1 // arm.cc -- arm target support for gold.
3 // Copyright 2009 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.
37 #include "parameters.h"
44 #include "copy-relocs.h"
46 #include "target-reloc.h"
47 #include "target-select.h"
51 #include "attributes.h"
58 template<bool big_endian
>
59 class Output_data_plt_arm
;
61 template<bool big_endian
>
64 template<bool big_endian
>
65 class Arm_input_section
;
67 template<bool big_endian
>
68 class Arm_output_section
;
70 template<bool big_endian
>
73 template<bool big_endian
>
77 typedef elfcpp::Elf_types
<32>::Elf_Addr Arm_address
;
79 // Maximum branch offsets for ARM, THUMB and THUMB2.
80 const int32_t ARM_MAX_FWD_BRANCH_OFFSET
= ((((1 << 23) - 1) << 2) + 8);
81 const int32_t ARM_MAX_BWD_BRANCH_OFFSET
= ((-((1 << 23) << 2)) + 8);
82 const int32_t THM_MAX_FWD_BRANCH_OFFSET
= ((1 << 22) -2 + 4);
83 const int32_t THM_MAX_BWD_BRANCH_OFFSET
= (-(1 << 22) + 4);
84 const int32_t THM2_MAX_FWD_BRANCH_OFFSET
= (((1 << 24) - 2) + 4);
85 const int32_t THM2_MAX_BWD_BRANCH_OFFSET
= (-(1 << 24) + 4);
87 // The arm target class.
89 // This is a very simple port of gold for ARM-EABI. It is intended for
90 // supporting Android only for the time being. Only these relocation types
119 // R_ARM_THM_MOVW_ABS_NC
120 // R_ARM_THM_MOVT_ABS
121 // R_ARM_MOVW_PREL_NC
123 // R_ARM_THM_MOVW_PREL_NC
124 // R_ARM_THM_MOVT_PREL
130 // - Support more relocation types as needed.
131 // - Make PLTs more flexible for different architecture features like
133 // There are probably a lot more.
135 // Instruction template class. This class is similar to the insn_sequence
136 // struct in bfd/elf32-arm.c.
141 // Types of instruction templates.
145 // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
146 // templates with class-specific semantics. Currently this is used
147 // only by the Cortex_a8_stub class for handling condition codes in
148 // conditional branches.
149 THUMB16_SPECIAL_TYPE
,
155 // Factory methods to create instruction templates in different formats.
157 static const Insn_template
158 thumb16_insn(uint32_t data
)
159 { return Insn_template(data
, THUMB16_TYPE
, elfcpp::R_ARM_NONE
, 0); }
161 // A Thumb conditional branch, in which the proper condition is inserted
162 // when we build the stub.
163 static const Insn_template
164 thumb16_bcond_insn(uint32_t data
)
165 { return Insn_template(data
, THUMB16_SPECIAL_TYPE
, elfcpp::R_ARM_NONE
, 1); }
167 static const Insn_template
168 thumb32_insn(uint32_t data
)
169 { return Insn_template(data
, THUMB32_TYPE
, elfcpp::R_ARM_NONE
, 0); }
171 static const Insn_template
172 thumb32_b_insn(uint32_t data
, int reloc_addend
)
174 return Insn_template(data
, THUMB32_TYPE
, elfcpp::R_ARM_THM_JUMP24
,
178 static const Insn_template
179 arm_insn(uint32_t data
)
180 { return Insn_template(data
, ARM_TYPE
, elfcpp::R_ARM_NONE
, 0); }
182 static const Insn_template
183 arm_rel_insn(unsigned data
, int reloc_addend
)
184 { return Insn_template(data
, ARM_TYPE
, elfcpp::R_ARM_JUMP24
, reloc_addend
); }
186 static const Insn_template
187 data_word(unsigned data
, unsigned int r_type
, int reloc_addend
)
188 { return Insn_template(data
, DATA_TYPE
, r_type
, reloc_addend
); }
190 // Accessors. This class is used for read-only objects so no modifiers
195 { return this->data_
; }
197 // Return the instruction sequence type of this.
200 { return this->type_
; }
202 // Return the ARM relocation type of this.
205 { return this->r_type_
; }
209 { return this->reloc_addend_
; }
211 // Return size of instruction template in bytes.
215 // Return byte-alignment of instruction template.
220 // We make the constructor private to ensure that only the factory
223 Insn_template(unsigned data
, Type type
, unsigned int r_type
, int reloc_addend
)
224 : data_(data
), type_(type
), r_type_(r_type
), reloc_addend_(reloc_addend
)
227 // Instruction specific data. This is used to store information like
228 // some of the instruction bits.
230 // Instruction template type.
232 // Relocation type if there is a relocation or R_ARM_NONE otherwise.
233 unsigned int r_type_
;
234 // Relocation addend.
235 int32_t reloc_addend_
;
238 // Macro for generating code to stub types. One entry per long/short
242 DEF_STUB(long_branch_any_any) \
243 DEF_STUB(long_branch_v4t_arm_thumb) \
244 DEF_STUB(long_branch_thumb_only) \
245 DEF_STUB(long_branch_v4t_thumb_thumb) \
246 DEF_STUB(long_branch_v4t_thumb_arm) \
247 DEF_STUB(short_branch_v4t_thumb_arm) \
248 DEF_STUB(long_branch_any_arm_pic) \
249 DEF_STUB(long_branch_any_thumb_pic) \
250 DEF_STUB(long_branch_v4t_thumb_thumb_pic) \
251 DEF_STUB(long_branch_v4t_arm_thumb_pic) \
252 DEF_STUB(long_branch_v4t_thumb_arm_pic) \
253 DEF_STUB(long_branch_thumb_only_pic) \
254 DEF_STUB(a8_veneer_b_cond) \
255 DEF_STUB(a8_veneer_b) \
256 DEF_STUB(a8_veneer_bl) \
257 DEF_STUB(a8_veneer_blx)
261 #define DEF_STUB(x) arm_stub_##x,
267 // First reloc stub type.
268 arm_stub_reloc_first
= arm_stub_long_branch_any_any
,
269 // Last reloc stub type.
270 arm_stub_reloc_last
= arm_stub_long_branch_thumb_only_pic
,
272 // First Cortex-A8 stub type.
273 arm_stub_cortex_a8_first
= arm_stub_a8_veneer_b_cond
,
274 // Last Cortex-A8 stub type.
275 arm_stub_cortex_a8_last
= arm_stub_a8_veneer_blx
,
278 arm_stub_type_last
= arm_stub_a8_veneer_blx
282 // Stub template class. Templates are meant to be read-only objects.
283 // A stub template for a stub type contains all read-only attributes
284 // common to all stubs of the same type.
289 Stub_template(Stub_type
, const Insn_template
*, size_t);
297 { return this->type_
; }
299 // Return an array of instruction templates.
302 { return this->insns_
; }
304 // Return size of template in number of instructions.
307 { return this->insn_count_
; }
309 // Return size of template in bytes.
312 { return this->size_
; }
314 // Return alignment of the stub template.
317 { return this->alignment_
; }
319 // Return whether entry point is in thumb mode.
321 entry_in_thumb_mode() const
322 { return this->entry_in_thumb_mode_
; }
324 // Return number of relocations in this template.
327 { return this->relocs_
.size(); }
329 // Return index of the I-th instruction with relocation.
331 reloc_insn_index(size_t i
) const
333 gold_assert(i
< this->relocs_
.size());
334 return this->relocs_
[i
].first
;
337 // Return the offset of the I-th instruction with relocation from the
338 // beginning of the stub.
340 reloc_offset(size_t i
) const
342 gold_assert(i
< this->relocs_
.size());
343 return this->relocs_
[i
].second
;
347 // This contains information about an instruction template with a relocation
348 // and its offset from start of stub.
349 typedef std::pair
<size_t, section_size_type
> Reloc
;
351 // A Stub_template may not be copied. We want to share templates as much
353 Stub_template(const Stub_template
&);
354 Stub_template
& operator=(const Stub_template
&);
358 // Points to an array of Insn_templates.
359 const Insn_template
* insns_
;
360 // Number of Insn_templates in insns_[].
362 // Size of templated instructions in bytes.
364 // Alignment of templated instructions.
366 // Flag to indicate if entry is in thumb mode.
367 bool entry_in_thumb_mode_
;
368 // A table of reloc instruction indices and offsets. We can find these by
369 // looking at the instruction templates but we pre-compute and then stash
370 // them here for speed.
371 std::vector
<Reloc
> relocs_
;
375 // A class for code stubs. This is a base class for different type of
376 // stubs used in the ARM target.
382 static const section_offset_type invalid_offset
=
383 static_cast<section_offset_type
>(-1);
386 Stub(const Stub_template
* stub_template
)
387 : stub_template_(stub_template
), offset_(invalid_offset
)
394 // Return the stub template.
396 stub_template() const
397 { return this->stub_template_
; }
399 // Return offset of code stub from beginning of its containing stub table.
403 gold_assert(this->offset_
!= invalid_offset
);
404 return this->offset_
;
407 // Set offset of code stub from beginning of its containing stub table.
409 set_offset(section_offset_type offset
)
410 { this->offset_
= offset
; }
412 // Return the relocation target address of the i-th relocation in the
413 // stub. This must be defined in a child class.
415 reloc_target(size_t i
)
416 { return this->do_reloc_target(i
); }
418 // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written.
420 write(unsigned char* view
, section_size_type view_size
, bool big_endian
)
421 { this->do_write(view
, view_size
, big_endian
); }
423 // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
424 // for the i-th instruction.
426 thumb16_special(size_t i
)
427 { return this->do_thumb16_special(i
); }
430 // This must be defined in the child class.
432 do_reloc_target(size_t) = 0;
434 // This may be overridden in the child class.
436 do_write(unsigned char* view
, section_size_type view_size
, bool big_endian
)
439 this->do_fixed_endian_write
<true>(view
, view_size
);
441 this->do_fixed_endian_write
<false>(view
, view_size
);
444 // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
445 // instruction template.
447 do_thumb16_special(size_t)
448 { gold_unreachable(); }
451 // A template to implement do_write.
452 template<bool big_endian
>
454 do_fixed_endian_write(unsigned char*, section_size_type
);
457 const Stub_template
* stub_template_
;
458 // Offset within the section of containing this stub.
459 section_offset_type offset_
;
462 // Reloc stub class. These are stubs we use to fix up relocation because
463 // of limited branch ranges.
465 class Reloc_stub
: public Stub
468 static const unsigned int invalid_index
= static_cast<unsigned int>(-1);
469 // We assume we never jump to this address.
470 static const Arm_address invalid_address
= static_cast<Arm_address
>(-1);
472 // Return destination address.
474 destination_address() const
476 gold_assert(this->destination_address_
!= this->invalid_address
);
477 return this->destination_address_
;
480 // Set destination address.
482 set_destination_address(Arm_address address
)
484 gold_assert(address
!= this->invalid_address
);
485 this->destination_address_
= address
;
488 // Reset destination address.
490 reset_destination_address()
491 { this->destination_address_
= this->invalid_address
; }
493 // Determine stub type for a branch of a relocation of R_TYPE going
494 // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set,
495 // the branch target is a thumb instruction. TARGET is used for look
496 // up ARM-specific linker settings.
498 stub_type_for_reloc(unsigned int r_type
, Arm_address branch_address
,
499 Arm_address branch_target
, bool target_is_thumb
);
501 // Reloc_stub key. A key is logically a triplet of a stub type, a symbol
502 // and an addend. Since we treat global and local symbol differently, we
503 // use a Symbol object for a global symbol and a object-index pair for
508 // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and
509 // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL
510 // and R_SYM must not be invalid_index.
511 Key(Stub_type stub_type
, const Symbol
* symbol
, const Relobj
* relobj
,
512 unsigned int r_sym
, int32_t addend
)
513 : stub_type_(stub_type
), addend_(addend
)
517 this->r_sym_
= Reloc_stub::invalid_index
;
518 this->u_
.symbol
= symbol
;
522 gold_assert(relobj
!= NULL
&& r_sym
!= invalid_index
);
523 this->r_sym_
= r_sym
;
524 this->u_
.relobj
= relobj
;
531 // Accessors: Keys are meant to be read-only object so no modifiers are
537 { return this->stub_type_
; }
539 // Return the local symbol index or invalid_index.
542 { return this->r_sym_
; }
544 // Return the symbol if there is one.
547 { return this->r_sym_
== invalid_index
? this->u_
.symbol
: NULL
; }
549 // Return the relobj if there is one.
552 { return this->r_sym_
!= invalid_index
? this->u_
.relobj
: NULL
; }
554 // Whether this equals to another key k.
556 eq(const Key
& k
) const
558 return ((this->stub_type_
== k
.stub_type_
)
559 && (this->r_sym_
== k
.r_sym_
)
560 && ((this->r_sym_
!= Reloc_stub::invalid_index
)
561 ? (this->u_
.relobj
== k
.u_
.relobj
)
562 : (this->u_
.symbol
== k
.u_
.symbol
))
563 && (this->addend_
== k
.addend_
));
566 // Return a hash value.
570 return (this->stub_type_
572 ^ gold::string_hash
<char>(
573 (this->r_sym_
!= Reloc_stub::invalid_index
)
574 ? this->u_
.relobj
->name().c_str()
575 : this->u_
.symbol
->name())
579 // Functors for STL associative containers.
583 operator()(const Key
& k
) const
584 { return k
.hash_value(); }
590 operator()(const Key
& k1
, const Key
& k2
) const
591 { return k1
.eq(k2
); }
594 // Name of key. This is mainly for debugging.
600 Stub_type stub_type_
;
601 // If this is a local symbol, this is the index in the defining object.
602 // Otherwise, it is invalid_index for a global symbol.
604 // If r_sym_ is invalid index. This points to a global symbol.
605 // Otherwise, this points a relobj. We used the unsized and target
606 // independent Symbol and Relobj classes instead of Sized_symbol<32> and
607 // Arm_relobj. This is done to avoid making the stub class a template
608 // as most of the stub machinery is endianity-neutral. However, it
609 // may require a bit of casting done by users of this class.
612 const Symbol
* symbol
;
613 const Relobj
* relobj
;
615 // Addend associated with a reloc.
620 // Reloc_stubs are created via a stub factory. So these are protected.
621 Reloc_stub(const Stub_template
* stub_template
)
622 : Stub(stub_template
), destination_address_(invalid_address
)
628 friend class Stub_factory
;
630 // Return the relocation target address of the i-th relocation in the
633 do_reloc_target(size_t i
)
635 // All reloc stub have only one relocation.
637 return this->destination_address_
;
641 // Address of destination.
642 Arm_address destination_address_
;
645 // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
646 // THUMB branch that meets the following conditions:
648 // 1. The branch straddles across a page boundary. i.e. lower 12-bit of
649 // branch address is 0xffe.
650 // 2. The branch target address is in the same page as the first word of the
652 // 3. The branch follows a 32-bit instruction which is not a branch.
654 // To do the fix up, we need to store the address of the branch instruction
655 // and its target at least. We also need to store the original branch
656 // instruction bits for the condition code in a conditional branch. The
657 // condition code is used in a special instruction template. We also want
658 // to identify input sections needing Cortex-A8 workaround quickly. We store
659 // extra information about object and section index of the code section
660 // containing a branch being fixed up. The information is used to mark
661 // the code section when we finalize the Cortex-A8 stubs.
664 class Cortex_a8_stub
: public Stub
670 // Return the object of the code section containing the branch being fixed
674 { return this->relobj_
; }
676 // Return the section index of the code section containing the branch being
680 { return this->shndx_
; }
682 // Return the source address of stub. This is the address of the original
683 // branch instruction. LSB is 1 always set to indicate that it is a THUMB
686 source_address() const
687 { return this->source_address_
; }
689 // Return the destination address of the stub. This is the branch taken
690 // address of the original branch instruction. LSB is 1 if it is a THUMB
691 // instruction address.
693 destination_address() const
694 { return this->destination_address_
; }
696 // Return the instruction being fixed up.
698 original_insn() const
699 { return this->original_insn_
; }
702 // Cortex_a8_stubs are created via a stub factory. So these are protected.
703 Cortex_a8_stub(const Stub_template
* stub_template
, Relobj
* relobj
,
704 unsigned int shndx
, Arm_address source_address
,
705 Arm_address destination_address
, uint32_t original_insn
)
706 : Stub(stub_template
), relobj_(relobj
), shndx_(shndx
),
707 source_address_(source_address
| 1U),
708 destination_address_(destination_address
),
709 original_insn_(original_insn
)
712 friend class Stub_factory
;
714 // Return the relocation target address of the i-th relocation in the
717 do_reloc_target(size_t i
)
719 if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond
)
721 // The conditional branch veneer has two relocations.
723 return i
== 0 ? this->source_address_
+ 4 : this->destination_address_
;
727 // All other Cortex-A8 stubs have only one relocation.
729 return this->destination_address_
;
733 // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
735 do_thumb16_special(size_t);
738 // Object of the code section containing the branch being fixed up.
740 // Section index of the code section containing the branch begin fixed up.
742 // Source address of original branch.
743 Arm_address source_address_
;
744 // Destination address of the original branch.
745 Arm_address destination_address_
;
746 // Original branch instruction. This is needed for copying the condition
747 // code from a condition branch to its stub.
748 uint32_t original_insn_
;
751 // Stub factory class.
756 // Return the unique instance of this class.
757 static const Stub_factory
&
760 static Stub_factory singleton
;
764 // Make a relocation stub.
766 make_reloc_stub(Stub_type stub_type
) const
768 gold_assert(stub_type
>= arm_stub_reloc_first
769 && stub_type
<= arm_stub_reloc_last
);
770 return new Reloc_stub(this->stub_templates_
[stub_type
]);
773 // Make a Cortex-A8 stub.
775 make_cortex_a8_stub(Stub_type stub_type
, Relobj
* relobj
, unsigned int shndx
,
776 Arm_address source
, Arm_address destination
,
777 uint32_t original_insn
) const
779 gold_assert(stub_type
>= arm_stub_cortex_a8_first
780 && stub_type
<= arm_stub_cortex_a8_last
);
781 return new Cortex_a8_stub(this->stub_templates_
[stub_type
], relobj
, shndx
,
782 source
, destination
, original_insn
);
786 // Constructor and destructor are protected since we only return a single
787 // instance created in Stub_factory::get_instance().
791 // A Stub_factory may not be copied since it is a singleton.
792 Stub_factory(const Stub_factory
&);
793 Stub_factory
& operator=(Stub_factory
&);
795 // Stub templates. These are initialized in the constructor.
796 const Stub_template
* stub_templates_
[arm_stub_type_last
+1];
799 // A class to hold stubs for the ARM target.
801 template<bool big_endian
>
802 class Stub_table
: public Output_data
805 Stub_table(Arm_input_section
<big_endian
>* owner
)
806 : Output_data(), owner_(owner
), reloc_stubs_(), cortex_a8_stubs_(),
807 prev_data_size_(0), prev_addralign_(1)
813 // Owner of this stub table.
814 Arm_input_section
<big_endian
>*
816 { return this->owner_
; }
818 // Whether this stub table is empty.
821 { return this->reloc_stubs_
.empty() && this->cortex_a8_stubs_
.empty(); }
823 // Return the current data size.
825 current_data_size() const
826 { return this->current_data_size_for_child(); }
828 // Add a STUB with using KEY. Caller is reponsible for avoid adding
829 // if already a STUB with the same key has been added.
831 add_reloc_stub(Reloc_stub
* stub
, const Reloc_stub::Key
& key
)
833 const Stub_template
* stub_template
= stub
->stub_template();
834 gold_assert(stub_template
->type() == key
.stub_type());
835 this->reloc_stubs_
[key
] = stub
;
838 // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
839 // Caller is reponsible for avoid adding if already a STUB with the same
840 // address has been added.
842 add_cortex_a8_stub(Arm_address address
, Cortex_a8_stub
* stub
)
844 std::pair
<Arm_address
, Cortex_a8_stub
*> value(address
, stub
);
845 this->cortex_a8_stubs_
.insert(value
);
848 // Remove all Cortex-A8 stubs.
850 remove_all_cortex_a8_stubs();
852 // Look up a relocation stub using KEY. Return NULL if there is none.
854 find_reloc_stub(const Reloc_stub::Key
& key
) const
856 typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.find(key
);
857 return (p
!= this->reloc_stubs_
.end()) ? p
->second
: NULL
;
860 // Relocate stubs in this stub table.
862 relocate_stubs(const Relocate_info
<32, big_endian
>*,
863 Target_arm
<big_endian
>*, Output_section
*,
864 unsigned char*, Arm_address
, section_size_type
);
866 // Update data size and alignment at the end of a relaxation pass. Return
867 // true if either data size or alignment is different from that of the
868 // previous relaxation pass.
870 update_data_size_and_addralign();
872 // Finalize stubs. Set the offsets of all stubs and mark input sections
873 // needing the Cortex-A8 workaround.
877 // Apply Cortex-A8 workaround to an address range.
879 apply_cortex_a8_workaround_to_address_range(Target_arm
<big_endian
>*,
880 unsigned char*, Arm_address
,
884 // Write out section contents.
886 do_write(Output_file
*);
888 // Return the required alignment.
891 { return this->prev_addralign_
; }
893 // Reset address and file offset.
895 do_reset_address_and_file_offset()
896 { this->set_current_data_size_for_child(this->prev_data_size_
); }
898 // Set final data size.
900 set_final_data_size()
901 { this->set_data_size(this->current_data_size()); }
904 // Relocate one stub.
906 relocate_stub(Stub
*, const Relocate_info
<32, big_endian
>*,
907 Target_arm
<big_endian
>*, Output_section
*,
908 unsigned char*, Arm_address
, section_size_type
);
910 // Unordered map of relocation stubs.
912 Unordered_map
<Reloc_stub::Key
, Reloc_stub
*, Reloc_stub::Key::hash
,
913 Reloc_stub::Key::equal_to
>
916 // List of Cortex-A8 stubs ordered by addresses of branches being
917 // fixed up in output.
918 typedef std::map
<Arm_address
, Cortex_a8_stub
*> Cortex_a8_stub_list
;
920 // Owner of this stub table.
921 Arm_input_section
<big_endian
>* owner_
;
922 // The relocation stubs.
923 Reloc_stub_map reloc_stubs_
;
924 // The cortex_a8_stubs.
925 Cortex_a8_stub_list cortex_a8_stubs_
;
926 // data size of this in the previous pass.
927 off_t prev_data_size_
;
928 // address alignment of this in the previous pass.
929 uint64_t prev_addralign_
;
932 // A class to wrap an ordinary input section containing executable code.
934 template<bool big_endian
>
935 class Arm_input_section
: public Output_relaxed_input_section
938 Arm_input_section(Relobj
* relobj
, unsigned int shndx
)
939 : Output_relaxed_input_section(relobj
, shndx
, 1),
940 original_addralign_(1), original_size_(0), stub_table_(NULL
)
950 // Whether this is a stub table owner.
952 is_stub_table_owner() const
953 { return this->stub_table_
!= NULL
&& this->stub_table_
->owner() == this; }
955 // Return the stub table.
956 Stub_table
<big_endian
>*
958 { return this->stub_table_
; }
960 // Set the stub_table.
962 set_stub_table(Stub_table
<big_endian
>* stub_table
)
963 { this->stub_table_
= stub_table
; }
965 // Downcast a base pointer to an Arm_input_section pointer. This is
966 // not type-safe but we only use Arm_input_section not the base class.
967 static Arm_input_section
<big_endian
>*
968 as_arm_input_section(Output_relaxed_input_section
* poris
)
969 { return static_cast<Arm_input_section
<big_endian
>*>(poris
); }
972 // Write data to output file.
974 do_write(Output_file
*);
976 // Return required alignment of this.
980 if (this->is_stub_table_owner())
981 return std::max(this->stub_table_
->addralign(),
982 this->original_addralign_
);
984 return this->original_addralign_
;
987 // Finalize data size.
989 set_final_data_size();
991 // Reset address and file offset.
993 do_reset_address_and_file_offset();
997 do_output_offset(const Relobj
* object
, unsigned int shndx
,
998 section_offset_type offset
,
999 section_offset_type
* poutput
) const
1001 if ((object
== this->relobj())
1002 && (shndx
== this->shndx())
1004 && (convert_types
<uint64_t, section_offset_type
>(offset
)
1005 <= this->original_size_
))
1015 // Copying is not allowed.
1016 Arm_input_section(const Arm_input_section
&);
1017 Arm_input_section
& operator=(const Arm_input_section
&);
1019 // Address alignment of the original input section.
1020 uint64_t original_addralign_
;
1021 // Section size of the original input section.
1022 uint64_t original_size_
;
1024 Stub_table
<big_endian
>* stub_table_
;
1027 // Arm output section class. This is defined mainly to add a number of
1028 // stub generation methods.
1030 template<bool big_endian
>
1031 class Arm_output_section
: public Output_section
1034 Arm_output_section(const char* name
, elfcpp::Elf_Word type
,
1035 elfcpp::Elf_Xword flags
)
1036 : Output_section(name
, type
, flags
)
1039 ~Arm_output_section()
1042 // Group input sections for stub generation.
1044 group_sections(section_size_type
, bool, Target_arm
<big_endian
>*);
1046 // Downcast a base pointer to an Arm_output_section pointer. This is
1047 // not type-safe but we only use Arm_output_section not the base class.
1048 static Arm_output_section
<big_endian
>*
1049 as_arm_output_section(Output_section
* os
)
1050 { return static_cast<Arm_output_section
<big_endian
>*>(os
); }
1054 typedef Output_section::Input_section Input_section
;
1055 typedef Output_section::Input_section_list Input_section_list
;
1057 // Create a stub group.
1058 void create_stub_group(Input_section_list::const_iterator
,
1059 Input_section_list::const_iterator
,
1060 Input_section_list::const_iterator
,
1061 Target_arm
<big_endian
>*,
1062 std::vector
<Output_relaxed_input_section
*>*);
1065 // Arm_relobj class.
1067 template<bool big_endian
>
1068 class Arm_relobj
: public Sized_relobj
<32, big_endian
>
1071 static const Arm_address invalid_address
= static_cast<Arm_address
>(-1);
1073 Arm_relobj(const std::string
& name
, Input_file
* input_file
, off_t offset
,
1074 const typename
elfcpp::Ehdr
<32, big_endian
>& ehdr
)
1075 : Sized_relobj
<32, big_endian
>(name
, input_file
, offset
, ehdr
),
1076 stub_tables_(), local_symbol_is_thumb_function_(),
1077 attributes_section_data_(NULL
), mapping_symbols_info_(),
1078 section_has_cortex_a8_workaround_(NULL
)
1082 { delete this->attributes_section_data_
; }
1084 // Return the stub table of the SHNDX-th section if there is one.
1085 Stub_table
<big_endian
>*
1086 stub_table(unsigned int shndx
) const
1088 gold_assert(shndx
< this->stub_tables_
.size());
1089 return this->stub_tables_
[shndx
];
1092 // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
1094 set_stub_table(unsigned int shndx
, Stub_table
<big_endian
>* stub_table
)
1096 gold_assert(shndx
< this->stub_tables_
.size());
1097 this->stub_tables_
[shndx
] = stub_table
;
1100 // Whether a local symbol is a THUMB function. R_SYM is the symbol table
1101 // index. This is only valid after do_count_local_symbol is called.
1103 local_symbol_is_thumb_function(unsigned int r_sym
) const
1105 gold_assert(r_sym
< this->local_symbol_is_thumb_function_
.size());
1106 return this->local_symbol_is_thumb_function_
[r_sym
];
1109 // Scan all relocation sections for stub generation.
1111 scan_sections_for_stubs(Target_arm
<big_endian
>*, const Symbol_table
*,
1114 // Convert regular input section with index SHNDX to a relaxed section.
1116 convert_input_section_to_relaxed_section(unsigned shndx
)
1118 // The stubs have relocations and we need to process them after writing
1119 // out the stubs. So relocation now must follow section write.
1120 this->invalidate_section_offset(shndx
);
1121 this->set_relocs_must_follow_section_writes();
1124 // Downcast a base pointer to an Arm_relobj pointer. This is
1125 // not type-safe but we only use Arm_relobj not the base class.
1126 static Arm_relobj
<big_endian
>*
1127 as_arm_relobj(Relobj
* relobj
)
1128 { return static_cast<Arm_relobj
<big_endian
>*>(relobj
); }
1130 // Processor-specific flags in ELF file header. This is valid only after
1133 processor_specific_flags() const
1134 { return this->processor_specific_flags_
; }
1136 // Attribute section data This is the contents of the .ARM.attribute section
1138 const Attributes_section_data
*
1139 attributes_section_data() const
1140 { return this->attributes_section_data_
; }
1142 // Mapping symbol location.
1143 typedef std::pair
<unsigned int, Arm_address
> Mapping_symbol_position
;
1145 // Functor for STL container.
1146 struct Mapping_symbol_position_less
1149 operator()(const Mapping_symbol_position
& p1
,
1150 const Mapping_symbol_position
& p2
) const
1152 return (p1
.first
< p2
.first
1153 || (p1
.first
== p2
.first
&& p1
.second
< p2
.second
));
1157 // We only care about the first character of a mapping symbol, so
1158 // we only store that instead of the whole symbol name.
1159 typedef std::map
<Mapping_symbol_position
, char,
1160 Mapping_symbol_position_less
> Mapping_symbols_info
;
1162 // Whether a section contains any Cortex-A8 workaround.
1164 section_has_cortex_a8_workaround(unsigned int shndx
) const
1166 return (this->section_has_cortex_a8_workaround_
!= NULL
1167 && (*this->section_has_cortex_a8_workaround_
)[shndx
]);
1170 // Mark a section that has Cortex-A8 workaround.
1172 mark_section_for_cortex_a8_workaround(unsigned int shndx
)
1174 if (this->section_has_cortex_a8_workaround_
== NULL
)
1175 this->section_has_cortex_a8_workaround_
=
1176 new std::vector
<bool>(this->shnum(), false);
1177 (*this->section_has_cortex_a8_workaround_
)[shndx
] = true;
1181 // Post constructor setup.
1185 // Call parent's setup method.
1186 Sized_relobj
<32, big_endian
>::do_setup();
1188 // Initialize look-up tables.
1189 Stub_table_list
empty_stub_table_list(this->shnum(), NULL
);
1190 this->stub_tables_
.swap(empty_stub_table_list
);
1193 // Count the local symbols.
1195 do_count_local_symbols(Stringpool_template
<char>*,
1196 Stringpool_template
<char>*);
1199 do_relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
1200 const unsigned char* pshdrs
,
1201 typename Sized_relobj
<32, big_endian
>::Views
* pivews
);
1203 // Read the symbol information.
1205 do_read_symbols(Read_symbols_data
* sd
);
1207 // Process relocs for garbage collection.
1209 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
1213 // Whether a section needs to be scanned for relocation stubs.
1215 section_needs_reloc_stub_scanning(const elfcpp::Shdr
<32, big_endian
>&,
1216 const Relobj::Output_sections
&,
1217 const Symbol_table
*);
1219 // Whether a section needs to be scanned for the Cortex-A8 erratum.
1221 section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr
<32, big_endian
>&,
1222 unsigned int, Output_section
*,
1223 const Symbol_table
*);
1225 // Scan a section for the Cortex-A8 erratum.
1227 scan_section_for_cortex_a8_erratum(const elfcpp::Shdr
<32, big_endian
>&,
1228 unsigned int, Output_section
*,
1229 Target_arm
<big_endian
>*);
1231 // List of stub tables.
1232 typedef std::vector
<Stub_table
<big_endian
>*> Stub_table_list
;
1233 Stub_table_list stub_tables_
;
1234 // Bit vector to tell if a local symbol is a thumb function or not.
1235 // This is only valid after do_count_local_symbol is called.
1236 std::vector
<bool> local_symbol_is_thumb_function_
;
1237 // processor-specific flags in ELF file header.
1238 elfcpp::Elf_Word processor_specific_flags_
;
1239 // Object attributes if there is an .ARM.attributes section or NULL.
1240 Attributes_section_data
* attributes_section_data_
;
1241 // Mapping symbols information.
1242 Mapping_symbols_info mapping_symbols_info_
;
1243 // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
1244 std::vector
<bool>* section_has_cortex_a8_workaround_
;
1247 // Arm_dynobj class.
1249 template<bool big_endian
>
1250 class Arm_dynobj
: public Sized_dynobj
<32, big_endian
>
1253 Arm_dynobj(const std::string
& name
, Input_file
* input_file
, off_t offset
,
1254 const elfcpp::Ehdr
<32, big_endian
>& ehdr
)
1255 : Sized_dynobj
<32, big_endian
>(name
, input_file
, offset
, ehdr
),
1256 processor_specific_flags_(0), attributes_section_data_(NULL
)
1260 { delete this->attributes_section_data_
; }
1262 // Downcast a base pointer to an Arm_relobj pointer. This is
1263 // not type-safe but we only use Arm_relobj not the base class.
1264 static Arm_dynobj
<big_endian
>*
1265 as_arm_dynobj(Dynobj
* dynobj
)
1266 { return static_cast<Arm_dynobj
<big_endian
>*>(dynobj
); }
1268 // Processor-specific flags in ELF file header. This is valid only after
1271 processor_specific_flags() const
1272 { return this->processor_specific_flags_
; }
1274 // Attributes section data.
1275 const Attributes_section_data
*
1276 attributes_section_data() const
1277 { return this->attributes_section_data_
; }
1280 // Read the symbol information.
1282 do_read_symbols(Read_symbols_data
* sd
);
1285 // processor-specific flags in ELF file header.
1286 elfcpp::Elf_Word processor_specific_flags_
;
1287 // Object attributes if there is an .ARM.attributes section or NULL.
1288 Attributes_section_data
* attributes_section_data_
;
1291 // Functor to read reloc addends during stub generation.
1293 template<int sh_type
, bool big_endian
>
1294 struct Stub_addend_reader
1296 // Return the addend for a relocation of a particular type. Depending
1297 // on whether this is a REL or RELA relocation, read the addend from a
1298 // view or from a Reloc object.
1299 elfcpp::Elf_types
<32>::Elf_Swxword
1301 unsigned int /* r_type */,
1302 const unsigned char* /* view */,
1303 const typename Reloc_types
<sh_type
,
1304 32, big_endian
>::Reloc
& /* reloc */) const;
1307 // Specialized Stub_addend_reader for SHT_REL type relocation sections.
1309 template<bool big_endian
>
1310 struct Stub_addend_reader
<elfcpp::SHT_REL
, big_endian
>
1312 elfcpp::Elf_types
<32>::Elf_Swxword
1315 const unsigned char*,
1316 const typename Reloc_types
<elfcpp::SHT_REL
, 32, big_endian
>::Reloc
&) const;
1319 // Specialized Stub_addend_reader for RELA type relocation sections.
1320 // We currently do not handle RELA type relocation sections but it is trivial
1321 // to implement the addend reader. This is provided for completeness and to
1322 // make it easier to add support for RELA relocation sections in the future.
1324 template<bool big_endian
>
1325 struct Stub_addend_reader
<elfcpp::SHT_RELA
, big_endian
>
1327 elfcpp::Elf_types
<32>::Elf_Swxword
1330 const unsigned char*,
1331 const typename Reloc_types
<elfcpp::SHT_RELA
, 32,
1332 big_endian
>::Reloc
& reloc
) const
1333 { return reloc
.get_r_addend(); }
1336 // Cortex_a8_reloc class. We keep record of relocation that may need
1337 // the Cortex-A8 erratum workaround.
1339 class Cortex_a8_reloc
1342 Cortex_a8_reloc(Reloc_stub
* reloc_stub
, unsigned r_type
,
1343 Arm_address destination
)
1344 : reloc_stub_(reloc_stub
), r_type_(r_type
), destination_(destination
)
1350 // Accessors: This is a read-only class.
1352 // Return the relocation stub associated with this relocation if there is
1356 { return this->reloc_stub_
; }
1358 // Return the relocation type.
1361 { return this->r_type_
; }
1363 // Return the destination address of the relocation. LSB stores the THUMB
1367 { return this->destination_
; }
1370 // Associated relocation stub if there is one, or NULL.
1371 const Reloc_stub
* reloc_stub_
;
1373 unsigned int r_type_
;
1374 // Destination address of this relocation. LSB is used to distinguish
1376 Arm_address destination_
;
1379 // Utilities for manipulating integers of up to 32-bits
1383 // Sign extend an n-bit unsigned integer stored in an uint32_t into
1384 // an int32_t. NO_BITS must be between 1 to 32.
1385 template<int no_bits
>
1386 static inline int32_t
1387 sign_extend(uint32_t bits
)
1389 gold_assert(no_bits
>= 0 && no_bits
<= 32);
1391 return static_cast<int32_t>(bits
);
1392 uint32_t mask
= (~((uint32_t) 0)) >> (32 - no_bits
);
1394 uint32_t top_bit
= 1U << (no_bits
- 1);
1395 int32_t as_signed
= static_cast<int32_t>(bits
);
1396 return (bits
& top_bit
) ? as_signed
+ (-top_bit
* 2) : as_signed
;
1399 // Detects overflow of an NO_BITS integer stored in a uint32_t.
1400 template<int no_bits
>
1402 has_overflow(uint32_t bits
)
1404 gold_assert(no_bits
>= 0 && no_bits
<= 32);
1407 int32_t max
= (1 << (no_bits
- 1)) - 1;
1408 int32_t min
= -(1 << (no_bits
- 1));
1409 int32_t as_signed
= static_cast<int32_t>(bits
);
1410 return as_signed
> max
|| as_signed
< min
;
1413 // Detects overflow of an NO_BITS integer stored in a uint32_t when it
1414 // fits in the given number of bits as either a signed or unsigned value.
1415 // For example, has_signed_unsigned_overflow<8> would check
1416 // -128 <= bits <= 255
1417 template<int no_bits
>
1419 has_signed_unsigned_overflow(uint32_t bits
)
1421 gold_assert(no_bits
>= 2 && no_bits
<= 32);
1424 int32_t max
= static_cast<int32_t>((1U << no_bits
) - 1);
1425 int32_t min
= -(1 << (no_bits
- 1));
1426 int32_t as_signed
= static_cast<int32_t>(bits
);
1427 return as_signed
> max
|| as_signed
< min
;
1430 // Select bits from A and B using bits in MASK. For each n in [0..31],
1431 // the n-th bit in the result is chosen from the n-th bits of A and B.
1432 // A zero selects A and a one selects B.
1433 static inline uint32_t
1434 bit_select(uint32_t a
, uint32_t b
, uint32_t mask
)
1435 { return (a
& ~mask
) | (b
& mask
); }
1438 template<bool big_endian
>
1439 class Target_arm
: public Sized_target
<32, big_endian
>
1442 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, big_endian
>
1445 // When were are relocating a stub, we pass this as the relocation number.
1446 static const size_t fake_relnum_for_stubs
= static_cast<size_t>(-1);
1449 : Sized_target
<32, big_endian
>(&arm_info
),
1450 got_(NULL
), plt_(NULL
), got_plt_(NULL
), rel_dyn_(NULL
),
1451 copy_relocs_(elfcpp::R_ARM_COPY
), dynbss_(NULL
), stub_tables_(),
1452 stub_factory_(Stub_factory::get_instance()), may_use_blx_(false),
1453 should_force_pic_veneer_(false), arm_input_section_map_(),
1454 attributes_section_data_(NULL
), fix_cortex_a8_(false),
1455 cortex_a8_relocs_info_()
1458 // Whether we can use BLX.
1461 { return this->may_use_blx_
; }
1463 // Set use-BLX flag.
1465 set_may_use_blx(bool value
)
1466 { this->may_use_blx_
= value
; }
1468 // Whether we force PCI branch veneers.
1470 should_force_pic_veneer() const
1471 { return this->should_force_pic_veneer_
; }
1473 // Set PIC veneer flag.
1475 set_should_force_pic_veneer(bool value
)
1476 { this->should_force_pic_veneer_
= value
; }
1478 // Whether we use THUMB-2 instructions.
1480 using_thumb2() const
1482 Object_attribute
* attr
=
1483 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1484 int arch
= attr
->int_value();
1485 return arch
== elfcpp::TAG_CPU_ARCH_V6T2
|| arch
>= elfcpp::TAG_CPU_ARCH_V7
;
1488 // Whether we use THUMB/THUMB-2 instructions only.
1490 using_thumb_only() const
1492 Object_attribute
* attr
=
1493 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1494 if (attr
->int_value() != elfcpp::TAG_CPU_ARCH_V7
1495 && attr
->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M
)
1497 attr
= this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile
);
1498 return attr
->int_value() == 'M';
1501 // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
1503 may_use_arm_nop() const
1505 Object_attribute
* attr
=
1506 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1507 int arch
= attr
->int_value();
1508 return (arch
== elfcpp::TAG_CPU_ARCH_V6T2
1509 || arch
== elfcpp::TAG_CPU_ARCH_V6K
1510 || arch
== elfcpp::TAG_CPU_ARCH_V7
1511 || arch
== elfcpp::TAG_CPU_ARCH_V7E_M
);
1514 // Whether we have THUMB-2 NOP.W instruction.
1516 may_use_thumb2_nop() const
1518 Object_attribute
* attr
=
1519 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
1520 int arch
= attr
->int_value();
1521 return (arch
== elfcpp::TAG_CPU_ARCH_V6T2
1522 || arch
== elfcpp::TAG_CPU_ARCH_V7
1523 || arch
== elfcpp::TAG_CPU_ARCH_V7E_M
);
1526 // Process the relocations to determine unreferenced sections for
1527 // garbage collection.
1529 gc_process_relocs(Symbol_table
* symtab
,
1531 Sized_relobj
<32, big_endian
>* object
,
1532 unsigned int data_shndx
,
1533 unsigned int sh_type
,
1534 const unsigned char* prelocs
,
1536 Output_section
* output_section
,
1537 bool needs_special_offset_handling
,
1538 size_t local_symbol_count
,
1539 const unsigned char* plocal_symbols
);
1541 // Scan the relocations to look for symbol adjustments.
1543 scan_relocs(Symbol_table
* symtab
,
1545 Sized_relobj
<32, big_endian
>* object
,
1546 unsigned int data_shndx
,
1547 unsigned int sh_type
,
1548 const unsigned char* prelocs
,
1550 Output_section
* output_section
,
1551 bool needs_special_offset_handling
,
1552 size_t local_symbol_count
,
1553 const unsigned char* plocal_symbols
);
1555 // Finalize the sections.
1557 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
1559 // Return the value to use for a dynamic symbol which requires special
1562 do_dynsym_value(const Symbol
*) const;
1564 // Relocate a section.
1566 relocate_section(const Relocate_info
<32, big_endian
>*,
1567 unsigned int sh_type
,
1568 const unsigned char* prelocs
,
1570 Output_section
* output_section
,
1571 bool needs_special_offset_handling
,
1572 unsigned char* view
,
1573 Arm_address view_address
,
1574 section_size_type view_size
,
1575 const Reloc_symbol_changes
*);
1577 // Scan the relocs during a relocatable link.
1579 scan_relocatable_relocs(Symbol_table
* symtab
,
1581 Sized_relobj
<32, big_endian
>* object
,
1582 unsigned int data_shndx
,
1583 unsigned int sh_type
,
1584 const unsigned char* prelocs
,
1586 Output_section
* output_section
,
1587 bool needs_special_offset_handling
,
1588 size_t local_symbol_count
,
1589 const unsigned char* plocal_symbols
,
1590 Relocatable_relocs
*);
1592 // Relocate a section during a relocatable link.
1594 relocate_for_relocatable(const Relocate_info
<32, big_endian
>*,
1595 unsigned int sh_type
,
1596 const unsigned char* prelocs
,
1598 Output_section
* output_section
,
1599 off_t offset_in_output_section
,
1600 const Relocatable_relocs
*,
1601 unsigned char* view
,
1602 Arm_address view_address
,
1603 section_size_type view_size
,
1604 unsigned char* reloc_view
,
1605 section_size_type reloc_view_size
);
1607 // Return whether SYM is defined by the ABI.
1609 do_is_defined_by_abi(Symbol
* sym
) const
1610 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
1612 // Return the size of the GOT section.
1616 gold_assert(this->got_
!= NULL
);
1617 return this->got_
->data_size();
1620 // Map platform-specific reloc types
1622 get_real_reloc_type (unsigned int r_type
);
1625 // Methods to support stub-generations.
1628 // Return the stub factory
1630 stub_factory() const
1631 { return this->stub_factory_
; }
1633 // Make a new Arm_input_section object.
1634 Arm_input_section
<big_endian
>*
1635 new_arm_input_section(Relobj
*, unsigned int);
1637 // Find the Arm_input_section object corresponding to the SHNDX-th input
1638 // section of RELOBJ.
1639 Arm_input_section
<big_endian
>*
1640 find_arm_input_section(Relobj
* relobj
, unsigned int shndx
) const;
1642 // Make a new Stub_table
1643 Stub_table
<big_endian
>*
1644 new_stub_table(Arm_input_section
<big_endian
>*);
1646 // Scan a section for stub generation.
1648 scan_section_for_stubs(const Relocate_info
<32, big_endian
>*, unsigned int,
1649 const unsigned char*, size_t, Output_section
*,
1650 bool, const unsigned char*, Arm_address
,
1655 relocate_stub(Stub
*, const Relocate_info
<32, big_endian
>*,
1656 Output_section
*, unsigned char*, Arm_address
,
1659 // Get the default ARM target.
1660 static Target_arm
<big_endian
>*
1663 gold_assert(parameters
->target().machine_code() == elfcpp::EM_ARM
1664 && parameters
->target().is_big_endian() == big_endian
);
1665 return static_cast<Target_arm
<big_endian
>*>(
1666 parameters
->sized_target
<32, big_endian
>());
1669 // Whether relocation type uses LSB to distinguish THUMB addresses.
1671 reloc_uses_thumb_bit(unsigned int r_type
);
1673 // Whether NAME belongs to a mapping symbol.
1675 is_mapping_symbol_name(const char* name
)
1679 && (name
[1] == 'a' || name
[1] == 't' || name
[1] == 'd')
1680 && (name
[2] == '\0' || name
[2] == '.'));
1683 // Whether we work around the Cortex-A8 erratum.
1685 fix_cortex_a8() const
1686 { return this->fix_cortex_a8_
; }
1688 // Scan a span of THUMB code section for Cortex-A8 erratum.
1690 scan_span_for_cortex_a8_erratum(Arm_relobj
<big_endian
>*, unsigned int,
1691 section_size_type
, section_size_type
,
1692 const unsigned char*, Arm_address
);
1694 // Apply Cortex-A8 workaround to a branch.
1696 apply_cortex_a8_workaround(const Cortex_a8_stub
*, Arm_address
,
1697 unsigned char*, Arm_address
);
1700 // Make an ELF object.
1702 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
1703 const elfcpp::Ehdr
<32, big_endian
>& ehdr
);
1706 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
1707 const elfcpp::Ehdr
<32, !big_endian
>&)
1708 { gold_unreachable(); }
1711 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
1712 const elfcpp::Ehdr
<64, false>&)
1713 { gold_unreachable(); }
1716 do_make_elf_object(const std::string
&, Input_file
*, off_t
,
1717 const elfcpp::Ehdr
<64, true>&)
1718 { gold_unreachable(); }
1720 // Make an output section.
1722 do_make_output_section(const char* name
, elfcpp::Elf_Word type
,
1723 elfcpp::Elf_Xword flags
)
1724 { return new Arm_output_section
<big_endian
>(name
, type
, flags
); }
1727 do_adjust_elf_header(unsigned char* view
, int len
) const;
1729 // We only need to generate stubs, and hence perform relaxation if we are
1730 // not doing relocatable linking.
1732 do_may_relax() const
1733 { return !parameters
->options().relocatable(); }
1736 do_relax(int, const Input_objects
*, Symbol_table
*, Layout
*);
1738 // Determine whether an object attribute tag takes an integer, a
1741 do_attribute_arg_type(int tag
) const;
1743 // Reorder tags during output.
1745 do_attributes_order(int num
) const;
1748 // The class which scans relocations.
1753 : issued_non_pic_error_(false)
1757 local(Symbol_table
* symtab
, Layout
* layout
, Target_arm
* target
,
1758 Sized_relobj
<32, big_endian
>* object
,
1759 unsigned int data_shndx
,
1760 Output_section
* output_section
,
1761 const elfcpp::Rel
<32, big_endian
>& reloc
, unsigned int r_type
,
1762 const elfcpp::Sym
<32, big_endian
>& lsym
);
1765 global(Symbol_table
* symtab
, Layout
* layout
, Target_arm
* target
,
1766 Sized_relobj
<32, big_endian
>* object
,
1767 unsigned int data_shndx
,
1768 Output_section
* output_section
,
1769 const elfcpp::Rel
<32, big_endian
>& reloc
, unsigned int r_type
,
1774 unsupported_reloc_local(Sized_relobj
<32, big_endian
>*,
1775 unsigned int r_type
);
1778 unsupported_reloc_global(Sized_relobj
<32, big_endian
>*,
1779 unsigned int r_type
, Symbol
*);
1782 check_non_pic(Relobj
*, unsigned int r_type
);
1784 // Almost identical to Symbol::needs_plt_entry except that it also
1785 // handles STT_ARM_TFUNC.
1787 symbol_needs_plt_entry(const Symbol
* sym
)
1789 // An undefined symbol from an executable does not need a PLT entry.
1790 if (sym
->is_undefined() && !parameters
->options().shared())
1793 return (!parameters
->doing_static_link()
1794 && (sym
->type() == elfcpp::STT_FUNC
1795 || sym
->type() == elfcpp::STT_ARM_TFUNC
)
1796 && (sym
->is_from_dynobj()
1797 || sym
->is_undefined()
1798 || sym
->is_preemptible()));
1801 // Whether we have issued an error about a non-PIC compilation.
1802 bool issued_non_pic_error_
;
1805 // The class which implements relocation.
1815 // Return whether the static relocation needs to be applied.
1817 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1820 Output_section
* output_section
);
1822 // Do a relocation. Return false if the caller should not issue
1823 // any warnings about this relocation.
1825 relocate(const Relocate_info
<32, big_endian
>*, Target_arm
*,
1826 Output_section
*, size_t relnum
,
1827 const elfcpp::Rel
<32, big_endian
>&,
1828 unsigned int r_type
, const Sized_symbol
<32>*,
1829 const Symbol_value
<32>*,
1830 unsigned char*, Arm_address
,
1833 // Return whether we want to pass flag NON_PIC_REF for this
1834 // reloc. This means the relocation type accesses a symbol not via
1837 reloc_is_non_pic (unsigned int r_type
)
1841 // These relocation types reference GOT or PLT entries explicitly.
1842 case elfcpp::R_ARM_GOT_BREL
:
1843 case elfcpp::R_ARM_GOT_ABS
:
1844 case elfcpp::R_ARM_GOT_PREL
:
1845 case elfcpp::R_ARM_GOT_BREL12
:
1846 case elfcpp::R_ARM_PLT32_ABS
:
1847 case elfcpp::R_ARM_TLS_GD32
:
1848 case elfcpp::R_ARM_TLS_LDM32
:
1849 case elfcpp::R_ARM_TLS_IE32
:
1850 case elfcpp::R_ARM_TLS_IE12GP
:
1852 // These relocate types may use PLT entries.
1853 case elfcpp::R_ARM_CALL
:
1854 case elfcpp::R_ARM_THM_CALL
:
1855 case elfcpp::R_ARM_JUMP24
:
1856 case elfcpp::R_ARM_THM_JUMP24
:
1857 case elfcpp::R_ARM_THM_JUMP19
:
1858 case elfcpp::R_ARM_PLT32
:
1859 case elfcpp::R_ARM_THM_XPC22
:
1868 // A class which returns the size required for a relocation type,
1869 // used while scanning relocs during a relocatable link.
1870 class Relocatable_size_for_reloc
1874 get_size_for_reloc(unsigned int, Relobj
*);
1877 // Get the GOT section, creating it if necessary.
1878 Output_data_got
<32, big_endian
>*
1879 got_section(Symbol_table
*, Layout
*);
1881 // Get the GOT PLT section.
1883 got_plt_section() const
1885 gold_assert(this->got_plt_
!= NULL
);
1886 return this->got_plt_
;
1889 // Create a PLT entry for a global symbol.
1891 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
1893 // Get the PLT section.
1894 const Output_data_plt_arm
<big_endian
>*
1897 gold_assert(this->plt_
!= NULL
);
1901 // Get the dynamic reloc section, creating it if necessary.
1903 rel_dyn_section(Layout
*);
1905 // Return true if the symbol may need a COPY relocation.
1906 // References from an executable object to non-function symbols
1907 // defined in a dynamic object may need a COPY relocation.
1909 may_need_copy_reloc(Symbol
* gsym
)
1911 return (gsym
->type() != elfcpp::STT_ARM_TFUNC
1912 && gsym
->may_need_copy_reloc());
1915 // Add a potential copy relocation.
1917 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
1918 Sized_relobj
<32, big_endian
>* object
,
1919 unsigned int shndx
, Output_section
* output_section
,
1920 Symbol
* sym
, const elfcpp::Rel
<32, big_endian
>& reloc
)
1922 this->copy_relocs_
.copy_reloc(symtab
, layout
,
1923 symtab
->get_sized_symbol
<32>(sym
),
1924 object
, shndx
, output_section
, reloc
,
1925 this->rel_dyn_section(layout
));
1928 // Whether two EABI versions are compatible.
1930 are_eabi_versions_compatible(elfcpp::Elf_Word v1
, elfcpp::Elf_Word v2
);
1932 // Merge processor-specific flags from input object and those in the ELF
1933 // header of the output.
1935 merge_processor_specific_flags(const std::string
&, elfcpp::Elf_Word
);
1937 // Get the secondary compatible architecture.
1939 get_secondary_compatible_arch(const Attributes_section_data
*);
1941 // Set the secondary compatible architecture.
1943 set_secondary_compatible_arch(Attributes_section_data
*, int);
1946 tag_cpu_arch_combine(const char*, int, int*, int, int);
1948 // Helper to print AEABI enum tag value.
1950 aeabi_enum_name(unsigned int);
1952 // Return string value for TAG_CPU_name.
1954 tag_cpu_name_value(unsigned int);
1956 // Merge object attributes from input object and those in the output.
1958 merge_object_attributes(const char*, const Attributes_section_data
*);
1960 // Helper to get an AEABI object attribute
1962 get_aeabi_object_attribute(int tag
) const
1964 Attributes_section_data
* pasd
= this->attributes_section_data_
;
1965 gold_assert(pasd
!= NULL
);
1966 Object_attribute
* attr
=
1967 pasd
->get_attribute(Object_attribute::OBJ_ATTR_PROC
, tag
);
1968 gold_assert(attr
!= NULL
);
1973 // Methods to support stub-generations.
1976 // Group input sections for stub generation.
1978 group_sections(Layout
*, section_size_type
, bool);
1980 // Scan a relocation for stub generation.
1982 scan_reloc_for_stub(const Relocate_info
<32, big_endian
>*, unsigned int,
1983 const Sized_symbol
<32>*, unsigned int,
1984 const Symbol_value
<32>*,
1985 elfcpp::Elf_types
<32>::Elf_Swxword
, Arm_address
);
1987 // Scan a relocation section for stub.
1988 template<int sh_type
>
1990 scan_reloc_section_for_stubs(
1991 const Relocate_info
<32, big_endian
>* relinfo
,
1992 const unsigned char* prelocs
,
1994 Output_section
* output_section
,
1995 bool needs_special_offset_handling
,
1996 const unsigned char* view
,
1997 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2000 // Information about this specific target which we pass to the
2001 // general Target structure.
2002 static const Target::Target_info arm_info
;
2004 // The types of GOT entries needed for this platform.
2007 GOT_TYPE_STANDARD
= 0 // GOT entry for a regular symbol
2010 typedef typename
std::vector
<Stub_table
<big_endian
>*> Stub_table_list
;
2012 // Map input section to Arm_input_section.
2013 typedef Unordered_map
<Input_section_specifier
,
2014 Arm_input_section
<big_endian
>*,
2015 Input_section_specifier::hash
,
2016 Input_section_specifier::equal_to
>
2017 Arm_input_section_map
;
2019 // Map output addresses to relocs for Cortex-A8 erratum.
2020 typedef Unordered_map
<Arm_address
, const Cortex_a8_reloc
*>
2021 Cortex_a8_relocs_info
;
2024 Output_data_got
<32, big_endian
>* got_
;
2026 Output_data_plt_arm
<big_endian
>* plt_
;
2027 // The GOT PLT section.
2028 Output_data_space
* got_plt_
;
2029 // The dynamic reloc section.
2030 Reloc_section
* rel_dyn_
;
2031 // Relocs saved to avoid a COPY reloc.
2032 Copy_relocs
<elfcpp::SHT_REL
, 32, big_endian
> copy_relocs_
;
2033 // Space for variables copied with a COPY reloc.
2034 Output_data_space
* dynbss_
;
2035 // Vector of Stub_tables created.
2036 Stub_table_list stub_tables_
;
2038 const Stub_factory
&stub_factory_
;
2039 // Whether we can use BLX.
2041 // Whether we force PIC branch veneers.
2042 bool should_force_pic_veneer_
;
2043 // Map for locating Arm_input_sections.
2044 Arm_input_section_map arm_input_section_map_
;
2045 // Attributes section data in output.
2046 Attributes_section_data
* attributes_section_data_
;
2047 // Whether we want to fix code for Cortex-A8 erratum.
2048 bool fix_cortex_a8_
;
2049 // Map addresses to relocs for Cortex-A8 erratum.
2050 Cortex_a8_relocs_info cortex_a8_relocs_info_
;
2053 template<bool big_endian
>
2054 const Target::Target_info Target_arm
<big_endian
>::arm_info
=
2057 big_endian
, // is_big_endian
2058 elfcpp::EM_ARM
, // machine_code
2059 false, // has_make_symbol
2060 false, // has_resolve
2061 false, // has_code_fill
2062 true, // is_default_stack_executable
2064 "/usr/lib/libc.so.1", // dynamic_linker
2065 0x8000, // default_text_segment_address
2066 0x1000, // abi_pagesize (overridable by -z max-page-size)
2067 0x1000, // common_pagesize (overridable by -z common-page-size)
2068 elfcpp::SHN_UNDEF
, // small_common_shndx
2069 elfcpp::SHN_UNDEF
, // large_common_shndx
2070 0, // small_common_section_flags
2071 0, // large_common_section_flags
2072 ".ARM.attributes", // attributes_section
2073 "aeabi" // attributes_vendor
2076 // Arm relocate functions class
2079 template<bool big_endian
>
2080 class Arm_relocate_functions
: public Relocate_functions
<32, big_endian
>
2085 STATUS_OKAY
, // No error during relocation.
2086 STATUS_OVERFLOW
, // Relocation oveflow.
2087 STATUS_BAD_RELOC
// Relocation cannot be applied.
2091 typedef Relocate_functions
<32, big_endian
> Base
;
2092 typedef Arm_relocate_functions
<big_endian
> This
;
2094 // Encoding of imm16 argument for movt and movw ARM instructions
2097 // imm16 := imm4 | imm12
2099 // 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
2100 // +-------+---------------+-------+-------+-----------------------+
2101 // | | |imm4 | |imm12 |
2102 // +-------+---------------+-------+-------+-----------------------+
2104 // Extract the relocation addend from VAL based on the ARM
2105 // instruction encoding described above.
2106 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2107 extract_arm_movw_movt_addend(
2108 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
)
2110 // According to the Elf ABI for ARM Architecture the immediate
2111 // field is sign-extended to form the addend.
2112 return utils::sign_extend
<16>(((val
>> 4) & 0xf000) | (val
& 0xfff));
2115 // Insert X into VAL based on the ARM instruction encoding described
2117 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2118 insert_val_arm_movw_movt(
2119 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
,
2120 typename
elfcpp::Swap
<32, big_endian
>::Valtype x
)
2124 val
|= (x
& 0xf000) << 4;
2128 // Encoding of imm16 argument for movt and movw Thumb2 instructions
2131 // imm16 := imm4 | i | imm3 | imm8
2133 // 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
2134 // +---------+-+-----------+-------++-+-----+-------+---------------+
2135 // | |i| |imm4 || |imm3 | |imm8 |
2136 // +---------+-+-----------+-------++-+-----+-------+---------------+
2138 // Extract the relocation addend from VAL based on the Thumb2
2139 // instruction encoding described above.
2140 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2141 extract_thumb_movw_movt_addend(
2142 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
)
2144 // According to the Elf ABI for ARM Architecture the immediate
2145 // field is sign-extended to form the addend.
2146 return utils::sign_extend
<16>(((val
>> 4) & 0xf000)
2147 | ((val
>> 15) & 0x0800)
2148 | ((val
>> 4) & 0x0700)
2152 // Insert X into VAL based on the Thumb2 instruction encoding
2154 static inline typename
elfcpp::Swap
<32, big_endian
>::Valtype
2155 insert_val_thumb_movw_movt(
2156 typename
elfcpp::Swap
<32, big_endian
>::Valtype val
,
2157 typename
elfcpp::Swap
<32, big_endian
>::Valtype x
)
2160 val
|= (x
& 0xf000) << 4;
2161 val
|= (x
& 0x0800) << 15;
2162 val
|= (x
& 0x0700) << 4;
2163 val
|= (x
& 0x00ff);
2167 // Handle ARM long branches.
2168 static typename
This::Status
2169 arm_branch_common(unsigned int, const Relocate_info
<32, big_endian
>*,
2170 unsigned char *, const Sized_symbol
<32>*,
2171 const Arm_relobj
<big_endian
>*, unsigned int,
2172 const Symbol_value
<32>*, Arm_address
, Arm_address
, bool);
2174 // Handle THUMB long branches.
2175 static typename
This::Status
2176 thumb_branch_common(unsigned int, const Relocate_info
<32, big_endian
>*,
2177 unsigned char *, const Sized_symbol
<32>*,
2178 const Arm_relobj
<big_endian
>*, unsigned int,
2179 const Symbol_value
<32>*, Arm_address
, Arm_address
, bool);
2183 // Return the branch offset of a 32-bit THUMB branch.
2184 static inline int32_t
2185 thumb32_branch_offset(uint16_t upper_insn
, uint16_t lower_insn
)
2187 // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
2188 // involving the J1 and J2 bits.
2189 uint32_t s
= (upper_insn
& (1U << 10)) >> 10;
2190 uint32_t upper
= upper_insn
& 0x3ffU
;
2191 uint32_t lower
= lower_insn
& 0x7ffU
;
2192 uint32_t j1
= (lower_insn
& (1U << 13)) >> 13;
2193 uint32_t j2
= (lower_insn
& (1U << 11)) >> 11;
2194 uint32_t i1
= j1
^ s
? 0 : 1;
2195 uint32_t i2
= j2
^ s
? 0 : 1;
2197 return utils::sign_extend
<25>((s
<< 24) | (i1
<< 23) | (i2
<< 22)
2198 | (upper
<< 12) | (lower
<< 1));
2201 // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
2202 // UPPER_INSN is the original upper instruction of the branch. Caller is
2203 // responsible for overflow checking and BLX offset adjustment.
2204 static inline uint16_t
2205 thumb32_branch_upper(uint16_t upper_insn
, int32_t offset
)
2207 uint32_t s
= offset
< 0 ? 1 : 0;
2208 uint32_t bits
= static_cast<uint32_t>(offset
);
2209 return (upper_insn
& ~0x7ffU
) | ((bits
>> 12) & 0x3ffU
) | (s
<< 10);
2212 // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
2213 // LOWER_INSN is the original lower instruction of the branch. Caller is
2214 // responsible for overflow checking and BLX offset adjustment.
2215 static inline uint16_t
2216 thumb32_branch_lower(uint16_t lower_insn
, int32_t offset
)
2218 uint32_t s
= offset
< 0 ? 1 : 0;
2219 uint32_t bits
= static_cast<uint32_t>(offset
);
2220 return ((lower_insn
& ~0x2fffU
)
2221 | ((((bits
>> 23) & 1) ^ !s
) << 13)
2222 | ((((bits
>> 22) & 1) ^ !s
) << 11)
2223 | ((bits
>> 1) & 0x7ffU
));
2226 // Return the branch offset of a 32-bit THUMB conditional branch.
2227 static inline int32_t
2228 thumb32_cond_branch_offset(uint16_t upper_insn
, uint16_t lower_insn
)
2230 uint32_t s
= (upper_insn
& 0x0400U
) >> 10;
2231 uint32_t j1
= (lower_insn
& 0x2000U
) >> 13;
2232 uint32_t j2
= (lower_insn
& 0x0800U
) >> 11;
2233 uint32_t lower
= (lower_insn
& 0x07ffU
);
2234 uint32_t upper
= (s
<< 8) | (j2
<< 7) | (j1
<< 6) | (upper_insn
& 0x003fU
);
2236 return utils::sign_extend
<21>((upper
<< 12) | (lower
<< 1));
2239 // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
2240 // instruction. UPPER_INSN is the original upper instruction of the branch.
2241 // Caller is responsible for overflow checking.
2242 static inline uint16_t
2243 thumb32_cond_branch_upper(uint16_t upper_insn
, int32_t offset
)
2245 uint32_t s
= offset
< 0 ? 1 : 0;
2246 uint32_t bits
= static_cast<uint32_t>(offset
);
2247 return (upper_insn
& 0xfbc0U
) | (s
<< 10) | ((bits
& 0x0003f000U
) >> 12);
2250 // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
2251 // instruction. LOWER_INSN is the original lower instruction of the branch.
2252 // Caller is reponsible for overflow checking.
2253 static inline uint16_t
2254 thumb32_cond_branch_lower(uint16_t lower_insn
, int32_t offset
)
2256 uint32_t bits
= static_cast<uint32_t>(offset
);
2257 uint32_t j2
= (bits
& 0x00080000U
) >> 19;
2258 uint32_t j1
= (bits
& 0x00040000U
) >> 18;
2259 uint32_t lo
= (bits
& 0x00000ffeU
) >> 1;
2261 return (lower_insn
& 0xd000U
) | (j1
<< 13) | (j2
<< 11) | lo
;
2264 // R_ARM_ABS8: S + A
2265 static inline typename
This::Status
2266 abs8(unsigned char *view
,
2267 const Sized_relobj
<32, big_endian
>* object
,
2268 const Symbol_value
<32>* psymval
)
2270 typedef typename
elfcpp::Swap
<8, big_endian
>::Valtype Valtype
;
2271 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2272 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2273 Valtype val
= elfcpp::Swap
<8, big_endian
>::readval(wv
);
2274 Reltype addend
= utils::sign_extend
<8>(val
);
2275 Reltype x
= psymval
->value(object
, addend
);
2276 val
= utils::bit_select(val
, x
, 0xffU
);
2277 elfcpp::Swap
<8, big_endian
>::writeval(wv
, val
);
2278 return (utils::has_signed_unsigned_overflow
<8>(x
)
2279 ? This::STATUS_OVERFLOW
2280 : This::STATUS_OKAY
);
2283 // R_ARM_THM_ABS5: S + A
2284 static inline typename
This::Status
2285 thm_abs5(unsigned char *view
,
2286 const Sized_relobj
<32, big_endian
>* object
,
2287 const Symbol_value
<32>* psymval
)
2289 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2290 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2291 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2292 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2293 Reltype addend
= (val
& 0x7e0U
) >> 6;
2294 Reltype x
= psymval
->value(object
, addend
);
2295 val
= utils::bit_select(val
, x
<< 6, 0x7e0U
);
2296 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2297 return (utils::has_overflow
<5>(x
)
2298 ? This::STATUS_OVERFLOW
2299 : This::STATUS_OKAY
);
2302 // R_ARM_ABS12: S + A
2303 static inline typename
This::Status
2304 abs12(unsigned char *view
,
2305 const Sized_relobj
<32, big_endian
>* object
,
2306 const Symbol_value
<32>* psymval
)
2308 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2309 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2310 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2311 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2312 Reltype addend
= val
& 0x0fffU
;
2313 Reltype x
= psymval
->value(object
, addend
);
2314 val
= utils::bit_select(val
, x
, 0x0fffU
);
2315 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2316 return (utils::has_overflow
<12>(x
)
2317 ? This::STATUS_OVERFLOW
2318 : This::STATUS_OKAY
);
2321 // R_ARM_ABS16: S + A
2322 static inline typename
This::Status
2323 abs16(unsigned char *view
,
2324 const Sized_relobj
<32, big_endian
>* object
,
2325 const Symbol_value
<32>* psymval
)
2327 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2328 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2329 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2330 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2331 Reltype addend
= utils::sign_extend
<16>(val
);
2332 Reltype x
= psymval
->value(object
, addend
);
2333 val
= utils::bit_select(val
, x
, 0xffffU
);
2334 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2335 return (utils::has_signed_unsigned_overflow
<16>(x
)
2336 ? This::STATUS_OVERFLOW
2337 : This::STATUS_OKAY
);
2340 // R_ARM_ABS32: (S + A) | T
2341 static inline typename
This::Status
2342 abs32(unsigned char *view
,
2343 const Sized_relobj
<32, big_endian
>* object
,
2344 const Symbol_value
<32>* psymval
,
2345 Arm_address thumb_bit
)
2347 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2348 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2349 Valtype addend
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2350 Valtype x
= psymval
->value(object
, addend
) | thumb_bit
;
2351 elfcpp::Swap
<32, big_endian
>::writeval(wv
, x
);
2352 return This::STATUS_OKAY
;
2355 // R_ARM_REL32: (S + A) | T - P
2356 static inline typename
This::Status
2357 rel32(unsigned char *view
,
2358 const Sized_relobj
<32, big_endian
>* object
,
2359 const Symbol_value
<32>* psymval
,
2360 Arm_address address
,
2361 Arm_address thumb_bit
)
2363 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2364 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2365 Valtype addend
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2366 Valtype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2367 elfcpp::Swap
<32, big_endian
>::writeval(wv
, x
);
2368 return This::STATUS_OKAY
;
2371 // R_ARM_THM_CALL: (S + A) | T - P
2372 static inline typename
This::Status
2373 thm_call(const Relocate_info
<32, big_endian
>* relinfo
, unsigned char *view
,
2374 const Sized_symbol
<32>* gsym
, const Arm_relobj
<big_endian
>* object
,
2375 unsigned int r_sym
, const Symbol_value
<32>* psymval
,
2376 Arm_address address
, Arm_address thumb_bit
,
2377 bool is_weakly_undefined_without_plt
)
2379 return thumb_branch_common(elfcpp::R_ARM_THM_CALL
, relinfo
, view
, gsym
,
2380 object
, r_sym
, psymval
, address
, thumb_bit
,
2381 is_weakly_undefined_without_plt
);
2384 // R_ARM_THM_JUMP24: (S + A) | T - P
2385 static inline typename
This::Status
2386 thm_jump24(const Relocate_info
<32, big_endian
>* relinfo
, unsigned char *view
,
2387 const Sized_symbol
<32>* gsym
, const Arm_relobj
<big_endian
>* object
,
2388 unsigned int r_sym
, const Symbol_value
<32>* psymval
,
2389 Arm_address address
, Arm_address thumb_bit
,
2390 bool is_weakly_undefined_without_plt
)
2392 return thumb_branch_common(elfcpp::R_ARM_THM_JUMP24
, relinfo
, view
, gsym
,
2393 object
, r_sym
, psymval
, address
, thumb_bit
,
2394 is_weakly_undefined_without_plt
);
2397 // R_ARM_THM_JUMP24: (S + A) | T - P
2398 static typename
This::Status
2399 thm_jump19(unsigned char *view
, const Arm_relobj
<big_endian
>* object
,
2400 const Symbol_value
<32>* psymval
, Arm_address address
,
2401 Arm_address thumb_bit
);
2403 // R_ARM_THM_XPC22: (S + A) | T - P
2404 static inline typename
This::Status
2405 thm_xpc22(const Relocate_info
<32, big_endian
>* relinfo
, unsigned char *view
,
2406 const Sized_symbol
<32>* gsym
, const Arm_relobj
<big_endian
>* object
,
2407 unsigned int r_sym
, const Symbol_value
<32>* psymval
,
2408 Arm_address address
, Arm_address thumb_bit
,
2409 bool is_weakly_undefined_without_plt
)
2411 return thumb_branch_common(elfcpp::R_ARM_THM_XPC22
, relinfo
, view
, gsym
,
2412 object
, r_sym
, psymval
, address
, thumb_bit
,
2413 is_weakly_undefined_without_plt
);
2416 // R_ARM_THM_JUMP6: S + A – P
2417 static inline typename
This::Status
2418 thm_jump6(unsigned char *view
,
2419 const Sized_relobj
<32, big_endian
>* object
,
2420 const Symbol_value
<32>* psymval
,
2421 Arm_address address
)
2423 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2424 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2425 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2426 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2427 // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
2428 Reltype addend
= (((val
& 0x0200) >> 3) | ((val
& 0x00f8) >> 2));
2429 Reltype x
= (psymval
->value(object
, addend
) - address
);
2430 val
= (val
& 0xfd07) | ((x
& 0x0040) << 3) | ((val
& 0x003e) << 2);
2431 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
);
2432 // CZB does only forward jumps.
2433 return ((x
> 0x007e)
2434 ? This::STATUS_OVERFLOW
2435 : This::STATUS_OKAY
);
2438 // R_ARM_THM_JUMP8: S + A – P
2439 static inline typename
This::Status
2440 thm_jump8(unsigned char *view
,
2441 const Sized_relobj
<32, big_endian
>* object
,
2442 const Symbol_value
<32>* psymval
,
2443 Arm_address address
)
2445 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2446 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2447 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2448 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2449 Reltype addend
= utils::sign_extend
<8>((val
& 0x00ff) << 1);
2450 Reltype x
= (psymval
->value(object
, addend
) - address
);
2451 elfcpp::Swap
<16, big_endian
>::writeval(wv
, (val
& 0xff00) | ((x
& 0x01fe) >> 1));
2452 return (utils::has_overflow
<8>(x
)
2453 ? This::STATUS_OVERFLOW
2454 : This::STATUS_OKAY
);
2457 // R_ARM_THM_JUMP11: S + A – P
2458 static inline typename
This::Status
2459 thm_jump11(unsigned char *view
,
2460 const Sized_relobj
<32, big_endian
>* object
,
2461 const Symbol_value
<32>* psymval
,
2462 Arm_address address
)
2464 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2465 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Reltype
;
2466 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2467 Valtype val
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2468 Reltype addend
= utils::sign_extend
<11>((val
& 0x07ff) << 1);
2469 Reltype x
= (psymval
->value(object
, addend
) - address
);
2470 elfcpp::Swap
<16, big_endian
>::writeval(wv
, (val
& 0xf800) | ((x
& 0x0ffe) >> 1));
2471 return (utils::has_overflow
<11>(x
)
2472 ? This::STATUS_OVERFLOW
2473 : This::STATUS_OKAY
);
2476 // R_ARM_BASE_PREL: B(S) + A - P
2477 static inline typename
This::Status
2478 base_prel(unsigned char* view
,
2480 Arm_address address
)
2482 Base::rel32(view
, origin
- address
);
2486 // R_ARM_BASE_ABS: B(S) + A
2487 static inline typename
This::Status
2488 base_abs(unsigned char* view
,
2491 Base::rel32(view
, origin
);
2495 // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
2496 static inline typename
This::Status
2497 got_brel(unsigned char* view
,
2498 typename
elfcpp::Swap
<32, big_endian
>::Valtype got_offset
)
2500 Base::rel32(view
, got_offset
);
2501 return This::STATUS_OKAY
;
2504 // R_ARM_GOT_PREL: GOT(S) + A - P
2505 static inline typename
This::Status
2506 got_prel(unsigned char *view
,
2507 Arm_address got_entry
,
2508 Arm_address address
)
2510 Base::rel32(view
, got_entry
- address
);
2511 return This::STATUS_OKAY
;
2514 // R_ARM_PLT32: (S + A) | T - P
2515 static inline typename
This::Status
2516 plt32(const Relocate_info
<32, big_endian
>* relinfo
,
2517 unsigned char *view
,
2518 const Sized_symbol
<32>* gsym
,
2519 const Arm_relobj
<big_endian
>* object
,
2521 const Symbol_value
<32>* psymval
,
2522 Arm_address address
,
2523 Arm_address thumb_bit
,
2524 bool is_weakly_undefined_without_plt
)
2526 return arm_branch_common(elfcpp::R_ARM_PLT32
, relinfo
, view
, gsym
,
2527 object
, r_sym
, psymval
, address
, thumb_bit
,
2528 is_weakly_undefined_without_plt
);
2531 // R_ARM_XPC25: (S + A) | T - P
2532 static inline typename
This::Status
2533 xpc25(const Relocate_info
<32, big_endian
>* relinfo
,
2534 unsigned char *view
,
2535 const Sized_symbol
<32>* gsym
,
2536 const Arm_relobj
<big_endian
>* object
,
2538 const Symbol_value
<32>* psymval
,
2539 Arm_address address
,
2540 Arm_address thumb_bit
,
2541 bool is_weakly_undefined_without_plt
)
2543 return arm_branch_common(elfcpp::R_ARM_XPC25
, relinfo
, view
, gsym
,
2544 object
, r_sym
, psymval
, address
, thumb_bit
,
2545 is_weakly_undefined_without_plt
);
2548 // R_ARM_CALL: (S + A) | T - P
2549 static inline typename
This::Status
2550 call(const Relocate_info
<32, big_endian
>* relinfo
,
2551 unsigned char *view
,
2552 const Sized_symbol
<32>* gsym
,
2553 const Arm_relobj
<big_endian
>* object
,
2555 const Symbol_value
<32>* psymval
,
2556 Arm_address address
,
2557 Arm_address thumb_bit
,
2558 bool is_weakly_undefined_without_plt
)
2560 return arm_branch_common(elfcpp::R_ARM_CALL
, relinfo
, view
, gsym
,
2561 object
, r_sym
, psymval
, address
, thumb_bit
,
2562 is_weakly_undefined_without_plt
);
2565 // R_ARM_JUMP24: (S + A) | T - P
2566 static inline typename
This::Status
2567 jump24(const Relocate_info
<32, big_endian
>* relinfo
,
2568 unsigned char *view
,
2569 const Sized_symbol
<32>* gsym
,
2570 const Arm_relobj
<big_endian
>* object
,
2572 const Symbol_value
<32>* psymval
,
2573 Arm_address address
,
2574 Arm_address thumb_bit
,
2575 bool is_weakly_undefined_without_plt
)
2577 return arm_branch_common(elfcpp::R_ARM_JUMP24
, relinfo
, view
, gsym
,
2578 object
, r_sym
, psymval
, address
, thumb_bit
,
2579 is_weakly_undefined_without_plt
);
2582 // R_ARM_PREL: (S + A) | T - P
2583 static inline typename
This::Status
2584 prel31(unsigned char *view
,
2585 const Sized_relobj
<32, big_endian
>* object
,
2586 const Symbol_value
<32>* psymval
,
2587 Arm_address address
,
2588 Arm_address thumb_bit
)
2590 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2591 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2592 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2593 Valtype addend
= utils::sign_extend
<31>(val
);
2594 Valtype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2595 val
= utils::bit_select(val
, x
, 0x7fffffffU
);
2596 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2597 return (utils::has_overflow
<31>(x
) ?
2598 This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
2601 // R_ARM_MOVW_ABS_NC: (S + A) | T
2602 static inline typename
This::Status
2603 movw_abs_nc(unsigned char *view
,
2604 const Sized_relobj
<32, big_endian
>* object
,
2605 const Symbol_value
<32>* psymval
,
2606 Arm_address thumb_bit
)
2608 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2609 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2610 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2611 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
2612 Valtype x
= psymval
->value(object
, addend
) | thumb_bit
;
2613 val
= This::insert_val_arm_movw_movt(val
, x
);
2614 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2615 return This::STATUS_OKAY
;
2618 // R_ARM_MOVT_ABS: S + A
2619 static inline typename
This::Status
2620 movt_abs(unsigned char *view
,
2621 const Sized_relobj
<32, big_endian
>* object
,
2622 const Symbol_value
<32>* psymval
)
2624 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2625 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2626 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2627 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
2628 Valtype x
= psymval
->value(object
, addend
) >> 16;
2629 val
= This::insert_val_arm_movw_movt(val
, x
);
2630 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2631 return This::STATUS_OKAY
;
2634 // R_ARM_THM_MOVW_ABS_NC: S + A | T
2635 static inline typename
This::Status
2636 thm_movw_abs_nc(unsigned char *view
,
2637 const Sized_relobj
<32, big_endian
>* object
,
2638 const Symbol_value
<32>* psymval
,
2639 Arm_address thumb_bit
)
2641 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2642 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2643 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2644 Reltype val
= ((elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
2645 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1));
2646 Reltype addend
= extract_thumb_movw_movt_addend(val
);
2647 Reltype x
= psymval
->value(object
, addend
) | thumb_bit
;
2648 val
= This::insert_val_thumb_movw_movt(val
, x
);
2649 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
2650 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
2651 return This::STATUS_OKAY
;
2654 // R_ARM_THM_MOVT_ABS: S + A
2655 static inline typename
This::Status
2656 thm_movt_abs(unsigned char *view
,
2657 const Sized_relobj
<32, big_endian
>* object
,
2658 const Symbol_value
<32>* psymval
)
2660 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2661 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2662 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2663 Reltype val
= ((elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
2664 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1));
2665 Reltype addend
= This::extract_thumb_movw_movt_addend(val
);
2666 Reltype x
= psymval
->value(object
, addend
) >> 16;
2667 val
= This::insert_val_thumb_movw_movt(val
, x
);
2668 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
2669 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
2670 return This::STATUS_OKAY
;
2673 // R_ARM_MOVW_PREL_NC: (S + A) | T - P
2674 static inline typename
This::Status
2675 movw_prel_nc(unsigned char *view
,
2676 const Sized_relobj
<32, big_endian
>* object
,
2677 const Symbol_value
<32>* psymval
,
2678 Arm_address address
,
2679 Arm_address thumb_bit
)
2681 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2682 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2683 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2684 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
2685 Valtype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2686 val
= This::insert_val_arm_movw_movt(val
, x
);
2687 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2688 return This::STATUS_OKAY
;
2691 // R_ARM_MOVT_PREL: S + A - P
2692 static inline typename
This::Status
2693 movt_prel(unsigned char *view
,
2694 const Sized_relobj
<32, big_endian
>* object
,
2695 const Symbol_value
<32>* psymval
,
2696 Arm_address address
)
2698 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2699 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2700 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2701 Valtype addend
= This::extract_arm_movw_movt_addend(val
);
2702 Valtype x
= (psymval
->value(object
, addend
) - address
) >> 16;
2703 val
= This::insert_val_arm_movw_movt(val
, x
);
2704 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2705 return This::STATUS_OKAY
;
2708 // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
2709 static inline typename
This::Status
2710 thm_movw_prel_nc(unsigned char *view
,
2711 const Sized_relobj
<32, big_endian
>* object
,
2712 const Symbol_value
<32>* psymval
,
2713 Arm_address address
,
2714 Arm_address thumb_bit
)
2716 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2717 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2718 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2719 Reltype val
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
2720 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
2721 Reltype addend
= This::extract_thumb_movw_movt_addend(val
);
2722 Reltype x
= (psymval
->value(object
, addend
) | thumb_bit
) - address
;
2723 val
= This::insert_val_thumb_movw_movt(val
, x
);
2724 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
2725 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
2726 return This::STATUS_OKAY
;
2729 // R_ARM_THM_MOVT_PREL: S + A - P
2730 static inline typename
This::Status
2731 thm_movt_prel(unsigned char *view
,
2732 const Sized_relobj
<32, big_endian
>* object
,
2733 const Symbol_value
<32>* psymval
,
2734 Arm_address address
)
2736 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2737 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Reltype
;
2738 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2739 Reltype val
= (elfcpp::Swap
<16, big_endian
>::readval(wv
) << 16)
2740 | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
2741 Reltype addend
= This::extract_thumb_movw_movt_addend(val
);
2742 Reltype x
= (psymval
->value(object
, addend
) - address
) >> 16;
2743 val
= This::insert_val_thumb_movw_movt(val
, x
);
2744 elfcpp::Swap
<16, big_endian
>::writeval(wv
, val
>> 16);
2745 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, val
& 0xffff);
2746 return This::STATUS_OKAY
;
2750 // Relocate ARM long branches. This handles relocation types
2751 // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
2752 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
2753 // undefined and we do not use PLT in this relocation. In such a case,
2754 // the branch is converted into an NOP.
2756 template<bool big_endian
>
2757 typename Arm_relocate_functions
<big_endian
>::Status
2758 Arm_relocate_functions
<big_endian
>::arm_branch_common(
2759 unsigned int r_type
,
2760 const Relocate_info
<32, big_endian
>* relinfo
,
2761 unsigned char *view
,
2762 const Sized_symbol
<32>* gsym
,
2763 const Arm_relobj
<big_endian
>* object
,
2765 const Symbol_value
<32>* psymval
,
2766 Arm_address address
,
2767 Arm_address thumb_bit
,
2768 bool is_weakly_undefined_without_plt
)
2770 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
2771 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2772 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
2774 bool insn_is_b
= (((val
>> 28) & 0xf) <= 0xe)
2775 && ((val
& 0x0f000000UL
) == 0x0a000000UL
);
2776 bool insn_is_uncond_bl
= (val
& 0xff000000UL
) == 0xeb000000UL
;
2777 bool insn_is_cond_bl
= (((val
>> 28) & 0xf) < 0xe)
2778 && ((val
& 0x0f000000UL
) == 0x0b000000UL
);
2779 bool insn_is_blx
= (val
& 0xfe000000UL
) == 0xfa000000UL
;
2780 bool insn_is_any_branch
= (val
& 0x0e000000UL
) == 0x0a000000UL
;
2782 // Check that the instruction is valid.
2783 if (r_type
== elfcpp::R_ARM_CALL
)
2785 if (!insn_is_uncond_bl
&& !insn_is_blx
)
2786 return This::STATUS_BAD_RELOC
;
2788 else if (r_type
== elfcpp::R_ARM_JUMP24
)
2790 if (!insn_is_b
&& !insn_is_cond_bl
)
2791 return This::STATUS_BAD_RELOC
;
2793 else if (r_type
== elfcpp::R_ARM_PLT32
)
2795 if (!insn_is_any_branch
)
2796 return This::STATUS_BAD_RELOC
;
2798 else if (r_type
== elfcpp::R_ARM_XPC25
)
2800 // FIXME: AAELF document IH0044C does not say much about it other
2801 // than it being obsolete.
2802 if (!insn_is_any_branch
)
2803 return This::STATUS_BAD_RELOC
;
2808 // A branch to an undefined weak symbol is turned into a jump to
2809 // the next instruction unless a PLT entry will be created.
2810 // Do the same for local undefined symbols.
2811 // The jump to the next instruction is optimized as a NOP depending
2812 // on the architecture.
2813 const Target_arm
<big_endian
>* arm_target
=
2814 Target_arm
<big_endian
>::default_target();
2815 if (is_weakly_undefined_without_plt
)
2817 Valtype cond
= val
& 0xf0000000U
;
2818 if (arm_target
->may_use_arm_nop())
2819 val
= cond
| 0x0320f000;
2821 val
= cond
| 0x01a00000; // Using pre-UAL nop: mov r0, r0.
2822 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2823 return This::STATUS_OKAY
;
2826 Valtype addend
= utils::sign_extend
<26>(val
<< 2);
2827 Valtype branch_target
= psymval
->value(object
, addend
);
2828 int32_t branch_offset
= branch_target
- address
;
2830 // We need a stub if the branch offset is too large or if we need
2832 bool may_use_blx
= arm_target
->may_use_blx();
2833 Reloc_stub
* stub
= NULL
;
2834 if ((branch_offset
> ARM_MAX_FWD_BRANCH_OFFSET
)
2835 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
)
2836 || ((thumb_bit
!= 0) && !(may_use_blx
&& r_type
== elfcpp::R_ARM_CALL
)))
2838 Stub_type stub_type
=
2839 Reloc_stub::stub_type_for_reloc(r_type
, address
, branch_target
,
2841 if (stub_type
!= arm_stub_none
)
2843 Stub_table
<big_endian
>* stub_table
=
2844 object
->stub_table(relinfo
->data_shndx
);
2845 gold_assert(stub_table
!= NULL
);
2847 Reloc_stub::Key
stub_key(stub_type
, gsym
, object
, r_sym
, addend
);
2848 stub
= stub_table
->find_reloc_stub(stub_key
);
2849 gold_assert(stub
!= NULL
);
2850 thumb_bit
= stub
->stub_template()->entry_in_thumb_mode() ? 1 : 0;
2851 branch_target
= stub_table
->address() + stub
->offset() + addend
;
2852 branch_offset
= branch_target
- address
;
2853 gold_assert((branch_offset
<= ARM_MAX_FWD_BRANCH_OFFSET
)
2854 && (branch_offset
>= ARM_MAX_BWD_BRANCH_OFFSET
));
2858 // At this point, if we still need to switch mode, the instruction
2859 // must either be a BLX or a BL that can be converted to a BLX.
2863 gold_assert(may_use_blx
&& r_type
== elfcpp::R_ARM_CALL
);
2864 val
= (val
& 0xffffff) | 0xfa000000 | ((branch_offset
& 2) << 23);
2867 val
= utils::bit_select(val
, (branch_offset
>> 2), 0xffffffUL
);
2868 elfcpp::Swap
<32, big_endian
>::writeval(wv
, val
);
2869 return (utils::has_overflow
<26>(branch_offset
)
2870 ? This::STATUS_OVERFLOW
: This::STATUS_OKAY
);
2873 // Relocate THUMB long branches. This handles relocation types
2874 // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
2875 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
2876 // undefined and we do not use PLT in this relocation. In such a case,
2877 // the branch is converted into an NOP.
2879 template<bool big_endian
>
2880 typename Arm_relocate_functions
<big_endian
>::Status
2881 Arm_relocate_functions
<big_endian
>::thumb_branch_common(
2882 unsigned int r_type
,
2883 const Relocate_info
<32, big_endian
>* relinfo
,
2884 unsigned char *view
,
2885 const Sized_symbol
<32>* gsym
,
2886 const Arm_relobj
<big_endian
>* object
,
2888 const Symbol_value
<32>* psymval
,
2889 Arm_address address
,
2890 Arm_address thumb_bit
,
2891 bool is_weakly_undefined_without_plt
)
2893 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
2894 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
2895 uint32_t upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
2896 uint32_t lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
2898 // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
2900 bool is_bl_insn
= (lower_insn
& 0x1000U
) == 0x1000U
;
2901 bool is_blx_insn
= (lower_insn
& 0x1000U
) == 0x0000U
;
2903 // Check that the instruction is valid.
2904 if (r_type
== elfcpp::R_ARM_THM_CALL
)
2906 if (!is_bl_insn
&& !is_blx_insn
)
2907 return This::STATUS_BAD_RELOC
;
2909 else if (r_type
== elfcpp::R_ARM_THM_JUMP24
)
2911 // This cannot be a BLX.
2913 return This::STATUS_BAD_RELOC
;
2915 else if (r_type
== elfcpp::R_ARM_THM_XPC22
)
2917 // Check for Thumb to Thumb call.
2919 return This::STATUS_BAD_RELOC
;
2922 gold_warning(_("%s: Thumb BLX instruction targets "
2923 "thumb function '%s'."),
2924 object
->name().c_str(),
2925 (gsym
? gsym
->name() : "(local)"));
2926 // Convert BLX to BL.
2927 lower_insn
|= 0x1000U
;
2933 // A branch to an undefined weak symbol is turned into a jump to
2934 // the next instruction unless a PLT entry will be created.
2935 // The jump to the next instruction is optimized as a NOP.W for
2936 // Thumb-2 enabled architectures.
2937 const Target_arm
<big_endian
>* arm_target
=
2938 Target_arm
<big_endian
>::default_target();
2939 if (is_weakly_undefined_without_plt
)
2941 if (arm_target
->may_use_thumb2_nop())
2943 elfcpp::Swap
<16, big_endian
>::writeval(wv
, 0xf3af);
2944 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, 0x8000);
2948 elfcpp::Swap
<16, big_endian
>::writeval(wv
, 0xe000);
2949 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, 0xbf00);
2951 return This::STATUS_OKAY
;
2954 int32_t addend
= This::thumb32_branch_offset(upper_insn
, lower_insn
);
2955 Arm_address branch_target
= psymval
->value(object
, addend
);
2956 int32_t branch_offset
= branch_target
- address
;
2958 // We need a stub if the branch offset is too large or if we need
2960 bool may_use_blx
= arm_target
->may_use_blx();
2961 bool thumb2
= arm_target
->using_thumb2();
2963 && (branch_offset
> THM_MAX_FWD_BRANCH_OFFSET
2964 || (branch_offset
< THM_MAX_BWD_BRANCH_OFFSET
)))
2966 && (branch_offset
> THM2_MAX_FWD_BRANCH_OFFSET
2967 || (branch_offset
< THM2_MAX_BWD_BRANCH_OFFSET
)))
2968 || ((thumb_bit
== 0)
2969 && (((r_type
== elfcpp::R_ARM_THM_CALL
) && !may_use_blx
)
2970 || r_type
== elfcpp::R_ARM_THM_JUMP24
)))
2972 Stub_type stub_type
=
2973 Reloc_stub::stub_type_for_reloc(r_type
, address
, branch_target
,
2975 if (stub_type
!= arm_stub_none
)
2977 Stub_table
<big_endian
>* stub_table
=
2978 object
->stub_table(relinfo
->data_shndx
);
2979 gold_assert(stub_table
!= NULL
);
2981 Reloc_stub::Key
stub_key(stub_type
, gsym
, object
, r_sym
, addend
);
2982 Reloc_stub
* stub
= stub_table
->find_reloc_stub(stub_key
);
2983 gold_assert(stub
!= NULL
);
2984 thumb_bit
= stub
->stub_template()->entry_in_thumb_mode() ? 1 : 0;
2985 branch_target
= stub_table
->address() + stub
->offset() + addend
;
2986 branch_offset
= branch_target
- address
;
2990 // At this point, if we still need to switch mode, the instruction
2991 // must either be a BLX or a BL that can be converted to a BLX.
2994 gold_assert(may_use_blx
2995 && (r_type
== elfcpp::R_ARM_THM_CALL
2996 || r_type
== elfcpp::R_ARM_THM_XPC22
));
2997 // Make sure this is a BLX.
2998 lower_insn
&= ~0x1000U
;
3002 // Make sure this is a BL.
3003 lower_insn
|= 0x1000U
;
3006 if ((lower_insn
& 0x5000U
) == 0x4000U
)
3007 // For a BLX instruction, make sure that the relocation is rounded up
3008 // to a word boundary. This follows the semantics of the instruction
3009 // which specifies that bit 1 of the target address will come from bit
3010 // 1 of the base address.
3011 branch_offset
= (branch_offset
+ 2) & ~3;
3013 // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
3014 // We use the Thumb-2 encoding, which is safe even if dealing with
3015 // a Thumb-1 instruction by virtue of our overflow check above. */
3016 upper_insn
= This::thumb32_branch_upper(upper_insn
, branch_offset
);
3017 lower_insn
= This::thumb32_branch_lower(lower_insn
, branch_offset
);
3019 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
3020 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
3023 ? utils::has_overflow
<25>(branch_offset
)
3024 : utils::has_overflow
<23>(branch_offset
))
3025 ? This::STATUS_OVERFLOW
3026 : This::STATUS_OKAY
);
3029 // Relocate THUMB-2 long conditional branches.
3030 // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
3031 // undefined and we do not use PLT in this relocation. In such a case,
3032 // the branch is converted into an NOP.
3034 template<bool big_endian
>
3035 typename Arm_relocate_functions
<big_endian
>::Status
3036 Arm_relocate_functions
<big_endian
>::thm_jump19(
3037 unsigned char *view
,
3038 const Arm_relobj
<big_endian
>* object
,
3039 const Symbol_value
<32>* psymval
,
3040 Arm_address address
,
3041 Arm_address thumb_bit
)
3043 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
3044 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
3045 uint32_t upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
3046 uint32_t lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
3047 int32_t addend
= This::thumb32_cond_branch_offset(upper_insn
, lower_insn
);
3049 Arm_address branch_target
= psymval
->value(object
, addend
);
3050 int32_t branch_offset
= branch_target
- address
;
3052 // ??? Should handle interworking? GCC might someday try to
3053 // use this for tail calls.
3054 // FIXME: We do support thumb entry to PLT yet.
3057 gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
3058 return This::STATUS_BAD_RELOC
;
3061 // Put RELOCATION back into the insn.
3062 upper_insn
= This::thumb32_cond_branch_upper(upper_insn
, branch_offset
);
3063 lower_insn
= This::thumb32_cond_branch_lower(lower_insn
, branch_offset
);
3065 // Put the relocated value back in the object file:
3066 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
3067 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
3069 return (utils::has_overflow
<21>(branch_offset
)
3070 ? This::STATUS_OVERFLOW
3071 : This::STATUS_OKAY
);
3074 // Get the GOT section, creating it if necessary.
3076 template<bool big_endian
>
3077 Output_data_got
<32, big_endian
>*
3078 Target_arm
<big_endian
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
3080 if (this->got_
== NULL
)
3082 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
3084 this->got_
= new Output_data_got
<32, big_endian
>();
3087 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
3089 | elfcpp::SHF_WRITE
),
3090 this->got_
, false, true, true,
3093 // The old GNU linker creates a .got.plt section. We just
3094 // create another set of data in the .got section. Note that we
3095 // always create a PLT if we create a GOT, although the PLT
3097 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
3098 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
3100 | elfcpp::SHF_WRITE
),
3101 this->got_plt_
, false, false,
3104 // The first three entries are reserved.
3105 this->got_plt_
->set_current_data_size(3 * 4);
3107 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3108 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
3109 Symbol_table::PREDEFINED
,
3111 0, 0, elfcpp::STT_OBJECT
,
3113 elfcpp::STV_HIDDEN
, 0,
3119 // Get the dynamic reloc section, creating it if necessary.
3121 template<bool big_endian
>
3122 typename Target_arm
<big_endian
>::Reloc_section
*
3123 Target_arm
<big_endian
>::rel_dyn_section(Layout
* layout
)
3125 if (this->rel_dyn_
== NULL
)
3127 gold_assert(layout
!= NULL
);
3128 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
3129 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
3130 elfcpp::SHF_ALLOC
, this->rel_dyn_
, true,
3131 false, false, false);
3133 return this->rel_dyn_
;
3136 // Insn_template methods.
3138 // Return byte size of an instruction template.
3141 Insn_template::size() const
3143 switch (this->type())
3146 case THUMB16_SPECIAL_TYPE
:
3157 // Return alignment of an instruction template.
3160 Insn_template::alignment() const
3162 switch (this->type())
3165 case THUMB16_SPECIAL_TYPE
:
3176 // Stub_template methods.
3178 Stub_template::Stub_template(
3179 Stub_type type
, const Insn_template
* insns
,
3181 : type_(type
), insns_(insns
), insn_count_(insn_count
), alignment_(1),
3182 entry_in_thumb_mode_(false), relocs_()
3186 // Compute byte size and alignment of stub template.
3187 for (size_t i
= 0; i
< insn_count
; i
++)
3189 unsigned insn_alignment
= insns
[i
].alignment();
3190 size_t insn_size
= insns
[i
].size();
3191 gold_assert((offset
& (insn_alignment
- 1)) == 0);
3192 this->alignment_
= std::max(this->alignment_
, insn_alignment
);
3193 switch (insns
[i
].type())
3195 case Insn_template::THUMB16_TYPE
:
3196 case Insn_template::THUMB16_SPECIAL_TYPE
:
3198 this->entry_in_thumb_mode_
= true;
3201 case Insn_template::THUMB32_TYPE
:
3202 if (insns
[i
].r_type() != elfcpp::R_ARM_NONE
)
3203 this->relocs_
.push_back(Reloc(i
, offset
));
3205 this->entry_in_thumb_mode_
= true;
3208 case Insn_template::ARM_TYPE
:
3209 // Handle cases where the target is encoded within the
3211 if (insns
[i
].r_type() == elfcpp::R_ARM_JUMP24
)
3212 this->relocs_
.push_back(Reloc(i
, offset
));
3215 case Insn_template::DATA_TYPE
:
3216 // Entry point cannot be data.
3217 gold_assert(i
!= 0);
3218 this->relocs_
.push_back(Reloc(i
, offset
));
3224 offset
+= insn_size
;
3226 this->size_
= offset
;
3231 // Template to implement do_write for a specific target endianity.
3233 template<bool big_endian
>
3235 Stub::do_fixed_endian_write(unsigned char* view
, section_size_type view_size
)
3237 const Stub_template
* stub_template
= this->stub_template();
3238 const Insn_template
* insns
= stub_template
->insns();
3240 // FIXME: We do not handle BE8 encoding yet.
3241 unsigned char* pov
= view
;
3242 for (size_t i
= 0; i
< stub_template
->insn_count(); i
++)
3244 switch (insns
[i
].type())
3246 case Insn_template::THUMB16_TYPE
:
3247 elfcpp::Swap
<16, big_endian
>::writeval(pov
, insns
[i
].data() & 0xffff);
3249 case Insn_template::THUMB16_SPECIAL_TYPE
:
3250 elfcpp::Swap
<16, big_endian
>::writeval(
3252 this->thumb16_special(i
));
3254 case Insn_template::THUMB32_TYPE
:
3256 uint32_t hi
= (insns
[i
].data() >> 16) & 0xffff;
3257 uint32_t lo
= insns
[i
].data() & 0xffff;
3258 elfcpp::Swap
<16, big_endian
>::writeval(pov
, hi
);
3259 elfcpp::Swap
<16, big_endian
>::writeval(pov
+ 2, lo
);
3262 case Insn_template::ARM_TYPE
:
3263 case Insn_template::DATA_TYPE
:
3264 elfcpp::Swap
<32, big_endian
>::writeval(pov
, insns
[i
].data());
3269 pov
+= insns
[i
].size();
3271 gold_assert(static_cast<section_size_type
>(pov
- view
) == view_size
);
3274 // Reloc_stub::Key methods.
3276 // Dump a Key as a string for debugging.
3279 Reloc_stub::Key::name() const
3281 if (this->r_sym_
== invalid_index
)
3283 // Global symbol key name
3284 // <stub-type>:<symbol name>:<addend>.
3285 const std::string sym_name
= this->u_
.symbol
->name();
3286 // We need to print two hex number and two colons. So just add 100 bytes
3287 // to the symbol name size.
3288 size_t len
= sym_name
.size() + 100;
3289 char* buffer
= new char[len
];
3290 int c
= snprintf(buffer
, len
, "%d:%s:%x", this->stub_type_
,
3291 sym_name
.c_str(), this->addend_
);
3292 gold_assert(c
> 0 && c
< static_cast<int>(len
));
3294 return std::string(buffer
);
3298 // local symbol key name
3299 // <stub-type>:<object>:<r_sym>:<addend>.
3300 const size_t len
= 200;
3302 int c
= snprintf(buffer
, len
, "%d:%p:%u:%x", this->stub_type_
,
3303 this->u_
.relobj
, this->r_sym_
, this->addend_
);
3304 gold_assert(c
> 0 && c
< static_cast<int>(len
));
3305 return std::string(buffer
);
3309 // Reloc_stub methods.
3311 // Determine the type of stub needed, if any, for a relocation of R_TYPE at
3312 // LOCATION to DESTINATION.
3313 // This code is based on the arm_type_of_stub function in
3314 // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
3318 Reloc_stub::stub_type_for_reloc(
3319 unsigned int r_type
,
3320 Arm_address location
,
3321 Arm_address destination
,
3322 bool target_is_thumb
)
3324 Stub_type stub_type
= arm_stub_none
;
3326 // This is a bit ugly but we want to avoid using a templated class for
3327 // big and little endianities.
3329 bool should_force_pic_veneer
;
3332 if (parameters
->target().is_big_endian())
3334 const Target_arm
<true>* big_endian_target
=
3335 Target_arm
<true>::default_target();
3336 may_use_blx
= big_endian_target
->may_use_blx();
3337 should_force_pic_veneer
= big_endian_target
->should_force_pic_veneer();
3338 thumb2
= big_endian_target
->using_thumb2();
3339 thumb_only
= big_endian_target
->using_thumb_only();
3343 const Target_arm
<false>* little_endian_target
=
3344 Target_arm
<false>::default_target();
3345 may_use_blx
= little_endian_target
->may_use_blx();
3346 should_force_pic_veneer
= little_endian_target
->should_force_pic_veneer();
3347 thumb2
= little_endian_target
->using_thumb2();
3348 thumb_only
= little_endian_target
->using_thumb_only();
3351 int64_t branch_offset
= (int64_t)destination
- location
;
3353 if (r_type
== elfcpp::R_ARM_THM_CALL
|| r_type
== elfcpp::R_ARM_THM_JUMP24
)
3355 // Handle cases where:
3356 // - this call goes too far (different Thumb/Thumb2 max
3358 // - it's a Thumb->Arm call and blx is not available, or it's a
3359 // Thumb->Arm branch (not bl). A stub is needed in this case.
3361 && (branch_offset
> THM_MAX_FWD_BRANCH_OFFSET
3362 || (branch_offset
< THM_MAX_BWD_BRANCH_OFFSET
)))
3364 && (branch_offset
> THM2_MAX_FWD_BRANCH_OFFSET
3365 || (branch_offset
< THM2_MAX_BWD_BRANCH_OFFSET
)))
3366 || ((!target_is_thumb
)
3367 && (((r_type
== elfcpp::R_ARM_THM_CALL
) && !may_use_blx
)
3368 || (r_type
== elfcpp::R_ARM_THM_JUMP24
))))
3370 if (target_is_thumb
)
3375 stub_type
= (parameters
->options().shared()
3376 || should_force_pic_veneer
)
3379 && (r_type
== elfcpp::R_ARM_THM_CALL
))
3380 // V5T and above. Stub starts with ARM code, so
3381 // we must be able to switch mode before
3382 // reaching it, which is only possible for 'bl'
3383 // (ie R_ARM_THM_CALL relocation).
3384 ? arm_stub_long_branch_any_thumb_pic
3385 // On V4T, use Thumb code only.
3386 : arm_stub_long_branch_v4t_thumb_thumb_pic
)
3390 && (r_type
== elfcpp::R_ARM_THM_CALL
))
3391 ? arm_stub_long_branch_any_any
// V5T and above.
3392 : arm_stub_long_branch_v4t_thumb_thumb
); // V4T.
3396 stub_type
= (parameters
->options().shared()
3397 || should_force_pic_veneer
)
3398 ? arm_stub_long_branch_thumb_only_pic
// PIC stub.
3399 : arm_stub_long_branch_thumb_only
; // non-PIC stub.
3406 // FIXME: We should check that the input section is from an
3407 // object that has interwork enabled.
3409 stub_type
= (parameters
->options().shared()
3410 || should_force_pic_veneer
)
3413 && (r_type
== elfcpp::R_ARM_THM_CALL
))
3414 ? arm_stub_long_branch_any_arm_pic
// V5T and above.
3415 : arm_stub_long_branch_v4t_thumb_arm_pic
) // V4T.
3419 && (r_type
== elfcpp::R_ARM_THM_CALL
))
3420 ? arm_stub_long_branch_any_any
// V5T and above.
3421 : arm_stub_long_branch_v4t_thumb_arm
); // V4T.
3423 // Handle v4t short branches.
3424 if ((stub_type
== arm_stub_long_branch_v4t_thumb_arm
)
3425 && (branch_offset
<= THM_MAX_FWD_BRANCH_OFFSET
)
3426 && (branch_offset
>= THM_MAX_BWD_BRANCH_OFFSET
))
3427 stub_type
= arm_stub_short_branch_v4t_thumb_arm
;
3431 else if (r_type
== elfcpp::R_ARM_CALL
3432 || r_type
== elfcpp::R_ARM_JUMP24
3433 || r_type
== elfcpp::R_ARM_PLT32
)
3435 if (target_is_thumb
)
3439 // FIXME: We should check that the input section is from an
3440 // object that has interwork enabled.
3442 // We have an extra 2-bytes reach because of
3443 // the mode change (bit 24 (H) of BLX encoding).
3444 if (branch_offset
> (ARM_MAX_FWD_BRANCH_OFFSET
+ 2)
3445 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
)
3446 || ((r_type
== elfcpp::R_ARM_CALL
) && !may_use_blx
)
3447 || (r_type
== elfcpp::R_ARM_JUMP24
)
3448 || (r_type
== elfcpp::R_ARM_PLT32
))
3450 stub_type
= (parameters
->options().shared()
3451 || should_force_pic_veneer
)
3454 ? arm_stub_long_branch_any_thumb_pic
// V5T and above.
3455 : arm_stub_long_branch_v4t_arm_thumb_pic
) // V4T stub.
3459 ? arm_stub_long_branch_any_any
// V5T and above.
3460 : arm_stub_long_branch_v4t_arm_thumb
); // V4T.
3466 if (branch_offset
> ARM_MAX_FWD_BRANCH_OFFSET
3467 || (branch_offset
< ARM_MAX_BWD_BRANCH_OFFSET
))
3469 stub_type
= (parameters
->options().shared()
3470 || should_force_pic_veneer
)
3471 ? arm_stub_long_branch_any_arm_pic
// PIC stubs.
3472 : arm_stub_long_branch_any_any
; /// non-PIC.
3480 // Cortex_a8_stub methods.
3482 // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
3483 // I is the position of the instruction template in the stub template.
3486 Cortex_a8_stub::do_thumb16_special(size_t i
)
3488 // The only use of this is to copy condition code from a conditional
3489 // branch being worked around to the corresponding conditional branch in
3491 gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
3493 uint16_t data
= this->stub_template()->insns()[i
].data();
3494 gold_assert((data
& 0xff00U
) == 0xd000U
);
3495 data
|= ((this->original_insn_
>> 22) & 0xf) << 8;
3499 // Stub_factory methods.
3501 Stub_factory::Stub_factory()
3503 // The instruction template sequences are declared as static
3504 // objects and initialized first time the constructor runs.
3506 // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
3507 // to reach the stub if necessary.
3508 static const Insn_template elf32_arm_stub_long_branch_any_any
[] =
3510 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
3511 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
3512 // dcd R_ARM_ABS32(X)
3515 // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
3517 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb
[] =
3519 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3520 Insn_template::arm_insn(0xe12fff1c), // bx ip
3521 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
3522 // dcd R_ARM_ABS32(X)
3525 // Thumb -> Thumb long branch stub. Used on M-profile architectures.
3526 static const Insn_template elf32_arm_stub_long_branch_thumb_only
[] =
3528 Insn_template::thumb16_insn(0xb401), // push {r0}
3529 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
3530 Insn_template::thumb16_insn(0x4684), // mov ip, r0
3531 Insn_template::thumb16_insn(0xbc01), // pop {r0}
3532 Insn_template::thumb16_insn(0x4760), // bx ip
3533 Insn_template::thumb16_insn(0xbf00), // nop
3534 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
3535 // dcd R_ARM_ABS32(X)
3538 // V4T Thumb -> Thumb long branch stub. Using the stack is not
3540 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb
[] =
3542 Insn_template::thumb16_insn(0x4778), // bx pc
3543 Insn_template::thumb16_insn(0x46c0), // nop
3544 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3545 Insn_template::arm_insn(0xe12fff1c), // bx ip
3546 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
3547 // dcd R_ARM_ABS32(X)
3550 // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
3552 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm
[] =
3554 Insn_template::thumb16_insn(0x4778), // bx pc
3555 Insn_template::thumb16_insn(0x46c0), // nop
3556 Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
3557 Insn_template::data_word(0, elfcpp::R_ARM_ABS32
, 0),
3558 // dcd R_ARM_ABS32(X)
3561 // V4T Thumb -> ARM short branch stub. Shorter variant of the above
3562 // one, when the destination is close enough.
3563 static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm
[] =
3565 Insn_template::thumb16_insn(0x4778), // bx pc
3566 Insn_template::thumb16_insn(0x46c0), // nop
3567 Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
3570 // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
3571 // blx to reach the stub if necessary.
3572 static const Insn_template elf32_arm_stub_long_branch_any_arm_pic
[] =
3574 Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
3575 Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
3576 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, -4),
3577 // dcd R_ARM_REL32(X-4)
3580 // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
3581 // blx to reach the stub if necessary. We can not add into pc;
3582 // it is not guaranteed to mode switch (different in ARMv6 and
3584 static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic
[] =
3586 Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
3587 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3588 Insn_template::arm_insn(0xe12fff1c), // bx ip
3589 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
3590 // dcd R_ARM_REL32(X)
3593 // V4T ARM -> ARM long branch stub, PIC.
3594 static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic
[] =
3596 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
3597 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3598 Insn_template::arm_insn(0xe12fff1c), // bx ip
3599 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
3600 // dcd R_ARM_REL32(X)
3603 // V4T Thumb -> ARM long branch stub, PIC.
3604 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic
[] =
3606 Insn_template::thumb16_insn(0x4778), // bx pc
3607 Insn_template::thumb16_insn(0x46c0), // nop
3608 Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
3609 Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
3610 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, -4),
3611 // dcd R_ARM_REL32(X)
3614 // Thumb -> Thumb long branch stub, PIC. Used on M-profile
3616 static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic
[] =
3618 Insn_template::thumb16_insn(0xb401), // push {r0}
3619 Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
3620 Insn_template::thumb16_insn(0x46fc), // mov ip, pc
3621 Insn_template::thumb16_insn(0x4484), // add ip, r0
3622 Insn_template::thumb16_insn(0xbc01), // pop {r0}
3623 Insn_template::thumb16_insn(0x4760), // bx ip
3624 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 4),
3625 // dcd R_ARM_REL32(X)
3628 // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
3630 static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic
[] =
3632 Insn_template::thumb16_insn(0x4778), // bx pc
3633 Insn_template::thumb16_insn(0x46c0), // nop
3634 Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
3635 Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
3636 Insn_template::arm_insn(0xe12fff1c), // bx ip
3637 Insn_template::data_word(0, elfcpp::R_ARM_REL32
, 0),
3638 // dcd R_ARM_REL32(X)
3641 // Cortex-A8 erratum-workaround stubs.
3643 // Stub used for conditional branches (which may be beyond +/-1MB away,
3644 // so we can't use a conditional branch to reach this stub).
3651 static const Insn_template elf32_arm_stub_a8_veneer_b_cond
[] =
3653 Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
3654 Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
3655 Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
3659 // Stub used for b.w and bl.w instructions.
3661 static const Insn_template elf32_arm_stub_a8_veneer_b
[] =
3663 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
3666 static const Insn_template elf32_arm_stub_a8_veneer_bl
[] =
3668 Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
3671 // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
3672 // instruction (which switches to ARM mode) to point to this stub. Jump to
3673 // the real destination using an ARM-mode branch.
3674 static const Insn_template elf32_arm_stub_a8_veneer_blx
[] =
3676 Insn_template::arm_rel_insn(0xea000000, -8) // b dest
3679 // Fill in the stub template look-up table. Stub templates are constructed
3680 // per instance of Stub_factory for fast look-up without locking
3681 // in a thread-enabled environment.
3683 this->stub_templates_
[arm_stub_none
] =
3684 new Stub_template(arm_stub_none
, NULL
, 0);
3686 #define DEF_STUB(x) \
3690 = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
3691 Stub_type type = arm_stub_##x; \
3692 this->stub_templates_[type] = \
3693 new Stub_template(type, elf32_arm_stub_##x, array_size); \
3701 // Stub_table methods.
3703 // Removel all Cortex-A8 stub.
3705 template<bool big_endian
>
3707 Stub_table
<big_endian
>::remove_all_cortex_a8_stubs()
3709 for (Cortex_a8_stub_list::iterator p
= this->cortex_a8_stubs_
.begin();
3710 p
!= this->cortex_a8_stubs_
.end();
3713 this->cortex_a8_stubs_
.clear();
3716 // Relocate one stub. This is a helper for Stub_table::relocate_stubs().
3718 template<bool big_endian
>
3720 Stub_table
<big_endian
>::relocate_stub(
3722 const Relocate_info
<32, big_endian
>* relinfo
,
3723 Target_arm
<big_endian
>* arm_target
,
3724 Output_section
* output_section
,
3725 unsigned char* view
,
3726 Arm_address address
,
3727 section_size_type view_size
)
3729 const Stub_template
* stub_template
= stub
->stub_template();
3730 if (stub_template
->reloc_count() != 0)
3732 // Adjust view to cover the stub only.
3733 section_size_type offset
= stub
->offset();
3734 section_size_type stub_size
= stub_template
->size();
3735 gold_assert(offset
+ stub_size
<= view_size
);
3737 arm_target
->relocate_stub(stub
, relinfo
, output_section
, view
+ offset
,
3738 address
+ offset
, stub_size
);
3742 // Relocate all stubs in this stub table.
3744 template<bool big_endian
>
3746 Stub_table
<big_endian
>::relocate_stubs(
3747 const Relocate_info
<32, big_endian
>* relinfo
,
3748 Target_arm
<big_endian
>* arm_target
,
3749 Output_section
* output_section
,
3750 unsigned char* view
,
3751 Arm_address address
,
3752 section_size_type view_size
)
3754 // If we are passed a view bigger than the stub table's. we need to
3756 gold_assert(address
== this->address()
3758 == static_cast<section_size_type
>(this->data_size())));
3760 // Relocate all relocation stubs.
3761 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
3762 p
!= this->reloc_stubs_
.end();
3764 this->relocate_stub(p
->second
, relinfo
, arm_target
, output_section
, view
,
3765 address
, view_size
);
3767 // Relocate all Cortex-A8 stubs.
3768 for (Cortex_a8_stub_list::iterator p
= this->cortex_a8_stubs_
.begin();
3769 p
!= this->cortex_a8_stubs_
.end();
3771 this->relocate_stub(p
->second
, relinfo
, arm_target
, output_section
, view
,
3772 address
, view_size
);
3775 // Write out the stubs to file.
3777 template<bool big_endian
>
3779 Stub_table
<big_endian
>::do_write(Output_file
* of
)
3781 off_t offset
= this->offset();
3782 const section_size_type oview_size
=
3783 convert_to_section_size_type(this->data_size());
3784 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
3786 // Write relocation stubs.
3787 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
3788 p
!= this->reloc_stubs_
.end();
3791 Reloc_stub
* stub
= p
->second
;
3792 Arm_address address
= this->address() + stub
->offset();
3794 == align_address(address
,
3795 stub
->stub_template()->alignment()));
3796 stub
->write(oview
+ stub
->offset(), stub
->stub_template()->size(),
3800 // Write Cortex-A8 stubs.
3801 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
3802 p
!= this->cortex_a8_stubs_
.end();
3805 Cortex_a8_stub
* stub
= p
->second
;
3806 Arm_address address
= this->address() + stub
->offset();
3808 == align_address(address
,
3809 stub
->stub_template()->alignment()));
3810 stub
->write(oview
+ stub
->offset(), stub
->stub_template()->size(),
3814 of
->write_output_view(this->offset(), oview_size
, oview
);
3817 // Update the data size and address alignment of the stub table at the end
3818 // of a relaxation pass. Return true if either the data size or the
3819 // alignment changed in this relaxation pass.
3821 template<bool big_endian
>
3823 Stub_table
<big_endian
>::update_data_size_and_addralign()
3826 unsigned addralign
= 1;
3828 // Go over all stubs in table to compute data size and address alignment.
3830 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
3831 p
!= this->reloc_stubs_
.end();
3834 const Stub_template
* stub_template
= p
->second
->stub_template();
3835 addralign
= std::max(addralign
, stub_template
->alignment());
3836 size
= (align_address(size
, stub_template
->alignment())
3837 + stub_template
->size());
3840 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
3841 p
!= this->cortex_a8_stubs_
.end();
3844 const Stub_template
* stub_template
= p
->second
->stub_template();
3845 addralign
= std::max(addralign
, stub_template
->alignment());
3846 size
= (align_address(size
, stub_template
->alignment())
3847 + stub_template
->size());
3850 // Check if either data size or alignment changed in this pass.
3851 // Update prev_data_size_ and prev_addralign_. These will be used
3852 // as the current data size and address alignment for the next pass.
3853 bool changed
= size
!= this->prev_data_size_
;
3854 this->prev_data_size_
= size
;
3856 if (addralign
!= this->prev_addralign_
)
3858 this->prev_addralign_
= addralign
;
3863 // Finalize the stubs. This sets the offsets of the stubs within the stub
3864 // table. It also marks all input sections needing Cortex-A8 workaround.
3866 template<bool big_endian
>
3868 Stub_table
<big_endian
>::finalize_stubs()
3871 for (typename
Reloc_stub_map::const_iterator p
= this->reloc_stubs_
.begin();
3872 p
!= this->reloc_stubs_
.end();
3875 Reloc_stub
* stub
= p
->second
;
3876 const Stub_template
* stub_template
= stub
->stub_template();
3877 uint64_t stub_addralign
= stub_template
->alignment();
3878 off
= align_address(off
, stub_addralign
);
3879 stub
->set_offset(off
);
3880 off
+= stub_template
->size();
3883 for (Cortex_a8_stub_list::const_iterator p
= this->cortex_a8_stubs_
.begin();
3884 p
!= this->cortex_a8_stubs_
.end();
3887 Cortex_a8_stub
* stub
= p
->second
;
3888 const Stub_template
* stub_template
= stub
->stub_template();
3889 uint64_t stub_addralign
= stub_template
->alignment();
3890 off
= align_address(off
, stub_addralign
);
3891 stub
->set_offset(off
);
3892 off
+= stub_template
->size();
3894 // Mark input section so that we can determine later if a code section
3895 // needs the Cortex-A8 workaround quickly.
3896 Arm_relobj
<big_endian
>* arm_relobj
=
3897 Arm_relobj
<big_endian
>::as_arm_relobj(stub
->relobj());
3898 arm_relobj
->mark_section_for_cortex_a8_workaround(stub
->shndx());
3901 gold_assert(off
<= this->prev_data_size_
);
3904 // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
3905 // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
3906 // of the address range seen by the linker.
3908 template<bool big_endian
>
3910 Stub_table
<big_endian
>::apply_cortex_a8_workaround_to_address_range(
3911 Target_arm
<big_endian
>* arm_target
,
3912 unsigned char* view
,
3913 Arm_address view_address
,
3914 section_size_type view_size
)
3916 // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
3917 for (Cortex_a8_stub_list::const_iterator p
=
3918 this->cortex_a8_stubs_
.lower_bound(view_address
);
3919 ((p
!= this->cortex_a8_stubs_
.end())
3920 && (p
->first
< (view_address
+ view_size
)));
3923 // We do not store the THUMB bit in the LSB of either the branch address
3924 // or the stub offset. There is no need to strip the LSB.
3925 Arm_address branch_address
= p
->first
;
3926 const Cortex_a8_stub
* stub
= p
->second
;
3927 Arm_address stub_address
= this->address() + stub
->offset();
3929 // Offset of the branch instruction relative to this view.
3930 section_size_type offset
=
3931 convert_to_section_size_type(branch_address
- view_address
);
3932 gold_assert((offset
+ 4) <= view_size
);
3934 arm_target
->apply_cortex_a8_workaround(stub
, stub_address
,
3935 view
+ offset
, branch_address
);
3939 // Arm_input_section methods.
3941 // Initialize an Arm_input_section.
3943 template<bool big_endian
>
3945 Arm_input_section
<big_endian
>::init()
3947 Relobj
* relobj
= this->relobj();
3948 unsigned int shndx
= this->shndx();
3950 // Cache these to speed up size and alignment queries. It is too slow
3951 // to call section_addraglin and section_size every time.
3952 this->original_addralign_
= relobj
->section_addralign(shndx
);
3953 this->original_size_
= relobj
->section_size(shndx
);
3955 // We want to make this look like the original input section after
3956 // output sections are finalized.
3957 Output_section
* os
= relobj
->output_section(shndx
);
3958 off_t offset
= relobj
->output_section_offset(shndx
);
3959 gold_assert(os
!= NULL
&& !relobj
->is_output_section_offset_invalid(shndx
));
3960 this->set_address(os
->address() + offset
);
3961 this->set_file_offset(os
->offset() + offset
);
3963 this->set_current_data_size(this->original_size_
);
3964 this->finalize_data_size();
3967 template<bool big_endian
>
3969 Arm_input_section
<big_endian
>::do_write(Output_file
* of
)
3971 // We have to write out the original section content.
3972 section_size_type section_size
;
3973 const unsigned char* section_contents
=
3974 this->relobj()->section_contents(this->shndx(), §ion_size
, false);
3975 of
->write(this->offset(), section_contents
, section_size
);
3977 // If this owns a stub table and it is not empty, write it.
3978 if (this->is_stub_table_owner() && !this->stub_table_
->empty())
3979 this->stub_table_
->write(of
);
3982 // Finalize data size.
3984 template<bool big_endian
>
3986 Arm_input_section
<big_endian
>::set_final_data_size()
3988 // If this owns a stub table, finalize its data size as well.
3989 if (this->is_stub_table_owner())
3991 uint64_t address
= this->address();
3993 // The stub table comes after the original section contents.
3994 address
+= this->original_size_
;
3995 address
= align_address(address
, this->stub_table_
->addralign());
3996 off_t offset
= this->offset() + (address
- this->address());
3997 this->stub_table_
->set_address_and_file_offset(address
, offset
);
3998 address
+= this->stub_table_
->data_size();
3999 gold_assert(address
== this->address() + this->current_data_size());
4002 this->set_data_size(this->current_data_size());
4005 // Reset address and file offset.
4007 template<bool big_endian
>
4009 Arm_input_section
<big_endian
>::do_reset_address_and_file_offset()
4011 // Size of the original input section contents.
4012 off_t off
= convert_types
<off_t
, uint64_t>(this->original_size_
);
4014 // If this is a stub table owner, account for the stub table size.
4015 if (this->is_stub_table_owner())
4017 Stub_table
<big_endian
>* stub_table
= this->stub_table_
;
4019 // Reset the stub table's address and file offset. The
4020 // current data size for child will be updated after that.
4021 stub_table_
->reset_address_and_file_offset();
4022 off
= align_address(off
, stub_table_
->addralign());
4023 off
+= stub_table
->current_data_size();
4026 this->set_current_data_size(off
);
4029 // Arm_output_section methods.
4031 // Create a stub group for input sections from BEGIN to END. OWNER
4032 // points to the input section to be the owner a new stub table.
4034 template<bool big_endian
>
4036 Arm_output_section
<big_endian
>::create_stub_group(
4037 Input_section_list::const_iterator begin
,
4038 Input_section_list::const_iterator end
,
4039 Input_section_list::const_iterator owner
,
4040 Target_arm
<big_endian
>* target
,
4041 std::vector
<Output_relaxed_input_section
*>* new_relaxed_sections
)
4043 // Currently we convert ordinary input sections into relaxed sections only
4044 // at this point but we may want to support creating relaxed input section
4045 // very early. So we check here to see if owner is already a relaxed
4048 Arm_input_section
<big_endian
>* arm_input_section
;
4049 if (owner
->is_relaxed_input_section())
4052 Arm_input_section
<big_endian
>::as_arm_input_section(
4053 owner
->relaxed_input_section());
4057 gold_assert(owner
->is_input_section());
4058 // Create a new relaxed input section.
4060 target
->new_arm_input_section(owner
->relobj(), owner
->shndx());
4061 new_relaxed_sections
->push_back(arm_input_section
);
4064 // Create a stub table.
4065 Stub_table
<big_endian
>* stub_table
=
4066 target
->new_stub_table(arm_input_section
);
4068 arm_input_section
->set_stub_table(stub_table
);
4070 Input_section_list::const_iterator p
= begin
;
4071 Input_section_list::const_iterator prev_p
;
4073 // Look for input sections or relaxed input sections in [begin ... end].
4076 if (p
->is_input_section() || p
->is_relaxed_input_section())
4078 // The stub table information for input sections live
4079 // in their objects.
4080 Arm_relobj
<big_endian
>* arm_relobj
=
4081 Arm_relobj
<big_endian
>::as_arm_relobj(p
->relobj());
4082 arm_relobj
->set_stub_table(p
->shndx(), stub_table
);
4086 while (prev_p
!= end
);
4089 // Group input sections for stub generation. GROUP_SIZE is roughly the limit
4090 // of stub groups. We grow a stub group by adding input section until the
4091 // size is just below GROUP_SIZE. The last input section will be converted
4092 // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
4093 // input section after the stub table, effectively double the group size.
4095 // This is similar to the group_sections() function in elf32-arm.c but is
4096 // implemented differently.
4098 template<bool big_endian
>
4100 Arm_output_section
<big_endian
>::group_sections(
4101 section_size_type group_size
,
4102 bool stubs_always_after_branch
,
4103 Target_arm
<big_endian
>* target
)
4105 // We only care about sections containing code.
4106 if ((this->flags() & elfcpp::SHF_EXECINSTR
) == 0)
4109 // States for grouping.
4112 // No group is being built.
4114 // A group is being built but the stub table is not found yet.
4115 // We keep group a stub group until the size is just under GROUP_SIZE.
4116 // The last input section in the group will be used as the stub table.
4117 FINDING_STUB_SECTION
,
4118 // A group is being built and we have already found a stub table.
4119 // We enter this state to grow a stub group by adding input section
4120 // after the stub table. This effectively doubles the group size.
4124 // Any newly created relaxed sections are stored here.
4125 std::vector
<Output_relaxed_input_section
*> new_relaxed_sections
;
4127 State state
= NO_GROUP
;
4128 section_size_type off
= 0;
4129 section_size_type group_begin_offset
= 0;
4130 section_size_type group_end_offset
= 0;
4131 section_size_type stub_table_end_offset
= 0;
4132 Input_section_list::const_iterator group_begin
=
4133 this->input_sections().end();
4134 Input_section_list::const_iterator stub_table
=
4135 this->input_sections().end();
4136 Input_section_list::const_iterator group_end
= this->input_sections().end();
4137 for (Input_section_list::const_iterator p
= this->input_sections().begin();
4138 p
!= this->input_sections().end();
4141 section_size_type section_begin_offset
=
4142 align_address(off
, p
->addralign());
4143 section_size_type section_end_offset
=
4144 section_begin_offset
+ p
->data_size();
4146 // Check to see if we should group the previously seens sections.
4152 case FINDING_STUB_SECTION
:
4153 // Adding this section makes the group larger than GROUP_SIZE.
4154 if (section_end_offset
- group_begin_offset
>= group_size
)
4156 if (stubs_always_after_branch
)
4158 gold_assert(group_end
!= this->input_sections().end());
4159 this->create_stub_group(group_begin
, group_end
, group_end
,
4160 target
, &new_relaxed_sections
);
4165 // But wait, there's more! Input sections up to
4166 // stub_group_size bytes after the stub table can be
4167 // handled by it too.
4168 state
= HAS_STUB_SECTION
;
4169 stub_table
= group_end
;
4170 stub_table_end_offset
= group_end_offset
;
4175 case HAS_STUB_SECTION
:
4176 // Adding this section makes the post stub-section group larger
4178 if (section_end_offset
- stub_table_end_offset
>= group_size
)
4180 gold_assert(group_end
!= this->input_sections().end());
4181 this->create_stub_group(group_begin
, group_end
, stub_table
,
4182 target
, &new_relaxed_sections
);
4191 // If we see an input section and currently there is no group, start
4192 // a new one. Skip any empty sections.
4193 if ((p
->is_input_section() || p
->is_relaxed_input_section())
4194 && (p
->relobj()->section_size(p
->shndx()) != 0))
4196 if (state
== NO_GROUP
)
4198 state
= FINDING_STUB_SECTION
;
4200 group_begin_offset
= section_begin_offset
;
4203 // Keep track of the last input section seen.
4205 group_end_offset
= section_end_offset
;
4208 off
= section_end_offset
;
4211 // Create a stub group for any ungrouped sections.
4212 if (state
== FINDING_STUB_SECTION
|| state
== HAS_STUB_SECTION
)
4214 gold_assert(group_end
!= this->input_sections().end());
4215 this->create_stub_group(group_begin
, group_end
,
4216 (state
== FINDING_STUB_SECTION
4219 target
, &new_relaxed_sections
);
4222 // Convert input section into relaxed input section in a batch.
4223 if (!new_relaxed_sections
.empty())
4224 this->convert_input_sections_to_relaxed_sections(new_relaxed_sections
);
4226 // Update the section offsets
4227 for (size_t i
= 0; i
< new_relaxed_sections
.size(); ++i
)
4229 Arm_relobj
<big_endian
>* arm_relobj
=
4230 Arm_relobj
<big_endian
>::as_arm_relobj(
4231 new_relaxed_sections
[i
]->relobj());
4232 unsigned int shndx
= new_relaxed_sections
[i
]->shndx();
4233 // Tell Arm_relobj that this input section is converted.
4234 arm_relobj
->convert_input_section_to_relaxed_section(shndx
);
4238 // Arm_relobj methods.
4240 // Determine if we want to scan the SHNDX-th section for relocation stubs.
4241 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
4243 template<bool big_endian
>
4245 Arm_relobj
<big_endian
>::section_needs_reloc_stub_scanning(
4246 const elfcpp::Shdr
<32, big_endian
>& shdr
,
4247 const Relobj::Output_sections
& out_sections
,
4248 const Symbol_table
*symtab
)
4250 unsigned int sh_type
= shdr
.get_sh_type();
4251 if (sh_type
!= elfcpp::SHT_REL
&& sh_type
!= elfcpp::SHT_RELA
)
4254 // Ignore empty section.
4255 off_t sh_size
= shdr
.get_sh_size();
4259 // Ignore reloc section with bad info. This error will be
4260 // reported in the final link.
4261 unsigned int index
= this->adjust_shndx(shdr
.get_sh_info());
4262 if (index
>= this->shnum())
4265 // This relocation section is against a section which we
4266 // discarded or if the section is folded into another
4267 // section due to ICF.
4268 if (out_sections
[index
] == NULL
|| symtab
->is_section_folded(this, index
))
4271 // Ignore reloc section with unexpected symbol table. The
4272 // error will be reported in the final link.
4273 if (this->adjust_shndx(shdr
.get_sh_link()) != this->symtab_shndx())
4276 unsigned int reloc_size
;
4277 if (sh_type
== elfcpp::SHT_REL
)
4278 reloc_size
= elfcpp::Elf_sizes
<32>::rel_size
;
4280 reloc_size
= elfcpp::Elf_sizes
<32>::rela_size
;
4282 // Ignore reloc section with unexpected entsize or uneven size.
4283 // The error will be reported in the final link.
4284 if (reloc_size
!= shdr
.get_sh_entsize() || sh_size
% reloc_size
!= 0)
4290 // Determine if we want to scan the SHNDX-th section for non-relocation stubs.
4291 // This is a helper for Arm_relobj::scan_sections_for_stubs() below.
4293 template<bool big_endian
>
4295 Arm_relobj
<big_endian
>::section_needs_cortex_a8_stub_scanning(
4296 const elfcpp::Shdr
<32, big_endian
>& shdr
,
4299 const Symbol_table
* symtab
)
4301 // We only scan non-empty code sections.
4302 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) == 0
4303 || shdr
.get_sh_size() == 0)
4306 // Ignore discarded or ICF'ed sections.
4307 if (os
== NULL
|| symtab
->is_section_folded(this, shndx
))
4310 // Find output address of section.
4311 Arm_address address
= os
->output_address(this, shndx
, 0);
4313 // If the section does not cross any 4K-boundaries, it does not need to
4315 if ((address
& ~0xfffU
) == ((address
+ shdr
.get_sh_size() - 1) & ~0xfffU
))
4321 // Scan a section for Cortex-A8 workaround.
4323 template<bool big_endian
>
4325 Arm_relobj
<big_endian
>::scan_section_for_cortex_a8_erratum(
4326 const elfcpp::Shdr
<32, big_endian
>& shdr
,
4329 Target_arm
<big_endian
>* arm_target
)
4331 Arm_address output_address
= os
->output_address(this, shndx
, 0);
4333 // Get the section contents.
4334 section_size_type input_view_size
= 0;
4335 const unsigned char* input_view
=
4336 this->section_contents(shndx
, &input_view_size
, false);
4338 // We need to go through the mapping symbols to determine what to
4339 // scan. There are two reasons. First, we should look at THUMB code and
4340 // THUMB code only. Second, we only want to look at the 4K-page boundary
4341 // to speed up the scanning.
4343 // Look for the first mapping symbol in this section. It should be
4345 Mapping_symbol_position
section_start(shndx
, 0);
4346 typename
Mapping_symbols_info::const_iterator p
=
4347 this->mapping_symbols_info_
.lower_bound(section_start
);
4349 if (p
== this->mapping_symbols_info_
.end()
4350 || p
->first
!= section_start
)
4352 gold_warning(_("Cortex-A8 erratum scanning failed because there "
4353 "is no mapping symbols for section %u of %s"),
4354 shndx
, this->name().c_str());
4358 while (p
!= this->mapping_symbols_info_
.end()
4359 && p
->first
.first
== shndx
)
4361 typename
Mapping_symbols_info::const_iterator next
=
4362 this->mapping_symbols_info_
.upper_bound(p
->first
);
4364 // Only scan part of a section with THUMB code.
4365 if (p
->second
== 't')
4367 // Determine the end of this range.
4368 section_size_type span_start
=
4369 convert_to_section_size_type(p
->first
.second
);
4370 section_size_type span_end
;
4371 if (next
!= this->mapping_symbols_info_
.end()
4372 && next
->first
.first
== shndx
)
4373 span_end
= convert_to_section_size_type(next
->first
.second
);
4375 span_end
= convert_to_section_size_type(shdr
.get_sh_size());
4377 if (((span_start
+ output_address
) & ~0xfffUL
)
4378 != ((span_end
+ output_address
- 1) & ~0xfffUL
))
4380 arm_target
->scan_span_for_cortex_a8_erratum(this, shndx
,
4381 span_start
, span_end
,
4391 // Scan relocations for stub generation.
4393 template<bool big_endian
>
4395 Arm_relobj
<big_endian
>::scan_sections_for_stubs(
4396 Target_arm
<big_endian
>* arm_target
,
4397 const Symbol_table
* symtab
,
4398 const Layout
* layout
)
4400 unsigned int shnum
= this->shnum();
4401 const unsigned int shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
4403 // Read the section headers.
4404 const unsigned char* pshdrs
= this->get_view(this->elf_file()->shoff(),
4408 // To speed up processing, we set up hash tables for fast lookup of
4409 // input offsets to output addresses.
4410 this->initialize_input_to_output_maps();
4412 const Relobj::Output_sections
& out_sections(this->output_sections());
4414 Relocate_info
<32, big_endian
> relinfo
;
4415 relinfo
.symtab
= symtab
;
4416 relinfo
.layout
= layout
;
4417 relinfo
.object
= this;
4419 // Do relocation stubs scanning.
4420 const unsigned char* p
= pshdrs
+ shdr_size
;
4421 for (unsigned int i
= 1; i
< shnum
; ++i
, p
+= shdr_size
)
4423 const elfcpp::Shdr
<32, big_endian
> shdr(p
);
4424 if (this->section_needs_reloc_stub_scanning(shdr
, out_sections
, symtab
))
4426 unsigned int index
= this->adjust_shndx(shdr
.get_sh_info());
4427 Arm_address output_offset
= this->get_output_section_offset(index
);
4428 Arm_address output_address
;
4429 if(output_offset
!= invalid_address
)
4430 output_address
= out_sections
[index
]->address() + output_offset
;
4433 // Currently this only happens for a relaxed section.
4434 const Output_relaxed_input_section
* poris
=
4435 out_sections
[index
]->find_relaxed_input_section(this, index
);
4436 gold_assert(poris
!= NULL
);
4437 output_address
= poris
->address();
4440 // Get the relocations.
4441 const unsigned char* prelocs
= this->get_view(shdr
.get_sh_offset(),
4445 // Get the section contents. This does work for the case in which
4446 // we modify the contents of an input section. We need to pass the
4447 // output view under such circumstances.
4448 section_size_type input_view_size
= 0;
4449 const unsigned char* input_view
=
4450 this->section_contents(index
, &input_view_size
, false);
4452 relinfo
.reloc_shndx
= i
;
4453 relinfo
.data_shndx
= index
;
4454 unsigned int sh_type
= shdr
.get_sh_type();
4455 unsigned int reloc_size
;
4456 if (sh_type
== elfcpp::SHT_REL
)
4457 reloc_size
= elfcpp::Elf_sizes
<32>::rel_size
;
4459 reloc_size
= elfcpp::Elf_sizes
<32>::rela_size
;
4461 Output_section
* os
= out_sections
[index
];
4462 arm_target
->scan_section_for_stubs(&relinfo
, sh_type
, prelocs
,
4463 shdr
.get_sh_size() / reloc_size
,
4465 output_offset
== invalid_address
,
4466 input_view
, output_address
,
4471 // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
4472 // after its relocation section, if there is one, is processed for
4473 // relocation stubs. Merging this loop with the one above would have been
4474 // complicated since we would have had to make sure that relocation stub
4475 // scanning is done first.
4476 if (arm_target
->fix_cortex_a8())
4478 const unsigned char* p
= pshdrs
+ shdr_size
;
4479 for (unsigned int i
= 1; i
< shnum
; ++i
, p
+= shdr_size
)
4481 const elfcpp::Shdr
<32, big_endian
> shdr(p
);
4482 if (this->section_needs_cortex_a8_stub_scanning(shdr
, i
,
4485 this->scan_section_for_cortex_a8_erratum(shdr
, i
, out_sections
[i
],
4490 // After we've done the relocations, we release the hash tables,
4491 // since we no longer need them.
4492 this->free_input_to_output_maps();
4495 // Count the local symbols. The ARM backend needs to know if a symbol
4496 // is a THUMB function or not. For global symbols, it is easy because
4497 // the Symbol object keeps the ELF symbol type. For local symbol it is
4498 // harder because we cannot access this information. So we override the
4499 // do_count_local_symbol in parent and scan local symbols to mark
4500 // THUMB functions. This is not the most efficient way but I do not want to
4501 // slow down other ports by calling a per symbol targer hook inside
4502 // Sized_relobj<size, big_endian>::do_count_local_symbols.
4504 template<bool big_endian
>
4506 Arm_relobj
<big_endian
>::do_count_local_symbols(
4507 Stringpool_template
<char>* pool
,
4508 Stringpool_template
<char>* dynpool
)
4510 // We need to fix-up the values of any local symbols whose type are
4513 // Ask parent to count the local symbols.
4514 Sized_relobj
<32, big_endian
>::do_count_local_symbols(pool
, dynpool
);
4515 const unsigned int loccount
= this->local_symbol_count();
4519 // Intialize the thumb function bit-vector.
4520 std::vector
<bool> empty_vector(loccount
, false);
4521 this->local_symbol_is_thumb_function_
.swap(empty_vector
);
4523 // Read the symbol table section header.
4524 const unsigned int symtab_shndx
= this->symtab_shndx();
4525 elfcpp::Shdr
<32, big_endian
>
4526 symtabshdr(this, this->elf_file()->section_header(symtab_shndx
));
4527 gold_assert(symtabshdr
.get_sh_type() == elfcpp::SHT_SYMTAB
);
4529 // Read the local symbols.
4530 const int sym_size
=elfcpp::Elf_sizes
<32>::sym_size
;
4531 gold_assert(loccount
== symtabshdr
.get_sh_info());
4532 off_t locsize
= loccount
* sym_size
;
4533 const unsigned char* psyms
= this->get_view(symtabshdr
.get_sh_offset(),
4534 locsize
, true, true);
4536 // For mapping symbol processing, we need to read the symbol names.
4537 unsigned int strtab_shndx
= this->adjust_shndx(symtabshdr
.get_sh_link());
4538 if (strtab_shndx
>= this->shnum())
4540 this->error(_("invalid symbol table name index: %u"), strtab_shndx
);
4544 elfcpp::Shdr
<32, big_endian
>
4545 strtabshdr(this, this->elf_file()->section_header(strtab_shndx
));
4546 if (strtabshdr
.get_sh_type() != elfcpp::SHT_STRTAB
)
4548 this->error(_("symbol table name section has wrong type: %u"),
4549 static_cast<unsigned int>(strtabshdr
.get_sh_type()));
4552 const char* pnames
=
4553 reinterpret_cast<const char*>(this->get_view(strtabshdr
.get_sh_offset(),
4554 strtabshdr
.get_sh_size(),
4557 // Loop over the local symbols and mark any local symbols pointing
4558 // to THUMB functions.
4560 // Skip the first dummy symbol.
4562 typename Sized_relobj
<32, big_endian
>::Local_values
* plocal_values
=
4563 this->local_values();
4564 for (unsigned int i
= 1; i
< loccount
; ++i
, psyms
+= sym_size
)
4566 elfcpp::Sym
<32, big_endian
> sym(psyms
);
4567 elfcpp::STT st_type
= sym
.get_st_type();
4568 Symbol_value
<32>& lv((*plocal_values
)[i
]);
4569 Arm_address input_value
= lv
.input_value();
4571 // Check to see if this is a mapping symbol.
4572 const char* sym_name
= pnames
+ sym
.get_st_name();
4573 if (Target_arm
<big_endian
>::is_mapping_symbol_name(sym_name
))
4575 unsigned int input_shndx
= sym
.get_st_shndx();
4577 // Strip of LSB in case this is a THUMB symbol.
4578 Mapping_symbol_position
msp(input_shndx
, input_value
& ~1U);
4579 this->mapping_symbols_info_
[msp
] = sym_name
[1];
4582 if (st_type
== elfcpp::STT_ARM_TFUNC
4583 || (st_type
== elfcpp::STT_FUNC
&& ((input_value
& 1) != 0)))
4585 // This is a THUMB function. Mark this and canonicalize the
4586 // symbol value by setting LSB.
4587 this->local_symbol_is_thumb_function_
[i
] = true;
4588 if ((input_value
& 1) == 0)
4589 lv
.set_input_value(input_value
| 1);
4594 // Relocate sections.
4595 template<bool big_endian
>
4597 Arm_relobj
<big_endian
>::do_relocate_sections(
4598 const Symbol_table
* symtab
,
4599 const Layout
* layout
,
4600 const unsigned char* pshdrs
,
4601 typename Sized_relobj
<32, big_endian
>::Views
* pviews
)
4603 // Call parent to relocate sections.
4604 Sized_relobj
<32, big_endian
>::do_relocate_sections(symtab
, layout
, pshdrs
,
4607 // We do not generate stubs if doing a relocatable link.
4608 if (parameters
->options().relocatable())
4611 // Relocate stub tables.
4612 unsigned int shnum
= this->shnum();
4614 Target_arm
<big_endian
>* arm_target
=
4615 Target_arm
<big_endian
>::default_target();
4617 Relocate_info
<32, big_endian
> relinfo
;
4618 relinfo
.symtab
= symtab
;
4619 relinfo
.layout
= layout
;
4620 relinfo
.object
= this;
4622 for (unsigned int i
= 1; i
< shnum
; ++i
)
4624 Arm_input_section
<big_endian
>* arm_input_section
=
4625 arm_target
->find_arm_input_section(this, i
);
4627 if (arm_input_section
!= NULL
4628 && arm_input_section
->is_stub_table_owner()
4629 && !arm_input_section
->stub_table()->empty())
4631 // We cannot discard a section if it owns a stub table.
4632 Output_section
* os
= this->output_section(i
);
4633 gold_assert(os
!= NULL
);
4635 relinfo
.reloc_shndx
= elfcpp::SHN_UNDEF
;
4636 relinfo
.reloc_shdr
= NULL
;
4637 relinfo
.data_shndx
= i
;
4638 relinfo
.data_shdr
= pshdrs
+ i
* elfcpp::Elf_sizes
<32>::shdr_size
;
4640 gold_assert((*pviews
)[i
].view
!= NULL
);
4642 // We are passed the output section view. Adjust it to cover the
4644 Stub_table
<big_endian
>* stub_table
= arm_input_section
->stub_table();
4645 gold_assert((stub_table
->address() >= (*pviews
)[i
].address
)
4646 && ((stub_table
->address() + stub_table
->data_size())
4647 <= (*pviews
)[i
].address
+ (*pviews
)[i
].view_size
));
4649 off_t offset
= stub_table
->address() - (*pviews
)[i
].address
;
4650 unsigned char* view
= (*pviews
)[i
].view
+ offset
;
4651 Arm_address address
= stub_table
->address();
4652 section_size_type view_size
= stub_table
->data_size();
4654 stub_table
->relocate_stubs(&relinfo
, arm_target
, os
, view
, address
,
4658 // Apply Cortex A8 workaround if applicable.
4659 if (this->section_has_cortex_a8_workaround(i
))
4661 unsigned char* view
= (*pviews
)[i
].view
;
4662 Arm_address view_address
= (*pviews
)[i
].address
;
4663 section_size_type view_size
= (*pviews
)[i
].view_size
;
4664 Stub_table
<big_endian
>* stub_table
= this->stub_tables_
[i
];
4666 // Adjust view to cover section.
4667 Output_section
* os
= this->output_section(i
);
4668 gold_assert(os
!= NULL
);
4669 Arm_address section_address
= os
->output_address(this, i
, 0);
4670 uint64_t section_size
= this->section_size(i
);
4672 gold_assert(section_address
>= view_address
4673 && ((section_address
+ section_size
)
4674 <= (view_address
+ view_size
)));
4676 unsigned char* section_view
= view
+ (section_address
- view_address
);
4678 // Apply the Cortex-A8 workaround to the output address range
4679 // corresponding to this input section.
4680 stub_table
->apply_cortex_a8_workaround_to_address_range(
4689 // Helper functions for both Arm_relobj and Arm_dynobj to read ARM
4692 template<bool big_endian
>
4693 Attributes_section_data
*
4694 read_arm_attributes_section(
4696 Read_symbols_data
*sd
)
4698 // Read the attributes section if there is one.
4699 // We read from the end because gas seems to put it near the end of
4700 // the section headers.
4701 const size_t shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
4702 const unsigned char *ps
=
4703 sd
->section_headers
->data() + shdr_size
* (object
->shnum() - 1);
4704 for (unsigned int i
= object
->shnum(); i
> 0; --i
, ps
-= shdr_size
)
4706 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
4707 if (shdr
.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES
)
4709 section_offset_type section_offset
= shdr
.get_sh_offset();
4710 section_size_type section_size
=
4711 convert_to_section_size_type(shdr
.get_sh_size());
4712 File_view
* view
= object
->get_lasting_view(section_offset
,
4713 section_size
, true, false);
4714 return new Attributes_section_data(view
->data(), section_size
);
4720 // Read the symbol information.
4722 template<bool big_endian
>
4724 Arm_relobj
<big_endian
>::do_read_symbols(Read_symbols_data
* sd
)
4726 // Call parent class to read symbol information.
4727 Sized_relobj
<32, big_endian
>::do_read_symbols(sd
);
4729 // Read processor-specific flags in ELF file header.
4730 const unsigned char* pehdr
= this->get_view(elfcpp::file_header_offset
,
4731 elfcpp::Elf_sizes
<32>::ehdr_size
,
4733 elfcpp::Ehdr
<32, big_endian
> ehdr(pehdr
);
4734 this->processor_specific_flags_
= ehdr
.get_e_flags();
4735 this->attributes_section_data_
=
4736 read_arm_attributes_section
<big_endian
>(this, sd
);
4739 // Process relocations for garbage collection. The ARM target uses .ARM.exidx
4740 // sections for unwinding. These sections are referenced implicitly by
4741 // text sections linked in the section headers. If we ignore these implict
4742 // references, the .ARM.exidx sections and any .ARM.extab sections they use
4743 // will be garbage-collected incorrectly. Hence we override the same function
4744 // in the base class to handle these implicit references.
4746 template<bool big_endian
>
4748 Arm_relobj
<big_endian
>::do_gc_process_relocs(Symbol_table
* symtab
,
4750 Read_relocs_data
* rd
)
4752 // First, call base class method to process relocations in this object.
4753 Sized_relobj
<32, big_endian
>::do_gc_process_relocs(symtab
, layout
, rd
);
4755 unsigned int shnum
= this->shnum();
4756 const unsigned int shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
4757 const unsigned char* pshdrs
= this->get_view(this->elf_file()->shoff(),
4761 // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
4762 // to these from the linked text sections.
4763 const unsigned char* ps
= pshdrs
+ shdr_size
;
4764 for (unsigned int i
= 1; i
< shnum
; ++i
, ps
+= shdr_size
)
4766 elfcpp::Shdr
<32, big_endian
> shdr(ps
);
4767 if (shdr
.get_sh_type() == elfcpp::SHT_ARM_EXIDX
)
4769 // Found an .ARM.exidx section, add it to the set of reachable
4770 // sections from its linked text section.
4771 unsigned int text_shndx
= this->adjust_shndx(shdr
.get_sh_link());
4772 symtab
->gc()->add_reference(this, text_shndx
, this, i
);
4777 // Arm_dynobj methods.
4779 // Read the symbol information.
4781 template<bool big_endian
>
4783 Arm_dynobj
<big_endian
>::do_read_symbols(Read_symbols_data
* sd
)
4785 // Call parent class to read symbol information.
4786 Sized_dynobj
<32, big_endian
>::do_read_symbols(sd
);
4788 // Read processor-specific flags in ELF file header.
4789 const unsigned char* pehdr
= this->get_view(elfcpp::file_header_offset
,
4790 elfcpp::Elf_sizes
<32>::ehdr_size
,
4792 elfcpp::Ehdr
<32, big_endian
> ehdr(pehdr
);
4793 this->processor_specific_flags_
= ehdr
.get_e_flags();
4794 this->attributes_section_data_
=
4795 read_arm_attributes_section
<big_endian
>(this, sd
);
4798 // Stub_addend_reader methods.
4800 // Read the addend of a REL relocation of type R_TYPE at VIEW.
4802 template<bool big_endian
>
4803 elfcpp::Elf_types
<32>::Elf_Swxword
4804 Stub_addend_reader
<elfcpp::SHT_REL
, big_endian
>::operator()(
4805 unsigned int r_type
,
4806 const unsigned char* view
,
4807 const typename Reloc_types
<elfcpp::SHT_REL
, 32, big_endian
>::Reloc
&) const
4809 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
4813 case elfcpp::R_ARM_CALL
:
4814 case elfcpp::R_ARM_JUMP24
:
4815 case elfcpp::R_ARM_PLT32
:
4817 typedef typename
elfcpp::Swap
<32, big_endian
>::Valtype Valtype
;
4818 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
4819 Valtype val
= elfcpp::Swap
<32, big_endian
>::readval(wv
);
4820 return utils::sign_extend
<26>(val
<< 2);
4823 case elfcpp::R_ARM_THM_CALL
:
4824 case elfcpp::R_ARM_THM_JUMP24
:
4825 case elfcpp::R_ARM_THM_XPC22
:
4827 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
4828 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
4829 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
4830 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
4831 return RelocFuncs::thumb32_branch_offset(upper_insn
, lower_insn
);
4834 case elfcpp::R_ARM_THM_JUMP19
:
4836 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
4837 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
);
4838 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
4839 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
4840 return RelocFuncs::thumb32_cond_branch_offset(upper_insn
, lower_insn
);
4848 // A class to handle the PLT data.
4850 template<bool big_endian
>
4851 class Output_data_plt_arm
: public Output_section_data
4854 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, big_endian
>
4857 Output_data_plt_arm(Layout
*, Output_data_space
*);
4859 // Add an entry to the PLT.
4861 add_entry(Symbol
* gsym
);
4863 // Return the .rel.plt section data.
4864 const Reloc_section
*
4866 { return this->rel_
; }
4870 do_adjust_output_section(Output_section
* os
);
4872 // Write to a map file.
4874 do_print_to_mapfile(Mapfile
* mapfile
) const
4875 { mapfile
->print_output_data(this, _("** PLT")); }
4878 // Template for the first PLT entry.
4879 static const uint32_t first_plt_entry
[5];
4881 // Template for subsequent PLT entries.
4882 static const uint32_t plt_entry
[3];
4884 // Set the final size.
4886 set_final_data_size()
4888 this->set_data_size(sizeof(first_plt_entry
)
4889 + this->count_
* sizeof(plt_entry
));
4892 // Write out the PLT data.
4894 do_write(Output_file
*);
4896 // The reloc section.
4897 Reloc_section
* rel_
;
4898 // The .got.plt section.
4899 Output_data_space
* got_plt_
;
4900 // The number of PLT entries.
4901 unsigned int count_
;
4904 // Create the PLT section. The ordinary .got section is an argument,
4905 // since we need to refer to the start. We also create our own .got
4906 // section just for PLT entries.
4908 template<bool big_endian
>
4909 Output_data_plt_arm
<big_endian
>::Output_data_plt_arm(Layout
* layout
,
4910 Output_data_space
* got_plt
)
4911 : Output_section_data(4), got_plt_(got_plt
), count_(0)
4913 this->rel_
= new Reloc_section(false);
4914 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
4915 elfcpp::SHF_ALLOC
, this->rel_
, true, false,
4919 template<bool big_endian
>
4921 Output_data_plt_arm
<big_endian
>::do_adjust_output_section(Output_section
* os
)
4926 // Add an entry to the PLT.
4928 template<bool big_endian
>
4930 Output_data_plt_arm
<big_endian
>::add_entry(Symbol
* gsym
)
4932 gold_assert(!gsym
->has_plt_offset());
4934 // Note that when setting the PLT offset we skip the initial
4935 // reserved PLT entry.
4936 gsym
->set_plt_offset((this->count_
) * sizeof(plt_entry
)
4937 + sizeof(first_plt_entry
));
4941 section_offset_type got_offset
= this->got_plt_
->current_data_size();
4943 // Every PLT entry needs a GOT entry which points back to the PLT
4944 // entry (this will be changed by the dynamic linker, normally
4945 // lazily when the function is called).
4946 this->got_plt_
->set_current_data_size(got_offset
+ 4);
4948 // Every PLT entry needs a reloc.
4949 gsym
->set_needs_dynsym_entry();
4950 this->rel_
->add_global(gsym
, elfcpp::R_ARM_JUMP_SLOT
, this->got_plt_
,
4953 // Note that we don't need to save the symbol. The contents of the
4954 // PLT are independent of which symbols are used. The symbols only
4955 // appear in the relocations.
4959 // FIXME: This is not very flexible. Right now this has only been tested
4960 // on armv5te. If we are to support additional architecture features like
4961 // Thumb-2 or BE8, we need to make this more flexible like GNU ld.
4963 // The first entry in the PLT.
4964 template<bool big_endian
>
4965 const uint32_t Output_data_plt_arm
<big_endian
>::first_plt_entry
[5] =
4967 0xe52de004, // str lr, [sp, #-4]!
4968 0xe59fe004, // ldr lr, [pc, #4]
4969 0xe08fe00e, // add lr, pc, lr
4970 0xe5bef008, // ldr pc, [lr, #8]!
4971 0x00000000, // &GOT[0] - .
4974 // Subsequent entries in the PLT.
4976 template<bool big_endian
>
4977 const uint32_t Output_data_plt_arm
<big_endian
>::plt_entry
[3] =
4979 0xe28fc600, // add ip, pc, #0xNN00000
4980 0xe28cca00, // add ip, ip, #0xNN000
4981 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
4984 // Write out the PLT. This uses the hand-coded instructions above,
4985 // and adjusts them as needed. This is all specified by the arm ELF
4986 // Processor Supplement.
4988 template<bool big_endian
>
4990 Output_data_plt_arm
<big_endian
>::do_write(Output_file
* of
)
4992 const off_t offset
= this->offset();
4993 const section_size_type oview_size
=
4994 convert_to_section_size_type(this->data_size());
4995 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
4997 const off_t got_file_offset
= this->got_plt_
->offset();
4998 const section_size_type got_size
=
4999 convert_to_section_size_type(this->got_plt_
->data_size());
5000 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
5002 unsigned char* pov
= oview
;
5004 Arm_address plt_address
= this->address();
5005 Arm_address got_address
= this->got_plt_
->address();
5007 // Write first PLT entry. All but the last word are constants.
5008 const size_t num_first_plt_words
= (sizeof(first_plt_entry
)
5009 / sizeof(plt_entry
[0]));
5010 for (size_t i
= 0; i
< num_first_plt_words
- 1; i
++)
5011 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ i
* 4, first_plt_entry
[i
]);
5012 // Last word in first PLT entry is &GOT[0] - .
5013 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 16,
5014 got_address
- (plt_address
+ 16));
5015 pov
+= sizeof(first_plt_entry
);
5017 unsigned char* got_pov
= got_view
;
5019 memset(got_pov
, 0, 12);
5022 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
5023 unsigned int plt_offset
= sizeof(first_plt_entry
);
5024 unsigned int plt_rel_offset
= 0;
5025 unsigned int got_offset
= 12;
5026 const unsigned int count
= this->count_
;
5027 for (unsigned int i
= 0;
5030 pov
+= sizeof(plt_entry
),
5032 plt_offset
+= sizeof(plt_entry
),
5033 plt_rel_offset
+= rel_size
,
5036 // Set and adjust the PLT entry itself.
5037 int32_t offset
= ((got_address
+ got_offset
)
5038 - (plt_address
+ plt_offset
+ 8));
5040 gold_assert(offset
>= 0 && offset
< 0x0fffffff);
5041 uint32_t plt_insn0
= plt_entry
[0] | ((offset
>> 20) & 0xff);
5042 elfcpp::Swap
<32, big_endian
>::writeval(pov
, plt_insn0
);
5043 uint32_t plt_insn1
= plt_entry
[1] | ((offset
>> 12) & 0xff);
5044 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 4, plt_insn1
);
5045 uint32_t plt_insn2
= plt_entry
[2] | (offset
& 0xfff);
5046 elfcpp::Swap
<32, big_endian
>::writeval(pov
+ 8, plt_insn2
);
5048 // Set the entry in the GOT.
5049 elfcpp::Swap
<32, big_endian
>::writeval(got_pov
, plt_address
);
5052 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
5053 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
5055 of
->write_output_view(offset
, oview_size
, oview
);
5056 of
->write_output_view(got_file_offset
, got_size
, got_view
);
5059 // Create a PLT entry for a global symbol.
5061 template<bool big_endian
>
5063 Target_arm
<big_endian
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
5066 if (gsym
->has_plt_offset())
5069 if (this->plt_
== NULL
)
5071 // Create the GOT sections first.
5072 this->got_section(symtab
, layout
);
5074 this->plt_
= new Output_data_plt_arm
<big_endian
>(layout
, this->got_plt_
);
5075 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
5077 | elfcpp::SHF_EXECINSTR
),
5078 this->plt_
, false, false, false, false);
5080 this->plt_
->add_entry(gsym
);
5083 // Report an unsupported relocation against a local symbol.
5085 template<bool big_endian
>
5087 Target_arm
<big_endian
>::Scan::unsupported_reloc_local(
5088 Sized_relobj
<32, big_endian
>* object
,
5089 unsigned int r_type
)
5091 gold_error(_("%s: unsupported reloc %u against local symbol"),
5092 object
->name().c_str(), r_type
);
5095 // We are about to emit a dynamic relocation of type R_TYPE. If the
5096 // dynamic linker does not support it, issue an error. The GNU linker
5097 // only issues a non-PIC error for an allocated read-only section.
5098 // Here we know the section is allocated, but we don't know that it is
5099 // read-only. But we check for all the relocation types which the
5100 // glibc dynamic linker supports, so it seems appropriate to issue an
5101 // error even if the section is not read-only.
5103 template<bool big_endian
>
5105 Target_arm
<big_endian
>::Scan::check_non_pic(Relobj
* object
,
5106 unsigned int r_type
)
5110 // These are the relocation types supported by glibc for ARM.
5111 case elfcpp::R_ARM_RELATIVE
:
5112 case elfcpp::R_ARM_COPY
:
5113 case elfcpp::R_ARM_GLOB_DAT
:
5114 case elfcpp::R_ARM_JUMP_SLOT
:
5115 case elfcpp::R_ARM_ABS32
:
5116 case elfcpp::R_ARM_ABS32_NOI
:
5117 case elfcpp::R_ARM_PC24
:
5118 // FIXME: The following 3 types are not supported by Android's dynamic
5120 case elfcpp::R_ARM_TLS_DTPMOD32
:
5121 case elfcpp::R_ARM_TLS_DTPOFF32
:
5122 case elfcpp::R_ARM_TLS_TPOFF32
:
5126 // This prevents us from issuing more than one error per reloc
5127 // section. But we can still wind up issuing more than one
5128 // error per object file.
5129 if (this->issued_non_pic_error_
)
5131 object
->error(_("requires unsupported dynamic reloc; "
5132 "recompile with -fPIC"));
5133 this->issued_non_pic_error_
= true;
5136 case elfcpp::R_ARM_NONE
:
5141 // Scan a relocation for a local symbol.
5142 // FIXME: This only handles a subset of relocation types used by Android
5143 // on ARM v5te devices.
5145 template<bool big_endian
>
5147 Target_arm
<big_endian
>::Scan::local(Symbol_table
* symtab
,
5150 Sized_relobj
<32, big_endian
>* object
,
5151 unsigned int data_shndx
,
5152 Output_section
* output_section
,
5153 const elfcpp::Rel
<32, big_endian
>& reloc
,
5154 unsigned int r_type
,
5155 const elfcpp::Sym
<32, big_endian
>&)
5157 r_type
= get_real_reloc_type(r_type
);
5160 case elfcpp::R_ARM_NONE
:
5163 case elfcpp::R_ARM_ABS32
:
5164 case elfcpp::R_ARM_ABS32_NOI
:
5165 // If building a shared library (or a position-independent
5166 // executable), we need to create a dynamic relocation for
5167 // this location. The relocation applied at link time will
5168 // apply the link-time value, so we flag the location with
5169 // an R_ARM_RELATIVE relocation so the dynamic loader can
5170 // relocate it easily.
5171 if (parameters
->options().output_is_position_independent())
5173 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5174 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
5175 // If we are to add more other reloc types than R_ARM_ABS32,
5176 // we need to add check_non_pic(object, r_type) here.
5177 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_ARM_RELATIVE
,
5178 output_section
, data_shndx
,
5179 reloc
.get_r_offset());
5183 case elfcpp::R_ARM_REL32
:
5184 case elfcpp::R_ARM_THM_CALL
:
5185 case elfcpp::R_ARM_CALL
:
5186 case elfcpp::R_ARM_PREL31
:
5187 case elfcpp::R_ARM_JUMP24
:
5188 case elfcpp::R_ARM_THM_JUMP24
:
5189 case elfcpp::R_ARM_THM_JUMP19
:
5190 case elfcpp::R_ARM_PLT32
:
5191 case elfcpp::R_ARM_THM_ABS5
:
5192 case elfcpp::R_ARM_ABS8
:
5193 case elfcpp::R_ARM_ABS12
:
5194 case elfcpp::R_ARM_ABS16
:
5195 case elfcpp::R_ARM_BASE_ABS
:
5196 case elfcpp::R_ARM_MOVW_ABS_NC
:
5197 case elfcpp::R_ARM_MOVT_ABS
:
5198 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
5199 case elfcpp::R_ARM_THM_MOVT_ABS
:
5200 case elfcpp::R_ARM_MOVW_PREL_NC
:
5201 case elfcpp::R_ARM_MOVT_PREL
:
5202 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
5203 case elfcpp::R_ARM_THM_MOVT_PREL
:
5204 case elfcpp::R_ARM_THM_JUMP6
:
5205 case elfcpp::R_ARM_THM_JUMP8
:
5206 case elfcpp::R_ARM_THM_JUMP11
:
5209 case elfcpp::R_ARM_GOTOFF32
:
5210 // We need a GOT section:
5211 target
->got_section(symtab
, layout
);
5214 case elfcpp::R_ARM_BASE_PREL
:
5215 // FIXME: What about this?
5218 case elfcpp::R_ARM_GOT_BREL
:
5219 case elfcpp::R_ARM_GOT_PREL
:
5221 // The symbol requires a GOT entry.
5222 Output_data_got
<32, big_endian
>* got
=
5223 target
->got_section(symtab
, layout
);
5224 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
5225 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
5227 // If we are generating a shared object, we need to add a
5228 // dynamic RELATIVE relocation for this symbol's GOT entry.
5229 if (parameters
->options().output_is_position_independent())
5231 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5232 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
5233 rel_dyn
->add_local_relative(
5234 object
, r_sym
, elfcpp::R_ARM_RELATIVE
, got
,
5235 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
5241 case elfcpp::R_ARM_TARGET1
:
5242 // This should have been mapped to another type already.
5244 case elfcpp::R_ARM_COPY
:
5245 case elfcpp::R_ARM_GLOB_DAT
:
5246 case elfcpp::R_ARM_JUMP_SLOT
:
5247 case elfcpp::R_ARM_RELATIVE
:
5248 // These are relocations which should only be seen by the
5249 // dynamic linker, and should never be seen here.
5250 gold_error(_("%s: unexpected reloc %u in object file"),
5251 object
->name().c_str(), r_type
);
5255 unsupported_reloc_local(object
, r_type
);
5260 // Report an unsupported relocation against a global symbol.
5262 template<bool big_endian
>
5264 Target_arm
<big_endian
>::Scan::unsupported_reloc_global(
5265 Sized_relobj
<32, big_endian
>* object
,
5266 unsigned int r_type
,
5269 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
5270 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
5273 // Scan a relocation for a global symbol.
5274 // FIXME: This only handles a subset of relocation types used by Android
5275 // on ARM v5te devices.
5277 template<bool big_endian
>
5279 Target_arm
<big_endian
>::Scan::global(Symbol_table
* symtab
,
5282 Sized_relobj
<32, big_endian
>* object
,
5283 unsigned int data_shndx
,
5284 Output_section
* output_section
,
5285 const elfcpp::Rel
<32, big_endian
>& reloc
,
5286 unsigned int r_type
,
5289 r_type
= get_real_reloc_type(r_type
);
5292 case elfcpp::R_ARM_NONE
:
5295 case elfcpp::R_ARM_ABS32
:
5296 case elfcpp::R_ARM_ABS32_NOI
:
5298 // Make a dynamic relocation if necessary.
5299 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
5301 if (target
->may_need_copy_reloc(gsym
))
5303 target
->copy_reloc(symtab
, layout
, object
,
5304 data_shndx
, output_section
, gsym
, reloc
);
5306 else if (gsym
->can_use_relative_reloc(false))
5308 // If we are to add more other reloc types than R_ARM_ABS32,
5309 // we need to add check_non_pic(object, r_type) here.
5310 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5311 rel_dyn
->add_global_relative(gsym
, elfcpp::R_ARM_RELATIVE
,
5312 output_section
, object
,
5313 data_shndx
, reloc
.get_r_offset());
5317 // If we are to add more other reloc types than R_ARM_ABS32,
5318 // we need to add check_non_pic(object, r_type) here.
5319 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5320 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
5321 data_shndx
, reloc
.get_r_offset());
5327 case elfcpp::R_ARM_MOVW_ABS_NC
:
5328 case elfcpp::R_ARM_MOVT_ABS
:
5329 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
5330 case elfcpp::R_ARM_THM_MOVT_ABS
:
5331 case elfcpp::R_ARM_MOVW_PREL_NC
:
5332 case elfcpp::R_ARM_MOVT_PREL
:
5333 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
5334 case elfcpp::R_ARM_THM_MOVT_PREL
:
5335 case elfcpp::R_ARM_THM_JUMP6
:
5336 case elfcpp::R_ARM_THM_JUMP8
:
5337 case elfcpp::R_ARM_THM_JUMP11
:
5340 case elfcpp::R_ARM_THM_ABS5
:
5341 case elfcpp::R_ARM_ABS8
:
5342 case elfcpp::R_ARM_ABS12
:
5343 case elfcpp::R_ARM_ABS16
:
5344 case elfcpp::R_ARM_BASE_ABS
:
5346 // No dynamic relocs of this kinds.
5347 // Report the error in case of PIC.
5348 int flags
= Symbol::NON_PIC_REF
;
5349 if (gsym
->type() == elfcpp::STT_FUNC
5350 || gsym
->type() == elfcpp::STT_ARM_TFUNC
)
5351 flags
|= Symbol::FUNCTION_CALL
;
5352 if (gsym
->needs_dynamic_reloc(flags
))
5353 check_non_pic(object
, r_type
);
5357 case elfcpp::R_ARM_REL32
:
5358 case elfcpp::R_ARM_PREL31
:
5360 // Make a dynamic relocation if necessary.
5361 int flags
= Symbol::NON_PIC_REF
;
5362 if (gsym
->needs_dynamic_reloc(flags
))
5364 if (target
->may_need_copy_reloc(gsym
))
5366 target
->copy_reloc(symtab
, layout
, object
,
5367 data_shndx
, output_section
, gsym
, reloc
);
5371 check_non_pic(object
, r_type
);
5372 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5373 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
5374 data_shndx
, reloc
.get_r_offset());
5380 case elfcpp::R_ARM_JUMP24
:
5381 case elfcpp::R_ARM_THM_JUMP24
:
5382 case elfcpp::R_ARM_THM_JUMP19
:
5383 case elfcpp::R_ARM_CALL
:
5384 case elfcpp::R_ARM_THM_CALL
:
5386 if (Target_arm
<big_endian
>::Scan::symbol_needs_plt_entry(gsym
))
5387 target
->make_plt_entry(symtab
, layout
, gsym
);
5390 // Check to see if this is a function that would need a PLT
5391 // but does not get one because the function symbol is untyped.
5392 // This happens in assembly code missing a proper .type directive.
5393 if ((!gsym
->is_undefined() || parameters
->options().shared())
5394 && !parameters
->doing_static_link()
5395 && gsym
->type() == elfcpp::STT_NOTYPE
5396 && (gsym
->is_from_dynobj()
5397 || gsym
->is_undefined()
5398 || gsym
->is_preemptible()))
5399 gold_error(_("%s is not a function."),
5400 gsym
->demangled_name().c_str());
5404 case elfcpp::R_ARM_PLT32
:
5405 // If the symbol is fully resolved, this is just a relative
5406 // local reloc. Otherwise we need a PLT entry.
5407 if (gsym
->final_value_is_known())
5409 // If building a shared library, we can also skip the PLT entry
5410 // if the symbol is defined in the output file and is protected
5412 if (gsym
->is_defined()
5413 && !gsym
->is_from_dynobj()
5414 && !gsym
->is_preemptible())
5416 target
->make_plt_entry(symtab
, layout
, gsym
);
5419 case elfcpp::R_ARM_GOTOFF32
:
5420 // We need a GOT section.
5421 target
->got_section(symtab
, layout
);
5424 case elfcpp::R_ARM_BASE_PREL
:
5425 // FIXME: What about this?
5428 case elfcpp::R_ARM_GOT_BREL
:
5429 case elfcpp::R_ARM_GOT_PREL
:
5431 // The symbol requires a GOT entry.
5432 Output_data_got
<32, big_endian
>* got
=
5433 target
->got_section(symtab
, layout
);
5434 if (gsym
->final_value_is_known())
5435 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
5438 // If this symbol is not fully resolved, we need to add a
5439 // GOT entry with a dynamic relocation.
5440 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
5441 if (gsym
->is_from_dynobj()
5442 || gsym
->is_undefined()
5443 || gsym
->is_preemptible())
5444 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
5445 rel_dyn
, elfcpp::R_ARM_GLOB_DAT
);
5448 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
5449 rel_dyn
->add_global_relative(
5450 gsym
, elfcpp::R_ARM_RELATIVE
, got
,
5451 gsym
->got_offset(GOT_TYPE_STANDARD
));
5457 case elfcpp::R_ARM_TARGET1
:
5458 // This should have been mapped to another type already.
5460 case elfcpp::R_ARM_COPY
:
5461 case elfcpp::R_ARM_GLOB_DAT
:
5462 case elfcpp::R_ARM_JUMP_SLOT
:
5463 case elfcpp::R_ARM_RELATIVE
:
5464 // These are relocations which should only be seen by the
5465 // dynamic linker, and should never be seen here.
5466 gold_error(_("%s: unexpected reloc %u in object file"),
5467 object
->name().c_str(), r_type
);
5471 unsupported_reloc_global(object
, r_type
, gsym
);
5476 // Process relocations for gc.
5478 template<bool big_endian
>
5480 Target_arm
<big_endian
>::gc_process_relocs(Symbol_table
* symtab
,
5482 Sized_relobj
<32, big_endian
>* object
,
5483 unsigned int data_shndx
,
5485 const unsigned char* prelocs
,
5487 Output_section
* output_section
,
5488 bool needs_special_offset_handling
,
5489 size_t local_symbol_count
,
5490 const unsigned char* plocal_symbols
)
5492 typedef Target_arm
<big_endian
> Arm
;
5493 typedef typename Target_arm
<big_endian
>::Scan Scan
;
5495 gold::gc_process_relocs
<32, big_endian
, Arm
, elfcpp::SHT_REL
, Scan
>(
5504 needs_special_offset_handling
,
5509 // Scan relocations for a section.
5511 template<bool big_endian
>
5513 Target_arm
<big_endian
>::scan_relocs(Symbol_table
* symtab
,
5515 Sized_relobj
<32, big_endian
>* object
,
5516 unsigned int data_shndx
,
5517 unsigned int sh_type
,
5518 const unsigned char* prelocs
,
5520 Output_section
* output_section
,
5521 bool needs_special_offset_handling
,
5522 size_t local_symbol_count
,
5523 const unsigned char* plocal_symbols
)
5525 typedef typename Target_arm
<big_endian
>::Scan Scan
;
5526 if (sh_type
== elfcpp::SHT_RELA
)
5528 gold_error(_("%s: unsupported RELA reloc section"),
5529 object
->name().c_str());
5533 gold::scan_relocs
<32, big_endian
, Target_arm
, elfcpp::SHT_REL
, Scan
>(
5542 needs_special_offset_handling
,
5547 // Finalize the sections.
5549 template<bool big_endian
>
5551 Target_arm
<big_endian
>::do_finalize_sections(
5553 const Input_objects
* input_objects
,
5554 Symbol_table
* symtab
)
5556 // Merge processor-specific flags.
5557 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
5558 p
!= input_objects
->relobj_end();
5561 Arm_relobj
<big_endian
>* arm_relobj
=
5562 Arm_relobj
<big_endian
>::as_arm_relobj(*p
);
5563 this->merge_processor_specific_flags(
5565 arm_relobj
->processor_specific_flags());
5566 this->merge_object_attributes(arm_relobj
->name().c_str(),
5567 arm_relobj
->attributes_section_data());
5571 for (Input_objects::Dynobj_iterator p
= input_objects
->dynobj_begin();
5572 p
!= input_objects
->dynobj_end();
5575 Arm_dynobj
<big_endian
>* arm_dynobj
=
5576 Arm_dynobj
<big_endian
>::as_arm_dynobj(*p
);
5577 this->merge_processor_specific_flags(
5579 arm_dynobj
->processor_specific_flags());
5580 this->merge_object_attributes(arm_dynobj
->name().c_str(),
5581 arm_dynobj
->attributes_section_data());
5585 const Object_attribute
* cpu_arch_attr
=
5586 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch
);
5587 if (cpu_arch_attr
->int_value() > elfcpp::TAG_CPU_ARCH_V4
)
5588 this->set_may_use_blx(true);
5590 // Check if we need to use Cortex-A8 workaround.
5591 if (parameters
->options().user_set_fix_cortex_a8())
5592 this->fix_cortex_a8_
= parameters
->options().fix_cortex_a8();
5595 // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
5596 // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
5598 const Object_attribute
* cpu_arch_profile_attr
=
5599 this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile
);
5600 this->fix_cortex_a8_
=
5601 (cpu_arch_attr
->int_value() == elfcpp::TAG_CPU_ARCH_V7
5602 && (cpu_arch_profile_attr
->int_value() == 'A'
5603 || cpu_arch_profile_attr
->int_value() == 0));
5606 // Fill in some more dynamic tags.
5607 const Reloc_section
* rel_plt
= (this->plt_
== NULL
5609 : this->plt_
->rel_plt());
5610 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
5611 this->rel_dyn_
, true);
5613 // Emit any relocs we saved in an attempt to avoid generating COPY
5615 if (this->copy_relocs_
.any_saved_relocs())
5616 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
5618 // Handle the .ARM.exidx section.
5619 Output_section
* exidx_section
= layout
->find_output_section(".ARM.exidx");
5620 if (exidx_section
!= NULL
5621 && exidx_section
->type() == elfcpp::SHT_ARM_EXIDX
5622 && !parameters
->options().relocatable())
5624 // Create __exidx_start and __exdix_end symbols.
5625 symtab
->define_in_output_data("__exidx_start", NULL
,
5626 Symbol_table::PREDEFINED
,
5627 exidx_section
, 0, 0, elfcpp::STT_OBJECT
,
5628 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
, 0,
5630 symtab
->define_in_output_data("__exidx_end", NULL
,
5631 Symbol_table::PREDEFINED
,
5632 exidx_section
, 0, 0, elfcpp::STT_OBJECT
,
5633 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
, 0,
5636 // For the ARM target, we need to add a PT_ARM_EXIDX segment for
5637 // the .ARM.exidx section.
5638 if (!layout
->script_options()->saw_phdrs_clause())
5640 gold_assert(layout
->find_output_segment(elfcpp::PT_ARM_EXIDX
, 0, 0)
5642 Output_segment
* exidx_segment
=
5643 layout
->make_output_segment(elfcpp::PT_ARM_EXIDX
, elfcpp::PF_R
);
5644 exidx_segment
->add_output_section(exidx_section
, elfcpp::PF_R
,
5649 // Create an .ARM.attributes section if there is not one already.
5650 Output_attributes_section_data
* attributes_section
=
5651 new Output_attributes_section_data(*this->attributes_section_data_
);
5652 layout
->add_output_section_data(".ARM.attributes",
5653 elfcpp::SHT_ARM_ATTRIBUTES
, 0,
5654 attributes_section
, false, false, false,
5658 // Return whether a direct absolute static relocation needs to be applied.
5659 // In cases where Scan::local() or Scan::global() has created
5660 // a dynamic relocation other than R_ARM_RELATIVE, the addend
5661 // of the relocation is carried in the data, and we must not
5662 // apply the static relocation.
5664 template<bool big_endian
>
5666 Target_arm
<big_endian
>::Relocate::should_apply_static_reloc(
5667 const Sized_symbol
<32>* gsym
,
5670 Output_section
* output_section
)
5672 // If the output section is not allocated, then we didn't call
5673 // scan_relocs, we didn't create a dynamic reloc, and we must apply
5675 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
5678 // For local symbols, we will have created a non-RELATIVE dynamic
5679 // relocation only if (a) the output is position independent,
5680 // (b) the relocation is absolute (not pc- or segment-relative), and
5681 // (c) the relocation is not 32 bits wide.
5683 return !(parameters
->options().output_is_position_independent()
5684 && (ref_flags
& Symbol::ABSOLUTE_REF
)
5687 // For global symbols, we use the same helper routines used in the
5688 // scan pass. If we did not create a dynamic relocation, or if we
5689 // created a RELATIVE dynamic relocation, we should apply the static
5691 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
5692 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
5693 && gsym
->can_use_relative_reloc(ref_flags
5694 & Symbol::FUNCTION_CALL
);
5695 return !has_dyn
|| is_rel
;
5698 // Perform a relocation.
5700 template<bool big_endian
>
5702 Target_arm
<big_endian
>::Relocate::relocate(
5703 const Relocate_info
<32, big_endian
>* relinfo
,
5705 Output_section
*output_section
,
5707 const elfcpp::Rel
<32, big_endian
>& rel
,
5708 unsigned int r_type
,
5709 const Sized_symbol
<32>* gsym
,
5710 const Symbol_value
<32>* psymval
,
5711 unsigned char* view
,
5712 Arm_address address
,
5713 section_size_type
/* view_size */ )
5715 typedef Arm_relocate_functions
<big_endian
> Arm_relocate_functions
;
5717 r_type
= get_real_reloc_type(r_type
);
5719 const Arm_relobj
<big_endian
>* object
=
5720 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
5722 // If the final branch target of a relocation is THUMB instruction, this
5723 // is 1. Otherwise it is 0.
5724 Arm_address thumb_bit
= 0;
5725 Symbol_value
<32> symval
;
5726 bool is_weakly_undefined_without_plt
= false;
5727 if (relnum
!= Target_arm
<big_endian
>::fake_relnum_for_stubs
)
5731 // This is a global symbol. Determine if we use PLT and if the
5732 // final target is THUMB.
5733 if (gsym
->use_plt_offset(reloc_is_non_pic(r_type
)))
5735 // This uses a PLT, change the symbol value.
5736 symval
.set_output_value(target
->plt_section()->address()
5737 + gsym
->plt_offset());
5740 else if (gsym
->is_weak_undefined())
5742 // This is a weakly undefined symbol and we do not use PLT
5743 // for this relocation. A branch targeting this symbol will
5744 // be converted into an NOP.
5745 is_weakly_undefined_without_plt
= true;
5749 // Set thumb bit if symbol:
5750 // -Has type STT_ARM_TFUNC or
5751 // -Has type STT_FUNC, is defined and with LSB in value set.
5753 (((gsym
->type() == elfcpp::STT_ARM_TFUNC
)
5754 || (gsym
->type() == elfcpp::STT_FUNC
5755 && !gsym
->is_undefined()
5756 && ((psymval
->value(object
, 0) & 1) != 0)))
5763 // This is a local symbol. Determine if the final target is THUMB.
5764 // We saved this information when all the local symbols were read.
5765 elfcpp::Elf_types
<32>::Elf_WXword r_info
= rel
.get_r_info();
5766 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(r_info
);
5767 thumb_bit
= object
->local_symbol_is_thumb_function(r_sym
) ? 1 : 0;
5772 // This is a fake relocation synthesized for a stub. It does not have
5773 // a real symbol. We just look at the LSB of the symbol value to
5774 // determine if the target is THUMB or not.
5775 thumb_bit
= ((psymval
->value(object
, 0) & 1) != 0);
5778 // Strip LSB if this points to a THUMB target.
5780 && Target_arm
<big_endian
>::reloc_uses_thumb_bit(r_type
)
5781 && ((psymval
->value(object
, 0) & 1) != 0))
5783 Arm_address stripped_value
=
5784 psymval
->value(object
, 0) & ~static_cast<Arm_address
>(1);
5785 symval
.set_output_value(stripped_value
);
5789 // Get the GOT offset if needed.
5790 // The GOT pointer points to the end of the GOT section.
5791 // We need to subtract the size of the GOT section to get
5792 // the actual offset to use in the relocation.
5793 bool have_got_offset
= false;
5794 unsigned int got_offset
= 0;
5797 case elfcpp::R_ARM_GOT_BREL
:
5798 case elfcpp::R_ARM_GOT_PREL
:
5801 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
5802 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
5803 - target
->got_size());
5807 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
5808 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
5809 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
5810 - target
->got_size());
5812 have_got_offset
= true;
5819 // To look up relocation stubs, we need to pass the symbol table index of
5821 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
5823 typename
Arm_relocate_functions::Status reloc_status
=
5824 Arm_relocate_functions::STATUS_OKAY
;
5827 case elfcpp::R_ARM_NONE
:
5830 case elfcpp::R_ARM_ABS8
:
5831 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
5833 reloc_status
= Arm_relocate_functions::abs8(view
, object
, psymval
);
5836 case elfcpp::R_ARM_ABS12
:
5837 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
5839 reloc_status
= Arm_relocate_functions::abs12(view
, object
, psymval
);
5842 case elfcpp::R_ARM_ABS16
:
5843 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
5845 reloc_status
= Arm_relocate_functions::abs16(view
, object
, psymval
);
5848 case elfcpp::R_ARM_ABS32
:
5849 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5851 reloc_status
= Arm_relocate_functions::abs32(view
, object
, psymval
,
5855 case elfcpp::R_ARM_ABS32_NOI
:
5856 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5858 // No thumb bit for this relocation: (S + A)
5859 reloc_status
= Arm_relocate_functions::abs32(view
, object
, psymval
,
5863 case elfcpp::R_ARM_MOVW_ABS_NC
:
5864 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5866 reloc_status
= Arm_relocate_functions::movw_abs_nc(view
, object
,
5870 gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making"
5871 "a shared object; recompile with -fPIC"));
5874 case elfcpp::R_ARM_MOVT_ABS
:
5875 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5877 reloc_status
= Arm_relocate_functions::movt_abs(view
, object
, psymval
);
5879 gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making"
5880 "a shared object; recompile with -fPIC"));
5883 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
5884 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5886 reloc_status
= Arm_relocate_functions::thm_movw_abs_nc(view
, object
,
5890 gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when"
5891 "making a shared object; recompile with -fPIC"));
5894 case elfcpp::R_ARM_THM_MOVT_ABS
:
5895 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5897 reloc_status
= Arm_relocate_functions::thm_movt_abs(view
, object
,
5900 gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when"
5901 "making a shared object; recompile with -fPIC"));
5904 case elfcpp::R_ARM_MOVW_PREL_NC
:
5905 reloc_status
= Arm_relocate_functions::movw_prel_nc(view
, object
,
5910 case elfcpp::R_ARM_MOVT_PREL
:
5911 reloc_status
= Arm_relocate_functions::movt_prel(view
, object
,
5915 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
5916 reloc_status
= Arm_relocate_functions::thm_movw_prel_nc(view
, object
,
5921 case elfcpp::R_ARM_THM_MOVT_PREL
:
5922 reloc_status
= Arm_relocate_functions::thm_movt_prel(view
, object
,
5926 case elfcpp::R_ARM_REL32
:
5927 reloc_status
= Arm_relocate_functions::rel32(view
, object
, psymval
,
5928 address
, thumb_bit
);
5931 case elfcpp::R_ARM_THM_ABS5
:
5932 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
5934 reloc_status
= Arm_relocate_functions::thm_abs5(view
, object
, psymval
);
5937 case elfcpp::R_ARM_THM_CALL
:
5939 Arm_relocate_functions::thm_call(relinfo
, view
, gsym
, object
, r_sym
,
5940 psymval
, address
, thumb_bit
,
5941 is_weakly_undefined_without_plt
);
5944 case elfcpp::R_ARM_XPC25
:
5946 Arm_relocate_functions::xpc25(relinfo
, view
, gsym
, object
, r_sym
,
5947 psymval
, address
, thumb_bit
,
5948 is_weakly_undefined_without_plt
);
5951 case elfcpp::R_ARM_THM_XPC22
:
5953 Arm_relocate_functions::thm_xpc22(relinfo
, view
, gsym
, object
, r_sym
,
5954 psymval
, address
, thumb_bit
,
5955 is_weakly_undefined_without_plt
);
5958 case elfcpp::R_ARM_GOTOFF32
:
5960 Arm_address got_origin
;
5961 got_origin
= target
->got_plt_section()->address();
5962 reloc_status
= Arm_relocate_functions::rel32(view
, object
, psymval
,
5963 got_origin
, thumb_bit
);
5967 case elfcpp::R_ARM_BASE_PREL
:
5970 // Get the addressing origin of the output segment defining the
5971 // symbol gsym (AAELF 4.6.1.2 Relocation types)
5972 gold_assert(gsym
!= NULL
);
5973 if (gsym
->source() == Symbol::IN_OUTPUT_SEGMENT
)
5974 origin
= gsym
->output_segment()->vaddr();
5975 else if (gsym
->source () == Symbol::IN_OUTPUT_DATA
)
5976 origin
= gsym
->output_data()->address();
5979 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
5980 _("cannot find origin of R_ARM_BASE_PREL"));
5983 reloc_status
= Arm_relocate_functions::base_prel(view
, origin
, address
);
5987 case elfcpp::R_ARM_BASE_ABS
:
5989 if (!should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
5994 // Get the addressing origin of the output segment defining
5995 // the symbol gsym (AAELF 4.6.1.2 Relocation types).
5997 // R_ARM_BASE_ABS with the NULL symbol will give the
5998 // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
5999 // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
6000 origin
= target
->got_plt_section()->address();
6001 else if (gsym
->source() == Symbol::IN_OUTPUT_SEGMENT
)
6002 origin
= gsym
->output_segment()->vaddr();
6003 else if (gsym
->source () == Symbol::IN_OUTPUT_DATA
)
6004 origin
= gsym
->output_data()->address();
6007 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
6008 _("cannot find origin of R_ARM_BASE_ABS"));
6012 reloc_status
= Arm_relocate_functions::base_abs(view
, origin
);
6016 case elfcpp::R_ARM_GOT_BREL
:
6017 gold_assert(have_got_offset
);
6018 reloc_status
= Arm_relocate_functions::got_brel(view
, got_offset
);
6021 case elfcpp::R_ARM_GOT_PREL
:
6022 gold_assert(have_got_offset
);
6023 // Get the address origin for GOT PLT, which is allocated right
6024 // after the GOT section, to calculate an absolute address of
6025 // the symbol GOT entry (got_origin + got_offset).
6026 Arm_address got_origin
;
6027 got_origin
= target
->got_plt_section()->address();
6028 reloc_status
= Arm_relocate_functions::got_prel(view
,
6029 got_origin
+ got_offset
,
6033 case elfcpp::R_ARM_PLT32
:
6034 gold_assert(gsym
== NULL
6035 || gsym
->has_plt_offset()
6036 || gsym
->final_value_is_known()
6037 || (gsym
->is_defined()
6038 && !gsym
->is_from_dynobj()
6039 && !gsym
->is_preemptible()));
6041 Arm_relocate_functions::plt32(relinfo
, view
, gsym
, object
, r_sym
,
6042 psymval
, address
, thumb_bit
,
6043 is_weakly_undefined_without_plt
);
6046 case elfcpp::R_ARM_CALL
:
6048 Arm_relocate_functions::call(relinfo
, view
, gsym
, object
, r_sym
,
6049 psymval
, address
, thumb_bit
,
6050 is_weakly_undefined_without_plt
);
6053 case elfcpp::R_ARM_JUMP24
:
6055 Arm_relocate_functions::jump24(relinfo
, view
, gsym
, object
, r_sym
,
6056 psymval
, address
, thumb_bit
,
6057 is_weakly_undefined_without_plt
);
6060 case elfcpp::R_ARM_THM_JUMP24
:
6062 Arm_relocate_functions::thm_jump24(relinfo
, view
, gsym
, object
, r_sym
,
6063 psymval
, address
, thumb_bit
,
6064 is_weakly_undefined_without_plt
);
6067 case elfcpp::R_ARM_THM_JUMP19
:
6069 Arm_relocate_functions::thm_jump19(view
, object
, psymval
, address
,
6073 case elfcpp::R_ARM_THM_JUMP6
:
6075 Arm_relocate_functions::thm_jump6(view
, object
, psymval
, address
);
6078 case elfcpp::R_ARM_THM_JUMP8
:
6080 Arm_relocate_functions::thm_jump8(view
, object
, psymval
, address
);
6083 case elfcpp::R_ARM_THM_JUMP11
:
6085 Arm_relocate_functions::thm_jump11(view
, object
, psymval
, address
);
6088 case elfcpp::R_ARM_PREL31
:
6089 reloc_status
= Arm_relocate_functions::prel31(view
, object
, psymval
,
6090 address
, thumb_bit
);
6093 case elfcpp::R_ARM_TARGET1
:
6094 // This should have been mapped to another type already.
6096 case elfcpp::R_ARM_COPY
:
6097 case elfcpp::R_ARM_GLOB_DAT
:
6098 case elfcpp::R_ARM_JUMP_SLOT
:
6099 case elfcpp::R_ARM_RELATIVE
:
6100 // These are relocations which should only be seen by the
6101 // dynamic linker, and should never be seen here.
6102 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
6103 _("unexpected reloc %u in object file"),
6108 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
6109 _("unsupported reloc %u"),
6114 // Report any errors.
6115 switch (reloc_status
)
6117 case Arm_relocate_functions::STATUS_OKAY
:
6119 case Arm_relocate_functions::STATUS_OVERFLOW
:
6120 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
6121 _("relocation overflow in relocation %u"),
6124 case Arm_relocate_functions::STATUS_BAD_RELOC
:
6125 gold_error_at_location(
6129 _("unexpected opcode while processing relocation %u"),
6139 // Relocate section data.
6141 template<bool big_endian
>
6143 Target_arm
<big_endian
>::relocate_section(
6144 const Relocate_info
<32, big_endian
>* relinfo
,
6145 unsigned int sh_type
,
6146 const unsigned char* prelocs
,
6148 Output_section
* output_section
,
6149 bool needs_special_offset_handling
,
6150 unsigned char* view
,
6151 Arm_address address
,
6152 section_size_type view_size
,
6153 const Reloc_symbol_changes
* reloc_symbol_changes
)
6155 typedef typename Target_arm
<big_endian
>::Relocate Arm_relocate
;
6156 gold_assert(sh_type
== elfcpp::SHT_REL
);
6158 Arm_input_section
<big_endian
>* arm_input_section
=
6159 this->find_arm_input_section(relinfo
->object
, relinfo
->data_shndx
);
6161 // This is an ARM input section and the view covers the whole output
6163 if (arm_input_section
!= NULL
)
6165 gold_assert(needs_special_offset_handling
);
6166 Arm_address section_address
= arm_input_section
->address();
6167 section_size_type section_size
= arm_input_section
->data_size();
6169 gold_assert((arm_input_section
->address() >= address
)
6170 && ((arm_input_section
->address()
6171 + arm_input_section
->data_size())
6172 <= (address
+ view_size
)));
6174 off_t offset
= section_address
- address
;
6177 view_size
= section_size
;
6180 gold::relocate_section
<32, big_endian
, Target_arm
, elfcpp::SHT_REL
,
6187 needs_special_offset_handling
,
6191 reloc_symbol_changes
);
6194 // Return the size of a relocation while scanning during a relocatable
6197 template<bool big_endian
>
6199 Target_arm
<big_endian
>::Relocatable_size_for_reloc::get_size_for_reloc(
6200 unsigned int r_type
,
6203 r_type
= get_real_reloc_type(r_type
);
6206 case elfcpp::R_ARM_NONE
:
6209 case elfcpp::R_ARM_ABS8
:
6212 case elfcpp::R_ARM_ABS16
:
6213 case elfcpp::R_ARM_THM_ABS5
:
6214 case elfcpp::R_ARM_THM_JUMP6
:
6215 case elfcpp::R_ARM_THM_JUMP8
:
6216 case elfcpp::R_ARM_THM_JUMP11
:
6219 case elfcpp::R_ARM_ABS32
:
6220 case elfcpp::R_ARM_ABS32_NOI
:
6221 case elfcpp::R_ARM_ABS12
:
6222 case elfcpp::R_ARM_BASE_ABS
:
6223 case elfcpp::R_ARM_REL32
:
6224 case elfcpp::R_ARM_THM_CALL
:
6225 case elfcpp::R_ARM_GOTOFF32
:
6226 case elfcpp::R_ARM_BASE_PREL
:
6227 case elfcpp::R_ARM_GOT_BREL
:
6228 case elfcpp::R_ARM_GOT_PREL
:
6229 case elfcpp::R_ARM_PLT32
:
6230 case elfcpp::R_ARM_CALL
:
6231 case elfcpp::R_ARM_JUMP24
:
6232 case elfcpp::R_ARM_PREL31
:
6233 case elfcpp::R_ARM_MOVW_ABS_NC
:
6234 case elfcpp::R_ARM_MOVT_ABS
:
6235 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
6236 case elfcpp::R_ARM_THM_MOVT_ABS
:
6237 case elfcpp::R_ARM_MOVW_PREL_NC
:
6238 case elfcpp::R_ARM_MOVT_PREL
:
6239 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
6240 case elfcpp::R_ARM_THM_MOVT_PREL
:
6243 case elfcpp::R_ARM_TARGET1
:
6244 // This should have been mapped to another type already.
6246 case elfcpp::R_ARM_COPY
:
6247 case elfcpp::R_ARM_GLOB_DAT
:
6248 case elfcpp::R_ARM_JUMP_SLOT
:
6249 case elfcpp::R_ARM_RELATIVE
:
6250 // These are relocations which should only be seen by the
6251 // dynamic linker, and should never be seen here.
6252 gold_error(_("%s: unexpected reloc %u in object file"),
6253 object
->name().c_str(), r_type
);
6257 object
->error(_("unsupported reloc %u in object file"), r_type
);
6262 // Scan the relocs during a relocatable link.
6264 template<bool big_endian
>
6266 Target_arm
<big_endian
>::scan_relocatable_relocs(
6267 Symbol_table
* symtab
,
6269 Sized_relobj
<32, big_endian
>* object
,
6270 unsigned int data_shndx
,
6271 unsigned int sh_type
,
6272 const unsigned char* prelocs
,
6274 Output_section
* output_section
,
6275 bool needs_special_offset_handling
,
6276 size_t local_symbol_count
,
6277 const unsigned char* plocal_symbols
,
6278 Relocatable_relocs
* rr
)
6280 gold_assert(sh_type
== elfcpp::SHT_REL
);
6282 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
6283 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
6285 gold::scan_relocatable_relocs
<32, big_endian
, elfcpp::SHT_REL
,
6286 Scan_relocatable_relocs
>(
6294 needs_special_offset_handling
,
6300 // Relocate a section during a relocatable link.
6302 template<bool big_endian
>
6304 Target_arm
<big_endian
>::relocate_for_relocatable(
6305 const Relocate_info
<32, big_endian
>* relinfo
,
6306 unsigned int sh_type
,
6307 const unsigned char* prelocs
,
6309 Output_section
* output_section
,
6310 off_t offset_in_output_section
,
6311 const Relocatable_relocs
* rr
,
6312 unsigned char* view
,
6313 Arm_address view_address
,
6314 section_size_type view_size
,
6315 unsigned char* reloc_view
,
6316 section_size_type reloc_view_size
)
6318 gold_assert(sh_type
== elfcpp::SHT_REL
);
6320 gold::relocate_for_relocatable
<32, big_endian
, elfcpp::SHT_REL
>(
6325 offset_in_output_section
,
6334 // Return the value to use for a dynamic symbol which requires special
6335 // treatment. This is how we support equality comparisons of function
6336 // pointers across shared library boundaries, as described in the
6337 // processor specific ABI supplement.
6339 template<bool big_endian
>
6341 Target_arm
<big_endian
>::do_dynsym_value(const Symbol
* gsym
) const
6343 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
6344 return this->plt_section()->address() + gsym
->plt_offset();
6347 // Map platform-specific relocs to real relocs
6349 template<bool big_endian
>
6351 Target_arm
<big_endian
>::get_real_reloc_type (unsigned int r_type
)
6355 case elfcpp::R_ARM_TARGET1
:
6356 // This is either R_ARM_ABS32 or R_ARM_REL32;
6357 return elfcpp::R_ARM_ABS32
;
6359 case elfcpp::R_ARM_TARGET2
:
6360 // This can be any reloc type but ususally is R_ARM_GOT_PREL
6361 return elfcpp::R_ARM_GOT_PREL
;
6368 // Whether if two EABI versions V1 and V2 are compatible.
6370 template<bool big_endian
>
6372 Target_arm
<big_endian
>::are_eabi_versions_compatible(
6373 elfcpp::Elf_Word v1
,
6374 elfcpp::Elf_Word v2
)
6376 // v4 and v5 are the same spec before and after it was released,
6377 // so allow mixing them.
6378 if ((v1
== elfcpp::EF_ARM_EABI_VER4
&& v2
== elfcpp::EF_ARM_EABI_VER5
)
6379 || (v1
== elfcpp::EF_ARM_EABI_VER5
&& v2
== elfcpp::EF_ARM_EABI_VER4
))
6385 // Combine FLAGS from an input object called NAME and the processor-specific
6386 // flags in the ELF header of the output. Much of this is adapted from the
6387 // processor-specific flags merging code in elf32_arm_merge_private_bfd_data
6388 // in bfd/elf32-arm.c.
6390 template<bool big_endian
>
6392 Target_arm
<big_endian
>::merge_processor_specific_flags(
6393 const std::string
& name
,
6394 elfcpp::Elf_Word flags
)
6396 if (this->are_processor_specific_flags_set())
6398 elfcpp::Elf_Word out_flags
= this->processor_specific_flags();
6400 // Nothing to merge if flags equal to those in output.
6401 if (flags
== out_flags
)
6404 // Complain about various flag mismatches.
6405 elfcpp::Elf_Word version1
= elfcpp::arm_eabi_version(flags
);
6406 elfcpp::Elf_Word version2
= elfcpp::arm_eabi_version(out_flags
);
6407 if (!this->are_eabi_versions_compatible(version1
, version2
))
6408 gold_error(_("Source object %s has EABI version %d but output has "
6409 "EABI version %d."),
6411 (flags
& elfcpp::EF_ARM_EABIMASK
) >> 24,
6412 (out_flags
& elfcpp::EF_ARM_EABIMASK
) >> 24);
6416 // If the input is the default architecture and had the default
6417 // flags then do not bother setting the flags for the output
6418 // architecture, instead allow future merges to do this. If no
6419 // future merges ever set these flags then they will retain their
6420 // uninitialised values, which surprise surprise, correspond
6421 // to the default values.
6425 // This is the first time, just copy the flags.
6426 // We only copy the EABI version for now.
6427 this->set_processor_specific_flags(flags
& elfcpp::EF_ARM_EABIMASK
);
6431 // Adjust ELF file header.
6432 template<bool big_endian
>
6434 Target_arm
<big_endian
>::do_adjust_elf_header(
6435 unsigned char* view
,
6438 gold_assert(len
== elfcpp::Elf_sizes
<32>::ehdr_size
);
6440 elfcpp::Ehdr
<32, big_endian
> ehdr(view
);
6441 unsigned char e_ident
[elfcpp::EI_NIDENT
];
6442 memcpy(e_ident
, ehdr
.get_e_ident(), elfcpp::EI_NIDENT
);
6444 if (elfcpp::arm_eabi_version(this->processor_specific_flags())
6445 == elfcpp::EF_ARM_EABI_UNKNOWN
)
6446 e_ident
[elfcpp::EI_OSABI
] = elfcpp::ELFOSABI_ARM
;
6448 e_ident
[elfcpp::EI_OSABI
] = 0;
6449 e_ident
[elfcpp::EI_ABIVERSION
] = 0;
6451 // FIXME: Do EF_ARM_BE8 adjustment.
6453 elfcpp::Ehdr_write
<32, big_endian
> oehdr(view
);
6454 oehdr
.put_e_ident(e_ident
);
6457 // do_make_elf_object to override the same function in the base class.
6458 // We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
6459 // to store ARM specific information. Hence we need to have our own
6460 // ELF object creation.
6462 template<bool big_endian
>
6464 Target_arm
<big_endian
>::do_make_elf_object(
6465 const std::string
& name
,
6466 Input_file
* input_file
,
6467 off_t offset
, const elfcpp::Ehdr
<32, big_endian
>& ehdr
)
6469 int et
= ehdr
.get_e_type();
6470 if (et
== elfcpp::ET_REL
)
6472 Arm_relobj
<big_endian
>* obj
=
6473 new Arm_relobj
<big_endian
>(name
, input_file
, offset
, ehdr
);
6477 else if (et
== elfcpp::ET_DYN
)
6479 Sized_dynobj
<32, big_endian
>* obj
=
6480 new Arm_dynobj
<big_endian
>(name
, input_file
, offset
, ehdr
);
6486 gold_error(_("%s: unsupported ELF file type %d"),
6492 // Read the architecture from the Tag_also_compatible_with attribute, if any.
6493 // Returns -1 if no architecture could be read.
6494 // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
6496 template<bool big_endian
>
6498 Target_arm
<big_endian
>::get_secondary_compatible_arch(
6499 const Attributes_section_data
* pasd
)
6501 const Object_attribute
*known_attributes
=
6502 pasd
->known_attributes(Object_attribute::OBJ_ATTR_PROC
);
6504 // Note: the tag and its argument below are uleb128 values, though
6505 // currently-defined values fit in one byte for each.
6506 const std::string
& sv
=
6507 known_attributes
[elfcpp::Tag_also_compatible_with
].string_value();
6509 && sv
.data()[0] == elfcpp::Tag_CPU_arch
6510 && (sv
.data()[1] & 128) != 128)
6511 return sv
.data()[1];
6513 // This tag is "safely ignorable", so don't complain if it looks funny.
6517 // Set, or unset, the architecture of the Tag_also_compatible_with attribute.
6518 // The tag is removed if ARCH is -1.
6519 // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
6521 template<bool big_endian
>
6523 Target_arm
<big_endian
>::set_secondary_compatible_arch(
6524 Attributes_section_data
* pasd
,
6527 Object_attribute
*known_attributes
=
6528 pasd
->known_attributes(Object_attribute::OBJ_ATTR_PROC
);
6532 known_attributes
[elfcpp::Tag_also_compatible_with
].set_string_value("");
6536 // Note: the tag and its argument below are uleb128 values, though
6537 // currently-defined values fit in one byte for each.
6539 sv
[0] = elfcpp::Tag_CPU_arch
;
6540 gold_assert(arch
!= 0);
6544 known_attributes
[elfcpp::Tag_also_compatible_with
].set_string_value(sv
);
6547 // Combine two values for Tag_CPU_arch, taking secondary compatibility tags
6549 // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
6551 template<bool big_endian
>
6553 Target_arm
<big_endian
>::tag_cpu_arch_combine(
6556 int* secondary_compat_out
,
6558 int secondary_compat
)
6560 #define T(X) elfcpp::TAG_CPU_ARCH_##X
6561 static const int v6t2
[] =
6573 static const int v6k
[] =
6586 static const int v7
[] =
6600 static const int v6_m
[] =
6615 static const int v6s_m
[] =
6631 static const int v7e_m
[] =
6648 static const int v4t_plus_v6_m
[] =
6664 T(V4T_PLUS_V6_M
) // V4T plus V6_M.
6666 static const int *comb
[] =
6674 // Pseudo-architecture.
6678 // Check we've not got a higher architecture than we know about.
6680 if (oldtag
>= elfcpp::MAX_TAG_CPU_ARCH
|| newtag
>= elfcpp::MAX_TAG_CPU_ARCH
)
6682 gold_error(_("%s: unknown CPU architecture"), name
);
6686 // Override old tag if we have a Tag_also_compatible_with on the output.
6688 if ((oldtag
== T(V6_M
) && *secondary_compat_out
== T(V4T
))
6689 || (oldtag
== T(V4T
) && *secondary_compat_out
== T(V6_M
)))
6690 oldtag
= T(V4T_PLUS_V6_M
);
6692 // And override the new tag if we have a Tag_also_compatible_with on the
6695 if ((newtag
== T(V6_M
) && secondary_compat
== T(V4T
))
6696 || (newtag
== T(V4T
) && secondary_compat
== T(V6_M
)))
6697 newtag
= T(V4T_PLUS_V6_M
);
6699 // Architectures before V6KZ add features monotonically.
6700 int tagh
= std::max(oldtag
, newtag
);
6701 if (tagh
<= elfcpp::TAG_CPU_ARCH_V6KZ
)
6704 int tagl
= std::min(oldtag
, newtag
);
6705 int result
= comb
[tagh
- T(V6T2
)][tagl
];
6707 // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
6708 // as the canonical version.
6709 if (result
== T(V4T_PLUS_V6_M
))
6712 *secondary_compat_out
= T(V6_M
);
6715 *secondary_compat_out
= -1;
6719 gold_error(_("%s: conflicting CPU architectures %d/%d"),
6720 name
, oldtag
, newtag
);
6728 // Helper to print AEABI enum tag value.
6730 template<bool big_endian
>
6732 Target_arm
<big_endian
>::aeabi_enum_name(unsigned int value
)
6734 static const char *aeabi_enum_names
[] =
6735 { "", "variable-size", "32-bit", "" };
6736 const size_t aeabi_enum_names_size
=
6737 sizeof(aeabi_enum_names
) / sizeof(aeabi_enum_names
[0]);
6739 if (value
< aeabi_enum_names_size
)
6740 return std::string(aeabi_enum_names
[value
]);
6744 sprintf(buffer
, "<unknown value %u>", value
);
6745 return std::string(buffer
);
6749 // Return the string value to store in TAG_CPU_name.
6751 template<bool big_endian
>
6753 Target_arm
<big_endian
>::tag_cpu_name_value(unsigned int value
)
6755 static const char *name_table
[] = {
6756 // These aren't real CPU names, but we can't guess
6757 // that from the architecture version alone.
6773 const size_t name_table_size
= sizeof(name_table
) / sizeof(name_table
[0]);
6775 if (value
< name_table_size
)
6776 return std::string(name_table
[value
]);
6780 sprintf(buffer
, "<unknown CPU value %u>", value
);
6781 return std::string(buffer
);
6785 // Merge object attributes from input file called NAME with those of the
6786 // output. The input object attributes are in the object pointed by PASD.
6788 template<bool big_endian
>
6790 Target_arm
<big_endian
>::merge_object_attributes(
6792 const Attributes_section_data
* pasd
)
6794 // Return if there is no attributes section data.
6798 // If output has no object attributes, just copy.
6799 if (this->attributes_section_data_
== NULL
)
6801 this->attributes_section_data_
= new Attributes_section_data(*pasd
);
6805 const int vendor
= Object_attribute::OBJ_ATTR_PROC
;
6806 const Object_attribute
* in_attr
= pasd
->known_attributes(vendor
);
6807 Object_attribute
* out_attr
=
6808 this->attributes_section_data_
->known_attributes(vendor
);
6810 // This needs to happen before Tag_ABI_FP_number_model is merged. */
6811 if (in_attr
[elfcpp::Tag_ABI_VFP_args
].int_value()
6812 != out_attr
[elfcpp::Tag_ABI_VFP_args
].int_value())
6814 // Ignore mismatches if the object doesn't use floating point. */
6815 if (out_attr
[elfcpp::Tag_ABI_FP_number_model
].int_value() == 0)
6816 out_attr
[elfcpp::Tag_ABI_VFP_args
].set_int_value(
6817 in_attr
[elfcpp::Tag_ABI_VFP_args
].int_value());
6818 else if (in_attr
[elfcpp::Tag_ABI_FP_number_model
].int_value() != 0)
6819 gold_error(_("%s uses VFP register arguments, output does not"),
6823 for (int i
= 4; i
< Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES
; ++i
)
6825 // Merge this attribute with existing attributes.
6828 case elfcpp::Tag_CPU_raw_name
:
6829 case elfcpp::Tag_CPU_name
:
6830 // These are merged after Tag_CPU_arch.
6833 case elfcpp::Tag_ABI_optimization_goals
:
6834 case elfcpp::Tag_ABI_FP_optimization_goals
:
6835 // Use the first value seen.
6838 case elfcpp::Tag_CPU_arch
:
6840 unsigned int saved_out_attr
= out_attr
->int_value();
6841 // Merge Tag_CPU_arch and Tag_also_compatible_with.
6842 int secondary_compat
=
6843 this->get_secondary_compatible_arch(pasd
);
6844 int secondary_compat_out
=
6845 this->get_secondary_compatible_arch(
6846 this->attributes_section_data_
);
6847 out_attr
[i
].set_int_value(
6848 tag_cpu_arch_combine(name
, out_attr
[i
].int_value(),
6849 &secondary_compat_out
,
6850 in_attr
[i
].int_value(),
6852 this->set_secondary_compatible_arch(this->attributes_section_data_
,
6853 secondary_compat_out
);
6855 // Merge Tag_CPU_name and Tag_CPU_raw_name.
6856 if (out_attr
[i
].int_value() == saved_out_attr
)
6857 ; // Leave the names alone.
6858 else if (out_attr
[i
].int_value() == in_attr
[i
].int_value())
6860 // The output architecture has been changed to match the
6861 // input architecture. Use the input names.
6862 out_attr
[elfcpp::Tag_CPU_name
].set_string_value(
6863 in_attr
[elfcpp::Tag_CPU_name
].string_value());
6864 out_attr
[elfcpp::Tag_CPU_raw_name
].set_string_value(
6865 in_attr
[elfcpp::Tag_CPU_raw_name
].string_value());
6869 out_attr
[elfcpp::Tag_CPU_name
].set_string_value("");
6870 out_attr
[elfcpp::Tag_CPU_raw_name
].set_string_value("");
6873 // If we still don't have a value for Tag_CPU_name,
6874 // make one up now. Tag_CPU_raw_name remains blank.
6875 if (out_attr
[elfcpp::Tag_CPU_name
].string_value() == "")
6877 const std::string cpu_name
=
6878 this->tag_cpu_name_value(out_attr
[i
].int_value());
6879 // FIXME: If we see an unknown CPU, this will be set
6880 // to "<unknown CPU n>", where n is the attribute value.
6881 // This is different from BFD, which leaves the name alone.
6882 out_attr
[elfcpp::Tag_CPU_name
].set_string_value(cpu_name
);
6887 case elfcpp::Tag_ARM_ISA_use
:
6888 case elfcpp::Tag_THUMB_ISA_use
:
6889 case elfcpp::Tag_WMMX_arch
:
6890 case elfcpp::Tag_Advanced_SIMD_arch
:
6891 // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
6892 case elfcpp::Tag_ABI_FP_rounding
:
6893 case elfcpp::Tag_ABI_FP_exceptions
:
6894 case elfcpp::Tag_ABI_FP_user_exceptions
:
6895 case elfcpp::Tag_ABI_FP_number_model
:
6896 case elfcpp::Tag_VFP_HP_extension
:
6897 case elfcpp::Tag_CPU_unaligned_access
:
6898 case elfcpp::Tag_T2EE_use
:
6899 case elfcpp::Tag_Virtualization_use
:
6900 case elfcpp::Tag_MPextension_use
:
6901 // Use the largest value specified.
6902 if (in_attr
[i
].int_value() > out_attr
[i
].int_value())
6903 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
6906 case elfcpp::Tag_ABI_align8_preserved
:
6907 case elfcpp::Tag_ABI_PCS_RO_data
:
6908 // Use the smallest value specified.
6909 if (in_attr
[i
].int_value() < out_attr
[i
].int_value())
6910 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
6913 case elfcpp::Tag_ABI_align8_needed
:
6914 if ((in_attr
[i
].int_value() > 0 || out_attr
[i
].int_value() > 0)
6915 && (in_attr
[elfcpp::Tag_ABI_align8_preserved
].int_value() == 0
6916 || (out_attr
[elfcpp::Tag_ABI_align8_preserved
].int_value()
6919 // This error message should be enabled once all non-conformant
6920 // binaries in the toolchain have had the attributes set
6922 // gold_error(_("output 8-byte data alignment conflicts with %s"),
6926 case elfcpp::Tag_ABI_FP_denormal
:
6927 case elfcpp::Tag_ABI_PCS_GOT_use
:
6929 // These tags have 0 = don't care, 1 = strong requirement,
6930 // 2 = weak requirement.
6931 static const int order_021
[3] = {0, 2, 1};
6933 // Use the "greatest" from the sequence 0, 2, 1, or the largest
6934 // value if greater than 2 (for future-proofing).
6935 if ((in_attr
[i
].int_value() > 2
6936 && in_attr
[i
].int_value() > out_attr
[i
].int_value())
6937 || (in_attr
[i
].int_value() <= 2
6938 && out_attr
[i
].int_value() <= 2
6939 && (order_021
[in_attr
[i
].int_value()]
6940 > order_021
[out_attr
[i
].int_value()])))
6941 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
6945 case elfcpp::Tag_CPU_arch_profile
:
6946 if (out_attr
[i
].int_value() != in_attr
[i
].int_value())
6948 // 0 will merge with anything.
6949 // 'A' and 'S' merge to 'A'.
6950 // 'R' and 'S' merge to 'R'.
6951 // 'M' and 'A|R|S' is an error.
6952 if (out_attr
[i
].int_value() == 0
6953 || (out_attr
[i
].int_value() == 'S'
6954 && (in_attr
[i
].int_value() == 'A'
6955 || in_attr
[i
].int_value() == 'R')))
6956 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
6957 else if (in_attr
[i
].int_value() == 0
6958 || (in_attr
[i
].int_value() == 'S'
6959 && (out_attr
[i
].int_value() == 'A'
6960 || out_attr
[i
].int_value() == 'R')))
6965 (_("conflicting architecture profiles %c/%c"),
6966 in_attr
[i
].int_value() ? in_attr
[i
].int_value() : '0',
6967 out_attr
[i
].int_value() ? out_attr
[i
].int_value() : '0');
6971 case elfcpp::Tag_VFP_arch
:
6988 // Values greater than 6 aren't defined, so just pick the
6990 if (in_attr
[i
].int_value() > 6
6991 && in_attr
[i
].int_value() > out_attr
[i
].int_value())
6993 *out_attr
= *in_attr
;
6996 // The output uses the superset of input features
6997 // (ISA version) and registers.
6998 int ver
= std::max(vfp_versions
[in_attr
[i
].int_value()].ver
,
6999 vfp_versions
[out_attr
[i
].int_value()].ver
);
7000 int regs
= std::max(vfp_versions
[in_attr
[i
].int_value()].regs
,
7001 vfp_versions
[out_attr
[i
].int_value()].regs
);
7002 // This assumes all possible supersets are also a valid
7005 for (newval
= 6; newval
> 0; newval
--)
7007 if (regs
== vfp_versions
[newval
].regs
7008 && ver
== vfp_versions
[newval
].ver
)
7011 out_attr
[i
].set_int_value(newval
);
7014 case elfcpp::Tag_PCS_config
:
7015 if (out_attr
[i
].int_value() == 0)
7016 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7017 else if (in_attr
[i
].int_value() != 0 && out_attr
[i
].int_value() != 0)
7019 // It's sometimes ok to mix different configs, so this is only
7021 gold_warning(_("%s: conflicting platform configuration"), name
);
7024 case elfcpp::Tag_ABI_PCS_R9_use
:
7025 if (in_attr
[i
].int_value() != out_attr
[i
].int_value()
7026 && out_attr
[i
].int_value() != elfcpp::AEABI_R9_unused
7027 && in_attr
[i
].int_value() != elfcpp::AEABI_R9_unused
)
7029 gold_error(_("%s: conflicting use of R9"), name
);
7031 if (out_attr
[i
].int_value() == elfcpp::AEABI_R9_unused
)
7032 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7034 case elfcpp::Tag_ABI_PCS_RW_data
:
7035 if (in_attr
[i
].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
7036 && (in_attr
[elfcpp::Tag_ABI_PCS_R9_use
].int_value()
7037 != elfcpp::AEABI_R9_SB
)
7038 && (out_attr
[elfcpp::Tag_ABI_PCS_R9_use
].int_value()
7039 != elfcpp::AEABI_R9_unused
))
7041 gold_error(_("%s: SB relative addressing conflicts with use "
7045 // Use the smallest value specified.
7046 if (in_attr
[i
].int_value() < out_attr
[i
].int_value())
7047 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7049 case elfcpp::Tag_ABI_PCS_wchar_t
:
7050 // FIXME: Make it possible to turn off this warning.
7051 if (out_attr
[i
].int_value()
7052 && in_attr
[i
].int_value()
7053 && out_attr
[i
].int_value() != in_attr
[i
].int_value())
7055 gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
7056 "use %u-byte wchar_t; use of wchar_t values "
7057 "across objects may fail"),
7058 name
, in_attr
[i
].int_value(),
7059 out_attr
[i
].int_value());
7061 else if (in_attr
[i
].int_value() && !out_attr
[i
].int_value())
7062 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7064 case elfcpp::Tag_ABI_enum_size
:
7065 if (in_attr
[i
].int_value() != elfcpp::AEABI_enum_unused
)
7067 if (out_attr
[i
].int_value() == elfcpp::AEABI_enum_unused
7068 || out_attr
[i
].int_value() == elfcpp::AEABI_enum_forced_wide
)
7070 // The existing object is compatible with anything.
7071 // Use whatever requirements the new object has.
7072 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7074 // FIXME: Make it possible to turn off this warning.
7075 else if (in_attr
[i
].int_value() != elfcpp::AEABI_enum_forced_wide
7076 && out_attr
[i
].int_value() != in_attr
[i
].int_value())
7078 unsigned int in_value
= in_attr
[i
].int_value();
7079 unsigned int out_value
= out_attr
[i
].int_value();
7080 gold_warning(_("%s uses %s enums yet the output is to use "
7081 "%s enums; use of enum values across objects "
7084 this->aeabi_enum_name(in_value
).c_str(),
7085 this->aeabi_enum_name(out_value
).c_str());
7089 case elfcpp::Tag_ABI_VFP_args
:
7092 case elfcpp::Tag_ABI_WMMX_args
:
7093 if (in_attr
[i
].int_value() != out_attr
[i
].int_value())
7095 gold_error(_("%s uses iWMMXt register arguments, output does "
7100 case Object_attribute::Tag_compatibility
:
7101 // Merged in target-independent code.
7103 case elfcpp::Tag_ABI_HardFP_use
:
7104 // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
7105 if ((in_attr
[i
].int_value() == 1 && out_attr
[i
].int_value() == 2)
7106 || (in_attr
[i
].int_value() == 2 && out_attr
[i
].int_value() == 1))
7107 out_attr
[i
].set_int_value(3);
7108 else if (in_attr
[i
].int_value() > out_attr
[i
].int_value())
7109 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7111 case elfcpp::Tag_ABI_FP_16bit_format
:
7112 if (in_attr
[i
].int_value() != 0 && out_attr
[i
].int_value() != 0)
7114 if (in_attr
[i
].int_value() != out_attr
[i
].int_value())
7115 gold_error(_("fp16 format mismatch between %s and output"),
7118 if (in_attr
[i
].int_value() != 0)
7119 out_attr
[i
].set_int_value(in_attr
[i
].int_value());
7122 case elfcpp::Tag_nodefaults
:
7123 // This tag is set if it exists, but the value is unused (and is
7124 // typically zero). We don't actually need to do anything here -
7125 // the merge happens automatically when the type flags are merged
7128 case elfcpp::Tag_also_compatible_with
:
7129 // Already done in Tag_CPU_arch.
7131 case elfcpp::Tag_conformance
:
7132 // Keep the attribute if it matches. Throw it away otherwise.
7133 // No attribute means no claim to conform.
7134 if (in_attr
[i
].string_value() != out_attr
[i
].string_value())
7135 out_attr
[i
].set_string_value("");
7140 const char* err_object
= NULL
;
7142 // The "known_obj_attributes" table does contain some undefined
7143 // attributes. Ensure that there are unused.
7144 if (out_attr
[i
].int_value() != 0
7145 || out_attr
[i
].string_value() != "")
7146 err_object
= "output";
7147 else if (in_attr
[i
].int_value() != 0
7148 || in_attr
[i
].string_value() != "")
7151 if (err_object
!= NULL
)
7153 // Attribute numbers >=64 (mod 128) can be safely ignored.
7155 gold_error(_("%s: unknown mandatory EABI object attribute "
7159 gold_warning(_("%s: unknown EABI object attribute %d"),
7163 // Only pass on attributes that match in both inputs.
7164 if (!in_attr
[i
].matches(out_attr
[i
]))
7166 out_attr
[i
].set_int_value(0);
7167 out_attr
[i
].set_string_value("");
7172 // If out_attr was copied from in_attr then it won't have a type yet.
7173 if (in_attr
[i
].type() && !out_attr
[i
].type())
7174 out_attr
[i
].set_type(in_attr
[i
].type());
7177 // Merge Tag_compatibility attributes and any common GNU ones.
7178 this->attributes_section_data_
->merge(name
, pasd
);
7180 // Check for any attributes not known on ARM.
7181 typedef Vendor_object_attributes::Other_attributes Other_attributes
;
7182 const Other_attributes
* in_other_attributes
= pasd
->other_attributes(vendor
);
7183 Other_attributes::const_iterator in_iter
= in_other_attributes
->begin();
7184 Other_attributes
* out_other_attributes
=
7185 this->attributes_section_data_
->other_attributes(vendor
);
7186 Other_attributes::iterator out_iter
= out_other_attributes
->begin();
7188 while (in_iter
!= in_other_attributes
->end()
7189 || out_iter
!= out_other_attributes
->end())
7191 const char* err_object
= NULL
;
7194 // The tags for each list are in numerical order.
7195 // If the tags are equal, then merge.
7196 if (out_iter
!= out_other_attributes
->end()
7197 && (in_iter
== in_other_attributes
->end()
7198 || in_iter
->first
> out_iter
->first
))
7200 // This attribute only exists in output. We can't merge, and we
7201 // don't know what the tag means, so delete it.
7202 err_object
= "output";
7203 err_tag
= out_iter
->first
;
7204 int saved_tag
= out_iter
->first
;
7205 delete out_iter
->second
;
7206 out_other_attributes
->erase(out_iter
);
7207 out_iter
= out_other_attributes
->upper_bound(saved_tag
);
7209 else if (in_iter
!= in_other_attributes
->end()
7210 && (out_iter
!= out_other_attributes
->end()
7211 || in_iter
->first
< out_iter
->first
))
7213 // This attribute only exists in input. We can't merge, and we
7214 // don't know what the tag means, so ignore it.
7216 err_tag
= in_iter
->first
;
7219 else // The tags are equal.
7221 // As present, all attributes in the list are unknown, and
7222 // therefore can't be merged meaningfully.
7223 err_object
= "output";
7224 err_tag
= out_iter
->first
;
7226 // Only pass on attributes that match in both inputs.
7227 if (!in_iter
->second
->matches(*(out_iter
->second
)))
7229 // No match. Delete the attribute.
7230 int saved_tag
= out_iter
->first
;
7231 delete out_iter
->second
;
7232 out_other_attributes
->erase(out_iter
);
7233 out_iter
= out_other_attributes
->upper_bound(saved_tag
);
7237 // Matched. Keep the attribute and move to the next.
7245 // Attribute numbers >=64 (mod 128) can be safely ignored. */
7246 if ((err_tag
& 127) < 64)
7248 gold_error(_("%s: unknown mandatory EABI object attribute %d"),
7249 err_object
, err_tag
);
7253 gold_warning(_("%s: unknown EABI object attribute %d"),
7254 err_object
, err_tag
);
7260 // Return whether a relocation type used the LSB to distinguish THUMB
7262 template<bool big_endian
>
7264 Target_arm
<big_endian
>::reloc_uses_thumb_bit(unsigned int r_type
)
7268 case elfcpp::R_ARM_PC24
:
7269 case elfcpp::R_ARM_ABS32
:
7270 case elfcpp::R_ARM_REL32
:
7271 case elfcpp::R_ARM_SBREL32
:
7272 case elfcpp::R_ARM_THM_CALL
:
7273 case elfcpp::R_ARM_GLOB_DAT
:
7274 case elfcpp::R_ARM_JUMP_SLOT
:
7275 case elfcpp::R_ARM_GOTOFF32
:
7276 case elfcpp::R_ARM_PLT32
:
7277 case elfcpp::R_ARM_CALL
:
7278 case elfcpp::R_ARM_JUMP24
:
7279 case elfcpp::R_ARM_THM_JUMP24
:
7280 case elfcpp::R_ARM_SBREL31
:
7281 case elfcpp::R_ARM_PREL31
:
7282 case elfcpp::R_ARM_MOVW_ABS_NC
:
7283 case elfcpp::R_ARM_MOVW_PREL_NC
:
7284 case elfcpp::R_ARM_THM_MOVW_ABS_NC
:
7285 case elfcpp::R_ARM_THM_MOVW_PREL_NC
:
7286 case elfcpp::R_ARM_THM_JUMP19
:
7287 case elfcpp::R_ARM_THM_ALU_PREL_11_0
:
7288 case elfcpp::R_ARM_ALU_PC_G0_NC
:
7289 case elfcpp::R_ARM_ALU_PC_G0
:
7290 case elfcpp::R_ARM_ALU_PC_G1_NC
:
7291 case elfcpp::R_ARM_ALU_PC_G1
:
7292 case elfcpp::R_ARM_ALU_PC_G2
:
7293 case elfcpp::R_ARM_ALU_SB_G0_NC
:
7294 case elfcpp::R_ARM_ALU_SB_G0
:
7295 case elfcpp::R_ARM_ALU_SB_G1_NC
:
7296 case elfcpp::R_ARM_ALU_SB_G1
:
7297 case elfcpp::R_ARM_ALU_SB_G2
:
7298 case elfcpp::R_ARM_MOVW_BREL_NC
:
7299 case elfcpp::R_ARM_MOVW_BREL
:
7300 case elfcpp::R_ARM_THM_MOVW_BREL_NC
:
7301 case elfcpp::R_ARM_THM_MOVW_BREL
:
7308 // Stub-generation methods for Target_arm.
7310 // Make a new Arm_input_section object.
7312 template<bool big_endian
>
7313 Arm_input_section
<big_endian
>*
7314 Target_arm
<big_endian
>::new_arm_input_section(
7318 Input_section_specifier
iss(relobj
, shndx
);
7320 Arm_input_section
<big_endian
>* arm_input_section
=
7321 new Arm_input_section
<big_endian
>(relobj
, shndx
);
7322 arm_input_section
->init();
7324 // Register new Arm_input_section in map for look-up.
7325 std::pair
<typename
Arm_input_section_map::iterator
, bool> ins
=
7326 this->arm_input_section_map_
.insert(std::make_pair(iss
, arm_input_section
));
7328 // Make sure that it we have not created another Arm_input_section
7329 // for this input section already.
7330 gold_assert(ins
.second
);
7332 return arm_input_section
;
7335 // Find the Arm_input_section object corresponding to the SHNDX-th input
7336 // section of RELOBJ.
7338 template<bool big_endian
>
7339 Arm_input_section
<big_endian
>*
7340 Target_arm
<big_endian
>::find_arm_input_section(
7342 unsigned int shndx
) const
7344 Input_section_specifier
iss(relobj
, shndx
);
7345 typename
Arm_input_section_map::const_iterator p
=
7346 this->arm_input_section_map_
.find(iss
);
7347 return (p
!= this->arm_input_section_map_
.end()) ? p
->second
: NULL
;
7350 // Make a new stub table.
7352 template<bool big_endian
>
7353 Stub_table
<big_endian
>*
7354 Target_arm
<big_endian
>::new_stub_table(Arm_input_section
<big_endian
>* owner
)
7356 Stub_table
<big_endian
>* stub_table
=
7357 new Stub_table
<big_endian
>(owner
);
7358 this->stub_tables_
.push_back(stub_table
);
7360 stub_table
->set_address(owner
->address() + owner
->data_size());
7361 stub_table
->set_file_offset(owner
->offset() + owner
->data_size());
7362 stub_table
->finalize_data_size();
7367 // Scan a relocation for stub generation.
7369 template<bool big_endian
>
7371 Target_arm
<big_endian
>::scan_reloc_for_stub(
7372 const Relocate_info
<32, big_endian
>* relinfo
,
7373 unsigned int r_type
,
7374 const Sized_symbol
<32>* gsym
,
7376 const Symbol_value
<32>* psymval
,
7377 elfcpp::Elf_types
<32>::Elf_Swxword addend
,
7378 Arm_address address
)
7380 typedef typename Target_arm
<big_endian
>::Relocate Relocate
;
7382 const Arm_relobj
<big_endian
>* arm_relobj
=
7383 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
7385 bool target_is_thumb
;
7386 Symbol_value
<32> symval
;
7389 // This is a global symbol. Determine if we use PLT and if the
7390 // final target is THUMB.
7391 if (gsym
->use_plt_offset(Relocate::reloc_is_non_pic(r_type
)))
7393 // This uses a PLT, change the symbol value.
7394 symval
.set_output_value(this->plt_section()->address()
7395 + gsym
->plt_offset());
7397 target_is_thumb
= false;
7399 else if (gsym
->is_undefined())
7400 // There is no need to generate a stub symbol is undefined.
7405 ((gsym
->type() == elfcpp::STT_ARM_TFUNC
)
7406 || (gsym
->type() == elfcpp::STT_FUNC
7407 && !gsym
->is_undefined()
7408 && ((psymval
->value(arm_relobj
, 0) & 1) != 0)));
7413 // This is a local symbol. Determine if the final target is THUMB.
7414 target_is_thumb
= arm_relobj
->local_symbol_is_thumb_function(r_sym
);
7417 // Strip LSB if this points to a THUMB target.
7419 && Target_arm
<big_endian
>::reloc_uses_thumb_bit(r_type
)
7420 && ((psymval
->value(arm_relobj
, 0) & 1) != 0))
7422 Arm_address stripped_value
=
7423 psymval
->value(arm_relobj
, 0) & ~static_cast<Arm_address
>(1);
7424 symval
.set_output_value(stripped_value
);
7428 // Get the symbol value.
7429 Symbol_value
<32>::Value value
= psymval
->value(arm_relobj
, 0);
7431 // Owing to pipelining, the PC relative branches below actually skip
7432 // two instructions when the branch offset is 0.
7433 Arm_address destination
;
7436 case elfcpp::R_ARM_CALL
:
7437 case elfcpp::R_ARM_JUMP24
:
7438 case elfcpp::R_ARM_PLT32
:
7440 destination
= value
+ addend
+ 8;
7442 case elfcpp::R_ARM_THM_CALL
:
7443 case elfcpp::R_ARM_THM_XPC22
:
7444 case elfcpp::R_ARM_THM_JUMP24
:
7445 case elfcpp::R_ARM_THM_JUMP19
:
7447 destination
= value
+ addend
+ 4;
7453 Reloc_stub
* stub
= NULL
;
7454 Stub_type stub_type
=
7455 Reloc_stub::stub_type_for_reloc(r_type
, address
, destination
,
7457 if (stub_type
!= arm_stub_none
)
7459 // Try looking up an existing stub from a stub table.
7460 Stub_table
<big_endian
>* stub_table
=
7461 arm_relobj
->stub_table(relinfo
->data_shndx
);
7462 gold_assert(stub_table
!= NULL
);
7464 // Locate stub by destination.
7465 Reloc_stub::Key
stub_key(stub_type
, gsym
, arm_relobj
, r_sym
, addend
);
7467 // Create a stub if there is not one already
7468 stub
= stub_table
->find_reloc_stub(stub_key
);
7471 // create a new stub and add it to stub table.
7472 stub
= this->stub_factory().make_reloc_stub(stub_type
);
7473 stub_table
->add_reloc_stub(stub
, stub_key
);
7476 // Record the destination address.
7477 stub
->set_destination_address(destination
7478 | (target_is_thumb
? 1 : 0));
7481 // For Cortex-A8, we need to record a relocation at 4K page boundary.
7482 if (this->fix_cortex_a8_
7483 && (r_type
== elfcpp::R_ARM_THM_JUMP24
7484 || r_type
== elfcpp::R_ARM_THM_JUMP19
7485 || r_type
== elfcpp::R_ARM_THM_CALL
7486 || r_type
== elfcpp::R_ARM_THM_XPC22
)
7487 && (address
& 0xfffU
) == 0xffeU
)
7489 // Found a candidate. Note we haven't checked the destination is
7490 // within 4K here: if we do so (and don't create a record) we can't
7491 // tell that a branch should have been relocated when scanning later.
7492 this->cortex_a8_relocs_info_
[address
] =
7493 new Cortex_a8_reloc(stub
, r_type
,
7494 destination
| (target_is_thumb
? 1 : 0));
7498 // This function scans a relocation sections for stub generation.
7499 // The template parameter Relocate must be a class type which provides
7500 // a single function, relocate(), which implements the machine
7501 // specific part of a relocation.
7503 // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
7504 // SHT_REL or SHT_RELA.
7506 // PRELOCS points to the relocation data. RELOC_COUNT is the number
7507 // of relocs. OUTPUT_SECTION is the output section.
7508 // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
7509 // mapped to output offsets.
7511 // VIEW is the section data, VIEW_ADDRESS is its memory address, and
7512 // VIEW_SIZE is the size. These refer to the input section, unless
7513 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
7514 // the output section.
7516 template<bool big_endian
>
7517 template<int sh_type
>
7519 Target_arm
<big_endian
>::scan_reloc_section_for_stubs(
7520 const Relocate_info
<32, big_endian
>* relinfo
,
7521 const unsigned char* prelocs
,
7523 Output_section
* output_section
,
7524 bool needs_special_offset_handling
,
7525 const unsigned char* view
,
7526 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
7529 typedef typename Reloc_types
<sh_type
, 32, big_endian
>::Reloc Reltype
;
7530 const int reloc_size
=
7531 Reloc_types
<sh_type
, 32, big_endian
>::reloc_size
;
7533 Arm_relobj
<big_endian
>* arm_object
=
7534 Arm_relobj
<big_endian
>::as_arm_relobj(relinfo
->object
);
7535 unsigned int local_count
= arm_object
->local_symbol_count();
7537 Comdat_behavior comdat_behavior
= CB_UNDETERMINED
;
7539 for (size_t i
= 0; i
< reloc_count
; ++i
, prelocs
+= reloc_size
)
7541 Reltype
reloc(prelocs
);
7543 typename
elfcpp::Elf_types
<32>::Elf_WXword r_info
= reloc
.get_r_info();
7544 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(r_info
);
7545 unsigned int r_type
= elfcpp::elf_r_type
<32>(r_info
);
7547 r_type
= this->get_real_reloc_type(r_type
);
7549 // Only a few relocation types need stubs.
7550 if ((r_type
!= elfcpp::R_ARM_CALL
)
7551 && (r_type
!= elfcpp::R_ARM_JUMP24
)
7552 && (r_type
!= elfcpp::R_ARM_PLT32
)
7553 && (r_type
!= elfcpp::R_ARM_THM_CALL
)
7554 && (r_type
!= elfcpp::R_ARM_THM_XPC22
)
7555 && (r_type
!= elfcpp::R_ARM_THM_JUMP24
)
7556 && (r_type
!= elfcpp::R_ARM_THM_JUMP19
))
7559 section_offset_type offset
=
7560 convert_to_section_size_type(reloc
.get_r_offset());
7562 if (needs_special_offset_handling
)
7564 offset
= output_section
->output_offset(relinfo
->object
,
7565 relinfo
->data_shndx
,
7572 Stub_addend_reader
<sh_type
, big_endian
> stub_addend_reader
;
7573 elfcpp::Elf_types
<32>::Elf_Swxword addend
=
7574 stub_addend_reader(r_type
, view
+ offset
, reloc
);
7576 const Sized_symbol
<32>* sym
;
7578 Symbol_value
<32> symval
;
7579 const Symbol_value
<32> *psymval
;
7580 if (r_sym
< local_count
)
7583 psymval
= arm_object
->local_symbol(r_sym
);
7585 // If the local symbol belongs to a section we are discarding,
7586 // and that section is a debug section, try to find the
7587 // corresponding kept section and map this symbol to its
7588 // counterpart in the kept section. The symbol must not
7589 // correspond to a section we are folding.
7591 unsigned int shndx
= psymval
->input_shndx(&is_ordinary
);
7593 && shndx
!= elfcpp::SHN_UNDEF
7594 && !arm_object
->is_section_included(shndx
)
7595 && !(relinfo
->symtab
->is_section_folded(arm_object
, shndx
)))
7597 if (comdat_behavior
== CB_UNDETERMINED
)
7600 arm_object
->section_name(relinfo
->data_shndx
);
7601 comdat_behavior
= get_comdat_behavior(name
.c_str());
7603 if (comdat_behavior
== CB_PRETEND
)
7606 typename
elfcpp::Elf_types
<32>::Elf_Addr value
=
7607 arm_object
->map_to_kept_section(shndx
, &found
);
7609 symval
.set_output_value(value
+ psymval
->input_value());
7611 symval
.set_output_value(0);
7615 symval
.set_output_value(0);
7617 symval
.set_no_output_symtab_entry();
7623 const Symbol
* gsym
= arm_object
->global_symbol(r_sym
);
7624 gold_assert(gsym
!= NULL
);
7625 if (gsym
->is_forwarder())
7626 gsym
= relinfo
->symtab
->resolve_forwards(gsym
);
7628 sym
= static_cast<const Sized_symbol
<32>*>(gsym
);
7629 if (sym
->has_symtab_index())
7630 symval
.set_output_symtab_index(sym
->symtab_index());
7632 symval
.set_no_output_symtab_entry();
7634 // We need to compute the would-be final value of this global
7636 const Symbol_table
* symtab
= relinfo
->symtab
;
7637 const Sized_symbol
<32>* sized_symbol
=
7638 symtab
->get_sized_symbol
<32>(gsym
);
7639 Symbol_table::Compute_final_value_status status
;
7641 symtab
->compute_final_value
<32>(sized_symbol
, &status
);
7643 // Skip this if the symbol has not output section.
7644 if (status
== Symbol_table::CFVS_NO_OUTPUT_SECTION
)
7647 symval
.set_output_value(value
);
7651 // If symbol is a section symbol, we don't know the actual type of
7652 // destination. Give up.
7653 if (psymval
->is_section_symbol())
7656 this->scan_reloc_for_stub(relinfo
, r_type
, sym
, r_sym
, psymval
,
7657 addend
, view_address
+ offset
);
7661 // Scan an input section for stub generation.
7663 template<bool big_endian
>
7665 Target_arm
<big_endian
>::scan_section_for_stubs(
7666 const Relocate_info
<32, big_endian
>* relinfo
,
7667 unsigned int sh_type
,
7668 const unsigned char* prelocs
,
7670 Output_section
* output_section
,
7671 bool needs_special_offset_handling
,
7672 const unsigned char* view
,
7673 Arm_address view_address
,
7674 section_size_type view_size
)
7676 if (sh_type
== elfcpp::SHT_REL
)
7677 this->scan_reloc_section_for_stubs
<elfcpp::SHT_REL
>(
7682 needs_special_offset_handling
,
7686 else if (sh_type
== elfcpp::SHT_RELA
)
7687 // We do not support RELA type relocations yet. This is provided for
7689 this->scan_reloc_section_for_stubs
<elfcpp::SHT_RELA
>(
7694 needs_special_offset_handling
,
7702 // Group input sections for stub generation.
7704 // We goup input sections in an output sections so that the total size,
7705 // including any padding space due to alignment is smaller than GROUP_SIZE
7706 // unless the only input section in group is bigger than GROUP_SIZE already.
7707 // Then an ARM stub table is created to follow the last input section
7708 // in group. For each group an ARM stub table is created an is placed
7709 // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
7710 // extend the group after the stub table.
7712 template<bool big_endian
>
7714 Target_arm
<big_endian
>::group_sections(
7716 section_size_type group_size
,
7717 bool stubs_always_after_branch
)
7719 // Group input sections and insert stub table
7720 Layout::Section_list section_list
;
7721 layout
->get_allocated_sections(§ion_list
);
7722 for (Layout::Section_list::const_iterator p
= section_list
.begin();
7723 p
!= section_list
.end();
7726 Arm_output_section
<big_endian
>* output_section
=
7727 Arm_output_section
<big_endian
>::as_arm_output_section(*p
);
7728 output_section
->group_sections(group_size
, stubs_always_after_branch
,
7733 // Relaxation hook. This is where we do stub generation.
7735 template<bool big_endian
>
7737 Target_arm
<big_endian
>::do_relax(
7739 const Input_objects
* input_objects
,
7740 Symbol_table
* symtab
,
7743 // No need to generate stubs if this is a relocatable link.
7744 gold_assert(!parameters
->options().relocatable());
7746 // If this is the first pass, we need to group input sections into
7750 // Determine the stub group size. The group size is the absolute
7751 // value of the parameter --stub-group-size. If --stub-group-size
7752 // is passed a negative value, we restict stubs to be always after
7753 // the stubbed branches.
7754 int32_t stub_group_size_param
=
7755 parameters
->options().stub_group_size();
7756 bool stubs_always_after_branch
= stub_group_size_param
< 0;
7757 section_size_type stub_group_size
= abs(stub_group_size_param
);
7759 // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
7760 // page as the first half of a 32-bit branch straddling two 4K pages.
7761 // This is a crude way of enforcing that.
7762 if (this->fix_cortex_a8_
)
7763 stubs_always_after_branch
= true;
7765 if (stub_group_size
== 1)
7768 // Thumb branch range is +-4MB has to be used as the default
7769 // maximum size (a given section can contain both ARM and Thumb
7770 // code, so the worst case has to be taken into account).
7772 // This value is 24K less than that, which allows for 2025
7773 // 12-byte stubs. If we exceed that, then we will fail to link.
7774 // The user will have to relink with an explicit group size
7776 stub_group_size
= 4170000;
7779 group_sections(layout
, stub_group_size
, stubs_always_after_branch
);
7782 // The Cortex-A8 stubs are sensitive to layout of code sections. At the
7783 // beginning of each relaxation pass, just blow away all the stubs.
7784 // Alternatively, we could selectively remove only the stubs and reloc
7785 // information for code sections that have moved since the last pass.
7786 // That would require more book-keeping.
7787 typedef typename
Stub_table_list::iterator Stub_table_iterator
;
7788 if (this->fix_cortex_a8_
)
7790 // Clear all Cortex-A8 reloc information.
7791 for (typename
Cortex_a8_relocs_info::const_iterator p
=
7792 this->cortex_a8_relocs_info_
.begin();
7793 p
!= this->cortex_a8_relocs_info_
.end();
7796 this->cortex_a8_relocs_info_
.clear();
7798 // Remove all Cortex-A8 stubs.
7799 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
7800 sp
!= this->stub_tables_
.end();
7802 (*sp
)->remove_all_cortex_a8_stubs();
7805 // Scan relocs for relocation stubs
7806 for (Input_objects::Relobj_iterator op
= input_objects
->relobj_begin();
7807 op
!= input_objects
->relobj_end();
7810 Arm_relobj
<big_endian
>* arm_relobj
=
7811 Arm_relobj
<big_endian
>::as_arm_relobj(*op
);
7812 arm_relobj
->scan_sections_for_stubs(this, symtab
, layout
);
7815 // Check all stub tables to see if any of them have their data sizes
7816 // or addresses alignments changed. These are the only things that
7818 bool any_stub_table_changed
= false;
7819 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
7820 (sp
!= this->stub_tables_
.end()) && !any_stub_table_changed
;
7823 if ((*sp
)->update_data_size_and_addralign())
7824 any_stub_table_changed
= true;
7827 // Finalize the stubs in the last relaxation pass.
7828 if (!any_stub_table_changed
)
7829 for (Stub_table_iterator sp
= this->stub_tables_
.begin();
7830 (sp
!= this->stub_tables_
.end()) && !any_stub_table_changed
;
7832 (*sp
)->finalize_stubs();
7834 return any_stub_table_changed
;
7839 template<bool big_endian
>
7841 Target_arm
<big_endian
>::relocate_stub(
7843 const Relocate_info
<32, big_endian
>* relinfo
,
7844 Output_section
* output_section
,
7845 unsigned char* view
,
7846 Arm_address address
,
7847 section_size_type view_size
)
7850 const Stub_template
* stub_template
= stub
->stub_template();
7851 for (size_t i
= 0; i
< stub_template
->reloc_count(); i
++)
7853 size_t reloc_insn_index
= stub_template
->reloc_insn_index(i
);
7854 const Insn_template
* insn
= &stub_template
->insns()[reloc_insn_index
];
7856 unsigned int r_type
= insn
->r_type();
7857 section_size_type reloc_offset
= stub_template
->reloc_offset(i
);
7858 section_size_type reloc_size
= insn
->size();
7859 gold_assert(reloc_offset
+ reloc_size
<= view_size
);
7861 // This is the address of the stub destination.
7862 Arm_address target
= stub
->reloc_target(i
) + insn
->reloc_addend();
7863 Symbol_value
<32> symval
;
7864 symval
.set_output_value(target
);
7866 // Synthesize a fake reloc just in case. We don't have a symbol so
7868 unsigned char reloc_buffer
[elfcpp::Elf_sizes
<32>::rel_size
];
7869 memset(reloc_buffer
, 0, sizeof(reloc_buffer
));
7870 elfcpp::Rel_write
<32, big_endian
> reloc_write(reloc_buffer
);
7871 reloc_write
.put_r_offset(reloc_offset
);
7872 reloc_write
.put_r_info(elfcpp::elf_r_info
<32>(0, r_type
));
7873 elfcpp::Rel
<32, big_endian
> rel(reloc_buffer
);
7875 relocate
.relocate(relinfo
, this, output_section
,
7876 this->fake_relnum_for_stubs
, rel
, r_type
,
7877 NULL
, &symval
, view
+ reloc_offset
,
7878 address
+ reloc_offset
, reloc_size
);
7882 // Determine whether an object attribute tag takes an integer, a
7885 template<bool big_endian
>
7887 Target_arm
<big_endian
>::do_attribute_arg_type(int tag
) const
7889 if (tag
== Object_attribute::Tag_compatibility
)
7890 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
7891 | Object_attribute::ATTR_TYPE_FLAG_STR_VAL
);
7892 else if (tag
== elfcpp::Tag_nodefaults
)
7893 return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
7894 | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT
);
7895 else if (tag
== elfcpp::Tag_CPU_raw_name
|| tag
== elfcpp::Tag_CPU_name
)
7896 return Object_attribute::ATTR_TYPE_FLAG_STR_VAL
;
7898 return Object_attribute::ATTR_TYPE_FLAG_INT_VAL
;
7900 return ((tag
& 1) != 0
7901 ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
7902 : Object_attribute::ATTR_TYPE_FLAG_INT_VAL
);
7905 // Reorder attributes.
7907 // The ABI defines that Tag_conformance should be emitted first, and that
7908 // Tag_nodefaults should be second (if either is defined). This sets those
7909 // two positions, and bumps up the position of all the remaining tags to
7912 template<bool big_endian
>
7914 Target_arm
<big_endian
>::do_attributes_order(int num
) const
7916 // Reorder the known object attributes in output. We want to move
7917 // Tag_conformance to position 4 and Tag_conformance to position 5
7918 // and shift eveything between 4 .. Tag_conformance - 1 to make room.
7920 return elfcpp::Tag_conformance
;
7922 return elfcpp::Tag_nodefaults
;
7923 if ((num
- 2) < elfcpp::Tag_nodefaults
)
7925 if ((num
- 1) < elfcpp::Tag_conformance
)
7930 // Scan a span of THUMB code for Cortex-A8 erratum.
7932 template<bool big_endian
>
7934 Target_arm
<big_endian
>::scan_span_for_cortex_a8_erratum(
7935 Arm_relobj
<big_endian
>* arm_relobj
,
7937 section_size_type span_start
,
7938 section_size_type span_end
,
7939 const unsigned char* view
,
7940 Arm_address address
)
7942 // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
7944 // The opcode is BLX.W, BL.W, B.W, Bcc.W
7945 // The branch target is in the same 4KB region as the
7946 // first half of the branch.
7947 // The instruction before the branch is a 32-bit
7948 // length non-branch instruction.
7949 section_size_type i
= span_start
;
7950 bool last_was_32bit
= false;
7951 bool last_was_branch
= false;
7952 while (i
< span_end
)
7954 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
7955 const Valtype
* wv
= reinterpret_cast<const Valtype
*>(view
+ i
);
7956 uint32_t insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
7957 bool is_blx
= false, is_b
= false;
7958 bool is_bl
= false, is_bcc
= false;
7960 bool insn_32bit
= (insn
& 0xe000) == 0xe000 && (insn
& 0x1800) != 0x0000;
7963 // Load the rest of the insn (in manual-friendly order).
7964 insn
= (insn
<< 16) | elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
7966 // Encoding T4: B<c>.W.
7967 is_b
= (insn
& 0xf800d000U
) == 0xf0009000U
;
7968 // Encoding T1: BL<c>.W.
7969 is_bl
= (insn
& 0xf800d000U
) == 0xf000d000U
;
7970 // Encoding T2: BLX<c>.W.
7971 is_blx
= (insn
& 0xf800d000U
) == 0xf000c000U
;
7972 // Encoding T3: B<c>.W (not permitted in IT block).
7973 is_bcc
= ((insn
& 0xf800d000U
) == 0xf0008000U
7974 && (insn
& 0x07f00000U
) != 0x03800000U
);
7977 bool is_32bit_branch
= is_b
|| is_bl
|| is_blx
|| is_bcc
;
7979 // If this instruction is a 32-bit THUMB branch that crosses a 4K
7980 // page boundary and it follows 32-bit non-branch instruction,
7981 // we need to work around.
7983 && ((address
+ i
) & 0xfffU
) == 0xffeU
7985 && !last_was_branch
)
7987 // Check to see if there is a relocation stub for this branch.
7988 bool force_target_arm
= false;
7989 bool force_target_thumb
= false;
7990 const Cortex_a8_reloc
* cortex_a8_reloc
= NULL
;
7991 Cortex_a8_relocs_info::const_iterator p
=
7992 this->cortex_a8_relocs_info_
.find(address
+ i
);
7994 if (p
!= this->cortex_a8_relocs_info_
.end())
7996 cortex_a8_reloc
= p
->second
;
7997 bool target_is_thumb
= (cortex_a8_reloc
->destination() & 1) != 0;
7999 if (cortex_a8_reloc
->r_type() == elfcpp::R_ARM_THM_CALL
8000 && !target_is_thumb
)
8001 force_target_arm
= true;
8002 else if (cortex_a8_reloc
->r_type() == elfcpp::R_ARM_THM_CALL
8004 force_target_thumb
= true;
8008 Stub_type stub_type
= arm_stub_none
;
8010 // Check if we have an offending branch instruction.
8011 uint16_t upper_insn
= (insn
>> 16) & 0xffffU
;
8012 uint16_t lower_insn
= insn
& 0xffffU
;
8013 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
8015 if (cortex_a8_reloc
!= NULL
8016 && cortex_a8_reloc
->reloc_stub() != NULL
)
8017 // We've already made a stub for this instruction, e.g.
8018 // it's a long branch or a Thumb->ARM stub. Assume that
8019 // stub will suffice to work around the A8 erratum (see
8020 // setting of always_after_branch above).
8024 offset
= RelocFuncs::thumb32_cond_branch_offset(upper_insn
,
8026 stub_type
= arm_stub_a8_veneer_b_cond
;
8028 else if (is_b
|| is_bl
|| is_blx
)
8030 offset
= RelocFuncs::thumb32_branch_offset(upper_insn
,
8036 ? arm_stub_a8_veneer_blx
8038 ? arm_stub_a8_veneer_bl
8039 : arm_stub_a8_veneer_b
));
8042 if (stub_type
!= arm_stub_none
)
8044 Arm_address pc_for_insn
= address
+ i
+ 4;
8046 // The original instruction is a BL, but the target is
8047 // an ARM instruction. If we were not making a stub,
8048 // the BL would have been converted to a BLX. Use the
8049 // BLX stub instead in that case.
8050 if (this->may_use_blx() && force_target_arm
8051 && stub_type
== arm_stub_a8_veneer_bl
)
8053 stub_type
= arm_stub_a8_veneer_blx
;
8057 // Conversely, if the original instruction was
8058 // BLX but the target is Thumb mode, use the BL stub.
8059 else if (force_target_thumb
8060 && stub_type
== arm_stub_a8_veneer_blx
)
8062 stub_type
= arm_stub_a8_veneer_bl
;
8070 // If we found a relocation, use the proper destination,
8071 // not the offset in the (unrelocated) instruction.
8072 // Note this is always done if we switched the stub type above.
8073 if (cortex_a8_reloc
!= NULL
)
8074 offset
= (off_t
) (cortex_a8_reloc
->destination() - pc_for_insn
);
8076 Arm_address target
= (pc_for_insn
+ offset
) | (is_blx
? 0 : 1);
8078 // Add a new stub if destination address in in the same page.
8079 if (((address
+ i
) & ~0xfffU
) == (target
& ~0xfffU
))
8081 Cortex_a8_stub
* stub
=
8082 this->stub_factory_
.make_cortex_a8_stub(stub_type
,
8086 Stub_table
<big_endian
>* stub_table
=
8087 arm_relobj
->stub_table(shndx
);
8088 gold_assert(stub_table
!= NULL
);
8089 stub_table
->add_cortex_a8_stub(address
+ i
, stub
);
8094 i
+= insn_32bit
? 4 : 2;
8095 last_was_32bit
= insn_32bit
;
8096 last_was_branch
= is_32bit_branch
;
8100 // Apply the Cortex-A8 workaround.
8102 template<bool big_endian
>
8104 Target_arm
<big_endian
>::apply_cortex_a8_workaround(
8105 const Cortex_a8_stub
* stub
,
8106 Arm_address stub_address
,
8107 unsigned char* insn_view
,
8108 Arm_address insn_address
)
8110 typedef typename
elfcpp::Swap
<16, big_endian
>::Valtype Valtype
;
8111 Valtype
* wv
= reinterpret_cast<Valtype
*>(insn_view
);
8112 Valtype upper_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
);
8113 Valtype lower_insn
= elfcpp::Swap
<16, big_endian
>::readval(wv
+ 1);
8114 off_t branch_offset
= stub_address
- (insn_address
+ 4);
8116 typedef struct Arm_relocate_functions
<big_endian
> RelocFuncs
;
8117 switch (stub
->stub_template()->type())
8119 case arm_stub_a8_veneer_b_cond
:
8120 gold_assert(!utils::has_overflow
<21>(branch_offset
));
8121 upper_insn
= RelocFuncs::thumb32_cond_branch_upper(upper_insn
,
8123 lower_insn
= RelocFuncs::thumb32_cond_branch_lower(lower_insn
,
8127 case arm_stub_a8_veneer_b
:
8128 case arm_stub_a8_veneer_bl
:
8129 case arm_stub_a8_veneer_blx
:
8130 if ((lower_insn
& 0x5000U
) == 0x4000U
)
8131 // For a BLX instruction, make sure that the relocation is
8132 // rounded up to a word boundary. This follows the semantics of
8133 // the instruction which specifies that bit 1 of the target
8134 // address will come from bit 1 of the base address.
8135 branch_offset
= (branch_offset
+ 2) & ~3;
8137 // Put BRANCH_OFFSET back into the insn.
8138 gold_assert(!utils::has_overflow
<25>(branch_offset
));
8139 upper_insn
= RelocFuncs::thumb32_branch_upper(upper_insn
, branch_offset
);
8140 lower_insn
= RelocFuncs::thumb32_branch_lower(lower_insn
, branch_offset
);
8147 // Put the relocated value back in the object file:
8148 elfcpp::Swap
<16, big_endian
>::writeval(wv
, upper_insn
);
8149 elfcpp::Swap
<16, big_endian
>::writeval(wv
+ 1, lower_insn
);
8152 template<bool big_endian
>
8153 class Target_selector_arm
: public Target_selector
8156 Target_selector_arm()
8157 : Target_selector(elfcpp::EM_ARM
, 32, big_endian
,
8158 (big_endian
? "elf32-bigarm" : "elf32-littlearm"))
8162 do_instantiate_target()
8163 { return new Target_arm
<big_endian
>(); }
8166 Target_selector_arm
<false> target_selector_arm
;
8167 Target_selector_arm
<true> target_selector_armbe
;
8169 } // End anonymous namespace.