1 // arm.cc -- arm target support for gold.
3 // Copyright 2009, 2010 Free Software Foundation, Inc.
4 // Written by Doug Kwan <dougkwan@google.com> based on the i386 code
5 // by Ian Lance Taylor <iant@google.com>.
6 // This file also contains borrowed and adapted code from
9 // This file is part of gold.
11 // This program is free software; you can redistribute it and/or modify
12 // it under the terms of the GNU General Public License as published by
13 // the Free Software Foundation; either version 3 of the License, or
14 // (at your option) any later version.
16 // This program is distributed in the hope that it will be useful,
17 // but WITHOUT ANY WARRANTY; without even the implied warranty of
18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 // GNU General Public License for more details.
21 // You should have received a copy of the GNU General Public License
22 // along with this program; if not, write to the Free Software
23 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
24 // MA 02110-1301, USA.
38 #include "parameters.h"
45 #include "copy-relocs.h"
47 #include "target-reloc.h"
48 #include "target-select.h"
52 #include "attributes.h"
53 #include "arm-reloc-property.h"
60 template<bool big_endian>
61 class Output_data_plt_arm;
63 template<bool big_endian>
66 template<bool big_endian>
67 class Arm_input_section;
69 class Arm_exidx_cantunwind;
71 class Arm_exidx_merged_section;
73 class Arm_exidx_fixup;
75 template<bool big_endian>
76 class Arm_output_section;
78 class Arm_exidx_input_section;
80 template<bool big_endian>
83 template<bool big_endian>
84 class Arm_relocate_functions;
86 template<bool big_endian>
87 class Arm_output_data_got;
89 template<bool big_endian>
93 typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address;
95 // Maximum branch offsets for ARM, THUMB and THUMB2.
96 const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8);
97 const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8);
98 const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4);
99 const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4);
100 const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
101 const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
103 // Thread Control Block size.
104 const size_t ARM_TCB_SIZE = 8;
106 // The arm target class.
108 // This is a very simple port of gold for ARM-EABI. It is intended for
109 // supporting Android only for the time being.
112 // - Implement all static relocation types documented in arm-reloc.def.
113 // - Make PLTs more flexible for different architecture features like
115 // There are probably a lot more.
117 // Ideally we would like to avoid using global variables but this is used
118 // very in many places and sometimes in loops. If we use a function
119 // returning a static instance of Arm_reloc_property_table, it will very
120 // slow in an threaded environment since the static instance needs to be
121 // locked. The pointer is below initialized in the
122 // Target::do_select_as_default_target() hook so that we do not spend time
123 // building the table if we are not linking ARM objects.
125 // An alternative is to to process the information in arm-reloc.def in
126 // compilation time and generate a representation of it in PODs only. That
127 // way we can avoid initialization when the linker starts.
129 Arm_reloc_property_table *arm_reloc_property_table = NULL;
131 // Instruction template class. This class is similar to the insn_sequence
132 // struct in bfd/elf32-arm.c.
137 // Types of instruction templates.
141 // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
142 // templates with class-specific semantics. Currently this is used
143 // only by the Cortex_a8_stub class for handling condition codes in
144 // conditional branches.
145 THUMB16_SPECIAL_TYPE,
151 // Factory methods to create instruction templates in different formats.
153 static const Insn_template
154 thumb16_insn(uint32_t data)
155 { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
157 // A Thumb conditional branch, in which the proper condition is inserted
158 // when we build the stub.
159 static const Insn_template
160 thumb16_bcond_insn(uint32_t data)
161 { return Insn_template(data, THUMB16_SPECIAL_TYPE, elfcpp::R_ARM_NONE, 1); }
163 static const Insn_template
164 thumb32_insn(uint32_t data)
165 { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); }
167 static const Insn_template
168 thumb32_b_insn(uint32_t data, int reloc_addend)
170 return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24,
174 static const Insn_template
175 arm_insn(uint32_t data)
176 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); }
178 static const Insn_template
179 arm_rel_insn(unsigned data, int reloc_addend)
180 { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); }
182 static const Insn_template
183 data_word(unsigned data, unsigned int r_type, int reloc_addend)
184 { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); }
186 // Accessors. This class is used for read-only objects so no modifiers
191 { return this->data_; }
193 // Return the instruction sequence type of this.
196 { return this->type_; }
198 // Return the ARM relocation type of this.
201 { return this->r_type_; }
205 { return this->reloc_addend_; }
207 // Return size of instruction template in bytes.
211 // Return byte-alignment of instruction template.
216 // We make the constructor private to ensure that only the factory
219 Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend)
220 : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend)
223 // Instruction specific data. This is used to store information like
224 // some of the instruction bits.
226 // Instruction template type.
228 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
229 unsigned int r_type_;
230 // Relocation addend.
231 int32_t reloc_addend_;
234 // Macro for generating code to stub types. One entry per long/short
238 DEF_STUB(long_branch_any_any) \
239 DEF_STUB(long_branch_v4t_arm_thumb) \
240 DEF_STUB(long_branch_thumb_only) \
241 DEF_STUB(long_branch_v4t_thumb_thumb) \
242 DEF_STUB(long_branch_v4t_thumb_arm) \
243 DEF_STUB(short_branch_v4t_thumb_arm) \
244 DEF_STUB(long_branch_any_arm_pic) \
245 DEF_STUB(long_branch_any_thumb_pic) \
246 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
247 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
248 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
249 DEF_STUB(long_branch_thumb_only_pic) \
250 DEF_STUB(a8_veneer_b_cond) \
251 DEF_STUB(a8_veneer_b) \
252 DEF_STUB(a8_veneer_bl) \
253 DEF_STUB(a8_veneer_blx) \
254 DEF_STUB(v4_veneer_bx)
258 #define DEF_STUB(x) arm_stub_##x,
264 // First reloc stub type.
265 arm_stub_reloc_first = arm_stub_long_branch_any_any,
266 // Last reloc stub type.
267 arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic,
269 // First Cortex-A8 stub type.
270 arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond,
271 // Last Cortex-A8 stub type.
272 arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
275 arm_stub_type_last = arm_stub_v4_veneer_bx
279 // Stub template class. Templates are meant to be read-only objects.
280 // A stub template for a stub type contains all read-only attributes
281 // common to all stubs of the same type.
286 Stub_template(Stub_type, const Insn_template*, size_t);
294 { return this->type_; }
296 // Return an array of instruction templates.
299 { return this->insns_; }
301 // Return size of template in number of instructions.
304 { return this->insn_count_; }
306 // Return size of template in bytes.
309 { return this->size_; }
311 // Return alignment of the stub template.
314 { return this->alignment_; }
316 // Return whether entry point is in thumb mode.
318 entry_in_thumb_mode() const
319 { return this->entry_in_thumb_mode_; }
321 // Return number of relocations in this template.
324 { return this->relocs_.size(); }
326 // Return index of the I-th instruction with relocation.
328 reloc_insn_index(size_t i) const
330 gold_assert(i < this->relocs_.size());
331 return this->relocs_[i].first;
334 // Return the offset of the I-th instruction with relocation from the
335 // beginning of the stub.
337 reloc_offset(size_t i) const
339 gold_assert(i < this->relocs_.size());
340 return this->relocs_[i].second;
344 // This contains information about an instruction template with a relocation
345 // and its offset from start of stub.
346 typedef std::pair<size_t, section_size_type> Reloc;
348 // A Stub_template may not be copied. We want to share templates as much
350 Stub_template(const Stub_template&);
351 Stub_template& operator=(const Stub_template&);
355 // Points to an array of Insn_templates.
356 const Insn_template* insns_;
357 // Number of Insn_templates in insns_[].
359 // Size of templated instructions in bytes.
361 // Alignment of templated instructions.
363 // Flag to indicate if entry is in thumb mode.
364 bool entry_in_thumb_mode_;
365 // A table of reloc instruction indices and offsets. We can find these by
366 // looking at the instruction templates but we pre-compute and then stash
367 // them here for speed.
368 std::vector<Reloc> relocs_;
372 // A class for code stubs. This is a base class for different type of
373 // stubs used in the ARM target.
379 static const section_offset_type invalid_offset =
380 static_cast<section_offset_type>(-1);
383 Stub(const Stub_template* stub_template)
384 : stub_template_(stub_template), offset_(invalid_offset)
391 // Return the stub template.
393 stub_template() const
394 { return this->stub_template_; }
396 // Return offset of code stub from beginning of its containing stub table.
400 gold_assert(this->offset_ != invalid_offset);
401 return this->offset_;
404 // Set offset of code stub from beginning of its containing stub table.
406 set_offset(section_offset_type offset)
407 { this->offset_ = offset; }
409 // Return the relocation target address of the i-th relocation in the
410 // stub. This must be defined in a child class.
412 reloc_target(size_t i)
413 { return this->do_reloc_target(i); }
415 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
417 write(unsigned char* view, section_size_type view_size, bool big_endian)
418 { this->do_write(view, view_size, big_endian); }
420 // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
421 // for the i-th instruction.
423 thumb16_special(size_t i)
424 { return this->do_thumb16_special(i); }
427 // This must be defined in the child class.
429 do_reloc_target(size_t) = 0;
431 // This may be overridden in the child class.
433 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
436 this->do_fixed_endian_write<true>(view, view_size);
438 this->do_fixed_endian_write<false>(view, view_size);
441 // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
442 // instruction template.
444 do_thumb16_special(size_t)
445 { gold_unreachable(); }
448 // A template to implement do_write.
449 template<bool big_endian>
451 do_fixed_endian_write(unsigned char*, section_size_type);
454 const Stub_template* stub_template_;
455 // Offset within the section of containing this stub.
456 section_offset_type offset_;
459 // Reloc stub class. These are stubs we use to fix up relocation because
460 // of limited branch ranges.
462 class Reloc_stub : public Stub
465 static const unsigned int invalid_index = static_cast<unsigned int>(-1);
466 // We assume we never jump to this address.
467 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
469 // Return destination address.
471 destination_address() const
473 gold_assert(this->destination_address_ != this->invalid_address);
474 return this->destination_address_;
477 // Set destination address.
479 set_destination_address(Arm_address address)
481 gold_assert(address != this->invalid_address);
482 this->destination_address_ = address;
485 // Reset destination address.
487 reset_destination_address()
488 { this->destination_address_ = this->invalid_address; }
490 // Determine stub type for a branch of a relocation of R_TYPE going
491 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
492 // the branch target is a thumb instruction. TARGET is used for look
493 // up ARM-specific linker settings.
495 stub_type_for_reloc(unsigned int r_type, Arm_address branch_address,
496 Arm_address branch_target, bool target_is_thumb);
498 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
499 // and an addend. Since we treat global and local symbol differently, we
500 // use a Symbol object for a global symbol and a object-index pair for
505 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
506 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
507 // and R_SYM must not be invalid_index.
508 Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj,
509 unsigned int r_sym, int32_t addend)
510 : stub_type_(stub_type), addend_(addend)
514 this->r_sym_ = Reloc_stub::invalid_index;
515 this->u_.symbol = symbol;
519 gold_assert(relobj != NULL && r_sym != invalid_index);
520 this->r_sym_ = r_sym;
521 this->u_.relobj = relobj;
528 // Accessors: Keys are meant to be read-only object so no modifiers are
534 { return this->stub_type_; }
536 // Return the local symbol index or invalid_index.
539 { return this->r_sym_; }
541 // Return the symbol if there is one.
544 { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
546 // Return the relobj if there is one.
549 { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
551 // Whether this equals to another key k.
553 eq(const Key& k) const
555 return ((this->stub_type_ == k.stub_type_)
556 && (this->r_sym_ == k.r_sym_)
557 && ((this->r_sym_ != Reloc_stub::invalid_index)
558 ? (this->u_.relobj == k.u_.relobj)
559 : (this->u_.symbol == k.u_.symbol))
560 && (this->addend_ == k.addend_));
563 // Return a hash value.
567 return (this->stub_type_
569 ^ gold::string_hash<char>(
570 (this->r_sym_ != Reloc_stub::invalid_index)
571 ? this->u_.relobj->name().c_str()
572 : this->u_.symbol->name())
576 // Functors for STL associative containers.
580 operator()(const Key& k) const
581 { return k.hash_value(); }
587 operator()(const Key& k1, const Key& k2) const
588 { return k1.eq(k2); }
591 // Name of key. This is mainly for debugging.
597 Stub_type stub_type_;
598 // If this is a local symbol, this is the index in the defining object.
599 // Otherwise, it is invalid_index for a global symbol.
601 // If r_sym_ is invalid index. This points to a global symbol.
602 // Otherwise, this points a relobj. We used the unsized and target
603 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
604 // Arm_relobj. This is done to avoid making the stub class a template
605 // as most of the stub machinery is endianity-neutral. However, it
606 // may require a bit of casting done by users of this class.
609 const Symbol* symbol;
610 const Relobj* relobj;
612 // Addend associated with a reloc.
617 // Reloc_stubs are created via a stub factory. So these are protected.
618 Reloc_stub(const Stub_template* stub_template)
619 : Stub(stub_template), destination_address_(invalid_address)
625 friend class Stub_factory;
627 // Return the relocation target address of the i-th relocation in the
630 do_reloc_target(size_t i)
632 // All reloc stub have only one relocation.
634 return this->destination_address_;
638 // Address of destination.
639 Arm_address destination_address_;
642 // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
643 // THUMB branch that meets the following conditions:
645 // 1. The branch straddles across a page boundary. i.e. lower 12-bit of
646 // branch address is 0xffe.
647 // 2. The branch target address is in the same page as the first word of the
649 // 3. The branch follows a 32-bit instruction which is not a branch.
651 // To do the fix up, we need to store the address of the branch instruction
652 // and its target at least. We also need to store the original branch
653 // instruction bits for the condition code in a conditional branch. The
654 // condition code is used in a special instruction template. We also want
655 // to identify input sections needing Cortex-A8 workaround quickly. We store
656 // extra information about object and section index of the code section
657 // containing a branch being fixed up. The information is used to mark
658 // the code section when we finalize the Cortex-A8 stubs.
661 class Cortex_a8_stub : public Stub
667 // Return the object of the code section containing the branch being fixed
671 { return this->relobj_; }
673 // Return the section index of the code section containing the branch being
677 { return this->shndx_; }
679 // Return the source address of stub. This is the address of the original
680 // branch instruction. LSB is 1 always set to indicate that it is a THUMB
683 source_address() const
684 { return this->source_address_; }
686 // Return the destination address of the stub. This is the branch taken
687 // address of the original branch instruction. LSB is 1 if it is a THUMB
688 // instruction address.
690 destination_address() const
691 { return this->destination_address_; }
693 // Return the instruction being fixed up.
695 original_insn() const
696 { return this->original_insn_; }
699 // Cortex_a8_stubs are created via a stub factory. So these are protected.
700 Cortex_a8_stub(const Stub_template* stub_template, Relobj* relobj,
701 unsigned int shndx, Arm_address source_address,
702 Arm_address destination_address, uint32_t original_insn)
703 : Stub(stub_template), relobj_(relobj), shndx_(shndx),
704 source_address_(source_address | 1U),
705 destination_address_(destination_address),
706 original_insn_(original_insn)
709 friend class Stub_factory;
711 // Return the relocation target address of the i-th relocation in the
714 do_reloc_target(size_t i)
716 if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond)
718 // The conditional branch veneer has two relocations.
720 return i == 0 ? this->source_address_ + 4 : this->destination_address_;
724 // All other Cortex-A8 stubs have only one relocation.
726 return this->destination_address_;
730 // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
732 do_thumb16_special(size_t);
735 // Object of the code section containing the branch being fixed up.
737 // Section index of the code section containing the branch begin fixed up.
739 // Source address of original branch.
740 Arm_address source_address_;
741 // Destination address of the original branch.
742 Arm_address destination_address_;
743 // Original branch instruction. This is needed for copying the condition
744 // code from a condition branch to its stub.
745 uint32_t original_insn_;
748 // ARMv4 BX Rx branch relocation stub class.
749 class Arm_v4bx_stub : public Stub
755 // Return the associated register.
758 { return this->reg_; }
761 // Arm V4BX stubs are created via a stub factory. So these are protected.
762 Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg)
763 : Stub(stub_template), reg_(reg)
766 friend class Stub_factory;
768 // Return the relocation target address of the i-th relocation in the
771 do_reloc_target(size_t)
772 { gold_unreachable(); }
774 // This may be overridden in the child class.
776 do_write(unsigned char* view, section_size_type view_size, bool big_endian)
779 this->do_fixed_endian_v4bx_write<true>(view, view_size);
781 this->do_fixed_endian_v4bx_write<false>(view, view_size);
785 // A template to implement do_write.
786 template<bool big_endian>
788 do_fixed_endian_v4bx_write(unsigned char* view, section_size_type)
790 const Insn_template* insns = this->stub_template()->insns();
791 elfcpp::Swap<32, big_endian>::writeval(view,
793 + (this->reg_ << 16)));
794 view += insns[0].size();
795 elfcpp::Swap<32, big_endian>::writeval(view,
796 (insns[1].data() + this->reg_));
797 view += insns[1].size();
798 elfcpp::Swap<32, big_endian>::writeval(view,
799 (insns[2].data() + this->reg_));
802 // A register index (r0-r14), which is associated with the stub.
806 // Stub factory class.
811 // Return the unique instance of this class.
812 static const Stub_factory&
815 static Stub_factory singleton;
819 // Make a relocation stub.
821 make_reloc_stub(Stub_type stub_type) const
823 gold_assert(stub_type >= arm_stub_reloc_first
824 && stub_type <= arm_stub_reloc_last);
825 return new Reloc_stub(this->stub_templates_[stub_type]);
828 // Make a Cortex-A8 stub.
830 make_cortex_a8_stub(Stub_type stub_type, Relobj* relobj, unsigned int shndx,
831 Arm_address source, Arm_address destination,
832 uint32_t original_insn) const
834 gold_assert(stub_type >= arm_stub_cortex_a8_first
835 && stub_type <= arm_stub_cortex_a8_last);
836 return new Cortex_a8_stub(this->stub_templates_[stub_type], relobj, shndx,
837 source, destination, original_insn);
840 // Make an ARM V4BX relocation stub.
841 // This method creates a stub from the arm_stub_v4_veneer_bx template only.
843 make_arm_v4bx_stub(uint32_t reg) const
845 gold_assert(reg < 0xf);
846 return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx],
851 // Constructor and destructor are protected since we only return a single
852 // instance created in Stub_factory::get_instance().
856 // A Stub_factory may not be copied since it is a singleton.
857 Stub_factory(const Stub_factory&);
858 Stub_factory& operator=(Stub_factory&);
860 // Stub templates. These are initialized in the constructor.
861 const Stub_template* stub_templates_[arm_stub_type_last+1];
864 // A class to hold stubs for the ARM target.
866 template<bool big_endian>
867 class Stub_table : public Output_data
870 Stub_table(Arm_input_section<big_endian>* owner)
871 : Output_data(), owner_(owner), reloc_stubs_(), cortex_a8_stubs_(),
872 arm_v4bx_stubs_(0xf), prev_data_size_(0), prev_addralign_(1)
878 // Owner of this stub table.
879 Arm_input_section<big_endian>*
881 { return this->owner_; }
883 // Whether this stub table is empty.
887 return (this->reloc_stubs_.empty()
888 && this->cortex_a8_stubs_.empty()
889 && this->arm_v4bx_stubs_.empty());
892 // Return the current data size.
894 current_data_size() const
895 { return this->current_data_size_for_child(); }
897 // Add a STUB with using KEY. Caller is reponsible for avoid adding
898 // if already a STUB with the same key has been added.
900 add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key)
902 const Stub_template* stub_template = stub->stub_template();
903 gold_assert(stub_template->type() == key.stub_type());
904 this->reloc_stubs_[key] = stub;
907 // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
908 // Caller is reponsible for avoid adding if already a STUB with the same
909 // address has been added.
911 add_cortex_a8_stub(Arm_address address, Cortex_a8_stub* stub)
913 std::pair<Arm_address, Cortex_a8_stub*> value(address, stub);
914 this->cortex_a8_stubs_.insert(value);
917 // Add an ARM V4BX relocation stub. A register index will be retrieved
920 add_arm_v4bx_stub(Arm_v4bx_stub* stub)
922 gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL);
923 this->arm_v4bx_stubs_[stub->reg()] = stub;
926 // Remove all Cortex-A8 stubs.
928 remove_all_cortex_a8_stubs();
930 // Look up a relocation stub using KEY. Return NULL if there is none.
932 find_reloc_stub(const Reloc_stub::Key& key) const
934 typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
935 return (p != this->reloc_stubs_.end()) ? p->second : NULL;
938 // Look up an arm v4bx relocation stub using the register index.
939 // Return NULL if there is none.
941 find_arm_v4bx_stub(const uint32_t reg) const
943 gold_assert(reg < 0xf);
944 return this->arm_v4bx_stubs_[reg];
947 // Relocate stubs in this stub table.
949 relocate_stubs(const Relocate_info<32, big_endian>*,
950 Target_arm<big_endian>*, Output_section*,
951 unsigned char*, Arm_address, section_size_type);
953 // Update data size and alignment at the end of a relaxation pass. Return
954 // true if either data size or alignment is different from that of the
955 // previous relaxation pass.
957 update_data_size_and_addralign();
959 // Finalize stubs. Set the offsets of all stubs and mark input sections
960 // needing the Cortex-A8 workaround.
964 // Apply Cortex-A8 workaround to an address range.
966 apply_cortex_a8_workaround_to_address_range(Target_arm<big_endian>*,
967 unsigned char*, Arm_address,
971 // Write out section contents.
973 do_write(Output_file*);
975 // Return the required alignment.
978 { return this->prev_addralign_; }
980 // Reset address and file offset.
982 do_reset_address_and_file_offset()
983 { this->set_current_data_size_for_child(this->prev_data_size_); }
985 // Set final data size.
987 set_final_data_size()
988 { this->set_data_size(this->current_data_size()); }
991 // Relocate one stub.
993 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
994 Target_arm<big_endian>*, Output_section*,
995 unsigned char*, Arm_address, section_size_type);
997 // Unordered map of relocation stubs.
999 Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
1000 Reloc_stub::Key::equal_to>
1003 // List of Cortex-A8 stubs ordered by addresses of branches being
1004 // fixed up in output.
1005 typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list;
1006 // List of Arm V4BX relocation stubs ordered by associated registers.
1007 typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list;
1009 // Owner of this stub table.
1010 Arm_input_section<big_endian>* owner_;
1011 // The relocation stubs.
1012 Reloc_stub_map reloc_stubs_;
1013 // The cortex_a8_stubs.
1014 Cortex_a8_stub_list cortex_a8_stubs_;
1015 // The Arm V4BX relocation stubs.
1016 Arm_v4bx_stub_list arm_v4bx_stubs_;
1017 // data size of this in the previous pass.
1018 off_t prev_data_size_;
1019 // address alignment of this in the previous pass.
1020 uint64_t prev_addralign_;
1023 // Arm_exidx_cantunwind class. This represents an EXIDX_CANTUNWIND entry
1024 // we add to the end of an EXIDX input section that goes into the output.
1026 class Arm_exidx_cantunwind : public Output_section_data
1029 Arm_exidx_cantunwind(Relobj* relobj, unsigned int shndx)
1030 : Output_section_data(8, 4, true), relobj_(relobj), shndx_(shndx)
1033 // Return the object containing the section pointed by this.
1036 { return this->relobj_; }
1038 // Return the section index of the section pointed by this.
1041 { return this->shndx_; }
1045 do_write(Output_file* of)
1047 if (parameters->target().is_big_endian())
1048 this->do_fixed_endian_write<true>(of);
1050 this->do_fixed_endian_write<false>(of);
1054 // Implement do_write for a given endianity.
1055 template<bool big_endian>
1057 do_fixed_endian_write(Output_file*);
1059 // The object containing the section pointed by this.
1061 // The section index of the section pointed by this.
1062 unsigned int shndx_;
1065 // During EXIDX coverage fix-up, we compact an EXIDX section. The
1066 // Offset map is used to map input section offset within the EXIDX section
1067 // to the output offset from the start of this EXIDX section.
1069 typedef std::map<section_offset_type, section_offset_type>
1070 Arm_exidx_section_offset_map;
1072 // Arm_exidx_merged_section class. This represents an EXIDX input section
1073 // with some of its entries merged.
1075 class Arm_exidx_merged_section : public Output_relaxed_input_section
1078 // Constructor for Arm_exidx_merged_section.
1079 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
1080 // SECTION_OFFSET_MAP points to a section offset map describing how
1081 // parts of the input section are mapped to output. DELETED_BYTES is
1082 // the number of bytes deleted from the EXIDX input section.
1083 Arm_exidx_merged_section(
1084 const Arm_exidx_input_section& exidx_input_section,
1085 const Arm_exidx_section_offset_map& section_offset_map,
1086 uint32_t deleted_bytes);
1088 // Return the original EXIDX input section.
1089 const Arm_exidx_input_section&
1090 exidx_input_section() const
1091 { return this->exidx_input_section_; }
1093 // Return the section offset map.
1094 const Arm_exidx_section_offset_map&
1095 section_offset_map() const
1096 { return this->section_offset_map_; }
1099 // Write merged section into file OF.
1101 do_write(Output_file* of);
1104 do_output_offset(const Relobj*, unsigned int, section_offset_type,
1105 section_offset_type*) const;
1108 // Original EXIDX input section.
1109 const Arm_exidx_input_section& exidx_input_section_;
1110 // Section offset map.
1111 const Arm_exidx_section_offset_map& section_offset_map_;
1114 // A class to wrap an ordinary input section containing executable code.
1116 template<bool big_endian>
1117 class Arm_input_section : public Output_relaxed_input_section
1120 Arm_input_section(Relobj* relobj, unsigned int shndx)
1121 : Output_relaxed_input_section(relobj, shndx, 1),
1122 original_addralign_(1), original_size_(0), stub_table_(NULL)
1125 ~Arm_input_section()
1132 // Whether this is a stub table owner.
1134 is_stub_table_owner() const
1135 { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
1137 // Return the stub table.
1138 Stub_table<big_endian>*
1140 { return this->stub_table_; }
1142 // Set the stub_table.
1144 set_stub_table(Stub_table<big_endian>* stub_table)
1145 { this->stub_table_ = stub_table; }
1147 // Downcast a base pointer to an Arm_input_section pointer. This is
1148 // not type-safe but we only use Arm_input_section not the base class.
1149 static Arm_input_section<big_endian>*
1150 as_arm_input_section(Output_relaxed_input_section* poris)
1151 { return static_cast<Arm_input_section<big_endian>*>(poris); }
1154 // Write data to output file.
1156 do_write(Output_file*);
1158 // Return required alignment of this.
1160 do_addralign() const
1162 if (this->is_stub_table_owner())
1163 return std::max(this->stub_table_->addralign(),
1164 this->original_addralign_);
1166 return this->original_addralign_;
1169 // Finalize data size.
1171 set_final_data_size();
1173 // Reset address and file offset.
1175 do_reset_address_and_file_offset();
1179 do_output_offset(const Relobj* object, unsigned int shndx,
1180 section_offset_type offset,
1181 section_offset_type* poutput) const
1183 if ((object == this->relobj())
1184 && (shndx == this->shndx())
1186 && (convert_types<uint64_t, section_offset_type>(offset)
1187 <= this->original_size_))
1197 // Copying is not allowed.
1198 Arm_input_section(const Arm_input_section&);
1199 Arm_input_section& operator=(const Arm_input_section&);
1201 // Address alignment of the original input section.
1202 uint64_t original_addralign_;
1203 // Section size of the original input section.
1204 uint64_t original_size_;
1206 Stub_table<big_endian>* stub_table_;
1209 // Arm_exidx_fixup class. This is used to define a number of methods
1210 // and keep states for fixing up EXIDX coverage.
1212 class Arm_exidx_fixup
1215 Arm_exidx_fixup(Output_section* exidx_output_section)
1216 : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
1217 last_inlined_entry_(0), last_input_section_(NULL),
1218 section_offset_map_(NULL), first_output_text_section_(NULL)
1222 { delete this->section_offset_map_; }
1224 // Process an EXIDX section for entry merging. Return number of bytes to
1225 // be deleted in output. If parts of the input EXIDX section are merged
1226 // a heap allocated Arm_exidx_section_offset_map is store in the located
1227 // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
1229 template<bool big_endian>
1231 process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
1232 Arm_exidx_section_offset_map** psection_offset_map);
1234 // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
1235 // input section, if there is not one already.
1237 add_exidx_cantunwind_as_needed();
1239 // Return the output section for the text section which is linked to the
1240 // first exidx input in output.
1242 first_output_text_section() const
1243 { return this->first_output_text_section_; }
1246 // Copying is not allowed.
1247 Arm_exidx_fixup(const Arm_exidx_fixup&);
1248 Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
1250 // Type of EXIDX unwind entry.
1255 // EXIDX_CANTUNWIND.
1256 UT_EXIDX_CANTUNWIND,
1263 // Process an EXIDX entry. We only care about the second word of the
1264 // entry. Return true if the entry can be deleted.
1266 process_exidx_entry(uint32_t second_word);
1268 // Update the current section offset map during EXIDX section fix-up.
1269 // If there is no map, create one. INPUT_OFFSET is the offset of a
1270 // reference point, DELETED_BYTES is the number of deleted by in the
1271 // section so far. If DELETE_ENTRY is true, the reference point and
1272 // all offsets after the previous reference point are discarded.
1274 update_offset_map(section_offset_type input_offset,
1275 section_size_type deleted_bytes, bool delete_entry);
1277 // EXIDX output section.
1278 Output_section* exidx_output_section_;
1279 // Unwind type of the last EXIDX entry processed.
1280 Unwind_type last_unwind_type_;
1281 // Last seen inlined EXIDX entry.
1282 uint32_t last_inlined_entry_;
1283 // Last processed EXIDX input section.
1284 const Arm_exidx_input_section* last_input_section_;
1285 // Section offset map created in process_exidx_section.
1286 Arm_exidx_section_offset_map* section_offset_map_;
1287 // Output section for the text section which is linked to the first exidx
1289 Output_section* first_output_text_section_;
1292 // Arm output section class. This is defined mainly to add a number of
1293 // stub generation methods.
1295 template<bool big_endian>
1296 class Arm_output_section : public Output_section
1299 typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
1301 Arm_output_section(const char* name, elfcpp::Elf_Word type,
1302 elfcpp::Elf_Xword flags)
1303 : Output_section(name, type, flags)
1306 ~Arm_output_section()
1309 // Group input sections for stub generation.
1311 group_sections(section_size_type, bool, Target_arm<big_endian>*);
1313 // Downcast a base pointer to an Arm_output_section pointer. This is
1314 // not type-safe but we only use Arm_output_section not the base class.
1315 static Arm_output_section<big_endian>*
1316 as_arm_output_section(Output_section* os)
1317 { return static_cast<Arm_output_section<big_endian>*>(os); }
1319 // Append all input text sections in this into LIST.
1321 append_text_sections_to_list(Text_section_list* list);
1323 // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
1324 // is a list of text input sections sorted in ascending order of their
1325 // output addresses.
1327 fix_exidx_coverage(Layout* layout,
1328 const Text_section_list& sorted_text_section,
1329 Symbol_table* symtab);
1333 typedef Output_section::Input_section Input_section;
1334 typedef Output_section::Input_section_list Input_section_list;
1336 // Create a stub group.
1337 void create_stub_group(Input_section_list::const_iterator,
1338 Input_section_list::const_iterator,
1339 Input_section_list::const_iterator,
1340 Target_arm<big_endian>*,
1341 std::vector<Output_relaxed_input_section*>*);
1344 // Arm_exidx_input_section class. This represents an EXIDX input section.
1346 class Arm_exidx_input_section
1349 static const section_offset_type invalid_offset =
1350 static_cast<section_offset_type>(-1);
1352 Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
1353 unsigned int link, uint32_t size, uint32_t addralign)
1354 : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
1355 addralign_(addralign)
1358 ~Arm_exidx_input_section()
1361 // Accessors: This is a read-only class.
1363 // Return the object containing this EXIDX input section.
1366 { return this->relobj_; }
1368 // Return the section index of this EXIDX input section.
1371 { return this->shndx_; }
1373 // Return the section index of linked text section in the same object.
1376 { return this->link_; }
1378 // Return size of the EXIDX input section.
1381 { return this->size_; }
1383 // Reutnr address alignment of EXIDX input section.
1386 { return this->addralign_; }
1389 // Object containing this.
1391 // Section index of this.
1392 unsigned int shndx_;
1393 // text section linked to this in the same object.
1395 // Size of this. For ARM 32-bit is sufficient.
1397 // Address alignment of this. For ARM 32-bit is sufficient.
1398 uint32_t addralign_;
1401 // Arm_relobj class.
1403 template<bool big_endian>
1404 class Arm_relobj : public Sized_relobj<32, big_endian>
1407 static const Arm_address invalid_address = static_cast<Arm_address>(-1);
1409 Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
1410 const typename elfcpp::Ehdr<32, big_endian>& ehdr)
1411 : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
1412 stub_tables_(), local_symbol_is_thumb_function_(),
1413 attributes_section_data_(NULL), mapping_symbols_info_(),
1414 section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
1415 output_local_symbol_count_needs_update_(false)
1419 { delete this->attributes_section_data_; }
1421 // Return the stub table of the SHNDX-th section if there is one.
1422 Stub_table<big_endian>*
1423 stub_table(unsigned int shndx) const
1425 gold_assert(shndx < this->stub_tables_.size());
1426 return this->stub_tables_[shndx];
1429 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1431 set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
1433 gold_assert(shndx < this->stub_tables_.size());
1434 this->stub_tables_[shndx] = stub_table;
1437 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1438 // index. This is only valid after do_count_local_symbol is called.
1440 local_symbol_is_thumb_function(unsigned int r_sym) const
1442 gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
1443 return this->local_symbol_is_thumb_function_[r_sym];
1446 // Scan all relocation sections for stub generation.
1448 scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
1451 // Convert regular input section with index SHNDX to a relaxed section.
1453 convert_input_section_to_relaxed_section(unsigned shndx)
1455 // The stubs have relocations and we need to process them after writing
1456 // out the stubs. So relocation now must follow section write.
1457 this->set_section_offset(shndx, -1ULL);
1458 this->set_relocs_must_follow_section_writes();
1461 // Downcast a base pointer to an Arm_relobj pointer. This is
1462 // not type-safe but we only use Arm_relobj not the base class.
1463 static Arm_relobj<big_endian>*
1464 as_arm_relobj(Relobj* relobj)
1465 { return static_cast<Arm_relobj<big_endian>*>(relobj); }
1467 // Processor-specific flags in ELF file header. This is valid only after
1470 processor_specific_flags() const
1471 { return this->processor_specific_flags_; }
1473 // Attribute section data This is the contents of the .ARM.attribute section
1475 const Attributes_section_data*
1476 attributes_section_data() const
1477 { return this->attributes_section_data_; }
1479 // Mapping symbol location.
1480 typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
1482 // Functor for STL container.
1483 struct Mapping_symbol_position_less
1486 operator()(const Mapping_symbol_position& p1,
1487 const Mapping_symbol_position& p2) const
1489 return (p1.first < p2.first
1490 || (p1.first == p2.first && p1.second < p2.second));
1494 // We only care about the first character of a mapping symbol, so
1495 // we only store that instead of the whole symbol name.
1496 typedef std::map<Mapping_symbol_position, char,
1497 Mapping_symbol_position_less> Mapping_symbols_info;
1499 // Whether a section contains any Cortex-A8 workaround.
1501 section_has_cortex_a8_workaround(unsigned int shndx) const
1503 return (this->section_has_cortex_a8_workaround_ != NULL
1504 && (*this->section_has_cortex_a8_workaround_)[shndx]);
1507 // Mark a section that has Cortex-A8 workaround.
1509 mark_section_for_cortex_a8_workaround(unsigned int shndx)
1511 if (this->section_has_cortex_a8_workaround_ == NULL)
1512 this->section_has_cortex_a8_workaround_ =
1513 new std::vector<bool>(this->shnum(), false);
1514 (*this->section_has_cortex_a8_workaround_)[shndx] = true;
1517 // Return the EXIDX section of an text section with index SHNDX or NULL
1518 // if the text section has no associated EXIDX section.
1519 const Arm_exidx_input_section*
1520 exidx_input_section_by_link(unsigned int shndx) const
1522 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1523 return ((p != this->exidx_section_map_.end()
1524 && p->second->link() == shndx)
1529 // Return the EXIDX section with index SHNDX or NULL if there is none.
1530 const Arm_exidx_input_section*
1531 exidx_input_section_by_shndx(unsigned shndx) const
1533 Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
1534 return ((p != this->exidx_section_map_.end()
1535 && p->second->shndx() == shndx)
1540 // Whether output local symbol count needs updating.
1542 output_local_symbol_count_needs_update() const
1543 { return this->output_local_symbol_count_needs_update_; }
1545 // Set output_local_symbol_count_needs_update flag to be true.
1547 set_output_local_symbol_count_needs_update()
1548 { this->output_local_symbol_count_needs_update_ = true; }
1550 // Update output local symbol count at the end of relaxation.
1552 update_output_local_symbol_count();
1555 // Post constructor setup.
1559 // Call parent's setup method.
1560 Sized_relobj<32, big_endian>::do_setup();
1562 // Initialize look-up tables.
1563 Stub_table_list empty_stub_table_list(this->shnum(), NULL);
1564 this->stub_tables_.swap(empty_stub_table_list);
1567 // Count the local symbols.
1569 do_count_local_symbols(Stringpool_template<char>*,
1570 Stringpool_template<char>*);
1573 do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
1574 const unsigned char* pshdrs,
1575 typename Sized_relobj<32, big_endian>::Views* pivews);
1577 // Read the symbol information.
1579 do_read_symbols(Read_symbols_data* sd);
1581 // Process relocs for garbage collection.
1583 do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
1587 // Whether a section needs to be scanned for relocation stubs.
1589 section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1590 const Relobj::Output_sections&,
1591 const Symbol_table *, const unsigned char*);
1593 // Whether a section is a scannable text section.
1595 section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
1596 const Output_section*, const Symbol_table *);
1598 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1600 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
1601 unsigned int, Output_section*,
1602 const Symbol_table *);
1604 // Scan a section for the Cortex-A8 erratum.
1606 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
1607 unsigned int, Output_section*,
1608 Target_arm<big_endian>*);
1610 // Find the linked text section of an EXIDX section by looking at the
1611 // first reloction of the EXIDX section. PSHDR points to the section
1612 // headers of a relocation section and PSYMS points to the local symbols.
1613 // PSHNDX points to a location storing the text section index if found.
1614 // Return whether we can find the linked section.
1616 find_linked_text_section(const unsigned char* pshdr,
1617 const unsigned char* psyms, unsigned int* pshndx);
1620 // Make a new Arm_exidx_input_section object for EXIDX section with
1621 // index SHNDX and section header SHDR. TEXT_SHNDX is the section
1622 // index of the linked text section.
1624 make_exidx_input_section(unsigned int shndx,
1625 const elfcpp::Shdr<32, big_endian>& shdr,
1626 unsigned int text_shndx);
1628 // Return the output address of either a plain input section or a
1629 // relaxed input section. SHNDX is the section index.
1631 simple_input_section_output_address(unsigned int, Output_section*);
1633 typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
1634 typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
1637 // List of stub tables.
1638 Stub_table_list stub_tables_;
1639 // Bit vector to tell if a local symbol is a thumb function or not.
1640 // This is only valid after do_count_local_symbol is called.
1641 std::vector<bool> local_symbol_is_thumb_function_;
1642 // processor-specific flags in ELF file header.
1643 elfcpp::Elf_Word processor_specific_flags_;
1644 // Object attributes if there is an .ARM.attributes section or NULL.
1645 Attributes_section_data* attributes_section_data_;
1646 // Mapping symbols information.
1647 Mapping_symbols_info mapping_symbols_info_;
1648 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1649 std::vector<bool>* section_has_cortex_a8_workaround_;
1650 // Map a text section to its associated .ARM.exidx section, if there is one.
1651 Exidx_section_map exidx_section_map_;
1652 // Whether output local symbol count needs updating.
1653 bool output_local_symbol_count_needs_update_;
1656 // Arm_dynobj class.
1658 template<bool big_endian>
1659 class Arm_dynobj : public Sized_dynobj<32, big_endian>
1662 Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
1663 const elfcpp::Ehdr<32, big_endian>& ehdr)
1664 : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
1665 processor_specific_flags_(0), attributes_section_data_(NULL)
1669 { delete this->attributes_section_data_; }
1671 // Downcast a base pointer to an Arm_relobj pointer. This is
1672 // not type-safe but we only use Arm_relobj not the base class.
1673 static Arm_dynobj<big_endian>*
1674 as_arm_dynobj(Dynobj* dynobj)
1675 { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
1677 // Processor-specific flags in ELF file header. This is valid only after
1680 processor_specific_flags() const
1681 { return this->processor_specific_flags_; }
1683 // Attributes section data.
1684 const Attributes_section_data*
1685 attributes_section_data() const
1686 { return this->attributes_section_data_; }
1689 // Read the symbol information.
1691 do_read_symbols(Read_symbols_data* sd);
1694 // processor-specific flags in ELF file header.
1695 elfcpp::Elf_Word processor_specific_flags_;
1696 // Object attributes if there is an .ARM.attributes section or NULL.
1697 Attributes_section_data* attributes_section_data_;
1700 // Functor to read reloc addends during stub generation.
1702 template<int sh_type, bool big_endian>
1703 struct Stub_addend_reader
1705 // Return the addend for a relocation of a particular type. Depending
1706 // on whether this is a REL or RELA relocation, read the addend from a
1707 // view or from a Reloc object.
1708 elfcpp::Elf_types<32>::Elf_Swxword
1710 unsigned int /* r_type */,
1711 const unsigned char* /* view */,
1712 const typename Reloc_types<sh_type,
1713 32, big_endian>::Reloc& /* reloc */) const;
1716 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1718 template<bool big_endian>
1719 struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
1721 elfcpp::Elf_types<32>::Elf_Swxword
1724 const unsigned char*,
1725 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
1728 // Specialized Stub_addend_reader for RELA type relocation sections.
1729 // We currently do not handle RELA type relocation sections but it is trivial
1730 // to implement the addend reader. This is provided for completeness and to
1731 // make it easier to add support for RELA relocation sections in the future.
1733 template<bool big_endian>
1734 struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
1736 elfcpp::Elf_types<32>::Elf_Swxword
1739 const unsigned char*,
1740 const typename Reloc_types<elfcpp::SHT_RELA, 32,
1741 big_endian>::Reloc& reloc) const
1742 { return reloc.get_r_addend(); }
1745 // Cortex_a8_reloc class. We keep record of relocation that may need
1746 // the Cortex-A8 erratum workaround.
1748 class Cortex_a8_reloc
1751 Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
1752 Arm_address destination)
1753 : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
1759 // Accessors: This is a read-only class.
1761 // Return the relocation stub associated with this relocation if there is
1765 { return this->reloc_stub_; }
1767 // Return the relocation type.
1770 { return this->r_type_; }
1772 // Return the destination address of the relocation. LSB stores the THUMB
1776 { return this->destination_; }
1779 // Associated relocation stub if there is one, or NULL.
1780 const Reloc_stub* reloc_stub_;
1782 unsigned int r_type_;
1783 // Destination address of this relocation. LSB is used to distinguish
1785 Arm_address destination_;
1788 // Arm_output_data_got class. We derive this from Output_data_got to add
1789 // extra methods to handle TLS relocations in a static link.
1791 template<bool big_endian>
1792 class Arm_output_data_got : public Output_data_got<32, big_endian>
1795 Arm_output_data_got(Symbol_table* symtab, Layout* layout)
1796 : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
1799 // Add a static entry for the GOT entry at OFFSET. GSYM is a global
1800 // symbol and R_TYPE is the code of a dynamic relocation that needs to be
1801 // applied in a static link.
1803 add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1804 { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
1806 // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
1807 // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
1808 // relocation that needs to be applied in a static link.
1810 add_static_reloc(unsigned int got_offset, unsigned int r_type,
1811 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1813 this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
1817 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
1818 // The first one is initialized to be 1, which is the module index for
1819 // the main executable and the second one 0. A reloc of the type
1820 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
1821 // be applied by gold. GSYM is a global symbol.
1823 add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
1825 // Same as the above but for a local symbol in OBJECT with INDEX.
1827 add_tls_gd32_with_static_reloc(unsigned int got_type,
1828 Sized_relobj<32, big_endian>* object,
1829 unsigned int index);
1832 // Write out the GOT table.
1834 do_write(Output_file*);
1837 // This class represent dynamic relocations that need to be applied by
1838 // gold because we are using TLS relocations in a static link.
1842 Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
1843 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
1844 { this->u_.global.symbol = gsym; }
1846 Static_reloc(unsigned int got_offset, unsigned int r_type,
1847 Sized_relobj<32, big_endian>* relobj, unsigned int index)
1848 : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
1850 this->u_.local.relobj = relobj;
1851 this->u_.local.index = index;
1854 // Return the GOT offset.
1857 { return this->got_offset_; }
1862 { return this->r_type_; }
1864 // Whether the symbol is global or not.
1866 symbol_is_global() const
1867 { return this->symbol_is_global_; }
1869 // For a relocation against a global symbol, the global symbol.
1873 gold_assert(this->symbol_is_global_);
1874 return this->u_.global.symbol;
1877 // For a relocation against a local symbol, the defining object.
1878 Sized_relobj<32, big_endian>*
1881 gold_assert(!this->symbol_is_global_);
1882 return this->u_.local.relobj;
1885 // For a relocation against a local symbol, the local symbol index.
1889 gold_assert(!this->symbol_is_global_);
1890 return this->u_.local.index;
1894 // GOT offset of the entry to which this relocation is applied.
1895 unsigned int got_offset_;
1896 // Type of relocation.
1897 unsigned int r_type_;
1898 // Whether this relocation is against a global symbol.
1899 bool symbol_is_global_;
1900 // A global or local symbol.
1905 // For a global symbol, the symbol itself.
1910 // For a local symbol, the object defining object.
1911 Sized_relobj<32, big_endian>* relobj;
1912 // For a local symbol, the symbol index.
1918 // Symbol table of the output object.
1919 Symbol_table* symbol_table_;
1920 // Layout of the output object.
1922 // Static relocs to be applied to the GOT.
1923 std::vector<Static_reloc> static_relocs_;
1926 // Utilities for manipulating integers of up to 32-bits
1930 // Sign extend an n-bit unsigned integer stored in an uint32_t into
1931 // an int32_t. NO_BITS must be between 1 to 32.
1932 template<int no_bits>
1933 static inline int32_t
1934 sign_extend(uint32_t bits)
1936 gold_assert(no_bits >= 0 && no_bits <= 32);
1938 return static_cast<int32_t>(bits);
1939 uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
1941 uint32_t top_bit = 1U << (no_bits - 1);
1942 int32_t as_signed = static_cast<int32_t>(bits);
1943 return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
1946 // Detects overflow of an NO_BITS integer stored in a uint32_t.
1947 template<int no_bits>
1949 has_overflow(uint32_t bits)
1951 gold_assert(no_bits >= 0 && no_bits <= 32);
1954 int32_t max = (1 << (no_bits - 1)) - 1;
1955 int32_t min = -(1 << (no_bits - 1));
1956 int32_t as_signed = static_cast<int32_t>(bits);
1957 return as_signed > max || as_signed < min;
1960 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
1961 // fits in the given number of bits as either a signed or unsigned value.
1962 // For example, has_signed_unsigned_overflow<8> would check
1963 // -128 <= bits <= 255
1964 template<int no_bits>
1966 has_signed_unsigned_overflow(uint32_t bits)
1968 gold_assert(no_bits >= 2 && no_bits <= 32);
1971 int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
1972 int32_t min = -(1 << (no_bits - 1));
1973 int32_t as_signed = static_cast<int32_t>(bits);
1974 return as_signed > max || as_signed < min;
1977 // Select bits from A and B using bits in MASK. For each n in [0..31],
1978 // the n-th bit in the result is chosen from the n-th bits of A and B.
1979 // A zero selects A and a one selects B.
1980 static inline uint32_t
1981 bit_select(uint32_t a, uint32_t b, uint32_t mask)
1982 { return (a & ~mask) | (b & mask); }
1985 template<bool big_endian>
1986 class Target_arm : public Sized_target<32, big_endian>
1989 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
1992 // When were are relocating a stub, we pass this as the relocation number.
1993 static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
1996 : Sized_target<32, big_endian>(&arm_info),
1997 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
1998 copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
1999 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
2000 stub_tables_(), stub_factory_(Stub_factory::get_instance()),
2001 may_use_blx_(false), should_force_pic_veneer_(false),
2002 arm_input_section_map_(), attributes_section_data_(NULL),
2003 fix_cortex_a8_(false), cortex_a8_relocs_info_()
2006 // Whether we can use BLX.
2009 { return this->may_use_blx_; }
2011 // Set use-BLX flag.
2013 set_may_use_blx(bool value)
2014 { this->may_use_blx_ = value; }
2016 // Whether we force PCI branch veneers.
2018 should_force_pic_veneer() const
2019 { return this->should_force_pic_veneer_; }
2021 // Set PIC veneer flag.
2023 set_should_force_pic_veneer(bool value)
2024 { this->should_force_pic_veneer_ = value; }
2026 // Whether we use THUMB-2 instructions.
2028 using_thumb2() const
2030 Object_attribute* attr =
2031 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2032 int arch = attr->int_value();
2033 return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
2036 // Whether we use THUMB/THUMB-2 instructions only.
2038 using_thumb_only() const
2040 Object_attribute* attr =
2041 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2042 if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
2043 && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
2045 attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
2046 return attr->int_value() == 'M';
2049 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
2051 may_use_arm_nop() const
2053 Object_attribute* attr =
2054 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2055 int arch = attr->int_value();
2056 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2057 || arch == elfcpp::TAG_CPU_ARCH_V6K
2058 || arch == elfcpp::TAG_CPU_ARCH_V7
2059 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2062 // Whether we have THUMB-2 NOP.W instruction.
2064 may_use_thumb2_nop() const
2066 Object_attribute* attr =
2067 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
2068 int arch = attr->int_value();
2069 return (arch == elfcpp::TAG_CPU_ARCH_V6T2
2070 || arch == elfcpp::TAG_CPU_ARCH_V7
2071 || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
2074 // Process the relocations to determine unreferenced sections for
2075 // garbage collection.
2077 gc_process_relocs(Symbol_table* symtab,
2079 Sized_relobj<32, big_endian>* object,
2080 unsigned int data_shndx,
2081 unsigned int sh_type,
2082 const unsigned char* prelocs,
2084 Output_section* output_section,
2085 bool needs_special_offset_handling,
2086 size_t local_symbol_count,
2087 const unsigned char* plocal_symbols);
2089 // Scan the relocations to look for symbol adjustments.
2091 scan_relocs(Symbol_table* symtab,
2093 Sized_relobj<32, big_endian>* object,
2094 unsigned int data_shndx,
2095 unsigned int sh_type,
2096 const unsigned char* prelocs,
2098 Output_section* output_section,
2099 bool needs_special_offset_handling,
2100 size_t local_symbol_count,
2101 const unsigned char* plocal_symbols);
2103 // Finalize the sections.
2105 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
2107 // Return the value to use for a dynamic symbol which requires special
2110 do_dynsym_value(const Symbol*) const;
2112 // Relocate a section.
2114 relocate_section(const Relocate_info<32, big_endian>*,
2115 unsigned int sh_type,
2116 const unsigned char* prelocs,
2118 Output_section* output_section,
2119 bool needs_special_offset_handling,
2120 unsigned char* view,
2121 Arm_address view_address,
2122 section_size_type view_size,
2123 const Reloc_symbol_changes*);
2125 // Scan the relocs during a relocatable link.
2127 scan_relocatable_relocs(Symbol_table* symtab,
2129 Sized_relobj<32, big_endian>* object,
2130 unsigned int data_shndx,
2131 unsigned int sh_type,
2132 const unsigned char* prelocs,
2134 Output_section* output_section,
2135 bool needs_special_offset_handling,
2136 size_t local_symbol_count,
2137 const unsigned char* plocal_symbols,
2138 Relocatable_relocs*);
2140 // Relocate a section during a relocatable link.
2142 relocate_for_relocatable(const Relocate_info<32, big_endian>*,
2143 unsigned int sh_type,
2144 const unsigned char* prelocs,
2146 Output_section* output_section,
2147 off_t offset_in_output_section,
2148 const Relocatable_relocs*,
2149 unsigned char* view,
2150 Arm_address view_address,
2151 section_size_type view_size,
2152 unsigned char* reloc_view,
2153 section_size_type reloc_view_size);
2155 // Return whether SYM is defined by the ABI.
2157 do_is_defined_by_abi(Symbol* sym) const
2158 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
2160 // Return whether there is a GOT section.
2162 has_got_section() const
2163 { return this->got_ != NULL; }
2165 // Return the size of the GOT section.
2169 gold_assert(this->got_ != NULL);
2170 return this->got_->data_size();
2173 // Map platform-specific reloc types
2175 get_real_reloc_type (unsigned int r_type);
2178 // Methods to support stub-generations.
2181 // Return the stub factory
2183 stub_factory() const
2184 { return this->stub_factory_; }
2186 // Make a new Arm_input_section object.
2187 Arm_input_section<big_endian>*
2188 new_arm_input_section(Relobj*, unsigned int);
2190 // Find the Arm_input_section object corresponding to the SHNDX-th input
2191 // section of RELOBJ.
2192 Arm_input_section<big_endian>*
2193 find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
2195 // Make a new Stub_table
2196 Stub_table<big_endian>*
2197 new_stub_table(Arm_input_section<big_endian>*);
2199 // Scan a section for stub generation.
2201 scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
2202 const unsigned char*, size_t, Output_section*,
2203 bool, const unsigned char*, Arm_address,
2208 relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
2209 Output_section*, unsigned char*, Arm_address,
2212 // Get the default ARM target.
2213 static Target_arm<big_endian>*
2216 gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
2217 && parameters->target().is_big_endian() == big_endian);
2218 return static_cast<Target_arm<big_endian>*>(
2219 parameters->sized_target<32, big_endian>());
2222 // Whether NAME belongs to a mapping symbol.
2224 is_mapping_symbol_name(const char* name)
2228 && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
2229 && (name[2] == '\0' || name[2] == '.'));
2232 // Whether we work around the Cortex-A8 erratum.
2234 fix_cortex_a8() const
2235 { return this->fix_cortex_a8_; }
2237 // Whether we fix R_ARM_V4BX relocation.
2239 // 1 - replace with MOV instruction (armv4 target)
2240 // 2 - make interworking veneer (>= armv4t targets only)
2241 General_options::Fix_v4bx
2243 { return parameters->options().fix_v4bx(); }
2245 // Scan a span of THUMB code section for Cortex-A8 erratum.
2247 scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
2248 section_size_type, section_size_type,
2249 const unsigned char*, Arm_address);
2251 // Apply Cortex-A8 workaround to a branch.
2253 apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
2254 unsigned char*, Arm_address);
2257 // Make an ELF object.
2259 do_make_elf_object(const std::string&, Input_file*, off_t,
2260 const elfcpp::Ehdr<32, big_endian>& ehdr);
2263 do_make_elf_object(const std::string&, Input_file*, off_t,
2264 const elfcpp::Ehdr<32, !big_endian>&)
2265 { gold_unreachable(); }
2268 do_make_elf_object(const std::string&, Input_file*, off_t,
2269 const elfcpp::Ehdr<64, false>&)
2270 { gold_unreachable(); }
2273 do_make_elf_object(const std::string&, Input_file*, off_t,
2274 const elfcpp::Ehdr<64, true>&)
2275 { gold_unreachable(); }
2277 // Make an output section.
2279 do_make_output_section(const char* name, elfcpp::Elf_Word type,
2280 elfcpp::Elf_Xword flags)
2281 { return new Arm_output_section<big_endian>(name, type, flags); }
2284 do_adjust_elf_header(unsigned char* view, int len) const;
2286 // We only need to generate stubs, and hence perform relaxation if we are
2287 // not doing relocatable linking.
2289 do_may_relax() const
2290 { return !parameters->options().relocatable(); }
2293 do_relax(int, const Input_objects*, Symbol_table*, Layout*);
2295 // Determine whether an object attribute tag takes an integer, a
2298 do_attribute_arg_type(int tag) const;
2300 // Reorder tags during output.
2302 do_attributes_order(int num) const;
2304 // This is called when the target is selected as the default.
2306 do_select_as_default_target()
2308 // No locking is required since there should only be one default target.
2309 // We cannot have both the big-endian and little-endian ARM targets
2311 gold_assert(arm_reloc_property_table == NULL);
2312 arm_reloc_property_table = new Arm_reloc_property_table();
2316 // The class which scans relocations.
2321 : issued_non_pic_error_(false)
2325 local(Symbol_table* symtab, Layout* layout, Target_arm* target,
2326 Sized_relobj<32, big_endian>* object,
2327 unsigned int data_shndx,
2328 Output_section* output_section,
2329 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2330 const elfcpp::Sym<32, big_endian>& lsym);
2333 global(Symbol_table* symtab, Layout* layout, Target_arm* target,
2334 Sized_relobj<32, big_endian>* object,
2335 unsigned int data_shndx,
2336 Output_section* output_section,
2337 const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
2341 local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2342 Sized_relobj<32, big_endian>* ,
2345 const elfcpp::Rel<32, big_endian>& ,
2347 const elfcpp::Sym<32, big_endian>&)
2351 global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
2352 Sized_relobj<32, big_endian>* ,
2355 const elfcpp::Rel<32, big_endian>& ,
2356 unsigned int , Symbol*)
2361 unsupported_reloc_local(Sized_relobj<32, big_endian>*,
2362 unsigned int r_type);
2365 unsupported_reloc_global(Sized_relobj<32, big_endian>*,
2366 unsigned int r_type, Symbol*);
2369 check_non_pic(Relobj*, unsigned int r_type);
2371 // Almost identical to Symbol::needs_plt_entry except that it also
2372 // handles STT_ARM_TFUNC.
2374 symbol_needs_plt_entry(const Symbol* sym)
2376 // An undefined symbol from an executable does not need a PLT entry.
2377 if (sym->is_undefined() && !parameters->options().shared())
2380 return (!parameters->doing_static_link()
2381 && (sym->type() == elfcpp::STT_FUNC
2382 || sym->type() == elfcpp::STT_ARM_TFUNC)
2383 && (sym->is_from_dynobj()
2384 || sym->is_undefined()
2385 || sym->is_preemptible()));
2388 // Whether we have issued an error about a non-PIC compilation.
2389 bool issued_non_pic_error_;
2392 // The class which implements relocation.
2402 // Return whether the static relocation needs to be applied.
2404 should_apply_static_reloc(const Sized_symbol<32>* gsym,
2407 Output_section* output_section);
2409 // Do a relocation. Return false if the caller should not issue
2410 // any warnings about this relocation.
2412 relocate(const Relocate_info<32, big_endian>*, Target_arm*,
2413 Output_section*, size_t relnum,
2414 const elfcpp::Rel<32, big_endian>&,
2415 unsigned int r_type, const Sized_symbol<32>*,
2416 const Symbol_value<32>*,
2417 unsigned char*, Arm_address,
2420 // Return whether we want to pass flag NON_PIC_REF for this
2421 // reloc. This means the relocation type accesses a symbol not via
2424 reloc_is_non_pic (unsigned int r_type)
2428 // These relocation types reference GOT or PLT entries explicitly.
2429 case elfcpp::R_ARM_GOT_BREL:
2430 case elfcpp::R_ARM_GOT_ABS:
2431 case elfcpp::R_ARM_GOT_PREL:
2432 case elfcpp::R_ARM_GOT_BREL12:
2433 case elfcpp::R_ARM_PLT32_ABS:
2434 case elfcpp::R_ARM_TLS_GD32:
2435 case elfcpp::R_ARM_TLS_LDM32:
2436 case elfcpp::R_ARM_TLS_IE32:
2437 case elfcpp::R_ARM_TLS_IE12GP:
2439 // These relocate types may use PLT entries.
2440 case elfcpp::R_ARM_CALL:
2441 case elfcpp::R_ARM_THM_CALL:
2442 case elfcpp::R_ARM_JUMP24:
2443 case elfcpp::R_ARM_THM_JUMP24:
2444 case elfcpp::R_ARM_THM_JUMP19:
2445 case elfcpp::R_ARM_PLT32:
2446 case elfcpp::R_ARM_THM_XPC22:
2447 case elfcpp::R_ARM_PREL31:
2448 case elfcpp::R_ARM_SBREL31:
2457 // Do a TLS relocation.
2458 inline typename Arm_relocate_functions<big_endian>::Status
2459 relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
2460 size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
2461 const Sized_symbol<32>*, const Symbol_value<32>*,
2462 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
2467 // A class which returns the size required for a relocation type,
2468 // used while scanning relocs during a relocatable link.
2469 class Relocatable_size_for_reloc
2473 get_size_for_reloc(unsigned int, Relobj*);
2476 // Adjust TLS relocation type based on the options and whether this
2477 // is a local symbol.
2478 static tls::Tls_optimization
2479 optimize_tls_reloc(bool is_final, int r_type);
2481 // Get the GOT section, creating it if necessary.
2482 Arm_output_data_got<big_endian>*
2483 got_section(Symbol_table*, Layout*);
2485 // Get the GOT PLT section.
2487 got_plt_section() const
2489 gold_assert(this->got_plt_ != NULL);
2490 return this->got_plt_;
2493 // Create a PLT entry for a global symbol.
2495 make_plt_entry(Symbol_table*, Layout*, Symbol*);
2497 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2499 define_tls_base_symbol(Symbol_table*, Layout*);
2501 // Create a GOT entry for the TLS module index.
2503 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2504 Sized_relobj<32, big_endian>* object);
2506 // Get the PLT section.
2507 const Output_data_plt_arm<big_endian>*
2510 gold_assert(this->plt_ != NULL);
2514 // Get the dynamic reloc section, creating it if necessary.
2516 rel_dyn_section(Layout*);
2518 // Get the section to use for TLS_DESC relocations.
2520 rel_tls_desc_section(Layout*) const;
2522 // Return true if the symbol may need a COPY relocation.
2523 // References from an executable object to non-function symbols
2524 // defined in a dynamic object may need a COPY relocation.
2526 may_need_copy_reloc(Symbol* gsym)
2528 return (gsym->type() != elfcpp::STT_ARM_TFUNC
2529 && gsym->may_need_copy_reloc());
2532 // Add a potential copy relocation.
2534 copy_reloc(Symbol_table* symtab, Layout* layout,
2535 Sized_relobj<32, big_endian>* object,
2536 unsigned int shndx, Output_section* output_section,
2537 Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
2539 this->copy_relocs_.copy_reloc(symtab, layout,
2540 symtab->get_sized_symbol<32>(sym),
2541 object, shndx, output_section, reloc,
2542 this->rel_dyn_section(layout));
2545 // Whether two EABI versions are compatible.
2547 are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
2549 // Merge processor-specific flags from input object and those in the ELF
2550 // header of the output.
2552 merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
2554 // Get the secondary compatible architecture.
2556 get_secondary_compatible_arch(const Attributes_section_data*);
2558 // Set the secondary compatible architecture.
2560 set_secondary_compatible_arch(Attributes_section_data*, int);
2563 tag_cpu_arch_combine(const char*, int, int*, int, int);
2565 // Helper to print AEABI enum tag value.
2567 aeabi_enum_name(unsigned int);
2569 // Return string value for TAG_CPU_name.
2571 tag_cpu_name_value(unsigned int);
2573 // Merge object attributes from input object and those in the output.
2575 merge_object_attributes(const char*, const Attributes_section_data*);
2577 // Helper to get an AEABI object attribute
2579 get_aeabi_object_attribute(int tag) const
2581 Attributes_section_data* pasd = this->attributes_section_data_;
2582 gold_assert(pasd != NULL);
2583 Object_attribute* attr =
2584 pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
2585 gold_assert(attr != NULL);
2590 // Methods to support stub-generations.
2593 // Group input sections for stub generation.
2595 group_sections(Layout*, section_size_type, bool);
2597 // Scan a relocation for stub generation.
2599 scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
2600 const Sized_symbol<32>*, unsigned int,
2601 const Symbol_value<32>*,
2602 elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
2604 // Scan a relocation section for stub.
2605 template<int sh_type>
2607 scan_reloc_section_for_stubs(
2608 const Relocate_info<32, big_endian>* relinfo,
2609 const unsigned char* prelocs,
2611 Output_section* output_section,
2612 bool needs_special_offset_handling,
2613 const unsigned char* view,
2614 elfcpp::Elf_types<32>::Elf_Addr view_address,
2617 // Fix .ARM.exidx section coverage.
2619 fix_exidx_coverage(Layout*, Arm_output_section<big_endian>*, Symbol_table*);
2621 // Functors for STL set.
2622 struct output_section_address_less_than
2625 operator()(const Output_section* s1, const Output_section* s2) const
2626 { return s1->address() < s2->address(); }
2629 // Information about this specific target which we pass to the
2630 // general Target structure.
2631 static const Target::Target_info arm_info;
2633 // The types of GOT entries needed for this platform.
2636 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
2637 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
2638 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
2639 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
2640 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
2643 typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
2645 // Map input section to Arm_input_section.
2646 typedef Unordered_map<Section_id,
2647 Arm_input_section<big_endian>*,
2649 Arm_input_section_map;
2651 // Map output addresses to relocs for Cortex-A8 erratum.
2652 typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
2653 Cortex_a8_relocs_info;
2656 Arm_output_data_got<big_endian>* got_;
2658 Output_data_plt_arm<big_endian>* plt_;
2659 // The GOT PLT section.
2660 Output_data_space* got_plt_;
2661 // The dynamic reloc section.
2662 Reloc_section* rel_dyn_;
2663 // Relocs saved to avoid a COPY reloc.
2664 Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
2665 // Space for variables copied with a COPY reloc.
2666 Output_data_space* dynbss_;
2667 // Offset of the GOT entry for the TLS module index.
2668 unsigned int got_mod_index_offset_;
2669 // True if the _TLS_MODULE_BASE_ symbol has been defined.
2670 bool tls_base_symbol_defined_;
2671 // Vector of Stub_tables created.
2672 Stub_table_list stub_tables_;
2674 const Stub_factory &stub_factory_;
2675 // Whether we can use BLX.
2677 // Whether we force PIC branch veneers.
2678 bool should_force_pic_veneer_;
2679 // Map for locating Arm_input_sections.
2680 Arm_input_section_map arm_input_section_map_;
2681 // Attributes section data in output.
2682 Attributes_section_data* attributes_section_data_;
2683 // Whether we want to fix code for Cortex-A8 erratum.
2684 bool fix_cortex_a8_;
2685 // Map addresses to relocs for Cortex-A8 erratum.
2686 Cortex_a8_relocs_info cortex_a8_relocs_info_;
2689 template<bool big_endian>
2690 const Target::Target_info Target_arm<big_endian>::arm_info =
2693 big_endian, // is_big_endian
2694 elfcpp::EM_ARM, // machine_code
2695 false, // has_make_symbol
2696 false, // has_resolve
2697 false, // has_code_fill
2698 true, // is_default_stack_executable
2700 "/usr/lib/libc.so.1", // dynamic_linker
2701 0x8000, // default_text_segment_address
2702 0x1000, // abi_pagesize (overridable by -z max-page-size)
2703 0x1000, // common_pagesize (overridable by -z common-page-size)
2704 elfcpp::SHN_UNDEF, // small_common_shndx
2705 elfcpp::SHN_UNDEF, // large_common_shndx
2706 0, // small_common_section_flags
2707 0, // large_common_section_flags
2708 ".ARM.attributes", // attributes_section
2709 "aeabi" // attributes_vendor
2712 // Arm relocate functions class
2715 template<bool big_endian>
2716 class Arm_relocate_functions : public Relocate_functions<32, big_endian>
2721 STATUS_OKAY, // No error during relocation.
2722 STATUS_OVERFLOW, // Relocation oveflow.
2723 STATUS_BAD_RELOC // Relocation cannot be applied.
2727 typedef Relocate_functions<32, big_endian> Base;
2728 typedef Arm_relocate_functions<big_endian> This;
2730 // Encoding of imm16 argument for movt and movw ARM instructions
2733 // imm16 := imm4 | imm12
2735 // 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
2736 // +-------+---------------+-------+-------+-----------------------+
2737 // | | |imm4 | |imm12 |
2738 // +-------+---------------+-------+-------+-----------------------+
2740 // Extract the relocation addend from VAL based on the ARM
2741 // instruction encoding described above.
2742 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2743 extract_arm_movw_movt_addend(
2744 typename elfcpp::Swap<32, big_endian>::Valtype val)
2746 // According to the Elf ABI for ARM Architecture the immediate
2747 // field is sign-extended to form the addend.
2748 return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
2751 // Insert X into VAL based on the ARM instruction encoding described
2753 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2754 insert_val_arm_movw_movt(
2755 typename elfcpp::Swap<32, big_endian>::Valtype val,
2756 typename elfcpp::Swap<32, big_endian>::Valtype x)
2760 val |= (x & 0xf000) << 4;
2764 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2767 // imm16 := imm4 | i | imm3 | imm8
2769 // 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
2770 // +---------+-+-----------+-------++-+-----+-------+---------------+
2771 // | |i| |imm4 || |imm3 | |imm8 |
2772 // +---------+-+-----------+-------++-+-----+-------+---------------+
2774 // Extract the relocation addend from VAL based on the Thumb2
2775 // instruction encoding described above.
2776 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2777 extract_thumb_movw_movt_addend(
2778 typename elfcpp::Swap<32, big_endian>::Valtype val)
2780 // According to the Elf ABI for ARM Architecture the immediate
2781 // field is sign-extended to form the addend.
2782 return utils::sign_extend<16>(((val >> 4) & 0xf000)
2783 | ((val >> 15) & 0x0800)
2784 | ((val >> 4) & 0x0700)
2788 // Insert X into VAL based on the Thumb2 instruction encoding
2790 static inline typename elfcpp::Swap<32, big_endian>::Valtype
2791 insert_val_thumb_movw_movt(
2792 typename elfcpp::Swap<32, big_endian>::Valtype val,
2793 typename elfcpp::Swap<32, big_endian>::Valtype x)
2796 val |= (x & 0xf000) << 4;
2797 val |= (x & 0x0800) << 15;
2798 val |= (x & 0x0700) << 4;
2799 val |= (x & 0x00ff);
2803 // Calculate the smallest constant Kn for the specified residual.
2804 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2806 calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
2812 // Determine the most significant bit in the residual and
2813 // align the resulting value to a 2-bit boundary.
2814 for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
2816 // The desired shift is now (msb - 6), or zero, whichever
2818 return (((msb - 6) < 0) ? 0 : (msb - 6));
2821 // Calculate the final residual for the specified group index.
2822 // If the passed group index is less than zero, the method will return
2823 // the value of the specified residual without any change.
2824 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2825 static typename elfcpp::Swap<32, big_endian>::Valtype
2826 calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2829 for (int n = 0; n <= group; n++)
2831 // Calculate which part of the value to mask.
2832 uint32_t shift = calc_grp_kn(residual);
2833 // Calculate the residual for the next time around.
2834 residual &= ~(residual & (0xff << shift));
2840 // Calculate the value of Gn for the specified group index.
2841 // We return it in the form of an encoded constant-and-rotation.
2842 // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
2843 static typename elfcpp::Swap<32, big_endian>::Valtype
2844 calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
2847 typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
2850 for (int n = 0; n <= group; n++)
2852 // Calculate which part of the value to mask.
2853 shift = calc_grp_kn(residual);
2854 // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
2855 gn = residual & (0xff << shift);
2856 // Calculate the residual for the next time around.
2859 // Return Gn in the form of an encoded constant-and-rotation.
2860 return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
2864 // Handle ARM long branches.
2865 static typename This::Status
2866 arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2867 unsigned char *, const Sized_symbol<32>*,
2868 const Arm_relobj<big_endian>*, unsigned int,
2869 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2871 // Handle THUMB long branches.
2872 static typename This::Status
2873 thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
2874 unsigned char *, const Sized_symbol<32>*,
2875 const Arm_relobj<big_endian>*, unsigned int,
2876 const Symbol_value<32>*, Arm_address, Arm_address, bool);
2879 // Return the branch offset of a 32-bit THUMB branch.
2880 static inline int32_t
2881 thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2883 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
2884 // involving the J1 and J2 bits.
2885 uint32_t s = (upper_insn & (1U << 10)) >> 10;
2886 uint32_t upper = upper_insn & 0x3ffU;
2887 uint32_t lower = lower_insn & 0x7ffU;
2888 uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
2889 uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
2890 uint32_t i1 = j1 ^ s ? 0 : 1;
2891 uint32_t i2 = j2 ^ s ? 0 : 1;
2893 return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
2894 | (upper << 12) | (lower << 1));
2897 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
2898 // UPPER_INSN is the original upper instruction of the branch. Caller is
2899 // responsible for overflow checking and BLX offset adjustment.
2900 static inline uint16_t
2901 thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
2903 uint32_t s = offset < 0 ? 1 : 0;
2904 uint32_t bits = static_cast<uint32_t>(offset);
2905 return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
2908 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
2909 // LOWER_INSN is the original lower instruction of the branch. Caller is
2910 // responsible for overflow checking and BLX offset adjustment.
2911 static inline uint16_t
2912 thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
2914 uint32_t s = offset < 0 ? 1 : 0;
2915 uint32_t bits = static_cast<uint32_t>(offset);
2916 return ((lower_insn & ~0x2fffU)
2917 | ((((bits >> 23) & 1) ^ !s) << 13)
2918 | ((((bits >> 22) & 1) ^ !s) << 11)
2919 | ((bits >> 1) & 0x7ffU));
2922 // Return the branch offset of a 32-bit THUMB conditional branch.
2923 static inline int32_t
2924 thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
2926 uint32_t s = (upper_insn & 0x0400U) >> 10;
2927 uint32_t j1 = (lower_insn & 0x2000U) >> 13;
2928 uint32_t j2 = (lower_insn & 0x0800U) >> 11;
2929 uint32_t lower = (lower_insn & 0x07ffU);
2930 uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
2932 return utils::sign_extend<21>((upper << 12) | (lower << 1));
2935 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
2936 // instruction. UPPER_INSN is the original upper instruction of the branch.
2937 // Caller is responsible for overflow checking.
2938 static inline uint16_t
2939 thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
2941 uint32_t s = offset < 0 ? 1 : 0;
2942 uint32_t bits = static_cast<uint32_t>(offset);
2943 return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
2946 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
2947 // instruction. LOWER_INSN is the original lower instruction of the branch.
2948 // Caller is reponsible for overflow checking.
2949 static inline uint16_t
2950 thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
2952 uint32_t bits = static_cast<uint32_t>(offset);
2953 uint32_t j2 = (bits & 0x00080000U) >> 19;
2954 uint32_t j1 = (bits & 0x00040000U) >> 18;
2955 uint32_t lo = (bits & 0x00000ffeU) >> 1;
2957 return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
2960 // R_ARM_ABS8: S + A
2961 static inline typename This::Status
2962 abs8(unsigned char *view,
2963 const Sized_relobj<32, big_endian>* object,
2964 const Symbol_value<32>* psymval)
2966 typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
2967 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2968 Valtype* wv = reinterpret_cast<Valtype*>(view);
2969 Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
2970 Reltype addend = utils::sign_extend<8>(val);
2971 Reltype x = psymval->value(object, addend);
2972 val = utils::bit_select(val, x, 0xffU);
2973 elfcpp::Swap<8, big_endian>::writeval(wv, val);
2974 return (utils::has_signed_unsigned_overflow<8>(x)
2975 ? This::STATUS_OVERFLOW
2976 : This::STATUS_OKAY);
2979 // R_ARM_THM_ABS5: S + A
2980 static inline typename This::Status
2981 thm_abs5(unsigned char *view,
2982 const Sized_relobj<32, big_endian>* object,
2983 const Symbol_value<32>* psymval)
2985 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
2986 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
2987 Valtype* wv = reinterpret_cast<Valtype*>(view);
2988 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
2989 Reltype addend = (val & 0x7e0U) >> 6;
2990 Reltype x = psymval->value(object, addend);
2991 val = utils::bit_select(val, x << 6, 0x7e0U);
2992 elfcpp::Swap<16, big_endian>::writeval(wv, val);
2993 return (utils::has_overflow<5>(x)
2994 ? This::STATUS_OVERFLOW
2995 : This::STATUS_OKAY);
2998 // R_ARM_ABS12: S + A
2999 static inline typename This::Status
3000 abs12(unsigned char *view,
3001 const Sized_relobj<32, big_endian>* object,
3002 const Symbol_value<32>* psymval)
3004 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3005 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3006 Valtype* wv = reinterpret_cast<Valtype*>(view);
3007 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3008 Reltype addend = val & 0x0fffU;
3009 Reltype x = psymval->value(object, addend);
3010 val = utils::bit_select(val, x, 0x0fffU);
3011 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3012 return (utils::has_overflow<12>(x)
3013 ? This::STATUS_OVERFLOW
3014 : This::STATUS_OKAY);
3017 // R_ARM_ABS16: S + A
3018 static inline typename This::Status
3019 abs16(unsigned char *view,
3020 const Sized_relobj<32, big_endian>* object,
3021 const Symbol_value<32>* psymval)
3023 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3024 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3025 Valtype* wv = reinterpret_cast<Valtype*>(view);
3026 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3027 Reltype addend = utils::sign_extend<16>(val);
3028 Reltype x = psymval->value(object, addend);
3029 val = utils::bit_select(val, x, 0xffffU);
3030 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3031 return (utils::has_signed_unsigned_overflow<16>(x)
3032 ? This::STATUS_OVERFLOW
3033 : This::STATUS_OKAY);
3036 // R_ARM_ABS32: (S + A) | T
3037 static inline typename This::Status
3038 abs32(unsigned char *view,
3039 const Sized_relobj<32, big_endian>* object,
3040 const Symbol_value<32>* psymval,
3041 Arm_address thumb_bit)
3043 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3044 Valtype* wv = reinterpret_cast<Valtype*>(view);
3045 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3046 Valtype x = psymval->value(object, addend) | thumb_bit;
3047 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3048 return This::STATUS_OKAY;
3051 // R_ARM_REL32: (S + A) | T - P
3052 static inline typename This::Status
3053 rel32(unsigned char *view,
3054 const Sized_relobj<32, big_endian>* object,
3055 const Symbol_value<32>* psymval,
3056 Arm_address address,
3057 Arm_address thumb_bit)
3059 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3060 Valtype* wv = reinterpret_cast<Valtype*>(view);
3061 Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
3062 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3063 elfcpp::Swap<32, big_endian>::writeval(wv, x);
3064 return This::STATUS_OKAY;
3067 // R_ARM_THM_JUMP24: (S + A) | T - P
3068 static typename This::Status
3069 thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object,
3070 const Symbol_value<32>* psymval, Arm_address address,
3071 Arm_address thumb_bit);
3073 // R_ARM_THM_JUMP6: S + A – P
3074 static inline typename This::Status
3075 thm_jump6(unsigned char *view,
3076 const Sized_relobj<32, big_endian>* object,
3077 const Symbol_value<32>* psymval,
3078 Arm_address address)
3080 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3081 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3082 Valtype* wv = reinterpret_cast<Valtype*>(view);
3083 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3084 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
3085 Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
3086 Reltype x = (psymval->value(object, addend) - address);
3087 val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
3088 elfcpp::Swap<16, big_endian>::writeval(wv, val);
3089 // CZB does only forward jumps.
3090 return ((x > 0x007e)
3091 ? This::STATUS_OVERFLOW
3092 : This::STATUS_OKAY);
3095 // R_ARM_THM_JUMP8: S + A – P
3096 static inline typename This::Status
3097 thm_jump8(unsigned char *view,
3098 const Sized_relobj<32, big_endian>* object,
3099 const Symbol_value<32>* psymval,
3100 Arm_address address)
3102 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3103 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3104 Valtype* wv = reinterpret_cast<Valtype*>(view);
3105 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3106 Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
3107 Reltype x = (psymval->value(object, addend) - address);
3108 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
3109 return (utils::has_overflow<8>(x)
3110 ? This::STATUS_OVERFLOW
3111 : This::STATUS_OKAY);
3114 // R_ARM_THM_JUMP11: S + A – P
3115 static inline typename This::Status
3116 thm_jump11(unsigned char *view,
3117 const Sized_relobj<32, big_endian>* object,
3118 const Symbol_value<32>* psymval,
3119 Arm_address address)
3121 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3122 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3123 Valtype* wv = reinterpret_cast<Valtype*>(view);
3124 Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
3125 Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
3126 Reltype x = (psymval->value(object, addend) - address);
3127 elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
3128 return (utils::has_overflow<11>(x)
3129 ? This::STATUS_OVERFLOW
3130 : This::STATUS_OKAY);
3133 // R_ARM_BASE_PREL: B(S) + A - P
3134 static inline typename This::Status
3135 base_prel(unsigned char* view,
3137 Arm_address address)
3139 Base::rel32(view, origin - address);
3143 // R_ARM_BASE_ABS: B(S) + A
3144 static inline typename This::Status
3145 base_abs(unsigned char* view,
3148 Base::rel32(view, origin);
3152 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
3153 static inline typename This::Status
3154 got_brel(unsigned char* view,
3155 typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
3157 Base::rel32(view, got_offset);
3158 return This::STATUS_OKAY;
3161 // R_ARM_GOT_PREL: GOT(S) + A - P
3162 static inline typename This::Status
3163 got_prel(unsigned char *view,
3164 Arm_address got_entry,
3165 Arm_address address)
3167 Base::rel32(view, got_entry - address);
3168 return This::STATUS_OKAY;
3171 // R_ARM_PREL: (S + A) | T - P
3172 static inline typename This::Status
3173 prel31(unsigned char *view,
3174 const Sized_relobj<32, big_endian>* object,
3175 const Symbol_value<32>* psymval,
3176 Arm_address address,
3177 Arm_address thumb_bit)
3179 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3180 Valtype* wv = reinterpret_cast<Valtype*>(view);
3181 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3182 Valtype addend = utils::sign_extend<31>(val);
3183 Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
3184 val = utils::bit_select(val, x, 0x7fffffffU);
3185 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3186 return (utils::has_overflow<31>(x) ?
3187 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3190 // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
3191 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
3192 // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3193 // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
3194 static inline typename This::Status
3195 movw(unsigned char* view,
3196 const Sized_relobj<32, big_endian>* object,
3197 const Symbol_value<32>* psymval,
3198 Arm_address relative_address_base,
3199 Arm_address thumb_bit,
3200 bool check_overflow)
3202 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3203 Valtype* wv = reinterpret_cast<Valtype*>(view);
3204 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3205 Valtype addend = This::extract_arm_movw_movt_addend(val);
3206 Valtype x = ((psymval->value(object, addend) | thumb_bit)
3207 - relative_address_base);
3208 val = This::insert_val_arm_movw_movt(val, x);
3209 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3210 return ((check_overflow && utils::has_overflow<16>(x))
3211 ? This::STATUS_OVERFLOW
3212 : This::STATUS_OKAY);
3215 // R_ARM_MOVT_ABS: S + A (relative address base is 0)
3216 // R_ARM_MOVT_PREL: S + A - P
3217 // R_ARM_MOVT_BREL: S + A - B(S)
3218 static inline typename This::Status
3219 movt(unsigned char* view,
3220 const Sized_relobj<32, big_endian>* object,
3221 const Symbol_value<32>* psymval,
3222 Arm_address relative_address_base)
3224 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3225 Valtype* wv = reinterpret_cast<Valtype*>(view);
3226 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3227 Valtype addend = This::extract_arm_movw_movt_addend(val);
3228 Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3229 val = This::insert_val_arm_movw_movt(val, x);
3230 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3231 // FIXME: IHI0044D says that we should check for overflow.
3232 return This::STATUS_OKAY;
3235 // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
3236 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
3237 // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
3238 // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
3239 static inline typename This::Status
3240 thm_movw(unsigned char *view,
3241 const Sized_relobj<32, big_endian>* object,
3242 const Symbol_value<32>* psymval,
3243 Arm_address relative_address_base,
3244 Arm_address thumb_bit,
3245 bool check_overflow)
3247 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3248 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3249 Valtype* wv = reinterpret_cast<Valtype*>(view);
3250 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3251 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3252 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3254 (psymval->value(object, addend) | thumb_bit) - relative_address_base;
3255 val = This::insert_val_thumb_movw_movt(val, x);
3256 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3257 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3258 return ((check_overflow && utils::has_overflow<16>(x))
3259 ? This::STATUS_OVERFLOW
3260 : This::STATUS_OKAY);
3263 // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
3264 // R_ARM_THM_MOVT_PREL: S + A - P
3265 // R_ARM_THM_MOVT_BREL: S + A - B(S)
3266 static inline typename This::Status
3267 thm_movt(unsigned char* view,
3268 const Sized_relobj<32, big_endian>* object,
3269 const Symbol_value<32>* psymval,
3270 Arm_address relative_address_base)
3272 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3273 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3274 Valtype* wv = reinterpret_cast<Valtype*>(view);
3275 Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3276 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3277 Reltype addend = This::extract_thumb_movw_movt_addend(val);
3278 Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
3279 val = This::insert_val_thumb_movw_movt(val, x);
3280 elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
3281 elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
3282 return This::STATUS_OKAY;
3285 // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
3286 static inline typename This::Status
3287 thm_alu11(unsigned char* view,
3288 const Sized_relobj<32, big_endian>* object,
3289 const Symbol_value<32>* psymval,
3290 Arm_address address,
3291 Arm_address thumb_bit)
3293 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3294 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3295 Valtype* wv = reinterpret_cast<Valtype*>(view);
3296 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3297 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3299 // 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
3300 // -----------------------------------------------------------------------
3301 // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
3302 // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
3303 // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
3304 // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
3305 // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
3306 // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
3308 // Determine a sign for the addend.
3309 const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
3310 || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
3311 // Thumb2 addend encoding:
3312 // imm12 := i | imm3 | imm8
3313 int32_t addend = (insn & 0xff)
3314 | ((insn & 0x00007000) >> 4)
3315 | ((insn & 0x04000000) >> 15);
3316 // Apply a sign to the added.
3319 int32_t x = (psymval->value(object, addend) | thumb_bit)
3320 - (address & 0xfffffffc);
3321 Reltype val = abs(x);
3322 // Mask out the value and a distinct part of the ADD/SUB opcode
3323 // (bits 7:5 of opword).
3324 insn = (insn & 0xfb0f8f00)
3326 | ((val & 0x700) << 4)
3327 | ((val & 0x800) << 15);
3328 // Set the opcode according to whether the value to go in the
3329 // place is negative.
3333 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3334 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3335 return ((val > 0xfff) ?
3336 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3339 // R_ARM_THM_PC8: S + A - Pa (Thumb)
3340 static inline typename This::Status
3341 thm_pc8(unsigned char* view,
3342 const Sized_relobj<32, big_endian>* object,
3343 const Symbol_value<32>* psymval,
3344 Arm_address address)
3346 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3347 typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
3348 Valtype* wv = reinterpret_cast<Valtype*>(view);
3349 Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
3350 Reltype addend = ((insn & 0x00ff) << 2);
3351 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3352 Reltype val = abs(x);
3353 insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
3355 elfcpp::Swap<16, big_endian>::writeval(wv, insn);
3356 return ((val > 0x03fc)
3357 ? This::STATUS_OVERFLOW
3358 : This::STATUS_OKAY);
3361 // R_ARM_THM_PC12: S + A - Pa (Thumb32)
3362 static inline typename This::Status
3363 thm_pc12(unsigned char* view,
3364 const Sized_relobj<32, big_endian>* object,
3365 const Symbol_value<32>* psymval,
3366 Arm_address address)
3368 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3369 typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
3370 Valtype* wv = reinterpret_cast<Valtype*>(view);
3371 Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
3372 | elfcpp::Swap<16, big_endian>::readval(wv + 1);
3373 // Determine a sign for the addend (positive if the U bit is 1).
3374 const int sign = (insn & 0x00800000) ? 1 : -1;
3375 int32_t addend = (insn & 0xfff);
3376 // Apply a sign to the added.
3379 int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
3380 Reltype val = abs(x);
3381 // Mask out and apply the value and the U bit.
3382 insn = (insn & 0xff7ff000) | (val & 0xfff);
3383 // Set the U bit according to whether the value to go in the
3384 // place is positive.
3388 elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
3389 elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
3390 return ((val > 0xfff) ?
3391 This::STATUS_OVERFLOW : This::STATUS_OKAY);
3395 static inline typename This::Status
3396 v4bx(const Relocate_info<32, big_endian>* relinfo,
3397 unsigned char *view,
3398 const Arm_relobj<big_endian>* object,
3399 const Arm_address address,
3400 const bool is_interworking)
3403 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3404 Valtype* wv = reinterpret_cast<Valtype*>(view);
3405 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3407 // Ensure that we have a BX instruction.
3408 gold_assert((val & 0x0ffffff0) == 0x012fff10);
3409 const uint32_t reg = (val & 0xf);
3410 if (is_interworking && reg != 0xf)
3412 Stub_table<big_endian>* stub_table =
3413 object->stub_table(relinfo->data_shndx);
3414 gold_assert(stub_table != NULL);
3416 Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
3417 gold_assert(stub != NULL);
3419 int32_t veneer_address =
3420 stub_table->address() + stub->offset() - 8 - address;
3421 gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
3422 && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
3423 // Replace with a branch to veneer (B <addr>)
3424 val = (val & 0xf0000000) | 0x0a000000
3425 | ((veneer_address >> 2) & 0x00ffffff);
3429 // Preserve Rm (lowest four bits) and the condition code
3430 // (highest four bits). Other bits encode MOV PC,Rm.
3431 val = (val & 0xf000000f) | 0x01a0f000;
3433 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3434 return This::STATUS_OKAY;
3437 // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
3438 // R_ARM_ALU_PC_G0: ((S + A) | T) - P
3439 // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
3440 // R_ARM_ALU_PC_G1: ((S + A) | T) - P
3441 // R_ARM_ALU_PC_G2: ((S + A) | T) - P
3442 // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
3443 // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
3444 // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
3445 // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
3446 // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
3447 static inline typename This::Status
3448 arm_grp_alu(unsigned char* view,
3449 const Sized_relobj<32, big_endian>* object,
3450 const Symbol_value<32>* psymval,
3452 Arm_address address,
3453 Arm_address thumb_bit,
3454 bool check_overflow)
3456 gold_assert(group >= 0 && group < 3);
3457 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3458 Valtype* wv = reinterpret_cast<Valtype*>(view);
3459 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3461 // ALU group relocations are allowed only for the ADD/SUB instructions.
3462 // (0x00800000 - ADD, 0x00400000 - SUB)
3463 const Valtype opcode = insn & 0x01e00000;
3464 if (opcode != 0x00800000 && opcode != 0x00400000)
3465 return This::STATUS_BAD_RELOC;
3467 // Determine a sign for the addend.
3468 const int sign = (opcode == 0x00800000) ? 1 : -1;
3469 // shifter = rotate_imm * 2
3470 const uint32_t shifter = (insn & 0xf00) >> 7;
3471 // Initial addend value.
3472 int32_t addend = insn & 0xff;
3473 // Rotate addend right by shifter.
3474 addend = (addend >> shifter) | (addend << (32 - shifter));
3475 // Apply a sign to the added.
3478 int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
3479 Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
3480 // Check for overflow if required
3482 && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
3483 return This::STATUS_OVERFLOW;
3485 // Mask out the value and the ADD/SUB part of the opcode; take care
3486 // not to destroy the S bit.
3488 // Set the opcode according to whether the value to go in the
3489 // place is negative.
3490 insn |= ((x < 0) ? 0x00400000 : 0x00800000);
3491 // Encode the offset (encoded Gn).
3494 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3495 return This::STATUS_OKAY;
3498 // R_ARM_LDR_PC_G0: S + A - P
3499 // R_ARM_LDR_PC_G1: S + A - P
3500 // R_ARM_LDR_PC_G2: S + A - P
3501 // R_ARM_LDR_SB_G0: S + A - B(S)
3502 // R_ARM_LDR_SB_G1: S + A - B(S)
3503 // R_ARM_LDR_SB_G2: S + A - B(S)
3504 static inline typename This::Status
3505 arm_grp_ldr(unsigned char* view,
3506 const Sized_relobj<32, big_endian>* object,
3507 const Symbol_value<32>* psymval,
3509 Arm_address address)
3511 gold_assert(group >= 0 && group < 3);
3512 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3513 Valtype* wv = reinterpret_cast<Valtype*>(view);
3514 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3516 const int sign = (insn & 0x00800000) ? 1 : -1;
3517 int32_t addend = (insn & 0xfff) * sign;
3518 int32_t x = (psymval->value(object, addend) - address);
3519 // Calculate the relevant G(n-1) value to obtain this stage residual.
3521 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3522 if (residual >= 0x1000)
3523 return This::STATUS_OVERFLOW;
3525 // Mask out the value and U bit.
3527 // Set the U bit for non-negative values.
3532 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3533 return This::STATUS_OKAY;
3536 // R_ARM_LDRS_PC_G0: S + A - P
3537 // R_ARM_LDRS_PC_G1: S + A - P
3538 // R_ARM_LDRS_PC_G2: S + A - P
3539 // R_ARM_LDRS_SB_G0: S + A - B(S)
3540 // R_ARM_LDRS_SB_G1: S + A - B(S)
3541 // R_ARM_LDRS_SB_G2: S + A - B(S)
3542 static inline typename This::Status
3543 arm_grp_ldrs(unsigned char* view,
3544 const Sized_relobj<32, big_endian>* object,
3545 const Symbol_value<32>* psymval,
3547 Arm_address address)
3549 gold_assert(group >= 0 && group < 3);
3550 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3551 Valtype* wv = reinterpret_cast<Valtype*>(view);
3552 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3554 const int sign = (insn & 0x00800000) ? 1 : -1;
3555 int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
3556 int32_t x = (psymval->value(object, addend) - address);
3557 // Calculate the relevant G(n-1) value to obtain this stage residual.
3559 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3560 if (residual >= 0x100)
3561 return This::STATUS_OVERFLOW;
3563 // Mask out the value and U bit.
3565 // Set the U bit for non-negative values.
3568 insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
3570 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3571 return This::STATUS_OKAY;
3574 // R_ARM_LDC_PC_G0: S + A - P
3575 // R_ARM_LDC_PC_G1: S + A - P
3576 // R_ARM_LDC_PC_G2: S + A - P
3577 // R_ARM_LDC_SB_G0: S + A - B(S)
3578 // R_ARM_LDC_SB_G1: S + A - B(S)
3579 // R_ARM_LDC_SB_G2: S + A - B(S)
3580 static inline typename This::Status
3581 arm_grp_ldc(unsigned char* view,
3582 const Sized_relobj<32, big_endian>* object,
3583 const Symbol_value<32>* psymval,
3585 Arm_address address)
3587 gold_assert(group >= 0 && group < 3);
3588 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3589 Valtype* wv = reinterpret_cast<Valtype*>(view);
3590 Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
3592 const int sign = (insn & 0x00800000) ? 1 : -1;
3593 int32_t addend = ((insn & 0xff) << 2) * sign;
3594 int32_t x = (psymval->value(object, addend) - address);
3595 // Calculate the relevant G(n-1) value to obtain this stage residual.
3597 Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
3598 if ((residual & 0x3) != 0 || residual >= 0x400)
3599 return This::STATUS_OVERFLOW;
3601 // Mask out the value and U bit.
3603 // Set the U bit for non-negative values.
3606 insn |= (residual >> 2);
3608 elfcpp::Swap<32, big_endian>::writeval(wv, insn);
3609 return This::STATUS_OKAY;
3613 // Relocate ARM long branches. This handles relocation types
3614 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
3615 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3616 // undefined and we do not use PLT in this relocation. In such a case,
3617 // the branch is converted into an NOP.
3619 template<bool big_endian>
3620 typename Arm_relocate_functions<big_endian>::Status
3621 Arm_relocate_functions<big_endian>::arm_branch_common(
3622 unsigned int r_type,
3623 const Relocate_info<32, big_endian>* relinfo,
3624 unsigned char *view,
3625 const Sized_symbol<32>* gsym,
3626 const Arm_relobj<big_endian>* object,
3628 const Symbol_value<32>* psymval,
3629 Arm_address address,
3630 Arm_address thumb_bit,
3631 bool is_weakly_undefined_without_plt)
3633 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
3634 Valtype* wv = reinterpret_cast<Valtype*>(view);
3635 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
3637 bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
3638 && ((val & 0x0f000000UL) == 0x0a000000UL);
3639 bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
3640 bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
3641 && ((val & 0x0f000000UL) == 0x0b000000UL);
3642 bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
3643 bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
3645 // Check that the instruction is valid.
3646 if (r_type == elfcpp::R_ARM_CALL)
3648 if (!insn_is_uncond_bl && !insn_is_blx)
3649 return This::STATUS_BAD_RELOC;
3651 else if (r_type == elfcpp::R_ARM_JUMP24)
3653 if (!insn_is_b && !insn_is_cond_bl)
3654 return This::STATUS_BAD_RELOC;
3656 else if (r_type == elfcpp::R_ARM_PLT32)
3658 if (!insn_is_any_branch)
3659 return This::STATUS_BAD_RELOC;
3661 else if (r_type == elfcpp::R_ARM_XPC25)
3663 // FIXME: AAELF document IH0044C does not say much about it other
3664 // than it being obsolete.
3665 if (!insn_is_any_branch)
3666 return This::STATUS_BAD_RELOC;
3671 // A branch to an undefined weak symbol is turned into a jump to
3672 // the next instruction unless a PLT entry will be created.
3673 // Do the same for local undefined symbols.
3674 // The jump to the next instruction is optimized as a NOP depending
3675 // on the architecture.
3676 const Target_arm<big_endian>* arm_target =
3677 Target_arm<big_endian>::default_target();
3678 if (is_weakly_undefined_without_plt)
3680 Valtype cond = val & 0xf0000000U;
3681 if (arm_target->may_use_arm_nop())
3682 val = cond | 0x0320f000;
3684 val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
3685 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3686 return This::STATUS_OKAY;
3689 Valtype addend = utils::sign_extend<26>(val << 2);
3690 Valtype branch_target = psymval->value(object, addend);
3691 int32_t branch_offset = branch_target - address;
3693 // We need a stub if the branch offset is too large or if we need
3695 bool may_use_blx = arm_target->may_use_blx();
3696 Reloc_stub* stub = NULL;
3697 if (utils::has_overflow<26>(branch_offset)
3698 || ((thumb_bit != 0) && !(may_use_blx && r_type == elfcpp::R_ARM_CALL)))
3700 Valtype unadjusted_branch_target = psymval->value(object, 0);
3702 Stub_type stub_type =
3703 Reloc_stub::stub_type_for_reloc(r_type, address,
3704 unadjusted_branch_target,
3706 if (stub_type != arm_stub_none)
3708 Stub_table<big_endian>* stub_table =
3709 object->stub_table(relinfo->data_shndx);
3710 gold_assert(stub_table != NULL);
3712 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3713 stub = stub_table->find_reloc_stub(stub_key);
3714 gold_assert(stub != NULL);
3715 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3716 branch_target = stub_table->address() + stub->offset() + addend;
3717 branch_offset = branch_target - address;
3718 gold_assert(!utils::has_overflow<26>(branch_offset));
3722 // At this point, if we still need to switch mode, the instruction
3723 // must either be a BLX or a BL that can be converted to a BLX.
3727 gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
3728 val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
3731 val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
3732 elfcpp::Swap<32, big_endian>::writeval(wv, val);
3733 return (utils::has_overflow<26>(branch_offset)
3734 ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
3737 // Relocate THUMB long branches. This handles relocation types
3738 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
3739 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3740 // undefined and we do not use PLT in this relocation. In such a case,
3741 // the branch is converted into an NOP.
3743 template<bool big_endian>
3744 typename Arm_relocate_functions<big_endian>::Status
3745 Arm_relocate_functions<big_endian>::thumb_branch_common(
3746 unsigned int r_type,
3747 const Relocate_info<32, big_endian>* relinfo,
3748 unsigned char *view,
3749 const Sized_symbol<32>* gsym,
3750 const Arm_relobj<big_endian>* object,
3752 const Symbol_value<32>* psymval,
3753 Arm_address address,
3754 Arm_address thumb_bit,
3755 bool is_weakly_undefined_without_plt)
3757 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3758 Valtype* wv = reinterpret_cast<Valtype*>(view);
3759 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3760 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3762 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
3764 bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
3765 bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
3767 // Check that the instruction is valid.
3768 if (r_type == elfcpp::R_ARM_THM_CALL)
3770 if (!is_bl_insn && !is_blx_insn)
3771 return This::STATUS_BAD_RELOC;
3773 else if (r_type == elfcpp::R_ARM_THM_JUMP24)
3775 // This cannot be a BLX.
3777 return This::STATUS_BAD_RELOC;
3779 else if (r_type == elfcpp::R_ARM_THM_XPC22)
3781 // Check for Thumb to Thumb call.
3783 return This::STATUS_BAD_RELOC;
3786 gold_warning(_("%s: Thumb BLX instruction targets "
3787 "thumb function '%s'."),
3788 object->name().c_str(),
3789 (gsym ? gsym->name() : "(local)"));
3790 // Convert BLX to BL.
3791 lower_insn |= 0x1000U;
3797 // A branch to an undefined weak symbol is turned into a jump to
3798 // the next instruction unless a PLT entry will be created.
3799 // The jump to the next instruction is optimized as a NOP.W for
3800 // Thumb-2 enabled architectures.
3801 const Target_arm<big_endian>* arm_target =
3802 Target_arm<big_endian>::default_target();
3803 if (is_weakly_undefined_without_plt)
3805 if (arm_target->may_use_thumb2_nop())
3807 elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
3808 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
3812 elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
3813 elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
3815 return This::STATUS_OKAY;
3818 int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
3819 Arm_address branch_target = psymval->value(object, addend);
3820 int32_t branch_offset = branch_target - address;
3822 // We need a stub if the branch offset is too large or if we need
3824 bool may_use_blx = arm_target->may_use_blx();
3825 bool thumb2 = arm_target->using_thumb2();
3826 if ((!thumb2 && utils::has_overflow<23>(branch_offset))
3827 || (thumb2 && utils::has_overflow<25>(branch_offset))
3828 || ((thumb_bit == 0)
3829 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
3830 || r_type == elfcpp::R_ARM_THM_JUMP24)))
3832 Arm_address unadjusted_branch_target = psymval->value(object, 0);
3834 Stub_type stub_type =
3835 Reloc_stub::stub_type_for_reloc(r_type, address,
3836 unadjusted_branch_target,
3839 if (stub_type != arm_stub_none)
3841 Stub_table<big_endian>* stub_table =
3842 object->stub_table(relinfo->data_shndx);
3843 gold_assert(stub_table != NULL);
3845 Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
3846 Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
3847 gold_assert(stub != NULL);
3848 thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
3849 branch_target = stub_table->address() + stub->offset() + addend;
3850 branch_offset = branch_target - address;
3854 // At this point, if we still need to switch mode, the instruction
3855 // must either be a BLX or a BL that can be converted to a BLX.
3858 gold_assert(may_use_blx
3859 && (r_type == elfcpp::R_ARM_THM_CALL
3860 || r_type == elfcpp::R_ARM_THM_XPC22));
3861 // Make sure this is a BLX.
3862 lower_insn &= ~0x1000U;
3866 // Make sure this is a BL.
3867 lower_insn |= 0x1000U;
3870 if ((lower_insn & 0x5000U) == 0x4000U)
3871 // For a BLX instruction, make sure that the relocation is rounded up
3872 // to a word boundary. This follows the semantics of the instruction
3873 // which specifies that bit 1 of the target address will come from bit
3874 // 1 of the base address.
3875 branch_offset = (branch_offset + 2) & ~3;
3877 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
3878 // We use the Thumb-2 encoding, which is safe even if dealing with
3879 // a Thumb-1 instruction by virtue of our overflow check above. */
3880 upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
3881 lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
3883 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3884 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3887 ? utils::has_overflow<25>(branch_offset)
3888 : utils::has_overflow<23>(branch_offset))
3889 ? This::STATUS_OVERFLOW
3890 : This::STATUS_OKAY);
3893 // Relocate THUMB-2 long conditional branches.
3894 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3895 // undefined and we do not use PLT in this relocation. In such a case,
3896 // the branch is converted into an NOP.
3898 template<bool big_endian>
3899 typename Arm_relocate_functions<big_endian>::Status
3900 Arm_relocate_functions<big_endian>::thm_jump19(
3901 unsigned char *view,
3902 const Arm_relobj<big_endian>* object,
3903 const Symbol_value<32>* psymval,
3904 Arm_address address,
3905 Arm_address thumb_bit)
3907 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
3908 Valtype* wv = reinterpret_cast<Valtype*>(view);
3909 uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
3910 uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
3911 int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
3913 Arm_address branch_target = psymval->value(object, addend);
3914 int32_t branch_offset = branch_target - address;
3916 // ??? Should handle interworking? GCC might someday try to
3917 // use this for tail calls.
3918 // FIXME: We do support thumb entry to PLT yet.
3921 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
3922 return This::STATUS_BAD_RELOC;
3925 // Put RELOCATION back into the insn.
3926 upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
3927 lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
3929 // Put the relocated value back in the object file:
3930 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
3931 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
3933 return (utils::has_overflow<21>(branch_offset)
3934 ? This::STATUS_OVERFLOW
3935 : This::STATUS_OKAY);
3938 // Get the GOT section, creating it if necessary.
3940 template<bool big_endian>
3941 Arm_output_data_got<big_endian>*
3942 Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
3944 if (this->got_ == NULL)
3946 gold_assert(symtab != NULL && layout != NULL);
3948 this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
3951 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3953 | elfcpp::SHF_WRITE),
3954 this->got_, false, false, false,
3956 // The old GNU linker creates a .got.plt section. We just
3957 // create another set of data in the .got section. Note that we
3958 // always create a PLT if we create a GOT, although the PLT
3960 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
3961 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3963 | elfcpp::SHF_WRITE),
3964 this->got_plt_, false, false,
3967 // The first three entries are reserved.
3968 this->got_plt_->set_current_data_size(3 * 4);
3970 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3971 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
3972 Symbol_table::PREDEFINED,
3974 0, 0, elfcpp::STT_OBJECT,
3976 elfcpp::STV_HIDDEN, 0,
3982 // Get the dynamic reloc section, creating it if necessary.
3984 template<bool big_endian>
3985 typename Target_arm<big_endian>::Reloc_section*
3986 Target_arm<big_endian>::rel_dyn_section(Layout* layout)
3988 if (this->rel_dyn_ == NULL)
3990 gold_assert(layout != NULL);
3991 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
3992 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
3993 elfcpp::SHF_ALLOC, this->rel_dyn_, true,
3994 false, false, false);
3996 return this->rel_dyn_;
3999 // Insn_template methods.
4001 // Return byte size of an instruction template.
4004 Insn_template::size() const
4006 switch (this->type())
4009 case THUMB16_SPECIAL_TYPE:
4020 // Return alignment of an instruction template.
4023 Insn_template::alignment() const
4025 switch (this->type())
4028 case THUMB16_SPECIAL_TYPE:
4039 // Stub_template methods.
4041 Stub_template::Stub_template(
4042 Stub_type type, const Insn_template* insns,
4044 : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
4045 entry_in_thumb_mode_(false), relocs_()
4049 // Compute byte size and alignment of stub template.
4050 for (size_t i = 0; i < insn_count; i++)
4052 unsigned insn_alignment = insns[i].alignment();
4053 size_t insn_size = insns[i].size();
4054 gold_assert((offset & (insn_alignment - 1)) == 0);
4055 this->alignment_ = std::max(this->alignment_, insn_alignment);
4056 switch (insns[i].type())
4058 case Insn_template::THUMB16_TYPE:
4059 case Insn_template::THUMB16_SPECIAL_TYPE:
4061 this->entry_in_thumb_mode_ = true;
4064 case Insn_template::THUMB32_TYPE:
4065 if (insns[i].r_type() != elfcpp::R_ARM_NONE)
4066 this->relocs_.push_back(Reloc(i, offset));
4068 this->entry_in_thumb_mode_ = true;
4071 case Insn_template::ARM_TYPE:
4072 // Handle cases where the target is encoded within the
4074 if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
4075 this->relocs_.push_back(Reloc(i, offset));
4078 case Insn_template::DATA_TYPE:
4079 // Entry point cannot be data.
4080 gold_assert(i != 0);
4081 this->relocs_.push_back(Reloc(i, offset));
4087 offset += insn_size;
4089 this->size_ = offset;
4094 // Template to implement do_write for a specific target endianity.
4096 template<bool big_endian>
4098 Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
4100 const Stub_template* stub_template = this->stub_template();
4101 const Insn_template* insns = stub_template->insns();
4103 // FIXME: We do not handle BE8 encoding yet.
4104 unsigned char* pov = view;
4105 for (size_t i = 0; i < stub_template->insn_count(); i++)
4107 switch (insns[i].type())
4109 case Insn_template::THUMB16_TYPE:
4110 elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
4112 case Insn_template::THUMB16_SPECIAL_TYPE:
4113 elfcpp::Swap<16, big_endian>::writeval(
4115 this->thumb16_special(i));
4117 case Insn_template::THUMB32_TYPE:
4119 uint32_t hi = (insns[i].data() >> 16) & 0xffff;
4120 uint32_t lo = insns[i].data() & 0xffff;
4121 elfcpp::Swap<16, big_endian>::writeval(pov, hi);
4122 elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
4125 case Insn_template::ARM_TYPE:
4126 case Insn_template::DATA_TYPE:
4127 elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
4132 pov += insns[i].size();
4134 gold_assert(static_cast<section_size_type>(pov - view) == view_size);
4137 // Reloc_stub::Key methods.
4139 // Dump a Key as a string for debugging.
4142 Reloc_stub::Key::name() const
4144 if (this->r_sym_ == invalid_index)
4146 // Global symbol key name
4147 // <stub-type>:<symbol name>:<addend>.
4148 const std::string sym_name = this->u_.symbol->name();
4149 // We need to print two hex number and two colons. So just add 100 bytes
4150 // to the symbol name size.
4151 size_t len = sym_name.size() + 100;
4152 char* buffer = new char[len];
4153 int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
4154 sym_name.c_str(), this->addend_);
4155 gold_assert(c > 0 && c < static_cast<int>(len));
4157 return std::string(buffer);
4161 // local symbol key name
4162 // <stub-type>:<object>:<r_sym>:<addend>.
4163 const size_t len = 200;
4165 int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
4166 this->u_.relobj, this->r_sym_, this->addend_);
4167 gold_assert(c > 0 && c < static_cast<int>(len));
4168 return std::string(buffer);
4172 // Reloc_stub methods.
4174 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
4175 // LOCATION to DESTINATION.
4176 // This code is based on the arm_type_of_stub function in
4177 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
4181 Reloc_stub::stub_type_for_reloc(
4182 unsigned int r_type,
4183 Arm_address location,
4184 Arm_address destination,
4185 bool target_is_thumb)
4187 Stub_type stub_type = arm_stub_none;
4189 // This is a bit ugly but we want to avoid using a templated class for
4190 // big and little endianities.
4192 bool should_force_pic_veneer;
4195 if (parameters->target().is_big_endian())
4197 const Target_arm<true>* big_endian_target =
4198 Target_arm<true>::default_target();
4199 may_use_blx = big_endian_target->may_use_blx();
4200 should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
4201 thumb2 = big_endian_target->using_thumb2();
4202 thumb_only = big_endian_target->using_thumb_only();
4206 const Target_arm<false>* little_endian_target =
4207 Target_arm<false>::default_target();
4208 may_use_blx = little_endian_target->may_use_blx();
4209 should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
4210 thumb2 = little_endian_target->using_thumb2();
4211 thumb_only = little_endian_target->using_thumb_only();
4214 int64_t branch_offset = (int64_t)destination - location;
4216 if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
4218 // Handle cases where:
4219 // - this call goes too far (different Thumb/Thumb2 max
4221 // - it's a Thumb->Arm call and blx is not available, or it's a
4222 // Thumb->Arm branch (not bl). A stub is needed in this case.
4224 && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
4225 || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
4227 && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
4228 || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
4229 || ((!target_is_thumb)
4230 && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
4231 || (r_type == elfcpp::R_ARM_THM_JUMP24))))
4233 if (target_is_thumb)
4238 stub_type = (parameters->options().shared()
4239 || should_force_pic_veneer)
4242 && (r_type == elfcpp::R_ARM_THM_CALL))
4243 // V5T and above. Stub starts with ARM code, so
4244 // we must be able to switch mode before
4245 // reaching it, which is only possible for 'bl'
4246 // (ie R_ARM_THM_CALL relocation).
4247 ? arm_stub_long_branch_any_thumb_pic
4248 // On V4T, use Thumb code only.
4249 : arm_stub_long_branch_v4t_thumb_thumb_pic)
4253 && (r_type == elfcpp::R_ARM_THM_CALL))
4254 ? arm_stub_long_branch_any_any // V5T and above.
4255 : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
4259 stub_type = (parameters->options().shared()
4260 || should_force_pic_veneer)
4261 ? arm_stub_long_branch_thumb_only_pic // PIC stub.
4262 : arm_stub_long_branch_thumb_only; // non-PIC stub.
4269 // FIXME: We should check that the input section is from an
4270 // object that has interwork enabled.
4272 stub_type = (parameters->options().shared()
4273 || should_force_pic_veneer)
4276 && (r_type == elfcpp::R_ARM_THM_CALL))
4277 ? arm_stub_long_branch_any_arm_pic // V5T and above.
4278 : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
4282 && (r_type == elfcpp::R_ARM_THM_CALL))
4283 ? arm_stub_long_branch_any_any // V5T and above.
4284 : arm_stub_long_branch_v4t_thumb_arm); // V4T.
4286 // Handle v4t short branches.
4287 if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
4288 && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
4289 && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
4290 stub_type = arm_stub_short_branch_v4t_thumb_arm;
4294 else if (r_type == elfcpp::R_ARM_CALL
4295 || r_type == elfcpp::R_ARM_JUMP24
4296 || r_type == elfcpp::R_ARM_PLT32)
4298 if (target_is_thumb)
4302 // FIXME: We should check that the input section is from an
4303 // object that has interwork enabled.
4305 // We have an extra 2-bytes reach because of
4306 // the mode change (bit 24 (H) of BLX encoding).
4307 if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
4308 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
4309 || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
4310 || (r_type == elfcpp::R_ARM_JUMP24)
4311 || (r_type == elfcpp::R_ARM_PLT32))
4313 stub_type = (parameters->options().shared()
4314 || should_force_pic_veneer)
4317 ? arm_stub_long_branch_any_thumb_pic// V5T and above.
4318 : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
4322 ? arm_stub_long_branch_any_any // V5T and above.
4323 : arm_stub_long_branch_v4t_arm_thumb); // V4T.
4329 if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
4330 || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
4332 stub_type = (parameters->options().shared()
4333 || should_force_pic_veneer)
4334 ? arm_stub_long_branch_any_arm_pic // PIC stubs.
4335 : arm_stub_long_branch_any_any; /// non-PIC.
4343 // Cortex_a8_stub methods.
4345 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
4346 // I is the position of the instruction template in the stub template.
4349 Cortex_a8_stub::do_thumb16_special(size_t i)
4351 // The only use of this is to copy condition code from a conditional
4352 // branch being worked around to the corresponding conditional branch in
4354 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
4356 uint16_t data = this->stub_template()->insns()[i].data();
4357 gold_assert((data & 0xff00U) == 0xd000U);
4358 data |= ((this->original_insn_ >> 22) & 0xf) << 8;
4362 // Stub_factory methods.
4364 Stub_factory::Stub_factory()
4366 // The instruction template sequences are declared as static
4367 // objects and initialized first time the constructor runs.
4369 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
4370 // to reach the stub if necessary.
4371 static const Insn_template elf32_arm_stub_long_branch_any_any[] =
4373 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4374 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4375 // dcd R_ARM_ABS32(X)
4378 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
4380 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
4382 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4383 Insn_template::arm_insn(0xe12fff1c), // bx ip
4384 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4385 // dcd R_ARM_ABS32(X)
4388 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
4389 static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
4391 Insn_template::thumb16_insn(0xb401), // push {r0}
4392 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4393 Insn_template::thumb16_insn(0x4684), // mov ip, r0
4394 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4395 Insn_template::thumb16_insn(0x4760), // bx ip
4396 Insn_template::thumb16_insn(0xbf00), // nop
4397 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4398 // dcd R_ARM_ABS32(X)
4401 // V4T Thumb -> Thumb long branch stub. Using the stack is not
4403 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
4405 Insn_template::thumb16_insn(0x4778), // bx pc
4406 Insn_template::thumb16_insn(0x46c0), // nop
4407 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4408 Insn_template::arm_insn(0xe12fff1c), // bx ip
4409 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4410 // dcd R_ARM_ABS32(X)
4413 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
4415 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
4417 Insn_template::thumb16_insn(0x4778), // bx pc
4418 Insn_template::thumb16_insn(0x46c0), // nop
4419 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
4420 Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
4421 // dcd R_ARM_ABS32(X)
4424 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
4425 // one, when the destination is close enough.
4426 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
4428 Insn_template::thumb16_insn(0x4778), // bx pc
4429 Insn_template::thumb16_insn(0x46c0), // nop
4430 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
4433 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
4434 // blx to reach the stub if necessary.
4435 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
4437 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
4438 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
4439 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4440 // dcd R_ARM_REL32(X-4)
4443 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
4444 // blx to reach the stub if necessary. We can not add into pc;
4445 // it is not guaranteed to mode switch (different in ARMv6 and
4447 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
4449 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
4450 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4451 Insn_template::arm_insn(0xe12fff1c), // bx ip
4452 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4453 // dcd R_ARM_REL32(X)
4456 // V4T ARM -> ARM long branch stub, PIC.
4457 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
4459 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4460 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4461 Insn_template::arm_insn(0xe12fff1c), // bx ip
4462 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4463 // dcd R_ARM_REL32(X)
4466 // V4T Thumb -> ARM long branch stub, PIC.
4467 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
4469 Insn_template::thumb16_insn(0x4778), // bx pc
4470 Insn_template::thumb16_insn(0x46c0), // nop
4471 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
4472 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
4473 Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
4474 // dcd R_ARM_REL32(X)
4477 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
4479 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
4481 Insn_template::thumb16_insn(0xb401), // push {r0}
4482 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
4483 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
4484 Insn_template::thumb16_insn(0x4484), // add ip, r0
4485 Insn_template::thumb16_insn(0xbc01), // pop {r0}
4486 Insn_template::thumb16_insn(0x4760), // bx ip
4487 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
4488 // dcd R_ARM_REL32(X)
4491 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
4493 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
4495 Insn_template::thumb16_insn(0x4778), // bx pc
4496 Insn_template::thumb16_insn(0x46c0), // nop
4497 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
4498 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
4499 Insn_template::arm_insn(0xe12fff1c), // bx ip
4500 Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
4501 // dcd R_ARM_REL32(X)
4504 // Cortex-A8 erratum-workaround stubs.
4506 // Stub used for conditional branches (which may be beyond +/-1MB away,
4507 // so we can't use a conditional branch to reach this stub).
4514 static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
4516 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
4517 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
4518 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
4522 // Stub used for b.w and bl.w instructions.
4524 static const Insn_template elf32_arm_stub_a8_veneer_b[] =
4526 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4529 static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
4531 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
4534 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
4535 // instruction (which switches to ARM mode) to point to this stub. Jump to
4536 // the real destination using an ARM-mode branch.
4537 static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
4539 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
4542 // Stub used to provide an interworking for R_ARM_V4BX relocation
4543 // (bx r[n] instruction).
4544 static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
4546 Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
4547 Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
4548 Insn_template::arm_insn(0xe12fff10) // bx r<n>
4551 // Fill in the stub template look-up table. Stub templates are constructed
4552 // per instance of Stub_factory for fast look-up without locking
4553 // in a thread-enabled environment.
4555 this->stub_templates_[arm_stub_none] =
4556 new Stub_template(arm_stub_none, NULL, 0);
4558 #define DEF_STUB(x) \
4562 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
4563 Stub_type type = arm_stub_##x; \
4564 this->stub_templates_[type] = \
4565 new Stub_template(type, elf32_arm_stub_##x, array_size); \
4573 // Stub_table methods.
4575 // Removel all Cortex-A8 stub.
4577 template<bool big_endian>
4579 Stub_table<big_endian>::remove_all_cortex_a8_stubs()
4581 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4582 p != this->cortex_a8_stubs_.end();
4585 this->cortex_a8_stubs_.clear();
4588 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
4590 template<bool big_endian>
4592 Stub_table<big_endian>::relocate_stub(
4594 const Relocate_info<32, big_endian>* relinfo,
4595 Target_arm<big_endian>* arm_target,
4596 Output_section* output_section,
4597 unsigned char* view,
4598 Arm_address address,
4599 section_size_type view_size)
4601 const Stub_template* stub_template = stub->stub_template();
4602 if (stub_template->reloc_count() != 0)
4604 // Adjust view to cover the stub only.
4605 section_size_type offset = stub->offset();
4606 section_size_type stub_size = stub_template->size();
4607 gold_assert(offset + stub_size <= view_size);
4609 arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
4610 address + offset, stub_size);
4614 // Relocate all stubs in this stub table.
4616 template<bool big_endian>
4618 Stub_table<big_endian>::relocate_stubs(
4619 const Relocate_info<32, big_endian>* relinfo,
4620 Target_arm<big_endian>* arm_target,
4621 Output_section* output_section,
4622 unsigned char* view,
4623 Arm_address address,
4624 section_size_type view_size)
4626 // If we are passed a view bigger than the stub table's. we need to
4628 gold_assert(address == this->address()
4630 == static_cast<section_size_type>(this->data_size())));
4632 // Relocate all relocation stubs.
4633 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4634 p != this->reloc_stubs_.end();
4636 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4637 address, view_size);
4639 // Relocate all Cortex-A8 stubs.
4640 for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
4641 p != this->cortex_a8_stubs_.end();
4643 this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
4644 address, view_size);
4646 // Relocate all ARM V4BX stubs.
4647 for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
4648 p != this->arm_v4bx_stubs_.end();
4652 this->relocate_stub(*p, relinfo, arm_target, output_section, view,
4653 address, view_size);
4657 // Write out the stubs to file.
4659 template<bool big_endian>
4661 Stub_table<big_endian>::do_write(Output_file* of)
4663 off_t offset = this->offset();
4664 const section_size_type oview_size =
4665 convert_to_section_size_type(this->data_size());
4666 unsigned char* const oview = of->get_output_view(offset, oview_size);
4668 // Write relocation stubs.
4669 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4670 p != this->reloc_stubs_.end();
4673 Reloc_stub* stub = p->second;
4674 Arm_address address = this->address() + stub->offset();
4676 == align_address(address,
4677 stub->stub_template()->alignment()));
4678 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4682 // Write Cortex-A8 stubs.
4683 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4684 p != this->cortex_a8_stubs_.end();
4687 Cortex_a8_stub* stub = p->second;
4688 Arm_address address = this->address() + stub->offset();
4690 == align_address(address,
4691 stub->stub_template()->alignment()));
4692 stub->write(oview + stub->offset(), stub->stub_template()->size(),
4696 // Write ARM V4BX relocation stubs.
4697 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4698 p != this->arm_v4bx_stubs_.end();
4704 Arm_address address = this->address() + (*p)->offset();
4706 == align_address(address,
4707 (*p)->stub_template()->alignment()));
4708 (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
4712 of->write_output_view(this->offset(), oview_size, oview);
4715 // Update the data size and address alignment of the stub table at the end
4716 // of a relaxation pass. Return true if either the data size or the
4717 // alignment changed in this relaxation pass.
4719 template<bool big_endian>
4721 Stub_table<big_endian>::update_data_size_and_addralign()
4724 unsigned addralign = 1;
4726 // Go over all stubs in table to compute data size and address alignment.
4728 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4729 p != this->reloc_stubs_.end();
4732 const Stub_template* stub_template = p->second->stub_template();
4733 addralign = std::max(addralign, stub_template->alignment());
4734 size = (align_address(size, stub_template->alignment())
4735 + stub_template->size());
4738 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4739 p != this->cortex_a8_stubs_.end();
4742 const Stub_template* stub_template = p->second->stub_template();
4743 addralign = std::max(addralign, stub_template->alignment());
4744 size = (align_address(size, stub_template->alignment())
4745 + stub_template->size());
4748 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4749 p != this->arm_v4bx_stubs_.end();
4755 const Stub_template* stub_template = (*p)->stub_template();
4756 addralign = std::max(addralign, stub_template->alignment());
4757 size = (align_address(size, stub_template->alignment())
4758 + stub_template->size());
4761 // Check if either data size or alignment changed in this pass.
4762 // Update prev_data_size_ and prev_addralign_. These will be used
4763 // as the current data size and address alignment for the next pass.
4764 bool changed = size != this->prev_data_size_;
4765 this->prev_data_size_ = size;
4767 if (addralign != this->prev_addralign_)
4769 this->prev_addralign_ = addralign;
4774 // Finalize the stubs. This sets the offsets of the stubs within the stub
4775 // table. It also marks all input sections needing Cortex-A8 workaround.
4777 template<bool big_endian>
4779 Stub_table<big_endian>::finalize_stubs()
4782 for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
4783 p != this->reloc_stubs_.end();
4786 Reloc_stub* stub = p->second;
4787 const Stub_template* stub_template = stub->stub_template();
4788 uint64_t stub_addralign = stub_template->alignment();
4789 off = align_address(off, stub_addralign);
4790 stub->set_offset(off);
4791 off += stub_template->size();
4794 for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
4795 p != this->cortex_a8_stubs_.end();
4798 Cortex_a8_stub* stub = p->second;
4799 const Stub_template* stub_template = stub->stub_template();
4800 uint64_t stub_addralign = stub_template->alignment();
4801 off = align_address(off, stub_addralign);
4802 stub->set_offset(off);
4803 off += stub_template->size();
4805 // Mark input section so that we can determine later if a code section
4806 // needs the Cortex-A8 workaround quickly.
4807 Arm_relobj<big_endian>* arm_relobj =
4808 Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
4809 arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
4812 for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
4813 p != this->arm_v4bx_stubs_.end();
4819 const Stub_template* stub_template = (*p)->stub_template();
4820 uint64_t stub_addralign = stub_template->alignment();
4821 off = align_address(off, stub_addralign);
4822 (*p)->set_offset(off);
4823 off += stub_template->size();
4826 gold_assert(off <= this->prev_data_size_);
4829 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
4830 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
4831 // of the address range seen by the linker.
4833 template<bool big_endian>
4835 Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
4836 Target_arm<big_endian>* arm_target,
4837 unsigned char* view,
4838 Arm_address view_address,
4839 section_size_type view_size)
4841 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
4842 for (Cortex_a8_stub_list::const_iterator p =
4843 this->cortex_a8_stubs_.lower_bound(view_address);
4844 ((p != this->cortex_a8_stubs_.end())
4845 && (p->first < (view_address + view_size)));
4848 // We do not store the THUMB bit in the LSB of either the branch address
4849 // or the stub offset. There is no need to strip the LSB.
4850 Arm_address branch_address = p->first;
4851 const Cortex_a8_stub* stub = p->second;
4852 Arm_address stub_address = this->address() + stub->offset();
4854 // Offset of the branch instruction relative to this view.
4855 section_size_type offset =
4856 convert_to_section_size_type(branch_address - view_address);
4857 gold_assert((offset + 4) <= view_size);
4859 arm_target->apply_cortex_a8_workaround(stub, stub_address,
4860 view + offset, branch_address);
4864 // Arm_input_section methods.
4866 // Initialize an Arm_input_section.
4868 template<bool big_endian>
4870 Arm_input_section<big_endian>::init()
4872 Relobj* relobj = this->relobj();
4873 unsigned int shndx = this->shndx();
4875 // Cache these to speed up size and alignment queries. It is too slow
4876 // to call section_addraglin and section_size every time.
4877 this->original_addralign_ = relobj->section_addralign(shndx);
4878 this->original_size_ = relobj->section_size(shndx);
4880 // We want to make this look like the original input section after
4881 // output sections are finalized.
4882 Output_section* os = relobj->output_section(shndx);
4883 off_t offset = relobj->output_section_offset(shndx);
4884 gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
4885 this->set_address(os->address() + offset);
4886 this->set_file_offset(os->offset() + offset);
4888 this->set_current_data_size(this->original_size_);
4889 this->finalize_data_size();
4892 template<bool big_endian>
4894 Arm_input_section<big_endian>::do_write(Output_file* of)
4896 // We have to write out the original section content.
4897 section_size_type section_size;
4898 const unsigned char* section_contents =
4899 this->relobj()->section_contents(this->shndx(), §ion_size, false);
4900 of->write(this->offset(), section_contents, section_size);
4902 // If this owns a stub table and it is not empty, write it.
4903 if (this->is_stub_table_owner() && !this->stub_table_->empty())
4904 this->stub_table_->write(of);
4907 // Finalize data size.
4909 template<bool big_endian>
4911 Arm_input_section<big_endian>::set_final_data_size()
4913 // If this owns a stub table, finalize its data size as well.
4914 if (this->is_stub_table_owner())
4916 uint64_t address = this->address();
4918 // The stub table comes after the original section contents.
4919 address += this->original_size_;
4920 address = align_address(address, this->stub_table_->addralign());
4921 off_t offset = this->offset() + (address - this->address());
4922 this->stub_table_->set_address_and_file_offset(address, offset);
4923 address += this->stub_table_->data_size();
4924 gold_assert(address == this->address() + this->current_data_size());
4927 this->set_data_size(this->current_data_size());
4930 // Reset address and file offset.
4932 template<bool big_endian>
4934 Arm_input_section<big_endian>::do_reset_address_and_file_offset()
4936 // Size of the original input section contents.
4937 off_t off = convert_types<off_t, uint64_t>(this->original_size_);
4939 // If this is a stub table owner, account for the stub table size.
4940 if (this->is_stub_table_owner())
4942 Stub_table<big_endian>* stub_table = this->stub_table_;
4944 // Reset the stub table's address and file offset. The
4945 // current data size for child will be updated after that.
4946 stub_table_->reset_address_and_file_offset();
4947 off = align_address(off, stub_table_->addralign());
4948 off += stub_table->current_data_size();
4951 this->set_current_data_size(off);
4954 // Arm_exidx_cantunwind methods.
4956 // Write this to Output file OF for a fixed endianity.
4958 template<bool big_endian>
4960 Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
4962 off_t offset = this->offset();
4963 const section_size_type oview_size = 8;
4964 unsigned char* const oview = of->get_output_view(offset, oview_size);
4966 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
4967 Valtype* wv = reinterpret_cast<Valtype*>(oview);
4969 Output_section* os = this->relobj_->output_section(this->shndx_);
4970 gold_assert(os != NULL);
4972 Arm_relobj<big_endian>* arm_relobj =
4973 Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
4974 Arm_address output_offset =
4975 arm_relobj->get_output_section_offset(this->shndx_);
4976 Arm_address section_start;
4977 if(output_offset != Arm_relobj<big_endian>::invalid_address)
4978 section_start = os->address() + output_offset;
4981 // Currently this only happens for a relaxed section.
4982 const Output_relaxed_input_section* poris =
4983 os->find_relaxed_input_section(this->relobj_, this->shndx_);
4984 gold_assert(poris != NULL);
4985 section_start = poris->address();
4988 // We always append this to the end of an EXIDX section.
4989 Arm_address output_address =
4990 section_start + this->relobj_->section_size(this->shndx_);
4992 // Write out the entry. The first word either points to the beginning
4993 // or after the end of a text section. The second word is the special
4994 // EXIDX_CANTUNWIND value.
4995 uint32_t prel31_offset = output_address - this->address();
4996 if (utils::has_overflow<31>(offset))
4997 gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
4998 elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
4999 elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
5001 of->write_output_view(this->offset(), oview_size, oview);
5004 // Arm_exidx_merged_section methods.
5006 // Constructor for Arm_exidx_merged_section.
5007 // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
5008 // SECTION_OFFSET_MAP points to a section offset map describing how
5009 // parts of the input section are mapped to output. DELETED_BYTES is
5010 // the number of bytes deleted from the EXIDX input section.
5012 Arm_exidx_merged_section::Arm_exidx_merged_section(
5013 const Arm_exidx_input_section& exidx_input_section,
5014 const Arm_exidx_section_offset_map& section_offset_map,
5015 uint32_t deleted_bytes)
5016 : Output_relaxed_input_section(exidx_input_section.relobj(),
5017 exidx_input_section.shndx(),
5018 exidx_input_section.addralign()),
5019 exidx_input_section_(exidx_input_section),
5020 section_offset_map_(section_offset_map)
5022 // Fix size here so that we do not need to implement set_final_data_size.
5023 this->set_data_size(exidx_input_section.size() - deleted_bytes);
5024 this->fix_data_size();
5027 // Given an input OBJECT, an input section index SHNDX within that
5028 // object, and an OFFSET relative to the start of that input
5029 // section, return whether or not the corresponding offset within
5030 // the output section is known. If this function returns true, it
5031 // sets *POUTPUT to the output offset. The value -1 indicates that
5032 // this input offset is being discarded.
5035 Arm_exidx_merged_section::do_output_offset(
5036 const Relobj* relobj,
5038 section_offset_type offset,
5039 section_offset_type* poutput) const
5041 // We only handle offsets for the original EXIDX input section.
5042 if (relobj != this->exidx_input_section_.relobj()
5043 || shndx != this->exidx_input_section_.shndx())
5046 section_offset_type section_size =
5047 convert_types<section_offset_type>(this->exidx_input_section_.size());
5048 if (offset < 0 || offset >= section_size)
5049 // Input offset is out of valid range.
5053 // We need to look up the section offset map to determine the output
5054 // offset. Find the reference point in map that is first offset
5055 // bigger than or equal to this offset.
5056 Arm_exidx_section_offset_map::const_iterator p =
5057 this->section_offset_map_.lower_bound(offset);
5059 // The section offset maps are build such that this should not happen if
5060 // input offset is in the valid range.
5061 gold_assert(p != this->section_offset_map_.end());
5063 // We need to check if this is dropped.
5064 section_offset_type ref = p->first;
5065 section_offset_type mapped_ref = p->second;
5067 if (mapped_ref != Arm_exidx_input_section::invalid_offset)
5068 // Offset is present in output.
5069 *poutput = mapped_ref + (offset - ref);
5071 // Offset is discarded owing to EXIDX entry merging.
5078 // Write this to output file OF.
5081 Arm_exidx_merged_section::do_write(Output_file* of)
5083 // If we retain or discard the whole EXIDX input section, we would
5085 gold_assert(this->data_size() != this->exidx_input_section_.size()
5086 && this->data_size() != 0);
5088 off_t offset = this->offset();
5089 const section_size_type oview_size = this->data_size();
5090 unsigned char* const oview = of->get_output_view(offset, oview_size);
5092 Output_section* os = this->relobj()->output_section(this->shndx());
5093 gold_assert(os != NULL);
5095 // Get contents of EXIDX input section.
5096 section_size_type section_size;
5097 const unsigned char* section_contents =
5098 this->relobj()->section_contents(this->shndx(), §ion_size, false);
5099 gold_assert(section_size == this->exidx_input_section_.size());
5101 // Go over spans of input offsets and write only those that are not
5103 section_offset_type in_start = 0;
5104 section_offset_type out_start = 0;
5105 for(Arm_exidx_section_offset_map::const_iterator p =
5106 this->section_offset_map_.begin();
5107 p != this->section_offset_map_.end();
5110 section_offset_type in_end = p->first;
5111 gold_assert(in_end >= in_start);
5112 section_offset_type out_end = p->second;
5113 size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
5116 size_t out_chunk_size =
5117 convert_types<size_t>(out_end - out_start + 1);
5118 gold_assert(out_chunk_size == in_chunk_size);
5119 memcpy(oview + out_start, section_contents + in_start,
5121 out_start += out_chunk_size;
5123 in_start += in_chunk_size;
5126 gold_assert(convert_to_section_size_type(out_start) == oview_size);
5127 of->write_output_view(this->offset(), oview_size, oview);
5130 // Arm_exidx_fixup methods.
5132 // Append an EXIDX_CANTUNWIND in the current output section if the last entry
5133 // is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
5134 // points to the end of the last seen EXIDX section.
5137 Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
5139 if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
5140 && this->last_input_section_ != NULL)
5142 Relobj* relobj = this->last_input_section_->relobj();
5143 unsigned int text_shndx = this->last_input_section_->link();
5144 Arm_exidx_cantunwind* cantunwind =
5145 new Arm_exidx_cantunwind(relobj, text_shndx);
5146 this->exidx_output_section_->add_output_section_data(cantunwind);
5147 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5151 // Process an EXIDX section entry in input. Return whether this entry
5152 // can be deleted in the output. SECOND_WORD in the second word of the
5156 Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
5159 if (second_word == elfcpp::EXIDX_CANTUNWIND)
5161 // Merge if previous entry is also an EXIDX_CANTUNWIND.
5162 delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
5163 this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
5165 else if ((second_word & 0x80000000) != 0)
5167 // Inlined unwinding data. Merge if equal to previous.
5168 delete_entry = (this->last_unwind_type_ == UT_INLINED_ENTRY
5169 && this->last_inlined_entry_ == second_word);
5170 this->last_unwind_type_ = UT_INLINED_ENTRY;
5171 this->last_inlined_entry_ = second_word;
5175 // Normal table entry. In theory we could merge these too,
5176 // but duplicate entries are likely to be much less common.
5177 delete_entry = false;
5178 this->last_unwind_type_ = UT_NORMAL_ENTRY;
5180 return delete_entry;
5183 // Update the current section offset map during EXIDX section fix-up.
5184 // If there is no map, create one. INPUT_OFFSET is the offset of a
5185 // reference point, DELETED_BYTES is the number of deleted by in the
5186 // section so far. If DELETE_ENTRY is true, the reference point and
5187 // all offsets after the previous reference point are discarded.
5190 Arm_exidx_fixup::update_offset_map(
5191 section_offset_type input_offset,
5192 section_size_type deleted_bytes,
5195 if (this->section_offset_map_ == NULL)
5196 this->section_offset_map_ = new Arm_exidx_section_offset_map();
5197 section_offset_type output_offset =
5199 ? Arm_exidx_input_section::invalid_offset
5200 : input_offset - deleted_bytes);
5201 (*this->section_offset_map_)[input_offset] = output_offset;
5204 // Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
5205 // bytes deleted. If some entries are merged, also store a pointer to a newly
5206 // created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
5207 // caller owns the map and is responsible for releasing it after use.
5209 template<bool big_endian>
5211 Arm_exidx_fixup::process_exidx_section(
5212 const Arm_exidx_input_section* exidx_input_section,
5213 Arm_exidx_section_offset_map** psection_offset_map)
5215 Relobj* relobj = exidx_input_section->relobj();
5216 unsigned shndx = exidx_input_section->shndx();
5217 section_size_type section_size;
5218 const unsigned char* section_contents =
5219 relobj->section_contents(shndx, §ion_size, false);
5221 if ((section_size % 8) != 0)
5223 // Something is wrong with this section. Better not touch it.
5224 gold_error(_("uneven .ARM.exidx section size in %s section %u"),
5225 relobj->name().c_str(), shndx);
5226 this->last_input_section_ = exidx_input_section;
5227 this->last_unwind_type_ = UT_NONE;
5231 uint32_t deleted_bytes = 0;
5232 bool prev_delete_entry = false;
5233 gold_assert(this->section_offset_map_ == NULL);
5235 for (section_size_type i = 0; i < section_size; i += 8)
5237 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
5239 reinterpret_cast<const Valtype*>(section_contents + i + 4);
5240 uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
5242 bool delete_entry = this->process_exidx_entry(second_word);
5244 // Entry deletion causes changes in output offsets. We use a std::map
5245 // to record these. And entry (x, y) means input offset x
5246 // is mapped to output offset y. If y is invalid_offset, then x is
5247 // dropped in the output. Because of the way std::map::lower_bound
5248 // works, we record the last offset in a region w.r.t to keeping or
5249 // dropping. If there is no entry (x0, y0) for an input offset x0,
5250 // the output offset y0 of it is determined by the output offset y1 of
5251 // the smallest input offset x1 > x0 that there is an (x1, y1) entry
5252 // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
5254 if (delete_entry != prev_delete_entry && i != 0)
5255 this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
5257 // Update total deleted bytes for this entry.
5261 prev_delete_entry = delete_entry;
5264 // If section offset map is not NULL, make an entry for the end of
5266 if (this->section_offset_map_ != NULL)
5267 update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
5269 *psection_offset_map = this->section_offset_map_;
5270 this->section_offset_map_ = NULL;
5271 this->last_input_section_ = exidx_input_section;
5273 // Set the first output text section so that we can link the EXIDX output
5274 // section to it. Ignore any EXIDX input section that is completely merged.
5275 if (this->first_output_text_section_ == NULL
5276 && deleted_bytes != section_size)
5278 unsigned int link = exidx_input_section->link();
5279 Output_section* os = relobj->output_section(link);
5280 gold_assert(os != NULL);
5281 this->first_output_text_section_ = os;
5284 return deleted_bytes;
5287 // Arm_output_section methods.
5289 // Create a stub group for input sections from BEGIN to END. OWNER
5290 // points to the input section to be the owner a new stub table.
5292 template<bool big_endian>
5294 Arm_output_section<big_endian>::create_stub_group(
5295 Input_section_list::const_iterator begin,
5296 Input_section_list::const_iterator end,
5297 Input_section_list::const_iterator owner,
5298 Target_arm<big_endian>* target,
5299 std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
5301 // We use a different kind of relaxed section in an EXIDX section.
5302 // The static casting from Output_relaxed_input_section to
5303 // Arm_input_section is invalid in an EXIDX section. We are okay
5304 // because we should not be calling this for an EXIDX section.
5305 gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
5307 // Currently we convert ordinary input sections into relaxed sections only
5308 // at this point but we may want to support creating relaxed input section
5309 // very early. So we check here to see if owner is already a relaxed
5312 Arm_input_section<big_endian>* arm_input_section;
5313 if (owner->is_relaxed_input_section())
5316 Arm_input_section<big_endian>::as_arm_input_section(
5317 owner->relaxed_input_section());
5321 gold_assert(owner->is_input_section());
5322 // Create a new relaxed input section.
5324 target->new_arm_input_section(owner->relobj(), owner->shndx());
5325 new_relaxed_sections->push_back(arm_input_section);
5328 // Create a stub table.
5329 Stub_table<big_endian>* stub_table =
5330 target->new_stub_table(arm_input_section);
5332 arm_input_section->set_stub_table(stub_table);
5334 Input_section_list::const_iterator p = begin;
5335 Input_section_list::const_iterator prev_p;
5337 // Look for input sections or relaxed input sections in [begin ... end].
5340 if (p->is_input_section() || p->is_relaxed_input_section())
5342 // The stub table information for input sections live
5343 // in their objects.
5344 Arm_relobj<big_endian>* arm_relobj =
5345 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5346 arm_relobj->set_stub_table(p->shndx(), stub_table);
5350 while (prev_p != end);
5353 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
5354 // of stub groups. We grow a stub group by adding input section until the
5355 // size is just below GROUP_SIZE. The last input section will be converted
5356 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
5357 // input section after the stub table, effectively double the group size.
5359 // This is similar to the group_sections() function in elf32-arm.c but is
5360 // implemented differently.
5362 template<bool big_endian>
5364 Arm_output_section<big_endian>::group_sections(
5365 section_size_type group_size,
5366 bool stubs_always_after_branch,
5367 Target_arm<big_endian>* target)
5369 // We only care about sections containing code.
5370 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5373 // States for grouping.
5376 // No group is being built.
5378 // A group is being built but the stub table is not found yet.
5379 // We keep group a stub group until the size is just under GROUP_SIZE.
5380 // The last input section in the group will be used as the stub table.
5381 FINDING_STUB_SECTION,
5382 // A group is being built and we have already found a stub table.
5383 // We enter this state to grow a stub group by adding input section
5384 // after the stub table. This effectively doubles the group size.
5388 // Any newly created relaxed sections are stored here.
5389 std::vector<Output_relaxed_input_section*> new_relaxed_sections;
5391 State state = NO_GROUP;
5392 section_size_type off = 0;
5393 section_size_type group_begin_offset = 0;
5394 section_size_type group_end_offset = 0;
5395 section_size_type stub_table_end_offset = 0;
5396 Input_section_list::const_iterator group_begin =
5397 this->input_sections().end();
5398 Input_section_list::const_iterator stub_table =
5399 this->input_sections().end();
5400 Input_section_list::const_iterator group_end = this->input_sections().end();
5401 for (Input_section_list::const_iterator p = this->input_sections().begin();
5402 p != this->input_sections().end();
5405 section_size_type section_begin_offset =
5406 align_address(off, p->addralign());
5407 section_size_type section_end_offset =
5408 section_begin_offset + p->data_size();
5410 // Check to see if we should group the previously seens sections.
5416 case FINDING_STUB_SECTION:
5417 // Adding this section makes the group larger than GROUP_SIZE.
5418 if (section_end_offset - group_begin_offset >= group_size)
5420 if (stubs_always_after_branch)
5422 gold_assert(group_end != this->input_sections().end());
5423 this->create_stub_group(group_begin, group_end, group_end,
5424 target, &new_relaxed_sections);
5429 // But wait, there's more! Input sections up to
5430 // stub_group_size bytes after the stub table can be
5431 // handled by it too.
5432 state = HAS_STUB_SECTION;
5433 stub_table = group_end;
5434 stub_table_end_offset = group_end_offset;
5439 case HAS_STUB_SECTION:
5440 // Adding this section makes the post stub-section group larger
5442 if (section_end_offset - stub_table_end_offset >= group_size)
5444 gold_assert(group_end != this->input_sections().end());
5445 this->create_stub_group(group_begin, group_end, stub_table,
5446 target, &new_relaxed_sections);
5455 // If we see an input section and currently there is no group, start
5456 // a new one. Skip any empty sections.
5457 if ((p->is_input_section() || p->is_relaxed_input_section())
5458 && (p->relobj()->section_size(p->shndx()) != 0))
5460 if (state == NO_GROUP)
5462 state = FINDING_STUB_SECTION;
5464 group_begin_offset = section_begin_offset;
5467 // Keep track of the last input section seen.
5469 group_end_offset = section_end_offset;
5472 off = section_end_offset;
5475 // Create a stub group for any ungrouped sections.
5476 if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
5478 gold_assert(group_end != this->input_sections().end());
5479 this->create_stub_group(group_begin, group_end,
5480 (state == FINDING_STUB_SECTION
5483 target, &new_relaxed_sections);
5486 // Convert input section into relaxed input section in a batch.
5487 if (!new_relaxed_sections.empty())
5488 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
5490 // Update the section offsets
5491 for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
5493 Arm_relobj<big_endian>* arm_relobj =
5494 Arm_relobj<big_endian>::as_arm_relobj(
5495 new_relaxed_sections[i]->relobj());
5496 unsigned int shndx = new_relaxed_sections[i]->shndx();
5497 // Tell Arm_relobj that this input section is converted.
5498 arm_relobj->convert_input_section_to_relaxed_section(shndx);
5502 // Append non empty text sections in this to LIST in ascending
5503 // order of their position in this.
5505 template<bool big_endian>
5507 Arm_output_section<big_endian>::append_text_sections_to_list(
5508 Text_section_list* list)
5510 // We only care about text sections.
5511 if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
5514 gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
5516 for (Input_section_list::const_iterator p = this->input_sections().begin();
5517 p != this->input_sections().end();
5520 // We only care about plain or relaxed input sections. We also
5521 // ignore any merged sections.
5522 if ((p->is_input_section() || p->is_relaxed_input_section())
5523 && p->data_size() != 0)
5524 list->push_back(Text_section_list::value_type(p->relobj(),
5529 template<bool big_endian>
5531 Arm_output_section<big_endian>::fix_exidx_coverage(
5533 const Text_section_list& sorted_text_sections,
5534 Symbol_table* symtab)
5536 // We should only do this for the EXIDX output section.
5537 gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
5539 // We don't want the relaxation loop to undo these changes, so we discard
5540 // the current saved states and take another one after the fix-up.
5541 this->discard_states();
5543 // Remove all input sections.
5544 uint64_t address = this->address();
5545 typedef std::list<Simple_input_section> Simple_input_section_list;
5546 Simple_input_section_list input_sections;
5547 this->reset_address_and_file_offset();
5548 this->get_input_sections(address, std::string(""), &input_sections);
5550 if (!this->input_sections().empty())
5551 gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
5553 // Go through all the known input sections and record them.
5554 typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
5555 Section_id_set known_input_sections;
5556 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5557 p != input_sections.end();
5560 // This should never happen. At this point, we should only see
5561 // plain EXIDX input sections.
5562 gold_assert(!p->is_relaxed_input_section());
5563 known_input_sections.insert(Section_id(p->relobj(), p->shndx()));
5566 Arm_exidx_fixup exidx_fixup(this);
5568 // Go over the sorted text sections.
5569 Section_id_set processed_input_sections;
5570 for (Text_section_list::const_iterator p = sorted_text_sections.begin();
5571 p != sorted_text_sections.end();
5574 Relobj* relobj = p->first;
5575 unsigned int shndx = p->second;
5577 Arm_relobj<big_endian>* arm_relobj =
5578 Arm_relobj<big_endian>::as_arm_relobj(relobj);
5579 const Arm_exidx_input_section* exidx_input_section =
5580 arm_relobj->exidx_input_section_by_link(shndx);
5582 // If this text section has no EXIDX section, force an EXIDX_CANTUNWIND
5583 // entry pointing to the end of the last seen EXIDX section.
5584 if (exidx_input_section == NULL)
5586 exidx_fixup.add_exidx_cantunwind_as_needed();
5590 Relobj* exidx_relobj = exidx_input_section->relobj();
5591 unsigned int exidx_shndx = exidx_input_section->shndx();
5592 Section_id sid(exidx_relobj, exidx_shndx);
5593 if (known_input_sections.find(sid) == known_input_sections.end())
5595 // This is odd. We have not seen this EXIDX input section before.
5596 // We cannot do fix-up. If we saw a SECTIONS clause in a script,
5597 // issue a warning instead. We assume the user knows what he
5598 // or she is doing. Otherwise, this is an error.
5599 if (layout->script_options()->saw_sections_clause())
5600 gold_warning(_("unwinding may not work because EXIDX input section"
5601 " %u of %s is not in EXIDX output section"),
5602 exidx_shndx, exidx_relobj->name().c_str());
5604 gold_error(_("unwinding may not work because EXIDX input section"
5605 " %u of %s is not in EXIDX output section"),
5606 exidx_shndx, exidx_relobj->name().c_str());
5608 exidx_fixup.add_exidx_cantunwind_as_needed();
5612 // Fix up coverage and append input section to output data list.
5613 Arm_exidx_section_offset_map* section_offset_map = NULL;
5614 uint32_t deleted_bytes =
5615 exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
5616 §ion_offset_map);
5618 if (deleted_bytes == exidx_input_section->size())
5620 // The whole EXIDX section got merged. Remove it from output.
5621 gold_assert(section_offset_map == NULL);
5622 exidx_relobj->set_output_section(exidx_shndx, NULL);
5624 // All local symbols defined in this input section will be dropped.
5625 // We need to adjust output local symbol count.
5626 arm_relobj->set_output_local_symbol_count_needs_update();
5628 else if (deleted_bytes > 0)
5630 // Some entries are merged. We need to convert this EXIDX input
5631 // section into a relaxed section.
5632 gold_assert(section_offset_map != NULL);
5633 Arm_exidx_merged_section* merged_section =
5634 new Arm_exidx_merged_section(*exidx_input_section,
5635 *section_offset_map, deleted_bytes);
5636 this->add_relaxed_input_section(merged_section);
5637 arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
5639 // All local symbols defined in discarded portions of this input
5640 // section will be dropped. We need to adjust output local symbol
5642 arm_relobj->set_output_local_symbol_count_needs_update();
5646 // Just add back the EXIDX input section.
5647 gold_assert(section_offset_map == NULL);
5648 Output_section::Simple_input_section sis(exidx_relobj, exidx_shndx);
5649 this->add_simple_input_section(sis, exidx_input_section->size(),
5650 exidx_input_section->addralign());
5653 processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
5656 // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
5657 exidx_fixup.add_exidx_cantunwind_as_needed();
5659 // Remove any known EXIDX input sections that are not processed.
5660 for (Simple_input_section_list::const_iterator p = input_sections.begin();
5661 p != input_sections.end();
5664 if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
5665 == processed_input_sections.end())
5667 // We only discard a known EXIDX section because its linked
5668 // text section has been folded by ICF.
5669 Arm_relobj<big_endian>* arm_relobj =
5670 Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
5671 const Arm_exidx_input_section* exidx_input_section =
5672 arm_relobj->exidx_input_section_by_shndx(p->shndx());
5673 gold_assert(exidx_input_section != NULL);
5674 unsigned int text_shndx = exidx_input_section->link();
5675 gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
5677 // Remove this from link.
5678 p->relobj()->set_output_section(p->shndx(), NULL);
5682 // Link exidx output section to the first seen output section and
5683 // set correct entry size.
5684 this->set_link_section(exidx_fixup.first_output_text_section());
5685 this->set_entsize(8);
5687 // Make changes permanent.
5688 this->save_states();
5689 this->set_section_offsets_need_adjustment();
5692 // Arm_relobj methods.
5694 // Determine if an input section is scannable for stub processing. SHDR is
5695 // the header of the section and SHNDX is the section index. OS is the output
5696 // section for the input section and SYMTAB is the global symbol table used to
5697 // look up ICF information.
5699 template<bool big_endian>
5701 Arm_relobj<big_endian>::section_is_scannable(
5702 const elfcpp::Shdr<32, big_endian>& shdr,
5704 const Output_section* os,
5705 const Symbol_table *symtab)
5707 // Skip any empty sections, unallocated sections or sections whose
5708 // type are not SHT_PROGBITS.
5709 if (shdr.get_sh_size() == 0
5710 || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
5711 || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
5714 // Skip any discarded or ICF'ed sections.
5715 if (os == NULL || symtab->is_section_folded(this, shndx))
5718 // If this requires special offset handling, check to see if it is
5719 // a relaxed section. If this is not, then it is a merged section that
5720 // we cannot handle.
5721 if (this->is_output_section_offset_invalid(shndx))
5723 const Output_relaxed_input_section* poris =
5724 os->find_relaxed_input_section(this, shndx);
5732 // Determine if we want to scan the SHNDX-th section for relocation stubs.
5733 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5735 template<bool big_endian>
5737 Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
5738 const elfcpp::Shdr<32, big_endian>& shdr,
5739 const Relobj::Output_sections& out_sections,
5740 const Symbol_table *symtab,
5741 const unsigned char* pshdrs)
5743 unsigned int sh_type = shdr.get_sh_type();
5744 if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
5747 // Ignore empty section.
5748 off_t sh_size = shdr.get_sh_size();
5752 // Ignore reloc section with unexpected symbol table. The
5753 // error will be reported in the final link.
5754 if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
5757 unsigned int reloc_size;
5758 if (sh_type == elfcpp::SHT_REL)
5759 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5761 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5763 // Ignore reloc section with unexpected entsize or uneven size.
5764 // The error will be reported in the final link.
5765 if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
5768 // Ignore reloc section with bad info. This error will be
5769 // reported in the final link.
5770 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5771 if (index >= this->shnum())
5774 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5775 const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
5776 return this->section_is_scannable(text_shdr, index,
5777 out_sections[index], symtab);
5780 // Return the output address of either a plain input section or a relaxed
5781 // input section. SHNDX is the section index. We define and use this
5782 // instead of calling Output_section::output_address because that is slow
5783 // for large output.
5785 template<bool big_endian>
5787 Arm_relobj<big_endian>::simple_input_section_output_address(
5791 if (this->is_output_section_offset_invalid(shndx))
5793 const Output_relaxed_input_section* poris =
5794 os->find_relaxed_input_section(this, shndx);
5795 // We do not handle merged sections here.
5796 gold_assert(poris != NULL);
5797 return poris->address();
5800 return os->address() + this->get_output_section_offset(shndx);
5803 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
5804 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
5806 template<bool big_endian>
5808 Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
5809 const elfcpp::Shdr<32, big_endian>& shdr,
5812 const Symbol_table* symtab)
5814 if (!this->section_is_scannable(shdr, shndx, os, symtab))
5817 // If the section does not cross any 4K-boundaries, it does not need to
5819 Arm_address address = this->simple_input_section_output_address(shndx, os);
5820 if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
5826 // Scan a section for Cortex-A8 workaround.
5828 template<bool big_endian>
5830 Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
5831 const elfcpp::Shdr<32, big_endian>& shdr,
5834 Target_arm<big_endian>* arm_target)
5836 // Look for the first mapping symbol in this section. It should be
5838 Mapping_symbol_position section_start(shndx, 0);
5839 typename Mapping_symbols_info::const_iterator p =
5840 this->mapping_symbols_info_.lower_bound(section_start);
5842 // There are no mapping symbols for this section. Treat it as a data-only
5844 if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
5847 Arm_address output_address =
5848 this->simple_input_section_output_address(shndx, os);
5850 // Get the section contents.
5851 section_size_type input_view_size = 0;
5852 const unsigned char* input_view =
5853 this->section_contents(shndx, &input_view_size, false);
5855 // We need to go through the mapping symbols to determine what to
5856 // scan. There are two reasons. First, we should look at THUMB code and
5857 // THUMB code only. Second, we only want to look at the 4K-page boundary
5858 // to speed up the scanning.
5860 while (p != this->mapping_symbols_info_.end()
5861 && p->first.first == shndx)
5863 typename Mapping_symbols_info::const_iterator next =
5864 this->mapping_symbols_info_.upper_bound(p->first);
5866 // Only scan part of a section with THUMB code.
5867 if (p->second == 't')
5869 // Determine the end of this range.
5870 section_size_type span_start =
5871 convert_to_section_size_type(p->first.second);
5872 section_size_type span_end;
5873 if (next != this->mapping_symbols_info_.end()
5874 && next->first.first == shndx)
5875 span_end = convert_to_section_size_type(next->first.second);
5877 span_end = convert_to_section_size_type(shdr.get_sh_size());
5879 if (((span_start + output_address) & ~0xfffUL)
5880 != ((span_end + output_address - 1) & ~0xfffUL))
5882 arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
5883 span_start, span_end,
5893 // Scan relocations for stub generation.
5895 template<bool big_endian>
5897 Arm_relobj<big_endian>::scan_sections_for_stubs(
5898 Target_arm<big_endian>* arm_target,
5899 const Symbol_table* symtab,
5900 const Layout* layout)
5902 unsigned int shnum = this->shnum();
5903 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
5905 // Read the section headers.
5906 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
5910 // To speed up processing, we set up hash tables for fast lookup of
5911 // input offsets to output addresses.
5912 this->initialize_input_to_output_maps();
5914 const Relobj::Output_sections& out_sections(this->output_sections());
5916 Relocate_info<32, big_endian> relinfo;
5917 relinfo.symtab = symtab;
5918 relinfo.layout = layout;
5919 relinfo.object = this;
5921 // Do relocation stubs scanning.
5922 const unsigned char* p = pshdrs + shdr_size;
5923 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
5925 const elfcpp::Shdr<32, big_endian> shdr(p);
5926 if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
5929 unsigned int index = this->adjust_shndx(shdr.get_sh_info());
5930 Arm_address output_offset = this->get_output_section_offset(index);
5931 Arm_address output_address;
5932 if(output_offset != invalid_address)
5933 output_address = out_sections[index]->address() + output_offset;
5936 // Currently this only happens for a relaxed section.
5937 const Output_relaxed_input_section* poris =
5938 out_sections[index]->find_relaxed_input_section(this, index);
5939 gold_assert(poris != NULL);
5940 output_address = poris->address();
5943 // Get the relocations.
5944 const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
5948 // Get the section contents. This does work for the case in which
5949 // we modify the contents of an input section. We need to pass the
5950 // output view under such circumstances.
5951 section_size_type input_view_size = 0;
5952 const unsigned char* input_view =
5953 this->section_contents(index, &input_view_size, false);
5955 relinfo.reloc_shndx = i;
5956 relinfo.data_shndx = index;
5957 unsigned int sh_type = shdr.get_sh_type();
5958 unsigned int reloc_size;
5959 if (sh_type == elfcpp::SHT_REL)
5960 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
5962 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
5964 Output_section* os = out_sections[index];
5965 arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
5966 shdr.get_sh_size() / reloc_size,
5968 output_offset == invalid_address,
5969 input_view, output_address,
5974 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
5975 // after its relocation section, if there is one, is processed for
5976 // relocation stubs. Merging this loop with the one above would have been
5977 // complicated since we would have had to make sure that relocation stub
5978 // scanning is done first.
5979 if (arm_target->fix_cortex_a8())
5981 const unsigned char* p = pshdrs + shdr_size;
5982 for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
5984 const elfcpp::Shdr<32, big_endian> shdr(p);
5985 if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
5988 this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
5993 // After we've done the relocations, we release the hash tables,
5994 // since we no longer need them.
5995 this->free_input_to_output_maps();
5998 // Count the local symbols. The ARM backend needs to know if a symbol
5999 // is a THUMB function or not. For global symbols, it is easy because
6000 // the Symbol object keeps the ELF symbol type. For local symbol it is
6001 // harder because we cannot access this information. So we override the
6002 // do_count_local_symbol in parent and scan local symbols to mark
6003 // THUMB functions. This is not the most efficient way but I do not want to
6004 // slow down other ports by calling a per symbol targer hook inside
6005 // Sized_relobj<size, big_endian>::do_count_local_symbols.
6007 template<bool big_endian>
6009 Arm_relobj<big_endian>::do_count_local_symbols(
6010 Stringpool_template<char>* pool,
6011 Stringpool_template<char>* dynpool)
6013 // We need to fix-up the values of any local symbols whose type are
6016 // Ask parent to count the local symbols.
6017 Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
6018 const unsigned int loccount = this->local_symbol_count();
6022 // Intialize the thumb function bit-vector.
6023 std::vector<bool> empty_vector(loccount, false);
6024 this->local_symbol_is_thumb_function_.swap(empty_vector);
6026 // Read the symbol table section header.
6027 const unsigned int symtab_shndx = this->symtab_shndx();
6028 elfcpp::Shdr<32, big_endian>
6029 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6030 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6032 // Read the local symbols.
6033 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6034 gold_assert(loccount == symtabshdr.get_sh_info());
6035 off_t locsize = loccount * sym_size;
6036 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6037 locsize, true, true);
6039 // For mapping symbol processing, we need to read the symbol names.
6040 unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
6041 if (strtab_shndx >= this->shnum())
6043 this->error(_("invalid symbol table name index: %u"), strtab_shndx);
6047 elfcpp::Shdr<32, big_endian>
6048 strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
6049 if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
6051 this->error(_("symbol table name section has wrong type: %u"),
6052 static_cast<unsigned int>(strtabshdr.get_sh_type()));
6055 const char* pnames =
6056 reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
6057 strtabshdr.get_sh_size(),
6060 // Loop over the local symbols and mark any local symbols pointing
6061 // to THUMB functions.
6063 // Skip the first dummy symbol.
6065 typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
6066 this->local_values();
6067 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6069 elfcpp::Sym<32, big_endian> sym(psyms);
6070 elfcpp::STT st_type = sym.get_st_type();
6071 Symbol_value<32>& lv((*plocal_values)[i]);
6072 Arm_address input_value = lv.input_value();
6074 // Check to see if this is a mapping symbol.
6075 const char* sym_name = pnames + sym.get_st_name();
6076 if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
6078 unsigned int input_shndx = sym.get_st_shndx();
6080 // Strip of LSB in case this is a THUMB symbol.
6081 Mapping_symbol_position msp(input_shndx, input_value & ~1U);
6082 this->mapping_symbols_info_[msp] = sym_name[1];
6085 if (st_type == elfcpp::STT_ARM_TFUNC
6086 || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
6088 // This is a THUMB function. Mark this and canonicalize the
6089 // symbol value by setting LSB.
6090 this->local_symbol_is_thumb_function_[i] = true;
6091 if ((input_value & 1) == 0)
6092 lv.set_input_value(input_value | 1);
6097 // Relocate sections.
6098 template<bool big_endian>
6100 Arm_relobj<big_endian>::do_relocate_sections(
6101 const Symbol_table* symtab,
6102 const Layout* layout,
6103 const unsigned char* pshdrs,
6104 typename Sized_relobj<32, big_endian>::Views* pviews)
6106 // Call parent to relocate sections.
6107 Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
6110 // We do not generate stubs if doing a relocatable link.
6111 if (parameters->options().relocatable())
6114 // Relocate stub tables.
6115 unsigned int shnum = this->shnum();
6117 Target_arm<big_endian>* arm_target =
6118 Target_arm<big_endian>::default_target();
6120 Relocate_info<32, big_endian> relinfo;
6121 relinfo.symtab = symtab;
6122 relinfo.layout = layout;
6123 relinfo.object = this;
6125 for (unsigned int i = 1; i < shnum; ++i)
6127 Arm_input_section<big_endian>* arm_input_section =
6128 arm_target->find_arm_input_section(this, i);
6130 if (arm_input_section != NULL
6131 && arm_input_section->is_stub_table_owner()
6132 && !arm_input_section->stub_table()->empty())
6134 // We cannot discard a section if it owns a stub table.
6135 Output_section* os = this->output_section(i);
6136 gold_assert(os != NULL);
6138 relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
6139 relinfo.reloc_shdr = NULL;
6140 relinfo.data_shndx = i;
6141 relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
6143 gold_assert((*pviews)[i].view != NULL);
6145 // We are passed the output section view. Adjust it to cover the
6147 Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
6148 gold_assert((stub_table->address() >= (*pviews)[i].address)
6149 && ((stub_table->address() + stub_table->data_size())
6150 <= (*pviews)[i].address + (*pviews)[i].view_size));
6152 off_t offset = stub_table->address() - (*pviews)[i].address;
6153 unsigned char* view = (*pviews)[i].view + offset;
6154 Arm_address address = stub_table->address();
6155 section_size_type view_size = stub_table->data_size();
6157 stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
6161 // Apply Cortex A8 workaround if applicable.
6162 if (this->section_has_cortex_a8_workaround(i))
6164 unsigned char* view = (*pviews)[i].view;
6165 Arm_address view_address = (*pviews)[i].address;
6166 section_size_type view_size = (*pviews)[i].view_size;
6167 Stub_table<big_endian>* stub_table = this->stub_tables_[i];
6169 // Adjust view to cover section.
6170 Output_section* os = this->output_section(i);
6171 gold_assert(os != NULL);
6172 Arm_address section_address =
6173 this->simple_input_section_output_address(i, os);
6174 uint64_t section_size = this->section_size(i);
6176 gold_assert(section_address >= view_address
6177 && ((section_address + section_size)
6178 <= (view_address + view_size)));
6180 unsigned char* section_view = view + (section_address - view_address);
6182 // Apply the Cortex-A8 workaround to the output address range
6183 // corresponding to this input section.
6184 stub_table->apply_cortex_a8_workaround_to_address_range(
6193 // Find the linked text section of an EXIDX section by looking the the first
6194 // relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
6195 // must be linked to to its associated code section via the sh_link field of
6196 // its section header. However, some tools are broken and the link is not
6197 // always set. LD just drops such an EXIDX section silently, causing the
6198 // associated code not unwindabled. Here we try a little bit harder to
6199 // discover the linked code section.
6201 // PSHDR points to the section header of a relocation section of an EXIDX
6202 // section. If we can find a linked text section, return true and
6203 // store the text section index in the location PSHNDX. Otherwise
6206 template<bool big_endian>
6208 Arm_relobj<big_endian>::find_linked_text_section(
6209 const unsigned char* pshdr,
6210 const unsigned char* psyms,
6211 unsigned int* pshndx)
6213 elfcpp::Shdr<32, big_endian> shdr(pshdr);
6215 // If there is no relocation, we cannot find the linked text section.
6217 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6218 reloc_size = elfcpp::Elf_sizes<32>::rel_size;
6220 reloc_size = elfcpp::Elf_sizes<32>::rela_size;
6221 size_t reloc_count = shdr.get_sh_size() / reloc_size;
6223 // Get the relocations.
6224 const unsigned char* prelocs =
6225 this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
6227 // Find the REL31 relocation for the first word of the first EXIDX entry.
6228 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
6230 Arm_address r_offset;
6231 typename elfcpp::Elf_types<32>::Elf_WXword r_info;
6232 if (shdr.get_sh_type() == elfcpp::SHT_REL)
6234 typename elfcpp::Rel<32, big_endian> reloc(prelocs);
6235 r_info = reloc.get_r_info();
6236 r_offset = reloc.get_r_offset();
6240 typename elfcpp::Rela<32, big_endian> reloc(prelocs);
6241 r_info = reloc.get_r_info();
6242 r_offset = reloc.get_r_offset();
6245 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
6246 if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
6249 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
6251 || r_sym >= this->local_symbol_count()
6255 // This is the relocation for the first word of the first EXIDX entry.
6256 // We expect to see a local section symbol.
6257 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6258 elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
6259 if (sym.get_st_type() == elfcpp::STT_SECTION)
6261 *pshndx = this->adjust_shndx(sym.get_st_shndx());
6271 // Make an EXIDX input section object for an EXIDX section whose index is
6272 // SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
6273 // is the section index of the linked text section.
6275 template<bool big_endian>
6277 Arm_relobj<big_endian>::make_exidx_input_section(
6279 const elfcpp::Shdr<32, big_endian>& shdr,
6280 unsigned int text_shndx)
6282 // Issue an error and ignore this EXIDX section if it points to a text
6283 // section already has an EXIDX section.
6284 if (this->exidx_section_map_[text_shndx] != NULL)
6286 gold_error(_("EXIDX sections %u and %u both link to text section %u "
6288 shndx, this->exidx_section_map_[text_shndx]->shndx(),
6289 text_shndx, this->name().c_str());
6293 // Create an Arm_exidx_input_section object for this EXIDX section.
6294 Arm_exidx_input_section* exidx_input_section =
6295 new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
6296 shdr.get_sh_addralign());
6297 this->exidx_section_map_[text_shndx] = exidx_input_section;
6299 // Also map the EXIDX section index to this.
6300 gold_assert(this->exidx_section_map_[shndx] == NULL);
6301 this->exidx_section_map_[shndx] = exidx_input_section;
6304 // Read the symbol information.
6306 template<bool big_endian>
6308 Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6310 // Call parent class to read symbol information.
6311 Sized_relobj<32, big_endian>::do_read_symbols(sd);
6313 // Read processor-specific flags in ELF file header.
6314 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6315 elfcpp::Elf_sizes<32>::ehdr_size,
6317 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6318 this->processor_specific_flags_ = ehdr.get_e_flags();
6320 // Go over the section headers and look for .ARM.attributes and .ARM.exidx
6322 std::vector<unsigned int> deferred_exidx_sections;
6323 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6324 const unsigned char* pshdrs = sd->section_headers->data();
6325 const unsigned char *ps = pshdrs + shdr_size;
6326 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6328 elfcpp::Shdr<32, big_endian> shdr(ps);
6329 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6331 gold_assert(this->attributes_section_data_ == NULL);
6332 section_offset_type section_offset = shdr.get_sh_offset();
6333 section_size_type section_size =
6334 convert_to_section_size_type(shdr.get_sh_size());
6335 File_view* view = this->get_lasting_view(section_offset,
6336 section_size, true, false);
6337 this->attributes_section_data_ =
6338 new Attributes_section_data(view->data(), section_size);
6340 else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6342 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6343 if (text_shndx >= this->shnum())
6344 gold_error(_("EXIDX section %u linked to invalid section %u"),
6346 else if (text_shndx == elfcpp::SHN_UNDEF)
6347 deferred_exidx_sections.push_back(i);
6349 this->make_exidx_input_section(i, shdr, text_shndx);
6353 // Some tools are broken and they do not set the link of EXIDX sections.
6354 // We look at the first relocation to figure out the linked sections.
6355 if (!deferred_exidx_sections.empty())
6357 // We need to go over the section headers again to find the mapping
6358 // from sections being relocated to their relocation sections. This is
6359 // a bit inefficient as we could do that in the loop above. However,
6360 // we do not expect any deferred EXIDX sections normally. So we do not
6361 // want to slow down the most common path.
6362 typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
6363 Reloc_map reloc_map;
6364 ps = pshdrs + shdr_size;
6365 for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
6367 elfcpp::Shdr<32, big_endian> shdr(ps);
6368 elfcpp::Elf_Word sh_type = shdr.get_sh_type();
6369 if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
6371 unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
6372 if (info_shndx >= this->shnum())
6373 gold_error(_("relocation section %u has invalid info %u"),
6375 Reloc_map::value_type value(info_shndx, i);
6376 std::pair<Reloc_map::iterator, bool> result =
6377 reloc_map.insert(value);
6379 gold_error(_("section %u has multiple relocation sections "
6381 info_shndx, i, reloc_map[info_shndx]);
6385 // Read the symbol table section header.
6386 const unsigned int symtab_shndx = this->symtab_shndx();
6387 elfcpp::Shdr<32, big_endian>
6388 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6389 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6391 // Read the local symbols.
6392 const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
6393 const unsigned int loccount = this->local_symbol_count();
6394 gold_assert(loccount == symtabshdr.get_sh_info());
6395 off_t locsize = loccount * sym_size;
6396 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6397 locsize, true, true);
6399 // Process the deferred EXIDX sections.
6400 for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
6402 unsigned int shndx = deferred_exidx_sections[i];
6403 elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
6404 unsigned int text_shndx;
6405 Reloc_map::const_iterator it = reloc_map.find(shndx);
6406 if (it != reloc_map.end()
6407 && find_linked_text_section(pshdrs + it->second * shdr_size,
6408 psyms, &text_shndx))
6409 this->make_exidx_input_section(shndx, shdr, text_shndx);
6411 gold_error(_("EXIDX section %u has no linked text section."),
6417 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
6418 // sections for unwinding. These sections are referenced implicitly by
6419 // text sections linked in the section headers. If we ignore these implict
6420 // references, the .ARM.exidx sections and any .ARM.extab sections they use
6421 // will be garbage-collected incorrectly. Hence we override the same function
6422 // in the base class to handle these implicit references.
6424 template<bool big_endian>
6426 Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
6428 Read_relocs_data* rd)
6430 // First, call base class method to process relocations in this object.
6431 Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
6433 // If --gc-sections is not specified, there is nothing more to do.
6434 // This happens when --icf is used but --gc-sections is not.
6435 if (!parameters->options().gc_sections())
6438 unsigned int shnum = this->shnum();
6439 const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6440 const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
6444 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
6445 // to these from the linked text sections.
6446 const unsigned char* ps = pshdrs + shdr_size;
6447 for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
6449 elfcpp::Shdr<32, big_endian> shdr(ps);
6450 if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
6452 // Found an .ARM.exidx section, add it to the set of reachable
6453 // sections from its linked text section.
6454 unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
6455 symtab->gc()->add_reference(this, text_shndx, this, i);
6460 // Update output local symbol count. Owing to EXIDX entry merging, some local
6461 // symbols will be removed in output. Adjust output local symbol count
6462 // accordingly. We can only changed the static output local symbol count. It
6463 // is too late to change the dynamic symbols.
6465 template<bool big_endian>
6467 Arm_relobj<big_endian>::update_output_local_symbol_count()
6469 // Caller should check that this needs updating. We want caller checking
6470 // because output_local_symbol_count_needs_update() is most likely inlined.
6471 gold_assert(this->output_local_symbol_count_needs_update_);
6473 gold_assert(this->symtab_shndx() != -1U);
6474 if (this->symtab_shndx() == 0)
6476 // This object has no symbols. Weird but legal.
6480 // Read the symbol table section header.
6481 const unsigned int symtab_shndx = this->symtab_shndx();
6482 elfcpp::Shdr<32, big_endian>
6483 symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
6484 gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
6486 // Read the local symbols.
6487 const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
6488 const unsigned int loccount = this->local_symbol_count();
6489 gold_assert(loccount == symtabshdr.get_sh_info());
6490 off_t locsize = loccount * sym_size;
6491 const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
6492 locsize, true, true);
6494 // Loop over the local symbols.
6496 typedef typename Sized_relobj<32, big_endian>::Output_sections
6498 const Output_sections& out_sections(this->output_sections());
6499 unsigned int shnum = this->shnum();
6500 unsigned int count = 0;
6501 // Skip the first, dummy, symbol.
6503 for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
6505 elfcpp::Sym<32, big_endian> sym(psyms);
6507 Symbol_value<32>& lv((*this->local_values())[i]);
6509 // This local symbol was already discarded by do_count_local_symbols.
6510 if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
6514 unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
6519 Output_section* os = out_sections[shndx];
6521 // This local symbol no longer has an output section. Discard it.
6524 lv.set_no_output_symtab_entry();
6528 // Currently we only discard parts of EXIDX input sections.
6529 // We explicitly check for a merged EXIDX input section to avoid
6530 // calling Output_section_data::output_offset unless necessary.
6531 if ((this->get_output_section_offset(shndx) == invalid_address)
6532 && (this->exidx_input_section_by_shndx(shndx) != NULL))
6534 section_offset_type output_offset =
6535 os->output_offset(this, shndx, lv.input_value());
6536 if (output_offset == -1)
6538 // This symbol is defined in a part of an EXIDX input section
6539 // that is discarded due to entry merging.
6540 lv.set_no_output_symtab_entry();
6549 this->set_output_local_symbol_count(count);
6550 this->output_local_symbol_count_needs_update_ = false;
6553 // Arm_dynobj methods.
6555 // Read the symbol information.
6557 template<bool big_endian>
6559 Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
6561 // Call parent class to read symbol information.
6562 Sized_dynobj<32, big_endian>::do_read_symbols(sd);
6564 // Read processor-specific flags in ELF file header.
6565 const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
6566 elfcpp::Elf_sizes<32>::ehdr_size,
6568 elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
6569 this->processor_specific_flags_ = ehdr.get_e_flags();
6571 // Read the attributes section if there is one.
6572 // We read from the end because gas seems to put it near the end of
6573 // the section headers.
6574 const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
6575 const unsigned char *ps =
6576 sd->section_headers->data() + shdr_size * (this->shnum() - 1);
6577 for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
6579 elfcpp::Shdr<32, big_endian> shdr(ps);
6580 if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
6582 section_offset_type section_offset = shdr.get_sh_offset();
6583 section_size_type section_size =
6584 convert_to_section_size_type(shdr.get_sh_size());
6585 File_view* view = this->get_lasting_view(section_offset,
6586 section_size, true, false);
6587 this->attributes_section_data_ =
6588 new Attributes_section_data(view->data(), section_size);
6594 // Stub_addend_reader methods.
6596 // Read the addend of a REL relocation of type R_TYPE at VIEW.
6598 template<bool big_endian>
6599 elfcpp::Elf_types<32>::Elf_Swxword
6600 Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
6601 unsigned int r_type,
6602 const unsigned char* view,
6603 const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
6605 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
6609 case elfcpp::R_ARM_CALL:
6610 case elfcpp::R_ARM_JUMP24:
6611 case elfcpp::R_ARM_PLT32:
6613 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6614 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6615 Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
6616 return utils::sign_extend<26>(val << 2);
6619 case elfcpp::R_ARM_THM_CALL:
6620 case elfcpp::R_ARM_THM_JUMP24:
6621 case elfcpp::R_ARM_THM_XPC22:
6623 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6624 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6625 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6626 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6627 return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
6630 case elfcpp::R_ARM_THM_JUMP19:
6632 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
6633 const Valtype* wv = reinterpret_cast<const Valtype*>(view);
6634 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
6635 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
6636 return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
6644 // Arm_output_data_got methods.
6646 // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
6647 // The first one is initialized to be 1, which is the module index for
6648 // the main executable and the second one 0. A reloc of the type
6649 // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
6650 // be applied by gold. GSYM is a global symbol.
6652 template<bool big_endian>
6654 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6655 unsigned int got_type,
6658 if (gsym->has_got_offset(got_type))
6661 // We are doing a static link. Just mark it as belong to module 1,
6663 unsigned int got_offset = this->add_constant(1);
6664 gsym->set_got_offset(got_type, got_offset);
6665 got_offset = this->add_constant(0);
6666 this->static_relocs_.push_back(Static_reloc(got_offset,
6667 elfcpp::R_ARM_TLS_DTPOFF32,
6671 // Same as the above but for a local symbol.
6673 template<bool big_endian>
6675 Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
6676 unsigned int got_type,
6677 Sized_relobj<32, big_endian>* object,
6680 if (object->local_has_got_offset(index, got_type))
6683 // We are doing a static link. Just mark it as belong to module 1,
6685 unsigned int got_offset = this->add_constant(1);
6686 object->set_local_got_offset(index, got_type, got_offset);
6687 got_offset = this->add_constant(0);
6688 this->static_relocs_.push_back(Static_reloc(got_offset,
6689 elfcpp::R_ARM_TLS_DTPOFF32,
6693 template<bool big_endian>
6695 Arm_output_data_got<big_endian>::do_write(Output_file* of)
6697 // Call parent to write out GOT.
6698 Output_data_got<32, big_endian>::do_write(of);
6700 // We are done if there is no fix up.
6701 if (this->static_relocs_.empty())
6704 gold_assert(parameters->doing_static_link());
6706 const off_t offset = this->offset();
6707 const section_size_type oview_size =
6708 convert_to_section_size_type(this->data_size());
6709 unsigned char* const oview = of->get_output_view(offset, oview_size);
6711 Output_segment* tls_segment = this->layout_->tls_segment();
6712 gold_assert(tls_segment != NULL);
6714 // The thread pointer $tp points to the TCB, which is followed by the
6715 // TLS. So we need to adjust $tp relative addressing by this amount.
6716 Arm_address aligned_tcb_size =
6717 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
6719 for (size_t i = 0; i < this->static_relocs_.size(); ++i)
6721 Static_reloc& reloc(this->static_relocs_[i]);
6724 if (!reloc.symbol_is_global())
6726 Sized_relobj<32, big_endian>* object = reloc.relobj();
6727 const Symbol_value<32>* psymval =
6728 reloc.relobj()->local_symbol(reloc.index());
6730 // We are doing static linking. Issue an error and skip this
6731 // relocation if the symbol is undefined or in a discarded_section.
6733 unsigned int shndx = psymval->input_shndx(&is_ordinary);
6734 if ((shndx == elfcpp::SHN_UNDEF)
6736 && shndx != elfcpp::SHN_UNDEF
6737 && !object->is_section_included(shndx)
6738 && !this->symbol_table_->is_section_folded(object, shndx)))
6740 gold_error(_("undefined or discarded local symbol %u from "
6741 " object %s in GOT"),
6742 reloc.index(), reloc.relobj()->name().c_str());
6746 value = psymval->value(object, 0);
6750 const Symbol* gsym = reloc.symbol();
6751 gold_assert(gsym != NULL);
6752 if (gsym->is_forwarder())
6753 gsym = this->symbol_table_->resolve_forwards(gsym);
6755 // We are doing static linking. Issue an error and skip this
6756 // relocation if the symbol is undefined or in a discarded_section
6757 // unless it is a weakly_undefined symbol.
6758 if ((gsym->is_defined_in_discarded_section()
6759 || gsym->is_undefined())
6760 && !gsym->is_weak_undefined())
6762 gold_error(_("undefined or discarded symbol %s in GOT"),
6767 if (!gsym->is_weak_undefined())
6769 const Sized_symbol<32>* sym =
6770 static_cast<const Sized_symbol<32>*>(gsym);
6771 value = sym->value();
6777 unsigned got_offset = reloc.got_offset();
6778 gold_assert(got_offset < oview_size);
6780 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
6781 Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
6783 switch (reloc.r_type())
6785 case elfcpp::R_ARM_TLS_DTPOFF32:
6788 case elfcpp::R_ARM_TLS_TPOFF32:
6789 x = value + aligned_tcb_size;
6794 elfcpp::Swap<32, big_endian>::writeval(wv, x);
6797 of->write_output_view(offset, oview_size, oview);
6800 // A class to handle the PLT data.
6802 template<bool big_endian>
6803 class Output_data_plt_arm : public Output_section_data
6806 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
6809 Output_data_plt_arm(Layout*, Output_data_space*);
6811 // Add an entry to the PLT.
6813 add_entry(Symbol* gsym);
6815 // Return the .rel.plt section data.
6816 const Reloc_section*
6818 { return this->rel_; }
6822 do_adjust_output_section(Output_section* os);
6824 // Write to a map file.
6826 do_print_to_mapfile(Mapfile* mapfile) const
6827 { mapfile->print_output_data(this, _("** PLT")); }
6830 // Template for the first PLT entry.
6831 static const uint32_t first_plt_entry[5];
6833 // Template for subsequent PLT entries.
6834 static const uint32_t plt_entry[3];
6836 // Set the final size.
6838 set_final_data_size()
6840 this->set_data_size(sizeof(first_plt_entry)
6841 + this->count_ * sizeof(plt_entry));
6844 // Write out the PLT data.
6846 do_write(Output_file*);
6848 // The reloc section.
6849 Reloc_section* rel_;
6850 // The .got.plt section.
6851 Output_data_space* got_plt_;
6852 // The number of PLT entries.
6853 unsigned int count_;
6856 // Create the PLT section. The ordinary .got section is an argument,
6857 // since we need to refer to the start. We also create our own .got
6858 // section just for PLT entries.
6860 template<bool big_endian>
6861 Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
6862 Output_data_space* got_plt)
6863 : Output_section_data(4), got_plt_(got_plt), count_(0)
6865 this->rel_ = new Reloc_section(false);
6866 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
6867 elfcpp::SHF_ALLOC, this->rel_, true, false,
6871 template<bool big_endian>
6873 Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
6878 // Add an entry to the PLT.
6880 template<bool big_endian>
6882 Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
6884 gold_assert(!gsym->has_plt_offset());
6886 // Note that when setting the PLT offset we skip the initial
6887 // reserved PLT entry.
6888 gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
6889 + sizeof(first_plt_entry));
6893 section_offset_type got_offset = this->got_plt_->current_data_size();
6895 // Every PLT entry needs a GOT entry which points back to the PLT
6896 // entry (this will be changed by the dynamic linker, normally
6897 // lazily when the function is called).
6898 this->got_plt_->set_current_data_size(got_offset + 4);
6900 // Every PLT entry needs a reloc.
6901 gsym->set_needs_dynsym_entry();
6902 this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
6905 // Note that we don't need to save the symbol. The contents of the
6906 // PLT are independent of which symbols are used. The symbols only
6907 // appear in the relocations.
6911 // FIXME: This is not very flexible. Right now this has only been tested
6912 // on armv5te. If we are to support additional architecture features like
6913 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
6915 // The first entry in the PLT.
6916 template<bool big_endian>
6917 const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
6919 0xe52de004, // str lr, [sp, #-4]!
6920 0xe59fe004, // ldr lr, [pc, #4]
6921 0xe08fe00e, // add lr, pc, lr
6922 0xe5bef008, // ldr pc, [lr, #8]!
6923 0x00000000, // &GOT[0] - .
6926 // Subsequent entries in the PLT.
6928 template<bool big_endian>
6929 const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
6931 0xe28fc600, // add ip, pc, #0xNN00000
6932 0xe28cca00, // add ip, ip, #0xNN000
6933 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
6936 // Write out the PLT. This uses the hand-coded instructions above,
6937 // and adjusts them as needed. This is all specified by the arm ELF
6938 // Processor Supplement.
6940 template<bool big_endian>
6942 Output_data_plt_arm<big_endian>::do_write(Output_file* of)
6944 const off_t offset = this->offset();
6945 const section_size_type oview_size =
6946 convert_to_section_size_type(this->data_size());
6947 unsigned char* const oview = of->get_output_view(offset, oview_size);
6949 const off_t got_file_offset = this->got_plt_->offset();
6950 const section_size_type got_size =
6951 convert_to_section_size_type(this->got_plt_->data_size());
6952 unsigned char* const got_view = of->get_output_view(got_file_offset,
6954 unsigned char* pov = oview;
6956 Arm_address plt_address = this->address();
6957 Arm_address got_address = this->got_plt_->address();
6959 // Write first PLT entry. All but the last word are constants.
6960 const size_t num_first_plt_words = (sizeof(first_plt_entry)
6961 / sizeof(plt_entry[0]));
6962 for (size_t i = 0; i < num_first_plt_words - 1; i++)
6963 elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
6964 // Last word in first PLT entry is &GOT[0] - .
6965 elfcpp::Swap<32, big_endian>::writeval(pov + 16,
6966 got_address - (plt_address + 16));
6967 pov += sizeof(first_plt_entry);
6969 unsigned char* got_pov = got_view;
6971 memset(got_pov, 0, 12);
6974 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
6975 unsigned int plt_offset = sizeof(first_plt_entry);
6976 unsigned int plt_rel_offset = 0;
6977 unsigned int got_offset = 12;
6978 const unsigned int count = this->count_;
6979 for (unsigned int i = 0;
6982 pov += sizeof(plt_entry),
6984 plt_offset += sizeof(plt_entry),
6985 plt_rel_offset += rel_size,
6988 // Set and adjust the PLT entry itself.
6989 int32_t offset = ((got_address + got_offset)
6990 - (plt_address + plt_offset + 8));
6992 gold_assert(offset >= 0 && offset < 0x0fffffff);
6993 uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
6994 elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
6995 uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
6996 elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
6997 uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
6998 elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
7000 // Set the entry in the GOT.
7001 elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
7004 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
7005 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
7007 of->write_output_view(offset, oview_size, oview);
7008 of->write_output_view(got_file_offset, got_size, got_view);
7011 // Create a PLT entry for a global symbol.
7013 template<bool big_endian>
7015 Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
7018 if (gsym->has_plt_offset())
7021 if (this->plt_ == NULL)
7023 // Create the GOT sections first.
7024 this->got_section(symtab, layout);
7026 this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
7027 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
7029 | elfcpp::SHF_EXECINSTR),
7030 this->plt_, false, false, false, false);
7032 this->plt_->add_entry(gsym);
7035 // Get the section to use for TLS_DESC relocations.
7037 template<bool big_endian>
7038 typename Target_arm<big_endian>::Reloc_section*
7039 Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
7041 return this->plt_section()->rel_tls_desc(layout);
7044 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
7046 template<bool big_endian>
7048 Target_arm<big_endian>::define_tls_base_symbol(
7049 Symbol_table* symtab,
7052 if (this->tls_base_symbol_defined_)
7055 Output_segment* tls_segment = layout->tls_segment();
7056 if (tls_segment != NULL)
7058 bool is_exec = parameters->options().output_is_executable();
7059 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
7060 Symbol_table::PREDEFINED,
7064 elfcpp::STV_HIDDEN, 0,
7066 ? Symbol::SEGMENT_END
7067 : Symbol::SEGMENT_START),
7070 this->tls_base_symbol_defined_ = true;
7073 // Create a GOT entry for the TLS module index.
7075 template<bool big_endian>
7077 Target_arm<big_endian>::got_mod_index_entry(
7078 Symbol_table* symtab,
7080 Sized_relobj<32, big_endian>* object)
7082 if (this->got_mod_index_offset_ == -1U)
7084 gold_assert(symtab != NULL && layout != NULL && object != NULL);
7085 Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
7086 unsigned int got_offset;
7087 if (!parameters->doing_static_link())
7089 got_offset = got->add_constant(0);
7090 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
7091 rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
7096 // We are doing a static link. Just mark it as belong to module 1,
7098 got_offset = got->add_constant(1);
7101 got->add_constant(0);
7102 this->got_mod_index_offset_ = got_offset;
7104 return this->got_mod_index_offset_;
7107 // Optimize the TLS relocation type based on what we know about the
7108 // symbol. IS_FINAL is true if the final address of this symbol is
7109 // known at link time.
7111 template<bool big_endian>
7112 tls::Tls_optimization
7113 Target_arm<big_endian>::optimize_tls_reloc(bool, int)
7115 // FIXME: Currently we do not do any TLS optimization.
7116 return tls::TLSOPT_NONE;
7119 // Report an unsupported relocation against a local symbol.
7121 template<bool big_endian>
7123 Target_arm<big_endian>::Scan::unsupported_reloc_local(
7124 Sized_relobj<32, big_endian>* object,
7125 unsigned int r_type)
7127 gold_error(_("%s: unsupported reloc %u against local symbol"),
7128 object->name().c_str(), r_type);
7131 // We are about to emit a dynamic relocation of type R_TYPE. If the
7132 // dynamic linker does not support it, issue an error. The GNU linker
7133 // only issues a non-PIC error for an allocated read-only section.
7134 // Here we know the section is allocated, but we don't know that it is
7135 // read-only. But we check for all the relocation types which the
7136 // glibc dynamic linker supports, so it seems appropriate to issue an
7137 // error even if the section is not read-only.
7139 template<bool big_endian>
7141 Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
7142 unsigned int r_type)
7146 // These are the relocation types supported by glibc for ARM.
7147 case elfcpp::R_ARM_RELATIVE:
7148 case elfcpp::R_ARM_COPY:
7149 case elfcpp::R_ARM_GLOB_DAT:
7150 case elfcpp::R_ARM_JUMP_SLOT:
7151 case elfcpp::R_ARM_ABS32:
7152 case elfcpp::R_ARM_ABS32_NOI:
7153 case elfcpp::R_ARM_PC24:
7154 // FIXME: The following 3 types are not supported by Android's dynamic
7156 case elfcpp::R_ARM_TLS_DTPMOD32:
7157 case elfcpp::R_ARM_TLS_DTPOFF32:
7158 case elfcpp::R_ARM_TLS_TPOFF32:
7163 // This prevents us from issuing more than one error per reloc
7164 // section. But we can still wind up issuing more than one
7165 // error per object file.
7166 if (this->issued_non_pic_error_)
7168 const Arm_reloc_property* reloc_property =
7169 arm_reloc_property_table->get_reloc_property(r_type);
7170 gold_assert(reloc_property != NULL);
7171 object->error(_("requires unsupported dynamic reloc %s; "
7172 "recompile with -fPIC"),
7173 reloc_property->name().c_str());
7174 this->issued_non_pic_error_ = true;
7178 case elfcpp::R_ARM_NONE:
7183 // Scan a relocation for a local symbol.
7184 // FIXME: This only handles a subset of relocation types used by Android
7185 // on ARM v5te devices.
7187 template<bool big_endian>
7189 Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
7192 Sized_relobj<32, big_endian>* object,
7193 unsigned int data_shndx,
7194 Output_section* output_section,
7195 const elfcpp::Rel<32, big_endian>& reloc,
7196 unsigned int r_type,
7197 const elfcpp::Sym<32, big_endian>& lsym)
7199 r_type = get_real_reloc_type(r_type);
7202 case elfcpp::R_ARM_NONE:
7203 case elfcpp::R_ARM_V4BX:
7204 case elfcpp::R_ARM_GNU_VTENTRY:
7205 case elfcpp::R_ARM_GNU_VTINHERIT:
7208 case elfcpp::R_ARM_ABS32:
7209 case elfcpp::R_ARM_ABS32_NOI:
7210 // If building a shared library (or a position-independent
7211 // executable), we need to create a dynamic relocation for
7212 // this location. The relocation applied at link time will
7213 // apply the link-time value, so we flag the location with
7214 // an R_ARM_RELATIVE relocation so the dynamic loader can
7215 // relocate it easily.
7216 if (parameters->options().output_is_position_independent())
7218 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7219 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7220 // If we are to add more other reloc types than R_ARM_ABS32,
7221 // we need to add check_non_pic(object, r_type) here.
7222 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
7223 output_section, data_shndx,
7224 reloc.get_r_offset());
7228 case elfcpp::R_ARM_ABS16:
7229 case elfcpp::R_ARM_ABS12:
7230 case elfcpp::R_ARM_THM_ABS5:
7231 case elfcpp::R_ARM_ABS8:
7232 case elfcpp::R_ARM_BASE_ABS:
7233 case elfcpp::R_ARM_MOVW_ABS_NC:
7234 case elfcpp::R_ARM_MOVT_ABS:
7235 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7236 case elfcpp::R_ARM_THM_MOVT_ABS:
7237 // If building a shared library (or a position-independent
7238 // executable), we need to create a dynamic relocation for
7239 // this location. Because the addend needs to remain in the
7240 // data section, we need to be careful not to apply this
7241 // relocation statically.
7242 if (parameters->options().output_is_position_independent())
7244 check_non_pic(object, r_type);
7245 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7246 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7247 if (lsym.get_st_type() != elfcpp::STT_SECTION)
7248 rel_dyn->add_local(object, r_sym, r_type, output_section,
7249 data_shndx, reloc.get_r_offset());
7252 gold_assert(lsym.get_st_value() == 0);
7253 unsigned int shndx = lsym.get_st_shndx();
7255 shndx = object->adjust_sym_shndx(r_sym, shndx,
7258 object->error(_("section symbol %u has bad shndx %u"),
7261 rel_dyn->add_local_section(object, shndx,
7262 r_type, output_section,
7263 data_shndx, reloc.get_r_offset());
7268 case elfcpp::R_ARM_PC24:
7269 case elfcpp::R_ARM_REL32:
7270 case elfcpp::R_ARM_LDR_PC_G0:
7271 case elfcpp::R_ARM_SBREL32:
7272 case elfcpp::R_ARM_THM_CALL:
7273 case elfcpp::R_ARM_THM_PC8:
7274 case elfcpp::R_ARM_BASE_PREL:
7275 case elfcpp::R_ARM_PLT32:
7276 case elfcpp::R_ARM_CALL:
7277 case elfcpp::R_ARM_JUMP24:
7278 case elfcpp::R_ARM_THM_JUMP24:
7279 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7280 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7281 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7282 case elfcpp::R_ARM_SBREL31:
7283 case elfcpp::R_ARM_PREL31:
7284 case elfcpp::R_ARM_MOVW_PREL_NC:
7285 case elfcpp::R_ARM_MOVT_PREL:
7286 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7287 case elfcpp::R_ARM_THM_MOVT_PREL:
7288 case elfcpp::R_ARM_THM_JUMP19:
7289 case elfcpp::R_ARM_THM_JUMP6:
7290 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7291 case elfcpp::R_ARM_THM_PC12:
7292 case elfcpp::R_ARM_REL32_NOI:
7293 case elfcpp::R_ARM_ALU_PC_G0_NC:
7294 case elfcpp::R_ARM_ALU_PC_G0:
7295 case elfcpp::R_ARM_ALU_PC_G1_NC:
7296 case elfcpp::R_ARM_ALU_PC_G1:
7297 case elfcpp::R_ARM_ALU_PC_G2:
7298 case elfcpp::R_ARM_LDR_PC_G1:
7299 case elfcpp::R_ARM_LDR_PC_G2:
7300 case elfcpp::R_ARM_LDRS_PC_G0:
7301 case elfcpp::R_ARM_LDRS_PC_G1:
7302 case elfcpp::R_ARM_LDRS_PC_G2:
7303 case elfcpp::R_ARM_LDC_PC_G0:
7304 case elfcpp::R_ARM_LDC_PC_G1:
7305 case elfcpp::R_ARM_LDC_PC_G2:
7306 case elfcpp::R_ARM_ALU_SB_G0_NC:
7307 case elfcpp::R_ARM_ALU_SB_G0:
7308 case elfcpp::R_ARM_ALU_SB_G1_NC:
7309 case elfcpp::R_ARM_ALU_SB_G1:
7310 case elfcpp::R_ARM_ALU_SB_G2:
7311 case elfcpp::R_ARM_LDR_SB_G0:
7312 case elfcpp::R_ARM_LDR_SB_G1:
7313 case elfcpp::R_ARM_LDR_SB_G2:
7314 case elfcpp::R_ARM_LDRS_SB_G0:
7315 case elfcpp::R_ARM_LDRS_SB_G1:
7316 case elfcpp::R_ARM_LDRS_SB_G2:
7317 case elfcpp::R_ARM_LDC_SB_G0:
7318 case elfcpp::R_ARM_LDC_SB_G1:
7319 case elfcpp::R_ARM_LDC_SB_G2:
7320 case elfcpp::R_ARM_MOVW_BREL_NC:
7321 case elfcpp::R_ARM_MOVT_BREL:
7322 case elfcpp::R_ARM_MOVW_BREL:
7323 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7324 case elfcpp::R_ARM_THM_MOVT_BREL:
7325 case elfcpp::R_ARM_THM_MOVW_BREL:
7326 case elfcpp::R_ARM_THM_JUMP11:
7327 case elfcpp::R_ARM_THM_JUMP8:
7328 // We don't need to do anything for a relative addressing relocation
7329 // against a local symbol if it does not reference the GOT.
7332 case elfcpp::R_ARM_GOTOFF32:
7333 case elfcpp::R_ARM_GOTOFF12:
7334 // We need a GOT section:
7335 target->got_section(symtab, layout);
7338 case elfcpp::R_ARM_GOT_BREL:
7339 case elfcpp::R_ARM_GOT_PREL:
7341 // The symbol requires a GOT entry.
7342 Arm_output_data_got<big_endian>* got =
7343 target->got_section(symtab, layout);
7344 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7345 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
7347 // If we are generating a shared object, we need to add a
7348 // dynamic RELATIVE relocation for this symbol's GOT entry.
7349 if (parameters->options().output_is_position_independent())
7351 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7352 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7353 rel_dyn->add_local_relative(
7354 object, r_sym, elfcpp::R_ARM_RELATIVE, got,
7355 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
7361 case elfcpp::R_ARM_TARGET1:
7362 case elfcpp::R_ARM_TARGET2:
7363 // This should have been mapped to another type already.
7365 case elfcpp::R_ARM_COPY:
7366 case elfcpp::R_ARM_GLOB_DAT:
7367 case elfcpp::R_ARM_JUMP_SLOT:
7368 case elfcpp::R_ARM_RELATIVE:
7369 // These are relocations which should only be seen by the
7370 // dynamic linker, and should never be seen here.
7371 gold_error(_("%s: unexpected reloc %u in object file"),
7372 object->name().c_str(), r_type);
7376 // These are initial TLS relocs, which are expected when
7378 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7379 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7380 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7381 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7382 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7384 bool output_is_shared = parameters->options().shared();
7385 const tls::Tls_optimization optimized_type
7386 = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
7390 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7391 if (optimized_type == tls::TLSOPT_NONE)
7393 // Create a pair of GOT entries for the module index and
7394 // dtv-relative offset.
7395 Arm_output_data_got<big_endian>* got
7396 = target->got_section(symtab, layout);
7397 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7398 unsigned int shndx = lsym.get_st_shndx();
7400 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
7403 object->error(_("local symbol %u has bad shndx %u"),
7408 if (!parameters->doing_static_link())
7409 got->add_local_pair_with_rel(object, r_sym, shndx,
7411 target->rel_dyn_section(layout),
7412 elfcpp::R_ARM_TLS_DTPMOD32, 0);
7414 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
7418 // FIXME: TLS optimization not supported yet.
7422 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7423 if (optimized_type == tls::TLSOPT_NONE)
7425 // Create a GOT entry for the module index.
7426 target->got_mod_index_entry(symtab, layout, object);
7429 // FIXME: TLS optimization not supported yet.
7433 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7436 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7437 layout->set_has_static_tls();
7438 if (optimized_type == tls::TLSOPT_NONE)
7440 // Create a GOT entry for the tp-relative offset.
7441 Arm_output_data_got<big_endian>* got
7442 = target->got_section(symtab, layout);
7443 unsigned int r_sym =
7444 elfcpp::elf_r_sym<32>(reloc.get_r_info());
7445 if (!parameters->doing_static_link())
7446 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
7447 target->rel_dyn_section(layout),
7448 elfcpp::R_ARM_TLS_TPOFF32);
7449 else if (!object->local_has_got_offset(r_sym,
7450 GOT_TYPE_TLS_OFFSET))
7452 got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
7453 unsigned int got_offset =
7454 object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
7455 got->add_static_reloc(got_offset,
7456 elfcpp::R_ARM_TLS_TPOFF32, object,
7461 // FIXME: TLS optimization not supported yet.
7465 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7466 layout->set_has_static_tls();
7467 if (output_is_shared)
7469 // We need to create a dynamic relocation.
7470 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7471 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7472 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7473 rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
7474 output_section, data_shndx,
7475 reloc.get_r_offset());
7486 unsupported_reloc_local(object, r_type);
7491 // Report an unsupported relocation against a global symbol.
7493 template<bool big_endian>
7495 Target_arm<big_endian>::Scan::unsupported_reloc_global(
7496 Sized_relobj<32, big_endian>* object,
7497 unsigned int r_type,
7500 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
7501 object->name().c_str(), r_type, gsym->demangled_name().c_str());
7504 // Scan a relocation for a global symbol.
7506 template<bool big_endian>
7508 Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
7511 Sized_relobj<32, big_endian>* object,
7512 unsigned int data_shndx,
7513 Output_section* output_section,
7514 const elfcpp::Rel<32, big_endian>& reloc,
7515 unsigned int r_type,
7518 // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
7519 // section. We check here to avoid creating a dynamic reloc against
7520 // _GLOBAL_OFFSET_TABLE_.
7521 if (!target->has_got_section()
7522 && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
7523 target->got_section(symtab, layout);
7525 r_type = get_real_reloc_type(r_type);
7528 case elfcpp::R_ARM_NONE:
7529 case elfcpp::R_ARM_V4BX:
7530 case elfcpp::R_ARM_GNU_VTENTRY:
7531 case elfcpp::R_ARM_GNU_VTINHERIT:
7534 case elfcpp::R_ARM_ABS32:
7535 case elfcpp::R_ARM_ABS16:
7536 case elfcpp::R_ARM_ABS12:
7537 case elfcpp::R_ARM_THM_ABS5:
7538 case elfcpp::R_ARM_ABS8:
7539 case elfcpp::R_ARM_BASE_ABS:
7540 case elfcpp::R_ARM_MOVW_ABS_NC:
7541 case elfcpp::R_ARM_MOVT_ABS:
7542 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
7543 case elfcpp::R_ARM_THM_MOVT_ABS:
7544 case elfcpp::R_ARM_ABS32_NOI:
7545 // Absolute addressing relocations.
7547 // Make a PLT entry if necessary.
7548 if (this->symbol_needs_plt_entry(gsym))
7550 target->make_plt_entry(symtab, layout, gsym);
7551 // Since this is not a PC-relative relocation, we may be
7552 // taking the address of a function. In that case we need to
7553 // set the entry in the dynamic symbol table to the address of
7555 if (gsym->is_from_dynobj() && !parameters->options().shared())
7556 gsym->set_needs_dynsym_value();
7558 // Make a dynamic relocation if necessary.
7559 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
7561 if (gsym->may_need_copy_reloc())
7563 target->copy_reloc(symtab, layout, object,
7564 data_shndx, output_section, gsym, reloc);
7566 else if ((r_type == elfcpp::R_ARM_ABS32
7567 || r_type == elfcpp::R_ARM_ABS32_NOI)
7568 && gsym->can_use_relative_reloc(false))
7570 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7571 rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
7572 output_section, object,
7573 data_shndx, reloc.get_r_offset());
7577 check_non_pic(object, r_type);
7578 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7579 rel_dyn->add_global(gsym, r_type, output_section, object,
7580 data_shndx, reloc.get_r_offset());
7586 case elfcpp::R_ARM_GOTOFF32:
7587 case elfcpp::R_ARM_GOTOFF12:
7588 // We need a GOT section.
7589 target->got_section(symtab, layout);
7592 case elfcpp::R_ARM_REL32:
7593 case elfcpp::R_ARM_LDR_PC_G0:
7594 case elfcpp::R_ARM_SBREL32:
7595 case elfcpp::R_ARM_THM_PC8:
7596 case elfcpp::R_ARM_BASE_PREL:
7597 case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
7598 case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
7599 case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
7600 case elfcpp::R_ARM_MOVW_PREL_NC:
7601 case elfcpp::R_ARM_MOVT_PREL:
7602 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
7603 case elfcpp::R_ARM_THM_MOVT_PREL:
7604 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
7605 case elfcpp::R_ARM_THM_PC12:
7606 case elfcpp::R_ARM_REL32_NOI:
7607 case elfcpp::R_ARM_ALU_PC_G0_NC:
7608 case elfcpp::R_ARM_ALU_PC_G0:
7609 case elfcpp::R_ARM_ALU_PC_G1_NC:
7610 case elfcpp::R_ARM_ALU_PC_G1:
7611 case elfcpp::R_ARM_ALU_PC_G2:
7612 case elfcpp::R_ARM_LDR_PC_G1:
7613 case elfcpp::R_ARM_LDR_PC_G2:
7614 case elfcpp::R_ARM_LDRS_PC_G0:
7615 case elfcpp::R_ARM_LDRS_PC_G1:
7616 case elfcpp::R_ARM_LDRS_PC_G2:
7617 case elfcpp::R_ARM_LDC_PC_G0:
7618 case elfcpp::R_ARM_LDC_PC_G1:
7619 case elfcpp::R_ARM_LDC_PC_G2:
7620 case elfcpp::R_ARM_ALU_SB_G0_NC:
7621 case elfcpp::R_ARM_ALU_SB_G0:
7622 case elfcpp::R_ARM_ALU_SB_G1_NC:
7623 case elfcpp::R_ARM_ALU_SB_G1:
7624 case elfcpp::R_ARM_ALU_SB_G2:
7625 case elfcpp::R_ARM_LDR_SB_G0:
7626 case elfcpp::R_ARM_LDR_SB_G1:
7627 case elfcpp::R_ARM_LDR_SB_G2:
7628 case elfcpp::R_ARM_LDRS_SB_G0:
7629 case elfcpp::R_ARM_LDRS_SB_G1:
7630 case elfcpp::R_ARM_LDRS_SB_G2:
7631 case elfcpp::R_ARM_LDC_SB_G0:
7632 case elfcpp::R_ARM_LDC_SB_G1:
7633 case elfcpp::R_ARM_LDC_SB_G2:
7634 case elfcpp::R_ARM_MOVW_BREL_NC:
7635 case elfcpp::R_ARM_MOVT_BREL:
7636 case elfcpp::R_ARM_MOVW_BREL:
7637 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
7638 case elfcpp::R_ARM_THM_MOVT_BREL:
7639 case elfcpp::R_ARM_THM_MOVW_BREL:
7640 // Relative addressing relocations.
7642 // Make a dynamic relocation if necessary.
7643 int flags = Symbol::NON_PIC_REF;
7644 if (gsym->needs_dynamic_reloc(flags))
7646 if (target->may_need_copy_reloc(gsym))
7648 target->copy_reloc(symtab, layout, object,
7649 data_shndx, output_section, gsym, reloc);
7653 check_non_pic(object, r_type);
7654 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7655 rel_dyn->add_global(gsym, r_type, output_section, object,
7656 data_shndx, reloc.get_r_offset());
7662 case elfcpp::R_ARM_PC24:
7663 case elfcpp::R_ARM_THM_CALL:
7664 case elfcpp::R_ARM_PLT32:
7665 case elfcpp::R_ARM_CALL:
7666 case elfcpp::R_ARM_JUMP24:
7667 case elfcpp::R_ARM_THM_JUMP24:
7668 case elfcpp::R_ARM_SBREL31:
7669 case elfcpp::R_ARM_PREL31:
7670 case elfcpp::R_ARM_THM_JUMP19:
7671 case elfcpp::R_ARM_THM_JUMP6:
7672 case elfcpp::R_ARM_THM_JUMP11:
7673 case elfcpp::R_ARM_THM_JUMP8:
7674 // All the relocation above are branches except for the PREL31 ones.
7675 // A PREL31 relocation can point to a personality function in a shared
7676 // library. In that case we want to use a PLT because we want to
7677 // call the personality routine and the dyanmic linkers we care about
7678 // do not support dynamic PREL31 relocations. An REL31 relocation may
7679 // point to a function whose unwinding behaviour is being described but
7680 // we will not mistakenly generate a PLT for that because we should use
7681 // a local section symbol.
7683 // If the symbol is fully resolved, this is just a relative
7684 // local reloc. Otherwise we need a PLT entry.
7685 if (gsym->final_value_is_known())
7687 // If building a shared library, we can also skip the PLT entry
7688 // if the symbol is defined in the output file and is protected
7690 if (gsym->is_defined()
7691 && !gsym->is_from_dynobj()
7692 && !gsym->is_preemptible())
7694 target->make_plt_entry(symtab, layout, gsym);
7697 case elfcpp::R_ARM_GOT_BREL:
7698 case elfcpp::R_ARM_GOT_ABS:
7699 case elfcpp::R_ARM_GOT_PREL:
7701 // The symbol requires a GOT entry.
7702 Arm_output_data_got<big_endian>* got =
7703 target->got_section(symtab, layout);
7704 if (gsym->final_value_is_known())
7705 got->add_global(gsym, GOT_TYPE_STANDARD);
7708 // If this symbol is not fully resolved, we need to add a
7709 // GOT entry with a dynamic relocation.
7710 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7711 if (gsym->is_from_dynobj()
7712 || gsym->is_undefined()
7713 || gsym->is_preemptible())
7714 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
7715 rel_dyn, elfcpp::R_ARM_GLOB_DAT);
7718 if (got->add_global(gsym, GOT_TYPE_STANDARD))
7719 rel_dyn->add_global_relative(
7720 gsym, elfcpp::R_ARM_RELATIVE, got,
7721 gsym->got_offset(GOT_TYPE_STANDARD));
7727 case elfcpp::R_ARM_TARGET1:
7728 case elfcpp::R_ARM_TARGET2:
7729 // These should have been mapped to other types already.
7731 case elfcpp::R_ARM_COPY:
7732 case elfcpp::R_ARM_GLOB_DAT:
7733 case elfcpp::R_ARM_JUMP_SLOT:
7734 case elfcpp::R_ARM_RELATIVE:
7735 // These are relocations which should only be seen by the
7736 // dynamic linker, and should never be seen here.
7737 gold_error(_("%s: unexpected reloc %u in object file"),
7738 object->name().c_str(), r_type);
7741 // These are initial tls relocs, which are expected when
7743 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
7744 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7745 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7746 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7747 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7749 const bool is_final = gsym->final_value_is_known();
7750 const tls::Tls_optimization optimized_type
7751 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
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 if (!parameters->doing_static_link())
7762 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
7763 target->rel_dyn_section(layout),
7764 elfcpp::R_ARM_TLS_DTPMOD32,
7765 elfcpp::R_ARM_TLS_DTPOFF32);
7767 got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
7770 // FIXME: TLS optimization not supported yet.
7774 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
7775 if (optimized_type == tls::TLSOPT_NONE)
7777 // Create a GOT entry for the module index.
7778 target->got_mod_index_entry(symtab, layout, object);
7781 // FIXME: TLS optimization not supported yet.
7785 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
7788 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
7789 layout->set_has_static_tls();
7790 if (optimized_type == tls::TLSOPT_NONE)
7792 // Create a GOT entry for the tp-relative offset.
7793 Arm_output_data_got<big_endian>* got
7794 = target->got_section(symtab, layout);
7795 if (!parameters->doing_static_link())
7796 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
7797 target->rel_dyn_section(layout),
7798 elfcpp::R_ARM_TLS_TPOFF32);
7799 else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
7801 got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
7802 unsigned int got_offset =
7803 gsym->got_offset(GOT_TYPE_TLS_OFFSET);
7804 got->add_static_reloc(got_offset,
7805 elfcpp::R_ARM_TLS_TPOFF32, gsym);
7809 // FIXME: TLS optimization not supported yet.
7813 case elfcpp::R_ARM_TLS_LE32: // Local-exec
7814 layout->set_has_static_tls();
7815 if (parameters->options().shared())
7817 // We need to create a dynamic relocation.
7818 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
7819 rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
7820 output_section, object,
7821 data_shndx, reloc.get_r_offset());
7832 unsupported_reloc_global(object, r_type, gsym);
7837 // Process relocations for gc.
7839 template<bool big_endian>
7841 Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
7843 Sized_relobj<32, big_endian>* object,
7844 unsigned int data_shndx,
7846 const unsigned char* prelocs,
7848 Output_section* output_section,
7849 bool needs_special_offset_handling,
7850 size_t local_symbol_count,
7851 const unsigned char* plocal_symbols)
7853 typedef Target_arm<big_endian> Arm;
7854 typedef typename Target_arm<big_endian>::Scan Scan;
7856 gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
7865 needs_special_offset_handling,
7870 // Scan relocations for a section.
7872 template<bool big_endian>
7874 Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
7876 Sized_relobj<32, big_endian>* object,
7877 unsigned int data_shndx,
7878 unsigned int sh_type,
7879 const unsigned char* prelocs,
7881 Output_section* output_section,
7882 bool needs_special_offset_handling,
7883 size_t local_symbol_count,
7884 const unsigned char* plocal_symbols)
7886 typedef typename Target_arm<big_endian>::Scan Scan;
7887 if (sh_type == elfcpp::SHT_RELA)
7889 gold_error(_("%s: unsupported RELA reloc section"),
7890 object->name().c_str());
7894 gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
7903 needs_special_offset_handling,
7908 // Finalize the sections.
7910 template<bool big_endian>
7912 Target_arm<big_endian>::do_finalize_sections(
7914 const Input_objects* input_objects,
7915 Symbol_table* symtab)
7917 // Create an empty uninitialized attribute section if we still don't have it
7919 if (this->attributes_section_data_ == NULL)
7920 this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
7922 // Merge processor-specific flags.
7923 for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
7924 p != input_objects->relobj_end();
7927 // If this input file is a binary file, it has no processor
7928 // specific flags and attributes section.
7929 Input_file::Format format = (*p)->input_file()->format();
7930 if (format != Input_file::FORMAT_ELF)
7932 gold_assert(format == Input_file::FORMAT_BINARY);
7936 Arm_relobj<big_endian>* arm_relobj =
7937 Arm_relobj<big_endian>::as_arm_relobj(*p);
7938 this->merge_processor_specific_flags(
7940 arm_relobj->processor_specific_flags());
7941 this->merge_object_attributes(arm_relobj->name().c_str(),
7942 arm_relobj->attributes_section_data());
7946 for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
7947 p != input_objects->dynobj_end();
7950 Arm_dynobj<big_endian>* arm_dynobj =
7951 Arm_dynobj<big_endian>::as_arm_dynobj(*p);
7952 this->merge_processor_specific_flags(
7954 arm_dynobj->processor_specific_flags());
7955 this->merge_object_attributes(arm_dynobj->name().c_str(),
7956 arm_dynobj->attributes_section_data());
7960 const Object_attribute* cpu_arch_attr =
7961 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
7962 if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
7963 this->set_may_use_blx(true);
7965 // Check if we need to use Cortex-A8 workaround.
7966 if (parameters->options().user_set_fix_cortex_a8())
7967 this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
7970 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
7971 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
7973 const Object_attribute* cpu_arch_profile_attr =
7974 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
7975 this->fix_cortex_a8_ =
7976 (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
7977 && (cpu_arch_profile_attr->int_value() == 'A'
7978 || cpu_arch_profile_attr->int_value() == 0));
7981 // Check if we can use V4BX interworking.
7982 // The V4BX interworking stub contains BX instruction,
7983 // which is not specified for some profiles.
7984 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
7985 && !this->may_use_blx())
7986 gold_error(_("unable to provide V4BX reloc interworking fix up; "
7987 "the target profile does not support BX instruction"));
7989 // Fill in some more dynamic tags.
7990 const Reloc_section* rel_plt = (this->plt_ == NULL
7992 : this->plt_->rel_plt());
7993 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
7994 this->rel_dyn_, true, false);
7996 // Emit any relocs we saved in an attempt to avoid generating COPY
7998 if (this->copy_relocs_.any_saved_relocs())
7999 this->copy_relocs_.emit(this->rel_dyn_section(layout));
8001 // Handle the .ARM.exidx section.
8002 Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
8003 if (exidx_section != NULL
8004 && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
8005 && !parameters->options().relocatable())
8007 // Create __exidx_start and __exdix_end symbols.
8008 symtab->define_in_output_data("__exidx_start", NULL,
8009 Symbol_table::PREDEFINED,
8010 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8011 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8013 symtab->define_in_output_data("__exidx_end", NULL,
8014 Symbol_table::PREDEFINED,
8015 exidx_section, 0, 0, elfcpp::STT_OBJECT,
8016 elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
8019 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
8020 // the .ARM.exidx section.
8021 if (!layout->script_options()->saw_phdrs_clause())
8023 gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
8025 Output_segment* exidx_segment =
8026 layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
8027 exidx_segment->add_output_section(exidx_section, elfcpp::PF_R,
8032 // Create an .ARM.attributes section if there is not one already.
8033 Output_attributes_section_data* attributes_section =
8034 new Output_attributes_section_data(*this->attributes_section_data_);
8035 layout->add_output_section_data(".ARM.attributes",
8036 elfcpp::SHT_ARM_ATTRIBUTES, 0,
8037 attributes_section, false, false, false,
8041 // Return whether a direct absolute static relocation needs to be applied.
8042 // In cases where Scan::local() or Scan::global() has created
8043 // a dynamic relocation other than R_ARM_RELATIVE, the addend
8044 // of the relocation is carried in the data, and we must not
8045 // apply the static relocation.
8047 template<bool big_endian>
8049 Target_arm<big_endian>::Relocate::should_apply_static_reloc(
8050 const Sized_symbol<32>* gsym,
8053 Output_section* output_section)
8055 // If the output section is not allocated, then we didn't call
8056 // scan_relocs, we didn't create a dynamic reloc, and we must apply
8058 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
8061 // For local symbols, we will have created a non-RELATIVE dynamic
8062 // relocation only if (a) the output is position independent,
8063 // (b) the relocation is absolute (not pc- or segment-relative), and
8064 // (c) the relocation is not 32 bits wide.
8066 return !(parameters->options().output_is_position_independent()
8067 && (ref_flags & Symbol::ABSOLUTE_REF)
8070 // For global symbols, we use the same helper routines used in the
8071 // scan pass. If we did not create a dynamic relocation, or if we
8072 // created a RELATIVE dynamic relocation, we should apply the static
8074 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
8075 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
8076 && gsym->can_use_relative_reloc(ref_flags
8077 & Symbol::FUNCTION_CALL);
8078 return !has_dyn || is_rel;
8081 // Perform a relocation.
8083 template<bool big_endian>
8085 Target_arm<big_endian>::Relocate::relocate(
8086 const Relocate_info<32, big_endian>* relinfo,
8088 Output_section *output_section,
8090 const elfcpp::Rel<32, big_endian>& rel,
8091 unsigned int r_type,
8092 const Sized_symbol<32>* gsym,
8093 const Symbol_value<32>* psymval,
8094 unsigned char* view,
8095 Arm_address address,
8096 section_size_type view_size)
8098 typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
8100 r_type = get_real_reloc_type(r_type);
8101 const Arm_reloc_property* reloc_property =
8102 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8103 if (reloc_property == NULL)
8105 std::string reloc_name =
8106 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8107 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8108 _("cannot relocate %s in object file"),
8109 reloc_name.c_str());
8113 const Arm_relobj<big_endian>* object =
8114 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
8116 // If the final branch target of a relocation is THUMB instruction, this
8117 // is 1. Otherwise it is 0.
8118 Arm_address thumb_bit = 0;
8119 Symbol_value<32> symval;
8120 bool is_weakly_undefined_without_plt = false;
8121 if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
8125 // This is a global symbol. Determine if we use PLT and if the
8126 // final target is THUMB.
8127 if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
8129 // This uses a PLT, change the symbol value.
8130 symval.set_output_value(target->plt_section()->address()
8131 + gsym->plt_offset());
8134 else if (gsym->is_weak_undefined())
8136 // This is a weakly undefined symbol and we do not use PLT
8137 // for this relocation. A branch targeting this symbol will
8138 // be converted into an NOP.
8139 is_weakly_undefined_without_plt = true;
8143 // Set thumb bit if symbol:
8144 // -Has type STT_ARM_TFUNC or
8145 // -Has type STT_FUNC, is defined and with LSB in value set.
8147 (((gsym->type() == elfcpp::STT_ARM_TFUNC)
8148 || (gsym->type() == elfcpp::STT_FUNC
8149 && !gsym->is_undefined()
8150 && ((psymval->value(object, 0) & 1) != 0)))
8157 // This is a local symbol. Determine if the final target is THUMB.
8158 // We saved this information when all the local symbols were read.
8159 elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
8160 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
8161 thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
8166 // This is a fake relocation synthesized for a stub. It does not have
8167 // a real symbol. We just look at the LSB of the symbol value to
8168 // determine if the target is THUMB or not.
8169 thumb_bit = ((psymval->value(object, 0) & 1) != 0);
8172 // Strip LSB if this points to a THUMB target.
8174 && reloc_property->uses_thumb_bit()
8175 && ((psymval->value(object, 0) & 1) != 0))
8177 Arm_address stripped_value =
8178 psymval->value(object, 0) & ~static_cast<Arm_address>(1);
8179 symval.set_output_value(stripped_value);
8183 // Get the GOT offset if needed.
8184 // The GOT pointer points to the end of the GOT section.
8185 // We need to subtract the size of the GOT section to get
8186 // the actual offset to use in the relocation.
8187 bool have_got_offset = false;
8188 unsigned int got_offset = 0;
8191 case elfcpp::R_ARM_GOT_BREL:
8192 case elfcpp::R_ARM_GOT_PREL:
8195 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
8196 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
8197 - target->got_size());
8201 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8202 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
8203 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
8204 - target->got_size());
8206 have_got_offset = true;
8213 // To look up relocation stubs, we need to pass the symbol table index of
8215 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8217 // Get the addressing origin of the output segment defining the
8218 // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
8219 Arm_address sym_origin = 0;
8220 if (reloc_property->uses_symbol_base())
8222 if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
8223 // R_ARM_BASE_ABS with the NULL symbol will give the
8224 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
8225 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
8226 sym_origin = target->got_plt_section()->address();
8227 else if (gsym == NULL)
8229 else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
8230 sym_origin = gsym->output_segment()->vaddr();
8231 else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
8232 sym_origin = gsym->output_data()->address();
8234 // TODO: Assumes the segment base to be zero for the global symbols
8235 // till the proper support for the segment-base-relative addressing
8236 // will be implemented. This is consistent with GNU ld.
8239 // For relative addressing relocation, find out the relative address base.
8240 Arm_address relative_address_base = 0;
8241 switch(reloc_property->relative_address_base())
8243 case Arm_reloc_property::RAB_NONE:
8244 // Relocations with relative address bases RAB_TLS and RAB_tp are
8245 // handled by relocate_tls. So we do not need to do anything here.
8246 case Arm_reloc_property::RAB_TLS:
8247 case Arm_reloc_property::RAB_tp:
8249 case Arm_reloc_property::RAB_B_S:
8250 relative_address_base = sym_origin;
8252 case Arm_reloc_property::RAB_GOT_ORG:
8253 relative_address_base = target->got_plt_section()->address();
8255 case Arm_reloc_property::RAB_P:
8256 relative_address_base = address;
8258 case Arm_reloc_property::RAB_Pa:
8259 relative_address_base = address & 0xfffffffcU;
8265 typename Arm_relocate_functions::Status reloc_status =
8266 Arm_relocate_functions::STATUS_OKAY;
8267 bool check_overflow = reloc_property->checks_overflow();
8270 case elfcpp::R_ARM_NONE:
8273 case elfcpp::R_ARM_ABS8:
8274 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8276 reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
8279 case elfcpp::R_ARM_ABS12:
8280 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8282 reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
8285 case elfcpp::R_ARM_ABS16:
8286 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8288 reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
8291 case elfcpp::R_ARM_ABS32:
8292 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8294 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8298 case elfcpp::R_ARM_ABS32_NOI:
8299 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
8301 // No thumb bit for this relocation: (S + A)
8302 reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
8306 case elfcpp::R_ARM_MOVW_ABS_NC:
8307 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8309 reloc_status = Arm_relocate_functions::movw(view, object, psymval,
8314 case elfcpp::R_ARM_MOVT_ABS:
8315 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8317 reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
8320 case elfcpp::R_ARM_THM_MOVW_ABS_NC:
8321 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8323 reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
8324 0, thumb_bit, false);
8327 case elfcpp::R_ARM_THM_MOVT_ABS:
8328 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8330 reloc_status = Arm_relocate_functions::thm_movt(view, object,
8334 case elfcpp::R_ARM_MOVW_PREL_NC:
8335 case elfcpp::R_ARM_MOVW_BREL_NC:
8336 case elfcpp::R_ARM_MOVW_BREL:
8338 Arm_relocate_functions::movw(view, object, psymval,
8339 relative_address_base, thumb_bit,
8343 case elfcpp::R_ARM_MOVT_PREL:
8344 case elfcpp::R_ARM_MOVT_BREL:
8346 Arm_relocate_functions::movt(view, object, psymval,
8347 relative_address_base);
8350 case elfcpp::R_ARM_THM_MOVW_PREL_NC:
8351 case elfcpp::R_ARM_THM_MOVW_BREL_NC:
8352 case elfcpp::R_ARM_THM_MOVW_BREL:
8354 Arm_relocate_functions::thm_movw(view, object, psymval,
8355 relative_address_base,
8356 thumb_bit, check_overflow);
8359 case elfcpp::R_ARM_THM_MOVT_PREL:
8360 case elfcpp::R_ARM_THM_MOVT_BREL:
8362 Arm_relocate_functions::thm_movt(view, object, psymval,
8363 relative_address_base);
8366 case elfcpp::R_ARM_REL32:
8367 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8368 address, thumb_bit);
8371 case elfcpp::R_ARM_THM_ABS5:
8372 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8374 reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
8377 // Thumb long branches.
8378 case elfcpp::R_ARM_THM_CALL:
8379 case elfcpp::R_ARM_THM_XPC22:
8380 case elfcpp::R_ARM_THM_JUMP24:
8382 Arm_relocate_functions::thumb_branch_common(
8383 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8384 thumb_bit, is_weakly_undefined_without_plt);
8387 case elfcpp::R_ARM_GOTOFF32:
8389 Arm_address got_origin;
8390 got_origin = target->got_plt_section()->address();
8391 reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
8392 got_origin, thumb_bit);
8396 case elfcpp::R_ARM_BASE_PREL:
8397 gold_assert(gsym != NULL);
8399 Arm_relocate_functions::base_prel(view, sym_origin, address);
8402 case elfcpp::R_ARM_BASE_ABS:
8404 if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
8408 reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
8412 case elfcpp::R_ARM_GOT_BREL:
8413 gold_assert(have_got_offset);
8414 reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
8417 case elfcpp::R_ARM_GOT_PREL:
8418 gold_assert(have_got_offset);
8419 // Get the address origin for GOT PLT, which is allocated right
8420 // after the GOT section, to calculate an absolute address of
8421 // the symbol GOT entry (got_origin + got_offset).
8422 Arm_address got_origin;
8423 got_origin = target->got_plt_section()->address();
8424 reloc_status = Arm_relocate_functions::got_prel(view,
8425 got_origin + got_offset,
8429 case elfcpp::R_ARM_PLT32:
8430 case elfcpp::R_ARM_CALL:
8431 case elfcpp::R_ARM_JUMP24:
8432 case elfcpp::R_ARM_XPC25:
8433 gold_assert(gsym == NULL
8434 || gsym->has_plt_offset()
8435 || gsym->final_value_is_known()
8436 || (gsym->is_defined()
8437 && !gsym->is_from_dynobj()
8438 && !gsym->is_preemptible()));
8440 Arm_relocate_functions::arm_branch_common(
8441 r_type, relinfo, view, gsym, object, r_sym, psymval, address,
8442 thumb_bit, is_weakly_undefined_without_plt);
8445 case elfcpp::R_ARM_THM_JUMP19:
8447 Arm_relocate_functions::thm_jump19(view, object, psymval, address,
8451 case elfcpp::R_ARM_THM_JUMP6:
8453 Arm_relocate_functions::thm_jump6(view, object, psymval, address);
8456 case elfcpp::R_ARM_THM_JUMP8:
8458 Arm_relocate_functions::thm_jump8(view, object, psymval, address);
8461 case elfcpp::R_ARM_THM_JUMP11:
8463 Arm_relocate_functions::thm_jump11(view, object, psymval, address);
8466 case elfcpp::R_ARM_PREL31:
8467 reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
8468 address, thumb_bit);
8471 case elfcpp::R_ARM_V4BX:
8472 if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
8474 const bool is_v4bx_interworking =
8475 (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
8477 Arm_relocate_functions::v4bx(relinfo, view, object, address,
8478 is_v4bx_interworking);
8482 case elfcpp::R_ARM_THM_PC8:
8484 Arm_relocate_functions::thm_pc8(view, object, psymval, address);
8487 case elfcpp::R_ARM_THM_PC12:
8489 Arm_relocate_functions::thm_pc12(view, object, psymval, address);
8492 case elfcpp::R_ARM_THM_ALU_PREL_11_0:
8494 Arm_relocate_functions::thm_alu11(view, object, psymval, address,
8498 case elfcpp::R_ARM_ALU_PC_G0_NC:
8499 case elfcpp::R_ARM_ALU_PC_G0:
8500 case elfcpp::R_ARM_ALU_PC_G1_NC:
8501 case elfcpp::R_ARM_ALU_PC_G1:
8502 case elfcpp::R_ARM_ALU_PC_G2:
8503 case elfcpp::R_ARM_ALU_SB_G0_NC:
8504 case elfcpp::R_ARM_ALU_SB_G0:
8505 case elfcpp::R_ARM_ALU_SB_G1_NC:
8506 case elfcpp::R_ARM_ALU_SB_G1:
8507 case elfcpp::R_ARM_ALU_SB_G2:
8509 Arm_relocate_functions::arm_grp_alu(view, object, psymval,
8510 reloc_property->group_index(),
8511 relative_address_base,
8512 thumb_bit, check_overflow);
8515 case elfcpp::R_ARM_LDR_PC_G0:
8516 case elfcpp::R_ARM_LDR_PC_G1:
8517 case elfcpp::R_ARM_LDR_PC_G2:
8518 case elfcpp::R_ARM_LDR_SB_G0:
8519 case elfcpp::R_ARM_LDR_SB_G1:
8520 case elfcpp::R_ARM_LDR_SB_G2:
8522 Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
8523 reloc_property->group_index(),
8524 relative_address_base);
8527 case elfcpp::R_ARM_LDRS_PC_G0:
8528 case elfcpp::R_ARM_LDRS_PC_G1:
8529 case elfcpp::R_ARM_LDRS_PC_G2:
8530 case elfcpp::R_ARM_LDRS_SB_G0:
8531 case elfcpp::R_ARM_LDRS_SB_G1:
8532 case elfcpp::R_ARM_LDRS_SB_G2:
8534 Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
8535 reloc_property->group_index(),
8536 relative_address_base);
8539 case elfcpp::R_ARM_LDC_PC_G0:
8540 case elfcpp::R_ARM_LDC_PC_G1:
8541 case elfcpp::R_ARM_LDC_PC_G2:
8542 case elfcpp::R_ARM_LDC_SB_G0:
8543 case elfcpp::R_ARM_LDC_SB_G1:
8544 case elfcpp::R_ARM_LDC_SB_G2:
8546 Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
8547 reloc_property->group_index(),
8548 relative_address_base);
8551 // These are initial tls relocs, which are expected when
8553 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8554 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8555 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8556 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8557 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8559 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
8560 view, address, view_size);
8567 // Report any errors.
8568 switch (reloc_status)
8570 case Arm_relocate_functions::STATUS_OKAY:
8572 case Arm_relocate_functions::STATUS_OVERFLOW:
8573 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8574 _("relocation overflow in relocation %u"),
8577 case Arm_relocate_functions::STATUS_BAD_RELOC:
8578 gold_error_at_location(
8582 _("unexpected opcode while processing relocation %u"),
8592 // Perform a TLS relocation.
8594 template<bool big_endian>
8595 inline typename Arm_relocate_functions<big_endian>::Status
8596 Target_arm<big_endian>::Relocate::relocate_tls(
8597 const Relocate_info<32, big_endian>* relinfo,
8598 Target_arm<big_endian>* target,
8600 const elfcpp::Rel<32, big_endian>& rel,
8601 unsigned int r_type,
8602 const Sized_symbol<32>* gsym,
8603 const Symbol_value<32>* psymval,
8604 unsigned char* view,
8605 elfcpp::Elf_types<32>::Elf_Addr address,
8606 section_size_type /*view_size*/ )
8608 typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
8609 typedef Relocate_functions<32, big_endian> RelocFuncs;
8610 Output_segment* tls_segment = relinfo->layout->tls_segment();
8612 const Sized_relobj<32, big_endian>* object = relinfo->object;
8614 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
8616 const bool is_final = (gsym == NULL
8617 ? !parameters->options().shared()
8618 : gsym->final_value_is_known());
8619 const tls::Tls_optimization optimized_type
8620 = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
8623 case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
8625 unsigned int got_type = GOT_TYPE_TLS_PAIR;
8626 unsigned int got_offset;
8629 gold_assert(gsym->has_got_offset(got_type));
8630 got_offset = gsym->got_offset(got_type) - target->got_size();
8634 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8635 gold_assert(object->local_has_got_offset(r_sym, got_type));
8636 got_offset = (object->local_got_offset(r_sym, got_type)
8637 - target->got_size());
8639 if (optimized_type == tls::TLSOPT_NONE)
8641 Arm_address got_entry =
8642 target->got_plt_section()->address() + got_offset;
8644 // Relocate the field with the PC relative offset of the pair of
8646 RelocFuncs::pcrel32(view, got_entry, address);
8647 return ArmRelocFuncs::STATUS_OKAY;
8652 case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
8653 if (optimized_type == tls::TLSOPT_NONE)
8655 // Relocate the field with the offset of the GOT entry for
8656 // the module index.
8657 unsigned int got_offset;
8658 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
8659 - target->got_size());
8660 Arm_address got_entry =
8661 target->got_plt_section()->address() + got_offset;
8663 // Relocate the field with the PC relative offset of the pair of
8665 RelocFuncs::pcrel32(view, got_entry, address);
8666 return ArmRelocFuncs::STATUS_OKAY;
8670 case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
8671 RelocFuncs::rel32(view, value);
8672 return ArmRelocFuncs::STATUS_OKAY;
8674 case elfcpp::R_ARM_TLS_IE32: // Initial-exec
8675 if (optimized_type == tls::TLSOPT_NONE)
8677 // Relocate the field with the offset of the GOT entry for
8678 // the tp-relative offset of the symbol.
8679 unsigned int got_type = GOT_TYPE_TLS_OFFSET;
8680 unsigned int got_offset;
8683 gold_assert(gsym->has_got_offset(got_type));
8684 got_offset = gsym->got_offset(got_type);
8688 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
8689 gold_assert(object->local_has_got_offset(r_sym, got_type));
8690 got_offset = object->local_got_offset(r_sym, got_type);
8693 // All GOT offsets are relative to the end of the GOT.
8694 got_offset -= target->got_size();
8696 Arm_address got_entry =
8697 target->got_plt_section()->address() + got_offset;
8699 // Relocate the field with the PC relative offset of the GOT entry.
8700 RelocFuncs::pcrel32(view, got_entry, address);
8701 return ArmRelocFuncs::STATUS_OKAY;
8705 case elfcpp::R_ARM_TLS_LE32: // Local-exec
8706 // If we're creating a shared library, a dynamic relocation will
8707 // have been created for this location, so do not apply it now.
8708 if (!parameters->options().shared())
8710 gold_assert(tls_segment != NULL);
8712 // $tp points to the TCB, which is followed by the TLS, so we
8713 // need to add TCB size to the offset.
8714 Arm_address aligned_tcb_size =
8715 align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
8716 RelocFuncs::rel32(view, value + aligned_tcb_size);
8719 return ArmRelocFuncs::STATUS_OKAY;
8725 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
8726 _("unsupported reloc %u"),
8728 return ArmRelocFuncs::STATUS_BAD_RELOC;
8731 // Relocate section data.
8733 template<bool big_endian>
8735 Target_arm<big_endian>::relocate_section(
8736 const Relocate_info<32, big_endian>* relinfo,
8737 unsigned int sh_type,
8738 const unsigned char* prelocs,
8740 Output_section* output_section,
8741 bool needs_special_offset_handling,
8742 unsigned char* view,
8743 Arm_address address,
8744 section_size_type view_size,
8745 const Reloc_symbol_changes* reloc_symbol_changes)
8747 typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
8748 gold_assert(sh_type == elfcpp::SHT_REL);
8750 // See if we are relocating a relaxed input section. If so, the view
8751 // covers the whole output section and we need to adjust accordingly.
8752 if (needs_special_offset_handling)
8754 const Output_relaxed_input_section* poris =
8755 output_section->find_relaxed_input_section(relinfo->object,
8756 relinfo->data_shndx);
8759 Arm_address section_address = poris->address();
8760 section_size_type section_size = poris->data_size();
8762 gold_assert((section_address >= address)
8763 && ((section_address + section_size)
8764 <= (address + view_size)));
8766 off_t offset = section_address - address;
8769 view_size = section_size;
8773 gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
8780 needs_special_offset_handling,
8784 reloc_symbol_changes);
8787 // Return the size of a relocation while scanning during a relocatable
8790 template<bool big_endian>
8792 Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
8793 unsigned int r_type,
8796 r_type = get_real_reloc_type(r_type);
8797 const Arm_reloc_property* arp =
8798 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
8803 std::string reloc_name =
8804 arm_reloc_property_table->reloc_name_in_error_message(r_type);
8805 gold_error(_("%s: unexpected %s in object file"),
8806 object->name().c_str(), reloc_name.c_str());
8811 // Scan the relocs during a relocatable link.
8813 template<bool big_endian>
8815 Target_arm<big_endian>::scan_relocatable_relocs(
8816 Symbol_table* symtab,
8818 Sized_relobj<32, big_endian>* object,
8819 unsigned int data_shndx,
8820 unsigned int sh_type,
8821 const unsigned char* prelocs,
8823 Output_section* output_section,
8824 bool needs_special_offset_handling,
8825 size_t local_symbol_count,
8826 const unsigned char* plocal_symbols,
8827 Relocatable_relocs* rr)
8829 gold_assert(sh_type == elfcpp::SHT_REL);
8831 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
8832 Relocatable_size_for_reloc> Scan_relocatable_relocs;
8834 gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
8835 Scan_relocatable_relocs>(
8843 needs_special_offset_handling,
8849 // Relocate a section during a relocatable link.
8851 template<bool big_endian>
8853 Target_arm<big_endian>::relocate_for_relocatable(
8854 const Relocate_info<32, big_endian>* relinfo,
8855 unsigned int sh_type,
8856 const unsigned char* prelocs,
8858 Output_section* output_section,
8859 off_t offset_in_output_section,
8860 const Relocatable_relocs* rr,
8861 unsigned char* view,
8862 Arm_address view_address,
8863 section_size_type view_size,
8864 unsigned char* reloc_view,
8865 section_size_type reloc_view_size)
8867 gold_assert(sh_type == elfcpp::SHT_REL);
8869 gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
8874 offset_in_output_section,
8883 // Return the value to use for a dynamic symbol which requires special
8884 // treatment. This is how we support equality comparisons of function
8885 // pointers across shared library boundaries, as described in the
8886 // processor specific ABI supplement.
8888 template<bool big_endian>
8890 Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
8892 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
8893 return this->plt_section()->address() + gsym->plt_offset();
8896 // Map platform-specific relocs to real relocs
8898 template<bool big_endian>
8900 Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
8904 case elfcpp::R_ARM_TARGET1:
8905 // This is either R_ARM_ABS32 or R_ARM_REL32;
8906 return elfcpp::R_ARM_ABS32;
8908 case elfcpp::R_ARM_TARGET2:
8909 // This can be any reloc type but ususally is R_ARM_GOT_PREL
8910 return elfcpp::R_ARM_GOT_PREL;
8917 // Whether if two EABI versions V1 and V2 are compatible.
8919 template<bool big_endian>
8921 Target_arm<big_endian>::are_eabi_versions_compatible(
8922 elfcpp::Elf_Word v1,
8923 elfcpp::Elf_Word v2)
8925 // v4 and v5 are the same spec before and after it was released,
8926 // so allow mixing them.
8927 if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
8928 || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
8934 // Combine FLAGS from an input object called NAME and the processor-specific
8935 // flags in the ELF header of the output. Much of this is adapted from the
8936 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
8937 // in bfd/elf32-arm.c.
8939 template<bool big_endian>
8941 Target_arm<big_endian>::merge_processor_specific_flags(
8942 const std::string& name,
8943 elfcpp::Elf_Word flags)
8945 if (this->are_processor_specific_flags_set())
8947 elfcpp::Elf_Word out_flags = this->processor_specific_flags();
8949 // Nothing to merge if flags equal to those in output.
8950 if (flags == out_flags)
8953 // Complain about various flag mismatches.
8954 elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
8955 elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
8956 if (!this->are_eabi_versions_compatible(version1, version2))
8957 gold_error(_("Source object %s has EABI version %d but output has "
8958 "EABI version %d."),
8960 (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
8961 (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
8965 // If the input is the default architecture and had the default
8966 // flags then do not bother setting the flags for the output
8967 // architecture, instead allow future merges to do this. If no
8968 // future merges ever set these flags then they will retain their
8969 // uninitialised values, which surprise surprise, correspond
8970 // to the default values.
8974 // This is the first time, just copy the flags.
8975 // We only copy the EABI version for now.
8976 this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
8980 // Adjust ELF file header.
8981 template<bool big_endian>
8983 Target_arm<big_endian>::do_adjust_elf_header(
8984 unsigned char* view,
8987 gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
8989 elfcpp::Ehdr<32, big_endian> ehdr(view);
8990 unsigned char e_ident[elfcpp::EI_NIDENT];
8991 memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
8993 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
8994 == elfcpp::EF_ARM_EABI_UNKNOWN)
8995 e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
8997 e_ident[elfcpp::EI_OSABI] = 0;
8998 e_ident[elfcpp::EI_ABIVERSION] = 0;
9000 // FIXME: Do EF_ARM_BE8 adjustment.
9002 elfcpp::Ehdr_write<32, big_endian> oehdr(view);
9003 oehdr.put_e_ident(e_ident);
9006 // do_make_elf_object to override the same function in the base class.
9007 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
9008 // to store ARM specific information. Hence we need to have our own
9009 // ELF object creation.
9011 template<bool big_endian>
9013 Target_arm<big_endian>::do_make_elf_object(
9014 const std::string& name,
9015 Input_file* input_file,
9016 off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
9018 int et = ehdr.get_e_type();
9019 if (et == elfcpp::ET_REL)
9021 Arm_relobj<big_endian>* obj =
9022 new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
9026 else if (et == elfcpp::ET_DYN)
9028 Sized_dynobj<32, big_endian>* obj =
9029 new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
9035 gold_error(_("%s: unsupported ELF file type %d"),
9041 // Read the architecture from the Tag_also_compatible_with attribute, if any.
9042 // Returns -1 if no architecture could be read.
9043 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
9045 template<bool big_endian>
9047 Target_arm<big_endian>::get_secondary_compatible_arch(
9048 const Attributes_section_data* pasd)
9050 const Object_attribute *known_attributes =
9051 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9053 // Note: the tag and its argument below are uleb128 values, though
9054 // currently-defined values fit in one byte for each.
9055 const std::string& sv =
9056 known_attributes[elfcpp::Tag_also_compatible_with].string_value();
9058 && sv.data()[0] == elfcpp::Tag_CPU_arch
9059 && (sv.data()[1] & 128) != 128)
9060 return sv.data()[1];
9062 // This tag is "safely ignorable", so don't complain if it looks funny.
9066 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
9067 // The tag is removed if ARCH is -1.
9068 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
9070 template<bool big_endian>
9072 Target_arm<big_endian>::set_secondary_compatible_arch(
9073 Attributes_section_data* pasd,
9076 Object_attribute *known_attributes =
9077 pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
9081 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
9085 // Note: the tag and its argument below are uleb128 values, though
9086 // currently-defined values fit in one byte for each.
9088 sv[0] = elfcpp::Tag_CPU_arch;
9089 gold_assert(arch != 0);
9093 known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
9096 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
9098 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
9100 template<bool big_endian>
9102 Target_arm<big_endian>::tag_cpu_arch_combine(
9105 int* secondary_compat_out,
9107 int secondary_compat)
9109 #define T(X) elfcpp::TAG_CPU_ARCH_##X
9110 static const int v6t2[] =
9122 static const int v6k[] =
9135 static const int v7[] =
9149 static const int v6_m[] =
9164 static const int v6s_m[] =
9180 static const int v7e_m[] =
9197 static const int v4t_plus_v6_m[] =
9213 T(V4T_PLUS_V6_M) // V4T plus V6_M.
9215 static const int *comb[] =
9223 // Pseudo-architecture.
9227 // Check we've not got a higher architecture than we know about.
9229 if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
9231 gold_error(_("%s: unknown CPU architecture"), name);
9235 // Override old tag if we have a Tag_also_compatible_with on the output.
9237 if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
9238 || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
9239 oldtag = T(V4T_PLUS_V6_M);
9241 // And override the new tag if we have a Tag_also_compatible_with on the
9244 if ((newtag == T(V6_M) && secondary_compat == T(V4T))
9245 || (newtag == T(V4T) && secondary_compat == T(V6_M)))
9246 newtag = T(V4T_PLUS_V6_M);
9248 // Architectures before V6KZ add features monotonically.
9249 int tagh = std::max(oldtag, newtag);
9250 if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
9253 int tagl = std::min(oldtag, newtag);
9254 int result = comb[tagh - T(V6T2)][tagl];
9256 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
9257 // as the canonical version.
9258 if (result == T(V4T_PLUS_V6_M))
9261 *secondary_compat_out = T(V6_M);
9264 *secondary_compat_out = -1;
9268 gold_error(_("%s: conflicting CPU architectures %d/%d"),
9269 name, oldtag, newtag);
9277 // Helper to print AEABI enum tag value.
9279 template<bool big_endian>
9281 Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
9283 static const char *aeabi_enum_names[] =
9284 { "", "variable-size", "32-bit", "" };
9285 const size_t aeabi_enum_names_size =
9286 sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
9288 if (value < aeabi_enum_names_size)
9289 return std::string(aeabi_enum_names[value]);
9293 sprintf(buffer, "<unknown value %u>", value);
9294 return std::string(buffer);
9298 // Return the string value to store in TAG_CPU_name.
9300 template<bool big_endian>
9302 Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
9304 static const char *name_table[] = {
9305 // These aren't real CPU names, but we can't guess
9306 // that from the architecture version alone.
9322 const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
9324 if (value < name_table_size)
9325 return std::string(name_table[value]);
9329 sprintf(buffer, "<unknown CPU value %u>", value);
9330 return std::string(buffer);
9334 // Merge object attributes from input file called NAME with those of the
9335 // output. The input object attributes are in the object pointed by PASD.
9337 template<bool big_endian>
9339 Target_arm<big_endian>::merge_object_attributes(
9341 const Attributes_section_data* pasd)
9343 // Return if there is no attributes section data.
9347 // If output has no object attributes, just copy.
9348 if (this->attributes_section_data_ == NULL)
9350 this->attributes_section_data_ = new Attributes_section_data(*pasd);
9354 const int vendor = Object_attribute::OBJ_ATTR_PROC;
9355 const Object_attribute* in_attr = pasd->known_attributes(vendor);
9356 Object_attribute* out_attr =
9357 this->attributes_section_data_->known_attributes(vendor);
9359 // This needs to happen before Tag_ABI_FP_number_model is merged. */
9360 if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
9361 != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
9363 // Ignore mismatches if the object doesn't use floating point. */
9364 if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
9365 out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
9366 in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
9367 else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0)
9368 gold_error(_("%s uses VFP register arguments, output does not"),
9372 for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
9374 // Merge this attribute with existing attributes.
9377 case elfcpp::Tag_CPU_raw_name:
9378 case elfcpp::Tag_CPU_name:
9379 // These are merged after Tag_CPU_arch.
9382 case elfcpp::Tag_ABI_optimization_goals:
9383 case elfcpp::Tag_ABI_FP_optimization_goals:
9384 // Use the first value seen.
9387 case elfcpp::Tag_CPU_arch:
9389 unsigned int saved_out_attr = out_attr->int_value();
9390 // Merge Tag_CPU_arch and Tag_also_compatible_with.
9391 int secondary_compat =
9392 this->get_secondary_compatible_arch(pasd);
9393 int secondary_compat_out =
9394 this->get_secondary_compatible_arch(
9395 this->attributes_section_data_);
9396 out_attr[i].set_int_value(
9397 tag_cpu_arch_combine(name, out_attr[i].int_value(),
9398 &secondary_compat_out,
9399 in_attr[i].int_value(),
9401 this->set_secondary_compatible_arch(this->attributes_section_data_,
9402 secondary_compat_out);
9404 // Merge Tag_CPU_name and Tag_CPU_raw_name.
9405 if (out_attr[i].int_value() == saved_out_attr)
9406 ; // Leave the names alone.
9407 else if (out_attr[i].int_value() == in_attr[i].int_value())
9409 // The output architecture has been changed to match the
9410 // input architecture. Use the input names.
9411 out_attr[elfcpp::Tag_CPU_name].set_string_value(
9412 in_attr[elfcpp::Tag_CPU_name].string_value());
9413 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
9414 in_attr[elfcpp::Tag_CPU_raw_name].string_value());
9418 out_attr[elfcpp::Tag_CPU_name].set_string_value("");
9419 out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
9422 // If we still don't have a value for Tag_CPU_name,
9423 // make one up now. Tag_CPU_raw_name remains blank.
9424 if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
9426 const std::string cpu_name =
9427 this->tag_cpu_name_value(out_attr[i].int_value());
9428 // FIXME: If we see an unknown CPU, this will be set
9429 // to "<unknown CPU n>", where n is the attribute value.
9430 // This is different from BFD, which leaves the name alone.
9431 out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
9436 case elfcpp::Tag_ARM_ISA_use:
9437 case elfcpp::Tag_THUMB_ISA_use:
9438 case elfcpp::Tag_WMMX_arch:
9439 case elfcpp::Tag_Advanced_SIMD_arch:
9440 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
9441 case elfcpp::Tag_ABI_FP_rounding:
9442 case elfcpp::Tag_ABI_FP_exceptions:
9443 case elfcpp::Tag_ABI_FP_user_exceptions:
9444 case elfcpp::Tag_ABI_FP_number_model:
9445 case elfcpp::Tag_VFP_HP_extension:
9446 case elfcpp::Tag_CPU_unaligned_access:
9447 case elfcpp::Tag_T2EE_use:
9448 case elfcpp::Tag_Virtualization_use:
9449 case elfcpp::Tag_MPextension_use:
9450 // Use the largest value specified.
9451 if (in_attr[i].int_value() > out_attr[i].int_value())
9452 out_attr[i].set_int_value(in_attr[i].int_value());
9455 case elfcpp::Tag_ABI_align8_preserved:
9456 case elfcpp::Tag_ABI_PCS_RO_data:
9457 // Use the smallest value specified.
9458 if (in_attr[i].int_value() < out_attr[i].int_value())
9459 out_attr[i].set_int_value(in_attr[i].int_value());
9462 case elfcpp::Tag_ABI_align8_needed:
9463 if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
9464 && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
9465 || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
9468 // This error message should be enabled once all non-conformant
9469 // binaries in the toolchain have had the attributes set
9471 // gold_error(_("output 8-byte data alignment conflicts with %s"),
9475 case elfcpp::Tag_ABI_FP_denormal:
9476 case elfcpp::Tag_ABI_PCS_GOT_use:
9478 // These tags have 0 = don't care, 1 = strong requirement,
9479 // 2 = weak requirement.
9480 static const int order_021[3] = {0, 2, 1};
9482 // Use the "greatest" from the sequence 0, 2, 1, or the largest
9483 // value if greater than 2 (for future-proofing).
9484 if ((in_attr[i].int_value() > 2
9485 && in_attr[i].int_value() > out_attr[i].int_value())
9486 || (in_attr[i].int_value() <= 2
9487 && out_attr[i].int_value() <= 2
9488 && (order_021[in_attr[i].int_value()]
9489 > order_021[out_attr[i].int_value()])))
9490 out_attr[i].set_int_value(in_attr[i].int_value());
9494 case elfcpp::Tag_CPU_arch_profile:
9495 if (out_attr[i].int_value() != in_attr[i].int_value())
9497 // 0 will merge with anything.
9498 // 'A' and 'S' merge to 'A'.
9499 // 'R' and 'S' merge to 'R'.
9500 // 'M' and 'A|R|S' is an error.
9501 if (out_attr[i].int_value() == 0
9502 || (out_attr[i].int_value() == 'S'
9503 && (in_attr[i].int_value() == 'A'
9504 || in_attr[i].int_value() == 'R')))
9505 out_attr[i].set_int_value(in_attr[i].int_value());
9506 else if (in_attr[i].int_value() == 0
9507 || (in_attr[i].int_value() == 'S'
9508 && (out_attr[i].int_value() == 'A'
9509 || out_attr[i].int_value() == 'R')))
9514 (_("conflicting architecture profiles %c/%c"),
9515 in_attr[i].int_value() ? in_attr[i].int_value() : '0',
9516 out_attr[i].int_value() ? out_attr[i].int_value() : '0');
9520 case elfcpp::Tag_VFP_arch:
9537 // Values greater than 6 aren't defined, so just pick the
9539 if (in_attr[i].int_value() > 6
9540 && in_attr[i].int_value() > out_attr[i].int_value())
9542 *out_attr = *in_attr;
9545 // The output uses the superset of input features
9546 // (ISA version) and registers.
9547 int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
9548 vfp_versions[out_attr[i].int_value()].ver);
9549 int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
9550 vfp_versions[out_attr[i].int_value()].regs);
9551 // This assumes all possible supersets are also a valid
9554 for (newval = 6; newval > 0; newval--)
9556 if (regs == vfp_versions[newval].regs
9557 && ver == vfp_versions[newval].ver)
9560 out_attr[i].set_int_value(newval);
9563 case elfcpp::Tag_PCS_config:
9564 if (out_attr[i].int_value() == 0)
9565 out_attr[i].set_int_value(in_attr[i].int_value());
9566 else if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9568 // It's sometimes ok to mix different configs, so this is only
9570 gold_warning(_("%s: conflicting platform configuration"), name);
9573 case elfcpp::Tag_ABI_PCS_R9_use:
9574 if (in_attr[i].int_value() != out_attr[i].int_value()
9575 && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
9576 && in_attr[i].int_value() != elfcpp::AEABI_R9_unused)
9578 gold_error(_("%s: conflicting use of R9"), name);
9580 if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
9581 out_attr[i].set_int_value(in_attr[i].int_value());
9583 case elfcpp::Tag_ABI_PCS_RW_data:
9584 if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
9585 && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9586 != elfcpp::AEABI_R9_SB)
9587 && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
9588 != elfcpp::AEABI_R9_unused))
9590 gold_error(_("%s: SB relative addressing conflicts with use "
9594 // Use the smallest value specified.
9595 if (in_attr[i].int_value() < out_attr[i].int_value())
9596 out_attr[i].set_int_value(in_attr[i].int_value());
9598 case elfcpp::Tag_ABI_PCS_wchar_t:
9599 // FIXME: Make it possible to turn off this warning.
9600 if (out_attr[i].int_value()
9601 && in_attr[i].int_value()
9602 && out_attr[i].int_value() != in_attr[i].int_value())
9604 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
9605 "use %u-byte wchar_t; use of wchar_t values "
9606 "across objects may fail"),
9607 name, in_attr[i].int_value(),
9608 out_attr[i].int_value());
9610 else if (in_attr[i].int_value() && !out_attr[i].int_value())
9611 out_attr[i].set_int_value(in_attr[i].int_value());
9613 case elfcpp::Tag_ABI_enum_size:
9614 if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
9616 if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
9617 || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
9619 // The existing object is compatible with anything.
9620 // Use whatever requirements the new object has.
9621 out_attr[i].set_int_value(in_attr[i].int_value());
9623 // FIXME: Make it possible to turn off this warning.
9624 else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
9625 && out_attr[i].int_value() != in_attr[i].int_value())
9627 unsigned int in_value = in_attr[i].int_value();
9628 unsigned int out_value = out_attr[i].int_value();
9629 gold_warning(_("%s uses %s enums yet the output is to use "
9630 "%s enums; use of enum values across objects "
9633 this->aeabi_enum_name(in_value).c_str(),
9634 this->aeabi_enum_name(out_value).c_str());
9638 case elfcpp::Tag_ABI_VFP_args:
9641 case elfcpp::Tag_ABI_WMMX_args:
9642 if (in_attr[i].int_value() != out_attr[i].int_value())
9644 gold_error(_("%s uses iWMMXt register arguments, output does "
9649 case Object_attribute::Tag_compatibility:
9650 // Merged in target-independent code.
9652 case elfcpp::Tag_ABI_HardFP_use:
9653 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
9654 if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
9655 || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
9656 out_attr[i].set_int_value(3);
9657 else if (in_attr[i].int_value() > out_attr[i].int_value())
9658 out_attr[i].set_int_value(in_attr[i].int_value());
9660 case elfcpp::Tag_ABI_FP_16bit_format:
9661 if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
9663 if (in_attr[i].int_value() != out_attr[i].int_value())
9664 gold_error(_("fp16 format mismatch between %s and output"),
9667 if (in_attr[i].int_value() != 0)
9668 out_attr[i].set_int_value(in_attr[i].int_value());
9671 case elfcpp::Tag_nodefaults:
9672 // This tag is set if it exists, but the value is unused (and is
9673 // typically zero). We don't actually need to do anything here -
9674 // the merge happens automatically when the type flags are merged
9677 case elfcpp::Tag_also_compatible_with:
9678 // Already done in Tag_CPU_arch.
9680 case elfcpp::Tag_conformance:
9681 // Keep the attribute if it matches. Throw it away otherwise.
9682 // No attribute means no claim to conform.
9683 if (in_attr[i].string_value() != out_attr[i].string_value())
9684 out_attr[i].set_string_value("");
9689 const char* err_object = NULL;
9691 // The "known_obj_attributes" table does contain some undefined
9692 // attributes. Ensure that there are unused.
9693 if (out_attr[i].int_value() != 0
9694 || out_attr[i].string_value() != "")
9695 err_object = "output";
9696 else if (in_attr[i].int_value() != 0
9697 || in_attr[i].string_value() != "")
9700 if (err_object != NULL)
9702 // Attribute numbers >=64 (mod 128) can be safely ignored.
9704 gold_error(_("%s: unknown mandatory EABI object attribute "
9708 gold_warning(_("%s: unknown EABI object attribute %d"),
9712 // Only pass on attributes that match in both inputs.
9713 if (!in_attr[i].matches(out_attr[i]))
9715 out_attr[i].set_int_value(0);
9716 out_attr[i].set_string_value("");
9721 // If out_attr was copied from in_attr then it won't have a type yet.
9722 if (in_attr[i].type() && !out_attr[i].type())
9723 out_attr[i].set_type(in_attr[i].type());
9726 // Merge Tag_compatibility attributes and any common GNU ones.
9727 this->attributes_section_data_->merge(name, pasd);
9729 // Check for any attributes not known on ARM.
9730 typedef Vendor_object_attributes::Other_attributes Other_attributes;
9731 const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
9732 Other_attributes::const_iterator in_iter = in_other_attributes->begin();
9733 Other_attributes* out_other_attributes =
9734 this->attributes_section_data_->other_attributes(vendor);
9735 Other_attributes::iterator out_iter = out_other_attributes->begin();
9737 while (in_iter != in_other_attributes->end()
9738 || out_iter != out_other_attributes->end())
9740 const char* err_object = NULL;
9743 // The tags for each list are in numerical order.
9744 // If the tags are equal, then merge.
9745 if (out_iter != out_other_attributes->end()
9746 && (in_iter == in_other_attributes->end()
9747 || in_iter->first > out_iter->first))
9749 // This attribute only exists in output. We can't merge, and we
9750 // don't know what the tag means, so delete it.
9751 err_object = "output";
9752 err_tag = out_iter->first;
9753 int saved_tag = out_iter->first;
9754 delete out_iter->second;
9755 out_other_attributes->erase(out_iter);
9756 out_iter = out_other_attributes->upper_bound(saved_tag);
9758 else if (in_iter != in_other_attributes->end()
9759 && (out_iter != out_other_attributes->end()
9760 || in_iter->first < out_iter->first))
9762 // This attribute only exists in input. We can't merge, and we
9763 // don't know what the tag means, so ignore it.
9765 err_tag = in_iter->first;
9768 else // The tags are equal.
9770 // As present, all attributes in the list are unknown, and
9771 // therefore can't be merged meaningfully.
9772 err_object = "output";
9773 err_tag = out_iter->first;
9775 // Only pass on attributes that match in both inputs.
9776 if (!in_iter->second->matches(*(out_iter->second)))
9778 // No match. Delete the attribute.
9779 int saved_tag = out_iter->first;
9780 delete out_iter->second;
9781 out_other_attributes->erase(out_iter);
9782 out_iter = out_other_attributes->upper_bound(saved_tag);
9786 // Matched. Keep the attribute and move to the next.
9794 // Attribute numbers >=64 (mod 128) can be safely ignored. */
9795 if ((err_tag & 127) < 64)
9797 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
9798 err_object, err_tag);
9802 gold_warning(_("%s: unknown EABI object attribute %d"),
9803 err_object, err_tag);
9809 // Stub-generation methods for Target_arm.
9811 // Make a new Arm_input_section object.
9813 template<bool big_endian>
9814 Arm_input_section<big_endian>*
9815 Target_arm<big_endian>::new_arm_input_section(
9819 Section_id sid(relobj, shndx);
9821 Arm_input_section<big_endian>* arm_input_section =
9822 new Arm_input_section<big_endian>(relobj, shndx);
9823 arm_input_section->init();
9825 // Register new Arm_input_section in map for look-up.
9826 std::pair<typename Arm_input_section_map::iterator, bool> ins =
9827 this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
9829 // Make sure that it we have not created another Arm_input_section
9830 // for this input section already.
9831 gold_assert(ins.second);
9833 return arm_input_section;
9836 // Find the Arm_input_section object corresponding to the SHNDX-th input
9837 // section of RELOBJ.
9839 template<bool big_endian>
9840 Arm_input_section<big_endian>*
9841 Target_arm<big_endian>::find_arm_input_section(
9843 unsigned int shndx) const
9845 Section_id sid(relobj, shndx);
9846 typename Arm_input_section_map::const_iterator p =
9847 this->arm_input_section_map_.find(sid);
9848 return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
9851 // Make a new stub table.
9853 template<bool big_endian>
9854 Stub_table<big_endian>*
9855 Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
9857 Stub_table<big_endian>* stub_table =
9858 new Stub_table<big_endian>(owner);
9859 this->stub_tables_.push_back(stub_table);
9861 stub_table->set_address(owner->address() + owner->data_size());
9862 stub_table->set_file_offset(owner->offset() + owner->data_size());
9863 stub_table->finalize_data_size();
9868 // Scan a relocation for stub generation.
9870 template<bool big_endian>
9872 Target_arm<big_endian>::scan_reloc_for_stub(
9873 const Relocate_info<32, big_endian>* relinfo,
9874 unsigned int r_type,
9875 const Sized_symbol<32>* gsym,
9877 const Symbol_value<32>* psymval,
9878 elfcpp::Elf_types<32>::Elf_Swxword addend,
9879 Arm_address address)
9881 typedef typename Target_arm<big_endian>::Relocate Relocate;
9883 const Arm_relobj<big_endian>* arm_relobj =
9884 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
9886 bool target_is_thumb;
9887 Symbol_value<32> symval;
9890 // This is a global symbol. Determine if we use PLT and if the
9891 // final target is THUMB.
9892 if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
9894 // This uses a PLT, change the symbol value.
9895 symval.set_output_value(this->plt_section()->address()
9896 + gsym->plt_offset());
9898 target_is_thumb = false;
9900 else if (gsym->is_undefined())
9901 // There is no need to generate a stub symbol is undefined.
9906 ((gsym->type() == elfcpp::STT_ARM_TFUNC)
9907 || (gsym->type() == elfcpp::STT_FUNC
9908 && !gsym->is_undefined()
9909 && ((psymval->value(arm_relobj, 0) & 1) != 0)));
9914 // This is a local symbol. Determine if the final target is THUMB.
9915 target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
9918 // Strip LSB if this points to a THUMB target.
9919 const Arm_reloc_property* reloc_property =
9920 arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
9921 gold_assert(reloc_property != NULL);
9923 && reloc_property->uses_thumb_bit()
9924 && ((psymval->value(arm_relobj, 0) & 1) != 0))
9926 Arm_address stripped_value =
9927 psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
9928 symval.set_output_value(stripped_value);
9932 // Get the symbol value.
9933 Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
9935 // Owing to pipelining, the PC relative branches below actually skip
9936 // two instructions when the branch offset is 0.
9937 Arm_address destination;
9940 case elfcpp::R_ARM_CALL:
9941 case elfcpp::R_ARM_JUMP24:
9942 case elfcpp::R_ARM_PLT32:
9944 destination = value + addend + 8;
9946 case elfcpp::R_ARM_THM_CALL:
9947 case elfcpp::R_ARM_THM_XPC22:
9948 case elfcpp::R_ARM_THM_JUMP24:
9949 case elfcpp::R_ARM_THM_JUMP19:
9951 destination = value + addend + 4;
9957 Reloc_stub* stub = NULL;
9958 Stub_type stub_type =
9959 Reloc_stub::stub_type_for_reloc(r_type, address, destination,
9961 if (stub_type != arm_stub_none)
9963 // Try looking up an existing stub from a stub table.
9964 Stub_table<big_endian>* stub_table =
9965 arm_relobj->stub_table(relinfo->data_shndx);
9966 gold_assert(stub_table != NULL);
9968 // Locate stub by destination.
9969 Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
9971 // Create a stub if there is not one already
9972 stub = stub_table->find_reloc_stub(stub_key);
9975 // create a new stub and add it to stub table.
9976 stub = this->stub_factory().make_reloc_stub(stub_type);
9977 stub_table->add_reloc_stub(stub, stub_key);
9980 // Record the destination address.
9981 stub->set_destination_address(destination
9982 | (target_is_thumb ? 1 : 0));
9985 // For Cortex-A8, we need to record a relocation at 4K page boundary.
9986 if (this->fix_cortex_a8_
9987 && (r_type == elfcpp::R_ARM_THM_JUMP24
9988 || r_type == elfcpp::R_ARM_THM_JUMP19
9989 || r_type == elfcpp::R_ARM_THM_CALL
9990 || r_type == elfcpp::R_ARM_THM_XPC22)
9991 && (address & 0xfffU) == 0xffeU)
9993 // Found a candidate. Note we haven't checked the destination is
9994 // within 4K here: if we do so (and don't create a record) we can't
9995 // tell that a branch should have been relocated when scanning later.
9996 this->cortex_a8_relocs_info_[address] =
9997 new Cortex_a8_reloc(stub, r_type,
9998 destination | (target_is_thumb ? 1 : 0));
10002 // This function scans a relocation sections for stub generation.
10003 // The template parameter Relocate must be a class type which provides
10004 // a single function, relocate(), which implements the machine
10005 // specific part of a relocation.
10007 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
10008 // SHT_REL or SHT_RELA.
10010 // PRELOCS points to the relocation data. RELOC_COUNT is the number
10011 // of relocs. OUTPUT_SECTION is the output section.
10012 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
10013 // mapped to output offsets.
10015 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
10016 // VIEW_SIZE is the size. These refer to the input section, unless
10017 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
10018 // the output section.
10020 template<bool big_endian>
10021 template<int sh_type>
10023 Target_arm<big_endian>::scan_reloc_section_for_stubs(
10024 const Relocate_info<32, big_endian>* relinfo,
10025 const unsigned char* prelocs,
10026 size_t reloc_count,
10027 Output_section* output_section,
10028 bool needs_special_offset_handling,
10029 const unsigned char* view,
10030 elfcpp::Elf_types<32>::Elf_Addr view_address,
10033 typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
10034 const int reloc_size =
10035 Reloc_types<sh_type, 32, big_endian>::reloc_size;
10037 Arm_relobj<big_endian>* arm_object =
10038 Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
10039 unsigned int local_count = arm_object->local_symbol_count();
10041 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
10043 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
10045 Reltype reloc(prelocs);
10047 typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
10048 unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
10049 unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
10051 r_type = this->get_real_reloc_type(r_type);
10053 // Only a few relocation types need stubs.
10054 if ((r_type != elfcpp::R_ARM_CALL)
10055 && (r_type != elfcpp::R_ARM_JUMP24)
10056 && (r_type != elfcpp::R_ARM_PLT32)
10057 && (r_type != elfcpp::R_ARM_THM_CALL)
10058 && (r_type != elfcpp::R_ARM_THM_XPC22)
10059 && (r_type != elfcpp::R_ARM_THM_JUMP24)
10060 && (r_type != elfcpp::R_ARM_THM_JUMP19)
10061 && (r_type != elfcpp::R_ARM_V4BX))
10064 section_offset_type offset =
10065 convert_to_section_size_type(reloc.get_r_offset());
10067 if (needs_special_offset_handling)
10069 offset = output_section->output_offset(relinfo->object,
10070 relinfo->data_shndx,
10076 // Create a v4bx stub if --fix-v4bx-interworking is used.
10077 if (r_type == elfcpp::R_ARM_V4BX)
10079 if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
10081 // Get the BX instruction.
10082 typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
10083 const Valtype* wv =
10084 reinterpret_cast<const Valtype*>(view + offset);
10085 elfcpp::Elf_types<32>::Elf_Swxword insn =
10086 elfcpp::Swap<32, big_endian>::readval(wv);
10087 const uint32_t reg = (insn & 0xf);
10091 // Try looking up an existing stub from a stub table.
10092 Stub_table<big_endian>* stub_table =
10093 arm_object->stub_table(relinfo->data_shndx);
10094 gold_assert(stub_table != NULL);
10096 if (stub_table->find_arm_v4bx_stub(reg) == NULL)
10098 // create a new stub and add it to stub table.
10099 Arm_v4bx_stub* stub =
10100 this->stub_factory().make_arm_v4bx_stub(reg);
10101 gold_assert(stub != NULL);
10102 stub_table->add_arm_v4bx_stub(stub);
10110 Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
10111 elfcpp::Elf_types<32>::Elf_Swxword addend =
10112 stub_addend_reader(r_type, view + offset, reloc);
10114 const Sized_symbol<32>* sym;
10116 Symbol_value<32> symval;
10117 const Symbol_value<32> *psymval;
10118 if (r_sym < local_count)
10121 psymval = arm_object->local_symbol(r_sym);
10123 // If the local symbol belongs to a section we are discarding,
10124 // and that section is a debug section, try to find the
10125 // corresponding kept section and map this symbol to its
10126 // counterpart in the kept section. The symbol must not
10127 // correspond to a section we are folding.
10129 unsigned int shndx = psymval->input_shndx(&is_ordinary);
10131 && shndx != elfcpp::SHN_UNDEF
10132 && !arm_object->is_section_included(shndx)
10133 && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
10135 if (comdat_behavior == CB_UNDETERMINED)
10138 arm_object->section_name(relinfo->data_shndx);
10139 comdat_behavior = get_comdat_behavior(name.c_str());
10141 if (comdat_behavior == CB_PRETEND)
10144 typename elfcpp::Elf_types<32>::Elf_Addr value =
10145 arm_object->map_to_kept_section(shndx, &found);
10147 symval.set_output_value(value + psymval->input_value());
10149 symval.set_output_value(0);
10153 symval.set_output_value(0);
10155 symval.set_no_output_symtab_entry();
10161 const Symbol* gsym = arm_object->global_symbol(r_sym);
10162 gold_assert(gsym != NULL);
10163 if (gsym->is_forwarder())
10164 gsym = relinfo->symtab->resolve_forwards(gsym);
10166 sym = static_cast<const Sized_symbol<32>*>(gsym);
10167 if (sym->has_symtab_index())
10168 symval.set_output_symtab_index(sym->symtab_index());
10170 symval.set_no_output_symtab_entry();
10172 // We need to compute the would-be final value of this global
10174 const Symbol_table* symtab = relinfo->symtab;
10175 const Sized_symbol<32>* sized_symbol =
10176 symtab->get_sized_symbol<32>(gsym);
10177 Symbol_table::Compute_final_value_status status;
10178 Arm_address value =
10179 symtab->compute_final_value<32>(sized_symbol, &status);
10181 // Skip this if the symbol has not output section.
10182 if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
10185 symval.set_output_value(value);
10189 // If symbol is a section symbol, we don't know the actual type of
10190 // destination. Give up.
10191 if (psymval->is_section_symbol())
10194 this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
10195 addend, view_address + offset);
10199 // Scan an input section for stub generation.
10201 template<bool big_endian>
10203 Target_arm<big_endian>::scan_section_for_stubs(
10204 const Relocate_info<32, big_endian>* relinfo,
10205 unsigned int sh_type,
10206 const unsigned char* prelocs,
10207 size_t reloc_count,
10208 Output_section* output_section,
10209 bool needs_special_offset_handling,
10210 const unsigned char* view,
10211 Arm_address view_address,
10212 section_size_type view_size)
10214 if (sh_type == elfcpp::SHT_REL)
10215 this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
10220 needs_special_offset_handling,
10224 else if (sh_type == elfcpp::SHT_RELA)
10225 // We do not support RELA type relocations yet. This is provided for
10227 this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
10232 needs_special_offset_handling,
10237 gold_unreachable();
10240 // Group input sections for stub generation.
10242 // We goup input sections in an output sections so that the total size,
10243 // including any padding space due to alignment is smaller than GROUP_SIZE
10244 // unless the only input section in group is bigger than GROUP_SIZE already.
10245 // Then an ARM stub table is created to follow the last input section
10246 // in group. For each group an ARM stub table is created an is placed
10247 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
10248 // extend the group after the stub table.
10250 template<bool big_endian>
10252 Target_arm<big_endian>::group_sections(
10254 section_size_type group_size,
10255 bool stubs_always_after_branch)
10257 // Group input sections and insert stub table
10258 Layout::Section_list section_list;
10259 layout->get_allocated_sections(§ion_list);
10260 for (Layout::Section_list::const_iterator p = section_list.begin();
10261 p != section_list.end();
10264 Arm_output_section<big_endian>* output_section =
10265 Arm_output_section<big_endian>::as_arm_output_section(*p);
10266 output_section->group_sections(group_size, stubs_always_after_branch,
10271 // Relaxation hook. This is where we do stub generation.
10273 template<bool big_endian>
10275 Target_arm<big_endian>::do_relax(
10277 const Input_objects* input_objects,
10278 Symbol_table* symtab,
10281 // No need to generate stubs if this is a relocatable link.
10282 gold_assert(!parameters->options().relocatable());
10284 // If this is the first pass, we need to group input sections into
10286 bool done_exidx_fixup = false;
10289 // Determine the stub group size. The group size is the absolute
10290 // value of the parameter --stub-group-size. If --stub-group-size
10291 // is passed a negative value, we restict stubs to be always after
10292 // the stubbed branches.
10293 int32_t stub_group_size_param =
10294 parameters->options().stub_group_size();
10295 bool stubs_always_after_branch = stub_group_size_param < 0;
10296 section_size_type stub_group_size = abs(stub_group_size_param);
10298 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
10299 // page as the first half of a 32-bit branch straddling two 4K pages.
10300 // This is a crude way of enforcing that.
10301 if (this->fix_cortex_a8_)
10302 stubs_always_after_branch = true;
10304 if (stub_group_size == 1)
10307 // Thumb branch range is +-4MB has to be used as the default
10308 // maximum size (a given section can contain both ARM and Thumb
10309 // code, so the worst case has to be taken into account).
10311 // This value is 24K less than that, which allows for 2025
10312 // 12-byte stubs. If we exceed that, then we will fail to link.
10313 // The user will have to relink with an explicit group size
10315 stub_group_size = 4170000;
10318 group_sections(layout, stub_group_size, stubs_always_after_branch);
10320 // Also fix .ARM.exidx section coverage.
10321 Output_section* os = layout->find_output_section(".ARM.exidx");
10322 if (os != NULL && os->type() == elfcpp::SHT_ARM_EXIDX)
10324 Arm_output_section<big_endian>* exidx_output_section =
10325 Arm_output_section<big_endian>::as_arm_output_section(os);
10326 this->fix_exidx_coverage(layout, exidx_output_section, symtab);
10327 done_exidx_fixup = true;
10331 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
10332 // beginning of each relaxation pass, just blow away all the stubs.
10333 // Alternatively, we could selectively remove only the stubs and reloc
10334 // information for code sections that have moved since the last pass.
10335 // That would require more book-keeping.
10336 typedef typename Stub_table_list::iterator Stub_table_iterator;
10337 if (this->fix_cortex_a8_)
10339 // Clear all Cortex-A8 reloc information.
10340 for (typename Cortex_a8_relocs_info::const_iterator p =
10341 this->cortex_a8_relocs_info_.begin();
10342 p != this->cortex_a8_relocs_info_.end();
10345 this->cortex_a8_relocs_info_.clear();
10347 // Remove all Cortex-A8 stubs.
10348 for (Stub_table_iterator sp = this->stub_tables_.begin();
10349 sp != this->stub_tables_.end();
10351 (*sp)->remove_all_cortex_a8_stubs();
10354 // Scan relocs for relocation stubs
10355 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10356 op != input_objects->relobj_end();
10359 Arm_relobj<big_endian>* arm_relobj =
10360 Arm_relobj<big_endian>::as_arm_relobj(*op);
10361 arm_relobj->scan_sections_for_stubs(this, symtab, layout);
10364 // Check all stub tables to see if any of them have their data sizes
10365 // or addresses alignments changed. These are the only things that
10367 bool any_stub_table_changed = false;
10368 Unordered_set<const Output_section*> sections_needing_adjustment;
10369 for (Stub_table_iterator sp = this->stub_tables_.begin();
10370 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10373 if ((*sp)->update_data_size_and_addralign())
10375 // Update data size of stub table owner.
10376 Arm_input_section<big_endian>* owner = (*sp)->owner();
10377 uint64_t address = owner->address();
10378 off_t offset = owner->offset();
10379 owner->reset_address_and_file_offset();
10380 owner->set_address_and_file_offset(address, offset);
10382 sections_needing_adjustment.insert(owner->output_section());
10383 any_stub_table_changed = true;
10387 // Output_section_data::output_section() returns a const pointer but we
10388 // need to update output sections, so we record all output sections needing
10389 // update above and scan the sections here to find out what sections need
10391 for(Layout::Section_list::const_iterator p = layout->section_list().begin();
10392 p != layout->section_list().end();
10395 if (sections_needing_adjustment.find(*p)
10396 != sections_needing_adjustment.end())
10397 (*p)->set_section_offsets_need_adjustment();
10400 // Stop relaxation if no EXIDX fix-up and no stub table change.
10401 bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
10403 // Finalize the stubs in the last relaxation pass.
10404 if (!continue_relaxation)
10406 for (Stub_table_iterator sp = this->stub_tables_.begin();
10407 (sp != this->stub_tables_.end()) && !any_stub_table_changed;
10409 (*sp)->finalize_stubs();
10411 // Update output local symbol counts of objects if necessary.
10412 for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
10413 op != input_objects->relobj_end();
10416 Arm_relobj<big_endian>* arm_relobj =
10417 Arm_relobj<big_endian>::as_arm_relobj(*op);
10419 // Update output local symbol counts. We need to discard local
10420 // symbols defined in parts of input sections that are discarded by
10422 if (arm_relobj->output_local_symbol_count_needs_update())
10423 arm_relobj->update_output_local_symbol_count();
10427 return continue_relaxation;
10430 // Relocate a stub.
10432 template<bool big_endian>
10434 Target_arm<big_endian>::relocate_stub(
10436 const Relocate_info<32, big_endian>* relinfo,
10437 Output_section* output_section,
10438 unsigned char* view,
10439 Arm_address address,
10440 section_size_type view_size)
10443 const Stub_template* stub_template = stub->stub_template();
10444 for (size_t i = 0; i < stub_template->reloc_count(); i++)
10446 size_t reloc_insn_index = stub_template->reloc_insn_index(i);
10447 const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
10449 unsigned int r_type = insn->r_type();
10450 section_size_type reloc_offset = stub_template->reloc_offset(i);
10451 section_size_type reloc_size = insn->size();
10452 gold_assert(reloc_offset + reloc_size <= view_size);
10454 // This is the address of the stub destination.
10455 Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
10456 Symbol_value<32> symval;
10457 symval.set_output_value(target);
10459 // Synthesize a fake reloc just in case. We don't have a symbol so
10461 unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
10462 memset(reloc_buffer, 0, sizeof(reloc_buffer));
10463 elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
10464 reloc_write.put_r_offset(reloc_offset);
10465 reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
10466 elfcpp::Rel<32, big_endian> rel(reloc_buffer);
10468 relocate.relocate(relinfo, this, output_section,
10469 this->fake_relnum_for_stubs, rel, r_type,
10470 NULL, &symval, view + reloc_offset,
10471 address + reloc_offset, reloc_size);
10475 // Determine whether an object attribute tag takes an integer, a
10478 template<bool big_endian>
10480 Target_arm<big_endian>::do_attribute_arg_type(int tag) const
10482 if (tag == Object_attribute::Tag_compatibility)
10483 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10484 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
10485 else if (tag == elfcpp::Tag_nodefaults)
10486 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
10487 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
10488 else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
10489 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
10491 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
10493 return ((tag & 1) != 0
10494 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
10495 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
10498 // Reorder attributes.
10500 // The ABI defines that Tag_conformance should be emitted first, and that
10501 // Tag_nodefaults should be second (if either is defined). This sets those
10502 // two positions, and bumps up the position of all the remaining tags to
10505 template<bool big_endian>
10507 Target_arm<big_endian>::do_attributes_order(int num) const
10509 // Reorder the known object attributes in output. We want to move
10510 // Tag_conformance to position 4 and Tag_conformance to position 5
10511 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
10513 return elfcpp::Tag_conformance;
10515 return elfcpp::Tag_nodefaults;
10516 if ((num - 2) < elfcpp::Tag_nodefaults)
10518 if ((num - 1) < elfcpp::Tag_conformance)
10523 // Scan a span of THUMB code for Cortex-A8 erratum.
10525 template<bool big_endian>
10527 Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
10528 Arm_relobj<big_endian>* arm_relobj,
10529 unsigned int shndx,
10530 section_size_type span_start,
10531 section_size_type span_end,
10532 const unsigned char* view,
10533 Arm_address address)
10535 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
10537 // The opcode is BLX.W, BL.W, B.W, Bcc.W
10538 // The branch target is in the same 4KB region as the
10539 // first half of the branch.
10540 // The instruction before the branch is a 32-bit
10541 // length non-branch instruction.
10542 section_size_type i = span_start;
10543 bool last_was_32bit = false;
10544 bool last_was_branch = false;
10545 while (i < span_end)
10547 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10548 const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
10549 uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
10550 bool is_blx = false, is_b = false;
10551 bool is_bl = false, is_bcc = false;
10553 bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
10556 // Load the rest of the insn (in manual-friendly order).
10557 insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
10559 // Encoding T4: B<c>.W.
10560 is_b = (insn & 0xf800d000U) == 0xf0009000U;
10561 // Encoding T1: BL<c>.W.
10562 is_bl = (insn & 0xf800d000U) == 0xf000d000U;
10563 // Encoding T2: BLX<c>.W.
10564 is_blx = (insn & 0xf800d000U) == 0xf000c000U;
10565 // Encoding T3: B<c>.W (not permitted in IT block).
10566 is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
10567 && (insn & 0x07f00000U) != 0x03800000U);
10570 bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
10572 // If this instruction is a 32-bit THUMB branch that crosses a 4K
10573 // page boundary and it follows 32-bit non-branch instruction,
10574 // we need to work around.
10575 if (is_32bit_branch
10576 && ((address + i) & 0xfffU) == 0xffeU
10578 && !last_was_branch)
10580 // Check to see if there is a relocation stub for this branch.
10581 bool force_target_arm = false;
10582 bool force_target_thumb = false;
10583 const Cortex_a8_reloc* cortex_a8_reloc = NULL;
10584 Cortex_a8_relocs_info::const_iterator p =
10585 this->cortex_a8_relocs_info_.find(address + i);
10587 if (p != this->cortex_a8_relocs_info_.end())
10589 cortex_a8_reloc = p->second;
10590 bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
10592 if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10593 && !target_is_thumb)
10594 force_target_arm = true;
10595 else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
10596 && target_is_thumb)
10597 force_target_thumb = true;
10601 Stub_type stub_type = arm_stub_none;
10603 // Check if we have an offending branch instruction.
10604 uint16_t upper_insn = (insn >> 16) & 0xffffU;
10605 uint16_t lower_insn = insn & 0xffffU;
10606 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10608 if (cortex_a8_reloc != NULL
10609 && cortex_a8_reloc->reloc_stub() != NULL)
10610 // We've already made a stub for this instruction, e.g.
10611 // it's a long branch or a Thumb->ARM stub. Assume that
10612 // stub will suffice to work around the A8 erratum (see
10613 // setting of always_after_branch above).
10617 offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
10619 stub_type = arm_stub_a8_veneer_b_cond;
10621 else if (is_b || is_bl || is_blx)
10623 offset = RelocFuncs::thumb32_branch_offset(upper_insn,
10628 stub_type = (is_blx
10629 ? arm_stub_a8_veneer_blx
10631 ? arm_stub_a8_veneer_bl
10632 : arm_stub_a8_veneer_b));
10635 if (stub_type != arm_stub_none)
10637 Arm_address pc_for_insn = address + i + 4;
10639 // The original instruction is a BL, but the target is
10640 // an ARM instruction. If we were not making a stub,
10641 // the BL would have been converted to a BLX. Use the
10642 // BLX stub instead in that case.
10643 if (this->may_use_blx() && force_target_arm
10644 && stub_type == arm_stub_a8_veneer_bl)
10646 stub_type = arm_stub_a8_veneer_blx;
10650 // Conversely, if the original instruction was
10651 // BLX but the target is Thumb mode, use the BL stub.
10652 else if (force_target_thumb
10653 && stub_type == arm_stub_a8_veneer_blx)
10655 stub_type = arm_stub_a8_veneer_bl;
10663 // If we found a relocation, use the proper destination,
10664 // not the offset in the (unrelocated) instruction.
10665 // Note this is always done if we switched the stub type above.
10666 if (cortex_a8_reloc != NULL)
10667 offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
10669 Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
10671 // Add a new stub if destination address in in the same page.
10672 if (((address + i) & ~0xfffU) == (target & ~0xfffU))
10674 Cortex_a8_stub* stub =
10675 this->stub_factory_.make_cortex_a8_stub(stub_type,
10679 Stub_table<big_endian>* stub_table =
10680 arm_relobj->stub_table(shndx);
10681 gold_assert(stub_table != NULL);
10682 stub_table->add_cortex_a8_stub(address + i, stub);
10687 i += insn_32bit ? 4 : 2;
10688 last_was_32bit = insn_32bit;
10689 last_was_branch = is_32bit_branch;
10693 // Apply the Cortex-A8 workaround.
10695 template<bool big_endian>
10697 Target_arm<big_endian>::apply_cortex_a8_workaround(
10698 const Cortex_a8_stub* stub,
10699 Arm_address stub_address,
10700 unsigned char* insn_view,
10701 Arm_address insn_address)
10703 typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
10704 Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
10705 Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
10706 Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
10707 off_t branch_offset = stub_address - (insn_address + 4);
10709 typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
10710 switch (stub->stub_template()->type())
10712 case arm_stub_a8_veneer_b_cond:
10713 gold_assert(!utils::has_overflow<21>(branch_offset));
10714 upper_insn = RelocFuncs::thumb32_cond_branch_upper(upper_insn,
10716 lower_insn = RelocFuncs::thumb32_cond_branch_lower(lower_insn,
10720 case arm_stub_a8_veneer_b:
10721 case arm_stub_a8_veneer_bl:
10722 case arm_stub_a8_veneer_blx:
10723 if ((lower_insn & 0x5000U) == 0x4000U)
10724 // For a BLX instruction, make sure that the relocation is
10725 // rounded up to a word boundary. This follows the semantics of
10726 // the instruction which specifies that bit 1 of the target
10727 // address will come from bit 1 of the base address.
10728 branch_offset = (branch_offset + 2) & ~3;
10730 // Put BRANCH_OFFSET back into the insn.
10731 gold_assert(!utils::has_overflow<25>(branch_offset));
10732 upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
10733 lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
10737 gold_unreachable();
10740 // Put the relocated value back in the object file:
10741 elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
10742 elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
10745 template<bool big_endian>
10746 class Target_selector_arm : public Target_selector
10749 Target_selector_arm()
10750 : Target_selector(elfcpp::EM_ARM, 32, big_endian,
10751 (big_endian ? "elf32-bigarm" : "elf32-littlearm"))
10755 do_instantiate_target()
10756 { return new Target_arm<big_endian>(); }
10759 // Fix .ARM.exidx section coverage.
10761 template<bool big_endian>
10763 Target_arm<big_endian>::fix_exidx_coverage(
10765 Arm_output_section<big_endian>* exidx_section,
10766 Symbol_table* symtab)
10768 // We need to look at all the input sections in output in ascending
10769 // order of of output address. We do that by building a sorted list
10770 // of output sections by addresses. Then we looks at the output sections
10771 // in order. The input sections in an output section are already sorted
10772 // by addresses within the output section.
10774 typedef std::set<Output_section*, output_section_address_less_than>
10775 Sorted_output_section_list;
10776 Sorted_output_section_list sorted_output_sections;
10777 Layout::Section_list section_list;
10778 layout->get_allocated_sections(§ion_list);
10779 for (Layout::Section_list::const_iterator p = section_list.begin();
10780 p != section_list.end();
10783 // We only care about output sections that contain executable code.
10784 if (((*p)->flags() & elfcpp::SHF_EXECINSTR) != 0)
10785 sorted_output_sections.insert(*p);
10788 // Go over the output sections in ascending order of output addresses.
10789 typedef typename Arm_output_section<big_endian>::Text_section_list
10791 Text_section_list sorted_text_sections;
10792 for(typename Sorted_output_section_list::iterator p =
10793 sorted_output_sections.begin();
10794 p != sorted_output_sections.end();
10797 Arm_output_section<big_endian>* arm_output_section =
10798 Arm_output_section<big_endian>::as_arm_output_section(*p);
10799 arm_output_section->append_text_sections_to_list(&sorted_text_sections);
10802 exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab);
10805 Target_selector_arm<false> target_selector_arm;
10806 Target_selector_arm<true> target_selector_armbe;
10808 } // End anonymous namespace.