of the
5339 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5342 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5344 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5345 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5346 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5348 else if ((second_word & 0x80000000) != 0)
5350 // Inlined unwinding data. Merge if equal to previous.
5351 delete_entry = (merge_exidx_entries_
5352 && this->last_unwind_type_ == UT_INLINED_ENTRY
5353 && this->last_inlined_entry_ == second_word);
5354 this->last_unwind_type_ = UT_INLINED_ENTRY;
5355 this->last_inlined_entry_ = second_word;
5359 // Normal table entry. In theory we could merge these too,
5360 // but duplicate entries are likely to be much less common.
5361 delete_entry = false;
5362 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5364 return delete_entry;
5367 // Update the current section offset map during EXIDX section fix-up.
5368 // If there is no map, create one. INPUT_OFFSET is the offset of a
5369 // reference point, DELETED_BYTES is the number of deleted by in the
5370 // section so far. If DELETE_ENTRY is true, the reference point and
5371 // all offsets after the previous reference point are discarded.
5374 Arm_exidx_fixup::update_offset_map(
5375 section_offset_type input_offset,
5376 section_size_type deleted_bytes,
5379 if (this->section_offset_map_ == NULL)
5380 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5381 section_offset_type output_offset;
5383 output_offset = Arm_exidx_input_section::invalid_offset;
5385 output_offset = input_offset - deleted_bytes;
5386 (*this->section_offset_map_)[input_offset] = output_offset;
5389 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5390 // bytes deleted. If some entries are merged, also store a pointer to a newly
5391 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5392 // caller owns the map and is responsible for releasing it after use.
5394 template<bool big_endian>
5396 Arm_exidx_fixup::process_exidx_section(
5397 const Arm_exidx_input_section* exidx_input_section,
5398 Arm_exidx_section_offset_map** psection_offset_map)
5400 Relobj* relobj = exidx_input_section->relobj();
5401 unsigned shndx = exidx_input_section->shndx();
5402 section_size_type section_size;
5403 const unsigned char* section_contents =
5404 relobj->section_contents(shndx, §ion_size, false);
5406 if ((section_size % 8) != 0)
5408 // Something is wrong with this section. Better not touch it.
5409 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5410 relobj->name().c_str(), shndx);
5411 this->last_input_section_ = exidx_input_section;
5412 this->last_unwind_type_ = UT_NONE;
5416 uint32_t deleted_bytes = 0;
5417 bool prev_delete_entry = false;
5418 gold_assert(this->section_offset_map_ == NULL);
5420 for (section_size_type i = 0; i < section_size; i += 8)
5422 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5424 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5425 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5427 bool delete_entry = this->process_exidx_entry(second_word);
5429 // Entry deletion causes changes in output offsets. We use a std::map
5430 // to record these. And entry (x, y) means input offset x
5431 // is mapped to output offset y. If y is invalid_offset, then x is
5432 // dropped in the output. Because of the way std::map::lower_bound
5433 // works, we record the last offset in a region w.r.t to keeping or
5434 // dropping. If there is no entry (x0, y0) for an input offset x0,
5435 // the output offset y0 of it is determined by the output offset y1 of
5436 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5437 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5439 if (delete_entry != prev_delete_entry && i != 0)
5440 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5442 // Update total deleted bytes for this entry.
5446 prev_delete_entry = delete_entry;
5449 // If section offset map is not NULL, make an entry for the end of
5451 if (this->section_offset_map_ != NULL)
5452 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5454 *psection_offset_map = this->section_offset_map_;
5455 this->section_offset_map_ = NULL;
5456 this->last_input_section_ = exidx_input_section;
5458 // Set the first output text section so that we can link the EXIDX output
5459 // section to it. Ignore any EXIDX input section that is completely merged.
5460 if (this->first_output_text_section_ == NULL
5461 && deleted_bytes != section_size)
5463 unsigned int link = exidx_input_section->link();
5464 Output_section* os = relobj->output_section(link);
5465 gold_assert(os != NULL);
5466 this->first_output_text_section_ = os;
5469 return deleted_bytes;
5472 // Arm_output_section methods.
5474 // Create a stub group for input sections from BEGIN to END. OWNER
5475 // points to the input section to be the owner a new stub table.
5477 template<bool big_endian>
5479 Arm_output_section<big_endian>::create_stub_group(
5480 Input_section_list::const_iterator begin,
5481 Input_section_list::const_iterator end,
5482 Input_section_list::const_iterator owner,
5483 Target_arm<big_endian>* target,
5484 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
5486 // We use a different kind of relaxed section in an EXIDX section.
5487 // The static casting from Output_relaxed_input_section to
5488 // Arm_input_section is invalid in an EXIDX section. We are okay
5489 // because we should not be calling this for an EXIDX section.
5490 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5492 // Currently we convert ordinary input sections into relaxed sections only
5493 // at this point but we may want to support creating relaxed input section
5494 // very early. So we check here to see if owner is already a relaxed
5497 Arm_input_section<big_endian>* arm_input_section;
5498 if (owner->is_relaxed_input_section())
5501 Arm_input_section<big_endian>::as_arm_input_section(
5502 owner->relaxed_input_section());
5506 gold_assert(owner->is_input_section());
5507 // Create a new relaxed input section.
5509 target->new_arm_input_section(owner->relobj(), owner->shndx());
5510 new_relaxed_sections->push_back(arm_input_section);
5513 // Create a stub table.
5514 Stub_table<big_endian>* stub_table =
5515 target->new_stub_table(arm_input_section);
5517 arm_input_section->set_stub_table(stub_table);
5519 Input_section_list::const_iterator p = begin;
5520 Input_section_list::const_iterator prev_p;
5522 // Look for input sections or relaxed input sections in [begin ... end].
5525 if (p->is_input_section() || p->is_relaxed_input_section())
5527 // The stub table information for input sections live
5528 // in their objects.
5529 Arm_relobj<big_endian>* arm_relobj =
5530 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5531 arm_relobj->set_stub_table(p->shndx(), stub_table);
5535 while (prev_p != end);
5538 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5539 // of stub groups. We grow a stub group by adding input section until the
5540 // size is just below GROUP_SIZE. The last input section will be converted
5541 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5542 // input section after the stub table, effectively double the group size.
5544 // This is similar to the group_sections() function in elf32-arm.c but is
5545 // implemented differently.
5547 template<bool big_endian>
5549 Arm_output_section<big_endian>::group_sections(
5550 section_size_type group_size,
5551 bool stubs_always_after_branch,
5552 Target_arm<big_endian>* target)
5554 // We only care about sections containing code.
5555 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5558 // States for grouping.
5561 // No group is being built.
5563 // A group is being built but the stub table is not found yet.
5564 // We keep group a stub group until the size is just under GROUP_SIZE.
5565 // The last input section in the group will be used as the stub table.
5566 FINDING_STUB_SECTION,
5567 // A group is being built and we have already found a stub table.
5568 // We enter this state to grow a stub group by adding input section
5569 // after the stub table. This effectively doubles the group size.
5573 // Any newly created relaxed sections are stored here.
5574 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5576 State state = NO_GROUP;
5577 section_size_type off = 0;
5578 section_size_type group_begin_offset = 0;
5579 section_size_type group_end_offset = 0;
5580 section_size_type stub_table_end_offset = 0;
5581 Input_section_list::const_iterator group_begin =
5582 this->input_sections().end();
5583 Input_section_list::const_iterator stub_table =
5584 this->input_sections().end();
5585 Input_section_list::const_iterator group_end = this->input_sections().end();
5586 for (Input_section_list::const_iterator p = this->input_sections().begin();
5587 p != this->input_sections().end();
5590 section_size_type section_begin_offset =
5591 align_address(off, p->addralign());
5592 section_size_type section_end_offset =
5593 section_begin_offset + p->data_size();
5595 // Check to see if we should group the previously seens sections.
5601 case FINDING_STUB_SECTION:
5602 // Adding this section makes the group larger than GROUP_SIZE.
5603 if (section_end_offset - group_begin_offset >= group_size)
5605 if (stubs_always_after_branch)
5607 gold_assert(group_end != this->input_sections().end());
5608 this->create_stub_group(group_begin, group_end, group_end,
5609 target, &new_relaxed_sections);
5614 // But wait, there's more! Input sections up to
5615 // stub_group_size bytes after the stub table can be
5616 // handled by it too.
5617 state = HAS_STUB_SECTION;
5618 stub_table = group_end;
5619 stub_table_end_offset = group_end_offset;
5624 case HAS_STUB_SECTION:
5625 // Adding this section makes the post stub-section group larger
5627 if (section_end_offset - stub_table_end_offset >= group_size)
5629 gold_assert(group_end != this->input_sections().end());
5630 this->create_stub_group(group_begin, group_end, stub_table,
5631 target, &new_relaxed_sections);
5640 // If we see an input section and currently there is no group, start
5641 // a new one. Skip any empty sections.
5642 if ((p->is_input_section() || p->is_relaxed_input_section())
5643 && (p->relobj()->section_size(p->shndx()) != 0))
5645 if (state == NO_GROUP)
5647 state = FINDING_STUB_SECTION;
5649 group_begin_offset = section_begin_offset;
5652 // Keep track of the last input section seen.
5654 group_end_offset = section_end_offset;
5657 off = section_end_offset;
5660 // Create a stub group for any ungrouped sections.
5661 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5663 gold_assert(group_end != this->input_sections().end());
5664 this->create_stub_group(group_begin, group_end,
5665 (state == FINDING_STUB_SECTION
5668 target, &new_relaxed_sections);
5671 // Convert input section into relaxed input section in a batch.
5672 if (!new_relaxed_sections.empty())
5673 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5675 // Update the section offsets
5676 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5678 Arm_relobj<big_endian>* arm_relobj =
5679 Arm_relobj<big_endian>::as_arm_relobj(
5680 new_relaxed_sections[i]->relobj());
5681 unsigned int shndx = new_relaxed_sections[i]->shndx();
5682 // Tell Arm_relobj that this input section is converted.
5683 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5687 // Append non empty text sections in this to LIST in ascending
5688 // order of their position in this.
5690 template<bool big_endian>
5692 Arm_output_section<big_endian>::append_text_sections_to_list(
5693 Text_section_list* list)
5695 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5697 for (Input_section_list::const_iterator p = this->input_sections().begin();
5698 p != this->input_sections().end();
5701 // We only care about plain or relaxed input sections. We also
5702 // ignore any merged sections.
5703 if ((p->is_input_section() || p->is_relaxed_input_section())
5704 && p->data_size() != 0)
5705 list->push_back(Text_section_list::value_type(p->relobj(),
5710 template<bool big_endian>
5712 Arm_output_section<big_endian>::fix_exidx_coverage(
5714 const Text_section_list& sorted_text_sections,
5715 Symbol_table* symtab,
5716 bool merge_exidx_entries)
5718 // We should only do this for the EXIDX output section.
5719 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5721 // We don't want the relaxation loop to undo these changes, so we discard
5722 // the current saved states and take another one after the fix-up.
5723 this->discard_states();
5725 // Remove all input sections.
5726 uint64_t address = this->address();
5727 typedef std::list<Output_section::Input_section> Input_section_list;
5728 Input_section_list input_sections;
5729 this->reset_address_and_file_offset();
5730 this->get_input_sections(address, std::string(""), &input_sections);
5732 if (!this->input_sections().empty())
5733 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5735 // Go through all the known input sections and record them.
5736 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5737 typedef Unordered_map<Section_id, const Output_section::Input_section*,
5738 Section_id_hash> Text_to_exidx_map;
5739 Text_to_exidx_map text_to_exidx_map;
5740 for (Input_section_list::const_iterator p = input_sections.begin();
5741 p != input_sections.end();
5744 // This should never happen. At this point, we should only see
5745 // plain EXIDX input sections.
5746 gold_assert(!p->is_relaxed_input_section());
5747 text_to_exidx_map[Section_id(p->relobj(), p->shndx())] = &(*p);
5750 Arm_exidx_fixup exidx_fixup(this, merge_exidx_entries);
5752 // Go over the sorted text sections.
5753 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5754 Section_id_set processed_input_sections;
5755 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5756 p != sorted_text_sections.end();
5759 Relobj* relobj = p->first;
5760 unsigned int shndx = p->second;
5762 Arm_relobj<big_endian>* arm_relobj =
5763 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5764 const Arm_exidx_input_section* exidx_input_section =
5765 arm_relobj->exidx_input_section_by_link(shndx);
5767 // If this text section has no EXIDX section or if the EXIDX section
5768 // has errors, force an EXIDX_CANTUNWIND entry pointing to the end
5769 // of the last seen EXIDX section.
5770 if (exidx_input_section == NULL || exidx_input_section->has_errors())
5772 exidx_fixup.add_exidx_cantunwind_as_needed();
5776 Relobj* exidx_relobj = exidx_input_section->relobj();
5777 unsigned int exidx_shndx = exidx_input_section->shndx();
5778 Section_id sid(exidx_relobj, exidx_shndx);
5779 Text_to_exidx_map::const_iterator iter = text_to_exidx_map.find(sid);
5780 if (iter == text_to_exidx_map.end())
5782 // This is odd. We have not seen this EXIDX input section before.
5783 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5784 // issue a warning instead. We assume the user knows what he
5785 // or she is doing. Otherwise, this is an error.
5786 if (layout->script_options()->saw_sections_clause())
5787 gold_warning(_("unwinding may not work because EXIDX input section"
5788 " %u of %s is not in EXIDX output section"),
5789 exidx_shndx, exidx_relobj->name().c_str());
5791 gold_error(_("unwinding may not work because EXIDX input section"
5792 " %u of %s is not in EXIDX output section"),
5793 exidx_shndx, exidx_relobj->name().c_str());
5795 exidx_fixup.add_exidx_cantunwind_as_needed();
5799 // Fix up coverage and append input section to output data list.
5800 Arm_exidx_section_offset_map* section_offset_map = NULL;
5801 uint32_t deleted_bytes =
5802 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5803 §ion_offset_map);
5805 if (deleted_bytes == exidx_input_section->size())
5807 // The whole EXIDX section got merged. Remove it from output.
5808 gold_assert(section_offset_map == NULL);
5809 exidx_relobj->set_output_section(exidx_shndx, NULL);
5811 // All local symbols defined in this input section will be dropped.
5812 // We need to adjust output local symbol count.
5813 arm_relobj->set_output_local_symbol_count_needs_update();
5815 else if (deleted_bytes > 0)
5817 // Some entries are merged. We need to convert this EXIDX input
5818 // section into a relaxed section.
5819 gold_assert(section_offset_map != NULL);
5820 Arm_exidx_merged_section* merged_section =
5821 new Arm_exidx_merged_section(*exidx_input_section,
5822 *section_offset_map, deleted_bytes);
5823 this->add_relaxed_input_section(merged_section);
5824 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5826 // All local symbols defined in discarded portions of this input
5827 // section will be dropped. We need to adjust output local symbol
5829 arm_relobj->set_output_local_symbol_count_needs_update();
5833 // Just add back the EXIDX input section.
5834 gold_assert(section_offset_map == NULL);
5835 const Output_section::Input_section* pis = iter->second;
5836 gold_assert(pis->is_input_section());
5837 this->add_script_input_section(*pis);
5840 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5843 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5844 exidx_fixup.add_exidx_cantunwind_as_needed();
5846 // Remove any known EXIDX input sections that are not processed.
5847 for (Input_section_list::const_iterator p = input_sections.begin();
5848 p != input_sections.end();
5851 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5852 == processed_input_sections.end())
5854 // We discard a known EXIDX section because its linked
5855 // text section has been folded by ICF. We also discard an
5856 // EXIDX section with error, the output does not matter in this
5857 // case. We do this to avoid triggering asserts.
5858 Arm_relobj<big_endian>* arm_relobj =
5859 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5860 const Arm_exidx_input_section* exidx_input_section =
5861 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5862 gold_assert(exidx_input_section != NULL);
5863 if (!exidx_input_section->has_errors())
5865 unsigned int text_shndx = exidx_input_section->link();
5866 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5869 // Remove this from link. We also need to recount the
5871 p->relobj()->set_output_section(p->shndx(), NULL);
5872 arm_relobj->set_output_local_symbol_count_needs_update();
5876 // Link exidx output section to the first seen output section and
5877 // set correct entry size.
5878 this->set_link_section(exidx_fixup.first_output_text_section());
5879 this->set_entsize(8);
5881 // Make changes permanent.
5882 this->save_states();
5883 this->set_section_offsets_need_adjustment();
5886 // Link EXIDX output sections to text output sections.
5888 template<bool big_endian>
5890 Arm_output_section<big_endian>::set_exidx_section_link()
5892 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5893 if (!this->input_sections().empty())
5895 Input_section_list::const_iterator p = this->input_sections().begin();
5896 Arm_relobj<big_endian>* arm_relobj =
5897 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5898 unsigned exidx_shndx = p->shndx();
5899 const Arm_exidx_input_section* exidx_input_section =
5900 arm_relobj->exidx_input_section_by_shndx(exidx_shndx);
5901 gold_assert(exidx_input_section != NULL);
5902 unsigned int text_shndx = exidx_input_section->link();
5903 Output_section* os = arm_relobj->output_section(text_shndx);
5904 this->set_link_section(os);
5908 // Arm_relobj methods.
5910 // Determine if an input section is scannable for stub processing. SHDR is
5911 // the header of the section and SHNDX is the section index. OS is the output
5912 // section for the input section and SYMTAB is the global symbol table used to
5913 // look up ICF information.
5915 template<bool big_endian>
5917 Arm_relobj<big_endian>::section_is_scannable(
5918 const elfcpp::Shdr<32, big_endian>& shdr,
5920 const Output_section* os,
5921 const Symbol_table *symtab)
5923 // Skip any empty sections, unallocated sections or sections whose
5924 // type are not SHT_PROGBITS.
5925 if (shdr.get_sh_size() == 0
5926 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
5927 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
5930 // Skip any discarded or ICF'ed sections.
5931 if (os == NULL || symtab->is_section_folded(this, shndx))
5934 // If this requires special offset handling, check to see if it is
5935 // a relaxed section. If this is not, then it is a merged section that
5936 // we cannot handle.
5937 if (this->is_output_section_offset_invalid(shndx))
5939 const Output_relaxed_input_section* poris =
5940 os->find_relaxed_input_section(this, shndx);
5948 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5949 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5951 template<bool big_endian>
5953 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
5954 const elfcpp::Shdr<32, big_endian>& shdr,
5955 const Relobj::Output_sections& out_sections,
5956 const Symbol_table *symtab,
5957 const unsigned char* pshdrs)
5959 unsigned int sh_type = shdr.get_sh_type();
5960 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
5963 // Ignore empty section.
5964 off_t sh_size = shdr.get_sh_size();
5968 // Ignore reloc section with unexpected symbol table. The
5969 // error will be reported in the final link.
5970 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
5973 unsigned int reloc_size;
5974 if (sh_type == elfcpp::SHT_REL)
5975 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5977 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5979 // Ignore reloc section with unexpected entsize or uneven size.
5980 // The error will be reported in the final link.
5981 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
5984 // Ignore reloc section with bad info. This error will be
5985 // reported in the final link.
5986 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5987 if (index >= this->shnum())
5990 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5991 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
5992 return this->section_is_scannable(text_shdr, index,
5993 out_sections[index], symtab);
5996 // Return the output address of either a plain input section or a relaxed
5997 // input section. SHNDX is the section index. We define and use this
5998 // instead of calling Output_section::output_address because that is slow
5999 // for large output.
6001 template<bool big_endian>
6003 Arm_relobj<big_endian>::simple_input_section_output_address(
6007 if (this->is_output_section_offset_invalid(shndx))
6009 const Output_relaxed_input_section* poris =
6010 os->find_relaxed_input_section(this, shndx);
6011 // We do not handle merged sections here.
6012 gold_assert(poris != NULL);
6013 return poris->address();
6016 return os->address() + this->get_output_section_offset(shndx);
6019 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
6020 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
6022 template<bool big_endian>
6024 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
6025 const elfcpp::Shdr<32, big_endian>& shdr,
6028 const Symbol_table* symtab)
6030 if (!this->section_is_scannable(shdr, shndx, os, symtab))
6033 // If the section does not cross any 4K-boundaries, it does not need to
6035 Arm_address address = this->simple_input_section_output_address(shndx, os);
6036 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
6042 // Scan a section for Cortex-A8 workaround.
6044 template<bool big_endian>
6046 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
6047 const elfcpp::Shdr<32, big_endian>& shdr,
6050 Target_arm<big_endian>* arm_target)
6052 // Look for the first mapping symbol in this section. It should be
6054 Mapping_symbol_position section_start(shndx, 0);
6055 typename Mapping_symbols_info::const_iterator p =
6056 this->mapping_symbols_info_.lower_bound(section_start);
6058 // There are no mapping symbols for this section. Treat it as a data-only
6059 // section. Issue a warning if section is marked as containing
6061 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
6063 if ((this->section_flags(shndx) & elfcpp::SHF_EXECINSTR) != 0)
6064 gold_warning(_("cannot scan executable section %u of %s for Cortex-A8 "
6065 "erratum because it has no mapping symbols."),
6066 shndx, this->name().c_str());
6070 Arm_address output_address =
6071 this->simple_input_section_output_address(shndx, os);
6073 // Get the section contents.
6074 section_size_type input_view_size = 0;
6075 const unsigned char* input_view =
6076 this->section_contents(shndx, &input_view_size, false);
6078 // We need to go through the mapping symbols to determine what to
6079 // scan. There are two reasons. First, we should look at THUMB code and
6080 // THUMB code only. Second, we only want to look at the 4K-page boundary
6081 // to speed up the scanning.
6083 while (p != this->mapping_symbols_info_.end()
6084 && p->first.first == shndx)
6086 typename Mapping_symbols_info::const_iterator next =
6087 this->mapping_symbols_info_.upper_bound(p->first);
6089 // Only scan part of a section with THUMB code.
6090 if (p->second == 't')
6092 // Determine the end of this range.
6093 section_size_type span_start =
6094 convert_to_section_size_type(p->first.second);
6095 section_size_type span_end;
6096 if (next != this->mapping_symbols_info_.end()
6097 && next->first.first == shndx)
6098 span_end = convert_to_section_size_type(next->first.second);
6100 span_end = convert_to_section_size_type(shdr.get_sh_size());
6102 if (((span_start + output_address) & ~0xfffUL)
6103 != ((span_end + output_address - 1) & ~0xfffUL))
6105 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
6106 span_start, span_end,
6116 // Scan relocations for stub generation.
6118 template<bool big_endian>
6120 Arm_relobj<big_endian>::scan_sections_for_stubs(
6121 Target_arm<big_endian>* arm_target,
6122 const Symbol_table* symtab,
6123 const Layout* layout)
6125 unsigned int shnum = this->shnum();
6126 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6128 // Read the section headers.
6129 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6133 // To speed up processing, we set up hash tables for fast lookup of
6134 // input offsets to output addresses.
6135 this->initialize_input_to_output_maps();
6137 const Relobj::Output_sections& out_sections(this->output_sections());
6139 Relocate_info<32, big_endian> relinfo;
6140 relinfo.symtab = symtab;
6141 relinfo.layout = layout;
6142 relinfo.object = this;
6144 // Do relocation stubs scanning.
6145 const unsigned char* p = pshdrs + shdr_size;
6146 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6148 const elfcpp::Shdr<32, big_endian> shdr(p);
6149 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
6152 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
6153 Arm_address output_offset = this->get_output_section_offset(index);
6154 Arm_address output_address;
6155 if (output_offset != invalid_address)
6156 output_address = out_sections[index]->address() + output_offset;
6159 // Currently this only happens for a relaxed section.
6160 const Output_relaxed_input_section* poris =
6161 out_sections[index]->find_relaxed_input_section(this, index);
6162 gold_assert(poris != NULL);
6163 output_address = poris->address();
6166 // Get the relocations.
6167 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
6171 // Get the section contents. This does work for the case in which
6172 // we modify the contents of an input section. We need to pass the
6173 // output view under such circumstances.
6174 section_size_type input_view_size = 0;
6175 const unsigned char* input_view =
6176 this->section_contents(index, &input_view_size, false);
6178 relinfo.reloc_shndx = i;
6179 relinfo.data_shndx = index;
6180 unsigned int sh_type = shdr.get_sh_type();
6181 unsigned int reloc_size;
6182 if (sh_type == elfcpp::SHT_REL)
6183 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6185 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6187 Output_section* os = out_sections[index];
6188 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
6189 shdr.get_sh_size() / reloc_size,
6191 output_offset == invalid_address,
6192 input_view, output_address,
6197 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
6198 // after its relocation section, if there is one, is processed for
6199 // relocation stubs. Merging this loop with the one above would have been
6200 // complicated since we would have had to make sure that relocation stub
6201 // scanning is done first.
6202 if (arm_target->fix_cortex_a8())
6204 const unsigned char* p = pshdrs + shdr_size;
6205 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6207 const elfcpp::Shdr<32, big_endian> shdr(p);
6208 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
6211 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
6216 // After we've done the relocations, we release the hash tables,
6217 // since we no longer need them.
6218 this->free_input_to_output_maps();
6221 // Count the local symbols. The ARM backend needs to know if a symbol
6222 // is a THUMB function or not. For global symbols, it is easy because
6223 // the Symbol object keeps the ELF symbol type. For local symbol it is
6224 // harder because we cannot access this information. So we override the
6225 // do_count_local_symbol in parent and scan local symbols to mark
6226 // THUMB functions. This is not the most efficient way but I do not want to
6227 // slow down other ports by calling a per symbol targer hook inside
6228 // Sized_relobj<size, big_endian>::do_count_local_symbols.
6230 template<bool big_endian>
6232 Arm_relobj<big_endian>::do_count_local_symbols(
6233 Stringpool_template<char>* pool,
6234 Stringpool_template<char>* dynpool)
6236 // We need to fix-up the values of any local symbols whose type are
6239 // Ask parent to count the local symbols.
6240 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
6241 const unsigned int loccount = this->local_symbol_count();
6245 // Intialize the thumb function bit-vector.
6246 std::vector<bool> empty_vector(loccount, false);
6247 this->local_symbol_is_thumb_function_.swap(empty_vector);
6249 // Read the symbol table section header.
6250 const unsigned int symtab_shndx = this->symtab_shndx();
6251 elfcpp::Shdr<32, big_endian>
6252 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6253 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6255 // Read the local symbols.
6256 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6257 gold_assert(loccount == symtabshdr.get_sh_info());
6258 off_t locsize = loccount * sym_size;
6259 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6260 locsize, true, true);
6262 // For mapping symbol processing, we need to read the symbol names.
6263 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6264 if (strtab_shndx >= this->shnum())
6266 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6270 elfcpp::Shdr<32, big_endian>
6271 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6272 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6274 this->error(_("symbol table name section has wrong type: %u"),
6275 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6278 const char* pnames =
6279 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6280 strtabshdr.get_sh_size(),
6283 // Loop over the local symbols and mark any local symbols pointing
6284 // to THUMB functions.
6286 // Skip the first dummy symbol.
6288 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
6289 this->local_values();
6290 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6292 elfcpp::Sym<32, big_endian> sym(psyms);
6293 elfcpp::STT st_type = sym.get_st_type();
6294 Symbol_value<32>& lv((*plocal_values)[i]);
6295 Arm_address input_value = lv.input_value();
6297 // Check to see if this is a mapping symbol.
6298 const char* sym_name = pnames + sym.get_st_name();
6299 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6302 unsigned int input_shndx =
6303 this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
6304 gold_assert(is_ordinary);
6306 // Strip of LSB in case this is a THUMB symbol.
6307 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6308 this->mapping_symbols_info_[msp] = sym_name[1];
6311 if (st_type == elfcpp::STT_ARM_TFUNC
6312 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6314 // This is a THUMB function. Mark this and canonicalize the
6315 // symbol value by setting LSB.
6316 this->local_symbol_is_thumb_function_[i] = true;
6317 if ((input_value & 1) == 0)
6318 lv.set_input_value(input_value | 1);
6323 // Relocate sections.
6324 template<bool big_endian>
6326 Arm_relobj<big_endian>::do_relocate_sections(
6327 const Symbol_table* symtab,
6328 const Layout* layout,
6329 const unsigned char* pshdrs,
6330 typename Sized_relobj<32, big_endian>::Views* pviews)
6332 // Call parent to relocate sections.
6333 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
6336 // We do not generate stubs if doing a relocatable link.
6337 if (parameters->options().relocatable())
6340 // Relocate stub tables.
6341 unsigned int shnum = this->shnum();
6343 Target_arm<big_endian>* arm_target =
6344 Target_arm<big_endian>::default_target();
6346 Relocate_info<32, big_endian> relinfo;
6347 relinfo.symtab = symtab;
6348 relinfo.layout = layout;
6349 relinfo.object = this;
6351 for (unsigned int i = 1; i < shnum; ++i)
6353 Arm_input_section<big_endian>* arm_input_section =
6354 arm_target->find_arm_input_section(this, i);
6356 if (arm_input_section != NULL
6357 && arm_input_section->is_stub_table_owner()
6358 && !arm_input_section->stub_table()->empty())
6360 // We cannot discard a section if it owns a stub table.
6361 Output_section* os = this->output_section(i);
6362 gold_assert(os != NULL);
6364 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6365 relinfo.reloc_shdr = NULL;
6366 relinfo.data_shndx = i;
6367 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6369 gold_assert((*pviews)[i].view != NULL);
6371 // We are passed the output section view. Adjust it to cover the
6373 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6374 gold_assert((stub_table->address() >= (*pviews)[i].address)
6375 && ((stub_table->address() + stub_table->data_size())
6376 <= (*pviews)[i].address + (*pviews)[i].view_size));
6378 off_t offset = stub_table->address() - (*pviews)[i].address;
6379 unsigned char* view = (*pviews)[i].view + offset;
6380 Arm_address address = stub_table->address();
6381 section_size_type view_size = stub_table->data_size();
6383 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6387 // Apply Cortex A8 workaround if applicable.
6388 if (this->section_has_cortex_a8_workaround(i))
6390 unsigned char* view = (*pviews)[i].view;
6391 Arm_address view_address = (*pviews)[i].address;
6392 section_size_type view_size = (*pviews)[i].view_size;
6393 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6395 // Adjust view to cover section.
6396 Output_section* os = this->output_section(i);
6397 gold_assert(os != NULL);
6398 Arm_address section_address =
6399 this->simple_input_section_output_address(i, os);
6400 uint64_t section_size = this->section_size(i);
6402 gold_assert(section_address >= view_address
6403 && ((section_address + section_size)
6404 <= (view_address + view_size)));
6406 unsigned char* section_view = view + (section_address - view_address);
6408 // Apply the Cortex-A8 workaround to the output address range
6409 // corresponding to this input section.
6410 stub_table->apply_cortex_a8_workaround_to_address_range(
6419 // Find the linked text section of an EXIDX section by looking the the first
6420 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6421 // must be linked to to its associated code section via the sh_link field of
6422 // its section header. However, some tools are broken and the link is not
6423 // always set. LD just drops such an EXIDX section silently, causing the
6424 // associated code not unwindabled. Here we try a little bit harder to
6425 // discover the linked code section.
6427 // PSHDR points to the section header of a relocation section of an EXIDX
6428 // section. If we can find a linked text section, return true and
6429 // store the text section index in the location PSHNDX. Otherwise
6432 template<bool big_endian>
6434 Arm_relobj<big_endian>::find_linked_text_section(
6435 const unsigned char* pshdr,
6436 const unsigned char* psyms,
6437 unsigned int* pshndx)
6439 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6441 // If there is no relocation, we cannot find the linked text section.
6443 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6444 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6446 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6447 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6449 // Get the relocations.
6450 const unsigned char* prelocs =
6451 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6453 // Find the REL31 relocation for the first word of the first EXIDX entry.
6454 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6456 Arm_address r_offset;
6457 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6458 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6460 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6461 r_info = reloc.get_r_info();
6462 r_offset = reloc.get_r_offset();
6466 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6467 r_info = reloc.get_r_info();
6468 r_offset = reloc.get_r_offset();
6471 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6472 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6475 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6477 || r_sym >= this->local_symbol_count()
6481 // This is the relocation for the first word of the first EXIDX entry.
6482 // We expect to see a local section symbol.
6483 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6484 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6485 if (sym.get_st_type() == elfcpp::STT_SECTION)
6489 this->adjust_sym_shndx(r_sym, sym.get_st_shndx(), &is_ordinary);
6490 gold_assert(is_ordinary);
6500 // Make an EXIDX input section object for an EXIDX section whose index is
6501 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6502 // is the section index of the linked text section.
6504 template<bool big_endian>
6506 Arm_relobj<big_endian>::make_exidx_input_section(
6508 const elfcpp::Shdr<32, big_endian>& shdr,
6509 unsigned int text_shndx,
6510 const elfcpp::Shdr<32, big_endian>& text_shdr)
6512 // Create an Arm_exidx_input_section object for this EXIDX section.
6513 Arm_exidx_input_section* exidx_input_section =
6514 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6515 shdr.get_sh_addralign());
6517 gold_assert(this->exidx_section_map_[shndx] == NULL);
6518 this->exidx_section_map_[shndx] = exidx_input_section;
6520 if (text_shndx == elfcpp::SHN_UNDEF || text_shndx >= this->shnum())
6522 gold_error(_("EXIDX section %s(%u) links to invalid section %u in %s"),
6523 this->section_name(shndx).c_str(), shndx, text_shndx,
6524 this->name().c_str());
6525 exidx_input_section->set_has_errors();
6527 else if (this->exidx_section_map_[text_shndx] != NULL)
6529 unsigned other_exidx_shndx =
6530 this->exidx_section_map_[text_shndx]->shndx();
6531 gold_error(_("EXIDX sections %s(%u) and %s(%u) both link to text section"
6533 this->section_name(shndx).c_str(), shndx,
6534 this->section_name(other_exidx_shndx).c_str(),
6535 other_exidx_shndx, this->section_name(text_shndx).c_str(),
6536 text_shndx, this->name().c_str());
6537 exidx_input_section->set_has_errors();
6540 this->exidx_section_map_[text_shndx] = exidx_input_section;
6542 // Check section flags of text section.
6543 if ((text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
6545 gold_error(_("EXIDX section %s(%u) links to non-allocated section %s(%u) "
6547 this->section_name(shndx).c_str(), shndx,
6548 this->section_name(text_shndx).c_str(), text_shndx,
6549 this->name().c_str());
6550 exidx_input_section->set_has_errors();
6552 else if ((text_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) == 0)
6553 // I would like to make this an error but currenlty ld just ignores
6555 gold_warning(_("EXIDX section %s(%u) links to non-executable section "
6557 this->section_name(shndx).c_str(), shndx,
6558 this->section_name(text_shndx).c_str(), text_shndx,
6559 this->name().c_str());
6562 // Read the symbol information.
6564 template<bool big_endian>
6566 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6568 // Call parent class to read symbol information.
6569 Sized_relobj<32, big_endian>::do_read_symbols(sd);
6571 // If this input file is a binary file, it has no processor
6572 // specific flags and attributes section.
6573 Input_file::Format format = this->input_file()->format();
6574 if (format != Input_file::FORMAT_ELF)
6576 gold_assert(format == Input_file::FORMAT_BINARY);
6577 this->merge_flags_and_attributes_ = false;
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 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6590 std::vector<unsigned int> deferred_exidx_sections;
6591 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6592 const unsigned char* pshdrs = sd->section_headers->data();
6593 const unsigned char *ps = pshdrs + shdr_size;
6594 bool must_merge_flags_and_attributes = false;
6595 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6597 elfcpp::Shdr<32, big_endian> shdr(ps);
6599 // Sometimes an object has no contents except the section name string
6600 // table and an empty symbol table with the undefined symbol. We
6601 // don't want to merge processor-specific flags from such an object.
6602 if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
6604 // Symbol table is not empty.
6605 const elfcpp::Elf_types<32>::Elf_WXword sym_size =
6606 elfcpp::Elf_sizes<32>::sym_size;
6607 if (shdr.get_sh_size() > sym_size)
6608 must_merge_flags_and_attributes = true;
6610 else if (shdr.get_sh_type() != elfcpp::SHT_STRTAB)
6611 // If this is neither an empty symbol table nor a string table,
6613 must_merge_flags_and_attributes = true;
6615 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6617 gold_assert(this->attributes_section_data_ == NULL);
6618 section_offset_type section_offset = shdr.get_sh_offset();
6619 section_size_type section_size =
6620 convert_to_section_size_type(shdr.get_sh_size());
6621 File_view* view = this->get_lasting_view(section_offset,
6622 section_size, true, false);
6623 this->attributes_section_data_ =
6624 new Attributes_section_data(view->data(), section_size);
6626 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6628 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6629 if (text_shndx == elfcpp::SHN_UNDEF)
6630 deferred_exidx_sections.push_back(i);
6633 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6634 + text_shndx * shdr_size);
6635 this->make_exidx_input_section(i, shdr, text_shndx, text_shdr);
6641 if (!must_merge_flags_and_attributes)
6643 gold_assert(deferred_exidx_sections.empty());
6644 this->merge_flags_and_attributes_ = false;
6648 // Some tools are broken and they do not set the link of EXIDX sections.
6649 // We look at the first relocation to figure out the linked sections.
6650 if (!deferred_exidx_sections.empty())
6652 // We need to go over the section headers again to find the mapping
6653 // from sections being relocated to their relocation sections. This is
6654 // a bit inefficient as we could do that in the loop above. However,
6655 // we do not expect any deferred EXIDX sections normally. So we do not
6656 // want to slow down the most common path.
6657 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6658 Reloc_map reloc_map;
6659 ps = pshdrs + shdr_size;
6660 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6662 elfcpp::Shdr<32, big_endian> shdr(ps);
6663 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6664 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6666 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6667 if (info_shndx >= this->shnum())
6668 gold_error(_("relocation section %u has invalid info %u"),
6670 Reloc_map::value_type value(info_shndx, i);
6671 std::pair<Reloc_map::iterator, bool> result =
6672 reloc_map.insert(value);
6674 gold_error(_("section %u has multiple relocation sections "
6676 info_shndx, i, reloc_map[info_shndx]);
6680 // Read the symbol table section header.
6681 const unsigned int symtab_shndx = this->symtab_shndx();
6682 elfcpp::Shdr<32, big_endian>
6683 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6684 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6686 // Read the local symbols.
6687 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6688 const unsigned int loccount = this->local_symbol_count();
6689 gold_assert(loccount == symtabshdr.get_sh_info());
6690 off_t locsize = loccount * sym_size;
6691 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6692 locsize, true, true);
6694 // Process the deferred EXIDX sections.
6695 for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6697 unsigned int shndx = deferred_exidx_sections[i];
6698 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6699 unsigned int text_shndx = elfcpp::SHN_UNDEF;
6700 Reloc_map::const_iterator it = reloc_map.find(shndx);
6701 if (it != reloc_map.end())
6702 find_linked_text_section(pshdrs + it->second * shdr_size,
6703 psyms, &text_shndx);
6704 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6705 + text_shndx * shdr_size);
6706 this->make_exidx_input_section(shndx, shdr, text_shndx, text_shdr);
6711 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6712 // sections for unwinding. These sections are referenced implicitly by
6713 // text sections linked in the section headers. If we ignore these implict
6714 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6715 // will be garbage-collected incorrectly. Hence we override the same function
6716 // in the base class to handle these implicit references.
6718 template<bool big_endian>
6720 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6722 Read_relocs_data* rd)
6724 // First, call base class method to process relocations in this object.
6725 Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6727 // If --gc-sections is not specified, there is nothing more to do.
6728 // This happens when --icf is used but --gc-sections is not.
6729 if (!parameters->options().gc_sections())
6732 unsigned int shnum = this->shnum();
6733 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6734 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6738 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6739 // to these from the linked text sections.
6740 const unsigned char* ps = pshdrs + shdr_size;
6741 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6743 elfcpp::Shdr<32, big_endian> shdr(ps);
6744 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6746 // Found an .ARM.exidx section, add it to the set of reachable
6747 // sections from its linked text section.
6748 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6749 symtab->gc()->add_reference(this, text_shndx, this, i);
6754 // Update output local symbol count. Owing to EXIDX entry merging, some local
6755 // symbols will be removed in output. Adjust output local symbol count
6756 // accordingly. We can only changed the static output local symbol count. It
6757 // is too late to change the dynamic symbols.
6759 template<bool big_endian>
6761 Arm_relobj<big_endian>::update_output_local_symbol_count()
6763 // Caller should check that this needs updating. We want caller checking
6764 // because output_local_symbol_count_needs_update() is most likely inlined.
6765 gold_assert(this->output_local_symbol_count_needs_update_);
6767 gold_assert(this->symtab_shndx() != -1U);
6768 if (this->symtab_shndx() == 0)
6770 // This object has no symbols. Weird but legal.
6774 // Read the symbol table section header.
6775 const unsigned int symtab_shndx = this->symtab_shndx();
6776 elfcpp::Shdr<32, big_endian>
6777 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6778 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6780 // Read the local symbols.
6781 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6782 const unsigned int loccount = this->local_symbol_count();
6783 gold_assert(loccount == symtabshdr.get_sh_info());
6784 off_t locsize = loccount * sym_size;
6785 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6786 locsize, true, true);
6788 // Loop over the local symbols.
6790 typedef typename Sized_relobj<32, big_endian>::Output_sections
6792 const Output_sections& out_sections(this->output_sections());
6793 unsigned int shnum = this->shnum();
6794 unsigned int count = 0;
6795 // Skip the first, dummy, symbol.
6797 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6799 elfcpp::Sym<32, big_endian> sym(psyms);
6801 Symbol_value<32>& lv((*this->local_values())[i]);
6803 // This local symbol was already discarded by do_count_local_symbols.
6804 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6808 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6813 Output_section* os = out_sections[shndx];
6815 // This local symbol no longer has an output section. Discard it.
6818 lv.set_no_output_symtab_entry();
6822 // Currently we only discard parts of EXIDX input sections.
6823 // We explicitly check for a merged EXIDX input section to avoid
6824 // calling Output_section_data::output_offset unless necessary.
6825 if ((this->get_output_section_offset(shndx) == invalid_address)
6826 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6828 section_offset_type output_offset =
6829 os->output_offset(this, shndx, lv.input_value());
6830 if (output_offset == -1)
6832 // This symbol is defined in a part of an EXIDX input section
6833 // that is discarded due to entry merging.
6834 lv.set_no_output_symtab_entry();
6843 this->set_output_local_symbol_count(count);
6844 this->output_local_symbol_count_needs_update_ = false;
6847 // Arm_dynobj methods.
6849 // Read the symbol information.
6851 template<bool big_endian>
6853 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6855 // Call parent class to read symbol information.
6856 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6858 // Read processor-specific flags in ELF file header.
6859 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6860 elfcpp::Elf_sizes<32>::ehdr_size,
6862 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6863 this->processor_specific_flags_ = ehdr.get_e_flags();
6865 // Read the attributes section if there is one.
6866 // We read from the end because gas seems to put it near the end of
6867 // the section headers.
6868 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6869 const unsigned char *ps =
6870 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6871 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6873 elfcpp::Shdr<32, big_endian> shdr(ps);
6874 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6876 section_offset_type section_offset = shdr.get_sh_offset();
6877 section_size_type section_size =
6878 convert_to_section_size_type(shdr.get_sh_size());
6879 File_view* view = this->get_lasting_view(section_offset,
6880 section_size, true, false);
6881 this->attributes_section_data_ =
6882 new Attributes_section_data(view->data(), section_size);
6888 // Stub_addend_reader methods.
6890 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6892 template<bool big_endian>
6893 elfcpp::Elf_types<32>::Elf_Swxword
6894 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
6895 unsigned int r_type,
6896 const unsigned char* view,
6897 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
6899 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
6903 case elfcpp::R_ARM_CALL:
6904 case elfcpp::R_ARM_JUMP24:
6905 case elfcpp::R_ARM_PLT32:
6907 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6908 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6909 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
6910 return utils::sign_extend<26>(val << 2);
6913 case elfcpp::R_ARM_THM_CALL:
6914 case elfcpp::R_ARM_THM_JUMP24:
6915 case elfcpp::R_ARM_THM_XPC22:
6917 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6918 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6919 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6920 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6921 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
6924 case elfcpp::R_ARM_THM_JUMP19:
6926 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6927 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6928 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6929 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6930 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
6938 // Arm_output_data_got methods.
6940 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
6941 // The first one is initialized to be 1, which is the module index for
6942 // the main executable and the second one 0. A reloc of the type
6943 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
6944 // be applied by gold. GSYM is a global symbol.
6946 template<bool big_endian>
6948 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6949 unsigned int got_type,
6952 if (gsym->has_got_offset(got_type))
6955 // We are doing a static link. Just mark it as belong to module 1,
6957 unsigned int got_offset = this->add_constant(1);
6958 gsym->set_got_offset(got_type, got_offset);
6959 got_offset = this->add_constant(0);
6960 this->static_relocs_.push_back(Static_reloc(got_offset,
6961 elfcpp::R_ARM_TLS_DTPOFF32,
6965 // Same as the above but for a local symbol.
6967 template<bool big_endian>
6969 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6970 unsigned int got_type,
6971 Sized_relobj<32, big_endian>* object,
6974 if (object->local_has_got_offset(index, got_type))
6977 // We are doing a static link. Just mark it as belong to module 1,
6979 unsigned int got_offset = this->add_constant(1);
6980 object->set_local_got_offset(index, got_type, got_offset);
6981 got_offset = this->add_constant(0);
6982 this->static_relocs_.push_back(Static_reloc(got_offset,
6983 elfcpp::R_ARM_TLS_DTPOFF32,
6987 template<bool big_endian>
6989 Arm_output_data_got<big_endian>::do_write(Output_file* of)
6991 // Call parent to write out GOT.
6992 Output_data_got<32, big_endian>::do_write(of);
6994 // We are done if there is no fix up.
6995 if (this->static_relocs_.empty())
6998 gold_assert(parameters->doing_static_link());
7000 const off_t offset = this->offset();
7001 const section_size_type oview_size =
7002 convert_to_section_size_type(this->data_size());
7003 unsigned char* const oview = of->get_output_view(offset, oview_size);
7005 Output_segment* tls_segment = this->layout_->tls_segment();
7006 gold_assert(tls_segment != NULL);
7008 // The thread pointer $tp points to the TCB, which is followed by the
7009 // TLS. So we need to adjust $tp relative addressing by this amount.
7010 Arm_address aligned_tcb_size =
7011 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
7013 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
7015 Static_reloc& reloc(this->static_relocs_[i]);
7018 if (!reloc.symbol_is_global())
7020 Sized_relobj<32, big_endian>* object = reloc.relobj();
7021 const Symbol_value<32>* psymval =
7022 reloc.relobj()->local_symbol(reloc.index());
7024 // We are doing static linking. Issue an error and skip this
7025 // relocation if the symbol is undefined or in a discarded_section.
7027 unsigned int shndx = psymval->input_shndx(&is_ordinary);
7028 if ((shndx == elfcpp::SHN_UNDEF)
7030 && shndx != elfcpp::SHN_UNDEF
7031 && !object->is_section_included(shndx)
7032 && !this->symbol_table_->is_section_folded(object, shndx)))
7034 gold_error(_("undefined or discarded local symbol %u from "
7035 " object %s in GOT"),
7036 reloc.index(), reloc.relobj()->name().c_str());
7040 value = psymval->value(object, 0);
7044 const Symbol* gsym = reloc.symbol();
7045 gold_assert(gsym != NULL);
7046 if (gsym->is_forwarder())
7047 gsym = this->symbol_table_->resolve_forwards(gsym);
7049 // We are doing static linking. Issue an error and skip this
7050 // relocation if the symbol is undefined or in a discarded_section
7051 // unless it is a weakly_undefined symbol.
7052 if ((gsym->is_defined_in_discarded_section()
7053 || gsym->is_undefined())
7054 && !gsym->is_weak_undefined())
7056 gold_error(_("undefined or discarded symbol %s in GOT"),
7061 if (!gsym->is_weak_undefined())
7063 const Sized_symbol<32>* sym =
7064 static_cast<const Sized_symbol<32>*>(gsym);
7065 value = sym->value();
7071 unsigned got_offset = reloc.got_offset();
7072 gold_assert(got_offset < oview_size);
7074 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
7075 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
7077 switch (reloc.r_type())
7079 case elfcpp::R_ARM_TLS_DTPOFF32:
7082 case elfcpp::R_ARM_TLS_TPOFF32:
7083 x = value + aligned_tcb_size;
7088 elfcpp::Swap<32, big_endian>::writeval(wv, x);
7091 of->write_output_view(offset, oview_size, oview);
7094 // A class to handle the PLT data.
7096 template<bool big_endian>
7097 class Output_data_plt_arm : public Output_section_data
7100 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
7103 Output_data_plt_arm(Layout*, Output_data_space*);
7105 // Add an entry to the PLT.
7107 add_entry(Symbol* gsym);
7109 // Return the .rel.plt section data.
7110 const Reloc_section*
7112 { return this->rel_; }
7116 do_adjust_output_section(Output_section* os);
7118 // Write to a map file.
7120 do_print_to_mapfile(Mapfile* mapfile) const
7121 { mapfile->print_output_data(this, _("** PLT")); }
7124 // Template for the first PLT entry.
7125 static const uint32_t first_plt_entry[5];
7127 // Template for subsequent PLT entries.
7128 static const uint32_t plt_entry[3];
7130 // Set the final size.
7132 set_final_data_size()
7134 this->set_data_size(sizeof(first_plt_entry)
7135 + this->count_ * sizeof(plt_entry));
7138 // Write out the PLT data.
7140 do_write(Output_file*);
7142 // The reloc section.
7143 Reloc_section* rel_;
7144 // The .got.plt section.
7145 Output_data_space* got_plt_;
7146 // The number of PLT entries.
7147 unsigned int count_;
7150 // Create the PLT section. The ordinary .got section is an argument,
7151 // since we need to refer to the start. We also create our own .got
7152 // section just for PLT entries.
7154 template<bool big_endian>
7155 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
7156 Output_data_space* got_plt)
7157 : Output_section_data(4), got_plt_(got_plt), count_(0)
7159 this->rel_ = new Reloc_section(false);
7160 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
7161 elfcpp::SHF_ALLOC, this->rel_,
7162 ORDER_DYNAMIC_PLT_RELOCS, false);
7165 template<bool big_endian>
7167 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
7172 // Add an entry to the PLT.
7174 template<bool big_endian>
7176 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
7178 gold_assert(!gsym->has_plt_offset());
7180 // Note that when setting the PLT offset we skip the initial
7181 // reserved PLT entry.
7182 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
7183 + sizeof(first_plt_entry));
7187 section_offset_type got_offset = this->got_plt_->current_data_size();
7189 // Every PLT entry needs a GOT entry which points back to the PLT
7190 // entry (this will be changed by the dynamic linker, normally
7191 // lazily when the function is called).
7192 this->got_plt_->set_current_data_size(got_offset + 4);
7194 // Every PLT entry needs a reloc.
7195 gsym->set_needs_dynsym_entry();
7196 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
7199 // Note that we don't need to save the symbol. The contents of the
7200 // PLT are independent of which symbols are used. The symbols only
7201 // appear in the relocations.
7205 // FIXME: This is not very flexible. Right now this has only been tested
7206 // on armv5te. If we are to support additional architecture features like
7207 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
7209 // The first entry in the PLT.
7210 template<bool big_endian>
7211 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
7213 0xe52de004, // str lr, [sp, #-4]!
7214 0xe59fe004, // ldr lr, [pc, #4]
7215 0xe08fe00e, // add lr, pc, lr
7216 0xe5bef008, // ldr pc, [lr, #8]!
7217 0x00000000, // &GOT[0] - .
7220 // Subsequent entries in the PLT.
7222 template<bool big_endian>
7223 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
7225 0xe28fc600, // add ip, pc, #0xNN00000
7226 0xe28cca00, // add ip, ip, #0xNN000
7227 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
7230 // Write out the PLT. This uses the hand-coded instructions above,
7231 // and adjusts them as needed. This is all specified by the arm ELF
7232 // Processor Supplement.
7234 template<bool big_endian>
7236 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
7238 const off_t offset = this->offset();
7239 const section_size_type oview_size =
7240 convert_to_section_size_type(this->data_size());
7241 unsigned char* const oview = of->get_output_view(offset, oview_size);
7243 const off_t got_file_offset = this->got_plt_->offset();
7244 const section_size_type got_size =
7245 convert_to_section_size_type(this->got_plt_->data_size());
7246 unsigned char* const got_view = of->get_output_view(got_file_offset,
7248 unsigned char* pov = oview;
7250 Arm_address plt_address = this->address();
7251 Arm_address got_address = this->got_plt_->address();
7253 // Write first PLT entry. All but the last word are constants.
7254 const size_t num_first_plt_words = (sizeof(first_plt_entry)
7255 / sizeof(plt_entry[0]));
7256 for (size_t i = 0; i < num_first_plt_words - 1; i++)
7257 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
7258 // Last word in first PLT entry is &GOT[0] - .
7259 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
7260 got_address - (plt_address + 16));
7261 pov += sizeof(first_plt_entry);
7263 unsigned char* got_pov = got_view;
7265 memset(got_pov, 0, 12);
7268 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
7269 unsigned int plt_offset = sizeof(first_plt_entry);
7270 unsigned int plt_rel_offset = 0;
7271 unsigned int got_offset = 12;
7272 const unsigned int count = this->count_;
7273 for (unsigned int i = 0;
7276 pov += sizeof(plt_entry),
7278 plt_offset += sizeof(plt_entry),
7279 plt_rel_offset += rel_size,
7282 // Set and adjust the PLT entry itself.
7283 int32_t offset = ((got_address + got_offset)
7284 - (plt_address + plt_offset + 8));
7286 gold_assert(offset >= 0 && offset < 0x0fffffff);
7287 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
7288 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
7289 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
7290 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
7291 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
7292 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7294 // Set the entry in the GOT.
7295 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7298 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7299 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7301 of->write_output_view(offset, oview_size, oview);
7302 of->write_output_view(got_file_offset, got_size, got_view);
7305 // Create a PLT entry for a global symbol.
7307 template<bool big_endian>
7309 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7312 if (gsym->has_plt_offset())
7315 if (this->plt_ == NULL)
7317 // Create the GOT sections first.
7318 this->got_section(symtab, layout);
7320 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
7321 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7323 | elfcpp::SHF_EXECINSTR),
7324 this->plt_, ORDER_PLT, false);
7326 this->plt_->add_entry(gsym);
7329 // Get the section to use for TLS_DESC relocations.
7331 template<bool big_endian>
7332 typename Target_arm<big_endian>::Reloc_section*
7333 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7335 return this->plt_section()->rel_tls_desc(layout);
7338 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7340 template<bool big_endian>
7342 Target_arm<big_endian>::define_tls_base_symbol(
7343 Symbol_table* symtab,
7346 if (this->tls_base_symbol_defined_)
7349 Output_segment* tls_segment = layout->tls_segment();
7350 if (tls_segment != NULL)
7352 bool is_exec = parameters->options().output_is_executable();
7353 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7354 Symbol_table::PREDEFINED,
7358 elfcpp::STV_HIDDEN, 0,
7360 ? Symbol::SEGMENT_END
7361 : Symbol::SEGMENT_START),
7364 this->tls_base_symbol_defined_ = true;
7367 // Create a GOT entry for the TLS module index.
7369 template<bool big_endian>
7371 Target_arm<big_endian>::got_mod_index_entry(
7372 Symbol_table* symtab,
7374 Sized_relobj<32, big_endian>* object)
7376 if (this->got_mod_index_offset_ == -1U)
7378 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7379 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7380 unsigned int got_offset;
7381 if (!parameters->doing_static_link())
7383 got_offset = got->add_constant(0);
7384 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7385 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7390 // We are doing a static link. Just mark it as belong to module 1,
7392 got_offset = got->add_constant(1);
7395 got->add_constant(0);
7396 this->got_mod_index_offset_ = got_offset;
7398 return this->got_mod_index_offset_;
7401 // Optimize the TLS relocation type based on what we know about the
7402 // symbol. IS_FINAL is true if the final address of this symbol is
7403 // known at link time.
7405 template<bool big_endian>
7406 tls::Tls_optimization
7407 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7409 // FIXME: Currently we do not do any TLS optimization.
7410 return tls::TLSOPT_NONE;
7413 // Report an unsupported relocation against a local symbol.
7415 template<bool big_endian>
7417 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7418 Sized_relobj<32, big_endian>* object,
7419 unsigned int r_type)
7421 gold_error(_("%s: unsupported reloc %u against local symbol"),
7422 object->name().c_str(), r_type);
7425 // We are about to emit a dynamic relocation of type R_TYPE. If the
7426 // dynamic linker does not support it, issue an error. The GNU linker
7427 // only issues a non-PIC error for an allocated read-only section.
7428 // Here we know the section is allocated, but we don't know that it is
7429 // read-only. But we check for all the relocation types which the
7430 // glibc dynamic linker supports, so it seems appropriate to issue an
7431 // error even if the section is not read-only.
7433 template<bool big_endian>
7435 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7436 unsigned int r_type)
7440 // These are the relocation types supported by glibc for ARM.
7441 case elfcpp::R_ARM_RELATIVE:
7442 case elfcpp::R_ARM_COPY:
7443 case elfcpp::R_ARM_GLOB_DAT:
7444 case elfcpp::R_ARM_JUMP_SLOT:
7445 case elfcpp::R_ARM_ABS32:
7446 case elfcpp::R_ARM_ABS32_NOI:
7447 case elfcpp::R_ARM_PC24:
7448 // FIXME: The following 3 types are not supported by Android's dynamic
7450 case elfcpp::R_ARM_TLS_DTPMOD32:
7451 case elfcpp::R_ARM_TLS_DTPOFF32:
7452 case elfcpp::R_ARM_TLS_TPOFF32:
7457 // This prevents us from issuing more than one error per reloc
7458 // section. But we can still wind up issuing more than one
7459 // error per object file.
7460 if (this->issued_non_pic_error_)
7462 const Arm_reloc_property* reloc_property =
7463 arm_reloc_property_table->get_reloc_property(r_type);
7464 gold_assert(reloc_property != NULL);
7465 object->error(_("requires unsupported dynamic reloc %s; "
7466 "recompile with -fPIC"),
7467 reloc_property->name().c_str());
7468 this->issued_non_pic_error_ = true;
7472 case elfcpp::R_ARM_NONE:
7477 // Scan a relocation for a local symbol.
7478 // FIXME: This only handles a subset of relocation types used by Android
7479 // on ARM v5te devices.
7481 template<bool big_endian>
7483 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7486 Sized_relobj<32, big_endian>* object,
7487 unsigned int data_shndx,
7488 Output_section* output_section,
7489 const elfcpp::Rel<32, big_endian>& reloc,
7490 unsigned int r_type,
7491 const elfcpp::Sym<32, big_endian>& lsym)
7493 r_type = get_real_reloc_type(r_type);
7496 case elfcpp::R_ARM_NONE:
7497 case elfcpp::R_ARM_V4BX:
7498 case elfcpp::R_ARM_GNU_VTENTRY:
7499 case elfcpp::R_ARM_GNU_VTINHERIT:
7502 case elfcpp::R_ARM_ABS32:
7503 case elfcpp::R_ARM_ABS32_NOI:
7504 // If building a shared library (or a position-independent
7505 // executable), we need to create a dynamic relocation for
7506 // this location. The relocation applied at link time will
7507 // apply the link-time value, so we flag the location with
7508 // an R_ARM_RELATIVE relocation so the dynamic loader can
7509 // relocate it easily.
7510 if (parameters->options().output_is_position_independent())
7512 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7513 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7514 // If we are to add more other reloc types than R_ARM_ABS32,
7515 // we need to add check_non_pic(object, r_type) here.
7516 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7517 output_section, data_shndx,
7518 reloc.get_r_offset());
7522 case elfcpp::R_ARM_ABS16:
7523 case elfcpp::R_ARM_ABS12:
7524 case elfcpp::R_ARM_THM_ABS5:
7525 case elfcpp::R_ARM_ABS8:
7526 case elfcpp::R_ARM_BASE_ABS:
7527 case elfcpp::R_ARM_MOVW_ABS_NC:
7528 case elfcpp::R_ARM_MOVT_ABS:
7529 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7530 case elfcpp::R_ARM_THM_MOVT_ABS:
7531 // If building a shared library (or a position-independent
7532 // executable), we need to create a dynamic relocation for
7533 // this location. Because the addend needs to remain in the
7534 // data section, we need to be careful not to apply this
7535 // relocation statically.
7536 if (parameters->options().output_is_position_independent())
7538 check_non_pic(object, r_type);
7539 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7540 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7541 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7542 rel_dyn->add_local(object, r_sym, r_type, output_section,
7543 data_shndx, reloc.get_r_offset());
7546 gold_assert(lsym.get_st_value() == 0);
7547 unsigned int shndx = lsym.get_st_shndx();
7549 shndx = object->adjust_sym_shndx(r_sym, shndx,
7552 object->error(_("section symbol %u has bad shndx %u"),
7555 rel_dyn->add_local_section(object, shndx,
7556 r_type, output_section,
7557 data_shndx, reloc.get_r_offset());
7562 case elfcpp::R_ARM_PC24:
7563 case elfcpp::R_ARM_REL32:
7564 case elfcpp::R_ARM_LDR_PC_G0:
7565 case elfcpp::R_ARM_SBREL32:
7566 case elfcpp::R_ARM_THM_CALL:
7567 case elfcpp::R_ARM_THM_PC8:
7568 case elfcpp::R_ARM_BASE_PREL:
7569 case elfcpp::R_ARM_PLT32:
7570 case elfcpp::R_ARM_CALL:
7571 case elfcpp::R_ARM_JUMP24:
7572 case elfcpp::R_ARM_THM_JUMP24:
7573 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7574 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7575 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7576 case elfcpp::R_ARM_SBREL31:
7577 case elfcpp::R_ARM_PREL31:
7578 case elfcpp::R_ARM_MOVW_PREL_NC:
7579 case elfcpp::R_ARM_MOVT_PREL:
7580 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7581 case elfcpp::R_ARM_THM_MOVT_PREL:
7582 case elfcpp::R_ARM_THM_JUMP19:
7583 case elfcpp::R_ARM_THM_JUMP6:
7584 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7585 case elfcpp::R_ARM_THM_PC12:
7586 case elfcpp::R_ARM_REL32_NOI:
7587 case elfcpp::R_ARM_ALU_PC_G0_NC:
7588 case elfcpp::R_ARM_ALU_PC_G0:
7589 case elfcpp::R_ARM_ALU_PC_G1_NC:
7590 case elfcpp::R_ARM_ALU_PC_G1:
7591 case elfcpp::R_ARM_ALU_PC_G2:
7592 case elfcpp::R_ARM_LDR_PC_G1:
7593 case elfcpp::R_ARM_LDR_PC_G2:
7594 case elfcpp::R_ARM_LDRS_PC_G0:
7595 case elfcpp::R_ARM_LDRS_PC_G1:
7596 case elfcpp::R_ARM_LDRS_PC_G2:
7597 case elfcpp::R_ARM_LDC_PC_G0:
7598 case elfcpp::R_ARM_LDC_PC_G1:
7599 case elfcpp::R_ARM_LDC_PC_G2:
7600 case elfcpp::R_ARM_ALU_SB_G0_NC:
7601 case elfcpp::R_ARM_ALU_SB_G0:
7602 case elfcpp::R_ARM_ALU_SB_G1_NC:
7603 case elfcpp::R_ARM_ALU_SB_G1:
7604 case elfcpp::R_ARM_ALU_SB_G2:
7605 case elfcpp::R_ARM_LDR_SB_G0:
7606 case elfcpp::R_ARM_LDR_SB_G1:
7607 case elfcpp::R_ARM_LDR_SB_G2:
7608 case elfcpp::R_ARM_LDRS_SB_G0:
7609 case elfcpp::R_ARM_LDRS_SB_G1:
7610 case elfcpp::R_ARM_LDRS_SB_G2:
7611 case elfcpp::R_ARM_LDC_SB_G0:
7612 case elfcpp::R_ARM_LDC_SB_G1:
7613 case elfcpp::R_ARM_LDC_SB_G2:
7614 case elfcpp::R_ARM_MOVW_BREL_NC:
7615 case elfcpp::R_ARM_MOVT_BREL:
7616 case elfcpp::R_ARM_MOVW_BREL:
7617 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7618 case elfcpp::R_ARM_THM_MOVT_BREL:
7619 case elfcpp::R_ARM_THM_MOVW_BREL:
7620 case elfcpp::R_ARM_THM_JUMP11:
7621 case elfcpp::R_ARM_THM_JUMP8:
7622 // We don't need to do anything for a relative addressing relocation
7623 // against a local symbol if it does not reference the GOT.
7626 case elfcpp::R_ARM_GOTOFF32:
7627 case elfcpp::R_ARM_GOTOFF12:
7628 // We need a GOT section:
7629 target->got_section(symtab, layout);
7632 case elfcpp::R_ARM_GOT_BREL:
7633 case elfcpp::R_ARM_GOT_PREL:
7635 // The symbol requires a GOT entry.
7636 Arm_output_data_got<big_endian>* got =
7637 target->got_section(symtab, layout);
7638 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7639 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
7641 // If we are generating a shared object, we need to add a
7642 // dynamic RELATIVE relocation for this symbol's GOT entry.
7643 if (parameters->options().output_is_position_independent())
7645 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7646 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7647 rel_dyn->add_local_relative(
7648 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
7649 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
7655 case elfcpp::R_ARM_TARGET1:
7656 case elfcpp::R_ARM_TARGET2:
7657 // This should have been mapped to another type already.
7659 case elfcpp::R_ARM_COPY:
7660 case elfcpp::R_ARM_GLOB_DAT:
7661 case elfcpp::R_ARM_JUMP_SLOT:
7662 case elfcpp::R_ARM_RELATIVE:
7663 // These are relocations which should only be seen by the
7664 // dynamic linker, and should never be seen here.
7665 gold_error(_("%s: unexpected reloc %u in object file"),
7666 object->name().c_str(), r_type);
7670 // These are initial TLS relocs, which are expected when
7672 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7673 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7674 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7675 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7676 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7678 bool output_is_shared = parameters->options().shared();
7679 const tls::Tls_optimization optimized_type
7680 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
7684 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7685 if (optimized_type == tls::TLSOPT_NONE)
7687 // Create a pair of GOT entries for the module index and
7688 // dtv-relative offset.
7689 Arm_output_data_got<big_endian>* got
7690 = target->got_section(symtab, layout);
7691 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7692 unsigned int shndx = lsym.get_st_shndx();
7694 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
7697 object->error(_("local symbol %u has bad shndx %u"),
7702 if (!parameters->doing_static_link())
7703 got->add_local_pair_with_rel(object, r_sym, shndx,
7705 target->rel_dyn_section(layout),
7706 elfcpp::R_ARM_TLS_DTPMOD32, 0);
7708 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
7712 // FIXME: TLS optimization not supported yet.
7716 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7717 if (optimized_type == tls::TLSOPT_NONE)
7719 // Create a GOT entry for the module index.
7720 target->got_mod_index_entry(symtab, layout, object);
7723 // FIXME: TLS optimization not supported yet.
7727 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7730 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7731 layout->set_has_static_tls();
7732 if (optimized_type == tls::TLSOPT_NONE)
7734 // Create a GOT entry for the tp-relative offset.
7735 Arm_output_data_got<big_endian>* got
7736 = target->got_section(symtab, layout);
7737 unsigned int r_sym =
7738 elfcpp::elf_r_sym<32>(reloc.get_r_info());
7739 if (!parameters->doing_static_link())
7740 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
7741 target->rel_dyn_section(layout),
7742 elfcpp::R_ARM_TLS_TPOFF32);
7743 else if (!object->local_has_got_offset(r_sym,
7744 GOT_TYPE_TLS_OFFSET))
7746 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
7747 unsigned int got_offset =
7748 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
7749 got->add_static_reloc(got_offset,
7750 elfcpp::R_ARM_TLS_TPOFF32, object,
7755 // FIXME: TLS optimization not supported yet.
7759 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7760 layout->set_has_static_tls();
7761 if (output_is_shared)
7763 // We need to create a dynamic relocation.
7764 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7765 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7766 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7767 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
7768 output_section, data_shndx,
7769 reloc.get_r_offset());
7780 unsupported_reloc_local(object, r_type);
7785 // Report an unsupported relocation against a global symbol.
7787 template<bool big_endian>
7789 Target_arm<big_endian>::Scan::unsupported_reloc_global(
7790 Sized_relobj<32, big_endian>* object,
7791 unsigned int r_type,
7794 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
7795 object->name().c_str(), r_type, gsym->demangled_name().c_str());
7798 template<bool big_endian>
7800 Target_arm<big_endian>::Scan::possible_function_pointer_reloc(
7801 unsigned int r_type)
7805 case elfcpp::R_ARM_PC24:
7806 case elfcpp::R_ARM_THM_CALL:
7807 case elfcpp::R_ARM_PLT32:
7808 case elfcpp::R_ARM_CALL:
7809 case elfcpp::R_ARM_JUMP24:
7810 case elfcpp::R_ARM_THM_JUMP24:
7811 case elfcpp::R_ARM_SBREL31:
7812 case elfcpp::R_ARM_PREL31:
7813 case elfcpp::R_ARM_THM_JUMP19:
7814 case elfcpp::R_ARM_THM_JUMP6:
7815 case elfcpp::R_ARM_THM_JUMP11:
7816 case elfcpp::R_ARM_THM_JUMP8:
7817 // All the relocations above are branches except SBREL31 and PREL31.
7821 // Be conservative and assume this is a function pointer.
7826 template<bool big_endian>
7828 Target_arm<big_endian>::Scan::local_reloc_may_be_function_pointer(
7831 Target_arm<big_endian>* target,
7832 Sized_relobj<32, big_endian>*,
7835 const elfcpp::Rel<32, big_endian>&,
7836 unsigned int r_type,
7837 const elfcpp::Sym<32, big_endian>&)
7839 r_type = target->get_real_reloc_type(r_type);
7840 return possible_function_pointer_reloc(r_type);
7843 template<bool big_endian>
7845 Target_arm<big_endian>::Scan::global_reloc_may_be_function_pointer(
7848 Target_arm<big_endian>* target,
7849 Sized_relobj<32, big_endian>*,
7852 const elfcpp::Rel<32, big_endian>&,
7853 unsigned int r_type,
7856 // GOT is not a function.
7857 if (strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7860 r_type = target->get_real_reloc_type(r_type);
7861 return possible_function_pointer_reloc(r_type);
7864 // Scan a relocation for a global symbol.
7866 template<bool big_endian>
7868 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
7871 Sized_relobj<32, big_endian>* object,
7872 unsigned int data_shndx,
7873 Output_section* output_section,
7874 const elfcpp::Rel<32, big_endian>& reloc,
7875 unsigned int r_type,
7878 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
7879 // section. We check here to avoid creating a dynamic reloc against
7880 // _GLOBAL_OFFSET_TABLE_.
7881 if (!target->has_got_section()
7882 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7883 target->got_section(symtab, layout);
7885 r_type = get_real_reloc_type(r_type);
7888 case elfcpp::R_ARM_NONE:
7889 case elfcpp::R_ARM_V4BX:
7890 case elfcpp::R_ARM_GNU_VTENTRY:
7891 case elfcpp::R_ARM_GNU_VTINHERIT:
7894 case elfcpp::R_ARM_ABS32:
7895 case elfcpp::R_ARM_ABS16:
7896 case elfcpp::R_ARM_ABS12:
7897 case elfcpp::R_ARM_THM_ABS5:
7898 case elfcpp::R_ARM_ABS8:
7899 case elfcpp::R_ARM_BASE_ABS:
7900 case elfcpp::R_ARM_MOVW_ABS_NC:
7901 case elfcpp::R_ARM_MOVT_ABS:
7902 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7903 case elfcpp::R_ARM_THM_MOVT_ABS:
7904 case elfcpp::R_ARM_ABS32_NOI:
7905 // Absolute addressing relocations.
7907 // Make a PLT entry if necessary.
7908 if (this->symbol_needs_plt_entry(gsym))
7910 target->make_plt_entry(symtab, layout, gsym);
7911 // Since this is not a PC-relative relocation, we may be
7912 // taking the address of a function. In that case we need to
7913 // set the entry in the dynamic symbol table to the address of
7915 if (gsym->is_from_dynobj() && !parameters->options().shared())
7916 gsym->set_needs_dynsym_value();
7918 // Make a dynamic relocation if necessary.
7919 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
7921 if (gsym->may_need_copy_reloc())
7923 target->copy_reloc(symtab, layout, object,
7924 data_shndx, output_section, gsym, reloc);
7926 else if ((r_type == elfcpp::R_ARM_ABS32
7927 || r_type == elfcpp::R_ARM_ABS32_NOI)
7928 && gsym->can_use_relative_reloc(false))
7930 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7931 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
7932 output_section, object,
7933 data_shndx, reloc.get_r_offset());
7937 check_non_pic(object, r_type);
7938 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7939 rel_dyn->add_global(gsym, r_type, output_section, object,
7940 data_shndx, reloc.get_r_offset());
7946 case elfcpp::R_ARM_GOTOFF32:
7947 case elfcpp::R_ARM_GOTOFF12:
7948 // We need a GOT section.
7949 target->got_section(symtab, layout);
7952 case elfcpp::R_ARM_REL32:
7953 case elfcpp::R_ARM_LDR_PC_G0:
7954 case elfcpp::R_ARM_SBREL32:
7955 case elfcpp::R_ARM_THM_PC8:
7956 case elfcpp::R_ARM_BASE_PREL:
7957 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7958 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7959 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7960 case elfcpp::R_ARM_MOVW_PREL_NC:
7961 case elfcpp::R_ARM_MOVT_PREL:
7962 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7963 case elfcpp::R_ARM_THM_MOVT_PREL:
7964 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7965 case elfcpp::R_ARM_THM_PC12:
7966 case elfcpp::R_ARM_REL32_NOI:
7967 case elfcpp::R_ARM_ALU_PC_G0_NC:
7968 case elfcpp::R_ARM_ALU_PC_G0:
7969 case elfcpp::R_ARM_ALU_PC_G1_NC:
7970 case elfcpp::R_ARM_ALU_PC_G1:
7971 case elfcpp::R_ARM_ALU_PC_G2:
7972 case elfcpp::R_ARM_LDR_PC_G1:
7973 case elfcpp::R_ARM_LDR_PC_G2:
7974 case elfcpp::R_ARM_LDRS_PC_G0:
7975 case elfcpp::R_ARM_LDRS_PC_G1:
7976 case elfcpp::R_ARM_LDRS_PC_G2:
7977 case elfcpp::R_ARM_LDC_PC_G0:
7978 case elfcpp::R_ARM_LDC_PC_G1:
7979 case elfcpp::R_ARM_LDC_PC_G2:
7980 case elfcpp::R_ARM_ALU_SB_G0_NC:
7981 case elfcpp::R_ARM_ALU_SB_G0:
7982 case elfcpp::R_ARM_ALU_SB_G1_NC:
7983 case elfcpp::R_ARM_ALU_SB_G1:
7984 case elfcpp::R_ARM_ALU_SB_G2:
7985 case elfcpp::R_ARM_LDR_SB_G0:
7986 case elfcpp::R_ARM_LDR_SB_G1:
7987 case elfcpp::R_ARM_LDR_SB_G2:
7988 case elfcpp::R_ARM_LDRS_SB_G0:
7989 case elfcpp::R_ARM_LDRS_SB_G1:
7990 case elfcpp::R_ARM_LDRS_SB_G2:
7991 case elfcpp::R_ARM_LDC_SB_G0:
7992 case elfcpp::R_ARM_LDC_SB_G1:
7993 case elfcpp::R_ARM_LDC_SB_G2:
7994 case elfcpp::R_ARM_MOVW_BREL_NC:
7995 case elfcpp::R_ARM_MOVT_BREL:
7996 case elfcpp::R_ARM_MOVW_BREL:
7997 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7998 case elfcpp::R_ARM_THM_MOVT_BREL:
7999 case elfcpp::R_ARM_THM_MOVW_BREL:
8000 // Relative addressing relocations.
8002 // Make a dynamic relocation if necessary.
8003 int flags = Symbol::NON_PIC_REF;
8004 if (gsym->needs_dynamic_reloc(flags))
8006 if (target->may_need_copy_reloc(gsym))
8008 target->copy_reloc(symtab, layout, object,
8009 data_shndx, output_section, gsym, reloc);
8013 check_non_pic(object, r_type);
8014 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8015 rel_dyn->add_global(gsym, r_type, output_section, object,
8016 data_shndx, reloc.get_r_offset());
8022 case elfcpp::R_ARM_PC24:
8023 case elfcpp::R_ARM_THM_CALL:
8024 case elfcpp::R_ARM_PLT32:
8025 case elfcpp::R_ARM_CALL:
8026 case elfcpp::R_ARM_JUMP24:
8027 case elfcpp::R_ARM_THM_JUMP24:
8028 case elfcpp::R_ARM_SBREL31:
8029 case elfcpp::R_ARM_PREL31:
8030 case elfcpp::R_ARM_THM_JUMP19:
8031 case elfcpp::R_ARM_THM_JUMP6:
8032 case elfcpp::R_ARM_THM_JUMP11:
8033 case elfcpp::R_ARM_THM_JUMP8:
8034 // All the relocation above are branches except for the PREL31 ones.
8035 // A PREL31 relocation can point to a personality function in a shared
8036 // library. In that case we want to use a PLT because we want to
8037 // call the personality routine and the dyanmic linkers we care about
8038 // do not support dynamic PREL31 relocations. An REL31 relocation may
8039 // point to a function whose unwinding behaviour is being described but
8040 // we will not mistakenly generate a PLT for that because we should use
8041 // a local section symbol.
8043 // If the symbol is fully resolved, this is just a relative
8044 // local reloc. Otherwise we need a PLT entry.
8045 if (gsym->final_value_is_known())
8047 // If building a shared library, we can also skip the PLT entry
8048 // if the symbol is defined in the output file and is protected
8050 if (gsym->is_defined()
8051 && !gsym->is_from_dynobj()
8052 && !gsym->is_preemptible())
8054 target->make_plt_entry(symtab, layout, gsym);
8057 case elfcpp::R_ARM_GOT_BREL:
8058 case elfcpp::R_ARM_GOT_ABS:
8059 case elfcpp::R_ARM_GOT_PREL:
8061 // The symbol requires a GOT entry.
8062 Arm_output_data_got<big_endian>* got =
8063 target->got_section(symtab, layout);
8064 if (gsym->final_value_is_known())
8065 got->add_global(gsym, GOT_TYPE_STANDARD);
8068 // If this symbol is not fully resolved, we need to add a
8069 // GOT entry with a dynamic relocation.
8070 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8071 if (gsym->is_from_dynobj()
8072 || gsym->is_undefined()
8073 || gsym->is_preemptible())
8074 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
8075 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
8078 if (got->add_global(gsym, GOT_TYPE_STANDARD))
8079 rel_dyn->add_global_relative(
8080 gsym, elfcpp::R_ARM_RELATIVE, got,
8081 gsym->got_offset(GOT_TYPE_STANDARD));
8087 case elfcpp::R_ARM_TARGET1:
8088 case elfcpp::R_ARM_TARGET2:
8089 // These should have been mapped to other types already.
8091 case elfcpp::R_ARM_COPY:
8092 case elfcpp::R_ARM_GLOB_DAT:
8093 case elfcpp::R_ARM_JUMP_SLOT:
8094 case elfcpp::R_ARM_RELATIVE:
8095 // These are relocations which should only be seen by the
8096 // dynamic linker, and should never be seen here.
8097 gold_error(_("%s: unexpected reloc %u in object file"),
8098 object->name().c_str(), r_type);
8101 // These are initial tls relocs, which are expected when
8103 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8104 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8105 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8106 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8107 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8109 const bool is_final = gsym->final_value_is_known();
8110 const tls::Tls_optimization optimized_type
8111 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8114 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8115 if (optimized_type == tls::TLSOPT_NONE)
8117 // Create a pair of GOT entries for the module index and
8118 // dtv-relative offset.
8119 Arm_output_data_got<big_endian>* got
8120 = target->got_section(symtab, layout);
8121 if (!parameters->doing_static_link())
8122 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
8123 target->rel_dyn_section(layout),
8124 elfcpp::R_ARM_TLS_DTPMOD32,
8125 elfcpp::R_ARM_TLS_DTPOFF32);
8127 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
8130 // FIXME: TLS optimization not supported yet.
8134 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8135 if (optimized_type == tls::TLSOPT_NONE)
8137 // Create a GOT entry for the module index.
8138 target->got_mod_index_entry(symtab, layout, object);
8141 // FIXME: TLS optimization not supported yet.
8145 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8148 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8149 layout->set_has_static_tls();
8150 if (optimized_type == tls::TLSOPT_NONE)
8152 // Create a GOT entry for the tp-relative offset.
8153 Arm_output_data_got<big_endian>* got
8154 = target->got_section(symtab, layout);
8155 if (!parameters->doing_static_link())
8156 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
8157 target->rel_dyn_section(layout),
8158 elfcpp::R_ARM_TLS_TPOFF32);
8159 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
8161 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
8162 unsigned int got_offset =
8163 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
8164 got->add_static_reloc(got_offset,
8165 elfcpp::R_ARM_TLS_TPOFF32, gsym);
8169 // FIXME: TLS optimization not supported yet.
8173 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8174 layout->set_has_static_tls();
8175 if (parameters->options().shared())
8177 // We need to create a dynamic relocation.
8178 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8179 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
8180 output_section, object,
8181 data_shndx, reloc.get_r_offset());
8192 unsupported_reloc_global(object, r_type, gsym);
8197 // Process relocations for gc.
8199 template<bool big_endian>
8201 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
8203 Sized_relobj<32, big_endian>* object,
8204 unsigned int data_shndx,
8206 const unsigned char* prelocs,
8208 Output_section* output_section,
8209 bool needs_special_offset_handling,
8210 size_t local_symbol_count,
8211 const unsigned char* plocal_symbols)
8213 typedef Target_arm<big_endian> Arm;
8214 typedef typename Target_arm<big_endian>::Scan Scan;
8216 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan,
8217 typename Target_arm::Relocatable_size_for_reloc>(
8226 needs_special_offset_handling,
8231 // Scan relocations for a section.
8233 template<bool big_endian>
8235 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
8237 Sized_relobj<32, big_endian>* object,
8238 unsigned int data_shndx,
8239 unsigned int sh_type,
8240 const unsigned char* prelocs,
8242 Output_section* output_section,
8243 bool needs_special_offset_handling,
8244 size_t local_symbol_count,
8245 const unsigned char* plocal_symbols)
8247 typedef typename Target_arm<big_endian>::Scan Scan;
8248 if (sh_type == elfcpp::SHT_RELA)
8250 gold_error(_("%s: unsupported RELA reloc section"),
8251 object->name().c_str());
8255 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
8264 needs_special_offset_handling,
8269 // Finalize the sections.
8271 template<bool big_endian>
8273 Target_arm<big_endian>::do_finalize_sections(
8275 const Input_objects* input_objects,
8276 Symbol_table* symtab)
8278 bool merged_any_attributes = false;
8279 // Merge processor-specific flags.
8280 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
8281 p != input_objects->relobj_end();
8284 Arm_relobj<big_endian>* arm_relobj =
8285 Arm_relobj<big_endian>::as_arm_relobj(*p);
8286 if (arm_relobj->merge_flags_and_attributes())
8288 this->merge_processor_specific_flags(
8290 arm_relobj->processor_specific_flags());
8291 this->merge_object_attributes(arm_relobj->name().c_str(),
8292 arm_relobj->attributes_section_data());
8293 merged_any_attributes = true;
8297 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
8298 p != input_objects->dynobj_end();
8301 Arm_dynobj<big_endian>* arm_dynobj =
8302 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
8303 this->merge_processor_specific_flags(
8305 arm_dynobj->processor_specific_flags());
8306 this->merge_object_attributes(arm_dynobj->name().c_str(),
8307 arm_dynobj->attributes_section_data());
8308 merged_any_attributes = true;
8311 // Create an empty uninitialized attribute section if we still don't have it
8312 // at this moment. This happens if there is no attributes sections in all
8314 if (this->attributes_section_data_ == NULL)
8315 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
8318 const Object_attribute* cpu_arch_attr =
8319 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
8320 if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
8321 this->set_may_use_blx(true);
8323 // Check if we need to use Cortex-A8 workaround.
8324 if (parameters->options().user_set_fix_cortex_a8())
8325 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
8328 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
8329 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
8331 const Object_attribute* cpu_arch_profile_attr =
8332 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
8333 this->fix_cortex_a8_ =
8334 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
8335 && (cpu_arch_profile_attr->int_value() == 'A'
8336 || cpu_arch_profile_attr->int_value() == 0));
8339 // Check if we can use V4BX interworking.
8340 // The V4BX interworking stub contains BX instruction,
8341 // which is not specified for some profiles.
8342 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
8343 && !this->may_use_blx())
8344 gold_error(_("unable to provide V4BX reloc interworking fix up; "
8345 "the target profile does not support BX instruction"));
8347 // Fill in some more dynamic tags.
8348 const Reloc_section* rel_plt = (this->plt_ == NULL
8350 : this->plt_->rel_plt());
8351 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
8352 this->rel_dyn_, true, false);
8354 // Emit any relocs we saved in an attempt to avoid generating COPY
8356 if (this->copy_relocs_.any_saved_relocs())
8357 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8359 // Handle the .ARM.exidx section.
8360 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8361 if (exidx_section != NULL
8362 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
8363 && !parameters->options().relocatable())
8365 // Create __exidx_start and __exdix_end symbols.
8366 symtab->define_in_output_data("__exidx_start", NULL,
8367 Symbol_table::PREDEFINED,
8368 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8369 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8371 symtab->define_in_output_data("__exidx_end", NULL,
8372 Symbol_table::PREDEFINED,
8373 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8374 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8377 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8378 // the .ARM.exidx section.
8379 if (!layout->script_options()->saw_phdrs_clause())
8381 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
8383 Output_segment* exidx_segment =
8384 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8385 exidx_segment->add_output_section_to_nonload(exidx_section,
8390 // Create an .ARM.attributes section if we have merged any attributes
8392 if (merged_any_attributes)
8394 Output_attributes_section_data* attributes_section =
8395 new Output_attributes_section_data(*this->attributes_section_data_);
8396 layout->add_output_section_data(".ARM.attributes",
8397 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8398 attributes_section, ORDER_INVALID,
8402 // Fix up links in section EXIDX headers.
8403 for (Layout::Section_list::const_iterator p = layout->section_list().begin();
8404 p != layout->section_list().end();
8406 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
8408 Arm_output_section<big_endian>* os =
8409 Arm_output_section<big_endian>::as_arm_output_section(*p);
8410 os->set_exidx_section_link();
8414 // Return whether a direct absolute static relocation needs to be applied.
8415 // In cases where Scan::local() or Scan::global() has created
8416 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8417 // of the relocation is carried in the data, and we must not
8418 // apply the static relocation.
8420 template<bool big_endian>
8422 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8423 const Sized_symbol<32>* gsym,
8426 Output_section* output_section)
8428 // If the output section is not allocated, then we didn't call
8429 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8431 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8434 // For local symbols, we will have created a non-RELATIVE dynamic
8435 // relocation only if (a) the output is position independent,
8436 // (b) the relocation is absolute (not pc- or segment-relative), and
8437 // (c) the relocation is not 32 bits wide.
8439 return !(parameters->options().output_is_position_independent()
8440 && (ref_flags & Symbol::ABSOLUTE_REF)
8443 // For global symbols, we use the same helper routines used in the
8444 // scan pass. If we did not create a dynamic relocation, or if we
8445 // created a RELATIVE dynamic relocation, we should apply the static
8447 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8448 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8449 && gsym->can_use_relative_reloc(ref_flags
8450 & Symbol::FUNCTION_CALL);
8451 return !has_dyn || is_rel;
8454 // Perform a relocation.
8456 template<bool big_endian>
8458 Target_arm<big_endian>::Relocate::relocate(
8459 const Relocate_info<32, big_endian>* relinfo,
8461 Output_section *output_section,
8463 const elfcpp::Rel<32, big_endian>& rel,
8464 unsigned int r_type,
8465 const Sized_symbol<32>* gsym,
8466 const Symbol_value<32>* psymval,
8467 unsigned char* view,
8468 Arm_address address,
8469 section_size_type view_size)
8471 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8473 r_type = get_real_reloc_type(r_type);
8474 const Arm_reloc_property* reloc_property =
8475 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8476 if (reloc_property == NULL)
8478 std::string reloc_name =
8479 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8480 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8481 _("cannot relocate %s in object file"),
8482 reloc_name.c_str());
8486 const Arm_relobj<big_endian>* object =
8487 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8489 // If the final branch target of a relocation is THUMB instruction, this
8490 // is 1. Otherwise it is 0.
8491 Arm_address thumb_bit = 0;
8492 Symbol_value<32> symval;
8493 bool is_weakly_undefined_without_plt = false;
8494 if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8498 // This is a global symbol. Determine if we use PLT and if the
8499 // final target is THUMB.
8500 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
8502 // This uses a PLT, change the symbol value.
8503 symval.set_output_value(target->plt_section()->address()
8504 + gsym->plt_offset());
8507 else if (gsym->is_weak_undefined())
8509 // This is a weakly undefined symbol and we do not use PLT
8510 // for this relocation. A branch targeting this symbol will
8511 // be converted into an NOP.
8512 is_weakly_undefined_without_plt = true;
8514 else if (gsym->is_undefined() && reloc_property->uses_symbol())
8516 // This relocation uses the symbol value but the symbol is
8517 // undefined. Exit early and have the caller reporting an
8523 // Set thumb bit if symbol:
8524 // -Has type STT_ARM_TFUNC or
8525 // -Has type STT_FUNC, is defined and with LSB in value set.
8527 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8528 || (gsym->type() == elfcpp::STT_FUNC
8529 && !gsym->is_undefined()
8530 && ((psymval->value(object, 0) & 1) != 0)))
8537 // This is a local symbol. Determine if the final target is THUMB.
8538 // We saved this information when all the local symbols were read.
8539 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8540 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8541 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8546 // This is a fake relocation synthesized for a stub. It does not have
8547 // a real symbol. We just look at the LSB of the symbol value to
8548 // determine if the target is THUMB or not.
8549 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8552 // Strip LSB if this points to a THUMB target.
8554 && reloc_property->uses_thumb_bit()
8555 && ((psymval->value(object, 0) & 1) != 0))
8557 Arm_address stripped_value =
8558 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8559 symval.set_output_value(stripped_value);
8563 // Get the GOT offset if needed.
8564 // The GOT pointer points to the end of the GOT section.
8565 // We need to subtract the size of the GOT section to get
8566 // the actual offset to use in the relocation.
8567 bool have_got_offset = false;
8568 unsigned int got_offset = 0;
8571 case elfcpp::R_ARM_GOT_BREL:
8572 case elfcpp::R_ARM_GOT_PREL:
8575 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8576 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8577 - target->got_size());
8581 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8582 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
8583 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8584 - target->got_size());
8586 have_got_offset = true;
8593 // To look up relocation stubs, we need to pass the symbol table index of
8595 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8597 // Get the addressing origin of the output segment defining the
8598 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8599 Arm_address sym_origin = 0;
8600 if (reloc_property->uses_symbol_base())
8602 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8603 // R_ARM_BASE_ABS with the NULL symbol will give the
8604 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8605 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8606 sym_origin = target->got_plt_section()->address();
8607 else if (gsym == NULL)
8609 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8610 sym_origin = gsym->output_segment()->vaddr();
8611 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8612 sym_origin = gsym->output_data()->address();
8614 // TODO: Assumes the segment base to be zero for the global symbols
8615 // till the proper support for the segment-base-relative addressing
8616 // will be implemented. This is consistent with GNU ld.
8619 // For relative addressing relocation, find out the relative address base.
8620 Arm_address relative_address_base = 0;
8621 switch(reloc_property->relative_address_base())
8623 case Arm_reloc_property::RAB_NONE:
8624 // Relocations with relative address bases RAB_TLS and RAB_tp are
8625 // handled by relocate_tls. So we do not need to do anything here.
8626 case Arm_reloc_property::RAB_TLS:
8627 case Arm_reloc_property::RAB_tp:
8629 case Arm_reloc_property::RAB_B_S:
8630 relative_address_base = sym_origin;
8632 case Arm_reloc_property::RAB_GOT_ORG:
8633 relative_address_base = target->got_plt_section()->address();
8635 case Arm_reloc_property::RAB_P:
8636 relative_address_base = address;
8638 case Arm_reloc_property::RAB_Pa:
8639 relative_address_base = address & 0xfffffffcU;
8645 typename Arm_relocate_functions::Status reloc_status =
8646 Arm_relocate_functions::STATUS_OKAY;
8647 bool check_overflow = reloc_property->checks_overflow();
8650 case elfcpp::R_ARM_NONE:
8653 case elfcpp::R_ARM_ABS8:
8654 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8656 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
8659 case elfcpp::R_ARM_ABS12:
8660 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8662 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
8665 case elfcpp::R_ARM_ABS16:
8666 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8668 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
8671 case elfcpp::R_ARM_ABS32:
8672 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8674 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8678 case elfcpp::R_ARM_ABS32_NOI:
8679 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8681 // No thumb bit for this relocation: (S + A)
8682 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8686 case elfcpp::R_ARM_MOVW_ABS_NC:
8687 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8689 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
8694 case elfcpp::R_ARM_MOVT_ABS:
8695 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8697 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
8700 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8701 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8703 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
8704 0, thumb_bit, false);
8707 case elfcpp::R_ARM_THM_MOVT_ABS:
8708 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8710 reloc_status = Arm_relocate_functions::thm_movt(view, object,
8714 case elfcpp::R_ARM_MOVW_PREL_NC:
8715 case elfcpp::R_ARM_MOVW_BREL_NC:
8716 case elfcpp::R_ARM_MOVW_BREL:
8718 Arm_relocate_functions::movw(view, object, psymval,
8719 relative_address_base, thumb_bit,
8723 case elfcpp::R_ARM_MOVT_PREL:
8724 case elfcpp::R_ARM_MOVT_BREL:
8726 Arm_relocate_functions::movt(view, object, psymval,
8727 relative_address_base);
8730 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8731 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8732 case elfcpp::R_ARM_THM_MOVW_BREL:
8734 Arm_relocate_functions::thm_movw(view, object, psymval,
8735 relative_address_base,
8736 thumb_bit, check_overflow);
8739 case elfcpp::R_ARM_THM_MOVT_PREL:
8740 case elfcpp::R_ARM_THM_MOVT_BREL:
8742 Arm_relocate_functions::thm_movt(view, object, psymval,
8743 relative_address_base);
8746 case elfcpp::R_ARM_REL32:
8747 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8748 address, thumb_bit);
8751 case elfcpp::R_ARM_THM_ABS5:
8752 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8754 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
8757 // Thumb long branches.
8758 case elfcpp::R_ARM_THM_CALL:
8759 case elfcpp::R_ARM_THM_XPC22:
8760 case elfcpp::R_ARM_THM_JUMP24:
8762 Arm_relocate_functions::thumb_branch_common(
8763 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8764 thumb_bit, is_weakly_undefined_without_plt);
8767 case elfcpp::R_ARM_GOTOFF32:
8769 Arm_address got_origin;
8770 got_origin = target->got_plt_section()->address();
8771 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8772 got_origin, thumb_bit);
8776 case elfcpp::R_ARM_BASE_PREL:
8777 gold_assert(gsym != NULL);
8779 Arm_relocate_functions::base_prel(view, sym_origin, address);
8782 case elfcpp::R_ARM_BASE_ABS:
8784 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8788 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
8792 case elfcpp::R_ARM_GOT_BREL:
8793 gold_assert(have_got_offset);
8794 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
8797 case elfcpp::R_ARM_GOT_PREL:
8798 gold_assert(have_got_offset);
8799 // Get the address origin for GOT PLT, which is allocated right
8800 // after the GOT section, to calculate an absolute address of
8801 // the symbol GOT entry (got_origin + got_offset).
8802 Arm_address got_origin;
8803 got_origin = target->got_plt_section()->address();
8804 reloc_status = Arm_relocate_functions::got_prel(view,
8805 got_origin + got_offset,
8809 case elfcpp::R_ARM_PLT32:
8810 case elfcpp::R_ARM_CALL:
8811 case elfcpp::R_ARM_JUMP24:
8812 case elfcpp::R_ARM_XPC25:
8813 gold_assert(gsym == NULL
8814 || gsym->has_plt_offset()
8815 || gsym->final_value_is_known()
8816 || (gsym->is_defined()
8817 && !gsym->is_from_dynobj()
8818 && !gsym->is_preemptible()));
8820 Arm_relocate_functions::arm_branch_common(
8821 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8822 thumb_bit, is_weakly_undefined_without_plt);
8825 case elfcpp::R_ARM_THM_JUMP19:
8827 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
8831 case elfcpp::R_ARM_THM_JUMP6:
8833 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
8836 case elfcpp::R_ARM_THM_JUMP8:
8838 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
8841 case elfcpp::R_ARM_THM_JUMP11:
8843 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
8846 case elfcpp::R_ARM_PREL31:
8847 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
8848 address, thumb_bit);
8851 case elfcpp::R_ARM_V4BX:
8852 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
8854 const bool is_v4bx_interworking =
8855 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
8857 Arm_relocate_functions::v4bx(relinfo, view, object, address,
8858 is_v4bx_interworking);
8862 case elfcpp::R_ARM_THM_PC8:
8864 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
8867 case elfcpp::R_ARM_THM_PC12:
8869 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
8872 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8874 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
8878 case elfcpp::R_ARM_ALU_PC_G0_NC:
8879 case elfcpp::R_ARM_ALU_PC_G0:
8880 case elfcpp::R_ARM_ALU_PC_G1_NC:
8881 case elfcpp::R_ARM_ALU_PC_G1:
8882 case elfcpp::R_ARM_ALU_PC_G2:
8883 case elfcpp::R_ARM_ALU_SB_G0_NC:
8884 case elfcpp::R_ARM_ALU_SB_G0:
8885 case elfcpp::R_ARM_ALU_SB_G1_NC:
8886 case elfcpp::R_ARM_ALU_SB_G1:
8887 case elfcpp::R_ARM_ALU_SB_G2:
8889 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
8890 reloc_property->group_index(),
8891 relative_address_base,
8892 thumb_bit, check_overflow);
8895 case elfcpp::R_ARM_LDR_PC_G0:
8896 case elfcpp::R_ARM_LDR_PC_G1:
8897 case elfcpp::R_ARM_LDR_PC_G2:
8898 case elfcpp::R_ARM_LDR_SB_G0:
8899 case elfcpp::R_ARM_LDR_SB_G1:
8900 case elfcpp::R_ARM_LDR_SB_G2:
8902 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
8903 reloc_property->group_index(),
8904 relative_address_base);
8907 case elfcpp::R_ARM_LDRS_PC_G0:
8908 case elfcpp::R_ARM_LDRS_PC_G1:
8909 case elfcpp::R_ARM_LDRS_PC_G2:
8910 case elfcpp::R_ARM_LDRS_SB_G0:
8911 case elfcpp::R_ARM_LDRS_SB_G1:
8912 case elfcpp::R_ARM_LDRS_SB_G2:
8914 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
8915 reloc_property->group_index(),
8916 relative_address_base);
8919 case elfcpp::R_ARM_LDC_PC_G0:
8920 case elfcpp::R_ARM_LDC_PC_G1:
8921 case elfcpp::R_ARM_LDC_PC_G2:
8922 case elfcpp::R_ARM_LDC_SB_G0:
8923 case elfcpp::R_ARM_LDC_SB_G1:
8924 case elfcpp::R_ARM_LDC_SB_G2:
8926 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
8927 reloc_property->group_index(),
8928 relative_address_base);
8931 // These are initial tls relocs, which are expected when
8933 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8934 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8935 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8936 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8937 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8939 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
8940 view, address, view_size);
8947 // Report any errors.
8948 switch (reloc_status)
8950 case Arm_relocate_functions::STATUS_OKAY:
8952 case Arm_relocate_functions::STATUS_OVERFLOW:
8953 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8954 _("relocation overflow in %s"),
8955 reloc_property->name().c_str());
8957 case Arm_relocate_functions::STATUS_BAD_RELOC:
8958 gold_error_at_location(
8962 _("unexpected opcode while processing relocation %s"),
8963 reloc_property->name().c_str());
8972 // Perform a TLS relocation.
8974 template<bool big_endian>
8975 inline typename Arm_relocate_functions<big_endian>::Status
8976 Target_arm<big_endian>::Relocate::relocate_tls(
8977 const Relocate_info<32, big_endian>* relinfo,
8978 Target_arm<big_endian>* target,
8980 const elfcpp::Rel<32, big_endian>& rel,
8981 unsigned int r_type,
8982 const Sized_symbol<32>* gsym,
8983 const Symbol_value<32>* psymval,
8984 unsigned char* view,
8985 elfcpp::Elf_types<32>::Elf_Addr address,
8986 section_size_type /*view_size*/ )
8988 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
8989 typedef Relocate_functions<32, big_endian> RelocFuncs;
8990 Output_segment* tls_segment = relinfo->layout->tls_segment();
8992 const Sized_relobj<32, big_endian>* object = relinfo->object;
8994 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
8996 const bool is_final = (gsym == NULL
8997 ? !parameters->options().shared()
8998 : gsym->final_value_is_known());
8999 const tls::Tls_optimization optimized_type
9000 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
9003 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
9005 unsigned int got_type = GOT_TYPE_TLS_PAIR;
9006 unsigned int got_offset;
9009 gold_assert(gsym->has_got_offset(got_type));
9010 got_offset = gsym->got_offset(got_type) - target->got_size();
9014 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9015 gold_assert(object->local_has_got_offset(r_sym, got_type));
9016 got_offset = (object->local_got_offset(r_sym, got_type)
9017 - target->got_size());
9019 if (optimized_type == tls::TLSOPT_NONE)
9021 Arm_address got_entry =
9022 target->got_plt_section()->address() + got_offset;
9024 // Relocate the field with the PC relative offset of the pair of
9026 RelocFuncs::pcrel32(view, got_entry, address);
9027 return ArmRelocFuncs::STATUS_OKAY;
9032 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
9033 if (optimized_type == tls::TLSOPT_NONE)
9035 // Relocate the field with the offset of the GOT entry for
9036 // the module index.
9037 unsigned int got_offset;
9038 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
9039 - target->got_size());
9040 Arm_address got_entry =
9041 target->got_plt_section()->address() + got_offset;
9043 // Relocate the field with the PC relative offset of the pair of
9045 RelocFuncs::pcrel32(view, got_entry, address);
9046 return ArmRelocFuncs::STATUS_OKAY;
9050 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
9051 RelocFuncs::rel32(view, value);
9052 return ArmRelocFuncs::STATUS_OKAY;
9054 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
9055 if (optimized_type == tls::TLSOPT_NONE)
9057 // Relocate the field with the offset of the GOT entry for
9058 // the tp-relative offset of the symbol.
9059 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
9060 unsigned int got_offset;
9063 gold_assert(gsym->has_got_offset(got_type));
9064 got_offset = gsym->got_offset(got_type);
9068 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9069 gold_assert(object->local_has_got_offset(r_sym, got_type));
9070 got_offset = object->local_got_offset(r_sym, got_type);
9073 // All GOT offsets are relative to the end of the GOT.
9074 got_offset -= target->got_size();
9076 Arm_address got_entry =
9077 target->got_plt_section()->address() + got_offset;
9079 // Relocate the field with the PC relative offset of the GOT entry.
9080 RelocFuncs::pcrel32(view, got_entry, address);
9081 return ArmRelocFuncs::STATUS_OKAY;
9085 case elfcpp::R_ARM_TLS_LE32: // Local-exec
9086 // If we're creating a shared library, a dynamic relocation will
9087 // have been created for this location, so do not apply it now.
9088 if (!parameters->options().shared())
9090 gold_assert(tls_segment != NULL);
9092 // $tp points to the TCB, which is followed by the TLS, so we
9093 // need to add TCB size to the offset.
9094 Arm_address aligned_tcb_size =
9095 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
9096 RelocFuncs::rel32(view, value + aligned_tcb_size);
9099 return ArmRelocFuncs::STATUS_OKAY;
9105 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
9106 _("unsupported reloc %u"),
9108 return ArmRelocFuncs::STATUS_BAD_RELOC;
9111 // Relocate section data.
9113 template<bool big_endian>
9115 Target_arm<big_endian>::relocate_section(
9116 const Relocate_info<32, big_endian>* relinfo,
9117 unsigned int sh_type,
9118 const unsigned char* prelocs,
9120 Output_section* output_section,
9121 bool needs_special_offset_handling,
9122 unsigned char* view,
9123 Arm_address address,
9124 section_size_type view_size,
9125 const Reloc_symbol_changes* reloc_symbol_changes)
9127 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
9128 gold_assert(sh_type == elfcpp::SHT_REL);
9130 // See if we are relocating a relaxed input section. If so, the view
9131 // covers the whole output section and we need to adjust accordingly.
9132 if (needs_special_offset_handling)
9134 const Output_relaxed_input_section* poris =
9135 output_section->find_relaxed_input_section(relinfo->object,
9136 relinfo->data_shndx);
9139 Arm_address section_address = poris->address();
9140 section_size_type section_size = poris->data_size();
9142 gold_assert((section_address >= address)
9143 && ((section_address + section_size)
9144 <= (address + view_size)));
9146 off_t offset = section_address - address;
9149 view_size = section_size;
9153 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
9160 needs_special_offset_handling,
9164 reloc_symbol_changes);
9167 // Return the size of a relocation while scanning during a relocatable
9170 template<bool big_endian>
9172 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
9173 unsigned int r_type,
9176 r_type = get_real_reloc_type(r_type);
9177 const Arm_reloc_property* arp =
9178 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9183 std::string reloc_name =
9184 arm_reloc_property_table->reloc_name_in_error_message(r_type);
9185 gold_error(_("%s: unexpected %s in object file"),
9186 object->name().c_str(), reloc_name.c_str());
9191 // Scan the relocs during a relocatable link.
9193 template<bool big_endian>
9195 Target_arm<big_endian>::scan_relocatable_relocs(
9196 Symbol_table* symtab,
9198 Sized_relobj<32, big_endian>* object,
9199 unsigned int data_shndx,
9200 unsigned int sh_type,
9201 const unsigned char* prelocs,
9203 Output_section* output_section,
9204 bool needs_special_offset_handling,
9205 size_t local_symbol_count,
9206 const unsigned char* plocal_symbols,
9207 Relocatable_relocs* rr)
9209 gold_assert(sh_type == elfcpp::SHT_REL);
9211 typedef Arm_scan_relocatable_relocs<big_endian, elfcpp::SHT_REL,
9212 Relocatable_size_for_reloc> Scan_relocatable_relocs;
9214 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
9215 Scan_relocatable_relocs>(
9223 needs_special_offset_handling,
9229 // Relocate a section during a relocatable link.
9231 template<bool big_endian>
9233 Target_arm<big_endian>::relocate_for_relocatable(
9234 const Relocate_info<32, big_endian>* relinfo,
9235 unsigned int sh_type,
9236 const unsigned char* prelocs,
9238 Output_section* output_section,
9239 off_t offset_in_output_section,
9240 const Relocatable_relocs* rr,
9241 unsigned char* view,
9242 Arm_address view_address,
9243 section_size_type view_size,
9244 unsigned char* reloc_view,
9245 section_size_type reloc_view_size)
9247 gold_assert(sh_type == elfcpp::SHT_REL);
9249 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
9254 offset_in_output_section,
9263 // Perform target-specific processing in a relocatable link. This is
9264 // only used if we use the relocation strategy RELOC_SPECIAL.
9266 template<bool big_endian>
9268 Target_arm<big_endian>::relocate_special_relocatable(
9269 const Relocate_info<32, big_endian>* relinfo,
9270 unsigned int sh_type,
9271 const unsigned char* preloc_in,
9273 Output_section* output_section,
9274 off_t offset_in_output_section,
9275 unsigned char* view,
9276 elfcpp::Elf_types<32>::Elf_Addr view_address,
9278 unsigned char* preloc_out)
9280 // We can only handle REL type relocation sections.
9281 gold_assert(sh_type == elfcpp::SHT_REL);
9283 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc Reltype;
9284 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc_write
9286 const Arm_address invalid_address = static_cast<Arm_address>(0) - 1;
9288 const Arm_relobj<big_endian>* object =
9289 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9290 const unsigned int local_count = object->local_symbol_count();
9292 Reltype reloc(preloc_in);
9293 Reltype_write reloc_write(preloc_out);
9295 elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
9296 const unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
9297 const unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
9299 const Arm_reloc_property* arp =
9300 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9301 gold_assert(arp != NULL);
9303 // Get the new symbol index.
9304 // We only use RELOC_SPECIAL strategy in local relocations.
9305 gold_assert(r_sym < local_count);
9307 // We are adjusting a section symbol. We need to find
9308 // the symbol table index of the section symbol for
9309 // the output section corresponding to input section
9310 // in which this symbol is defined.
9312 unsigned int shndx = object->local_symbol_input_shndx(r_sym, &is_ordinary);
9313 gold_assert(is_ordinary);
9314 Output_section* os = object->output_section(shndx);
9315 gold_assert(os != NULL);
9316 gold_assert(os->needs_symtab_index());
9317 unsigned int new_symndx = os->symtab_index();
9319 // Get the new offset--the location in the output section where
9320 // this relocation should be applied.
9322 Arm_address offset = reloc.get_r_offset();
9323 Arm_address new_offset;
9324 if (offset_in_output_section != invalid_address)
9325 new_offset = offset + offset_in_output_section;
9328 section_offset_type sot_offset =
9329 convert_types<section_offset_type, Arm_address>(offset);
9330 section_offset_type new_sot_offset =
9331 output_section->output_offset(object, relinfo->data_shndx,
9333 gold_assert(new_sot_offset != -1);
9334 new_offset = new_sot_offset;
9337 // In an object file, r_offset is an offset within the section.
9338 // In an executable or dynamic object, generated by
9339 // --emit-relocs, r_offset is an absolute address.
9340 if (!parameters->options().relocatable())
9342 new_offset += view_address;
9343 if (offset_in_output_section != invalid_address)
9344 new_offset -= offset_in_output_section;
9347 reloc_write.put_r_offset(new_offset);
9348 reloc_write.put_r_info(elfcpp::elf_r_info<32>(new_symndx, r_type));
9350 // Handle the reloc addend.
9351 // The relocation uses a section symbol in the input file.
9352 // We are adjusting it to use a section symbol in the output
9353 // file. The input section symbol refers to some address in
9354 // the input section. We need the relocation in the output
9355 // file to refer to that same address. This adjustment to
9356 // the addend is the same calculation we use for a simple
9357 // absolute relocation for the input section symbol.
9359 const Symbol_value<32>* psymval = object->local_symbol(r_sym);
9361 // Handle THUMB bit.
9362 Symbol_value<32> symval;
9363 Arm_address thumb_bit =
9364 object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
9366 && arp->uses_thumb_bit()
9367 && ((psymval->value(object, 0) & 1) != 0))
9369 Arm_address stripped_value =
9370 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
9371 symval.set_output_value(stripped_value);
9375 unsigned char* paddend = view + offset;
9376 typename Arm_relocate_functions<big_endian>::Status reloc_status =
9377 Arm_relocate_functions<big_endian>::STATUS_OKAY;
9380 case elfcpp::R_ARM_ABS8:
9381 reloc_status = Arm_relocate_functions<big_endian>::abs8(paddend, object,
9385 case elfcpp::R_ARM_ABS12:
9386 reloc_status = Arm_relocate_functions<big_endian>::abs12(paddend, object,
9390 case elfcpp::R_ARM_ABS16:
9391 reloc_status = Arm_relocate_functions<big_endian>::abs16(paddend, object,
9395 case elfcpp::R_ARM_THM_ABS5:
9396 reloc_status = Arm_relocate_functions<big_endian>::thm_abs5(paddend,
9401 case elfcpp::R_ARM_MOVW_ABS_NC:
9402 case elfcpp::R_ARM_MOVW_PREL_NC:
9403 case elfcpp::R_ARM_MOVW_BREL_NC:
9404 case elfcpp::R_ARM_MOVW_BREL:
9405 reloc_status = Arm_relocate_functions<big_endian>::movw(
9406 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9409 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
9410 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
9411 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
9412 case elfcpp::R_ARM_THM_MOVW_BREL:
9413 reloc_status = Arm_relocate_functions<big_endian>::thm_movw(
9414 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9417 case elfcpp::R_ARM_THM_CALL:
9418 case elfcpp::R_ARM_THM_XPC22:
9419 case elfcpp::R_ARM_THM_JUMP24:
9421 Arm_relocate_functions<big_endian>::thumb_branch_common(
9422 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9426 case elfcpp::R_ARM_PLT32:
9427 case elfcpp::R_ARM_CALL:
9428 case elfcpp::R_ARM_JUMP24:
9429 case elfcpp::R_ARM_XPC25:
9431 Arm_relocate_functions<big_endian>::arm_branch_common(
9432 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9436 case elfcpp::R_ARM_THM_JUMP19:
9438 Arm_relocate_functions<big_endian>::thm_jump19(paddend, object,
9439 psymval, 0, thumb_bit);
9442 case elfcpp::R_ARM_THM_JUMP6:
9444 Arm_relocate_functions<big_endian>::thm_jump6(paddend, object, psymval,
9448 case elfcpp::R_ARM_THM_JUMP8:
9450 Arm_relocate_functions<big_endian>::thm_jump8(paddend, object, psymval,
9454 case elfcpp::R_ARM_THM_JUMP11:
9456 Arm_relocate_functions<big_endian>::thm_jump11(paddend, object, psymval,
9460 case elfcpp::R_ARM_PREL31:
9462 Arm_relocate_functions<big_endian>::prel31(paddend, object, psymval, 0,
9466 case elfcpp::R_ARM_THM_PC8:
9468 Arm_relocate_functions<big_endian>::thm_pc8(paddend, object, psymval,
9472 case elfcpp::R_ARM_THM_PC12:
9474 Arm_relocate_functions<big_endian>::thm_pc12(paddend, object, psymval,
9478 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
9480 Arm_relocate_functions<big_endian>::thm_alu11(paddend, object, psymval,
9484 // These relocation truncate relocation results so we cannot handle them
9485 // in a relocatable link.
9486 case elfcpp::R_ARM_MOVT_ABS:
9487 case elfcpp::R_ARM_THM_MOVT_ABS:
9488 case elfcpp::R_ARM_MOVT_PREL:
9489 case elfcpp::R_ARM_MOVT_BREL:
9490 case elfcpp::R_ARM_THM_MOVT_PREL:
9491 case elfcpp::R_ARM_THM_MOVT_BREL:
9492 case elfcpp::R_ARM_ALU_PC_G0_NC:
9493 case elfcpp::R_ARM_ALU_PC_G0:
9494 case elfcpp::R_ARM_ALU_PC_G1_NC:
9495 case elfcpp::R_ARM_ALU_PC_G1:
9496 case elfcpp::R_ARM_ALU_PC_G2:
9497 case elfcpp::R_ARM_ALU_SB_G0_NC:
9498 case elfcpp::R_ARM_ALU_SB_G0:
9499 case elfcpp::R_ARM_ALU_SB_G1_NC:
9500 case elfcpp::R_ARM_ALU_SB_G1:
9501 case elfcpp::R_ARM_ALU_SB_G2:
9502 case elfcpp::R_ARM_LDR_PC_G0:
9503 case elfcpp::R_ARM_LDR_PC_G1:
9504 case elfcpp::R_ARM_LDR_PC_G2:
9505 case elfcpp::R_ARM_LDR_SB_G0:
9506 case elfcpp::R_ARM_LDR_SB_G1:
9507 case elfcpp::R_ARM_LDR_SB_G2:
9508 case elfcpp::R_ARM_LDRS_PC_G0:
9509 case elfcpp::R_ARM_LDRS_PC_G1:
9510 case elfcpp::R_ARM_LDRS_PC_G2:
9511 case elfcpp::R_ARM_LDRS_SB_G0:
9512 case elfcpp::R_ARM_LDRS_SB_G1:
9513 case elfcpp::R_ARM_LDRS_SB_G2:
9514 case elfcpp::R_ARM_LDC_PC_G0:
9515 case elfcpp::R_ARM_LDC_PC_G1:
9516 case elfcpp::R_ARM_LDC_PC_G2:
9517 case elfcpp::R_ARM_LDC_SB_G0:
9518 case elfcpp::R_ARM_LDC_SB_G1:
9519 case elfcpp::R_ARM_LDC_SB_G2:
9520 gold_error(_("cannot handle %s in a relocatable link"),
9521 arp->name().c_str());
9528 // Report any errors.
9529 switch (reloc_status)
9531 case Arm_relocate_functions<big_endian>::STATUS_OKAY:
9533 case Arm_relocate_functions<big_endian>::STATUS_OVERFLOW:
9534 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9535 _("relocation overflow in %s"),
9536 arp->name().c_str());
9538 case Arm_relocate_functions<big_endian>::STATUS_BAD_RELOC:
9539 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9540 _("unexpected opcode while processing relocation %s"),
9541 arp->name().c_str());
9548 // Return the value to use for a dynamic symbol which requires special
9549 // treatment. This is how we support equality comparisons of function
9550 // pointers across shared library boundaries, as described in the
9551 // processor specific ABI supplement.
9553 template<bool big_endian>
9555 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
9557 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
9558 return this->plt_section()->address() + gsym->plt_offset();
9561 // Map platform-specific relocs to real relocs
9563 template<bool big_endian>
9565 Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
9569 case elfcpp::R_ARM_TARGET1:
9570 // This is either R_ARM_ABS32 or R_ARM_REL32;
9571 return elfcpp::R_ARM_ABS32;
9573 case elfcpp::R_ARM_TARGET2:
9574 // This can be any reloc type but ususally is R_ARM_GOT_PREL
9575 return elfcpp::R_ARM_GOT_PREL;
9582 // Whether if two EABI versions V1 and V2 are compatible.
9584 template<bool big_endian>
9586 Target_arm<big_endian>::are_eabi_versions_compatible(
9587 elfcpp::Elf_Word v1,
9588 elfcpp::Elf_Word v2)
9590 // v4 and v5 are the same spec before and after it was released,
9591 // so allow mixing them.
9592 if ((v1 == elfcpp::EF_ARM_EABI_UNKNOWN || v2 == elfcpp::EF_ARM_EABI_UNKNOWN)
9593 || (v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
9594 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
9600 // Combine FLAGS from an input object called NAME and the processor-specific
9601 // flags in the ELF header of the output. Much of this is adapted from the
9602 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
9603 // in bfd/elf32-arm.c.
9605 template<bool big_endian>
9607 Target_arm<big_endian>::merge_processor_specific_flags(
9608 const std::string& name,
9609 elfcpp::Elf_Word flags)
9611 if (this->are_processor_specific_flags_set())
9613 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
9615 // Nothing to merge if flags equal to those in output.
9616 if (flags == out_flags)
9619 // Complain about various flag mismatches.
9620 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
9621 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
9622 if (!this->are_eabi_versions_compatible(version1, version2)
9623 && parameters->options().warn_mismatch())
9624 gold_error(_("Source object %s has EABI version %d but output has "
9625 "EABI version %d."),
9627 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
9628 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
9632 // If the input is the default architecture and had the default
9633 // flags then do not bother setting the flags for the output
9634 // architecture, instead allow future merges to do this. If no
9635 // future merges ever set these flags then they will retain their
9636 // uninitialised values, which surprise surprise, correspond
9637 // to the default values.
9641 // This is the first time, just copy the flags.
9642 // We only copy the EABI version for now.
9643 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
9647 // Adjust ELF file header.
9648 template<bool big_endian>
9650 Target_arm<big_endian>::do_adjust_elf_header(
9651 unsigned char* view,
9654 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
9656 elfcpp::Ehdr<32, big_endian> ehdr(view);
9657 unsigned char e_ident[elfcpp::EI_NIDENT];
9658 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
9660 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
9661 == elfcpp::EF_ARM_EABI_UNKNOWN)
9662 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
9664 e_ident[elfcpp::EI_OSABI] = 0;
9665 e_ident[elfcpp::EI_ABIVERSION] = 0;
9667 // FIXME: Do EF_ARM_BE8 adjustment.
9669 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
9670 oehdr.put_e_ident(e_ident);
9673 // do_make_elf_object to override the same function in the base class.
9674 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
9675 // to store ARM specific information. Hence we need to have our own
9676 // ELF object creation.
9678 template<bool big_endian>
9680 Target_arm<big_endian>::do_make_elf_object(
9681 const std::string& name,
9682 Input_file* input_file,
9683 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
9685 int et = ehdr.get_e_type();
9686 if (et == elfcpp::ET_REL)
9688 Arm_relobj<big_endian>* obj =
9689 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
9693 else if (et == elfcpp::ET_DYN)
9695 Sized_dynobj<32, big_endian>* obj =
9696 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
9702 gold_error(_("%s: unsupported ELF file type %d"),
9708 // Read the architecture from the Tag_also_compatible_with attribute, if any.
9709 // Returns -1 if no architecture could be read.
9710 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
9712 template<bool big_endian>
9714 Target_arm<big_endian>::get_secondary_compatible_arch(
9715 const Attributes_section_data* pasd)
9717 const Object_attribute *known_attributes =
9718 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9720 // Note: the tag and its argument below are uleb128 values, though
9721 // currently-defined values fit in one byte for each.
9722 const std::string& sv =
9723 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
9725 && sv.data()[0] == elfcpp::Tag_CPU_arch
9726 && (sv.data()[1] & 128) != 128)
9727 return sv.data()[1];
9729 // This tag is "safely ignorable", so don't complain if it looks funny.
9733 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
9734 // The tag is removed if ARCH is -1.
9735 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
9737 template<bool big_endian>
9739 Target_arm<big_endian>::set_secondary_compatible_arch(
9740 Attributes_section_data* pasd,
9743 Object_attribute *known_attributes =
9744 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9748 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
9752 // Note: the tag and its argument below are uleb128 values, though
9753 // currently-defined values fit in one byte for each.
9755 sv[0] = elfcpp::Tag_CPU_arch;
9756 gold_assert(arch != 0);
9760 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
9763 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
9765 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
9767 template<bool big_endian>
9769 Target_arm<big_endian>::tag_cpu_arch_combine(
9772 int* secondary_compat_out,
9774 int secondary_compat)
9776 #define T(X) elfcpp::TAG_CPU_ARCH_##X
9777 static const int v6t2[] =
9789 static const int v6k[] =
9802 static const int v7[] =
9816 static const int v6_m[] =
9831 static const int v6s_m[] =
9847 static const int v7e_m[] =
9864 static const int v4t_plus_v6_m[] =
9880 T(V4T_PLUS_V6_M) // V4T plus V6_M.
9882 static const int *comb[] =
9890 // Pseudo-architecture.
9894 // Check we've not got a higher architecture than we know about.
9896 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
9898 gold_error(_("%s: unknown CPU architecture"), name);
9902 // Override old tag if we have a Tag_also_compatible_with on the output.
9904 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
9905 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
9906 oldtag = T(V4T_PLUS_V6_M);
9908 // And override the new tag if we have a Tag_also_compatible_with on the
9911 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
9912 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
9913 newtag = T(V4T_PLUS_V6_M);
9915 // Architectures before V6KZ add features monotonically.
9916 int tagh = std::max(oldtag, newtag);
9917 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
9920 int tagl = std::min(oldtag, newtag);
9921 int result = comb[tagh - T(V6T2)][tagl];
9923 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
9924 // as the canonical version.
9925 if (result == T(V4T_PLUS_V6_M))
9928 *secondary_compat_out = T(V6_M);
9931 *secondary_compat_out = -1;
9935 gold_error(_("%s: conflicting CPU architectures %d/%d"),
9936 name, oldtag, newtag);
9944 // Helper to print AEABI enum tag value.
9946 template<bool big_endian>
9948 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
9950 static const char *aeabi_enum_names[] =
9951 { "", "variable-size", "32-bit", "" };
9952 const size_t aeabi_enum_names_size =
9953 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
9955 if (value < aeabi_enum_names_size)
9956 return std::string(aeabi_enum_names[value]);
9960 sprintf(buffer, "<unknown value %u>", value);
9961 return std::string(buffer);
9965 // Return the string value to store in TAG_CPU_name.
9967 template<bool big_endian>
9969 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
9971 static const char *name_table[] = {
9972 // These aren't real CPU names, but we can't guess
9973 // that from the architecture version alone.
9989 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
9991 if (value < name_table_size)
9992 return std::string(name_table[value]);
9996 sprintf(buffer, "<unknown CPU value %u>", value);
9997 return std::string(buffer);
10001 // Merge object attributes from input file called NAME with those of the
10002 // output. The input object attributes are in the object pointed by PASD.
10004 template<bool big_endian>
10006 Target_arm<big_endian>::merge_object_attributes(
10008 const Attributes_section_data* pasd)
10010 // Return if there is no attributes section data.
10014 // If output has no object attributes, just copy.
10015 const int vendor = Object_attribute::OBJ_ATTR_PROC;
10016 if (this->attributes_section_data_ == NULL)
10018 this->attributes_section_data_ = new Attributes_section_data(*pasd);
10019 Object_attribute* out_attr =
10020 this->attributes_section_data_->known_attributes(vendor);
10022 // We do not output objects with Tag_MPextension_use_legacy - we move
10023 // the attribute's value to Tag_MPextension_use. */
10024 if (out_attr[elfcpp::Tag_MPextension_use_legacy].int_value() != 0)
10026 if (out_attr[elfcpp::Tag_MPextension_use].int_value() != 0
10027 && out_attr[elfcpp::Tag_MPextension_use_legacy].int_value()
10028 != out_attr[elfcpp::Tag_MPextension_use].int_value())
10030 gold_error(_("%s has both the current and legacy "
10031 "Tag_MPextension_use attributes"),
10035 out_attr[elfcpp::Tag_MPextension_use] =
10036 out_attr[elfcpp::Tag_MPextension_use_legacy];
10037 out_attr[elfcpp::Tag_MPextension_use_legacy].set_type(0);
10038 out_attr[elfcpp::Tag_MPextension_use_legacy].set_int_value(0);
10044 const Object_attribute* in_attr = pasd->known_attributes(vendor);
10045 Object_attribute* out_attr =
10046 this->attributes_section_data_->known_attributes(vendor);
10048 // This needs to happen before Tag_ABI_FP_number_model is merged. */
10049 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
10050 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
10052 // Ignore mismatches if the object doesn't use floating point. */
10053 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
10054 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
10055 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
10056 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0
10057 && parameters->options().warn_mismatch())
10058 gold_error(_("%s uses VFP register arguments, output does not"),
10062 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
10064 // Merge this attribute with existing attributes.
10067 case elfcpp::Tag_CPU_raw_name:
10068 case elfcpp::Tag_CPU_name:
10069 // These are merged after Tag_CPU_arch.
10072 case elfcpp::Tag_ABI_optimization_goals:
10073 case elfcpp::Tag_ABI_FP_optimization_goals:
10074 // Use the first value seen.
10077 case elfcpp::Tag_CPU_arch:
10079 unsigned int saved_out_attr = out_attr->int_value();
10080 // Merge Tag_CPU_arch and Tag_also_compatible_with.
10081 int secondary_compat =
10082 this->get_secondary_compatible_arch(pasd);
10083 int secondary_compat_out =
10084 this->get_secondary_compatible_arch(
10085 this->attributes_section_data_);
10086 out_attr[i].set_int_value(
10087 tag_cpu_arch_combine(name, out_attr[i].int_value(),
10088 &secondary_compat_out,
10089 in_attr[i].int_value(),
10090 secondary_compat));
10091 this->set_secondary_compatible_arch(this->attributes_section_data_,
10092 secondary_compat_out);
10094 // Merge Tag_CPU_name and Tag_CPU_raw_name.
10095 if (out_attr[i].int_value() == saved_out_attr)
10096 ; // Leave the names alone.
10097 else if (out_attr[i].int_value() == in_attr[i].int_value())
10099 // The output architecture has been changed to match the
10100 // input architecture. Use the input names.
10101 out_attr[elfcpp::Tag_CPU_name].set_string_value(
10102 in_attr[elfcpp::Tag_CPU_name].string_value());
10103 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
10104 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
10108 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
10109 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
10112 // If we still don't have a value for Tag_CPU_name,
10113 // make one up now. Tag_CPU_raw_name remains blank.
10114 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
10116 const std::string cpu_name =
10117 this->tag_cpu_name_value(out_attr[i].int_value());
10118 // FIXME: If we see an unknown CPU, this will be set
10119 // to "<unknown CPU n>", where n is the attribute value.
10120 // This is different from BFD, which leaves the name alone.
10121 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
10126 case elfcpp::Tag_ARM_ISA_use:
10127 case elfcpp::Tag_THUMB_ISA_use:
10128 case elfcpp::Tag_WMMX_arch:
10129 case elfcpp::Tag_Advanced_SIMD_arch:
10130 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
10131 case elfcpp::Tag_ABI_FP_rounding:
10132 case elfcpp::Tag_ABI_FP_exceptions:
10133 case elfcpp::Tag_ABI_FP_user_exceptions:
10134 case elfcpp::Tag_ABI_FP_number_model:
10135 case elfcpp::Tag_VFP_HP_extension:
10136 case elfcpp::Tag_CPU_unaligned_access:
10137 case elfcpp::Tag_T2EE_use:
10138 case elfcpp::Tag_Virtualization_use:
10139 case elfcpp::Tag_MPextension_use:
10140 // Use the largest value specified.
10141 if (in_attr[i].int_value() > out_attr[i].int_value())
10142 out_attr[i].set_int_value(in_attr[i].int_value());
10145 case elfcpp::Tag_ABI_align8_preserved:
10146 case elfcpp::Tag_ABI_PCS_RO_data:
10147 // Use the smallest value specified.
10148 if (in_attr[i].int_value() < out_attr[i].int_value())
10149 out_attr[i].set_int_value(in_attr[i].int_value());
10152 case elfcpp::Tag_ABI_align8_needed:
10153 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
10154 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
10155 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
10158 // This error message should be enabled once all non-conformant
10159 // binaries in the toolchain have had the attributes set
10161 // gold_error(_("output 8-byte data alignment conflicts with %s"),
10165 case elfcpp::Tag_ABI_FP_denormal:
10166 case elfcpp::Tag_ABI_PCS_GOT_use:
10168 // These tags have 0 = don't care, 1 = strong requirement,
10169 // 2 = weak requirement.
10170 static const int order_021[3] = {0, 2, 1};
10172 // Use the "greatest" from the sequence 0, 2, 1, or the largest
10173 // value if greater than 2 (for future-proofing).
10174 if ((in_attr[i].int_value() > 2
10175 && in_attr[i].int_value() > out_attr[i].int_value())
10176 || (in_attr[i].int_value() <= 2
10177 && out_attr[i].int_value() <= 2
10178 && (order_021[in_attr[i].int_value()]
10179 > order_021[out_attr[i].int_value()])))
10180 out_attr[i].set_int_value(in_attr[i].int_value());
10184 case elfcpp::Tag_CPU_arch_profile:
10185 if (out_attr[i].int_value() != in_attr[i].int_value())
10187 // 0 will merge with anything.
10188 // 'A' and 'S' merge to 'A'.
10189 // 'R' and 'S' merge to 'R'.
10190 // 'M' and 'A|R|S' is an error.
10191 if (out_attr[i].int_value() == 0
10192 || (out_attr[i].int_value() == 'S'
10193 && (in_attr[i].int_value() == 'A'
10194 || in_attr[i].int_value() == 'R')))
10195 out_attr[i].set_int_value(in_attr[i].int_value());
10196 else if (in_attr[i].int_value() == 0
10197 || (in_attr[i].int_value() == 'S'
10198 && (out_attr[i].int_value() == 'A'
10199 || out_attr[i].int_value() == 'R')))
10201 else if (parameters->options().warn_mismatch())
10204 (_("conflicting architecture profiles %c/%c"),
10205 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
10206 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
10210 case elfcpp::Tag_VFP_arch:
10212 static const struct
10216 } vfp_versions[7] =
10227 // Values greater than 6 aren't defined, so just pick the
10229 if (in_attr[i].int_value() > 6
10230 && in_attr[i].int_value() > out_attr[i].int_value())
10232 *out_attr = *in_attr;
10235 // The output uses the superset of input features
10236 // (ISA version) and registers.
10237 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
10238 vfp_versions[out_attr[i].int_value()].ver);
10239 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
10240 vfp_versions[out_attr[i].int_value()].regs);
10241 // This assumes all possible supersets are also a valid
10244 for (newval = 6; newval > 0; newval--)
10246 if (regs == vfp_versions[newval].regs
10247 && ver == vfp_versions[newval].ver)
10250 out_attr[i].set_int_value(newval);
10253 case elfcpp::Tag_PCS_config:
10254 if (out_attr[i].int_value() == 0)
10255 out_attr[i].set_int_value(in_attr[i].int_value());
10256 else if (in_attr[i].int_value() != 0
10257 && out_attr[i].int_value() != 0
10258 && parameters->options().warn_mismatch())
10260 // It's sometimes ok to mix different configs, so this is only
10262 gold_warning(_("%s: conflicting platform configuration"), name);
10265 case elfcpp::Tag_ABI_PCS_R9_use:
10266 if (in_attr[i].int_value() != out_attr[i].int_value()
10267 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
10268 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused
10269 && parameters->options().warn_mismatch())
10271 gold_error(_("%s: conflicting use of R9"), name);
10273 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
10274 out_attr[i].set_int_value(in_attr[i].int_value());
10276 case elfcpp::Tag_ABI_PCS_RW_data:
10277 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
10278 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10279 != elfcpp::AEABI_R9_SB)
10280 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10281 != elfcpp::AEABI_R9_unused)
10282 && parameters->options().warn_mismatch())
10284 gold_error(_("%s: SB relative addressing conflicts with use "
10288 // Use the smallest value specified.
10289 if (in_attr[i].int_value() < out_attr[i].int_value())
10290 out_attr[i].set_int_value(in_attr[i].int_value());
10292 case elfcpp::Tag_ABI_PCS_wchar_t:
10293 if (out_attr[i].int_value()
10294 && in_attr[i].int_value()
10295 && out_attr[i].int_value() != in_attr[i].int_value()
10296 && parameters->options().warn_mismatch()
10297 && parameters->options().wchar_size_warning())
10299 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
10300 "use %u-byte wchar_t; use of wchar_t values "
10301 "across objects may fail"),
10302 name, in_attr[i].int_value(),
10303 out_attr[i].int_value());
10305 else if (in_attr[i].int_value() && !out_attr[i].int_value())
10306 out_attr[i].set_int_value(in_attr[i].int_value());
10308 case elfcpp::Tag_ABI_enum_size:
10309 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
10311 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
10312 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
10314 // The existing object is compatible with anything.
10315 // Use whatever requirements the new object has.
10316 out_attr[i].set_int_value(in_attr[i].int_value());
10318 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
10319 && out_attr[i].int_value() != in_attr[i].int_value()
10320 && parameters->options().warn_mismatch()
10321 && parameters->options().enum_size_warning())
10323 unsigned int in_value = in_attr[i].int_value();
10324 unsigned int out_value = out_attr[i].int_value();
10325 gold_warning(_("%s uses %s enums yet the output is to use "
10326 "%s enums; use of enum values across objects "
10329 this->aeabi_enum_name(in_value).c_str(),
10330 this->aeabi_enum_name(out_value).c_str());
10334 case elfcpp::Tag_ABI_VFP_args:
10337 case elfcpp::Tag_ABI_WMMX_args:
10338 if (in_attr[i].int_value() != out_attr[i].int_value()
10339 && parameters->options().warn_mismatch())
10341 gold_error(_("%s uses iWMMXt register arguments, output does "
10346 case Object_attribute::Tag_compatibility:
10347 // Merged in target-independent code.
10349 case elfcpp::Tag_ABI_HardFP_use:
10350 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
10351 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
10352 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
10353 out_attr[i].set_int_value(3);
10354 else if (in_attr[i].int_value() > out_attr[i].int_value())
10355 out_attr[i].set_int_value(in_attr[i].int_value());
10357 case elfcpp::Tag_ABI_FP_16bit_format:
10358 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
10360 if (in_attr[i].int_value() != out_attr[i].int_value()
10361 && parameters->options().warn_mismatch())
10362 gold_error(_("fp16 format mismatch between %s and output"),
10365 if (in_attr[i].int_value() != 0)
10366 out_attr[i].set_int_value(in_attr[i].int_value());
10369 case elfcpp::Tag_DIV_use:
10370 // This tag is set to zero if we can use UDIV and SDIV in Thumb
10371 // mode on a v7-M or v7-R CPU; to one if we can not use UDIV or
10372 // SDIV at all; and to two if we can use UDIV or SDIV on a v7-A
10373 // CPU. We will merge as follows: If the input attribute's value
10374 // is one then the output attribute's value remains unchanged. If
10375 // the input attribute's value is zero or two then if the output
10376 // attribute's value is one the output value is set to the input
10377 // value, otherwise the output value must be the same as the
10379 if (in_attr[i].int_value() != 1 && out_attr[i].int_value() != 1)
10381 if (in_attr[i].int_value() != out_attr[i].int_value())
10383 gold_error(_("DIV usage mismatch between %s and output"),
10388 if (in_attr[i].int_value() != 1)
10389 out_attr[i].set_int_value(in_attr[i].int_value());
10393 case elfcpp::Tag_MPextension_use_legacy:
10394 // We don't output objects with Tag_MPextension_use_legacy - we
10395 // move the value to Tag_MPextension_use.
10396 if (in_attr[i].int_value() != 0
10397 && in_attr[elfcpp::Tag_MPextension_use].int_value() != 0)
10399 if (in_attr[elfcpp::Tag_MPextension_use].int_value()
10400 != in_attr[i].int_value())
10402 gold_error(_("%s has has both the current and legacy "
10403 "Tag_MPextension_use attributes"),
10408 if (in_attr[i].int_value()
10409 > out_attr[elfcpp::Tag_MPextension_use].int_value())
10410 out_attr[elfcpp::Tag_MPextension_use] = in_attr[i];
10414 case elfcpp::Tag_nodefaults:
10415 // This tag is set if it exists, but the value is unused (and is
10416 // typically zero). We don't actually need to do anything here -
10417 // the merge happens automatically when the type flags are merged
10420 case elfcpp::Tag_also_compatible_with:
10421 // Already done in Tag_CPU_arch.
10423 case elfcpp::Tag_conformance:
10424 // Keep the attribute if it matches. Throw it away otherwise.
10425 // No attribute means no claim to conform.
10426 if (in_attr[i].string_value() != out_attr[i].string_value())
10427 out_attr[i].set_string_value("");
10432 const char* err_object = NULL;
10434 // The "known_obj_attributes" table does contain some undefined
10435 // attributes. Ensure that there are unused.
10436 if (out_attr[i].int_value() != 0
10437 || out_attr[i].string_value() != "")
10438 err_object = "output";
10439 else if (in_attr[i].int_value() != 0
10440 || in_attr[i].string_value() != "")
10443 if (err_object != NULL
10444 && parameters->options().warn_mismatch())
10446 // Attribute numbers >=64 (mod 128) can be safely ignored.
10447 if ((i & 127) < 64)
10448 gold_error(_("%s: unknown mandatory EABI object attribute "
10452 gold_warning(_("%s: unknown EABI object attribute %d"),
10456 // Only pass on attributes that match in both inputs.
10457 if (!in_attr[i].matches(out_attr[i]))
10459 out_attr[i].set_int_value(0);
10460 out_attr[i].set_string_value("");
10465 // If out_attr was copied from in_attr then it won't have a type yet.
10466 if (in_attr[i].type() && !out_attr[i].type())
10467 out_attr[i].set_type(in_attr[i].type());
10470 // Merge Tag_compatibility attributes and any common GNU ones.
10471 this->attributes_section_data_->merge(name, pasd);
10473 // Check for any attributes not known on ARM.
10474 typedef Vendor_object_attributes::Other_attributes Other_attributes;
10475 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
10476 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
10477 Other_attributes* out_other_attributes =
10478 this->attributes_section_data_->other_attributes(vendor);
10479 Other_attributes::iterator out_iter = out_other_attributes->begin();
10481 while (in_iter != in_other_attributes->end()
10482 || out_iter != out_other_attributes->end())
10484 const char* err_object = NULL;
10487 // The tags for each list are in numerical order.
10488 // If the tags are equal, then merge.
10489 if (out_iter != out_other_attributes->end()
10490 && (in_iter == in_other_attributes->end()
10491 || in_iter->first > out_iter->first))
10493 // This attribute only exists in output. We can't merge, and we
10494 // don't know what the tag means, so delete it.
10495 err_object = "output";
10496 err_tag = out_iter->first;
10497 int saved_tag = out_iter->first;
10498 delete out_iter->second;
10499 out_other_attributes->erase(out_iter);
10500 out_iter = out_other_attributes->upper_bound(saved_tag);
10502 else if (in_iter != in_other_attributes->end()
10503 && (out_iter != out_other_attributes->end()
10504 || in_iter->first < out_iter->first))
10506 // This attribute only exists in input. We can't merge, and we
10507 // don't know what the tag means, so ignore it.
10509 err_tag = in_iter->first;
10512 else // The tags are equal.
10514 // As present, all attributes in the list are unknown, and
10515 // therefore can't be merged meaningfully.
10516 err_object = "output";
10517 err_tag = out_iter->first;
10519 // Only pass on attributes that match in both inputs.
10520 if (!in_iter->second->matches(*(out_iter->second)))
10522 // No match. Delete the attribute.
10523 int saved_tag = out_iter->first;
10524 delete out_iter->second;
10525 out_other_attributes->erase(out_iter);
10526 out_iter = out_other_attributes->upper_bound(saved_tag);
10530 // Matched. Keep the attribute and move to the next.
10536 if (err_object && parameters->options().warn_mismatch())
10538 // Attribute numbers >=64 (mod 128) can be safely ignored. */
10539 if ((err_tag & 127) < 64)
10541 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
10542 err_object, err_tag);
10546 gold_warning(_("%s: unknown EABI object attribute %d"),
10547 err_object, err_tag);
10553 // Stub-generation methods for Target_arm.
10555 // Make a new Arm_input_section object.
10557 template<bool big_endian>
10558 Arm_input_section<big_endian>*
10559 Target_arm<big_endian>::new_arm_input_section(
10561 unsigned int shndx)
10563 Section_id sid(relobj, shndx);
10565 Arm_input_section<big_endian>* arm_input_section =
10566 new Arm_input_section<big_endian>(relobj, shndx);
10567 arm_input_section->init();
10569 // Register new Arm_input_section in map for look-up.
10570 std::pair<typename Arm_input_section_map::iterator, bool> ins =
10571 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
10573 // Make sure that it we have not created another Arm_input_section
10574 // for this input section already.
10575 gold_assert(ins.second);
10577 return arm_input_section;
10580 // Find the Arm_input_section object corresponding to the SHNDX-th input
10581 // section of RELOBJ.
10583 template<bool big_endian>
10584 Arm_input_section<big_endian>*
10585 Target_arm<big_endian>::find_arm_input_section(
10587 unsigned int shndx) const
10589 Section_id sid(relobj, shndx);
10590 typename Arm_input_section_map::const_iterator p =
10591 this->arm_input_section_map_.find(sid);
10592 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
10595 // Make a new stub table.
10597 template<bool big_endian>
10598 Stub_table<big_endian>*
10599 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
10601 Stub_table<big_endian>* stub_table =
10602 new Stub_table<big_endian>(owner);
10603 this->stub_tables_.push_back(stub_table);
10605 stub_table->set_address(owner->address() + owner->data_size());
10606 stub_table->set_file_offset(owner->offset() + owner->data_size());
10607 stub_table->finalize_data_size();
10612 // Scan a relocation for stub generation.
10614 template<bool big_endian>
10616 Target_arm<big_endian>::scan_reloc_for_stub(
10617 const Relocate_info<32, big_endian>* relinfo,
10618 unsigned int r_type,
10619 const Sized_symbol<32>* gsym,
10620 unsigned int r_sym,
10621 const Symbol_value<32>* psymval,
10622 elfcpp::Elf_types<32>::Elf_Swxword addend,
10623 Arm_address address)
10625 typedef typename Target_arm<big_endian>::Relocate Relocate;
10627 const Arm_relobj<big_endian>* arm_relobj =
10628 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10630 bool target_is_thumb;
10631 Symbol_value<32> symval;
10634 // This is a global symbol. Determine if we use PLT and if the
10635 // final target is THUMB.
10636 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
10638 // This uses a PLT, change the symbol value.
10639 symval.set_output_value(this->plt_section()->address()
10640 + gsym->plt_offset());
10642 target_is_thumb = false;
10644 else if (gsym->is_undefined())
10645 // There is no need to generate a stub symbol is undefined.
10650 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
10651 || (gsym->type() == elfcpp::STT_FUNC
10652 && !gsym->is_undefined()
10653 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
10658 // This is a local symbol. Determine if the final target is THUMB.
10659 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
10662 // Strip LSB if this points to a THUMB target.
10663 const Arm_reloc_property* reloc_property =
10664 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
10665 gold_assert(reloc_property != NULL);
10666 if (target_is_thumb
10667 && reloc_property->uses_thumb_bit()
10668 && ((psymval->value(arm_relobj, 0) & 1) != 0))
10670 Arm_address stripped_value =
10671 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
10672 symval.set_output_value(stripped_value);
10676 // Get the symbol value.
10677 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
10679 // Owing to pipelining, the PC relative branches below actually skip
10680 // two instructions when the branch offset is 0.
10681 Arm_address destination;
10684 case elfcpp::R_ARM_CALL:
10685 case elfcpp::R_ARM_JUMP24:
10686 case elfcpp::R_ARM_PLT32:
10688 destination = value + addend + 8;
10690 case elfcpp::R_ARM_THM_CALL:
10691 case elfcpp::R_ARM_THM_XPC22:
10692 case elfcpp::R_ARM_THM_JUMP24:
10693 case elfcpp::R_ARM_THM_JUMP19:
10695 destination = value + addend + 4;
10698 gold_unreachable();
10701 Reloc_stub* stub = NULL;
10702 Stub_type stub_type =
10703 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
10705 if (stub_type != arm_stub_none)
10707 // Try looking up an existing stub from a stub table.
10708 Stub_table<big_endian>* stub_table =
10709 arm_relobj->stub_table(relinfo->data_shndx);
10710 gold_assert(stub_table != NULL);
10712 // Locate stub by destination.
10713 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
10715 // Create a stub if there is not one already
10716 stub = stub_table->find_reloc_stub(stub_key);
10719 // create a new stub and add it to stub table.
10720 stub = this->stub_factory().make_reloc_stub(stub_type);
10721 stub_table->add_reloc_stub(stub, stub_key);
10724 // Record the destination address.
10725 stub->set_destination_address(destination
10726 | (target_is_thumb ? 1 : 0));
10729 // For Cortex-A8, we need to record a relocation at 4K page boundary.
10730 if (this->fix_cortex_a8_
10731 && (r_type == elfcpp::R_ARM_THM_JUMP24
10732 || r_type == elfcpp::R_ARM_THM_JUMP19
10733 || r_type == elfcpp::R_ARM_THM_CALL
10734 || r_type == elfcpp::R_ARM_THM_XPC22)
10735 && (address & 0xfffU) == 0xffeU)
10737 // Found a candidate. Note we haven't checked the destination is
10738 // within 4K here: if we do so (and don't create a record) we can't
10739 // tell that a branch should have been relocated when scanning later.
10740 this->cortex_a8_relocs_info_[address] =
10741 new Cortex_a8_reloc(stub, r_type,
10742 destination | (target_is_thumb ? 1 : 0));
10746 // This function scans a relocation sections for stub generation.
10747 // The template parameter Relocate must be a class type which provides
10748 // a single function, relocate(), which implements the machine
10749 // specific part of a relocation.
10751 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
10752 // SHT_REL or SHT_RELA.
10754 // PRELOCS points to the relocation data. RELOC_COUNT is the number
10755 // of relocs. OUTPUT_SECTION is the output section.
10756 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
10757 // mapped to output offsets.
10759 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
10760 // VIEW_SIZE is the size. These refer to the input section, unless
10761 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
10762 // the output section.
10764 template<bool big_endian>
10765 template<int sh_type>
10767 Target_arm<big_endian>::scan_reloc_section_for_stubs(
10768 const Relocate_info<32, big_endian>* relinfo,
10769 const unsigned char* prelocs,
10770 size_t reloc_count,
10771 Output_section* output_section,
10772 bool needs_special_offset_handling,
10773 const unsigned char* view,
10774 elfcpp::Elf_types<32>::Elf_Addr view_address,
10777 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
10778 const int reloc_size =
10779 Reloc_types<sh_type, 32, big_endian>::reloc_size;
10781 Arm_relobj<big_endian>* arm_object =
10782 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10783 unsigned int local_count = arm_object->local_symbol_count();
10785 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
10787 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
10789 Reltype reloc(prelocs);
10791 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
10792 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
10793 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
10795 r_type = this->get_real_reloc_type(r_type);
10797 // Only a few relocation types need stubs.
10798 if ((r_type != elfcpp::R_ARM_CALL)
10799 && (r_type != elfcpp::R_ARM_JUMP24)
10800 && (r_type != elfcpp::R_ARM_PLT32)
10801 && (r_type != elfcpp::R_ARM_THM_CALL)
10802 && (r_type != elfcpp::R_ARM_THM_XPC22)
10803 && (r_type != elfcpp::R_ARM_THM_JUMP24)
10804 && (r_type != elfcpp::R_ARM_THM_JUMP19)
10805 && (r_type != elfcpp::R_ARM_V4BX))
10808 section_offset_type offset =
10809 convert_to_section_size_type(reloc.get_r_offset());
10811 if (needs_special_offset_handling)
10813 offset = output_section->output_offset(relinfo->object,
10814 relinfo->data_shndx,
10820 // Create a v4bx stub if --fix-v4bx-interworking is used.
10821 if (r_type == elfcpp::R_ARM_V4BX)
10823 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
10825 // Get the BX instruction.
10826 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
10827 const Valtype* wv =
10828 reinterpret_cast<const Valtype*>(view + offset);
10829 elfcpp::Elf_types<32>::Elf_Swxword insn =
10830 elfcpp::Swap<32, big_endian>::readval(wv);
10831 const uint32_t reg = (insn & 0xf);
10835 // Try looking up an existing stub from a stub table.
10836 Stub_table<big_endian>* stub_table =
10837 arm_object->stub_table(relinfo->data_shndx);
10838 gold_assert(stub_table != NULL);
10840 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
10842 // create a new stub and add it to stub table.
10843 Arm_v4bx_stub* stub =
10844 this->stub_factory().make_arm_v4bx_stub(reg);
10845 gold_assert(stub != NULL);
10846 stub_table->add_arm_v4bx_stub(stub);
10854 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
10855 elfcpp::Elf_types<32>::Elf_Swxword addend =
10856 stub_addend_reader(r_type, view + offset, reloc);
10858 const Sized_symbol<32>* sym;
10860 Symbol_value<32> symval;
10861 const Symbol_value<32> *psymval;
10862 if (r_sym < local_count)
10865 psymval = arm_object->local_symbol(r_sym);
10867 // If the local symbol belongs to a section we are discarding,
10868 // and that section is a debug section, try to find the
10869 // corresponding kept section and map this symbol to its
10870 // counterpart in the kept section. The symbol must not
10871 // correspond to a section we are folding.
10873 unsigned int shndx = psymval->input_shndx(&is_ordinary);
10875 && shndx != elfcpp::SHN_UNDEF
10876 && !arm_object->is_section_included(shndx)
10877 && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
10879 if (comdat_behavior == CB_UNDETERMINED)
10882 arm_object->section_name(relinfo->data_shndx);
10883 comdat_behavior = get_comdat_behavior(name.c_str());
10885 if (comdat_behavior == CB_PRETEND)
10888 typename elfcpp::Elf_types<32>::Elf_Addr value =
10889 arm_object->map_to_kept_section(shndx, &found);
10891 symval.set_output_value(value + psymval->input_value());
10893 symval.set_output_value(0);
10897 symval.set_output_value(0);
10899 symval.set_no_output_symtab_entry();
10905 const Symbol* gsym = arm_object->global_symbol(r_sym);
10906 gold_assert(gsym != NULL);
10907 if (gsym->is_forwarder())
10908 gsym = relinfo->symtab->resolve_forwards(gsym);
10910 sym = static_cast<const Sized_symbol<32>*>(gsym);
10911 if (sym->has_symtab_index())
10912 symval.set_output_symtab_index(sym->symtab_index());
10914 symval.set_no_output_symtab_entry();
10916 // We need to compute the would-be final value of this global
10918 const Symbol_table* symtab = relinfo->symtab;
10919 const Sized_symbol<32>* sized_symbol =
10920 symtab->get_sized_symbol<32>(gsym);
10921 Symbol_table::Compute_final_value_status status;
10922 Arm_address value =
10923 symtab->compute_final_value<32>(sized_symbol, &status);
10925 // Skip this if the symbol has not output section.
10926 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
10929 symval.set_output_value(value);
10933 // If symbol is a section symbol, we don't know the actual type of
10934 // destination. Give up.
10935 if (psymval->is_section_symbol())
10938 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
10939 addend, view_address + offset);
10943 // Scan an input section for stub generation.
10945 template<bool big_endian>
10947 Target_arm<big_endian>::scan_section_for_stubs(
10948 const Relocate_info<32, big_endian>* relinfo,
10949 unsigned int sh_type,
10950 const unsigned char* prelocs,
10951 size_t reloc_count,
10952 Output_section* output_section,
10953 bool needs_special_offset_handling,
10954 const unsigned char* view,
10955 Arm_address view_address,
10956 section_size_type view_size)
10958 if (sh_type == elfcpp::SHT_REL)
10959 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
10964 needs_special_offset_handling,
10968 else if (sh_type == elfcpp::SHT_RELA)
10969 // We do not support RELA type relocations yet. This is provided for
10971 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
10976 needs_special_offset_handling,
10981 gold_unreachable();
10984 // Group input sections for stub generation.
10986 // We goup input sections in an output sections so that the total size,
10987 // including any padding space due to alignment is smaller than GROUP_SIZE
10988 // unless the only input section in group is bigger than GROUP_SIZE already.
10989 // Then an ARM stub table is created to follow the last input section
10990 // in group. For each group an ARM stub table is created an is placed
10991 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
10992 // extend the group after the stub table.
10994 template<bool big_endian>
10996 Target_arm<big_endian>::group_sections(
10998 section_size_type group_size,
10999 bool stubs_always_after_branch)
11001 // Group input sections and insert stub table
11002 Layout::Section_list section_list;
11003 layout->get_allocated_sections(§ion_list);
11004 for (Layout::Section_list::const_iterator p = section_list.begin();
11005 p != section_list.end();
11008 Arm_output_section<big_endian>* output_section =
11009 Arm_output_section<big_endian>::as_arm_output_section(*p);
11010 output_section->group_sections(group_size, stubs_always_after_branch,
11015 // Relaxation hook. This is where we do stub generation.
11017 template<bool big_endian>
11019 Target_arm<big_endian>::do_relax(
11021 const Input_objects* input_objects,
11022 Symbol_table* symtab,
11025 // No need to generate stubs if this is a relocatable link.
11026 gold_assert(!parameters->options().relocatable());
11028 // If this is the first pass, we need to group input sections into
11030 bool done_exidx_fixup = false;
11031 typedef typename Stub_table_list::iterator Stub_table_iterator;
11034 // Determine the stub group size. The group size is the absolute
11035 // value of the parameter --stub-group-size. If --stub-group-size
11036 // is passed a negative value, we restict stubs to be always after
11037 // the stubbed branches.
11038 int32_t stub_group_size_param =
11039 parameters->options().stub_group_size();
11040 bool stubs_always_after_branch = stub_group_size_param < 0;
11041 section_size_type stub_group_size = abs(stub_group_size_param);
11043 if (stub_group_size == 1)
11046 // Thumb branch range is +-4MB has to be used as the default
11047 // maximum size (a given section can contain both ARM and Thumb
11048 // code, so the worst case has to be taken into account). If we are
11049 // fixing cortex-a8 errata, the branch range has to be even smaller,
11050 // since wide conditional branch has a range of +-1MB only.
11052 // This value is 48K less than that, which allows for 4096
11053 // 12-byte stubs. If we exceed that, then we will fail to link.
11054 // The user will have to relink with an explicit group size
11056 stub_group_size = 4145152;
11059 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
11060 // page as the first half of a 32-bit branch straddling two 4K pages.
11061 // This is a crude way of enforcing that. In addition, long conditional
11062 // branches of THUMB-2 have a range of +-1M. If we are fixing cortex-A8
11063 // erratum, limit the group size to (1M - 12k) to avoid unreachable
11064 // cortex-A8 stubs from long conditional branches.
11065 if (this->fix_cortex_a8_)
11067 stubs_always_after_branch = true;
11068 const section_size_type cortex_a8_group_size = 1024 * (1024 - 12);
11069 stub_group_size = std::max(stub_group_size, cortex_a8_group_size);
11072 group_sections(layout, stub_group_size, stubs_always_after_branch);
11074 // Also fix .ARM.exidx section coverage.
11075 Arm_output_section<big_endian>* exidx_output_section = NULL;
11076 for (Layout::Section_list::const_iterator p =
11077 layout->section_list().begin();
11078 p != layout->section_list().end();
11080 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
11082 if (exidx_output_section == NULL)
11083 exidx_output_section =
11084 Arm_output_section<big_endian>::as_arm_output_section(*p);
11086 // We cannot handle this now.
11087 gold_error(_("multiple SHT_ARM_EXIDX sections %s and %s in a "
11088 "non-relocatable link"),
11089 exidx_output_section->name(),
11093 if (exidx_output_section != NULL)
11095 this->fix_exidx_coverage(layout, input_objects, exidx_output_section,
11097 done_exidx_fixup = true;
11102 // If this is not the first pass, addresses and file offsets have
11103 // been reset at this point, set them here.
11104 for (Stub_table_iterator sp = this->stub_tables_.begin();
11105 sp != this->stub_tables_.end();
11108 Arm_input_section<big_endian>* owner = (*sp)->owner();
11109 off_t off = align_address(owner->original_size(),
11110 (*sp)->addralign());
11111 (*sp)->set_address_and_file_offset(owner->address() + off,
11112 owner->offset() + off);
11116 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
11117 // beginning of each relaxation pass, just blow away all the stubs.
11118 // Alternatively, we could selectively remove only the stubs and reloc
11119 // information for code sections that have moved since the last pass.
11120 // That would require more book-keeping.
11121 if (this->fix_cortex_a8_)
11123 // Clear all Cortex-A8 reloc information.
11124 for (typename Cortex_a8_relocs_info::const_iterator p =
11125 this->cortex_a8_relocs_info_.begin();
11126 p != this->cortex_a8_relocs_info_.end();
11129 this->cortex_a8_relocs_info_.clear();
11131 // Remove all Cortex-A8 stubs.
11132 for (Stub_table_iterator sp = this->stub_tables_.begin();
11133 sp != this->stub_tables_.end();
11135 (*sp)->remove_all_cortex_a8_stubs();
11138 // Scan relocs for relocation stubs
11139 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11140 op != input_objects->relobj_end();
11143 Arm_relobj<big_endian>* arm_relobj =
11144 Arm_relobj<big_endian>::as_arm_relobj(*op);
11145 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
11148 // Check all stub tables to see if any of them have their data sizes
11149 // or addresses alignments changed. These are the only things that
11151 bool any_stub_table_changed = false;
11152 Unordered_set<const Output_section*> sections_needing_adjustment;
11153 for (Stub_table_iterator sp = this->stub_tables_.begin();
11154 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11157 if ((*sp)->update_data_size_and_addralign())
11159 // Update data size of stub table owner.
11160 Arm_input_section<big_endian>* owner = (*sp)->owner();
11161 uint64_t address = owner->address();
11162 off_t offset = owner->offset();
11163 owner->reset_address_and_file_offset();
11164 owner->set_address_and_file_offset(address, offset);
11166 sections_needing_adjustment.insert(owner->output_section());
11167 any_stub_table_changed = true;
11171 // Output_section_data::output_section() returns a const pointer but we
11172 // need to update output sections, so we record all output sections needing
11173 // update above and scan the sections here to find out what sections need
11175 for(Layout::Section_list::const_iterator p = layout->section_list().begin();
11176 p != layout->section_list().end();
11179 if (sections_needing_adjustment.find(*p)
11180 != sections_needing_adjustment.end())
11181 (*p)->set_section_offsets_need_adjustment();
11184 // Stop relaxation if no EXIDX fix-up and no stub table change.
11185 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
11187 // Finalize the stubs in the last relaxation pass.
11188 if (!continue_relaxation)
11190 for (Stub_table_iterator sp = this->stub_tables_.begin();
11191 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11193 (*sp)->finalize_stubs();
11195 // Update output local symbol counts of objects if necessary.
11196 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11197 op != input_objects->relobj_end();
11200 Arm_relobj<big_endian>* arm_relobj =
11201 Arm_relobj<big_endian>::as_arm_relobj(*op);
11203 // Update output local symbol counts. We need to discard local
11204 // symbols defined in parts of input sections that are discarded by
11206 if (arm_relobj->output_local_symbol_count_needs_update())
11207 arm_relobj->update_output_local_symbol_count();
11211 return continue_relaxation;
11214 // Relocate a stub.
11216 template<bool big_endian>
11218 Target_arm<big_endian>::relocate_stub(
11220 const Relocate_info<32, big_endian>* relinfo,
11221 Output_section* output_section,
11222 unsigned char* view,
11223 Arm_address address,
11224 section_size_type view_size)
11227 const Stub_template* stub_template = stub->stub_template();
11228 for (size_t i = 0; i < stub_template->reloc_count(); i++)
11230 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
11231 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
11233 unsigned int r_type = insn->r_type();
11234 section_size_type reloc_offset = stub_template->reloc_offset(i);
11235 section_size_type reloc_size = insn->size();
11236 gold_assert(reloc_offset + reloc_size <= view_size);
11238 // This is the address of the stub destination.
11239 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
11240 Symbol_value<32> symval;
11241 symval.set_output_value(target);
11243 // Synthesize a fake reloc just in case. We don't have a symbol so
11245 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
11246 memset(reloc_buffer, 0, sizeof(reloc_buffer));
11247 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
11248 reloc_write.put_r_offset(reloc_offset);
11249 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
11250 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
11252 relocate.relocate(relinfo, this, output_section,
11253 this->fake_relnum_for_stubs, rel, r_type,
11254 NULL, &symval, view + reloc_offset,
11255 address + reloc_offset, reloc_size);
11259 // Determine whether an object attribute tag takes an integer, a
11262 template<bool big_endian>
11264 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
11266 if (tag == Object_attribute::Tag_compatibility)
11267 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11268 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
11269 else if (tag == elfcpp::Tag_nodefaults)
11270 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11271 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
11272 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
11273 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
11275 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
11277 return ((tag & 1) != 0
11278 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
11279 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
11282 // Reorder attributes.
11284 // The ABI defines that Tag_conformance should be emitted first, and that
11285 // Tag_nodefaults should be second (if either is defined). This sets those
11286 // two positions, and bumps up the position of all the remaining tags to
11289 template<bool big_endian>
11291 Target_arm<big_endian>::do_attributes_order(int num) const
11293 // Reorder the known object attributes in output. We want to move
11294 // Tag_conformance to position 4 and Tag_conformance to position 5
11295 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
11297 return elfcpp::Tag_conformance;
11299 return elfcpp::Tag_nodefaults;
11300 if ((num - 2) < elfcpp::Tag_nodefaults)
11302 if ((num - 1) < elfcpp::Tag_conformance)
11307 // Scan a span of THUMB code for Cortex-A8 erratum.
11309 template<bool big_endian>
11311 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
11312 Arm_relobj<big_endian>* arm_relobj,
11313 unsigned int shndx,
11314 section_size_type span_start,
11315 section_size_type span_end,
11316 const unsigned char* view,
11317 Arm_address address)
11319 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
11321 // The opcode is BLX.W, BL.W, B.W, Bcc.W
11322 // The branch target is in the same 4KB region as the
11323 // first half of the branch.
11324 // The instruction before the branch is a 32-bit
11325 // length non-branch instruction.
11326 section_size_type i = span_start;
11327 bool last_was_32bit = false;
11328 bool last_was_branch = false;
11329 while (i < span_end)
11331 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11332 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
11333 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
11334 bool is_blx = false, is_b = false;
11335 bool is_bl = false, is_bcc = false;
11337 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
11340 // Load the rest of the insn (in manual-friendly order).
11341 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
11343 // Encoding T4: B<c>.W.
11344 is_b = (insn & 0xf800d000U) == 0xf0009000U;
11345 // Encoding T1: BL<c>.W.
11346 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
11347 // Encoding T2: BLX<c>.W.
11348 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
11349 // Encoding T3: B<c>.W (not permitted in IT block).
11350 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
11351 && (insn & 0x07f00000U) != 0x03800000U);
11354 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
11356 // If this instruction is a 32-bit THUMB branch that crosses a 4K
11357 // page boundary and it follows 32-bit non-branch instruction,
11358 // we need to work around.
11359 if (is_32bit_branch
11360 && ((address + i) & 0xfffU) == 0xffeU
11362 && !last_was_branch)
11364 // Check to see if there is a relocation stub for this branch.
11365 bool force_target_arm = false;
11366 bool force_target_thumb = false;
11367 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
11368 Cortex_a8_relocs_info::const_iterator p =
11369 this->cortex_a8_relocs_info_.find(address + i);
11371 if (p != this->cortex_a8_relocs_info_.end())
11373 cortex_a8_reloc = p->second;
11374 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
11376 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11377 && !target_is_thumb)
11378 force_target_arm = true;
11379 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11380 && target_is_thumb)
11381 force_target_thumb = true;
11385 Stub_type stub_type = arm_stub_none;
11387 // Check if we have an offending branch instruction.
11388 uint16_t upper_insn = (insn >> 16) & 0xffffU;
11389 uint16_t lower_insn = insn & 0xffffU;
11390 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
11392 if (cortex_a8_reloc != NULL
11393 && cortex_a8_reloc->reloc_stub() != NULL)
11394 // We've already made a stub for this instruction, e.g.
11395 // it's a long branch or a Thumb->ARM stub. Assume that
11396 // stub will suffice to work around the A8 erratum (see
11397 // setting of always_after_branch above).
11401 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
11403 stub_type = arm_stub_a8_veneer_b_cond;
11405 else if (is_b || is_bl || is_blx)
11407 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
11412 stub_type = (is_blx
11413 ? arm_stub_a8_veneer_blx
11415 ? arm_stub_a8_veneer_bl
11416 : arm_stub_a8_veneer_b));
11419 if (stub_type != arm_stub_none)
11421 Arm_address pc_for_insn = address + i + 4;
11423 // The original instruction is a BL, but the target is
11424 // an ARM instruction. If we were not making a stub,
11425 // the BL would have been converted to a BLX. Use the
11426 // BLX stub instead in that case.
11427 if (this->may_use_blx() && force_target_arm
11428 && stub_type == arm_stub_a8_veneer_bl)
11430 stub_type = arm_stub_a8_veneer_blx;
11434 // Conversely, if the original instruction was
11435 // BLX but the target is Thumb mode, use the BL stub.
11436 else if (force_target_thumb
11437 && stub_type == arm_stub_a8_veneer_blx)
11439 stub_type = arm_stub_a8_veneer_bl;
11447 // If we found a relocation, use the proper destination,
11448 // not the offset in the (unrelocated) instruction.
11449 // Note this is always done if we switched the stub type above.
11450 if (cortex_a8_reloc != NULL)
11451 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
11453 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
11455 // Add a new stub if destination address in in the same page.
11456 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
11458 Cortex_a8_stub* stub =
11459 this->stub_factory_.make_cortex_a8_stub(stub_type,
11463 Stub_table<big_endian>* stub_table =
11464 arm_relobj->stub_table(shndx);
11465 gold_assert(stub_table != NULL);
11466 stub_table->add_cortex_a8_stub(address + i, stub);
11471 i += insn_32bit ? 4 : 2;
11472 last_was_32bit = insn_32bit;
11473 last_was_branch = is_32bit_branch;
11477 // Apply the Cortex-A8 workaround.
11479 template<bool big_endian>
11481 Target_arm<big_endian>::apply_cortex_a8_workaround(
11482 const Cortex_a8_stub* stub,
11483 Arm_address stub_address,
11484 unsigned char* insn_view,
11485 Arm_address insn_address)
11487 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11488 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
11489 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
11490 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
11491 off_t branch_offset = stub_address - (insn_address + 4);
11493 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
11494 switch (stub->stub_template()->type())
11496 case arm_stub_a8_veneer_b_cond:
11497 // For a conditional branch, we re-write it to be a uncondition
11498 // branch to the stub. We use the THUMB-2 encoding here.
11499 upper_insn = 0xf000U;
11500 lower_insn = 0xb800U;
11502 case arm_stub_a8_veneer_b:
11503 case arm_stub_a8_veneer_bl:
11504 case arm_stub_a8_veneer_blx:
11505 if ((lower_insn & 0x5000U) == 0x4000U)
11506 // For a BLX instruction, make sure that the relocation is
11507 // rounded up to a word boundary. This follows the semantics of
11508 // the instruction which specifies that bit 1 of the target
11509 // address will come from bit 1 of the base address.
11510 branch_offset = (branch_offset + 2) & ~3;
11512 // Put BRANCH_OFFSET back into the insn.
11513 gold_assert(!utils::has_overflow<25>(branch_offset));
11514 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
11515 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
11519 gold_unreachable();
11522 // Put the relocated value back in the object file:
11523 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
11524 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
11527 template<bool big_endian>
11528 class Target_selector_arm : public Target_selector
11531 Target_selector_arm()
11532 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
11533 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
11537 do_instantiate_target()
11538 { return new Target_arm<big_endian>(); }
11541 // Fix .ARM.exidx section coverage.
11543 template<bool big_endian>
11545 Target_arm<big_endian>::fix_exidx_coverage(
11547 const Input_objects* input_objects,
11548 Arm_output_section<big_endian>* exidx_section,
11549 Symbol_table* symtab)
11551 // We need to look at all the input sections in output in ascending
11552 // order of of output address. We do that by building a sorted list
11553 // of output sections by addresses. Then we looks at the output sections
11554 // in order. The input sections in an output section are already sorted
11555 // by addresses within the output section.
11557 typedef std::set<Output_section*, output_section_address_less_than>
11558 Sorted_output_section_list;
11559 Sorted_output_section_list sorted_output_sections;
11561 // Find out all the output sections of input sections pointed by
11562 // EXIDX input sections.
11563 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
11564 p != input_objects->relobj_end();
11567 Arm_relobj<big_endian>* arm_relobj =
11568 Arm_relobj<big_endian>::as_arm_relobj(*p);
11569 std::vector<unsigned int> shndx_list;
11570 arm_relobj->get_exidx_shndx_list(&shndx_list);
11571 for (size_t i = 0; i < shndx_list.size(); ++i)
11573 const Arm_exidx_input_section* exidx_input_section =
11574 arm_relobj->exidx_input_section_by_shndx(shndx_list[i]);
11575 gold_assert(exidx_input_section != NULL);
11576 if (!exidx_input_section->has_errors())
11578 unsigned int text_shndx = exidx_input_section->link();
11579 Output_section *os = arm_relobj->output_section(text_shndx);
11580 if (os != NULL && (os->flags() & elfcpp::SHF_ALLOC) != 0)
11581 sorted_output_sections.insert(os);
11586 // Go over the output sections in ascending order of output addresses.
11587 typedef typename Arm_output_section<big_endian>::Text_section_list
11589 Text_section_list sorted_text_sections;
11590 for(typename Sorted_output_section_list::iterator p =
11591 sorted_output_sections.begin();
11592 p != sorted_output_sections.end();
11595 Arm_output_section<big_endian>* arm_output_section =
11596 Arm_output_section<big_endian>::as_arm_output_section(*p);
11597 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
11600 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab,
11601 merge_exidx_entries());
11604 Target_selector_arm<false> target_selector_arm;
11605 Target_selector_arm<true> target_selector_armbe;
11607 } // End anonymous namespace.