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);
1067 // Write to a map file.
1069 do_print_to_mapfile(Mapfile* mapfile) const
1070 { mapfile->print_output_data(this, _("** ARM cantunwind")); }
1073 // Implement do_write for a given endianness.
1074 template<bool big_endian>
1076 do_fixed_endian_write(Output_file*);
1078 // The object containing the section pointed by this.
1080 // The section index of the section pointed by this.
1081 unsigned int shndx_;
1084 // During EXIDX coverage fix-up, we compact an EXIDX section. The
1085 // Offset map is used to map input section offset within the EXIDX section
1086 // to the output offset from the start of this EXIDX section.
1088 typedef std::map<section_offset_type, section_offset_type>
1089 Arm_exidx_section_offset_map;
1091 // Arm_exidx_merged_section class. This represents an EXIDX input section
1092 // with some of its entries merged.
1094 class Arm_exidx_merged_section : public Output_relaxed_input_section
1097 // Constructor for Arm_exidx_merged_section.
1098 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
1099 // SECTION_OFFSET_MAP points to a section offset map describing how
1100 // parts of the input section are mapped to output. DELETED_BYTES is
1101 // the number of bytes deleted from the EXIDX input section.
1102 Arm_exidx_merged_section(
1103 const Arm_exidx_input_section& exidx_input_section,
1104 const Arm_exidx_section_offset_map& section_offset_map,
1105 uint32_t deleted_bytes);
1107 // Return the original EXIDX input section.
1108 const Arm_exidx_input_section&
1109 exidx_input_section() const
1110 { return this->exidx_input_section_; }
1112 // Return the section offset map.
1113 const Arm_exidx_section_offset_map&
1114 section_offset_map() const
1115 { return this->section_offset_map_; }
1118 // Write merged section into file OF.
1120 do_write(Output_file* of);
1123 do_output_offset(const Relobj*, unsigned int, section_offset_type,
1124 section_offset_type*) const;
1127 // Original EXIDX input section.
1128 const Arm_exidx_input_section& exidx_input_section_;
1129 // Section offset map.
1130 const Arm_exidx_section_offset_map& section_offset_map_;
1133 // A class to wrap an ordinary input section containing executable code.
1135 template<bool big_endian>
1136 class Arm_input_section : public Output_relaxed_input_section
1139 Arm_input_section(Relobj* relobj, unsigned int shndx)
1140 : Output_relaxed_input_section(relobj, shndx, 1),
1141 original_addralign_(1), original_size_(0), stub_table_(NULL)
1144 ~Arm_input_section()
1151 // Whether this is a stub table owner.
1153 is_stub_table_owner() const
1154 { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
1156 // Return the stub table.
1157 Stub_table<big_endian>*
1159 { return this->stub_table_; }
1161 // Set the stub_table.
1163 set_stub_table(Stub_table<big_endian>* stub_table)
1164 { this->stub_table_ = stub_table; }
1166 // Downcast a base pointer to an Arm_input_section pointer. This is
1167 // not type-safe but we only use Arm_input_section not the base class.
1168 static Arm_input_section<big_endian>*
1169 as_arm_input_section(Output_relaxed_input_section* poris)
1170 { return static_cast<Arm_input_section<big_endian>*>(poris); }
1172 // Return the original size of the section.
1174 original_size() const
1175 { return this->original_size_; }
1178 // Write data to output file.
1180 do_write(Output_file*);
1182 // Return required alignment of this.
1184 do_addralign() const
1186 if (this->is_stub_table_owner())
1187 return std::max(this->stub_table_->addralign(),
1188 static_cast<uint64_t>(this->original_addralign_));
1190 return this->original_addralign_;
1193 // Finalize data size.
1195 set_final_data_size();
1197 // Reset address and file offset.
1199 do_reset_address_and_file_offset();
1203 do_output_offset(const Relobj* object, unsigned int shndx,
1204 section_offset_type offset,
1205 section_offset_type* poutput) const
1207 if ((object == this->relobj())
1208 && (shndx == this->shndx())
1211 convert_types<section_offset_type, uint32_t>(this->original_size_)))
1221 // Copying is not allowed.
1222 Arm_input_section(const Arm_input_section&);
1223 Arm_input_section& operator=(const Arm_input_section&);
1225 // Address alignment of the original input section.
1226 uint32_t original_addralign_;
1227 // Section size of the original input section.
1228 uint32_t original_size_;
1230 Stub_table<big_endian>* stub_table_;
1233 // Arm_exidx_fixup class. This is used to define a number of methods
1234 // and keep states for fixing up EXIDX coverage.
1236 class Arm_exidx_fixup
1239 Arm_exidx_fixup(Output_section* exidx_output_section,
1240 bool merge_exidx_entries = true)
1241 : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
1242 last_inlined_entry_(0), last_input_section_(NULL),
1243 section_offset_map_(NULL), first_output_text_section_(NULL),
1244 merge_exidx_entries_(merge_exidx_entries)
1248 { delete this->section_offset_map_; }
1250 // Process an EXIDX section for entry merging. Return number of bytes to
1251 // be deleted in output. If parts of the input EXIDX section are merged
1252 // a heap allocated Arm_exidx_section_offset_map is store in the located
1253 // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
1255 template<bool big_endian>
1257 process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
1258 Arm_exidx_section_offset_map** psection_offset_map);
1260 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1261 // input section, if there is not one already.
1263 add_exidx_cantunwind_as_needed();
1265 // Return the output section for the text section which is linked to the
1266 // first exidx input in output.
1268 first_output_text_section() const
1269 { return this->first_output_text_section_; }
1272 // Copying is not allowed.
1273 Arm_exidx_fixup(const Arm_exidx_fixup&);
1274 Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
1276 // Type of EXIDX unwind entry.
1281 // EXIDX_CANTUNWIND.
1282 UT_EXIDX_CANTUNWIND,
1289 // Process an EXIDX entry. We only care about the second word of the
1290 // entry. Return true if the entry can be deleted.
1292 process_exidx_entry(uint32_t second_word);
1294 // Update the current section offset map during EXIDX section fix-up.
1295 // If there is no map, create one. INPUT_OFFSET is the offset of a
1296 // reference point, DELETED_BYTES is the number of deleted by in the
1297 // section so far. If DELETE_ENTRY is true, the reference point and
1298 // all offsets after the previous reference point are discarded.
1300 update_offset_map(section_offset_type input_offset,
1301 section_size_type deleted_bytes, bool delete_entry);
1303 // EXIDX output section.
1304 Output_section* exidx_output_section_;
1305 // Unwind type of the last EXIDX entry processed.
1306 Unwind_type last_unwind_type_;
1307 // Last seen inlined EXIDX entry.
1308 uint32_t last_inlined_entry_;
1309 // Last processed EXIDX input section.
1310 const Arm_exidx_input_section* last_input_section_;
1311 // Section offset map created in process_exidx_section.
1312 Arm_exidx_section_offset_map* section_offset_map_;
1313 // Output section for the text section which is linked to the first exidx
1315 Output_section* first_output_text_section_;
1317 bool merge_exidx_entries_;
1320 // Arm output section class. This is defined mainly to add a number of
1321 // stub generation methods.
1323 template<bool big_endian>
1324 class Arm_output_section : public Output_section
1327 typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
1329 Arm_output_section(const char* name, elfcpp::Elf_Word type,
1330 elfcpp::Elf_Xword flags)
1331 : Output_section(name, type, flags)
1333 if (type == elfcpp::SHT_ARM_EXIDX)
1334 this->set_always_keeps_input_sections();
1337 ~Arm_output_section()
1340 // Group input sections for stub generation.
1342 group_sections(section_size_type, bool, Target_arm<big_endian>*);
1344 // Downcast a base pointer to an Arm_output_section pointer. This is
1345 // not type-safe but we only use Arm_output_section not the base class.
1346 static Arm_output_section<big_endian>*
1347 as_arm_output_section(Output_section* os)
1348 { return static_cast<Arm_output_section<big_endian>*>(os); }
1350 // Append all input text sections in this into LIST.
1352 append_text_sections_to_list(Text_section_list* list);
1354 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1355 // is a list of text input sections sorted in ascending order of their
1356 // output addresses.
1358 fix_exidx_coverage(Layout* layout,
1359 const Text_section_list& sorted_text_section,
1360 Symbol_table* symtab,
1361 bool merge_exidx_entries);
1363 // Link an EXIDX section into its corresponding text section.
1365 set_exidx_section_link();
1369 typedef Output_section::Input_section Input_section;
1370 typedef Output_section::Input_section_list Input_section_list;
1372 // Create a stub group.
1373 void create_stub_group(Input_section_list::const_iterator,
1374 Input_section_list::const_iterator,
1375 Input_section_list::const_iterator,
1376 Target_arm<big_endian>*,
1377 std::vector<Output_relaxed_input_section*>*);
1380 // Arm_exidx_input_section class. This represents an EXIDX input section.
1382 class Arm_exidx_input_section
1385 static const section_offset_type invalid_offset =
1386 static_cast<section_offset_type>(-1);
1388 Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
1389 unsigned int link, uint32_t size, uint32_t addralign)
1390 : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
1391 addralign_(addralign), has_errors_(false)
1394 ~Arm_exidx_input_section()
1397 // Accessors: This is a read-only class.
1399 // Return the object containing this EXIDX input section.
1402 { return this->relobj_; }
1404 // Return the section index of this EXIDX input section.
1407 { return this->shndx_; }
1409 // Return the section index of linked text section in the same object.
1412 { return this->link_; }
1414 // Return size of the EXIDX input section.
1417 { return this->size_; }
1419 // Reutnr address alignment of EXIDX input section.
1422 { return this->addralign_; }
1424 // Whether there are any errors in the EXIDX input section.
1427 { return this->has_errors_; }
1429 // Set has-errors flag.
1432 { this->has_errors_ = true; }
1435 // Object containing this.
1437 // Section index of this.
1438 unsigned int shndx_;
1439 // text section linked to this in the same object.
1441 // Size of this. For ARM 32-bit is sufficient.
1443 // Address alignment of this. For ARM 32-bit is sufficient.
1444 uint32_t addralign_;
1445 // Whether this has any errors.
1449 // Arm_relobj class.
1451 template<bool big_endian>
1452 class Arm_relobj : public Sized_relobj<32, big_endian>
1455 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
1457 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
1458 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
1459 : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
1460 stub_tables_(), local_symbol_is_thumb_function_(),
1461 attributes_section_data_(NULL), mapping_symbols_info_(),
1462 section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
1463 output_local_symbol_count_needs_update_(false),
1464 merge_flags_and_attributes_(true)
1468 { delete this->attributes_section_data_; }
1470 // Return the stub table of the SHNDX-th section if there is one.
1471 Stub_table<big_endian>*
1472 stub_table(unsigned int shndx) const
1474 gold_assert(shndx < this->stub_tables_.size());
1475 return this->stub_tables_[shndx];
1478 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1480 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
1482 gold_assert(shndx < this->stub_tables_.size());
1483 this->stub_tables_[shndx] = stub_table;
1486 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1487 // index. This is only valid after do_count_local_symbol is called.
1489 local_symbol_is_thumb_function(unsigned int r_sym) const
1491 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
1492 return this->local_symbol_is_thumb_function_[r_sym];
1495 // Scan all relocation sections for stub generation.
1497 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
1500 // Convert regular input section with index SHNDX to a relaxed section.
1502 convert_input_section_to_relaxed_section(unsigned shndx)
1504 // The stubs have relocations and we need to process them after writing
1505 // out the stubs. So relocation now must follow section write.
1506 this->set_section_offset(shndx, -1ULL);
1507 this->set_relocs_must_follow_section_writes();
1510 // Downcast a base pointer to an Arm_relobj pointer. This is
1511 // not type-safe but we only use Arm_relobj not the base class.
1512 static Arm_relobj<big_endian>*
1513 as_arm_relobj(Relobj* relobj)
1514 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
1516 // Processor-specific flags in ELF file header. This is valid only after
1519 processor_specific_flags() const
1520 { return this->processor_specific_flags_; }
1522 // Attribute section data This is the contents of the .ARM.attribute section
1524 const Attributes_section_data*
1525 attributes_section_data() const
1526 { return this->attributes_section_data_; }
1528 // Mapping symbol location.
1529 typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
1531 // Functor for STL container.
1532 struct Mapping_symbol_position_less
1535 operator()(const Mapping_symbol_position& p1,
1536 const Mapping_symbol_position& p2) const
1538 return (p1.first < p2.first
1539 || (p1.first == p2.first && p1.second < p2.second));
1543 // We only care about the first character of a mapping symbol, so
1544 // we only store that instead of the whole symbol name.
1545 typedef std::map<Mapping_symbol_position, char,
1546 Mapping_symbol_position_less> Mapping_symbols_info;
1548 // Whether a section contains any Cortex-A8 workaround.
1550 section_has_cortex_a8_workaround(unsigned int shndx) const
1552 return (this->section_has_cortex_a8_workaround_ != NULL
1553 && (*this->section_has_cortex_a8_workaround_)[shndx]);
1556 // Mark a section that has Cortex-A8 workaround.
1558 mark_section_for_cortex_a8_workaround(unsigned int shndx)
1560 if (this->section_has_cortex_a8_workaround_ == NULL)
1561 this->section_has_cortex_a8_workaround_ =
1562 new std::vector<bool>(this->shnum(), false);
1563 (*this->section_has_cortex_a8_workaround_)[shndx] = true;
1566 // Return the EXIDX section of an text section with index SHNDX or NULL
1567 // if the text section has no associated EXIDX section.
1568 const Arm_exidx_input_section*
1569 exidx_input_section_by_link(unsigned int shndx) const
1571 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1572 return ((p != this->exidx_section_map_.end()
1573 && p->second->link() == shndx)
1578 // Return the EXIDX section with index SHNDX or NULL if there is none.
1579 const Arm_exidx_input_section*
1580 exidx_input_section_by_shndx(unsigned shndx) const
1582 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1583 return ((p != this->exidx_section_map_.end()
1584 && p->second->shndx() == shndx)
1589 // Whether output local symbol count needs updating.
1591 output_local_symbol_count_needs_update() const
1592 { return this->output_local_symbol_count_needs_update_; }
1594 // Set output_local_symbol_count_needs_update flag to be true.
1596 set_output_local_symbol_count_needs_update()
1597 { this->output_local_symbol_count_needs_update_ = true; }
1599 // Update output local symbol count at the end of relaxation.
1601 update_output_local_symbol_count();
1603 // Whether we want to merge processor-specific flags and attributes.
1605 merge_flags_and_attributes() const
1606 { return this->merge_flags_and_attributes_; }
1608 // Export list of EXIDX section indices.
1610 get_exidx_shndx_list(std::vector<unsigned int>* list) const
1613 for (Exidx_section_map::const_iterator p = this->exidx_section_map_.begin();
1614 p != this->exidx_section_map_.end();
1617 if (p->second->shndx() == p->first)
1618 list->push_back(p->first);
1620 // Sort list to make result independent of implementation of map.
1621 std::sort(list->begin(), list->end());
1625 // Post constructor setup.
1629 // Call parent's setup method.
1630 Sized_relobj<32, big_endian>::do_setup();
1632 // Initialize look-up tables.
1633 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
1634 this->stub_tables_.swap(empty_stub_table_list);
1637 // Count the local symbols.
1639 do_count_local_symbols(Stringpool_template<char>*,
1640 Stringpool_template<char>*);
1643 do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
1644 const unsigned char* pshdrs, Output_file* of,
1645 typename Sized_relobj<32, big_endian>::Views* pivews);
1647 // Read the symbol information.
1649 do_read_symbols(Read_symbols_data* sd);
1651 // Process relocs for garbage collection.
1653 do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
1657 // Whether a section needs to be scanned for relocation stubs.
1659 section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1660 const Relobj::Output_sections&,
1661 const Symbol_table*, const unsigned char*);
1663 // Whether a section is a scannable text section.
1665 section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
1666 const Output_section*, const Symbol_table*);
1668 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1670 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1671 unsigned int, Output_section*,
1672 const Symbol_table*);
1674 // Scan a section for the Cortex-A8 erratum.
1676 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
1677 unsigned int, Output_section*,
1678 Target_arm<big_endian>*);
1680 // Find the linked text section of an EXIDX section by looking at the
1681 // first reloction of the EXIDX section. PSHDR points to the section
1682 // headers of a relocation section and PSYMS points to the local symbols.
1683 // PSHNDX points to a location storing the text section index if found.
1684 // Return whether we can find the linked section.
1686 find_linked_text_section(const unsigned char* pshdr,
1687 const unsigned char* psyms, unsigned int* pshndx);
1690 // Make a new Arm_exidx_input_section object for EXIDX section with
1691 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1692 // index of the linked text section.
1694 make_exidx_input_section(unsigned int shndx,
1695 const elfcpp::Shdr<32, big_endian>& shdr,
1696 unsigned int text_shndx,
1697 const elfcpp::Shdr<32, big_endian>& text_shdr);
1699 // Return the output address of either a plain input section or a
1700 // relaxed input section. SHNDX is the section index.
1702 simple_input_section_output_address(unsigned int, Output_section*);
1704 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
1705 typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
1708 // List of stub tables.
1709 Stub_table_list stub_tables_;
1710 // Bit vector to tell if a local symbol is a thumb function or not.
1711 // This is only valid after do_count_local_symbol is called.
1712 std::vector<bool> local_symbol_is_thumb_function_;
1713 // processor-specific flags in ELF file header.
1714 elfcpp::Elf_Word processor_specific_flags_;
1715 // Object attributes if there is an .ARM.attributes section or NULL.
1716 Attributes_section_data* attributes_section_data_;
1717 // Mapping symbols information.
1718 Mapping_symbols_info mapping_symbols_info_;
1719 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1720 std::vector<bool>* section_has_cortex_a8_workaround_;
1721 // Map a text section to its associated .ARM.exidx section, if there is one.
1722 Exidx_section_map exidx_section_map_;
1723 // Whether output local symbol count needs updating.
1724 bool output_local_symbol_count_needs_update_;
1725 // Whether we merge processor flags and attributes of this object to
1727 bool merge_flags_and_attributes_;
1730 // Arm_dynobj class.
1732 template<bool big_endian>
1733 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1736 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1737 const elfcpp::Ehdr<32, big_endian>& ehdr)
1738 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1739 processor_specific_flags_(0), attributes_section_data_(NULL)
1743 { delete this->attributes_section_data_; }
1745 // Downcast a base pointer to an Arm_relobj pointer. This is
1746 // not type-safe but we only use Arm_relobj not the base class.
1747 static Arm_dynobj<big_endian>*
1748 as_arm_dynobj(Dynobj* dynobj)
1749 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1751 // Processor-specific flags in ELF file header. This is valid only after
1754 processor_specific_flags() const
1755 { return this->processor_specific_flags_; }
1757 // Attributes section data.
1758 const Attributes_section_data*
1759 attributes_section_data() const
1760 { return this->attributes_section_data_; }
1763 // Read the symbol information.
1765 do_read_symbols(Read_symbols_data* sd);
1768 // processor-specific flags in ELF file header.
1769 elfcpp::Elf_Word processor_specific_flags_;
1770 // Object attributes if there is an .ARM.attributes section or NULL.
1771 Attributes_section_data* attributes_section_data_;
1774 // Functor to read reloc addends during stub generation.
1776 template<int sh_type, bool big_endian>
1777 struct Stub_addend_reader
1779 // Return the addend for a relocation of a particular type. Depending
1780 // on whether this is a REL or RELA relocation, read the addend from a
1781 // view or from a Reloc object.
1782 elfcpp::Elf_types<32>::Elf_Swxword
1784 unsigned int /* r_type */,
1785 const unsigned char* /* view */,
1786 const typename Reloc_types<sh_type,
1787 32, big_endian>::Reloc& /* reloc */) const;
1790 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1792 template<bool big_endian>
1793 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1795 elfcpp::Elf_types<32>::Elf_Swxword
1798 const unsigned char*,
1799 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1802 // Specialized Stub_addend_reader for RELA type relocation sections.
1803 // We currently do not handle RELA type relocation sections but it is trivial
1804 // to implement the addend reader. This is provided for completeness and to
1805 // make it easier to add support for RELA relocation sections in the future.
1807 template<bool big_endian>
1808 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1810 elfcpp::Elf_types<32>::Elf_Swxword
1813 const unsigned char*,
1814 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1815 big_endian>::Reloc& reloc) const
1816 { return reloc.get_r_addend(); }
1819 // Cortex_a8_reloc class. We keep record of relocation that may need
1820 // the Cortex-A8 erratum workaround.
1822 class Cortex_a8_reloc
1825 Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
1826 Arm_address destination)
1827 : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
1833 // Accessors: This is a read-only class.
1835 // Return the relocation stub associated with this relocation if there is
1839 { return this->reloc_stub_; }
1841 // Return the relocation type.
1844 { return this->r_type_; }
1846 // Return the destination address of the relocation. LSB stores the THUMB
1850 { return this->destination_; }
1853 // Associated relocation stub if there is one, or NULL.
1854 const Reloc_stub* reloc_stub_;
1856 unsigned int r_type_;
1857 // Destination address of this relocation. LSB is used to distinguish
1859 Arm_address destination_;
1862 // Arm_output_data_got class. We derive this from Output_data_got to add
1863 // extra methods to handle TLS relocations in a static link.
1865 template<bool big_endian>
1866 class Arm_output_data_got : public Output_data_got<32, big_endian>
1869 Arm_output_data_got(Symbol_table* symtab, Layout* layout)
1870 : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
1873 // Add a static entry for the GOT entry at OFFSET. GSYM is a global
1874 // symbol and R_TYPE is the code of a dynamic relocation that needs to be
1875 // applied in a static link.
1877 add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1878 { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
1880 // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
1881 // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
1882 // relocation that needs to be applied in a static link.
1884 add_static_reloc(unsigned int got_offset, unsigned int r_type,
1885 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1887 this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
1891 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
1892 // The first one is initialized to be 1, which is the module index for
1893 // the main executable and the second one 0. A reloc of the type
1894 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
1895 // be applied by gold. GSYM is a global symbol.
1897 add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
1899 // Same as the above but for a local symbol in OBJECT with INDEX.
1901 add_tls_gd32_with_static_reloc(unsigned int got_type,
1902 Sized_relobj<32, big_endian>* object,
1903 unsigned int index);
1906 // Write out the GOT table.
1908 do_write(Output_file*);
1911 // This class represent dynamic relocations that need to be applied by
1912 // gold because we are using TLS relocations in a static link.
1916 Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1917 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
1918 { this->u_.global.symbol = gsym; }
1920 Static_reloc(unsigned int got_offset, unsigned int r_type,
1921 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1922 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
1924 this->u_.local.relobj = relobj;
1925 this->u_.local.index = index;
1928 // Return the GOT offset.
1931 { return this->got_offset_; }
1936 { return this->r_type_; }
1938 // Whether the symbol is global or not.
1940 symbol_is_global() const
1941 { return this->symbol_is_global_; }
1943 // For a relocation against a global symbol, the global symbol.
1947 gold_assert(this->symbol_is_global_);
1948 return this->u_.global.symbol;
1951 // For a relocation against a local symbol, the defining object.
1952 Sized_relobj<32, big_endian>*
1955 gold_assert(!this->symbol_is_global_);
1956 return this->u_.local.relobj;
1959 // For a relocation against a local symbol, the local symbol index.
1963 gold_assert(!this->symbol_is_global_);
1964 return this->u_.local.index;
1968 // GOT offset of the entry to which this relocation is applied.
1969 unsigned int got_offset_;
1970 // Type of relocation.
1971 unsigned int r_type_;
1972 // Whether this relocation is against a global symbol.
1973 bool symbol_is_global_;
1974 // A global or local symbol.
1979 // For a global symbol, the symbol itself.
1984 // For a local symbol, the object defining object.
1985 Sized_relobj<32, big_endian>* relobj;
1986 // For a local symbol, the symbol index.
1992 // Symbol table of the output object.
1993 Symbol_table* symbol_table_;
1994 // Layout of the output object.
1996 // Static relocs to be applied to the GOT.
1997 std::vector<Static_reloc> static_relocs_;
2000 // The ARM target has many relocation types with odd-sizes or incontigious
2001 // bits. The default handling of relocatable relocation cannot process these
2002 // relocations. So we have to extend the default code.
2004 template<bool big_endian, int sh_type, typename Classify_reloc>
2005 class Arm_scan_relocatable_relocs :
2006 public Default_scan_relocatable_relocs<sh_type, Classify_reloc>
2009 // Return the strategy to use for a local symbol which is a section
2010 // symbol, given the relocation type.
2011 inline Relocatable_relocs::Reloc_strategy
2012 local_section_strategy(unsigned int r_type, Relobj*)
2014 if (sh_type == elfcpp::SHT_RELA)
2015 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
2018 if (r_type == elfcpp::R_ARM_TARGET1
2019 || r_type == elfcpp::R_ARM_TARGET2)
2021 const Target_arm<big_endian>* arm_target =
2022 Target_arm<big_endian>::default_target();
2023 r_type = arm_target->get_real_reloc_type(r_type);
2028 // Relocations that write nothing. These exclude R_ARM_TARGET1
2029 // and R_ARM_TARGET2.
2030 case elfcpp::R_ARM_NONE:
2031 case elfcpp::R_ARM_V4BX:
2032 case elfcpp::R_ARM_TLS_GOTDESC:
2033 case elfcpp::R_ARM_TLS_CALL:
2034 case elfcpp::R_ARM_TLS_DESCSEQ:
2035 case elfcpp::R_ARM_THM_TLS_CALL:
2036 case elfcpp::R_ARM_GOTRELAX:
2037 case elfcpp::R_ARM_GNU_VTENTRY:
2038 case elfcpp::R_ARM_GNU_VTINHERIT:
2039 case elfcpp::R_ARM_THM_TLS_DESCSEQ16:
2040 case elfcpp::R_ARM_THM_TLS_DESCSEQ32:
2041 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
2042 // These should have been converted to something else above.
2043 case elfcpp::R_ARM_TARGET1:
2044 case elfcpp::R_ARM_TARGET2:
2046 // Relocations that write full 32 bits.
2047 case elfcpp::R_ARM_ABS32:
2048 case elfcpp::R_ARM_REL32:
2049 case elfcpp::R_ARM_SBREL32:
2050 case elfcpp::R_ARM_GOTOFF32:
2051 case elfcpp::R_ARM_BASE_PREL:
2052 case elfcpp::R_ARM_GOT_BREL:
2053 case elfcpp::R_ARM_BASE_ABS:
2054 case elfcpp::R_ARM_ABS32_NOI:
2055 case elfcpp::R_ARM_REL32_NOI:
2056 case elfcpp::R_ARM_PLT32_ABS:
2057 case elfcpp::R_ARM_GOT_ABS:
2058 case elfcpp::R_ARM_GOT_PREL:
2059 case elfcpp::R_ARM_TLS_GD32:
2060 case elfcpp::R_ARM_TLS_LDM32:
2061 case elfcpp::R_ARM_TLS_LDO32:
2062 case elfcpp::R_ARM_TLS_IE32:
2063 case elfcpp::R_ARM_TLS_LE32:
2064 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
2066 // For all other static relocations, return RELOC_SPECIAL.
2067 return Relocatable_relocs::RELOC_SPECIAL;
2073 // Utilities for manipulating integers of up to 32-bits
2077 // Sign extend an n-bit unsigned integer stored in an uint32_t into
2078 // an int32_t. NO_BITS must be between 1 to 32.
2079 template<int no_bits>
2080 static inline int32_t
2081 sign_extend(uint32_t bits)
2083 gold_assert(no_bits >= 0 && no_bits <= 32);
2085 return static_cast<int32_t>(bits);
2086 uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
2088 uint32_t top_bit = 1U << (no_bits - 1);
2089 int32_t as_signed = static_cast<int32_t>(bits);
2090 return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
2093 // Detects overflow of an NO_BITS integer stored in a uint32_t.
2094 template<int no_bits>
2096 has_overflow(uint32_t bits)
2098 gold_assert(no_bits >= 0 && no_bits <= 32);
2101 int32_t max = (1 << (no_bits - 1)) - 1;
2102 int32_t min = -(1 << (no_bits - 1));
2103 int32_t as_signed = static_cast<int32_t>(bits);
2104 return as_signed > max || as_signed < min;
2107 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
2108 // fits in the given number of bits as either a signed or unsigned value.
2109 // For example, has_signed_unsigned_overflow<8> would check
2110 // -128 <= bits <= 255
2111 template<int no_bits>
2113 has_signed_unsigned_overflow(uint32_t bits)
2115 gold_assert(no_bits >= 2 && no_bits <= 32);
2118 int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
2119 int32_t min = -(1 << (no_bits - 1));
2120 int32_t as_signed = static_cast<int32_t>(bits);
2121 return as_signed > max || as_signed < min;
2124 // Select bits from A and B using bits in MASK. For each n in [0..31],
2125 // the n-th bit in the result is chosen from the n-th bits of A and B.
2126 // A zero selects A and a one selects B.
2127 static inline uint32_t
2128 bit_select(uint32_t a, uint32_t b, uint32_t mask)
2129 { return (a & ~mask) | (b & mask); }
2132 template<bool big_endian>
2133 class Target_arm : public Sized_target<32, big_endian>
2136 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
2139 // When were are relocating a stub, we pass this as the relocation number.
2140 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
2143 : Sized_target<32, big_endian>(&arm_info),
2144 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
2145 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
2146 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
2147 stub_tables_(), stub_factory_(Stub_factory::get_instance()),
2148 may_use_blx_(false), should_force_pic_veneer_(false),
2149 arm_input_section_map_(), attributes_section_data_(NULL),
2150 fix_cortex_a8_(false), cortex_a8_relocs_info_()
2153 // Virtual function which is set to return true by a target if
2154 // it can use relocation types to determine if a function's
2155 // pointer is taken.
2157 can_check_for_function_pointers() const
2160 // Whether a section called SECTION_NAME may have function pointers to
2161 // sections not eligible for safe ICF folding.
2163 section_may_have_icf_unsafe_pointers(const char* section_name) const
2165 return (!is_prefix_of(".ARM.exidx", section_name)
2166 && !is_prefix_of(".ARM.extab", section_name)
2167 && Target::section_may_have_icf_unsafe_pointers(section_name));
2170 // Whether we can use BLX.
2173 { return this->may_use_blx_; }
2175 // Set use-BLX flag.
2177 set_may_use_blx(bool value)
2178 { this->may_use_blx_ = value; }
2180 // Whether we force PCI branch veneers.
2182 should_force_pic_veneer() const
2183 { return this->should_force_pic_veneer_; }
2185 // Set PIC veneer flag.
2187 set_should_force_pic_veneer(bool value)
2188 { this->should_force_pic_veneer_ = value; }
2190 // Whether we use THUMB-2 instructions.
2192 using_thumb2() const
2194 Object_attribute* attr =
2195 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2196 int arch = attr->int_value();
2197 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
2200 // Whether we use THUMB/THUMB-2 instructions only.
2202 using_thumb_only() const
2204 Object_attribute* attr =
2205 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2207 if (attr->int_value() == elfcpp::TAG_CPU_ARCH_V6_M
2208 || attr->int_value() == elfcpp::TAG_CPU_ARCH_V6S_M)
2210 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2211 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2213 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2214 return attr->int_value() == 'M';
2217 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2219 may_use_arm_nop() const
2221 Object_attribute* attr =
2222 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2223 int arch = attr->int_value();
2224 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2225 || arch == elfcpp::TAG_CPU_ARCH_V6K
2226 || arch == elfcpp::TAG_CPU_ARCH_V7
2227 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2230 // Whether we have THUMB-2 NOP.W instruction.
2232 may_use_thumb2_nop() const
2234 Object_attribute* attr =
2235 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2236 int arch = attr->int_value();
2237 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2238 || arch == elfcpp::TAG_CPU_ARCH_V7
2239 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2242 // Process the relocations to determine unreferenced sections for
2243 // garbage collection.
2245 gc_process_relocs(Symbol_table* symtab,
2247 Sized_relobj<32, big_endian>* object,
2248 unsigned int data_shndx,
2249 unsigned int sh_type,
2250 const unsigned char* prelocs,
2252 Output_section* output_section,
2253 bool needs_special_offset_handling,
2254 size_t local_symbol_count,
2255 const unsigned char* plocal_symbols);
2257 // Scan the relocations to look for symbol adjustments.
2259 scan_relocs(Symbol_table* symtab,
2261 Sized_relobj<32, big_endian>* object,
2262 unsigned int data_shndx,
2263 unsigned int sh_type,
2264 const unsigned char* prelocs,
2266 Output_section* output_section,
2267 bool needs_special_offset_handling,
2268 size_t local_symbol_count,
2269 const unsigned char* plocal_symbols);
2271 // Finalize the sections.
2273 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2275 // Return the value to use for a dynamic symbol which requires special
2278 do_dynsym_value(const Symbol*) const;
2280 // Relocate a section.
2282 relocate_section(const Relocate_info<32, big_endian>*,
2283 unsigned int sh_type,
2284 const unsigned char* prelocs,
2286 Output_section* output_section,
2287 bool needs_special_offset_handling,
2288 unsigned char* view,
2289 Arm_address view_address,
2290 section_size_type view_size,
2291 const Reloc_symbol_changes*);
2293 // Scan the relocs during a relocatable link.
2295 scan_relocatable_relocs(Symbol_table* symtab,
2297 Sized_relobj<32, big_endian>* object,
2298 unsigned int data_shndx,
2299 unsigned int sh_type,
2300 const unsigned char* prelocs,
2302 Output_section* output_section,
2303 bool needs_special_offset_handling,
2304 size_t local_symbol_count,
2305 const unsigned char* plocal_symbols,
2306 Relocatable_relocs*);
2308 // Relocate a section during a relocatable link.
2310 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
2311 unsigned int sh_type,
2312 const unsigned char* prelocs,
2314 Output_section* output_section,
2315 off_t offset_in_output_section,
2316 const Relocatable_relocs*,
2317 unsigned char* view,
2318 Arm_address view_address,
2319 section_size_type view_size,
2320 unsigned char* reloc_view,
2321 section_size_type reloc_view_size);
2323 // Perform target-specific processing in a relocatable link. This is
2324 // only used if we use the relocation strategy RELOC_SPECIAL.
2326 relocate_special_relocatable(const Relocate_info<32, big_endian>* relinfo,
2327 unsigned int sh_type,
2328 const unsigned char* preloc_in,
2330 Output_section* output_section,
2331 off_t offset_in_output_section,
2332 unsigned char* view,
2333 typename elfcpp::Elf_types<32>::Elf_Addr
2335 section_size_type view_size,
2336 unsigned char* preloc_out);
2338 // Return whether SYM is defined by the ABI.
2340 do_is_defined_by_abi(Symbol* sym) const
2341 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2343 // Return whether there is a GOT section.
2345 has_got_section() const
2346 { return this->got_ != NULL; }
2348 // Return the size of the GOT section.
2352 gold_assert(this->got_ != NULL);
2353 return this->got_->data_size();
2356 // Return the number of entries in the GOT.
2358 got_entry_count() const
2360 if (!this->has_got_section())
2362 return this->got_size() / 4;
2365 // Return the number of entries in the PLT.
2367 plt_entry_count() const;
2369 // Return the offset of the first non-reserved PLT entry.
2371 first_plt_entry_offset() const;
2373 // Return the size of each PLT entry.
2375 plt_entry_size() const;
2377 // Map platform-specific reloc types
2379 get_real_reloc_type(unsigned int r_type);
2382 // Methods to support stub-generations.
2385 // Return the stub factory
2387 stub_factory() const
2388 { return this->stub_factory_; }
2390 // Make a new Arm_input_section object.
2391 Arm_input_section<big_endian>*
2392 new_arm_input_section(Relobj*, unsigned int);
2394 // Find the Arm_input_section object corresponding to the SHNDX-th input
2395 // section of RELOBJ.
2396 Arm_input_section<big_endian>*
2397 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2399 // Make a new Stub_table
2400 Stub_table<big_endian>*
2401 new_stub_table(Arm_input_section<big_endian>*);
2403 // Scan a section for stub generation.
2405 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2406 const unsigned char*, size_t, Output_section*,
2407 bool, const unsigned char*, Arm_address,
2412 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2413 Output_section*, unsigned char*, Arm_address,
2416 // Get the default ARM target.
2417 static Target_arm<big_endian>*
2420 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2421 && parameters->target().is_big_endian() == big_endian);
2422 return static_cast<Target_arm<big_endian>*>(
2423 parameters->sized_target<32, big_endian>());
2426 // Whether NAME belongs to a mapping symbol.
2428 is_mapping_symbol_name(const char* name)
2432 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2433 && (name[2] == '\0' || name[2] == '.'));
2436 // Whether we work around the Cortex-A8 erratum.
2438 fix_cortex_a8() const
2439 { return this->fix_cortex_a8_; }
2441 // Whether we merge exidx entries in debuginfo.
2443 merge_exidx_entries() const
2444 { return parameters->options().merge_exidx_entries(); }
2446 // Whether we fix R_ARM_V4BX relocation.
2448 // 1 - replace with MOV instruction (armv4 target)
2449 // 2 - make interworking veneer (>= armv4t targets only)
2450 General_options::Fix_v4bx
2452 { return parameters->options().fix_v4bx(); }
2454 // Scan a span of THUMB code section for Cortex-A8 erratum.
2456 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2457 section_size_type, section_size_type,
2458 const unsigned char*, Arm_address);
2460 // Apply Cortex-A8 workaround to a branch.
2462 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2463 unsigned char*, Arm_address);
2466 // Make an ELF object.
2468 do_make_elf_object(const std::string&, Input_file*, off_t,
2469 const elfcpp::Ehdr<32, big_endian>& ehdr);
2472 do_make_elf_object(const std::string&, Input_file*, off_t,
2473 const elfcpp::Ehdr<32, !big_endian>&)
2474 { gold_unreachable(); }
2477 do_make_elf_object(const std::string&, Input_file*, off_t,
2478 const elfcpp::Ehdr<64, false>&)
2479 { gold_unreachable(); }
2482 do_make_elf_object(const std::string&, Input_file*, off_t,
2483 const elfcpp::Ehdr<64, true>&)
2484 { gold_unreachable(); }
2486 // Make an output section.
2488 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2489 elfcpp::Elf_Xword flags)
2490 { return new Arm_output_section<big_endian>(name, type, flags); }
2493 do_adjust_elf_header(unsigned char* view, int len) const;
2495 // We only need to generate stubs, and hence perform relaxation if we are
2496 // not doing relocatable linking.
2498 do_may_relax() const
2499 { return !parameters->options().relocatable(); }
2502 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
2504 // Determine whether an object attribute tag takes an integer, a
2507 do_attribute_arg_type(int tag) const;
2509 // Reorder tags during output.
2511 do_attributes_order(int num) const;
2513 // This is called when the target is selected as the default.
2515 do_select_as_default_target()
2517 // No locking is required since there should only be one default target.
2518 // We cannot have both the big-endian and little-endian ARM targets
2520 gold_assert(arm_reloc_property_table == NULL);
2521 arm_reloc_property_table = new Arm_reloc_property_table();
2525 // The class which scans relocations.
2530 : issued_non_pic_error_(false)
2534 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2535 Sized_relobj<32, big_endian>* object,
2536 unsigned int data_shndx,
2537 Output_section* output_section,
2538 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2539 const elfcpp::Sym<32, big_endian>& lsym);
2542 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2543 Sized_relobj<32, big_endian>* object,
2544 unsigned int data_shndx,
2545 Output_section* output_section,
2546 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2550 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2551 Sized_relobj<32, big_endian>* ,
2554 const elfcpp::Rel<32, big_endian>& ,
2556 const elfcpp::Sym<32, big_endian>&);
2559 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2560 Sized_relobj<32, big_endian>* ,
2563 const elfcpp::Rel<32, big_endian>& ,
2564 unsigned int , Symbol*);
2568 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
2569 unsigned int r_type);
2572 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
2573 unsigned int r_type, Symbol*);
2576 check_non_pic(Relobj*, unsigned int r_type);
2578 // Almost identical to Symbol::needs_plt_entry except that it also
2579 // handles STT_ARM_TFUNC.
2581 symbol_needs_plt_entry(const Symbol* sym)
2583 // An undefined symbol from an executable does not need a PLT entry.
2584 if (sym->is_undefined() && !parameters->options().shared())
2587 return (!parameters->doing_static_link()
2588 && (sym->type() == elfcpp::STT_FUNC
2589 || sym->type() == elfcpp::STT_ARM_TFUNC)
2590 && (sym->is_from_dynobj()
2591 || sym->is_undefined()
2592 || sym->is_preemptible()));
2596 possible_function_pointer_reloc(unsigned int r_type);
2598 // Whether we have issued an error about a non-PIC compilation.
2599 bool issued_non_pic_error_;
2602 // The class which implements relocation.
2612 // Return whether the static relocation needs to be applied.
2614 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2617 Output_section* output_section);
2619 // Do a relocation. Return false if the caller should not issue
2620 // any warnings about this relocation.
2622 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2623 Output_section*, size_t relnum,
2624 const elfcpp::Rel<32, big_endian>&,
2625 unsigned int r_type, const Sized_symbol<32>*,
2626 const Symbol_value<32>*,
2627 unsigned char*, Arm_address,
2630 // Return whether we want to pass flag NON_PIC_REF for this
2631 // reloc. This means the relocation type accesses a symbol not via
2634 reloc_is_non_pic(unsigned int r_type)
2638 // These relocation types reference GOT or PLT entries explicitly.
2639 case elfcpp::R_ARM_GOT_BREL:
2640 case elfcpp::R_ARM_GOT_ABS:
2641 case elfcpp::R_ARM_GOT_PREL:
2642 case elfcpp::R_ARM_GOT_BREL12:
2643 case elfcpp::R_ARM_PLT32_ABS:
2644 case elfcpp::R_ARM_TLS_GD32:
2645 case elfcpp::R_ARM_TLS_LDM32:
2646 case elfcpp::R_ARM_TLS_IE32:
2647 case elfcpp::R_ARM_TLS_IE12GP:
2649 // These relocate types may use PLT entries.
2650 case elfcpp::R_ARM_CALL:
2651 case elfcpp::R_ARM_THM_CALL:
2652 case elfcpp::R_ARM_JUMP24:
2653 case elfcpp::R_ARM_THM_JUMP24:
2654 case elfcpp::R_ARM_THM_JUMP19:
2655 case elfcpp::R_ARM_PLT32:
2656 case elfcpp::R_ARM_THM_XPC22:
2657 case elfcpp::R_ARM_PREL31:
2658 case elfcpp::R_ARM_SBREL31:
2667 // Do a TLS relocation.
2668 inline typename Arm_relocate_functions<big_endian>::Status
2669 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2670 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2671 const Sized_symbol<32>*, const Symbol_value<32>*,
2672 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2677 // A class which returns the size required for a relocation type,
2678 // used while scanning relocs during a relocatable link.
2679 class Relocatable_size_for_reloc
2683 get_size_for_reloc(unsigned int, Relobj*);
2686 // Adjust TLS relocation type based on the options and whether this
2687 // is a local symbol.
2688 static tls::Tls_optimization
2689 optimize_tls_reloc(bool is_final, int r_type);
2691 // Get the GOT section, creating it if necessary.
2692 Arm_output_data_got<big_endian>*
2693 got_section(Symbol_table*, Layout*);
2695 // Get the GOT PLT section.
2697 got_plt_section() const
2699 gold_assert(this->got_plt_ != NULL);
2700 return this->got_plt_;
2703 // Create a PLT entry for a global symbol.
2705 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2707 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2709 define_tls_base_symbol(Symbol_table*, Layout*);
2711 // Create a GOT entry for the TLS module index.
2713 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2714 Sized_relobj<32, big_endian>* object);
2716 // Get the PLT section.
2717 const Output_data_plt_arm<big_endian>*
2720 gold_assert(this->plt_ != NULL);
2724 // Get the dynamic reloc section, creating it if necessary.
2726 rel_dyn_section(Layout*);
2728 // Get the section to use for TLS_DESC relocations.
2730 rel_tls_desc_section(Layout*) const;
2732 // Return true if the symbol may need a COPY relocation.
2733 // References from an executable object to non-function symbols
2734 // defined in a dynamic object may need a COPY relocation.
2736 may_need_copy_reloc(Symbol* gsym)
2738 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2739 && gsym->may_need_copy_reloc());
2742 // Add a potential copy relocation.
2744 copy_reloc(Symbol_table* symtab, Layout* layout,
2745 Sized_relobj<32, big_endian>* object,
2746 unsigned int shndx, Output_section* output_section,
2747 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2749 this->copy_relocs_.copy_reloc(symtab, layout,
2750 symtab->get_sized_symbol<32>(sym),
2751 object, shndx, output_section, reloc,
2752 this->rel_dyn_section(layout));
2755 // Whether two EABI versions are compatible.
2757 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2759 // Merge processor-specific flags from input object and those in the ELF
2760 // header of the output.
2762 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2764 // Get the secondary compatible architecture.
2766 get_secondary_compatible_arch(const Attributes_section_data*);
2768 // Set the secondary compatible architecture.
2770 set_secondary_compatible_arch(Attributes_section_data*, int);
2773 tag_cpu_arch_combine(const char*, int, int*, int, int);
2775 // Helper to print AEABI enum tag value.
2777 aeabi_enum_name(unsigned int);
2779 // Return string value for TAG_CPU_name.
2781 tag_cpu_name_value(unsigned int);
2783 // Merge object attributes from input object and those in the output.
2785 merge_object_attributes(const char*, const Attributes_section_data*);
2787 // Helper to get an AEABI object attribute
2789 get_aeabi_object_attribute(int tag) const
2791 Attributes_section_data* pasd = this->attributes_section_data_;
2792 gold_assert(pasd != NULL);
2793 Object_attribute* attr =
2794 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2795 gold_assert(attr != NULL);
2800 // Methods to support stub-generations.
2803 // Group input sections for stub generation.
2805 group_sections(Layout*, section_size_type, bool);
2807 // Scan a relocation for stub generation.
2809 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2810 const Sized_symbol<32>*, unsigned int,
2811 const Symbol_value<32>*,
2812 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2814 // Scan a relocation section for stub.
2815 template<int sh_type>
2817 scan_reloc_section_for_stubs(
2818 const Relocate_info<32, big_endian>* relinfo,
2819 const unsigned char* prelocs,
2821 Output_section* output_section,
2822 bool needs_special_offset_handling,
2823 const unsigned char* view,
2824 elfcpp::Elf_types<32>::Elf_Addr view_address,
2827 // Fix .ARM.exidx section coverage.
2829 fix_exidx_coverage(Layout*, const Input_objects*,
2830 Arm_output_section<big_endian>*, Symbol_table*);
2832 // Functors for STL set.
2833 struct output_section_address_less_than
2836 operator()(const Output_section* s1, const Output_section* s2) const
2837 { return s1->address() < s2->address(); }
2840 // Information about this specific target which we pass to the
2841 // general Target structure.
2842 static const Target::Target_info arm_info;
2844 // The types of GOT entries needed for this platform.
2845 // These values are exposed to the ABI in an incremental link.
2846 // Do not renumber existing values without changing the version
2847 // number of the .gnu_incremental_inputs section.
2850 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2851 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2852 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2853 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2854 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2857 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2859 // Map input section to Arm_input_section.
2860 typedef Unordered_map<Section_id,
2861 Arm_input_section<big_endian>*,
2863 Arm_input_section_map;
2865 // Map output addresses to relocs for Cortex-A8 erratum.
2866 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2867 Cortex_a8_relocs_info;
2870 Arm_output_data_got<big_endian>* got_;
2872 Output_data_plt_arm<big_endian>* plt_;
2873 // The GOT PLT section.
2874 Output_data_space* got_plt_;
2875 // The dynamic reloc section.
2876 Reloc_section* rel_dyn_;
2877 // Relocs saved to avoid a COPY reloc.
2878 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2879 // Space for variables copied with a COPY reloc.
2880 Output_data_space* dynbss_;
2881 // Offset of the GOT entry for the TLS module index.
2882 unsigned int got_mod_index_offset_;
2883 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2884 bool tls_base_symbol_defined_;
2885 // Vector of Stub_tables created.
2886 Stub_table_list stub_tables_;
2888 const Stub_factory &stub_factory_;
2889 // Whether we can use BLX.
2891 // Whether we force PIC branch veneers.
2892 bool should_force_pic_veneer_;
2893 // Map for locating Arm_input_sections.
2894 Arm_input_section_map arm_input_section_map_;
2895 // Attributes section data in output.
2896 Attributes_section_data* attributes_section_data_;
2897 // Whether we want to fix code for Cortex-A8 erratum.
2898 bool fix_cortex_a8_;
2899 // Map addresses to relocs for Cortex-A8 erratum.
2900 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2903 template<bool big_endian>
2904 const Target::Target_info Target_arm<big_endian>::arm_info =
2907 big_endian, // is_big_endian
2908 elfcpp::EM_ARM, // machine_code
2909 false, // has_make_symbol
2910 false, // has_resolve
2911 false, // has_code_fill
2912 true, // is_default_stack_executable
2914 "/usr/lib/libc.so.1", // dynamic_linker
2915 0x8000, // default_text_segment_address
2916 0x1000, // abi_pagesize (overridable by -z max-page-size)
2917 0x1000, // common_pagesize (overridable by -z common-page-size)
2918 elfcpp::SHN_UNDEF, // small_common_shndx
2919 elfcpp::SHN_UNDEF, // large_common_shndx
2920 0, // small_common_section_flags
2921 0, // large_common_section_flags
2922 ".ARM.attributes", // attributes_section
2923 "aeabi" // attributes_vendor
2926 // Arm relocate functions class
2929 template<bool big_endian>
2930 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2935 STATUS_OKAY, // No error during relocation.
2936 STATUS_OVERFLOW, // Relocation oveflow.
2937 STATUS_BAD_RELOC // Relocation cannot be applied.
2941 typedef Relocate_functions<32, big_endian> Base;
2942 typedef Arm_relocate_functions<big_endian> This;
2944 // Encoding of imm16 argument for movt and movw ARM instructions
2947 // imm16 := imm4 | imm12
2949 // 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
2950 // +-------+---------------+-------+-------+-----------------------+
2951 // | | |imm4 | |imm12 |
2952 // +-------+---------------+-------+-------+-----------------------+
2954 // Extract the relocation addend from VAL based on the ARM
2955 // instruction encoding described above.
2956 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2957 extract_arm_movw_movt_addend(
2958 typename elfcpp::Swap<32, big_endian>::Valtype val)
2960 // According to the Elf ABI for ARM Architecture the immediate
2961 // field is sign-extended to form the addend.
2962 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
2965 // Insert X into VAL based on the ARM instruction encoding described
2967 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2968 insert_val_arm_movw_movt(
2969 typename elfcpp::Swap<32, big_endian>::Valtype val,
2970 typename elfcpp::Swap<32, big_endian>::Valtype x)
2974 val |= (x & 0xf000) << 4;
2978 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2981 // imm16 := imm4 | i | imm3 | imm8
2983 // 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
2984 // +---------+-+-----------+-------++-+-----+-------+---------------+
2985 // | |i| |imm4 || |imm3 | |imm8 |
2986 // +---------+-+-----------+-------++-+-----+-------+---------------+
2988 // Extract the relocation addend from VAL based on the Thumb2
2989 // instruction encoding described above.
2990 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2991 extract_thumb_movw_movt_addend(
2992 typename elfcpp::Swap<32, big_endian>::Valtype val)
2994 // According to the Elf ABI for ARM Architecture the immediate
2995 // field is sign-extended to form the addend.
2996 return utils::sign_extend<16>(((val >> 4) & 0xf000)
2997 | ((val >> 15) & 0x0800)
2998 | ((val >> 4) & 0x0700)
3002 // Insert X into VAL based on the Thumb2 instruction encoding
3004 static inline typename elfcpp::Swap<32, big_endian>::Valtype
3005 insert_val_thumb_movw_movt(
3006 typename elfcpp::Swap<32, big_endian>::Valtype val,
3007 typename elfcpp::Swap<32, big_endian>::Valtype x)
3010 val |= (x & 0xf000) << 4;
3011 val |= (x & 0x0800) << 15;
3012 val |= (x & 0x0700) << 4;
3013 val |= (x & 0x00ff);
3017 // Calculate the smallest constant Kn for the specified residual.
3018 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3020 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
3026 // Determine the most significant bit in the residual and
3027 // align the resulting value to a 2-bit boundary.
3028 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
3030 // The desired shift is now (msb - 6), or zero, whichever
3032 return (((msb - 6) < 0) ? 0 : (msb - 6));
3035 // Calculate the final residual for the specified group index.
3036 // If the passed group index is less than zero, the method will return
3037 // the value of the specified residual without any change.
3038 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3039 static typename elfcpp::Swap<32, big_endian>::Valtype
3040 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3043 for (int n = 0; n <= group; n++)
3045 // Calculate which part of the value to mask.
3046 uint32_t shift = calc_grp_kn(residual);
3047 // Calculate the residual for the next time around.
3048 residual &= ~(residual & (0xff << shift));
3054 // Calculate the value of Gn for the specified group index.
3055 // We return it in the form of an encoded constant-and-rotation.
3056 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
3057 static typename elfcpp::Swap<32, big_endian>::Valtype
3058 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
3061 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
3064 for (int n = 0; n <= group; n++)
3066 // Calculate which part of the value to mask.
3067 shift = calc_grp_kn(residual);
3068 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
3069 gn = residual & (0xff << shift);
3070 // Calculate the residual for the next time around.
3073 // Return Gn in the form of an encoded constant-and-rotation.
3074 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
3078 // Handle ARM long branches.
3079 static typename This::Status
3080 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3081 unsigned char*, const Sized_symbol<32>*,
3082 const Arm_relobj<big_endian>*, unsigned int,
3083 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3085 // Handle THUMB long branches.
3086 static typename This::Status
3087 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
3088 unsigned char*, const Sized_symbol<32>*,
3089 const Arm_relobj<big_endian>*, unsigned int,
3090 const Symbol_value<32>*, Arm_address, Arm_address, bool);
3093 // Return the branch offset of a 32-bit THUMB branch.
3094 static inline int32_t
3095 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3097 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
3098 // involving the J1 and J2 bits.
3099 uint32_t s = (upper_insn & (1U << 10)) >> 10;
3100 uint32_t upper = upper_insn & 0x3ffU;
3101 uint32_t lower = lower_insn & 0x7ffU;
3102 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
3103 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
3104 uint32_t i1 = j1 ^ s ? 0 : 1;
3105 uint32_t i2 = j2 ^ s ? 0 : 1;
3107 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
3108 | (upper << 12) | (lower << 1));
3111 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
3112 // UPPER_INSN is the original upper instruction of the branch. Caller is
3113 // responsible for overflow checking and BLX offset adjustment.
3114 static inline uint16_t
3115 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
3117 uint32_t s = offset < 0 ? 1 : 0;
3118 uint32_t bits = static_cast<uint32_t>(offset);
3119 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
3122 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
3123 // LOWER_INSN is the original lower instruction of the branch. Caller is
3124 // responsible for overflow checking and BLX offset adjustment.
3125 static inline uint16_t
3126 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
3128 uint32_t s = offset < 0 ? 1 : 0;
3129 uint32_t bits = static_cast<uint32_t>(offset);
3130 return ((lower_insn & ~0x2fffU)
3131 | ((((bits >> 23) & 1) ^ !s) << 13)
3132 | ((((bits >> 22) & 1) ^ !s) << 11)
3133 | ((bits >> 1) & 0x7ffU));
3136 // Return the branch offset of a 32-bit THUMB conditional branch.
3137 static inline int32_t
3138 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
3140 uint32_t s = (upper_insn & 0x0400U) >> 10;
3141 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
3142 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
3143 uint32_t lower = (lower_insn & 0x07ffU);
3144 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
3146 return utils::sign_extend<21>((upper << 12) | (lower << 1));
3149 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
3150 // instruction. UPPER_INSN is the original upper instruction of the branch.
3151 // Caller is responsible for overflow checking.
3152 static inline uint16_t
3153 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
3155 uint32_t s = offset < 0 ? 1 : 0;
3156 uint32_t bits = static_cast<uint32_t>(offset);
3157 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
3160 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
3161 // instruction. LOWER_INSN is the original lower instruction of the branch.
3162 // Caller is reponsible for overflow checking.
3163 static inline uint16_t
3164 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
3166 uint32_t bits = static_cast<uint32_t>(offset);
3167 uint32_t j2 = (bits & 0x00080000U) >> 19;
3168 uint32_t j1 = (bits & 0x00040000U) >> 18;
3169 uint32_t lo = (bits & 0x00000ffeU) >> 1;
3171 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
3174 // R_ARM_ABS8: S + A
3175 static inline typename This::Status
3176 abs8(unsigned char* view,
3177 const Sized_relobj<32, big_endian>* object,
3178 const Symbol_value<32>* psymval)
3180 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
3181 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3182 Valtype* wv = reinterpret_cast<Valtype*>(view);
3183 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
3184 Reltype addend = utils::sign_extend<8>(val);
3185 Reltype x = psymval->value(object, addend);
3186 val = utils::bit_select(val, x, 0xffU);
3187 elfcpp::Swap<8, big_endian>::writeval(wv, val);
3189 // R_ARM_ABS8 permits signed or unsigned results.
3190 int signed_x = static_cast<int32_t>(x);
3191 return ((signed_x < -128 || signed_x > 255)
3192 ? This::STATUS_OVERFLOW
3193 : This::STATUS_OKAY);
3196 // R_ARM_THM_ABS5: S + A
3197 static inline typename This::Status
3198 thm_abs5(unsigned char* view,
3199 const Sized_relobj<32, big_endian>* object,
3200 const Symbol_value<32>* psymval)
3202 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3203 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3204 Valtype* wv = reinterpret_cast<Valtype*>(view);
3205 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3206 Reltype addend = (val & 0x7e0U) >> 6;
3207 Reltype x = psymval->value(object, addend);
3208 val = utils::bit_select(val, x << 6, 0x7e0U);
3209 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3211 // R_ARM_ABS16 permits signed or unsigned results.
3212 int signed_x = static_cast<int32_t>(x);
3213 return ((signed_x < -32768 || signed_x > 65535)
3214 ? This::STATUS_OVERFLOW
3215 : This::STATUS_OKAY);
3218 // R_ARM_ABS12: S + A
3219 static inline typename This::Status
3220 abs12(unsigned char* view,
3221 const Sized_relobj<32, big_endian>* object,
3222 const Symbol_value<32>* psymval)
3224 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3225 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3226 Valtype* wv = reinterpret_cast<Valtype*>(view);
3227 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3228 Reltype addend = val & 0x0fffU;
3229 Reltype x = psymval->value(object, addend);
3230 val = utils::bit_select(val, x, 0x0fffU);
3231 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3232 return (utils::has_overflow<12>(x)
3233 ? This::STATUS_OVERFLOW
3234 : This::STATUS_OKAY);
3237 // R_ARM_ABS16: S + A
3238 static inline typename This::Status
3239 abs16(unsigned char* view,
3240 const Sized_relobj<32, big_endian>* object,
3241 const Symbol_value<32>* psymval)
3243 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3244 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3245 Valtype* wv = reinterpret_cast<Valtype*>(view);
3246 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3247 Reltype addend = utils::sign_extend<16>(val);
3248 Reltype x = psymval->value(object, addend);
3249 val = utils::bit_select(val, x, 0xffffU);
3250 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3251 return (utils::has_signed_unsigned_overflow<16>(x)
3252 ? This::STATUS_OVERFLOW
3253 : This::STATUS_OKAY);
3256 // R_ARM_ABS32: (S + A) | T
3257 static inline typename This::Status
3258 abs32(unsigned char* view,
3259 const Sized_relobj<32, big_endian>* object,
3260 const Symbol_value<32>* psymval,
3261 Arm_address thumb_bit)
3263 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3264 Valtype* wv = reinterpret_cast<Valtype*>(view);
3265 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3266 Valtype x = psymval->value(object, addend) | thumb_bit;
3267 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3268 return This::STATUS_OKAY;
3271 // R_ARM_REL32: (S + A) | T - P
3272 static inline typename This::Status
3273 rel32(unsigned char* view,
3274 const Sized_relobj<32, big_endian>* object,
3275 const Symbol_value<32>* psymval,
3276 Arm_address address,
3277 Arm_address thumb_bit)
3279 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3280 Valtype* wv = reinterpret_cast<Valtype*>(view);
3281 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3282 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3283 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3284 return This::STATUS_OKAY;
3287 // R_ARM_THM_JUMP24: (S + A) | T - P
3288 static typename This::Status
3289 thm_jump19(unsigned char* view, const Arm_relobj<big_endian>* object,
3290 const Symbol_value<32>* psymval, Arm_address address,
3291 Arm_address thumb_bit);
3293 // R_ARM_THM_JUMP6: S + A – P
3294 static inline typename This::Status
3295 thm_jump6(unsigned char* view,
3296 const Sized_relobj<32, big_endian>* object,
3297 const Symbol_value<32>* psymval,
3298 Arm_address address)
3300 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3301 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3302 Valtype* wv = reinterpret_cast<Valtype*>(view);
3303 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3304 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3305 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3306 Reltype x = (psymval->value(object, addend) - address);
3307 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3308 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3309 // CZB does only forward jumps.
3310 return ((x > 0x007e)
3311 ? This::STATUS_OVERFLOW
3312 : This::STATUS_OKAY);
3315 // R_ARM_THM_JUMP8: S + A – P
3316 static inline typename This::Status
3317 thm_jump8(unsigned char* view,
3318 const Sized_relobj<32, big_endian>* object,
3319 const Symbol_value<32>* psymval,
3320 Arm_address address)
3322 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3323 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3324 Valtype* wv = reinterpret_cast<Valtype*>(view);
3325 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3326 Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
3327 Reltype x = (psymval->value(object, addend) - address);
3328 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
3329 return (utils::has_overflow<8>(x)
3330 ? This::STATUS_OVERFLOW
3331 : This::STATUS_OKAY);
3334 // R_ARM_THM_JUMP11: S + A – P
3335 static inline typename This::Status
3336 thm_jump11(unsigned char* view,
3337 const Sized_relobj<32, big_endian>* object,
3338 const Symbol_value<32>* psymval,
3339 Arm_address address)
3341 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3342 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3343 Valtype* wv = reinterpret_cast<Valtype*>(view);
3344 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3345 Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
3346 Reltype x = (psymval->value(object, addend) - address);
3347 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
3348 return (utils::has_overflow<11>(x)
3349 ? This::STATUS_OVERFLOW
3350 : This::STATUS_OKAY);
3353 // R_ARM_BASE_PREL: B(S) + A - P
3354 static inline typename This::Status
3355 base_prel(unsigned char* view,
3357 Arm_address address)
3359 Base::rel32(view, origin - address);
3363 // R_ARM_BASE_ABS: B(S) + A
3364 static inline typename This::Status
3365 base_abs(unsigned char* view,
3368 Base::rel32(view, origin);
3372 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3373 static inline typename This::Status
3374 got_brel(unsigned char* view,
3375 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3377 Base::rel32(view, got_offset);
3378 return This::STATUS_OKAY;
3381 // R_ARM_GOT_PREL: GOT(S) + A - P
3382 static inline typename This::Status
3383 got_prel(unsigned char* view,
3384 Arm_address got_entry,
3385 Arm_address address)
3387 Base::rel32(view, got_entry - address);
3388 return This::STATUS_OKAY;
3391 // R_ARM_PREL: (S + A) | T - P
3392 static inline typename This::Status
3393 prel31(unsigned char* view,
3394 const Sized_relobj<32, big_endian>* object,
3395 const Symbol_value<32>* psymval,
3396 Arm_address address,
3397 Arm_address thumb_bit)
3399 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3400 Valtype* wv = reinterpret_cast<Valtype*>(view);
3401 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3402 Valtype addend = utils::sign_extend<31>(val);
3403 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3404 val = utils::bit_select(val, x, 0x7fffffffU);
3405 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3406 return (utils::has_overflow<31>(x) ?
3407 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3410 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3411 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3412 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3413 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3414 static inline typename This::Status
3415 movw(unsigned char* view,
3416 const Sized_relobj<32, big_endian>* object,
3417 const Symbol_value<32>* psymval,
3418 Arm_address relative_address_base,
3419 Arm_address thumb_bit,
3420 bool check_overflow)
3422 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3423 Valtype* wv = reinterpret_cast<Valtype*>(view);
3424 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3425 Valtype addend = This::extract_arm_movw_movt_addend(val);
3426 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3427 - relative_address_base);
3428 val = This::insert_val_arm_movw_movt(val, x);
3429 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3430 return ((check_overflow && utils::has_overflow<16>(x))
3431 ? This::STATUS_OVERFLOW
3432 : This::STATUS_OKAY);
3435 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3436 // R_ARM_MOVT_PREL: S + A - P
3437 // R_ARM_MOVT_BREL: S + A - B(S)
3438 static inline typename This::Status
3439 movt(unsigned char* view,
3440 const Sized_relobj<32, big_endian>* object,
3441 const Symbol_value<32>* psymval,
3442 Arm_address relative_address_base)
3444 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3445 Valtype* wv = reinterpret_cast<Valtype*>(view);
3446 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3447 Valtype addend = This::extract_arm_movw_movt_addend(val);
3448 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3449 val = This::insert_val_arm_movw_movt(val, x);
3450 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3451 // FIXME: IHI0044D says that we should check for overflow.
3452 return This::STATUS_OKAY;
3455 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3456 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3457 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3458 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3459 static inline typename This::Status
3460 thm_movw(unsigned char* view,
3461 const Sized_relobj<32, big_endian>* object,
3462 const Symbol_value<32>* psymval,
3463 Arm_address relative_address_base,
3464 Arm_address thumb_bit,
3465 bool check_overflow)
3467 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3468 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3469 Valtype* wv = reinterpret_cast<Valtype*>(view);
3470 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3471 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3472 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3474 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3475 val = This::insert_val_thumb_movw_movt(val, x);
3476 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3477 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3478 return ((check_overflow && utils::has_overflow<16>(x))
3479 ? This::STATUS_OVERFLOW
3480 : This::STATUS_OKAY);
3483 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3484 // R_ARM_THM_MOVT_PREL: S + A - P
3485 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3486 static inline typename This::Status
3487 thm_movt(unsigned char* view,
3488 const Sized_relobj<32, big_endian>* object,
3489 const Symbol_value<32>* psymval,
3490 Arm_address relative_address_base)
3492 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3493 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3494 Valtype* wv = reinterpret_cast<Valtype*>(view);
3495 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3496 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3497 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3498 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3499 val = This::insert_val_thumb_movw_movt(val, x);
3500 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3501 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3502 return This::STATUS_OKAY;
3505 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3506 static inline typename This::Status
3507 thm_alu11(unsigned char* view,
3508 const Sized_relobj<32, big_endian>* object,
3509 const Symbol_value<32>* psymval,
3510 Arm_address address,
3511 Arm_address thumb_bit)
3513 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3514 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3515 Valtype* wv = reinterpret_cast<Valtype*>(view);
3516 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3517 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3519 // 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
3520 // -----------------------------------------------------------------------
3521 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3522 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3523 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3524 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3525 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3526 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3528 // Determine a sign for the addend.
3529 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3530 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3531 // Thumb2 addend encoding:
3532 // imm12 := i | imm3 | imm8
3533 int32_t addend = (insn & 0xff)
3534 | ((insn & 0x00007000) >> 4)
3535 | ((insn & 0x04000000) >> 15);
3536 // Apply a sign to the added.
3539 int32_t x = (psymval->value(object, addend) | thumb_bit)
3540 - (address & 0xfffffffc);
3541 Reltype val = abs(x);
3542 // Mask out the value and a distinct part of the ADD/SUB opcode
3543 // (bits 7:5 of opword).
3544 insn = (insn & 0xfb0f8f00)
3546 | ((val & 0x700) << 4)
3547 | ((val & 0x800) << 15);
3548 // Set the opcode according to whether the value to go in the
3549 // place is negative.
3553 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3554 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3555 return ((val > 0xfff) ?
3556 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3559 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3560 static inline typename This::Status
3561 thm_pc8(unsigned char* view,
3562 const Sized_relobj<32, big_endian>* object,
3563 const Symbol_value<32>* psymval,
3564 Arm_address address)
3566 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3567 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3568 Valtype* wv = reinterpret_cast<Valtype*>(view);
3569 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3570 Reltype addend = ((insn & 0x00ff) << 2);
3571 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3572 Reltype val = abs(x);
3573 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3575 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3576 return ((val > 0x03fc)
3577 ? This::STATUS_OVERFLOW
3578 : This::STATUS_OKAY);
3581 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3582 static inline typename This::Status
3583 thm_pc12(unsigned char* view,
3584 const Sized_relobj<32, big_endian>* object,
3585 const Symbol_value<32>* psymval,
3586 Arm_address address)
3588 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3589 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3590 Valtype* wv = reinterpret_cast<Valtype*>(view);
3591 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3592 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3593 // Determine a sign for the addend (positive if the U bit is 1).
3594 const int sign = (insn & 0x00800000) ? 1 : -1;
3595 int32_t addend = (insn & 0xfff);
3596 // Apply a sign to the added.
3599 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3600 Reltype val = abs(x);
3601 // Mask out and apply the value and the U bit.
3602 insn = (insn & 0xff7ff000) | (val & 0xfff);
3603 // Set the U bit according to whether the value to go in the
3604 // place is positive.
3608 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3609 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3610 return ((val > 0xfff) ?
3611 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3615 static inline typename This::Status
3616 v4bx(const Relocate_info<32, big_endian>* relinfo,
3617 unsigned char* view,
3618 const Arm_relobj<big_endian>* object,
3619 const Arm_address address,
3620 const bool is_interworking)
3623 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3624 Valtype* wv = reinterpret_cast<Valtype*>(view);
3625 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3627 // Ensure that we have a BX instruction.
3628 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3629 const uint32_t reg = (val & 0xf);
3630 if (is_interworking && reg != 0xf)
3632 Stub_table<big_endian>* stub_table =
3633 object->stub_table(relinfo->data_shndx);
3634 gold_assert(stub_table != NULL);
3636 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3637 gold_assert(stub != NULL);
3639 int32_t veneer_address =
3640 stub_table->address() + stub->offset() - 8 - address;
3641 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3642 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3643 // Replace with a branch to veneer (B <addr>)
3644 val = (val & 0xf0000000) | 0x0a000000
3645 | ((veneer_address >> 2) & 0x00ffffff);
3649 // Preserve Rm (lowest four bits) and the condition code
3650 // (highest four bits). Other bits encode MOV PC,Rm.
3651 val = (val & 0xf000000f) | 0x01a0f000;
3653 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3654 return This::STATUS_OKAY;
3657 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3658 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3659 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3660 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3661 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3662 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3663 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3664 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3665 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3666 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3667 static inline typename This::Status
3668 arm_grp_alu(unsigned char* view,
3669 const Sized_relobj<32, big_endian>* object,
3670 const Symbol_value<32>* psymval,
3672 Arm_address address,
3673 Arm_address thumb_bit,
3674 bool check_overflow)
3676 gold_assert(group >= 0 && group < 3);
3677 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3678 Valtype* wv = reinterpret_cast<Valtype*>(view);
3679 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3681 // ALU group relocations are allowed only for the ADD/SUB instructions.
3682 // (0x00800000 - ADD, 0x00400000 - SUB)
3683 const Valtype opcode = insn & 0x01e00000;
3684 if (opcode != 0x00800000 && opcode != 0x00400000)
3685 return This::STATUS_BAD_RELOC;
3687 // Determine a sign for the addend.
3688 const int sign = (opcode == 0x00800000) ? 1 : -1;
3689 // shifter = rotate_imm * 2
3690 const uint32_t shifter = (insn & 0xf00) >> 7;
3691 // Initial addend value.
3692 int32_t addend = insn & 0xff;
3693 // Rotate addend right by shifter.
3694 addend = (addend >> shifter) | (addend << (32 - shifter));
3695 // Apply a sign to the added.
3698 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3699 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3700 // Check for overflow if required
3702 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3703 return This::STATUS_OVERFLOW;
3705 // Mask out the value and the ADD/SUB part of the opcode; take care
3706 // not to destroy the S bit.
3708 // Set the opcode according to whether the value to go in the
3709 // place is negative.
3710 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3711 // Encode the offset (encoded Gn).
3714 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3715 return This::STATUS_OKAY;
3718 // R_ARM_LDR_PC_G0: S + A - P
3719 // R_ARM_LDR_PC_G1: S + A - P
3720 // R_ARM_LDR_PC_G2: S + A - P
3721 // R_ARM_LDR_SB_G0: S + A - B(S)
3722 // R_ARM_LDR_SB_G1: S + A - B(S)
3723 // R_ARM_LDR_SB_G2: S + A - B(S)
3724 static inline typename This::Status
3725 arm_grp_ldr(unsigned char* view,
3726 const Sized_relobj<32, big_endian>* object,
3727 const Symbol_value<32>* psymval,
3729 Arm_address address)
3731 gold_assert(group >= 0 && group < 3);
3732 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3733 Valtype* wv = reinterpret_cast<Valtype*>(view);
3734 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3736 const int sign = (insn & 0x00800000) ? 1 : -1;
3737 int32_t addend = (insn & 0xfff) * sign;
3738 int32_t x = (psymval->value(object, addend) - address);
3739 // Calculate the relevant G(n-1) value to obtain this stage residual.
3741 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3742 if (residual >= 0x1000)
3743 return This::STATUS_OVERFLOW;
3745 // Mask out the value and U bit.
3747 // Set the U bit for non-negative values.
3752 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3753 return This::STATUS_OKAY;
3756 // R_ARM_LDRS_PC_G0: S + A - P
3757 // R_ARM_LDRS_PC_G1: S + A - P
3758 // R_ARM_LDRS_PC_G2: S + A - P
3759 // R_ARM_LDRS_SB_G0: S + A - B(S)
3760 // R_ARM_LDRS_SB_G1: S + A - B(S)
3761 // R_ARM_LDRS_SB_G2: S + A - B(S)
3762 static inline typename This::Status
3763 arm_grp_ldrs(unsigned char* view,
3764 const Sized_relobj<32, big_endian>* object,
3765 const Symbol_value<32>* psymval,
3767 Arm_address address)
3769 gold_assert(group >= 0 && group < 3);
3770 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3771 Valtype* wv = reinterpret_cast<Valtype*>(view);
3772 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3774 const int sign = (insn & 0x00800000) ? 1 : -1;
3775 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3776 int32_t x = (psymval->value(object, addend) - address);
3777 // Calculate the relevant G(n-1) value to obtain this stage residual.
3779 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3780 if (residual >= 0x100)
3781 return This::STATUS_OVERFLOW;
3783 // Mask out the value and U bit.
3785 // Set the U bit for non-negative values.
3788 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3790 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3791 return This::STATUS_OKAY;
3794 // R_ARM_LDC_PC_G0: S + A - P
3795 // R_ARM_LDC_PC_G1: S + A - P
3796 // R_ARM_LDC_PC_G2: S + A - P
3797 // R_ARM_LDC_SB_G0: S + A - B(S)
3798 // R_ARM_LDC_SB_G1: S + A - B(S)
3799 // R_ARM_LDC_SB_G2: S + A - B(S)
3800 static inline typename This::Status
3801 arm_grp_ldc(unsigned char* view,
3802 const Sized_relobj<32, big_endian>* object,
3803 const Symbol_value<32>* psymval,
3805 Arm_address address)
3807 gold_assert(group >= 0 && group < 3);
3808 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3809 Valtype* wv = reinterpret_cast<Valtype*>(view);
3810 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3812 const int sign = (insn & 0x00800000) ? 1 : -1;
3813 int32_t addend = ((insn & 0xff) << 2) * sign;
3814 int32_t x = (psymval->value(object, addend) - address);
3815 // Calculate the relevant G(n-1) value to obtain this stage residual.
3817 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3818 if ((residual & 0x3) != 0 || residual >= 0x400)
3819 return This::STATUS_OVERFLOW;
3821 // Mask out the value and U bit.
3823 // Set the U bit for non-negative values.
3826 insn |= (residual >> 2);
3828 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3829 return This::STATUS_OKAY;
3833 // Relocate ARM long branches. This handles relocation types
3834 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3835 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3836 // undefined and we do not use PLT in this relocation. In such a case,
3837 // the branch is converted into an NOP.
3839 template<bool big_endian>
3840 typename Arm_relocate_functions<big_endian>::Status
3841 Arm_relocate_functions<big_endian>::arm_branch_common(
3842 unsigned int r_type,
3843 const Relocate_info<32, big_endian>* relinfo,
3844 unsigned char* view,
3845 const Sized_symbol<32>* gsym,
3846 const Arm_relobj<big_endian>* object,
3848 const Symbol_value<32>* psymval,
3849 Arm_address address,
3850 Arm_address thumb_bit,
3851 bool is_weakly_undefined_without_plt)
3853 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3854 Valtype* wv = reinterpret_cast<Valtype*>(view);
3855 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3857 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3858 && ((val & 0x0f000000UL) == 0x0a000000UL);
3859 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3860 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3861 && ((val & 0x0f000000UL) == 0x0b000000UL);
3862 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3863 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3865 // Check that the instruction is valid.
3866 if (r_type == elfcpp::R_ARM_CALL)
3868 if (!insn_is_uncond_bl && !insn_is_blx)
3869 return This::STATUS_BAD_RELOC;
3871 else if (r_type == elfcpp::R_ARM_JUMP24)
3873 if (!insn_is_b && !insn_is_cond_bl)
3874 return This::STATUS_BAD_RELOC;
3876 else if (r_type == elfcpp::R_ARM_PLT32)
3878 if (!insn_is_any_branch)
3879 return This::STATUS_BAD_RELOC;
3881 else if (r_type == elfcpp::R_ARM_XPC25)
3883 // FIXME: AAELF document IH0044C does not say much about it other
3884 // than it being obsolete.
3885 if (!insn_is_any_branch)
3886 return This::STATUS_BAD_RELOC;
3891 // A branch to an undefined weak symbol is turned into a jump to
3892 // the next instruction unless a PLT entry will be created.
3893 // Do the same for local undefined symbols.
3894 // The jump to the next instruction is optimized as a NOP depending
3895 // on the architecture.
3896 const Target_arm<big_endian>* arm_target =
3897 Target_arm<big_endian>::default_target();
3898 if (is_weakly_undefined_without_plt)
3900 gold_assert(!parameters->options().relocatable());
3901 Valtype cond = val & 0xf0000000U;
3902 if (arm_target->may_use_arm_nop())
3903 val = cond | 0x0320f000;
3905 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3906 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3907 return This::STATUS_OKAY;
3910 Valtype addend = utils::sign_extend<26>(val << 2);
3911 Valtype branch_target = psymval->value(object, addend);
3912 int32_t branch_offset = branch_target - address;
3914 // We need a stub if the branch offset is too large or if we need
3916 bool may_use_blx = arm_target->may_use_blx();
3917 Reloc_stub* stub = NULL;
3919 if (!parameters->options().relocatable()
3920 && (utils::has_overflow<26>(branch_offset)
3921 || ((thumb_bit != 0)
3922 && !(may_use_blx && r_type == elfcpp::R_ARM_CALL))))
3924 Valtype unadjusted_branch_target = psymval->value(object, 0);
3926 Stub_type stub_type =
3927 Reloc_stub::stub_type_for_reloc(r_type, address,
3928 unadjusted_branch_target,
3930 if (stub_type != arm_stub_none)
3932 Stub_table<big_endian>* stub_table =
3933 object->stub_table(relinfo->data_shndx);
3934 gold_assert(stub_table != NULL);
3936 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3937 stub = stub_table->find_reloc_stub(stub_key);
3938 gold_assert(stub != NULL);
3939 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3940 branch_target = stub_table->address() + stub->offset() + addend;
3941 branch_offset = branch_target - address;
3942 gold_assert(!utils::has_overflow<26>(branch_offset));
3946 // At this point, if we still need to switch mode, the instruction
3947 // must either be a BLX or a BL that can be converted to a BLX.
3951 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3952 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3955 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
3956 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3957 return (utils::has_overflow<26>(branch_offset)
3958 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
3961 // Relocate THUMB long branches. This handles relocation types
3962 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3963 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3964 // undefined and we do not use PLT in this relocation. In such a case,
3965 // the branch is converted into an NOP.
3967 template<bool big_endian>
3968 typename Arm_relocate_functions<big_endian>::Status
3969 Arm_relocate_functions<big_endian>::thumb_branch_common(
3970 unsigned int r_type,
3971 const Relocate_info<32, big_endian>* relinfo,
3972 unsigned char* view,
3973 const Sized_symbol<32>* gsym,
3974 const Arm_relobj<big_endian>* object,
3976 const Symbol_value<32>* psymval,
3977 Arm_address address,
3978 Arm_address thumb_bit,
3979 bool is_weakly_undefined_without_plt)
3981 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3982 Valtype* wv = reinterpret_cast<Valtype*>(view);
3983 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3984 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3986 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3988 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
3989 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
3991 // Check that the instruction is valid.
3992 if (r_type == elfcpp::R_ARM_THM_CALL)
3994 if (!is_bl_insn && !is_blx_insn)
3995 return This::STATUS_BAD_RELOC;
3997 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
3999 // This cannot be a BLX.
4001 return This::STATUS_BAD_RELOC;
4003 else if (r_type == elfcpp::R_ARM_THM_XPC22)
4005 // Check for Thumb to Thumb call.
4007 return This::STATUS_BAD_RELOC;
4010 gold_warning(_("%s: Thumb BLX instruction targets "
4011 "thumb function '%s'."),
4012 object->name().c_str(),
4013 (gsym ? gsym->name() : "(local)"));
4014 // Convert BLX to BL.
4015 lower_insn |= 0x1000U;
4021 // A branch to an undefined weak symbol is turned into a jump to
4022 // the next instruction unless a PLT entry will be created.
4023 // The jump to the next instruction is optimized as a NOP.W for
4024 // Thumb-2 enabled architectures.
4025 const Target_arm<big_endian>* arm_target =
4026 Target_arm<big_endian>::default_target();
4027 if (is_weakly_undefined_without_plt)
4029 gold_assert(!parameters->options().relocatable());
4030 if (arm_target->may_use_thumb2_nop())
4032 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
4033 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
4037 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
4038 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
4040 return This::STATUS_OKAY;
4043 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
4044 Arm_address branch_target = psymval->value(object, addend);
4046 // For BLX, bit 1 of target address comes from bit 1 of base address.
4047 bool may_use_blx = arm_target->may_use_blx();
4048 if (thumb_bit == 0 && may_use_blx)
4049 branch_target = utils::bit_select(branch_target, address, 0x2);
4051 int32_t branch_offset = branch_target - address;
4053 // We need a stub if the branch offset is too large or if we need
4055 bool thumb2 = arm_target->using_thumb2();
4056 if (!parameters->options().relocatable()
4057 && ((!thumb2 && utils::has_overflow<23>(branch_offset))
4058 || (thumb2 && utils::has_overflow<25>(branch_offset))
4059 || ((thumb_bit == 0)
4060 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4061 || r_type == elfcpp::R_ARM_THM_JUMP24))))
4063 Arm_address unadjusted_branch_target = psymval->value(object, 0);
4065 Stub_type stub_type =
4066 Reloc_stub::stub_type_for_reloc(r_type, address,
4067 unadjusted_branch_target,
4070 if (stub_type != arm_stub_none)
4072 Stub_table<big_endian>* stub_table =
4073 object->stub_table(relinfo->data_shndx);
4074 gold_assert(stub_table != NULL);
4076 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
4077 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
4078 gold_assert(stub != NULL);
4079 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
4080 branch_target = stub_table->address() + stub->offset() + addend;
4081 if (thumb_bit == 0 && may_use_blx)
4082 branch_target = utils::bit_select(branch_target, address, 0x2);
4083 branch_offset = branch_target - address;
4087 // At this point, if we still need to switch mode, the instruction
4088 // must either be a BLX or a BL that can be converted to a BLX.
4091 gold_assert(may_use_blx
4092 && (r_type == elfcpp::R_ARM_THM_CALL
4093 || r_type == elfcpp::R_ARM_THM_XPC22));
4094 // Make sure this is a BLX.
4095 lower_insn &= ~0x1000U;
4099 // Make sure this is a BL.
4100 lower_insn |= 0x1000U;
4103 // For a BLX instruction, make sure that the relocation is rounded up
4104 // to a word boundary. This follows the semantics of the instruction
4105 // which specifies that bit 1 of the target address will come from bit
4106 // 1 of the base address.
4107 if ((lower_insn & 0x5000U) == 0x4000U)
4108 gold_assert((branch_offset & 3) == 0);
4110 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
4111 // We use the Thumb-2 encoding, which is safe even if dealing with
4112 // a Thumb-1 instruction by virtue of our overflow check above. */
4113 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
4114 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
4116 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4117 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4119 gold_assert(!utils::has_overflow<25>(branch_offset));
4122 ? utils::has_overflow<25>(branch_offset)
4123 : utils::has_overflow<23>(branch_offset))
4124 ? This::STATUS_OVERFLOW
4125 : This::STATUS_OKAY);
4128 // Relocate THUMB-2 long conditional branches.
4129 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
4130 // undefined and we do not use PLT in this relocation. In such a case,
4131 // the branch is converted into an NOP.
4133 template<bool big_endian>
4134 typename Arm_relocate_functions<big_endian>::Status
4135 Arm_relocate_functions<big_endian>::thm_jump19(
4136 unsigned char* view,
4137 const Arm_relobj<big_endian>* object,
4138 const Symbol_value<32>* psymval,
4139 Arm_address address,
4140 Arm_address thumb_bit)
4142 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
4143 Valtype* wv = reinterpret_cast<Valtype*>(view);
4144 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
4145 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
4146 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
4148 Arm_address branch_target = psymval->value(object, addend);
4149 int32_t branch_offset = branch_target - address;
4151 // ??? Should handle interworking? GCC might someday try to
4152 // use this for tail calls.
4153 // FIXME: We do support thumb entry to PLT yet.
4156 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
4157 return This::STATUS_BAD_RELOC;
4160 // Put RELOCATION back into the insn.
4161 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
4162 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
4164 // Put the relocated value back in the object file:
4165 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
4166 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
4168 return (utils::has_overflow<21>(branch_offset)
4169 ? This::STATUS_OVERFLOW
4170 : This::STATUS_OKAY);
4173 // Get the GOT section, creating it if necessary.
4175 template<bool big_endian>
4176 Arm_output_data_got<big_endian>*
4177 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
4179 if (this->got_ == NULL)
4181 gold_assert(symtab != NULL && layout != NULL);
4183 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
4185 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4187 | elfcpp::SHF_WRITE),
4188 this->got_, ORDER_RELRO, true);
4190 // The old GNU linker creates a .got.plt section. We just
4191 // create another set of data in the .got section. Note that we
4192 // always create a PLT if we create a GOT, although the PLT
4194 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
4195 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
4197 | elfcpp::SHF_WRITE),
4198 this->got_plt_, ORDER_DATA, false);
4200 // The first three entries are reserved.
4201 this->got_plt_->set_current_data_size(3 * 4);
4203 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
4204 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
4205 Symbol_table::PREDEFINED,
4207 0, 0, elfcpp::STT_OBJECT,
4209 elfcpp::STV_HIDDEN, 0,
4215 // Get the dynamic reloc section, creating it if necessary.
4217 template<bool big_endian>
4218 typename Target_arm<big_endian>::Reloc_section*
4219 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
4221 if (this->rel_dyn_ == NULL)
4223 gold_assert(layout != NULL);
4224 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
4225 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
4226 elfcpp::SHF_ALLOC, this->rel_dyn_,
4227 ORDER_DYNAMIC_RELOCS, false);
4229 return this->rel_dyn_;
4232 // Insn_template methods.
4234 // Return byte size of an instruction template.
4237 Insn_template::size() const
4239 switch (this->type())
4242 case THUMB16_SPECIAL_TYPE:
4253 // Return alignment of an instruction template.
4256 Insn_template::alignment() const
4258 switch (this->type())
4261 case THUMB16_SPECIAL_TYPE:
4272 // Stub_template methods.
4274 Stub_template::Stub_template(
4275 Stub_type type, const Insn_template* insns,
4277 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4278 entry_in_thumb_mode_(false), relocs_()
4282 // Compute byte size and alignment of stub template.
4283 for (size_t i = 0; i < insn_count; i++)
4285 unsigned insn_alignment = insns[i].alignment();
4286 size_t insn_size = insns[i].size();
4287 gold_assert((offset & (insn_alignment - 1)) == 0);
4288 this->alignment_ = std::max(this->alignment_, insn_alignment);
4289 switch (insns[i].type())
4291 case Insn_template::THUMB16_TYPE:
4292 case Insn_template::THUMB16_SPECIAL_TYPE:
4294 this->entry_in_thumb_mode_ = true;
4297 case Insn_template::THUMB32_TYPE:
4298 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4299 this->relocs_.push_back(Reloc(i, offset));
4301 this->entry_in_thumb_mode_ = true;
4304 case Insn_template::ARM_TYPE:
4305 // Handle cases where the target is encoded within the
4307 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4308 this->relocs_.push_back(Reloc(i, offset));
4311 case Insn_template::DATA_TYPE:
4312 // Entry point cannot be data.
4313 gold_assert(i != 0);
4314 this->relocs_.push_back(Reloc(i, offset));
4320 offset += insn_size;
4322 this->size_ = offset;
4327 // Template to implement do_write for a specific target endianness.
4329 template<bool big_endian>
4331 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4333 const Stub_template* stub_template = this->stub_template();
4334 const Insn_template* insns = stub_template->insns();
4336 // FIXME: We do not handle BE8 encoding yet.
4337 unsigned char* pov = view;
4338 for (size_t i = 0; i < stub_template->insn_count(); i++)
4340 switch (insns[i].type())
4342 case Insn_template::THUMB16_TYPE:
4343 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4345 case Insn_template::THUMB16_SPECIAL_TYPE:
4346 elfcpp::Swap<16, big_endian>::writeval(
4348 this->thumb16_special(i));
4350 case Insn_template::THUMB32_TYPE:
4352 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4353 uint32_t lo = insns[i].data() & 0xffff;
4354 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4355 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4358 case Insn_template::ARM_TYPE:
4359 case Insn_template::DATA_TYPE:
4360 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4365 pov += insns[i].size();
4367 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4370 // Reloc_stub::Key methods.
4372 // Dump a Key as a string for debugging.
4375 Reloc_stub::Key::name() const
4377 if (this->r_sym_ == invalid_index)
4379 // Global symbol key name
4380 // <stub-type>:<symbol name>:<addend>.
4381 const std::string sym_name = this->u_.symbol->name();
4382 // We need to print two hex number and two colons. So just add 100 bytes
4383 // to the symbol name size.
4384 size_t len = sym_name.size() + 100;
4385 char* buffer = new char[len];
4386 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4387 sym_name.c_str(), this->addend_);
4388 gold_assert(c > 0 && c < static_cast<int>(len));
4390 return std::string(buffer);
4394 // local symbol key name
4395 // <stub-type>:<object>:<r_sym>:<addend>.
4396 const size_t len = 200;
4398 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4399 this->u_.relobj, this->r_sym_, this->addend_);
4400 gold_assert(c > 0 && c < static_cast<int>(len));
4401 return std::string(buffer);
4405 // Reloc_stub methods.
4407 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4408 // LOCATION to DESTINATION.
4409 // This code is based on the arm_type_of_stub function in
4410 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
4414 Reloc_stub::stub_type_for_reloc(
4415 unsigned int r_type,
4416 Arm_address location,
4417 Arm_address destination,
4418 bool target_is_thumb)
4420 Stub_type stub_type = arm_stub_none;
4422 // This is a bit ugly but we want to avoid using a templated class for
4423 // big and little endianities.
4425 bool should_force_pic_veneer;
4428 if (parameters->target().is_big_endian())
4430 const Target_arm<true>* big_endian_target =
4431 Target_arm<true>::default_target();
4432 may_use_blx = big_endian_target->may_use_blx();
4433 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4434 thumb2 = big_endian_target->using_thumb2();
4435 thumb_only = big_endian_target->using_thumb_only();
4439 const Target_arm<false>* little_endian_target =
4440 Target_arm<false>::default_target();
4441 may_use_blx = little_endian_target->may_use_blx();
4442 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4443 thumb2 = little_endian_target->using_thumb2();
4444 thumb_only = little_endian_target->using_thumb_only();
4447 int64_t branch_offset;
4448 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4450 // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
4451 // base address (instruction address + 4).
4452 if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
4453 destination = utils::bit_select(destination, location, 0x2);
4454 branch_offset = static_cast<int64_t>(destination) - location;
4456 // Handle cases where:
4457 // - this call goes too far (different Thumb/Thumb2 max
4459 // - it's a Thumb->Arm call and blx is not available, or it's a
4460 // Thumb->Arm branch (not bl). A stub is needed in this case.
4462 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4463 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4465 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4466 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4467 || ((!target_is_thumb)
4468 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4469 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4471 if (target_is_thumb)
4476 stub_type = (parameters->options().shared()
4477 || should_force_pic_veneer)
4480 && (r_type == elfcpp::R_ARM_THM_CALL))
4481 // V5T and above. Stub starts with ARM code, so
4482 // we must be able to switch mode before
4483 // reaching it, which is only possible for 'bl'
4484 // (ie R_ARM_THM_CALL relocation).
4485 ? arm_stub_long_branch_any_thumb_pic
4486 // On V4T, use Thumb code only.
4487 : arm_stub_long_branch_v4t_thumb_thumb_pic)
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_thumb); // V4T.
4497 stub_type = (parameters->options().shared()
4498 || should_force_pic_veneer)
4499 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4500 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4507 // FIXME: We should check that the input section is from an
4508 // object that has interwork enabled.
4510 stub_type = (parameters->options().shared()
4511 || should_force_pic_veneer)
4514 && (r_type == elfcpp::R_ARM_THM_CALL))
4515 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4516 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4520 && (r_type == elfcpp::R_ARM_THM_CALL))
4521 ? arm_stub_long_branch_any_any // V5T and above.
4522 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4524 // Handle v4t short branches.
4525 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4526 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4527 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4528 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4532 else if (r_type == elfcpp::R_ARM_CALL
4533 || r_type == elfcpp::R_ARM_JUMP24
4534 || r_type == elfcpp::R_ARM_PLT32)
4536 branch_offset = static_cast<int64_t>(destination) - location;
4537 if (target_is_thumb)
4541 // FIXME: We should check that the input section is from an
4542 // object that has interwork enabled.
4544 // We have an extra 2-bytes reach because of
4545 // the mode change (bit 24 (H) of BLX encoding).
4546 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4547 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4548 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4549 || (r_type == elfcpp::R_ARM_JUMP24)
4550 || (r_type == elfcpp::R_ARM_PLT32))
4552 stub_type = (parameters->options().shared()
4553 || should_force_pic_veneer)
4556 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4557 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4561 ? arm_stub_long_branch_any_any // V5T and above.
4562 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4568 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4569 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4571 stub_type = (parameters->options().shared()
4572 || should_force_pic_veneer)
4573 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4574 : arm_stub_long_branch_any_any; /// non-PIC.
4582 // Cortex_a8_stub methods.
4584 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4585 // I is the position of the instruction template in the stub template.
4588 Cortex_a8_stub::do_thumb16_special(size_t i)
4590 // The only use of this is to copy condition code from a conditional
4591 // branch being worked around to the corresponding conditional branch in
4593 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4595 uint16_t data = this->stub_template()->insns()[i].data();
4596 gold_assert((data & 0xff00U) == 0xd000U);
4597 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4601 // Stub_factory methods.
4603 Stub_factory::Stub_factory()
4605 // The instruction template sequences are declared as static
4606 // objects and initialized first time the constructor runs.
4608 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4609 // to reach the stub if necessary.
4610 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4612 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4613 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4614 // dcd R_ARM_ABS32(X)
4617 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4619 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4621 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4622 Insn_template::arm_insn(0xe12fff1c), // bx ip
4623 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4624 // dcd R_ARM_ABS32(X)
4627 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4628 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4630 Insn_template::thumb16_insn(0xb401), // push {r0}
4631 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4632 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4633 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4634 Insn_template::thumb16_insn(0x4760), // bx ip
4635 Insn_template::thumb16_insn(0xbf00), // nop
4636 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4637 // dcd R_ARM_ABS32(X)
4640 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4642 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4644 Insn_template::thumb16_insn(0x4778), // bx pc
4645 Insn_template::thumb16_insn(0x46c0), // nop
4646 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4647 Insn_template::arm_insn(0xe12fff1c), // bx ip
4648 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4649 // dcd R_ARM_ABS32(X)
4652 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4654 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4656 Insn_template::thumb16_insn(0x4778), // bx pc
4657 Insn_template::thumb16_insn(0x46c0), // nop
4658 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4659 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4660 // dcd R_ARM_ABS32(X)
4663 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4664 // one, when the destination is close enough.
4665 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4667 Insn_template::thumb16_insn(0x4778), // bx pc
4668 Insn_template::thumb16_insn(0x46c0), // nop
4669 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4672 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4673 // blx to reach the stub if necessary.
4674 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4676 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4677 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4678 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4679 // dcd R_ARM_REL32(X-4)
4682 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4683 // blx to reach the stub if necessary. We can not add into pc;
4684 // it is not guaranteed to mode switch (different in ARMv6 and
4686 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4688 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4689 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4690 Insn_template::arm_insn(0xe12fff1c), // bx ip
4691 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4692 // dcd R_ARM_REL32(X)
4695 // V4T ARM -> ARM long branch stub, PIC.
4696 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4698 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4699 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4700 Insn_template::arm_insn(0xe12fff1c), // bx ip
4701 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4702 // dcd R_ARM_REL32(X)
4705 // V4T Thumb -> ARM long branch stub, PIC.
4706 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4708 Insn_template::thumb16_insn(0x4778), // bx pc
4709 Insn_template::thumb16_insn(0x46c0), // nop
4710 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4711 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4712 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4713 // dcd R_ARM_REL32(X)
4716 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4718 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4720 Insn_template::thumb16_insn(0xb401), // push {r0}
4721 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4722 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4723 Insn_template::thumb16_insn(0x4484), // add ip, r0
4724 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4725 Insn_template::thumb16_insn(0x4760), // bx ip
4726 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4727 // dcd R_ARM_REL32(X)
4730 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4732 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4734 Insn_template::thumb16_insn(0x4778), // bx pc
4735 Insn_template::thumb16_insn(0x46c0), // nop
4736 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4737 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4738 Insn_template::arm_insn(0xe12fff1c), // bx ip
4739 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4740 // dcd R_ARM_REL32(X)
4743 // Cortex-A8 erratum-workaround stubs.
4745 // Stub used for conditional branches (which may be beyond +/-1MB away,
4746 // so we can't use a conditional branch to reach this stub).
4753 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4755 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4756 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4757 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4761 // Stub used for b.w and bl.w instructions.
4763 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4765 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4768 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4770 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4773 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4774 // instruction (which switches to ARM mode) to point to this stub. Jump to
4775 // the real destination using an ARM-mode branch.
4776 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4778 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4781 // Stub used to provide an interworking for R_ARM_V4BX relocation
4782 // (bx r[n] instruction).
4783 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4785 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4786 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4787 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4790 // Fill in the stub template look-up table. Stub templates are constructed
4791 // per instance of Stub_factory for fast look-up without locking
4792 // in a thread-enabled environment.
4794 this->stub_templates_[arm_stub_none] =
4795 new Stub_template(arm_stub_none, NULL, 0);
4797 #define DEF_STUB(x) \
4801 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4802 Stub_type type = arm_stub_##x; \
4803 this->stub_templates_[type] = \
4804 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4812 // Stub_table methods.
4814 // Removel all Cortex-A8 stub.
4816 template<bool big_endian>
4818 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4820 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4821 p != this->cortex_a8_stubs_.end();
4824 this->cortex_a8_stubs_.clear();
4827 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4829 template<bool big_endian>
4831 Stub_table<big_endian>::relocate_stub(
4833 const Relocate_info<32, big_endian>* relinfo,
4834 Target_arm<big_endian>* arm_target,
4835 Output_section* output_section,
4836 unsigned char* view,
4837 Arm_address address,
4838 section_size_type view_size)
4840 const Stub_template* stub_template = stub->stub_template();
4841 if (stub_template->reloc_count() != 0)
4843 // Adjust view to cover the stub only.
4844 section_size_type offset = stub->offset();
4845 section_size_type stub_size = stub_template->size();
4846 gold_assert(offset + stub_size <= view_size);
4848 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4849 address + offset, stub_size);
4853 // Relocate all stubs in this stub table.
4855 template<bool big_endian>
4857 Stub_table<big_endian>::relocate_stubs(
4858 const Relocate_info<32, big_endian>* relinfo,
4859 Target_arm<big_endian>* arm_target,
4860 Output_section* output_section,
4861 unsigned char* view,
4862 Arm_address address,
4863 section_size_type view_size)
4865 // If we are passed a view bigger than the stub table's. we need to
4867 gold_assert(address == this->address()
4869 == static_cast<section_size_type>(this->data_size())));
4871 // Relocate all relocation stubs.
4872 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4873 p != this->reloc_stubs_.end();
4875 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4876 address, view_size);
4878 // Relocate all Cortex-A8 stubs.
4879 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4880 p != this->cortex_a8_stubs_.end();
4882 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4883 address, view_size);
4885 // Relocate all ARM V4BX stubs.
4886 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4887 p != this->arm_v4bx_stubs_.end();
4891 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4892 address, view_size);
4896 // Write out the stubs to file.
4898 template<bool big_endian>
4900 Stub_table<big_endian>::do_write(Output_file* of)
4902 off_t offset = this->offset();
4903 const section_size_type oview_size =
4904 convert_to_section_size_type(this->data_size());
4905 unsigned char* const oview = of->get_output_view(offset, oview_size);
4907 // Write relocation stubs.
4908 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4909 p != this->reloc_stubs_.end();
4912 Reloc_stub* stub = p->second;
4913 Arm_address address = this->address() + stub->offset();
4915 == align_address(address,
4916 stub->stub_template()->alignment()));
4917 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4921 // Write Cortex-A8 stubs.
4922 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4923 p != this->cortex_a8_stubs_.end();
4926 Cortex_a8_stub* stub = p->second;
4927 Arm_address address = this->address() + stub->offset();
4929 == align_address(address,
4930 stub->stub_template()->alignment()));
4931 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4935 // Write ARM V4BX relocation stubs.
4936 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4937 p != this->arm_v4bx_stubs_.end();
4943 Arm_address address = this->address() + (*p)->offset();
4945 == align_address(address,
4946 (*p)->stub_template()->alignment()));
4947 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4951 of->write_output_view(this->offset(), oview_size, oview);
4954 // Update the data size and address alignment of the stub table at the end
4955 // of a relaxation pass. Return true if either the data size or the
4956 // alignment changed in this relaxation pass.
4958 template<bool big_endian>
4960 Stub_table<big_endian>::update_data_size_and_addralign()
4962 // Go over all stubs in table to compute data size and address alignment.
4963 off_t size = this->reloc_stubs_size_;
4964 unsigned addralign = this->reloc_stubs_addralign_;
4966 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4967 p != this->cortex_a8_stubs_.end();
4970 const Stub_template* stub_template = p->second->stub_template();
4971 addralign = std::max(addralign, stub_template->alignment());
4972 size = (align_address(size, stub_template->alignment())
4973 + stub_template->size());
4976 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4977 p != this->arm_v4bx_stubs_.end();
4983 const Stub_template* stub_template = (*p)->stub_template();
4984 addralign = std::max(addralign, stub_template->alignment());
4985 size = (align_address(size, stub_template->alignment())
4986 + stub_template->size());
4989 // Check if either data size or alignment changed in this pass.
4990 // Update prev_data_size_ and prev_addralign_. These will be used
4991 // as the current data size and address alignment for the next pass.
4992 bool changed = size != this->prev_data_size_;
4993 this->prev_data_size_ = size;
4995 if (addralign != this->prev_addralign_)
4997 this->prev_addralign_ = addralign;
5002 // Finalize the stubs. This sets the offsets of the stubs within the stub
5003 // table. It also marks all input sections needing Cortex-A8 workaround.
5005 template<bool big_endian>
5007 Stub_table<big_endian>::finalize_stubs()
5009 off_t off = this->reloc_stubs_size_;
5010 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
5011 p != this->cortex_a8_stubs_.end();
5014 Cortex_a8_stub* stub = p->second;
5015 const Stub_template* stub_template = stub->stub_template();
5016 uint64_t stub_addralign = stub_template->alignment();
5017 off = align_address(off, stub_addralign);
5018 stub->set_offset(off);
5019 off += stub_template->size();
5021 // Mark input section so that we can determine later if a code section
5022 // needs the Cortex-A8 workaround quickly.
5023 Arm_relobj<big_endian>* arm_relobj =
5024 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
5025 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
5028 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
5029 p != this->arm_v4bx_stubs_.end();
5035 const Stub_template* stub_template = (*p)->stub_template();
5036 uint64_t stub_addralign = stub_template->alignment();
5037 off = align_address(off, stub_addralign);
5038 (*p)->set_offset(off);
5039 off += stub_template->size();
5042 gold_assert(off <= this->prev_data_size_);
5045 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
5046 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
5047 // of the address range seen by the linker.
5049 template<bool big_endian>
5051 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
5052 Target_arm<big_endian>* arm_target,
5053 unsigned char* view,
5054 Arm_address view_address,
5055 section_size_type view_size)
5057 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
5058 for (Cortex_a8_stub_list::const_iterator p =
5059 this->cortex_a8_stubs_.lower_bound(view_address);
5060 ((p != this->cortex_a8_stubs_.end())
5061 && (p->first < (view_address + view_size)));
5064 // We do not store the THUMB bit in the LSB of either the branch address
5065 // or the stub offset. There is no need to strip the LSB.
5066 Arm_address branch_address = p->first;
5067 const Cortex_a8_stub* stub = p->second;
5068 Arm_address stub_address = this->address() + stub->offset();
5070 // Offset of the branch instruction relative to this view.
5071 section_size_type offset =
5072 convert_to_section_size_type(branch_address - view_address);
5073 gold_assert((offset + 4) <= view_size);
5075 arm_target->apply_cortex_a8_workaround(stub, stub_address,
5076 view + offset, branch_address);
5080 // Arm_input_section methods.
5082 // Initialize an Arm_input_section.
5084 template<bool big_endian>
5086 Arm_input_section<big_endian>::init()
5088 Relobj* relobj = this->relobj();
5089 unsigned int shndx = this->shndx();
5091 // Cache these to speed up size and alignment queries. It is too slow
5092 // to call section_addraglin and section_size every time.
5093 this->original_addralign_ =
5094 convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
5095 this->original_size_ =
5096 convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
5098 // We want to make this look like the original input section after
5099 // output sections are finalized.
5100 Output_section* os = relobj->output_section(shndx);
5101 off_t offset = relobj->output_section_offset(shndx);
5102 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
5103 this->set_address(os->address() + offset);
5104 this->set_file_offset(os->offset() + offset);
5106 this->set_current_data_size(this->original_size_);
5107 this->finalize_data_size();
5110 template<bool big_endian>
5112 Arm_input_section<big_endian>::do_write(Output_file* of)
5114 // We have to write out the original section content.
5115 section_size_type section_size;
5116 const unsigned char* section_contents =
5117 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5118 of->write(this->offset(), section_contents, section_size);
5120 // If this owns a stub table and it is not empty, write it.
5121 if (this->is_stub_table_owner() && !this->stub_table_->empty())
5122 this->stub_table_->write(of);
5125 // Finalize data size.
5127 template<bool big_endian>
5129 Arm_input_section<big_endian>::set_final_data_size()
5131 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5133 if (this->is_stub_table_owner())
5135 this->stub_table_->finalize_data_size();
5136 off = align_address(off, this->stub_table_->addralign());
5137 off += this->stub_table_->data_size();
5139 this->set_data_size(off);
5142 // Reset address and file offset.
5144 template<bool big_endian>
5146 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
5148 // Size of the original input section contents.
5149 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
5151 // If this is a stub table owner, account for the stub table size.
5152 if (this->is_stub_table_owner())
5154 Stub_table<big_endian>* stub_table = this->stub_table_;
5156 // Reset the stub table's address and file offset. The
5157 // current data size for child will be updated after that.
5158 stub_table_->reset_address_and_file_offset();
5159 off = align_address(off, stub_table_->addralign());
5160 off += stub_table->current_data_size();
5163 this->set_current_data_size(off);
5166 // Arm_exidx_cantunwind methods.
5168 // Write this to Output file OF for a fixed endianness.
5170 template<bool big_endian>
5172 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
5174 off_t offset = this->offset();
5175 const section_size_type oview_size = 8;
5176 unsigned char* const oview = of->get_output_view(offset, oview_size);
5178 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5179 Valtype* wv = reinterpret_cast<Valtype*>(oview);
5181 Output_section* os = this->relobj_->output_section(this->shndx_);
5182 gold_assert(os != NULL);
5184 Arm_relobj<big_endian>* arm_relobj =
5185 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
5186 Arm_address output_offset =
5187 arm_relobj->get_output_section_offset(this->shndx_);
5188 Arm_address section_start;
5189 if (output_offset != Arm_relobj<big_endian>::invalid_address)
5190 section_start = os->address() + output_offset;
5193 // Currently this only happens for a relaxed section.
5194 const Output_relaxed_input_section* poris =
5195 os->find_relaxed_input_section(this->relobj_, this->shndx_);
5196 gold_assert(poris != NULL);
5197 section_start = poris->address();
5200 // We always append this to the end of an EXIDX section.
5201 Arm_address output_address =
5202 section_start + this->relobj_->section_size(this->shndx_);
5204 // Write out the entry. The first word either points to the beginning
5205 // or after the end of a text section. The second word is the special
5206 // EXIDX_CANTUNWIND value.
5207 uint32_t prel31_offset = output_address - this->address();
5208 if (utils::has_overflow<31>(offset))
5209 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
5210 elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
5211 elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
5213 of->write_output_view(this->offset(), oview_size, oview);
5216 // Arm_exidx_merged_section methods.
5218 // Constructor for Arm_exidx_merged_section.
5219 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5220 // SECTION_OFFSET_MAP points to a section offset map describing how
5221 // parts of the input section are mapped to output. DELETED_BYTES is
5222 // the number of bytes deleted from the EXIDX input section.
5224 Arm_exidx_merged_section::Arm_exidx_merged_section(
5225 const Arm_exidx_input_section& exidx_input_section,
5226 const Arm_exidx_section_offset_map& section_offset_map,
5227 uint32_t deleted_bytes)
5228 : Output_relaxed_input_section(exidx_input_section.relobj(),
5229 exidx_input_section.shndx(),
5230 exidx_input_section.addralign()),
5231 exidx_input_section_(exidx_input_section),
5232 section_offset_map_(section_offset_map)
5234 // Fix size here so that we do not need to implement set_final_data_size.
5235 this->set_data_size(exidx_input_section.size() - deleted_bytes);
5236 this->fix_data_size();
5239 // Given an input OBJECT, an input section index SHNDX within that
5240 // object, and an OFFSET relative to the start of that input
5241 // section, return whether or not the corresponding offset within
5242 // the output section is known. If this function returns true, it
5243 // sets *POUTPUT to the output offset. The value -1 indicates that
5244 // this input offset is being discarded.
5247 Arm_exidx_merged_section::do_output_offset(
5248 const Relobj* relobj,
5250 section_offset_type offset,
5251 section_offset_type* poutput) const
5253 // We only handle offsets for the original EXIDX input section.
5254 if (relobj != this->exidx_input_section_.relobj()
5255 || shndx != this->exidx_input_section_.shndx())
5258 section_offset_type section_size =
5259 convert_types<section_offset_type>(this->exidx_input_section_.size());
5260 if (offset < 0 || offset >= section_size)
5261 // Input offset is out of valid range.
5265 // We need to look up the section offset map to determine the output
5266 // offset. Find the reference point in map that is first offset
5267 // bigger than or equal to this offset.
5268 Arm_exidx_section_offset_map::const_iterator p =
5269 this->section_offset_map_.lower_bound(offset);
5271 // The section offset maps are build such that this should not happen if
5272 // input offset is in the valid range.
5273 gold_assert(p != this->section_offset_map_.end());
5275 // We need to check if this is dropped.
5276 section_offset_type ref = p->first;
5277 section_offset_type mapped_ref = p->second;
5279 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5280 // Offset is present in output.
5281 *poutput = mapped_ref + (offset - ref);
5283 // Offset is discarded owing to EXIDX entry merging.
5290 // Write this to output file OF.
5293 Arm_exidx_merged_section::do_write(Output_file* of)
5295 // If we retain or discard the whole EXIDX input section, we would
5297 gold_assert(this->data_size() != this->exidx_input_section_.size()
5298 && this->data_size() != 0);
5300 off_t offset = this->offset();
5301 const section_size_type oview_size = this->data_size();
5302 unsigned char* const oview = of->get_output_view(offset, oview_size);
5304 Output_section* os = this->relobj()->output_section(this->shndx());
5305 gold_assert(os != NULL);
5307 // Get contents of EXIDX input section.
5308 section_size_type section_size;
5309 const unsigned char* section_contents =
5310 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5311 gold_assert(section_size == this->exidx_input_section_.size());
5313 // Go over spans of input offsets and write only those that are not
5315 section_offset_type in_start = 0;
5316 section_offset_type out_start = 0;
5317 for(Arm_exidx_section_offset_map::const_iterator p =
5318 this->section_offset_map_.begin();
5319 p != this->section_offset_map_.end();
5322 section_offset_type in_end = p->first;
5323 gold_assert(in_end >= in_start);
5324 section_offset_type out_end = p->second;
5325 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5328 size_t out_chunk_size =
5329 convert_types<size_t>(out_end - out_start + 1);
5330 gold_assert(out_chunk_size == in_chunk_size);
5331 memcpy(oview + out_start, section_contents + in_start,
5333 out_start += out_chunk_size;
5335 in_start += in_chunk_size;
5338 gold_assert(convert_to_section_size_type(out_start) == oview_size);
5339 of->write_output_view(this->offset(), oview_size, oview);
5342 // Arm_exidx_fixup methods.
5344 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5345 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5346 // points to the end of the last seen EXIDX section.
5349 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5351 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5352 && this->last_input_section_ != NULL)
5354 Relobj* relobj = this->last_input_section_->relobj();
5355 unsigned int text_shndx = this->last_input_section_->link();
5356 Arm_exidx_cantunwind* cantunwind =
5357 new Arm_exidx_cantunwind(relobj, text_shndx);
5358 this->exidx_output_section_->add_output_section_data(cantunwind);
5359 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5363 // Process an EXIDX section entry in input. Return whether this entry
5364 // can be deleted in the output. SECOND_WORD in the second word of the
5368 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5371 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5373 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5374 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5375 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5377 else if ((second_word & 0x80000000) != 0)
5379 // Inlined unwinding data. Merge if equal to previous.
5380 delete_entry = (merge_exidx_entries_
5381 && this->last_unwind_type_ == UT_INLINED_ENTRY
5382 && this->last_inlined_entry_ == second_word);
5383 this->last_unwind_type_ = UT_INLINED_ENTRY;
5384 this->last_inlined_entry_ = second_word;
5388 // Normal table entry. In theory we could merge these too,
5389 // but duplicate entries are likely to be much less common.
5390 delete_entry = false;
5391 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5393 return delete_entry;
5396 // Update the current section offset map during EXIDX section fix-up.
5397 // If there is no map, create one. INPUT_OFFSET is the offset of a
5398 // reference point, DELETED_BYTES is the number of deleted by in the
5399 // section so far. If DELETE_ENTRY is true, the reference point and
5400 // all offsets after the previous reference point are discarded.
5403 Arm_exidx_fixup::update_offset_map(
5404 section_offset_type input_offset,
5405 section_size_type deleted_bytes,
5408 if (this->section_offset_map_ == NULL)
5409 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5410 section_offset_type output_offset;
5412 output_offset = Arm_exidx_input_section::invalid_offset;
5414 output_offset = input_offset - deleted_bytes;
5415 (*this->section_offset_map_)[input_offset] = output_offset;
5418 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5419 // bytes deleted. If some entries are merged, also store a pointer to a newly
5420 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5421 // caller owns the map and is responsible for releasing it after use.
5423 template<bool big_endian>
5425 Arm_exidx_fixup::process_exidx_section(
5426 const Arm_exidx_input_section* exidx_input_section,
5427 Arm_exidx_section_offset_map** psection_offset_map)
5429 Relobj* relobj = exidx_input_section->relobj();
5430 unsigned shndx = exidx_input_section->shndx();
5431 section_size_type section_size;
5432 const unsigned char* section_contents =
5433 relobj->section_contents(shndx, §ion_size, false);
5435 if ((section_size % 8) != 0)
5437 // Something is wrong with this section. Better not touch it.
5438 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5439 relobj->name().c_str(), shndx);
5440 this->last_input_section_ = exidx_input_section;
5441 this->last_unwind_type_ = UT_NONE;
5445 uint32_t deleted_bytes = 0;
5446 bool prev_delete_entry = false;
5447 gold_assert(this->section_offset_map_ == NULL);
5449 for (section_size_type i = 0; i < section_size; i += 8)
5451 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5453 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5454 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5456 bool delete_entry = this->process_exidx_entry(second_word);
5458 // Entry deletion causes changes in output offsets. We use a std::map
5459 // to record these. And entry (x, y) means input offset x
5460 // is mapped to output offset y. If y is invalid_offset, then x is
5461 // dropped in the output. Because of the way std::map::lower_bound
5462 // works, we record the last offset in a region w.r.t to keeping or
5463 // dropping. If there is no entry (x0, y0) for an input offset x0,
5464 // the output offset y0 of it is determined by the output offset y1 of
5465 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5466 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5468 if (delete_entry != prev_delete_entry && i != 0)
5469 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5471 // Update total deleted bytes for this entry.
5475 prev_delete_entry = delete_entry;
5478 // If section offset map is not NULL, make an entry for the end of
5480 if (this->section_offset_map_ != NULL)
5481 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5483 *psection_offset_map = this->section_offset_map_;
5484 this->section_offset_map_ = NULL;
5485 this->last_input_section_ = exidx_input_section;
5487 // Set the first output text section so that we can link the EXIDX output
5488 // section to it. Ignore any EXIDX input section that is completely merged.
5489 if (this->first_output_text_section_ == NULL
5490 && deleted_bytes != section_size)
5492 unsigned int link = exidx_input_section->link();
5493 Output_section* os = relobj->output_section(link);
5494 gold_assert(os != NULL);
5495 this->first_output_text_section_ = os;
5498 return deleted_bytes;
5501 // Arm_output_section methods.
5503 // Create a stub group for input sections from BEGIN to END. OWNER
5504 // points to the input section to be the owner a new stub table.
5506 template<bool big_endian>
5508 Arm_output_section<big_endian>::create_stub_group(
5509 Input_section_list::const_iterator begin,
5510 Input_section_list::const_iterator end,
5511 Input_section_list::const_iterator owner,
5512 Target_arm<big_endian>* target,
5513 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
5515 // We use a different kind of relaxed section in an EXIDX section.
5516 // The static casting from Output_relaxed_input_section to
5517 // Arm_input_section is invalid in an EXIDX section. We are okay
5518 // because we should not be calling this for an EXIDX section.
5519 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5521 // Currently we convert ordinary input sections into relaxed sections only
5522 // at this point but we may want to support creating relaxed input section
5523 // very early. So we check here to see if owner is already a relaxed
5526 Arm_input_section<big_endian>* arm_input_section;
5527 if (owner->is_relaxed_input_section())
5530 Arm_input_section<big_endian>::as_arm_input_section(
5531 owner->relaxed_input_section());
5535 gold_assert(owner->is_input_section());
5536 // Create a new relaxed input section.
5538 target->new_arm_input_section(owner->relobj(), owner->shndx());
5539 new_relaxed_sections->push_back(arm_input_section);
5542 // Create a stub table.
5543 Stub_table<big_endian>* stub_table =
5544 target->new_stub_table(arm_input_section);
5546 arm_input_section->set_stub_table(stub_table);
5548 Input_section_list::const_iterator p = begin;
5549 Input_section_list::const_iterator prev_p;
5551 // Look for input sections or relaxed input sections in [begin ... end].
5554 if (p->is_input_section() || p->is_relaxed_input_section())
5556 // The stub table information for input sections live
5557 // in their objects.
5558 Arm_relobj<big_endian>* arm_relobj =
5559 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5560 arm_relobj->set_stub_table(p->shndx(), stub_table);
5564 while (prev_p != end);
5567 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5568 // of stub groups. We grow a stub group by adding input section until the
5569 // size is just below GROUP_SIZE. The last input section will be converted
5570 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5571 // input section after the stub table, effectively double the group size.
5573 // This is similar to the group_sections() function in elf32-arm.c but is
5574 // implemented differently.
5576 template<bool big_endian>
5578 Arm_output_section<big_endian>::group_sections(
5579 section_size_type group_size,
5580 bool stubs_always_after_branch,
5581 Target_arm<big_endian>* target)
5583 // We only care about sections containing code.
5584 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5587 // States for grouping.
5590 // No group is being built.
5592 // A group is being built but the stub table is not found yet.
5593 // We keep group a stub group until the size is just under GROUP_SIZE.
5594 // The last input section in the group will be used as the stub table.
5595 FINDING_STUB_SECTION,
5596 // A group is being built and we have already found a stub table.
5597 // We enter this state to grow a stub group by adding input section
5598 // after the stub table. This effectively doubles the group size.
5602 // Any newly created relaxed sections are stored here.
5603 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5605 State state = NO_GROUP;
5606 section_size_type off = 0;
5607 section_size_type group_begin_offset = 0;
5608 section_size_type group_end_offset = 0;
5609 section_size_type stub_table_end_offset = 0;
5610 Input_section_list::const_iterator group_begin =
5611 this->input_sections().end();
5612 Input_section_list::const_iterator stub_table =
5613 this->input_sections().end();
5614 Input_section_list::const_iterator group_end = this->input_sections().end();
5615 for (Input_section_list::const_iterator p = this->input_sections().begin();
5616 p != this->input_sections().end();
5619 section_size_type section_begin_offset =
5620 align_address(off, p->addralign());
5621 section_size_type section_end_offset =
5622 section_begin_offset + p->data_size();
5624 // Check to see if we should group the previously seens sections.
5630 case FINDING_STUB_SECTION:
5631 // Adding this section makes the group larger than GROUP_SIZE.
5632 if (section_end_offset - group_begin_offset >= group_size)
5634 if (stubs_always_after_branch)
5636 gold_assert(group_end != this->input_sections().end());
5637 this->create_stub_group(group_begin, group_end, group_end,
5638 target, &new_relaxed_sections);
5643 // But wait, there's more! Input sections up to
5644 // stub_group_size bytes after the stub table can be
5645 // handled by it too.
5646 state = HAS_STUB_SECTION;
5647 stub_table = group_end;
5648 stub_table_end_offset = group_end_offset;
5653 case HAS_STUB_SECTION:
5654 // Adding this section makes the post stub-section group larger
5656 if (section_end_offset - stub_table_end_offset >= group_size)
5658 gold_assert(group_end != this->input_sections().end());
5659 this->create_stub_group(group_begin, group_end, stub_table,
5660 target, &new_relaxed_sections);
5669 // If we see an input section and currently there is no group, start
5670 // a new one. Skip any empty sections.
5671 if ((p->is_input_section() || p->is_relaxed_input_section())
5672 && (p->relobj()->section_size(p->shndx()) != 0))
5674 if (state == NO_GROUP)
5676 state = FINDING_STUB_SECTION;
5678 group_begin_offset = section_begin_offset;
5681 // Keep track of the last input section seen.
5683 group_end_offset = section_end_offset;
5686 off = section_end_offset;
5689 // Create a stub group for any ungrouped sections.
5690 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5692 gold_assert(group_end != this->input_sections().end());
5693 this->create_stub_group(group_begin, group_end,
5694 (state == FINDING_STUB_SECTION
5697 target, &new_relaxed_sections);
5700 // Convert input section into relaxed input section in a batch.
5701 if (!new_relaxed_sections.empty())
5702 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5704 // Update the section offsets
5705 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5707 Arm_relobj<big_endian>* arm_relobj =
5708 Arm_relobj<big_endian>::as_arm_relobj(
5709 new_relaxed_sections[i]->relobj());
5710 unsigned int shndx = new_relaxed_sections[i]->shndx();
5711 // Tell Arm_relobj that this input section is converted.
5712 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5716 // Append non empty text sections in this to LIST in ascending
5717 // order of their position in this.
5719 template<bool big_endian>
5721 Arm_output_section<big_endian>::append_text_sections_to_list(
5722 Text_section_list* list)
5724 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5726 for (Input_section_list::const_iterator p = this->input_sections().begin();
5727 p != this->input_sections().end();
5730 // We only care about plain or relaxed input sections. We also
5731 // ignore any merged sections.
5732 if ((p->is_input_section() || p->is_relaxed_input_section())
5733 && p->data_size() != 0)
5734 list->push_back(Text_section_list::value_type(p->relobj(),
5739 template<bool big_endian>
5741 Arm_output_section<big_endian>::fix_exidx_coverage(
5743 const Text_section_list& sorted_text_sections,
5744 Symbol_table* symtab,
5745 bool merge_exidx_entries)
5747 // We should only do this for the EXIDX output section.
5748 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5750 // We don't want the relaxation loop to undo these changes, so we discard
5751 // the current saved states and take another one after the fix-up.
5752 this->discard_states();
5754 // Remove all input sections.
5755 uint64_t address = this->address();
5756 typedef std::list<Output_section::Input_section> Input_section_list;
5757 Input_section_list input_sections;
5758 this->reset_address_and_file_offset();
5759 this->get_input_sections(address, std::string(""), &input_sections);
5761 if (!this->input_sections().empty())
5762 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5764 // Go through all the known input sections and record them.
5765 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5766 typedef Unordered_map<Section_id, const Output_section::Input_section*,
5767 Section_id_hash> Text_to_exidx_map;
5768 Text_to_exidx_map text_to_exidx_map;
5769 for (Input_section_list::const_iterator p = input_sections.begin();
5770 p != input_sections.end();
5773 // This should never happen. At this point, we should only see
5774 // plain EXIDX input sections.
5775 gold_assert(!p->is_relaxed_input_section());
5776 text_to_exidx_map[Section_id(p->relobj(), p->shndx())] = &(*p);
5779 Arm_exidx_fixup exidx_fixup(this, merge_exidx_entries);
5781 // Go over the sorted text sections.
5782 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5783 Section_id_set processed_input_sections;
5784 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5785 p != sorted_text_sections.end();
5788 Relobj* relobj = p->first;
5789 unsigned int shndx = p->second;
5791 Arm_relobj<big_endian>* arm_relobj =
5792 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5793 const Arm_exidx_input_section* exidx_input_section =
5794 arm_relobj->exidx_input_section_by_link(shndx);
5796 // If this text section has no EXIDX section or if the EXIDX section
5797 // has errors, force an EXIDX_CANTUNWIND entry pointing to the end
5798 // of the last seen EXIDX section.
5799 if (exidx_input_section == NULL || exidx_input_section->has_errors())
5801 exidx_fixup.add_exidx_cantunwind_as_needed();
5805 Relobj* exidx_relobj = exidx_input_section->relobj();
5806 unsigned int exidx_shndx = exidx_input_section->shndx();
5807 Section_id sid(exidx_relobj, exidx_shndx);
5808 Text_to_exidx_map::const_iterator iter = text_to_exidx_map.find(sid);
5809 if (iter == text_to_exidx_map.end())
5811 // This is odd. We have not seen this EXIDX input section before.
5812 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5813 // issue a warning instead. We assume the user knows what he
5814 // or she is doing. Otherwise, this is an error.
5815 if (layout->script_options()->saw_sections_clause())
5816 gold_warning(_("unwinding may not work because EXIDX input section"
5817 " %u of %s is not in EXIDX output section"),
5818 exidx_shndx, exidx_relobj->name().c_str());
5820 gold_error(_("unwinding may not work because EXIDX input section"
5821 " %u of %s is not in EXIDX output section"),
5822 exidx_shndx, exidx_relobj->name().c_str());
5824 exidx_fixup.add_exidx_cantunwind_as_needed();
5828 // Fix up coverage and append input section to output data list.
5829 Arm_exidx_section_offset_map* section_offset_map = NULL;
5830 uint32_t deleted_bytes =
5831 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5832 §ion_offset_map);
5834 if (deleted_bytes == exidx_input_section->size())
5836 // The whole EXIDX section got merged. Remove it from output.
5837 gold_assert(section_offset_map == NULL);
5838 exidx_relobj->set_output_section(exidx_shndx, NULL);
5840 // All local symbols defined in this input section will be dropped.
5841 // We need to adjust output local symbol count.
5842 arm_relobj->set_output_local_symbol_count_needs_update();
5844 else if (deleted_bytes > 0)
5846 // Some entries are merged. We need to convert this EXIDX input
5847 // section into a relaxed section.
5848 gold_assert(section_offset_map != NULL);
5849 Arm_exidx_merged_section* merged_section =
5850 new Arm_exidx_merged_section(*exidx_input_section,
5851 *section_offset_map, deleted_bytes);
5852 this->add_relaxed_input_section(merged_section);
5853 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5855 // All local symbols defined in discarded portions of this input
5856 // section will be dropped. We need to adjust output local symbol
5858 arm_relobj->set_output_local_symbol_count_needs_update();
5862 // Just add back the EXIDX input section.
5863 gold_assert(section_offset_map == NULL);
5864 const Output_section::Input_section* pis = iter->second;
5865 gold_assert(pis->is_input_section());
5866 this->add_script_input_section(*pis);
5869 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5872 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5873 exidx_fixup.add_exidx_cantunwind_as_needed();
5875 // Remove any known EXIDX input sections that are not processed.
5876 for (Input_section_list::const_iterator p = input_sections.begin();
5877 p != input_sections.end();
5880 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5881 == processed_input_sections.end())
5883 // We discard a known EXIDX section because its linked
5884 // text section has been folded by ICF. We also discard an
5885 // EXIDX section with error, the output does not matter in this
5886 // case. We do this to avoid triggering asserts.
5887 Arm_relobj<big_endian>* arm_relobj =
5888 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5889 const Arm_exidx_input_section* exidx_input_section =
5890 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5891 gold_assert(exidx_input_section != NULL);
5892 if (!exidx_input_section->has_errors())
5894 unsigned int text_shndx = exidx_input_section->link();
5895 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5898 // Remove this from link. We also need to recount the
5900 p->relobj()->set_output_section(p->shndx(), NULL);
5901 arm_relobj->set_output_local_symbol_count_needs_update();
5905 // Link exidx output section to the first seen output section and
5906 // set correct entry size.
5907 this->set_link_section(exidx_fixup.first_output_text_section());
5908 this->set_entsize(8);
5910 // Make changes permanent.
5911 this->save_states();
5912 this->set_section_offsets_need_adjustment();
5915 // Link EXIDX output sections to text output sections.
5917 template<bool big_endian>
5919 Arm_output_section<big_endian>::set_exidx_section_link()
5921 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5922 if (!this->input_sections().empty())
5924 Input_section_list::const_iterator p = this->input_sections().begin();
5925 Arm_relobj<big_endian>* arm_relobj =
5926 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5927 unsigned exidx_shndx = p->shndx();
5928 const Arm_exidx_input_section* exidx_input_section =
5929 arm_relobj->exidx_input_section_by_shndx(exidx_shndx);
5930 gold_assert(exidx_input_section != NULL);
5931 unsigned int text_shndx = exidx_input_section->link();
5932 Output_section* os = arm_relobj->output_section(text_shndx);
5933 this->set_link_section(os);
5937 // Arm_relobj methods.
5939 // Determine if an input section is scannable for stub processing. SHDR is
5940 // the header of the section and SHNDX is the section index. OS is the output
5941 // section for the input section and SYMTAB is the global symbol table used to
5942 // look up ICF information.
5944 template<bool big_endian>
5946 Arm_relobj<big_endian>::section_is_scannable(
5947 const elfcpp::Shdr<32, big_endian>& shdr,
5949 const Output_section* os,
5950 const Symbol_table* symtab)
5952 // Skip any empty sections, unallocated sections or sections whose
5953 // type are not SHT_PROGBITS.
5954 if (shdr.get_sh_size() == 0
5955 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
5956 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
5959 // Skip any discarded or ICF'ed sections.
5960 if (os == NULL || symtab->is_section_folded(this, shndx))
5963 // If this requires special offset handling, check to see if it is
5964 // a relaxed section. If this is not, then it is a merged section that
5965 // we cannot handle.
5966 if (this->is_output_section_offset_invalid(shndx))
5968 const Output_relaxed_input_section* poris =
5969 os->find_relaxed_input_section(this, shndx);
5977 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5978 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5980 template<bool big_endian>
5982 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
5983 const elfcpp::Shdr<32, big_endian>& shdr,
5984 const Relobj::Output_sections& out_sections,
5985 const Symbol_table* symtab,
5986 const unsigned char* pshdrs)
5988 unsigned int sh_type = shdr.get_sh_type();
5989 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
5992 // Ignore empty section.
5993 off_t sh_size = shdr.get_sh_size();
5997 // Ignore reloc section with unexpected symbol table. The
5998 // error will be reported in the final link.
5999 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
6002 unsigned int reloc_size;
6003 if (sh_type == elfcpp::SHT_REL)
6004 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6006 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6008 // Ignore reloc section with unexpected entsize or uneven size.
6009 // The error will be reported in the final link.
6010 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
6013 // Ignore reloc section with bad info. This error will be
6014 // reported in the final link.
6015 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
6016 if (index >= this->shnum())
6019 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6020 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
6021 return this->section_is_scannable(text_shdr, index,
6022 out_sections[index], symtab);
6025 // Return the output address of either a plain input section or a relaxed
6026 // input section. SHNDX is the section index. We define and use this
6027 // instead of calling Output_section::output_address because that is slow
6028 // for large output.
6030 template<bool big_endian>
6032 Arm_relobj<big_endian>::simple_input_section_output_address(
6036 if (this->is_output_section_offset_invalid(shndx))
6038 const Output_relaxed_input_section* poris =
6039 os->find_relaxed_input_section(this, shndx);
6040 // We do not handle merged sections here.
6041 gold_assert(poris != NULL);
6042 return poris->address();
6045 return os->address() + this->get_output_section_offset(shndx);
6048 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
6049 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
6051 template<bool big_endian>
6053 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
6054 const elfcpp::Shdr<32, big_endian>& shdr,
6057 const Symbol_table* symtab)
6059 if (!this->section_is_scannable(shdr, shndx, os, symtab))
6062 // If the section does not cross any 4K-boundaries, it does not need to
6064 Arm_address address = this->simple_input_section_output_address(shndx, os);
6065 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
6071 // Scan a section for Cortex-A8 workaround.
6073 template<bool big_endian>
6075 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
6076 const elfcpp::Shdr<32, big_endian>& shdr,
6079 Target_arm<big_endian>* arm_target)
6081 // Look for the first mapping symbol in this section. It should be
6083 Mapping_symbol_position section_start(shndx, 0);
6084 typename Mapping_symbols_info::const_iterator p =
6085 this->mapping_symbols_info_.lower_bound(section_start);
6087 // There are no mapping symbols for this section. Treat it as a data-only
6088 // section. Issue a warning if section is marked as containing
6090 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
6092 if ((this->section_flags(shndx) & elfcpp::SHF_EXECINSTR) != 0)
6093 gold_warning(_("cannot scan executable section %u of %s for Cortex-A8 "
6094 "erratum because it has no mapping symbols."),
6095 shndx, this->name().c_str());
6099 Arm_address output_address =
6100 this->simple_input_section_output_address(shndx, os);
6102 // Get the section contents.
6103 section_size_type input_view_size = 0;
6104 const unsigned char* input_view =
6105 this->section_contents(shndx, &input_view_size, false);
6107 // We need to go through the mapping symbols to determine what to
6108 // scan. There are two reasons. First, we should look at THUMB code and
6109 // THUMB code only. Second, we only want to look at the 4K-page boundary
6110 // to speed up the scanning.
6112 while (p != this->mapping_symbols_info_.end()
6113 && p->first.first == shndx)
6115 typename Mapping_symbols_info::const_iterator next =
6116 this->mapping_symbols_info_.upper_bound(p->first);
6118 // Only scan part of a section with THUMB code.
6119 if (p->second == 't')
6121 // Determine the end of this range.
6122 section_size_type span_start =
6123 convert_to_section_size_type(p->first.second);
6124 section_size_type span_end;
6125 if (next != this->mapping_symbols_info_.end()
6126 && next->first.first == shndx)
6127 span_end = convert_to_section_size_type(next->first.second);
6129 span_end = convert_to_section_size_type(shdr.get_sh_size());
6131 if (((span_start + output_address) & ~0xfffUL)
6132 != ((span_end + output_address - 1) & ~0xfffUL))
6134 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
6135 span_start, span_end,
6145 // Scan relocations for stub generation.
6147 template<bool big_endian>
6149 Arm_relobj<big_endian>::scan_sections_for_stubs(
6150 Target_arm<big_endian>* arm_target,
6151 const Symbol_table* symtab,
6152 const Layout* layout)
6154 unsigned int shnum = this->shnum();
6155 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6157 // Read the section headers.
6158 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6162 // To speed up processing, we set up hash tables for fast lookup of
6163 // input offsets to output addresses.
6164 this->initialize_input_to_output_maps();
6166 const Relobj::Output_sections& out_sections(this->output_sections());
6168 Relocate_info<32, big_endian> relinfo;
6169 relinfo.symtab = symtab;
6170 relinfo.layout = layout;
6171 relinfo.object = this;
6173 // Do relocation stubs scanning.
6174 const unsigned char* p = pshdrs + shdr_size;
6175 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6177 const elfcpp::Shdr<32, big_endian> shdr(p);
6178 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
6181 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
6182 Arm_address output_offset = this->get_output_section_offset(index);
6183 Arm_address output_address;
6184 if (output_offset != invalid_address)
6185 output_address = out_sections[index]->address() + output_offset;
6188 // Currently this only happens for a relaxed section.
6189 const Output_relaxed_input_section* poris =
6190 out_sections[index]->find_relaxed_input_section(this, index);
6191 gold_assert(poris != NULL);
6192 output_address = poris->address();
6195 // Get the relocations.
6196 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
6200 // Get the section contents. This does work for the case in which
6201 // we modify the contents of an input section. We need to pass the
6202 // output view under such circumstances.
6203 section_size_type input_view_size = 0;
6204 const unsigned char* input_view =
6205 this->section_contents(index, &input_view_size, false);
6207 relinfo.reloc_shndx = i;
6208 relinfo.data_shndx = index;
6209 unsigned int sh_type = shdr.get_sh_type();
6210 unsigned int reloc_size;
6211 if (sh_type == elfcpp::SHT_REL)
6212 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6214 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6216 Output_section* os = out_sections[index];
6217 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
6218 shdr.get_sh_size() / reloc_size,
6220 output_offset == invalid_address,
6221 input_view, output_address,
6226 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
6227 // after its relocation section, if there is one, is processed for
6228 // relocation stubs. Merging this loop with the one above would have been
6229 // complicated since we would have had to make sure that relocation stub
6230 // scanning is done first.
6231 if (arm_target->fix_cortex_a8())
6233 const unsigned char* p = pshdrs + shdr_size;
6234 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
6236 const elfcpp::Shdr<32, big_endian> shdr(p);
6237 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
6240 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
6245 // After we've done the relocations, we release the hash tables,
6246 // since we no longer need them.
6247 this->free_input_to_output_maps();
6250 // Count the local symbols. The ARM backend needs to know if a symbol
6251 // is a THUMB function or not. For global symbols, it is easy because
6252 // the Symbol object keeps the ELF symbol type. For local symbol it is
6253 // harder because we cannot access this information. So we override the
6254 // do_count_local_symbol in parent and scan local symbols to mark
6255 // THUMB functions. This is not the most efficient way but I do not want to
6256 // slow down other ports by calling a per symbol targer hook inside
6257 // Sized_relobj<size, big_endian>::do_count_local_symbols.
6259 template<bool big_endian>
6261 Arm_relobj<big_endian>::do_count_local_symbols(
6262 Stringpool_template<char>* pool,
6263 Stringpool_template<char>* dynpool)
6265 // We need to fix-up the values of any local symbols whose type are
6268 // Ask parent to count the local symbols.
6269 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
6270 const unsigned int loccount = this->local_symbol_count();
6274 // Intialize the thumb function bit-vector.
6275 std::vector<bool> empty_vector(loccount, false);
6276 this->local_symbol_is_thumb_function_.swap(empty_vector);
6278 // Read the symbol table section header.
6279 const unsigned int symtab_shndx = this->symtab_shndx();
6280 elfcpp::Shdr<32, big_endian>
6281 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6282 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6284 // Read the local symbols.
6285 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6286 gold_assert(loccount == symtabshdr.get_sh_info());
6287 off_t locsize = loccount * sym_size;
6288 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6289 locsize, true, true);
6291 // For mapping symbol processing, we need to read the symbol names.
6292 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6293 if (strtab_shndx >= this->shnum())
6295 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6299 elfcpp::Shdr<32, big_endian>
6300 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6301 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6303 this->error(_("symbol table name section has wrong type: %u"),
6304 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6307 const char* pnames =
6308 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6309 strtabshdr.get_sh_size(),
6312 // Loop over the local symbols and mark any local symbols pointing
6313 // to THUMB functions.
6315 // Skip the first dummy symbol.
6317 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
6318 this->local_values();
6319 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6321 elfcpp::Sym<32, big_endian> sym(psyms);
6322 elfcpp::STT st_type = sym.get_st_type();
6323 Symbol_value<32>& lv((*plocal_values)[i]);
6324 Arm_address input_value = lv.input_value();
6326 // Check to see if this is a mapping symbol.
6327 const char* sym_name = pnames + sym.get_st_name();
6328 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6331 unsigned int input_shndx =
6332 this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
6333 gold_assert(is_ordinary);
6335 // Strip of LSB in case this is a THUMB symbol.
6336 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6337 this->mapping_symbols_info_[msp] = sym_name[1];
6340 if (st_type == elfcpp::STT_ARM_TFUNC
6341 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6343 // This is a THUMB function. Mark this and canonicalize the
6344 // symbol value by setting LSB.
6345 this->local_symbol_is_thumb_function_[i] = true;
6346 if ((input_value & 1) == 0)
6347 lv.set_input_value(input_value | 1);
6352 // Relocate sections.
6353 template<bool big_endian>
6355 Arm_relobj<big_endian>::do_relocate_sections(
6356 const Symbol_table* symtab,
6357 const Layout* layout,
6358 const unsigned char* pshdrs,
6360 typename Sized_relobj<32, big_endian>::Views* pviews)
6362 // Call parent to relocate sections.
6363 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
6366 // We do not generate stubs if doing a relocatable link.
6367 if (parameters->options().relocatable())
6370 // Relocate stub tables.
6371 unsigned int shnum = this->shnum();
6373 Target_arm<big_endian>* arm_target =
6374 Target_arm<big_endian>::default_target();
6376 Relocate_info<32, big_endian> relinfo;
6377 relinfo.symtab = symtab;
6378 relinfo.layout = layout;
6379 relinfo.object = this;
6381 for (unsigned int i = 1; i < shnum; ++i)
6383 Arm_input_section<big_endian>* arm_input_section =
6384 arm_target->find_arm_input_section(this, i);
6386 if (arm_input_section != NULL
6387 && arm_input_section->is_stub_table_owner()
6388 && !arm_input_section->stub_table()->empty())
6390 // We cannot discard a section if it owns a stub table.
6391 Output_section* os = this->output_section(i);
6392 gold_assert(os != NULL);
6394 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6395 relinfo.reloc_shdr = NULL;
6396 relinfo.data_shndx = i;
6397 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6399 gold_assert((*pviews)[i].view != NULL);
6401 // We are passed the output section view. Adjust it to cover the
6403 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6404 gold_assert((stub_table->address() >= (*pviews)[i].address)
6405 && ((stub_table->address() + stub_table->data_size())
6406 <= (*pviews)[i].address + (*pviews)[i].view_size));
6408 off_t offset = stub_table->address() - (*pviews)[i].address;
6409 unsigned char* view = (*pviews)[i].view + offset;
6410 Arm_address address = stub_table->address();
6411 section_size_type view_size = stub_table->data_size();
6413 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6417 // Apply Cortex A8 workaround if applicable.
6418 if (this->section_has_cortex_a8_workaround(i))
6420 unsigned char* view = (*pviews)[i].view;
6421 Arm_address view_address = (*pviews)[i].address;
6422 section_size_type view_size = (*pviews)[i].view_size;
6423 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6425 // Adjust view to cover section.
6426 Output_section* os = this->output_section(i);
6427 gold_assert(os != NULL);
6428 Arm_address section_address =
6429 this->simple_input_section_output_address(i, os);
6430 uint64_t section_size = this->section_size(i);
6432 gold_assert(section_address >= view_address
6433 && ((section_address + section_size)
6434 <= (view_address + view_size)));
6436 unsigned char* section_view = view + (section_address - view_address);
6438 // Apply the Cortex-A8 workaround to the output address range
6439 // corresponding to this input section.
6440 stub_table->apply_cortex_a8_workaround_to_address_range(
6449 // Find the linked text section of an EXIDX section by looking the the first
6450 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6451 // must be linked to to its associated code section via the sh_link field of
6452 // its section header. However, some tools are broken and the link is not
6453 // always set. LD just drops such an EXIDX section silently, causing the
6454 // associated code not unwindabled. Here we try a little bit harder to
6455 // discover the linked code section.
6457 // PSHDR points to the section header of a relocation section of an EXIDX
6458 // section. If we can find a linked text section, return true and
6459 // store the text section index in the location PSHNDX. Otherwise
6462 template<bool big_endian>
6464 Arm_relobj<big_endian>::find_linked_text_section(
6465 const unsigned char* pshdr,
6466 const unsigned char* psyms,
6467 unsigned int* pshndx)
6469 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6471 // If there is no relocation, we cannot find the linked text section.
6473 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6474 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6476 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6477 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6479 // Get the relocations.
6480 const unsigned char* prelocs =
6481 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6483 // Find the REL31 relocation for the first word of the first EXIDX entry.
6484 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6486 Arm_address r_offset;
6487 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6488 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6490 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6491 r_info = reloc.get_r_info();
6492 r_offset = reloc.get_r_offset();
6496 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6497 r_info = reloc.get_r_info();
6498 r_offset = reloc.get_r_offset();
6501 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6502 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6505 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6507 || r_sym >= this->local_symbol_count()
6511 // This is the relocation for the first word of the first EXIDX entry.
6512 // We expect to see a local section symbol.
6513 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6514 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6515 if (sym.get_st_type() == elfcpp::STT_SECTION)
6519 this->adjust_sym_shndx(r_sym, sym.get_st_shndx(), &is_ordinary);
6520 gold_assert(is_ordinary);
6530 // Make an EXIDX input section object for an EXIDX section whose index is
6531 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6532 // is the section index of the linked text section.
6534 template<bool big_endian>
6536 Arm_relobj<big_endian>::make_exidx_input_section(
6538 const elfcpp::Shdr<32, big_endian>& shdr,
6539 unsigned int text_shndx,
6540 const elfcpp::Shdr<32, big_endian>& text_shdr)
6542 // Create an Arm_exidx_input_section object for this EXIDX section.
6543 Arm_exidx_input_section* exidx_input_section =
6544 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6545 shdr.get_sh_addralign());
6547 gold_assert(this->exidx_section_map_[shndx] == NULL);
6548 this->exidx_section_map_[shndx] = exidx_input_section;
6550 if (text_shndx == elfcpp::SHN_UNDEF || text_shndx >= this->shnum())
6552 gold_error(_("EXIDX section %s(%u) links to invalid section %u in %s"),
6553 this->section_name(shndx).c_str(), shndx, text_shndx,
6554 this->name().c_str());
6555 exidx_input_section->set_has_errors();
6557 else if (this->exidx_section_map_[text_shndx] != NULL)
6559 unsigned other_exidx_shndx =
6560 this->exidx_section_map_[text_shndx]->shndx();
6561 gold_error(_("EXIDX sections %s(%u) and %s(%u) both link to text section"
6563 this->section_name(shndx).c_str(), shndx,
6564 this->section_name(other_exidx_shndx).c_str(),
6565 other_exidx_shndx, this->section_name(text_shndx).c_str(),
6566 text_shndx, this->name().c_str());
6567 exidx_input_section->set_has_errors();
6570 this->exidx_section_map_[text_shndx] = exidx_input_section;
6572 // Check section flags of text section.
6573 if ((text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
6575 gold_error(_("EXIDX section %s(%u) links to non-allocated section %s(%u) "
6577 this->section_name(shndx).c_str(), shndx,
6578 this->section_name(text_shndx).c_str(), text_shndx,
6579 this->name().c_str());
6580 exidx_input_section->set_has_errors();
6582 else if ((text_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) == 0)
6583 // I would like to make this an error but currenlty ld just ignores
6585 gold_warning(_("EXIDX section %s(%u) links to non-executable section "
6587 this->section_name(shndx).c_str(), shndx,
6588 this->section_name(text_shndx).c_str(), text_shndx,
6589 this->name().c_str());
6592 // Read the symbol information.
6594 template<bool big_endian>
6596 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6598 // Call parent class to read symbol information.
6599 Sized_relobj<32, big_endian>::do_read_symbols(sd);
6601 // If this input file is a binary file, it has no processor
6602 // specific flags and attributes section.
6603 Input_file::Format format = this->input_file()->format();
6604 if (format != Input_file::FORMAT_ELF)
6606 gold_assert(format == Input_file::FORMAT_BINARY);
6607 this->merge_flags_and_attributes_ = false;
6611 // Read processor-specific flags in ELF file header.
6612 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6613 elfcpp::Elf_sizes<32>::ehdr_size,
6615 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6616 this->processor_specific_flags_ = ehdr.get_e_flags();
6618 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6620 std::vector<unsigned int> deferred_exidx_sections;
6621 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6622 const unsigned char* pshdrs = sd->section_headers->data();
6623 const unsigned char* ps = pshdrs + shdr_size;
6624 bool must_merge_flags_and_attributes = false;
6625 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6627 elfcpp::Shdr<32, big_endian> shdr(ps);
6629 // Sometimes an object has no contents except the section name string
6630 // table and an empty symbol table with the undefined symbol. We
6631 // don't want to merge processor-specific flags from such an object.
6632 if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
6634 // Symbol table is not empty.
6635 const elfcpp::Elf_types<32>::Elf_WXword sym_size =
6636 elfcpp::Elf_sizes<32>::sym_size;
6637 if (shdr.get_sh_size() > sym_size)
6638 must_merge_flags_and_attributes = true;
6640 else if (shdr.get_sh_type() != elfcpp::SHT_STRTAB)
6641 // If this is neither an empty symbol table nor a string table,
6643 must_merge_flags_and_attributes = true;
6645 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6647 gold_assert(this->attributes_section_data_ == NULL);
6648 section_offset_type section_offset = shdr.get_sh_offset();
6649 section_size_type section_size =
6650 convert_to_section_size_type(shdr.get_sh_size());
6651 File_view* view = this->get_lasting_view(section_offset,
6652 section_size, true, false);
6653 this->attributes_section_data_ =
6654 new Attributes_section_data(view->data(), section_size);
6656 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6658 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6659 if (text_shndx == elfcpp::SHN_UNDEF)
6660 deferred_exidx_sections.push_back(i);
6663 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6664 + text_shndx * shdr_size);
6665 this->make_exidx_input_section(i, shdr, text_shndx, text_shdr);
6671 if (!must_merge_flags_and_attributes)
6673 gold_assert(deferred_exidx_sections.empty());
6674 this->merge_flags_and_attributes_ = false;
6678 // Some tools are broken and they do not set the link of EXIDX sections.
6679 // We look at the first relocation to figure out the linked sections.
6680 if (!deferred_exidx_sections.empty())
6682 // We need to go over the section headers again to find the mapping
6683 // from sections being relocated to their relocation sections. This is
6684 // a bit inefficient as we could do that in the loop above. However,
6685 // we do not expect any deferred EXIDX sections normally. So we do not
6686 // want to slow down the most common path.
6687 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6688 Reloc_map reloc_map;
6689 ps = pshdrs + shdr_size;
6690 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6692 elfcpp::Shdr<32, big_endian> shdr(ps);
6693 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6694 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6696 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6697 if (info_shndx >= this->shnum())
6698 gold_error(_("relocation section %u has invalid info %u"),
6700 Reloc_map::value_type value(info_shndx, i);
6701 std::pair<Reloc_map::iterator, bool> result =
6702 reloc_map.insert(value);
6704 gold_error(_("section %u has multiple relocation sections "
6706 info_shndx, i, reloc_map[info_shndx]);
6710 // Read the symbol table section header.
6711 const unsigned int symtab_shndx = this->symtab_shndx();
6712 elfcpp::Shdr<32, big_endian>
6713 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6714 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6716 // Read the local symbols.
6717 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6718 const unsigned int loccount = this->local_symbol_count();
6719 gold_assert(loccount == symtabshdr.get_sh_info());
6720 off_t locsize = loccount * sym_size;
6721 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6722 locsize, true, true);
6724 // Process the deferred EXIDX sections.
6725 for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6727 unsigned int shndx = deferred_exidx_sections[i];
6728 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6729 unsigned int text_shndx = elfcpp::SHN_UNDEF;
6730 Reloc_map::const_iterator it = reloc_map.find(shndx);
6731 if (it != reloc_map.end())
6732 find_linked_text_section(pshdrs + it->second * shdr_size,
6733 psyms, &text_shndx);
6734 elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
6735 + text_shndx * shdr_size);
6736 this->make_exidx_input_section(shndx, shdr, text_shndx, text_shdr);
6741 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6742 // sections for unwinding. These sections are referenced implicitly by
6743 // text sections linked in the section headers. If we ignore these implict
6744 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6745 // will be garbage-collected incorrectly. Hence we override the same function
6746 // in the base class to handle these implicit references.
6748 template<bool big_endian>
6750 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6752 Read_relocs_data* rd)
6754 // First, call base class method to process relocations in this object.
6755 Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6757 // If --gc-sections is not specified, there is nothing more to do.
6758 // This happens when --icf is used but --gc-sections is not.
6759 if (!parameters->options().gc_sections())
6762 unsigned int shnum = this->shnum();
6763 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6764 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6768 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6769 // to these from the linked text sections.
6770 const unsigned char* ps = pshdrs + shdr_size;
6771 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6773 elfcpp::Shdr<32, big_endian> shdr(ps);
6774 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6776 // Found an .ARM.exidx section, add it to the set of reachable
6777 // sections from its linked text section.
6778 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6779 symtab->gc()->add_reference(this, text_shndx, this, i);
6784 // Update output local symbol count. Owing to EXIDX entry merging, some local
6785 // symbols will be removed in output. Adjust output local symbol count
6786 // accordingly. We can only changed the static output local symbol count. It
6787 // is too late to change the dynamic symbols.
6789 template<bool big_endian>
6791 Arm_relobj<big_endian>::update_output_local_symbol_count()
6793 // Caller should check that this needs updating. We want caller checking
6794 // because output_local_symbol_count_needs_update() is most likely inlined.
6795 gold_assert(this->output_local_symbol_count_needs_update_);
6797 gold_assert(this->symtab_shndx() != -1U);
6798 if (this->symtab_shndx() == 0)
6800 // This object has no symbols. Weird but legal.
6804 // Read the symbol table section header.
6805 const unsigned int symtab_shndx = this->symtab_shndx();
6806 elfcpp::Shdr<32, big_endian>
6807 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6808 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6810 // Read the local symbols.
6811 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6812 const unsigned int loccount = this->local_symbol_count();
6813 gold_assert(loccount == symtabshdr.get_sh_info());
6814 off_t locsize = loccount * sym_size;
6815 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6816 locsize, true, true);
6818 // Loop over the local symbols.
6820 typedef typename Sized_relobj<32, big_endian>::Output_sections
6822 const Output_sections& out_sections(this->output_sections());
6823 unsigned int shnum = this->shnum();
6824 unsigned int count = 0;
6825 // Skip the first, dummy, symbol.
6827 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6829 elfcpp::Sym<32, big_endian> sym(psyms);
6831 Symbol_value<32>& lv((*this->local_values())[i]);
6833 // This local symbol was already discarded by do_count_local_symbols.
6834 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6838 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6843 Output_section* os = out_sections[shndx];
6845 // This local symbol no longer has an output section. Discard it.
6848 lv.set_no_output_symtab_entry();
6852 // Currently we only discard parts of EXIDX input sections.
6853 // We explicitly check for a merged EXIDX input section to avoid
6854 // calling Output_section_data::output_offset unless necessary.
6855 if ((this->get_output_section_offset(shndx) == invalid_address)
6856 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6858 section_offset_type output_offset =
6859 os->output_offset(this, shndx, lv.input_value());
6860 if (output_offset == -1)
6862 // This symbol is defined in a part of an EXIDX input section
6863 // that is discarded due to entry merging.
6864 lv.set_no_output_symtab_entry();
6873 this->set_output_local_symbol_count(count);
6874 this->output_local_symbol_count_needs_update_ = false;
6877 // Arm_dynobj methods.
6879 // Read the symbol information.
6881 template<bool big_endian>
6883 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6885 // Call parent class to read symbol information.
6886 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6888 // Read processor-specific flags in ELF file header.
6889 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6890 elfcpp::Elf_sizes<32>::ehdr_size,
6892 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6893 this->processor_specific_flags_ = ehdr.get_e_flags();
6895 // Read the attributes section if there is one.
6896 // We read from the end because gas seems to put it near the end of
6897 // the section headers.
6898 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6899 const unsigned char* ps =
6900 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6901 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6903 elfcpp::Shdr<32, big_endian> shdr(ps);
6904 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6906 section_offset_type section_offset = shdr.get_sh_offset();
6907 section_size_type section_size =
6908 convert_to_section_size_type(shdr.get_sh_size());
6909 File_view* view = this->get_lasting_view(section_offset,
6910 section_size, true, false);
6911 this->attributes_section_data_ =
6912 new Attributes_section_data(view->data(), section_size);
6918 // Stub_addend_reader methods.
6920 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6922 template<bool big_endian>
6923 elfcpp::Elf_types<32>::Elf_Swxword
6924 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
6925 unsigned int r_type,
6926 const unsigned char* view,
6927 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
6929 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
6933 case elfcpp::R_ARM_CALL:
6934 case elfcpp::R_ARM_JUMP24:
6935 case elfcpp::R_ARM_PLT32:
6937 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6938 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6939 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
6940 return utils::sign_extend<26>(val << 2);
6943 case elfcpp::R_ARM_THM_CALL:
6944 case elfcpp::R_ARM_THM_JUMP24:
6945 case elfcpp::R_ARM_THM_XPC22:
6947 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6948 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6949 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6950 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6951 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
6954 case elfcpp::R_ARM_THM_JUMP19:
6956 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6957 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6958 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6959 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6960 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
6968 // Arm_output_data_got methods.
6970 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
6971 // The first one is initialized to be 1, which is the module index for
6972 // the main executable and the second one 0. A reloc of the type
6973 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
6974 // be applied by gold. GSYM is a global symbol.
6976 template<bool big_endian>
6978 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6979 unsigned int got_type,
6982 if (gsym->has_got_offset(got_type))
6985 // We are doing a static link. Just mark it as belong to module 1,
6987 unsigned int got_offset = this->add_constant(1);
6988 gsym->set_got_offset(got_type, got_offset);
6989 got_offset = this->add_constant(0);
6990 this->static_relocs_.push_back(Static_reloc(got_offset,
6991 elfcpp::R_ARM_TLS_DTPOFF32,
6995 // Same as the above but for a local symbol.
6997 template<bool big_endian>
6999 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
7000 unsigned int got_type,
7001 Sized_relobj<32, big_endian>* object,
7004 if (object->local_has_got_offset(index, got_type))
7007 // We are doing a static link. Just mark it as belong to module 1,
7009 unsigned int got_offset = this->add_constant(1);
7010 object->set_local_got_offset(index, got_type, got_offset);
7011 got_offset = this->add_constant(0);
7012 this->static_relocs_.push_back(Static_reloc(got_offset,
7013 elfcpp::R_ARM_TLS_DTPOFF32,
7017 template<bool big_endian>
7019 Arm_output_data_got<big_endian>::do_write(Output_file* of)
7021 // Call parent to write out GOT.
7022 Output_data_got<32, big_endian>::do_write(of);
7024 // We are done if there is no fix up.
7025 if (this->static_relocs_.empty())
7028 gold_assert(parameters->doing_static_link());
7030 const off_t offset = this->offset();
7031 const section_size_type oview_size =
7032 convert_to_section_size_type(this->data_size());
7033 unsigned char* const oview = of->get_output_view(offset, oview_size);
7035 Output_segment* tls_segment = this->layout_->tls_segment();
7036 gold_assert(tls_segment != NULL);
7038 // The thread pointer $tp points to the TCB, which is followed by the
7039 // TLS. So we need to adjust $tp relative addressing by this amount.
7040 Arm_address aligned_tcb_size =
7041 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
7043 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
7045 Static_reloc& reloc(this->static_relocs_[i]);
7048 if (!reloc.symbol_is_global())
7050 Sized_relobj<32, big_endian>* object = reloc.relobj();
7051 const Symbol_value<32>* psymval =
7052 reloc.relobj()->local_symbol(reloc.index());
7054 // We are doing static linking. Issue an error and skip this
7055 // relocation if the symbol is undefined or in a discarded_section.
7057 unsigned int shndx = psymval->input_shndx(&is_ordinary);
7058 if ((shndx == elfcpp::SHN_UNDEF)
7060 && shndx != elfcpp::SHN_UNDEF
7061 && !object->is_section_included(shndx)
7062 && !this->symbol_table_->is_section_folded(object, shndx)))
7064 gold_error(_("undefined or discarded local symbol %u from "
7065 " object %s in GOT"),
7066 reloc.index(), reloc.relobj()->name().c_str());
7070 value = psymval->value(object, 0);
7074 const Symbol* gsym = reloc.symbol();
7075 gold_assert(gsym != NULL);
7076 if (gsym->is_forwarder())
7077 gsym = this->symbol_table_->resolve_forwards(gsym);
7079 // We are doing static linking. Issue an error and skip this
7080 // relocation if the symbol is undefined or in a discarded_section
7081 // unless it is a weakly_undefined symbol.
7082 if ((gsym->is_defined_in_discarded_section()
7083 || gsym->is_undefined())
7084 && !gsym->is_weak_undefined())
7086 gold_error(_("undefined or discarded symbol %s in GOT"),
7091 if (!gsym->is_weak_undefined())
7093 const Sized_symbol<32>* sym =
7094 static_cast<const Sized_symbol<32>*>(gsym);
7095 value = sym->value();
7101 unsigned got_offset = reloc.got_offset();
7102 gold_assert(got_offset < oview_size);
7104 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
7105 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
7107 switch (reloc.r_type())
7109 case elfcpp::R_ARM_TLS_DTPOFF32:
7112 case elfcpp::R_ARM_TLS_TPOFF32:
7113 x = value + aligned_tcb_size;
7118 elfcpp::Swap<32, big_endian>::writeval(wv, x);
7121 of->write_output_view(offset, oview_size, oview);
7124 // A class to handle the PLT data.
7126 template<bool big_endian>
7127 class Output_data_plt_arm : public Output_section_data
7130 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
7133 Output_data_plt_arm(Layout*, Output_data_space*);
7135 // Add an entry to the PLT.
7137 add_entry(Symbol* gsym);
7139 // Return the .rel.plt section data.
7140 const Reloc_section*
7142 { return this->rel_; }
7144 // Return the number of PLT entries.
7147 { return this->count_; }
7149 // Return the offset of the first non-reserved PLT entry.
7151 first_plt_entry_offset()
7152 { return sizeof(first_plt_entry); }
7154 // Return the size of a PLT entry.
7156 get_plt_entry_size()
7157 { return sizeof(plt_entry); }
7161 do_adjust_output_section(Output_section* os);
7163 // Write to a map file.
7165 do_print_to_mapfile(Mapfile* mapfile) const
7166 { mapfile->print_output_data(this, _("** PLT")); }
7169 // Template for the first PLT entry.
7170 static const uint32_t first_plt_entry[5];
7172 // Template for subsequent PLT entries.
7173 static const uint32_t plt_entry[3];
7175 // Set the final size.
7177 set_final_data_size()
7179 this->set_data_size(sizeof(first_plt_entry)
7180 + this->count_ * sizeof(plt_entry));
7183 // Write out the PLT data.
7185 do_write(Output_file*);
7187 // The reloc section.
7188 Reloc_section* rel_;
7189 // The .got.plt section.
7190 Output_data_space* got_plt_;
7191 // The number of PLT entries.
7192 unsigned int count_;
7195 // Create the PLT section. The ordinary .got section is an argument,
7196 // since we need to refer to the start. We also create our own .got
7197 // section just for PLT entries.
7199 template<bool big_endian>
7200 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
7201 Output_data_space* got_plt)
7202 : Output_section_data(4), got_plt_(got_plt), count_(0)
7204 this->rel_ = new Reloc_section(false);
7205 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
7206 elfcpp::SHF_ALLOC, this->rel_,
7207 ORDER_DYNAMIC_PLT_RELOCS, false);
7210 template<bool big_endian>
7212 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
7217 // Add an entry to the PLT.
7219 template<bool big_endian>
7221 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
7223 gold_assert(!gsym->has_plt_offset());
7225 // Note that when setting the PLT offset we skip the initial
7226 // reserved PLT entry.
7227 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
7228 + sizeof(first_plt_entry));
7232 section_offset_type got_offset = this->got_plt_->current_data_size();
7234 // Every PLT entry needs a GOT entry which points back to the PLT
7235 // entry (this will be changed by the dynamic linker, normally
7236 // lazily when the function is called).
7237 this->got_plt_->set_current_data_size(got_offset + 4);
7239 // Every PLT entry needs a reloc.
7240 gsym->set_needs_dynsym_entry();
7241 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
7244 // Note that we don't need to save the symbol. The contents of the
7245 // PLT are independent of which symbols are used. The symbols only
7246 // appear in the relocations.
7250 // FIXME: This is not very flexible. Right now this has only been tested
7251 // on armv5te. If we are to support additional architecture features like
7252 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
7254 // The first entry in the PLT.
7255 template<bool big_endian>
7256 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
7258 0xe52de004, // str lr, [sp, #-4]!
7259 0xe59fe004, // ldr lr, [pc, #4]
7260 0xe08fe00e, // add lr, pc, lr
7261 0xe5bef008, // ldr pc, [lr, #8]!
7262 0x00000000, // &GOT[0] - .
7265 // Subsequent entries in the PLT.
7267 template<bool big_endian>
7268 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
7270 0xe28fc600, // add ip, pc, #0xNN00000
7271 0xe28cca00, // add ip, ip, #0xNN000
7272 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
7275 // Write out the PLT. This uses the hand-coded instructions above,
7276 // and adjusts them as needed. This is all specified by the arm ELF
7277 // Processor Supplement.
7279 template<bool big_endian>
7281 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
7283 const off_t offset = this->offset();
7284 const section_size_type oview_size =
7285 convert_to_section_size_type(this->data_size());
7286 unsigned char* const oview = of->get_output_view(offset, oview_size);
7288 const off_t got_file_offset = this->got_plt_->offset();
7289 const section_size_type got_size =
7290 convert_to_section_size_type(this->got_plt_->data_size());
7291 unsigned char* const got_view = of->get_output_view(got_file_offset,
7293 unsigned char* pov = oview;
7295 Arm_address plt_address = this->address();
7296 Arm_address got_address = this->got_plt_->address();
7298 // Write first PLT entry. All but the last word are constants.
7299 const size_t num_first_plt_words = (sizeof(first_plt_entry)
7300 / sizeof(plt_entry[0]));
7301 for (size_t i = 0; i < num_first_plt_words - 1; i++)
7302 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
7303 // Last word in first PLT entry is &GOT[0] - .
7304 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
7305 got_address - (plt_address + 16));
7306 pov += sizeof(first_plt_entry);
7308 unsigned char* got_pov = got_view;
7310 memset(got_pov, 0, 12);
7313 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
7314 unsigned int plt_offset = sizeof(first_plt_entry);
7315 unsigned int plt_rel_offset = 0;
7316 unsigned int got_offset = 12;
7317 const unsigned int count = this->count_;
7318 for (unsigned int i = 0;
7321 pov += sizeof(plt_entry),
7323 plt_offset += sizeof(plt_entry),
7324 plt_rel_offset += rel_size,
7327 // Set and adjust the PLT entry itself.
7328 int32_t offset = ((got_address + got_offset)
7329 - (plt_address + plt_offset + 8));
7331 gold_assert(offset >= 0 && offset < 0x0fffffff);
7332 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
7333 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
7334 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
7335 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
7336 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
7337 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7339 // Set the entry in the GOT.
7340 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7343 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7344 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7346 of->write_output_view(offset, oview_size, oview);
7347 of->write_output_view(got_file_offset, got_size, got_view);
7350 // Create a PLT entry for a global symbol.
7352 template<bool big_endian>
7354 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7357 if (gsym->has_plt_offset())
7360 if (this->plt_ == NULL)
7362 // Create the GOT sections first.
7363 this->got_section(symtab, layout);
7365 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
7366 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7368 | elfcpp::SHF_EXECINSTR),
7369 this->plt_, ORDER_PLT, false);
7371 this->plt_->add_entry(gsym);
7374 // Return the number of entries in the PLT.
7376 template<bool big_endian>
7378 Target_arm<big_endian>::plt_entry_count() const
7380 if (this->plt_ == NULL)
7382 return this->plt_->entry_count();
7385 // Return the offset of the first non-reserved PLT entry.
7387 template<bool big_endian>
7389 Target_arm<big_endian>::first_plt_entry_offset() const
7391 return Output_data_plt_arm<big_endian>::first_plt_entry_offset();
7394 // Return the size of each PLT entry.
7396 template<bool big_endian>
7398 Target_arm<big_endian>::plt_entry_size() const
7400 return Output_data_plt_arm<big_endian>::get_plt_entry_size();
7403 // Get the section to use for TLS_DESC relocations.
7405 template<bool big_endian>
7406 typename Target_arm<big_endian>::Reloc_section*
7407 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7409 return this->plt_section()->rel_tls_desc(layout);
7412 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7414 template<bool big_endian>
7416 Target_arm<big_endian>::define_tls_base_symbol(
7417 Symbol_table* symtab,
7420 if (this->tls_base_symbol_defined_)
7423 Output_segment* tls_segment = layout->tls_segment();
7424 if (tls_segment != NULL)
7426 bool is_exec = parameters->options().output_is_executable();
7427 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7428 Symbol_table::PREDEFINED,
7432 elfcpp::STV_HIDDEN, 0,
7434 ? Symbol::SEGMENT_END
7435 : Symbol::SEGMENT_START),
7438 this->tls_base_symbol_defined_ = true;
7441 // Create a GOT entry for the TLS module index.
7443 template<bool big_endian>
7445 Target_arm<big_endian>::got_mod_index_entry(
7446 Symbol_table* symtab,
7448 Sized_relobj<32, big_endian>* object)
7450 if (this->got_mod_index_offset_ == -1U)
7452 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7453 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7454 unsigned int got_offset;
7455 if (!parameters->doing_static_link())
7457 got_offset = got->add_constant(0);
7458 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7459 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7464 // We are doing a static link. Just mark it as belong to module 1,
7466 got_offset = got->add_constant(1);
7469 got->add_constant(0);
7470 this->got_mod_index_offset_ = got_offset;
7472 return this->got_mod_index_offset_;
7475 // Optimize the TLS relocation type based on what we know about the
7476 // symbol. IS_FINAL is true if the final address of this symbol is
7477 // known at link time.
7479 template<bool big_endian>
7480 tls::Tls_optimization
7481 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7483 // FIXME: Currently we do not do any TLS optimization.
7484 return tls::TLSOPT_NONE;
7487 // Report an unsupported relocation against a local symbol.
7489 template<bool big_endian>
7491 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7492 Sized_relobj<32, big_endian>* object,
7493 unsigned int r_type)
7495 gold_error(_("%s: unsupported reloc %u against local symbol"),
7496 object->name().c_str(), r_type);
7499 // We are about to emit a dynamic relocation of type R_TYPE. If the
7500 // dynamic linker does not support it, issue an error. The GNU linker
7501 // only issues a non-PIC error for an allocated read-only section.
7502 // Here we know the section is allocated, but we don't know that it is
7503 // read-only. But we check for all the relocation types which the
7504 // glibc dynamic linker supports, so it seems appropriate to issue an
7505 // error even if the section is not read-only.
7507 template<bool big_endian>
7509 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7510 unsigned int r_type)
7514 // These are the relocation types supported by glibc for ARM.
7515 case elfcpp::R_ARM_RELATIVE:
7516 case elfcpp::R_ARM_COPY:
7517 case elfcpp::R_ARM_GLOB_DAT:
7518 case elfcpp::R_ARM_JUMP_SLOT:
7519 case elfcpp::R_ARM_ABS32:
7520 case elfcpp::R_ARM_ABS32_NOI:
7521 case elfcpp::R_ARM_PC24:
7522 // FIXME: The following 3 types are not supported by Android's dynamic
7524 case elfcpp::R_ARM_TLS_DTPMOD32:
7525 case elfcpp::R_ARM_TLS_DTPOFF32:
7526 case elfcpp::R_ARM_TLS_TPOFF32:
7531 // This prevents us from issuing more than one error per reloc
7532 // section. But we can still wind up issuing more than one
7533 // error per object file.
7534 if (this->issued_non_pic_error_)
7536 const Arm_reloc_property* reloc_property =
7537 arm_reloc_property_table->get_reloc_property(r_type);
7538 gold_assert(reloc_property != NULL);
7539 object->error(_("requires unsupported dynamic reloc %s; "
7540 "recompile with -fPIC"),
7541 reloc_property->name().c_str());
7542 this->issued_non_pic_error_ = true;
7546 case elfcpp::R_ARM_NONE:
7551 // Scan a relocation for a local symbol.
7552 // FIXME: This only handles a subset of relocation types used by Android
7553 // on ARM v5te devices.
7555 template<bool big_endian>
7557 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7560 Sized_relobj<32, big_endian>* object,
7561 unsigned int data_shndx,
7562 Output_section* output_section,
7563 const elfcpp::Rel<32, big_endian>& reloc,
7564 unsigned int r_type,
7565 const elfcpp::Sym<32, big_endian>& lsym)
7567 r_type = get_real_reloc_type(r_type);
7570 case elfcpp::R_ARM_NONE:
7571 case elfcpp::R_ARM_V4BX:
7572 case elfcpp::R_ARM_GNU_VTENTRY:
7573 case elfcpp::R_ARM_GNU_VTINHERIT:
7576 case elfcpp::R_ARM_ABS32:
7577 case elfcpp::R_ARM_ABS32_NOI:
7578 // If building a shared library (or a position-independent
7579 // executable), we need to create a dynamic relocation for
7580 // this location. The relocation applied at link time will
7581 // apply the link-time value, so we flag the location with
7582 // an R_ARM_RELATIVE relocation so the dynamic loader can
7583 // relocate it easily.
7584 if (parameters->options().output_is_position_independent())
7586 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7587 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7588 // If we are to add more other reloc types than R_ARM_ABS32,
7589 // we need to add check_non_pic(object, r_type) here.
7590 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7591 output_section, data_shndx,
7592 reloc.get_r_offset());
7596 case elfcpp::R_ARM_ABS16:
7597 case elfcpp::R_ARM_ABS12:
7598 case elfcpp::R_ARM_THM_ABS5:
7599 case elfcpp::R_ARM_ABS8:
7600 case elfcpp::R_ARM_BASE_ABS:
7601 case elfcpp::R_ARM_MOVW_ABS_NC:
7602 case elfcpp::R_ARM_MOVT_ABS:
7603 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7604 case elfcpp::R_ARM_THM_MOVT_ABS:
7605 // If building a shared library (or a position-independent
7606 // executable), we need to create a dynamic relocation for
7607 // this location. Because the addend needs to remain in the
7608 // data section, we need to be careful not to apply this
7609 // relocation statically.
7610 if (parameters->options().output_is_position_independent())
7612 check_non_pic(object, r_type);
7613 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7614 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7615 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7616 rel_dyn->add_local(object, r_sym, r_type, output_section,
7617 data_shndx, reloc.get_r_offset());
7620 gold_assert(lsym.get_st_value() == 0);
7621 unsigned int shndx = lsym.get_st_shndx();
7623 shndx = object->adjust_sym_shndx(r_sym, shndx,
7626 object->error(_("section symbol %u has bad shndx %u"),
7629 rel_dyn->add_local_section(object, shndx,
7630 r_type, output_section,
7631 data_shndx, reloc.get_r_offset());
7636 case elfcpp::R_ARM_REL32:
7637 case elfcpp::R_ARM_LDR_PC_G0:
7638 case elfcpp::R_ARM_SBREL32:
7639 case elfcpp::R_ARM_THM_CALL:
7640 case elfcpp::R_ARM_THM_PC8:
7641 case elfcpp::R_ARM_BASE_PREL:
7642 case elfcpp::R_ARM_PLT32:
7643 case elfcpp::R_ARM_CALL:
7644 case elfcpp::R_ARM_JUMP24:
7645 case elfcpp::R_ARM_THM_JUMP24:
7646 case elfcpp::R_ARM_SBREL31:
7647 case elfcpp::R_ARM_PREL31:
7648 case elfcpp::R_ARM_MOVW_PREL_NC:
7649 case elfcpp::R_ARM_MOVT_PREL:
7650 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7651 case elfcpp::R_ARM_THM_MOVT_PREL:
7652 case elfcpp::R_ARM_THM_JUMP19:
7653 case elfcpp::R_ARM_THM_JUMP6:
7654 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7655 case elfcpp::R_ARM_THM_PC12:
7656 case elfcpp::R_ARM_REL32_NOI:
7657 case elfcpp::R_ARM_ALU_PC_G0_NC:
7658 case elfcpp::R_ARM_ALU_PC_G0:
7659 case elfcpp::R_ARM_ALU_PC_G1_NC:
7660 case elfcpp::R_ARM_ALU_PC_G1:
7661 case elfcpp::R_ARM_ALU_PC_G2:
7662 case elfcpp::R_ARM_LDR_PC_G1:
7663 case elfcpp::R_ARM_LDR_PC_G2:
7664 case elfcpp::R_ARM_LDRS_PC_G0:
7665 case elfcpp::R_ARM_LDRS_PC_G1:
7666 case elfcpp::R_ARM_LDRS_PC_G2:
7667 case elfcpp::R_ARM_LDC_PC_G0:
7668 case elfcpp::R_ARM_LDC_PC_G1:
7669 case elfcpp::R_ARM_LDC_PC_G2:
7670 case elfcpp::R_ARM_ALU_SB_G0_NC:
7671 case elfcpp::R_ARM_ALU_SB_G0:
7672 case elfcpp::R_ARM_ALU_SB_G1_NC:
7673 case elfcpp::R_ARM_ALU_SB_G1:
7674 case elfcpp::R_ARM_ALU_SB_G2:
7675 case elfcpp::R_ARM_LDR_SB_G0:
7676 case elfcpp::R_ARM_LDR_SB_G1:
7677 case elfcpp::R_ARM_LDR_SB_G2:
7678 case elfcpp::R_ARM_LDRS_SB_G0:
7679 case elfcpp::R_ARM_LDRS_SB_G1:
7680 case elfcpp::R_ARM_LDRS_SB_G2:
7681 case elfcpp::R_ARM_LDC_SB_G0:
7682 case elfcpp::R_ARM_LDC_SB_G1:
7683 case elfcpp::R_ARM_LDC_SB_G2:
7684 case elfcpp::R_ARM_MOVW_BREL_NC:
7685 case elfcpp::R_ARM_MOVT_BREL:
7686 case elfcpp::R_ARM_MOVW_BREL:
7687 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7688 case elfcpp::R_ARM_THM_MOVT_BREL:
7689 case elfcpp::R_ARM_THM_MOVW_BREL:
7690 case elfcpp::R_ARM_THM_JUMP11:
7691 case elfcpp::R_ARM_THM_JUMP8:
7692 // We don't need to do anything for a relative addressing relocation
7693 // against a local symbol if it does not reference the GOT.
7696 case elfcpp::R_ARM_GOTOFF32:
7697 case elfcpp::R_ARM_GOTOFF12:
7698 // We need a GOT section:
7699 target->got_section(symtab, layout);
7702 case elfcpp::R_ARM_GOT_BREL:
7703 case elfcpp::R_ARM_GOT_PREL:
7705 // The symbol requires a GOT entry.
7706 Arm_output_data_got<big_endian>* got =
7707 target->got_section(symtab, layout);
7708 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7709 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
7711 // If we are generating a shared object, we need to add a
7712 // dynamic RELATIVE relocation for this symbol's GOT entry.
7713 if (parameters->options().output_is_position_independent())
7715 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7716 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7717 rel_dyn->add_local_relative(
7718 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
7719 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
7725 case elfcpp::R_ARM_TARGET1:
7726 case elfcpp::R_ARM_TARGET2:
7727 // This should have been mapped to another type already.
7729 case elfcpp::R_ARM_COPY:
7730 case elfcpp::R_ARM_GLOB_DAT:
7731 case elfcpp::R_ARM_JUMP_SLOT:
7732 case elfcpp::R_ARM_RELATIVE:
7733 // These are relocations which should only be seen by the
7734 // dynamic linker, and should never be seen here.
7735 gold_error(_("%s: unexpected reloc %u in object file"),
7736 object->name().c_str(), r_type);
7740 // These are initial TLS relocs, which are expected when
7742 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7743 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7744 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7745 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7746 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7748 bool output_is_shared = parameters->options().shared();
7749 const tls::Tls_optimization optimized_type
7750 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
7754 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7755 if (optimized_type == tls::TLSOPT_NONE)
7757 // Create a pair of GOT entries for the module index and
7758 // dtv-relative offset.
7759 Arm_output_data_got<big_endian>* got
7760 = target->got_section(symtab, layout);
7761 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7762 unsigned int shndx = lsym.get_st_shndx();
7764 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
7767 object->error(_("local symbol %u has bad shndx %u"),
7772 if (!parameters->doing_static_link())
7773 got->add_local_pair_with_rel(object, r_sym, shndx,
7775 target->rel_dyn_section(layout),
7776 elfcpp::R_ARM_TLS_DTPMOD32, 0);
7778 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
7782 // FIXME: TLS optimization not supported yet.
7786 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7787 if (optimized_type == tls::TLSOPT_NONE)
7789 // Create a GOT entry for the module index.
7790 target->got_mod_index_entry(symtab, layout, object);
7793 // FIXME: TLS optimization not supported yet.
7797 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7800 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7801 layout->set_has_static_tls();
7802 if (optimized_type == tls::TLSOPT_NONE)
7804 // Create a GOT entry for the tp-relative offset.
7805 Arm_output_data_got<big_endian>* got
7806 = target->got_section(symtab, layout);
7807 unsigned int r_sym =
7808 elfcpp::elf_r_sym<32>(reloc.get_r_info());
7809 if (!parameters->doing_static_link())
7810 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
7811 target->rel_dyn_section(layout),
7812 elfcpp::R_ARM_TLS_TPOFF32);
7813 else if (!object->local_has_got_offset(r_sym,
7814 GOT_TYPE_TLS_OFFSET))
7816 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
7817 unsigned int got_offset =
7818 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
7819 got->add_static_reloc(got_offset,
7820 elfcpp::R_ARM_TLS_TPOFF32, object,
7825 // FIXME: TLS optimization not supported yet.
7829 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7830 layout->set_has_static_tls();
7831 if (output_is_shared)
7833 // We need to create a dynamic relocation.
7834 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7835 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7836 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7837 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
7838 output_section, data_shndx,
7839 reloc.get_r_offset());
7849 case elfcpp::R_ARM_PC24:
7850 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7851 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7852 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7854 unsupported_reloc_local(object, r_type);
7859 // Report an unsupported relocation against a global symbol.
7861 template<bool big_endian>
7863 Target_arm<big_endian>::Scan::unsupported_reloc_global(
7864 Sized_relobj<32, big_endian>* object,
7865 unsigned int r_type,
7868 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
7869 object->name().c_str(), r_type, gsym->demangled_name().c_str());
7872 template<bool big_endian>
7874 Target_arm<big_endian>::Scan::possible_function_pointer_reloc(
7875 unsigned int r_type)
7879 case elfcpp::R_ARM_PC24:
7880 case elfcpp::R_ARM_THM_CALL:
7881 case elfcpp::R_ARM_PLT32:
7882 case elfcpp::R_ARM_CALL:
7883 case elfcpp::R_ARM_JUMP24:
7884 case elfcpp::R_ARM_THM_JUMP24:
7885 case elfcpp::R_ARM_SBREL31:
7886 case elfcpp::R_ARM_PREL31:
7887 case elfcpp::R_ARM_THM_JUMP19:
7888 case elfcpp::R_ARM_THM_JUMP6:
7889 case elfcpp::R_ARM_THM_JUMP11:
7890 case elfcpp::R_ARM_THM_JUMP8:
7891 // All the relocations above are branches except SBREL31 and PREL31.
7895 // Be conservative and assume this is a function pointer.
7900 template<bool big_endian>
7902 Target_arm<big_endian>::Scan::local_reloc_may_be_function_pointer(
7905 Target_arm<big_endian>* target,
7906 Sized_relobj<32, big_endian>*,
7909 const elfcpp::Rel<32, big_endian>&,
7910 unsigned int r_type,
7911 const elfcpp::Sym<32, big_endian>&)
7913 r_type = target->get_real_reloc_type(r_type);
7914 return possible_function_pointer_reloc(r_type);
7917 template<bool big_endian>
7919 Target_arm<big_endian>::Scan::global_reloc_may_be_function_pointer(
7922 Target_arm<big_endian>* target,
7923 Sized_relobj<32, big_endian>*,
7926 const elfcpp::Rel<32, big_endian>&,
7927 unsigned int r_type,
7930 // GOT is not a function.
7931 if (strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7934 r_type = target->get_real_reloc_type(r_type);
7935 return possible_function_pointer_reloc(r_type);
7938 // Scan a relocation for a global symbol.
7940 template<bool big_endian>
7942 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
7945 Sized_relobj<32, big_endian>* object,
7946 unsigned int data_shndx,
7947 Output_section* output_section,
7948 const elfcpp::Rel<32, big_endian>& reloc,
7949 unsigned int r_type,
7952 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
7953 // section. We check here to avoid creating a dynamic reloc against
7954 // _GLOBAL_OFFSET_TABLE_.
7955 if (!target->has_got_section()
7956 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7957 target->got_section(symtab, layout);
7959 r_type = get_real_reloc_type(r_type);
7962 case elfcpp::R_ARM_NONE:
7963 case elfcpp::R_ARM_V4BX:
7964 case elfcpp::R_ARM_GNU_VTENTRY:
7965 case elfcpp::R_ARM_GNU_VTINHERIT:
7968 case elfcpp::R_ARM_ABS32:
7969 case elfcpp::R_ARM_ABS16:
7970 case elfcpp::R_ARM_ABS12:
7971 case elfcpp::R_ARM_THM_ABS5:
7972 case elfcpp::R_ARM_ABS8:
7973 case elfcpp::R_ARM_BASE_ABS:
7974 case elfcpp::R_ARM_MOVW_ABS_NC:
7975 case elfcpp::R_ARM_MOVT_ABS:
7976 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7977 case elfcpp::R_ARM_THM_MOVT_ABS:
7978 case elfcpp::R_ARM_ABS32_NOI:
7979 // Absolute addressing relocations.
7981 // Make a PLT entry if necessary.
7982 if (this->symbol_needs_plt_entry(gsym))
7984 target->make_plt_entry(symtab, layout, gsym);
7985 // Since this is not a PC-relative relocation, we may be
7986 // taking the address of a function. In that case we need to
7987 // set the entry in the dynamic symbol table to the address of
7989 if (gsym->is_from_dynobj() && !parameters->options().shared())
7990 gsym->set_needs_dynsym_value();
7992 // Make a dynamic relocation if necessary.
7993 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
7995 if (gsym->may_need_copy_reloc())
7997 target->copy_reloc(symtab, layout, object,
7998 data_shndx, output_section, gsym, reloc);
8000 else if ((r_type == elfcpp::R_ARM_ABS32
8001 || r_type == elfcpp::R_ARM_ABS32_NOI)
8002 && gsym->can_use_relative_reloc(false))
8004 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8005 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
8006 output_section, object,
8007 data_shndx, reloc.get_r_offset());
8011 check_non_pic(object, r_type);
8012 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8013 rel_dyn->add_global(gsym, r_type, output_section, object,
8014 data_shndx, reloc.get_r_offset());
8020 case elfcpp::R_ARM_GOTOFF32:
8021 case elfcpp::R_ARM_GOTOFF12:
8022 // We need a GOT section.
8023 target->got_section(symtab, layout);
8026 case elfcpp::R_ARM_REL32:
8027 case elfcpp::R_ARM_LDR_PC_G0:
8028 case elfcpp::R_ARM_SBREL32:
8029 case elfcpp::R_ARM_THM_PC8:
8030 case elfcpp::R_ARM_BASE_PREL:
8031 case elfcpp::R_ARM_MOVW_PREL_NC:
8032 case elfcpp::R_ARM_MOVT_PREL:
8033 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8034 case elfcpp::R_ARM_THM_MOVT_PREL:
8035 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8036 case elfcpp::R_ARM_THM_PC12:
8037 case elfcpp::R_ARM_REL32_NOI:
8038 case elfcpp::R_ARM_ALU_PC_G0_NC:
8039 case elfcpp::R_ARM_ALU_PC_G0:
8040 case elfcpp::R_ARM_ALU_PC_G1_NC:
8041 case elfcpp::R_ARM_ALU_PC_G1:
8042 case elfcpp::R_ARM_ALU_PC_G2:
8043 case elfcpp::R_ARM_LDR_PC_G1:
8044 case elfcpp::R_ARM_LDR_PC_G2:
8045 case elfcpp::R_ARM_LDRS_PC_G0:
8046 case elfcpp::R_ARM_LDRS_PC_G1:
8047 case elfcpp::R_ARM_LDRS_PC_G2:
8048 case elfcpp::R_ARM_LDC_PC_G0:
8049 case elfcpp::R_ARM_LDC_PC_G1:
8050 case elfcpp::R_ARM_LDC_PC_G2:
8051 case elfcpp::R_ARM_ALU_SB_G0_NC:
8052 case elfcpp::R_ARM_ALU_SB_G0:
8053 case elfcpp::R_ARM_ALU_SB_G1_NC:
8054 case elfcpp::R_ARM_ALU_SB_G1:
8055 case elfcpp::R_ARM_ALU_SB_G2:
8056 case elfcpp::R_ARM_LDR_SB_G0:
8057 case elfcpp::R_ARM_LDR_SB_G1:
8058 case elfcpp::R_ARM_LDR_SB_G2:
8059 case elfcpp::R_ARM_LDRS_SB_G0:
8060 case elfcpp::R_ARM_LDRS_SB_G1:
8061 case elfcpp::R_ARM_LDRS_SB_G2:
8062 case elfcpp::R_ARM_LDC_SB_G0:
8063 case elfcpp::R_ARM_LDC_SB_G1:
8064 case elfcpp::R_ARM_LDC_SB_G2:
8065 case elfcpp::R_ARM_MOVW_BREL_NC:
8066 case elfcpp::R_ARM_MOVT_BREL:
8067 case elfcpp::R_ARM_MOVW_BREL:
8068 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8069 case elfcpp::R_ARM_THM_MOVT_BREL:
8070 case elfcpp::R_ARM_THM_MOVW_BREL:
8071 // Relative addressing relocations.
8073 // Make a dynamic relocation if necessary.
8074 int flags = Symbol::NON_PIC_REF;
8075 if (gsym->needs_dynamic_reloc(flags))
8077 if (target->may_need_copy_reloc(gsym))
8079 target->copy_reloc(symtab, layout, object,
8080 data_shndx, output_section, gsym, reloc);
8084 check_non_pic(object, r_type);
8085 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8086 rel_dyn->add_global(gsym, r_type, output_section, object,
8087 data_shndx, reloc.get_r_offset());
8093 case elfcpp::R_ARM_THM_CALL:
8094 case elfcpp::R_ARM_PLT32:
8095 case elfcpp::R_ARM_CALL:
8096 case elfcpp::R_ARM_JUMP24:
8097 case elfcpp::R_ARM_THM_JUMP24:
8098 case elfcpp::R_ARM_SBREL31:
8099 case elfcpp::R_ARM_PREL31:
8100 case elfcpp::R_ARM_THM_JUMP19:
8101 case elfcpp::R_ARM_THM_JUMP6:
8102 case elfcpp::R_ARM_THM_JUMP11:
8103 case elfcpp::R_ARM_THM_JUMP8:
8104 // All the relocation above are branches except for the PREL31 ones.
8105 // A PREL31 relocation can point to a personality function in a shared
8106 // library. In that case we want to use a PLT because we want to
8107 // call the personality routine and the dyanmic linkers we care about
8108 // do not support dynamic PREL31 relocations. An REL31 relocation may
8109 // point to a function whose unwinding behaviour is being described but
8110 // we will not mistakenly generate a PLT for that because we should use
8111 // a local section symbol.
8113 // If the symbol is fully resolved, this is just a relative
8114 // local reloc. Otherwise we need a PLT entry.
8115 if (gsym->final_value_is_known())
8117 // If building a shared library, we can also skip the PLT entry
8118 // if the symbol is defined in the output file and is protected
8120 if (gsym->is_defined()
8121 && !gsym->is_from_dynobj()
8122 && !gsym->is_preemptible())
8124 target->make_plt_entry(symtab, layout, gsym);
8127 case elfcpp::R_ARM_GOT_BREL:
8128 case elfcpp::R_ARM_GOT_ABS:
8129 case elfcpp::R_ARM_GOT_PREL:
8131 // The symbol requires a GOT entry.
8132 Arm_output_data_got<big_endian>* got =
8133 target->got_section(symtab, layout);
8134 if (gsym->final_value_is_known())
8135 got->add_global(gsym, GOT_TYPE_STANDARD);
8138 // If this symbol is not fully resolved, we need to add a
8139 // GOT entry with a dynamic relocation.
8140 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8141 if (gsym->is_from_dynobj()
8142 || gsym->is_undefined()
8143 || gsym->is_preemptible())
8144 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
8145 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
8148 if (got->add_global(gsym, GOT_TYPE_STANDARD))
8149 rel_dyn->add_global_relative(
8150 gsym, elfcpp::R_ARM_RELATIVE, got,
8151 gsym->got_offset(GOT_TYPE_STANDARD));
8157 case elfcpp::R_ARM_TARGET1:
8158 case elfcpp::R_ARM_TARGET2:
8159 // These should have been mapped to other types already.
8161 case elfcpp::R_ARM_COPY:
8162 case elfcpp::R_ARM_GLOB_DAT:
8163 case elfcpp::R_ARM_JUMP_SLOT:
8164 case elfcpp::R_ARM_RELATIVE:
8165 // These are relocations which should only be seen by the
8166 // dynamic linker, and should never be seen here.
8167 gold_error(_("%s: unexpected reloc %u in object file"),
8168 object->name().c_str(), r_type);
8171 // These are initial tls relocs, which are expected when
8173 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8174 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8175 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8176 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8177 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8179 const bool is_final = gsym->final_value_is_known();
8180 const tls::Tls_optimization optimized_type
8181 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8184 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8185 if (optimized_type == tls::TLSOPT_NONE)
8187 // Create a pair of GOT entries for the module index and
8188 // dtv-relative offset.
8189 Arm_output_data_got<big_endian>* got
8190 = target->got_section(symtab, layout);
8191 if (!parameters->doing_static_link())
8192 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
8193 target->rel_dyn_section(layout),
8194 elfcpp::R_ARM_TLS_DTPMOD32,
8195 elfcpp::R_ARM_TLS_DTPOFF32);
8197 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
8200 // FIXME: TLS optimization not supported yet.
8204 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8205 if (optimized_type == tls::TLSOPT_NONE)
8207 // Create a GOT entry for the module index.
8208 target->got_mod_index_entry(symtab, layout, object);
8211 // FIXME: TLS optimization not supported yet.
8215 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8218 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8219 layout->set_has_static_tls();
8220 if (optimized_type == tls::TLSOPT_NONE)
8222 // Create a GOT entry for the tp-relative offset.
8223 Arm_output_data_got<big_endian>* got
8224 = target->got_section(symtab, layout);
8225 if (!parameters->doing_static_link())
8226 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
8227 target->rel_dyn_section(layout),
8228 elfcpp::R_ARM_TLS_TPOFF32);
8229 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
8231 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
8232 unsigned int got_offset =
8233 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
8234 got->add_static_reloc(got_offset,
8235 elfcpp::R_ARM_TLS_TPOFF32, gsym);
8239 // FIXME: TLS optimization not supported yet.
8243 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8244 layout->set_has_static_tls();
8245 if (parameters->options().shared())
8247 // We need to create a dynamic relocation.
8248 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8249 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
8250 output_section, object,
8251 data_shndx, reloc.get_r_offset());
8261 case elfcpp::R_ARM_PC24:
8262 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
8263 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
8264 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
8266 unsupported_reloc_global(object, r_type, gsym);
8271 // Process relocations for gc.
8273 template<bool big_endian>
8275 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
8277 Sized_relobj<32, big_endian>* object,
8278 unsigned int data_shndx,
8280 const unsigned char* prelocs,
8282 Output_section* output_section,
8283 bool needs_special_offset_handling,
8284 size_t local_symbol_count,
8285 const unsigned char* plocal_symbols)
8287 typedef Target_arm<big_endian> Arm;
8288 typedef typename Target_arm<big_endian>::Scan Scan;
8290 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan,
8291 typename Target_arm::Relocatable_size_for_reloc>(
8300 needs_special_offset_handling,
8305 // Scan relocations for a section.
8307 template<bool big_endian>
8309 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
8311 Sized_relobj<32, big_endian>* object,
8312 unsigned int data_shndx,
8313 unsigned int sh_type,
8314 const unsigned char* prelocs,
8316 Output_section* output_section,
8317 bool needs_special_offset_handling,
8318 size_t local_symbol_count,
8319 const unsigned char* plocal_symbols)
8321 typedef typename Target_arm<big_endian>::Scan Scan;
8322 if (sh_type == elfcpp::SHT_RELA)
8324 gold_error(_("%s: unsupported RELA reloc section"),
8325 object->name().c_str());
8329 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
8338 needs_special_offset_handling,
8343 // Finalize the sections.
8345 template<bool big_endian>
8347 Target_arm<big_endian>::do_finalize_sections(
8349 const Input_objects* input_objects,
8350 Symbol_table* symtab)
8352 bool merged_any_attributes = false;
8353 // Merge processor-specific flags.
8354 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
8355 p != input_objects->relobj_end();
8358 Arm_relobj<big_endian>* arm_relobj =
8359 Arm_relobj<big_endian>::as_arm_relobj(*p);
8360 if (arm_relobj->merge_flags_and_attributes())
8362 this->merge_processor_specific_flags(
8364 arm_relobj->processor_specific_flags());
8365 this->merge_object_attributes(arm_relobj->name().c_str(),
8366 arm_relobj->attributes_section_data());
8367 merged_any_attributes = true;
8371 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
8372 p != input_objects->dynobj_end();
8375 Arm_dynobj<big_endian>* arm_dynobj =
8376 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
8377 this->merge_processor_specific_flags(
8379 arm_dynobj->processor_specific_flags());
8380 this->merge_object_attributes(arm_dynobj->name().c_str(),
8381 arm_dynobj->attributes_section_data());
8382 merged_any_attributes = true;
8385 // Create an empty uninitialized attribute section if we still don't have it
8386 // at this moment. This happens if there is no attributes sections in all
8388 if (this->attributes_section_data_ == NULL)
8389 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
8392 const Object_attribute* cpu_arch_attr =
8393 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
8394 if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
8395 this->set_may_use_blx(true);
8397 // Check if we need to use Cortex-A8 workaround.
8398 if (parameters->options().user_set_fix_cortex_a8())
8399 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
8402 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
8403 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
8405 const Object_attribute* cpu_arch_profile_attr =
8406 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
8407 this->fix_cortex_a8_ =
8408 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
8409 && (cpu_arch_profile_attr->int_value() == 'A'
8410 || cpu_arch_profile_attr->int_value() == 0));
8413 // Check if we can use V4BX interworking.
8414 // The V4BX interworking stub contains BX instruction,
8415 // which is not specified for some profiles.
8416 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
8417 && !this->may_use_blx())
8418 gold_error(_("unable to provide V4BX reloc interworking fix up; "
8419 "the target profile does not support BX instruction"));
8421 // Fill in some more dynamic tags.
8422 const Reloc_section* rel_plt = (this->plt_ == NULL
8424 : this->plt_->rel_plt());
8425 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
8426 this->rel_dyn_, true, false);
8428 // Emit any relocs we saved in an attempt to avoid generating COPY
8430 if (this->copy_relocs_.any_saved_relocs())
8431 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8433 // Handle the .ARM.exidx section.
8434 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8436 if (!parameters->options().relocatable())
8438 if (exidx_section != NULL
8439 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX)
8441 // Create __exidx_start and __exdix_end symbols.
8442 symtab->define_in_output_data("__exidx_start", NULL,
8443 Symbol_table::PREDEFINED,
8444 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8445 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN,
8447 symtab->define_in_output_data("__exidx_end", NULL,
8448 Symbol_table::PREDEFINED,
8449 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8450 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN,
8453 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8454 // the .ARM.exidx section.
8455 if (!layout->script_options()->saw_phdrs_clause())
8457 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0,
8460 Output_segment* exidx_segment =
8461 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8462 exidx_segment->add_output_section_to_nonload(exidx_section,
8468 symtab->define_as_constant("__exidx_start", NULL,
8469 Symbol_table::PREDEFINED,
8470 0, 0, elfcpp::STT_OBJECT,
8471 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8473 symtab->define_as_constant("__exidx_end", NULL,
8474 Symbol_table::PREDEFINED,
8475 0, 0, elfcpp::STT_OBJECT,
8476 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8481 // Create an .ARM.attributes section if we have merged any attributes
8483 if (merged_any_attributes)
8485 Output_attributes_section_data* attributes_section =
8486 new Output_attributes_section_data(*this->attributes_section_data_);
8487 layout->add_output_section_data(".ARM.attributes",
8488 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8489 attributes_section, ORDER_INVALID,
8493 // Fix up links in section EXIDX headers.
8494 for (Layout::Section_list::const_iterator p = layout->section_list().begin();
8495 p != layout->section_list().end();
8497 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
8499 Arm_output_section<big_endian>* os =
8500 Arm_output_section<big_endian>::as_arm_output_section(*p);
8501 os->set_exidx_section_link();
8505 // Return whether a direct absolute static relocation needs to be applied.
8506 // In cases where Scan::local() or Scan::global() has created
8507 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8508 // of the relocation is carried in the data, and we must not
8509 // apply the static relocation.
8511 template<bool big_endian>
8513 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8514 const Sized_symbol<32>* gsym,
8517 Output_section* output_section)
8519 // If the output section is not allocated, then we didn't call
8520 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8522 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8525 // For local symbols, we will have created a non-RELATIVE dynamic
8526 // relocation only if (a) the output is position independent,
8527 // (b) the relocation is absolute (not pc- or segment-relative), and
8528 // (c) the relocation is not 32 bits wide.
8530 return !(parameters->options().output_is_position_independent()
8531 && (ref_flags & Symbol::ABSOLUTE_REF)
8534 // For global symbols, we use the same helper routines used in the
8535 // scan pass. If we did not create a dynamic relocation, or if we
8536 // created a RELATIVE dynamic relocation, we should apply the static
8538 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8539 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8540 && gsym->can_use_relative_reloc(ref_flags
8541 & Symbol::FUNCTION_CALL);
8542 return !has_dyn || is_rel;
8545 // Perform a relocation.
8547 template<bool big_endian>
8549 Target_arm<big_endian>::Relocate::relocate(
8550 const Relocate_info<32, big_endian>* relinfo,
8552 Output_section* output_section,
8554 const elfcpp::Rel<32, big_endian>& rel,
8555 unsigned int r_type,
8556 const Sized_symbol<32>* gsym,
8557 const Symbol_value<32>* psymval,
8558 unsigned char* view,
8559 Arm_address address,
8560 section_size_type view_size)
8562 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8564 r_type = get_real_reloc_type(r_type);
8565 const Arm_reloc_property* reloc_property =
8566 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8567 if (reloc_property == NULL)
8569 std::string reloc_name =
8570 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8571 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8572 _("cannot relocate %s in object file"),
8573 reloc_name.c_str());
8577 const Arm_relobj<big_endian>* object =
8578 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8580 // If the final branch target of a relocation is THUMB instruction, this
8581 // is 1. Otherwise it is 0.
8582 Arm_address thumb_bit = 0;
8583 Symbol_value<32> symval;
8584 bool is_weakly_undefined_without_plt = false;
8585 bool have_got_offset = false;
8586 unsigned int got_offset = 0;
8588 // If the relocation uses the GOT entry of a symbol instead of the symbol
8589 // itself, we don't care about whether the symbol is defined or what kind
8591 if (reloc_property->uses_got_entry())
8593 // Get the GOT offset.
8594 // The GOT pointer points to the end of the GOT section.
8595 // We need to subtract the size of the GOT section to get
8596 // the actual offset to use in the relocation.
8597 // TODO: We should move GOT offset computing code in TLS relocations
8601 case elfcpp::R_ARM_GOT_BREL:
8602 case elfcpp::R_ARM_GOT_PREL:
8605 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8606 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8607 - target->got_size());
8611 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8612 gold_assert(object->local_has_got_offset(r_sym,
8613 GOT_TYPE_STANDARD));
8614 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8615 - target->got_size());
8617 have_got_offset = true;
8624 else if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8628 // This is a global symbol. Determine if we use PLT and if the
8629 // final target is THUMB.
8630 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
8632 // This uses a PLT, change the symbol value.
8633 symval.set_output_value(target->plt_section()->address()
8634 + gsym->plt_offset());
8637 else if (gsym->is_weak_undefined())
8639 // This is a weakly undefined symbol and we do not use PLT
8640 // for this relocation. A branch targeting this symbol will
8641 // be converted into an NOP.
8642 is_weakly_undefined_without_plt = true;
8644 else if (gsym->is_undefined() && reloc_property->uses_symbol())
8646 // This relocation uses the symbol value but the symbol is
8647 // undefined. Exit early and have the caller reporting an
8653 // Set thumb bit if symbol:
8654 // -Has type STT_ARM_TFUNC or
8655 // -Has type STT_FUNC, is defined and with LSB in value set.
8657 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8658 || (gsym->type() == elfcpp::STT_FUNC
8659 && !gsym->is_undefined()
8660 && ((psymval->value(object, 0) & 1) != 0)))
8667 // This is a local symbol. Determine if the final target is THUMB.
8668 // We saved this information when all the local symbols were read.
8669 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8670 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8671 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8676 // This is a fake relocation synthesized for a stub. It does not have
8677 // a real symbol. We just look at the LSB of the symbol value to
8678 // determine if the target is THUMB or not.
8679 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8682 // Strip LSB if this points to a THUMB target.
8684 && reloc_property->uses_thumb_bit()
8685 && ((psymval->value(object, 0) & 1) != 0))
8687 Arm_address stripped_value =
8688 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8689 symval.set_output_value(stripped_value);
8693 // To look up relocation stubs, we need to pass the symbol table index of
8695 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8697 // Get the addressing origin of the output segment defining the
8698 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8699 Arm_address sym_origin = 0;
8700 if (reloc_property->uses_symbol_base())
8702 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8703 // R_ARM_BASE_ABS with the NULL symbol will give the
8704 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8705 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8706 sym_origin = target->got_plt_section()->address();
8707 else if (gsym == NULL)
8709 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8710 sym_origin = gsym->output_segment()->vaddr();
8711 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8712 sym_origin = gsym->output_data()->address();
8714 // TODO: Assumes the segment base to be zero for the global symbols
8715 // till the proper support for the segment-base-relative addressing
8716 // will be implemented. This is consistent with GNU ld.
8719 // For relative addressing relocation, find out the relative address base.
8720 Arm_address relative_address_base = 0;
8721 switch(reloc_property->relative_address_base())
8723 case Arm_reloc_property::RAB_NONE:
8724 // Relocations with relative address bases RAB_TLS and RAB_tp are
8725 // handled by relocate_tls. So we do not need to do anything here.
8726 case Arm_reloc_property::RAB_TLS:
8727 case Arm_reloc_property::RAB_tp:
8729 case Arm_reloc_property::RAB_B_S:
8730 relative_address_base = sym_origin;
8732 case Arm_reloc_property::RAB_GOT_ORG:
8733 relative_address_base = target->got_plt_section()->address();
8735 case Arm_reloc_property::RAB_P:
8736 relative_address_base = address;
8738 case Arm_reloc_property::RAB_Pa:
8739 relative_address_base = address & 0xfffffffcU;
8745 typename Arm_relocate_functions::Status reloc_status =
8746 Arm_relocate_functions::STATUS_OKAY;
8747 bool check_overflow = reloc_property->checks_overflow();
8750 case elfcpp::R_ARM_NONE:
8753 case elfcpp::R_ARM_ABS8:
8754 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8756 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
8759 case elfcpp::R_ARM_ABS12:
8760 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8762 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
8765 case elfcpp::R_ARM_ABS16:
8766 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8768 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
8771 case elfcpp::R_ARM_ABS32:
8772 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8774 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8778 case elfcpp::R_ARM_ABS32_NOI:
8779 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8781 // No thumb bit for this relocation: (S + A)
8782 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8786 case elfcpp::R_ARM_MOVW_ABS_NC:
8787 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8789 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
8794 case elfcpp::R_ARM_MOVT_ABS:
8795 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8797 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
8800 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8801 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8803 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
8804 0, thumb_bit, false);
8807 case elfcpp::R_ARM_THM_MOVT_ABS:
8808 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8810 reloc_status = Arm_relocate_functions::thm_movt(view, object,
8814 case elfcpp::R_ARM_MOVW_PREL_NC:
8815 case elfcpp::R_ARM_MOVW_BREL_NC:
8816 case elfcpp::R_ARM_MOVW_BREL:
8818 Arm_relocate_functions::movw(view, object, psymval,
8819 relative_address_base, thumb_bit,
8823 case elfcpp::R_ARM_MOVT_PREL:
8824 case elfcpp::R_ARM_MOVT_BREL:
8826 Arm_relocate_functions::movt(view, object, psymval,
8827 relative_address_base);
8830 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8831 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8832 case elfcpp::R_ARM_THM_MOVW_BREL:
8834 Arm_relocate_functions::thm_movw(view, object, psymval,
8835 relative_address_base,
8836 thumb_bit, check_overflow);
8839 case elfcpp::R_ARM_THM_MOVT_PREL:
8840 case elfcpp::R_ARM_THM_MOVT_BREL:
8842 Arm_relocate_functions::thm_movt(view, object, psymval,
8843 relative_address_base);
8846 case elfcpp::R_ARM_REL32:
8847 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8848 address, thumb_bit);
8851 case elfcpp::R_ARM_THM_ABS5:
8852 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8854 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
8857 // Thumb long branches.
8858 case elfcpp::R_ARM_THM_CALL:
8859 case elfcpp::R_ARM_THM_XPC22:
8860 case elfcpp::R_ARM_THM_JUMP24:
8862 Arm_relocate_functions::thumb_branch_common(
8863 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8864 thumb_bit, is_weakly_undefined_without_plt);
8867 case elfcpp::R_ARM_GOTOFF32:
8869 Arm_address got_origin;
8870 got_origin = target->got_plt_section()->address();
8871 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8872 got_origin, thumb_bit);
8876 case elfcpp::R_ARM_BASE_PREL:
8877 gold_assert(gsym != NULL);
8879 Arm_relocate_functions::base_prel(view, sym_origin, address);
8882 case elfcpp::R_ARM_BASE_ABS:
8884 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8888 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
8892 case elfcpp::R_ARM_GOT_BREL:
8893 gold_assert(have_got_offset);
8894 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
8897 case elfcpp::R_ARM_GOT_PREL:
8898 gold_assert(have_got_offset);
8899 // Get the address origin for GOT PLT, which is allocated right
8900 // after the GOT section, to calculate an absolute address of
8901 // the symbol GOT entry (got_origin + got_offset).
8902 Arm_address got_origin;
8903 got_origin = target->got_plt_section()->address();
8904 reloc_status = Arm_relocate_functions::got_prel(view,
8905 got_origin + got_offset,
8909 case elfcpp::R_ARM_PLT32:
8910 case elfcpp::R_ARM_CALL:
8911 case elfcpp::R_ARM_JUMP24:
8912 case elfcpp::R_ARM_XPC25:
8913 gold_assert(gsym == NULL
8914 || gsym->has_plt_offset()
8915 || gsym->final_value_is_known()
8916 || (gsym->is_defined()
8917 && !gsym->is_from_dynobj()
8918 && !gsym->is_preemptible()));
8920 Arm_relocate_functions::arm_branch_common(
8921 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8922 thumb_bit, is_weakly_undefined_without_plt);
8925 case elfcpp::R_ARM_THM_JUMP19:
8927 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
8931 case elfcpp::R_ARM_THM_JUMP6:
8933 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
8936 case elfcpp::R_ARM_THM_JUMP8:
8938 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
8941 case elfcpp::R_ARM_THM_JUMP11:
8943 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
8946 case elfcpp::R_ARM_PREL31:
8947 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
8948 address, thumb_bit);
8951 case elfcpp::R_ARM_V4BX:
8952 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
8954 const bool is_v4bx_interworking =
8955 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
8957 Arm_relocate_functions::v4bx(relinfo, view, object, address,
8958 is_v4bx_interworking);
8962 case elfcpp::R_ARM_THM_PC8:
8964 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
8967 case elfcpp::R_ARM_THM_PC12:
8969 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
8972 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8974 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
8978 case elfcpp::R_ARM_ALU_PC_G0_NC:
8979 case elfcpp::R_ARM_ALU_PC_G0:
8980 case elfcpp::R_ARM_ALU_PC_G1_NC:
8981 case elfcpp::R_ARM_ALU_PC_G1:
8982 case elfcpp::R_ARM_ALU_PC_G2:
8983 case elfcpp::R_ARM_ALU_SB_G0_NC:
8984 case elfcpp::R_ARM_ALU_SB_G0:
8985 case elfcpp::R_ARM_ALU_SB_G1_NC:
8986 case elfcpp::R_ARM_ALU_SB_G1:
8987 case elfcpp::R_ARM_ALU_SB_G2:
8989 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
8990 reloc_property->group_index(),
8991 relative_address_base,
8992 thumb_bit, check_overflow);
8995 case elfcpp::R_ARM_LDR_PC_G0:
8996 case elfcpp::R_ARM_LDR_PC_G1:
8997 case elfcpp::R_ARM_LDR_PC_G2:
8998 case elfcpp::R_ARM_LDR_SB_G0:
8999 case elfcpp::R_ARM_LDR_SB_G1:
9000 case elfcpp::R_ARM_LDR_SB_G2:
9002 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
9003 reloc_property->group_index(),
9004 relative_address_base);
9007 case elfcpp::R_ARM_LDRS_PC_G0:
9008 case elfcpp::R_ARM_LDRS_PC_G1:
9009 case elfcpp::R_ARM_LDRS_PC_G2:
9010 case elfcpp::R_ARM_LDRS_SB_G0:
9011 case elfcpp::R_ARM_LDRS_SB_G1:
9012 case elfcpp::R_ARM_LDRS_SB_G2:
9014 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
9015 reloc_property->group_index(),
9016 relative_address_base);
9019 case elfcpp::R_ARM_LDC_PC_G0:
9020 case elfcpp::R_ARM_LDC_PC_G1:
9021 case elfcpp::R_ARM_LDC_PC_G2:
9022 case elfcpp::R_ARM_LDC_SB_G0:
9023 case elfcpp::R_ARM_LDC_SB_G1:
9024 case elfcpp::R_ARM_LDC_SB_G2:
9026 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
9027 reloc_property->group_index(),
9028 relative_address_base);
9031 // These are initial tls relocs, which are expected when
9033 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
9034 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
9035 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
9036 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
9037 case elfcpp::R_ARM_TLS_LE32: // Local-exec
9039 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
9040 view, address, view_size);
9043 // The known and unknown unsupported and/or deprecated relocations.
9044 case elfcpp::R_ARM_PC24:
9045 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
9046 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
9047 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
9049 // Just silently leave the method. We should get an appropriate error
9050 // message in the scan methods.
9054 // Report any errors.
9055 switch (reloc_status)
9057 case Arm_relocate_functions::STATUS_OKAY:
9059 case Arm_relocate_functions::STATUS_OVERFLOW:
9060 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
9061 _("relocation overflow in %s"),
9062 reloc_property->name().c_str());
9064 case Arm_relocate_functions::STATUS_BAD_RELOC:
9065 gold_error_at_location(
9069 _("unexpected opcode while processing relocation %s"),
9070 reloc_property->name().c_str());
9079 // Perform a TLS relocation.
9081 template<bool big_endian>
9082 inline typename Arm_relocate_functions<big_endian>::Status
9083 Target_arm<big_endian>::Relocate::relocate_tls(
9084 const Relocate_info<32, big_endian>* relinfo,
9085 Target_arm<big_endian>* target,
9087 const elfcpp::Rel<32, big_endian>& rel,
9088 unsigned int r_type,
9089 const Sized_symbol<32>* gsym,
9090 const Symbol_value<32>* psymval,
9091 unsigned char* view,
9092 elfcpp::Elf_types<32>::Elf_Addr address,
9093 section_size_type /*view_size*/ )
9095 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
9096 typedef Relocate_functions<32, big_endian> RelocFuncs;
9097 Output_segment* tls_segment = relinfo->layout->tls_segment();
9099 const Sized_relobj<32, big_endian>* object = relinfo->object;
9101 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
9103 const bool is_final = (gsym == NULL
9104 ? !parameters->options().shared()
9105 : gsym->final_value_is_known());
9106 const tls::Tls_optimization optimized_type
9107 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
9110 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
9112 unsigned int got_type = GOT_TYPE_TLS_PAIR;
9113 unsigned int got_offset;
9116 gold_assert(gsym->has_got_offset(got_type));
9117 got_offset = gsym->got_offset(got_type) - target->got_size();
9121 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9122 gold_assert(object->local_has_got_offset(r_sym, got_type));
9123 got_offset = (object->local_got_offset(r_sym, got_type)
9124 - target->got_size());
9126 if (optimized_type == tls::TLSOPT_NONE)
9128 Arm_address got_entry =
9129 target->got_plt_section()->address() + got_offset;
9131 // Relocate the field with the PC relative offset of the pair of
9133 RelocFuncs::pcrel32(view, got_entry, address);
9134 return ArmRelocFuncs::STATUS_OKAY;
9139 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
9140 if (optimized_type == tls::TLSOPT_NONE)
9142 // Relocate the field with the offset of the GOT entry for
9143 // the module index.
9144 unsigned int got_offset;
9145 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
9146 - target->got_size());
9147 Arm_address got_entry =
9148 target->got_plt_section()->address() + got_offset;
9150 // Relocate the field with the PC relative offset of the pair of
9152 RelocFuncs::pcrel32(view, got_entry, address);
9153 return ArmRelocFuncs::STATUS_OKAY;
9157 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
9158 RelocFuncs::rel32(view, value);
9159 return ArmRelocFuncs::STATUS_OKAY;
9161 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
9162 if (optimized_type == tls::TLSOPT_NONE)
9164 // Relocate the field with the offset of the GOT entry for
9165 // the tp-relative offset of the symbol.
9166 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
9167 unsigned int got_offset;
9170 gold_assert(gsym->has_got_offset(got_type));
9171 got_offset = gsym->got_offset(got_type);
9175 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
9176 gold_assert(object->local_has_got_offset(r_sym, got_type));
9177 got_offset = object->local_got_offset(r_sym, got_type);
9180 // All GOT offsets are relative to the end of the GOT.
9181 got_offset -= target->got_size();
9183 Arm_address got_entry =
9184 target->got_plt_section()->address() + got_offset;
9186 // Relocate the field with the PC relative offset of the GOT entry.
9187 RelocFuncs::pcrel32(view, got_entry, address);
9188 return ArmRelocFuncs::STATUS_OKAY;
9192 case elfcpp::R_ARM_TLS_LE32: // Local-exec
9193 // If we're creating a shared library, a dynamic relocation will
9194 // have been created for this location, so do not apply it now.
9195 if (!parameters->options().shared())
9197 gold_assert(tls_segment != NULL);
9199 // $tp points to the TCB, which is followed by the TLS, so we
9200 // need to add TCB size to the offset.
9201 Arm_address aligned_tcb_size =
9202 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
9203 RelocFuncs::rel32(view, value + aligned_tcb_size);
9206 return ArmRelocFuncs::STATUS_OKAY;
9212 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
9213 _("unsupported reloc %u"),
9215 return ArmRelocFuncs::STATUS_BAD_RELOC;
9218 // Relocate section data.
9220 template<bool big_endian>
9222 Target_arm<big_endian>::relocate_section(
9223 const Relocate_info<32, big_endian>* relinfo,
9224 unsigned int sh_type,
9225 const unsigned char* prelocs,
9227 Output_section* output_section,
9228 bool needs_special_offset_handling,
9229 unsigned char* view,
9230 Arm_address address,
9231 section_size_type view_size,
9232 const Reloc_symbol_changes* reloc_symbol_changes)
9234 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
9235 gold_assert(sh_type == elfcpp::SHT_REL);
9237 // See if we are relocating a relaxed input section. If so, the view
9238 // covers the whole output section and we need to adjust accordingly.
9239 if (needs_special_offset_handling)
9241 const Output_relaxed_input_section* poris =
9242 output_section->find_relaxed_input_section(relinfo->object,
9243 relinfo->data_shndx);
9246 Arm_address section_address = poris->address();
9247 section_size_type section_size = poris->data_size();
9249 gold_assert((section_address >= address)
9250 && ((section_address + section_size)
9251 <= (address + view_size)));
9253 off_t offset = section_address - address;
9256 view_size = section_size;
9260 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
9267 needs_special_offset_handling,
9271 reloc_symbol_changes);
9274 // Return the size of a relocation while scanning during a relocatable
9277 template<bool big_endian>
9279 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
9280 unsigned int r_type,
9283 r_type = get_real_reloc_type(r_type);
9284 const Arm_reloc_property* arp =
9285 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9290 std::string reloc_name =
9291 arm_reloc_property_table->reloc_name_in_error_message(r_type);
9292 gold_error(_("%s: unexpected %s in object file"),
9293 object->name().c_str(), reloc_name.c_str());
9298 // Scan the relocs during a relocatable link.
9300 template<bool big_endian>
9302 Target_arm<big_endian>::scan_relocatable_relocs(
9303 Symbol_table* symtab,
9305 Sized_relobj<32, big_endian>* object,
9306 unsigned int data_shndx,
9307 unsigned int sh_type,
9308 const unsigned char* prelocs,
9310 Output_section* output_section,
9311 bool needs_special_offset_handling,
9312 size_t local_symbol_count,
9313 const unsigned char* plocal_symbols,
9314 Relocatable_relocs* rr)
9316 gold_assert(sh_type == elfcpp::SHT_REL);
9318 typedef Arm_scan_relocatable_relocs<big_endian, elfcpp::SHT_REL,
9319 Relocatable_size_for_reloc> Scan_relocatable_relocs;
9321 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
9322 Scan_relocatable_relocs>(
9330 needs_special_offset_handling,
9336 // Relocate a section during a relocatable link.
9338 template<bool big_endian>
9340 Target_arm<big_endian>::relocate_for_relocatable(
9341 const Relocate_info<32, big_endian>* relinfo,
9342 unsigned int sh_type,
9343 const unsigned char* prelocs,
9345 Output_section* output_section,
9346 off_t offset_in_output_section,
9347 const Relocatable_relocs* rr,
9348 unsigned char* view,
9349 Arm_address view_address,
9350 section_size_type view_size,
9351 unsigned char* reloc_view,
9352 section_size_type reloc_view_size)
9354 gold_assert(sh_type == elfcpp::SHT_REL);
9356 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
9361 offset_in_output_section,
9370 // Perform target-specific processing in a relocatable link. This is
9371 // only used if we use the relocation strategy RELOC_SPECIAL.
9373 template<bool big_endian>
9375 Target_arm<big_endian>::relocate_special_relocatable(
9376 const Relocate_info<32, big_endian>* relinfo,
9377 unsigned int sh_type,
9378 const unsigned char* preloc_in,
9380 Output_section* output_section,
9381 off_t offset_in_output_section,
9382 unsigned char* view,
9383 elfcpp::Elf_types<32>::Elf_Addr view_address,
9385 unsigned char* preloc_out)
9387 // We can only handle REL type relocation sections.
9388 gold_assert(sh_type == elfcpp::SHT_REL);
9390 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc Reltype;
9391 typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc_write
9393 const Arm_address invalid_address = static_cast<Arm_address>(0) - 1;
9395 const Arm_relobj<big_endian>* object =
9396 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9397 const unsigned int local_count = object->local_symbol_count();
9399 Reltype reloc(preloc_in);
9400 Reltype_write reloc_write(preloc_out);
9402 elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
9403 const unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
9404 const unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
9406 const Arm_reloc_property* arp =
9407 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9408 gold_assert(arp != NULL);
9410 // Get the new symbol index.
9411 // We only use RELOC_SPECIAL strategy in local relocations.
9412 gold_assert(r_sym < local_count);
9414 // We are adjusting a section symbol. We need to find
9415 // the symbol table index of the section symbol for
9416 // the output section corresponding to input section
9417 // in which this symbol is defined.
9419 unsigned int shndx = object->local_symbol_input_shndx(r_sym, &is_ordinary);
9420 gold_assert(is_ordinary);
9421 Output_section* os = object->output_section(shndx);
9422 gold_assert(os != NULL);
9423 gold_assert(os->needs_symtab_index());
9424 unsigned int new_symndx = os->symtab_index();
9426 // Get the new offset--the location in the output section where
9427 // this relocation should be applied.
9429 Arm_address offset = reloc.get_r_offset();
9430 Arm_address new_offset;
9431 if (offset_in_output_section != invalid_address)
9432 new_offset = offset + offset_in_output_section;
9435 section_offset_type sot_offset =
9436 convert_types<section_offset_type, Arm_address>(offset);
9437 section_offset_type new_sot_offset =
9438 output_section->output_offset(object, relinfo->data_shndx,
9440 gold_assert(new_sot_offset != -1);
9441 new_offset = new_sot_offset;
9444 // In an object file, r_offset is an offset within the section.
9445 // In an executable or dynamic object, generated by
9446 // --emit-relocs, r_offset is an absolute address.
9447 if (!parameters->options().relocatable())
9449 new_offset += view_address;
9450 if (offset_in_output_section != invalid_address)
9451 new_offset -= offset_in_output_section;
9454 reloc_write.put_r_offset(new_offset);
9455 reloc_write.put_r_info(elfcpp::elf_r_info<32>(new_symndx, r_type));
9457 // Handle the reloc addend.
9458 // The relocation uses a section symbol in the input file.
9459 // We are adjusting it to use a section symbol in the output
9460 // file. The input section symbol refers to some address in
9461 // the input section. We need the relocation in the output
9462 // file to refer to that same address. This adjustment to
9463 // the addend is the same calculation we use for a simple
9464 // absolute relocation for the input section symbol.
9466 const Symbol_value<32>* psymval = object->local_symbol(r_sym);
9468 // Handle THUMB bit.
9469 Symbol_value<32> symval;
9470 Arm_address thumb_bit =
9471 object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
9473 && arp->uses_thumb_bit()
9474 && ((psymval->value(object, 0) & 1) != 0))
9476 Arm_address stripped_value =
9477 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
9478 symval.set_output_value(stripped_value);
9482 unsigned char* paddend = view + offset;
9483 typename Arm_relocate_functions<big_endian>::Status reloc_status =
9484 Arm_relocate_functions<big_endian>::STATUS_OKAY;
9487 case elfcpp::R_ARM_ABS8:
9488 reloc_status = Arm_relocate_functions<big_endian>::abs8(paddend, object,
9492 case elfcpp::R_ARM_ABS12:
9493 reloc_status = Arm_relocate_functions<big_endian>::abs12(paddend, object,
9497 case elfcpp::R_ARM_ABS16:
9498 reloc_status = Arm_relocate_functions<big_endian>::abs16(paddend, object,
9502 case elfcpp::R_ARM_THM_ABS5:
9503 reloc_status = Arm_relocate_functions<big_endian>::thm_abs5(paddend,
9508 case elfcpp::R_ARM_MOVW_ABS_NC:
9509 case elfcpp::R_ARM_MOVW_PREL_NC:
9510 case elfcpp::R_ARM_MOVW_BREL_NC:
9511 case elfcpp::R_ARM_MOVW_BREL:
9512 reloc_status = Arm_relocate_functions<big_endian>::movw(
9513 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9516 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
9517 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
9518 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
9519 case elfcpp::R_ARM_THM_MOVW_BREL:
9520 reloc_status = Arm_relocate_functions<big_endian>::thm_movw(
9521 paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
9524 case elfcpp::R_ARM_THM_CALL:
9525 case elfcpp::R_ARM_THM_XPC22:
9526 case elfcpp::R_ARM_THM_JUMP24:
9528 Arm_relocate_functions<big_endian>::thumb_branch_common(
9529 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9533 case elfcpp::R_ARM_PLT32:
9534 case elfcpp::R_ARM_CALL:
9535 case elfcpp::R_ARM_JUMP24:
9536 case elfcpp::R_ARM_XPC25:
9538 Arm_relocate_functions<big_endian>::arm_branch_common(
9539 r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
9543 case elfcpp::R_ARM_THM_JUMP19:
9545 Arm_relocate_functions<big_endian>::thm_jump19(paddend, object,
9546 psymval, 0, thumb_bit);
9549 case elfcpp::R_ARM_THM_JUMP6:
9551 Arm_relocate_functions<big_endian>::thm_jump6(paddend, object, psymval,
9555 case elfcpp::R_ARM_THM_JUMP8:
9557 Arm_relocate_functions<big_endian>::thm_jump8(paddend, object, psymval,
9561 case elfcpp::R_ARM_THM_JUMP11:
9563 Arm_relocate_functions<big_endian>::thm_jump11(paddend, object, psymval,
9567 case elfcpp::R_ARM_PREL31:
9569 Arm_relocate_functions<big_endian>::prel31(paddend, object, psymval, 0,
9573 case elfcpp::R_ARM_THM_PC8:
9575 Arm_relocate_functions<big_endian>::thm_pc8(paddend, object, psymval,
9579 case elfcpp::R_ARM_THM_PC12:
9581 Arm_relocate_functions<big_endian>::thm_pc12(paddend, object, psymval,
9585 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
9587 Arm_relocate_functions<big_endian>::thm_alu11(paddend, object, psymval,
9591 // These relocation truncate relocation results so we cannot handle them
9592 // in a relocatable link.
9593 case elfcpp::R_ARM_MOVT_ABS:
9594 case elfcpp::R_ARM_THM_MOVT_ABS:
9595 case elfcpp::R_ARM_MOVT_PREL:
9596 case elfcpp::R_ARM_MOVT_BREL:
9597 case elfcpp::R_ARM_THM_MOVT_PREL:
9598 case elfcpp::R_ARM_THM_MOVT_BREL:
9599 case elfcpp::R_ARM_ALU_PC_G0_NC:
9600 case elfcpp::R_ARM_ALU_PC_G0:
9601 case elfcpp::R_ARM_ALU_PC_G1_NC:
9602 case elfcpp::R_ARM_ALU_PC_G1:
9603 case elfcpp::R_ARM_ALU_PC_G2:
9604 case elfcpp::R_ARM_ALU_SB_G0_NC:
9605 case elfcpp::R_ARM_ALU_SB_G0:
9606 case elfcpp::R_ARM_ALU_SB_G1_NC:
9607 case elfcpp::R_ARM_ALU_SB_G1:
9608 case elfcpp::R_ARM_ALU_SB_G2:
9609 case elfcpp::R_ARM_LDR_PC_G0:
9610 case elfcpp::R_ARM_LDR_PC_G1:
9611 case elfcpp::R_ARM_LDR_PC_G2:
9612 case elfcpp::R_ARM_LDR_SB_G0:
9613 case elfcpp::R_ARM_LDR_SB_G1:
9614 case elfcpp::R_ARM_LDR_SB_G2:
9615 case elfcpp::R_ARM_LDRS_PC_G0:
9616 case elfcpp::R_ARM_LDRS_PC_G1:
9617 case elfcpp::R_ARM_LDRS_PC_G2:
9618 case elfcpp::R_ARM_LDRS_SB_G0:
9619 case elfcpp::R_ARM_LDRS_SB_G1:
9620 case elfcpp::R_ARM_LDRS_SB_G2:
9621 case elfcpp::R_ARM_LDC_PC_G0:
9622 case elfcpp::R_ARM_LDC_PC_G1:
9623 case elfcpp::R_ARM_LDC_PC_G2:
9624 case elfcpp::R_ARM_LDC_SB_G0:
9625 case elfcpp::R_ARM_LDC_SB_G1:
9626 case elfcpp::R_ARM_LDC_SB_G2:
9627 gold_error(_("cannot handle %s in a relocatable link"),
9628 arp->name().c_str());
9635 // Report any errors.
9636 switch (reloc_status)
9638 case Arm_relocate_functions<big_endian>::STATUS_OKAY:
9640 case Arm_relocate_functions<big_endian>::STATUS_OVERFLOW:
9641 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9642 _("relocation overflow in %s"),
9643 arp->name().c_str());
9645 case Arm_relocate_functions<big_endian>::STATUS_BAD_RELOC:
9646 gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
9647 _("unexpected opcode while processing relocation %s"),
9648 arp->name().c_str());
9655 // Return the value to use for a dynamic symbol which requires special
9656 // treatment. This is how we support equality comparisons of function
9657 // pointers across shared library boundaries, as described in the
9658 // processor specific ABI supplement.
9660 template<bool big_endian>
9662 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
9664 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
9665 return this->plt_section()->address() + gsym->plt_offset();
9668 // Map platform-specific relocs to real relocs
9670 template<bool big_endian>
9672 Target_arm<big_endian>::get_real_reloc_type(unsigned int r_type)
9676 case elfcpp::R_ARM_TARGET1:
9677 // This is either R_ARM_ABS32 or R_ARM_REL32;
9678 return elfcpp::R_ARM_ABS32;
9680 case elfcpp::R_ARM_TARGET2:
9681 // This can be any reloc type but ususally is R_ARM_GOT_PREL
9682 return elfcpp::R_ARM_GOT_PREL;
9689 // Whether if two EABI versions V1 and V2 are compatible.
9691 template<bool big_endian>
9693 Target_arm<big_endian>::are_eabi_versions_compatible(
9694 elfcpp::Elf_Word v1,
9695 elfcpp::Elf_Word v2)
9697 // v4 and v5 are the same spec before and after it was released,
9698 // so allow mixing them.
9699 if ((v1 == elfcpp::EF_ARM_EABI_UNKNOWN || v2 == elfcpp::EF_ARM_EABI_UNKNOWN)
9700 || (v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
9701 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
9707 // Combine FLAGS from an input object called NAME and the processor-specific
9708 // flags in the ELF header of the output. Much of this is adapted from the
9709 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
9710 // in bfd/elf32-arm.c.
9712 template<bool big_endian>
9714 Target_arm<big_endian>::merge_processor_specific_flags(
9715 const std::string& name,
9716 elfcpp::Elf_Word flags)
9718 if (this->are_processor_specific_flags_set())
9720 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
9722 // Nothing to merge if flags equal to those in output.
9723 if (flags == out_flags)
9726 // Complain about various flag mismatches.
9727 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
9728 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
9729 if (!this->are_eabi_versions_compatible(version1, version2)
9730 && parameters->options().warn_mismatch())
9731 gold_error(_("Source object %s has EABI version %d but output has "
9732 "EABI version %d."),
9734 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
9735 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
9739 // If the input is the default architecture and had the default
9740 // flags then do not bother setting the flags for the output
9741 // architecture, instead allow future merges to do this. If no
9742 // future merges ever set these flags then they will retain their
9743 // uninitialised values, which surprise surprise, correspond
9744 // to the default values.
9748 // This is the first time, just copy the flags.
9749 // We only copy the EABI version for now.
9750 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
9754 // Adjust ELF file header.
9755 template<bool big_endian>
9757 Target_arm<big_endian>::do_adjust_elf_header(
9758 unsigned char* view,
9761 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
9763 elfcpp::Ehdr<32, big_endian> ehdr(view);
9764 unsigned char e_ident[elfcpp::EI_NIDENT];
9765 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
9767 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
9768 == elfcpp::EF_ARM_EABI_UNKNOWN)
9769 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
9771 e_ident[elfcpp::EI_OSABI] = 0;
9772 e_ident[elfcpp::EI_ABIVERSION] = 0;
9774 // FIXME: Do EF_ARM_BE8 adjustment.
9776 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
9777 oehdr.put_e_ident(e_ident);
9780 // do_make_elf_object to override the same function in the base class.
9781 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
9782 // to store ARM specific information. Hence we need to have our own
9783 // ELF object creation.
9785 template<bool big_endian>
9787 Target_arm<big_endian>::do_make_elf_object(
9788 const std::string& name,
9789 Input_file* input_file,
9790 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
9792 int et = ehdr.get_e_type();
9793 if (et == elfcpp::ET_REL)
9795 Arm_relobj<big_endian>* obj =
9796 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
9800 else if (et == elfcpp::ET_DYN)
9802 Sized_dynobj<32, big_endian>* obj =
9803 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
9809 gold_error(_("%s: unsupported ELF file type %d"),
9815 // Read the architecture from the Tag_also_compatible_with attribute, if any.
9816 // Returns -1 if no architecture could be read.
9817 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
9819 template<bool big_endian>
9821 Target_arm<big_endian>::get_secondary_compatible_arch(
9822 const Attributes_section_data* pasd)
9824 const Object_attribute* known_attributes =
9825 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9827 // Note: the tag and its argument below are uleb128 values, though
9828 // currently-defined values fit in one byte for each.
9829 const std::string& sv =
9830 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
9832 && sv.data()[0] == elfcpp::Tag_CPU_arch
9833 && (sv.data()[1] & 128) != 128)
9834 return sv.data()[1];
9836 // This tag is "safely ignorable", so don't complain if it looks funny.
9840 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
9841 // The tag is removed if ARCH is -1.
9842 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
9844 template<bool big_endian>
9846 Target_arm<big_endian>::set_secondary_compatible_arch(
9847 Attributes_section_data* pasd,
9850 Object_attribute* known_attributes =
9851 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9855 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
9859 // Note: the tag and its argument below are uleb128 values, though
9860 // currently-defined values fit in one byte for each.
9862 sv[0] = elfcpp::Tag_CPU_arch;
9863 gold_assert(arch != 0);
9867 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
9870 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
9872 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
9874 template<bool big_endian>
9876 Target_arm<big_endian>::tag_cpu_arch_combine(
9879 int* secondary_compat_out,
9881 int secondary_compat)
9883 #define T(X) elfcpp::TAG_CPU_ARCH_##X
9884 static const int v6t2[] =
9896 static const int v6k[] =
9909 static const int v7[] =
9923 static const int v6_m[] =
9938 static const int v6s_m[] =
9954 static const int v7e_m[] =
9971 static const int v4t_plus_v6_m[] =
9987 T(V4T_PLUS_V6_M) // V4T plus V6_M.
9989 static const int* comb[] =
9997 // Pseudo-architecture.
10001 // Check we've not got a higher architecture than we know about.
10003 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
10005 gold_error(_("%s: unknown CPU architecture"), name);
10009 // Override old tag if we have a Tag_also_compatible_with on the output.
10011 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
10012 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
10013 oldtag = T(V4T_PLUS_V6_M);
10015 // And override the new tag if we have a Tag_also_compatible_with on the
10018 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
10019 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
10020 newtag = T(V4T_PLUS_V6_M);
10022 // Architectures before V6KZ add features monotonically.
10023 int tagh = std::max(oldtag, newtag);
10024 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
10027 int tagl = std::min(oldtag, newtag);
10028 int result = comb[tagh - T(V6T2)][tagl];
10030 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
10031 // as the canonical version.
10032 if (result == T(V4T_PLUS_V6_M))
10035 *secondary_compat_out = T(V6_M);
10038 *secondary_compat_out = -1;
10042 gold_error(_("%s: conflicting CPU architectures %d/%d"),
10043 name, oldtag, newtag);
10051 // Helper to print AEABI enum tag value.
10053 template<bool big_endian>
10055 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
10057 static const char* aeabi_enum_names[] =
10058 { "", "variable-size", "32-bit", "" };
10059 const size_t aeabi_enum_names_size =
10060 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
10062 if (value < aeabi_enum_names_size)
10063 return std::string(aeabi_enum_names[value]);
10067 sprintf(buffer, "<unknown value %u>", value);
10068 return std::string(buffer);
10072 // Return the string value to store in TAG_CPU_name.
10074 template<bool big_endian>
10076 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
10078 static const char* name_table[] = {
10079 // These aren't real CPU names, but we can't guess
10080 // that from the architecture version alone.
10096 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
10098 if (value < name_table_size)
10099 return std::string(name_table[value]);
10103 sprintf(buffer, "<unknown CPU value %u>", value);
10104 return std::string(buffer);
10108 // Merge object attributes from input file called NAME with those of the
10109 // output. The input object attributes are in the object pointed by PASD.
10111 template<bool big_endian>
10113 Target_arm<big_endian>::merge_object_attributes(
10115 const Attributes_section_data* pasd)
10117 // Return if there is no attributes section data.
10121 // If output has no object attributes, just copy.
10122 const int vendor = Object_attribute::OBJ_ATTR_PROC;
10123 if (this->attributes_section_data_ == NULL)
10125 this->attributes_section_data_ = new Attributes_section_data(*pasd);
10126 Object_attribute* out_attr =
10127 this->attributes_section_data_->known_attributes(vendor);
10129 // We do not output objects with Tag_MPextension_use_legacy - we move
10130 // the attribute's value to Tag_MPextension_use. */
10131 if (out_attr[elfcpp::Tag_MPextension_use_legacy].int_value() != 0)
10133 if (out_attr[elfcpp::Tag_MPextension_use].int_value() != 0
10134 && out_attr[elfcpp::Tag_MPextension_use_legacy].int_value()
10135 != out_attr[elfcpp::Tag_MPextension_use].int_value())
10137 gold_error(_("%s has both the current and legacy "
10138 "Tag_MPextension_use attributes"),
10142 out_attr[elfcpp::Tag_MPextension_use] =
10143 out_attr[elfcpp::Tag_MPextension_use_legacy];
10144 out_attr[elfcpp::Tag_MPextension_use_legacy].set_type(0);
10145 out_attr[elfcpp::Tag_MPextension_use_legacy].set_int_value(0);
10151 const Object_attribute* in_attr = pasd->known_attributes(vendor);
10152 Object_attribute* out_attr =
10153 this->attributes_section_data_->known_attributes(vendor);
10155 // This needs to happen before Tag_ABI_FP_number_model is merged. */
10156 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
10157 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
10159 // Ignore mismatches if the object doesn't use floating point. */
10160 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
10161 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
10162 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
10163 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0
10164 && parameters->options().warn_mismatch())
10165 gold_error(_("%s uses VFP register arguments, output does not"),
10169 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
10171 // Merge this attribute with existing attributes.
10174 case elfcpp::Tag_CPU_raw_name:
10175 case elfcpp::Tag_CPU_name:
10176 // These are merged after Tag_CPU_arch.
10179 case elfcpp::Tag_ABI_optimization_goals:
10180 case elfcpp::Tag_ABI_FP_optimization_goals:
10181 // Use the first value seen.
10184 case elfcpp::Tag_CPU_arch:
10186 unsigned int saved_out_attr = out_attr->int_value();
10187 // Merge Tag_CPU_arch and Tag_also_compatible_with.
10188 int secondary_compat =
10189 this->get_secondary_compatible_arch(pasd);
10190 int secondary_compat_out =
10191 this->get_secondary_compatible_arch(
10192 this->attributes_section_data_);
10193 out_attr[i].set_int_value(
10194 tag_cpu_arch_combine(name, out_attr[i].int_value(),
10195 &secondary_compat_out,
10196 in_attr[i].int_value(),
10197 secondary_compat));
10198 this->set_secondary_compatible_arch(this->attributes_section_data_,
10199 secondary_compat_out);
10201 // Merge Tag_CPU_name and Tag_CPU_raw_name.
10202 if (out_attr[i].int_value() == saved_out_attr)
10203 ; // Leave the names alone.
10204 else if (out_attr[i].int_value() == in_attr[i].int_value())
10206 // The output architecture has been changed to match the
10207 // input architecture. Use the input names.
10208 out_attr[elfcpp::Tag_CPU_name].set_string_value(
10209 in_attr[elfcpp::Tag_CPU_name].string_value());
10210 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
10211 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
10215 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
10216 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
10219 // If we still don't have a value for Tag_CPU_name,
10220 // make one up now. Tag_CPU_raw_name remains blank.
10221 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
10223 const std::string cpu_name =
10224 this->tag_cpu_name_value(out_attr[i].int_value());
10225 // FIXME: If we see an unknown CPU, this will be set
10226 // to "<unknown CPU n>", where n is the attribute value.
10227 // This is different from BFD, which leaves the name alone.
10228 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
10233 case elfcpp::Tag_ARM_ISA_use:
10234 case elfcpp::Tag_THUMB_ISA_use:
10235 case elfcpp::Tag_WMMX_arch:
10236 case elfcpp::Tag_Advanced_SIMD_arch:
10237 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
10238 case elfcpp::Tag_ABI_FP_rounding:
10239 case elfcpp::Tag_ABI_FP_exceptions:
10240 case elfcpp::Tag_ABI_FP_user_exceptions:
10241 case elfcpp::Tag_ABI_FP_number_model:
10242 case elfcpp::Tag_VFP_HP_extension:
10243 case elfcpp::Tag_CPU_unaligned_access:
10244 case elfcpp::Tag_T2EE_use:
10245 case elfcpp::Tag_Virtualization_use:
10246 case elfcpp::Tag_MPextension_use:
10247 // Use the largest value specified.
10248 if (in_attr[i].int_value() > out_attr[i].int_value())
10249 out_attr[i].set_int_value(in_attr[i].int_value());
10252 case elfcpp::Tag_ABI_align8_preserved:
10253 case elfcpp::Tag_ABI_PCS_RO_data:
10254 // Use the smallest value specified.
10255 if (in_attr[i].int_value() < out_attr[i].int_value())
10256 out_attr[i].set_int_value(in_attr[i].int_value());
10259 case elfcpp::Tag_ABI_align8_needed:
10260 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
10261 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
10262 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
10265 // This error message should be enabled once all non-conformant
10266 // binaries in the toolchain have had the attributes set
10268 // gold_error(_("output 8-byte data alignment conflicts with %s"),
10272 case elfcpp::Tag_ABI_FP_denormal:
10273 case elfcpp::Tag_ABI_PCS_GOT_use:
10275 // These tags have 0 = don't care, 1 = strong requirement,
10276 // 2 = weak requirement.
10277 static const int order_021[3] = {0, 2, 1};
10279 // Use the "greatest" from the sequence 0, 2, 1, or the largest
10280 // value if greater than 2 (for future-proofing).
10281 if ((in_attr[i].int_value() > 2
10282 && in_attr[i].int_value() > out_attr[i].int_value())
10283 || (in_attr[i].int_value() <= 2
10284 && out_attr[i].int_value() <= 2
10285 && (order_021[in_attr[i].int_value()]
10286 > order_021[out_attr[i].int_value()])))
10287 out_attr[i].set_int_value(in_attr[i].int_value());
10291 case elfcpp::Tag_CPU_arch_profile:
10292 if (out_attr[i].int_value() != in_attr[i].int_value())
10294 // 0 will merge with anything.
10295 // 'A' and 'S' merge to 'A'.
10296 // 'R' and 'S' merge to 'R'.
10297 // 'M' and 'A|R|S' is an error.
10298 if (out_attr[i].int_value() == 0
10299 || (out_attr[i].int_value() == 'S'
10300 && (in_attr[i].int_value() == 'A'
10301 || in_attr[i].int_value() == 'R')))
10302 out_attr[i].set_int_value(in_attr[i].int_value());
10303 else if (in_attr[i].int_value() == 0
10304 || (in_attr[i].int_value() == 'S'
10305 && (out_attr[i].int_value() == 'A'
10306 || out_attr[i].int_value() == 'R')))
10308 else if (parameters->options().warn_mismatch())
10311 (_("conflicting architecture profiles %c/%c"),
10312 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
10313 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
10317 case elfcpp::Tag_VFP_arch:
10319 static const struct
10323 } vfp_versions[7] =
10334 // Values greater than 6 aren't defined, so just pick the
10336 if (in_attr[i].int_value() > 6
10337 && in_attr[i].int_value() > out_attr[i].int_value())
10339 *out_attr = *in_attr;
10342 // The output uses the superset of input features
10343 // (ISA version) and registers.
10344 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
10345 vfp_versions[out_attr[i].int_value()].ver);
10346 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
10347 vfp_versions[out_attr[i].int_value()].regs);
10348 // This assumes all possible supersets are also a valid
10351 for (newval = 6; newval > 0; newval--)
10353 if (regs == vfp_versions[newval].regs
10354 && ver == vfp_versions[newval].ver)
10357 out_attr[i].set_int_value(newval);
10360 case elfcpp::Tag_PCS_config:
10361 if (out_attr[i].int_value() == 0)
10362 out_attr[i].set_int_value(in_attr[i].int_value());
10363 else if (in_attr[i].int_value() != 0
10364 && out_attr[i].int_value() != 0
10365 && parameters->options().warn_mismatch())
10367 // It's sometimes ok to mix different configs, so this is only
10369 gold_warning(_("%s: conflicting platform configuration"), name);
10372 case elfcpp::Tag_ABI_PCS_R9_use:
10373 if (in_attr[i].int_value() != out_attr[i].int_value()
10374 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
10375 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused
10376 && parameters->options().warn_mismatch())
10378 gold_error(_("%s: conflicting use of R9"), name);
10380 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
10381 out_attr[i].set_int_value(in_attr[i].int_value());
10383 case elfcpp::Tag_ABI_PCS_RW_data:
10384 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
10385 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10386 != elfcpp::AEABI_R9_SB)
10387 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
10388 != elfcpp::AEABI_R9_unused)
10389 && parameters->options().warn_mismatch())
10391 gold_error(_("%s: SB relative addressing conflicts with use "
10395 // Use the smallest value specified.
10396 if (in_attr[i].int_value() < out_attr[i].int_value())
10397 out_attr[i].set_int_value(in_attr[i].int_value());
10399 case elfcpp::Tag_ABI_PCS_wchar_t:
10400 if (out_attr[i].int_value()
10401 && in_attr[i].int_value()
10402 && out_attr[i].int_value() != in_attr[i].int_value()
10403 && parameters->options().warn_mismatch()
10404 && parameters->options().wchar_size_warning())
10406 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
10407 "use %u-byte wchar_t; use of wchar_t values "
10408 "across objects may fail"),
10409 name, in_attr[i].int_value(),
10410 out_attr[i].int_value());
10412 else if (in_attr[i].int_value() && !out_attr[i].int_value())
10413 out_attr[i].set_int_value(in_attr[i].int_value());
10415 case elfcpp::Tag_ABI_enum_size:
10416 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
10418 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
10419 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
10421 // The existing object is compatible with anything.
10422 // Use whatever requirements the new object has.
10423 out_attr[i].set_int_value(in_attr[i].int_value());
10425 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
10426 && out_attr[i].int_value() != in_attr[i].int_value()
10427 && parameters->options().warn_mismatch()
10428 && parameters->options().enum_size_warning())
10430 unsigned int in_value = in_attr[i].int_value();
10431 unsigned int out_value = out_attr[i].int_value();
10432 gold_warning(_("%s uses %s enums yet the output is to use "
10433 "%s enums; use of enum values across objects "
10436 this->aeabi_enum_name(in_value).c_str(),
10437 this->aeabi_enum_name(out_value).c_str());
10441 case elfcpp::Tag_ABI_VFP_args:
10444 case elfcpp::Tag_ABI_WMMX_args:
10445 if (in_attr[i].int_value() != out_attr[i].int_value()
10446 && parameters->options().warn_mismatch())
10448 gold_error(_("%s uses iWMMXt register arguments, output does "
10453 case Object_attribute::Tag_compatibility:
10454 // Merged in target-independent code.
10456 case elfcpp::Tag_ABI_HardFP_use:
10457 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
10458 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
10459 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
10460 out_attr[i].set_int_value(3);
10461 else if (in_attr[i].int_value() > out_attr[i].int_value())
10462 out_attr[i].set_int_value(in_attr[i].int_value());
10464 case elfcpp::Tag_ABI_FP_16bit_format:
10465 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
10467 if (in_attr[i].int_value() != out_attr[i].int_value()
10468 && parameters->options().warn_mismatch())
10469 gold_error(_("fp16 format mismatch between %s and output"),
10472 if (in_attr[i].int_value() != 0)
10473 out_attr[i].set_int_value(in_attr[i].int_value());
10476 case elfcpp::Tag_DIV_use:
10477 // This tag is set to zero if we can use UDIV and SDIV in Thumb
10478 // mode on a v7-M or v7-R CPU; to one if we can not use UDIV or
10479 // SDIV at all; and to two if we can use UDIV or SDIV on a v7-A
10480 // CPU. We will merge as follows: If the input attribute's value
10481 // is one then the output attribute's value remains unchanged. If
10482 // the input attribute's value is zero or two then if the output
10483 // attribute's value is one the output value is set to the input
10484 // value, otherwise the output value must be the same as the
10486 if (in_attr[i].int_value() != 1 && out_attr[i].int_value() != 1)
10488 if (in_attr[i].int_value() != out_attr[i].int_value())
10490 gold_error(_("DIV usage mismatch between %s and output"),
10495 if (in_attr[i].int_value() != 1)
10496 out_attr[i].set_int_value(in_attr[i].int_value());
10500 case elfcpp::Tag_MPextension_use_legacy:
10501 // We don't output objects with Tag_MPextension_use_legacy - we
10502 // move the value to Tag_MPextension_use.
10503 if (in_attr[i].int_value() != 0
10504 && in_attr[elfcpp::Tag_MPextension_use].int_value() != 0)
10506 if (in_attr[elfcpp::Tag_MPextension_use].int_value()
10507 != in_attr[i].int_value())
10509 gold_error(_("%s has has both the current and legacy "
10510 "Tag_MPextension_use attributes"),
10515 if (in_attr[i].int_value()
10516 > out_attr[elfcpp::Tag_MPextension_use].int_value())
10517 out_attr[elfcpp::Tag_MPextension_use] = in_attr[i];
10521 case elfcpp::Tag_nodefaults:
10522 // This tag is set if it exists, but the value is unused (and is
10523 // typically zero). We don't actually need to do anything here -
10524 // the merge happens automatically when the type flags are merged
10527 case elfcpp::Tag_also_compatible_with:
10528 // Already done in Tag_CPU_arch.
10530 case elfcpp::Tag_conformance:
10531 // Keep the attribute if it matches. Throw it away otherwise.
10532 // No attribute means no claim to conform.
10533 if (in_attr[i].string_value() != out_attr[i].string_value())
10534 out_attr[i].set_string_value("");
10539 const char* err_object = NULL;
10541 // The "known_obj_attributes" table does contain some undefined
10542 // attributes. Ensure that there are unused.
10543 if (out_attr[i].int_value() != 0
10544 || out_attr[i].string_value() != "")
10545 err_object = "output";
10546 else if (in_attr[i].int_value() != 0
10547 || in_attr[i].string_value() != "")
10550 if (err_object != NULL
10551 && parameters->options().warn_mismatch())
10553 // Attribute numbers >=64 (mod 128) can be safely ignored.
10554 if ((i & 127) < 64)
10555 gold_error(_("%s: unknown mandatory EABI object attribute "
10559 gold_warning(_("%s: unknown EABI object attribute %d"),
10563 // Only pass on attributes that match in both inputs.
10564 if (!in_attr[i].matches(out_attr[i]))
10566 out_attr[i].set_int_value(0);
10567 out_attr[i].set_string_value("");
10572 // If out_attr was copied from in_attr then it won't have a type yet.
10573 if (in_attr[i].type() && !out_attr[i].type())
10574 out_attr[i].set_type(in_attr[i].type());
10577 // Merge Tag_compatibility attributes and any common GNU ones.
10578 this->attributes_section_data_->merge(name, pasd);
10580 // Check for any attributes not known on ARM.
10581 typedef Vendor_object_attributes::Other_attributes Other_attributes;
10582 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
10583 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
10584 Other_attributes* out_other_attributes =
10585 this->attributes_section_data_->other_attributes(vendor);
10586 Other_attributes::iterator out_iter = out_other_attributes->begin();
10588 while (in_iter != in_other_attributes->end()
10589 || out_iter != out_other_attributes->end())
10591 const char* err_object = NULL;
10594 // The tags for each list are in numerical order.
10595 // If the tags are equal, then merge.
10596 if (out_iter != out_other_attributes->end()
10597 && (in_iter == in_other_attributes->end()
10598 || in_iter->first > out_iter->first))
10600 // This attribute only exists in output. We can't merge, and we
10601 // don't know what the tag means, so delete it.
10602 err_object = "output";
10603 err_tag = out_iter->first;
10604 int saved_tag = out_iter->first;
10605 delete out_iter->second;
10606 out_other_attributes->erase(out_iter);
10607 out_iter = out_other_attributes->upper_bound(saved_tag);
10609 else if (in_iter != in_other_attributes->end()
10610 && (out_iter != out_other_attributes->end()
10611 || in_iter->first < out_iter->first))
10613 // This attribute only exists in input. We can't merge, and we
10614 // don't know what the tag means, so ignore it.
10616 err_tag = in_iter->first;
10619 else // The tags are equal.
10621 // As present, all attributes in the list are unknown, and
10622 // therefore can't be merged meaningfully.
10623 err_object = "output";
10624 err_tag = out_iter->first;
10626 // Only pass on attributes that match in both inputs.
10627 if (!in_iter->second->matches(*(out_iter->second)))
10629 // No match. Delete the attribute.
10630 int saved_tag = out_iter->first;
10631 delete out_iter->second;
10632 out_other_attributes->erase(out_iter);
10633 out_iter = out_other_attributes->upper_bound(saved_tag);
10637 // Matched. Keep the attribute and move to the next.
10643 if (err_object && parameters->options().warn_mismatch())
10645 // Attribute numbers >=64 (mod 128) can be safely ignored. */
10646 if ((err_tag & 127) < 64)
10648 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
10649 err_object, err_tag);
10653 gold_warning(_("%s: unknown EABI object attribute %d"),
10654 err_object, err_tag);
10660 // Stub-generation methods for Target_arm.
10662 // Make a new Arm_input_section object.
10664 template<bool big_endian>
10665 Arm_input_section<big_endian>*
10666 Target_arm<big_endian>::new_arm_input_section(
10668 unsigned int shndx)
10670 Section_id sid(relobj, shndx);
10672 Arm_input_section<big_endian>* arm_input_section =
10673 new Arm_input_section<big_endian>(relobj, shndx);
10674 arm_input_section->init();
10676 // Register new Arm_input_section in map for look-up.
10677 std::pair<typename Arm_input_section_map::iterator, bool> ins =
10678 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
10680 // Make sure that it we have not created another Arm_input_section
10681 // for this input section already.
10682 gold_assert(ins.second);
10684 return arm_input_section;
10687 // Find the Arm_input_section object corresponding to the SHNDX-th input
10688 // section of RELOBJ.
10690 template<bool big_endian>
10691 Arm_input_section<big_endian>*
10692 Target_arm<big_endian>::find_arm_input_section(
10694 unsigned int shndx) const
10696 Section_id sid(relobj, shndx);
10697 typename Arm_input_section_map::const_iterator p =
10698 this->arm_input_section_map_.find(sid);
10699 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
10702 // Make a new stub table.
10704 template<bool big_endian>
10705 Stub_table<big_endian>*
10706 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
10708 Stub_table<big_endian>* stub_table =
10709 new Stub_table<big_endian>(owner);
10710 this->stub_tables_.push_back(stub_table);
10712 stub_table->set_address(owner->address() + owner->data_size());
10713 stub_table->set_file_offset(owner->offset() + owner->data_size());
10714 stub_table->finalize_data_size();
10719 // Scan a relocation for stub generation.
10721 template<bool big_endian>
10723 Target_arm<big_endian>::scan_reloc_for_stub(
10724 const Relocate_info<32, big_endian>* relinfo,
10725 unsigned int r_type,
10726 const Sized_symbol<32>* gsym,
10727 unsigned int r_sym,
10728 const Symbol_value<32>* psymval,
10729 elfcpp::Elf_types<32>::Elf_Swxword addend,
10730 Arm_address address)
10732 typedef typename Target_arm<big_endian>::Relocate Relocate;
10734 const Arm_relobj<big_endian>* arm_relobj =
10735 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10737 bool target_is_thumb;
10738 Symbol_value<32> symval;
10741 // This is a global symbol. Determine if we use PLT and if the
10742 // final target is THUMB.
10743 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
10745 // This uses a PLT, change the symbol value.
10746 symval.set_output_value(this->plt_section()->address()
10747 + gsym->plt_offset());
10749 target_is_thumb = false;
10751 else if (gsym->is_undefined())
10752 // There is no need to generate a stub symbol is undefined.
10757 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
10758 || (gsym->type() == elfcpp::STT_FUNC
10759 && !gsym->is_undefined()
10760 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
10765 // This is a local symbol. Determine if the final target is THUMB.
10766 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
10769 // Strip LSB if this points to a THUMB target.
10770 const Arm_reloc_property* reloc_property =
10771 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
10772 gold_assert(reloc_property != NULL);
10773 if (target_is_thumb
10774 && reloc_property->uses_thumb_bit()
10775 && ((psymval->value(arm_relobj, 0) & 1) != 0))
10777 Arm_address stripped_value =
10778 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
10779 symval.set_output_value(stripped_value);
10783 // Get the symbol value.
10784 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
10786 // Owing to pipelining, the PC relative branches below actually skip
10787 // two instructions when the branch offset is 0.
10788 Arm_address destination;
10791 case elfcpp::R_ARM_CALL:
10792 case elfcpp::R_ARM_JUMP24:
10793 case elfcpp::R_ARM_PLT32:
10795 destination = value + addend + 8;
10797 case elfcpp::R_ARM_THM_CALL:
10798 case elfcpp::R_ARM_THM_XPC22:
10799 case elfcpp::R_ARM_THM_JUMP24:
10800 case elfcpp::R_ARM_THM_JUMP19:
10802 destination = value + addend + 4;
10805 gold_unreachable();
10808 Reloc_stub* stub = NULL;
10809 Stub_type stub_type =
10810 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
10812 if (stub_type != arm_stub_none)
10814 // Try looking up an existing stub from a stub table.
10815 Stub_table<big_endian>* stub_table =
10816 arm_relobj->stub_table(relinfo->data_shndx);
10817 gold_assert(stub_table != NULL);
10819 // Locate stub by destination.
10820 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
10822 // Create a stub if there is not one already
10823 stub = stub_table->find_reloc_stub(stub_key);
10826 // create a new stub and add it to stub table.
10827 stub = this->stub_factory().make_reloc_stub(stub_type);
10828 stub_table->add_reloc_stub(stub, stub_key);
10831 // Record the destination address.
10832 stub->set_destination_address(destination
10833 | (target_is_thumb ? 1 : 0));
10836 // For Cortex-A8, we need to record a relocation at 4K page boundary.
10837 if (this->fix_cortex_a8_
10838 && (r_type == elfcpp::R_ARM_THM_JUMP24
10839 || r_type == elfcpp::R_ARM_THM_JUMP19
10840 || r_type == elfcpp::R_ARM_THM_CALL
10841 || r_type == elfcpp::R_ARM_THM_XPC22)
10842 && (address & 0xfffU) == 0xffeU)
10844 // Found a candidate. Note we haven't checked the destination is
10845 // within 4K here: if we do so (and don't create a record) we can't
10846 // tell that a branch should have been relocated when scanning later.
10847 this->cortex_a8_relocs_info_[address] =
10848 new Cortex_a8_reloc(stub, r_type,
10849 destination | (target_is_thumb ? 1 : 0));
10853 // This function scans a relocation sections for stub generation.
10854 // The template parameter Relocate must be a class type which provides
10855 // a single function, relocate(), which implements the machine
10856 // specific part of a relocation.
10858 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
10859 // SHT_REL or SHT_RELA.
10861 // PRELOCS points to the relocation data. RELOC_COUNT is the number
10862 // of relocs. OUTPUT_SECTION is the output section.
10863 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
10864 // mapped to output offsets.
10866 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
10867 // VIEW_SIZE is the size. These refer to the input section, unless
10868 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
10869 // the output section.
10871 template<bool big_endian>
10872 template<int sh_type>
10874 Target_arm<big_endian>::scan_reloc_section_for_stubs(
10875 const Relocate_info<32, big_endian>* relinfo,
10876 const unsigned char* prelocs,
10877 size_t reloc_count,
10878 Output_section* output_section,
10879 bool needs_special_offset_handling,
10880 const unsigned char* view,
10881 elfcpp::Elf_types<32>::Elf_Addr view_address,
10884 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
10885 const int reloc_size =
10886 Reloc_types<sh_type, 32, big_endian>::reloc_size;
10888 Arm_relobj<big_endian>* arm_object =
10889 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10890 unsigned int local_count = arm_object->local_symbol_count();
10892 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
10894 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
10896 Reltype reloc(prelocs);
10898 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
10899 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
10900 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
10902 r_type = this->get_real_reloc_type(r_type);
10904 // Only a few relocation types need stubs.
10905 if ((r_type != elfcpp::R_ARM_CALL)
10906 && (r_type != elfcpp::R_ARM_JUMP24)
10907 && (r_type != elfcpp::R_ARM_PLT32)
10908 && (r_type != elfcpp::R_ARM_THM_CALL)
10909 && (r_type != elfcpp::R_ARM_THM_XPC22)
10910 && (r_type != elfcpp::R_ARM_THM_JUMP24)
10911 && (r_type != elfcpp::R_ARM_THM_JUMP19)
10912 && (r_type != elfcpp::R_ARM_V4BX))
10915 section_offset_type offset =
10916 convert_to_section_size_type(reloc.get_r_offset());
10918 if (needs_special_offset_handling)
10920 offset = output_section->output_offset(relinfo->object,
10921 relinfo->data_shndx,
10927 // Create a v4bx stub if --fix-v4bx-interworking is used.
10928 if (r_type == elfcpp::R_ARM_V4BX)
10930 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
10932 // Get the BX instruction.
10933 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
10934 const Valtype* wv =
10935 reinterpret_cast<const Valtype*>(view + offset);
10936 elfcpp::Elf_types<32>::Elf_Swxword insn =
10937 elfcpp::Swap<32, big_endian>::readval(wv);
10938 const uint32_t reg = (insn & 0xf);
10942 // Try looking up an existing stub from a stub table.
10943 Stub_table<big_endian>* stub_table =
10944 arm_object->stub_table(relinfo->data_shndx);
10945 gold_assert(stub_table != NULL);
10947 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
10949 // create a new stub and add it to stub table.
10950 Arm_v4bx_stub* stub =
10951 this->stub_factory().make_arm_v4bx_stub(reg);
10952 gold_assert(stub != NULL);
10953 stub_table->add_arm_v4bx_stub(stub);
10961 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
10962 elfcpp::Elf_types<32>::Elf_Swxword addend =
10963 stub_addend_reader(r_type, view + offset, reloc);
10965 const Sized_symbol<32>* sym;
10967 Symbol_value<32> symval;
10968 const Symbol_value<32> *psymval;
10969 bool is_defined_in_discarded_section;
10970 unsigned int shndx;
10971 if (r_sym < local_count)
10974 psymval = arm_object->local_symbol(r_sym);
10976 // If the local symbol belongs to a section we are discarding,
10977 // and that section is a debug section, try to find the
10978 // corresponding kept section and map this symbol to its
10979 // counterpart in the kept section. The symbol must not
10980 // correspond to a section we are folding.
10982 shndx = psymval->input_shndx(&is_ordinary);
10983 is_defined_in_discarded_section =
10985 && shndx != elfcpp::SHN_UNDEF
10986 && !arm_object->is_section_included(shndx)
10987 && !relinfo->symtab->is_section_folded(arm_object, shndx));
10989 // We need to compute the would-be final value of this local
10991 if (!is_defined_in_discarded_section)
10993 typedef Sized_relobj<32, big_endian> ObjType;
10994 typename ObjType::Compute_final_local_value_status status =
10995 arm_object->compute_final_local_value(r_sym, psymval, &symval,
10997 if (status == ObjType::CFLV_OK)
10999 // Currently we cannot handle a branch to a target in
11000 // a merged section. If this is the case, issue an error
11001 // and also free the merge symbol value.
11002 if (!symval.has_output_value())
11004 const std::string& section_name =
11005 arm_object->section_name(shndx);
11006 arm_object->error(_("cannot handle branch to local %u "
11007 "in a merged section %s"),
11008 r_sym, section_name.c_str());
11014 // We cannot determine the final value.
11021 const Symbol* gsym;
11022 gsym = arm_object->global_symbol(r_sym);
11023 gold_assert(gsym != NULL);
11024 if (gsym->is_forwarder())
11025 gsym = relinfo->symtab->resolve_forwards(gsym);
11027 sym = static_cast<const Sized_symbol<32>*>(gsym);
11028 if (sym->has_symtab_index() && sym->symtab_index() != -1U)
11029 symval.set_output_symtab_index(sym->symtab_index());
11031 symval.set_no_output_symtab_entry();
11033 // We need to compute the would-be final value of this global
11035 const Symbol_table* symtab = relinfo->symtab;
11036 const Sized_symbol<32>* sized_symbol =
11037 symtab->get_sized_symbol<32>(gsym);
11038 Symbol_table::Compute_final_value_status status;
11039 Arm_address value =
11040 symtab->compute_final_value<32>(sized_symbol, &status);
11042 // Skip this if the symbol has not output section.
11043 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
11045 symval.set_output_value(value);
11047 if (gsym->type() == elfcpp::STT_TLS)
11048 symval.set_is_tls_symbol();
11049 else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
11050 symval.set_is_ifunc_symbol();
11053 is_defined_in_discarded_section =
11054 (gsym->is_defined_in_discarded_section()
11055 && gsym->is_undefined());
11059 Symbol_value<32> symval2;
11060 if (is_defined_in_discarded_section)
11062 if (comdat_behavior == CB_UNDETERMINED)
11064 std::string name = arm_object->section_name(relinfo->data_shndx);
11065 comdat_behavior = get_comdat_behavior(name.c_str());
11067 if (comdat_behavior == CB_PRETEND)
11069 // FIXME: This case does not work for global symbols.
11070 // We have no place to store the original section index.
11071 // Fortunately this does not matter for comdat sections,
11072 // only for sections explicitly discarded by a linker
11075 typename elfcpp::Elf_types<32>::Elf_Addr value =
11076 arm_object->map_to_kept_section(shndx, &found);
11078 symval2.set_output_value(value + psymval->input_value());
11080 symval2.set_output_value(0);
11084 if (comdat_behavior == CB_WARNING)
11085 gold_warning_at_location(relinfo, i, offset,
11086 _("relocation refers to discarded "
11088 symval2.set_output_value(0);
11090 symval2.set_no_output_symtab_entry();
11091 psymval = &symval2;
11094 // If symbol is a section symbol, we don't know the actual type of
11095 // destination. Give up.
11096 if (psymval->is_section_symbol())
11099 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
11100 addend, view_address + offset);
11104 // Scan an input section for stub generation.
11106 template<bool big_endian>
11108 Target_arm<big_endian>::scan_section_for_stubs(
11109 const Relocate_info<32, big_endian>* relinfo,
11110 unsigned int sh_type,
11111 const unsigned char* prelocs,
11112 size_t reloc_count,
11113 Output_section* output_section,
11114 bool needs_special_offset_handling,
11115 const unsigned char* view,
11116 Arm_address view_address,
11117 section_size_type view_size)
11119 if (sh_type == elfcpp::SHT_REL)
11120 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
11125 needs_special_offset_handling,
11129 else if (sh_type == elfcpp::SHT_RELA)
11130 // We do not support RELA type relocations yet. This is provided for
11132 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
11137 needs_special_offset_handling,
11142 gold_unreachable();
11145 // Group input sections for stub generation.
11147 // We goup input sections in an output sections so that the total size,
11148 // including any padding space due to alignment is smaller than GROUP_SIZE
11149 // unless the only input section in group is bigger than GROUP_SIZE already.
11150 // Then an ARM stub table is created to follow the last input section
11151 // in group. For each group an ARM stub table is created an is placed
11152 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
11153 // extend the group after the stub table.
11155 template<bool big_endian>
11157 Target_arm<big_endian>::group_sections(
11159 section_size_type group_size,
11160 bool stubs_always_after_branch)
11162 // Group input sections and insert stub table
11163 Layout::Section_list section_list;
11164 layout->get_allocated_sections(§ion_list);
11165 for (Layout::Section_list::const_iterator p = section_list.begin();
11166 p != section_list.end();
11169 Arm_output_section<big_endian>* output_section =
11170 Arm_output_section<big_endian>::as_arm_output_section(*p);
11171 output_section->group_sections(group_size, stubs_always_after_branch,
11176 // Relaxation hook. This is where we do stub generation.
11178 template<bool big_endian>
11180 Target_arm<big_endian>::do_relax(
11182 const Input_objects* input_objects,
11183 Symbol_table* symtab,
11186 // No need to generate stubs if this is a relocatable link.
11187 gold_assert(!parameters->options().relocatable());
11189 // If this is the first pass, we need to group input sections into
11191 bool done_exidx_fixup = false;
11192 typedef typename Stub_table_list::iterator Stub_table_iterator;
11195 // Determine the stub group size. The group size is the absolute
11196 // value of the parameter --stub-group-size. If --stub-group-size
11197 // is passed a negative value, we restict stubs to be always after
11198 // the stubbed branches.
11199 int32_t stub_group_size_param =
11200 parameters->options().stub_group_size();
11201 bool stubs_always_after_branch = stub_group_size_param < 0;
11202 section_size_type stub_group_size = abs(stub_group_size_param);
11204 if (stub_group_size == 1)
11207 // Thumb branch range is +-4MB has to be used as the default
11208 // maximum size (a given section can contain both ARM and Thumb
11209 // code, so the worst case has to be taken into account). If we are
11210 // fixing cortex-a8 errata, the branch range has to be even smaller,
11211 // since wide conditional branch has a range of +-1MB only.
11213 // This value is 48K less than that, which allows for 4096
11214 // 12-byte stubs. If we exceed that, then we will fail to link.
11215 // The user will have to relink with an explicit group size
11217 stub_group_size = 4145152;
11220 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
11221 // page as the first half of a 32-bit branch straddling two 4K pages.
11222 // This is a crude way of enforcing that. In addition, long conditional
11223 // branches of THUMB-2 have a range of +-1M. If we are fixing cortex-A8
11224 // erratum, limit the group size to (1M - 12k) to avoid unreachable
11225 // cortex-A8 stubs from long conditional branches.
11226 if (this->fix_cortex_a8_)
11228 stubs_always_after_branch = true;
11229 const section_size_type cortex_a8_group_size = 1024 * (1024 - 12);
11230 stub_group_size = std::max(stub_group_size, cortex_a8_group_size);
11233 group_sections(layout, stub_group_size, stubs_always_after_branch);
11235 // Also fix .ARM.exidx section coverage.
11236 Arm_output_section<big_endian>* exidx_output_section = NULL;
11237 for (Layout::Section_list::const_iterator p =
11238 layout->section_list().begin();
11239 p != layout->section_list().end();
11241 if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
11243 if (exidx_output_section == NULL)
11244 exidx_output_section =
11245 Arm_output_section<big_endian>::as_arm_output_section(*p);
11247 // We cannot handle this now.
11248 gold_error(_("multiple SHT_ARM_EXIDX sections %s and %s in a "
11249 "non-relocatable link"),
11250 exidx_output_section->name(),
11254 if (exidx_output_section != NULL)
11256 this->fix_exidx_coverage(layout, input_objects, exidx_output_section,
11258 done_exidx_fixup = true;
11263 // If this is not the first pass, addresses and file offsets have
11264 // been reset at this point, set them here.
11265 for (Stub_table_iterator sp = this->stub_tables_.begin();
11266 sp != this->stub_tables_.end();
11269 Arm_input_section<big_endian>* owner = (*sp)->owner();
11270 off_t off = align_address(owner->original_size(),
11271 (*sp)->addralign());
11272 (*sp)->set_address_and_file_offset(owner->address() + off,
11273 owner->offset() + off);
11277 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
11278 // beginning of each relaxation pass, just blow away all the stubs.
11279 // Alternatively, we could selectively remove only the stubs and reloc
11280 // information for code sections that have moved since the last pass.
11281 // That would require more book-keeping.
11282 if (this->fix_cortex_a8_)
11284 // Clear all Cortex-A8 reloc information.
11285 for (typename Cortex_a8_relocs_info::const_iterator p =
11286 this->cortex_a8_relocs_info_.begin();
11287 p != this->cortex_a8_relocs_info_.end();
11290 this->cortex_a8_relocs_info_.clear();
11292 // Remove all Cortex-A8 stubs.
11293 for (Stub_table_iterator sp = this->stub_tables_.begin();
11294 sp != this->stub_tables_.end();
11296 (*sp)->remove_all_cortex_a8_stubs();
11299 // Scan relocs for relocation stubs
11300 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11301 op != input_objects->relobj_end();
11304 Arm_relobj<big_endian>* arm_relobj =
11305 Arm_relobj<big_endian>::as_arm_relobj(*op);
11306 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
11309 // Check all stub tables to see if any of them have their data sizes
11310 // or addresses alignments changed. These are the only things that
11312 bool any_stub_table_changed = false;
11313 Unordered_set<const Output_section*> sections_needing_adjustment;
11314 for (Stub_table_iterator sp = this->stub_tables_.begin();
11315 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11318 if ((*sp)->update_data_size_and_addralign())
11320 // Update data size of stub table owner.
11321 Arm_input_section<big_endian>* owner = (*sp)->owner();
11322 uint64_t address = owner->address();
11323 off_t offset = owner->offset();
11324 owner->reset_address_and_file_offset();
11325 owner->set_address_and_file_offset(address, offset);
11327 sections_needing_adjustment.insert(owner->output_section());
11328 any_stub_table_changed = true;
11332 // Output_section_data::output_section() returns a const pointer but we
11333 // need to update output sections, so we record all output sections needing
11334 // update above and scan the sections here to find out what sections need
11336 for(Layout::Section_list::const_iterator p = layout->section_list().begin();
11337 p != layout->section_list().end();
11340 if (sections_needing_adjustment.find(*p)
11341 != sections_needing_adjustment.end())
11342 (*p)->set_section_offsets_need_adjustment();
11345 // Stop relaxation if no EXIDX fix-up and no stub table change.
11346 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
11348 // Finalize the stubs in the last relaxation pass.
11349 if (!continue_relaxation)
11351 for (Stub_table_iterator sp = this->stub_tables_.begin();
11352 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
11354 (*sp)->finalize_stubs();
11356 // Update output local symbol counts of objects if necessary.
11357 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
11358 op != input_objects->relobj_end();
11361 Arm_relobj<big_endian>* arm_relobj =
11362 Arm_relobj<big_endian>::as_arm_relobj(*op);
11364 // Update output local symbol counts. We need to discard local
11365 // symbols defined in parts of input sections that are discarded by
11367 if (arm_relobj->output_local_symbol_count_needs_update())
11368 arm_relobj->update_output_local_symbol_count();
11372 return continue_relaxation;
11375 // Relocate a stub.
11377 template<bool big_endian>
11379 Target_arm<big_endian>::relocate_stub(
11381 const Relocate_info<32, big_endian>* relinfo,
11382 Output_section* output_section,
11383 unsigned char* view,
11384 Arm_address address,
11385 section_size_type view_size)
11388 const Stub_template* stub_template = stub->stub_template();
11389 for (size_t i = 0; i < stub_template->reloc_count(); i++)
11391 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
11392 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
11394 unsigned int r_type = insn->r_type();
11395 section_size_type reloc_offset = stub_template->reloc_offset(i);
11396 section_size_type reloc_size = insn->size();
11397 gold_assert(reloc_offset + reloc_size <= view_size);
11399 // This is the address of the stub destination.
11400 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
11401 Symbol_value<32> symval;
11402 symval.set_output_value(target);
11404 // Synthesize a fake reloc just in case. We don't have a symbol so
11406 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
11407 memset(reloc_buffer, 0, sizeof(reloc_buffer));
11408 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
11409 reloc_write.put_r_offset(reloc_offset);
11410 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
11411 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
11413 relocate.relocate(relinfo, this, output_section,
11414 this->fake_relnum_for_stubs, rel, r_type,
11415 NULL, &symval, view + reloc_offset,
11416 address + reloc_offset, reloc_size);
11420 // Determine whether an object attribute tag takes an integer, a
11423 template<bool big_endian>
11425 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
11427 if (tag == Object_attribute::Tag_compatibility)
11428 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11429 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
11430 else if (tag == elfcpp::Tag_nodefaults)
11431 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
11432 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
11433 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
11434 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
11436 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
11438 return ((tag & 1) != 0
11439 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
11440 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
11443 // Reorder attributes.
11445 // The ABI defines that Tag_conformance should be emitted first, and that
11446 // Tag_nodefaults should be second (if either is defined). This sets those
11447 // two positions, and bumps up the position of all the remaining tags to
11450 template<bool big_endian>
11452 Target_arm<big_endian>::do_attributes_order(int num) const
11454 // Reorder the known object attributes in output. We want to move
11455 // Tag_conformance to position 4 and Tag_conformance to position 5
11456 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
11458 return elfcpp::Tag_conformance;
11460 return elfcpp::Tag_nodefaults;
11461 if ((num - 2) < elfcpp::Tag_nodefaults)
11463 if ((num - 1) < elfcpp::Tag_conformance)
11468 // Scan a span of THUMB code for Cortex-A8 erratum.
11470 template<bool big_endian>
11472 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
11473 Arm_relobj<big_endian>* arm_relobj,
11474 unsigned int shndx,
11475 section_size_type span_start,
11476 section_size_type span_end,
11477 const unsigned char* view,
11478 Arm_address address)
11480 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
11482 // The opcode is BLX.W, BL.W, B.W, Bcc.W
11483 // The branch target is in the same 4KB region as the
11484 // first half of the branch.
11485 // The instruction before the branch is a 32-bit
11486 // length non-branch instruction.
11487 section_size_type i = span_start;
11488 bool last_was_32bit = false;
11489 bool last_was_branch = false;
11490 while (i < span_end)
11492 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11493 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
11494 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
11495 bool is_blx = false, is_b = false;
11496 bool is_bl = false, is_bcc = false;
11498 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
11501 // Load the rest of the insn (in manual-friendly order).
11502 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
11504 // Encoding T4: B<c>.W.
11505 is_b = (insn & 0xf800d000U) == 0xf0009000U;
11506 // Encoding T1: BL<c>.W.
11507 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
11508 // Encoding T2: BLX<c>.W.
11509 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
11510 // Encoding T3: B<c>.W (not permitted in IT block).
11511 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
11512 && (insn & 0x07f00000U) != 0x03800000U);
11515 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
11517 // If this instruction is a 32-bit THUMB branch that crosses a 4K
11518 // page boundary and it follows 32-bit non-branch instruction,
11519 // we need to work around.
11520 if (is_32bit_branch
11521 && ((address + i) & 0xfffU) == 0xffeU
11523 && !last_was_branch)
11525 // Check to see if there is a relocation stub for this branch.
11526 bool force_target_arm = false;
11527 bool force_target_thumb = false;
11528 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
11529 Cortex_a8_relocs_info::const_iterator p =
11530 this->cortex_a8_relocs_info_.find(address + i);
11532 if (p != this->cortex_a8_relocs_info_.end())
11534 cortex_a8_reloc = p->second;
11535 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
11537 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11538 && !target_is_thumb)
11539 force_target_arm = true;
11540 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
11541 && target_is_thumb)
11542 force_target_thumb = true;
11546 Stub_type stub_type = arm_stub_none;
11548 // Check if we have an offending branch instruction.
11549 uint16_t upper_insn = (insn >> 16) & 0xffffU;
11550 uint16_t lower_insn = insn & 0xffffU;
11551 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
11553 if (cortex_a8_reloc != NULL
11554 && cortex_a8_reloc->reloc_stub() != NULL)
11555 // We've already made a stub for this instruction, e.g.
11556 // it's a long branch or a Thumb->ARM stub. Assume that
11557 // stub will suffice to work around the A8 erratum (see
11558 // setting of always_after_branch above).
11562 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
11564 stub_type = arm_stub_a8_veneer_b_cond;
11566 else if (is_b || is_bl || is_blx)
11568 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
11573 stub_type = (is_blx
11574 ? arm_stub_a8_veneer_blx
11576 ? arm_stub_a8_veneer_bl
11577 : arm_stub_a8_veneer_b));
11580 if (stub_type != arm_stub_none)
11582 Arm_address pc_for_insn = address + i + 4;
11584 // The original instruction is a BL, but the target is
11585 // an ARM instruction. If we were not making a stub,
11586 // the BL would have been converted to a BLX. Use the
11587 // BLX stub instead in that case.
11588 if (this->may_use_blx() && force_target_arm
11589 && stub_type == arm_stub_a8_veneer_bl)
11591 stub_type = arm_stub_a8_veneer_blx;
11595 // Conversely, if the original instruction was
11596 // BLX but the target is Thumb mode, use the BL stub.
11597 else if (force_target_thumb
11598 && stub_type == arm_stub_a8_veneer_blx)
11600 stub_type = arm_stub_a8_veneer_bl;
11608 // If we found a relocation, use the proper destination,
11609 // not the offset in the (unrelocated) instruction.
11610 // Note this is always done if we switched the stub type above.
11611 if (cortex_a8_reloc != NULL)
11612 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
11614 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
11616 // Add a new stub if destination address in in the same page.
11617 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
11619 Cortex_a8_stub* stub =
11620 this->stub_factory_.make_cortex_a8_stub(stub_type,
11624 Stub_table<big_endian>* stub_table =
11625 arm_relobj->stub_table(shndx);
11626 gold_assert(stub_table != NULL);
11627 stub_table->add_cortex_a8_stub(address + i, stub);
11632 i += insn_32bit ? 4 : 2;
11633 last_was_32bit = insn_32bit;
11634 last_was_branch = is_32bit_branch;
11638 // Apply the Cortex-A8 workaround.
11640 template<bool big_endian>
11642 Target_arm<big_endian>::apply_cortex_a8_workaround(
11643 const Cortex_a8_stub* stub,
11644 Arm_address stub_address,
11645 unsigned char* insn_view,
11646 Arm_address insn_address)
11648 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
11649 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
11650 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
11651 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
11652 off_t branch_offset = stub_address - (insn_address + 4);
11654 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
11655 switch (stub->stub_template()->type())
11657 case arm_stub_a8_veneer_b_cond:
11658 // For a conditional branch, we re-write it to be a uncondition
11659 // branch to the stub. We use the THUMB-2 encoding here.
11660 upper_insn = 0xf000U;
11661 lower_insn = 0xb800U;
11663 case arm_stub_a8_veneer_b:
11664 case arm_stub_a8_veneer_bl:
11665 case arm_stub_a8_veneer_blx:
11666 if ((lower_insn & 0x5000U) == 0x4000U)
11667 // For a BLX instruction, make sure that the relocation is
11668 // rounded up to a word boundary. This follows the semantics of
11669 // the instruction which specifies that bit 1 of the target
11670 // address will come from bit 1 of the base address.
11671 branch_offset = (branch_offset + 2) & ~3;
11673 // Put BRANCH_OFFSET back into the insn.
11674 gold_assert(!utils::has_overflow<25>(branch_offset));
11675 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
11676 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
11680 gold_unreachable();
11683 // Put the relocated value back in the object file:
11684 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
11685 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
11688 template<bool big_endian>
11689 class Target_selector_arm : public Target_selector
11692 Target_selector_arm()
11693 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
11694 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
11698 do_instantiate_target()
11699 { return new Target_arm<big_endian>(); }
11702 // Fix .ARM.exidx section coverage.
11704 template<bool big_endian>
11706 Target_arm<big_endian>::fix_exidx_coverage(
11708 const Input_objects* input_objects,
11709 Arm_output_section<big_endian>* exidx_section,
11710 Symbol_table* symtab)
11712 // We need to look at all the input sections in output in ascending
11713 // order of of output address. We do that by building a sorted list
11714 // of output sections by addresses. Then we looks at the output sections
11715 // in order. The input sections in an output section are already sorted
11716 // by addresses within the output section.
11718 typedef std::set<Output_section*, output_section_address_less_than>
11719 Sorted_output_section_list;
11720 Sorted_output_section_list sorted_output_sections;
11722 // Find out all the output sections of input sections pointed by
11723 // EXIDX input sections.
11724 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
11725 p != input_objects->relobj_end();
11728 Arm_relobj<big_endian>* arm_relobj =
11729 Arm_relobj<big_endian>::as_arm_relobj(*p);
11730 std::vector<unsigned int> shndx_list;
11731 arm_relobj->get_exidx_shndx_list(&shndx_list);
11732 for (size_t i = 0; i < shndx_list.size(); ++i)
11734 const Arm_exidx_input_section* exidx_input_section =
11735 arm_relobj->exidx_input_section_by_shndx(shndx_list[i]);
11736 gold_assert(exidx_input_section != NULL);
11737 if (!exidx_input_section->has_errors())
11739 unsigned int text_shndx = exidx_input_section->link();
11740 Output_section* os = arm_relobj->output_section(text_shndx);
11741 if (os != NULL && (os->flags() & elfcpp::SHF_ALLOC) != 0)
11742 sorted_output_sections.insert(os);
11747 // Go over the output sections in ascending order of output addresses.
11748 typedef typename Arm_output_section<big_endian>::Text_section_list
11750 Text_section_list sorted_text_sections;
11751 for(typename Sorted_output_section_list::iterator p =
11752 sorted_output_sections.begin();
11753 p != sorted_output_sections.end();
11756 Arm_output_section<big_endian>* arm_output_section =
11757 Arm_output_section<big_endian>::as_arm_output_section(*p);
11758 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
11761 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab,
11762 merge_exidx_entries());
11765 Target_selector_arm<false> target_selector_arm;
11766 Target_selector_arm<true> target_selector_armbe;
11768 } // End anonymous namespace.